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ROYAL  IRISH  ACADEMY. 


VOLUME  II.— SCIENCE. 
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DUBLIN: 

PUBLISHED  BY  THE  ACADEMY, 
AT  THE  ACADEMY  HOUSE,  19,  DAWSON-STREET. 

SOLD  ALSO  BT 

HODGES,  FOSTER,  &  FIGGIS,  GRAFTON-ST. 

And  bv  WILLIAMS  &  NORGATE, 
London  :  I  Edinbuooh  : 

Henrietta-street,  Coyent  Garden.      I  20,  South  Frederick-street. 

1875-77. 


LSoc  1802.30 


DUHLIN  : 

yrittUt  st  fit  Kmbtnita  $rMf  ^ 

BY  PONSONBV  AND  MURrHY. 


Thb  AcADEHT  desire  it  to  be  understoodj  that  they  are  not 
atmoerablefor  any  opinion^  representation  offaete^  or  train  of 
reasoning  that  may  appear  in  the  following  Papers,  The 
Authors  of  the  several  Essays  are  alone  responsible  for  their 
contents.       f4c\     j4c{      \^ic\  ^ 


LIST  OF  THE  CONTRIBUTORS, 

WITH  REFERENCES  TO  THE  SEVERAL  ARTICLES  CONTRIBUTED 

BY  EACH. 


Adams,  A.  Lkith,  M.D.,  F.R.S.  page. 

On  a  Fossil  Saurian  Vertebra  {Arcto$aurus  OBhomi)^  from  the 

Arotio  Regions  (with  Illustrations), 177 

Archxr,  William,  F.R.8. 

On    Apotheoia     oocnrring    in    some     Soytonematous     and 

Sirosiphonaoeous  Alg»  (Plate  vi.}, 85 

On  Chlamydomyxa  labyrinthuUndeSy  nov.  gen.  et  sp.,  a  New 

Freshwater  Saroodic  Organism  (Plates  xiy.  and  xy.),  140 

Bailt,  W.  H.,  F.G.S. 

On  Fossils  from  the  Upper  Old  Red  Sandstone  of  Eiltorcan 

Hill,  in  the  Connty  of  Kilkenny  (Report  No.  I.),  45 

Bakjcb,  A&thitr  Wtndows  Willebt,  B.A. 

On  the  ligamentum  Mucosum  (with  Illustrations},  193 

Bakxk,  J.  0.,  F.L.S. 

List  of  Seychelles  MjrtacesB,  with  Descriptions  of  two  New 

Spedes  (Plates  zvi.  and  xvii.), 160 

Ball,  Robert  8.,  LL.D.,  F.R.S. 

On  anElementaiT  Proof  of  '^  Lagrange*  s  Equations  of  Motion 

in  Oeneralizea  Co-ordinates/^ 463 

Bradt,  Hrnrt  B.,  F.R.S. 

On  some  Foraminifera  from  the  Loo  Choo  Islands,  .  .      589 

Burton,  C.  E.,  B.A.,  Member  of  the  Rodriguez  Transit  of  Venus 
Expedition  (British). 

On  a  Spectroscope  of  the  Binocular  Form,  for  the  Observation 

of  Faint  Spectra  (with  Illustrations),         .        »        .  42 

Note  on  the  Spectrum,  Polarization,  and  Form  of  the  Zodiacal 

Light,  as  observed  in  the  years  1874  and  1875  (Plate  xxv.).       218 


vi  List  of  the  Contributors. 

Caset,  J.,  LL.D.,  F.R.S.  page. 

On  the  Equation  of  the  Squares  of  the  Differences  of  a 
Biquadratic, 40 

DaYT,  EDXtTKD,  A.Mo  M.D. 

On  some  newly-observed  Properties  possessed  by  certain  Salts 

of  Fulminic  Acid, 183 

On  a  Ready  Means  of  Detecting  Arsenical  Compounds,    .  225 

On  a  New  Chemical  Test  for  Alcohol, 579 

DOVOTAK,  M. 

On  some  Further  Improvements  of  the  Comparable  Self- 
Kegistering  Hygrometer 166 

Dbisteb,  Johk  L.  £.,  M.A. 

On  Personal  Errors  in  Astronomical  Transit  Observations,  484 

Habdican,  Edwabd  T.,  F.C.S. 

On  two  New  Deposits  of  Human  and  other  Bones,  discovered 
in  the  Cave  of  Dunmore,  Co.  Kilkenny  (Plate  xviii.),  168 

Analysis  of  Coals  and  Iron-stones  from  the  Dungannon  Coal- 
Field,  Co.  Tyrone,  Ireland, 529 

A  Contribution  to  the  History  of  Dolomite  (with  Plates  zli. 
and  xlii.), 705 

Haughtok,  Rev.  Sakxtbl,  M.D.,  F.R.S. — (tSlee  Pluneext,  T.) 

Jellbtt,  Rev.  J.  H.,  B.D.,  S.F.T.C.D. 

.On  the  Chemical  Changes  which  take  place  in  the  Potato 
during  the  progress  of  the  Disease, 736 

Eellt,  J.  E. 

On  a  Case  of  Polydactylism  (Plates  xxzvi.,  xxzvii.,  xxxviii., 
and  xxxix.), 539 

KnfAHAV,  G.  H. 

On  Microscopical  Structure  of  Rooks.  Report  No.  I. — 
Ingenite  Rocks  TPlates  vii.  and  viii.), 94 

On  &anite  and  ouier  Ingenite  Rocks  of  Yar-Connaught  and 
the  Lower  Owle  (Plates  ix.,  x.,  xi.,  xii.),     ....       102 

Report  on  the  Microscopical  Structure  of  Rooks.  No.  II. 
(Plate  viii.  J, 161 

Report  on  the  Microscopical  Structure  of  Rocks.  Report 
No.  III., 164 

On  Ingenite  Rocks.    Report  ^0.  IV., 180 

The  Drifting  Power  of  Tidal  Currents  versus  that  of  Wind- 
waves  (with  Illustrations), 443 

Leeper,  G.  L. 

On  Retro-peritoneal  Cavities  (Plate  v.), 79 

Macalister,  Alexander,  M.D. — {See  also  Plunkett,  T.) 

On  some  Points  in  Bird  Myology  (with  Illustrations),      .        .        56 
On  the  Presence  of  Lachrymo-jugal  Suture  in  a  Human  Skull, 
and  its  Comparative  Anatomy  (Plate  i.),      .        .        .  58 


List  of  the  Contributors,  vii 

IfACALlflTEB,  Alsxaitdsb,  M.D.  (continued),  page. 

On  Two  New  Species  of  Pentastoma  (Plates  ii.  and  iii.))  62 

On  a  Few  Points  in  the  Cranial  Osteology  of  Sloths  (Plate  xiii.)i  139 
On  some  Fonns  of  Ugamentum  Pterygo-spinosum  (Platbs  xix. 

andzx.),    .        .        .' 202 

On  Two  Dissimilar  Forms  of  Perityphlic  Ponohes  (Plate  xziy. ),  214 

Notes  on  some  Anomalies  in  the  course  of  Nerves  in  Man,  426 

MAcnnrosH,  H.  W.,  B.A. 

Notes  on  the  Mvolagy  of  the  Coati-mondis  {N^awa  narica  and 

N./wca)  and  Common  Martin  (Maries ^oina\  ...  48 
On  the  Mnsctdar  Anatomy  of  Chotcepue  duiactylus  (Plate  iv.),  66 
On  a  Malformed  Corona  of  EcMnue  eeculentua  (Plates  xxi.  and 

xxii.), 206 

MooBE,  Dattd,  Ph.  D.,  F.L.8. 

Report  on  Irish  HepaticsB  (Plates  zliii.,  zliv.,  and  xly.),  591 

More,  A.  G.,  F.L.S. 

Report  on  the  Flora  of  Inish-Bofin,  Oalway,  ....      553 

Mow,  RiCHABS  J.,  F.C.S. 

Rej^rt  on  the  Exploration  of  Ballybetagh  Bog  (with  Illnstra- 
tions), 547 

M'Alpine,  Abchibaxd  Nichol. 

The  Detection  and  Precipitation  of  Phosphoric  Acid  by 
Ammonic  Molybdate, 742 

M*Nab,  W.  R.,  M.D.,  Edinburgh. 

Remarks  on  the  Structure  of  the  Leaves  of  certain  Conif  eree 

(Plate  xxiii.),     .        .        .        •. 209 

A  Revision  of  the  Species  of  Abies  (Plates  xlvi.,  xlvii., 
xlviii.,  and  xlix.}, 673 

O'Mrilra,  Rev.  Euoens,  M.A. 

Report  on  the  Irish  Diatomacese.  Part  I.  (Plates  xxvi.  to 
xxxiv.), 235 

Plttxkett,  T. 

On  the  Exploration  of  the  Enockninny  Cave.  .With  an 
Account  of  the  Animal  Remains,  by  Rev.  Professor 
Haitohtok,  M.D.,  F.R.S.,  and  Professor  Macalisteb,  M.D. 
(with  Illustrations), 465 

Plukkett,  William,  ¥.C.Q.—{See  Studdert,  Lancelot,  LL.D,) 

Ports,  George. 

Remarks  on  the  Recent  Discovery  of  Remains  of  the  Cervtu 

Megaceros  at  Ballybetagh, 738 

Retvolds,  J.  Eherson,  M.D. 

On  Glucinum  :  its  Atomic  Weight  and  Specific  Heat,  .       731 


viii  List  of  the  Contributors, 

Robinson,  Rev.  T.  R.,  D.D.,  F.R.S.  paob. 

On  the  TheoiT  of  the  Cup  Anemometer,  and  the  Determina- 
tion of  its  Constants, 427 

SiesBSON,  George,  M.D.,  F.L.8. 

On  Heat  as  a  Factor  in  Vital  Action  (so  called),      ...  1 

On  Changes  in  the  Physical  Oeography  of  Ireland,                  .  6 
On  a  Cause  of  the  Buoyancy  of  Bodies  of  a  gpreater  Density 

than  Water,                               22 

Studdebt,    Lakgblot,  LL.D.,    £x-Soh.,    T.C.D.,   and  Plunkett, 
William,  F.C.8. 
On  the  Constituents  of  the  two  principal  Mineral  Waters  of 
Lisdoonvama,  County  of  Clare, 189 

Studdest,  Lancelot,  LL.D.,  £z-Sch.,  T.C.D. 

An  Estimation  of  the  Free  and  Albuminoid  Ammonia  yielded 
by  the  Stagnant  Waters  of  the  Dublin  Streets,  as  compared 
with  the  quantities  of  those  Substances  obtained  from  the 
Liffey  Water,  after  teceiving  the  Sewage,  459 

TiCHBOBNB,  C.  R.  C,  Ph.  D. 

Laboratory  Notes, 83 

On  Further  Researches  of  the  Dissociation   of  Molecules  in 

Solution, 230 

Wbioht,  Edwabd  Perceval,  M.D.,  F.L.S. 

On  a  New  Genus  and  Species  belonging  to   the   Family 

Pandanna  (Plate  xxxy.}, 683 

Notes   on  a  small   Collection   of    Foraminifera    from    the 

Seychelles, 686 

Description  of    a    New  Ghenus    and   Species    of    Spongo— 

KalUepongia  Archeri  (Plate  xl.}, 764 

YoTJNO,  J.  R.,  M.A. 

On  some  General  FormulsB  for  the  Solution  of  Algebraical 
Equationsof  the  Third  Degree,  &c.,  ....        26 

On  a  certain  relation  between  the  Quadratic  Esroression 
Q*  -  ZPP*  and  the  Product  of  the  Squares  of  the  Dinerences 
of  the  Roots  of  a  Cubic  Equation, 744 


I 

I 


PROCEEDINGS 

OP 

THE  ROYAL  IRISH  ACADEMY. 


SCIENCE, 


PAFEES  BEAD  BEFOBE  THE  ACADEMY. 


L — Oh  Hkai  as  ▲  Factor  tr  Vital  Actiok  (so  called).    By  Oiosai 
SiQEBsow,  M.  D.,  Ch.  M.,  F.  L.  S.  ^ 

[Read  June  24,  1S72]. 

VARIOUS  opiniooshave  been  expressed  concerning  the  nature  of  life. 
Some  regard  it  as  a  peculiar  agency,  essential  to  the  development 
of  organized  creatures,  giving  to  them  the  first  impulse  and  guiding  their 
development,  until  the  close.  With  them  it  is  an  entity,  incompar- 
able with  any  forces  manifested  in  physics,  and  inscrutable  from  a 
physicist  stand-point.  Others  are  content  to  use  the  word  to  cover  the 
total  phenomena  displayed  by  an  organized  Being,  from  end  to  end  of 
its  career;  while  a  third  party  employ  it  to  designate  a  mode  of  activity, 
peculiar  to  such  beiugs,  and  distinguishing  them  from  inanimate  bodies. 

Such  views,  however  hypothetical,  influence  those  who  entertain 
them,  to  no  small  extent,  and,  perhaps,  occasionally  make  those 
partizans  who  would  otherwise  be  inquirers.  Although  theories  may 
sometimes  be  of  much  advantage,  it  can  do  little  harm  when  we  find 
them  clashing  to  put  them  aside,  and  leave  the  question  in  dispute  an 
open  question,  whilst  we  give  freedom  to  a  search  after  facts,  waiting 
for  their  aid  to  form  an  opinion.  The  process  is  less  attractive,  and 
much  slower,  but  it  may  possess  the  qufdities  of  greater  solidity  and 
permanence. 

For  these  reasons,  I  have  ventured  to  invite  attention  to  a  portion 
only  of  the  many  phenomena  whereof  Life  is  made  up — though  this 
portion,  it  is  true,  has  been  held  to  be  highly  characteristic  and  remark- 

B.  L  A.  PSOC. — VOL.  U.,  8IA.  n.,  8CIBNCX.  B 


2  Proceedings  of  the  Royal  Irish  Academy, 

ably  distinguishing, — I  refer  to  certain  of  those  moyemente  which  have 
been  termed  vital  movements. 

"  One  characteristic  of  every  kind  of  living  matter,"  Dr.  Beale 
observes  (Protoplasm,  pp.  402),  "is  spontaneous  movement."  It 
requires  to  be  noted  that  there  the  term  '*  spontaneous  "  implies  a  fore- 
gone conclusion.  In  order  that  the  question  should  be  an  open  one, 
it  is  necessary  to  amend  this,  and  say — "  One  characteristic  of  every 
kind  of  living  matter  is  movement,  the  causes  of  which  are  unknown^ 
and  which  therefore  has  been  called  '  spontaneous  movement.'  " 

*'  This,"  he  adds,  "unlike  the  movement  of  any  kind  of  non-living 
matter  yet  discovered,  occurs  in  all  directions,  and  seems  to  depend 
upon  changes  in  the  matter  itself,  rather  than  upon  impulses  communi- 
cated to  the  particles  from  without." 

Now,  from  facts  which  have  been  under  my  observation  during  the 
space  of  two  years,  I  have  been  brought  to  believe  that  similar  move- 
ments take  place  in  matter  which  would  be  called  non-living,  and  that 
they,  occurring  in  all  directions,  are  due  to  a  transformation  of  heat 
into  a  propulsive  force. 

Dr.  Beale  describes  the  alterations  in  form  to  which  he  has  thus 
alluded  as  characteristic  of  vital  matter :  and  as  they  to  a  considerable 
extent  simulate  those  alterations  in  non-vital  matter,  it  is  desirable  to 
give  his  words: — "The  alteration  in  form,"  he  remarks,  speaking  of  some 
minute  amoebae — fhe  most  minute  he  could  discover — "  was  very  rapid, 
and  the  different  tints  in  the  different  parts  of  the  moving  mass,  result- 
ing from  alterations  in  thickness,  were  most  distinctly  observed.  The 
living  bodies  might,  in  part,  be  described  as  consisting  of  minute 
portions  of  very  transparent  material,  exhibiting  the  most  active  move- 
ments in  various  directions  in  every  part,"  .  .  .  "and,"  he  adds,  "ca- 
pable of  absorbing  nutrient  materials  from  the  surrounding  medium." 
That  we  must  eliminate,  as  not  being  simply  the  manifestation  of  so- 
called  vital  motion.  He  proceeds:  "A  portion  which  was  at  one 
moment  at  the  lowest  point  of  the  mass  would  pass  in  an  instant  to  the 
highest  part  In  these  movements  one  part  seemed,  as  it  were,  to  pass 
.  through  other  parts,  while  the  whole  mass  moved  now  in  one,  now  in 
another  direction,  and  movements  in  different  parts  of  the  mass  occurred 
in  directions  different  from  that  in  which  tiie  whole  was  moving." 
"What  movements  in  lifeless  matter,"  he  asks,  "can  be  compared 
with  them  ?  The  movements  above  described,"  he  adds,  "  continue  as 
long  as  the  external  conditions  remain  favourable ;  but  if  these  alter, 
and  the  amosbe  be  exposed  to  the  influences  of  unfavourable  circum- 
stances— as  altered  pabulum,  cold,  &c. — the  movements  become  very 
slow,  and  then  cease  altogether." 

Now,  my  attention  was  called  to  movements,  very  like  these,  which 
take  place  in  non- vital  matter  by  certain  phenomena  which  I  observed 
to  occur  under  the  microscope,  in  the  minute  globules  of  pyrogenic  oil, 
which  float  about  in  the  tobacco  smoke.  These  globules,  as  I  stated, 
at  the  time  seemed  twirling  about  like  so  many  monads — but  more 
than  this,  they  seemed  to  alter  their  form.     Conscious  that  rapid 


SioifiRSON — On  Seat  as  a  Factor  in  Vital  Action,  3  - 

changes  of  plane  might  account  for  some  of  this,  and  might  be  a  source 
of  error,  I  pushed  my  inquiries  further — though  here,  I  may  observe, 
that  if  such  change  of  plane  were  remarked  when  taking  place  in  living 
matter,  they  would  run  a  risk  of  being  called  vital  movement. 

To  represent  the  cousistency  of  the  amoebaB  a  somewhat  viscid  body 
is  requisite,  say  an  oles^inous  fluid.  By  bringing  drops  of  this  into 
contact  with  a  heated  fluid,  at  various  temperatures,  I  found  that — 
1st,  when  the  subjacent  fluid  was  cold  no  motion  took  place;  2nd, 
when  it  was  very  hot,  no  movement  occurred. 

3rd.  There  is  a  stage,  diifering  for  different  substance,  at  which 
rapid  movement  is  given  to  the  globule.  At  this  stage,  certain  alter- 
ations in  the  colour  of  parts  seem  to  mark  a  change  in  density,  then 
various  alterations  of  form  occur.  Thus  the  globule  may  alter  into  a 
ling,  this  globule  divide  at  one  portion  or  at  several  portions  of  its  cir- 
cumference, and  re-form  rapidly  into  globules,  and  these  changes  may 
proceed  for  some  moments ;  then  they  will  cease.  That  this  stoppage 
is  due  to  some  acquired  tolerance  of  the  heat,  is  shown  by  the  fact 
that  a  new  drop  will  undergo  similar  changes  at  this  temperature. 

If  the  temperature  be  lower,  the  motions  will  be  slower.  Some- 
times no  eversion  may  take  place ;  then  we  may  note  simply  various 
protrusions  from  different  parts  of  the  periphery,  and  the  globule  may 
change  its  rounded  to  an  angular  form.  To  accomplish  these  changes, 
there  must  of  course  be  transference  of  particles,  and  some  of  these  may 
at  times  be  noticed  passing  their  neighbours. 

There  is  sometimes  a  movement  of  the  globules  from  one  part  of 
the  surface  of  the  fluid  to  another ;  thus  the  flrst  contact  of  the  heated 
fluid  occasionally  scatters  its  component  parts  in  all  directions. 

In  such  cases  as  these,  it  is  manifest  that  the  alterations,  transfor- 
mations, and  changes  of  locality  as  well  as  of  shape,  are  due  to  the  con- 
yersion  of  heat  into  a  motor- force  acting  through  the  physical  basis  of 
the  viscid  globule.  The  acquired  tolerance  of  external  influences  is  not 
unknown  in  vital  matter. 

The  description  which  Dr.  Beale  gives  of  the  movements  in  a 
mucus  corpuscle,  applies  to  the  non-vital  movements,  to  a  considerable 
extent.  "No  language  could  convey,"  he  remarks,  *' a  correct  idea  of 
the  changes  which  may  be  seen  to  take  place  in  the  form  of  the 
living  mucus  or  blood  corpuscle :  every  part  of  the  substance  of  a  corpuscle 
exhibits  distinct  alterations  within  a  few  seconds.  The  material 
which  was  in  one  part  may  move  to  another  part.  Not  only  does  tho 
position  of  component  particles  alter  with  respect  to  one  another,  but  it 
never  remains  the  same :  there  is  no  alternation  of  movements.  Were 
it  possible  to  take  hundreds  of  photographs,  at  the  briefest  intervals,  no 
two  would  be  exactly  alike,  nor  would  they  exhibit  different  gradations 
of  the  same  change;  nor  is  it  possible  to  represent  the  movements  with 
any  degree  of  accuracy,  because  the  outline  is  changing  in  many  parts 
at  the  safhe  moment.  I  have  seen  an  entire  corpuscle  move  onwards 
in  one  definite  direction  for  a  distance  equal  to  its  own  length  or 
more.    Protrusions  would  occur  principally  at  one  end,  and  the  general 


4  Proceedings  of  the  Royal  Irish  Academy. 

mass  would  follow.  .  .  .  From  time  to  time  some  of  the  pear-shaped 
protrusions  are  disturbed  from  the  parent  mass,  and  become  independent 
masses  of  germinal  matter,  which  grow  until  they  become  ordinary  pus 
corpuscles.  Are  these  phenomena,  I  would  ask,  at  all  like  any  known 
to  occur  in  lifeless  material  T* 

If  we  abstract  the  questions  implied  in  the  words  ''germinal,"  and 
"  growth/'  I  think  our  answer  may  be  in  the  affirmative. 

We  can  follow  him  into  his  examination  further.  *'  A  bulging  may 
occur"  in  lifeless  as  well  as  in  living  matter  ^'  at  one  point  of  the  cir- 
cumference, or  at  ten  or  twenty  different  points  at  the  same  moment." 
But  he  cannot  prove  that  ''the  moving  power  evidently  resides  in 
every  particle  of  a  very  transparent,  invariably  colourless,  and  struc- 
tureless material.*'  It  seems  to  do  so ;  but  it  would  also  seem  to 
reside  in  every  particle  of  the  lifeless  matter,  when  changing,  if  wo 
were  not  well  aware  that  the  change  is  due  to  a  difference  of  tempera* 
ture. 

It  appears  to  me  that  various  kinds  of  organized  matter  have  what 
I  might  term  specific  temperatures,  the  limits  of  which  vary  in  different 
substances — below  the  lowest  as  above  the  highest  they  are  motionless. 
This  holds  good  of  lifeless  as  well  as  of  living  matter. 

The  objections  which  Dr.  Beale  raises,  justly  enough,  to  certain 
theories  do  not  here  apply.  He  says,  "  because  molecules  have  been 
seen  in  some  of  the  masses  of  moving  matter,  the  motion  has  been  attri- 
buted to  them.  It  is  true,  the  molecules  do  move,  but  the  living 
transparent  material  in  which  they  are  situated  moves  first,  and  the 
molecules  flow  into  the  extended  portion." 

This  may  be  likewise  noticed  in  a  fluid  in  which  are  granules,  when 
it  protrudes  under  the  influence  of  heat.  The  fluid  is  acted  on ;  the 
granules  are  drawn  With  it. 

"The  movements,"  he  adds,  "cannot  therefore  be  ordinary  mole- 
cular movements.  It  has  been  said  that  the  movements  may  result 
from  diffusion,  but  what  diffusion  or  any  other  movement  with  which 
we  are  acquainted  at  all  resembles  them?  Observers  have  ascribed 
them  to  a  difference  of  density  of  different  parts,  but  wlio  has  been  able 
to  produce  such  movements  by  preparing  fluids  of  different  density  ? 
"Not  is  it  any  explanation  of  the  movements  to  attribute  them  to  inherent 
contractility,  unless  we  can  show  in  what  this  contractility  essentially 
consists.  Some  dismiss  the  matter  by  saying  that  the  movements 
depend  upon  the  property  of  contractility,  but  the  movements  of 
biological  matter  are  totally  distinct  from  contractility,  as  manifested 
by  muscular  tissue. 

fie  adds:  "  I  have  often  tried  to  persuade  the  physicist,  who  has  so 
long  prophesied  the  existence  of  molecular  machinery  in  living  beings, 
to  seek  first  in  the  colourless,  structureless,  living  matter.  But  he 
contents  himself  with  asserting  that  such  machinery  exists,  altiiough  he 
cannot  see  it  or  make  it  evident  to  himself  or  others." 

The  instinct  of  the  physicist,  even  if  it  were  no  more  than  an  in- 
stinct, was,  I  think,  right  in  this  matter. 


SiGEBSON — On  Heat  as  a  Factor  in  Vital  Action.  5 

For:— 

First.  By  the  action  of  heat  we  can  produce  various  alterations  in  form 
of  lifeless  matter,  similar  to  those  which  are  seen  occurring  in  living 
matter  in  the  cases  quoted. 

Second.  In  order  that  such  changes  should  occur  in  living  matter, 
heat  is  absolutely  necessary.  Cold  delays  and  stops  them,  as  in  the 
case  of  the  lifeless  matter.  A  certain  quantity  of  heat  is  needed.  Too 
much  as  well  as  too  little  heat  causes  cessation  of  movement;  there  is 
a  maximum  as  there  is  a  minimum  limit. 

We  come  now  to  another  class  of  movements  which  have  likewise 
been  termed  vital.  I  refer  to  circulatory  movements,  such  for  instance 
as  intra-cellular  rotation,  and  cyclosis.  In  a  given  cell,  we  may  occa- 
sionally observe  its  fluid  contents  in  motion,  made  visible  by  a  number 
of  little  granules  that  are  earned  along  with  it.  This  movement  may 
be  simple  rotation,  or  it  may  take  place  in  a  spiral  direction ;  though 
different  courses  may  be  taken  in  adjoining  cells,  the  movement  usually 
keeps  on,  in  one  direction  in  the  same  cell.  Various  ingenious  theories 
have  been  devised  to  account  for  this. 

If,  now,  we  take  a  drop  of  oil  and  approach  it  to  the  flame  of  a  candle, 
it  can  be  seen  that  the  oil,  first  at  rest,  is  set  in  motion,  slow  or  quick 
in  accordance  with  the  less  or  greater  degree  of  heat  exhibited.  A 
little  dust  shaken  into  it  allows  the  rotation  of  the  granule-bearing 
current  to  be  easily  observed  by  those  who  have  a  keen  vision  for  mi- 
nute objects.  A  slender  baton  of  wax  may  be  used :  approaching  the 
flame,  the  point  melts,  a  drop  forms,  and  then  rotation  is  set  up.  If 
instead  of  having  a  rounded  drop,  we  confine  a  fluid  in  a  glass  vessel 
shaped  like  a  long  cell,  the  fluid  inside,  by  approximation  to  the  flame, 
can  be  caused  to  move  longitudinally.  In  a  free  fluid  the  particles  are 
caused  by  heat  to  describe  an  ellipse — they  seem  to  return  in  their 
courses,  and  this  appears  to  be  the  case  where  heat  impinges  on  the 
surface,  so  that  we^  might  expect  to  find  a  kind  of  circulation  or  ro- 
tation set  up  in  water  under  the  influence  of  the  sun,  apparently  similar 
in  kind  to  the  motion  of  the  celestial  bodies. 

To  return  to  rotation  in  cells : — 

First.  Heat  is  capable  of  causing  rotation  in  fluids. 

Second.  The  rotation  observed  in  cells  absolutely  requires  heat.  It 
chilled,  the  motion  is  slackened ;  if  set  under  a  certain  degree  of  cold, 
it  is  stopped  altogether. 

Movement  displaying  different  phenomena  is  that  which  has  been 
termed  cyclosis.  This  is  shown  ih  a  plexus  of  latex-bearing  vessels; 
it  has  been  described  as  analogous  to  the  capillary  circulation  in  animals. 
There  is  no  organ  to  make  a  vis  a  tergo,  and  yet  there  is  movement 
through  vessels  in  which  there  is  no  contraction;  neither  can  it  be 
attributed  to  a  viaafronte.  It  seems  to  take  place  in  all  directions, 
and  has  been  considered  a  peculiar  vital  movement  connected  with 
formative  functions. 

If  now  we  bring  a  heated  body  over  the  surface  of  a  fluid,  we  will 
find  that  currents  will  be  formed  in  all  directions.   In  one  case,  under  a 


6  Proceedings  of  the  Royal  Iriah  Academy, 

heated  point,  I  noticed  an  instance  of  perfect  rotation.  Usually,  how- 
ever, the  currents  are  formed  and  proceed  in  all  directions,  oarrying  with 
them  any  grains  of  dust  that  may  be  in  the  fluid.  The  net- work  of 
laticiferous  vessels,  anastomizing  with  each  other,  lies  under  the  in- 
fluence of  the  sunlight,  as  an  exposed  plane. 

First.  Heat  is  capable  of  producing  various  currents,  moving  in 
diverse  directions. 

Second.  Heat  is  absolutely  required  in  order  that  the  movements 
in  the  latex  vessels  shall  be  produced :  under  little  heat  they  delay ; 
more  heat  quickens  them. 


II. — Ojt  Changes  in  the  Physical   Geographt    of   Ibeland.     By 
Geobge  Sigxeson,  M.  D.,  Gh.  M.,  F.  L.  S. 

[Read  June  28,  1873.] 

It  is  impossible  to  read  the  first  pages  of  our  ancient  annals  without 
being  struck  by  the  frequent  mention  of  certain  singular  phenomena, 
the  periods  of  whose  occurrence  are  referred  back  to  the  earliest  com- 
mencement of  our  history.  With  great  sobriety  of  diction,  and  cir- 
cumstantial precision  of  statement,  we  are  told  that  in  certain  years 
there  burst  forth  certain  lakes,  which  are  duly  named,  and  that  in 
other  years  there  were  eruptions  of  other  lakes,  and  also  eruptions  of 
rivers.     The  dates  and  names  are  set  down  for  every  case. 

Now,  at  first  sight,  these  things  seem  so  improbable,  that  the 
reader  is  inclined  to  believe  the  record  to  be  erroneous,  either  fundamen- 
tally in  fact,  or  superficially  in  the  misstatement  of  ordinary  incidents. 
Floods,  it  might  be  argued,  have  been  magnified  into  the  eruption  of 
rivers,  and  the  overflow  or  inundation  of  a  lake  into  the  outbursting 
of  a  new  lake.  There  is  another  view  also  which  is  seemingly 
shrewd  and  very  plausible.  It  is  that  the  first  discovery  of  lakes  and 
rivers  was  marked  down  as  the  period  of  their  first  appearance.  The 
historian  O'Halloran  may  be  allowed  to  state  this  view,  as  he  does  it 
with  much  earnestness.  In  reference  to  the  recorded  eruption  of  some 
lakes  and  rivers,  he  says :  "  It  is  recorded  that  at  this  time  there 
were  found  in  Ireland,  but  three  lakes  and  nine  rivers,  whose  names 
are  particularly  mentioned;  but  from  this  it  appears  probable  that  the 
parts  of  the  country  in  which  these  lakes  and  rivers  appeared  were 
only  what  were  then  known;  and,  that  as  their  successors  began  to 
explore  and  lay  open  other  parts,  the  rivers  and  lakes  then  appearing, 
were  entered  into  the  national  annals  as  they  were  discovered;  but,  as 
no  previoTj[s  mention  could  have  been  made  of  them,  and  that  the  dif- 
ferent periods  at  which  they  were  found  out  were  distinctly  marked, 
succeeding  annalists  have  dated  the  first  bursting  forth  of  each  from  the 
time  of  its  discovery.  Our  writers  are  very  exact  in  the  times  in 
which  these  rivers  and  lakes  appeared ;  it  cuts  a  conspicuous  figure  in 
our  history,  and  proves  the  extreme  accuracy  of  our  early  writers ; 


SiGERSON — On  the  Physical  Geography  of  Ireland.  7 

but  a  very  unjueftififtble  credulity  in  their  Ruccessors,  who  could  sup- 
pose the  first  discovery  of  them  to  be  their  first  rise.  .  .  But  as  it 
appears  to  be  almost  a  certainty,  that  (with  a  very  few  exceptions) 
rivers  and  lakes  are  nearly  coeval  with  the  creation,  the  reader  will, 
I  hope,  excuse  my  taking  no  further  notice  of  this  part  of  our  history.'' 

Now,  I  confess,  that  on  first  giving  attention  to  these  records  iden- 
tical speculations  presented  themselves  as  ingenious  and  satisfactory ; 
they  accounted  for  everything  by  explaining  all  away.  Fortunately, 
the  language  of  the  annals  is  nof  ambiguous,  and  it  is  impossible  not 
to  perceive  that  when  the  word  eruption  is  employed,  something  is 
meant  quite  different  from  inundation,  a  term  also  used.  Again, 
0*fialloran's  hypothesis  falls  before  the  fact  that  those  lakes  and  rivers 
which,  from  their  position  and  size,  were  most  readibly  discoverable, 
are  not  mentioned  first,  some  of  them  not  at  all.  Of  two  neighbouring 
lakes,  the  larger  and  more  accessible  may  l>e  left  unnoticed,  whilst  the 
eruplion  of  the  smaller  is  chronicled.  Finally,  if  his  hypothesis  were 
valid,  it  would  follow  iErom  the  data  given,  that  Ireland  was  first  co- 
lonized in  that  part  which  is  now  the  county  Mayo,  that  the  newcomers 
soon  discovered  Lough  Conn  and  Lough  Mask,  but  never  found  Lough 
Corrib ;  that  they  afterwards  proceeded  to  prospect  a  few  small  lakes 
in  what  is  now  the  county  Monaghan,  without  ever  having  observed 
the  Shannon's  spreading  sea. 

It  may,  perhaps,  be  possible  to  account  for  the  formation  of  a  few 
lakes  by  some  of  the  changes  operated  on  the  face  of  the  country,  by 
the  progress  of  colonization.  Here  there  is  repeated  mention  of  the 
clearing  away  of  forests.  Fire  as  well  as  the  axe  was  doubtless  em- 
ployed in  this  work,  and  the  charred  remnants  may  occasionally  have 
helped  to  block  the  path  of  flowing  waters  and  bar  the  drainage  of 
small  areas.  The  removal  of  a  forest  from  a  given  space  itself  removes 
a  drainage  organ  of  no  inconsiderable  power.  Hales  found  that  a  sun- 
flower with  a  leaf  surface  of  thirty-nine  square  feet  exhaled  twenty- 
two  ounces  of  water  in  the  twenty-four  hours;  Enop,  that  a  plant  of 
maize,  in  three  months  and  a  half,  exhaled  thirty- six  times  its  own 
weight  of  water.  When  we  consider  how  extensive  is  the  leaf-surface 
of  trees,  and  how  great  the  transpiration,  a  forest  might  almost  be  re- 
garded as  an  engine  for  draining  up  a  river  from  the  earth  and  dissi- 
pating  its  waters  through  the  air  in  the  form  of  insensible  vapour. 
Thence,  it  descends  again  in  showers.  The  first  effect  of  felling  forests 
in  Ireland,  under  the  circumstances  of  the  period  alluded  to,  might 
have  been  therefore  the  formation  of  pools,  streams,  and  lakelets — the 
secondary  effects  would  be  shown  in  their  gradual  drying  up,  when 
the  land  was  exposed  to  the  full  rays  of  the  sun. 

But,  although  we  may  possibly  account  for  the  formation  of  some 
water  courses  and  lakes  in  this  way,  we  do  not  account  for  the  emphatic 
employment  of  the  term  eruption,  nor  for  the  successive  pheno- 
mena chronicled.  It  is  to  be  noted  also,  that  the  clearances  are  not 
coincident  in  space,  nor  always  in  time,  with  the  formation  of  lakes 
and  rivers. 


8  Proceedings  of  the  Royal  Iruth  Academy. 

The  emptions  recorded  in  the  annals  may  be  divided  into  two 
groups  (which  might  be  subdivided  into  minor  groups),  between  the 
occurrence  of  which  a  long  lapse  of  six  centuries  and  a  half  is  related 
to  huTe  taken  place.  However  improbable  may  be  the  pre-Christian 
chronology  here,  as  respects  the  events  attributed  to  particular  years, 
it  seems  reasonable  to  suppose  that  a  succession  of  epochs  might  have 
been  noted  accurately.  I  am  inclined  to  credit  this,  in  the  present 
case,  for  the  following  reasons  :  Following  on  a  map  the  chronicled 
eruptions  of  lakes,  I  united  the  latter,  so  far  as  identified,  by  straight 
lines.  To  my  surprise  I  found  these  lines  arranging  themselves  north  and 
southf  in  a  direction  parallel  to  the  lines  of  longitude.  Thus  it  was 
with  respect  to  Lough  Conn  and  Lough  Mask  in  the  west,  to  Loch 
Laighline  in  eastMeath;  and  Loch  Eochtra,  orMucnama,  inMonaghan; 
to  Derryvaragh  and  Ennel,  in  Westmeath ;  and  to  a  few  others.  About 
four  lines,  running  north  and  south,  each  including  two  or  more  lakes 
in  their  course,  appeared  on  the  map. 

From  the  end  of  the  Nemedian  period,  during  all  the  Firbolgic  and 
De  Dananian  days,*  until  the  Milesian  epoch  had  begun,  no  outburst 
of  lake  or  river  is  recorded.  A  long  interval  of  six  centuries  and  a 
half,  therefore  divides  the  first  great  group  of  lake  eruptions  from  the 
second  group,  in  which  the  eruption  of  both  lakes  and  rivers  is 
mentioned.  Now,  it  struck  me  as  curious  that  the  lines  connecting 
the  principal  lakes  enumerated  lay  in  a  different  direction.  Instead 
of  running  north  and  south  they  run  obliquely  from  south-west  to 
north-east*  Thus,  a  line  drawn  from  Glare  to  Belfast  will  fall  more 
or  less  near  eight  lakes,  whose  eruptions  ai*e  recorded.  Anno  Mundi, 
8503 — ^they  are  Lochs  Oraney  (Co.  Clare) ;  Cimbe  (now  Hackett,  Co. 
Galway) ;  Loch  Baah  (Co.  Boscommon) ;  Een  and  Garadice  (Co. 
Leitrim) ;  and  Loch  Laegh,  now  Belfast  Lough.  At  this  period,  cer- 
tain rivers  break  fortli;  and  of  these  the  Brosnac,  the  Socs  (now  Suck), 
and  the  Inny,  flow  towards  this  line  from  west  and  east,  whilst  others 
in  the  north,  such  as  the  Una  in  Tyrone,  and  the  Callan  in  Armagh, 
and  (perhaps),  the  Fregrabail  (now  the  Ravelwater,  in  Antrim), 
appear  related  to  it. 

The  next  oblique  line  runs  almost  parallel  to  this  on  the  north- 
west; it  covers  in  its  course  the  recorded  eruptions  ofLochFoyle, 
Loch  £me,  and  an  irruption  of  the  sea,  forming  what  is  now  Drum- 
cliffe  Bay.  Towards  this  line  tend  the  three  Finns,  whose  eruption  is 
there  recorded,  and  perhaps,  some  other  streams  named  by  the  anna- 
lists, but  not  identified  by  recent  writers.  Here  again,  we  find  some 
isolated  cases ;  and  rivers  are  mentioned  as  having  burst  forth  in  the 
south-west. 

Bearing  in  mind  the  evidences  of  change  of  levels  which  some  of 
our  beaches  present,  and  the  proofs  of  depression  and  elevation  in  the 


^  Lough  Corrib  [Loch  Oirbaen]  was  formed  in  the  Dananian  period,  according  to 
the  Book  of  Leinster. 


RiGERSON — On  the  Physical  Geography  of  Ireland.  9 

Erne  district,  to  which  I  drew  attention  in  a  former  paper,  it  appeared 
to  be  highly  probable,  that  in  these  lines  we  had  indications  of  ineso- 
seismal  areas.  Their  directions  seem  to  point  out  the  directions  of 
seismic  energy,  in  the  most  ancient  days  of  our  history.  It  has  been 
frequently  found,  where  noted  in  latter  times,  to  run  in  the  directions 
of  those  lines.  The  apparent  change  from  a  vertical  to  an  oblique 
direction,  coincidently  with  the  chronicled  change  from  the  first  great 
group  to  the  second  group  of  phenomena,  tends  to  confirm  the  state- 
ments of  our  annals,  as  far  as  they  relate  to  remarkable  natural  events. 
-That  being  so,  it  next  became  requisite  to  see  whether  earthquakes 
had  been  known  to  occur  in  Ireland;  and  necessary  to  ascertain 
whether  such  occurrences  as  those  chronicled  were  such  as  seismical 
force  would  produce,  and  alone  produce. 

First :  Earthquakes  in  Ireland. 

In  1820,  the  shock  of  an  earthquake  was  felt  in  Cork  and  neigh- 
bouring towns. 

In  1534,  the  Anglo-Norman  chronicles,  state  that  an  earthquake 
was  felt  in  Dublin.     The  Four  Masters  make  no  mention  of  it. 

In  1490,  according  to  the  Four  Masters,  '*  There  was  an  eruption 
of  the  earth  (Maidm-talman)  by  which  a  hundred  persons  were  de- 
stroyed, among  them  the  son  of  Manus  Crossagh  0*Hara.  Many  horses 
and  cows  were  also  killed  by  it,  and  much  putrid  fish  were  thrown  up, 
and  a  lake  in  which  fish  is  now  caught,  sprang  up  in  the  place." 

In  1452,  it  is  related,  that  the  Liffey  was  dry  for  over  two  miles. 
The  Four  Masters  say:  "A  very  wonderful  presage  occurred  in  this 
year,  some  time  before  the  death  of  the  Earl  (of  KUdare),  namely  part 
of  the  Liflfey  was  dried  up,  to  the  extent  of  two  miles."  [Although 
this  does  not  prove  the  occurrence  of  an  earthquake,  it  may  indicate 
seismical  action,  as  several  such  phenomena  are  on  record,  all  more  or 
less  closely  coincident  with  the  occurrence  of  earthquakes  near  or  at 
a  distance.] 

In  1266,  mention  is  made  by  Anglo-Norman  writers  in  Ireland  of 
an  earthquake,  which  is  stated  to  have  been  felt  in  all  parts  of  Ireland. 
The  Four  Masters,  however,  do  not  chronicle  it. 

In  1191,  the  river  of  Galway  (according  to  the  Annals  of 
Kilronan)  dried  up,  and  a  hatchet  and  spear  were  found  in  its  bed. 

In  1178,  the  same  river,  the  Four  M&sters  relate,  was  dried  up 
for  the  period  of  a  natural  day ;  all  the  articles  that  had  been  lost  in 
it  from  remotest  times,  as  well  as  its  fish,  were  collected  by  the  in- 
habitants. O'Flaherty,  in  his  account  of  lar-Connaught,  states,  that 
ancient  annals  describe  the  river  as  having  dried  up  from  Friars^  Isle 
(in  the  lake*  whence  it  issues)  to  the  sea,  from  midnight  till  noon.  It 
seems  probable  that  there  must  have  been  an  upheaval  of  the  bed 
ttf  account  for  such  a  phenomena.* 

*  In  aeyerld  ca«es  where  earthquakes  have  b:}en  recorded  in  recent  times,  as  in  Mr. 
Mallet's  catalogue,  the  temporary  drying  up  of  rivers  has  also  been  observed  to  occar ; 
sometimes  the  connexion  may  not  be  considered  qiiita  proven,  as  when,  in  1786,  the 

K.X.  A.  PROa — VOL.  IX.y  SBB.  II.,  SCIBKCR.  C 


1 0  Proceedings  of  the  Royal  Irish  Academy. 

In  the  fifth  centnry,  it  seems  that  a  remarkable  earthquake  took 
place  which  affected  Tara.  It  occurred  (it  is  said)  when  Odran,  St. 
Patrick's  charioteer,  was  assassinated.  ''And  the  cleric  was  angei^/* 
says  the  author  of  the  Senchus  Mor,  "  and  raised  up  his  hands  towards 
his  Lord,  and  remained  in  the  attitude  of  prayer  with  his  hands  crossed, 
and  there  came  a  g;reat  shaking  and  earthquake  at  the  place,  and  dark- 
ness came  upon  the  sun,  and  there  was  an  eclipse ;  and  they  say  that 
the  gate  of  hell  was  then  opened,  and  that  Teamair  was  in  danger  of 
being  overturned,  and  then  it  was  that  Teamair  became  inclined." 

It  thus  appears,  not  only  that  we  have  had  earthquakes  in  this 
country,  but  that  the  farther  we  go  back  in  authentic  history,  the 
more  striking  seem  to  have  been  their  effects.  This  constant  increase 
in  seismical  energy  appears  to  point  to  the  occurrence  of  still  more 
vehement  action  in  preceding  periods — in  those  periods,  for  instance, 
to  which  so  many  eruptions  of  lakes  and  rivers  are  attributed. 

Secondly  :  Are  the  phenomena  recorded  in  our  annals  such  as  would 
have  been  produced  by  seismical  action,  and  by  that  alone?  We  have 
seen  that  no  other  imaginable  cause  was  competent  to  produce  such 
results ;  it  now  remains  to  .prove  that  seismical  energy  can  produce 
them,  and  to  give  cases  showing  it  to  have  wrought  out  analogous 
effects. 

At  the  outset,  it  is  noticeable  that  almost  all  the  lakes  and  rivers 


river  Teviot  dried  up  suddenly,  and  remaiued  dry  for  two  hours,  within  a  short  time  of 
the  occurrence  of  an  earthquake  at  Messina.  Again,  however,  the  same,  river  suddenly 
dried  up  for  four  hours,  nineteen  days  after  a  shock  had  been  felt  in  1 786,  at  Campsic 
and  Strathblaine,  north  of  Glasgow.  In  other  cases,  however,  the  connection  is  un- 
inistakeable.  Thus,  in  1802,  whilst  the  ground  moved  "  like  waves  of  the  sea,**  and 
partial  subsidences  and  upheavals  were  noted,  it  is  related  that  *Hhe  waters  of  the 
Orinoco  rose  80  high  [apparently]  as  to  leave 'a  large  part  of  the  river  dry,"  correctly 
speaking,  the  river  bed  was  upheaved.  In  1820  a  small  river  in  east  Gothland,  Sweden, 
stopped  at  a  certain  spot,  so  that  its  bed  was  crossed  dry-shod.  In  1830,  the  Douro,  in 
Portugal,  suddenly  dried,  between  Roa  and  Aranda,  at  2  o'clock  in  the  morning,  and 
resumed  its  course  at  10  a.  m..  The  river  Alba  de  Tormes  was  interrupted  in  like 
manner.  Gamier,  in  bis  Meteorologie  relates,  that,  in  1833,  after  an  earthquake  ha«l 
been  felt  at  Linkbping  in  Sweden,  on  the  following  night  ihe  river  near  the  bridge  of 
Montala  stopped,  and  was  raised  up  like  a  kind  of  sea.  The  bed  could  be  passed  dry- 
shod,  although  in  general  60,000  tons  of  water  pass  under  the  bridge  per  minute. 

If  it  be  also  remembered  that,  owing  to  earthquake  action,  the  sea  has,  at  times, 
retired  fVom  bays  and  the  coast,  rushing  up  again  to  a  great  height,  it  seems  possible  that 
the  passage  of  the  Israelities  on  dry  ground  through  the  Red  Sea  was  assisted  (physically) 
by  seismical  action.  A  strong  east  wind  is  mentioned  as  having  caused  the  sea  to  go 
back,  and  pillars  of  cloud  and  fire  were  seen.  It  is  to  be  remarked  that  clouds,  flashing 
of  fire,  fire-balls,  fiery  red  vspours,  as  well  as  thunder  and  lightning,  frequently  accom- 
pany earthquakes.  In  1802,  at  Cahors  (in  France),  and  for  forty  leagues  around  it,  a 
loud  explosive  noise  was  heard,  preceded  by  a  flame,  directed  from  west  to  east,  and 
accompanied  by  a  southerly  wind.  At  Beauvais,  simultaneously  with  a  shock,  a  globe  of 
Are  was  observed  moving  from  east  to  west,  which  disappeared  with*  a  loud  explosion. 
At  Albugnol,  in  1804,  the  heavens  were  obscured  by  a  dark  mist,  which  resolved  itself 
into  a  cload,  when  in  ten  minutes  five  terrible  flashes  of  fire  idsued,  and  after  each  flash 
a  shock  took  place. 


SiGBRSON— On  tlie  Physical  Geography  of  Ireland.         1 1 

whose  emptions  are  chronicled,  are  situated,  or  arise  in  limestone  dis- 
tricts. It  is  known  that  the  sfcrata  of  limestone  may,  and  often  do 
include  subterranean  reservoirs  and  channels  of  water ;  an  instance  of 
the  latter  is  found  in  the  case  of  the  underground  river  near  Cong. 
With,  perhaps,  an  exception,  the  lakes  found  in  districts  from  which 
limestone  is  absent,  as  Lough  Foyle,  Belfast  Lough,  are  loughs  which 
comniiinicate  with  the  sea,  and  may  have  received  their  waters  from 
it.  I  now  proceed  to  give  parallel  cases  for  those  mentioned  in  the 
Irish  Annals. 

Eruptions  of  lakes  constitute  the  first  category  of  observed  pheno- 
mena.  The  Irish  Annalists  chronicle  the  eruption  or  bursting  forth 
of  the  following  lakes  \— 

A.  M.  2532.  The  eruption  of  Loch  Conn  and  Loch  Techeat. 
A.  M.  2533.  The  eruption  of  Loch  Mask. 

A.  M.  2535.  Loch  Laighline  sprang  forth.  The  eruption  of  Loch 
Eachtra  also. 

A.  M.  2859.  Loch  Derry varagh  and  Loch  Ennell  sprang  forth,  and 
about  this  period  sprang  forth  Loch  GaU  and  Loch  Ramor. 

A.  M.  3506.  Eruption  of  the  following  lakes :  Cimbe,  Buadaig, 
Baad,  Ben,  Finnmaige,  Greine,  Biach)  Da-Chaech,  and  Loch  Laegh. 

A.M.  3581.  Eruption  of  nine  lakes:  Uair,  larn,  Ce,  Sailean, 
Ailleann,  Feabail,  Oabair,  Bubloch,  and  Loch  Daball. 

A.  M.  3790.  Death  of  the  monarch  Aengus.     These  are  the  lakes 
which  burst  forth  in  his  time :  Aenbeite,  Saileach,  and  Na-ngasan. 
*A.  M.  4694.  Loch  Melvin  burst  forth  over  the  land  in  Cairbre. 
Parallel  eases.  These  have  occurred  usually  but  not  necessarily 
coincidently  with  earthquakes,  though  the  shock  may  not  have  been 
felt. 

The  cases  recorded  are  compiled  from  Mallet's  catalogue  :— 
A-  D.  1790.  Terra  !Nova,  Sicily.     The  gradual  sinking  of  a  piece  of 
ground,  three  Italian  miles  in  circumference,  to  a  depth  of  thirty  feet, 
took  place.     From  fissures  in  the  soil  burst  forth  vapours,  petroleum, 
sulphur,  hot  water,  and  finally  a  stream  of  salt  mud. 

A.  D.  1790.  South  America^  A  piece  of  forest  land,  resting  on 
granite  between  the  villages  of  San  Pedro  de  Alcantara  and  San  Fran- 
cisco de  Aripao  sank  eighty  or  cme-hundred  feet,  and  produced  a  lake 
foor-hundrcMi  toises  in  diameter. 

A.  D.  1792.  The  ground  opened  about  Tureguraqua,  and  lakes 
were  found. 

A.  D.  1802.  South  America.  A  piece  of  ground,  one-hundred  feet 
long  and  forty  feet  wide  sank  down,  and  a  pool  of  water  appeared  in 
its  stead. 

A.  D.  1805.  Earthquake  at  Naples.  At  Bojano  a  lake  made  its 
appearance. 

A.  D.  1806.  Siberia.  A  mountain,  distant  twelve  versts  from 
Erasnojarsk  was  replaced  by  a  lake  of  three  hundred  feet  in  circumfe- 
rence, and  one-hundred  and  eighty  feet  in  depth,  in  some  places ;  the 
water  in  which  had  the  taste  and  smell  of  sulphur. 


12  Proceedinga  of  the  Royal  Irish  Academy. 

A.  D.  1806.  Italy.  At  the  mountain  of  La  Fajola  a  lake  of  sul- 
phurous water  was  formed. 

A.  D.  1810.  San  Miguel,  Azores.  The  village  of  Las  Casas,  con- 
sisting of  twenty- two  houses,  disappeared,  and  a  lake  of  boiling  sulphu- 
rous water  appeared  in  its  place. 

A.D.  1811.  Earthquake  felt  in  the  valley  of  the  Mississippi, 
Ohio,  Arkansas.  During  the  shocks,  great  clefts  appearedin  the  ground, 
from  which  quantities  of  water,  sand,  and  pieces  of  coal  were  thrown 
out.  Large  lakes  were  formed  in  many  places  The  level  of  the 
ground  was  permanently  raised  and  depressed  in  various  localities. 

The  second  category  of  cases  includes  irruptions  of  the  sea.  Of 
these,  the  Irish  Annalists  record  the  following  t — 

A.  M.  2545.  Rury,  son  of  Partalon,  was  drowned  in  Loch  Rury 
[the  estuary  of  the  river  Erne],  the  Loch  having  flowed  over  him ; 
and  from  him  the  Loch  is  named. 

A.  M.  2546.  An  inundation  of  the  sea  [sea-flood]  over  the  land 
at  Brena,  this  year,  and  this  [loch  so  formed]  is  named  Loch  Cuan 
[now  Strangford  Lough]. 

A.  M.  3506.  The  eruption  of  Loch  Da-Chaech,  now  Waterford 
Harbour. 

A.  M.  3581.  The  eruption  of  Lough  Foyle. 

A.  M.  3790.  The  eruption  of  the  sea  between  Eaba  and  Loch  Cetle, 
forming  the  creek  of  Drumcliffe. 

Parallel  cases :  A.  D.  1812.  Marseilles.  The  sea  retired,  leaving 
the  port  dry,  and  rushed  in  again,  inundating  the  quays. 

A.  D.  1817.  Athens.  The  shock  of  an  earUiquake  was  felt, 
accompanied  by  an  inundation  of  the  sea. 

A.  D.  1820.  Acapulco.  The  sea  retired  from  half  the  bay,  and 
returned,  rising  to  a  church  on  the  highest  side  of  the  town. 

A.  D.  1821.  Zante,  Morea.  The  waters  of  the  Alcyonic  sea  (a  part 
of  the  Gulf  of  Corinth),  rose  suddenly,  inundating  the  country  and 
carrying  away  houses. 

,    A.  D.  1822.  ChilL    The  sea  rose  to  an  amazing  height,  fell,  and 
rose  again,  and  thus  continued  for  a  quarter  of  an  hour 

The  third  category  includes  the  sudden  overflowing  of  lakes.  The 
Irish  Annalists  chronicle  but  one,  I  think  of  such  occurrences : 

**  A.  M.  3751.  A  battle  was  fought  against  the  Emai,  a  sept  of  the 
Firbolgs,  where  Loch  Erne  is.  After  the  battle  was  gained  from  them 
the  lake  flowed  over  them.'*  It  would  appear  then  that  this  was  not 
an  eruption  but  the  sudden  overflowing  of  an  already  formed  lake. 

Parallel  cases :  A.  D.  1789.  Iceland.  Lake  Thingvallevate  became 
dry  in  places  where  it  had  formerly  been  twelve  feet  deep,  and  over- 
flowed its  eastern  shore. 

A.  D.  1817.  The  waters  of  the  Lake  of  Geneva  were  momentarily 
raised. 

A.  D.  1820.  Shock  at  Port  Glasgow.  The  waters  of  Loch  Lomond 
were  agitated,  and  rose  somewhat  so  that  persons  crossing  it  were 
alarmed  by  the  sudden  rippling  of  the  waters. 


SioBRSOX — On  the  Physical  Geography  of  Ireland.         13 

A.  D.  1823.  The  waters  of  Lake  Erie  rose  suddenly  to  the  height 
of  nine  feet  on  the  Canadian  shore,  carrying  men  and  boats  inland  with 
irresistible  force.  The  waters  then  fell  but  rose  again  twice  to  a  height 
of  seven  feet.  It  was  reported  that  the  shoek  of  an  earthquake  had 
been  felt. 

In  the  fourth  category  I  haye  placed  the  eruptions  of  streams  and 
rivers.  The  Irish  Annfds  enumerate  several  such  outbursts,  which 
all  are  included  in  the  second  and  later  group. 

A.  M.  3503.  The  eruption  of  the  seven  Brosnas— now  two,  the 
other  seven  being  tributary  streams ;  of  the  nine  Righes,  in  Leinster ; 
and  of  the  three  Mnsionns,  in  Tirerril. 

A.M.  35 1 0.  The  eruption  of  the  Inny,  in  Westmeath ;  of  the  three 
8oc8 ;  the  Suck  and  its  affluents,  in  Connaught ;  and  the  Fregabail, 
now  Havelwater,  Antrim. 

A.M.  3520.  Irial  son  of  Heremon  died.  During  his  reign  took 
place  the  eruptions  of  the  Suir^  the  Feil,  the  Ercere,  in  Munster ;  the 
three  Finns  in  Ulster,  and  the  three  Corindes. 

A.  M.  3656.  The  three  black  rivers  of  Ireland  burst  forth,  the  Una, 
Tyrone;  Forann  and  Callan,  Armagh. 

A.M.  3751.  The  monarch  Fiacha  died.  It  was  in  his  reign  the 
springing  of  these  rivers  :first  took  place,  namely,  the  Fleasg,  the 
Mang,  and  the  Labrann,  in  Kerry. 

A.  M.  41 69.  The  monarch  Sima  died.  In  his  reign  of  a  century 
and  a  half,  took  place  the  eruptions  of  the  rivers,  Skirt,  Doailt,  in 
Monaghan ;  the  Nith  (river  of  Ardee,  Louth) ;  the  Laune,  in  Kerry ; 
and  the  Slaine,  a  tributary  of  the  Boyne. 

Parallel  cases :  A . D.  1 797.  Quito.  The  ground  opened  about  Tun- 
guragua  in  enormous  clefts,  from  which  volumes  of  water  and  stinking 
mud  issued,  forming  lakes  in  many  places,  of  considerable  extent 

A.D.  1802.  The  earth  opened  at  Bucharest,  and  greenish  water 
was  poured  forth,  diffusing  an-odour  of  sulphur  through  the  whole  city. 

A,  D.  1804.  At  Badisen,  Silesia,  springs  suddenly  burst  from  the 
mountain,  and  the  Elbe  and  neighbouring  rivers  inundated  their 
banks. 

A.  D.  1804.  Spain.  Near  Albugnol  the  mountain  was  cleft,  and 
a  stream  was  poured  forth  on  the  lower  part  of  the  town.  Springs 
disappeared  and  new  ones  appeared. 

A.  D.  1809.  Capetown.  In  Blanweberg's  valley  fissures  appeared, 
and  muddy  water  was  thrown  up  to  a  height  of  six  feet  through  holes 
in  the  sandy  soil. 

A.D.  1812.  At  Caraecus,  South  America,  an  immense  torrent  of 
water  burst  forth. 

A.  J).  1828.  Peru.  At  Surras,  streams  of  water  burst  forth  from 
the  earth. 

A.D.  1828.  Caucasus.  Three  large  springs  burst  forth,  fissures 
and  other  springs  appeared. 

A.D.  1829.  Spain.  At  Murcia,  fissures  opened,  and  from  some 
small  holes  sand  was  spirted  out,  from  others  water. 


14  Proceedings  of  the  Royal  Iriah  Academy, 

A.D.  1840.  Ararat  Water  spouted  up  from  holes  in  the  ground; 
new  springs  flowed,  and  old  ones  dried  up. 

Whilst  in  all  the  categories  of  general  phenomena  we  find  parallel 
phenomena — the  results  of  seismicid  action — thus  produced,  there  are 
certain  special  phenomena  which,  though  apparently  incredible,  find 
also  their  analogies  in  the  effect  of  seismic  force.  Take  for  example, 
the  incidents  of  the  eruption  of  the  earth  which  resulted  in  the  for- 
mation of  Meem  Lough,  a.  d.  1490.  Many  men  and  cattle  were 
destroyed,  and  putrid  fish  were  thrown  up.  Destruction,  according  to 
evidence  of  modem  cases,  may  be  worked  by  the  opening  of  chasms 
which  swallow  up  houses  and  men,  by  the  sudden  outburst  of  water, 
or  by  the  expulsion  of  suffocating  vapours,  such  as  burst  forth  from 
the  lake  of  Quilotoa,  South  America,  in  1797,  and  which  proved  fatal 
to  herds  of  cattle  grazing  on  its  shores.  The  death  of  fish  is  a  frequent 
incident,  under  such  circumstances,  in  any  adjacent  or  previous  formed 
pools:  thus  in  1824,  a  lake  near  Lucca  was  observ^  to  be  greatly 
agitated,  a  sulphurous  smell  came  from  it,  and  many  dead  fi^  were 
seen  floating  upon  it.  At  Manilla,  one  of  the  Philippine  Islands,  the 
earth  opened  in  1844,  and  dead  fish  were  observed  immediately  after 
floating  on  a  neighbouring  river.  Similar  occurrences  marked  the 
disappearance  of  Lake  Telchef,  in  Lithuania,  which  I  described  in  a 
previous  paper  (Proc.  B,  Irish  Acad.  Science,  Vol.  I.,  Ser.  n.,  p.  224, 
foot  note). 

Other  special  phenomena  which  I  consider  to  be  explicable,  by 
the  supposition  of  seismical  action — ^the  prevalence  of  which  in  ancient 
times  is  now,  I  hope,  proved — form  an  extremely  curious  and  inter- 
esting group.  They  are  interwoven  with  the  legends,  the  superstitions, 
and  the  poetry  of  the  people. 

Some  legends  refer  to  lakes.  At  times,  it  is  said,  these  sheets  of 
water  appear  troubled  without  apparent  cause ;  whilst  all  is  still, 
ripples  and  waves  break  over  them,  and  vaporous  forms  ascend  from 
the  depth,  whose  embrace  sometimes  carries  the  gazing  mortal  away 
from  this  world  to  the  mysterious  pleasures  of  another.  Now,  when 
we  become  conversant  with  the  phenomena  of  seismical  action,  nothing 
can  seem  more  obvious  than  that  all  these  legends  had  their  foundation 
in  the  fact  that  the  waters  of  lakes  do  become  greatly  agitated  without 
apparent  cause,  and  emit  vapours  of  a  kind  often  suficiently  powerful 
to  relieve  man  from  the  anxieties  of  this  life.  Knowing  of  such 
vapours  and  finding  that  some  who  had  been  subjected  to  their  influ- 
ence lay  dead  when  they  had  passed,  the  poetic  imagination  of  the 
people  figured  that  the  spirits  had  been  stolen  to  fairy  land. 

In  other  cases,  there  is  not  only  strange  commotion  observed,  but 
unwonted  sounds,  as  of  the  bellowing  of  monstrous  animals  and  the 
hissing  of  serpents  are  heard.  In  our  Ossianic  poems,  and  elsewhere, 
these  are  mentioned  and  attributed  to  the  convulsions  and  wri things 
of  the  terrible  Piast,  supposed  to  inhabit  such  lakes.  Heading  those 
romances,  one  is  inclined  to  believe  them  baseless — nevertheless,  they 
have  a  foundation  in  fact.     Thus,  coincidently  with  the  Lisbon  earth- 


SiOERSON — On  the  Physical  Geography  of  Ireland.  15 

quakes  of  1755  and  1827,  an  eztraordmary  noise  was  heard  in  the 
lake  of  Salungen,  in  Saxony;  and  in  1799,  at  Cumanas,  in  South 
America,  the  waters  of  a  lake  hecame  exceedingly  troubled,  and  a 
strange  subterranean  noise  was  heard  proceeding  from  it,  comparable  to 
a  **  prolonged  bellowing,"  and  at  other  times  to  a  hissing  sound.  To  a 
pastoral  people  hearing  such  sounds,  nothing  could  be  more  natural 
than  that  they  should  consider  that  some  animal  infested  the  lake, 
troubled  it  by  its  movements,  and  terrified  them  by  its  roaring. 

Some  legends  refer  to  wells.  It  is  usually  said  that  a  well  was 
laid  under  a  magic  spell  of  some  kind,  which  to  break  insured  destruc- 
tion. In  a  hapless  moment  the  warning  is  forgotten ;  a  damsel  omits 
to  replace  a  cover  or  perform  some  stipulated  act ;  forthwith  the  waters 
arise,  overflow,  inundate  the  valley,  and  overwhelm  perhaps,  a  town. 
This,  for  instance,  is  the  tradition  of  the  origin  of  Lough  Neagh,  and 
Giraldus  Cambrensis  relates  that  the  fishermen  used,  in  clear  weather, 
frequently  to  point  out  to  strangers  the  submerged  ruins.  Moore  has 
commemorated  the  incident  in  verse,  since  which  time  it  has  been  taken 
as  a  purely  poetical  fiction.  Nevertheless,  it  may  have  been  founded 
upon  fact.  Under  seismical  action,  wells  have  frequently  attracted  at- 
tention; sometimes  the  water  fails,  and  they  dry  up,  sometimes  it  arises 
and  overflows:  In  1 809,  in  the  Abruzzi  Ulteriora,  at  Aquita,  some 
springs  appeared  to  boil  up.  In  18d2,  at  Eoligno,  a  man  going  to  draw 
water  at  a  well  found  it  filled  and  overflowing,  then  came  a  shock,  and 
when  he  returned  it  was  empty.  Ancient  dry  wells,  on  the  other 
hand,  have  suddenly  filled  up,  and  the  eruption  and  outbursting  of  new 
springs  and  considerable  torrents  are  not  infrequent  incidents.  At 
the  time  the  occurrence  happened  in  an  Irish  district,  the  overflow 
of  the  well  doubtless  indicated  seismical  action,  and  was  accompanied 
or  followed  by  shocks  and  subsidence  of  the  soil,  such  as  we  have  seen. 
Villages  have  thus  been  occasionally  overwhelmed  with  waters,  but  I 
find  a  curiously  parallel  case  to  Lough  Neagh,  in  Italy.  There,  whilst 
an  earthquake  was  felt  in  north  Italy  and  Switzerland,  the  castle  of 
Manguin,  situated  on  the  shore  of  a  small  lake,  sank  down  and  was 
covered  by  the  water.  There,  also,  the  fishermen  might  have  pointed 
out  to  strangers,  **  the  towers  beneath  them  shining."* 

It  only  remains  to  consider  the  phenomena  which  gave  rise  to  the 
fable  of  the  Land  of  Youth,  Hy-Brasail,  the  Land  of  the  Blest.f    An 


*  The  aadden  subsidence  of  the  foundation,  and  the  vibration  of  shocks  would  scarcely 
fail  to  shatter  buildings  tbna  affected.  But  their  ruins  would  exist.  It  is  certainly 
curious  that  Giraldus  Cambrensis  should  be  able  to  state  that  the  fishermen,  at  that  time, 
frequently  showed  the  submerged  towers  to  woudering  strangers  on  clear  days.  **  Pisca- 
tores  aquas  illius  turras  ecclesiasticas,  quie  more  patri»  arctss  sunt  et  alias,  necnon  et 
rotuedee,  sub  undis  manifeate  sereno  tempore  conspiciunt,  et  extraneis  transeuntibus, 
reique  causas  admirantibus,  frequenter  ostendunt." 

t  "  The  inhabitants  of  Arranroore  are  still  persuaded  that,  on  a  clear  day  they  can  see 
from  this  coast  Hy-Brasail  or  the  Enchanted  Island,  the  Paradise  of  the  Pagan  Irish, 
and  concerning  which  they  relate  a  number  of  romantic  stories."  Beaufort^  Ancient 
Topography  of  Ireland. 

It  Ims  been  stated  thnt  a  similar  "*  Enchanted"  island  was  observed  off  the  coast  of 
Donegal. 


16  Proceedings  of  the  Royal  Irish  Academy 

enchanted  island  has  been  supposed  to  exist  beyond  our  western  shores, 
which  became  visible  on  some  rare  occasions  of  old,  and  to  some  pri- 
Tileged  persons.  Now,  however  beautiful  and  improbable  the  tradition 
may  be,  it  has  become  plain  to  me  that  there  really  was  such  an  island. 
The  legend  may  have  been  perfectly  accurate  aft  to  the  statement  that 
at  one  time  it  was  seen,  and  at  another  it  became  invisible. 

There  are  several  instances  on  record,  even  in  recent  times,  when 
islands  have  been  raised  through  the  disparted  waters  of  the  sea, 
remaining  for  a  time  above  its  surface,  but  finally  disappearing. 
Thus,  in  1707,  after  a  shock,  there  was  seen  from  Santorine  a  floating 
rock,  which  stoutly  arose  above  the  waters,  forming  an  isle.  In  1 803, 
an  island  rose  in  the  Claveezer  See,  in  Holstein ;  it  was  afterwards 
washed  away  by  the  waves.  In  1814,  after  an  earthquake  shock  had 
been  felt,  it  was  noticed  that  a  small  islet  in  the  Greek  Archipelago, 
named  Salomon's  Island  by  the  Turks,  had  suddenly  disappeared.  In 
the  same  year,  a  small  islet  made  its  appearance  in  the  Sea  of  Azov, 
but  was  afterwai*ds  washed  away. 

From  the  Irish  records  it  appears  that  some  formerly  known  islands 
have  disappeared  from  off  our  western  coasts ;  and  from  what  we  may 
infer  from  legendary  lore  it  appears  probable  that  the  story  of  Hy-Bra- 
sail  is  based  upon  subsidence  of  islands  duo  to  earthquake  action.  It 
is  possible  that,  in  ancient  times,  an  archipelago  of  scattered  islands 
may  have  stretched  out  towards  the  American  continent,  and  if  this 
were  so,  it  is  possible  to  conceive  of  such  adventurous  voyages  as  that 
of  St.  Brendan,  without  greatly  straining  the  imagination.  The  ocean 
desert  would  then  have  had  its  oases. 

The  conformation  of  the  bottom  of  the  Atlantic  basin  lends  support 
to  the  supposition,  and  strengthens  the  opinion  that  Ireland  must  have 
lost  ground  to  the  encroaching  waters  of  the  west.  Even  off  the  east 
coast,  it  appears  also  to  have  ceded  portions  of  its  territory.  On  Keith 
Johnson's  Physical  Map  a  tract  is  marked  out,  with  the  observation 
that  ''  this  region  was  probably  land  during  the  period  of  the  Irish 
Elk." 

It  would  be  a  curious  question  to  investigate  how  far  the  ancient 
Irish  legends  of  Hy-Brasail,  and  the  classic  legend  of  Atlantis,  might 
bear  upon  the  former  existence  of  that  supposed  submerged  continent, 
which  now  produces  nothing  but  forests  of  sea- weed. 

Geological  evidence :  The  labour  of  collecting  geological  evidence 
for  each  case  mentioned,  would,  as  may  be  supposed,  be  quite  beyond 
the  limits  of  my  present  purpose  and  opportunities  It  may  suffice, 
however,  to  call  attention  to  certain  acknowledged  facts  which  tend, 
unmistakeably,  to  corroborate  the  statements  made  with  regard  to  the 
action  and  influence  of  seismical  energy,  in  former  times. 

North  and  south,  along  the  coast- line  of  this  country,  the  presence 
of  raised  beaches  gives  proof  of  permanent  upheavals;  evidence  of 
subsidence  may  also  be  found,  whilst  the  character  of  the  strata  in 
certain  districts  confirms  the  view  that  alterations  of  level,  resulting 
in  the  eruption  of  water,  have  taken  place. 


SiGBRSON — On  the  Physical  Geography  of  Ireland.         1 7 

In  the  west,  whilst  local  tradition  relates  that  off  the  west  coast  of 
Achill  there  is  a  beantiful  land  snnk  beneath  the  waves,  with  its  fields 
and  city,  the  physical  appearance  of  Sliav  Cruachan  is)  such  as  to 
suggest  partial  subsidence.  "  There  are  evident  indications  here  of 
Sliav  Cruachan  having  been  sliced  down,"  writes  the  Rev.  Caesar 
Otway,*  "  and  left  as  it  were  the  palpable  remnant  of  some  great  con- 
vulsion ;  for  just  behind  the. precipice  where^it  is  highest,  and  about 
twenty  feet  from  the  brow,  an  anterior  chasm  is  seen,  forming  an 
enormous  and  rugged  fissure  for  hundreds  of  yards  along — in  some 
places  hundreds  of  feet  deep ;  and  this  shows  that  when  the  mighty 
blow  was  given,  and  while  half  the  mountain  was  falling  down,  this 
crack  took  place.  It  was  but  a  chance  that  this  great  slice  did  not  go 
down  along  with  the  rest." 

That  subterranean  waters  exist,  which,  under  the  influence  of 
earthquake  action,  may  be  brought  to  light  is  a  proven  fact.  In  the 
neighbourhood  of  Cong,  the  curious  tourist  may  even  now,  by  descend- 
ing into  a  deep  cavern,  behold  a  subterranean  river — one  of  several 
streams,  which,  percolating  through  the  limestone  strata,  convey  tho 
waters  of  Lough  Mask  to  mingle  with  those  of  Lough  Corrib.  In 
Nimmo's  report  upon  the  geological  structure  of  Connemara,he,  writing 
of  this  district,  says:  '*  The  fletz  limestone,  passing  under  Lough  Corrib, 
occupies  the  greater  part  of  the  provinces  of  Connaught  and  Leinster.'* 
The  boundary  of  this  rock  runs  nearly  in  a  straight  line  to  Oughtc- 
rard,  from  Oughterard  it  turns  to  the  north,  and,  crossing  the  lake, 
appears  on  the  opposite,  a  little  to  the  west  of  Cong,  and  occupies  the) 
southern  margin  of  Lough  Mask.  The  boundary  now  is  lost  in  Lough 
Mask,  but  reappearing  at  the  upper  or  northern  extremity,  turns  off 
towards  Westport;  about  three  miles  short  of  that  town,  however,  it 
turns  north-  east  to  Castlebar.  *  *  It  is  particularly  worthy  of  remark, '  * 
he  adds,  ''  that  along  the  borders  of  the  fietz  limestone  there  are  series 
of  vast  caverns  usually  with  subterranean  rivers  traversing  them. 
Though  this  be  a  common  occurrence  in  the  limestone  countries,  there 
are  few  instances,  I  believe,  so  remarkable  as  in  this  tract.  A  suc- 
cession of  lakes  having  no  visible  outlet  occurs  in  the  same  situation ; 
of  these.  Lough  Mask  is  by  far  the  most  considerable.  The  drainage  of 
a  country  of  two-hundred  and  fifty  square  miles  sinks  here  in  a  basin 
of  forty  square  miles,  and  after  a  subterranean  course  of  two  miles  rises 
in  several  magnificent  fountains  to  join  Lough  Corrib.  On  the  south 
of  Lough  Corrib  also,  the  Koss  Lake  has  no  visible  outlet,  though  it 
receives  the  waters  of  a  large  tract  of  mountain*  The  waters  of  Lough 
Mask  are  visible  on  the  passage  in  several  large  caverns  near  Cong,  but 
those  of  Boss  probably  rise  in  Lough  Corrib,  by  an  inverted  syphon. 
There  are  two  or  three  other  smaller  lakes,  to  the  east  of  Boss,  and 
probably  of  a  similar  description." 

From  their  geological  situation.  Loughs  Corrib,  Mask,  and  Conn 


♦  Tour  In  Connaagbt. 

mi    A.  PEOC— VOL.  II.,  fiEB.  IT.,    SCICNCK. 


18  Proceedings  of  the  Royal  Irish  Academy, 

and  minor  lakes — ^lying  north  and  south — seem  to  have  been  produced 
at  the  same  period,  by  earthquake  action  running  in  a  direction  almost 
due  north  and  south. 

Proceeding  northwards,  the  record  which  relates  to  the  eruption  of 
Lough  Eme  appears,  also,  corroborated  by  certain  physical  facts. 
According  to  the  chronicle,  the  breaking  forth  of  the  water  drowned 
some  of  the  Emai  tribe,  then  upon  its  plain.  The  aspect  of  the  locality 
indicates  ancient  changes  of  level ;  thus,  Dr.  0' Donovan,  when  describ- 
ing it  whilst  on  the  Ordnance  Survey,  wrote :  **I  passed  over  the  great 
cliffs  that  overhang  the  plain  of  Fweealt  of  Toorad.  This  Eweealt 
is  a  level  district  running  about  five  miles  along  the  north-west  bank 
of  the  great  Lough  Erne.  The  name  ( Faoi  alt)  signifies  '  under  the 
height,'  '  subrupian.'  It  is  grand  and  beautiful,  and  seems  to  have 
been  formed  when  the  awful  commotion  took  place  that  formed  Lough 
Eme.  It  was  by  a  depression  of  the  earth,  occasioned  by  some  sub- 
terranean commotion  similar  to  the  one  that  in  later  times  destroyed 
the  city  of  Lisbon."*  Distinct  proof  of  a  former  upheaval  is  found  in 
the  remarkable  discovery,  which  Professor  W.  K.  Sullivan  has  commu- 
nicated, of  a  dolphin's  skull,  which  lay  twenty  feet  beneath  the  surface 
of  a  bay,  at  Pettigo,  near  Lough  Eme.  It  follows  from  this  that  the 
locality  was  once  submerged,  that  the  sea  ran  in  as  far  as  the  site  of 
the  present  town  of  Enniskillen,  and  that  it  was  probably  continuous 
with  the  Foyle,  at  Strabane  and  Derry.  Thus,  at  that  period,  Donegal 
would  have  been  isolated.  Afterwards,  there  was  a  great  and  extensive 
upheaval,  which  raised  this  district  so  much  that  the  surface  of  the 
Lough  is  now  about  one-hundred  and  fifty  feet  above  the  level  of  the 
sea  at  low  water. 

As  there  are  raised  beaches  along  the  northern  coast,  it  appears 
likely  that  they  were  elevated  about  the  same  period,  and  that  the  in- 
fluence of  earthquake  action  extended  over  the  north  of  Ireland.  It 
is  recorded  that  the  late  Mr.  Du  Noyer  discovered  some  flint  weapons 
amongst  the  gravels  of  the  raised  beaches  of  Down  and  Antrim.  If, 
therefore,  we  hold,  as  seems  most  probable,  that  the  various  upheavals 
in  the  province  took  place  about  the  same  period  of  time,  we  may  come 
to  the  curious  conclusion  that  those  who  fashioned  and  used  the  flint 
weapons,  so  discovered,  may  have  been  the  contemporaries  of  the 
Emai. 

That  there  should  be  raised  beaches  at  or  near  Lough  Foyle  is 
what  we  would  anticipate  from  its  seismical  connexion  (so  to  speak) 
with  Lough  Eme.  Nor  are  they  wanting.  Instances  of  elevation  may 
be  detected  on  the  west  or  Innishowen  shore,  from  Moville  to  Port-a- 
dorus ;  on  the  eastern,  or  Derry  shore,  the  effects  of  upheaval  assume 
larger  dimensions.  Evidence  of  subsidence  is  also  present.  Thus,  on 
the  west  strand,  near  Portrush,  there  has  been  found  a  large  quantity 
of  hard  flaky  bog,  which,  lying  below  high-water  mark,  is  laid  bare  by 


*  Oidnance  MSS.,  Fermanagh,  Letters,  p.  41. 


SiGERSON — On  the  Physical  Oeography  of  Ireland.         19 

the  waves.  "Every  storm,*'  writes  Captain  Portlock,  "breaks  up  a 
new  portion  of  it,"  covered  though  it  be  with  sand  and  gravel,  where 
not  denuded.  The  presence  of  such  a  bog,  which  must  have  been  formed 
free  and  above  the  waves,  proves  that  the  land  here  has  sunk.  As  it 
contains  leaves,  nuts,  rotten  wood,  and  the  elytra  of  beetles,  it  is  plain 
that  both  animal  and  vegetable  life  abounded  where  now  nothing 
is  heard  but  the  roar  of  fiUling  billows. 

Evidence  of  elevation  is  seen  in  the  calcareous  clays,  containing 
marine  shells,  which  have  been  found  at  heights  varying  from  one 
hundred  to  four  hundred  and  fifty  feet  above  the  sea.  One  curious  in- 
stance is  the  bowl-shaped  hollow,  north  of  Portrush,  explored  by  Mr. 
James  Smith ;  it  is  ten  feet  only  above  sea-level,  and  contains  a  large 
quantity  of  sand  mixed  with  vaiious  marine  shells.  "  This  shelly 
deposit,"  writes  Mr.  Smith,  "  seems  to  have  been  a  sheltered  bay,  into 
which  the  shells  have  drifted,  with  a  small  admixture  of  land  shells 
washed  down  by  floods."  In  the  letters  descriptive  of  Magilligan, 
which  its  rector,  the  Rev.  Robert  Innes,  published  in  1725,  the  peculiar 
physical  appearance  of  the  locality  was  noted.  Although  he  wrongly 
cited  the  Deluge  as  the  cause  of  what  he  described,  his  description  is 
accurate  and  valuable.  The  evidence  of  upheaval  was  recognised  by 
him.  "  That  this  land,"  he  wrote,  "was  formerly  sea,  I  tlunk  there 
is  sufficient  reason  to  believe ;  for  along,  at  the  foot  of  the  mountain  and 
all  the  coast,  is  the  old  bank  to  be  seen,  to  which  the  sea  hath 
formerly  flowed,  at  the  foot  of  which  everywhere  there  is  sea-sand  and 
shells  to  be  dug  up."  "The  lowland  of  Magilligan,"  he  adds,  "is 
divided  into  ridges,  or,  as  we  call  them,  dryms  [properly  druim]  of  sand, 
from  one  hundred  to  five  hundred  yM^s  broad,  highest  in  the  middle 
and  sloping  on  each  side  to  marshy  ground,  which  we  call  misks,  com- 
monly as  broad  as  the  dryms ;  the  dryms  are  generally  from  six  to 
twelve  feet  higher  than  the  misks,  but  on  the  north  side  (next  the 
ocean)  the  dryms  and  misks  are  narrower,  and  some  of  the  dryms  thirty 
or  forty  feet  higher  than  the  misks.  Both  the  dryms  and  misks  are 
parallel  almost."  The  cause  of  these  (the  result  of  the  action  of  sea 
and  winds  and  of  seismical  elevation)  he  considered  to  be  the  Deluge. 
He  notes  that,  owing  to  water-action  as  then  going  on,  land  had  lost 
a  hundred  yards  within  a  man's  memory.  And  he  reports  an  interest- 
ing local  tnidition,  saying,  "  if  we  can  make  anything  of  Irish  fables, 
the  flats  of  Lough  Poyle,  which  extend  in  some  places  a  full  league, 
have  been  formerly  part  of  this  land." 

If  the  "  eruption  "  of  Lough  Foyle,  recorded  in  the  annals,  were 
an  irruption  of  the  sea,  much,  if  not  all,  of  its  present  basin  may  have 
been  dry  land.  It  would  seem  necessary  that  the  river  Foyle  should 
have  followed  its  present  direction ;  but,  in  fact,  that  need  not  have 
been.  The  valley  of  Pennybum,  which  crosses  the  isthmus  of  Innish- 
owen,  a  little  to  the  north  of  Derry,  and  which  Captain  Portlock  accu- 
rately reports  as  "exhibiting  a  channel  so  natural  and  well-defined 
that  it  is  impossible  to  resist  the  feeling  of  being  in  (the  bed  of)  a  river 
or  strait " — this  valley  I  proved  to  have  been  a  water-passage  in  recent 


20  Proceedings  of  the  Royal  Irish  Academy. 

times.  Within  three  hundred  years,  the  waters  of  the  Swilly  and 
Foyle  were  connected  by  it.  Sviiat  1  would  here  add  is,  that  in 
remote  times  the  river  Poyle  itself  (going  partly  or  wholly  by  the 
western  side  of  Derry  Hill)  has  passed  through  tlus  valley  into  Lough 
Swilly.  Though  farther  geological  investigation*  is  required  to  de- 
termine the  accuracy  of  this  supposition,  it  receives  support  from  the 
physical  appearance  of  the  district,  and  from  the  gradual  drying  up  of 
the  valley-channel,  when  the  Foyle  found  another  vent.  The  most 
ancient  map  of  Ireland  shows  only  one  lough  (Swilly)  in  this  district, 
and  the  ancient  chronicles  do  not  notice  the  existence  of  that  great 
sheet,  now  known  on  the  map  as  Lough  Foyle.  They  did,  indeed, 
make  use  of  the  name,  but  it  was  applied  to  a  large  lake  (now  obli- 
terated) which  I  proved  to  have  spread  out  its  waters  between  Strabane 
and  Derry.  The  river  which  passes  through  the  alluvial  deposits  that 
filled  the  lake,  like  a  current  through  a  frozen  sea,  still  retains  the 
name  of  Lough  Foyle,  and  when  swollen  by  floods  resumes  some  of  its 
former  sway  over  the  submerged  flats. 

Passing  to  another  question,  the  eruption  of  Lough  Neagh,  there 
is  here  also  to  be  found  geological  evidence  in  support  of  the 
statement  of  our  ancient  chronicles,  which  asserted  that  it  was  formed 
suddenly  and  (to  them)  mysteriously.  "  Lough  Neagh,"  Captain 
Portlock  remarks,  **  is  itself  apparently  the  result  of  a  great  crack  or 
subsidence  of  the  strata." 

It  only  remains  to  say  that  evidences  of  upheaval  are  visible 
in  the  deposits  reaching  up  the  Dublin  Mountains,  in  the  levels 
along  the  Lee  above  the  City  of  Cork,  and  southwards  in  the  raised 
beaches  of  Kerry ;  whilst  proof  of  subsidence  is  found  in  the  fact, 
communicated  by  Professor  W.  K.  Sullivan,  that  ancient  bog  and 
forest  stretch  out  beneath  the*Bea,  off  the  coast  of  Waterford. 

The  more  the  question  is  investigated,  therefore,  the  more  do 
proofs  abound  to  demonstrate  that,  in  ancient  times,  this  island  was 


*  Having  established,  in  a  Paper  entitled  **  Discovery  of  Fish  Remains  in  theallavial 
cliiy  of  the  Kiver  Foyle,  &g.,'*  the  insulation  of  Innij»huwen,  I  pointed  out  that  the 
eschcatment  map  of  1609  showed  another  channel  connecting  the  Foyle  and  Swilly, 
running  from  ••  Cargan  "  (now  Carrigan)  to  *'Kilmacatrem  Castle,"  and  that  Malin  wa» 
insulat^.  This  was  but  briefly  noticed,  as  corroborative  evidence  was  not 'then  accessi- 
ble. Since  that  time  I  have  gone  over  the  locality,  and  found  confirmation  of  the  map 
in  the  conformation  and  character  of  the  soil.  Tlie  former  insulation  of  Malin  is  very 
evident,  though  at  present  the  water  channel  is  occupied  by  a  great  bog.  The  substratum, 
however,  is  either  potter's  clay  or  gravel.  The  ancient  channel  or  strait  ran  between 
Culdaff  and  Malin  town,  a  distance  of  about  three  miles  in  a  direct  line,  being  somewiiat 
shorter  than  the  isthmus  at  Pennyburn.  Interi^persing  the  vast  bog  which  has  now 
largely  occupied  its  place,  are  oases  of  clay  land,  formerly  islands,  and  about  midway 
on  the  moor  is  a  village  whose  name,  Aughnaclea,  signifying  "Ford  of  Hurdles,** 
indicates  the  former  presence  of  water.  As  the  channel  miut  have  existed  in  1609,  when 
the  cschoatment  map  was  made,  aud  as  a  great  bog  has  since  been  formed,  we  have  here 
desirable  and  valuable  data  for  arriving  at  the  rate  of  bog  growth.  Plainly  this  great  bog 
cannot  be  many  centuries  old. —  Vide  Pioc.  H.  Irish  Acad.,  Vol.  I.,  Ser.  2,  Science, 
p.  iM2. 


SiGERSox — On  the  Physieal  Geography  of  Ireland,         21 

greatly  subjected  to  the  influence  of  seismical  action.  The  following 
conclusions  may  be  drawn  : — 

1st.  llie  descriptions  given  in  the  annals^  or  woven  into  legends, 
of  the  various  physical  phenomena  mentioned  coincide  closely 
with  what  we  know,  in  a  sure  manner,  of  the  results  of  earthquake 
action  in  modem  times. 

2nd.  The  evidence  of  earthquake  action  in  Ireland,  given  thus 
unconsciously  as  to  cause  by  our  ancient  annalists,  is  doubly  valuable 
because  of  its  proven  accuracy  and  undoubted  antiquity. 

3rd.  Our  ancient  records  form,  probably,  the  largest  collection  of 
ancient  seismical  indications  and  results  now  in  existence. 

4th.  Ireland  was,  of  old,  extremely  subject  to  the  influence  of 
earthquakes  within  historical  times. 

6th.  By  comparing  our  ancient  with  our  modem  records,  we  have 
a  means — wanting  in  most,  if  not  all,  countries  besides — of  noting 
with  approximate  accuracy  the  increase  or  decrease  of  seismical  energy 
in  a  given  area. 

When  the  great  convulsions,  tailing  off,  gradually  diminished  in 
frequency  and  intensity,  the  principal  physical  changes  which  after- 
wards took  place  were  those  attributable  to  common  causes  usually 
seen  in  operation.  In  some  cases,  by  the  gradual  silting  up  of  straits 
and  channels,  and  by  the  growth  of  bog,  islands  have  been  united  to 
the  mainland.  Instances  may  be  found  in  the  case  of  Malin,  formerly 
insulated ;  of  Innisho  wen,  formerly  insulated ;  of  the  Isle  of  Doagh,  and 
of  the  Isle  of  Inch  (both  in  Lough  S willy) ;  of  Horn  Head,  the  Isle  of 
Derry,  and  of  several  islets  on  the  north-west  coast.  According  to 
the  observations  of  Professors  Sullivan  and  O'Reilly,  the  Hill  of 
Howth  was  also  formerly  insulated. 

Alterations  in  the  physical  geography  of  the  country  have  also 
taken  place  by  the  obliteration  of  lakes,  wrought  by  deposit  of  allu- 
vium, by  evaporation,  or  by  migration  of  the  waters  of  the  lake 
ixipturing  their  boundary  (of  which  America  offers  recent  instances). 

The  following  are  the  names  of  the  lakes  whose  former  existence 
I  have  traced,  and  whose  places  are  now  occupied  by  bog  or  dry  land : 
Loch  Burran,  now  called  ''Loughaverra,''  in  the  parish  of  Ballintay, 
Antrim ;  Loch  Ore,  the  island  of  which  now  occupies  the  centre  of  a 
bog  in  the  townland  of  Monahinsha  (bog  of  the  island),  in  the  parish  of 
Corbally,  Tipperary ;  Lough  Foyle,  now  represented  by  a  river  (still 
called  "Lough  Foyle"),  extending  between  Strabane  and  Derry; 
Loch  Gabair,  now  Logore,  in  Meath ;  Loch  Gair,  now  Lough  Gur^ 
Co.  Limerick,  still  a  lake,  but  of  diminished  size,  as  its  island  has  be* 
come  attached  to  the  mainland ;  Loch  Laeghaire,  south  of  Strabane. 
These  lakes  became  effaced,  quietly,  by  evaporation  and  deposit ; 
others  burst  bounds  and  ran  off.  Thus  the  Four  Masters,  and  Nonnius, 
relate  that,  a.  d.  848,  Loch  Laeigh,  in  Mayo,  **  migrated,"  and  **  ran 
off  into  the  sea."  Again,  a.d.  1054,  Lough  Syorun»  in  Cavan,  "mi- 
prated  in  the  end  of  the  night  of  the  Festival  of  Michael,  and  went 
int9  the  river  Feabail,  which  was  a  great  wonder  to  all."     Finally, 


22  Proceedings  of  the  Royal  Irish  Academy. 

having  searched  in  vain  for  a  Loch  Monann,  mentioned  in  the  Annals, 
A.  D.  1544,  I  discovered  a  townland  of  that  name  on  the  Escheatment 
map,  1 609.  The  lake  no  longer  exists,  but  the  ravine  known  as  Stra- 
bane  glen,  which  extends  from  the  townland  (whose  ancient  name  is 
now  obsolete),  appears  to  furnish  the  channel  by  which  it,  also, 
**  migrated." 

III. — On  a  Cause  op  the  Bcoyancy  op  Bodies  of  a  Greater  Dkn- 
8ITT  THAif  Water.     By  George  Sigekson,  M.  D.,  Ch.  M.,  F.  L.  S. 

[Rend  June  23,  1873.] 

In  considering  the  phenomena  attendant  on  the  buoyancy  of  bodies  of 
a  greater  density  than  water,  observers  appear  to  have  confined  their 
attention  exclusively  to  the  relations  of  Uiose  bodies  and  the  fluid  on 
which  they  were  placed.  In  other  words,  they  limit  their  observation 
to  the  visible  substances.  From  certain  ifacts  which  have  come  under 
my  notice,  the  results  of  some  experiments,  it  seems  to  me  that  a  dis- 
tinct and  important  part  is  played,  in  the  causation  of  such  phenomena, 
by  an  agent  hitherto  unsuspected,  because  invisible  to  the  eye,  namely, 
the  atmospheric  air. 

It  is  known  that  when  small  bodies,  such  as  needles,  grains  of 
sand,  seeds,  and  so  forth,  are  placed  gently  on  the  surface  of  water, 
they  will  float,  although  their  density  is  greater  than  water. 

On  examination,  it  is  found  that  they  rest  partly  in  the  water, 
partly  in  a  depression  of  the  surface,  which  surrounds  them  with  a 
convex  ridge.  To  explain  their  buoyancy  in  such  circumstances,  refe- 
rence has  been  made  to  the  viscosity  of  the  fluid,  or  tenacity  of  molecular 
cohesion,  to  a  repulsive  force  supposed  to  be  exerted  in  some  way  by 
the  floating  body  which  repels  the  water,  and  to  capillarity.  When  we 
admit  the  viscosity,  for  whatever  it  is  worth,  it  is  found  insufficient  to 
account  for  the  buoyancy;  as  for  the  others,  they  are  explanations  which 
require  themselves  to  be  explained. 

What  is  the  actual  physical  condition  of  the  floating  object? 

Firstly:  It  is  partially  immersed  in  water.  It  loses  thus  part  of  its 
weight,  equal  to  the  weight  of  liquid  which  it  displaces.  Two  forces 
are  recognised  in  action:  its  weight  acting  vertically  downwards,  and 
the  resultant  of  fluid  pressures  acting  vertically  upwards.  There  is,  I 
allege,  another  force.  Secondly :  The  body  is  also,  be  it  remarked,  not 
only  partially  immersed  in  water — it  is  also  partially  immersed  in  air. 
Now,  to  the  forces  which  come  into  action  through  thu  medium,  in  co- 
operation with  those  described,  I  attribute  the  buoyancy  of  such  bodies. 

The  adhesion  of  the  air  to  a  body  surrounds  it,  as  it  were,  with  an 
atmosphere  of  its  own.  This  film  of  air  remains  in  intimate  contact 
with  it  until  replaced,  as  it  may  be,  by  some  other  medium  of  greater 
adhesive  power.  To  describe  this  air- wetting  a  word  is  required,  if  aera- 
tion will  not  serve  :  it  seems,  however,  a  condition  perfectly  analogous 
to  hydration  or  water-wetting.     To  a  body  wetted  in  water  a  layer 


SiGERSON — Buoyancy  of  Bodies  Denser  than  Water,        23 

of  water  attaches  with  an  adhesive  force  greater  than  the  force  of 
cohesion  which  keeps  the  molecules  of  water  together ;  for,  if  we  raise 
such  a  body  out  of  the  fluid  there  is  rupture  of  this  force,  as  a  film  of 
water  will  still  adhere  strongly  to  the  removed  body.  The  adhesion 
of  air  to  an  aerated,  air-wetted,  or  (as  commonly  said)  dry  body  is 
likewise  strong,  in  many  cases,  though  not  so  open  to  remark.  To  a 
large  number  of  bodies,  which  come  easily  under  our  notice,  water 
adheres  more  yigorously  than  air;  they  are  readily  water- wetted. 
But  there  are  also  some  to  which  the  air  appears  to  adhere  with  greater 
tenacity. 

When  an  aerated  body  is  placed  on  the  surface  of  water,  its  atmo- 
sphere, that  is  to  say,  the  film  of  air  which' surrounds  it,  tends  to 
increase  its  volume  without  increasing  its  weight.  Being  much  lighter 
than  water,  the  adhering  air  will,  therefore,  co-operate  with  other 
causes  to  prevent  the  body  from  sinking  and  to  keep  it  buoyant,  as  long 
as  the  force  of  air-adhesion  endures. 

In  order  to  demonstrate  that  air-adhesion  supplies  a  force  potent 
enough  to  act  in  the  manner  alleged,  it  is  only  necessary  to  take  some 
small  bodies,  vv^hose  density  in  relation  to  size  shall  not  be  very  great, 
but  amply  sufficient  to  cause  sinking  when  water-wetted.  In  experi- 
menting, I  have  found  it  most  convenient  to  use  seeds,  taking  difierent 
kinds  and  sizes,  generally  round  in  form,^sucb  as  the  seeds  of  Everlast- 
ing Pea  {Lathyrus  lattfoUus),  of  Sweet  Pea  {Lathyrus  odoratus),  of 
mustard,  turnips,  &c.  If  water-wetted,  any  of  these  objects  will  sink 
at  once,  but  when  placed  on  the  surface,  dry  (or  aerated),  they  float 
Thei«  they  illustrate  aU  the  phenomena  of  "capillarity"  and  ** attrac- 
tion" known  in  such  cases. 

Whilst  the  under  surface  and  sides  have  become  water- wetted,  there 
is  a  dry  patch  above — ^in  other  words,  to  a  portion  of  the  upper  surface 
the  air  stiU  adheres.  A  comparatively  smart  blow  may  be  given  here, 
without  causing  such  a  body  to  sink — it  will  go  down  a  little  and  re- 
bound ;  but  if  it  be  lightly  touched  (say  a  turnip- seed  by  a  flat-ended 
pencil),  so  that  the  water  cover  it,  it  sinks  at  once.  That  is  to  say — 
^  air-adhesion  has  been  broken,  the  complementary  cause  of  its 
buoyancy. 

If  we  now  take  some  dry  or  aerated  seeds  and  drop  them  into  the 
water  from  various  distances,  say  about  a  foot  high,  the  force  of  the 
air-adhesion  becomes  strikingly  and  beautifully  manifested.  It  will 
be  immediately  remarked  that  numbers  of  the  seeds  as  they  sink  in  the 
water  have  small  globes  of  air  adhering  to  them.  We  may  have  the 
following  cases  occurring: — 

1.  The  body,  falling  from  a  height,  may  retain  a  globule  of  air  ad- 
hering to  it,  insufficient  to  counteract  its  own  weight  and  the  water- 
pressure.  It  remains,  therefore,  at  the  bottom,  and  with  it  remains 
the  air-globule.  The  force  of  adhesion  here  manifested  is  stronger  than 
that  which  solicits  the  air  to  ascend  to  the  surface. 

2.  The  body  may  carry  down  with  it  a  globule  sufficiently  large  to 
raise  it  from  the  bottom,  assisted  perhaps  by  the  rebound,  if  the  shock 
be  not  strong  enough  to  sever  the  adhesion  and  set  the  globule  iree. 


24  Proceedings  of  the  Royal  Irish  Academy, 

3.  The  body  may  take  with  it  adhering  air  sufficient  to  serve  as 
counterpoise  (if  I  may  use  the  words)  to  its  own  weight  in  water,  and 
thus  it  may  float  completely  immersed  in  the  water,  surmounted  by  an 
air-globule. 

4.  The  amount  of  air  adhering  may  be  so  great  as  to  prevent  the 
complete  descent  of  the  bedy,  to  hinder  it  from  diving  much  below  the 
surface,  and  to  rapidly  draw  it  up  again  to  the  surface.  In  such  a 
case,  the  adhesion  of  ^e  air  to  the  object  is  evidently  strong  enough 
to  completely  resist  the  weight  of  the  object  in  water,  and  to  partially 
resist  the  force  acquired  by  a  fall  from  a  distance,  relatively  con- 
siderable. 

The  air-adhesion  may  be  broken  in,  at  least,  three  ways.  First, 
by  the  blow  the  object  receives  on  striking  the  surface  in  its  descent, 
BO  that  it  may  go  down  without  any  globule,  or  if  the  effect  be  partial, 
with  a  small  one.  Second,  by  the  blow  received  on  reaching  the  bottom. 
Third,  by  the  shock  when,  rising  to  the  surface,  the  air  globule  suddenly 
expands.  On  account  of  the  narrowness  of  the  base  of  connexion,  in 
some  cases,  the  adhesion  may  be  quietly  severed,  by  water-pressure. 

In  cases  where  a  body  is  quite  buoyant  in  the  water,  on  ^account  of 
the  attached  globule,  it  may  be  readily  shown  that  the  base  of  con- 
nexion forms  an  adhesion  area  large  enough  to  sustain  this  body  at  the 
surface,  when  the  upper  air  shall  replace  the  globule.  This  is  demon- 
strated, as  in  case  2,  by  gently  elevating  the  body  to  the  surface,  and 
allowing  the  globule  to  open  into  the  upper  air :  or,  by  observing,  as 
in  cases  3  and  4,  the  ascent  of  bodies  drawn  up  by  their  globules  to 
the  surface,  where,  if  the  shock  of  the  expansion  of  the  globule  do  not 
sever  the  adhesion,  they  will  float.  In  such  cases,  the  area  of  aerated 
space  remaining  the  same,  the  adhesion  of  the  upper  air  now  manifestly 
sustains  the  body  in  a  buoyant  state. 

In  this  condition  buoyant  bodies,  whose  density  is  greater  than 
water,  present  themselves  usually  to  observers.  From  the  facts  related, 
it  follows  that  they  are  sustained  in  this  position,  partly  by  the  ad- 
hesion of  the  atmospheric  air. 

The  incidents  of  this  demonstration  suggest  some  remarks  and  infe- 
rences. When  we  withdraw  a  glass  rod  or  a  wetted  body  from  water, 
the  drop  which  adheres  shows  that  in  such  cases  the  force  of  adhesion 
between  the  liquid  and  solid  is  greater  than  the  force  of  cohesion  be- 
tween the  molecules  of  the  liquid.  Conversely,  when  we  let  pass  an 
aerated  body  from  the  air  into  the  liquid,  the  globule  or  drop  of  air 
which  adheres  to  it,  proves  that,  in  such  cases,  the  force  of  adhesion 
between  the  gas  and  the  solid  is  greater  than  the  force  of  cohesion 
between  the  molecules  of  the  gas.  We  have  seen  that  it  is  also  strong 
enough,  in  certain  cases,  to  sustain  a  weight  as  great  as,  or  greater 
than,  the  weight  of  a  given  body,  mintis  the  weight  of  the  volume  of 
water  displaced,  and  that  it  is  potent  enough  to  resist  the  action  of  the 
forces  which,  when  a  body  is  let  fall  from  a  height  into  water,  tend  to 
separate  globule  and  body,  sending. the  former  upwards  and  the  latter 
down. 

The  force  of  adhesion  between  air  and  solid  is,  therefore,  for  many 


SiGERSON — Buoyancy  of  Bodies  Denser  than  Water,        25 

reasons,  a  very  tangible  and  noteworthy  force,  which  cannot  be  elimi- 
nated from  consideration,  in  such  and  similar  problems,  without  inac- 
curacy. » 

This  being  so,  it  may  become  necessary  to  revise  certain  definitions 
or  statements  of  laws  in  physics,  in  order  that  the  presence  of  this  force 
may  be  recognised  where  it  exists.  Thus,  it  is  mentioned  that  a  float- 
ing body  is  acted  on  by  two  forces — ^its  weight,  and  the  resultant  of 
fluid  pressure.  To  this  it  may  be  necessary  to  add,  that  a  third  force, 
adhesion  of  air,  exists,  and  becomes  a  perceptible  agent  in  the  case  of 
amaU  floating  bodies. 

Again,  in  the  curving  of  liquids  in  contact  with  solids,  the  presence 
of  air  is  altogether  unrecognised,  and  only  the  forces  acting  through 
the  visible  media  are  mentioned.  Thus  we  are  told  that  when  a  solid 
is  placed  in  a  hquid  which  wets  it,  the  liquid,  as  if  not  subject  to  the 
law  of  gravitation,  rises  against  the  side  of  the  solid  and  becomes  con- 
cave. It  is  added  that  where  the  solid  is  not  wetted  by  the  fluid,  the 
latter  is  depressed  and  becomes  convex.  Kow,  it  appears  to  me,  from 
the  foregoing  facts,  that  this  should  be  re-stated  in  the  following  manner: 
When  an  aerated  solid  is  placed  in  a  liquid  whose  adhesive  power  is 
greater  than  the  adhesive  power  of  air,  as  regards  such  solid,  the  air 
is  partially  displaced,  the  fluid  becoming  concave  and  the  air  convex. 
But  when  an  aerated  solid  is  placed  in  a  liquid  whose  adhesive 
power  is  less  than  the  adhesive  power  of  air,  as  regards  such  solid, 
then  the  water  is  partially  displaced  by  the  air  and  becomes  convex, 
whilst  the  latter  grows  concave.  The  concave,  in  either  case,  bounds 
the  outward  side  of  a  wedge  of  advancing  substance,  whose  inner  side 
is  applied  to  the  solid. 

It  follows  that  it  would  probably  be  well  to  modify  the  manner  in 
which  the  first  law  of  Gay  Lussac  is  expressed,  in  order  to  recognise 
the  presence  of  air-adhesion  as  a  power.  As  it  stands,  the  law  is : 
"When  a  capillary  tube  is  placed  in  a  liquid,  the  liquid  is  raised  or 
depressed  according  as  it  does  or  does  not  moisten  the  tube."  I  would 
read  it  thus :  '*  When  a  capillary  tube  is  placed  in  a  liquid,  the  liquid 
is  raised  or  depressed  according  as  its  adhesive  power  is  greater  or  less 
than  that  of  the  air.'' 

These  suggestions  are  offered,  with  diffidence,  to  the  consideration 
of  physicists,  as  there  may,  in  such  cases,  be  forces  operative  which 
have  not  yet  come  under  review.  But,  lest  I  should  be  supposed  to 
have  overlooked  the  obvious  objection  that  Gay  Lussac' s  law  is  said  to 
hold  good  in  vacuo,  and  therefore  in  the  absence  of  air,  I  must  add 
that  it  is  confessed  that  the  air-pump  gives  no  absolute  vacuum. 

The  air  becomes  exceedingly  rarified,  but  a  perceptible  quantity  is 
left.  And,  when  it  is  remembered  that,  from  the  facts  now  experi- 
mentally demonstrated,  it  was  shown  that  the  adhesion  of  air  to  a 
solid,  in  a  given  case,  is  greater  than  the  adhesion  of  air-molecules 
between  themselves,  it  will  be  admitted  that  the  instruments  used  in 
an  air-pump  may  be  covered  with  an  adhering  film  of  air,  until  dis- 
placed by  water,  operative  in  causing  the  phenomena  recorded. 

B.  I.  A.  PROC. — »EB.  II.,  VOL.  II.,  SCIENCE.  £ 


26  Proceedings  of  the  Royal  Irish  Academy, 


IT. — On  boms  gbnebal  Fobmuub  fob  the  Solittion  of  Alofjbraical 
Equations  of  the  Third  Deobee,  &c.  By  J.  R.  Young,  for- 
merly Professor  of  Mathematics  in  Belfast  ODllege. 

[Read  May  25, 1874.] 

A  gbnebal  formula  for  the  solution  of  any  equation  of  the  second  de- 
gree is  readily  obtained  by  means  of  the  well-known  expedient  of 
completing  the  square,  I  am  not  aware  that  any  algebraist,  as  yet,  has 
investigated  a  ]ike  general  formula  for  the  solution  of  an  equation  of 
the  third  degree;  that  is,  by  the  similar  preliminary  expedient  of 
completing  the  cube.  It  is  the  main  purpose  of  the  present  Paper  to 
establish  such  a  general  formula;  previously,  however,  to  which,  it 
will  be  necessary  to  dispose  of  the  two  following  special  cases,  that 
is  to  say,  to  prove  that — 
(1)  Whenever  in  an  equation  of  the  third  degree, 

A^  +  A^  +  AiX  +  -4o  «  0, 

either  the  first  triad  of  the  coefficients,  A^,  A^,  J  i,  or  the  second  triad, 
Af,  Ai,  A^  furnishes  the  relation  of  equality 

3-4,  Ai  =  -4a«,  or  3-4,  A^^Ai* [1] 

the  first  member  of  the  equation  can  easily  be  converted  into  a  complete 
cube,  and  thence  a  general  expression  for  the  root  x  be  deduced. 

1.  Let  it  be  the  first  of  the  conditions  [1]  which  has  place,  and  let 
a  quantity  ^  be  so  determined  that,  by  the  addition  of  ^  to  J  09  the 
second  condition  also  may  be  satisfied  ;  namely,  the  condition 

SA,(Ao  +  k)  =  A,\' 

in  order  to  which,  the  value  of  k  must  evidently  be 

so  that  this  quantity  being  added,  there  results  the  equation 

A  * 

A^  +  A^  +  AiX  +  ^  =  k ; 

and,  consequently,  dividing  by  A^  and  taking  account  of  the  stipulated 
condition,  we  shall  have 

-4:-Ki)'"(j-:)'-i 


Young — Algebraical  Equationa  of  the  Third  Degree,  Sfe.     27 
the  first  member  of  which  equation  is  a  complete  cube.    Hence, 

or, 

2.  Suppose  now  that  it  is  the  second  of  the  conditions  [I]  that  is 
satisfied;  then  the  first  condition  also  will  he  satisfied,  provided  a 
quantity  ^  be  so  determined,  as  that,  when  it  is  added  to  A»,  the  con- 
dition 

may  be  satisfied ;  that  is  to  say,  provided  we  make 

8^1 


p-^-^^; 


since  this  yalne  off,  when  added  to  the  coefficient  of  «*,  will  eonyert 
the  proposed  equation  into 

A  ■ 

~  x*-^A^  +  A^  +  -40=*  P«*- 

SA 
Hence,  multiplying  by  -~,  and  observing  from  the  stipulated  con- 

'^^  A? 

dition  [1]  that  Aq  is  the  same  as  —p  ,  we  have 

''*4:-*Ki)'*(t)'-"2?'" 

the  first  member  of  which  equation  is  a  complete  cube.    Consequently, 


or. 


,  =  4;^j,.vd^iiii£'|....  [3] 


28  Proceedings  of  the  Royal  Irish  Academy. 

(2)  I  have  shown  in  a  formercommunication  to  the  Academy  "  Pro- 
ceedings," vol.  X.,  p.  373),  that  if  any  cubic  equation  be  represented  by 
P  =  0,  and  the  first  and  second  functions  derived  from  P,  by  Q  and 
P*  respectively,  the  equation  Q*  -  3PP'  =  0  will  always  be  a  quadratic 
equation.  Let  one  of  the  roots  of  this  equation — either  root  indiflferently 
— be  represented  by  r ;  and  let  each  root  of  the  proposed  cubic  equation 

P  -  A^  +  ilja;'  +  AiX  +  Aq^  0 

be  diminished  by  r.     The  resulting  transformed  equation  will  be 

the  second  triad  of  coef&cients  of  which  fulfils  the  second  of  the  two 
conditions  [1];  and,  consequently,  by  the  formula  [3],  we  have  for 
x'  the  expression 

^,_    ZA^-^2A^+A,  ^  (       l/A^^-SA,A.^ 
3A,r  +  A:,  '     \  (3^r+^,)= 

Therefore,  multiplying  numerator  and  denominator  of  the  fraction 
under  the  radical  sign  by  SA^  -f  J.,,  and  remembering  that  x  =  r  +  a/, 
we  shall  have  for  x,  the  expression, 

8ii3r»4-2^ar-f  ^1 

*"^"  3^3r  +  ^,-^{(^a»  -  SA,A,){3A,r-^A,)y  (^) 

And  this  Is  a  general  symbolical  formula  for  the  three  roots  of  the 
cubic  equation  P=  0. 

(3).  Whenever  r,  determined  as  already  explained,  is  real,  we  may 
bo  certain  that  only  one  of  the  three  roots  of  the  cubic  is  a  real  root, 
since  a  cube  root  has  but  one  real  value  ;•  and  this  real  root  the  for- 
mula (4)  wiU  enable  us  to  determine,  by  introducing  into  that  formula 
the  real  cube  root  only  of  the  number  under  the  sign  \/ ;  and  the  two 
imaginary  roots  of  the  equation  will  be  expressed  by  introducing  into 
the  formula  the  two  imaginary  cube  roots  of  the  number  under  the 
sign  'v/,  after  the  real  cube  root  of  that  number  has  been  determined. 
But  whenever  r  is  imaginary,  then,  although  we  know,  in  that  case, 

*  And  in  this  manner  is  the  truth  of  the  second  of  the  general  properties,  noticed 
at  Article  5  following,  otherwise  proved :  the/r«^  of  those  properties  showing  that, 
if  r  be  imaginary,  the  above  expression  for  Xy  notwithstanding  its  being  then  so 
encumbered  with  imaginary  quantities,  must  have  all  its  values  real  values.  More- 
over, this^r^^  of  the  properties  at  (6)  may  also  be  deduced  from  the  general  for- 
mula above ;  for  since,  as  just  seen,  two  roots  of  the  equation  must  be  ima^nary 
whenever  r  is  real^  the  roots  must  all  be  real  when,  and  only  when,  r  is  imagmary. 


Yov^Q— Algebraical  Equations  of  the  Third  Degree^  Sfc.    2? 

that  all  the  roots  of  the  cubic  equation  must  be  real  roots  {**  Proceed- 
ings/' Tol.  X.,  page  374)  ;  yet  we  have  no  means  of  extricating  these 
real  values  from  &e  imaginary  forms  under  which  they  lie  concealed. 
(See  Note  at  the  end  of  this  Paper). 

The  more  restricted  formula  of  Cardan  is  in  the  like  predicament. 
For  the  application  of  this  formula,  the  equation  must  be  reduced  to 
the  form 

The  expression  for  x,  as  furnished  by  the  formula  (4),  when  the  pro- 
posed equation  takes  this  more  simple  form,  is 

This  expression  is  •*  irreducible  "  under  precisely  the  same  circum- 
stances that  the  expression  of  Cardan  is ;  namely,  whenever  27 Aq* 
+  4^,*<  0 ;  or,  which  is  the  same  thing,  whenever 


Br>(f)' 


This  maybe  easily  proved  by  deducing  the  equation  Q*--3PP'=0, 
and  thence  the  expression  for  r,  firom  the  incomplete  cubic  equation 
P  =  0:  thus: 

F=^x^-k-AjX±Ao^ll 
Q  =  3a;»+u4i 
P'  =  3x, 

from  which  we  get  the  quadratic  equation, 

Q»-  3PP'  =  -  SA.x'-  9^oa?  +  ^i«  =  0  ; 

,  -9^±^{(9^o)'^•12^,»} 

showing  that  r  is  imaginary,  and,  therefore,  all  the  roots  of  P«  0  real 
whenever,  and  only  whenever 

8Uo' +  124 1»  <  0  ;  or  whenever  27i4o' +  4i4i»  <  0 ; 

under  which  condition  the  formula  (5),  like  that  of  Cardan,  is  irre- 
ducible to  a  finite  numerical  expression  for  the  real  roots  of  the  equa- 
tion iJ  =  0,  which  shall  be  unencumbered  with  imaginary  quantities.  [It 


30  Proceedings  of  the  Royal  IrUh  Academy. 

is  obvious  that  the  foregoing  condition  can  never  be  satisfied  anless  the 
coefficient  Ax  is  negative.] 

Whether,  in  the  reducible  cases  of  the  equation  re*  +  ^,ar  +  i4,  =  0, 
that  is,  in  the  cases  in  which  27 Aq*  +  4^i'  is  not  less  than  zero,  the 
formula  [5]  may,  or  may  not,  advantageously  replace  the  old  formula 
of  Cardan,  must  be  left  for  the  discrimination  of  algebraists  to  deter- 
mine. Few  persons,  however,  are  likely  to  prefer  a  formula  to  the 
method  of  continuous  approximation,  whenever  the  numerical  values  of 
the  roots  of  an  equation  of  higher  degree  than  the  second  degree  are 
thq  only  objects  of  search. 

(4.)  Whenever  it  happens,  in  this  case  of  an  incomplete  cubic  equa- 
tion, that  (9-4o)"  +  12^1*,  or,  which  is  the  same  thing,  that  27-4o" 
+  4^1*  is  zerOf  the  two  values  of  r^  as  expressed  in  the  foregoing  for- 
mula, will  be  equal  values ;  and,  as  already  proved  in  the  Paper  before 
referred  to,  these  are  also  two  roots  of  the  cubic  -P  ==  0  ;  hence,  when- 
ever this  condition  has  place,  the  incomplete  cubic  equation  has  a  pair 
of  equal  roots,  each  of  these  being, 

*'^6^i  ""^Ai' 

It  may  be  well  to  observe  here  that  the  case  of  equal  roots  in  any 
cubic  equation,  is  excluded  from  the  general  investigation  at  article  (2). 
The  transformed  equation,  in  ^,  of  which  the  first  three  terms  are 

A^*  +  {ZA^r  +  At)al*  +  (Sidsr*  +  2.4^  +  Aiy, 

is  there  considered  to  have  a  significant  coefficient  for  its  third  term ; 
since  if  the  expression 

8-4jr»+2-48r+^i 

were  zero,  the  first  member  of  this  transformed  equation  could  not  be 
made  a  complete  cube  by  merely  modifying  the  coefficient  of  a:'*,  as, 
in  the  investigation  alluded  to,  is  assumed  to  be  practicable. 

When  the  indicating  quadratic  (Q*  -  3  FF  =  0),  as  we  may  call  it, 
has  two  equal  roots,  and,  therefore^  the  cubic  P^O  has  the  same  two 
equal  roots,  the  above- written  coefficient  must  be  zero  ;  in  which  case 
the  transformed  equation  becomes  simply 

^,a:'»+(3i4sr  +  -4,>c'*  =  0, 
of  which  the  three  roots  are 

a:'  a  0,  a/a  0,  a:' « ^: 

Az 


Young — Algebraical  Equations  of  the  Third  Degree^  8^c,     31 
and,  therefore,  those  of  the  original  equation  are 


a:»r,  x»r,  a?  =  - 


A, 
the  sum  of  which  roots  is 

2A^'¥At         At 


2r  — 


^^      a: 


as  we  know  it  ought  to  be.    In  the  case  of  the  incomplete  cubic,  con- 
sidered above,  in  which  -43=  1,  and  ^»  =  0,  this  sum  is,  of  course,  zero. 
(5.)    It   was    sufficiently  shown   in   my  former    Paper   (Article 
33),  that,  if  any  cubic  equation  P  =  0,  be  written  in  the  form, 

P=  (or"  +  Jx  +  c){x  +p)  =  0, 

in  which  a,  h,  c,  and  p,  have  any  real  values  whatever,  and  that  the 
quadratic  equation  Q*  -  ZPF*^  0,  be 

Ax^-^Bx-k^  C=0, 

the  following  relations  necessarily  have  place ;  namely, 

If  ^<4^C,  then  6«>4atf; 

and  conversely ;  from  which  relations  it  follows  that 

If-B«=4u4C;thenft»  =  4flc; 
„  ^•  =  4ac,       „    ^=4^a 

The  determination  of  the  indicating  quadratic, 

<P- SPP' =u4a:»  + ^^  +  C=0, 

in  any  individual  instance,  involves  but  very  little  calculation  ;  because, 
since  we  know  that  the  first  two  terms  of  Q'  are  always  the  same  as 
the  first  two  terms  of  ZPP\  we  need  not  take  the  trouble  to  compute 
them ;  it  is  sufficient  that  we  preserve,  in  the  multiplications,  only  the 
terms  beyond  the  first  two  terms  of  each  product. 

In  order  to  illustrate  this  by  an  example,  let  the  proposed  equation  be 

P  =  ie»-4aj»  +  8a?+2  =  0 
.-.  Q=32J»-8a:+3 
P'=3«-4 


32  Proceedings  of  the  Royal  Irkh  Acadeviy. 

3a^  -  8a:  +  3  a:*  -  44:*  +  3x  +  2 

3a»  -  8x  +  3  3x  -  4 


18ar»+64a^-48a?  +  9     9a?«+ 164;»- 12x+ 6ar- 8,  x3 
or 

822:'-4ar+9 
=  75a^-18a?>24=:  3(25a:»-6x- 8) 
.-.  C»- 3i'P'=7^-30x  +  33 c=  0, 

the  indicatiog  quadratic. 

And  since  the  roots  of  this  are  seen  to  be  imaginary,  the  equation 
indioates  a  pair  of  real  roots  in  the  cubic  P «  0 ;  and,  consequently, 
that  all  the  roots  are  real. 

.  (6.)  But  the  indicating  quadratic  may  always  be  arrived  at  in 
another  way.  This  other  method  of  proceeding  consists  in  extracting 
the  square  root  of  the  product  3PP^ ;  taking  care,  however,  that  the 
successive  terms  of  the  root  be  the  successive  terms  of  the  quadratic 
function  Q*  Uuder  this  condition,  the  remainder^  at  which  we  shall 
arrive,  when  taken  with  changed  signs,  and  equated  to  zero,  will  always  . 
be  the  indicating  quadratic.  Thus,  taking  the  example  just  given, 
where  the  complete  product  ZPP  is 

3PP'=  9a:*-  48a:»  +  75a*  -  18a;  -  24, 

and  extracting  the  square  root  in  such  way  that  the  terms  put  one 
after  another,  in  the  root-place,  may  be  Sa:"  -  Bar  +  3  ;  we  shall  find  the 
remainder,  at  the  end  of  the  operation,  to  be  -  Ta:*  +  SOar  -  33.  This 
remainder,  after  changing  the  signs  of  its  terms,  will  be  7ar»  -  30a?  +  33 ; 
which,  equated  to  zero,  will  be  the  indicating  quadratic. 

That  the  indicating  quadratic  may  always  be  arrived  at  in  this 
manner  will  appear  from  considering  that  if  we  put  ^  =  0  to  denote  this 
quadratic,  that  is,  if  Q»-3PP'  =  j,  it  wiU  follow  that  SPP'e  (?-g. 
But  in  the  square  root  operation  described  above,  ZPP'  is  equal  to 
Q*  plus  the  remainder ;  consequently,  q  is  this  remainder  taken  with 
ehiuiged  signs. 

Since  all  the  roots  of  the  foregoing  cubic  equation  are  shown  by 
the  indicating  quadratic  to  be  real  roots,  we  know  that  the  two  roots 
of  the  derived  quadratic  equation,  Q=3a:*-8a;  +  3  =  0,  must  be  sepa- 
rators of  those  three  roots ;  the  middle  one  of  the  three  lying  between 
the  two  real  roots  of  Q  =  0.  In  order  to  the  actual  determination  of 
the  numerical  values  of  the  three  roots,  the  shortest  way  of  proceeding 


•  There  is,  however,  no  necessity  to  reTcrt  to  the  expression  Q  for  the  first  two 
of  the  root  terms ;  these  same  two  terms  may  be  arriyed  at  hy  following  the  ordi- 
nary rule  for  the  extraction  of  the  square  root.  Q  need  be  referred  to  ouly  for  the 
third  term — the  absolute  number. 


Young — Algebraical  Equations  of  the  Third  Degree^  ^r.     33 

will  be  this.  Develope  the  middle  root  by  continuous  approximation  : 
we  shall  thus  arrive  at  a  quadratic  equation,  the  roots  of  which,  when 
each  of  them  is  increased  by  the  root  previously  developed,  will  be  the 
other  two  roots  of  the  proposed  cubic. 

(7.)  When  each  triad  of  the  coefficients  of  a  cubic  equation  fails 
to  satisfy  the  condition  of  imaginary  roots,  and  that  the  roots  r^,  rs, 
of  the  indicating  quadratic  equation  Q*  -  ZPP'  =  0,  are  real  and 
unequal,  the  roots  of  the  derived  quadratic  Q  =  0  will  necessarily  be 
real  roots.  One  of  these  roots,  and  one  only,  will  be  situated  in  the 
interval  [r„  r,];  and  if  the  roots  of  the  cubic  be  each  of  them  di- 
minished by  that  root  of  Q  =  0,  the  third  coefficient  of  the  trans- 
formed equation  will  vanish  between  like  signs. 

For  Ti,  r„  are  either  both  positive  or  both  negative,  inasmuch  as 
that  the  first  and  third  terms  of  the  quadratic  Q*  -  ZPF'  =  0  are  then 
both  positive  ;*  and,  therefore,  if  n  be  that  one  of  these  two  roots  which 
is  the  nearer  to  -  oo ,  the  quadratic  expression  Q*  -  3PP'  will  be 
positTve  for  every  value  of  x,  from  the  value  «  =  -  oo  up  to  the  value 
a?  =  ri ;  and  also  for  every  value  of  x,  from  the  value  j?  =  +  oo  down  to 
the  value  2r«r2.  And  since  the  expression  changes  sign  immediately 
after  the  passage  of  a  root,  and  that  the  changed  sign  remains  perma- 
nent till  the  other  root  passes,  it  follows  that  for  every  value  of  a;, 
within  the  limits  fr,,  rj,  the  expression  Q'-GPP'  must  be  negative; 
whilst  for  every  value  of  ar,  outside  those  limits,  it  must  be  positive. 
This  is  the  same  as  saying  that  for  every  value  of  x,  within  the  limits 
[fly  f^]t  the  condition  of  imaginary  roots  is  satisfied,  whilst  for  eveiy 
value  of  x^  outside  those  limits,  the  condition  fails  to  be  satisfied.  At 
either  of  the  limits,  that  is,  for  a:  =  ri,  or  for  a:  =  r„  the  condition  of 
imaginarity  is  still  satisfied ;  since,  for  either  of  these  values  of  z^ 
ZPF  =  0*.  But  when  the  roots  r^,  r^^  of  the  indicating  quadratic  are 
equal  roots,  then  we  know  that  these  same  equal  roots  belong  also  to 
the  proposed  cubic  P^  0 — the  imaginarity  disappearing  with  the  dis- 
appearance of  inequality  between  ilie  roots  [rj,  ra]. 

It  is  impossible,  therefore,  that  Q  can  vanish  between  like  signs  of 
P  and  P'  outside  the  limits  [r^  r,],  seeing  that  if  Q  could  so  vanish, 
Q^-SPP*,  for  the  value  of «  which  causes  Q  thus  to  vanish,  would  bo 
negative. 

But  one  of  the  two  roots  of  Q «  0  must  cause  Q  to  vanish  between 
like  signs  of  P  and  P' ;  consequently,  this  root  of  Q  -  0  must  lie  be- 
tween Ti  and  r-i. 

It  is  plain  that  Q  cannot  vanish  a  second  time  between  like  signs 
of  P  and  P^;  since  such  second  evanescence  would  imply  a  second  pair 
of  imaginary  roots  in  an  equation  of  only  the  third  degree.  Hence,  the 
other  root  of  Q  =  0  must  cause  Q  to  vanish  between  unlike  signs  of  P 
and  P';  so  that  when  this  evanescence  takes  place,  the  expressiou 
G*  -  ZPP'  must  be  positive. ' 


'•  Sec  the  expression  marked  (1)  at  page*  473  of  the  former  Paper. 

R.  I.  A.   PROC RER  II.,  VOL.  II.  SeiF.XCF.  F 


the  i 


34  Proceedings  qf  the  Royal  Irkh  Academy. 

(8.)  If  we  agree  to  call  that  particular  root  of  <i  =  0,  which  lies  in 
the  interval  [ri,  ra],  the  indicator  of  the  two  imaginary  roots  of  the 
ouhic  equation  P^O,  we  may  infer,  from  what  is  shown  ahove,  that 
when  the  two  roots  of  the  indicating  quadratic  are  real,  if  they  be 
positive  (they  must  always  both  have  the  same  sign),  the  indicator  is 
a  positive  number ;  and  if  they  are  negative,  the  indicator  is  a  negative 
number ;  that  ia  to  say,  the  region  in  which  the  real  roots  of  the  indi- 
cating quadratic  lie  is  the  region  in  which  the  indicator  itself  lies. 
And  we  have  seen  that  that  root  of  the  derived  quadratic  equation 
Q  «  0,  which  is  the  indicator,  is  the  only  one  of  the  two  roots  of  that 
equation  which  lies  between  the  roots  ri,  rt  of  the  equation  Q"  -  dPP' 
■>  0,  the  other  root  of  Q "» 0  being  excluded  from  that  interval. 

The  real  root,  however,  of  the  proposed  cubic  equation  P-Q  must 
lie  outside  the  interval  [r^,  ra]  ;  for,  as  shown  above^  every  value  of  x^ 
within  this  interval,  causes  the  expression  Q'  -  3PP'  to  be  negative ; 
whereas  the  value  of  x,  which  satisfies  the  condition  P^O,  reduces 
that  expression  to  Q*,  which  is  positive  ;  and,  for  a  similar  reason,  the 
root  of  the  simple  equation  P'-O  must  lie  without  the  interval. 

That  the  real  root  of  the  cubic  equation  lies  without  the  interval 

I  Ta]  is  a  conclusion  that  might  have  been  immediately  deduced  from 
I  foregoing  truth  ;  namely,  that  that  root  of  Q  =  0,  which  is  not  the 
indicator,  does  itself  lie  without  the  interval.  For,  since  this  root 
separates  the  real  root  of  the  cubic  from  the  imaginary  pair,  or  rather 
from  the  indicator  of  that  pair,  the  ieal  root  of  P^  0  must  occupy  a 
place  more  remote  from  the  interval  [r^  r,l  than  is  the  place  of  that 
root  of  Q  =:  0,  which  is  not  the  indicator  of  tne  imagincu'y  pair. 

(90  It  thus  appears  that^  without  any  preliminary  analysis  of  the 
cubic  equation  P  »  0,  we  can  always  ascertain,  from  an  examination  of 
the  quadratic  equation  Q*  -  3PP'  =  0 — 

First,  whether  the  equation  P  »  0  has  a  pair  of  imaginary  roots  or 
not. 

Second ;  if  it  have  imaginary  roots,  which  of  the  two  roots  of  the 
derived  quadratic,  Qs  0,  it  is  that  is  the  indicator  of  the  pair ;  it  is 
that  one  which  lies  between  the  two  roots  of  Q*  -  3PP  =  0  ;  and  only 
one  of  the  two  can  so  lie. 

And,  thirdly,  we  learn  that  the  real  root  of  the  cubic  always  lies 
outside  the  interval  between  the  two  roots  of  the  equation  last  men- 
tioned ;  and  from  thus  knowing  the  interval  from  which  it  is  excluded, 
the  first  figure  of  it  becomes  the  more  readily  determinable,  whenever 
all  three  of  the  roots  are  indicated,  by  the  signs  of  the  terms  of  the 
equation,  in  one  and  the  same  region. 

We  may  further  observe  here,  that  whenever  we  seek  to  deter- 
mine the  character  of  a  pair  of  doubtful  roots  in  a  cubic  equation 
P  =  0  (and  which  roots  are  indicated  in  an  interval  comprehending 
also  a  real  root  of  Q  =  0),  by  the  process  of  continuous  approximation, 
we  may  be  sure,  if  the  roots  be  imaginary,  that  the  indication  of  ima- 
ginarity  will  not  be  arrived  at  till  the  approximatiug  number  reaches 
one  or  other  of  the  values  n,  or  rt;  after  arriving  at  which,  the  condi- 


YovsQ-- Algebraical  Equations  of  the  Third  Degree,  ^e.    35 

tion  of  imaginarity  will  be  satisfied,  but  not  before ;  and  that  the  con- 
dition will  continue  to  be  satisfied  for  every  subsequent  transformation, 
throughout  the  interval  [ri,  r,],  but  not  after  that  interval  has  been 
passed  over. 

It  will  have  been  noticed  that  the  foregoing  discussion  concerns 
those  cubic  equations  only  of  which  the  given  coefficients  do  not 
themselves  supply  the  required  information  as  to  the  character  of  the 
roots ;  that  is  to  say,  those  equations  only  in  which  neither  triad  of  the 
eoefficients  satisfies  the  condition  of  imaginary  roots. 

(10.)  In  the  case  in  which  the^^  triad  of  the  coefficients  of  the 
eubic  equation  P=0  satisfies  the  condition  of  imaginarity,  the  roots  of 
the  derived  quadratic  equation,  Q  =  0,  will  be  imaginary  ;  and  the  root 
of  the  simple  equation,  /^bQ,  will  then  be  the  indicator.  But  if  the 
condition  of  imaginarity  be  satisfied  by  the  Becond  triad  of  the  coeffi- 
cients, and  not  by  the  first  also — under  which  circumstances  Q»0 
will  have  real  roots — the  roots  of  the  indicating  quadratic  will  be  real 
roots ;  and,  as  already  noticed  (Art.  6),  one  of  these  roots  will  be  posi- 
tive, and  the  other  negative ;  and,  as  before,  the  condition  of  imaginarity 
will  have  place  throughout  the  interval  between  those  roots,  and  will 
fail  to  have  place  for  all  values  outside  that  interval.  But  if  both 
triads  of  the  coefficients  satisfy  the  condition  of  imaginarity,  then  the 
first  and  last  terms  of  the  indicating  quadratic,  the  terms 

(A^-^ZA^A;^,  and  (4,>  -  S^^^ii,), 

will  each  be  preceded  by  the  negative  sign  ;  so  that  a  pair  of  imagi- 
nary roots  in  the  equation  F  -=0  would  be  implied,  even  should  the 
roots  of  the  indicating  quadrado,  Q*  -  ZPF* »  0,  be  themselves  imagi- 
nary; because,  then,  the  first  member  of  this  quadratic  would  be 
always  negative;  that  is  to  say,  the  quadratic  expression,  ZPF  -  Q^, 
would  be  positive  for  every  real  value  of  x.  As  before,  the  indicator 
of  the  pair  of  imaginary  roots  would  be  the  root  of  the  simple  equation 
P*  =  0,  this  root  being  the  value  of  a?,  for  which  a  derived  function 
ranishee  between  like  signs  of  the  two  adjacent  derived  funotiona. 


(11.)  It  is  well  known  that  each  of  the  two  roots  of  an  equation  of 
the  second  degree,  whenever  these  roots  are  unequal,  always  consists 
of  two  distinct  parts — ^the  one  being  a  rational  number,  and  the  other 
part  being  a  number,  either  positive  or  negative,  under  the  radical 
sign,  with,  usually,  a  real  factor  prefixed  to  the  radical  quantity ;  the 
rational  part  of  each  root  is  always  the  root  of  the  derived  simple 
equation. 

But  when  the  quadratic  is  raised  to  an  Equation  of  the  third  degree, 
by  the  introduction  of  a  new  simple  factor,  it  is  not  the  case  that  a 
root  of  the  equation  of  the  second  degree,  derived  from  tliis  cubic 
equation,  will  be  the  rational  part   of  each  of  the  two  roots  of  the 


36  Proceedings  of  the  Royal  Irish  Academy. 

quadratic  equation  which  enters  into  the  composition  of  the  cuhlo. 
For,  let  ar»+54:  +  tf»0  represent  any  quadratic  equation,  then  the 
derived  simple  equation  will  be  2ax  +  J  =  0 ;  and  if 


tlien, 


P  =s  (oar*  +  5^  +  c){ps  +/?), 


Xow,  if  the  value  of  x,  which  makes  2ax  +  6^0,  namely,  the  ralue 

J-  =  -  — -,  makes  also  Q  »  0,  then  we  must  have  for  that  same  value 
2a 

of  X 

which  can  be  the  case  only  when  this  latter  equation  has  equal  rooU  ; 
that  is  to  say,  only  when  the  first  member  of  it  is  a  complete  square ; 
under  which  circumstance  the  equation  P=0  must  have  two  equal 
roots.  Hence,  that  root  of  Q  =  0,  which  is  the  indicator  of  a  pair  of 
imaginary  roots  in  the  cubic  equation  P«0, — the  value  of  j?,  that  is, 
which  causes  Q  to  vanish  between  like  signs  of  F  and  F — can  never 
be  equal  to  the  real  part  of  the  imaginary  pair  thus  indicated. 

[In  an  equation  of  degree  higher  than  the  third  degree,  it  ispott^le, 
when  the  first  member  of  it  has  a  quadratic  factor,  the  roots  of  which 
are  imaginary,  that  a  root  of  the  first  derived  equation  may  be  equal 
to  the  real  part  of  the  imaginary  pair  ;  but  this  can  happen  only  under 
peculiar  circumstances.  Let  Ff=0  be  an  equation  of  degree  higher 
than  the  third  degree,  and  of  which  /is  a  quadratic  factor,  such  that 
the  roots  of  /=0  are  imaginary.  Then,  writing  F\  /*,  for  the  fiist 
derivees  of  F/f  the  first  derivec  of  Ff  will  be 

Ff  +/P' ; 

and  if  this  be  zero,  for  the  value  of  4r,  which  is  the  root  of  the  simple 
equation/*  «0,  then  F^  must  be  zero  also  ;  since /is  not  zero  for  that 
value  of  X,  but  is  necessarily  a  positive  number.  Hence,  the  value  of 
Xf  which  satisfies  the  equation  /*  =  0,  cannot  possibly  also  satisfy  the 
derived  equation 

unless,  under  the  special  condition  that  s  is  a  root  of  jP  =  0,  as  weU  as 
arootof/»  =  0]. 

(12.)  The  conclusion  in  the  last  Article,  namely,  that  the  value  of 
X,  which  causes  Q  to  vanish  between  like  signs  of  P  and  P\  can  never 
be  equal  to  the  real  part  of  the  pair  of  imaginary  roots  indicated,  may 
be  easily  generalized;  and  the  more  comprehensive  proposition  be  stated 
thu  s ; 


Young — Algebraical  Equations  of  the  Third  Degree ^  Sfc:    37 

If  two  roots,  whether  real  or  imaginary,  of  a  cubic  equation  be  ex- 
pressed in  the  form  p-^q  (and  any  two  numbers  may  be  so  expressed),* 
it  is  impossible  that,  by  diminishing  the  three  roots,  each  by  p,  the 
resulting  equation  can  ever  be  of  the  form 

r'  +  ^^  +  Ox  +  ilo^O. 

For,  putting  a  for  the  diminished  third  root  of  the  equation,  the  three 
roots  of  the  transformed  equation  wiU  be 

a^q^q^ 

and,  therefore,  the  coefficient  of  a?,  in  that  transformed  equation,  will  be 

+  a^  -  <7j^  -  fl  J*  =  -  J* ; 

and,  consequently,  this  coefficient  cannot  be  zero,  so  long  as  g  is  a 
significant  quantity — whether  real  or  imaginary. 

[If  q  be  zero,  that  is,  if  the  cubic  equation  have  two  roots,  each 
equal  to  p,  then,  of  course,  not  only  is  the  coefficient  of  x,  in  the 
transformation  by  p  zero,  but  the  absolute  term  in  that  transformation 
is  also  zero]. 

(13.>  It  is  deserving  of  remark,  finally,  that— 

If  the  tame  pair  of  imaginary  roots  enter  into  two  different  equa- 
tions, that  pair  may  be  indicated,  by  the  signs  of  the  coefficients  of  one 
of  those  equations,  as  belonging  to  the  positive  region  of  the  roots,  and 
by  the  signs  of  the  coefficients  of  the  other  equation,  as  belonging  to 
the  negative  region. 

Tor,  first,  let  there  be  the  equation 

(j?'  +  a»Xj?  +  i)=aj'  +  6x*  +  ff4:«  +  a>&  =  0.  .  .  [1]; 

and,  next,  the  equation 

(a;'  +  a*)(«-<?)»a:*-C4^  +  a'i?-a»c=0  .  .  .  [2], 

in  which  equations  h  and  e  are  both  positive  numbers.  Then  the 
three  roots  of  [1]  will  all  belong  to  the  negative  region  of  the  roots, 
and  the  three  roots  of  [3]  will  all  belong  to  the  positive  region ;  and 
yet  the  pair  of  imaginary  roots,  namely,  the  two  roots  of  the  equation 

are  the  same  in  both  equations. 


•  For  r,  r',  being  any  two  numbers,  if  wo  put  p  for  Jr  -f  Jr',  aud  j  for  ^r  -  ^r', 
we  ihall  have  r  «/>  +  y,  and  »'  ^p  -  y. 


38  Proeeedinga  of  the  Boyal  Irish  A  eademy. 

Let  now  each  of  the  roots  of  the  equations  [  1  ]  and  [2]  be  diminished 
by  any  positive  number  5  ;  then  the  signs  of  the  terms  in  the  trans- 
formed equation  deduced  from  [IJ  will  all  be  positive;  but  in  the 
transformed  equation  deduced  from  [2]  it  is  plain  that  ^  may  be  suf- 
ficiently small  to  cause  the  signs  of  the  terms  to  be  alternately  positive 
and  negative,  as  in  the  equation  [2]  itself.  The  same  pair  of  ima- 
ginary roots  must,  however,  enter  into  both  of  the  transformed  equa- 
tions ;  though,  in  the  first  of  these,  the  signs  of  the  terms  imply  that 
the  imaginary  roots  belong  to  the  negative  region ;  and  in  the  second, 
the  signs  imply  that  these  same  roots  belong  to  the  positive  region. 

We  thus  see  that  the  region  in  which  a  pair  of  imaginary  roots  is 
indicated  by  the  signs  of  the  terms  of  an  equation,  supplies  no  suffi- 
cient clue  as  to  whether  the  real  part,  common  to  the  two  imaginary 
roots,  is  positive  or  negative,  whenever  the  equation  is  of  a  higher  de- 
gree than  the  second  degree.  In  a  quadratic  equation,  of  which  the 
roots  are  imaginary,  the  case  is  di^erent ;  the  sign  of  the  real  part  is 
always  indicated  ;  it  is  the  opposite  of  that  prefixed  to  the  coefficient 
of  the  middle  term,  whenever  such  middle  term  is  present.  If  the 
middle  term  be  absent,  the  real  part  of  each  imaginary  root  will  then, 
of  course,  be  zero ;  but  in  a  complete  quadratic  equation,  not  only  is 
the  region  to  which  each  of  the  two  roots  belongs  indicated — wheUier 
these  roots  be  real  or  imaginary — ^but  the  part  of  the  pair  of  roots  which 
is  free  from  the  radical  sign  is  also  indicated  ;  it  is  always  half  the  co- 
efficient of  the  middle  term,  taken  with  changed  sign — the  coefficient 
of  the  first  term  being  unity.  In  other  words,  as  before  stated,  the  part 
which  precedes  the  radical  sign  is  always  the  root  of  the  simple  equa- 
tion derived  from  the  quadratic,  whether  the  other  part  of  the  expres- 
sion for  the  pair  of  roots  of  the  quadratic  be  real  or  imaginary. 

In  the  foregoing  discussion,  I  have  frequently  spoken  of  a  pair  of 
imaginary  roots  as  being  in,  or  belonging  to,  the  positive  region,  or 
the  negative  region.  This  phraseology,  though  in  conformity  with 
general  usage,  is  objectionable.  An  imaginary  quantity  cannot  have 
any  place  in  a  series  of  positive  numbers,  nor  yet  in  a  series  of  nega- 
tive numbers ;  because  it  is  entirely  out  of  the  range  of  every  series  of 
numhen.  The  phrase  should  be  taken  to  mean  merely  that  the  indicator 
of  the  pair  is  in  the  positive,  or  in  the  negative  region,  as  the  case  may 
be ;  or,  still  more  explicitly,  that  the  indicator  is  a  positive  or  a  nega- 
tive numher.  We  have  seen  above  that  Uie  same  pair  of  imaginary 
roots  may  have  just  as  much  claim  to  a  place  in  a  series  of  negative 
numbers,  as  to  a  place  in  a  series  of  positive  numbers,  and  to  a  place 
in  a  series  of  positive  numbers,  as  to  a  place  in  a  series  of  negative 
numbers ;  and  this  is  the  same  as  saying  that  the  pair  itself  is  not  en- 
titled to  a  place  in  either  series :  it  is  the  indicator  only  of  that  pair, 
which  can  be  said,  in  strictness,  to  range  with  positive  or  with  negative 
numbers,  or  which  can  occupy  any  place  among  them. 

Taking  the  derived  functions  in  reverse  order,  commencing  with 
the  function  of  the  fiist  degree,  if  the  value  {i\)  of  Xy  which  causes 


YouNO — Algebraical  £quaiiotis  of  the  Third  Degree,  8fc.    39 

this  fanction  to  vanish,  causes  it  to  do  so  hetween  like  signs,  then  is 
Ti,  with  its  proper  sign,  the  indicator  of  a  pair  of  imaginary  roots  in 
the  contiguous  quadratic  function,  when  this  is  equated  to  zero.  If 
a  value  (r,)  of  re,  which  causes  this  quadratic  function  to  vanish,  canises 
it  to  vanish  hetween  like  signs,  then  is  rt,  with  its  proper  sign, 
the  indicator  of  a  pair  of  imaginary  roots  in  the  contiguous  function 
of  the  third  degree,  when  this  is  equated  to  zero,  and  so  on  ;  the 
sign  of  ri,  r„  &c.,  denoting  the  region  in  which  the  pair  of  imaginary 
roots  is— not  sittuUed,  hut  indicated.  And  what,  in  this  case  of  a  pair 
of  imaginary  roots,  is  the  indicator,  becomes,  in  the  case  of  a  pair  of 
unequal  real  iDots,  a  e^aratar  of  those  roots. 

A  pair  of  roots  indicated  in  any  interval  [a,  ft],  if  they  turn  out 
to  be  imaginary,  will  be  equally  indicated  in  the  indefinitely  narrow 
interval  [r-5,  r  •»-  ^],  be  5  ever  so  small,  r  being  the  indicator.  The 
modification  which  the  coefficients  of  that  quadratic  factor  of  the 
function  to  which  these  imaginary  roots  are  due  (in  order  that  the 
two  roots  indicated  between  the  above  narrow  limits  may  be  real 
roots,  the  other  roots  of  the  function  remaining  undisturbed)  must 
evidently  be  such  as  to  make  the  quadratic  factor  the  complete  square, 
{x-r)\* 

Of  course,  the  same  pair  of  equal  roots  (r,  r)  would  replace  the 
pair  of  imaginary  roots  by  making  a  suitable  modification  of  the  final 
term  of  the  function  alluded  to,  without  any  interference  with  the 
other  coefficients  ;  ymt,  then,  all  the  remaining  roots  of  the  function 
would  be  changed ;  since,  for  no  one  of  the  vidues  of  x^  for  which  the 
tmaliend  function  vanishes,  would  such  evanescence  take  place  when 
the  final  term,  or  the  absolute  number,  on/y,  was  changed. 


NOTE. 
On  th*  fommlA  [4],  in  Aztide  (S). 


The  general  ezpTesakm  [4],  for  the  three  roots  of  a  cnbio  equation,  is  entirely 
free  from  superfluous  Talues.  The  values  there  sjinbolised  are  just  thre$  in  num- 
ber, the  cube  root  being  the  only  item  in  the  formula  which  involves  multiple 
values.  The  symbol  r  represents  one  only  of  the  two  roots  of  the  quadratic  equa- 
tion Q*  —  ZFF*  =■  0 ;  which  one  of  the  two  is  entirely  matter  of  choice.  If  after  the 
root  selected  has  been  employed,  the  other  root  be  introduced  into  the  formula,  in  its 
place,  we  shall  get  a  second  expression  for  Xy  differing  from  the  fiT^t  one  only  in 
appearance ;  and,  symbolising  the  same  three  values,  tne  analytical  investigation  of 
the  formula  sufficicoUly  shows  such  to  be  the  case. 


*  The  quadratic  factor,  alluded  to  above,  is  that  which  enters  the  derived  equa- 
tion of  lowe$i  degree,  into  which  imaginarity  is  transmitted  from  the  primitive 
equation ;  the  quadratic  factor  spoken  of  belongs  Xoihit  primitive  equation  only  when 
the  imaginarity  so  enters  that  it  is  not  transmitted  to  a  derived  equation. 


40  Proceedings  of  the  Royal  Inah  Academy, 

y. — Ok  the  EauATiOK  of  the  Sqttabes  of  the  Diffebexcbs  of  a 
BiatTADRATic.  By  John  Caset,  LL.  D.,  M.  R.  I.  A,,  Professor  of 
Mathematics  in  the  Catholic  TJniyersity  of  Ireland. 

[Read  April  13th,  1874.] 

The  following  method  of  finding  the  equation  whose  roots  are  the 
squares  of  the  differences  of  the  roots  of  a  biquadratic  given  by  its 
general  equation,  with  binomial  coefficients,  has  been  in  my  possession 
for  some  years.  It  occurred  to  me,  while  reading  Professor  Roberts' 
solution  of  the  same  question,  published  in  Tortolini's  ''Annali  di 
Hatematica."  As  it  is,  I  believe,  shorter  and  more  elementary  than 
the  solutions  hitherto  published,  it  may  be  deserving  of  the  attention 
of  mathematicians. 

I.  Notation, 

Let  (a,  3,  (T,  d,  Sy^x,  1)*  =  0  be  the  quartic,  then  we  shall  denote 
^  -  ae,  the  discriminant  of 

(a,  h,  (?,  Jx,  l,yhy  H; 
a«rf  +  26'-3aJcby  G\ 

(?  is  evidently  «1  3-r,     when    A  is   the  discriminant  of  the  cubic 

(a,  3,  e,  d^  Ij^x,  ly,  and  the  vanishing  of  O  is  the  condition  that  the 
roots  of  this  cubic  may  be  in  arithmetical  progression  ;  we  shall  also 
denote  the  quadratic  invariant  of  the  quartic,  ae--  ibd  +  3^*  by  /„  and 
its  cubic  invariant  or  catalecticant 

ace  +  2bcd-'  ad*  -  tfi'  -  c*  by  /j  ; 

then,  since  (r,  H,  /,  I3  are  functions  of  the  differences  of  the  roots,  we 
have  at  once,  by  taking  a  =  1  and  &  »  0,  the  well-known  theorem 

G'=4JP-/,-/aJK  (I) 

II.    Euler^s  Medudng  Cubic. 

Let  the  quartic  (a,  i,  <?,  rf, «,  ^z^  I)*  =  0  be  deprived  of  its  second  term, 
and  it  becomes,  making  a  =  1, 

;c*-6J24?«  +  4(7i:+/,-3iP  =  0,  (2) 

and  Euler's  reducing  cubic  is 

y»-3^y'+3(ir'-j:|]y--^  =  0.  (3) 

This  becomes  by  changing  y  into  y  +  iT,  that  is,  by  taking  away  the 
second  term,  and  making  use  of  (1) 


Casey — On  the  Biquadratic.  41 

III.  Equation  of  D%fferenee$. 

If  iTi,  Xty  x^,  a?4,  be  the  roots  of  (2),  and  v^,  »,*,  v^  the  roots  of  (8),  we 
have  by  Euler's  solution, 

(^i  -  «i)'  -  4(V  +  r,»)  +  8r,t;,. 
Hence,  if  x  be  a  root  of  the  required  equation,  and  a^,  a,,  a,  the  roots 

of  (4)  

J  =  4  (oi  ^  a,  +  2H)  +  8  n/  (a,  +  J)(aj+  JST) 

.-.  {«  -  4  {«4  4  «,)  -  8^)«  =  64  {  fljOs+Ca,  +  a,)  J?+^j. 

Now,  by  equation  (4) 

flj  +  oj  =  -  ax  and  a^3  r=  -  -— . 

4ai 

Hence,  making  these  substitutions,  and  putting  y  for  a^,  we  get 

16/ 
(*  +  Ayy  -  16&  + 2=0.  (5) 

The  question  is  now  reduced  to  the  elimination  of  y  between  (4) 
and  (5),  which  is  easily  performed,  as  follows.    From  (4)  we  have 

and  eliminating  in  succession 

—  and  y'  from  (5)  and  (6), 

we  get  the  two  quadratics, 

48y»  -  8«y  -  («»  -  16JJ«  +  16/.)  =  0  (7) 

8«y»  +  («« -  16JE&  +  4/a)  y  +  12/,  =  0.  (8) 

Again,  eliminating  y*  from  (7)  and  (8)  we  get 

i'-16jy^*  +  16/a8-h72/a  . 

^"■'        14«»-96i/z  +  24/a       '  ^^ 

and  substituting  this  value  of  y  in  (7)  we  get  the  required  equation — 
*•  -  48  J&  +  8  (/,  +  96^y 

-  82  (32(?>  +  48/^2"+  45/sy 

-  18  (7/,*-  384/,ZP+  288/»£r)«» 

-  384  (6/2»JZ^+  4/,^+  &IJt)% 

+  256(/,'-27/,*)=0. 

In  the  preparation  of  this  Paper,  Professor  Ball's  Memoir  on  the 
Solution  of  the  Biquadratic,  published  in  Volume  vir.  of  the  **  Quarterly 
Journal  of  Pure  and  Applied  Mathematics,"  has  been  of  much  use  to  me. 

R.  I.  ▲.  VROC,  SBR.  11.,  VOL.  II.,  SCIENCE.  Q 


42 


Proceedingt  of  the  Royal  Irish  Academy, 


TI. — On  a  Spectboscope  of  the  Binocular  Form  for  the  Observation 
OP  Faint  Spectra.     3^y  Charles  E.  Bukton,  B.  A.,  F.  R.  A.  S. 

[Read  May  26,  1874.] 

The  instrument  described  in  this  notice  was  constructed  at  the  in- 
stance of  Mr.  Stoney,  out  of  a  grant  of  money*ontrusted  to  me  for  tlie 
purpose  by  the  Royal  Irish  Academy.  Owing  to  the  pressure  of  other 
business  upon  Mr.  Grubb  and  Mr.  Spencer,  on  whom  devolved  tlie 
carrying^  out  of  the  details  of  the  construction,  the  instrument  has 
only  come  into  my  hands  within  the  last  few  days,  and  its  capabilities 
must,  therefore,  be  considered  as  not  yet  fully  tested. 

The  binocular  form  was  adopted  at  Mr.  Stoney' s  suggestion,  in 
order  to  secure  that  great  increase  of  power  and  comfort  in  observa- 
tion of  faint  and  difficult  objects  which  results  from  the  co-operation  of 
both  eyes.  I  append  an  outline  sketch  of  the  spectroscope,  of  which 
the  following  is  a  description. 

The  same  parts  are  designated  by  the  same  letters  in  both  plan 
(Fig.  1.)  and  elevation  (Fig.  2.),  and  are  drawn  to  the  same  scale, 
namely,  one-sixth  of  full  size.  The  working  parts  are  sustained  and 
connected  by  a  mahogany  frame- work  B,  which  protects  the  internal 
arrangement,  and  gives  support  to  the  recording  table,  marked  Slider, 


Collimators.  The  collimators  C  C\  which  carry  the  slit  S  are 
fixed  upon  a  mahogany  base-board,  movable  in  a  vertical  plane  about 
the  axis  a  a\  and  capable  of  being  fixed  at  any  required  inclination 
to  the  line  hhhj  means  of  a  binding  screw  *,  which  passes  through'  a 
circular  slot  in  B  into  the  wooden  base-piece. 

27ie  Prisma,  F  and  F'  are  the  prisms,  worked  as  nearly  as  possible 
to  the  same  form.  The  three  faces  of  each  prism  are  polished,  so  that 
any  one  of  the  three  angles  may  be  employed  to  form  a  spectrum. 
In  each  prism  the  three  angles  are  not  equal,  but  subtend  respectively 
68®,  60°,  and  62°.  The  range  of  dispersion  obtainable  with  a  single 
prism  is,  therefore,  very  considerable,  if  the  three  angles  are  made 
use  of  in  succession. 


BtJKTON — On  a  Spectroscope  of  the  Binocular  Form.        43 

This  property  of  each  prism  is  made  available  by  mounting  it  on 
a  circular  wooden  disc,  centrally  perforated  to  admit  a  binding  screw, 


hi 


Fig.  2. 


which  secures  it  to  the  inner  side  of  B^  and  when  tightened  prevents 
the  disc  from  rotating.  The  discs  and  binding  screws  attached  to  the 
prisms  are  shown  at  t  t'y  N  N\ 

The  observer  can  readily  turn  round  the  wooden  disc  with  the 
attached  prism,  after  slackening  Ny  and  he  can  fix  the  prism  again  in  any 
position  he  pleases  by  once  more  tightening  N,  The  two  prisms  are 
perfectly  independent  of  one  another. 

Telescopes,  The  telescopes  T  T  are  fixed,  like  the  collimators,  to 
a  single  mahogany  base-board,  and  move  also  in  a  vertical  plane  about 
the  axis  of  the  spindle  c^"  a"  which  moves  with  the  base- board.  One 
extremity  of  this  axis,  that  marked  a'^  is  enlarged  for  the  reception 
of  the  clamp  of  the  recording  apparatus,  to  be  mentioned  presently. 
The  adapters,  carrying  the  eye-pieces,  are  connected  together  by  a  pair 
of  cross  bars  i,  h\  which  are  secured  to  them  by  screws  passing 
through  the  slots  in  the  outer  tubes  shown  in  the  plan, 

Focttssing  of  eye-pieces.  The  focussing  movement  is  communicated 
to  the  eye-pieces  simultaneously  as  follows.  A  piece  of  flat  linked 
chain,  c,  is  fastened  at  one  extremity  to  the  crossbar  nearest  the  object 
glasses,  passed  twice  round  the  spindle  JFJ  which  is  fixed  to  the 
wooden  base  plate,  and  secured  by  a  clip  arrangement  to  the  cross 
bar  above  the  eye- pieces.  On  turning  Wy  the  chain  is  wound  one 
way  or  the  other,  and  the  adapters  move  with  it. 

Each  of  the  eye- pieces  has  an  independent  sliding  motion  in  its 
own  adapter.  In  the  focus  of  each  eye-lens  is  a  pointer,  of  a  wedge 
form,  borne  by  a  split  tube,  fitting  moderately  tight  into  the  eye-piece 
adapter.  These  pointers  are  capable  of  adjustment  in  every  direc- 
tion. 


44  Proceedings  of  the  Royal  Irish  Academy. 

Recording  apparatus.  The  recording  apparatus  is  a  modification  of 
that  devised  some  years  since  by  Mr.  Grubb,  and  found  by  those 
who  have  employed  it  to  combine  a  very  considerable  amount  of 
accuracy  with  great  facility  in  use,  dispensing  also  with  the  necessity 
for  a  reading  lamp  at  the  time  of  observation,  and  thereby  preventing 
that  loss  of  time  which  is  inevitable  if  micrometric  apparatus  of  the 
ordinary  construction  be  employed  for  the  measurement  of  extremely 
faint  spectra. 

The  bar  m  (Fig.  1.)  is  thickened  and  split  at  one  extremity  to 
receive  the  end  a"  of  the  axis  on  which  the  base-board  carrying  the 
telescopes  moves. 

The  two  prongs  of  the  fork  thus  formed  can  be  brought  together 
80  as  to  grip  a'*  tightly,  by  means  of  a  small  capstan-headed  screw. 

The  link  n  connects  the  free  end  of  m  with  the  recording  arm  ». 
The  two  ends  of  n  are  perforated  with  square  holes,  the  diagonals  of  the 
squares  being  longitudinal  and  transverse  to  the  link. 

Through  these  square  holes  pass  screws  into  m  and  »,  in  which 
they  are  fixed.  Owing  to  the  position  of  the  holes,  these  pins 
work  practically  in  V  bearings,  and  steadiness  of  movement  is  thereby 
secured. 

f  moves  on  a  fulcrum  at  /,  and  carries  near  its  free  extremity  a 
pin  p,  directed  inwards  towards  the  slider.  By  pressing  the  finger 
gently  on  the  outer  side  of  the  arm  t  near  the  end,  a  dot  may  be  made 
on  a  card,  and  a  record  thereby  made  of  the  position  of  the  arm  at  the 
time.  The  slider  moves  in  either  direction  readily,  parallel  to  the 
line  hh.  If  m  bo  changed  to  a ',  and  the  telescopes  be  raised,  m  will 
be  constrained  to  rise  also,  and  by  means  of  the  link  n  will  raise  i 
and  p  with  it. 

Since  the  distance  from  the  object  glass  of  the  telescope  to  the 
final  image  is  9  in.,  m  being  4  in.  long,  nf\\  in.,  and  fp  15  in., 
any  motion  of  the  pointer,  if  small,  will  be  multiplied  at  p  by  the 
improper  fraction 

=  4'4 ; 

9  X  1*5 

an  amplification  which  is  found  to  be  practically  sufficient. 

The  slit  is  formed  of  two  long  long  brass  rules,  jointed  together 
in  exactly  the  same  manner  as  for  a  parallel  ruler. 

The  links  are  perforated  at  their  centres  for  two  screws,  one  for 
each,  on  which  they  severally  turn.  To  each  extremity  of  the  lower 
rule  is  fastened  one  end  of  a  piece  of  flat  linked  chain,  the  central 
portion  of  the  chain  being  coiled  twice  about  a  spindle,  on  which  is 
fixed  a  lever  about  6  inches  in  length. 

By  altering  the  position  of  this  lever,  the  chain  is  drawn  one  way 
or  the  other,  and  causes  the  rules  to  move. 

As  the  axes  on  which  the  links  turn  are  situated  in  the  centre  of 
their  length,  the  approach  of  the  jaws  of  the  slit  to  a  line  between 


Baily — On  Fossil  Plants  of  JSiltorcan,  45 

them  will  be  the  same  for  each  of  them,  and  the  desired  fixity  of  the 
centre  of  the  slit  opening,  and  therefore  of  the  spectral  lines,  with  re- 
spect to  the  pointer,  is  thereby  secured. 

It  is  hoped  that  this  instrument  may  be  useful  in  the  study  of  the 
spectra  of  the  Aurora  and  Zodiacal  Light,  which  are  not  yet  thoroughly 
known  ;  the  first  on  account  of  its  caprscious  variableness,  the  latter 
by  reason  of  its  extreme  faintness.  The  last-mentioned  difficulty, 
it  is  hoped,  may  be  overcome,  by  the  use  of  this  special  instrument, 
which  brings  both  the  eyes  into  use,  and  by  the  improvement  of  an 
opportunity  which  now  offers  for  the  study  of  the  Zodiacal  Light 
imder  favourable  circumstances,  as  regards  climate,  in  the  Mauritius. 

In  conclusion,  I  have  to  thank  Messrs.  Stoney,  Grubb,  and  Spencer 
for  numerous  suggestions  and  improvements  in  the  design  of  the  in- 
strument, and  to  apologise  for  the  unavoidable  haste  with  which  this 
notice  has  been  drawn  up,  previously  to  my  departure  to  Kodriguez  as 
one  of  the  expedition  to  observe  there  the  transit  of  Venus. 


VII. — On  Fosbilb  yaoif  the  Upper  Old  Red  Sandstone  op  Kil- 
TORCAN  Hill,  in  the  Codntt  of  KiLKENNr.  Report  No.  1.  By 
Wm.  Hellikr  Bailt,  F.  G.  S.,  &c. 

[Read  February  9,  1874.] 

Great  interest  in  the  fossil  plants  of  Kiltorcan  has  been  shown  by 
eminent  scientific  men,  especially  those  of  foreign  countries,  who  have 
made  fossil  botany  their  study ;  and  among  those  latter,  with  whom  I 
have  corresponded  on  the  subject,  I  may  mention  Professor  Geinitz,  of 
Dresden ;  Dr.  Schimper,  of  Strasbourg ;  Professor  Heer,  of  Zurich ; 
Principal  Dawson,  of  Canada  ;  Professor  De  Koninck,  of  Liege ;  and 
M.  Crepan,  of  Brussels—  all  of  whom  testify  in  their  communications 
to  the  scientific  importance  of  investigating  the  subject. 

Additional  interest  arises  not  only  from  the  perfect  state  of  preser- 
vation in  which  these  fossils  occur,  but  from  the  fact  that  they,  with 
their  associated  fossil  fauna,  assist  in  a  material  way  to  determine  the 
fresh  water,  or  marine  origin,  of  the  great  mass  of  old  red  sandstone 
strata  developed  in  the  British  Islands,  as  well  as  on  the  continent  of 
Europe. 

Although  this  report  relates  more  especially  to  the  fossil  plants,  it 
will  not  perhaps  be  thought  irrelevant  to  allude  to  the  associated  animal 
remains  of  mollusca,  Crustacea,  and  fish  discovered  at  the  same  place. 

The  quarry  from  which  the  specimens  now  exhibited  were  collected, 
in  consequence  of  its  remote  situation,  has  not  been  much  excavated, 
except  for  scientific  purposes ;  it  is  situated  between  Kilkenny  and 
Waterford,  near  the  Ballyhale  railway  station,  on  an  elevated  ridge 


/    46  Proceedings  of  the  Royal  Irish  Academy, 

of  Old  Red  Sandstone  T" yellow  sandstone"  of  Sir  Richard  Griffith), 
whioh  rises  gradually  from  beneath  the  limestone  plain  to  heights  of 
400  or  500  feet,  and  in  some  places,  as  near  Jerpoint,  to  as  much  as 
800  feet  above  the  sea  leveL 

The  beds  of  fine  grained  greenish  sandstone  dip  at  a  very  slight 
angle,  and  separate  easily  into  slabs  of  large  size,  some  of  them  being 
covered  by  plant  remains ;  the  surfaces  of  these  slabs  are  sometimes 
stained  quite  black,  probably  with  manganese  or  iron,  and  are  very 
disappointing  when  found  in  this  state.  The  most  frequent  plant  is 
Palkopteris  Hihernieus ;  first  noticed  by  the  late  Professor  Edward 
Forbes  at  the  Belfast  meeting  of  the  British  Association  in  1853,  under 
the  provisional  name  of  Cyclopteris,  afterwards  referred  to  Adiantites 
by  M.  Adolphe  Brongniart,  and  now  placed  by  Professor  Schimper  in 
his  genus  Palaeopteris — that  eminent  authority,  in  his  valuable  work, 
•*  Traite  de  Pal^ontologie  V6getale,"  stating  that  it  differs  from  Cy- 
clopteris in  the  arrangement  of  its  leaflets,  and  from  Adiantites  in  its 
mode  of  fructification. 

Magnificent  fronds  of  this,  the  most  ancient  fern,  are  impressed  upon 
the  slabs  with  remarkable  distinctness,  so  much  so  that  even  the  vena- 
tion  on  the  leaflets  is  clearly  discernible.  Some  of  these  fronds  are 
between  four  and  five  feet  long  and  three  feet  broad.  The  peculiar 
.mode  of  fructification  by  a  transformation  of  sterile  into  fertile  pinnules 
is  well  shown  in  some  specimens,  and  so  also  is  the  basal  portion  of 
the  frond.  Two  additional  species  of  fossil  ferns  have  been  described 
by  me  from  this  place  under  the  names  of  Sphenopteris  Hookeri  and 
S.  Humphresianum^  both  of  which  are  comparatively  rare. 

Another  plant,  frequent  at  Kiltorcan,  having  a  fluted  or  ribbed 
stem,. its  upper  portion  branching,  I  formerly  considered  to  be  identical 
with  Sagenaria  Velthieniiana,  Professor  Schimper,  however,  who  had 
frequent  opportunities  of  comparing  its  fruit  with  that  of  8.  Velthiemiana, 
assures  me  that  it  differs  greatly  from  that  species ;  believing  it  to  be 
an  undescribed  plant,  he  has  named  it  Sagenaria  Bailyana,  The  central 
axis  of  this  plant  is  seen  in  some  specimens,  indicating  its  loose  texture 
and  its  alliance  to  Sigillaria. 

A  fine  example  of  this  plant  .was  discovered  by  me  and  Mr.  Alex. 
M'Henry,  who  assisted  me  in  these  explorations.  After  excavating  to 
a  depth  of  about  four  feet,  we  uncovered  a  portion  of  the  stem  and 
traced  it  out  as  far  as  possible ;  it  rested  on  the  surface  of  a  bed  which 
was  much  jointed,  consequently  it  was  not  possible  to  preserve  it 
entire.  Careful  sketches  and  exact  measurements  were  however  made 
by  me  on  the  spot.  Unfortunately  we  could  not  get  at  the  termination 
to  see  if  the  stigmaria-like  roots  were  attached ;  this  must  remain  a 
problem  until  further  excavations  can  be  made. 

The  total  length  of  this  specimen  was  20  feet  4  inches,  the  stem  at 
its  lowest  portion  being  six  inches  in  diameter.  It  commenced  to 
branch  at  15  feet  from  the  visible  termination ;  after  the  first  division 
the  branches  are  one  and  a  half  inches  broad,  continuing  to  diminish 
until  they  became  reduced  to  a  quarter  of  an  inch  in  breadth. 


Baily — On  Fossil  Plants  of  Kiltorcan.  47 

The  upper  portion  of  its  branches  corresponds  with  CycloHigma  or 
Lepidodendron  minuta  of  Dr.  Haughton. 

A  central  axis  traverses  the  whole  of  the  plant,  composed  of  soft 
tissue,  with  an  open  cellular  structure,  as  in  Sigillaria  and  Stigmaria. 

"What  I  believe  to  be  the  roots  and  rootlets  of  this  species  permeate 
certain  beds  beneath,  just  as  Stigmaria  does  the  clay  immediately  under 
the  coaL 

Cone-like  bodies  are  frequent  in  the  same  bed ;  they  somewhat  re- 
semble Lepidostrobus  of  the  coal  strata,  and  are  composed  of  elongated 
scales,  terminating  in  long  linear  processes ;  these  scales  show  large 
and  very  distinct  sporules.  They  are  evidently  the  fruit  of  a  Lycopod, 
but  have  never  yet  been  found  attached  to  the  Sagenaria,  to  which  it 
is  presumed  they  belonged. 

A  third  description  of  plant,  extremely  abuniiant  at  this  place,  has 
been  described  by  Dr.  Haughton  under  the  name  of  Cyclostigma. 
They  usually  occur  in  a  fragmentary  state,  and  are  much  compressed. 
One  of  the  most  important  additions  to  our  knowledge  of  these 
plants  is  a  specimen  in  the  collection  now  obtained ;  this  I  believe  to 
be  a  young  example  of  Cydostigma  Kiltorkeiue.  It  was  found  in  a  layer 
with  Palaopteru  Hihemicua^  about  two  and  a  half  feet  below  the 
commencement  of  the  rock ;  it  shows  what  has  never  been  met  with 
before,  the  rounded  base,  with  attached  rootlets.  The  total  length  of 
this  specimen  is  two  feet  three  inches,  its  greatest  diameter  being  one 
inch  and  one-eighth.  The  widely  distant  stigmee,  absence  of  longitu- 
dinal rib-like  markings,  and  different  character  of  root,  distinguish  it 
essentially  from  the  Sagenaria,  or  from  Knorria  Bailyana,  with  which 
some  Palseophy  tologists  have  sought  to  identify  it.  This  plant  appears 
to  have  been  less  cylindrical  than  the  Sagenaria.  I  am  inclined  to 
believe  that  the  fine  specimen  in  the  collection  of  the  Royal  Dublin 
Society,  named  by  M.  Adolphe  Brongniart  Lepidodendron  Griffithsiij  is 
the  terminal  portion  of  this  species.  In  the  collection  made  by  the 
Geological  Survey,  also  from  this  place,  there  is  a  similar  portion, 
showing  the  blunt  brush-like  apex,  the  stigmee  becoming  more  closely 
arranged  towards  the  top,  and  the  rigid  linear  leaves,  three  or  four 
inches  long,  spreading  out  on  each  side  at  regularly  decreasing  intervals 
from  a  half  to  the  eighth  of  an  inch. 

The  associated  animal  remains  are,  of  mollusca,  one  example  only, 
the  large  bivalve  shell  named  by  Professor  Forbes  Anodonta  Jtikem. 
Its  close  resemblance  to  the  recent  Anodonta  cygncem^  the  large  fresh- 
water muscle,  common  in  some  of  our  lakes  and  rivers,  sufficiently 
justifies  its  generic  alliance,  and  assists  materially  in  proving  the  fresh- 
water origin  of  the  deposit. 

Several  species  of  Crustacea  have  from  time  to  time  been  added  to 
the  list  of  fossils  foimd  at  this  place.  The  late  Mr.  Salter  first  indi- 
cated the  probable  existence  of  Eurypterus  from  a  very  fragmentary 
specimen ;  this  indication  I  have  been  enabled  to  confirm  by  the  dis- 
covery of  better  specimens,  and  have  named  a  species  Pterygotut 
Sihemtcui,     This  Mr.  "Woodward  has  since  referred  to  Eurypterus. 


48  Proceedings  of  the  Royal  Irish  Acadetny. 

In  addition  to  this,  we  collected  a  Limuloid  form,  which  I  have 
called  Belinurus  Kiltorkensis,  and  a  Phyllopod,  Praraearis  MacHenrici, 

The  fish  remains  are  also  of  considerable  interest,  and  are  eminently 
characteristic  of  Old  Red  Sandstone  strata.  They  consist  for  the  most 
part  of  detached  portioi\9,  comprising  a  few  conical  teeth,  resembling 
those  of  Dendrodus  or  Bothriolepis,  jaws  with  teeth  most  probably 
belonging  to  Coccosteas,  and  osseous  plates  of  the  same  fish,  these  being 
the  most  numerous.  A  small  species  of  Pterichthys  also  occurs,  and 
numerous  scales  of  Glyptolepis.  Only  in  one  instance  were  we  suc- 
cessful in  obtaining  anything  like  an  entire  fish ;  it  belongs  to  the  last- 
named  genus,  and  I  believe  it  to  be  identical  with  Glyptolepis 
elegans. 

The  great  importance  of  the  fossils  of  this  locality  cannot,  I  feel 
convinced,  be  overrated,  and  it  will  doubtless  yield  still  more  valuable 
results.  Duplicate  sets  of  these  fossils  have  already  been  supplied  to 
various  scientific  institutions  both  in  our  own  country,  on  the  Conti- 
nent, and  in  America.  The  letters  received  in  acknowledgment  suffi- 
ciently testify  as  to  the  appreciation  in  which  they  are  held. 

Professor  Oswald  Heer,  in  a  paper  read  before  the  Geological 
Society  of  London  on  the  Carboniferous  flora  of  Bear  Island  (lat. 
74°  30'),  enumerates  18  species  of  plants,  indicating,  according  to  the 
author,  a  close  approximation  of  the  flora  to  that  of  Tallow  Bridge  and 
Kiltorcan ;  also  to  the  Qrey  wacke  of  the  Yosges  and  the  southern  Black 
Forest,  and  the  Yemeuiler  shales  of  Aix,  and  St.  John's,  New  Bruns- 
wick. He  refers  this  flora  to  the  Lower  Carboniferous,  and  therefore 
argues  that  the  line  of  separation  between  the  Carboniferous  and  Devo- 
nian must  be  drawn  below  the  yellow  sandstone.  The  prevalence  of 
fishes  of  Old  E«d  Sandstone  type  in  the  overlying  slates  he  regards  as 
an  argument  to  invalidate  the  conclusion. 

Sir  Charles  Lyell,  in  the  discussion  which  followed,  remarked  that 
the  yellow  sandstone  of  Dura  Den  in  Fife,  and  of  the  counties  of  Cork 
and  Kilkenny  in  Ireland,  contain  fish  exclusively  Devonian,  and  others, 
such  as  the  genus  Coccosteus,  which  are  abundantly  represented  in  the 
Middle  Old  Red  Sandstone,  and  by  one  species  only  in  the  Carboniferous 
formation.  The  evidence  derived  from  these  fish  inclined  him,  there- 
fore, to  the  belief  that  the  yellow  sandstone,  whether  in  Ireland  or 
Fife,  should  be  referred  to  the  Upper  Devonian  and  not  to  the  Lower 
Carboniferous. 


VIII. — ^NOTES   OK  THE  MtOLOQT  OF  THE  CoATl-MONDI   (NaSUA  NaKICA 

AND  N.  Ftjsca)  Aim  CoMMoir  Mabtiw  (MiKTEs  Foina).    By  H.  W. 
Mackintosh,  B.A. 

[Bead  April  13,  1874.] 

The  following  remarks  are  founded  on  the  dissection  of  one  Bpecimen  of 
Nasua  narica,  one  of  N,  fusca^  and  two  of  Martesfoina.  They  all  formed 
part  of  the  collection  in  the  Dublin  Zoological  Gardens,   and  having 


Mackintosh — Notes  on  the  Myology  of  the  Coati-Mondi^  8fc,    49 

died  during  the  summer  of  1873,  were  forwarded  for  examination  to 
Professor  Macalister,  who  kindly  gave  me  the  opportunity  of  assisting 
him  in  dissecting  them. 

We  noticed  the  following  points  of  general  anatomy : — 

There  was  no  recessus  pharyngeus,  a  rudimental  hursa  pharyngci, 
small  Eustachian  tuhes,  and  black  lymphatic  glands  in  N,  narica  ;  in  N. 
fwca  the  platysma  is  very  strong,  running  upwards  and  inwards  to 
the  middle  line ;  Maries  foina  resembles  N,  narica  in  having  black  lymph 
glands. 

The  facial  muscles  in  N,  narica  are; — 

Orbicularis  palpebrarum  simple,  arising  from  the  definite  ocular 
tendon;  levator  labii  superioris  large,  arising  from  the  maxilla  in  front 
of  the  orbit  and  running  downwards  and  forwards  to  be  inserted  ten- 
dinously  into  the  upper  lip  ;  levator  alse  nasi,  a  very  large  muscle  aris- 
ing just  above  the  infra-orbital  foramen,  and  running  forwards  under- 
neath the  last-named  muscle  to  be  inserted  by  an  expanding  tendon 
into  the  dermis  of  the  end  of  the  elongated  snout,  which  it  elevates 
and  lateralises ;  its  tendon  is  slightly  united  to  levator  labii  superioris, 
and  the  large  infra-orbital  nerve  runs  parallel  to  and  underneath  it ; 
levator  anguli  oris  consists  of  vertical  fibres  attached  underneath  tl)e 
eye ;  depressor  alse  nasi,  from  the  alveolus  vertically  upwards  to  the 
sides  of  the  alar  cartilage ;  retrahens  aurera,  very  large,  with  a  detach(  d 
slip  from  the  fascia  of  the  middle  line  of  the  neck ;  transversus  auri- 
culse  is  also  large,  and  atrahens  aurem  is  a  strong  round  bundle  of 
fibres  from  the  zygoma.     The  tongue,  has  the  usual  muscles. 

In  N.fuaea  levator  alse  nasi  and  levator  labii  superioris  form  a  single 
muscle ;  retractor  nasi  is  enormously  developed ;  there  is  a  double  retra- 
hens aurem,  a  single  zygomaticus ;  mandibulo-auricularis  is  strong ; 
there  is  a  transversus  depressor  amis,  and  a  normal  masseter. 

The  muscles  of  the  head  and  trunk  in  N.  narica  are ; — 

Bectus  capitis  anticus  major  arising  from  the  five  upper  cervical 
vertebrse,  and  inserted  directly  into  the  bulla  tympani ;  rectus  capitis 
anticus  minor  is  very  small,  arising  from  the  atlas,  and  inserted  as 
usual ;  digastric,  arising  from  the  post-tympanic  and  paroccipital  pro- 
cesses, covers  the  bulla  tympani,  has  an  inscription  (which  is  long  in 
N.fnsea),  and  is  inserted  into  the  posterior  third  of  the  mandibular 
ramus.  The  parts  of  longus  colli  are  not  separable.  Scalenus  anticus 
is  small  and  normal ;  scalenus  posticus  extends  from  the  four  lower 
cervical  transverse  processes  to  the  eight  upper  ribs.  The  sternohyoid, 
sternothyroid,  thyrohyoid,  and  cricothyroid  are  as  usual.  In  N.  fusca^ 
stemocostalis  arises  from  the  two  upper  stemebers  and  is  inserted  into 
the  first  rib;  the  brachial  artery  overlies  and  the  brachial  nerve 
underlies  the  supracondyloid  foramen ;  the  muscles  of  the  back  of  the 
neck  are  of  the  ordinary  carnivore  type ;  scalenus  posticus  runs  from 
the  third  cervical  vertebra  to  the  second,  third,  fourth,  fifth,  and  sixth 
ribs ;  scalenus  medius  extends  from  the  sixth  cervical  vertebra  to  the 
first  rib.     None  of  these  muscles  Avere  examined  in  the  Martin. 

R.  T.  A.  PROC,  BElt.   II.,  VOL.  II.,  8C1BNCE.  II 


50  Proceedings  of  the  Royal  Irish  Academy, 

In  the  fore  limbs : — 

Trapezius  consists  in  all  of  three  parts,  clavicularis  ('08*),  scapu- 
laris  superior  ('07),  and  scapularis  inferior  ('05) ;  the  first  of  these  arises 
from  the  occiput  in  the  coatis,  and  from  the  spine  of  the  axis  as  well 
in  the  martins,  and  is  inserted  into  the  rudimentary  clavicle  in  N,  narica 
and  Martes ;  in  JV.  fusea  it  joins  deidomastoid  at  its  insertion  into  the 
clavicle,  is  united  to  brachialis  anticus,  and  sends  a  slip  to  the  humerus ; 
the  superior  portion  of  scapular  trapezius  arises  from  the  spines  of  all 
the  cervicals  except  the  atlas  and  from  those  of  the  ten  upper  dorsals  ; 
it  has  the  usual  insertion  into  the  scapular  spine,  quite  separate  from 
the  inferior  division ;  in  N.  narica  it  is  united  at  its  origin  to  the  clavi- 
cular trapezius,  but  separated  at  its  insertion  by  trachelo-acromial. 
Trapezius  scapularis  inferior  varies  somewhat  in  position  in  all.  In 
N.  narica  it  arises  from  the  third,  fourth,  fifth,  and  sixth  dorsals,  and 
is  inserted  into  the  posterior  edge  of  the  scapula ;  in  N.  fusea  the  origin 
is  from  the  six  upper  dorsals,  and  the  insertion  is  into  the  root  of  the 
scapular  spine ;  finally,  in  Martes  it  arises  from  the  second,  third, 
fourth,  fifth,  sixth,  and  seventh  dorsals,  and  is  inserted  into  the  lower 
border  of  the  posterior  half  of  the  scapular  spine. 

Stemomastoid  ('08)  arises  from  the  presternum  in  all,  is  inserted 
into  the  paroccipital  process  in  N.  fusea,  and  into  theparamastoidin  the 
other  three ;  the  two  sternomastoids  are  mesially  connivent  in  the 
.  martins.  Cleidomastoid  ('04)  extends  from  the  paroccipital  to  the 
clavicle  in  iT.  fusea,  and  from  the  paramastoid  to  the  same  place  in  iT. 
.  narica  and  the  martins.  Omohyoid  was  absent  in  the  coatis  and  ex- 
ceedingly slender  in  Martes.  Trachelo-acromial  (-05)  presents  nothing 
of  importance. 

Rhomboid  ('07)  is  indivisible  in  Nasua  and  arises  from  the  occiput, 
all  the  cervicats,  and  the  five  upper  dorsals ;  the  insertion  is  as  usual. 
In  Martes  the  occipital  is  distinct  from  the  major  portion  at  its  origin, 
which  is  very  far  out  on  the  occiput ;  the  latter  part  arises  from  the 
six  lower  cervicals  and  from  the  two  upper  dorsals,  and  is  inserted 
into  the  scapular  spine  along  with  the  occipital  segment  Teres  major 
('08)  is  united  at  its  insertion  with  the  latissimus  dorsi  in  the  coatis, 
but  separate  from  it  in  Martes.  Teres  minor  ('01)  is  small  but  distinct 
in  all,  with  a  long  tendon  of  origin  and  insertion  in  N.  narica;  it  is  in- 
serted behind  and  above  scapular  deltoid  in  iV.  fusea, 

Latissimus  dorsi  ('23)  arises  from  the  dorsal  spines  (from  the  sixth 
to  the  tenth  in  iV.  nariea,  from  the  eighth  downwards  in  N,fusea^  and 
from  the  third  downwards  in  Martes),  from  the  three  lower  ribs  and 
from  the  lumbar  fascia,  and  has  the  usual  humeral  insertion.  Fectoralis 
minor  was  absent  in  all.  Fectoralis  major  (-30)  has  a  presternohumeral 
slip  in  all ;  the  rest  of  the  muscle  (bilaminar  in  N.  nariea,  unilaminar  in 
Martes)*arise8  from  the  whole  length  of  the  sternum,  and  is  inserted  into 


*  The  Nnmbors  refer  to  the  weights  in  N,  narica  in  decimals  of  an  ounce  avoir. 


Mackintosh — Notes  on  the  Myology  of  the  Coati-Mondi^  Sfc.    61 

the  humenis  as  usual.  In  N.fuBca  it  consists  of  three  parts — one  extend- 
ing from  the  entire  sternum  to  the  pectoral  ridge  of  the  humerus,  a  second 
going  from  the  six  anterior  mesostemal  stemehne  to  the  greater 
tuherosity  of  the  humerus  and  tendon  of  supraspinatus,  and  the  third 
arising  from  the  abdominal  parietes,  inserted  below  the  last,  and  united 
with  pectoral  quartus.  Peotoralis  quartus  ('14)  arises  from  the  carti- 
lages of  the  lower  ribs  and  from  the  fascia  over  them,  and  is  inserted  in 
the  axilla  in  close  contiguity  with  latissimus  dorsi  (and  pectoralis  major 
in  Martes). 

Subclayius  was  absent  in  all,  unless  represented  by  the  prester- 
nohumeral  slip  of  pectoralis  major,  which  is  very  constant  in  carni- 
vora.  Coracobrachialis  was  very  small,  and  represented  only  by  the  short 
variety  in  the  coatis;  but  in  the  martins  both  longus  and  brevis  existed, 
arising  by  a  common  tendon  from  the  coracoid  process ;  the  former  was 
inserted  by  a  tendinous  sling  extending  from  the  latissimus  dorsi  tendon 
to  the  lower  third  of  the  humerus,  and  the  latter  into  the  same  bone, 
aboTe  latissimus  and  separate  from  it. 

Deltoid  consists  of  three  parts,  clavicular  ('07),  scapular  ('04),  and 
acromial  ('03),  as  usual.  The  fii^t  of  these  is  only  remarkable  for  its 
very  low  humeral  insertion  in  iV.  nartea  ;  the  second  arises  in  N.  fiuca 
from  the  fascia  along  the  inferior  border  of  the  infraspinous  fossa,  and 
in  Martes  from  the  outer  half  of  the  scapular  spine ;  the  third  has  some 
of  its  fibres  continuous  with  those  of  brachialis  anticus,  and  shows  a 
distinct  inscription  at  the  point  of  junction  of  the  two,  in  N,  nartea. 
Supraspinatus  (-10)  and  infraspinatus  (-9)  are  normal  in  all,  the  former 
being  the  larger.  Subscapularis  is  also  normal,  and  has  respectively 
three,  four,  and  five  tendinous  planes  in  N.  narica^  Martes,  and  N.fwca. 
There  was  no  separate  pre-scapular  slip  in  the  first  two,  but  in  N.fusca 
it  was  quite  distinct,  passing  down  over  the  tendon  of  the  rest  of 
the  muscle. 

Serratus  magnus  ('16)  arises  from  eight  ribs  and  six  cervical  trans- 
verse processes  in  N,  narica,  from  nine  ribs  in  iV.  fusea,  and  from  seven 
ribs  and  five  cervical  transverse  processes  in  Martes,  and  is  inserted  as 
usual.  The  cervical  origin  was  not  recorded  in  If.  fusca,  Serratus 
posticus  superior  arises  from  the  fascia  of  the  back,  and  is  inserted  into 
the  third,  fourth,  'fifth,  sixth,  seventh,  eighth,  cmd  ninth  ribs  in  If. 
narica,  and  into  the  fifth  to  the  fifteenth  in  iV.  fusca.  Serratus  posticus 
inferior  is  inserted  into  the  three  lower  ribs  in  If,  narica. 

Biceps  (*06)  is  glenoradial  in  its  attachments  as  usual.  Brachialis 
anticus  (06)  arises  from  the  whole  of  the  external  aspect  of  the  hu- 
merus, and  is  inserted  into  the  ulna.  Triceps  longus  (*10)  not  very 
separate  from  extemus  in  the  coatis,  though  perfectly  so  in  Martes,  has 
two  heads  in  If.  narica — one  from  the  edge  of  the  glenoid  cavity,  and  the 
other  from  the  axillary  border  of  the  scapula ;  the  insertion  is  ole- 
cranal  as  usual ;  it  is  fused  with  triceps  extemus  in  the  N.fwca,  Triceps 
intemus  and  extemus  (-10)  are  fused  in  N.  narica,  but  moderately 
separate  from  one  another  in  the  other  animals ;  extemus  is  the  larger 
of  the  two  in  Martes.   Dorsi-epitrochlearis  ('05)  arises  in  If.  narica  from 


52  Proceedings  of  the  Royal  Irish  Academy. 

latibsimus  dorsi  and  by  an  inscription  from  tores  major,  and  from  the 
former  of  these  two  muscles  alone,  in  N.fusca  and  Martes,  it  is  inserted 
as  usual  into  the  olecranon.  The  anconei  are  united  to  biceps  in  N. 
narica;  anconeus  intemns  arises  from  the  supracondyloid  process  in 

JV.  fu8C(k 

Pronator  radii  teres  (-03)  arises  from  the  usual  place  in  all,  but 
presents  a  slightly  different  insertion  in  each ;  in  N",  narica  it  is  inserted 
into  the  lower  three-fourths  of  the  radius,  in  iV".  fmea  into  the  middle 
third,  and  in  Martes  into  the  distal  half  of  the  same  bone  ;  it  was  thick 
and  slightly  bilaminar  in  iVl  narica. 

Flexor  carpi  radialis  (015)  is  normal  in  all.  Palmaris  longus 
(•015)  has  two  heads — one  fleshy  and  the  other  tendinous  in  JV. 
narica 'f  the  insertion  is  into  the  palmar  fascia  in  all,  and  in  the 
marten  it  is  connected  with  the  superficial  abductor  minimi  digiti ; 
in  iV.  narica  there  is  an  accessory  palmaris,  arising  from  the  upper 
third  of  the  forearm,  overlying  the  ulnar  flexor  of  the  wrist,  and 
inserted  into  the  fascia  of  the  palm  by  a  slender  tendon.  Flexor 
carpi  ulnaris  ('03)  is  bicipital,  and  is  inserted  into  the  pisiform  as 
usual.  The  two  heads  are  united  at  the  middle  third  in  N,  fusca. 
Flexor  digitorum  sublimis  arises  from  the  flexor  digitorum  profiindis 
(just  above  the  annular  ligament  in  Martes),  and  is  inserted  by  four 
tendons  into  the  fascia  of  the  four  digits,  the  pollex  not  being  supplied 
by  it.  Flexor  digitorum  profundus  and  flexor  pollicis  longus  (condyloid 
part  -06,  radial  -08)  are  united,  have  the  usual  five  heads  (three 
median,  one  olecranal,  and  one  radial),  and  send  a  tendon  to  the  pollex 
and  to  each  of  the  digits ;  in  Martes  the  pollex  receives  its  tendon  from 
the  central  olecranal  head.  There  are  four  lumbricales  in  all,  one  on 
the  poUical  side  of  each  digit  tendon.  Pronator  quadratus  occupies 
the  lower  fourth  of  the  fore  arm  in  all. 

Supinator  radii  longus  ('04)  is  a  large  muscle  in  all,  arising  from  the 
external  ridge  of  the  humerus  and  inserted  into  the  distal  end  of  the 
radius.  Extensor  carpi  radialis  longior  (-02)  and  ex.  carp.  rad.  brevier 
are  quite  separate  in  N.fusca,  and  partly  so  in  N,  narica  and  Martes, 
and  have  the  usual  insertions.  Supinator  radii  brevis  occupies  the  upper 
two- thirds  of  the  radius  in  ^asua,  and  the  upper  half  in  Martes,  and 
has  no  sesamoid  bone  in  its  origin.  Extensor  digitorum  longus  (*02) 
arises  as  usual  from  the  outer  condyle  of  the  humerus,  and  is  inserted 
into  the  dorsal  aspect  of  each  of  the  four  digits.  Extensor  minimi 
digiti  ("01)  is  in  reality  an  extensor  of  the  third,  fourth,  and  fifth 
digits  in  N.ftisca  and  Martes,  sending  a  tendon  to  the  dorsal  aponeurosis 
of  each  of  those  fingers ;  but  in  iV.  narica  there  is  a  separate  extensor 
tertii  ct  quarti  digiti  ('015),  lying  in  the  same  groove  as  extensor 
minimi,  but  distinct  from  it.  Extensor  carpi  radialis  ('02)  has  a  very 
small  olecranal  origin,  and  no  ulnar  one  in  N.  narica,  but  is  large 
and  fiat  in  Martes  with  the  usual  origin  and  insertion.  Extensor 
oasis  metacarpi  pollicis  (about  '02)  arises  in  all  from  the  whole  length 
of  the  ulnar  and  interrosseous  membrane,  and  is  inserted  into  the 
radial  sesamoid    of  the  carpus ;    it  is  a   large   muscle   in   N.  fusca. 


Mackintosh — Notea  on  the  Myology  of  the  Coati-Mondi,  Sfc.   53 

Exte^^or  secnndi  intemodii  poUicis  et  indicis  is  single-headed  in 
the  coatis  and  bicipital  in  the  martins,  the  tendons  in  the  latter  uniting 
and  then  diverging  to  be  inserted  (as  in  N.  nama)  into  the  pollex  and 
index.  In  N.fusea  the  index  tendon  sends  a  very  fine  tendinous  slip  to 
the  middle  finger ;  there  is  also  in  this  animal  a  thin  palmaris  brevis 
extending  over  the  flexor  tendon  of  the  thumb. 

The  muscles  of  the  fore  foot  in  N.fusea  are — a  short  abductor  poUicis; 
an  adductor  from  the  front  of  the  carpus ;  a  double  abductor  indicis, 
one  head  arising  from  the  carpus,  and  one  from  the  metacarpus,  both 
uniting  to  form  a  single  tendon  ;  a  bicipital  adductor  indicis ;  a  single- 
headed  abductor  and  adductor  medii ;  an  adductor  minimi  digiti  arising 
from  the  pear-shaped  pisiform,  and  by  a  slip  from  the  unciform;  a 
flexor  brevis;  an  abductor  minimi  digiti,  as  usual;  an  abductor  and 
abductor  annularis,  also  normal.  The  interossei  are  normal  in  iV.  narica. 
In  Martes  there  are  an  abductor  poUicis,  extending  from  the  radial 
sesamoid  and  annular  ligament  to  the  pollex ;  an  abductor  pollicis  and 
flexor  brevis  pollicis,  both  normal ;  an  abductor  minimi  digiti,  arising 
from  the  pisiform ;  and  an  adductor  minimi  digiti,  from  the  front  of 
the  carpus;  a  flexor  brevis  minimi  digiti,  from  the  unciform;  and  an 
opponens  minimi  digiti,  which  is  a  dismemberment  of  the  abductor ; 
there  are  besides  two  interossei  for  each  digit. 

In  the  hind  limb : — Sartorius  ('08)  in  the  coatis  has  a  wide  origin 
from  the  anterior  superior  spine  of  the  ilium  as  usual,  and. a  double 
insertion — one  the  ordinary  tibial  insertion,  and  the  other  into  the 
patella  and  border  of  the  condyle  of  the  femur ;  in  N,  fwca  the  tibial 
portion  has  its  upper  part  attached  to  gracilis.  In  Martes  it  arises  from 
the  angle  of  the  crest  of  the  ilium  and  from  the  inferior  edge  of  that 
bone,  and  is  inserted  into  the  patella  and  fascia  of  the  upper  extremity 
of  the  tibia  along  with  gracilis. 

Psoas  parvus  ('03)  is  small  in  iV.  narieaj  and  sends  a  slip  to  the 
lumbo-sacral  articulation  ;  in  N,  ftuca  it  is  wide  and  strong,  with  the 
usual  attachments,  and  in  Martes  it  arises  fr^m  the  bodies  of  the  third, 
fourth,  fifth,  and  sixth  lumbar  vertebrae,  and  is  inserted  as  usual  into 
the  pectineal  line.  Iliopsoas  ('12)  is  normal  in  N,  narica ;  in  N.fiuca 
it  fs  a  psoas  major,  with  a  small  iliac  origin  ;  in  Martes  it  arises  from 
the  three  lower  lumbar  vertebrae,  is  inserted  fleshy  into  the  pectineal 
line,  and  by  a  tendon  into  the  lesser  trochanter. 

Pcctineus  ('04)  has  the  usual  origin,  and  is  inserted  into  the  upper 
half  of  the  femur  in  the  coatis,  and  into  the  upper  fourth  in  the  martins. 
Adductor  primus  (*09)  is  normal  and  quite  distinct  in  l^asua;  in 
Martes  there  is  a  second  slip  arising  from  the  posterior  half  of  the 
horizontal  ramus  of  the  pubis,  and  inserted  into  the  back  of  the  femur 
just  above  the  condyles.  Adductor  secundus  (+  adductor  tertius  '22) 
is  distinctly  bilaminarin  N,  narica^  biit  not  in  the  others ;  it  is  attached 
as  usual.  Adductor  tertius  is  separable  with  difficulty  from  adductor 
secundus,  arising  in  N.fusea  from  the  spine  of  the  pubis,  and  having  a 
narrow  insertion  into  the  middle  point  of  the  femur.  In  Martes  it  is  a 
small  slip  arising  just  in  front  of  the  pectineus,  and  behind  the  pecti- 


54  Proceedings  of  the  Royal  Irish  Academy* 

neal  tubercle;  its  insertion  overlies  that  of  pectineus.  Qu^ratus 
femoris  ('04)  arises  as  usual  from  the  tuber  ischii  anterior  to 
tiie  origin  of  biceps,  and  is  inserted  into  the  intertrochanteric  line. 
Obturator  extemus  (07)  and  iuternus  ('05)  are  both  present  and 
separate  in  all ;  the  superior  gemellus  is  large  in  N,  narica,  but  the 
inferior  is  absent ;  both  are  present  and  distinct  in  iT.  fusca,  and  they 
are  fused  with  obturator  in  Martes. 

Agitator  caudee  ('06)  in  N.  nariea  arises  from  the  first  caudal  ver- 
tebra, and  is  inserted  into  the  lower  two-thirds  of  the  outside  of  the 
femur  ;  it  is  represented  by  the  caudal  origin  of  the  biceps  in  Martes. 
Pyriformis  ('05)  arises  from  the  third  and  fourth  sacral  vertebrae, 
and  is  inserted  as  usual  just  behind  the  tendon  of  the  gluteus  medius. 
Gluteus  maximus  ('07)  arises  from  the  gluteal  fascia  and  first  cau- 
dal vertebra  (and  firom  the  side  of  the  sacrum  as  well  in  Martes),  and 
is  inserted  into  the  great  trochanter,  and  more  especially  into  its  pro- 
minent lower  part  in  the  coatis.  Gluteus  medius  (*15)  is  large  and 
normal.  Gluteus  minimus  (+  gluteus  quartus  '03)  is  fused  with  gluteus 
quartus  in  N»  nariea,  though  separate  from  it  in  N./usca  ;  the  latter  is 
absent  in  the  martins.  Tensor  vaginsB  femoris  ('05)  is  small  and  normal 
in  N.  nariea,  arises  from  the  anterior  superior  spine  of  the  ilium  in  N, 
fuaea,  and  from  the  inferior  edge  of  that  bone  in  Martes,  and  is  inserted 
into  the  fascia  of  the  thigh  as  usual ;  it  is  scarcely  separable  from  gluteus 
maximus. 

Biceps  femoris  ('17)  arises  in  Nasua  from  the  tuber  ischii,  and  in 
Martes  from  the  first  and  second  caudal  vertebrae  as  well,  and  is  inserted 
in  N,  nariea  into  the  upper  two-thirds  of  the  leg;  in  N,  fusca  into  the 
upper  half,  and  in  the  martin  into  the  fascia  of  the  thigh  and  upper 
half  of  the  tibia.  Biceps  accessorius  ('02)  arises  along  with  agitator 
caudee,  and  is  inserted  along  with  biceps  in  N.  nariea  ;  it  arises  along 
with  the  caudal  head  of  semitendinosus,  and  is  inserted  into  the  middle 
of  the  fibula  in  N.fusca ;  it  was  not  distinct  from  biceps  in  the  martin. 
Semimembranosus  (*  11)  in  the  coatis  is  united  to  adductor  primus 
except  at  its  insertion,  which  is  tibial  as  usual ;  in  Martes  it  is  quite 
separate,  extending  from  the  tuber  ischii  to  the  top  of  the  tibia. 
Semitendinosus  (*11)  arises  in  Nasua  by  two  heads — one  from  the 
tuber  ischii  as  usual,  and  the  other  tendinous  from  the  first  caudal 
vertebra  ;  they  unite  at  the  inscription,  which  is  about  halfway  down 
the  muscle,  and  are  inserted  as  usual  into  the  tibia  close  to  sartorius. 
There  is  only  the  single  ischial  head  in  Martes,  and  the  insertion  is 
into  the  tibia  at  the  point  of  junction  of  the  upper  and  middle  thirds. 
Gracilis  has  a  wide  origin  from  nearly  the  whole  of  the  horizontal 
ramus  of  the  pubis,  and  is  inserted  into  the  tibia,  inseparably  from 
sartorius  in  N,  nariea,  but  distinct  from,  although  closely  applied  Jbo,  it 
in  iV.  fusca, 

Eectus  femoris  ('10)  has  one  head,  and  is  moderately  separate  from 
vastus  extemus  ('14),  which  is  normal  and  distinct  from  vastus  inter- 
nus  (+  crurseus  '06),  the  latter  being  inseparable  from  crurseus.  Qua- 
driceps extensor  cruris  presents  no  feature  of  importance  in  Martes,  all 


Mackintosh — Notes  on  the  Myology  of  the  Coati-Mondh  8fc.    65 

its  parts  being  more  or  less  fused.  Popliteus  ('03)  is  normal  and  devoid 
of  a  fabella  in  N,  nariea,  with  an  insertion  into  nearly  the  upper  half 
of  the  tibia  in  N.fusea:  in  Martes  there  is  a  sesamoid  in  the  tendon  of 
origin,  the  insertion  is  into  the  upper  half  of  the  tibia  in  one 
specimen,  and  into  the  upper  third  in  the  other  (smaller)  ona 
Gastrocnemius  externus  ('06)  has  a  fabella,  and  is  inseparable  from 
the  next  muscle  at  its  origin  in  the  coatis ;  there  is  a  fabella  in  the 
origin  in  the  larger  of  the  two  martins.  Gastrocnemius  internus  ('07) 
has  no  sesamoid  in  N.  nariea  and  Martes,  but  there  is  a  small  one  in  N. 
ftuca.  Flantaris  (05)  has  the  usual  origin  and  insertion  (plantar 
fascia) ;  there  is  a  sesamoid  in  its  origin  in  the  coatis,  but  not  in  the 
martins,  in  which  animals  this  muscle  is  surrounded  by  gastrocnemius 
externus. 

Solseus  ('05)  is  fibular  in  origin  and  calcaneal  in  insertion  as  usual ; 
it  is  entirely  fleshy  in  Nasua  and  in  one  of  the  martins,  in  the  other, 
however,  there  is  a  tendinous  origin  becoming  fleshy  about  half  way 
down  the  leg. 

Flexor  digitorum  longus  (-04)  and  flexor  hallucis  longus  ('08)  are 
both  normal,  the  latter  being  as  usual  the  larger.  They  unite  to  form 
a  single  tendon,  which  again  subdivides  to  send  one  tendon  to  each  of 
the  five  digits.  Tibialis  posticus  (-04)  arises  as  usual  in  Nasua,  and  is 
inserted  into  the  astragalus,  scaphoid,  and  internal  cuneiform  bones;  in 
Martes  the  origin  is  very  high  up  on  the  tibia,  and  the  insertion  is  into 
the  scaphoid  only.  Flexor  digitorum  brevis  (-01)  arises  from  the  tendon 
of  plantaris,  and  is  in  fact  the  fleshy  part  of  that  muscle  on  the  sole  oi 
the  foot ;  it  sends  a  tendon  to  each  of  the  four  digits.  Flexori  longo 
accessorius  ('02)  arises  from  the  calcaneum,  and  is  inserted  into  the 
side  of  the  tendon  formed  by  the  union  of  flexor  hallucis  and  flexor 
digitorum. 

Tibialis  anticus  ('17)  is  single  and  normal  in  Nasua,butin  Martes 
there  are  two  separate  muscles — one  arising  a  little  behind  the  other 
from  the  top  of  the  tibia ;  the  two  tendons  are  inserted  side  by  side. 
Extensor  hallucis  (-02)  arises  from  the  upper  half  of  the  tibia,  and 
has  the  usual  hallucal  insertion  in  Nasua,  but  is  absent  altogether  in 
the  martins.  Extensor  digitorum  longus  ('03)  arises  as  usual  from  the 
external  condyle  of  the  femur,  and  sends  a  tendon  to  each  of  the  four 
digits.  Peroneus  quinti  ('01)  brevis  ('03),  and  longus  (-04),  present 
no  deviation  from  the  ordinary  carnivore  type.  Abductor  ossis 
metarsi  minimi  digiti  is  large  in  all,  arising  from  the  under  surface 
of  the  calcaneum,  and  inserted  into  the  base  of  the  fifth  metatarsal. 
Extensor  brevis  minimi  digiti  ('01)  is  normal  in  the  coatis.  In  N, 
fiuea  there  is  an  abductor  and  an  adductor  for  each  digit,  adductor 
indicis  being  bicipital.  In  N.  nariea  the  muscles  of  the  hind  foot 
are — Adductor  hallucis,  extending  from  the  head  of  the  middle 
metatarsal  to  the  outer  sesamoid  bone ;  abductor  and  flexor  brevis  hal- 
lucis, normal;  and  interosseous  abductor  and  adductor,  each  for  index; 
medius  and  annularis,  and  the  latter  of  the  two,  for  minimus,  which 
has  a  special  abductor ;  there  is  also  a  special  abductor  for  the  hallux. 


56  Proceedings  of  the  Royal  IrUh  Academy. 


IX. — Ow  80MB  Points  in  Bied  Myology.     By  A.  Macalister,  M.B., 
Professor  of  Comparative  Anatomy,  Dublin  University. 

[Read  April  27, 1874.] 

The  difflcnlties  in  the  classification  of  birds  have  led  many  recent 
zoologists  to  seek  for  special  principles  of  classification  whereby  to 
subdivide  that  exceedingly  compact  and  natural  class ;  but,  except  the 
skull-classification  of  Professor  Huxley,  there  hsis  not  been  anything 
proposed  more  satisfactory  than  the  old  Cuvierian  arrangement. 

The  active  and  observant  prosector  of  the  Zoological  Society  of 
London,  Mr.  A.  H.  Garrod,  has  proposed  two  new  points  as  bases  of 
classification — one,  the  arrangement  of  the  nasal  bones  and  their  sur- 
rounding parts  ;  the  second,  the  varieties  in  the  muscular  system. 

The  author  of  the  '*  Omithologiskt  System ''  has  used  some  of  these 
muscular  characters  as  of  taxonomic  value ;  but  Mr.  Garrod,  from  an 
extensive  range  of  dissections,  has  tried  to  use  the  presence  or  absence 
of  some  muscles  as  elements  in  classification. 

The  muscles  used  thus  by  Mr.  Garrod  are:  Ist,  the  caudo-femo- 
ralis — ^a  muscle  which  passes  from  the  tail  to  the  linea  aspera ;  2nd, 
the  quadratus  femoris,  which  extends  from  the  ischium  to  the  femur, 
above  the  last  (this  muscle  Mr.  Garrod  calls  accessory  femoro-cau- 
dal ;  but  it  is  most  probably  the  homologue  of  the  quadxatus  femoris, 
as  its  nerve  arises  high  up  from  the  roots  of  the  nervus  tibialis) ;  3rd. 
the  semitendinosus ;  4th,  the  femoral  head  of  the  semitendinosus;  5th, 
the  long  muscle  (called  rectus  by  Meckel,  gracilis  by  Cuvier,  Owen, 
and  Huxley,  but  named  ambiens  by  Mr.  Garrod). 

Mr.  Garrod  divides  birds  into  two  great  groups— those  with  and 
those  without  a  rectus  femoris.  Those  with  he  calls  Homalogonati ; 
those  without  he  calls  Anomalogonati.  Among  the  Homalogonati, 
however,  he  includes  the  Stork,  Pelican,  Jabiru,  and  Ardeidae,  as  well  as 
the  Owl,  Grebes,  and  Auks,  none  of  which  possess  such  a  muscle. 

Among  the  Anomalogonati  there  is  not  much  of  myological  varia- 
tion. Macrochires  have  no  quadratus  nor  semitendinosus,  and  this 
Mr.  Garrod  has  noted.  CoccygomorphsB  and  Passerinse  resemble  each 
other  in  having  no  quadratus  but  a  semitendinosus ;  but  while  Cu* 
cuius  has  a  rectus,  smd  belongs  to  the  next  group,  the  others  of  the 
order  do  not.  If  the  rectus  be  of  true  taxonomic  value,  the  Ardeidse, 
PodicipidsB,  Alcidae,  and  Phcenicopteridae  should  be  introduced  here. 

The  Homalogonati  are  more  variable.  The  femoro-caudal  is  absent 
in  the  Ostrich,  Grebe,  Otis,  and  Flamingo ;  in  the  last-named  we  failed 
to  find  a  rectus  femoris,  though  Mr.  Garrod  has  found  one ;  so  this 
muscle  appears  to  be  subject  to  variety.  The  Pelican,  likewise,  we 
found  to  have  no  femoro-caudal,  though  Sula  has  one,  and  also  Phala- 
crocorax.  The  quadratus  femoris  is  absent  in  Parrots,  Pelicans, 
and  Storks,  according  to  Mr.  Garrod ;  but  here  there  are  also  ele- 
ments of  variety;  for  in  PelicanxM  onocrotahis  and  Ciconia  alba  I  have 


Macalister. — On  some  Points  in  Bird  Myology ^  67 

found  it  present,  and  while  in  Seagulls  it  is  absent,  in  the  Albatross  it 
is  present,  and  it  also  exists  in  Sula. 

These  are  but  specimens  of  the  result  of  the  application  of  myolo- 
gieal  varieties  for  primary  taxonomic  purposes. 

Muscular  characteristics  have  undoubtedly  a  very  great  secondary 
importance  in  classification,  and  as  subordinate  order  and  family  cha- 
racters, none  are  more  important ;  but  they  seem  to  fail  utterly  when 
we  take  them  primarily  or  alone,  and  try  to  frame  a  system  by  them. 

There  are  other  muscles  which  may  be  utilized  for  these  secondary 
classificatory  purposes,  as  variable  among  birds.  The  iliacus,  which  is 
absent  in  the  Phasianidae  (probably  in  all  the  Rasores),  but  present  in 
Pelargomorphse,  GecomorphsB,  AetomorphsB,  Geranomorphse,  &o.  A 
separate  gluteus  minimus,  distinct  from  gluteus  quartus,  is  a  rarely 
present  muscle  (Lophophorus).  The  second  vasti  are  also  important 
bird  muscles,  and  the  popliteus,  which  may  be  femoro-tibial  or  fibulo- 
tibial.  The  soleus  is  also  variable  in  its  existence,  present  in  Sula 
Mycteria,  Ciconia.  The  plantaris  is  a  constant  muscle,  and  only  varies 
in  the  distribution  of  its  extended  tendons,  which  may  go  to  the 
second,  third,  or  second,  third,  and  fourth  toes.  The  flexor  digitorum 
sublimis  is  very  constant  in  all  birds,  with  its  two  perforating  ten- 
dons. The  tibialis  anticus  is  also  constant,  with  its  two  parts,  femoral 
and  tibial.  The  peroneus  longus,  which  is  so  constant,  winding 
round  the  outside  of  the  knee,  and  extending  into  the  perforating 
flexor  of  the  middle  digit,  may  rarely  have  no  digital  extension  (Crax) ; 
Peroneus  brevis  is  variable;  present  in  .the  Albatross,  Eagle,  Khea, 
Heron ;  but  absent  in  the  Stork  and  Pelican. 

Among  the  forelimb  muscles,  the  infraspinatus  is  the  most  variable 
in  its  presence,  the  muscle  usually  called  such  being  the  teres  major ; 
it  is  small,  distinct,  and  ribbon-like  in  Lophophorus,  Crax,  Ithaginis, 
and  Sula ;  absent  in  Tetrapteryx. 

The  homologues  of  the  shoulder  muscles  in  birds  can  only  be  deter- 
mined with  accuracy  by  a  study  of  their  nervous  supply.  Those  of 
the  hip  muscles  are  little  less  d^cult. 

As  Professor  Selenka  has,  in  his  admirable  part  of  Bronn's  Thier- 
reichs,  figured  the  brachial  plexus  of  a  bird, '  I  have  endeavoured  to 
do  the  same  for  the  lumbar  and  sacral  plexus  of  TetrapUryx  Stan- 
leyanus  in  the  woodcut  on  next  page. 


B.  I.  A.  PBGC,  8ER.  XL,  TOL.  II.,  BCIKSCE. 


58  Proceedings  of  the  Itoytd  Irish  A  cademy, 

LnifBAB  AND  Sacral  Plrxus  of  TdrapUryx  SUmUyanut, 


X.-  The  Pbesence  of  a  IiACHHTico-JiroAL  Suture  in  a  Huuan  Skull, 

AND  ON  ITS  COMPABATIVE    AnATOMT.       By    A.    MaCALISTER,    M.  B., 

Professor  of  Comparative  Anatomy,  Dublin  University.      (With 
Plate  1.) 

[Read  Noyember  9th,  1874.] 

The  relation  of  the  processus  maxillaris  of  the  jugal  bone  to  the 
supraorbital  edge  of  the  maxillary  is  subject  to  a  considerable  amount 
of  variety.  In  the  largest  number  of  ordinary  European  crania  this 
process  ends  at  a  point  vertically  over  the  infra-orbital  foramen,  or 
over  the  space  between  the  first  and  second  premolar  tooth.  The  fol- 
lowing Table  shows  accurately  the  relationships  of  this  process,  as 
noted  in  connexion  with  collateral  points  in  204  skulls : — 


MACAi.iST£K — Lachrymo-jugal  Suture  in  a  Hainan  SkulL     oD 


£i 


b8«. 

u 


H 

II 


Indo-Gennanic  Skulls 
Turanian  „ 

A&iean  „ 

Australian  „ 

American  ,, 

Polynesian  and 


93 
5 

10 
0 
9 


rolynesian 
HaUy 


24 
0 
18 
10 
17 

11 


10 
!♦ 
0 
0 
0 


14 


Total 


118 


80 


11 


14 


In  only  one  gkull  of  all  those  examined  have  I  seen  the  arrangement 
rderred  to  in  the  title  of  this  Paper.  The  specimen  is  a  male  British  (?) 
sknll  which  I  found  in  the  Museum  of  the  Dublin  University.  There 
is  no  history  of  the  specimen,  which  is  numbered  29  in  the  collection, 
and  whichi  in  the  late  Dr.  Ball's  manuscript  catalogue,  is  marked 
"  Skull  purchased. — J.  Abell's.''  The  skull  is  a  strongly  marked  one, 
with  prominent  supra-orbital  ridges,  having  on  the  lefb  side  a  supra- 
orbital foramen,  and  on  the  right  a  groove.  From  these  pass  up- 
wards and  outwards,  on  each  side,  deep  grooves,  wherein  lie  the 
supra-orbital  nerve  and  artery,  and  this  vessel,  on  the  left  side, 
seems  to  have  ended  by  dipping  into  the  bone.  The  nasal  bones  are 
very  large  and  prominent,  and  there  is  a  high  Wormian  bone  on  each 
spheno-parietal  suture.  The  ezoccipital,  on  its  lower  side,  sends  out  flat, 
paracondyloid  spurs  on  each  side,  which  overlap  the  groove  for 
the  oceipital  artery;  but  they  have  no  cartilage  encrustations,  as 
in  the  case  described  by  Uhde  (Archiv  fiir  KUnische  Chirurgie, 
viii.  1).  The  alisphenoid  has  on  each  side  a  foramen  in  the 
middle  of  its  temporal  crest.  The  processus  tubarius  of  the  ento- 
pterygoid  (Bebsamen,  Monatschrift  fiir  Ohrenheilkunde,  1868, 
No.  3)  is  unusually  extended  as  a  thin  lamella,  backwards  and  out- 
wards, and  projects  sharply  on  the  lower  surface  of  the  hinder  acces- 
sory root  of  the  great  wing.  The  side  of  the  spina  angularis  completes 
the  articular  cavity  for  the  mandible  which  it  has  touched.  The  pala^ 
tine  surface  shows  some  irregularity  of  suturation ;  the  left  horizontal 

*  A  Japanese  skull,  with  an  approach  to  the  arrangement  here  described,  but 
the  hamulus  laehrymalis  is  very  short,  and  hence  there  is  0'26"  between  the  malar 
and  jugal  bonse. 


60  Proceedings  of  the  Royal  Irish  Academy. 

plate  of  the  palate  at  tlie  median  suture  ia  only  three  lines  long,  from 
before  backwards,  while  the  right  exceeds  four  lines.  There  is  also  a 
trace  of  premaxillo-maxillary  suture  on  this  aspect.  The  ethmoidal 
spine  of  the  sphenoid  is  trefoil- shaped,  with  two  alsB  minimas 
(Luschka).  There  is  a  carotico-clinoid  canal  on  the  right,  but  only  a 
stumpy  middle  clinoid  process  on  the  left. 

The  right  malar  bone  has  an  exceedingly  long  maxillary  process 
extending  as  far  as  over  the  canine  tooth,  and  four  lines  internal  to 
the  infra-orbital  foramen.  The  root  of  the  process  is  slightly  concave 
below,  excavated  for  the  orbital  head  of  the  levator  labii  superioris. 
Its  anterior  end  is  separated  from  the  outer  hamulus  of  the  lachrymal 
bone  by  a  slender  isthmus  of  the  margolachrymalis  of  the  maxilla  0*7 
of  a  line  broad.  This  margin  directly  behind  the  tip  of  the  malar  has 
a  transverse  suture  and  a  small  foramen.  On  this  side  there  is  no 
sutura  infra-orbitalis  transversa,  but  the  nasal  process  of  the  maxilla 
has  an  oblique  vascular  groove.  The  malar  is  excluded  on  this  as  on 
the  left  side  firom  forming  the  anterior  boundary  of  the  spheno-maxil- 
lary  fissure,  as  there  is  a  sphenoidal  process  of  the  maxilla.  On  the 
left  side  the  processus  maxillaris  is  still  more  extensive,  and  stretches 
over  the  whole  infra- orbital  edge  of  the  maxilla ;  crossing  the  margo- 
lachrymalis to  join  internally  the  end  of  the  crista  lachrymalis,  it 
bridges  over  an  imperfect  sutura  infra-orbitalis,  and  stretches  in  front 
of  the  large  external  hamulus  of  the  lachrymal  bone,  with  which  it 
forms  a  suture  of  about  a  line  and  a  half  in  length.  The  lachrymal 
and  malar  thus  form  a  complete  belt,  excluding  the  maxilla  from 
forming  any  part  of  the  brim  of  the  orbit.     (Plate  1,  fig.  1.) 

As  will  be  seen  from  the  Table,  such  an  extreme  case  of  inward 
extension  seems  to  be  unique  ;  at  least  I  know  of  no  record  of  such  a 
condition. 

Turning  to  the  comparative  anatomy  of  the  processus  maxillaris, 
we  find  that  in  the  anthropoids  the  proc.es8Us  does  not  extend  even  as 
far  inwards  as  in  man.  In  the  Gorilla  (3  skulls)  the  process  falls  short 
of  the  infi^-orbital  foramen.  In  the  Orang  (1  skull)  it  falls  still  farther 
short.  In  the  Chimpanzee  ( 1  adult  and  5  young  skulls)  it  also  falls  short. 
In  Hylobates  Siamanga  (1  sp.)it  extends  to  the  level  of  the  foramen.  In 
Inuus,  Gercopithecus,  &c.,  it  falls  short  considerably,  or  else  stretches 
nearly  to  the  level.  The  only  one  of  the  Quadrumanous  Primates 
wherein  I  found  a  lachrymo-jugal  suture  present  was  a  Khesus,  spe- 
cies unknown,  in  which  the  large  lachrymal  bone  forms  the  entire 
circumference  of  the  depression  for  the  lachrymal  sac^  and  the  long 
square  malar  sends  in  on  each  side  a  processus  maxillaris  to  articulate 
with  the  edge  of  the  former.     (Plate  1,  fig.  2.) 

Among  the  Platyrrhines  there  is  no  trace  of  such  a  suture  in  Ce- 
bus,  Mycetes,  Ateles,  or  Callithrix.  The  Marmosets  (Hapale)  have 
the  short  wide  processus  maxillaris  far  from  the  lachrymal,  and 
among  the  Lemurs  there  is  no  union  or  lachrymo-jugal  contact  in 
Tarsius,  Lepilemur,  Stenops  or  Lemur. 

Among  Chiroptera  there  is  no  lachrymo-jugal  suture  in  any  genus 


Macalister — LachrymO'jugal  Suture  in  a  Human  SkulL    61  • 

which  I  have  examined.  I  have  failed  to  find  it  in  Chiromys  and 
GhJeopithecuB,  as  well  as  in  the  other  Insectiyores. 

Among  Camivores  and  Cetaceans  no  such  suture  exists ;  and,  in  the 
order  Bodentia,  the  lachrymal  bone  shows  a  facial  as  weU  as  an  orbi- 
tal surface ;  but  the  zygomatic  process  of  the  maxillary,  which  in 
these  is  largely  developed,  intervenes,  and  no  suture  occurs  in  any 
form. 

In  the  aUied  order  Proboscidea  the  lachrymal  is  small,  ento-orbital, 
with  a  tubercle ;  but  the  small  malar  does  not  reach  near  to  it.  In 
Hyracoidea  the  lachrymal  is  similarly  arranged. 

AmoDg  Ungulates  the  Bhinoceros  has  the  suture  very  distinct, 
Bax>erficiaL'  The  Tapirs  have  a  very  well  marked  but  shorter  suture. 
The  Horses  are  similarly  but  more  fully  provided. 

All  Artiodactyles  have  an  extensive  facial  surface  of  the  lachrymal, 
and  a  long  lachrymo-jugal  suture;  largest,  proportionally,  in  the 
Bovidss,  smallest  in  the  Deer. 

Tylopoda  possess  a  sLmilar  suture,  but  usually  shorter  and  nar- 
rower. 

In  the  Figs  the  same  arrangement  obtains,  the  suture  being 
largest,  proportionally,  in  the  Fhacochoerus,  smallest  in  the  Peccaries. 
In  the  Hippopotamus  the  large,  thin- walled  lachrymal  bone  unites 
by  a  moderately  extensive  suture,  and  sometimes  anchyloses  to  the 
malar. 

Among  the  Sirenia  the  large  rough  malar  rests  internally  on  the 
scale- like,  small,  imperforate  lachrymal  in  the  Manatee,  or  on  the 
cubical,  solid  lachrymal  in  the  Dugong. 

In  Myrmecophaga  the  slender  malar  styles  have  a  wide  lachrymo- 
jugal  suture ;  indeed,  this  is  the  chief  attachment  of  the  malar  bone. 
The  Pangolin  (Manis  and  Pholidotus)  have  the  lachrymal  fasing  so 
early  with  the  maxilla  as'  to  be  lost  in  distinctness ;  but  in  young 
skulls  the  lachrymal  is  well  above  the  level  of  the  imperfect  zygoma. 

Armadillos  have  a  very  distinct  and  wide  union  of  this  bone,  and 
the  large  lachrymal  in  Orycteropus  expands  on  the  face  for  a  con- 
siderable extent  Bradypus  has  a  distinct  lachrymo-jugal  suture,  as 
also  is  the  case  in  the  two  species  of  Choloepusand  in  Ghlamydophorus. 
The  lachrymal  bone  in  Sarcophilus  has  a  distinct  lachrymo-jugal 
union.  In  Thylacinus  it  is  not  so  large,  but  arranged  as  in  the  former. 
Fhascolomys,  Didelphys,  Macropus,  Petaurus,  Phalangista,  Halma- 
turus,.  &c.,  all  agree  in  the  presence  of  such  a  suture. 

In  my  skulls  of  the  Monotremes,  Echidna  and  Omithorhynchus, 
Butural  marks  have  been  obliterated,  but  in  Omithorhynchus  I  think 
I  see  traces  of  such  lines,  indicating  a  lachrymo-jugal  contact. 

Thus  among  Mammals  the  suture  is  present  in  all  below  the 
Hyracoids,  absent  in  all  above.  In  man  there  is  even  less  tendency 
towards  its  occurrence  in  lower  and  aboriginal  races  than  in  the 
higher ;  thus  in  the  Yeddahs,  Negroes,  Esquimaux,  Fuegians,  Austra- 
lians, the  maxillo-jugal  suture  is  much  more  vertical  than  in  the 
skulls  of  more  civilized  races,  and  the  termiui^tion  of  the  malar  is 
almost  invariably  external  to  the  infra-orbital  hole  in  all  these. 


62  ProceedingM  of  the  Royal  Iriih  Academy. 


XL — Ow  tvoNbw  Spboibs  of  Psttastoma.  By  A.  Macalistbh,  M.B., 
Professor  of  Comparative  Anatomy,  Dublin  UniTersity.  (With 
Plates  2  and  3.) 

[Bead  NoTember  9,  1874.] 

In  dissecting  a  specimen  of  Boa  imperator  brought  home  by  Dr. 
Ajrmstrong  (of  the  Army  Medical  Service)  from  South  America,  I 
found  in  the  lung  and  peritoneal  cavity  about  six  specimens  of  a  Penta- 
stoma.  It  resembles  the  P.  pnAoicideum  of  Rudolphii  which  has  been 
found  in  the  allied  species  Boa  eomtrictor  as  well  as  in  Epierateu 
anffidifir,  Laeheeu  ep,,  and  a  species  of  Bothrops,  but  differs  specifically 
from  the  type  of  P,  prohomdeum^  as  well  as  from  the  subtypical  varieties 
of  that  species,  P.  elavaium  of  Wyman  and  P.  iubeylindrieum  of  Diesing. 

The  specimens  measure — the  females  45 -57mm,  the  males 
19-22mm  in  length.  In  breadth  the  females  are  3*3mm  at  the  head, 
l-27-2-28mm  at  the  narrowest  point  which  is  the  hinder  fourth,  and 
about  l*30-2'5mm  at  the  tail.  The  males  in  width  are  a  little  lees.  The 
body  is  annulated  posteriorly,  but  for  the  cephalic  half  the  rings  are 
not  very  clear;  each  ring  consists  of  a  wide  flat  belt  of  surface,  with 
a  slightly  cMtinized  epidermis,  and  a  thicker  hypodermis,  than  that  in 
the  intersegmental  zone.  The  head  is  convex,  rounded  posteriorly  and 
flattened  below ;  in  froat  and  below  it  projects  forward  as  an  anterior 
firm  ridge,  with  a  thick  chitinous  integument,  a  little  under  whose 
edge  are  the  two  pairs  of  hooks.  The  surface  of  the  body  is  finely  and 
rather  irregularly  ridged  in  some  places,  but  is  devoid  of  either  pro- 
cesses or  bristles.  On  the  back  of  the  vertex,  7mm  from  the  front,  there 
is  a  small,  raised,  flady-conical,  median  wart,  slightly  radially  ridged 
around  its  margin,  but  imperforate ;  in  front  of  this  are  five  or  six 
other  smaller  wartlike  surface-eminences. 

The  two  pair  of  books  are  sharply  curved,  acute,  hollow,  the  inter- 
nal cavities  extending  to  near  their  points :  they  have  each  an  inferior 
basal  spur,  elongated  anteriorly  for  muscular  attachment;  each  has  also 
a  bilaminar  basipodal  process,  to  which  also  the  muscular  lamellas  are 
attached.  These  hooks  are  dark  brown,  and  finely  longitudinally 
striated  in  some  places;  each  hook  is  about  0*6-0*28mm  in  length. 

The  mouth  is  elongated,  elliptical,  with  a  smooth  chitinous  peri- 
stomial  ring,  on  the  level  of  the  bases  of  the  median  hooks ;  it  leads 
into  the  scarcely  subdivided  digestive  tract.  The  cBsophagus  is  thin- 
walled,  with  no  proper  glandular  wall,  other  than  its  thin  lining 
epithelium ;  it  passes  over  the  receptaoulum  seminis,  and  between  the 
two  cirrus  pouches.  It  dilates  feebly  into  the  stomach,  an  elongated 
sac  with  longitudinal  glandular  ridges  on  its  wall,  and  here  and  there 
papillary  processes.  The  gland  cells  are  spheroidal,  deep  brown  in 
colour,  and  give  the  digestive  canal  a  deep  hue,  rendering  it  visible 
through  the  body  wall.    The  lowest  part  of  the  digestive  cemal,  or  the 


Macalister —  On  ttoo  New  Species  ofPenta^oma.        63 

iDtestine,  is  nearly  ooloorloBS,  thin-walled  with  slight  ridges,  slightly 
dilated  before  its  anal  end,  but  with  no  accessory  gland.  The  whole 
oanal  is  nearly  straight,  and  the  anns  is  apical.  The  average  diameter 
of  the  intestine  is  0'6mm.  In  none  of  the  specimens  was  it  enclosed 
in  the  tortnosities  of  the  oviduct,  nor  of  the  male  accessory  organs,  but 
these  lie  on  its  ventral  side.  There  is  an  outer  connective  coat  feebly 
separable,  and  containing  a  few  scattered  stellate  connective  coi*pn8cles; 
then  a  longitudinal  muscular  coat  of  striped  fibres,  but  I  could  detect 
no  tnu!e  of  circular  fibres,  such  as  Br.  Harley  found  in  P.  mtdttetnetum.* 
The  mucous  membrane  has  a  thin  structureless  basement  raised  into  the 
ridges,  and  covered  with  the  surface  stratum  of  glandular  epithelium. 
There  was  no  sign  of  a  corpus  adiposum  in  any  of  the  specimens. 
In  all  the  intestinal  tract  was  empty  or  nearly  so. 

The  body  wall  eonsisted  of — Ist,  an  outer  structureless  chitinous 
wall,  which  showed  no  traces  of  pore  canals,  nor  stigmata.  2nd,  a  very 
fine  and  irregularly  distributed  hypodennis,  containing  cells  with 
branched  processes.  3rd,  a  thick  longitudinal  stratum  of  striped  fibres; 
and  miz^  with  the  deeper  layer  of  this,  and  within  it  are,  at 
the  extremities,  circular  fibres.  The  body  cavity  within  this  is  lined 
by  a  soft  reticular  membrane,  but  I  could  not  detect  the  pavement 
epithelium  within,  which  Harley  noticed. 

The  nervous  system  consists  of  a  bilobed  epipharyngeal  nerve 
ganglion  sending  down  two  longitudinal  nerve  cords  pai^lel  to  the 
digestive  tubes.  These  seem  to  send  off  branches  into  the  body  walls, 
supplying  the  muscles,  I  saw  no  trace  of  a  hypopharyngeal  ganglion, 
nor  of  tibe  double  ganglion  described  and  figured  by  Blanchard  in 
P.  proboeeideum.  There  was  no  trace  of  a  metameric  series  of  gan- 
glia. There  is  no  heart  nor  circulatory  system,  but  a  milky  corpuscu- 
lated  "fluid  lies  in  the  perivisceral  cavity.  There  is  no  respiratory 
system,  nor  trace  of  tracheal  tubes,  so  the  breathing  process  is  evi- 
dently dermal  in  site. 

The  hooks  appended  to  the  head  have  muscular  bands  inserted  into 
their  basipodal  processes.  Each  hook  has  also  a  fan-shaped  depressor 
muscle,  which  is  only  a  specialized  part  of  the  longitudinal  muscular 
layer  of  the  body  wall.  Other  fibres  from  the  same  source,  but  forming 
with  them  an  angle  of  56^,  serve  for  the  elevation  of  the  hooks. 

The  reproductive  organs  are  the  only  complex  structures  in  these 
animals.  In  the  female  there  is  a  vulva  situated  immediately  in  firont 
of  the  anus ;  sometimes  these  orifices  are  so  close  together,  that  they 
appear  to  have  a  common  integumental.  lip  around  them,  but  usually 
the  vulva  has  a'  slightly  protruding  lip  of  its  own.  From  this  ascends  a 
slender  vagina  of  6- 12mm  in  length,  ending  in  the  slightly  dilated 
fusiform  uterus,  which  measures  25-80mm  in  length,  and  3mm  at  its 
widest  point.  This  is  thin- walled,  and  ends  above  in  a  narrow  oviduct 
which  ascends  at  first  directly  nearly  to  the  head,  and  there  turning  back- 
ward twists  on  itself,  forming  a  long  tortuous  closely  coiled  tube,  about 


♦  Proceedings,  Zoological  Society,  1866,  p.  116. 


64  Proceedings  of  the  Royal  Iriah  Academy. 

six  times  the  length  of  the  entire  body  (not  ten  times  as  in  P.  fnutU- 
einetum).  This  tube,  like  the  uterus,  is  transparent,  whitish  when 
empty  or  faintly  cream-colpured  when  filled  with  eggs,  contrasting 
thus  strongly  in  colour  with  the  dark  brown  digestive  tract.  It  has  a 
thin  basement  layer,  a  very  thin  muscular  coat  of  mixed  circular  and 
longitudinal  fibres,  not  in  separate  laminae,  and  these  fibres  are  striped 
(not  smooth  as  Harley  found  them  in  P.  multicinetum).  The  tortuous 
tube  in  some  of  the  females  was  so  full  of  eggs  as  to  distend  the  entire 
body,  so  that  on  a  section  being  made,  the  whole  perivisceral  cavity 
appeared  full  of  eggs.  In  one  specimen,  at  least  16,500  eggs 
existed. 

The  tortuous  oviduct,  when  traced  back  to  its  origin,  begins  as  a 
fine  tube  attached  to  the  medio-ventral  wall  of  the  body ;  at  the  second 
distinct  ring  behind  the  mouth,  and  on  each  side  of  it,  is  a  roundly 
ovate  sac,  fiill  of  spermatozoa  and  granule&  The  former  are  arranged 
in  bundles  or  spermaphores,  but  with  no  traces  of  thickened  cases. 
These  sacs  have  a  thin  proper  wall,  and  open  directly  into  the  oviduct 
at  its  commencement.  This  commencement  is  really  the  point  of  coa- 
lescence of  two  fine  tubes ;  the  ovarian  tubes,  which  arise  from  the 
cephalic  end  of  the  ovary,  and  running  a  short  course,  end  by  uniting 
between  the  ovate  reeeptaetda  teminii  to  form  the  oviduct  The  ovary 
is  a  thick-walled  single  tubular  gland,  extending  from  near  the  tail  to 
the  head,  containing  material  which  poRteriorly  appears  simply  granular, 
but  which  nearer  t^e  dacts  becomes  more  diiferentiated  into  rounded 
or  oval  masses  attached  to  a  central  axis. 

The  smaller  males  have  a  still  more  highly  complicated  apparatus. 
This  organ  consists  of  a  large  bilobate  testis  stretching  on  the  dorsal 
wall  of  the  body  cavity  as  tar  as  the  tail,  and  lying  over  the  alimentary 
canal.  Its  duct  or  vas  deferens  appears  at  the  upper  end  of  the  gland, 
runs  backward  towards  the  tail  for  a  very  short  extent,  and  then  turns 
forwards  again  looping  under  the  duct  of  one  of  the  accessory  glands. 
The  vas  deferens  then  divides  into  two  lateral  branches,  right  and  left, 
.which  pass  outwards  and  forwards,  each  ending  in  an  intromittent 
organ.  The  divided  extremity  of  the  vas  deferens  is  known  as  the 
annular  canal  whose  relation  can  be  seen  in  Plate  2,  fig.  6.  Into  each 
limb  of  the  annular  canal  posteriorly  there  opens  an  accessory  gland. 
These  are  long,  tortuous,  tubular  glands  placed  one  on  the  right  and 
one  on  the  left,  ventrad  of  the  testis,  thick-walled  and  lying  one  on  each 
side  of  the  vas  deferens.  The  right  of  these  crosses  over  the  loop  of  the 
vaa.  These  glands  secrete  the  glutinous  material  which  unites  the 
filamentary  spermatozoa  into  spermaphore  clusters.  The  concavity  in 
tront  of  the  annular  canal  is  occupied  by  two  lateral  elliptical  pouches, 
contiguous  in  the  mesial  line,  lying  under  tlie  digestive  tract,  and 
opening  on  the  surface  ventrally  in  fh>nt;  these  are  the  cirrus  pouches 
which  contain  the  intromittent  organs.  These  are  tubular,  the  pro- 
longed extremities  of  the  vasa  deferentia,  and  are  nearly  equal  in  length 
to  half  the  animal's  body.  Each  of  these  having  preserved  a  uniform 
calibre  for  most  of  its  extent,  ends  by  suddenly  dilating,  then  narrow- 


Macalister — On  two  N^to  Species  of  Pentastoma.         65 

ing  to  a  fine  point ;  by  these  organs  the  spermatozoa  are  conveyed 
upward  on  their  long  joomey  to  the  spermaphores  of  the  female. 

As  anterior  diverticula  from  these  are  two  lateral  thick- walled  sacs 
each  lined  with  a  ridged  and  processed  chitinous  membrane.  These 
accessory  sacs  are  hollow,  and  their  chambers  communicate  with  each 
other  by  a  transverse,  anterior,  annular  canal  over  the  oesophagus. 
The  use  of  these  sacs  is  unknown.  These  cirrus  pouches  and  their 
accessory  parts  are  much  larger  than  in  P.  toBnioides^  where  these  organs 
are  small  and  limited  to  lateral  areas  beside  the  chitin  sac-organs. 

The  ova  were  found  in  several  stages  of  development  in  some  of  the 
females,  from  the  perfectly  undeveloped  egg  with  germ-spot  and 
vesicle  to  the  bi  or  multipartite  cleft  yelk  of  the  fertilized  egg.  In 
some  of  the  latter  the  spherules  were  very  disproportionate  in  size, 
some  six  times  the  size  of  the  others,  and  the  larger  always  had  a  ten- 
dency to  one  side  or  surface  of  the  ovum.  The  eggs  are  holoblastiOf 
and  segmentation  ends  in  the  formation  of  a  blastoderm.  There  are 
polar  groups  of  cells  visible  in  some  ova  and  a  trace  of  primitive  streak, 
subdividing  the  tail  end  of  the  egg  into  two  lateral  parts.  When  the 
body  forms  as  a  granular  mass  six  lateral  lobules  project  downwards 
and  outwards,  two  of  which  unite  to  form  the  basis  of  the  antennary 
jaws  of  the  head,  two  form  the  larval  forelimbs,  and  the  hindmost  pair 
form  the  hind  legs.  The  first  and  second  pair  of  these  form  first,  the 
hindmost  afterwards.  In  several  of  the  hundreds  of  ova  which  I 
examined  I  saw  a  faint  trace  of  annulation,  one  or  two  transverse  fur- 
rows, indication  of  a  metameric  growth.  In  one  embryo  which  is 
obliquely  shown  (Plate  8,  fig.  11)  these  are  indicated  (and  rather  exag- 
gerated), and  two  of  the  limbs  are  shown,  armed  with  paired  claws.  lu 
tiie  earlier  stages  before  the  claws  appear  the  knobs  look  like  the  para- 
podia  of  worms,  but  a  middle  transverse  joint  in  each  of  these  limb 
knobs  is  indicated  in  some  of  my  specimens.  Two  free  embryos  fur- 
ther developed  than  any  of  those  enclosed  in  the  egg  membraues  are 
shown  Plate,  figs.  1 2  and  13*  In  these  the  larval  form  is  easily  recognis* 
able.  In  no  stage  nor  specimen  did  I  see  a  trace  of  the  simple  salivary 
gland  which  exists  in  A  iomioides. 

The  adult  hooks  are  not  the  descendants  of  the  embryonic  limbs, 
but  seem  to  indicate  segments  anterior  to  the  three  limb-bearing 
segments  of  the  larva.  The  extremely  complex  subsequent-develop- 
mental stages  I  had  no  means  of  investigating.  ^ 

In  the  above  observations  I  have  refrained  from  quoting  from  the 
classical  memoir  of  Leuckart  on  the  Pentastomidse,  our  chief  source 
of  information  on  these  aberrant  arthropods,  as  1  wish  to  make  this 
Paper  only  a  record  of  direct  observation. 

We  may  summarize  the  specific  characters  of  this  species  thus : 
Pentaaioma  imp&ratoris^  body  with  40-45  rings,  clearly  annulated 
behind,  more  indistinctly  in  front ;  head  acutely  wedge-shaped  with 
no  lateral  stigmata,  but  with  several  median  dorsal  warts  ;  hooks 
simple  with  slender  basal  processes;  vulva  very  close  to  the  vent ;  pos- 
terior end  dilated  pyriform,  with  its  narrowest  end  termioal ;  stomach 

B.  I.  A.  PBOO.,  SBIL  II.  VOL.  11.,  SCIXKCB.  K 


66  Proceedings  of  the  Royal  Irish  Academy. 

Bcaroely  dilated ;  males  slightly  incarved  at  the  tail ;  dimensions  as 
above. 

The  other  species,  P.  Aonyets,  of  which  I  have  only  obtained  two 
specimens,  both  females,  occurred  in  the  peritoneal  cavity  of  the  large 
Indian  Otter  from  the  river  Indus  {Aonyx  leptonyx  var.  Ifayoii)  sent  home 
by  the  late  Earl  of  Mayo  to  the  Dublin  Zoological  Gardens  (whose 
anatomy  I  have  described  in  the  Proceedings  of  this  Academy,  Vol.  I. 
Series  II.,  Science,  p.  639).  These  parasites  measured  17-20mf7i.  in 
length,  and  were  straight,  elongated,  acuminated,  with  nearly  conical 
apex  and  an  obtusely  truncated  head  which  is  25mm,  in  width.  It  is 
closely  annulated  with  30  rings,  each  of  which  is  sharply  defined  and 
separated  from  its  neighbours  by  a  sharp-edged,  square-profiled  furrow. 
These  rings,  from  being  very  wide  (0^7 mm.)  posteriorly,  become  very 
narrow  in  front  and  cease  to  be  distinct  at  the  head.  The  mouth  has  two 
lateral  chitinous  lip-ridges,  one  on  each  side.  The  two  pair  of  hooks  are 
elongated,  acute,  with  longer  basal  fulcra  than  in  P.  imperatoris  (four 
times  the  length  of  the  exserted  portion  of  the  hook),  but  with  a  much 
shorter  basal  process.  There  is  a  single  bilobed  epipharyngeal  nerve 
ganglion,  and  the  oviduct,  ovary,  and  digestive  tract  are  arranged  on 
the  same  plan  as  in  P,  imperatoris. 

The  surface  of  the  skin  is  covered  over  with  numerous,  irregularly 
arranged  circular  dots  with  depressed  edges  ;  these  are  most  numerous 
about  the  head  and  forepart,  but  become  fewer  posteriorly.  There 
were  no  ova  in  any  forward  state  of  development. 


XII. — On   the   MirscrLAR  Anatomy  or  Ceolcepus  Didacttlus,     By 
H.  W.  Mackintosh,  B.  A.     (With  Plate  4.) 

[Bead  November  9,  1874.] 

In  the  month  of  January  last,  Professor  Macalister  having  purchased*  a 
fine  specimen  of  Chokspus  didactylus  from  Mr.  Gerrard  of  London, 
kindly  aflForded  me  the  opportunity  of  studying  its  anatomy.  Notwith- 
standing the  peculiar  habits  of  this  animal,  it  does  not  seem  to  have 
received  much  attention  from  myologists.  The  fullest  description  is  that 
of  Professor  Humphry  (Journal  of  Anatomy  and  Physiology,  November, 
1869),  and  even  that  is  incomplete  in  many  points,  which,  however,  is 
easily  accounted  for  from  the  fact  of  many  of  the  muscles  having  become 
decomposed ;  Mr.  Galton,  in  his  Paper  on  Dasypus  (Transactions  of  the 
Linnean  Society,  XXYI.),  mentions  four  of  the  muscles,  and  Professor 
Meckel  is  stated  by  Professor  Humphry  to  have  alluded  to  the  muscular 
anatomy  of  this  animal,  but  I  have  not  been  able  to  corroborate  this.  With 
a  view  to  supply  this  defect  as  far  as  possible,  we  made  a  thorough  ex- 
amination of  our  specimen,  and  were  surprised  to  find  in  it  many  points 
of  difference  from  its  congener  Bradypus,  although   the  identity  of 

♦  Out  of  the  grant  of  money  given  to  him  by  the  Council  of  the  Koyal  Irish 
Academy  for  procuring  specimens  for  examination. 


Mackintosh — Muscular  Anatomy  of  Chokepua  didactylm,     67 

habits  of  the  two  creatures  led  us  to  expect  a  close  correspondence  in 
the  arrangement  of  their  muscles.  The  weights  of  roost  of  the  muscles 
are  given  in  decimals  of  an  ounce,  in  a  tahular  form  at  the  end  of  the 
Paper  {vide  p.  78). 

In  the  head,  we  noticed  the  Eustachian  tuhe  opening  as  an  ohlique 
pit  just  in  front  of  the  external  pterygoid,  and  placed  in  front  of  it  wjs 
a  distinct  depression  leading  upwards,  the  termination  of  which  we  en- 
deavoured to  find,  hut  in  vain,  and  hence  were  unahle  to  surmise  its- 
function.  The  mucous  memhrane  of  the  cheek  was  stndded  with 
rows  of  papillte ;  the  parotid  and  submaxillary  glands  were  united,  but 
no  trace  of  a  sublingual  existed.  Other  points  of  interest  in  general 
anatomy  were — the  well-developed  condition  of  the  stylomaxillary  fold 
of  fascia,  which  extended  along  the  whole  length  of  the  hyoid  arch  ; 
the  very  strong  spinoglenoid  ligament;  the  well- developed  condition  of 
the  ligaments  of  Flood  and  Humphry;  a  remarkable  fibrous  band, 
passing  from  the  front  aspect  of  the  humeral  trochanter  to  the  anterior 
ulnar  attachment  of  the  orbicular  ligament ;  the  very  deep  supra- 
decranal  pit  in  the  humerus;  the  limited  degree  of  rotation  of  the 
radius  (one-fifth  of  a  circle) ;  the  absence  of  the  round  ligament  of  the 
hip  joint,  as  is  usual  in  sloths  ;  the  strong  mucous  ligament  of  the  kne« 
joint ;  and  the  curious  arrangement  of  the  ligaments  in  the  ankle  joint. 
Of  these  the  external  lateral  extended  from  the  fibula  in  three  slips,  an 
anterior  attached  to  the  outer  tubercle  of  the  astragalus,  a  middle  at- 
tached to  the  body  of  that  bone,  and  »  posterior  to  the  calcaneum,  a 
deep  slip  of  which  dips  into  the  base  of  the  astragalus ;  a  large  number 
of  fibres  extend  between  these  two  bones  and  form  an  astragalo- 
calcanefd  ligament;  the  internal  lateral  is  strong  and  thick,  running 
from  the  inside  of  the  internal  malleolus  to  the  astragalus;  the  anterior 
ligament  is  weak. 
The  principal  muscles  of  the  head  were : — 

Massetericus  clothes  the  descending  process  of  the  jugal,  and  be- 
comes fused  near  its  insertion  with  temporalis,  which  was  normal. 

Buccinator  had  its  fibres  running  mainly  in  an  anterior  direction^ 

Zygomaticus  arises  fi-om  the  front  of  the  jugal  process. 
In  the  neck  and  trunk  we  found  the  following  arrangements  >— 

Splenius,  with  an  occipital  insertion,  has  its  origin  from  the  trans- 
verse processes  of  all  the  cervical  vertebrae,  and  from  the  front  of  com- 
plexus,  which  has  a  similar  cervical  origin,,  but  includes  the  first 
dorsal  also,  and  is  inserted  into  the  occiput. 

Longus  colli  is  remarkable  only  for  its  strength. 

Obliquus  colli  superior  arises  from  the  transverse  processes  of  the 
four  upper  cervical  vertebrse,  and  is  inserted  into  the  front  of  the  atlas, 
whilst  its  inferior  part  extends  from  the  first  three  dorsals  to  the  trans- 
verse process  of  the  seventh  cervical. 

Rectus  colli  stretches  from  the  second  and  third  dorsals  to  the 
atlas. 

Bectus  capitis  anticus  major  was  curiously  arranged,  taking  origin 


68  Proceedings  of  the  Royal  Irish  Academy. 

from  the  three  upper  dorsals  and  four  lower  cerricals,  and  being  in- 
serted into  the  basioccipital.* 

Ilectu3  capitis  anticus  minor  extended  from  the  transverse  process 
of  the  atlas  to  the  lateral  ridges  of  the  same  bone,  close  beside  the  in- 
sertion of  major. 

Rectus  capitis  posticus  major  and  minor  were  both  normal  in  their 
attachments,  but  feebly  developed,  the  latter  being  the  stronger  of  the 
two. 

Rectus  capitis  lateralis  was  moderately  strong. 

Obliquus  capitis  inferior  was  enormous,  a  condition,  probably,  to 
be  correlated  with  the  necessity  for  combined  lateral  and  downward 
motion  of  the  head.f 

Scalenus  medius,  with  scalenus  posticus  inseparable  from  it,  arises 
from  the  transverse  processes  of  all  the  cervictd  vertebrse  except  the 
atlas,  and  is  inserted  into  the  first  and  second  ribs,  some  of  the  fibres 
belonging  to  the  former  being  continuous  with  the  fibres  of  origin  of 
rectus  thoracicus  lateralis,  which  from  this  origin  passes  down  to  be 
inserted  into  the  eighth  and  ninth  ribs ;  it  is  placed  anteriorly  to  ser- 
ratus  magnus  and  externally  to  rectus  abdominis,  which  is  inserted 
into  the  fifth,  sixth,  seventh,  and  eighth  sternal  ribs,  and  has  its  fibres 
directed  upwards  and  slightly  outwards,  overlapping  the  normal  inter- 
nal intercostals. 

Sternocostalis  arises  from  the  presternum  and  four  upper  mesostemal 
steniebrsB,  and  is  inserted  into  the  second,  third,  fourth,  fifth,  and 
sixth  ribs. 

Iliocostalis  sends  a  tendon  to  every  rib,  and  has  a  cervical  prolonga- 
tion, as  has  longissimus  dorsi,  which  is  very  large. 

Serratus  posticus  inferior  arises  from  Uie  lumbar  fascia,  and  is  in- 
serted into  the  ribs,  from  the  thirteenth  to  the  twenty-third  inclusive. 
^  Stemomastoideus  and  deidomastoideus  are  curiously  related  to  one 
another ;  they  are  both  inserted  into  the  paramastoid  process,  separated 
only  by  the  spinal  accessory  nerve;  the  former  arises  from  the  an- 
terior surface  of  the  sternum,  and  from  the  mesoscapular  segment 
between  the  clavicle  and  the  sternum.  On  its  way  upward  it  detaches 
a  slip  from  its  hinder  border,  which  runs  into  the  deiodomastoid 
(origin  middle  of  clavicle),  which  in  turn  gives  off  a  slip  to  the  superior 
trapezius. 

Thus  it  will  be  seen  that  both  muscles  are  distiDctly  represented 
here,  the  only  trace  of  union  being  the  transverse  band.  In  Arctopi- 
thecus  a  single  muscle  exists  arising  from  the  sternum,  but  betraying  its 
compound  nature  by  its  two  slips  of  insertion  into  the  paramastoid;  in 
Bradypus  there  is  manifestly  a  sternocleidomastoid,  for  here  the  origin 

*  A  somewhat  similar,  but  more  restricted  origin  (sixth,  seventh,  and  eiglith 
cerWcals)  exists  in  Aretopitheeut  BlainviilH.  Vide  Proceedings  Royal  Irish  Aca- 
demy, Vol.  I.,  Series  II.  (Science),  page  619. 

t  This  muscle  was  also  well  developed  in  Arctopithecus  {loe.  eit.). 


Mackitttosh — MtMuiar  Anatomy  of  Cholcepm  didactylm,     69 

id  from  stemam,  first  rib,  and  clavicle.  Uafortuaately  this  muscle  was 
destroyed  in  Professor  Humphry's  specimen,  so  that  we  were  unable 
to  determine  whether  the  above  peculiarity  was  an  individual  or  a 
generic  one.  There  was  no  trace  of  the  slip  from  the  deidomastoid  to 
the  trapezius  in  either  Bradypus  or  Arctopithecus. 

Omohyoideus  was  absent,  and  trachelo-acromialis  (omo-atlanticus  of 
Professor  Haugbton),  though  it  shares  the  same  fate  in  Bradypus  and 
Arctopithecus,  is  represented  in  Choloepus  by  a  very  slender  band  of 
muscle  arising  from  the  paramastoid  process,  and  inserted,  not  into  the 
acromion  process  of  the  scapula,  but  into  the  fascia  over  the  supra- 
spinatus  muscle  in  front  of  the  insertion  of  the  occipital  rhomboid. 

Stemohyoideus  and  stemothyroideus  were  separate  from  one 
another  (as  in  Bradypus,  but  not  as  in  Arctopithecus),  the  former  aris- 
ing from  the  presternum  and  first  rib,  the  latter  from  the  presternum 
alone,  underneath  the  sternohyoid,  which  is  inserted  into  the  ten- 
dinous inscription  of  the  digastric  fusing  with  its  anterior  portion; 
the  sternothyroid  is  inserted  as  usual  into  the  side  of  the  thyroid  car- 
tilage. 

Diga^tricus,  which,  as  in  Arctopithecus,  only  merits  its  name  from 
the  tendinous  inscription  placed  opposite  the  angle  of  the  mandible, 
arises  from  the  stylohyal  bone  (tympanohyal  in  Arctopithecus),  and  is 
inserted  into  the  lower  jaw  as  usuaL 

Mylohyoideus  extends  along  the  whole  length  of  the  mandible.       ^ 
Geniohyoidcus  is  normal.  ~ 

Hyoglossus  runs  from  the  ceratohyal  and  thyrohyal  to  the  tongue,  • 
and  styloglossus  to  the  same  organ  from  the  former  of  those  two  bones. 
The  muscles  in  connexion  with  the  Fore  limb  were  arranged  as 
follows: — 

Trapezius  was  with  difficulty  separable  into  superior  and  inferior 
portions;  the  former,  which  included  the  clavicular  segment  as  well, 
arose  from  the  middle  line  of  the  neck  and  from  the  occiput,  and  was 
inserted  into  the  lower  border  of  the  scapular  spine  as  far  down  as  the 
origin  of  deltoid;  the  inferior  part  extended  from  the  four  upper  dorsal 
spines  to  the  spine  of  the  scapula. 

Khomboideus  is  divisible  into  three  parts,  (a)  major,  arising  from 
the  two  lower  cervical  and  three  upper  dorsal  vertebrae,  inserted  into 
the  whole  vertebral  edge  of  the  scapula,  and  completely  covering  the 
small  thin  (b)  minor,  which  extends  from  the  sixth  and  seventh  cervi- 
cal vertebrse  to  the  scapula  opposite  to  the  spine ;  (c)  occipital,  quite 
separate  from  the  other  two,  arising,  as  its  name  imports,  from  the 
occiput  and  inserted  into  the  superior  angle  of  the  shoulder  blade.* 

Teres  major  is  a  large  muscle  which  arises,  as  usual,  from  the  sca- 
pula, and  has  the  normal  humeral  insertion  separate  from,  but  close  to 
the  attachment  of  latissimus  dorsi,  which  has  an  extensive  origin  from 
the  spines  of  the  third,  fourth,  fifth,  sixth,  and  seventh  dorsal  vertebrae, 


*  This  portion  wu  absent  in  Arctopithecus  and  Bradypus. 


70  Proceedinya  of  the  Royal  Irish  Academy. 

from  the  eleventh,  twelfth,  and  thirteenth  ribs,  and  from  the  lumbar 
fascia. 

Teres  minor  is  inseparable  posteriorly  from  infraspinatus. 

Pectoralis  minor  is  not  represented,  but  its  absence  is  compensated 
for  by  pectoralis  major,  which  consists  of  three  parts ;  the  first  of  these 
arises  from  the  presternum^  and  is  inserted  into  the  pectoral  ridge, 
which  occupies  about  the  upper  two-fifths  of  the  humerus  ;  the  highest 
fibres  of  origin  are  the  lowest  fibres  of  insertion,  and  the  whole  hume- 
ral attachment  is  about  four  times  as  long  as  the  sternal ;  the  second, 
or  bicipital  part,  arising  from  half  an  inch  of  the  sternum  below  the 
last,  runs  parallel  to  it,  and  is  inserted  into  the  inner  border  of  the 
flexor  of  the  forearm,  opposite  the  level  of  the  supracondyloid  foramen; 
the  third  segment,  arising  from  the  whole  length  of  the  sternum,  is 
composed  of  two  laminae,  the  superior  being  inserted  underneath  the 
attachment  of  the  first  part,  and  equalling  it  in  length,  the  deeper  layer 
going  to  the  outer  part  of  the  head  of  the  humerus  and  to  the  capsule 
of  the  shoulder  joint,  with  the  anterior  thoracic  nerve  crossing  its 
upper  border  and  distributed  to  its  superior  aspect.  No  trace  of  this 
remarkable  arrangement  seems  to  exist,  either  in  Bradypus  or  Arcto- 
pithecus,  for  the  great  pectoral  in  both  is  merely  bilaminar,  not  even 
presenting  the  prestemo-humeral  slip,  though  in  the  latter  genus  the 
deep  lamina  of  the  third  part  sends  a  slip  to  the  capsule  of  the  shoulder 
joint.  It  will  be  interesting  to  know  if  the  curious  insertion  of  the 
second  part  be  constant  in  Choloepus ;  Professor  Humphry  was  not  able 
to  determine  its  arrangement  in  his  specimen. 

Pectoralis  quartus(brachio-lateralis.  Professor  Humphry)  arises  from 
the  eighth,  ninth,  tenth,  and  eleventh  ribs,  and  is  inserted  into  the 
head  of  the  humerus. 

Coracobrachialis  presented  both  the  long  and  short  varieties,  the 
former  arising  from  the  coracoid  process  and  being  inserted  into  the  in- 
ner edge  of  the  humerus,  behind  the  supracondyloid  nerve ;  the  latter; 
with  a  similar  origin,  is  inserted  into  the  humerus,  below  and  behind 
the  tendons  of  latissimus  dorsi  and  teres  major.  Mr.  Gal  ton  describes 
it  as  being  thin,  cord- like,  and  of  uniform  size,  but  does  not  say  to 
which  variety  it  belongs. 

Subclavius  extended  from  the  first  rib  to  the  inner  border  of  the 
sternal  end  of  the  clavicle  and  to  the  acromion  process,  as  was  also  the 
case  in  Mr.  Galton's  specimen. 

Deltoideus  is  divisible,  as  usual,  into  three  parts :  scapular,  acro- 
mial, and  clavicular;  the  first  and  largest  of  these  arises  from  the  spine 
of  the  scapula,  and  is  inserted  into  the  deltoidal  crest  on  the  humerus; 
the  second  part  arises  from  the  acromion  process  and  outer  border  of 
the  clavicle,  and  is  inserted  into  the  radius  along  with  the  superficial 
part  of  the  biceps;  the  third  has  a  similar  origin  to  the  second,  and  is 
inserted  along  with,  but  free  from,  the  first.  Here  again  we  have  a 
considerable  difference  ftova  the  arrangement  in  A'l,  where  the  muscle  is 
not  tripartite  at  all,  though  in  Arctopithecus  it  supplies  an  accessory 
head  to  the  biceps. 


'M.ACKWTOSH— Muscular  Anatomy  of  Cholcepua  didactylm.     71 

SupraspinatuB,  mfraspinatus,  and  Bubscapularia  presented  no  fea- 
tures of  interest,  except  that  the  weight  of  the  latter  equalled  the  com- 
bined weights  of  the  two  former ;  a  nearly  similar  condition  occurred 
in  Arctopithecus. 

Subscapulohumeralis  was  very  long  and  quite  distinct. 

Serratos  magnus,  which  had  no  separate  levator  scapulsB  portion, 
arose  from  the  upper  six  and  from  the  eighth  ribs,  as  weU  as  from  the 
three  lower  cervical  transverse  processes,  and  was  inserted  into  the 
scapula,  as  usual. 

Biceps  humeralis  is  a  curious  muscle,  but  by  no  means  so  complex 
as  in  Arctopithecus.  It  has  a  simple,  long  tendon  of  origin  f^om  the 
scapula,  which  expands  into  two  bellies,  the  superior  of  which  joins 
the  acromial  deltoid,  and  is  inserted  into  the  tubercle  of  the  radius,  as 
usual ;  the  deeper  segment  is  inserted  into  the  coronoid  process  of  the 
ulna,  along  with,  and  inseparable  from,  brachialis  anticus,  which  arises 
from  the  outer  aspect  of  the  humerus  external  to  the  insertion  of  the 
deltoid,  and  extending  half-way  up  the  bone.  This  arrangement 
appears  to  present  us  with  another  variety  in  the  already  numerous 
modifications  of  attachment  of  biceps  in  the  Edentata. 

Dorso-epitrochlearis  (Tricipiti  accessorius)  is  a  large  muscle  arising, 
as  usual,  f^m  triceps,  and  inserted  entirely  into  the  supracondyloid 
process.  Mr.  Galton  describes  it  as  being  thin,  cylindrical,  rolled  on 
itself,  and  inserted  chiefly  into  the  anterior  ridge  of  the  supracondyloid 
foramen,  but  slightly  into  the  humerus  above  the  foramen  and  below 
the  insertion  of  coracobrachialis ;  there  was  no  forearm  prolongation. 

Triceps  longus,  externus,  and  intemus,  are  all  norknal,  their  heads 
being  more  or  less  fused. 

Anconeus  externus  is  small,  and  can  only  be  artificially  separated 
from  triceps  longus,  and  anconeus  intemus  (epitrocles- anconeus)  is 
in  the  same  concdtion  with  regard  to  its  insertion,  though  quite  dis- 
tinct at  the  origin.  It  was  present  in  Mr.  Galton's  specimen,  but  is 
not  described. 

Pronator  radii  teres  had  a  similar  origin  in  our  specimen  and  in 
Professor  Humphry's,  viz.,  above  the  internal  condyle  of  the  humerus, 
but  the  insertions  differed  considerably.  Professor  Humphry  found  it 
to  be  attached  to  the  lower  end  of  the  radius  opposite  to  the  insertion 
of  supinator  longus,  whereas,  in  our  specimen  it  fused  with  the  lower 
part  of  that  muscle,  which  consists  of  two  parts — a  superficial  which 
arises  from  the  deltoid,  but  is  distinguished  from  it  by  a  tendinous 
inscription,  and  was  inserted  into  the  fascia  of  the  front  of  the  wrist, 
and  a  deep  segment  which  is  enormously  developed,  arising  from  the 
humerus  outside  the  musculospiral  ridge  and  extending  as  far  down  as 
the  condyle,  and  inserted  into  the  radius  for  the  lower  four- fifths  of  its 
length.  Professor  Humphry's  specimen  resembled  ours  in  being 
double,  in  the  insertion  of  the  superficial  portion,  and  the  origin  of  the 
deeper ;  he  describes  the  origin  of  the  former  part  as  being  high  up  on 
the  humerus,  not  from  the  deltoid,  whilst  the  insertion  of  the  deeper  seg- 
ment was  into  the  end  of  the  radius,  much  as  in  man ;  this  arrange- 


72  Proceedings  of  the  Royal  Irish  Academy. 

ment  agrees  more  closely  with  that  found  in  Arctopithecus  than  it  does 
with  the  condition  in  our  specimen. 

Pronator  quadratus  has  a  hroader  attachment  to  the  ulna  than  to 
the  radius,  the  reverse  apparently  obtaining  in  Professor  Humphrj^s 
specimen,  though  it  is  not  quite  clear  whether  his  description  refers  to 
Unau  or  to  Ai*. 

Flexor  carpi  radialis  extends  in  both  specimens  from  the  inner 
condyle  of  the  humerus  to  the  scaphoid  and  flexor  digitorum  profun- 
dus and  sublimiSf  and  palmaris  longus  presented  the  same  features  in 
the  two.  The  two  latter  muscles  are  fused  for  the  upper  part  of  their 
course,  but  near  the  distal  end  the  former  of  the  two  becomes  separate 
ai  a  small  muscle  ending  in  two  tendons  to  the  two  digits;  the  main 
part  of  the  muscle  ends  also  in  two  tendons  to  the  digits.  The  first 
named  of  the  three  is  quite  distinct,  arising  from  the  outer  condyle  of 
the  humerus,  from  the  forearm  bones,  and  from  the  tendons  of  the  radial 
and  ulnar  flexors  of  the  wrist,  as  well  as  from  the  tendon  of  palmaris ; 
it  also  sends  two  tendons  to  the  terminal  phalanges  of  the  digits. 

Flexor  pollicis  longus  was  not  represented  in  our  specimen,  and 
Professor  Humphry  makes  no  mention  of  it. 

Flexor  carpi  ulnaris  is  a  curious  muscle,  consisting  of  two  parts ; 
the  upper  one  of  these  arises  from  the  back  of  the  internal  condyle  and 
from  the  hinder  border  of  palmaris  (?),  becomes  tendinous  at  the  mid- 
dle of  the  forearm,  and  is  inserted  into  the  outer  border  of  the  radius 
posterior  to  and  confluent  with  the  insertion  of  supinator  longus,  and 
covering  over  the  attachment  of  extensor  carpi  radialis ;  it  is  also  in- 
serted into  the  fascia  of  the  back  of  the  forearm ;  the  deep  part,  which 
appears  to  be  the  normal  ulnar  flexor,  arises  from  the  olecranon,  from 
the  lower  border  of  anconeus,  and  from  the  whole  inner  edge  of  the 
ulna,  and  is  inserted  into  the  pisiform  bone.  Professor  Humphry  also 
describes  it  as  consisting  of  two  parts,  but  the  upper  one,  whilst  in  the 
main  agreeing  as  to  its  origin  with  the  foregoing  description,  becomes 
frised  with  supinator  longus,  and  is  inserted  into  the  palmar  fascia,  pisi- 
form, and  margin  of  the  ulna.*  The  deep  part  had  the  same  arrange- 
ment as  in  our  specimen.  The  separation  into  two  parts  of  this  muscle 
in  Cholcepus  is  foreshadowed  in  the  Three-toed  Sloth,  where  the  origin 
is  bicipitcd  and  the  two  parts  remain  separate  for  a  long  distance,  but 
there  is  no  tendency  to  union  between  it  and  supinator  longus. 

Supinator  brevis  is  large,  inserted  into  the  upper  one- third  of  the 
radius,  and  pierced  by  the  posterior  interosseous  nerve,  which  forms 
much  the  larger  part  of  the  radial  nerve. 

Extensor  carpi  radialis  is  single,  arising  from  the  outer  humeral 
condyle  and  from  the  radius,  and  ending  in  two  tendons,  one  being  at- 
tached to  the  upper  two-thirds  of  the  second  metacarpal  bone,  and  the 
other  to  the  proximal  end  of  the  third  metacarpal.    Professor  Humphry 


*  It  is  possible  that  this  may  be  a  clerical  error,  as  the  ulnar  attachment  of  sup. 
long,  ia  not  mentioned  by  Professor  Humphry. 


Mackintosh — Muscular  A  natomy  of  Choloepus  didadylus,      73 

only  foand  the  condylar  origin,  and  the  insertions  of  hoth  tendons  was 
into  the  proximal  parts  of  the  metacarpals. 

Extensor  digitorum  longns  presented  no  feature  of  interest,  extend- 
ing from  the  outer  condyle  and  from  the  ridge  on  the  back  of  the 
radius  to  the  terminal  phalanges  of  the  digits.  The  radial  origin  is  not 
mentioned  by  Professor  Humphry. 

Extensor  minimi  digiti  (auricularis)  arises  from  the  intermuscular 
septum  on  the  back  of  the  forearm^  being  traceable  as  far  as  the  upper 
third ;  the  tendon  runs  through  a  separate  sheath  in  the  annular  liga- 
ment, expands  on  the  ulnar  side  of  the  third  digit,  and  joins  the  ten- 
don of  the  long  flexor.  This  muscle  is  not  described  by  Professor 
Humphry. 

Extensor  carpi  ulnaris  arose  in  both  specimens  from  the  external 
condyle,  olecranon  and  ulna,  and  divided  into  two  parts,  one  of  which 
becomes  tendinoas  and  is  inserted  into  the  proximal  dorsal  aspect 
of  the  first  phalanx  of  the  third  digit;  the  second  segment,  which  is  in 
fact  an  ulnaris  quinti,  ends  in  a  tendon  which  joins  that  of  the  extensor 
of  the  little  finger  at  its  insertion.  In  Professor  Humphry's  specimen 
the  muscle  ended  in  two  tendons  running  to  the  third  and  fourth 
digits. 

Extensor  ossis  metacarpi  pollicis  (extensor  pollicis  primus)  arose 
in  both  from  the  greater  part  of  the  posterior  surface  of  the  ulna,  and 
was  inserted  into  the  trapezium. 

Extensor  secundi  intemodii  pollicis  was  absent. 
Extensor  indicis  was  normal,  running  in  both  animals  from  the 
middle  of  the  ulna  to  the  rudimentary  second  digit. 

Interossei  are  arranged  somewhat  similarly  in  both.  In  our  spe- 
cimen the  first  and  second  act  as  abductor  and  adductor  annularis,  re- 
spectively; the  third  placed  between  the  third  and  fourth  metacarpals 
runs  to  medius;  the  fourth  and  fifth  between  the  second  and  third  me- 
tacarpals go  to  medius  and  index,  respectively ;  the  sixth,  which  is 
.  bicipital  and  placed  between  the  first  and  second  metacarpals,  goes  to 
index,  whilst  an  additional  one,  which  does  not  seem  to  have  existed 
in  Professor  Humphry's  specimen,  extended  fi-om  the  pisiform  bone 
to  the  ulnar  side  of  the  second  metacarpal.* 

Lumbricalis  single,  arising  between  the  tendons  of  flexor  di- 
gitoruip,  divides  into  two  parts,  one  going  to  the  radial  and  one 
to  the  ulnar  side  of  each  digit,  the  latter  attachment  apparently  not 
existing  in  Professor  Humphry's  specimen. 

We  found  a  tendinous  band  passing  from  the  tip  of  the  rudimen- 
tary fifth  digit  to  the  first  phalanx  of  the  fourth. 

♦  Professor  Humphry  arranges  them  thus : — One  between  Met.  1.  &  II.  to  the 
radial  side  of  the  extensor  tendon  of  digit  II. ;  one  between  Met.  IV.  &  III.  to 
ulnar  side  of  extensor  tendon  of  digit  III. ;  one  between  Met.  II.  &  III.  on  palmar 
aspect  passing  to  ulnar  side  of  extensor  tendon  of  digit  II. ;  and  one  on  the  dorsal 
aspect  to  the  radial  side  of  the  extensor  tendon  of  digit  III.  There  is  also  an  ad- 
ductor of  digit  II.  from  pisiform  to  ulnar  side  of  first  phalanx  (which  seems  to 
represent  the  "  additional' *  muscle  mentioned  above).  There  is  also  a  second  set 
of  *^  phalangeal"  interossei,  two  in  number,  from  the  apposed  sides  of  the  two 
second  phalanges  to  the  apposed  sides  of  the  two  extensor  tendons. 

R.  1.  A.  PliOC,  SER.  II.  VOL.  IT.,  KCIKXCI:.  L 


74  Proceedings  of  the  Royal  Irish  Academy. 

In  the  hind  limb : — 

Sartorius  consists  of  two  parts,  primus  and  secundus;  the 
former  arises  from  the  anterior  superior  spine  of  the  ilium,  and  by  a 
few  fibres  from  the  abdominal  parietes,  and  is  inserted  into  the 
inner  side  of  the  femur  for  the  third  one-fourth  of  its  length ;  it  is  sup- 
plied by  the  external  cutaneous  nerve  of  the  lumbar  plexus.  Secundus 
arises  from  the  middle  of  Poupart's  ligament  and  from  the  abdominal 
wall,  and  runs  to  the  upper  point  of  quadrisection  of  the  tibia.  This 
latter  portion  was  not  found  at  all  by  Professor  Humphry,  though  his 
description  of  the  former  division  agrees  closely  with  the  above  arrange- 
ment. In  BradypuB  and  Arctopithecus  there  is  but  a  single  origin, 
which,  however,  takes  in  both  the  parts  above  mentioned  (ilium  and 
Poupart's  ligament),  but  the  insertion  is  double,  into  femur  and  tibia, 
though  the  latter  insertion  did  not  exist  in  Professor  Macalister's 
specimen. 

Psoas  parvus  presents  nothing  remarkable,  arising  from  the  five 
lower  dorsal  vertebrae,  and  being  inserted  into  the  pectineal  tubercle. 

Psoas  magnus  is  separable  with  difficulty  from  the  normal  Iliacus, 
and  has  a  coextensive  origin  with  psoas  parvus. 

Pectineus  stretches  from  the  pectineal  tubercle  to  the  upper  half  of 
the  femur.  The  arrangements  in  Professor  Humphry's  specimen  are 
substantially  the  same  as  these. 

The  three  adductors  are  also  normal  and  correspondingly  arranged, 
primus  being  quite  separate,  secundus  not  divisible  into  two  laminee,  and 
inserted  into  the  middle  of  the  femur,  and  tertius,  extending  from  the 
horizontal  ramus  of  the  pubis  to  the  lower  point  of  trisection  of  the 
femur,  or  to  the  condyle,  as  in  Professor  Humphry's  specimen. 

Quadratus  femoris  is  normal,  agitator  caudse  absent,  as  is  the  case 
also  with  obturator  internus,  but  its  non-appearance  is  compensated 
for  by  obturator  extemus,  which  consists  of  two  parts,  the  upper  aris- 
ing from  the  horizontal  ramus  of  the  pubis  near  the  acetabulum,  the 
lower,  which  is  penniform,  taking  origin  from  the  whole  obturator  mem- 
brane, and  both  the  inside  and  outside  of  the  horizontal  ramus  of  the 
pubis. 

The  gemelli  are  present  and  distinct.*  Glutaeus  maximus  is  a  fan- 
shaped  muscle  arising  from  the  fascia  over  the  side  of  the  sacrum  and 
of  glutseus  mediuB,  and  from  the  tuber  ischii ;  it  is  inserted  half  way 
down  the  outside  of  the  femur. 

Pyriformis  is  very  separate,  arising  from  the  front  of  the  sacrum 
inside  the  pelvis,  and  inserted  into  the  great  trochanter,  frised  with 
that  of  glutSBUB  mediuB,  which  arises  as  usual  from  the  iliac  fossa,  and 
is  overlapped  by  glntsBus  quartus  both  at  origin  and  insertion. 

GlutseuB  minimus  exists  as  a  very  fine  band  crossing  the  back  of 
the  capsule  of  the  hip  joint,  from  the  margin  of  the  acetabulum  to 
the  great  trochanter,    underneath  pyriformis.      Gluteeus  quintus    is 

•  There  wm  a  double  obturator  cztemus  in  Arctopithecus,  but  a  single  one  in 
Bradypus. 


Mackintosh — Muscular  Atiatoniy  of  Cholcppus  dicUidylus,     75 

absent  as  is  tensor  vaginsB  femoris,  but  iliocapsularis  is  present  as  a 
small  mascle,  extending  from  the  anterior  inferior  spine  of  the  ilium 
to  the  capsule  of  the  joint.  None  of  these  muscles  are  alluded  to  by 
Professor  Humphry. 

Biceps  femoris  agrees  with  what  appears  to  be  its  general  condition 
among  Edentata,  in  consisting  of  two  parts,  one,  representing  the  nor- 
mal muscle,  arising  from  the  tuber  ischii  and  inserted  into  the  head  of 
the  fibula,  and  upper  third  of  the  tibia,  the  other  taking  origin  from 
the  whole  length  of  the  femur,  and  inserted  into  the  second  and  third 
fourths  of  the^inner  edge  of  the  tibia.  Professor  Humphry  found  some 
fibres  running  from  the  latter  portion  to  join  semitendinosus  and 
gracilis,  while  the  rest  of  it  formed  a  sheath  for  the  calf  of  the  leg,  and 
was  inserted  into  the  edges  of  the  two  bones  of  the  fore  leg,  a  condition 
which  approaches  very  closely  to  that  obtaining  in  our  specimen,  as  is 
shown  in  Plate  4,*  which  represents  more  particularly  the  relations 
of  biceps  to  the  double  insertion  of  gracilis  ;  the  pannicle  is  also  well 
seen  running  in  behind  the  origin  of  iliacus. 

Bicipti  accessorius  is  absent. 

Semimembranosus  is  large,  running  from  the  whole  internal  border  of 
the  tuber  ischii  to  be  inserted  into  the  tibia,  above  the  attachment  of 
semitendinosus,  which  has  no  inscription  (as  was  also  the  case  in  Pro- 
fessor Humphry's  specimen),  arises  along  with  the  ischial  portion  of 
biceps,  and  is  inserted  along  with  the  inner  half  of  gracilis,  which  con- 
sists of  two  parts  arising  in  common  from  the  symphysis  pubis ;  the 
•xtemal  portion  is  inserted  into  the  internal  aspect  of  the  tibia ;  the 
second  joins  the  ischial  biceps,  and  is  inserted  into  the  fibula  and  fibular 
fascia,  connected  also  with  semitendinosus.,  In  Arctopithecus  this 
muscle  is  single,  but  the  insertion  embraces  all  the  parts  described 
aboye ;  in  the  specimen  of  Bradypus,  dissected  by  Dr.  Macalister,  it 
was  also  single,  but  the  insertion  was  only  into  the  tibial  condyle, 
whilst  in  the  Ai,  examined  by  Professor  Humphry,  the  main  details 
corresponded  to  the  arrangement  in  Unau.  A  considerable  degree  of 
coalescence  obtains  in  quadriceps  extensor  cruris  rectus,  being  but 
slightly  separable  from  the  two  vast!  and  cruraeus,  which  are  completely 
fused. 

Popliteus  is  normal  with  a  lai^e  fabella  in  its  tendon  of  origin, 
with  which  in  Professor  Humphry's  specimen  soleus  is  connected  by 
a  thin  muscular  slip,  the  rest  of  the  muscle  arising  from  the  upper  part 
of  the  fibula ;  we  could  not  find  any  trace  of  the  former  head,  and  the 
latter  extended  over  the  whole  fibula  ;  the  insertion  in  both  was  into 
the  calcaneum. 

Gastrocnemius  extemus  arises  rather  higher  up  than  usual,  has  no 
fabella,  and  is  inserted  by  two  (?)  tendons  into  the  calcaneum ;  its  ten- 
don is  crossed  by  that  of  gastrocnemius  internus  at  the  lowest  point  of 

*  Which  is  a  camera  ludda  copy  of  Professor  Macalister' s  ad  naturatn  sketch. 
Similar  arnuigementa  exist  in  Arctopithecus,  Bradypus,  Manis,  Cyclothurus,  Myrme- 
cophaga,  Tamandua. 


76  Proceedings  oj  the  Eoyal  Irish  Academy, 

quinquoFcction  of  the  log,  the  latter  tendon  going  to  be  inserted  into 
the  08  calcis  external  to  the  former,  and  quite  separate  from  it ;  the 
origin  of  intemus  is  from  the  lower  back  portion  of  the  femur  and  is 
devoid  of  a  fabella.  A  similar  arrangement  is  described  by  Professor 
Humphry,  with  the  exception  of  the  two  tendons  of  insertion  of 
extemuB. 

Plantaris  is  not  represented  in  either^  though  Professor  Humphry, 
judging  by  the  arrangement  in  Cy cloth urus,  seems  to  think  that  it  is 
involved  in  gastrocnemius  eztemus,  and  regards  the  popliteal  slip  of 
Boleus  as  correspoding  to  the  external  portion  of  the  gastrocnemius  in 
Cyclothurus.     It. was  largely  developed  in  Arctopithecus, 

F]exor  digitorum  longus  and  Flexor  hallucis  longus  are  fused,  but 
divide  into  three  tendons  before  reaching  the  ankle  joint ;  one  tendon 
goes  to  each  digit  and  receives  the  tendon  of  the  combined  tibialis 
antiouB  and  extensor  longus.  Professor  Humphry  in  his  description  of 
flexor  digitorum  says  that  it  arises  from  the  tibia,  fibula,  and  slightly 
from  the  popliteal  sesamoid,  the  tibial  portion  being  deep  and  covered 
by  the  fibular  part,  as  well  aa  by  tibialis  posticus ;  the  former  of  these 
represents  the  flexor  of  the  fingers  and  the  latter  that  of  the  thumb. 
The  arrangement  is  more  complex  in  Arctopithecus^  where  we  find  fiexor 
digitorum  existing  as  a  tricipital  muscle  taking  origin  from  the  upper 
and  back  part  of  the  tibia,  from  the  middle  of  that  bone,  and  from  the 
greater  part  of  the  fibula  and  external  lateral  ligament  of  the  knee,  and 
receiving  the  tendon  of  plantaris ;  flexor  hallucis  arises  from  the  fibula 
and  interosseous  membrane,  and  unites  with  it,  the  two  subsequently 
dividing  into  three  tendons.  The  first  of  these  origins  of  flexor  digitorum 
is  alone  described  by  Professor  Macalister  in  Bradypus,  and  Dr. 
Humphry  found  in  that  animal  that  it  consisted  of  three  parts  repre- 
senting respectively  plantaris,  flexor  digitorum,  and  flexor  hallucis. 

Flexor  digitorum  brevis  arises  from  the  calcaneum,  and  is  inserted 
into  the  sheath  of  the  flexor  tendon  of  the  middle  digit.  Professor 
Humphry  found  a  totally  dificrent  arrangement,  for  this  muscle  in 
his  specimen  was  in  three  parts,  one  bicipital  from  entocuneiform  and 
08  calcis,  the  other  two  from  os  calcis;  they  all  terminate  in  the 
sheaths  of  the  flexor  tendons. 

Flexori  longo  accessorius  is  very  large,  arising  from  both  sides  of 
the  calcaneum  and  inserted  chiefly  into  the  tendon  of  the  outer  toe  ; 
it  was  continuous  with  soleus  in  Professor  Humphry's  specimen. 

Tibialis  posticus  is  arranged  quite  differently  in  the  two  specimens. 
In  ours  it  was  perfectly  normal,  extending  from  the  tibia  to  the 
entocuneiform  ;  in  Dr.  Humphry's  it  consisted  of  two  parts,  the  ten- 
don of  the  larger  of  which  runs  behind  the  inner  malleolus,  sends  a  few 
fibres  to  the  entocuneiform,  but  is  mainly  attached  to  the  second  meta- 
carpal ;  the  tendon  of  the  Bmaller  internal  portion  runs  in  a  separata 
channel  in  the  malleolus,  and  passing  over  the  inner  cuneiform,  becomes 
eontinuous  with  a  portion  of  the  short  flexor  of  the  fingers,  whose  ten- 
don blends  with  that  of  flexor  biwis  to  the  fourth  digit.  The  arrange- 
ment in  Ai  agrees  in  the  main  with  that  in  our  specimen.     Tibialis 


Mackintosh — Muscular  Anatomy  of  Chohepus  didactylus,     77 

anticus  and  extensor  hallucis  occupy  a  very  curious  position ;  their 
origins,  which  are  slightly  separable  from  one  another,  extend  down  the 
whole  front  of  the  tibia,  and  the  lower  two-thirds  of  the  anterior  bor- 
der of  the  fibula,  and  becoming  perfectly  fused  in  front  of  the  leg;  the 
tendon  formed  by  the  two  bellies  winds  round  the  ankle  joint  and  is 
inserted  into  the  front  of  the  flexor  of  the  middle  toe,  thus  converting 
these  two  powerful  muscles  into  flexors.  Here  again  Dr.  Humphry's 
description,  so  far  at  least  as  the  origin  is  concerned,  diflers  largely 
from  ours.  He  found  the  former  of  the  two  to  consist  of  three  parts, 
one  arising  from  the  upper  half  of  the  tibia,  one  from  the  middle  of  the 
fibula  (extensor  hallucis),  and  a  third  from  the  lower  front  part  of  the 
fibula  and  from  the  malleolus  ;  this  latter  crosses  the  ankle  to  be  in- 
serted into  the  entocuneiform  bone'  and  base  of  first  metatarsal,  but 
apparently  quite  separate  from  the  rest  of  the  muscle,  whose  two  parts 
unite  into  a  tendon  which  subsequently  divides  into  three  going  to  the 
flexor  tendons  of  the  three  digits ;  the  two  latter  segments  appear  to 
represent  in  their  origins  the  entire  fibular  part  in  our  specimen,  but 
we  found  no  trace  of  the  curious  insertion  of  the  third  portion,  nor  yet 
of  the  threefold  attachment  of  the  tendon  from  the  first  and  second. 
The  tricipital  origin  also  obtains  in  Arctopithecus  and  Bradypus,  but 
the  insertion  is  into  the  entocuneiform  and  metatarsals. 

Extensor  hallucis  brevis  is  a  small  muscle  extending  from  the 
lowest  one-tenth  of  the  fibula  to  the  rudimental  hallux. 

Extensor  digitorum  brevis  arises  from  the  front  of  the  tarsal 
bones,  and  its  three  tendons  are  inserted  into  the  deep  surfaces  of  the 
tendons  of  extensor  longus.  The  origin  in  Professor  Humphrj-'s 
specimen  included  the  proximal  parts  of  the  metatarsals,  as  well  as  the 
tarsals;  the  insertion  was  into  the  terminal  phalanges  of  all  the  digits. 
Transversalis  pedis  extended  from  the  external  metatarsal  to  the 
base  of  the  first  phalanx  of  the  inner  toe,  to  which  Dr.  Humphry  adds 
a  second  insertion  into  the  distal  end  of  the  first  metatarsal. 

Extensor  digitorum  longus  is  a  small  muscle  sending  one  teiidon 
to  each  of  the  three  digits ;  it  supplied  only  the  third  and  fourth  digits 
in  Professor  Humphry's  specimen. 

PeronsBUs  longus  arises  from  the  back  of  the  fibula,  and  from  the 
popliteal  sesamoid  in  our  specimen,  and  is  inserted  into  the  base  of  the 
fourth  metatarsal,  with  slight  attachments  to  the  other  three ; 
peronaus  quinti  was  absent,  and  we  could  find  no  trace  of  p.  brevis, 
though  it  is  described  by  Professor  Humphry  as  extending  from  the 
malleolus  to  the  base  of  the  fifth  metatarsal;  p.  tertius  is  well  deve- 
loped in  both,  running  from  the  front  edge  of  the  fibula  to  the  fifth 
metatarsal,  with  fibres  to  the  fourth,  as  well  as  in  Professor  Humphry's 
specimen. 

Abductor  interni  digitiin  our  specimen  stretches  from  the  internal 
plantar  sesamoid  to  the  sheath  of  the  flexor  tendon  of  the  inner  digit. 

The  interoBsei  are  well  developed,  but  present  no  modification  of 
any  great  importance,  two  being  attached  to  each  extensor,  one  on 
each  side. 


78 


Proceedings  of  the  Royctl  Irish  Academy. 


Table  of  Weights  of  Musclei  of  Chohpus  didactylus. 


Hbap  and  Trunk. 

MassetericoB)  3.O5 

Temporalis    J 

Digaatricua 0-09 

Spleniua 0-06 

Sternomaatoideua 0  08 

Cleidomastoideua 0.05 

Tracheloacromialia 002 

Stemohyoideua 0  09 

Stemothypoideua 004 

FoBB  Limb. 

TrapcBiua  inferior 0*09 

Trapezius  clayioularis  \  .  .  ,  o*20 
Trapezius  superior         j  .     .     .     • 

Rhomboideos  major 0*13 

Rhomboideus  minor 0*03 

Bhomboideus  occipitalis    .    .     .    .0*03 

Teres  major 0*13 

Latissimus  dorsi 1'24 

Teres  minor 3*06 

/  prestemohumeral  not  weighed 

Pectoralis  1  bicipital  slip  .    .     .     .  012 

major     j  superficial  3rd  part .     .  0*61 

V  deep  3rd  part.  .  .  .  0*23 
Coracobrachialis  longus  ....  0*02 
Coracobrachialis  brevis     .     .     .     .0*01 

Subclayius not  weighed 

Deltoideua  acromialis 0*20 

Deltoideus  scapularis 0  26 

Deltoideus  claTicularis     .    .     .     .  0  03 

Supraspinatus 0*19 

Infraspinatus 0*12 

Subscapularis 0*31 

Subscapulohumeralis  .....  0*07 
Serratus  magnus,  superficial .     .     .0*38 

Serratusmagnus,  deep 0*11 

Biceps  bracMi 0*08 

Brachialis  anticuB 0*10 

DorsoepitrochleariB 0*16 

Triceps  longus 020 

Triceps  intemns  )  ^.^m 

Triceps  ezternus ) 

Anconeus  extemus 0*02 

Anconeus  intemus 0.03 

Pronator  teres 0-17 

Supinator  longus,  deep  ....  0*42 
Supinator  longus,  superficial      .     .0-05 

Pronator  quadratus 0*05 

Flexor  carpi  radialis 0*05 

Flexor  digitorum  profundus  .  .  .  0-75 
Flexor  digitorum  sublimis  .  .  .  0  02 
Polmaris  longus Q'\2 


Flexor  carpi  ulnaris 0  06 

Supinator  brevis 0-0» 

Extensor  carpi  radialis     ....  0*09 

Extensor  digitorum  longus    .     .     .0*07 

Extensor  minimi  digiti     .     .     .     .0*05 

Extensor  carpi  ulnaris 0*09 

Extensor  ossis  metacarpi  poUiois    .  0*01 

Extensor  indicis 0*03 

HiKD  Limb. 

Sartorius  primus 0*26 

Sartorius  secundus 0*09 

Psoas  parvus 013 

Psoas  magnus 0*24 

Iliacus 0-44 

Pectineus  .     .     .    <. 0*10 

Adductor  primus 0*18 

Adductor  secundus 0*17 

Adductor  tertius 0-17 

Quadratus  femoris 0*04 

Obturator  extemus 0*23 

Gemelli 0*04 

Gluteus  maximus    .    ,     .     .     .     .0*41 

Gluteus  medius 0*27 

Gluteus  quartus 0*10 

Gluteus  minimus     ...    not  weighed 

Pyriformis 0*11 

lUocapsularis 0*01 

«.  ^  .* ')  ischiatic  part    .     .0*17 

Bicepsfemon*|^^^^^p^^  ^.^l 

Semimembranosus 0*28 

Semitendinoeus 0*08 

P,.  -I...  I  inner  part 0*18 

Gracilis  }^^^^^^ 0*20 

Boctus  femoris 0*23 

Vastus  extemus  \ 

Vastus  intemus  > 0*26 

Crurseus  ) 

Popliteus 0*07 

Solsus 014 

Gastrocnemius  extemus  .  .  .  .0*08 
Gastrocnemius  intemus  .  .  .  .0*19 
Flexor  digitorum  longus)  ^  . « 

Flexor  haUucis  >      *     '     *     ^^ 

Flexor  digitomm  brevis  .  not  weighed 
Flexori  longo  accessorius ....  0*08 

Tibialis  posticus 0*07 

Tibialis  anticus  )'  q.^o 

Extensor  hallucis  longus  |         *     ' 
Extensor  hallucis  brevis  .     .     .     .0.05 
Extensor  digitomm  longus   .     .     .  0*08 
Extensor  digitorum  brevis    .     .     .  0*08 
Transversalis  pedis .    .     .    not  weighed 

Pcroneus  longus 0*06 

Peroneus  tertius 0-09 


Leeper — On  Retro-peritoneal  Cavities, 


XIII. — On  Eetso-pebitonxal  Cavities.  By  Georos  Eeginalb  Lsepeb, 
Student  in  Medicine,  Trinity  College,  I)ublin.    with  Plate  5. 

[Read  14th  December,  1874.] 

The  subject  of  retro-peritoneal  pouches  when  taken  in  connexion 
with  the  occurrence  in  them  of  intra-abdominal  hendae  is  a  yery  in- 
teresting one,  especially  as  so  few  of  these  fossae  exist.  Only  three 
such  cavities  have  as  yet  been  described,  which  are  as  follow : — 

1°.  The  "Fossa  Duodeno-Jejunalis"  on  the  left  side  of  the  3rd 
lumbar  vertebra. — This  fossa  has  been  fully  described  by  Huschke,* 
and  has  been  found  the  seat  of  an  intra-peritoneal  hernia  by  Treitz,t 
Chiene4  Peacock,  §  and  Gruber.jj 

2'.  The  ''Becessus  Ileo  Coecalii"  (fig  1). — This  concavity  is  very 
constant  and  is  frequently  a  deeply-excavated  hollow.  It  may  be 
from  0-25  of  an  inch  to  1*25  inches  in  depth,  and  may  be  seen  lying 
between  the  mesenteriolum  of  the  vermiform  appendix,  the  plica,  ileo- 
coecalis,  and  the  ccecum.  This  fossa  has  been  described  hj  Professor 
Luschka  of  Tubingen^  ;  it  may  (not.unfrequently)  contain  a  cyst.** 
Hernia  has  been  found  herein  by  Engel.ft 

3^  The  "  Subccecal  Eossa"  figured  in  the  sketch  (fig.  2)  has  been 
described  by  Luschka.]:^  No  example  of  hernia  has  as  yet  been  de- 
scribed as  occurring  in  this  fossa,  as  its  mouth  is  always  very  wide  in 
proportion  to  its  depth.  It  only  exists  when  the  mesocoecum  is  im- 
perfect. 

Through  the  kindness  of  Dr.  Macalister,  who  pointed  it  out  to  me,  I 
now  bring  forward  another  as  yet  undescribed  form  of  these  retro- 
peritoneal fosssB  which  came  under  my  observation  on  the  16th  of  No- 
vember last  in  the  Trinity  College  Dissecting  Eoom. 

On  opening  into  the  abdominal  cavity  of  a  man  of  about  55  years 
of  age,  in  the  right  iliac  fossa,  an  abnormal  fold  of  iliac  fascia  was  dis- 
covered bounding  a  sac  or  pouch  of  moderate  size.  It  consisted  of  a 
thin,  strong  semi-transparent  arch  extending  outwards  from  the  bor- 
der of  the  psoas  magnus  muscle  to  the  crest  of  the  Ilium,  part  of  the 

•  Lehre  von  den  Eingeweiden  des  Menschlischen  Korpers.  Leipzig,  1844, 
p.  3)6. 

t  Hernia  retro-peiitonealiB.  £in  Beitrag  zur  Geschichte  innerer  Hernier 
Prag,  1867. 

1  Journal  of  Anatomy  and  Physiology,  2nd  Series,  No.  2,  1868,  p.  218. 
f  Trans:  Pathological  Society  of  London,  YoL  2.,  page  60. 
jl  St  Petersburges  Med.  Zeitschrift,  1831,  Bd.  1. 

H  Ueber  die  peritonseale  nmhiillung  des  Blinddarmes  nnd  iiber  die  fossa  ileo- 
coBcahs.  Yirchow's  Arcliiy,  Vol.  21,  1861.  s.  286.    This  sac  is  really  a  portion  of  the 
visceral,  and  not  of  the  parietal  peritoneum. 
♦♦  Schott,  Wiener  Wochenbktt,  No.  44,  1862. 
ft  Wiener  Med.  Wochenachrift,  1861,  No.  10. 
{t  I)io  Anatomie  des  Menscblischen  Bauches,  s.  164. 


80  Proceedings  of  the  Royal  Iriah  Academy. 

fascia  covering  the  muscle  ;  the  mouth  of  the  sac  or  fossa  thus  fonucd 
looked  upwards  towards  the  coecum. 

The  peritoneum  lay  on  the  fascia,  to  which  it  was  only  loosely  con- 
nected, and  was  easily  separable  from  it,  but  part  of  it  was  involuted 
and  tucked  into  the  fundus  of  the  sac.  The  subserous  tissue  was  lax 
and  could  be  separated  without  difficulty. 

The  measurements  of  the  fascial  fold  were  as  follow : — 
Its  crescentic  free  border  arose  from  the  fascia  over  the  psoas  at  a 
part  3^  inches  above  Poupart's  Ligament. 

The  measurement  across  from  the  border  of  the  psoas  magnus  to 
the  crest  of  the  ilium  was  2*7  inches. 

Its  attachment  extended  3^  inches  behind  the  anterior  superior 
spine  of  the  ilium. 

The  sac  itself  was  *7  of  an  inch  in  depth. 

The  fascia  was  quite  free  from  the  tendon  of  the  psoas  parvus, 
which  was  inserted  as  usual.  A  branch  of  the  anterior  crural  nerve 
lay  on  the  margin  of  the  fascial  fold  forming  its  superficial  edge. 

The  coecum  had  not  descended  nearly  as  far  as  usual,  but  lay  loose 
in  the  right  lumbar  region,  attached  by  a  mesocoscum  four  inches 
broad,  and  which  was  continuous  with  the  mesentery.  The  vermiform 
appendix  lay  within  this  mesocoecum,  posterior  and  inferior  to  the 
coecum,  and  with  no  trace  of  a  mesenteriolum ;  it  was  moderately  long 
and  bent  on  itself  at  the  lower  end.  There  was  no  nerve  on  the  free 
edge  of  the  smaller  left  ''Fossa  retro-sigmoidalis.''  There  was  a 
cicatrix-like  mark  on  the  left  side  below  the  peculiar  fold,  but  no 
sign  of  inflammation. 

This  sac  which  we  are  considering  may  be  called  the  "  Ketro- 
coecal  Recessus;"  it  might  easily  become  the  seat  of  an  hernia,  and, 
therefore,  is  of  some  importance.  It  differs  from  the  sac  described  by 
Luschka  in  that  the  opening  of  the  fossa  described  by  him  looked  down- 
wards, whereas  that  before  us  looked  upwards. 

This  abnormality  is  remarkable  from  the  fact  of  its  not  having 
b«en  described  before.     It  may,  therefore,  fairly  be  considered  unique. 


TicnBOKSZ-—Laboratori/  Notes.  81 


Xiy. — ^Labokatobt  Notes.*    By  Charlm  R.  0.  Tichbobks,  Ph.  D., 

F.  C.  S.,  ^c. 

[Bead  December  14, 1874.] 

3. — On  the  Solution  of  Allocs  and  Metals  hy  Acids, 
SATnre  to  form  a  nnmber  of  estimations  of  tin,  in  alloys  of  tin  and 
lead,  I  found  it  necessary  to  effect  solution  of  the  mixed  metals  in 
Hydrochloric  Acid»  and  to  devise  a  quick  and  expeditious  method  of 
bringing  this  about  without  loss  of  substance.  The  alloys  were  dissolved 
in  the  ordinary  manner  and  according  to  the  usages  of  laboratory 
experience,  that  is  to  say — in  each  case  a  weighed  quantity  of  the 
alloy  was  coarsely  rasped  by  a  clean  plumber^s  file,  and  placed  into 
a  rather  capacious  flask,  with  the  necessary  quantity  of  pure  Hydro- 
chloric Acid ;  an  Indian-rubber  stopper  was  inserted,  through  which 
passed  a  short  tube.  The  flask  was  placed  upon  a  sand  bath  at  an 
angle  of  about  45  degrees,  so  that  no  loss  from  spitting  could  take  place 
up  the  neck.  Platinum  was  introduced  for  the  purpose  of  making  an 
energetic  voltaic  circuit  and  to  assist  the  solution.  The  action  with 
the  alloy  itself  is  energetic  enough  at  first,  but  it  gradually  subsides  and 
becomes  languid  after  the  Hydrochloric  Acid  has  become  in  any  degree 
saturated.  If  the  platinum,  however^  be  introduced^  this  sluggishness 
18  avoided.  From  the  nature  of  the  experiment  time  was  an  object  of 
considerable  importance,  and  yet  a  great  excess  of  acid  was  not 
desirable.  The  introduction  of  platinum  foil  to  facilitate  solution  of 
other  metals  is  no  novelty,  but  I  found  it  convenient  to  use  a  modifi- 
cation, which  I  consider  sufficiently  important  to  note. 

From  the  electrical  condition  of  the  platinum  foil  and  its  great 
attraction  for  the  electro-positive  hydrogenium,  an  intermittent  and 
rather  curious  reaction  is  set  up  in  the  flask  where  solution  is  effected. 
The  platinum  foil  sinks  on  its  introduction  until  it  touches  the  particles 
of  metal  Ipng  upon  the  bottom  of  the  flask,  when  it  instantly  becomos 
covered  with  the  electro  positive  hydrogenium,  and  the  foil  rises  to  the 
surface  of  the  liquid,  and  there  discharges  the  hydrogen  gas,  and  then 
■inks  again  until  it  comes  in  contact  with  the  alloy,  when  the  pheno- 
menon is  repeated,  as  long  as  any  alloy  remains.  It  is  therefore  self- 
evident  that  this  intermittent  process  must  greatly  retard  the  consumma- 
tion of  perfect  solution. 

To  remedy  this,  I  substitute  small  spheres  of  platinum  about  the 
size  of  swan  shot.  The  rounded  particles  of  platinum  act  perfectly,  the 
hydrogen  being  much  more  readily  illiminated  from  Uie  spherical 
surface,  and. in  no  case  does  the  platinum  float.  If  the  operation  is 
performed  in  a  flask  as  recommended,  from  the  shape  of  the  vessel  these 
particles  of  platinum  are  also  in  actual  contact  with  the  alloy  during 
the  whole  of  the  process. 

Solution  is  effected  in  nearly  half  the  time,  and  the  loss  upon  the 

*  Continued  from  Ser.  II.  Vol.  I.  Science,  p.  105. 

B.  I-  A.  FKOC,  SEU.  U.  VOL.  11.,  BCaLKNCE.  M 


y 


82  Proceedings  of  the  Royal  Irish  Academy, 

platinum  shot  (probably  from  attrition)  was  found  to  be  only  0*0001 
per  cent,  during  the  solution  of  four  grammes  of  alloy.  I  may  mention 
that  the  platinum  shot  referred  to  can  be  procured  at  any  of  the 
metallurgists  who  produce  the  fused  platinum  in  this  form. 

4. — On  Fhtoreseenee  as  a  Means  of  detecting  Adulteration, 

The  following  note  will  be  interesting  as  illustrating  how  the  fluor- 
escence of  any  substance  may  be  used  for  its  detection  in  the  presence 
of  a  non-fluorescent  substance  : — 

About  seven  years  ago,  I  made  use  of  this  phenomenon  for  the 
detection  of  turmeric  when  present  in  mustard  in  a  report  upon  the 
commercial  aspect  of  that  substance.* 

Lately  it  has  b*?en  referred  to  by  one  of  the  public  analysts  in 
England,  as  a  method  by  which  turmeric  may  be  detected,  and  as  it  is 
so  extremely  delicate  in  its  results,  and  yet  so  easy  of  application,  I 
have  thought  it  desirable  to  draw  attention  to  the  general  principles 
upon  which  this  phenomenon  of  fluorescence  may  be  used  for  such 
purposes,  and  also  with  the  view  of  laying  claim  to  the  idea. 

If  the  adulterant  is  fluorescent,  and  the  substance  into  which  it  is 
introduced  is  non-fluoresoenty  we  have  at  once  a  ready  means  of 
examining  any  number  of  samples  with  much  more  delicacy  than  the 
usual  chemical  reactions  will  give.  Thus,  let  us  take  the  one  to  which 
we  have  already  referred,  the  mustard  of  commerce. 

The  seeds  of  the  black  or  white  mustard  yield  a  yellow,  colouring 
matter  soluble  in  spirit  of  wine  which  is  devoid  of  fluorescence. 
Turmeric  is  always  present  in  the  inferior  qualities  of  this  condiment 
because  the  actual  adulterant  is  wheaten  flour  or  rice,  the  turmeric 
being  necessary  to  bring  the  white  adulterant  up  to  the  same  shade 
as  the  ground  mustard  seeds,  therefore  the  samples  vary  from  0*5 
per  cent,  to  0*05  per  cent,  of  turmeric.  Now,  with  such  minute 
quantities  of  turmeric  the  alkaline  test  is  very  unsatisfactory — in  fact, 
all  chemical  reactions  are  unsatisfactory  when  dealing  with  such  a 
minimum  of  adulteration, 

But  the  great  elegance  of  this  fluorescent  test  consists  in  the  fact 
that  within  reasonable  limits,  the  more' dilute  ths  solution  the  more 
strongly  does  the  fluorescence  test  come  out.  The  non-fluorescence  of 
the  colouring  matter  of  all  substances  that  are  adulterated  with  a 
fluorescent  substance  should,  in  the  flrst  instance,  be  exactly  and 
scientifically  determined.  This  is  easily  done  by  any  one  who  has  the 
Decessarr  arrangements.  In  the  case  of  the  mustard  yellow,  Mr.  H^ 
Draper  kindly  examined  it  for  me,  by  the  light  of  the  spark  formed 
between  two  steel  wires  (such  a  spark  being  the  best  for  the 
purpose), 

*  XeHeal  Frei*  and  a>M^.— Beport  on  the  Adulteration  of  MuBtard.  Yol.  8. 
New  Series. 


TiCHBORNE -riaJora^ory  Notea.  83 

The  steel  points  were  placed  in  connexion  with  a  four-inch  inten- 
sity coil  and  a  small  leyden  jar  was  interposed  in  the  circuit.  The 
battery  used  consisted  of  three  Groves  elements.  In  examining  by  this 
method,  ordinary  glass  yessels  must  be  discarded,  because  even  the 
strongly  marked  fluorescence  of  turmeric  is  more  or  less  masked  by  the 
blue  fluorescence  of  the  glass. 

In  a  quartz  cell  (two  plates  of  quartz  in  a  frame  of  gutta  percha), 
these  observations  can  be  carried  on  with  the  greatest  accuracy.  Mr. 
Draper's  observations  prove  that,  whilst  the  colouring  matter  of  the 
true  seeds  gave  no  fluorescence,  the  presence  of  so  small  a  quantity  of 
turmeric  as  *005  per  cent,  could  be  readily  detected. 

Before  we  are  justified,  however,  in  using  this  phenomenon  as  the 
test  for  the  presence  of  any  substance,  it  is  necessary  to  put  it  to  a 
crucial  examination,  such  as  that  detailed  above  to  find  out  how  far 
the  particular  substance  under  examination  is  capable  of  giving  fluor- 
escenx^e.  But  it-  is  not  at  all  necessary  that  we  should  submit  it  to 
the  light  of  a  spark  in  the  practical  application  of  the  test.  The 
fluorescence  of  an  ordinary  white  glass  flask  is  not  observable  under 
the  ordinary  diffused  light  of  a  laboratory,  but  the  ordinary  fluores- 
cent substances  (so  called),  are  easily  recognized  under  such  condi- 
tions. It  is  only  necessary  therefore  to  form  a  tincture  of  the  sub- 
stance to  be  examined.  The  observation  of  Mr.  Homer*  who  finds 
that  fluorescence  is  wonderfully  developed  by  castor  oil,  may  be 
made  use  of  with  great  advantage.  A  drop  of  castor  oil  that  has  been 
passed  through  adulterated  mustard,  upon  a  filter,  appears  green 
when  dropped  upon  a  black  plate  in  ordinary  daylight.  If 
the  mustard  is  pure,  no  coloration  will  be  perceived.  I  have 
met  with  some  specimens  of  '^  Saffron,*'  (the  stigma  and  style  of 
Croetu  Mtivus),  which  give  a  fluorescence.  They  were  evidently 
adulterated  because  the  flowers  of  safi&on  give  no  fluorescence.  This 
saffron  is  a  most  expensive  drug,  and  is  therefore  very  liable  to 
adulteration. 

6. — On  the  Printing  Inks  of  the  bixUenth  and  Seventeenth  Centuries, 

The  Printing  Inks  of  the  present  century  differ  somewhat  from 
those  of  the  sixteenth  and  seventeenth  centuries,  and  as  this  differ- 
ence may  affect  the  preservation  of  valuable  works  of  art,  I  have 
thought  it  desirable  to  embody  my  observations  upon  this  subject  in  a 
short  note. 

The  present  ink  used  in  printing  books  and  valuable  works  of  art, 
essentially  consists  of  Carbon  in  a  flne  state  of  division,  ground 
up  with  a  mixture  of  oils,  soaps,  and  a  substance  called  printer's 
varnish. 

This  last  named  substance  may  be  viewed  as  the  important  vehicle 
by  which  the  Carbon,  or  pigments,  is  bound  to  the  surface  of  the 

*  Philosophical  Magazine,  September,  1874. 


84 


Proceedings  p/  the  Uoyal  Irish  Academy, 


paper.  The  printer's  vamiBb  is  in  all  good  printing  ink  linseed  oil, 
more  or  less  oxidized — bnt  tbe  oxidation  may  vary  in  degree  from  its 
first  stages,  known  as  ordinary  drying  oil,  and  made  by  the  action  of 
aeetate  of  lead  upon  linseed  oil,  or  it  may  be  burnt  until  it  becomes 
a  stringy  yamish  that  con  be  drawn  into  threads. 

The  first  is  a  fluid  linseed  oil  hardly  changed  in  its  properties, 
whilst  the  last  is  a  tough  reeinous  mass  scarcely  soluble  in  oils,  and 
quite  altered  in  character  from  the  original  compound.  This  last  may 
be  considered  as  a  glyceride  of  lineolic  acid. 

I  have  found  that  the.older  printing  inks  are  more  easily  saponi- 
fied and  washed  off  by  alkalies,  than  tiiose  of  the  last  century,  and 
that  in  this  respect  there  is  a  marked  difference.  In  their  general 
character  they  agree,  as  carbon  seems  to  have  been  the  basis  of 
printing  ink  from  the  time  of  Johann  Faust,  and  from  this  reason 
printed  matter  will  bear  the  action  of  acid  oxidizers,  or  bleachers,  with 
impunity ;  but  many,  if  not  all,  the  printing  inks  of  the  fifteenth 
and  sixteenth  centuries  arp  more  or  less  sensitive  to  the  action  of 
alkalies.  Some  specimens  are  so  extremely  sensitive  to  this  alkaline 
influence  that  on  introducing  them  into  a  weak  solution  of  ammonia, 
the  characters  instantly  float  off  the  surface  of  the  paper,  although 
they  may  have  previously  withstood  the  action  of  a  powerful  acid 
bleaching  bath.  The  only  explanation  that  I  can  offer  is  that  the  oil 
or  oils  used  as  vehicles  were  not  formerly  submitted  to  the  boiling 
process,  which  in  the  more  modem  inks  has  thoroughly  resinified 
them. 

It  is  also  probable  that  copaiba  or  other  balsams  were  freely  used 
in  the  more  ancient  inks.  These  balsams  are  easily  acted  upon  by 
diluted  alkalies. 

It  will  be  seen  by  the  following  details  that  this  peculiarity  was 
not  confined  to  one  country. 


Ink  insoluble^  or  nearly  insoluble  tn 

alkalies. 
Various   pamphlets  published  in 

England  and  Ireland,  1720  to 

1730. 
Modem    English    Inks,  all   the 

specimens  tried. 
Modem  Leipzig  Ink. 


Ink  soluble  in  diluted  ammonia. 

''Agricola.    De     re    metallica," 

BasileoB,  1561. 
Some  of  Albert  Durer's  plates. 
**Libri  Solomonis,"  Paris,  1642. 
*'  Titi  Livii  Historiamm  Libri,*' 

Amsterdam,  1635. 
"Lo     Martyrologe      Romaine," 

Lyons,  1636. 
**  Portraiture     of     his     Sacred 

maiestie,*'  London,  1648. 


a_ 


Archer — Oh  Apothecia  in  Afgce.  85 


XV, — Ok  Apothecia  occurriko  in  some  Scytoxematotjs  aitd  Sirosi- 

PHONACEOUS  AlGJB,    IK  ABDITION   TO   THOSE   PREYIOUSLT   KKOWK.       By 

WnxiAH  Archer,  M.  R.  I.  A.     (With  Plate  6.) 
[Read  December  14,  1874.] 

It  is  now  some  years  since,  npon  examining  some  examples  of  the  hy 
no  means  uncommon  plant,  long  (and  by  some  still)  accepted  as  algal, 
Stiff onema  atrovirensy  Ag,,  that  I  was  attracted  by  the  peculiar  en- 
largements of  the  branches,  and  was  much  interested  in  perceiving  that 
this  plant  showed,  imbedded  in  these  swellings,  distinctly  lichenous 
fructification — apothecia,  as  well  as  the  so-called  spermogonia.  Upon 
searching  out  the  literature  of  the  subject,  I  found  from  Bomct's  valu- 
able paper*  that  my  discovery  had  been  previously  well  known,  and 
that  my  specimens  fully  bore  out  the  description  he  gave,  with  the 
exception  of  the  hyphae  subsequently  discovered  by  Schwendener. 
Bomet,  indeed,  argued  from  the  fructification  which  he  had  proved  to 
belong  to  this  form,  that  it  should  no  longer  be  accounted  an  alga,  but 
relegated  to  the  lichens  as  Ephehe  pubescens.    ' 

But  it  occurred  to  me  that  Bomet* s  supposition,  at  the  period  of 
his  writing  the  memoir  on  Ephebe,  that  other  forms  of  apparent  affi- 
nity {Stiffonema  mamillosum,  St.  mammiferum  and  others)  were  of 
another  and  different  nature — that  is,  **  algSB,"  whilst  E.  puheseens 
was  a  **  lichen," — could  not  be  borne  out.f  It  struck  me,  indeed,  that 
if  Stiffonema  atrovirens  were  no  alga,  but  a  veritable  lichen,  that  then 
the  other  Sirosiphonacea  and  Sci/tonemaceaj  if  likewise  .patiently  ex- 
amined, must  prove  themselves  of  the  same  nature.  Stiffonema  mamil- 
losum  and  Sirosiphon-  and  Scytonema-forms,  I  thought,  could  hardly 
be  less  lichens  than  Ephebe  pubescent  itself ;  nor  was  I  then  aware  that 
such  in  some  cases  had,  since  Bomet's  paper  referred  to,  been  actually 
accepted  as  a  fact. 

Having  at  that  time  more  frequent  opportunity  of  finding,  amongst 
the  Wicklow  hills,  the  commoner  representatives  of  the  class  than  more 
recently,  I  then  made  a  considerable  number  of  gatherings  and  ex- 
amined them  as  closely  as  I  could  for  "  apothecia."  I  found  it  a  more 
tedious  labour  than  might  be  supposed,  for,  though  I  by  and  by  found 
apothecia  in  three  genera,  I  had  to  make  very  many  hundred  gather- 
ings and  examinations  in  order  to  be  successful  in  encountering  even 
a  few  "fertile"  specimens;  for,  though  possibly  more  frequently 
"  fruiting "  than  one  might  suppose  from  that  fact,  the  opacity  and 

*  Bomet,  '*  Beoherches  sur  la  Structnre  de  V Ephebe  pubeecena"  in  '*  Ann.  dcs 
Soi.  Ntturelles,'*  8  ser.,  torn,  xviii.,  p.  166. 
t  Bornet,  loc.  cit.,  p.  167. 

.     X.  X.  A.  PBOG.,  Sm.  IX.  VOL.  H.,  SCXEKCB.  N 


^6  Proceedings  of  the  Royal  Irish  Academy, 

'closely  tufted  habit  of  most  of  these  forms  contribute  to  rendering  the 
little  dark  lateral  tubercles  usually  formed  by  the  apothecia  somewhat 
Teadily  overlooked,  whilst  they  might  in  some  forms  be  eyen  passed 
•over  under  a  low  power  (the  only  useful  way  of  searching)  as  merely 
rudimentary  '*  branches." 

It  is  matter  of  regret  to  me  now  that  I  did  not  at  the  time  bring 
forward  some  notes  upon  these  forms  before  the  preparations  I  had 
made  had  become  spoiled ;  and  it  is  also  a  matter  of  still  greater  regret 
that  I  did  not  secure  some  drawings  more  in  detail  than  the  rough 
sketches  I  am  able  to  ofPer.  But  as  even  a  chalk  drawing  on  a  black 
board  is  better  than  none,  so  the  accompanying  figures  (PL  6)  may  serve 
a  temporary^  purpose  until  better  are  forthcoming  from  some  source, 
whilst  the  figures  of  the  spores  themselves  may  be  accepted  as  accurate. 

I  at  once  assumed  from  our  knowledge  of  £phebe  pubescem^  coupled 
with  the  additional  fact  of  having  found  apothecia  in  Scytonemaf  Sirosi- 
phoitf  Stigonema  {mamillosum),  that  these  genera  and  probably  the 
whole  of  the  Scytonemacea  and  SirosiphonacetBy  could  be  no  longer 
properly  accoimted  algsB,  but  should  be  relegated  with  Ephehe  to  fiie 
lichens. 

But  another  and  a  different  solution  is  put  forward  now-a-days  by 
Professors  de  Bary  and  Schwendener,  and  those  (Reess,  Bomet,  TVeub, 
and  others)  who  accept  the  new  doctrine  of  the  nature  of  lichens.  It 
has,  as  is  well  known,  been  previously  long  supposed  that,  assuming 
the  gonidia  to  be  really  organs  of  the  lichens,  these  may  here  and  there 
(and  by  no  means  urfrequently)  become  detached  from  the  parent  plant, 
and,  under  conditions  unfavourable  to  their  forming  a  new  lichen, 
carry  on  an  independent  (probably  abnormal)  alga-like  existence ;  and 
hence  that  many  of  the  so-called  unicellular  and  some  of  the  filamen- 
tous algal  growths,  which  may  have  been  regarded  as  specifically  dis- 
tinct organisms,  should  really  be  expunged  the  list  of  independent 
plants.  On  the  other  hand,  Schwendener  and  the  new  school  hold  that 
the  **  lichen-gonidia  "  are  veritable  unicellular,  or,  as  the  case  may  be, 
according  to  the  type  of  lichen,  filamentous  algae  which  vegetate  within 
the  lichen-thallus  as  the  serviceable  (assimilating)  host  plants  of  a 
parasitic  ascomycetous  fungus,  the  **  lichen-hypha."  A  resufiiS  of 
the  whole  question,  of  the  views  put  forward  and  the  arguments 
adduced,  so  far  as  the  discussion  has  reached,  both  for  and  against, 
I  have  recently  endeavoured  to  bring  together,*  and  it  is  hence  super- 
fluous to  attempt  here  to  recapitulate  the  particulars  and  points  of  his 
hypothesis,  except  as  they  bear  upon  the  group  immediately  in  question. 

In  his  able  and  interesting  work  on  the  ^*  Gonidia-forming  Algal- 
type8»"t  a^d  beginning  with  the  "  Phycochromaceous  "  series  {Nbato- 
china,  Nag.),  Schwendener  places  the  Sirosiphonacea  ijx  the  front  rank. 


*  "  Quart.  Journal  Mic.  Science,"  vol.  xiii.,  N.  S.,  p.  217 ;  also  vol.  xiv.,  p.  116, 
in  which  places  the  references  to  the  various  authors  are  given. 

t  Schwendener :  "  Die  Algentypen  der  Flechtengoni£en,"  Basel,  1860. 


ArcheH — On  Apothecia  in  Algof,  87 

He  justly  obsenrea  they  should  begin  the  series,  amongst  the  bluinh- 
green  filamentous  forms,  by  reason  of  the  well-expressed  contradistinc- 
tion offered  by  them  between  apex  and  base,  also  by  reason  of  their 
being  marked  by  a  formation  of  true  branches,  as  weU  as,  in  their 
higher  representatiTes,  showing  an  e\'ident  accession  to  their  thickness 
by  subsequent  growth.  Possessing  these  specialities,  they  at  the  same 
time,  however,  show  an  unmistakable  affinity  on  the  one  hand  to  the 
8eyt4memea  and  JRivulariea  in  the  common  possession  of  **  heterocysts  " 
and  an  apical  growth,  and  on  the  other  to  the  Nostochacea^  which, 
wanting  apical  growth,  form  a  transition  to  the  Oseillariea. 

Prior  to  the  propounding  of  the  new  hypothesis,  however,  certain 
of  these  forms,  which,  if  met  with  without  apothecia,  would  have  been 
referred  to  the  genus  SeyUmema,  had  been  found  with  apothecia  and 
thereupon  new  genera  were  formed  for  them  by  Itzigsohn  and  Nylander 
under  the  names  EphebeUa,  Itzigsohn,  and  Gonumema,  Nyl.  (or  Ther- 
fmUi$y  Fr.  ?).  In  fact,  they  seem  to  have  regarded  the  *'  barren  "  and 
the  '^  fertile  "  plant  as  each  belonging  to  distinct  genera,  even  as  ap- 
pertaining to  different  classes — ^that  is,  that  the  '*  barren  "  was  to  be 
accounted  an  "  alga  "  and  the  **  fertile  "  a  **  lichen." 

Of  course,  had  Schwendener's  view,  but  comparatively  lately  put 
f orwardy  been  then  current,  and  had  it  been  adopted  by  the  discoverers 
of  those  apothecia-bearing  8iro9iphonaeem  and  Seytonemacea^  the  case 
would  have  been  different:  the  new  name  would  in  that  case  have 
been,  as  I  take  it,  understood  to  be  applied  to  the  ^^ncw  ascomyce- 
tous  parasite,"  within  the  Sirostphonj  or  the  Seytonema — the  double 
names  should  still  pass  current,  for,  in  that  case,  they  would  stand  for 
essentially  distinct  things,  and  no  less  so  because  these  occur  sometimes 
living  in  consort  and  in  a  state  of  mutual  physiological  dependence. 

The  present  communication,  therefore,  loses  much  of  the  signifi- 
cance it  might  have  been  at  least  temporarily  held  to  possess,  from  not 
being  brought  out  at  the  time  the  observations  were  made,  but  after 
the  new  theory  had  been  not  only  propounded,  but  had  gained  a  large 
amount  of  currency. 

Nevertheless,  although  more  superficially  put  forward  than  if  I  had 
made  the  matter  public  at  the  time  of  the  observations,  and  when  these 
were  fresh  in  my  mind,  this  will,  I  think,  be  the  first  record  of  ''  apo- 
thecia "  being  noticed  in  at  least  five  fresh  forms  or  species  referrible  to 
separate  "genera"  {8cyt(mema,  Sirosiphony  Stigonetna)  in  the  algal  point 
of  view.  If  this  record  had  been  brought  out  at  that  time,  indeed,  it 
would  have  pointed,  as  I  should  have  taken  it,  to  the  assumption  that 
these,  in  place  of  genera  of  algae,  were  in  truth  genera  of  lichens — ^not 
'*  new  "  lichens,  but  lichens  not  taken  previously  "  in  fruit." 

With  respect  to  I^hehe  and  Spilanema,  Schwendener  argues,  that 
a  genetic  conne^on  between  the  hyphae  and  the  gonidia  is  impossible. 
For  the  whole  chain  of  gonidia  leads  onwards  to  the  apical  cell,  by  the 
unlimited  subdivision  of  which  new  cells  continuously  originate,  which 
are  themselves  again  to  be  regarded  as  mother-cells  (in  those  genera)  uf 
so  many  groups  of  gonidia.  The  assumption  of  a  new  formation  of 
gonidia  by  growing-off  from  the  hypha  has  no  justification  whatever; 


88  Proceedings  of  the  Rayal  Irish  Academy, 

those  who  hold  such  a  view  must  take  refuge  in  the  aBsnmption  of  the 
formation  of  the  £rst  gonidium  in  the  germination  of  the  spore — ^a 
process  which  has  not  yet  been  observed  in  any  lichen,  and,  d  priori, 
never  will  be. 

But  it  must  be  pointed  out  that,  according  td  Schwendener  and 
others,  Scytonematous  and  Sirosiphonaceous  algse  are  claimed  as  form- 
ing ^'gonidia"  under  two  distinct  circumstances  or  conditions:  they 
are,  according  to  their  researches,  to  be  found  in  certain  lichens,  either 
as  mere  accidentally  detached  portions  of  filaments  wholly  suiTounded 
and  involved  by  the  hyphae,  and  caught  up  bodily  in  the  substance  of 
the  lichen-thallus  in  a  completely  disorderly  manner,  or  they  exist  as 
perfect  plants  of  their  type  as  alg8&,  the  alga-thallus  quite  unaltered  in 
outward  configuration,  but  permeated  along  the  length  of  the  filaments 
by  the  hyphae,  which  run  between  the  rows  of  green  cells.  When  the 
algae,  as  is  assumed,  are  in  the  former  way  compelled  to  become  the 
*'  gonidia-formers,"  it  is  the  hyphae  (not  the  algae)  which  must  be  held 
to  control  the  configuration  of  the  thallus  and  determine  the  character- 
istic build-up  of  the  "  lichen ; "  when  the  algae  serve  in  the  latter  way 
as  gonidia  to  the  intruding  hyphae,  the  former  (not  the  hyphae)  retain 
their  proper  "  specific  "  exterior,  the  build-up  of  the  (algal)  thallus  is 
not  externally  altered,  and  it  is  only  a  microscopical  examination  which 
would  reveal  anything  unusual  or  offer  any  'Michonous"  indication. 
It  is  as  regards  this  latter  gonidial  condition  that  Schwendener's  argu- 
ments, as  to  the  impossibility  of  the  genetic  relationship  of  the  hyphse 
and  the  young  apical  gonidia,  bv  reason  of  the  latter  being  formed 
prior  to  the  arrival  at  the  apex  of  the  hyphal  filaments,  are  directed, 
and  to  this  condition  it  is  that  the  notos  here  brought  forward  apply. 

One  of  the  most  common  of  the  Scytonemacea  is  the  Scytonema  myo- 
ckrous,  forming  silky  cushion-like  tufts  on  wet  rocks,  when  dry,  of 
mouse  colour,  when  wet,  more  of  an  olive  hue ;  it  seems  to  love  best  a 
pretty  constant  trickle,  and  if  the  force  of  the  little  current  be  some- 
what strong,  the  mass  may  form  a  rather  long  drawn-out  pad,  stretch- 
ing down  the  inclination  of  the  surface  over  which  the  little  flow  de- 
scends. Very  often  in  my  searchings  I  gathered  little  portions  from 
various  sites,  sometimes  very  wet,  sometimes,  indeed,  dried  up  by 
drought,  and  once  only  was  I  so  fortunate  as  to  find  examples  showing 
apothecia.  I  regret  I  have  mislaid  my  rough  drawing  of  the  apothe- 
cium  itself,  but  fig.  1  is  a  sketch  of  the  spores  within  an  ascus.  The 
general  appearance  of  the  apothecium,  however,  is  like  that  of  Sirosi- 
flhon.  The  asci  were  accompanied  by  linear  paraphyses ;  the  spores  were 
four  in  an  ascus,  nearly  colourless,  broadly  elliptic,  simple,  with  two 
bright  corpuscles,  each  with  a  minute  dot  in  its  centre  immersed 
therein,  one  towards  either  end.  Length  of  the  spore,  j^",  breadth, 
.4"  (figs.  1,  2). 

Another  Seytonemay  whose  precise  identity  seems  difficult  to  deter- 
mine, also  presented  apothecia.  This  too  I  found  on  only  one  occa- 
sion ;  the  contents  usually  formed  a  thin,  somewhat  irregular,  central 
string  up  the  middle  of  a  somewhat  thick  striated  sheath,  except  near 


Archer — On  Apothecia  in  AlgcB.  89 

the  apices  of  the  *'  branches  "  (which  Bometimes  were  given  off  singly) 
in  which  they  were  thicker  and  quadratic  (tigs.  3-6).  In  this  Seyto^ 
nema  the  nearly  mature  apothecia  were  globose,  smooth,  shining,  of  a 
dark  brownish-chocolate  colour,  usually  placed  somewhere  along  the 
length  of  the  filament,  but  might  be  occasionally  terminal  (figs.  3-6). 
Sometimes  they  seemed  almost  to  form  an  interruption  of  the  continu- 
ity of  the  filament,  or  as  if  inserted  into  a  special  rounded  excavation 
in  it,  and  separated  from  it  by  a  sharp  line  of  demarcation  (fig.  4). 
Certain  of  the  filaments  showed  here  and  there  what  seemed  to  be 
agglomerations  of  brownish-coloured  granules,  which  by  their  quantity 
caused  a  distension  of  the  filament  and  an  interruption  of  the  string  of 
contents ;  these  I  took  to  be  incipient  apothecia,  judging  from  their 
position;  but  this  is  of  course  not  certain  (figs.  9-11).  The  more 
mature  apothecia  seemed  somewhat  depressed  at  the  top  where  the 
opening  occurs  (fig.  6).  Like  the  apothecia  of  all  these  forms  the 
present  were  very  tough  and  intractable,  the  only  plan  to  obtain  the 
asci  separate  with  their  spores,  on  account  of  their  minuteness,  being  to 
(^use  them  to  become  ejected  by  (very  forcible)  pressure.  In  the 
present  instance  this  was  of  more  than  usual  difficulty,  and  I  was  un- 
able to  press  out  an  ascus  intact  to  discover  if  it  was  4-  or  8-spored ; 
I  believe,  however,  the  latter.  The  paraphyses  were  slender,  linear. 
The  separated  spores  themselves  were  somewhat  readily  obtained,  and 
they  are  different  from  the  preceding,  being  much  longer  and  nar- 
rower, of  lanceolate  outline,  simple,  colourless,  with  a  minute  dot- 
like   corpuscle  towards   either    end;  length  of  spore,  j^^/',   breadth, 

Coming  to  Stronphonacea,  another  case  is  offered  by  8.  alpinus. 
Here  the  apothecia  were  smooth  but  not  shiny,  blackish,  globular, 
variously  situated,  sometimes  in  the  axil  of  a  branch  (fig.  13),  some- 
times along  the  length  of  the  filament  (fig.  12),  or  even  terminal. 
Here,  as  elsewhere,  it  was  only  by  pressure  that  the  asci  and  spores 
could  be  ejected.  The  asci,  as  elsewhere,  at  first  filled  with  a  grumous 
granular  substance  (figs.  16,  17),  were,  when  mature,  S-spored 
(fig.  18).  Sometimes  I  saw  asci  with  the  contents  contracted  to  a 
broadly  fusiform  figure,  and  then  divided  transversely,  thus  pro- 
ducing two  conical  bodies  as  if  base  to  base  (fig.  16).  The  para- 
physes seemed  to  be  of  two  lengths,  the  shorter  about  half  the  length 
of  the  asci,  linear,  pointed,  the  longer  about  one-half  longer  than  the 
asci,  nearly  twice  broader  than  the  former,  with  truncate  end  (fig.  17). 
The  spores  here  were  different  from  either  of  the  preceding,  being  uni- 
septate,  oblong,  somewhat  constricted  at  the  middle  opposite  the  sep- 
tum, each  end  broadly  rounded,  colourless,  each  cavity  lowing  a  single 
central  bright  minute  corpuscle ;  length,  j^'^,  breadth,  ^-/^  (fig.  14). 

Another  Sirosiphonaceous  form,  8.  pukinatus  or  8,  Heufleri,  showed 
apothecia.  They  appeared  in  a  young  condition  to  be  hemispherical, 
when  mature,  globose,  sometimes  as  if  somewhat  produced  upwards, 
and  truncate  at  the  opening  (fig.  20).  Unlike  the  previous,  they  did 
not  appear  smooth  when  young,  but  as  if  slightly  hirsute  externally 


90  Proceedings  of  the  Royal  Irish  Academy. 

(fig.  19).  The  clavate  asci  sometiines  appeared  somewhat  truncate 
(fig.  21);  poraphyses  very  inconspicuous — ^indeed  I  am  more  inclined 
to  think  there  were  none ;  the  asci  were  densely  crowded.  Many  ex- 
amples showed  asci  filled  with  granular  contents,  the  spores  not  yet 
formed.  The  asci  when  mature  were  8-8pored  (fig.  22),  the  spores 
resembling  in  size  and  figure  (but  were  very  slightly  longer  than)  those 
of  the  second  form  of  ScyUmema  referred  to,  but  they  differed  in  not  hay- 
ing the  two  bright  corpuscles  immersed  therein,  and  in  showing  a  pale 
green  colour.  Thev  were  long  and  narrow-lanceolate,  greenish ;  length, 
,^^  breadth,  O.''  (fig.  23). 

The  last  form  which  rewarded  my  search  in  showing  apothecia  was 
the  form  recorded  in  '^  Flora  Hibemica  "  as  StigtmemamamillosuMf  but 
the  distinction  which  may  exist  between  the  plant  in  question  and 
Stigtmema  mammiferum,  Thwaitcs,  or  Sirosiphon  eoralloides,  Kiitz.,  are 
not  very  apparent.  Our  plant  grows  in  running  water,  attached  to 
stones  at  the  bottom  of  mountain  streams.  It  is  much  more  rare, 
seemingly,  than  any  of  the  previous  species,  and  is  a  very  pretty  plant 
under  a  moderate  power  of  the  microscope,  especially  a  young  and 
flourishing  one,  studded  by  the  curious  short  and  blunt  branches, 
giving  the  "  mamillate  "  appearance,  with  the  phycochromaceous  con- 
tents bright  in  colour.  The  apothecia  resembled  those  in  the  8iro- 
siphon  above  alluded  to ;  they  were  blackish,  globose  {^^,  24) ;  para- 
physes  linear,  somewhat  longer  than  the  asci  (fig.  26) ;  spores  four  in 
an  ascus,  greenish,  uniseptate,  oblong,  the  septum  appearing  like  a 
pale  and  hyaline  slender  transverse  band,  and  somewhat  constricted 
at  the  middle  opposite  the  septum  :  thus  the  halves  ovate,  somewhat 
tapering  to  the  bluntly-rounded  ends,  each  cavity  showing  a  bright 
corpuscle  immersed  in  it ;  length,  ^",  breadth  j~"  (fig.  26). 

In  all  these  forms  I  searched  as  well  as  I  could  for  so-called  sper- 
mogonia,  but  was  unable  to  detect  any.  These  are  comparatively  so 
readily  perceived  in  JSphehe  (I  myself  found  them  before  I  was  aware 
of  Bomet's  published  account  of  them,  or  of  the  apothecia  in  that  plant) 
that  my  non-success  was  the  more  disappointing. 

Nor,  after  many  trials  by  boiling  in  caustic  potash,  was  I  able  to 
satisfy  myself  of  the  presence  of  hyphae,  as  can  be  so  readily  done  in 
JSphehSf  as  first  pointed  out  by  Schwendener ;  there  can,  however,  be 
little  reasonable  doubt  but  that  they  must  exist,  though  the  seeming 
nascent  apothecia  in  the  second  form  of  Scytonema  referred  to  gave  no 
indication  of  their  presence ;  but  that  in  itself  would  prove  nothing,  as 
the  hypha  cannot  be  seen  in  Ephehe  without  boiling  in  potash.  Most 
probably  my  experiments  were  not  conducted  sufficiently  long  or  care- 
fully, for  Bomet  has  shown  the  existence  of  the  hyphse  in  his  Spilo- 
nema  paradoxum,*  and  in  his  Lichenospharia  Lmormandi.^ 

♦  Dr.  E.  Bomet :  "  Description  de  Trois  Lichens  Nouveaux,"  in  "  Memoires  de 
la  Soc.  Imp.  de  Cherbourg,"  vol.  iv.,  p.  226,  t.  i.,  ii. 

t  Dr.  E.  Bomet :  "  Recherchos  but  les  Oonidies  de«  Lichens,**  in  "  Ann.  des 
Sei.  Naturclles,"  5  s^r.,  tome  xvii.,  (of  reprint,  p.  67). 


Archek — Oh  Apothecia  in  Algm.  91 

But  does  it  not  appear  somewhat  inconsiisteiitwlien  Bornet,  in  describ- 
ing his  Liehenotpharia  Zenormandit  makes  use  of  the  following  language 
in  the  generic  character: — ''Thallus  tenellus,  ramosns,  fruticulosus, 
fere  omnino  Btigonematoxdeun,  basi  corticatus ;  "  and  as  descriptive  of 
the  specific  characters — '^Thallus  fusco-niger,  tomentoso-intricatus 
(altitude  vix  2  millim.),  ramulis  divaricatis  subsecundis "  ?  For,  in 
fact,  these  words  simply  describe  the  thallus  of  Siro»%phon  divarieatus, 
Xiitz.,  which  alga  forms  the  host-plant  for  the  peculiar  liehenal  para- 
site in  question.  But  when  he  goes  on  to  describe  the  apothecia,  the 
thecsBy  the  spcrmogonia,  the  spores,  he  is  giving  the  characters  of  the 
latter,  which  is  the  real  ''  new  species."  In  accordance  with  the  new 
theory,  besides  the  hyphce,  this  has  no  thallus  of  its  own ;  the  hyph» 
merely  push  into  the  thallus  of  the  Sironphon,  scarcely  distorting  it  or 
causing  any  outward  alteration,  beyond  the  occasionally  exserted  apo- 
thecia. If  it  were  possible — ^and  there  is  seemingly  no  great  reason  to 
the  contrary — that  the  spores  of  this  self-same  Ztchenospharia  Lenar- 
mandi  should  afterwards  grow  upon  and  into  another  species  of  Siroai- 
phon,  or,  sav  even  into  a  SeyUmema,  then  sotm  of  the  ''  specific  charac- 
ters" as  given,  nay,  even  probably  some  of  the  **  generic,"  would 
disappear  and  others  take  their  place.  It  is  to  be  granted,  indeed,  that 
on  the  new  theory,  when  a  Nostoe  becomes  invaded  by  the  parasite 
which  converts  it  into  a  CdUma,  a  very  considerable  alteration  is  pro- 
duced on  even  the  outward  aspect  of  the  Nbstoc ;  instead  of  a  rounded, 
lobed,  '^  blobby,"  and  soft  lump,  it  becomes  more  or  less  foliaceous, 
less  watery,  and  more  subdivided  ;  but  it  is  the  alga  all  the  time  which 
submits  to  this  alteration :  the  true  Uehen  is  intide^  only  evincing  itself 
externally  by  its  apothecia  and  by  its  action  on  the  alga  (like  a  gaU 
causing  even  greater  modifications  on  a  higher  plant),  inciting  those 
changes  of  external  aspect,  whilst  it  is  at  the  same  time  making  use  of 
the  assimilating  power  of  the  alga  to  do  for  it  what  it  cannot  do  by 
itseH. 

There  can  be  little  doubt  but  that  amongst  these  Scytonematous  and 
Sirosiphonaceous  algse  quite  distinct  forms  occur ;  but,  on  the  other 
hand,  there  can  be  almost  as  little  doubt  but  that  Kutzing  has  vastly 
over-enumerated  them — ^that  many  of  his  so-called  species  are  not  dis- 
tinguishable. Now,  it  is  hard  to  conceive  that  one  and  the  same  para- 
site would  care  very  much  which  of  forms  so  closely  resembling  it  in- 
vaded in  order  to  pursue  its  course  of  life.  Siroaiphon  divarieatua 
seems  not  to  difEer  much  from  8,  alpinua ;  it  is  more  fruticulose,  the 
cells  in  the  central  stems  seem  to  occur  in  more  than  double  series  : 
what  very  perceptible  barrier  is  there  to  the  supposition  that  the  para- 
site, which  invades  the  former  to  form  Lichmoaph^sria  Lenamumdi, 
Bomet,  might  not  at  another  time  invade  the  latter  ?  Would  it  not 
then  fructify  in  the  same  way,  show  spores  alike,  &c.  ?  But  the  para- 
site which  does  really  invade  the  latter  is  not  the  samef  as  the  figure 
herewith  will  show,  not  to  speak  of  the  paraphyses,  so  prominent 
a  ^ture  in  the  latter,  being  absent  in  Bomet's  plant.  Are  these  Scy- 
tonemicolous  and  Sirosiphonicolous  parasites,  then,  so  extremely  parti- 
cular in  their  choice  ? 


92  Proceedings  of  the  Boyal  Irush  Academy. 

See  again  the  two  Scytonemata,  resembling  in  themselves  so  much 
and  yet  with  **  parasites  "  so  distinct ;  the  spores  could  not  be  con- 
founded for  a  moment  (see  figs.  1,  2,  and  fig.  8).  Again,  see  the 
great  resemblance  (but  certainly  not  identity)  between  the  spores  in 
the  second  Scyt^mema  and  in  Sirosiphon  puhinatus,  algae  mutually 
sufficiently  unlike  (see  Figs  8  and  23). 

It  might  again  be  asked  whilst  the  new  theory  is,  as  it  were,  on 
its  trial,  at  what  period  of  the  life  of  the  Scytonema  or  Sirosiphon  does 
it  become  invaded  by  the  parasite  ?  At  what  part  of  the  thallus  does 
it  make  its  entry  ?  It  must  be  near  the  base,  or  at  least  not  very  high 
up,  for  the  hypha  is  found  growing  pretty  nearly  pari  passu  with  the 
growth  of  a  branch  of  the  alga,  and  in  the  same  general  direction. 
But  what  is  to  prevent  the  hypha  growing  in  the  opposite  direction  ? 
Might  it  not  sometimes  enter  near  the  apex  and  grow  backwards  ? 
Might  we  not  expect  sometimes  to  find  hyphse  sticking  out  from 
broken-up  or  distorted  examples  of  these  algse,  and  then  revealing 
themselves  (without  thie  whole  mass  beiag  boiled  in  potash)  whilst  on 
their  way  to  invade  other  examples  of  quite  the  same  alga  ?  Or  must 
the  hypha  appertaining  to  a  particular  plant  have  had  its  commence- 
ment from  a  spore  which  found  its  way  to  and  alighted  somewhere  ex- 
ternally upon  the  particular  Scytonema  or  Sirosiphon  ? 

The  account  given  by  Itzigsohn  of  Ephehella  *  is  incomplete ;  he 
met  with  apothecia  in  his  species  of  "  Scytonema,^^  containing  asci,  but 
they  had  not  as  yet  developed  spores.  The  plant  he  had  in  view  may 
certainly  be  said  to  be  quite  distinct  from  Scytonema  myochrous.  It  is 
probable  the  fructification  would  also  have  been  seen,  if  fully  mature, 
to  have  been  also  specifically  different.  So  also  are  my  two  forms,  both 
in  thallus  and  fructification.  These,  proceeding  on  the  new  theory, 
would,  perhaps,  be  relegated  as  **  new  lichens"  to  Ephehella^  Itzigsohn, 
or  to  Qonionemay  Nylander;  but  neither  is  identical  with  Gonionema 
velutinum,  Nyl.  (of  which  I  have  seen  examples  in  the  late  Admiral 
Jones's  Herbarium),  either  as  regards  thallus  or  spores.  The  three 
other  forms  would  probably  be  referred  as  "new  species"  to  the 
**  lichenous  "  genus  Spilonema,  or  that  referred  to  Sirosiphon  puhinatuSf 
wanting  paraphyses,  might  possibly  be  relegated  to  Lichenospharia. 

An  experimental  decision  of  the  "  gonidia-question,"  so  far  as  it 
relates  to  these  Sc3?tonematous  and  Sirosiphonaceous  forms,  is  sur* 
rounded  by  not  a  few  practical  difficulties.  A  sowing  of  spores  ux>on 
the  algse  (ns  Hocss  did  with  Nostoc)  in  a  natural  condition  could  only  be 
carried  out  by  an  observer  residing  in  or  close  to  the  subalpine  situ- 
ations where  these  plants  flourish,  as  they  could  not  be  "cultivated"  else- 
where. In  order  to  obtain  the  spores  he  would  further  have,  very 
probably,  a  troublesome  preliminary  search,  and,  on  the  other  hand, 
there  would  hardly  be  a  certainty  of  the  plants  selected  for  inoculation 
being  themselves  previously  destitute  of  hyphae  or  apothecia.  Of  course 
small  portions  from  various  places  in  a  tiif t  of  any  given  alya  could  be 

♦  Itzigsohn,  in  "Hedwigia,"  1857,  p.  123. 


Archer — On  Apothecia  in  Algm.  93 

previoualy  well  examined,  which,  though  if  indeed  found  to  represent 
the  alga  ''pure  and  simple,"  would  not  render  it  absolutely  conclusive 
that  some  oth&r  portion  of  the  tuft  might  not  already  have  been  invaded 
by  the  "  parasite."  However,  having  selected  some  plants  for  experi- 
ment, they  should  be  well  inoculated  with  spores  and  portions  removed 
from  time  to  time  for  examination  and  experiment.  If  found  satisfactory, 
it  would  be  interesting  to  try  to  "  cross  "  spores  from  the  same  and 
from  different  species  (as,  for  instance,  such  as  fig.  5  and  fig.  26,  or 
fig.  2  and  fig.  19),  in  order  to  see  the  result,  and  whether  the  apparent 
fixity  of  the  forms  and  the  apparently  extreme  exclusiveness  of  the 
"  parasites"  be  true  or  not,  or  ultimately  whether  the  theory  be  true 
itself  or  not.  Whether,  for  the  time  being,  the  truth  of  the  new  theory 
be  previously  assumed,  or  its  untenability  be  presupposed,  would 
matter  very  little,  if  the  suitable  opportunity  and  ready  field  of  opera- 
tiouB  were  at  command  of  the  observer.  It  would  seem  as  if  in  this 
way  only  can  cither  presupposition  be  justified  or  negatived. 

Pending  the  ultimate  decision  at  which  the  great  lichenists  who 
are  at  work  on  the  broad  question  may  arrive  as  to  the  true  nature  of 
these  interesting  plants,  and  pending,  too,  the  discovery  of  Uie  sper- 
mogonia  of  the  forms  here  referred  to,  as  assisting  to  throw  a  light 
on  their  mutual  affinities  and  relative  position,  I  may  well  leave  to 
more  skilled  hands  the  desultory  notes  brought  forward  in  this  com- 
munication, touching  their  general  bearing  and  ultimate  application 
as  regards  one  of  the  most  interesting  and  problematic  botanical  ques- 
tions of  the  day. 


R.  I.  A.  PROC,  RBR.  11.,  VOL.  H.,  SCIBWCB. 


94  Proceedings  vf  the  Royal  Irish  Amdemi/, 


XVI. — Microscopical  Sthucture  of  Eocks.  Refost  No.  I. — Inoekite 
Rocks.  By  G.  H.  Kinahan,  M.  R.  I.  A.,  &c.  (With  Plates  7 
and  8). 

[Read  June  8,  1874.] 

Iv  these  reports  on  the  microscopical  structure  of  the  Ingenite  Rocks 
it  is  proposed  to  descrihe  each  rock  under  the  names  adopted  hy  me  in 
"  A  Handy  book  of  Rock  Names,"*  while  all  the  minerals  will  be  called 
by  Dana's  names.  With  each  specimen,  prior  to  entering  into  its  micro- 
scopic structure,  will  be  given  a  description  of  the  rock,  as  it  appears 
when  examined  in  the  field,  with  the  naked  eye  or  with  a  pocket  lens. 
In  this  report  the  felspars  will  be  principally  treated  of — the  power 
used,  except  when  specially  mentioned,  being  42. 

In  a  paper  read  November  13th,  1871,  before  the  Academy,  "  On 
the  Granitic  and  other  Ingenite  Rocks  of  Yar  or  West  Connaught,"t 
I  pointed  out  that  the  granitic  rocks  seem  capable  of  being  divided 
into  Intrusive  granite  (Highly  siliceous  granite).  Granite  for  the  moat 
part  non-intrmive  (Basic  or  oligoclase  granite),  and  Elvanyte  (Quartz- 
porphyry  ; J  the  latter  rocks  being  the  passage-rocks  between  the  typi- 
cal granites  and  the  plntonic  rocks.  It  was  also  shown  that  between 
the  typical  Highly  siliceous  granites  and  the  Basic  granites,  there  are 
granites  partaking  of  the  nature  of  the  former  in  being  intrusive  and 
of  the  latter  in  containing  as  essential  constituents,  such  minerals  as 
oligoclase,  amphibole,  and  the  like.  Moreover,  it  was  shown  that 
typical  Basic  granite  seems  to  be  always  more  or  less  of  metamorphic 
origin,  and  that  it  graduates  into  the  Intrusive  oligoclase  granite, 
wHle  the  typical  Highly  siliceous  granite  is  intruded  in  independent 
masses.  Suggestions  were  also  given  as  to  the  probable  formation  of 
the  granites,  but  to  enter  into  that  subject  now,  would  be  foreign  to  the 
purpose  of  this  report ;  we  will,  therefore,  refer  those  interested,  to 
that  paper  and  to  the  Handy  book  of  Rock  Names,  pp.  37  to  39. 

The  first  rocks  to  which  we  shall  draw  attention,  belong  to  the 
second  group  of  granitic  rocks  or  Granite  for  the  moat  part  non-intruaive 
(Basic  or  oligoclase  granite),  the  specimens  having  been  collected  in 
the  Co.  Galway. 

B.*  Porphyritic  granite  from  Knochanavoddy  (Galway  sheet  93). — 
This  rock,  examined  in  the  field,  seems  to  contain  flesh-coloured, 
greenish,  and  dull  white  felspars,  glassy  quartz,  dark  coloured  amphi- 
bole, black  mica,  and  pyrite.     There  are  also  small  spangles  of  white 

♦  Published  by  Kobert  Hardwicke,  London. 

t   Vide  next  paper  and  also  Handy  book  of  Roek  Names, 

X  A  fourth  group,  Frotogeney  is  also  giyen  proYisionally  in  the  Handy  book. 
Protogene  I  now  belieye  ought  to  be  included  among  the  sub-groups  of  the  Basic 
granite. 


KiNAHAN — On  Microscopical  Sti^ucture  of  RocIch.  95 

mica  and  widely  diBseminated  crystals  of  titanite.  The  dull  white  is 
the  most  abundant  felspar  in  the  rock,  but  the  flesh-coloured  appears  in 
lai^  crystals,  often  twins,  and  gives  the  porphyritic  character  to  the 
rock  mass.  Most  of  the  black  mica,  the  amphibole,  and  the  pyrite, 
occur  associated  together  in  nests,  the  quartz  forming  the  skeleton  of 
the  rock.  Of  this  rock  two  slices  were  cut,  one  containing  one  of  the  large 
flesh-coloured  felspar  crystals,  the  other  being  from  a  portion  of  the 
rock  showing  its  ordinary  character.  In  the  latter  slide  we  find  the 
felspars  are  principally  represented  by  the  white  variety,  only  one  or 
two  small  pieces  of  the  flesh-coloured  being  present,  while  the  green  is 
scarcely  represented,  but  in  the  other  slide  edl  the  minerals  mentioned 
in  the  field  list  are  represented. 

No  perfect  crystals  of  any  of  the  felspars  appear  in  the  portions 
of  the  rock  from  which  the  slices  were  cut,,  but  the  flesh-coloured  seems 
to  be  nearest  perfection,  and  we  know  that  in  other  portions  of  the  rock 
mas»,  perfect  crystals  of  this  kind  of  felspar  can  be  procured.  The 
dull  white  and  the  green  felspars  seem  to  be  jumbled  together,  the 
white  predominating.  In  the  nests,  containing  pyrite  amphibole  and 
black  mica,  these  minerals  seem  to  have  crystallized  out  in  the  order  in 
which  they  are  mentioned ;  indeed,  in  places,  the  pyrite  and  amphibole 
seem  to  have  crystallized  out  prior  to  the  felspars,  as  perfect  crystals  of 
both  occur  in  them,  but  the  mica  seems  to  have  been  formed  sub- 
sequently, as  flakes  of  both  black  and  white  mica  are  found  in  places 
margining  the  felspars.  The  ma^  of  the  quartz  flUs  the  vacancies  left 
after  the  other  minerals  were  formed,  but  blebs  of  quartz  occur  in  the 
felspars.     The  titanite  when  it  occurs  is  always  in  well  formed  crystals. 

Flesh-coloured  felspar, — This  according  to  Haughton  is  orthoclase. 
It  seems,  however,  to  be  very  irregularly  constituted  and  to  contain 
many  impurities.  When  we  examine  a  slice  of  white  orthoclase  from 
Ytterby,  Sweden,  for  a  specimen  of  which  I  am  indebted  to  my  col- 
league, F.  Butley,  F.  G.  S.,  we  find  it  to  consist  of  nearly  parallel 
transparent  and  semitransparent  lines  (see  fig.  1,  PI.  7)  alternating,, 
which  under  a  higher  power  (238)  shows  the  lining  to  be  due  to  sys- 
tems and  lines  of  minute  gas  bubbles.  This  structure  is  traversed 
obliquely  by  lines  of  fracture,  (?)  and  when  examined  with  the  polar- 
izer the  matrix  of  the  mineral  appears  mottled  in  places  with  more  or 
less  irregular  specks  and  patches ;  it  is  sometimes  marked  with  irregu- 
lar lines,  and  in  some  places  exhibits  a  tendency  to  a  structure  parallel 
to  the  lines  of  fracture  (?).  Under  the  low  power  (42)  few  included 
minerals  were  observed,  the  most  remarkable  being  small  crystals  of 
pyrite  (?)  and  minute  blebs  of  quartz. 

In  one  of  the  slices  of  the  Enockanavoddy  granite,  there  is  a  large 
twin  crystal  of  flesh-coloured  orthoclase,  in  which  the  junction  of  the 
crystals  is  most  marked.  In  the  left  hand  crystal  at  the  top  there  is  a 
wavy  oblique  lining  that  does  not  appear  in  the  rest  of  the  portion 
under  examination,  but  the  most  conspicuous  structures  in  both  crystals. 
are  irregular  and  irregularly  placed  lines  rudely  parallel  or  nearly  so 
to  the  junction  of  the  twins,  and  this  structure  under  a  power  of  296 


96  Proceedings  of  the  Royal  Iriah  Academy. 

is  found  to  be  due  to  systems  of  minute  gas  bubbles,  while  the  oblique 
lining  seems  to  be  due  to  lines  of  shading  caused  by  transparent  and 
translucent  layers. 

In  this  mineral  there  are  numerous  inlying  minerals  or  mineral 
Becretions,  the  most  conspicuous  being  blebs  of  quartz  which  usually 
have  translucent  nuclei,  but  a  few  have  similar  characters  to  the  blebs 
of  quartz  characteristic  of  the  Elvanytes— other  minerals  observed  were 
amphibole,  mica,  pyrite,  and  magnetite.  In  fig.  3,  PI.  7,  is  shown  a 
bunch  of  three  crystals  of  amphibole  associated  with  a  flake  of  mica. 
In  the  associated  orthoclase  was  observed  a  faint  lining  parallel  to  the 
longer  axis  of  the  amphibole  crystals,  but  the  most  conspicuous  struc- 
ture is  that  of  the  lines  due  to  the  systems  of  minute  bubbles,  some- 
what similar  to  those  mentioned  when  describing  fig.  2,  PL  7.  In  the 
neighbourhood  of  the  amphibole  crystals,  are  many  foreign  particles 
scattered  about,  some  being  roundish,  but  a  few  having  irregular  crys- 
talline forms,  ^1  have  translucent  centres  but  some  are  surrounded  by 
cTTstalline  rims  of  quartz.  A  remarkable  crystalline  mass  observed  in 
the  orthoclase  is  represented  in  fig.  4,  Plate  7.  The  dull  grey  por- 
tions are  slightly  iridescent  and  of  similar  appearance  to  the  dull  white 
fjlspar  hereafter  to  be .  described.  In  the  orthoclase  are  also  Bubvi- 
treous,  opaque  black  crystals ;  two  of  which  are  represented  in  fig. 
2,  PL  7. 

Under  a  power  of  238  some  of  the  minute  opaque  specks  appear  to 
be  magnetite  while  others  are  probably  pyrite  (fig.  5,  PL  7). 

In  the  smaller  crystals  and  masses  of  the  flesh-coloured  orthoclase, 
the  structure  appears  to  be  more  regular;  as  we  find  the  crystals 
crossed  by  wavy  lines  (fig.  6,  PL  7)  which  under  a  higher  power  (238) 
arc  found  to  be  due  to  clouds  of  minute  gas  bubbles  which  lie  in  irre- 
gtilar,  more  or  less  parallel  planes.  These  smaller  crystals  of  the 
orthoclase  seem  to  contain  only  a  few  imbedded  minerals  principally 
blebs  of  quartz  and  pyrite  (?). 

Dull  white  felspar  ( Adularia?). — ^This  mineral  in  the  Enockanavoddy 
grnnite  seems  generally  to  occur  massive ;  there  are,  however,  in  places 
well  developed  crystals,  sometimes  of  considerable  size.  Under  the  low 
power  (42)  this  mineral  seems  to  be  irregular  in  its  structure.  Some 
miisses  are  nearly  opaque,  but  in  them,  irregularly  scattered,  are 
numerous  iridescent  specks,  while  in  some  are  tranQlucent  portions, 
seemingly  of  a  triclinic  felspar,  as  they  transmit  ribands  of  light  (fig. 
7,  PL  7).  In  a  crystalline  mass  (fig.  8,  PL  7)  was  detected  a  Imed 
structure ;  under  polarized  light,  opaque  lines,  more  or  less  regular, 
alternating  with  subtranslucent  iridescent  broken  lines.  With  a  high 
power  (386)  the  cause  of  the  lining  is  very  obscure,  as  the  constituents 
are  not  found  to  be  in  layers.  An  opaque  constituent,  however,  has  a 
tendency  to  lie  in  long  irregular  patches,  parallel  to  the  lining,  while 
the  iridescent  spots  form  groups  in  short  lines.   ' 

The  peculiar  appearance  of  some  of  the  masses  of  felspar  appears 
to  be  due  to  opaque,  subtranslucent  and  translucent  particles  that  are 
irregularly  associated  together.     In  one  mass  was  observed  what  seems 


Kin  A  HAN — On  Microscojncal  8t  nurture  of  Bocks.  97 

to  be  small  gas  bubbles  of  the  same  class  as  those  mentioned  when 
describing  the  fleBh-eoloured  orthoclase,  bnt  in  no  other  of  the  masses 
could  they  be  detected,  and  they  do  not  appear  to  affect  the  structure 
of  the  mineral.  Very  few  inlying  minerals  were  observed  in  this 
felspar,  the  most  marked  being  minute  blebs  of  quartz,  and  black 
specks  that  may  be  pyrite  or  magnetite.  This  felspar  is  evidently  one 
of  the  orthoclases,  probably  adularia. 

Greenish  waxy  fehpar  (Oligoclase  ?). — ^This  triclinic  felspar  is  not 
very  well  represented  in  either  of  the  slices  that  were  cut  from  the 
specimen  of  the  Knockanavoddy  granite,  as  in  one  it  scarcely  appears, 
while  in  the  other  only  portions  of  crystals  occur ;  but  in  other  places 
in  the  neighbouring  rock  we  know  it  was  more  frequent.  This  felspar 
we  suppose  to  be  oligoclase,  and  we  will,  therefore,  ^rst  describe  the 
appearance  of  oligoclase  from  Ytterby,  Sweden  (F.  Kutley).  A  slice  of 
the  latter  mineral  under  the  low  power  (42)  is  found  to  have  originally 
consiBted  of  regular  lines  of  darkish  and  light  colours,  which  are  now 
broken  up  by  long  but  irregular  spaces,  that  appear  to  have  been  due 
to  shrinkage  fissures  after  the  mineral  was  formed,  while  scattered 
about  are  inlying  crystals,  blebs,  and  particles  of  quartz  and  small 
opaque  specks  (fig.  9,  PL  7).  In  fig.  10,  PI.  7,  is  represented  por- 
tions of  the  green  waxy  felspar  of  the  Knockanavoddy  granite.  In  them 
the  riband  of  colour  is  well  developed  which  gives  a  vivid  change  of 
colour  when  the  polarizer  is  turned,  especially  if  viewed  through  a 
plate  of  selenite ;  at  (a)  are  irregular !flake8  of  mica,  at  {h)  a  crystal  that 
appears  to  be  titanite,  as  it  is  similar  to  a  large  crystal,  part  of  which, 
with  two  inliers  of  the  same  mineral,  is  represented  in  fig.  11,  while 
at  (r)  a  portion  of  a  roimdish  but  irregular  mass  of  felspar  (orthoclase  ?) 
appears.  When  the  riband  at  {d)  (fig.  10)  is  magnifi^  (386)  the 
mineral  is  found  to  be  in  places  full  of  minute  cavities,  some  round, 
others  vermicular  and  sinuose,  while  the  rest  have  irregular  forms.  In 
places  these  occur  in  lines  parallel  to  the  riband,  but  the  mass  of  them 
cross  it  in  clouds  and,  therefore,  can  have  no  connexion  with  the 
structure  of  the  rock  as  seen  with  the  low  power  (42),  but  to  the 
clouds  crossing  the  structure,  may  be  due  the  faint  transverse  play  of 
colours.  The  oligoclase  from  Ytterby,  when  viewed  under  the  high 
power  (386),  is  also  found  to  be  affected  by  sioiilar  cavities,  but  in  it 
they  have  a  tendency  to  run  in  lines  parallel  to  the  riband.  These 
cavities  appear  to  be  due  to  minute  gas  bubbles  attached  to  the  sides 
of  minute  vacancies,  and  these  cavities  in  the  Swedish  specimens  are 
in  general,  but  not  always,  nearly  parallel  to  the  riband,  while  in  the 
Knockanavoddy  granite  they  run  very  irregularly. 

B.*  Porphyritic  granite  from  Ballynahown  (Ualway  sheet  93). — This 
rook,  when  examined  in  the  field,  seemed  to  consist  of  flesh-coloured 
felspar,  dull  or  olive  green  felspar,  quartz,  black  mica,  amphibole, 
pyrite,  and  white  mica.  The  flesh-coloured  felspar  appears  principally 
in  large  crystals,  often  twins,  which  are  imbedded  in  a  matrix  princi- 
pally made  up  of  the  green  felspar  and  the  quartz.  Most  of  the 
amphibole,  black  mica,  and  pyrite  are  associated  together  in  nests, 


98  Proceedbujs  of  the  Royal  Irish  Academy, 

while  the  white  mica  occnrs  in  minute  spangles.     In  places  in  this 
rock  are  isolated  crystals  of  titanite. 

Of  this  rock  only  one  slice  was  cut,  heing  taken  from  a  portion 
showing  the  ordinary  appearance  of  the  rock  in  which  the  dull  green 
felspar  predominated.  This  mineral  was  very  similar  in  aspect  to  the 
greenish  waxy  felspar  of  the  Knockanavoddy  granite  (B.*).  However, 
on  heing  placed  under  the  low  jwwer  of  the  microscope  (42),  it  was 
found  that  the  colour  and  appearance  in  the  field  were  deceptive,  as  the 
mineral  now  presented  characters  similar  to  those  found  in  the  dull 
white  felspar  of  the  Knockanavoddy  rock  (figs.  7  and  8,  PL  7),  while 
mixed  up  with  it,  although  not  detected  in  the  field,  was  a  tri- 
clinic  felspar,  and  associated  with  them  a  few  small  crystals  and  masses 
of  flesh-coloured  orthoclase.  Here  also  as  in  the  Knockanavoddy  rock, 
most  of  the  mica,  amphihole,  and  pyrite  occur  associated  together, 
while  the  mass  of  the  quartz  forms  the  skeleton  of  the  rock.  !No  titan- 
ite occurs  in  the  slice. 

Flesh-coloured  felspar  (Orthoclase). — None  of  the  large  crystals  were 
'  examined  hut  the  small  crystals  and  masses  showed  exactly  similar 
characters  to  those  found  in  the  small  crystals  examined  in  the  Knock- 
anavoddy granite  (fig.  6,  PI.  7). 

Dull  green  soapy  felspar  (Adularia  ?). — This  mineral  gives  the  cha- 
racter described  for  the  dull  white  felspar  of  the  Knockanavoddy  rock, 
and  in  it  are  found  portions  of  crystals  and  small  masses  that  show  the 
ribands  of  colour  characteristic  of  the  tricUoic  felspars. 

Driclinic  felspar, — This  occurs  in  a  few  isolated  masses,  and  as  parts 
of  crystals  in  or  associated  with  the  adularia  (?),  the  structures  they  dis- 
played being  very  similar  to  those  already  described  as  characterizing 
the  triclinic  felspar  of  the  Knockanavoddy  granite. 

B.'  and  B.*  -4  slightly  foliated  porphyritic  granite, — This  rock  was 
collected  by  the  late  Mr.  tfukes,  and  is  marked  from  Furbogh  (Galway). 
It  is  similar  to  the  rocks  in  situ  on  the  S.  E.  and  S.  W.  of  Furbogh 
demesne.  In  the  rock,  the  most  conspicuous  constituent  is  the  flesh- 
coloured  felspar,  the  large  crystals  of  which  give  the  porphyritic 
character  to  the  rock,  but  the  principal  constituents  are  the  dull  white 
and  waxy  greenish  felspars  and  black  mica ;  irregular  leates  of  the 
latter  associated  with  amphihole,  giving  the  foliated  structure  to  the 
rock.  There  are  also  present  quartz,  white  mica,  and  pyrite,  with 
thinly  disseminated  crystals  of  titanite.  At  Furbogh  it  was  observed 
in  the  field  that  some  of  the  large  flesh-coloured  crystals  had  an  envelope 
of  dull  white  felspar. 

Of  this  rock  two  slices  were  cut,  one  containing  a  portion  of  one 
of  the  large  flesh-coloured  orthoclase  crystals,  and  the  other  being  from 
a  portion  showing  the  ordinary  character  of  the  rock.  In  both  the  dif- 
ferent felspars  are  represented. 

Flesh-coloured  felspar, — The  large  crystals,  as  in  the  Knockanavoddy 
rock,  are  generally  twins,  and  in  the  slice  that  was  cut  through  one  of 
them,  the  junction  between  the  twins  is  a  sharp  line  not  an  irregular 
vacancy  as   was  dcscribwl   in    connexion   with   the   Knockanavoddy 


EiNAHAN — On  MUroscapical  Stmcfure  of  Rocks,  99 

p-anite.  These  large  crystals,  as  in  the  Knockanavoddy  rock,  contain 
many  inlying  minerals,  those  most  conspicuous  being  quartz  and 
pyrite ;  while  the  characters  of  the  small  crystals  and  masses  of  the 
flesh-coloured  felspar,  as  in  both  the  rocks  previously  described  (B.' 
and  B.*),  are  very  regular  and  similar  to  those  already  figured  and 
described  (fig.  6,  PI.  7),  and  contain  very  few  inlying  minerals.  All 
these,  however,  in  this  and  the  other  granites  according  to  the  portion 
of  the  crystal  exposed  to  view  give  remarkable  changes  of  colour. 

Ihdl  white  feUpar  ( Adularia  ?). — This  felspar  when  examined  is 
similar  in  structure  to  the  dull  white  felspar  of  the  Knockanavoddy 
granite  and  the  dull  green  soapy  felspar  of  the  Ballynahown  rock. 
In  one  of  these  crystals  that  had  a  lined  structure  when  viewed  with 
a  power  of  386,  the  lining  appears  to  be  due  to  broken  and  more  or 
less  irregular  walls  of  quartz,  that  give  shades  of  violet  when  the 
intervening  spaces  appear  a  translucent  yellowish  white,  that  had 
inliers  consisting  of  irregular  large  white  spots,  minute  black  specks, 
and  long  black  crystals.  A  group  of  crystals  of  felspars  in  one  of  the 
slices  (B*)  under  a  low  power  (42)  appear  to  be  similarly  constituted, 
but  each  had  a  character  of  its  own  when  viewed  with  a  power  of  238 
(fig.  12,  PI.  7).  The  upper  crystal  on  the  right  hand  is  of  the 
ordinary  character  belonging  to  tbis  dull  white  felspar,  being  more  or 
less  opaque,  and  spotted  over  with  iridescent  particles.  The  crystal  to 
the  left  hand  has  an  irregular  lining,  somewhat  similar  to  that  just 
now  described,  consisting  of  walls  of  quartz  separating  whitish  BX)otted 
portions,  except  that  the  quartz  walls  are  thicker  and  more  con- 
spicuous than  the  intervening  portions  ;  while  the  lower  crystal  to  the 
right  hand  is  traversed  by  minute  dark  parallel  lines,  that  in  places  in 
the  lower  portion  of  the  crystal  are  associated  with  partial  walls  of 
quartz,  all  being  crossed  somewhat  obliquely  by  newer  minute  parallel 
whitish  lines.  In  the  latter  crystal,  under  a  still  higher  power  (386), 
the  dark  nearly  horizontal  lines  are  found  to  be  principally  due  to  more 
or  less  regular  lines  of  probably  oblique  sections  of  minute  oval 
tubes  (fig.  13,  PI.  8),  with  which  are  associated  short  black  lines, 
that  seem  to  be  vacancies,  while  the  slightly  oblique  lines  crossing 
them  appear  to  have  been  shrinkage  fissures  that  subsequently  were 
filled  by  some  white  substance.  All  these  crystals  seem  to  be  the  same 
felspar,  with  different  appearances,  due  to  different  structures. 

The  trielinic  felspar  (Oligoclase  ?). — This  felspar  in  these  slices  is 
always  more  or  less  associated  with  the  dull  white  felspar,  but  in  the 
slice  with  the  twin  crystal  of  orthoclase  (B*),  there  are  some  good 
exposures  of  crystals  and  irregular  masses,  which  change  from  faint 
rilondB  of  shades  of  grey  and  yellowish  grey,  to  shades  of  violet, 
purple,  and  blue.  Pig.  14,  PI.  8,  represents  a  portion  of  one  of  these 
crystals  under  a  power  of  238.  These  crystals  contain  little  black 
inliers  (pyrite  ?)  while  scattered  through  the  oligoclase  (?)  are  other 
similar  black  crystals.  In  one  place  in  this  slice  (B*),  under  a  power 
of  196,  was  detected  a  mass  having  a  peculiar  structure,  as  the  riband 
takes  an  irregular  semi-radiating  form,   in  places  being  somewhat 


100  Proceedings  of  the  Royal  Irinh  Academy, 

plumose  (fig.  15,  PI.  B).  As  the  power  is  increased  it  becomes 
evident  that  the  appearance  is  due  to  five  crystals  being  tangled  up 
together ;  and  with  a  power  of  296  the  ribands  appear  to  be  regular, 
the  curled  aspect  being  due  in  part  to  refraction  at  the  junctions  of 
the  crystals.  Under  a  power  of  386  the  whole  is  seen  dotted  over  with 
minute  black  specks,  with  some  short  black  lines  ;  the  specks  in  some 
places  being  more  numerous  than  in  others  (fig.  16,  PL  8).  Some  of 
these  specks,  especially  those  in  the  upper  crystal,  are  evidently  gas 
bubbles,  but  more  than  three-fourths  in  the  whole  mass  seem  to  be 
minute  crystals  or  bunches  of  crystals. 

Fig.  17,  PI.  8,  represents  another  crystal,  showing  under  a  power 
of  296,  a  somewhat  similar  construction.  In  the  upper  portion  the 
layers  are  slightly  crumpled  and  crushed  up,  especially  the  lower  ones. 
In  the  small  portion  to  the  left  hand  the  lamina  run  obliquely,  while 
in  the  crystal  to  the  right  hand  there  was  seen  by  polarized  light,  a 
whitish  mass  traversed  most  irregularly  by  blue  walls  and  roundish 
masses.  Under  a  higher  power  (386)  the  composition  of  the  upper  and 
left  hand  crystals  seem  similar  to  that  of  the  five  just  described,  the 
mass  being  cdl  dotted  over  with  black  specks  and  gas  bubbles;  and  the 
irregular  mass  to  the  right  hand  seems  to  be  incHned  to  have  a  con- 
centric structure. 

B*.  Porphyritic  granite — Kirkullen  (Galway  sheet  81).  In  the 
field  it  seems  to  contain  flesh-coloured  felspar,  light  green  waxy 
felspar,  quartz,  amphibole,  black  mica,  pyrite,  small  spangles  of  white 
mica ;  ciystals  of  titanite  are  rare.  The  flesh-coloured  and  the  light 
green  felspars  seem  to  occur  in  about  equal  quantities,  but  large, 
usually  twin  crystals  of  the  first,  give  the  porphyritic  character  to 
the  rock  mass,  but  some  of  the  light  green  felspar  crystals  axe  large 
also.  The  micas,  amphibole,  and  pyrites,  occur  in  nests  usually 
associated  with  the  quartz  skeleton,  but  the  micas  also  occur  margining 
some  of  the  crystals  of  the  green  felspar. 

Of  this  rock  one  slice  was  cut  showing  its  ordinary  character,  and 
from  it  we  learn  there  are  at  least  three  kinds  of  felspar  in  the  rock, 
although  only  two  were  observed  in  the  field. 

Flesh-coloured  fehpar  (Orthoclase).  None  of  the  large  crystals  were 
examined,  but  the  small  crystals  and  masses  seem  to  be  quite  diflerent 
from  those  observed  in  the  previously  examined  rock  (B',  B',  B',  and  B*), 
as  they  contain  numerous  inlying  minerals,  similar  to  the  twin  crystals 
in  the  Knockanavoddy  (B')  and  Eurbogh  (B*  and  B*)  granites. 

Pale  greenish  felspar.  This,  as  it  appeared  in  the  field,  seemed  to 
be  similar  to  the  greenish  waxy  felspar  of  the  Knockanavoddy  granite, 
but  under  the  microscope  we  find  the  mass  of  it  has  characters  similar 
to  those  of  the  dull  white  felspar  of  that  rock,  but  with  it  are 
associated  crystals  and  portions  of  crystals  of  a  triclmic  felspar.  Under 
a  power  of  63,  one  crystal  of  this  kind  of  felspar  was  found  to  be 
enveloped  in  triclinic  felspar,  and  another  crystal  has  a  centre  and 
semi-envelope  of  triclinic  felspar,  while  enclosed  portions  of  crystals  of 
triclinic  felspar  are  not  uncommon.     Many  of  the  crystals  and  masses  of 


KiNAHAN — On  Microscopical  Structure  of  Rocks,         101 

this  felspar  are  so  opaque  that  their  structure  cannot  be  properly  seen; 
this  is  probably  due  to  the  slice  not  being  cut  thin  enough.  Enough, 
however,  can  be  seen  to  know  that  the  felspar  is  similar  to  those  pre- 
viously described  and  supposed  to  be  adulana. 

TricUnic  fehpar.  This  felspar,  when  the  rock  was  examined  in 
the  field,  could  not  be  distinguished  from  the  preceding.  In  the 
portions  of  the  crystals  associated  with  the  aduiaria  (?)  the  lines  of 
structure  are  straight  and  parallel,  and  the  play  of  colour  regular,  but 
this  is  not  the  case  in  the  individual  crystals  and  masses.  In  one 
crystal,  with  a  power  of  196,  there  are  straight,  sharp,  but  not  per- 
fectly parallel,  lines,  while  the  play  of  colours  is  faint.  Under 
a  power  of  396  the  straight  sharp  lines  seem  to  be  due  to  cleavage 
or  shrinkage  lines,  and  are  now  filled  by  thin  films  of  a  black 
mineral ;  they  probably  are  accidental  adjuncts  to  the  crystal.  In  a 
second  mass  of  triclinic  felspar  we  find,  with  a  power  of  196,  that  the 
layers  of  structure  are  not  parallel,  some  being  inclined  to  be  lenticular, 
the  lines  of  green  and  white  being  short,  of  different  thicknesses,  or 
joining  into  one  another ;  yet  the  play  of  colour  is  very  regular. 


R.  I.  A.  PROC,  8BR.  II.,  VOL.  II.,  SCIRNCK. 


102  Proceedings  of  the  Royal  Irish  Academy. 


XVII. — Geakitic  awd  otheb  Ingeiote  Bocks  op  YAB-CoinrAiroHT,  aih) 

THE   LOWEE  OWLE ;   OE  THE   M0lTin:AXN0U8  TEA.CT  OP  COXTNTEY  WEST   OP 

Loughs  Mask  and  Coeeib.     By  G.  Henet  Ejitahak,  M.  B.  I.  A., 
F.  B.  G.  8. 1.,  &c.,  with  Plates  9,  10,  11  and  12. 

[Bead  November  13,  1871].* 

Object  of  ths  JEssay, 

DuEn^G  an  examination  extending  over  seven  years  on  the  part  of 
the  Irish  hranch  of  the  Geological  Survey  of  the  United  Kingdom, 
of  the  rocks  in  the  mountainous  country  west  of  Loughs  Mask  and 
Corrih  (parts  of  the  counties  Mayo  and  Galway),  certain  facts  as  to 
their  age,  position,  and  relations  to  one  another  were  gradually 
developed,  and  certain  convictions  as  to  their  origin  formed. 

In  this  paper  it  is  proposed  to  lay  tefore  the  Academy  an  epitome 
of  the  facts  ohserved  ;f  aiso  some  suggestions  in  regard  to  the  origin  of 
the  granites  and  other  ingcnite  rocks.  J 

The  latter  are  specially  put  forward  in  the  hope  that  they  may  be 
examined  and  criticised  by  more  competent  judges  than  the  author,  and 
thereby  their  value  proved. 

In  the  first  part  of  the  paper  it  is  proposed  to  enumerate  and  give 
a  general  description  of  the  rocks ;  while  in  the  second  part  will  be 
found  suggestions  to  account  for  their  origin  and  relations  one  to  the 
other. 


*  The  publication  of  this  paper  has  unavoidably  been  delayed  by  the  MSS. 
having  been  mislaid  after  it  was  referred  to  Council  for  publication. 

t  The  details  relating  to  these  rocks  will  be  found  in  the  published  memoiiB  of 
the  Irish  branch  of  the  Geological  Survey. 

X  Mr.  D.  Forbes  has  proposed  to  divide  all  rocks  into  two  great  classes.  First, 
Ingcnite  rocks  (bom,  bred,  or  created  within  or  below) ;  and  second,  Derivate  rockt. 
**  since  directiy  or  indirectly  they  are  all  derived  from  the  destruction  of  the  former. 
(The  Microscope  in  Ocology^  by  David  Forbes,  F.  R.  S.,  pase  6),  reprinted  from 
the  Popular  Science  Review,  October,  1867.  In  the  first  are  included  all 
granitic,  metamorphic  and  igneous  rocks,  while  the  second  contains  all  sedimentary 
and  other  subaqueous  or  subaerial  accumulations.  The  geological  terms  neces- 
sary for  a  description  of  the  ingenite  rocks  have  been  used  by  some  authors  in 
most  conflicting  senses,  while  many  rock-names  are  unintelligible  on  account  of 
their  being  given  by  the  many  writers  to  rocks  of  different  characters.  In  this 
e^esy  all  words  of  one  class  will  have  the  same  signification.  Thus,  words  ending 
in  ie  or  ose,  will  signify  *  belonging  to' ;  as.  Granitic,  belonging  to  granite ;  Schistose^ 
belonging  to  schist ;  and  words  ending  in  oid  will  signify  *■  like ' ;  as  granitoid, 
granite-like  ;  gneiasoidy  gneiss-like,  &c.  Rock-names,  except  when  absolut^y 
objectionable,  wiU  be  used  for  the  rocks  to  which  thoy  were  originally  given,  but  at 
the  same  time,  to  prevent  confusion,  the  ordinary  composition  of  the  rock  will  be 
stated.  Dana's  suggestion  for  an  ending  of  yte  instead  of  ite  for  rock-names  will 
be  adopted,  also  his  name  for  minerals. 


KiNAHAN — On  Granitic  and  other  Ingenite  Rocks,         103 

PabtI. 

Boch-names  and  general  deecription. 

The  ingeidte  rocks  of  this  axea  include  Plutonic  rocke  (Basic  and 
highly  Siliceous) ;  Metamarphie  rocks  (Sedimentary  and  Igneous),  and 
Granitic  rocks. 

General  Table  of  the  Bocks, 

Pltjtonic  Bocks. — Carboniferous  (?)  Whinstonss ;  Post-silurian 
Whinstones ;  Llandovery  Whindstones ;  Pre-Llandovery  Whinstones  ; 
Camhro-silurian  (?)  Whinstones  (Metamorphic)  ;  Post-silurian  Fel- 
stones;  Silurian  Felstones  (Llandovery  age) ;  Pre- Llandovery FelsUmes  ; 
Cambro-silurian  (?)  Felstones  (usually  Metamorphic). 

Metamorphic  Bocss. — Schist ^  including  schistose-limestone,  schis- 
tose-dolomyte,  ophyte,  and  steatyte ;  Gneiss;  Hornblende  rock*  (meta- 
morphic whinstone) ;,  Foliated  Felstone  or  Gneissyte  and  Granitoid 
FelsUme  (metamorphic  felstone). 

Gea>'itic  Rocks. — Ekanyte  or  Qmrtz  Porphyry  ;  Oligoclasic^  Gra- 
nite; Orthoclasic  or  Highly  Siliceous  Granite, 

Pltttonic  Rocks.  J — In  the  foregoing  list  the  oldest  whinstones  and 
felstones,  except  a  few  of  the  latter,  are  more  or  less  metamorphosed ; 
consequently  tiey  do  not  now  helong  to  the  plutonic  rocks  and  cannot 
he  descrihed  among  them,  hut  their  descriptions  will  he  found  among 
the  metamorphic  rocks,  under  the  names,  Hornblende  rock,  Gneissyte^ 
and  Granitoid  Felstone.  They  are  enumerated  in  the  list  to  show 
their  age  and  origin. 

Whinstones, — The  term  whinstone  is  here  used  in  preference  to 
greenstone  on  account  of  the  varied  significations  given  to  the  latter. 
Naumann  confines  the  name  to  diahase ;  Brongniart  to  dioryte  (amphi- 
bole  +  felspar,  not  orthoclase) ;  Cotta  includes  in  his  greenstone  group, 
diahase  and  dioryte ;  while  Jukes  and  many  other  British  geologists 
included  not  only  all  the  hasic-plutonic  rocks  or  whinstones  hut  also 
many  of  the  hasic  felstones  (Eurytes  of  Dauhuisson),  especially  if  the 
latter  are  of  a  green  colour. 

Pre-Llandovery  Whinstone, — These  rocks  seem  principally  if  not 
wholly  to  helong  to  the  group  of  rocks  that  are  included  under  the 
general  name  of  diabase  [pyroxene  (diallage  generally)  +  felspar  (not 


*  This  term  is  used  as  Macculloch  used  it. 

t  These  granites  were  originally  called  oligoclasic  granites,  as  the  wax^  felspar 
was  supposed  to  be  oligoclase ;  now,  however,  by  microscopical  examination,  it  is 
found  to  be  in  part  orthoclase,  probably  adularia.  The  names,  however,  may  still 
stand,  as  oUgoclase  seems  to  be  an  essential  element  of  the  rocks,  ^hile  it  is  rare 
in  the  orthoclasic  granite.     [Note  while  in  press.'] 

X  From  Plutus^  the  god  <m  the  infernal  or  lower  regions,  the  name  having  beim 
given  to  these  rocks  in  contradistinction  to  the  volcanic  rocks  or  those  formed  at  or 
near  the  present  surface  of  the  earth. 


104  Proceedings  of  the  Royal  Irish  Academy, 

orthoclase)  +  ripidolite].  They  are  light  greenish  or  purpKsh  to  bright 
green  in  colour ;  tough  but  weather  more  or  less  freely  ;  generally  have 
a  scaly  or  mealy  aspect ;  some,  however,  are  compact  {diahase-aphanyte). 
They  break  with  an  uneven  to  a  subhackly  fracture,  and  fuse  more  or 
less  readily  before  the  blowpipe.  Some  diabase  is  magnetic,  due  to  the 
rock  containing  pyrrhotite  as  an  essential  (maynetio  or  pyrrhotitic 
diabase) ;  a  common  variety  is  highly  micaceous  {mtcaeeous-diahase)^  while 
others  are  both  micaceous  and  pyritic,  the  latter  often  weathering  into 
a  mica-ferruginous  sand  which  may  be  magnetic. 

Llandovery  WhinsUme, — Bedded  dolorytes  in  the  Toormakeady  con- 
glomerates. 

Post'Silurian  W^tnstone. — Some  of  these  rocks  apparently  are  very 
similar  to  the  diabase  already  described,  while  in  others  uralite  replaces 
the  diallage  {uralitic'diahase).  Some  of  the  uralitic-diabase  seems  in 
places  to  graduate  into  a  rock  apparently  a  euryte  or  basic  felstone. 

Carhontferous  (?)  Whinstone. — ^The  age  of  these  rocks  has  not  been 
positively  proved,*  nevertheless,  it  is  evident  that  they  are  newer  than 
the  rock  just  described,  as  in  all  places  where  rocks  of  both  groups  are 
associated  together  the  diabase  is  displaced  and  cut  by  these  whinstones ; 
moreover,  they  seem  to  be  newer  than  all  the  felstones.  They  are 
dolerytes,  probably  melaphyres  [pyroxene  +  felspar  (not  orthoclase)  with 
or  without  some  amphibole].  These  dolerytes  are  from  granular  to 
compact,  have  a  glistering  resinous  lustre,  are  dark-coloured  (blackish, 
blackish-brown,  and  dark  olive),  and  tough.  The  compact,  homo- 
geneous varieties  {melaphyre-aphanyte)  have  a  conchoidal  fracture, 
while  the  granular  rocks  break  from  uneven  to  subhackly.  Some 
of  the  melaphyres  are  porphyritic,  while  others  are  more  or  less 
micaceous  {micaceous-melaphyre).  In  a  few  were  observed  sUiceous 
blebs  (opal  ?) ;  all  fuse  readily  before  the  blowpipe.  When  in  mass  the 
outside  shell  of  these  dolorytes  has  a  peculiar  tufPoid  aspect  and  con- 
tains few  or  many  zeolites.f  All  the  melaphyres,  but  especially  tho 
aphanytes,  usually  weather  freely,  the  latter  nearly  always  being  in 
narrow  dykes.  The  free  weathering  seems  in  part  due  to  the  structure 
of  the  rocks,  many  being  very  jointy,  causing  them  to  break  up  into  small 
angular  fragments.  This  reticulated  structure  appears  to  be  caused  by 
a  rude  columnar  structure  perpendicular  to,  and  a  platy  structure 
rudely  parallel  to  the  walls  of  the  dykes.  In  some  of  these  rocks  there 
is  a  spheroidal  structure  combined  with  the  platy  (fig.  B,  PL  9),  wliile 
in  others  the  fragments  into  which  the  rock  breaks,  are  found  to  con- 
sist of  consecutive  layers.  In  one  locality,  part  of  a  dyke  was  found  to 
be  amygdaloidal ;  this  structure  occurred  along  a  joint  in  the  dyke  (see 


♦  My  colleague,  R.  G.  Symes,  F.  R.  G.  S.  I.,  &c.,  &c.,  has  proved  that  whin- 
Btones  in  the  neighbourhood  of  Castlebar,  Co.  Mayo,  exactly  similar  to  those  now 
being  describetT,  are  of  carboniferous  age. 

t  Those  tiLffoid  portions  may  be  due  to  the  rock  mass  being  protruded  into 
water ;  consequently,  the  outer  part  would  be  liable  to  be  pulvensed  and  disinte- 
grated (see  page  113). 


KiNA'HAN — On  Granitic  and  other  Ingenite  Rocks.       106 

fig.  A,  PI.  9).  These  whinstone  dykes  often  ocour  associated  with  older 
intnisive  rocks,  coming  up  alongside  or  in  them,  on  which  account  in 
some  places  rocks  of  quite  different  ages  are  found  associated  together. 
A  wlunstone  in  a  granite  vein,  and  this  granite  vein  in  hornblende 
rock,  has  been  observed  in  various  places. 

Fehtonea  of  poat-silurian  age. — These  felstones  are  newer  than  the 
rocks  of  Llandovery  age ;  they  come  up  through  the  Silurian,  the  meta- 
morphic,  and  the  granitic  rocks.  They  are  blue,  greenish-blue,  or  grey 
in  colour,  from  compact  to  splintery,  often  more  or  less  granular,  and 
with  a  fracture  from  semicbnchoidal  to  uneven.  In  places  when 
traversing  certain  argillaceous  rock  there  are  no  walls  to  the  dykes,  the 
two  rocks  merging  into  one  another  as  if  the  adjoining  part  of  the 
derivate  rock  had  melted,  and  thereby  been  amalgamated  with  the  fel- 
stone.  Some,  if  not  aU,  these  rocks  belong  to  the  eurgtes  or  basic  fel- 
stones (one  of  the  hyhrid-rocks  of  Durocher),  as  splinters  fuse  on  the 
edge  before  the  blowpipe,  some  even  seeming  to  graduate  into  a 
unlitic-diabase.  Others  are  porphyritic  merging  into  porphyrite ;  the 
latter  more  generally  being  found  as  small  dykes  or  as  thin  portions 
alongside  the  walls  of  large  dykes.  In  the  latter  case  although  the 
major  portion  of  the  dyke  may  be  grey  or  green  in  colour,  splintery 
or  granular  in  texture,  and  breaking  with  an  uneven  fracture,  yet  a 
few  inches  in  thickness  alongside  the  walls  will  be  of  a  clear  blue 
colour  with  distinct  felspar  crystals  (a  porphyrite),  compact  and  break- 
ing with  a  conchoidal  or  subconchoidal  fracture.  Some  of  these  fel- 
stones are  so  jointy  that  they  break  up  into  an  angular  shingle  or 
gravel — ^in  some  there  is  a  platy  arrangement  parallel  or  nearly  so  to 
the  walls  of  the  dykes,  while  in  others  or  in  parts  of  others  there  is  an 
oblique  structure,  and  often  between  the  oblique  lines  are  others  per- 
pen^cular  to  them,  as  shown  in  fig.  C,  PI.  9.  At  or  near  the  ter- 
mination of  dykes  a  spheroidal  structure  is  common,  more  or  less 
combined  with  a  platy  arrangement. 

Felstones  of  upper  silurian  age  (Llandovery). — ^These  felstones  occur 
as  bedded  masses  among  the  rocks  of  upper  Llandovery  age  and  as  dykes 
in  the  granitic  and  other  hypogene  rocks.  Among  the  Llandovery  rock 
they  are  associated  with  ta&s^  agglomerates,  and  such  like  mechanical 
accompaniments;  in  places  the  basal-bed  of  the  Toormakeady  and 
Mweelrea  beds  is  one  of  these  felstones.  Among  the  hypogene  rocks 
the  dykes  sometimes  graduate  into  amphiholicrehanyte. 

These  rocks  are  usually  very  compact,  often  comoid;  some,  however, 
are  scorious  and  amygdaloidal ;  they  may  be  porphyritic  or  pass  into 
porphyrite.  In  places  when  in  bed-like  masses  they  have  a  columnar 
structure.  They  are  from  green  to  purple  in  colour ;  often  are  quartzitic, 
especially  the  purple  rocks,  containing  blebs,  globules,  and  crystals  of 
glassy  quartz  that  usually  have  a  dull  pellicle.  Before  the  blowpipe 
they  fuse  with  greater  or  less  facility,  the  purple  varieties  on  the  edges  of 
splinters,  but  some  of  the  green  rock  readily  into  a  bead.  All  the  green 
varieties  are  very  basic,  some  indeed  appearing  to  graduate  into  whin- 
stone.     One  variety  is  maculated,  roundish  and  oval  dark  blue  patches 


106  Proceedings  of  the  Royal  Irish  Academy  t 

occurring  in  a  light  purplish  blue  matrix ;  these  maculse  decompose 
freely,  and  give  the  weathered  surface  of  the  rock  an  irregular  honey- 
comb aspect ;  they  also  fuse  easily  before  the  blowpipe,  but  the  matrix 
only  slightly  on  the  edges  of  splinters.  There  is  sdso  a  variolitic  green- 
ish variety,  dark  green  small  concretions  in  a  light  green  base ;  this 
rock  is  very  friable  and  possibly  may  be  a  compact  tuff  and  not  a  nor- 
mal igneous  rock.  All  these  felstones  are  basic  varieties,  the  eurytes  of 
Daubuisson.*  In  some  of  the  dykes  of  micaceous-euryte  there  is  a  fine 
platy  structure  that  unless  carefully  examined  may  be  mistaken  for 
foliation.  In  different  places  in  this  area,  but  very  numerous  in  the 
west  part  of  the  barony  of  Ballynahinch,  are  dykes  of  basic-elvanyte  ; 
these  in  places  seem  to  graduate  into  these  eurytes,  and  probably  were 
the  roots  or  deep-seated  portions  of  the  upper  silurian  felstones. 

Pre-Llandovery  felstones. — The  rocks  of  this  age  only  occur  as  dykes 
and  intrusive  masses  in  the  hypogene  rocks.  Por  the  most  part  they 
seem  to  he  petro-silex  or  the  rocks  called /<?/«y^  by  Dana,  Cotta,  Forbes, 
and  others.  Some  are  comoid,  others  saccharoid  in  appearance ; 
usually  the  constituent  are  undeveloped,  save  the  quartz,  which  appears 
in  some  as  blebs,  globules,  and  crystal  often  very  minute  {quartzitic- 
petrO'Silex),  Some  of  the  saccharoid  varieties  graduate  into  a  rock  very 
similar  in  aspect  to  the  felsitic-granite  described  hereafter.  Either 
kinds  may  become  porphyritic  and  micaceous,  and  through  that  graduate 
into  elvanyte.  In  some  of  the  comoid  petro-silex  there  is  a  riban  of 
different  colours  or  of  dark  and  light  shades  of  one  colour  {rihan  petro- 
silex)y  while  along  the  riban  the  rock  has  a  tendency  to  split  into 
plates  or  slabs ;  these  rocks  are  often  quartzitic.  A  common  variety  of 
petro-silex  is  of  a  whitish  pink,  greenish  blue  or  greyish  colour,  sub- 
translucent,  homogeneous,  compact,  breaking  with  a  conchoidal  fracture, 
and  weathering  with  a  thick  white  crust.  This  variety,  although  com- 
pact, is  often  effected  by  three  or  more  systems  of  close  jointing  that 
cause  it  to  break  up  into  angular  shingle,  often  partaking  more  or  less 
of  a  cubical  form.  When  not  jointed  this  variety  weathers  with  a  remark- 
able smooth  even  surface. 

CamhrO'Silur tan  felstones. — In  the  country  north  of  KiUary  HarbourJ 
associated  with  partially  metamorphosed  sedimentary  rocks  are  fel- 
stones (also  in  places  partly  altered)  occurring  in  protrusions  and  in 
dykes.  The  rock  when  unweathered  is  usually  of  a  bright  green 
or  grey  colour ;  it,  however,  weathers  easily  into  a  dirty  cream-coloured 
rotten  rock.  In  the  dykes  this  felstone  often  has  a  peculiar  brcciated 
structure  having  an  appearance  more  like  a  coarse  tuff  or  a  fault-rock 
than  a  normal  felstone ;  nevertheless,  in  other  parts  its  true  character  is 


♦  Naumann  and  Cotta  propose  to  call  these  varieties  Porphyrites.  It,  however, 
is  a  moet  inappropriate  and  confusing  name ;  for  in  the  first  place,  as  Cotta  himself 
points  out,  ^^the  name  of  porphyrite  refer*  to  a  texture  which  is  not  an  essential 
feature  of  these  rocks,  because  the  porphyrites  are  not  always  in  fad  porphyritic  ;" 
and  in  the  second  place,  porphjrite  and  porphjT^-  are  used  synonymously  by  many 
petrologists,  Cotta  even  so  using  it. 


KiNAHAN — On  Oranitic  atid  other  Ingenite  Rocks,  107 

indisputable.  When  in  piotnision  a  considerable  portion  of  the  mass 
will  be  a  scaly  or  mealy,  fnable,  tuffoid  rock ;  some  parts,  however, 
will  be  compact,  and  all  will  be  more  or  less  unctuous  as  if  the  rock 
•was  merging  into  steatyte.  These  rocks  must  be  very  ancient  compared 
with  the  rocks  last  described,  as  they  were  intruded  prior  to  the  meta- 
morphism  of  the  associated  rocks. 

Htpooene  Eocks. — The  hypogene  rocks  include  the  metamorphic 
and  granitic  rocks  given  in  the  general  table.  In  the  country  west  of 
Loughs  Mask  and  Corrib  the  development  of  these  different  rocks  is 
well  shown,  as  normal  sedimentary,  or  derivate  rocks  first  become 
partially  metamorphosed  {nckiat  series) ;  secondly,  the  alteration  becomes 
more  decided  (jneiss  series) ;  and  thirdly,  they  are  entirely  changed 
{metamorphic  and  intrusive  granite).  Intervening  between  the 
t3rpical  granites  and  the  plutonic  rocks  are  found  the  elvtmytes.  It 
has  previously  been  shown  that  the  plutonic  rocks  graduate  into 
elvanyte  and  hereafter  it  will  be  pointed  out  that  the  latter  rocks 
graduate  into  the  intrusive  granite,  and  through  that  into  the  meta- 
morphic granite.  The  rocks  composing  the  schist-series  are  for  the 
most  part  schist ;  nevertheless,  in  them  are  subordinate  beds  of  gneiss, 
on  account  of  some  rocks  being  more  susceptible  of  change  than  others, 
while  in  others  the  constituents  of  gneiss  (quartz  +  mica  +  felspar  or 
felsite*)  already  existed.  The  latter,  however,  are  seldom  typical 
gneiss,  that  is,  having  these  constituents  arranged  in  leaves  or  plates, 
but  rather  the  minerals  are  more  or  less  irregularly  mixed  together, 
only  an  incipient  foliation  being  developed.  Similarly  in  the  gneiss- 
series  there  are  subordinate  beds  of  schist,  as  some  rocks  on  account  of 
their  constituents  are  less  susceptible  of  change  than  others ;  while 
associated  with  the  rocks  of  both  the  schist  and  gneiss-series  are  meta- 
morphosed igneous  rocks. 

When  the  rocks  begin  to  be  altered,  the  planes  of  the  most  marked 
structure  in  the  original  rock  are  more  or  less  glazed  or  micacised,  and 
the  mass  indurated.  In  argillaceous  rocks  the  surfaces  of  joint  lines, 
breaks,  or  fissures  are  hardened  and  in  some  cases  these,  originally  open 
lines,  are  sealed;  or  the  sides,  varying  from  a  film  to  two  or  three  inches 
in  width,  are  luoxiened,  seemingly  by  being  impregnated  with  some  such 
substance  as  silex  in  solution.  On  the  surfaces  of  some  rocks,  crystal- 
line lines  about  the  size  of  whipcord  form,  sometimes  straight  but  often 
vermicular ;  moreover,  such  minerals  as  phylite,  chiastolite,  pyrite,  and 
the  like,  are  developed  indiscriminately  through  the  mass  of  the  rock  or 
on  the  structural  planes,  being  most  conspicuous  under  the  latter  cir- 
cumstance. A  primary  change,  prevalent  in  arenaceous  rocks,  is  a  more 
or  less  scaly  or  fissile  structure  being  developed,  while  others  become 
variolitic  or  maculated,  all  being  more  or  less  indurated  and  glazed  on 


*  Felsite  ib  the  mineral,  an  amalgamate  of  felspar  and  silex,  while  the  rock  will 
be  called  FeUyte. 


108  Proceedings  of  the  Royal  Irish  Academy. 

the  stractaral  planes.*  Gradually  the  rock  becomes  typical  schist,  when 
in  some  of  the  micasyte,  talco-micasyte,  and  talc-yte,  a  peculiar 
frilled  or  sharply  crumpled  struction  is  developed.  This  structure 
is  Very  remarkable,  as  no  structure  similar  to  it  occurs  in  the  unaltered 
rocks.  Moreover,  it  seems  to  disappear  in  the  last  stage  of  meta- 
morphism  as  it  has  not  been  remark^  in  any  of  the  rocks  of  the  gneiss- 
series.  In  some  of  the  quartzytes  or  quartz-schist  there  is  also  a 
peculiar  structure,  having  an  aspect  scarcely  distinguishable  from  the 
planed,  polished,  and  etched  surfaces  due  to  ice  action.  This,  how- 
ever, always  occurs  only  on  the  original  planes  of  stratification,  and 
if  the  rock  is  flaggy  and  is  split  into  plates  Ihe  surface  of  each  plate 
will  be  a  counterpart  of  that  above  it,  from  which  it  would  appear  this 
structure  is  prolMibly  due  to  a  cleavago  in  the  original  rock.  If  this 
was  the  case  all  other  traces  of  the  okavage  have  now  disappeared,  as 
the  present  rock  has  no  tendency  to  split  except  along  the  planes  of 
deposition. 

The  schists  graduate  into  gneiss  and  the  gceiss  through  granitoid- 
gneiss  or  gneissoid-granite  into  typical  granite. 

The  granitoid-gneiss  has  a  foliation  peculiar  to  itself.  In  all 
the  other  rocks  belonging  to  both  the  schist  and  the  gneiss  series  the 
foliation  appears  always  to  follow  the  most  prominent  structure  in  the 
original  rock,  let  it  be  fine- jointing,  cleavage,  or  lamination,  whei^er 
the  latter  is  parallel,  'oblique,  curled,  spheroidal,  concretionary, 
nodular,    or  conglomeritic.f      In   granitoid-gneiss   other  laws  seem 


*  The  partially  altered  grits  and  sandstone  called  by  Macculloch  "  Primary 
Sandstone/  {A  Oeologieal  Classification  of  Rocks^  ^r.,  by  John  Macculloch,  M.  D., 
F.  R.  S.,  &c.,  page  331),  are  largely  sepresented  in  the  country  west  of  the  northern 
end  of  Lough  Mask.  Associated  with  them  are  subordinate  beds  of  micasyte 
argillyte  and  clay-slate,  while  towards  the  west  they  graduate  into  quartzyte.  The 
clay-slate  and  argillyte  are  due  to  the  metamoiphism  of  ar^aceous  rocks,  wnile  in  thin 
locality  much  ra  tne  micasyte  was  originally  a  micaceous,  obliquely  laminated 
sandstone,  and  in  the  schist  it  is  quite  apparent  that  the  foliation  has  been  induced 
by  the  oblique  lamination.  The  "  Primary  Sandstonee"  are,  for  the  most  part,  mas- 
sive, compact,  and  hard,  generally  ver^  arinaceous,  but  sometimes  f  ehdtic ;  rarely 
are  they  gneissoid.  As  l£ey  graduate  into  quartzyte  a  fissUe  structure  is  developed 
parallel  to  the  stratification  planes;  they  are  generally  of  a  reddish  or  purplish 
colour. 

t  The  frilled  or  sharply  crumpled  structure  previously  mentioned,  in  some 
micasyte  and  talcytes,  is  the  only  exception  to  this  general  rule  that  I  have  detected. 
A  crumpled  lamination  occurs  in  some  unaltered  argillaceous  rocks,  to  which, 
in  another  place,  I  drew  attention  {On  Crumpled  Lamination  in  Shales,  Journal  Geol. 
Boc.,  Dublin,  1863) ;  but  that  has  its  representative  among  the  foliation.  This 
also  I  have  previously  pointed  out  {Notes  on  the  Foliation  of  the  gneiss  and 
Schist  of  TaT'Connaught^  Journal  Royal  Geol.  Soc.,  Dublin,  1866).  Moreover,  it  has 
not  an  aspect  analogous  to  this  structure  ;  furthermore,  it  is  rare,  while  this  is  not 
uncommon.  In  schistose-limestone,  schistose-dolomyte,  and  ophyte,  there  are  very 
complicated  foliations,  and  at  one  tune  I  was  inclined  to  suppose  they  must  be  due 
entirely  to  the  metamorphic  action.  This,  however,  I  find  not  to  be  the  case,  for,  on 
a  carend  examination  in  many  places  of  unaltered  limestone,  I  find  that,  as  a  general 
rule,  it  is  always  more  or  less  affected  by  all  sorts  of  irregular  structures  not 


EiNAHAN — On  Oranitk  and  other  Ingmite  Rocks.        109 

to  be  in  operation.  The  foliation  is  linear,  parallel,  and  perpendi- 
cular, or  nearly  so,  and  in  general  the  only  original  structure 
that  seems  to  affect  it,  seemingly,  is  the  strike  of  the  stratification.  As 
the  gneiss  became  more  and  more  granitoid,  and  perhaps  also  granitic, 
the  original  structure  gradually  became  obliterated,  and  the  foliation 
more  and  more  perpendicular.*  The  only  other  structure  that  in 
places  seems  to  resist  the  change  is  that  of  the  conglomeritic  gneiss. 
Usually  the  contained  blocks  in  the  latter,  as  the  rock  changes  from 
schist  to  gneiss,  become  elongated,  with  the  foliation  curling  more  or 
less  regularly  round  ithem  (fig.  F,  PL  9)  ;  and  as  the  rock  graduates 
into  gnmitoid-gneiss  a  linear  parallel  foliation  is  developed,  obliterating 
the  conglomeritic  foliation,  the  matrix  becoming  a  more  or  less  fine 
gneiss,  and  the  contained  blocks  coarse  gneiss,  the  margins  of  the 
latter,  as  shown  in  the  sketch  (fig.  D,  PI.  9),  being  rfCill  traceable ; 
but  eventually  one  kind  merges  so  completely  into  the  other  that,  ex- 
cept on  very  minute  examination,  no  difference  will  be  observed. 
This,  however,  is  not  always  the  case,  for,  in  some  places,  the  enclosed 
blocks  will  remain  distinct  in  both  composition  and  aspect ;  moreover, 
these  will  deflect  the  foliation  in  their  vicinity,  it  curling  round  them. 
Furthermore,  these  blocks,  although  generally  more  or  less  elongated, 
will  not  always  be  so  modified,  as  in  a  few  rare  instances  they  were 
remarked  to  be  more  or  less  angular,  the  latter  even  having  been 
observed  in  the  intrusive  oligoclasic-granite  (see  fig.  E,  PI.  9.)  In 
the  common  gneiss  of  the  gneist  series,  felspar  and  f elsite,  or  even  only 
f  elsite,  may  be  present  associated  with  the  mica  and  quartz ;  but  in 
the  granitoid-gneiss  all  the  constituent's  seem  to  be  developed  in 
regular  crystalline  particles,  no  felsite  matter  remaining,  it  all  having 
been  developed  into  quartz  and  felspar,  and  hereafter  the  microscopist 
may  prove  that  the  granitoid-gneiss  ought  not  to  be  kept  in  the  gneiss- 
series,  but  rather  included  among  the  granites,  and  called  Foliated  or 
OnstMoid-granite,  Nevertheless  the  granitoid-gneiss,  or  the  gneissoid- 
granite,  will  always  be  the  passage  rock  between  the  gneiss  and  the 
typical  granite.  The  accompanying  section  (fig.  R,  PI.  12)  shows 
the  passage  from  the  schist  into  typical  granite. 

Metamobphic  Derivate  Eocks. — Schist. — ^The  most  conspicuous 
it)cks  of  this  class  that  were  noted  in  the  area  to  which  this  essay 
refers  are : — ArgillytSy  or  Argillous-sehist,  Micasyte,  or  Mtea-sehist, 
Quartiffte,  or  Quarti'Sehist,  Samblendgte,  or  Amphibole-sehist,  Chlaritgte, 


generally  conspicnously  developed,  but  sufficient  to  induce  foliation,  and  similar 
m  their  sinnoeity  and  vagaries  to  those  found  in  the  schistose-limestone,  schistose- 
do^^yte,  and  ophyte. 

*  In  the  Geology  and  Zoology  of  Ahyssinia,  p.  169,  Blanford  calls  special  atten- 
tion to  the  regular  and  nearly  perpendicular  foliation  in  the^gneissic  rocks,  not  only 
of  that  country  but  also  of  western  India.  That  observer  suggests  that  it  is 
due  to  cleavage  in  the  original  rock.  This,  howeyer,  to  me  seems  improbable,  as 
one  and  the  same  cause  probably  affect  boUi  the  Irish  and  the  African  rooks,  and 
in  Ireland  it  was  not  deayage. 

It.  I.  A.  PKOC. — SBK.  II.,  yOL.  II.,  8CIBNCS.  Q 


110  Proceeduigs  of  t/ie  Royal  Irish  Academy. 

or  Rtpidolite'Schistf  Talcyte,  or  Taieschistf  FeUityte^  or  FehiU^schiHty 
SchUtoae'Limestone,  Schisto»e-dolamyte,  OphiolyUy  or  Serpentine^  and 
Steatyte, 

ArgiUyte, — Typical  axgillyte  is  an  argillous  rock,  in  which  the 
planes  of  lamination  are  more  or  less  glazed,  and  also  often  the  planes 
of  cleavage,  but  not  always,  as  some  slates  belonging  to  the  meta- 
morphic  series  have  a  more  or  less  earthy  cleavage  surface.  The  most 
common  of  the  varieties  in  this  area  seems  to  be  Chloritic-argiUyte, 
Clay-shtef  Steatitic-argillyte,  some  of  which  might  be  called  Ste<i- 
tityUy  or  Steatite-schist^  Homblendic-argillyte,  Arenaceotts-argillyte, 
Calcareoue-argillyte,  Dohmitie-argiHyte^  Ophiolitic-argillyte^  Pyritic- 
argillytej  and  Chiastolitic-argiUyte.  Structural  varieties  are  coarse, 
finCf  crtmpled,  spheroidal,  concretionary,  nodular,  eonglomeritic,  knotty, 
full  of  small  nodules  or  concretions,  giving  the  rock  a  knotty  aspect, 
irregular,  oblique,  and  rihaned,  the  latter  variety  being  rather  common.* 

Ificasyte, — This  rock  is  par  excellence  the  typical  schistose  rock  of 
the  country,  its  varieties  in  composition  being  nearly  innumerable,  and 
some  one  or  other  of  these  varieties  graduate  into  one  or  other  of 
every  kind  of  schist.  In  composition  the  principal  varieties  are 
argillous'tnicasyte,  two-micasyte,  quartzitic-micasyte,  hornblendic-mieasyte, 
ehloritie-micasyte,  talcose-micasyte,  gametiferous-micasyte,  felsitic' 
micasyte,  calcitic-micasyte,  dolomitic-micasyte,  ophiolitic-micasyte,  and 
pyritic-micasyte.  Any  of  these  varieties  may  graduate  in  one  of  the 
schists  hereafter  enumerated ;  moreover,  two  or  more  of  these  varieties 
may  be  combined,  forming  endless  sub-varieties. 

Micasyte  has  similar  structural  varieties  to  argillyte,  and  in  addi- 
tion to  these  the  peculiar  frilled  structure  previously  described  is 
common ;  also,  it  may  be  gneissoid,  through  which  it  graduates  into 
gneiss.  Two  subvarieties  of  quartzitic-micasyte  deserve  special 
mention  and  description.  One  is  fibrous-micasyte,  in  which  the  quartz 
is  arranged  in  thin  stalks  or  layers,  giving  the  rock  a  woody  aspect. 
In  some  the  stalks  are  long  and  irregular,  while  in  others  they  are  more 
or  less  ovate.  When  the  mliers  of  quartz  are  oval,  a  cross  section  of  the 
rock  has  a  marked  character  forming  a  more  or  less  regular  net- work. 
In  the  second  there  are  small,  thin,  round,  slightly  elongated  discoid 
pieces  of  quartz  scattered  through  the  rock,  sometimes  sparingly  but 
often  thicldy  together.  The  rock  when  weathered  has  the  appearance 
of  being  scattered  over  or  stuck  full  of  small  pieces  of  money  from  the 
size  of  a  sUver  penny  to  that  of  a  sixpence,  from  which  the  rock  might 
be  called  nummoid  or  money-schist.  The  fibrous  and  nummoid-schiiBts 
graduate  into  one  another. 

Quartzyte  or  Quartz-schist, — Quartz-schist  to  me  seems  to  bo 
given  a  prominence  to  which  it  is  not  entitled,  as  quartz-schist  am()p.g 

*  Other  varieties  may  occur,  but  in  this  and  all  other  liBts  only  the  rocks 
observed  are  mentioned.  Particular  descriptions  of  the  varieties  are  unnecessary, 
as  they  will  be  found  in  the  different  works  on  Petrology;  therefore,  in  this  essay, 
the  odHj  varieties  that  will  be  minutely  described  are  those  that  are  peculiar. 


KiNAHAN — On  Granitic  mid  other  Ingenite  Rocks,        111 

other  schist  is  not  even  analogous  to  grits  or  sandstones  in  a  gronp  of 
Bedimentaiy  rocks,  for  all  grits  and  sandstones  are  not  metamorphosed 
into  qaartz-schist,  many  changing  into  mica  or  other  schists.  In  this 
area  ttie  quartzyte  has  no  true  boundary,  as  both  in  depth  and  length 
it  graduates  into  other  kinds  of  sclust,  and  no  matter  how  cha- 
racteristic some  portions  of  a  series  may  be,  other  parts  will  be  so 
micaceous  or  felsitic,  &c.,  &c.,  that  except  for  their  associates  they 
would  never  be  classed  as  quartzyte.* 

The  quartzytes  generally  are  pale-greenish  or  white  in  colour,  but 
some  are  greyish,  blueish,  reddish,  or  blackish ;  compact,  hard,  but 
brittle ;  when  fractured,  often  have  a  saccharoid  aspect,  and  usually  have 
a  glimmering  vitreous  lustre.  Few  of  these  rocks  are  without  fldces  or 
plates  of  mica,  generally  white,  on  the  surface  of  the  stratification  or 
lamination  planes ;  some,  however,  are  more  or  less  massive,  and  in 
them  the  mica  is  not  very  conspicuous.  Many  of  the  quartzytes  are 
affected  by  irregular  joint  system,  on  which  account,  when  exposed  to 
atmospheric  influences,  they  break  up  readily  into  angular  shingle. 
Some  are  ribaned,  bands  of  different  colours  alternating ;  many  of  them 
seem  capable  of  being  split  into  flags,  which  is  rarely  practicable,  on 
which  account  they  are  locally  called  laek-avreay  i.  e.  tangled  flags. 

In  places  in  tiiis  area,  a  not  uncommon  variety  of  this  schist  is 
fehttie-quartzyU,  an  aggregate  of  quartz  and  f elsite.  This  often  occurs 
as  a  massive  or  thick-bedded  rock,  and  sometimes,  as  will  hereafter  be 
more  fully  stated,  it  may  possibly  not  be  a  metamorphosed  derivate- 
rock  (see  page  130).  Pelsitic-quartzyte  may  graduate  into  fehittfte, 
while  ordmary  quartzyte  generally  merges  into  quartzt/ttc-mieasf/te. 
It  has  been  pointed  out  that  usually  a  series  of  quartzytes  graduates 
into  one  or  other  of  the  different  groups  of  schist ;  there  is,  however, 
one  remarkable  exception,  as  lenticular  masses  and  subordinate  beds  of 
homhlendyte  are  not  uncommon  among  the  quartzvtes  of  Yar-Con- 
naught,  and  between  these  two  kinds  of  rock  there  is  nearly  always  a 
hard  abrupt  boundary.  These  subordinate  beds  of  homblendyte  will 
again  be  mentioned. 

Hwrnbhndyte  or  Ampkihole-schist. — Homblendic-micasyte  graduates 
into  homblend3?te,  while  the  latter  often  merges  into  chloritt/te 
or  talcyts.  The  most  interesting  of  all  the  schistose  rocks  in  Yar- 
Connaught  are  the  homblendytes,  as  they  for  the  most  part  must 
originally  have  been  tuffs  or  tu^ose  rocks,  as  they  are  intimately  asso- 

*  There  are  some  rocks  called  quartzyte  (the  Quartz-rock  of  Jukes^  such  as  those 
at  Bray  Head,  Co.  Wicklow ;  to  these,  however,  I  do  not  refer,  as  I  belieye  that  they 
and  ordinary  quartz-schist  belong  to  quite  different  classes  of  rock.  From  my  above 
remark  I  do  not  mean  to  say  that  in  mapping  a  country  the  quartzyte  ought  to  be 
ignored ;  on  the  contrary,  I  always  advocate  that  any  remarkable  beds,  no  matter 
how  insignificant,  ought  to  be  traced  out  if  the  geology  of  the  area  is  to  be  properly 
ascertained.  But  I  do  object  to  hypothetical  boundaries  being  laid  down ;  and  if 
quartzyte  is  to  be  given  a  hard  boundary  and  a  separate  colour  on  geological  maps, 
so  ought  micasyte,  homblendyte,  felsityte,  &c.,  and  every  bed  ^  sandstones  or 
grits  among  sedimentary  rocks ;  the  absimiity  of  which  must  strike  everyone. 


112  Proceedings  of  (he  Royal  Itnsh  Academy. 

ciated  with  bedded  and  intrusiye  masBes  of  homhknde-roek.  Of  such 
rocks  Jukes  Bays :  '*  It  is  very  possible  that  many  homblende-schifits, 
actinolite-schistsy  &c.,  are  metamorphosed  tnffs."*  Of  tuffs  and  tuffose 
rocks  Forbes  thus  writes — "  Subaerial  or  subaqueous  outbursts  may 
force  into  the  sea  irruptive  rocks,  which,  being  at  once  broken  up  into 
a  state  of  division,  more  or  less  fine  in  proportion  to  the  greater  or 
lesser  cooling  power  of  the  water-mass  in  immediate  contact,  may  be 
spread  out  into  beds  by  the  action  of  the  waves.  The  texture  of  these 
rocks  may  vary  from  that  of  the  coarsest  breccia  down  to  the  finest 
mud,  and,  as  is  usually  the  case,  such  deposits  may  present  themselves 
as  alternating  beds  of  coarse  and  fine  character.  Upon  the  consolida- 
tion of  such  formations,  rocks  are  formed  identical  in  chemical  and 
mineralogical  composition  with  the  original  irruptive  rock  from  which 
they  were  derived,  and  which,  particularly  when  close-ghdned,  often 
present  an  external  appearance  so  like  the  original  rocks  as  to  be  fre- 
quently undistinguishable  from  them  by  the  naked  eye."f  Scrope  and 
the  other  historians  of  the  volcanic  regions  mention  the  accumulations 
of  agglomerates  and  other  tuffose  rocks  often  associated  with  volcanic- 
rocks,  while  in  various  places  in  Ireland,  such  as  the  plain  of  Limerick 
and  the  vicinity  of  Valencia  Harbour,  Kerry,  there  are  similar  accumu- 
lations associated  with  plutonic  rocks ;  therefore,  it  does  not  appear  at 
all  improbable  that  these  ancient  exotic  rocks  of  Yar-Connaught  should 
also  have  had  associated  tulfs  and  other  such  mechanical  accompani- 
ments. 

The  homblendytcs  of  Yar-Connaught  range  from  a  fine,  almost 
compact,  rock  to  a  massive  conglomeritic  rock  containing  enclosed 
masses  or  blocks  often  yards  in  width. 

The  conglomeritic-homblendyte  is  always  more  or  less  associated 
with  protrusions  or  beds  of  hornblende-rock.  In  places  they  graduate 
into  one  another  through  a  nodular  or  spheroidal  variety  of  the  latter, 
while  the  conglomeritic-rocks,  on  the  other  hand,  gradually  loose  all  their 
blocks  and  merge  into  ordinary  schist.  In  others,  the  hornblende-rocks 
and  the  conglomeritic  are  intermingled  together  irregularly,  and  the 
mass  formed  of  both  combined,  will  be  surrounded  by  the  regular 
stratified  rocks  of  the  country.  This  would  seem  to  be  additional 
proof  if  any  more  is  wanted,  of  these  rocks  originally  being  tuff  and 
agglomerates;  for  such  a  mass  as  that  represented  in  figs.  Q,  Fl.  11, 
and  R,  Fl.  12,  may  well  be  considered  the  remains  of  aa  accumulation 
formed  around  a  subaqueous  plutonic  vent. 

In  the  immediate  vicinity  of  a  mass  or  tract  of  hornblende-rock  the 
enclosed  blocks  in  the  conglomerate  will  be,  for  the  most  part,  some 
one  or  other  variety  of  igneous  rock,  some  having  an  aspect  like 
scoria  or  pomice.  Farther  away  they  will  be  mixed  with  blocks  of  one 
or  more  other  kinds  of  rock,  and  eventually  all  the  blocks  will  gradually 
disappear  and  the  rock  graduate  into  an  ordinary  schist.     In  one  locality 

*  Manual  of  Geology  by  J.  Beete  Jukes,  M.  A.,  F.  R.  S.,  second  edition  p.  82. 
t  The  Microscope  in  Geology^  p.  10. 


KiXAHAN — On  Granitic  and  other  Ingenite  Rocks,        113 

blocks  of  f elstone  were  observed  in  a  conglomeritic  schist ;  these  were 
not  only  remarkable  but  highly  instnictiYe,  for  they  not  only  proved 
that  felstones  must  have  existed  prior  to  the  formation  of  this  sedimen- 
tary rock,  bnt  also  that  some  felstones  are  less  susceptible  of  change  than 
whlnstones,  for  while  the  matrix  was  a  well  marked  schist,  and  in  the 
associated  blocks,  mostly  hornblende-rock,  there  was  more  or  less  folia- 
tion, these  were  verysmiilar  to  ordinary  f  elstone,  the  only  alteration 
that  was  evident  being  an  almost  microscopic  foliation,  obscurely 
visible  to  the  naked  eye,  on  weathered  surfaces. 

The  f oHation  in  the  conglomeritic-schists  is  irregular.  That  in  the 
enclosed  blocks  may  run  in  various  directions,  while  that  of  the  matrix 
has  a  greater  or  less  tendencv  to  curl  round  the  blocks,  but  in  some 
cases  it  is  very  irregular  (fig.  F,  PL  9). 

The  fine  homblendyte  is  often  more  or  less  associated  with 
hornblende-rock.  Sometimes  the  latter  rock  at  the  margin  graduates 
into  it,  when  it  is  impossible,  except  pieces  of  the  ro(^s  have  been 
subjected  to  microscopic  examination,  to  say  where  one  rock  ends  and 
the  other  begins ;  while  at  other  times  it  occurs  as  lenticular  patches 
or  layers  enclosed  in  the  mass,  or  as  thin  partings.  In  such  cases  it  is 
probable  they  were  formed  from  the  disintegrated  portions  of  the  ori- 
ginal igneous  rock  due  to  its  contact  with  water,  the  enclosed  layers 
and  patches  marking  the  limits  of  different  flows  or  beds.*  Pine  hom- 
blendyte may  also  occur  as  independent  beds  when  it  often  grar 
duates  into  chlorityte,  talcyte,  stcatityte,  or  homblendic-micasyte, 
but  it  is  most  remarkable  when  it  appears  associated  with  quartzyte, 
for,  as  previously  remarked,  in  such  places  it  rarely  graduates  mto 
that  schist,  such  masses  apparently  being  due  to  showers  of  tuif 
falling  on  water  and  settling  down  in  one  place,  forming  a  distinct, 
small,  but  independent,  patch  of  rock.  All  the  fine  homblendytes  are 
more  or  less  epidotic  or  they  may.  change  into  a  rock  that  might  be 
called  epidoticyte. 

The  weathering  of  these  fine  schists  and  also  many  other  varieties 
of  schist  that  are  more  or  less  basic  should  be  noted,  for  in  them  the 
old  joint  lines  seem  to  have  been  cemented  or  sealed,  while  layers  of 
rock  in  juxtaposition  to  the  joint  lines  have  been  hardened,  hereby 
causing  on  weathered  surfaces  more  or  less  angular  figures  (figs.  G,  H, 
PI.  9,  and  P,  PI.  10).  In  the  more  siliceous  rocks  the  old  lines  are 
not  so  often  cemented  or  sealed,  but  it  is  not  uncommon  even  in 
granites  to  find,  adjoining  to  the  joint  lines,  layers  indurated,  appa- 
rently siUcified  (fig.  H,  PI.  9). 

Chlorittfte,  Talcyte, — ^These  rocks  seem  to  be  very  much  allied, 
as  one  rarely  occurs  without  the  other.  Some  were  observed  to  be 
tourmalinic,  others  gametiferous.  They  graduate  into  varieties  of 
micasyte  and  into  homblendyte. 

Fehityte, — ^This  schist  has,  besides  others,  two  marked  varieties, 

*  Tuifoeie  layen  between  flows  or  beds  of  plutonic  rooks  are  found  in  Cork, 
Keny,  limerick,  and  other  places. 


114  Pfoceedings  of  the  Royal  Irish  Academy. 

namely,  the  fine  compact  and  the  scaly  friahle.  The  fine  rock  has  an 
aspect  yery  similar  to  quartzyte,  hut  distingiiishahle  from  that  schist 
hy  its  always  weathering  with  a  white  cnist  similar  to  felstone.  The 
scaly  or  friable  felsityte  seems  for  the  most  part  to  he  an  aggregate 
of  minute  felspathic  flakes  or  scales ;  nevertheless,  it  is  very  tough  and 
hard  to  break  across,  but  along  the  grain  can  be  split  with  greater  or 
less  facility ;  across  the  grain  it  breaks  with  a  Jbackly  fracture.  It  is 
always  more  or  less  steatitic.  This  variety  of  felsityte  sometimes 
occurs  as  a  stratified  rock,  but  in  the  country  north  of  Killary 
Harbour  it  undoubtedly  is  in  places  part  of  an  intrusive  mass,  being 
the  tuffoid  portion  of  the  hereafter  mentioned  felstone  protrusions, 
which  rock  having  been  metamorphosed  is  changed  into  these  schists. 
It  may  be  here  suggested  that  all  the  felsitytes  and  perhaps  also 
the  fclsitic-quartzytes  are  probably  metamorphosed  felsitic  tuffs  and 
tuffose  rocks.  These  rocks,  however,  will  hereafter  be  more  fully 
considered. 

Subordinate  schists  which  claim  separate  descriptions  are  pyrrho- 
tityU  or  pyrrhotite-sehist  and  rhatizityte  or  maynMian-sohist  on  account 
of  their  remarkable  composition,  the  former  also  having  been  worked 
for  the  minerals  it  contains. 

Pyrrhotityte,  when  typical,  is  a  crystalline  aggregate  of  quartz, 
pyrrhotite,  pyrite,  and  chalcopyrite,  with  a  little  mica.  As  the  mica 
increases  in  quantity  the  sulphides  decrease  until  eventually  the  rock 
passes  into  mica-schist.  In  some  varieties  the  mineralogical  metals 
predominate  to  the  nearly  total  exclusion  of  all  others ;  however,  it  is 
very  variable  in  its  composition,  having  many  accessories,  and  changing 
rapidly  from  a  highly  metalliferous  to  a  non-metalliferous  rock.* 

Rhatizyte  or  MagneBtan-nchist. — This  was  only  observed  in  one 
locality  (Cannaver  Island,  Lough  Corrib).  Of  specimens  of  the  rock 
Mr.  Forbes  says — **  Very  identical  with  one  described  by  me  in  Nor- 
way."! 

Schistose-linustoney  SchistoBe-dolomyUy  OphiolytejandSteatyU. — ^These 
rocks,  although  different  in  aspect  and  composition  to  all  other  schistose- 
rocks,  must  be  classed  among  them,  as  they  graduate  into  some  one  or 


♦  Here  it  may  be  mentioned  that  in  connexion  with  these  schists  there  are 
metalliferous  lodes  evidently  older  than  the  associated  granite- veins,  and  apparently 
of  metamorphic  origin.  These  consist  of  a  crystalline  aggregate  of  pyrrhotite, 
P3^te,  chalcop3rrite,  quartz,  mica,  orthoclase,  and  oligoclase,  with  marcasite,  amphi* 
bole,  &c.,  as  accessories.  Adjoining  such  lodes  more  recent  lodes  usually  occur. 
There  are  also  veins  of  garnet-rock  which  seem  to  be  connected  with  the  metalli- 
ferous stratA,  as  they  were  not  noted  in  any  other  parts  of  the  country.  This  vein- 
rock  is  a  more  or  less  crystalline  mass  of  brown  garnet ;  when  very  crystalline  it 
usually  contains  crystals  of  pyrrhotite,  pvrite,  chalcopyrite,  quartz,  oligoclase,  &c., 
with  tne  interstices  filled  with  epidote  and  ribaned  pearl-spar.  Some  fine  crystals  of 
the  epidote  have  been  observed.  The  garnet  crystals  vary  in  size,  some  being  over 
an  inch  in  diameter. 

t  For  the  description  of  the  Norway  rock,  see  Quar.  Jour.  Geol.  Soc.,  Lond., 
August,  1868. 


KiNAHAN — On  Granitic  and  other  Ingenite  Bocks,        115 

other  of  the  previously  described  schists,  and  eyentually  when  more 
highly  metamorphosed  they  appear  to  lose  their  individual  character. 

All  the  limestones  and  dolomyte*  to  be  described  are  more  or  less 
schistose,  yet  in  many,  the  calcareous  or  dolomitic  ingredients  seem  to 
predominate  to  the  nearly  total  exclusion  of  all  others.  This,  however, 
may  be  more  apparent  than  real,  and  in  such  rocks  the  different  foreign 
substances  may  be  amalgamated  in  the  mass ;  for  the  purest  of  these 
limestones,  as  compared  with  the  carboniferous  limestones,  give  in  the 
proportion  of  1*5  to  2*5  or  3  of  lime,  equal  quantities  of  both  being 
burnt. 

The  limestone  may  be  white  and  of  a  saccharoid  aspect.  This  is 
sometimes  a  handsome  stone,  but  in  many  cases  it  is  impregnated  with 
pyrite  or  marcasite,  and  consequently,  when  exposed  to  atmospheric 
influence,  it  becomes  discoloured.  These  white  varieties  occur  in 
various  places,  but  the  common  colour  of  the  schistose-limestone  are 
shades  of  blue  and  grey.  The  magnesian-limestone  is  usually  white 
or  pale  dove-colour;  the  white  rock  is  sometimes" dolomyte,  but  not 
always,  as  many  are  calcitio-dolomytes.  The  pale  dove-colour  rocks 
seem  generally  to  be  a  mixture  of  calcityte  and  dolomyte.  Some- 
times the  calcityte  will  occur  in  streaks,  layers,  specks,  or  patches  in 
a  dolomitic  mass,  or  the  dolomyte  will  similarly  occur  in  relation  to 
calcityte.  One  variety  of  the  dolomyte  is  a  milk-white,  compact, 
homogeneous  flne-stone,  breaks  with  a  conchoidal  fracture,  has  exter- 
nally the  aspect  of  alabaster,  takes  a  fine  polish,  but  is  haxd  and  some- 
what difficult  to  cut. 

The  pale  dove-coloured  dolomyte  and  the  calcitic-dolomyte  appear 
to  be  the  parent  rocks  of  the  ophiolytes  and  ophicalcytes,  commonly 
known  as  '^  Connemara  serpentine  or  marble  ;"  both  of  these  rocks  in 
places  occur  in  mass.  At  the  surface  of  the  ground  the  purest  rock 
seems  always  to  occur ;  some,  apparently,  answering  Dana's  description 
of  previous  serpentine.  This  rock  in  depth  seems  to  graduate  into  dolo-* 
myte  and  calcitic-dolomyte.  Similarly  at  the  surface  ophicalcyte  may 
occur,  while  in  depth  it  seems  to  merge  into  calcitic-dolomyte.  The 
colours  of  the  serpentines  are  various,  dark  green,  nearly  black,  pale 
green,  greenish  yellow,  streaked,  ribaned,  variegated,  maculated,  and 
variolitic  varieties  having  been  observed,  the  combinations  including 
different  shades  of  green,  yellow,  white,  grey,  and  blue,  with,  on  rare 
occasions,  red,  separately  or  combined.! 

Associated  with  the  ophiolytes  and  ophicalcytes  are  ophitio  and 
steatitic-schists,  and  in  some  places  steatyte  ;  these  sometimes  are  of  con- 
siderable thickness.  There  are  also  green  unctuous  schists  that  may 
possibly  be  tmaragdityte  or  MMragdite-MhiatX 

*  Dolomyte  is  the  rock,  dolomite  the  mineral. 

t  Ophytee  also  are  found  in  Yar-Coiinaught.  They,  however,  are  peeudomorphose 
igneouA  rocks  and  >rill  be  described  with  them. 

X  These  latter  rocks  seem  to  be  described  by  Cotta  as  a  variety  ol  eklogytey  but 
typical  eklogyte  seems  to  be  a  pseudomorph  ingenite  rock. 


1 16  Proctfding^  of  the  Royal  Irish  Academy. 

Gneiu. — Gneiss,  as  prerioaalj  stated,  ranges  from  schistose  to 
granitoid  in  stmctnre.  Tliey  may  he  fine,  piaty,  rihamedj  compaeiy  coarse, 
fihnms,  yrtmiUni,  perphyritie,  n^mlar,  or  conylomentie.  The  four  first 
Tarieties  usually  are  characteristic  of  the  sctust-series,  in  which  they 
occur  as  sabordinate  rocks.  In  the  ribaned  all  the  constituents  are  of 
small  sizes  and  form  thin  even  layers ;  the  fibrous  has  a  structure  some- 
what similar  to  fibrous  schist ;  the  granitoid  and  porphyritic  varieties 
seem  generally  to  occur  together,  while  most  of  the  nodular  and  con- 
glomeritic  gneiss  seems  to  be  metamorphosed  agglomerates. 

In  composition,  gneiss  may  vary  from  highly  siliceous  to  basic. 
Barely  is  it  typical,  that  is,  being  composed  only  of  plates  or  layera 
of  quartz,  felspar,  and  mica,  as  various  other  minerals  will  also  be  pre- 
sent, sometimes  only  as  accessories,  but  generaUy  as  essentials  in  addi- 
tion to  or  in  part  replacing  the  typical  constituents.  On  this  account 
the  varieties  and  sub-varieties  are  numerous,  the  following  being  the 
most  remarkable — quarUiiie,  fehitie,  mieaeeous,  kornblendic,  ehlorittc, 
and  pyritie,  the  rock  being  named  after  the  mineral  that  is  more 
developed  or  more  conspicuous  than  the  others,  giving  a  character  to 
the  mass. 

Hornblende-rock, — ^Tlus  rock  is  found  as  a  bedded  rock  also  in  dykes 
and  intrusive  masses.  Associated  with  it  are  schist  and  gneiss,  the 
rocks  from  which  it  was  formed  evidently  having  been  intruded  con- 
temporaneously with  the  deposition  of  the  original  sedimentary  rocks. 
Also  associated  with  these  rocks  are  granites  tibat  are  supposed  to  be 
metamorphosed  f elstones ;  consequently,  it  would  seem  that  some  of 
these  granite  veins  are  older  than  some  of  the  hornblende  rock.  This, 
however,  is  more  apparent  than  real.  Both  kinds  of  iock  (whinstone 
and  felstone)  seem  to  have  been  ejected  at  different  intervals  during 
the  accumulation  of  the  sedimentary  rocks,  but  all  were  metamorphosed 
at  the  same  time,  the  basic  igneous  rocks  being  changed  into  horn- 
blende-rock, and  the  highly  sUiceous  rocks  into  granitic  or  granitoid- 
rocks,  on  which  account  it  is  evident  such  granites  cannot  be  older 
than  the  hornblende-rock,  while  the  rocks  from  which  the  latter  were 
formed  must  have  been  intruded  prior  to  the  granite  that  was  intruded 
during  or  subsequent  to  the  metamorphism  of  all  the  rocks. 

Hornblende-rock  varies  much  both  in  structure  and  composition, 
apparently  according  to  the  nature  of  the  original  rocks ;  stUl,  how- 
ever, all  the  varieties  may  conveniently  be  grouped  under  this  old 
name  of  Macculloch.* 

Large  protrusions  of  plutonic  rocks  in  other  localities,  especially 
if  in  part  bedded  masses,  vary  much  in  composition,  part  being 
eurytes  (basic  felstones),  and  part  whinstones,  both  often  occurring 
associated  together.  Such  would  also  seemingly  have  been  the  original 
condition  of  the  igneous  rocks  of  Yar-Connaught,  in  part  occurring 
as  outbursts  and  dykes,  in  part  as  bedded  masses,   and  the  latter 

•  See  Handy  Book  erf  Bock  Namee,  by  the  writer  (Haidwicke,  1873),  p.  61, 
et  leq. 


KiNAHA^ — On  Granitic  and  other  Ingenite  Rocks,        117 

associated  with  tuffs  and  agglomerates,  while  in  composition  they 
varied  from  felstones  (probably  as  in  the  Co.  Limerick  and  elsewhere 
more  or  less  basic)  to  whinstones,  and  the  different  Tarieties  of  the 
original  rocks  are  now  recorded  by  the  variations  in  the  metamorphic 
rocks.  The  most  common  rock  of  this  class  in  Yar-Connaught  appears 
to  be  an  aggregate  of  crystals  of  amphibole,  bluish  or  greenish  felspar, 
pyrite  or  marcasite,  and  a  little  ripidolite,  mica,  or  such  like  as  acces- 
sories. It  may  be  from  finely  to  coarsely  crystalline.  Some  are  so 
fine  and  compact  that  they  might  be  called  homhlende-aphanyte. 
Others  are  an  aggregate  of  crystals  of  amphibole,  often  apparently  to 
the  nearly  total  exclusion  of  all  other  minerals.  When  very  coarse 
the  crystals  vary  from  two  to  four  or  five  inches  in  length.  These 
rocks  seem  to  be  the  typical  hornblende-rock  of  Macculloch,  Haughton^ 
Dana  and  others.  A  variety  not  unconmion  has  well  developed  crys- 
tals of  felspar,  not  orthoclase  {dioryte)  ;*  while  in  another  variety 
the  felspar  is  orthoclase  {jsyenyte),  quartz  also  often  being  present,  not 
necessary  as  an  essential  but  rather  as  an  accessory  ingredient.  One 
sub-variety  of  the  syenyte  is  remarkable,  the  orthoclase  being  devel- 
oped to  the  nearly  total  exclusion  of  the  other  minerals,  the  rock  being 
a  whitish  or  fiesh-coloured  mass  through  which  crystals  of  amphibole 
are  scattered;  this  sub-variety  {feUo-syenyte)  was  only  observed  in 
very  subordinate  quantities.  Some  hornblende-rock  has  orthoclase  in 
addition  to  the  other  felspars ;  in  a  variety,  Messrs.  Eorbes  and  King 
(India)  called  hyperyte,  hyperstene  replaces  the  amphibole.  As  some 
of  these  hornblende-rocks  are  metamorphosed  diabase  [pyrovene  (dial- 
lage)  +  felspar  (not  orthoclase)  +  ripidolite],  portion  of  the  diallage  may 
remain  unaltered,  or  portions  may  be  replaced  by  hyperstene  or  an 
allied  mineral,  thereby  forming  various  complicated  sub-varieties  of  the 
rock. 

In  some  varieties  of  honfblende-rock  mica  occurs  as  an  accessory, 
but  in  others  as  an  essential  {mii!0'homhlende-rock).  Commonly  it  is 
a  small  black  or  blackish  brown  mica  occurring  more  or  less  abundantly, 
but  besides  black,  white,  pale  sea-green,  bronze,  and  reddish  violet 
have  been  observed.!  Some  of  these  rocks  seem  to  answer  the  descrip- 
tion for  kersantyte  of  Delesse.  The  white  and  the  pale  sea-green  mica 
generally  occurs  in  large  flakes,  while  the  bronze  and  reddish  violet 


*  f6r.  diorasy  a  clear  distinction).  I  wonld  suggest  that  it  was  to  rocks  of  this 
class  tne  name  was  originally  given,  as  in  them  the  minerals  are  always  quite  dis- 
tinct. 

t  Mico-homblende-TOck  is  called  by  some  **  micatrap.*'  This  classification 
appears  to  be  very  vague,  and  evidently  the  group  is  not  a  petrological  division. 
Under  this  name  they  include  minnette  or  micaceous-felstone  and  micaceous-elvanyte, 
kersanton  or  micaceous-dioryte  keraantyte,  or  micaceous-diabase,  micaceous- 
melaphyre,  micaceoiis-doleryte,  &c.,  &c.,  rocks  belonging  to  quite  different  groups. 
Moreover,  part  of  a  dvke  in  accordance  with  this  clasnfication  might  be  a  mica-trop, 
while  the  rest  of  it  belonged  to  a  different  class,  or,  what  is  not  uncommon,  the 
margins  of  the  dyke  might  be  mica-trap,  while  the  centre  was  dolerytc  or  dioryte  or 
feUtone  or  eurj^te  or  elvanyte. 

R.  I.  A.  PROC,  KEK.  II.,  VOL.  II.,  8CIENCK.  R 


118  Proceedings  of  the  Rot/al  Irish  Academy. 

usually  is  developed  in  small  pockets,  distributed  regularly  and  abun- 
dantly through  the  mass.  As  the  mica  decomposes  more  readily  than 
the  other  constituents,  weathered  surfaces  of  these  mico-homblende- 
rocks  have  peculiar  appearances.  K  the  mica  occurs  in  pockets  or 
nests,  the  rock  surface  becomes  coarsely  pitted  (see  fig.  I.  PI.  9),  while  if 
it  is  developed  in  large  flakes,  the  rock  when  wea^ered  presents  sur- 
faces on  which  are  rude  characters  having  a  more  or  less  angular  arrange* 
ment,  as  represented  in  the  accompanying  sketch  map  (fig.  J,  PI.  9) 
of  a  portion  of  a  rock  containing  large  flakes  of  silvery  white  mica. 
Such  varieties  of  the  hornblende-rock  are  easily  recognised  on  account 
of  the  pecidiar  weatherings. 

The  varieties  of  hornblende-rock  in  places  graduate  into  a  granite 
similar  to  the  rock  called  Oah^ay-type  granite  in  the  memoirs  of  the 
Irish  branch  of  the  Geological  Survey.  Its  description  will  be  given 
hereafter. 

Actinolite  or  tremolite,  wholly  or  in  part,  may  replace  the  other 
amphiboles,  and  the  rock  may  consist  of  numerous  hyaline  acicular 
ciystals  mixed  with  a  felspathic  paste,  or  numerous  nests  of  such  crys- 
ttus  may  occur  in  an  amphibolic-fclspathic  matrix. 

The  actinolitic  and  tremolitic-homblende-rocks  are  more  or  less 
ophitic,  or  graduate  into  ophytef  steatyte,  and  such  like  rocks,  the  gra- 
dation being  very  apparent  among  tiie  rocks  of  the  previously  men- 
tioned Cannaver  Island. 

The  ophyte  of  this  area,  due  to  the  decomposition  of  igneous 
rock,  is  usuadly  of  a  dark  leek-green,  approaching  black,  colour,  never- 
theless a  few  subordinate  patches  of  a  light  green  were  noted ;  always 
it  is  more  or  less  associated  with  hornblende-rock  in  places  having  sub- 
ordinate beds  or  layers  interstratified ;  the  passage-rock  between  the 
two  may  be  called  ophitic  kornhlende-rock  or  amphiholic-ophyte,  according 
to  the  mineral  predominating.  In  some  of  these  passage-rocks  crystals 
of  amphibole  occur  in  an  ophitic  matrix,  or  blotches  or  maculas  of 
ophyte  may  be  developed  in  an  amphibolic  base,  or  ophitic  and  amphi- 
bolic particles  may  be  more  or  less  intimately  mixed  together.  In  some 
it  is  evident  that  a  homblendic  mineral  has  produced  the  ophyte,  while 
in  other  rocks  it  seems  to  be  a  pseudomorphism  of  a  felspar.  In  some 
of  these  rocks,  flakes  of  a  mineral,  in  aspect  like  diallage,  were 
observed. 

Massive  ophyte  is  divided  by  Dana  into  precious  and  common.  The 
first  "is  of  a  rich  oil-green  colour,  of  pale  or  dark  shades,  and  translu- 
cent even  when  in  thick  pieces."  The  second  "  is  of  dark  shades  of 
colour,  and  subtranslucent.  The  former  has  a  hardness  of  2*5 — 3  ;  the 
latter  often  of  4,  or  beyond,  owing  to  impurities."  In  west  Galway, 
among  the  rocks  of  intrusive  origin,  no  precious  or  noble  serpentine  was 
observed.    • 

A  rock  allied  to  those  just  described,  and  evidently  a  pseudomorph 
of  hornblende-rock,  has  a  bright  green  colour,  and  an  unctions,  com- 
pact, homogeneous,  tough  matrix,  in  which  are  imbedded  more  or  less 
irregular  crystals  or  crystalline  patches  of  garnet,  flakes  of  mica,  with 


KiNAUAN — On  Granitic  and  other  Ingenite  Mocks.        119 

crystals  of  cyanite ;  pyrite  may  also  be  detected  in  it.  A  specimen  of 
this  rock  was  deterxnined  by  Mr.  D.  Forbes  to  be  eklogyte,  while  Mon. 
A.  Gage  says  it  does  not  present  the  physical  characteristics  of  that 
well-known  rock,  but  properly  belongs  to  the  serpentine  series. 

Steatyte  occnrs  as  subordinate  quantities  associated  with  the  ophyte, 
usually  at  the  margin  of  masses,  or  in  lenticular  patches  or  irregular 
Teins;  however,  in  other  places  it  appears  in  mass.  When  freshly 
broken  it  is  of  a  pale  greenish  grey  colour,  but  becomes  a  pale  bluish 
grey  shortly  after  being  exposed  to  the  air ;  and  subsequently  decom- 
poses into  a  rusty  white  or  dirty  cream-coloured  substance.  It  is  more 
or  less  fissile,  very  unctions,  tough,  splits  along  the  grain,  but  across  it 
breaks  with  a  hackly  fracture. 

Steatyte  in  mass  in  places  graduates  into  felsityte  or  homblend- 
yte.  In  the  country  north  of  Killary  bay,  the  previously  men- 
tioned tuffoid  portions  of  the  protrusions  of  felstone  (p.  114)  graduate 
through  felsityte,  and  steatitic-felsityte  into  steatyte,  while  on  Bofin 
and  Sharke  islands  the  steatyte  is  associated  with  homblendyte  and 
talcyte,  and  the  mass  formed  of  these  rocks  combined  appears  to  come 
up  as  a  protrusion  among  the  metamorphosed  sedimenta^  rocks,  while 
in  the  protrusion  are  peculiar  irregular  pipes,  and  bomb-shaped  masses 
of  compact  hornblende  rock  {Hornblende-aphony te),    (See  fig.  £,  PL  10.) 

From  these  circumstances  I  am  led  to  suggest  that  the  steatyte  was 
originally  fine  tuff,  either  basic  or  felspathic,  in  which  were  pipes  and 
irregular  veins  of  igneous  rocks,  the  remains  of  an  accumulation 
formed  in  the  vicinity  of  a  subaqueous  plutonic  outburst,  similar 
to  that  previously  mentioned  when  describing  the  homblendytcs 
(p.  116).  These  masses  would  seem  not  to  have  been  intruded  up 
among  the  sedimentary  rocks,  but  rather  to  have  been  protrusions,  that 
subsequently  were  in  part  denuded  away,  while  round  them  the 
sedimentary  rocks  were  being  deposited,  till  eventually  the  latter 
enveloped  them.* 


*  In  fayonr  of  thiB  sngfgestion  it  should  be  stated  that,  in  the  places  where  horn- 
blende rock,  in  combination  with  homblendjte  and  conglomeritic-schist,  form 
masses  that  axe  protrusions  in  the  associated  gneiss  and  schists,  the  latter  rocks 
seem  to  be  allied  to  them,  having  originally  been  formed  of  somewhat  similar 
materials.  In  the  neighbonrhood  of  the  protrusions  of  steatyte  on  Bofin  and 
Sharke,  the  schists  are,  more  or  less,  homblendic  andtaloose,  and  in  the  country  north 
of  Killary  harbour  the  schists  in  the  neighbourhood  of  the  felspathic  mass  are, 
more  or  less,  felspathic,  many  of  them  being  felsityte.  This  should  be  expected  if 
the  above  is  correct ;  as  part  of  the  acciunulation  of  tuff  would  remain  as  an  irregu- 
lar mass,  while  the  portions  destroyed  by  denudation  should  be  deposited  around 
the  residue;  and,  although  not  exactly  similar,  yet,  in  a  fretX  measure,  par- 
taking of  its  nature.  To  account  for  the  rooks  north  of  Killary  harbour,  we 
might  suppose  a  protrusion  of  felstone  somewhat  similar  to  one  of  these  in 
Anvergne,  except  that,  instead  of  being  snbacial,  it  was  subaqueous ;  the  outside 
poition  of  such  a  mass  would  be,  more  or  less,  disintegrated,  and  pulverised, 
during  the  cooling  process,  by  the  water-mass  in  contact,  and  thereby  produce 
materials  that,  when  deposited  around,  would  form  rocks  very  similar  in  com- 
position and  aspect. 


120  Proceedings  of  the  Soyal  Irish  Academy. 

The  homblende-rock  often  merges  into  a  nodular  variety,  or, 
88  preyiously  stated,  it  may  graduate  into  homblendyte.  (See  figs. 
L,  M,  and  N,  PI.  10). 

Often  between  it  and  the  homblendyte  there  is  no  rigid  boundary, 
their  mineral  composition  apparently  being  identical,  on  which  account 
the  derivate  rock  would  seem  to  have  been  formed  from  fine  particles 
abraded  ofF  the  mass,  or  from  the  outer  portion  having  been  pul- 
verised, and  disintegrated  from  its  contact  with  the  water  into  which 
the  rocks  were  protruded,  while  subsequently  they  were  re-arranged 
or  stratified.* 

Nodular^  or  spheroidal  homhlende-rock,  is  made  up  of  blocks,  or 
irregular  spheroids,  from  the  size  of  a  man's  fist  to  five  or  six  feet  in 
diameter,  irregularly  heaped  together,  the  interstices  being  filled  with 
a  schistose  substance,  which  is  sometimes  more  or  less  *  curved  round 
the  blocks,  or  with  a  felsitic-schistose  rock,  or  even  with  quartzitic 
stuff,  or  a  mixture  of  their  substances.  A  very  peculiar  variety  of 
this  rock,  only  observed  in  one  or  two  places,  had  a  felsitic-schistose 
matrix,  very  like  felspathic-dioryte,  except  that  it  is  foliated,  in 
which  the  blocks  of  homblende-rock  were  enveloped.  This  rock  merged 
into  the  homblende-rock,  but  not  into  the  associated  gneiss  and 
schist. 

Usually,  as  previously  stated,  the  nodular-homblende-rock  merges 
into  conglomeritic  schists  or  gneiss  {metamorphosed  agglomerate)  so  gra- 
dually, that  no  boundary  can  be  drawn  between  the  two  kinds  of  rock ; 
for  which  reason  it  would  appear  that  this  variety  is  not  originally  a 
normal  igneous  rock,  but  rather  represents  the  broken  up  portions  of 
the  flows,  rounded  by  abrasions  against  one  another,  or  by  weathering, 
while  the  interstices  were  filled  by  the  abraded  and  disintegrated  por- 
tions, sometimes  combined  with  foreign  substances.  Many  lava  flows 
have  margins  of  loose  blocks,  that  are  thus  described  by  Smyth  : — 
**  Cooling  and  hardening  on  the  surface,  cracking,  breaking  up,  and 
falling  forward  in  clinkery  masses  of  rattling  cinders  and  stones — such 
must  have  been  the  mode  of  progression  of  these  black  streams,  as 
with  many  of  the  Vesuvian  lavas  under  oculat  inspection."!  -And 
if  such  had  been  the  margin  of  the  ancient  flows  in  West  Galway, 
we  could  well  imagine  that  now  they  graduate  into  a  nodular 
rock,  not  a  normal  igneous  rock,  or  yet  a  typical  tuff.  Scrope,J  how- 
ever, and  others,  allude  to  the  spheroidal  and  concretionary  structure 
of  some  basalts,  and  some  of  these  rocks  might  possibly  have  so 
originated. 

The  nodular  hornblende-rocks  graduate  into  the  previously  de- 
scribed conglomeritic-schist  and  gneiss. 


•  Forbes  has  microBcopically  examined  one  of  these  schists,  and  proved  that  it 
belonged  to  the  derivate  rocks.     Microscope  in  Oeology,  pp.  13  and  16. 
t  "  Teneriffe,"  by  C.  Piaz«i  Smyth,  F.  R.  S.,  p.  249. 
X  "  VolcAnos,"  p.  Ill,  and  pp.  184,  &c. 


i 


KiKAHAN — On  Oranitic  and  other  Ingenite  Rocks,        121 

Foliated  felstone  or  gneUsyte  and  granitoid  felstone. — These  rocks  may 
occur  cuttiiig  across  tlie  stratification  of  the  metamorphic  sedimentary 
rock  as  dykes,  or  they  may  be  in  masses  or  beds.  The  most  common 
variety  of  the  foliated-felstone  is  a  gneissoid-rock  consisting  of  layers 
or  leaves  of  quartz,  felspar,  or  f elsite  iuid  mica,  apparently  similar  to 
the  rock  described  by  Cotta,  and  called  gneissyte  or  irrnptive  gneiss,* 

In  varieties,  amphibole  or  ripidolite  may  partially  or  wholly  replace 
the  mica;  pyrite  «dso  is  often  present.  Some  foliated-felstones  are 
schistose ;  usually  the  rock  consists  of  layers  of  f  elsite  and  mica,  amphi- 
bole or  ripidolite;  there  are,  however,  rocks  that  are  aggregates  of 
quartz  and  felsite  or  felspar — ^the  constituents  of  both  the  gneissoid 
and  schistose  varieties  depending  altogether  on  the  composition  of  the 
original  rocks. 

The  lines  of  foliation  usually  are  parallel,  or  nearly  so,  to  the  walls 
of  the  dyke,  but  at  other  times  they  are  oblique  or  even  spheroidal.  The 
most  prevalent  structures  in  felstones  were  enumerated  when  describ- 
ing those  rocks ;  and  on  a  comparison  of  the  foliation  in  gneissyte  with 
the  lines  of  structure  in  felstones,  a  remarkable  similarity  will  be  found, 
consequently  it  does  not  appear  unreasonable  to  suppose  that  the  folia- 
tion in  the  gneiss3rte  has  been  induced  by  the  most  prominent  lines  of 
structure  in  the  original  rocks.  In  places,  the  foliated  rocks  can  be 
traced  until  they  graduated  into  rocks  in  which  foliation  has  not  been 
developed.  Gneissyte  was  principally  noted  as  dykes  among  the  gneiss 
and  schist,  but  in  the  neighbourhood  of  Bama  there  is  a  foliated  felstone 
in  the  porphyritic-oligoclasic-granite  ( Galway -type-granite).  Its  occur- 
rence in  such  a  place  seems  to  be  remarkable,  and  h£u:d  to  explain,  never- 
theless, the  writer  of  this  essay  on  a  former  occasion  has  suggested  an 
explanation  for  the  phenomena.! 

Others  of  the  metamorphosed  felstones  are  devoid  of  foliation.  These, 
may  be  called  granitoid-felstone  from  their  appearance.}  They  are  a 
granular  compound  of  felsite  and  quartz ;  or  of  felsite,  quartz,  and  mica ;  or 
of  felsite,  queurtz,  mica  and  felspar,  and  from  the  latter  the  rock  graduates 
into  a  granite.  In  a  few  localities  amphibole,  or  a  mineral  that  appeared 
to  be  ripidolite,  was  noted  in  addition  to  the  mica.  In  more  than  one  place 
these  rocks  can  be  traced  until  they  graduate  into  a  felstone,  very  little 
if  at  all  altered.  Most  of  these  rocks  seem  to  have  been  originally  highly- 
eiliceous-felstones  (peiro  silex) ;  therefore,  they  for  the  most  part  have 
orthoclase  for  their  felspar ;  there  are,  however,  other  granitoid-f  elstones 
that  appear  originally  to  have  been  basic-felstones  (euryte),  and  these 
were  changed  into  rocks  in  which  oligoclase,  amphibole,  and  such  Kke 
minerals  are  essentials. 


•  Cotta,  1.  c,  p.  234. 

t  Journal  of  the  Boy.  Geol.  Soc.,  Ireland,  1871,  vol.  ui.,  p.  1.  They  may, 
however,  be  foliated  normal  felstones,  as  normal  foliated  intnisiye  granites  (as  at 
Newiy,  C5o.  Down)  occur  in  places. 

X  MaccuUoeh  describes  rocks  among  his  granites  that  evidently  are  similar  to 
these  rocks. 


122  Proceedings  of  the  Royal  Irish  Academy. 

The  gneissyte  and  granitoid-felstone  that  occur  in  bedded  masses 
are  more  or  less  hard  to  determine,  as  some,  especially  among  the 
gneiss,  are  very  similar  to  many  of  the  metamorphosed  sandstones 
and  grits.  They,  however,  generally  weather  with  a  white  crust  some- 
what like  a  felstone,  which  weathering  among  the  metamorphosed 
sedimentary  rocks  is  unusual  only  on  f clsitytes  and  felsitic-quartzytes. 
Moreover,  m  some  cases  a  rock  that  apparently  is  bedded,  when  care- 
fully traced  will  be  found  to  cross  or  intrude  into  some  of  the  associated 
bedded  rocks. 

Gbanitic  Bocks. — The  granitic  rocks  may  be  highly  siliceous,  or 
more  or  less  basic ;  both  of  these  groups  contain  rocks  that  are  intru- 
sive, the  latter  others  that  have  been  formed  in  situ  by  extreme  metamor- 
phic  action.  Previous  to  entering  into  the  description  of  the  typical 
granites,  the  elvanytes  or  quartz-porphyrites  should  be  enumerated 
and  described,  as  they  are  the  granitic-rocks  next  in  order  to  the 
plutonic-rocks. 

Ehanyte  or  quarts^  porphyry. — These  passage-rocks  between  the  plu- 
tonic-rocks and  the  typical  granites  are  idways  more  or  less  granitoid. 
They  seem  to  belong  to  the  granitic-rocks,  as  they  are  hypogene,  and 
consequently  never  are  associated  with  tuff  or  any  other  such  mechani- 
cally formed  accompaniment.  ^Nevertheless,  in  part  they  are  allied  to 
the  plutonic-rocks  as  they  graduate  into  them;  moreover,  at  the 
extreme  margin  of  wide  dykes,  also  in  small  dykes,  branching  from  a 
large  one,  a  rock  often  occurs  that  in  aspect  is  undistinguishable  from 
a  plutonic-rock.  These  compact  portions  at  the  walls  of  dykes  are  never 
more  than  a  few  inches  in  thickness.* 

Elvanytes  range  from  highly  siliceous  to  basic,!  according  as  they  are 
the  passage-rocks  from  felstone  or  whinstone  to  granite. 

Elvanyte  has  a  more  or  less  crystalline  felsitic  or  felspathic 
base,  usually  with  globules,  bleds,  or  crystals  of  quartz,  crystals 
of  felspar,  and  flakes  of  mica  or  ripidolite  or  crystals  of  amphibole ; 
pyrite  also  is  often  present,  beside  other  minerals,  generally  as 
accessories,  but  sometimes  locally  as  essentials.  In  all  elvanytes 
some  of  the  quartz  seems  to  have  crystallized  out  first,  but  some^ 
times  only  sparingly.  In  the  highly  siliceous  varieties  this  quartz 
is  characteristic  of  the  rocks,  while  in  the  more  basic  varieties 
it  is  often  scarcely  perceptible.  Scheerer  excludes  from  his  true 
granites  rocks  in  which  part  of  the  quartz  crystallized  out  before  the 
other  constituents,  as  will  be  seen  from  the  following  epitome  of  this 
eminent  geologist's  definition  for  granite : — ' '  The  crystals  of  felspar,  and 
others  not  containing  water,  crystallized  out  first ;  the  mica,  which  con- 

*  The  compact  portion  is  called  by  Cotta  the  base  or  mother-rock.  Rock  claasi- 
fication,  1.  c,  p.  214. 

t  There  are  granitoid-basic-rooke  very  siinilar  in  appearance  to  some  of  the  pre- 
viously mentioned  varieties  of  hornblende-rock ;  some  of  these  probably  belong  to  this 
group ;  however,  in  the  country  to  which  this  essay  refers  this  could  not  be  proved. 
There  are,  however,  as  will  be  hereafter  stated,  rocks  that  might  be  called  sycnyte, 
which  belong  to  this  group. 


KiNAHAN — On  Granitic  and  other  Ingenite  Bocks.        123 

tains  much  water,  probably  next ;  and  the  silex,  which  the  heated 
water  wonld  longest  hold  in  solution,  last."  Neyeitheless,  this 
opinion  does  not  seem  to  be  universal,  as  Cotta  and  others  place  such 
rocks  as  elvanyte  among  the  granitic-rocks.* 

The  base  may  be  green,  grey,  purple,  brown,  blue,  or  even  yellow- 
ish ;  the  latter  colour,  however,  se^ms  generally,  if  not  always,  to  be 
due  to  weathering.  The  base  usually  gives  the  colour  to  the  rock,  but 
it  may  be  more  or  less  modified  by  the  colour  of  some  of  the  contained 
minerals.  All  the  highly  siliceous  varieties,  and  some  of  the  basic, 
weather  with  a  more  or  less  smooth,  flowery  outline,  so  characteristic 
of  the  felstones,  and  not  with  the  rugged,  rough  aspect  of  a  granite ; 
some  amphibolic  or  pyroxenic  varieties,  however,  weather  rough. 
The  quartz  bleds,  globules,  or  crystals,  scattered  through  the  mass, 
range  from  mere  specks  to  the  size  of  peas,  or  even  larger,  in  some  of 
the  highly  siliceous  varieties  being  so  numerous  as  to  give  the  rock  a 
pisolitic  appearance.  They  internally  have  a  glassy  appearance  and 
fracture ;  on  some  of  the  blebs  the  crystal  faces  can  be  recognised, 
while  others  appear  to  be  minute  coated  balls.  The  latter  often  have 
a  radiated  structure,  and  in  some  there  is  a  minute  hollow  in  the 
centre,  t 

The  varieties  in  composition  of  the  elvanytes  that  were  observed  in 
this  country  are  highly-siliceous  (^qttartzitic-elvanyte),  having  numerous 
orthodase  crystals  {orthodasiC'elvanyte),  or,  perhaps,  oligoclase  crys- 
tals {oligoclasic'elvanyte) ;  mica  in  some  may  be  so  abundant  as  to  give 
a  character  to  the  rock  (micaceous-elvanyte),  or  that  mineral  may  be 
wholly  or  partially  replaced  by  amphibole  or  ripidolite  {homblendie- 
elvanyte  and  chloritiC'ehanyte).\  The  highly-siliceous  elvanytes  have 
orthoclase  for  their  felspar.  The  basic  elvanytes  usually  have  a 
trialinic  felspar  or  the  lime  orthoclase  (adularia),  with  which  ore 
associated  such  basic  minerals  as  amphibole,  pyroxene,  and  the  like. 

In  some  of  the  elvanytes  in  the  neighbourhood  of  Galway,  and  also 
in  the  island  of  Lettermullan,  many  of  the  orthoclase  crystals  (flesh- 
colour)  are  enclosed  in  an  envelope  of  light  green  felspar  (oligoclase  ?), 
somewhat  similar  to  the  Pinland  rock  that  has  been  called  Rapakivi 
granite  {Rapakivi-ehanyte). 


•  Jukes  classed  in  lus  elvanytes  the  rocks  called  by  Cotta  "  granitic-porphyry'* 
and  "  quartz-porphyry."  In  the  latter  ^roup  Cotta,  as  well  as  Jukes,  seems  to  include 
some  rocks  that  e-vidently  are  quartzitic-felstones ;  but  as  such  aro  not  hypogene- 
rocks,  they  do  not  properly  belong  to  this  group. 

t  The  latter  can  be  seen  with  a  pocket-lens.  I  have  tried  to  get  a  section  of 
one  to  examine  under  the  microscope,  but  as  yet  have  not  succeeded,  as  out  of 
numerous  slices  of  elvanyte  none  contained  this  peculiar  form  of  the  quartz. — \^NoU 
in  preM.^ 

X  Micaceous-elvanjte  would  be  called  by  some  geologists  mica-trap  ;  this  further 
shows  that  the  term  is  not  a  class-name.  Homblendic-elvanyte  would,  by  some, 
be  called  »yenyie  ;  this,  for  those  in  which  the  felspar  is  only  orthoclase,  is  cx)rrect ; 
in  many  of  them,  however,  orthoclase  is  not  the  felspar,  consequently,  for  such  rocks 
the  name  would  be  incorrect. 


124  Proceedings  of  the  Royal  Irish  Academy. 

In  structure  elvanytes  vary  ;  some  are  finely  crystalline,  so  as  to  be 
nearly  compact,  while  others  are  granular  or  granitoid,  the  latter  gra- 
duating into  typical  granite.  Elyan3rte  graduating  into  granite  is  well 
exemplified  in  the  neighbourhood  of  Kylemore.  Here,  south  and  south- 
west of  Bengooria  or  Diamond  Hill,  are  protrusions,  in  part  scarcely 
distinguishable  from  typical  granite,  nevertheless,  in  all  of  it  blebs  or 
crystals  of  quartz  that  were  developed  before  the  other  rock  consti- 
tuents can  be  detected,  more  or  less,  while  toward  the  margins  of  the 
masses  the  rock  is  a  typical  granitaid-ehanyte.  Moreover,  from  the 
tracts  extend  numerous  dykes,  some  being  large  and  others  small ;  all 
the  former  are  more  or  less  granitoid,  while  the  latter  are  finely  crys- 
talline or  nearly  compact,  some  apparently  merging  into  quartzitic-fel- 
stone.  Part  of  the  rock  in  mass,  although  granitoid,  has  the  typical 
weathering  of  elvanyte,  which  seems  due  to  all  the  quartz  and  felspar 
not  being  crystallized  out,  parts  of  these  remaining  undeveloped ;  and 
from  this  peculiar  weathering  the  Cornish  name  seems  to  be  derived 
(el,  oil  rock,  ban  or  van  white),  as  the  white  smooth  crust  has  a  marked 
contrast  when  compared  with  the  rough  weathering  of  granite. 

Some  rocks  like  elvanyte  are  gneissoid.  This  structure  may  possibly 
be  due  to  metamorphism  ;  as  in  the  neighbourhood  of  Galway,  in  one 
or  two  instances  it  has  been  proved  that  some  of  the  elvanyte  is  older 
than  some  of  the  typical  granite,  but  as  a  general  rule  the  elvanytes 
are  newer ;  and  in  the  country  north  of  Ballary  Harbour,  where  the 
rocks  are  only  slightly  altered,  there  are  large  *dykes  of  foliated 
elvanytcf ;  moreover,  they  were  only  observed  in  the  neighbourhood  of 
protrusions  of  granite,  and  may  possibly  be  connected  with  them.* 

My  friend  and  colleague,  R.  G.  Symes,  F.  R.  G.  S.  I.,  &c.,  seems 
to  have  been  one  of  the  first  who  pointed  out  the  graduation  of  granite 
through  elvanyte  into  felstone.  While  examining  the  rooks  adjoining 
the  north  shore  of  Galway  bay,  I  suspected  such  must  be  the  case, 
and  mentioned  my  opinion  in  the  Geological  Survey  Memoirs.  Since 
then  I  have  seen  the  gradation  in  various  localities. 

Granite. — Of  typical  granite  the  principal  varieties  in  composition 
will  be  found  in  the  following  list.  There  are  others,  some  being  very 
remarkable,  not  only  in  composition,  but  also  in  structure ;  however, 
they  are  only  varieties  of  the  rocks  enumerated. 

Typical  Granites, 

Basic  oligoclasic-granite  |  MetamorpMc  (Galway-typc-granite). 
•^  **  ( Intrusive  Omey-type-gramte). 

Highly  siliceous  ortholasic-  (  Metamorphic. 

granite.  ( Intrusive  (Oughterard-type-granite). 

•  The  country  between  these  dykes  and  the  granitic  masses  is  covered  with 
drift.  It  appears  remarkable  that  these  foliated  rocks  should  only  have  been  found 
hereabout  associated  with  other  granitic  dykes.  This  foliation  can  scarcely  be  due 
to  metamorphism,  on  account  of  the  unaltered  condition  of  the  associated  rocks. 


KiNAHAN — On  Granitic  and  other  Ingenite  Rocks,        125 

Haughton  divides  the  granites  of  Ireland  into  three  groups,  viz. : — 
I.  The  granites  of  Leinster ;  11.  The  granites  of  Mourne  and  Carling- 
ford :  and  III.  The  granites  of  Donegalf  Mago^  and  Galwag.  These 
belong  to  two  classes,  first,  intrusivey  containing  the  first  and  second 
groups ;  and  second,  non^intrusivey  containing  the  third  group.* 

Mr.  Deleese  "  also  distinguishes  two  kinds  of  granite,  one  irruptive 
and  the  other  metamorphic  ;  the  latter  taking  often  a  gneissoid  struc- 
ture.".! •  ... 

Haughton's  first  group  seems  to  be  nearly  identical  with  the  ortho- 
dasic  intrusive-granite,  while  the  oligoclasic  metamorphic-granite 
represents  his  tMrd  group. 

Metamorphic  oUgodastc-granite  (Galway-type-granite). — ^These  are  of 
metamorphic  origin  or  formed  in  situ  ;  that  is,  the  granite  is  due  to  the 
extreme  metamorphism  of  derivate  and  igneous  rocks  in  the  plac6,  in 
relation  to  the  associated  rocks  that  it  now  occupies,  and  was  not 
intruded  or  thrust  up  iuto  its  present  position. 

This  rock,  the  "  Gkd way-type-granite "  of  the  Memoirs  of  the 
Geological  Survey,  is  a  crystalline  porphyritic  aggregate,  having  as 
conspicuous  essentials  pink  or  fiesh-colour  felspar  (orthoelase),  greenish 
or  yellowiah  waxy  felspar,  white  felspar,  J  quartz,  black  mica 
(^lepidamelane  ?)y  white  mica  {muscovite  f),  and  pyrite  or  marcasite. 
The  common  accessories  are  amphibole,  titanite,  ripidolite,  epidote, 
chalcopyrite,  galenite,  flourite,  talc,  and  garnet.  The  first  three  of  these 
accessories  seem  locally  to  be  also  essentials.  Thus  in  the  Fttrhogh- 
type-granite  (called  after  Furbogh,  six  miles  west  of  Galway,  where  this 
variety  is  the  prevailing  rock),  amphibole  and  titanite  are  essentials ; 
in  other  localities  amphibole  and  ripidolite,  also  epidote,  are  not  uncom- 
mon :  the  latter,  however,  is  believed  to  be  due  to  decomposition. 
Fyrite  is  mentioned  among  the  essential,  as  it  seems  never,  or  on  very 
rare  occasions,  absent. 

The  orthoclase  usually  occurs  in  large  crystals,  often  twins,  some* 
being  over  two  inches  in  length ;  they  usually  give  the  poiphyritic 
character  to  the  rock ;  however,  in  a  few  places,  the  wlute  felspar 
may  do  so.  In  one  locality  (Furbogh)  some  of  the  large  fiesh-colour 
crystals  {orthoclase)  are  enclosed  in  a  white  felspar  envelope. 
The  amphibole  in  places  is  accompanied  by  titanic,  or  ripidolite,  or  by 
a  green  epidotic-looking  mineral,  the  hornblendic-granite  occurring  as 
irregular  subordinate  masses — ^the  variations  in  the  composition  of 
metamorphic  granite,  as  pointed  out  by  Haughton,  being  due  to 
the  different  rocks  from  which  it  was  formed.  In  places,  there  are 
irregular  and  vagrant  patches,  and  veins  of  a  variety,  **  very  coarsely 

*  For  a  resume  of  Doctor  Haughton*s  conclusioiifl  on  the  granitee  of  Ireland, 
■ee  W.  W.  Smyth's,  F.  R.  S.,  &c.,  Presidential  Address  to  the  Geol.  Soc.  Lond., 
Quar.  Jour.,  vol.  zziv.,  p.  bcxiv. 

t  Volcanos,  by  G.  P.  Scrope,  P.  R.  S.,  &c.,  second  ed.,  1862,  p.  300,  foot-note. 

X  Some  of  the  waxy  felspar  is  triclinic,  but  usually  it  is  more  or  less  amalga- 
mated with  a  variety  of  orthoclase,  probably  adularia ;  the  white  felspar  also  is 
probably  adularia. — [Note  added  in  the  press.'] 

R.  I.  A.  PROC  ,  HER.  II.,  VOL.  XL,  SCIENCE.  S 


126  Proceedings  of  the  Royal  Irish  Academy, 

and  irregularly  congtitutcd,  of  orthoclase,  quartz,  and  silvery  white 
mica,"  answering  Cotta's  description  for  the  rock  he  caHs  peymatyte.* 

In  some  places  the  crystal  of  felspar  are  very  large,  they  being  two 
inches  or  more  long.  This  class  of  rockf  in  places  may  have  been 
formed  subsequent  to  the  associated  granite ;  in  others  it  has  not,  as 
will  hereafter  be  pointed  out. 

Veins  of  segregation  ( Granityte),  always  fine,  are  not  uncommon, 
and  two  or  more  systems  may  occur  together,  their  different  ages  being 
known  by  their  entering  and  displacing  each  other. 

These  are  more  or  less  regular,  generally  having  an  angular 
arrangement,  apparently  occupying  lines  of  joints,  and  they  seem  to 
be  due  to  matter  which  has  segregated  from  the  liquid  or  semi- 
liquid  portions  near  the  interior  of  the  mass  having  been  pressed  up 
into  the  shrinkage  fissure  formed  in  the  consolidated  portion,  as  the 
latter  cooled,  each  successive  system  of  cracks  having  their  own 
veins. 

When  looking  over  an  cxplance  of  the  Galway -type-granite,  it  is 
not  unusual  to  find  the  large  crystal  of  felspar  lying  in  irregular 
parallel  lines,  while  towards  the  noith-east  and  north  margin  of  the 
great  tract  that  bounds  Gkdway  Bay  on  the  north,  the  rock  is  found 
gradually  to  become  more  and  more  foliated  {gneissoid  granite  or  grani- 
toid gneiss)^  until  eventually  it  graduates  through  gneiss  into  schist 
(see  Section,  Figure  S,  PI.  12).  Towards  the  south,  however,  in  the 
vicinity  of  Galway  Bay,  another  change  takes  place,  as  here  the  rock 
graduates  into  a  more  or  less  even-grained  granite,  in  which,  as  a  rule, 
none  of  the  felspar  is  porphyritically  developed.  This  even-grained 
granite  seems  to  extend  as  courses  into  the  porphyritic  granite,  while 
associated  in  places  -are  many  elvanytes.  It  may  be  here  remarked 
that,  in  the  immediate  neighbourhood  of  Galway,  there  are  many 
elvanytes,  as  a  rule,  in  large  dykes,  that  are  associated  with  courses  or 
dykes  of  granite,  all  usually  running  with  a  general  north  and  south 
bearing. 

The  conspicuous  essentials  of  the  even-grained  granite  are  in 
general  very  similar  to  those  in  the  porphyritic  variety,  but  not 
always ;  as  in  places,  courses  of  this  granite  vary  not  only  in  texture 
and  structure,  but  apparently  also  in  composition:  and  what  may 
perhaps  be  more  important,  in  one  place,  where  gneiss  overlies  these 
granites,  the  dip  and  strike  of  the  courses  seems  to  be  similar  to 
the  dip  and  strike  of  the  stratification  of  the  gneiss.  In  the  neigh- 
bourhood of  Furbogh  were  observed  patches  of  a  very  homblendic 
and  titanitic  granite,  in  which  there  is  none  of  the  flesh-coloured 
orthoclase,  or  white  mica,  and  only  a  little  black  mica.  Toward 
the  west  and  north-west,  the  Galway-type-granite  graduates  into  the 
Omey-type-granite. 

♦  Cotte,  1.  c,  p.  206. 

t  These  veins  probably  belong  to  the  class  called  Endogenous  bv  Hunt.     See 
p.  131. 


KiNAiiAX — On  Granitic  and  other  Ingenite  Rocks,         127 

To  the  north  and  north-east,  the  gneiBBoid-granite  seems  to  have, 
siinilar  constituents  to  the  typical  rock;  but  the  mica  and  quartz, 
with  part  of  the  felspar,  are  arranp:ed  in  leaves  or  plates,  while  the 
large  crystals  of  felspar  are  generally  arranged  rudely  parallel  to  the 
layers,  but  not  always,  as  they  often  cut  across  them ;  schistoid-beds 
also  occur  in  it.  The  foliation,  irrespective  of  the  dip  of  the  original 
rocks,  is  perpendicular,  or  nearly  so ;  but  the  strike  seems  always  to 
correspond  with  that  of  the  stratification  of  the  associated  gneiss. 
However,  as  the  rock  loses  its  granitic  character,  and  becomes  more 
and  more  gneissose,  the  original  dip  of  the  rocks  becomes  apparent. 

Among  the  metamorphic  derivate  rocks  of  the  barony  of  Ballyna- 
hinch  or  Connemara,  there  are  large  and  small  tracts  of  granitoid- 
gneiss,  the  rock  being  identical  with  the  gneissoid-granite,  forming 
the  north  and  north-east  limits  of  the  great  tract  of  Galway-type- 
granite.  These  tracts  always  occur  in,  and  naturally  might  be  consi- 
dered a  portion  of,  the  gneiss-Bwies ;  nevertheless,  in  some  places  the 
rock  loses  all  traces  of  foliation,  and  becomes  a  granite  undistinguish- 
ble  from  the  Gtdway-type-rock,  the  essentials,  accessories,  structure, 
and  aspect  being  identical. 

That  these  tracts  of  granitoid-gneiss,  or  gneissoid-granite,  are 
highly  metamorphosed  parts  of  the  gneus-serieSf  and  not  accidental 
intrusions  of  granite,  to  me  seems  proved,  as  the  one  rock  not  only 
graduates  into  the  other,  but  also  in  places  schistoid  layers  will 
traverse  the  granitic  rock,  these  layers  having  a  strike  and  dip  agree- 
ing with  those  of  the  stratification  of  the  associated  gneiss  and  schist. 
Such  changes  in  isolated  portions  seem  due  to  portions  of  the  derivate 
rocks,  on  account  of  the  materials  composing  them  being  more  easily 
changed  than  the  associated  strata.  This  is  very  conspicuous  at 
Forlome  Point,  Co.  Wexford,  where  beds  of  granite  are  found  associated 
and  interstratified  with  beds  of  incipient  micasyte,  homblendyte  and 
talcyte. 

The  change  from  gneiss  into  granite  is  most  remarkable  in  the  con- 
glomeritic  and  nodular  rocks.  As  previously  pointed  out,  all  former 
structure,  except  the  strike  of  the  stratification,  is  generally  oblite- 
rated in  the  granitoid-gneiss,  the  only  exception  apparently  being, 
that  some  of  the  blocks  in  conglomeritic  gneiss,  more  or  less  modified, 
may  still  appear.  This,  however,  is  not  generally  the  case,  for,  as  the 
rocks  become  moi;e  and  more  gneissic,  the  blocks  usually  become  elon- 
gated, with  the  foliation  curling  more  or  less  round  them,  but  subse- 
quently the  foliation  becomes  parallel  in  lines,  the  matrix  having  a  fine 
texture,  while  that  of  the  blocks  is  coarse  (Fig.  0,  PI.  10) ;  the  boundary 
between  each  being  still  apparent ;  and  as  the  change  progresses,  all 
seem  to  differ  very  little  in  texture,  or  rather  one  merges  so  gradually 
into  the  other,  that  there  is  no  difference  discernible,  till  eventually  all, 
or  all  conspicuous  foliation,  disappears,  and  the  rock  becomes  a  typical 
granite. 

Associated  with  the  tracts  of  hornblende-rock  {tnetamarphosed  whin- 
stone  and  ettryte)  are  smaller  or  larger  masses  of  granite,  similar  to  the 


128  Proceeding9  of  the  Royal  Irish  Academy, 

Galway-type-granite.  In  some  places  it  is  possible,  although  not 
very  probable,  that  outburst  of  granite  may  have  occurred  in  these 
places ;  this,  however,  appears  rarely,  if  ever,  to  have  happened,  as  in 
all  cases  one  kind  of  rock  seems  to  graduate  into  the  other.  This 
granite  has  the  same  essentials  and  accessories  as  the  Galway-type- 
granite,  is  similar  in  texture  to  the  coarse  varieties,  and  to  me  it  appears 
probable  that  similarly,  as  the  sedimentary  rock,  change  into  granite, 
BO  may  also  the  whinstones  and  eurytes.  K  such  may  happen,  these 
masses  of  oligoclasic-granite  may  only  be  extremely  metamorphosed 
portions  of  the  original  outbursts  of  plutonic  rock. 

Indnrnve-oligoclasie-granite  (Omey-type-granite). — ^Although  some 
of  the  oligoclasic-granite  may  have  been  formed  in  situ,  part  is 
undoubtedly  intrusive,  such  as  the  masses  at  Omey,  Roundstone,  &c., 
which  appear  as  protrusions.  To  the  large  tract  near  Galway,  and 
also  to  the  small  tracts  since  mentioned,  there  are  regular  bound- 
aries, while  to  these  protrusions  the  boundaries  are  more  or  less  irregu- 
lar; besides,  instead  of  the  granite  graduating  into  gneiss,  it  may 
be  associated  with  either  gneiss  or  schist,  brealang  up  through  them ; 
consequently  the  metamorphic  sedimentary  rocks  may  dip  at  or 
oblique  to  it,  but  can  never  lie  conformably  on  it.  Moreover,  it  sends 
veins  into  those  rocks,  proving  that  this  variety  must  be  a  true  intru- 
sive rock. 

In  some  places  this  oligoclasic-granite  is  in  juxtaposition  with  the 
gneiss  and  schist,  but  in  many  cases,  more  especially  if  the  boundary 
is  very  irregular,  veins  and  masses  of  the  orthoclasic,  or  highly-sili- 
ceous-granite,  intervene.  In  such  cases  the  adjoining  gneiss  and 
schist  are  usually  cut  up,  displaced,  and  traversed  in  all  directions  by 
regular  and  irregular  veins  of  the  latter  granite,  from  mere  strings  to 
yards  in  width,  sometimes  forming  such  a  close  irregular  network 
that  it  is  impossible  to  draw  an  exact  boundary  between  the  granites 
and  the  metamorphosed  sedimentary  rocks. 

The  intrusive-oligoclasic-granite  is  very  similar  in  aspect  and  com- 
position to  the  oligoclasic-granite  of  metamorphic  origin ;  nevertheless, 
after  the  rocks  are  studied  and  known,  certain  peculiarities  will  be 
learned,  that  are  always  distinctive  marks  between  the  two  varieties. 

Oligoehuic-granite,  Oligoclasie'graniie, 

(Metamorphic.)  (Intrusive.) 

Amphibole,  titanite,  and  such  Amphibole,  titanite,  and  such 

like  minerals,  are  locally  essen-  like  miner5ils,  seem  ever  to  be  es- 

tials,  while  often  they  are  acces-  sentials,  and    sometimes   are  not 

series.  accessories. 

Gneissoid,  or  schistoid   layers  Gneissoid,  or  schistoid  layers  or 

or  courses,  sometimes  occur  in  the  courses,  never  occur,  while  lentels 

mass  of  the  rock,  while  lentels  and  irregular  patches  are  rare, 
and  irregular  patches  are  not  un- 
common. 


KiNAHAN — On  Oranitic  and  other  Ingenite  Rocks.       129 

The  granite  graduates  tbrough  The  granite  never  graduates 
gneiss  into  schist.  into  gneiss  or  schist. 

A  foliation  more  or  less  con-  No  foliation.* 

spicnoiis  is  often  present,  or,  if 
it  is  absent,  the  hurge  crystals  of 
felspar  are  often  arranged  in  lines, 
not  perhaps  visible  in  small  pieces, 
but  often  very  conspicuous  when 
the  rock  is  viewed  in  mass. 

Nearly  always  porphyritic  and  Often  more  or  less  evenly  crys- 
coarsely  crystalline.  The  felspar  talline,  none  of  the  felspars  being 
that  is  uBuaUy  conspicuously  de-  conspicuously  developed.  When 
veloped  being  the  pinkish  or  flesh-  porphyritic,  the  white  felspar 
colour,  rarely  the  white.  (aduliuria)  often  gives  the  charao- 

ter,  and  sometimes  the  green. 
Kever  graduate  into  elvanyte.  May    graduate  into    elvanyte, 

and  through  elvanyte  into  f  elstone 
(euryte),  or  perhaps  even  whin- 
stone. 

Metamorphte-orthoclaBiey  or  hiphfy-ailteeous^grantte. — ^The  rocks  be- 
longing to  tiiis  group  may  occur  as  masses,  dykes,  or  beds,  according  to 
the  position  the  plutonic  rocks,  from  which  they  were  altered,  occupied. 
Usually  they  are  of  a  fine  even  texture,  and  in  some  it  is  probable  all 
the  felspar  and  quartz  have  not  crystallized  out  from  the  original 
felsitic  mass,  such  a  rock  being  the  passage-rock  into  granitoid- 
felstone.  These  rocks,  when  weathered,  have  not  the  well-marked, 
rough,  rugged  aspect  of  a  typical  granite,  nor  yet  the  smooth  weather- 
ing of  a  f  elstone,  but  rather  a  mixture  of  both,  like  the  weathering  of 
a  felspathic  sandstone.  When  typical,  the  principal  minerals  they  con- 
sist of  are  quartz,  orthoclase,  and  mica,  pyrite  also  being  usually 
present ;  such  rock  being  metamorphic-petrosilex,  or  orthoclase-f  elstone. 
'From  being  highly-siliceous  they  may  graduate  into  a  metamorphic-oUgo- 
dasic-granite,  or  a  homblendic-granite,  following  the  different  grada- 
tions of  the  plutonic  rocks,  from  which  they  originated.  In  rocks  of 
this  group  it  is  not  unusual  to  find  lines,  or  a  liban,  having  an 
aspect  somewhat  like  stratification  due  to  bands  of  different  colour, 
texture,  and  perhaps  also  composition.  The  bands,  or  layers,  may  be 
coarser  or  finer  than  the  rest  of  the  rock,  or  they  may  be  more 
micaceous,  quartzitic,  or  felsitic,  or  they  may  contain  minerals, 
not  essentials  otherwise,  of  the  rock.  They  are  probably  due  to  a 
structure  in  the  original  rock,  perhaps  the  lines  of  viscid-fusion,  or 

*  In  thifl  area  there  aeema  to  be  no  foliation,  or  trace  of  foliation,  nevertheless  in 
eertain  oligoclasic  granites,  north-cast  of  Castlebar,  county  Mayo,  and  apparently 
belonging  to  this  variety  (as  they  occur  in  dykes  and  large  sewers),  there  is  a  distinct 
foliation.  As  I  never  carefully  examined  these  Castlebar  n>ck9  I  cannot  give  par- 
ticulan  about  them. 


130  Proceedings  of  the  Royal  Iriah  Academy. 

such  like.  In  the  vicinity  of  Galway,  the  late  Mr.  J.  Beete  Jukes 
pointed  out  that,  in  some  wide  courses  or  dykes,  the  outside  portions 
were  granitic  rocks,  while  the  interior  was  a  felstone,  seemingly  prov- 
ing that  the  change  must  be  due  to  metamorphic  action. 

Thisvariety  of  granite  often  is  found  associated  with  felsitic-quartzyte 
and  quartzitic-felsityte,  and  often  appears  to  graduate  into  the  former. 
For  which  reasons  it  seems  probable  that  some  at  least  of  those  rocks 
originally  were  either  felstone  or  felsitic-tuffs.* 

Mac  Culloch  seems  to  have  classed  together  this  granite  and  grani- 
toid-fclstone  as  different  varieties  of  one  kind  of  rock.f  Of  the  latter, 
he  says,  '*  This  variety  is  never  peifect,  as  it  contains  the  same 
minerals"  [quartz,  felspar,  and  mica],  "  without  form ;"  while  in  his 
first  division  of  the  granite,  he  includes  a  rock,  the  description  of 
which  would  answer  for  felsitic-quartzyte  or  quartzitic-granitoid- 
felstone.J 

Intruswe-arthoclasiCf  or  highly'Siliceaus-granite  (Ouyhterard-type- 
granite), — This  rock  only  occurs  as  intrusive  masses,  dykes  or  pipes. 
Jukes  pointed  out  that,  in  West  Galway,  when  in  mass,  it  always 
occupied  low  ground,  while  in  the  adjoining  high  ground,  when  it 
appeared,  it  was  as  dykes,  pipes,  or  small  protrusions.  This  pecu- 
liarity he  had  also  observed  in  Newfoundland,  and  other  places,  from 
which  he  concluded  that,  being  a  ^oep-seated  rock,  it  was  exposed 
only  in  low  ground,  when  the  superior  rocks  had  been  denuded  away ;  it, 
however,  also  extended  under  the  adjoining  high  ground,  as  was 
proved  by  the  dykes  or  off-shoots  from  it,  but  was  still  unexposed, 
denudations  having  failed  to  remove  the  covering  rocks.  According 
to  this  view,  the  deeper  and  more  extensive  the  denudation,  so  much 
larger  ought  the  tract  of  this  orthoclasic-granite  to  be. 

The  rock,  as  just  stated,  has  two  characters — one  massive,  and  the 
other  a  vein-rock,  and,  when  found  in  these  different  positions,  its 
composition  seems  to  vary.  Under  all  conditions  the  rock  appears 
never  to  contain  oligoclase  as  an  essential,  and  when  in  veins  or  pipes 
it  appears  usually  to  be  a  crystalline  aggregate  of  orthoclase,  quartz, 
and  a  greenish  mineral,  which  is  probably  an  earthy  mica,  or  perhaps 
ripidolite,  with  more  or  less  pyrite  or  marcasite.  The  greenish 
minend  in  places  is  undoubtedly  a  mica ;  but  in  other  places  it  has 
very  much  the  aspect  of  ripidolite,  and  possibly  both  minerals  may  be 
present.  When  in  tracts,  and  wide  veins  or  courses,  the  conspicuous 
constituents  seem  to  be  orthoclase,  quartz,  black  mica,  white  or  green 
mica,  and  pyrite  or  marcasite,  while  the  principal  accessories  are 
ripidolite,  galenite,  chalcopyrite,  barite,  calcite,  flourite,  molybdenite, 
&c.    These  often  occur  in  nodules,  lentils,  and  geodes,  with  lenticular 


*  It  was   previously  mentioned  that  some  of  the   rocks  classed  as  felsitic- 
quartzyte  originally  may  not  have  been  sedimentary  rocks. 

t  Mac  Culloch,  pp.  236  and  237.    Granite.    Second  division.    A.  a.  and  A.  d. 
{  Id.,  p.  234.     B.  a. 


KiNAHAX — On  Granitic  and  other  Ingenite  Rocks.        131 

patches  of  a  green  mineral,  called  by  the  miners  peach  ;*  also  with 
drusy  cavities,  or  small  vugs,  lined  with  crystals  of  quartz. 

The  rocks  in  the  veins  may  vary.  In  some  places,  so  siliceous  as 
to  look  like  quartzyte,  and  in  a  few  it  is  a  finely  crystalline  white 
rock,  in  which  the  quartz  and  mica  arc  so  minute  that  they  can  scarcely 
be  detected  by  the  naked  eye.  In  a  dyke  on  Shaunaunnafeola,  the 
centre  is  a  finely  crystalline  aggregate  of  quartz,  orthoclase  and 
black  mica,  while  the  outside  portions  near  the  walls  are  coarsely 
crystalline  compound  of  quartz,  orthoclase,  white  mica,  and  pyrite,  the 
latter  constituent  being  conspicuously  abundant.  This  vein  was  in  a 
neighbourhood  where  there  are  granites  that  are  evidently  metamor- 
phosed felstones,  and  possibly  it  may  also  belong  to  that  class.  In  a 
few  veins,  part  of  the  mica,  white  probably  muscovite,  has  a  plumose 
arrangement,  as  if  plumes  of  feathers  were  pasted  down  on  surfaces  of 
the  rock.  The  surfaces  in  those  places  where  this  arrangement  was 
noted  were  parallel,  or  nearly  so,  to  the  walls  of  the  veins.  This 
variety  appears  to  be  similar  to  the  rock  described  by  Jukes,  and  called 
plumose-^am'te. 

North-cast  of  Becess,  in  the  townland  of  Derrynea,  there  is  a  vein, 
having  in  the  centre  a  coarsely  crystalline  rock,  while  towards  the 
walls  the  rock  is  of  a  fine  texture.  In  the  hill  called  Lisoughter,  and 
also  in  other  places  in  the  barony  of  Ballynahinch,  peculiar  veins  were 
observed,  being  very  coarsely  crystalline,  the  quartz  and  the  felspar 
occurring  in  masses  often  the  size  of  a  man's  fist,  while  the  mica  is 
proportionally  large.  In  these  rocks  usually  the  mica  is  of  a  silvery 
palish  olive-green  or  a  whitish  colour,  but  black  mica  may  also  occur 
in  small  flakes.  The  large  mica  is  sometimes  most  peculiarly  arranged, 
so  that  on  weathered  surfaces  the  edges  of  the  flakes  have  angular 
forms,  as  if  the  rock  was  inscribed  with  some  kinds  of  written  charac- 
ters. In  other  veins,  that  appear  allied  to  those  last  described,  and 
always  when  they  traverse  or  are  in  juxtaposition  with  limestone, 
patches  may  lose  all  their  mica,  while  the  quartz  and  felspar  are  arranged 
like  Hebrew  characters,  answering  the  description  of  the  rock  that  has 
been  called  graphic  granite.\  The  granite  veins  last  described  are  evi- 
dently different  to  the  first,  and  seem  to  be  newer  than  them.  Possibly 
they  may  belong  to  the  class  called  endogenous  by  Hunt,  while  the 
others  belong  to  his  exotic  rocks. \ 

The  granite  in  mass  may  also  have  varieties.     In  some  places  it 

*  The  true  blue  peach  of  the  miner  is  ripidolite,  and  the  mineral  in  these  nests 
is  very  like  it  in  aspect  and  feel,  but  it  has  not  been  analysed. 

t  Hunt  mentioned  veins  of  graphic  granite  associated  with  limestone  among  the 
American  roclu.  {American  Journal  of  Science  and  Arts,  Third  Series,  vol.  i., 
No.  3,  p.  183). 

{  These  veins  I  believe  not  to  be  true  granite  dykes,  but  rather  to  belong  to  tlip 
class  called  "  granitic-veinstone"  by  Hunt.  I,  however,  here  describe  them,  aa 
other  authorities  class  them  with  the  tnie  granites.  The  vein  rock  just  described 
in  Derrynea  may  also  belong  to  Hunt's  "  endogenous  rocks." — Report  Geol.  Survey, 
Canada,'  I860,  p*  192. 


132  Proceedings  of  the  Royal  Irish  Academy. 

appears  to  lose  all  its  quartz  and  mica,  and  to  merge  into  a  crystalline 
felspathic  mass  {felsitic  granite),*  The  aspect  of  this  rock  is  well 
described  by  Cotta — *'  a  rock  of  compact  texture,  about  the  hardness 
of  felspar,  with  dull  or  smooth  conchoidal  or  fissile  structure  ;  colour, 
yellowish,  reddish,  grey,  greemsh,  or  bluish,  weathering  white."  The 
loss  of  the  quartz  and  mica  is,  howeyer,  more  apparent  than  real,  for 
on  a  close  examination  with  a  lens  both  may  be  detected,  always  very 
minutely  and  often  sparingly  developed.  In  another  variety  the  rock 
appears  to  lose  its  felspar  and  to  become  a  crystalline  granular  compound 
nearly  solely  of  quartz  and  ixAQSL{qtMrlMiti€  granite).]  This  rock  undoubt- 
edly is  very  quartzose,  and  perhaps,  although  closely  allied  to  them, 
ought  to  be  excluded  from  the  true  granites ;  for  although  in  general  a 
little  felspar  can  be  detected,  that  mineral  often  appears  to  be  absent, 
and  when  present,  presents  more  the  appearance  of  an  accessory  than  an 
essential.  In  some  places  even  the  mica  also  is  unapparent,  the  rock 
being  very  similar  to  the  rocks  at  Bray  Head,  Co.  Wicklow,  and  called 
quartz-rock  by  Jukes.  These  quartzose-rocks  are  peculiar,  and  hard  to 
explain.  At  Curraun,  immediately  south  of  Maam  Bay,  the  N.  W.  arm 
of  Lough  Corrib,  and  in  other  places,  the  quartzose  rock  undoubtedly 
graduates  into  the  intrusive  highly-siliceous  or  orthoclasic  granite,  but 
in  some  places  the  relations  between  the  quartzose-rocks  and  those 
associated  with  it  are  very  obscure.  At  Canrower  and  Croaghna- 
doosh,  both  in  the  vicinity  of  Oughterard,  masses  of  this  rock  occur,  seem- 
ingly in  connection  with  the  Oughterard-type-grauite,  but  the  coat  of 
bog  that  covers  so  much  of  that  country  prevents  them  from  being  pro- 
perly examined.  In  both  of  these  places  the  quartzose-rock  is  foliated, 
and  apparently  identical  with  quartzyte  that  in  other  parts  of  this 
country  is  undoubtedly  metamorphosed  sedimentary  rock.  However,  in 
these  two  places  the  quartzose  rock  quite  disagrees,  as  to  strike  and 
.  dip,  with  all  the  schists  and  gneiss  in  its  vicinity,  and  as  the  exposures 
are  in  irregular  patches,  they  scarcely  could  have  been  brought  into 
their  present  positions  by  faults.} 


♦  Felsite-rock  of  Cotta,  p.  220. 

t  Seemingly  the  rock  cedled  greisen  by  Cotta,  pp.  207  and  321. 

X  All  the  detaiU  in  relation  to  these  exposures  of  quartzoee-rock  are  given  in 
the  Geological  Survey  Memoir,  ex-sheet  105,  pp.  33,  39,  to  which  the  reader  may 
be  referred. 


KiXAHAN — On  Granitic  and  other  Ingenite  Hocks.        133 


Pakt  II. 

Suggestions  to  account  for  the  Origin  of  the  Granitic  and  other  Hypogene 

Bocks. 

In  the  preceding  part  of  this  essay  it  was  demonstrated  that  the 
whinstones  may  graduate  through  euryte  into  fclsyte  {petro-silex  or 
highly  siliceous  felstone),  while  these  plutonic  rocks  (whinstones  and 
felstones)  graduate  into  the  granitic  rock  and  through  elvanyte  into 
typical  granite ;  the  granitic  rocks  being  of  different  types,  some  being 
more  basic  than  others ;  and  as  there  are  basic  and  highly  mliceous  plu- 
tonic rocks,  so  also  in  the  granitic  rocks  some  elvanytes  and  granites  are 
basic,  while  others  are  highly  siliceous.  It  has  also  been  shown  that 
all  normal  rocks,  whether  derivate  or  igneous,  may  be  metamorphosed ; 
at  first  becoming  schistose,  second  gneissic,  and  finally  granitic,  the 
granites  varying  in  accordance  with  the  nature  of  the  constituents 
composing  the  rocks  previous  to  their  being  metamorphosed. 

Before  proceeding  further,  and  for  the  convenience  of  reference 
hereafter,  the  ingenite  rocks  in  this  area  may  be  divided  into  seven 
groups,  namely,  i.,  the  sehist-series ;  n.,  the  gneiss-series:  ni.,  the  non- 
intrusive-oligoelasic  granite ;  iv.,  the  intrusive-oligoclasie  granite ;  v.,  the 
orthochisie  granite  ;  tl.^  the  elvanyte;  vn.,  the  plutonic  rocks*. 

It  seems  to  be  now  generally  allowed,  that  all  granitic  and  other 
ingenite  rocks  were  formed  from  previously-existing  rocks,  the  hypogene 
at  a  depth  beneath  the  earth's  surface,  but"  the  volcanic  and  plutonic 
rocks  at  or  close  to  the  present  or  a  former  surface  of  the  globe. 

Some  of  the  hypogene  rocks  {granitic  rocks)  must  at  one  time  have 
been  more  or  less  fused  and  liquified,  while  others  {gneiss  and  schist) 
were  never  fused  or  liquefied,  but  were  more  or  less  changed  by  heat, 
either  wet  or  dry.  Wet  heat,  judging  from  the  rocks  of  AVest  Galway 
and  Mayo,  would  seem  to  be  the  more  probable ;  for  in  all  the  schist, 
gneiss,  and  non-intrusive  granite,  the  original  joint-lines,  as  previously 
mentioned,  are  either  sealed,  or  a  thin  portion  of  the  rock  adjoining  the 
joint  walls  is  silicefied  and  indurated,  as  if  by  being  percolated  by  steam 
charged  with  silex  or  some  such  substance  (figs.  G.  H.  PL  9  and  P. 
PI.  10). 

If  we  suppose  that  at  a  certain  distance  beneath  the  surface  of  the 
earth  all  rock  becomes  fused  and  liquefied,  the  rocks  in  the  zone  above 
the  melting  point  would  be  fully  mineralized,  but  not  liquefied,  while 


*  In  this  table  the  metamorphosed  plutonic  rocks  might  be  ignored,  as  they 
do  not  affect  the  following  arguments — nevertheless,  all  of  them,  excepting  the 
metamorphic  orthoclasic  granite,  are  included  in  the  tabove  classification.  The 
hypogene  rocks,  as  the  name  implies,  were  formed  at  a  depth  beneath  the  surface  of 
the  earth,  and  under  a  pressure  more  or  less  great ;  the  granitic  rooks  having  been 
fused  and  subsequently  cooled,  and  consolidated,  prior  to  their  being  exposed  by 
denudation  at  the  present  surface  of  the  earth. 

&.  I.  A.  PROC,  SER.  U.,  VOL.  II.,  BCIBNCB.  T 


134  Proceedings  of  the  Royal  Imh  Acadefny. 

each  successive  stratum  would  in  general  be  less  and  less  alPected  ;* 
and  if  the  rocks  while  in  these  conditions  began  to  be  raised, 
or  in  any  other  way  removed  out  of  the  influence  of  the  heat,  appa- 
rently there  would  be  conditions  to  account  for  the  formation  of  all 
kinds  of  ingcnite  rocks. f 

The  stratum  that  included  all  the  rocks  which  were  altered,  but 
not  fused,  would  contain  the  metamorphosed  rock ;  the  upper  portion 
of  the  rocks  belonging  to  the  schist-serieSf  and  the  lower  part  to  the 
gneiss-series.  Below  this  stratum,  in  the  zone  where  the  rocks  were 
fully  mineralized,  but  not  liquefied,  there  would  be  a  non-intrusive  granite 
rock  formed,  which  would  remain  in  its  original  position  as  regaids  the 
overlying  rocks,  but  its  nature  and  constituents  would  be  quite 
changed.  Below  the  melting  point  would  be  a  mass  of  fluid,  from 
which  all  the  intrusive  rocks  would  come.  Furthermore,  rocks  formed 
under  such  conditions  would,  as  in  nature,  have  no  hard  lines  of  de- 
marcation, the  lowest  members  of  each  graduating  into  the  upper  por- 
tion of  the  group  next  below  it. 

The  formation  of  the  non-intrusive  groups  of  hypogene  rock  has 
been  suggested,  but  there  still  remain  the  intrusive  rocks  to  be 
accounted  for.  As  the  heat  became  less,  the  liquified  portion  would 
cool  and  consolidate  imder  various  conditions,  consequently  forming 
rocks  not  only  different  in  aspect,  but  also  in  composition.  At  the 
first,  two  magmas  would  form — a  basic  above,  and  a  highly  siliceous 
below.  As  the  superincumbent  rocks  cooled,  cracks  and  other  fissures 
should  form,  into  which  portions  of  these  magmas  ought  to  be  forced 
by  the  pressure  of  the  overlying  mass,  and  also  by  the  escape  of  pent- 
up  gases  and  steam.  These  intrusions,  according  to  the  magma  from 
which  they  came,  ought  to  be  basic  or  highly  siliceous,  and,  if  forced  to 
the  earth's  surface,  they  would  cool  and  consolidate,  under  little  or  no 
pressure,  forming  the  different  varieties  of  plutonie  and  volcanic  rocks, 
while  the  portions  that  solidified  between  their  source  and  the  earth's 
suif ace  would  become  ehanyte,  a  granite  and  hypogene  rock,  but  not  a 
typical  granite,  as  some  of  the  silex  crystallizes  out  before  the  other 
rock  constituents. 

There  now  only  remains  the  intrusive  granites  to  be  formed  from 
the  residue  of  the  fliiid  magmas,  and  the  conditions  imder  which  these 
would  cool  have  to  be  considered.  The  more  acid  magma  should  cool 
slower  than  the  bacdc ;  therefore,  there  ought  to  be  two  distinct  rocks 
forming  the  magma ;  that  cooled  first  becoming  a  basic  rock  {oligoclasie 
granite),  while  the  other,  that  took  longest  to  cool,  would  form  the 
orthoelasic,  or  highly-siliceous  granite, 

*  In  Bome  rare  uutances,  as  previouBly  mentioned,  beds  or  portions  of  beds 
might  be  changed  into  granite  while  the  associated  rocki  above,  below,  and 
aiound  were  only  changed  into  gneiss  or  even  schist. 

t  Since  this  essay  was  read,  Ptofessor  le  Conte  has  jpublished  a  most  instractire 
paper  on  the  *'  Features  of  the  Earth's  Surface"  (American  Journal  of  Science  and 
Art,  third  series,  vol.  iv.},  which  bears  on  this  subject,  and  to  which  tiie  reader  is 
referred.     [Nots  in  presa.] 


KiNAHAX  —  Ou  Granitic  and  other  Ingenite  Rocks.        135 

Either  of  these  kinds  of  granite  would,  at  any  time  prior  to  their 
final  solidification,  be  liable  to  form  intrusive  masses  or  Teins,  being 
forced  up  into  fissures,  cracks,  or  any  other  kind  of  **  shrinkage  fissure," 
or  vacancy  formed  during  the  cooling  of  the  overljring  rocks,  the 
resulting  rocks  being  respectively  oligoclasic  or  orthoclasic  granite, 
according  to  the  magma  from  whence  they  came.  Furthermore,  after 
the  mass  of  either  the  oligoclasic  or  orthoclasic  granite  had  cooled, 
there  would  still  be  centres  containing  unsolidified  portions,  that  at  any 
time  would  be  liable  to  be  forced  up  into  the  shrinkage  fissures  as  the  mass 
cooled.  The  veins,  Oranitfte,  thus  formed  would  necessarily  be  more  sili- 
ceous than  the  associated  rock-mass ;  but  in  the  oligoclasic  granite, 
although  different  from  the  associated  rock,  they  might  be  nearly  similar, 
and  scarcely  distinguishable  from  the  orthoclasic  granite ;  however,  such 
veins  in  the  orthoclasic  granite  would  be  quite  distinct,  being  more 
siliceous  than  the  mass.  In  this  way  a  solution  for  the  formation  of 
the  quartzitic  granite  might  be  suggested ;  for,  if  we  could  imagine  a 
fluid  centre  becoming  more  and  more  siliceous  as  zone  after  zone 
cooled,  the  residue  finally  might  be  so  siliceous  as  to  be  similar,  or 
nearly  similar,  in  composition  to  quartzyte. 

If  the  granitic  and  other  ingenite  rocks  were  formed  under  circum- 
stances similar  to  those  above  suggested,  all  the  relations  between  the 
different  rocks  could  be  easily  explained.  In  West  Galway,  and 
South-west  Mayo,  these  all  graduate  through  other  rocks  into  each 
individual  rock,  yet  none  of  them  pass  suddenly  into  a  different  class 
lock — each  must  graduate  through  the  intervening  passage-rocks.  A 
schist  must  graduate  through  a  gneiss  into  a  non-intrusive  oligoclasic 
granite ;  a  gneiss  through  a  non-intrusive  oligoclasic  granite  into  an 
intrusive  oligoclasic  granite — ^a  non-intrusive  oligoclasic  granite  through 
an  intrusive  oligoclasic  granite  into  an  intrusive  orthoclasic  granite, 
and  the  latter  rock  through  an  elvanyte  into  a  plutonic  rock,  while 
among  the  latter  class  of  rocks  a  petroailex  must  graduate  through  an 
euryte  into  a  whinstone ;  all  the  other  graduations  are  similar,  there- 
fore, it  appears  unnecessary  to  enumerate  them,  and  such  changes  are 
all  accounted  for  by  the  above  suggestions.*  The  volcanic  and  plutonie 
rocks  would  have  to  range  from  basic  to  highly-siliceous,  according  to 
the  zone  and  time  from  and  at  which  they  were  intruded ;  so  would 
the  elvanyteSf  'and  so  would  the  intnMwe  granites.  The  granite  formed 
in  Situ  would  be  very  varied  in  its  composition,  on  account  of  the 
various  rocks  from  which  it  originated ;  yet  it  would  graduate  into 
intrusive  granite,  and  so  form  one  of  the  connecting  links  between  the 
plutonic  and  the  metamorphic  sedimentary  rocks. 

The  plutonic  and  volcanic  rocks,  being  surface-formed,  should  only 
be  found  among  surface-rocks;  but  as  all  may  at  some  time  or  other  be 
at  the  surface  of  the  earth,  they  are  found  breaking  up  through  all 


*  In  another  place  a  list  is  given  of  the  changes  remarked  in  the  rocks  of  thii* 
country. — Journal  Roy.  Geol.  8oc.  Ireland,  vol.  iii.,  1871,  p.  8. 


136  Proceedings  of  the  Royal  Lnsh  Academy. 

varietieSy  but  only  interstratified  with  those  that  are  surface-formed. 
Elvanyte,  on  the  other  hand,  is  a  hypogene  rock,  and,  as  its  natural 
place  is  near  the  granite,  it  should  more  frequently  occur  among  the 
metamorphic  rocks.  This  seems  to  be  the  case ;  for,  years  ago,  while 
reading  different  accounts  of  tracks  of  metamorphic  rocks,  but  espe- 
cially Logan's  reports  on  those  of  Canada,  I  was  struck  with  the 
frequent  occurrence  of  elvanyte  among  them.  They  do,  however, 
range  into  other  strata.  In  Yar-Connaught,  although  they  all  occur 
associated  with  the  metamorphic  rocks,  yet  many  of  them  apparently 
have  no  connection  with  that  group,  or  the  Galway  type  granite, 
as  for  instance  those  previously  mentioned  as  occurring  in  the  vicinity 
of  Kylemore,  south  and  south-west  of  Bcngooria,  also  many  in  the 
country  to  the  eastward  of  Clifden.  These  may  be  of  Silurian  age,  as 
they  graduate  into  eurytes  identical  with  the  eurytes  interstratificd  with 
the  rocks  of  Upper  Llandovery  age.  If  this  surmise  is  correct,  we  have 
data  on  which  to  calculate  the  depth  beneath  the  earth's  surface  at 
which  a  felstone  or  other  plutonic  rock  will  graduate  into  an  elvanyte. 
The  mass  of  euryte  at  Benchoona  is  about  2000  feet  above  the  base  of 
the  Silurian  rocks ;  but  if  we  suppose  a  thickness  of  the  metamorphic 
rocks  equal  to  half  of  this  was  denuded  away  in  the  neighbourhood  of 
Ballyn^iinch  lake  and  Clifden,  where  these  rocks  are  so  numerous, 
these  would  be  a  total  thickness  of  3000  feet.  There  is,  however, 
another  locality  in  Ireland,  namely,  the  county  Limerick,  where  an 
estimate  also  can  be  made.  In  that  countv  there  are  bedded 
dolerytes,  melaphyres  and  eurytes  in  the  carboniferous  rocks,  at  the 
junction  of  the  lower  and  middle  limestone,  and  at  the  junction  of 
the  limestone  and  the  coal  measures;  while  in  lower  rocks,  near 
the  base  of  the  carboniferous  limestone,  are  pipes  or  protrusions  of 
basic  elvanyte,  evidently  the  roots  of  some  of  the  rocks  that  at 
higher  zones  were  irrupted  among  and  bedded  with  the  derivated  rocks. 
Between  the  rocks  where  these  roots  occur  and  the  junction  of  the 
lower  and  middle  limestone  there  is  a  thickness  of  about  1000  feet» 
and  to  the  base  of  the  coal  measure  of  about  2300  feet.  If,  therefore, 
these  roots  belong  to  the  igneous  rocks  of  the  lower  zone,  elvanyte 
may  form  at  a  depth  of  about  1000  feet,  while  if  to  the  upper,  at  a 
depth  of  2300  feet. 

It  was  previously  stated,  that  between  the  intrusive  oligoclasic 
granite  and  the  metamorphic  sedimentary  rocks  intrusions  of  the 
orthoclasic  granite  were  not  uncommon.  This,  if  the  above  sugges- 
tions are  correct,  might  naturally  be  looked  for.  For  as  the  mass  of  the 
oligoclasic-granite  cooled,  it  would  shrink  from  the  adjoining  rocks, 
thereby  causing  vacancies  into  which  the  non-consolidated  orthoclasic 
granite  should  be  intruded,  and  also  inte  all  the  cracks  and  fissures  in 
the  associated  gneiss  and  schist  formed  during  their  cooling,  they 
necessarily  having  been  heated  and  expanded  while  in  contact  with 
the  oligoclasic  granite. 

It  seems  to  be  a  very  generally-received  opinion  that  all  granites 
metamorphosed  the  rocks  with  which  they  come  in  contact ;  to  me, 


KiNAHAN — Oh  Granitic  and  other  Ingenite  Bocks.        137 

however,  it  appears  that  granite  is  the  result  of  metamorphism,  and  not 
metamorphism  of  granite,  and  that  the  rocks  associated  with  granite 
formed  in  situ  must  he  metamorphosed ;  hut  that  rocks,  even  in  con- 
tact with  intrusive  granite,  may  only  he  slightly  altered,  not  more  so 
than  often  happens  to  rocks  in  contact  with  large  dykes  or  masses 
of  plutonic  rocks.* 

In  the  islands  north  of  the  mouth  of  Galway  Bay  (Gorumna  and 
Lcttcrmullan),  the  rocks  are  very  little  altered,  yet  they  are  adioining 
or  in  close  proximity  to  a  largo  tract  of  intrusive  granite.  North  of 
Killary  Harhour,  the  rocks  forming  the  hills  north  of  Doolough  are 
scarcely  changed,  so  that  if  met  with  in  any  other  locality  the  itera- 
tion would  he  passed  over  iinnoticed ;  yet  immediately  to  the  north  of 
them  is  a  large  tract  of  intrusive  granite,  while  in  the  neighhourhood 
of  the  Oughterard  tract  of  granite,  the  sedimentary  rocks  are  less 
altered  than  in  many  other  places  in  West  Galway.  Here  limestone  is 
found  in  contact  with  the  granite,  and  often  caught  up  in  it,  yet  the 
limestone  is  not  much  changed ;  that  caught  up  in  it,  or  in  immediate 
contact,  has  lost  all  its  colour  and  hecome  highly  crystalline;  hut 
these  changes  only  exist  for  a  few  }ards,  as  limestone  not  200  feet 
from  it  was  found  to  he  scarcely  altered,  compared  with  other  places 
in  the  district.  On  the  other  hand,  an  ohserver  can  always  know 
when  he  is  approaching  granite  formed  in  situ,  hy  the  remarkahle 
changes  that  take  place  not  only  in  the  aspect,  hut  also  in  the  structure 
of  the  rocks.f 


*  In  the  country  north  of  Killary  Harbour  there  are  shales  adjoining  dykes  of 
felstone  altered  into  homstone.  At  Curraghrevagh,  on  Lough  Corrib,  there  are  Silu- 
rian rocks  micacised  and  indurated  by  a  protrusion  of  diabase,  and  in  many  other 
places  in  Ireland  similar  alterations  could  be  pointed  out;  the  rocks  in  each  case  being 
more  metamorphosed  than  any  of  the  rocks  that  I  saw  associated  with,  or  even  in 
contact  with,  tne  Dartmoor  granite,  Devonshire.  From  the  circumstances  associated, 
when  derivate  rocks  in  contact  with  plutonic  rocks  are  altered,  I  am  incUncd  to 
believe  such  alterations  are  not  due  to  the  plutonic  rocks,  but  to  heat,  either  wet  or 
dry,  that  came  up  in  the  divisional  plane  or  Uie  fissure  between  the  different  classes  of 
rocks. 

t  In  some  places,  as  for  instance  ELUiney,  the  rocks  in  contact  with  the  mass  of  in- 
trusive granite  of  Dublin,  Wicklow,  Carlow,  and  Kildare,  are  much  altered ;  but  in 
other  places,  such  as  the  neighbourhood  of  Castlcdermot,  Co.  Kildare,  they  are  not. 
To  account  for  this,  I  would  suggest  that  some  of  the  intrusive  masses  of  granite 
cooled  under  such  circumstances  that  the  heat  from  them  had  to  x>orcolate  the 
associated  rocks,  while  in  such  masses  as  that  at  Dartmoor,  Devonshire,  where  the 
rocks  in  contact  are  scarcelv  changed,  the  rock  must  have  cooled  imder  such 
circumstances  that  the  heat  all  escaped  without  affecting  the  associated  rocks.  This 
pent-up  heat,  if  it  escaped  along  the  walls  of  a  plutonic  or  volcanic  dyke,  would  more 
or  less  alter  the  rocks  it  passed.  Every  fresh  locality  for  granite  that  I  visit,  the 
more  I  am  convinced  that  granite  is  the  result,  not  the  cause  of  metamorphism.  Since 
this  essay  was  read  I  have  more  carefully  examined  the  rocks  in  the  vicinity  of  the 
granite  exposure  north  of  Doolough,  coimty  Mayo,  and  find  some  of  the  rocks  so 
tittle  altered  that  their  fossils  are  quite  perfect ;  while  at  the  extreme  S.  E.  end  of 
the  county  Wexford  there  is  granite  due  to  metamorphism  that  graduates  through 
gneiss  into  schists,  while  to  the  N.  E.  of  the  same  county,  and  in  the  county 
wicklow,  the  rocks  in  juxtaposition  with  tiie  intnisive  granite  are  lees  altered 


138  Proceedings  of  the  Royal  Irkh  Academy, 

If  the  BUggestioiis  that  we  have  been  considering  are  coirect,  the 
granite  that  ^t  cooled  ought  always  to  be  less  BHiceous  than  the 
granite  intruded  into  it ;  while  the  veins  of  segregation  or  cooling 
(ffranityte)  ought  to  be  more  siliceous  than  the  rock  in  which  they 
appear,  and  from  which  they  separated ;  and  this  seems  to  be  always 
the  case  in  West  Galway.* 

than  those  farther  away.  In  the  north  of  Ireland,  at  the  Moume  intmuye  granite 
district,  county  Down,  the  rocks  next  the  granite  are  only  veij  slightly  altered,  and 
appat^nUy  this  metamoiphism  is  much  older  than  the  intrusion  of  these  poet-car- 
boniferous granites ;  while  in  the  Carlinsford  district,  county  Louth,  the  carbonif e- 
rouB  rocks  limestone),  through  which  a  laxve  mass  of  granitoid  elvanyte  protrudes, 
aro  apparently  uncluuiged.  To  the  north  of  these  districts  the  older  intrusive 
granite  of  Newry  and  Slieve  Croob,  as  proved  by  my  colleague,  W.  A.  Trail, 
F.R.G.8.I.,  has  alongside  in  places  rocks  more  metamorphosed  than  is  general  in  the 
county  Down,  but  this  alteration  is  always  very  small,  and  does  not  appear  to  be 
general  round  the  mass.  It  is  also  so  slight,  that  all  the  metamorphic  rocks  in  the 
vicinity  of  the  Newry  and  Slieve  Croob  granite  belong  to  the  class  called  **  Sub- 
motamorphic  rocks"  by  the  officers  of  the  Indian  Geological  Survey.  Trail  has  also 
pointed  out  that  in  Uiose  places  where  the  derivate  rocks  are  thus  additionally 
altered,  the  adjoining  granite  is  foliated ;  as  if  subsequent  to  the  intrusion 
of  the  granite  a  strip  of  country  had  been  invaded  by  heat  (wet  or  dry), 
which  hid  developed  a  foliation  in  the  granite,  and  slip^htly  increased  the  meta- 
morphism  ci  the  adjoining  derivate  rocks  ;  and  this,  he  thinks,  seems  to  be  suggested 
by  uie  action  decreasing  both  ways  as  we  leave  the  jimction  of  the  granite  and  the 
schist,  at  which  line,  naturally,  the  heat  might  be  expected  to  be  most  intense. 
[Xote  added  in  the  preuJ] 

*  This  remark  can  only  refer  to  a  syistem  of  granites  formed  at  one  time ;  for  if 
one  system  of  granites  were  formed  in  the  suurian  period,  and  another  in  the 
carboniferous  period,  the  basic  granites  belonginj^  to  the  latter  might  occur  breaking 
up  through  the  highly-siliceous  granites  belonging  to  the  former.  Two  quite  diffe- 
rent classes  cf  veins  are  known  as  "  veins  of  segregation ; "  one  kind,  which  is 
always  more  or  less  regular,  is  due  to  a  portion  of  the  fluid  rock  segregating  from 
the  rest,  and  filling  the  shrinkage  fissures  and  such  like  vacancies;  to  such  veins  the 
above  remark  appUes.  The  omer  class  is  always  most  irregular,  often  lenticular, 
and  appears  to  be  due  to  minerals  in  solution,  which  subsequently  crystallized, 
filling  irregular  vugs  or  cavities  in  the  rock  mass ;  to  such  veins  belongs  the  rock 
previously  described  under  the  name  of  pegmatyte.  Hunt,  as  previously  mentioned, 
has  suggested  the  name  of  endogenous  for  these  vein-rocks  or  "  granite  vein-stones," 
to  «^iB^TlgnMff^l  them  from  true  granitic-dykes. — "  Report,  Geol.  Surv.  of  Canada,*' 
p.  192. 


Macalister — On  Cranial  OsteoloQy  of  Sloths,  139 


XVIII. — On  a  Few  Points  in  thb  Cbaioal  Osteoloot  op  Sloths. 
By  Alex.  Macalisteb,  M.B.,  Professor  of  ComparatiYe  Anatomy, 
Dublin  University.     (With  Plate  13.) 

[Bead  January  25, 1875.] 

Iv  the  Mnsenm  of  the  University  of  Dublin  there  are  several  very 
good  specimens  of  Sloths,  some  of  which  were  brought  home  from 
South  America  by  the  Bev.  J.  McGregor  Ward,  lately  Chaplain  to 
H.  M.  S.  Egmont,  and  some  by  Dr.  Newton.  In  one  of  these,  a  very 
young  specimen  of  Bradypw  gtdarisy  measuring  only  10  inches  in 
length  of  body,  the  skull  exhibits  several  curious  points. 

1st.  A  vertical  medial  supra-occipital  suture,  extending  from  the 
middle  of  the  back  of  the  foramen  magnum  to  the  back  of  the  sagittal 
suture.  Then  the  supra-occipital  consists  of  two  lateral  symmetrical 
pieces. 

2nd.  There  are  three  wormian  bones,  two  to  the  right,  and  one  to 
the  left  of  the  median  line  in  the  place  of  the  interparietal  bone. 

3rd.  The  post  premaxillary  tooth  (Cauiniform  molar  of  CholoBpus) 
is  very  sharp-pointed,  directed  backwards  and  inwards. 

4tih.  Owing  to  the  absence  of  the  frontal  sinus  (which  in  the  adult 
J9.  torquatus  occupies  the  whole  of  the  frontal  bone),  the  skull  narrows 
from  the  parietal  eminences  forward.  There  are  two  slight  fissures, 
one  on  each  side  of  the  middle  of  the  frontal  suture. 

5th.  The  pterygoids  have  even  so  early  a  trace  of  the  "Arcto- 
pithecus"  thickening.  The  weak  intermaxillaries  are  very  faintly 
discernible,  with  a  slight  bony  nucleus.  In  the  accompanying  Plate, 
figure  1  shows  the  back  of  the  skull  with  the  vertical  occipital  sutm-e. 
figures  2  and  4  show  the  peri-orbital  bones,  and  the  relation  of  the 
lachrymal  to  the  malar.  Figure  3  shows  the  group  of  wormian  bones. 
Figure  5  shows  the  solid  stapes  resembling  the  columella  of  birds, 
characteristic  of  the  sloths. 


140  Proceedings  of  the  Royal  Irinh  Academy. 


XIX. On    CHXAMTDOaCTIA    LABJBnrrHrLOIDES,     NOV.     OEW.    ET    sp.,    A 

New   Freshwater    Sarcodic   ORGAinsx.     By  William    Archer, 
M.  R.  I.  A.     (With  Plates  1 4  and  1 5. ) 

[Read  Febnmiy  22,  1876.] 

Some  short  time  after  the  appearance  of  Cienkowski's  memoir  on  a 
new  type  of  Sarcodic  existences,  met  with  by  him  in  the  sea  (at 
Odessa),  which  he  named  Labyrinthuleae,  I  was  not  a  little  surprised 
and  interested  on  meeting  with  a  form  from  the  freshwater  so  wonder- 
fully resembling  those  described  by  him,  as,  notwithstanding  one 
circumstance,  hereafter  to  be  adverted  to,  even  still  to  render  it  a 
matter  of  considerable  question  whether  it  may  not  truly  belong  to 
that  group,  even  though  it  should  not  be  congeneric  with  the  typical 
Labyrinthula  ( Cienko wski) .♦ 

I  regret  indeed  that,  after  repeated  eflForts  to  learn  more  of  its 
development  or  history,  I  have  but  little  succeeded,  except  so  far  as 
knowing  that  it  is  an  endoparasitic  growth,  at  least  for  a  portion  of  its 
existence. 

It  will,  perhaps,  be  the  best  course  to  endeavour  first  to  give  an 
idea  of  this  curious  production  as  it  exists,  before  referring  to 
Cienkowski's  forms,  which  would,  indeed,  be  necessary  previous  to 
comparing  or  contrasting  it  therewith,  or  with  any  other  simple 
organisms  evincing  any  similarity  in  minute  specialities. 

The  component  elements  of  the  present  form,  broadly  taken,  are 
primarily  divisible  into  two — the  inner  soft  sarcodic  body-substance,  or 
contents,  and  the  outer  rigid  cyst,  or  envelope,  which  nearly  constantly 
surrounds  the  former. 

But  neither  of  these  is  quite  simple,  especially  the  latter,  which 
presents  a  variety  of  constituents. 

To  advert  briefly  in  the  first  place  to  the  lattey,  the  outer  coat  or 
envelope,  its  complexity  consists,  indeed,  only  in  the  number  of  similar 
layers  of  which  it  is  composed,  and  its  great  irregularity  of  outline. 
It  is  often  very  thick,  according  to  the  number  of  laminsB  of  which  it 
is  made  up,  but  even  the  thinnest,  or  such  as  possess  but  a  single  lamina, 
would,  on  the  whole,  be  called  "thick- walled"  as  compared  with  many 
vegetable  cells.  This  wall  is  hyaline,  and  when  viewed  superficially  it 
is  colourless,  or  nearly  so,  but  when  viewed  edgeways  or  at  the  margin 
of  a  many-laminated  example,  where  a  considerable  density  is  therefore 
seen  through,  it  appears  of  a  pale  straw  colour  or  brassy  hue,  and  ex- 
tremely shmy  and  glossy.     Its  consiBtence  is  tough,  requiring  strong 

*  Cienkowaki :  "  Ueber  den  Bau  und  die  Entwickelung  der  Labyrinthuleen," 
in  Schultze's  "  Arehiv  fiir  mikr.  Anatomie,"  Bd.  iii.,  p.  274. 


Archer — On  Chlamydomyxa  Labyrinthuloide^.  141 

pressure  on  the  covering-glass  to  burst  it  (Plate  15,  fig.  4).  As  men- 
tioned, its  outline  is  most  varied ;  globose  or  broadly  oval  might,  per- 
haps, be  called  the  typical  form,  but  examples  lobed  in  a  variety  of 
ways  are  extremely  frequent.  Nearly  always,  from  one,  two,  or  more 
places,  are  given  off  neck-like  extensions,  of  greater  or  less  width, 
terminating  in  a  lacerated  manner ;  these  are  produced,  as  it  were,  by 
the  prolongations  laterally  of  a  certain  number,  greater  or  less,  of  the 
laminae  composing  the  wall,  and  then  as  if  abruptly  torn  off.  (Plate 
14;  Plate  15,  figs.' 3,  4,  5.) 

Leaving  the  outer  envelope  for  the  present,  and  passing  to  the 
inner  soft  and  plastic  *' living''  portion,  this  is  not  a  simple  or  homo- 
geneous plasma  or  sarcode,  but  is  itself  composed  of  scvcnil  seemingly 
distinct  elements.  The  first  of  these  is  the  basic  substance  of  hyaline 
character,  fonning  the  common  connecting  medium  of  every  other 
element  (except,  of  course,  the  outer  cyst  or  envelope  alluded  to)  when 
the  organism  is  in  what  may  be  called  its  state  of  repose — a  state  in 
which  seemingly  by  far  the  greatest  portion  of  its  existence  is  passed. 
But  at  times  a  far  more  striking  and  remarkable  phase  presents  itself, 
when  further  structural  elements  of  the  ''living"  portion  or  contents 
come  to  view,  and  to  which  I  shall  advert  in  the  order  in  which  they 
would  most  probably  attract  the  attention  of  an  observer  examining  an 
example  of  this  production  in  **  good  order"  for  the  first  time. 

Since  I  met  with  this  organism,  on  the  first  occasion  in  a  single 
pool  in  the  Co.  Westmeath,  I  have  found  it  in  several  not  very  distant 
sites  in  Connemara,  having  since  then  learned  to  detect  its  presence  in 
quantity  by  the  reddish  colour  presented  to  the  eye  in  the  mass  when 
it  is  in  the  dormant  or  encysted  condition,  so  abundant  does  it  even- 
tually become  in  pools  where  it  occurs.  Upon  the  earlier  occasions  of 
taking  it,  indeed,  the  red  colour  was  by  no  means  so  prominent  a 
characteristic  as  it  seemed  to  have  rendered  itself  subsequently,  but  it 
was  still  a  sufficiently  striking  feature. 

In  examples  (especially  as  more  lately  taken)  it  is  just  this  reddish 
colour  which  would  likewise  first  attract  notice  under  the  microscope. 
This  is  due  to  a  number  of  granules  of  varying  magnitude,  often  rather 
large,  but  mostly  very  minute,  with  a  dark  outline  and  of  a  bright  red 
colour.  (Plate  14,  fig.  2,  to  the  right ;  fig.  4.)  These  may  be  often 
present  in  some  examples  in  great  abundance,  sometimes  in  others 
more  sparse,  sometimes  very  few,  or  they  may  be  in  some  specimens 
all  but  or  quite  absent. 

Of  the  granular  or  solid  contents,  besides  the  red  granules,  others  of 
a  vellowish-green  colour  will  attract  attention.  These  are  usu^ly  more 
mmute  than  the  larger  of  the  red  granules,  but  ordinarily  surpass  them 
in  quantity,  the  red  ones  only  rendering  themselves  more  conspicuous 
at  first  and  in  the  mass  by  their  brighter  and  therefore  more  striking 
colour.  The  fewer  the  red  granules  the  more  abundant  the  green,  and 
vice  versd.  These  green  granules  resemble  much  the  chlorophyll- 
granules  of  certain  algee,  though  they  are  never  of  a  grass-green,  but 
are  always  of  a  yellowish  hue.     I  suppose  it  to  be  very  probable  that 

R.  1.  A.  PBGC,  SBR.  II.,  VOL.  II.,  SCIENCE.  V 


142  Proceedings  of  the  Royal  Irkh  Academy. 

the  red  granules  are  in  reality  produced  by  change  of  colour  of  the 
green.     (Plate  14 ;  Plate  15,  fig.  2  to  the  left;  fig.  4.) 

But  in  the  formation  of  the  **  contents"  yet  another  granular  con- 
stituent has  a  part.  Besideewthe  above-mentioned  red  and  yellowish- 
green  granules,  minute  homogeneous-looking  rounded  little  granules 
voccur,  of  a  pale  bluish  tint.     (Plate  14.) 

When  wholly  encysted,  and  now  in  a  completely  dormant  and 
-quiescent  condition,  the  organism  appears  very  densely  filled,  and 
Jience  the  larger  examples  are  quite  opaque. 

The  first  and  second  year  of  my  noticing  this  organism,  in  ex- 
:amples  from  the  Co.  Westmeath  pool,  quite  frequently — since  then 
from  that  site,  as  well  as  Connemara,  very  rarely— did  I  succeed  in 
obtaining  a  view  of  the  condition  now  to  be  described.  It  was  there- 
iore  well  to  have  secured  the  accompanying  drawing,  when  the  ex- 
amples were  readily  found  in  suitable  order. 

IS^otwithstanding  the  seemingly  tough  consistence  of  the  wall,  or 
envelope,  in  manipulation,  the  contents  have  the  power  to  burst  or 
force  tiieir  way  outwards  through  it,  and  the  basic  plasma  pours  itself 
forth,  bearing  with  it  the  granular  contents  as  described,  but  not  any 
of  these  escape  or  become  scattered,  for  they  are  held  together  by  the 
common  medium,  but,  on  the  contrary,  they  pass  onwards  with  it,  and 
soon  a  remarkable  sight  presents  itself,  llie  plasma,  thus  become  ex- 
tended and  spread  out  over  a  space  so  much'  greater  than  when  it 
occupied  the  cavity  of  the  envelope,  now  shows  the  contained  granules 
mutually  much  fiuther  apart,  rendering  the  hyaline  connecting  basic 
medium  in  itself  more  apparent.  This  does  not  seem  to  form  a  border, 
or  any  "ectosarc"  region;  the  contained  granules  stand  close  up  to 
the  outer  contour,  leaving  no  hyaline  margin.  In  examples  presenting 
this  condition  in  a  well-expressed  manner  (Plate  14),  I  think  I  see 
yet  another  constituent  of  the  basic  substance,  different  from  the  com- 
mon hyaline  matrix — ^a  kind  of  greenish,  plastic,  amorphous  substance, 
88  it  were  comparable  to  "  diffused"  chlorophyll,  seemingly  distinct 
from  and  yet,  as  it  were,  combining  at  the  margins  (if  one  may  use  the 
word)  of  tiie  patches  of  it,  with  the  hyaline  matrix,  than  which,  how- 
ever, this  substance  appears  to  be  of  a  less  fluent  or  yielding  nature. 
I  do  not  think  it  would  be  capable  of  detection  unless  in  examples  so, 
as  one  might  say,  "  on  the  stretch."  Now,  a  beautiful  play  of  quite 
globular  puUating  vacmleB  is  seen  to  take  place  in  the  basic  mass ; 
these  vacuoles,  though  very  numerous,  never  become  very  largely  dis- 
tended. It  is  very  interesting  to  watch  their  alternate  diastole  and 
systole,  now  here,  now  there,  distributed  all  over  the  extended  mass ; 
but,  to  see  this  properly,  attention  should  be  confined  to  a  single 
vacuole.  It  is  curious  to  observe  a  vacuole  originate  in  the  middle  of 
a  layer  of  the  greenish  substance  adverted  to-^the  vacuole  expands  for 
a  time  in  the  usual  manner,  but,  as  if  the  expansion  took  place  too 
vigorously  in  proportion  to  the  yielding  capacity  of  the  surrounding 
substance,  the  latter  becomes  somewhat  suddenly,  as  it  were,  cracked 
or  9pUt  at  opposite  sides  of  the  globular  vacuole,  the  rift  extending  to 


Archer — On  Chlamydofnyxa  LabyrinthuUndea,  143 

a  length,  perhaps,  as  great  as  the  diameter  of  the  vacuole ;  anon  the 
contraction  abruptly  sets  in,  and  the  divided  surrounding  substance  re- 
unites^ and  the  rift  becomes  obliterated  (as  it  were  re-fused),  perhaps 
not  to  return,  rven  should  the  vacuole  reappear  in  the  same  place. 
(Plate  14.  See  the  vacuole  in  centre  of  the  subtriangnlar  outlying 
portion  of  plasma  to  the  left.) 

But,  as  we  watch,  attention  will  soon  be  drawn  off  from  the 
vacuoles.  The  first  issuing  portion  of  contents,  upon  being  some  time 
advanced  into  the  surrounding  water,  forms,  as  it  were,  a  primary 
tronk,  which  soon  subdivides  into  a  number  of  branches  which  taper 
off,  or  after  tapering  a  little  may  again  become  expanded,  forming  a 
<< peniiilsula"  of  the  extended  body-substance;  or  the  connectmg 
"isthmus"  may  disappear,  leaving  an  ''island"  formed  of  the  sarcode- 
substance  lying  apart.  Presently,  issuing  from  various  parts  of  the 
''trunk"  and  principal  "branches,"  as  we  have  seen  abounding  in 
vacuoles,  are  soon  noticed  ramifications,  extending  far  and  wide  in  the 
most  complex  manner,  offiliformy  hyaline^  quite  eohurleee  threads  of  ex- 
iraordinary  tenuity.  These  extremely  delicate  processes  are  flexible, 
but  do  not  seem  spontaneously  to  alter  much  in  position  as  first  de- 
veloped, or  at  least  very  slowly,  but  only  to  grow  in  length  and  num- 
ber. But,  further,  pari  passu  with  their  own  appearance,  occur  at 
various  distances  upon  them  minute  fusiform  bodies  of  a  pale  bluish  tint, 
their  longitudinal  axis  posed  in  the  du*ection  of  the  length  of  the  filament. 
At  first  glance  these  might  momentarily  be  taken  for  so  many  fusi- 
form expansions  or  enlargements  of  the  delicate  filament  itself,  offer- 
ing a  degree  of  (bluish)  colour,  owing  merely  to  their  greater  thickness. 
But  a  closer  inspection  at  once  dispels  this  idea :  the  fusiform  bodies 
are  seen  to  be  in  motion,  though  slow,  along  the  hair-like  filaments.  (PL 
14,  passim,) 

A  very  few  minutes'  examination  suffices  to  prove  this.  I  regret 
I  have  not  a  note  of  their  rate  of  progression ;  but  if  attention  be  be- 
stowed on  any  few  spindles  (four,  five,  or  six),  at  any  given  place  on 
one  of  these  capillary  filaments,  their  relative  distances  will  be  noticed 
to  have  considerably  altered  in  a  few  minutes.  The  little  spindle,  now 
in  advance  of  several  others,  may  slacken  its  pace  as  compared  with 
those  behind,  or,  what  comes  to  the  same  thing,  the  hindermost  may 
become  accelerated ;  the  natural  result  is  that  the  foremost  spindle  is 
overtaken  ;  it  may  then  act  as  a  temporary  stop  or  barrier  to  the  ad- 
vance of  those  behind,  and  the  little  group  may  come  to  a  standstill. 
They  may  then  remain  in  linear  sequence,  or  become,  as  it  were,  hud- 
dled together,  and  form  a  little  cluster,  but  by-and-by  they  may  resume 
their  movement.  But  in  such  a  case  of  a  spindle  now  in  advance  be- 
coming checked,  what  is  more  singular  may  sometimes  happen — ^the 
hindermost  may  actually  creep  over  the  kay  one  in  front,  and,  this 
accomplished,  then,  nothing  baulked,  quietly  pursue  its  way,  leaving 
the  spindle  previously  in  advance  of  it  far  behind. 

It  is  natural  to  speak  of  these  minute  travelling  bodies  as  spindles, 
for  that  is  their  usual  shape,  but  this  can  vary.     In  such  a  curious 


144  ProceedingH  of  the  Royal  Irish  Academy. 

case  OB  that  just  mentioned^  of  one  of  these  bodies  passing  right  over 
another  in  advance  ci  it,  sooner  than  allow  it  to  remain  a  barrier  to  its 
progress,  the  former  may  assume  a  rounded  or  even  a  globose  figure 
during  the  accomplishment  of  the  act.  (Its  sluggish  motion,  and  its 
often  somewhat  alug-ltke  figure,  as  it  slowly  passes  up  and  over  its  pre- 
decessor, seemingly  at  a  standstill,  might  fancifully  suggest  a  pair  of 
alugSy  unable  to  do  more  than  creep,  making  an  effort  to  accomplish 
between  them  but  at  best  a  very  tardy  game  of  ** leap-frog!")  But 
when  the  little  travelling  body  has  passed  over  the  other,  the  fusiform 
figure  is  resumed.  But  normally,  during  progression,  these  bodies 
may  sometimes  represent  rather  a  semi-fusiform  figure,  that  is,  one 
side  may  be  rectilinear,  this  latter,  when  presented,  being  the  side 
applied  to  the  capillary  filament  upon  which  it  travels,  and  the  con- 
vex side  raised  up  therefrom.  During  progression  a  still  greater 
alteration  of  figure  from  the  onlinary  fu»f orm  may  present  itself  when 
one  of  these  bodies  arrives  at  a  fork  of  the  filament ;  then,  as  if  it  were 
uncertain  as  to  which  route  it  ought  to  take,  it  becomes  itself  bifur- 
cated, and  one  log  follows  one  branch  of  the  filament,  the  other  leg 
the  other  branch,  and  so  the  little  body, -now  triradiate,  may  for  some 
time  remain  stationary,  as  it  were,  astride  upon  the  bifurcation. 

These  little  eminently  plastic  bodies  (one  might  roughly  compare 
one  to  a  piece  of  glazieT^B  putty,  or  to  dough)  are,  in  fact,  identical  with 
the  little  rounded  or  globular  bluish  homogeneotts-looking  little  granules 
in  the  centred  mass  to  which  attention  was  at  first  directed,  and  which 
are  distinctly  fusiform  only  when  upon  the  capillary  filaments,  although, 
indeed,  before  they  arrive  there  they  may,  some  of  them,  appear 
elliptic  or  subfusiform.  That  they  are  really  one  and  the  same  thing, 
notwithstanding  the  difference  of  figure  between  them  as  a  rule,  is  seen 
by  watching  the  rounded  granules  deliberately  proceed  out  of  the 
general  central  mass  and  pass  up  along  one  of  the  filaments ;  as  soon 
as  it  has  done  so  and  begins  to  travel  upwards,  the  globose  figure  is 
lost  and  the  fusiform  outline  is  assumed.  Boon  follows  another  and 
another,  in  just  the  same  manner,  and  a  more  or  less  long  cortige  be- 
gins its  curious  procession.  By-and-by  some  of  the  little  bodies  may 
retrograde,  remain  stationary,  or  again  advance,  or  all  may  become 
drawn  in,  capillary  filaments  and  all,  and  the  whole  become  reabsorbed 
into  the  great  central  mass.  When  one  of  the  little  spindles  returns 
from  its  journey  it  passes  down  from  off  the  capillary  support  and  reas- 
sumes  a  globose  figure,  and  joins  the  rest  of  the  similar  granules  within 
the  central  mass. 

It  is  when  a  great  ramified  tree  is  thus  formed,  under  the  observer's 
eye,  perhaps  in  ten  or  twenty  minutes,  and  numerous  capillary  fila- 
ments spread  in  every  direction,  up  and  down  and  laterally  and  round 
about,  these  well  laden  with  spindles  and  the  central  mass  thus  thinned 
out  and  wide  spread  and  relieved  of  so  great  a  proportion  of  the  gra- 
nular contents,  that  the  beautiful  play  of  vacuoles  referred  to  can  be 
seen,  and  the  whole  object  presents  a  spectacle,  in  its  way,  of  unusual 
and  exceeding  beauty.    (PI.  14.)     It  must  be  borne  in  mind  that  the 


Archer — On  Chlamydomyxa  Lahyrinthuloides,  145 

example  figured,  amply  furnished  with  ramifications^  and  with  a  tortuous 
''  labyrinth"  of  filaments,  as  it  is,  and  well  laden  with  spindles,  as  it 
appears,  after  all  merely  represents  what  could  be  seen  in  a  single 
foetU  plane,  whilst,  perhaps,  ramifications  sufficient  to  make  up  several 
such  complex  ''  trees"  occur  in  difPerent  planes  between  the  slide  and 
the  covering-glass,  and  which  can  be  made  out  by  focusing  up  and 
down,  all  appertaining  to  the  single  main  trunk,  and  derived  in  a 
brief  period  from  the  great  common  central  head-quarters ;  nay,  some- 
times a  secondary  eohny  may  be  carried  outwards  and  left  apart  at 
some  remote  point  of  the  field,  this  latter  now  itself  giving  off  minor 
branches  and  filaments  back  towards  the  metropolis,  (See  the  more 
distant  portion  of  PI.  14.) 

We  have  seen  that  these  little  bodies  are  of  a  homogeneous  consist- 
ence, of  a  highly  plastic  nature,  and  of  a  bluish  hue ;  they  further 
appear  to  have  no  wall  or  envelope,  that  can  be  detected ;  still  they  do 
not  mutuallv  coalesce,  and,  however  intimately  they  may  be  temporarily 
applied,  a  close  examination  will  show  their  individual  contours.  I 
have  not  been  able  to  see  any  subdivision  of  them.  Their  motion  is  a 
gliding  one,  and,  as  has  been  seen,  it  is  always  very  gradual  and  easy, 
though  sometimes  slower,  sometimes  quicker,  without  any  apparent 
rule  or  reason.  Just  as  little  rule  or  reason  is  evident  in  the  course 
taken  by  the  individuals,  now  of  one  and  the  same  file — one  may  go 
the  "  main  road,"  the  other  following  it  may  take  a  **  byway."  Some 
reason,  so  far  as  it  goes,  appears  why  some  should  travel  up  the  fila- 
ments and  others  remain  behind  in  the  general  mass,  in  that  it  is  seem- 
ingly just  those  which  are  most  external,  therefore  nearest  the  place 
of  origin,  that  is  the  base,  of  the  filaments,  which  betake  themselves 
thereon  for  the  journey. 

But  if  the  variable  rate  and  direction  of  the  movement  of  these 
bodies  be  inexplicable,  even  still  more  enigmatical  appears  the  cause, 
or  the  modus  operandi,  of  the  motion  itself.  t)ne  might  suppose, 
indeed,  that,  once  upon  the  filament,  its  elongation  would  cause  the 
separation  of  the  bodies  and  give  rise  merely  to  a  seeming  progression 
one  from  another.  But  we  have  seen  their  motion  is  a  real  one,  and, 
in&u^t,  automatic.  They  "spontaneously"  leave  the  general  mass, 
and,  ascending  the  filament,  commence  their  onward  progress,  and 
the  latter,  when  once  projected,  seems  to  be  even  somewhat  rigid,  and 
incapable  of  imparting  to  them  any  impetus.  The  cause  of  the  motion 
would  seem,  therefore,  to  reside  in  the  spindles  themselves :  they  are 
very  plastic — ^they  must  seemingly  be  very  contractile.  But  as  they 
gently  and  smoothly  glide  onwards,  as  \1  without  effort,  and  free  from 
interruption,  no  very  perceptible  change  of  figure  from  the  spindle- 
form  is  usually  seen,  except  the  flat  form  occasionally,  or  the  furcate 
form  more  rarely,  as  before  adverted  to.  In  the  case  of  two  flattened 
spindles,  they  may  sometimes  be  seen  gliding  at  opposite  sides  of  the 
filament,  and  one  may  pass  the  other  with  the  filament  between,  and 
now  without  any  change  of  figure,  unlike  what  occurs  when  two  or 
several  meet  at  the  same  side  and  cluster  together. ' 


146  Proceedings  of  the  Royal  Irish  Academy, 

Not  less  curious  is  it  again,  seemingly,  how  these  little  bodies 
remain  upon  the  filament.  What  power  keeps  them  there  ?  They  never 
seem  to  glide  off  or  to  be  met  with  in  the  water  around.  In  fact, 
these  little  performers  on  the  "  slack  rope"  seem  to  hold  on  admirably 
— but  then  their  action  is  very  deliberate ! 

I  have  sometimes  supposed  that,  surrounding  both  spindles  and 
filaments,  a  very  subtle  and  delicate  sheath,  or  envelope,  must  exist, 
of  some  amount  of  c'>ntractile  power,  whose  action  might  exercise  a 
propelling  force  to  urge  the  spindles  along  the  median  axis,  or,  at 
least,  to  act  as  an  auxiliary  in  conjunction  with  their  inherent  con- 
tractile locomotive  power.  Under  a  very  high  amplification  indeed,  I 
have  thought  to  have  seen  such  a  delicate  envelope,  but  I  cannot  say 
that  the  appearance  might  not  have  been  due  to  an  optical  illusion. 

However,  such  a  structure  would  not  be  without  parallel  in  certain 
Helizoan  Ehizopoda,  for  instance,  Actinosph^trium  Eichhomiiy  in 
which  the  radiating  pseudopodia  possess  a  central  axis  of  firmer  con- 
sistence (surely  not  comparable  to  a  spicule),  covered  by  a  softer 
sarcode  envelope,  certain  granules  passing  between,  evidently  carried 
passively  by  the  latter.  But  the  movement  of  the  spindles,  consisting, 
as  it  does,  of  a  quiet  and  smooth  glide,  is  of  different  character..  The 
axis  of  the  pscudopodium  of  Actinosphasrium,  comparatively  speaking, 
is  a  much  coarser  object  than  the  delicate  filament  upon  which  the 
spindles  travel  in  the  present  organism,  and  the  soft  involving  gra- 
nidar  sarcode  of  the  former  is  indeed  a  very  palpable  thing  as  com- 
pared with  the  very  subtle  sheath  assumed  to  possibly  exist  in  the 
latter. 

There  exists  a  certain  minute  rhizopod,  of  which  I  have  seen  but 
very  few  examples,  and  have  therefore  had  by  far  too  restricted 
opportunity  to  study  it,  to  give  an  account  of  or  to  describe  it.  It  is 
therSj  however,  and  even,  as  is  probable,  I  may  not  myself  be  so  for- 
tunate as  to  re-encianter  it,  it  will  most  likely  be  found  by  other 
observers,  and  far  better  treated  of.  For  the  present  purpose  it  is 
enough  to  mention  that  this  form  is  of  an  orange  or  buff  colour,  glo- 
bose its  "  normal"  figure,  but  is  capable  of  much  alteration  of  outline, 
and  it  is  furnished  with  numerous  linear  pseudopodia.  Now,  the  point 
worth  mentioning  here  is,  that  it  possesses  the  power  to  eject  with 
force,  and  rapidly,  a  considerable  number,  or  (one  might  say)  to  "fire 
off"  a  simultaneous  ** volley"  of  its  own  orange  granules,  from  all 
round  its  periphery,  to  a  distance  equal  to  the  length  of  its  pseudo- 
podia, and  with  an  amount  of  energy  and  consentaneousness  which  is 
truly  surprising;  no  sooner,  however,  have  the  granules  reached  a 
tolerably  equidistant  limit  from  the  periphery,  than  they  begin  to 
return,  but,  by  comparison,  much  more  slowly,  and  they  become  re- 
absorbed into  the  general  central  mass.  This  curious  action  I  have 
happened  to  see  on  only  two  or  three  occasions,  and  under  only  a  low 
power ;  I,  of  course,  immediately  turned  on  a  higher  power,  but  the 
performance  so  rapidly  accomplished  was  over,  nor  would  the  perverse 
thing  repeat  it.     Other  similar  forms  evince  comparable  phenomena  in 


Archer — Chi  Chlamydomyxa  LabyrinthuloUles,  147 

a  leas  pronounced  degree.  But  the  question  comes  up,  how  was  this 
remarkable  action  effected?  The  little  balls  were  suddenly  ejected 
and  gradually  retracted,  each  in  a  quite  straight  radial  Ime;  they 
must  have  been  held  in  by  something,  or  they  would  have  been  shot  off 
beyond  recovery,  either  by  a  minute  special  cord  of  sarcode,  rapidly 
evolved  and  again  gradually  retracting,  or  they  must  have  passed  either 
in  or  along  the  linear  pseudopodia.  If  they  passed  up  the  middle  of  the 
pseudopodium,  it  must  be  capable  of  great  distension,  or,  if  upon  the 
pseudopodium,  they  would  seemingly  be  thrown  off  beyond  retrieval, 
uidcss  (like  Actinosphserium)  there  were  a  subtle  enclosing  sheath 
over  a  central  axis  to  keep  them  in.  Whether  then  it  is  possible  to 
compare  the  modus  operandi  of  the  rapid  movement  of  the  round 
orange  granules  of  the  rhizopod  alluded  to,  if  on  the  pseudopodia, 
with  the  slow  gliding  action  of  the  **  spindles"  on  the  filtiform  threads 
in  the  present  organism,  may  be  a  matter  of  question. 

Not  less  singular  and  curious  than  the  spindles  are  the  filamentary 
tracks  upon  which  they  travel.  There  is  no  perceptible  differences  in 
their  width,  or  rather  tenuity,  either  near  the  great  main  trunk,  or  at  the 
remotest  extremity,  or  after  a  ramification.  The  main  trunk  and  the 
branches  differ  in  size,  as  has  been  said,  and  a  branch  may  become  so 
nnall  as  to  show  the  contained  granules,  evidently  within  it,  in  single 
file,  and  even  of  that  degree  of  slendemess  it  is  still  recognisable  as  a 
branch,  and  it  is  at  least  as  wide  as  a  single  granule  or  spindle.  But 
the  filamentary  tracks  proper  are  (by  comparison)  much  narrower 
than  the  spindles,  appear  like  delicate  **  silvery"  lines  (eluding  obser- 
vation sometimes,  owing  to  being  out  of  focus),  and  they  do  not  give 
the  idea  of  having  the  spindles  in  them  (as  does  the  finest  branch), 
but  on  them,  even  when  doubtless  they  are  upon  its  upper  or  lower 
side,  in  relation  to  the  observer.  They  are  given  off  &om  all  parts, 
even  from  the  hinder  portion  of  the  mass  still  within  the  envelope, 
and  it  was  not  unfrequent  to  see  a  few  spindles  travelling  from  the 
margin  of  the  body-mass  to  the  wall.  Further,  it  used  not  be  unfre- 
quent to  see  in  a  well-stretched  out  example  that  the  granules  remain- 
ing behind  embedded  in  the  mass,  still  in  the  head-quarters,  showed 
more  or  less  of  a  reticulated  arrangement  in  rows,  as  if  due  to  the  pre- 
sence of  some  of  the  filiform  tracks  permeating  the  interior  of  the  un- 
issued mass.  (Fl.  14.)  Still  my  impression  would  be  that  these 
remarkable  linear  tracks  are  comparable  rather  to  pseudopodia,  that  is, 
that  they  are  sarcode  prolongations  evolved  |^o  tempore ^  and  that  there 
does  not  pre-exist  a  store  of  them,  as  it  were,  coiled  up  inside,  waiting 
the  occasion ;  on  ''  squeezing"  one  of  these  no  trace  of  them  is  seen  in 
the  mass.  Unlike  the  axis  of  the  pseudopodia  of  Actinospheerium,  I 
have  not  seen  that  they  penetrate  downwfu^s  into  the  portion  of  Uie 
mass  whence  they  emanate,  and  hence  one  of  the  most  singular  puzzles 
is  that  the  little  globular  body  about  to  travel,  which  without  doubt 
is  distinctly  in  the  general  mass,  when  it  passes  to  the  base  of  the 
filamentary  track,  ascends  it,  becomes  fusiform,  it  now  appears  on  it. 

I  have  repeatedly  tried  in  a  variety  of  ways,  by  reagents,  &c.,  to 


148  Proceedings  of  the  Royal  Iriah  Academy, 

make  out  any  structure  of  the  nature  of  a  nucleus  in  this  organism,  but 
in  this  I  have  failed.  I  could  neither  find  a  nucleus  (as  in  Amoeba, 
Famphagus,  Plagiophrys,  Diaphoropodon,  &c.)  imbedded  in  the  general 
mass,  nor  in  the  spindles  themselves.  The  general  mass  is  made  up  of 
the  stilictures  alluded  to,  and  the  spindles  appear  only  as  bluish 
plastic  and  quite  homogenous  bodies,  as  described. 

Foreign  incepted  bodies,  generally,  if  not  always,  algse,  were  not 
infrequent.  Sometimes  one  can  see  through  even  a  densely  filled  and 
thickly  enveloped  and  hermetically  closed-in  example  the  **  digested" 
and  defunct  remains  of  perhaps  a  Cosmarium  or  Euastrum,  &c.,  or 
an  Oocystis  or  some  such  organism.  (PL  14).  The  large  example 
figured  shows  a  brown  and  dead  Cosmarium  cueurbita,  in  another  place 
an  Oocystis  Naegelii,  equally  brown  and  dead  (but  the  characteristic 
arrangement  of  the  endochrome  not  wholly  lost),  whilst  next  the  ex- 
tremity has  been  incepted  an  as  yet  scarcely  altered  example  of  a  new 
and  minute  Spirotsenia.*  Around  this  has  been  consolidated  the 
Barcode  mass,  which  all  the  time  gives  off  its  filamentary  tracks  and 
spindles',  the  Spirotsenia  embedded  in  its  midst. 

Several  times  I  have  kept  such  glorious  examples,  as  that  figured, 
on  a  growing  slide ;  after  some  hours  the  ramifications  were  drawn  in, 
and  there  remained  nothing  but  a  *'  shapeless"  mass  sticking  partially 
out  of  the  torn  opening  of  the  envelope,  or  all  had  wholly  disappeared. 
I  never  succeeded  in  directly  tracing  it,  but  there  can  be  no  doubt 
such  can  wholly  retract  and  again  secrete  a  wall,  and  completely  shut 
itself  up.  "Indeed  it  appears  probable  that  an  isolated  or  detached 
portion  of  the  mass  left  apart  also  can  so  encyst  itself— one  might 
almost  say  indeed  that  this  organism  appears  to  have  an  abhorrence 
to  remain  long  without  a  cyst;  nay,  even  though  seemingly  the 
sarcode  portion  may  not  have  emerged  and  offered  the  grand  arbores- 
cent condition  at  all,  still  the  contained  mass  will  keep  secreting  a  new 
coat,  and  adding  yet  another  lamina  to  its  perhaps  already  many  strati- 
fied and  much  thickened  envelope.  And  so,  seemingly,  after  several 
egresses,  retractions,  recoatings,  or  subdivisions  inwardly,  and  fresh 
recoatings,  are  brought  about  the  numerous  and  manifold,  often  outrS^ 
shapes,  in  the  encysted  and  dormant  state  assumed  by  this  organism. 

Anxious  to  find  anything  to  indicate  a  reproductive  process,  I  have 
delayed  to  bring  f orwaoxl  even  this  so  crude  an  account  of  this  form ; 
but  in  that  hope  I  have  failed.  The  only  thing  pointing  thereto  is  a 
subdivision  of  the  contents,  sometimes  noticed,  into  a  considerable 
number  of  generally  equal  parts,  sometimes  a  variation  in  size  is 
noticeable.  (PI.  15,  fig.  3.)  These  are  globular  in  figure,  and  seem  at 
first  to  be  without  any  wall.  Such,  kept  for  a  time  on  a  slide,  by-and- 
by  collapse  shapeless ;  if  they  had  a  wall  they  would  not  do  so.     But, 

♦  Spirottenia  graciUima  (n.  s.  milii),  very  minute,  linear,  extremely  slender,  very 
slightly  tapering,  apices  blunt,  spiral  turns  very  numerous ;  a  remarkable  form,  from 
its  extreme  slendemess.  Breadth  aAo  to  io6oo"i  about  twenty  to  thirty  times 
longer  than  broad. 


Archeb — On  Chlamydomycta  LahyrinthuhideB.  149 

ttXBb  to  the  idiosyncrasy  of  this  organism^  in  a  normal  state,  each  of  the 
balls  is  not  long  without  forming  a  special  wall  (as  in  the  fignre),  9sA 
a  number  of  globular,  smooth,  simple-walled,  secondary  indiyiduals 
are  produced  in  the  cavity  of  the  large  multilaminated  primary  one. 
One  sees  before  one  an  object  something  like  an  oogonium  of  a  Sap- 
rolegnia,  but  there  does  not  appear  any  analogy  between  them. 

Such  is  an  attempt  to  convey  an  idea  of  this  organism,  which  may 
perhaps  stand  for  the  present  as  Chlamydomyxa  l^yrintkuloidea,  as  it 
presented  itself  in  the  natural  condition,  especially  the  first  and 
second  seasons  of  my  making  its  acquaintance.  A  word  or  two  is 
requisite    as    regards    the    appearances    under    the    application    of 


I  was  surprised,  on  applying  iodine  and  sulphuric  acid,  to  find  that 
this  curious  multilaminated  coat,  so  conspicuous  a  portion  of  the  make- 
up of  this  organism,  gave  a  brilliant  indigo  blue  colouTf  accompanied  by 
a  great  swelling  up  of  the  constituent  laminse,  the  outer  of  which  took 
somewhat  of  a  violet  colour.  (PI.  15,  fig.  6.)  In  other  words,  this 
coat  gave  in  a  marked  manner  the  cellulose  reaction.  At  same  time 
the  inner  basic  substance  acquired  a  pale,  homogeneous,  somewhat  ver- 
digris green  hue,  and  the  granules,  a  brassy  or  yellowish  colour,  and 
shmy  appearance,  and  became  simultaneously  of  quite  a  spherical 
figure,  and  rather  small  and  regular  size,  each  with  a  dark  contour. 

Boiled  in  caustic  potash,  a  great  sweUing  up  and  separation  of  the 
outer  laminse  of  the  coat  took  place ;  to  some  extent,  the  same  in  cold 
potash ;  the  basic  substance  assumed  a  ySUowish,  sometimes  faintly 
greenish,  hue,  and  the  granules  became  perfectly  globular,  more  varied 
in  size  than  under  the  iodine  and  sulphuric  acid,  but  quite  oily  and 
shiny  in  appearance,  and  of  a  greenish-yellow  colour.  (PL  15, 
fig.  5.) 

In  Beale's  carmine  solution  no  very  marked  change  ensued,  and,  as 
before  mentioned,  no  portion  showed  itself  anywhere  as  a  nucleus,  nor 
did  any  portion  take  indeed  any  extra  dye. 

Alcohol  deprived  the  red  granules  of  their  colour,  and  changed  the 
whole  contents  to  a  somewhat  greenish-yellow. 

Such  were  the  results  of  reagents  on  this  curious  oi^anism,  as  it 
j»«8ented  itself,  the  first  and  second  season  of  my  meeting  with  it. 
Since  then,  much  to  my  vexation,  I  have  failed  to  encounter,  except 
very  rarely,  examples  displaying  the  active  condition  described ;  but 
it  always  now  presents  itself  closely  wrapped  up  in  its  coat,  and 
densely  filled  with  a  preponderance  of  red  granules.  In  that  condition 
it  is  prone  to  occur,  in  considerable  quantities,  on  the  submerged  surface 
of  aquatic  plants  in  the  pools  which  it  affects.  The  very  first 
examples  I  met  with  were  free  at  the  bottom  of  the  pool ;  and  I  there- 
fore tried  to  examine  this,  to  me,  new  phase  more  closely. 

The  first  plant  on  which  I  noticed  this  was  Sphagnum,  but  I  soon 
found  that  this  was  only  because  other  aquatics  were  more  scarce  in 
the  pool ;  for  the  submerged  leaves  of  sedges,  of  Eriophorum,  &c.,  and 

B,  I.  A.  PBOC,  8BR:  n.,  VOL.  II.,  SCIENCE.  X   ' 


150  ProccedingH  of  the  Royal  In^h  Academy. 

more  lately  still,  I  noticed,  in  Connemani,  that  IHocaulon  »ept4mgular0 
also  suited  this  organism  as  a  host. 

On  examining  a  piece  of  Sphagnum,  or  other  plant  bearing  this 
production,  it  may  be  often  seen  that  the  indiyiduals  are  attached, 
sometimes  in  crowds,  sometimes  singly,  by  one  of  the  before-mentioned 
neck-like  prolongations,  forming,  as  it  were,  a  broad  isthmus  or  neck, 
joining  the  great  globose  or  lobed  portion  to  the  plant,  but  at  other 
times  they  seem  to  lie  thereon  without  any  evident  union  with  it. 
They  are  of  variable  size,  and,  as  mentioned,  of  most  variable  shape. 

But  on  closely  scrutinising  some  of  the  8phagnum-leaTes  (ulti- 
mately other  leaves),  I  was  still  more  surprised  to*  find  very  imaU 
examples,  with  a  simple  wall,  or  perhaps  with  a  wall  of  two  laminae, 
unmistakably  tiMt^  the  large  hyaline  cells,  with  annular  and  spiral 
fibre.  (PL  15,' fig.  2.)  These  Httle  examples  were  in  every  re^>ect 
(except  size  and  number  of  laminae  of  the  coat)  like  the  extcznal 
lai^er  ones;  very  small  ones  were  of  an  ellipsoidal  or  subglobular 
figure,  but  larger  ones,  not  uncommonly,  showed  an  elongate  torulose 
figure,  simply  due  to  the  example,  now  enlarging  so  as  to  fill  the  cell, 
becoming  at  intervals  cinctured  about,  and  by  reason  of  its  expan- 
sive growth  being  constricted,  by  the  recurring  annular  fibres  of  the 
Sphagnum-cell.  (PL  15.,  fig.  2,  middle  and  left.)  Other  cases  could 
be  found  where  such  little  examples  protruded,  hernia-like,  on  the 
suiface  of  the  leaf.  Thereupon  the  ''sarcode,"  with  the  granular 
colouring  contents,  seem  to  pass  up  into  the  protrusion ;  then,  true  to 
its  propensity,  to  form  a  fresh  coat,  leaving  behind  the  original  one, 
and  thus  seemingly  explaining  how  these  bodies  ceme  to  cover  the 
leaf  here  and  there,  attached  thereto.  (PL  15,  fig.  2,  to  right)  No 
due  whatever  have  I  been  able  to  obtain  as  to  how  these  bodies  origi- 
nally get  into  the  cavity  of  the  leaf-cell,  or  how  their  "germs"  can 
enter.  No  doubt,  in  Sphagnum,  one  could  suppose  small  germs  could 
enter  through  the  pre-existent  openings  or  foramina  in  the  wall  of  the 
hyaline  cells,  and  through  the  same  openings  the  hernia-like  protru- 
fiions  could  make  an  exit  without  any  material  injury  to  the  Sphagnum  ; 
for  it  is  true  that,  for  a  length  of  time,  it  can  thus  harbour  this 
cyrganism  without  seeming  itself  to  suffer.  But  though  this  is  so,  it  is 
no  less  true  that  when  this  organism  at  last  gro¥rs  to  excess,  the 
Sphagnum  succumbs,  gets  eventually  broken  up,  the  tissue  of  the 
'^leaves"  disappearing,  and  nothing  left  but  the  '*stem"  and 
*^  branches  "  covered  by  this  growth,  and  such  portions  seem  to  be  at 
last  utterly  "killed." 

But  if  it  were  supposed  that  in  Sphagnum  "  germs  "  could  make 
their  way  through  the  foramina  in  the  cells  of  the  leaves,  the  same 
supposition  would  not  hold  good  as  regards  other  plants,  wiUiout  such 
normal  openings  in  the  cells.  Of  such,  none  offers  a  more  striking 
example  than  the  cells  (of  the  roots)  of  Eriocaulon.  Of  this  curious 
plant,  small  specimens  are  sometimes  found  floating  on  the  sur&ce  of  the 
water,  and  though  defunct,  their  tissues  seem  not  in  any  way  injured 
or  disturbed.     Inside  the  celU  of  this  plant  small  examples  of  this 


Aecher — On  Chlamydomyxa  Lahyrinthuloides.  .        151 

organism  are  Bometime6  to  be  f ound,  to  all  appearance  hermetically 
cloeed  in,  and  without  any  evident  mode  of  ingress.  But  it  would  be 
unreasonable  to  suppose  that  it  could  be  self-generated  in  the  plants  it 
inhabits.  Other  endoparasites,  penetrating  from  without,  as  is  well 
known,  exist.  In  other  leaves,  where  it  can  be  seen  occupying  inter- 
cellular spaces,  the  marvel  becomes,  of  course,  very  much  dinunished. 
It  may  be  found  (in  Connemara)  coveiing  Batracho9permum  vayum, 
and  lodged  in  numbers  between  the  cortical  layer  of  filaments  depend- 
ing from  the  nodes,  which  become  dislocated,  and  portions  of  the  pldnt 
distorted ;  but  such  is  not  very  surprising.  But  as  to  how  this  produc- 
tion gets  into  cells  of  several  diverse  plants,  inhabiting  the  same  pool, 
is  a  mystery  to  which  I  regret  I  have  no  clue. 

In  certain  leaves  of  Sphagnum  in  which  unmistakable  young  in- 
dividuals occur,  and  again  in  others  in  which  such  did  not  reveal 
themselves  (not  always,  however,  absolutely  critically  examined), 
certain  growths  can  be  se^n,  generally  somewhat  to  one  side  of  the 
hyaline  cell,  and  sometimes  pressing  in  upon,  and  distorting,  the  inter- 
mediate chlorophyll-bearing  cells.  These  form  elliptic,  greenish, 
coarsely  granular  masses,  surrounded  by  an  irregular,  colourless  hya- 
line, indistinctly  bounded,  roughly  stnate  covering.  (Fl.  15,  fig.  1.) 
Sometimes  two  of  these  may  occur  in  one  cell,  and  if  at  the  same  level, 
or  side  by  side,  they  together  may  press  more  upon  the  adjacent  cells, 
and  cause  somewhat  more  marked  distortion.  I  have  not  been  able  to 
satiBfy  mysdf  that  these  have  a  genetic  relationship  to  the  subject  of 
Una  paper,  but  I  am  inclined  to  think  they  may  have. 

Altiiough,  then,  no  ''reproductive"  condition  or  development  of 
*^  germs  "  of  any  kind  has  ever  rewarded  my  repeated  collection  and 
examination  of  this  organism,  at  difPerent  periods  of  the  year,  so  far  as 
I  am  awaiB,  nothing  essentially  agreeing  vnth  its  general  and  special 
characteristics  has  before  been  described.  But  one  cannot  look  at 
Cienkowski's  figures  of  his  Labyrinthula-forms,  or  read  his  account  of 
them  (loe.  cit),  without  being  struck  with  the  strong  resemblance,  if, 
indeed,  it  may  not  turn  out  to  be  more.  . 

It  becomes  necessary,  then,  to  refer  to  the  descriplion  given  by 
Cienkowski  (loe.eit.),  of  the  two  forms  for  which  he  founded  the  genus 
Labyrinthula,  and  the  only  one  of  the  new  group  "  Labyrinthulese." 

Labyrinthula  viteUinay  Cienk.,  forms  little  brick-red,  or  orange- 
coloured  patches,  about  the  size  of  a  pin's  head,  upon  seaweeds  cover- 
ing the  piles  in  Odessa  harbour.  Placed  under  the  microscope,  and 
allowed  to  repose  for  some  hours  (say  twenty-four),  three  principal 
constituents  catch  the  eye  of  the  observer :  tne  "  central  mass,"  the 
"spindles,"  and  the  "filamentary  tracks"  ("Fadenbahn,"  Cienk.). 
The  "  central  mass"  consists  of  globules  (0*012  mm.  in  diam.),  with  a 
very  delicate  contour,  and  of  a  brick-red  or  yelk-yellow  colour,  which 
in  the  aggregate  are  held  together  by  a  delicate,  finely  granular,  basic 
substance,  often  presenting,  externally,  a  thin  colourless  margin. 
Passing  off  therefrom  in  various  directions  are  seen  numerous  slender, 
mostly  very  thin,  anastomosing  strings,  the   "filamentary  tracks." 


152  Proceedings  of  the  Bx>yal  Irish  Academy. 

Towards  the  periphery  of  the  masB  the  little  orange-coloured  globules 
acquire  a  more  elliptic  figure,  and  they  can  be  watched  passing  up, 
one  by  one,  upon  the  tracks,  where  they  assume  a  fusiform  figure,  and 
gradually,  but  very  slowly,  glide  onwards.  In  the  course  of  several 
hours,  the  greater  part  of  these  little  bodies  have  ascended  the  tracks, 
and  slowly  pursued  their  way  to  the  mai^in  of  the  drop  of  water.  It 
is  therefore  clear  the  little  globules  at  first  seen,  and  the  '*  spindles  " 
afterwards  found  travelling  on  the  slender  tracks,  are  identical.  Their 
contour  is  very  delicate,  they  never  become  fused,  though  do  not  seem 
to  possess  any  evident  membrane.  The  middle  of  each  is  occupied  by 
*'  a  nueletUf  appearing  like  a  clear  vacuole,  enclosing  a  strongly  refrac- 
tive nucleolus;"  they  increase  in  number  by  self -division,  and  are 
hence  to  be  regarded  as  true  **  cells."  Treated  with  tincture  of  iodine, 
a  sharply  circumscribed  contour  makes  its  appearance  on  their  suifaee, 
becoming  brown,  and  standing  o£P,  more  or  less,  from  the  contents. 
Alcohol  dissolves  the  pigment,  leaving  the  globules  deprived  of  colour ; 
the  spindles  so  treated  do  not  become  blue  by  iodine,  which  at  once 
takes  place  when  tincture  of  iodine  is  added  to  fresh  material ;  allowed 
to  operate  longer,  the  whole  spindle  becomes  dark  brown.  The  beha* 
viour  of  the  pigment  under  sulphuric  acid  shows  it  belongs  to  the 
category  of  colouring  substances,  forming  the  red  specks  {"  eye  dots  ") 
of  Euglenee,  Eotatoria,  the  orange-yeUow  contents  of  Uredines.  They 
are  very  contractile,  altering  their  figure  on  contact  as  they  glide 
along.  Their  main  direction  is  centrifugal,  towards  the  margin  of  the 
drop  of  water  in  which  they  are  under  observation,  but  they  do  not 
always  take  the  shortest  course ;  they  appear  also  capable  of  gliding 
over  one  another ;  some  of  them  thus  delayed  en  route  may  preserve 
their  original  globular  figure  but  having  passed  the  obstacle,  upon  at 
fresh  start  the  fusiform  figure  is  reassumed.  Sometimes,  says  the 
author,  a  backward  motion  may  take  place,  'though  indeed  the  final 
exit  from  the  water  appears  to  be  the  purpose  of  this  curious  wander- 
ing." As  to  the  cause  of  the  movement,  the  author  knows  of  no  fact 
capable  of  leading  to  an  explanation,  being  of  opinion,  however,  that^ 
**^  owing  to  the  rigidity  of  the  track,  the  cause  is  to  be  sought  in  the 
spindles,  though  the  latter,  away  from  the  track,  have  not  the  power 
to  move." 

Touching  the  "  tracks "  themselves,  the  author  seems  to  regard 
them  as  not  differing  except  in  tenuity  from  the  general  hyaline  basic 
substance.  He  was  able,  by  the  application  of  acetic  acid,  to  perceive 
that  the  previously  seemingly  uniform  substance  now  showed  a  very 
fine  fibrous  structure,  and  pressure  on  the  covering-glass  enabled  him 
to  detach  the  strings  from  the  central  body.  When,  however,  the 
whole  fabric  becomes  fully  evolved  under  the  microscope  (that  is,  the 
whole  *'  tree  "  or  **  labyrinth  "  developed),  it  seems  to  possess  no  con- 
tractility, evinces  no  movement  on  the  surface  or  in  the  interior,  no 
projection  or  retraction  of  processes  or  rays  comparable  to  the  pseudo- 
podia  of  the  Ehizopoda :  the  whole  is  now  a  rigid,  motionless  structure 
(except,  of  course,- the  wandering  spindles).     The  author  would  leave 


Archer — On  Chlamydomyxa  Lahyrinthuloidea.  153 

the  question  an  open  one  as  to  '^  whether  the  tracks  represent  a  system 
of  communicating  tubes,  or  solid  interwoven  threads." 

The  principal  difficulty  in  his  arriving  at  a  conclusion  is  due  to  the 
extreme  minuteness  of  the  threads,  which  scarcely  allows  of  the 
mutual  relation  of  these  to  the  spindles  being  observed.  The  author 
could  not  satisfy  himRelf  as  to  whether  the  spindles  executed  their 
movement  in  a  single  thread  or  between  two  of  them ;  as  he  regards 
the  passage  of  a  spindle,  from  the  main  filament  to  branch,  as  being 
compatible  with  either  interpretation.  Also,  he  says  the  &ct  that, 
upon  the  application  of  iodine,  the  contour  tlien  seems  as  standing  off 
from  the  spindles,  directly  continued  above  and  below  into  the  fila- 
ments, may  be  used  in  favour  of  either  view ;  this  contour,  with  its 
dependent  threads,  may  be  interpreted  as  the  expression  of  a  ''  tube 
in  which  the  spindle  moves,  or  as  that  of  two  threads  in  contact 
longitudinally."     The  author  himself  leans  to  the  latter  view. 

Notwithstanding  the  seeming  fihrous  nature  of  the  mass  under 
certain  circumstances,  and  occasional  tuft-like  pencils  of  short  linear 
prolongations  making  themselves  sometimes  apparent,  Cienkowski 
thinks  there  is  not  thereby  afforded  a  reply  to  the  query  whence 
properly  the  material  to  form  the  tracks  proceeds ;  is  it  the  basic  sub- 
stance of  the  central  body  which  breaks  up  into  the  interwoven 
threads,  or  is  it  the  spindles  themselves  which  directly  build  up  the 
whole  framework?  He  replies,  that  naked  clusters  of  spindles,  or 
even  isolated  spindles,  without  combining  basic  substance,  are  so 
capable,  and  that  the  latter  takes  no  share  in  fonning  the  aggregate 
framework;  but  whether  only  the  apices  of  the  spindles  or  their  whole 
surfaces  contribute  to  emit  it,  he  exprosses  himself  as  uncertain. 

The  other  species  described  by  Cienkowski,  Z.  maeroctfstis,  agrees  in 
all  essential  points  with  the  foregoing.  Its  spindles  are  larger  (0*01  B 
to  0*025  mm.),  of  firmer  consistence,  the  nucleus  more  sharply 
marked,  the  contents  more  granular,  than  in  Z.  viteUina,  and  they  are 
colourless,  or  a  pale  yellow  tint.  I^either  iodine  nor  sulphuric  acid 
produces  a  blue  colour.  As  in  the  previous  species,  the  spindles  in- 
croase  by  self -division.  This  form  occurs  on  the  piles  at  a  higher 
elevation  than  the  preceding,  therefore  not  submerged  except  by  the 
sxirf.  Hence  it  is  regarded  by  the  author  as  exphcable  why,  in  this 
form,  the  spindles  are  more  prone  to  pass  into  a  '^  cyst"  or  ''  spore." 
Preparatory  thereto,  the  cells  enlarge,  become  more  richly  granulate, 
darker  in  colour,  the  spindles  become  oval,  and  each  acquires,  besides 
its  own  membranous  covering,  a  thick-waUed  smooth  envelope;  the 
basic  substance  possesses  a  glassy,  rather  firm,  consistence,  retaining 
the  outline,  like  a  ''mould"  or  matrix,  of  such  '' cysts"  as  are  ejected 
byforee ;  on  the  surface  of  the  cluster  there  is  formed  a  granular  layer 
ol  darker  colour  than  in  the  interior.  After  a  pause,  the  contents  of 
the  encysted  ''  spindles"  become  divided  intg  four  portions,  the  coat 
disappears,  and  they  remain  free,  as  motioidess  globules.  This  taking 
place,  in  many  instances  produce  numerous  closely  lying  little  groups. 


154  Proceedings  of  the  Boyal  Irish  Academy. 

the  little  bodies  soon  assuming  the  fusifonn  figure,  already  acoom- 
panied  bj  the  ''  tracks,"  indispensable  for  their  movements. 

Such  is  a  very  much  epitomised  abstract  of  the  author's  memoir, 
and  he  sums  up  the  conception  of  the  Labyrinthule®  as  follows : — 

1.  Clusters  of  nucleus-containing  cells,  increasing  by  division, 
possess  a  certain  degree  of  contractility,  at  tunes  becoming  enclosed  in 
a  basic  substance. 

2.  These  cells  give  off  a  fibrous  substance,  which  becomes  formed 
into  a  rigid  structure,  forming  reticulations  and  arborescent  ramifica- 
tions. 

8.  The  cells  leave  the  clusters,  gliding  away,  by  manifold  cir- 
cuitous routes,  to  the  periphery  of  the  drop,  but  the  Labyrinthula- 
ceUs  can  carry  on  their  wandering  only  when  supported  by  these 
filamentary  tracks. 

4.  The  wandering  cells  combine  anew  in  clusters,  and  pass  over 
into  an  encysted  state,  each  cell  acquiring  a  firm  envelope,  all  held 
together  by  the  common  basic  substance. 

5.  From  each  cyst,  after  a  rest  of  some  time,  four  globules  are 
formed,  which  extremely  probably  become  changed  into  young  Laby- 
rinthula-cells. 

Thus,  notwithstanding  the  great  resemblance,  there  are  some 
points  of  difiterence,  of  such  seeming  great  importance  as  possibly  to 
forbid  the  present  organism  being  subordinated  to  the  Labyrinthuleee. 
In  the  first  place,  the  ^*  spindles"  are  not  nucleated;  in  the  next,  they 
do  not  (seemingly)  ever  become  themselves  encysted,  but  the  aggregate 
group,  matrix,  colouring  granules  and  all,  become  repeatedly  so,  and 
that  in  a  cellulose  coat;  in  the  third  place,  Cienkowski's  Labyrin- 
thulesB  do  not  possess  other  colouring  granules  besides  the  spindles — 
in  the  present  form  there  are  green  and  red  alternating ;  and,  in  the 
fourth  place,  the  former  do  not  show  contractile  vacuoles,  a  con- 
spicuous feature  in  the  latter,  under  certain  conditions;  nor  did. 
Cienkowski  see  any  organisms  incepted  into  their  mass ;  and,  lastly, 
Cienkowski's  forms  did  not  evince  any  parasitic  nature. 

The  first  objection  seems  to  be  the  most  important.  Might  it, 
however,  possibly  be  met  by  assuming  the  spindles  in  the  present  form 
to  be,  as  it  were,  all  nucleus?  Cienkowski  offers  no  conjecture  as  to 
any  seeming  or  probable  purpose  of  the  strange  wandering  of  the 
spindles,  save  "to  reach  the  periphery  of  the  drop,  or  to  get  out  of  the 
water;"  still  he  says  they  can  recede.  Their  object  would  naturally 
seem  to  be  to  transport  to  a  distance  from  the  primary  mass,  and  to 
distribute  around,  the  spindles,  in  order  to  lay  the  foundation  of  a 
number  of  new  centres.  Quite  in  a  similar  manner,  the  spindles  in 
the  present  form  tend  to  pass  away  from  the  original  centre,  and 
masses,  accompanied  indeed  by  a  greater  or  less  quantity  of  the  basic 
matrix,  are  sometimes  left  apart  to  form  new  centres.  I  cannot  say, 
indeed,  whether  or  not  a  single  spindle  would  have  the  power  to  lay 
the  foundation  of  a  new  and  independent  centre  of  growth,  like  to 


Archer — On  Chlamydomyxa  Labt/rinthuhidea.  155 

that  which  it  left  behind;  bnt  it  might  not  be  unreasonable  to  suppose 
that  in  this  way  the  slender  filamentary  tracks,  reaching  far  and  wide, 
may  be  simply  the  medinm  of  transporting  to,  and  depositing  these 
spindles  wiiJiin,  the  tissues  of  the  adjacent  submerged  plants,  in  the 
way  which  we  have  seen  it  to  occur,  there  to  develop. 

As  to  the  second  objection,  that  the  individual  spindles  do  not  be- 
come specially  encysted,  but  the  whole  of  them,  along  with  the  other 
granular  stmctnres  in  common,  might  be  only  of  secondary  import- 
ance ;  more  cogent,  indeed,  is  it,  perhaps,  that  liiey  have  not  been  seen 
to  dwide^  but  after  all  it  is  a  probable  way  of  their  increase. 

The  remaining  objections  seem  rather  to  relate  to  questions  of 
habit,  or  might  be  considered  in  themselves  as  touching  upon  points 
rather  of  mere  '^  specific "  signification  than  of  higher  import. 
Cienkowski's  forms  might  yet  prove  to  be  parasitic ;  they  at  least 
grow  upon  and  surround  the  adjacent  algee.  Cienkow^'s.  forms  took 
some  twenty-four  hours  on  a  **  slide"  to  grow  up  into  a  "  tree"  like 
that  shown  in  his  figures ;  the  present  form  has  often  presented  a 
spectacle  like  that  shown  in  PL  14,  in  less  than  as  many  minutes. 

If  the  spindles  in  my  form  were  nucleated,  i.  e.  if  they  represented 
''cells,"  not  merely  plastic,  homogeneous,  little  masses,  the  present 
organism  would  seem  to  be  necessanly  relegated  to  the  Labyrinthulese, 
apart  from  the  other  points  of  difference. 

The  ''filamentary  tracks"  in  Cienkowski's  forms  and  in  the  present 
organism  seem  wonderfully  to  resemble  each  other,  so  much  so  that, 
whatever  be  their  mode  of  evolution,  it  is  probable  this  is  alike  in  all. 
As  has  been  seen,  Cienkowski  ascribes  the  origin  of  the  filamentary 
tracks  to  the  spindles  themselves — ^in  other  words,  a  spindle  must  exist 
before  a  track ;  the  former  must  first  exude  or  give  off  the  filamentary 
substance  ("  faserige  Substanz"),  then  pass  along  (?),  or  in  (?),  or 
between  (?),  the  threads  so  produced,  but  which  the  author  leaves  an  open 
question.  But  this  does  not,  seemingly,  quite  coincide  with  his 
description  of  the  basic  substance,  a  "zarte,  feinkomige  Sinden- 
Substanz,"  often  forming  at  the  periphery  a  thin  enveloping  layer, 
where  again  its  substance  is  spoken  of  as  either  "  ganz  hydin,  einfor- 
mig"  or  as  showing  a  "sehr  feine  faserige  Structur,"  and  where  it  has 
the  power  to  give  off  branches,  of  a  glassy  appearance,  gradually 
tapeiing  off;  these  may  be  of  a  uniform  appearance,  or  show  a  very 
fine  fibrous  (faserig)  structure,  and  at  the  margin  sometimes  running 
off  into  very  thin,  scarcely  perceptible  rays,  sometimes  fringe-like,  at 
others  tufted,  and  all  this  seemingly  without  the  direct  presence  of 
any  of  the  spindles.  These  fine  linear  threads  seem  to  be  nothing 
more  nor  less  than  the  "  tracks,"  as  yet  very  short.  In  one  form  the 
tracks,  if  I  mistake  not,  are  given  off  independently  of  the  spindles, 
but  they  are  no  sooner  there  ti^an  spindles  are  seen  thereon  (or  there- 
in ?).  As  I  mentioned  as  regards  my  form,  and  as  will  be  seen  in  the 
figure,  a  more  or  less  reticulated  arrangement  of  the  "  spindles"  (not 
now  of  fusiform  figure)  may  be  seen  in  &e  interior  of  the  central  mass, 
suggesting  their  arrangement  along  "tracks"  enveloped  by  the  general 


156  Proceedings  o/t/ie  Royal  Irish  Academy. 

substance;  but  this  is  only  conjectural.  (PI.  14.)  In  ^^  Cienkowski's 
and  the  present  form  the  tracks  give  off  branches,  and  incorporate 
with  others  which  thej  cross,  admitting  of  the  spindles  taking  very 
circuitous  routes. 

In  Cienkowski's  forms  he  mentions  that  the  tracks  (rigid  as  they 
seem  at  first)  hy-and-hy  take  on  ''  a  mucous  consistence,  more  or  less 
enveloping  the  spindles,"  and  they  form  "  knot^like  expansions,  in  which 
vacuoles  occur;"  but  notwithstanding  these  facts,  the  author  regards 
the  tracks  in  such  condition  as  only  "  most  deceptively  presenting  the 
appearance  of  a  protoplasm-plate ;"  does  not  this  seem  somewhat  con- 
tradictory ?  In  our  form  the  tracks  seem  to  be  given  o£F  from  the 
central  mass  (pseudopodium-fashion),  and  can  be  wholly  or  partially 
retracted. 

Cienkowski  denies  to  the  spindles  any  power  of  motion  except  in 
eannectum  with  the  tra^ksy  but  in  both  of  his  and  in  the  present  form 
these  have  the  power  spontaneously  to  leave  the  general  crowd  inside 
the  central  mass,  at  first  without  apparent  contact  with  a  track,  then, 
propria  motu,  to  mount  the  one  along  which  it  is  to  make  its  journey. 

But,  further,  in  connection  with  a  fungal,  the  identity  of  which 
was  unknown  to  the  author  himself,  Cienkowski  had  previously  drawn 
attention  to  a  filamentary  form  of  plasmodium,  with  "  spindles"  mov- 
ing along  the  threads.*  This  he  describes  thus  (curtailed) : — "  Upon 
oidture  of  these  for  some  time  upon  a  slide,  I  found  the  entire  field 
covered  over  by  a  branched  network  of  threads,  which  here  and  there 
showed  fusiform  thickenings.  Upon  following  the  course  of  these 
threads  for  certain  distances,  large  differently-shaped  colourless  proto- 
plasma-masses  were  encountered,  from  which  the  whole  structure 
drew  its  material  as  from  a  reservoir — so  to  say,  budded  out  from  it. 
Upon  attentive  examination  of  the  plasma-aggregates,  it  rendered 
itself  apparent  that,  at  any  place  thereof,  a  projection  or  prominence 
first  makes  its  appearance.  This  prominence  becomes  constricted  at 
its  base,  assumes  a  fusiform  figure,  then,  removed  from  the  principal 
mass,  drawing  a  thread  with  it.  In  the  same  way  sprouts  out  from 
the  protoplasm  a  new  spindle,  which  likewise  thins  off  at  its  base  into 
a  thready  and  follows  the  one  first  formed.  Wbilst  thus  continuously 
new  spindles  and  threads  proceed  from  the  main  reservoir,  and  become 
carried  along  the  'track'  (' Fadenbahn'),  the  whole  thread  creeps 
forwards,  the  end  spindle  directed  foremost.  The  filaments  proceeding 
from  the  reservoir  are  to  be  identified  with  the  basic  substimce  of  the 
Plasmodium,  the  spindles  and  strings  with  the  granular  substance. 
The  movement  of  tiie  thread  is  extremely  slow,  scarcely  directly  per- 
ceptible, that  of  the  spindle  much  more  noticeable. 

**  En  route  the  spindles  may  not  be  equally  mutually  remote ;  here 
and  there  one  becomes  accelerated,  and  lays  itself  longitudinally  on 
the  one  preceding  it ;  this  is  followed  by  another,  and  so  on.     In  this 

*  Cienkowski;  "Das  Plasmoditun,"  in  Pringsheim's    '^ Jahrbiicher  fiir  wiss. 
Bot."     Bd.  iii.,  p.  408. 


Abcher — On  Chlamydomyxa  Ldbyrinthuloid4^t.      157 

way  origmates  a  cluster  of  spindles  whioh  fase  together  in  a  string, 
continuing  its  way ;  the  thread,  howeyer,  keeps  its  own  position  and 
extension.  We  are  thus  here  compelled  to  distinguish  between  the 
less  motile  basic  substance  and  a  second  gliding  one.  Another  inter- 
pretation, that  the  spindles  are  but  enlargements  of  the  threads,  whidif. 
become  moved  up  and  down,  is  inadmissible,  because  the  spindles,^  as 
we  have  seen,  considerably  alter  their  figure  en  route,  coalesce,  become 
divided,  and  proceed  from  the  main  reservoir." 

The  author,  at  the  conclusion  of  his  memoir*  on  the  Labyrinthulcae, 
again  refers  to  this  curious  'Tadenplasmodium"  appertaining  to  the 
unknown  fungal  (taken  by  him,  he  now  mentions,  from  the  earth  of 
some  flower-pots),  and  he  regrets  that  he  was  never  able  to  refind  it 
for  further  examination,  with  the  fresh  light  and  new  experience 
derived  from  the  study  of  the  two  marine  forms  constituting  his  new 
group  named  Labyrinthulece.  At  that  time,  as  is  seen,  he  regarded 
"the  central  balls  as  protoplasmic  bodies,  £rom  which  each  spindle 
upon  beginning  its  wandering  was  produced  by  constriction.  That  the 
spindles  pre-exist  in  the  central  clusters  as  such,  or  in  the  form  of 
globules,  was  then  a  fact  unknown  to  him,  whether  it  were  that  this 
diflferentiation  in  the  filamentary  plasmodium  (Fadenplasmodium)  was 
not  really  existent  at  all,  or  that  the  delicacy  of  the  object  and  the 
difficulty  of  observation  concealed  from  him  the  true  state  of  facts. 
The  filamentary  plasmodium  observed  under  a  covering  glass  always 
perished,  for  at  that  time  he  had  made  no  use  of  the  *  moist  chamber.' " 

There  is  thus  pretty  evidently  a  considerable  resemblance  in  this 
organism,  whatever  it  he,  to  that  herein  described. 

The  author  alluded  in  his  previous  memoir  on  the  Plasmodium  to 
this  ''enigmatical"  production,  in  order  to  compare  it  with  certain  very 
similar,  though  not  seemingly  at  all  identical  conditions  of  the  plasma 
of  certain  Mycetozoa.f  Bef erring  to  certain  filamentary  forms  assiimed 
thereby,  he  draws  attention  to  tiie  ''formation  of  lenticular  enlarge- 
ments of  the  basic  substance  of  the  threads.  The  number  and  size  of 
these  of  course  depend  upon  the  persistence  of  the  interruptions  of 
the  current,  as  also  upon  the  quantity  of  the  substance  flowing  on- 
wards after  each  interval  of  pause.  These  isolated  masses  of  the 
granular  substance  can  glide  along  the  thread  up  and  down,  approach, 
coalesce  into  a  larger  expansion,  or  become  removed  from  one  another; 
the  basic  mass  of  the  thread  remains  also  here  motionless." 

Now,  I  am  much  incHned  to  think  that  a  comparison  of  the 
phenomena  as  here  described  by  Cienkowski  for  the  Fadenplasmodium 
in  Mycetozoa,  with  those  evinced  by  the  organism  brought  forward  by 
me  in  this  communication,  still  less  a  determination  of  ti^ese  as  but  the 
expressions  of  similar  structures,  would  not  be  tenable.  The  appear- 
ances and  characteristics  evinced  by  my  form  seem  more  to  admit  of 
comparison  with  the  fungal  (from  the  flower-pot)  referred  to  by 

•  Loe.  eit.,  p.  308.  t  Loe.  cit,,  p.  40.5. 

K.  I.  A.  PaOC,  SEH.  II.,  VOL.  II.,  SCIENCE.  Y 


lo8  Proceedings  of  the  Royal  Irish  Academi/. 

CicnkowBki;  but  there  appear^  so  far  as  can  be  judged,  general  points 
of  difference— of  course  no  one  could  for  a  moment  regard  them  as 
identical.  If  we  judge  aright  from  Cienkowski's  figure,*  the 
^'spindles"  in  his  unknown  organism  (from  the  flower-pot)  do  not  seem 
of  differentiated  character  from  the  tracks;  they  seem  to  be  composed  of 
the  basic  substance,  and  to  contain  the  same  extremely  minute  granules, 
notwithstanding  that  they  haye  an  independence  of  movement.  Unlike 
the  marine  Labyrinthule«B,  they  do  not  seem  to  be  nucleated,  and  in 
that  respect  would  agree  with  those  of  my  organism.  But  in  the 
latter  the  "  spindles"  are  undoubtedly  pre-existent  in  the  central 
mass,  and  are  of  quite  different  colour,  consistence,  and  character  from 
the  basic  substance  containing  them,  or  the  **  tracks"  on  which  they 
travel. 

We  have  thus  to  do  with  an  organism  singular  in  its  details,  and 
highly  puzzling  as  to  its  real  nature — one  which  offers  but  few  re- 
semblances to  recognised  and  described  objects.  Its  outward  "facias" 
and  its  most  striking  resemblances  doubtless  suggest  affinity  to  the 
LabyrinthulesB,  especially  L.  vitellifia,  Cienk.,  but  this  may  be  a  mere 
resemblance,  nothing  more,  if  we  were  acquainted  with  its  develop- 
ment. It,  like  the  marine  forms,  has  a  resemblance  to  Cienkowski's 
as  yet,  even  to  him,  enigmatical  fungal  (from  the  flower-pot);  it  has  a 
less  striking  resemblance  to  conditions  of  Mycetozoa,  as  pointed  out 
also  by  Cienkowski.  In  the  absence  of  a  "nucleus"  it  agrees  with 
Monera  (Hackel).  But,  whilst  it  as  yet  shows  no  "fructification,"  no 
reproductive  process,  in  any  more  strict  sense  of  the  word,  a  decision 
as  to  its  real  nature  must  remain  in  abeyance.  Meantime,  in  itself 
and  its  specialities,  it  is  an  existence  quite  distinct  from  any  other 
hitherto  described,  at  least  so  far  as  I  have  noticed. 

I  am  myself  very  strongly  inclined  to  hold  by  the  view  that 
Sarcodic  existence  (at  least  those  of  the  fresh  waters),  that  is  "  Ehizo- 
poda,"  in  a  broad  sense,  embracing  various  types,  simple  as  they  are, 
are,  in  fact,  very  fixed  and  permanent  organisms.  Bound  up  with 
certain  "forms"  seem  to  be  their  own  inherent  specialities  of  structure 
and  of  texture,  their  peculiarities  of  temperament  (if  one  might  be 
allowed  to  use  the  word  in  relation  to  so  lowly  organisms),  their  idiosyn- 
crasies of  behaviour,  of  manner,  of  habit,  their  peculiarities  of  colour, 
or  its  changes,  their  greater,  or  less,  predilection  for  crude  "food,"  or 
seeming  total  abstinence.  Although,  indeed,  the  present  organism  cannot 
be  looked  upon  as  belonging  to  Ehizopoda,  it  is,  at  least,  not  less 
strongly  marked  than  any  of  the  not  very  numerous  but  yet  multifari- 
ous Sarcodic  existences  which  the  fresh  waters,  more  or  less  abundantly 
or  scantily,  offer  to  notice.  But  still  any  generic  or  specific  "  charac- 
ters" that  could  be  ascribed  to  it  would  seemingly  be  of  but  a  tem- 
porary or  artificial  nature,  pending  its  further  history.  Since  I  first 
met  with  it,  it  has  pertinaciously  refused  to  present  any  additional 

Zoe.  cit.,  T.  xix.,  f.  6  and  6. 


Archsr — Oil  Chlamydomyxa  Labyrinthuhides.  169 

particulars  as  to  its  deyelopment.  The  nearest  site  at  which  I  know 
it  to  occur  is  some  sixty  miles  from  Dublin;  but  I  am  inclined  to  sup- 
pose it  will  not  turn  out  to  be  very  uncommon;  and  at  other  seasons, 
or  other  localities,  to  other  observers,  it  may  unfold  more  of  its  history 
and  afiPord  further  data,  to  throw  a  light  on  its  true  nature. 

Ad  interim,  it  may  perhaps  be  well  to  epitomise  its  description, 
without  attempting  to  refer  it  to  any  special  class  or  order  for  the 
present,  under  the  name  of 

Chlamydomyxa  labyrinthuloides,  n.  g.  et  sp. 

Generic  eharaeters : — 

Body  substance  enclosed  in  a  multilaminated  cellulose  envelope^ 
whence,  through  an  apparently  lacerated  aperture,  the  non-nucleated 
granule-bearing  protoplasmic  contents  now  and  again  emerge,  irregu- 
larly giving  off  at  the  same  time  in  an  arborescent  manner  gradually 
tapering  ramifications^  and  emitting  numerous  extremely  slender 
hyaline  ramifying  threads  (^'filamentary  tracks"),  occasionally  coa- 
lescing and  forming  a  more  or  less  complex  **  lab3n^th,"  along  which 
proce^  from  the  central  mass  (as  from  a  reservoir)  numerous  little 
therein  pre-existent,  non-nucleated  globular,  but  plastic,  bodies,  which 
during  progression  assume  a  fusiform  figure  (''  spindles"). 

Specific  characters : — 

Very  variable  in  dimensions,  in  an  early  stage  endoparasitic,  that 
is,  living  within  the  tissues  of  aquatic  plants ;  general  mass,  with  or 
without  subdivision,  becoming  periodically  repeatedly  encysted;  en- 
veloping coat  hyaline,  glossy,  of  a  pale,  yellowish  colour,  when  viewed 
at  margin  (or  through  its  greatest  thickness) ;  remaining  thus  long 
dormant,  and  in  that  condition  the  '^  spindles"  globular;  pigment- 
granules  yellowish-green  or  bright  red,  rounded,  or  irregularly  shaped, 
very  dense;  now  and  again  putting  on  the  energetic  condition,  and 
forming  a  highly  ramified,  arborescent  structure,  the  central  mass  then 
presenting  numerous  rounded  pulsating  vacuoles;  the  "filamentary 
tracks"  extremely  slender,  quite  hyaline,  the  "spindles"  bluish  in 
colour,  homogeneous  in  appearance,  plastic,  their  progression  slow, 
gradual,  gliding ;  when  in  motion,  about  rcW  to  tt^tt  of  an  inch  in 
length,  and  about  half  as  broad. 


160  ProceedingB  of  the  Royal  Ir'uih  Academy, 


XX. — Lisrr  of  Seychelles  Mtktace-e,  with  DESCRimoys  of  two  New 
Species.  Bv  J.  G.  Baker,  F.  L.  S.  A>sistant  Curator  of  the  Kew 
Herbarium.'  (With  Plates  16  and  17.) 

[Head  February  8,  1875.] 

GenuB  EroENLi,  Linn, 

8ub-genuB  JossnriA. 

1.  E.  untflora,  Linn.  8p.  Plant  673,  E.  Michelii,  Lam.  D.  C.  Prod. 
8,  263,  Pliniapedunculata,  L.  fil.  Suppl.  253,  Bot.  Miig.  t.  473,  Steno- 
calyx  Michelii,  Berg.  A  native  of  Tropical  America,  now  widely 
naturalised  in  the  Old  World. 

8ub-genus  Stztghtic. 

2.  £.  Wrightii,  Baker,  PI.  16.  Branches  straight,  grey,  terete, 
moderately  stout.  Leaves  distant,  distinctly  stalked,  ovate  or  oblong, 
4-6  inches  long,  2^3  inches  broad,  cuspid£^,  broadly  rounded  at  the 
base,  rigidly  coriaceous,  shining,  with  the  veinlets  raised.  Cymes 
copious,  lax,  stalked,  lateral  and  terminal,  4-6  inches  broad,  with  as- 
cending main  branches.  Flowers  stalked  or  sessile.  Calyx  f-^  inch 
long,  narrowed  into  a  false  pedicel  in  the  lower  half  above  the  joiut ; 
lobes  twice  as  broad  as  deep ;  tube  not  produced  beyond  the  ovary. 
Petals  round,  J  inch  deep.  Stamens  and  style  J  inch  long.  Fruit  not 
seen.  Common  in  Mah^  and  Praslin.  Professor  Wright!  Some! 
Endemic. 

3.  E.  Sechell^xrumf  Baker,  PI.  17.  Branches  terete,  moderately  slender. 
Leaves  distant,  distinctly  stalked,  oblong,  acute  or  acuminate,  cuneate 
at  the  base  4-5  inches  long,  1^2  inches  broad,  rigid,  with  the  veinlets 
raised.  Cymes  short-stalked,  terminal  and  lateral,  3-4  inches  broad, 
with  spreading  main  branches ;  the  flowers  sessile  at  the  end  of  the 
brancMets.  Calyx  J  inch  deep,  turbinate,  as  if  narrowed  into  a  short 
pedicel  above  the  joint,  the  lobes  twice  as  broad  as  deep.  Expanded 
stamens  ^-f  inch  long. 

Seychelles,  described  from  a  specimen  in  the  herbarium  of  the  late 
Judge  Blackbume,  now  at  Kew.  Resembles  the  common  Asiatic  E, 
Jamhohna  in  lea!  and  general  habit,  but  differs  entirely  in  the  flowers. 
Endemic. 

Genus  Babeikgtonia,  Forst. 

Sub-genus  Butonica,  Juss. 

1 .  B.  speciosa,  L.  fil.  Seychelles  on  the  shores,  Bcger,  Home  I 
(Common  on  the  Mah^  side  of  Praslin.  Professor  Wright.)  Polynesia 
to  Comoros,  not  Continental  Africa. 

Sub-genus  Stravadium,  Juss, 

2.  B,  racetnosa,  Roxb.  Seychelles  on  the  shores,  Some!  Spread 
through  Tropical  Asia  and  Africa. 

3.  B,  acutangula,  Gaertn.  Seychelles,  Bqfer,     Tropical  Asia,  not 
.  Africa. 


KiNAHAN — On  Microscopical  Structure  of  Bocks.         161 


XXI. — ^Rkpobt  on  the  Micboscopicai.  Stbvctube  of  Rocks.     No.  2. 
By  G.  H.  KnTAHAir,  M.  R.  I.  A.,  &c.     (With  Plate  8.) 

[Read  February  8,  1875.] 

On  the  Quarh  contained  in  the  Granites  from  Knockanavaddy  {B^), 
Ballynahown  (^),  Furbo^h  (^  and  B'\  and  Kirkullen  (^),  County 
Galway, 

The  quartz  in  these  granites  occurs  principally  as  the  skeleton  of 
the  rocks ;  but  a  small  portion  is  found  as  inlying  blebs  and  crystals, 
principally  in  the  orthoclase.  The  latter  variety  is  very  similar  to  the 
quartz  blebs  so  characteristic  of  the  elvanytes  (PI.  8,  fig.  19). 

The  blebs  of  quartz  in  the  elvanyte  as  a  rule  are  in  crystalline 
forms,  or  coated  particles;  some,  however,  are  in  irregular  pieces, 
partaking  more  of  the  character  of  the  skeleton  quartz  of  typi- 
cal granite.  When  typical  they  have  sharp  outlines,  but  in  some 
the  margin  seems  to  graduate  quickly  into  the  surrounding  minerals. 
Many  of  them  contain  a  well-developed  complete  crystal  of  a 
foreign  mineral  (PI.  8,  fig.  19).  All  are  affected  more  or  less 
by  gas  specks  or  lahecuke.  These,  however,  as  a  rule,  are  not 
numerous ;  and  in  those  blebs  in  which  many  are  found,  the  quartz 
occurs  in  a  more  or  less  irregular  form.  Short  gas  tubes,  or  tuhulif 
seem  to  be  characteristic  of  the  quartz  of  the  elvanytes.  In  the  right- 
hand  quartz  crystal  (PI.  8,  fig.  19),  under  a  power  of  1 69,  very  few  laheetda 
appear,  nor  are  they  much  increased  in  number  under  a  power  of  386. 
In  the  left-hand  crystal,  under  a  power  of  169,  there  are  also  very  few 
labeculfe  to  be  seen;  but  under  llie  higher  power  (386),  about  double 
the  quantity  appears,  some  of  the  latter  being  so  small  as  to  be  scarcely 
visible,  while  in  two  places  they  form  short  strings  of  minute  beads. 
In  both  crystals  short  thick  tubuli  occur.  These,  under  a  power  of  196, 
appear  as  short  thick  lines ;  but  with  higher  powers  (from  250  to  400) 
they  are  seen  to  be  minute  tubuli,  probably  formed  by  gas.  Pig.  23, 
PI.  8,  represents  a  group  of  them  that  occurs  in  the  right-hand  crystal. 
The  two  sharp  cones  are  tubuli  which  lie  oblique  to  the  plane  of  the 
section.  Some  of  the  labeculse,  especially  most  of  those  that  are  com- 
plete spheres,  seem  to  be  gas  bubbles,  but  many  of  the  others, 
especially  those  that  are  oval  and  irregular  in  outline,  would  appear 
to  be  cross  sections  of  the  tubuli ;  their  different  shapes  being  due  to 
the  angles  at  which  the  tubuli  are  cut,  and  the  reflection  of  the  light 
against  the  walls  of  the  tubuli.  The  crystals  without  sharp  margin 
(left-hand  fig.  19,  PL  8)  usually  have  more  or  less  regular  fringes  of 
prismatic  colours. 

The  skeleton  quartz  in  the  granites  B',  B',  B',  and  B*  has  no 
crystalline  forms,  and  gives  a  gorgeous  change  of  colour  when 
the  polarizer    is  turned,    the  different  masses  of  colour  generally 


162  Proceedings  of  the  Royal  Irish  Academy. 

having  irregular  finely  serrated  thin  fringes  of  other  colour;  while 
some  have  the  irregular  lines  of  that  colour  running  through 
.them.  In  specimen  B*  very  little  quartz  appears  in  the  slice, 
while  in  specimens  B'  and  B**  the  fringes  are  very  marked,  and 
every  group  of  quartz  forms  a  patchwork  made  up  of  many  small 
irregular  portions.  In  the  granite  of  KirkuUen  (B*),  as  represented 
in  the  slice,  some  of  the  quartz  skeleton  seems  inclined  to  occur  in 
crystalline  forms,  and  in  pe^  to  partake  of  the  nature  of  the  quartz  of 
the  elvanytcs.  Its  quartz,  when  the  polarizer  is  turned,  is  inclined 
to  give  more  a  play  than  a  change  of  colours,  while  each  piece  usually 
has  a  fringe  of  prismatic  colours.  From  this  it  would  appear  that  the 
specimen  of  the  rock  was  taken  from  a  locality  in  which  the  rock  had 
lost  the  true  normal  character  of  typical  granite. 

Fig.  18,  pi.  8,  represents  two  small  masses  of  quartz  in  the  Kirkullon 
granite  magnified  to  42  diameters.  In  the  right-hand  one  a  crystal  will 
be  found  with  a  power  of  196  (see  fig.  20,  PI.  8).  In  it  are  numerous 
labeculffi,  some  lying  irregularly  about,  the  rest  more  or  less  in  lines  or 
zones ;  there  are  also  continuous  lines,  two  of  which  are  represented  in 
the  figure.  With  a  still  higher  power  (386),  these  lines  are  found  to  be 
strings  of  minute  beads,  apparently  along  shrinkage  or  fracture  fissures. 
With  the  high  power  we  also  find  that  in  places  the  labeculse  are 
systematically  arranged,  although  with  a  power  of  196  they  appear  to 
be  irregularly  grouped.  This  is  apparent  in  fig.  21,  PI.  8,  which  repre- 
sents the  place  marked  a  in  figure  20,  magnified  386  diameters,  and 
shows  there  at  least  three  distinct  systems  of  labeculse,  which  probably 
have  relations  with  different  facets  of  the  crystal.  The  higher  power 
also  explains  the  elongated,  pear-shaped,  small,  shaded  spots  in  figure 
20,  which  are  found  to  be  pointed  clouds  of  minute  labeculsB.  In  two 
places  at  the  margin  of  this  crystal  there  are  clouds  of  small  labecula;. 

The  left-hand  mass  of  quartz  (fig.  18,  PL  8)  is  different  from  that 
just  described,  as  the  labeculae  in  it  seem  to  be  irregularly  scattered 
about.  Associated  with  them  in  places  are  short  thick  lines,  few 
perfectly  straight  or  symmetrical,  like  those  in  the  quartz  of  the 
clvanyte  (fig.  23,  PL  8),  but  usually  more  or  less  curved  or  crooked, 
as  represented  in  fig.  22,  PL  8,  which  represents  the  place  marked  h 
in  fig.  18,  PL  8,  magnified  296  diameters.  There  is  also  a  peculiar 
feather-like  arrangement,  which  is  also  shown  in  fig.  22,  PL  8.  Under 
a  power  of  386  the  crooked  and  cufved  lines  are  found  to  be  gas  tubes 
or  tubulin  while  the  feather-like  arrangement  is  due  to  a  line  of  oval 
spots  which  are  the  oblique  sections  of  a  system  of  minute  tubuli. 
Five  of  these  tubuli  magnified  386  diameters  are  represented  below,  in 
figure  22,  PL  8. 

The  labeculae  in  the  quartz  are  rarely  visible  when  viewed  with  a 
less  power  than  50,  while  some  are  so  small  as  only  to  be  visible  with 
a  power  of  400.  A  crowd  of  labeculae  occur  at  some  of  the  margins  of 
the  masses  of  quartz,  while  the  irregular  lines,  seen  under  polarized 
light,  seem  to  mark  the  jxmotion  of  two  masses,  or  to  be  due  to  film 
filling  a  line  of  fracture.     In  the  quartz  of  B*  the  lubecula?  are  some- 


KiNAHAN — On  Microscopical  Structure  of  Bocks.         163 

times  in  lines,  but  more  usually  they  are  irregularly  scattered  about. 
A  well  marked  example  of  the  feather  arrangement  (fig.  22,  PI.  8)  was 
observed  in  one  place,  which  under  powers  ranging  from  300  to  400 
showed  distinctly  the  connection  between  this  appearance  and  a  system 
of  tubuli ;  the  feather  on  the  right  hand  being  the  oblique  longitudinal 
scKition  of  the  tubuli,  while  the  feather  to  £be  left  was  form^  by  re- 
flected light,  and  disappears  as  the  power  is  raised. 

In  the  quartz  of  B'  and  B^  some  pieces  have  the  labeculse  scattered 
about  as  in  the  quartz  of  B*,  and  in  them  the  tubuli  appear  to  be 
rare ;  but  in  most  of  the  others  the  labeculse  are  in  lines  or  systems, 
while  the  tubuli  are  not  uncommon.  These  tubuli  ai*e  usually  more 
or  less  curved  (fig.  22,  PL  8),  and  rarely  straight  and  symmetrical,  like 
the  tubuli  in  the  typical  quartz  of  the  elvanytes  (fig.  23,  PI.  8).  In  some 
of  this  quartz  there  are  thin  hair-like  or  capillary  lines,  not  visible  under 
a  power  of  230 ;  these  are  long  and  short,  straight  and  curved,  and 
cross  or  branch  from  one  another,  a  group  being  shown  in  fig.  24,  PI.  8. 
Some  of  these  capilloids,  under  powers  ranging  from  300  to  400,  are 
seen  to  be  tubuli,  while  the  nature  of  others,  especially  some  of  the 
long  ones,  may  be  different.  The  labeculee  associated  with  the 
capilloids,  as  shown  in  fig.  24,  usually  run  in  more  or  less  regular 
systems.  Some  of  these  labeculae,  as  previously  mentioned  in  describ- 
ing the  quartz  of  the  elvanyte,  are  undoubtedly  bubbles,  but  some  of 
them  represent  the  cross  section  of  the  tubuli,  the  larger  ones  being 
sections  of  the  short,  thick  tubuli,  and  the  minute  ones  the  sections  of 
the  capilloids. 

In  specimen  B*  a  few  of  the  pieces  of  quartz  give  a  play  instead 
of  a  chajage  of  colour. 

In  specimen  B*  the  non-crystalline  pieces  of  quartz,  the  labeculae  are 
very  similar,  and  similarly  arranged  to  those  in  the  skeleton  quartz  of 
specimen  B*.  Tubuli  are  usually  scarce;  those  principally  observed 
being  capilloid. 

The  inlying  blebs  and  secretions  of  quartz  found  in  the  felspars, 
but  principally  in  the  large  twin  crystals  of  orthoclase,  are  usually 
margined  with  a  prismatic  fringe,  apparently  due  to  a  minute  coated 
fitructure.  They  rarely  have  well  defined  margins,  but  usually 
graduate  quietly  into  the  envelope  of  felspar ;  many  of  them  have  a 
centre  or  nucleus  of  a  foreign  mineral.  They  contain  more  or  less 
labecidae,  some  being  full  of  them,  and  in  some  were  observed  the 
capiUoids  and  the  short  thick  tubuli. 


164  Proceedings  of  the  Royal  Irkh  Academy. 


XXII. — Report  on  the  Micboscopical  Steuctuee  of  Hocks.     No.  3. 
By  G.  H.  KiNAHAN,  M.  R.  I.  A.,  &c.,  &c. 

[Read  February  8,  1876.] 

Camsore  Granite^  Co,  Wexfard. 

The  granite  from  which  the  specimen  was  procured  occupies  a 
small  tract  on  the  S.  E.  shore  of  Wexford,  in  the  neighbourhood  of 
Camsore  Point.  The  mass  of  the  rock  is  evidently  of  metamorphic 
origin,  but  in  the  vicinity  of  the  Point  there  appears  to  be  an  intrusive 
mass  of  slightly  different  granite.  The  typical  rock  is  of  a  reddish 
greyish  colour,  containing  large  crystals,  usually  twins,  of  flesh- 
coloured  or  pink  felspar,  a  dull  white  felspar,  some  greenish  felspar,  two 
micas,  quartz,  and  pyrite.  Of  this  granite,  four  slices  were  prepared 
by  Mr.  Jordan,  of  the  Mining  Record  Office,  two  (B.  18  and  18*)  from 
a  block  of  granite  near  Castletown,  and  two  (B.  22  and  23)  from  the 
rock  at  Crossflntan  Point. 

B.  18.  This  slice  is  principally  occupied  by  one  of  the  large  crystals 
of  flesh-coloured  felspar.  In  the  slice,  the  minerals  observed  with  a 
power  of  17  are :  an  irregular  skeleton  of  quartz,  three  varieties  of 
felspar,  one  crystal  of  amphibole,  secretions  of 
mica,  and  a  few  opaque  crystals  (pyrite  ?). 
The  large  flesh-coloured  crystal,  which  is  pro- 
bably orthoclase,  has  a  lining  structure  that 
runs  obliquely  from  right  to  left  (see  woodcut), 
but  having  d^kly-shaded  portions  that  extend 
irregularly  from  left  to  right,  while  scattered 
over  it  are  numerous  secretions  of  quartz.  The 
second  felspar  [dull  white]  is  semiopaque,  but 
contains  numerous  iridescent  spots;  this  evi- 
dently is  a  variety  of  orthoclase,  and  probably  adularia.  The  third 
felspar  only  appears  in  small  crystals,  and  portions  of  crystals ;  it 
shows  minute  parallel  lines  of  prismatic  colours,  apparently  being  a 
triclinic  felspar. 

In  this  slice,  most  of  the  quartz  occurs  in  the  skeleton  of  the  rock  ; 
however,  a  few  particles  were  detected  in  irregular  crystalline  secre- 
tions, somewhat  like  the  quartz  characteristic  of  elvanyte.  The 
micas,  amphibole  and  pyrite  (?)  usually  occur  together,  forming 
irregular  nests;  they  are,  however,  sometimes  in  scattered  small 
patches,  while  a  few  individual  flakes  or  crystals  were  detected. 

B.  18*.  This  slice  seems  to  show  the  general  character  of  the  rock 
in  mass.  With  a  power  of  17  the  three  varieties  of  felspar  appear  to 
be  nearly  equally  developed.  The  quartz,  besides  forming  the  skele- 
ton of  the  rock,  appears  in  distinct  crystals,  while  associated  with  the 


KiNAHAN — On  Microscopical  Structure  of  Rocks.  165 

mica  and  pyrite  (?)  that  occur  in  nests,  is  a  bright  green,  beautifolly 
iridescent  minersd. 

B.  22.  This  slice  was  cut  from  a  specimen  taken  from  near  the 
margin  of  the  mass  of  the  granite,  where  it  is  slightly  foliated.  With 
a  power  of  17  the  three  yaricties  of  felspar  are  apparent.  The  flesh- 
coloured  yariety  shows  some  well-mark^  twin  crystals ;  the  iridescent 
semiopaque  felspar  is  only  sparingly  developed,  while  the  finely  lined 
felspar  crystals  are  well  marked,  this  latter  felspar  also  occurring  in 
some  places  as  thin  enyelopes  to  the  semiopaque  felspar.  Of  quartz 
there  is  a  large  proportion,  while  the  amphibole  is  in  excess  of  the 
micas ;  the  last  minerals  and  pyrite  (?)  occurring  in  minute  crystals 
and  flakes  scattered  about.  In  this  slice  was  also  obseryed  the  unde- 
termined bright  green  iridescent  mineral  found  in  B:  18*. 

B.  23.  This  slice  is  from  a  specimen  procured  a  little  north  of 
B.  22,  where  the  granite  is  distinctly  foliated.  With  a  power  of  17, 
quartz  is  found  to  be  the  most  abundEint  mineral,  a  large  proportion  of 
H  being  in  distinct  cirstals.  The  three  felspars  appear  to  be  nearly 
equally  deyeloped,  while  the  flakes  of  the  micas  are  minute  and  few. 
The  amphibole  is  in  small  nests,  or  scattered  ciystals,  while  the  pyrite 
is  in  most  minute  specks. 

It  should  be  mentioned  that  the  character  of  the  granite  at  Cross- 
fintan  is  porphyritic,  similar  to  the  rock  at  Camsore ;  and  that  the  two 
slices  [B.  22  and  23]  just  described,  were,  respectiyely,  cut  from  places 
that  seemed  to  show  the  general  arrangement  and  proportion  of  the 
different  minerals  to  one  another ;  as  always  in  the  vicinity  of  one  of 
the  large  felspar  crystals ;  the  other  constituents  of  the  rocks  seem 
to  have  a  peculiar  arrangement. 

From  these  notes  on  the  granite  of  Camsore,  it  will  appear  that  it 
and  the  Galway  granite  previously  reported  on  [Reports  Nos.  1  and  2, 
aHtea,  pp.  102,  161]  are  similarly  constitutea,  and  contain  nearl} 
identical  minerals.  Under  higher  powers  of  the  microscope,  it  wan 
found  that  the  individual  peculiarities  in  the  different  minerals  were 
very  similar  to  those  to  which  attention  was  directed  in  those  reports, 
no  remarkable  variation  having  been  observed.  It  is,  therefore^  un- 
necessary to  give  detailed  descriptions  of  them  again,  and  I  have  con- 
fined myself  to  the  general  character,  which  seems  to  identify  this 
granite  with  those  of  the  Galway  granite  type,  the  principal  constitu- 
ents being  three  felspars  [orthoclase,  adularia  (?),  and  oligoclase  (?)], 
quartz  (both  crystalline  and  as  the  skeleton  of  the  rock),  amphibole, 
pyrite,  and  locally  black  and  white  micas. 


R.  I.  A.  PROC,  SEB.  II.,  VOL.  II.,  SCIENCE. 


166  Proceedings  of  the  Royal  Irish  Acadefny. 


XUII. Oh  80MS  FUBTHXE   IltFEOYElCSNTS  OF  THE  CoMFABABLB  SeLF- 

BEOisisRDrG  Htgbomkekr.    Bj  M.  DoNOYAVy  Esq. 

[Bead  Febroary  8, 1875.] 

Whatetxr  length  of  gat-line  may  be  employed  in  giving  one  ronnd  of 
the  piimary  index,  an  equal  length  will  be  employed  in  giving  eyery 
other,  the  gat-line  being  eqaal  throughout ;  since  that  length  is  the 
natund  unit,  which,  divided  into  the  whole  gat-line,  gives  for  quotient 
the  number  of  rounds  which  the  primary  index,  under  the  circum'* 
stances,  is  capable  of  accomplishing.  The  ^iral  convolutions  of  the 
«trands  constituting  the  gut-line  act  simultaneously  in  all  its  parts, 
but  diminish  in  effect  from  the  bottom  towards  the  top.  Hence,  the 
shorter  the  intercepted  portion  of  the  gut-line  is,  the  less  of  the 
graduated  circle  will  be  traversed  by  either  index  in  a  given  time,  and 
the  greater  will  be  the  total  number  of  rounds  peif  ormed  by  the 
primary.  The  revolutions  of  the  primary  index  in  the  open  air, 
therefore,  virtually  divide  the  gut-line  into  as  many  parts  as  that 
index  performs  revolutions  round  the  graduated  circle ;  &e  intercept, 
or  what  is  the  same  thing,  its  effect  in  degrees  on  the  graduated  circle, 
being  the  natural  unit. 

According  to  the  expeiimente  of  competent  inquirers,  the  moisture 
of  the  atmosphere  and  of  pervious  bodies  can  be  completely  absorbed 
and  withdrawn  by  exposure  to  the  action  of  certain  exsiccants,  one  of 
the  most  efficient  of  which  is  chloride  of  calcium.  With  this  substance 
1  proceeded  as  follows: — The  hygrometer,  fitted  with  a  measured 
length  of  gut-line,  perfectly  dried  in  the  exsiccating  receiver  during 
three  days  by  means  of  ignited  chloride  of  calcium,  was  placed  in  an 
artificial  damp  atmosphere,  and  so  left  for  24  hours,  during  which  time 
the  primary  index  had  moved  very  nearly  nine  times  round,  and  had 
begun  to  move  backwards.  A  slip  of  wet  blotting-paper  being  intro^ 
duced  into  the  receiver,  the  index  continued  to  recede,  some  air  having 
entered ;  but  after  a  short  while  advanced,  and  at  length  reached  zero, 
thus  completing  ten  rounds,  shortly  after  which  it  permanently  ceased 
to  move.  Thus,  in  the  open  air,  ten  rounds  of  the  primary  index,  or 
one  of  the  secondary,  <!annot  be  exceeded,  for  they  comprise  all  the 
degrees  between  extreme  moisture  and  extreme  dryness.  The  length 
of  the  gut-line  exposed  to  the  action  of  the  exsiccant  being  4*65  inches, 
and  tlmt  of  the  intercept  '6  inch,  the  resulting  normal  number  of 
calculated  rounds  by  the  primary  index  would  be  7*75 ;  and  the  unit 
in  the  open  air,  at  this  rate,  woidd  be  by  calculation  12^-9.  But  the 
experiment  having  been  repeated  in  an  artificial  saturated  damp 
atmoephere,  the  gut-line  untwisted  to  ten  rounds  of  the  primary  index, 
which,  therefore,  gave  10°  as  the  unit;  and  the  average  of  the  differ- 
ences in  10  rounds  (viz.,  10, 10,  9,  10,  11,  8,  12, 10, 10,  10,)  gave  10°  as 


Donovan — On  the  Comparable  Self-regiatering  Hygrometer.  167 

the  unit  by  experiment.  ThuB|  calculation  and  experiment  agreed 
exactly. 

Should  it  happen,  through  any  cause,  that  ten  reyolutiona  of  the 
primary  index  do  not  measure  the  intercept  in  an  artificial  damp  atmo- 
sphere, a  new  revolution  will  commence.  When  the  secondary  indicates 
10°  in  the  open  air  (which  it  will  very  rarely  do),  we  say  that  the  air 
is  then  saturated ;  but  the  affinity  of  the  gut-line  for  water  may  not 
then  be  saturated.  In  an  artificiid  damp  atmosphere  the  gut-line  will 
still  absorb,  and  continue  to  turn  the  indexes  until  the  gut-line  be 
completely  soaked,  flaccid,  and  powerless. 

It  has  been  shown  in  my  former  communication*  to  the  Academy, 
that  a  gut-string,  as  obtained  from  the  music-seller,  always  contains 
water.  This,  being  not  water  of  composition,  but  hvgroscopic  moisture, 
may  be  abstracted  without  changing  the  nature  of  the  animal  matter 
that  contained  it.  It  obeys  the  law  of  the  instrument  with  regard  to 
absorption  and  expulsion.  The  indexes  show  how  much  had  been 
already  absorbed,  by  previous  exposure,  which  now  entering  undis- 
tinguishably  into  present  indications,  keeps  a  running  account  of  the 
tot^  water  previously  absorbed  or  newly  acquired. 


*  FitU  **  Proceedings  of  the  Boyfd  Irish  Academy,"  vol.  i.,  eer.  ii.,  pp.  476  and 
656. 


168  Proceedings  of  the  Royal  Iriah  Academy. 


XXIV. — Ok  two  NEW  Deposits  op  Human  and  other  Bones,  dis- 
oovEKED  IN  the  Catb  OP  DuNMOBE,  Co.  KILKENNY.  (With  Plate 
18.)  By  Edwabd  T.  Habdman,  F.  C.  S.,  F.E.G.  S.I.  (Of  the 
Geological  Survey  of  Ireland.) 

[Read  February  22,  1875.] 

The  Cave  of  Dunmore,  situated  about  six  miles  from  the  City  of 
Kilkenny,  has  been  from  very  early  times  an  object  of  much  interest, 
and  has  been  more  or  less  fully  described  by  various  writers,  the 
earliest  of  whom,  as  I  am  informed  by  the  Rev.  James  Qraves, 
M.  R.  I. A.,  was  Bishop  Berkeley.  After  him,  many  visitors  have  re- 
corded their  impressions  of  this  weird  locality,  but  the  fullest  account, 
which,  indeed,  like  Moses'  rod,  swallows  up  or  embodies  most 
of  the  rest,  is  that  of  Dr.  A.  W.  Foot,*  who,  in  1869,  explored 
the  place,  in  company  with  Rev.  Mr.  Graves  and  Mr.  Burtchaell,  C.  E. 
He  fully  describes  the  principal  features  of  the  Cave,  in  his  paper  read 
before  the  Royal  Historical  and  Archaeological  Association  of  Ireland, 
and  gives  an  account  of  a  quantity  of  human  bones,  which  were 
obtained  from  one  part  of  the  Cave.  I  shall,  therefore,  make  my 
descriptive  remarks  as  brief  as  possible,  as  they  must  necessarily,  in 
part,  be  a  repetition  of  that  and  other  papers.  Dr.  Foot  shows  that 
for  at  least  two  centuries  this  spot  has  been  known  to  be  a  receptacle 
of  numbers  of  human  bones,  which  were  said  to  have  strewed  the  floor 
of  it  abundantly;  but  in  modem  times  these  have  disappeared,  and 
Dr.  Foot's  collection  was  obtained  from  a  clay  or  silt  bed,  at  one  end 
of  the  Cave.  He  considers  the  bones  to  be  the  remains  of  natives 
slaughtered  by  the  Danish  invaders,  about  the  tenth  century.  It  is 
possible,  however,  that  they  belong  to  a  much  more  remote  antiquity. 
At  the  time  that  I  conceived  the  idea  of  examining  this  Cave  for 
animal  remains — ^in  the  course  of  my  duty  on  the  Geological  Survey — I 
was  quite  unaware  that  any  bones  had  ever  been  really  got  in  it, 
although  I  knew  there  was  a  local  rumour  that  some  of  those  con- 
cerned in  the  rising  of  '98  had  taken  refuge,  and  died  there.  I  was 
accompanied  by  Lieutenant  W.  W.  M.  Smith,  of  the  Royal  Artillery,  and 
it  fortunately  happened  that  we  picked  up  the  same  guides  who  had  con- 
ducted Dr.  Foot  and  his  party.  From  them  we  learned  of  the  find  of 
bones,  and  were  taken  to  the  spot,  whence  we  brought  away  many 
specimens.  No  other  bone  locality  was  then  known  to  these  men,  but 
on  a  subsequent  occasion  Mr.  Smith  and  I  visited  the  Cave  again,  and 


*  An  Account  of  a  visit  to  the  Cave  of  Dunmore,  Co.  Kilkenny,  with  some 
remarlu  on  Human  Remains  found  therein.  Bv  A.Wynne  Foot,  M.D.,  F.K.Q.C.P.I., 
Jour.  Roy.  Hist.  Archs&ol.  Assoc.  Ir.,  vol.  i.  (Fourth  Series),  Pt.  i.,  p.  66. 


Hardmax — On  two  new  Deposits  of  Human  Bones,       169 

found  at  quite  the  opposite  extremity  of  the  Cave,  and  in  a  different 
chamber,  two  places  in  which  bones  were  fully  as  abundant,  not 
onl^  human,  but  mixed  or  embedded  with  those  of  other  animids,  of 
which  those  of  sheep  or  goat,  pig  and  ox,  have  been  identified. 

To  make  my  account  intelligible,  a  short  description  of  the  Cave 
is  necessary.  The  mouth  of  the  Cave  (see  plan,  Plate  18,  fig.  1) 
which  forms  a  rude  arch,  some  30  feet  high,  and  about  equal  width,  is 
approached  from  an  old  quarry,  by  a  very  steep  incline,  continuing 
into  the  interior  some  distance  (about  200  feet).  At  the  bottom  it 
turns  ID  to  the  left,  and  is  at  last  stopped  'by  a  great  bank  of  stalag- 
mite, clay,  and  angular  debris.  This  place  is  the  lowest  part  of  the 
Cave,  and  is  called  the  "  Fairies'  Floor."  Eetracing  our  steps  about 
half-way  to  the  entrance,  there  is  found  a  deep  recess  in  tiie  side. 
Entering  this,'  it  is  seen  to  branch  to  the  north  and  south.  The 
northern  opening  is  narrow,  but  enlarges  after  a  little,  and  leads  into 
a  large  cluunber  of  very  irregular  height ;  in  one  place  the  floor  com- 
ing within  three  feet  of  the  roof.  This  is  known  as  the  ''Eabbit 
Burrow,"  and  at  the  extreme  end  of  it  (at  a)  is  the  deposit  of  bones 
referred  to  by  Dr  Foot.  The  southern  passage  leads,  by  a  very  rough 
and  difficult  way,  to  the  "  Market  Cross,"  a  very  large  chamber,  so 
called  from  the  magnificent  stalactitic  pillar  which  it  contains,  and  which 
is  represented  in  the  accompan3ring  sketch  (Plate  18,  fig.  2).  This 
ptQar  cannot  be  less  than  sixteen  feet  high ;  the  shaft  is  about  four  to 
five  feet  in  diameter,  the  pedestal  in  the  view  given,  frt>m  six  to 
eight  feet,  but  it  is  over  twelve  feet  when  looked  at  from  the  left, — ^the 
sketch,  in  fact,  showing  the  narrowest  aspect  of  the  whole  pillar.  A 
second  pillar,  of  nearly  the  same  dimensions,  formerly  graced  this 
apartment ;  but  I  am  informed  that  a  gentleman  in  the  neighbourhood 
committed  the  vandalism  of  cutting  it  down  to  adorn  Ins  grounds. 
The  examples  seen  in  this  part  of  the  Cave,  especially  that  before  us, 
exhibit  well  the  mode  of  formation  of  these  pillars,  and  their  gradual 
accumulation  from  ground  and  ceiling  simultaneously,  finally  meeting 
and  becoming  one  solid  mass,  then  thickening  laterally.  Near  this 
pillar  are  the  two  new  localities  for  bones  which  we  discovered.  As 
the  mode  of  occurrence  of  these  deposits,  and  of  that  already  known,  is 
similar  in  all  these  cases,  and  involves  points  not  touched  on  by  Dr. 
Foot,  I  shall  endeavour  to  describe  it.  I  should  first  remark  that  Br. 
Foot  and  his  friends  looked  on  these  deposits  entirely  from  an  anti* 
quarian  point  of  view;  and  most  naturally  so,  just  as  I  myself,  from  the 
nature  of  my  pursuits,  had  the  geological  ana  pre-historic  idea  upper- 
most in  my  mind  from  the  instant  I  saw  them :  and  in  support  of  those 
views  Dr.  Foot  quotes  from  the  Annals  of  the  Four  Masters  an  account 
of  a  great  slaughter  9i  Deare-Feama^  the  ''Cave  of  the  Alders,"  and 
which  he  considers  refers  to  the  Cave  itself.  I  am  inclined  to  think, 
however,  that  it  simply  denotes  the  townland,  or  territory,  so  called, 
according  to  the  usual  custom,  frt>m  the  principal  feature  in  it.  The 
passage  runs  thus,  the  date  being  the  Age  of  Christ,  928  : — 


170  Proceedings  qfthe  Royal  Irish  Academy. 

"  Oodfrej,  mndioii  of  Imhir,*  with  the  foreigiien  of  Ath-«I]ath,t  demoliahed 
and  plundered  Dearc-Fearna,  where  one  thonsand  pezaoDB  were  killed  in  this  year, 
as  ia  stated  in  the  following  quatrain : — 

'  Nine  hundred  years  without  kutow,  twenty-eight,  it  has  heen  prored. 
Since  Christ  came  to  our  relief,  to  the  plundering  (rf  Dearo-Feanuu*  *' 

O'Donovan,  in  a  note,  says  that  the  above  was  "probably  the 
ancient  name  of  the  Cave  of  Dunmore."  In  the  whole  passage  there 
is  no  reference  to  smoking  out,  or  ''  smothering/'  which  Br  Foot 
surmised  may  have  been  the  means  employed  in  reducing  the  garrison. 
The  Cave  was  certainly  not  '*  demolished,"  and  there  could  have  been 
but  little  to  plunder  it  of.  Moreover,  at  the  best  of  times  the  Cave 
could  hardly  accommodate  a  thousand  persons,  and  the  passage  appears 
to  me  to  apply  only  to  the  territory,  where  there  may  have  been  a 
large  village.  At  any  rate,  it  is  but  slender  evidence  on  which  to  refer 
the  bones  to  the  Danish  period ;  and  there  are  certain  circumstances 
that  seem  to  render  it  most  probable  that  these  bones,  even  if  not 
dating  from  one  of  the  Stone  Ages,  aro  of  much  greater  antiquity  than 
the  period  of  the  Danish  invasion.     These  I  shall  presently  rofer  to. 

At  Dr.  Foot's  locality  the  bones  occur  at  uie  base  of  a  steep 
declivity,  formed  of  a  quantity  of  silt,  sand,  and  clay,  which  rises  at 
a  sharp  angle  towards  the  roof,  which  it  meets.  This  stuff,  which  is 
covered  with  stalagmite  from  one  to  four  inches  thick,  is  well  stratified, 
and  was  undoubtedly  brought  in  by  water,  through  a  fissuro  at  the 
north  end,  now  filled  up.  The  following  is  the  section,  so  far  as  it 
could  be  dbserved  : — 

Sechov  at  Evn  of  Babbit  Bubbow.  % 

Ft  In. 

1.  Layer  of  stalagmite, 0  6 

2.  Fine  sand  stratified,  with  rib  of  infant, in  places,    0  6 

3.  Layer  of  stalagmite,  which  finally  unites  with  (1),  0  3 

4.  Sand, 0  3 

6.  Dark  carbonaceous  and  peaty-looking  matter,         . .     0    3 — 0  4 

6.  Sand, about    0    3 

7.  Fine  clav,  stratified, 0    4 

8.  Coarse,  loose,  brown  well-stratified  sand,  with  fragments 

of  decayed  bone, 2    6 

4  11 

The  main  deposit  of  bones  occurs  at  the  base  of  the  incline,  marked 
{a)  in  plan  and  section,  but  from  the  manner  in  which  it  has  been  dis- 
turbed, we  could  not  determine  their  exact  position.    From  the  method 


*  Annals  of  the  Four  Masters,  0* Donovan;  let  Division,  vol.  i.,  p.  623. 

t  Dublin. 

X  See  Sketch  Section,  Plate  18,  fig.  3.  Throughout  the  Cave  the  floor  is 
covered  with  large  blocks  of  limestone,  fallen  from  the  roof,  and  now  coated  thickly 
with  stalagmite. 


Hardmax — On  two  new  Deposits  of  Human  Bones.       171 

in  which  this  stratified  deposit  dips  away  from  where  it  and  the  roof 
come  together,  there  can  be  no  doubt  it  has  been  introduced  through 
an  old  opening  or  fissure  which  formerly  existed  here.  It,  with  the 
included  bones,  could  not  by  any  possibihty  have  been  brought  in  by  a 
stream  or  flood  of  winter  rain-water,  from  the  other  parts  of  the  Cave — 
as  Dr.  Foot  suggests,* — ^for  the  stratification  should  run  the  other  way, 
in  that  case,  and  the  Cave  should  be  nearly  filled  with  water  before  a 
stream  of  any  size  could  commence  to  flow  in  this  direction. 

The  bones  which  we  obtained  from  this  locality  are,  without  ex- 
ception, human,  and  are  mostly  in  a  fragmentary  condition,  owing  in 
great  measure  to  the  disturbance  which  the  soil  has  already  undergone. 
They  comprise  fragments  of  cranium,  lower  jaw,  with  teeth,  vertebrsB, 
humerus,  fibula,  ribs,  patella,  os  calcis,  &c.,  and  numerous  phalanges, 
which  seem  to  be  most  abundant.  It  is  sufficient  to  mention  the  fact 
of  all  these  being  human,  however,  for  Dr.  Foot,  in  the  valuable  paper 
cited,  gives  a  complete  list  of  all  the  bones  he  obtained,  numbering 
113  specimens.  Our  collection  from  this  place  numbers  about  70,  but 
some  of  these  may  be  only  difierent  parts  of  the  same  bone.  Yet,  it 
shows  what  a  quantity  oi  human  remains  lie  here.  One  fact  worth 
notice  is,  that  a  pre-molar  tooth  is  groxmd  down  to  a  flat  surface,  indica- 
tive of  the  owner  having  fed  on  grain,  which  had  been  ground  up  in 
some  such  rude  implement  as  a  quern,  and  thus  plentifully  mixed  with 
sand.  This  would  seem  to  point  to  an  earlier  period  than  the  tenth 
century,  when  the  Irish  x>eople  were  in  a  fair  state  of  civilisation.  I 
am  informed  by  Rev.  Mr.  Graves,  and  also  by  Professor  A.  Leith 
Adams,  F.  R.  S.,  that  such  teeth  are  not  uncommon  in  the  ancient 
Cakn-tombs  or  Kistvaens;  but  I  am  not  aware  if  they  have  been 
observed  in  more  modem  cases,  except  perhaps  in  those  of  some 
ancient  Egyptian  skulls. 

Another  point  must  not  be  passed  over,  viz.,  the  finding  of  bones 
in  the  silt  itself,  and  under  the  stalagmite  covering  it.  A  rib  of  a 
young  infant  was  found  by  us  in  the  layers  of  sand  six  inches  imder 
stalagmite,  and  near  the  old  opening,  and  consequently  at  a  higher 
level  in  the  Cave  than  the  maiu  deposit.  Then  in  bed  (8),  which 
comes  about  three  feet  beneath  the  stalagmite,  several  fragments  were 
found  in  a  stratified  layer,  which  appear  to  be  the  earthy  remains  of 
bone,  from  which  all  organic  matter  has  been  extracted.  Professors 
Macalister  and  A.  Leith  Adams,  who  kindly  examined  my  specimens, 
agree  with  me  that  some  at  least  of  these  are  bone. 

I  shall  now  refer  to  the  new  deposits  discovered  by  us  near  the 
''Market  Cross,"  at  quite  the  other  extremity  of  the  Cavern,  and  some 
600  feet  distant  from  the  last.  (See  plan,  Plate  18,  fig.  1,  b.)  These 
occur  in  precisely  the  same  way ;  that  is,  at  the  base  of,  and  inter- 
stratified  with,  silt,  clay,  and  sand,  which  have  come  in  through  old 
Openings,  now  entirely  closed  up. 


•  Op.  eit.y  p.  76. 


172  Proceedings  of  the  Royal  Irish  Academy, 

The  first  we  examined  forms  a  small  recess,  about  ten  yards  from 
the  ''  Market  Cross,"  and  to  tht)  left  of  the  approach  to  it.  We  had, 
in  fact,  made  this  visit  specially  to  make  a  survey,  in  order  to  de- 
termine where  fresh  explorations  might  be  best  made,  feeling  confident 
that  the  deposit  described  by  Dr.  Foot  was  but  one  of  many  in  this 
Cave;  and  anything  like  a  silt  bed,  or  old  opening,  received  our  principal 
attention.  This  recess  (fig.  4)  was  hidden  beneath  and  behind  large 
blocks  of  limestone,  but  well  repaid  our  search,  for  a  large  deposit  of 
bones  was  found;  and  nothing,  I  am  convinced,  but  proper  light,  tools 
and  labour,  was  requisite  to  enable  an  important  find  to  be  made.  The 
sloping  bed  was  encrusted  with  stalagmite ;  beneath,  and  encrusted  in 
which  are  numbers  of  bones,  not  only  human,  but  also  those  of  the 
lower  animals;  all,  however,  recent.  Some  of  those  are  encrusted 
thickly  with  stalagmite,  or  form  a  bone  breccia.  They  have  been 
identified  as  bones  of  sheep  (or  possibly  goat)  and  pig,  as  well  as 
human ;  the  latter  chiefly  those  of  very  young  children.  In  fact,  we 
hardly  obtained  a  single  bone  approaching  maturity  in  this  part  of  the 
Cave.  We  also  obtained  teeth  of  sheep  or  goats,  probably  the  former. 
The  dip  of  the  silt  bed  is  here  towards  the  north ;  just  the  reverse  of 
that  in  the  Babbit  Burrow. 

A  little  nearer  the  Market  Cross  we  come  to  another  mass  of  silt, 
&c.,  dipping  steeply  to  the  north-east.  It  appears  to  be  very  thick. 
The  hollow  at  llie  base  of  this  contains  quantities  of  bones,  both 
human  and  others.  We  have  obtained  the  lower  part  of  a  femur,  and 
also  a  cervical  vertebra  of  a  small  bovine  animal,  probably  a  calf, 
together  with  parts  of  the  human  skull,  and  other  bones.  Digging 
into  the  higher  part  of  the  bank  of  silt,  we  came  to  a  layer  of  fine 
mud,  or  clay,  containing  fragments  of  bones,  better  preserved  than 
those  found  under  precisely  similar  conditions  in  the  Babbit  Burrow, 
and  admitting  of  no  doubt  whatever  as  to  their  character.  As  they 
are  fragmentary,  and  much  decayed,  it  would  be  useless  to  make  out 
their  species. 

The  bones  we  got  from  here  have  been  determined  as  follows.  For 
assistance  in  the  identification  I  am  much  indebted  to  my  friend  and 
colleague,  Mr.  W.  H.  Baily,  F.G.S.  &  L.S.,  &c..  Palaeontologist  to  the 
Irish  Geological  Survey.  I  have  also  pleasure  in  acknowledging  the 
kindness  of  Dr.  John  Barker,  F.  B.  C.  8. 1.,  &c.,  who  allowed  us  to 
make  use  of  the  valuable  osteological  collection  in  the  Museum  of  the 
Boyal  College  of  Surgeons,  and  idso  gave  us  his  time  and  assistance  in 
comparing  the  specimens.  My  thanks  are  also  due  to  Professors 
Macaliater  and  A.  Leith  Adams,  who  confirmed  our  identification. 


HardmaK — (hi  two  new  Dqxmts  ofSuman  Bones,      173 


Other  Bones. 


Lm  OF  B0VB8  FBOM  ''  HaSUEI  CbOBS''  ChAMBZB,  DuiTMOBE. 

Suman. 

8Vall  and  Head,  &c.    1.  Temporal  and  tympanic  portion. 

„  2.        „  „  „  „       of  child. 

„  3.  Parietal.  „ 

,,  4,  5,  6.  Yarions  fragments  of  skull,  not  quite 

mature* 
„  7.  Basi-sphenoid  and  pre-sphenoid,  young  in- 

fant. 
,,  8.  Lower  maxillee,  with  canine  tooth  in  pre- 

eruptiye  condition,  very  young  infant, 
9,  10.  Tihulee  of  young  infant,  right  and  left. 
12,  13.  Femurs  of  very  young  child,  possibly 

new  horn. 
14-23.  Ribs  of  very  young  child  or  children. 

24.  Femur  of  older  child. 

25.  Os  calcis,  nearly  adult  (?). 
26-32.  Scapulae,  mostly  imperfect,  of  children  of 

various  ages. 

33.  Portion  of  rib,  adult. 

34.  ,,      ,,  tibia. 

35.  „      „  fibula. 

36.  „      ))  08  calcis,  young. 

38.  0&  calcxs,  adult,  left  foot, 

39,  40.  Masses  of  stalagmite  and  bone  breccia, 
with  various  fragments  of  skull, 
scapuIsD,  ftc. 


it 


Other  Animede. 

41.  Boa  (7  calf),  lower  end  of  femur. 

42.  „         „       second  cervical  vertebra. 

43.  Sua,  small  species,  upper  end  of  right  femur. 

44.  „     (larger  individual),  lower  end  of  femur. 

45.  46,  47.  Ovis  (?),  molars  (3). 
48»  Ovi»(?),  humerus,  lower  end  of  right. 
49.     ,,.       or  Capra  (?),.  metatarsal  set  upright  in 

stalagmite. 
„  50.     „  „      metatarsal,  set  in  stalagmite. 

MieeMamoue, — ^Various  pieces  of  bone  breccia,  or  limestone  cement- 
ed with  stalagmite,  and  containing  numerous  fragments  of  bone, 
tmdeterminable.  Also,  in  the  strat&ed  layers  of  silt)  nearly  decom* 
posed  fragments  of  bone. 


B.  I.  A*  PBGC.,  8B&.  n.*  TOU  n.,  8CIBNCB. 


2  A 


174  Proceedings  of  the  Royal  Irish  Academy, 

A  remarkable  fact  is  the  great  number  of  infantile  and  immature 
human  bones,  some  of  the  former  being  so  young  as  to  be  nearly  fo&tal. 
Those  of  the  pig  are  slightly  blackened,  as  if  by  fire.  Few  of  the 
bones  show  traces  of  haying  been  gnawed  by  wild  animals,  although 
on  some  are  marks  that  may  have  been  proauced  in  that  way.  Nor 
are  they  split,  as  if  for  the  extraction  of  marrow,  but  that  might  have 
been  accomplished  by  simply  cracking  them  across.  It  is  now  hard  to 
say  whether  they  were  broken  as  they  are  found,  by  accident  or  design. 

I  may  be  permitted  to  point  out  the  importance  of  this  find,  for 
more  than  one  reason.  First,  if  we  examine  the  literature  of  the  Cave, 
as  briefly  summarised  in  Br.  Foot's  paper,*  we  shall  find  that  all  the 
descriptions  of  the  locality,  where,  from  the  remotest  times,  bones 
were  known  to  occur,  refer  entirely  to  the  Eabbit  Burrow.  A  glance 
at  the  extracts  given  by  him  will  prove  that  at  once.  But  the  last 
expedition  before  Dr.  Foot's  was  undertaken  by  the  Bev.  Mr.  Graves, 
Mr.  Prim,  and  Mr.  William  Bobertson,  to  clear  up  doubts  expressed  by 
a  relative  of  the  latter  in  notes  of  a  visit  in  1819,  as  to  the  existence 
at  all,  in  the  Cave,  of  bones,  and  of  a  well  of  water.  These  gentlemen 
concluded  that  he  had  only  visited  the  ''Market  Cross"  chamber, 
where  fthey  considered)  no  bones  were  to  be  found,  and  came  to  the 
conclusion,  that  human  and  other  hones  are  confined  not  only  to  one 
chamber  J  hut  to  a  part  of  that  chamber  ^  and  in  the  immediate  vicinity  of 
the  weU,\  And  it  is  clear  that  all  the  observers  considered  the  bones 
to  have  remained  where  they  were  originally  deposited,  without  any 
reference  to  subsequent  geological  agencies. 

Besides  this,  the  discovery  of  these  bones  adds  another  'link  in  the 
chain  of  evidence  against  the  idea  that  all  the  bones  in  this  cavern  are 
those  of  persons  who  used  it  as  a  place  of  refuge  from  the  Banes,  and 
were  slain  there  in  the  tenth  century.  Along  with  the  improbability 
of  people  in  a  hurried  flight  taking  in  parts  of  animals  to  serve  as  food, 
and  of  their  eating  it  in  such  uncomfortable  and  out  of  the  way  positions, 
it  must  be  remembered  that  all  the  bones  occur  under  the  same  condi- 
tions, in  stratified  deposits,  under  clay  and  silt,  which  must  in  part 
have  come  in  later,  and  that  by  means  of  a  considerable  stream ;  nor 
could  they  have  been  introduced  from  other  parts  of  the  now  known 
interior  of  the  Cave,  as  the  stratification  runs  the  wrong  way  for 
this,^ind  in  a  direction  tending  towards  the  present  openings  of  the 
Cave. 

My  theory  is,  that  these  silt-beds  covered  with  stalagmite,  fill  up 
the  entrances  to  other  chambers  of  the  Cave  at  a  higher  level;  that  the 
bones  formerly  belonged  to  these  chambers,  and  have  been  brought  out 


*  Op,  eit.,  pp.  67-72. 

t  Kilkeimy  Arch»ological  Society  Proceedings,  Ap.  28, 1864.  See  Natural  History 
Review,  Vol.  I.,  p.  175.  The  italica  are  in  the  original.  Mr.  Bobertson  refers  to 
the  "large  fracture  wantonly  made  in  one  of  the  stalactitic  flutings  of  this  bold 
piUar  (*  ue  Market  Cross').  But  this  appearance  is  simply  caused  by  the  two 
portiona  of  the  pillar  not  having  yet  joined. 


Hardman — On  two  neto  Deposits  of  Human  Bones.      175 

to  their  present  position  by  water;  and  that  this  will  quite  account  for 
such  a  disproportionate  quantity  of  infants'  and  small  bones,  because 
naturally  we  should  expect  that  the  smallest,  and,  therefore,  the 
li^test  bones,  would  be  brought  down  in  largest  quantity. 

As  a  proof  of  the  pa8B%b%l%ty  of  such  upper  chambers  existing,  I 
shall  cite  the  case  of  the  "  Fairies'  Floor,"  which  Ues  to  the  north  of 
the  ''  Market  Cross"  chamber,  but  some  twenty  feet  below  it.  These 
are  connected  by  a  fissure  now  nearly  closed  up,  and  the  water  has 
brought  down  a  large  quantity  of  silt  and  debris,  covered  with  stalag- 
mite, in  every  respect  similar  to  the  bone  localities.  (See  Sketch, 
fig.  5.)    When  this  is  explored,  I  expect  it  will  also  yield  bones. 

The  manner  in  which  I  have  endeavoured  to  account  for  the  bone 
deposits  of  this  place  is  in  accordance  with  Schmerling's  and  Lyell's 
doctrine,*  that  cave-earth,  bone-breccias,  &c.,  are  produced  by  the 
sweeping  into  caves  or  fissures,  by  subterranean  streams,  of  quantities  of 
animal  remains,  together  with  finje  clay  and  sand.  There  can  be  no 
doubt  that  some  at  least  of  these  bones  form  part  of  a  stratified  deposit; 
but  whence  they  came,  or  to  what  period  they  belong,  are  points  which 
must  be  reserved,  until  further  examination  is  made  of  the  Cave; 
tills  I  hope  to  be  enabled  to  do  this  Summer. 

The  presence  of  the  bones  of  such  domesticated  animals  as  the 
sheep,  pig,  and  ox,  especially  the  first,  while  it  certainly  precludes  the 
T^erence  of  the  human  remains  to  a  very  remote  antiquity,  in  a 
geological  sense,  yet  allows  of  the  idea  that  they  may  belong  to  the 
Stone  or  Bronze  Ages.  Sheep  bones  have  been  found  along  with 
bronze  implements  in  Banish  peat  bogs  ;f  also  in  a  pre-historic  bury- 
ing-place,  or  cist,  at  Pickering,  England,  {  in  company  with  a  stone 
spear-head,  and  piece  of  pottery ;  and  are  frequency  met  with  in  the 
Swiss  lake-dwellings  of  the  later  Stone  period, §  as  well  as  a  small 
race  of  pig.  (It  may  be  mentioned  here  that  the  pig  bones  found  at 
Dunmore  are  either  very  young,  or  belong  to  a  small  species.)  In 
Ireland  itself,  in  the  Crannoge  of  Lagore,  bones  of  sheep,  goats,  oxen, 
swine,  &c.,  were  found  associated  with  antiquities  of  Stone,  Bronze, 
and  Iron  Ages,  under  sixteen  feet  of  bog.|| 

No  flint  implements,  works  of  art,  or  articles  of  domestic  use  have 
yet  been  found  in  Dunmore  Cave,  but  this  may  be  simply  because  they 
have  not  been  searched  for.  Mr.  Graves  told  me  he  had  not  looked  for 
any ;  and  although  Mr.  Smith  and  I  kept  a  look-out  for  anything  of 
that  kind,  our  time  was  too  short  to  do  more  than  lay  the  ground- 
work for  future  explorations;  and  as  the  bones  occurred  so  plentifully, 
they  kept  our  attention  fuUy  occupied.    On  the  other  hand,  were  these 


*  Principles  of  Geology,  Vol.  II.,  p.  521,  lOth  Ed.    Also  Antiqiiity  ot  Man. 

t  Antiquity  of  Man,  Lyell  (1863),  p.  16. 

i  Pre-hiatoric  Times,  Lubbock ;  Tables  of  Primary  Interments,  p.  97. 

f  Lyell,  op.  eit.,  p.  2d,  et  teg.    Also  Lubbock,  op.  eit.  p.  143. 

I  Lyell,  op.  eit.f  p.  30. 


176  Proceeding%  of  the  ttoyal  Irish  Academy, 

bones  so  recent,  as  hitherto  supposed,  it  might  be  imagined  that 
modem  implements,  arms,  &c.,  would  have  been  found  at  some  time  in 
the  Cave ;  but  none  are  recorded.  And  it  must  not  be  forgotten  that 
those  things  would  not  be  so  apt  to  escape  the  attention  ci  ordinary 
observers,  as  flint  weapons,  and  their  accompaniments,  which  such 
persons  would  be  most  likely  to  regard  as  mere  rubbish. 

Another  point  I  should  refer  to  is  the  presence  of  x>eaty  or  car- 
bonaceous matter  in  these  Gaves.  This  I  have  noticed  in  the  section 
of  the  Rabbit  Burrow.  It  has  also  been  mentioned  by  Br.  Foot*  as 
recorded  by  Mr.  Robert  Mallet  so  long  ago  as  1848,f  that  the  charcoal 
of  coniferous  Wood  was  found  in  layers  in  the  stalagmite.  Any  charcoal 
that  I  saw  was  remote  from  the  entrance,  and  interstratified  with  the 
deposit  in  which  the  bones  were  obtained ;  and  had  people  fled  there 
for  refuge,  and  been  undergoing  the  very  unpleasant  process  of  being 
'<  smoked  out,"  they  would  hardly  have  tried  to  add  to  their  discomfoii 
by  keeping  up  a  fire  in  the  interior.  So  that  if  it  were  even  conceded 
that  this  charcoal  was  the  result  of  fires  used  by  regular  denizena  of 
the  Cave,  that  would  be  sufficient  to  do  away  entirely  with  the  notion 
of  the  Danish  massacre. 

In  Mr.  Mallet's  paper,  just  cited,  the  occurrence  of  phosphate  of 
lime  in  the  stalagmite  of  this  Cave  is  shown,  fie  supposed  it  to  be 
derived  from  the  limestone  rocks  ^  but  it  is  most  probably  due  to  the 
presence  of  bones,  fie  does  net  seem  to  have  been  aware  of  their 
existence. 


*  Loc.  eit.,  pp.  79-80. 

t  Journal  Royal  Geolo^cal  Society,  Ireland,  Vol.  III.,  p.  362. 


/^       6^/c^^ 


Adams — On  a  Fossil  Saurian  Vertebra.  177 


XXV. — Oy  A  Fossil  SAuaiAw  Yeetebea,  Asctosattbtts  OsBomay 
PBOM  THE  Abctic  Eegions.  By  A.  Letth  Adams,  F.  E.  S.,  F.  G.  S., 
Professor  of  Zoology  in  the  Boyal  College  of  Science  for  Ireland. 

[Read  May  10, 1876.] 

The  vertebra  here  described  was  presented  to  the  late  Mr.  Salter, 
F.  G.  S.,  by  the  late  Admiral  Sherard  Osbom,  who  brought  it  from 
Bcndezvons  Point,  Byam  Martin  Channel,  in  the  Arctic  regions.  I 
lately  placed  myself  in  communication  with  Admiral  Osbom,  with 
the  view  of  obtaining  further  information  on  the  subject,  but  regret 
to  state  that  his  sudden  death  prevented  me  from  obtaining  whatever 
data  he  might  have  been  enabled  to  furnish  in  connexion  with  the 
history  of  its  discovery  and  the  conditions  under  which  it  was  found. 
However,  I  am  assured  by  the  Bev.  Dr.  Haughton  that  he  has  a  dis- 
tinct recollection  of  seeing  the  fossil  bone  when  in  the  possession  of 
Mr.  Salter,  and,  from  a  cursory  examination  at  the  time,  was  inclined 
to  think  that  it  might  have  belonged  to  Teleosaurus ;  at  the  same  time, 
he  informs  me  that  there  cannot  be  the  slightest  doubt  as  to  its  Arctic 
origin,  which  he  ascertained  previous  to  making  the  following  record, 
published  in  the  **  Appendix  to  the  Voyage  of  the  Fox,"  p.  372. 
Keferring  to  the  above,  and  remains  of  a  similar  description,  he  states : 
"Captain  Sherard  Osbom  also  found  broken  vertebrae  of  a  Teleosaurus, 
150  feet  up  Ecndezvous  Hill,  Byam  Martin  Channel,  at  the  north- 
west extremity  of  Bathurst  Island;  they  were  certainly  in  situ" 
Moreover,  according  to  the  determinations  of  this  distinguished  geolo- 
gist, it  will  be  observed  that  he  considers  the  upper  portion  of  BaQiurst 
Island  is  composed  of  carboniferous  limestone.* 

The  specimen  in  question  was  presented  by  Mr.  Salter  to  Dr.  Carte, 
F.  L.  8.,  Director  of  the  Natural  History  Museum,  Dublin,  who  has 
placed  it  in  my  hands  for  description. 

With  reference  to  other  discoveries  of  a  similar  nature  within  the 
Arctic  Circle,  it  may  be  stated  that  Sir  Edward  Belcher,  Sir  Leopold 
M'Clintock,  and  Admiral  Sherard  Osbom,  brought  many  fossils  from 
the  group  of  islands  lying  between  North  Cornwall  and  North  Devon. 
Among  others  wore  remaias  of  Ichthyosaurus,  determined  by  Pro- 
fessor Owen,  and  said  to  be  from  Lias  beds.f  These  are  the  only  Rep- 
tilian remains,  as  far  as  I  can  discover,  yet  described  as  Arctic  fossils. 

The  specimen  presents  the  following  mineralogical  characters,  for 
the  determination  of  which  I  am  indebted  to  my  friend  M.  Gages , 
M.  R.  I.  A. 


*  '' Geological  Acconntof  the  Arctic  Archipelago,  drawn  up  from  Specimens  col 
lected  by  Captain  F.  L,  M'Clintock,  R.  N.,  from  1849  to  1859,"  Jour,  of  the  Geo 
See.,  Dublin,  vol.  viiL,  p.  196.    By  the  Rev.  8.  Haughton,  F.  R.  S. 

t  Appendix  to  "  Last  of  the  Arctic  Voyages,"  by  Sir  E.  Belcher,  vol.  ii.,  p.  389 

B.  I.  A.  FROC,  8EB.  IL  YOL.  II.,  SaSNCl.  2  B 


178 


Proceedings  of  the  Royal  Irish  Academy. 


"  The  phosphate  of  lime  of  the  bone  has  not  been  entirely  removed 
by  the  process  of  mineralization.  There  are  incrustations  of  carbon- 
ate of  lime  in  patches  here  and  there,  and  it  covers  debris  of  quartz 
which,  with  numerous  cubic  crystals  of  iron  pyrites,  permeate  the 
cancellated  structure  wherever  the  outer  shining  vitreous  shell  has 
been  removed." 

The  following  portions  of  the  vertebra  are  deficient : — ^The  neural 
spine  is  broken  off  close  to  it^  base ;  there  is  a  loss  of  the  right  pre- 
and  portion  of  the  left  />o«^-zygapophysis,  together  with  a  eonsiderable 
portion  of  the  left  half  of  the  centrum.  The  outline  of  the  centrum 
was  evidently  ovoid.  There  is  a  distinct  cavity  in  front  (fig.  D),  and 
although  about  one-half  of  the  posterior  aspect  is  lost,  there  are  clear 
indications  {^g,  C),  of  a  similar  hollow,  thus  showing  an  amphicoelous 
structure. 


{Xatural  size,) 

It  will  be  observed  (fig.  A )  that  the  under  surface  of  the  elon- 
gated centrum  is  somewhat  arched,  the  anterior  portion  being  di- 
rected directly  forwards,  whilst  the  posterior  points  downwards  and 
forwards,  as  indicating  an  upward  neck  curvature.  The  lower  border 
of  the  centrum  has  been  considerably  injured  laterally,  but  clearly  it 
was  narrow,  and  not  broad  and  rounded.  On  its  ^side  there  is  a  deep 
sulcus,  pressed  inwards. 

The  dia-  and^rirfl-pophyses,  so  pronounced  on  the  vertebra  of  Croco- 


Adams — On  a  Fossil  Saurian  Vertebra.  179 

dilia,  and  also  the  traces  of  the  neuro-central  suture,  so  generally  present 
in  this  order,  are,  unfortunately,  as  regards  the  tubercula  and  capi- 
tula,  undeterminable,  from  injuries  to  the  outer  shell ;  a  crack,  how- 
eyer,  in  the  situation  of  the  neuro-central  suture  may  indicate  the  line 
of  junction. 

The  ^tf-zygapophysis  (fig.  A),  is  produced  with  a  deep  itU&r  zyga- 
pophysiid  pit  (figs.  B  and  B).  The  articulating  surface  is  oval  and 
plane,  and  the  angle  of  inclmation  between  it  and  the  other  is  50^ : 
a  still  wider  and  deeper  cleft  intervenes  between  the  posterior  zyga- 
pophyses  fig.  (C).  Both  of  the  pits  indicate  powerful  nuchal  liga- 
ments. 

The  base  of  the  neural  spine  is  compressed,  and  presents  a  hollow 
on  either  side  (figs.  A  and  B),  with  prominent  ridges,  which  go  to 
form  the  outer  border  of  the  /M)«f-2ygapophyses.  The  latter  are  nearly 
horizontal  (fig.  C).  In  all  these  characters — ^to  wit,  the  hollow  at  the 
base  of  the  spine,  zygapophysial  ridge  and  posterior  articular  surface — 
it  seems  to  agree  with  Lacertilia  rather  than  Crocodilia.  The  cervical 
neural  spine  in  Crocodilia  is  lengthened,  and  tapers  towards  a  blunt 
point ;  whereas  in  LacertiUa  it  is  shorter  and  broader  in  the  antero- 
posterior direction,  which,  judging  from  the  extent  of  the  fractured 
surface  (fig.  B),  was  apparency  the  case  also  in  the  fossil.  The 
neural  canal  is  small  and  oval.  Further  there  do  not  appear  to  me  any 
points  worthy  of  record. 

I  conceive  that  the  bone  may  in  all  probability  have  been  one  of 
the  middle  cervicals  of  a  Saurian,  with  bi-concave  vertebrae.  Com- 
pared with  recent  and  fossil  species  of  Beptilia,  the  above  represents 
an  animal  between  ten  and  twelve  feet  in  length.  Seemingly 
remarkable  contrasts  between  the  above  and  cervical  vertebrae  of  Teleo- 
saurus  and  other  mesozoic  crocodiles  are  in  the  produced  /^^-zygapo- 
physis,  sub-oval  centrum,  and  the  small  size  of  the  latter,  as  compared 
with  tiiie  rest  of  the  bone — ^to  wit,  height  of  the  arches  and  massive 
ligamentous  and  zygapophysial  attachments  of  this  Arctic  fossil,  which 
would  appear,  moreover,  to  represent  a  considerably  smaller  species  than 
either  TeUosaurus  brevidens,  T.  cadoiMrm's,  or  T,  hubulid&ru.  The  charac- 
ters being  narrowed  to  a  few  points  in  connexion  with  a  single  imper- 
fect vertebra,  I  feel  that  it  would  be  impossible  to  establish  reliable 
comparisons  between  it  and  fossil  genera  of  the  Mesozoic  formations. 

It  is  to  be  regretted  that,  owing  to  the  untimely  death  of  Admiral 
Osbom,  I  have  been  unable  to  obtmn  further  evidence  as  to  its  history. 
Admitting,  however,  its  Arctic  origin,  as  given  by  the  late  eminent 
palaeontologist  Mr.  Salter,  I  propose  for  it  the  provisional  name  of 
Aretosaurus  08hamt\  in  respect  for  the  memory  of  this  distinguished 
traveller,  and  in  hopes  that  the  naturalists  of  the  expedition  now  about 
proceeding  to  the  Arctic  Eegions  will  be  enabled  to  verify  these  few 
data  by  fresh  discoveries  of  a  similar  description. 


180 


Proceedings  of  the  Royal  Irish  Academy. 


XIVI. — Ingeitite    Bocks.      Report  No,  4. 
M.  R.  I.  A.,  &c.,  &c. 

[Read  May  10, 1876.] 


By  G.  H.  En^A^Aif , 


liONQSTOKE,  Co.  Tippcrary,  Ordnance  Sheet  58. — ^An  intrusive  mass, 
coming  up  through  the  lower-bedded  carboniferous  limestone.  This 
granitic  rock  is  a  more  or  less  granular  elvanyte,  which  may  be  thus 
described : — a  slightly  granular  purplish  brown  color,  weathering  to  a 
dirty  reddish  or  orange.  The  base  contains  crystals  of  yellowish-greenish 
felspar,  some  small  blebs  of  quartz,  nests  of  minute  greeni^  flakes 
(mica?),  which  congregate  in  a  matrix  that  weathers  ferruginous.  In 
this  protrusion  there  has  not  been  a  deep  quarry  opened,  and,  as  the 
rock  IS  more  or  less  weathered  to  a  depth  of  oyer  twenty  feet,  it  is  im- 
possible to  procure  a  normal  specimen  of  the  rock,  and,  as  may  be 
expected,  the  slices  cut  are  unsatisfactory,  as  the  minerals  they  con- 
tain are  more  or  less  affected  by  rust  stains.  Under  a  power  of  33  the 
rock  seems  to  have  a  brownish  felspathic  matrix,  containing  numerous 
black,  opaque,  ill-defined  crystals ;  and  the  latter,  under  a  high  power 
(327),  are  found  to  be  crystals  of  pyrite  changed  on  the  edges  into 
rust.  In  the  matrix  also  are  found  numerous  specks  and  small  se- 
cretions of  quartz  ;  the  latter,  under  a  power  of  258,  are  found  to  be 
arranged  somewhat  similar  to  what  is  shown  in  figs.  1  &  2,  where  the 
unshaded  portions  are  the  quartz ;  the  obliquely-shaded  portions,  the 
felspathic  matrix;  the  long  crystals,  appear  to  be  amphibole,  while 
there  are  bunches,  or  individual  crystals  (some  well-marked  octohe- 
drons),  of  pyrite,  or  perhaps  of  a  fernferous  garnet. 


Fig.  1. 


Fig.  2. 


The  mass  of  the  quartz  evidently  has  crystallized  out  after  the 
other  minerals,  as  it  is  found  filling  up  the  vacancies.  In  it  were  re- 
marked lines,  groups  and  scattered  minute  air  bubbles,  and  some  tubuli; 
in  the  sections  examined  they  were  not  very  numerous.  In  one  piece 
of  quartz  forming  a  triangle  (fig.  2),  the  plane  is  traversed  by  nume- 
rous irregular  lines,  giving  the  crystal  a  ruptured  aspect  (fig.  4) ;  but 


KiNAHA^ — On  Ingenite  Rocks. 


181 


under  a  fayonrable  light  they  are  found  to  be  irregular  minute  black 
tubuli — some  being  gtraight,  others  curved,  some  oblique  to  or  at  right 
angles  to  one  another,  while  some  are  short  and  others  long.  At  the 
apex  of  the  triangle  there  are  a  few  air  bubbles,  but  in  the  rest  of  it 
only  one  was  detected. 

The  felspathic  base,  under  a  power  of  386,  shows  a  greenish-brown 
ground,  thickly  covered  over  with  whitish  dots,  lines,  and  broken 
lines  which  are  irregularly  mixed  up  together ;  while  in  many  places 
in  it  there  are  incipient  forms,  as  if  different  minerals  had  attempted 
to  crystallize  out.  It  is  also  found  to  be  principally  a  mixture  of  two 
felspars,  one  semi-opaque  with  irridescent  spots,  the  other  having  a 
parallel  play  of  colours  ;  these  seem  to  be  most  irregularly  combined, 
but  the  latter  apparently  predominates. 

The  felspar  crystals  developed  in  the  matrix  seem  all  to  have  ill- 
defined  margins.  The  most  perfect  seen  in  the  slices  is  a  twin  crys- 
tal (fig.  3).  Of  these  the  left-hand  member  has  an  imperfect  ribaned 
structure  parallel  to  the  long  axis  of  the  crystal ;  while  in  the  right- 
hand  crystd  there  is  an  obscure  oblique  structure.  In  all  the  crys- 
tals of  this  felspar  there  are  inlying  opaque  black  specks,  probably  of 
pyrite ;  the  large  black  speck  figured  near  the  bottom  of  the  left-hand 
crystal  (fig.  8)  seems  to  be  a  perfect  hexahedron. 

Besides  the  more  or  less  regular  crystals  of  felspar,  there  are  ir- . 
regular  secretions,  which  consist  in  part  of  a  semi-opaque  irridescent 
felspar  {a,  fig.  6),  containing,  what  seems  to  be  nuclei,  irregularly-shaped 
masses,  (h)  of  a  felspar,  in  which  is  a  play  of  colours  in  parallel  lines, 
similar  to  that  displayed  by  a  section  of  labradorite ;  while  scattered 
about  in  the  felspathic  matrix  are  more  or  less  well-formed  small 
crystals  (c),  apparently  of  the  same  felspar  as  the  first-mentioned 
nucleus. 


Fig.  3. 


Fig.  4. 


Two  of  the  nests  of  greenish  flakes,  when  magnified  to  33  dia- 
meters, are  figured  (fig.  5).  With  a  power  of  385,  the  uppermost  of 
these  nests  is  found  to  be  fringed  by  fiaky  crystals  of  an  olive-green 
mineral,  while  the  central  portion  is  principally  crystals  of  pyrite  (?), 
with  which  are  associated  the  olive-green  mineral.  In  the  oblique 
lower  nest  the  olive-green  mineral  and  the  pyrite  (?)  are  irregularly 


182 


Proceedings  of  the  Royal  Irish  Academy, 


combined;  but  at  the  apex  there  is  a  great  predozninance  of  the 
pyrite. 


Fig.  5. 


Fig.  6. 


From  the  slices  examined,  the  peculiarities  of  this  elvanyte  seem  to 
be  the  nearly  total  absence  of  mica,  except  in  nests,  while  the  crystals 
or  blebs  of  quartz,  so  characteristic  in  general  of  elvanytes,  are  nearly 
microscopic.  The  incipient  crystalline  forms  in  the  felspathic  matrix 
are  also  remarkable.  But,  as  before  mentioned,  the  specimens  ob- 
tained were  more  or  less  weathered,  and  taken  from  near  the  margin  of 
the  mass.  If,  however,  normal  specimens  could  have  been  procured, 
and  from  places  more  deeply  seated,  it  is  probable  that  the  porphyritic 
characters  would  be  better  developed. 


Davy — On  Properties  possessed  hy  Salts  ofFulminic  Acid.  183 


XXYII. — On  some  hewly  obsebtxd  Phopeeties  possessed  by  certain 
Salts  of  Fuuonic  Acid.  By  Edmund  W.  Davy,  A.  M.,  M.  D.,  Pro- 
fessor of  Forensic  Medicine,  Eoyal  College  of  Surgeons,  Ireland. 

[Bead  January  11, 1875.] 

The  salts  of  folminic  acid,  or  the  fulminates,  have  not  received  the 
attention  which  the  interest  arising  from  their  extraordinary  proper- 
ties would  lead  us  to  expect.  This  is,  no  doubt,  due  in  a  great  mea- 
sure to  their  being  such  highly  explosive  and  consequently  dangerous 
compounds,  which  have  already  occasioned  several  serious  and  even 
fatal  accidents  to  individuals  whilst  making  them  objects  of  research  ; 
they  are,  therefore,  considering  the  amount  of  personal  danger  attend- 
ant on  a  study  of  their  properties,  not  very  inviting  subjects  of 
inquiry,  and  necessitate  the  exercise  of  much  caution  on  the  part  of 
those  engaged  in  their  investigation. 

The  compound  which  is  known  to  chemists  under  the  name  of  ful- 
minic  acid,  and  which  is  expressed  by  the  empirical  formula  HjCaNjOj, 
though  it  has  never  yet  been  isolated  or  obtained  in  the  free  state,  is 
capable,  as  is  well  known,  of  forming  a  number  of  simple  and  com- 
pound salts,  which  are  endowed  with  more  or  less  explosive  proper- 
ties. Of  those  salts,  by  far  the  most  important  is  the  fulminate  of 
mercury,  which  constitutes,  as  is  well  known,  tho  active  constituent 
of  the  percussion  caps,  and  of  the  detonating  matters  which  are  used  to 
fire  the  charges  in  our  guns  and  pieces  of  ordnance ;  and  for  those 
purposes  it  is  now  manufactured  in  large  quantities,  and  forms  a  very 
important  instrument  of  modem  warfare,  since  by  its  employment  the 
use  of  flint  and  steel,  matches,  and  other  rude  means  of  finng  small  and 
large  guns  have  been  quite  abandoned,  at  least  among  all  civilized 
nations. 

Whilst  making  some  experiments  on  the  fulminate  of  mercury,  I 
observed  that  when  that  salt  and  the  f errocyanidc  of  potassium,  both 
in  aqueous  solution,  are  gently  heated  together,  the  mixture  at  first 
acquires  a  faint  reddish  yellow  tint,  which  quickly  passes  into  a  port- 
wine  or  deep  purple  colour,  without  the  separation  apparently,  at 
least  at  first,  of  any  gas  or  solid  matter.  The  development  of  this 
coloration,  under  the  circumstances  stated,  being  considered  very 
singular,  and  hitherto  unnoticed  (as  far  as  I  have  been  able  to  ascer- 
tain), led  me  to  study  the  matter  more  closely,  to  determine  the  nature 
of  this  coloured  compound,  and  of  the  changes  taking  place  in  its  for- 
mation. 

On  prosecuting  this  inquiry,  I  further  ascertained  that  when  the 
purple  compound  was  fully  developed,  if  the  heat  was  continued  for 
some  time,  or  more  quickly  if  the  temperature  was  raised  to,  and 
maintained  at  the  boiling  point,  the  purple  colour  gradually  dis- 
appeared, the  liquid  acquiring  a  light  yellow  tint,  whilst  more  and 
more  of  a  reddish  brown  solid  matter  (which  was  ascertained  to  be  the 


184  Proceedings  of  the  Royal  Irish  Academy. 

peroxide  of  iron)  was  produced ;  these  changes  being  accompanied  by 
the  evolution  of  more  or  less  of  ammonia,  and  by  the  mixture,  which 
was  at  first  quite  neutral,  acquiring  a  strong  alkaline  reaction.  The 
solution  being  filtered,  and  concentrated  by  evaporation,  was  found  to 
yield  small  prismatic  crystals  of  a  colourless  or  very  light  yellow  salt, 
which  appears  to  be  a  double  cyanide  of  potassium  and  mercury. 

Considering  that  the  principal  feature  of  interest  in  the  reaction  of 
the  fulminate  on  the  ferrocyanide  was  the  formation  of  the  purple 
compound,  my  attention  was  chiefly  directed  to  its  investigation.  But 
I  soon  ascertained  that  this  compound  was  a  substance  of  a  very 
unstable  character,  and  that  it  present^^d  great  difficulties  in  the  way 
of  its  separation  from  the  matters  with  which  it  was  associated,  as 
procured  in  the  reaction  referred  to ;  and  not  being  able  to  obtain  it  in 
a  pure  or  suitable  state  to  submit  it  to  actual  analysis,  I  was  for  a 
considerable  time  unable  to  obtain  any  clue  as  to  its  real  nature,  fur- 
ther than  it  was  some  organic  compound  of  iron,  in  which  cyanogen, 
or  at  least  its  elements,  were  constituents. 

At  last  it  occurred  to  mc,  that  the  coloration  observed  might 
be  in  some  measure  connected  with  the  formation  of  the  fulminate 
of  iron ;  and  on  making  some  of  that  salt,  and  comparing  its  reac- 
tions with  tho5e  of  the  compound  referred  to,  many  points  of  agree- 
ment between  them  were  at  once  perceptible.  I  may  observe  that 
the  fulminate-  of  iron  is  readily  obtained  by  the  action  of  metallic 
iron  on  the  fulminate  of  mercury,  suspended  in  water.  Thus  if  about 
equal  bulks  of  the  fulminate  and  of  fine  iron .  filings  are  placed  in 
a  small  stoppered  bottle,  which  is  then  filled  with  distilled  water, 
and  being  closed  is  occasionally  agitated,  the  liquid  in  a  short  time 
acquires  a  yellowish  tint,  which  gradually  deepens  in  colour,  whilst 
the  filings  become  tarnished,  and  more  or  less  of  mercury,  in  the 
form  of  minute  globules,  make  their  appearance.  After  a  few  hours 
the  decomposition  of  the  fulminate  of  mercury  will  be  more  or  less 
complete,  and  on  filtering  the  mixture,  a  dull  yellow  liquid  is  obtained, 
which  holds  the  fulminate  of  iron  in  solution.  This  fulminate,  as  so 
obtained,  was  described  by  my  late  father,  amongst  several  other  com- 
pounds of  fulminic  acid,  which  he  was,  I  believe,  the  first  to  discover, 
during  his  elaborate  researches  on  that  acid.  This  salt  was  observed 
by  him  to  produce,  when  treated  with  diluted  acids,  a  fine  red  or  purple 
colour,  which  disappeared  after  some  time,  evolving  hydrocyanic  acid 
amongst  other  products.  He  also  found  that  a  somewhat  similar 
colour,  rapidly  changing  to  a  bluish  black,  with  a  precipitate  of  that 
colour,  was  developed  on  heating  this  fulminate. 

But  this  development  of  colour  only  occurs  in  the  case  of  the  freshly 
prepared  fulminate  of  iron,  for  the  salt,  being  one  of  very  great  insta- 
bility, commences  almost  immediately  after  its  formation  to  undergo 
spontaneous  changes,  which  are  attended  by  the  separation  of  a  dark 
brown  substance,  even  when  the  solution  is  kept  excluded  from  the 
air  in  a  well-stoppered  bottle  ;  and  after  such  changes  have  taken  place, 
it  ceases  to  develop,  either  by  the  action  of  acids  or  by  heat,  the  colo- 


Davy — On  Properties  possessed  by  Salts  of  tktlminic  AckL  186 

ration  just  stated.  Mj  father  also  observed  that  alkalies  produced  in 
freshly  prepared  fuhnmate  of  iron  a  dull  green  precipitate,  quickly 
changing. to  a  brown  colour,  which  is  obriously  due  to  the  separation 
of  iron  as  an  oxide  from  the  fulminate  of  iron.  And  I  have  myself 
observed  that  the  light  yellow  liquid  which  remains  after  the  action  of 
the  alkaUes  and  the  separation  of  the  oxide,  at  once  develops  a  fine 
port-wine  colour,  when  it  is  treated  with  diluted  acids,  and  that  the 
coloration  so  produced  is  much  more  stable  than  that  developed  by 
directly  treating  the  fulminate  of  iron  similarly  ;  aud  that  this  red  or 
purple-coloured  compound  resembles  in  all  its  characters  that  produced 
in  the  new  reaction  of  the  ferrocyanide  on  the  fulminate  of  mercury 
already  referred  to. 

As  to  the  singular  development  of  colour  when  the  fulminate  of  iron 
is  treated  with  dilute  acids,  I  am  not  aware  that  any  explanation  has  as 
yet  been  given ;  and  the  one  that  I  wouldnow  suggest  accounts  for  its  pro- 
duction, not  only  in  the  case  of  the  fulminate  of  iron,  but  also  in  the  new 
reactions  which  I  have  myself  recently  observed ;  and  explains  some  of 
the  properties  of  this  curious  purple-coloured  compound.  To  make 
the  explanation  I  would  offer  intelligible,  I  should  first  observe  that 
fulminic  acid  is  generally  regarded  as  a  bibasic  acid,  which  is  capable 
of  forming  two  classes  of  salts,  viz.,  the  neutral  and  the  acid  salts.  In 
the  first,  the  two  atoms  of  hydrogen  in  the  hydrated  acid  (HjCaNsOs), 
are  replaced  either  by  two  atoms  of  a  monad  metal,  as  in  the  case 
of  the  fulminate  of  silver  (AgjCaN^O,),  or  by  one  atom  of  a  dyad 
metal,  as  in  the  fulminate  of  mercury  (HgCfl^aOa).  In  the  second  class 
we  have  either  one  atom  of  hydrogen  stiU.  retained,  whilst  the  other  is 
replaced  by  a  monad  metal,  as  in  the  case  of  the  acid  fulminate  of 
silver  (AgHCaN^Oa),  or  two  atoms  of  hydrogen  are  retained  (the  mole- 
cule of  fulminic  acid  being  doubled)  where  a  dyad  metal  occurs,  as 
in  the  acid  fulminate  of  mercury  (HgH>  (CgNjOa)').  Now  as  iron 
in  most  of  its  combinations  plays  the  part  of  a  dyad,  we  should  express 
its  neutral  fulminate  thus,  Fe  Cal^aOa ;  and  when  this  salt  is  treated 
with  a  diluted  acid  there  is  formed,  as  I  conceive,  an  acid  fulminate  of 
iron  (a  hitherto  undescribed  salt),  by  the  following  reaction,  where  for 
example,  sulphuric  acid  has  been  employed,  2  Fe  CjNaOa  +  H2S04  =  Fe 
Ha  (CaNjOj)'  +  Fe  SO4,  and  that  it  is  this  acid  fulminate  which  pos- 
sesses the  red  or  purple  colour,  whilst  it  is  at  the, same  time  much 
more  stable  or  less  prone  to  decompose  than  the  neutral  salt.  If  this 
acid  fulminate  is  treated  with  an  alkali,  its  purple  colour  disappears, 
owing,  as  I  conceive,  to  the  formation  of  a  neutral  double  fulminate  of 
iron  and  the  metal  of  the  alkali,  which  is  a  colourless  salt  in  dilute 
solution ;  thus  in  the  case  of  potash  being  added  to  the  acid  fulminate 
of  iron,  there  would  be  a  double  neutral  fulminate  of  iron  and  potas- 
sium formed,  according  to  the  following  reaction :  Fe  H,  (0,1^,0,)'  +  2 
KHO  =  Fe  K,  (CjN,0,)  *  +  2  H3O,  and  this  colourless  solution  being 
treated  with  a  diluted  acid  again  develops  the  purple  colour  by  the 
reformation  of  the  acid  fulminate,  as  the  following  equation  indicates : 
Fe  Ka  (Calf,Oa)»  +  HaSO^ «  Fe  H,  (CaNaOa)'  +  KaSO*.    Or  again,  if  to 

B.  Z.  A.  FSOC,  SBB.  II.,  VOL.  II.,  SaBNCS.  2  C 


186  Proceedings  of  the  Royal  Irish  Academy. 

some  freshly  prepared  fulminate  of  iron  a  dilute  solution  of  caustic 
potash  be  carefully  added,  the  mixture  will  continue  (as  I  have  observed) 
neutral  so  long  as  the  alkali  produces  a  further  precipitate  of  the  oxide 
of  iron ;  and  when  it  ceases  to  do  so,  if  the  mixture  be  then  filtered,  a 
light  yellow  solution  will  be  obtained,  which  holds  dissolved,  as  I 
conceive,  a  double  neutral  fulminate  of  iron  and  potassium  resulting 
from  the  displacement  of  one  half  the  iron  in  the  neutral  salt,  as  is 
shown  in  the  following  equation:  2  Fe  021^,02  +  2  KHO  =  reK, 
(Cal^jO)  '  +  "Fe  0  +  HjO,  and  this  double  fulminate  develops,  as  be- 
fore observed,  the  purple  coloration  when  treated  with  a  diluted  acid, 
and  again  becomes  colourless,  or  very  nearly  so,  on  adding  an  excess  of 
alkali,  especially  after  the  application  of  heat,  and  the  colour  can  be 
again  restored  by  acidifying  the  mixture,  and  these  changes  may  be 
produced  many  times  in  succession. 

For  the  production  of  the  acid  fulminate  of  iron  the  double  neutral 
salt  is  much  preferable  to  that  of  the  simple  neutral  fulminate  of  that 
metal,  as  in  the  latter  case  there  will  be  produced,  as  before  shown, 
a  protosalt  of  iron,  which  reacts  on  the  acid  fulminate,  occasioning  its 
more  or  less  rapid  decomposition. 

I  may  further  observe,  that  on  heating  the  double  fulminate  just 
described,  there  will  be  developed  the  red  or  purple  coloration,  'onless 
there  is  present  too  great  an  excess  of  alkali ;  this  remark,  however, 
does  not  apply  to  the  case  of  ammonia,  the  excess  of  which  being  ex- 
pelled by  heat  does  not  interfere  with  its  production. 

This  development  of  the  acid  fulminate  by  heat  is  not  so  easily 
accounted  for  as  where  it  has  been  due  to  the  action  of  acids  ;  it  may, 
however,  depend  on  the  circumstance  that  the  simple  neutral,  and 
double  fulminate  of  iron,  are  both  easily  resolvable  by  heat  under  cer- 
tain conditions  into  the  acid  fulminate. 

I  shall  now  point  out  how  the  explanation  I  have  given  of  the  produc- 
tion of  the  purple  coloration  in  the  case  of  the  fulminate  of  iron  may 
likewise  serve  to  account  for  the  similar  development  of  colour,  which 
I  have  myself  observed,  in  the  reaction  of  the  f  errocyanide  of  potassium 
on  fulminate  of  mercury.  My  experiments  would  seem  to  show,  that 
when  those  compounds  react  on  each  other,  there  is  at  first  formed, 
amongst  other  products,  the  double  fulminate  of  iron  and  potassium, 
which,  like  that  salt  prepared  directly,  as  already  described,  from 
the  fulminate  of  iron,  passes  into  the  purple  acid  fulminate  of  that 
metal,  on  being  heated  or  treated  with  diluted  acids ;  the  following 
formulaB  and  equation  explaining  the  production  of  the -double  salt, 
accompanied,  as  it  is  in  this  case,  by  the  cyanide  of  mercury  and  potas- 
sium :  2  Hg  C^N.O,  +  K4  Fe  Cy,  =  Fe  K,  (C^N^O,)'  +  2  Hg  Cy,  +  2 
KCy. 

Amongst  other  facts  which  might  be  mentioned  in  support  of  the 
foregoing  statement,  is  the  following  one,  that  I  have  observed,  that 
when  the  ferrocyanido  of  potassium  and  the  fulminate  of  mercury, 
along  with  water,  react  on  each  other  at  the  ordinary  temperature,  the 
mixture  after  a  short  time  acquires  a  yellowish  tint,  which  gradually 


Davy — On  Prcperties  possessed  by  Salts  o/Fulminic  Acid,  187 

passes  into  that  of  a  reddish  shade,  and  if  a  portion  of  the  mixture  in 
this  early  stage  of  reaction  be  treated  with  a  drop  or  two  of  any  dilute 
acid,  or  is  heated,  the  deep  purple  coloration  which  results  when  the 
double  fulminate  is  similarly  acted  on  will  at  once  be  developed.  I 
shall  now  briefly  notice  some  of  the  more  characteristic  properties  of 
the  acid  fulminate  of  iron  as  obtained  by  the  action  of  the  f errocyanide 
of  potassium  on  the  fulminate  of  mercury,  most  of  my  experiments 
having  been  made  on  that  salt  as  so  procured.  When  that  compound 
is  dissolved  in  water,  it  appears  to  possess,  at  the  ordinary  temperature, 
considerable  stability,  for  it  has  been  exposed  to  the  air  and  even  light 
in  an  open  vessel  for  several  weeks,  without  its  appearing  to  undergo 
any  change  of  colour ;  but  when  the  solution  is  allowed  even  sponta- 
neously to  evaporate  to  dryness,  the  dark  purple  residue  very  soon 
passes  to  a  brown  colour,  from  the  decomposition  of  this  salt,  and  the 
separation  of  its  iron  in  the  form  of  peroxide ;  and  this  proneness  to 
decompose  in  the  dry  condition  may  account  for  the  residue  not  ex- 
ploding on  the  application  of  a  strong  heat,  the  salt  having  quietly 
decomposed  before  reaching  the  temperature  necessary  to  explode  it, 
or  other  fulminates ;  and  I  may  further  observe,  that  even  in  aqueous 
solution  it  soon  decomposes  if  the  temperature  is  raised  to  the  boiling 
point,  its  decomposition  being  attended  with  the  separation  of  per- 
oxide of  iron  ana  ammonia. 

It  does  not  appear  to  be  soluble  in  ether,^chloroform,  bisulphide  of 
carbon,  or  in  benzole,  though  it  is  readily  dissolved  by  alcohol. 

It  is  quickly  decomposed  by  strong  acids,  with  tie  evolution  of 
hydrocyanic  acid  and  the  development  of  Prussian  blue,  and  even  in 
their  diluted  condition  the  same  occurs,  but  more  slowly. 

The  caustic  alkalies,  at  the  ordinary  temperature,  slowly  discolo- 
rize  its  solution ;  with  the  assistance,  however,  of  heat  that  effect  is 
quickly  produced. 

It  appears  to  possess  but  little,  if  any  disposition  to  assume  a  crys- 
talline form,  for  as  yet  all  my  attempts  to  obtain  it  separately  in  such 
a  condition  have  been  unsuccessful. 

Several  experiments  were  made  as  to  the  effects  of  different  metal- 
lic salts  on  this  compound,  but  no  very  characteristic  results  were  ob- 
servable, except  in  the  case  of  the  nitrate  of  silver,  which  produced  a 
dull  bluish  precipitate,  leaving  the  liquid  colourless,  if  sufficient  of  the 
silver  salt  be  added.  This  precipitate,  however,  is  one  of  great  insta- 
bility, for  it  very  soon  loses  its  blue  colour  (even  when  lying  at  the 
bottom  of  the  stratum  of  liquid  from  which  it  has  been  precipitated), 
and  becomes  of  a  white  or  yellowish- white^  appearance. 

If,  however,  while  it  still  retains  its  blue  colour,  it  is  treated  with 
diluted  hydrochloric  acid,  or  with  an  alkaline  chloride,  the  solution 
regains  its  original  purple  colour,  whilst  the  chloride  of  silver  precipi- 
tates; but  if  the  addition  of  the  acid  or  chloride  be  delayed  tUl  after 
the  precipitate  has  become  white,  then  both  fail  to  reproduce  the 
purple  coloration,  owing  to  the  previous  decomposition  of  the  silver 
compound. 


188  Proceedings  of  the  Royal  Irish  Academy. 

This  red  or  puzple  combixiation  appearing  to  be  but  little  affected 
by  many  of  the  metallic  salts,  seems  to  strengthen  the  view  I  have 
taken  as  to  its  nature,  for  had  it  been  a  peculiar  cyanogen  compound, 
such  as  we  have  in  the  case  of  the  ferro-,  ferri-,  and  nitroferri-cyano- 
gen,  as  well  as  in  other  compound  salt  radicals  of  that  substance,  we 
should  have  expected  that  it  would  have  produced  very  characteristic 
effects  with  different  metallic  salts. 

I  may  further  observe  that  the  same  compound  is  formed  when  the 
ferricyanide  of  potassium  (or  as  it  is  better  known  under  the  name  of 
red  prussiate  of  potash),  instead  of  the  ferrocyanide  of  potassium  (the 
yellow  prussiate),  in  aqueous  solution  is  heated  along  with  the  fulmi- 
nate of  mercury,  and  that  it,  as  well  as  the  ferrocyanide,  even  without 
the  application  of  heat,  give  rise  to,  but  more  slowly,  the  formation  of 
the  lid  or  purple  combination,  the  ferricyanide  acting,  however,  in 
this  respect  more  readily  than  the  ferrocyanide. 

Lastly,  I  may  add  that  I  found  that  a  similar  purple  compound 
was  produced  when  the  fulminate  of  silver  was  substituted  for  the 
mercurial  salt  in  the  reactions  referred  to,  and  it  is  probable  that  some, 
at  least,  of  the  other  fulminates  would  give  rise  to  like  effects. 

I  regret  that  the  results  which  I  have  brought  before  the  Academy 
are  not,  in  some  respects,  of  a  more  definite  character ;  but  all  who 
have  experimented  on  the  fulminates  have  experienced  the  great  diffi- 
culties of  such  inquiries,  arising  from  their  instability  and  complexity 
of  constitution ;  but  I  hope  before  long  to  be  able  to  investigate  more 
fully  the  subjects  of  this  communication,  as  well  as  other  matters  bearing 
on  them.  I  trust,  however,  tha^  the  results  of  the  observations  which 
I  have  already  made  may  not  be  considered  as  devoid  of  interest,  a« 
any  facts  which  may  extend  our  knowledge  of  f ulminic  acid,  a  com- 
pound regarding  the  true  nature  of  which  chemists  are  not  yet  agreed, 
must  possess  more  or  less  interest  in  a  scientific  point. of  view ;  and  it 
is  well  known  that  many  facts  and  observations  which  at  first  have 
been  regarded  as  mere  matters  of  interest  to  men  of  science  have  after- 
wards proved  of  much  practical  utility. 


Studdeet  AND  Pldnkett — On  Watei'8  of  Idschonrnma.  189 


IX  V  111. — Ow  TfHE  CoKSTITUlirrS  OP  THB  TWO  PHIKCIPAl  MINERAL  WaTEM 
OF  LiSDOONVAfiNA,  COUNTT  OF  ClABE.     By  LANCELOT  StUDDEET,  LL.  D., 

Ex-Sch.,  T.  C.  D.,  and  William  PLtrwEEir,  F.  C*  S. 

[Read  May  24, 1875.] 

Befobs  proceeding  to  liBdbonyama  the  Authars  procured,  in  July  last, 
a  jar  of  the  principal  sulphur  water  of  the  place,  which  'was  carefully 
collected  from  the  Gowlaun  Well,  through  the  kind  aid  of  Dr.  Cullinan, 
of  Ennis ;  of  this  a  preliminary  examination  was  then  made  at  the  la- 
boratory of  the  Eoyal  College  of  Science,  Stephien's-green,  Dublin. 

In  August  they  visited  lisdoonyama,  in  order  to  determine  at  the 
springs  the  sulphuretted  hydrogen  that  might  have  escaped,  and  the 
iron  that  might  have  become  peroxidised  before  reaching  Dublin ;  and 
also  for  liie  purpose  of  procuring  a  large  supply  of  the  waters,  to  de- 
termine their  more  stable  constituents.  This  lengthened  investigation 
the  authors  were  kindly  permitted  by  Professor  Galloway  to  conduct 
in  that  laboratory^  with  all  appliances  available. 

Remaining  at  Lisdoonvama  until  the  5th  of  September,  they  re- 
peatedly estimated  at  the  well  itself  the  sulphuretted  hydrogen  in  the 
Gowlaxm  Spring,  and  in  a  secondary  one,  near  the  east  end  of  the 
parish  church.  They  also  determined  th^  iron  present  as  protoxide  in 
a  principal,  and  also  in  a  secondary,  chalybeate  well,  both  situated  in 
an  enclosure  at  Bathbawn  Bridge,  nearer  to  the  town  of  Lisdoon* 
vama. 

It  may  be  right,  perhaps,  to  remark  that  there  are  no  interments 
in  the  churchyard ;  that  spring  there  issues  from  the  clifp-side,  and  is 
one  of  a  pair  of  spas,  sulphur  and  iron,  in  one  recess,  and  nearly  join- 
ing at  their  mouths,  thence  called  the  *'  Twin  Spas."  The  iron  one 
was  not  flowing  in  September  last ;  and  neither  of  these  iieems  to  have 
been  sent  for  analysis  to  Professor  Apjohn  in  1856.  There  wias  indeed 
another  chalybeate  water  sent  then  to  the  laboratory  of  that  eminent 
chemist  from  the  ''  Spectacle  Biidge  "  Spa,  still  farther  frotn  Lisdoon- 
vama town ;  but  the  well  is  now  closed  by  cattle  tracks,  and  is  re- 
ported by  a  writer  (Dr.  Faussett)  to  have  beai  disused  in  1867. 

The  temperature  (which  is  said  to  be  equable)  of  the  two  sulphur 
and  two  iron  spas  so  examined  by  the  authors  was  ascertained  as  com- 
pared with  that  of  the  atmosphere ;  also  the  rate  of  flow  of  the  ''  Twin 
Sulphur  Spring ;"  but  the  underground  position  of  the  springs  at  Gow- 
laun and  Bathbawn  prevented  their  rate  of  flow  being  determined. 
However,  notwithstanding  their  many  drinkers,  the  level  of  these  two 
principal  wells  is  said  to  be  rather  constant. 

It  should  be  noted  that  during  this  visit,  and  for  some  days  before, 
the  weather  was  wet.  The  rain  seemed  to  dilute  the  spas ;  for  even  the 
drinkers  remarked  them  weaker  in  taste.  The  explanations  to  accom- 
pany Sheets  114,  122,  and  123  of  the  maps  of  the  Geological  Survey 


190  Proceedings  of  the  Royal  Irish  Acadeiny, 

of  Ireland,  illustratmg  parts  of  the  Counties  of  Clare  and  Oalway,  by 
Mr.  Frederick  J.  Poot,  M.  A.,  giye  the  geological  formation  of  the 
Lisdoonyama  district,  which  may  account  for  the  nature  of  its  springs. 
At  page  27,  Mr.  Foot  observes  that ''  Iron  occurs  in  the  form  of  iron- 
stone nodules  and  thin  bands  in  the  shales  about  Lisdoonvama,  .  .  . 
also  as  iron  pyrites,  with  the  crystals  of  which  mineral  (he  adds)  the 
black  fissile  iSiales,  when  they  are  unweathered,  may  be  seen  coated." 
He  seems  correct  in  remarking  (page  28)  that  ''  It  is  from  the  decom- 
position of  the  iron  pyrites  [sulphide  of  iron]  in  the  coal  measures 
that  these  wells  [at  LiBdoonTamaJ  derive  their  sulphur  and  iron." 

It  may  be  added,  in  passing,  that  Mr.  Foot  gives  a  correct  wood- 
cut of  the  "  Twin  Spas"  as  Figure  9  of  his  report. 

Following  the  suggestion  of  a  recent  eminent  writer,  from  a  medical 
point  of  view,  on  these  and  other  spas  of  Ireland  (Dr.  Mapother),  who 
advised  lithia  to  be  looked  for  in  the  Gowlaun  water,  the  authors 
made  that  search  by  means  of  the  spectroscope,  and  the  presence  of 
lithia  (by  its  distinctive  band)  was  ascertained,  but  in  amount  too  mi- 
nute for  a  quantitative  determination  in  the  supply  of  water  available. 
This  constituent  seems  to  have  been  detected  in  this  water  now  for  the 
first  time.  Dr.  Mapother  relies  on  it  as  a  curative  agent  of  much 
value. 

Another  medical  gentleman,  Mr.  William  Faussett,  M.  B.,  F.  B.  C.  S., 
who  visited  Lisdoonvama  in  1867,  as  he  says,  ''  for  his  own  health's 
sake,"  states,  in  an  account  of  his  visit  (page  13),  that  ''  The  sulphur 
and  chalybeate  springs  of  Lisdoonvama,  when  judiciously  used,  and 
supplemented  as  occasion,  in  some  cases,  may  require,  possess  an  ex- 
tensive range  of  therapeutical  action  ;  and  being  free  horn,  the  excess 
of  any  irritating  ingredients,  such  as  common  salt,  will,  on  this  ac- 
count, be  found  more  beneficial  than  spas  which  have  hitherto  been 
held  in  higher  repute." 

Since  &en  (it  seems  it  was,  that)  the  present  excellent  pump-room 
was  built  over  the  Gowlaun  Well.  In  September  last  the  local  phy- 
sician. Dr.  Stackpoole  Westropp,  was  erecting  some  baths  near  it, 
much  desired  by  patients  and  their  professional  advisers.  Dr.  Apjohn 
remarked,  in  1856,  that  the  Oowlaun  water  was  ''used  externally  as  a 
bath." 

Of  the  several  springs  at  Lisdoonvama  two  are  chiefly  resorted  to, 
namely,  the  before-mentioned  sulphur  spring  known  as  Gowlaun,  and 
the  principal  chalybeate  spring  at  Rathbawn.  The  following  are  the 
results  of  the  examination  made  of  them : — 

GOWLAUN. 

'  The  temperature  of  this  water,  as  drawn  from  the  well,  was  found 
to  be  11°  C,  the  air  at  the  time  being  15.5°  C.  It  contains,  in  addi- 
tion to  the  usual  constituents  of  well  water,  5.553  cubic  centimeters 
of  sulphuretted  hydrogen  in  the  litre.  The  unoxidized  sulphur  exists 
entirely  combined  with  hydrogen.   It  also  contains,  as  before  mentioned, 


Studdert  AND  Plunketi>— On  Waters  of  Lisdoonmnna.  191 

traces  of  lithia.    The  following  table  gives  the  quantities  of  the  several 
constituents : — 


Silica  

Sulphuric  acid,  calculated  as  SOa 

Chlorine  

Liine  precipitated  on  boiling,  calculated  as  Ca 
Lime  retained  in  solution  on  boiling,  calculated 

as  Ca  

Magnesia  precipitated  on  boiling,  calculated  as  Mg 
Blagnesia  retained  in  solution  on  boiling,  calculated 

as  Mg 
Lithia 

Soda,  calcTdated  as  Na 

Potash,         „         K  


Parts  in 

Grains  in 

one  million. 

one  gallon. 

13.6 

.952 

10.0 

.700 

29.6 

2.072 

35.0 

2.460 

2.7 

.189 

17.1 

1.197 

.098 

1.4 

Traces. 

Traces. 

61.9 

4.333 

3.0 

.210 

Which  may  be  calculated  as  being  in  combination  thiifl : — 


Silica             ..             

13.6 

.952 

Calcic  carbonate            

87.5 

6.126 

Magnesic    „                  

60.1 

4.207 

Sodic           „                 

102.3 

7.161 

Calcic  sulphate              

8.1 

.667 

Magnesic  „                   

6.0 

.420 

Sodic  chloride               

44.4 

3.108 

Potassic    „                   

5-7 

.399 

327.7 

22.939 

c.  c.  per  litre. 

Sulphuretted  hydrogen            

5.553 

The  specific  gravity  referred  to  water  at  15°  C.  was  1.0006. 


Bathbawk  Chalybeate. 

The  temperature  of  this  water  was  found  to  be  13°  C,  when  that 
of  the  air  was  15°.l  C,  being  a  difiFerence  of  only  2°.l,  whilst  in  the 
case  of  the  Gowlaun  water,  the  dijfference  was  4°. 5  :  this  may  be  ac- 
counted for  by  the  more  open  situation  of  this  well,  which  is  more 
freely  exposed  to  sunshine.  This  water  contains,  in  addition  to  the 
usuidly  occurring  substances,  a  ferrous  salt,  and  also  a  weighablo 
quantity  of  manganese ;  this  latter  substance  does  not  appear  to  have 
been  before  detected.     The  several  constituents  are  : — 


192 


ProceecUngt  of  the  Boyai  Iriah  Academy. 


Parts  in 

Grains  in 

one  million. 

one  ptUon. 

Silica                 

12.1 

.847 

Sulphuric  acid,  calculated  as  SO4       

124.7 

8.729 

Chlorine             

35.6 

2.486 

Iron,  calculated  as  Fe              

17.1 

1.197 

Manganese      „     Mn              

0.8 

.066 

Lime  precipitated  on  boiling,  calculated  as  Ca 

56.0 

3.920 

lime  retained  in  solution  on  boiling,  calculated 

asCa          

24.8 

1.736 

Magnesia  precipitated  on  boiling,  calculated  as  Mg 

2.7 

.189 

Magnesia  retained  in  solution  on  boiling,  calculated 

wMg         

16.8 

1.176 

Soda  calculated  as  Na 

20.6 

1.436 

Potash  calculated  as  K            

2.6 

.176 

Whicli  may  be  calculated  as  being  in  combination  thus  : — 


Silica                  

12.1 

.847     * 

Ferric  oxide,  with  trace  of  alumina 

2.7 

.189 

Ferrous  carbonate         

31.7 

2.219 

&°°'"  ;;      ::    ::    :;    : 

1.7 

.119 

140.0 

9.800 

Magnesic        „              

9.6 

.666 

Calcic  sulphate              

84.3 

6.901 

Ma^esic    „                  

84.0 

6.880 

Sodic  chloride               

62.1 

3.647 

Potassic    „  ..              

6.4 

.448 

424.6 

29.716 

The  specific  gravity  referred  to  water  at  15°  C.  was  1 


,0006. 


In  the  same  enclosure  with  the  last  mentioned,  is  another  chaly- 
beate, know  as  the  Magnesian  iron  water.  As  it  has  now  fallen  into 
disuse,  it  did  not  seem  necessary  to  do  more  than  determine  the  iron 
which  it  contains.  Calculated  as  carbonate,  it  was  14.9  Mgr  per  litre, 
or  1.043  grains  per  gallon. 

Of  that  remarkable  pair  the  '*  Twins,"  only  one — the  sulphur 
water — ^was  flowing ;  it  is  essentially  of  the  same  character  as  the 
Gowlaun  water.  It  contains  2.052  cub.  cent,  sulphuretted  hydrogen 
per  litre.  The  temperature  was  11°.6  C,  the  air  being  15°.4  C.  The 
rate  of  flow  was  found  to  be  one  litre  discharged  in  one  minute  and 
twenty  seconds,  or  about  ten  gallons  in  one  hour. 


Baker — On  the  Ligamentum  Mucosum.  193 


XXIX. — Ok  the  LiGAMEinuM  Mucosuir.  By  Aethtte  "Wrsroowii 
"WiLLEHX  Bakeb,  B.  a.,  Student  in  Medicine,  Trinity  College, 
Dublin. 

[Read  April  27, 1876.] 

The  ligamentum  mucosum  of  the  knee  joint  being  so  very  slightly 
noticed  by  anatomists  in  general,  and  the  information  respecting  it  so 
scanty,  it  has  been  suggested  to  me  that  I  should  keep  notes  of  some 
of  those  I  found  during  the  past  winter  session,  and  these  notes  I  now 
bring  under  your  notice. 

Before  giving  the  result  of  my  own  observations,  it  may  be 
necessary  to  review  the  literature  of  the  subject.  The  first  notice  of 
it,  of  which  I  am  aware,  is  by  Vesalius  (Op.  Venetiis,  1568,  p.  270), 
who  records  its  existence  in  these  words : — '*  Verum  praeter  hoc  liga- 
mentum interdum  adhuc  mucosum  quoddam  et  gracile  reperias,  in  medio 
genu  articuli  locatum.''  The  anatomists  who  followed  him  added 
nothing  to  his  description  until  the  publication  of  "Walther's  Obser- 
vationesde  articulis  et  ligamentis  incessu,  statuque,  &c.  (Lipsise,  1728, 
p.  8),  who  refers  to  its  relation  to  the  mass  of  fat.  But  the  fullest  of 
the  old  descriptions  is  that  of  Weitbrecht,  who,  in  his  Syndesmologia 
(Pctropol.,  1742),  says,  ''Ex  cjusdem  zonae  pinguedinossD  sedd 
inferiore  cducitur  appendix  aliqua  ejusdcm  substantisB  sod  plurimis 
fibris  intexta,  ope  quarum  in  latere  dextro  sulci,  qui  est  onterius  juxta 
capitulum  externum  femoris  supra  ligamentum  cruciatum  anterius 
cui  accumbit  infigitur.  Hsb  fibne  an  duplicaturanim  continuationcs 
sint,  an  vero  ex  ipsa  patella  proveniant  ut  "Winslow  vult  difficulter 
extricari  potest,  magis  tamen  assentiendum  Walthcro  mihi  videtur 
qui  id  de  pinguedine  tcrminari  perhibet."  Referring  to  Winslow's 
description  shows  us  that  it  is  an  incorrect  one,  as  even  in  the  fifth 
edition  of  his  ''Anatomical  Exposition  of  the  Structure  of  the  Human 
Body"  (1775),  ho  says  (p.  130),  "it  is  attached  to  the  lower  part 
of  the  cartilaginous  side  of  the  patella  by  one  end,  by  the  other 
to  tho  anterior  part  of  the  great  notch  between  the  femoral  con- 
dyles." He  says  its  use  is  to  hinder  the  fat  from  being  compressed 
in  motion  of  the  knee.  Other  old  anatomists,  Kerckring,  Blancard, 
&c.,  add  nothing.  Among  the  modem  anatomists  the  ligament  is 
passed  by  with  as  trifling  notice.  Boycr  names  it  the  adipose  liga- 
ment. Cruveilhier  (Anatomic,  1834,  p.  469),  says  that  sometimes  it 
iis  absent,  sometimes  multiple ;  ho  has  seen  a  fold  of  this  nature 
stretching  from  the  membrane  over  the  extensor  tendon  to  the  supra- 
trochlear part  of  the  femur.  Mr.  B.  Cooper  in  his  Lectures  (1829,  p. 
275)  says  it  is  composed  of  a  number  of  little  fimbriated  processes 
which  receive  the  branches  of  the  articular  artery.  Barkow  calls  it 
**  ligamentum  suspcnsorium  marsupii,"  as  he  has  named  the  alar 
ligaments  tho  "marsupium  patellare."     Henle*  says  of  it,   ''The 


*  Bimderlehe,  2nd  edition,  p.  153. 

fi.  X.  A.  PBOC,  SBB.  U.,  VOL.  II.,  8CIEirCB« 


2D 


194  Proceedings  of  the  Boyal  Irish  Academy. 

origin,  strength,  and  connexions  of  tliis  ligament  are  variable.  I  saw 
it  of  the  thickness  of  a  coarse  thread  only,  made  up  of  an  arterial  and 
venous  stem,  and  a  pair  of  bundles  of  connective  tissue ;  usually  it  is 
flat  and  broad  towards  its  insertion,  cylindrical  medially,  and  knotty 
by  its  including  several  fatty  lobes."  Luschka  says,*  "That  only 
exceptionally  does  it  form  in  man  a  membranous  sagittal  septum,  which 
completes  the  partition  of  the  synovial  cavity  of  the  knee  into  two 
lateral  halves,  a  partition  partly  begun  by  the  crucial  ligaments." 
Bobertsf  adds  little  more  in  his  monograph.  Hyrtl  remarks,  **  In 
spite  of  its  slendemess  and  often  thread-like  proportions,  this  band  is 
called  the  mucous  ligament ;  it  is  often  absent  or  appears  knotty  from 
including  fat,  or  it  includes  a  fibrous  string  which  conveys  blood  ves- 
sels to  the  patella,  these  seem  to  All  vacant  spaces  in  the  joint." 
Cloquet  describes  it  as  an  adipose  canal. 

Before  bringing  forward  the  details  of  my  own  observations,  I  wish 
to  explain  the  following  division  which  I  have  adopted. 

Glass  I.  Contains  those  cases  where  the  ligament  formed  a  com* 
plete  septum  across  the  joint. 

Class    II.  Where  it  formed  a  partial  septum. 

Class  III.  Where  it  existed  as  a  coarse  thread  or  threads. 

Class  IV.  Where  the  ligament  was  absent. 

To  this  I  have  added  notes  on  the  comparative  anatomy  of  the 
ligament. 

The  total  number  of  cases  occurring  in  each-  class,  together  with 
the  average  strain  it  took  to  break  them,  is  as  under : — 

Class  I.  There  were  9  cases  (22^  per  cent.),  average  strain, 
21.24  lbs. 

Class  II.  There  were  9  cases  (22^  per  cent.),  average  strain, 
15.00  lbs. 

Class  III.  There  were  19  cases  (47^  per  cent.),  average  strain 
9.19  lbs. 

Class  rV.  There  were  3  cases  (7^  per  cent.) 

Class   V.  There  were  20  cases. 

In  Class  I.  the  measurements  were  taken  in  this  manner : — 

Anteriorly.  From  the  marsupium  to  the  femoral  notch. 

Posteriorly.  From  the  anterior  crucial  ligament  to  the  femoral 
notch. 

Above.  The  femoral  attachment. 

Below.  From  the  marsupium  to  the  anterior  crucial  ligament. 


*  Nur  ausnahmweiAe  bildet  das  ligamGtitum  mucosiim  beim  Menschen  ein 
membranoses  sagittal  gestelltes  Septum  welches  die  schon  durch  die  ligameDtum 
cruciatum  eingeleitete  sondenmg  des  gelenkes  iH  zwei  seitenhalften  yervollstandigt, 
Anat.  des  Menschen,  1865,  Bd.  3,  pt  1,  p.  376.  [I  am  indebted  to  Dr.  Macalister 
for  the  translationfi]. 

t  Untersuchmigen  iiber  die  anatomie  iind  mechatiik  des  kniegelenkes,  Giessen, 
1855. 


Bakeb — On  the  Ligamentum  Mueoaum, 


m 


CLAH3  I,— Cea^LETS  SSPTA, 


IB 


Ma 


1.  The  fii5t  complete  septum  t  saw,  I 
regret  I  iroa  imalilc  to  meiuure,  oa  it  was 
a  very  fine  specimen. 

2.  The  ligament  was  attached  to  the 
external  side  of  the  femoral  notch,  and  con- 
tained a  vessel. 

3.  The  fellow  ligament  of  No.  2  carried 
sereral  vessels,  and  was  attached  to  the 
external  part  of  the  notch ;  I  also  phserved  a 
second  mucous  ligament  going  from  the  mar- 
supium  to  the  snyovial  hood  which  is  often 
found  on  the  internal  condyle.  Though  a 
mere  thread,  this  ligament  was  of  consider- 
able strength,  having  a  triangular  origin  and 
insertion;  it  measured  1.26  inches  in  length, 
and  is  the  second  of  the  Idnd  I  have  observed 
in  man. 

4.  There  was  no  communication  between 
the  subcmreal  bursa  and  the  synovial  cavity 
of  the  joint;  the  inner  condyle  had  a  free 
fimbria  attached  to  it. 

5.  Was  composed  of  separate  threads  at 
the  anterior  portion ;  was  fellow  of  No.  4. 

6.  Was  broader  at  the  anterior  portion,  and 
T-shaped,  like  the  ligamentum  mucosum  in 
the  Otter. 

7.  Was  slightly  notched  at  its  femoral 
attachment,  and  had  no  trace  of  any  vessel ; 
but  there  was  a  slip  going  from  the  middle 
of  the  ligament  to  the  external  side  of  the 
femoral  notch. 

8.  No  trace  of  any  vessel ;  in  testing  the 
strain  it  broke  cleanly  from  its  femoral  origin. 

9.  Was  so  much  inflamed  that  I  did  not 
think  it  worth  while  testing  the  strain. 


M. 


1.25 
1-00 


110 
0*96 


0-76 
0-55 


F. 


F. 


M 


0-76 

100 
0-75 

0-75 

0-60 
0-80 


0.90 

0-80 
0*85 

0-85 

0-85 
0-70 


0-70 

0-50 
0-70 

0-85 

0-65 
0-86 


0-90 
100 


21 


0-90 

0-90 
0-70 

0-90 

0-80 
0-40 


24-6 

14 
19 

14 
28-6 


196  Proceedings  of  the  Royal  Irish  Academy. 

Fig.  1,  Eefera  to  No.  16,  Claas  III. 


Fig.  2.  Eefers  to  No.  3,  Claas  11. 


p  =  Patella. 

a  =  Mass  of  fat. 

b  =  Bursa. 

t  =  Tibia. 

/  =  Femur. 

X  =  Anterior  crucial 

ligament. 
m  =  Ligt.  mucosum. 


p  =  Patella. 
a  =  Mass  of  fat 
b  =  Bursa. 
t  ^  Tibia. 


*^^' V^^i    J      /  =  Femur. 


X  =  Anterior  crucial 

ligament. 
tn  =  Ligt.  mucosum. 


Basbb — On  the  Ligamentum  Mueosum. 


197 


Class  II.— Partial  Septa. 


i 


^ 


i« 


1.  Had  a  falciform  edge  at  femoral  attach- 
ment. 

2.  Had  a  falciform  margin  looking  downwards 
and  backwards. 

3.  The  ligament  was  inflamed,  the  subject 
itself  was  old,  thin,  and  had  numerous  bed-sores 
upon  her.    Fig.  2.  ' 

4.  Had  a  falciform  margin.  I  had  not  weights 
to  measure  what  strain  it  would  bear. 

6.  Had  a  falciform  edge,  and  broke  from  its 
femoral  attachment,  where  there  was  some  trace 
of  a  yessel. 

6.  A  rickety  subject,  in  whom  the  testes  had 
not  descended ;  the  ligament  carried  many  vessels. 
I  observed  a  fine  uiread  extending  from  the 
middle  of  the  ligament  to  the  anterior  crucial 
ligament  at  its  latter  extremity ;  it  expanded  into 
a  reddish  cone-like  thickening ;  this  thread  mea- 
sured 0-6  inch  in  length. 

7.  The  fellow  limb  of  No.  6  had  a  slight  falci- 
form edge,  and  broke  from  the  marsupium ;  not- 
withstanding its  being  a  smaller  lig^ament  than 
the  preceding,  it  bore  a  greater  strain,  in  conse- 
quence of  a  large  vessel  running  along  the 
posterior  margin,  which  came  from  the  azygos 
articular  artery. 

8.  Had  a  falciform  margin,  a  second  slip  went 
from  its  femoral  attachment  to  the  anterior  crucial 
ligament,  and  a  third  slip  joined  the  marsupium 
to  the  outer  reflection  of  the  synovial  membrane; 
the  vessels  on  its  surface  were  from  the  internal 
and  external  superior  articular  arteries ;  there  was 
a  hood  on  the  inner  condyle. 

9.  Had  a  falciform  femoral  attachment ;  two 
threads  went  from  this  ligament  to  the  anterior 
crucial  ligament,  and  a  third  thread  joined  the 
marsupium  to  the  external  reflection  of  the 
s3rnovial  membrane;  there  was  a  hood  on  the 
inner  condyle.    Fig.  3. 


M. 


F. 


M. 


B. 


L, 


B. 


Inches 
0*80 

0*80 

0-66 

0-70 
0-60 

100 


0-80 


0-80 


1-20 


Inches, 
0-30 

0-30 

0*90 

0-20 
0-26 

0-40 


016 


0-35 


0-30 


Lbs. 
21-6 
16'0 
29*5 


10-5 
140 

16-6 

70 

6-0 


198 


Proceedings  of  the  Boyal  Irith  Academy. 


Class  III.— Coarse  Thread  or  Threads. 

1 

i 

! 

4 

Inches. 

Indies. 

Lbt. 

1.  A  coarse  thi«ad. 

M. 



0-90 

0-20 

1-0 

2.  Was  double  at  its  origin  and  insertion ;  had 

F. 

— 

0-66 

— 

2-5 

a  trace  of  a  vessel  at  its  insertion. 

3.  Carried  a  vessel  from  the  superior  external 

F. 

— 

0-95 

0*30 

7-0 

articular  artery. 

4.  Had  a  second  thread  underneath,  and   a 

F. 

E. 

0-80 

0-10 

26*0 

vessel  from  the  superior  internal  articular  artery. 

5.  There  was  a  thin  synovial  reflection  like  a 

F. 

L. 

0-70 

0-10 

22*0 

nidimentary  septum,  behind  or  posterior  to  the 

ligament.    This  was  fellow  limb  of  preceding. 
6.  Was  so  thin  I  did  not  test  its  breaking 

M. 

L. 

0-95 

_ 

_ 

strain. 

7.  Had  no  trace  of  any  vessel,  and  was  com- 

F. 

R. 

0-55 

— 

6*0 

posed  of  two  threads,  one  of  which  was  inserted 

0.2  inch  below  the  femoral  notch;  the  other  was 

attached  to  the  outer  condyle. 

8.  Broke  at  femoral  attachment  in  testing  the 

M. 

E. 

0-45 

— 

60 

strain. 

9.  Broke  at  femoral  attachment. 

M. 

L. 

0-60 



100 

10.  Slight  trace  of  a  vessel  near  the  marsupium. 

F. 

R. 

0-96 

— 

3-60 

11.  Thero  was  a  well-formed  hood   on   the 

M. 

L. 

MO 

— 

IV6 

internal  condyle;  the  ligament  broke  from  its 
femoral  attachment,  and  a  slip  went  from  about 

the  middle  of  this  ligament  to  the  anterior  crucial 

ligament ;  a  second  slip  went  from  the  femoral 

attachment  to  a  fatty  mass  on  the  anterior  crucial 
ligament. 

12.  This  ligament  existed  in  a  subject  with 

F. 

R. 

0-50 

0-15 

14-0 

very  long  lower  limbs. 

13.  The  weight  was  not  very  accurate  in  this 

F. 

L. 

100 

0-20 

60 

case. 
14.  Carried  several  vessels,  though  only  the 

F. 

R. 

0'66 



70 

diameter  of  a  coarse  thread,  and  broke  from  its 

femoral  attachment. 

15.  Was  a  double  throad,  and  had  no  trace  of 

M. 

R. 

0-65 

— 



vessels. 

16.  Had  a  second  band,  of  the  same  size  and 

F. 

L. 

0-60 

— 

^ 

thickness  as  the  ligament  itself,  going  from  its 

femoral  attachment  to  the  anterior  crucial  liga- 

ment.  The  joint  could  only  be  JUxed  to  a  limited 
extent  until  both  the  aeeeaeory  band  and  ligament 

tcere  burst  through.    Fig.  1. 

17.  Was  a  slender  thread. 

M. 

L. 

100 

— 

18.  Contained  a  vessel,  and  a  fatty  lobe  in  the 

M. 

R. 

1-20 

— 

— 

middle. 

19.  The  fellow  limb  of  preceding ;  both  had 

M. 

L. 

1-25 

— 



traces  of  hoods  on  their  internal  condyles. 

Bakek — On  the  lAgammtum  Mucomm, 


199 


Class  IV.— Ligament  was  absent. 


1.  It  probably  existed  at  some  time  during  life.  There  were  slight 
traces  of  a  hood  on  the  internal  condyle.  The  fellow  limb  of  No.  8, 
Class  III. 

2.  Some  remains  at  the  marsupium  as  if  it  had  existed. 

3.  Some  remains  at  the  marsupium ;  also  traces  of  rheumatic  disease. 


M. 


L. 


Fig.  3.  Eefers  to  No.  9,  Class  II. 


\    p  =  Patella. 
a  —  Mass  of  fat. 
b  ^  Bursa. 
t  =  Tibia. 
/  =  Femiur. 
X  B  Anterior  crucial 

ligament. 
i»  =  Ligt  mucosum. 


Notes  on  the  Compaeative  Anatomy  of  the  Ligament. 

Siredan  maeulatum.  The  extensor  tendon  arose  from  the  front  of 
the  femur,  and  the  ligament  existed  behind  it  as  a  lamina  of  synovial 
membrane. 

Eana  mugiem.  The  S3moyial  membrane  was  separate  from  the 
rectus  tendon,  so  that  on  cutting  the  latter  across  and  throwing  it  down 
the  joint  was  unopened.  On  opening  the  joint  the  ligament  was  seen 
beneath  the  tendon  that  traverses  the  joint,  and  was  connected  with 
the  Bemilunar  cartilage^ 


200  Proceedings  of  the  Royal  Irish  Academy. 

T(^U9  teguixin,  Tho  ligament  consisted  of  a  band  connecting  the 
internal  part  of  the  femoral  notch  with  the  anterior  portion  of  the 
internal  semilunar  cartilage. 

Iguana  rhinolophis.  Same  as  in  preceding  case  ;  was  a  strong, 
fibrous  band,  quite  separate  from  the  crucial  ligaments. 

Ameiva  lineolata.  Same  as  before ;  was  a  flat  membrane.  A  sort 
of  horizontal  septum. 

Amphiholurw  harhatus.  Same  as  before ;  tho  internal  semi-lunar 
cartilage  was  attached  to  the  internal  condyle  by  a  band  of  synovial 
membrane. 

Chameleo  mlgaris,  I  examined  two  specimens  of  this  reptile,  in 
both  of  which  the  ligament  was  absent. 

Moloch  horridus.     Same  as  in  Amphiholurus  harhatus, 

Ecphymotes  obtusirostris.  A  mere  thread,  attached  like  the  pre- 
ceding ligament ;  there  was  a  second  band  of  some  width  going  to  the 
internal  condyle. 

Croeodilus  hiporcatus.  This  was  a  very  young  specimen,  the  liga- 
ment existed  as  in  the  lizards. 

Tatfisia  hirsuta.  The  ligament  formed  a  complete  septum,  was 
T-shapcd,  and  formed  the  sheath  of  the  extensor  tendon. 

Sheep,  Formed  a  complete  septum,  and  was  roofed  in  on  the 
external  side  by  the  synovial  membrane  which  formed  the  sheath  of 
the  extensor  tendon ;  there  were  vessels  on  its  surface  from  tho  exter- 
nal articular  and  azygos  arteries. 

Lutra  vulgaris.  The  ligament  was  T-shaped,  and  formed  a  com- 
plete septum. 

Nasua  narica.  It  formed  a  complete  septum,  the  synovial  mem- 
brane being  reflected  over  the  marsupium,  thus  roofing  in  the  cavity. 

Cants  familaris  var.  Was  composed  of  several  threads  containing 
fat,  and  a  vessel  from  the  superior  internal  articular  artery. 

Ursiu  lasiotus.     Was  loaded  with. fat;  did  not  form  a  septum. 

Ursus  Himalayanus.  It  formed  a  complete  septum,  and  at  the 
posterior  border  was  traversed  by -a  large  branch  from  the  azygos 
articular  artery. 

PreshyUs  comatus.    The  ligament  was  absent. 

Cercopithecus  griseo-viridis.     It  existed  as  a  coarse  thread. 

Cereopithecus  mana.  In  the  right  limb  the  ligament  was  a  mere 
thread,  in  the  left  limb  it  was  double,  one  thread  being  attached  to 
the  external  condyle. 


In  conclusion  I  wish  to  draw  attention  to  some  points  which 
anatomists  have,  I  think,  stated  wrongly,  or  passed  over  without 
notice. 

1.  Luschka  says,  "  That  only  exceptionally  does  it  form  in  man  a 
membranous  sagittal  septum."  Kow,  it  appears  to  me  that  the  com- 
plete septum  is  somewhat  more  than  an  exception,  seeing  that  nearly 


Baker — On  the  Idgamentum  Mucosum.  201 

one-fourth  (22^  per  cent.)  of  my  cases  deserved  that  title ;  and  if  the 
number  of  partial  septa  be  taken  into  account,  I  think  the  tendency  of 
the  ligament  in  man  is  quite  as  much  towards  the  septate  condition  as 
the  filiform. 

2.  Hyrtl  remarks,  "It  appears  knotty  from  fat,  or  it  includes  a 
fibrous  string  which  conveys  blood-vessels  to  the  patella ;  these  seem  to 
fill  vacant  spaces  in  the  joint."  "With  the  first  part  of  this  statement 
I  entirely  disagree,  for,  in  those  specimens  I  examined,  the  vessels  did 
not  approach  the  patella  at  all,  but  went  rather  to  the  femoral  attach- 
ment of  the  ligament  (»'. «.,  the  intercondyloid  portion  of  the  femur) ; 
whether  they  nourished  that  portion  of  the  bone  or  not,  I  am  not  pre- 
pared to  state :  with  the  latter  part  of  his  statement  I  feel  inclined  to 
concur,  for,  as  far  as  I  can  judge,  the  function  of  the  ligamentum 
mucosum  is  to  adjust  the  fatty  lobe  at  tho  marsupium  patellare,  to 
fill  the  various  vacant  spaces  in  the  joint,  in  the  different  positions 
between  complete  flexion  and  extension. 

3.  In  several  of  the  lower  animals  I  observed  that  when  the  liga- 
ment formed  a  complete  septum,  it  was  continuous  with  the  synovial 
membrane  forming  the  sheath  of  the  extensor  communis  digitorum, 
which  passes  across  the  external  side  of  the  joint,  and  at  the  same 
time  roofs  in  the  outer  division  of  the  joint.  In  some  human  joints  I 
found  bands  going  from  the  marsupium  to  the  extemJEd  reflection  of 
the  synovial  membrane. 

4.  On  two  separate  occasions,  in  man  I  observed  an  additional  liga* 
ment  going  from  the  marsupium  to  the  hood  that  is  often  found  on  the 
internal  condyle ;  in  Scphymotes  obtusiroBtrw  this  ligament  existed 
as  a  strong  fibrous  band. 

5.  With  regard  to  the  development  of  this  ligament  nothing  is  as 
yet  known ;  it  is  a  point  which  would  probably  clear  up  its  morpholo- 
gical nature,  and  throw  light  on  the  vexed  question,  ''  the  origin 
of  synovial  membrane,"  on  which  much  has  been  written,  and  of  which 
the  best  modem  exposition  is  that  published  this  year  in  Leyden,  by 
J.  G.  Yan  dcr  Sluijs  (Over  den  Bouw  van  het  Synoviaalvlies,  Leiden, 
P.  Somerwil,  1875). 


E.  L  A.  P&OC,  SEB.  U.,  VOL.  n.,  SCIENCB*  2  £ 


202  Proceedings  of  the  Royal  Irish  Academy. 


XXX. — On  Some  Forms  of  the  Lioamentuk  Pteetgo-spikosum.  By 
A.  Macalisteb,  M.  B.,  Professor  of  Comparatiye  Anatomy,  Dublin 
University.     (With  Plates  19  and  20). 

[Read  April  27,  1876]. 

The  bony  arch  stretching  from  the  outer  pterygoid  plate  to  the  spina 
angularis  of  the  sphenoid  bone  has  been  described  by  many  authors ; 
Dieterich,*Gruber,  Barkow  as  well  as  the  manual  writers  have  noticed 
its  existence  and  some  of  its  forms.  Its  most  common  condition  in 
man  as  the  ligamentum  pterygo-spinosum  has  been  shown  by 
Civininif  and  its  comparative  anatomy  as  the  representative  of  the  canal 
or  foramen  present  in  the  ecto-pterygoid  plate  in  Rodents  has  been 
abundantly  referred  to  by  these  writers. 

The  object  of  the  present  paper  is  to  catalogue  the  very  varying 
forms  of  this  ligament  found  in  the  skulls  in  the  collection  of  the 
Dublin  University. 

The  ligamentum  pterygo-spinosum  is  an  upward  and  forward  elonga- 
tion of  the  fascial  fold  which  forms  the  internal  lateral  ligament  of  the 
mandible,  and  usually  appears  as  a  flat  band,  wider  at  its  ptery- 
goid  than  at  its  spinous  attachment,  but  variable  in  shape,  lying  usually 
internal  to  the  Arteria  meningea  media,  external  to  the  tensor 
palati,  which  often  takes  an  additional  origin  from  it ;  posteriorly 
and  internally  it  is  related  to  the  fibrous  capsule  of  the  Eustachian 
tube,  to  which  it  is  often  tightly  bound. 

Beside  the  simple  ligamentum  pterygo-spinosum,  there  exists 
very  often  a  second  band  connected  with  it  at  its  pterygoid  end 
(PI.  20,  fig.  14  a),  but  inserted  external  to  the  foramen  spinosum  into 
a  small  spur.  This  little  process  is  very  frequently  present  as  a  sharp 
tooth  on  the  outside  of  the  oval  and  spinous  holes  (figs.  1,  2  a),  and 
the  band  attached  to  it  is  much  shorter,  higher  up,  and  bounds  a 
narrower  archway;  to  this  second  ligament  the  name  ligamentum 
pterygo-spinosum  accessorium  is  applicable,  it  roofs  over  the  nervus 
temporalis  profundus  and  n.  massetericus  (fig.  14  ^  if').  This  ligament 
may  be  separate  from  the  first  named,  or  joined  to  it  at  its  pterygoid 
end,  or  for  most  of  its  extent,  and  only  separated  where  it  is  pierced 
by  the  middle  meningeal  artery  and  some  nerve  filaments. 

Of  the  bony  arrangements  coexisting  with  these  ligaments  there 
are  the  following,  and  I  have  appended  thereto  the  proportional 
frequency  of  their  occurrence  out  of  144  skulls. 

1st.  The  existence  of  the  ligament  with  no  ossified  tooth  on  the 
external  pterygoid  plate.  This  occurred  in  fifteen  of  the  skulls  on 
both  sides,  and  in  four  on  one  side  only.    In  one  of  these  the  nervus 

*  Dieterich,  Beschreibtmg  einiger  abnoifmitlltdn  des  Mensohen-fohadelfli  Basel, 
1842,  p.  9. 

t  Schmidt's  Jahrbiioher,  1853. 


Hacalister — On  Ligamentum  PteiygO'ynnosum.        303 

■pmonis  of  LnBchka  (Miiller's  Archir.,  1853),  traveiBed  a  well-marked 
grooye  from  the  oral  to  the  spinous  foramen,  and  the  tip  of  the  spina 
angnlaris  was  nearly  separated  from  its  base  by  a  suture. 

2nd.  The  presence  of  a  tooth  on  the  external  pterygoid  plate 
(figs.  6  u\  as  the  only  ossified  part  of  the  ligament ;  this  I  have  seen  very 
laj^,  and  in  one  negro  skull  (tribe  unknown)  from  the  Gold  Coast,  it 
appeared  as  a  round  tubercle  near  the  base  of  the  external  pterygoid 
plate,  but  separate  from  that  plate.  Several  instances  of  this  tooth 
were  coexistent  with  a  very  thin  oblique  lamellar  septum  between 
the  oval  and  spinous  foramina,  and  in  one  case  the  two  foramina  were 
not  separated,  while  on  the  right  side  of  another  the  oval  foramen 
communicated  with  the  pterygo-sphenoidal  fissure.  The  spinous 
foramen  in  another  specimen  was  in  the  line  of  the  spheno-petrosal 
suture.    Cases  of  this  kind  occurred  in  twenty  skulls. 

3rd.  Cases  of  the  presence  of  a  second  distinct  tooth  on  the 
pterygoid  plate.  This  is  noticed  in  Theile's  Muskellehre,  p.  68, 
where  such  a  tooth  may  be  below  the  primary  one,  is  always  flatter 
and  weaker,  and  rarely  has  a  ridge  like  the  prominent  rib  on  the  inside 
of  the  ectopterygoid  plate,  which  crosses  the  upper  part  of  the  ptery- 
goid fossa  to  strengthen  the  primary  tooth ;  sometimes  a  second 
accessory  tooth  higher  than  the  primary  one  is  present,  but  this 
usually  coexists  with  the  spur  to  be  described  below  (No.  5),  and  is  for 
the  accessory  ligament.  The  lower  tooth  is  for  the  attachment  of  the 
external  pterygoid  muscle.  Cases  of  the  existence  of  this  second  tooth 
existed  in  nine  skulls. 

4th.  The  coexistence  with  the  fore-mentioned  tooth  or  teeth  of  a 
forward-directed  spur  on  the  spina  angularis  sphenoidalis  was  noticed 
in  eighteen  skulls :  sometimes  this  is  of  very  large  size,  projecting 
towards  the  pterygoid  tooth,  but  always  separated  by  an  interspace 
(figs.  1, 2,  18  j9).  This  very  often  existed  with  a  double  pterygoid  tooth, 
and  in  one  instance  wher^  it  was  present  there  was  no  pterygoid  tooth : 
in  one  case  there  was  no  spina  angularis  on  the  sphenoid,  but  a  process 
sundered  from  the  anterior  and  internal  end  of  the  vaginal  ridge  (spina 
petrosa)  took  its  place.  This  spina  petrosa  is  not  rare,  either  as  an  angle 
of  the  vaginal  ridge  or  as  an  independent  spur,  and  it  often  contributes 
with  the  spina  angularis  to  give  origin  to  the  internal  lateral  ligament  of 
the  lower  jaw. 

5th.  The  existence  of  a  spina  accessoria  external  to  the  foramen 
ovale,  and  separated  from  the  spina  angularis  by  the  foramen  spinosum, 
has  been  before  referred  to  as  giving  attachment  to  the  ligamentum  acces- 
Borium  pterygo-spinosum  (figs.  1,  2,  9  a),  and  it  may  be  present  and  dis- 
tinct even  though  the  two  ligaments  are  united.  This  is  a  very  frequently 
present  spine,  as  it  exists  in  forty-one  skulls.  I  have  even  found  this 
present  in  the  skull  of  a  three-year-old  child.  In  some  of  these  it  was 
only  present  as  a  minute  rudiment,  but  in  others  it  was  long,  and  formed 
nearly  a  loop  with  a  long  pterygoid  tooth.  In  a  Chinook  skull  this 
coexisted  with  a  fine  lameUary  septum  between  the  foramina  ovale  and 
spinosum.  In  a  Mandingo  skull  it  coexisted  with  a  strong  spina  petrosa. 


204  Proceedings  of  the  Royal  Irish  Academy. 

taking  the  place  of  the  spina  angularis.  In  a  Melanesian  aknllfrom 
Chatham  Island  it  coexisted  with  a  fossa  pterygoidea  externa,  protected 
by  a  strong  processus  pterygoideus  accessorins  (the  same  fossa  I  have 
seen  in  the  skull  of  a  negro,  and  I  have  referred  to  it  elsewhere) 
(fig.  12  A). 

6th.  This  spina  sphenoidalis  accessoria  may  coexist  with  a  forward 
directed  tooth  on  the  spina  angularis,  and  this  exists  in  thirteen  skulls. 
In  one  of  these,  the  angular  tooth  is  pierced  externally  by  the  middle 
meningeal  artery.  These  two  spurs  often  rise  as  sharp  peaks,  one  in 
front  and  the  other  behind  the  foramen  spinosum,  so  as  to  give  the 
appearance  as  if  the  foramen  bored  through  the  spine ;  this  occurs 
in  several  crania,  among  others  in  one  Australian,  one  from  Circassia, 
and  one  found  embedded  in  plaster,  at  Sinai.  Sometimes  the  apices 
of  the  two  spines  are  joined  by  a  bridge  (that  is,  the  band  of  union 
which  forms  the  posterior  part  of  the  connexion  between  the  ligamen- 
tum  ptcrygo-spinosum  and  the  accessory  ligament  [when  these  are 
united],  becomes  ossified),  and  then  there  are  two  external  outlets  for 
the  foramen  spinosum,  an  outer  (larger  and  transmitting  the  artery) 
and  an  inner,  smaller,  and  usually  transmitting  the  nervus  spinosus 
(fig.  7  a').  This  may  coexist  with  a  double  tooth  on  the  ecto-pterygoid 
process,  but  if  so  the  second  tooth  is  generally  the  lower,  musciilary 
one. 

7th.  Cases  of  the  formation  of  a  complete  bony  bridge  are  not  rare. 
Professor  Gruber  assigns  a  frequency  of  once  in  thirteen  to  fourteen 
skulls.  In  our  collection  we  have  nine  in  which  such  a  bridge  occurs 
on  both  sides,  five  in  which  it  is  present  on  one  side.  Thus  our  pro- 
portion is,  that  a  bilateral  bridge  exists  in  one  in  sixteen,  a  unilateral 
or  bilateral,  once  in  9.5  cases. 

Two  forms  of  this  bridge  exist  which  should  not  be  confounded : — 
1  st,  ossification  of  the  true  Hgamentum  pterygo-spinosum.  This  is  either 
simple,  forming  a  large  wide  arch  (not  a  common  form)  (fig.  9  Ip),  or 
compound,  coexisting  with  an  ossified  Hgamentum  pterygo-spinosum 
accessorium.  This  latter  form  is  the  commonest,  and,  as  the  two  liga- 
ments are  usually  united  for  a  good  part  of  their  extent,  so  the  bony 
arch  is  simple,  wide,  and  shows  its  double  nature  by  having  two  piers 
at  its  hinder  end,  one  continuous  with  the  spina  accessoria,  one  with 
the  true  spina  angularis  (figs.  8,  1 1  o').  The  other  form  is  a  simple 
ossification  of  the  Hgamentum  accessorium  which  then  forms  a  closely 
adpressed  arch,  only  bridging  over  the  temporal  and  masseteric  nerve, 
(figs.  10,  13  a  «).  This  I  have  seen  weU  marked  in  an  Esquimaux 
skull  with  no  spina  angularis,  and  in  a  Chinook  skuU,  as  wdl  as  in 
several  Irish  crania. 

The  ossification  of  the  true  pterygo-spinous  Hgament  never  takes 
place  autogenously.  The  forward  end  ossifies  by  an  extension  into  it  of 
the  bony  matter  of  the  external  pterygoid  process,  while  the  hinder 
end  ossifies  as  an  offshoot  from  the  spina  angularis ;  hence  where  the 
two  bony  growths  coalesce  there  is,  in  nearly  every  case,  a  suture, 
which  I  have  very  seldom  seen  obHterated,  and  which  is  sometimes  den* 


Macalister — On  Ligamentum  Pterygo^noBum,        205 

tated  (fig.  9  x).  This  is  often  the  case  in  the  ligamentum  acceBBorinm 
also  (fig.  10  x),  but  here  complete  ossification  and  obliteration  of  the 
suture  at  the  point  of  junction  is  much  commoner,  so  that  the  arch 
becomes  sunple,  solid  (fig.  13). 

A  form  of  spurious  arcuation  may  be  produced  by  the  elongation 
and  convergence  of  the  two  ecto-pterygoid  teeth,  which  may  loop 
towards  each  other  in  an  arched  form,  and  may  even  touch,  leaving 
thus  a  round  hole  in  the  external  pterygoid  plate  (figs.  2,  4  «).  This 
when  present  transmits  an  anomalous  branch  of  the  intemal'maxillary 
artery. 

The  whole  trunk  of  the  internal  maxillary,  in  a  not  uncommon 
anomalous  course  under  the  external  pterygoid  muscle,  either  pierces 
below,  or  through,  or  under  the  ligament  of  Civinini,  so  that  when 
this  band  is  ossified,  it  is  not  uncommon  to  find  the  whole  trunk  of 
the  artery  passing  through  the  loops  of  the  bony  bridge.  Such  an 
arrangement  is  the  exact  repetition  of  the  course  of  the  artery  in 
Bodents  and  many  other  mammalian  orders ;  indeed  this  seems  the  only 
assignable  use  for  the  ligament,  to  protect  the  artery  from  the  pressure 
of  the  pterygoid  muscles.  In  Henle-Krause's  Handbuch  der  Gefass- 
lehre  des  Menschen,  p.  243,  Professor  Krause  describes  the  anomalous 
internal  maxillary  as  trasversing  sometimes  a  hole  in  the  lamina 
lateralis  processi  pterygoidi  ossis  sphenoidei  (external  pterygoid  plate), 
and  speaks  of  this  being  analogous  to  the  condition  in  the  rabbit.  The 
hole  referred  to  is  the  arch  of  th9  ligament ;  for  the  trunk  internal 
maxillary  artery  liever  passes  through  any  hole  in  the  outer  pterygoid 
plate  proper. 

In  a  Mandingo  skuU,  the  spina  angularis  is  double,  half  formed  of 
the  squamosal  element  of  the  anterior  lip  of  the  glenoid  cavity,  and 
half  of  the  sphenoid,  the  spheno-squamosal  suture  crossing  the  summit 
of  the  process,  and  this  coexists  with  a  foramen  spinosum  in  the  spheno- 
petrosal suture.  In  another  skull  the  tooth  on  the  pterygoid  plate  is  a 
tooth  on  the  outside,  not  on  the  hinder  margin  of  the  plate. 


206  Proceedings  of  the  Royal  Irish  Academy. 


XXXI. — On  a  Malfoemed  Coeoka   o?  EcHnrus  esculkhtus.      Bj 
H.  W.  MAcmrrosH,  B.  A.     (With  Plates  21  and  22). 

[Read  May  10, 1875.] 

The  remarkable  specimen  which  is  described  in  the  present  communi- 
cation has  lain  for  many  years  in  the  Museum  of  the  Dublin  Univer- 
sity, having  been,  as  I  am  informed  by  Professor  Dr.  Perceval  Wright, 
dredged  up  by  the  late  Dr.  Ball  off  the  coast  of  Youghal. 

I  had  often  noticed  it  in  the  course  of  my  museum  studies,  on  ac- 
count of  the  prominent  pouch  which  the  actinal  (oral)  aspect  presents, 
but  had  not  bestowed  more  than  a  casual  inspection  on  it  till  recently, 
when  its  many  peculiarities  so  forced  themselves  on  my  attention,  that 
I  requested  and  obtained  permission  of  Professor  Dr.  Macalister, 
the  present  Director  of  the  Museum,  to  place  a  short  description  of 
it  on  record. 

In  describing  the  present  specimen  I  shall  not  attempt  anything 
like  a  detailed  notice  of  all  its  peculiarities.  Such  a  proceeding 
would  be  but  of  little  value  or  interest,  and  a  mere  abstract  descrip- 
tion of  such  a  shell  would  convey  but  little  idea  to  the  mind ;  hence 
I  prefer  relying  on  the  drawings*  for  this  purpose,  and  will  only  indi- 
cate here  the  chief  features  of  interest. 

For  purposes  of  convenience  the  madreporic  plate — ^placed  pos- 
teriorly— ^and  corresponding  interambulacrum  will  be  numbered  I,  the 
next  genital  plate  on  the  left,  and  its  interam- 
bulacrum will  be  II,  and  so  on  horn,  left  to 
right ;  the  ocular  plate  and  ambulacrum  on  the 
immediate  left  of  the  madreporic,  will  be  1,  the 
next  on  its  left  2,  and  so  on  in  the  same  order ; 
and,  since  each  area  has  a  double  series  of  plates, 
these  will  be  called  I »,  1 5,  &c.,  or  1  «,  1  h,  &c., 
respectively.  I  adopt  this  method  simply  for 
convenience  and  not  with  any  reference  to  the 
views  put  forward  by  Professors  A.  Agassiz  or 
Loven,  as  to  the  position  of  the  madreporic  plate. 

Looked  at  as  a  whole,  the  corona  is  seen  to  be  considerably  flat- 
tened on  the  madreporic  side,  which  \a  produced  on  the  actinal  surface 
into  a  sort  of  boss  or  pouch  (Plate  21,  fig.  2).  The  mouth  is  eccentric, 
displaced  to  the  lower  left-hand  side ;  the  auricles  are  normal.  In  the 
abactinal  system,  plate  I  (madreporic),  is  unsymmetrical,  being  pro- 
longed at  the  upper  l^hand  comer,  and  has  but  little  of  the  character- 


•  Whieh  have  been  all  taken  under  the  camera  lucida.  As  the  outlines  of 
the  plates  are  the  most  striking  part  of  the  corona,  I  have  drawn  them  as  accurately 
as  I  could,  and  have  therefore  laid  down  the  tubercles  almost  orthographically. 


Mackintosh — On  a  Malformed  Corona  of  Echinus.       207 

istic  granulation ;  plate  II.  is  very  much  elongated  anteroposteriorly,  and 
the  orifice  for  the  genital  duct  has  disappeared ;  plate  III.  presents 
the  reverse  condition,  being  broader  than  deep,  and  has  its  genital 
aperture ;  plates  IV.  and  Y .  are  but  slightly  altered.  The  ocular  plates 
are  scarcely  changed  in  form,  with  the  exception  of  plate  1,  which  is 
considerably  elongated  at  the  lower  left-hand  comer.  The  anal  sys- 
tem corresponds  in  outline  to  the  abactinal,  being  drawn  out  from 
before  backwards. 

In  the  corona  the  alterations  are  mainly  confined  to  ambulacrals 
1  and  2,  and  to  the  corresponding  interradia,  and  of  these,  interambu- 
lacrum  la  is  scarcely  changed,  being  merely  curved  to  the  right 
a  little  more  than  usual ;  1 5  is  a  good  deal  altered,  its  fourth  plate 
(from  the  top)  seems  to  be  made  up  of  two  fused  together ;  and  the 
twelfth  and  succeeding  plates  are  very  much  elongated  towards  the 
left  side,  and  seem  to  include  the  greater  part  of  the  actinal  boss. 
Ambulacrum  1  seems  to  be  only  represented  by  the  short  series  of  pores 
seen  in  Plate  22,  fig.  4,  which  terminates  almost  at  the  summit  of 
the  boss,  and  ihe  perforations  of  which  have  no  very  definite  arrange- 
ment. This  ambidacral  area  is  thus  altogether  included  in  I  &.  The 
next  ambulacrum  is  a  curious  one.  It  begins  normally,  both  in 
arrangement  and  position,  but  soon  bifurcates,  one  division  going  up 
to  the  abactinal  system  to  form  ambulacrum  2,  of  which  2  Hs  per-, 
fectly  unaltered,  but  2  a  is  remarkable  for  the  exceedingly  scattered 
disposition  of  its  pores  (Plate  21,  fig.  2),  some  of  which  are  placed 
well  within  interambulacrum  U  i,  whilst  others  are  situated  in  the 
middle  line  of  their  own  radium.  The. other  half  of  this  ambulacrum 
runs  up  to  a  short  distance  above  the  ambitus  ^equator  of  the  corona), 
where  it  abruptly  terminates,  thus  circumscribing  interambulacrum 
II.,  which,  ending  in  a  point  a  little  below  the  ambitus,  fails  to  reach 
the  actinal  opening,  and  assumes  a  striking  petaloid  appearance. 
There  are  thus  but  four  ambulacral  areas  reaching  the  abactinal 
system.  No.  1  being  deficient,  and  its  place  occupied  by  the  remark- 
able congeries  of  plates  shown  in  the  figures. 

The  dimensions  of  the  corona  are  as  follows : — 

Bound  the  ambitus , 15  inches. 

Dextro-sinistral  circumference, 13i    „ 

Antero-posterior  circumference,  ....  13  ^, 
Depth  (from  abactinal  to  actinal  orifice), .  .  3^^  ,, 
As  regards  the  cause  of  this  curious  malformation  it  is  difficult  to 
speak  absolutely.  The  altered  side  of  the  corona,  though  presenting 
more  or  less  of  an  undulating  appearance,  has  no  sharp  depressions 
such  as  might  be  caused  by  fracture  and  repair ;  if  this  has  taken 
place  it  has  been  unusually  evenly  done,  for  it  is  seldom  that  the 
calcareous  parts  of  Echinoids  are  repaired  without  showing  very  mani- 
fest tokens  of  the  change.  The  flattening  of  the  altered  side,  and 
the  presence  of  the  actinal  boss,  suggest  the  idea  that  the  lateral 
growth  of  the  test  was  limited  by  its  surroundings,  and  had  to  take 


208  Proceedings  of  the  Boyal  Irish  Academy. 

place  in  a  downward  direction — a  supposition  whicli  perhaps  wt)uld  be 
strengthened  by  the  absence  of  ambidacra  on  the  flattened  side.  I  am 
free  to  confess,  however,  that  this  solution  is  not  satisfactory,  for  it 
would  be  a  matter  of  no  little  difficulty  to  arrange  the  surroundings  so 
as  to  produce  the  given  result,  and  hence  I  am  fain  to  keep  clear  of  the 
cloud-begirt  regions  of  hypothesis,  and  limit  myself  to  the  simiple 
record  of  facts. 

Malformed  specimens  of  Echini  have  been  described  by  the  fol- 
lowing : — 

Philippi,  "Weigmann's  Archiv  fur  Naturgeschichte,  1837."  I 
have  not  been  able  to  consult  this  paper,  as  the  volume  of  this 
Archiv  for  1837  is  not  in  any  of  the  Dublm  libraries. 

Einahan  and  Du  Noyer,  **  Proceedings  of  the  Dublin  Natural  His- 
tory Society,"  vol.  ii.,  1 857.  The  specimen  seems  to  combine  the  pores 
and  tubercles  of  Strongylocentrotua  lividus,  with  the  actinal  system  of 
Echinus  eseulentus. 

T.K.Stewart,  ''Annals  and  Magazine  of  Natural  History,  drd 
series,  Yol.  v.,  1860."  The  malformation  is  chiefly  in  the  abactinal 
system,  the  corona  being  but  slightly  altered. 

Donitz,  "Eeichert  und  Du  Bois  Reymond's  Archiv,  1866."  The 
malformation  consists  in  the  almost  total  disappearance  of  one  of  the 
five  interambulacra,  and  a  corresponding  change  in  shape  of  the  corona. 


M'Nab — Bemarks  on  the  Leaves  of  certain  Coni/erts.     209 


XXXII. — KmffATtTB    OK    THE    StBX7CI17BB    OF  THE  LEATES    OP  CEETAIN 

CoviFSRM.     By  W.  R.  M'Nab,  M.  D.,  Edinburgh,  Professor  of 
Botany,  Eoyal  College  of  Science  for  Ireland.    (With  Plate  23.) 

[Read  June  14, 1875.] 

hf  a  ThesiB  which  was  presented  to  the  Faculty  of  Science,  Paris, 
and  published  last  year,  Br.  C.  E.  Bertrand  describes  the  comparative 
anatomy  of  the  stems  and  leaves  of  the  Gnetacese  and  Conifers.  In 
his  descriptions  Bertrand  gives  anatomical  characters  by  which  sub- 
genera may  be  readily  separated,  and  also  gives  tables  by  which 
to  identify  the  species.  Believing  that,  in  one  or  two  respects, 
Bertrand  has  come  to  erroneous  conclusions,  I  determined  to  re-inves- 
tigate certain  points  which  I  considered  of  importance.  In  doing  so 
I  had  the  great  advantage  of  having  access  to  the  collection  of  Coni- 
ferse  at  the  Eoyal  Botanic  Garden,  Edinburgh,  where  most  of  the 
rare  and  valuable  North  American  species  are  carefuUy  cultivated. 
We  are  certainly  much  indebted  to  Bertrand  for  pointing  out  that 
valuable  characters  can  be  got  by  anatomical  investigation  of  the 
leaves  of  Pines.  To  the  nurseryman  who  has  chiefly  to  do  with 
small  plants  without  cones,  any  good  method  of  determining  species  by 
the  foliage  must  be  welcome.  While,  however,  I  acknowledge  the 
value  of  such  anatomical  characters,  I  do  not  think  we  can  place  im- 
plicit confidence  iu  them  alone;  but  that,  when  taken  along  with 
other  characters,  they  are  of  the  highest  value.  It  is  chiefly  by 
making  transverse  sections  of  the  leaf  that  the  investigation  is  to 
be  carried  on.  Yery  thin  slices  are  to  be  taken  from  the  middle 
of  the  leaf,  care  being  taken  to  have  the  sections  in  the  proper 
plane.  All  the  sections  I  have  examined  were  placed  at  once  in  dilute 
glycerine ;  and,  in  nearly  all  cases,  the  perfectly  fresh  leaf  was  used. 
The  chief  points  to  observe  in  the  sections  are: — 1st,  the  nature  of 
the  flbro- vascular  bundles  or  midrib ;  2nd,  the  sheath  of  the  flbro- 
vascnlar  bundles ;  Srd,  the  resin  canal  or  canals ;  4th,  the  thickened 
cells  or  hypoderma  belonging  to  the  ground-tissue,  and  placed  below 
the  epidermis,  but  not  belonging  to  it ;  5th,  the  parenchyma  of  the 
ground-tissue ;  6th,  the  epidermis,  with  its  cuticle ;  and  7th,  the 
arrangement  of  the  stomata;  this  last,  however,  requiring  the  examina- 
tion of  the  upper  and  under  surfaces  of  the  leaf  iu  addition. 

My  attention  was  first  directed  to  Bertrand' s  sub-genus  Tsuga, 
which  includes — Finns  Pationiana,  eanadensiSf  Mertensiana,  Sre.  I 
think  it  is  best  to  follow  Parlatore  in  his  definition  of  the  genus  Pinus ; 
but  I  would  limit  Parlatore's  section  Tsuga,  and  use  it  in  tiie  restricted 
sense  in  which  Carri^re  andBertrand  employ  it.  In  Parlatore's  Conif  ersB 
(Be  Candolle  Prod.,  vol.  xvi.,  pars  2),  the  section  VI.  Tsuga  Endl. 
Pari,  is  used  to  include : — ^Tsuga  Carr.,  Keteleeiia  Carr.,  and  Pseudo- 

X.  I.  A.  FBOC,  ssB.  n.,  VOL.  n.,  Bcznrcz.  2  F 


210  Proceedings  of  the  Royal  Irish  Academy. 

tsuga,  Carr.  Pinus  Douglasii  belongs  to  Carri^re's  Fseudotsuga,  and 
Pinus  Fortunei  to  his  Keteleeria.  Both  P.  Douglasii  and  P,  Fortunei 
must  be  placed  in  Carriere's  Fseudotsuga. 

The  section  Tsuga  is  well  characterised  by  the  presence  of  a  single 
median  resin  canal,  which  is  placed  below  the  single  central  fibro- 
vascular  bundle  forming  the  midrib;  by  the  flattened  leaves  bifaiiously 
placed ;  and  lastly,  by  the  presence  of  well  marked  cushions  supporting 
the  leaves. 

Five  species,  as  described  by  Parlatore,  belong  to  the  restricted 
section  Tsuga,  viz. : — 

106.  P.  Tsuga  Ant. 

107.  P.  canadensis  Linn. 

108.  P.  Mertensiana  Bougaid. 

109.  P.  dumosa  Don. 

110.  B.  Pattoniana  Pari. 

To  this  I  have  one  to  add,  viz.,  P.  Hookeriana,  the  Abies  Hooker- 
iana  of  A.  Murray. 

Bertrand  only  distinguishes  four  species  by  anatomical  characters, 
and  gives  the  following  synoptic  table  of  these  characters : — 

Stomata  on  the  upper  surface  of  the  leaf; 

Margin  entire ;  no  hypoderma,  .  P.  Hooxebiaha.. 

No  stomata  on  the  upper  surface  of  the  leaf ; 
Margin  of  leaf  serrulate ;   hypoderma,  .     P.  CAirASEKSis. 

Margin  entire,  (g°^^Xl'^       !        !    ?!  JSSr" 

Bertrand  further  gives  the  following  table  of  the  synonomy  and 
distribution  of  the  species : — 

Picca  (Tsuga)  Hookeriana  Carr.,  Northern  California. 

Syn.   Abies    Pattoni   Jeff.     A.   Hookerii     Hort.     A.    WilUamsoiui 

Newbury. 
Picea  (Tsuga)  canadensis    Link.      (T.  Mertensiana  does  not  differ 

anatomically  from  T.  canadensis).     Bocky  Mountains. 
Syn.    Abies    canadensis    Mich.      iHnus     Americana    Du  Boi.     P. 

canadensis  Linn. 
Picea  (Tsuga)  Bninoniana  "Wall.     Southern  China. 
Syn.    Abies    dumosa     Loudon.     A.   cedroides    Griff.      Micropeuce 

Bninoniana    Spach.     P.decidua.   Wall. 
Picea  (Tsuga)  Sieboldii  Carr.     Japan. 
Syn.     Pinus  Tsuga  Ant. 

From  my  examination  of  the  species  of  the  section  Tsuga,  I  find 
that  Hookeriana  and  Pattoniana  are  distinct ;  but  I  can  refer  neither 
of  them  to  Bertiand's  Hookeriana.    Probably  his  Hookeriana  is  our 


M*Nab — Bemarks  on  the  Leaves  of  certain  Coni/era,      211 

Fattoniana ;  but  in  all  specimens  tliat  liaTe  come  under  my  notice 
the  hypoderm  is  developed,  while  Bertrand  distinctly  says,  **  Pas 
d'hypodenn."  Then  the  specimens  of  canadensis  and  Mertensiana 
examined  by  me  are  quite  distinct.  In  this  case  I  think  that  Bertrand 
has  described  Mertensiana  for  canadensis.  Lastly,  in  his  description 
of  Brunoniana  and  Sieboldii  we  are  slightly  at  yanance. 

The  forms  about  which  the  greatest  confusion  has  existed  are 
Hookeriana  and  Fattoniana.  Both  are,  at  first  sight,  very  similar 
in  habit  and  in  appearance,  while  their  cones  are  also  exceedingly  close. 
They  are,  however,  readily  separated  by  the  structure  of  the  leaf.  In 
Hookeriana  the  resin  canal  is  separated  from  the  fibro-vascular  bun- 
dles by  a  few  parenchymatous  cells,  containing  chlorophyll — a  charac- 
ter which  does  not  occur  in  any  of  the  other  species.  The  leaf  is  also 
thicker,  more  tetragonousthan  Fattoniana ;  the  margins  of  the  leaf  are 
entire,  while  in  Fattoniana  they  are  distinctly  serrulate  near  the 
apex.  Both  the  species,  however,  agree  in  having  stomata  on  the 
upper  as  well  as  on  the  under  surface  of  the  leaf  ^  In  Hookeriana  the 
hypoderm  forms  a  nearly  continuous  row  of  cells  beneath  the  whole 
epidermis,  giving  such  an  appearance  as  might  almost  be  produced  if 
the  epidermis  consisted  of  a  double  instead  of  a  single  layer  of 
cells. 

Taking  all  the  characters,  I  would  give  the  following  table  by 
which  to  separate  the  different  species : — 


I.  Young  shoots  hairy. 

A.  Besin  canal  separated  from  the  sheath 
of  the  fibro-vascular  bundles  by  one  or 
two  layers  of  large  chlorophyll-bear- 
ing cells ;  leaf  flatly  tetragonous,  the 
hypoderma  nearly  continuous  around 
the  whole  leaf ;  stomata  on  both  sur- 
faces  


1.  T.  HoozsBiAirA. 


B.  Besin  canal  in  contact  with  sheath  of 
fibro-vascular  bundles. 

1.  Stomata  on  both  sides  of  leaf; 
hypoderma  well  developed. 

2.  Stomata  on  under  surface  of  leaf 
only. 

a.  No  hypoderma;  margin  of 
lea£  rough ;  apex  obtuse. 

h.  Hypoderma  at  margins  of  leaf, 
and  above  midrib ;  margin  of 
leaf  ciliate ;  apex  obtuse. 


2.  T.  Fattoniawa. 


8.   T.  CAlTADEirSIS. 


4.  T.  Mkbtxnsiana. 


212  Proceedings  of  the  Royal  Irish  Academy. 

c.  HypodennaatmarginBof  leaf, 
and  at  eaoh  side  of  the  resm 
canal ;  margins  of  leaf  slightly 
reflezed ;  serrulate ;  apex  olh- 
tuse, 5.  T.  BnOTOiriAiri.. 

II.  Young  shoots  glabrons;  hypoderma  at 
margins  of  leaf  only;  margin  of  leaf 
entire;  apex  emarginate,  sometimes  ob- 
tose;  stomata  on  under  surface  of  leaf 
only •    6.  T.  Sixboldh. 

1.  PinuB  (Tsuga)  Sookeriana. 

Abies  Hookeriana  A.  Murray,  Edinburgh  ITew  Philosoph. 
Journal,  1855,  p.  289. 

Tsuga  Hookeriana  Carr.  f  not  of  Bertrand. 

Shoots  hairy ;  leaves  four  to  seven  lines  in  length,  irregularly 
bif  ariouB ;  margin  entire ;  apex  obtuse ;  two  sides  of  leaf  similar  dark 
green,  with  four  to  six  rows  of  stomata  on  each  side  of  the  middle 
line.    Plate  23,  fig.  1. 

2.  Pinus  (Tsuga)  Pattoniana. 

Abies  Pattoniana  Jef^.  Oregon  Bot.  Exped.  3. 

Shoots  hairy;  leaves  six  to  nine  lines  long,  irregularly  bifarious;  mar- 
gin denticulate  near  the  obtuse  apex ;  upper  side  yellowish  green,  with 
from  two  to  four  rows  of  stomata  on  each  side  of  the  slightly  marked 
central  furrow,  beneath  with  six  to  seven  rows  of  stomata  on  each  side 
of  the  middle  line.    Plate  23,  fig.  2. 

The  forms  cultivated  in  the  Edinburgh  Botanic  Garden,  under  the 
names  of  Abies  Parryana  and  Abies  Huiburyana,  cannot  be  separated 
by  any  characters  from  P.  Pattoniana.  This  is  not  Pinus  Pattoniana 
of  Parlatore,  as  he  includes  both  this  species  and  P.  Hookeriana. 

3.  Pinus  (Tsug»)  canadensis  lann.  Parlatore. 

Shoots  hairy ;  leaves  six  to  nine  lines  long  in  two  rows ;  margins 
rough ;  apex  obtuse ;  upper  side  dark  green,  with  a  central  fuixow, 
beneatii  with  eight  or  nine  rows  of  stomata  on  each  side  of  the  promi- 
nent resin  canaL    Plate  23,  fig.  3. 

4.  Pinus  (Tsuga)  Mertensiana  Bougard.    Parlatore. 

Shoots  hairy ;  leaves  four  to  seven  lines  long  in  two  rows ;  margins 
eiliate ;  apex  obtuse ;  upper  side  dark  green,  with  a  central  furrow, 
beneath  with  eight  or  nine  rows  of  stomata  on  each  side  of  the  middle 
line,  where  the  hypoderm  is  developed.    Plate  23,  fig.  4. 

The  forms  cultivated  in  the  Edinburgh  Botanic  Gardens,  under 
the  names  of  Abies  Albertiana,  Abies  Bridgesii,  and  Abies  Williamsonii. 
cannot  be  separated  by  any  characters  from  P.  Hertensiana, 


M'Nab — Bemarka  on  the  Leaves  of  certain  Coniferm.      213 

Farlatore  gives  A.  Williamsonii  as  a  Bynoiiyin  of  his  F.  Fattomana, 
while  Bertrand  gives  Williamsonii  as  a  synonym  of  his  T.  Hookexiana. 

5.  Finns  (Tsaga)  Bntnoniana  Wall. 

Finns  dnmosa  Don.  Farlatore. 

Shoots  hairy ;  leaves  twelve  to  fourteen  lines  long  in  two  rows ; 
deciduous;  margins  slightly  reflexed  ;  serrulate;  apex  obtuse;  upper 
side  grass  green,  with  a  central  furrow,  beneath  with  a  band  of  nine 
or  ten  rows  of  stomata  placed  close  to  each  side  of  the  central  carina, 
Flate  23,  fig.  5. 

6.  Finns  (Tsuga)  Sieboldii  Carr. 

Finns  Tsuga  Ant.  Farlatore. 

Shoots  glabrous ;  leaves  eight  to  ten  lines  long  in  two  rows ;  margin 
entire ;  apex  emarginate,  sometimes  acute ;  upper  side  dark  green, 
with  a  central  farrow,  beneath  with  a  band  of  six  to  eight  rows  of 
stomata  on  each  side  of  the  middle  line.    Flate  23,  fig.  6. 

In  conclusion,  I  have  to  tender  m^  best  thanks  to  Dr.  Moore, 
Glasnevin,  for  kindly  furnishing  me  with  specimens  from  Glasnevin 
Gardens ;  while  to  my  father  I  am  chiefly  indebted,  as  he  furnished 
me  with  specimens  of  all  the  forms  cultivated  in  the  Boyal  Botanic 
Garden,  Edinburgh. 


214  Proceedings  of  the  Boyal  Imh  Academy, 


yXXTTT. — Ov  Two  Dissdolab  Fobxb  of  PfiomHUo  ForoHEs.  By 
ALxxAjmEB  Macauster,  M.B.,  Frofessor  of  Comparatiye  Anatomy, 
Dublin  Univereity.    (With  Plate  24.) 

[Bead  June  14,  1876.] 

Ik  a  paper  published  in  Yirchow's  Archiy.,  1874,  Band.  60,  p.  66, 
Prof.  Waldeyer  of  Breslau  giyes  a  resumS  of  all  the  cases  of  post- 
abdominal  pouches  of  which  he  has  found  records,  and  from  these 
data  proceeds  to  classify  these  pouches  accoiding  to  their  anatomical 
position,  and  to  suggest  the  probable  cause  of  the  formation  of  each 
species.  His  experience  agrees  with  that  of  eyeiy  practical  anatomist, 
that  the  neighbourhood  of  the  caecum  is  that  which  is  most  fertile  ia 
irregolarities,  as  he  catalogues  four  species  which  occur  in  this 
locality. 

Haying  seen  a  yery  large  number  of  these  pouches,  I  was  early  led 
to  belieye  that,  although  it  is  usefi^  for  conyenience,  to  classify  these, 
yet  scarcely  two  of  these  perityphlic  pouches  are  alike.  This  is  what 
one  might  expect  from  a  few  moments'  thought  on  the  remarkable  and 
yariable  changes  to  which  this  region  is  exposed  in  the  course  of  the 
deyelopment  and  descent  of  the  caecum,  and  hence  almost  eyery  case 
that  occurs  has  its  own  features  of  interest. 

In  the  present  yolume  of  the*  Proceedings  of  this  Academy  one 
yariety  of  pouch  was  described  by  Mr.  Leeper,  under  the  name  of 
recenus  rstroomealiif  a  pouch  which,  though  belonging  to  a  genus  of 
f 0SS8B  similar  to  others  described  elsewhere,  yet  had  strongly  marked 
indiyidual  features  of  its  own.  A  case  resembling  this  in  some  features 
occurred  in  an  old  emaciated  female  subject  dissected  at  the  end  of  the 
last  session  in  the  Anatomy  room  of  the  Dublin  TJniyersity.  This 
subject  showed  a  faint  superior  ilio-c88cal  pouch,  whose  floor  was 
formed  by  tiiie  layer  of  peritoneum  at  the  inferior  and  left  end  of  the  root 
of  the  mesentery,  which  was  attached  to  the  anterior  surface  of  the  psoas 
muscle.  There  was  no  inferior  ilio-c®cal  fossa,  and  the  mesentorio- 
lum  was  dender,  not  bounding  any  ilio-cscal  recess  either  aboye  or 
below  it,  nor  was  there  a  trace  of  a  sub-caecal  fossa.  The  descending 
colon  was  yeiy  long,  and,  as  is  always  the  case  under  such  circum- 
stances, the  end  of  tiie  c»cum  was  pu^ed  well  forwards,  lying  on  the 
anterior  wall  of  the  abdomen,  the  fundus  of  the  caecum  being  well 
turned  forwards,  and  the  peritoneal  coyering  of  this  part  of  the  large 
intestine  was  exceedingly  imperfect,  the  serous  membrane  passing  as  a 
tense  lamina  from  the  sides  of  the  caecum  to  the  sides  of  the  abdominal 
wall.  The  ascending  colon  on  the  leyel  of  the  crest  of  the  ilium  was 
displaced  backwards  in  a  knuckle-like  fold,  to  such  a  depth  that  the 
middle  part  was  quite  buried  in  a  backwards  and  inwards-reaching  sac. 

•  jinUa,  p.  79. 


Macai.i8Teb — On  two  Forms  of  Perityphlic  Pouches.      215 

On  pulling  this  out,  a  large  pouch  was  displayed,  burrowing  behind  the 
psoas  muscle  as  far  inwards  as  the  yertebral  column  opposite  the 
transyerse  process  of  the  fifth  lumbar  yertebra,  haying  a  strong  ilio- 
lumbar Hgunent  aboye  it,  and  being  crossed  at  its  upper  part  pos- 
teriorly by  the  ilio-hypogastric  nerye,  and  a  little  lower  by  the  ilio- 
inguinal. A  separate  slip  of  the  psoas  muscle  from  the  transverse 
process  of  the  fifth  liunbar  yertebra  projected  into  the  fundus  of  the 
sac.  The  mouth  of  this  fossa  looked  upwards,  and  a  little  forwards 
and  outwards,  and  was  bounded  in  part  by  a  crescentic  fold  of  iliac 
fascia  from  the  anterior  surface  of  the  psoas  magnus  (there  was  no 
psoas  paryus),  passing  outwards  to  the  front  of  the  iliacus.  So  deep 
was  this  pouch,  that  the  index  finger  introduced  into  it  could  be  im- 
bedded to  the  base  of  the  second  joint,  and  could  touch  the  back  of  the 
common  iUac  artery  at  its  bifurcation  behind  the  psoas.  Pully  three 
and  a  half  inches  of  the  colon  were  sunk  into  this  recess,  and  held 
there  by  the  reflection  of  peritoneum  from  the  ascending  lumbar  meso- 
colon outwards  to  the  wall  of  the  fossa.  The  pouch  had  a  distinct 
flooring  of  iliac  fascia. 

Co-existing  in  this  subject  was  a  good  lai^e  intersigmoid  pouch 
"with,  as  usual,  no  fascial  relations,  but  a  crescentic  fold  of  fascia  formed 
a  shallow  retrosigmoid  fossa  like  that  described  by  Leeper.  There  was 
a  yery  strong  and  large  cysto-hepato-colic  ligament.  Pully  fiye  inches 
of  large  intestine  stretched  from  the  lower  Kp  of  the  pouch  to  the 
fundus  of  the  caecum,  and  at  the  inner  side  of  the  pouch  the  peritoneum 
was  raised  and  rendered  prominent  directly  internal  to  the  inyoluted 
portion  of  the  colon,  by  die  prominent  inferior  angle  of  the  duodenum. 
In  comparing  this  case  with  the  already  described  instances  of 
csecal  fossse,  it  will  be  seen  to  resemble  most  closely  the  three  cases 
recorded  by  A.  Biesiadecki  of  Cracow,  in  the  Untersuchungen  aus 
dem  Pathologische-Anatomische  Institut  in  Erakau,  Wien,  1872.  The 
I0S88B,  which  this  author  grqups  under  the  name  fossa  iliaco-subfascialis, 
had  this  in  common  with  it,  that  they  were  bounded  by  a  prominent 
fold  of  the  iliac  fascia,  that  they  were  between  the  psoas  and  iliacus, 
that  the  iliacus  muscle  was  more  or  less  behind  it ;  his  cases  were  also 
distinctly  beneath  the  lower  edge  of  the  iliac  fascia,  which  was  strength- 
ened by  the  fibres  of  the  psoas  paryus.*  A  case  of  csecal  fossa  is 
described  by  Huschke,  in  which  a  fold  of  iliac  fascia  is  referred  to ; 
but  this  is  by  no  means  identical  with  either  Leeper's  pouch  or  the 
one  described  aboye,  as  Huschke's  is  circumstanced  yery  differently, 
for  this  author  describes  haying  found,  by  an  exaggeration  of  the 
normal  descent  of  the  intestine,  a  falciform  fold  formed  by  the  perito- 
neum and  the  fascia  iliaca,  yery  prominent,  upwards  and  forwards,  form* 

*  £yen  when  thifl  muscle  does  not  exist  as  such,  a  strong  band  of  fibrous  tissue 
tiivngthens  the  iliac  fascia  and  passes  outwards  across  the  iliacus  at  its  site  of  in- 
sertion, while  a  slip  of  strengthened  aponeurosis  lies  in  the  situation  of  its  tendon 
on  the  inner  side  of  the  psoas  magnus.  These  should  be  regarded  as  rudime&tal 
oxgani. 


216  Proceedings  of  the  Royal  Irish  Academy.  I 

ing  a  sort  of  bed  for  the  cncnm  (HuBchke's  Eingeweidelelirei  p.  79 ;  i 

Jourdan's  TraoB.  1845,  p.  90) ;  here  the  fold  is  produced  by  the  descent  i 

of  the  csBcuniy  and  the  intestine  accnratelj  fits  the  fossa.  In  speaking 
also  of  the  peritoneal  investment  of  the  cfficum,  he  says,  that  the  begin-  ' 

ning  of  the  right  colon  has  often  a  peritoneal  ligament  attached  (right  colic  I 

ligament  of  Hensing,)  which  raises  itself  from  the  right  iliacus  mnsde,  I 

and  often  forms  a  fossa  of  which  the  opening  receives  the  colon ;   this  | 

he  calls  the  c»cal  ligament.     The  marks  whereby  this  is  distinguished  , 

are  its  accurately  corresponding  to  the  csBcum,  and  being  formed  by 
that  intestine,  and  bounded  externally  by  Hensing's*  ligament. 

Waldeyer  f  cites  a  case  of  the  existence  of  what  he  names  a  fossa  I 

esBcalis ;  but  it  is  difPerent  from  either  Huschke's,  Leeper's,  or  mine,  I 

and  also  received  the  end  of  the  csecum.  It  occurred  in  a  girl  who  died  i 

of  acute  Endocarditis;  its  right  boundary  was  Hensing^s  ligament 
(Huschke's  cecal  ligament) ;  its  left  fold  went  to  the  angle  of  fusion 
of  both  plicffi  which  bound  the  ilio-caecal  recess.  We  wHl  have  more 
occasion  to  notice  this  instance  presently.  Langer  \  has  also 
described  an  instance  in  a  young  soldier  which  corresponds  closely 
to  that  given  by  Waldeyer,  and  which  also  corresponded  to  the 
fundus  of  the  well-descended  cascum ;  but  like  the  former  case  there  is 
no  record  of  a  fold  of  iliac  fascia  as  related  to  the  sac,  although  both 
Langer  and  Waldeyer  were  acquainted  with  Huschke's  description. 
Treitz  §  notices  cases  likewise'  of  its  occurrence  in  children  and  young 
persons,  its  occurrence  being  due  to  the  descent  of  the  caecum — 
**  durch  das  Herabsinken  des  Cecum  wird  in  der  That  manchmal  das 
Peritoneum  der  Fossa  iliaca  etwas  eingestiilpt  und  bildet  eine  sehr 
flache,  nach  aufwarts  sehende  Tasche,  in  die  sich  das  Cocum  legt." 

The  instance  described  by  Leeper  differs  from  all  these  in  having 
no  relation  to  the  caecum  or  to  any  intestine,  and  being  a  primary  fold 
of  the  iliac  fascia  clothed  by  peritoneum. 

My  specimen  is  likewise  peculiar  in  its  extending  inwards  behind 
the  psoas,  in  its  lower  position  regarding  the  ilium,  in  its  having  a 
perfect  flooring  of  iliac  fascia,  and  in  its  co-existence  with  no  ligament 
of  Housing. 

The  same  subject  had  a  large  subsplenic  fossa,  and  the  left  obtu- 
rator foramen  had  a  shallow  peritoneal  involution  capable  of  receiving 
the  tip  of  the  middle  finger,  and  about  three  quarters  of  an  inch  deep. 
This  ran  inwards  and  forwards  under  the  pectineus,  and  lay  over  the 
obturator  vessels  and  nerves. 

The  causation  of  these  pouches  in  this  subject  is  also  a  point  of  con- 
siderable interest ;  the  old  woman  was  a  victim  to  tight  lacing,  and  pre- 
sented many  of  the  pathological  phenomena  arising  from  that  condition ; 

*  Housing's  description   is  in  Haller^s  Colleot    Dissert.  InaugunJis  Gottin- 
gen,  vol.  i.,  p.  177. 
t  Loe,  nt.,p.  81. 

iWochenblatt  der  GeseUschaft  der  Wiener  Aertze,  1862,  No.  17,  p.  130. 
Hernia  Betroperitonealis,  £in  Beitng  zxu  GescMchte  innerer  Hemier.  Png. 
F.  A.  Cndnn,  1857,  p.  110. 


Macamster — On  two  liyrma  ofPeriiypMic  Pouches.     217 

the  lower  ribs  were  bent  inwards ;  there  was  a  compressed  stomach,  a 
very  characteristic  sehnilrleher  whose  right  end  reached  nearly  to  tiie 
crest  of  the  ilium.  This  yicious  habit  forcing  the  viscera  downwards 
eyidently  exaggerated,  if  it  did  not  canse,  the  disposition  of  the  'colon 
to  buiTow  behind  the  psoas  muscle,  and  thus  to  produce  this  fossa.  It 
is  interesting  also  to  note  that  one  of  Biesiadecld's  cases  was  also  a  female, 
while  in  Leeper's  the  pouch  was  utterly  unconnected  with  any  csBcal 
relation. 

The  other  instance  was  of  less  interest,  though  more  complex. 
In  an  old,  thin  female,  which  happened  to  be  on  the  next  table  in  the 
dissecting-room  to  the  case  just  cited,  the  caecum  had  just  reached  the 
iliac  fossa,  and,  consequently,  was  well  covered  with  peritoneum,  and 
its  fundus  had  just  begun  to  turn  forward  when  its  growth  was  arrested; 
hence  the  vermiform  appendix  hung  inwards  and' a  little  forwards 
below,  but  not  in  front  of  the  opening  of  the  ilium.  A  strong  ligament 
of  Housing  passed  from  the  csBcum  to  the  abdominal  wall,  forming  the 
outer  boundary  of  a  sub-c8Bcal  sac,  in  which  the  fundus  of  the  csBcum 
lay,  and  which  its  sharp  falciform  border  rendered  very  deep  and  dis- 
tinct. The  mesenteriolum  had  not  yet  reached  its  usual  perfect 
distinctness,  but  the  appendix  lay  in  a  distinct  peritoneal  fold,  at 
the  bottom  of  the  sub-c8Bcal  fossa,  whose  cavity  it  divided  into  an  inner 
and  outer  part,  the  former  having  a  shallow  digital  recess  from  its 
floor  under  the  ilium,  and  its  separation  from  the  outer  was  completed 
by  a  ridge  passing  from  the  mesenteriolum  to  the  anterior  and  ii^erior 
part  of  the  abdominal  wall,  as  represented  in  the  figure.  The  interest 
of  this  case  is,  that  it  shows  a  primary  stage  of  both  the  sub-csecal  and 
inferior  ilio-caecal  fossa,  in  which  the  two  are  confluent,  for  the  sac  in 
this  instance  is  really  a  sub-caecal  one  vrith  an  imperfect  septum.  A 
farther  descent  of  the  csBCum  would  have  been  attended  with  an  in- 
creasing prominence  of  the  vermiform  appendix,  and  an  increasing 
distinctness  of  the  mesenteriolum,  then  the  inner  fossa  would 
form  a  perfect  ilio-csBcal  recess,  while  the  outer  would  be  a  sub^ciecal 
fossa.  The  continued  descent  of  the  csecum,  however,  would  have  the 
effect  of  obliterating  the  sub-csscal  fossa,  and  leaving  then  the  ilio- 
cscal  alone.  The  resemblance  between  this  case  and  that  of  Waldeyer 
is  so  close  as  to  lead  me  to  believe  that  they  are  both  varieties  of  one 
^ecies;  and  the  comparison  of  these  with  the  other  cases  throws  a  dear 
^ght  on  the  genesis  of  these  peculiar  and  often  dangerous  pouches.* 

*  Since  this  paper  vaa  written  (June,  1875)  an  instance  has  come  under  my 
notice  of  a  very  peculiar  additional  variety  of  sub-caBcal  fossa.  In  a  male  adult, 
Aged  about  sixty,  a  narrow  slit-like  opening  was  found  below  and  in  front  of  the 
cecum,  about  U"  long,  and  starting  below  the  ilium,  and  extending  transrersely ; 
on  intioducing  tne  finger  it  passed  under  and  behind  the  csBcum,  and  the  fundus  of 
the  pouch  was  found  placed  upwards,  backwards,  and  outwards,  on  the  level  of  the 
ctest  of  the  ilium.  The  cecum  thus  lav  in  and  bounded  thia  fossa,  in  the  floor  of 
which  was  the  vermiform  appendix.  The  formation  of  such  a  pit  was  probably 
doe  to  the  occurrence  of  an  adhesion  between  the  layers  of  the  pNsritoneum  and  the 
back  of  the  cscum,  while  the  latter  was  descending ;  so  that  the  intestines,  in  pass- 
ing down,  instead  of  separating  thei  kminas,  as  tiiual,  left  thii  portion  behind  it. 
B,  X.  A.  PB00.I  ssB.  n.)  rott.  Utt  tcxnroi.  2  Q 


218  Proeeedingi  qf  the  Boyal  Irish  Academy. 


XXXIY. — "Note  ok  tee  Sfscxritm,  Tolaxoatiov,  avd  Fobic  or  tbm 
Zodiacal  Light;  as  obsertsd  nr  ths  Yeabs  1874  Ain>  1875.  By 
C.  E.  Bustok,  B.  ^.,  Member  of  the  Bodbiguez  Tbaitste  of 
Ybnus  Expedition  (Bbitish.)     (With  Plate  25.) 

[Bead  June  U,  1875.] 

Iir  the  year  1872,  the  Boyal  Irish  Academy  entrusted  me  with  a 
pecuniary  grant  which  was  to  be  applied  in  defraying  the  cost  of  con- 
struction of  a  spectroscope,  which  should  be  specially  adapted  to  the 
examination  of  the  extremely  faint  spectra  of  the  Aurora  and  Zodiacal 
Light.     ( Vide  Report  on  a  Spectroscope  of  the  binocular  form.*) 

An  opportunity  of  studying  the  phenomena  presented  by  the  Zodia- 
cal Light,  under  more  favourable  circumstances  than  those  which 
prevail  in  comparatively  high  latitudes,  was  afforded  to  me  by  my 
being  attached  to  the  observing  party  sent  by  the  British  Gk)veniment 
to  the  Island  of  Eodriguez,  situate  in  the  South  Indian  Ocean. 

This  fact  having  been  represented  to  the  Boyal  Irish  Academy,  and 
their  permission  having  been  obtained  to  the  employment  of  their  in- 
strument during  my  service  with  the  Transit  of  Yenus  Expedition 
alluded  to  above,  I  was  enabled  to  take  advantage  of  several  vivid  dis- 
plays of  the  Zodiacal  Light  which  occurred  while  I  was  absent  from 
the  United  Kingdom,  and  to  obtain  the  results  detailed  in  the  subse- 
quent sections  of  this  note. 

The  observations  will  be  entered  in  the  following  order : 

(1.)  Those  indicating  the  projected  fonn  of  the  luminosity : 

(2.)  Spectroscopic  results : 

(3.)  The  indications  of  sensible  polarization :  under  each  date  on 
which  observations  of  the  Light  have  been  made  in  more  than  one  of 
the  above  mentioned  respects. 

Date  and  Place  of  Observation, — 1874,  June  10*,  9^  80",  approximate 
local  mean  time.     Lat.  32°  N.,  Long.,  14"  W. 

Form, — The  Zodiacal  Light  mamfested  itself  very  distinctly  as  an 
iU-dcfined  luminosity  of  an  approximately  triangular  form,  six  or  seven 
degrees  in  breadth  at  the  horizon,  about  forty  degrees  in  lengtib, 
and  inclined  some  fifteen  degrees  to  a  vertical  circle  bisecting  its 
base. 

Spectrum, — ^The  spectroscope,  on  being  directed  to  the  bright  cen- 
tral region  of  the  luminosity,  showed  a  broad  and  nearly  continuous 
spectrum,  sharply  terminated  on  the  less  refrangible  side,  and  fad- 
ing gradually  into  complete  darkness  as  its  refningibility  increased. 
The  limits  of  the  spectrum  seen  are  defined  by  the  wave  lengths 

*  jiniea,  p.  42« 


BiTHTOK— JBTofo  on  the  Zodiacal  Light.  219 

6680  and  4610±  expressed  in  serenth-metres ;  the  nnits  employed  by 
Professor  Angstrom  in  preparing  his  maps  of  the  Bolar  Spectrum,  and 
adopted  in  this  notice.  Repeated  impressions  of  the  existence  of  a 
narrow  bright  band,  situated  at,  or  very  near  to,  the  less  refrangible 
end  of  the  continuous  spectrum  were  receiyed  this  eyening,  and  the 
wave  length  of  the  bright  band  determined  to  be  5680.  Strong  suspi- 
cions were  entertained  that  there  was  a  darkish  band  to  which  tiie 
wave  length  5360  t  10  was  assigned,  by  the  measures  taken.  These 
suspicions  were  strengthened  by  the  eridence  of  another  and  indepen- 
dent observer. 

Date. — June  11^  9^  30",  local  mean  time. 

Plaee  of  Ohservatimi. — ^Twenty  miles  N.E.  from  Grand  Canary. 

Spectrum, — ^As  on  the  preceding  night,  the  central  region  of  the 
Zodiacal  Light  yielded  an  almost  contmuous  spectrum,  the  sensible 
limits  of  which  had  the  waye  lengths  5670  and  4640  seyenth-metres, 
according  to  the  measures  obtained  on  this  occasion,  the  first  quoted 
being  probably  the  more  trustworthy,  on  account  of  the  much  more 
definite  termination  of  the  spectrum  at  its  less  than  at  its  more  refran- 
gible end.  No  mention  is  made  of  the  bright  line  seen  last  night,  in 
tiie  notes  made  on  the  present  occasion,  but  a  suspicion  is  recorded 
tiiat  another  very  narrow  and  extremely  faint  existed,  the  refrangibi- 
lity  of  which  was  less  than  that  of  the  more  defined  limit  of  the  con- 
tinuous spectrum.  (As  June  11  was  the  only  occasion  on  which  the 
second  bright  line  was  eyen  suspected,  it  is  not  included  in  .the  accom- 
panying representation  of  the  Zodiacal  light  Spectrum,  the  details  of 
which  are  laid  down  from  the  mean  of  tiie  measures  obtained,  con- 
yerted  into  waye  lengths  by  curyes  of  interpolation^     (Diagram  1.) 

The  continuous  spectrum  was  almost  interruptea  by  a  well-marked 
darkish  streak,  to  which  was  assigned  the  wave  length  5379. 

Polarization. — A  Savart  arrangement  yielded  traces  of  polarization 
in  planes  sensibly  parallel  to  the  principal  axis  of  the  Light.  These 
traces  of  polarization  could  hardly  be  due  to  lingering  twilight,  the 
depression  of  the  sun  below  the  horizon  being  not  far  from  35^  at  the 
time  of  observation.     (Diagram  1.) 

Dafo.— June  12*,  9*,  to  12*,  lOS  local  mean  time. 

Place  of  Observation.— Lai.  24J°  N.    Long.  16^  W. 

Spectrum. — ^The  Zodiacal  Light  appeared  much  brighter  than  on 
June  1 1*,  and  the  lowest  power  of  the  spectroscope  was  employed. 
The  spectrum  was  sharply  terminated  on  the  less  refrangible  side,  and 
I  was  convinced  that  there  was  in  this  position  a  well-defined  band, 
brighter  than  any  other  part  of  the  spectrum,  the  breadth  of  which 
was  estimated  to  be  approximately  equal  to  that  of  Frannhofer's  group 
(b),  as  seen  with  the  same  instrument.  The  wave  length  of  the  bright 
band  was  determined  to  be  5680.  The  dark  streak  seen  last  night  was 
again  detected,  and  its  position  recorded  by  two  observers  indepen- 


220  Proceedings  of  the  Boyal  Irish  Academy, 

dently,  whose  accordant  znearareB  indicate  its  ware  length  to  be  ap- 
proximately 6355.  The  more  refrangible  end  of  the  spectrum  was 
extremely  ill-defined,  and  the  measures  give  it  a  wave  length  which 
is  probably  much  too  great,  being  that  of  the  point  where  the  index 
in  the  field  of  the  eye-piece  ceased  to  be  visible,  namely,  4640  seventh- 
metres. 

2>tf^.— June  IS**,  9i»». 

Flaee  of  Ohservatum.—L&t  13'^  N.    Long.  17^°  W. 

Spectrum, — Ab  on  June  12'*,  with  the  exception  of  the  dark  band 
at  6366,  which  was  not  visible,  with  all  attention.  The  other  details 
of  the  spectrum  were  visible  vrith  the  usual  distinctness,  but  the 
measures  of  the  bright  line  were  unsatisfactory,  indicating  its  wave 
length  to  be  6720,  instead  of  6670,  or  6680,  as  previously  determined. 
This  untoward  discordance  may  have  been  caused  by  an  accidental 
shift  of  the  recording  levers„  due  either  to  insufftcient  tightening  of  the 
clamp  which  connects  them  with  the  telescopes,  or,  as  is  more  pro- 
bable, judging  from  the  tested  stability  of  the  zero,  to  my  having 
mistaken  the  acute  angle  formed  by  the  less  refrangible  edge  of 
the  bright  line  with  the  visible  edge  of  the  triangular  pointer  for 
the  proper  point  of  reference,  namely,  the  apex  of  the  triangle. 

On  directing  the  instrument  to  any  part  of  the  sky,  except  that 
occupied  by  the  Milky  Way,  the  same  spectrum,  much  diminished  in 
intensity ,  but  otherwise  recognisable,  was  seen  as  when  viewing  the 
central  regions  of  the  Zodiactd  Light.  The  same  fact  was  observed  on 
many  subsequent  occasions  in  vddely  different  localities,  and  vnth 
another  instrument.  It  is,  perhaps,  scarcely  possible  to  attribute  this 
spectrum  to  any  diffused  reflection  of  the  solar  rays,  for,  at  the  hour 
of  observation,  the  sun's  depressioii  below  the  horizon  was  nearly  40° 
and,  furthermore,  the  luminous  appearance  which  yielded  the  spectrum 
its  greatest  brilliancy  retained  its  form  and  position  among  the  stars 
sensibly  unchanged  during  the  evening. 

The  facts  mentioned  in  the  last  words  of  the  preceding  sentence, 
taken  together  with  the  apparently  unique  character  of  the  spectrum^ 
appear  to  preclude  the  supposition  that  it  was  due  to  any  terrestrial 
aurora,  the  spectrum  of  which  differs  much  from  the  Zodiacal  Light 
spectrum,  as  regards  both  its  aspect  and  the  positions  of  the  lines 
hitherto  recorded,  so  far  as  they  are  known  to  me. 

A  suggestion  made  many  years  ago,  I  believe,  by  Sir  John  Hers- 
chel,  to  the  effect  that  the  observed  extension  of  the  Zodiacal  Light 
from  the  sun  indicated  that  the  earth  is  probably  immersed  in  the 
outer  portions  of  a  luminous  haze  of  lenticular  form,  symmetrically 
disposed  about  the  sun  and  having  its  principal  section  nearly  co- 
incident with  the  plane  of  the  EcHptic,  seems  to  afford  a  possible 
explanation  of  the  diffusion  of  the  light  over  the  whole  sky,  indicated 
by  the  spectroscope,  and  also  of  certain  anomalies  in  the  form  of  the 
denser  portion,  hereafter  to  be  recorded, 


BuBTON — Note  on  the  Zodiacal  Light.  221 

X)ate. — 1874,  Angost  3^  8*>  local  mean  tune. 

Flaee  of  Oh8ervatum.—EM.Q.  <<  Shearwater."  Lat.  28''  4'S. ;  Long. 
58°46'E. 

Spectrum, — The  bright  line  forming  the  less  refrangible  boundary 
of  the  yisible  spectrum  was  well  observed,  being  much  more  distinot 
than  on  former  occasions.  This  line  would  be  more  accurately  de- 
scribed as  a  narrow  bright  band,  with  tolerably  well-defined  edges ; 
especially  that  which  is  least  refrangible.  Its  centre  has  a  wave 
length  of  5670  seventh-metres,  accoiding  to  the  measures  obtained. 
The  dark  streak  at  5355 1  was  not  seen,  there  being  barely  time  for 
the  measures  of  the  bright  band,  as  clouds  rapidly  formed  and  ob- 
scured the  Zodiacal  light.  The  existence  of  the  bright  band  was 
verified  by  one  of  the  i^p's  officers,  Lieut.  Pullen,  E.N.,  who  kindly 
gave  me  most  efficient  assistance  on  the  occasion. 

Date. — 1874,  August  5<<  6**  50«  local  mean  time. 

Place  'of  Ob8erv<Uum.—KM.Q.  "  Shearwater."  Lat.  23^  45'  S. ; 
Long.  68°  36'  E. 

Spectrum. — ^The  narrow  bright  streak  was  again  seen,  and  its  place 
determined,  but  the  instrument  seems  to  have  been  deranged  between 
the  observation  of  the  Zodiacal  Light  and  of  the  standwi  spectrum 
— ^in  this  case  the  solar  spectrum.  The  measure  has  been  rejected. 
There  was  a  verj^  faint  and  ill-terminated  extension  of  light  on  the 
less  refrangible  side  of  the  bright  band,  which  may  have  been  due  to 
some  remains  of  twilight,  or  to  the  near  neighbourhood  of  the  planet 
Venus,  which  was  then  very  brilliant,  to  the  region  under  inspection. 
A  dark  streak,  apparently  somewhat  less  refnmgible  than  solar  E, 
was  distinctly  seen.  The  breadth  of  this  streak  was  estimated  as  equal 
to  about  40  units  of  Angstrom's  sciale. 

Date, — 1874,  August  10^  7^.  Sour  not  noted  at  the  time,  but 
inserted  here  from  recollection. 

Place  of  Observation. — ^Fort  Louis,  Mauritius. 

Spectrum. — ^The  bright  band  seen.  The  measures  give  5690  seventh- 
metres  as  its  wave  length. 

Dtf^.— 1874,  August  11*  8^ 

Place  of  Observation. — ^Fort  Louis,  Mauritius. 

Spectrum. — ^Measure  largely  in  error,  some  slip  of  the  damp  or 
record  carrier  having  probably  occurred. 

Polaritatum. — ^Lieut.  Neate,  the  chief  of  the  Eodriguez  Transit  of 
Venus  Expedition,  was  able  to  detect  bands  parallel  to  the  principal 
axis  of  the  luminosity,  while  making  use  of  die  Savart  arrangement 
before  mentioned.  I  could  not  see  them,  beiag  fatigued  with  the 
previous  spectroscopic  work. 

The  bands  seen  indicated,  according  to  Lieut.  Ifeate's  remarks,  a 
slight  degree  of  polarization  in  planes  parallel  to  the  axis  of  the  Light. 


222  Proeeedinga  of  the  Royal  Irish  Academy. 

Daie.—lS74,  Angost  12^.    Tiixie  not  noted.^ 

Place  of  Observation. — At  sea — ^between  Mauritins  and  Bodrigaez. 

Polarization. — With  the  Bavart  arrangement  bands  were  visibley 
which  were  sensibly  parallel  to  the  axis  of  the  Zodiacal  light,  when 
at  their  greatest  intensity;  and  the  plane  of  polarization  indicated 
seemed  to  lie  in  the  same  plane  as  the  bands. 

A  Nicol  prism  confirmed  the  resnlt  obtained  with  the  Savart — ^the 
mode  of  obseryation  being  this :  the  prism  was  rotated  slowly  nntil  a 
faint  star  involved  in  the  Zodiacal  light  appeared  brightest. 

Da^.— 1874,  October  10^  7H. 

Place  of  Observation. — Rodriguez.     Observatory  House. 

Spectrum. — The  measures  obtained  give  a  wave  length  of  5655 
seventh-metres  for  the  bright  line  terminating  the  spectrum  on  the 
less  refrangible  side. 

After  October  10,  the  use  of  the  recording  spectroscope  had  to  be 
discontinued,  to  my  great  regret ;  the  cement  used  for  securing  the 
prisms  having  been  affected  by  the  heat  and  dryness  of  the  climate,  and 
become  brittle  and  unsafe. 

The  only  substitute  available  (pure  wax)  proved  equally  unreliable. 

Date.—IB75,  Janiiary  2^  8>»  to  9»»  30«,  local  mean  time. 

Place  of  Observation. — Curepipe,  Mauritius.  1800  feet  above  sea 
level. 

Spectrum. — ^A  pocket  spectroscope  with  one  compound  prism  of 
direct  vision  showed  a  ZodLacal  Light  Spectrum  identical  with  that 
formerly  observed,  except  as  regards  the  dark  streak  of  wave  length 
5855,  which  was  not  detected. 

Polarization. — A  Nicol  prism,  rotated  about  its  longer  axis,  produced 
marked  variations  in  the  intensity  of  the  part  of  the  Zodiacal  Light 
viewed,  upon  which  I  kept  my  attention  nxed  during  the  experiment 
by  retaining  two  faint  stars  involved  in  the  luminous  haze  in  the  centre 
of  the  field.  These  stars  were  barely  visible  to  the  unarmed  eye,  but 
were  well  seen  when  the  principal  plane  of  the  prism  was  at  right 
angles  to  the  axis  of  the  Light. 

The  Savart  arrangement  also  indicated  polarized  Hght,  but  much  lest 
decisively,  as  the  Light  was  setting. 

^orm. — Herr  Heidom,  of  the  German  Expedition  to  Mauritius  to 
observe  the  Transit  of  Venus,  joined  me  in  making  careful  observations 
on  the  general  form  and  position  of  the  luminosity. 

We  noted  that  the  northern  boundary  of  the  Light  was  much  better 
defined,  and  more  nearly  straight,  than  the  southern ;  also  that  it  passed 
close  to  a  great  circle  described  through  rf  Tauri  and  {  Pegasi. 
The  southern  boundary  nearly  coincided  with  a  parabolic  curve  passing 
through  a  Tauri,  P  Ceti,  and  a  Gruis.  The  luminosity  extendi!  from 
the  W.  horizon,  where  its  breadth  was  about  twenty-five  degrees,  cer- 
tainly as  far  as  the  Milky  Way  in  Taurus,  its  apparent  width  at  the 


BuBTON — Note  an  the  Zodiacal  Light.  223 

point  of  intersection  being  nearly  three  degrees.  (Sketch  2.)  Within 
this  luminons  region  there  appeared  to  be  a  distinct  nucleus,  the 
intensity  of  the  Light  increasing  somewhat  abruptly  toward  the 
centre  from  both  sides,  and  forming  a  tolerably  defined  central 
cone,  five  or  six  degrees  broad  at  the  horizon,  and  twenty-five 
degrees  in  length.  At  an  elevation  of  ten  degrees  from  the  horizon 
the  central  region  of  the  light  appeared  to  exceed  in  intrinsic  bright- 
ness every  part  of  the  Milky  Way,  excq>t,  perhaps,  the  narrow  stream 
in  Argo. 

Date, — 1875,  February  5**  7^  local  mean  time. 

Place  of  Observation.— Lai.  3°  8.     Long.  70°  E. 

Form  of  Light. — Lieutenant  Neate,  Chief  of  the  Bodriguez  Transit 
of  Venus  Expedition,  observed  a  short  branch  or  spur  diverging  at  a 
small  angle  horn  the  base  of  the  principal  mass  of  Light  on  the  south 
side,  as  shown  in  Sketch  3.  The  spur  was  very  faint  when  compared 
with  the  neighbouring  luminosity,  but  was  distinctly  seen  by  another 
observer  when  Lieut^ant  Neate  drew  his  attention  to  it. 

DaU. — 1875,  February,  7*  7^  ±  local  mean  time. 

Place  of  Observation.— L&t  2°  30'  N.     Long.  73°  E. 

Spectrum. — The  pocket  spectroscope  used  on  1875,  January  2**, 
showed  a  faint  line,  estimated  to  be  near  solar  E.  It  was  separated,  or 
nearly  separated,  from  a  short  continuous  spectrum  by  a  narrow  dark 
band.  The  continuous  spectrum  faded  gradually  into  darkness,  with 
increasing  refrangibiHty.  This  compound  spectrum  varied  in  brightness^ 
but  did  not  change  its  character  when  the  instrument  was  swept  round 
in  a  small  circle  parallel  to  the  horizon  at  an  elevation  of  15°  or  20°, 
except  when  it  received  light  from  any  part  of  the  Milky  Way,  which 
added  its  spectrum  to  the  other,  and  produced  confusion. 

The  brightness  of  the  Zodiacal  Light  Spectrum  was  far  greater  when 
the  instrument  was  directed  toward  the  bright  central  region  of  the 
luminous  cone-shaped  haze  than  when  it  received  light  from  any  other 
part  of  the  sky.    (Sketch  4.) 

Polarization. — With  the  Savait  polariscope  bands  were  distinctly 
seen,  especially  when  the  principal  plane  of  the  Nicol  prism  was  nearly 
at  right  angles  to  the  axis  of  the  Zodiacal  Light,  and  the  disposition  of 
the  bands  indicated  that  the  plane  of  polarization  was  inclined  about 
75*  to  that  line. 

This  result  was  confirmed  by  the  subsequent  observation  with  the 
simple  Kicol  prism,  made  independently  by  the  same  observers  (Messrs. 
Keate  and  Burton). 

Date.~l  875,  February  11. 

Place  of  Observation. — At  sea,  near  Trincomalee,  Ceylon. 

Brightness. -^ThQ  Zodiacal  Light  began  to  be  visible  less  than  half 
an  hour  after  sunset^  and  despite  the  neighbourhood  of  the  crescent 
moon« 


224  Proceedings  of  the  Royal  Irish  Academy. 

Date.—ms,  March  81*  8^ 

Place  of  Ohservaiion.    Off  Cape  St.  Yincent. 

Form, — ^The  Zodiacal  Light  was  well  seen.  The  upper  part  ap- 
peared to  intersect  a  line  passing  through  a  and  fi  Geminomniy  ahout  8° 
or  10^  sonth  of  the  latter  star.  On  this  occasion  the  southem  honndary 
of  the  luminous  haze  was  much  more  definite  than  the  northern. 
There  was  an  eyident  nucleus  or  brighter  region  included  by  the 
outer  haze.  This  nucleus  was  about  25^  in  length,  and  almost  in- 
Tolyed  the  Pleiades  on  its  northern  side.     (See  Diagram  5.) 


parti; 


SUIOCAET. 

The  observations  detailed  in  this  memoir  appear  to  indicate : — 
1.)  That  the  Zodiacal  Light  is  emitted  by  matter  partly  liquid  and 


ly  solid,  intermixed  with  gas. 

(2.)  That  it  reaches,  and  probably  surrounds  the  earth,  as  shown 
by  the  visibility  of  the  spectrum  when  viewing  any  part  of  the  sky  un- 
occupied by  the  Milky  Way,  and  by  the  change  of  form  seen  when  the 
observer  passed  from  S.  to  N.  latitudes.     (Shown  in  the  Diagrams.) 

It  only  remains  for  me  now  to  express  my  deep  sense  of  the  honour 
which  the  Academy  have  conferred  upon  me  by  committing  their  instru- 
ment to  me  for  this  work ;  as  well  as  my  regret'  that  other  avocations, 
while  abroad  and  in  charge  of  a  very  different  species  of  research, 
together  with  innumerable  circumstances  connected  with  the  instru- 
ment, the  weather,  the  presence  of  the  moon  and  even  of  Yenus  before 
inferior  conjunctions,  have  rendered  this  Beport  much  less  complete 
than  it  would  otherwise  have  been. 


Davy — On  Arsenicul  Compounds,  225 


XXXV. — Ojt  a  Ready  Means  op  Detecttno  Ambwical  CoMPOtnrDs. 
By  Edmund  W.  Davt,  A.  M.,  M.  D.,  Professor  of  Forensic  Medi- 
cine, Eoyal  College  of  Surgeons,  etc. 

[Bead  June  U,  1875.] 

The  extensive  employment  of  certain  compounds  of  the  metal  arsenic 
for  the  criminal  destruction  of  human  life,  has  rendered  their  detection 
under  different  circumstances  a  matter  of  great  importance  to  society ; 
and  to  attain  this  end  they  have  long  been  objects  of  much  interest  to 
the  chemist  and  toxicologist.  Fortunately  for  mankind,  the  metal 
itself,  as  well  as  its  combinations,  have  been  found  to  be  endowed  with 
very  characteristic  chemical  properties,  and  on  these  are  based  several 
excellent  tests,  by  which,  in  the  hands  of  the  chemist  or  in  those 
skilled  in  the  detection  of  poisons,  very  minute  quantities  of  arsenic  or 
of  its  compounds  can  be  identified  with  more  or  less  facility ;  and  the 
fear  of  such  detection  has  acted  as  a  great  preventative  against  their 
criminal  employment  as  poisons ;  for,  before  such  means  of  recognising 
their  presence  were  discovered,  secret  poisoning  by  arsenious  acid, 
which  is  popularly  known  as  **  arsenic,"  was  carried  on  to  a  feaiful 
extent,  a  greater  number,  perhaps,  of  indivduals  having  been  already 
deprived  of  life  by  that  substance  than  by  aU  the  other  known  poisons 
put  together.  But  now,  owing  to  our  possessing  the  means  by  which 
even  very  minute  quantities  of  arsenical  compounds  can  be  detected 
with  almost  unerring  certainty,  and  there  having  been  of  late  years 
certain  legal  restrictions  placed  on  the  sale  of  arsenic,  cases  of  homi- 
cidal poisoning  by  that  substance  have  now  become  comparatively  rare. 
Still,  as  such  cases  or  those  from  accident  do  from  time  to  time  occur, 
and  as  dilPerent  arsenical  compounds  are  used  for  a  number  of  industrial 
purposes,  some  of  which  are  highly  objectionable,  endangering  as  they 
do  the  health,  and  even  lives,  of  many  individuals,  it  is  very  desirable 
that  we  should  be  able  readily  to  detect  those  virulent  substances,  not 
only  where  they  may  occur  by  design  or  accident  in  different  articles 
of  food  or  drink,  or  in  the  bodies  of  those  who  have  died  from  their 
effects,  but  likewise  where  they  may  exist  in  various  manufactured 
products,  the  use  of  which  might  be  attended  with  very  serious  conse- 
quences. The  test  which  I  would  now  propose  being  one  of  such 
simplicity  and  ease  of  execution  that  it  might  be  performed  by  almost 
any  one,  will,  I  should  hope,  be  found  useful  for  the  objects  stated, 
especially  to  those  who  are  not  very  conversant  with  the  details  of 
chemical  manipulation.  As  it  is  a  modification  of  Mr.  Marsh's  test,  it 
is  necessary  for  me  briefly  to  refer  to  that  method  before  describing  the 
one  I  would  now  suggest.  That  gentleman's  test,  as  is  well  known, 
is  founded  upon  the  circumstance,  that  nascent  hydrogen  in  presence 
of  certain  compounds  of  arsenic  will  give  rise  to  the  formation  of 
arseniuretted  hydrogen ;  a  gas  which,  being  possessed  of  very  charac- 

K.  I.  A.  P&OO.,  BBB.  II.,  VOL.  U.,  8CIEMC1.  2  H 


226  Proceedings  of  the  Royal  Irish  Academy. 

teristic  propertioB,  may  be  easily  recognised,  and  thas  very  minnte 
quantities  of  arsenic  under  different  circumstances  can  be  readily 
detected.  This  method,  as  proposed  by  its  discoverer,  consists  in  gene- 
rating, in  a  suitable  apparatus,  hydrogen  by  the  action  of  dilute 
sulphuric  acid  on  metallic  zinc,  and  then  adding  in  the  state  of  solution 
the  arsenical  compound,  when  arseniuretted  hydrogen  will  be  quickly 
generated,  and  a  fine  jet  of  the  gas  being  ignited,  and  a  cold  surface 
placed  down  on  the  top  of  the  flame,  very  characteristic  spots  or  stains 
of  metallic  arsenic  will  bo  produced ;  or  the  gas  being  passed  through  a 
heated  tube,  it  will  be  decomposed,  and  a  metallic  sublimate  formed  at 
a  short  distance  beyond  the  heated  portion.  I  need  not  refer  to  the 
apparatus  recommended  by  Mr.  Marsh  for  carrying  out  his  test,  as  it  is 
now  so  well  known,  nor  to  the  modifications  of  it  which  have  been 
subsequently  proposed ;  and  I  must  acknowledge  that  this  beautiful 
means  of  detecting  arsenic,  owing  to  its  great  delicacy  and  very  conclu- 
sive results  in  the  hands  of  the  experienced  chemist,  leaves  but  little 
to  be  desired.  It,  however,  labours  under  this  serious  disadvantage, 
that  the  acid  and  the  zinc  which  are  employed  in  the  process  may  one 
or  other  of  them,  or  even  both,  contain  more  or  less  of  arsenic  as  an 
impurity,  and  consequently  the  indications  of  that  substance  which  are 
thus  obtained,  may  bo  due  not  to  its  existing  in  the  suspected  matter 
or  object  under  investigation,  but  to  its  occurring  as  an  impurity  in  the 
materials  employed  in  this  process  for  its  detection;  and  I  may  add  that 
it  is  difficult  to  get  in  commerce  the  zinc  and  sulphurio  acid  required 
perfectly  free  from  arsenic. 

To  obviate  more  or  less  this  source  of  foUacy^  several  modifications 
of  the  original  process  of  Marsh  have  been  suggested.  Thus,  Fleitmann, 
some  years  ago,  proposed  the  use  of  a  strong  solution  of  caustic  potash, 
assisted  by  heat,  instead  of  the  acid,  to  act  on  the  zinc  as  a  means  of 
generating  the  hydrogen  gas,  and  in  this  way  one  source  of  arsenical 
contamination  was  avoided.  It  was  found,  however,  to  be  too  slow  a 
means  of  generating  hydrogen  to  detect  arsenic  in  the  usual  way  by 
Marsh's  method.  Professor  Bloxam  has  suggested  the  employment  of  a 
galvanic  battery  for  the  generation  of  the  same  gas,  and  in  this  way 
obviates  the  use  of  zinc,  and  thus  excludes  another  possible  source  of  fal- 
lacy ;  but,  owing  to  the  trouble  and  expense  attendant  on  the  use  of  a  gal- 
vanic battery,  which  for  this  purpose  must  be  of  some  power,  and  the 
arrangement  being  of  rather  a  complicated  character,  and  still  requiring 
sulphuric  acid,  it  has,  I  believe,  been  but  little  employed.  I  should 
also  add  that  the  metal  aluminium,  and  more  recently  magnesium,  have 
been  proposed  as  substitutes  for  zinc  in  Marsh's  process  or  in  Fleitmann's 
modification  of  it,  as  being  less  likely  to  be  contaminated  with  arsenic 
than  that  metal.  The  modification  which  I  would  now  suggest,  and 
which,  as  far  as  I  can  ascertain,  has  not  hitherto  been  proposed,  is  the 
employment  of  an  amalgam  of  sodium  and  mercury  as  a  means  of  gene- 
rating the  hydrogen  required  for  the  test :  and  by  the  use  of  this 
substance  I  do  away  with,  altogether,  the  necessity  of  any  acid,  and  I 
employ  two  metals  which  are  not  liable  to  arsenical  contamination.   As 


Davy — On  Arsenical  C(nnpounds.  227 

to  sodium,  I  am  not  aware  that  arsenic  has  ever  been  pointed  out  as  one 
of  its  impurities ;  and,  as  to  its  presence  in  mercury,  that  is,  I  believe, 
a  circumstance  of  very  rare  occurrence ;  but,  should  it  exist  in  that  metal 
as  an  impurity,  it  can  be  readily  removed  from  it  by  digesting  tho 
mercury  in  ddluted  nitric  acid,  and  afterwards  well  washing  it  with 
water.  The  amalgam  which  I  have  found  to  answer  very  well  for  the 
detection  of  arsenic,  consists  of  one  part  by  weight  of  sodium  to  eight  or 
ten -parts  of  mercury,  and  is  easily  made  by  heating  moderately  in  a  test 
tube  over  a  lamp  the  mercury,  and  then  adding  gradually  in  small 
pieces  the  sodium,  taking  care  to  keep  away  the  face,  if  unprotected 
from  the  mouth  of  the  tube,  lest  some  of  that  metal  in  an  ignited  state 
might  be  spirted  out  during  the  addition  of  the  first  portions.  Those 
metals  readily  combine  under  these  circumstances,  forming  an  alloy 
that  is  liquid  whilst  hot,  but  becomes  hard  and  brittle  when  cold. 
The  contents  of  the  tube,  while  still  hot  and  liquid,  are  quickly 
poured  out  on  a  clean  plate,  and,  when  cool,  broken  up  in  small 
lumps,  which  are  then  inmiediately  placed  in  a  well  corked  or  stoppered 
bottle. 

The  way  I  employ  this  amalgam  is  simply  to  place  the  suspected 
solution,  or  solid  matter  along  with  a  Uttle  water,  in  the  bottom  of  a 
test  glass,  then  add  a  small  bit  of  the  amalgam,  about  the  size  of  a 
grain  of  wheat,  and  lastly,  place  without  delay,  on  the  top  of  the 
glass,  a  piece  of  white  filtering  paper  or  the  cover  of  a  white  porce- 
lain crucible  moistened  with  a  drop  of  a  dilute  solution  of  nitrate  of 
silver,  slightly  acidulated  with  nitric  acid,  when  if  arsenic  is  present,  a 
duU  black  or  deep  brown  stain  on  the  paper,  or  a  dark  silvery  one  on  the 
porcelain,  will  be  quickly  developed  in  the  part  moistened,  owing  to 
the  silver  of  the  salt  being  reduced  to  the  metallic  condition  by  the 
agency  of  the  arseniuretted  hydrogen  thus  evolved,  which,  coming  in 
contact  with  the  nitrate  of  silver,  gives  rise  to  the  following  reaction : 
H^s  -^  6  AgNO,  +  3H,0  =  6  HKO3  +  HjAsO,  +  8  Ag,. 

The  silver  solution,  which  I  have  found  to  answer  very  well  for 
this  purpose,  was  made  by  dissolving  twenty  grains  of  the  nitrate  in 
an  ounce  of  distilled  water^  and  then  adding  two  drops  of  strong  nitrio 
acid,  to  render  the  solution  slightly  acid.  I  may  further  add  that  I 
generally  place  a  small  disc  of  bibulous  paper  between  the  mixture  in 
the  glass  and  the  paper  or  cover  moistened  with  the  silver  solution,  to 
intercept  any  particles  of  the  liquid  which  might  otherwise  be  projected 
against  them,  producing  there  minute  black  spots,  and  thus  inteif  enng 
with  the  results  of  this  test. 

I  have  found  that  exceedingly  minute  quantities  of  arsenic  can  be 
readily  detected  by  this  very  simple  process ;  thus  the  one  thousandth 
part  of  a  grain  of  arsenious  acid,  dissolved  in  one  cubic  centimetre  of 
distilled  water,  gives  a  very  decided  effect  in  a  few  moments ;  but  much 
smaller  quantities  are  detectable  by  it ;  thus  the  one  hundred  thou- 
sandth or  even  the  one  millionth  part  of  a  grain  of  arsenious  acid,  dis- 
solved in  the  same  quantity  of  water  (one  cubic  centimetre),  will 
afford,  by  the  blackening  of  the  silver  salt,  after  a  little  time,  an  indi- 


228  Proceedings  of  the  Royal  Irish  Academy. 

cation  of  tlie  presence  of  arsenic.  I  have  also  ascertained  that  this 
method  of  detecting  arsenic  is  not  alone  directly  applicable  to  where 
it  exists  as  arsenious  acid,  but  likewise  to  several  other  compounds  of 
arsenic,  whether  they  are  soluble  or  insoluble  in  water — ^thus,  for  ex- 
ample, the  two  sulpludes  of  arsenic  (orpiment  and  realgar),  the  alkaline 
arseniates,  and  even  metallic  arsenic  itself  if  reduced  to  powder,  will 
readily  show  their  arsenical  nature  by  this  test ;  and  we  may  in  a  few 
moments  detect  'by  it  the  occurrence  of  arsenic  in  different  green, 
yellow,  and  orange  pigments,  which  are  still  much  employed  in  the 
manufacture  of  wall  papers,  in  painting,  and  in  the  colouring  of  cer- 
tain textile,  and  other  articles  used  in  dress  or  for  ornamentation. 
Thus,  for  example,  if  a  little  of  the  colouring  matter  of  any  arsenical 
pigment  be  scraped  off  from  a  wall  paper,  or  a  small  piece  of  the  paper 
itself  be  taken  and  placed  in  a  test-glass  with  a  Uttle  water,  and  hay- 
ing being  stirred  or  shaken  to  detach  the  colour,  a  piece  of  the  amalgam 
be  added,  it  will,  by  the  blackening  of  the  olver  salt  employed  as 
before  described,  soon  indicate  the  presence  of  arsenic.  In  the  same 
way  it  can  be  easily  demonstrated  that  the  colouring  matter  in  certain 
green  tarletans,  calicoes,  and  other  articles  used  for  dress  or  for  orna- 
ment, are  arsenical.  I  may  further  state  that  the  presence  of  organic 
matter  seems  to  interfere  but  little  with  this  test,  for  I  have  found 
that  very  minute  quantities  of  arsenious  acid,  when  mixed  with  con- 
siderable amounts  of  milk,  tea,  coffee,  ale,  porter,  soup,  or  stirabout, 
could,  with  almost  the  same  facility,  be  detected  by  this  method,  as 
where  they  were  only  simply  dissolved  in  water ;  thus  showing  that 
the  cases  to  which  it  is  applicable  are  very  extended. 

But  I  should  here  observe  that,  as  in  the  case  of  Marsh's  original 
method,  there  is  one  other  metal  which,  under  certain  circumstances, 
wiU  produce  with  the  sodium  amalgam  results  closely  resembling 
those  occasioned  by  arsenic ;  the  metal  I  refer  to  is  antimony,  which  is 
capable  of  uniting  with  nascent  hydrogen  to  form  a  gas  (antimoniuretted 
hydrogen),  which,  coming  in  contact  with  nitrate  of  silver,  produces  a 
black  antimonide  of  that  metal,  by  the  following  reaction :  Hj  Sb  -h  3 
Ag  NOj  =  Ag,  Sb  +  3  H^NTOs,  and  the  blackening  of  the  silver  salt 
from  the  formation  of  that  compound  might  be  easily  mistaken  for  the 
effect  produced  by  the  arsenical  gas. 

But  owing  to  the  fact,  first  pointed  out  by  Fleitmann,  that  antimoniu- 
retted hydrogen  is  not  evolved  (except,  perhaps,  as  a  mere  trace),  from 
strongly  alkaline  solutions,  though  the  conditions  may  exist  there  for  its 
formation,  and  as  the  action  of  the  sodium  amalgam  is  to  render  the  mixture 
quickly  alkaline,  there  will  be  only  a  very  minute  quantity  of  the  an- 
timony that  may  be  present  so  evolved ;  and,  by  previously  rendering 
the  mixture  strongly  alkaline,  we  may  almost  altogether  prevent  the 
evolution  of  that  gas.  If,  however,  we  make  the  mixture  containing 
the  antimony  in  solution  first  strongly  acid,  and  then  add,  the  amalgam, 
or  even  acidify  after  its  addition,  the  antimoniuretted  hydrogen  will 
be  evolved  in  abundance,  producing  a  deep  black  stain  on  the  paper 
moisti'nrd  with  the  nitrate-  of  silver ;  and,  for  the  purpose  of  this  acidi- 


Davy — On  Arsenical  Compounds.  229 

fication,  I  have  found  tliat  tartario  acid  answers  very  well.  As  the 
presence  of  alkalies  in  8olati(Hi  do  not  inteif  ere  with  the  evolution  of 
the  arsenical  gas,  this  is  itself  a  means  of  distinguishing  the  two  metals, 
arsenic  and  antimony. 

But  it  may  he  occasionally  necessary  to  determine  whether  the 
effects  observed  on  the  paper  moistened  with  nitrate  of  silver  are  due 
to  arsenic  or  to  antimony.  There  are  different  methods  by  which  we  may 
determine  this  question ;  but  the  one  I  ha^e  found  IJbe  simplest  and 
on  the  whole,  the  most  satisfactory,  is  to  digest  the  paper  stam  in  sul- 
phide of  ammonium,  when  the  arsenic  or  antimony  present  will  be  coi\- 
verted  into  a  sulphide,  and  dissolved  by  the  excess  of  the  alkaline  salt, 
leaving  the  silver  sulphide  undissolved,  and  adhering  principally  to  the 
paper — the  alkaline  solution,  on  being  evaporated  to  dryness,  will,  in  the 
case  of  arsenic,  leave  a  bright  yellow  residue  almost  insoluble  in 
hydrochloric  acid,  whereas  in  the  case  of  antimony,  an  orange  one  will 
remain,  which  readily  dissolves  in  that  acid,  at  least  on  the  application 
of  heat. 

Before  concluding,  I  wish  to  observe,  that  according  to  some  ex- 
periments recently  made  by  Dr.  Russell,  it  appears  that  hydrogen  alone 
is  capable  of  reducing  solutions  of  nitrate  of  silver  to  the  metallic 
state ;  but  this  action,  even  from  his  observations,  is  an  exceedingly 
alow  one,  and  takes  place  to  a  very  minute  extent  in  dilute  solutions. 
On  the  other  hand,  M.  H.  Pellet  maintains,  that  hydrogen  carefully 
freed  from  acid  and  arsenic,  by  passing  it  through  solutions  of  soda  and 
of  nitrate  of  silver,  has  no  action  on  that  salt  at  the  ordinary  tempera- 
ture. But  he  states,  that  nitrate  of  silver  which  has  been  fused  possesses 
an  alkaline  reaction  in  solution,  and  that  a  slight  precipitate  is  produced 
in  such  by  pure  hydrogen ;  if,  however,  he  observes,  a  drop  or  two  of 
nitric  acid  be  added,  then  nothing  is  precipitated.  Be  this  as  it  may,  as 
regards  the  reducing  action  of  pure  hydrogen,  I  found  in  an  experiment 
I  made,  that  hydrogen  which  had  been  passed  through  solutions  of 
caustic  soda,  and  of  nitrate  of  silver,  and  was  afterwards  brought  in 
contact  with  a  porcelain  crucible  cover,  moistened  with  the  dilute  and 
acidulated  solution  of  nitrate  of  silver  already  noticed,  produced  only 
the  faintest  possible  effect,  even  after  several  hours'  exposure  to  a 
stream  of  this  gas,  and  this  very  slight  action  might  possibly  be  due  to 
the  hydrogen  not  being  perfectly  freed  from  its  impurities.  Conse- 
quently, it  is  very  doubtful  that  any  reduction  of  the  silver  salt  from 
the  hydrogen  alone  will  occur  under  the  circumstances  of  the  proposed 
test.  Finally,  I  must  observe,  that  where  paper  moistened  with  the 
silver  solution  is  used  to  detect  arsenic  or  antimony,  we  must  bear  in 
mind  that  nitrate  of  silver  will  alone,  after  some  time,  blacken  the 
paper,  especially  if  it  is  exposed  to  the  light;  but  this  gradual 
change  which  is  so  produced  is  very  unlike  the  rapid  effect  that  takes 
place  where  either  arseniuretted  or  antimoniuretted  hydrogen  acts  on 
paper  moistened  with  that  silver  salt. 


230  Proceedings  of  the  Royal  Irish  Academy. 


X^XYI. — FUBTHEB  ReSEABCHES    Oir  THE  DiSSOCIATIOir   OF  MOLECITLKS 

m  Solution.    By  Chables  R.  C.  Tichboene,  Ph.  D.,  F.  C.  S.,  &c. 

[Bead  June  14,  1876.] 

Iv  my  preTioufi  researches  in  connexion  with  the  dissociation  of  the  mole- 
cules, which  are  generally  known  as  salts,  I  have  shown  that  there  is 
probably  in  every  case  a  partial  separation  of  the  base,  determined  by 
the  thermal  force  acting  upon  these  molecules  when  in  solution.*  The 
&^t  basic  salt  produced  does  not  differ  much  from  the  original  molecule, 
but  its  basicity  goes  on  increasing  with  the  increment  of  heat,  ob- 
tained, we  will  say,  by  increased  pressure,  until  a  complete  temporary 
analysis  of  the  salt  is  effected,  even  if  the  result  of  the  action  is  not  a 
permanent  decomposition.  We  may  also  view  these  extreme  cases  as 
partaking  of  the  nature  of  g^ous  dissociation,  it  having  been  proved 
by  Dr.  Andrews  that  there  is  no  hard  line  of  demarcation  between  the 
liquid  and  gaseous  state  of  matter. 

I  have  also  determined  that  the  first  thermanalytic  action  of  heat 
upon  hydrated  salts,  although  still  in  the  presence  of  water,  is  to  gra- 
dually and  completely  dehydrate  the  s€Jtfl,  and  to  render  them  anhy- 
drous. The  water  of  hydration,  so  called,  being  merely  the  last  and 
crowning  portion  of  the  compound  molecule,  and  therefore  the  portion 
of  the  molecule  least  amenable  to  the  chemical  or  molecular  force,! 
it  is  not  necessary  to  dwell  upon  this  point  of  the  subject  any  further 
than  to  bear  in  mind  that  we  are  actually  operating  upon  the  anhy- 
drous salt.  Presuming,  then,  that  the  thermanalytic  force  being 
antagonistic  to  the  chemical  force,  and  that,  step  by  step,  the  com- 
pound is  analyzed  to  its  elementary  molecules,  it  foUows  that  as  the 
basylous  molecules  are  separated,  so  the  stylous  or  acid  molecules  must 
be  also  liberated  or  separated.  The  following  experiments,  whilst 
establishing  this  fact,  are  merely  taken  as  examples  from  many  others 
in  consideration  of  their  simplicity. 

It  becomes  evident  that,  in  working  under  pres^ire,  there  cannot 
be  any  indications  of  molecular  change  better  than  colour  tests,  similar 
to  those  which  serve  us  so  weU  in  ordinary  qualitative  analysis,  and, 
therefore,  it  is  better  to  confine  ourselves,  as  much  as  possible,  to  such 
reactions. 

There  are  many  instances  which  may  be  cited  as  setting  forth  with 
the  dissociation  of  the  stylous  group,  but  which  would  not  come  under 
my  designation  of  dissociation,  because  they  are  attended  with  perma- 
nent decomposition.  As  an  example  of  dissociation,  let  us  take  the 
well-known  salts  formed  by  the  combination  of  chromic  acid  and 
# 

*  Report  on  the  Molecular  Dissociation  by  Heat  of  Compoundfl  in  Solution. 
Proceedingfl  Koyal  Irish  Academy,  Vol.  i.,  Ser.  ii.,  Science,  p.  169. 

t  On  the  Action  of  Heat  upon  Solutions  of  Hydrated  Salts.  Proceedings 
Royal  Irish  Academy,  Vol.  i.,  Ser.  ii..  Science,  p.  247. 


TiCHBORNE — On  the  Dissociation  of  Molecules  in  Solution.    231 

potassium.  Solutions  of  the  yellow  or  neutral  ohromate  of  potassium, 
and  also  the  red,  or  acid,  ohromate  of  potassium,  were  made  of  such  a 
strength  that  10,000  parts  contained  an  equivalent  of  each  salt.  In 
other  words,  the  yellow  solution  of  chromate  of  potassium  contained 
194*5  parts  of  salt  in  the  10,000  parts,  and  the  red  chromate  contained 
147*5  parts  in  the  10,000,  hut  each  solution  contained  the  same  amount 
of  the  colour-producing  molecule,  or  the  chromic  acid,  only  in  different 
conditions  of  saturation.  If  we  take  1000  parts  of  the  yellow  solution 
of  chromate  of  potassium,  we  find  that,  even  at  the  ordinary  tempera- 
ture, 15*5  C,  partial  dissociation  has  occurred.  Presuming  that  wo 
have  started  with  perfectly  neutral  crystals,  we  shall  find  that,  on  the 
addition  of  a  volumetric  solution  of  soda,  the  colour  hecomes  lighter 
until  a  quantity  has  heen  added  which  represents  -059  of  red  chromic 
salt ;  therefore  we  are  justified  in  coming  to  the  conclusion  that  at  a 
temperature  of  15*5,  sufficient  of  the  acid  is  dissociated  from  the  neu- 
tral salt  to  form  that  quantity  of  the  acid  salt — ^that  in  fact  there  is 
even  a  slight  or  partial  dissociation  in  the  act  of  solution.  If  this 
neutral  solution  is  then  hrought  to  the  hoiling  point,  and  we  use 
some  consi^erahle  hulk  for  the  experiment,  we  shall  find  that  a  marked 
decomposition  has  taken  place  in  the  salt,  as  evidenced  in  the  change 
of  colour.  In  a  few  carefully  conducted  experiments  it  was  found 
that  it  gave  a  decomposition  which  averaged  ahout  Vrth  of  the  yellow 
salt  present ;  e,  g.y  1000  parts  of  the  solution  of  the  yellow  salt,  men- 
tion^ above,  were  brou^t  rapidly  to  the  boil  in  a  fiask  furnished  with 
a  long  neck,  so  as  to  condense  the  steam  which  flowed  back  into  the 
flask.  Another  1000  parts  of  the  yellow  solution  was  then  placed  into 
another  flask,  and  at  a  temperature  of  15-5  C.  A  standard  solution  of 
Bulpburic  acid  was  added,  degree  by  degree,  until  the  exact  colour 
was  obtained,  which  agreed  with  the  boiling  solution  of  chromate.  The 
standard  solution  contained  one-half  an  equivalent  in  10,000  parts  of 
sulphuric  acid,  and  fifty-one  degrees  had  been  used,  which  corresponded 
wiUi  0*75  parts  of  the  red  salt  formed,  and  which  also  represented 
'51  parts  of  chromic  anhydride  dissociated  at  a  temperature  of  100°  C. 
from  19*45  parts  of  the  salt. 

If  the  neutral  solution  of  yellow  chromate  be  now  inclosed  in  a 
sealed  tube  (such  a  one  as  described  in  my  previous  paper*),  and  sub- 
mitted to  a  high  temperature,  say  250°  C,  it  would  appear  that  about 
75  per  cent,  of  the  yellow  chromate  will  be  converted  into  the  red 
salt.f  The  experiments  in  connexion  with  chromates  may  throw  some 
considerable  light  upon  one  of  those  mysteries  of  the  photographic  art 
which  up  te  the  present  time  has  not  been  properly  or  satisfactorily 
explained.  One,  if  not  the  most  important,  method  of  taking  sun- 
pictures  is  based  upon  the  action  of  light  upon  a  film  of  gelatine,  contain- 
ing a  little  red  chromate  of  potassium.  Such  a  mixture  is  highly 
*  

♦  1.  c,  p.  250. 

t  Chromic  acid  is  said  to  form  four  salti  with  potaadimx :  KsOCrOs,  Ks02Cr03 
Kj03CrO.,,  and  Ka04CrO». 


232  Proceedings  of  the  Royal  Irish  Academy. 

senBitive  to  light,  the  gelatine  becoming  insoluble  under  the  faintly 
oxidizing  tendency  of  the  chromic  salt.  This  film  is  also  found,  however, 
to  be  sensitive  to  other  agencies,  and  it  has  been  this  phenomenon 
that  has  puzzled  photographers.  Such  a  film  becomes  insoluble  by 
moisture,  heat,  and  lapse  of  time.  It  would  appear  in  fact  that  light  is 
not  absolutely  necessary  to  bring  about  the  change.  The  experiments 
detailed  will  go  far  to  explain  all  these  phases  of  the  phenomenon. 
We  find  that  moisture  means  solution,  or  the  mobility  of  the  chemical 
molecules,  which  is  absolutely  necessary  to  chemical  change,  and  that 
solution,  even  at  ordinary  temperatures,  means  a  partial  decomposi- 
tion, however  infinitesimal  that  decomposition  may  be.  But  when 
we  add  time  to  this,  there  is  no  limit  to  put  upon  the  results  of  this 
decomposition.  We  also  see  how  greatly  the  partial  decomposition  of 
the  chromic  salt  is  accelerated  by  each  increment  of  heat,  and  therefore 
we  can  understand  how  such  a  film  would  be  sensitive  to  temperature. 

The  salts  used  in  these  experiments  were  not  those  ordinarily  found  in 
commerce,  because  their  neutrality  is  not  sufficiently  well  marked  for  the 
determination  of  the  delicate  reactions  detailed  above.  The  yellow  chro- 
mate  was  found  particularly  unreliable  in  this  respect.  It  was  purified  by 
adding  a  few  drops  of  caustic  potash,  and  re-crystallizing  twice.  The 
bichromate  was  purified  by  adding  a  few  drops  of  dilute  sulphuric 
acid,  crystallizing  to  a  slight  extent,  and  rejecting  these  first  crystals, 
and  then  taking  off  a  second  and  more  extensive  crop  of  crystals. 
These  last  crystals,  on  re-crystallization,  yielded  a  salt  sufficiently  pure 
for  the  experiments.  Solutions  made  with  the  two  salts  exhibited  a 
marked  difference  in  shade  from  the  commercial  crystals. 

Another  illustration  of  the  dissociation  of  the  acid  molecule  ifl  well 
shown  in  the  uranic  nitrate :  uranic  nitrate  is,  if  evaporated  to  dryness 
and  submitted  to  heat,  decomposed  into  pure  uranic  hydrate  and 
a  basic  nitrate.  It  would  probably  therefore  be  a  salt  which  would 
easily  dissociate  in  solution,  even  at  a  moderate  temperature,  but  at 
the  same  time,  it  affords  a  colour  test  of  the  dissociation  of  the  acid 
molecule,  because  the  presence  of  free  nitric  acid  causes  in  the  bright 
yellow  solution  of  uranic  nitrate  an  orange  coloration. 

It  is  stated  that  a  solution  of  uranic  nitrate  is  decomposed  at  a 
moderate  heat  with  the  deposition  of  a  precipitate,  the  composition  of 
which  has  not  been  determined.    I  have  not  found  this  to  be  the  case, 
however,  in  sealed  tubes;  for  it  seems  to  bear  with  impunity  a  tempera- 
ture which  must  be  close  upon  130°  C.  Therefore  we  are  led  to  infer 
that  such  a  decomposition  results  from  the  loss  of  nitric  acid.  When  such 
a   solution  is  heated  under  these   conditions,  it  gradually  becomes 
more  and  more  orange.  Many  other  instances  may  be  given  of  the  dis- 
sociation of  the  acid  molecule,  and  we  need  hardly  go  further  than 
the  decompositions  resulting  from  the  dissociation,    when  either  the 
acid  or  the  base  is  volatile.     In  the  case  of  carbonic  anhydride   this 
dissociation  results  in  the  production  of  basic  carbonates,  such  as 
Carbonate  of  Magnesium  ((MgCO,)  ,Mg05H,0). 
Carbonate  of  Zinc  (ZnCOs  (ZnO),  3H,0). 
Carbonate  of  Lead  (6PbCO,PbOH,0.) 


TicHBORNE — On  the  Dissociation  of  Molecules  in  Soluti&tu    233 

In  the  case  of  a  volatile  base  and  acid  such  as  carbonate  of  ammonium, 
we  have  a  partial  dissociation,  attended  with  both  loss  of  acid  and 
base,  but  which  from  the  tendency  to  assimilate  the  acid  molecule  M' 
H  A''  is  productive  of  a  curious  decomposition.  The  two  following  ex- 
periments will  illustrate  this  in  a  striking  manner. 

They  are  performed  with  the  most  permanent  of  the  ammonium 
salts,  the  sulphate  (NH4),S04,  and  the  most  unstable,  viz.  (NH4),C0„ 
the  normal  carbonate.  We  find  that  at  a  very  slight  increase  of  tem- 
perature the  sulphate  molecule  is  no  longer  permanent.  Crystals  of 
sulphate  of  ammonium  were  taken  which  were  perfectly  pure  and  neutral. 
A  poreclain  crucible  was  filled  with  these  crystals,  and  a  sufficient 
quantity  of  water  was  added  to  moisten  them.  The  crucible  was 
placed  in  a  water  bath  provided  with  a  thermometer,  and  covered  with 
a  beaker,  a  piece  of  blue  litmus  was  placed  upon  the  surface  of  the 
moistened  sulphate,  and  a  piece  of  red  litmus  in  the  beaker.  At  a 
temperature  16°  C.  a  slight  decomposition  took  place,  but  at  20°  C. 
the  tension  of  the  gaseous  base  was  so  raised  that  rapid  decomposition 
set  in,  the  litmus  paper  in  the  Belt  becoming  red  from  the  formation 
of  I7H4  HSO4  and  the  Htmus  paper  in  the  beaker,  which  was  originally 
red,  becoming  blue  from  evolved  ammonia. 

Water  is  essential  to  such  a  phenomenon,  and  no  decomposition  can 
be  perceived  with  the  dry  salt,  under  such  a  condition,  mobility  of  the 
atoms  being  essential. 

Carbonate  of  ammonium  NH4  CO,  was  formed,  by  treating  ordinary 
carbonate  with  ammonia,  and  the  result  was  a  moist  salt,  but  still 
in  the  form  of  a  powder.  It  was  placed  in  a  vessel  the  sides  of  which 
were  perfectly  cleaned :  this  vessel  was  then  surrounded  with  a  freezing 
mixture  of  a  considerable  power,  and  at  a  temperature  of  about  4°  C.  it 
became  nearly  odourless,  and  at  a  much  lower  temperature  perfectly  so. 
Thus  we  find  that  the  most  permanent  salt  of  ammonia  is  in  a  state  of 
tension  thus : 


Molecule  of  Sulphate  of 
Ammonium. 


Molecule  of  Sulphate  of  Ammonium  dissociated  hj  heat  into  two  molecules. 

a,  t  A.  PBGC,  BBB.  II.,  VOL.   II.,  SCTBNCB.  2  I 


234  Proceedings  of  the  Royal  Irish  Amdemy. 

or  it  may  be  represented  by  the  equation 

(NH0,8O4  =  NH4H  SO,  +  NH,. 
and  the  second  experiment  by  the  equation 

(NH,),  CO,  =  NH4  H  CO,  +  NH,. 

If  we  substituted  a  less  volatile  base  in  such  a  reaction  we  ought 
only  to  haye  the  phenomenon  which  is  generally  understood  under 
the  designation  of  dissociation.  The  result,  however,  in  this  case  is  a 
permanent  decomposition. 

Nitrates  when  heated  under  pressure  with  oxidizable  metals  are 
rapidily  decomposed,  and  the  surface  of  the  metal  corroded.  Many  of 
the  boiler  accidents  have  been  probably  so  caused ;  for  we  may  ex- 
tend these  remarks  to  the  other  salts  found  in  water,  although  none 
seem  so  energetic  upon  the  surface  of  the  metal  as  the  nitrates,  owing 
to  the  ease  with  which  that  acid  yields  its  oxygen. 

We  cannot  conclude  this  part  of  our  subject  without  pointing  out 
how  strongly  these  researches  upon  the  dissociation  of  the  acidulous 
and  basylous  molecules  bear  upon  the  technical  processes  upon  which 
the  arts  and  manufactures  rest.  Le  Blanc's  ingenious  but  round- 
about process  for  the  production  of  soda  and  hydrochloric  acid,  seems 
threatened  by  dissociation,  and  already  the  process  for  the  production 
of  chlorine  directly  from  hydrochloric  acid  and  air*  is  based  upon 
similar  reactions  to  those  described  in  this  report. 


•  "  On  a  New  Chlorine  Process  without  Manganese."   B7  'Ejoxkt  Dbacof, 
F.  C.  S.,  British  Association.    Beport,  1870,  Transactions  of  the  Sections,  p.  54. 


O'Meara — Report  on  the  Irish  Diatomm-ew,  235: 


XXXYII. — ^Repobt  on  the  Ibish  Diatomacks.     By  the  Ret.  ExraENX 
O'Meaka,  M.  a.     Part  I.     (With  Plates  26  to  35.) 

[Bead  June  28, 1875.] 

It  is  now  just  a  century,  since  in  1773,  0.  F.  Miiller  discovered  the 
first  known  diatomaceous  form ;  nor  was]  it  till  ten  years  after,  the 
same  distinguished  author  was  able  to  add  two  new  forms  to  the  list. 
In  the  year  1824  Agardh  published  his  ''Systema  Algarum;"  and 
then  the  number  of  species  was  forty-nine,  comprehended  imder  eight 
genera.  But  if  in  diis  province  of  Natural  Science  the  progress  was 
slow  during  the  first  half  century,  it  has  been  very  rapid  in  the  last, 
owing  not  only  to  the  number  of  eminent  labourers  in  this  field  of 
research,  but  also  to  the  greatly  improved  means  of  investigation. 
The  number  of  species  in  Europe  alone,  as  computed  by  Babenhorst 
in  his  index,  is  about  4000.  This  may  be  beyond  the  mark,  but 
certainly  Pfitzer  is  far  short  of  it  when  he  fixes  the  total  number  of 
known  species  at  about  1000.  It  is  not  necessary  to  enumerate  the 
many  authors  to  whose  useful  labours  the  students  of  this  branch  of 
Science  are  indebted,  but  special  notice  should  be  made  of  Kiitzing, 
who  explored  the  whole  surface  of  the  globe ;  and  of  Ehrenberg,  who, 
not  content  with  the  same  ample  field  of  investigation,  extended 
his  researches  into  the  bowels  of  the  earth.  But  no  authors,  perhaps, 
have  contributed  so  much  to  the  extent  and  accuracy  of  our  know- 
ledge, as  those  who  have  restricted  their  labours  to  ^ome  special 
families,  or  to  the  collection  and  examination  of  the  forms  incidental 
to  some  country  or  district.  The  treatise  on  the  DiatomacesB  of  the 
Clyde  has  earned  for  Gregory  an  imperishable  name.  The  Austrian 
forms  have  been  described  by  Grunow.  The  Prussian  by  Schuman. 
The  Danish  by  Heiberg.  Those  of  Sweden  and  Norway  by  Clete, 
and  those  of  Great  Britain  by  Smith  in  his  admirable  Synopsis. 

No  country  would  appear  more  favourable  to  the  growth  of  these 
forms  than  our  own,  with  its  extensive  sea-coast  indented  with 
numerous  bays,  its  rivers  and  lakes,  and  mountain  ranges.  And  yet 
it  is  strange  that  Smith,  an  Irishman,  at  least  labouring  professionsJly 
in  Ireland,  should  have  done  but  little  in  exploring  its  resources,  as 
appears  from  the  fact  that,  in  the  case  of  389  forms  figured  and 
described  by  him  as  British,  there  are  not  more  than  about  one 
hundred  for  which  Irish  localities  have  been  assigned.  Hence  it 
might  be  supposed  that  the  cHmate  of  Ireland  is  not  favourable  to  the 
growth  of  Diatomaceous  forms — an  impression  which  is  not  justified 
by  the  fact,  as  I  hope  to  prove  by  the  present  work. 

For  many  years  the  intervals  of  professional  engagements  had  been 
devoted  by  me  to  the  collection  and  study  of  the  Irish  Diatomacese ; 
and  a  large  amount  of  material  had  been  gathered  and  arranged  when 

B.  I.  A.  ntoc,  8BS.  n.,  VOL.  n.,  sciBircB.  2  K 


236  Proceedings  of  the  Royal  Irish  Academy. 

I  was  favoured  with  the  request  of  the  Boyal  Irish  Academy  to 
prepare  a  list  of  the  forms  to  be  met  with  in  this  country — a  request 
with  which  I  unhesitatingly  complied.  Had  I  been  content  with 
furnishing  an  inventory  of  the  forms  I  had  found,  the  task  I  had 
undertaken  might  have  been  speedily  performed' ;  but  my  anxiety  was 
to  render  the  work  as  complete  and  as  useful  to  my  fellow-students  as 
I  could,  and  as  worthy  of  the  re^tation  of  the  Royal  Irish  Academy 
as  it  was  possible  for  me  to  make  it.  "With  this  view  I  determined  to 
explore-  new  looalitieB,  and  to  search  more  carefully,  districts  I  bai 
previously  exammed.  I  was  anzioua  also  to  avail  myself  of  the 
kbours  c^  the  most  distmguished  authors  on  the  subject,  and  was 
therefore  obliged  to  acquire  a  knowledge  of  languagos  witili  whi«h  I 
waa  previously  uaaoquBinted. 

Eor  all  1^8)  time  was  Mqmred,  and  I  refer  to  the  subject  fw  tha 
puipose  of  showing  that  the  long  period  that  has  dapeedsinieo  tho  taak 
was  undertaken  has  been  busOy,  and  I  hope  not  fpuitlessly,  occupied. 
No  authentically  named  speoinnns  were  available ;  and  this  proved  to- 
me a  source  of  much  additional  labour  and  delay.  Those  who  a«e 
practically  acquainted  with  the  Diatomacesd  are  aware  how  difficult  it 
M  sometimes  under  the  most  favourable  ciroumstances  to  identify  a 
form.  The  difficulty  is  enhanced  in  cases  in  which  the  original 
form,  observed  under  the  disadvantagB  of  inferior  instruments,  has 
been  inadequately  described ;  and  when  a  mistake  has  been  made 
in  the  figure  or  the  description,  the  only  satiaf  actory  means  of  identifl- 
eation  is  the  inspection  of  the  epecimen.  Hence  some  idea  may  be 
formed  of  the  difficulty  and  delay  arifdng  from  the  oi^umstance 
of  there  being  no  authentic  spedmens  preserved  in  tfny  of  the 
Collections  or  Herbaria  of  Dublm.  Many  are  the  friendlr  who  have 
kindly  assisted  me  in  the  prosecution  of  this  work,  but  speoial  aeknow- 
ledgments  on  my  part  ave  doe  to  Professor  E.  Perceval  Wright,  M.D., 
not  only  for  the  loan  of  collections  but  also  of  books  and  objectives,  to 
Sev.  Maxwell  H.  Close,  and  A.  G.  More,  Esq,,  whose  collections  have 
added  numerous  forma  to  my  Hst,  as  well  as  new  localities  for  many 
others;  and  also  to  Dr.  David  Moore,  whose  many  and  valuable 
collections  were  kindly  placed  at  my  disposal. 

The  name  of  Bacillanacesd  was  employed  to  designate  this  group  of 
organisms  at  a  time  when  little  of  their  structure  and  habits,  except 
their  outward  form,  was  known ;  and  Pfitzer  maintains  that  this  desig- 
nation should  be  retained  because  of  its  priority :  but  I  have  adopted 
the  more  modem  name  of  Diatomacee,  not  only  because  it  is  more 
pronounceable,  but  socially  because  it  is  more  characteristi4f  and  more 
generaUy  known. 

The  question,  what  is  the  proper  position  of  the  Diat<»naoe8B  in  the 
olaseiflcation  of  organized  beings,  has  been  variously  answered.  The 
first  known  species-  were  by  tibuBir  discoverers  included  amongst  the 
Conferraoeffi;  l^e  eztraoxdinary  movements,  however,  of  Baoillaria 
paadllifer,  noticed  by  Miiller,  indaoed  that  author  to  idmitify  it  with 
the  genus  Yilnio ;  and  tha  positiion  aasigned  to  this  Uftm^  a»  well  as 


O'Meara — Bepori  on  the  In$h  Diaiamacew.  237 

the  rapid  motioii  by  which  it  is  charactemed,  ^ay  have  insensibly 
inelined  saceeeding  observers  to  assign  to  the  Diatomaeca  generdly  a 
place  in  the  Animal  Eixigdom.  This  theory  is  supported  by  ilie 
aatherlty  of  the  iUnstrionfi  Ehrenberg,  who  regarded  tiie  niiiiieroas 
^^oboles  noticeaUe  in  the  cells  as  so  many  stomanhs,  and  tiierefore 
gave  to  a  gronp  embracing  these  and  other  forms  the  general  designa- 
ticm  of  Poiygastricse.  Bnt  notwithstanding  the  deference  jns^  due 
to  so  great  an  authority,  more  recent  observers  are,  I  muf  mtf, 
xmanunonsly  of  opinion  that  the  Biatomacen  belong  to  the  Yegetable 
Kmgdom — ^an  opinion  sustained  by  the  analogy  which  tbe  fcmixs  of 
this  gnmp  exinbit  as  regards  their  general  stractore,  aa)d  more 
especially  by  the  mode  of  reproduction  which  they  possesv  in  eommon 
wxtli  other  organisms  genendly  regarded  as  vegetable. 

Tha  Motum  of  the  Diatoma^ea. 

One  of  the  first  phenomena  which  attracts  the  notice  of  the  students 
of  the  Biatomaccte  is  the  extraordinary  power  of  motioii  with  which 
the  fmstules  are  endowed.  To  account  for  tids  motion,  various 
theories  have  been  suggested,  reducible  to  two  general  classes.  By 
some  it  has  been  supposed  that  in  the  process  of  imbibing  water  Con- 
taining nourishment  and  expelling  what  is  superfluous,  currents  arc 
produced  which  have  the  effect  of  propelling  the  fmstules  backwards 
and  forwards  through  the  water.  As  concerns  this  hypothesis,  I  qufto 
concur  with  the  opinion  expressed  by  Ralf  s,  that  it  should  be  regarded 
rather  as  a  figment  of  the  imagination  than  founded  on  the  observation 
of  facts.  Others  have  suggested  that  the  fmstules  are  filmished  with 
special  organs  of  locomotion.  The  occurrence  of  hair-like  processes 
on  the  fmstules  has  afforded  a  colourable  reason  for  such  a  statement ; 
they  are,  however,  only  occasional,  and  have  the  appearance  of 
parasitic  growth,  rather  tiian  of  normal  organs  of  the  plant.  Ehrcn- 
berg  conceived  that  a  pedal  organ  was  extmded  from  what  he  regarded 
ss  an  orifice  in  the  centre  of  the  valve :  but  so  far  from  the  exis- 
tence of  such  an  organ  having  been  satisfactorily  sustained,  the  fact 
that  what  that  eminent  observer,  as  well  as  others  of  deservedly  high 
reputation,  considered  to  be  an  opening,  is  now  generally  regarded  as 
a  thickening  of  the  silicious  plate,  is  fatal  to  Ihe  theory.  So  whilb 
the  motion  of  the  Biatomacc&e  continues  to  excite  attention,  it  must  be 
confessed  that  the  mechanical  agency  by  which  the  motion  is  effects 
riemainB  unexplained. 

Structure  fff  th$  Cell. 

There  is  one  remarkable  feature  iia  the  Btrdotore  <yf  lAke  Wir 
tomaoe»  which  distingniehes  them  fteUi  coghate  ofgfanlstiiis,  that  is,  the 
fact  that  the  cell  is  invested  -^th  a'  sQieious  covering^  eonsSstisbg 
of  two  distmct  jdates;  moiV)  or  less  paMllel  to  ono  anothei*,  and  heM 
together  by  a  rim  or  hoop.    This  silicious  covering  has  b^en  ap^^d- 

2K2 


238  Ptvceedings  of  the  Boyal  Irish  Academy. 

priately  assimilated  to  a  pill-box,  coiisisting  of  the  box  itself  and  the* 
cover  which  slips  over  it ;  and  if  wo  suppose  the  cover  to  be  of  the 
same  depth  as  the  box,  or  nearly  so,  we  have  a  stmcture  on  a 
large  scale  which  nearly  resembles  the  silicious  covering  of  such 
Diatomaceous  species  as  possess  a  circular  form,  and  which  with  some 
modification  may  be  taken  to  illustrate  the  general  plan  on  which  the 
silicious  part  of  the  cell  of  Diatoms  is  constructed.  In  the  larger 
forms  it  may  easily  be  noticed  that  one  valve  of  the  frustule,  with  its 
accompanying  rim  or  hoop,  is  smaller  than  the  other  into  which  it  fits, 
as  the  slides  of  a  telescope  fit  into  one  another.  It  has  been  supposed 
that  in  the  parent  frustule  the  two  valves  are  of  the  same  size,  and  that 
the  diminution  in  the  dimensions  of  one  valve  is  owing  to  the  fact  of  its 
being  developed  within  the  rim  of  the  primary  valve,  and  is  conse* 
quently  smaUer  than  it  by  the  thickness  of  the  nm.  Pfitzer,  however, 
has  remarked  that  in  some  cases  at  least  the  difference  in  size  ia 
noticeable  in  the  mother  cell,  in  which  one  valve  is  secreted  in  the 
first  instance,  and  then  the  opposite  valve  is  formed  within  the  former. 
This  remark  is  worthy  of  notice  and  should  be  borne  in  mind  when 
cases  of  conjugation  come  under  view,  in  order  to  ascertain  whether 
the  occurrence  is  casual,  or  whether  the  same  process  takes  place  in 
the'  other  species  of  Diatomacese.  To  the  distinguished  author  just 
muned  belongs  the  merit  of  having  contributed  more,  than  any  other 
to  the  extent  and  accuracy  of  our  knowledge  concerning  the  various 
parts  and  disposition  of  the  cell-contents.  There  is  first  the  plasm-sac, 
consisting  of  a  fine  colourless  plasm,  forming  a  closed  sac  of  the  shape 
of  the  cell,  and  in  which  the  cell-contents  are  enveloped.  It  is  often 
very  difficult  for  the  observer  to  make  himself  certain  of  the  existence 
of  tills  sac,  because  its  refractive  power  differs  but  slightly  from  that 
of  water,  but  the  structure  becomes  apparent  immediately  on  the 
application  of  dilute  hydrochloric  acid.  The  effect  of  this  re-agent 
is  to  produce  an  instantaneous  contraction  of  the  sac,  which  at  first,  as 
it  recedes  from  the  cell-waU,  preserves  the  form  of  the  cell  and  still 
maintains  connexion  with  it  by  means  of  a  few  pellucid  threads,  but 
after  some  time  it  becomes  contracted  into  a  round  mass.  This  result 
is  accomplished  most  effectively  by  the  use  of  osmic  add  at  the 
strength  one  per  cent.  Iodine  gives  a  bright  yellow  colour  to  the 
plasm-sac.  'Within  the  plasm-sac,  and  in  close  proximity  to  it,  is  the 
structure  to  which  Pfitzer  has  given  the  name  of  Endochrome- 
plates,  varying  in  number  and  position  in  the  various  genera. 
Some  possess  two  of  these  plates,  others  only  one.  In  the  Navicul© 
these  plates,  two  in  number,  lie  one  at  either  side,  the  middle  of  the 
plate  corresponding  with  the  middle  of  the  hoop  or  connecting  band, 
whence  they  pass  on  either  side  towards  the  median  line,  leaving  a 
smaljl  narrow  space  down  the  middle  of  the  valve  free ;  in  other  genera 
th^re  is  but  one  such  plate,  variously  disposed.  They  consist  of  a 
thick  Bubstancei  and  are  of  the  same  colour  thoroughout,  varying  from 
ligl^t  yellow  to  dark  yellowish  brown.  The  plasm  of  which  these 
l^ate^.con^t  differs  in  density  irom  the  plasm  which  forms  the 


O'M EASA — Report  on  the  Irish  DiatomacetB.  23& 

plasm-sac  and  the  structure  which  is  called  the  middle-mass.  In  case 
the  normal  condition  of  the  cell-contents  be  disturbed  by  fracture  of 
the  silicious  epiderm,  the  endochrome  plates  go  together,  and  never 
<onmiingle  with  the  material  of  the  _  plasm-sac.  If  the  colouring 
matter  be  discharged  by  alcohol,  the  demarcation  of  the  endochrome 
plate  from  the  rest  of  the  plasm  can  be  readily  distinguished. 
Within  the  folds  of  the  endochrome  plates  is  fonnd  in  some  a 
<;ollection  of  plasm,  which  Ffitzer  calls  the  "middle  plasm-mass," 
described  by  Ehrenbcrg  as  resembHivg  "  the  embyro  in  an  egg; "  in 
the  Naviculse  it  forms  generally  an  irregular  quadrangle.  Yacuolcs  and 
-oil  globules  occur  imbedded  in  this  middle  plasm-masS)  and  appear 
^distinctly  in  consequence  of  their  strong  refractive  power.  In  the 
middle  of  this  plasm-mass  a  central  vesicle  is  observable  in  some 
genera,  but  is  not  equally  distinct  in  all  species.  And  although  in  some 
cases  it  cannot  be  discovered,  even  with  the  most  skilful  management, 
Pfitzer  considers  that  nevertheless  the  statement  of  Luders  may  be 
^correct,  that  no  Diatomaceons  cell  is  destitute  of  such  a  vesicle,  because 
although  in  many  cases  no  such  structure  can  be  detected  by  ordinary 
means,  it  becomes  apparent  by  the  application  of  re-agents,  the  most 
effective  for  the  purpose  being  dilute  hydrochloric  acid. 

Besides  the  parts  already  specified,  there  have  been  observed  in 
some  of  the  Dia^maceae  a  water-like  fluid  substance,  and  oQ-globules, 
varying  in  size.  These  latter  occur  swimming  freely  in  the  cell,  but 
in  greater  number  upon  the  inner  surface  of  tiie  plasm-sac.  In  con- 
sequence of  their  strongs  refractive  power  they  strike  the  eye  at  once, 
and  are  changed  into  a  black  colour  by  the  use  of  osmic  acid.  As 
they  readily  combine,  they  have  no  investing  pellicle.  It  is  thought 
that  in  proportion  as  the  oil-globules  abound,  the  cells  have  suffered 
from  the  want  of  pure  water,  and  that  the  appearance  of  the  larger 
oil-globules  is  a  sign  that  the  ccU  has  attained  its  full  maturity, 
and  that  its  resources  have  been  exhausted.  The  oil-globules  afford 
a  means  of  answering  the  question  whether  the  ceU  contents  are  of  a 
watery  or  of  a  gelatinous  consistency.  In  favour  of  the  former  view, 
Pfitzer  refers  to  the  fact  that  very  weak  acid  produces  an  immediate 
shrinking  of  the  plasm-sac,  and  also  to  his  observation  that  the  oil- 
globules  can  be  moved  about  with  facility,  which  could  not  occur 
if  the  surrounding  matter  were  of  a  gelatinous  thickness.  And  this 
opinion  of  Pfitzer  has  been  corroborated  by  Focke,  who  discovered 
that  the  oil-globules,  in  consequence  of  their  light  specific  gravity, 
accumulate  on  the  upper  surface  of  the  cell,  and  change  their  position 
in  case  the  frustule  is  turned  upside  down. 

The  Reproduction  of  the  Diatomacea 

Is  a  subject  of  deep  interest,  requiring  some  explanatory  remarks. 
The  ordinary  mode  of  increase  is  by  self-division,  as  it  has  been 
termed.  The  cell-contents  within  the  enclosure  of  the  silicious 
•epiderm  separate  into  two  distinct  masses.     As  these  develop  they 


240  Proceedings  of  the  Boyal  Irish  Acedemy. 

ptuh  the  Talyes  of  tho  mother-coll  more  and  more  widely  asunder. 
A  new  stlicioiis  valye  k  secreted  by  each  of  the  two  masses,  on  the 
side  opposite  to  the  original  valres.  And,  when  this  process  has  been 
completed,  two  distinct  frostnles  are  formed,  the  silicions  valves  in 
each  being  one  ol  the  valves  of  the  parent-cell,  and  a  newly  secreted 
valve  apposed  to  it.  During  the  active  life  of  the  cell  this  process  of 
self-division  is  oontiniied,  and  is  rapidly  completed.  On  this  subject 
Smith  observes,  **  I  have  been  unable  to  ascertain  the  time  occupied  in 
a  single  act  of  self -division ;  but,  supposing  it  to  be  completed  in 
twenty-four  hours,  we  should  have  as  the  progeny  of  a  sin^  frustule 
the  amagJTig  number  of  one  thousand  millions  in  a  single  month — a 
circumstance  which  will,  in  some  degree,  explain  the  sudden,  or,  at 
least,  rapid  appearance  of  these  organisms  in  localities  where  they 
were,  but  a  short  time  previously,  either  unrecognised  or  sparingly 
diifused." — British  Diatomaceie,  vol.  i.,  p.  25. 

It  seems  probable  that  the  Diatomaceas  are  sometimes  reproduced 
by  zoospores.  Babenhorst  records  his  having  observed  a  specimen  of 
Melosira  vaiians,  in  which,  from  the  sporangial  frustule,  tiiere  issued 
what  appeared  to  be  germs,  and  has  described  the  process.  Dio 
Sosswasser  Diatomaceen,  T.  x.,  £g.  18  c.  A  similar  occurrence  wa» 
noticed  by  myself  in  1858,  in  the  case  of  Pleurosigma  Spencerii:  and 
Gastracane  has  recorded  two  or  three  observations  of  the  same  kind. 
So  far  as  I  am  aware,  the  development  of  these  zoospores,  if  such  they 
be,  has  in  no  case  been  traced  through  its  successive  stages  to  its 
ultimate  result ;  but  there  is  nothing  unreasonable  in  the  presumption 
that  the  phenomenon  may  be  a  phase  of  the  reproductive  process. 

Another  mode  of  reproduction  in  the  Diatomaceae  is  by  conjugation,. 
of  which,  according  to  Smith,  there  are  four  distinct  phases.  First.  The 
union  of  two  parent  frustules  issues  in  the  formation  of  two  sporangia. 
Second.  Two  parent  frustules  produce  only  one  sporangium.  Third.  A 
single  frustule  develops  a  single  sporangium.  Fourth.  A  single  parent 
frustule  produces  two  sporangia.  In  the  first  stage  of  the  conjugative 
process,  a  mucous  sac  is  secreted  by  the  parent  frustules,  within 
which  the  sporangia  are  developed ;  these  sporangia,  in  some  cases, 
lie  parallel,  and  in  other  species  at  an  angle  with  the  parent  frustules 
or  valves,  as  the  case  may  be.  A  phase  of  conjugation,  quite  distinct 
from  the  four  lust  referred  to,  came  under  my  notice,  many  years  ago, 
in  the  ease  of  I)iatoma  vulgare.*  I  observed  numerous  instances  of  tiie 
long  chain  of  concatenated  frustules  in  their  normal  condition  with  a 
sudden  jerk  fold  themselves  into  a  solid  mass.  In  a  very  brief  period 
a  mucous  sac  was  seen  to  develop  itself,  inclosing  the  whole  mass  of 
frustules,  and  in  some  cases  enveloping  forms  of  a  different  species 
which  happened  to  be  in  immediate  proximity.  By  degrees  the  mu- 
cous sac  pushed  itself  forward,  sometimes  in  a  single  projection,  some- 
times in  two,  and  into  these  prolongations  the  cell-contents  of  the 


♦  Natural  Ilirtory  Review,  1859,  vol.  vi.,  page  90,  PL  ix. 


O^Meara — Eeport  an  the  Irish  DiatomacecB.  241 

frashtles  were  ponred ;  the  prolengations  became  gradually  more  and 
more  confl^aicted  at  the  base,  until  ultimately  they  were  completely 
eut  off  from  the  mucous  sac,  in  which  the  Irustnles  remained  folded,  in 
a  state  of  perfect  inanition.  The  process  described  was  completed 
within  the  space  of  a  few  hours,  so  that  in  innumerable  instances  I  was 
able  to  trace  it  from  beginning  to  end — ^that  is,  from  the  commence- 
ment of  conjugation  up  to  the  foimation  of  the  sporangia.  Smith  refers 
to  cases  of  Cocconema  cistula,  and  also  of  Synedra  radians,  haying  been 
found  aggregated  in  great  numbers  and  enclosed  in  mucoT»  sacs  simi- 
lar to  what  has  be^i  described  in  tlie  case  of  I>iat(»na  vulgare ;  and 
all  three  cases  seem  to  me  to  rexo^sent  the  same  phase  of  conjugation : 
ttid  I  am  diq>08ed  to  think  that,  as  in  Diatoma  vulgare,  so  in  the 
other  two  cases,  the  encysted  &^istules  wei«  not,  as  Smith  considered 
them,  young  fmstules  in  course  of  development  from  a  sporangium, 
but  parent  fmstules  preparing  to  produoe  sporangia. 

Instances  of  conjugation  in  any  of  its  varied  forms  are  rarely  to  be 
met  with.  When  Smith  published  his  Synopsis,  in  1856,  cases  had 
been  observed  in  thirty  species,  ineluded  in  seventeen  distinct  genera ; 
and  during  the  interved  of  fifteen  years  that  had  elapsed  when  Pfitzer 
published  his  work,  **  Tiber  Bau  und  Entwicklung  der  Bacillariaceen," 
only  twenty-eight  cases  had  been  added  to  the  Ust,  exclusive  of  that 
of  Biatoma  vulgare,  making  a  total  of  sixty-one.  This  remarkable  fact 
Smith  thus  endeavours  to  account  f or :  ** During  conjugation  the  process 
ai  self-division  is  arrested,  the  general  mucous  envelope  or  stratum 
produced  during  self-divifiion  is  dissolved,  and  the  conjugating  pairs 
of  fmstules  become  detached  from  the  original  mass ;  they  are  thus 
more  readily  home  away  and  dispersed  in  the  surrounding  currents,  or 
by  the  movements  of  worms  or  insects,  and  their  detection  becomes  in 
consequence  more  casual  and  difficult."  It  is  not  improbable,  however, 
that  the  mode  of  collecting,  and  the  time  that  is  often  suffered  to  elapse 
before  the  collection  is  submitted  to  investigation,  may  have  more  to  do 
iriih  the  fact.  And,  in  c<mffrmation  of  this  view,  I  would  mention 
that,  although  I  have  for  very  many  years  been  engaged  in  the  study 
of  the  DiatomacesB,  and  have  made  innumerable  collections  at  aU 
seasons  of  the  year,  I  have  not  been  so  fortunate  in  obserring  insi»nces 
ci  conjugation  as  some  friends  whose  collections  have  been  made  with 
a  view  to  the  discovery  of  other  organisms.  Their  gatherings  are 
usually  made  in  large  bottles  containing  a  considerable  quantity  of 
water,  by  which  the  specimens  may  be  preserved  for  a  long  time  in 
their  normal  state— ^ny  gatherings  bemg  put  up  in  minute  bottles  with 
little  water,  so  that  the  vigour  of  the  frustules  is  greatly  abated  be- 
fore an  opportunity  of  examining  them  may  be  afforded.  As  to  the 
seasons  of  the  year  in  which  conjugation  is  most  likely  to  occur,  the 
facts  hitherto  accumulated  do  not  i^ord  much  information.  Besides 
the  ease  of  Diatome  vulgare  which  I  observed  in  conjugation  in  the 
month  of  August,  seventy-two  observations,  with  specification  of  date, 
have  been  recorded,  making  seventy-three  in  all.  Of  these,  twenty- 
three  occurred  in  spring,  twenty  in  summer,  twenty-four  in  autumn, 


242  Proceedings  of  the  Mot/al  Irish  Academy. 

and  only  six  in  winter.  The  paucity  of  such  observations  during  the 
winter  may,  however,  he  traceahle  to  the  fact  that  then,  in  conse- 
quence of  the  inclemency  of  the  weather,  fewer  gatherings  are  made, 
than  because  the  process  of  conjugation  is  of  less  frequent  occurrence 
during  the  season. 

ClasHfieatian. 

In  the  various  systems  of  classification,  the  several  authors  have 
treated  the  facts  they  had  to  arrange  as  Procrustes  is  said  to  have  dealt 
with  his  guests  :  **  Qui  ad  lectum  hospites  emensus  breviores  exten- 
debat  longiores  decurtabat."  How  just  this  observation  is  will  be 
obvious  if  we  consider  Pfitzer's  fair  criticisms  on  the  anomalies  of  the 
systems  of  classification  hitherto  propounded.  All  systems  are  arti- 
ficial ;  and  when  we  consider  the  immensity  and  variety  of  Nature's 
productions,  we  cannot  wonder  if  in  every  group  some  organisms  will 
be  found  to  exist  which  cannot,  without  violence,  be  reduced  into  the 
order  proposed.  Every  plan  of  arrangement  will  be  liable  to  objection; 
and  that  may  be  regarded  as  the  best  which  is  the  most  obvious,  the 
most  simple,  the  most  comprehensive,  and  productive  of  the  fewest 
anomalies. 

Pfitzer  considers  that  the  imperfections  of  the  existing  systems  are 
traceable  to  the  fact  that  the  ground-plan  has  been  laid  down  on  a 
single  line,  and  as  a  remedy  suggests  a  system  of  classification  based 
on  several  concurrent  lines,  the  principal  of  which  are  the  character 
and  number  of  the  endochrome-plates,  the  structure  of  the  sporangia, 
and  the  symmetrical  or  unsymmetrical  form  of  the  frustules  in  their 
several  aspects.  Upon  these  lines  Pfitzer  has  skilfully  constructed  a 
most  ingenious  system  of  arrangement;  but  however  great  its  merits  as 
a  philosophical  abstraction,  it  appears  to  me  liable  to  objection  on 
practical  grounds.  The  dislocation  of  analogous  species  chargeable  on 
former  systems,  so  far  from  being  avoided,  is  scarcely,  if  at  all,  di- 
minished by  the  proposed  plan.  Here  we  have  the  Nitzschicae  brought 
into  close  contact  with  the  Naviculeae ;  the  symmetrical  Synedrise  and 
the  unsymmetrical  Eunotiese  are  placed  side  by  side,  and  in  near 
proximity  to  the  Surirelleae.  The  symmetrical  PragilariesB  are  severed 
from  the  symmetrical  SynedrisB,  and  associated  witi  the  unsymmetri- 
cal Meridiese.  The  Tabellariese  are  separated  from  the  FragiLariesB 
and  ranged  with  the  LichmophoresB.  The  character  of  the  endo- 
chrome-plates seems  to  me  a  condition  of  too  recondite  a  nature  to 
admit  of  practical  application ;  besides,  the  induction  of  facts  on  the 
subject  is,  as  yet,  far  too  limited  to  justify  its  adoption.  As  to  the 
reproductive  process  and  its  results,  if  our  knowledge  on  the  subject 
were  sufficiently  comprehensive,  it  would  furnish  most  valuable  help 
towards  the  construction  of  a  satisfactory  arrangement  of  the  DiatcP- 
maceoB ;  but,  unhappily,  in  the  great  dearth  of  authentic  facts  illustra- 
tive of  the  subject,  we  are  not  wairanted  in  using  the  knowledge  we 
have  as  a  ground  plan  of  a  general  systematic  arrangement. 


O'Meaba — R^ort  on  the  Irish  DiatomaeecB,  243 

The  reproductiye  process  has  not  been  observed  in  more  than  about 
SLzty-fiye  species,  and  in  some  of  these  cases  there  is  a  difference  of 
opinion  as  to  the  facts.  A  system,  therefore,  in  which  this  process 
«onstitntes  an  important  part  of  the  ground  plan,  is  practicidlj  ob- 
jectionable, as  founded  on  hypothesis.  - 

The  system  which  appears  to  me  to  have  most  to  recommend  it  is 
that  which  has  been  matured  by  Heiberg,  founded  on  the  symmetri- 
cal or  tmsymmetrical  structure  of  the  frustules  in  their  various  aspects. 
There  are  two  principal  aspects  in  which  a  diatomaceous  frustule  may 
be  regarded — ^the  front  view,  in  which  the  hoop  or  connecting  band  is 
presented  to  the  eye,  and  the  side  view,  in  which  one  or  other  of  the 
two  valves  is  under  observation;  and  in  both  these  positions  the 
longitudinal  and  transverse  axes  are  to  be  considered.  If  in  these  two 
positions,  and  in  these  varied  views,  exact  symmetry  obtains,  the  frus- 
tule is  said  to  be  symmetrical  in  all  its  ftspects ;  but  if  the  two  oppo- 
site valves  are  not  uniform,  or  the  portions  of  the  valves  on  either 
side  of  the  transverse  or  longitudinal  axis,  on  side  view  or  front  view,  do 
not  exhibit  the  same  proportions  or  outline,  the  frustule  is  said  to  be 
unsymmetrical  on  that  view  or  axis  on  wliich  the  difPerence  of  form  is 
observable.  Such  is  the  ground  plan  of  Heiberg's  systematic  arrange- 
ment, and  which  I  have  adopted  in  the  present  report.  It  is  not, 
indeed,  wholly  free  from  the  objections  to  which  other  systems  are 
liable,  and,  possibly,  may  be  open  to  others  peculiarly  its  own ;  but 
£(t01  the  principle  on  which  the  arrangement  is  based  commends  itself 
as  being  at  once  most  simple,  most  comprehensive,  and  most  easily 
applied. 

There  are,  however,  two  very  important  yet  subordinate  features 
of  Heiberg's  system,  in  regard  to  which  I  cannot  adopt  the  views  of 
that  distinguished  author.  He  ranges  the  numerous  Cuneate  species 
as  aberrant  varieties  of  the  families  which  in  other  respects  they  most 
closely  resemble;  for  example,  Meridion  and  Asterionella  are  asso- 
ciated vrith  the  Pragilariese,  under  the  distiQctive  appellation  of 
Pragilarieae  cuneatse ;  Podosphenia  with  the  StriatillesB,  as  Striatillese 
cuneatsB ;  Gomphonema  and  Cocconeis  with  the  Naviculeae,  as  Navi- 
culese  cuneatae ;  whereas  I  have  collected  the  numerous  species  with  a 
cuneate  outline,  under  the  one  general  group  of  Cuneatae.  Again, 
the  numerous  species  of  Diatomaceee,  as  is  well  known,  exhibit  various 
normal  phases  of  growth.  Some  species  are  normally  free,  others 
attached  by  a  short  gelatinous  cushion,  or  a  larger  or  shorter  stipes ; 
the  frustules  in  some  genera  are  simple,  while  in  others,  after  self- 
division,  they  remain  in  concatenate  or  ribbon-like  filaments;  in 
some  genera  the  frustules  are  naked,  while  in  others  they  are  en- 
veloped in  mucous  fronds,  of  which  some  are  indefinite,  others  definite, 
forming  simple  or  composite  tubes.  These  peculiarities  of  growth 
Heiberg  treats  as  of  Httle  significance ;  and  accordingly,  the  genera 
Schizonema,  Berkleya,  and  Colletonema,  the  frustules  of  which  are 
included  in  tubes;  Dickiea,  the  frustules  of  which  are  imbedded  in 
A  less  definite  mucous  mass;  Diadesmis,  the  frustules  of  which  are 


244  Proceedings  of  the  Bot/al  Irish  Academy. 

Tiidted  in  short  filamentB;  and  Brebiflsonia  Boeckei  »  Doryphora 
Boeokeiy  in  which  the  frustules  are  stipitate,  are  notwithstanding 
these  pecnliaritieB  of  growth  included  as  species  under  the  genua 
l^^avionla.  If  Smith  and  others  attached  too  much  value  to  these  sub- 
ordinate features,  and  therefore  separated  the  forms  which  exhibited 
them  very  far  from  the  Nayiculese,  with  which,  as  regaids  the  general 
structure  of  the  frustules,  they  are  intimately  related,  Heiberg,  on 
the  other  hand,  I  consid^,  has  made  a  mistake  in  ignoring  these 
peculiarities  altogether.  Eecognising  these  yarious  normal  modes  of 
growth  as  generic  distinctions,  I  have  included  the  forms  as  separate 
genera  of  the  group  Naviculoce. 

On  the  JDistrihuiion  of  the  Diatomacea, 

Some  species  are  found  only  in  fresh  water,  some  only  in  salt 
water,  while  others  select  as  their  normal  habitat  places  in  which  salt 
and  fresh  water  habitually  or  occasionally  commingle.  I  have 
indeed  frequently  found  rresh  water  species  in  the  stomachs  of 
Ascidians  dredged  from  a  considerable  depth  in  the  sea;  but  their 
occurrence  therein  indicates  the  influx  of  fresh  water  in  the  immediate 
neighbourhood.  And  when  marine  forms  are  found  in  fresh  water,  as 
occasionally  they  may  be,  they  indicate  that  the  place  is  within  the 
range  of  tidal  influence. 

An  experienced  observer  will  be  able  at  a  glance  to  ascertain 
whether  a  gathering  is  marine,  or  made  in  fresh  or  brackish  water ; 
and  not  only  so,  but  will  be  able  to  discriminate  the  lacustrine  and 
alpine  forms  from  those  incidental  to  other  situations. 

It  is  not  possible  to  ascertain  for  what  period  the  life  of  the 
Biatomaceee  continues,  but  when  their  course,  be  it  long  or  short,  is 
ended,  the  silicious  covering  sinks  into  the  sediment:  and  when  in 
the  process  of  ages  the  sediment  is  solidified  into  rock,  the  exuvise  of 
the  Diatoms  that  lived  in  the  water  during  the  period  of  deposition 
continue  unaltered  in  their  stony  shroud.  If  the  rock  be  decomposed 
by  natural  or  artificial  agencies,  they  may  be  extracted,  and  subjected 
to  inspection ;  and  if  found  in  sufficient  number,  the  species  discovered 
may  serve  to  illustrate  the  circumstances  under  which  the  deposit  waa 
formed. 

Irrespective  of  the  variety  and  symmetrical  beauty  of  the  Diato- 
macesB,  there  is  another  circumstance  which  invests  them  with  a  pecu- 
liar interest :  it  is  this,  that  no  existing  organism,  whether  it  be 
vegetable  or  animal,  can  boast  of  so  ancient  a  lineage.  Countless  have 
been  the  genera  and  species  of  living  beings  which  flourished  during 
the  several  geological  periods,  and  of  which  no  representatives  survived 
the  vicissitude  which  brought  their  epoch  to  a  conclusion ;  but  so  far 
back  in  the  annals  of  the  earth  as  research  has  been  able  to  trace  the 
Diatomacese,  the  species  which  have  been  discovered  are  identical  with 
those  we  have  living  at  the  present  time.  Numerous  are  the  fossil  or 
vubf  ossil  diatomaceous  deposits  which  have  been  discovered  in  all  parts 


O'Meara — Iteport  an  the  Irish  Diatomacece. '         245 

of  the  globe;  some  the  acoimmlationB  of  marine,  others  of  frecih 
water  growth.  Among  these  latter,  the  Irish  deposits  of  Lough 
Monme,  Lough  Islaadieavy,  Toombe  Bridge,  and  ToUymore  Park^ 
are  distingaished  for  the  number  and  beauty  of  the  species  they  con- 
tain :  and  we  are  indebted  to  the  industry  and  intelligence  of  Mr. 
Gray,  of  Belfast,  for  the  discorery  of  seveial  sub-peat  collections  in 
▼aiious  parts  of  the  country.  Nearly  all  the  species  contained  in 
tiieseyarious  deposits  have  been  found  Hving  at  the  present  day;  audit 
is  a  noteworthy  fact,  that  the  forms  of  these  numerous  species,  howeyer 
remote  from  one  another  in  time  and  space,  exhibit  no  appreciable 
divergency.  As  an  illustration  I  may  mention  a  few  facts.  Through 
the  kindness  of  Mr.  Kitten,  of  T^orwich,  I  was  supplied  with  a  sample  of 
a  fresh  water  deposit  from  California,  which  contained  numerous  speci- 
mens of  Synedra  amphirhynchus,  in  no  respect  differing  from  the 
specimens  of  the  same  species  I  had  found  living  a  few  days  before, 
in  a  ditch  not  far  from  my  residence  in  the  county  Dublin.  Another 
deposit  discovered  by  Br.  Moss,  R.  N.,  at  Yancouver's  Island,  waa 
sent  to  me  for  examination ;  and  in  it,  among  many  other  well-known 
forms,  I  found  in  great  number,  specimens  of  Navicula  Americana,  in 
all  respects  identical  with  forms  of  that  species  collected  by  my  friend 
the  Bev.  George  Davidson,  from  a  deposit  at  Lough  Canmore,  in  the 
north  of  Scotland,  and  those  I  had  myself  gathered  some  time  ago  in  a 
living  state  on  the  borders  of  Lough  Neagh.  Count  Castracone  ia 
of  opinion  that  Diatoms  must  have  existed  even  in  the  remote  ages  of 
the  PalflBozoic  period.  It  remains  to  be  proved  whether  this  was  so 
or  not ;  but  in  his  researches  in  the  lignite  formation  of  Urbino  he  has 
traced  existing  species  so  far  back  as  the  earlier  epoch  of  the  Tertiary 
formation.  The  specimen  of  lignite  examined  by  this  distinguished 
Italian  naturalist  was  furnished  by  Professor  Mici,  who  considered  it 
to  belong  unquestionably  to  the  Miocene  period.  This  result  is  con- 
firmed by  the  statement  of  Pfitzer,  that  all  the  fresh  water,  as  well  aa 
marine  forms  hitherto  discovered  in  the  deposits  of  the  Tertiary 
period,  belong  to  existing  genera  and  species.  The  generations  of  a 
Diatom  in  the  space  of  a  few  months  far  exceed  in  number  the  genera- 
tions of  man  from  the  earliest  time  to  the  present  day ;  and  yet 
we  find  that  the  individuals  now  living  retain  without  alteration  the 
characteristics  which  distinguished  the  species  at  the  remotest  time  to 
which  their  existence  can  be  traced.  It  might  be  alleged  in  this  case 
that  the  silicious  valves  within  which  the  valves  of  successive  genera- 
tions are  developed  necessarily  impress  the  characters  of  the  parent  on 
the  offspring ;  and  that,  therefore,  any  tendency  to  variation,  however 
powerfully  it  might  operate,  would  be  checked  by  the  irresistible 
force  of  external  pressure.  But  the  sporangia  before  the  soft  skin 
has  become  solidified  by  the  secretion  of  silex  are  of  a  more  plastic 
character,  and  afford  a  facility  for  variation  if  the  cell-contents  were 
endowed  with  any  such  tendency.  And  although  the  formation  of 
sporangia  has  been  observed  in  but  very  few  instances,  yet  the 
frequent  recurrence  of  this  process  of  reproduction  is  forced  on  our 


246  Proceedings  of  the  Boyal  Irish  Academy, 

acceptance  as  a  necessary  inference  from  the  fact  of  the  continuoiu 
existence  of  numerous  species,  despite  of  the  law  which  regulates 
their  multiplication  by  the  process  of  self-division.  As  in  each  suc- 
cessiye  act  of  fission  the  newly-formed  Y£dves  are  smaller  than  those 
within  which  they  have  been  secreted,  the  species  would  soon  become 
€xtincty  were  there  not  a  provision  made  for  its  perpetuation  in 
the  process  of  sporangial  reproduction.  All  the  circumstances  consi- 
dered, I  am  led  to  regard  the  Diatomaceo)  as  a  group  of  organism  on 
which  the  Creator  has  impressed  certain  distinctive  characteristics  from 
which,  through  countless,  successive  ages,  they  have  shown  no  ten- 
dency to  deput. 


LIST   OP   SPECIES. 

A.  Frustuhs  symmetrical.     1.    Valves  circular. 

Family  I.   MELOSIRELaS,  Kiitz. 

Frustules  simple,  or  adhering  in  filaments.     Circular  on  side  view. 


This  family,  since  the  adoption  of  it  by  Kiitzing,  has  undergone 
considerable  modification  in  respect  to  the  genera  included  within 
it.  If  we  omit  the  ill-defined  genus  Pyxidicula,  the  forms  he  em- 
braced within  it,  with  the  exception  of  Cyclotella,  belonged  to  those 
genera  distinguished  by  the  filamentous  character  of  their  growth. 
Kiitzing  recognised  the  analogy  between  these  genera  and  tiiose  of 
which  Coscinodiscus  may  be  regarded  as  the  type,  but  placed  them 
widely  apart,  principally  on  the  ground  of  the  areolatc  striation  of  the 
latter.  This  character,  however,  is  by  no  means  universal,  and  even 
if  it  were,  could  scarcely  justify  so  great  a  dislocation.  Grunow, 
therefore,  who  is  followed  by  Hciberg,  includes  among  the  Melosirea) 
all  the  symmetrical  forms  circular  on  the  side  view,  irrespectively  of 
their  peculiarities  of  striation ;  thus  establishing  a  very  distinct  and 
well-defined  group  which  I  adopt — ^my  only  difficulty  in  doing  so  aris- 
ing from  the  fact  that  in  the  genus  Cyclotella,  some  of  the  included 
species  are  waved  on  the  front  view,  and  for  this  reason  can  scarcely 
be  considered  as  symmetrical  in  all  aspects,  in  the  sense  of  Grunow 
and  Ileiberg. 

Genus  I.  Melosira,  Agardh. 
Frustules  filamentous.     Convex  at  the  ends,  filaments  free. 


Melosira  borrerii,  (Greville.)     Marine  or  brackish  water. 

Valves  sub-hemispherical;  girdlebands  marked  with  conspicuous 
circles  of  cellules;  filaments  varying  in  breadth;  colour  of  the  desic- 
cated filaments,  a  rich  brown.     (PI.  26,  fig.  1.) 


O'Meara — Report  an  the  Irish  Diatomacece.  247 

Greville,  in  Hooker's  Brit.  Flora  *  p.  401.  Vm.  Sm.  B.  D.,  Vol.  ii., 
p.  56;  PL  L.,  fig.  330.  Heiberg,  De  Danske  Diat.,  p.  28.— M.  moni- 
liformis, Kiitz.  Bac,  p.  53,  T.  iii.,  fig.  2.  Raben.  PL  Eur.,  p.  38. 
Rails,  in  Pritch.,  p.  817,  PL  t.,  fig.  71. 

Biyer  Slaney,  near  Killnrin,  Co.  Vezford.  Brackish  ditch  near 
Wexford  town.  Malahide,  Dollymount  strand,  Howth,  Co.  Dublin. 
Sea  weeds.  Giants'  Causeway,  Co.  Antrim.  Brackish  ditch  near  the 
town  of  Wicklow.    R.  Nannywater,  Laytown,  Co.  Meath. 

Mehiira  suhflexilhy  (Kiitz.)    Presh  or  brackish  water. 

Prostules  usually  narrow  elongate,  slightly  inflexed  upon  the 
margin.     (PL  26,  fig.  2.) 

Kiitz.  Bac.,  p.  53,  T.ii.,  fig.  13.  Wm.  Sm.,  B.D.,  YoL  ii.,  p.  57^ 
PL  LI.,  fig.  331.  Heiberg,  Do  Danske  Diat.,  p.  28.  Rab.  PL  Eur.^ 
p.  39. 

Considerable  diversity  of  opinion  exists  as  to  the  habitat  of  thiei 
species.  According  to  Kiitzing  it  belongs  to  the  fresh  water  forms, 
haying  been  found  by  him  in  rapid  brooks.  ''In  schnell  fliessenden 
Bachen."  Bac,  p.  54.  Still  more  precisely  docs  Rabenhorst  assign 
to  it  a  fresh  water  habitat.  "  Hab.  in  rivulis  Sporadice  per  totiun 
Europam  e  planitie  usque  in  regionem  montanam  superiorem,  PI.  Eur., 
p.  39.  Wlule  Smith  giyes  it  either  a  fresh  water  or  brackish  locality, 
Heiberg  makes  it  a  marine  species.  His  remarks  are  worthy  of  notice. 
"Smith  attributes  the  authorship  of  this  species  to  Kiitzing,  but 
Kiitzing's  figure  can  hardly  be  identified  with  certainty,  and  seems  to 
be  more  properly  referrible  to  Melosira  varians.  Kiitzing's  Melosira 
Jurgensii  more  nearly  resembles  Smith's  species,  and  so  Pritchard 
accepts  it.  But  Pritchard  calls  the  species  Melosira  Jurgensii,  and 
represents  Melosira  subflexilis  Sm.  as  a  synonym;  but  in  any  case 
tlus  ought  to  be  reversed,  inasmuch  as  Smith  was  the  first  to  define 
the  species  so  that  it  could  be  identified  with  certainty."  "Smith 
assigns  it  to  fresh  water,  but  as  the  localities  mentioned  are  near  the 
mouths  of  rivers,  the  species  possibly  has  been  borne  out  along  with  the 
floods."  De  Danske  Diat.,  pp.  28,  29.  In  addition,  I  have  only  to  say 
that  the  localities  in  which  the  species  has  been  found  by  mo  in 
Ireland  are  marine,  but  still  liable  to  the  access  of  fresh  water. 

Lough  Poyle,  Bellarena,  Co.  Derry.     Greystones,  Co.  Wicklow. 

Melosira  varians,  (Agardh.)    Presh  water. 

Ends  of  the  frustules  not  so  convex  as  in  the  preceding  species.. 

Kiitz.  Bac,  p.  54,  T.  ii.,  fig.  10.     Rab.  Die  Siissw  Diat.,  p.  13, 

T,  ii.,  fig.  4.    Wm.  Sm.  B.D.,  Vol.  ii.,  p.  57,  PL  li.,  fig.  332.    Ralfs, 


*  For  explanation  of  contxactionB  and  list  of  references,  ride  List  at  end  of  Report. 


248  Praeeedings  of  the  Eoyal  Irish  Academy. 

in  Pritch.,  p.  817,  PI.  xv.,  fig.  32.    Heiberg,  Do  Da&dce  Biat.,  p.  27. — 
ChtUionella  varians,  Ehr.  Inf.  T.  x.,  fig.  4. 

Very  common  in  streams  and  fresh:  springs. 

MeUaira  dtstatu,  (Eutz.)    Fresh  water. 

Frustules  short,  but  slightly  convex  at  the  ends,  distinotly  puno* 
tate.     (PI.  26,  fig.  8.) 

Kiitz.  Bac.,  p.  64,  T.  ii.,  fig.  12.  Rab.  Die  Siissw  Diat.,  p.  13, 
T.  ii.,  fig.  9.  Wm.  Sm.  B.D.,  Vol.  ii.,  p.  68,  Pi.  lxi.,  fig.  385. 
Balfs,  in  Pritch.,  p.  818. — Gallionella  diatans,  Ehr.  Inf.,  p.  170, 
T.  xxi.,  fig.  4. 

Smith  describes  this  species  as  "  obscurely  cellulate,"  and  distin- 
guishes it  on  this  ground  &om  his  Melosira  nivalis,  which  he  charac- 
terises as  '*  distinctly  cellulate,"  but  remarks  that  **  this  chakticter  ia 
probably  insufllcient  to  justify  their  separation."  B.  D.,  Yol.  ii.,  p.  58. 
The  forms  occurring  in  the  Bilin  Polirschiefer,  one  of  the  localities 
assigned  by  Kiitzing  to  Melosira  distans,  are  most  distinctly  punctate; 
I  am  therefore  disposed  to  consider  that  Smith's  species,  Melosira 
nivalis,  cannot  be  sustained. 

Killikee,  Dundrum,  Co.  Dublin.  Kilcool,  Co,  Wicklow.  Pond 
neat  Armagh. 

Genus  II.    LTsiGoarnTX,  Link. 

Frustules  globose  or  cylindrical,  valves  furnished  with  an  elevated 
keel  which  runs  parallel  with  the  sutures ;  in  other  particuliurs  as  in 
Melosira. 


I  have  adopted  this  genus  in  deference  to  the  authority  of  Bfefberg, 
who,  i*eferring  to  Lysigonium  nummuloides,  remarks,  '*  This  species, 
which  by  all  the  more  recent  authors  has  been  assigned  to  the  genus 
Melosira,  in  my  judgment  ought  to  constitute  a  type  of  a  new  genus  to 
whicli  Melosira  westii  Wm.  Stn.,  which  does  not  occur  in  our  country, 
may  also  be  referred.  The  name  liysigonium  was  in  the  first  instance 
applied  by  Link,  to  0.  F.  Muller's  Conferva  moniliformis,  with  which 
in  all  probability  this  species  is  identical ;  and  for  this  reason  it  seems 
most  conreni^it  to  re-establish  ttte  genus  to  receive  it."  De  Danske 
Diat.,  p.  29.  Heiberg  further  remarks,  **  that  the  known  species  form 
ahorter  or  longer  filaments,  attadied  or  free ;"  but  I  have  never  seen 
any  of  the  filaments  attached. 

LffBtgmium  nummuldides,  (Lyngbye,  Kiitz;)    Marine. 
Ordinary  frustules,  globose.     Keel  thin,  in  front  view  appearing  as 
lines  projecting  like  horns.     (PI.  26,  fig.  4.) 

Heiberg,  De  Danske  Diat.>  p.  29. — Melosira  nnmdittloides,  Kiitc. 


O'Meaaa — Beport  on  the  Irish  Diatomacete.  249 

Bao.,  p.  52,  T.  iii.,  fig.  8.  Wm.  8m.,  B.  D.,  Vol.  ii.,  p.  56.  PI.  xlix., 
fig.  339.  Balis,  in  Pritoh.,  p.  816,  PL  v.,  ^g.  64  and  PI.  xi.,  fig.  14. 
TheM  is  cozi8ideFal>le  diflerence  of  opinion  as  to  the  founder  of  thk 
species ;  Smith  assigns  it  to  Kutzing,  Balfs  to  Dillwyn  and  Agardh. 
On  this  subject  fieiberg  says,  '*  As  above  mentioned,  0.  F.  Muller 
was  probably  the  first  to  discover  this  species,  and  describe  it  under 
the  name  of  Conferva  moniliformis,  oi  Btrand<-neoklaoe,  but  that  can- 
not be  ascertained  with  certainty.  The  present  specific  name  is 
attributable  to  Dillwyn,  who  in  1809  described  a  Conferva  nammu- 
loides,  which  Lyngbye  cites  as  a  synonym  under  his  Fragillaria  num- 
muloides.  But  as  meanwhile  there  do  not  appear  to  be  any  original 
specimens  of  Billwyn's  species,  and  his  figures  can  only  be  approxi- 
mately identified,  while  the  numerous  specimens  of  Lyngbye  which 
fltill  exist  are  all  attributable  to  our  species,  it  seems  most  proper  to 
name  Lyngbye  as  the  author."    De  Danske  Diat.,  p.  29. 

Brackish  ditch  near  Wexford,  Malahide,  Dollymount,  JN'orth- 
wall,  Co.  Dublin.  Salt  ditch  near  Wicklow,  and  many  other  places 
too  numerous  to  mention. 

Lyngonkm  TPestii,  (Wm.  Sm.)    Marine. 

Frustules  somewhat  conical,  furnished  with  two  keels,  one  at  the 
sutore,  another  near  the  end,  considerably  thicker  than  the  similar 
atmcture  in  Lys.  nummuloides,  and  not  projecting  upwards  to  the 
flame  extent. 

Melosira  Vestii,  Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  59,  PI.  lii.,  fig.  833. 
Ealfs,  in  Pritch.,  p.  817.     Bab.  PL  Eur.,  p.  38. 

Dollymount,  Oyster  beds,  Howth,  Co.  Dublin.  Near  "Wicklow. 
Stomachs  of  Ascidians,  Eoundstone  Bay,  Co.  Galway. 

Lyiigonium  WtiffhtHf  (O'Heara.)    Marine. 

Pmstules  rounded  at  the  ends,  narrow,  surrounded  by  a  broad 
keel,  which  curving  slightly  outwards  and  upwards,  then  bending  in- 
wards and  downwards  to  the  surface  of  the  valve,  forms  round  it  a 
crown-like  rim.  In  the  front  view  two  nodules  are  observable  in  the 
central  portion  of  the  valve ;  the  frustule  is  perfectly  hyaline,  without 
aculpture  of  any  kind. 

O'Meara,  Q.  J.  M.  8.,  Vol.  ix.,  PI.  xii.,  fig.  3. 

Arran  Islands,  Co.  Gkdwi^. 

Genus  m.    Podosiba,  Ehr. 

Filaments  attached  by  a  distinct  stipes^  and  genezaUy  short,  con- 
fdsting  of  a  few  fmatuks. 


Heiberg  regarda  the  charaoter  <fti  wlneh'  thia  genus  is  founded  as 


2  50  ProceeduKjH  of  tlie  Royal  Liah  Academy. 

''wholly  destitute  of  a  scientific  basis."  De  Danske  Diat.,  p.  27. 
Most  other  authors  have,  however,  decided  in  favour  of  its  validity. 
Smith's  supposition  that  the  apices  of  the  valves  are  destitute  of 
silex,  with  fieiberg  and  Ealf s,  I  consider  is  founded  on  imperfect 
observation. 

Podosira  Montaynei,  (Kiitz.)     Marine. 

Filaments  usually  consisting  of  two  frustules.  Frustules  large,, 
cylindrical,  globose  at  the  ends.     (PI.  26,  fig.  5.) 

Kiitz.  Bac,  52,  T.  xxix.,  fig.  85.  Wm.  Sm.  B.  D.,  Vol.  ii.,  p. 
53,  PL  xlix.,  fig.  326.  Kalfs,  in  Pritch.,  p.  816,  PI.  v.,  fig.  61.  Rab. 
PI.  Eur.,  p.  37. 

Arran  Islands,  Co.  Gkilway. 

Podosira  hormoides,  (Kiitz.)     Montague.     Marine. 

Frustules  small,  compressed.  Valve  with  distinct  umbilicus^ 
obscurely  punctate. 

Smith  and  Kalfs  attribute  the  species  to  Kutzing ;  Heiberg,  and 
Rabenhorst,  Fl.  Eur.,  to  Montagne. 

Kutz.  Bac,  p.  52,  T.  xxviii.,  fig.  6,  and  T.  xxix.,  fig.  84. 
Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  53,  PI.  xlix.,  fig.  327.  RaHs,  in  Pritch., 
p.  815,  PI.  ii.,  fig.  45.  Rab.  Fl.  Eur.,  p.  37. — ^Melosira  hormoides^ 
Heiberg,  De  Danske  Diat.,  p.  29. — ^Podosira  nummuloides,  Ehr. 

Bannow,  Co.  Wexford.  Salt  ditch,  near  Wexford.  Malahide. 
Piles  on  Strand,  Clontarf,  Co,  Dublin. 

Podosira  maculataj  (Wm.  Sm.)     Marine. 

Frustules  globose,  distinctly  punctate ;  puncta  divided  by  radiate 
bands  of  a  deeper  colour,  which  latter  do  not  reach  the  centre. 
Valves  having  a  distinct  umbilicus.     (PL  26,  fig.  6a.) 

Wm.  Sm.,  B.  D.,  VoL  ii.,  p.  54,  PL  xlix.,  fig.  328.  Ralfs,  in 
Pritch.,  p.  815.     Rab.  Fl.  Eur.,  p.  37. 

Sea  weeds,  Bannow.  Salt  ditch,  near  Wexford,  Arran  Islands^ 
Stomachs  of  Ascidians,  Roundstone  Bay,  Co.  Galway. 

Genus  IV.     Obthosiba,  Thwaites. 

Frustules  attached  in  filaments ;  without  stipes,  plane  on  the  side- 
view,  ornamented  with  a  circlet  of  puncta  parallel  with  the  suture;, 
junction  surfaces  spinous. 

The  genus  Orthosira  was  originally  estabUshed  by  Thwaites,  for 
the  purpose  of  distinguishing  the  filamentous  species  with  level  end 
surfaces  from  those  included  in  Melosira,  the  end  surfaces  of  which 
are  more  or  less  arched,  and  thus  defined  it  has  been  adopted  by  most 


O'Meara — Report  on  the  Irish  Diatomacecp,  251 

sacceeding  anthors.  Balfs  and  Babenhorst,  however,  abandoning  the 
generic  distinctiony  have  relegated  the  seyeral  species  of  Orthosira  to 
the  genus  Melosira.  fieiberg,  on  the  contrary,  recognises  the  distinc- 
tion of  Thwaites,  but  includes  the  species  of  Cyclotella  in  the  genus 
Orthosira,  and  establishes  a  new  genus,  Paralia,  to  receive  the  single 
species  Orthosira  marina  (Wm.  Sm.),  on  the  ground  that  the  frustule 
possesses  an  elevated  keel  similar  to  that  which  characterises  the 
genus  Lysigonium.  It  is  a  question,  then,  whether  the  distinction  of 
Thwaites  should  be  recognised,  as  most  authors  since  his  time  have 
done,  or  discarded,  as  Babenhorst  has  considered  it  ought  to  be ;  and 
the  following  observations  of  Ffitzer  seem  to  supply  a  reasonable 
solution.  Having  referred  to  the  original  distinction,  he  adds,  "A 
far  more  important  distinction  exists  in  the  mode  of  developing  Auxo- 
spores.  Although  the  Orthosirsd  in  their  mode  of  growth  agree 
thoroughly  with  Melosira,  have  the  same  structure  of  the  primordial 
cell,  and  the  same  mode  of  cell-division,  they  difPer  in  this  respect, 
that  in  the  process  of  spore-formation  from  a  single  cell,  the  valves  of 
which  are  pushed  away  from  one  another,  the  contents  enveloped  in  a 
mucous  investment  come  out  free,  and  are  then,  without  being  in  con- 
tact with  the  mother-cell,  developedjinto  a  single  Auxospore  in  which 
the  fbrstling  cell  is  so  situated  that  the  plane  of  division  crosses  that  of 
the  mother-cell,  whereas  in  Melosira  it  is  parallel  to  it.  Thwaites 
had  observed  this  feature  in  the  case  of  Orthosira  aurichalcea,  and 
Smith  refers  to  the  peculiarity  as  an  important  generic  distinction. 
But  only  one  species  had  been  observed  in  this  aspect,  and  so  it  was 
questionable  whether  all  the  OrthosirflB  obeyed  the  same  law.  Fr. 
Schmitz  has  succeeded  in  proving  this  in  respect  to  another  species, 
Orthosira  roeseana  (Bab.),  =  0.  spinosa  (Qrev.) "  XJeber  Bau  und 
Entwicklung  der  Bac,  p.  134.  If  then  the  mode  of  developing  Aux- 
ospores  be  regarded,  as  I  consider  it  ought  to  be,  of  importance  as  a 
generic  distinction,  the  conclusion  is  inevitable  that  the  genus  Ortho- 
sira should  not  be  merged  in  Melosira,  as  Ealf  s  and  Babenhorst  have 
treated  it.  And  also,  forasmuch  as  in  those  species  of  Cyclotella  in 
which  the  formation  of  Auxospores  has  been  noticed,  the  daughter-cell 
is  parallel  to  the  mother-cell,  for  this  reason,  as  well  as  on  the  old 
ground  of  distinction,  the  species  of  Cyclotella  should  not  with  Heiberg 
be  included  in  the  genus  Orthosira. 

Orthosira  arenarxaj  (D.  Moore.)    Presh  water. 

Frustules  very  large ;  cell-cavity  sub-spherical.  Spines  on  juncture 
surfaces  short,  broad,  and  close.  StruB,  on  side  view  punctate, 
radiate,  stronger  at  tibe  margin,  and  loosing  their  radiate  arrangement 
as  they  approach  the  centre.  StrisB  on  front  view  punctate,  trans- 
Terse.     (PL  26,  fig.  6.) 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  69,  PL  lii.,  fig.  334.  Heiberg,  D© 
Banske  Diat.,  p.  31.  Balfs,  in  Ann.  N.  Hist.,  Yol.  xii.,  p.  349, 
PI.  ix.,  fig.  4.— Melosira  arenaria,  Kiita.  Bac.,  p.  55,  T.  xxi.,  fig.  27. 
Bab.  Biissw.  Diat.,  p.  14,  T.  ii.,  fig.  6. 

X.  X.  A.  PBGC.,  SBB.  IX.,  VOL.  n.,  sczBirci.  S  If 


252  Proceedings  of  the  JSoyal  IrUh  Academy. 

Besides  the  localities  specified  by  Smithi  name!^,  near  Belfast 
and  Lough  Moume  deppsit,  I  haye  fo^nd  the  species  m  the  following 
places : — ^River  Eme,  Crossdon^,  Go.  CaTan ;  ditich  near  Wezloid ; 
Yemer'arbridge,  Co.  Armagh;  ^lillakee,  Co.  Ihiblin;  stream  near  l[il* 
cool,  Go.  Wicklow;  L.  Keagh,  near  the  town  of  Antrim;  siufaoe  of 
rock  near  Glenarm,  Co.  Antnm. 

Orthosira  aulcaia,  (Ehr.  Eiitz.)    Marine. 

Bpines  of  junction  suifm^es  large,  short,  and  more  distant  than  in 
the  former  species.  Strie  on  side  view  linear,  radiate,  distinct  at  the 
marg^i  attenuated  towards  the  centre,  which  they  do  not  breach; 
puncta  at  the  suture  large ;  stri»  on  front  view  linear,  direct,  parallel 
(PL  26,  fig.  70 

Melosira  sulcata,  Kiitz.  Bac.,  p.  55,  T.  ii.,  fig.  57.  Ealfs,  in 
Pritchu,  p.  819;  PL  ix.,  fig.  131 ;  Plate  xi.,  fig.  26.  Rab.  Fl.  Eur, 
p.  41.— Orthosira  marina,  Wm,  8m.,  B,  D.,  Vol.  ii.,  p.  59;  PL  liiL, 
fig.  838.— dallionella  sulcata,  Ehr. — ^Paralia  marina,  Heiberg,  De 
Danske  Biat.,  p.  33. 

Although  this  species  has  been  described  and  figured  by  Ktitzing 
as  identical  with  Gallionella  sulcata  of  Ehrenberg,  Heiberg  attributes 
it  to  Wm.  Smith.  The  latter  indeed  has  fi^^nred  it  more  perfectly 
than  KUtzing  has  done;  still,  Kiitzing's  figure,  imperfect  as  it  is, 
seems  to  me  unmistakable ;  and  all  uncertainty  as  to  the  species  indi- 
cated is  removed  by  his  reference  to  the  mdunond  deposit  in  which 
the  form  abounds,  for  this  reason  I  have  followed  BaJf s  and  Baben- 
horst  in  assigning  the  specijBs  to  Ehrenberg  and  Kiitzing,  as  well  aa 
restoring  the  original  specific  designation.  And  aa  I  have  not  been 
able  to  trace  any  keel  similar  in  structure  and  position  to  tiiat  of  Lysi- 
gonium,  insteaa  of  adopting  Heiberg's  new  genus,  Paralia,  I  leaye  the 
species  where  Smith  placed  it  in  the  present  genus. 

Cork  and  Kinsale  Harbours,  Wm.  Smith.  Bannow,  Biyer  Slaney, 
Bjllurin,  Go,  Wexford.  Near  Wicklow.  Kalahide.  Dalkey,  Co. 
Dublin. 

OrthosH'a  Dickietif  (Thwaites.)    Fresh  water. 

CeU-cavity  sub-sphericaL  Sutural  puncta  small  and  distant^ 
Spines  on  junction  surfaces  absent.  StnsB,  both  on  front  and  side 
Tiew,  minutely  pimctate.  Puncta  on  front  Tie^f  arranged  in  lines 
parallel  to  the  suture: 

Thwaites,  Ann.  N.  H.,  2  series.  Vol.  i.,  p.  168,  PL  xii.  Wm.  Sm., 
B.  D.,  Vol.  ii.,  pi  60,  PL  lii.,  fig.  335.— Melosira  Didkieii,  Kutz.  Sp.  Alg., 
p.  889.  Ealfs,  in  Pritch;,  p.  820,  PL  xt.,  fig.  29.  Eab.  FL  Eur., 
p.  43. 

This  species  is  remarkable  for  the  abnormal  growth  of  frustule 
within  frustule,  so  fully  described  by  Smith,  B.  D.,  Yol.  ii.,  PL  lii., 
fig.  335.  '  !thwaites  regarded  this  peculiarity  aa  a  mode  of  developing 
aporangia,  while  Smith  considered  it  an  abnormal  development  aiinilar 


O'Kbaba — Mq)ort  <m  the  Irish  DkUomacecB.  263 

to  whAt  he  hiid  noticed  in  Kendion  drcidare  and  ^.  constriotom, 
Himftiitidiqin  BolaiioHi,.  Odontidium'  anomaltun,  and'  Aehhanthes  8ub- 
fleaaflifl..  I.add  fh&'int«resting  deaoriirtion  ^en  by  Pfitzer  ol  an  ano- 
makna  procedure  noticed  by  Fr.  Scbmitz  in  the  deyelopment  ol 
Qrihoaiia  apinoaa,  aa  likelyto  throw  acme  light  on  the  siibj^t.  *'  A 
separation  of  the  finfling«cell  followed,  not  immediatelyy  l>ut«  devia- 
tion occurred  aaalogona- 1<^  what 'h|k8  been  described  in  the  oaae  of 
Waiwiiila  ambigafu  Fint  oae  gbdiebcoid  was  developed,  the  length 
of  which  waA  about  that  of  the  radios  of  the  cell.  This  girdleband, 
according  tp  IV.Ochmitz,  was  attached  only  to  one  valve;  that  which 
ought  to  hAve  been  connected  with  the  other  valve,  if  it'eiiBted  at 
all,  was  only  TudimMitary.  Then,  the  plasm  nxoved  ftbout  only  in  that 
half  of  the  cell  to  which  tho  girdleband  adhered^  and  secreted  a  new 
valve,  which,  aji  m%ht  be  expected,  was  parallel  to  the  original  one 
destitute  of  the  gircUeband^  In  the  cell  so  originating,  division  then 
took  place  in  the  normal  manner,  only  that  the  one  end-cell  of  the  fila- 
ment in  course  of  formation^  instead  of  two  valves  possessed  three. 
Inasmuch  as  a  small  portion  of  the  plasm  remained  behind,  between 
the  two  parallel  valves,  and  then  died  off,  Fr.  Schmitz  was  inclined 
to  think  the  procedure  was  an  abortive  attempt  at  self-division,  one 
portion  of  the  plasm  being  too  small  to  develop  itself  into  a  daughter- 
celL"    Ueber  £aii  mid  Entwicklung  der  Bac,  p.  135. 

Bitch  on  bank  of  Boyal  Canal,  near  Kilcock,  Co.  Kildare.  It  is 
likely  this  species  is  more  common  than  it  appears  from  the  few  lo- 
calities assigned  to  it,  as  in  its  normal  condition  it  may  be  easily  con- 
fonnded  witii  Kelosira  varians. 

Otihotira  oricWcea,  ( Wm.  Sm. )    Freshwater. 

The  cijpole  of  punetathat  in  most  of  the  species. of  this  genus  nms 
pazallel  with  the  suture  is  not  observable  ih  this.  Spines  on  jimction 
surfaced  duttaiict';  valve  not  striated  on  the  side  view,  except  on 'the 
mai^,  where  the  points  of  the  spines  appear  as  small  puncta.  Frus- 
tules  striated' on  froni  view.  StriJee  fine,  punctate,  parallel.'  (Fl/  36, 
fig.«.) 

Balfls  and  S«benh<Mr«t  have  ref eired  this  species  to  Mettens  on  the 
authority  of  Kdtzing,  who  has  figtlred  and  described  a  form  tuider  this 
speeifie  designation.  The  figtire  of  Melosira  orichalcea,  Bac.,  T.  ii., 
fig.  14,  is  by  no  means  defiiute,  and  one  featute  in  the  description 
suggests  the  impression  that  he  had  ^uite  a  different  species  in  view. 
''  8ub  epidermide  silieea  leviter  bis  contractis;"  Bac.  p.  !54,  may  pos- 
sibly refer  to  Orthosim  spinosa,  btit  not  to  Orthosira  brichaloea,  as 
i[gnraA  |)v  fimjfii^  ^  whADBL  BMiprtrc  ^^»>«^**  the  Q^^cies  should  be 
sttabatedi  as  he  was  the  first  t0  give  a  description  and  figure  by 
whioh  it  could  be  satisfactcnily  identified.  Heiberg  makes  tiie  follow- 
ing shrewd  observation  under  Orthpsira  orichalcea : — "  The^  figure  by 
which  Smith  describes  the  process  of  conlugation  in  the  species  under 
consideration,  and  which  he  copied  from  Thwaites'  original  delineation, 

2L2 


254  jProceedings  qf  the  Jtoyal  Irish  Academy. 

deviates  so  mncli  from  the  nonnal  appearance  of  the  species,  that  one 
may  almost  take  it  for  certain  that  it  represents  a  yery  different  form, 
for  a  difference  of  so  much  importance  could  scarcely  hare  aiisen  from 
inadyertence." — ^De  Danske  Diat.,  p.  31.  In  Thwaites'  original 
description  of  Anlocoseira  crenulata,  Kiitz.  ^Melosira  orichalcea,  Ealfs 
(and  Orthosira  orichalcea,  Wm.  Sm.)>  both  the  generic  definition  and 
the  figure  are  inapplicable  to  the  present  species  as  figured  by  Smith. 
*' Aulaeoseira  ceUulis  cylindricis,  hisukatia^  extremitatibus  plus  minusyo 
rotundatis,  in  filamenta  concatenatis."  Ann.  of  T^at.  Hist.  March, 
1848,  p.  7,  most  correctly  describes  Orthosira  Boeseana,  Bab. »  O. 
spinosa  (Wm.  Sm.).  The  frustules,  as  described  ib.  PI.  xi.,  B.,  figs. 
1,  2,  and  3,  are  greatly  more  like  that  form  than  any  other  species, 
and  the  side  yiew,  as  represented  in  the  sporangial  frustule,  is  pre- 
cisely as  the  side  yiew  of  that  species  is  described  by  Smith,  B.  D., 
Vol.  ii.,  p.  62,  PI.  bd.,  fig.  386.  I  am  therefore  diq^osed  to  think 
that  it  was  not  Orthosira  orichalcea,  but  Orthosira  Boeseana,  which 
Thwaites  obseryed  in  the  process  of  forming  sporangia,  or,  as  Pfitzer 
designates  them,  Auxospores. 

Smith's  Irish  localities  are — Well  at  Seven  Churches;  Clonmac- 
noise;  Moanarone,  County  Cork;  Lough  Moume  deposit;  to  which  I 
have  to  add  the  following  : — Biver  Erne,  Crossdoney,  County  Cavan ; 
Lough  Islandreavy,  County  Down ;  Lough  Neagh,  near  the  town  of 
Lurgan,  County  Armagh ;  Killakee  and  Glcnchree,  County  Dublin. 

Orthosira  punctata^  ("Wm.  Sm.)    Fresh  water. 

This  species  is  distinguished  from  the  preceding  chiefly  by  the  i&ct 
that  in  this  the  puncta  are  very  much  larger,  and  ^  more  regularly 
arranged ;  they  are  parallel  to  the  suture,  and  so  regularly  placed  that 
they  sometimes  appear  to  run  spirally.  Heiberg  remarks  that  **  Smith's 
species  is  easily  recognised  by  the  obvious  rows  of  puncta  crossing  one 
another,  which  run  in  oblique  spirals  from  the  suture  up  to  and  over 
the  side  view." — ^De  Danske  Diat.  p.  31.  These  last  words  seem  to 
imply  that  the  side  view  is  punctate  like  the  front  view ;  if  so,  then 
the  species  must  be  regarded  as  certainly  distinct  from  the  preceding. 
Smith  does  not  figure  the  side  view,  and,  in  consequence  of  the  length 
of  the  frustule,  it  is  difficult  to  turn  it  over  so  as  to  get  it  under 
observation.  In  one  case  only  could  I  get  a  view  of  it,  and  then  only 
obliquely ;  in  this  aspect  it  appeared  strongly  punctate.  The  circle  of 
spines  at  the  suture  is  absent  in  this  species  as  in  the  last. 

Balfs,  in  Pritchard,  p.  820,  makes  this  species  synonymous  with 
Melosira  granulata  *>  GaJHionella  granulata,  'Ebr.  and  Babenhorst,  Fl. 
Eur.,  p.  43,  adopts  the  same  course ;  but  so  much  uncertainty  charac- 
terises Ehrenberg's  figures  of  that  species,  I  prefer,  with  Heiberg,  to 
adopt  the  precise  figure  of  Smith,  and  attribute  the  species  to  him. 

TTlster  Canal,  near  Poyntzpass.  Lough  Neagh,  near  Lurgan,  County 
Armagh. 


O'Meaba— £^r^  on  the  Irish  Diatofnae€(B.  255 

Orthosira  Itoe9eana,  (Rab.)    Fjresh  water. 

Inner  surface  of  cell  sub-i^lierical ;  fmstole  milcate  on  either  dde 
of  Bntnre ;  spines  at  the  junction  surfaces  yeiy  distinct  and  long ;  cir- 
clet of  puncta  parallel  with  suture  absent.  Stria  on  side  view  radiate, 
distinct,  with  three  large  puncta  placed  triangularly  at  the  centre. 
On  front  view  stri»  finely  punctate,  and  parallel  with  suture. 
(PI.  26,  fig.  9.) 

Smith,  in  1856,  describes  this  species  as  new,  under  the  name  of 
Orthosira  spinosa.  "Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  62,  PL  bdi.,  fig. 
386.  But  it  had  been  already  described  by  Eabenhorst,  Siissw.  Diat., 
p.  13,  T.Z.,  fig.  5,  in  1853,  as  Ifelosira  Boeseana,  and  with  sufficient 
accuracy,  both  as  respects  ^e  figure  and  the  description,  as  to  render 
identification  certain.  Melosira  Boeseana,  Balfs,  in  Pritch.,  p.  818, 
PI.  v.,  fig.  67. 

Xillakee,  County  Dublin.  Ulster  Canal,  near  Poyntzpass.  Lough 
Keagh,  near  Lurgan,  County  Armagh.  Ditch  at  side  of  Boyal  Canal, 
near  Kilcock,  County  Eildare. 

Genus  V.     Cyclotella,  Kiitz. 

Frustnles  normally  single,  narrow ;  sometimes  slightly  wared  on 
the  front  view ;  on  the  side  view  having  the  valves  more  or  less  dis- 
tinctly divided  into  two  concentric  portions. 


It  is  extremely  difficult  to  define  this  genus  by  words  so  precisely  as 
to  distinguish  it  with  certainty  from  others  nearly  allied ;  yet  still 
the  forms  included  within  it  constitute  a  tolerably  distinct  group.  So 
much  so,  that  almost  all  authors  have  agreed  to  mark  their  peculiarity 
by  a  distictive  generic  name. 

fieiberg  and  Cleve  have  included  the  several  species  under  the 
genus  Orthosira,  with  which  they  are  closely  allied ;  but  I  consider 
them  entitled  to  stand  by  themselves,  not  only  on  account  of  their 
different  modes  of  growth,  but  also  on  account  of  the  distinctive  cha- 
racters of  their  sporangia. 

It  would  appear  at  first  view  that  the  generic  name  Discoplea 
should,  on  account  of  its  priority,  be  preferred  to  the  more  recent  name 
of  Cyclotella.  As  Ehrenberg  has  given  no  verbal  diagnosis  of  his  genua 
Discoplea,  we  have  no  means  of  ascertaining  its  characteristics,  other- 
wise than  by  the  figures,  and  in  these  no  sufficiently  distinctive  feature 
is  discernible.  Not  only  are  forms  that  seem  to  belong  to  different 
species  included  under  the  same  specific  name,  but  more  than  this, 
epecies  belonging  to  Orthosira,  on  tiie  one  hand,  and  more  closely  re- 
aembling  Coscinodiscus,  on  the  other,  are  included  in  the  genus  Disco- 
plea. Kiitzing's  diagnosis  of  his  genus  Cyclotella,  although  sufficient 
to  distingush  it  from  Orthosira,  on  the  one  hand,  is  not  clear  enough,  so 
far  as  words  are  concerned,  to  prevent  confusion  with  Coscinodiscus, 


256  Proceedings  of  the  Royal  Irish  Academy. 

on  the  other.  Yet  his  figures,  however  obscure  in  minute  details  of 
structure,  distinctly  mark  the  separation  of  the  yalyes  into  two  well* 
defined  concentric  parts. 

Walker- Amott  confounded  the  distinction  between  this  genus 
and  Orthosira,  when  he  identified  Gyolotella  dallasiana  with  the  Cydo- 
tella  radiata  of  BrightWell,  which  should  rather  be  indud^  in  Or- 
thosira.  There  is  great  confusion  as  to  the  synonomy  of  the  several 
species;  nor  is  this  surprising,  as  the  eailier  descriptions  and  figures 
are  by  no  means  satisfactory;  and,  in  order  to  avoid  consequent  per- 
plexity, I  consider  there  is  no  more  satisfactory  plan  than  to  follow 
the  line  marked  out  by  the  figures  of  Wm.  Smith,  which  are  so  distinct 
as  to  be  easily  recognised. 

CycloteUa  Kiihingiana,  (Thwaites.)    Fresh  water. 

Frustules  undulate ;  striae  delicate,  marginal,  scarcely  one  half  of 
the  radius  in  length ;  Uie  central  portion  of  the  valve  unstriate.  (PL 
26,  fig.  10.) 

Smith  attributes  this  species  to  fresh  or  brackish  water,  and  with 
this  opinion  Eabcnhorst  concurs.  Walker-Amott  alleges  he  has 
never  seen  the  true  species  from  fresh  water.  Cleve  makes  it  an 
essentially  brackish  water  species,  and  Hciberg  on  the  contrary,  a 
fresh  water  fotm.  This  difference  of  opinion  may  arise  from  mistake 
as  to  identity ;  but  speaking  of  the  form  described  by  Smith  as  C. 
Kiitzingiaua,  I  have  to  say  that  though  I  have  sometimes  found  it  in 
water  slightly  brackish,  it  has  been  commonly  discovered  by  me  in 
localities  far  remote  from  marine  influences,  so  that  I  think  it  is  to  be 
considered  an  essentially  fresh  water  species. 

The  slightly  undulate  outline  which  this  species  presents  on  the 
front  view  may  possibly^  arise  from  the  sinking  in  of  the  valve  in  the 
centre,  and  the  consequent  projection  of  the  outline  of  the  dip  upon 
tho  plane  of  observation.  Thus  Wm.  Smith  accounts  for  the  ap- 
pearance, and  his  opinion  on  the  subject  ^is  supported  by  that  of 
Heiberg. 

Wm.  Sm.,  B.D.,  Vol.  i.,  p.  27,  PI.  v.,  fig.  47.  Raben.  Fl.  Eur., 
p.  82. — Orthosira  Kiitzingiana,  Heib.  De  I)anske  Diat.,  p.  81. 

Stream,  Crossdoney,  Co.  Cavan.  Stream  near  Lame,  Co.  Antrim. 
Tacumshane,  Co.  Wexford.  Ditch  on  banks  of  Eiver  lifEey,  Co. 
Eildare,  near  Ballymore  Eustace.  Tarbert,  Co.  Kerry.  Ditch,  Kil- 
cool,  Co.  Wicklow. 

CyehUila  Meneghinuma^  (Kiitz.)    Fresh  water. 

Frustules  not  undulate  on  the  front  view ;  stris  on  the  valvoa 
much  coarser  than  in  the  former  species,  more  distant,  and  oomndcr- 
ably  longer.     (PI.  26,  fig.  11.) 

Walker-Amott  regards  this  species  as  identical  with  C.  reotangula, 
De  Br^b,  and  the  ^eater  wei^t  attaches  to  his  opinion  as  it  waa 
adopted  after  exammation  of  qiecimens  ^'from  De  Br^bisson  himself 


OlfEARA — Iteport  on  the  Irish  I>iatofnaeecB.  257 

md  a  iMMPtion  of  th'e  only  gathering  lie  ^rer  tnade  of  it  (near  Paris.)" 
Q.  J.  M.  S.,  Oct.,  1860,  p.  245.  Subseqnently  D^  Br^bisson  found  the 
same  form  at  Falaiee,  and  gave  a  figure  of  it  IrMch  is  confirmatoiy  of 
the  opinion  of  Walker- Amott.  ^'  Kotes  on  some  French  Diatomace®," 
Journal  of  Queckett  Mic.  Cluh  for  April,  1870,  fig.  6.  Kiitzing  states 
thalt  this  species  is  adnate.    I  have  never  seen  it  sq. 

Kiitz.  Bac,  p.  60,  T.  xxx.,  fig.  68.  Eiab.  Sussw.  Diat.,  p.  11. 
T.  ii.,  fig.  2.  Possibly  this  specif  may  be  identical  with  C.  Kiitzin- 
giana,  var.  B.  "Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  27 ;  and  if  so,  it  is  not  the 
same  that  Ealfs  has  figured  as  €.  Irectangiila  (Be  Brdb.>  Ealfs,  in 
Fritch.,  PI.  v.,  fig.  54 ;  the  latter  being  Undulate  on  the  iront  view, 
whereas  the  present  species  is  rectangular. 

Lncan.    Feather-bed  mountain,  Go.  Dublin.    Kilcool,  Co.Wicklow. 

CffchteUa  opereidata,  (Kiitz.)    Fresh  water. 

Marginal  stri®  short,  fine,  linear;  central  part  of  valve  covered 
with  distinct  moniliform  strice  radiately  arranged.     (PI.  26,  fig.  12.) 

Though  Smith,  who  is  followed  by  Ealfs,  describes  the  striae  in 
this  species  as  obscure  and  very  short,  the  figure  in  both  oases  is  too 
clear  to  admit  of  any  doubt  as  to  identification. 

Kiitz.  Bac,  p.  50,  T.  i.,  figs.  1,  12,  and  15.  Vm.  Sm.,  B,D., 
Vol.  i.,  H.  v.,  fig.  48.  Raffs,  in  Pritch.,  p.  811,  PI.  v.,  fig.  53.— 
Orthosira  operculata,  Heiberg,  De  Danske  Diat.,  p.  32.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  217.  Thid  form  is  not  identical,  with 
that  described  by  Walker- Amott  under  this  name,  with  the  centre 
destitute  of  stri«,  but  probably  is  the  same  as  the  variety  he  identifies 
with  C.  minutula,  Kiitz.  See  Amott  on  Cyclotella,  Q.  J.  M.  S.  for 
Oct.,  1860,  pp.  246,  247. 

Lower  Lake,  Killamey,  Co.  Kerry.  Derrylane  Lake,  Co.  Cavan. 
Glenchree,  Co.  "Wicklow.  River  Bann,  near  Coleraine,  Co.  Deny. 
River  Erne,  Crossdoney,  Co.  Cavan.  Royal  Canal,  Enfield,  Co.  Meath. 
Lough  Keagh,  near  Lurgan,  Co.  Armdgh.  Lough  Moume  deposit. 
Lough  Island-Reavy  deposit,  found  also  living  in  the  same  place. 

CydoUlla  operculata^  var.    Fresli  water. 

Margin  of  valve  fringed  with  short  rounded  distinct  costs,  oyer 
which  there  is  a  circle  of  very  fine  linear  striae,  short ;  centre  of  the 
valve  as  in  the  former,  but  the  moniliform  striae  much  finer  and  more 
obscure.    (PI.  26,  fig.  12,  b.) 

On  banks  of  the  Liffey,  near  Ballymore  Eustace,  Co.  Kildare. 
Lough  Neagh,  near  Lurgan,  Co.  Armagh. 

Cyclotella  antiqua,  fWm.  Sm.)    Fresh  water. 

Marginal  portion  of  the  valve  narrow,  marked  with  short,  broad, 
triangularly  formed  bars,  over  which  thei'fe  is  a  circlet  of  very  fine 
short  linear  striae ;  central  portion  occupied  by  about  nine  triangular 
bars  which  do  not  reach  the  centre.     (PI.  26,  fig.  13.) 


258  Proceedings  of  the  Royal  IriA  Academy. 

Smith  does  not  figure  the  fine  marginal  striae,  and  describes  the 
marginal  triangular  bars  as  if  they  were  monilif orm ;  but  with  this 
exception  his  figure  is  in  every  respect  accurate,  so  as  to  remove  all 
doubt  as  to  the  identity  of  the  species.  Walker- Amott  considers  that 
Smith's  form  is  identical  with  C.  minutula,  Kiitz.,  found  by  him  in 
the  Liineburg  deposit,  and  adds,  ''It  is  this  which  Smith  obtained 
from  the  Lough  Moume  deposit,  but  which  he  has  unfortunately 
referred  to  C.  anti^ua,  a  species  which  does  not  occur  in  any  of  the 
Irish  deposits  which  I  have  examined."  On  Cyclotella,  Q.  J.  M.  S., 
Oct.,  1860,  p.  246.  The  forms  of  Cyclotella  found  on  the  only  slide 
I  possess  £rom  the  Liineburg  deposit  are  those  of  C.  operculata. 
Walker-Amott  evidently  had  not  seen  any  specimen  of  C.  antiqua, 
for  the  distinctiveness  of  the  q>ecies  is  too  obvious  to  have  escaped  hia 
keen  observation,  had  even  a  single  form  of  it  come  under  his  notice. 

Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  28 ;  PI.  v.,  fig.  49.  Ralfs,  in  Pritch., 
p.  812.     Rab.  Fl.  Eur.,  p.  33. 

Lough  Moume  deposit,  in  which  I  have  occasionally  noticed  it. 
Sub-peat  deposit,  Dromore,  Strangford  Peat,  Co.  Down. 

Cyclotella  rotula^  (Eiitz.)    Fresh  water. 

Valve  with  a  sHght  depression  towards  the  centre,  strisB  radiate, 
running  from  the  margin  to  the  centre ;  coarse  at  the  margin,  finer 
and  finer  as  they  approach  the  centre,  where  they  appear  confused. 
StrisB  linear,  but  notched,  so  as  to  seem  moniliform.  (PI.  26, 
fig.  14.) 

In  consequence  of  supposing  that  Discoplea  rotula  of  Ehr.,  Mic, 
T.  XXXV.  A.  xxii.,  fig.  67,  was  a  species  of  Cyclotella,  Kiitzing,  in  his 
Species  Algarum,  changed  his  original  specific  name  to  that  of  Cyclo- 
tella astrtea,  and  this  nomenclature  has  been  adopted  by  Ealfs  and 
Rabenhorst.  It  is  not,  however,  certain  that  Ehrenberg's  form  pro- 
perly belongs  to  Cyclotella,  and  therefore  the  original  name  ought  to 
be  retained. 

Kutz.  Bac,  p.  50,  T.  ii.,  fig.  4.  W.  Sm.,  B.  D.,  Vol.  i.  p.  28  ; 
PI.  v.,  fig.  50.  Walker-Amott,  Q.  J.  M.  S.,  Oct.,  1860,  p.  247.— Cy- 
clotella astraea,  Ealfs,  in  Pritch.,  p.  812.  Rab.  Fl.  Eur.,  p.  34. — Or- 
thosira  rotula,  Heiberg,  De  Danske  Diat.,  p.  32.  Cleve,  Om  Svenska 
och  Norska,  Diat.,  p.  217. 

Lough  Neagh,  in  several  parts.  Lucan,  Feather-bed  mountain, 
and  Grand  Canal,  Co.  Dublin.  River  Bann,  near  Coleraine,  Co.  Deny. 
Lough  Moume  and  Lough  Island-Reavey  deposits.  Small  iorma  of 
this  species  may  be,  at  first  view,  readily  mistaken  for  Cyclotella  oper- 
culata, but  on  close  inspection  the  difference  will  be  obvious. 

Cyehtdla  papulosa,  (N.  S.)    Freshwater. 

Marginal  strisB  of  the  valve  linear,  very  fine,  central  portions 
unstriate  and  occupied  by  a  circlet  of  papillae,  usually  five  or  six  in 
number.     (PL  26,  fig.  15.) 


O'Meara — BepoH  ofi  the  Irish  Diatomacem.  259 

There  is  a  f onn  resemblmg  the  present,  described  by  Ehrenberg  as 
Dificoplea  atmospherica,  from  Nepal,  Mic,  T.  txxi'L  y.,  fig.  4 ;  and 
^Jbo  from  Fayoom,  Egypt,  Hie,  T.  zxxii.  i.,  fig.  3 ;  bnt  as  the  figures 
of  Discoplea  atmospherica  differ  so  widely  from  one  another,  even  if 
there  were  no  doubt  as  to  the  identity,  a  different  name  is  needful  to 
mark  the  peculiarity  of  the  present  species. 

Lough  Neagh,  near  Lurgan,  Co.  Armagh.  Lough  Mask,  near 
Tonrmakeady,  Co.  Mayo.  There  is  a  form  occurring  in  the  Lough 
Moume  deposit,  which  may  be  the  same  as  this,  but  the  papillsQ  are 
usually  injured,  and,  judging  from  the  traces  that  remain,  they  seem 
to  hare  been  more  numerous,  more  slender,  and  more  scattered  than  in 
the  living  forms. 

CydoUUa  Scotiea,  (Eiitz.)    Marine. 

Valve  very  small,  finely  striate  on  the  margin;  the  centre  unstriate. 
Kutz. 

Bac.,  p.  60,  T.  i.,  figs.  2  and  3.  Ealfs,  in  Pritch.,  p.  811.  PI. 
xiv.,  fig.  17.    (PI.  26,  fig.  16.) 

On  sea^ weeds  at  the  (Hants'  Causeway,  Co.  Antrim.  Xiitzing  and 
Balfs  describe  this  species  as  adnate,  but  as  my  specimens  had  been 
treated  with  acid  before  observation,  I  cannot  confirm  this  character. 

CydoteUa  dalkuianay  (W.  Sm.)     Marine. 

Margin  of  the  valve  coarsely  striate;  central  part  rugose,  as  if  blis- 
tered. Smith  represents  the  central  part  as  **  cellulate ;"  but  "Walker- 
Amott  has  more  accurately  described  it  as  ''puckered,  or  as  if  blis- 
tered." 

Wm.'Sm.,  B.  D.,  Vol.  ii.,  p.  87.  Walker-Amott,  Q.  J.  M.  S,  Oct., 
1860,  p.  245.     Kalfs,  in  Pritch.,  p.  813.     Bab.  Fl.  Eur.,  p.  33. 

Stomachs  of  Ascidians.     Boundstone  Bay,  Co.  Galway. 

CffcloteUa punctata,  (Wm.  Sm,)    Freshwater. 

Frustules  undulate  on  front  view;  on  side  view,  striae  close,  radiate, 
very  finely  punctate,  puncta  smaller  towards  the  margin,  which  latter 
is  surrounded  by  a  circlet  of  short,  fine  costae.     (PI.  26,  fig.  17.) 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  87.  Balfs,  in  Pritch.,  p.  813.  PI.  viii., 
fig.  13.    Bab.  Fl.  Eur.,  p.  33. 

Lough  Island-Beavey,  Co.  Down.    Float  bog,  Co.  Westmeath. 

Genus  VI.    Coscinodiscus,  Ehr. 

Frustules  simple,  free,  lenticular;  valve  generally  uniformly  striate. 
Striae  areolate  or  moniliform.    Without  processes  or  undulations. 


Kiitzing  noticed  the  close  affinity  between  Melosira  and  the  pre- 
sent genus,  but  in  his  classification  placed  them  very  widely  apart, 


260  Proceeding$  of  the  Bayal  Irish  Academy. 

simply  because  in  the  latter  the  striation  wais,  as  he  describes  it,  areo- 
late.  3at  subsequent  writers  found  rJiis  distinction  untenable,  inas- 
much as  in  Creswelliay  connected  with  Melosira  by  the  fllamehtoua 
character  of  its  fnistules,  the  striation  is  distinctly  areolate,  while  in 
some  of  the  species  which  are  properly  included  in  the  genus  Goscino- 
discus  the  areolate  character  disappears. 

Heiberg  is  dissatisfied  with  the  diagnoses  which  preceding  authors 
have  given,  but  in  consequence  of  the  limited  amount  of  material  for 
observation  at  his  command,  declines  to  attempt  a  more  satisfactory 
definition.  It  appears  to  me  that  if  Ooscinodiscus  ezcentricus,  which  is 
described  as  havmg  a  spinous  or  dentate  margin,  be  excluded,  we 
shall  then  have  a  tolerably  well-marked  group,  as  above  defined. 


(a)  Dish  with  a  central  rosette. 

Coseinodiseus  oeulus  iridis^  (Ehr.)    Marine. 

Central  rosette,  consisting  of  from  six  to  nine  large  oblong  cellules. 
Cellules  large,  hexagonal,  radiate,  distinctly  smaller  as  they  approach 
the  margin.     (PL  26,  fig.  18.) 

Ehr.  Mic,  T.  xviii.,  fig.  49.  Ralfs,  in  Pritch.,  p.  828.  Raben. 
Fl.  Eur.,  p.  34.  Heiberg,  De  Banske  Diat.,  p.  35.  Cleve,  Om  Svenska 
och  Norska  Diat.,  p.  217. 

Tide  pool,  Monkstown;  on  sea- weeds,  Ballybrack;  tide  pool, 
Dalkey ;  Oyster-shells,  Dublin  Bay,  all  in  the  County  Dublin. 

Coseinodiseus  centralis,  (Ehr.)    Marine. 

Central  rosette  consisting  of  about  eight  large  rounded  cellules 
surroimding  a  single  central  one.  Cellules  distinctly  hexagonal, 
radiate,  nearly  equal,  and  smaller  than  in  the  former  species.     (PI.  26, 

fig.  19.) 

Ehr.  Mic,  T.  xviii.,  fig.  39.  Greg.  Diat.  of  Clyde,  p.  26,  PI.  xi., 
fig.  49.  Balfs,  in  Pritch.,  p.  828.  If  Gregory  describes  and  figures 
with  accuracy  the  form  so  named,  and  found  by  him  in  Glenshira 
Sand,  as  well  as  in  the  Clyde,  it  can  scarcely  be  identical  with  the  pre- 
sent  species.  The  only  d^erenoe,  however,  is  in  the  character  of  the 
cellules  forming  the  central  rosette,  which,  in  his  form,  consiBts  of 
"  three  large  oblong  cells  meeting  in  a  point,  and  between  these,  a 
little  farther  from  the  centre,  tlu'ee  more  cells,  a  little  smaller." 
Balfs,  however,  as  above  cited,  describes  this  portion  of  the  valve  aa 
consisting  of  ''a  few  oblong  cellules,  round  a  circular  one;"  which 
description  accurately  represents  the  appearance  of  the  rosette  in  the 
present  form,  and  therefore  I  adopt  the  specific  namie. 

On  sea-weeds,  Ballybrack,  Dalkey,  Co.  Dublin.  Stomachs  of  Asci- 
dians,  Belfast  Lough. 


O'MsASA — Bq>ort  an  the  Irish  DiatomacecB.  261 

Coicinodisem  Hellaru,  TBoper.)    Marine. 

Cemtfal  rosette,  conflbtmg  of  five  or  six  long  and  narrow  cellules ; 
striffi  extremely  minnte,  punctate,  radiate. 

Eoper,  Q.  J.  M,  B.,  Vol.  vi.,  p.  21,  PI.  iii.,  %  3.  Half s,  in  Pritch., 
828,  PI.  v.,  fig.  63. 

Oyster*  Shelb,  Dublin  Bay. 

Co$em&dfseu»  conetnnus,  (Wm.  Sm.)    Marine. 

Centred  rosette,  consisting  of  from  three  to  eight  large  flattened 
cellules.  Cellules  small,  radiate ;  yalve  diyided  into  computments  by 
radiating  lines,  which  do  not  reach  the  margin. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  84.  Koper,  Q.  J.  M.  S.,  Vol.  vi.,  p.  20, 
PL  iii.,  fig.  12.  Balfs,  in  Pritch.,  p.  828.  Eoper,  as  above  cited,  states  that 
**  the  larger  specimens  show  plainly  a  point  that  is  not  easily  discernible 
in  those  under  '004''  in.  diameter,  namely  a  submarginal  row  of  minute 
spineSy  varying  from  rsWth  to  Wtnrth  of  an  inch  apart,  according 
to  the  si^e  of  the  disk,  anii  from  each  of  which  there  is  a  radiating 
line  almost  to  the  centre  of  the  valve.''  I  have,  in  consequence,  con- 
siderable hesitation  in  including  the  species  under  the  genus  Coscino- 
discus ;  but,  as  the  specimens  that  came  under  my  notice  were  few  in 
numbeor,  and  in  every  case  imperfect,  I  would  not  presume  to  make 
any  change  in  the  position  to  which  it  has  been  assigned. 

It  was  found  by  Wm,  Sm.  in  Einsale  Bay,  and  fragments  have 
occurred  on  sea-weed^,  Ballybrack,  and  on  oyster-shells  from  Dublin 
Bay,  both  in  the  County  Dublin. 

(b).  IHtk  with  a  central  hff aline  epaoe  like  a  perforation. 

Coeemodisoue  perforatU9y  (Ehr.)    Marine. 

Hyaline  centre,  small,  surrounded  by  about  five  rounded  cellules. 
Cellules  large,  indistinctly  hexagonal,  radiate,  decreasing  in  size  near 
the  margin.     (Pi.  26,  fig  20.) 

Smith  describes  the  cellules  as  "  equal,"  and  Ralfs  as  '*  minute  ;'* 
but  in  iny  specimens  they  differ  as  stated  above. 

Ehr.  Mic,  T.  xviii.,  fig.  46.  Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  85. 
Balfs,  in  Pritch.,  p.  829. 

From  stomachs  of  Howth  Oysters,  Tide-pool,  Monkstown,  Dalkey, 
Ballybrack ;  on  Oyster  shells,  Dublin  Bay.  Stomachs  of  Ascidians,. 
Belfast  Bay. 

(c).  Disk  without  a  central  rosette  or  vacant  space.     Cellules  radiate. 

Coseinodiscus  gigaSf  (Ehr.)    Marine. 

Disk  very  large,  cellules  not  very  large,  hexagonal,  radiate,  smaller 
towards  the  centre.   (PI.  26,  fi^.  21). . 

Ehr,  Mic,  T.  xviii.,  fig.  34.     Kiitz.  Bac,  p.  132,  T.  i.,  fig.  16. 

Stomachs  of  Ascidians,  dredged  on  the  coast  of  County  Clare. 


262  Proceedings  of  the  Royal  Irish  Academy. 

Coseinodiscus  radiatua,  (Ehr.)    Marine. 

Cellules  large,  hexagonal,  radiate,  somewliat  smaller  near  tlie 
margin. 

Ehr.  Mic,  T.  xx.,  fig.  1.  Kiitz.  Bac.,  p.  132,  T.  i.,  fig.  18. 
Wm.  8m.,  B.  D.,  Vol.  i.,  p.  23,  PI.  iii.,  fig.  37.  Balfs,  in  Pritcli., 
p.  830,  PI.  xi.,  figs.  39  and  40.  Heiberg,  De  Danske  Biat.,  p.  36. 
Clere,  Om  Syenska  och  NorakaDiat.,  p.  218.     Bab.  Fl.  Enr.,  p.  34. 

On  sea-weeds,  Bannow,  County  "Wexford.  Piles  of  wooden  bridge, 
Dollymount ;  Malahide.  Stomach  of  Pectens,  Dalkey.  On  corallines, 
Howth.  On  sea  weeds,  Ballybrack,  County  Dublin.  On  sea  weeds, 
Eilkee,  County  Clare.  Erom  stomachs  of  Ascidians,  coast  of  County 
Clare. 

Coseinodiseua  radiolatus,  (Ehr.)    Marine. 

Disk  small,  cellules  minute,  obscurely  hexagonal,  arranged  partly 
in  radiate  bands,  and  partly  in  the  intervals  of  these  bands  in  converg- 
ing lines.  Cellules  confused  at  the  centre  of  the  disk,  smaller  towards 
the  margin.     (PI.  26,  fig.  22.) 

Kutz.  Bac,  p.  132,  T.  xxix.,  fig.  91.  Ralfs,  inPritch.,  p.  830,  who 
describes  the  form  thus  : — ''  Cellules  punctiform,  equal,  radiating," 
whereas,  in  fact,  they  are  minutely  hexagonal,  and  diminish  slightly 
near  the  margin. 

Oyster  shells,  Dublin  Bay.  Tide-pool,"  Dalkey,  County  Dublin. 
Stomachs  of  Ascidians,  Boundstone  Bay,  County  Gal  way.  Stomachs  of 
Ascidians,  County  Clare. 

CoseinodisetM  eervinu$,  (Brightwell.)    Marine. 

Cellules  very  minute,  radiate,  close,  dry  valve  fawn-coloured,  fms- 
tule  convex. 

Brightwell  has  described  and  figured  this  form  as  Hyalodiscus  cer- 
vinus,  Q.  J.  M.  S.,  Vol.  viii.,  p.  95,  PI.  vi.,  fig.  13.  He  describes  the 
^*  puncta  or  dots  "  as  *'  scattered  over  the  whole  surface ;"  but  in  his 
figure  represents  them  as  regularly  radiate,  which  latter  corresponds 
exactly  with  my  specimens.  Ralfs,  in  Pritch.,  p.  831,  places  the  form 
among  the  doubtful  species  of  Coscinodiscus,  to  which  genus  it  pro- 
perly belongs. 

Prom  stomachs  of  Ascidians,  Boundstone  Bay,  County  Ghtlway. 
Prom  stomachs  of  Ascidians,  County  Clare. 

CadnodiscuB  Smithii,  (Wm.  Sm.)    Fresh  water. 

Disk  small,  punctate,  puncta  regularly  radiate. 

Wm.  Sm.,  B.  D.,yol.  i.,  p.  23,  PI.  iii.,  fig.  36. 

Smith  has  unaccountably  confounded  this  form  with  Coscinodiscus 
minor,  Ehr.,  from  which  it  is  plainly  distinguished,  both  by  its  habitat 
and  the  character  of  the  striation ;  the  latter  being  marine  and  areolate, 
the  former  a  fresh  water  species,  and  punctate. 


O'Meara — Report  ati  the  Irish  Diatofnacece.  263 

Balis,  in  Pritch.,  p.  818,  considerB  this  foim  may  be  identical  with 
Helosira  nivalis,  but  it  plainly  belongs  to  the  genus  Goscinodiscus. 

Lough  Neagh,  near  Lurgan,  County  Armagh.  Lough  Island-Eeayey, 
County  Down.   Biver  Blackwater,  near  KeUs,  County  Meath. 

Cascinodiscus  Normannij  (GFreg.)    Marine. 

Cellules  on  the  the  disk  small,  obscurely  hexagonal,  radiate, 
arranged  in  fascicles  of  about  six  lines,  decreasing  in  size  as  they  ap- 
proach the  margin  ;  valye  very  convex  in  the  centre. 

Grevnie,  Q.  J.  M.  8.,  Vol.  vii.,  p.  81,  PI.  vi.  fig.  3.  Balfs,  in 
Fritch.,  p.  830. — Coscinodiscus  fasciculatus,  O'M.,  Q.  J.  M.  8.,  New 
Series,  Vol.  vii.,  p.  249,  PI.  vii.,  fig.  1. 

Arran  Island,  County  Galway.  Stomachs  of  Ascidians,  Boundstone 
Bay,  County  Galway. 

CMcinodiacuB  nitiduSy  (Greg.)    Marine. 

Margin  of  the  disk  striated,  cellules  distant,  roundish,  large,  dis- 
tinctly radiate,  except  near  the  centre,  where  they  are  slightly  con- 
fused. Smaller  at  the  margin,  gradually  increasing  in  size  towards, 
the  centre. 

Greg.  Diat.  of  Clyde,  p.  27,  PL  x.,  fig.  45.  Balfs,  in  Pritch., 
p.  833,  PI.  viii.,  fig.  18. 

Arran  Island.  Stomachs  of  Ascidians,  Boundstone  Bay,  County 
Galway.  Malahide,'County  Dublin.  Bostrevor,  County  Down.  Kilkee^ 
County  Clare. 

Coseinodiseus  Grefforii,  N.  S.     Marine. 

Margin  of  the  disk  striated,  cellules  sub-quadrangular,  much 
smaller  than  in  the  former  species,  and  more  equal  in  size,  radiate ; 
a  small  vacant  angular  space  in  the  centre,  from  the  angles  of  which 
so  many  lines  of  cellules  run  to  the  margin,  the  interspaces  filled  up 
by  rows  of  cellules,  gradually  shortening.     (PI.  26,  fig.  23.) 

(Jregory,  Diat.,  from  Glenshira  Sand,  ft.  J.  M.  S.,  Vol.  v.,  PI.  i., 
fig.  50.  After  describing  Coscinodiscus  nitidus,  Gregory  remarks, 
**  this  pretty  disk  was  figured,  without  a  name,  in  my  last  Paper  on 
the  Glenshira  Sand  (Trans.  Mic.  Soc,  Vol.  v.,  PI.  i.,  fig.  60).  Having 
found  it  tolerably  frequent  in  Lamlash  Bay,  I  now  figure  a  perfect 
example,  which  provisionally  I  refer  to  Coscinodiscus."  Diat.  of 
Clyde,  p.  28.  TMs  form  may  easily  be  confounded  with  the  preced- 
ing, as  Gregory  has  done  ;  but  a  more  careful  comparison  of  the  many 
specimens  that  have  come  under  my  observation  convinces  me  the 
f onus  are  distinct ;  and  accordingly  I  give  to  the  present  the  naj^e 
of  Gregory,  who  first  discovered  it. 

Arran  Island.  From  stomachs  of  Ascidians,  Boundstone  Bay^ 
County  Gkdway.    Stomachs  of  Ascidians,  County  Clare. 


264  Proceedings  of  the  Boyal  Irish  Academy. 

(d).  Cettule$  radiaU  at  the  marsfin,  linear  in  the  eenUral  portion. 

Coseinodiseusjimhriatus,  (Ehr.)    Marine. 

Cellules  hexagonal;  small;  in^  the  central  portion  of  the  disk 
arranged  in  lines  crossing  in  qnincunz ;  towards  the  margin  radiate ; 
onaller  towards  the  margin. 

Ehr.  Mic.    Balfs,  in  Pritch.,  p.  829. 

Stomachs  of  Ascidians,  Connty  Clare. 

(e.)  CeUalee  mranged  variously. 

Coieinoddeems  marginatus^  (Ehr.)    Marine. 

Cellules  largCi  hexagonal,  arranged  in  irregularly  curved  lines, 
with  a  distinct  narrow  singly  costate  margin. 

Ehr.  Mic.  Ralfs,  in  Pritch.,  p.  829.  Weisse,  Recherches  Micro- 
scopique  sur  le  Ghiano,  Bui.  de  I'Academie  Imp.  de  St.  Petersburg, 
T.  xii.,  p.  122,  PI.  i.,  fig.  21. 

Stomachs  of  Ascidians,  Eoundstone  Bay.  Arran  Islands.  Stomachs 
•of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Coeeinodiicus  lineatus,  (Ehr.^    Marine. 

Cellules  rounded,  arranged  in  oblique,  parallel  lines. 

Ehrenberg,  in  his  Microgeologie,  gives  several  figures  under  this 
name.  One  of  them,  T.  xxii.,  fig.  6  a.  b.,  seems  scarcely  assignable  to 
the  genus  Coscinodiscus,  inasmudi  as  it  is  furnished  with  a  marginal 
circlet  of  nodules.  Besides  this  there  are  two  other  forms,  quite  dis- 
tinct :  one  in  which  the  stri®  are  Hnear,  to  be  immediately  described ; 
the  other,  the  present  form,  which  is  furnished  with  cellules  as 
described  ^bove. 

Ehr.  Mic.  Kutz,  Bac,  p.  131,  T.  i.,  fig.  10.  Ealfs,  in  Pritch., 
p.  830. 

Malahide.  Monkstown.  Dredgings  in  Bay,  Co.  Dublin.  Sea- 
weeds, "Wicklow.  Breaches  near  Newcastle,  Co.  Wicklow.  BiBomow, 
Co.  Wexford.  Stomachs  of  Ascidians,  Co.  Clare.  Stomachs  of  Asci- 
-dians,  Boundstone  Bay,  Arran  Islands,  Co.  Galway. 

CoBcinodiscua  Bhrmberaii,  N.  S.    Marine. 

Disk  striate.  Striffi  linear,  in  two  series,  crossing  each  other 
^bUqu^ly;    (Pl.  26,  fig.  24.) 

This  is  the  form  described  by  Ehrenberg  as  Cos.  lineatus,  Mic, 
T.  XXXV.,  A.  17,  fig.  7;  T.xxxv.,  A.  16,  ^.  3.  Weisse^  BaL  de 
TAcademie  de  St.  Petersburg,  Tom.  xii.,  PL  L,  fig.  20  a. 

Malahide.  Piles  of  wooden  bridge,  DoUylnount,  Co.  Dublin. 
Stomachs  of  Ascidians,  Boundstone  Bay,  Co.  Galway. 


O'M:BAJ0iA.—Itepof't  on  the  Irish  IXatomaeeas.  385 

Comnodkeua  minor,  (Ehr.)    Marine. 

Disk  small.  Cellules  roundishi  without  any.  perceptibla  anraage- 
ment.     (PI.  26,  fig.  25.) 

Ehr*  Mio.,  T.  xviU.,  fig.  31 ;  T.  acx.-i.,  fig.  28;  T.  xxii;,  fig".  27; 
T.  zix;,  fig.  3.  Kilts.  Bac.,  p.  131^  T.  L,  figs.  12,  13.  BaHv,  in 
Pzitch. ,  p.  88 1 .  Weisse,  Bedierohes  Microsoopiqnes  wax  le  Ghiano,  Bui. 
da  TAcadj^mie  Impwial  de  Baience  de  St.  Petetsbnrg,  T.  zii.^  p.<  121^ 
PL  i.,  fig.  22. 

Tide-pool,  Salkey,  Go.  DuUin. 

Comnodiseuspunetulatusy  (Greg.)    Marine. 

Striae  indistihcti  Disk  covered  with  what  appear  to  be  fine  punlcta, 
irregularly  scattered. 

Gregory  describes  the  diiAc  in  his  specimens  as  "  marked  by  very 
fine  and  o^ure  lines,  which,  near  the  margin,  *  are  traceable  as  rays,' 
Imt  which  soon  become  fainter,  and  apparently  wavy,  at  the  same 
tiiae  as  they  proceed  towards  the  centre.'^Biat.  ol 'Clyde,  p.  28. 

Several  specimens,  from  different  localities,  came  under  my  notice, 
bnt  all  taounted  in  balsam.  In  consequence  I  could  not  trace  the  lines 
referred  to ;  and,  moreover,  the  puncta  in  such  forms  as  were*  seen 
obliquely  had  the  appearance  of  fine  hairs.  This  circumstance  increases 
the  doubt  which  I  entertain,  in  common  with  Gregory  and  Balfs,  as 
to  whether  the  form  is  properly  referred  to  the  genus  Coscinodiscus. 

Gregory,  Diai  of  Clyde,  p.  28,  PI.  x.,  fig.  46.  Ealfs,  in  Pritch., 
p.  831. 

Arran  Islands.  From  stomachs  of  Ascidians,  Boundstone  Bay, 
Co.  Galway.     On  Fucus  serratus,  Ballybrack,  Co.  Dublin. 

Genus  YII.    Abachkoxdiscus,  Ehr.    Deane. 

Araehnoidiseus  Ehrenbergiij  (Bailey.)    Marine. 

''Disk  with  a  central  hyaline  nodule  or  uilibilicus,  and  numerous* 
radiating  lines,  counected  by  concentric  circles  of  large  pearly  granules ; 
the  circle  next  the  umbilicus  formed  of  short  Hues.'' — Ealfs. 

Wm.  8m.,  B.  D.,  Vol.  i.,  p.  25 ;  Supp.  PL  xxxi.,  fig.  266.  Ealfs, 
in  Pritch.,  p.  842,  PI.  xv.,  figs.  18-^21. 

This  truly  splendid  form  has  been  discovered  in  the  fossil  earths  of 
California,  and  in  a  living  state  it  has  been  gathered  in  Japan,  Cali- 
fornia, and  South  Africa.  It  is  its  habit  in  congenial  climates  to  sever 
completely  the  plants  to  which  it  is  attached.  It  admits  of  serious 
doubt,  therefore,  whether  the  few  isolated  specimens  which  have  been 
discovered  in  this  kingdom  entitle  it  to  be  included  among  our  British 
forms.  'Eabenhorst  does  not  give  it  a  place  among  the  European 
species  of  Diatomacess ;  and  perhaps  he  was  right  in  excluding  it.  But 
it  seems  desirable  to  notice  Uie  fact  of  its  having  been  found.    Besides 


266  Ffvceedings  of  tlie  Royal  LHah  Academy. 

the  case  mentioned  by  Smith,  Captain  Hntton  found  some  two  or  three 
specimens  in  a  gathering  made  by  him  at  Malahide,  Co.  Dublin,  as 
mentioned  in  the  Proceedings  of  the  Dublin  Microscopical  Club,  15th 
December,  1864 ;  Q.  J.  M.  8.,  April,  1865,  p.  167.  Had  these  forms 
been  found  in  the  proximity  of  a  harbour  resorted  to  by  foreign  vessels, 
it  might  be  suspected  they  were  imported  from  foreign  seas,  and 
deposited  as  the  vessels  unladed  their  freight;  but  such  a  supposi- 
tion cannot  be  entertained  regarding  Malahide.  I  was  present  at  the 
meeting  when  the  specimens  were  exhibited,  and  remember  that 
Captain  Hutton  informed  me  that  he  had  not  been  working  with  any 
materia]  likely  to  contain  these  forms,  and  that  he  was  confident  they 
were  taken  from  the  sea  at  Malahide,  as  the  vessels  used  in  the  pre- 
paration were  new,  and  had  not  been  used  before.  I  have  myself  to 
add,  that  a  single  frustule  was  recently  found  by  me  in  a  gathering 
made  by  Eev.  M.  H.  Close,  at  a  place  called  Drehidnamaud,  on  the 
coast  of  the  Co.  Kerry. 

In  the  same  gathering  which  yielded  the  specimens  of  Arachnoi- 
discus  Ehrenbergii,  Captain  Hutton  found  some  specimens  of  what  he 
regarded  as  Arachnoidiscus  omatus;  but  considering  it  likely  these 
latter  were  not  specifically  distinct,  I  only  refer  here  to  the  circum- 
stance as  corroborative  of  the  probability  that  Arachnoidiscus  Ehren- 
bergii was  found  at  Malahide. 

Genus  YIII.     Cbaspbdobiscus,  Ehr. 

Disk  not  undulate,  having  a  broad  border,  with  areolation  differing 
from  that  of  centre. 


Craapedodtseus  eoseinodtseuSf  (Ehr.)    Marine. 

Border  broad,  about  the  tlurd  of  the  entire  diameter,  areolate 
areoles  hexagonal.    Middle  portion  punctate.     (PI.  26,  fig.  26.) 

Bal£s,  inPritch.,  p.  832,  PI.  v.,  fig.  80. — Craspedodiscus  pyxidicula,. 
Brightwell,  Q.  J.  M.  S.,  1860,  p.  95,  PI.  v.,  fig.  4. 

Stomachs  of  Xscidians,  Broadhaven  Bay,  Co.  Galway. 

Genus  IX.     Activopttchtts,  Ehr. 

Disk  undulate,  divided  into  strongly  defined  somewhat  triangular 
compartments,  with  a  distinct  polygonal  centre,  the  sides  of  th& 
polygon  being  equal  to  the  number  of  compartments  into  which  the 
disk  is  divid^. 

The  valves  in  this  genus  appear  to  consiBt  of  two  distinct  plates^ 
with  a  striation  somewhat  different,  hence  the  species  have  by  some 
being  unnecessarily  multiplied. 


O'Meaiia — JSeport  on  the  Itnah  DiatatnacetB.  267 

Aetinoptyehui  senarwu,  (Ehr.)    Brookiah  or  maiine. 

Yalve  divided  into  six  Gompartments,  areolate,  areolse  more  or 
lc88  hexagonal.    In  this  species  the  valves  vary  considerably  in  size. 

Ehr.  Mic,  T.  xxi.,  fig.  18,  a.  b.  Kiitz.  Bac.,  p.  134,  T.  i.,  fig.  21, 
T.  xxi.,  fig.  26.  The  form  there  described  does  not  differ  from  that 
which  the  same  author  has  described  and  figured  as  Actinocyclus  undu- 
latus,  Bac,  p.  182,  T.  i.,  fig.  24.  Ralfs,  inPritch^  p.  839,  PI.  ix.,  fig. 
132. — ^Actinoptychus  undidatus,  !ELab.  Fl.  Eur.,  sect.  1,  p.  86. — 
JUtinocyclus  undulatus,  "Wm.  8m.,  B.  D.,  Vol.  i.,  p.  25 ;  Plate  v.,  fig» 
tt.  Heib.  Be  Banske  IHat.,  p.  3Y.  Cleve,  Om  SVenska  och  Norska 
Biat.,  p.  218. 

Salt  ditch  near  Wexford.  Bannow,  Co.  "Wexford.  Rostrevor, 
Co.  Bown.  Stomachs  of  Pectens,  Balkey.  BoUymount.  Portmamock, 
Co.  Bublin.    Sea  shore,  near  Ballysodare,  Co.  Sligo. 

Var.  denariuSf  (Ehr.)    Marine. 

Compartments  ten  in  number.    ISir.  Mic,  T.  xviii.,  fig.  23. 
From  stomachs  of  Ascidians,  Boundstone  Bay.    Arran  Islands, 
Westport  Bay,  Co.  Galway. 

Var.  duodenartM,  (Ehr.)    Marine. 

Compartments  twelve  in  number.  Ehr.  Mic,  T.  xviii.  f.  24. 
BaUs,  in  Pritch.,  p.  840.  Weisse,  Bulletin  de  L' Academic  Imp.  de 
St.  Petersbourg,  Tome  xii.,  p.  122,  T.  i.,  fig.  8. — ^Actinocyclus  duo- 
denarius,  Wm.  Sm.,  B.  B^  Vol.  ii.,  p.  86. 

From  stomachs  ol  Ascidiasis,  Bioundstone  Bay.  Airan  lahrnds,  Co. 
Oalway. 

Var.  iedenaritUf  (Ehr.)    Marine. 

Compartments  sixteen  in  number.  Ehr.  Mic,  T.  xviii.,  fig.  26. 
Weisse,  bulletin  de  L' Academic  Imp.  de  St.  Petersbourg,  Tome  xii., 
p.  122.  T.  i.,  fig.  9. — Actinocyclus  sedenarius,  Wm.  Sm.,  B.D., 
Vol.  ii.,  p.  86. 

Sea^weeds,  Bannow,  Co.  Wexford.  Arran  Islands.  From  sto- 
machs of  AscidianS)  Boundstone  Bay,  Co.  Galway. 

Var.  vicenariuBy  (Ehr.)    Marine. 

Compartments  twenty  in  number.  The  only  specimen  of  this 
variety  found  by  me  has  marginal  teeth  obvious  on  some  of  the  com- 
partments, though  not  noticeable  on  others,  owing  perhaps  to  the 
circumstance  of  the  valve  not  lying  quite  parallel  to  the  side.  These 
teeth  disappeared  altogether  when  the  form  was  mounted  in  balsam. 
Balfs,  in  Pritch.,  p.  840.  Weisse,  Bulletin  de  L' Academic  Imp. 
de  St.  Petersbourg,  Tome  xii^  p.  122. 

Brehidnamaud,  Co.  Kerry. 

a.  I.  A.  FBOC,  SBB.  n.^  TOI«.  n.,  SCIENCS.  2  M 


268  Proceedings  qf  the  Boyal  Irish  Academy. 

Genus  X.    Oxphalopxlta,  Ebr. 

Yalres  as  in  Actinoptyclius,  but  having  a  marginal  spine  in  each 
compartment. 

Omphahpelta  areohUa,  (Ehr.)    Marine. 

Yalve  having  six  compartments,  areolate ;  submarginal  spines  small. 

Ehr.  Mic,  T.  xxxv.,  A.  Ralfs,  in  Pritch.,  p.  841,  PL  viii.,  fig. 
16. — ^Actinocyclus  areolatus,  Brightwcll.  Q.  J.M.S.,  1860,  p.  93,  H. 
T.,  fig.  1. 

Airan  Islands,  Co.  Oalway. 

Genus  XI.    AcnyocTCLus,  Ehr. 

''Disk  minutely  and  densely  punctated,  or  cellulose,  generally 
divided  by  radiating  single  or  double  dotted  lines,  and  having  a  small 
circular  hyaline  intramarginal  pseudo-nodule."  ''The  disk  is  not 
undulated."  Kails.  To  this  description  may  be  added,  that  the 
species  of  this  genus  usually  exhibit  a  border  in  which  the  striae  are 
unlike  those  of  the  remainder  of  the  disk ;  the  stiiso  also  almost  or 
altogether  reach  the  centre. 


Aetinoeyelut  JRalfsii,  (Wm.  Sm.)    Marine. 

Valve  highly  irridescent  under  a  low  power.  Striae  radiate,  monili- 
f oim ;  puncta  nearly  of  uniform  size  throughout,  the  dividing  radii  equi- 
distant, nearly  reaching  the  centre ;  the  next  lines  of  puncta  consider- 
ably shorter  than  the  radii ;  the  next  again  still  shorter,  exhibiting 
numerous  subulate  blank  spaces;  border  tolerably  wide,  minutely 
punctate ;  submarginal  nodido  large,  round ;  no  central  nodule,  but 
the  central  portion  marked  by  a  few  scattered  puncta ;  diameter  about 
•0042.     (PL  27,  fig.  1.) 

Ralfs,  in  Pritch.,  p.  835,  PL  v.,  fig.  84.— Eupodiscus  Ralfsii,  Wm. 
Bm.,  B.  D.,  Vol.  ii.,  p.  86. 

Lough  Kay,  Co.  Kerry.  Stomachs  of  Pectens,  Dalkey  Sound,  Co. 
Dublin.    Stomachs  of  Ascidians,  Belfast  Lough,  Co.  Antrim. 

Aetinocyeltu  moniliformii,  (Ealfs.)    Marine. 

Strise  monilif orm,  principal  rays  about  twelve  in  number,  running 
radiately  from  centre  to  border ;  intermediate  rays  becoming  gradually 
shorter  and  parallel,  except  near  the  border,  where  a  few  short  ones 
meet  them  at  an  angle.  About  four  puncta,  closely  approximated  in 
the  centre,  present  the  appearance  of  a  nodule ;  border  narrow,  punc- 
tate; pseudo-nodule  sm^,  marginal.  Diameter  about  '0034.  (PL 
27,  fig.  2.) 


O'Meara — Be^rt  an  the  Irish  DiatofnacecB.  269 

I  have  had  considerable  difficulty  in  identifying  this  species ;  in 
some  respects  it  agrees  with  the  description  of  Eupodiscus  sparsus, 
Greg.,  a.J.M.8.,  1856,  p.  81,  PL  i.,  fig.  47.  But  as  it  more  nearly 
resembles  specimens  frequently  to  be  met  with  in  the  Kichmond 
deposit,  which  Ealfs  seems  to  hare  had  in  view  when  he  named  the 
species,  I  have  adopted  his  specific  designation. 

Balfs,  in  Pritch.,  p.  834. 

Salt  ditch  near  Wexford.    Sea-weeds,  Ballybrack,  Co.  Dublin. 

Aetinocyehu  craasus,  ^Wm.  Sm.)    Marine. 

Striffi  moniliform;  principal  rays  strongly  marked  when  viewed  by 
a  low  power;  arrangement  of  puncta  somewhat  confused;  border 
narrow,  punctate,  puncta  decussate ;  submarginal  nodule  small ;  dia- 
meter -0020. 

Balfs,  in  Pritch.,  p.  835. — ^Eupodiscus  crassus,  Wm.  Sm.,  B.D., 
Vol.  i.,  p.  24,  PI.  iv.,  fig.  41. 

Sea-weeds,  Ballybrack.  Stomachs  of  Pectens,  Dalkey  Sound, 
Malahide^  Howth,  Co.  Dublin.    Stomachs  of  Ascidians,  Co.  Clare. 

Aciinocyclu9  fidvua,  (Wm.  Sm.)    Marine. 

StrUe  moniliform,  close,  subradiate ;  border  broad ;  striation  indis- 
tinct; submarginal  nodule  small.    Diameter  about  *0025. 

Balfs,  in  Pritch.,  p.  835. — Eupodiscus  fulvus,  Wm.  Sm.,  B.D., 
Vol.  i.,  p.  24,  PI;  iv.,  fig.  40. 

Stomachs  of  Pectens,  Dalkey  Sound,  Co.  Dublin.  Stomachs  of 
Ascidians,  Boundstone  Bay,  Co  (Mway. 

Oenus  XIL     Eupodiscus,  Ehr. 
Valves  having  hom-likc  processes  springing  from  the  surface. 


Eupoduem  argtUy  (Ehr.)    Marine. 

Disk  large,  areolate;  areoles  irregular,  somewhat  angular,  radiately 
disposed ;  processes  three  or  four,  submarginal.  Diameter  fi*om  *0065 
to  -0120.     (PL  27,  fig.  3.) 

Vm.  Sm.,  B.D.,  VoL  i,  p.  24,  PL  iv.,  fig.  39.  Balfs,  in  Pritch., 
p.  843,  PIb.  vi.,  fig:  2,  and  zi:,  figs;  41,  42:  Heiberg,  De  Danske 
Diat.,  p:  37:  Bab.  Fl.  Eur.,  sect,  i.,  p.  819. — ^Tripodiscus  argus, 
Kiitz.  Bac.,  p.  136,  T.  i.,  fig.  6. 

Dublin  Bay. 

2M2 


270  Proceedings  of  tht  Hayal  Irish  Attidemy. 

Genus  XIII.    AtruflcuB,  18a*. 

Surtace  of  the  yalve  tutdulate,  tamiBked  wkk  two  lazge  prtoeMM; 
stiin  plumose,  airanged  in  form  of  a  qoatretoiL 


Auliseus  seulptus,  (Wm.  8m.)    Marine. 

Striae  linear.     (PL  27,  fig.  4.) 

Kalfs,  in  Pritch.,  p.  845,  PI.  vi.,  fig.  3.  GreviUe,  a  J.  M.S., 
1863,  p.  43,  PI.  ii.,  figs.  1-3.  Heiberg,  De  Danake  Diat.,  p.  87. 
Cleve,  Om  Svenaka  och  Noraka  Diat.,  p.  218. — ^Enpodiacua  aculptna, 
Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  25,  PI.  iv.,  fig.  42.— AulacodiacuB  atfnlp- 
tua,  Brightwell,  ft.  J.  M.  fik,  1860,  p.  94,  PI.  v.,  fig.  S. 

IfiailaMde.  Pilea  of  wooden  l^ridge,DollymoTmt,Oo.BtrMiii.  Sxrer 
Slangy,  at  Killurin,  Co.  Wexford.  Sea-wecda,  near  town  ti)  iTick^yw. 
Weatpoit,  Co.  Oalwaj. 

Qenua  XIY.    OnoKToniacTTa,  Ehr. 
Siflk  fumiaked  with  marginal  teeth. 


In  tibia  getfoa  I  have  nnited  Shrenherg'a  two  genera,  XMoxilodiacua 
and  Svatephania,  deemsng  tlie  distinction  between  l^em  ndt  of  aoffi- 
eient  importance  to  justify  their  aeparataon.  The  dislanclioii,  aa  ez- 
preeaed  by  Balfa,  ia  aimply  this,  that  in  Odontodiscna  *^4ihe  *dotB  are 
radiate,  not  parallel,  aa  in  Systephania." 

Odantodisctu  excsntrieusy  (Ehr.)    Marine. 

Disk  varying  in  size  from  '0008  to  '0025 ;  areolate ;  areolea  ronnd^ 
arranged  in  curved  exoentric  linea;  teeth  numeroua,  abort.  (PI.  27, 
fig.  5.) 

Ehr.  Mic,  T.  xxxv.,  A.  18;  fig.  11.  Balfa,  in  Pritch.,  p.  832. 
PI.  v.,  fig.  90. — CoBcinodiscuB  excentricns,  Kiita.  Bac.,  p.  131,  1).  i., 
fig.  9,  in  which  the  teeth  are  not  figured  or  deacribed.  Wm.  Sm., 
B.  D.,  Vol.  i.,  p.  23,  PI.  iii.,  fig.  38.— Eupodiscua  excentricua,  O'M., 
a  J.  M.  S.,  1867,  p.  249,  PL  vii.,  fig.  2. 

Sea-weeds,  !Bannow.  Salt  ditch  near  *Wexford.  ^ea  ot  wooden 
bridge,  Dollymount,  Malahide,  Stomachs  of  Pectens,  J)alkey,  JErom 
Condlines,  Howth,  Sea-weeds,  Ballybrack,  Co.  Dubl^.  Sea- weeds, 
Kilkee,  Stomachs  cif  Ajscidians,  Co.  t/lare.  Stoiiuichs  bi  Ascidiana, 
Eotindstone  Bay,  Co.  Galway. 

Odantodiscui  anglieuif  (Donkin.)    Marine. 

Diak  about  '0016  in  diameter ;  teeth  large  and  prominent,  oocnpy- 
ing'  a  tolerably  broad  unatriate  margin ;  striee  minutely  punctate,  decus- 
aately  arranged.     (PL  27,  fig.  6). 


O'lCsARA— i&?por^  on  the  Irish  Diatom^cecp.  271 

Stow^  of  AB<?iMiaT)ft»  Bpundatione  Bay,  Co.  Ctalwfty^ 

QjXmtodiiCtu  hAemiew^    K.  S«    Uavme* 

iiak  about  *00I8  w  diameter;  areolajte ;  areolea  rouacl^  dtocDMatoI} 
anasged,  reaohmg  the  circumference ;  teetli  more  numerous  than,  in 
f onner  spociea,  and  shorter.    (PL  27,  fi^  7.) 

StoauMha  el  AseUnaUy  Soundslone  Bay,  Co.  Qalwaj. 


A.  J^h4i^iA2^  sytnmetrieaL     Volvu  not  circular* 

yi,Mn»T  n.    BIDDXJLPBIELE,  Kutz. 

Yalyes  lanceolate,  in  some  cases  nearly  orbicular,  famished  with 
disiinot  processes  and  spines ;  oonneoting;  zone  largely  developed  in 
foU-grown  speoimois.  In  such  speoies  as  haye  been  seen  in  a  liTing 
stale  tlie  £nzstales  are  united  in  filaments. 


This  group,  established  by  E^iitzing  without  any  very  distinct  defini-. 
tion,  ombracecl  the  following  genera,  Isthmia,  Odontella,  Biddulphia,  and 
Zygoceros.  Balls,  in  Piitchard^  adopts  the  same  system  of  grouping, 
adcQng  to  those  above  named  two  other  genera,  Hemiaulua,  and  Sy- 
drosera,  but  giyes  more  distinct  chacactczifitioa  than  the  former  author. 
Hit  diagnQfiia  rests  mainly  on  ibe  oonvexity  of  the  frustules,  in  con- 
sequence of  which  the  lateral  yalyes  "  enter  largely  into  the  front 
yiew,"  and  on  tho  development  of  processes  on  the  yalyes.  Grunow 
adopts  the  group  with  no  more  distinct  definition  than  the  following. 
**  9ide  view  longish,  or  having  three,  four,  or  more  angles,"  and  in-, 
eludes  in  it  four  genera,  namely,  Isthmia,  Biddulphia,  Amphitetraa,and 
Tnceratium.  Heiberg  m^rks  the  group  by  the  fact  of  the  processes 
springing  from  the  vafve  obliquely  outwards,  and  places  und^er  it  the 
genera  Cerataulua,  Biddulphia,  Triceratium^  Amphitetra3'';  and  in  a 
sub-group  named  Biddulphies  cuneatae,  the  genus  Eucampia  ako. 
Imn^diately  connected  with  the  Biddulj^hiasB,  this  Danish  authoi^ 
plaoes  another  group,  the  Hemiaulidie,  nuunly  distinguished  from  tha 
former  by  this  one  feature,  that  the  processes,  instead  of  springiBA 
from  the  valve  obliquely,  are  placed  at  right  angles  with  the  plane  of 
the  base. 

The  genus  Isthmia  which  Kutsij^gi,  B^Ifs,  and  Grunow  include  in 
the  Biddulphieae,  differs  considerably  in  these  respects,  that  the  frus- 
tules on  tiiie  front  view  are  not  symmetrical,  ^nd  the  valves  are  not 
furnished  with  processes,  the  structure  which  Balfs  regarded  as  such 


272  Proceedings  of  the  Boyal  Irish  Academy. 

being  only  a  mucous  cushion  or  stipes,  and  on  these  grounds  the  genus 
Isthmia  ought  to  be  excluded.  In  the  case  of  Hjcbosera  (Wallich), 
the  frustules  are  not  symmetrical,  processes  occurring  on  the  one  Talre, 
and  not  on  the  opposite  one.  Wallich's  description  is  ''  on  one  side 
only,  with  a  remarkable  series  of  aperture-like  appendages."  Wallich 
on  !IViceratium,  Q.  J.  M.  S.,  July,  1858,  p.  251.  for  which  reason  I 
consider  the  genus  Hydrosera  is  not  properly  comprehended  in  the 
group.  The  species  marked  by  an  angular  outline  of  the  ralves  as 
Triceratium,  Amphitetras,  ftc,  howeyer  closely  related  to  the  Biddul- 
phies,  seem  however  to  possess  such  distinctive  peculiarities  of  struc- 
ture as  to  justify  their  being  placed  in  a  separate  group ;  and  if  any 
forms  of  the  genus  Hemiaulus  had  occurred  in  Irish  localities,  I  would 
have  been  disposed  to  include  them  with  the  BiddulphiesB  as  Eaben- 
horst  has  done  in  his  Flora  Europea  Algarum. 

Various  generic  names  have  from  time  to  time  been  introduced  by 
different  writers  to  designate  the  forms  of  this  group,  in  consequence 
of  which  much  confusion  has  arisen,  to  obviate  which  a  few  remarks 
are  here  necessary. 

The  generic  name  Biddulphia.  was  first  adopted  by  Gray,  and 
along  witii  Biddulphia  pulchella  embraced  some  heterogeneous  forms, 
which  latter  were  afterwards  removed  to  their  proper.places.  Agardh 
then  established  the  genus  Odontella  to  receive  the  single  species  now 
known  as  Biddulphia  aurita;  Ehrenberg  having  applied  the  name 
Odontella  to  a  species  of  Desmid,  as  Boper  informs  us,  Q.  J.  M.  S., 
Oct.,  1858,  p.  3,  substituted  for  it  the  designation  Denticella,  which 
was  thus  equivalent  to  Agardh's  Odontella.  The  forms  included  in 
these  genera,  Biddulphia  and  Denticella,  were  filamentous;  and 
Ehrenberg  having  found  kindred  forms  which,  without  sufficient 
examination,  he  considered  to  be  simple,  adopted  the  genera  Zygoceros 
and  Cerataulus,  the  former  for  those  free  forms,  as  he  thought  them 
allied  to  Biddulphia,  the  latter  to  Denticella.  Some  of  these  genera 
have  been  retained  by  succeeding  writers,  but  Smith  in  his  Synopsis 
has,  as  I  think,  wisely  dispensed  with  these  superfluous  subdivisions, 
and  included  the  forms  contained  in  them  under  the  one  generic 
name. 

Eabenhorst,  in  his  Flora  Europea  Algarum,  places  the  Biddulphiese 
in  close  connexion  with  the  septate  forms,  supposing,  as  I  imagine,  that 
the  costsB  on  the  valves  of  Bid.  pulchella  and  other  species  with  un- 
dulate surfaces  are  septa.  On  this  subject  the  observations  of  Smith 
are  worthy  of  notice  :  '*  The  existence  of  septa  in  B.  pulchella  is  by 
no  means  to  be  admitted,  though  the  costsB  may  occasionally  project 
into  the  interior  of  the  cells."    B.  D.,  Vol.  ii.,  p.  49. 

Genus  I.    BmnvLFHiA,  GFray. 

Processes  projecting  outwards  at  a  more  or  less  acute  angle  from 
the  plane  of  the  base. 


O'Meara — BepoH  on  the  Irish  Diatamaeea.  273 

(a.)  Surfaces  of  the  valves  not  undulate. 

BidduHphia  radiata,  (Wm.  Sm.)    Marine. 

Valve  nearly  circnlar ;  cellules  distinct,  ronndish,  radiate,  larger 
at  the  margin  than  towards  the  centre,  where  they  are  small  and  more 
distant ;  processes  two,  large,  alternating  with  two  others  smaller  and 
spine-like. 

It  is  with  some  difficulty  that  I  have  come  to  the  conclusion  that 
this  form  is  identical  with  that  described  by  Wm.  Smith,  first  as 
Eupodiscus  radiatus,  B.D.,  Yol.  i.,  p.  24,  PI.  xxx.,  fig.  255 ;  and  sub- 
sequently as  Biddulphia  radiata,  Yol.  ii.,  p.  48,  PI.  bdi.,  fig.  255. 
Keither  as  regards  the  outline  of  the  valve,  nor  its  areolation,  can  this 
form  be  regarded  as  obviously  the  same  as  that  described  in  Smith's 
figure,  which  is  perfectly  orbicular,  whereas  in  the  present  case  the 
outline,  though  nearly  circular,  presents  four  distract  angles,  the  pro- 
cesses being  placed  at  opposite  ends  of  one  diagonal  line,  the  spines 
occupying  the  corresponding  position  on  the  other.  Boper,  Q.  J.M.S., 
Oct.,  1858,  p.  19,  PI.  ii.,  fig.  29,  and  Balfs,  in  Pritch.,  p.  847, 
affirm  the  orbicular  outline  of  the  valve ;  but  Smith,  who  was  sub- 
sequently convinced  that  the  form  was  wrongly  placed  in  the  genus 
Eupodiscus,  and  that  its  proper  position  was  in  Biddulphia,  uses  such 
language  as  to  imply  that  the  outline  is  not  perfectly  circular.  Mark- 
ing the  distinctive  peculiarities  of  Eupodiscus  and  Biddulphia,  he 
says,  the  frustules  of  the  former  difPer  &om  those  of  the  laUer,  ''by 
the  orbicular  outline  of  their  valves."  B.  D.,  Vol.  ii.,  p.  48.  The 
present  form  differs  from  Smith's  figure  not  only  in  the  outUne,  but 
in  the  character  and  arrangement  of  the  cellules.  In  the  latter,  the 
•cellules  are  minute,  close,  and  not  radiately  disposed,  and  on  this  point 
Ealfs  alleges,  "  the  cellules  are  not  radiant,"  Pritch.,  p.  847.  The 
specific  name  given  to  the  species  by  Smith  is,  however,  suggestive 
of  the  thought  that  the  figure  is  at  fault  in  this  respect.  Roper's 
figure  of  the  species  exhibits  the  cellules  as  small  and  radiately 
arranged,  but  in  his  description  he  represents  them  just  as  they  are  in 
the  form  under  consideration,  ''as  ^stinctly  reticulated,  with  small 
but  rather  irregular  hexagons." 

Ccrataulus  Smithii,  Ralfs,  iu  Pritchard,  p.  847.  Cleve,  Om 
Svenska  och  Korska  Diat.,  p.  218.     Eab.  El.  Eur.,  sect,  i.,  p.  did. 

Salt  marsh  near  Ballysodare,  Co.  Sligo. 

Biddulphia  turgida,  (Ehr.)    Marine. 

Connecting  zone  transverse ;  valves  nearly  orbicular,  having  two 
large  truncate  processes,  and  two  alternate  spines  both  situated  diago- 
nally; a  circlet  of  small  marginal  spines  sometimes  present,  and 
numerous  minute  spines  scattered  irregularly  over  the  surface;  stria- 
tion  minutely  punctate,  the  puncta  arranged  in  close  wavy  lines. 

This,  as  well  as  the  former  species,  are  by  Balfs,  Heiberg,  Baben- 
horst,  and  Cleve,  placed  in  a  distinct  genus  named  Cerataulus,  the 


374  Proceedings  of  the  Royal  Irish  Academy, 

dutinctiTe  characteristic  being  the  fact  that  the  processes  and  spines 
are  diagonally  situated  on  the  valve. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  60,  PL  bdi.,  fig»  584.  Eoper,  ft.  J. 
M.  8.,  Oct.,  1853,  p.  17,  PL  ii.,  fig.  23.  Ralfs,  in  Pritch,  p.  846,  PL 
vi.,.  fig.  8.  Heiberg,  PeDanske  Diat,  p.  39.  Bab.  PL  £ur.,  sect  l^ 
p.  8J3. 

Salt  marah,  Ballysodare,  Co.  BUgo.  Sea-ireedB,  Malahide,  Co.  Dub- 
lin. 

Biddulphia  aurita,  (Lyngbye.)    Marine. 

Yalves  elliptical  lanceolate,  irith  the  processes  at  the  eztrendties- 
«l  the  longitudmal  axis;  prooenes  large  at  the  base,  rounded  off 
towaxds  the  fine  extremity ;  the  elevated  centre  of  the  valves  bearing^ 
three  fine  and  long  spines ;  striation  punctate,  fine ;  puncta  observed 
from  front  view,  parallel ;  connecting  zone  &iely  punctate.  (PL  27,. 
fig.  8a). 

Smith  and  Bopear  attribute  this  species  to  De  Br^bisson ;  but  with 
Balfs,  Heibcrg,  cmd  Rabenhorst,  I  consider  it  should  be  ascribed  to- 
Lyngbye,  who  first  described  it  as  Biatoma  auritum. 

Wm.  8m.,  B.D.,  VoL  ii.,  p.  49,  PL  xlv.,  fig.  819.  Boper,  ft.  J. 
M.  a,  Oct.,  1858,  p.  10,  PL  L,  fig.  8.  Ralfs,  in  Pritch.,  p.  849.  Hei- 
berg,  De  Danske  Diat.,  p.  41.  Bab.  PL  Eur.,  sect.  1,  p.  311.  Cleve, 
Om  Svenska  och  l^orska  Diat.,  p.  218. — ^Denticella  aurita,  £hr.  Mio., 
T.  XXXV.,  A  23,  fig.  7. — Odontella  aurita,  Kiita.  Bac,  p.  137,  T.  xxix.,. 
fig.  88. 

Stomachs  of  Ascidians,  Boundstone  Bay,  Co.  Galway.  Sea-weeds^ 
Ballybrack,  Malahide,  DoUymount,  Howth,  Co.  Dublm.  Bostrevor, 
Co.  l)own.  Tacumshane,  Co.  "Wexford.  Laytown,  Co.  Meath.  Bally-^ 
sodarOf  Co.  Sligo.    Dundalk,  Co.  Louth. 

Biddulphia  rhomhus,  (Ehr.)    Marine. 

Valves  orbicular-lanceolate ;  processes  at  the  extremity  of  the  longi- 
tudinal axis ;  spines  marginal ;  central  elevation  slight ;  striation  finely 
punctate,  seen  on  front  view,  parallel ;  connecting  zone  finely  punc* 
tato. 

Ehrenberg  described  this  form  as  Zygoccros  rhombus;  to  him,  there- 
fore, should  it  be  ascribed,  and  not  to  n  m.  Smith,  as  some  authors  hav& 
done. 

Wm.  8m.,  B.  D.,  YoL  ii.,  p.  49,  PL  Ixi.,  fig.  320.  Roper,  ft.  J.  M.  S., 

Oct.,  1858,  p.  11,  PL  L,  fig.  4.  Heiberg,  De  Danske  Diat,  p.  40.  Rab.,. 

Fl.  Eur.,   sect.  1,  p.  311.     Cleve,   Om    Svenska  och  Norska  Diat. „ 

218. — ^Zygoceros  rhombus,  Ehr.,  BerL  Acad.,  1839,  p.  166.     Kiitz* 

ac,  p.  138.  T.  xviii.,  fig.  9.     Ralfs,  in  Pritch,  p.  850. 

Maiahide,  Baldoyle,  Ballybrack,  Dollymount,  Co.  Dublin. 


O'Measa — Bepori  an  the  Irish  Diatotnacece.  275 

Biddndphia  haikifii^  {Wm.  Sm.)    Mazme. 

Frustoles,  on  frost  yiew,  receduog  at  the  aides  in  a  goatle  slope ;  ^id 
aurfaces  nearly  flat,  with  two  flight  elevatbns  on  which  the  spines  are 
atuated ;  processes  long^  and  narrow  towards  the  eadxemity,  slightly 
cnrving  inwards ;  stiiation  very  obsonxe.;  punctate;  puncta  pajuQeL 
Qa  side  Tiew  Talves  broadly  elliptieal ;  processes  at  extremitiea  of  the 
longitudinal  axis ;  spines  two,  sitnated  a  little  to  the  right  and  left 
of  same,  ahont  one-third  of  the  entire  length  from  extremities ;  striss 
Tery  fine ;  lines  of  pnncta  appearing  to  cross  each  other,  except  upon 
a  vacant,  sigmoid,  narrow  space  in  the  middle.    (PI.  27,  fig.  8.) 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  60,  Pis.  xIt.  and  Ixii.,  fig.  822.  Eab. 
PI.  Eur.,  sect.  1,  p.  811.  Koper,  a  J.  M.S.,  Oct.,  1858,  p.  12, 
PL  i.,  figa.  5-9. — ^Zygoceros  mohiliensis,  Ealf^,  in  Pritch,  p.  850, 
PL  yL,  fig.  11. 

Salt  dstch  near  Wexford.  Tacomshane,  Co.  Wexford.  Dvmdallc^ 
Co.  Lottth.     Salt  marsh,  Drehidnamaud,  Co.  Xerry. 

(b.)  8tiirfae$9  of  the  valves  yndtdate, 

Bidduiphia  puleheUa^  (Gbay.)    Marine. 

On  front  view  the  sides  inoUne  inwards  towards  the  processes ;  th» 
ralves  divided  into  compartments,  fr(»a  three  to  seven  in  number,  the 
central  being  the  largest  and  most  elevated,  from  which,  in  perfect 
specimens,  two  or  three  spines  are  projected ;  compartments  separated 
by  what  appear  strong  costce ;  processes  short,  rounded  at  extremities; 
striation  areolate;  areoles  roundish,  and  nearly  parallel;  connecting 
2one  striate.  On  side  view  the  valve  is  broadly  elliptical ;  areoles 
ranged  round  the  central  point.     (PL  27,  fig.  9.) 

Wm.  Sm.,  B.B.,  VoL  ii.,  p.  48,  Pis.  xliv.,  xlv.,  xlvi.,  fig.  821. 
Boper,  Q.  J.  M.  S.,  Oct.,  1868,  p.  7.  Ralfs,  in  Pritch,  p.  848,  PL  ii., 
figs.  46r-50. — ^Biddulphia  trilocularis ;  B.  quinquelocularis ;  B.  septem- 
locularis,  Kutz.  Bac.,  p.  188,  T.  xxix.,  fig.  89,  T.  xix.,  fig.  1,  T.  xix., 
fig.  2. — ^Biatoma  Biddulphianum,  Agardh,  Syst.Alg.,  p.  5. — Benticella 
Biddulphia,  Ehr.,  Berl.  Trans.,  1843. 

Malahide,  Ireland's  Eye,  BaldoyK  CJo.  Dublin.  Sea-weeds, 
Giants'  Causeway,  Co.  Antrim.  Stomachs  of  Ascidians,  Boundston^ 
Bay,.  Arran  Islands,  Co.  GULway. 

Familt  m.    TBICERATIElZE. 

Yahres  on  side  view  presenting  three  or  more  angles,  with  a  pro* 
springing  from  each  angle. 


This  group  includes  the  genera  Amphitetras,  Triceratium  and  Trina* 
oris,  wliKh,  m  consequence  of  their  obvious  resemblance,  are  placed 


276  Proceedings  of  the  Royal  Irish  Academy, 

liere,  although  differently  arranged  by  other  authors.  Wm.  Smith, 
Tecognifling  tiie  affinity  between  Biddulphia  and  Amphitetras,  placed 
them  dose  together,  but  astigned  to  Triceratium  a  widely  different 
position  in  his  system  of  arrangement.  Kiitzing  distributes  the  in- 
cluded genera  in  two  distinct  groups — ^the  AngulifersB  and  Angulatse, 
between  which  he  interposed  ^e  &ddulphie»  and  Tripodiscus  argus 
a  EupodiscuB  argus.  The  Angulifene,  he  says,  ''  are  easily  distin- 
guished by  means  of  their  angular  side  view ; "  but  of  the  Angulatce, 
which  embraces  only  the  single  genus  Triceratium,  he  gives  no  other 
diagnosis  than  that  contained  in  the  description  of  that  genus,  ''  indi- 
yiduals  free,  with  the  bivalye  lorica  triangular,  not  concatenated," 
Balfs  omits  Trinacria,  a  genus  established  by  Heiberg  subsequentiy  to 
the  publication  of  the  ''  History  of  the  Infusoria,"  and  along  with  the 
other  genera  placed  in  the  present  group  includes  Euodia,  and  Hemi- 
iiiscus.  Of  Hemidiscus  I  have  never  seen  a  specimen,  and,  therefore, 
can  express  no  opinion  regarding  it ;  but  as  to  Euodia,  from  the  cuneate 
outline  of  its  transverse  section,  it  plainly  should  be  excluded  from  this 
group,  with  which  it  has  little,  if  any,  affinity.  Balfs  indicates  two 
f eatiu*es  by  which  the  forms  in  this  group  may  be  distinguished  from 
the  Biddulphieee :  ''  The  angles  on  the  front  view  are  usually  less 
elongated,  and  the  intervening  margin  less  lobed."  Of  these  charac- 
ters the  latter  can.  scarcely  be  sustained  in  all  cases ;  and  as  to  the 
former,  if  Trinacria,  in  which  the  processes  at  the  angles  are  very 
long,  is  to  be  admitted  here,  this,  too,  must  be  regarded  as  by  no 
means  a  satisfactory  diagnosis.  Grunow  does  not  refer  to  Trinacria, 
for  the  same  reason  as  llalf s,  but  includes  the  other  forms  of  this  group 
under  the  Biddulphieee,  which  he  thus  defines :  **  Yalves  on  side  view 
longish,  or  three,  four,  or  more  angled,"  no  reference  being  made  to  the 
processes  springing  from  the  angles  which  constitute  so  remarkable  a 
feature  of  these  forms.  According  to  this  author,  the  characteristic 
distinction  between  Amphitetras  and  Triceratium  is  the  possession  of 
four  angles  by  the  former,  while  the  latter  has  but  three.  The  fact 
that  specimens  of  the  former  occur  with  five  angles,  and  of  the  latter 
with  four  or  more  angles,  evinces  how  untenable  is  this  distinction  as  a 
generic  diagnosis. 

Heiberg  includes  Amphitetras  and  Triceratium  in  the  Biddulphieee, 
and  his  genus  Trinacria  in  another  group,  namely,  the  HemiaulidsB ; 
the  main  distinction  of  which  rests  on  the  form  and  position  of  the 
processes,  which  are  triangular,  and  spring  at  right  angles  from  the 
basal  plane  of  the  valve.  But  these  ^fferences,  though  sufficient  to 
establish  generic  distinction,  seem  scarcely  to  justify  the  establishment 
of  a  distinct  group  to  receive  the  forms.  It  will  thus  appear  that,  in 
consequence  of  the  projection  of  the  processes  from  the  angles  of  the 
valves,  the  relationship  of  this  group  to  the  Biddulphieas  is  recognised 
by  most  authors  :  but  no  more  satisfactory  distinction  between  Am- 
phitetras and  Triceratium  has  been  suggested  than  that  in  the  former 
the  frustules  are  concatenate,  and  in  the  other  free.  This  distinction 
I  adopt,  not  because  I  consider  the  supposed  fact  on  which  it  rests  in 


O'Meara — Repoi*t  on  the  Irish  Dtatomacets.  277 

all  cases  sabstantiated  by  observatioii,  but  because  it  seems  the  most 
satisf actoiy.  And  not  being  in  a  position  either  to  sustain  or  refute 
the  assumption,  I  consider  tiie  proper  course  is  to  leave  them  as  they 
stand. 

Genus  I.     AMPmrEXEiSy  Ehr. 

Frustules  concatenate ;  cubical ;  processes  springing  from  each  angle 
of  the  valve  short. 

AmphiUtroB  antediltwiana,  (Ehr.)    Marine. 

Striation  areolate ;  connecting  zone  more  finely  areolate  than  the 
valve.  On  side  view,  margins  deeply  concave ;  areoles  radiate  and  con- 
centric.    (PL  27,  fig.  lOj 

Kiitz.  Bac.,  p.  135,  T.  xix.  fig.  3;  T.  xxix.  fig.  86.  Ralfs,  in 
Pritch.,  p.  858.  Heiberg,  De  Danske  Diat.,  p.  42.  Kab.  Fl.  Eur., 
sect.  1,  p.  318. — ^Amphitetras  antediluviana,  p,  W.  Sm.,  B.  D.,Vol.ii. 
p.  47,  PI.  Ldv.,  fig.  318  a'". 

Stomachs  of  Ascidians,  Boundstone  Bay,  Arran  Islands,  Co. 
Oalway. 

Variety  a, — On  side  view,  sides  parallel. — ^Amphitetras  antediluvi- 
ana, Wm.  S.,  B.  D.,  Vol.  ii.,  p.  47,  PI.  xliv.,  fig.  318.  Kalfs,  in 
Pritch.,  p.  858,  PL  xi.,  figs.  21  and  22. 

Stomachs  of  Ascidians,  Boundstone  Bay.  Arran  Islands,  Go.  Gal- 
way.  Malahide.  Dublin  Bay.  Howth,  Co.  Dublin.  Bundoran,  Co. 
Donegal. 

Variety  b. — With  five  angles. 
Stomachs  of  Ascidians,  Boundstone  Bay,  Co.  Galway. 

Genus  U.     TKiCBKA.Tn7M,  Ehr. 

Frustules  simple ;  normally  triangular  on  side  view ;  processes 
short,  roundish,  springing  outwards,  at  an  acute  angle  to  tiie  basal 
plane. 

Triceratium  favus,  (Ehr.)    Marine. 

Striation  areolate ;  areoles  hexagonal,  large;  sides  straight  or  slightly 
convex. 

Kutz.  Bac,  p.  139,  T.  xvii.,  fig.  11.  Wm.  Sm.,  B.  D.,  VoL  L, 
p.  26,  PL  v.,  fig.  44  ;  Supp.  PL  xxx.,  fig.  44.  Balfs,  in  Pritch.,  p.  855. 
PL  xi.,  fig.  43.  Heiberg,  De  Danske  Diat.,  p.  41.  Bab.  FL  Eur., 
sect.  1,  p.  315. 

Stomachs  of  Ascidians,  Boundstone  Bay,  Co.  Galway. 


^78  Proceedings  of  the  Royal  Irish  Academjf. 

TriceraUun^  aUemant^  (Bailey.)    Marim). 

Sides  neavly  straight;  stciatioiL  areolate;  areolee  small,  loandidi; 
radiating  towards  the  three  angles ;  bases  of  the  processes  nuurked  by 
what  seem  well  defined  costsB.     (PI.  27,  fig.  11.) 

Bailey,  Mic.  Observations  made  in  Sth.  Carolina,  Smithsonian  Con- 
tributions, Vol.  ii.,  p.  40.  Brightwell,  Q.  J.  M.  S.,  Vol.  i.,  p.  251, 
PL  vi.,  fig.  19.  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  26,  PI.  v.,  fig.  45.  Supp. 
PL  xxz.,  Hg.  45.  lUOfs,  in  Pritch.,  p.  854,  PL  tI.,  &g.  21.  Bab. 
FL  Eur.  sect.  1,  p.  316. 

ICud  of  Biver  Liffey,  Co.  Dublin. 

Trifieratium  amhfyoosros,  (Ehr.)    Marine. 

Sides  conyez ;  angles  broadly  rounded  oS ;  ceUules  radiate,  distant, 
roun^uh ;  more  deeply  shaded  at  the  borders.    (PL  27,  fig.  12.) 

Ehr.  Mic.,  T.  xviii.,  fig.  51.  Brightwell.  Q.  J.  M.  S.,  VoL  L, 
p.  25Q,  PL.iy.^  fig.  14.    Balis,  in  Pritch.^  p.  857. 

Stomachs  of  Poolbeg  oysters.    Dublin  Bay. 

TVieeratiuM  sxiguum,  (Wm.  Sm.)    Fresh  water. 

Valve  very  minute ;  areoles  minute ;  angles  elongated ;  sides  in- 
flexed.    (PL  27,  fig.  13.) 

Wm.  Sm.,  B.  D.,  VoL  ii.,  p.  87.  Brightwell,  Q.  J.  M.  S.,  1856, 
p.  274,  PL  xvii.,  fig.  1.    Balfs,  in  Pritch.,  p.  857,  PL  vi.,  fig.  16. 

Eirer  Liffey,  Co.  Dublin. 

Genus  III.     Teinacbia,  Heiberg. 

Frustules  normally  triangular ;  processes  springing  from  the  sur- 
face at  a  right  angle,  and  surmounted  by  two  curved  i^ines ;  transverse 
section  of  the  processes  triangular. 


Trinacria  regina,  (Heiberg.)    Marine. 

As  but  one  specimen  of  tms  species  has  been  met  with  by  me,  and 
that  mounted  in  balsam,  instead  of  giving  my  own  diagnosis  I 
consider  it  better  to  transcribe  the  exhaustive  description  of  Heiberg. 

''  Outline  of  the  basal-surface  triangular,  with  an  extended  de- 
pression towards  the  centre  and  the  short  pointed  angles.  The  out- 
line of  the  side  view  less  than  that  of  the  basal-sturface,  its  sides 
bulged  in  the  middle,  and  evenly  depressed  on  both  sides  of  the  same. 
The  side-surface  separated  from  the  &ont  surface  by  a  thick  projecting 
border.  The  end-processes  of  varying  height,  with  a  prominent  keel 
on  the  outer  margin ;  spines  slightly  crescentio.  The  portion  of  the 
side-surface  lying  between  the  processes  at  the  angles  forms  a  gently 
elevated  ridge,  which  again  has  a  slight  depression  towards  the  middle 


O'Meara — Report  on  the  Irish  DiatomacecB.  67d 

point.  The  striatioii  of  the  valTes  formed  of  moderately  Scattered 
granules,  arranged  in  curved  radiating  lines,  slight  or  absent ;  about  the 
middle  poiift,  more  rdbust,  and  consistrng  of  angulair  granules  arratiged 
in  three  or  four  longitudinal  lines,  and  in  short  transverse  Hnes  diverg- 
ing towards  tiie  stitQre,  or  that  portion  of  the  idde-surface  of  the  valve 
which  lies  between  eadh  pair  of  end-processes.  Oranifles  about  22  in 
0.05"**  along  the  suture ;  striation  oi  the  connecting-z6ne  unknown; 
length  of  tike  side  of  the  basal  surface  =  O-055"*  -  0*1  TS"".** 
This  beautiful  form  I  considered  to  be  an  undescribed  species  of 
Triceratium,  until  I  saw  Heiberg's  figure  of  Trinacria  regina,  Vhen  I 
■at  once  recognised  its  identity.  (PI.  27,  fig.  14). 
Heiberg,  De  Danske  Diat.,  p.  50,  T.  iii.,  fig.  7. 

Arran  Islands,  Co.  Galway. 

In  reference  to  the  locality  of  this  form,  Seiberg  aays : — ''  It 
-oocurs  abundaiftly  in  the  brown  Moleer  from  Fuur,  in  which  ft  is  one 
of  the  most  oommon  forms.  In  the  white  Moleer  I  have  found  GiSuf 
a  few  «itigle  specimens.*'  It  is  tihen  a  teaitter  of  interest  to  disoover 
it  <Al  cwr  own  <;oast&. 

Family  IV.    ISTHMIEiE,  AgardCh. 

Frustules  trapezoidal  o^  front  view,  on  the  side  view  ^broadly 
elliptical,  without  processes;  one  valve  having  the  extreme  comer 
produced,  at  the  end  of  which  is  secreted  the  mucous  cushion  by  which 
fmstule  is  imited  to  fnultule,  so  as  to  form  aa  irregularly  tomdhed 
filament. 


In  a  classification  founded  on  the  symmetrical  or  unsymmetrical 
ishape  of  the  frustule,  this  fauuly  should  in  strictness  be  assigned  to  a 
different  poBition ;  bi^  I  place  it  here  not  only  in  deference  to  the 
views  of  all  autiiors  known  to  me,  but  because  in  point  of  fact 
it  presents  considerable  analogy  to  the  Biddulphieae,  and  without 
violence  could  not  be  suitably  placed  at  a  distance  from  that 
jproup. 

OeniK  I.    I^rmciA,  Agatfiffii. 
Characters  of  the  Oenns  those  of  the  Family. 


Isthmia  nervna,  (Eiitz.)    Marine. 

Btriation  of  valves  areolate ;  areoles  large,  close,  s<Mnewhat  heza- 
-gonal,  with  numerous  strong  aaastomosing  costsB  springing  from  the 
margin,  and  disi^pearing  towards  the  middle  of  the  valve ;  connectiQg 
membrane  areolate,  axeoles  ^nuch  smcQler  than  those  on  the  valve 
(PI.  27,  fig.  15.)  

Kiitz.  Bac.,  p.  137,  T.  xix.,  fig.  5.     "Wm.  Sm.,  B.  D.,  Vol.  ii.. 


280  Proceedings  of  the  Royal  Irish  Academy. 

p.  62,  PL  xlvii.     RalfB,  in  Pritch.,  p.  581.      Eab.  Fl.  Eur.,  sect.  1, 
p.  309. 

This  and  the  following  fipecies  have  been  deBcribed  by  different 
authors  under  different  generic  and  specifio  names,  e,  g,y  Isthmia  obli- 
quata,  Ag. ;  Diatoma  obliquatum,  Ljng. ;  Isthmia  obliquata  tenuior^ 
Ag. ;  Conferya  obliquata^  Engl.  Bot.,  tab.  1869 ;  but  as  it  is  not 
certain  in  all  cases  which  of  the  two  species  was  intended,  it  seems, 
better  not  to  attempt  further  identification. 

Collected  in  great  abundance  by  Dr.  D.  Moore  on  Polysiphonia  in 
Camlough  Bay,  Co.  Antrim ;  and  found  by  me  in  almost  eyery  marine 
gathering  from  that  place  northwards,  but  not  at  all  in  the  same  pro- 
fusion.    Malahide,  Co.  Dublin. 

Isthmia  enervis,  (Ehr.)    Marine. 

Striation  of  Talves  areolate,  areoles  quadrangular ;  without  costffi  ; 
areoles  on  connecting  membrane  much  smaller,  and  roundish. 

The  frustules  are  generally  slighter  than  in  the  former  species^ 
but  the  distinctiye  characters  are,  first,  the  absence  of  the  costee,  and 
secondly,  the  want  of  a  distinct  border  on  the  yalye  in  side  view,  sa 
conspicuous  in  Isthmia  nervosa. 

Kiitz.  Bac.,  p.  137,  T.  xix.,  fig.  4.  Wm.  Sm.,  B.  D.,  Vol.  ii.^ 
p.  52,  PL  xlviii.  Ralfs,  in  Pritch.,  p.  851,  PL  x.,  fig.  183.  Rab. 
El.  Eur.,  sect.  1,  p.  309. 

Stomachs  of  Ascidians,  Eoundstone  Bay.  Arran  Islands,  Goi^ 
Galway.    Malahide,  Co.  Dublin. 

Family  V.     FRAQILARIE-^,  Kutz. 

Frustules  in  front  view  rectangular,  without  median  line,  central 
nodule,  or  internal  diaphragms.  The  frustules  are  usually  attached 
by  a  stipes,  or  united  together  in  parallel  or  zig-zag  filaments. 


The  group  thus  limited  embraces  the  following  genera : — Fragi- 
laria,  Denticula,  Odontidium,  Plagiogramma,  Dimeregramma,  Diatoma, 
Synedra,  Eaphoneis,  and  is  tolerably  well  defined  by  the  common 
characteristics  above  specified.  In  the  case  of  Eaphoneis  indeed  it  i& 
doubtful  whether  the  frustules  are  free  or  stipitate.  I  have  never  seen 
them  in  a  growing  state,  but  in  other  respects  they  exhibit  the  com- 
mon character  of  the  Fragilarie®. 

The  above  genera  have  been  distributed  by  different  authors, 
very  differently  from  their  present  arrangement.  Eiitzing  grouped 
such  of  the  above  genera  as  were  known  to  him  under  the  Fra^ariese^ 
with  the  exception  of  Synedra,  which  he  and  others  have  unaccount- 
ably, as  it  appears  to  me,  placed  under  the  SurireUesB.  William 
Smitii,  who  attaches  great  importance  to  what  others  have  regarded  a» 


O'Meara — Report  on  the  Irish  Diatomaeem.  281 

a  subordinate  feature — ^namely,  the  attaclimeiit  of  the  fnistules  in  fila- 
ments— ^has  accordingly  placed  together  snch  of  the  aboye-mentioned 
genera  as  seem  to  have  been  known  to  him,  with  the  exception  of 
Bynedra,  which  he  has  ranged  immediately  after  Pleurosigma.  The 
position  thus  assigned  to  Synedra  may  possibly  be  owing  to  his  sup- 
posing that  the  median,  longitudinal,  narrow,  unstriated  space,  and 
the  unstriated  central  space,  which  some  of  the  forms  present,  are 
analogous  to;  the  median  line  and  centred  nodule  of  the  Nayiculacess. 
Orunow  has  adopted  a  group,  which  he  has  named  DiatomesB,  dis- 
tributed into  two  sub-groups,  distinguished  by  the  absence  of  dia- 
phragms in  the  one,  and  the  presence  of  this  structure  in  the  other. 
The  former  v&rj  nearly  corresponds  with  FragilariesB  as  here  defined. 
The  genera  which  Grunow  includes  in  the  first  sub-group  of  Diatomee 
are  Odontidium,  Diatoma,  Plagiogramma,  Fragilaria,  Simeregramma, 
his  new  genus  Cymatosira,  Grammonema,  Eaphoneis,  Doryphora, 
Bynedra,  Asterionella,  and  Desmogonium.  Of  these,  Grammonema  is 
considered  by  Ealfs,  Kiitzing,  Ehrenberg,  and  Meneghini,  as  not 
diatomaceous.  If,  howexer,  it  belong  to  the  DiatomacesB,  as  I 
think  it  does,  its  proper  position  is  with  the  FragilariesD.  Dory- 
phora,  Grunow  describes  as  a  stipitate  Eaphoneis,  wMle  in  reality  it  is 
a  stipitate  Navicula,  and  should  therefore  be  ranked  with  the 
Kaviculaceee.  Asterionella  should  be  excluded  from  this  group, 
in  consequence  of  its  unsymmetrical  outline,  both  on  the  front 
and  side  yiews;  while  the  general  characters  of  Desmogonium  are 
those  of  the  Fra^aricae.  Balfs  adopts  FragilariesB  as  the  designation 
of  a  group  in  which  he  includes  Denticula,  Plagiogramma,  Odon- 
tidium, Fragilaria,  Grammonema,  Diatoma,  all  of  which  are  placed  by 
me  in  the  present  group ;  but  he  adds  also  the  following  yery  hetero- 
geneous genera: — ^Asterionella,  Nitzschia,  Ceratoneis,  and  Amphi- 
pleura;  while  Synedra,  Desmogonium,  Dimeregramma,  Staurosira, 
Baphoneis,  under  which  he  includes  Doryphora,  are  ranged  under 
the  Surirelleee.  These  latter  genera  seem  to  haye  little  in  common  with 
the  Surirelle»,  while,  with  the  exception  of  Doryphora,  already  referred 
to,  they  exhibit  the  general  features  of  the  FragilaricsB  ;  Asterionella^ 
l^itzschia,  and  Ceratoneis,  which  is  unnecessarily  separated  from 
Nitzschia,  on  account  of  haying  unsymmetrical  frustules,  are  incon- 
gruously forced  into  this  group  ;  and  Amphipleura,  by  its  conspicuous 
median  line,  is  more  analogous  to  the  Nayiculacesd.  Lastly,  Heiberg 
adopts  Kiitzing's  group  of  Fragilarieie,  which  he  diyides  into  two 
sub-groups — ^Fragilarieas  genuinss,  and  EragilarieaB  cuneatse.  The 
former,  so  far  as  it  extends,  corresponds  with  the  present  group, 
while  the  genera  contained  in  the  latter,  Meridion  and  Asterionella, 
seem  so  incongruous  that  they  should  be  placed  in  a  widely  difPe- 
Tcnt  position. 

Genus  I.     Fragilaiiia,  Lyngb. 
Frustules  on  front  view  more  or  less  perfectly  quadrangular. 


282  Froceidiftgs  of  the  Bayal  Irith  Aeademjf. 

iizdted  in  fikmeiita,  in  which  they  are  panllel;  eonsectingsaBetupiiAlly 
Tery  nazrow;  «bi«  on  the  side  view  very  fine,  nsaally  persisteat^  «i4 
appearing  en  the  frcmt  view,  where  they  {oi«in  «  nanDw  mfirgm. 


IV4iffilariacapueina,  (Desmaziereft.)    Fresh  water. 

ProBtttleB  flftt,  BO  tiiat  the  bead  oi  etriffi  appearing  on  ^e  iront 
Tiew  is  very  narrow.  On  side  view  the  valvea  are  nazroir,  tineas, 
with  either  acute  or  slightly  rounded  apices ;  rtrin  very  ine,  per- 
sistent. 

This  species  iaclitdes  Fragilaria  aonta,  which  is  scarcely  distin- 
gnishable  from  it. 

Eutz.  Bac,  p.  45,  T.  zvi.,  fig.  3.  Eab.  Sussw.  Diat.,  p.  33 ;  T.  L, 
fig.  2.  Wm.  Sm.,  B.D.,  Vol.  ii,  p.-22,  PL  xxxT.,  fig.  296.  Baifs,  in 
Pritdb.,  p.  776.  Orunow,  Yerhaad  der  K.  K.  ZwA.  Bot.  Gesel.,  Band 
xii^  1B62,  p.  372.  Castracane,  Catalogo  di  IKat.  racoolte  neUa  YaL 
Intrasca,  p.  15. 

This  species  is  of  almost  nniversal  occiorenoe. 

Dragilaria  mrsseent,  (Balls.)    Freah  water. 

Frustules  more  aidied  than  in  the  preceding  Bpecies,  and  the 
marginal  line  of  striae,  as  seen  on  the  front  view,  therefore  wider. 
On  side  view  linear,  or  slightly  elliptical ;  narrowed  at  the  end^  but 
not  constricted ;  strue  fine,  pemistent. 

Balls,  A.  N.  H.,  Vol.  xii.,  PI.  ii.,  fig.  6.  Kiitz.  Bao.,  p.  46,  T.  xvi^ 
fig.  4.  &ab.  Siissw.  Diat.,  p.  33,  T.  i.,  fig.  1.  Wm.  Sm.  B.  D.,  Vol.ii, 
p.  22,  PI.  XXXV.,  fig.  297.  Ralls,  in  Pritch.,  p.  777.  Grunow,  Verhand 
der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  373,  T.  iv.,  iS^.  15. 
Heibeig,  De  Danske  Diat.,  p.  60.  Castracane,  Catalogo  di  Diat.  raccolte 
nella  Val.  Intrasca,  p.  15.  Clcve,  Om  Svendsa  ech  Korska  Diat., 
p.  219. 

Friarstown,  Piperstown,  Eillikee,  Co.  Dublin.  Glenohiee,  Greenane, 
Oo.  Wicklow.  Feighcullen,  Co.  Eildaxe.  (Moanarone^  Co.  Cork;  Wm. 
Sm.) 

Fragxlaria  aqudlu,  (Heiberg.)    Fresh  or  Brackish  water. 

Fnistiiles  considerably  longer  than  in  the  last  species ;  on  side  view 
linear ;  ends  attenuated  and  rounded ;  strise  fine,  persistent.  Heibeig's 
figure  represents  the  strise  as  interrupted  by  a  narrow  median  ^ace, 
but  in  the  forms  that  came  under  my  inspection  the  strie,  althoagh  at 
first  they  seemed  interrupted,  as  described  by  Heiberg,  on  closer  ex- 
amination were  obviously  persistent. 

Heiberg,  De  Danske  Diat.,  p.  61,  T.  iv.,  fig.  12.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  219. 

Oyster  beds,  Malahide,  Co.  Dublin. 


O'Mbara — Report  on  the  Irish  Diatomacece.  283 

mregtlaria  truunma,  N.  S.    Presh  water. 
^  Fnutoles  very  large;  on  side  view,  coiudderably  expanded  in  the 
imddle,  and  gradually  tapering  towards  the  rounded  ends ;  strisd  fine, 
persistent.     (PI.  27,  fig.  16.) 

AgMd,  Co.  Wicklow. 

J^ag%hr%»  erot&nemU^  (Kitten.)    Fresh  water. 

Prastnles  long ;  margins  on  front  view  slightly  waved ;  on  the  side 
view  narrow ;  very  slightly  expanded  in  the  middle,  and  gently  attenn- 
aled  towards  the  slightly  capitate  ends ;  striss  fine,  persistent. 

This  species  seems  widely  diffosed,  having  been  found  by  me  in 
gatherings  made  by  Mr.  Mozeley,  of  H.M.S.  Challenger,  at  Kergaelin's 

Pond,  Newcastle  Lyons,  Co.  Dublin.  HUl-pond,  Greenane,  near 
Kathdrum,  Co.  Wicklow.  Lough  Dei^g,  Co,  Qalway.  Bundoran,  Co. 
Donegal. 

Fragtlaria  tenuieoUis,  (Heib.)    Presh  water.' 

Pnutules  small ;  on  front  view  slightly  attenuated  at  the  ends ;  on 
side  view  narrow,  considerably  expanded  in  the  middle,  and  gently 
attenuated  towards  the  capitate,  rounded  ends ;  strin  fine,  penostent. 

Heiberg,  De  Danske  Diat.,  p.  62,  T.  v.,  fig.  18. 

MOl-pond,  Ghreenane,  near  Bathdrum,  Co.  Wicklow.  If  alahide,  Co: 
Dublin. 

liroffilaria  ttriaiula,  (Lyngb.)  •  Marine. 

Prustules  short ;  on  side  view  linear,  rounded  at  the  ends ;  strio 
extremely  fiLne,  persistent. 

Lyngbye,  Tent.Hydr.  Dan., p.  183,  T.  Ixiii.  Wm.  Sm.,B.D.,  Yol.ii., 
p.  28.  Cleve,  Om  Svenska  och  Norska  Diat.,  p.  219. — ^Fiagilaria  aurea, 
Grev.  Brit.  Plora,  p.  408.  Harvey's  Manual,  p.  197. — Grammoncma 
jurgenaii,  Agardh,  Consp.,  p.  68.  Balfs,  in  Piitch.,  p.  778,  PI.  xv., 
figs.  24, 25.  Bab.,  PI.  Eur.,  sect.  1,  p.  124.— -Gxammatonema  stratulunr, 
Kutz.    Sp.  Alg.,  p.  187. 

Salt  ditch,  Arklow,  Co.  Wicklow.  Ballybrack,  Monkstown, 
Kingstown,  Co.  Dublin.    Lame,  Bathlin  Island,  Co.  Antrim. 

lyagilaria  eonetruenSf  (Ehr.)    Presh  water. 

Prustules  short ;  on  side  view  groatly  expanded ;  ends  short  and 
attenuated ;  striee  fine,  persistent. 

Grunow,  Yerhand  der  K.  K.  Zool.  Bot.  Gescl.,  Band  xii.,  1862, 
p.  871.  Bab.,  PL  Eur.,  sect.  1,  p.  120. — Staurosira  construens,  Ehr. 
Mic,  T.  iii.  3,  fig.  8 ;  T.  iii.  1,  fig.  16 ;  T.  xxxix.  2,  fig.  10.  Balfs, 
in  Pritch.,  p.  791.   PI.  xv.,  fig.  5. — Odontidium  tabellana,  Wm.  Sm., 

X.  L  A.  FSOO.,  SBB.  n.,  VOX.,  n.,  SOXBVOl.  2  N 


284  Proceedings  of  the  Royal  IriA  Academy. 

B.D.,  Vol.  ii.,  p.  17.  PL  xxxiv.,  fig.  291  a.,  and  Fragflaria  undata, 
Snpp.  PI.  Ix.,  fig.  877  a. 

Piperstown,  Killikee,  Co.  Dublin.  Vemer's  Bridge,  Co.  Armagh, 
Float  bog,  Co.  Westmeath. 

Wm.  Smitb  has  described  a  form  as  Odontidium  parasiticnm,  some- 
times expanded  in  the  middle,  sometimes  constricted,  B.  D.,  Yol.  ii., 
p.  19,  Supp.  PI.  Ix.,  fig.  875.  The  separate  valves  of  the  latter  would 
seem  to  be  a  variety  (^  the  following  species,  those  of  the  former  to 
belong  to  the  present ;  the  habit  of  growth,  however,  is  much  more 
that  of  Synedra  than  of  Fragilaria.  Some  few  specimens  have  occa- 
sionally come  under  my  notice,  parasitic  on  Nitzschia  sigmoidea,  and  in 
no  way  differing  from  the  representation  in  Smith's  figure.  So  seldom, 
however,  did  they  occur,  and  in  such  small  quantity,  I  never  could 
make  any  satisfactory  examination  of  them,  and  therefore  refer  to 
the  subject  here  in  deference  to  the  opinions  of  the  best  authors,  who 
have  placed  them  in  the  genus  Fraguaria — ^not  because  I  agree  with 
them  in  considering  such  is  their  proper  place,  but  because  I  consider 
it  inexpedient  to  make  any  change  untU.  an  opportunity  for  more 
thorough  examination  shall  have  been  afforded. 

The  forms  have  occurred  in  gatherings  from  Bohemabreena  and 
Killikee,  Co.  Dublin. 

Fragtlaria  undata,  fWm.  Sm.)    Fresh  water. 
Yalves  broad  on  side  view ;  constricted  in  the  middle ;  ends  attenu- 
ated ;  striae  strong,  persistent. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  24,  Supp.  PI.  Ix.,  fig.  377.— Odonti- 


^umtabellaiia,  Wm.  Sm.,  B.D.^Vol.  ii.,  p.  17;  Pl.xxxiv.,  fig^291  a.— 

L  Pritch.,   p. 
virescens  var.  undata,  Grunow,  Verhand  der  £.  £.  Zool.  Bot.  Gesel., 


Fragilaria  constricta  in  part,  Balfs,  in  Piitch.,   p.  777. — ^Fragilaria 


Band  xii.,  1862,  p.  874.  Grunow  regards  this  form  as  likely  identical 
with  Fragilaria  constricta,  Ehr.  Mic,  T.  xvi.,  2,  figs.  84,  85 ;  as  also 
with  F.  binodis,  Ehr.  Mic,  T.  vi.  1,  fig.  48 ;  but  as  there  is  some 
doubt  on  this  point,  and  as  some  of  the  figures  of  the  forms  so  named 
appear  to  be  incorrectly  attributed  to  this  species,  it  is  better  to  refer 
the  species  to  Wm.  Smith,  whose  figure  admits  of  no  doubt. 

Bohemabreena,  Killikee,  Co.  Dublin. 

Fragilaria  tMsoUpta,  (Eab.)    Fresh  or  brackish  water. 

Frustules  on  front  view  regularly  quadrangular ;  on  side  view  narrow, 
constricted  at  the  middle,  and  more  slightly  constricted  towards  the 
apices,  which  are  narrowed,  produced,  and  sub-capitate ;  stri»  fine, 
persistent. 

fieiberg,  De  Danske  Diat.,  p.  61,  T.  iv.,  fig.  11. — ^Fragilaria  capu- 
cina  var.  mesolepta,  Eab.,  Fl.  Eur.,  sect.  1,  p.  118. 

Bock  pool  on  sea-shore,  Carrickf  ergus,  Co.  Antrim.  Malahide ; 
^asin,  Eingsend,  Co.  Dublin. 


O'Measa — Report  on  the  Irish  Diatomaeea.  285 

Genus  II.     DekticuuLi  Kiitz. 

Fnustules  united  in  parallel  filaments;  on  front  view  regularly  quad- 
rangular,  on  side  Tiew  narrow,  eUiptical,  costatey  costsB  not  pervious. 


Xiitzing's  distinetion  between  tliis  genus  and  Odontidium  is  not 
very  obvious.  Smith  entertains  considerable  doubt  as  to  the  propriety 
of  separating  them,  but  distinguishes  them  by  the  relative  length  of 
the  filaments.  Those  whose  fmstules  form  short  filaments,  he  attri- 
butes to  Denticula,  while  those  forming  filaments  of  considerable 
length  constitute  the  genus  Odontidium.  Half  s  retains  the  two  genera, 
interposing  that  of  Plagiogramma  between  them,  and  remarks  that,  in 
the  valves  of  Denticula,  fine  strise  are  interposed  between  the  cost®, 
this  peculiarity  not  being  noticeable  in  the  vidves  of  the  several  species 
of  Odontidium.  Babenhorst  also  retains  the  two  genera,  and  inter- 
poses the  genus  Gomphogramma  between  them,  his  distinguishing 
character  being  the  same  as  that  on  which  Smith  relies.  Grunow 
relegates  the  genus  Denticula  to  the  group  KitzschiesB,  separating 
from  it  Denticula  obtusa,  Kiitz.,  which  he  includes  under  Fragilariese; 
while  Heiberg,  who  appears  to  be  followed  by  Cleve,  drops  both 
genera,  referring  Odontidium  parasiticum,  Wm.  Sm.,  to  the  genus 
Eragilaria,  and  Odontidium  mutabiLe,  Wm.  Sm.,  to  the  genus  Dia- 
toma. 

The  distinctive  characters  of  the  genera,  as  here  defined,  rest  on 
the  fact  that,  in  Denticula,  the  costse  are  interrupted  by  a  broader  or 
narrower  intermediate  space,  while  the  cost®  in  Odontidium  are  per- 
vious. 

Dentteula  ohtusa,  (Kiitz.)    Fresh  water. 

Filamente  short ;  on  side  view  narrow ;  elliptical,  costsB  marginal, 
with  fine  pervious  strise  interposed. 

Kutz.  Bao.,  p.  44,  T.  xvii.,  fig.  14.  Rab.  Siissw.  Diat.,  p.  33,  T.  i., 
fig.  8.  Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  19,  PI.  xxxiv.,  fig.  292.  Balfs,  in 
Pritch.,  p.  773. 

Biver  Dodder,  Basin  of  Grand  Canal,  Co.  Dublin. 

Denticula  mutahilu,  (Wm.  Sm.)    Fresh  water. 

Frustules  varying  greatly  in  size,  generally  forming  long  filaments; 
on  side  view  nearly  oval,  and  sometimes  narrow,  elliptical ;  costaB 
broadly  marginal,  without  interstitial  strise.     (PI.  27,  fig.  17.) 

Odontidium  mutabile,  Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  17,  PI.  xxxiv., 
fig.  290.  Grunow,  Verhand  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii., 
1862,  p.  369.— Fragilaria  mutabilis,  Bab.  Fl.  Eur.,  sect.  1,  p.  118. 
Diatema  mutebUe,  Heiberg,  De  Danske  Diat.,  p.  58.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  219. — ^Dimeregramma  mutebUe,  Balfs,  in 
Priteh.,  p.  790. 

2N2 


286  Proceedings  of  the  Royal  Ir%$h  Academy. 

Smith,  with  doubtftdnesB,  refers  Diatoma  tenue,  Eiitz.  Bac.,  p.  48, 
T.  xviii.y  figs.  9y  10,  and  Odontidium  striolatuxxLy  Kiitz.  Bac,  p.  45, 
T.  xzi.,  fig.  20,  to  this  species;  and  Onmow,  under  Diatoma  tenue, 
Kiitz.,  remarks,  <*  I  do  not  find  this  variety  described  in  Wm.  Smith's 
Brit.  Diat.,"  Verhand  der  K.  K.  Zool.  Bot.,  Gesel.,  Band  xii.,  1862, 
p.  862.  As  so  much  doubt  rests  upon  the  forms  described  by  Eiitz- 
ing,  I  have  referred  the  species  to  Wm.  6m.,  whose  accurate  figure 
remoTes  all  doubt  as  to  the  identification  of  it. 

Lough  Moume  deposit.  Ditch  near  Giants'  Causeway,  Ballyleg, 
Co.  Antrim.  Derrylane  Lough,  Stream  near  Crossdoney,  Co.  Cavan. 
Lucan,  Bohemabreena,  Co.  Dublin.  Connemara,  Co.  Galway.  Black 
Castle,  Glenchree,  Co.  Wicklow.  Feighcullen,  Eoyal  Canal,  near  En- 
field, Co.  Kildare.  Tacumshane,  Co.  Wexfoid.  Eilleshin,  Queen's 
County. 

Oenus  in.     Odonhdiitk^  Kiitz. 

FrustuLeB  united  in  longer  or  shorter  parallel  filaments ;  on  front 
Tiaw  regularly  rectangular,  on  side  -view  elliptical,  coatate;  costse 
perrious;  their  ends  very  conspicuous  on  front  yiew.    . 


Odoniidium  Hnuatum^  (Wm.  Sm.)    Fresh  water. 

Prustules  united  in  short  filaments ;  on  side  riew  somewhat  lanceo- 
late ;  outline  sinuous ;  expanded  and  angular  in  the  middle ;  costte  rela- 
tiyely  fine. 

In  consequence  of  the  supposed  ezcentric  structure  of  the  frustulo 
of  this  species,  Grunow  has  transferred  the  genus  Denticula,  as  before 
stated,  to  the  group  Nitzschiese ;  and  Babenhorst,  taking  the  same  yiew 
of  the  structure  oi  the  frustule,  adopts  his  suggestion,  but  establishes 
a  special  genus,  Ghninowia,  for  its  reception,  a  course  in  which  he  is 
followed  by  Cleye.  This  treatment  appears  to  me  inadmissible,  inas- 
much.  as  tiie  frustules  are,  in  general  structure,  perfectly  symmetri- 
cal. In  some  specimens  the  striation  appears  on  one  side,  while  the 
opposite  side  seems  destitute  of  cost®.  This  may  be  an  illusory  appear- 
ance, arising  from  the  conyezity  of  the  yalye  when  yiewed  at  an  angle 
to  the  plane  of  the  field ;  but,  certainly,  it  is  by  no  means  uniyersal. 
By  accurate  adjustment  I  haye  traced  the  costsB  from  one  side  to 
the  other,  and  at  the  extremities,  where  the  conyexity  appears  less 
than  in  l^e  middle,  the  persistent  character  of  the  costte  is  easily 
traced. 

Denticula  sinuata,  Wm.  Sm.,  B.D.,  Yol.  ii.,  p.  21,  PI.  xxxiy., 
fig.  295.  Castracane,  Catalogo  di  Diat.  raccolte  nell  Yal  Intrasea,  p.  14. 
— ^Dimeregramma  sinuatum,  Ealfs,  in  Pritch.,  p.  730,  Fl.  iy.,  fig.  12. 

Eiyer  Dodder,  Co.  Dublin.  Slate  quarry,  Glanmore,  Co.  Wicklow. 
Lough  GiU,  Co.  Kerry. 


O^MxARA-^Beport  (m  the  Irkh  JHatcmaUcB.  287 

Odontidium  hyemaUy  (Lyhgb.)    Fresli  water. 

PnutoleB  in  long  filaments ;  Talye  on  side  view  nairow,  elliptical ; 
eostae  latrong,  abont  ten  in  number,  with  distinct  linear  stris  between 
the  costs ;  ends  of  costsB  on  front  yiew  forming  a  narrow  margin. 

Kiitz.  Bac,  p.  44,  T.  xviii.,  fig.  4.  Rab.  Siissw.  Diat.,  p.  34,  T.  ii., 
fig.  4.  Wm.  Sm.,  B.D.,  Yol.  ii.,  p.  15,  PI.  xxxiv.,  fig.  289.  Ralfs, 
in  Pritch.,  p.  775,  PI.  xiii.,  fig.  25.  Grunow,  Yerhand  der  K.  K.  Zool. 
£ot.  Gesel.,  Band  zii.,  1862,  p.  856. — ^Diatoma  hyemale,  Heiberg,  De 
Danske  Diat.,  p.  58.  Cleye,  Dm  Svenska  och  Norska  Diat.,  p.  219. 
— ^Fragilaria  hyemalis,  Lyngb.,  Tent.  Hydr.  Dan.,  p.  63. 

"Wet  rock,  Black  Castle,  Co.  Wicklow.  Streamlet  near  Belfast, 
Oo.  Antrim. 

Odontidium  mesodon,  (Ehr.)    Fresh  water. 

Pmstules  united  in  long  filaments,  shorter,  wider,  and  broader 
than  in  the  preceding  species ;  on  side  view  broadly  elliptical,  with 
three  to  five  strongly  developed  costaa,  which,  in  consequence  of  the 
greater  convexity  of  the  valve,  appear  longer  on  the  front  than  in  the 
foregoing  species ;  fine  strise  may  be  discovered  between  the  oostaa 
without  much  difficulty.     (PI.  27,  fig.  18.) 

Heiberg  attributes  the  species  to  Lvngbye,  Smith  to  Kiitzing ;  but 
as  Siitzing  himself  identifies  it  with  Fragilaria  mesodon  of  Ehr,  and 
the  Fragilaria  hyemalis  of  Lyngbye  is  regarded  by  the  same  writer  as 
identical  with  both  Odontidium  hyemale  and  0.  mesodon,  the  species 
may  properly  be  referred  to  Ehrenberg. 

Kutz.  Bac.,  p.  44,  T.  xvii.,  fig.  1.  Rab.  Sussw.  Diat.,  p.  34,  T.  ii., 
fig.  2.  IVm.  Sm.,  B.D.,  Vol.  ii.,  p.  16,  PI.  xxxiv.,  fig.  288.  Ralfs,  in 
Pfitch.,  p.  75. — Odontidium  hyemale  var.  mesodon,  Grunow,  Verhand 
der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  857.— Fragilaria 
mesodon,  Ehr.  Mic,  T.  ii.,  fig.  9. — ^Diatoma  hyemale,  Heib.,  De  Danske 
Diat.,  p.  58.  Cleve,  Om  Svenska  och  Norska  Diat.,  p.  219.  Both 
these  last  named  authors  regard  this  and  the  preceding  species  merely 
as  varieties. 

Friarstown,  Piperstown,  Co.  Dublin.  Glenchree,  Powerscourt, 
Co.  Wicklow.    Well  at  Farraghy,  Biver  Dour,  Co.  Cork. 

Odontidium  anomalum,  (Wm.  Sm.)    Fresh  water. 

Filaments  short ;  frustules  on  front  view  usually  exhibiting  ill- 
temal  cells,  likely  the  result  of  imperfect  self -division ;  on  side  view 
narrow,  linear,  sughtly  constricted  at  the  ends.  Costes  strong,  about 
eight  or  ten  in  number. 

Wm.  Sm^  B.D.,  Vol.  ii.,  p.  16,  Supp.  PI.  Ixi.,  fig.  376.  Ralfs,  in 
Pritch.,  p.  776.  Grunow,  Verhand  der  K.  K.  Zool.  Bot.  Gesel.,  Band 
xii.,  1862,  p.  357,  T.  iv.,  -fig.  4.     Rab.  Fl.  Eur.;  sect.  1,  p.  116. 

Ditdi  near  Newcastle,  Co.  "Wicklow.  This  form  is  usually  found 
in  Alpine  districts. 


288  Proceedings  of  the  Boyal  Irish  Academy. 

Odcntidium  tenue,  (Kiitz.)    Fresli  water. 

FrustuleB  united  in  short  filaments  ;  on  side  yiew  narrow,  ellipti- 
cal, with  sharp  ends ;  costss  numerous,  with  interrupted  linear  stris& 
interposed. 

Denticula  tenuis,  Eiitz.  Bac.,  p.  43,  T.  XTii.,  fig.  8.  Wm.  Sm., 
B.D.,  Vol.  ii.,  p.  20,  PL  xxxiv.,  fig.  293.  Ralfs,  in  Pritch.,  p.  773. 
Eab.  Fl.  Eur.,  sect.  1,  p.  114. 

Powerscourt,  Co.  Wicklow.    Eiver  Dour,  Co.  Cork. 

Odantidium  injlaium,  (Wm.  Sm.)    Fresh  water. 

Frustules  united  in  short  filaments ;  on  side  yiew  short,  broadlj 
elliptical,  costsB  close. 

Denticula  inflata,  Wm.  Sm.,  B.  D.,  Yol.  ii.,  p.  20,  PI.  xxxiv., 
fig.  294.  According  to  Ealfs,  =  Denticula  crassula,  Nagcli.  Ealfs> 
in  Pritch.,  p.  773.     Rah.  Fl.  Eur.,  sect.  1,  p.  115. 

River  Dour,  Co.  Cork. 

Odantidium  elegans^  (Kutz.)     Fresh  water. 

Frustules  united  in  short  filaments,  on  front  view  slightly  ellipti- 
cal; truncate,  with  large  glandular  expansions  at  the  ends  of  the 
coste ;  on  side  view,  narrow,  elliptical,  pointed  at  the  ends ;  cost© 
close. 

Denticula  elegans,  Ktitz.,  p.  44,  T.  xvii.,  fig.  5.  Eab.  Siissw. 
Diat.,  p.  33,  T.  i.,  fig.  4.  Ralfs,  in  Pritch.,  p.  773,  PL  xiii.,  fig.  4. 
Grunow,  Verhand  der  K.  K.  Zool.  Bot.  GeseL,  Band  xii.,  1862,  p.  549. 
Rab.  FL  Eur.,  sect.  1,  p.  115. — ^Denticula  ocellata,  Wm.  Sm.,  B.D., 
Vol.  ii.,  p.  20. 

Rocks,  Bundoran,  Co.  Donegal.  Powerscourt,  Rathdrum,  Co. 
Wicklow.  Rocks  near  the  sea  at  Black  Castle,  and  the  Silver  sanda 
in  the  neighbourhood  of  Wicklow.  Rocks,  Portrush,  Co.  Antrim. 
This  species  has  usually  been  found  by  me  on  moist  rocks. 

G^nus  rV.     DncEBEGBAHHA,  Ralfs. 

Frustules  in  short  filaments,  parallel  to  each  other.  On  the  front 
view  slightli^  constricted  near  the  ends ;  on  side  view  elliptical,  stri- 
ate ;  the  stnss  marginal. 


This  genus,  in  the  general  appearance  of  its  frustules,  bears  a  strong 
resemblance  to  some  of  the  forms  included  in  Odontidium  and  Denti- 
cula, to  which  latter  Gregory  assigned  the  numerous  forms  described 
b^  him,  but  may  be  distinguished  by  the  fact  that  the  margin  on  front 
view  presents  a  slight  constriction  at  the  ends. 


O'Measa — JRepart  on  the  Irish  Diatomacece.  289 

IHmeregrtmma  nanum,  {Qreg,)    Marine. 

Frustules  on  front  view  sliglitly  arched,  short,  but  broad ;  end  of 
striflB  appearing  at  the  margin ;  on  side  view  broadly  elliptical,  lanceo- 
late; marginal  BtrisB  long,  leaying  but  a  narrow  unstnated  median 
space. 

Ealffl,  in  Pritch.,  p.  790,  Plate  iv.,  fig.  38. — Dimeregramma 
Gregorianum,  Ghrunow,  Yerhand  der  K.  K.  Zool.  Bot.  Gesel.,  Band 
zii.,  1862,  p.  346.  This  last  named  author  changes  the  specific 
name  given  by  the  discoverer,  on  the  ground  that  the  original  designa- 
tion answers  only  for  the  smaller  forms,  the  species  varying  greatly  as 
regards  size.  Babenhorst  retains  the  original  specific  name  imposed 
by  Ghregory,  and  adopts  the  generic  name  Dimeregramma,  but  erro- 
neously ascribes  the  species  to  Pritchard.  Fl.  Eur.,  sect.  1,  p.  123. — 
Denticula  nana,  Gfregory,  Diat.  of  the  Clyde,  p.  23,  PL  x.,  fig.  34. 

Stomachs  of  Ascidians,  Belfast  Lough,  Co.  Antrim. 

Dimeregramma  minus,  (Greg.)    Marine. 

Prustules  on  front  view  as  in  the  preceding  species,  only  narrower 
for  the  length;  on  side  view  narrow,  elliptical,  and  pointed  at  the 
ends;  marginal  strise  long,  leaving  the  central  unstriate  band  very 
narrow. 

Ralfs,  in  Pritch.,  p.  790.  Grunow,  Yerhand  der  K.  K.  Zool.  Bot., 
Gesel.,  Band  xii.,  1862,  p.  376,  T.  iv.,  fig.  29.  Bab.  Fl.  Eur.,  sect. 
1,  p.  123,  who  attributes  this  species  as  well  as  the  preceding  to 
Pritchard. — Denticula  minor,  Gregory,  Diat.  of  Clyde,  p.  23,  PI.  x., 
fig.  35. 

On  piles  of  wooden  bridge,  Dollymount.  On  se&- weeds,  Ireland's 
Eye,  Co.  Dublin. 

Dimeregramma  dietans,  (Greg.)    Marine. 

Prustules  on  front  view  similar  in  outline  to  the  preceding  species; 
on  side  view  broadly  elliptical,  and  somewhat  lanceolate  at  the  ends ; 
marginal  strisB  costate,'short,  leaving  a  broad,  unstriate,  median  space. 
(PL  27,  fig.  19.) 

Ralfs,  in  Pritch.,  p.  790,  PL  iv.,  fig.  34.  Grunow,  Yerhand  der 
K  K.  ZooL  Bot.  Gesel.,  Band  xii.,  1862,  p.  376.  Bab.  Fl.  Eur., 
sect.  1,  p.  123. — ^Denticula  distans,  Gregory,  Diat.  of  Clyde,  p.  23,  PL 
z.,  fig.  36. 

Stomachs  of  Ascidians,  Belfast  Lough,  Co.  Antrim. 

Dimeregramma  marinum,  (Greg.)    Marine. 

Prustules  on  front  view  linear,  slightly  constricted  at  the  ends ;  on 
side  view  linear,  with  cuneate  ends,  and  slightly  expanded  in  the 
middle ;  strise  monilif  orm,  long,  leaving  the  median  unstriate  band 


2&d  Proceedings  qf  the  Eojfol  Irish  Academy. 

yery  narrow.    This  specieB  is  very  nmcli  larger  tkan  the  i^eoiee  here- 
tof  are  described. 

Ealfs,  in  Pritch.,  p.  790.  Bab.  El.  Eur.,  sect.  1,  p.  124.— Deittt- 
cnla  maiinay  Gregory,  Diat.  of  Clyde,  p.  24,  PI.  x.,  fig.  39. 

From  stomachs  of  Ascidians,  Bonndstone  Say,  Co.  Galwi^.  'Sea- 
weeds, near  the  NewtownlimaTady  junction,  Co.  Derry. 

OtexmB  y.    PtAGiOGiuLiacA,  Qrey. 

Fmstules  similar  to  those  of  the  preceding  genus,  from  whidh  tiioy 
ore  distinguished  by  the  presence  of  a  pair  of  strong,  transverse  costa, 
including  a  central  unstriate  band.  Some  of  the  species  have  also, 
besides,  a  similar  terminal  costa  at  either  end,  the  space  between 
which  and  the  apex  is  unstriate ;  yalves  striate,  except  at  the  central 
and  terminal  portions  referred  to ;  strisB  sometimes  interrupted  in  the 
middle,  sometimes  persistent ;  filaments  short. 


Flagiogramma  staurcphorum,  (Greg.)    Marine. 

Yalyes  furnished  with  a  central  pair  of  transverse,  pervious  oostBB; 
on  front  view  margin  slightly  dilated ;  on  side  view  eluptioal,  obtuse ; 
siadflB  fine,  monilif  orm,  persistent ;  central  eostse  inflexed ;  the  unstri- 
ate band  bounded  by  the  same,  narrow,  and  extending  across  the  valve, 
from  margin  to  margin. 

Heiberg,  De  Danske  Diat.,  p.  165.  Cleve,  Om  Svenska  och  Norska 
Diat.,  p.  219. — ^Denticula  staurophora,  Gregory,  Diat.  of  Clyde,  p.  24, 
PL  x.,  fig.  87.  Plagiogramma  Gregorianun,  Grev.,  Q.  J.  M.  B.,  July, 
1859,  p.  208,  PI.  X.,  figs.  1  and  2.  Ealfs,  in  Pritch.,  p.  774.  Bab. 
PL  Eur.,  sect.  1,  p.  117. 

On  piles  of  wooden  bridge,  Dollymount,  Oyster  beds,  Malahide, 
Co.  Dublin.  Sea-weeds,  near  Newtownlimavady  junction,  Co.  Derry. 
Sea-weeds,  Bannow,  Co.  Wexford.  Prom  stomachs  of  Asoidiana, 
Boundstone  Bay,  Co.  Galway. 

Plagiogramma  costatumf  (O'M.)    Marine. 

Yalves  furnished  with  both  a  central  pair  of  cost®  and  a  mngle 
costa  at  either  end ;  frustules  in  front  view  quadrangular ;  terminal 
constriction  slight ;  on  side  view  central  and  terminal  cost®  infiexed; 
valve  broadly  elliptical,  with  slightly-cuneate  ends ;  central  unstriate 
band  extending  across  the  valve ;  striae  costate :  costse  pervious.  (PI. 
27,  fig.  20.) 

O'Meara,  Q.  J.  M.  S.,  April,  1869,  p.  150,  PI.  xii.,  fig.  2. 

Arran  Islands,  Co.  Galway. 


O^ilRABA—IUpart  an  the  Irish  Diatomacem.  391 


Oenas  YI.    Diatoxa,  De  CandoUe. 

Frastules  tmited  in  zig-zag  filaments ;  strongly  costate ;  'c(9dtfl9  pier- 
Ti<ms. 


Gninow  states  tliat  tlie  yarious  species  of  this  genus,  as  well  bs 
those  of  Odontidium,  possess  fine  strisB  interposed  between  the  costiB, 
although  in  the  former  they  are  more  difficult  to  be  discovered  than  in 
the  latter.  The  most  careful  examination  of  the  valves  of  Diatoma, 
on  my  part,  has,  as  yet,  failed  to  bring  them  out. 

Dtatoma  vulgare,  (Bory.)    Fresh  water. 

Yalves  much  arched,  so  that  the  costss  present  a  deep  margin  on 
the  front  view ;  on  side  view  the  outline  is  elliptical,  sometimes  nar- 
rowed towards  the  ends ;  costse  strong  and  close. 

Kiitz.  Bac.,  p.  47,  T.  xvii.,  fig.  15,  1-4.  Bab.  Sussw.  Diat., 
p.  35,  T.  ii.,  fig.  6.  Wm.  8m.,  B.  D.,  Vol.  ii.,  p.  39,  PI.  xl.,  fig.  809. 
Ealfs,  in  Pritch.,  p.  778,  PI.  iv.,  fig.  13,  PI.  ix.,  fig.  168.  Grunow, 
Yerhand  der  K.  E.  Zool.  Bot.  GeseL,  Band  xii.,  1862,  p.  368.  Hei- 
berg,  De  Danske  Diat.,  p.  57.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  219.  Castracane,  Catalogo  di  Diat.  raccolte  nell  Yal  Intrasca, 
p.  15. 

Eaver  Dodder,  Grand  Canal  at  Portobello,  Co.  Dublin.  "Well, 
Strokestown,  Co.  Boscommon.  Stream  in  Glebe,  Delgany,  Co.  Wick- 
low.  Biver  Moy,  Poxford,  Co.  Mayo.  Stream,  KHle^bin,  Queen's 
Coimty.    Biver  Lee,  Co.  Cork. 

Diatoma  grande^  (Wm.  Sm.)    Fresh  water. 

Frustules  on  &ont  view  slightly  infiexed;  on  side  view  linear, 
slightly  constricted  towards  the  capitate  ends ;  costte  fine,  close.  (PL 
28,  fig.  1.) 

Wm.  Sm.;  B.  D.,  Yol.  ii.,  p.  39,  PL  xl.,  fig.  310.  Balfs,  in  Pritch., 
p.  779.  Heiberg,  De  Danske  Diat.,  p.  57.  Castracane,  Catalogo  di 
Diat.  raccolte  nell  Yal  Intrasca,  p.  15. — Diatoma  vulgare  var.  grando. 
Grunow,  Yerhand  der  K.  K.  Zool.  Bot.  GeseL,  xii.,  Band  1862,  p. 
364. — ^Diatoma  Ehrenbergii  forma  grandis,  Bab.  Fl.  Eur.,  sect.  1, 
p.  122.  Grunow  stands  alone  in  subordinating  this  form  to  Diatoma 
vulgare,  from  which  it  stands  distinguished  by  numerous  characters : 
so  distinct  is  it  from  that  species  in  the  outline  of  the  valve,  both  in 
front  and  side  view,  that  it  seems  deserving  of  occupying  the  place  of 
a  separate  species. 

Biver  at  Belleek,  Co.  Fermanagh.  Tacumshane,  Biver  Slaney, 
near  Sillnrin,  Co.  Wexford.  Biver  Shannon,  near  Athlone,  Co.  Bos- 
common. Lough  Corrib,  Co.  Mayo.  Lough  Derg,  Co.  Galway. 
Lough  Keagh,  Co.  Armagh.     Killikoe,  Biver  LifEey,  Co.  Dublin. 


292  Proceedings  of  the  Royai  Irish  Academy. 

Diatoma  elongatum,  (Agaidh.)    Fresh  water. 

FmstnleB  on  front  view  greatly  indexed ;  on  edde  yiew  linear,  nar- 
row, with  capitate  and  expanded  ends ;  yalves  not  so  much  arched  as  in 
the  preceding  species,  so  that  the  costse  appear,  on  front  yiew,  as  a  row 
of  puncta. 

There  is  considerable  diyersity  in  the  outline  of  yarious  forms  of 
this  species ;  in  some  the  capitate  ends  are  not  so  much  expanded  as  in 
others.  In  some  the  margin  on  side  yiew,  instead  of  being  perfectly 
straight,  is  slightly  expanded  towards  the  middle.  The  species  might, 
in  some  cases,  be  confounded  with  the  preceding ;  but  the  characters 
aboye  giyen  will  serye  to  distinguish  between  them. 

Agardh,  Syst.,  p.  4.  Ktitz.  Bac,  p.  48,  T.  xyiii.,  fig.  18.  Bab. 
Siissw.  Diat.,  p.  35,  T.  ii.,  fig.  1.  Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  40, 
PI.  xl.,  fig.  311.  Ralfs,  in  Pritch.,  p.  779,  PI.  iy.,  fig.  14,  PI.  ix., 
fig.  169.  Hciberg,  Be  Danske  Diat.,  p.  57.  Castracane,  Catalogo  di 
Diat.,  raccolte  nell  Val.  Intrasca,  p.  15.  CHeye,  Om  Syenska  och 
Norska  Diat.,  p.  219. — Diatoma  tenue  yar.  elongatum,  Grunow,  Ver- 
hand  der  K.  K.  Zool.  Bot.  Gcsel.,  Band  xii.,  1862,  p.  363. 

Dundrum,  Co.  Dublin.  Newcastle,  Co.  Wicklow.  (Cork  harbour. 
Belfast,  Wm.  Sm.) 

Diatoma  tmue,  (Kiitz.)     Freshwater. 

Frustules  small ;  on  front  yiew  regularly  quadrangular ;  ends  of  the 
costsB  appearing  like  a  fine  line  of  puncta ;  on  side  yiew  broadly  ellipti- 
cal ;  ends  rounded ;  costaa  fine. 

Smith  makes  this  species  a  yariety  of  Diatoma  elongatum.  Gru- 
now regards  it  as  the  representatiye  of  a  species  of  which  Diatoma 
elongatum  is  a  yariety.  A  careful  examination  of  the  form,  I  think» 
will  lead  to  the  conclusion  that  it  deserves  to  rank  as  a  distinct  species. 
In  general  appearance,  in  outline,  both  on  front  and  side  yiew,  it  differs 
from  Diatoma  elongatum ;  on  front  yiew  D.  elongatum  is  not  regularly 
quadrangular,  but  somewhat  infiexed  at  the  sides,  th^  ends  being 
broader  than  the  middle ;  whereas  in  D.  tenue,  the  front  yiew  nor- 
mally is  perfectly  quadrangular ;  on  the  side  yiew,  D.  elongatum  is 
more  or  less  distinctly  capitate,  the  ends  being  broader  than  the 
middle ;  the  sides  are  usually  straight  and  parallel ;  in  D.  tenue  the 
side  yiew  in  outline  is  broadly  elliptical;  the  ends  narrowed  and 
rounded.  For  these  reasons  I  consider  D.  tenue  is  obyiously  distinct 
from  D.  elongatum.  It  might  more  likely  be  considered  a  yariety  of 
Diatoma  yulgare,  but  its  features  are  perfectly  distinctiye.  The  yalye 
of  D.  yulgare  is  greatly  arched,  so  that  the  ends  of  the  costsB  occupy  a 
large  portion  of  the  front  yiew ;  whereas  in  D.  tenue,  the  yalye  is 
flat,  and  the  ends  of  the  costse,  on  the  front  yiew,  are  barely  noticeable. 

Kiitz.  Bac,  p.  48,  T.  xyii.,  fig.  9,  10.  Rab.  Sussw.  Diat.,  p.  35, 
T.  ii.,  fig.  5.  Ralfs,  in  Pritch.,  p.  779.  Grunow,  Verhand  der  K.  K. 
Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  362. — ^Diatoma  elongatum,  yariety 
y.     Wm.  Sm.,  B.  D.,  Yol.  ii.,  p.  40,  PI.  xH.  fig.  311  y. 


O'Meaba — Report  on  the  Irish  Diatomacece,  293 

Found  abundantly  in  a  gatheiing  from  salt  water  at  Howth,  in 
irhich  fresli  and  marine  forms  were  mingled,  the  latter  greatly  pre- 
dominating. Some  cnneate  forms  occurred  along  with  those  in  a 
normal  state,  just  as  described  in  Smith's  figure ;  but  the  former  are 
obyiously  to  be  regarded  as  monstrosities. 

Genus  VII.    Ealfsia,  K..G. 

As  Diatoma,  differing  only  in  this  respect,  that  the  yalyes  are 
hyaline,  and  without  costse. 


Balfna  hyalina,  (Kutz.)    Marine. 

Valves  on  front  view  quadrangular ;  on  side  view  narrow,  nearly 
linear,  narrowed  at  ends. 

Diatoma  hyalinum,  Kiitz.  Bac.,  p.  47,  T.  xvii.,  fig.  20.  Vm.  Sm., 
B.  D.,  Yol.  ii.,  p.  41,  PI.  xli.,  fig.  312.  Kalfs,  in  Pritch.,  p.  778,  PI. 
iv.,  fig.  16.  Bab.  Fl.  Eur.,  sect.  l,p.  122. — ^Fragilaria  hyalina  major, 
Grunow,  Verhand  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  p.  374. — 
Fragilaria  tenerrima,  Heiberg,  De  Danske  Diat.,  p.  63.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  220. 

Salt  ditch,  Breaches  near  Newcastle,  Co.  Wicklow.  Sea-weeds, 
Tramore,  Co.  Waterford. 

Ralfiia  minima,  (Balfs.)    Marine. 

Frustules  very  small ;  on  front  view  quadrangular ;  on  side  view 
broadly  elliptical. 

Diatoma  minimum,  "Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  41,  PI.  xli.,  fig.  313. 
Ralfs,  in  Pritch.,  p.  778. — ^Diatoma  hyalinum,  var.  minimum,  Bab. 
Fl.  Eur.,  sect.  1,  p.  123., — ^Fragilaria  minima,  Grunow,  Verhand  der 
K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  347. — ^Fragilaria  tenerrima, 
Heiberg,  De  Danske  Diat.,  p.  63.  Cleve,  Om  Svenska  och  Norska 
Diat.,  p.  220. 

Found  by  Ralfs  attached  to  Surirella  gemma,  but  found  by  me 
in  a  brackish  ditch,  Kilkee,  Co.  Clare,  in  which  no  specimen  of  Suri- 
rella genmia  appeared. 

Ralfsia  tahellaria,  N.  S.     Marine. 

Frustules  very  long,  '0038 ;  on  front  view  regularly  quadrangular; 
on  side  view  capitate  at  the  ends ;  gently  decreasing  in  breadth,  and 
then  gradually  expanding  towards  the  middle.     (PI.  28,  fig.  2. ) 

Sea-weeds,  Tramore,  Co.  Waterford.  Lough  Strangford,  Co. 
Down. 


284  .  Proceedings  of  the  Ea^al  Irkh  Academy. 

Geniis  YUt.    ^BvAPHomEn,  TSSst. 

The  characters  on  which  this  genus  is  grounded  are  : — ^First.  Tho 
symmetry  of  the  frustules  hy  which  they  are  separated  from  Cocconeis, 
which  some  of  the  species  in  other  respects  closely  resemble.  Secondly. 
They  do  not  form  parallel  filaments,  hy  which  circumstance  they  are 
distmgnished  from  those  of  Denticula  and  Dimeregramma.  Thirdly. 
The  striiB  are  interrupted  by  the  interposition  of  an  unstriate  longi- 
tudinal bandy  more  or  less  broad — a  feature  by  which  the  forms  of  the 
genus  may  be  discriminated  from  those  of  Diatoma  and  Odontidium. 


While  adopting  this  genus,  I  do  so  with  somewhat  of  the  feeling 
which  Grunow  has  so  well  expressed  in  the  following  remarks: — 
"The  genus  Bhaphoneis,  which  here  I  represent  in  Ehrenberg's 
(iiense  of  it,  is  widely  separated  therefrom,  for  the  purpose  of  receiving 
forms  which,  in  pomt  of  fact,  have  but  little  generic  relationship  to 
each  other.  Meanwhile,  it  is  nevertheless  a  sort  of  refuge  for  various 
Diatoms  which  have  not  been  thoroughly  investigated,  and  which, 
in  some  cases,  are  known  only  so  far  as  their  side  view  is  concerned. 
A  portion  of  these,  upon  more  mature  knowledge,  may  be  transferred  to 
Dimeregramma,  while  others,  from  their  Cocconeis-like  habit,  must  cer- 
tainly be  constituted  as  a  special  genus.  Yery  numerous  instances 
of  forms  belonging  to  the  latter  class  have  come  under  my  notice ; 
and  I  am  convinced  that  they  do  not  imderlie  the  upper  valves  of 
Cocconeis — and  for  this  reason,  that  I  have  never  found  associated  with 
them  valves  of  Cocconeis  with  a  central  nodule,  or  valves  which  in. 
other  details  of  structure  would  be  supposed  to  correspond  with  them." 
Yerhand  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  378.  Two 
of  the  forms  herein  included — ^namely,  Bhaphoneis  amphiceros  and 
Shaphoneis  rhombus,  Smith  has  placed  side  by  side,  under  the  same 
generic  name,  with  Doryphora  Boeckii,  with  which,  beyond  the  fact 
of  being  stipitate,  they  have  little  in  common.  Bhaphoneis  amphi- 
ceros was  observed  by  Kiitzing  in  situ,  and  described  and  figured  by 
him  as  stipitate.  I  am  not  aware  whether,  in  the  case  of  the  other 
forms  included,  a  similar  fact  has  been  noticed.  Whatever  presump- 
tion there  may  be  in  favour  of  the  supposition,  this  feature  cannot  be 
as  yet  admitted  as  a  general  characteriiBtic  of  the  group.  Odontidium 
Harrisoni,  Wm.  Sm.,  the  frustules  of  which  in  general  structure  are 
similar  to  those  of  Denticula,  as  I  have  defined  that  genus,  exhibits 
nevertheless  a  different  habit  of  growth,  the  frustules  being  attached 
by  a  cushion  or  short  stipes,  and  forming  a  filament,  the  several  frus- 
tules adhering  by  their  ends  to  one  another.  It  seems  then  in  this 
respect,  as  well  as  in  the  interrupted  striation,  to  stand  in  close 
relationship  with  Bhaphoneis  amphiceros,  and  on  this  accoimt  I  include 
it  in  the  same  genus ;  not  indeed  because  I  feel  quite  satisfied  on  this 
point,  but  because,  all  things  eonsideted,  I  regud  this  most  suitable 
«B  a  provisional  arrangement. 


O^MBARAr-'Beport  an  t/ie  Irish  Diatatnacece.  295 

JRhaphoneU  amphieeroif  (Ehr.)    Marine. 

On  side  view  yalves  shorti  broadly  rhomboid;  very  slightly  pro- 
duced at  the  apces;  strias  large,  monQiform,  radiate;  median  free  apace 
linear,  and  yery  narrow,  so  much  so  as  to  be  sometimes  scaicdy  dis- 
cernible ;  frustules  stipitate.     (PL  28,  fig.  8.) 

Balls,  in  Pritch.,  p.  791,  PI.  xiv.,  fig.  21.  Bab.  Fl.  Eur.,  sect.  1, 
p.  126. — Doryphora  amphiceros,  Kiitz.  Bac.,  p.  74.,  T.  xzi.,  fig.  2. 
Wm.  Sm.,  B.  D.,  Vol.  i.,  PI.  xady.,  fig.  224.  Grunow,  Yerhand  der 
K:K.  Zool.  Bot.  GeseL.Band  zii.,  1862,  p.  884. 

From  mud  on  sea-shore,  Co.  Clare,  supplied  by  Professor  SuUiyan* 
On  Sea- weeds,  Co.  Clare.    On  Sea-weeds,  Co.  Donegal. 

Tar,  lepioe&ras,  (Ehr.)    Marine. 

Similar  in  all  respects  to  Bhaphoneis  amphiceros,  but  longer,  nar- 
rower, and  the  ends  produced  into  long  bealu. 
Bhaphoneis  leptoceros,  Balfs,  in  Pritch.,  p.  791. 

Sea-weeds,  Co.  Donegal ;  sea-weeds,  Co.  Clare. 

• 

Bhaphoneis  rhombus,  (Ehr.)    Marine. 

Yalves  narrow,  elliptical;  ends  rounded,  sthsB  fine;  moniliform; 
parallel  in  the  middle,  and  slightly  radiate  towards  the  ends ;  median 
unstriate  space  narrow,  linear  in  the  middle,  and  expanding  towards 
the  ends. 

Balfs,  in  il^tch,  p.  792.  Grunow,  Yerhand  der  K.  K.  Zool.  Bot. 
Oesel.,  Band  xii.,  1862,  p.  379,  T.  iv.,  fig.  36.  Boper,  Q.J.M.S., 
Trans.,  Yol.  ii.,  1854,  PL  vi.,  figs.  7-10. 

Concerning  this  form,  (hrmow,  as  above  cited,  makes  the  following 
noteworthy  remarks : — **  Bhaphoneis  rhombus  ought  to  be  considered 
as  the  type  of  the  genus  Bhaphoneis,  which  must  ever  stand,  though 
other  species  be  separated  as  not  belonging  to  it.  The  frustules  in 
contradistinction  to  Doryphora  occur  free,  as  I  consider  I  have  satisfied 
myself  to  be  the  case." 

Sea-weeds,  Dundalk,  Co.  Louth.  Piles  of  the  wooden  bridge, 
DoUymount,  Co.  Dublin.     Sea-weeds,  Co.  Donegal. 

A  smaller  variety  occurs  frequently  in  the  last  named  gathering, 
much  broader  for  the  length  than  the  ordinary  specimens,  but  in  other 
respects  so  similar  that  it  cannot  be  considered  even  a  variety. 

Rhaphmms  scuMloides,  (Qronow.)    Marine. 

Yalves  small,  on  front  view  broadly  elliptical,  rounded  at  the  ends, 
stirse  obscurely  monilif  orm,  nearly  parallel  at  the  middle,  and  slightly 
radiate  towards  the  ends;  median  Dree  space,  narrow,  elliptical.  (PL 
28,  fig.  4.) 

Grunow,  Yerhand  der  K.K.  ZooL  Bot.  Gesd.,  Band  xii.,  1862,  p. 
883,  T.  iv.,  fig.  34. 

Bea-weeds,  Co.  Donegal. 


296  Proceedings  of  the  Boyal  Irish  Ac4xdemy. 

Mhaphoneis  lorenziana,  (Granow.)    Harine. 

Yalves  considerably  la^er  than  the  last  named,  and  in  all  respects 
similar,  except  that  in  outline  the  yalyes  are  rhomboid. 

Ghrunow,  Yerhandi  der  K.  K.  Zool.  Bot.  GeseL,  Band  zii.,  1862,  p. 
381,  T.  iv.,  fig.  5. 

Piles  of  wooden  bridge,  DoUymonnt,  Co.  Dublin. 

JRhaphoneis  lihumicaf  (Gronow.)    Marine. 

Yalves  broadly  elliptical,  almost  circular ;  stiiss  large,  monilif orm, 
squarish,  distinct,  larger  at  the  middle,  and  decreasing  in  size  as  they 
approach  the  margin,  radiate ;  median  unstriate,  space  narrow,  ellipti- 
cal.    (PL  28,  fig.  5.) 

This  form  presents  very  much  the  appearance  of  a  Cocconeis,  in 
which  genus  I  would  have  provisionally  placed  it,  were  it  not  that 
Grunow,  who  first  discovered  it,  placed  it  here. 

Grunow,  Yerhand  der  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  383,  T. 
iv.,  fig.  6. 

Arran  Islands,  Co.  Galway. 

JRhaphoneis  Harrisoniiy  (Wm.  Sm.)    Fresh  water. 

Frustules  attached,  filamentous,  connected  by  their  ends ;  on  front 
view  quadrangular;  on  side  view  somewhat  cruciform ;  angles  roimded; 
striae  costate,  slightly  radiate ;  median  unstriate  space  narrow,  Unear. 

OdontidiumHarrisonii,  Wm.Sm.,  B.  D.,  Yol.  ii.,  p.  18,  Supp.  PI.  Ix., 
fig.  373. — ^Dimeregramma  Hanisonii,  Ralfs,  in  Pritch.,  p.  290,  PI.  viii., 
fig.  6. — ^Fragilaria  Harrisonii,  Bab.  Fl.  Eur.,  sect.  1,  p.  119. — ^Diatoma 
Harrisonii,  Cleve,  Om  Svenska  och  Norska  Diat.,  p.  219. 

Priarstown,  Killikee,  River  Dodder,  Bohemabreena,  Co.  Dublin. 
Eoyal  Canal,  near  Enfield,  Co.  Xildarc.  Portadown.  Yemer's 
Bridge,  Co.  Armagh. 

Genus  IX.     Stitebea,  Ehr. 

Frustules  long  and  narrow,  both  on  side  and  front  view ;  attached 
by  a  gelatinous  cushion,  or  by  a  longer  or  shorter  stipes. 

The  characteristics  of  this  genus  are  so  well  marked,  that  very  little 
difference  of  opinion  has  existed  from  the  first  as  to  the  grouping  of 
the  several  species,  although  the  relation  of  the  genus  to  other  genera 
has  been  very  differently  represented.  Kiitzing  includes  Synedra  in 
his  group  of  Surirellese,  in  which  besides  he  ranges  the  genera  Campylo- 
discus,  Surirella,  and  Bacillaria.  The  last  named  has,  indeed,  a  super- 
ficial resemblance  to  the  frustules  of  Synedra,  but,  in  consequence  of 
its  unsymmetrical  character,  has,  by  more  recent  authors,  been  trans- 


O'Meara — Report  an  the  Iriah  IHatomacece,  297 

f  erred  to  the  Kitzschieee ;  but  with  Campylodiscus  and  SurireUa,  Syne- 
dra  has  few  common  characteristics.  Balis,  while  he  adopts  this 
grouping  of  Kiitzing,  expresses  dissatisfaction  with  an  arrangement  so 
heterogeneous,  and  suggests  that,  with  more  propriety,  Synedra  should 
be  ranked  under  the  Fragilariese.  It  is  not  very  easy  to  ascertain 
precisely  what  Smith's  views  were  as  to  the  relations  of  Synedra ;  for 
while  in  the  plates  the  Synedrse  are  ranged  next  to  the  NitzschisB,  in 
the  text  they  are  interposed  between  Pleurosigma  and  Cocconema. 
Por  the  reason  already  specified,  the  Synedrs  and  NitzschisB  stand 
very  remote  from  one  another,  in  a  classification  based  on  the  sym- 
metrical or  unsymmetrical  structure  of  the  frustule.  And  on  the  same 
ground,  as  well  as  for  other  reasons,  I  cannot  consider  that  the  right 
position  of  Synedra  is  in  close  relation  either  with  Cocconema  or 
Pleurosigma.  Grunow,  either  led  by  the  suggestion  of  Ealf s,  or  by 
his  own  sagacity,  included  the  genus  in  the  first  sub-group  of  his 
group  DiatomeaB ;  and  although  some  genera  which,  for  reasons  spe- 
cified before,  ought  not  to  be  placed  in  this  connexion,  are  included 
in  the  sub-group,  still,  by  this  arragement,  the  genus  was  associated 
with  its  natural  allies.  Heiberg's  group  of  Fragilariese  is  nearly  identi- 
cal with  Gnmow^s  sub-group  of  Diatomese,  the  only  difierence  being, 
that  he  includes  in  it  the  genus  Meridion,  which,  in  consequence  of 
the  unsymmetrical  structure  of  its  frustules,  requires  a  difierent  collo- 
cation. With  the  exceptions  mentioned,  I  agree  with  Gbrunow  and 
Heiberg  as  to  the  true  relationship  of  Synedra ;  and  in  this  yiew  am 
sustained  by  the  judgment  of  Eabenhorst  also,  who,  though  in  his 
Siissw.  Dial,  he  places  the  Synedrse  between  the  Naviculeffi  and 
CuneataB,  in  his  more  recent  work,  "Mora  Europaea  Algarum,"  follows 
the  more  natural  grouping  of  Grunow  and  Heiberg.  The  frustules  of 
Ealfsia  tabellaria,  regard^  separately,  might  be  considered  to  belong 
to  the  Synedrse,  and  were,  indeed,  regarded  by  me  as  identical  with 
Synedra  gracilis  vera,  not  of  "W.  Smith,  but  of  Grunow,  Verhand  der 
K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  401,  T.  v.,  fig.  17,  which 
it  strongly  resembles,  until  I  had  seen  the  frustules  in  situ,  and  so  be- 
came convinced  of  my  mistake.  And  in  some  cases  it  is  difficult  to 
distinguish  between  the  separate  frustules  of  some  of  the  larger  forms 
of  Pragilaria,  and  some  species  of  Synedra.  I  would  specially  refer  to 
Pragilaria  ungeraria,  Grunow,  the  frustules  of  which,  when  detached, 
are  scarcely,  if  at  all,  distinguishable  from  those  of  the  form  described 
by  KlHzing  as  Synedra  amphirhynchus.  But  whatever  slight  con- 
fusion may  arise  in  such  cases,  attention  to  the  distinctive  character- 
istics of  the  genus  will  readily  remove  it. 

(a.)  Stria  pervious  ;  frustules  not  arcuate  on  side  view. 

Sffnedra  ehrystaUina,  (Lyngb.)    Marine. 

Yalve  very  long ;  slightly  expanded  at  the  centre  and  extremities ; 
.  jstrise  costate ;  cost®  coarse ;  an  intramarginal  longitudinal  line  appears 
on  both  sides  throughout  the  entire  length.     (PL  28,  fig.  6.) 


298  Proceedings  of  tlte  Boyal  Irish  Academy. 

Gnmow  describeB  the  stipeB  as  ahort,  and  occamonally  slightly 
branched.  Eiitzing  regaids  this  species  as  identical  with  Diatoma 
crystallimim  of  Agudh,  and  saggests,  with  a  note  of  doabtfalnesa,  that 
it  may  be  the  same  as  Echinella  f  ascionlata  of  Lyngbye.  Smith  c<m* 
ftrms  the  former  opinion,  and  that  on  the  inspection  of  authentio  spe* 
cimens.  Heiberg,  who  seems  to  have  had  the  opportunity  of  inspecting 
anthentio  specimens  of  Lyngbye'a  spedes,  consiaers  it  the  same  as  the 
present.  The  species  I  attribute  to  Lyngbye,  and  adopt  Agaidh'a 
name  to  obyiate  confusion  with  other  species  named  S.  fawdculata. 

Kiitz.  Bac.,  p.  69,  T.  xvi.,  fi^.  1.  Wm.  Sm.,  B.  D.,  Yol.  i.,  p.  74, 
PI.  xii.,  fig.  101.  Balfs,  in  Pntch.,  p.  789.  Grunow,  Yerhand  der 
K  K  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  407.  Heiberg,  De  Danske 
Diat.,  p.  64.  Bab.  El.  Eur.,  Act.  1,  p.  189.— Diatoma  chrystalli* 
num,  Agaidh  Consp.,  p.  52. — ^Echindla  &aciculata,  Lyngb.  Tent, 
fiydrophyt.  Dan.,  p.  210. 

On  sea-weeds,  Salthill,  Co.  Dublin.  From  stomachs  of  Ascidians^ 
Boundstone  Bay,  Co.  Ghdway.  On  sea-weeds,  near  Dundalk,  Go* 
Louth.    On  sea- weeds,  Belfast  Lough,  Co.  Antiim. 

SynedrafidffeM,  (Qreville.)    Marine. 

Sunilar  to  tiie  preceding  species,  with  which  it  is  often  associated^ 
but  may  be  distinguished  by  the  greater  delicacy  of  the  stiias.  The 
stipes  as  described  by  Kiitzing  is  long  and  branched.     (PI.  28,  fig.  7.) 

Wm.  Sm.,  B.  D.,  Yol.  i.,  p.  74,  PL  xii.,  fig.  103.  Balfs,  in 
Pritch.,  p.  789.  Gnmow,  Yerhand  der  K.  K.  Zool.  Bot.  Oesel.,  Band 
xii.,  1862,  p.  408.  Baben.  Fl.  Eur.,  sect.  1,  p.  140.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  220. — ^Lichmophora  fulgens,  Kiitz. 
Bac.,  p.  123,  T.  xiii.,  fig.  5.  Eiitzing  and  Smith  concur  in  the  iden- 
tification of  this  species  with  Exilaiia  fulgens,  Oreville,  who  has  a 
prior  claim  to  the  authorship  of  this  species. 

Salt  ditch  near  Wexford.  Bannow,  Co.  Wexford.  Sea-weediB> 
Halahide.  Stomachs  of  Pectens,  Dublin  Bay.  Dollymount,  Co.  Dublin. 
Stomachs  of  Ascidians,  Co.  Clare.  Sea^weeda,  Dundalk,  Go.  Loutlu 
Sea-weeds,  Belfast  Lough,  Co.  Antrim. 

Synedra  haetduSf  (Greg.)    Marine. 

Similar  to  preceding  species,  but  not  expanded  at  the  middle  or 
ends  as  it  is ;  striss  somewhat  coarser,  and  without  the  submarginal 
longitudinal  lines.     (PI.  28,  fig.  8.) 

Gregory,  Q.  J.  M.  S.  Trana.,  Yol.  v.,  1857,  p.  88,  PI.  L,  fitg.  54. 

Sea-weeds,  Co.  Clare.  Stomachs  of  Ascidians,  Boundstone  Bay> 
Co.  Galway. 


O^'KEAHA—Eeport  on  the  Irish  Diatomacece.  299 

Synedra  superha,  (Kiitz.)    Marine. 

i^stuloB  long  on  front  yiew,  quadrangular,  slightly  tapering  at 
the  ends;  on  side  view  tapering  slightly  from  the  middle  to  the 
broadly  rounded  ends ;  submarginal  longitudinal  lines  strongly  dere- 
loped;  striffi  linear,  coarse,  and  slightly  waved;  stipes  short.  (PI. 
28,  fig.  9.) 

Kutz.  Bac,,  p.  69,  T.  xv.,  fig.  13.  Wm.  Sm.,  B.D.,  Vol.  i.,  p. 
74,  PI.  xii.,  fig.  102.  Ealfs,  in  Pritch.,  p.  789.  Grunow,  Verhand. 
der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.  p.  406.  Ealfs,  in  Pritch.,  p. 
789.  Cleve,  Om  Svenska  och  Norska  Diat.,  p.  220.  Eab.  Fl. 
Eur.,  sect.  1,  p.  139. 

From  stomachs  of  Ascidians,  as  well  as  from  seaweeds,  Belfast 
Lough,  Co.  Antrim.  Seaweeds,  Eostreyor,  Co.  Down.  Seaweeds, 
near  Wexford.  Seaweeds,  Malahide,  Co.  Dublin.  Airan  Islands, 
Stomachs  of  Ascidians,  Eoundstone  Bay,  Co.  Galway. 

Synedra  amphieephala,  (Kiitz.)     Fresh  water. 

FruRtule  small  and  narrow,  length  '0018,  breadth  in  middle,  on 
side  view  -00016.  On  front  view  linear;  on  side  view  nearly  linear 
in  the  middle,  and  gradually  attenuated  towards  the  slightly  dilated 
apices;  striaB  very  fine.     (PI.  28,  fig.  10.) 

Grunow  places  this  species  in  association  with  those  in  which  the 
strise  are  interrupted  in  the  middle  by  a  longitudinal  sulcus,  but  in 
the  specimens  which  have  come  under  my  notice  the  striae  are  obvi- 
ously pervious. 

Kiitz.  Bac,  p.  64,  T.  iii.,  fig.  12.  Eab.  Siissw.  Diat.,  p.  63,  T. 
iv.,  fig.  28.  Ealfs,  in  Pritch.,  p.  787.  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  400,  T.  v.,  fig.  11.  Eab.  Fl. 
Eur.,  sect.  1,  p.  136. 

Feighcullen,  Co.  Kildare.  Kilcool,  Powerscourt,  Co.  Wicklow. 
Bantry,  Well  at  Farraghy,  Co.  Cork.     Tarbert,  Co.  Kerry. 

8ynedra  investienSf  (Wm.  Sm.)    Marine. 

Frustules  minute,  length  varying  from  "0005  to  0020 ;  on  front 
view  quadrangular,  on  side  view  narrow,  linear,  tapering  towards  the 
rounded  extremities;  strise  coarse  and  very  close.     (PI.  28,  fig.  11.) 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  98.  Ealfs,  in  Pritch,  p.  787.  Eab. 
Fl.  Eur.,  sect.  1,  p.  135.  The  last  named  author  places  this  spedes  in 
a  group  distinguished  by  the  fact  of  the  striss  being  interrupted  by  a 
median  free  space ;  but  in  a  slide  kindly  supplied  to  me  by  Major 
Crozier,  E.  E.,  and  described  as  part  of  the  original  gathering  of  Smith's 
Synopsis,  the  forms  answering  Smith's  description  have  strong  pervious 
(tee. 

Malahide.    Kingstown  Harbour.     Salthill,  Co.^Dublin. 

11. 1.  A.  PBOC.,  8EB.  n.,  VOL.  n.,  SCIBNCB.  2  O 


300  Proceedings  of  the  Boyai  Irish  Academy. 

Synedra  aeula,  (Kiitz.)    Fresh  water. 

Fraetules  long  and  very  narrow;  on  front  view  attenuated  at  the 
ends ;  on  side  view  narrow^  attenuated  towaida  the  ends,  whidi  are 
nsnally  expanded  very  slightlyy  but  frequently  acute.  (PL  28, 
fig.  12.) 

Eiitz.  Bac,  p.  65,  T.  ziy.,  fig.  20. — Synedra  delicatissima,  Wm. 
8m.,  B.  D.,  Vol.  i.,  p.  72,  PI.  xii.,  fig.  94,  who  represents  the  strin  as 
interrupted  in  the  middle  by  a  distinct  median  line  with  small  central 
nodule,  features  which  do  not  exist.  Ealfs,  in  Pritch,  p.  787.  Cas- 
tracane,  Catalogo  di  Diat.  raccoltenell  Yal.  Intrasca,  p.  10. — Synedra 
acus,  yar.  elongata,  Qrunow,  Yerhand.  der  £.  K.  Zool.  Bot.  Gesel., 
Band  xii.  1862,  p.  399. 

Tacumshane,  Co.  Wexford.  Stream,  Crossdoney,  Co.  Cavan. 
Friarstown,  Malahide,  Well  St.  Fenton's,  Sutton,  Co.  Dublin.  Hen* 
derson's  Well,  Aughnacloy,  Co.  Tyrone. 

Far.  tenui*8ima,  (Kiitz.)    Fresh  water. 

In  all  respects  like  the  typical  species,  except  that  it  is  smaller, 
and  much  less  attenuated  at  the  ends  on  side  view. 

Synedra  tenera,  Wm.  Sm.,  B.D.,  V(^.  ii.,  p.  98.  Balfs,  in 
Pritch.,  p.  717,  who  makes  the  form  described  by  Smith  under  this 
name  distinct  from  Synedra  tenuissima,  with  which  I  consider  it  is 
identical. — Synedra  acus,  Grunow,  Yerhand.  der  K.  K.  Zool.  Bot. 
Oesel.,  Band  xii.,  1862,  p.  898. 

"Lough  Alloa,  near  Blarney,  and  near  Xillaloe,  Co.  Cork,"  Wrti. 
8m.,  Bohemabreena,  Dundrum,  Boat  harbour,  Dolphin's  bam. 
Biver  Dodder,  St.  Fenton's  Well,  Sutton,  Stream,  Blackrock,  Co. 
Dublin.     Killeshin,  Queen's  County,  Donoghmore,  Co.  Tyrone. 

Synedra  gracilis,  (Xiitz.)    Marine. 

Frustules  small,  *0012  in  length;  on  front  view  attenuated 
towards  the  ends ;  on  side  view  narrow,  elliptical,  broader  in  the  middle, 
gradually  attenuated  towards  the  rounded  and  slightly-expanded  ends; 
stipes  short,  nearly  sessile;  the  frustules  being  few  and  radiating 
aUghtly.     (PI.  28,  fig.  13.) 

Kutz.  Bac.,  p.  64,  T.  iii.,  fig.  14,  T.  xiv.,  fig.  2  h,  T.  xv.,  fig.  8, 
1,  2,  5.  Kalfs,  in  Pritch.,  p.  786,  regards  this  form  of  Kiitzing  as  iden- 
tical with  that  so  named  by  Wm.  Smith,  B.  D.,  Yol.  i.,  p.  70,  PL  xi., 
fig.  86.  The  forms,  however,  arc  quite  distinct.  Grunow,  Yerhand. 
der  K.  K  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  401.  It  is  to  be  re- 
marked that  the  last-named  author  regards  this  species  and  Synedra 
barbatula,  KUtz.  Bac.,  p.  68,  T.  xv.,  fig.  10,  as  so  nearly  allied  that 
the  latter  is  to  be  regarded  merely  as  a  variety  of  the  former.  I  can- 
not adopt  this  view,  and  for  these  reasons :  first,  the  growth  of  the 
two  is  quite  distinct ;  the  frustules  in  Synedra  barbatula  are  attached 
in  tablets,  while  those  of  Synedra  gracilis  are  fewer  in  number,  and 


O'Meara — Report  on  the  Irkh  Diatoniacece.  301 

Bomewhat  radiately  arranged.  They  differ  as  respects  the  character 
-of  the  striation.  In  Synedra  barbatula  the  strise  are  easily  detected, 
«nd  are  divided  by  a  narrow,  longitudinal  sulcus ;  in  the  smaller  spe- 
cimens of  Synedjni  gracilis  the  stiiation  is  obscure,  but  in  the  larger 
forms  the  striaB  are  apparent  and  peirious. 

From  stomachs  of  Ascidians,  Eoundstone  Bay,  Co.  Galway.  From 
fieaweeds,  Drehidnamaud,  Co.  Kerry.  Seaweeds,  Salthill,  Co.  Dub- 
lin. Seaweeds,  Tramore,  Co.  Waterford.  Seaweeds,  Greenore,  Co. 
Louth. 

(b.)  IhtstulM  arcuate  on  tide  view,  atria  pervwue. 

Synedra  undulata,  (Bail.)    Marine. 

Frustules  very  long  and  narrow,  with  undulate  margins ;  expanded 
in  the  middle  and  towards  the  ends;  stiise  moniliform.  (PI.  28, 
fig.  14.) 

Gregory,  Diat.  of  Clyde,  p.  59,  PL  xiv.,  fig.  107.  "Wm.  8m.,  B.D., 
Vol.  ii.,  p.  97.  Ralfs,  in  Pritch.,  p.  786.  Grunow,  Verhand.  der  K.K. 
Zool.  Bot.  Gesel.,  Band  xii.,  p.  405,  T.  vi.,  fig.  1.  Cleve,  Om  Svenska 
och  Norska  Diat.,  p.  220.  Bab.  Fl.  Eur.,  sect.  1,  p.  130. — Toxarium 
undulatum,  Bailey,  Mic.  Obs.,  p.  15,  figs.  24,  25. 

Grunow  associates  this  species  with  forms  characterised  by  the 
fact  of  the  striae  being  interrupted  in  the  middle,  and  it  is  so  repre- 
sented in  the  figure  above  referred  to ;  but  I  have  ever  found  the 
atrias  pervious,  as  in  Gregory's  figure.* 

Stomachs  of  Ascidians,  Co.  Clare.  Stomachs  of  Ascidiaus,  B^und- 
stone  Bay,  Co.  Gralway.  Stomachs  of  Ascidians,  and  also  from  sea- 
weeds, in  great  abundance,  Belfast  Lough,  Co.  Antrim. 

Synedra  lunaris,  (Ehr.)    Fresh  water. 

Frustules  on  front  view  quadrangular ;  on  side  view  arcuate,  at- 
tenuated towards  the  extremities;  striae  linear,  fine,  but  distinct;  stipes 
short.     (PI.  28,  fig.  15.) 

Ehr.  Infus.,  T.  xviii.,  fig.  4.  Kutz.  Bac,  p.  65,  T.  iii.,  fig.  11. 
Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  69,  PL  xi.,  fig.  82.  Kab.  Siissw.  Diat., 
p.  54,  T.  v.,  fig.  6.  Balfs,  in  Pritch.,  p.  185.  Grunow,  Verhand.  der 
K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  389.  Heiberg,  De  Danske 
Diat.,  p.  65.  Eab.  Fl.  Eur.,  sect.  1,  p.  128.  Cleve,  Om  Svenska  och 
Norska  Diat.,  p.  220.  Castracane,  Catalogo  di  Diat.  raccolte  nell  Val 
Intrasca,  p.  10. 

Lucan,  Co.  Dublin.  Glenchree,  Glenmalure,  Co.  Wicklow. 
Derrylane  Lough,  Co.  Cavan.  Bellarena,  Co.  Londonderry.  Five- 
nuletown,  Lisnaskea,  Co.  Fermanagh.  Pool,  Glencar,  Drumoughty 
Lough,  near  Eenmare,  Co.  Kerry.  Bantry,  Co.  Cork.  Connemara, 
Co.  Galway. 

202 


302  Proceedings  of  the  Boyal  Irish  Academy. 

8ynedra  hieeps,  (Kiitz.)     Freshwater. 

PhiBtaleB  comdderably  larger  than  those  of  the  last  species ;  on 
front  view  quadrangular ;  on  side  riew  arcuate ;  extremities  capitate. 
(PL  28,  fig.  16.) 

Kiitz.  Bac.,  p.  66,  T.  xiv.,  figs.  18  and  21.  Wm.  Sm.,  B.  D.,  Vol. 
i.,  p.  69,  PI.  xi.,  fig.  83.  Bab.  Siissw.  Diat.,  p.  55,  T.  v.,  fig.  9. 
Italfs,  in  Pritch.,  p.  786.  Heiberg,  De  Danske  Diat.,  p.  65. — 
Synedra  flezuosa  ?  Castracane,  Catalogo  di  Diat.  raccolte  nell  Yal 
Intrasca,  p.  10.  Bab.  Fl.  Eur.,  sect.  1,  p.  129. — Synedra flexuosa,  rar. 
biceps,  Grunow,  Verhand.  der  K.  K.  -Zool.  Bot.,  Oesel.  Band  adi.^ 
1862,  p.  390. 

Killikee,  Co.  Dublin.  Carrickmacrillj,  Co.  Wicklow.  Glencar, 
Co.  Kerry.     Connemara,  Co.  Galway.     Bantry,  Co.  Cork. 

(c.)  Stria  pert iottii,  except  in  the  Middle,  where  there  is  a  free  space ^ 
hounded  hy  a  mare  or  less  perfectly  developed  ring. 

The  number  of  forms  legitimately  included  in  this  sub-diyision  is 
very  limited,  and  still  there  is  none,  perhaps,  in  which  greater  con- 
fusion reigns.  Smith  includes  the  four  foUowing  species  :  Synedra 
pulchella,  Kiitz.,  fresh  water;  S.  gracilis,  Kiitz.,  brackish  water;  S. 
acicularis,  Wm.  Sm.,  which  he  makes  »  8.  Isyis,  Kiitz,  brackish 
water;  and  S.  minutissima,  Kutz.,  fresh  water.  The  same  author  ex- 
cludes from  this  sub-division  S.  fasciculata,  which  seems  really  to 
belong  to  it,  judging  from  the  description  given,  as  well  as  from  the 
figure. 

To  look  at  the  figures  of  these  several  species,  it  might  be  ima- 
gined there  would  no  difficulty  in  distinguishing  the  one  from  the 
other ;  but,  practically,  the  difficulty  of  determining  is  found  to  be 
considerable.  Kiitzing's  figures  of  them  are  too  vague,  and  his  de- 
scriptions too  indefinite,  to  help  the  student  out  of  the  difficulty. 

Grunow  regards  Syn.  fasciculata,  Kiitz.,  a8=  Syn.  Saxonica  of  the 
same  author  and  Syn.  gracilis,  Kiitz.,  in  Wm.  Sm.,  B.  D.  Syn. 
parvula,  Kiitz.,  he  regards  as  =  Syn.  fasciculata,  Kiitz.,  Wm.  Sm.,  B.  D. ; 
and  Syn.  vaucherise,  Kutz.,  as  =  Syn.  minutissima,  Kiitz.,  in  Wm.  Sm., 
B.  D.,  as  well  as  to  Syn.  vaucheri»,  Kiitz.,  in  Wm.  Sm.,  B.  D.  The 
habitat  to  which  these  forms  have  been  respectively  assigned  will  fur- 
nish no  satisfactory  distinction.  Some  are  attributed  to  fresh  water, 
some  to  brackish;  but  when  forms  are  ascribed  to  the  latter,  it  is  diffi- 
cult to  ascertain  whether  they  are  fresh  water  forms  which  have  been 
carried  down,  or  marine  forms  which  have  been  carried  up,  or  forma 
incidental  to  brackish  water.  Grunow  has  found  Syn.  fasciculata  in 
salt  water  as  well  as  in  brackish,  and  likewise  in  the  Franzensbad 
deposit,  which  is  a  fresh  water  deposit,  and  in  which  I  have  alsa 
found  the  form  so  named  by  that  author ;  from  this  last  fact,  I  con- 
clude that  the  form  is  essentially  a  fresh  water  one,  and  not  thereforo 


O'Meara — Report  on  the  Irish  Diataniacece.  303 

to  be  discriminated  on  the  ground  of  habitat  from  Syn.  pnlchella. 
Speaking  of  this  last  named  form,  Grunow  sagaciously  remarks, 
"Whether  this  species  is  actually  distinct  from  the  preceding  (Syn. 
fasciculata,  Grun.  =  to  Syn.  gracilis,  Wm.  Sm.),  admits  of  considerable 
doubt.  Single  frustules  are  not  distinguishable.  The  separation  is 
founded  only  on  the  union  in  larger  fans  upon  a  stipes  often  tolerably 
thick,  which  is  by  no  means  constant,  and  the  occurrence  in  fresh 
vater."  Yerhand  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862, 
p.  392.  I  am  disposed  to  regard  all  these  various  forms  as  merely 
varieties  of  Syn.  pulchella — ^and  for  this  reason,  that  I  have  noticed 
them  more  or  less  mixed  together  in  gatherings  from  fresh  water 
localities,  as  well  as  in  places  where  the  water  was  slightly  brackish, 
4ind  almost  always  exhibiting  features  of  mutual  relationship. 

Synedra  pulchella,  (Kiitz.)    Fresh  water. 

On  front  view  linear,  slightly  attenuated  towards  the  ends;  on 
side  view  narrow,  lanceolate,  slightly  capitate;  the  mediaa  ring 
strongly  marked.     (PI.  28,  fig.  17.) 

I  have  never  seen  the  median  ring  so  round  or  so  decided  in  its 
•character  as  appears  in  Smith's  figure  of  the  species. 

Kiitz.  Bac.,  p.  68,  T.  xxix.,  fig.  87.  Wm.  Sm.,  B.  D.,  Vol.  L, 
p.  70,  PI.  xi.,  fig.  84,  Supp.,  PI.  XXX.,  fig.  84.  Rab.  Siissw.  Diat., 
p.  56,  T.iv.,  fig.  17.  Rails,  in  Pritch.,  p.  786.  Grunow,  Verhand.  der 
K.  K.  Zool.  Bot.  Gdsel.,  Band  xii.,  1872,  p.  392.  Heiberg,  De  Danske 
Diat.,  p.  65,  who  considers  it  a  brackish  water  form. 

River  Erne,  Crossdoney,  Co.  Cavan.  Caum  Ix)ugh,  near  Tralcc. 
Pedler's  Lake,  Dingle,  Co.  Kerry.  Kilcool,  Co.  Wicklow.  Stream, 
Pintragh,  Co.  Donegal. 

Var.  ffraetlis,  (Wm.  Sm.)     Fresh  water. 

This  variety  differs  from  the  preceding  only  in  not  being  con- 
stricted at  the  ends,  and  the  stipes  being  short,  the  frustules  scattered 
xmd  not  airanged  in  the  form  of  a  fan.  In  identifying  this  species  wc 
<jan  go  no  further  back  than  the  date  of  Smith's  work,  in  which  it  is 
faithfully  delineated.  Kiitzing's  figures  of  the  species  named  Syn. 
gracilis  arc  so  indistinct  that  it  would  be  impossible  to  identify  them 
with  certainty.     (PI.  28,  fig.  18.) 

Synedra  gracilis,  Wm.  Sm.,  B.  D,,  Yol.  i.,  p.  70,  PI.  xi.,  fig.  85. 
Ralfs,  in  Pritch.,  p.  786,  who  describes  the  form  as  marine.  Rab. 
Fl.  Eur.,  sect.  1,  p.  132,  where  the  form  is  stated  to  be  submarine,  in 
which  the  author  coincides  with  Smith. — Synedra  fasciculata,  Kiitz. 
— Synedra  saxonica,  Kiitz,  according  to  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesel.,  Band  xii.,  p.  391.  Cleve  regards  this  species  as 
incidental  to  brackish  water,  and  with  Grunow  considers  it  identical 
with  Synedra  fasciculata,  Kiitz,  Om  Svenska  och  l^orskaDiat.,  p.  220. 

Stream,  Port-na-Crush,  Co.    Donegal.     Camlough,  Co.    Antrim. 


304  Proceedings  of  the  Royal  Irish  Academy. 

Breaches,  near  Newcastle.      On  moist  rock,  Black  Castle,  Co.  Wick- 
low.    Tacnmshane,  Co.  Wexford. 

Var,  aeicularis,  (Wm.  Sm.)    Freeh  water. 

Besembling  Synedra  pnlchella,  only  longer  and  narrower.  (PL 
28,  fig.  19.) 

Wm.  8m.,  B.  D.,  Vol.  i.,  p.  70,  PI.  xi.,  fig.  86,  who  regards  it  as 
a  brackish  water  form. — Synedra  Iffivis,  Kiitz.  Bac.,  p.  65,  T.  xy., 
fig.  8.  2.  3.  4.  Were  this  the  case,  the  Tariety  shonld  be  attributed 
to  Kiitzing,  and  be  called  yar.  leYis;  but  Kiitzing's  figure  is  not 
sufficiently  distinct  to  enable  me  to  identify  the  Tariety  with  it,  and 
therefore  I  deem  it  better  to  retain  the  name  given  by  Smith,  who 
figures  it  with  accuracy. — Synedra  Smithii,  Ralfs,  in  Pritch.,  p.  786. 
G&unow,  Verhand.  der  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  392,  who- 
remarks,  **that  it  is  probably  only  a  very  long  variety  of  (what  he 
calls)  Synedra  fascicxdata,  mixed  up  with  which  he  found  it  upon 
Cladophora  flavida,  Kiitz.,  on  the  Peene  at  Woolgart,  and  in  such 
manner  that  no  dear  distinction  existed  between  the  two."  Bab.  FL 
Eur.,  sect.  1,  p.  131. 

Kiver  Slaney,  KiUurin,  Co.  Wexford.  Lough  Gill,  Co.  Kerry.. 
Carrickhugh,  Co.  Derry.  Kilcool,  moist  rock.  Black  Castle,  Co. 
Wicklow.  In  the  last  named  locality,  in  which  this  form  was  found 
abundantly,  marine  influence  was  scarcely  possible. 

Var.  laneeolata,  (Wm.  Sm.)    Fresh  water. 

Besembling  the  typical  form,  but  shorter  and  broader  in  proportion.. 
(PI.  28,  fig.  20.) 

Synedra  minutissima,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  70,  PL  xi.> 
fig.  87,  who  ascribes  the  species  to  Kutzing,  but  the  form  so  called  by 
the  last  named  author,  Bac.,  p.  63,  T.  iii.,  fig.  30,  can  scarcely  be^ 
identical  with  it.  More  likely  it  is  the  same  as  that  which  Kutzing 
describes  as  Synedra  lanceolata :  but  whether  or  not  this  be  the  case, 
the  designation  is  adopted  because  of  its  appropriateness,  and  the 
i^ecies  attributed  to  Wm.  Smith,  whose  figure  admits  of  no  mistake. 
Balfs,  in  Pritch.,  p.  786.  Heiberg,  De  Danske  Diat.,  p.  65,  who* 
attributes  the  form  to  fresh  or  brackish  water.  Bab.  Fl.  Eur.,  sect. 
1,  p.  139. — Synedra  vaucherie,  Grunow,  who  adopts  this  view  with 
doubtfulness,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862, 
p.  393,  T.  v.,  fig.  9.  This  last  named  author  regards  Synedra  vaucherise^ 
Ktitz.,  as  distinct  from  the  form  so  named  by  Wm.  Sm.,  and  the 
former  identical  with  that  figured  as  Synedra  minutissima,  by  Wm. 
Smith. 

River  Slaney,  Killurin,  Co.  Wexford.  River  at  Port-na-Crush,, 
and  stream,  Fintragh,  Co.  Donegal.  Stream,  Howth,  Co.  Dublin.. 
Stream  near  Giants'  Causeway,  Co.  Antrim.  Kilcool,  Black  Castle^ 
Co.  Wicklow. 


O'Meara — Report  on  the  Irish  Diatomacece.  305 

Tar,  linearis,  (Wm.  Sm.)    Fresh  water. 

Smaller  than  the  preceding  Tar.,  and  on  side  view  somewhat 
linear.     (PL  28,  fig.  21.) 

Synedra  fascicnlata,  Wm.  8m.,  B.D.,  Vol.  i.,  p.  73,  PI.  xi.,  fig, 
100,  who  has  inaccurately  confounded  this  fresh  water  species  with 
Synedra  fascicnlata,  Kiitz.  Bac,  p.  68,  T.  xt.,  fig.  5,  which  is  clearly 
8  marine  species. — Synedra  parvnla,  Kiitz.,  according  to  Ghrunow, 
Verhand.  der  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  392,  T.  It.,  fig.  17, 
where  the  form  is  accurately  figured ;  hut  as  it  is  impossihle  to  identify 
it  with  Kiitzing's  figure  of  the  species  so  named,  I  consider  it  more 
conduciye  to  accuracy  to  refer  this  species  to  Smith,  who  has  so  accu- 
rately descrihed  it;  and  as  his  specific  name  must  he  ahandonedfor  the 
reason  given,  and  that  adopted  hy  Grunow  is  not  quite  certain,  I  have 
given  it  a  name  characteriistic  of  its  general  appearance.  It  is  to  he 
noted  that  Smith  separates  this  form  from  those  with  which  it  stands 
related ;  hut  Grunow  and  Eahenhorst  coincide  with  me  as  to  its  inti- 
mate relation  to  the  group  of  which  Synedra  pulchella  is  the  type. 

Tacumshane,  Co.  Wexford.  Tide  pool,  Malahide.  In  hoth  which 
marine  and  fresh  water  forms  were  mixed  up,  hut  I  found  it  likewise 
mixed  with  the  preceding  variety  on  the  surface  of  wet  rooks  at 
Black  Castle,  Co.  Wicklow. 

(d.)  Stria  interrupted  hy  a  narrow  lanyitudtnal  sulcus;  valves 
linear. 

Synedra  capitata,  (Ehr.)    Presh  water. 

Frustule  on  front  view  linear,  expanded  slightly  at  the  ends ;  on 
dde  view  linear,  with  expanded  triangular  head.  (PI.  28,  fig.  22.) 
'  Ehr.  Infus.  T.  xxi.,  fig.  29.  Kiitz.  Bac.,  p.  67,  T.  xiv.,  fig.  19. 
Wm.  8m..  B.D.,  Vol.  i.,  p.  72,  PI.  xii.,  fig.  94.  Rah.  Siissw.  Biat., 
p\  55,  T.  iv.,  fig.  6.  Ralfs,  in  Pritch.,  p.  788,  PL  iv.,  fig.  29,  and  x., 
fig.  185.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii., 
1-862,  p-.  394.  Heiherg,  De  Danske  Diat.  p.  65.  Cleve,  Om  Svenska 
ofch  Norska  Diat.,  p.  220. 

In  Smith's  figure  there  appears  a  short  median  line  terminating 
towards  the  centre  in  small  pear-shaped  nodules,  and  also  a  centrid 
free  space;  the  same  features  appear  in  the  figure  of  Ealfs,  in  Pritchard, 
but  these  peculiarities  do  not  occur  in  the  numerous  specimens  which 
have  come  under  my  observation. 

Tacumshane,  Co.  Wexford.  Bitch  at  railway  station,  Dundalk, 
Co.  Louth.  Stream,  Crossdoney,  Co.  Cavan.  Luean.  Dundmm. 
Boat  harbour.  Dolphin's  bam,  Co.  Dublin.  Boyal  Canal,  Enfield,  Co. 
Heath.  Boyal  Canal,  Kilcock,  Co.  Kildare.  Kilcool,  Co.  Wicklow. 
The  Callows,  Ballinasloe,  Co.  Galway.  Limestone  quarry,  Mullingar, 
Co.  Westmeath.    Lough  Moume  deposit. 


306  Proceedings  of  the  Royal  Irish  Academy. 

Var,  longieepi,  (Ehr.)    Presh  water. 

Like  the  preceding,  but  longer,  more  dender,  the  endB  not  so 
laxge ;  not  triangular,  but  rounded  off.     (PI.  28,  fig.  23.^ 

Synedra  longiceps,  Eab.  SiiBsw.  Diat.,  p.  55.  Balis,  in  Pritch., 
p.  788.  Grunow,  Yerhand.  der  K.  K.  Zool.  Bot.  Geeel.  Band  xii., 
1862,  p.  386. — Synedra  notarisii,  Caatracane,  Dialogo  di  Diat.  raccolte 
nell  Yal.  Intrasea,  p.  9. 

Twyford  Lough,  near  Athlone,  Co.  Westmeath,  unmixed  with  the 
former,  and  mixed  with  it  in  ditch  near  railway  station,  Dundalk,  Go. 
Louth. 

Synedra  ulna,  (Ehr.)    Fresh  water. 

IVustules  on  front  view  linear ;  on  side  yiew  linear,  suddenly  con- 
tracted at  the  ends,  which  are  slightly  constricted  and  rounded ;  strise 
interrupted  in  the  centre  by  a  quadrangular  yacant  space.  (PI.  28, 
fig.  24.) 

It  is  not  easy  to  comprehend  how  Smith  could  have  regarded  as 
one  species  the  two  forms  described  by  him  under  this  name,  B.  D., 
Vol.  i.,  p.  71,  PI.  xi.,  figs.  90  and  90  J^,  than  which  no  two  forms  of 
the  genus  seem  to  be  more  distinct.  The  result  is,  that  great  confu- 
sion has  been  introduced,  which  may  be  dispelled  by  a  careful  com- 
parison of  Eiitzing's  description  and  figure  of  the  species  with  the 
actual  forms.  It  is  questionable  whether  the  form  figured  by  Smith, 
as  above,  fig.  90  B,  really  belongs  to  Synedra  ulna ;  but,  unqestion- 
ably,  that  of  fig.  90  must  be  excluded  from  its  limits. 

Kiitz.  Bac.,  p,  66,  T.  xxx.,  fig.  28.  Eab.  Siissw.  Diat,  p.  54, 
T.  iv.,  fig.  4.  Ealfs,  in  Pritch.,  p.  788,  PL  x.,  fig.  184,  in  which  only 
the  front  view  is  given,  and  the  mode  of  growth  is  on  a  short  stipes, 
and  scattered.  Grunow,  Yerhand.  der  E.  E.  Zool.  Bot.,  Gesel.  Band 
xii.,  1862,  p.  397,  where  he  identifies  this  species  with  Smith's  fig.  90B, 
as  above  cited,  and  makes  fig.  90  a  variety  marked  by  the  name  of 
lanceolata.  Heiberg  refers  to  the  species  as  identical  with  that  of 
Smith's  fig.  90;  De  Danske  Diat.,  p.  64.  Babenhorst  Fl.  Eur.,  sect.  1, 
p.  133,  does  not  refer  to  Smith's  figures,  and  follows  Grunow,  only 
that  he  includes  Synedra  salina,  a  very  distinct  species,  as  a  variety  of 
Synedra  ulna.  Castracane  identifies  the  form  so  named  with  that  of 
Babenhorst  Siissw.  Piat.,  T.  iv.,  fig.  4,  as  well  as  with  that  of  Smith, 
fig.  90.    Catalogo  di  Diat.  raccolte  nell  Yall.  Intrasea,  p.  10. 

Tacumshane,  Co.  Wexford.  Caum  Lough,  near  Tralee,  Glencar, 
Co.  Eerry.  River  Dodder,  Co.  Dublin.  Ditch  near  Wicklow.  Feigh- 
cuUen,  Maynooth,  Co.  Eildare.  Biver  Moy,  Eoxford,  Co.  Mayo. 
Well,  Farraghy,  Co.  Cork. 

Var.  oxyrhynehus,  (Eiitz.)     Fresh  water. 

Much  longer  than  the  typical  species,  and  ends  on  side  view 
sharper.     (PL  28,  fig.  25.) 

Eiitz.  Bac,  p.  66,   T.  xiv.,  fig.  11.     Ralfs,   in   Pritch.,   p.  788. 


O'Meaba — Report  on  the  Iriih  DiatomacecB.  307 

dnmow  makes  Synedra  oxyrhynchus  a  distmct  spedes,  which  he  iden- 
tifies with  Synedra  oxyrhynchns,  Wm.  Sm.,  B.  D.,  Yol.  i.,  p.  71, 
PI.  xi.,  fig.  91,  and  figures  a  yariety  distinguiBhed  as  amphicephala, 
tirhich  appears  identical  with  Synedra  ulna,  Wm.  Sm.,  B.  D.,  Vol.  i., 
p.  71,  PI.  xi.,  fig.  90^.  The  form  under  consideration  seems  diffe- 
rent from  hotii.     Eah.  Fl.  Eur.,  sect.  1,  p.  135,  who  follows  Grunow. 

Biver  Dodder,  near  Dublin.    Biver  Hoy,  Foxford,  Co.  Mayo. 

Var,  amphirhynehus.     £hr.     Fresh  water. 

like  the  typical  species,  from  which  it  differs  chiefly  by  the  ab- 
sence of  the  quadrangular  unstriate  space  in  the  centre  of  the  valve, 
on  side  view.    \^\.  28,  fig.  26.) 

Eiitz.  Bac.,  p.  66,  T.  xiv.,  fig.  15.  Bab.  SUssw.  Diat.,  p.  55, 
T.  iv.,  fig.  7.  Balfs,  inPritch.,  p.  788.  Grunow,  Yerhand.  der  K.K. 
2ool.  Bot.,  Gesel.,  Band  xii.,  1862,  p.  397. 

Biver  Moy,  Foxford,  Co.  Mayo.  Bohemabreena,  River  Dodder, 
pond.  Botanic  Gardens  of  Trinity  College,  Co.  Dublin.  Greenane, 
Kilcool,  Powerscourt,  Co.  Wicklow.  Feighcullen,  Co.  Kildaxe.  Kille- 
shin.  Queen's  County.  "Well,  Farraghy,  Co.  Cork.  Stream  near  Giants' 
Causeway,  Co.  Antrim. 

Mr.  Kitton  of  Norwich,  and  Rev.  George  Davidson,  have  supplied 
me  with  specimens  which  would  appear  to  belong  to  this  variety,  but 
growing  in  short  filaments,  after  the  manner  characteristic  of  Fragi- 
laria.  I  find  no  description  of  the  stipes  in  any  of  the  authors  who 
bave  referred  to  this  form,  nor  have  I  ever  seen  it  myself  in  situ;  but 
not  unfrequently  have  I  noticed  it  aggregated  in  tablets,  but  not 
parallel  at  the  ends,  as  if  the  aggregation  were  accidental. 

Synedra  lonyissima,  (Wm.  Sm.)     Fresh  water. 

Frustules  very  long  on  front  view,  quadrangular ;  on  side  view  li- 
near, till  near  the  ends,  towards  which  it  is  almost  imperceptibly 
attenuated ;  ends  constricted  and  then  dilated,  without  any  central 
free  space ;  valves  sometimes  sHghtly  arcuate.     (PI.  28,  fig.  27.) 

Smith's  description  of  this  species  is  tolerably  accurate ;  but  the 
figure,  B.D.,  Yol.  i.,  PI.  xii.,  fig.  95,  is  calculated  to  mislead.  The 
form  possesses  no  median  line,  nor  is  there  a  central  free  space,  such 
3s  this  figure  represents. 

Wm.  Sm.,  B.  D.,  Yol.  i.,  p.  72.  Ralfs,  in  Pritch.,  p.  786,  who 
asks  "is  this  distinct  from  Synedra  biceps?"  to  which  I  reply,  cer- 
tainly it  is.  The  forms  differ  greatly  in  their  general  appearance, 
and  may  be  discriminated  by  the  fact  that  the  strisB  in  Synedra  bi- 
ceps are  pervious — in  Synedra  longissima  they  are  separated  by  a 
median  sulcus.  Cleve,  Cm  Svenska  och  Norska  Diat.,  220.  Rab. 
Fl.  Eur.,  sect  1,  p.  130,  who  remarks  that  **it  appears  to  him  an 
elongated,  gently-undulate  form  of  Synedra  biceps,"  .and  strangely 


308  Proceedings  of  the  Royal  Irish  Academy, 

adds,  that  '*  he  considers  Gnmow  has  rightly  regarded  it  as  a  variety 
of  Synedra  splcndens." — Synedra  splendens,  var.  longissima,  Gnmow^ 
Yerhand.  der.  £.  K. Zool. Bot.  Gesel.,  Band  xii.,  1 862,  p.  397.  Grunow 
considers  this  form  identical  with  Synedra  biceps,  Ktitz.  Bac,  p.  66^ 
T.  xiv.,  figs.  18  and  21,  and  Rab.  Sxissw.  Diat.,  p.  55,  T.  v.,  fig.  9. 
But  however  this  may  be,  Synedra  longissima  and  Synedra  biceps  are 
in  reality  distinct  species. 

Pond  in  Botanic  Gardens,  Belfast.  Malahide.  St  Fenton's  Well^ 
Button.  Streamlet,  Newcastle  Lyons,  Co.  Dublin.  Twyford  Lake^ 
near  Athlone,  Lake  Belvidere,  Co.  Westmeath.  Ditch  near  railway 
station,  Dnndalk,  Co.  Louth.     Ditch  near  Wicklow. 

Synedra  ohtusa,  (Wm.  Sm.)     Fresh  water. 

Similar  to  the  preceding  species,  but  much  shorter ;  not  so  much 
constricted  or  expanded  at  the  rounded  ends.     (PL  28,  fig.  28.) 

Wm.  8m.,  B.  D.,  Vol.  i.,  p.  71,  PL  xi.,  fig.  92,  who  regards  it  as 
»  Synedra  ulna,  Ehr.  Inf.,  T.  xvii.,  fig.  1 ;  but  of  this  he  is  doubtful; 
and  Synedra  scqualis,  Kiitz.  Sp.  Alg.,  p.  45,  ad  speciem  quae  dedit 
amico  De  Brebisson.  If  Synedra  sequalis,  Kiitz.,  just  referred  to,  bo 
the  same  as  that  described  by  the  same  author,  Bac,  p.  66,  T.  xiv.» 
fig.  14,  it  is  scarcely  identical  with  the  present  species. — Synedni 
splendens,  var.  obtusa,  Grunow,  Yerhand.  der  K.  K.  Zool.  Bot. 
GeseL,  Band  xii.,  1862,  p.  397. — Synedra  splendens,  var.  sequalis,. 
Rab.  Fl.  Eur.,  sect.  1,  p.  134.  The  linear  form  of  the  side  view 
appears  to  me  to  distinguish  this  from  the  form  named  Synedra  splen- 
dens by  both  the  authors  last  referred  to,  which  Grunow  describes  as 
generally,  small  lanceolate,  and  less  frequently  linear,  and  Eabenhorst 
as  linear,  lanceolate.  If  this  form  can  be  regarded  as  a  variety  of  any 
other,  I  think  it  should  be  of  Synedra  longissima,  which  it  very  closely 
resembles. 

Tacumshane,  Co.  "Wexford  ;  Ditch  near  railway  station,  London* 
deny.*  Limestone  quarry,  Mullingar.  Twyford  Lake,  near  Athlone. 
Lake  Belvidere,  Co.  Westmeath. 

(e).  Stria  interrupted  hy  a  narrow,  longitudinal  iulew ;  valves,  narrour 
elliptical, 

Synedra  splendens,  (Kiitz.)     Fresh  water. 

Frustules  long :  on  front  view  usually  wider  at  the  ends  than  in 
the  middle  ;  on  side  view,  narrow  elliptical,  gradually  attenuated  to> 
the  slightly  capitate  ends.     (PL  28,  fig.  29). 

I  have  found  it  impossible  to  discriminate  between  this  specie» 
and  Synedra  ulna,  as  described  by  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  71^ 
PL  xi.,  fig.  90.  The  latter  species,  as  described  by  Eiitzing  Bac.,. 
p.  66,  T.  xxxx.,  fig.  28.,  is  on  side  view  perfectly  linear;  and 
although  I  have  occasionally  seen  specimens  which  exhibit  a  ten- 


O'Meara — Report  an  the  Irish  DiatomacecB,  309 

dencj  towards  the  elliptical  outline,  I  am  disposed  to  regard  these  as 
abnormal,  the  normal  character  being  liaear.  Smith  indeed  distin- 
guishes the  two  forms  by  the  fact  that,  in  the  latter,  the  frustules 
are  loose  and  scattered,  whereas  in  the  former  they  are  arranged 
radiately ;  and,  although  such  a  feature  of  growth  is  not  to  be  wholly 
overlooked,  it  is  scarcely  sufficient  to  distinguish  the  species,  especially 
in  the  earlier  stages  of  growth,  where  the  frustules  are  few  in  number. 
I  am  inclined  to  think  the  form  which  Smith  describes  as  Synedra 
ulna  is  really  Synedra  splendens.  It  seems  strange  that  this  form 
should  have  been  attributed  to  Wm.  Smith,  although  he  regards  what 
he  calls  Synedra  radians  as  equivalent  to  Synedra  splendens,  Kiitz. 

Kiitz.,  Bac.,  p.  66,  T.  xiv.,  fig.  16;  Rab.  Sussw.  Diat.,  p.  54, 
T.  iv.,  fig.  4  ?  Ealfs,  in  Pritch.,  p.  788.  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesel.,  Bandxii.,  p.  394. — Synedra  radians,  Wm.Sm.,  B.D., 
Vol.  i.,  p.  71,  PL  xi.,  fig.  89.  Heiberg,  De  Danske  Diat.,  p.  64. 
Castracane,  Catalogo  di  Diat.  raccolte  nell  Yal  Intrasca,  p.  10.  Cleve^ 
Om  Svenska  och  Norska  Diat.,  p.  220. 

Stream,  Crosedoney.  Derrylane  Lough,  Co.  Cavan.  Lucan.. 
Friarstown,  Bohemabreena,  Malahide,  Co.  Dublin.  Tacumshane,  Co. 
Wexford.  Eilleshin,  Queen's  Co.  Eoyal  Canal,  Enfield,  Co.  Meath. 
Glencar.  Pedlar's  Lough,  near  Dingle,  Co.  Kerry.  Ditch  near  railway 
station,  Dundalk,  Co.  Louth.   Eiver  Suck,  Ballinasloe,  Co.  Galway. 

Var.  radtanSy  (Kiitz.)  Presh  water. 

Like  the  typical  species,  but  smaller,  and  the  ends  more  acute  on 
side  view.     (PI.  28,  fig.  30.) 

Kiitz.  Bac.,  p.  64,  T.  xiv.,  fig.  7.  EaHs,  in  Pritch.,  p.  787.— Syne- 
dra  radians,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  71,  PI.  xii.,  fig.  89  B, 
and  89  y. 

Friarstown,  Co.  Dublin.  Derrylane  Lough,  Co.  Cavan.  Pedlar'a 
Lough,  near  Dingle,  Co.  Kerry.  Ditch  near  Dundalk,  Co.  Louth. 
Ditches  in  the  Callows,  Ballinasloe,  Co.  Galway. 

Var.  daniea,  (Kiitz.)    Fresh  water. 

Frustules  longer  and  narrower  than  the  typical  species,  the  stria- 
tion  finer,  and  the  valves  on  front  view  more  gradually  attenuated 
towards  the  ends,  which  are  broadly  rounded  ojff,  and  not  capitate. 
(PL  28,  fig.  31.) 

Kutz.  Bac,  p.  66,  T.  xiv.,  fig.  13.— Ralfs,  in  Pritch.,  p.  788; 
Synedra  radians  var.  debilis,  Rab.  Fl.  Eur.,  sect.  1,  p.  134  ?  Grunow 
considers  this  var.  =  Synedra  radians,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  71, 
PL  xii.,  figs.  89  B,  and  89  y ;  Verhand.  der  K.  K.  Zool.  Bot.,  GeseL, 
Band  xii.,  p.  396 ;  but  Synedra  daniea  is  much  longer  than  that 
variety,  less  lanceolate,  and  with  broader  rounded  apices. 

"River  Moy,  near  Foxford,  C.  Mayo.  Bantry  Well,  Farraghy,  Co. 
Cork.  Donoughmore,  Co.  Tyrone.  Coolnamuck,  parish  of  Dysert,  Co.. 
Waterford. 


310  Proceedings  of  the  Eoyal  Irish  Academy. 

Synedra  salina,  (Wm.  Sm.)    Marine. 

Yalve  lanceolate,  gradually  attenuated  towards  the  endfl,  which  are 
rounded  off,  and  broader  than  in  Synedra  splendens.     (PL  28,  fig.  32.) 

Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  71,  PL  xi.,  fig.  88.  Ralfe,  in  Pritch., 
p.  787.  Grunow,  Yerhand.  der  K.  £.  ZooL  Bot.  Gesel.  Band  xii. 
p.  398. — Synedra  ulna,  var.  marina  Bab.  PI  •  £ur.,  sect.  1,  p.  134. 

Tacumshane,  Co.  "Wexford.  Malahide,  Clontarf,  Co.  Dublin.  Eos- 
trevor,  Co.  Down.   Stomachs  of  Ascidians,  Boundstonc  Bay,  Co.  Oalway. 

Synedra  yaliionti,  (Ehr.)     Marine. 

Frustules  on  front  view  slightly  attenuated  at  the  ends,  on  side 
view  shorter,  broader,  and  more  obtuse  at  ends  than  in  case  of  Synedra 
salina.     (PL  28,  fig.  33.) 

Kiitz.  Bac,  p.  68,  T.  xxx.,  fig.  42.  Wm.  Sm.,  B.D.,  Vol.  i.,  p. 
74.  Supp.  PL  XXX.,  fig.  265,  who  describes  a  shorter  and  stouter 
var.  ib,,  Supp.  PL  xxx.,  fig.  265  B.  Ralfs,  in  Pritch,  p.  788,  PL 
xii.,  figs.  34.36.  Grunow,  Verhand  der  K.  K.,  ZooL  Bot.  Gesel., 
Band  xii.,  1862,  p.  401.  Eab.  Fl.  Eur.,  sect.  1,  p.  137,  who  attributes 
the  species  to  Bory. 

On  seaweeds,  Bannow,  and  Tacumshane,  Co.  Wexford.  On  sea- 
weeds, Malahide,  Co.  Dublin.  Seaweeds,  Lame,  Co.  Antrim.  Sea- 
weeds, Dundrum  Bay,  Co.  Down.  Arran  Islands,  Co.  Galway,  and 
from  seaweeds  at  different  parts  of  the  coast  in  the  Co.  Clare. 

The  smaller  variety  has  been  found  at  Malahide,  Howth,  Co. 
Dublin.  On  seaweeds.  Lame,  Co.  Antrim,  and  in  the  other  localities 
where  the  larger  species  has  occurred. 

Synedra  ipathulata,  N.  S.     Fresh  water. 

Frustules  very  large;  length,  -0130 ;  on  front  view  wider  at  ends 
than  middle;  greatest  breadth,  '0012;  ends  straight;  on  side  view 
wider  in  the  middle,  and  gradually  attenuated  towards  the  ends,  at 
some  distance  from  which  '0028,  bending  inwards  and  then  outwards, 
then  suddenly  constricted  towards  the  broadly  capitate  rounded  extre- 
mities.    Strioe  course,  costate.     (PL  28,  fig.  34.) 

Ditch  at  bank  of  Royal  Canal,  near  Kilcock,  Co.  Blildare.  An  un- 
dulate variety  of  the  species  occurs  in  a  well,  Newcastle,  Lyons,  Co. 
Dublin. 

Synedra  harhatulaf  (Kiitz.)    Marine. 

Frustules  short,  on  front  view  quadrangular ;  on  side  view  broadly 
elliptical ;  strise  fine,  but  distinct.     (PL  28,  fig.  35.) 

Kiitz.  Bac.,  p.  68,  T.  xv.,  fig.  104.  Ralfs,  in  Pritch.,  p.  789. — 
Synedra  gracilis,  var.  barbatula,  Grunow,  Verhand.  der  K.K.Zool.  Bot., 
OeseL,  Band  xii.,  p.  402. 

Salthill,  Co.  Dublin.  Stomachs  of  Ascidians,  Roundstone  Bay, 
do.  Galway.     Seaweeds,  Tramore,  Co.  Waterford. 


O'Meaba — Report  on  the  Irish  Diatomacew,  311 

(f . )  Stria  marginal. 

Synedra  tahulata,  (Agardli.)    Marine. 

Pmstules  large,  adhering  in  tablets  on  a  short  stipes;  on  front  view 
wider  at  middle  than  at  the  ends ;  on  side  view  nearly  linear,  very 
slightly  attenuated  towards  the  constricted  and  ronndcd  ends ;  stri» 
broader  than  in  the  succeeding  species.     (PI.  28,  fig.  36.) 

Kiitz.  Bac.,  p.  68,  T.  xv.,  figs.  101-3,  where  the  form  is  described 
more  in  accordance  with  my  specimens  than  that  of  Wm.  Sm.,  £.  D., 
Vol.  i.,  p.  72,  PI.  xii.,  fig.  96.  Ralfs,  in  Pritch.,  p.  788 ;  Grunow, 
Verhand.  der  K.  K.  Zool.  Bot.,  Gesel.,  Band  xii.,  1862,  p.  403.  Kab. 
H.  Eur.  Alg.,  sect.  1,  p.  137.  Cleve,  Om  Svenska  och  Norska  Diat., 
220.  According  to  Kiitzing  =  Diatoma  tabulatum,  Agardh,  on 
which  authority  I  attribute  the  species  to  Agardh,  as  do  also  Balfs 
and  Eabenhorst,  while  Smith,  Cleve,  and  Grunow,  the  latter  doubt- 
fully, refer  it  to  Eiitzing. 

On  seaweeds,  Bannow,  Co.  Wexford,  as  well  as  on  seaweeds  near 
the  town  of  Wexford.  Seaweeds,  Rostrevor,  Co.  Down.  Seaweeds, 
Malahide,  Co.  Dublin.  Laytown,  Co.  Meath.  Breaches  near  New- 
castle, Co.  Dublin.     Seaweeds,  Larne,  Co.  Antrim. 

Sf/nedra  areut,  (Kiitz.)    Marine. 

Frustules  much  smaller  than  those  of  the  preceding  species,  and 
not  dissimilar  in  their  mode  of  growth ;  on  front  view  slightly  arcu- 
ate; on  side  view  slightly  sigmoid;  striae  short.     (PI.  28,  fig.  37.) 

Kiitz.  Bac,  p.  68,  T.  xxx.,  fig.  50.  Wm.  8m.,  B.  D.,  Vol.  i.,  p. 
70,  PI.  xi.,  fig.  98,  PI.  xii.,  fig.  98,  in  which  latter  the  front  view  and 
manner  of  growth  are  accurately  depicted.  Ealfs,  in  Pritch.,  p.  789, 
PI.  iv.,  fig.  27,  where  the  front  view  is  represented  as  straight  and 
perfectly  quadrangular,  and  the  side  view  as  arcuate,  and  with  a 
median  line^  the  striae  reaching  the  latter ;  in  all  these  particulars  the 
figure  is  not  correct.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel., 
Band  xii.,  p.  405.  Heiberg,  De  Danske  Diat.,  p.  65.  Rab.  Fl.  Eur., 
sect.  1,  p.  138. 

On  seaweeds,  Malahide,  Monkstown,  Bray,  Co.  Dublin. 

Synedra  afflntSf  (Kiitz.)    Marine. 

Pmstules  in  mode  of  growth  similar  to  the  preceding ;  on  front 
view  attenuated  at  ends ;  on  side  view  lanceolate ;  striae  fdiort.  (PL 
28,  fig.  38.) 

Kiitz.  Bac,  p.  68,  T.  xv.,  fig.  6.  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  73, 
PI.  xii.,  fig.  97.  Kalfs,  in  Pritch.,  p.  788.  Grunow,  Verhand.  der 
K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  403.  Kab.  El.  Eur.^ 
sect.  1,  p.  138. 

Tide-pool,  Wexford.  Tacumshane,  Co.  Wexford.  On  sea-weeds^ 
Malahide  and  Clontarf,  Co.  Dublin.      Camlough  Bay,  Co.  Antrim. 


312  Proceedings  of  the  Royal  Irish  Academy. 

Bostrevor  and  Dundmm  Bay,  Co.  Down.     Breaches  near  Newcastle, 
Co.  Wicklow.    Mouth  of  the  Nannywater,  Laytown,  Co.  Meath. 

Synedra  nituchiodei,  (Gran.)    Marine. 

Prustules  on  front  view  slightly  attenuated  towards  the  ends ;  on 
side  yiew  narrow,  linear  lanceolate.     (Fl.  28,  fig.  39.) 

Grunow  do«s  not  describe  the  mode  of  gronrth,  nor  can  I  say  any- 
thing on  this  subject,  as  the  form  has  been  observed  by  me  only  after 
treatment  with  acid.  This  species  may  be  distinguished  from  tibe  last 
by  the  linear  and  slightly  apiculate  form  of  the  side  view. 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  p.  403, 
T.  v.,  fig.  18.  This  species  was  found  by  Grunow  only  in  the  Pacific 
Ocean. 

Erom  stomachs  of  Ascidians,  Eoundstone  Bay,  Co.  Galway.  From 
seaweeds,  Bush,  Co.  Dublin,  where  it  occurs  in  tolerable  abundance. 

Synedra  frauen/eldiif  (Grun.)     Marine. 

Frustules  much  larger  than  the  three  preceding  species  on  front 
view,  but  very  slightly  attenuated  at  the  ends ;  on  front  view  narrow, 
lanceolate,  much  attenuated  from  the  middle  towards  the  ends,  which 
are  slightly  dilated ;  striee  fine,  marginal  in  the  middle,  but  as  the 
valves  become  narrow  towards  the  ends,  they  seem  to  meet.  (PL  28, 
fig.  40.) 

Grunow,  Verhand.  dcr  K.  K.  ZooL  Bot.  Gesel.,  Band  xii.,  1862,  p. 
406,  T.  iv.,  fig.  26.     The  only  habitat  given  by  Grunow  is  the  Bed  Sea, 

Seaweeds,  Dundalk,  Co.  Louth.  The  form  is  more  slender  than 
that  figured  by  Grunow  as  above,  the  apex  less  dilated,  and  the  strias 
shorter ;  but  in  the  main  features  the  forms  are  so  like  as  to  leave 
but  little  doubt  of  their  identity. 

Synedra  puisaliSf  N.  S.     Presh  water. 

Frustules  in  length  -0045,  very  narrow ;  on  front  view  slightly 
attenuated  towards  the  ends ;  on  side  view  narrow,  lanceolate,  gra- 
dually tapering  towards  the  rostrate  ends ;  striro  short ;  stipes  short ; 
on  which  the  frustules  are  crowded  in  small  tablets  containing  about 
ten  in  each.     (PI.  28,  fig.  41.) 

This  form  possibly  may  be  identical  with  that  dcBcribed  as  Synedra 
tenuis,  by  Kiitzing,  Bac,  p.  65,  T.  xiv.,  fig.  10,  but  in  some  respects 
it  is  so  different  as  to  warrant  the  conclusion  that  it  is  specifically 
distinct.  Kiitzing  does  not  describe  the  mode  of  growth  nor  the 
character  of  the  strisB,  and  moreover  alleges  that  in  the  species  re- 
ferred to,  the  frustules  are  exactly  linear  on  front  view,  whereas  in 
the  present  case  they  are  obviously  attenuated. 

St.  Fenton's  Well,  Sutton,  Co.  Dublin.  Well  near  the  Roman 
Catholic  Chapel,  Ballinasloe,  in  both  which  localities  it  occurs  in 
great  abundance,  mixed  with  other  forms. 


O'Meara — Report  an  the  Irish  Dtatomaceie.  313 

Synedra  Smithii,  N.  S.     Fresh  water. 

Frastules  small ;  on  front  view  quadrangular ;  on  side  view  nar- 
row, linear;  accuminate  at  the  ends;  strisB  short.  (PL  28,  fig. 
42.) 

Synedra  vaucheriae,  "Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  73,  PL  xi., 
fig.  99,  who  identifies  the  species  with  that  so  named  hyEiitzing,  Bac, 
p.  65,  T.  iv.,  fig.  4,  1,  2a,  3 ;  and  so  far  as  the  description  of  it  is 
concerned,  not  without  warrant :  but  although  in  some  respects  the 
£gare8  cited  seem  to  agree  with  the  form  under  notice,  in  other  re- 
spects there  is  such  a  difference  as  to  cast  a  doubt  on  the  correctness 
of  the  identification.  Kiitzing  represents  the  striation  in  his  form  as 
pervious,  whereas  in  that  figured  and  described  by  Smith  the  stri® 
are  marginal  and  very  short.  Babenhorst  describes  and  figures  a  form 
under  the  name  of  S.  vaucheriae ;  but  although  from  the  description  it 
might  fairly  be  supposed  to  be  the  same  as  the  present  form,  the  figure 
renders  the  identity  more  than  doubtful ;  Siissw.  Diat.,  p.  55,  T.  iv., 
fig.  15.  Again,  Grunow  describes  a  form  as  identical  with  Kiitzing' s 
Synedra  vaucheriae ;  Yerhand.  der  K.  K.  Zool.  Bot.  G^sel.,  Band  xii., 
1862,  p.  393,  T.  v.,  fig.  9,  which  seems  to  differ  widely  from  Kutzing*s 
figure,  as  well  from  that  so  named  by  Wm.  Smith.  He  remarks : — 
"  The  species  here  referred  to,  which  exhibits  a  decided  relationship 
to,  Synedra  pulchella,  I  regaided  for  a  long  time  as  the  identicid 
Synedra  vaucheriae  of  Kiitzing  and  recently  had  my  impression  on  the 
fiubject  confirmed  through  means  of  some  specimens  of  J)e  Br^bisson's, 
kindly  sent  to  me  by  Professor  A.  Braun.  I  find  Smith's  figure 
widely  different  from  Synedra  vaucheriae,  Kiitz.,  which  might  much 
rather  be  regarded  as  a  form  of  Synedra  affinis,  although  Synedra 
vaucheriae  also  possesses  a  tolerably  broad  unstriate  space  between 
the  striae,  but  in  the  description  I  find  no  allusion  to  the  unstriato 
very  fine  ring-formed-pseudo-nodule."  These  remarks  make  it  obvious 
that  it  is  impossible  to  identify  Smith's  form  with  Synedra  vaucheriae, 
Kiitz.,  from  which  it  differs  considerably.  I  have  therefore  adopted 
a  new  specific  name,  that  of  Synedra  Smithii. 

Tacumshane,  Co.  Wexford.  Biver  at  Port-na-Crush,  Co.  Donegal, 
Malahide,  Portmamock,  St.  Fenton's  WeU,  Sutton,  Co.  Dublin. 

(g.)     StrtiB  obsolete, 

Synedra  dehiliSf  (Kiitz.)    Presh  water. 

Frustules  very  minute ;  on  front  view  regularly  quadrangular ;  on 
«ide  view  elliptical-lanceolate.     (Plate  28,  fig.  43.) 

Kiitz.  Bac,  p.  65,  T.  iii.,  fig.  45.  Ralfs,  in  Pritch.,  p.  787.— 
Synedra  radians,  var.  debilis,  Rab.  Fl.  Eur.,  sect.  1,  p.  136. 

Twyford  Lake,  near  Athlone,  Co.  Westmeath.  River  Dour, 
€o.  Cork. 


314  Proceedings  of  the  Royal  Irish  Acadetny. 

FAMILY  VI.     STRIATELLEiE,   Kiitz. 

PmstuleB  precisely  as  in  the  immediately  preceding  family,  and* 
distinguished  by  the  possession  of  internal  diaphragms,  which,  spring- 
ing from  the  connecting  membrane,  are  interposed  between  the  twa 
opposite  valTes. 

This  family,  since  it  was  constituted  by  Kiitzing,  has  been  adopted 
by  succcssiye  authors,  but  with  some  divergence  rcspectiag  the  species 
comprehended  within  its  limits.  As  here  defined,  it  embraces  not 
only  the  genera  included  in  Eiitzing's  family  Striatelle®,  but  also 
those  of  the  family  Tabellaricae,  which,  though  generically  distinct, 
come  properly  within  the  same  limits.  The  Genera  Gephyria  and 
Eupluria,  which  were  included  by  Ralfs,  are  here  excluded  from  the 
family ;  because  in  whatever  other  respects  they  may  agree,  they  stand 
remote  in  consequence  of  the  unsymmetrical  structure  of  the  opposite 
valves.  And  for  a  similar  reason  I  exclude  Podosphenia,  which  Hei- 
berg  placed  in  the  family,  the  frustules  being  unsymmetrical  both  on 
front  and  side  view. 

Thus  defined,  the  family  is  precisely  equivalent  to  Grunow's  sub- 
group of  Diatomeoe,  and  stands  out  disting^shed  by  two  very  decided 
features,  namely,  the  perfect  symmetry  of  the  valves,  and  Uie  inter- 
position between  them  of  diaphragms  more  or  less  numerous. 

The  diaphragms  constitute  so  important  a  feature  in  the  family, 
that  some  observations  are  needed  to  explain  their  nature  and  mode  of 
growth.  As  far  as  I  know,  Ealfs  was  the  first  who  described  these 
organs  with  any  tolerable  approach  to  accuracy.  He  says: — "The 
appearance  of  longitudinal  stns  is  in  fact  produced  by  silicious  plates, 
arising  internally  from  the  margins  of  the  filament,  and  extend- 
ing towards,  but  not  reaching,  the  centre.  The  interior  is  thus 
divided  into  chambers  opening  into  a  central  space.  When  viewed 
laterally,  this  central  space  resembles  a  canal,  especially  as  the  inner 
edge  of  each  plate  has  a  concave  outline."  Balfs,  in  Fritch.,  p.  803. 
If  there  be  anything  vague  in  this  description,  it  is  greatly  elucidated 
by  the  observations  of  Wm.  Smith,  as  well  as  by  the  figures  of  these 
diaphragms  in  the  case  of  Khabdonema,  Tetracyclus,  and  Tabellaria, 
B.  D.,  Yol.  ii.,  pp.  32-34,  PL  xxxviii.,  fig.  306  h  and  306t,  ^^'  xxxix., 
fig.  308  h  and  h',  PL  xliii.,  fig.  316t  and  3l7t. 

In  these  cases,  the  diaphragms  may  be  regarded  as  compressed 
rings  corresponding  externally  with  the  outline  of  the  valves;  but 
Heiberg  has  called  attention  to  the  fact  that,  in  the  case  of  Striatella, 
the  diaphragms  are  somewhat  difFerently'constructed.  "  Smith's  repre- 
sentation of  the  structure  of  this  species  is  in  the  main  correct,  but  he 
has  misapprehended  the  form  of  the  diaphragms,  considering  them  to 
be  closed  rings  (as  his  figure  307  h,  as  well  as  the  descriptive  term, 
'' Annuli"  indicate),  whereas  in  reality  they  are  open  at  one  end.  The 
form  of  them  would  naturally  be  best  seen  by  preparing  them  out  sepa- 


O'Meara — Report  on  t/te  IrUh  Diatoniaceae,  31& 

rately.  One  ean,  hawever,  satisfy  himsell  that  the  diaphragms  ara 
open  at  one  end,  by  observing  a  perfect  fmstnle  in  transverse  viewv 
when  <me  diaphragm  is  seen  from  the  open,  and  the  other  from  the 
dosed,  side.**— DeDanske  Diat.,  p.  72.  In  the  case  of  the  diaphragmB 
of  Striatella,  it  may  be  noticed  that  the  silicious  plate  is  tlucker  at 
one  end,  and  beoomes  gradually  thinner  as  it  recedes  from  it.  This 
fact  may  serve  to  illustrate  the  mode  of  growth  in  the  diaphragms  in 
other  species,  as  weU  as  in  Striatella.  Springing  from  opposite  ends^ 
the  two  contiguous  diaphragms  in  some  cases  appear  much  thicker  at 
the  starting  point,  and  as  they  proceed  parallel  to  each  other  become 
thinner  and  thinner  as  they  approach  the  opposite  end  of  the  frustule. 
The  strong  limes  which  appear  as  costse  on  the  front  view  may  seem  to 
nuurk  the  extreme  length  to  which  the  diaphragms  project  into  the  c^ ; 
but  the  compressed  rings  are,  except  in  the  case  of  Striatella,  com- 
plete, and  can.  by  proper  focusing  be  traced  through  their  entire 
oourse.  # 

Genus  I.     Gsahmatophoka,  (Ehr.) 

Frustules  attached,  united  in  zig-zag  filaments  ;  diaphragms  two  in 
number ;  open  in  the  centre,  and  equally  developed  at  both  sides  of 
the  same.  Yalves  narrow,  elliptical  \  sometimes  slightly  expanded  in 
the  middle ;  strisB  obvious,  and  appearing  on  front  view  as  a  narrow 
striate  border. 


Although  the  species  of  this  genus  ore  by  the  experienced  eye 
easily  discriminated,  it  is  not  easy  to  describe  their  characteristics 
in  words  so  as  satisfactorily  to  obviate  confusion  with  other  forms 
belonging  to  the  same  family,  e^ecially  with  Tabellaria,  which  they 
resemble,  not  only  in  the  mode  of  growth  in  zig-zag  filaments,  but 
also  in  the  general  formation  of  the  diaphragms,  which  are  equally 
developed  on  both  sides  of  the  central  portion.  Whether  we  view  the 
frustules  on  the  front  or  side  views,  they  may  be  distinguished  by  the 
following  characters : — In  Grammatophora  the  valves  are  sometimes 
slightly  expanded  in  the  middle,  but  in  no  case  so  much  so  as  in  Tabel- 
laria ;  the  strise,  too,  are  ever  noticeable,  which  is  not  the  case  with 
the  last-named  genus.  And  on  the  front  view  the  narrow  margin  of 
striaB  noticeable  in  the  species  of  Grammatophora  are  never  to  be  seen 
in  those  of  Tabellaria. 

Grammatophora  murina^  (Lyngb.)     Marine. 

Frustules  on  front  view  regularly  quadrangular;  on  side  view 
narrow,  elliptical ;  stri®  obvious ;  diaphragms  curved  near  the  ends, 
and  thence  running  in  a  straight  line  towards  the  middle.     (PL  29, 

%.  1.) 

Kiitz,  Bac.,  p.  128,  T.  xvii.,  fig.  24,  who  regards  the  speeies  as 
identical  with  Diatoma  marina,  Lyngb.     Wm.  Sm.,  B.  D.,  Tol.  ii., 

m.x.A.  ntoc.,  BIB.  n.,  vol.  n.,  soaxrci.  2  P 


316  Proceedings  of  the  Eoyal  Irish  Academy. 

p.  42,  PI.  xlii.,fig.  314.  Ralfs,  in  Pritcli.,  p.  808,  PI.  iv.,  fig.  47, 
PL  xi.,  fig.  62  and  53.  Grunow,  Yerhand.  der  E.  K.  Zool.  Bot.  GeseL, 
Band,  zii.,  1862,  p.  415.  Heiberg,  Be  Panske  Diat.,  p.  71.  Eab.  Fl. 
Eur.,  8.  1,  p.  303.     Cleye,  Cm  Svenska  och  Norska  Diat.,  p.  222. 

Sea-weeds,  Malahide.  Sea-weeds,  Portmamock,  Co.  Dublin.  Sea- 
weeds, Portnish ;  and  same,  Co.  Antnm.  Airan  Islands,  Co.  Galway. 
Taonmshane,  Co.  Wexford. 

Gframmatophora  maeilenta^  (Wm.  Sm.)     Marine. 

Pnistules  on  front  view  quadrangular,  but  sometimes  slightly 
arcuate  ;  generally  much  longer  than  the  preceding  species ;  on  side 
view  nearly  linear;  diaphragms  similar  to  the  last,  except  that  the 
foramen  is  more  elliptical,  and  the  striiB  finer. 

Wm.  8m.,  B.  D.,  Vol.  ii.,  p.  43.  Supp.  PL  Ixi.,  fig.  382.  Balfs, 
inPritch.,  p.  808.  Eab.  El,  Eur.,  sect.  l,p.  304.  Cleve,  OmSvenska 
och  Norska  Diat.,  p.  222.— Grammatophora  oceanica,  var.  macilenta, 
Grunow,  Yerhand.  der  E.  E.  Zool.  Bot.  GeseL,  Band  xii.,  1862, 
p.  417. 

Salt  ditch,  near  Wexford.  Tacumshane,  Co.  Wexford.  Camlough 
Bay,  Portnish.  Waterfoot,  Co.  Antrim.  Dundrum  Bay,  Co.  Down. 
Arran  Islands,  Co.  Galway. 

Orammatophora  serpentina^  (Ralfs.)    Marino. 

Frustules  on  front  view  regularly  quadrangular;  on  side  view 
linear  eUiptic ;  striae  obvious ;  diaphragms  undulate,  and  seen  on  front 
view  spiral.     (PL  29,  fig.  2.) 

Eutz.  Bac,  p.  129,  T.  xxix.,  fig.  82.  Wm.  Sm.,  B.  D.,  Yol.  ii., 
p.  43,  PL  xlii.,  fig.  315.  Ralfs,  in  Pritch.,  p.  808,  PL  iv.,  fig.  48. 
Grunow,  Yerhand.  der  E.  E.  Zool.  Bot.  GeseL,  Band  xii.,  1862,  p.  420. 
Rab.  FL  Eur.,  sect.  1,  p.  304.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  222. — Striatella  serpentiaa,  Ralfs.  An.  Nat.  Hist.,  Yol.  ii.,  PL  ix., 
fig.  6. 

Malahide,  Co.  Dublin.  Sea- weeds  near  town  of  Wicklow.  Tacum- 
shane, Co.  Wexford.  Portrush,  Co.  Antrim.  Arran  Islands,  Co. 
Galway. 

Orammatophora  hal/ourianaf  (Wm.  Sm.)     Fresh  water. 

Frustules  small ;  on  front  view  quadrangular ;  on  side  view  linear, 
elliptical ;  diaphragms  direct,  without  curvature ;  striae  fine. 

Ralfs,  following  Greville,  establishes  a  new  genus  Diatomella  to 
receive  this  single  form,  and  is  followed  in  this  view  by  Grunow  and 
Rabenhorst ;  but,  as  it  appears  to  me,  the  characters  are  not  such  as  to 
distinguish  the  new  genus  from  Grammatophora. 

Wm.  Sm.,  B.  D.,  Yol.  ii.,  p.  43,  Supp.  PL  Ixi.,  fig.  383.    Ralfs,  in 


O'Meara — Report  on  the  Irish  Bmtomacece.  317 

Pritch.,  p.  810,  PL  iv.,  fig.  51,  52.  Grunow,  Vcrhaiid.  dcr  K.  K.  ZooL 
Bot.  Gesel.,  Band  xii.,  1862,  p.  319.     Rab.  Fl.  Eur.,  sect.  1,  p.  300. 

Lough  Derg,  Co.  Galway.  Ulster  Canal,  near  Newry,  Co.  Armagh. 
Only  a  few  forms  were  found  in  these  localities,  the  species  being  one 
of  the  rarest  in  Ireland. 


Genus  II.     Tabellakia,  Ehr. 

Frustules  attached  in  zig-zag  filaments ;  valves  expanded  at  the 
middle  and  ends ;  stii®  faint. 


TaheUarta  flocculoaa^  (Roth.)     Fresh  water. 

Diaphragms  numerous,  thickened  ends  alternately  placed,  jmd 
varying  in  length.     (PI.  29,  fig.  3.) 

Kiitz.  Bac,  p.  127,  T.  xvii.,  fig.  21.  Eab.  Siissw.  Diat.,  p.  63, 
T.  X.,  fig.  2.  Wm.  Sm.  B.  D.,  Vol.  ii.,  p.  45,  PI.  xliii.,  fig.  316. 
Ealfs,  in  Pritch.,  p.  807,  PI.  xiii.,  fig.  29.  Grunow,  Yerhand.  der  K 
K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  410.  Heiberg,  De  Danske 
Diat.,  p.  70.  Castracane,  Catalogo  di  Diat.  raccolte  nell  Val  Intrasca, 
p.  15.  Cleve,  Om  Svenska  och  Norska  Diat.,  p.  221. — Tabdlaria 
ventricosa,  Eiitz.  Bac,  p.  127,  T.  xxx.,  fig.  74,  does  not  differ  from 
the  present  species. 

Frequent,  especially  in  sub- Alpine  and  boggy  pools.  Kutzing  re- 
gards this  species  as  identical  with  Conferva  flocculosa.  Roth.,  on  which 
authority  the  species  is  attributed  to  Roth. 

Tabellaria  fenestrata,  (Lyngb.)     Fresh  water. 

Diaphragms  few,  and  of  equal  thickness  on  both  sides  of  the  cen- 
tral expansion ;  frustules  much  longer  than  in  the  preceding  species. 

Kiitz.  Bac.,  p.  127,  T.  xvii.,  fig.  22,  T.  xviii.,  fig.  2,  and  T.  xxx., 
fig.  73,  who  regards  the  species  as  identical  with  Diatoma  f  enestratum 
Lyngbye.  Rab.  Sussw.  Diat.,  p.  68,  T.  x.,  fig.  1.  Wm.  Sm.,  B.  D,, 
Vol.  ii.,  p.  46,  PI.  xlviii.,  fig.  317.  Ralfs,  in  Pritch,  p.  807.  Grunow, 
Verhand.  der  £.£[.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  410.  Heiberg, 
De  Danske  Diat.,  p.  71.  Castracane  Catalogo  di  Diat.  raccolte  nell  Val 
Intrasca,  p.  16.     Cleve,  Om  Svenska  och  Norska  Diat.,  p.  821. 

Common  in  the  same  localities  as  the  preceding,  with  which  it  is 
usually  mixed. 

Genus  III.    TEisAcrcLrs,  Ralfs. 

Frustules  united  in  parallel  filaments ;  .filaments  free ;  thickened 

2P2 


318  Proceedings  of  the  Royal  Irish  Academy, 

ends  of  the  diaphiagms  alternate ;  valves  much  expanded  in  middle  ; 
strongly  costate ;  costsB  pervious. 


Tetraeyclus  laeustris,  (Rails.)  Fresh  water. 
Middle  expansion  of  ^e  valve  rounded.  (Plate  29,  fig.  4.) 
Ralfs,  Ann.  Nat.  Hist.,  Vol.  xii.,  1843,  PL  ii.,  fig.  2.  Kutz.  Bac, 
p.  127,  T.  XXIX.,  fig.  70.  Rab.  Siissw.  Diat.,  p.  68,  T.  ix.,  fig.  1. 
Wm.  8m.,  B.  D.,  Vol.  ii.,  p.  38,  PI.  xxxix.,  fig.  308.  Ealfe,  in  Pritch, 
p.  806,  PL  viii.,  fig.  10,  and  PL  xi.,  fig.  24,  25.  Grunow,  Verhand 
der  K.  K.  Zool.  Bot.  GeseL,  Band  xii.,  1862,  p.  412.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  222. 

River  Erne,  Crossdoney,  Co.  Cavan.  Lake  near  Castlewellan,  Co. 
Down.  River  Bann,  Vomer's  Bridge,  Co.  Armagh.  Tonabrick  Moun- 
tain, Co.  Cork ;  Wm.  Smith. 

Teiraeyelus  emarginatus^  (Ehr.)     Fresh  water. 

**  Valves  constricted  towards  the  extremities,  which  arc  rounded 
and  8ub-apiculate ;  inflections  deeply  notched  or  emarginate ;  otherwise 
like  the  last  species." — Wm.  Smith. 

Wm.  Sm.  B.  D.,  VoL  ii.,  p.  38.  Ralfs,  in  Pritch.,  p.  806.  Grunow, 
Verhand.  der  K.  K.  Zool.  Bot.  GescL,  Band  xii.,  1862,  p.  412.  Rab. 
Fl.  Eur.,  sect.  1,  p.  302.  Cleve,  Om  Svenska  och  NorskaDiat,  p.  222. 
Smith  supposes  this  species  identical  with  Biblaiium  emarginatum, 
Ehr.  Mic.  T.  xxxiii.  2,  fig.  6.  On  his  authority  I  attribute  the 
species  to  Ehrcnberg. 

Gap  of  Dunloe,  KiQamey.  Wm.  Smitli.  This  species  is  extremely 
rare,  not  a  single  specimen  having  ever  come  under  my  notice  from 
any  locality  in  Ireland. 

Genus  IV.    Rhabdoxxka,  Eiitz. 

Stipes  ahoort;  diaphragms  numerous,  on  the  external  margin 
strongly  costate,  broad ;  extremity  of  the  valves  unstriate. 


Smith  alleges  that  in  this  genus  the  valves  have  a  median  Hnc,  a 
statement  which  does  not  appear  to  be  sustained  by  the  facts  of  the 
case* 

Rhdbdanema  areuatum,  (Lyngb.)    Marine. 

Frustules  short;  on  side  view  broadly  elliptical;  costate,  with 
monilif orm  strisD  interposed  between  the  costao  ;  striae  pervious ;  dia- 
X)hragms  numerous,  parallel,  with  a  single  foramen.     (PL  29,  fig.  5.) 

Kiiiz.  Bac,  p.  126,  T.  xviii.,  fig.  6,  who  states  that  the  species  is 


O'Mjsaila — RepoH  on  the  Liah  Diatomacece.  319 

identical  with  Diatoma  arcuatum,  Lvngbyfe,  Wm.  Sin.  B,  D.,  Vol.  ii., 
p.  34,  PL  xxxviii.,  flg,  305.  Ralls,  in  Pritch.,  p,  804.  Grunow, 
Verhand.  der  K.  K,  Zool.  Bot.  Gesel.,  Band  xii.,  p.  423.  Heiberg,  Do 
Danske  Diat.,  p.  70.  Eab.  t*!.  Eur.,  sect.  1,  p.  306.  Cleve,  Oni 
8ycnska  och  Nordka  Diat.,  p.  221. 

Salt  ditch,  near  Wexford.  Tacunjtslialie,  Co.  Wexford.  Malahide, 
Ballybrack,  Co.  Dublin.  Calnlough  Bay.  Sea-weeds,  Portrush, 
<7o.  Antrim.  Se^-weeds,  Dundalk,  Co.  Louth.  Sea-weeds  near 
Oalway  town.     Arran  Islands,  Co.  Galwlay. 

Ehahdonema  minutum,  (Kiitz.)    Marine. 

Yalvcs  small;  expanded  in  the  middle;  attenuated  towards  the 
rounded  ends ;  strieD  moniliform,  pervious ;  diaphragms  few ;  appa- 
rently alternate,  with  a  single  foramen. 

Kutz.  Bac.,  p.  126,  T.  xxi.,  fig.  2,  4.  Wm.  Sm.,  B.  D.,  Yol.  ii., 
p.  35,  PI.  xxxviii.,  fig.  306.  Ralfs,  in  Pritch.,  p.  804,  PI.  iv.,  fig.  41. 
Orunow,  Verhand.  der  K.  K.  Zool,  Bot.  Gesel.,  Band  xii.,  1862,  p.  423. 
Heiberg,  De  Danske  Diat.,  p.  70.  Rab.  PI.  Eur.,  sect.  1,  p.  306. 
Oleve,  Om  Svenska  och  Norska  Diat.,  p.  221. 

Sea-weeds,  Malahide;  on  piles  of  wooden  bridge,  Dollymount 
Strand,  Ballybrack,  Salt  Hill,  Co.  Dublin.  Sea-weeds,  Portrush. 
Lame,  Co.  Antrim.    T^umshane,  Co.  Wexford.    Dundalk,  Co.  Louth. 

Rhahdonema  adruUteum,  (Kiitz.)    Marine. 

Prufitules  very  large;  valves  narrow,  linear  elliptical;  stria5 
moniliform;  diaphragms  numerous,  not  so  wide  on  margins  nor  so 
strongly  costate  as  on  K.  arcuatum,  with  two  or  more  foramina. 

Kutz.  Bdc,  p.  126,  T.  xviii.,  fig.  7.  Wm.  8m.,  B.  D.,  Vol.  ii., 
p.  35,  PL  xxxviii.,  fig.  305  a,  b.  B^lfs,  in  Pritch.,  p.  805,  PI.  xiii., 
fig.  27.  Grunow,  Verhand.  der  K.  K.  2ool.  Bot.  Gesel.,  Band  xii., 
1862,  p.  424.  Bab.  Fl.  Eur.,  sect.  1,  p.  306.  Cleve,  Om  Svenska 
och  Norska  Diat.,  p.  221. 

Malahidc,  Co.  Dublin.  ''  Cork  Harbour.  Belfast  Bay,  near  Car- 
rickfergus."    Wm.  Smith. 

Genus  V.     Striatella,  Agardh. 

Frusiules  stipitate ;  stipes  long ;  valves  elliptical,  lanceolate,  with 
:q,  median  line,  without  central  or  terminal  nodule ;  stris  obsolete ; 
diaphragms  numerous,  on  front  view  linear,  unstriate,  strongly 
marked  at  one  end,  and  gradually  attenuated  towards  the  other ;  not 
reaching  the  entire  bread^  of  the  valves ;  arranged  alternately ;  on 
«ide  view  not  reaching  the  full  length  of  valve ;  open  the  greater  part 
<if  the  length. 


!\20  Proceedings  of  the  Royal  Irish  Academy. 

Striatella  unipunetata,  (Lyng.)  Marine. 
DiagnosiB  same  as  that  of  the  genus.  (Fl.  29,  fig.  6.) 
Eiitz.  Bac.,  p.  125,  T.  xviii.,  fig.  5,  who  considerB  the  fonn 
identical  with  Fragilaria  unipunetata,  Lyngbye.  Wm.  8m.,  B.  D., 
Vol.  ii.,  p.  3d,  PI.  xxxix.,  fig.  307.  Ralfs,  in  Pritch.,  p.  803,  PL  iv., 
fig.  40.  Grunow,  Yerhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862, 
p.  427.  Heiberg,  De  Danske  Diat.,  p.  72.  Rab.  Fl.  Eur.,  sect.  1, 
p.  307.     Cleve,  Om  Svenska  och  IS'orska  Biat.,  p.  222. 

Se&-weed8,  Bray,  Howth,  Salt  Hill,  Co.  Dublin.  Stomachs  of 
Ascidians,  Co.  Clare.  Sea-weeds,  Co.  Gal  way.  **  Larne  and  Belfast 
Bays,  Cork  Harbour,"     Wm.  Smith. 

Genus  YI.     Tessella,  Ehr. 

Frustules  stipitate,  stipes  short;  not  filamentous;  diaphragms 
apparently  reaching  not  further  than  the  middle  of  the  valve,  alter- 
nate, arched,  and  in  opposite  directions  on  the  opposite  sides  of  the 
frustule ;  external  edges  of  the  diaphragms  slightly  striate. 


Te»»ella  tnterruptay  (Ehr.)     Marine. 

Diagnosis  of  the  species  same  as  that  of  the  genus.  Of  the  side 
view  of  this  species,  I  have  never  been  able  to  obtain  a  satisfactory 
observation.     (PI.  29,  fig.  1,) 

Kiitz.  Bac,  p.  125,  T.  xviii.,  figs.  41,  2.  This  author  states  with 
hesitation  that  there  is  no  stipes  in  this  species,  as  also  does  Ralfs,  in 
Pritch.,  p.  804,  PI.  vii.,  fig.  5. — Striatella  interrupta,  Grunow,  Ver- 
hand,  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii.,  1862,  p.  427.  It  is  to  be 
noticed  that  this  species  cannot  be  confounded  with  StriatcUa  inter- 
rupta, as  described  and  figured  by  Heiberg,  De  Danske  Diat.,  p.  75, 
T.  v.,  fig.  15,  and  Rab.  Fl.  Eur.,  sect.  1,  p.  307. 

Sea- weeds,  Co.  Galway.  Sea- weeds,  Co.  Clare;  in  both  which 
localities  it  occurs  in  company  with  Striatella  unipunetata. 

Family  VII.    AMPHIPLETJRE^,  Kutz. 

Frustules  free;  lanceolate  on  side  view,  with  median  line  and  long 
narrow  end  nodules,  but  without  central  nodule,  and  exhibiting  a  sub- 
marginal  keel  at  each  side. 


Genus  I.     Ahphipleuba,  Kiitz. 

The  characters  of  this  genus  may  be  regarded  as  those  of  the 
family.     It  will  be  found  that  the  structure  of  the  frustules  in 


O'Meaba — Report  ofi  the  Irish  Diatomacea.  321 

this  genus  has  not  hitherto  heen  described  with  sufficient  accuracy 
for  their  satisfactory  diagnosis,  and  consequently  its  relations  with 
other  genera  have  been  very  variously  represented.  Kiitzing  in- 
cludes it  among  the  Naviculeae;  Smith  places  it  between  Amphi- 
prora  and  Navicula,  while  Ralfs,  Gninow,  and  Heiberg,  agree  in 
assigning  to  it  a  position  of  near  relationship  to  the  NitzschiesB. 
The  remarks  of  the  last  named  author  are  noteworthy: — "Amphi- 
pleura  is  a  genus  which  stands  in  need  of  a  more  precise  revi- 
sion. Grunow,  in  his  first  treatise,  placed  the  genus  in  the  group 
Surirellese,  with  which  it  has  no  very  close  relationship ;  but  sub- 
sequently this  author  established  the  genus  as  the  type  of  a  special 
group,  Amphipleureae,  and  at  the  same  time  gave  a  valuable  contribu- 
tion towards  a  more  precise  limitation  of  the  genus :  but  notwithstand- 
ing, much  remains  still  to  be  done.  I  have  placed  the  genus  with  the 
NitzschiecB,  because  Amphipleura  sigmoidea,  the  only  species  tho- 
roughly examined  by  me,  seems  to  agree  essentially  with  Nitzschia, 
and  in  fact  to  possess  the  same  unsymmetrical  relation  of  the  connect- 
ing membrane  with  the  front  view.  As  to  the  other  of  the  under- 
named species  (Amphipleura  pellucida),  I  have  not  as  yet  had  sufficient 
material  to  institute  a  more  exact  examination,  and  have  been  able 
only  to  satisfy  myself  as  to  its  identity  with  the  species  of  the  author 
named." — De  Danske  Diat.,  p.  116.  The  above  remarks  indicate  the 
source  of  the  confusion  which  exists,  namely,  the  supposition  that  the 
form  described  as  Amphipleura  sigmoidea  belongs  to  the  genus 
Amphipleura ;  I  regard  it  as  not  at  all  distinguishable  from  Nitzschia 
sigma.  Assigning  this  latter  form  to  its  proper  place,  we  have  a 
distinct  and  satisfactory  diagnosis  of  the  genus  Amphipleura,  founded 
on  the  presence  of  the  median  line  without  a  central  nodule,  and  the 
elongated  character  of  the  end  nodules,  as  well  as  the  presence  of  the 
submarginal  lines.  Beferring  to  the  last  named  peculiarity  of  struc- 
ture, Smith  notices  Ehrenberg's  ideal  transverse  section  of  the  frus- 
tule,  "  which  represents  the  ridges  as  springing  from  the  surface  of  a 
convex  valve,  having  between  them  a  depression  which  corresponds 
with  the  ordinary  median  line  of  the  NaviculaB,"  and  adds,  **  I  am 
unable  to  confirm  this  description." — ^B.D.,  Vol.  i.,  p.  45.  Grunow, 
however,  asserts  that  "  each  valve  has  three  k(?els ;  the  two  submargi- 
nal ones  springing  out  so  far  in  one  aspect  as  to  stand  on  the  valves  at 
right  angles  with  the  margin.  In  the  aspect  of  the  entire  frustule 
as  seen  from  the  side,  the  submarginal  keels  appear,  and  the  median 
line  forms ^;he  contour  of  the  valves." — ^Verhand.  der  K.  K.  Zool.  Bot. 
Qesel.  Band  xii.,  1862,  p.  467. 


Amphipleura pelltteida,  (Kiitz.)    Freshwater. 

Valves  narrow,  lanceolate ;  striss  obscure.     (PI.  29,  fig.  8.) 

Kiitz.  Bac.,  p.  103,  T.  iii.,  fig.  62,  T.  xxx.,  fig.  84.     In  neither  of 

these  figures  is  the  peculiar  form  of  the  end  nodules  noticed.    Wm. 

Sm.,  B.  B.,  Vol.  i.,  p.  45,  PI.  xv.,  fig.  127.     Here  the  valve  is  repro- 


322  Proceedings  of  the  JR&fol  Irish  Academy. 

sented  without  the  median  line,  and  having  a  lon^tudinal  row  ef 
moniliform  pnncta  interposed  between  the  margin  and  the  eabmar- 
ginal  keels :  the  latter  I  haye  neyer  been  able  to  detect.  Ralfs,  in 
Pritch.,  p.  783,  PL  iv.,  fig.  30,  PL  ix.,  fig.  140,  and  PL  xiii.,  fig.  1. 
Gmnow,  Vertiand.  der  K.  K.  Zool.  Bot.  Gesel.^  Bandzii.,  1862,  p.  468. 
Heiberg,  De  Danske  Diat.,  p.  117.     Eab.  FL  Eur.,  sect.  1,  p.  143. 

Limestone  quarry  near  Mullingar,  Co.  Westmeath.  Marl-pit,  Inch, 
near  Gorej,  Co.  Wexford.     Feighcullen,  Co.  Kildare. 

Ampkipleura  danica,  (Eiitz.)    Marine. 

Similar  to  the  preceding  in  all  respects,  save  that  it  is  shorter  and 
relatively  broader. 

Kiitz.  Bac.,  p.  103,  T.  xxx.,  fig.  38.  Balfs,  in  Pritch.,  p.  78S. 
Orunow,  Verhand.  der  K.K.  Zool.  Bot  GeseL,  Band  xii.,  1862,  pp.  468 
and  470.  Gmnow  is  uncertain  as  to  whether  the  median  line  has  the 
elongated  end  nodules ;  but  of  this  there  is  no  doubt,  my  specimens 
invariably  exhibiting  the  same :  and  he  seems  to  regard  the  species  as 
identical  with  Amphipleura  rigida,  Eiitz,  this  latter  being  in  fact  the 
same  as  Amphipleura  sigmoidea,  Wm.  Sm.,  and  belonging  not  to  the 
genus  Amphipleura,  but  to  Nitzschia. 

Stomachs  of  Ascidians,  Co.  Clare.  . 


Family  VIII.     NAVICULE^,  Kiitz. 

Frustules  oblong,  having  both  valves  furnished  with  a  median  line, 
central,  and  two  terminal  nodules. 


In  this  group  I  include  all  those  forms  with  symmetrical  frus- 
tules, more  or  less  oblong  elliptical  in  their  outline,  and  having 
both  valves  furnished  with  a  median  line,  also  with  a  central  and  two 
end  nodules  ;  quite  irrespective  of  their  mode  of  growth,  in  tubes,  stipi- 
tate,  or  free,  filamentous  or  simple.  So  limited,  Oomphonema,  and 
Cocconeis,  included  by  Heiberg  as  Naviculese  cuneatae,  are  necessarily 
excluded  on  account  of  the  unsymmetrical  structure  of  their  valves ; 
while  the  species  which  normally  occur,  surrounded  by  a  more  or  less 
amorphous  mass  of  gelatinous  investment,  as  Dickiea  and  Mastogloia, 
as  well  as  those  which  grow  in  tubes  more  or  less  composite,  as  Ber- 
kleya,  Colletonema,  Scliizonema ;  Boryphora,  which  is  stipitate,  Dia- 
desmis,  which  is  filamentous,  as  well  as  the  genera  which  grow  free, 
and  without  any  investment,  are  included,  because  their  frustules,  how- 
ever varying  in  minor  details,  ever  exhibit  the.same  general  features.  If 
Kiitzing,  Smith  and  others,  assigning  too  much  value  to  the  secondary 
modes  of  growth,  have  widely  separated  genera  which  are  intimately 
related  by  a  common  structure,  Heiberg  on  the  other  hand  regards  as 


O'MJKARA — Report  on  the  Irish  Diatomacm.  323 

of  little  or  no  significatioe  these  peculiarities  dE  growth,  which,  although 
flubordinate  to  the  general  st^cture  of  the  frustole's,  should  not  be 
overlooked.  These  differences,  as  they  occur  normally,  ai^  doubtless 
assignable  to  some  peculiarity  in  the  structure  of  the  plants  which 
regidarly  develop  them.  They  therefore  demand  the  careful  atten- 
tion of  the  students  of  nature,  and,  as  I  think,  ought  to  be  marked 
by  a  special  designatioti. 

(a).   Chlamydia — FrudideB  enveloped  in  a  more  or  less  definite  frond . 
Genus  1.     Mastogloia,  ^Ym.  Sihith  and  Thwaites. 

Mucous  frond  in  such  species,  as  have  been  observed  in  situ^  papil- 
late, the  frustules  imbedded  in  the  top  of  the  papillae ;  frustules  fur- 
nished with  narrow-marginal  silicioUs  plates  iiiterposed  between  the 
valve  and  the  connecting  band. 


Kiitzing,  (Bac.  p.  92,  T.  xxx.,  fig.  37,)  describes  a  form  Under  the 
name  of  NaVicula  meleagris,  which  evidently  belongs  to  this  genus. 
Thwaites,  Ann.  Nat.  Hist.,  March,  1848,  gives  a  description  of  another 
form  belonging  to  this  genus,  under  the  name  of  Dickiea  danseii,  but 
when  the  characteristic  difference  in  the  form  of  the  mucous  invest- 
ment was  pointed  out  by  Smith,  (B.  D.,  vol.  ii.,  p.  64),  he  estab- 
lished the  genus  Mastogloia  to  receive  a  new  form  discovered  by 
himself,  as  well  as  some  others  that  had  meanwhile  been  brought 
under  his  notice.  The  genus  therefore  may  in  some  measure  be 
attributed  to  Smith ;  the  more  so  because  he  first  seems  to  have 
noticed  and  described  one  of  the  most  important  features  in  the 
structure  of  the  frustule.  He  says,  "The  frustules  of  Masto- 
gloia are  notably  distinct  from  those  of  any  other  genera  of  the  tribe 
having  the  annulate  structure,  described  under  the  genus  Bhabdonema 
with  the  conspicuous  canaliculi  of  a  Surirella.  In  the  present  case, 
the  canaliculi  which  take  the  form  of  loculi  are,  howevpr,  formed 
differently  from  those  of  Surirella,  not  being  connected  with  the 
valve,  but  with  the  annulus,  which  projects  as  a  septum  into  the  body 
of  the  frustule."  And  again,  *'  Normally  the  annular  septum  extends 
only  partially  across  the  interior  of  the  frustule,  but  occasionally  the 
loculi  are  seen  to  reach  nearly  as  far  as  the  median  line  of  the  valve." 
— ^B.  D.,  Vol.  ii.,  p.  63.  In  reference  to  this  description,  Grunow  re- 
marks, **  I  have  been  unable  to  convince  myself  of  the  correctness  of 
8mith*s  supposition,  that  the  costse  which  according  to  him  form  dia- 
phragms are  attached  to  the  connecting  membrane.  After  numerous 
observations,  I  find  they  are  quite  analogous  to  the  costflB  of  other 
Diatoms,  and  are  an  inner  layer  of  the  silicious  plate  which  in  this  in- 
stance separates  itself  from  the  outer  layer  more  easily  than  in  other 
Diatoms.*^— Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860, 
p.  d74.  Heiberg's  views  on  the  subject  of  dispute  are  thus  ex- 
pressed :  "  Smith  on  the  contrary  took  an  erroneous  view  of  thd  genus 


324  Proceedings  of  the  Royal  Irish  Academy. 

as  sncli,  inasmtich  as  be  regarded  the  inner  layer  of  the  valTes  on 
which  the  characteristic  costas  are  situated  as  an  annnlus  or  dia- 
phragm of  the  same  structure  as  that  which  we  find  in  the  StriatellesD  : 
also  he  considered  the  costse  to  be  canaliculi,  which  does  not  corres- 
pond with  the  actual  facts  of  the  case.  Grunow  has  the  merit  of 
having  been  the  first  to  point  out  the  error  of  the  opinion  of  Smith 
above  referred  to." — De  Danske  Diat.,  p.  92.  Whether  the  plate  bear- 
ing the  loculi  is  more  intimately  associated  with  the  connecting 
membrane,  as  Smith  thought,  or  with  the  valve  itself,  as  Grunow  and 
Heibcrg  are  of  opinion  it  is,  this  is  certain,  so  far  as  my  observation 
extends,  that,  as  Grunow  remarks,  the  plate  seems  to  attach  itself  more 
frequently  to  the  valve  than  to  the  connecting  membrane ;  but  as  the 
valves  frequently  occur  without  the  plate,  and  the  plate  is  often 
found  detached,  i  am  disposed  to  consider  it  not  so  much  an  inner 
layer  of  the  silicious  epidcrm  as  a  separate  formation,  and  much  more 
intimately  related  to  the  diaphragms  of  the  Striatellece  than  to  the 
inner  layer  which  bears  the  costae  in  the  Epithemise.  Smith  describes 
the  loculi  as  opening  by  foramina  along  the  line  of  suture,  a  statement 
which  Balfs  repeats.  I  have  however  failed  to  notice  any  such  open- 
ings, the  plate  having  ever  appeared  to  be  perfectly  solid.  Inasmucli 
as  Thwaites  considered  the  occurrence  of  the  frustules  in  gelatinous 
cushions  the  distinctive  character  of  the  genus  Mastogloia,  and  other 
distinguished  writers  have  entertained  the  same  opinion,  Grunow' b 
remark  on  the  subject  is  deserving  of  attention  :  ''  Whether  the  species 
of  the  genus  Mastogloia  occur  invariably  in  a  gelatinous  investment,  is 
a  matter  concerning  which  I  am  very  doubtful,  as  in  a  fresh  collection 
I  observed  Mastogloia  Smithii  free,  while  I  found  no  specimens  in  a 
gelatinous  cushion" — Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x., 
1860,  p.  575.  However  this  may  be,  the  occurrence  of  the  plate  with 
loculi  in  the  perfect  frustule  is  a  mark  of  distinction  which  identifies 
the  genus.  Further,  it  was  considered  by  Grunow,  that  the  occurrence 
of  the  inner  layer  with  its  costate  striation,  so  different  from  the 
sculpture  of  the  valve,  constitutes  a  strong  bond  of  affinity  between 
Mastogloia  and  Cocconeis.  If,  however,  the  opinion  I  have  expressed  a» 
to  the  distinctness  of  the  plate  from  the  valve  be  correct,  this  resem- 
blance fails,  and  in  the  general  details  of  structure  the  two  genera  are 
widely  distinct.  The  process  of  reproduction  in  this  genus  has  been 
observed  by  Liiders  :  according  to  his  observations,  two  mother  cells, 
produce  two  auxospores.  Pfitzer,  Untersuchungen  iiber  Bau  und 
Entwicklung  der  Bacillanaceen,  p.  74,  remarks,  "that  in  this 
feature  the  genus  corresponds  with  the  Naviculeae,  and  not  with  the 
Cocconeidese  in  which  Grunow  placed  it ;  for  the  latter,  out  of  twa 
mother  cells,  develop  but  a  single  auxospore." 

Mastogloia  laneeolata,  (Thwaites.)    Marine  or  brackish  water. 

Yalves  lanceolate ;  marginal  plate  wide  at  middle,  and  gradually 
tapering  to  the  ends ;  loculi  narrow,  and  numerous ;  median  lin& 
slightly  undulate ;  strongly  marked  at  the  central  nodule,  and  greatly 


O'Meara — Report  on  the  Irish  Diatomacece.  326 

attenuated  towards  the  ends ;  striae  linear,  fine ;  slightly  radiate ;  not 
quite  reaching  the  median  line,  hut  terminated  by  two  strongly 
developed  sulci,  which  bend  in  slightly  towards  the  central  nodule  at 
cither  end,  leaving  a  narrow  lanceolate  space  about  the  median  line 
free  from  stiise. 

Smith  and  Grunow,  the  former  doubtfully,  regard  this  form  as 
identical  with  Navicula  meleagris,  Kiitz.Bac,  p.  92,  T.  xxx.,  fig.  37. 
Babcnhorst,  however,  regards  Eiitzing's  form  as  distinct  from  the 
present ;  and  in  this  I  am  disposed  to  agree  with  him,  as  I  have  seen 
specimens  exactly  corresponding  with  that  of  Eutzing,  and  as  I  think 
quite  distinct  from  Mastogloia  lanceolata. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  64,  PL  Uv.,  fig.  340.  The  figure 
and  description  are  correct,  as  far  as  they  go,  but  neither  the  longi- 
tudinal sulci  about  the  median  Hne,  nor  the  strisB  are  described. 
Half 8,  in  Pritch.,  p.  924.  Grunow,  Verhand.  der  Zool.  Bot.  Gesel., 
Band  x.  1860,  p.  576.  Heiberg,  De  Danske  Diat.,  p.  94.  Rab.  PL 
Eur.,  sect.  1,  p.  261.     Cleve,  Cm  Svenska  och  Norska  Diat.,  p.  230. 

Tacumshane,  Co.  "Wexford.  Lough  Gill,  Co.  Kerry.  Salt  marsh, 
Kilcool,  Co.  Wicklow.  Salt  marsh  near  the  town  of  Galway.  Dolly- 
mount  Strand,  Co.  Dublin. 

MoBtogloia  convergenSy  N.  S.     Marine  or  brackish  water. 

Valve  broadly  elliptical;  length  -0018;  breadth  -0008;  rounded 
at  ends ;  median  line  straight,  strongly  marked,  and  of  equal  breadth 
throughout ;  central  nodule  small  and  round :  marginal  plates  broad 
in  the  middle,  gradually  attenuated  towards  the  ends,  at  some  dis- 
tance from  which  they  bend  outwards ;  the  space  between  the  plates 
is  broadly  lanceolate  at  either  end,  and  narrower  in  the  middle,  where 
the  boundary  line  curves  very  gently  towards  the  margin;  loculi 
broader  than  in  the  last ;  striae  fine,  linear,  convergent  in  the  middle 
of  the  valve,  where  they  are  stronger  and  farther  apart,  and  for  the 
remainder  gently  radiate.     (PI.  29,  ^g,  9.) 

On  first  view,  this  form  might  readily  be  confounded  with  the 
preceding ;  but  the  more  carefully  it  is  examined,  the  more  apparent 
are  its  distinctive  characteristics.  In  its  outline,  it  is  broader  for  the 
length  than  Mastogloia  lanceolata ;  its  ends  are  broader,  and  more 
round.  In  the  latter,  the  loculi  are  more  numerous,  shorter  in  the 
middle,  and  gradually  diminishing  towards  the  ends ;  in  the  present 
case,  the  loculi  are  wider  in  the  middle,  and  suddenly  become  attenu- 
ated towards  the  ends.  The  longitudinal  sulci  near  the  median  line, 
8o  marked  a  feature  of  M.  lanceolata,  are  wanting  in  this.  In  M. 
lanceolata,  the  siaise  are  UDiformly  radiate ;  in  M.  convergens,  they 
are  convergent  in  the  middle,  and  for  the  rest  more  decidedly  radiate 
than  in  the  other. 

Salt  marsh  near  the  town  of  Galway.  Lough  Gill,  Co.  Kerrj^ 
accessible  to  the  tide. 


326  Pivceedings  of  t/ie  Itoyal  liish  Academy. 

Muto^hia  douii,  N.  S.     Maiine  or  brackish  water. 

Valve  somewhat  rhomboid ;  length  *0018 ;  breadth  *0008  ;  cnd^ 
narrow,  lanceolate ;  median  line  straight ;  central  nodule  very  small ; 
marginal  plates  wide  in  the  middle  for  a  short  space,  and  rapidly 
attenuated  long  before  reaching  the  ends;  loculi  generally  four  in 
number,  two  large  in  the  middle,  and  one  at  either  side  n^^itow,  at- 
tenuated; space  between  the  iimer  margin  of  plates  wide,  shaped 
somewhat  like  an  hour-glass,  with  pointed  ends ;  stris  fine,  linear, 
radiate,  reaching  the  median  line.     (PI.  29,  fig.  10.) 

Found  first  in  a  gathering  by  Rev.  Maxwell  H.  Close,  from  rock 
pools  in  the  bay  called  Lough  Kay,  between  Cahirciveen  and  t)oulus 
Head,  Co.  Kerry.  Lough  Gill,  Co.  Kerry.  Sea- weeds,  Giants'  Cause- 
way, Co.  Antrim. 

Moitogloia  portieranaf  (Grunow.)    Marine. 

Valves  narrow,  lanceolate ;  slightly  produced  at  the  apex ;  mar- 
ginal plates  narrow;  gradually  attenuated  towards  the  ends;  loculi 
numerous;  stris  very  obscure.     (PL  29,  fig.  11.) 

This  form  is  very  similar  in  some  respects  to  large  specimens  of 
Mastogloia  lanceolata,  but  difPers  in  many  details ;  it  is  longer,  and 
proportionately  narrower ;  the  sulci  at  either  side  of  median  line  in 
the  case  of  M.  lanceolata  are  absent  in  this;  the  apices,  too,  arc 
slightly  produced,  and  the  striae  much  finer  than  in  that  species. 
Grunow  states  that,  with  an  amplifying  power  of  400  times,  the  strias 
are  scarcely  noticeable ;  but  in  the  several  specimens  examined  by  mo 
with  a  one-eighth  objective  and  deep  eye-piece,  the  striae  could  not  be 
•discovered.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  xii. ; 
1863,  p.  157,  T.  iv.,  fig.  13.     Rab.  Fl.  Eur.,  sect.  1,  p.  236. 

It'rbto  stomachs  of  AscidialiR,  Houndstonc  Bay,  Co.  Galway. 

MMtogtoia  danseii^  (Thwaites.)    Marine  or  brackish  water. 

Valve  linear,  elliptical ;  broadly  rounded  at  ends ;  striae  reacliing 
the  median  line,  but  slightly  shortened  around  the  central  nodule ; 
radiate,  formed  of  close  puncta;  marginal  plates  on  inner  margin 
straight  till  near  the  ends,  where  they  are  suddenly  attenuated; 
loculi  numerous,  parallel;  space  between  the  plates  Harrow,  and 
slightly  expanded  at  the  ends. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  64,  Supp.  PI.  Ixii.,  fig.  388.  Ralfs, 
in  Pritch.,  p.  924,  PI.  xv.,  fig.  30.  Grunow,  Verhand.  der  K,  K. 
Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  676.  Rab.  Fl.  Eur.,  sect.  1, 
p.261. — Dickieadan8eii,Thwaites,  Ann.  Nat.  Hist.,  March,  1848,p.  171. 
Smith  seems  to  think  that  this  species  hardly  differs  from  Mastogloia 
lanceolata,  but  a  careful  consideration  of  the  two  forms  will,  I  think, 
prove  that  in  all  the  details  they  are  essentially  different. 

Tacumshane,  Co.  "Wexford.  Lough  Foyle,  Co.  Londonderry. 
Lame,  Co.  Antrim.     Salt  marsh,  Kilcool,  Co.  Wicklow. 


O'Meaba — Beport  on  the  IriA  Diaiamacew.  327 

Ma»ioghia  apictdata,  (Wm.  Sm.)    Marine. 

Yalyes  broadly  elliptical ;  slightly  produced  at  the  ends )  median 
line  fine,  with  two  sulci,  one  at  either  side,  and  very  close  to  it ; 
parallel  for  greater  part  of  length,  and  conyerging  towards  the  ends ; 
central  nodule  small ;  marginal  plates  narrow,  gradually  attenuated 
towards  the  ends,  where  they  suddenly  decrease  in  breadth ;  loculi 
numerous;  space  between  the  inner  margins  broadly  elliptical,  and 
slightly  expanded  at  the  ends ;  strise  fine,  closely  punctate,  slightly 
radiate. 

Wm.  8m.,  B.  B.  Vol.  ii.,  p.  65.  Supp.  PI.  Ixii.,  fig.  387.  Ralfs, 
in  Pritch.,  p.  925.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel., 
Band  x.,  1860,  p.  577,  T.  vii.,  fig.  9.     Rab.  Fl.  Eur.,  sect.  1,  p.  262. 

DoUymount  Strand,  Co.  DubUn.  Stomachs  of  Ascidians,  Bound- 
stone  Bay,  Co.  Galway. 

Mdstogloia  smithii,  (Thwaitcs.)     Fresh  or  brackish  water. 

Yalves  elliptical ;  frequently  produced  at  the  ends ;  marginal  platef^ 
relatively  broad ;  attenuated  at  tJie  ends ;  space  included  between  the 
inner  margins  narrow ;  slightly  expanded  at  the  ends ;  stria;  fine, 
linear;  slightly  radiate.     (PI.  29,  fig.  12.) 

This  form  varies  greatly  in  size  and  shape,  as  well  as  in  the  habitat. 
It  seems  essentially  a  fresh  water  form,  for  I  have  found  it  frequently 
in  localities  far  remote  from  marine  influences;  and  also  in  places 
where,  so  far  as  I  could  judge,  there  was  no  likelihood  of  mixture  of 
fresh  water  with  the  salt.  Under  the  circumstances,  I  was  anxious 
to  submit  the  forms  to  the  most  rigid  examination,  but  could  detect 
no  specific  difference  between  them.  Grunow  observes  that,  in  the 
specimen  that  come  under  his  notice,  there  was  even  a  tolerably  wide 
transversely  expanded  central  nodule,  which  he  considers  should  be 
established  as  the  characteristic  distinction  between  this  species  and 
Mastogloia  lanceolata.  I  may  mention  that  this  feature,  though 
frequently  noticeable,  is  not  of  universal  occurrence. 

Wm.  Sm.,  B.D.,  Vol.  ii.,  p.  65,  PL  liv.,  fig.  341.  Ralfs,  in  Pritch., 
p.  925.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860, 
p.  575,  T.  vii.,  t^.  11.  Bab.  Fl.  Eur.,  sect.  1,  p.  261.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  230. 

Tacumshane,  Co.  Wexford.  Lough  Gill,  Co.  Kerry.  Eilcool, 
Co.  Wicklow.  Newtownlimavady,  Co.  Derry.  In  all  which  gatherings 
there  was  a  mixture  of  fresh  and  brackish  forms.  Tide  pool,  Greystones, 
Co.  Wicklow,  where  the  forms  were  mostly  marine.  Lough  Corrib, 
Co.  Gtdway,  wholly  free  from  marine  influence. 

Var.  capitala,  (Wm.  Sm.)     Fresh  water. 

Agreeing  witii  the  typicflJ  form,  only  that  the  produced  ends  are 
capitate ;  the  striae,  also,  which  are  similarly  arranged,  may  easily  bo 
resolved  into  minute  dots. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  65,  PI.  liv.,  fig.  341  b.     In  all  pro- 


328  Proceedings  of  the  Royal  Irish  Academy. 

bability,  tliis  is  identical  with  the  form  described  by  GreTille,  Q.  J.  M.  S.^ 
October,  1862,  p.  235,  PL  x.,  fig.  11 ;  although  that  author  remarks 
that  in  his  form  the  striae  were  much  more  obscure  than  in  the  form 
figured  by  Smith  as  above. 

Lough  Corrib,  Co.  Gal  way,  mixed  with  the  t3rpical  form. 

Mastogloia  grevillii^  (Wm.  8m.)    Fresh  water. 

Valve  linear ;  cuneate  at  the  obtuse  extremities ;  marginal  plate 
nearly  linear  on  the  inner  margin,  suddenly  attenuated  towards  the 
ends;  loculi  numerous;  striae  fine,  linear,  radiate,  shortened  at  the 
central  nodule,  so  as  to  give  a  stauro-form  appearance  to  the  valve. 

Wm.  Sm.  B.  D.  Vol.  ii.,  p.  64,  Supp.  PI.  Ixii,  fig.  389,  Ralfs,  in 
Pritch.,  p.  925.  Grunow,  Vcrhand.  der  K.  K.  Zool.  Bot.  G^sel., 
Band  x.,  1860,  p.  575.  Heiberg,  De  Dansko  Diat.,  p.  94.  Bab.  Fl. 
£ur.,  sect.  1,  p.  260. 

Kilcool,  Co.  Wicklow.  Lough  Neagh,  Co.  Antrim.  Ballyshannon, 
Co.  Donegal.     Carrickhugh,  Co.  Derry. 

Mastogloia  eostata,  N.  S.     Fresh  water. 

Valve  linear ;  cuneate  at  ends ;  length  '0013,  breadth  -0005  ;  mar- 
ginal plates  broad,  on  inner  margin  perfectly  linear  till  near  the  ends, 
where  they  very  slightly  expand,  in  shape  of  a  spear  head ;  loculi 
numerous ;  striae  strongly  costate,  converging  in  the  middle,  and  for 
the  rest  radiate ;  shortened  at  the  central  nodule.     (PI.  29,  fig.  13.) 

In  shape  and  size,  this  form  is  so  like  Mastogloia  grevillii  that  it 
might  easily  be  confounded  with  it ;  but,  however,  on  closer  investi- 
gation it  will  appear  quite  distinct.  In  M.  grevillii,  the  fine  linear 
striae  can  by  proper  focusing  be  easily  seen  along  with  the  loculi  of 
the  marginal  plate.  Li  the  present  species,  either  from  the  convexity 
of  the  valve,  or  the  coarseness  and  closeness  of  the  costate  striae,  or 
perhaps  owing  to  both  these  circumstances,  the  plates  are  not  easily 
detected,  except  at  the  inner  margin,  where  their  boundary  may  bo 
detected  by  the  clear  intervening  space  into  which  the  ends  of  the 
strong  costae  are  seen  to  project. 

On  a  moist  rock,  Ballyshannon,  Co.  Donegal. 

Genus  II.     Dickieia,  Berkeley. 

Frond  flat,  leaf -like ;  unbranched ;  frustulcs  scattered  without  re- 
gular arrangement. 


Smith  attributes  this  genus  to  Ealfs ;  but  Balfs  himself  ascribes  it 
to  Berkeley.     It  is  adopted  by  Kiitzing,  Smith,  Gninow,  and  Ba-ben- 


O'Meara — Report  on  the  Irish  DiatoniacecB,  329 

hont,  but  Heiberg  rejects  it  as  being  uimecessaryy  the  fonns  being,  as 
he  thinks,  ranged  properly  with  the  Naviculae. 

Dickieia  ulvoideSf  (Berk.),  Marine. 

Gelatinous  frond,  more  or  less  perfectly  ovate ;  entire,  and  having 
a  distinct  pedicel;  valves  linear,  elliptical ;  centnl  nodule  transversely 
dilated;  strise  fine,  parallel.     (PI.  29,  fig.  14.) 

Berkeley  and  Ealfs,  Ann.  Nat.  Host.,  Series  1.,  Vol.  xiv.,  PI.  ix., 
Kiitz.  Bac.,  p.  119.  Wm.  Sm.,  B.P.,  Vol.  ii.,  p.  66,  PL  liv.,  fig.  342. 
Kalfs,  in  Pritch.,  p.  925,  PL  xv.,  fig.  31.  Bab.  PL  Eur.,  sect.  1, 
p.  264. 

Greystones,  Co.  Wicklow. 

Dickieia  ^nata,  (Ealfs),  Marine. 

Frond  lasciniated ;  valves  narrow,  elliptical ;  strias  fine,  parallel ; 
nodule  small,  round. 

Balfs.  Ann.  Nat.  Hist.,  2nd  Series,  Vol.  viii.,  PL  v.,  fig.  6.  Ealfs, 
in  Pritch.,  p.  925.  Wm.  Sm.,  B.  D.  Vol.  ii.,  p.  66,  PL  liv.,  fig.  343. 
Rab.  Fl.  Eur.,  sect.  1,  p.  264. 

On  piles  of  the  wooden  bridge,  Dolljrmount  strand  ;  Wooden  piles 
on  strand,  Clontarf ;  Sea-weeds,  Malahide ;  Ireland's  eye ;  Eock-pools, 
Ballybrack,  Co.  Dublin :  in  the  last  named  locality  it  occurs  in  greatest 
abundance.     Lame,  Co.  Antrim. 

Genus  III.     Colletonema,  De  Breb. 

Gelatinous  frond  filiform,  simple  or  sparingly  divided  at  the  ends. 


The  first  known  forms  of  this  genus  were  discovered  by  Thwaites, 
smd  published  by  him  in  Ann.  Hist.,  March,  1848,  under  the  generic 
name  of  Schizonema.  De  Brebisson  subsequently  separated  these 
forms  from  Schizonema,  and  instituted  the  present  genus  for  their 
reception ;  the  distinguishing  characters  being  their  fresh  water  habi- 
tat, and  the  simple  tubular  frond.  Whatever  value  may  attach  to 
the  latter  peculiarity,  the  former  is  utterly  untenable  as  a  generic  dis- 
tinction. Smith  alleges  that  in  this  genus  the  frustules  are  more 
firmly  silicious  than  in  Schizonema,  a  statement  I  cannot  corroborate ; 
but  even  though  it  admitted  of  no  doubt,  this  fact  coidd  scarcely  be 
regarded  as  a  sufficient  generic  distinction.  Eabenhorst,  Siissw.  Diat., 
p.  51,  who  himself  observed  none  of  the  species,  adopts  the  genus, 
characterising  it  by  the  fact  of  the  frustules  occurring  in  rows  within 
a  structureless  gelatinous  investment.  Ealfs  adopts  Smith's  definition, 
but  doubts  "if  any  of  the  above  characters  sufficiently  distinguish 
Colletonema  from  tke  allied  genera,"  in  Pritch.,  p.  926.  Grunow's 
observations  on  the  genus  are  noteworthy;  he  says:    "The  genus 


330  Proceedings  of  ike  Royal  Irisli  Acadetny. 

Colletonema  is  in  a  twofold  aq>ect  uncertainly  founded.  On  the  one 
hand,  it  can  scarcely  be  rightly  separated  from  Schizonemo,  in  which 
Bmall  forms  occur  in  simple  sheaths,  and  on  the  other  hand  its  separa- 
tion from  Navicula  is  very  uncertain.  It  appears  to  me  that  many 
species  of  Naviculffi  may,  under  certain  conditions,  occur,  as  well  in 
gelatinous  masses  as  inclosed  in  gelatinous  tubes,  and  two  of  the 
forms  which  I  haTe  with  some  hesitation  placed  in  this  genus  appear 
to  me  to  confirm  this  impression."  Farther  on,  in  his  observations  on 
Colletonema  neglcctum,  he  remarks  :  ''  I  once  observed  this  species  in 
an  unused  mill-stream  in  which  Navicula  gracilis  occurred  in  uncommon 
abundance,  and  for  the  most  part  certainly  in  a  free  state ;  very  fre- 
quently also  were  found  gelatinous  tubes  filled  with  perfect  frustules 
of  Nayicula  gracilis,  just  as  Smith  has  described  it,  and  also  very  un- 
frequently  bands  consisting  of  double  rows  of  the  same  Navicula 
without  any  sheaths ;  nor  could  I  by  the  most  careful  examination  dis- 
criminate between  these  forms  and  those  of  Navicula  gracilis  from 
other  localities,  where  no  gelatinous  tubes  were  discovered." — Verhand. 
der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  pp.  670,  571.  Theso 
observations  coincide  with  the  supposition  of  Wm.  Smith,  that  ''  Fin- 
nularia  radiosa  may  be  merely  a  free  state  of  Colletonema  neglectum 
and  Navicula  crassinervia,  the  same  condition  of  Colletonema  vulgare."^ 
B.  D.,  Vol.  ii.,  p.  69.  I  take  the  opportunity  of  remarking  that,  in  a 
gathering  made  by  me  from  Lough  Aron,  on  the  summit  of  the  Slieve- 
amoran  mountain,  Co.  Antrim,  in  the  summer  of  1872,  Navicula  rhom- 
boides  occurred  in  great  abundance  ;  some  of  the  forms  were  free  and 
active,  others  were  inclosed  in  gelatinous  tubes,  invariably  arranged  iu 
single  files,  and  by  no  means  uncommonly  the  frustules  were  seen  in 
long  files,  attached  apparently  one  to  another  by  the  ends,  without  tho 
slightest  appearance  of  tubes,  just  as  in  Grunow's  case  of  Navicula 
gracilis,  llabonhorst  restores  the  species  of  this  genus  to  Schizonema ; 
and  Hciberg,  rejecting  the  generic  distinction  founded  on  the  gelati- 
nous tubes  in  which  the  frustules  are  invested,  unites  them  with 
Navicula. 

Eeproduction  has  been  observed  by  Thwaites  in  the  case  of  Colle- 
tonema subcoherens;  he  says:  **Thc  Sporangia  of  this  species  are 
produced  by  the  conjugation  of  a  pair  of  frustules  outside  the  filaments  ; 
but  sporangiol  frustules  are  frequently  found  in  a  filament  intermixed 
vsdth  ordinary  frustules,  from  which  they  differ  only  in  size." — Ann. 
Nat.  Hist.,  March,  1848.  Pfitzcr  superadds,  that  ''two  cells  produce^ 
two  auxospores." — Untcrsuchungen,  p.  73. 

Colletonema  eximium,  (Thwaites),  Fresh  water. 

Frond  filiform,  frustules  arranged  in  one  or  more  rows;  valve- 
sigmoid,  striae  fine,  parallel. 

Kab.  Sussw.  Diat.,  p.  51.  Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  69,  PI.  Ivi., 
fig.  350.  Ralfs,  in  Pritch.,  p.  926,  PL  viii.,  fig.  43.  Grunow,  Ver- 
hand. der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  573,  who  remarks^ 
regarding  this  species :  '4t  must  either  be  transferred  to  Pleurosigma^ 


O'Meara — Report  on  the  Irish  I>iatamace€e.  331 

or  a  new  genus  estabKshed  to  receive  it." — Schizonema  eximimn,  • 
Thwaites,  Ann.  Nat.  Hist.,  March,   1848.     Eab.  Fl.  Eur.,  sect.  1, 
p.  266. — Gloionema  sigmoides,  Ehr.  Abh.,  1845,  p.  78. — Encyonema 
aigmoides,  Kiitz.  Alg.,  p.  62. — Endosigma  eximium.  Bo  Br^b. 

Tacumshane,  Co.  Wexford.  Near  Eailway  station,  Newtown- 
limayady,  Co.  Derry. 

CoUetonema  wdgare,  (Thwaites).     Fresh  water. 

Frond  occasionally  divided;  frustides  elliptical,  lanceolate,  strife 
very  fine. 

In  Smith's  figure  the  striae  are  described  as  radiate,  but  I  have 
never  been  able  to  resolve  them. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  70,  PI.  Ivi.,  t%,  351.  Grunow, 
Verhand.  dor  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  572.  Balls, 
in  Pritch.,  p.  926. — Schizonema  vulgare,  Thwaites,  Ann.  Nat.,  Hist., 
2nd  Series,  Yol.  i.,  p.  10,  PI.  xii.,  fig.  H.  Bab.  Fl.  Eur.,  sect.  1, 
p.  265. — Navicula  vulgaris,  Heiberg,  De  Danske  Diat.,  p.  83. 

Carrickmacreilly  Mountain  near  Glanealy,  Wicklow:  the  species  is 
very  uncommon. 

CoUetonetna  negJectum,  (Thwaites.)     Fresh  water. 

Frond  slightly  divided ;  frustules  closely  packed ;  elliptical,  lan- 
ceolate ;  extremities  obtuse ;  striae  finely  costate,  radiate.  (PI.  29, 
fig.  15.) 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  70,  PI.  Ivi.,  fig.  352.  Balls,  in  Pritch., 
p.  926.     Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x., 

L571. — Schizonema  neglectum,  Thwaites,  Ann.    Nat.  Hist.,    2nd 
ries.  Vol.  i.  p.  11,  PI.  xii.,  J.     Bab.  Fl.  Eur.,  sect.  1,  p.  265. 

Genus  IV.    B£bx£leya,  Greville. 
Frond  branched,  the- branches  springing  Irom  a  basal  tubercle. 


Most  authors  adopt  this  genus,  but  Heiberg  rejects  it  as  unneces- 
sary, and  includes  the  species  under  Navicula. 

Berkeleya  fragilis,  (Greville.)     Marine. 

Frustules  closely  packed  in  the  tubes.  Valves  elliptical,  lanceo- 
late, broadly  rounded  at  the  ends.     Striae  obscure.     (PI.  29,  fig.  16.) 

Grev.  Scot.  Crypt.  Flora,  tab.  294.  Do.  Brit.  Flora,  p.  41 6.  Kails, 
Ann.  Nat.  Hist.,  1st  Series,  Vol.  xvi.,  PL  iii.,  fig.  2.  Do.,  in  Pritch., 
p.  926.  Kutz.  Bac,  p.  109.  Wm.  Sm.,  B.D.,  Vol.  ii.,  p.  67,  PI.  liv., 
fig.  344.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x., 
1860,  p.  512.  Bab.  Fl.  Eur.,  sect.  1,  p.  264. — Navicula  Iragilis,  Hei- 
berg, De  Danske  Diat.,  p.  84.    Bangia  micans,  Lyngbye,  Tent.  Hydro- 

X.  X.  A.  PBOC,  6BB.  n.,  VOL.  H.,  tCIBNOl.  2  Q 


332  Proceedings  of  tlie  Royal  Irish  Academy. 

phyt.,  p.  84.    This  last  Bynonym  is  given  on  the  authority  of  Heibeig, 
who  had  the  opportunity  of  inspecting  authentic  specimens. 

Cork  Harbour,  Wm.  Smith.  Rock-pool,  Salt  Hill,  Co.  Dublin. 
Coast  of  Galway,  from  collections  by  M'Calla,  in  the  Herbarium, 
Trinity  College,  Dublin. 

Genus  Y.    Schizonema,  Agardh. 

Frond  usually  much  divided.  Frustules  arranged  in  one  or  more 
files  within  the  gelatinous  tubes  which  constitute  the  frond. 


Smith  remarks  justly  that  ''  the  fronds  in  this  extensive  genus 
were  amongst  the  earliest  Diatomaceous  organisms  recognised  by 
naturalists,  and  have  been  the  perplexity  of  all  subsequent  observers." 
Nor  is  this  to  be  wondered  at,  when  the  difficulties  attendant  on  their 
examination  are  taken  into  consideration.  The  frustules  enveloped 
in  the  fronds  are  generally  minute,  so  that  even  though  they  were 
free  it  would  be  no  easy  matter  to  examine  them  satisfactorily,  and 
the  difficulty  is  much  enhanced  by  the  intervention  of  the  fronds  as 
well  as  by  the  manner  in  which  the  frustules  are  packed  within  them. 
Kiitzing  attempted  to  arrange  the  species  on  the  basis  of  the  charac^ 
ters  of  the  fronds,  but  with  how  little  success  the  student  will  be 
convinced  who  endeavours  to  make  himself  master  of  the  subject  by 
the  aid  of  his  minute  descriptions,  and  of  his  very  indefinite  figures. 
Heiberg  falls  into  a  mistake  the  very  opposite  to  that  of  Kiitzing — 
discarding  from  consideration  not  only  the  characters  of  the  fronds  in 
the  various  species,  but  regarding  the  fact  of  the  frustules  being  normally 
incased  within  fronds  as  an  unreliable  generic  distinction,  and  so  he 
ranks  the  species  under  the  genus  Navicula.  De  Br^bisson  had  ob- 
served that  "  the  greater  part  of  the  species  needed  reconsideration, 
and  to  be  studied  with  reg£u:d  to  the  character  of  the  frustules."  and 
Smith,  with  his  characteristic  sagacity,  taking  this  hint,  at  the  same 
time  not  overlooking  any  reliable  character  exhibited  by  the  fronds, 
dispelled  the  confusion  which  had  hitherto  existed,  and  reduced  the 
species  into  an  order,  which  seems,  all  the  circumstances  considered,  to 
admit  of  little  improvement. 

As  to  the  mode  of  reproducing  the  sporangia  in  the  genus,  opinions 
differ,  as  the  following  extract  from  Pfitzer  will  sufficiently  show : — 
**In  Schizonema  Grevillii,  according  to  Smith,  a  single  mother-cell 
produces  a  single  auxospore,  while  according  to  Liiders  this  occurs 
but  seldom,  namely,  when  one  auxospore  becomes  defunct ;  usually,  on 
the  contrary,  two  cells  co-operate,  and  form  two  auxosxK>res.  The 
development  of  the  latter  occurs  outside  the  tubes  in  a  large  and  fine 
mucous  investment.  The  mode  of  proceeding,  according  to  Liiders,  is 
that  each  mother-cell  divides  itsefi,  and  the  halves  unite  in  pairs. 
However,  in  other  forms  in  which,  according  to  Liiders,  a  similar 


O'Meara — Report  on  the  Irish  Biaiomacece.  333 

state  of  things  occnrs,  I  haye  not  found  this  view  confirmed.  So  that 
probably  Schizonema  does  not  differ  in  this  respect  from  the  rest  of 
the  Navicnlse." — ^Untersuchungen  iibcr  Eau  nnd  I^twicklung  der  Bac- 
illariaceen,  p.  73. 

(t)  Ihistules  with  parallel  atrice. 

Schizonema  emei^erum,  (Wm.  Sm.)    Marine. 

''Frond  filiform;  filaments  implicate  below^lECc  aboye,  much 
^ctirided.  Trastulcs  crowded.  Valves  with  a  distinct  staurosi  lanceolate, 
acute"  (Wm.  Smith)  on^side  view ;  on  front  view  wider  in  the  middle 
than  at  ends.     Striae  distinct,  close,  linear.     (PI.  29,  fig.  17.) 

In  Smith's  figure,  the  strisB  are  described  as  slightly  radiate,  but 
in  my  specimens,  I  find  them  parallel. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  74.,  PI.  Ivi.,  fig.  354,  and  PI.  Ivii., 
fig.  356.  RaKs,  in  Pritch.,  p.  928.  Rab.  PI.  Eur.  sect.  1,  p.  266. 
— Stauroncis  cmcigera,  Heiberg,  De  Donskc  Diat.,  p.  88. 

Tacumshane,  Co.  Wexford.  Malahide,  Portmamock,  Salt-hill, 
Co.  Dublin.    Rostrevor,  Co.  Down.    Lough  Gill,  Co.  Kerry. 

Sehtionema  smithii,  (Agardh.)    Marine. 

''  Prond,  filiform,  robust,  simple  below,  much  divided,  fasciculated 
and  fastigiate  above.  Erustulcs  in  numerous  closely  set  files.  Valves 
clliptico-lanceolate,  acute." — ^Wm.  Smith.  To  which  I  would  add,  stria?, 
obvious,  extending  to  median  line.  Front  view  of  frustule  regularly 
quadrangular.     (PI.  29,  fig.  18.) 

Agaidh.  Conspectus,  p.  18.  Kiitz.  Bac,  p.  114,  T.  xxvii.,  fig.  5. 
Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  75,  PI.  Ivii.,  fig.  362.  Rab.  Fl.  Eur., 
sect.  1,  p.  269. — ^Micromega  Smithii,  Ralfs,  in  Pritch.,  p.  930. 

Howth,  Salt  Hill,  Malahide,  Co.  Dublin.     Sea  coast,  Co.  Antrim. 

Schizonema  ditergene,  (Wm.  Sm.)    Marine. 

**  Frond,  simple  below,  sparingly  divided,  or  by  cohesion  irregu- 
larly submembranous  above ;  ultimate  ramuli  short,  obtuse." — ^Wm. 
Smith.  Valve,  shorter  and  wider  than  the  last,  and  more  rounded  at  the 
ends^    Striee  fine,  linear,  reaching  the  median  line. 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  76,  PI.  Ivii.,  fig.  363.  Rab.  Fl.  Eur. 
sect.  1,  p.  269.— Micromega  divergcns,  Ralfs,  in  Pritch.,  p.  931. 

Besides  the  locality  named  by  Wm.  Smith,  Lame  Lough,  where  it 
was  collected  by  Dr.  Dickie,  this  species  has  been  gathered  by  myself 
at  Malahide  and  Salt-hill,  Co.  Dublin ;  and  by  Dr.  David  Moore,  at 
Carrickfergus  and  Camlough  Bay,  Co.  Antrim. 

Schizonema  mucosum,  (Kiitz.)    Marine. 

**  Frond  filiform,  gelatinous,  simple  below,  by  cohesion  sub-mem- 

2Q2 


334  Proceedings  of  the  Royal  Irish  Academy. 

branous  above.  Margin  irregularly  ramulous.  Frustules  in  files,  few, 
sub-distant.  Valve  elliptical,  delicately  striata."  Wm.  Smith.  Not 
unlike  the  last,  except  that  it  is  more  delicately  striate,  shorter,, 
broader,  and  more  rounded  at  ends. 

Kiitz.  Bac.,  p.  115,  T.  xxvi.,  fig.  9.  Wm.  Sm.,  B.  D.,  Vol.  ii.^ 
p.  75,  Fl.  Ivii.,  fig.  360.  Rab.  Fl.  Eur.,  sect.  1,  p.  268. — ^Micromega 
mucosum,  Ralfs,  in  Pritch.,  p.  933. 

"With  seaweeds,  Galway,  Dr.  David  Moore.  Malahide,  Howth,  Co, 
Dublin. 

Sehifumema  ramosisHtnutn,  ^Agardh.)    Marine. 

**  Frond  filiform,  much  divided  from  the  base,  and  irregularly  sub- 
membranous  by  cohesion  above.  Hamuli  short,  obtuse.  Frustules 
numerous,  in  closely  packed  files.  Valves  clliptico-lanceolate,  acute." — 
Wm.  Smith.     Strio)  ^o,  linear. 

Agardh.  Syst.,  p.  il.  Harvey's  Manual,  p.  210,  who,  according 
to  Smith,  had  the  opportunity  of  inspecting  authentic  specimens. 
Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  78,  PL  lix.,  fig.  369.  Rab.  Fl.  Eur. 
p.  272. — Micromega  ramosissimum,  Agardh.  Consp.,  p.  22.  Ralfs,  in 
Pritch.,  p.  934. 

Near  Lame,  Camlough,  Co.  Antrim,  collected  by  Dr.  David 
Moore. 

(ft).  Frustules  having  radiate  stria. 

Schizofiema  greviUiif  (Agardh.)     Marine. 

**  Frond  filiform,  much  divided  from  the  base.  Ultimate  ramuli 
acute,  larger  divisions  with  several  files  ;  ultimate  ramuli  with  a  single 
file  of  frustules.  Valve  lanceolate." — Wm.  Smith.  Stria)  fine,  gently 
radiate.  On  the  front  view,  frustules  are  very  wide,  quadrangular. 
The  side  view  appears  nearly  as  far  as  the  median  line.  The  central 
nodule  thus  seen  is  depressed.  The  connecting  band  exhibits  longitu- 
dinal lines.     (PI.  29,  fig.  19.) 

Agardh.  Conspect.,  p.  19.  Eiitz.  Bac,  p.  114,  T.  xxvi.,  fig.  4., 
T.  v.,  fig.  1.  Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  77,  PI.  Iviii.,  fig.  364. 
Ralfs,  in  Pritch.,  p.  928.  Rab.  Fl.  Eur.,  sect.  1,  p.  267. — Schizonema 
quadripunctatum,  Harvey's  Manual,  p.  214. 

Lame,  Carrickfergus,  Co.  Antrim,  collected  by  Dr.  David  Moore. 
Malahide,  Merrion,  Co.  Dublin.  River  Nannywater,  near  Laytown, 
Co.  Meath. 

Schizonema  helmintosum,  (Chauvin.)    Marine. 

*'  Frond  filiform,  or  by  cohesion  irregularly  sub-membranous ;  much 
and  irregularly  divided ;  ultimate  divisions  short,  abrupt." — Wm.  Smith. 
Frustules  linear,  elliptical,  sometimes  sharp,  sometimes  more  rounded 


O'Meara — Report  on  the  Irish  DiatonmeecB.  335 

4it  tho  ends.  StiisB  fine,  obBcnrely  punctate,  convergent  about  the 
central  nodule,  and  for  a  considerable  distance  from  it,  towards  tho 
ends  straight  and  radiate. 

Agardh.  Conspect.,  p.  20.  Grev.  Brit.  Flora,  p.  412.  Harvey's 
Manual,  p.  210.  Kiitz.  Bac.,  p.  114,  T.  xxvii.,  fig.  6.  Wm.  Sm., 
B.  D.,  VoL  ii.,  p.  74,  PI.  Ivi.,  fig.  355.  Rab.  Fl.  Eur.,  sect.  1,  p.  268.— 
Micromega  helmintosum,  Balfs,  in  Pritch.,  p.  830. 

Howth,  Malahide,  Co.  Dublin.  Camlough  Bay,  collected  by  Dr. 
David  Moore. 

Sehizonetna  comoides,  (Agardh.)     Marine. 

''Frond  filiform,  simple  below,  much  divided  and  fasciculated 
tibove.  Frustulescrowded." — Wm.  Smith.  Fruetules  small,  length  about 
•0010,  somewhat  rhombic  on  front  view,  rounded  slightly  at  the  ends. 
Strife  strong  and  distant  at  centre,  finer  and  closer  towards  the  end ; 
on  front  view  linear,  in  outline  rounded  at  ends. 

Agardh.  Conspect.,  p.  19.  Harvey's  Manual,  p.  213.  "Wm.  Sm., 
B.  D.,  Vol.  ii.,  p.  75,  PI.  Ivii.,  fig.  358.  Rab.  Fl.  Eur.,  sect,  i.,  p. 
268. — Schizonema  araneosum,  Kiitz.  Bac,  p.  113,  T.  xxiv.,  fig.  2,  T. 
XXV.,  fig.  ix. — Micromega  comoides,  Balfs,  in  Pritch.,  p.  934. 

Camlough  Bay,  Co.  Antrim,  collected  by  Dr.  David  Moore.  Howth, 
Malahide,  Co.  Dublin. 

Schizonema  parasiticum^  (Harvey.)    Marine. 

"  Frond  capillary,  branched,  filaments  slightly  cohering  above. 
Bamuli  short,  patent.  Mucus  often  rugose.  Frustules  crowded  in  files, 
more  or  less  distant.  Valves  elliptico-laQceolate,  acute.  Length  of  frond 
5"  ;  length  of  frustule  -0011 ;  breadth  of  valve  -0002."— Wm.  Smith. 
8tnm  extremely  fine.    Frustule  on  front  view  quadrangular. 

Harvey's  Manual,  p.  213.  Wm.  Sm.  B.  D,.  Vol.  ii.,  p.  79,  PI.  lix., 
fig.  37.  liab.  Fl.  Eur.,  p.  273. — Micromega  parasiticum,  Kiitz;  Bac, 
p.  116,  T.  xxvii.,  fig.  2.     Ralfs,  in  Pritch.,  p.  932. 

Makhide,  Salt  Hill,  Co.  Dublin. 

Sehizonenia  laeiniatum,  (Harvey.)    Marine. 

''Frond  filiform,  much  branched,  filaments  often  adhering  into 
rope-like  tufts.  Bamuli  very  long.  Frustules  numerous,  crowded  in  irre- 
gular files.  Valves  elliptical,  somewhat  acute.  Length  of  frustule  -00 1 8 ; 
breadth  of  valve  -00035." — Wm.  Smith.  Valves  striate ;  striae  punctate, 
gently  radiate.  On  front  view  frustules  broader  at  middle  than  at 
ends,  ends  rounded  off;  side  view  coming  largely  into  sight  when 
observed  in  front,  the  inner  margins  nearly  meeting  the  connecting 
membrane,  and  at  the  ends  receding  therefrom. 

On  careful  inspection  of  authentic  specimens  of  Schizonema  impli- 
«atum  (Harvey),  I  fijid  the  frustules  on  side  and  front  view  so  like  one 


336  Proceedings  of  the  Royal  Irish  Academy. 

another  in  all  respects  that,  judging  from  the  fmstnles  alone,  I  am 
disposed  to  consider  that  it  is  not  distinct  from  the  present ;  nor  does 
the  general  appearance  of  the  fronds  differ  so  much  as  to  be  irrecon- 
cilable with  this  impression.- 

Harvey's  Manual,  p.  210.  Wm.  Sm.,  B.  D.,  Vol  ii.,  p.  79,  PL  lix.^ 
fig.  370.  Bab.  Fl.  Eur.,  sect,  i.,  p.  273. — Schizonema  scoparium^ 
Kiitz.  Bac,  p.  114,  T.  xxvii.,  fig.  1. — Micromega  laciniatum,  Kalfs, 
in  Pritch.,  p.  932. 

Carrickfergns  to  Antrim,  collected  by  Dr.  David  Moore«  Galway^ 
collected  by  M*Calla. 

Schifjonema  gracillimumt  (Wm.  Sm.)    Marine. 

''  Frond  capillary,  simple  below ;  sparingly  branched  and  sub-mem- 
branous towai^  the  apices.  'Frustules  crowded  in  irregular  files. 
Valves  elliptico-lanceolate.  Length  of  frustule  .0009,  breadth  of  valve 
•00015." — Wm.  Smith.  StrieB  linear,  very  slightly  radiate.  Frustule  on 
front  view  narrow,  quadrangular.  So  far  as  the  frustules  are  concerned^ 
in  outline  and  gcnezal  appearance  the  species  differs  little  from  Schi- 
zonema parasiticum.  The  strise  may  be  a  little  coarser  and  the  valve 
somewhat  narrower. 

Wm.  Smith,  B.  D.,  Vol.  ii.,  p.  79,  PL  lix.,  fig.  372.— Micromega 
gracillimum,  Balfs,  in  Pzitch.,  p.  934. 

Nannywater,  Laytown,  Co.  Meath. 

(ttt)-  Frustules  without  stria. 

Schizonema  ohtusum,  (Grev.)     Marine. 

''  Frond  filiform,  sparingly  branched,  apices  abrupt.  Frustules 
exceedingly  numerous,  in  irregular  files ;  valves  elliptical.  Length  of 
frond  1";  length  of  frustule  0011;  breadth  of  valve  -00025."  Wm. 
Smith.  To  which  should  be  added  that  the  valves  are  rounded  at  the 
ends.     (PL  29,  fig.  20.) 

Greville,  Brit.  FL,  p.  413.  Harvey's  Manual,  p.  209.  Rab.  FL 
Eur.,  sect.  1,  p.  272. — ^Micromega  obtusum,  Balfs,  in  Pritch.,  p.  931. 

Near  Dunluce  Castle,  Portballintrae,  Co.  Antrim,  collected  by 
Dr.  David  Moore.    Merrion,  Malahide,  Co.  Dublin.     Galway. 

Sehiwonema  dilwynii,  (Agardh.)    Marine. 

"Frond  capillary  throughout,  sparingly  branched,  tenacious;  apices 
acute.  Frustules  exceedingly  crowded  towards  the  apices,  scattered  and 
remote  in  the  older  portions.  Valves  lanceolate,  acute.  Length  of  frond 
2"  to  5",  or  upwards ;  length  of  frustule  -0008  ;  breadth  of  valve  -0002." 
Wm.  Smith.  So  far  as  the  frustules  are  concerned  there  is  but  little 
difference  between  this  and  the  preceding  species ;  the  only  difference 


O'Meara— JB^or^  an  the  Irish  Diatomacm.  337 

being  that  while  in  the  former  case  the  ralye  is  rounded  at  the  ends,  in 
the  present  case  they  are  acute.  I  have  sometimes  found  both  species 
in  the  one  gathering. 

Agardh.  Syst.,  p.  10.  Id.  Consp.,  p.  20.  Grev.  Brit.  Fl.,  p.  412. 
Parvey's  Manual,  p.  212.  Kiitz.,  Bac,  p.  118,  T.  xxvi.,  fig.  3.  Wm. 
Sm.,  B.  D.,  Vol.  ii.,  p.  77,  PI.  Iviii.,  fig.  366.  Ealfs,  in  Pritch.,  p.  928. 
»ab.,  Fl.  Eur.,  sect.  1,  p.  272. 

Rathlin  Island,  Carrickfergus,  Camlough  Bay,  Co.  Antrim — all 
collected  by  Dr.  David  Moore.  Eiver  Nannywater,  Laytown,  Co.  Meath. 
Meirion,  Co.  Dublin. 

(b).  Achlamydm,    Frustules  toithout  a  gelatinous  investment. 

Genus  YI.  .  Diadesmis,  Kiitz. 
Frustules  united  in  a  filament. 


Diadeimia  tailltamsonii,  (Wm.  Sm.)    Marine. 

On  front  view  margins  of  frustules  undulate,  and  exhibiting  the 
striation  of  the  valve ;  on  side  view,  valve  linear,  acuminate  at  the 
ends.     Striae  moniliform.     (PL  29,  fig.  21.) 

This  form  was  first  partially  described  by  "Wm.  Smith,  B.  D.,  Vol. 
ii.,  p.  14,  PL  xxxiii.,  fig.  287,  who,  having  seen  only  the  front  view 
so  accurately  figured  by  him,  doubtfully  referred  it  to  the  genus 
Himantidium.  Subsequently  Gregory,  who  had  opportunity  of  more 
thoroughly  investigating  it,  transferred  it  to  the  genus  Diadesmis,  to 
which  it  properly  belongs.  Grunow  refers  this  species  to  the  genus 
Dimeregramma,  and  makes  the  following  observations : — **  Of  the 
Eunotia-like  structure  of  the  same  there  is  no  question ;  the  margins 
of  the  front  view  are  never  so  distinctly  triundulate  as  in  Smith's 
description ;  for  the  most  part  the  middlemost  elevation  is  found  much 
stronger  than  the  other  two,  in  consequence  of  which  it  approaches 
Dimeregramma  minor." — ^Verhand.  der  K.  K.,  ZooL  Bot.  GeseL,  Band 
xii.,  1862,  p.  377. 

Gregory,  Diat.  of  Clyde,  p.  25,  PL  x.,  fig.  40,  in  which  both  side 
and  front  views  are  accurately  delineated.  Ralfs,  in  Pritch,  p.  923. 
Bab.  n.  Eur.,  sect.  1,  p.  260. 

From  stomachs  of  Ascidians,  Eoundstone  Bay,  Co.  Galway. 

Genus  VII.    Bbebissonia,  Grunow. 
Frustules  simple,  stipitate. 


The  only  species  of  this  genus  was  by  Smith  described  and  figured 
under  the  name  of  Doryphora  Bocckii.    The  genus  Doryphora  had 


338  Proceedings  of  the^oyal  Irish  Academy. 

been  adopted  by  Kiitzing  for  tbe  reception  of  a  single  species  wbioL 
was  named  by  him  Dorypbora  ampbiceros.  His  definition  of  the  genus 
was,  **  frustules  simple,  depressed  on  the  secondary  side,  punctate, 
elliptico-lanceolate,  stipitate."  Bac.  p.  74.  Influenced,  no  doubt,  by 
the  consideration  of  the  last  named  characteristic,  Wm.  Smith  adopted 
the  genus  as  the  proper  place  for  another  form  named  by  him  Dory- 
pbora Boeckii,  and  to  some  extent  amended  the  definition :  **  Frustules 
stipitate,  lanceolate,  or  elliptical ;  valve  with  a  median  line ;  nodules 
obsolete." — ^B.  D.,  Vol.  i.,  p.  77.  This  definition  is  not  quite  correct 
as  respects  either  of  the  species  included  under  this  generic  designa- 
tion, for  Dorypbora  ampbiceros  has  no  median  line,  properly  so  called ; 
and  the  nodules,  though  small,  are  not  obsolete  in  the  case  of  Dory- 
pbora Boeckii.  The  latter  species,  Ralfs,  as  Ehrenberg  had  done  before, 
refers  to  the  genus  Cocconema,  but  properly  remarks,  "  This  species  is, 
no  doubt,  wrongly  referred  to  Cocconema,  since  both  margins  of  the 
lateral  valves  are  symmetrical.  "We  regard  it  as  a  stalked  Navicula ; 
and  find  a  central,  though  inconspicuous  nodule,  a  fact  which  forbids  it 
being  placed  in  Dorypbora,  as  Professor  Smith  proposed." — In  Pritch., 
p.  878.  Grunow  transfers  Dorypbora  ampbiceros  to  his  new  genus 
Rhapboneis,  and  recognising  the  intimate  relationship  of  Dorypbora 
Boeckii  to  Navicula,  suggested  the  adoption  of  a  new  generic  designa- 
tion, Brebissonia.  defining  it  simply  as  a  stipitate  Navicula. 

Heibcrg  recognises  the  proper  relationship  of  the  species,  as  Balfs 
and  Grunow  had  done,  but  rejecting  the  stipitate  character  as  of  no  con- 
sequence, described  the  form  as  Navicula  Boeckii. — De  Danske  Diat., 
p.  85.  At  all  events,  it  is  better  to  drop  the  genus  Dorypbora,  which  has 
been  so  ill  defined,  lest  confusion  should  arise  from  maintaining  it, 
even  though  with  a  more  precise  definition ;  and,  as  I  think  that  the 
stipitate  mode  of  growth  should  not  be  regarded  as  of  no  importance, 
I  adopt  the  suggestion  of  Grunow  above  referred  to. 

Brebissonia  boeckii,  Ehr.     Marine. 

Valve  on  side  view  lanceolate.  Striae  costate,  close,  radmte,  median 
line  obvious,  with  large  end  nodules,  and  ending  towards  the  central 
nodule,  in  pin-head-like  expansions ;  central  nodule  long  and  narrow, 
with  a  narrow  free  space  at  each  side  of  the  median  line.  (PI.  29, 
^g.  22.) 

Grunow,  Verhand.  der  K.  K.,  Zool.  Bot.  Gcsel.,  Band  x.,  1860, 
p.  512. — Cocconema  boeckii,  Ehr.  Infus.,  T.  xix.,  fig.  5.  Kiitz.  Bac., 
p.  81,  T.  vi.,  fig.  6.  Ralfs,  in  Pritch.,  p.  878,  PI.  vii.,  fig.  48.  Bab. 
Fl.  Eur.,  sect,  i.,  p.  83.— Dorypbora  boeckii,  Wm.  Sm.,  B.  D.,  Vol. 
i.,  p.  77,  PI.  xxiv.,  .fig.  223. — Navicula  boeckii,  Heiberg,  De  Danske 
Diat.,  p.  85. 

Stomachs  of  Ascidians,  Roundstone  Bay,  Co.  Gal  way.  Salt  ditch  on 
banks  of  Slaney,  near  Wexford.  River  Slaney,  Killurin,  Co.  Wex- 
ford. 


O'Meara — Report  on  the  Irish  DiatonMcece.  339 

Genus  VIII.     Navictjla,  Bory. 
Pmstriles  simple,  free. 


Ehrenberg  separated  the  forms  included  in  this  genus  into  two  dis- 
tinct genera,  Navicula  and  Pinnularia,  founded  on  the  fact  that  in  the 
former  the  strias  are  moniliform,  in  ihe  latter  costate.  Considerable 
difference  of  opinion  has  existed  as  to  whether  or  not  this  distinction 
is  tenable.  Kiitzing  rejected  it,  while  Wm.  Smith  and  Kabenhorst 
maintained  its  validity.  Kalfs,  in  Pritch.,  p.  892,  included  the  species  of 
Pinnularia  under  the  genus  Navicula  for  the  following  reasons: — 
'*  "Were  the  costce  always  plainly  developed,  as  in  Pinnularia  nbbilis  and 
its  allies,  no  difficulty  could  occur  in  determining  the  genera ;  but  in 
many  of  the  more  minute  species  it  is  often  very  difficult  to  distinguish 
between  striie  and  costae.  We  have  not  admitted  Pinnularia  here, 
partly  for  the  reason  just  given,  but  principally  because  we  cannot 
decide  to  which  genus  a  large  number  of  Ehrenberg' s  species  should 
be  referred."  The  existence  of  the  distinctive  characteristic  is  here 
admitted,  but  the  genus  founded  upon  it  is  discarded  on  account  of  the 
difficulty  of  applying  it  in  many  cases.  Grunow  regards  the  distinction 
between  costate  and  moniliform  striae,  in  this  case,  as  founded  on 
insufficient  observation.  He  says,  "  The  so-called  costae  in  the  Pinnu- 
lariae  are  quite  distinct  from  the  ribs  of  other  genera  of  Diatomaccae, 
and  consist  of  a  union  of  more  or  less  confluent  puncta,  which  cannot, 
indeed,  be  clearly  discriminated,  except  by  the  help  of  good  amplifica- 
tion and  well-managed  illumination." — Ueber  neue  oder  ungeniigend 
gekannte  Algen,  Verhandder  K.  K.  Zool.  Bot.  Gesel.,  Bandx.,  1860, 
p.  513.  This  eminent  author  thus  discards  the  distinction  between 
i^avicul%  and  Pinnularia,  and  is  followed  by  Heiberg,  Cleve,  and 
others.  Schumann,  who  adopts  the  same  view,  indicates  a  peculia- 
rity in  some  of  the  larger  forms  of  Pinnularia,  (P.  nobilis  and  P.  major, 
for  example,)  which  is  worthy  of  special  notice  here,  namely,  the 
interposition  of  very  fine  striae  between  the  costae,  which  he  says  are 
indistinct  in  P.  nobilis,  but  quite  distinct  in  P.  major ;  these  intersti- 
tial markings  I  have  never  been  able  to  discover,  and  Pfitzer  makes 
the  same  remark  concerning  them.  The  last-named  author,  in  his 
treatise  "  TJntersuchungen  ueber  Bau  und  Entwicklung  der  Bacillaria- 
ceen"  maintains  the  distinctiveness  of  the  genus  Pinnularia,  not  on  the 
ground  of  the  different  character  of  the  striation,  but  on  the  following 
peculiarities: — 1st.  The  so-called  costae  are  depressions  on  the  surface 
of  the  valve.  2nd.  The  valves  themselves  are  unsymmetrical.  3rd. 
The  arrangement  of  the  cell-contents  exhibits  a  marked  difference 
&om  those  of  Navicula,  as  well  in  the  normal  condition  as  also  in  the 
process  of  self-division. — Eegarding  the  characteristics  just  named, 
some  remarks  are  here  required.  As  to  the  first,  supposing  it  to  be 
true,  there  is  great  difficulty  in  applying  it  in  the  more  minute  forms. 


340  Proceedings  of  the  Royal  Irish  Academy, 

As  to  the  second,  Pfitzer  is  at  yariance  with  most  other  authors  who 
have  regarded  the  forms  included  under  the  genus  Pinnularia  as  pcr> 
fectly  symmetrical,  and  to  me  they  have  ever  appeared  just  as  symme- 
trical as  those  of  Navicula.  The  third  characteristic  is  that  which  ift 
most  worthy  of  notice,  hut  the  forms  in  which  the  peculiarity  has  heen 
ohserved  are  comparatively  few.  So  that  we  are  not  as  yet  in  a  posi- 
tion to  regard  it  as  satisfactorily  estahlished.  For  myself  I  have  long 
since  regcurdedthe  distinction  hctwecn  Navicula  and  Pinnularia  as  unsa- 
tisfactory, and  have  felt  ohliged  to  ahandon  it  in  consequence  of  having 
ohserved  forms  in  which  the  costate  character  of  the  Pinnulariae  i» 
combined  with  the  moniliform  striae  of  the  Naviculae.  In  consequence 
of  this  there  is  no  alternative  hut  the  abandonment  of  the  genus  Pin- 
nularia, or  the  adoption  of  a  new  genus  to  receive  these  forms  in 
which  the  characteristics  of  Navicula  and  Pinnularia  are  combined.  The 
former  appears  the  more  satisfactory  course,  which  I  have  accordingly 
pursued.  The  forms  belonging  to  this  genus  are  now  so  very  nume- 
rous some  more  satisfactory  grouping  of  them  than  that  of  Smith  and 
Balfs,  founded  on  the  outline  of  the  valves,  is  necessary.  Grunow 
has  done  much  towards  supplying  this  desideratum,  and,  if  I  have 
succeeded  in  effecting  an  improved  arrangement,  I  am  indebted  to  the 
hints  supplied  by  that  distinguished  naturalist. 

Conjugation  has  been  observed  in  some  species  of  Navicula.  Two 
mother  cells  produce  two  sporangial  cells  or  auxospores,  as  Pfitzer 
designates  them,  which  latter  are  found  to  lie  in  a  position  parallel  to 
that  of  the  former. 

(a.)  NohiUs. 

Stria  strongly  costate,  not  extending  to  the  median  line,  hut  leaving 
a  hroadj  smooth^  longitudinal  middle  space,  which  is  expanded  around  the 
central  nodule,  and  occasionally  extending  to  the  margin. 

Navictda  nohilis,  (Ehr.)     Presh  water. 

Valve  large,  varying  in  length  from  -012  to  -015 ;  oblong,  inflated 
both  at  the  middle  and  ends ;  costss  broad,  converging  in  the  middle, 
and  slightly  radiate  towards  the  ends;  longitudinal  free  median  spaco 
expanded  greatly  at  the  centre  and  ends.     (Plate  30,  flg.  1.) 

Kutz.  Bac,  p.  98,  T.  iv.,  fig.  24.  Ealfs,  in  Pritch.,  p.  895.  Gru- 
now, Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  615.  Cleve, 
Om  Svenska  och  Norska  Diat.,  p.  223. — Pinnularia  nobilis,  Ehr. 
Proc.  Beri.  Acad.,  1840.  Wm.  Sm.,  B.D.,  Vol.  i.,  p.  64,  PL  xvii.,  fig. 
161.  Rab.  SusBw.  Diat.,  p.  44,  T.  vi.,  fig,  2 ;  Rab.  PL  Eur.,  Alg.,  sect. 
1,  p.  209. 

Bantry,  Co.  Cork.  Featherbed  Mountain,  Co.  Dublin.  Lugna-^ 
quilla,  Co.  Wicklow.  Lough  Moume  deposit,  Co.  Antrim.  Dromore 
sub-peat  deposit,  Co.  Down.  River  Bann,  at  Coleraine,  Co.  Derry. 
Drumoughty  Lough,  near  Kenmare,  Co.  Kerry. 


O'Meara — Jteport  on  the  IrUh  Diatomacece.  341 

Niwicfda  mqfar,  (Eiitz.)    Fresh  water. 

Yalve  about  the  same  length  as  that  of  N.  nobilis;  oblong,  bnt  very 
slightly  expanded  in  the  middle,  and  at  the  rounded,  somewhat  conical, 
ends ;  longitudinal  free  space  narrower  than  that  of  N.  nobilis ;  cost» 
broad,  converging  in  the  middle,  and  nearly  parallel  for  the  remainder. 
On  front  view  frustule  linear  with  rounded  angles. 

Kiitz.  Bac,  p.  97,  T.  iv.,  fig.  19.  Balfs,  in  Pritch.,  p.  896.  Grunow, 
Verhand.  dcr  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  515.  Heiberg, 
De  Danske  Diat.,  p.  80.  Cleve,  Om  Svenska  och  Norska  Diat.,  p. 
223.— Pinnularia  major,  W.  8m.,  B.D.,Vol.  i.,  p.  54,P1.  xviii.,  fig.  161. 
Eab.  Sussw.  Diat.,  p.  42,  T.  vi.,  &£.  5.  Do.  Fl.  Eur.  Alg.,  sect.  1, 
p.  210. 

Lower  Lake,  Killarney,  River  near  Glenc&r,  Co.  Kerry.  River 
Bann,  near  Coleraine,  Co.  Deny.  Marl  pit,  near  Arklow,  Streamlets 
on  Carrickmacreilly  Hill,  Greenane,  Co.  Wicklow.  Derrylane  Lough, 
Co.  Cavan.  Kallakee,  Featherbed  Mountain,  Co.  Dublin.  Slievo 
Donard,  Co.  Down.  Lough  Moume  deposit.  Dromore  Sub-peat 
deposit.  Lough  Islandreavy  deposit.  Pond  near  Camolin,  Co.  Wex- 
ford. 

Navicula  cardinaliSf  (Ehr.)     Fresh  water. 

Valve  oblong-linear,  length  about  -0125;  breadth  about  '0022, 
rounded  at  the  ends ;  median  line  undulate ;  end  nodules  large ;  free 
intermediate  space  wide,  reaching  the  margin  in  the  middle,  forming  a 
broad  stauroform  space;  costss  broad,  converging  in  the  middle,  nearly 
parallel  for  the  remainder.     (PI.  30,  fig.  2.) 

Ralfs,  in  Pritch.,p.806,Pl.xii.,  fig.  72.  Grunow,  Verhand.  derK.K. 
Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  515. — Pinnularia  cardinaUs,  Ehr. 
Wm.  Sm.,  B.D.,  Vol.  i.,  p.  65,  PI.  xix.,  fig.  166.  Rab.  Fl.  Eur.  Alg., 
sect  1,  p.  220. — Stauroneis  cardinalis,  Kiitz.  Bac,  p.  106,  T.  xxix., 
fig.  10. 

Lough  Moume  deposit ;  found  also  living  in  a  pond  near  the  city 
of  Armagh. 

Navietda  vtrtdti,  (Nitzsch.)    Fresh  water. 

Valve  varying  much  in  size ;  linear  elliptical,  with  rounded  ends ; 
intermediate  free  space  narrower  than  in  the  three  preceding  species, 
and  not  so  much  expanded  in  the  middle;  cost®  broad,  but  not  so  much 
80  as  in  the  preceding.     (PI.  30,  fig.  3.) 

This  species  has  been  attributed  to  various  authors,  but  if  Kiitzing 
be  right  in  supposing  it  to  be  =  Bacillaria  viridis,  Nitzsch,  1817,  it 
should  be  attributed  to  the  last  named  author,  as  Heiberg  has  done. 
Smith  assigns  the  species  to  himself,  although  regarding  it  as  =  Navi- 
cula viridis,  Ehr.  Rabenhorst  attributes  it  to  himself,  while  Grunow 
attributes  it  to  Kiitzing.  Grunow  makes  this  form  the  type  of  the 
group  Virides,  but  seems  to  regard  Navicula  major,  which  he  includes 


342  Proceedings  of  the  Royal  Irish  Academy. 

among  the  Nobiles,  to  be  only  a  variety  of  Navicnla  viridiB.  Speaking 
of  this  former,  he  says,  **  it  appears  to  me  to  be  only  a  variety  of  Nav. 
viridis,  tolerably  numerous  figures  (especially  from  specimens  out  of 
the  Kieselguss  of  Pranzcnsbad),  which  lie  before  me,  present  such 
manifold  transitions,  as  well  in  respect  to  the  appearance  of  the  stria- 
tion  as  to  the  outline  of  the  form,  that  in  most  cases  it  is  difficult  to 
decide  whether  the  specimen  should  be  referred  to  one  or  the  other." 
Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  515. 

The  correctness  of  this  remark  is  obvious  to  all  careful  observers, 
but  still  the  species  seem  to  be  distinct.  The  following  characters 
seem  to  distinguish  Navicula  viridis  from  K.  major;  the  cost®  arc 
finer  and  less  radiate ;  the  median  free  space  is  narrower  and  less  ex- 
panded around  the  central  nodule,  and  the  normal  outline  is  linear 
elliptical. 

Kutz.  Bac,  p.  97,  T.  iv.,  ^g,  18.  Balfs,  in  Pritch.,  p.  907,  PL  ix., 
figs.  135,  136.  Grrunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band 
X.,  1860,  p.  518.  Heiberg,  De  Danske  Diat.,  p.  80.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  223. — Pinnularia  viridis,  Wm.  Sm., 
B.D.,  Vol.  i.,  p.  54,  PL  xviii.,  fig.  163.  Rab.  Sussw.  Diat.,  p.  42,  T. 
\i.,  fig.  4. 

Featherbed  Mountain,  Friarstown,  Co.  Dublin.  River  Erne,  near 
Grossdoney,  Derrylane  Lough,  Co.  Cavan.  Ditch  near  Cushendun, 
Co.  Antrim,  Drumoughty  Lough,  near  Kenmare,  Lower  Lake,  Kil- 
lamey.  Eiver  near  Glencar,  Co.  Kerry.  Greenane  Carrickmacreilly 
Hill,  Lugnaquilla,  Co.  Wicklow.  Lough  Corrib,  Co.  Galway.  Lough 
Moume  deposit,  Sub-peat  deposit,  Dromore,  Co.  Down. 

Navicula  alpina,  (Wm.  Sm.)     Fresh  water. 

Length  of  valves  about  -0060,  breadth  about  -0018 ;  broadly  ellip- 
tical, with  rounded  ends ;  intermediate  free  space  wide,  but  slightly 
expanded  around  the  central  nodule ;  costo3  broad,  convergent  in  the 
middle,  and  radiate  towards  the  ends.     (PI.  30,  fig.  4.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  p. 
522. — Pinnularia  alpina,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  55,  PL  xviii.,  fig. 
168.     Rab.  FL  Eur.  Alg.,  sect.  1,  p.  213. 

On  the  slopes  of  Slieve  Donard,  Co.  Down.  Killakee,  Featherbed 
Ifountain,  Co.  Dublin. 

JNarieula paohyptera,  (Ehr.)    Freshwater. 

Frustules  regidarly  quadrangular  on  front  view ;  length  of  valve 
about  -0034,  breadth  about  -0013;  slightly  inflated  in  the  middle, 
rounded  at  the  ends ;  intermediate  free  space  but  slightly  expanded  in 
the  middle;  costsB  broad,  slightly  converging  in  the  middle,  and  nearly 
parallel  for  the  remainder.     (Plate  30,  fig.  5.) 

Kiitz.  Bac.,  p.  98,  T.  xxviii..  fig.  58.  Ralfs,  in  Pritch.,  p.  896, 
who  considers  the  species  distinct  from  Pinnularia  lata,  Wm.  Smith, 


O'Meaba — Report  on  the  Irish  Diatomacece,  343 

which  latter  he  refers  to  as  Navictila  lata,  p.  908.  Gmnow,  Yerhoad. 
der  K.  K.  Zool.  Bot.  Gesel.,  Band  x.,  1860,  p.  615.— Pinnularia 
pachjptera»  Rah.  Siissw.  Diat.,  p.  44,  T.  vi.,  fig.  11. — Pinniilaria 
lata,  Wm.  Sm.,  B.D.,  Vol.  i.,  p.  55,  PI.  xviii.,  fig.  167.  Kiitzing 
describes  a  form  as  Navicnla  lata,  Bac,  p.  92,  T.  iii.,  fig.  51,  which  is 
obviously  different  from  the  present. 

Pool,  Glencree,  Co.  "Wicklow.  River  Dodder,  Featherbed  Moun- 
tain, Co.  Dublin.    River  Bann,  near  Hilltown,  Co.  Down. 

Navicula  distans,  (Wm.  Sm.)    Marine. 

Frustule  on  front  view  slightly  constricted  in  the  middle,  and 
gently  attenuated  at  the  ends ;  valve  lanceolate,  length  about  *0045, 
breadth  about  *0010 ;  costa)  not  so  robust  as  in  the  preceding ;  conver- 
gent; intermediate  free  space  lanceolate,  much  expanded  in  the 
middle  and  narrow  towards  the  ends.     (Plate  30,  fig.  6.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesel.,  Bandx.,  1860,'p.  523. 
Ralfs,  in  Pritchi.,  p.  907.  Cleve,  Om  Svenska  och  NorskaDiat.,  p.  224. 
— ^Pinnularia  distans,  "Wm.  Sm.,  B.  D.,  Vol.  i.  p.  56,  PI.  xviii.,  fig.  169. 
Rab.  Fl.  Eur.  Alg.,  sect.  1,  p.  214. 

Sea-weeds,  Bannow,  Co.  Wexford.  Sea-weeds,  Malahide,  Sto- 
machs of  Pectens,  Dalkey,  Piles  of  wooden  bridge,  Dollymount 
Strand,  Sea- weeds,,  Howth,  Co.  Dublin.  Stomachs  of  Ascidians, 
Belfast  Lough,  Co.  Antrim.  Stomachs  of  Ascidians,  Co.  Clare.  Sea- 
weeds, Kilkec,  Co.  Clare. 

Navicula  undulata,  N.  S.     Marine. 

Length  of  valve  *0060,  breadth,  '0015 ;  lanceolate  with  rounded 
ends;  median  line  undulate,  intermediate  free  space  lanceolate,  greatly 
expanded  in  the  middle;  costss  strong,  convergent.     (PI.  30,  fig.  7.) 

Sea-weeds,  Giants'  Causway,  Co.  Antrim. 

Navicula  rectangulata^  (Gregory.)     Marine. 

Valve  linear;  length  about  '0040,  breadth  about  '0010;  slightly 
expanded  at  the  middle  and  ends,  which  latter  are  rounded;  inter- 
mediate free  space  narrow  at  ends,  but  roundly  expanded  in  the 
middle ;  costse  strong,  converging  in  the  middle,  and  radiate  towards 
the  ends ;  frustule  on  front  view  constricted  in  the  middle.  (Plate 
30,  fig.  8.) 

Gregory,  Diat.  of  Clyde,  p.  479,  PI.  ix.,  fig.  7.  Donkin,  N.  H. 
Brit.  Diat.,  p.  66,  PI.  x.,  fig.  5. — Pinnularia  rectangulata,  Rab.  Fl. 
Eur.  Alg.,  sect.  1,  p.  215. 

Stomachs  of  Ascidians,  Broadhaven,  Co.  Galway. 


344  Proceedings  of  the  Royal  Irish  Academy. 

Navieula  trevelyana,  (Donkin.)    Marine. 

Frogtule  on  front  view  deeply  constricted,  with  truncate  extremi- 
ties; middle  and  end  nodules  apparent,  with  a  narrow  sli^tly  lunate 
unstriate  band  at  either  side  of  the  central  nodule ;  Talve  linear,  rounded 
at  ends ;  length  about  '0048,  breadth  about  *0008 ;  median  line  some- 
what undulate;  intermediate  free  space  narrow,  except  around  the 
median  nodule,  where  it  is  much  and  roundly  expanded;  costse  strong, 
conyerging  in  the  middle,  and  radiate  towards  the  ends.  (Plate  30, 
H'  9.) 

Donkin,  Q.  J.  M.  S.,  1861,  p.  viii.,  PI.  1,  fig.  2.  Do.  N.  H.  Brit. 
Diat.,  p.  66,  PI.  10,  fig.  6. — ^Pinnularia  trevelyana,  Bab.  El.  Eur.  Alg. 
sect,  i.,  p.  210. 

Bannow,  Co.  Wexford.    Malahide,  Co.  Dublin. 

Navicula  ohbrnga,  (Kiitz.)     Fresh  water. 

Frustales  on  front  view  quadrangular,  narrow;  valve  narrow, 
elliptical ;  length  about  *0058,  breadth  about  '0007 ;  apices  broad, 
rounded ;  costse  strong,  convergent ;  intermediate  free  space  narrow, 
except  in  middle,  where  it  is  roundly  expanded.    (PI.  30,  ^g,  10.) 

Kutz.  Bac,  p.  97,  T.  iv.,  ^g.  21.  Balfs,  inPritch.,  p.  907.  Gru- 
now,  Verhand.  der  K.  K.,  Zool.  Bot.  Gcscl,  Band  x.,  1860,  p.  523. 
Cleve,  Om  Svenska  och  Norska  Diat.,  p.  225. — Pinnularia  oblonga, 
Wm.  8m.  B.  D.,  Vol.  i.,  p.  54,  PI.  xviii.,  fig.  165.  The  form  described 
by  Rabenhorst,  Siissw.  Diat.,  p.  45,  T.  vi.,  fig.  6,  as  Pinnularia 
oblonga,  is  obviously  different  from  the  present  species. 

Castlebridge,  Co.  Wexford.  River  near  Glencar,  Co.  Kerry. 
Pond,  Newcastle-Lyons,  Co.  Dublin.  Powerscourt  Demesne,  Eilcool, 
Co.  Wicklow. 

Na/vicula  oblonga^  var,  lanceolataf  (Grunow.)     Fresh  water. 

Valve  shorter  and  broader  than  in  the  typical  form,  lanceolate, 
with  rounded  ends ;  intermediate  free  space  narrow. 

Grunow  remarks  that  this  variety  **  stands  near  to  Pinnularia  pere- 
grina,  as  described  by  Wm.  Smith,"  but  it  is  certainly  distinct,  being 
found  in  localities  beyond  the  reach  of  marine  infiuence.  It  may 
be  distinguished  from  Navicula  percgrina  by  the  intermediate  free 
space,  expanded  in  the  middle,  which  that  form  does  not  exhibit. 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gcscl.,  Band  x.,  1866,  p. 
523,  T.  iv.,  ^g.  25. 

Lough  Mouine  deposit,  Co.  Antrim. 

Navicula  langa,  (Gregory.)    Marine. 

Valves  lanceolate;  length  about  -0060;  breadth  about  '0010; 
costffi  strong,  distant,  slightly  radiate  in  Ihe  middle,  more  radiate 


O'Meara — Repm't  on  the  Irish  Diatomacew.  345 

towards  the  ends ;  intermediate  free  space  narrow,  except  in  the  cen- 
tre, where  it  is  somewhat  rhombically  expanded.  (PI.  30,  fig.  11.) 
Ralfs,  in  Pritch.,  p.  906.  Donkin,  K.  H.  Brit.  Diat.,  p.  65,  PL 
viii.,  fig.  3. — Pinnularia  longa,  Gregory,  Q.  J.  M.  S.,  Vol.  iv.,  1856, 
p.  47,  PL  5,  fig.  18.     Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  218. 

Arran  Islands;  Stomachs  of  Ascidians,  Bonndstone  Bay,  Co. 
Oalway. 

Nametda  divergenSf  (Wm.  Sm.)     Fresh  water. 

Valve  oblong ;  length  from  about  '0035  to  '0055,  breadth,  from 
about  -0007  to  -0012.  Gibbous  in  the  middle,  attenuated  towards  the 
alightly  constricted  and  rounded  extremities.  Costae  strong,  con- 
Tergent  in  the  middle,  and  radiate  towards  the  ends.  Intermediate 
free  space  narrowed  towards  the  ends,  where  there  is  a  slight  expan- 
«ion ;  greatly  expanded  in  the  middle,  reaching  the  margin  in  a  tole- 
rably broad  stauroform  band. 

Ralfs,  in  Pritch.,  p.  896.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot. 
OeseL,  Band  x.,  1860,  p.  523.  Cleve,  Om  Svenska  och  Korska 
Diat.,  p.  225. — Pinnularia  divergens,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  57 ; 
PL  xviii.,  fig.  177.     Rab.  Fl.  Eur.  Alg,  sect,  i.,  p.  221. 

Drumoughty  Lough,  near  Xenmare,  County  Kerry.  Featherbed 
Mountain,  Killakee,  County  Dublin.  Bantry,  County  Cork.  Lake 
near  Castlewellan,  County  Down.  Lough  Moume  deposit,  County 
Antrim. 

Ndvtcula  divergens,  var.  longa,  (O'Meara.)     Fresh  water. 

Valve  oblong,  linear.  Length  about  -0059  ;  breadth  about  -0008; 
Tery  slightly  expanded  in  the  middle  and  at  the  rounded  ends.  Costse 
as  in  the  typical  form ;  intermediate  free  space  as  in  typical  form,  but 
scarcely  reaching  the  margin,  compared  with  which  it  is  relatively 
narrower  in  middle,  and  broader  at  the  ends.     (PL  30,  fig.  13.) 

Pond  near  the^City  of  Armagh. 

Navictda  divergens,  var,  elliptica,  (O'Meara.)    Fresh  water. 
Like  the  typical  species  but  broadly  elliptical. 

Lough  Moume  deposit,  Co.  Antrim. 

Navicula  horealis,  (Ehr.)     Fresh  water. 

Valve  narrow,  elliptical,  with  rounded  ends.  Length  about  '0015 ; 
breadth  about  -0004.  Costae  short,  parallel ;  intermediate  free  space 
relatively  wide,  elliptical.     (PL  30,  fig.  14.) 

Kiitz.  Bac.  p.  96.  T.  xxviii.,  figs.  68  72,  (where  it  is  identified  with 
Pinnularia  borealis,  Ehr.)  Grunow,  Verhand.  der  K.  K.  Zool.  Bot. 
OeseL,  Band  x.,   1860,  p.  518. — ^Knnularia  borealis,    Rab.   Siissw. 


346  Proceedings  of  t/ie  Royal  Irish  Academy. 

Diat.,  p.  42,  T.  vi.,  fig.  1 9.  Do.  Fl.  Eur.  Alg.,  sect.  1 ,  p.  2 1 6  (where  it  i» 
identified  with  Pinnularia  latestriata.)  Gregory  Q.  J.  M.  8.,  Vol.  ii.^ 
1854,  PL  iv.,  fig.  13.     Wm.  Sm.,  B.D.,  Vol.  ii.,  p.  94. 

Drumoughty  Lough,  near  Kenmare,  Co.  Kerry.  Pond  near  Glen- 
chree,  Co.  Wicklow.  Ulster  Canal,  near  Poyntzpass,  Co.  Armagh. 
Loughhrickland,  Co.  Down.  Ciishenden,  Lough  Neagh,  Co.  Antrim,. 
Featherbed  Mountain,  Co.  Dublin. 

Navicula  menapiensist  N.  S.     Marine. 

Valve  small;  length  -0016;  breadth  '0005;  linear,  ends  rounded 
and  slightly  conical.  Costas  marginal,  distant;  intermediate  free 
space  tolerably  wide,  linear  elliptical.     (PL  30,  fig.  15.) 

This  form  is,  in  some  respects,  similar  to  the  last,  but  strisB  are 
longer;  otherwise  distinguished  by  its  marine  habitat. 

Sea- weeds,  Bannow,  Co.  Wexfonl.  Stomachs  of  Ascidians,  Broad- 
haven  Bay,  Co.  Galway. 

Navicula  tabellaria^  (Ehr.)     Fresh  water. 

Valve  oblong,  slightly  expanded  at  the  middle  and  ends.  Length 
about  "0050 ;  breadth  about  '0007.  CostaB  strong,  convergent  in  the 
middle,  then  parallel  and  radiate  towards  the  ends ;  intermediate  free 
space  wide,  roundly  expanded  in  the  middle.     (Plate  30,  fig.  12.) 

Kiitz.  Bac,  p.  98,  T.  xxviii.,  figs.  79,  80,  where  the  costaj  are 
described  incorrectly  as  reaching  the  median  line ;  also  T.  xxx.,  fig. 
20,  where  the  costa)  are  represented  as  marginal,  whereas  they  extend 
much  further  towards  the  median  line.  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  GeseL,  Band  x.,  1860,  p.  516.  Ralfs,  in  Pritch.,  p.  896, 
PL  xii.,  fig.  21.  Cleve,  Cm  Svenska  och  Norska  Diat.,  p.  224. 
Donkin.,  N.  H.  Brit.  Diat.,  p.  70,  PL  xii.,  fig.  4.— Pinnularia 
tabellaria,  Ehr.  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  58,  PL  xix.,  fig.  181. 
llab.  Siissw.  Diat.,  p.  44,  T.  vi.,  fig.  24.  Do.  FL  Eur.  Alg.,  sect,  i.^ 
p.'Sll. 

Friarstown,  Piperstown,  Featherbed  Mountain,  Killakee,  Co^ 
Dublin.  Glenchree,  Lugnaquilla  Mountain.  Co.  Wicklow.  Glencar^ 
Co.  Kerry.  Lough  Corrib,  Co.  Galway.  Lough  Moume  deposit,  Co^ 
Antrim. 

Navicula  tabellaria^  var,  acrosphariaf  (De  Br^b.)     Fresh  water. 

Like  the  typical  form.     The  costse,  however,  are  marginal. 

Navicula  acrosphaeria,  Kiitz.  Bac,  p.  97,  T.  v.,  fig.  11,  where 
it  is  alleged  that  the  form  is  identical  with  Frustulia  acrosphaeria^ 
De  Br^bisson,  to  whom,  on  this  account,  I  attribute  the  species. 
Half 8,  in  Pritch.,  p.  896. — Navicula  tabellaria,  Grunow,  who  observes, 
that  "  Wm.  Smith's  figures  and  descriptions  of  Navicula  acrosphaeria 
and  N.  tabellaria  difPer  only  in  the  different  size  and  the  somewhat 


i;«<^-  \etve-^.«8Ja»  ,,a\er  ^e  toi***^ 


gently  fS^eTif^o^,f^O>S-^^  J     ^t^ta- 


946  Proceedings  of  the  Eoyai  Irish  Academy. 

NavicuJa  gibha^  (Ehr.)  Fresh  water. 
.  Yalve  nearly  linear;  very  slightly  constricted  towards  the  ends, 
and  very  gently  expanded  in  the  middle.  Length  about  '0044; 
breadth  about  '0008.  Strise  finely  coetate ;  convergent  in  the  middle, 
and  radiate  towards  the  ends.  Intermediate  free  space  narrow,  except 
in  the  middle,  where  it  is  roundly  expanded.     (Fl.  30,  fig.  19.) 

Kiitzing,  (Bac.,  p.  98,  T.  xxviii.  fig.  70),  has  described  a  form  under 
thifl  name,  which  he  regards  as  Pinnulazia  gibba,  Ehr.  With  this  the 
form  so  named  by  Rabenhorst  (Siissw.  Diat.,  p.  45,  T.  vi.,  fig.  27),  agrees. 
Rslfs'  description  seems  tolerably  well  to  correspond,  ''lanceolate, 
with  dilated  capitate  ends."  In  the  above  cases  the  figures  represent 
the  form  more  gibbous  in  the  middle  than  the  present  species,  and 
with  capitate  ends ;  the  strisd  also  are  parallel,  while  in  the  present 
form  they  are  convergent  in  the  middle,  and  radiate  at  the  ends,  just 
as  Wm.  Bmith  has  figured  Pinnuloiia  gibba,  B.  D.  Vol.  i.,  p.  58,  PL 
xix.,  fig.  180.  The  present  form  is  less  capitate  at  the  ends,  and  the 
intermediate  free  space  more  roundly  expanded  in  the  middle  than  in 
Smith's  figure.  Orunow,  comparing  the  species  he  has  named  l^avi- 
cula  gibba  with  Navicula  tabellaria,  says  it  stands  distinct  horn  if  by 
the  narrower  expansion  of  the  ends,  and  the  more  gradual  tapering  in 
the  middle."  Verhand.  der  K.  K.  ZooL  Bot.  Oesell.,  Band  x.,  1860, 
p.  517.     This  description  corresponds  exactly  with  the  present  form. 

Lough  Corrib,  Co.  Galway.  Drumoughty  Lough,  near  Kenmare^ 
Co.  CoriL  Cam  Lough,  near  Tralee,  Co.  Kerry.  Derrylane  Lou^, 
Co.  Cavan.  Carrickmacreely  Hill,  Lugnaquilla  Mountain,  Bathdrum, 
Co.  Wicklow.  Featherbed  Mountain,  Co.  Dublin.  Lough  Moume 
deposit,  Co.  Antrim. 

Navicula  gihhaf  var,  hoeckii,  (Bab.)    Presh  water. 

Yolve  smaller  than  the  tj^ical  species;  length  '0032,  breadth 
'0007 ;  margin  very  slightly  gibbous ;  ends  somewhat  capitate ;  striae 
finely  costatc ;  intermediate  free  space  narrow,  except  at  the  middle, 
where  it  expands  considerably,  sometimes  reaching  the  margin  at  one 
side,  but  not  at  the  other.     (Plate  30,  fig.  20.) 

Grunow,  Verhand.  derX.  K.  Zool.  Bot.  Oesell.,  Band  x.,  1860, 
p.  517,  T.  iv.,  fig.  17.  This  author  regards  the  form  as  identical  with 
Staurophora  peckii,  Bab.  Bacil.  Sachs. 

Lough  Corrib,  Co.  Galway.    Pond  near  the  city  of  Armagh. 

Navicula  gihha,  var.  porta,  (O'Meara).     Fresh  water. 

Valve  small ;  length  -0015,  breadth  '0003 ;  slightly  gibbous  at  the 
margins;  much  attenuated  towards  the  somewhat-capitate  ends;  stri» 
costate,  fine,  convergent  in  the  middle,  andslightlyradiate  towards  the 
ends;  intermediate  free  space  relatively  broad,  expanding  at  the 
middle,  and  sometimes  reaching  to  the  margin.     (Plate  30,  fig.  21.) 

There  is  a  form  somewhat  similar  to  this  described  by  Grunow 


O'Meara — Report  on  the  Irish  Diatomacea.  349 

xmder  the  name  of  Nayicnla  stanroptera,  var.  parva,  Yexliaad*  der 
Z.  K.  ZooL  Bot.  Geeell.,  Band  x.,  1860,  p.  517,  T.  iv.,  fig.  19.  The 
striation  in  the  present  form  is,  however,  coarser  than  in  Qmnow's 
figure,  the  latter  also  being  more  robust,  for  which  reasons  I  hesitate 
to  identify  the  {nresent  form  with  that  of  Grunow. 

Longh  ]N'ea^,  near  Lurgan,  Go.  Armagh.  Gamolin,  Co.  Wez^ 
ford. 

Nimeula  hemtptera,  (Kiitz).     Fresh  water. 

Valve  linear,  elliptical,  with  rounded  ends ;  length  *0025,  breadth 
-0005 ;  striae  costate  linear,  convergent  at  the  ziiiddle,  and  radiate  to- 
wards the  ends ;  intermediate  free  space  narrow,  somewhat  expanded 
in  the  middle.     (Plate  30,  fig.  22.) 

Kutz.  Bac.,  p.  97,  T.  xxx.,  fig.  11.  Ealfs,  in  Pritch.,  p.  908; 
Grunow,  Yerhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  519. 
This  author  considers  the  form  may  be  only  a  variety  of  Navicula . 
viridis,  which  it  greatly  resembles,  except  that  it  is  smaller,  and  the 
stiiation  very  much  finer.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  223. — ^Pinnularia  hemiptera,  "Wm-'Sm.,  B.D.,  Vol.  ii.,  p.  95.  Eab. 
Siissw.  Diat.,  p.  42,  T.  vi.,  fig.  17.  Do.  Fl.  Eur.  Alg.,  sect.  i. 
p.  212. 

Lucan,  Featherbed  Mountain,  Friarstown,  Co.  Dublin.  Siver 
£me,  near  Crossdoney,  Derrylane  Lough,  Co.  Cavan.  Lough  Erne, 
Co.  Fermanagh.  Lough  Neagh,  near  Lurgan.  Ulster  Canal,  near 
Poyntzpass,  Co.  Armagh.  Pool  near  Glengamff,  Co.  Cork.  Stareamlet, 
Cushendun,  Co.  Antnm.  River  Bann,  near  Coleraine,  Co.  Deiry- 
Sub-peat  deposit,  Dwmore,  Co.  Down. 

Navieula  apieulata,  (De  Breb.)    Marine. 

Valve  linear  in  the  middle,  gradually  tapering  towards  the  ends, 
which  run  out  into  acute  short  beaks ;  length  *0026,  breadth  -0008 ; 
cost®  fine,  converging  in  the  middle,  radiate  towards  the  ends ;  inter- 
mediate free  space  narrower  towards  the  ends,  expanded  in  the  middle. 
(PI.  30,  fig.  23.) 

Pinnularia  rostellata,  Gregory,  Diat.  of  Clyde,  p.  488,  PI.  ix.,  fig. 
20,  1857. — ^Navicula  apiculata,  De  Br^bisson  Diat.  da  Littoral  de 
Cherbourg,  p.  16,  P1.L,  fig.  5,  1867.  Balfs,  in  Pritch.,  p.  908.  Donkin 
'N.  H.  Brit.  Diat.,  p.  56,  PL  viii.,  fig.  6.  Kiitzing  has  described 
a  form  as  Kavicula  rostellata,  which  is  quite  distinct  from  the  present ; 
it  is  therefore  necessary  to  drop  the  specific  name  adopted  by  Gregory, 
and  substitute  for  it  De  Br^bisson's  name,  Navicula  apiculata. 

Gregory  and  De  Br^bisson  describe  the  striae  as  reaching  the 
median  line ;  Donkin  more  correctly  represents  them  as  falling  short 
of  it,  but  does  not  describe  the  central  expansion  of  the  free  inter- 
mediate space. 

2B2 


350  Proceedings  of  the  Bayal  Irish  Academy. 

Naioimda  hrhhissonii,  (Kiitz).     Fresh  water. 

Yalye  linear,  elliptical;  ends  somewhat  rounded;  length  '0016, 
breadth  -0005 ;  costflB  iine,  radiate ;  intermediate  free  space  narrow, 
except  in  the  middle,  where  it  expands,  reaching  the  margin  in  a 
stauroform  band  widening  towards  the  margin.     (Plate  30,  fig.  24.) 

Kuta.  Bac.,  p.  93,  T.  iu.,  fig.  49.  Ealfs,  in  Pritch.,  p.  897. 
Oronow,  Yerhand.  der  K.  K.  Zool.  Bot.  Oesell.,  Band  x.,  1860,  p.  519. 
— ^Pinnnlaiia  Btanroneifomus,  Wm.  Sm.,  B.D.,  Vol.  i.,p.  57,  PI.  xix., 
fig.  178.    Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  222. 

Drumoughty  Lough,  near  Kenmaro,  Bantry,  Co.  Cork.  Denr- 
lane  Lough,  Co.  Cavan.  Bathdrum,  Featherbed  Mountain,  Co.  Wick- 
low.    KUlakee,  Co.  Dublin.    Lough  Gill,  Co.  Kerry. 

Na/cieuia  hrihissontif  var,  angtuta^  (Grun.)    Fresh  water. 

Valve  narrow,  elliptical;  ends  attenuated,  and  slightly  rounded; 
length  '0016,  breadth  '00025;  costsa  fine,  radiate;  intermediate  free 
space  narrow,  except  in  the  middle,  where  it  expands,  reaching  the 
margin  in  a  stauroform  band  narrower  than  in  the  typical  species. 
(Plate  30,  fig.  25.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  519,  T.  T.,  fig.  18. 

Derrylane  Lough,  Co.  Caran.     Camolin,  Co.  Wexford. 

Navicula  icostawron,  (Ehr.)    Fresh  water. 

Valve  linear,  elliptical ;  length  '0028,  breadth  '0006 ;  cost©  fine, 
radiate ;  intermediate  free  space  narrow,  except  in  the  middle,  where 
it  expands  into  a  narrow  stauroform  parallel  band  reaching  the  margin. 
(Plate  30,  fig.  27.) 

Stauroptera  icostauron,  Ehr.,  as  Grunow  suggests,  Verhand.  der 
K.  K.  Zool.  Bot.  Gesell.,  Bondx.,  1860,  p.  519. — Stauroneis  icostauron, 
Kiitz.  Bac.,  p.  106,  T.  xxix.,  fig.  10. — Pinnulariaviridis,  var.  B.,  "Wm. 
Sm.,  B.D.,  Vol.  L,  p.  54,  PI.  xviii.,  fig.  163  B. 

Derrylane  Lough,  Co.  Cavan.  Adiigoole,  Co.  Kerry.  Featherbed 
Mountain,  Co.  Dublin.     Lake  near  CastleweUan,  Co.  Down. 

NamcuJa  stauroptera^  (Grunow).     Fresh  water. 

Valve  linear,  elliptical,  with  rounded  ends ;  length  '0025,  breadth 
'0007 ;  costsB  coarse,  convergent  in  the  middle,  radiate  towards  the 
ends ;  intermediate  free  space  narrow,  except  in  the  middle,  where  it  is 
much  expanded,  appearing  sometimes  to  reach  the  margin,  but  really 
not  so.     (Plate  30,  fig.  28.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Bandx.,  1860,  p. 
516.  Stauroptera  parva,  Ehr.,  according  to  Kiitzing. — Stauroneis 
porva,  Kiitz.  Bac.,  p.  106,  T.  xxix.,  fig.  23.  Gregory  has  described  a 
form  as  Pinnularia  parva,  Q.  J.  M.  S.,  1854,  p.  98,  PI.  iv.,  fig.  11.    To 


O'Mbaba — Bepart  on  the  Iriah  DiatomacecB.  351 

aToid  confusion,  the  specific  name  adopted  by  Ehrenberg  and  Kiitzing 
for  this  species  had  best  be  abandoned,  and  the  designation  proposed 
by  Gnmow  as  abore  substitated  for  it. 

Baphoe,  Co.  Donegal.  Lough  I^eagh,  near  Lnrgan,  Co.  Armagh. 
Sab-peat  deposit,  Dromore,  Co.  Down. 

Naviada  haeiUum,  (Ehr.)    Fresh  water. 
^  Yalyes  linear ;  ends  rounded;  costsd  fine,  strongly  marked  in  the 
middle,  radiate;  inteimediate  free  space  narrow,  slightly  expanded  in 
the  middle;  length  about  *0018,  broadth  about  *0005.    (Plate  SO, 
fig.  29.) 

Ehrenberg  has  given  many  figures  of  a  species  so  named,  some  of 
which  aro  utterly  undistingnishable ;  one  from  a  marine  habitat  in- 
dicated cannot  be  the  same.  Two,  however,  of  his  figures  aro  plain 
enough  for  satisfactory  identification. 

Ehr.  Mic.  T.  xv.,  A.  fig.  38 ;  T.  ii.,  2.  fig.  14.  Kutz.  Bac.,  p.  96, 
T.  xxviii.,  fig.  69.  Wm.  Sm.,  B.D.,  Vol.  ii.,  p.  91.  Balfo,  in  Fritch., 
p.*  907.  Grunow,  Yerhand.  der  K.  K.  Zool.  Bot.  Gk)sell.,  Band  x.» 
1860,  p.  551,  T.  iv.,  fig.  1.  Eab.  Sussw.  Diat.,  p.  89,  T.  vi.,  fig.  76. 
Heibe^,  De  Danske  Ddat.,  p.  85. 

Ditch  near  town  of  Wexford.  Lower  Lake,  Eillamey,  Co.  Kerry. 
Lough  l^eagh,  near  Lurgan,  Co.  Armagh.  Cushendun,  Co.  Antrim. 
Derrylane  Lough,  Co.  Cavan.  Sub-peat  deposit,  Dromoro,  Co.  Down. 
Lough  Moume  deposit. 

NemeuHa  ammcana,  (Ehr.)    Fresh  water. 

Valve  linear,  oblong,  .nth  rounded  ends ;  length  '0085,  breadth 
*0010 ;  slightly  constricted;  cost®  fine,  convergent  in  the  middle,  and 
nearly  parallel  towards  the  ends;  intermediate  free  space  wide,  groatly 
expanded  in  the  middle;  central  nodule  large,  median  line  very 
strongly  marked.     (Plate  80,  fig.  30.) 

Ehr.  Mic.  T.  II.,  n.,  fig.  16.  Kitton,  Science  Gossip,  June,  1868| 
p.  131. 

This  species  in  a  fossil  state  is  widely  dispersed;  besides  the 
locally  indicated  by  Ehrenberg,  it  has  been  found  by  Mr.  Eitton  of 
l^orwich,  in  Perley's  Meadow  deposit,  Sth.  Bridgton,  Maine,  XT.  S.  A* 
I  found  it  in  great  abundance  in  a  frosh  water  deposit  discovered  by 
Dr.  Moss,  R.  !N.,  in  Vancouver's  Island,  as  also  in  a  sub-peat  deposit 
from  Dromore,  Co.  Down.  Eev.  George  Davidson  has  furnished  me 
with  specimens  found  in  a  fossil  state  in  Lough  Canmore,  near  Aber- 
deen. I  have  found  it  in  tolerable  abundance  in  a  living  state  in 
Lough  Keagh,  near  Lurgan,  Co.  Armagh. 

Nicmcula  uocephaia,  (Ehr.)    Frosh  water. 

Valve  long,  narrow;  length  -0055,  breadth  '0007 ;  undulate  on  the 
margin,  with  three  nearly  equal  and  slight  infiations;  ends  constricted 


352  PfVceedinffB  of  the  Bayal  Irish  Academy. 

and  capitate ;  cost»  atrong,  convergent  in  the  middle,  and  radiate  to- 
wards the  enda ;  intermediate  free  space  narrow,  except  in  the  middle^ 
where  it  is  much  expanded,  reaching  to  the  margin.  (Plate  80^ 
fig.  81.) 

•  Kiite.  Bac.,  p.  101,  without  a  figure.  This  author  identifies  the 
species  with  Pmnularia  isocephala,  £hr.  Kitton,  Science  Gbssip^ 
June,  1868,  p.  182. — ^Pinnularia  momle,  Bab.  Fl.  Eur.  Alg.,  sect.  i.» 
p.  220. 

Fond  near  the  city  of  Arma^.    Friarstown,  Co.  Ihiblin. 

Navicula  nodosa,  (Ehr.)    Fresh  water. 

Yalye  long  and  narrow ;  length  *0024,  fareadth  *0005 ;  margin  un- 
dulate, with  three  nearly  equal  inflations ;  costaB  short,  not  very  close, 
conYe]^;ent  in  the  middle,  radiate  towards  the  ends ;  intermediate  free 
space  wide,  expanded  in  the  middle.     (Plate  80,  fig.  26.) 

Kiita.  Bac.,  p.  101.  T.  xxviii.,  fig.  82.  This  author  regards  tho 
form  as  identical  with  Kavicula  nodosa,  Ehr.  Infus.,  1888,  p.  179,  T. 
xdi.,  fig.  9.  Bab.  Siissw.  Diat.,  p.  41,  T.  vi.,  fig.  86.  Gregory, 
Q.J.M.S.,  Yol.  iy.,  1856,  p.  8,  PI.  i.,  ^f;,  6.  Pinnxdaria  nodosa^ 
Wm.  Bm.,  B.D.,  Vol.  ii.,  p.  96. 

F^riarstown,  Featherbed  Mountain,  Co.  Dublin.  Biver  Slaney^ 
near  "Killurin.  Camolin,  Co.  Wexford.  Lake  near  Castlewcllan,  Co» 
Down.    Eilcool,  LugnaquiUa  Mountain,  Co.  Wicklow. 

Navicuta  nodosa,  var,  siaurcphora,  (Grunow).    Fresh  water. 

Yalye  smaller  than  in  the  typical  species ;  length  *0016,'  breadth 
•00025 ;  inflations  not  so  distinet ;  intermediate  free  space  expanding 
in  the  middle  into  a  distinct  stauroform  band  reachiDg  the  margin. 
(Plate  30,  fig.  26  a.) 

Kayioula  nodosa,  Grunow,  YerhaiuL  der  K.  K.  Zool.  Bot.  Geaell.^ 
Band  x.,  1860,  p.  521,  T.  ii.,  fig.  21. 

Ntmevla  hieapitata,  (O'Meara).    Fresh  water. 

Yalyes  small ;  length  *0020,  breadth  '0006 ;  linear,  attenuated 
towards  the  capitate  ends ;  costsB  fine,  conyei^ent  at  the  centre,  radiate 
towards  the  ends;  intermediate  free  space  narrow,  except  at  the 
middle,  where  it  is  roundly  expanded,  not  reaching  the  margin. 
(Plate  30,  fig.  82.) 

Pinnularia  biceps,  Gregory,  Q.  J.M.S.,  1856,  p.  8,  PL  i.,  fig.  28. 
Kiitzing  has  described  a  form  under  the  name  of  Nayicida  biceps,  Bao.^ 
p.  96,  T.  xxyiii.,  ^.  51,  which  is  widely  different  from  the  present. 
Gregory's  specific  name  must  therefore  be  dropped. 

Drumoughty  Lough,  near  Kenmare,  Co.  Cork.  Cawn  Lough^ 
near  Tralee,  Co.  Kerry.  Biyer  Bannow,  near  Clonegal,  Co.  Carlow. 
Xiloool,  Co.  Wicklow.     Camolin,  Co.  Wexford. 


(yMEARA — Report  on  the  Irish  Diatofnaoecs.  85S 

Ifimeula  hieapitaiay  var,  eruetfora,    Fresli  water. 

Yalre  linear  in  the  middle,  attenuated  towards  the  eapitfite  endisr. 
Length  *0024 ;  breadth  *0006.  Costse  fine,  radiate ;  intermediate  free 
space  narrow,  except  in  the  middle,  where  it  expands  into  a  narrow 
stauroform  band,  reaching  to  the  margin,  and  wider  there  than  at  the 
centre.     (PI.  80,  fig.  83.) 

Pinnnlaria  inteirapta,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  69,  PI.  xix., 
fig.  184.  "Were  it  not  for  the  figure  of  Smith,  just  referred  to,  it 
would  be  difficnlt  to  identify  this  form.  Smith  alleges  that  it  ia  iden- 
tical with  Stanroneis  parva,  Kiitz.  Bao.,  p.  106,  T.  xxix.,  fig.  23 ;  but 
that  form,  as  described  by  Kiitzing,  is  elliptical,  and  has  not  capitate 
ends,  in  consequence  of  which  I  consider  the  species  quite  distinct. 
The  specific  name  adopted  by  Smith  was  previonsly  appropriated  by 
Kiitzing  for  a  form  belonging  to  the  genus  Navicula,  which  that 
form  still  retains ;  for  which  reason  I  have  changed  the  specific  desig- 
nation.— ^Nayicula  parra,  Balfs,  inPritch.,  p.  897.  This  description  is 
giyen  obyiously  on  the  supposition  that  Pinnularia  interrupta,  ,(Wm. 
Sm.,)  was  identical  with  Stauroneis  parva,  Kiitz.  But  a  comparison 
d  the  figures  renders  the  accuracy  of  this  supposition  more  than 
doubtful. 

Pool  near  Olengarriff,  Co.  Cork.  Lough  Gill,  Co.  Kerry.  EtTor 
at  Port-na-Crush,  Co.  Donegal.  Ditch,  Cushendun,  Co.  Antrim. 
Gayagh,  Co.  Derry.    Pool  near  Glenchree,  Co.  Wicklow. 

Navicula  hieapilata,  var.  eonstrietay  (Grunow).     Fresh  water. 

Valves  slightly  incurved  in  the  middle;  ends  much  produced,  nar- 
rowed, and  but  slightly  capitate.  Length  *0025,  breadth  in  middle 
'0006.  CostsB  fine,  radiate.  Intermediate  free  space  narrow,  except 
in  the  middle,  where  it  expands  to  the  margin  in  a  narrow  stauroform 
band,  widening  at  margin.     (H.  30,  fig.  84.) 

Ifavicula  mesolepta,  var.  constricta,  Grunow,  Verhand.  der  K^  K. 
Zool.  Bot.  GeselL,  Band  x.,  1860,  p.  521,  T.  iv.,  fig.  22,  C.  Inas- 
much as  the  typical  form  of  Navicula  mesolepta  has  persistent  costc&i 
whereas  in  the  present  case  the  costs  are  obviously  interrupted  in  the 
middle,  I  prefer  to  regard  this  form  as  a  variety  of  Navicula  bicapitata. 

-  Featherbed  Bog,  Co.  Dublin.    Camolin,  Co.  Wexford. 

Nimeula  t&rmes,  (Ehr.)    Fresh  water. 

Valve  narrow,  oblong.  Length  '0035,  breadth  -0006;  slighthr 
incurved  in  the  middle;  ends  much  produced,  slightly  constricted. 
dostsB  short,  slightly  radiate ;  intermediate  free  space  wide,  sometimes 
Sdaching  the  margin  in  a  stauroform  band.     (PI.  30,  fig.  35.) 

Navicula  termes,  var.  nodulosa,  Kiitz.  Bao.,  p.  101,  T.  xxviii.,  fig.  ?!« 
in  which  the  costsa  are  represented  as  reaching  the  median  line^ 
whereas  in  the  present  form  they  are  marginal.    Kiitzing  regards  the 


946  Proceedings  of  the  Eoyai  Irish  Academy, 

NacicuJa  gilha^  (Ehr.)  Fresh  water. 
.  Valve  nearly  linear;  very  aliglitly  constrioted  towards  the  ends, 
and  very  gently  expanded  in  the  middle.  Length  about  *0044; 
breadth  about  '0008.  Strise  finely  coetate ;  convergent  in  the  middle, 
and  radiate  towards  the  ends.  Intermediate  free  space  narrow,  except 
in  the  middle,  where  it  is  roundly  expanded.     (Fl.  30,  fig.  19.) 

Kiitzing,  (Bac.,  p.  98,  T.  zxviii.  fig.  70),  has  described  a  form  under 
thifl  name,  which  he  regards  as  Pinnularia  gibba,  Ehr.  With  this  the 
form  so  named  by  Babenhorst  (Siissw.  Diat.,  p.45,T.  vi.,  fig.  27),  agrees. 
Ealfs'  description  seems  tolerably  well  to  correspond,  ''lanceolate, 
with  dilated  capitate  ends."  In  the  above  cases  the  figures  represent 
the  form  more  gibbous  in  the  middle  than  the  present  species,  and 
with  capitate  ends ;  the  stris  also  are  parallel,  while  in  the  present 
form  they  are  convergent  in  the  middle,  and  radiate  at  the  ends,  just 
as  Wm.  Bmith  has  figured  Pinnularia  gibba,  B.  D.  Vol.  i.,  p.  58,  PL 
zix.,  fig.  180.  The  present  form  is  less  capitate  at  the  ends,  and  the 
intermediate  free  space  more  roundly  expanded  in  the  middle  than  in 
Smith's  figure.  Grunow,  comparing  the  species  he  has  named  Navi- 
cula  gibba  with  Navicula  tabellaria,  says  it  stands  distinct  bom  it  "  by 
the  narrower  expansion  of  the  ends,  and  the  more  gradual  tapering  in 
the  middle."  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  517.    This  description  corresponds  exactly  with  the  present  form. 

Lough  Corrib,  Co.  Galway.  Drumoughty  Lough,  near  Kenmare^ 
Co.  CoriL  Cam  Lough,  near  Tralee,  Co.  Kerry.  Derrylane  Lough, 
Co.  Cayan.  Carrickmocreely  Hill,  Lugnaquilla  Mountain,  Bathdrum, 
Co.  Wicklow.  Featherbed  Mountain,  Co.  Dublin.  Lough  Moume 
deposit,  Co.  Antrim. 

Na/oieula  gibha,  var,  hoeckti,  (Bab.)    Presh  water. 

Valve  smaller  than  the  typical  species;  length  "0032,  breadth 
•0007 ;  margin  very  slightly  gibbous ;  ends  somewhat  capitate ;  strisB 
finely  costate ;  intermediate  free  space  narrow,  except  at  the  middle, 
where  it  expands  considerably,  sometimes  reaching  the  margin  at  one 
side,  but  not  at  the  other.     (Plate  00,  fig.  20.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  617,  T.  iv.,  fig.  17.  This  author  regards  the  form  as  identical  with 
Staurophora  pcckii,  Bab.  Bacil.  Sachs. 

Lough  Corrib,  Co.  Galway.    Pond  near  the  city  of  Armagh. 

Navieula  gibha,  var,  pan>a,  (O'Meara).     Fresh  water. 

Valve  small;  length  -0015,  breadth  -0003;  slightly  gibbous  at  the 
margins;  much  attenuated  towards  the  somewhat-capitate  ends;  stri» 
costate,  fine,  convergent  in  the  middle,  and  slightly  radiate  towards  the 
ends;  intermediate  free  space  relatively  broad,  expanding  at  the 
middle,  and  sometimes  reaching  to  the  mai*gin.     (Plate  30,  fig.  21.) 

There  is  a  form  somewhat  similar  to  this  described  by  Grunow 


O'Meara — Bqtart  on  the  Irish  DiatomacecB.  349 

under  the  name  of  NaTicnla  stanroptera,  var.  parva,  Yexliaiid.  der 
K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  517,  T.  iv.,  fig.  19.  The 
atriation  in  the  present  form  is,  howeyer,  coarser  than  in  Gh-onow's 
figure,  the  latter  also  being  more  robust,  for  which  reasona  I  hesitate 
to  identify  the  present  form  with  that  of  Grunow. 

Lough  IN'eagh,  near  Lurgan,  Go.  Armagh.  Gamolin,  Co.  Wez^ 
ford. 

NavicvJa  hemiptera,  (Kiitz).     Fresh  water. 

Talve  linear,  elliptical,  with  rounded  ends ;  length  *0025,  breadth 
•0005 ;  striae  costate  linear,  convergent  at  the  middle,  and  radiate  to- 
wards the  ends ;  intermediate  free  space  narrow,  somewhat  expanded 
in  the  middle.     (Plate  30,  fig.  22.) 

Kiitz.  Bac.,  p.  97,  T.  xxx.,  fig.  11.  Kalfs,  in  Pritch.,  p.  908; 
Grunow,  Yerhand.  derK.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  619. 
This  author  considers  the  form  may  be  only  a  variety  of  Navicula 
viridis,  which  it  greatly  resembles,  except  that  it  is  smaller,  and  the 
striation  very  much  nner.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  223. — ^Pinnularia  hemiptera,  Wm.'Sm.,  B.D.,  Vol.  ii.,  p.  95.  Eab. 
Siissw.  Diat.,  p.  42,  T.  vi.,  fig.  17.  Do.  Fl.  Eur.  Alg.,  sect.  i. 
p.  212. 

Luoan,  Featherbed  Mountain,  Friarstown,  Co.  Dublin.  Biver 
Enie,  near  Crossdoney,  Derrylaue  Longh,  Co.  Cavau,  Lough  Erne, 
Co.  Fermanagh.  Lough  Neagh,  near  Lurgan.  Ulster  Canal,  near 
Poyntzpass,  Co.  Armagh.  Pool  near  Glengamff,  Co.  Cork.  Streamlet, 
Cushendun,  Co.  Antrim.  Biver  Bann,  near  Coleraine,  Co.  Deiry. 
Sub-peat  deposit,  Di-omore,  Co.  Down. 

Naoieula  apieukUa,  (De  Br^b.)    Marine. 

Valve  linear  in  the  middle,  ^ttdnally  tapexing  towards  the  ends, 
which  run  out  into  acute  short  beaks ;  length  *0026,  breadth  -0008 ; 
cost®  fine,  converging  in  the  middle,  radiate  towards  the  ends ;  inter- 
mediate free  space  narrower  towards  the  ends,  expanded  in  the  middle. 
(PI.  30,  fig.  23.) 

Pinnularia  rostellata,  Gregory,  Diat.  of  Clyde,  p.  488,  PL  ix.,  fig. 
20,  1857. — ^Navicula  apiculate,  De  Br^bisson  Diat.  dn  Littoral  de 
Cherbourg,  p.  16,  PLi.,  fig.  5, 1867.  Ralfs,  in  Pritch.,  p.  903.  Donkin 
2^.  H.  Brit.  Diat.,  p.  56,  PI.  viii.,  fig.  6.  Kiitzing  has  described 
a  form  as  Navicula  rostellata,  which  is  quite  distinct  from  the  present ; 
it  is  therefore  necessary  to  drop  the  specific  name  adopted  by  Gregory, 
and  substitute  for  it  De  Br^bisson's  name,  Navicula  apiculata. 

Gregory  and  De  Br^bisson  describe  the  stris  as  reaching  the 
median  line ;  Donkin  more  correctly  represents  them  as  falling  short 
of  it,  but  does  not  describe  the  central  expansion  of  the  free  inter- 
mediate space. 

2B2 


866  Proceedings  of  the  Bayal  Irish  Academy/. 

Ifaineula  tnte^a,  (Wm.  Sm.)    Fresh  water. 

Valre  narrow,  elliptic,  mcurved,  then  angnlarlr  expanded  towarfg 
the  ends  which  are  narrow  and  papillate ;  striee  fine,  radiate ;  inter- 
mediate free  space  narrow,  except  at  the  middle,  where  it  is  slightly 
expanded.     (Plate  30,  fig.  43.) 

Balfs,  in  Pritch.,  p.  895,  who  describes  the  strise  as  reaching  the 
median  Une.  Donkin,  K.  H.  Biit.  Diat.,  p.  40,  PI.  vi.,  fig.  8,  where 
the  character  of  the  stnee  is  correctly  delineated. — ^Pinnularia  Integra, 
Wm.  Sm.,  B.D.,  Vol.  ii.,  p.  96.  Eab.  Fl.  Eur.  Alg.,  sect,  i, 
p.  220. 

Powerseonrt,  Co.  Wicklow. 

ITimcuIa  paehyeephah,  (BAh.)    Freshwater. 

YalTe  elliptical,  with  capitate  ends ;  length  *0022,  breadth  *0006 ; 
costsB  short,  conveigent ;  intermediate  free  space  broad,  reaching  the 
margin  in  a  narrow  stauroform  band.    (Plate  30,  fig.  44.) 

Pinnnlaria  pachycephala,  Bab,  Siissw.  Diat.,  p.  43,  T,  vi., 
fig.  40. 

Featherbed  Mountain,  Ballybrack,  Co.  Dublin. 

NavieuHa  suhcapttata,  (Gregory).    Fresh  water. 

Valve  narrow,  linear,  with  subcapitate  ends;  cost®  coarse  and 
distant;  intermediate  free  space  relatively  wide,  linear;  length  *0015j^ 
breadth  -0002.    (Phite  30,  fig.  45.) 

Balfs,  in  Pritch.,  p.  902. — ^Navioula  gracillima,  var.  subcapitata, 
Bab.  Fl.  Enr.  Alg.,  sect,  i.,  p.  200. — ^Pinnnlaria  subcapltata,  Gregory^ 
Q.  J.  M.  8.,  1856,  p.  9,  PI.  L,  fig.  30. 

Friarstown,  Featherbed  Mountain,  KiUakee,  Co.  Dublin.  Glencar» 
Co.  Kerry.     Lake  near  Castlewellan,  Co.  Down. 

Navieula  gracillima^  (Gregory).    Fresh  water. 

Valve  narrow,  linear,  with  pxt>duced  slightly  capitate  ends,  length 
•0018,  breadth  -00025;  cost®  very  fine,  convergent  in  the  middle^ 
slightly  radiate  towards  the  ends;  intermediate  free  space  narrow^ 
except  in  the  middle,  where  it  is  roundly  expanded.  (Plate  30^ 
fig.  46.) 

Balfs,  in  Pritch.,  p.  902.  Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  199. 
Schumann,  Diat.  der  Hohen  Tatra,  p.  70,  T.  iv.,  fig.  49. — Pinnularia 
gracillima,  Gregory,  Q.  J.  M.  S.,  1866,  p.  9,  PI.  i.,  fig.  81.  Wm.  Sm., 
B.  D.,  Vol.  ii.,  p.  95. 

Fiiarstown,  Piperstown,  Featherbed  Mountain,  Co.  Dublin.  Bath* 
drum,  LugnaquiUa  Mountain,  Co.  Wicklow.  Drumoughty  Lough, 
near  Kenmare,  Co.  Cork.  Glencar,  Co.  Kerry.  Lake  near  Castle- 
wellan, Co.  Down. 


O'MjRASLAr-^JRepaH  on  the  Irish  Diatomacem.  357 

Jfaoictda  macula^  (Oregoiy).    ICarine. 

Valve  broadly  elliptical,  with  narrowed  tnmcate  ends;  length 
*0014,  breadth  *  0008 ;  costsd  fine,  parallel ;  intermediate  free  space 
narrow,  except  in  the  middle,  where  it  expands  greatly  in  quadranga* 
lar  form.  -  <PIate  30,  fig.  47.) 

Gregory,  Q..J.M.  S.,  1866,  p.  43,  PL  v.,  fig.  9.  Ealfs,  in  Pritch,, 
p.  896.    Bab.  PL  Eur.  Alg.,  sect,  i.,  p.  189. 

Iiough  Gill,  Co.  Kerry, 

Jfavieula  neHetuie,  (Grunow).    Eresh  water. 

Valve  narrow;    length  -0016,   breadth  *0003;    ends  produced;* 
xnargin  triundulate ;  etcm  very  fine ;  intermediate  &ee  space  narrow, 
except  at  the  middle,  where  it  expands  in  a  short  nanx>w  staurof  orm 
band.    (Plate  30,  fig.  48.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860> 
p.  621,  T.  iii.,  fig.  34.    Bab.  Fl.  Eur.  Alg.,  sect.  1,  p.  207. 

Lough  Derryvaragh,  Co.  Westmeath.    Camolin,  Co.  Wexford. 

(c.)  Ciupidata. 

Vdhes  more  w  less  disiindfy  laneeohU;  ends  sometiniu  produced; 
median  Une  distinct;  intermediate  free  epace  narroto,  hounded  hj  two 
weH-defined  longitudinal  ridges^  one  on  either  eide  of  the  median  line. 

Ifavicula  cuspidata,  (Wm.  Smith).     Fresh  water. 

Valve  large,  lanceolate;  ends  cuspidate;  length  about  *0070, 
breadth  *0016;  stri®  dose,  fine,  linear,  parallel;  median  line  with 
slightly  elongated  expansions  near  the  central  nodule.  (Plate  31,  fig.  1.) 

Kiitz.  Bac.,  p.  94,  T.  iii.,  figs.  24  and  27.  Wm.  Sm.  B.  D.,  Vol. 
i.,  p.  47,  PI.  xvi.,  fig.  131.  Bab.  Sussw.  Diat.,  p.  37,  T.  vil,  fig.  16. 
This  latter  author  remarks,  that  this  form  is  very  like  Navicula  f ulva, 
but  never  attains  the  same  size.  This  observation  is  not  borne  out  by 
the  specimens  I  have  had  the  opportunity  of  examining ;  Navicula 
cuspidata  is  usually  the  larger,  sometimes  very  much  so.  Balfs,  in 
Ritch.,  p.  905,  PI.  xii.,  fig.  6.  Grunow,  Verhand.  der  K.  K.  Zool. 
Bot.  GeseU.,  Band  x.,  1860,  p.  628.  The  form  referred  to  by  Grunow 
may  possibly  be  different  from  the  present,  as  he  describes  the  strieo 
as  somewhat  radiate  in  the  middle ;  the  strise  in  N.  cuspidata  being 
parallel  all  through.  Eeiberg,  Be  Danske  Diat.,  p.  82.  Cleve,  Om 
Svenska  och  Korska  Biat,  p.  228.  Donkin,  K.  H.,  Brit.  Biat.,  p.  39, 
H.  vi.,  fig.  6. 

Castlebridge,  Tacumshane,  Co.  Wexford.  Berrylane  Lough, 
Stream,  Crossdoney,  Co.  Cavan,  Cushendun,  Co.  Antrim.  Pond, 
Botanic  Gardens,  Belfast,  Co.  Down.     Bellarena,  Co.  Berry.     Biver 


868  Proceedings  of  the  Eoyai  Irish  Academy. 

Dodder,   Co.    Dublin.    Lough  Gill,  Co.  Kerry.     Powersoouit^   Co. 
Wicklow.    Lough  Moume  deposit. 

Ifavictdafuha,    (Donkin).    Fresh  water. 

Valve  very  much  as  the  precediugi  but  smaller ,  and  having  the 
strisB    somewhat    radiate;   length  -0082,  breadth  -0007.    (PI.   31, 

There  is  great  difficulty  in  identifying  this  form  with  that  named 
Kavicula  fulva  by  Ehrenberg,  which  several  authors  identify  with 
Kavicula  cuspidata. 

This  latter  Smith  has  so  accurately  described,  that  there  is  no  diffi- 
culty in  identifying  it,  and  therefore,  under  the  circumstances,  I 
attribute  it  to  him.  Donkin,  too,  has  so  figured  Navicula  fulva  as 
to  render  it  equally  distinctive,  and  for  this  reason  I  assign  the 
species  to  him. 

Donkin,  N.  H.,  Brit.  Diat,,  p.  41,  PI.  vi.,  fig.  9. 

Lough  Gill,  Co.  Kerry.    Dysart,  Co.  Wateiford. 

Navieula  euapiSf  N.  8.    Marine. 

Valves  narrow,  lanceolate;  length  about  -0044,  breadth  about  -0008 ; 
longitudinal  sulci  dose  to  median  line.  Striae  linear,  slightly  radiate ; 
ends  cuspidate ;  dry  valve  a  light  straw  colour.     (PI.  81,  ^g,  3.) 

Prom  stomachs  of  Asddians,  Co.  Clare. 

JVavtctda  rhomhica.    (Gregory).    Marine. 

Frustules  on  front  view  subijuadrate ;  slightly  constricted  angles, 
rounded.  On  side  view,  valve  elliptical.  Striss  fine,  linear,  converging 
in  the  middle,  radiate ;  much  finer  and  closer  towards  the  ends ;  length 
'0026,  breadth  -0008.     (PI.  31,  fig.  4.) 

Gregory,  Q.  J.  M.  S.,  1856,  p.  38,  PI.  v.,  fig.  1.  Ealfs,  in  Pritch, 
p.  908.     Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  181. 

Barrow,  Co.  Wexford.  Malahide,  Co.  Dublin.  Lough  Gill,  Co; 
Kerry.  Seashore  near  town  of  Galway.  Breaches,  Co.  Wicklow. 
Stomachs  of  Ascidians,  Belfast  Lough,  Co.  Antrim.  Stomachs  of  Asci* 
dians,  Co.  Clare. 

Jfavieula  earu/ea,  N.  8.    Fresh  water.    * 

Valve  narrow,  lanceolate :  ends  much  produced.  Length  '0022^ 
breadth  -0005 ;  longitudinal  sulci  close  to  median  line.  .  Striss  linear^ 
convergent  in  middle,  slightly  radiate  towards  the  ends ;  dry  valve  of 
a  pale  colour.    (PI.  31,  fig.  5.) 

Lough  Mask,  near  Tourmakeady,  Co.  Mayo. 


O'Meara — Report  on  the  Irish  Diatomacm.  359 

Na/oieula  deeppiens,  N.  S.    Marine. 

Yalye  narrow,  elliptical,  rounded  at  ends ;  length  '0030,  breadth 
-0008.  Striie  fine,  close,  dightly  radiate ;  in  some  lights  apparently 
punctate ;  seemingly  disappearing  in  the  middle,  and  presenting  the 
appearance  of  a  narrow  staurof orm  band,  extending  to  the  margins ; 
thu  howeyer  is  deceptiye.     (PI.  31,  fig.  6.) 

Tide-pools,  Oalway  Bay,  near  the  town  of  Oalway. 

Naifictda  tummts,    (Wm.  Smith).    Brackish  or  marine. 

Yalye  elliptical;  ends  produced.  Length  from  *0024  to  '0040, 
breadth  from  '0010  to  '0015.  StrisB  fine,  punctate,  slightly  radiate ; 
when  not  exactly  in  focus  appearing  to  be  moniliform.     (PI.  31,  fig.  7.) 

Smith  has  correctly  described  the  character  of  the  stiisB  in  this 
species ;  but  the  figure  represents  the  strise  as  they  appear  when  not 
in  focus. 

Donkin,  N.  H.,  Brit.  Diat.,  p.  15,  considers  this  form  as  identical 
with  Nayicula  rostrata,  £lir.,  and  Nayicula  sculpta,  Ehr.  These 
forms  it  appears  were  found  by  Donkin  in  the  Bergmehl  of  Santa 
Fiore,  and  in  the  fossil  deposit  of  Franzensbad,  which  I  belieye  are 
both  fresh  water  deposits,  though  that  author  assigns  19'ayicula  ros- 
trata to  brackish  localities.  The  form  under  consideration  has  been 
found  by  Smith  only  in  brackish  water ;  and  I  haye  found  it  only  in 
localities  decidedly  brackish  or  marine.  Howeyer  similar  the  forms 
may  be,  they  seem  to  me  perfectly  distinct,  and  distinguishable  by 
this  feature,  that  in  Nayicula  tumens  the  strisa  run  uninterruptedly 
from  the  margin  to  the  longitudinal  sulci,  whereas  in  N.  rostrata  they 
are  interrupted,  and  present  an  unstriate  space  between  each  sulcus 
and  the  ends  of  the  striae.  Wm.  8m.,  B.  D.,  Vol.  i.,  p.  52,  PL  xyii., 
fig.  150.  Kalfs,  in  Pritch.,  p.  900.  Ghnnow,  Verhand.  der  K.  K.  Zool. 
Lot.  Gesell.,  Band  x.,  1860,  p.  541.    Kab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  192» 

Salt  ditch,  near  Newtownlimayady  Junction,  Co.  Londonderry. 
Salt  ditch,  near  the  town  of  G^way.  Seaweeds,  Salt  Hill,  Co. 
Dublin.     Salt  ditch.  Breaches,  Co.  "Wicklow.    Lough  Gill,  Co.  Kerry. 

Navieula  rostrata,     (Ehr.)     Fresh  or  brackish  water. 

Yalyes  elliptical,  produced  into  long  rounded  apices  ;  length 
•0046,  breadth  '0015.  Striae  punctate,  sHghtly  radiate,  disappearing^ 
in  the  middle  of  the  space  between  the  margin  and  the  longitudinal 
sulcus,  and  appearing  again  upon  the  edge  of  the  sulcus.  (PI.  31,  fig.  8.) 

There  is  some  doubt  as  to  whether  this  species  belongs  to  fresh 
or  brackish  water.  The  fact  that  Donkin  identified  the  form,  so  well 
delineated  by  him,  with  specimens  from  the  Santa  Fiore  deposit,  as  well 
as  that  of  Franzensbad,  would  seem  decisiye  as  to  its  proper  habitat 
being  in  fresh  water.  The  localities,  howeyer,  to  which  he  has 
assigned  the  species  found  by  him  in  a  Hying  state  are  brackish ; 


360  Proeeedinga  of  the  JEUiyal  Iriah  Academy. 

and  the  only  three  localities  in  which  I  have  found  it  in  Ireland,  it 
not  marine,  are  ceztainly  brackish. 

Kiits.  Bao.,  p.  94,  T.  iii.,  fig.  55,  who  attribates  the  ipecies  to 
Ehrenberg.  Balls,  in  Fritch.,  p.  901,  who  regards  it  as  distinot  from 
Nayicula  sculpta,  £hr.  Omnow,  Yerhand.  der  K.  E.  Zool.  Bot. 
Gesell.,  Band  x.,  1860,  p.  540,  who  states  that  he  did  not  find  the 
form  in  the  Santa  Fiore  BorgmehL  examined  by  him,  but  confirms 
Donkin's  statement  of  haying  obtainod  it  in  the  Franzensbad  deposit. 
Donkin,  N.  H.  Brit.,  Diat.,  p.  16,  PL  ii.,  fig.  9.  Bab.  FL  Eur.  Alg., 
sect,  i.,  p.  197. 

Seashore,  Queenstown,  Co.  Cork.  Breaches,  Co.  Wicklow.  Salt 
Hill,  Co.  Dublin. 

Naoieula  tmuiroitrU,  K.  8.     Marine. 

Valve  elliptical,  with  long  produced  narrow  apices;  length  *0018, 
breadth  «0006 ;  stnie  fine,  parallel  in  the  middle,  and  slighUy  radiate 
towards  the  ends ;  less  distmct  midway  between  the  margin  and  the 
longitudinal  sulcus ;  intermediate  free  space  narrow,  apparently  ex- 
panding in  the  middle  in  a  short  and  very  narrow  stauroform  band. 
(Plate  31,  fig.  9.) 

Stomachs  of  Ascidians,  Broadharen  Bay,  Co.  Galway. 

Navteula  amit^^tM,  (Ehr.)    Fresh  water. 

Valves  elliptical,  ends  produced  and  capitate;  length  '0082, 
breadth  '0010 ;  strisB  fine,  parallel.     (Plate  31,  fig.  10.) 

Kiitz.  Bac.,  p.  95,  T.  xxviiL,  fig.  66,  who  attributes  the  species  to 
Ehrenberg.  Wm.  Sm.,  B.  D.,  Vol.  L,  p.  51,  PI.  xvi.,  fig.  149.  Eab. 
SiisBW.  Diat.,  p.  40,  T.  vi.,  fig.  59.  Ealfs,  in  Pritch.,  p.  902.  Gru- 
now,  Verhand,  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  529,  T. 
iv.,  fig.  33.  Cleve,  Om  Svenska  och  l^orska  Diat.,  p.  228.  Donkin, 
N.  H.,  Brit.  Diat.,  p.  39,  PL  vi.,  fig.  6. 

Eiver  Erne,  near  Crossdoney,  Co.  Cavan.  Pool  near  Glencar,  Co. 
Cork.     River  Bann,  near  Coleraine,  Co.  Londonderry. 

Navieula  9pharophoraf  (Kiitz.)     Fresh  water. 

Valve  elliptical;  ends  considerably  produced  and  capitate;  stiiffi 
fine,  punctate,  slightly  convergent;  length  -0030,  breadth  *0010. 
(Plate  31,  fig.  11.) 

Kiitz.  Bac,  p.  95,  T.  iv.,  fig.  17.  Wm.  Sm.,  B.  D.,  VoL  L,  p.  52, 
PL  xvii.,  fig.  148,  who  represents  the  strias  as  moniliform,  an  appear- 
ance they  present  only  when  not  in  focus.  Rab.  Siissw.  Diat.,  p.  40, 
T.  vi.,  fig.  65a,  65b  being,  as  it  would  appear,  a  very  distinct  form. 
Ealfs,  in  Pritch.,  p.  899.     Grunow,  Verhand.  der  K.  K.  Zool.  Bot. 


O'Meara — Rqiort  on  the  Irish  Diatomacece.  361 

Gesell.,  Band  x.,  1860,  p.  640,  T.  iy.,  fig.  34.  Gleve,  Om  Svendca  ocli 
Norska  Diat.,  p.  227.  Donkia,  N.  H.  Brit.  Diat.,  p.  34,  PI.  v., 
fig.  10. 

Tacumshane,  Co.  "Wexford.  Lough  Gill,  Co.  Kerry.  Ifoist  rock, 
Portnisli,  Co.  Antrim.  Biver  Bann,  near  Coleraine,  Co.  London- 
deny. 

.   Navieula  quarnerensis,  (G^^unow).    Marine. 

Yalve  broadly  elliptical,  slightly  produced  towards  the  apicnlate 
ends ;  BtrisB  fine,  obscurely  punctate,  radiate ;  length  '0028,  breadUi 
•0012.     (Plate  31,  fig.  12.) 

Qrunow,  Verhand.  der  K.  K.  ZooLBot.  Gesell.,  Band  x.,  1860,  p. 
^30,  T.  iii.,  fig.  8,  found  in  the  Adriatic  Sea,  from  two  to  four  fathoms 
in  depth. 

Salt  ditch,  near  QdlwBj  town.  Stomachs  of  Ascidians,  Boundstone 
Bay,  Stomachs  of  Ascidians,  Broadhayen  Bay,  Co.  Gkdway. 

Navicul<i  Davidsonianay  N.  S.    If  arine. 

Yalye  broadly  elliptical ;  ends  slightly  produced,  apicnlate ;  strisa 
fine,  linear,  parallel  in  the  middle,  and  slightly  radiate  towaids  the 
ends ;  central  nodule  large,  elongate,  longitudinal ;  sulci  yery  distinct, 
slightly  expanded  in  the  middle.    (Plate  31,  fig.  13.) 

From  stomachs  of  Ascidians,  Co.  Clare. 

Nwieula  ovulum,  ^Grunow).    Marine. 

Yalye  broadly  elliptical ;  strise  fine,  linear,  slightly  radiate  in  the 
middle,  and  more  so  towards  the  ends;  longitudinal  sulci  strongly 
marked,  and  quite  parallel  through  their  entire  length;  central  nodule 
small;  colour  of  dry  frustule  pale  yellow;  length  '0024,  breadth 
•0011.     (Plate  31,  fig.  14.) 

GruDow,  Yerhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  619,  T.  iii.,  fig.  19. — ^NaTicula  litoralis,  Donkin,  K  H.  Brit.  Diat., 
p.6,  Pl.i.,fig.2. 

Malahide. 

(d.)  Zatiu8CuJa, 

Valves  generally  elliptical;  ends  sometimes  produced;  stria  Jtne; 
intermediate  free  space  generally  hroad,  and  expanded  in  the  middle;  a 
suhmarginal  langitudinal  iulcua  more  or  less  distinctly  developed, 

Ndvicula  latiuscula,  (Ziitz.)    Fresh  water. 

Yalve  broadly  elliptical;  striaa  delicate,  parallel;  length  about 
'0048,  breadth  *0014;  intermediate  free  space  much  expanded. 
{Plate  31,  fig.  16.) 

£iitz.  Bac.,  p.  93,  T.  y.,  fig.  40.    This  form  could  scarcely  have 


362  Proceedings  of  the  Royai  IrUh  Academy. 

been  identified,  were  it  not  that  authentic  specimens  were  seen  by 
Wm.  Smith,  who  considers  it  identical  with  his  Nayicnla  patula^ 
B.  D.,  Vol.  i.,  p.  49,  PL  xri.,  fig.  139.  Ralls,  in  Flitch.,  p.  905.  Bab. 
Siissw.  Biat.,  p.  38,  T.  yi.,  fig.  61.  If  in  this  case  the  figure  b^  cor- 
rect, it  can  scarcely  be  identified  with  Nayicnla  latinscula,  Kiitz* 
Gninow,  Yerhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  z.,  1860,  p.  634,. 
T.  ir.,  fig.  38.  Donkin,  N.  H.,  Brit.  Diat.,  p.  27,  PI.  ir.,  fig.  7.  Eab. 
Fl.  Eur.  Alg.,  sect;  i.,  p.  182. 

Longh  Corrib,  Co.  Galway.  Eillnrin,  Co.  Wexford.  Newtown- 
limarady,  Co.  Deny.    Breaches,  Newcastle,  Co.  Vicklow. 

Navieida  harheriana,  N.  S.    Marine. 

Yalre  linear,  elliptical,  gradually  attenuated  towards  the  produced 
ends;  strie  linear,  fine,  close,  distinctly  radiate;  intermediate  free 
space  wide,  greatly  expanded  in  the  middle ;  median  terminating  to« 
wards  the  central  nodule  in  elongated  expansions;  length  '0052^ 
breadth  -0014. 

This  form  might  be  easily  confounded  with  Nayicula  latiuscula^ 
from  which  it  dilPers  in  the  following  features :  the  intermediate  free 
space  is  much  wider,  the  ends  are  produced,  and  the  striss  are  radiate,, 
and  somewhat  coarser.     (Plate  31,  fig.  16.) 

On  sea-weeds,  Dalkey,  Co.  Dublin.  Breaches  near  Newcastle,  Co. 
Wicklow.  In  both  these  gatherings  there  was  a  considerable  admix- 
ture of  fresh  water  forms;  the  marine  forms,  howeyer,  greatly  prepon- 
derated. 

Kavicula  grunovii,  (O'Meara).     Fresh  or  brackish  water. 

Yalve  broadly  elliptical,  longitudinal,  marginal  sulci  very  distinct ;. 
intermediate  free  space  wide,  lanceolate,  greaUy  expanded  in  the  mid- 
dle ;  median  line  slightly  undulate ;  striad  fine,  slightly  radiate  ; 
length  -0040,  breadth  -0016.     (Plate  31,  fig.  17.) 

Navicula  elegans,  Orunow,  Yerhand.  der  K.  K,  Zool.  Bot.  G^esell., 
Band  x.,  1860,  p.  534,  T.  ir.,  fig.  37.  This  author  confounds  this 
form  with  Nayicula  elegans,  Wm.  8m.,  of  which  he  states  he  had 
never  seen  a  specimen  ;  and  suggests  that  in  case  it  should  prove  to  be 
different  from  the  last-named  species  it  should  be  designated  Navicula 
lacustris.  Cleve,  in  his  Diatoms  of  the  Arctic  Sea,  p.  17,  perceiving 
that  the  form  was  obviously  distinct  from  Navicula  elegans,  adopts 
Gmnow's  alternative  designation,  which,  however,  must  be  aban- 
doned, as  the  name  had  been  appHed  by  Qregorv  to  designate  a  very 
different  form.  Grunow  found  this  species  in  fresh  water  as  well  as 
in  slightly  brackish  water,  so  that  there  is  a  difficulty  in  ascertaining 
the  habitat.  I  cannot  clear  up  this  difficulty,  inasmuch  as  the  only 
gathering  in  which  the  form  occurred  to  me  contained  both  marine  and 
fresh  water  forms. 

Bellarena,  Co.  Derry. 


O'Meara — Repw*t  on  the  Irish  Diatomaceco,  363 

Navicula  amphMcsna,  (Bory).     Fresh  water. 

Valve  broadly  elliptical,  with  produced  capitate  ends,  longitudinal 
sulci  close  to  the  margin ;  intermediate  free  space  lanceolate,  broad 
in  the  middle.  Strise  fine,  linear,  close,  radiate ;  length  '0035, 
breadth  -2013.     (PI.  31,  ^.  18.) 

Kiitz.  Bac,  p.  95,  T.  iii.,  figs.  41  and  42.  This  author  regards 
the  species  as  identical  with  Navicula  amphisbeena,  Bory,  1824,  to 
whom,  therefore,  it  should  be  attributed.  tVm.  Sm.,  B.  D.,  Yol.  i.,  p. 
51 ,  PI.  xvii.,  fig.  147.  Kalfs,  in  Pritch.,  p.  899,  PI.  vii.,  fig.  72.  Rab. 
Susaw.  Biat.,  p.  40,  T.  vi.,  fig.  66.  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  36.  Heiberg,  De  Danske  Biat., 
p.  82.  Cleve,  Om  Svenska  och  Norska  Biat.,  p.  227.  Bonkin,  N.  H. 
Brit.  Biat.,  p.  36,  PI.  v.  fig.  13. 

Biver  Bodder,  Bundrum,  Blackrock,  Malahide,  Co.  Bublin.  River 
Bann,  Coleraine,  Bellarena,  Co.  Berry.  Caumlough,  near  Tralee. 
Lough  GKll,  Co.  Kerry.  Breaches,  near  Newcastle,  Co.  Wicklow. 
Tacumshane,  Co.  Wexford. 

Nacicula  suhsaltna,  (Ehr.)     Brackish  wat^r. 

In  all  respects  resembling  I^avicula  amphisbsena,  except  that  the 
ends  are  not  capitate,  nor  so  much  produced. 

Bonkin,  N.  H.  Brit.  Biat.,  p.  24,  PI.  iv.,  fig.  2.— Navicula  am- 
phisbaena,  var.  fi.  Wm.  Sm.,  B.B.,  Vol.  i.,  p.  51;  PI.  xvii.,  ^g.  147  /?. 
The  last-named  author  attributes  the  species  to  Ehrenberg.  Cleve, 
Biatoms  from  Arctic  Sea,  p.  18.  This  form  occurs  frequently,  mixed 
with  Navicula  amphisbsena,  in  places  accessible  to  marine  influences, 
but  I  have  never  found  it  in  perfectly  fresh  water.  So  that,  with 
Bonkin,  I  am  disposed  to  consider  it  may  be  a  distinct  species. 

Tacumshane,  Co.  Wexford.  Breaches,  Co.  Wicklow.  Caumlough, 
near  Tralee.     Lough  Gill,  Co.  Kerry.     Malahide,  Co.  Bublin. 

Na/victda  elegant ,  (Wm.  Sm.)     Marine  or  brackish  water. 

Valve  elliptical,  lanceolate ;  longitudinal  sulci  marginal.  6tri» 
distinct,  linear,  convergent  in  the  middle,  afterwards  radiate ;  inter- 
mediate free  space  narrow,  except  in  the  middle,  where  it  expands 
considerably;  length  about  -0038,  breadth  about  '00065.  (PI.  31, 
fig.  19.) 

Wm.  Sm.  B.  B.,  Vol.  i.,  p.  49.  PI.  xvi.  fig.  137.  Ralfs,  in  Pritch., 
p.  907.  Heiberg,  Be  Banske  Biat.,  p.  85.  Rab.  PL  Eur.  Alg.,  sect. 
i.,  p.  182.  Bonkin,  N.  H.  Brit.,  Biat.,  p.  23,  PI.  iv.,  fig.  1.  This 
form  is  obviously  distinct  from  that  described  under  the  name  of  Navi- 
cula elegans  by  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band 
X.,  1860,  T.iv.,  fig.  37. 

Blackrock,  Co.  Bublin.  Caumlough,  near  Tralee.  Lough  Gill, 
Co.  Kerry.  Galway  Bay.  Breaches,  Kilcool,  Co.  Wicklow.  Tacum- 
shane, Co.  Wexford. 

B    I.  ▲.  PROC,  SBB.  n.,  TOL.  11.,  SCIBlfCI.  2  S 


364  Proceedings  of  the  Royal  Irish  Academy. 

Navicula  patpehralis,  (DeBr^b.)    Marine. 

Valve  broadly  elliptical,  lanceolate  at  the  ends ;  striae  distinctly 
costate,  linear,  radiate,  marginal ;  intermediate  free  space  wide,  ellip- 
tical-lanceolate ;  length  -0034,  breadth  -0013.     (PI.  31,  fig.  20.) 

Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  50.  Supp.,  PI.  xxxi.,  fig.  273.  The 
figure  represents  the  striae  as  minutely  punctate ;  in  reality  they  are 
strongly  costate.  Ralfs,  in  Pritch.,  p.  905.  Grunow,  Verhand.  der 
K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  160,  p.  536,  T.  iii.,  fig.  27.  The 
form  here  described  exactly  resembles  that  of  Smith,  being  very  small, 
and  with  minutely  punctate  striae.  Donkin,  N.  H.  Brit.  Diat.,  p.  25, 
fig.  3.  This  author  regards  the  species  as  identical  with  Navicula 
barclayana,  Greg.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  182,  who  describes 
the  striae  as  distinctly  granulate. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Arran  Islands,  Co.  Gbl- 
way. 

Navicula  angutosaj  (Greg.)     Marine. 

Similar  to  the  preceding,  but  striae  finer  and  closer,  and  longer, 
convergent  in  the  middle,  radiate  towards  the  ends;  intermediate 
free  space,  instead  of  being  elliptical,  is  lanceolate  ;  length  '0050, 
breadth  -0010. 

Gregory,  Q.  J.  M.  8.,  1856,  p.  42,  PI.  v.,  fig.  8.  Ralfs,  in  Pritch., 
p.  905.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  176.  Donkin,  N.  H.  Brit. 
Diat.,  p.  26,  PI.  iv.,  fig.  4. 

River  Slaney,  Killurin,  Tacumshane,  Co.  Wexford.  Breaches, 
near  Newcastle,  Co.  Wicklow.  Malahide,  Co.  Dublin.  Arran  Islands, 
Co.  (Mway. 

Navicula  aemiplenay  (Gregory).     Marine. 

Valve  as  in  the  preceding  form,  but  much  narrower,  and  the  in- 
termediate free  space  not  angular  in  the  middle. 

Donkin,  N.  H.  Brit.  Diat.,  p.  26,  PI.  iv.,  fig.  5. — Pinnularia  an- 
gulosa,  var.  /?,  Gregory,  Q.  J.  M.  8.,  1856,  p.  42,  PI.  v.,  fig.  8*— 
Pinnularia  semiplena,  Greville,  Q.  J.  M.  S.,  1859,  p.  84,  PI.  vi.,  fig.  12. 

Malahide,  Co.  Dublin.  Fintragh  Bay,  Co.  Donegal.  Rostrevor, 
Co.  Down. 

Navicula  hehes,  f Ralfs).     Fresh  water. 

Valve  gibbous  in  the  middle,  ends  somewhat  attenuated,  but 
still  broad,  and  rounded.  Striae  fine,  linear,  nearly  parallel  ;  interme- 
diate free  space  wide  in  middle,  lanceolate  towards  the  ends.  (PI. 
31,  fig.  21.) 

Ralfs,  in  Pritch.,  p.  896,  who  regards  the  species  as  identical  with 
Navicula  obtusa,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  50,  PI.  xvi.,  fig.  140, 
with  which  I  find  it  impossible  to  identify  it.  Donkin,  N.  H.  Brit., 
Diat.,  p,  23,  PI.  iii.,  fig.  12. 

Marl,  Co.  Down.     Lough  Moume  deposit. 


O'Meara — Report  on  the  Iriah  Diatofnaeecp.  365 

I^avieula  lineata,  (Donkin).     Marine. 

Valve  linear,  elliptical,  with  cuneate  ends;  margin  slightly 
curved.  Striae  strong,  convergent  in  the  middle,  and  radiate  towards 
the  ends ;  longitudinal  sulcus  dividing  the  striae  into  two  nearly  equal 
parts;  intermediate  free  space  broad,  lanceolate  towards  either 
end,  and  expanded  in  the  middle ;  length  about  *0034,  breadth 
about  0010.     (PI.  31,  fig.  22). 

Donkin,  Q.  J.  M.  8.,  1859,  p.  32,  PI.  iii.,  fig.  17.  Also  N.  H., 
Brit.  Biat.,  p.  8,  PI.  i.,  fig.  8. 

Seashore  near  the  town  of  Galway. 

Navieula  l^er,  (Wm.  Sm.)    Marine. 

Yalve  narrow  elliptical,  with  rounded  ends.  StrisB  fine,  slightly 
radiate,  divided  into  two  nearly  equal  portions  by  the  longitudinal 
sulcus;  intermediate  free  space  narrow  towards  the  ends;  slightly 
expanded  in  the  middle ;  length  from  '0030  to  '0045,  breadth 
from  0009  to  0012.     (PI.  31,  fig.  23.) 

Wm.  Sm.,  B.  D.,  Vol.  i.  p.  48,  PI.  xvi.,  fig.  133.  Ealfs,  in 
Pritch.,  p.  907.  Grunow,  Verhand.  der  Zool.  Bot.  Gesell.,  Band  x., 
1860,  p.  547.  Cleve,  Om  Svenska  och  Norska  Diat.,  p.  227.  Kab. 
Fl.  Eur.  Alg.,  sect,  i.,  p.  180.  Donkin,  N.  H.  Brit.  Diat.,  p.  62, 
PI.  ix.,  fig.  5. 

Salt  ditch,  near  the  town  of  Wexford.  Lough  Gill,  Co.  Kerry. 
Seaweeds,  Kilkee,  Co.  Clare.  Lough  Foyle,  near  Newtownlima- 
vady,  Co.  Deiry.  Breaches,  near  Newcastle,  Co.  Wicklow.  Galway 
Bay. 

Navieula  hieuneata,  (Gmnow).     Marine. 

Valve  deeply  constricted  in  the  middle,  with  long  cuneate  ends, 
somewhat  rounded  at  the  apex.  Strise  linear,  parallel ;  longitudinal 
sulcus  nearer  to  the  median  line  than  to  the  margin ;  intermediate 
free  space  narrow,  except  in  the  middle,  where  it  is  slightly  ex- 
panded ;  median  line  strongly  developed ;  central  nodule  small, 
roundish;  length  '0056,  breadth  at  the  shoulders  '0018,  at  the 
middle  '0015.     (PI.  31,  fig.  24.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  546,  T.  iii.,  fig.  4.  This  author  considers  the  form  may  be  only  a 
variety  of  Navicula  liber,  from  which,  however,  it  differs  both  in 
form  and  structure.  The  strise  in  this  are  parallel,  in  Navicula 
liber  slightly  radiate.  My  specimens  are  generally  wider  at  the 
shoulders,  and  more  constricted  than  Grunow's  figure  represents  them. 
Cleve,  Om  Svenska  och  Norska  Diat.,  p.  227,  T.  i.,  figs.  3  and  4. 
The  form,  as  represented  by  this  last-named  author,  is  even  less 
constricted  than  Grunow's  figure  represents  it.  Cleve  remarks : — 
"Gmnow  has  not  described  the  front  view,  which  in  the  specimens 
examined   by   me   were   cuneate,  as   is  the   case  in  Gomphonema 

SS2 


366  Proceedings  of  the  Royal  Irish  Acadetny, 

or  Novilla ;  for  which  reason  this  species  ought  to  be  transferred  to  a 
new  genus,  distinguished  from  Navicula  by  the  cuneate  front  view. 
The  side  view  was  sufficiently  conformable  with  Gninow's  description." 
The  cuneate  appearance  of  the  front  view  just  referred  to,  I  am 
inclined  to  think,  was  casual,  arising  from  the  separation  of  the 
valves  at  one  end,  while  at  the  other  end  they  retained  their 
normal  position.  In  the  specimen  I  was  able  to  observe  on  the 
front  view,  there  was  but  a  single  valve,  which  did  not  exhibit  any 
tendency  to  a  cuneate  outline. 

Stomachsof  AscidianSyBoundstoneBay,  Arran  Islands,  Co.  Galway. 
Bantry  Bay,  Co.  Cork. 

Na/cieula  grUndUriana^  N.  S.    Marine. 

Valve  linear  elliptical ;  somewhat  cuneate  at  the  ends  ;  interme- 
diate free  space  narrow,  except  in  the  middle,  where  it  expands  into 
a  broad,  subquadrangular  area.  Stris  linear,  slightly  radiate ;  longi* 
tudinal  sulcus  marginal.     (PI.  31,  fig.  25.) 

This  form  strongly  resembles  a  Navicula  figured  by  Schmidt,  Atlas, 
T.  vi,,  figs.  31  and  32 ;  and  by  this  author  attributed  to  Griindler. 
It  diifers  however,  inasmuch  as  the  striae  in  the  latter  are  described 
as  punctate;  in  the  present  case  they  are  linear.  The  free  area 
around  the  central  nodule  in  this  form  is  much  larger  than  in  that 
figured  by  Schmidt.  The  strong  similarity  has  suggested  the  specific 
name. 

The  present  form  upon  first  view  might  be  easily  confounded  with 
Navicula  macula,  Greg.,  from  which  it  may  be  discerned  by  the 
fact  that  the  ends  in  the  latter  are  contracted  and  rounded ;  in  this 
they  are  cuneate.  The  striae,  too,  in  this  are  very  much  coarser  and 
more  distant  than  in  Nav.  macula. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

(e)  Zimoia, 

L&ngitudifuU  add  more  numerous  than  in  tJie  laaty  and  generally  more 
highly  developed:  intermediate  free  space  narrow. 

Navieula  iridisy  (Ehr.)    Freshwater. 

Yalve  linear,  elliptical,  rounded  off  at  the  ends.  Striae  fine,  Linear, 
parallel ;  intermediate  free  space  narrow  towards  the  ends,  expanded 
in  the  middle  ;  length  from  *0046  to  -0072,  breadth  from  -0010 
to  '0016.  Longitudinal  strise  distinct  at  the  margin.  (PI.  31, 
fig.  26.) 

Kiitz.  Bac,  p.  92,  T.  xxviii.,  fig.  42.  Kalfs,  in  Pritch.,  p.  907. 
Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  171.  Donkin,  N.  H.  Brit.  Diat., 
p.  30,  PI.  v.,  fig.  6.— Navicula  firma,  Vm.  8m.,  B.  D.,  Vol.  i.,  p.  48, 


O'Meara — Report  on  the  Irish  DiatomacecB,  367 

PI.  xvi.,  fig.  138.  Smith's  figure  does  not  represent  the  longitudinal 
striae,  which  more  particularly  characterize  this  species.  Kiitzing's 
fitrure,  though  representing  this  peculiarity,  does  not  give  to  it  its  due 
l)romintnce. 

Brumoughty  Lough,  near  Kenmare,  Co.  Cork.  Marsh,  Kilcool, 
(fl(»nmalure,  Co.  Wicklow.  Lower  Lake,  Killamey,  Co.  Kerry. 
Ditch,  Cushendun,  Co.  Antrim.  Pond  in  Botanic  Gardens,  Belfast. 
Lough  Moume  deposit,  Co.  Down. 

Tar.  amphigomphun,  (Ehr.)     Fresh  water. 

Like  the  typical  form  in  its  general  characters,  hut  linear  in  its 
outline  and  cuiicate  at  the  ends ;  length  from  -0025  to  "0045,  hreadth 
from  -0010  to  -0016.     (Plate  31,  fig.  27.) 

Kutz.  Bac,  p.  93,  T.  xxviii.,  fig.  40.  Rah.  Siissw.  Diat.,  p.  38, 
T.  vi.,  fi^,  47. — Xavicula  firma,  Ralfs,  in  Pritch.,  p.  909.  Donkin, 
X.  H.  Brit.  Diat.,  p.  31,  PI.  v.,  fig.  7. — Xavicula  firma,  var.  cuneata, 
Lagerstcdt,  ISiitv.  Diat.  friin  Spetsbergen  och  Beeren  Eiland,  p.  29. 

Lower  Lake,  Killamey,  Co.  Kerry.  Piperstown,  Co.  Dublin. 
Iliver  Erne,  netu-  Crossdoney,  Co.  Cavan.     Kilcool,  Co.  Wicklow. 

Var.  aJfinUy  (Ehr.)     Fresh  water. 

Valve  like  (lie  ty])ical  s])('('ies,  but  narrow  and  linear  in  outline ; 
4'nds  produced,  broud,  rounded,  and  slightly  constricted.  (Plate  31, 
1^%^  28.) 

Ka\icula  aflfinis,  Kiitz.  Bac,  p.  95,  T.  xxviii.,  fig.  65,  who  attri- 
butes the  spt  ( irs  to  Elinnbcrir.  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  50,  PL 
xvi.,  tig.  1 13.  Kalfs,  in  rritch.,  p.  902,  PI.  xii.,  fig.  32.  Rab.  Siissw. 
Diat.,  p.  40,  T.  vi.,  fisr.  58.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  21.>H.  Donkin.  N.  H.  Brit.  Diat.,  p.  33,  PL  v.,  fig.  8.  Lagerstedt, 
SJtv.  Diat.  fiiiu  Sp(l>bti'gen  och  Beeren  Eiland,  p.  29. 

River  Erne,  near  Crossdoney,  Co.  Cavan.  Drumoughty  Lough, 
near  Kenmare,  GlenirMnift',  Co.  Cork.  Bellarena,  Co.  Derry.  Pond, 
Botanic  Garlens,  Bi  it'ast,  Co.  Down.  Near  Newcastle,  Kilcool, 
Lugnaquilia  mountain,  Co.  Wicklow.     Killakee,  Co.  Dublin. 

K<nicula  duhia,  fEhr.)     Fresh  water. 

Valve  like  tliat  of  Xavicula  iridis,  var.  amphigomphus,  but  much 
smallrr  and  broa'ler  in  proportion;  the  cuncate  ends  extended  into 
nboil  a]M(Os;  striir  in  many  .specimens  seen  very  slightly  radiate; 
len'zth  -UOIS,  bna-lth  "0008.     (Plate  31,  tig.  29.) 

N.i\iula  (lui.ia,  Kiitz.  Bac,  p.  96,  T.  xxviii.,  fig.  61,  who  attri- 
but<*s  the  .s])(  cii-s  to  Elnvnlnrg.  Rab.  Siis.sw.  Diat.,  p.  40,  T.  vi.,  fig. 
60.  This  hitter  tigiire  is  quite  unlike  the  present  species.  Ralfs, 
in  Prit<  h.,  p.  902.  Donkin,  N.  H.  Brit.  Diat.,  p.  30,  PI.  v.,  fig.  5.— 
Jsavicula  ptisonis,  Grunow,  Verhand.  der  K.  K.,  Zool.  Bot.  Gesell., 


368  Proceedings  of  the  Boyal  Irish  Aeadefny. 

Band  z.,  1860,  p.  644,  T.  iii.,  fig.  28 :  and  likely  also  identical  with 
Navicula  limosa,  var.  bicnneata,  Onmow,  Ycrhand.  der  K.  K.  Zool. 
Bot.  Geeell.,  Band  x.,  1860,  p.  645,  T.  v.,  fig.  7. 

Lough  Mask,  near  Tourmakeady,  Clo.  Mayo.  Xilcool,  Co.  Wick- 
low.  Lough  Grill,  Co.  Kerry.  Pond  in  Botaiiical  Gardens  of  Trinity 
College,  Dublin. 

Navicula  limoMj  (Kiitz.)     Fresh  water. 

Valve  triundulate  on  the  margin,  more  expanded  in  the  middle 
than  at  the  ends ;  ends  cuneate ;  stria)  fine,  parallel ;  longitudinal  free 
space  narrow,  except  in  the  middle,  where  it  is  slightly  expanded; 
longitudinal  strias  easily  observed,  with  good  illumination;  length 
about  0034,  breadth  in  the  middle  0006.     (Plate  31,  fig.  30.) 

Kutz.  Bac,  p.  101,  T.  iii.,  fig.  60.  Bab.  Sussw.  Biat.,  p.  41,  T. 
vi.,  fig.  31.  Ealfs,  inPritch.,  p.  894,  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  544,  T.  v.,  fig.  86.  Donkin, 
N.  H.  Brit.  Diat.,  p.  73,  PL  xii.,  fig.  61.  Cleve,  Om  Svenska  och 
Norska  Diat.,  p.  227.  Lagerstedt,  Sotv.  Diat.  fran  Spetsbergen  och 
Beeren  Eiland,  p.  30,  T.  i.,  fig.  6. 

Powerscourt,  Co.  Wicklow.  Botanical  Gardens  of  Trinity  College, 
Dublin. 

Var,  gihh&ruia,  (Kilts.)    Fresh  water. 

Like  the  typical  species,  differing  only  in  this,  that  the  ends  instead 
of  being  cuneate  are  rounded. 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  544,  T.  v.,  fig.  8a.  Donkin,  N.  H.  Brit.  Diat.,  p.  73,  PI.  xii.,  fig.  6a. 
— Navicula  gibberula.  Kiitz.  Bac,  p.  101,  T.  iii.,  fig.  60.  Wm.  Sm., 
B.D.,  Vol.  i.,  p.  61,  PL  xvii.,  fig.  160.  Schumann,  Diat.  der  Hohen 
Tatra,  p.  76.  Lagerstedt,  Sotv.  Diat.  fran  Spetsbergen  och  Beeren 
Eiland,  p.  38. 

Biver  Erne,  Crossdoney,  Derrylane  Lough,  Co.  Cavan.  Glengar- 
riff,  Co.  Cork.  Lough  Neagh,  near  Lurgan,  Co.  Armagh.  Streamlet 
in  Powerscourt  demesne,  Co.  Wicklow.     Lough  Moume  deposit. 

Tor,  truncataj  (Kiitz.)     Fresh  water. 

Valve  nearly  linear,  with  rounded  ends;  the  longitudinal  sulci 
waved;  length  0025,  breadth  -00055.     (Plate  31,  fig.  31.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  545,  T.  v.,  figs.  8e  and  9. — Navicula  truncata,  Kiitz.  Bac,  p.  96, 
T.  iii.,  fig.  34,  and  T.  v.,  fig.  4.  Bab.  Sussw.  Diat.,  p.  39,  T.  vi., 
fig.  67. 

Friarstown,  River  Dodder,  Co.  Dublin.  Lough  Neagh,  near  Lur- 
gan, Co.  Armagh.  Lough  Mask,  near  Tourmakeady,  Co.  Mayo. 
Du^dalk,  Co.  Louth.  Wet  rock,  Ballyshannon,  Co.  Donegal.  Castle- 
Gregory,  Co.  Keny. 


O'Meara — Report  an  the  Irish  DiatamacecB.  369 

Na^icfda  undoua^  (Ehr.)    Fresh  water. 

Yalye  broadly  elliptical,  slightly  triondulate ;  apices  produced, 
very  narrow,  and  slightly  capitate ;  longitudinal  strisB  distinct ;  trans- 
verse strisB  obscure ;  length  -0016,  breadth  -0006.     (Plate  31,  fig.  32.) 

Kiitz.  Bac.,  p.  101,  T.  xxviii.,  fig.  83.  Rab.  Siissw.  Diat.,  p.  41, 
T.  vi.,  fig.  56. 

Biver  Erne,  near  Crossdoney,  Co.  Cavan. 

Na/vicuila  esoXy  (Ehr.)     Habit,  doubtful. 

Valve  lanceolate,  with  an  angular  expansion  in  the  middle;  margin 
slightly  triundulate;  ends  cuneate;  stnae  distinct,  linear,  punctate, 
nearly  parallel  in  the  middle,  slightly  radiate  and  closer  towards  the 
ends ;  median  line  strongly  devdopcd ;  terminal  nodules  at  some  dis- 
tance from  the  ends;  length  '0034,  breadth  0010.  (Plate  31, 
fig.  33.) 

Kiitz.  Bac,  p.  94,  T.  xxviii.,  fig.  53,  who  regards  the  species  as 
identical  with  Pinnularia  esox,  I^.  Balfs,  in  Pritch.,  p.  896,  PI. 
xii.,  fig.  43.  The  description  in  this  case  is  tolerably  accurate,  but 
the  figure  is  incorrect. — ^Pinnularia  esox,  Rab  Siissw.  Diat.,  p.  45, 
T.  vi.,  fig.  7.  This  figure  does  not  at  all  represent  the  peculiarities 
of  the  species. 

It  is  doubtful  whether  this  is  a  fresh-water  or  marine  form. 
Babenhorst  includes  it  among  the  former ;  the  only  gathering  in  which 
I  found  it  was  marine,  yet  containing  some  fresh  water  forms. 

Mud  from  salt  water,  coast  of  Clare,  supplied  by  Doctor  Sullivan, 
President  Queen's  College,  Cork. 

Navicula  trochtts,  (Ehr.)    Fresh  water. 

Yalve  inflated  in  the  middle,  greatly  contracted  towards  the  ends, 
which  are  slightly  capitate ;  transverse  strias  indistinct ;  longitudinal 
stnae  distinct ;  intermediate  free  space  narrow,  except  in  the  middle, 
where  it  is  expanded.     (Plate  31,  fig.  34.) 

Kiitz.  Bac,  p.  99,  T.  iii.,  fig.  59.  Ralfs,  in  Pritch.,  p.  899.— 
Navicula  foUis,  Donkin,  N.  H.  Brit.  Diat.,  p.  44,  PI.  vi.,  fig.  15. 
There  is  considerable  difficulty  as  to  the  synonymy  of  this  species. 
Donkin  considers  it  identical  with  Navicula  follis,  Ehr.,  Navicula  crux, 
Ehr.,  and  Navicula  inflata,  Kiitz.  Supposing  the  figures  of  the  last  named 
as  delineatedby  Kutzing  (Bac,  T.iii.,  fig.  36),  andby  Babenhorst  (Siissw. 
Diat.,  p.  41,  T.  v.,  fig.  10),  to  be  correct,  and  that  the  former  author 
was  correct  in  supposing  Navicula  inflata  to  be  identical  with  Navicula 
follis,  Ehr.,  I  cannot  think  that  the  latter  is  likely  to  be  identical 
with  Navicula  trochus.  Kiitzing  has  figured  Navicula  trochus  so  accu- 
rately, that  it  is  easily  recognisable ;  it  is  identical  with  that  under 
consideration,  and  also,  as  it  appears  to  me,  with  that  named  Navicula 
follis,  by  Donkin.  ^ 

Lough  Moume  deposit. 


370  Proceedings  of  the  Royal  Irish  Academy, 

NavieUla  produeta,  (Wm.  Sm.)     Freah  water. 

Valve  linear,  elliptical;  ends  produced  and  slightly  capitate; 
transverse  striae  distinct ;  linear-punctate  parallel ;  longitudinsd  striae 
distinct ;  intermediate  free  space  very  narrow ;  length  '0040,  breadth 
•0010.     (Plate  31,  fig.  35.) 

TTm.  Sm.,  B.D.,  Vol.  i.,  p.  61,  PL  xvii.,  fig.  144.  Ralfs,  in 
Pritch.,  p.  902,  PI.  vii.,  fig.  62.  Grunow,  Verhand.  der  K.  K.  Zool. 
Bot.  Gesell.,  Band  x.,  1860,  p.  643. — Navicula  afl^s,  var.  producta, 
Kab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  197. 

Botanical  Gardens  of  Trinity  College,  Dublin.  Lower  Lake,  Killar- 
ney,  Co.  Kerry.     Sub-peat  Deposit,  Dromore,  Co.  Down. 

Navicula  coccononeiformiSf  (Gregory).     Fresh  water. 

Valve  elliptical ;  transverse  striae  very  fine,  linear  slightly  radiate ; 
longitudinal  striae  more  obvious;  intermediate  free  space  narrow, 
lanceolate;  length  -0016,  breadth  -0008.     (Plate  31,  fig.  36.) 

None  of  the  authors  I  am  acquainted  with  have  alluded  to  the 
longitudinal  striae,  which  notwithstanding  are  very  obvious  when  the 
valve  is  observed  in  a  dry  state.  When  mounted  in  balsam,  they  are 
quite  undistinguishable,  except  with  very  high  powers,  and  with  good 
illumination. 

Gregory,  Q.  J.  M.  S.,  1856,  p.  6,  PI.  i.,  fig.  22.  Wm.  Sm.,  B.  D., 
Vol.  ii.,  p'.  92.  Ralfs,  in  Piitch.,  p.  896.  Grunow,  Verhand.  der 
K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  660,  T.  iv.,  fig.  9.  Bab. 
FI.  Eur.  Alg.,  sect.  1,  fig.  186  and  p.  189.  Donkin,  N.  H.  Brit.  Diat., 
p.  22,  PI.  iii.,  fig.  11.  Lagerstedt,  Siitv.  Diat.  friLn  Spetsbergen  och 
Beeren  Eiland,  p.  32,  T.  ii.,  fig.  8. 

Lough  Mask,  near  Toumakeady,  Co.  Mayo.  Lough  Moume 
deposit. 

JNavieula  Koitchyiy  (Grunow).     Fresh  water. 

Valve  small,  elliptical,  lanceolate;  ends  slightly  produced,  and 
occasionally  slightly  constricted ;  central  nodule  large  and  quadrangu- 
lar ;  striae  fine,  linear,  in  the  middle  more  distinct  than  towards  the 
ends,  radiate ;  longitudinal  striae  distinct;  length  -0013,  breadth  '0006. 
Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  638,  T.  iv.,  fig.  12.  This  author  represents  the  striae  as  moniliform, 
but  in  the  few  forms  that  came  under  my  notice  I  could  not  verify 
this  representation.  The  longitudinal  striae  are  not  noticed  by  Grunow, 
but  with  careful  manipulation  they  were  very  apparent  in  my  speci- 
mens. Grunow  gives  three  figures  of  this  species  ;  of  these  the  short- 
est and  broadest,  and  that  in  which  the  striae  are  not  so  distinct  is  the 
form  with  which  my  specimens  are  most  in  accordance. — ^Navicula 
Kotschyana,  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  193. 

Lough  Mask,  near  Tourmakondy,  Co.  Mayo. 


O'Meara — Report  an  iJ^e  Irish  JDiatomacecB.  371 

ITavicula  maxima j  (Gregory).     Marine. 

Fnistules  on  front  view  slighly  constricted  in  the  middle,  rounded 
at  the  ends ;  valve  linear,  ends  rounded ;  transverse  strise  fine,  linear, 
parallel ;  longitudinal  striae  two  or  three ;  intermediate  free  space 
narrow,  slightly  expanded  in  the  middle ;  length  about  -0050,  breadth 
about  -0011.     (PI.  31,  fig.  38.) 

Gregory,  Q.  J.  M.  S.,  1855,  p.  41,  PI.  iv.,  ^^.  10.  Ralfs,  in 
Pritch.,  p.  909,  PI.  vii.,  fig.  75.  Donkin,  N.  H.  Brit.  Biat.— The  last 
named  author  regards  this  species  as  identical  with  Navicula  bicuneata, 
Grunow.  There  is  certainly  a  strong  resemblance  between  the  two 
forms  in  many  particulars,  but  nevertheless  they  seem  to  me  perfectly 
distinct.  Navicula  bicuneata  is  much  broader,  ever  constricted,  some- 
times very  much  so,  but  one  longitudinal  sulcus  is  noticeable  in  it, 
whereas  in  Navicula  maxima  the  longitudinal  lines  are  more  nume- 
rous, and  not  so  distinctly  marked.     Eab.  El.  Eur.  Alg.,  sect,  i.,  p.  172. 

Portmamock,  Ireland's  Eye,  Co.  Dublin'.  Breaches  near  Newcas- 
tle, Co.  Wicklow.  Seaweeds,  Kilkee.  Stomachs  of  Ascidians,  Co. 
Clare. 

Var.  lineariSy  (Grunow).     Marine. 

Valve  much  narrower  and  shorter  than  the  typical  form,  trans- 
verse strue  finer ;  longitudinal  striae  obvious ;  intermediate  free  space, 
narrow,  not  expanded  in  the  middle ;  length  '0032 ;  breadth  '0005. 
(PI.  31,  fig.  39.) 

Navicula  linearis,  Grunow,  Verhand..  der  K.  K.Zool.  Bot.  Gesell., 
Band  x.,  1860,  p.  546,  T.  iii.,  fig.  2.  Eab.  Fl.  Eur.  Alg.,  sect,  i., 
p.  180. 

Stomachs  of  Ascidians,  Co.  Clare.  Stomachs  of  Ascidians,  Bound- 
stone  Bay.     Arran  Islands,  Co.  Galway. 

Far.  lata,  (O'Meara).     Marine. 

Valves  as  in  the  typical  form,  but  relatively  shorter  and  wider,  the 
ends  somewhat  cuneate ;  length  -0030  ;  breadth  '0010. 

Stomachs  of  Ascidians,  Co.  Clare. 

Navicula  suhulaj  (Kiitz.)    Marine. 

Valve  lanceolate,  transverse  striae  very  obscure,  longitudinal,  ob- 
vious ;  the  dry  valve  pale  straw-colour ;  intermediate  free  space  very 
narrow;  length  about  0024  ;  breadth  about  0004.  (PI.  31,  fig.  40.) 
Kiitz.  Bac,  p.  91,  T.  xxx.,  fig.  19.  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  548,  T.  iii.,  fig.  24.  Rab.  Fl.  Eur. 
Alg.,  sect,  i.,  p.  175.  The  specimens  I  have  met  with  are  much 
shorter  than  that  figured  by  Kiitzing,  and  agree  with  the  figure  of 
Grunow. 

Stomachs  of  Ascidians,  Co.  Clare.  Stomachs  of  Ascidians,  Round- 
stone  Bay,  Co.  Galway.     Malahide,  Co.  Dublin. 


372  Proceedings  of  the  Royal  Irish  Aeadeniy. 

Navictiln  trandueiday  N.  8.     Marine. 

Valve  lanceolate,  transverse  stris  obvious,  costate,  radiate ;  longi- 
tudinal Btriae,  two  or  three  obvious;  length,  *0020,  breadth,  '0003. 
(PL  31,  fig.  41.) 

Stomachs  of  Ascidians,  Co.  Clare. 

Navieula  papiUiferay  N.  8.     Marine. 

Yalve  elliptical-lanceolate,  ends  produced,  papilliform;  median 
line  incurved  and  expanded  towards  the  central  nodule ;  intermediate 
free  space  narrow ;  transverse  strias  obsolete,  longitudinal  striae  ob- 
vious, numerous;  length  *0020,  breadth  *0006.     (PI.  31,  fig.  42.) 

Stomachs  of  Ascidians,  Eoundstone  Bay. 

Navicula  lihumieay  (Grun.)     Marine. 

Valve  elliptical,  lanceolate,  transverse  striae  fine,  linear,  slightly 
radiate ;  longitudinal  striae  indistinct,  yet  with  good  light  noticeable  ; 
intermediate  free  space  narrow,  lanceolate.     (PI.  31,  fig.  43.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  (leseU.,  Band  x.,  1860,  p. 
547,  T.  iii.,  fig.  25.     Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  172. 

Stomachs  of  Ascidians,  Co.  Clare.  Stomachs  of  Ascidians,  Bound- 
stone  Bay.     Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Navieula  plumhicolor,  N.  S.     Marine. 

Valve  linear,  with  rounded  ends ;  length,  '0018;  breadth,  '0007; 
transverse  striae  very  obscure,  punctate,  radiate,  longitudinal  sulcus 
sub-marginal ;  longitudinal  striae  more  easily  observed  than  the  trans- 
verse ;  intermediate  free  space  narrow,  linear ;  dry  valve  of  a  leaden 
colour.     (PL  31,  fig.  44.) 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Navieula  veneta,  (Kiitz.)    Brackish  water. 

Valve  minute;  length, '0010 ;  breadth,  '0003;  lanceolate,  ends 
slightly  produced ;  transverse  striae  faint,  convergent  in  the  middle  ; 
longitudmal  striae  noticeable  with  good  illumination;  longitudinal 
fi-ee  space  narrow,  linear.     (PL  31,  fig.  45.) 

Kiitz.  Bac,  p.  95,  T.  xxx.,  fig.  76.  Bonkin  (N.  H..  Brit.  Biat., 
p.  43,'  PL  vi.,  fig.  13,)  rightly  observes  that  the  form  ''is  abun- 
dant in  estuaries  and  harbours  between  tide  marks."  Bab.  Sussw. 
Diat.,  p.  39,  T.  vi.,  fig.  83.  Ealfs,  in  Pritch.,  p.  901.  None  of  the 
above  authors  refer  to  the  longitudinal  striae,  which,  however,  by 
carefxil  illumination  may  be  easily  detected  if  the  valves  be  dry. 

Mouth  of  Bray  River,  Co.  Wicklow.  DoUymount  Strand,  Co. 
Dublin.     Galwny  Bay,  near  town  of  Galway. 


O'Meara — Bepart  on  the  Irish  Diatomaeece.  373 

Navieula  johnsonixy  CWm.  Sm.)     Marine. 

Yalve  long  and  narrow  ;  length,  *0060 ;  breath,  *0005 ;  inflated  in 
the  middle  and  at  the  ends ;  transverse  strise  very  flne,  parallel,  longi- 
tudinal striae  more  easily  detected;  colour  of  dry  valve  whitirfi. 
(PL  31,  fig.  46.) 

Pinnulartajohnsonii,  Wm.  Sm.  B.  D.,  Vol.  i.,  p.  68,  PI.  xix.,  fig. 
1 79.  Eab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  211.  Eabenhorst  considers  the  form 
identical  with  Navicula  scopulorum,  De  Brebisson.  In  this  opinion  he 
agrees  with  Ralfs,  in  Pritch.,  p.  895,  andDonkin,  N.  H.  Brit.  Diat.,  p.  73, 
PI.  xii. ,  fig.  6 .  I  cannot  find  any  figure  of  De  Brebisson's  species,  Navicula 
scopulorum,  and  consider  the  identification  of  the  last  named  with  the 
present  species  more  than  doubtful,  inasmuch  as  Kiitzing  regards  that 
form  as  identical  with  Navicula  mesotyla,  figured  by  him,  Bac,  T.  v., 
fig.  3,  and  T.  xxviii.,  fig.  84.  These  figures  are  obscure  as  to  details, 
but  from  the  size  and  outline  I  would  think  it  impossible  to  confound 
Navicula  johnsonii  with  them,  and  therefore  I  attribute  the  species  to 
Smith,  who  has  described  and  figured  it  with  unmistakable  accuracy. 
This  course  commends  itself  the  more  to  my  judgment,  inasmuch  as 
Grunow  has  described  and  figured  under  the  name  of  Kavicula  scopu- 
lorum a  form  which  is  obviously  distinct  from  that  under  considera- 
tion. 

Bannow,  Co.  Wexford.  Malahide,  Portmamock,  Co.  Dublin. 
Mouth  of  the  River  Nannywater,  Laytown,  Co.  Meath. 

Navicula  stmulaiu,  (Donkin).     Marine. 

Valve  linear,  with  long  cuneate  ends;  transverse  striae  very  faint; 
longitudinal  striae  quite  noticeable  with  good  illumination,  if  the  valve 
be  dry ;  longitudinal  free  space  narrow,  except  in  the  middle,  where 
it  spreads  out  to  the  margin  in  a  narrow  stauroform  band ;  length 
•0030,  breadth  0006.     (Plate  31,  fig.  47.) 

The  present  species  I  consider  to  be  identical  with  that  so  named 
by  Donkin,  N.  H.  Brit.  Diat.,  p.  60,  PI.  ix,  fig.  3.  Donkin  considers 
it  the  same  as  Amphiprora  constricta,  Ehr.,  but  in  this  opinion  I  can- 
not concur.  Donkin  does  not  notice  the  longitudinal  striae ;  but  in  all 
other  respects  the  present  form  is,  in  my  mind,  not  distinguishable 
from  the  species  named  Navicula  simulans  by  that  author. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway.  Malahide, 
Co.  Dublin. 

Navicula  delginensia,  N.  S.     Marine. 

Valve  rhomboid,  gradually  attenuated  towards  the  broadly  rounded 
ends ;  transverse  striae  very  faint ;  longitudinal  striae  easily  detected, 
more  especially  at  the  margin,  where  there  is  a  strongly  marked  sul- 
cus ;  intermediate  free  space  narrow,  lanceolate  towards  the  ends,  and 
slightly  expanded  in  the  middle ;  length  '0020 ;  breadth  in  the  mid- 
dle -0006.     (PI.  31,  fig.  48.) 

This  form  is  in  outline  very  similar  to  a  species  described  and 


374  Proceedings  of  the  Royal  Irish  Academy. 

fibred  by  Gninow  as  Navicula  scopnloram,  in  Verhand.  der  K.  K.  Zool. 
Bot.  Gesell.,  Band  x.,  1860,  p.  547,  T.  iii.  fig.  6.  The  present  species, 
however,  is  shorter,  broader,  and  more  rhombic ;  the  transverse  strisB 
more  obscure,  and  not  reaching  the  median  line,  but  leaving  a  distinct 
intermediate  free  space. 

Seaweeds,  Dalkey  Island,  ICalahide,  Co.  Dublin. 

(f)  Crassinerpet. 

**  Formi  far  the  moit  pari  lanceolate,  with  very  strong  median  lines 
and  very  fine  scarcely  noticeabU  structure,  in  which  the  longitudinal  stria 
come  out  mors  distinctly  than  the  transverse.  These  approach  the  group 
Zimosa,  from  which,  however,  they  differ  essentially  by  the  colorless  condi- 
tion of  the  valves  in  a  dry  state.  In  the  appearance  of  the  median  line 
there  is  an  approximation  to  some  forms  of  the  group  Cuspidatce  not  to  he 
mistaken." --Gmnow. 

Navicula  rhomhoides,  (Ehr.)    Fresh  water. 

Yalve  rhomboid;  lanceolate;  ends  slightly  rounded ;  median  line 
distinct,  with  two  longitudinal  lines  close  to  and  nearly  parallel  with 
it ;  slightly  expanded  in  the  middle,  united  towards  the  ends ;  the 
median  line  extending  slightly  beyond  the  point  of  junction ;  striae 
very  faint ;  length  about  "0045 ;  breadth  about  0009.  (Plate  31,  fig.  49.) 

With  a  high  objective  and  very  skilful  illumination  the  stris  are 
found  to  be  parallel.  It  is  noteworthy  that  in  a  gathering  made  by 
me  at  Lough  Awn,  on  the  summit  of  the  Slieveaneiran  Mountain,  this 
form  occurred  in  abundance,  for  the  most  part  free,  but  frequently  in 
mucous  tubes,  ever  in  single  files,  and  in  some  cases  the  frustules  were 
placed  end  to  end,  without  any  mucous  investment. 

Kiitz.  Bac.,  p.  94,  T.  xx\iii.,  fig.  45 ;  and  T.  xxx.,  fig.  44.  This 
author  attributes  the  species  to  Ehrenberg.  Wm.  Sm.,  B.  D.,  vol.  i., 
p.  46,  PI.  xvi.,  fig.  129.  Rab.  Sussw.  Diat.,  p.  38 ;  T.  v.,  fig.  13.  This 
figure  represents  the  form  as  much  smaller  than  it  is  generally  found 
to  be.  Ilalfs,  in  Pritch.,  p.  903 ;  Grunow,  Verhand.  der  K.  K.  Zool. 
Bot.  Gesell,  Band  x.,  1860,  p.  549.  Donkin,  K  H.  Brit.  Diat.,  p.  42, 
PI.  vi.,  fig;  11.     Schumann,  Die  Diat.  der  Hohen  Tatra.,  p.  68. 

Pool,  Glencar,  near  Glengariff,  Bantry,  Co.  Cork.  Lower  Lake, 
KiUamey,  Arraglen,  near  Castlegrcgory,  Co.  Kerry.  Friarstown, 
Piperstown,  Co.  Dublin.  River  Bann,  near  Coleraine,  Co.  Deny.  Con- 
nemara,  Co.  Gal  way.  Rathdrum,  Glenchrce,  Co.  Wicklow.  Deposit, 
ToUymore  Park,  Co.  Down. 

Navicula  serians,  (De  Breb.)     Freshwater. 

Yalve  elliptical-lanceolate ;  ends  slightly  rounded ;  median  line  dis- 
tinct, as  are  adso  the  two  longitudinal  lines,  close  to  and  parallel  to  the 


O'Meara — Report  on  the  Iri^h  DiatomacecB.  375 

Bame ;  transverse  striae  obscttre,  slightly  oblique ;  longitudinal  striae  dis- 
tinct; length  about  -0038  ;  breadth  about  -0009.  (Plate  31,  fig.  50.) 
Kiitz.  Bac.,  p.  92;  T.  xxx.,  fig.  23;  T.  xxviii.,  fig.  43.  This 
author  considers  the  species  identical  with  Erustulia  serians,  De  Brebis- 
son,  and  with  Navicula  lineolata,  Ehr.  He  adds,  "  I  hare  no  doubt 
that  the  Ehrenbergian  form,  which  has  been  described  in  our  T.  xxviii., 
^^,  43,  according  to  Ehrenberg,  is  perfectly  identical  with  that  of  De 
Brebisson.''  That  form  is  rather  smaller  than  ^avicula  serians,  and 
therefore  some  doubt  may  reasonably  be  entertained  on  the  subiect. 
It  seems  better  then,  with  Donkin,  to  attribute  the  species  to  De  Brd- 
bisson  than  to  abandon  the  specific  name  by  which  the  species  has  been 
so  long  known.  .  Wm.  Sm.,  B.  D.,  vol.  i.,  p.  47,  PI.  16,  fig.  130. 
Eab.  Sussw.  Diat.,  p.  38 ;  T.  vi.,  fig.  51 ;  Ralfs,  in  Pritch.,  p.  904. 
Grunow,  Yerhand.  der  K.  K.  Zool.  Bot.  Gesell,  Bandx.,  1860,  p.  549  ; 
T.  v.,  fig.  13.  Cleve,  Cm  Svenska  och  Norska  Diat.,  p.  228.  Don- 
kin,  N.  H.  Brit.  Diat.,  p.  41,  PL  vi.,  fig.  10. 

Pool,  Cushendun,  Co.  Antrim.  Piperstown,  Co.  Dublin.  Glen- 
chree,  Co.  Wicklow.  Pool  near  town  of  Wicklow.  Tollymore  Park 
deposit,  Co.  Down. 

Navieula  cramn&rvia,  (De  Br^b.)    Fresh  water. 

Yalve  small,  elliptical-lanceolate  ;  ends  produced  and  slightly  con- 
stricted ;  longitudinal  sulci  parallel  to  the  median  line,  distinct ;  striae 
obsolete;  length  about  '0024 ;  breadth  about  -0005.  (Plate  31,  fig.  51.) 

Wm.  Sm.,  B.D.,  Vol.  i.,  p.  47,  Supp.  PI.  xxxi.,  fig.  271,  who 
describes  and  figures  the  species  according  to  specimens  furnished  by 
DeBr^bisson.  Ralfs,  in  Pritch.,  p.  900.  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  548,  T.  v.,  fig.  12.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  228.  Donkin,  N.  H.  Brit.  Diat.,  p.  42, 
PI.  vi.,  fig.  12.  This  last  named  author  considers  this  species  identical 
with  Frustulia  saxonica,  Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  227. 

Friarstown,  Piperstown,  Featherbed  Mountain,  Co.  Dublin.  Lough 
Gill,  Co.  Kerry.  Bantry,  Co.  Cork.  Eostrevor,  Co.  Down.  Ratti- 
drum^  Glencree,  Co.  Wicklow. 

Na/oieula  dirhynohuij  (Ehr.)    Fresh  water. 

Valve  nearly  linear,  narrow ;  ends  produced,  and  slightly  capitate. 
Longitudinal  sulci  parallel  with  median  line,  distinct.  Transverse 
striae  obsolete;  longitudinal  striss  distinct;  length,  '0022,  breadth, 
•0005.     (Plate  31,  fig.  52.) 

Kiitzing,  Bac,  p.  95,  T.  xxviii.,  fig.  48,  by  whom  the  species  is 
attributed  to  Ehrenberg.  Rab.  Siissw.  Diat.,  p.  40,  T.  vi.,  fig.  48. 
Ralfs,  in  Pritch.,  p.  901.  Donkin,  N.  H.  Brit.  Diat.,  p.  29,  PI.  v.', 
fig.  3.  The  last  named  author  remarks  that  '^  in  outline  this  species 
has  a  strong  resemblance  to  Navicula  affinis,  but  it  is  much  smaller. 


376  ProceedtNgt  of  the  Boj/al  Irish  Academy. 

and  distinguish od  by  the  apparent  absence  of  striae."  If  the  yalre  be 
examined  in  a  dry  state,  the  longitudinal  striae  are  distinct,  but  much 
less  numerous  and  distinct  than  in  Navicula  affinis;  the  margin 
also,  instead  of  being  perfectly  linear  as  it  is  in  the  last  named  species, 
is  slightly  elliptical. 

Lough  Mask,  near  Tourmakeady,  Co.  Mayo.  Featherbed  Moun- 
tain, Co.  Dublin. 

Na/viada  roitellufn,  (Wm.  8m.)    Fresh  water. 

Valves  broadly  elliptical ;  ends  produced  into  very  short  narrow 
apices;  longitudinal  sulci  parallel  to  median  line  distinct;  tftria 
obscure;  length  '0020;  breadth  -0010.     (Plate  31,  fig.  53.) 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  93.  Ralfs,  in  Pritch.,  p.  900.  Ghru- 
wm,  Verhand.  der  K.  E.  Zool.  Bot.  GeselL,  Band  x.,  1860,  p.  550, 
T.  iy.,  fig.  10.  This  form,  as  described  by  Grunow,  is  narrower,  and 
the  apices  much  wider  than  in  my  specimens ;  the  transverse  striae  as 
described,  are  very  fine  and  parallel,  but  as  my  specimens  were  mounted 
in  balsam,  I  could  not  detect  the  striae.  Donkin,  N.  H.  Brit.  Diat., 
p.  40,  PL  vi.,  fig.  7.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  195.  The  last 
named  author  describes  the  striae  as  very  delicate  and  parallel. — ^Navi- 
cula  apiculata,  Gregory  Q.  J.  M.  S.,  Vol.  iv.,  1856,  PI.  i.,  fig.  13,  who 
attributes  the  form  to  Wm.  Smith. 

Killakee,  Co.  Dublin. 

Navitula  lavmima,  (Eiitz.)     Fresh  water. 

Valve  colourless,  slightly  expanded  in  middle,  slightly  constricted 
towards  the  broad  rounded  ends;  median  line  strongly  developed; 
transverse  striae  very  fine,  slightly  radiate ;  longitudinal  striae  distinct ; 
intermediate  free  space  narrow,  except  in  the  middle,  where  some- 
times it  seems  to  expand  in  a  short  narrow  stauroform  band ;  at  the 
extreme  end  a  distinct  transverse  line  is  noticeable  at  right  angles 
with  the  median  line ;  length  0015,  breadth  0004.    (Plate  31,  fig.  54.) 

Kutz.  Bac.  p.  96,  T.  xxi.,  fig.  14.  Wm.  Sm.,  B.  D.,  Vol.  ii., 
p.  91.  Grunow,  Verhand.  der  E.  E.,  Zool.  Bot.  Gesell.,  Band  x., 
1860,  p.  549,  T.  iv.,  fig.  5.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  188. 
Donkin,  N.  H.  Brit.  Diat.,  p.  28,  PL  v.,  fig.  2. 

Lower  Lake,  Eillamey,  Co.  Eerry.  Derrylane  Lough,  Co.  Cavan. 
Lough  Neagh,  near  Antrim  town.  Ulster  Canal,  near  Poyntzpass, 
Co.  Armagh.  Loughbrickland  Lake,  Co.  Down.  River  Bann,  near 
Coleraine,  Co.  Derry.  Trinity  College  Botanic  Gardens,  Co.  Dublin. 
Eilleshin,  Queen's  Co.     Feighcullen,  Co.  Eildare. 

Navicula  ohhngeUa,  (Naegeli  ?)    Fresh  water. 
Valve  small,  linear,  elliptical;  ends  rounded;   longitudinal  sulci 
close  to  median  line,  strongly  developed,  parallel;  transverse  strias 


O'Meara — Meport  an  the  Iriah  Diatoniacew.  377 

fine,  but  easily  detected,  parallel ;  longitudinal  strise  generally  obscure; 
intermediate  free  space  narrow,  except  in  the  middle,  where  it  expands 
into  a  quadrangular  area ;  length  about  '0008,  breadth  about  '0008. 
(Plate  31,  fig.  55.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell,  Band  x.,  1860, 
T.  iv.,  fig.  4.  Grunow,  with  a  note  of  doubtfulness,  refers  the  species 
to  Naegeli.  Schumann,  Die  Diat.  der  Hohen  Tatra,  p.  70.  Rab.  Fl. 
Eur.  Alg.,  sect.  1,  p.  185. 

Lough  Berg,  Co.  Galway.  Killakee,  Co.  Dublin.  Ditch  near 
town  of  Galway. 

NavictUa  tncurva,  (Greg.)     Fresh  water. 

Valve  slightly  incurved  in  the  middle  ;  ends  broadly  produced,  sub- 
capitate  ;  longitudinal  sulci  parallel,  with  mediaA  line  distinct ;  stria) 
obscure;  length  about  -0020,  breadth  -0005.     (Plate  31,  fig.  56.) 

Gregory,  Q.  J.M.  8.  1856,  p.  8,  PI.  i.,  fig.  26.  Ralfs,  in  Pritch., 
p.  893.  Rab.  FL  Eur.  Alg.,  sect,  i.,  p.  203.  Donkin,  N.  H.  Brit. 
Diat.,  p.  38,  PL  vi.,  fig.  2. 

Portmamock,  Co.  Dublin.     Callows,  near  BaUinasloe,  Co.  Galvay. 

(g)    Monilifera. 

Vdhea  more  or  less  lanceolate;  stria  obviomly  moniUform,  not  reach- 
ing  the  median  line  ;  free  intermediate  space  narrow,  except  in  the  middle, 
where  it  is  generally  more  or  less  expanded, 

Navietda  puncttdata,  (Wm.  Smith.)     Brackish  or  marine. 

Valve  broadly  elliptical,  with  alightly  apiculate  ends ;  intermediate 
free  space  narrow,  slightly  expanded  in  the  middle;  stri®  close,  radiate ; 
length  about  '0026,  breadth  -0012.     (Plate  32,  fig.  1.) 

Wm.  8m.,  B.D.,  vol.  L,  p.  52,  PL  xvi.,  fig.  151.  Grunow,  Verhand. 
der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  537. — Navicula  marina, 
Ralfs,  in  Pritch.,  p.  903.  Rab.  FL  Eur.  Alg.,  sect,  i.,  p.  202.  Donkin, 
N.  H.  Brit.  Diat.,  p.  19,  PL  iii.,  fig.  5.  The  last  named  author 
remarks,  ''Although  this  species  is  described  as  marine  in  the  Synop- 
sis of  Prof.  Smith,  I  have  never  found  it  in  purely  marine  localities, 
where  its  congener  N.  granulata  is  found."  Some  of  the  undernamed 
localities  in  which  I  have  found  the  species  are  decidedly  marine. 

Stomachs  of  Ascidians,  Belfast  Lough,  Co.  Antrim.  Seaweeds, 
Bannow,  Co.  Wexford.  Portmamock,  Co.  Dublin.  Rostrevor,  Co. 
Down.  Seaweeds,  Kilkee,  Co.  Clare.  Laytown,  Co.  Meath.  Dre- 
hednamaud,  near  Castiegregory,  Co.  Kerry. 

Naoieula  granuUtta,  (De  Br^bisson).     Marine. 
Valve  broadly  elliptical,  with  slightiy  produced  broad  rounded 
ends;  intermediate  free  space    narrow,  linear,  except  at  the  cen- 


378  Proceedings  of  the  Royal  Irish  Academy, 

tre,  where  it  expands  considerably  ;  expanded  area  somewhat  rounded ; 
striaB  monilif omiy  convorgcnt  in  the  middle,  then  strongly  radiate ; 
length  0035  ;  breadth  0017.     (Plate  32,  fig.  2.) 

Donkin,  Q.  J.  M.  S.,  1858,  p.  17,  PI.  iii.,  fig.  19,  who  attributes 
the  species  to  Be  Br^bisson.  Rails,  in  Pritch.,  p.  903.  Cleve,  Om 
Bvenska  och  Norska  Diat.,  p.  226.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p. 
201.     Donkin,  N.  H.  Brit.  Diat.,  p.  17,  PI.  iii.,  fig.  1. 

Drehednamaud,  near  Castlegregory,  Co.  Kerry.  Stomachs  of  Aa- 
eidians,  Roundstone  Bay,  Stomachs  of  Ascidians,  Broadhayen  Bay, 
Galway  Bay,  Co.  Galway, 

Navictda  humero$ay  (De  Br^bisson.)     Marine. 

Valve  linear,  elliptical,  gradually  contracted  towards  the  broad,  pro- 
duced, rounded  ends ;  slightly  constricted  in  the  middle ;  striae  close, 
moniliform;  puncta  small,  convergent  in  the  middle,  radiate  towards 
the  ends ;  intermediate  free  space  narrow,  except  ia  the  middle,  where 
it  is  broadly  and  somewhat  roundly  expanded ;  length,  about  -0032, 
breadth,  about  0013,  and  in  middle  about  -9012.     (Plate  32,  fig.  3.) 

Wm.  Smith,  (B.  D.,  Yol.  ii.,  p.  93),  who  attributes  the  species  to 
De  Brebisson.  Ralfs,  ia  Pritch.,  p.  903.  Rab.  Fl.  Eur.  Alg.,  sect,  i., 
p.  201. 

Bannow,  River  Slaney,  near  Killurin.  Co.  Wexford.  Portmar- 
nock,  Malahide,  Co.  Dublin.  Seaweeds,  Portrush,  Co.  Antrim. 
Caum  Lough,  near  Tralee,  Lough  Gill,  Co.  Kerry.  Kilkee,  Co. 
Clare.     Salt  marsh,  Kilcool,  Co.  Wicklow. 

Var.fiucaiay  (Schumann).     Marine. 

Like  the  typical  form,  but  having  the  ends  slightly  capitate,  and 
the  margins  perfectly  linear;  length  *0038,  breadthr0014.  (Plate  32, 
fig.  4.) 

Likely  the  same  as  Navicula  fuscata,  Schumann,  Die  Preussische 
Diat.,  p.  57,  T.  ii.,  fig.  43. 

Drehidnamaud,  near  Castlegregory :  Lough  Gill,-  Co.  Kerry. 
Stomachs  of  Ascidians,  Roundstone  Bay,  Co.  Galway. 

*Var.  qtiadrataj  (Gregory).    Marine. 

Like  the  typical  form,  but  much  shorter  and  relatively  broader ; 
the  margins  linear ;  the  ends,  too,  being  broader  and  less  produced ; 
length  -0020,  breadth  -0012.     (Plate  32,  fig.  5.) 

Navicula  quadrata,  Gregory,  Q.  J.  M.  S.,  1856,  p.  41,  PL  v.,  fig.  5. 
Donkin  (N.H.Brit. Diat.,  p.  18)  considers  this  identical  with  Navicula 
humerosa,  and  Ralfs  adopts  the  same  opinion  in  Pritchard,  p.  903. 

Lough  Gill,  Co.  Kerry.  Stomachs  of  Ascidians,  Broadhaven  Bay, 
Co.  Ghdway.    Seaweeds,  Portrush,  Co.  Antrim. 


O'Meara — Report  on  the  Irish  Diatomacece.  379 

Navicula  latiMima^  (Gregory).     Marine. 

Valve  large,  broadly  elliptical ;  ends  slightly  produced,  rounded ; 
intermediate  free  space  broad,  lanceolate,  greatly  expanded  around  the 
central  nodule ;  striae  linear,  with  moniliform  striae  interposed,  conver- 
gent in  the  middle,  radiate  towards  the  ends ;  length  '0060,  breadth 
•0032.     (Plate  32,  fig.  6.) 

Gregory,  Q.J.  M.  8.,  1856,  p.  40,  PI.  v.,  fig.  4.  Rails,  in  Pritch., 
p:  903,  PI.  vii.,  fig.  70.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  201.  Donkin, 
N.  H.  Brit.  Biat.,  p.  17,  PI.  iii.,  fig.  2. — Pinnularia  divaricata, 
O'Meara,  Q.  J.  M.  8.,  1867,  p.  116,  PL  v.,  fig.  7. 

Arran  Islands,  Stomachs  of  Ascidians,  Eoundstone  Bay,  Co. 
Galway. 

Navicula  meniscus j  (Schumann).     Presh  water. 

Valve  broadly  elliptical;  ends  slightly  produced,  not  capitate; 
intermediate  free  space  narrow,  except  in  the  middle,  where  it 
expands  into  a  large  stauroform  band,  wider  towards  the  margin  than 
at  the  central  nodule ;  strisB  linear,  with  moniliform  striae  interposed, 
convergent  in  the  middle,  radiate  towards  the  ends ;  length  '0026, 
breadth  -0013.     (Plate  32,  fig.  7.) 

Schumann,  Die  Preussbche  Diat.,  p.  55,  T.  ii.,  fig.  32.  Schumann's 
account  of  the  locality  in  which  the  form  was  found  by  him  leaves 
some  doubt  as  to  whether  the  deposit  in  which  the  form  was  discovered 
was  marine  or  fresh  water;  his  words  are:  **In  deposito  Eegimon- 
tano,  in  portu  Pillawensi,  in  Mari  Baltico.  Xagerstedt,  however,  in- 
cludes the  form  among  fresh- water  species,  under  the  name  of  I^avi- 
cula  punctata,  var.  asymmetrica,  Sotvat.  Diat.  fran  Spetsbergen,  p.  29, 
T.  ii.,  fig.  7."  This  figure  so  precisely  corresponds  in  all  respects  with 
the  form  here  described,  as  to  render  the  identity  perfectly  certain. 
Lagcrstedt  states  that  the  frustule  on  front  view  is  slightly  unsymme- 
tncal  on  the  longitudinal  axis.  This  seems  to  me  to  have  been  acci- 
dental, arising  perhaps  from  the  valves  having  been  separated  at  one 
end  while  adhering  at  the  other;  he  adds,  '^ only  a  single  specimen  of 
this  variety  was  found."  And  I  have  precisely  the  same  report  to 
make.  So  distinct  is  this  form  in  its  leading  characters  that  I  consider 
it  a  perfectly  independent  species,  and  not  to  be  regarded  as  a  variety 
of  Kavicula  punctata. 

Pond  near  the  city  of  Armagh. 

Navicula  lucida,  "N.  8.     Marine. 

Valve  broadly  elliptical,  with  sub-lanceolate  ends;  intermediate 
free  space  lanceolate,  narrow,  except  in  the  middle,  where  it  expands 
considerably;  a  strongly  marked  submarginal  sulcus  is  present; 
striae  moniliform ;  puncta  very  close ;  convergent  in  the  middle ; 
divergently  radiate  towards  the  apices  ;  length  -0020  ;  breadth  •0012» 
(Plate  32,  fig.  8.) 

Stomachs  of  Ascidians,  Eoundstone  Bay,  Co.  Galway. 

».  I.  A.  PROC,  «BR.  n.,  VOL.  II.,  SCIEHOB.  2  T 


380  Proceedings  of  the  Boyal  Irish  Academy. 

Navictda  cluthmsis,  (Gregory).    Karinc. 

Valve  broad Iv  elliptical,  with  rounded  ends;  'intermediate  free 
space  narrow,  linear,  but  slightly  expanded  at  the  cenh^l  nodule ; 
stria)  monilifoim ;  puncta  small,  close,  nearly  parallel  in  the  middle, 
and  diverp:cntly  radiate  towaixls  the  ends;  length,  *0020;  breadth, 
•0013.     (Plate  32,  lip:.  9.) 

Gregory,  Diat.  of  Clvde,  p.  478,  PI.  ix.,  fig.  2.  Haifa,  in  Pritch., 
p.  909,  PI.  vii.,  fL^,  73.  Kab.  Fi.  Eur.  Alg.,  p.  184.— 2^avicuia 
erythraca,  Grunow,  Verlmnd.  der  K.  K.  Zool.  Bot.  Gescil.,  Band  x., 
1860,  p.  539,  T.  v.,  fig.  17. 

River  Slaney,  near  Xillurin,  Co.  Wexford.  Stomachs  of  Ascidians, 
Roundstone  Bay,  Co.  Gal  way. 

Var.  productdy  (O'Meara).     Marine. 

Pn^cisely  as  the  typical  species,  but  having  the  ends  slightly  pro- 
duced; length  0025, 'breadth  -0011.     (Plate  32,  fig.  9a.) 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Kavi'cula  punctata,  (KUtz.)     Fresh  water. 

Valve  elliptical,  ends  produced,  naiTow,  capitate;  intermediate 
free  space  narrow,  except  in  middle,  where  it  expands  into  a 
tolerably  broad  stauroform  band,  widening  towaixls  the  outer  end ; 
striae  moniliform;  puncta  small;  radiate;  length  '0032,  breadth 
•0010.     (Plate  32,  fig.  10.) 

Donkin,  N.  H.  Brit.  Diat.,  p.  36,  PI.  v.,  ^g.  12.  Lagerstedt, 
Sotvat.  Diat.  fHin  Spetsberger  och  Bceren  Eiland,  p.  29. — Stauroneis 
punctata,  Kiitz.,  Bac,  p.  100,  T.  xxi.,  ^g.  9.  Wm.  Sm.,  B.  D., 
Vol.  i.,  p.  61,  PI.  xix.,  fig.  189.  Ilalfs,  in  Pritch.,  p.  912.  Gininow, 
Verhand.  dcr  K.  K.  Zool.  Bot.  Gesell.,  Bandx.,  1860,  p.  565.  Castra- 
cane,  Catalogo  di  Diat.  raccolte  nella  Val  Intrasca,  p.  11.  Cleve, 
Cm  Svcnska  och  Korska  Diat.,  p.  228.  Rab.  Fl.  Eur.,  Alg.,  sect, 
i.,  p.  2 15. — Stauroptcra  punctata,  Rab.  Siissw.  Diat.,  p.  50,  T.  ix., 
fig.  11. 

River  Slaney,  near  Killurin,  Co.  AVexford.  Drumoughty  Lough, 
near  Kcnmare,  Lower  Lake,  Killarncy,  Lough  Gill,  Co.  Keny. 
Lough  Mask,  near  Tourmakeady,  Co.  Mayo.  Lough  Mourne  deposit, 
Co.  Antrim. 

Kavicula  lacustns,  (Gregoiy).     Fresh  water. 

Similar  to  Navicula  punctata,  but  the  striaj  are  very  much  finer ; 
and  the  intermediate  free  space  expanded  roundly,  instead  of  in  a 
staurofonn  band ;  length  about  -0020,  breadth  -0006.  (Plate  32,  fig.  1 1.) 

Gregory,  (Q.  J.  M.  S.,  1856,  p.  6,  PI.  i.,  fig.  23.)  describes 
two  distinct  varieties,  one  elliptical,  the  other  with  linear  margin 
and  produced  ends.     He  also  refers  to  an  intermediate  form,  which 


O'Meara — Report  on  the  Irish  Diatomaccce,  381 

latter,  I  presume,  to  be  the  present  one.  Balfs,  (in  Pritcli.,  p.  903), 
says  the  only  species  with  which  this  could  be  confounded  is 
Nayicula  firma,  but  it  appears  to  me  that  it  is  more  likely  to  bo 
confounded  with  Nayicula  punctata.  Eab.  Fl.  Eur.  Alg.,  sect,  i., 
p.  200. 

Lough  Mask,  near  Tourmakeady,  Co.  Mayo.  Lough  Neagh,  near 
the  town  of  Antrim.  Lough  Gill,  Lower  Lake,  KiUamey,  Pedlass 
Lake,  near  Dingle,  Co.  Kerry. 

Nmictila  maeuloga,  (Donkin).     Marine. 

Yalye  linear,  elliptical;  ends  slightly  produced  and  somewhat 
cuneate;  intermediate  free  space  linear,  narrow,  slightly  expanded 
around  the  central  nodule ;  strise  distinctly  moniliform,  parallel  in 
the  middle,  emd  divergently  radiate  towards  the  ends ;  length  *0027, 
breadth  0008.     (Plate  32,  ^g,  12.) 

Donkin,  N.  H.  Brit.  Diat.,  p.  25,  PI.  v.,  fig.  1. 

Piles  of  wooden  bridge,  DoUymount  Strand,  Co.  Dublin. 

Kavieula  tcuteHoideSf  (Wm.  Sm.)    Fresh  water. 

Valve  nearly  orbicular,  minute ;  intermediate  free  space  narrow, 
linear,  slightly  expanded  in  the  middle;  strise  distant,  moniliform, 
divergently  radiate ;  length,  -0009 ;  breadth,  -0008.    (Plate  32,  fig.  13.) 

Wm.  Sm.,  B.  D.,  Vol.  ii.,  p.  91.  Grunow,  (Verhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  533,  T.  v.,  fig.  15),  places  it  in 
intimate  connexion  with  Navicula  lyra  and  Navicula  hennedyi,  but  the 
position  I  assign  to  it  seems  to  me  more  appropriate.  Bafls,  in  Pritch., 
p.  909.     Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  185. 

Lough  Neagh,  near  Antrim.  Lough  Mask,  near  Tourmakeady, 
Co  Mayo.- 

Navicula  pusiUa,  (Wm.  Sm.)     Brackish  water. 

Valve  small,  broadly  elliptical,  ends  produced ;  narrow,  rounded; 
intermediate  free  space  narrow,  linear,  expanded  in  the  middle ;  striie 
distinctly  moniliform ;  convergent  in  the  middle,  and  radiate  towards 
the  ends ;  more  distant  in  the  middle,  closer  towards  the  ends  ; 
length  -0015;  breadth,  -0008.     (Plate  32,  fig.  14.) 

Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  52,  PI.  xvii.,  fig.  145.  Haifa,  in 
Pritch.,  p.  900.  Cleve,  Om  Svenska  och  Norska  Diat.,  p.  227.  It  is 
likely  that  the  form  mentioned  by  Cleve  may  be  a  distinct  species,  as 
he  attributes  it  to  fresh  water.  Rab.  Fl.  Eur.  sect,  i.,  p.  193. 
Donkin,  N.  II.  Brit.  Diat.,  p.  20,  PI.  iii.,  fig.  6. — Navicula  tumida, 
var.  subsalsa,  Grunow,  Verhand.  dcr  K.  K.  Zool.  Bot.  Gesell.,  Band 
X.,  1860,  p.  537,  T.  iv.,  fig.  43. 

Brackish  ditch  near  town  of  Wexford ;  Tacumshane,  Co.  Wexford. 
Ballysodaro,   Co.   Sligo.      Breaches  near   Newcastle,   Co.   Wicklow. 

2T2 


382  Proceedings  of  the  Royal  Irish  Academy. 

Lough  Gill,  Co.  Keny,  Kiyer  Bann,  near  Coleraine ;  Bellarena,  Co. 
Deny.  BrackiBh  ditches  near  town  of  Galway.  Portmamock,  Co. 
Dublin. 

Var.  lanceolata^  (Gninow).     Marino  or  brackiRh  water. 

Yalve  lanceolate,  ends  produced ;  relatively  longer  and  narrower 
than  the  typical  species.     length  *0024,  breadth  '0008. 

Nayicula  tumida,  var.  lanceolata,  Ghunow,  Yerhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  637,  T.  iv.  fig.  44.  This  as  well 
as  the  preceding  species,  being  both  incidental  to  marine  or  brackish 
water,  can  scarcely  be  regarded  as  varieties  of  Navicula  tumida,  which 
is  a  fresh  water  species. 

Portmamock,  Co.  Dublin.   Breaches  near  Newcastle,  Co.  "Wicklow. 

Navietda  tumidly  (Wm.  Sm.)     Fresh  water. 

Valve  small,  elliptical,  with  short  capitate  ends;  intermediate  free 
space  narrow,  slightly  expanded  in  the  middle ;  stri®  close,  monili- 
form;  convergent  in  the  middle,  and  radiate  towards  tho  ends; 
length  varying  from  0013  to  -0020  ;  breadth  from  0005  to  -0008. 

Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  63,  PI.  xvii.,  fig.  146.  Gninow, 
Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  637,  T.  iv., 
fig.  43a.  Cleve,  Cm  Svenska  och  Norska  Diat.,  p.  226. — Xavicnla 
Anglica,  Ralfs,  in  Pritch.,  p.  900.  Bab.  Fl.  Eur.  Alg.,  sect,  i., 
p.  193.     Donkin,  N.  n.  Brit.  Diat,  p.  36,  PI.  v.,  fig.  11^. 

Kilcool ;  streamlet  in  Powcrscourt  demesne,  Co.  "Wicklow.  Lough 
Mask,  Tourmakeady,  Co.  Mayo.     Ditch  near  town  of  Sligo. 

Var,  linearis y  (O'Meara).     Fresh  water. 

Similar  to  the  typical  form,  but  sides  linear,  ends  slightly  pro- 
duced; striae  coarser,  obviously  moniliform,  radiate;  length  -0011, 
breadth  -0005.     (Plate  32,  fig.  15.) 

Lough  Gill,  Co.  Kerry.     Lough  Mask,  Tourmakeady,  Co.  Mayo. 

ITavicula  pulchra,  (Gregory).     Marine. 

Valve  lanceolate  ;  intermediate  free  space  narrow,  expanded  in  tho 
middle;  striae  distinctly  moniliform,  racHate;  length  -0027,  breadth 
•0008.     (Plate  32,  fig.  16.) 

Gregory,  Q.  J.  M.  S.,  1856,  Trans.,  p.  42,  PI.  v.,  fig.  7.  Balfs,  in 
Pritch.,  p.  906.     Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  176. 

Galway  Bay  near  the  town  of  Galway. 


O'Meara — Report  on  the  IrUh  Diatomacea.  383 


(h)  Fuscata. 

Valves  mors  or  less  elliptical ;  stria  divided  into  ttco  portions  on  each 
^ide  of  the  nvedian  line,  hy  two  longitudinal  sulci,  forming  a  tolerably 
hroad  rhomhoidal  space  about  the  median  line. 

Navicula  fusca,  (Gregory).     Marine. 

Valve  oblong  elliptical ;  strise  obvionsly  moniliform,  radiate ;  inter- 
mediate space  lanceolate,  divided  into  three  compartments,  one  unstri- 
ate,  and  having  the  median  line  in  the  centre,  and  one  on  either  side 
striate;  centnd  nodule  large;  length  about  -0047,  breadth  about 
•0022.     (Plate  32,  fig.  17.) 

Ralfs,  in  Pritch.,  p.  898;  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  179. 
Donkin,  N.  H.  Brit.  Diat.,  p.  7,  PL  i.,  fig.  5. — Navicula  Smithii  var. 
fusca,  Gregory,  Diat.  of  Clyde,  p.  486,  PI.  ix.,  fig.  15.  Schmidt's 
Atlas  der  Diat.,  T.  vii.,  fig.  1. 

Arran  Islands ;  stomachs  of  Ascidians,  Boundstone  Bay ;  stomachs 
of  Ascidians,  Broadhaven,  Co.  Galway.    Bostrevor,  Co.  Down. 

NavicuJa  smithii,  (De  Breb.)    Marine. 

Valve  broadly  elliptical ;  striae  moniliform,  slightly  radiate ;  inter- 
mediate space  narrow,  lanceolate,  consisting  of  three  distinct  por- 
tions, one  unstiiate  about  the  median  line,  and  one  on  either  side  of  the 
latter  striate;  length  about  -0027,  breadth  about  -0012.  (Plate  32, 
fig.  18.) 

Wm.  8m.,  B.  D.,  Vol.  ii.,  p,  92.  Smith  assents  to  the  suggestion  of 
DeBr^bisson,  to  change  to  Navicula  smithii  the  form  he  had  previously 
named  Navicula  elliptica,  B.  D.,  Vol.i.,  p.  48,  PI.  xvii.,  fig.  152.  For  this 
reason  Grunow,  Heiberg,  and  Donkin  rightly  attribute  the  species  to 
De  Br^bisson.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  GeselL,  Band 
X.,  1860,  p.  531.  Heiberg,  De  Danske  Diat.,  p.  81.  Ealfs,  in 
Pritch.,  p.  898.  Rab.  PL  Eur.  Alg.,  sect,  i.,  p.  178.  Donkin,  K  H. 
Brit.  Diat.,  p.  6,  PL  i.,  fig.  4.  Schmidt's  Atlas  der  Diat.,  T.  vii., 
fig.  16. 

Arran  Islands;  Stomachs  of  Ascidians,  Boundstone  Bay;  Sto- 
machs of  Ascidians,  Broadhaven  Bay,  Co.  Galway.  Bostrevor,  Dun- 
drum  Bay,  Co,  Down.  Bannow,  Co.  Wexford.  Seaweeds,  Kilcool, 
Co.  Wicklow. 

Var.  subrotunda,  (O'Meara).     Marine. 

Like  the  typical  species,  but  nearly  orbicular. 

Schmidt's  Atlas  der  Diat.,  T.  vii.,  fig.  17,  fig.  22? 

Stomachs  of  Ascidians,  Boundstone  Bay ;  Arran  Islands,  Co.  Gal- 
way. 


384  Proceedings  of  the  Royal  Irish  Academy, 

Var'rhomliea^  (0*Meara).    Marine. 

YalvG  like  that  of  the  typical  form  in  ^neral  structure,  but  dif- 
fering in  its  distinctly  rhombic  outlinci  as  well  as  in  the  rhombic  form 
of  the  inner  band  of  strias. 

A  form  which  seems  to  me  to  be  identical  with  this  is  described  by 
Schmidt,  Atlas  der  Diat.,  T.  vii.,  fig.  18. 

Arran  Islands,  Co.  Galwaj. 

Navieula  eoUisiana,  N.  8.  Marine. 

Valve  broadly  elliptical.  Nearly  linear  at  the  margin,  with  broadly 
rounded  ends.  Intermediate  space  wide,  oblong,  elliptical.  Stria;  cos-^ 
tate.  Marginal  striate  band  wide,  striae  distinctly  moniliform,  nearly 
parallel  in  the  middle;  more  and  more  radiate  towards  the  ends; 
length  -0026,  breadth  -0016.     (Plate  32,  fig.  19.) 

This  form  is  distinguished  from  Navicula  fusca,  and  Navicula 
smithii,  which  in  other  respects  it  strongly  resembles,  by  the  broad 
oblong  elliptical  outline  of  the  inner  striate  band,  and  more  specially 
by  the  fact  that  the  strise  in  this  portion  of  the  valre  are  distinctly 
costate,  while  in  the  others  they  are  moniliform.  It  was  first  ex* 
hibited  by  me  at  a  meeting  of  the  Dublin  Microscopical  Club,  somo 
years  since,  at  the  house  of  the  late  Surgeon  Maurice  Collis. 

Stomachs  of  Ascidians,  Boundstone  Bay,  Arran  Islands,  Co^ 
Oalway.     Kilcool,  Co.  Wicklow. 

Navicula  <Mtiva,  (Donkin).     Marine. 

Valve  linear,  elliptical ;  striae  fine,  obscurely  moniliform,  parallel  in 
the  middle,  slightly  radiate  towards  the  ends;  inner  striate  band  narrow^ 
elliptical ;  length  about  '0022  ;  breadth  about  '0010.  The  distinctive 
character  of  this  species  ia  the  fineness  of  the  striffi.   (Plate  32,  fig.  20.) 

Donkin,  Q.  J.  M.  S.  Trans.,  1858,  p.  32,  PI.  iii.,  fig.  18;  and 
N.  H.  Brit.  Diat.,  p.  6,  Pl.i.,  fig.  3.  Donkm's  figures  represent  the  spe- 
cies as  much  larger  than  my  specimens  would  lead  me  to  regard  it. 
Ealfs,  inPritch.,  p.  899.     Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  184. 

Arran  Islands,  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Gal- 
way. 

Natncula  slliptiea,  (Kiitz.)     Fresh  water. 

Valve  elliptical ;  striae  of  the  marginal  band  distinctly  moniliform, 
converging  in  the  middle,  radiate  towards  the  ends ;  inner  striate  band 
very  narrow;  free  space  about  the  median  line  greatly  expanded, 
forming  a  rounded  rhombic  outline  ;  median  line  strongly  developed; 
length  about  -0020,  breadth  about  0011.     (Plate  32,  fig.  21.) 

Kiitz.  Bac,  p.  98,  T.  xxx.,  fig.  55.  Wm  Sm.,  B.  D.,  Vol.  ii.,. 
p.  92.     Balfs,  in  Pritch.,  p.  899.     Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  179. 


O'Meara — Report  on  the  Irish  Diatojnacece.  385 

Donldn,  N.  H.  Brit.  Diat.,  p.  7,  PI.  i.  fig.  6.  Grunow,  Verhand.  der 
K.K.  Zool.  Bot.  Gesell.,  Bandx.,  1860,  p.  531.  Heiberg,  De  Danske 
Diat.,  p.  81 .  Cleve,  Om  Svenska  och  Norska  Diat,  p.  226.  Schumann, 
Die  Diat.  der  Hohen  Tatra.,  p.  69.  Lagerstedt,  Sotvat.  Diat.  fran 
Spetsbergen  och  Beeren  Eiland,  p.  27.  Schmidt,  Atlas  der  Diat.,  T. 
▼ii.  figs.  31,  32.— Navicnla  ovalis,  Wm.  Sm.,  B.  D.,  Yol.  i.,  p.  48, 
PL  xvii.,  fig.  168a. 

Tacnmshane,  Co.  Wexford.  Lower  Lake,  Killarney,  Co.  Keny. 
Glenchree,  Powersconrt,  Co.  Wicklow.  Lucan,  Killakee,  Boherna- 
brena,  Co.  Dublin.  Peighcullen,  Boyal  Canal,  near  Enfield,  Co.  Kil- 
dare.     Pond,  near  the  city  of  Armagh. 

Tar,  eostata,  (O'Meara).     Fresh,  or  brackish  water. 

Valve  strongly  resembling  the  typical  species,  but  striae  distinctly 
costate,  and  intermediate  free  space  included  between  the  inner  mar- 
gins of  the  inner  striate  band  lanceolate,  but  slightly  expanded  in  the 
middle. 

This  variety  has  been  found  in  localities  where  marine  and  fresh 
water  forms  are  mixed. 

Breaches  near  Newcastle,  Co.  Wicklow.     Lough  Gill,  Co.  Kerry. 

Tar,  davidsoniij  (O'Meara).    Fresh  water. 

Valve  ovate-elliptical.  StriaB  very  fine,  moniliform;  space  included 
within  the  inner  margin  of  the  inner  striate  band  linear,  roundly 
expanded  in  the  middle. 

This  variety  was  first  brought  under  my  notice  by  my  valued  corres- 
pondent. Eev.  George  Davidson,  of  Logic,  Coldstone,  near  Aberdeen, 
who  foand  it  in  his  neighbourhood.  It  has  since  been  noticed  by  me 
in  various  localities  in  Ireland.  On  first  view  this  form  would  seem 
to  belong  to  Navicula  eestiva,  and  when  first  noticed  by  me  in  a  fresh 
water  gathering,  I  considered  it  was  a  stray  form  of  the  species  men- 
tioned, which  had  come  there  by  accident ;  but  subsequent  observation 
induced  me  to  give  up  this  view,  and  to  consider  the  form  a  well  marked 
variety.  It  is  likely  the  same  as  that  figured  by  Schmidt  in  his  Atlas 
der  Diat.,  T.  vii.,  fig.  33. 

Moist  Rock.  Portrush,  Co.  Antrim,  Lough  Mask,  near  Tourma- 
keady,  Lough  Neagh,  near  Lurgan,  Co.  Armagh. 

Var,  ovalis,  ("Wm.  Smith).     Fresh  water. 

Valve  linear,  oblong,  with  rounded  ends  ;  ^^ib  much  finer  than  in 
the  case  of  the  typical  form;  length  about  '0016,  breadth  about 
•0005.     (Plate  32,  fig.  22.) 

Navicula  ovalis,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  48,  PI.  xvii.,  ^o^,  153  a. 
Under  the  impression  that  this  form  and  Navicula  elliptica  were  iden- 
tical. Smith  abandoned  the  specific  name  of  ovalis,  and  merged  the  two 


386  Proceedings  of  the  Royal  Irish  Academy. 

foTXTLB  under  the  one  designation  Navicula  elliptica.  HoweTer  doee 
the  rcBemblance  must  be  acknowledged  to  be,  there  is  such  a  difference 
in  the  details  of  stnicture  as  to  require  notice.  Balls,  in  Pritch., 
p.  899,  regards  the  form  as  identical  with  Navicula  elliptica,  and  the 
same  view  is  adopted  by  the  following  authors :  Cleye,  Om  Sirenska 
och  Norska  Diat.,  p.  226.  Rabenhorst,  Fl.  Eur.  Alg.,  sect,  i.,  p.  179. 
Donkin,  N.  H.  Brit.  Diat.  Lagerstedt,  Sotvat.  Diat.  fran  Spetsbergen 
och  Beeren  Eiland,  p.  27,  and  probably  Grunow,  Yerhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  531.  Castracane  includes  the  two 
forms  under  the  designation  of  Navicula  ovalis ;  Catalogo  di  Diat.  rac- 
colte  nella  Yal.  Intrasca,  p.  12.  Schmidt,  treating  the  two  forms 
as  distinct  species,  describes  the  present  as  Navicula  ovalis ;  Atlas  der 
Diat.  T.  vii.,  figs.  34  and  35. 

Camolin,  Co.  Wexford.  Lough  Neagh,  near  Lurgan,  Co.  Armagh. 
Lough  Gill,  Co.  Kerry.     Lough  Moume  deposit. 

Tar,  parva,  (O'Meara).     Fresh  water. 

Valve  like  the  last  variety,  but  very  much  smaller,  and  the  stria- 
tion  extremely  indistinct ;  length  '0008,  breadth  0004. 

It  seems  not  improbable  that  this  variety  is  identical  with  that  de- 
scribed as  Navicula  oblongella  by  Schmidt,  Atlas  der  Diat.,  T.  vii., 
fig.  53. 

Camolin,  Co.  Wexford. 

(i)  Clavata. 

Valves  elliptical;  atria  in  two  distinct  bands^  one  marginal^  another 
close  to  the  median  line,  with  a  wide  elliptical  intervening  space.  Mar^ 
ginal  hand  of  stria  lunate  on  the  inner  margin, 

Navicula  clavata,  (Gregory).     Marine. 

Valve  broadly  elliptical;  ends  broadly  produced  and  rounded; 
strise  monilif orm,  marginal  band  broad,  narrowing  towards  the  ends ; 
inner  bands  of  striae  separated  from  the  median  line  by  a  narrow 
unstriate  space,  bending  outward  near  the  central  nodule,  where  they 
terminate  sharply,  making  a  wide  free  space  about  the  central  nodule ; 
space  intervening  between  the  inner  and  outer  bands  of  strisB  un« 
striate,  broad  and  lunate ;  length  about  *0050,  breadth  about  *0026. 
(Plate  32,  fig.  23.) 

Gregory,  Q.  J.  M.  8.  Trans.  1856,  p.  46,  PI.  v.,  fig.  17.  Ralfs, 
in  Pritch.,  p.  898.  Donkin,  N.  H.  Brit.  Diat.,  p.  15,  PL  ii.,  fig.  8.— 
Navicula  lyra,  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  178. 

Stomachs  of  Ascidians,  Co.  Clare.  Stomachs  o(  Ascidians,  Round* 
stone  Bay ;  stomachs  of  Ascidians,  Broadhaven  Bay,  Arran  Islands, 
Co.  Galway. 


O'Meara — Report  an  tJie  Irish  Diatomaceas,  387 

Ncmcula  hennedyi,  (Wm.  Sm.)    Marine. 

Valve  broadly  elliptical,  ends  not  produced ;  strise  monilif  oim ; 
inner  and  outward  bands  of  stria),  narrower  than  in  Kavicula  clavata, 
but  in  other  respects  very  similar ;  length  about  '0030,  breadth 
about  -0020.     (Plate  32,  fig.  24.) 

Wm.  8m.,  B.  D.,  Vol.  ii.,  p.  93.  Gregory,  Q.  J.  M.  S.  Trans., 
1856,  p.  40,  PI.  v.,  fig.  3.  Ralfs,  in  Pritch.,  p.  898.  Rab.  Fl.  Eur. 
Alg.  sect,  i.,  p.  178.  Donkin.  N.  H.  Brit.  Diat.,  p.  11,  PI.  ii.,  ^g.  3. 
Schmidt,  Atlas  der  Diat.,  T.  iii.,  figs.  17,  18. 

Stomachs  of  Ascidians,  Belfast  Lough,  Co.  Antrim.  Stomachs  of 
Ascidians,  Roundstone  Bay ;  stomachs  of  Ascidians,  Broadhaven  Bay, 
Arran  Islands,  Co.  Galway. 

Na^oieula  nehuloaa,  (Gregory).     Marine. 

Valves  in  outward  form  similar  to  those  of  Navicula  hennedyi,  but 
narrower ;  the  space  intervening  between  the  outer  and  inner  bands 
of  strise  obscurely  marked  with  very  fine  parallel  lines  of  puncta, 
which  do  not  extend  throughout ;  length  about  '0042,  breadth  about 
-0020.     (Plate  32,  fig.  25.) 

Gregory,  Diat.  of  Clyde,  p.  480,  PL  ix.,  fig.  8.  Ralfs,  in  Pritch;, 
p.  898.  Rab.  Fl.  Eur.  Alg.  sect,  i.,  p.  179.  Donkin,  N.  H.  Brit. 
Diat.,  p.  11,  PL  ii.,  fig.  2.  Schmidt,  Atlas  der  Diat.,  T.  iii.,  fig.  14. 
The  clouded  appearance  of  the  space  intervening  between  the  inner 
and  outer  bands  of  striae,  as  represented  in  the  figures  of  Gregory  and 
Donkin,  is  found  with  good  illumination  to  arise  i^om  the  fine  punctate 
striae  above  referred  to. 

Stomachs  of  Ascidians,  Roundstone  Bay,  Arran  Islands,  Co. 
Galway. 

Far.  suharhieulariSf  (O'Meara).     Marine. 

Valve  shorter  and  relatively  broader  than  that  of  the  typical 
species;  marginal  band  of  striae  relatively  broader;  that  next  the 
median  line  relatively  narrower ;  intermediate  space  between  the  inner 
and  outer  bands  of  striae  narrow,  and  occupied  by  irregularly  disposed 
puncta;  length  0024,  breadth  '0014.     (Plate  32,  fig.  26.) 

Arran  Islands,  Stomachs  of  Ascidians,  Roundstone  Bay,  Co. 
Galway. 

Navieula  pr€eiexta^  (Ehr.)    Marine. 

Valve  broadly  elliptical ;  marginal  band  of  striae  broad,  distinctly 
moniliform ;  me£an  bands  of  striae  broad,  distinctly  moniliform ;  inter- 
mediate space  between  the  outer  and  inner  bands  of  striae  ornamented 
with  irregularly  arranged  large,  round  puncta ;  free  unstriate  space 
between  the  median  line  and  the  inner  margins  of  the  inner  band  of 
striae  expanding  in  the  middle,  with  a  narrow  stauroform  band ;  length 
about  -0040,  breadth  about  -0025.     (Plate  32,  fig.  27.) 

Ehrenberg,  in  Proceedings  of  Berlin  Acad.,   1840,  p.  20.     Kiitz. 


388  Proceedings  of  the  Royal  Irish  Academy. 

Bac.,  p.  98.  Gi-egory,  Diat.  of  Clyde,  p.  481,  PL  ix.,  fig.  11.  Rails, 
in  Pritch.,  p.  898.  Rab.  PL  Eur.  Alg.  sect,  i.,  p.  183.  Donkin,  N.  H. 
Brit.  Diat.,  p.  10,  PL  ii.,  fig.  1.  Schmidt,  Atlas  der  Diat.,  T.  iii., 
fif.  31. 

Arran  Islands,  Stomachs  of  Ascidiaos,  Koundstone  Bay;  stomachs 
of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Navicula  tnoreiif  N.  Sp.     Marine. 

Valve  very  large,  broadly  elliptical,  somewhat  rhombical ;  marginal 
band  of  striae  broad  in  the  middle,  diminishing  towaixls  the  ends ; 
median  band  of  strisB  narrow,  terminating  considerably  short  of  the 
central  nodule ;  intermediate  space  between  the  inner  and  outer  bands 
of  striaB  broad,  unstriate ;  striae  fine,  but  distinctly  moniliform ;  nearly 
parallel  in  the  middle,  slightly  radiate  towards  the  ends ;  length  -0075, 
breatlth  -0037.     (Plato  32,  fig.  28.) 

Kavicula  kittoniana,  Schmidt,  Atlas  der  Diat.,  T.  ii.,  &g.  10. 
The  form  having  been  exhibited  by  me  some  years  ago  at  the  Meeting 
of  the  Dublin  Microscopical  Club,  under  the  name  of  Navicula  moreii, 
the  latter  designation  has  the  priority.  Schmidt's  locality  is  Kio 
Janeiro. 

Stomachs  of  Ascidians,  Broadhaven  Bay ;  stomachs  of  Ascidians, 
Roundblone  Bay,  Co.  Gaiway. 

Navicula  sandn'ana,  (Gmnow).    Marino. 

Yalvo  nearly  orbicular ;  marginal  band  of  hfrlte  naiTow,  of  equal 
breadth  till  near  the  ends,  where  it  widens,  and  then  suddenly  nar- 
rows; median  band  of  striae  very  narrow,  not  reaching  the  median 
line,  and  terminating  at  some  distance  from  the  central  nodule  ;  inter- 
mediate space  between  the  inner  and  outer  bands  of  suiic  wide,  orna- 
mented with  irregularly  disposed  indistinct  puncta,  and  having  in 
the  middle  a  naiTow,  longitudinal  lunate  band  of  small,  but  distinct, 
puncta;  striae  of  the  marginal  band  monilifoim,  radiate;  stri®  of  the 
inner  band  punctate,  and  parallel ;  length  about  -0040,  breadth  about 
•0030.     (Plate  32,  fig.  29.) 

This  form  was  exhibited  by  me  at  a  Meeting  of  the  Dublin  Micix)- 
scopical  Club  as  Navicula  coelata,  but  subsequently  I  discovered  that 
the  species  had  been  described  in  1863  by  Grunow  as  Navicula  san- 
driana,  which  designation,  having  the  priority,  must  be  penuitted  to 
stand. 

Gninow,  Ycrhand.  dor  K.  Zool.  Bot.  GeselL,  Band  xii.,  1863, 
p.  153,  T.  iv.,  fig.  5.  Schmidt,  Atlas  der  Diat.,  T.  iii.,  fig.  10. 
Grunow's  locality  for  the  species  is  the  Adriatic  Sea.  I  may  hero 
remark  that  my  specimens  differ  from  those  figured  by  Grunow  and 
Schmidt,  by  the  fact  that  in  mine  the  outer  band  of  striae  expands 
perceptibly  near  the  ends,  a  feature  which  is  not  noticeable  in  the 
figures  referred  to  above. 

Stomachs  of  Ascidians,  Roundstone  Bay,  Co.  Galway. 


O'Meara — Report  on  the  Irkh  Diatomacece.  389 

Ndvietda  francisea^  N.  S.     Marine. 

Valve  nearly  orbicnlar ;  marginal  band  of  striae  narrow ;  median 
band  of  strise  narrow,  distant  from  median  line,  leaving  a  lanceolate, 
nnstriate  space  between  the  inner  margins ;  intermediate  space 
between  the  inner  and  outer  bands  of  striae  broad,  unstriate ;  strise 
moniliform,  parallel  in  the  middle,  radiate  towards  the  ends ;  length 
•0033,  breadth  0030.     (Plate  32,  fig.  30.) 

Stomachs  of  Ascidians,  Ronndstone  Bay,  Co.  Galway. 

Navicula  hihemicay  N.  S.     Marine. 

Valve  elliptical  oblong ;  marginal  band  of  striae  narrow,  slightly 
broader  in  the  middle  than  at  the  ends ;  inner  band  of -striae  narrow, 
roundly  expanded  at  the  ends ;  intermediate  space  between  the  inner 
and  outer  bands  of  striae  broad,  ornamented  with  irregularly  disposed 
distinct  puncta;  striae  of  the  marginal  band  linear,  with  moniliform  striae 
interposed,  parallel  in  the  middle,  radiate  towards  the  ends ;  striae  of 
the  inner  band  punctate,  parallel.     (Plate  32,  fig.  31.) 

Stomachs  of  Ascidians,  Boundstone  Bay ;  Arran  Islands,  Co.  Gal- 
way. 

Navieula  nitesceru.     (Gregory).     Marine. 

Valve  elliptical,  lanceolate  ;  striae  apparently  strongly  costate, 
divided  by  a  longitudinal  sulcus  into  two  nearly  equal  compartments ; 
free  space  between  the  inner  margins  of  the  inner  bands  of  striae  nar- 
row, lanceolate ;  slightly  expanded  in.  the  middle.    (Plate  32,  fig.  32.) 

Ealfs,  in  Pritch.,  p.  898.  Rab.  Fl.  Eur.  Alg.  sect,  i.,  p.  179. 
Donkin,  N.  H.  Brit.  Diat.,  p.  8,  PI.  i.  fig.  7. — Navicula  smithii,  var. 
nitescens,  Gregory,  Diat.  of  Clyde,  p.  487,  PI.  ix.,  fig.  16. — Pinnularia 
arraniensis,  O'Meara,  Q.  J.  M.  S.,  1867,  p.  116,  Pi.  v.,  fig.  6. 

Arran  Islands.  Stomachs  of  Ascidians,  Roundstone  Bay;  sto- 
machs of  Ascidians,  Broadhavon  Bay,  Co.  Galway. 

Navicula  riehardsoniana,   N.  8.     Marine. 

Valve  narrow,  elliptical;  ends  rounded ;  inner  band  of  striae  broad 
outer  band  of  striae  very  narrow ;  striae  strongly  costate,  sub-distant, 
radiate;  length  0024,  breadth   0006.     (Plate  32,  fig.  33.) 

This  form  strongly  resembles  Navicula  nitescwis,  but  differs  so 
much  as  to  be  entitled  to  be  regarded  as  a  distinct  species. 

Stomachs  of  Ascidians,  Brbadhaven  Bay,  Co.  Galway. 

Navicula  stoheaianay  N.  S.    Marine. 

Valve  large,  rhombic,  lanceolate;  marginal  striate  band  wide; 
inner  striate  band  narrow,  elevated  above  the  surface  ;  free  space  in- 


390  Proceedings  of  the  Royal  Irish  Academy. 

eluded  within  the  inner  margins  of  the  inner  striate  bands  narrow,  linear, 
forming  in  the  middle  a  very  narrow  stauroform  line ;  space  interme- 
diate between  the  outer  and  inner  striate  bands  occupied  by  lines  of 
striaB,  which  are  prolongations  of  the  striae  of  the  marginal  band ; 
striae  close,  punctate,  radiate;   length  "0045,  greatest  breadth -0018. 

This  form  is  one  of  very  rare  occurrence,  only  three  specimens 
having  been  noticed.  The  only  forms  I  have  seen  figured  which  bear 
resemblance  to  this  very  striking  species  are  those  of  Mastogloia  jeli- 
ninekiana,  Grunow,  Beise  S.  M.  Novara  um  die  Erde,  T.  i.  A.,  fig.  1 1 ; 
and  Navicula  irrorata,  Schmidt,  Atlas  der  Diat.,  T.  ii.,  fig.  19.  As 
to  the  former,  even  a  cursory  examination  suffices  to  show  that  this 
form  is  perfectly  distinct.  As  to  the  latter,  the  inner  and  outer  bands 
of  striae  are  separated  by  an  intervening  blank  space,  whereas  in  the 
present  case  the  corresponding  intermediate  space  is  distinctly  striate. 

This  beautiful  species  I  wish  to  identify  with  the  name  of  the 
present  respected  President  of  the  Royal  Irish  Academy.  (Plate  32, 
fig.  34.) 

Stomachs  of  Ascidians,  lloundstone  Bay;  stomachs  of  Ascidians, 
Broadhaven  Bay,  Co.  Galway. 


(j)  Lyrat(B, 

Similar  to  the  last  suh-group,  and  distinguished  hy  the  bending  in  at 
ihs  middle  of  the  marginal  striate  hand,  which  conseqtiently  is  hilunate  on 
the  inner  margin.  The  intermediate  free  space  is  more  or  less  distinctly 
lyrate, 

Navicfda  tcrightii,  (O'Meara).     Marine. 

Valve  linear  elliptical ;  ends  broadly  produced ;  marginal  band  of 
fltriae  tolerably  wide,  projecting  inwards  slightly  in  the  middle ;  strisd 
moniliform,  nearly  parallel  at  the  middle,  sHghtiy  radidte  towards  the 
ends ;  inner  band  of  striae  narrow,  expanded  at  the  ends ;  intermediate 
space  between  the  inner  and  outer  bands  of  striae  wide,  unstriate;  length 
-0045,  breadth  -0018.     (PI.  32,  fig.  35.) 

Navicula  wrightii,  var.  Q.  J.  M.  8.,  1867,  p.  116,  PL  v.,  fig.  46.— 
I^avicula  caribea,  Schmidt,  Atlas,  T.  ii.,  fig.  17. 

Arran  Islands ;  Stomachs  of  Ascidians,  Koundstone  Bay ;  Stomachs 
of  Ascidians,  Broadhaven  Bay,  Co.  Ghdway. 

Navictda  spectdbilisj  (Gregory).     Marine. 

Valve  broadly  elliptical;  marginal  band  of  striae  broad  in  the 
middle,  and  gradually  decreasing  towards  the  ends ;  inner  band  of 
striae  wide ;  striae  moniliform,  nearly  parallel  in  the  middle,  slightly 
radiate  towards  the  ends  ;  intermediate  space  between  the  inner  and 
outer  bands  of  striae    very  wide,  unstriate,  but  interrupted  by   a 


O'Meara — Report  on  the  Imh  Diatomaceee.  391 

narrow  longitudinal  ncbulons  belt,  which  runs  conformably  with  the 
inner  edge  of  the  marginal  band  of  strite;  length  -0044,  breadth 
•0025. 

Gregory,  Diat.  of  Clyde,  p.  481,  PL  ix.,  fig.  10.  Ralfs,  in 
Pritch.,  p.  898.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  178.  Donkin,  N.  H. 
Brit.  Diat.,  p.  12,  PL  ii.,  fig.  5.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  226. 

Arran  Islands ;  Stomachs  of  Ascidians,  Eoundstone  Bay ;  Stomachs 
of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Var.  3uh'&rhieulan'8f  (O'Meara).     Marine. 

In  all  respects  resembling  the  typical  species,  but  nearly  orbicular ; 
the  marginal  band  of  striae  relatively  broader,  the  inner  band  of  striae ; 
as  well  as  the  intermediate  space  between  the  inner  and  outer  striate 
bands  much  narrower;  length  -0024,  breadth  '0018.  (Plate  32, 
fig.  36.) 

jS'avicula spectabilis,  var.?  Schmidt,  Atlas  der  Diat.,  T.  ii.  fig.  31. 

Arran  Islands ;  Stomachs  of  Ascidians,  Eoundstone  Bay ;  Stomachs 
of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Navicula  lyra^  (Ehr.)     Marine. 

Valve  linear  elliptical ;  ends  broadly  produced ;  marginal  band  of 
strise  broad ;  inner  band  broad,  incurved  in  the  middle ;  intermediate  free 
space  between  the  inner  and  outer  bands  of  stria)  very  narrow ;  ends 
pointed  and  directed  outwards ;  striae  moniliform  ;  length,  about  '0040, 
breadth,  about  -0014.     (Plate  33,  fig.  1.) 

Kutzing,  Bac,  p.  94,  T.  xxviii.,  fig.  55,  who  refers  the  species  to 
Ehrenberg.  Gregory,  Diat.  of  Clyde,  p.  485,  PL  ix.,  fig.  13J.  Ralfs, 
in  Pritch.,  p.  897,  who  remarks,  **  Either  Navicula  lyra  is  very  varia- 
ble, or  more  than  cne  species  has  been  included  under  the  name." 
Heiberg,  De  Dansko  Diat.,  p.  80,  who  includes  this  form  and  the 
variety  elliptica.  Cleve,  Om  Svenska  oeh  Norska  Diat.,  p.  226. 
Donkin,  N.  H.  Brit.  Diat.,  p.  14,  PL  ii.,  fig.  7.  Schmidt,  Atlas  der 
Diat.,  T.  ii.,  fig.  16. 

River  Slaney,  Killurin,  Bannon,  Co.  Wexford.  Malahide,  Port- 
mamock,  Co.  Dublin.  Seaweeds,  Portrush,  Co.  Antrim.  Caum 
Lough,  near  Tralee,  Lough  Gill,  Co.  Kerry.  Salt  marsh,  Kilcool,  Co. 
Wicklow.  Kilkee,  Co  Clare.  Arran  Islands ;  Stomachs  of  Asci- 
dians, Broadhaven  Bay ;  Stomachs  of  Ascidians,  Roundstone  Bay  Co. 
Galway.     Stomachs  of  Ascidians,  Belfast  Lough. 

Var,  ettiptt'ea,  (Wm.  Smith).     Marine. 

Valve  elliptical ;  greatly  attenuated  at  the  ends  ;  marginal  band  of 
strise  very  broad ;  inner  band  of  stria)  narrow ;  intermediate  free 
space  between  the  inner  and  outer  striate  bands  narro'^;  incurved  in 


392  Proceedings  of  the  Royal  Irish  Academy. 

the  middle,  coiivcrg;ing  at  the  attenuated  extremities ;  striaa  obviouftl  j 
moniliform ;  length,  about  -0056,  breadth,  about  -0024.  (Plate  33, 
fig.  2.) 

This  form  was  first  dcBcribed  by  Wm.  Smith,  who  doubtfully 
considered  it  a  sporangia!  variety  of  XaTicula  elliptica,  B.  D.,  Vol.  i., 
p.  48,  PL  x^'ii.,  fig.  152  a.  Subsequently  the  same  author  regarded 
it  as  identical  with  Navicula  lyra,  Ehr.,  B.  D.,  Vol.  ii.,  p.  93 ;  but 
judging  by  the  figure  which  Kutzing  has  given  of  the  latter,  there 
can  be  little  doubt  that  the  forms  are  not  altogether  identical.  Still, 
so  similar  are  they,  that  it  seems  desirable  to  represent  them  as 
merely  varieties.     Schmidt,  Atlas  der  Diat.,  T.  ii.  fig.  29. 

Stomachs  of  Ascidians,  Belfast  Lough.  Stomachs  of  Ascidians, 
Kilkee,  Co.  Clare.  Arran  Islands ;  Stomachs  of  Ascidians,  Roundstone 
Bay ;  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Gal  way.  Bjdly- 
sodare,  Co.  Sligo.     Bjinnow,  Co.  Wexford. 

Var,  grunoviiy  (O'Meara).     Marine. 

Valve  broadly  elliptical;  marginal  band  of  striso  very  broad; 
inner  band  of  strias  narrow;  intermediate  space  between  the  inner 
and  outer  bands  of  striie  narrow,  converging,  and  anastomosing  at  the 
ends ;  stria3  verv  close,  radiate,  minutely  punctate ;  length  '0028, 
breadth  -0015.     (Plate  33,  fig.  3.) 

Grunow,  Vcrhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  532,  T.  v.,  fig.  22.  The  author  just  named  regards  the  form  as 
identical  with  Navicula  Lyra,  Ehr.,  as  described  by  Kiitzing,  Bac, 
p*  96,  T.  xxviii.,  fig.  55 ;  but  comparison  of  specimens  of  both  will 
convince  the  observer  that  the  forms  are  not  identical ;  so  distinct  are 
their  details  that  the  present  form  might  almost  be  regarded  as  entitled 
to  a  distinctive  specific  name. 

Arran  Islands ;  Stomachs  of  Ascidians,  Broadhaven  Bay ;  Stomachs 
of  Ascidians,  Boundstone  Bay,  Co.  Galway. 

Tar,  minoTy  (Gninow).     Marine. 

This  variety  resembles  that  last  described,  but  differs  from  it  in 
the  fqllowing  characters ;  the  form  is  much  smaller,  the  ends  are  broadly 
rounded,  and  the  lyrate  space  between  the  two  bands  of  striae  is  much 
more  convex  ;  length  -0015,  breadth  .0009.    (Plate  33,  fig.  4.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gcscll.,  Band  x.,  1860, 
p.  532,  PI.  v.,  fig.  23. 

Stomachs  of  Ascidians,  Boundstone  Bay  ;  Arran  Islands,  Co. 
Galway. 

Var.forcipata,  (Greville).     Marine. 

Valve  elliptical,  oblong ;  marginal  and  inner  bands  of  striae  sepa- 
rated by  a  broad  lyrate,  blank  space ;  convergent  at  the  ends ;  stri®, 
minutely  moniliform;  length  about  -0024,  breadth  about  -0010. 

GreviUe,  Q.  J.  M.  S.  1859,  p.  83,  PI.  vi.,  figs.  10,  il.  RiUfs,  in 
Pritch.,  p.  897.     Hub.  Fl.  Eur.,  Alg.,  sect,  i.,  p.  178.    Donkin,  K  H. 


O'Meara — Report  on  the  Irish  Diatomacece,  393 

Brit.  Diat.,  p.  12,  PI.  ii.,  fig.  4.     And  likely  the  same  as  that  figured 
hy  Schmidt,  Atlas  der  Diat.,  T.  ii.,  fig.  36. 

Arran  Islands;  Stomachs  of  Ascidians,  Roundstone  Bay;  Sto- 
machs of  Ascidians,  Broadhaven  Bay,  Co.  Galway.  Bannow,  Co. 
Wexford.  Malahide,  Portmamock,  Piles  of  wooden  bridge,  Dolly- 
mount  strand,  Dalkey,  Co.  Dublin.  Bostrovor,  Dundrum  Bay,  Co. 
Down.     Lough  Gill,  Co.  Kerry. 

Var,  ahrupta,  (Gregory).     Marine. 

Like  the  last  desciibed  variety,  but  the  strise  are  costate,  and  the 
intermediate  Ivrate  free  space  does  not  extend  so  near  the  ends. 

Gregoiy,  Diat.  of  Clyde,  p.  486,  PI.  ix.,  fig.  14.  Bab.  Fl.  Eur., 
Alg.,  sect,  i.,  p.  178.  Donkin,  N.  H.  Brit.  Diat,  p.  13,  PI.  ii.,- 
fig.  6.  Gregory  and  Donkin  figure  the  species  with  obscurely  moni- 
lif orm  striffi ;  and  therefore  I  have  a  doubt  of  the  identity  of  the  pre- 
sent variety  with  that  so  described.  Supposing  the  figures  referred  to 
be  exact  in  this  particular,  I  could  scarcely  distinguish  between  the 
former  and  Navicula  lyra,  var.  elliptica. 

Arran  Islands;  Stomachs  of  Ascidians,  E^undstone  Bay;  Sto- 
machs of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Far.  cosfata,  (O'Meara).     Marine. 

Valve  broadly  elliptical ;  marginal  band  of  striae  broad ;  inner  band 
of  stria5  narrow ;  striae  distinctly  costate,  close,  parallel  in  the  middle, 
slightly  radiate  towards  the  ends,  which  latter  are  slightly  cuneate ; 
intermediate  lyrate  space  very  narrow,  convergent  at  the  ends,  and 
reaching  to  the  apices;  length  '0024,  breadth  '0012. 

AiTan  Islands;  Stomachs  of  Ascidians,  Broadhaven  Bay;  Sto- 
machs of  Ascidians,  Iloundstone  Bay,  Co.  Galway. 

Var.  seductih'Sj  (Griindler).     Marine. 

Valve  narrow,  linear-elliptical ;  marginal  band  of  striae  relatively 
wide ;  inner  band  of  striae  narrow ;  striae  very  fine,  linear,  parallel  in 
the  middle,  slightly,  radiate  towards  the  ends,  lyrate  smooth  space 
very  narrow;  length  about  -0020,  breadth  about  -0006. — Xavicula 
seductilis  (Griindl),  Schmidt,  Atlas  der  Diat.,  T.  ii.,  fig.  35. 
Yokohama.  (Plate  33,  fig.  5.) 

Stomachs  of  Ascidians,  Boundstone  Bay,  Co.  Gtilway. 

Tar.  eonstricta,  (O'Meara).     ^farine. 

Valve  linear,  elliptical,  slightly  constricted  in  the  middle,  ends 
cuneate,  rounded  at  the  extremity;  striae,  fine,  moniliform,  lyrate; 
free  space  narrow,  converging  at  the  ends ;  length  '0042,  greatest 
breadth  -0016,  breadth  in  the  middle  -0015.     (Plate  33,  fig.  6.) 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 


394  Proceedings  of  the  Royal  Truth  Academy, 

Navieuh  pygnuea,  (Eiitz..)     Marine  or  brackish  water. 

Valve  linear,  elliptical ;  marginal  band  of  striae  narrow,  with  a  dis- 
tinct ridge  on  the  inner  margin ;  inner  band  of  strise  relatively  broad, 
reaching  the  median  line,  and  having  a  distinct  ridge  on  the  outer  mar- 
gin ;  striae  fine,  linear,  nearly  parallel ;  space  intermediate  between 
the  inner  and  outer  bands  of  strisB  narrow,  lyrate ;  apparently  nn- 
Btriate,  but  on  closer  inspection  it  will  be  found  that  the  strias  which 
seem  to  be  interrupted  are  really  pervious;  length  about  '0015; 
breadth  about  '00066,  but  often  of  much  larger  dimensions.  (Plate 
33,  fig.  7.) 

Wm.  Smith  (B.  D.,  Vol.  ii.,  p.  91),  who  attributes  the  species  to 
Kiitzing.  Rabenhorst  (Siissw.  Diat.,  p.  39)  refers  to  a  form  under  this 
name  without  a  figure  ;  the  species  is  not  correctly  included  among 
those  incidental  to  fresh  water.  Half s,  in  Pritch. ,  p.  899,  who  says  *  *  the 
species  occurs  in  brackish  or  fresh  water ; "  but  though  often  found  by  me 
in  marine  gatherings,  it  never  once  occurred  to  me  in  fresh  water. 
Donkin,  N.  H.  Brit.  Diat.  p.  10,  PI.  i.,  fig.  10.  Lagerstedt,  Sotvat. 
Diat.  fran  Spetzbergen  och  Beeren  Eiland,  p.  27. — Navicula  minutula^ 
Wm.Sm.,  B.D.,  Vol  i.,p.  48,  PI.  xxxi.,  fig.  274. 

Bannow,  salt  ditch  near  town  of  Wexford,  River  Slaney,  near 
Killurin,  Tacumshane,  Co.  Wexford.  Malahide,  Portmamock,  Piles 
of  wooden  bridge,  Dollymount  Strand,  Co.  Dublin.  Galway  Bay, 
near  town  of  Galway.  Portnacrush,  Co.  Donegal.  Lough  Gill,  Co. 
Kerry.     On  seaweeds,  Kilkce,  Co.  Clare. 

Var.  cuneatay  (O'Meara).     Marine. 

Valve  linear,  elliptical,  with  cuneate  ends;  marginal  band  of  striae 
broad ;  inner  band  of  strias  narrow ;  striaj  coarse,  linear,  distant, 
parallel  in  the  middle,  slightly  radiate  towards  .the  ends,  lyrate ; 
free  space  narrow,  and  sometimes  difficult  to  detect;  length  '0017; 
breadth  -0010.     (Plate  33,  fig.  8.) 

Stomachs  of  Ascidians,  Broadhavcn  Bay,  Co.  Galway. 

(k)  TrifoBciata, 

Distinguished  by  having  the  intermediate  space  between  the  inner  mar- 
gins of  the  marginal  bands  of  striiB  divided  into  three  distinct  longitudinal 
compartments,  one  about  the  median  line,  and  one  on  either  side  of  the  same. 


t  Kot  cofistric/ed  in  the  middle. 

Navicxda  expleta,     N.  S.     Marine. 

Valve  broadly  elliptical ;  median  compartment  nearly  linear,, 
slightly  incurved  towards  the  ends,  next  compartments  narrow, 
lunate ;  marginal  band  of  strias  relatively  wide ;  striae  linear,  undu- 
late, divided  by  about  five  longitudinal  sulci;  length  about '0018  ; 
breadth  about  '0012.     (Plate  33,  fig.  9.) 

This  form  appears  to  me  obviously  identical  with  that  described 


0*Meara — Report  on  the  Irish  DiatomaceoB,  395 

uider  the  name  of  Navicula  notabilis,  passing  into  the  variety  expleta, 
by  Schmidt,  Atlas  der  Diat.,  T.  yiii.,  figs.  50,  51  and  52.  It  seems 
to  be  perfectly  distinct  from  Kavicida  notabilis,  and  deserving  of 
being  marked  by  a  distinct  specific  name. 

Stomachs  of  Ascidians,  Koundstone  Bay ;  Stomachs  of  Ascidians, 
Broadhaven  Bay ;  Arran  Islands,  Co.  Galway. 

Navieula  eynthta,  (Schmidt).    Marine. 

Yalves  broadly  elliptical;  ends  rounded  ;  median  compaiiment  nar- 
row, linear,  slightly  incurved  at  the  ends,  and  slightly  constncted  in 
the  middle  compartment  at  either  side,  narrovr,  arcuate,  nn striate  ; 
marginal  striate  band  broad ;  striae  fine,  close,  linear,  slightly  radiate, 
divided  into  two  nearly  equal  parts  by  a  longitadinal  sulcus ;  length 
•0012,  breadth  -0007.     (Plate  »3,  fig.  10.) 

Schmidt,  Atlas  der  Diat.,  T.  viii.,  fig.  41.  This  figure  does  not 
indicate  the  longitudinal  sulcus  which  in  my  specimens  divides  the  mar- 
ginal band  of  stries  into  two  compartments ;  still  I  am  disposed  to 
regard  .the  present  form  as  at  best  a  variety  of  the  form  described  by 
Schmidt. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Navicula  samegana,  (Grunow).  Marine. 
Yalve  linear,  elliptical,  ends  rounded ;  median  compartment  narrow, 
linear  throughout ;  compartments  on  either  side  nanow,  very  slightly 
arcuate,  striate ;  marginal  striate  band  relatively  broad ;  strias  linear, 
sub-distant,  parallel  in  the  middle,  slightly  radiate  towards  the  ends  j 
length  -0020,  breadth  -0009.     (Plate  33,  ^z-  ll-) 

Schmidt,  Atlas  der  Diat.,  T.  viii.,  fig.  27,  who  attributes  the  spe- 
cies to  Grunow,  but  I  cannot  find  it  noticed  in  any  of  the  many  papers 
of  that  author  which  I  have  had  the  opportunity  of  consulting. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Naoieula  arranienats,  N.  S.     Marine. 

Yalve  small,  elliptical ;  median  compartment  narrow,  slightly  con- 
stricted in  the  middle,  slightly  incurved  at  the  ends ;  compartments  at 
either  side  narrow,  arcuate,  striate ;  marginal  band  of  strise  narrow ; 
striae  strongly  costate,  distant,  nearly  linear.  Length  *0012,  breadth 
•0006.     (Plate  33,  fig.  12.) 

Arran  Islands,  Co.  Galway. 

Na/oieula  schmidtiiy  N.  S.     Marine. 

Yalve  broadly  elliptical,  ends  rounded ;  middle  compartment  nar- 
row, linear,  strongly  marked ;  very  slightly  constricted  in  the  middle, 
very  slightly  incurved  at   the   ends;   compartments  at  either  aide 

m.i.A.  PBGC,  BXB.  n.,  VOL.  n.,  sdxircB.  2  U 


396  Praeeeding$  of  the  Bayal  Iriih  Academy. 

arcuate,  oiiBtriate;  marginal  band  of  striiB  relatirely  broad;  rtrua 
coarse,  costate,  nearly  parallel  in  tbe  middle,  but  distinctly  radiate 
towards  the  ends.     (Plate  33,  fig.  17.) 

Nayicula  eugenia,  Erit.,  form  from  Java,  Schmidt,  Atlas  der  Diat., 
T.  yiii.  fig.  45.  In  my  form  the  costss  are  stronger  and  more  remote 
than  in  the  form  described  by  Schmidt ;  still  I  have  little  hesitation 
in  regarding  them  as  the  same  species. 

Arran  Islands.  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Oal- 
way. 

Ne/oieula  eugenia^  (Schmidt),     llarine. 

Valve  linear  elliptical ;  ends  rounded ;  median  compartment  slightly 
constricted  in  the  middle,  slightly  incurved  at  the  ends ;  compartments 
at  either  side  arcuate,  nearly  as  wide  as  the  marginal  band  of  striie, 
striate ;  stria  fine,  linear,  nearly  parallel  throughout ;  length  -0002, 
breadth,  0007.     (Plate  33,  fig.  13.) 

Schmidt,  Atlas  der  Diat.,  T.  viii.,  ^f^.  44.    From  Campeachy  Bay. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Gkdway. 

NavieuU  teuUUum,  (O'Meara).    Marine. 

Valve  broadly  elliptical,  narrowed  and  rounded  at  the  ends ;  median 
compartment  broad,  Unear,  slightly  incurved  at  the  ends,  slightly  con- 
stricted in  the  middle  ;  central  nodule  large,  quadrangular,  but  slightly 
incurved  at  the  ends ;  compartments  at  either  side  narrow,  unstriate,  the 
ends  of  the  striae  of  the  marginal  band  sometimes  appearing  as  beads  on 
the  outer  edge ;  marginal  striate  band  broad :  strin  costate,  nearly 
parallel  in  the  middle,  more  and  more  radiate  towards  the  ends ;  length 
about  0025,  breadth  about  0015.     (Plate  33,  fig.  14.) 

Pinnularia  scutellum,  O'Meara,  Q.  J.  M.  S.,  1869,  p.  151,  PL  xii. 
fig.  5. 

Arran  Islands,  Co.  Galway. 

Navicula  subarhieularu,  (Gregory).     Marine. 

Valve  suborbicular,  linear;  median  compartment  wide,  with  mar- 
gins distinctly  marked,  slightly  infiezed  at  the  ends,  considerably 
constricted  in  the  middle ;  compartments  at  either  side  tolerably  broad ; 
bilunate  on  the  inner  margin ;  marginal  striate  band  broad,  lunate  on 
inner  edge;  striss  radiate,  finely  costate,  with  obscure moniliform  strise 
interposed ;  the  costce  only  continued  across  the  contiguous  compart- 
ment; length  0025,  breadth  '0016.     (Plate  33,  fig.  15.) 

Ralfs,  in  Pritch.,  p.  898  ;  Donkin,  N.  H.  Brit.  Diat.,  p.  9,  PI.  i., 
fig.  9.  Schmidt,  Atlas  der  Diat.,  T.  viii.,  fig.  5. — ^Navicula  smithii^ 
var.  suborbicularis,  Gregory,  Diat.  of  Clyde,  p.  15,  PI.  ix.,  fig.  17. 

Ascidians,  Boundstone  Bay ;  Arran  Islands,  Co.  Galway. 


O'Meara — Report  on  the  Irish  Diatom<tcecB,  397 

Var.  forfictUaf  (O'Meara).     Marine. 

Yalve  elliptical^  median  compartment  as  in  the  typical  species ; 
compartments  at  either  side  very  much  narrower ;  marginal  striate 
band  wide^  projecting  towards  the  central  nodule;  inner  margin  bilu- 
nate ;  strise  radiate,  costate,  with  obscure  monilif orm  strie  interposed, 
the  costsB  only  penetrating  the  contiguous  compartment;  length 
•0023,  breadth  -0014.     (Plate  33,  fig.  16.) 

Schmidt,  Atlas  der  Diat.,  T.  viii.,  fig.  3. — ^Pinnularia  forficula, 
O'Meara,  Q.  J.M.  S.,  1867,  p.  117,  PL  v.,  fig.  9. 

Arran  Islands,  Co.  Gbdway. 

Var.  parva,  (Schmidt).     Marine. 

Valve  linear,  elliptical ;  median  compartment  narrow,  inflexed  at 
the  ends,  slightly  constricted  in  the  middle ;  compartment  at  either 
side  very  narrow,  bilunate ;  marginal  striate  band  broad,  bilunate  on 
the  inner  margin;  striae  fine,  linear,  nearly  parallel  throughout; 
length  -0014,  breadth  -0008. 

Schmidt,  Atlas  der  Diat.,  T.  yiii.,  figs.  1  and  2. 

Stomachs  of  Ascidians,  Broadhavcn  Bay,  Co.  Galway. 

N<w%€ula  coffeiformiif  (Schmidt).     Marine. 

Valve  small,  broadly  elliptical ;  median  compartment  narrow,  in- 
dexed at  the  ends,  slightly  constricted  in  the  middle ;  compartments 
on  either  side  narrow ;  median  striate  band  relatively  wide ;  strisd  fine, 
linear,  slightly  radiate;  length  -0010,  breadth  -0006.  (Plate  83, 
fig.  18.) 

Schmidt,  Atlas  der  Diat.,  T.  viii.,  fig.  7. 

Arran  Islands,  Co.  Galway. 


f  f  Valve  constricted  to  the  middle. 

Navicuh  eudoxia,  (Schmidt).     Marine. 

Valve  elliptical,  slightly  constricted,  ends  broadly  rounded ;  median 
compartment  narrow,  inflexed  at  the  ends,  slightly  constricted  in  the 
middle;  compartments  at  either  side  narrow,  stnate;  strice  linear, 
nearly  parallel  and  very  faint ;  marginal  striate  band  narrow ;  strise 
linear,  slightly  convergent  in  the  middle,  slightly  radiate  towards 
the  ends;  length  '0016,  breadth  at  the  constriction  *0007,  greatest 
breadth  -0008.     (Plate  33,  fig.  19.) 

Schmidt,  Atlas  der  Diat.,  T.  viii.,  fig.  19. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

3172 


898  Proceedings  of  the  Royal  Irish  Academy. 

Navieula  donhiniay  (O'Meara).    Marine. 

YalTO  slightly  constricted;  ends  somewhat  cuneate,  Fonnded; 
median  compartment  narrow,  slightly  inflezed  at  the  ends,  slightly 
constricted  in  the  middle ;  compartments  at  either  side  narrow,  arcu- 
ate, having  very  faint  striae;  marginal  striate  band  narrow;  strise 
costate,  coarse,  sub-distant;  nearly  parallel  in  the  middle,  slightly 
radiate  towards  the  ends;  length  *0015,  breadth  at  the  constriction 
•0006 ;  greatest  breadth  '00066.     (Plate  33,  fig.  20.) 

Schmidt,  Atlas,  T.  zii.,  fig.  63. — Navicula  musca,  Donkin,  N.  H. 
Brit.  Diat.,  p.  60,  PI.  vii.,  fig.  6,  exclusive  of  Synonyms. 

Airan  Islands;  Stomachs  of  Ascidians,  Boundstone  Bay;  Sto- 
machs of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Navicula  marffinaia,  (O'Meara).     Marine. 

Yalve  very  slightly  constricted;  median  compartment  broad,  slightly 
inflexed  at  the  ends,  slightly  expanded  in  the  middle ;  compartments 
at  either  side  nearly  linear ;  strieB  extremely  faint ;  marginal  striate 
band  narrow ;  stria)  costate,  not  reaching  the  margin,  nearly  parallel ; 
length  -0036,  breadth  -0011.     (Plate  33,  fig.  21.) 

Pinnularia  marginata,  O'Mcara,  Q.J.  M.S.,  1869,  p.  15,  PI.  xii., 
fig.  4. 

Arran  Islands;  Stomachs  of  Ascidians,  Broadhaven  Bay;  Sto- 
machs of  Asci(li£inB,  Koundstone  Bay,  Co.  Galway. 

Kavitvla  suhcinciay  (Schmidt).     Marine. 

Yalve  large,  slightly  constricted,  ends  somewhat  cuneate,  rounded ; 
median  compartment  broad,  infiexcd  at  the  ends,  slightly  constricted 
in  the  middle ;  compartments  on  either  side  broad,  unstriate ;  marginal 
striate  band  divided  into  two  equal  portions  by  a  longitudinal  sulcus ; 
strise  costate,  close,  parallel  in  the  middle,  slightly  radiate  towards  the 
ends;  length  '0042,  breadth  at  the  constriction  '0015;  greatest 
breadth,  -0016.      (Plato  33,  fig.  22.) 

Schmidt,  Biolog.  Unteisuch.  der  Nordsee.  Diat.,  p.  87.,  T.  xi.,  fig.  7. 

AntuL  Islands.  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Gal- 
way. 

Navieula  archerianny  N.  S.     Marine. 

Yalve  large,  slightly  constiicted ;  ends  somewhat  cuneate,  rounded ; 
median  compartment  broad,  io flexed  at  the  ends,  constricted  in  the 
middle ;  compartments  at  either  side  broad,  arcuate ;  marginal  stiiate 
band  narrow ;  stria)  costate,  parallel  in  the  middle,  radiate  towards  the 
ends;  length  '0026,  breadth  -0012;  at  constriction,  -0011.  (Plate 
33,  fig.  23.) 

O'Meara,  Q.  J.  M.  S.,  1874,  p.  260,  PL  vui.,  fig.  9.— Navieula  don- 


O'Mbara — Beport  on  the  Irish  Biatomacm,  399 

kinii,  Schmidt,  Atlas,  T.  zii.,  fig.  64.  This  species  is  at  first  view 
extremely  like  Navicula  donkiiiii ;  it  is,  however,  considerably  larger, 
the  8tri»  finer  and  closer,  and  valve  more  deeply  constricted. 

Arran  Islands ;  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Qal- 
way. 

Navicvla  ineurvatay  (Gregory).     Marine. 

Yalve  slightly  constricted;  median  compartment  tolerably  wide, 
slightly  inflexed  at  the  ends,  very  slightly  inflexed  in  the  middle; 
compartments  at  either  side  about  the  same  width  as  the  median, 
slightly  arcuate,  unstriate;  marginal  band  of  strise  narrow;  strisB 
nearly  parallel  throughout,  fine,  tolerably  close ;  indistinctly  punctate ; 
puncta  very  close;  length  '0028,  breadth  *0009;  at  constriction, 
-0008.     (Plate  33,  fig.  24.) 

Gregory,  a  J.M.  S.,  1856,  p.  44,  PI.  ▼.,  fig.  13.  In  this  figure 
the  marginal  band  of  striaB  is  represented  as  very  much  wider  than  it 
appears  to  be  in  any  of  the  very  numerous  specimens  I  have  met  with, 
and  also  the  compartments  on  either  side  of  the  median  line  are  much 
narrower ;  in  consequence  of  this,  I  was  induced  to  consider  the  form 
distinct  &om  that  of  Gregory,  and  named  it  Kavicula  pellucida, 
4i.  J.M.  S.,  1867,  p.  115,  PI.  v.,  fig.  3.  Ralfs,  in  Pritch.,  p.  893. 
Donkin,  N.  H.  Brit.  Diat.,  p.  49,  PL  vii.,  fig.  4.  This  figure  does  not 
<lescribe  the  incurved  ends  and  middle  of  the  median  compartment. 
Donkin  regards  the  species  as  =  to  Navicula  interrupta,  Grunow,  Ver- 
hand.  der  K.  K.  Zool.  Bot.  GeseU.,  Band  x.,  1860,  p.  531,  T.  iii.,  fig.  20. 
If  so,  Grunow' 8  figure  is  liable  to  the  same  remark  as  that  of  Gregory. 
— ^Navicula  splendida,  var.  incurvata,  BAb.  Fl.  Eur.  Alg.,  sect,  i., 
p.  204.  I  think  the  form  obviously  distinct  from  Kavicula  splen- 
dida. 

Arran  Islands;  Stomachs  of  Ascidians,  Broadhaven  Bay;  Sto- 
machs of  Ascidians,  Boundstone  Bay,  Co.  Galway.  Stomachs  of  Asci- 
dians, Co.  Clare. 

Navicula  muscat  (Gregory).    Marine. 

Yalve  small,  deeply  and  suddenly  constricted ;  ends  sharp ;  median 
<jompartment  relatively  broad,  inflexed  at  ends,  slightly  constricted  in 
the  middle;  compartments  at  either  side  narrow,  arcuate,  unstriate; 
marginal  band  of  striss  narrow,  obscurely  punctate,  extremely  short  in 
the  middle,  radiate  towards  the  ends;  length  '0012,  breadth  *0006; 
at  the  constriction,  *0004.     (Plate  33,  fig.  25.) 

Gregory,  Diat.  of  Clyde,  p.  479,  PI.  ix.,  fig.  6.  This  figure  by  no 
means  agrees  with  the  description  nor  the  measurements  of  the  text.' 
■So  that  it  is  not  at  all  to  be  wondered  at  that  Donkin  should  have  con- 
sidered it  identical  with  that  which  he  has  figured  as  Navicula  musca. 
Donkin' s  form  referred  to  was  properly  regarded  by  Schmidt  as  a  dis- 


400  Proceedings  of  the  Royal  Irish  Academy. 

tinot  species,  and  named  Navicula  donkinii,  the  name  which  I  had 
given  to  it  in  my  list  hefore  the  Atlas  had  come  under  my  notice. 
The  form  here  described  agrees  precisely  with  Gregory's  description  of 
Nayicula  musca,  which  may  readily  be  distinguif^ed  from  Navicnla 
donkinii,  by  its  much  deeper  constriction,  and  ^e  sharp  outline  at  the 
ends,  in  consequence  of  which  it  resembles  the  abdomen  of  a  fly; 
the  strie,  too,  in  this  are  punctate,  while  in  the  other  they  arc 
costate. 

Piles  of  wooden  bridge  on  Dollymount  Strand,  Co.  Dublin. 

Navicula  interruptay  (Kiitzing).     Marine. 

Valve  deeply  constricted;  lobes  suborbicular ;  median  compart- 
ment broad,  greatly  inflexed  at  the  ends,  considerably  constricted  in 
the  middle  ;  compartments  on  either  side  very  narrow,  bilunate, 
unstriate ;  marginal  band  of  striae  very  narrow  in  the  middle,  where 
the  strise  seem  to  fail,  but  tolerably  wide  in  the  middle  of  the  lobes ; 
strin  costate,  nearly  parallel  in  the  middle,  radiate  towards  the  ends ; 
length  -0023,  breadth,  0010  ;  at  constriction  -0007.   (Plate  33,  fig.  26.) 

Kutz.  Bac,  p.  100,  T.  xxix.,  fig.  93.  Ralfs,  in  Pritch.,  p.  894. 
Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  205.  Donkin,  N.  H.  Brit.  Diat.,  p.  47,. 
PI.  vii.,  fig.  2.  Schmidt,  Atlas,  T.  xii.,  fig.  2. — Navicula  didyma, 
Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  53,  PL  xvii.,  fig.  154a. 

Ballysodare,  Co.  Sligo.  Lough  Gill,  Co.  Kerry.  Arran  Islands ;. 
Stomachs  of  Ascidians,  Boundstone  Bay  ;  Stomachs  of  Ascidians^ 
Broadhaven  Bay,  Co.  Galway.     Seaweeds,  coast  of  Co.  Clare. 

Navietda  apis,  (£hr.)    Marine. 

Valve  deeply  constiicted,  ends  narrowed  and  rounded;  median 
compartment  broad,  with  well-defined  boundary  lines,  slightly  inflexed 
at  ends,  slightly  constricted  in  the  middle ;  compartments  at  cither 
side  unstriate,  narrow,  tapering  to  a  point  at  the  ends;  marginal 
band  of  strise  narrow  in  the  middle,  increasing  considerably,  and  then 
narrowing  towards  the  ends ;  striss  in  the  middle  apparently  costate, 
convergent  towards  the  ends,  radiate,  and  having  the  appearance  more 
of  fine  costflo  interrupted  by  close  longitudinal  sulci,  than  of  being 
moniliform;  length  -0038,  breadth  '0011;  breadth  at  the  constric- 
tion 0008.     (Plate  83,  fig.  27.) 

There  is  great  difficulty  in  identifying  the  species  so  named,  and 
with  some  hesitation  have  I  come  to  my  conclusion  on  the  subject. 
Kiitzing's  figure  of  Navicula  apis  is  shorter  and  stouter  than  the  pre- 
sent, 8ud  the  striss  are  so  indistinct  as  to  furnish  no  help.  Donkin's 
figure  in  outline  is  precisely  the  same  as  in  the  form  under  considera- 
tion; the  striae,  however,  are  represented  as  more  decidedly  punctate, 
and  the  compartments  on  either  side  of  the  median  one  are  distinctly^ 
striate.     In  the  present  case,  there  is  sometimes  an  appearance  of  stritD 


O'Meara — Report  on  the  Irish  Diatomacece.  401 

there,  but  with  precise  focuBing  they  disappear,  or,  if  they  appear  at 
all,  are  very  faint.  Schmidt's  figure  represents  the  species  as  more 
robust  than  mine,  but  the  compartments  on  either  side  of  the  median 
one  are  just  as  in  mine. 


Arran  Islands ;  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Oal- 
way. 

Navxoula  homhuSj  (Ehr.)    Marine. 

Valves  much  constricted,  lobes  much  inflated ;  median  compart- 
ment very  wide,  the  boundary  lines  strong,  and  having  the  edges 
milled,  greatly  curved  at  the  ends,  slightly  constricted  in  the  middle ; 
compartments  at  either  side  narrow ;  scarcely  striate,  or  if  striate,  the 
strise  very  faint;  marginal  band  of  strisB  very  wide;  striae  remote,  dis- 
tinctly moniliform,  the  beads  being  distant,  parallel  in  the  middle, 
more  and  more  radiate  towards  the  ends;  length  *0036,  breadth 
0016 ;  breadth  at  the  constriction  -0010.     (Plate  38,  fig.  28.) 

Balfs,  in  Pritch.,  p.  898,  who  attributes  the  species  to  Ehrenberg. 
Gregory,  Diat.  of  Clyde,  p.  484,  PL  ix.,  fig.  12.  Bab.  Fl.  Eur.  Alg., 
sect,  i,  p.  204.  Donkin,  N.  H.  Brit.  Diat.,  p.  50,  PI.  vii.,  fig.  7a. 
This  figure  fairly  represents  the  characters  of  the  species,  but  in  my 
specimens  the  consbiction  is  deeper,  and  the  compartments  at  either 
side  of  the  median  one  are  much  narrower.  Cleve,  Om  Svenska  och 
Iforska  Diat,  p.  226. 

Arran  Islands ;  Stomachs  of  Ascidians,  Broadhaven  Bay ;  Sto- 
machs of  Ascidians,  Boundstone  Bay,  Co.  Galway.  Ballysodare,  Co. 
Sligo.  Malahide,  Portmamock,  Co.  Dublin.  Bannow,  Co.  Wex- 
ford. Stomachs  of  Ascidians,  coast  of  Co.  Clare.  Stomachs  of  Ascidians, 
Belfast  Lough,  Co.  Antrim. 

Na/oieula  entomanf  (Ehr.)    Marine. 

Valves  not  so  deeply  constricted  as  in  Navicula  bombus ;  median 
compartment  narrow,  inflexed  at  the  ends,  slightly  constricted  in  the 
middle ;  compartments  at  either  side  narrow,  unstriate,  or  strise  T&ry 
obscure ;  marginal  band  of  striae  broad ;  striae  distinctly  moniliform, 
distant,  parallel  in  the  middle,  radiate  towards  the  ends;  length 
-0030,  breadth  '0012 ;  breadth  at  the  constriction  -0010. 

This  species  strongly  resembles  Navicula  bombus  in  the  character 
of  the  moniliform  striae  ;  the  constriction  is,  however,  not  so  deep,  nor 
are  the  lobes  so  much  expanded;  the  median  compartment  also  is 
much  narrower  in  this  species  than  it  is  in  the  other. 

Kiitz.  Bac,  p.  100,  T.  xxviii.,  fig.  74.  In  this  case,  the  figure  is 
very  obscure.  Kiitzing  attributes  the  species  to  Ehrenberg.  Balfs,  in 
Pritch.,  p.  893.  Donkin,  N.  H.  Brit.  Diat.,  p.  49,  PI.  vii.,  fig.  5. 
This  figure  represents  the  species  as  much  larger,  and  the  compart- 


402  Proceedings  of  the  Royal  Irish  Academy. 

ments  on  either  side  of  the  median  one  wider  than  they  appear  in  my 
specimens.  Schmidt,  Atlas  der  Diat.,  T.  xii.,  fig.  51.  In  outline, 
this  figure  exactly  represents  the  present  species ;  the  striation,  how- 
ever, seems  different. 

Arran  Islands  ;  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Gal- 
way. 

Navicula  didyma^  (Ehr.)     Marine. 

Yalres  slightly  constricted ;  median  compartment  wide,  inflexed 
at  the  ends,  greatly  constricted  in  the  middle ;  compartments  on  either 
side  very  narrow,  exhibiting  a  row  of  moniliform  dots  on  the  inner 
margin ;  marginal  striate  band  broad ;  strisB  radiate  throughout,  closely 
momliform;  length  about  *0030,  breadth  *0011 ;  breadth  at  the  con- 
striction -0010.  .  (Plate  33,  fig.  29.) 

Kiitz.  Bac,  p.  100,  T.  iv.,  fig.  7,  T.  xxviii.,  fig.  75.  In  the  former 
figure,  the  compartments  at  either  side  of  the  median  one  are  repre- 
sented as  much  wider  than  in  my  specimens ;  in  the  latter  figure  tho 
striae  are  represented  as  running  up  to  the  outer  margin  of  the  median 
compartment,  the  compartments  at  either  side  being  thus  wholly 
obliterated.  Kiitzing  attributes  the  species  to  Ehrenberg.  Wm.  Sm., 
B.  D.,  Vol.  i.,  p.  53,  ri.  xvii.,  fig.  54.  Ralfs,  in  Pritch.,  p.  893, 
PI.  xii.,  fig.  15.  Ralfs'  figure  of  the  species,  PI.  vii.,  fig.  61,  is  more 
like  Navicula  interrupta  than  Navicula  didyma.  Grunow,  Verhand. 
der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  530.  Cleve,  Om  Svenska 
och  NorskaDiat.,  p.  225.  Donkin,  N.  H.  Brit.  Diat.,  p.  51,  PI.  vii., 
fig.  8. 

The  form  described  by  Rabenhorst  as  Pinnularia  didyma,  Siissw. 
Diat.,  p.  46,  T.  vi.,  ^^,  26,  is  probably  the  same  as  the  present  spe- 
cies, but  if  80,  its  occuiTence  in  fresh  water  must  have  been  casual. 

Bannow,  River  Slancy,  at  Killurin,  Tacumshane,  Co.  Wexford. 
Malahide,  Portmamock,  Piles  of  wooden  bridge,  Dollymount  Strand, 
Co.  Dublin.  Lough  Foyle,  Co.  Deny.  Salt-marsh,  near  town  of 
Wicklow.  Kilkee,  Co.  Clare.  Arran  Islands  ;  Stomachs  of  Ascidians, 
Roundstone  Bay ;  Stomachs  of  Ascidians,  Broadhaven  Bay,  sea- 
weeds near  Westport,  Co.  Galway.  Stomachs  of  Ascidians,  Belfast 
Lough,  Co.  Antrim. 

Navicula  splendida^  (Gregory).     Marine. 

Valve  large,  deeply  constricted;  median  compartment  wide, 
greatly  inflexed  at  the  ends,  greatly  constricted  in  the  middle ;  com- 
partments at  either  side  narrow,  having  the  inner  edge  milled ;  mar- 
ginal band  of  striae  narrow  in  the  middle,  widening  in  a  graceful  curve 
towards  the  middle  of  the  lobe,  then  narrowing  towards  the  somewhat 
lanceolate  ends ;  stria)  convergent  in  the  middle,  radiate  towards  the 


O'Meara — Report  on  the  Lnsh  Diatomacece.  403 

ends,  moniliform,  the  beads  being  quadrangnlar ;  length  *0040, 
breadth  -0012;  breadth  at  the  constriction  0007.  (Plate  33,  fig.  30.) 
Gregory,  Q.  J.  M.  8.,  1866,  PL  v.,  fig.  14.  Ralfs,  in  Pritch., 
p.  893.  Rab.  FI.  Eur.  Alg.,  sect,  i.,  p.  204.— Navicula  entomon. 
Donkin,  N.  H.  Brit.  Diat.,  p.  49,  PL  vii.,  fig.  6.  The  outline  of  this 
form  greatly  resembles  that  of  Navicnla  incurvata,  which  Habenhorst 
makes  a  Tariety  of  this  species.  So  different,  however,  is  the  character 
of  the  striae,  that  they  cannot  properly  be  considered  as  nearly  related. 
The  present  form  differs  so  much,  both  in  outline  and  striation,  from 
Navicula  entomon,  that  it  ought  to  be  considered  a  very  distinct 
species. 

Arran  Islands,  Co.  Galway. 

Navieula  ffregoriiy  (O'Meara).     Marine. 

Yalves  considerably  constricted,  lobes  much  expanded,  median 
compartment  wide,  greatly  inflexed  at  the  ends,  slightly  constricted 
in  the  middle ;  central  nodule  large,  quadrangular,  with  three  short 
«pine-like  projections  at  each  side  ;  compartments  on  either  side  nar- 
row, attenuated  to  a  point  at  the  ends,  roundly  expanded  in  the  mid- 
dle; marginal  band  of  striae  wide;  strise  convergent  in  the  middle, 
radiate  towards  the  ends,  moniliform;  beads  large,  quadrangular; 
length  -0045,  breadth  -0028;  breadth  at  the  constriction  '0016. 
(Plate  33,  fig.  31.) 

Navicula  didyma,  var.  y.  Gregory,  Q.  J.  M.  S.,  1856,  p.  45, 
PL  v.,  fig.  16. 

Arran  Islands,  Stomachs  of  Ascidians,  Eoundstone  Bay,  Co. 
Galway. 

Navicida  mlUavMoniij  (Wm.  8m.)    Marine. 

Yalve  large ;  margin  incurved,  rather  than  constricted ;  median  com- 
partment wide,  infiexed  at  the  ends,  constricted  in  the  middle  ;  com- 
partments at  either  side  scarcely  so  wide  as  the  median  one,  narrowed 
to  a  point  at  the  ends,  greatly  expanded,  and  anglewise  in  the  mid- 
dle, striate ;  marginal  band  of  striss  wide ;  striae  slightly  convergent 
in  the  middle,  radiate  towards  the  ends,  moniliform;  beads  large, 
quadrangular ;  length  '0072,  breadth  '0029 ;  breadth  at  the  middle 
•0026.     (Plate  33,  fig.  32.) 

Navicula  didyma,  sporangial  var.  ?  Wm.  Sm.,  B.  D.,  Yol.  i., 
p.  53,  PL  xvii.,  fig.  154*. — Navicula  smithii,  Donkin,  N.  H.  Brit. 
Diat.,  p.  6,  PL  i.,  fig.  4.  This  form  on  first  view  would  appealr  to  b^ 
an  incurved  variety  of  Navicida  fusca,  which  it  resembles  much  more 
than  it  does  Navicula  smithii.  I  believe  it  is  only  necessary  to  see 
the  form,  which  is  extremely  rare,  in  order  to  be  convinced  that  it  is 
as  distinct  from  Navicula  didyma  as  it  is  from  Navicula  fusca.  Pro- 
fessor Smith  informs  us  that  the  species  came  under  his  observation 
in   a  collection  made  by  Professor  Williamson  in  the  Isle  of  Skye. 

Arran  Islands ;  Stomachs  of  Ascidians,  Bcuadstone  Bay,  Co.  Galway. 


404  Proceedings  of  the  Royal  Irish  Acadefny. 

N0/9ioula  incisa,  N.  S.    Marine. 

Valve  deeply  conatricted ;  median  compaxtment  narrow ;  inflexed 
at  enda,  slightly  contracted  in  the  middle ;  compartmenta  at  either 
aide  narrow,  atnate ;  atrie  faint ;  marginal  band  of  atriiB  narrow  in 
the  middle,  wide  towards  the  middle  of  the  lobes ;  strias  convergent 
in  the  middle,  nearly  parallel  for  some  distance,  and  slightly  nu^te 
towards  the  ends ;  costate,  divided  into  fonr  distinct  equal  biemda,  by 
three  deep  sulci,  which  lie  coDf ormably  with  the  outer  margin ;  the 
ooatae  in  each  band  appear  slightly  curved;  length  -0035.  breadth 
'0015  ;  breadth  at  the  constriction  *0010.     (Plate  83,  fig.  33.) 

This  form  somewhat  resembles  that  figured  by  Schmidt,  Atlas  der 
Diat.,  T.  xii.,  figs.  21  to  24,  without  a  name,  and  which  he  thinka 
atanda  between  Kavicula  apis  and  Kavicula  splendida,  but  I  doubt 
ita  identity  with  either. 

Arran  Islands,  Co.  Oalway. 


Navieula  erahro,  (Ehr.)    Marine. 

Valves  large,  slightly  constricted ;  median  compartment  narrow^ 
slightly  inflexed  at  ends,  constricted  in  the  middle ;  compartments  on 
either  side  wider,  gently  tapering  towards  the  ends ;  striate,  the  enda 
of  the  striflB  appearing  as  large  puncta  on  the  elevated  margin  of  the 
inner  edge;  marginal  striate  band  wide;  strisd  convergent  in  the 
middle,  radiate  towards  the  ends ;  costate ;  length  '0073,  breadth 
'0021 ;  breadth  at  constriction  '0015. 

Wm.  8m.,  B.  D.,  Vol.  ii.,  p.  94.  Donkin,  N.  H.  Brit.  Diat.^ 
p.  46,  PL  vii.,  fig.  la.  Balfs,  in  Pritch.,  p.  894.  Bab.  Fl.  Eur.  Alg., 
sect,  i.,  p.  204. — Diploncis  crabro,  Ehr.,  Mic,  T.  xix.,  fig.  29. 
— Navicula  pandura,  De  Brebisson,  Diat.  du  Littoral  de  Cherbourg^ 
p.  16,  PI.  i.,  fig.  4. — Pinnularia  pandura,  var.  elongata,  Gregory,  Diat. 
of  Clyde,  p.  489,  PL  ix.,  fig.  22.  Though  Kalfs  and  Eabenhorst  seem 
to  regard  this  form  as  distinct  from  Navicula  pandura,  I  am  inclined 
to  think  with  Donkin,  that  there  is  no  distinction  between  them. 
Smith  describes  the  strise  as  obscurely  moniliform ;  but  all  the  figures  I 
have  seen  represent  the  strise  as  distinctly  costate,  and  such  I  consider 
is  their  normal  character.  Donkin's  figure  represents  the  compart- 
ments at  either  side  of  the  median  compartment  as  unstriate,  except 
on  the  inner  edge,  where  there  is  a  row  of  large  bead-like  detached 
puncta.  In  all  the  specimens  I  have  seen,  the  costse  in  this  portion, 
though  of  a  fainter  colour,  are  clearly  traceable  all  through;  the 
large  puncta  described  by  Donkin  being  simply  the  ends  standing  out 
distinctly  on  an  elevated  ridge. 

Arran  Islands;  Stomachs  of  Ascidians,  Boundstone  Bay,  Co. 
Chdway. 


O'Meara — Bepart  on  the  Irish  Diatomac€(B.  405 

Var.  intermedia^  (O'Meara).     Marine. 

Yalve  considerably  smaller  than  that  of  the  typical  form;  the 
lobes  are  more  expanded ;  the  ends  of  the  costse  on  the  inner  edge  of 
the  compartments  on  either  side  of  the  median  one  are  longer,  the 
lidge  seeming  to  be  in  this  case  wider,  and  not  so  much  elevated. 

This  is,  perhaps,  identical  with  Navicula  crabro,  Grunow,  Ver- 
hand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  524,  T.  v., 
fig.  21,  and  with  Kavicnla  nitida,  Gregory,  Q.  J.  M.  S.,  1856,  p.  44^ 
PL  v.,  fig.  12. 

Broadhaven  Bay.    Koundstone  Bay. 

Var.  denticulatay  (O'Meara).    Marine. 

Yalve  very  much  smaller  than  the  preceding  variety,  not  so  much 
constricted,  the  ends  of  the  striaB  appearing  on  the  inner  edge  of  the 
compartments  on  either  side  of  the  median  one  being  of  the  same 
breadth,  or  nearly  so,  as  that  of  the  costae  of  the  marginal  band  of  striae, 
which  are  very  narrow.     (Plate  33,  fig.  34.) 

'  JSTavicula  denticulata,  O'Meara,  Q.  J.  M.  S.,  1867,  p.  115,  PI.  v., 
fig.  2.  In  the  description  at  first  given  of  this  form  it  would  appear  as 
if  the  space  between  the  two  bands  of  costse  were  unstriate ;  but  upon 
more  close  examination,  with  better  illumination  than  I  then  possessed, 
I  have  satisfied  myself  that  the  costsB  pervade  the  interspace.  They 
are  indeed  very  indistinct,  but  stiU  traceable. 

Arran  Islands ;  Stomachs  of  Ascidians,  Broadhaven  Bay ;  Stomachs 
of  Ascidians,  Boundstone  Bay,  Co.  Galway. 

Navictda  pJUzeriana^  N.  S.     Marine. 

Valve  small,  slightly  constricted ;  median  compartment  very  nar- 
row, lanceolate ;  compartments  at  either  side  become  wider  in  middle 
than  at  ends ;  striate ;  marginal  striate  band  relatively  wide ;  striae^ 
linear,  close,  convergent  in  the  middle,  thence  finer,  and  nearly  paral- 
lel; length  -0017,  breadth  -0005;  breadth  at  constriction  -0004. 
(Plate  83,  fig.  35.) 

This  form  was  a  considerable  time  ago  exhibited  by  me  among^ 
other  interesting  species  collected  by  Mr.  Mozely,  H.  M.  S.  Challenger, 
on  the  coast  of  Patagonia.  It  is  identical  with  a  specimen  from  Val- 
paraiso, figured  as  Navicula  divergens  by  Schmidt,  Atlas  der  Diat., 
T,  xii.,  fig.  53;  but  as  my  designation  has  the  priority  of  publication,, 
it  has  a  right  to  stand. 

Stomachs  of  AECidians,  coast  of  Co.  Clare. 

Navicula  viehenii,  N.  S.     Marine. 

Valve  very  large,  deeply  constricted ;  median  compartment  linear, 
wide ;  compartments  on  either  side  wide,  unstriate,  bilunate  on  tho 
outer  margin ;  marginal  striate  band  narrow  in  the  middle,  widening 
towards  the  broadest  part  of  the  heart-shaped  lobes,  and  thence  decreas- 
ing in  width  towards  the  rounded  ends ;  strias  costate,  nearly  parallel 


406  Proceedings  of  the  Royal  Irish  Academy. 

in  the  middle,  convergent  towards  the  ends ;  a  strongly  developed  sab- 
marginal,  longitudinal  sulcns  appears  conformable  with  the  onter 
margin  of  the  valve ;  length  '0055,  breadth  '0020 ;  breadth  at  the  con- 
striction-0011.     (Plate  33,  fig.  86.^ 

This  very  striking  form  was  exnibited  by  me  some  years  ago,  at  a 
meeting  of  the  Dublin  Microscopical  Club,  at  the  house  of  Mjt.  Henry 
Tickers,  with  whose  name  it  is  associated. 

Arran  Islands ;  Stomachs  of  Ascidians,  Boundstone  Bay,  Co.  Gal- 
way. 


(1.)    Peritriata,     Stria  reaching  the  median  line, 
j  Directa.     Stria  parallel. 

Naticula  directa^  (Wm.  Sm.)    Harine. 

Valve  narrow,  lanceolate ;  median  line  distinct;  strisB  finely  cos- 
tate;  length  -0025,  breadth  '0003.     (Plate  84,  fig.  4.) 

llulfs,  in  Pritch.,  p.  906.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  224.— Pinnularia  directa,  Wm.  Sm.,  B.D.,  Vol.  i.,  p.  66,  Pl.xviii., 
fig.  172.     Hab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  217. 

Malahide,  Co.  Dublin.     Stomachs  of  AscidiauR,  Co.  Clare. 

Navicida  lanceolata,  (Kiitz.)    Fresh  water. 

Valve  lanceolate;  striae  punctate;  length  '0016,  breadth  '0004. 

Kiitz.  Bac.,  p.  94,  T.  xxviii.,  fig.  38 ;  T.  xxx.,  fig.  48.  Neither 
of  these  figures  indicates  the  character  of  the  striae ;  it  is  therefore 
impossible  to  identify  Kiitzing's  species  with  certainty.  "Wm.  Sm., 
B.  D.,  Vol.  i.,  p.  46,  suppl.  PL  xxxi.,  fig.  272.  BAb.  Fl.  Eur.  Alg., 
sect,  i.,  p.  171.  This  author  attributes  the  species  to  Wm.  SmiUi, 
who  has  described  it  so  that  it  can  be  easily  recognised,  and  regards  it 
as  distinct  from  that  so  named  by  £iitzing. 

River  Bann,  near  Colerainc,  Co.  Derry.  Eilcool,  Co.  Wicklow. 
Adregoolc,  Co.  Galway. 

Navicula  exiliSf  (Kiitz.)     Fresh  water. 

Valve  small,  narrow,  elliptical ;  ends  produced  and  slightly  capi- 
tate ;  striae  obscure;  length  -0013,  breadth  '0003.     (Plate  34,  fig.  2.) 

Kiitz.  Bac,  p.  95,  T.  iv.,  fig,  6.  This  figure  does  not  represent 
the  striae.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x., 
1860,  p.  553,  T.  iv.,  fig.  30.     Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  198. 

Lough  Mask,  near  Touimakeady,  Co.  Mayo. 


O'Mbaba — Beport  on  the  Irish  Diatomacete.  407 

f  f  Radiosa,    Stria  more  &r  leas  distinctly  radiate, 

Navieula  radiosa,  (Kiitz.)    Presli  water. 

Valye  lanceolate,  obtuse ;  striaa  strongly  costate ;  convergent  in 
middle,  radiate  towards  the  ends ;  length  about  *0020,  breadth  about 
•0005.     (Plate  34,  fig.  3.) 

Kiitz.  Bac.,  p.  91,  T.  ir.,  fig.  23.  Ralfs,  in  Pritch.,  p.  905. 
Grunow,  Yerhand.  derK.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  Cleve, 
Om  Svenska  och  Norska  Diat.,  p.  225,  Lagerstedt,  Sotv.  Diat.  fran 
Spitzbergen  och  Beeren  Eiland,  p.  25. — Pinnularia  radiosa,  Wm. 
Sm.  B.  D.,  Vol.  i.,  p.  56,  PI.  xyiii.,  fig.  173.  Rab.  Fl.  Eur.,  Alg., 
sect,  i.,  p.  214. 

Pool,  Glengariff,  Co.  Cork.  Lower  Lake,  Killamey,  Co.  Kerry. 
Stream  Crossdoney,  Co.  Cavan.  River  Dodder,  Bohemabreena,  Glenas- 
mole,  Killakee,  Co.  Dublin.     Lake  near  Castlcwellan,  Co.  Down. 

Navietila gracilis^  (Ehr.)    Freshwater. 

Valve  lanceolate,  attenuated  towards  the  ends,  which  are  obviously 
produced ;  striie  costate,  convergent  in  the  middle,  radiate  towards 
the  ends ;  length  about  -0022,  breadth  about  -0005.    (Plate  34,  fig.  4.) 

Kiitz.,  Bac.,  p.  91,  T.  iii.,  fig.  48,  T.  xxx.,  fig.  57,  who  regards 
the  species  described  by  him  as  identical  with  Navicula  gracilis,  Ehren- 
berg,  Lifus.,  1838,  p.  176,  T.  xiii.,  fig.  2.  Smith  is  doubtful  as  to 
the  identity  of  the  form  described  and  figured  by  him  with  that  of 
Kiitzing  just  referred  to  and  comparison  of  the  figures  of  Kiitzing 
with  specimens  of  the  form,  so  accurately  delineated  by  Smith  will 
impress  something  more  than  doubt  upon  the  observer's  mind.  Balf  s, 
in  Pritch.,  p.  906.  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell., 
Band  x.,  1860,  p.  526,  T.  iv.,  fig.  27.  The  species  is  broader,  moro 
attenuated  at  the  ends,  than  this  figure  represents  it.  Schumann,  Diat., 
der  Hohen  Tatra,  p.  69.  Ilab.  Fl.  Eur.,  Alg.,  sect,  i.,  p.  174.— Pin- 
nularia gracilis,  Wm.  Smith,  B.  D.,  Vol.  i.,  p.  57,  PI.  xviii.,  fig. 
174. 

Drumoughty  Lough,  near  Kenmare,  Co.  Kerry,  Stream,  Bellarena, 
Co.  Deny.  Stream  near  Crossdoney,  Co.  Cavan.  Stream,  Killiney, 
Stream,  BaUybrack,  Co.  DubUn. 

Navicfda  acuta,  (Wm.  Smith).     Fresh  water. 

Valve,  narrow,  lanceolate ;  ends  acute ;  striaa  costate,  convergent 
in  the  middle,  radiate  towards  the  ends ;  length  '0046,  breadth  *0005. 
(Plate  34,  fig.  5.) 

Pinnularia  acuta,  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  56,  PI.  xviii., 
fig.  171. — I^avicula  radiosa,  var.  acuta.  Grunow,  Verhand.  der  K. 
K.  Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  526.     There  is  a  form  described 


408  Proceedings  of  the  Royal  Irish  Academy. 

and  figured  by  Kiitzing  nnder  the  name  of  Nayicula  acuta,  the^  de- 
tails of  which  are  so  indistinct  that  identification  would  be  impossible, 
but  the  outline  of  the  valve  is  such  as  to  make  it  certain  that  it  is 
distinct  from  the  present  form.     Kiitz.  Bac.,  p.  93,  T.  iii.,  fig.  69. 

In  a  fossil  state,  it  occurs  abundantly  in  the  Lough  Moume  de- 
posit. In  a  living  state,  I  have  found  it  in  the  following  localities : 
River  Erne,  near  Crossdoney,  Co.  Cavan.  Lower  Lake,  Killamey, 
Caumlough  near  Tralee,  Co.  Kerry.  Biver  Dodder,  Fond  in  Botanic 
Gardens  of  Trinity  College,  Co.  Dublin.     Kilcool,  Co.  "Wicklow. 

Navietda  actdituetda,  (Gregory).     Marine. 

Valve  narrow,  lanceolate,  with  acute  ends.  Strie  costate,  slightly 
radiate  throughout;  length  '0040,  breadth  '0005. 

Ralfs,  in  Pritch.,  p.  906. — Pinnularia  acutiuscula,  Gregory,  Q.  J. 
M.  8.  1856,  Trans.,  p.  48,  PL  v.,  fig.  21.  Rab.  FL  Eur.  Alg.,  sect,  i., 
p.  218. 

Stomachs  of  Ascidians,  seacoast,  Co.  Clare. 

Navieula  peregrina^  (Ehr.)    Marine  or  brackish  water. 

Valves  broadly  lanceolate,  ends  obtuse.  Strise  costate,  sub-distant, 
radiate;  length  -0046,  breadth   0010.     (Plate  34,  fig.  6.) 

Kiitz.  Bac,  p.  97,  T.  xxviii.,  fig.  52.  The  form  was  considered 
by  Kiitzing  to  be  identical  with  Pinnularia  peregrina  of  Ehrenberg. 
Ralfs,  in  Pritch.,  p.  906.  Cleve,  Om  Svenska  och  Norska  Diat., 
p.  225,  Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x., 
18C0,  p.  523.— Pinnularia  peregrina,  Wm.  Sm.,  B.  D.,  Vol.  i.,p.56, 
PI.  xviii.,  fig.  170.     Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  213. 

Salt  ditch  near  the  Town  of  Wexford,  River  Slaney,  near  Killuiin, 
Tacumshane,  Co.  Wexford.  Bellarena,  mouth  of  the  River  Roe,  Co. 
Dcrry.  Rostrevor,  Co.  Down.  Breaches  near  Newcastle,  Co. 
Wicklow.  Kilkee,  Co.  Clare.  Lough  Gill,  Co.  Kerry.  Howth,  Co. 
Dublin.  Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway.  A 
small  variety  of  this  species  occurred  from  stomachs  of  Ascidians 
Belfast  Lough,  Co.  Antrim. 

Navicula  tostereti^  (Grunow).     Marine. 

Vulve,  large  lanceolate  with  sharp  ends.  Striae  strongly  costate, 
sub-distant,  radiate ;  length  -0056,  breadth  '0002.     (Plate  34,  ^^,  7.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  528,  T.  iv.,  fig.  23.  The  locality  in  which  this  form  was  found  by 
Grunow  was  the  Adriatic  Sea,  from  a  depth  of  from  two  to  four 
fathoms.  I  know  of  no  other  locality  in  which  the  species  has  been 
discovered  save  that  specified  below. — Pinntdaria  zostereti,  Rab.  H. 
Eur.  Alg.,  sect,  i.,  p.  218. 

Stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 


O'Meara — Eeport  an  the  Irish  Liatomacece.  409 

Navteida  eleviatM,  N.  S.     Marine. 

Valve  narrow,  elliptical.  Striae  strongly  costate,  convergent, 
ronnded,  and  sab-distant  in  the  middle,  radiate,  linear,  and  closer 
towards  the  ends.  Two  very  short  costse  are  interposed  in  the  middle 
between  the  next  which  run  to  the  median  Ime;  length  '0034 
breadth  -0008.     (Plate  34,  fig.  8.) 

From  stomachs  of  Ascidians,  Broadhaven  Bay,  Co.  Galway. 

Navieula  digiUhraiiataf  (Gregory).     Eresh  water. 

Yalve  elliptical,  with  obtuse  ends.  Strise  costate,  convergent,  and 
distant  in  the  middle,  radiate  towards  the  ends ;  length  '0028,  breadth 
'0008.     (Plate  34,  fig.  9.) 

Ralfs,  in  Pritch.,  p.  904. — Pinnularia  digito-radiata,  Gregory,  Q. 
J.  M.  8. 1856,  p.  9,  PI.  i.,  fig.  32.  Eab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  215. 

Bowen's  Court,  Co.  Cork.  Biver  Slaney,  near  Killurin,  Co.  Wex- 
ford, Lower  Lake,  Killamey.  Caumlough,  near  Tralee,  Co. 
Kerry.  River  Barrow,  near  Clonegal,  Co.  Carlow.  Ditch  near  Kil- 
cool,  Co.  Wicklow. 


Na/vieula  ergademis,  (Gregory).    Marine. 

Yalve  linear,  elliptical,  ends  obtuse,  rounded.  Striss  costate,  con- 
vergent in  the  middle,  radiate  towards  tiie  ends;  length  '0026,  breadth 
-0006.     (Plato  34,  fig.  10.) 

Kalfs,  in  Pritch.,  p.  907. — ^Pinnularia  ergadensis,  Gregory,  Q.  J. 
M.  S.  1856,  PL  v.,  fig.  22.     Bab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  215. 

Portmamock,  Malahide,  Co.  Dublin.  Lough  Gill,  Co.  Kerry. 
Salt  ditches  near  the  Town  of  Galway. 


Nanieula  eyprinui,  (Ehr.)    Marine. 

Yalve  rhombo-lanceolate,  ends  somewhat  cuneate.  StrisB  costate, 
convergent  in  the  middle,  radiate  towards  the  ends ;  length  '0025, 
breadth  -0007.     (Plate  34,  fig.  11.) 

Kiitz.  Bac.,  p.  99,  T.  xxix.,  fig.  35.  The  species  is  here  ascribed 
to  Ehrenberg.  The  figure,  it  must  be  observed,  is  very  inadequate  to 
describe  the  species,  i^e  ends  being  rounded  instead  of  cuneate,  and 
the  striae  parallel  instead  of  being  as  above  described. — Pinnularia 
cyprinus,  Wm.  Sm.,  B.  D.  Yol.  i.,  p.  57,  PI.  xviii.,  fig.  176.  Eab. 
Fl.  Eur.  Alg.,  sect,  i.,  p.  215. 

Bannow,  Biver  Slaney,  near  Killurin,  Co.  Wexford.  Lough  Foyle. 
Mouth  of  River  Roe,  Co.  Deny.  Seaweeds  near  Town  of  Wicklow. 
Malahide,  Portmamock,  Dalkey,  Co.  Dublin.     Kilkee,  Co.  Clare. 


410  Proceedings  of  Vie  Royal  Irhh  Academy, 

Navteula  ^alvayetuiSf  N.  8.     Marine. 

Yalve  oblong,  elliptical,  ends  narrowed  and  rounded.  StriiB  cos- 
tare,  radiate;  length  0024,  breadth  -0005.     (Plate  84,  fig.  12.) 

8alt  marsh  near  town  of  Galwaj ;  Stomachs  of  Ascidians,  Broad- 
haven  Bay,  Co.  Galway. 

Navicula  Solaris,  (Gregory).     Marine. 

Valve  elliptical,  with  obtuse  rounded  ends.  Strite  fine,  linear, 
convergent  in  the  middle,  and  very  distinct,  radiate  towards  the  ends 
and  less  distinct.     (Plate  34,  fig.  13.) 

Gregory,  Q.  J.  M.  S.  1856,  Trans.,  p.  43,  PI.  v.,  fig.  10.  This 
figure  represents  the  stria;  as  shortened  in  the  middle  so  as  to  leave  a 
blank  space  round  the  central  nodule.  And  such  is  the  appearance 
presented  by  the  specimens  that  have  come  under  my  notice ;  but 
when  well  focused  the  blank  space  disappears,  and  the  s^sb  are  found 
to  reach  the  median  line.  Kalfs,  in  Pritch.,  p.  904.  Kab.  Fl.  Eur. 
Alg.,  sect,  i.,  p.  181. 

Ballarena,  Co.  Derry.  Adregoole,  Co.  Galway.  Malahide,  Co. 
Dublin. 

Navicula  viridula,  (Kiitz.  ?)     Fresh  water. 

Valve  elliptical,  lanceolate,  sometimes  slightly  produced.  Striie 
fine,  linear,  convergent  in  the  middle,  radiate  towards  the  ends; 
length  -0016,  breadth  -0005.     (Plate  34,  fig.  14.) 

Kutz.,  Bac,  p.  91,  T.  xxx.,  ^g.  47 ;  T.  iv.,  figs.  10  and  15.  The 
only  one  of  these  figures  which  at  all  resembles  the  present  form  is 
the  last.  Ralfs,  in  Pritch.,  p.  905.  Cleve,  Om  Svcnska  och  Norska 
Diat.,  p.  225.  Lageratcdt,  Sotv.  I)iat.  fran  Spetsbergen  och  Beeren 
Eiland,  p.  25. — Pinnularia  viridula,  AVm.  Sm.,  B.  D.,  Vol.  i.,  p.  67, 
PI.  xviii.,  fig.  175.  The  description  is  accurate,  but  the  figure 
represents  the  costa;  as  greatly  coarser  than  they  arc  in  reality.  The 
effect  is  to  make  this  species  appear  scarcely  to  differ  fi-om  Pinnularia 
gracilis.  Lagerstcdt  indeed  remarks,  "  I  have  considered  it  right  to 
unite  under  the  above  name  (Navicula  viridula)  the  two  species  of 
Smith,  Pinnularia  viridula,  and  Pinnularia  gracilis,"  p.  25.  The 
stria;,  however,  in  the  former,  are  extremely  fine,  whereas  in  the 
latter  they  arc  very  coarse.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  214.  I 
think  it  not  unlikely  that  this  form  is  identical  with  that  which 
Grunow  has  described  as  Navicula  rhyncocephala,  var.  brevis. 
Verhand.  der  K.  K.  Zool.  Bot.  GeselL,  Band  x.,  1860,  p.  629,  T.  iv., 
fig.  Sic, 

Camolin,  Co.  Wexford.  Lough  Gill,  Co.  Kerry.  Eillakee, 
Stream  near  Clontarf,  Co.  Dublin  .Ditch  near  town  of  Sligo.  Well, 
Strokestown,  Co.  Roscommon. 


O'Meaba — Rqpori  an  the  Irish  DiatomacetB.  411 

Navieula  heuJUri^  (Omnow).    iFresh  water. 

Yalve  yery  fonall ;  lanceolate  \  central  nodule  large.  Si  rise  fine ; 
linear,  radiate ;  length  about  '0009,  breadth  about  *0003.  (Plate 
34.  fig.  15.) 

Gmnow,  Yerhand.  der  K.  K.  Zool.  Bot.  GeseU.,  Band  x.,  1860, 

L528,  T.  iii.,  fig.  32.     Schumann,  Diat.  der  Hohen  Tatra.,  p.  68. 
b.  Fl.  Eur.  Alg.,  sect,  i.,  p.  214. 

Lough  Gill,  Co.  Kerry.    Powerscourt,  Co.  "Wicklow. 

KavietdaforiiSf  (Gregory).    Marine. 

Yalve  small ;  broadly  lanceolate ;  rounded  at  ends.  Stris  costate, 
convergent  in  the  middle,  radiate  towards  the  ends ;  on  front  view, 
fnistule  slightly  constricted,  with  the  angles  slightly  rounded ;  length 
•0017,  breadth  0006. 

Kalfs,  in  Pritch.,  p.  905.  Donkin,  N.  H.  Brit.  Diat.,  p.  57, 
PL  viii.,  fig.  8i — ^Pinnularia  fortis,  Gregory,  Q.  J.  M.  S.,  Trans., 
1856,  p.  47,  PI.  v.,  fig.  19.    Eab.  PL  Eur.  Alg.,  sect.  L,  p.  216. 

Lough  Gill,  Co.  Kerry.  Arran  Islands,  Co.  Galway.  Malahide, 
Co.  Dublin. 

Kavicuia  northumhrieaj  (Donkin).    Marine. 

Yalve  narrow,  lanceolate;  ends  acute.  StrisQ  linear,  convergent  in 
middle,  where  they  are  strongly  marked;  length  '0019,  breadth 
•0004.  Prustule  on  front  view  slightly  constricted.  (Plate  34, 
fig.  16.) 

Donkin,  Q.  J.  M.  S.,  1861,  p.  9,  PL  i.,  fig.  5 ;  N.  H.  Brit.  Diat., 
p.  54,  PL  viii.,  fig.  1.    Bab.  PL  Eur.  Alg.,  sect,  i.,  p.  175. 

Bannow,  Co.  Wexford.    Salt  ditches  near  the  town  of  Galway. 

Navieula  arefiaria,  (Donkin).    Marine. 

Yalve  lanceolate,  narrow;  ends  acute,  produced  and  slightly 
constricted.  Striae  costate,  convergent;  length  '0019,  breadth  '0004. 
Prustule  on  front  view  very  slightly  constricted.     (Plate  34,  fig.  17.) 

Donkin,  Q.  J.  M.  S.,  1861,  p.  10,  PL  i.,  fig.  9;  N.  H.  Brit.  Diat., 
p.  56,  PL  viii,  fig.  6.    Eab.  Fl.  Eur.  Alg.,  sect,  i,  p.  177. 

Portmamock,  Co.  Dublin. 

Ifavieula  tnJUxa,  (Gregory).    Marine. 

Yalve  lanceolate;  slightly  depressed  at  the  extremities.  Strifld 
costate,  convergent;  length  '0018,  breadth  -0004.  (Plate  34 
fig.  18.) 

Balfs,  in  Pritch.,  p.  905.    Donkin,  N.  H.  Brit.  Diat.,  p.  54, 

&.  I.  A.  PBOC.,  SIB.  U.,  VOL«  U.,  8CIJ0CS«  2  X 


412  Proceedings  of  the  Royal  Irish  Academy. 

PL  viii.,  fig.  2.— Pinnnlaria  infleza,  Gregory,  Q.  J.  IC.  S.,  1856, 
Trans.,  p.  48,  PI.  v.,  fig.  20.  Rab.  Fl.  Eur.  Alg.,  sect,  i.,  p.  218. 
The  depression  of  the  valye  at  the  ends  is  marked  by  a  well-defined 
line  which  renders  the  species  easy  of  identification. 

Ballysodare,  Co.  SUgo.  Lough  Oill,  Co.  Kerry.  Malahide,  Co. 
Dublin. 

KanteuJa  hungariea,  (Orunow).    Fresh  water. 

Yalye  small,  oblong ;  elliptical,  ends  rounded.  StrisB  subdistant, 
strongly  costate,  radiate ;  central  nodule  large ;  length  *0009,  brradth 
•0045.     (Plate  34,  fig.  19.) 

Orunow,  Yerhand.  der  E.  E.  Zool.  Bot.  Oesell.,  Band  z.,  1860, 
p.  539,  T.  iii.,  fig.  30.  Schumann,  Diat.  der  Hohen  Tatra,  p.  76.  Bab. 
rl.  Eur.  Alg.,  sect,  i.,  p.  190. 

Lough  Gill,  Co.  Kerry.  Ditch  near  town  of  Sligo.  Lough  Mask, 
near  Tourmakeady,  Co.  Mayo. 

Ifavietda  earassiuij  (Ehr.)    Fresh  water. 

Yalyes  small,  broidly  elliptical;  ends  broadly  and  shortly  pro- 
duced. Strie  costate ;  nuiiate ;  length  '0007,  breadth  -0003.  (Plate 
34,  fig.  20.) 

Kiitz.  Bac.,  p.  95,  T.  zxviii.,  fig.  67.  The  description  and  figure 
represent  the  yalve  as  unstriate,  but  the  striaa  are  quite  obyious. 
Orunow,  Yerhand.  der  K.  K.  Zool.  Bot.  Oesell.,  Band  z.,  p.  537, 
T.  iii.,  fig.  31,  and  T.  iv.,  fig.  11.  Ralfs,  in  Pritch.,  p.  900. 
Donkin,  N.  H.  Brit.  Diat.,  p.  20,  PL  iii.,  fig.  7.  It  is  more  than 
doubtful  if  the  form  described  by  Donkin  as  Nayicula  carassius 
belongs  to  this  species.  The  figure  represents  the  form  as  yery  much 
longer,  the  ends  finer  and  more  produced,  than  is  the  case  in  Nayicula 
carassius ;  the  strisB  too,  are  described  as  granular,  the  strise  in  Nayicula 
carassius  are  linear.  Donkin  regards  the  species  as  identical  with 
Navicula  lacustris,  Oregory,  Q.J.M.  8.,  1856,  p.  6,  PI.  i.,  fig.  23b., 
but  the  true  Kayicula  carassius  is  broadly  elliptical,  and  not  linear, 
as  the  former  is  represented  to  be.  Schumann,  Diat  der  Hohen 
Tatra,  p.  68. 

Olenchree,  Kilcool,  Co.  Wicklow.  Kilcock,  Royal  Canal,  Enfield, 
Co.  Kildare.  Dundrum,  Co.  Dublin.  Killeshm,  Queen's  Co.  Caum 
Lough,  near  Tralee,  Arraglen,  Co.  Kerry. 

Naoieula  mutica,  (Kiitz.)    Fresh  or  brackish  water. 

Yalye  small,  broadly  elliptical.  Striee  punctate,  radiate ;  length 
•0005,  breadth  -0003.     (Plate  34,  fig.  21.) 

Kiitz.  Bac,  p.  95,  T.  iii.,  fig.  32,  who  found  the  form  in  rain 
pools  mized  witii  salt  water.    Orunow,  Yerhand.  der  K.  K.  Zool. 


O^Mbaba— 2fc?por^  on  the  Irish  DiatomaoecB.  413 

Bot.  Oefiell.,  Band  z.,  p.  538,  T.  y.,  fig.  16,  who  found  the  species  in 
freshwater  as  well  as  in  brackish.  Balfs,  in  Pritch.,  p.  905.  Schu- 
mann, Diat.  der  Hohen  Tatra,  p.  69.  Bab.  Fl.  Eur.  Alg.,  sect,  i., 
p.  185.  It  is  not  improbable  that  this  species  is  identical  with  the 
form  described  by  Gregory  as  Navicula  lepida,  yar.  B.  ?  Q.  J.  M.  S., 
1856,  p.  7,  PI.  i.,  fig.  25,  B. 

Bannow,  Co.  "Wexford.  Lough  Gill,  Co.  Kerry.  In  these,  fresh 
water  forms  and  marine  were  mingled.  Glencluree,  Killakee,  Co. 
Dublin.  Lough  Mask,  near  Tourmakeady,  Co.  Mayo.  The  three  last- 
named  localities  were  wholly  free  from  marine  influences.  Hence  I 
consider  that  though  the  form  has  been  found  in  brackish  water,  it  is 
essentially  a  fresh  water  species. 

Navicula  semen,  (Ehr.)    Eresh  water. 

Yalye  linear,  dliptical,  broad ;  ends  broadly  and  shortly  produced. 
Stria  costate;  conyergent  in  middle,  radiate  towards  ends;  length 
•0018,  breadth  -0008.    rPlate  34,  fig.  22.) 

Kiitz.  Bac.,  p.  99,  T.  zxyiii.,  fig.  49,  who  attributes  the  species 
to  Ehrenberg.  Wm.  Sm.,  B.  D.,  Vol.  i.,  p.  50,  PL  xvi.,  fig.  141.  Hei- 
berg,  De  Danske  Diat.,  p.  82.  Balfs,  in  Pritch.,  p.  900.  Donkin, 
X.  H.  Brit.  Diat.,  p.  21.  PI.  iii.,  fig.  8.  Schumann,  Diat.  der  Hohen 
Tatra,  p.  68. 

Stream,  Bellarena,  Co.  Derry.  Lough  Moume  deposit,  Co.  Antrim, 

Nanieula  humHis,  (Donkin).    Fresh  water. 

Yalye  small,  inflated  in  the  middle,  with  broad  capitate  ends.  Striss 
oostate,  coarse,  subdistant,  radiate;  central  nodule  large ;  length  '0010, 
breadth  '0003.  On  front  yiew,  frustule  quadrangular,  slightly  con- 
stricted in  the  middle ;  costsd  diyergent,  leaying  a  considerable  space 
about  the  central  nodule,  which  latter  appears  yery  highly  deyeloped. 

Donkin,  N.  H.  Brit.  Diat.,  p.  67,  PI.  x.,  fig.  7.  Donkin  considers 
this  form  identical  with  Nayicula  inflAta,  yar.  Gregory,  Q.  J.  M.  S., 
1855,  PL  ii.,flg.  20  c. 

Lough  GiU,  Co.  Kerry.  Lough  l^ask,  near  Tourmakeady,  Co. 
Mayo. 

ITavteula  inflata,  (Kutz.)    Fresh  water. 

Yalye  small,  inflkted  in  the  middle;  ends  narrowed,  produced, 
and  scarcely  capitate.  Striss  closely  granular,  radiate ;  length  *0010, 
breadth  *00035.    (Plate  34,  fig.  23.) 

Kiitz.  Bao.,  p.  99,  T.  iii.,  fig.  36.  YTm.  Sm.,  B.  D.,  Yol.  L,  p.  50, 
PL  zyii.,  fig.  158.  Grunow,  Yerhand.  der  £.  £.  ZooL  Bot.  Gesell., 
Band  x.,  1860,  p.  638,  T.  iy.,  fig.  41.  Ealfs,  in  Pritch.,  p.  899.    Hei- 


414  Pi'oceedings  of  the  Boyal  Irish  Academy. 

berg,  De  Danake  Siat.,  p.  82.    Donkin,  K.  H.  Brit.  Diat.,  p.  21, 
Pi.  iii.,  fig.  9, 

Lough  Kafik,  near  Tourmakeady,  Co.  Kayo.  Ditcli  near  town  of 
"Wexford.  Eiver  near  Glencar,  Co.  Kerry.  Eock  Mills,  Co.  Cork. 
Stream  BcUarena,  Co.  Derry.  Olenchree,  Kilcool,  Co.  Wicklow« 
KiyerDodder,  Killakee,  Co.  Dublin. 

Nwffieula  mesoUpta,  (Ehr.)    Fresh  water. 

Yalve  narrow,  triundalate;  ends  narrowed,  capitate;  stria  costate, 
radiate.    Length  '0025,  breadth  -0006. 

Kutz.  Bac.,  p.  101,  T.  xxviii.,  fig.  33,  and  T.  xxx.,  fig.  34,  who 
attributes  the  species  to  Ehrenberg.  Grunow,  Verhand.  der  K.  K. 
Zool.  Bot.  Gesell.,  Band  x.,  1860,  p.  520.  Balfs,  in  Pritch.,  p.  894. 
Cleve,  Om  Svenska  och  Korska  Diat.,  p.  225. — ^Pinnularia  mesolepta, 
Wm.  Sm.,  B.D.,  Vol.  i.,  p.  58,  PL  xix.,  fig.  182. 

Lough  ICoume  deposit.    Common  specially  in  mountain  districts. 

JVavictda  anylica,  (Balfs).    Presh  water. 

Yalve  broadly  elliptical ;  ends  produced ;  strias  costate ;  conyergent 
in  the  middle,  radiate  towards  the  ends ;  length  -0015,  breadth'00066, 
(Plate  84,  fig.  24.J 

Balfs,  in  Pritch.,  p.  900,  who  considers  the  form  identical  with 
Navicula  tumida,  Wm.  Smith.  Sonkin,  K.  H.  Brit.  Diat.,  p.  35, 
PI.  v.,  fig.  11.  The  latter  author  likewise  coincides  with  Balfs  as  to 
the  identity  of  the  species  with  that  of  Smith  referred  to.  There  is, 
however,  a  considerable  difierence  between  the  forms.  In  l^avicula 
anglica  the  valve  is  larger,  the  ends  less  capitate,  the  strias  more  dis- 
tant than  in  the  case  of  If  avicula  tumida ;  and  whereas  in  the  latter 
the  striae  are  punctate,  in  the  present  form  they  are  plainly  costate. 
Schumann,  Diat.  der  Hohen  Tatra,  p.  68. 

Killakee.  Trinity^  College  Botanical  (hardens,  Co.  Dublin.  Ditch 
near  Sligo.  Lough  Gill,  Co.  Kerry.  Lough  Mask,  near  Tourmakeady, 
Co.  Ifayo.    Dundalk,  Co.  Louth. 

Nor.  Bublinearts,  (Donkin).    Freshwater. 

Yalve  in  all  respects  like  the  tpyical  species,  except  that  the  out- 
lijLois  tearly  linear,  and  the  produced  ends  Wi4er;  length  '0012, 
breadth  -0005. 

Donkin,  N.  H.  Brit.  Diat.,  p.  35.  PI.  v.,  fig.  lib. 

Eillakee,  Co.  Dublin. 

Navxctila  eryptoe^hala,  (Kiitz.)    Fresh  water. 

Yalve  small,  narrow,  elliptical,  with  produced  slightly  capitate 
ends.  Striae  fine,  linear  radiate;  length  -0012,  breadth  '0003.  (Plate 
84,  fig.  25.J 

Kutz,  Bac.  p.  95,  T.  iii.,  fig.  20.  Wm.  Sm.,  B.  D.^  Yol.  i.,  p.  58, 


O'MsABA — Beport  on  the  Irish  Diatarhaeece.  41ft 

PI.  xvii.,  fig.  155,  Balfs,  in  Pritcli.y  p.  901 ;  Cleye,  Om  Sveilska  ocli 
NonkaDiat.,  p.  228.  Donkin,  N.  H.  Brit.  Diat.,  p.  87,  PI.  v.,  fig.  14. 
Scliizinami,  Diat.  der  Hohen  Tatra,  p.  68. 

Tacumsliaiie,  Co.  "Wexford.  Bowen's  Court,  Co.  Cork.  Lough 
Gill,  Co.  EeriT.  Lough  Mask,  near  Tourmakeady,  Co.  Mayo.  Dysart, 
Co.  Waterford. 

Navicuia  angmtatay  (Wm.  Smith).    Eresh  water. 
Valve  Tery  narrow,  elliptical ;  ends  produced  and  slightly  capitate. 
StriBB  fine,  linear,  radiate;  length  '0016,  breadth  -0003.    (Plate  84, 
fig.  26.) 

Wm.  8m.,  B.  D.,  Vol.  i.,  p.  52,  PI.  xvii.,  fig.  156.  Ralfs,  in 
Pritch.,  p.  901.  Castracane,  Cataloga  di  Diat.  raccolte  nella  Val.  In- 
trasca,  p.  12.  Schumann,  Diat.  der  Hohen  Tatra,  p.  68. — Navicuia 
cryptocephala,  var.  rhyncocephala,  Grunow,  Verhand.  der  K.  K.  ZooL 
Bot.  Gesell.,  Band  x.,  1860,  p.  527,  T.  iv.,  fig.  283. 

Bantry,  Co.  Cork.  Black  Castle,  Co.  Wicklow.  Malahide,  Co. 
DubHn.    Lough  Mask,  near  Tourmakeady,  Co.  Mayo. 

Ncmevia  lagerstedtiif  N,  S.  Fresh  water. 
'  Valve  small,  rhombic;  ends  slightly  produced.  Striae  obviously 
punctate,  radiate,  sub-distant;  when  the  centre  is  not  exactly  in 
focus,  there  is  the  appearance  of  a  narrow  staurof orm  band,  which  dis- 
appears when  properly  focused ;  length  '0010,  breadth  '0005.  (Plate 
84,  fig.  27.) 

Lough  Mask,  near  Tourmakeady,  Co,  Mayo.  Lough  GiU,  Co. 
Kerry.  In  the  latter,  marine  and  fresh  water  species  were  mingled, 
but  in  the  former  locality  marine  influence  was  impossible ;  the  form 
is  therefore  to  be  regarded  as  inhabiting  fresh  water. 

ITavicula gastrum,  (Ekr).    Freshwater. 

Volvo  rhombic ;  ends  scarcely  produced.  Striso  linear,  convergent 
in  the  middle,  radiate  towards  the  ends;  length  '0018,  breadth  '0009. 
(Plate  84,  fig.  28.) 

Kiitz.  Bac,  p.  94,  T.  zxviii.,  fig.  56,  who  regards  the  species  as 
identical  with  PInnularia  gastrum,  Ehrenberg.  Ealfs,  in  Pritch., 
p.  900.  Donkin,  N.  H.  Brit.  Diat.,  p.  22,  PL  iii.,  fig.  10.  This  figure 
represents  the  form  as  much  narrower,  and  the  ends  more  produced 
than  is  the  case  in  my  specimens. — ^Pinnularia  gastrum,  Bab.  Siissw. 
Diat.,  p.  44,  T.  vi.,  fig.  15.  This  last  figure  represents  the  strisa  as 
parallel,  which  is  not  accurate.  Gregory,  Q.  J.  M.  S.,  1855,  p.  41. 
Plate  iv.,  fig.  20. 

Dundalkj  Co.  Louth.  Lough  Gill,  Co.  Kerry.  Lough  Mask,  near 
Tourmakeady,  Co.  Mayo.    Lough  Moume  deposit/ 


416  Proceedings  of  the  Boyal  Irish  Academy. 

Navieula  hinodii,  (Ehr).    Fresh  water. 

Valve  small,  narrow,  incurred;  ends  produced,  apiculate.  Strise  fine, 
linear,  radiate;  length  *0012,  breadth  *0004;  breadth  in  the  middle 
•00035.     (Plate  34,  fig.  29.) 

Kutzing  (Bac.,  p.  100,  T.  iii.,  fig.  35,)  considers  the  form  iden- 
tical with  that  so  named  by  Ehrenberg.  Wm.  Sm.,  B.  D.,  Vol.  i., 
p.  53,  PL  xvii.,  fig.  159.  Eab.  Sussw.  Diat.,  p.  41,  T.  v.,  fig.  5,  and 
Fl.  Eur.  Alg.,  sect,  i.,  p.  203.  Balls,  in  Pritch.,  p.  893.  Castracane, 
Catalogo  di  Biat.  raccolte  nella  Yal.  Intrasca,  p.  12.  Heiberg,  Be 
Banske  Diat.,  p.  83.  Cleve,  Om  Syenska  och  Norska  Diat.,  p.  227. 
Donkin,  N.  H.  Brit.  Diat.,  p.  38,  PL  vi.,  fig.  3.  Schumann,  Diat.  der 
Hohen  Tatra,  p.  77. 

Powerscourt,  Co.  "Wicklow.  Lough  Gill,  Co.  Kerry.  Donkin 
considers  this  species  as  one  which  occurs  frequently  in  England ;  it 
is,  however,  one  of  very  rare  occurrence  in  Ireland. 

Navieula  die^phahy  (Ehr.)    Fresh  water. 

Yalve  small,  narrow^  linear,  narrowing  towards  the  produced 
slightly  capitate  ends.  Striae  obvious,  convergent  in  the  middle,  radiate 
towards  the  ends;  length  -0014,  breadth  -00055.    (Plate  34,  fig.  30.) 

KiitZi  Bac.,  p.  96,  T.  xxviii.,  figs.  60  and  62 ;  these  figures  incor- 
rectly describe  ihe  striae  as  parallel.-  Eutzing  attributes  the  species 
to  Ehrenberg.  Wm.  Sm.,  B.D.,  VoL  i.,  p.  63,  PL  xvii.,  fig.  157. 
Ghrunow,  Yerhand.  der  E.£.  Zool.  Bot.  Gesell.,  Band  x„  p.  538,  T.  iv., 
fig.  45.     Balfs,  in  Pritch.,  p.  902. 

Lough  Gill,  Go.  Kerry.  Lough  Neagh,  near  Lurgan,  Co.  Armagh. 
Camolin,  Co.  Wexford.  Friarstown,  Lucan,  Eillakee,  Biver  Dodder, 
Co.  Dublin.  Cushendun,  Co.  Antnm.  Powerscourt,  Co.  Wicklow. 
Lough  Moume  deposit. 

yapieuia  rhyncocephalaf  (Eutz.)    Fresh  water. 

Yalve  narrow,  elHptical ;  ends  considerably  produced,  not  capitate. 
Striae  distinct,  closely  moniliform,  radiate;  length  '0025,  breadth 
•0006.     (Plate  34,  fig.  31.) 

Kutz.  Bac,  p.  152,  T.  xxx.,  fig.  35.  Wm.  Sm.,  B.D.,  YoL  L, 
p.  47,  PL  xvi.,  fig.  132.  Grunow,  Yerhand.  der  K.  K.  Zool.  Bot. 
Gesell.,  Bandx.,  1860,  p.  530,  T.  iv.,  fig.  32.  Heiberg,  De  Danske 
Diat.,  p.  82.  Ralfs,  in  Pritch.,  p.  900,  PL  vii.,  fig.  68.  Cleve,  Om 
Svenska  och  Norska  Diat.,  p.  227.  Schumann,  Diat.  der  Hohen  Tatra, 
p.  68.  Eab.  Fl.  Eur.  Alg.,  sect.  I,  p.  196.  Donkin,  N.  H.  Brit. 
Diat.,  p.  38,  PL  vi.,  fig.  4. 

Eiver  Dodder,  ditch,  Dundrum,  Co.  Dublin.  Caumlough,  near 
Tralee,  Co.  Kerry.  Ulster  Canal,  near  Poyntzpass,  Co.  Armagh. 
Kilcool,  Co.  Wicklow. 


O'Meara — Beport  on  the  Irish  DiatomacecB,  417 

Ncwteula  globifera,  N.  S.    Eresh  water. 

Yalve  narrow,  margin  sliglitly  constricted ;  ends  constricted  and 
broadly  capitate.  Striae  extremely  fine,  close,  conyergent;  length 
.  -0018,  breadth  -0003.     (Plate  34,  fig.  32.) 

This  form  is  very  similar  to  that  described  by  Gregory  as  Pinnu- 
laria  globiceps,  Q.  J.  M.  S.,  1856,  p.  10,  PL  i.,  fig.  34;  but  differs  in 
the  following  respects :  in  Gbregoiy's  form  the  valve  is  obvionsly  ex- 
panded in  the  middle ;  in  this  it  is  linear,  with  the  appearance  of  a 
alight  constriction  in  the  middle ;  the  strias  in  this  are  much  finer,  and 
reach  the  median  line,  instead  of  leaving  a  central  stanroform  free 
band,  as  is  the  case  with  Pinnnlaria  globiceps. 

Camolin,  Co.  "Wexford. 

Navieula  rosteUifora,  (Gregory).    Marine  or  brackish  water. 

Valve  minute,  narrow,  linear ;  narrowed  towards  the  ends,  which  are 
apiculate.  Striae  costate,  convergent  in  the  middle;  frustnle  on  front 
view  constricted  in  the  middle ;  length  of  valve  .0013,  breadth  '0003. 
(Plate  34,  fig.  33.) 

Pinnxdaria  apiculata,  Gregory,  Q.  J.  M.  S.,  1856,  p.  41,  PI.  iv., 
fig.  21.  This  form  appears  to  be  the  same  which  Donkin  describes  as 
Navicula  apiculata,  De  Br^bisson,  and  Pinnularia  rostellata,  Gregoiy, 
Diat.,  of  Clyde,  p.  488,  PI.  ix.,  fig.  20.  See  Donkin,  N.H.  Bnt. 
Diat.,  p.  56,  PI.  viii.,  fig.  6.  Gregory  himself  evidently  regarded  the 
forms  as  distinct ;  and  comparison  of  the  two  compels  me  to  coincide 
with  that  eminent  observer.  Kavicula  apiculata,  De  Br^bisson,  and 
Pinnularia  rostellata,  Gregory,  are  obviously  identical,  and  quite 
different  from  the  present,  which  is  much  smaller  and  narrower  in 
proportion ;  the  striae  being  very  strong,  and  reaching  the  median  line, 
while  in  this  other  they  leave  a  considerable  blank  space  about  the 
central  nodule ;  the  rostrate  ends  too  in  the  latter  are  much  produced, 
while  in  this  species  they  are  very  short.  Gregory's  specific  term 
apiculata  ha^g  been  appropriated  by  De  Br^bisson,  ought  to  drop, 
and  the  form  so  distinctly  described  by  Gregory  bear  another  desig- 
nation, to  avoid  confusion. 

Iiough  Gill,  Co.  Kerry.    Portmamock,  Co.  Dublin. 

Natieula  eaneeUataf  (Donkin).    Marine. 

Yalve  large,  narrow,  linear,  with  cuneate  ends.  Striae  strongly 
costate ;  convergent  in  the  middle,  nearly  parallel  towards  the  ends ; 
length  *0036,  breadth  *0006.  Frustule  on  front  view  slightly  con- 
stricted, the  costae  appearing  in  a  broad  band.     (Plate  34,  fig.  34.) 

Donkin,  17.  H.  Brit.  Diat.,  p.  55,  PI.  viii.  fig.  4.  Navicula  trun- 
cata,  Donkin,  Q.  J.  M.  S.,  1861,  p.  9,  PI.  i.,  fig.  4,  and  changed  for 
the  present  designation,  the  former  name  having  been  anticipated  by 
Kutzing. — ^Pinnularia  truncata,  Bab.  PI.  Eur.  Alg.,  sect,  i.,  p.  217. 

Airan  Islands;  Stomachs  of  Ascidians,  Eoundstone  Bay;  Sto- 
machs of  Ascidians,  Broadhaven  Bray,  Co.  Galway.  Malahide,  Port- 
mamock, Co.  Dublin. 


418  Proceedings  of  the  Soyal  Irish  Academy. 

Navicula  minor ,  (Gregory).    Marine  or  bracldfih  water. 

Valve  small;  linear  witli  cuneate  ends,  strisB  linear,  nearly 
parallel  in  the  middle;  slightly  radiate  towards  the  ends;  length 
•0012,  breadth  -0004.     (Plate  34,  fig.  35.) 

Gregory,  Diat.  of  Clyde,  p.  477,  PI.  ix.,  fig.  1.  Gregory  mentions 
that  in  this  species  the  strias  do  not  reach  the  median  line.  In  this  parti-* 
cnlar,  the  present  form  does  not  answer  Gregory's  description, 
inasmuch  as  the  striae  plainly  reach  the  median  line,  but  in  all  other 
respects  there  is  such  agreement  as  to  make  me  think  the  forms  are 
identical.  Balfs  agrees  with  Gregory  in  all  particulars,  p.  909. 
Donkin  describes  a  form  under  this  name  which  he  regards  as  iden- 
tical with  that  described  by  Gregory.  See  N.  H.  Brit.  Diat.,  p.  57, 
PI.  Tiii.,  fig.  7.  The  forms,  however,  are  obviously  different,  that  of 
Donkin  being  elliptical,  lanceolate,  while  Gregory's  is  linear,  with 
cuneated  apices. 

Piles  of  wooden  bridge,  Dollymount  Strand,  Co.  Dublin.  Lough 
Gill,  Co.  Kerry. 


(m)    Diaphana,    Stria  not  obi&rvalh. 

Jfavicula perpusilla,  (Qmnow).    Freshwater. 

Valve  minute,  linear,  oblong,  with  rounded  ends,  and  slightly 
expanded  in  the  middle ;  length  *0005,  breadth  *0002.  (Plate  34, 
fig.  36.) 

Grunow,  Verhand.  der  K.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  552,  T.  iv.,  fig.  7  a. 

Lough  Kask,  near  Tourmakeady,  Co.  Mayo. 

Navicula  seminuhm,  (Grunow).    Fresh  water. 

Valve  very  minute,  oblong,  elliptical,  with  rounded  ends ;  length 
•0006,  breadth  -00025.     (Plate  34,  fig  37.) 

Grunow,  Verhand.  der  £.  K.  Zool.  Bot.  Gesell.,  Band  x.,  1860, 
p.  552,  T.  iv.,  fig.  2. 

Lough  Mask,  near  Tourmakeady,  Co.  Mayo. 


(    419     ) 


EXPLANATION  OF  CONTRACTIONS  AND  LIST  OF  REFERENCES. 


Agaidh,  Conspect.— ConspectuB  Ciiticiu  Diatomaoearttm.    1830. 

„       Syst. — Systema  Algamm.     1824, 
A.  N.  H.,  or  Ann.  Nat.  Hist.— Annals  and  Magazine  of  Natural  History. 
Bailey  Mic. — ICicroecopical  Obseryations  in  Smithaonian  Contributions  to  Enow- 

ledge.  1850. 
Berkeley.-^PaperB  in  Ann.  Nat.  Hist. 

Briglitwell.— Papers  in  Quarterly  Journal  of  Microscopical  Science. 
Castracane,  Catalogo,  &c. — Catalogo  de  Diatomea  raccolte  nella  Val  Intrasca. 

Oenora.     1866. 
Cleye,  Om  Svenska,  &c.— Om  Syenska  och  Norska  Diatomaceer  Ofyersigt  af  E. 

Yetenskaps-Akad.  Forhandlingar.     Stockholm.    1868. 
De  Br^bisson,  Notes  on,  &c. — Notes  on  some  French  Diatoms,  Journal  Queckett 

Club.    April,  1870. 
De  Br^bisson,  Diat.  du,  Ac.  —Diatom^  marines  du  Literal  de  Cherbourg. 
Donkin. — Papers  in  Quart.  Jour.  Micros.  Science. 
Donkin,    N.  H.  Brit    Diat. — Natural    History    of    the    British    Diatomaceae. 

London.    Tan  Voorst  (in  course  of  publication). 
Ehr.  Abh. — Ehrenberg,  Abhandlun^n,  Berlin  Akademie. 
Ehr.  Infus.—  Ehrenberg,  Die  Infusionsthierchen.     1838. 
Ehr.  Mic. — Ehrenberg,  Microgeologie. 
Gregory. — Papers  in  Quart.  Jour.  Micros.  Science. 
Ch«gory,  Diat.  of  Clyde. — ^New  forms  of  Marine  DiatomacesB  found  in  the  Frith  of 

Clyde.    Edinburgh,  1867. 
Oreyifie. — Papers  in  Quart.  Jour.  Micros.  Science. 

Grey.  Biit.  Flora Li  Hooker's  British  Flora  (Cryptogamia). 

Grunow. — Yerhand.  &c.,  Deber  neue  oder  ungeniigend  gekannte  Algen  in  Yerhand- 

lungen  der  E.  E.  Zoologisch-botanischen  GeseUschaft  in  Wien. 
Grunow. — BeiM  S.  M.  Noyara  um  die  Erde.     1868. 
Hanrey,  Manual. — Manual  of  the  British  Algee.    London,  1841. 
Heiberg. — De  Danske  Diatomeer.    Ejobenhayn.    1863. 
Eitton. — Papers  in  Science  Gossip. 

Eiitz.  Bac.— Eiitzing,  Die  Eiesselschaligen  BacciUarien.     1844. 
Eiitz.  Sp.  Alg. — Eiitzing,  Species  Algarum.     1849.        ^ 
Lagerstedt,  ^ty.  Diat.,  &c. — Sotyattens-Diatomaceer  fran  Spetsbergen  och  Beeren 

Eiland.    Stockholm.    1873. 
Lyngbye,  Tentamen  Hydrophytologie  Danics.     1819. 
Pntzer. — ITeber  Ban  und  Entwicklung  der  BadUariaceen.    Bonn.     1871. 
Rab.  Fl.  Eur.  Alg. — RabenhorBt,  Flora  Europssa  Algarum.     Leipsic.     1864. 
Rab.  Sitssw.  Diat. — Rabenhorst,  Die  Siisswasser  Diatomaceen.    Leipsig.    1853. 
Ralf s. — Papers  in  Ann.  Nat.  Hist. 

Balfs  in  Pntdiiurd's  History  of  Infusoria.    London.    1861. 
Boper. — Papers  in  Quart.  Jour.  Micros.  Science. 

Schmidt,  Atlas,  &c. — Atlas  der  Diatomaceen  Eunde.    Parts  1  to  4.     1875. 
Schmidt. — Die  Diatomaceen  aus  den  Grundproben  der  Nordsee  f ahrt.  Berlin.    1 875 . 
Schumann,  Diat. — Die  Diatomeen  der  Hohen  Tatra.    Wien.    1867. 
Schumann,  Die  Preussische  Diat. — Die  Preussische  Diatomeen,  vid4  Schriften  der 

Ph^-Oek.  GeseUschaft  zu  Eonigsberg.  1867. 
Thwaites. — Papers  in  Ann.  Nat.  Hist. 

W.  S.,  B.  D.— W.  Smith,  Synopsis  of  British  Diatomacese.    2  Vols.    1 853  and  1 856. 
Wallich. — PapeiB  in  Quart.  Jour.  Mic.  Science. 
Walker- Amott. — Papers  in  Quart.  Jour.  Mic.  Science. 
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R.I.A.  PROC,  RER.  II.,  VOL.  11.,  HCIF.NrR.  2  Y 


(    420    ) 


INDEX'TO  BEPOBT,  PART  I.,  ON  THE  IBISH  DIATOMACKS. 


The  Famiiies,  Sub'familus,  and  Genera  are  printed  in  Small  Capttale^  the  Specie* 
in  wdinarff  type.    Synanyme  are  marked  with  an  aaieriek. 


abnipta,  203. 
Aciii^MYVi.1^  337. 
aciculiuis,  304. 
AcTixucYciXrt,  208. 
Antixoitycj I  rs,  2CC. 
acros^hcnriu,  340. 
acummuta,  35o. 
acuta,  407. 
acuta,*  282. 
acutiusculo,  408. 
adiiaticum,  319. 
nquolifl,  282. 
a»tiva,  384. 
affinis  (Syn.),  311. 
aflinis  (Nav.),  367. 
affinu,*  367. 
alpina,  342. 
altemans,  278. 
ambigiio,  360. 
amblyoccroe,  278. 
amencona,  3«il. 
amphicephala,  209. 
amphiceros,  295. 
amphigomphuB,  367. 
AKiMtxrLEUiLA,  281,  320. 
AMiMiiPLEimiSJi;,  320. 
amphirhynchus,  307. 
amphisbasno,  303. 
AMPHiTEnuui,  275. 
anglica,  414. 
angUcuB,  270. 
ang:ulofla,  364. 
anguBta,  360.  ^ 
angustata,  41*5. 
anomalum,  287. 
antediluviana,  275. 
antiaua,  257. 
apicidata  (Kast.),  327. 
apiculata  (Nav.),  349. 
apioulata,*  376,  416. 
apis,  400. 


AllAClIXOlDLSCUS,  265. 

archciiano,  398. 
aniiatuiu,  318. 
areas,  311. 
aixruariii  fOrth.),  251. 
arcimiii  (Nav.),  411. 
aivohita,  208. 
ar^us,  209. 
arninicnsis,  395. 
AKTi:uif)Ki:hLA,  281. 
atiuosplicrifii,*  259. 

AVLA(X)D1SCUH,  270. 
AT7LACO.SU11A.*  254. 

AuuBCus,  270. 
auroa,*  283. 
amichalcio,  251. 
aurito,  274. 

bacilliun,  351. 
bacuhiSj  297. 
bayleyii,  275. 
balfouriana,  316. 
barbatiila,  310. 
barkoriano,  362. 

BEIIKFJ.I2YA,  331. 

bicopA,  302. 
biceps,*  352. 
biccapitata,  352. 

BlDDULPlOA,  272. 
biddulpbja,*  275. 
biddulphianiim,*  275. 

BiDDVLPJIIEJB,  271. 

binodis,  416. 
boeoMi  (Breb.),  388. 
boecldi  (Nav.),  848. 
bombiis,  401. 
borealis,  345. 
boiTerii,  246. 

BOEBISSONXA,  337. 

brebiBSonii,  350. 


Index  to  Beport  on  the  Irish  Diatomacece. 


421 


cflDTulea,  3-58. 
canncllata,  417; 
capituta  (Syn.)i  805. 
capitata  (Mast.]|  827. 
capiibina,  282. 
carassiii?,  412. 
cardinalis,  341. 
contTali*,  200.     , 
CniiATAULvs  *  271,  273. 
Ci;itAToxi:is,*  2ll. 
eei-es,  347. 
ecrvimif,  202. 
chi-vstaUiniim,  207. 
clavat<^  3S0. 
Clavat;k,  380. 
clepsydra,  347. 
cleyianA,  409. 
clo^ii,  320. 
cluthcnsifs  380. 
coj'C'oncilorinu',  470. 
coffoifonnw,  297* 

COLLCTOXEMA,  Jl29. 

coUii^inna,  3o4. 
comoidcs,  335. 
conciiuiiiis,  201* 
CoxFJiuvA,*  248. 
constritta  (Nar.J,  353. 
oonstiicta,  vat.  (Nav.),  393. 
eonstnicTi?,  283. 
convcTgcns,  325. 
CosciNoniMCUR,  259. 
co6cinorli<«<'iu«,  255. 
eostata  (Dent),  285. 
costata  (Mast.),  328. 
coetata  (Nav.),  393. 
oostatum,  290. 
crabro,  404. 

CuADPEDODinCUR,  200. 

CBAftsiNEiivi:H,  374. 
crasdnervLi,  375. 
toueiiA,  209. 
crotoncnM?,  283. 
cnicifpTa  (Nav.),  var.,  853. 
cnicifci-a  (Nav.),  354. 
cmoigonim,  333. 
chryptocopbaLi,  414. 
crux,  309. 
ciineata,  355. 
cuneata,  var.,  394. 
cti.«pMata,  3.57. 
CusriDAT/Tfi,  357. 
C!i!«pis,  358. 
Cy(;U)Ti:lla,  255. 
CtMatoseitu,  281. 
cynthia,  395. 
cyprinuB,  409. 

dallasiana,  259. 
danifMi,  var.  (Syn.),  309. 


danica  (Amph.),  322. 
dancoii,  320. 
da>idf(oma]m,  301. 
daAddsonii,  385. 
dcbilis,  313. 
decipiens,  359. 
dcl^nensLS,  373. 
dchcatissima,*  300. 
dcnariiis,  207. 
Dentiuklla,*  272. 
Dexticvla,  280,  285. 
dcnticiilata,  405. 
desmogonimn,  281. 
DiADcsMis,  337. 
DiAWMA,  280,  281,  291. 
dicephfda,  410. 
Dickii:a,  328. 
difkieii,  252. 
didynio,  402. 
didjrma,*  400,  403. 
digito-radiata,  409. 
dilwinii,  330. 

DiMciiioGiLVMMA,  280,  281, ! 
directa,  400. 
DiiiEOT.Te,  400. 
dirhyiiehus,  375. 

DlSCOVLFA,  * 

dL^tans  (MoL),  248. 
dbtans  mim.),  289. 
distans  (N;iv.),  343. 
divarir4ita,*  379. 
divcrgcns  (S<hiz.),  333. 
divcrgena  (Nav.),  345. 
divcrgcns,*  405. 
donkinca,  389. 
donkinii,  399. 
DoiiYriioiiA,*  281. 
duhia,  307. 
duodcnaiius,  207. 

ehrcnhorgii  (Cos.),  204. 
ohii3nbcrgii  (Arach.),  205. 
clegans  (Odont.),  288. 
elcgans  (Nav.),  303. 
elliptica  (Nav ),  384. 
clUptica,  var.,  391. 
elongatiim,  292. 
emarginatiis,  318. 
enervw,  280. 
entomon,  401. 
entomon,*  403. 
crg.'ulcnsis,  409. 
eiythroja,*  380. 
CBox,  309. 
EUCAMPIA,  271. 
endoxia,  397. 
cngcnia,  390.     ' 
Eupoiiiscus,  209. 
exccntricus,  270. 


422 


Proceedings  of  the  Royal  Irish  Academy, 


exigium,  278. 
exiUs,  406. 
eximium,  330. 
expleta,  390. 

faaciculata,*  306. 
favui,  277. 
fenestrata,  317. 
fimbriatus,  264. 
firma,*  366. 
flocculoga,  317. 
follifl,  360. 
forcipaU,  392. 
forficula,  397. 
fortis,  411. 
Fraoilaria,  280,  281. 

FHAOILARIBA,  280. 

fragilis,  331. 
franciscffi,  389. 
frauenfeldii,  312. 
Fbustulia,*  376. 
ful^iiB,  298. 
fulva,  368. 
fulTus,  269. 
fuAca,  383. 
fuAcata,  378. 
FuscAT^,  383. 

Gallionvlla,*  248. 
gallionii,  310. 
galvagenaiB,  410. 
gastrum,  416. 
gibba,  348. 
gibberula  *  368. 
gibemila,  368. 
GiBBOBA,  347. 
gigas,  261. 
globifera,  417. 
gracillima,  366. 
gracilliinum,  336. 
gracilis  (Syn.),  300. 
gracilis,  yar.,  303. 
gracilis  (Nay.),  407. 
Grakmatophora,  316. 
Grammonbma,*  281. 
grande,  291. 
granulata,  264. 
gregorii  TCos.),  263. 
gregorii  (Nav.),  403. 
greyilleii  (Mast),  328. 
greyilleii  (Schx.),  334. 
gnmdleiiana,  366. 
Grukowia,*  286. 
grunoyii,  362. 
grunoyii,  yar.,  392. 

harrissonii,  296. 
hebos,  364. 
helmentosum,  334. 


hemiptera,  349. 
hennedji,  387. 
heuflen,  411. 
hiberaiea,  389. 
hibemieus,  271. 
hormoides,  260. 
humerosa,  378. 
humilis,  413. 
hungarica,  412. 
hyalina,  293. 
Uydrosbra,  272. 
hyeniale,287. 

icostauron,  360. 
incisa,  404. 
incurya,  377. 
incunrata,  399. 
inflata,  413. 
inflata,*  369. 
inilatiun,  288. 
Integra,  366. 
intermedia,  406. 
intemipta  rXess.),  320. 
intemipta  (Nay.),  400. 
inyestiens,  299. 
iridis,  366. 
ISTHMIA,  279. 
IsTUMIRfi,  279. 

johnsonii,  373. 
jurgensii,  283. 

kittoniana,  388. 
kotzschyi,  370. 
kutzingiana,  266. 

laciniatom,  336. 
lacustris  (Tetr.),  318. 
lacustris  (Nay.),  380. 
beyissima,  367. 
lagerstedtii,  416. 
lanceolata,  yar.  (Syn.),  304. 
UmceoUta  (Mast.^,  324. 
lanceolata,  yar.  ^Nay.^,  344. 
lanceolata,  yar.  (Nay.;,  382. 
lanceolata  (Nay.),  406. 
Uta,  371. 
latissima,  379. 
latiuscula,  361. 
Latiusculjb,  361. 
lepida,*  413. 
leptoceroe,  296. 
liber,  366. 

libumica  (Rapb.),  296. 
libumica  (Nay.),  372. 
limosa,  368. 
LiMosA,  366. 
linearis,  yar.  fSyn.),  305. 
linearis,  var.  (Nav.),  371. 


Index  to  Report  on  the  Irish  Diatomacea. 


423 


linearis,  var.  (Xav.),  382. 
lineata,  366. 
lineatus,  264. 
Hneolata,*  375. 
litoralifl,*  861. 
Icmga,  844. 
longicepB,  806. 
longiflsima,  307. 
lorenziana,  296. 
Indda,  379. 
lunariBy  801. 
Ltbatjb,  890. 
lyra,  391. 
Ltbiooioum,  248. 

maciilA,  857. 
macilenta,  316. 
maculata,  250. 
maculoea,  881. 
major,  841. 
maiigliiiata,  898. 
marp^tuB,  264. 
manna,  815. 
marina,*  252,  877. 
marinnm,  289. 
Mastooloia,  823. 
maxima  CFrag.),  283. 
maxima  (Nay.),  871. 
MxLOsmA,  246. 
MBLOsnuLB,  246. 
menapienais,  346. 
meneghiniana,  256. 
memscua,  379. 

MSRIDION,  281. 

meaodon,  287. 
meaolepta  (Frag.),  284. 
meaolepta  (NaT.),  414. 
microetauron,  354. 

miniiTui^  293. 

minor,  265. 

minor,  var.  (Nay.),  892. 
minor  (Nav.),  418. 
minor,*  262. 
minus,  289. 
minntissima,*  804. 
minutula,*  894. 
minntum,  819. 

MONILIFKIUB,  377. 

monilifonnis,  268. 
monilifotmis,*  248 
montagnei,  260. 
moreii,  888. 
muoosmn,  838. 
musca,  399. 
mnsca,*  898. 
mutabilis,  285. 
mutna,  412. 

nanuto,  289. 


NAyicuLA,  339. 
NAyiouuLB,  822. 
nebnloea,  387. 
neglectum,  331. 
nervosa,  279. 
nitescens,  889. 
nitidus,  263. 
NrrzscHiA,  281. 
nitzschiodes,  812. 

NOBILBS,  340. 

nobUis,  340. 
nodosa,  852. 
normanni,  263. 
northumbrica,  411. 
notarisii,*  306. 
nnmmuloides,  248. 
nummuloides,*  250. 

obliqnata,*  280. 
obliquatum,*  280. 
oblonga,  344. 
oblongella,  376. 
obtusa  (Dent.),  285. 
obtosa  (Syn.),  808. 
obtusa,*  364. 
obtusom.  336. 
ocellata,^  287. 
oculus  iridis,  260. 
Odontblla,*  272. 
Odontidium,  280.  281,  286. 
Odontodiscus,  270. 

OlCPHALOPBLTA,  268. 

operculata,  257. 
oricbalcea,  353. 
omatnsl'  266. 
Orthosi&a,  250. 
ovalis,  385. 
ovnliim,  361. 
oxyrhynchus,  306. 

pacbypten,  342. 
palpebralis,  364. 
pandiua,*  404. 
papillifera,  372. 
napillosa,  258. 
Faralia,*  252. 
paraaiticimi,  835. 
parva,  var.  P^av.)>  348. 
parva,  var.  (Nav.K  386. 
parva,  var.  (Nav.),  397. 
pectinalis,*  355. 
personis,*  367. 
peUucida,  821. 
peUucida,*  399. 
peregrina,  408. 
perforatus,  26L 
peifrusilla,  418. 
rBRsnuATA,  406. 
pfitzeriana,  405. 


424 


Proceedings  of  the  JSoyal  Irish  Academy. 


pinnnto,  329. 
Kxxi  iJiuiA,*  839. 
iniinnliiria,  3'34. 
idxidiciilii,*  266. 
l'iJki;i(M^itAMMA,  2S0,  281,290. 
T»Iiiml>u-o]or,  372. 

I'OIXIKIILA,  240. 

pnctoxta,  .'iS?. 
protliu'ta  (Xav.),  370. 
prodiMta,  vjir.,«r.O. 
pulrhcllu  (l!id,),  275. 
pull  holla  (Syn.),  303. 
puhhra,  oIi2. 
pumtifa  (Orth.),  254. 
p!im:tita  (f'yi.),  2.ir. 
ptin<  tata  (Xtiv.),  3S0. 
pnm-tiilata,  377. 
pimrtiilatu8,2G5. 
piii^illa,  381. 
ptitcalis,  312. 
pygmu^i,  394« 

qitaflrato,  378. 
quamerenris,  3C1. 
qiiiiiqucloiularu,  275. 

rarlianSy  309. 
Ruliaita,  273. 
radial  I  IS,  2G2. 
radial  !!*,•  273. 
mdiolatiis,  202. 
nidiosa,  407. 
Radius.k,  407. 
Bali  KiA,  298. 
nilfMij  2(i3. 
rania8i««ininn,  334. 
roitaiig^idatu,  343. 
rcgiiia,  278. 
ivtiLsi,  Zoo. 
Rif  Ai:TK)xrxA,  318. 
RuAPiioxrw,  280,  281,  294. 
rbomliica  (Nav.)»  3.58. 
rhoml»i«-a,  var.,  384. 
rhomb«»idr>*.  374. 
i-honiliiu*  (IJidd.),  274. 
rboiiilMis  (Khap.),  295. 
rliym'M-opli.ila,  416. 
r)»ynro<'e]»l»Mla,*  var.,  416. 
rii  lianNoiiii,  3S9. 
roc'^.tn:!,  2il,  2.55. 
it)-(f'll.ita,»  319. 
roslrllilVni,  417. 
ruNtolliim.  370. 
ro^irata,  o-iO. 
rotuhi,  2-58. 
nipcstn\  347. 

ealina,  810. 
•andriana,  388. 


saiiBegniia,  895. 
scalaiis,  354. 
M-hmidtii,  395. 
Simiixum:m.\,  332. 
0copidoniin.*  373. 
M-otica,  2-59. 
MulphLs  270. 
8ii!trlloidr:<  (lUmp.),  295. 
B<ut«'lloidrrt  (Xav.),  381. 
8<'iiU'llum.  396. 
0(Hl(>nariii9,  267. 
BediictilLs  393. 
somen,  413. 
eemintdiim,  410. 
setniploivi,  304. 
Bcnariibs  267. 
septciidotnlaiiB,  275* 
BCiian.'',  374. 
ficriMMitiiia,  316. 
simulant  373. 
sintuitiuii.  286. 
siiijUiii  ((Vm.).  262. 
smiihti  (Syn.),  313. 
8niithii(MVt.),  327. 
Biiiilhii  (S<liix.),  333. 
Biiiilhii  (Xav.),  383. 
snulhii,*  403. 
Golaris,  410. 
FlKilhulata,  310. 
6)KX:t<il>ills,  390. 
ephu^rophonu  860. 
BpinucN-i,^  253,  255. 
Eplonilons,  308. 
Eplondida,  402. 
Fi»loD«lida,»  399. 
stauTDphora,  352. 
staiirophortim,  290. 
^auroptoro,  350. 
Stauuostils  281. 
stcllaris,  261. 
stokoidana,  389. 

STllLlTKf.L.\,  319. 
STiaATTLLK.K,  314. 

Btiiahda,  2;;3. 
8ii1»H-apitata,  356. 
eub-<  iiK-t:i,  398. 
Fiib-lloxills  247. 
6iil»-liiioans,  414. 
suh-orliicularis,  vnr.,  387. 
sub-<)rl»ii  idaiis,  var.,  391. 
sub-orliiiMihu*is  (Nav.),  396. 
8ti1>*n>t Hilda,  383. 
8Ml>-<<iiliu:i,  363. 
SI  I  h)  da,  371. 
sidral.i,  2-52. 
8Uix»rb:i,  209. 
SuUlUKLLK.Iv,  281. 

SvNLDitA,  280,  281, 296. 

SrSTEPUANIAf*  271. 


Index  to  R^ort  on  the  Irish  Diatoniacem. 


425 


Tabbllabia,  317. 
tabellaria  (Ralfsia),  293. 
tabellaria  (Nay.),  346. 
tabellaria,*  283,  284. 
tabulata,  311. 
tenera  *  300. 
tenue  (Odont.),  288. 
tenue  (Diat.),  292. 
tentiicoUis,  283. 
tentiirostriB,  360. 
temiiRHiTna,  300. 
tennes,  363. 
Tbssblla,  320. 
Tbtbactclus,  317. 

TOXABIUM,  301. 

translucida,  372. 
treyelyaxia,  844. 

TBICBBATIBifS,  276. 

Tbicbbathtm,  276, 277. 
Tbifabciatjb,  394. 
trilocularis,*  276. 
TaiNACBiA,  276,  278. 
Tkipodibcub,*  269. 
tnincata,  368. 
tnmcata,*  368,  417. 
tumens,  369. 
tmnida,  382. 

tumidB  Tar.  sub-salM,*  381. 
tmnida  yar.  lanceolata,*  382. 
tuzgida,  273. 


ulna,  306. 
nlvoidefl,  829; 
undata,  284. 
undosa,  369. 
imdnlata  (Syn.),  301. 
undulata  (I^av.),  343. 
iindulatufl,*  267. 
uni-punctata,  320. 

yarians,  247. 
yauchexuB,*  313. 
yeneta,  372. 
yicenarins,  267. 
yickersii,  406. 
yirescens,  282. 
yiridis,  341. 
yiridula,  410. 
yiilgare  (Diat.),  29U 
vulgare  (Coll.),  331. 

westii,  248,  249. 
-wHliamsonii  TDiad.),  337. 
williamaonii  (Nay.),  408. 
wrightii  (Lys.),  249. 
wrightii  (ISay.),  390. 

zellemBiB,  367 « 
zostereti,  408. 
Ztgoobbos,*  272,  274. 


R.  I.  A.  I'llOC,  8EU.  II.,  VOL.  11.,  «C1ENCK. 


2Z 


426  Proceedings  of  the  Royal  Irish  Academy. 

XXXYIII. — ^NoT£8  oir  son  Akomalibs  nr  the  coTTBas  of  Nzktxs  nr 

Man.    By  Alxxakdzk  Macalisteb,  M.B.,  Professor  of  Zoology  and 

Comparatiye  Anatomy,  Dublin  University,  M.B.I.  A. 
[Bead  NoremberS,  1875.] 
The  following  are  some  varieties  which  I  have  noticed  in  the  course 
of  nerves,  in  the  Dissecting  Boom  of  the  University  of  Dublin. 

1st.  In  a  thin  middle-aged  female  subject,  a  nerve,  about  as  large 
as  the  buccal,  arose  from  the  temporo-auricular,  after  the  union  of 
the  two  roots  of  that  trunk,  it  then  passed  over  the  internal  maxillary 
artery  (which  was  normal)  and  was  joined  by  a  small  twig  which 
arose  from  the  inferior  dental  nerve,  directly  below  the  foramen  ovale 
(thus  making  a  loop  around  the  artery).  The  trunk  so  formed  de- 
scended anterior  to  the  usual  inferior  dental  trunk,  and  pierced  the 
mandible  at  a  point  on  the  inner  side  of  the  bone  opposite  the  mental 
foramen,  entered  the  inferior  dental  canal  and  supplied  the  incisor 
teeth.  The  normal  inferior  dental  nerve  was  smaller  than  usual,  and 
lay  posterior  to  this  anomalous  trunk,  from  which  it  was  separated  by 
the  internal  maxillary  artery ;  the  mental  nerve  was  large,  and  was 
the  terminal  branch  of  the  inferior  dental,  all  the  filaments  of  that 
nerve  leaving  the  inferior  dental  canal  at  this  point. 

Cruveilhier  and  Sappey  describe  a  fine  anastomosis  between  the 
auriculo-temporal  and  the  inferior  dental,  but  I  am  not  aware  of  this 
variety  of  that  union  having  been  previously  observed. 

2nd.  In  a  female  subject  the  hypoglossal  nerve,  about  half-an-inch 
internal  to  its  thyro-hyoid  branch,  gave  off  a  transverse  branch  of 
communication  to  its  fellow  of  the  opposite  side ;  this  medial  branch 
arose  below  th^  twig  for  the  genio-hyoid,  and  passed  superficial  to  that 
muscle  and  under  the  mylo-hyoid ;  in  size  the  communicating  trunk 
was  nearly  equal  to  the  continued  trunk  of  that  nerve. 

Communications  between  the  hypoglossals  of  the  two  sides  are  on 
record  thus :  Szabadfoldy  (Virchow's  Archiv.  Band  38,  s.  177)  saw 
twigs  of  the  hypoglossus  of  one  side  passing  through  the  septum  of 
the  tongue  to  the  opposite  side ;  Bach  (Annotationes  Anatomicn  de 
nervis  hypoglosso  et  laryngeis :  Turici,  1834,  p.  10)  noticed  a  sling- 
like union  of  the  two  hypoglossi  in  the  tip  of  the  tongue,  and  my 
case  seems  to  be  a  variety,  on  a  lower  level  and  large  scale,  of  that 
method  of  union. 

3rd.  The  last  specimen  to  which  I  will  at  present  allude  is  one  of 
not  very  uncommon  occurrence.  In  a  female  subject  the  phrenic 
nerve  arose  as  usual  by  a  large  root  from  the  fourth  cervical  nerve  (its 
main  root  as  shown  by  Luschka  and  others),  but  its  usual  accessory 
branch  from  the  fifth  came  off  rather  larger  than  usual,  and  lower 
down  than  usual  from  its  parent  trunk  ;  it  then  ran  down  parallel  to 
the  main  root  but  0*5"  behind  it,  under  the  subclavian  vein,  and  the 
transversalis  humeri  and  colli  arteries,  passed  outside  the  internal  mam- 
mary, then  across  it,  and  joined  the  other  portion  of  the  phrenic  at  the 
level  of  the  upper  edge  of  the  first  rib.  Varieties  in  the  position  of 
these  two  roots  and  in  their  place  of  union  are  not  uncommon,  but 
I  have  never  seen  so  low  a  union  before. 


BoBiNSON — On  the  Cup  Anemometer.  427 


XKXIX. — On  the  Theobt  of  ths  Cup  Axemometfji,  and  the 
Detebmination  op  its  Constants.  By  the  Rev.  T.  R.  Robinson, 
D.J).,  M.R.LA.,  r.R.S.,  &c. 

[Bead  December  13,  1875.] 

I  HATE  described  this  instrument  in  a  paper  which  the  Academy  did 
me  the  honour  to  publish  in  their  "Transactions,"*  and  I  endeayoured 
to  approximate  to  its  theory  by  applying  to  it  Borda's  Theorem  for 
Undershot  Wheels,  and  adding  terms  for  the  resistance  due  to  the 
motion  of  the  cups  in  quiescent  air,  and  to  friction.  In  respect  of 
the  coefficients,  I  determined  in  actual  wind  the  ratio  of  the  pres- 
sures on  the  concave  and  convex  surfaces  of  the  cups  at  perpendicular 
incidence,  and  measured  the  difference  of  these  pressures,  by  a  spring- 
balance  connected  with  the  axle  of  my  Anemometer  (12-inch  cups 
with  arms  of  24)  for  velocities  of  wind  given  by  a  smaller  instrument, 
of  known  relation  to  the  large  one.  The  resistance  due  to  the  rotation 
was  measured  by  the  forces  required  to  make  the  cups  revolve  with 
given  velocities,  and  the  friction  similarly  measured.  These  data 
enabled  me  to  compute  the  ratio  of  the  wind's  velocity  to  that  of  the 
Anemometer,  supposing  friction  null,  which  I  found «  2*999,  and  to 
make  corrections  for  l£at  element  of  resistance.  There  were  in  this 
three  doubtful  assumptions;  that  the  mean  ratio  of  the  antagonist 
pressures  was  the  same  as  that  at  a  perpendicular  incidence ;  that 
Boida's  formula  is  strictly  applicable  to  curved  surfaces  moving  in  a 
free  current ;  and  that  the  resistance  in  quiescent  air  is  the  only  one 
to  be  considered  in  that  term  of  the  equation  which  includes  r*.  I 
therefore  had  very  little  confidence  in  this  theory.  However,  I  tested 
it  by  experiment.  A  small  Anemometer  was  fixed  to  a  whirling 
machine  which  carried  it  through  the  air  with  velocities  varying  from 
11-69  miles  an  hour  to  3'93.  And  33  such  observations  gave  for  the 
ratio  3-004.  In  water  it  gave  3*020,  the  results  with  2,  3,  and  4  cups 
being  almost  identical.  I  tried  to  ascertain  the  agreement  of  this 
instrument  with  the  large  one,  by  comparing  their  simultaneous  read- 
ings, but  the  irregularity  of  the  wind,  even  at  a  few  feet  distance, 
made  the  trial  ineffectual.  However,  the  agreement  of  the  two 
ratios  given  above  seemed  satisfactory,  and  I  pursued  the  investigation 
no  farther,  till  my  attention  was  recently  recalled  to  it  by  a  memoirf 
by  M.  Dohrandt,  of  the  Petersburgh  Meteorological  Observatory,  which 
appeared  in  the  ''Repertorium  fiir  Meteorologie,"  con  taming  an 
eli^rate  series  of  experiments  made  chiefly  to  determine  the  relation 
between  the  rotation- velocity  of  the  Cup  Anemometer  and  that  of  the 
wind. 


*  TranBBctioiu,  Vol.  xzii..  Part  I.,  Science,  p.  156. 
t  Repertorium  fiir  Meteorologie,  Bandir.,  1874. 

2Z2 


428  Proceedings  of  the  Royal  IrUh  Academy. 

Thcj  were  made  by  means  of  the  whirling  machine  invented  by 
Bobins  130  years  ago,  and  subsequently  used  by  other  English  phy- 
sicists for  experiments  on  the  air's  resistance.  This  apparatus  was 
established  in  the  Hall  of  the  Central  Physical  Observatory  at  8t. 
Petersburgh  on  a  grand  scale.  Its  horizontal  arms  were  11*26  feet 
long,  braced  to  prevent  flexure,  and  20*3  feet  above  the  floor.  The 
Anemometers  were  attached  to  one  of  the  arms  at  10*92  feet  from  the 
centre  of  rotation,  and,  except  in  one  instance,  with  their  planes  of 
rotation  parallel  to  that  of  the  arms.  The  number  of  turns  of  the 
latter  was  recorded  by  an  electric  register,  and  the  seconds  of  each 
experiment  noted  with  a  chronometer.  These  gave  the  velocity  with 
which  the  axis  of  the  Anemometer  passed  through  the  air.  It  was 
moved,  in  a  way  not  corresponding  to  the  general  excellence  of  its 
details,  by  two  men  impelling  opposite  bars  projecting  from  the  axle ; 
and  therefore  the  velocities  communicated  to  it  were  not  very  uniform. 
The  greatest  speed  obtained  was  40  kil.  =  25  miles  per  hour. 

The  velocity  with  which  the  centre  of  its  cups  revolved  was  given 
by  the  number  of  its  revolutions  and  its  radius.  M.  Dohrandt  was 
well  aware  of  the  circumstances  which  make  a  difference  between 
the  motion  of  an  Anemometer  carried  through  quiescent  air,  and  of  one 
acted  on  in  a  fixed  station  by  a  current  of  wind ;  and  he  showed  great 
sagacity  and  experimental  skill  in  trying  to  eliminate  the  influence  of 
the  two  most  important  of  them. 

First,  it  is  obvious  that  a  cup  which  is  within  the  track  of  its  axis 
meets  the  air  with  less  velocity  than  one  outside,  and  therefore  receives 
a  less  impulse  than  when  outside ;  from  which  it  follows  that  when  the 
machine  revolves  in  the  same  direction  with  the  Anemometer,  the 
latter  revolves  more  slowly  than  in  the  reverse  case.  He,  therefore,  in 
every  case  took  the  mean  result  of  the  two  directions. 

Secondly,  the  rotation  of  the  apparatus  drags  with  it  a  quantity  of 
air,  producing  a  circular  current  which  is  sensible  even  at  the  floor 
20  feet  below ;  therefore  the  Anemometer  meets  the  air  with  a  less 
velocity  than  if  that  were  quiescent.  He  measured  this  draught  by 
a  "  Woltman*s  Fly,"  a  light  windmill,  established  with  its  axis  nearly 
in  the  plane  of  the  Anemometer's  rotation,  and  parallel  to  the  tangent 
of  its  track,  find  from  12  inches  to  20  inches  from  that  track.  He 
estimated  its  velocity  to  be  about  0*05  of  that  of  the  machine,  and, 
allowing  for  it,  concluded  that  F,  the  velocity  with  which  an  Anemo- 
meter is  moved  through  still  air,  is  connected  with  v  the  velocity  of 
the  centre  of  the  cups  by  the  equation  F=  «  +  Iv  (inkilom.) 

He  determined  these  constants  for  five  Anemometers  by  the  whirl- 
ing machine;  and  four  others  by  comparison  with  them.  I  give 
their  values  for  the  first  set,  adding  for  each  the  length  of  its  aims 
and  diameter  of  its  cups  in  inches. 


KoBiNSON — On  the  Cup  Anemometer. 


429 


Nams  of  Maker. 

a.  Kil. 

b 

Length  of 
radius. 

Diameter. 

Browning,  .... 

3-66 

2-2271 

11-99 

6-84 

CaseUa,  317    .    .    . 

2-66 

2-7648 

6-76 

3-016 

CaseUa,  318     .     .     . 

1-90 

2-8472 

6-76 

3-016 

Nowiko£F,   .... 

1-81 

2-8979 

8-61 

3-77 

No.  4, 

2-49 

2*5293 

4-86 

4-11 

He  gives  also  the  result  of  a  trial  to  determine  the  constants  for 
Browning  hy  carrying  it  on  the  tender  of  a  locomotive  to  and  from 
Zarsko-Selo,  a  distance  of  19  ver8ts  =  20*27  k.  He  gives  the  mean  V 
going  32-14  and  returning  2690;  and  v  =  13-76  and  9-17.  This 
reference  to  hourly  velocities  rather  masks  the  result,  and  it  is  sim- 
pler to  say  that  while  the  engine  traversed  20*27,  the  Anemometer 
showed  8*675  going  and  6*837  returning.  The  difference  is  referred 
to  a  light  wind  which  hlew.  He  endeavoured  to  estimate  the  effects 
of  this  hy  means  of  an  Anemometer  Breguet  fixed  on  the  tower  of 
the  Observatory ;  but  as  this  was  77  feet  above  the  ground,  and  from 
4  to  25  k.  from  the  rail,  he  attaches  little  importance  to  its  data, 
except  inferring  that  the  direction  of  the  wind  made  a  mean  angle  of 
22^  with  that  of  the  rail ;  and  comparing  the  F^s  going  and  coming, 
he  deduces  for  the  mean  velocity  of  the  wind  along  the  rail  {hy  hia 
formula^  first  assuming  ap=  2  and  then  3)  2*8 ;  (Breguet  would  give  5*2). 
Prom  these  he  finds  for  Browning  a  =  3*1 1 ;  6  =  2*3091. 

Lastly,  he  placed  the  two  Casellas  and  Browning  on  the  Observatory 
tower,  where  two  others  were  permanently  established.  But,  as  the 
platform  was  only  10  feet  5  inches  square,  they  must  have  been  too 
close  to  act  freely.  However,  he  got  by  his  equations  very  nearly 
accordant  results  for  the  three.*    The  remainder  of  the  paper  is  occu- 


•  Similar  but  more  extensive  experiments  were  made  by  the  Rev.  Fenwick 
Stow  f"  MeteorologicalJoumal,'*  vol.  i.),  of  which  I  learned  the  existence  from 
M.  Donrandt's  paper.  Six  Anemometers  of  different  types  from  the  Kew  one, 
r  =  24  inches,  rf  =  9  inches,  to  Casella  r  =  6.7,  rf  =  3.01,  were  established  on  open 
ground,  and  their  indications  were  taken  during  a  considerable  period,  and  with 
values  of  F",  as  given  by  the  Kew,  ranging  from  3«"  to  34".  He  finds  that  instru- 
ments with  short  arms  do  not  agree  even  approximately  with  the  Kew  one,  except 
at  low  velocities;  that  those  which  have  the  smaller  cups  relative  to  the  arms, 
maintain  at  all  velocities  a  tolerably  even  percentage  of  Kew,  and  that,  in  all 
cases  (supposing  the  V  given  by  Kew  to  be  that  of  the  wind),  they  move  more 
rapidly  in  prox>ortion  to  ttie  wind  «»  V  is  gmaller.  This  is  in  complete  opposition 
to  Dohrandt's  results,  and  (as  will  be  seen)  to  theory.    Comparing  Casella  and  Mr. 


430 


Proeetdingi  of  the  Boyal  Iruh  Aeademf. 


?ied  with  determining  equations  for  Woltman's  Fly,  and  Wilde's  Wind 
tablet.  Too  much  praise  cannot  be  given  to  the  ability  and  care  with 
which  these  experiments  were  carried  out,  and  it  is  not  from  any 
failure  in  these  respects  that  they  cannot  be  depended  on  to  give  reli- 
able values  of  Anemometer  constants,  or  correct  the  theory  of  these 
instruments ;  but  they  are  all  liable  to  several  causes  of  uncertainty. 
Even  had  the  apparatus  been  established  in  free  air,  it  is  probable 
that  the  Anemometer's  indications  would  be  different  from  those  given 
by  the  same  instrument  if  stationary,  and  acted  on  by  a  current  of 
wind.  Experiments  show  that  a  plane  surface  moved  through  water 
in  a  direction  perpendicular  to  itself  is  less  pressed  than  when  a 
stream  of  water  impinges  on  it  with  the  same  velocity.  I  know  Colonel 
Duchemin's  researches  only  by  M.  Dohrandt's  niference  to  them, 
and  his  results  seem  excessive;  but  De  Buat's  experiments  give 
that  the  ratio  is  as  1186  :  1 ;  Yince  makes  it  1*2 :  1.  The  pressure  is 
also  differently  distributed  over  the  surface  in  the  two  cases.  It  is 
possible  that  if  the  plane  were  moved  down  the  stream  with  a  less 
velocity  than  it  has,  the  difference  might  be  still  greater.  I  am  not 
acquainted  with  any  experiments  of  this  kind  made  on  curved  surfaces. 
Similar  differences  may  be  expected  to  exist  between  the  motion  of  the 
body  and  that  of  the  fluid  in  elastic  media,  though  we  cannot  say 
what  would  be  their  amount,  supposing  them  to  exist,  though  probably 


Stow*s  No.  6,  rs9,  <f=4  inches,  with  Nowikoff  for  V  nearly  equal,  and  taking 
V  =  i  of  his  number,  as  all  the  instruments  register  3r,  I  find — 


CftMllS. 

Slow. 

{caaella. 

Dohr. 

'  No.  6. 

Stow. 

Nowlkoff, 

CaielUu 

RoWnKm. 

v 

9 

r 

V 

• 

i      y. 

V 

V 

r 

9 

V 

F' 

• 

34-8 

3-936 

3419 

3-163 

360 

3-696 

33*31 

3-225 

21-96 

3-263 

26-2 

8-866 

26-94 

3-276 

24-7 

3-681 

27-29 

3-347 

1600 

3-564 

22-7 

3-896 

2116 

3-380 

.    21-8 

3-644 

22-37 

3-361 

11-40 

3-654 

20-2 

3-816 

20-27 

3-673 

16-3 

3-646 

16-98 

3463 

10-58 

3861 

16-2 

3-764 

j    16-31 

3-699 

7-9 

3-619 

7-74 

3-957 

9-79 

4-140 

110 

3-766 

1112 

3-636 

, , 

, , 

, , 

710 

4170 

7-4 

3-768 

' 

They  are  also  inconsistent  with  my  own  observations,  made  many  years  ago,  to 
compare  a  Casella  with  my  own  Anemometer ;  the  results  of  which  1  give.  I  re- 
gret that  I  was  not  acquainted  with  Hr.  Stow's  experiments  during  their  progreaa, 
as  I  would  have  requested  him  to  measure  for  each  of  his  instruments  my  con- 
tants  /o'  +  b,  and  /.  A  knowledge  of  these  might  have  modified  his  numbers 
considerably.  He  seems  to  have  not  duly  appreciated  the  extent  to  which  very 
slight  modifications  of  the  figure  of  the  ground  will  influence  the  velocity  of  the 
wind,  and  the  considerable  variations  of  it  which  occur  even  at  small  lateral  dis- 
tances. From  my  own  observations  of  these  facts  I  cannot  place  any  reliance  on 
ihii  mode  of  determining  Anemometer  constants. 


lloBiNsoN — On  the  Cup  Anemofneter,  431 

they  would  be  less.*  But,  in  the  investigations  which  we  are  consi- 
dering, the  air  was  far  from  free.  The  part  of  the  Hall  occupied  by  the 
apparatus  was  27*4  feet  by  26*9  feet ;  26*3  feet  high  in  the  centre,  22*6 
feet  at  the  walls.  The  rotating  arms  were  20*3  feet  from  the  ground  ; 
but  the  cross  of  the  Anemometer  was  only  17*64  inches  from  the  roof 
(this  was  necessary  from  the  nature  of  the  frame  supporting  the  vertical 
axis,  which  had  been  constructed  for  another  purpose),  and  the  centres 
of  the  cups  were  from  34  inches  to  30  inches  distant  from  the  main 
line  of  the  walls.  Part  of  the  Hall  communicating  with  this  nearly 
cubical  space  was  only  11*7  feet  high,  and  on  the  east  wall  was  a  smaU 
gallery  15*4  feet  above  the  ground,  in  which  an  observer  was  stationed. 
It  is  evident  from  these  details  that  the  air  put  in  motion  by  the 
rapid  rotation  of  the  arms  (11*25  feet  long,  and  2*4  inches  dia- 
meter, with  braces  8*68  feet  long,  and  0*6  inches  diameter),  and  by 
the  fixed  parts  of  the  Anemometer  must  have  been  thrown  into  irre- 
gular eddies,  interfering  with  its  action  on  the  curved  surfaces  of  the 
cups,  and  that  they  must  have  been  differently  impelled  when  nearest 
to  the  walls,  and  when  opposite  to  tlie  angles  of  the  room.  The 
current  measured  by  the  Woltman  cannot  be  regarded  as  representing 
that  in  the  Anemometer  track,  for,  besides  being  outside  that,  it 
must  be  modified  by  the  gallery  and  observer's  body.  He  tried  to 
examine  it  by  small  balloons  filled  with  coal  gas,  and  loaded  so  as  to 
be  in  equilibrio,  **  but  they  travelled  iiregularly,  sometimes  within, 
sometimes  without  the  Anemometer's  track,  sometimes  above,  some- 
times below  it." 

He  found,  also,  that  the  revolutions  of  the  Anemometer  tried  were 
sensibly  diminished,  when  another  one,  or  even  the  small  Woltman, 
was  put  on  the  other  arm  22  feet  distant.  (I  think  some  useful  in- 
formation as  to  the  motion  of  the  air  might  have  been  obtained  by 
placing  over  the  Anemometer  a  tube  as  long  as  its  diameter,  perforated 
with  several  holes,  and  discharging  through  these  jets  of  smoke,  as 
was  done  by  Dr.  Ball  in  his  experiments  on  vortex  rings).  M.  Doh- 
randt  has  here  overlooked  three  disturbing  elements.  A  part  of  the 
resistance  to  an  Anemometer  is  work  done  in  throwing  out  from  its 
centre  a  quantity  of  air  by  centrifugal  force ;  this  must  be  interfered 
with  by  the  walls,  &c.  Another  is,  that  the  rotation  of  the  whirling 
machine  itself  must,  by  the  same  centrifugal  force,  produce  an  outward 
current.  He  refers  to  this  as  increasing  the  density  of  the  air  near  the 
walls,  but  it  must  escape  above  and  below,  and  the  stream  so  pro- 
duced must  help  to  turn  the  cups.  What  its  amount  is  cannot,  under 
the  circumstances,  be  determined  a  priori,  but  it  probably  more  than 
counteracts  the  circular  current. 


*  It  is,  however,  to  be  remarked,  that  the  amall  Anemometer  mentioned  in  the 
begtnning  of  this  paper  ^ve  almost  identical  Tesnlts  when  carried  through  air.  and 
when  immersed  in  running  water. 


432  Proceedings  of  the  Royal  IrUk  Academy. 

Thirdly,  the  centrifugal  force  due  to  the  circular  track  of  the 
Anemometer's  axle  must  make  it  press  against  its  upper  hearing,  and 
thus  increase  the  friction,  unless,  as  in  my  original  instrument,  there 
are  mechanical  antifriction  appliances  at  this  part ;  hut  this  does  not 
seem  to  have  heen  the  case  in  those  used  hy  M.  Dohrandt.  With 
his  machine,  when  F=  40  JT,  this  lateral  pressure  will  he  3*78  times 
the  weight  of  the  moving  parts,  and  the  additional  friction  at  the 
hearing  ahout  01  of  this.* 

It  is  not  quite  correct  to  assume  that  the  mean  of  the  results  ob- 
tained hy  rotating  the  machine  in  opposite  directions  is  identical  with 
what  would  hare  heen  given  hy  a  rectilinear  motion ;  for  it  cannot  be 
douhted  that  the  equation  which  gives  the  relation  hetween  Fand  r, 
must  contain  F*,  t?',  and  Vv ;  and  it  is  obvious  that  half  the  sums  of 
these  will  differ  from  those  of  the  mean,  Fand  r,  though  not  consider- 
ahly.  M.  Dohrandt  tried  to  avoid  the  necessity  of  this  double  rota- 
tion by  (as  I  had  done)  making  the  plane  of  the  Anemometer's  rotation 
perpendicular  to  that  of  the  arms.  In  this  case  the  direction  of  the 
rotation  should  make  no  difference,  and  the  centrifugal  current  heing 
perpendicular  to  the  Anemometer  plane  should,  hut  for  the  eddies, 
have  no  effect. f   But  this  is  far  from  being  the  case.  Allowing  0-05  F", 

for  the  circular  current,  the  ratio  -  is  in  the  two  cases 

€7 
V 

No.  4. 


He  remarks  that  nothing  can  he  made  of  this,  and  the  reason  is  ob- 
vious, for  the  axis  of  the  Anemometer  is  only  2*8  feet  from  the  roof 
and  its  cups  2-3  feet.  In  a  freer  space,  he  remarks,  this  mode  would 
be  preferable  to  the  one  he  employed.  With  respect  to  it,  I  think  the 
preceding  remarks  will  suffice  to  show  that  it  is  very  doubtful  whether 
his  F  represents  the  wind  which  it  is  supposed  to  represent,  and  that 
instead  of  deducting  any  allowance  for  the  circidar  current,  it  might 
be  nearer  the  truth  to  add  one  for  the  centrifugal  forces  and  the  eddies; 
and  certainly  the  resistance  is  different  from  that  which  would  occur 
in  the  ordinary  use  of  an  Anemometer. 

The  railway  experiment  is  not  more  conclusive.     No  reliance  can 


•  In  one  of  Casella's  conBtniction,  of  the  same  dimensions  as  (7318,  the  moveable 
parts  weigh  3500  grs.  Hence,  for  r=26  miles,  the  additional  friction  wonld  be 
19*6  grs.    Six  times  tiie  normal  one. 

t  An  Anemometer,  with  3-ineh  cups,  fixed  to  the  axle  of  the  vane  of  my  Ane* 
mometer,  so  that  its  axis  was  always  in  the  direction  of  the  wind,  made  48  revolu- 
tions in  6".  In  M.  Dohrandt's  experiment  the  eddies  were  probably  much  stronger 
Jthan  in  the  above  case. 


32-01  K.  —  =  3050; 

F-  ir=  32-37  K. 

F 
—2-770 

1^ 

24-57                 2-558 
19-53                 3179 
18-74                3-362 

22-11 
21-84 
1513 

2-809 
2-805 
2-974 

BoBiKSON — Ofi  the  Cup  Anemometer.  433 

be  placed  on  his  estimation  of  the  wind's  effect ;  and  any  attempt  to 
combine  the  results  for  each  verst  going  and  returning  seems  hopeless. 
The  space,  for  instance,  traversed  by  the  cups,  in  passing  No.  2,  are 
$46-11  me.  and  319*25  me. ;  the  Fs  are  21*22  k,  and  24*38  ;t;   the 

Z  1*953  and  3*342;  for  No.  10,  they  are  403*3,  386-5 ;  36*58,  35*98, 

V 

and  2*645,  2*741. 

M.  Dohrandt  only  considers  that  part  of  the  wind  which  acts  in 
the  mean  direction  of  the  rail,  but  its  rectangular  component  cannot 
be  omitted,  for  it  can  turn  the  Anemometer  both  going  and  coming. 
And  there  is  uncertainty  about  the  real  velocity  with  which  the  air, 
in  such  trials,  passes  the  instrument ;  a  body  moving  through  a  fluid 
carries  before  and  behind  it  a  mass  of  quiescent  fluid,  but  at  the  side 
of  a  ship  it  is  well  known  that  the  water  moves  astern,  in  consequence 
of  its  displacement  in  front. 

The  same  is  probably  the  case  on  the  tender  of  a  train,  especially 
between  embankments,  in  which  case  the  V  will  be  greater  than  what 
is  given  in  the  Table. 

His  determinations  of  the  ratio  differ,  as  might  be  expected  from 
the  preceding  remarks,  considerably  from  mine,  always  in  defect,  but 

unequally  in  the  different  instruments.     It  must,  however,  be  observed, 

jr 

that  we  mean  different  things  by  the  term  ratio.     My  m  = u  being 

v  +  u 

a  variable,  depending  on  the  friction  and  v  ;♦  his  is  — H-  ,  abeingacon- 
stant.t  I  must  also  remark  that  his  equation  V=  a  +  ^  is  strong  evi- 
dence that  the  circumstances  under  which  his  experiments  were  made 
are  abnormal.  In  this  instrument,  when  a  permanent  state  of  rotation 
is  established,  the  mean  impelling  force  must  be  equal  to  the  mean 
resistance.  Now,  with  all  the  defects  of  this  branch  of  Hydrody- 
namics, it  is  certain  that  the  equation  expressing  this  equality  must 
contain  V^t^  and  Vv ;  and  one  in  which  they  do  not  appear  cannot 
give  the  V  which  corresponds  to  a  r  produced  by  the  action  of  the  real 
wind. 


^  *  I  wish  to  coirect  a  mistake  in  my  paper  on  the  Anemometer  (1.  c.)  I  stated  that 
m  is  independent  of  the  size  of  the  instrument,  forgetting  that  b\  the  co-efficient  of 
that  part  of  the  resistance  which  is  caused  by  centnfugal  force,  is  in  part  inversely 
as  the  arm  of  the  Anemometer.  Therefore  m  must  be  larger  in  small  instruments 
than  in  large  ones.    On  the  other  hand,  the  divisor  of/  is  less. 

t  This  constant  differs  considerably,  and  more  than  can  be  explained  by  mere 
friction  in  his  instruments.  The  two  Casellas,  which  are  quite  'similar,  are  special 
examples  of  this.  In  those  cases  where  he  extends  the  interpolation  to  f  * ;  the  a 
differs  from  that  of  the  simple  equation  so  much  that  we  can  scarcely  suppose  either 
to  be  a  true  friction  co-efficient.  It  is  to  be  regretted  that  it  did  not  occur  to  him 
to  determine  the  friction  of  each  Anemometer,  and  the  V  at  which  they  began  to 
move ;  a  knowledge  of  these  would  have  made  his  results  more  useful. 


434 


Froceeditig$  of  the  Royal  Iri$h  Academy. 


Notwithstanding  these  defects  in  M.  Dohiandt's  experiments,  I 
think  they  show  the  necessity  of  farther  investigation ;  and  as  I  am 
conTinced  of  the  advantages  which  this  instrument  possesses  as  a 
recorder  of  the  wind's  velocity,  1  think  it  may  he  useful  to  point  out 
the  processes  by  which,  as  it  seems  to  me,  a  closer  approximation  to  its 
theory  may  be  obtained,  and  the  co-efflcients  of  the  resulting  equation 
deduced  with  sufficient  certainty.  If  in  doing  this  I  seem  to  go  too 
minutely  into  details,  I  must  plead  in  excuse  the  great  complexity  of 
the  inquiry,  and  my  desire  to  omit  nothing  of  importance. 

Considering  a  single  cup  of  an  Anemometer  exposed  to  a  current 
of  air  of  velocity  F,  making  an  angle  B  with  its  arm,  and  incident  on 
its  concave  suiface;  its  pressure  on  that  sur- 
face =^  SF*  X  a;  a  being  a  co-efficient  depending 
on  Of  and  on  the  figure  of  the  cup,  and  S  the 
area  of  its  mouth  :  the  power  of  this  pressure  to 
make  the  cup  revolve  is  Sa  F'  x  sin  ^.  But 
suppose  the  cup  in  motion  with  the  velocity  v, 
and  convex  foremost,  this  motion  lessens  the 
effect  of  F,  and  instead  of  F,  we  must  use  the 
resultant  of  it  and  v.  This  resultant  also  makes 
with  the  arm  an  angle  ^,  different  from  0 ;  let 
AR  be  the  arm,  AV  a,  hue  proportional  to  F 
AB  X  to  AE,  as  v ;  the  diagonal  BV  oi  the 
parallelogram  under  them  =  R  the  resultant 
when  Fand  v  are  in  the  same  direction ;  CA  =  R! 
that  when  they  are  in  opposite  ones.  Drawing 
BL\\toARf  FBD^ifi.    It  is  obvious  that  i?  «  F>  +  v>  t  2  Fv  sin  tf ,  and 


sin^< 


Fsin  $^v 

ROT^ 


,  cos  ^  : 


FC08$ 

RotR!' 


the  lower  signs  belonging  to  the  case  R^,  Hence  for  jS'a  F^  sin  ^  we 
must  use  SaR^  aii^^Sa{F*+i^^2Fv  an$)xBmil^.  ^is  best  found 
by  the  equation — 

secant  0  F 

tan  ^»tan^  ?  ,  m  beings  — . 

171  V 


It  will  be  shown  (Y.)  that  m,  though  changing  with  r,  variea 
little ;  and  taking  its  mean  value,  no  important  error  will  arise  from 
assuming  it  constant. 

This  is  the  positive  or  impelling  pressure.  (1.) 

When  sboiO^iiy  it  should  vanish ;  but  in  fact  I  found  that  one  cup 
exposed  to  the  wind  has  a  positive  pressure  far  beyond  this  point,  not 
resting  till  210^.  I  could  not  determine  the  opposite  point  of  rest, 
because  the  least  eddy  of  the  wind  set  the  cup  in  rotation.  I  do  not 
know  whether  this  curious  fact  arises  from  the  wind  eddying  into  the 


BoBiNSON — On  the  Cup  Anemometer.  435 

eoncaTe,  or  from  minus  pressnre  behind  the  cup ;  *  but  it  is  the  more 
remarkable,  because  in  this  case  more  than  half  a  hemisphere  is 
exposed  to  negative  action.  This  seems  to  imply  that  the  ori^al 
expression  for  the  rotating  power  SV^  x  amxi6,  should  be  of  the  form 
a  Biji  $  -^  h  cos  6,  As  in  this  case  a  and  b  cannot  be  separated  by  any 
experimental  process,  it  will  be  best  to  make  a  include  the  functions 
of  0,  which  express  the  rotation,  so  that  the  power  to  turn  the  cup 
shall  be  Sa^  ;  and  this  in  general. 

Secondly.  Putting  the  opposite  cup  in  its  place,  while  the  concave 
of  the  first  moves  from  the  wind  the  convex  moves  against  it,  and 
meets  a  resistance  =  Saf£f*  (2,)  The  co-efficients  a  and  a',  are  diffe- 
rent functions  of  0.  When  it  is  90,  I  determined  their  ratio  to  be 
4*011 :  on  either  side  of  this  the  ratio  is  greater,  though  the  absolute 
values  are  less.  Both  positive  and  negative  pressures  are  increased  a 
little  hj  the  so-called  friction  of  the  passing  air.  Since  this  acts  by 
producmg  eddies,  it  may  be  expected  to  vary  as  ^  vaad  R^ :  indeed, 
Mr.  Fronde  has  shown  that  in  the  case  of  water  it  is  as  the  square  of 
the  relative  velocity.     Here  its  influence  must  be  very  small. 

Thirdly.  There  are  two  resistances  as  t^',  which  may  be  grouped 
together.  The  first  of  them  is  the  amount  of  power  expended  in 
throwing  outwards  the  air  in  the  Anemometer's  track  by  centrifugal 
force,  as  in  a  blowing  fan ;  this  will  be  probably  as 

28W 


I  measured  its  amount  in  quiescent  air,  by  making  two  cups  similar  to 
those  of  my  instrument,  and  with  the  same  length  of  arm,  revolve 
with  various  velocities,  by  weights  acting  on  a  thread  coiled  on  their 
axles,  whose  pull  at  their  centres  was  measured.  When  the  concaves 
moved  foremost,  I  thus  obtained  Obo  ;  when  the  convex  On  -f  & ;  and  as 
I  had  found  the  ratio  of  a^  and  af^  ^  4*011,  h'  was  found  to  be 
tf'io  X  0,  9535.  Whether  it  will  have  the  same  value  in  moving  as  in 
quiescent  air  is  uncertain ;  the  escape  of  air  against  the  wind  will  be 
impeded,  but  will  be  accelerated  with  it,  so  that  the  above  mode  of 
computing  it  may  be  provisionally  assumed. 

The  other  part  of  this  resistance  is  one  arising  from  the  motion  of 
the  convexes  against  the  air  independent  of  the  wind,  which  is  still 
more  difficult  to  estimate.  At  0  =  0  or  180,  they  move  at  right  angles 
to  the  wind,  and  are  resists  as  if  it  were  null,  therefore  as 

2Si^nXf^; 

at  90  and  270,  this  action  (as  separate  from  that  of  V)  vanishes  ;  at 

*  It  ifl  poemble  tliat  eddiM  from  the  following  convex  may  reach  into  the  coa- 
cave,  and  increase  the  force. 


436  Proceedings  of  the  Royal  IrUh  Academy. 

intermediate  positions  its  amount  is  doubtful.  There  will  be  some 
duo  to  the  component  of  v  perpendicular  to  F,  and  some  to  that  part 
of  the  convex  which  is  not  reached  by  R  or  R. 

The  combined  effect  of  these  and  the  centrifugal  resistance  may  be 
put  =  Sbv", 

Fourthly.  The  last  resistance  is  friction,  which  may  be  of  three 
kinds.  It  is  independent  of  the  relative  velocity  of  the  rubbing  sur- 
faces, but  is  as  their  pressure. 

(1).  In  the  ordinary  use  of  the  Anemometer,  its  axis  is  vertical  and 
the  friction  due  to  its  weight  is  constant ;  this  is  easily  measured  by 
attaching  weights  to  a  thread  passing  over  a  pulley  (whose  friction  is 
known),  and  coiled  on  its  axle  or  a  cylinder  fixed  on  it  of  known 
radius  =  p,  till  it  just  moves  on  tapping.  This  weight  multiplied  by 
e.  is/.     (2).  The  pressure  of  the  wind  on  the  cups  is  another  cause  of 

friction  by  pressing  the  axle  against  the  upper  bearing.  As  in  perma- 
nent rotation  the  impelling  =  the  retarding  forces,  and  they  balance  at 
the  axle,  the  pressure  there  =  their  sum,  or  twice  the  impelling  force. 
This,  as  is  evident  from  equation  (I.)  =  (a  -  a')  x  ( F*  +  r').  Let/"  be 
the  friction  due  to  a  unit  pressure  X  to  the  axis,  then  this  friction 
=  2  fa  ( F'  +  r').  The  effect  of  this  is  simply  to  substitute  for  a  in  (II.) 
a  (1  -  2/^).  It  therefore  need  not  be  taken  into  account,  as  it  will  be 
included  in  any  determination  of  that  co-efficient.  The  pressure  will 
be  something  greater  than  the  above  from  resultants  in  the  direction 
of  the  arms,  but  since  these  also  are  as  F'  they  do  not  alter  the  result. 
(3).  When  an  Anemometer  is  carried  by  a  whu*ling  machine,  its  move- 
able pai:ts  are  urged  outwards  by  centrifugal  force,  which  produces 
pressure  on  its  bearings  and  therefore  friction.  Let/^,  be  the  friction 
due  to  a  unit  pressure  parallel  to  the  arm  A  of  the  whirling  machine  ; 
P  the  centrifugal  pressure  due  to  the  unit  F 

W      G 

IF  being  the  weight  of  the  moving  parts,  and  G'the  distance  of  their 
CG  from  the  centre  of  the  whirler ;  then  /,,  P  F*  is  the  centrifugal 
friction  ;  this  is  equivalent  to  multiplying  a  by  (1  -  f,„  P)  and  need 
not  be  computed.  But  the  a  ofund  by  a  whirling  machine  must  be 
divided  by  this  factor  to  make  it  apply  to  real  wind  measurement. 
Combining  these  four  forces,  and  putting  for  R  and  R*  their  values, 
we  obtain  for  the  moving  force  in  the  position  0, 

-  T.(a^^afAv^-2rv\a^^'<:^^«iJi6-  (I.) 

If  we  have  a  series  of  values  of  fl^and  a'^  through  the  arcs  on  which 


Robinson — On  the  Cup  Anemometer.  437 

they  have  poBitive  values,  we  can  get  their  mean  values.    For  a  and  (^ 

this  value  =  = ,  ^  and  6^'  being  the  limits  between  which  a  is  posi- 


tive ;  for  the  second  co-efficient  it  = 


The  integration  is  easily  done  by  quadratures,  and  the  mean  values 
must  he  taken,  I  then  gives 

oF»-2)3,x  rf;-t;»xy-/=0,  (II.) 

which  coincides  inform  with  my  original  equation,  the  chief  difference 
being  in  y. 

Adding  a  second  pair  of  cups  at  right  angles  to  the  former,  the 
forces  are  all  doubled,  except/:  that  is  increased  by  the  increased 
weight  of  the  cups  and  their  arms ;  but  the  friction  due  to  the  weight 
of  the  axle  and  to  the  registering  apparatus  is  unchanged.  This  should 
always  be  measured  as  before  described.  With  four  cups  the  motive 
force  is  more  uniform  than  with  two,  and  the  period  of  its  variations 
is  half  that  of  the  other. 

Solving  this  quadratic,  we  have 


jr 
Calling  —  =  m' ;  if/  were  to  vanish, 

V 

m=J^lJ-.  (IV.) 

\  a'     a     a 

This  value  of  m  is  independent  of  the  size  of  the  instrument,  except  as 
relates  to  the  part  of  y  which  depends  on  centrifugal  force,  unless  it  be 
so  small  that  the  impulse  on  one  cup  interferes  with  its  neighbour ;  it  is 
also  independent  of  v.  The  correction  for  an  instrument  which  records 
F  as  mi'  is  hence  easily  found ;  f or  if  i»'  =  m  +  ft,  we  have  F=  mv-^fjuo; 
fiv  is  therefore  the  correction.     Now 


(— !J-(-0*^ 


hence 


■Hif 


or' 


(-?)T 


■S?*-"!       <■"■'> 


43A  Proceedingi  of  the  Boyal  Iri$h  Academy, 

This  decreases  as  v  increases,  and  vanishes  when  it  is  indefinitelj 
increased. 

Then  comes  the  question,  how  are  these  co-efflcicnts  to  be  deter- 
mined ?  Not,  I  fear,  by  any  observations  with  actual  wind,  for  none 
of  the  methods  which  have  been  proposed  to  measure  its  velocity  are 
satisfactory.  I  should  prefer  determining  them  by  immersing  the 
Anemometer  in  a  stream  of  water,  were  it  certain  that  the  elasticity  of 
the  air  makes  no  difference.  But  here  also  the  velocity  of  the  current 
varies  in  different  parts*  of  its  section,  and  should  be  meaned  through 
that  part  occupied  by  the  instrument.  Such  experiments  would  be 
very  desirable,  when  fit  opportunity  could  be  obtained ;  but  this  is  not 
easily  found,  and  we  should,  in  the  first  instance,  try  to  get  from 
the  whirling  machine  iU  best  pw9%hle  rendU,  which,  I  think,  with 
proper  precautions,  will  be  far  better  than  those  which  M.  Dohrandt 
was  able  to  obtain  under  the  conditions  of  his  experiments.  I  will 
therefore  point  out,  fir%t^  the  mode  in  which  it  and  the  Anemometer 
connected  with  it  should  be  constructed ;  and  secondly,  the  way  in 
which  I  think  it  should  be  employed. 

To  begin  with  the  whirling  machine : — ^It  must  combine  a  strong 
framing  with  facility  for  transport,  since  it  should  be  used  in  a  room 
of  large  dimensions ;  and  such  are  generally  employed  for  public  ob- 
jects,  from  which  they  cannot  be  long  diverted.  The  framing  should 
therefore  be  easily  taken  asunder.  I  think  it  essential  that  the  cups 
in  their  rotation  ^ould  not  be  nearer  than  ten  feet  to  ceiling,  walls,  or 
floor.  This,  if  the  arms  of  the  Ant mometer  be  two  feet,  will  require 
the  horizontal  arm  to  be  twelve  feet  from  the  ground.  Its  length 
should  be  as  great  as  the  locality  permits,  in  accordance  with  the  above 
conditions.  If  too  short,  there  woxdd  be  a  difference  of  pressure  on  the 
inner  and  outer  sides  of  the  cups,  which  might  distiirb  the  results.  X 
think  eight  feet  would  be  sufficient.  A  single  arm  with  a  counter- 
poise alone  is  required.  The  arm  (and  all  that  it  carries)  should  pre- 
sent as  little  resistance  to  the  air  as  possible.  That  which  I  used  was 
made  of  sheet  iron  ^  inch  thick,  filed  to  sharp  edges,  and  made  inflexible 
by  ties  of  steel  wire  attached  to  the  top  of  the'  axle.  It  was  only  two 
feet  long ;  but  the  same  construction  will  be  fully  available  in  the 
present  instance.  The  vertical  axle  is  a  tube  strong  enough  to  resist 
the  driving  force ;  it  turns  in  collars,  one  at  the  top  of  the  frame, 
another  carried  by  cross-pieces  about  two  feet  from  the  ground.  This 
last  has  a  disc,  on  which,  by  means  of  three  balls,  or  by  conical  rollers, 
and  a  flange  attached  to  the  tube,  this  latter  revolves.  This  perfora- 
tion of  the  axle — an  idea  for  which  I  am  indebted  to  Mr.  Grubb-— 
simplifies  greatly  the  mechanism  of  the  apparatus. 

A  cord  passing  to  the  brake-lever  of  the  Anemometer  over  a  pulley 
at  the  top  of  the  tube-axle  supports  an  inner  tube,  adjusted  central  to 
it  by  guides.     This  tube  carries,  below  the  axle,  a  stage  on  which  cir- 


*  An  to  this  see  page  430,  not*. 


Robinson — On  the  Cup  Anemometer.  439 

cular  weights,  tip  to  10  or  12  lbs.,  can  be  placed;  below  wbicb  is 
attached  a  conical  yessel  to  receive  shot  for  small  additions  of  weight, 
which  can  be  removed  by  a  valve  at  its  bottom. 

It  is  important  that  the  machine  shall  be  capable  of  being  driven 
with  a  uniform  speed  of  any  amonnt,  which  can  be  gradually  increased. 
This  may  best  be  effected  by  the  descent  of  a  weight  connected  with 
the  axle,  and  continually  wound  up  by  means  of  an  arrangement  like 
the  well-known  contrivance  of  Huyghens.  The  velocity  can  be  increased 
by  adding  to  the  weight.  At  the  speed  of  25  miles  per  hour,  the 
maximum  resistance  to  the  cups  would  be  about  2  lbs.,  and  the  power 
expended  that  of  75  lbs.,  falling  1  foot  in  a  second.  This  is  only  }  of 
a  man's  power. 

The  Anemometer  to  be  used  in  connexion  with  this  machine  should 
also  present  as  little  resistance  to  the  air  as  possible.  For  this  pur- 
pose its  frame  should  consist  of  a  strip  of  sheet  iron,  twice  bent  at  right 
angles.  The  uprights  so  formed  should  have  bearings  for  the  axle, 
which  must  be  set  parallel  to  the  arm  of  the  whirling  machine,  and 
need  not  be  more  than  6  inches  long  and  ^  inch  in  diameter.  The 
cross  of  the  Anemometer  is  fixed  to  its  outer  extremity  :  this  should, 
in  the  first  instance,  be  of  the  Kew  type,  cups  of  9  inches,  and  the 
track  of  their  centres  48  diameter.  On  the  axle  is  secured  a  brass  disk, 
6  inches  diameter,  on  whose  circumference  acts  a  circular  brake,  one 
lug  of  which  is  screwed  firmly  to  the  bottom  of  the  frame,  the  other 
one  is  pressed  towards  it  by  the  short  arm  of  a  right-angled  lever, 
turning  on  a  centre  similarly  secured,  and  its  l(Higer  arm  connected 
with  the  cord  coming  from  the  whirling  machine.*  It  is  evident  that 
by  placing  weights  on  the  stage,  we  can  apply  considerable  pressure 
to  the  brake,  and  thus  increase  the  Anemometer's  friction  without  at 
all  interfering  with  the  whirl.  Any  of  these  frictions  is  easily 
measured.  Let  the  mouth  of  a  cup  be  horizontal ;  place  small  weights 
at  its  centre  till  it  just  moves  on  slightly,  jarring  the  frame  as  by 
light  taps,  or  drawing  a  float  over  it.  Bepeat  this  for  the  other  cups, 
and  take  the  mean.  This  force  is  less  than  what  is  required  to  start 
them  from  a  state  of  rest,  but  it  corresponds  to  that  which  will  exist 
during  the  rotation  of  the  machine.  I  expect  it  will  be  found  that  the 
friction  will  be  constant  for  a  given  load  on  the  stage.  The  centrifugal 
friction  may  be  determined  by  attaching  to  the  outer  end  of  the  Anemo- 
meter axle  a  thread,  pulling  in  its  direction  over  a  pulley  of  known 
friction,  apply  to  it  a  weight  =  P.  and  measure  the  friction ;  the  excess 
of  this  over  the  normal  friction  divided  by  P  =  /,^.  As  it  is  desirable 
that  the  normal  friction  should  be  kept  as  low  as  possible,  the  axle 
should  rest  on  vertical  friction  wheels,  and  a  horizontal  one  bearing 
on  the  back  of  the  brake  disk  will  lessen  the  centrifugal  one.     For  a 


*  Mr.  Gmbb  suggests  that  the  brake  apparatus  should  be  brought  close  to  the 
vertical  axis,  and  the  axle  of  the  Anemometer  lengthened  This  would  materially 
lessen  the  disturbance  of  air  caused  by  the  whirl,  and  the  centrifugal  friction. 


440  Proceedings  of  the  Royal  Irish  Academy, 

purpose  to  be  soon  mentioned,  this  disk  should  have  on  one  face  a 
graduation  ;  to  5^  will  be  sufficient. 

Both  the  whirling  machine  and  the  Anemometer  should  be  pro- 
vided with  electric  registration  in  some  form.  For  instance,  springs 
of  platinum  attached  to  their  axles,  and  making  at  each  revolution 
contacts  actuating  small  electro-magnets  depressing  pens  to  make  dots 
on  a  cylinder  covered  with  paper  and  driven  by  a  clock.  Either  the 
cylinder  or  penholder  must  have  a  transverse  motion,  so  that  the  dots 
may  be  arranged  in  helices  if  the  experiment  should  last  for  more  than 
one  revolution  of  the  cylinder.  If  the  circiunlerence  of  the  cylinder 
and  the  time  of  its  revolution  be  known,  these  will  probably  give  the 
time  with  sufficient  accuracy  to  compute  V.  It  need  scarcely  be  said 
that  time  must  be  allowed  for  the  whirl  to  become  uniform  before  the 
register  is  made  to  act. 

The  most  obvious  mode  of  using  this  apparatus  to  determine  the  co- 
efficients is  similar  to  that  used  by  M.  Bohrandt ;  but  using  the  equation 
(II.),  and  measuring/,  and  obtaming  corresponding  values  of  Fand  p 
through  as  wide  a  range  as  possible.  Then  by  minimum  squares  obtain 
the  other  co-efficients.  I  do  not  like  this,  because  it  gives  no  special  in- 
formation as  to  the  variability  of  the  co-efficients,  should  it  exist ;  and 
because  since  F,  except  for  the  very  small  values  of  r,  is  nearly  as  mr, 
neither  minimum  squares,  nor  common  elimination,  give  accurate 
results  without  carrying  the  calculation  to  a  large  number  of  decimals. 

The  co-efficient  a  may  be  determined  without  difficulty.    It=-^^ 

Vq  being  the  velocity  which  just  moves  the  Anemometer  from  a  state 
of  rest.  If  we  increase  the  speed  till  it  begin  to  move,  we  get  Fi. 
This  instant  may  be  observed  by  the  dropping  of  a  disk  of  eard,  held 
by  friction  against  a  stop,  or  by  employing  the  electric  register  of 
the  Anemometer  (which  is  not  wanted  here),  to  ring  an  alarm.  One  of 
the  cups  should  be  set  by  means  of  the  graduation  on  the  brake  disk 
to  0  =  0,  then  to  5,  10,  &c.,  to  90 ;  and  the  mean  should  be  taken 
through  the  quadrant  to  give  a.  Then  the  friction  should  be  increased 
and  the  a  obtained  for  higher  values  of  Vq.  Should  these  agree  with 
the  former,  this  co-efficient  is  independent  of  F;  if  not,  their  relation 
can  be  found  and  (II.)  modified  accordingly.* 

As  to  the  other  co-efficients,  I  have  already  said  that  the  process  of 
miTiimnni  squares  is  not  satisfactory  on  account  of  the  small  variation 
of  w'  in  a  series  of  ordinary  observations.  But  our  apparatus  enables 
us  by  increasing /to  increase  m'  to  any  extent.     Put  (II.)  in  the  form 

-2i8i»'-y-4  =  0.  (^0 

fr 


am 


•  Perfect  agreement  is  not  to  be  expected ;  for,  as  ab^ady  remarked,  the  velocity 
of  the  whirling  machine  gives  only  approximately  the  action  of  the  air  on  the 
eups ;  and  the  difference  "wm  increase  with  the  8];)eed. 


BoBiNSON — On  the  Cup  Anemometer.  441 

HaTing  thiee  such  eqnationa  with  different  values  of  /  and  v, 
we  can,  of  course,  find  the  three  co-e£Elcient8  with  much  greater  pre- 
cision. It  is  desirahle  that  F  should  be  unvaried  for  the  three  ohser- 
vationsy  to  avoid  its  influence  on  the  result.  Here,  also,  taking  -Fas 
large  as  possihley  several  such  triplets  may  be  obtained ;  and  if  they 
all  give  tiie  same  results  the  co-efficients  are  independent  of  v. 

Should  a  be  shown  by  experiment  to  be  constant,  the  co-efficients 

S    y 

-,  -,  are  eaidly  obtained ;  for  two  of  the  above  equations  give 


{-^^■S-£-''^ 

a                       m"-m"  a                 a 

f 

(VII.) 

If  this  work  should  show  that  additional  powers  of  F  or  f?  must 
be  introduced  into  (11.),  m  will  not  be  constant,  and  the  instrument 
should  be  constructed  to  show  not  mv,  but  v ;  and  a  table  of  V  should 
be  computed  with  v  as  argument  which  would  serve  for  all  Anemo- 
meters of  the  same  type. 

Having  fully  examined  this  Anemometer,  others  should  similarly  be 
tried,  varying  in  the  size  of  cups  and  arms ;  and  this  will  show  whether 
a  and  y  are  exactly  as  the  area  of  the  cups,  whether  the  eddies  caused 
by  one  cup  interfere  with  the  motion  of  that  which  follows  it,  and 
whether  tiiere  be  any  maximum  relation  between  the  cups  and  arms, 
and  how  y  varies  with  the  latter: 

AU  this,  however,  rests  on  the  assumption  that  the  F  given  by  the 
whirling  machine  acts  similarly  to  an  equal  one  of  real  wind.  I 
think  that  most  of  the  defects  of  M.  Dohrandt's  apparatus  may  be 
avoided,  except  the  difference  between  the  action  of  a  quiescent  and  a 
moving  fluid.  Yet  if  this  were  determined  in  water  for  a  cup  ex- 
posed perpendicularly  and  at  45,  for  the  concave  and  convex  surfaces, 
it  is  highly  probable  that  we  should  be  able  to  reduce  with  sufficient 
precision  the  results  of  the  machine  to  those  of  the  wind.  Should 
any  further  experiments  like  those  of  Mr.  Froude,  already  referred  to, 
be  undertaken,  I  hope  this  question  will  not  be  lost  sight  of. 

There  are  two  other  differences ;  the  Anemometer  must  produce 
eddies  in  the  air  which  in  the  case  of  wind  are  swept  away  from  the 
instrument ;  but  when  it  travels  in  confined  space  they  may  con- 
tinue till  in  the  course  of  its  revolution  it  returns  into  them.  It  is  not 
easy  to  predict  their  effect  or  ascertain  how  long  they  last.  The 
circular  current  established  in  M.  Dohrandt's  work  will  probably  (if 
produced  at  all)  be  insignificant  in  a  freer  space  and  better  constructed 
apparatus.  It  ma^  be  best  examined  by  stopping  the  whirl,  and  at 
the  instant  projecting  smoke  into  the  track  of  the  Axiemometer.  Useful 
information  on  this  point  might  be  obtained  by  attaching  to  the  revolv- 
ing arm  a  small  rectangle  of  sheet  iron  inside  the  Anemometer  so  as 
to  increase  its  resistance  and  observing  what  change  this  produces  on  v. 

a.  X.  ▲.  noc.f  SIB.  n.,  vol.  n.,  sciikci.  3  A 


442  Proeeedingi  of  the  Boyal  IrUh  Academy, 

If  we  might  aasome  the  a  observed  as  above  to  represent  that  be- 
longing to  rral  wind  f and  especiallj  when  f onnd  with  a  low  velocity 
of  whirl  when  the  eddies  most  be  small),  we  eonld  obtain  P  and  y  by 
iti  action.  Let  the  Anemometer  above  described  be  detached  from  the 
whirling  machine  and  placed  in  open  air  with  its  axle  vertical,  axid 
near  it  another  as  a  standard,  having  its  cnps  and  arms  of  the  same 
dimensions.  They  will  have  the  same  a,  p  and  y,  and  the  same  un- 
known Fmay  be  sapposed  to  act  on  both. 

The  observations  of  v  with  the  two  must  be  synchronous,  and  calling 
m'  that  belonging  to  the  standard,  m"  and  m'"  those  belonging  to  the 
other  with  two  different  values  of/  obtained  by  hanging  weights  to 
the  longer  arm  of  the  brake  lever,  we  have,  as  k  is  given, 

V 

and  by  (VII.) 

0,8  F  F' 

—  =  »i'(»4  1) r rT-l»(»'+l) JJ-, r^, 

a  '     i»'(n-l)        ^  '      «'(»'- 1)' 


fn"= o«m';  m"''^n'm\ 


whence 


Knowing  m'  we  have 


r,  ^,  and  ^. 

a  a 


The  difference  of  these  values  from  those  given  by  the  whirling 
machine  will  show  how  far  the  latter  method  can  be  relied  on  in  this 
inquiry. 

To  avoid  the  irregularities  already  referred  to  as  caused  by  local 
circumstances,  the  cups  of  the  two  instruments  should  be  at  the  same 
height  above  the  ground,  their  placement  should  be  quite  open,  and 
their  position  occasionally  interchanged.  But  the  wind  itself  is  irre- 
gular to  an  extent  of  which  I  had  no  idea  till  I  examined  the  pressure 
curves  from  which  I  deduced  the  a  of  my  Anemometer.  In  one  of 
them  whose  time  was  only  99  seconds,  the  force  at  the  axle  varied 
from  26  to  9  pounds,  andin  none  of  them  was  it  nearly  uniform.  Such 
'variation  will  affect  mf  and  m"  differently;  but  possibly  the  mean 
results,  especially  if  each  experiment  lasts  for  several  minutes,  will 
not  be  much  astray. 

I  think  it  may  be  expected,  with  some  confidence,  that  the  line 
of  research  which  I  have  indicated  will  lead  to  useful  results,  both  in 
theory  and  practice,  and  give  values  for  these  constants,  which,  if  npt 
absolutely  exact,  will  be  a  close  approximation  to  the  truth.  The 
experiments  which  I  propose  would  not  be  very  costly  if  the  appara- 
tus were  not  constructed  for  permanent  use ;  and  I  am  not  wiUiout 
hopes  that  I  may  myself  be  enabled  to  execute  them. 


KiXAiiAN — Tiilal  Currents  and  Wind-trarcH.  443 


XL. — The  DBnrriifG  Poweb  of  Tidal  Ctjbkexts  versus  That  op  Wno)- 
WAVES.    By  G.  H.  Kinahaw,  M.  E.  I.  A.,  &c. 

[Bead  November  dOth,  1875.] 

It  might  have  been  supposed  that  the  exhaustive  report  on  "Waves, 
bj  J.  Scott  EuBscll,  E.  E.  S.,  &c.,*  should  have  decided  the  relative 
merits  of  the  tidal  currents*!  and  wind- waves  in  regard  to  their  drifting 
powers.  This,  however,  seems  not  to  be  the  case,  if  we  may  judge 
from  the  recent  paper  on  the  Chesil  beach,  Dorsetshire,  read  by  Pro- 
fessor Prestwich,  before  the  Institution  of  Civil  Engineers,  Feb.  2nd, 
1875,  and  the  discussion  that  followed  the  reading  of  it. 

In  the  report  above  mentioned,  Scott  Eussell  divides  waves  into 
four  orders.  To  the  first  of  these,  or  the  TTave  of  Translation^  belongs 
the  great  tidal  wave ;  while  wind- waves,  according  to  that  observer, 
with  a  certain  limitation,  belong  to  the  second  order,  the  limitation 
being,  that  those  wind- waves  that  are  in  the  act  of  breaking  on  a 
beach  change  into  waves  of  the  first  order.  Indirectly,  however,  the 
wind  forms  a  different  order  of  waves,  for  if  water  is  piled  up  in  a 
narrow  by  the  wind,  the  waves  induced  are  **  waves  of  translation." 
Scott  Eussell  also  proves  that  a  wave  of  the  second  order  has  little  or 
no  carrying  power ;  consequently  wind- waves  can  have  little  of  this, 
except  when  actually  running  up  the  beach,  when  they  change  to 
''  waves  of  translation ;"  and  even  there  their  action  is  limited  to  a 
quite  narrow  line. 

In  a  tideless  sea,  wind- waves  breaking  on  the  coast  line  form  con- 
siderable and  permanent  banks,  as  in  the  Mediterranean,  where  the 
detritus  brought  down  by  the  Ehone  is  piled  up  during  storms  on  the 
neighbouring  shores,  forming  banks  and  lagoons.  Considerable  wind- 
wave  action  also  will  be  found  in  freshwater  lakes  and  in  brackish- 
water  lagoons,  if  in  the  latter  the  cross  tides  counteract  one  another ; 
but,  as  far  as  my  experience  goes  in  the  seas  round  Ireland,  the  wind- 
waves  do  very  little  permanent  work,  if  unaided  by  the  tidal  currents.  If 
wind-waves  did  effect  permanent  driftage,  it  ought  to  be  apparent  on 
the  coast  lines,  the  direction  of  its  movement  corresponding  with  that 
of  the  prevailing  winds  resolved  along  the  trench  of  the  coast.  The 
direction  of  the  prevailing  winds  is  {dways  registered  by  the  lean  of 
the  trees  on  a  coast  line,  while  the  course  of  the  driftage  is  marked  by 
the  sand  ridges  or  banks  forming  the  knee-shaped  invers  or  mouths 
to  the  streams,  the  inver  being  shifted  laterally,  in  the  direction  in 


•  "  Report  on  Waves,'*  Brit.  Absoc.  Reporta,  Vol.  xiii.  311,  1844. 

t  Tidal  CiirrentB  are  due  to  the  "  Flow  "  and  **  Ebb  "  of  the  tides ;  these  are 
quite  distinct  from  the  "  Rise  "  and  "  Fall  "of  the  tides.  This  subject  is  fully 
explained  in  the  tract  on  "  The  Tides  and  Tidal  Currents  of  the  Irish  Se«i  anil 
English  Channel,"  by  the  Rev.  S.  Haughton,  F.  T.  C.  D.,  &e.,  p.  3,  el  aeq, 

3A2 


444  Proceedings  of  the  Royal  Irish  Academy, 

which  the  driftage  tends ;  but  the  lean  of  the  trees  and  the  driftage  of 
the  beach  are  often  in  opposite  directions.  We  also  find  that  a  float- 
ing body,  such  as  a  ship  at  anchor,  always  swings  with  the  tide,  except 
in  a  very  excessive  gale;  and  fishei-men's  nets,  when  theybrec^  loose, 
always  drift  with  the  tidal  current ;  so  also  floating  timber  drifts  with 
the  tide,  unless  it  comes  so  near  the  shore  as  to  be  under  the  influence 
of  the  wind-waves,  after  they  have  changed  into  **  waves  of  transla- 
tion." 

The  study  of  the  tidal  currents  on  the  coast  of  Ireland  teaches  us 
that  they  have  little  or  no  driftage  power  when  the  tide  is  on  the  ebb, 
even  when  confined  in  narrow  channels ;  to  this,  however,  there  are 
exceptions,  as  the  quantity  of  water  flowing  out  through  a  channel 
may  be  considerably  increased  by  land  drainage,  thus  causing  the 
efflux  to  be  of  longer  duration  than  the  influx ;  in  some  places  the  tide 
runs  out  of  an  estuary  for  hours  longer  than  it  flows  into  it,  the  efflux 
being  augmented  by  floods  in  rivers,  and  the  like.  It  appears  also  that 
the  driftage  is  greater  during  spring  than  neap  tides ;  and  that  the 
maximum  driftage  occurs  when  the  direction  of  the  incoming  current 
is  the  same  as  that  of  the  prevailing  wind.  We  also  learn  that  the 
**  set"  of  the  tidal  current  in-shore  depends  very  much  on  the  shape  of 
the  coast  line.  If  the  coast  line  is  straight,  the  direction  of  the  set  of 
the  tide  along  the  shore,  and  outside  in  the  deep  water,  will  probably 
be  similar ;  but  if  the  coast  line  is  indented,  or  islands  lie  ofl  the  coast, 
in-shore  currents  back,  or  "  counter-tides,"  and  cross  currents,  will  bo 
induced,  which  form  off-shore  banks,  and  thus  lead  to  various  com- 
plications ;  large  rivers  may  also  form  counter-currents  and  off-shore 
banks. 

In  n  bay,  fig.  1,  let  the  normal  incoming  tidal  wave  run  in  the 


Fio.  !.• 

direction  of  the  arrow  A ;  this  forms  a  primary  current  from  the  head- 
land (a)  to  the  headland  {h\  but  from  it  in-shore  or  secondary  currents 
branch  off  into  the  bay,  in  the  directions  of  the  arrows  (c*,  c",  c*),  which 
seem  to  decrease  in  power  from  ^  to  c';  as  the  flow  of  tiie  primary  cur- 
rent is  usually  much  more  rapid  than  that  of  the  secondary,  the  tide 
outside  generally  comes  in  faster  than  in  the  bay,  consequently  we  often 


*  In  all  the  woodcuts  arrow  A  represents  the  direction  of  the  flow  tide, 
and  C  the  ebb  tide — while  the  arrows  B  and  D  mark  the  directions  of  effective 
wind?. 


KiNAHAN — Tidal  Currents  and  Wind-waves,  445 

find  that,  towards  the  end  of  the  flow  of  the  tide,  there  is  a  counter  in- 
shore tide  from  the  headland  (3),  in  the  direction  of  the  arrow  {d).  The 
figure  represents  a  regular  bay,  with  equal  headlands ;  but  in  nature 
we  often  find  the  shore  line  of  the  bay  more  or  less  irregular,  or  a  con- 
siderable river  flowing  into  it,  which  causes  various  complications  in 
the  set  of  the  secondary  currents  in  the  bay.  Let  us  suppose  one  head- 
land to  be  longer  than  the  other ;  if  the  first  headland  is  the  longer, 
off-shore  shoals  may  form  across  the  mouth  of  the  bay,  and,  after  they 
are  formed,  the  force  of  the  secondary  currents  seems  to  increase  from 
c*  to  <^,  fig.  1.  The  formation  of  shoals,  however,  seems  to  depend 
also  very  much  on  the  nature  of  the  rocks  forming  the  sea  margin  ; 
for  if  the  margin  of  the  bay  and  the  coast  up-stream,  or  in  the  direc- 
tion from  whence  the  tidal  current  comes,  are  of  hard  rocks,  there  may 
be  no  materials  to  form  shoals  out  of ;  while  if  the  margin  of  the  bay, 
or  even  the  coast  line  up-stream,  is  of  frail  materials,  there  will  be 
shoals  :  a  river  might,  in  some  places,  also  bring  down  materials  suffi- 
cient to  form  shoals ;  this,  however,  is  an  exceptional  case  in  Ireland. 
Or,  as  in  fig.  2,  a  third  headland  (c)  may  be  opposite  the  headland  (i), 
forming  a  narrow,  as  in  the  English  Channel  between  Portland  Bill  and 
Cape  la  Hogue,*  in  which  case  the  primary  current  (A)  seems  often  to 
strike  against  the  second  headland  (J),  while  the  secondary  currents 
increase  in  strength  from  d^  to  d^.  That  the  secondary  currents  vary 
in  power,  as  mentioned  above,  seems  proved,  for  the  following  reasons. 
In  such  a  case  as  that  represented  in  fig.  1,  the  beach  margining  the 
bay  is  made  up,  in  nearly  all  places,  of  materials  very  similar,  both  in 
quantity  and  size,  which  travel  round  the  beach  from  a  to  ^ ;  while  in 
fiuch  a  case  as  represented  in  fig.  2,  the  materials  forming  the  beach 


Fio.  2. 

increase  considerably,  both  in  quantity  and  size,  in  the  vicinity  of  the 
second  headland  (&),  while  the  major  portion  of  them  travels  across 


•  Here,  in  addition  to  the  narrow  in  the  sea,  the  force  of  the  current  is  increased 
as  it  approaches  Portland  Bill,  by  the  "  Nodal "  or  "  Hinge  line  "  of  the  Tides  in 
the  English  Channel,  being  immediately  east  of  Portland!— (iTaw^A^ofi,  on  "  The 
Tidfs^"  ^c,  pp.  22,  ft  aeq.)  To  this,  thus  augmented  current,  is  probably  due  the 
assorting  and  piling  of  the  gravel  and  shingle  of  Chesil  beach  on  the  east  side  of 
Lyme  Bay,  immediately  N.N.W.  of  Portland  Bill. 


446  Proceedings  oj  the  Boyal  IrUh  Academy. 

the  bay,  and  not  round  its  margin ;  being  sorted  in  their  raniage,  tho 
largest  going  furthest,  and  forming  a  shingle  beach  at  the  back  of  the 
Hocond  headland  (h). 

Banks  off  a  coast  line  are  connected  with  counter-currents,  but 
whether  such  currents  have  induced  the  banks  or  the  banks  the  cur- 
rents, it  is  hard  to  determine.  Off  a  head  will  be  found  the  end  of  a 
shoal,  or  shoals,  and  farther  up  the  coast,  at  a  second  headland,  often 
very  slight,  we  find  that  a  counter-current  has  been  generated,  which 
flows  back  along  the  coast  to  the  first  headland,  where  meeting 
the  current  in  the  opposite  direction,  both  flow  seaward,  forming  a 
''race,"  till  they  meet  the  "tail"  of  the  shoals.  Such  races  seem 
seldom,  if  ever,  to  form  bars  or  half -tide  banks,  although  they  sensibly 
affect  the  soundings.  The  genesis  of  the  **  counter-tides"  is  very 
obscure,  as  also  the  manner  in  which  they  finally  join  into  the  main 
tide. 

It  is  not  unusual  for  rocky  islands  off  a  coast  line  to  affect  the  run 
of  the  tides.  Such  islands  usually  lie  off  a  headland,  being  a  portion 
of  the  rocks  of  the  headland,  disconnected  from  it  by  denudation. 
Under  some  circumstances,  such  an  island  will  split  the  tidal  cur- 
rent, causing  a  portion  on  the  up-stream  side  to  form  a  counter-tide 
that  will  flow  backwards  along  the  coast  line  ;  while  from  the  main- 
land, toward  the  island,  a  half-tide  ridge  often  forms.  If  there 
are  many  islands  off  a  headland,  the  currents  may  be  much  more 
complicated. 

Off  the  iuver  or  mouth  of  a  large  river  a  bank  often  forms^ 
owing  to  the  driftage  of  the  tide  being  partially  stopped  by  the 
water  flowing  out  of  the  river ;  let  (^)  fig.  3  represent  such  a  bank. 


Fio.  3. 

In  this  case,  if  the  bank  is  only  covered  during  very  high  tides,  when* 
the  tide  begins  to  flow  into  the  estuary  (a)  there  will  be  a  current  run* 
ning  between  the  bank  and  the  shore,  in  the  direction  of  (<f) ;  but  after 
half  or  three-quarters  of  the  tide  has  come  in,  there  will  be  a  "  coun- 
ter-tide "  in  the  direction  of  {e) ;  while,  after  the  tide  has  turned,  and 
the  tidal  current  is  running  in  the  direction  of  the  arrow  (C),  there 
will  be  a  current  into  the  estuary  between  the  bank  and  the  shore, 
in  the  direction  of  the  arrow  {e) ;  and  this  latter  current  will  continue 


EiNAHAK — Tidal  Currents  and  Wind-wavea.  447 

until  the  tide  begins  to  flow  out  of  the  estuary,  which  in  some  cases 
(when  the  estuary  widens  considerahly  inside)  may  be  hours  after  the 
true  turn  of  the  tidal  wave.  If,  however,  the  bank  {li)  is  low,  after 
it  is  covered  (say  at  quarter  or  half-tide),  the  tide  will  flow  over  it  in 
the  direction  of  the  arrow  (/),  and  there  will  be  no  "counter-tide" 
in  the  direction  of  {e).  The  "  counter-tide  "  (c)  has  a  considerable 
drifting  power ;  its  effects,  however,  are  much  modified  by  the  after 
current  («).  From  this  it  will  be  seen  that,  if  the  bank  {h)  is  only  at 
times  submerged,  the  channel  {e)  between  it  and  the  shore  will  be  shal- 
lower than  if  the  shoal  is  covered  during  the  greater  portion  of  the 
flow  of  the  tidal  wave.  Other  driftages  take  place  in  connexion  with 
sach  a  bank ;  they  are,  however,  usually  so  slight  as  not  to  affect  the 
general  question,  besides  that  in  a  great  measure  they  modify  one 
another. 

It  has  been  already  mentioned  that  the  unaided  outgoing  tidal 
current  appears  to  have  little  or  no  drifting  power,  not  even  when  flow* 
ing  through  a  narrow,  where  we  find  the  seaweed-covered  stones  are 
rarely  moved.  This,  however,  may  be  more  apparent  than  real ;  for  if 
the  bottom  of  a  narrow  is  covered  with  shingle  or  coarse  gravel,  sea- 
weed may  grow  on  these,  and  prevent  them  being  disturbed ;  while,  if 
tiie  bottom  is  small  gravel  or  sand,  a  portion  is  carried  off  by  the  out- 
going tide.  It  seems,  however,  to  have  very  little  effect  on  mud,  and 
in  the  Irish  estuaries  the  detritus  brought  in,  or  forced  back,  by  the 
tide  is  usually  in  excess  of  that  carried  out.  This  is  very  apparent  in 
the  tidal  flats  and  banks,  where  the  tributaries  of  the  main  stream 
nearly  always  flow  into  it  up-stream,  as  shown  in  fig.  4,  where  ^,  h  are 
the  tidal  muddy  flats,  the  arrow  A  indicates  the  direction  of  flow  tides, 


Fio.  4. 

and  the  arrow  C  the  direction  of  ebb  tides — a  being  the  stream  when 
the  tide  is  out,  into  which  the  tributaries  (<?,  c,  e^  c)  enter  with  the 
direction  of  the  incoming  tide.  Even  in  some  places  the  bed  of  a 
large  river  will  be  banked  up  by  materials  brought  up  by  the  tide  and 
the  stream  forced  out  of  its  proper  course :  for  example,  the  Slaney, 
Co.  Wexford,  where,  at  the  point  of  Park,  a  mud  bank  has  accu- 
mulated, and  forced  the  bed  of  the  river  northward.     Such  tidal 


448  Proceedings  oj  the  Royai  Irish  Academy. 

occumnlations,  howeyer,  are  greatly  modified  dming  floods  in  the 
rivers,  as  a  large  freshet  may  effect  considerable  denudation  daring 
the  time  the  tide  is  out.  Considerable  denudation  can  also  be  effected 
by  artificial  means ;  for,  by  judicious  arrangement,  as  in  the  Boyne, 
counties  Louth  and  Meath,  the  tidal  waters  can  be  changed  into  cur- 
rents that  act  like  freshets  in  rivers. 

Scott  Eussell  has  shown  that,  at  the  centre,  a  "  wave  of  transla- 
tion" is  stronger  and  swifter  than  at  its  margins ;  somewhat  in  tiie 
same  way,  the  driftage  of  the  in-coming  tidal  wave  off-shore  is  usually 
much  stronger  than  it  is  in-shore.  This  is  a  fact  well  known  to  the  fishex- 
men,  who  often  dredge  and  fish  worked-out  ground,  rather  than  fish  fresh 
ground  further  out,  on  account  of  the  additional  labour  that  would  be 
incurred  in  the  latter  place,  consequent  upon  the  augmented  velocity  of 
the  tides.  In-shore,  if  there  is  a  wide  and  long  shelving  beach,  the 
driftage  effected  is  spread  over  a  large  expanse,  and  the  results  are  not 
very  conspicuous  or  easy  to  study.  This,  however,  is  not  the  case  on 
quickly-shelving  beaches,  where  the  driftage  solely  due  to  the  tidal 
wave  is  conspicuous,  as  when  there  is  not  a  breath  of  wind  blowing ; 
if  the  beach  is  composed  of  fine  sand  or  gravel ;  each  wave,  according 
to  its  intensity,  carries  up  numerous  particles  in  more  or  less  oblique 
lines.  The  major  portion  of  the  particles  go  up  and  come  down,  as 
represented  by  the  curved  arrows  {g  and  /,  fig.  5) ;  some,  however,  re- 


■ifl^Wtsf^T? 


Fio.  6.» 

main  behind,  and  eventually  reach  the  top  of  the  beach,  in  a  track 
somewhat  similar  to  that  marked  by  the  curved  arrows  (/,  f  and/"). 
In  a  mixed  beach,  most  of  the  fragments  go  with  the  ari-ows 
{g  and  g*) ;  but  many  of  the  larger  fragments  ascend  the  beach  in  the 
irregular  course  indicated  by  the  arrows  (/,  /'  and/"),  especially  dur- 
ing spring  tides ;  these  lodge  on  the  top,  and  form  a  more  or  less 
marked  gravelly  or  shingly  margin.  It  is,  therefore,  not  unusual  to 
find  a  sloping  beach  constituted  as  follows  : — ^Above,  at  the  margin  of 
high- water  of  spring  tides,  a  more  or  less  well-marked  terrace  or  accu- 
mulation of  coarse  gravel  or  shingle  (J,  fig.  6)  ;  at  the  high-water  of 


*  a  in  this  figure  represents  the  shore-line,  to  the  left-hand  the  three  perpendi- 
CQlar  black  lines  represent  artificial  groins. 


KiNAHAN — Tidal  Currents  and  Wind-waves.  449 

neap  tides,  a  second  (e) ;  this,  however,  is  small  and  temporary,  as  it 
is  obliterated  and  removed  during  springs.  Between  high  and  low- 
-water  of  neap  tides  {e  and  d ),  there  is  a  shelving  beach  of  gravel 
and  sand,  and  immediately  below  (^  is  an  accumulation  of  shingle 
or  coarse  gravel,  forming  the  base  of  the  steeply-shelving  beach; 
while  between  the  latter  and  the  line  of  lowest  spring  tide  is  a  flattish 
space,  often  composed  of  fine,  immoveable  sand,  the  outside  or  lower 
margin  of  the  regular-moving  beach  being  at  the  shingle  accumulation 
below  the  line  d.  On  the  slope  between  c  and  d  there  are  always  more 
or  less  large  isolated  fragments  scattered  about  the  surface ;  the  shingle 
at  by  except  under  peculiar  circumstances,  will  ordinarily  be  much  less 
in  quantity  than  at  d ;  the  latter  moves,  more  or  less,  every  tide,  while 
the  upper  accumulation  (b)  only  is  moved  during  springs.  After 
storms,  however,  patches  of  gravel  and  shingle  will  be  scattered  over 
the  slope  between  the  line  c  and  d. 

This  travelling  of  beaches  accounts  for  the  accumulation  of  shingle 
on  the  up-stream  side  (relatively  to  the  direction  of  drift  movement)  of 
an  artificial  groin,  which  stops  the  travelling  of  the  materials  of  a  beach, 
as  the  larger  fragments  ascending  a  beach  are  forced  to  travel  along 
the  courses  indicated  by  the  arrows  (A  and  »',  fig.  6),  and  are  prevented 
from  descending  by  the  groins,  while  the  smaller  particles  are 
sucked  out  by  the  backwash,  some  accumulates  in  the  space  above 
the  arrow  (A).  Or,  if  the  groins  are  at  considerable  distances  apart,  the 
materials  arc  assorted  by  the  offshoots  {k  and/;),  from  the  main  current 
(j),  the  larger  particles  going  with  the  latter.  Many  natural  groins 
act  somewhat  similarly,  but  as  some  run  out  into  deep  water  for 
greater  or  less  distances  beyond  the  margin  of  the  beach,  their  action  is 
not  alike  in  all  cases,  as  will  appear  from  the  following.  Usually  as  a 
beach  while  travelling  meets  with  a  natural  groin  (as  the  headland 
a,  fig.  6),  the  sand^  &c.,  is  sucked  out  to  sea  in  the  direction  of  the 
arrow  (ff),  to  be  driven  into  the  next  bay  obliquely  (A).  If,  however, 
the  bay  (e)  is  narrow  and  regularly  formed,  the  wash  will  be  directly 
in  and  out  (t  and  7),  and  in  such  bays  the  tidal  action  seems  to  tend  to 
accumulate  larger  beaches  than  in  more  open  bays.  If  there  is  a  suc- 
cession of  bays  (d,  tf,/,  &c.),  with  strands,  and  the  headlands  between 
them  (fl,  bf  c,  &c.)  are  formed  of  materials  not  easily  denuded,  there 
will  be  no  source  to  supply  shingle,  consequently  the  materials  in  the 
beaches  (k,  I,  m,&c.)  will  decrease  in  size  from  wear,  till  eventually  the 
beach  will  be  solely  composed  of  fine  sand,  without  shingle  or  gravel 
margins,  either  above  or  below  (b  and  d^  fig.  5).  This  refers  to  the  drift- 
age along  the  margin  of  the  coast ;  there  might,  however,  be  deep  sea 
driftage  of  coarser  material,  that  would  be  carried  obliquely  on  to  the 
coast,  that  may  modify  the  above  results ;  as  shingle  and  gravel  often 
are  carried  direct  from  one  headland  to  another,  although  very  far 
apart. 

So  far  the  driftage  considered  has  been  that  solely  due  to  the  tidal 
currents ;  their  action,  however,  can  be  modified  or  augmented  by  wind- 
waves.  Wind- waves,  as  shown  by  Scott  Russell,  axe  usually  waves  of  the 


450  Proceedings  of  the  Royat  Irish  Academy. 

second  order,  and  hare  no  drifting  power,  bnt  locally  they  may  be  wares 
of  the  first  order  or  **  wayes  of  translation ; "  also,  wind  may  pile  up 
water  and  form  *'  waves  of  translation."  Thnsina  continued  heavy  gale 
from  the  south,  the  wind  will  pile  up  the  water  in  the  Irish  Sea,  to  which 
piling  is  due  heavy  large  waves  that  break  on  the  east  coast  of  Ireland. 
In-coming  tidal  currents,  augmented  by  the  wind  blowing  in  the  same 
direction,  are  capable  of  doing  the  maximum  amount  of  driftage  on  a 
coast  line,  while,  if  the  wind  blows  adverse  to  the  in-coming  tidal 
current,  it  modifies  the  coast  work,  or  even  for  a  time  may  wholly  stop 
it.  Adverse  wind  and  tidal  waves  pile  the  gravel  and  sand  on  a  beach 
in  transverse  sloping  ridges.  If  the  wind  and  tide  are  equal  the  ridge 
will  be  regular ;  if  the  tide  is  greatest,  the  top  of  the  ridge  will  slope 
in  the  direction  the  tide  is  flowing,  while  the  upper  end  of  the  ridge 
slopes  with  the  direction  of  the  wind  if  the  latter  is  in  excess.  This 
ridging  of  a  beach  may  also  occur  under  other  circumstances,  for  the 
waves  of  translation  due  to  the  piling  of  water  by  wind  breaking  on 
a  coast  line  will  ridge  the  beach,  also  heavy  wind  blowing  against  an 
outgoing  tide  may  force  it  on  to  the  beach,  and  piles  the  latter  in 
ridges.  If  wind  and  tidal  action  are  contrary,  the  maximum  power  of 
the  wind- waves  seems  to  be  during  the  ebb  of  the  tide,  and  especially 
at  the  low- water  of  spring  tides,  when  they  root  up  portions  of  the 
sea  bottom  (between  d^  and  «,  fig.  5),  that  under  ordinary  circum- 
stances remains  undisturbed. 

If  there  are  continuous  heavy  gales  blowing  obliquely  to  the  in-com- 
ing tidal  wave  (in  the  direction  of  the  arrow  B,  fig.  6),  accumulations 


Fio.  6. 

of  sand  and  gravel,  due  to  the  wind  waves,  will  form  at  n  and  j?,  while 
accumulations  due  to  tidal  action  will  collect  at  o  and  q.  To  form  the 
accumulations  at  n  and  p,  continuous  gales  will  be  necessary,  while  a 
good  gale  of  forty-eight  hours*  duration  in  the  direction  of  D  will  carry 
tiiem  all  away ;  and  even  this  time  would  not  be  necessary,  but  that 
before  the  accumulation  at  p  can  be  carried  away,  that  at  q  must  be 
dissipated,  for  as  long  as  there  is  any  sand  at  ^,  it  will  be  carried  by 
wind  and  tide  to  j»,  and  so  prevent  the  latter  from  decreasing  in 
size. 


KiNAHAN — Tidal  Carrents  and  Wind-tcaves,  451 


S.E.  Coast  of  Ikeland. 

To  illustrate  the  foregoing,  the  following  statistics  on  the  south- 
east of  Ireland  (Charts  xiv.  and  xv.),*  are  given,  as  this  coast  has  been 
carefully  examined,  and  the  results  mapped. 

The  area  contained  in  these  charts  includes  the  south  coast  between 
Brattan  Head  and  Camsore  Point,  and  the  south-east  coast  between 
Camsore  Point  and  Wicklow  Head.  On  the  south  coast  the  normal 
set  of  the  in-coming  tidal  current  is  about  west  to  east,  on  the  south-east 
coast  from  about  south  to  north ;  while  on  the  south  coast  the  more 
prevailing  heavy  winds  are  from  about  the  south-west,  and  on  the  south- 
east coast  from  about  the  north-east.f  Commencing  towards  the  south- 
west, we  find  that  at  Tramore  Bay,  the  eastward  tidal  driftage  has  piled 
up  a  ridge  enclosing  a  lagoon  called  the  Back  Strand.  This  ridge  having 
grown  eastward,  until  its  farther  progress  was  stopped  by  the  rock- 
bound  coast  of  Brownstone  Head.  Such  a  coast  is  not  easily  denuded, 
and  seems  to  force  the  driftage  seaward  in  all  cases;  allowing  the 
mouth  of  a  lagoon  or  river  to  remain  permanent,  the  growth  of  a 
ridge  being  thus  stopped. 

We  next  meet  with  the  estuary  called  Waterford  Harbour ;  here 
a  lagoon  could  not  form,  for  although  the  eastward  driftage  has 
attempted  to  bar  it  across,  yet  on  account  of  the  lai*ge  efflux  of  water 
from  the  Suir,  Barrow,  and  Nore,  and  the  rock-bound  shore  of  Hook 
promontory,  which  prevents  the  channel  from  moving  eastward,  the 
detritus  carried  in  by  the  tidal  wave  is  carried  out  again  to  sea  during 
ebb  tides.  East  of  Wateiford  Harbour  is  a  large  bay  extending  S.W. 
and  N.E.,  bounded  on  the  N.W.  by  Hook  promontory,  and  on  the 
S.E.  by  the  Saltee  islands  and  Crossfamoge  Point.  Here  the  main 
tidal  current,  when  it  passes  Hook  Point  sends  a  secondary  current 
to  the  N.E.  to  Bannow  Bay ;  while  between  Hook  and  the  Saltees, 
other  secondary  currents  branch  off  running  N.E.  to  the  sound 
between  the  north  Saltee  and  the  mainland,  where  they  turn  to  the 
N.W.  into  Ballytiegue  Bay,  forming  a  counter-tide,  which  meets  the 
tide  from  Bannow  Bay  at  the  Keeragh  islands.     The  current  that 


♦  Admiraltv  Chart,  Sheet  xir.,  from  Brattin  Head  to  Wexford,  aurve^ed  by 
Commissioner  Frazer,  M.R.I.  A.,  1847 ;  and  Sheet  xy.,  from  Wexford  to  Wicklow, 
anrveyed  bv  Commiaaionf  r  Frazer,  in  1844,  and  in  part  re-surveyed  by  6taff-Com- 
miBsioncr  J.  R  Kef*r,  in  1873. 

t  Winds  from  the  S.W.  do  not  affect  the  S.E.  coast ;  winds  from  the  south  do  in- 
directly, as  they  pile  up  water  in  the  Irish  Sea,  while  the  winda  that  blow  from  the 
S.E.  OBLYe  the  greatest  effect  on  the  driftage.  On  this  S.E.  coast  from  Camsore  to 
Wicklow,  the  trees  lean  to  the  N.E.,  asthe  preTailing  winds  (from  the  S.W.)  haye 
full  power  across  the  low  lands  of  the  Co.  Wexford.  Although  these  winds  have 
such  an  effect  on  the  trees,  they  have  no  effect  on  the  denudation  of  the  coast,  the 
wind-wayee  generated  not  acting  on  this  coast  line.  This  accounts  for  the  most 
effective  wind-wayes  being  due  to  winds  that  come  in  an  opposite  or  transyerse  direc- 
tion to  that  of  the  preyailing  winds. 


452  rracccdinga  of  the  Royal  Insh  Academy. 

runs  N.E.  along  the  Hook  promontory  carries  fragments  of  the 
Hook  promontory  rocks  as  far  as  the  Keeragh  islands ;  it  has  also, 
in  part,  formed  a  lagoon  occupying  the  inside  portion  of  Bannow 
Bay,  a  considerable  ridge  of  blowing  or  "-^olian  drift"  having 
accumulated  as  a  ridge,  extending  from  the  headland  N.E.  of  Fethaid. 
This  ridge,  however,  cannot  extend  farther,  for  here,  as  at  Tramore 
Bay,  the  opposite  coast  (Bannow  Island)  is  rock-bound.  When  thia 
tidal  current  passes  Ingard  Point  it  runs  northward  to  the  opposite 
coast,  part  from  thence  going  N.E.,  and  part  S.W.,  to  the  gut  called 
Fethard  Bay,  the  latter  current  forming  a  ridge  or  bar  extending 
toward  the  8.£.  from  the  north  shore  of  Fethard  Bay. 

The  *'  counter-tide  "  which  runs  N.W.  from  Orossfamoge  Point 
has  a  con8iderable  driftage,  and  to  it  in  a  great  measure  is  due 
the  .^olian  sand-ridge,  over  six  miles  long,  which  separates  the 
lagoon*  called  the  Ballyteigue  Lough  from  the  open  sea.  The  coast 
opposite  the  end  of  this  ridge  is  of  drift,  easily  denuded,  consequently 
the  ridge  is  yearly  extending  westward.  Since  the  Ordnance  maps 
were  made  (1840)  it  has  grown  nearly  two  hundred  yards.  This 
seems  to  be  a  good  example  of  the  effect  of  tidal  currents,  pure  and 
simple,  as  the  moBt  continued  and  effective  winds  on  this  coast  are 
from  about  the  8.W.,  and  opposite  to  the  direction  of  the  driftage 
due  to  the  "  counter- tide." 

The  secondary  current  which  generates  the  counter-tide  just 
mentioned  runs  N.E.  along  the  N.W.  of  the  Saltees;  but  along 
the  S.E.  of  t}io8o  islands,  there  is  also  a  secondary  current  running 
in  a  nearly  similar  direction ;  these  meet  in  the  sounds,  between 
the  islands  and  the  mainland,  forming  "counter-tides,"  "races," 
and  half -tide  banks :  the  most  marked  of  the  last  is  called  St.  Patrick's 
Bridge,  and  extends  nearly  from  the  mainland,  a  little  east  of  Oross- 
famoge Point,  toward  the  north  Saltee  Island.  Between  this  bank 
and  Orossfamoge,  at  Kilmore,  a  pier  was  erected  to  shelter  fishing 
boats  from  the  8.W.  winds ;  the  anchorage,  however,  is  rapidly  fill- 
ing up,  on  account  of  the  tidal  driftage. 

In  the  bay  between  the  Saltees  and  Oamsore,  there  are  "  counter- 
tides,"  the  most  marked  being  due  to  an  in-shore  stream,  that  runa 
westward  from  Oamsore,  during  three-quarters  of  the  tide,  while 
during  the  other  quarter  the  current  runs  to  the  eastward.  These 
different  currents  cause  a  great  complication  in  the  driftage,  they 
also  seem  to  assist  the  wind-waves  considerably,  as,  during  storms 
from  the  southward,  the  ridges  enclosing  the  lagoons  called  Tacumshin 
and  Lady's  Island  lakes  are  moved  inland,  while  the  coast  line  in  places 
between  Kilmore  and  Oamsore  is  being  rapidly  denuded.  South 
of  Tacumshin  lake,  there  is  a  "  counter-tide"  running  eastward 
to  Kilturk  bank ;  this  drifts  the  bank  westward,  thus  causing  the 
natural  embouchure  of  the  lake  to  be  at  the  western  end  of  the  bank, 


•  This  In^oon  i^  now  for  the  iiio.-^t  iwirt  roolaimed. 


KiNAHAN — Tidal  Cun*ent8  and  Wind-tcavcs.  453 

as  marked  in  the  Chart  of  1847.  Since  then  an  artificial  cut  was 
made,  near  the  centre  of  the  bank,  but  in  subsequent  years  an 
attempt  was  made  to  reclaim  the  lagoon,  and  this  cut  was  replaced 
by  a  tunnel.  The  reclamation  and  tunnel,  however,  have  failed, 
and  now  the  natural  opening  is  gradually  again  forming  at  the  western 
end  of  the  bank.* 

On  the  S.E.  coast  between  Camsore  and  Greenore,  the  driftage 
seems  to  bo  regularly  northward  along  shore ;  but  after  the  latter 
point  is  passed  there  are  two  lines  of  driftage,  the  main  driftage 
direct  towards  Cahore  Point,  and  a  secondary  driftage  round  Greenore 
Point,  and  along  the  shore  of  Ballygeary  Bay  to  the  Dogger  bank. 
There  is  also  at  times,  in  all  the  bays  on  this  S.E.  coast,  a  drift- 
age direct  on  shore,  occurring  after  continuous  south  gales,  and  appa- 
rently due  to  the  water  being  banked  up  in  the  Irish  Sea  by  the  wind. 
That  the  two  first  mentioned  tidal  driftages  occur  is  quite  palpable,  as 
portions  of  the  rocks  forming  the  coast  at  Camsore  and  (h'eenore  arc 
found  along  the  shore  of  Ballygeary  Bay  as  far  as  the  Dogger  bank, 
also  in  the  shingle  beach  which  margins  the  coast  for  three  miles  on 
the  south  of  Cahore  Point,  while  between  the  Cahore  shingle  beach 
and  the  Dogger  bank  they  are  very  rare.  Such  pieces  must  come  from 
Greenore,  and  not  from  the  local  drift,  as  all  fragments  and  blocks  in 
the  drift  have  come  from  the  northward  or  north-eastward,  and  not 
from  the  southward.  If  we  trace  the  beach  driftage  from  Greenore 
we  find  in  various  places  along  the  shore  a  little  shingle,  which 
increases  in  quantity  and  size  as  we  approach  the  Dogger  bank  ;  on  to 
which,  and  from  its  N.E.  end  north-eastward  to  the  Blackwater  bank, 
in  the  deep  water,  most  of  it  seems  to  be  carried.  Some,  however, 
goes  through  the  Hantoon  channel,  between  the  Dogger  bank  and  the 
Rosslare  sand  ridge,  a  small  portion  of  which  is  carried  round  the 
north  end  of  that  ridge,  to  be  lodged  on  its  west  side.  In  Ballygeary 
Bay,  a  pier  and  viaduct  was  commenced  in  1873.  This  has  now  quite 
changed  the  features  of  the  coast-line  on  the  east  of  the  pier,  as  a  fore- 
shore has  formed  between  the  old  cliff  and  the  sea.  This  accumula- 
tion extends  from  the  pier  to  the  Point  of  Ballygillane,  is  over  100 
yards  wide,  and  in  places  over  eight  feet  deep. 

The  efflux  from  the  "Wexford  lagoon  stops  the  tidal  driftage  to  the 
northward,  and  thus  forms  the  Dogger  bank ;  and  formerly,  prior  to 
the  in-take  of  a  considerable  portion  of  this  lagoon,  this  driftage  accu- 
mulated in  a  massive,  irregular  east  and  west  tidal  shoal,  as  repre- 
sented in  the  chart  made  in  1847  by  Comm.  Fraser,  R.  N.  ;f  showing 
that  the  force  of  the  efflux  and  of  the  tidal  wave  was  nearly  equal. 


*  Since  the  abovo  was  written,  the  occupies  of  the  adjoining  lands  have  cnt  the 
bank  near  the  fofmer  artificial  embouchure. 

t  Admiralty  Chart,  Sheet  xir.,  a.  d.  1847,  which  compare  with  the  bank  as 
marked  on  Sheet  xv.,  a.i>.  1873,  and  enlarged  plan  Wexford  Harbour,  a.d.  18479 
and  Wexford  Harbour,  a.d.  1873. 


454  Proeeedtptga  of  the  Hoj/al  IrUh  Academy. 

Now,  however,  the  force  of  the  efflux  is  much  less,  and  the  Dogg&r 
bank  has  changed  into  a  long,  narrow  N.E.  and  S.W.  shoal,*  consider- 
ably overlapping  the  mouth  of  the  estuary  and  the  end  of  the  Baven 
ridge.  This  shoal  is  gradually  accumulating,  so  that  now  there  is  a 
long,  narrow  N.E.  and  S.W.  island  formed.  The  change  in  the  efflux 
from  the  Wexford  lagoon  has  not  only  affected  the  Dogger  bank  at  its 
immediate  embouchure,  but  also  the  off  shore  shoals ;  as  when  the 
current  from  Wexford  harbour  was  pushed  northward,  the  Lucifer 
shoal  began  to  be  denuded,  and  is  now  gradually  wasting  away :  the 
outline  of  the  Blackwater  bank  is  also  changing.  The  present  Dogger 
bank  also  forms  a  half -tide  "counter-tide,"  running  to  the  6.W., 
which  strikes  on  the  Rosslare  ridge,  and  is  rapidly  cutting  a  passage 
through  it.  On  account  of  the  present  currents  and  dnftage,  the 
passage  and  bar  of  Wexford  harbour  are  ever  changing ;  this,  how- 
ever, could  be  materially  prevented  by  an  artificial  regulation  of  the 
currents,  and  consequently  of  the  driftage. 

Between  the  North  bay  and  the  Cahore  shingle  beach  there  arc 
high  drift  cliffs,  which  are  weathering  rapidly,  as  high  tides  wash 
their  base ;  some  of  this  drift  is  very  stony,  but  the  stones  out  of  it 
do  not  form  a  shingle  beach  at  the  base  of  the  cliff,  but  are  sucked  out 
seaward  to  low- water  of  neap  tides  (<f,  fig.  5),  along  which  line  they 
are  drifted  northward,  some  of  them  eventually  to  be  cast  up  to 
augment  the  Cahore  shingle  beach.  In  the  neighbourhood  of  Cahoru 
Point  there  is  a  slight  "counter-tide,"  in  connexion  with  the  shoals 
called  the  Bush  bank  and  the  Bam ;  this  forms  a  race  called  the 
"Sluice  of  the  Ram."  This  counter-tide  slightly  affects  Cahore 
shingle  beach,  on  which  account  the  largest  fragments  are  not  found 
at  its  northern  end. 

The  Cahore  shingle  beach  margins  a  ridge  of  ^olian  sand,  and 
when  the  sea  was  at  the  height  of  the  present  Ordnance  twenty-five 
feet  contour  line,  there  was  an  island  at  Cahore  Point  having  a  con- 
siderable sheet  of  water  to  the  S.W.  of  it ;  this  was  subsequently  a  peat 
bog,  when  the  land  was  about  thirty  feet  higher  than  at  present ; 
afterwards  a  lagoon,  separated  from  Uie  sea  by  a  ridge,  and  now  it  is 
all  more  or  less  reclaimed.  At  first,  to  drain  it,  a  canal  was  mado 
through  the  centre  of  the  ridge  on  the  S.W.  of  Cahore  Point.  This, 
however,  was  always  being  filled  by  the  driftage  from  the  south,  and 
now  the  tract  is  drained  by  a  canal  which  empties  itself  into  the  sea 
through  a  culvert  in  a  pier  that  has  been  built  at  Pollduff,  a  little 
N. W.  of  Cahore  Point.  This  canal,  unfortunately,  is  not  effective,  on 
account  of  the  site  of  the  pier ;  opposite  to  the  mouth  of  the  culvert 
is  a  breakwater,  behind  which  the  sand  collects  and  dams  up  the  water ; 
and  between  the  Point  and  the  pier  is  a  bay,  in  which  the  driftage 
collects:  this,  during  N.E.  winds,  which  arc  those  that  most  prevail  at 


♦  Admiralty  Chart,  Sheet  xv.,  1873,  and  enlarged  plan  Wexford  Harbour, 
iUD.  1873. 


KiNAHAK — Tidal  Currents  and  Wind-toaves.  466 

tlie  time  the  canal  ought  to  be  acting,  causes  the  pier  to  be  silted  up  by 
sand  and  gravel.  Here  the  sand  and  gravely  collected  during  months  by 
the  N.E.  winds,  will  be  carried  away  by  one  good  continuous  gale 
during  spring  tides  from  the  S.W.  A  short  gale  would  do  the  work, 
were  it  not  for  the  sand  in  the  bay  between  the  pier  and  the  Point, 
this  having  first  to  be  removed,  as  otherwise  the  tidal  driftage  from 
the  south  will  replace  the  sand  on  the  north  of  the  pier  as  fast  as  it 
is  removed. 

From  Cahore  to  Kilmichael  Point,  the  driftage  seems  to  be  in 
general  even  and  regular,  its  direction  being  to  the  northward.  Be- 
tween these  two  points  is  Courtown,  on  the  Owenavorragh  river, 
where  piers  and  other  works  have  been  constructed,  but  unfortu- 
nately, the  harbour  is  almost  useless,  as  its  embouchure  is  nearly 
always  silted  up.  Here,  also,  is  an  example  of  the  superior  driftage 
power  of  the  tidal  currents  over  the  wind- waves.  Some  years  ago,  a 
storm  swept  away  the  end  of  the  south  pier,  after  which  the  N.E. 
gales  used  to  clear  out  the  bar  in  the  mouth  of  the  harbour,  but  lately 
the  end  of  the  south  pier  was  rebuilt,  since  when  similar  gales  do  not 
clear  the  bar.  The  reason  for  this  is  quite  apparent,  as,  prior  to  the  end 
of  the  south  pier  being  rebuilt,  gales  from  the  N.E.  excavated  out,  not 
only  the  accumulations  forming  the  bar,  but  also  the  accumulations  be- 
tween the  piers  and  the  headland  (Breanoge  Head),  a  little  to  the  south ; 
now,  however,  such  gales  can  only  affect  the  bar,  the  south  bay  being 
protected  from  their  influence ;  consequently,  as  fast  as  the  bar  is  re- 
moved, the  tidal  driftage  replaces  it  with  other  materials.  This  place 
seems  to  be  more  favourably  situated  for  the  construction  of  a  harbour 
than  any  other  on  the  S.E.  coast,  if  the  driftage  was  taken  into  con- 
sideration and  provided  against. 

A  mile  due  east  of  Kilmichael  Point,  is  'Hhe  tail"  of  the  Glass- 
gorman  bank,  and  in  a  nearly  east  and  west  line  between  them  in 
the  '*  race  of  Kilmichael."  This  is  due  to  the  tide  from  the  south  here 
meeting  a  counter-tide  generated  near  Arklow  Head.  Immediately 
north  and  south  of  Kilmichael  promontory,  as  in  many  other  places  on 
this  coast,  there  were  in  years  gone  by  considerable  bays,  which  have 
been  since  filled  up  by  accumulations,  principally  of  JBolian  sand, 
while  of  late  years  these  sand  hills  have  been  considerably  denuded 
at  their  southern  ends.  In  the  bay  to  the  south  of  Kilmichael, 
over  thirty-five  acres  in  area  have  been  carried  away  since  the 
Ordnance  maps  were  made  (1840),  and  in  that  to  the  north  about 
thirty  acres.* 

In  the  tract  to  the  south  of  Kilmichael,  the  encroachments  on  the 
^olian  drift  only  take  place  during  galesfrom  the  S.W.  This  is,  as  might 


*  Thero  aro  no  reliable  records  prior  to  the  Ordnance  Survey,  but  the  old  men 
remember  when  the  land  extended  much  more  seaward  than  is  indicated  by  the 
Ordnance  maps.  In  confirmation  of  their  statements,  they  point  to  the  old  road- 
ways, which  now  lead  to  nearly  perpendicular  cliffs. 


456  Proceedings  of  the  Royal  Irish  Academy. 

be  expected,  the  wind  action  being  combined  with  the  tide,  and  thus 
creating  an  increased  driftage ;  but  in  the  tract  to  the  north,  the  wind- 
waves  act  against  the  driftage  of  the  **  counter-tide ; "  yet  the  princi- 
pal denudation  is  at  the  south  end  of  the  accumulation,  and  what 
apparently  is  more  remarkable,  immediately  to  the  northward,  between 
Clogga  and  Arklow  Head,  there  is  another  similar  accumulation  of 
^olian  sand,  where  the  principal  driftage  is  not  northward  with  the 
wind-waves,  but  southward  with  the  counter-tide.  This  exception  in 
the  bay  between  Clogga  and  Kilmichael  is  the  only  place  on  the 
whole  of  the  coast  line  in  these  charts,  where  the  drifting  power  of  the 
wind- waves  seems  to  exceed,  or  even  equal,  that  of  the  tidal  current ; 
possibly,  however,  this  apparent  anomaly  may  be  due  to  the  tides 
during  springs  running  direct  on  to  the  coast  hereabout,  from  "the 
tail "  of  the  Glassgorman  bank ;  but  in  support  of  such  a  supposition  I 
could  get  no  evidence.  Under  ordinary  circumstances,  the  driftage 
hereabouts  seems  to  be  southward  with  the  "counter-tide,"  as  the 
fragments  of  the  rocks  are  carried  south  along  the  beach.* 

North  of  Arklow  Head,  opposite  the  valley  of  the  Ovoca  river,  there 
was  formerly  a  large  iEolian  sand  accumulation  enclosing  a  lagoon, 
and  from  what  now  remains  it  is  evident  that  formerly  the  drfitago 
from  the  southward  shifted  the  embouchure  of  the  Ovoca  river  some- 
what northward ;  now,  however,  by  piers  and  other  artificial  means, 
an  entrance  has  been  made  and  kept  open  near  the  centre  of  the  sands. 
Here  also,  as  at  Pollduff  and  Courtown,  the  works  have  not  been  effi- 
cient. Formerly,  N.E.  gales  cleared  out  the  bar,  but  of  late  years 
the  south  pier  was  lengthened,  which  has  had  the  same  effect  (and 
for  a  similar  reason)  as  the  rebuilding  of  the  south  pier  at  Courtown, 
previously  mentioned. 

From  Arklow  to  Mizen  Head,  and  from  that  to  Ardmore  Point,  the 
tide  and  driftage  seem  very  regularly  northward.  In  the  different  bays, 
in  all  of  which  there  are  ^olian  sands,  the  tide  cuts  a  little  from  the 
southern  extremities  of  the  banks,  while  more  or  less  is  added  to  the 
north  end ;  except  in  Jack's  Hole,  where  the  bank  has  been  added  to 
considerably  all  along.  Here  it  may  be  mentioned,  that  on  this  coast 
the  outer  margin  of  the  sand  hills  is  now  generally  more  regular  than 
when  the  Ordnance  maps  were  made,  in  general  all  the  jutting  out 
portions  having  been  cut  away,  or  the  hollows  filled  up. 

Between  Ardmore  and  Wicklowf  there  are  various  complications 
on  account  of  the  points  and  shoals  that  generate  **  races"  and  "  coun- 
ter-tides."    Of  these  "  counter-tides"  the  larger  one  begins  near  Five 


*  These  "counter-tides"  eociu  to  have  been  very  little  studied,  and  are  not 
marked  on  the  chart.  Neither  the  coastguards  nor  the  fishermen  seem  to  be  per- 
fectly acquainted  with  them.  They  all  know  the  ordinary  "  set,"  and  allow  that 
this  at  times  changes,  but  the  exact  time  of  the  change,  and  the  cause  of  it,  they 
cannot  tell. 

f  Wicklow  is  situated  immediately  outside  the  north  margin  of  the  area  included 
within  the  limits  of  the  Chart,  Shoot  xv. 


KiNAHAN — Tidal  Currents  and  F  ind-waves.  457 

mile  Point,*  on  the  north  of  Wicklow,  and  flows  southward  to  Bride 
Head,  off  which  there  is  a  considerahle  "race."  This  '*  counter-tide" 
drifts  the  beach  southward,  and  thereby  has  formed  a  shingle  and  gra- 
vel ridge,  which  has  pushed  the  Varhy  southward,  until  its  farSier 
progress  in  that  direction  was  stopped  by  the  hard  rocks  that  form  the 
Wicklow  Head  promontory,  the  pent  up  waters  forming  a  lagoon  and 
marshes.  Here,  at  the  south  end  of  the  ridge,  the  dnftage  seems  to 
be  carried  to  sea;  for,  as  in  other  places  where  a  rock-bound  coast  stops 
the  further  growth  of  a  ridge,  the  embouchure  out  of  the  lagoon  seems 
to  have  a  permanent  bar :  but,  what  here  appears  remarkable,  this  bar 
has  not  changed  during  late  years,  although  half  the  waters  that  used 
to  come  down  the  Vartry  are  now  diverted  to  supply  Dublin. 

These  notes  record  what  has  been  going  on  during  late  years,  but 
it  has  to  be  remembered  that,  during  comparatively  recent  years,  large 
bays  existed,  that  are  now  filled  up  with  JEolian  sand.f  Why  the 
sand  banks  accumulated  in  these  bays  seems  to  be  due  to  a  slight  rise 
in  the  height  of  the  land,  as,  when  the  sand  has  been  removed  by  wind, 
ancient  sea  beaches  are  found  under  them.  If,  therefore,  their  accu- 
mulation was  due  to  a  rise  in  the  land  level,  it  appears  probable  that  in 
those  places  where  the  sand  banks  are  now  being  denuded,  there  must 
be  a  sUght  fall  going  on  in  the  level  of  the  land.  The  difference,  how- 
ever, in  the  levels  is  so  slight  that  changes  in  the  height  of  the  Eise 
and  Pall  of  the  tide  (Pull  and  Change),  possibly,  might  account  for  the 
denudation,  without  the  level  of  the  land  changing. 


'Results. 

The  information  gathered  on  this  portion  of  the  coast  of  Ireland 
goes  to  prove  the  following : — 

First — The  driftage  due  to  the  incoming  tidal  current  is  always, 
during  its  progress,  going  on  in  deep  water,  and  more  or  less  in  shal- 
low water. 

Second. — The  driftage  due  to  wind- waves  only  occurs  during  gales, 
and  even  then  is  only  due  to  the  waves  that  break  on  the  shores. 

Third. — To  prevent  the  tidal  driftege  (arrow  A  Pig.  7),  groins,  or 
piers,  should  be  erected ;  and  if  the  pier  (h)  is  to  form  a  harbour  (/), 
transverse  groins  {e  c^)  should  run  out  from  it,  to  stop  the  back  wash ' 
generated  by  the  pier,  for  otherwise  this  back  wash  would  carry  the 
driftage  seaward,  in  the  direction  of  the  arrow  (d),  to  be  sucked  round 
the  pier  into  the  harboiy  (/). 

Fourth. — As  the  wind- wave  driftage  occurs  during  gales,  and  then 
only  on  the  shore  line,  it  might  be  prevented  from  fillmg  up  a  harbour. 


♦  Admiralty  Chart,  Sheet  xvi. 

t  About  a  mile  S.S.W.  of  Kibnichael  Point,  the  writer  wa«  shown  a  rock  cliff, 
recently  exposed  by  the  denudation  of  the  ^olian  drift,  that,  prior  to  the  accumu- 
lation of  the  latter,  seenu  to  have  heen  quarried  by  man. 

B.I.A.  PROG.,  8SB.  II.,  VOL.  II.,  8CIBNCZ.  3B 


458 


Proceedings  of  the  Boyal  Irish  Academy. 


or  damaging  the  shipping  in  it,  by  placing  a  breakwater  (0,  fig.  7) 
across  the  direction  {arrow  B)  from  which  the  prevailing  storms  come. 


Fio.  7. 


If  such  a  breakwater  were  a  fixed  one,  built  of  stone  or  wood,  it  must 
more  or  less  affect  the  tidal  driftage,  and  probably  would  help  to  fill  up 
the  harbour.  But  if  it  was  floating,  it  ought  to  break  the  wind- waves 
in  deep  water,  thus  destroying  their  drifting  powers,  while  there  would 
be  no  impediment  to  interfere  with  the  tidal  driftage.  The  exact  form 
of  the  pier,  whether  straight,  or  slightly  curved,  as  represented  in  the 
figure,  would  have  to  be  determined  on,  after  experiments  on  the  sets 
of  the  currents,  at  the  place  where  the  pier  was  to  be  built. 


Studdbbt — On  Free  and  Aiiuminoid,  Ammonia,        469 


XLI.  —  An    EsrncATiow  op    the    Fkee    and  Albuminoid  Ammonia. 

TISLDED  BT  THE  STAGNANT  WaTEBS  OF  THE  DtTBLIN  StBEETS, 
AS  COMPABED  WITH  THE  QUANTITIES  OP  THOSE  SuBSTANCES  OB- 
TAINED fbox  theLipfst  Wateb,  apteb  beceitino  the  Sewage. 
By  Lancelot  Studdebt,  LL.D.,  Ex-S.  T.C.D. 

[Read  lOtH  January,  1876.] 

DuBiNG  the  Session  of  1874-5  of  the  Eoyal  College  of  Science, 
StephenVgreen,  several  examinations  were  made  there  of  Dublin  well- 
waters  ;  and  also  some  determinations  like  those  that  follow  for  the  river 
water.  As  a  sequel  to  those  analyses,  the  suggestion  of  the  Professor 
of  Chemistry  in  that  college,  Mr.  Galloway,  induced  me  to  undertake  a 
series  of  estimations  of  the  ammonia  yielded  by  the  surface-water  of 
some  streets  and  squares  in  Dublin,  taking  as  the  standard  of  compa- 
rison the  water  of  the  LifPey,  near  where  the  sewage  is  discharged  into 
the  river. 

The  results  of  my  examination,  conducted  during  November  and 
Decembe  r  last,  in  the  College  of  Science  Laboratory,  are  now  laid 
before  the  Boyal  Lish  Academy. 

Altogether  twenty-nine  of  these  street  waters  were  examined  :  the 
samples  dealt  with  were  collected,  in  my  presence,  at  the  times  and 
places  stated  in  the  Table  appended  to  this  paper  :  the  mud,  also,  left 
from  some  of  these  pools,  was  examined  for  ammonia,  which  reached 
two  parts  in  the  hundred,  calculated  after  allowing  for  moisture  ex- 
pelled at  212^  Fahrenheit.  The  river  water  was  collected  at  inter- 
vals during  the  two  months,  from  four  different  places,  namely,  at 
Eden-quay,  Aston's-quay,  Burgh-quay,  and  Sir  John  Eogerson's-quay, 
four  hours  after  high  water  at  Dublin  bar. 

The  method  employed  for  determining  the  quantity  of  ammonia 
yielded  by  these  waters  and  muds  is  that  devised  by  Messrs.  Wanklyn 
and  Chapman.  This  process  is  almost  universally  allowed  to  be  tiiie 
best  yet  made  known  for  ascertaining  the  character  of  the  nitrogenous 
matter  in  waters ;  its  quantitative  results  are  accurate,  and  they  are 
obtained  with  rapidity.  It  may  be  well  to  state,  for  the  information 
of  any  unacquainted  with  the  Wanklyn  and  Chapman  process,  that 
under  the  term  **  free  ammonia^'' ^  these  chemists  include  ammonia  not 
only  present  ae  suck,  or  in  combination  with  acids,  but  also  the  ammonia 
that,  after  adding  a  saturated  soda  carbonate  solution,  is  evolved  by 
distillation  from  urea,  or  other  easily  decomposable  nitrogenous  organic 
bodies.  The  term^M  ammonia  is  therefore  not  strictly  correct ;  but, 
taking  it  in  this  special  sense,  it  would  be  difficult  to  substitute  any 
other  term  more  convenient,  or  less  open  to  objection. 

The  Table  of  results  gives  the  figures  for  the  Liif ey  standard  at  the 
head  of  the  Hst.  The  quantities  of  the  free  and  the  albuminoid 
ammonia  obtained  from  the  several  street  and  Liffey  waters  are  calcu- 
lated as  grains  in  the  gallon,  and  also  as  milligrammes  in  the  litru 
of  each  water,  respectively,  examined. 

B.  I.  A.  FROC.,  tlR.  II.,  VOL.  II.,  SCIENCE.  3  C 


460  Proceedinga  of  the  Royal  Irish  Academy, 

The  average  of  free  ammonia  from  the  four  samples  of  the  river  Ib 
0  0982,  or  under  iV  of  a  grain  in  the  gallon ;  the  average  of  albuminoid 
ammonia  from  the  same  is  0  0779,  or  under  iV  of  a  grain  in  the  gallon. 

It  may  be  interesting  to  note  that  the  examination  of  the  river 
water  referred  to  as  having  been  made  by  other  workers  in  the  College 
ut*  Science  Laboratory  in  1874,  gave  a  result  equal  to  my  average  in 
1875  :  thus  shewing  a  remarkable  constancy  in  the  state  of  the  llffey. 

It  may  also  be  remarked  in  passing  that  my  average  for  free  am- 
monia is  less,  but  for  albuminoid  ammonia  is  greater,  than  the  average 
Messrs.  Wanklyn  and  Chapman  reported  as  that  of  the  Thames  at 
London-bridge,  in  June,  1867  :  that  river,  the  tide  being  at  two  hours 
flood,  yielding  free  ammonia  =  0' 1232  of  a  grain  per  gallon  ;  and  albu- 
minoid ammonia  =  0*0245  of  a  grain  to  the  gallon. 

The  average  of  free  ammonia  obtained  from  the  29  street  waters 
is  17  grains  to  the  gallon;  that  is,  over  170  times  the  like  average 
from  the  river.  The  average  of  albuminoid  ammonia  from  the  street 
water  is  3  grains  to  the  gallon,  or  88  times  the  Liffey  average. 

It  will  be  seen  by  the  Table,  that  from  three  out  of  the  four  river 
samples,  the  quantity  of  free  ammonia  was  under  that  yielded  by  any 
of  the  street  waters,  except  at  Stephen' s-green,  East  and  South. 

The  maximum  of  free  ammonia  from  the  river  was  at  Burgh-quay, 
and  only  reached  0*175,  or  less  than  i  of  a  grain  to  the  gallon ;  whilst 
the  maximum  of  free  ammonia  from  the  street  waters,  namely,  at 
Moss-street  and  Poolbeg-street,  was  105  grains  to  the  gallon,  that  is 
exactly  600  times  greater  than  the  river  maximum. 

The  least  impure  of  the  29  street  waters  yielded  nearly  three  times 
more  albuminoid  ammonia  than  the  most  impure  sample  of  the  river 
water;  for  instance,  the  surface-water  at  Merrion-square,  South, 
being  the  best  of  the  street  waters,  yielded  0*280  of  a  grain,  against 
that  obtained  from  the  river  at  its  worst,  namely,  0098  of  a  grain,  or 
nearly  3  to  1 . 

But  the  bad  preeminence  of  the  water  in  Moss-street  and  at 
Peler-place  (comer  in  Adelaide-road),  and  in  Lee's-lane,  off  Aston' s- 
quay,  namely,  10  and  10*15  and  11*2  grains  of  albuminoid  ammonia 
from  one  gallon  of  each  water,  respectively,  is  more  than  100  times 
greater  than  the  Liffey  maximum. 

Messrs.  Wanklyn  and  Chapman  conclude  from  a  wide  induction 
of  experiments  that  **  the  disintegrating  animal  refme  in  the  river 
[Thames]  would  be  pretty  fairly  measured  by  ten  times  the  albuminoid 
ammonia  which  it  yields."  In  this  way,  the  average  of  such  refuse 
in  the  Liffey  is  0*779,  or  just  }  of  a  grain  in  the  gallon ;  whilst  the 
average  of  such  refuse  in  the  street  waters  is  29  grains  to  the  gallon. 

That  much  of  this  enormous  amount  of  animal  matter  thus  in  our 
midst  must,  if  not  rapidly  removed,  take  forms  that  will  vaporise, 
seems  all  but  certain,  since  the  conditions  for  spontaneous  decompo- 
sition may  be  said  to  be  always  present :  there  are  the  moisture  and 
heat  required  for  this  chemical  diange,  and  then  there  occutb  at  in- 
tervals the  drying  up  of  these  stagnant  pools. 


Studdbrt — On  Free  and  Albuminoid  Ammonia.        4ST 

My  examination  of  these  street  waters  found,  as  might  be 
epcpectedy  sulphuretted  hydrogen,  with  other  sulphides  and  very  offen- 
siTe  Tolatile  substances. 

What  the  effect  must  be  on  the  people's  health  who  dwell  in  an 
atmosphere  contaminated  by  exhalations  such  as  these,  it  is  not  for 
me  to  determine;  this  paper  simply  records  the  facts  of  the  case, 
leaying  conclusions  to  those  physicians  who  make  such  researches  their 
peculiar  study.  But  without  knowing  the  least  of  the  little  that  is 
Known,  even  to  the  medical  faculty,  about  either  the  chemical  or  the 
Serm^theory  as  to  the  propagation  of  disease,  yet  one  of  the  unlearned, 
like  myself,  having  but  ordinary  sagacity,  might  correctly  conclude 
that  the  continued  presence  of  so  much  dirt  in  the  streets  would  go 
far  to  account  for  the  high  death-rate  (33  to  the  1000,  yearly)  lately 
recorded  for  Dublin ;  a  city  whose  situation,  other  things  being  equal, 
might  mark  it  out  as  one  of  the  healthiest  in  the  Empire.  The 
London  "Times,"  last  week,  reviewing  "  Ireland  at  the  close  of  1876," 
laid  this  to  our  charge — ^that  "  dirt  reigns,  and  slays  its  thousands  in 
Dublin  and  elsewhere." 

Whatever  is  to  be  done  with  our  street  sewage,  whether  it  is  still 
to  defile  the  natural  purity  of  the  river,  or  to  be  applied  to  improve 
the  land,  or  only  to  be  thrown  away,  with  great  cost,  into  the  sea ; 
whatever  be  the  destination  of  this  noxious  mass,  whether  it  is  to  be 
gCK)d,  bad,  or  indifferent,  it  certainly  appears,  from  the  results  now 
laid  before  the  Academy,  that  better  scavenging  and  a  level  surface 
for  the  streets  is  at  once  required. 

The  Professor  of  Hygiene  and  Public  Health  in  University 
College,  London  (Dr.  Corfield),  in  reference  to  this  subject,  in  the 
''Manual  of  PubHc  Health,"  edited  by  Hart,  states  that:— "U  the 
streets,  roads,  and  ways  of  a  town  or  district  are  allowed  to  become 
or  to  remain  so  out  oi  repair  as  to  become  receptacles  for  filth,  or  to 
afford,  by  their  inequalities,  depressions  in  which  foul  water  accumu- 
lates, it  is  in  vain  to  look  for  beneficial  results  from  other  sanitary 
measures." 

Table  of  Ebsults. 


■ 

Dateofcollec- 
tkm  of  water. 

Place  of  collection  of 
water. 

Frsb  Ammonia. 

Albuminoid  Ammonia. 

gaUoiT 

Milligram, 
per  litre. 

Grains  per 
gallon. 

Milligram. 
pcrBtre. 

1876. 
November  11, 

December  16, 
„        17, 

LiFFBT  StAITDABI). 

Eden-quay, 
A8ton*8-qiiay, 
BuTtth-quay, 
SirJ.Rogerson'B-q. 

Total  = 

Averages 

00840 
00812 
01760 
00626 

1-20 
116 
2-60 
0-76 

Total « 

Average  « 

00980 
0*0910 
0-0876 
0-0860 

1-40 
1-80 
1-26 
0-60 

0-8927 

0-8116 

00982 

0-0779 

3  C  2 


462  Proceedingi  of  the  Boyal  Irish  Academy, 

Table  of  Results — continued. 


Fun  Ammokia. 

Albuminoid  Ammonia. 

Date  of  collec- 
tion of  water. 

water. 

Grains  per 
ffallon. 

Milligram. 
perUtre. 

Grains  per 

gallon.     , 

MiUigram. 
perBtre. 

1876,  Not.  1, 

StephenVgr.,  N., 

0126 

1-8 

0-238     , 

3-4 

n 

2, 

Em 

0070 

1-0 

0-420     ' 

60 

ly 

3, 

8., 

0070 

10 

0-378     : 

6-4 

y> 

6, 

»,           ^'1 

0-316 

4-6 

0-490 

70 

n 

16, 

Stephen-tt.,  lower. 

12-600 

1800 

6-800 

800 

}} 

n, 

Cross  Kevin-st., 

2-800 

40-0 

1-400 

20-0 

ft 

18, 

Patrick-stieet, 

4-900 

70-0 

1-760 

62-0 

»» 

19. 

Townsend-street, 
Peter-place,       at 

4-660 

66-0 

4-900 

700 

n 

20, 

comer  on    Ade- 
laide-road,    .    . 

6-600 

80-0 

10160 

1460 

)f 

30. 

Baggot-st.,  lower. 

0-700 

10-0 

0-800 

12-0 

December  1, 

Duke-lane,      .    . 

1190 

170 

1190 

17-0 

n 

1, 

Lemon-street  (late 
littleOrafton-st.), 

}    9100 

130-0 

2030 

290 

)} 

2, 

Leeson-st,  lower, 

1-640 

220 

0-910 

130 

2, 

Leeson-lane,    .    . 

10-600 

1600 

2-380 

340 

f) 

7, 

Creighton-street, . 
Sandwith-stieet, . 

1-640 

22-0 

0-980 

140 

» 

7. 

1-820 

26-0 

1-400 

20-0 

}) 

7, 

Boyne-street, .     . 
Abbey-street,  Mid. 
Lees-lane,  Astons'- 

4-200 

60-0 

2110 

81-0 

1) 

8. 
10, 

10, 

3-780 
1  98-000 

1  70-000 

640 
14000 

1-820 
11-200 

26-0 
160-0 

»» 

Sir  J.  Bogerson's- 

ouay,  ChUt9r,     . 

Moss-street,     .    . 

10000 

7-000 

1000 

)} 

10, 

106000 

16000 

10-000 

146-0 

t) 

10, 

Poolbeg-street,     . 

106-000 

1600-0 

7-000 

100-0 

t« 

H, 

Peterson-lane, 

9-800 

140-0 

0980 

140 

}) 

16. 

Frederick-lane,  8., 

7000 

100-0 

1-820 

26-0 

17, 

New-street,     .    . 

13-600 

160-0 

3600 

600 

20, 

Fitzwil]iam-sq.,W. 

0-490 

70 

0-360 

60 

20, 

Merrion-sq.,  N.,  . 

17-600 

2600 

1-760 

26-0 

20, 

0-360 

60 

0-626 

7-6 

tt 

20, 

Total  = 
Arera^  «  17  grs.  c 

0-420 

6-0 

0-280 

4-0 

492-861 

Total- 
Arerage  > 

83-646 

»f  free  am- 

B  3  grs.  of 

monia  per  galloi 
(surface). 

i    of  .water 

albumii 

Doid    am- 

monia 

per^gallon 

of  wat« 

r  (surface). 

Mud  dried  at  2W  F, 
Percentage. — Free  Ammonia.  Albuminoid  Ammonia. 
Peter-place  comer,       1-2857     +     0-6163  =  2  p.  c. 
Lower  Stephen-street,  0*3780  01001 

Boyne-street,  0*4861  0*3640. 


Ball — 0?i  Lagrange's  Equations.  463 


XLII. —  On  ak  Elbmsntabt  Proof  of  '^  Laosakos's  Equatioits  of 
MonoN  IK  Geitebalized  Co-osdikates/'  By  Robsbt  S.  Ball, 
LL.  D.,  F.  R.  8.,  Andrews'  Professor  of  Astronomy  in  the 
University  of  Dublin,  and  Royal  Astronomer  of  Ireland. 

[Read  24th  January,  1876.] 

TsE  proofs  generally  given  of  these  most  useful  equations  depend 
upon  D'Alembert's  principle.  It  is  possible  that  these  equations 
would  be  more  used,  even  in  elementary  Dynamical  problems,  if 
the  method  of  establishing  them  were  simplified.  I  can  hardly 
believe  that  the  proof  here  given  is  new  ;  but  I  have  read  altogether 
seven  proofs  in  seven  different  books,  and  of  these,  five  depend  upon 
D*Alembert*s  principle,  while  the  two  remaining  ones  have  little 
or  nothing  in  common  with  the  method  I  here  give. 

Let  F  denote  the  potential  energy  of  a  Dynamical  system,  and  T 
the  kinetic  energy.  Let  q  be  one  of  the  n  generalized  co-ordinates 
by  which  the  position  of  the  system  is  specified. 

Suppose  the  system  receive  a  displacement  Sq  :  then  the  particle 
of  mass  m,  of  which  the  co-ordinates  are  x,  y,  2,  receives  a  displace- 
ment, of  which  the  components  are 

dx  dy         dz 

cFq^^^      dq^^^    dq^"^' 

The  forces  acting  on  w»,  at  d%  //,  z,  arc 

d'ir  d^t/  d*z 

"^Te'    ""'dP'    '""W 

Hence  the  quantity  of  work  done,   while   the  displacement  3^   is 
made,  is 

(dx     d^x     dy    d^y     dz     dhi\ 

^'"'^[d^'df^d^'de-'d^'dfr 

the  symbol  2  extending  to  all  the  particles  of  the  system. 

The  potential  energy  of  the  system  is  therefore  diminished  by  this 
amount,  whence 


We  have  also 


dV  ^        Idx^    ^     rfy    fl^     dz^    ^2\ 
d{  '        \dq'  df^  dq'de^  dq'  dPf 


464  Proee«dmg»  qf  the  Bojfol  IritA  Academy. 

whence 


dT 


Suppose  the  other  generalised  co-ordinates  be  r,  9,  Sec.,  then  wa 
have 

dx     dx     dq      dx    dr       dx     d* 

dt'd^'dr^dj^'df^drdr^ 

dx     ,      dx  .     dx  ,     ^ 

whence 

d  ldx\      dx 

dq[dt)'^di 
We  therefore  have 

di'^^Ut  '  dq\dt)'^  dt  '  dq\dt)'^~dt  '  dq\dt  )]' 
(dx     dx     dy    ay     dm    dik\ 

'^'^{dt'd^'^di'di'^dt'dir 

whence  by  differentiating, 

dt\dq)      dq"      dq' 
The  remaining  («  -  i)  equations  are  to  be  similarly  proved. 


Plunkktt — On  the  Ea^ploration  of  the  KnockHinny  Cave.  460 


XLIII. — On  the  Exploeation  of  the  Knockninny  Cave.  By  T. 
Plitnkbtt.  With  an  Account  of  the  Animal  Eemains.  By  Rev. 
Professor  Haughton,  M.  D.,  F.  R.  S.,  and  Professor  Macalister, 
M.D. 

[Road  24tli  January,  1876.] 

Thbough  the  pen  of  Mrs.  Hall,  as  well  as  some  other  writers,  who 
were  less  graphic  in  their  delineations,  Lough  Erne  is  far-famed  for 
its  beautiful  and  varied  scenery,  combining  almost  everything  that  is 
lovely  and  picturesque  in  nature — the  very  sight  of  which  is  cal- 
culated to  produce  the  *'  joy  of  elevated  thoughts,"  and  inspire  feelings 
that  only  a  Wordsworth  could  adequately  pourtray. 

In  an  archoBoJogical  point  of  view,  it  is  also  very  interesting, 
as,  scattered  round  its  shores  and  some  of  its  mimerous  islands,  there 
are  a  number  of  rude  stone  monuments,  of  unknown  antiquity.  There 
are  also  numerous  remains  of  an  early  Christian  people,  who  must 
have  attained  a  high  level  of  culture  and  civilization,  as  the  architec- 
ture of  their  churches  and  monasteries — even  in  their  hoary  ruins — 
testify,  together  with  the  round  tower  of  Devenish  Island,  which 
is  one  of  the  finest  in  Ireland ;  but,  according  to  Mr.  Bourke's  theories, 
enunciated  in  his  late  work  (Aryan  Origin  of  the  Celtic  Race),  the 
round  towers  must  be  removed  from  their  recognised  place  in  the 
architectural  history  of  the  country,  and  pushed  back  into  the  dark 
mysterious  past,  or  pre-Christian  times. 

The  cave,  and  its  interesting  contents,  the  subject  of  this  paper, 
add  a  new  feature  to  the  antiquities  found  in  the  valley  of  Lough 
Erne,  and  probably,  in  some  respects,  it  is  unique  in  Europe.  As  far 
as  I  can  ascertain,  the  large  cinerary  urn  (fig.  7),  which  I  found  in  an 
upper  stratum  of  the  cave-earth,  containing  burnt  human  bones,  is  the 
first  of  this  kind  found  in  any  cave  in  Europe. 

Knockninny,  the  name  of  the  rocky  hill  where  the  cave  occurs, 
rises  abruptly  on  the  southern  shore  of  Upper  Lough  Erne,  ten  miles 
from  Enniskillen,  and  two  from  the  village  of  Derrylin.  Its  elevation 
is  neary  700  feet  above  sea  level;  and,  speaking  in  the  language  of 
geologists,  was  recently  an  island.  It  is  bounded  on  the  north-east 
side  by  the  waters  of  Lough  Erne,  and  south-west  by  a  flat  alluvial 
plain,  including  some  patches  of  bog. 

On  approaching  the  hill  by  the  road  &om  the  west  side,  it  pre- 
sents a  bold  and  majestic  appearance,  calculated  to  inspire  feelings  of 
awe.  Owing  to  these  natural  features,  probably,  the  early  Pagans 
regarded  it  as  a  sacred  spot,  and  chose  it  as  the  last  resting-place  for 
their  departed  chiefs,  and  not  of  one  alone,  but  of  several  tribes,  as  we 
may  infer  from  the  fact  that  three  different  modes  of  sepulture  are 
found  on  its  summit,  including  the  cinerary  urn  found  in  tJie  cave. 

On  three  rocky  hillocks,  at  intervals   along  its   top,  there   are 


466  Proceedings  of  the  Royal  Irish  Academy, 

three  Pagan  cams,  and  one  of  them  the  finest  in  Fermanagh.  By- 
accident,  when  the  owner  of  the  place  was  making  a  deep  ditch  along  the 
south  side  of  this  cam,  he  disentombed  two  ornamented  urns,  contain- 
ing burnt  bones.  On  its  eastem  slopes  there  are  two  "  giants*  graves,*' 
one  of  which  I  assisted  Mr.  Wakeman  to  explore.  It  was  an  oblong 
square,  formed  of  rough  limestone  flags,  set  on  edge,  and  measured 
about  1 7  feet  long,  and  4  feet  broad ;  it  yielded  human  bones,  mingled 
with  those  of  animals.  There  were  traces  of  charcoal  round  the 
margin  of  the  grave.  It  was  Mr.  Wakeman' s  opinion,  from  the  pre- 
sence of  the  charcoal  and  animal  remains,  that  they  had  funeral 
feasts  at  the  time  of  burial. 

The  top  of  the  hill  is  about  half  a  mile  broad  at  its  voidest  diame- 
ter. A  county  road  encircles  its  base,  and  is  united  by  a  short 
junction  to  the  road  leading  from  Enniskillen  to  Derrylin. 

The  hill  commands  one  of  the  most  magnificent  and  comprehen- 
sive views  to  be  obtained  in  the  fifty-two  miles  of  country  through 
which  Lough  Erne  passes.  Standing  on  its  top,  and  looking  towaids 
the  north  on  the  opposite  side  of  the  lake,  there  appears,  sequestered 
in  a  shady  nook  on  the  wooded  island  of  Belleisle,  the  square  tower 
attached  to  the  residence  of  J.  G.  V.  Porter,  Esq.,  and  lately  occupied 
by  the  Earl  of  Rosse ;  and  on  the  same  spot,  during  the  fourteenth 
century,  Charles  Maguire  compiled  one  of  the  best  collections  of  the 
annals  of  Ireland,  which  are  known  as  the  Annals  of  Ulster  (Wake- 
man's  Guide  to  Lough  Eme).  Looking  to  the  west,  about  four  miles 
distant,  the  eye  rests  on  the  palatial  residence  of  the  Earl  of  Ennis- 
killen, situated  at  the  base  of  Benaughlin  mountain.  Eastward,  in  the 
dim  distance,  may  be  recognised  the  last  of  a  group  of  mansions  which 
stud  the  shores  of  Upper  Lough  Eme  in  tins  locality — I  mean  the 
seat  of  the  Earl  of  Erne,  contiguous  to  which  the  old  ivy-dad  Castle 
of  Crom,  which  stood  many  a  hot  siege,  raises  its  roofless  but  vener- 
able walls. 

Mr.  Porter,  whose  residence  I  have  described,  is  owner  of  a  large 
portion  of  Knockninny  hill,  and  has  built  a  neat  hotel  at  its  base 
on  the  shore  of  the  lake.  Were  it  not  for  his  enterprising  and 
generous  spirit,  the  public  would  have  no  means  of  visiting  the 
scenery  and  antiquities  of  Lough  Eme,  as  he,  at  considerable  ex- 
pense and  pecuniary  loss,  keeps  a  neat  steam-boat  on  the  lake  for  the 
accommodation  of  t<)unsts.  But  for  this  gentleman  Knockninny  cave 
would  probably  still  remain  unexplored.  Dunng  the  month  of  June 
last  I  had  been  exploring  some  caves  in  the  mountains  west  of  Ennis- 
killen, when  I  happened  to  meet  Mr.  Porter,  and  had  some  conversa- 
tion with  him  on  cave-hunting.  He  at  once  asked  me  to  make 
a  preliminary  inspection  of  the  *'fox  cave"  at  Knockninny,  and 
ascertain  if  it  was  worth  exploring,  proposing  at  the  same  time  to 
supply  any  labourers  I  might  require.  I  at  once  accepted  his  kind  offer, 
and  on  a  convenient  day  visited  the  cave,  bringing  with  me  two 
labourers  who  were  in  Mr.  Porter's  employment,  working  in  a  quarrv 
at  Knockninny. 


Plunkett — On  the  Exploration  of  the  Knockninny  Cave,  467 

The  cave  penetrates  an  escarpment  in  the  south- west  side  of  the 
liill,  and  has  an  altitude  of  about  330  feet  above  the  adjoining  valley. 
Xjeaving  the  road  in  the  valley  which  surrounds  the  base  of  the  hill,  we 
ascend^  a  steep  acclivity  towards  the  east  entrance  of  the  cave,  which 
opens  into  an  indentation  in  the  face  of  the  rock  (fig.  1 ).    On  reaching 


it  I  made  a  careful  examination  of  the  rock  adjoining  the  entrance, 
and  found  that  through  atmospheric  agencies  several  feet  at  the 
entrance  had  crumbled  away.  Seeing  this,  I  ordered  the  men  to 
commence  digging  on  a  grassy  slope,  fully  six  feet  outside  the  door  of 
the  cave.  After  removing  a  quantity  of  dehrisy  and  blocks  of  stone, 
we  found  charcoal,  some  human  remains,  also  bones  of  animals.  Dig- 
ging a  little  deeper,  the  original  floor  of  the  cave  was  laid  bare— 
I  mean  when  it  extended  nearly  six  feet  further  out.  After  clearing 
away  this  accumulated  stuff  towards  the  entrance,  I  found  ^m  the 
depth  the  cave-earth  presented,  when,  we  had  penetrated  a  little  inside, 
that,   although  the  cave  appeared   small,   yet  when  excavated,   it 


468 


Proceedings  of  the  Royal  Irish  Academy. 


^ 


ni 


r^fe^Fyi^ 


'.-^ym^^bi^W^^fm^ 


■fl'iv  II 

.'I      ^ 
I 

I'" 


;'jtili»  ■' 


I 


Pi.uNKETT— Oil  the  Explm^ation  of  the  Knockninny  Cave,  469 

would  be  a  considerable  size,  as  it  contained  such  a  quantity  of  cave- 
earth.  Having  obtained  a  vertical  section  at  the  mouth  of  the  cave, 
4  feet  deep,  and  finding  the  remains  above  mentioned,  I  came  to 
the  conclusion  that  it  would  repay  the  trouble  of  expldHng,  as  I  con- 
jectured from  what  I  found  that  it  would  yield  interesting  relics. 
Without  further  delay  I  decided  on  making  the  necessary  arrange- 
ments to  have  it  thoroughly  explored. 

It  being  on  the  property  of  Lord  Erne,  this  nobleman,  on  being 
asked,  kindly  gave  permission  to  have  it  examined. 

Having  provided  crowbars,  picks,  and  buckets,  we  set  to  work ; 
and  before  giving  a  detailed  account  of  the  exploration,  I  should  state 
that  the  cave  passes  (fig.  2)  into  the  hill  with  a  gentle  curve  for  a  dis> 
tance  of  35  feet,  when  it  narrows  to  a  width  of  2  feet,  and  4  feet  high. 
Passing  through  this  narrow  door  the  cave  immediately  enlarges  to  a 
width  of  6  feet,  and  10  feet  high ;  then,  taking  a  sudden  bend, 
passes  out  westward  od  a  rocky  shelf  on  the  top  of  a  precipitous 
rock.  The  distance  from  the  east  entrance  to  where  it  passes  out 
in  the  west  is  51  feet,  and  varies  in  height  from  10  to  4  feet. 
These  observations  apply  to  the  cave  when  excavated.  When  we 
had  progressed  with  the  exploration  a  few  feet  inside  the  cave,  on 
examining  the  strata,  I  found  it  was  composed  of  five  distinct  layers. 
The  method  I  adopted  in  removing  the  stuff  was — ^first,  to  remove 
the  top  layer  for  a  distance  of  3  feet  (horizontally),  and  so  on, 
layer  after  layer,  to  the  bottom,  putting  in  a  separate  place  any 
object  of  interest  which  I  found  in  each  or  any  of  the  layers.  I 
examined  each  stratum  separately  as  it  was  carried  out  in  buckets, 
turning  it  over  with  a  trowel  so  carefully  that  the  smallest  object 
could  not  escape  my  notice. 

The  upper  layer  was  entirely  composed  of  small  angular  lime- 
stones, somewhat  larger  than  road  stones,  in  which  there  were  no 
objects  of  any  interest  found.  It  covered  the  whole  surface  of  the 
cave  from  the  east  to  the  west  end,  and  had  an  average  depth  of 
from  1  foot  in  the  east  to  18  inches  in  the  west  end.  I  was  greatly 
puzzled  to  know  how  these  stones  could  be  introduced,  especially 
when  I  found  them  so  uniformly  deposited;  but  when  I  was  ex- 
ploring the  west  end  of  the  cave  I  believe  I  was  able  to  solve  this 
problem,  which  I  shall  explain  presently. 

The  next  layer  was  composed  of  black  mould,  and  had  an  average 
depth  of  16  inches :  it  contained  traces  of  charcoal,  some  human  and 
ammal  bones,  quite  dark  in  colour,  produced  by  the  dark  earth  in 
which  they  were  embedded. 

The  third,  or  next  stratum,  consisted  of  a  peculiar  kind  of  brown 
compact  earth,  containing  some  angular  blocks  of  limestone,  which 
bore  marks  of  fire ;  these  stones  must  have  been  carried  in  by  the 
cave  dwellers,  as  no  stones  fell  from  the  roof  in  this  end  of  the  cave, 
as  it  formed  an  irregular  pointed  arch,  the  surface  presenting  a  smooth 
appearance,  the  result  of  water  at  the  time  it  traversed  the  cave, 
lliere  were  also  found  in  it  a  great  many  fragments  of  rude 
pottery,   which  had  a  dark  smoked  appearance,  which  it  is  evident 


470 


Proceedings  of  the  Royal  Irish  Academy, 


were  portions  of  a  cooking  vessel ;  they  corresponded  exactly  with 
some  fragments  I  have  found  in  crannoges ;  there  were  no  marks  of 
any  kind  on  these  pieces  of  pottery  indicating  ornamentation.  On  the 
same  floor  there  were  human  and  animal  remains  found  scattered  far 
apart ;  and  in  no  instance  during  the  whole  exploration  of  this  end 
of  the  cave  did  I  find  human  remains  huddled  together. 

The  fourth  layer  was  composed  of  yellow  clay  traversed  by  veins 
of  brown  earth,  and  yielded  traces  of  charcoal  all  through,  together 
with  human  and  animal  remains. 

The  next  and  lowest  stratum  rested  on  the  solid  rocky  floor  of  the 
cave,  and  to  my  mind  is  the  most  important  of  the  series,  as  it  bears 
evidence  showing  the  extraordinary  changes  which  the  surrounding 
country  has  undergone  since  its  deposition.  In  depth  it  varied  from  1^  to 
2  ft.,  and  consisted  of  gravel  with  a  covering  of  sandy  clay  of  a  yellow 
colour  about  3  or  4  inches  deep.  I  found  no  human  or  ammal  remains 
in  the  gravel,  but  imbedded  in  the  sandy  clay  on  its  surface  I  picked  up 
two  rude  flint  implements  of  Palaeolithic  type;  one  of  them  (fig.  3)  was 


Fig.  3. 


of  a  jet  black  colour,  the  other  (fig.  4)  a  dusky  brown,  and  measuring 
about  3  inches  each.     I  submitted  the  black  flint  to  the  Rev.  Dr. 


Fig.  4. 

Haughton,  who  pronounced  it  Lydian  stone.  None  of  the  material 
from  which  the  flint  flakes  were  manufactured  is  found  in  Fermanagh. 
I  also  found  in  the  same  bed  of  yellow  clay  human  remains,  including 
several  portions  of  a  skull,  the  hollow  sides  of  which  were  filled  with 
the  material  comprizing  the  layer.  After  I  brought  these  portions  of 
skull  out  of  the  cave  I  picked  out  the  clay,  which  was  firmly  packed 
in  their  hollow  sides,  and  found  it  identical  with  the  stratum  from 
which  they  were  taken.  My  object  in  going  so  minutely  into  detail 
is  to  show  that  these  portions  of  skull  could  not  possibly  have  fallen 
during  the  process  of  exploration  from  a  higher  stratum.     There  were 


Plunkbtt — On  the  Exploration  of  the  Knockninny  Cave.  471 

also  some  animal  remains  mingled  with  charcoal  found  in  the  same 
layer. 

Haying  thoroughly  explored  this  end  of  the  cave  up  to  the  narrow 
part  which  intervenes  between  the  east  and  west  end,  and  finding 
it  very  inconvenient  to  advance  any  further  with  the  excavation  from 
this  side,  I  determined  to  try  the  other  end.  Up  to  this  point  there 
were  35  feet  excavated,  leaving  16  feet  still  unexplored.  I  directed  the 
men  to  pass  round  a  steep  rocky  declivity  to  the  west  entrance,  which 
opens  out  on  a  shelf  on  the  top  of  a  precipitous  rock,  and  was  hid 
from  view  by  briar  and  stunted  blackthorn  bushes — after  the  removal 
of  which  we  found  the  entrance  almost  closed  with  debrh  measuring 
only  li  feet  high,  by  2  feet  broad.  This  end  presented  the  same  de- 
nuded appearance  as  the  other.  The  cave  ran  nearly  parallel  with  the 
escarpment,  and  would  have  been  entirely  obliterated  only  for  the 
hardness  of  the  rock  in  which  it  is,  which  appears  as  a  bulge  on  the 
face  of  the  clifF,  and  is  merely  a  fragment  of  a  much  larger  cavern. 

Finding  that  the  cave  formerly  extended  on  this  side  to  the  very 
edge  of  the  cM,  7  feet  from  the  present  entrance,  I  had  all  the  dehrU  and 
stones  removed  which  covered  this  space,  and  found,  as  I  anticipated, 
the  old  cave  floor.  In  this  earth  and  debris  I  found  traces  of 
charcoal.  After  removing  this  pile,  which  had  accumulated  before 
the  entrance,  and  having  now  exposed  a  good  vertical  section  of  the 
mass  of  earth  which  filled  this  end  of  the  cave,  we  removed  each  layer 
separately,  as  was  done  at  the  other  end ;  the  first  was  composed  of 
small  stones,  being  a  continuation  of  the  same  stratum  from  the  other 
end,  but  6  inches  deeper,  being  18  inches  thick.  Being  anxious  to 
know  how  so  large  a  quantity  of  stones  could  be  conveyed  in  and 
deposited  so  imiformly  over  the  surface,  I  made  a  careful  inspection  of 
the  rocky  surface  round  the  entrance.  In  passing  up  a  steep  rugged 
surface  of  rock  which  ascended  ^m  the  entrance,  I  found  that  owing 
to  atmospheric  agencies  small  stones  became  detached  and  rolled  down 
its  suiface,  falling  over  the  cliff  below,  and  forms  the  greater  portion  of 
the  talus  abutting  its  base.  When  the  cave  extended  to  the  edge  of 
the  cliff  these  stones  could  not  possibly  fall  into  it ;  but  when  it  became 
**  weathered,"  and  the  roof  tumbled  in,  forming  a  pile  before  the  pre- 
sent entrance,  almost  as  high  as  the  roof  of  the  cave,  which  caused  the 
entrance  there  to  be  vertical  for  a  few  feet,  and  had  the  external 
appearance  of  a  ''pot-hole;"  right  above  this  aperture  there  was  a 
shallow  trough  which  ran  up  the  face  of  the  mass  of  rock  from  which 
the  small  stones  were  detached,  causing  a  great  many  of  them  in  their 
course  down  from  the  higher  slopes  to  roll  into  the  mouth  of  the  cave. 
Then  rains  and  melting  snows,  owing  to  this  descending  hollow,  con- 
verged towards  the  entrance,  and  there  being  a  considerable  incline 
from  this  to  the  east  end  of  the  cave,  formed  a  current  of  water  with 
force  enough  to  carry  the  stones  over  the  surface  from  the  west  to  the 
east  end  of  the  cave. 

The  above  facts  lead  me  to  infer  that  the  cave  when  occupied  bj 
man,  and  even  up  till  the  time  the  urn  was  deposited  in  the  top 


472 


Proceedings  of  the  Royal  Irish  Academy. 


stratum,  on  which  these  stones  rested,  that  it  extended  (as  I  haye 
already  said)  to  the  edge  of  the  cliff,  as  none  of  these  small  stones  were 
found  in  any  part  of  the  cave  except  the  surface.  Therefore,  I  conclude 
that  7  feet  of  the  rocky  strata  composing  this  end  of  the  cave  has  worn 
away  since  the  urn  was  deposited,  in  which  were  the  last  human 
remains  introduced  into  the  cave.  The  next  or  second  layer  was  oofin- 
posed  of  dark  unctuous  mould  three  feet  thick.  Duiing  the  course  of 
its  removal  we  did  not  £nd  any  remains  except  charcoal  till  we  had 
penetrated  to  a  distance  of  9  feet  from  the  entrance ;  at  this  point  there 
appeared  a  recess  or  niche  in  the  side  of  the  cave.  One  of  the  men 
working  here  struck  a  large  stone  with  the  pick ;  after  it  was  removed, 
and  clearing  away  the  clay  where  it  rested,  the  large  cinerary  urn  was 
discovered,  and  unfortunately  fractured.     It  {^^,  5)  was  inverted  oa 


a  flag,  and  covered  burnt  human  remains.  The  urn  was  packed  in  the 
recess  in  the  rock  with  dry  mould,  and  protected  on  the  side  next  the 
cave  with  the  large  flag,  which  measured  2  feet  4  inches  long,  and  20 


Plunkett — On  the  Exploration  of  the  Knockninny  Cave.     473 

inches  broad.     There  were  fragments  of  a  much  smaller  vessel  found 
'  this  niche,  which  appeared  to  be  rudely  ornamented  (fig.  6),  but 


Fig.  6. 

no  traces  of  human  remains  were  found  in  connexion  with  it,  although 
I  carefully  examined  the  spot ;  probably  it  was  placed  beside  the  re- 
mains of  the  departed  as  a  food  vessel. 

The  burnt  bones  found  in  the  urn  must  have  been  subjected  to 
powerful  heat,  as  their  contorted  appearance  indicated.  They  repre- 
sented a  male  and  female,  as  may  be  seen  by  the  appended  report. 

There  were  no  other  remains,  or  any  objects  of  interest,  found  in 
this  layer. 

The  next  stratum  was  about  2  feet  deep,  and  consisted  of  pale 
brown  and  rather  compact  earth,  including  some  limestone  blocks, 
which  had  evidently  fallen  from  the  roof,  as  its  appearance  indicated. 
During  the  removal  of  this  layer  there  was  nothing  of  interest  found 
except  small  pieces  of  charcoal,  which  I  observed  under  some  of  the 
stones  as  they  were  being  removed. 

The  last  layer  was  now  uncovered,  which  corresponded  exactly 
with  the  lowest  stratum  at  the  other  end,  being  composed  of  yellow 
sandy  clay  and  gravel ;  nothing  of  any  importance  was  found  in  it 
except  the  remains  of  an  ancient  hearth,  consisting  of  ashes  and  char- 
coal, which  was  partly  covered  with  patches  of  stalagmite.  This  was 
found  at  the  very  lowest  and  most  commodious  part  of  the  cave  bottom, 
being  10  feet  high  when  excavated,  and  5  feet  broad.  A  large 
stone,  about  6  cwt.,  rested  with  its  larger  end  on  the  surface  of  the 
hearth,  the  other  and  smaller  end  leaning  against  the  side  of  the  cave. 
I  measured  all  its  surfaces,  and  found  that  it  had  fallen  from  the  roof, 
as  it  corresponded  in  every  way  with  a  cavity  directly  above  it,  and 
if  it  could  have  been  raised  up  to  the  roof  in  the  position  in  wldch  it 
lay,  it  would  have  fitted  into  the  cavity.  The  reason  I  describe  this 
stone  so  minutely  ip  to  show  that  it  was  not  placed  designedly  there. 


474 


Proceedings  of  the  Royal  Iri^h  Acadetny. 


The  smaller  end  formed  part  of  the  base  on  which  the  flag  whicli 
supported  the  urn  rested ;  I  infer  from  this  that  at  the  time  the  um 
was  deposited  there  was  at  least  6  feet  deep  of  earth  in  this  end  of 
the  cave.  From  the  hearth  to  the  spot  where  the  um  was  found 
there  is  a  vertical  space  measuring  5  feet,  and  from  the  um  to  the 
surface  3  feet,  making  a  total  of  8  feet  of  cave  earth,  includ- 
ing the  small  stones  on  its  surface,  all  of  which  it  is  quite  evident 
accumulated  very  slowly.  A  long  interval  of  time  must  have  elapsed 
since  the  early  dwellers  occupied  the  hearth  till  the  time  the  um  was 
placed  in  the  upper  layer  of  cave  earth. 

Dr.  Joyce  says  (**  Irish  Names  of  Places") :  **  In  early  ages  it  was 
usual  to  bum  the  body  and  place  the  ashes  in  an  um,  which  was 
deposited  in  the  grave.  It  seems  very  extraordinary  [he  continues] 
that  all  memory  of  this  custom  should  be  lost  to  both  history  ana 
tradition,  for  I  am  not  aware  that  there  is  any  mention  of  the  burning 
of  bodies  in  any,  even  the  oldest,  of  our  native  writings." 

According  to  Dr.  Joyce,  the  people  who  practised  this  custom  in  this 
country  must  have  been  very  ancient ;  but  according  to  the  chronology 
of  the  cave,  they  are  comparatively  modem.  In  ancient  Greece  and 
Eome,  burning  the  dead  gained  ascendancy  over  other  modes  of  burial 
as  civilization  advanced ;  and,   strange  to  say,  as  Europe  is  attaining 


K«|,?rftr*^tVi*V 


Fig.  7. 


a  higher  level,  of  culture  and  civilization,  this  sentiment  is  evolved, 

and  appliances  invented  to  carry  out  this  advanced  (.')  mode  of  burial. 

The  large  um  (fig.  7)  was  mdely  but  very  strongly  formed,  and  cdto- 


Plunkbtt^ — On  the  Exploration  of  the  Knochnnny  Cave.     475 

posed  of  coarse  material :  brick,  earth,  and  angular  pebbles  of  small  size 
seemed  to  be  what  it  was  composed  of.  It  stood  14^  inches  high,  15 
in  diameter,  and  3  feet  11  inches  round  the  neck;  the  rim  was  l^ 


inches  broad,  and  bottom  2  inches  thick :  the  latter  was  measui'ed 
after  it  was  fractured. 

It  was  almost  devoid  of  ornamentation,  except  a  few  lines  that 
may  have  been  scratched  across  the  rim  when  the  clay  was  soft. 


The  lines  slanted  upwards,  like  the  fibres  of  a  leaf,  to  right  and 
left,  and  closely  resembled  some  of  the  scratched  lines  on  the  terra 
cotta  wheels  figured  in  Dr.  Schleiman's  book  on  ancient  Troy,  which 
he  regarded  as  symbols  of  the  chariot  of  the  sun. 

Professor  Macalister — who  assisted  the  Rev.  Dr.  Haughton  in 
inspecting  the  human  remains  found  in  Knockninny  cave,  together 
with  a  large  quantity  of  animal  bones  and  some  human  remains, 
which  I  found  in  caves  west  of  Enniskillen — ^was  of  opinion,  from 
the  small  proportion  of  animal  remains  found  at  Knockninny,  compared 
with  what  I  discovered  in  the  Knockmore  caves,  that  the  human 
remains  found  in  Knockninny,  in  the  strata  below  where  the  urn  was 
found,  were  introduced  for  the  purpose  of  sepulture. 

There  was  not  a  single  feature  connected  with  the  strata  or  the 
remains  found  therein  to  indicate  burial.  The  Knockmore  caves  were 
nearly  in  every  respect  different  to  Knockninny.  They  passed  into  the 
rocky  mass  with  a  considerable  dip,  and  when  the  waters  which  tra- 
versed them  became  intermittent,  angular  stones  of  various  sizes 
choked  up  some  of  the  narrower  parts  of  the  caves,  causing  a  quantity 
of  rock  debris  and  gravel  to  accumulate  in  the  cave,  while  the  water 
still  percolated  through ;  and  the  principal  portion  of  all  the  animal 
remains  which  I  found,  including  horse,  wild  boar,  wolf,  deer  and 
dog,  together  with  many  other  species,  were  washed  into  the  caves  ^ 

m.  I.  A.  PBOC,  SIR.  II.,  VOL.  n.,  BOIXNCB.  8  D 


476  Proceedings  of  the  Boyal  Irish  Academy. 

and  while  the  water  percolated  through  the  cave,  the  animal  bones 
were  caught  in  the  rock  debris.  This  I  have  evidence  to  prove  beyond 
doubt,  although  these  caves  at  the  present  time  stand  high  above  the 
level  of  any  current  of  water  in  the  locality, 

Knockmnny  cave  was  quite  different ;  it  was  horizontal,  and  (as  I 
have  said  before)  only  a  fragment  of  a  cave  which  passed  through  a 
bulge  in  the  face  of  the  escarpment  from  east  to  west,  a  distance  of 
only  51  feet,  and  open  at  both  ends:  and  after  the  water  which  origin- 
ally ran  through  it  found  a  lower  level  it  became  dry,  and  no  doubt 
was  sought  as  a  place  of  shelter  and  refuge  by  nomadic  tribes. 

Through  the  whole  strata  of  the  cave  the  remains  were  found 
apart;  evenportions  of  the  same  skull  were  found  in  different  parts  of 
the  cave,  but  always  in  the  same  stratum.  These  facts  would  support 
the  theory  that  cannibals  occupied  the  cave  ^m  time  to  time,  or  dur- 
ing the  course  of  ages  solitary  individuals,  who  sought  it  as  a  shelter 
and  occasionally  died  there.  Their  bodies  becoming  decomposed,  their 
bones  became  scattered  over  the  surface  of  the  floor  by  animals  which 
it  is  quite  evident  inhabited  it ;  and  each  successive  floor  of  the  cave,  as 
it  was  slowly  formed,  furnished  its  own  quota  of  animal  and  human 
remains.  The  presence  of  charcoal  in  each  layer  of  cave  earth  would 
corroborate  the  hypothesis  that  it  has  at  various  intervals  been  used 
as  a  habitation. 

I  might  observe,  before  I  pass  on  to  explain  the  nature  of  the  lower 
stratum  of  the  cave,  that  there  is  hardly  any  branch  of  the  human 
race  but  who  at  one  period  of  their  history  were  cave-dwellers,  from 
the  savages  found  in  various  parts  of  the  world  at  the  present  time 
back  through  a  long  past,  even  before  that  ancient  institution  was 
estabUshed,  the  Chinese  Empire.  **  The  Chinese,"  says  Tylor  ("  Pri- 
mitive Culture  "),  **  can  show  with  all  due  gravity  the  records  of  their 
ancient  dynasties,  and  tell  us  how  in  old  times  their  ancestors  dwelt 
in  caves,  and  ate  raw  flesh  till,  under  such  and  such  rulers,  they  were 
taught  to  build  huts  and  prepare  skins  for  garments." 

Then  if  we  turn  to  the  Homeric  Cyclops : — 

"  Housed  in  the  hills  they  neither  buy  nor  sell. 
No  kindly  offices  demand  or  show, 
Each  in  the  hollow  cave  where  he  doth  dwell 
Gives  law  to  wife  and  children  as  he  thinketh  welL" 

In  a  late  volume  by  H.  H.  Bancroft  on  "  The  Wild  Tribes  of  the 
Pacific  States  of  North  America,"  we  read  that  a  great  many  of  these 
tribes  are  cave-dwellers,  and  "  love  the  inhospitable  mountain  and 
their  miserable  burrowing-places  better  than  all  tiie  comforts  of  civi- 
lization." 

I  need  not  go  into  prehistoric  times,  as  the  caves  found  in  all 
countries  bear  witness  to  the  same  fact.  I  will  now  wind  up  this 
paper  with  some  observations  on  the  lower  stratum  of  the  cave,  in 
<^nnexion  with  the  denudation  of  the  surrounding  country. 


Plunkett — On  the  Exploration  of  the  Knock ninni/  Cave.     477 

This  Btratum  (I  have  already  stated)  is  composed  of  gravel  with  a 
coating  of  yellow  sandy  clay,  both  of  which,  it  is  quite  clear,  were 
carried  in  and  deposited  by  water.  On  a  careful  examination  of  this 
material^  I  was  rather  surprised  to  find  that  a  large  proportion  of  this 
old  silt  and  gravel  was  foreign,  not  only  to  the  formation  which  the  cave 
penetrated,  but  even  to  the  hiQ.  Here  in  a  cave  near  the  top  of  this 
isolated  hill,  I  find  the  debris  of  a  gritty  sandstone,  not  found  in  the 
locality  except  in  a  mountain  ridge  on  the  other  side  of  the  valley 
nearly  a  mile  distant,  the  cave  having  an  elevation  of  330  feet  above 
the  valley  bounding  it  on  the  one  side,  and  349  feet  above  Lough 
Erne,  which  bounded  it  on  the  other.  From  whence  did  it  come  ? 
This  was  the  question  I  had  to  answer.  In  order  to  solve  this  difficult 
problem,  I  commenced  to  investigate  the  physical  phenomena  connected 
with  the  geology  of  the  district,  with  which  I  was  slightly  familiar 
before,  but  now  felt  that  a  closer  inspection  was  necessary  and  impor- 
tant, as  I  had  found  imbedded  in  this  lower  stratum  containing  the 
foreign  matter,  the  two  wrought  flints  and  portions  of  a  human  skull 
described  above. 

I  shall  describe  the  outlines  of  the  country  west  of  Knock- 
ninny,  and  give  a  detailed  account  of  facts  I  discovered,  which  clearly 
«how  the  extraordinary  amount  of  denudation  which  has  taken 
place  in  this  locality. 

Knockmnny  skirts  a  group  of  mountain  ridges  which  lie  on  its 
south-west  side,  and  cover  an  area  of  about  15  square  miles.  This 
area  is  represented  on  Jukes'  map  as  a  patch  of  coal-measures.  The 
slopes  of  one  of  these  mountain-ridges  rise  from  the  other  side  of  tho 
vaUey  adjoining  Knockninny,  and  terminate  at  an  altitade  of  1 100  feet 
above  the  sea  level.  The  valley  intervening  between  the  base  of  this 
mountain  and  Knockninnv  is  about  three-quarters  of  a  mile  broad. 
Cuilca  mountain  raises  its  lofty  crest  further  west,  and  at  a  distance  of 
S  miles  from  Xnockninny,  and  is  the  highest  of  the  group,  and  has  an 
altitude  of  2188  feet  above  the  sea.  Standing  on  its  summit  you  may 
see  a  group  of  hills,  to  which  I  have  referred  above.  The  ridges  or 
hills  (for  they  are  of  various  shapes)  lying  next  Cuilca  approach 
nearest  to  it  in  altitude ;  and  the  hills  forming  the  borders  of  the  group 
have  a  much  lower  altitude,  especially  those  on  the  north-east  side, 
which  pass  from  Cuilca  with  a  gradation  down  to  the  valley  of  Lough 
Erne. 

Cuilca  is  a  ridge  about  2^  mileslong,  and  is  entirely  composed  of  sand- 
etone ;  but  in  the  slopes  below  its  base  the  carboniferous  limestone  crops 
out  and  is  continuous  round  through  the  valleys  and  the  base  of  the 
mountains  immediately  surrounding.  The  hills  also  which  form  the 
outskirts  of  this  area  (already  referred  to)  with  a  similar  altitude  to  the 
valleys  around  Cuilca,  are  entirely  composed  of  limestone,  with  the 
exception  of  a  thin  patch  of  sandstone  along  their  tops.  Cuilca  being 
the  backbone  of  the  district  divides  the  drainage  srjrstem  of  the  country, 
and  from  its  base  there  radiates  in  various  directions  a  series  of  valleys 
with  a  considerable  incline  for  several  miles,  which  broaden  from  one  to 

31)2 


478  Pi'occedingH  of  the  Royal  IvUh  Academy, 

fire  milcB  as  they  extend.  Through  one  of  these  Talleys  the  infant 
Shannon  meanders  southwards,  and  issues  out  of  a  caveni  at  the  base^ 
of  Cuilca  known  as  the  ''Shannon  pot." 

I  have  traversed  all  these  mountains  and  examined  their  strata, 
escarpments,  and  intervening  valleys.  (The  latter  reveal  the  lime- 
stone surface).  On  the  face  of  some  of  these  escarpments  thin  seam» 
of  coal  crop  out,  and  in  the  escarpment  in  the  opposite  side  of 
the  valley  there  are  corresponding  seams,  and  similar  strata  as  found 
on  the  other  side,  and  on  both  sides  horizontal.  Some  of  these  valleys 
have  been  scooped  out  to  a  depth  of  1600  feet.  Notwithstanding  the 
presence  of  these  deep  valleys,  all  the  geological  phenomena  found  in 
the  locality  bear  evidence  in  favour  of  the  hypothesis  that  all  these 
mountain  ridges  which  rest  on  a  portion  of  the  great  limestone 
plain  which  covers  the  centre  of  Ireland,  and  are  principally  com- 
posed of  sandstone,  at  one  period  formed  one  continuous  undulat- 
ing plateau  covering  the  limestone  formation  in  this  part  of  the 
country ;  but  the  greater  portion  of  it  has  been  removed  by  denuding* 
forces,  leaving  these  ridges  behind — ^presenting  now  the  appearance  of 
streaks  and  patches  of  snow,  which  sometimes  remain  on  higher  sum- 
mits after  a  thaw,  when  the  sheet  which  covered  the  country  has 
passed  away. 

The  rain  water  which  courses  down  the  sides  of  these  mountain 
ridges  converges  into  little  rivers  which  traverse  the  surface  until  they 
reach  the  limestone  formation  at  a  lower  level,  when  they  generally 
penetrate  its  strata,  and  form  subterranean  passages  which  often  result 
m  deep  ravines.  I  have  examined  a  great  many  of  these  ''swallow 
holes"  which  form  the  entrance  to  tibese  underground  water  ducts, 
and  found  rounded  sandstones  amongst  the  dehru  in  their  bottoms,  of 
considerable  size,  which  were  transported  hither  by  the  current  from 
higher  levels,  where  the  sandstone  thins  out  on  the  surface  of  the 
limestone.  This  description  of  the  geological  features  of  the  loca- 
lity, confused  as  it  is,  may  help  us  to  understand  more  about  the  denu- 
dation of  the  sandstone  formation,  which  was  continuous  from  this 
locality  over  EInockninny  hill  before  it  became  detached  by  denuding 
forces  ^m  the  main  formation  in  the  locality. 

Standing  on  the  east  shoulder  of  Cuilca  you  observe  a  valley  which 
passes  from  its  base  (to  which  I  have  already  referred)  eastward,  and 
broadens  and  deepens  as  it  extends,  and  passes  at  almost  right  angles 
through  the  mountain  ridge  which  bounds  the  valley  on  the  south- 
west side  of  Knockninny,  then  broadens  into  the  valley  of  Lough  Erne 
and  encompasses  Knockninny  at  its  extremities;  and  supposing  a 
current  of  water  filled  this  valley  from  the  base  of  Cuilca  down  to 
Lough  Erne,  a  distance  of  five  nules,  Knockninny,  which  is  situated 
at  its  lower  end,  would  appear  an  island,  and  before  the  valley  which 
surrounds  it  was  sculptured  out  by  subaerial  agents,  the  waters  which 
passed  down  the  slopes  of  Cuilca  passed  over  the  top  of  Knockninny 
into  Lough  Erne. 

The  evidence  supporting  this  hypothesis  I  have  found  on  the  sur* 


Plunkett — On  the  Exploration  of  the  Kmchiinny  Cave.    479 

face  of  Snockiuimy,  wliich  I  shall  now  adduce.  Along  the  top  of  the 
liill  there  are  several  large  ''swallow  holes"  corresponding  in  every 
feature  almost  with  those  I  have  examined  in  the  valleys  surrounding 
Cuilca,  with  this  exception,  that  no  water  passes  through  them.  I 
went  down  into  these  holes,  and  after  removing  the  rubhish  and  debri* 
•on  the  surface,  I  found  in  every  one  of  them  rounded  sandstones  of 
various  sizes  mingled  with  limestones.  I  also  saw  similar  stones  here 
and  there  in  the  dutches  which  form  the  fences  on  the  hill,  which  were 
gathered  off  the  surrounding  surface.  Kow  the  nearest  sandstone 
strata  in  the  locality  are  in  the  mountain  ridge  rising  in  the  south-west 
side  of  the  valley  adjoining  the  hill,  and  the  inteiTening  valley  is  400 
feet  lower  than  the  top  of  Knockninny,  where  the  "  swallow  holes"  are. 
All  these  phenomena  to  my  mind  clearly  show  that  Knockninny  gradu- 
tdly  rose  like  a  huge  boss  or  outlier,  as  the  surrounding  and  softer  strata 
were  being  worn  away  by  denudation.  I  have  examined  its  slopes,  from 
its  east  and  west^shoulders  to  its  base,  and  found  beds  of  gravel  at  inter- 
vals down  the  whole  way,  which  I  regard  as  the  delris  left  behind 
when  nature's  sculpture  was  forming  the  hill.  One  of  these  beds 
occurs  26  feet  below  the  mouth  of  the  cave,  and  is  exactly  the  same  as 
is  found  in  the  bottom  of  the  cave  underneath  the  sandy  clay.  I  ex- 
amined an  escarpment  in  the  ridge  opposite,  intervening  between  Cuilca 
and  Knockninny.  Through  it  the  valley  passes  on  its  way  from  the 
hase  of  Cuilca  to  the  lake ;  in  the  centre  of  the  valley  Knockninny  rises, 
and  I  found  at  an  elevation  of  about  700  feet  above  the  valley,  gritty 
sandstone,  the  debris  of  which  I  found  in  the  rivulets  which  traversed 
its  surface,  and  it  corresponded  with  what  I  found  in  the  cave,  mingled 
with  limestone  gravel.  All  these  facts  point  to  extraordinary  changes 
of  the  surface  of  the  country  which  surrounds  Knockninny. 

Since  the  water  which  formerly  passed  through  the  cave  retreated 
to  a  lower  level,  leaving  the  floor  diy  and  covered  with  this  deposit, 
the  adjoining  strata  have  been  removed  to  a  depth  of  330  feet  below 
the  entrance  of  the  cave.  A  question  here  suggests  itself — did  man 
inhabit  the  cave  immediately  after  it  became  dry,  or  not  until  the 
surface  of  the  country  had  assumed  its  present  outlines?  The  evidence 
found  in  the  cave  is  in  favour  of  the  former  hypothesis,  as  there  was 
not  a  single  particle  of  cave  earth  associated  with  the  flint  implements 
or  human  remains  found  in  the  lower  stratum.  And  it  is  hardly  pro- 
bable that,  during  the  long  period  which  must  have  elapsed  from  the 
time  the  cave  became  dry,  and  formed  a  refuge  or  dwelling  for  savage 
tribes,  till  the  time  the  valley  assumed  its  present  appearance,  no  cave 
earth  would  be  deposited. 

Suppose  we  assume  that  the  cave  was  not  occupied  until  the  sur- 
rounding surface  of  the  country  presented  its  present  configuration, 
then  we  are  bound  to  believe  that  the  cave  earth  must  have  accumu- 
lated very  slowly,  so  much  so  that  an  inch  would  not  be  formed  while 
330  feet  of  rocky  strata  were  washed  away.  And  if  we  take  Croll 
and  Geikie's  calculations  as  to  the  rate  at  which  valleys  are  scooped 
out  (which  is  extremely  slow),  although  they  state  that  they  have 


480  Proceedings  of  the  Boyal  Irish  Academy » 

ducorered the  ''unexpected  rapidity"  with wbicH  the  snztace  is  wasted 
by  denudation,  this  ''rapidity"  amounts  to  1  foot  in  1500  years. 
Denudation  varies  exceedingly,  and  there  is  evidence  in  this  locality 
that  the  denuding  forces  were  much  more  powerful  formerly  than  at 
present. 

No  matter  from  what  side  we  view  the  evidence  furnished  by  the 
cave  deposits  and  its  environs,  we  must,  I  presume,  be  convinced  that 
the  tribes  whose  relics  I  found  in  the  lower  stratmn  are  of  enormous 
antiquity. 

By  going  into  detail  so  much  I  may  have  extended  this  paper  to  a 
weary  length,  but  I  thought  it  better  to  leave  aU  the  facts  connected 
with  the  exploration,  together  with  a  description  of  the  physical  features 
of  the  surrounding  country,  before  the  Members  of  the  Academy,  and  let 
them  form  their  own  cpnclusions. 

At  the  request  of  the  Rev.  Dr.  Haughton,  I  forwarded  the  large  cine- 
rary urn  to  the  Museum  of  the  Academy,  also  its  contents,  together 
wiUi  the  fragments  of  pottery  found  in  the  cave. 

I  am  deeply  indebted  to  the  Rev.  Dr.  Haughton  and  Professor 
Hacalistcr  for  the  appended  Report  on  the  human  remains  found  in 
the  cave. 


Refobt  on  the  Boxes  found  nr  the  Kirocximnnr  Cave. 

Ut.  JETuman  Remains. 

A. — ^Deepest  Series.     Bones  of  an  adult  man  of  unusually  large  size^ 
including — 

1 .  Right  parietal,  large  fragment. 

2.  Squama  occipitis,  „ 

3.  Right  temporal,  complete. 

4.  Left  parietal,  several  fragments. 

5.  Left  squama  temporis,  fragment. 

6.  Portion  of  frontal,  glabellar  region. 

7.  Lower  lateral  incisor  tooth. 

8.  Lower  left  bicuspid  tooth. 

9.  Upper  left  third  molar  tooth. 

10.  Lower  left  third  molar  tooth. 

11.  Third  rib. 

12.  Piece  of  lower  true  rib. 

13.  Hight  malar. 

14.  Left  ulna,  fragment. 

15.  Right  second  metacarpal  bone. 

16.  Right  ischium,  fragment. 

17.  Left  tibia,  „ 

18.  Right  femur,  ,, 

19.  First  phalanx  of  right  hallux. 


Plunkbtt — On  the  Exploration  of  the  Knockninny  Cave.    481 

B. — Second  Series.    Bone  of  adult,  moderate  size. 

1.  Left  temporal,  nearly  complete,   petrous  and  mastoid  ;   of 
much  smaller  size  than  A  3. 

C. — ^Third  Series.    Bones  of  a  child,  aged  about  10-13. 

1.  Bight  ilium,  crest  and  acetabular  epiphysis  absent. 

2.  Left  ilium,       „  „  „  „ 

3.  Portion  of  squama  occipitis. 

4.  Bight  scapula ;  body,  wanting  all  epiphyses. 

5.  Left  scapula,         t9  u  yy 

6.  Epiphysis  of  tibia. 

7.  Left  maxilla,  with  undeveloped  last  molar  teeth. 

The  jaw  appears  more  advanced  than  the  other  bones,  and  may 
have  belonged  to  a  second  child. 

D. — ^Fourth  Series.    Bemains  of  three  adults. 

a     1.  Lower  £u*st  molar  tooth,  left. 

a    2.  Lower  first  molar  tooth,  right, 

a    3.  Left  ilium,  fragment.' 

a    4.  Left  humerus,  lower  end. 

a     5.  Bight  third  (?)  metatarsal. 

a    6.  Bight  tibia. 

a    7.  Bight  fourth  metatarsal. 

a    8.  Bight  radius,  fragment. 

a    9.  Bight  ulna, 

a  10.  Left  radius, 

a  11.  Left  ulna, 

a  \2.  Bight  scapula, 

a  13.  Left  femur, 


h    1.  Left  humerus,  lower  end. 
h    2.  Eragment  of  right  humerus. 

e    1.  Bight  humerus,  enormously  large. 

These  differ  in  size  from  a  4.  Both  sets,  a  and  h^  are  much 
darker  in  colour  than  Series  A,  B,  and  C ;  0  is  much  larger  than  a  4, 
or  &  1  or  2. 


E. — ^Bones  found  in  the  urn,  burnt. 

a     1.  Left  frontal,  with  remains  of  pez^tent  frontal  suture, 

and  moderate  sinuses.     (Fig.  10.) 
h    2.  Left  frontal,  with  smaller  sinus,  and  much  feebler  external 

angular  process.     (Fig.  11.) 


482  rrocvediiuja  of  the  Royal  Irinh  Academy. 

a    3.  Fragment  of  left  frontal,  agreeing  with  No.  1. 
a    4.  Fragments  of  right  frontal,  three  pieces. 
a    6.  Fragment  of  \di  parietal,  six  pieces. 

6.  Fragments  of  squamosal  right  (?). 

7.  Fragment  of  left  petrous  bone. 

h     8.  Fragment  of  right  petrous  and  mastoid. 

a    9.  Squama  occipitis,  left  side,  two  fragments. 

h  \0.  Bquama  occipitis,  left  and  middle,  does  not  fit  No.  9. 

11.  Left  malar. 

12.  Eight  malar. 

13.  Left  ascending  ramus  of  mandible,  9maU  adult. 

14.  Eight  femur,  four  fragments. 

15.  Left  femur,  fragment  of  condyles. 

16.  Lower  end  of  right  fibula. 

17.  Eight  tibia,  fragment  of  shaft. 

18.  Left  tibia,  back  of  inner  condyle. 

19.  CrcBt  of  ilium,  right. 

20.  Left  femur,  back  of  popliteal  ridge  of. 

21.  Eight  humerus,  upper  end,  two  fragments. 

22.  Left  humerus,  lower  end. 

23.  Eight  radius,  middle  of  shaft,  two  fragments. 

24.  Fragments  of  ribs  and  scales  of  long  bones. 

From  No9.  1,  2-9,  and  10,  it  is  obvious  that  the  remains  of  two 
individuals  were  in  the  urn — one  a  well-marked  male,  the  other 
smaller,  probably  a  female. 


The  individuals  whose  remains  are  found  in  the  cave  are  thus 
at  least  eight — possibly  nine — viz. : — 

A      Large  adult  man. 

B       Moderate  adult  man  (?). 

C       Child  (one,  or  possibly  two). 

Da,   D  ^,  two  moderately  large  adults. 

D  c,   Ycvj  large  adult  man. 

Etf.  Male. 

E  h.  Female  (?). 

It  is  possible,  anatomically,  that  D  e  may  belong  to  A,  and  B  to 
either  D  a,  or  D  ^,  if  the  geological  evidence  does  not  forbid  such 
a  fusion.  The  absence  of  all  trace  of  upper  extremities  in  A  and  B 
would  seem  to  indicate  such  a  relationship.  This  would  reduce  the 
miTiiTmiTn  number  of  individuals  to  seven. 


2nd,  Animal  Bones  found  in  Knochninny  Cwe. 

1.  Ganis  lupus,  very  large  jaws  and  femora,  &c. 

2.  Canis  familiaris. 


Plunkett — On  the  Exploration  of  the  Knockninny  Cave.    483 

3.  Canis  vulpes,  one  jaw,  and  seTcral  teeth. 

4.  Gapra  hircns. 

5.  Ovis  aries  (?). 

6.  Sua  scrofa,  some  large  tusks. 

7.  Bob  taurus,  one  rib  notched. 

8.  Lepns  variabilia. 

9.  Lepns  cnniculus. 

10.  Stnmus  vulgaris,  skull. 


The  smaller  number  of  animal  bones  in  proportion  to  the  human 
(hardly  two  of  the  former  for  each  one  of  the  latter)  is  so  different 
from  the  proportion  found  in  the  Knockmore  caves,  that  it  suggests 
a  different  method  of  the  introduction  of  the  human  remains. 


W.F^VW 


Fig.  10. 


Fig.  11. 


484  Proceedings  of  the  Bayal  Irish  Academy. 


XLIY. — Ov  Pebsoval  Ersors  nr  Astbonoxical  Transit  Obsert^- 
Tiovs.  By  JoHK  L.£.  D&eter,  M.A.,  F.R. A.8.,  ABtronomer  at  the  Earl 
of  EoBse's  Observatory. 

[Bead  Febmary  Uth,  1876.] 

Thx  numerous  observations  wbicb  during  this  century  have  been 
made  at  the  astronomical  observatories,  have  made  astronomers  discover 
a  cause  of  errors  in  the  observations,  which  contributes  to  diminish  the 
accuracy  which  might  otherwise  be  expected  from  our  excellent  in- 
struments. It  is  the  ''  personal  error."  And  this  error  exists  oftener 
in  transit  observations  than  in  any  other,  for  which  reason  it  becomes 
of  great  importance  in  determinations  of  longitude,  and  in  every  com- 
parison of  the  results  of  the  determination  of  different  observers  as  to 
the  meridian  passage  of  a  star. 

While  working  at  the  Copenhagen  Observatory,  my  attention  was, 
two  years  ago,  turned  to  the  study  of  this  special  subject,  by  the 
prize  question  of  the  University,  for  the  answer  to  which  I  received 
the  Gold  Medal.  When  I,  later,  as  astronomer  at  the  Earl  of  Kosse's 
Observatory,  had  been  examining  several  catalogues  of  nebulae,  and 
even  in  these  found  the  influence  of  the  observers'  individuality,  I 
was  induced  to  extend  my  researches  on  the  subject.  Added  to  this,  I 
have  been  encouraged  by  several  men  of  science,  in  whose  opinion  I 
could  not  but  place  the  highest  confidence,  who  thought  it  would  be 
of  some  use  to  astronomers,  if  I  published  at  once  all  the  results  of  my 
studies  of  the  literature,  and  my  examination  of  all  observations, 
which  might  contribute  to  the  explanation  of  the  phenomenon.  In 
the  paper  I  have  the  honour  to  lay  before  the  Eoyal  Irish  Academy, 
will  be  found  many  facts  generally  known,  but  I  have  thought  it 
advisable  to  treat  the  subject  in  its  whole  extension,  in  this  way  giv- 
ing to  astronomers  a  complete  account  of  all  the  results  which  can  be 
derived  at  present,  with  respect  to  personal  equations. 

Transits  are  now-a-days  observed  in  two  difTerent  ways,  by  the  eye- 
and-ear  method,  and  by  means  of  the  chronograph,  of  which  the  former 
method  has  been  used  since  Bradley's  time.  IJsing  this  method,  the 
observer  counts  the  seconds  of  the  clock,  and  compares  the  distance  of 
the  star  from  a  vertical  wire  in  the  field  of  the  telescope,  at  the  last 
second-beat  before  the  transit  over  the  wire,  with  its  distance  at  the 
first  beat  after  the  transit.  In  this  way  the  observer  judges  what 
fraction  of  a  second  has  passed  between  the  first  second  and  the 
transit.*  In  the  chronographic  method,  the  beats  of  the  clock,  by 
means  of  an  electric  current,  make  marks  on  a  strip  of  paper,  which  is 


*  Sometimes,  bnt  rarely,  observers  use  another  method,  directly  estunatuig  the 
interval  between  the  second-beat  and  the  transit  (see,  for  instance,  Biiefwechsel 
swischen  Gauss  und  Schumacher,  i.,  p.  368). 


Dreyer — Ow  Astronomical  Transit  Observations.       485 

folded  round  a  slowly  revolying  cylinder,  while  the  ohserver  himself, 
in  the  moment  he  sees  the  star  bisected  by  the  wire,  establishes  (or  in 
some  apparatuses,  interrupts)  a  current  with  a  key,  and  in  this  way 
makes  a  mark  on  the  paper,  between  two  second-marks.  He  can  then, 
afterwards,  measure  tiie  distance  between  these  marks,  and  determine 
the  fraction  of  the  second  with  great  exactitude.  In  both  methods  of 
observing,  it  has  been  found  that  there  exists  a  difference  between  th& 
moments  of  culmination  of  a  star,  as  found  by  dijQferent  observers, 
using  the  same  instrument. 

It  is  to  Bessel  that  we  owe  the  discovery  of  this  personal  differ- 
ence. He  was  not,  however,  the  first  who  remarked  a  different 
estimation  of  transits,  but  his  researches  on  this  subject  were 
occasioned  by  his  finding  in  the  Greenwich  observations  from  1795, 
that  one  of  Maskelyne's  assistants,  Mr.  Einnebrook,  had  got  into 
the  habit  of  observing  transits  over  the  wires  of  the  transit  instru- 
ment 0''d  to  0*'8  later  than  Maskelyne  himself.  In  1794  and  the 
beginning  of  1795,  the  observations  of  the  two  astronomers  had  agreed; 
but  in  August,  1795,  Kinnebrook  began  to  observe  half  a  second  later^. 
which  difference,  in  1796,  rose  to  0"-8.  As  it  was  Maskelyne' s  opinion 
that  his  assistant  did  not  use  the  above  mentioned  way  of  observing 
by  eye  and  ear,  but  some  other  irregular  method  of  his  own,  he  dis- 
missed this,  in  other  respects,  skilful  man.  The  matter  was  looked 
upon  in  this  way  by  everybody;  no  one  thought  that  there  had  been 
found  a  physiological  phenomenon,  which  was  perfectly  independent 
of  the  observer's  will.* 

Bessel  examined  the  matter  again,  and  showed  by  his  excellent 
investigations,  which  in  1823  were  published  in  the  eighth  section  of 
the  Konigsberg  Observations,  that  most  observers  have  a  different  way 
of  estimating  transits.  He  studied  the  equations  between  himself, 
Walbeck,  and  Argelander,  and  communicated  the  results  f »  extensOf 
together  with  researches  on  the  variations  of  the  equations  from  time 
to  time,  the  influence  of  the  magnifying  power,  and  other  circum- 
stances. With  his  usual  acuteness,  he  gives,  besides,  several  hints 
respecting  the  origin  of  the  phenomenon.  The  remarkable  result  of 
Bessel' 8  investigations  was,  that  he  himself  observed  about  a  whole 
second  earlier  than  the  two  other  astronomers.     He  found : — 

In  1 820,    Bessel  -  Walbeck      =  -  1-04. 
In  1823,     Bessel-  Argelander  «  -  l-22.t 


*  Compare   the   history  of  the   GhreenwicH  Obseryatory  in  vol.  xi.  of  Linde- 
nau's  and  Bohnenberger's  '^Zeitschrift  fur  Astronomie  "  (1816). 

ft* 

t  Everywhere  in  this  paper  a  difference  A-Bsi—  i***^^  underBtood  in 


ft*  (  later  ) 
this  way,  that  A  observes  —  j  earlier }  *^""*  ^- 


486  Proceedings  of  the  Royal  IrUh  Aeadeniy. 

In  the  different  equations  which,  in  the  conne  of  jean,  were  found 
between  Beeael  and  W.  StruTe,  there  waa  a  r^^olar  variation: 


1814-8. 

B.- 8.  =-0^04. 

1820-9. 

-  0-68. 

1821-1. 

-  0-80. 

1823-5. 

-  102. 

1834-5. 

-  0-77.» 

The  two  comparisons  from  1821  and  1823  are  indirect,  derived 
from  the  differences,  Struye-Walbeck  and  StruTe-  Argelander,  found 
in  Dorpat  by  direct  comparison.  The  variation  is  very  striking,  and 
this  circumstance,  as  well  as  the  considerable  amount  of  the  personal 
equations,  whose  reality  now  was  beyond  doubt,  showed  the  necessity 
of  examining  this  remarkable  source  of  error  in  all  its  details.  It  is, 
however,  very  seldom  that  personal  differences  are  as  lai^  as  between 
Maskelyne  and  Einnebrook,  or  between  Bessel  and  his  asmstants.  The 
accordance  between  the  different  equations  found  in  Konigsberg, 
with  respect  to  quantity  and  sign,  mi^es  it  most  probable  that  Bessel 
observed  about  a  second  earlier  than  most  astronomers  do ;  and  he 
would  probably  have  agreed  tolerably  well  with  Maskelyne,  as  the 
difference  B.  -  Kinnebrook,  in  the  opposite  case,  would  have  amounted 
to  nearly  2*. 

As  soon  as  the  existence  of  the  personal  equations  had  been 
acknowledged  in  the  scientific  world,  other  astronomers  began  to  make 
researches  in  this  direction.  First  of  all  observatories,  that  in  Altona, 
directed  by  Schumacher,  imitated  those  in  Konigsberg  and  Dorpat, 
and  the  following  remarkable  differences  were  found  there  in  1833 : — 

Nehus  -  Wolfers    =  +  0"-73. 
Petersen  -  Madler  =  +  0*-52.t 

These  observations  were  made  during  a  determination  of  longitude 
by  transport  of  chronometers,  and  since  that  time  very  few  determi- 
nations of  longitude  have  been  undertaken,  without  the  observers  hav- 
ing compared  their  method  of  observing,  as  the  whole  amount  of  the 
personal  equations  otherwise  would  mcike  a  part  of  the  result.  The 
investigations  of  personality  in  observing  transits,  which  have  been 
made  on  the  occasion  of  determinations  of  longitudes,  are  very  impor- 
tant, and  have  produced  many  of  the  most  reliable  results  we  have 
derived  on  this  special  subject.  Besides,  the  plan  for  the  observations 
adopted  in  several  observatories  has  rendered  constant  determinations 
of  the  personal  faults  of  the  observers  necessary ;  and  this  has  espe- 
cially been  the  case  in  Greenwich,  where  all  the  instruments  are 
used  alternately  by  several  observers.  From  the  year  1838,  the 
volumes  of  the  Greenwich  Observations  contain  interesting  discussions 
on  the  equations  between  the  different  observers,  which  we  shall  often 
have  occasion  to  quote  in  the  following  pages. 

*  Kiinigsberger  Beobachtungcn,  viii.,  pp.  6,  6 ;  ibid.  xx.  p.  31. 
t  Astronomische  Nachrichtcn,  xiii.,  No.  3C8  ;  xlix.,  No.  1164. 


Dreyek — On  Astronomical  Transit  Obseiratioas.        487 


Before  entering  on  the  examination  of  the  different  results  which 
can  be  extracted  from  modem  researches,  we*  shall  shortly  consider  the 
methods  bj  which  the  personal  difference  between  two  observers,  and 
the  absolute  personal  error  of  a  single  observer,  may  be  found. 

The  most  convenient,  as  well  as  the  simplest  way,  to  find  the 
equation  between  two  persons  is  to  let  the  one  observe  the  transits  of 
stars  over  the  one  half  of  the  wires  in  the  telescope,  and  the  other  person 
observe  the  transits  over  the  remaining  wires.  The  single  transits, 
reduced  to  the  middle  wire,  give  immediately  the  equation.  By 
changing  the  half  of  the  system  of  wires  observed  by  each  person,  the 
influence  of  faults  in  the  distances  of  the  wires  is  eliminated.  A 
change  of  this  method  is  the  use  of  a  binocular  eye-piece,  which,  by  a 
prism,  divides  the  rays  coming  from  the  object-glass  into  two  parts, 
so  that  two  observers  at  the  same  time  may  observe  the  transit  of  a 
star  across  all  the  wires.  This  method  has  for  some  time  been  used  in 
Greenwich,  but  it  causes  often  a  change  in  the  personal  error  to  arise 
from  the  position  of  the  observer,  east  or  west ;  therefore,  it  cannot  be 
recommended.*  It  is  also  in  another  way  possible  to  use  all  the  wires, 
by  letting  the  two  persons  observe  the  projected  image  of  the  sun  on 
a  piece  of  white  paper,  f  But  as  the  observation  of  the  luminous  edge 
of  the  sun  is  very  different  from  that  of  a  star,  a  personal  difference 
in  the  former  need  not  be  identical  with  that  in  the  latter,  so  that  a 
control  by  star-observations,  at  all  events,  is  necessary. 

Besides  these  methods— of  which  the  first  one  is  the  simplest  and 
the  one  most  commonly  used — several  other  methods  of  finding  per- 
sonal differences  may  be  used.  When  Bessel,  for  instance,  compared 
himself  with  Walbeck,  each  of  them  observed  five  stars  a  day,  and 
every  second  day  the  same.  By  comparing  the  observations  made  on 
two  consecutive  days,  two  values  of  the  clock-rate  were  obtained,  the 
difference  of  which  was  equal  to  the  double  personal  equation.^  The 
equation  B.  -  Argelander  was,  at  the  same  time,  found  in  another 
manner.  Bessel  had,  in  1821,  six  times  observed  seven  stars  (used 
by  Bradley  and  Maskelyne  for  determining  the  collimation  error  of 
the  Greenwich  quadrant) ;  Argelander  observed  twice  the  same  stars 
in  1823,  while  Bessel  found  the  clock-error.  A.  found  now  the  right 
ascensions  to  be  larger  than  B.  had  done :  the  equation  B.  ~  A.  was, 
therefore,  on  an  average  =  -  1**22.  A  similar  method  is  used  in 
Greenwich,  where  the  different  observers  at  the  transit  instrument, 
from  a  series  of  stars,  determine  the  clock-error  separately,  and  reduce 

*  We  shall  afterwards  come  back  to  this  peculiar  case. 

t  About  this  method  see  Washington  Observations,  i.  (for  1846),  p.  49  ; 
Monthly  Not.,  R.  A.  S.,  xiz.,  p.  338;  Monatsberichte  der  ^rliner  Academie, 
1858,  p.  615.    We  shall  also  later  come  back  to  the  solar  ohserrations. 

X  Adnigsberger  Beob.,  riii.,  p.  4.  ^  B.  compared  himself  in  1832  with  Busch 
and  Argelander  in  the  same  way. — Ibid,  xviii.,  p.  1. 


488  Proceedings  of  the  Royal  IrUh  Academy, 

their  results  by  means  of  the  clock-rate  (found  independently  of  per- 
sonal errors)  to  a  common  epoch  (0^  Sid.  time).  The  differences  be- 
tween the  resulting  clock-errors  for  this  epoch  are  then  equal  to  the 
equations  between  the  observers  (with  reverse  sign,  according  to  the 
mode  of  designation  chosen  in  this  paper). 

During  determinations  of  longitude,  the  personal  equation  between 
the  observers  has  often  been  eliminatedi  bj  letting  them  exchange 
their  stations,  and  begin  observing  again.  The  mean  of  the  two  result- 
ing values  for  the  difference  of  longitude  is  then  the  exact  value,  and 
hsdf  their  difference  is  equal  to  the  personal  equation.  This  method 
supposes  the  personal  error  of  both  observers  to  be  constant  during  the 
whole  operation,  but  as  this  is  not  always  the  real  case,  it  is  the  safest 
to  determine  the  equation  in  one  of  the  usual  manners,  best  by  letting 
the  observers  compare  themselves  with  both  instruments  used  at 
the  two  stations.  Sometimes  the  equation  has  also  been  found  by 
letting  the  two  astronomers  observe  simultaneously  at  the  same  place, 
each  using  his  own  instrument ;  but  as  the  uncertainty  in  the  deter- 
mination of  the  instrumental  errors  gets  a  considerable  influence  on 
the  result,  this  method  ought  never  to  be  used. 

But  the  comparison  between  the  habits  of  two  observers  does  not 
give  us  any  information  about  the  absolute  error  of  each  of  them, 
which  it,  of  course,  is  of  far  greater  interest  to  study ;  and  it  has, 
therefore,  during  the  last  twenty  years,  been  attempted  by  several 
astronomers  to  construct  an  apparatus  by  which  the  personal  error  of 
an  observer  could  be  foimd.  As  we  shall  often,  in  the  following  pages, 
quote  results  obtained  by  such  apparatuses,  it  will  not  be  superfluous  to 
give  a  short  description  of  them,  only  entering  a  little  into  details 
respecting  those  wiUi  which  important  and  trustworthy  results  have 
been  obtained.* 

Hartmann  has  described  an  apparatus  in  Gmncrt's  "Archiv  fur 
Ifathematik,''  XXXI.,  1858  (also  in  the  Astron.  Nachrichten,  LXY.), 
which  only  allows  observations  by  eye  and  ear.  A  centrifugal  pendu-  ' 
lam  turns  in  one  second  an  axis  on  which  a  small  disc,  cut  like  an 
Archimedes-spiral,  is  flxed.  At  a  certain  phase  of  the  rotation,  an 
arm,  which  slides  on  the  spiral,  falls  down  and  produces  audible 
second-beats,  while  it,  in  the  same  moment,  sets  an  escApement  free, 
and  causes  a  system  of  wheels,  which  before  were  at  rest,  to  begin  to 
move,  and  after  having  moved  a  certain  part  of  a  rotation — ^which, 
when  the  instrument  is  stopped,  may  be  conveniently  measured — 
causes  an  artificial  star  to  pass  behind  the  wire  in  a  small  telescope. 
While  this  goes  on,  the  observer  estimates  the  moment  between  two 
eonsecutive  second-beats,  in  which  the  star  (a  steel  pearl,  on  the  cir- 
cumference of  a  wheel,  illuminated  sideways)  is  bisected  by  the  wire. 

*  PrazmowBki  in  Warsaw  seems  to  have  been  the  first  one  who  has  invented 
such  an  instroment,  which  was  very  much  on  the  same  principle  as  the  modem 
**  Time-collimatorB."  As  far  as  we  know,  no  researches  made  with  it  have  been 
pubUshed-'Cosmos,  T.  lY.  (1854),  p.  445. 


Db:by£R — On  Aatranomical  jTransit  ObseiTations.       489 

A  comparison  between  tliis  estimated  moment  and  the  true  distance  of 
the  transit  from  the  preceding  second-beat  gives  then  the  personal 
error.  This  instrument  has  only  been  used  a  little  by  the  inventor 
himself,  and  it  is  too  complicated. 

Simpler,  and  therefore  depending  less  on  the  exact  manufacture  of 
all  the  details,  is  the  instrument  used  by  MM.  Plantamour  andHirsch, 
at  the  determinations  of  longitude  in  Switzerland.*  Like  the  in- 
struments of  C.  Wolf  and  Eaiser,  it  makes  use  of  electricity ;  but  in 
another  way,  in  conjunction  with  the  **  chronoscope  "  for  measuring 
▼ery  small  intervals  of  time.  This  chronoscope  is  a  fme  clockwork 
with  two  hands,  which  turn  once,  respectively,  in  0"*1  and  in  10" ;  as 
the  dials  are  divided  into  100  parts  each,  the  one  can  show  0*'001,  the 
other  one,  0*'l.  The  axis  of  l^e  former  hand — which  moves  the  axis 
of  the  latter  by  a  toothed  wheel — can  be  pushed  backwards  and  for- 
wards, by  the  establishing  and  interrupting  of  an  electric  current.  In 
the  former  case,  a  cog-wheel  on  the  axis  is  pressed  against  another 
wheel,  which  is  moved  by  the  clock  and  has  100  teeth,  so  that  the 
two  wheels  will  move  together  after  less  than  0"'001.  When  the  cur- 
rent is  closed  again,  the  axis  goes  forward  and  the  wheels  separate ; 
accordingly,  the  two  hands  are  stopped.  The  passage  of  a  luminous 
point  behind  a  wire  suspends  the  current,  while  the  observer  himself, 
in  the  moment  he  remarks  the  transit,  closes  it  again.  The  hands  of 
the  chronoscope  will,  therefore,  indicate  the  personal  error  of  the  ob- 
server, but,  of  course,  only  if  it  is  negative ;  as  the  hands  in  the  oppo- 
site case  (when  the  observer  closes  the  current  before  it  has  been 
opened)  are  not  moved  at  all,  so  that  it  can  only  be  seen  that  the  ob- 
server has  anticipated  the  transit,  but  not  how  much.f  The  artificial 
star  is  produced  by  a  board,  movable  by  a  pendulum,  with  a  small  hole 
in  it,  through  which  the  light  of  a  gas-flame  shines.  Once  during 
each  oscillation,  in  the  moment  it  passes  the  vertical  line,  the  pen- 
dulum interrupts  a  metallic  contact,  and  suspends  the  electric  current, 
thereby  letting  the  hands  of  the  chronoscope  join  in  the  motion  of  the 
clockwork,  until  the  observer,  with  a  key,  closes  the  current  again, 
and  stops  the  hands.  The  pendulum,  board,  and  gas-flame  were 
placed  in  the  meridian-mark-room  of  the  Observatory  in  Neufchatel. 
An  assistant  has  to  move  the  pendulum  towards  the  east ;  the  ob- 
server lets  it  pass  the  vertical  Hne  towards  the  west,  and  presses  the 
key  when  he  sees  the  star  go  back  again  and  (when  the  pendulum 
again  is  vertical)  pass  behind  the  movable  wire  in  the  transit  instru- 
ment, which  he,  before  the  beginning  of  the  observation,  has  made 
bisect  the  star.    The  metallic  contact  can  be  regulated  by  a  micro- 


*  Determination  T^^graphique  de  la  Difference  de  Longitude  entre  les  Observa- 
tdrea  de  Geneve  et  de  NeufchAtel.     Par  £.  Plantamour  et  A.  Hirsch,  Geneve,  1864. 

t  TluB  case  happened  several  times  during  Plantamour's  observations.  Before 
calculating  the  probable  value  for  the  personal  enor,^  he,  therefore,  left  out  an 
-equal  number  d  the  largest  negative  errors. 


490  Proceedmg$  of  the  Royal  IrUh  Academy. 

meter-screw,  so  that  it  is  interrnptcd  exactly  in  the  moment  when  the 
pendulum  is  vertical,  and  the  star  in  reality  behind  the  wire. 

The  simple  construction  of  this  instrument  guarantees  the  non* 
existence  of  constant  errors  in  the  results  obtain^  by  it.*  But  it  ia 
a  fault  in  it,  that  a  very  considerable  time  is  necessary  for  taking  any- 
great  number  of  observations,  as  it  has  to  be  stopped,  read  off,  and 
set  going  again  after  every  single  wire-transit. 

A  more  suitable  apparatus  was  invented  by  M.  C.  Wolf,  of  the 
Paris  Observatory,  who  has  described  it,  as  well  as  a  great  number  of 
observations  and  special  researches  on  the  personal  errors  and  their 
origin,  in  the   "Annales  de  TObservatoire  de  Paris,"  M6moire8,  T. 
Ylll.f     The  artificial  star  is  produced  by  a  small  opening  in  a  board 
(illuminated  from  behind),  whose  image,  by  a  system  of  lenses,  is 
thrown  on  the  plane  of  five  wires  in  a  small  telescope.     The  board  is 
at  one  end  of  an  arm,  which  by  a  clockwork  can  be  made  turn  round 
its  centre.     In  this  centre  of  the  rotation  is  a  lens  of  very  short  focal 
length ;  the  image  of  the  star  produced  by  this  lens  is  seen  through 
another  lens  placed  before  the  object-glass  of  the  telescope.     The 
image  of  the  star,  seen  by  the  observer  in  the  plane  of  the  wires,  is  in 
this  way  made  to  move  very  slowly,  so  that  the  board  moves  16  centi- 
meters, while  the  image  of  the  star  only  goes  from  the  first  to  the 
fifth  wire  or  12  millimetres.     The  transits  are  observed  by  eye  and 
ear,  wliile  the  small  "  carriage  "  at  the  end  of  the  arm,  underneath 
the  board,  is  furnished  with  a  contact  apparatus  which  automatically 
registers  the  transits  on  a  strip  of  paper  on  which,  also,  the  second- 
beats  of  the  clock  are  marked.     This  apparatus  consists  of  a  steel 
spring  (fixed  on  the  carriage)  with  a  very  small  ball  or  knot  at  the 
end,  which  is  dragged  along  the  surface  of  a  wooden  board,  in  which, 
at  equal  distances,  five  thin  copper  strips  are  inlaid.     The  latter  must, 
before  the  beginning  of  the  observations,  be  adjusted  by  fine  mi- 
crometer screws,  so  that  the  star  will  be  behind  a  wire  in  the  tele- 
scope when  the  contact  of  the  small  ball  with  any  of  the  copper  strips 
closes  an  electric  current,  or,  during  a  retrograde  motion  of  the  st^, 
opens  it.     In  either  case  the  absolute  moment  of  the  transit  wiU, 
therefore,  be  registered  on  the  same  paper  on  which  (by  another  cur- 
rent) the  seconds  are  marked,  so  that  a  comparison  of  the  marks  on 
this  paper  with  the  moments  of  transits  estimated  by  the  observer, 
gives  the  value  of  the  personal  error. 

The  observation  is  made  in  the  following  way : — ^The  apparatus  is 
adjusted,  and  the  observer  sets  the  clockwork  going.  The  contact 
apparatus  and  the  star  will,  however,  stand  still  till  a  small  weight  is 
put  on  a  plate.  This  causes  the  transit  to  take  place.  When  it  is 
over,  the  weight  is  put  on  another  plate,  and  the  star  will  now  go  back 

*  The  very  important  researches  for  wkich  this  apparatus  has  been  used  are, 
however,  independent  of  constant  errors,  as  we  shall  see  further  on. 

f  Recherches  sur  T  Equation  personelle  dans  les  ohservationB  de  passage.  Par- 
M.  C.  Wolf. 


Drbyer — On  Astronomical  Tramit  Observations.        491 

again,  and  pass  the  wires  a  second  time,  this  time  registering  its  tran- 
sits by  the  interruption  of  the  current.  By  placing  a  prism  before  the 
eye-piece  during  this  second  transit,  the  motion  of  the  star  will,  to  the 
observer,  seem  to  take  place  in  the  same  direction  as  during  the  first 
one.  By  this  arrangement  of  the  observations,  small  imperfections  in 
the  contact  apparatus  (which  would  establish  or  interrupt  the  current 
a  little  before  or  after  the  right  moment)  will  have  no  influence  at  all 
on  the  mean  of  two  consecutive  transits,  and  the  bending  of  the 
spring  will  only  cause  an  imperceptible  fault  in  the  same.  Wolf's 
determinations  of  his  personal  error  were  always  founded  on  40  tran- 
sits, 20  in  each  direction,  and  as  the  instrument  was  very  carefully 
treated,  and  all  sources  of  faults  examined,  lus  results  deserve  the 
highest  confidence. 

The  instruments  we  hitherto  have  mentioned  have  not  been  gene- 
jnJly  used  by  astronomers,  but  only  by  their  inventors  and  a  few  other 
persons.  This  is  not  the  case  with  the  different  instruments  successively 
constructed  by  the  late  Professor  Kaiser,  in  Leyden,  which  are  well 
known  in  the  scientific  world,  especially  the  latest  constructed,  which 
lias  often  been  used  in  determinations  of  longitude  on  the  Continent,  as 
well  as  in  Pulkowa,  and  which  is  generally  termed  a  time-collimator. 
Xaiser  has  in  the  course  of  years  constructed  three  apparatus.  As 
early  as  in  1851,  this  eminent  astronomer  proposed  to  apply  the  prin- 
ciple of  the  nonius  to  determinations  of  time,  and  promised  later  to 
describe  an  instrument  based  on  this  principle,  and  suitable  for  finding 
absolute  personal  errors.*  This  promise  he  carried  into  effect  in  1863 
by  publishing  a  paper  which,  besides  the  description  of  the  apparatus, 
contains  a  great  many  observations  taken  with  it.f  The  arm  wliich 
carried  the  artificial  star  interrupted  a  current  in  the  moment  of  the 
transit,  which  caused  an  electro-magnet  to  let  its  armature  fall,  whereby 
a  pendulum,  which  hitherto  had  been  kept  in  its  greatest  elongation 
from  the  vertical  position,  was  set  going.  By  the  coincidences  of  tliis 
pendulum  with  the  clock  used  for  &e  observation,  the  true  moment  of 
the  transit  could  be  determined  with  great  accuracy.  ^Numerous 
experiments  were  made  with  this  instrument  by  the  astronomers  in 
Leyden,  and  Eaiser  introduced  now  the  custom  to  let  astronomical 
students  practise  with  observations  of  artificial  stars. 

The  two  other  instruments  of  Kaiser  are  in  principle  more  like 
C.  Wolfs  apparatus,  but  may  be  used  for  chronographic  as  well  as  for 
eye-and-ear  observations.  {     The  first  of  them  has  several  arms  fixed  on 

*  Tiidschrift  Yoor  de  Wis  -  en  Naturkundige  Wetenschappen,  xv.,  page  9.  • 
t  '*  be  volledige  bepaling  yan  perBonlijke  fouten  bij  sterrekundige  waamem- 
ingen,"  in  the  xr.  vol.,  page  173,  of  the  YexBlagen  en  Mededelingen  der  K. 
Akademie  van  WetenflGhapi>en,  Af deling  Naturkunde  (Amsterdam,  1863).  As  it 
was  found  that  this  paper  was  verv  little  known  on  account  of  the  language,  the 
apparatus  alone  was  again  described  in  the  Archives  N^erlandaises  des  Sciences 
•xactes  et  naturelles,  vol.  i.,  Hague,  1866. 

X  The  first  of  them,  as  well  as  obsenrationB  made  with  it,  are  described  in  the 
'^Yerslagen  en  Mededelingen  e.  o.,"  n.  series,  vol.  U.,  pp.  216  and  foU.  (1868) : 
a.x.A.  PBoc,  8BB.  n.,  VOL.  n.,  sciENci.  3  E 


492  Proceedings  0/  the  Soyal  Itieh  Academy. 

a  perpendicular  axis,  which  by  a  simple  small  clockwork  can  be 
tamed  aronnd  itself.  Each  arm  carries  on  the  end  a  lamp  which,  by 
the  help  of  a  screen  with  a  small  hole  in  it,  and  a  lens,  can  produce  an 
artificicu  star,  which,  by  the  rotation  of  the  axis,  passes  across  a  wire 
represented  by  a  very  thin  strip  of  black  paper  pasted  on  a  piece  <^  oil 
paper,  curved  cylindhcally,  and  opposite  which  a  small  telescope  is 
placed.  In  the  moment  one  of  the  stars  is  bisected  by  the  strip  of  paper, 
an  electric  current  is  made.  This  is  done  by  a  copper  fork,  witii  two 
prongs  fixed  at  the  end  of  the  arm^  and  at  the  same  time  touching  two 
drops  of  quicksilver  in  which  the  conducting  wires  end.  The  fwks 
may  be  moyed  a  little  by  screws,  and  must  be  adjusted  car^ully, 
BO  that  they  establinh  the  current  exaetly  when  the  star  is  placed 
behind  the  wire. 

The  second  instrument,  which  at  present  is  most  in  use,  is  only  a 
modification  of  the  first  one.  It  has  only  one  arm,  which  by  clock- 
work is  drawn  from  one  side  of  a  mahogany  board,  in  which  one  end 
of  it  (that  at  which  the  lamp  is  placed)  is  fixed.  The  velocity  of  the 
motion  can  be  easily  altered  (as  also  in  the  former  instrument).  At 
the  free  end  of  the  axis  is  a  lens,  which  causes  an  image  of  a  small  hole 
m  a  screen  before  the  lamp  to  hH  on  a  piece  of  oil  paper  (curved  as  a 
cylinder)  on  which  any  number  of  dark  perpendicular  lines  may  be 
drawn.  Within  reach  of  the  observer  (as  he  stands  before  the  tele- 
scope) is  a  string,  by  which  he,  when  a  transit  is  over,  can  bring  the 
arm  back  to  its  ori^nal  position  (hereby  winding  up  the  clock  again), 
80  that  a  new  transit  may  take  place.  The  metallic  contact  is  here,  as 
in  the  former  instrument,  produced  by  a  drop  of  quicksilver,  but  this  is 
placed  at  the  end  of  the  arm,  and  accordingly  moved  along  with  it, 
while  the  thin  brass  wires  which  successively  dip  themselves  into  the 
drop  are  fixed  on  a  brass  arch,  on  the  mahogany  board.  These  wires 
are  leaning  heavily  against  small  levers,  which  may  be  moved  a  very 
little  around  their  centre  by  means  of  screws.  In  this  way,  each 
contact  apparatus  may  be  carefully  adjusted.  The  instrument  may  be 
used  for  either  kind  of  transit  observations;  the  different  electric 
currents  may  be  arranged  for  the  method  of  observing,  by  a  commu- 
tator, without  any  loss  of  time. 

L  slight  modification  of  this  apparatus  has,  under  the  name  of  time- 
ooUimator,  been  much  in  use  on  the  Continent,  only  having  a  strip  of 
metal  instead  of  the  quicksilver  drop.* 

We  have  now  given  a  short  description  of  all  the  instruments  for 
finding  personal  errors  which  have  come  into  practical  use.f    It  is 

'*  IJeber  sinen  neuen  Apparat  snx  absoluten  Bestiinmung  von  penonlichen  Fehlem 
bei  astron.  Beobachtungen."  Both  isatniments  are  8hortlv  deBcribed  in  the' 
Annals  of  the  Obseiratory  in  Lejden,  ii.,  1670,  pp.  19  and  foil.  (BeschzeibiUQig 
der  2eitcollimatoren  der  Stemwarte  in  Leiden). 

*  Bericht  der  Conferenz  der  Europaischea  Gxadmessung,  Berlin,  1867.  Annual 
Beporta  of  the  Pulkowa  Obaerratoiy  (irahzetberichte^  (b.c.,  1869,  page  8 ;  1870, 
pageg. 

t  Professor  Harkness  has  suggested  a  very  simple  apparatus  (Bepozt  on  the 


Dreyer — On  Astronomical  Tramit  Obsermtians.        493 

^iifficult  to  say  whether  these  instruments  answer  their  purpose  per- 
fectly. £ach  single  one  of  them  must  of  course  be  most  carefully 
examined,  in  order  that  constant  errors  in  its  results  may  be  detected, 
and  their  causes  done  away  with.  When  this  has  been  done  (as  in  the 
case  of  C.  "Wolf's  apparatus),  there  is  no  reason  for  not  relying  upon 
the  exactness  of  the  results  obtained  with  it,  within  a  reasonable  de* 
igree.  And  several  of  these  instruments  have,  by  a  careful  construction 
of  aU  the  details,  furnished  us  with  results  which  agree  extremely 
well.  Kaiser,  for  instance,  found,  with  his  first  instrument,  the  pro- 
bable error  in  a  single  determination  (that  is,  by  a  single  wire  transit) 
«=  ±  0*'081,  from  the  results  of  four  observers,*  while  Wolfs  apparatus 
^ves  the  probable  error  of  a  double  observation  over  one  wire 
«  ±  0''038.f  The  possibility  of  the  existence  of  constant  errors  in  the 
results  is  certainly  not  excluded  by  this,  nor  by  another  control  which  has 
been  tried  by  comparing  the  results  of  artificial  transits  with  those  of 
real  ones.     We  give  the  following  examples  here : — 

Apparatus -stai'8=  0**035  Plantamour  and  Hirsch. 

0  -02  Albrecht  and  Van  Hennekeler. 

0  -004  Albrecht  and  Yalentiner. 

0  '03  Tietjen  and  Valentiner. 

0  -002  Backlund  and  Yalentiner. 

All  these  differences  are  within  the  degree  of  exactness  possible  to 
be  attained,  as  we  shall  see  presently.  But  artificial  stars  have  not 
always  agreed  so  well  with  the  real  ones  as  in  the  determinations  of 
personal  equations  which  we  have  just  quoted.  There  appeared,  for 
instance,  during  the  determination  of  the  difference  of  longitude 
between  Leyden  and  Brussels,  in  1868,  a  perfect  discordance  between 
the  transit  instruments  and  the  time-collimator ;  but  the  observations 
with  the  former  instrument  differed  just  as  much,  inter  se,  and  there 
can  hardly  be  any  doubt  that  a  special  cause  of  variation  in  the  per- 
sonal equations  has  influenced  the  observations.^  The  mistrust  in 
his  own  apparatus  which  Eaiser,  by  this,  was  led  to  express,  §  was 
therefore  apparently  unfounded,  and  the  results  furnished  by  time- 
collimators  may  be  considered  as  very  fairly  representing  the  true 
errors  of  the  observer. 

After  having  considered  the  accuracy  of  artificial  transits,  it  is 
natural  to  test  tiie  degree  of  exactness  which  may  be  attained  in  de- 
terminations of  personal  differences  by  means  of  simultaneous  observa- 


^ifference  of  longitude  between  Washington  and  Havanna,  1870,  page  13),  but  we 
^o  not  know  of  anv  published  observations  taken  with  it.  A  proposal  of  Dr.  £• 
Kayser's  (Astron.  Kachrichten,  Ko.  1665)  seems  peifectij  impracticable. 

*  Veisbtgen  en  Mededelingen»  xv.,  1863,  page  207. 

t  Annales  de  rObservatoire  Imperial  de  Paris,  t.  viii.,  page  178. 

}We  shall  further  on  consider  this  eircunstance  fully. 
Annalen  der  Stemwarte  in  Leiden,  ii.,  page  163. 

3E2 


494  Proceedings  of  the  Boyal  Irish  Academy, 

tions  with  a  transit  instrument.  The  greater  nnmber  of  obserrations 
which  may  be  consulted  for  this  purpose  allow  us  to  enter  more  fuUj 
into  this  research. 

When  we  want  to  find  a  general  expression  for  the  probable  error 
of  a  personal  equation,  deduced  from  simultaneous  observations  of  a 
single  star  across  the  two  halves  of  the  system  of  wires,  we  must  take 
into  account  a  circumstance  which  has  been  experienced  in  nearly 
every  series  of  observations.  We  allude  to  the  fact  that  a  far  greater 
uncertainty  in  the  value  of  the  equation  is  found  by  comparing  the 
results  of  different  stars  with  one  another,  than  might  be  expected 
from  the  accordance  between  the  transits  of  one  star  over  the  different 
wires.  It  must  be  supposed  that  a  new  cause  of  errors  arises  from 
the  observer's  passing  from  one  star  to  another,  or  that  the  observer^ 
in  the  intervals  between  the  observations,  gets  out  of  practice,  and 
each  time  has  to  form  for  himself  a  new  habit  of  estimating  the  tran- 
sits. G.  A.  F.  Peters  finds,  for  instance,  as  mean  of  five  results,  the 
probable  error  of  a  personal  difference  :* — 

By  comparing  the  Bv  comparing  the 

tingle  wires  reduced  to  the  results  of  different  stars 

middle  wire.  with  the  mean  of  them. 


-  Eye  k  Ear.  Chronograph.  Eye  k  Ear.  Chronograph. 

±0'071.  *0'051.  ±0--141.  ±0-061. 

It  has,  besides,  been  remarked  by  experienced  astronomers,  that 
the  transit  over  the  first  wire  often  does  not  agree  as  well  as  the 
others  do,  after  having  been  reduced  to  the  middle  one,  and  it  is,  there- 
fore, not  improbable  that  zone  observations,  which  sometimes  only  are 
made  over  one  or  two  wires,  may  be  affected  by  constant  errors.f 

For  these  reasons  we  cannot  but  approve  of  the  expression  for  the 
probable  error  of  a  personal  equation  found  by  one  star,  which  ha» 
been  proposed  by  Dr.  Albrecht:J 

JP  =  ^»  +  ^, 

in  which  A  is  the  probable  error,  found  by  comparing  the  transits  over 
the  single  wires  with  one  another,  and  E  the  error  produced  by  the 
variation  of  the  equation  in  going  from  one  star  to  another.  As  we 
here  only  consider  the  most  common  method  of  finding  a  personal 
equation,  we  may  suppose  that  each  observer  observes  »  wires,  and 


*  Astronomische  Nachrichten,  vol.  xliz.,  nage  27. 

t  See  Argelander'a  remarks  in  **  Yierteljahnachrift  der  Astronomischen  Gesell- 
•chaft,"  vii.  (1872).  page  16. 

I  Ueber  die  Bestimmung  von  Lllngendifferenzen  mit  Hiilf e  des  Elektrischen 
Telegraphen,  Leipzig,  1869,  page  26. 


Dreyer — Oil  Astronomical  Transit  Observations,        495 

'trhat  their  probable  errors  of  a  transit  oyer  one  wire  are  respectively 
-ci'  and  a".    We  find  then— 


V  W  ^  W    y    ** 


Ab  the  probable  error  in  a  single  wire-transit,  for  experienced  ob- 
-servers,  generally  amounts  to  nearly  the  same  quantity,  we  may  in 
-the  above  formula  introduce  a  =  J(a'  +  a")  instead  of  a'  and  a".  Wc 
have  then — 


A  = 


V»' 


•and  accordingly  (as  there  is  no  reason  why  JS  should  be  dependent  on 
the  number  of  wires) — 


jfn 


■m- 


+  £^. 


W  is  here  the  probable  error,  which  appears  from  the  accordance 
between  the  results  of  different  stars.  From  this  we,  therefore,  find 
the  probable  uncertainty  in  a  personal  equation,  arising  from  the  ob- 
4Berver's  passing  from  one  star  to  another — 


■k 


If  wc,  for  instance,  from  the  observations  given  in  the  Report  on 
ihe  determination  of  the  difference  of  longitude  between  Berlin  and 
Lund,  compute  the  value  of  E^  we  may  either  deduce  W  from  the  de- 
viations of  the  single  values  of  the  equation  between  the  observers 
(Yalentiner  and  Backlund)  from  the  average  value  for  one  night,  or 
we  may  put  all  the  observations,  made  on  different  nights,  together, 
and  deduce  ^from  their  accordance  with  the  mean  of  them  all.  In 
the  former  way  I  find  as  mean  of  four  nights'  results — 

^^O-OeSandJ^-O-OSS; 

4ind  in  the  latter  way — 

W^  0-066  and  J&=  0"050. 

Dr.  Albrecht  has,  in  his  above-quoted  book,  computed  E  from  a 
number  of  observations ;  we  have  computed  it  from  several  others,  and 
find  that  chronographic  observations,  on  an  average,  give  about  0*Q4 
as  the  value  for  Ey  whether  we  compute  ^in  one  or  the  other  of  the 
Above-mentioned  ways.  As  the  eye-and-ear  method  is  now-a-days 
very  seldom  used  for  determinations  of  longitude,  it  does  not  furnish 
us  with  such  rich  materials  for  the  calculation  of  J?  as  the  chrono- 


496  Proceedings  of  (lie  Royal  Irish  Academy. 

graphic  method  docs ;  the  Tfdties  for  E  (0**06,  computed  in  the  first 
way,  and  0"05,  in  the  second  way,)  are,  therefore,  rather  nnceitain. 

It  does  not  seem  that  any  considerahle  element  of  change  enters 
into  the  personal  equation  hy  the  passing  from  one  night's  ohscrva- 
tions  to  another.  But  we  shall  see  afterwards  that  a  personal  error  is 
not  an  absolutely  invariable  quantity,  and  it  is,  therefore,  in  any 
case,  of  importance  to  extend  a  determination  of  it  over  a  greater 
number  of  nights.  With  respect  to  time-coUimators,  we  possess  tea 
few  obserrations  to  deduce  a  trustworthy  yalue  of  ^from  them.  But 
the  artificial  observations  are  certainly,  in  this  respect,  not  essentially 
different  from  the  real  ones,  as  experiments  made  in  Loyden  and  in 
Berlin  have  shown.* 

11. 

After  having  considered  the  different  ways  in  which  an  observer** 
personal  error,  or  two  obseiTcrs*  personal  equation,  can  be  found,  we- 
shall  now  try  to  find  what  general  results  can  be  derived  from  the 
great  number  of  observations  and  remarks  upon  this  subject,  which 
are  scattered  about  in  the  annals  of  different  observatories,  and  in 
papers  about  determinations  of  longitude,  etc. 

The  first  important  question  which  is  to  be  answered  is,  whether 
the  error  is  constant  or  not  ?  "When  we  compare  several  values  of  an 
error,  found  at  different  times,  with  each  other,  of  course,  only  such 
deviations  can  be  considered  as  real  variations,  which  are  too  great  to 
be  caused  by  the  common  uncertainty  in  a  transit  observation.!  We 
have  already  mentioned  the  regular  variation  in  the  equation  Bcssel- 
W.  Struve,  which  seemed  to  arise  from  changes  in  Bessel's  large 
personal  error.  Another  instance  of  such  a  regular  variation  is  tha 
eye-and-ear  ocjuation  between  Main  and  llogerson  in  Greenwich. 

In  1840  M.  -  R.  was  =  -  0'15 


1841 

+  0-08 

1843 

+  0-20 

1844 

+  0-18 

1845 

+  0-20 

1846 

+  0-26 

1847 

+  0-35 

1848 

+  0*37 

1849 

+  0-39 

1850 

+  0-45 

1851 

+  0-47 

1852 

+  0-63 

1853 

+  0-70 

*  Albrecht,  l.e,  page  32.— The  probable  uncertainty  i?,  for  a  single  day,  waafoimd 
»  i  0«-0l8,  while  natural  trannts,  taken  by  the  same  obserren,  gave  E^±  0«H>26. 
The  circumstance  that  a  real  star  moyes  more  unsteadily  than  an  artificial  one,  may 
have  contributed  to  make  the  latter  value  of  E  larger  than  the  former  one. 

^  Valuable  Investigations  of  the  exactitude  in  transit  observationfl  have  been 


Dreyer — On  AHtrofhomical  Transit  Obaervatwiis.       497 

ThiB  reg;ular  Yariatio&  is  really  surprising.  There  are  several  otlie'' 
oxmnpies  to  be  found  in  the  Greenwich  observations,  but  none  bo 
striking  as  the  above-mentioned  one ;  for  instance,  the  equation  W. 
Xllifl  -  Bogerson  was — 

In  1846    -O'll 

„  1847     -  0  -22 

„  1849     +  0  -12 

„  1850     +0  -45 

„  1861     +  0  -36 

„  1852     +  0  -44 

„  1853     +  0  -62 

Trom  these  two  examples  we  learn  that  it  was  Mr.  Eogcrson 
whose  error  was  gradually  increasing  in  the  course  of  years.  On  the 
other  handy  there  may  be  found  examples  of  a  nearly  peiiect  immu- 
tability, but  most  commonly  a  personal  equation  will  be  found  to 
vary  a  little,  without  following  any  distinct  law.  In  order  to  illus- 
trate how  the  relations  of  two  observers  can  be  at  different  epochs,  I 
have  promiscuously  taken  the  following  specimens  from  the  Green- 
wich observations : — 


Eye- 

1 
and-Ear  Mbthod.     1 

1 

Chronograph  Method. 

Dunkin 

Main 

Dunkin 

Stone 

Dunkin 

Year. 

and 

and 

Year. 

and 

and 

and 

' 

Heniy. 

Henry. 

Criswick. 

T.  tllis. 

Stone. 

1841. 

_ 

-  0-09 

1856. 

-  0-03 

_ 

1842. 

— 

-0-01 

1866. 

-0-10 



— 

1843. 

— 

-0  -02 

1857. 

-0-10 



— 

1844. 

+  0-30 

-0  06 

1858. 

-0-08 



— 

1846. 

-0  -15 

-0-12 

1869. 

-0  -13 



— 

1846. 

0  -00 

-0  -06 

1860. 

-0  -14 

+  0«-02 

+  0-07 

1847. 

+  0-24 

-0-03 

1861. 

-  0-16 

0.  00 

+  0  -13 

1848. 

-0  -01 

-0  -04 

1862. 

-  0  -16 

+  0  '01 

+  0  -14 

1849. 

0-00 

-0-06 

1863. 

-  0-16 

-  0    02 

4  0  -14 

1860. 

-0-08 

-Oil 

1864. 

-0  -12 

+  0  -04 

+  0  -13 

1851. 

-0  -11 

-Oil 

1866. 

-0  -12 

4  0    06 

4  0  -09 

1852. 

-0  -13 

0  -00 

1866. 

-0       : 

+  0  -12 

+  0-04 

1853. 

-0   12 

+  0-03 

1867. 

-0   13 

+  0  -13 

+  0  -02 

1854. 

-0-17 

— 

1868. 

-0-10 

+  0    13 

4  0  -06 

1869. 

-0   11 

+  0   17 

+  0  -03 

1870. 

-0  -11 

-0   01 

4- 0-17 

It  has  often  bfeen  said,  that  a  large  personal  error  in  many  cases 
can,  by  practice,  be  reduced  to  a  considerably  smaller  one.     C.  "Wolf 


imdeitaken  by  Pape  (Astr.  Nachr.,  liv.),  Dunkin  (Monthly  Notices,  R.A.S.,  xx., 
zxiv.)  and  Albrecht  (Ueber  die  Beatimmmig  von  Lkngendifferenzen,  page  8). 


498  Proceedings  of  the  Boydl  Irish  Academy, 

reports,  for  iimiaiice,  that,  during  the  first  three  months  he  used  hu 
apparatus,  he  found  an  error  » -|.  0*-3,  but  that  he,  by  constant  prao> 
tice,  reduced  it  to  +  O'-ll,  at  which  rate  it  continued  for  more  thaa 
six  months.*  He,  therefore,  recommends  young  astronomers  to  be 
'^  educated"  by  practising  with  the  artificial  apparatus,  as  large  errors, 
'  eventually  appearing  in  this  way,  may  be  diminished,  when  the  ob- 
server has  remarked  their  existence.  Kaiser  has  been  of  the  same 
opinion,  and  has  always  kept  his  apparatus  ready  for  work.  They 
have,  however,  been  very  little  used,f  and  it  is  still  doubtful  whether 
such  an  ''  education  "  is  of  much  use.  Of  course,  the  apparatus  ought 
to  be  very  carefully  adjusted  during  such  exercises,  and  experienced 
astronomers  (who,  it  is  to  be  supposed,  are  not  in  want  of  any  such 
^'education")  ought  to  observe  with  them  at  the  same  time.  It 
is  not  improbable  that  the  personal  error  may  be  changed  by  practice, 
in  the  eye-and-ear  method,  as  well  as  in  the  chronographic  method ; 
indeed,  my  own  experience,  however  limited,  makes  me  inclined 
to  think  60.  We  know  that  a  perfectly  unexperienced  observer^a 
error,  within  a  very  short  interval  of  time,  even  on  one  and  the  same 
evening,  has  changed  considerably;}  and  besides,  an  observer  has 
oft4*n  himself  felt  that  he  performed  a  certain  act  (for  instance,  the 
touching  of  the  key)  too  early  or  too  late,  and  when  he  has  found 
this  out,  it  is  comparatively  easy  to  correct  the  fault.§  But  it  seems 
to  be  but  very  seldom  that  such  a  case  happens,  and  until  experience 
has  taught  us  otherwise,  it  must  be  considered  as  very  doubtful  whe- 
ther an  **  education,"  such  as  the  one  above  mentioned,  is  of  much  use. 
It  is  cci*tainly  an  unpleasant  circumstance  that  personal  equations 
and  errors  are  often  variable,  as  one  may  fear  that  the  value  used 
for  the  reduction  of  a  series  of  observations  is  not  the  right  one,  if  it  is 
not  found  exactly  at  the  time  when  these  observations  were  made, 
which  is  not  always  possible ;  for  instance,  at  determinations  of  longi- 
tude. The  invention  of  the  chronographic  method  was  about  twenty- 
five  years  ago  hailed  with  pleasure,  as  it  was  expected  that  the  per- 
sonal error  by  this  method  should  become  more  constant,  as  well 
as  smaller.  II     But  these  expectations  have  only  partly  been  realized, 

*  Annales  de  rObservatoire  de  Paris,  M^m.,  t.  viii.,  p.  171. 

t  Annalen  der  Stemwarte  in  Leiden,  ii.,  p.  26. 

X  In  the  Mcmoircs  des  AstronomeB  de  Poulkova,  t.  ii. :  ExpM.  Chronmn. 
de  1845,  p.  52,  there  is  mentioned  a  Lieutenant  Alezandrow  of  the  topographic  corpSy 
whose  error  (found  by  comparisons  with  the  other  experienced  members  of  me 
expedition)  varied  enormously.  It  seemed  as  if  A.  only  for  a  few  hours  kept  the 
same  custom  in  observing,  but  that  his  error  changed  (often  0»-3  or  0«-4)  when 
there  was  a  larger  interval  between  the  different  observations.  It  was  at  first 
expected  that  A.  by  practice  could  become  more  regular,  but  this  was  not  the  case. 

f  So,  for  instance,  when  the  chronographic  method  was  introduced  in  Leyden, 
(Kaiser,  Yerslagon,  ii.,  p.  232).  We  shall  afterwards  see  how  an  excellent 
observer,  Schnnfeld,  in  the  course  of  years,  has  changed  his  way  of  estimating^ 
transits  of  nebulec,  when  it  had  been  remarked  that  his  right  ascensions  were 
too  small. 

II  W.  C.  Bond,  in  the  Eeport  of  the  British  Assoc.,  1851. 


Dreyer — On  Astrofumical  Transit  Obaermtions.       499 

«nd  in  this  respect  the  new  method  is  not  much  snperior  to  the  old  one, 
except  that  very  large  errors,  as  Bessel's,  never  have  been  foond  by 
the  chronographic  method.  However,  the  personal  equation  or  error 
by  the  new  method  is  most  commonly  very  different  from  that 
oi  the  old  one,  as  might  be  expected  from  the  great  difference  between 
the  two  methods.     The  following  examples  show  this : — 


£ye-and-£ar  Method,  j  Chronograph  Method. 


Bunkin-HughBreen,     .     .     . 

Dunkin  —  Henry, 

Dunkin-Todd,* 

CriBwick-Lynn,t  ..... 

Weiaa-Forater,* 

Absolute  persoiial  error:  Kam, 
„  „  „  Hennekeler, 

„  „  „  F.  Kaiser,} 


-  0-14 


-0 
+  0 
-0 
-0 
+  0 
+  0 
-0 


17 
01 
37 
27 
•16 
12 
14 


+  0«-09 
+  0-01 
+  0-05 
-  0 
0 
-0 


14 
00 
•03 


-0-07 
-  0-07 


It  is  an  advantage  in  the  determination  of  absolute  errors  that 
one  is  able  to  see  which  of  the  observers  changes  his  way  of  estimating 
transits,  while  a  determination  of  personal  differences  only  shows  that 
one  of  the  two  observers  (or  both  of  them)  has  a  different  way  of 
observing  by  the  two  methods. 

Considering  the  importance  of  the  question  about  the  constancy  of 
personal  errora,  especially  in  determinations  of  loDgitudc,  we  shall  here 
oxamine  a  case,  in  which  this  question  was  investigated  in  a  very  nice 
and  remarkable  way,  which  has  hitherto  not,  I  think,  been  noticed  sufE- 
ciently.  For  the  determination  of  the  difference  of  longitude  between 
Gotha  and  Leipzig  the  eye-and-ear  method,  as  well  as  the  chrono- 
graphic method,  was  used  by  the  two  observers,  Auwers  andBruhna.|| 
On  eight  evenings  the  culminations  of  a  certain  number  of  standard- 
stars,  observed  with  eye  and  ear,  were  by  both  observers  compared 
-with  the  registered  culminations  of  another  group  of  stars,  taken  from 
the  same  catalogue  as  the  ffrst  stars,  and  the  two  groups  were  so  ar- 
ranged, that  the  uncertainty  in  the  rate  of  the  clock  could  have  no 
influence.  The  clock-corrections,  found  by  the  two  groups,  gave 
d  mean  difference,  which  contained  the  difference  in  the  errors  of 
the  right  ascensions,  the  difference  between  the  pergonal  errors  for 
one  observer  in  using  the  two  methods,  and  the  interval  between  the 
moments  in  which  the  contact-apparatus  of  the  pendulum  in  each 


*  Greenwich  Observations,  1854,  Introd. 
t  Greenwich  Observations,  1859. 

I  Bestimmung  der  Meridiandifferenzen,  fierlin-Wien-Leipzig.     Vienna,  1872. 
}  Verslagen,  e.  c.  2nd  series,  vol.  ii.,  pp.  229-231.    (Series  C-0). 

II  P.  A.  Hansen:  Bestimmung  der  Langendifferenz  zwischen  den  Stemwarten 
zu  Leipzig  und  Gotha,  aosgefiihrt  von  C.  Brtihns  iind  A.  Auwers.     Leipzig,  1866. 


600  Proceedings  of  the  Royal  L*i$h  Academy. 

moyement  marked  tbe  closing  of  the  current  on  the  chronograph,  and 
t^e  moments  when  the  pendulum  gave  the  audible  second-beat.  That 
the  last-mentioned  interval  was  constant  was  found  with  certainty  by 
observing  the  two  moments,  when  the  coincidences  of  the  beats  of  the 
two  ''  assisting-clocks''  (observed  by  the  ear)  with  the  beats  of  the  princi- 
pal clocks  on  both  stations,  also  observed  by  the  ear,  and  the  coincidences 
of  the  contact-signals  of  the  principal  and  assisting-clocks,  registered  on 
the  same  chronograph,  took  place.  It  was  found  in  this  way  that,  in 
a  certain  absolute  moment,  the  difference,  Leipzig  clock- time  minu9 
Ootha  clock-time,  as  found  by  the  ear,  was  always  a  little  less  than  the 
same  difference,  as  found  by  the  chronograph,  and  the  mean  deviation 
of  the  eight  evenings,  agreeing  veiy  well  with  each  other,  was  found  to 
be  =  0*'282  (/.  c,  p.  69).  It  appears  from  the  single  results  that 
both  observers  (who  twice  exchanged  their  stations)  agreed  x>cr- 
fcctly  well  in  their  estimation  of  the  differences  by  the  ear.  But  as 
the  constant  relation  of  the  two  time-scales  to  one  another  was  proved, 
the  personal  error  must  necessarily  have  changed,  if  there  appeared 
perceptible  changes  in  the  clock-corrections,  found  in  the  two  different 
ways.  And  the  following  mean  differences  between  the  two  clock- 
corrections  were  found :  — 

By  Bruhns  in  Loipzig,  0*-43  (.)  evenings).  I  By  Auwers  in  Gotha,    0«-42  (5  ergs.^ 
„        „      „  Gotiiti,     0 -aa  {4  evenings).  I   „        „       „  Leipzig,  0 '75  (5  ergs.) 

According  to  Bnihns  the  difference  between  the  registered  and  the 
heard  clock-correction  in  Gotha  was  +  0"*10  different  from  the  one  in 
Leipzig ;  according  to  Auwers,  +  0'-33.  Above  we  have  seen  that 
the  heard  second-beats  in  Gotha  came  0'*28  later  after  the  registered 
ones  than  in  Leipzig.  "VVe  see  now  that  the  ditlerence  in  estimating 
registered  and  heani  culminations  in  Bruhns'  case  has  changed  U*-18  ; 
in  that  of  Auwers*  only  0'-05. 

This  result  controls  veiy  well  the  direct  comparisons.  By  eye-and- 
ear  was  found  : — 


1806.  April  12,  in  Loipzig,  B.-A.  «  4  0»-32  ±  0«-04 
„  October  2,  „  Gotha,  „  =  +  0*11  ±0-03 
H  n        3,„      „  „    =+0-19  ±003 


(B.  -  A.,  in  Leipxig). 
■r  (B.  -  A.,  in  Gotha). 
«  0-17. 


We  see  that  it  was  to  Bruhns  the  change  in  the  eye-and-ear- 
equation  was  due,  and  probably  the  explanation  which  the  ob&ervers 
themselves  give  of  the  phenomenon  is  the  right  one.  In  Leipzig  the 
dock  gave  double  beats  (with  an  interval  of  about  one-third  of  a 
second  between  the  single  beats),  and  this  had  probably  disturbed 
Bruhns,  so  that  he  perceived  the  moment  midway  between  the 
two  beats  instead  of  the  last  one.*    It  is  a  pity  that  the  personal 


*  The  author  has  found  a  similar  anomaly  in  himself  by  taking  transits  in 
a  room,  in  which  a  mean-time  clock  and  a  sidereal  one  were  placed. 


Dreybr — On  Aetranomical  Tramit  Observathns.        601 

equation  in  the  chronograpbic  method  was  determined  only  once,  and 
a  long  time  after  (B.  -  A,  =  +  0»*11,  January  2,  1866)  in  Leipzig. 
In  the  determination  of  the  difference  of  the  longitude  between 
Leipzig  and  Gotha,  the  personal  equation  was  not  eliminated  by 
taking  the  mean  between  the  results,  found  before  and  after  the 
observers  changing  stations,  but  in  the  reduction  of  the  series  of 
observations  during  which  B.  observed  in  Leipzig,  the  equation  found 
at  this  station  was  used,  and  likewise,  in  the  reduction  of  the 
other  series,  the  equation  found  in  Gotha.  According  to  the  above- 
mentioned  experiences,  it  would  have  been  impossible  to  use  the 
common  method,  which  is  only  practicable  when  direct  comparisons 
show  that  the  personal  equations  between  the  two  observers  had  not 
changed  in  the  mean  time.  To  change  the  stations  without  examin- 
ing the  equation  at  all  (as  in  the  determination  of  the  difference  of 
longitude  between  Berlin  and  Leipzig)  seems  doubtful. 

Passing  from  the  variation  of  the  personal  error,  during  longer  inter- 
Tals  of  time,  and  in  the  different  methods  of  observing,  we  shall  now 
consider  a  series  of  circumstances  which,  imtil  a  short  time  ago,  were 
rather  enigmatical,  and  have  contributed  a  good  deal  to  make  many 
astronomers  look  upon  personal  equations  as  a  very  weak  point  in 
modem  practical  astronomy.*  We  allude  to  the  changes  in  the  personal 
errors,  which  often  arise  from  the  reversal  of  the  instrument.  In  itself 
it  sounds  absurd  that  the  position  of  the  instrument  should  have  any 
influence  upon  the  error  of  the  observer ;  but  if  we  remember  that  a 
great  number  of  such  observations,  for  which  several  observers  are 
wanted,  and  which  accordingly  require  the  determination  of  the 
personal  equations,  are  made  with  transit  instruments,  with  what  is 
known  as  a  broken  telescope,  the  matter  becomes  different,  because  the 
direction  of  the  star's  passage  through  the  field  in  such  an  instrument 
is  different  in  its  two  positions.  If  we  observe  a  star  passing  the 
meridian  south  of  the  zenith,  it  will,  in  both  positions  of  the  instru- 
ment, go  from  left  to  right  through  the  field,  but  the  inclination  of  the 
path  to  the  horizon  wiU  be  different,  depending  not  only  on  the  zenith 
distance,  but  also  on  the  position.  When  the  observer  is  at  the  eastern 
end  of  the  axis,  the  star  will  go  from  the  third  quadrant  to  the  first 
one,  and  when  he  stands  at  the  western  end,  it  will  go  from  the 
second  to  the  fourth.  A  star  which  culminates  in  the  zenith  will  go 
vertically  through  the  field,  observed  from  east  upwards,  from  west 
downwards.  Between  the  zenith  and  the  pole  the  motion  will  take 
place  in  a  similar  way  from  right  to  left. 

We  shall  first  consider  the  results  obtained  by  artificial  stars.  C. 
Wolf  has  taken  11  groups  of  observations  with  his  eye-and-ear  appa- 
ratus, each  group  consisting  of  40  transits ;  and  by  placing  a  prism 

*  From  Bruhns'  Biography  of  Encke  we  learn  that  the  latter  "  felt  disgust  at 
petsonal  equations"  (letter  to  Gerling  from  1855).    Upon  the  whole  Encke  seems 
■  to  have  heen  rather  sceptical  with  re8X)ect  to  the  attainable  exactitude -in  astronomi- 
cal observations. 


602 


Proceedings  of  the  Royal  Irish  Aeadetny. 


before  the  eye-piece,  he  made  the  star  go  homontally  in  the 
direction  during  20  transits.     The  results  are  as  follows : — 


1864. 

From  Riglit 

From  Lrft 

to  Left. 

to  Right. 

May  11 

+  0-08 

+  0-17 

12 

+  oil 

+  0  12 

12 

+  0  09 

+  016 

12 

+  0  13 

+  0  16 

June    2 

+  0  12 

+  0  18 

8 

+  0  11 

+  012 

8 

4  0  10 

+  0  16 

8 

+  0  10 

+  0-14 

July  16 

+  0  09 

+  0  13 

23 

+  0  08 

+  0-13 

23 

4-0  09 

- 

+  0  18 

Mean 

+  0-10 

+  0  14 

There  is  here  a  distinct  thoagh  slight  difference,  and  the  mean 
result  must  be  considered  reliable,  as  the  arrangement  of  the  observa- 
tions excluded  the  influence  of  faults  in  the  apparatus.*  8iniilar  very 
small  differences  were  found  with  Hirach's  apparatus  (using  the 
chronographic  method). 

Plantamour  +  O'-Ol  ±  0'-02 

Rudolph  Wolf      +  0  -04  ?  0  -01 
Hirsch  +  0  06  ±  0  03 


Ketrog.  motion 
+  direct  motion. 


It  is  remarkable  that  these  small  differences  have  the  same  sign  as  O. 
Wolfs.t 

In  Leyden  there  has  been  made  a  scries  of  experiments  with  the 
second  time-collimator,  but  only  one  of  the  observers  found  a  slightdiffer- 
ence  which  was  very  uncertain,  as  the  chronographic  method  had  only 
lately  been  introduced  at  the  observatory.  J  Researches  on  this  sub- 
ject have  also  been  made  by  Wagner,  in  Pulkowa,  with  a  time  colli- 
mator on  Kaiser's  principle,  but  his  observations,  which  he  has  been 
kind  enough  to  communicate  to  me,  and  of  which  we  shall  hear  more 
further  on,  show  no  perceptible  influence  of  the  direction  of  the  star's 
motion.  We  have  heard  of  no  other  investigations  of  this  kind  except 
of  a  series  of  transits  ot  artificial  stars  in  perpendicular  direction  (ana- 
logous to  transits  of  zenith-stara  in  a  broken  telescope),  taken  in 
Leyden,  but  the  four  observers,  all  of  whom  had  a  very  small  absolute 
error,  found  it  to  be  a  matter  of  no  consequence  whether  the  star  was 
going  upwards  or  downwai-ds.g     Several  observations  of  artificial  stars, 

*  Annales  de  I'Observatoire  de  Paris  (Mcmoires)  viiL,  p.  174. 

t  Determination  Tel^graphique  de  la  Difference  de  Longitude  entre  Righl-Eulmy 
Zurich  et  Neuchatcl,  Geneve  et  Bdle,  1871,  p.  187. 

X  Verslagen  en  Mededelingen  der  K.  Acaddmie  von  Wetenschappen,  2  Ber.,  ii., 
p.  23.5. 

J  Ibid. 


Dreyek — On  Astronomical  Transit  Observations. 


503 


moying  along  the  line  from  left  to  right,  under  an  angle  of  45^  and  of 
S15^  with  the  horizon,  taken  in  Leyden  and  in  Berlin,  have  given  no 
difference  at  all  hetween  the  two  directions.* 

The  result  of  all  ohservations  with  time-coUimators  seems  to  he, 
that  it  is  never  of  any  great  importance  in  which  direction  the  artifi- 
cial star  goes,  as  the  diifercnce  in  the  estimation  never  exceeds  a 
few  hundreths  of  a  second.  If  such  a  difference  really  exists  (as  in 
G.  Wolf),  it  must  arise  from  an  unsymmctrical  arrangement  of  the 
fihres  of  the  nerves  in  the  retina  of  the  eye ;  and  Wolf  really  found,  by 
looking  at  two  dots  of  ink,  made  on  a  piece  of  paper,  at  equal  distances 
from  both  sides  of  a  straight  line,  that  the  space  between  the  line  and 
the  right  dot  always  seemed  to  him,  if  he  looked  at  it  with  the  right 
eye,  a  little  larger  than  the  space  between  the  line  and  the  left  dot. 
This  experiment  shows  that  he  would  always  fancy  the  space  between 
the  wire  in  the  telescope  and  a  star  to  the  right  of  it  to  be  larger  than 
it  really  was. 

But  in  perfect  opposition  to  these  results  were  many  observations 
of  real  transits,  with  broken  telescopes,  as  by  these  differences  of  consi- 
derable size  were  often  found.  Weiss,  for  instance,  remarked,  in  1863, 
by  reducing  the  observations  for  determining  the  longitude  Leipzig  - 
Dabletz,  that  the  clock  corrections  were  different,  according  to  the 
position  of  the  instrument.  He  and  Bruhns  found  the  following  mean 
differences  :f — 

Obs.  East  minus  Obs.  West. 


Weiae. 

Bruhns. 

Eye  and  Ear 

-0-17 

+  0-07 

Chrongr. 

-0-21 

-0-10 

The  variation  of  the  personal  error  with  the  position  of  the  instru- 
ment (circle  west  and  observer  east,  or  circle  east  and  observer  west) 
may  be  seen  by  the  following  examples  which  are  found  in  Dr. 
Albrecht's  book  about  determinations  of  longitude  (pp.  21-2).  The 
observations  were  made  by  the  chronograph,  each  observation  com- 
prising 5  wires : — 

1.  Tbaksit  Ikstbuvbkt  nr  Leipzig,  25th  Mabch,  1867. 


West. 

East. 

West  -  East. 

-0»-83 
-0-39 

+  0«-46 
+  0-49 

-  0-78 
-0-88 

Each  number  is  the  mean  result  from  7-9  stars. 

*  The  observations  are  given  in  Albrecht's  Bestimmung  yon  Langeadifferenzen^ 
Leipzig,  1869,  p.  20. 

t  Astr.  Nacnrichten,  Ixvxii.,  No.  1668. 


504 


Proceedings  of  the  Boyal  Irish  Academy. 


2.  Tra27sit  Instkuxsnt  nr  Bbrldt. 


Albrecht  - 

•  TlBTJEW. 

!                AlBRVCHT  -  YALRMTISrER. 

1867. 

West. 

East. 

W.-E. 

1    1*67. 

Vfmt. 

^t. 

W.-E. 

March   0 

-  0-27 

-  0-03 

-  0-24 

July  18 

-0-14 

+  0-13 

-0-27 

16 

-0  18 

-  0  03 

-0  16 

14 

-0-14 

+  0*09 

-0-28 

July    U 

.0-83 

-  0  16 

-0  17 

16 

-0-06 

0-00 

-0  05 

16 

-0-29 

-0  18 

-0-11 

16 

-0-03 

+  0-06 

-0  08 

16 

-0-28 

-0   14 

-0   14 

Nov.  9 

-0-12 

+0  09 

-0-21 

Sept   26 

-.0'23 

-0  07 

-0  16 

12 

-0-14 

-0-01 

-0-13 

27 

-0-06 

+  013 

-0  18 

TiBTJKX  -  VaLEXTIXRR. 


1867. 


July  13 
16 


West.  East.        W.  -  E. 


+  0-02 
+  0-06 


+  0-30 
+  0-31 


-  0-28 
-0-26 


Bach  number  is  the  mean  result  of  from  6  to  12  stars. 

But  the  following  results  were  found  in  Lund  in  Sweden,  with  the 
Leipzig  instrument,  after  the  illumination  had  been  altered* : — 


Valentixkr  - 

-  Backlund. 

x868. 

West. 

East. 

W.-E. 

June  26 
27 
28 
80 

-  0-02 
+  0  02 
-0  06 
+  0  03 

0-00 

0   00 

-0  03 

0-00 

-  0-02 
+  0-02 
-0  03 
+  0  03 

Each  number  is  the  mean  result  of  from  6  to  12  stftfs. 

Compared  with  these  results,  which  are  founded  on  numerous 
•observations,  the  researches  made  in  Greenwich  in  1852  and  1853, 
with  a  ''Binocular  eye-piece,"  become  of  less  importance,  being 
founded  on  rather  few  observations,  but  they  are  of  a  similar  nature. 
As  already  mentioned,  this  binocular  eye-piece  divides  by  a  prism  the 
rays  coming  from  the  object-glass  of  the  transit-instrument  into  two 
-pdjcts,  80  that  two  observers  simultaneously  may  observe  a  transit 


*  Bestammung  der  Langendifferenz  zwischen  Berlin  und  Lnnd.    Lund,  1870. 


Dreyer — On  Aatronofnical  Transit  Observatiofis.       505 

across  all  the  wires.    The  transits  look,  of  course,  as  if  s?en  in  a 
4K>mmon  broken  telescope.    We  take  as  examples* : — 

BOOSBSON  -  DUNKIN. 


185a. 

D.east. 

Star*. 

D.  WMt. 

Stan. 

Jan.  23, 
April  2, 
April  26, 

-  0-69 
-0-89 
-0-66 

4 
3 
3 

-  0-62 
-0-47 
-0-21 

4 
3 
3 

DuNKmr  -  Ellis. 

X853. 

D.  east.     Stars. 

1 

D.  west. 

Stars. 

Oct.  14, 
Oct.  20, 
Nov.  9, 

0-00 
-0-01 
-0  08 

3 
3 
3 

-  0-21 
-0-17 
-0-19 

3 
3 
3 

We  hare  now  seen  from  a  great  number  of  instances  that  the  diffe- 
rent direction  of  the  motion  has  no  influence  on  the  personal  error  in 
'Observations  of  artificial  stars,  but  that  the  different  position  of  an 
instrument  with  a  broken  telescope  often  has  a  very  considerable 
influence  on  the  estimation  of  the  transits.  It  is  impossible  to  explain 
this  otherwise  than  by  supposing  the  existence  of  a  disturbing  circum- 
stance in  the  instrument  itself.  Already,  eight  or  nine  years  ago,  it 
was  suggested,  for  instance,  at  the  conference  in  Berlin,  1867,  on  the 
European  measurement  of  arcs  of  meridian,  that  such  a  disturbance 
might  arise  from  an  eccentric  illumination,  causing  an  apparent 
shifting  of  the  whole  system  of  wires.  The  above-quoted  observations, 
■  taken  with  the  instrument  of  the  Leipzig  Observatory  before  and  after 
the  change  of  the  illumination,  show  clearly  how  great  an  influence 
this  had  had.  The  matter  was,  however,  not  yet  sufficiently  examined, 
as  long  as  it  was  unknown  why  the  influence  of  the  illumination  was 
a  different  one  for  different  observers.  But  the  determinations  of 
longitudes,  which,  during  the  last  few  years,  were  undertaken  in  Swit- 
zerland, have  thrown  light  on  these  phenomena,  and  the  investigations 
of  Messrs.  Plantamour,  Hirsch,  and  Budolph  Wolf  have  considerably 
elucidated  the  question  about  the  constancy  of  the  personal  error. 

These  three  astronomers  have  taken  the  observations  for  the  said  de- 
terminations of  longitude.  The  personal  equation  of  the  two  first-men- 
tioned was  several  times  determined  in  the  course  of  the  years  1868  to 
1870,  and  varied  but  little.  But  it  was  found  in  August,  1867,  in 
Zurich,  that  the  equation  (Birsch  -  E.  Wolf)  was  now  quite  different  to 


*  Greenwich  ObservationB,  1852  and  1853  (introd.) 


506  Proceedings  of  the  Royal  Irish  Academy. 

what  it  was  a  few  months  before  in  Nenf chatel.  It  was,  therefore,  emi^ 
posed  that  there  might  be  some  cause  for  this  change,  and  in  order  to 
obtain  a  certain  value  for  his  error,  Wolf  went  in  March,  1869,  to  Nenf* 
chatel,  and  took,  jointly  with  Hirsch,  observations  with  the  transit- 
circle  for  two  days.  But,  strange  to  say,  they  now  found  almost  the  same 
result  as  that  found  two  years  before  with  the  same  instruments; 
besides,  artificial  stars  had  in  1867  given  a  value  for  the  equation 
nearly  midways  between  the  two  results  of  real  transits  which  com- 
pleted the  confusion : — 

H.  -  R.  "W.  =  -  0«162  +  ©••009  by  eqnator-stan  \      in  Neufchatel, 
=  -  0  -067  ±  0  -016  „  artific.      „       j  May.  June,  1867. 
s  i>  0  *056  +  0  *009  „  equator-Stan  )  in  Zurich,  Aug.  1867. 
=  -  0  -139  ±  0  -013  „        „        „       i  inNeufchatel,March,1869.* 

This  was  not  the  first  time  that  such  abrupt  changes  had  taken 
place  when  the  personal  equation  had  been  determined  at  different 
times  with  difPerent  instruments ;  but  such  a  change  had  generally  been 
explained  by  one  of  the  observers  using  a  strange  instrument.  For 
examplef : — 

Ernest  Quetelet  -Sam  =  +  0**60  78  fttars,  tr.-eircle  in  Leyden,  August,  1866. 
•f  0 '13  artificiaJ  stars,        „         „  „  „ 

+  0  '40  transit-instr.  in  Brussels,  September,      „ 
■f  0  '16  20  stars,  mural-circle,  Brussels,  Sept.,  „ 

It  was  the  variation  of  this  equation  which  made  Kaiser  doubtful 
about  his  timc-collimators,  which  seems  strange,  as  the  real  transits, 
differed  just  as  much  in  their  results.     Another  example  is  : — 

Jamefalt  -  Fuss  =  +  0«-10,  June  27,  July  4,  \  ,«-^  p„it^,^  + 
+  0  -41,  July  7-16,  j  ^®7^'  P'llkowa.t 

Although  it  was,  therefore,  nothing  new  that  such  strange  results 
should  appear  in  determinations  of  longitude,  still,  in  the  summer  of 
1869,  Wolf  undertook  a  series  of  researches  in  conjunction  with  his  as- 
sistant, whereby  it  was  foimd  that  th«  principal  cause  of  the  deviations 
between  the  different  values  was  the  position  of  the  eye-piece.  As  is 
natural,  when  two  persons  observe  immediately  after  one  another  the 
passages  of  the  same  star  over  the  two  halves  of  the  system  of  wires, 
Hirsch  and  Wolf  had  placed  the  eye-piece  midways  between  the  two- 
positions,  which  were  convenient  for  their  eyes;  accordingly  the  eye- 
piece was  for  the  short-sighted  W.  too  far  from  the  focus,  but  for  H.'s 
normal  sight  it  was  too  near  this.  Wolf  derives  the  following  results 
from  all  the  observations  printed  in  his  ''Mittheilungen,"  page  265  : — 

*  R.  Wolf,  Astronomiache  Mittheilungen,  xxv.  (Tierteljahrssdrnft  der  Nator* 
forschenden  GeseUschaft  in  Ziiricb,  ziv.,  1869,  page  250}, 

t  Annalen  der  Stemwarte  in  Leiden,  ii.,  page  169. 

X  Bestimmung  der  Langendifferens  rwiscben  Pulkowa,  Helsingfon,  iho,  Lo« 
wisa  und  Wiborg,  von  J.  Kortazzi :   St.  Petersburg,  1871,  pp.  68-9, 


Dreyer — On  Astronomical  Transit  Observations.        507 

1.  When  the  field  of  the  telescope  is  illuminated  from  the  west, 
upper  transits  are  observed  too  early  if  the  eye-piece  is  drawn  out  too 
fu*  for  the  observer's  sight,  and  too  late  if  it  is  pushed  in  too  much. 

2.  With  eastern  illumination  the  case  is  reversed ;  the  transit  is 
taken  too  late  with  the  eye-piece  drawn  out,  and  too  early  with  it 
pushed  in. 

3.  If  the  field  is  illuminated  by  the  diffused  daylight,  the  position 
of  the  eye-piece  has  no  influence  on  the  personal  error ;  and  this  error 
is  also,  on  the  other  hand,  independent  of  the  direction  of  the  illumina- 
tion, if  the  eye-piece  is  exactly  adjusted. 

As  during  the  above-quoted  observations  by  R.  Wolf  and  Hirsch, 
the  eye-piece  had  always  been  drawn  out  too  far  for  the  sight  of  the 
former,  it  was  now  clear  why  he  had  observed  too  late  in  Neuf  ch&tel, 
where  the  illumination  came  from  the  east,  and  too  early  in  Zurich, 
where  it  came  from  the  west.*  Notwithstanding  all  this,  the  problem 
was  not  yet  solved,  as  this  effect  of  the  position  of  the  eye-piece  and  of 
the  illumination  was  unexplained,  and  besides,  how  was  it  that  Hirsch 
and  the  long-sighted  Plantamour,  in  their  numerous  determinations  of 
their  personal  equations,  had  never  remarked  such  an  effect  ?  These 
questions  were  important  enough  to  deserve  a  nearer  investigation, 
and  such  a  one  was,  therefore,  made  by  Hirsch  and  his  assistant, 
Schmidt,  in  Neufch&tel,  during  the  spring  of  1870,  as  foUowsf: — 
Each  observer  observed  a  certain  number  of  stars  over  all  the  wires, 
having  the  eye-piece  adjusted  for  his  eye  during  the  transit  across  half 
the  wires,  and  having  it  drawn  out  or  pushed  in  a  little  during  the 
transit  over  the  remaining  half.  The  eye-piece  was  in  either  case 
moved  to  an  equal  distance  from  the  normal  position,  and  the  part  of 
the  wires  observed  with  the  adjusted  eye-piece  was  constantly 
exchanged  for  another.  The  observations,  which  are  communicated  in 
the  "  Astron.  Mittheilungen,"  xxvi.,  gave  the  following  results.  By 
a  we  designate  adjusted  eye-piece,  by  d  drawn  out,  and  by  p  pushed  in. 
The  illumination  came  from  the  cast : — 


1870. 

Number  of 
Stars. 

Difference  between 
the  Transits, 
reduced  to  the 
Central  Wire. 

Mean  Error. 

Observer. 

April  20, 
April  22, 
April  25, 
April  26, 

14 
10 
14 
15 

a-rf=:  + 0-259 
a-rf  =  +0-280 
a-j^B- 0-276 
j,_rf„  + 0-464 

±  0-021 
0-019 
0-009 
0-011 

S. 
H. 

S. 

s. 

*  In  both  the  inrtrunients  in  use  the  illumination  was  from  east  or  west  sent 
down  to  the  wixes  by  a  small  mirror  under  an  angle  of  45**  with  the  axis. 

t  Determination  t^^graphique  de  la  difference  de  longitude  entre  la  station 
astronomique  de  Bighi-Kulm  et  lee  Obserratoires  de  Zurich  et  de  Keuf  ch&tel.  Gfendye^ 
1871,  pp.  171  and  foU. 

3  F 


B.  I.  ▲.  PROa,  tSR.  U.,  TOL.  n..  80IBKCB. 


508  Proceedings  of  the  Royal  Irish  Academy. 

These  numben  allow  of  no  doubt  as  to  the  reality  of  the  inflaence 
of  the  eye-piece :  besides,  the  extent  of  this  influence  mnst  be  inde* 
pendent  of  the  observer  (as  both  H.  and  S.  found  nearly  the  same 
result),  and  it  seems  to  be  proportional  with  the  distance  of  the  eye- 
piece from  its  adjustment.  The  result  found  in  this  manner  in  Nenf- 
chatel  by  illumination  from  the  eastern  end  of  the  axis  was  identically 
the  same  as  the  one  found  in  Ziirich  by  iUumination  from  the  west,  the 
transit  having  been  taken  too  late,  while  the  eye-piece  was  too  near 
the  wires,  and  too  early,  when  it  was  too  far  from  them. 

The  results  were  accordingly  in  perfect  opposition  to  the  observa*- 
tions  taken  in  Zurich,  and  it  seemed,  therefore,  that  the  placing  of  the 
lamp  at  one  or  the  other  end  of  the  axis  could  not  be  the  cause  of  the 
change  in  the  anomaly.  As  the  matter,  therefore,  seemed  worth  a  closer 
examination,  Hirsch  took  a  series  of  observations  with  his  artificial 
apparatus.*  From  these  it  was  again  seen  that  the  day  observations 
are  independent  of  the  position  of  the  eye-piece,  while  the  night  obser- 
vations showed  not  only  again  the  influence  of  the  eye-piece,  but  also 
that  the  variations  are  opposite  when  the  lamp  is  placed  east  and  west. 
And  this  time  the  influence  of  the  illumination,  strange  enough,  was  the 
same  as  that  in  Zurich,  and  opposed  to  the  one  that  only  a  few  days 
previously  had  been  found  in  Neuf chatel.  For  the  transits  were  now 
observed  with  illumination  from  the  east. 

By  H.  too  early  fon  an  average  0**18^  with  eye-piece  pushed  in. 
»  ^»    i»    »i      ( )t  i>        »i      o**iy)    ,,      ,,      ,,         ,,      „ 
„  H.   „  late     f„   „        „      0-12)    „      „      „    drawn  out. 
»»  o-    fi    »»      ( »t    »f        >i      0  **^y    tt      >»      »»         f*       ft 

But  observed  with  illumination  from  the  west,     • 

By  U.  too  late  (on  an  avcrago  0»-21)  with  eye-piece  pushed  in. 
„    S.    „early(„„     „  0-24)    „      „      „     drawn  out. 

The  question  as  to  how  the  position  of  the  eye-piece  influences  the 
observation  seemed,  therefore,  to  become  more  and  more  abstruse,  while 
the  existence  of  this  influence  was  constantly  felt  if  the  field  was 
illuminated  by  artificial  light.  What  remained  was  to  explain  the 
contradiction  between  the  Neuf  chatel  observations  of  natural  and  arti- 
ficial stars,  with  respect  to  the  direction  of  the  influence  (retarding  or 
accelerating)  for  the  same  position  of  the  lamp  and  the  eye-piece. 

An  observation  by  Hirsch  gave  at  last  the  key  to  all  the  phe- 
nomena. The  apparatus  for  the  artificial  star  was  in  Neufch^tel 
placed  before  the  meridian-mark,  and  when  the  telescope  was  directed 
towards  the  latter,  the  middle  of  the  field  was  seen  strongly  illumi- 
nated by  the  gas-flame  behind  it,  so  that  the  wire  in  the  telescope, 
across  which  l^e  transits  were  observed,  was  projected  partly  on  this 


*  Communicated  in  lus  <'  Difference  de  Longitude,  Bighi-Kuhn,"  &c. 


Dreyer — On  Astronomical  Transit  Observations.        609 

blight  cirde,  partly  on  the  dark  border  round  it,  where  it  was  seen 
only  by  the  field  illumination  in  the  telescope.  The  3rd  May,  while 
the  eye-piece  was  too  far  from  the  wire,  Hirsch  remarked  that  the  latter 
was  not  seen  as  a  straight  line,  but  as  a  broken  one,  as  the  part  which 
was  seen  on  the  bright  ground  seemed  to  be  moved  out  of  its  place  to 
the  right.  With  adjusted  eye-piece  the  line  was  seen  straight ;  with 
a  pushed-in  one  it  appeared  broken,  and  its  central  part  moved  to  the 
left.  And  this  apparent  shifting  of  the  wires  was  f oirnd  to  be  inde- 
pendent of  the  placing  of  the  lamp. 

At  once  awakened  to  this  fact,  Hirsch  soon  remarked  that  an 
observer  always  would  see  two  images  of  the  wire  if  the  eye-piece  was 
not  exactly  adjusted ;  besides  the  principal  one,  which,  from  want  of 
adjustment  appeared  diffused,  a  secondary,  much  fainter  but  sharper, 
image  was  seen.  The  latter  image  seemed  to  occupy  the  real  place  of 
the  wire,  and  the  relative  position  of  the  two  images  was  reversed  for 
the  two  motions  of  the  eye-piece.  This  gave,  evidently,  the  explan- 
ation of  the  principal  fact,  the  acceleration  or  retarding  of  the 
transits,  caused  by  the  abnormal  position  of  the  eye-piece ;  and  by 
measuring  the  distance  between  the  two  images,  by  means  of  a  mov- 
able wire,  this  was  found  =  0'*29,  or  nearly  equal  to  the  difference 
4i-d  and  a  -p  on  page  507. 

This  discovery,  however,  did  not  explain  the  observations  made  in 
Zurich,  nor  those  taken  in  Neufchatel  on  the  2nd  May.  It  had  been 
suspected  that  the  position  of  the  reflecting  mirror  in  the  telescope 
might  influence  the  phenomenon,  and  this  was  confirmed  by  an  obser- 
vation of  Schmidt  on  the  4th  May.  According  to  this,  a  change  in 
the  inclination  of  the  reflector  caused  the  secondary  image  to  change 
its  position.  While  the  reflector  (whose  inclination  could  only  be 
changed  a  little)  was  in  an  extreme  position,  he  could  see  the  image 
on  the  bright  background  of  the  meridian-mark,  and  the  other  one  on 
the  comparatively  darker  fleld-background ;  but  on  the  latter  he  could 
not  see  &e  secondary  image,  which  Hirsch  had  seen  on  the  preceding 
•day.  This  image,  however,  became  visible  when  he  turned  the  re- 
flector a  little  to  the  right;  it  changed  its  place  according  to  the 
position  of  the  eye-piece,  but  without  coinciding  perfectly  with  the 
image  projected  on  the  bright  back-ground.  After  the  reflector  had 
been  turned  still  more  towards  the  position  in  which  it  would  give 
most  light,  there  came  a  moment  when  the  two  images  in  the  part  of 
the  field  only  illuminated  by  the  reflector  had  the  same  intensity ;  when 
the  reflector  was  turned  still  more  in  the  same  direction,  the  secondary 
image  disappeared  again,  while  the  principal  one  became  more  dis- 
tinct. It  was  also  found  that  the  distance  between  the  two  images 
decreased  gradually,  while  the  eye-piece  was  approached  to  the  ad- 
justment in  which  they  coincide;  by  moving  it  beyond  the  normal 
position,  the  secondary  image  appeared  again,  but  on  the  opposite 
flide. 

All  these  results  were  confirmed  a  few  days  later  by  MM.  Planta- 

8F2 


510 


Proceedings  of  the  Bayal  Irish  Academy. 


monr  and  B.  ITolf .    The  latter  recapitnlates  the  influence  of  tk& 
reflector  in  the  following  way  :* — 


\ 

WiST                         ^ 

^                               IA«T 

A 

*■                         tTi- 

V 

•PIKCK                       * 

Place  of 
the  Lamp. 

Position 

of  the 

Reflector. 

Ificld. 

Relative  position  of  the  image  illnm.  bjr  the  reflector, 
with  respect  to  the  image  on  the  bright  ground. 

Eye-piece  drawn  out. 

E3re-piece  poshed  in. 

"West. 
East. 

1 
2 
3 
4 
6 
6 

Bright. 
Dark.t 
Bright 
Bright. 
DaA.t 
Bright. 

To  the  right. 

To  the  left. 
To  the  right. 

To  the  left. 

To  the  left. 

To  the  right. 
To  the  left. 

To  the  right. 

"We  have  here  bo  fully  described  the  results  of  the  investigations 
of  the  Swiss  astronomers,  because  it  is  evident  that  they  are  of  very 
great  importance,  not  only  for  our  knowledge  of  the  personal  error, 
but  for  practical  astronomy  in  general.  They  explain  most  probably 
the  sudden  changes  in  the  equation  of  two  observers,  which  have 
often  been  remarked,  and  they  have,  besides,  conflrmed  the  suggestion 
that  the  illumination  of  the  wires  causes  the  difference  between  the 
errors  in  the  two  positions  of  a  broken  telescope,  which  sometimes 
appear.  Two  of  the  weakest  points  in  the  art  of  observation  have 
in  this  way  been  made  clear.  And  it  is  easy  to  avoid  the  causes 
of  the  disturbances,  now  that  they  are  known.  If  the  observer  has 
only  adjusted  the  eye-piece  according  to  his  sight,  he  may  be  sure 


*  yieiteliahrB8chrift  der  NatnzfoxBchenden  Gesellschaft  in  Zurich,  zv.,  1870, 
p.  249. 

t  Only  so  in  the  Zurich  instrument,  owing  to  the  large  aperture  of  the  re* 
flector. 


Dbeyer — On  Astronomical  Transit  Observations, 


611 


that  nothing  but  his  common  personal  error  will  influence  his  obser- 
TatioDS. 

After  having  considered  the  variation  of  the  personal  error  during 
shorter  and  longer  intervals  of  time,  and  the  influence  of  the  eye-piece 
on  the  estimation  of  a  transit,  we  shall  now  turn  our  attention  to  two 
circumstances  which  may  have  a  similar  influence,  the  magnifying 
power  and  the  apparent  velocity  of  the  motion  of  the  star,  varying 
according  to  its  polar  distance.  These  two  circumstances  have  often 
been  considered  as  perfectly  identical.  Bessel,  for  instance,  tells  us* 
that  he,  acknowledging  the  importance  of  the  question  as  to  whether 
the  personal  error  varies  according  to  the  polar  distance,  had  made 
numerous  experiments  with  several  powers,  whereby  it  w^  found  to 
be  of  no  consequence  whether  he  observed  stars  near  the  equator  with 
a  power  of  180,  or  with  one  of  66 ;  and  as  stars  with  a  N.  P.  D.  not 
smaller  than  20°,  seen  with  the  former  power,  move  as  quickly  or 
more  quickly,  than  equatorial  stars  seen  with  the  latter,  he  concluded 
that  there  was  no  fear  of  faults  in  his  right  ascensions  arising  from 
the  diflercnce  in  polar  distance.  But  this  conclusion  is  not  quite 
certain,  as  C.  ^Volf  has  already  remarked, f  because  the  thickness  of 
the  wire  is  increased  by  a  higher  power,  whereby  it  may  be  difficult 
to  estimate  its  axis  in  like  manner  before  and  after  the  transit.  It 
seems,  therefore,  more  correct  to  treat  the  two  questions  separately ; 
moreover,  neither  have  been  examined  sufficiently  hitherto.  With 
respect  to  the  magnifying  power,  the  following  tables  show  the  few 
results  hitherto  published : — 

I.  Etx-avd-Eab  Method. 


Power. 

C.  Wolf. 

34 
43 

77 
133 

+  0-163 
+  0   161 
+  0  -HI 
+  0  -104 

Power. 

F.  Kaiser. 

P.  J.  Kaiser. 

Kam. 

van  Hennekeler 

50 
200 

-  0«-094 
-0   141 

+  0»032 
+  0  -018 

+  0-188 
+  0  -160 

+  0-066 
+  0  126 

*  Konigsberger  Beobachtimgen,  viii.,  p.  8. 

t  Annales  de  rObseiratoire  de  Paris,  M6moires,  t.  viii.,  p.  176. 


512 


Proceedings  of  the  Boyal  Irish  Academy. 


II.  Ghbokogkaphio  Method. 


r 

Power. 

F.  Kaij^er. 

P.  J.  KaUer. 

Kam. 

50              -  0-094 
2U0            -  0  007 

-  0*096 

-  0  061 

+  0-028 
-  0  029 

-0-074 
"  0  084 

Power. 

PI.,  itamour. 

R.  Wolf. 

Hirsch. 

70      1 
200 

-  0*063 

-  0  -039 

-  0-243 
-0-170 

-  0^164 

-  0  134 

We  see  from  this  that  the  changes  (if  such  appear  at  all)  are  very- 
small,  and  there  does  not  seem  to  exist  any  law,  as  it  would  probably 
be  too  early  to  say  that  a  higher  power  decreases  the  error,  consider- 
ing the  small  number  of  ca^es. 

With  respect  to  the  influence  of  the  declination,  there  cannot  at 
the  present  moment  be  said  an3rthing  in  general,  as  this  important 
question  has  been  very  little  examined.  In  itself,  it  is  very  impro- 
bable that  personal  equations  should  vary  much  according  to  the 
declination  of  the  stars,  as  only  the  difference  between  the  two 
observers'  dependence  could  be  visible.  And  there  is  no  reason  to 
expect  that  a  personal  error,  generally,  should  vary  regularly  according 
to  the  apparent  velocity  of  the  star,  as  even  in  rather  high  declinations 
(50°  or  60°)  the  space  passed  through  by  the  star  in  a  second  is  large 
enough  to  be  divided  with  certainty.  And  that  the  error  should  in- 
crease with  sec  8,  as  R.  Wolf  thinks  has  been  found  by  the  observa- 
tions in  Zurich,*  does  not  necessarily  result  from  them,  and  is  besides 
very  improbable,  as  personal  errors  must  arise  from  faults  in  the 
sight,  or  in  the  hearing,  or  in  the  co-operation  of  these  senses,  and 
in  the  chronographic  method,  from  faults  in  the  pressing  of  the  key. 
Faults  of  the  latter  kind,  or  in  the  hearing,  must  necessarily  be  the 
same  everywhere;  while  faults  in  the  sight,  as  already  said,  can 
hardly  change  until  in  very  high  declinations.  C.  Wolfs  observations 
show  certainly  a  regular  but  very  small  variation  of  the  error,  as  the 


•  Astron.  Mittlieilungen,  xxv.  (Vierteljahrsschrift  der  Gesellscliaft  in  Zurich,, 
ziy.),  1869,  p.  265. 


Dbeter — On  Astronomical  Transit  Observations.        513 

loUo wing  table  illustrates,  but  they  are  the  only  ones  which  have 
l^yeu  such  a  result.* 


Velocity 
^the  equato- 
rial onesx). 

Personal  Error. 

Number  of 
Complete  De- 
terminations. 

1-9 
1-6 
11 

0-7 

+  0-141  +  0-014 
+  0-120-1-0-010 
+  0  -108  ±  0  -012 
+  0  -091  +  0  -016 

6 
8 
6 
6 

Most  probably  a  velocity  greater  than  the  equatorial  one  was 
strange  to  the  observer,  and  therefore  more  likely  to  cause  an  increase 
of  the  error.  But  that  personal  errors  might  be  quite  diiferent  in 
observations  of  polar  stars,  has  for  along  time  been  suspected,  not  only 
from  Pape's  and  Peters'  observations,!  but  for  many  other  reasons. 
We  shall  here  mention  only  the  considerable  difference  between  the 
determinations  of  the  right  ascension  of  the  polar  star  by  Bessel  and 
Struve,  which  probably  arose  from  a  different  error  for  equatorial 
and  for  polar  stars.  With  still  greater  certainty  must  such  a  variation 
account  for  the  great  difference  between  Struve  and  Preuss,  which 
appeared  through  Peters'  researches  on  the  right  ascension  of  the 
polar  star,  from  the  observations  in  Dorpat.  We  know  also  from 
l^ewcomb's  '*  Positions  of  Fundamental  Stars,"  that  the  R.  A.  of  the 
polar  star  has  been  found  considerably  different  by  the  different 
observers  in  Washington ;  so  that,  for  instance,  Mr.  Thirion  differed 
more  than  two  seconds  from  Professor  Hall. 

Astronomers  who  propose  the  construction  of  standard  catalogues 
must  therefore  in  future  enter  more  fully  than  hitherto  into  an 
examination  of  their  personal  errors.  Such  a  one  has  lately  been 
undertaken  by  M.  Wagner,  Vice-Director  of  the  Russian  Central 
Observatory  in  Pulkowa,  who  has  been  kind  enough  to  communicate 
to  me  his  important  results,  of  which  I  shall  now,  with  his  permission, 
give  a  short  account. 

When  the  chronographic  method  was  introduced  in  Pulkowa,  it 
was  soon  found  that  the  right  ascensions  of  polar  stars  not  only 
depended  on  the  observer's  individuality,  but  also  on  the  method  of 


*  Aimales  de  rObseryatoire  de  Paris,  viii.,  p.  187. 
t  The  equation  Pape- Peters  was : 

Eye-and-Ear. 
for  eqnatorial  stars     -  0«'ll 
„    tne  polar  star       —0-02 
(Astron.  Nachrichten,  liv.,  p.  187.) 


Chronograph. 
-0«14 
-0-33 


514  Proceedings  of  the  Boyal  Irish  Academy. 

obBerring  (that  Ib,  using  tHe  old  or  the  new  method),  and  that  the 
appearing  differences  were  a  good  deal  larger  than  the  probable  errors 
of  a  single  observation.  Before  deducing  final  results  with  respect  to 
the  positions  of  northern  stars,  it  seemed  therefore  necessary  directly 
to  find  the  above-mentioned  differences  between  the  different  princi- 
pal observatories ;  or  better,  to  determine  the  absolute  personal  errors 
by  one  of  the  artificial  instruments.  For  the  first  reason,  M.  Wagner 
went  in  the  summer  of  1868  to  Greenwich,  where  he,  on  seven  nights, 
compared  himself  with  the  transit  observers  there;  for  the  second 
purpose,  a  time-collimator  was  placed  in  one  of  the  meridian-mark 
houses  in  Pulkowa,  so  that  the  transits  of  the  artificial  star  could  be 
observed  by  lenses  of  proper  focal  length,  in  the  large  transit  instru- 
ment. 

Polar  stars  are  in  Greenwich  still  observed  with  eye  and  ear 
alone.  As  the  observations  are  taken  by  several  observers,  M. 
Wagner  could  only  obtain  mean  results.  While  his  equation  with 
the  Greenwich  observers  for  equatorial  stars  was  very  small,*  he 
found  for  stars  near  the  pole : 

Kumber 
of  Stan. 

3 
3 
7 
5 
1 
5 

The  negative  sign  and  the  increase  towards  the  pole  seems  certain. 
This  result  became  more  interesting,  when  it  appeared  that  some  of 
the  observers  differed  more  than  others.    By  adopting  the  expression. 

sin  2^45^ 

the  f oUowing  differences  were  found : 

W.-Dunkm=-.  0"-56 


i.  p.  D. 

W.- Greenwich. 

6°  12' 

-  0'02 

4  22 

-0-51 

3  24 

-0  02 

2  45 

-0-60 

1     5 

-0-34 

1     0 

-1-14 

W. -EUis    =-0-17 


sinjKPi) 
sin  2^45' 


sinJVTi)' 
the  probable  errors  of  the  coefficients  being  respectively  =:  ±  ©"'IS, 


*  Greenwich  ObseryationB,  1868,Intiod.  (Dunkin— Wagner)  «•  ~  0*06by  ohrono- 
graphic  observataons. 


Dreter — On  Astrofumical  Transit  Observations.        615 

andss  ±  0''11.  As  it  therefore  seemed  probable  that  the  different 
observers  woidd  find  different  values  for  the  B.  A.  of  the  polar  star, 
M.  Wagner,  justly  thinking  it  of  interest  to  ascertain  this,  extracted 
from  the  Tolumes  of  ''Greenwich  Observations,"  published  before 
1869,  the  B.  A.  of  a  IJrsae  minoris  separately  from  the  observations  of 
every  single  assistant.  In  order  to  be  independent  of  the  uncertainty 
in  the  azimuth,  only  such  results  were  used,  for  which  two  consecu- 
tive culminations  were  observed  by  the  same  person.  The  following 
B.  A.B  for  1865'0  of  a  IJrsae  minoris  were  found  in  this  way : 


Bunkin, 

l»  9»  39-19 

from  58  observations 

EUis, 

58-54 

„     48 

J.  Carpenter, 

38-43 

„     30 

Criswick, 

38-12 

„     44 

Kerschner, 

37-82 

„     18 

Stone, 

36-47 

»       8 

This  has  again  confirmed  the  possibility  of  a  different  estimation 
of  transits  of  polar  and  equatorial  stars. 

The  observations  of  artificial  stars  in  Pulkowa  began  in  1870. 
The  apparatus  used  was  the  modified  time-collimator  of  Kaiser, 
manufactured  by  Tiede  in  Berlin,  and,  as  already  mentioned,  placed 
BO  that  the  circumstances  under  which  the  transits  were  observed 
were  as  much  as  possible  like  those  under  which  the  natural  transits 
were  taken.  The  following  tables  give  the  results  of  M.  Wagner's 
observations.  When  the  star  was  made  to  go  more  slowly,  a  less 
number  of  wire-transits  were  taken  than  when  the  star  was  going 
with  the  velocity  of  an  equatorial  star.  The  column  8  indicates  the 
apparent  velocity  of  the  artificial  star. 

1870.    Motion  Dibkci. 


logMiC^. 

a. 

Error  by 
Eye  and  Ear. 

Error  by 
Chronogr. 

Number 
of  Obser- 
vations.; 

Chr.-EE. 

EE+-Cbr. 

s 

002 
012 
0-46 
0-67 
Ml 
1-21 
1-66 
1-J6 

i7n6' 

40  40 
69  43 
77  39 
86  33 
86  28 

88  23 

89  0 

-  0-018 
-0-001 
+  0  028 
-0  039 
+  0-06 
+  0  02 
+  0-22 
+  0-31 

-  0-089 

-  0  063 
-0  088 
-0  166 
-0  12 
-0-31 
-0-30 
-0-24 

3i 
7-6 
8 
7 
3 
6 
7 
7 

-  0-070 

-  0  062 
-0  116 
-0  126 
-017 
-0-29 
-0-62 
-0-66 

-0-063 
-  0  032 
-0-030 
-0-102 
-0  036 
-0-17 
-0  04 
+  0-03 

file 


Proceedings  of  the  Boyal  Irish  Academy, 


1871.    Motion  Betboobade.* 


loff.tec.  . 

5. 

Error  by 

Error  by 

Namber 
of  Obser- 
vations. 

Chr.-EE. 

EE.  +  Chr. 

Eye  and  l£ar.  ■     Chronogr. 

1 

a 

006 
0-41 
0-67 
116 
1-50 
1-77 

29'»26' 
67    6 
77  39 
85  57 

88  11 

89  2 

-  0-055 

-  0  -28 

-  0  001 
+  004 
+  0-14 
+  0-46 

-  0-061 

-  0  *085 
-0112 
-0-28 
-0-32 
-0  02 

7 
8-9 

8 
7-6i 

8 

8 

-  0»  006 

-  0  057 
-0111 
-0-32 
-0-46 
-0-48 

-  0-053 

-  0  057 

-  0  066 
-0  14 
-0  08 
+  0  -22 

M.  Wagner  considers  these  results  worthy  of  some  credit,  as  the 
differences  between  his  rej^istered  transits,  f  and  those  observed  with 
eye  and  ear,  agree  very  well  with  what  has  appeared  from  his  observa- 
tions of  the  real  stars.  The  constant  faults  (caused  by  defects  in  the 
apparatus)  can,  for  equatorial  velocity,  only  amount  to  a  few  thoa- 
sandths  of  a  second ;  for  the  slowest  motion,  they  may  be  considerably 
larger,  on  account  of  faults  in  the  adjusting  screws,  but  the  mean 
results  contained  in  the  last  column  of  the  above  table  may,  notwith- 
standing this,  be  considered  as  a  very  fair  approximation  to  the 
truth. 

The  last  question  we  now  have  to  answer  is,  has  the  apparent 
brilliancy  of  the  objects  observed  any  influence  on  an  observer's  esti- 
mation of  its  transit?  That  a  personality  is  distinctly  visible  in. 
observations  of  the  first  and  second  limbs  of  the  sun  or  the  moon,  has 
lately  been  shown  by  Mr,  Dunkin,  in  Greenwich,  in  two  papers  laid 
before  the  Royal  Astronomical  Society, J  the  personal  errors  being 
detected  in  the  tabular  errors  of  the  K.  A.  of  the  moon  and  of  the  sun. 
The  different  habits  of  observing  these  two  celestial  objects  by  the 
four  principal  observers  in  Greenwich,  arc  essentially  the  same  in  the 
observations  of  both  of  them,  as  the  following  table  shows  :§ — 


*  Corresponding  to  the  direction  of  the  motion  of  a  star  between  the  Pole  and 
the  Zenith. 

t  To  be  found  in  the  column  headed :  "  Chr.  -EE." 

t  On  Personality  in  observing  Transits  of  the  limbs  of  the  Moon — "  Monthly 
Notices,"  Vol.  xxiz.,  p.  259.  On  Personality  in  observing  Tranidts  of  the  first  and 
Becond  limbs  of  the  Sun. — Ibid.y  xxxv.,  p.  91. 

{  For  the  moon  Mr.  Dunkin  has  not  only  used  the  observationB  taken  with  the 
transit-instrument  (quoted  here),  but  also  those  token  with  the  altazimuth,  which, 
upon  the  whole,  give  similar  results,  although  made  under  quite  different  circum- 
■tances. 


Dretkr — On  Asfronamical  Tramit  Observations,        517 


Tabular  Ekbobs  of  II.  A. 


Of  the  Sun. 

Op  the 

Moon. 

ist  Limb. 

and  Limb. 

xst  Limb. 

2nd  Limb. 

C.-ElUfl,  .... 
C- J.  Carpenter,     . 

+  0-062 
+  0-103 
+  0-160 

+  0-002 
+  0  -019 
-0  -001 

+  0  -034 
+  0-112 
+  0-132 

+  0-032 
+  0  077 
+  0  -038 

There  can  hardly  be  any  doubt  that  this  personality  principally 
arises  from  the  irradiation,  as  it  is  a  well-known  fact  that  the  diameter 
of  the  sun,  as  well  as  that  of  the  moon,  is  measured  differently  by 
different  observers,  as  also  by  different  telescopes.  But  there  is  ano- 
ther circumstance,  the  condition  of  the  atmosphere  and  the  quality  of 
the  images  (which  depends  thereon)  whose  great  importance  for  obser- 
Tations  of  such  very  luminous  objects  must  not  be  undervalued.  The 
observations  of  the  sun  made  in  Pulkowa  by  Wagner  and  Gylden 
(especially  by  the  former)  show  very  distinctly  that  the  apparent 
diameter  of  the  sun  increases,  as  the  images  get  worse,*  and  the  circum- 
stances under  which  the  limbs  of  the  sun  and  the  moon  are  taken 
differ  therefore,  in  every  respect,  from  those  of  star  observations,  so 
that  personality  in  the  former  cannot  be  treated  from  the  same  point 
of  view  as  in  the  latter. 

While  the  observer's  individuality  thus  has  a  different  influence  in 
observations  of  the  different  limbs  of  the  sun  and  moon,  we  must 
leave  it  to  the  future  to  decide  whether  observations  of  faint  stars, 
compared  with  those  of  brighter  ones  show  a  similai'  anomaly  (that  is, 
a  change  in  the  common  personal  error)  or  not.  It  is  impossible  to 
find  anything  respecting  this  question  by  examining  any  of  the 
published  observations  of  personal  equations,  as  these  only  extend 
over  three  or  four  of  the  first  classes  of  magnitude,  where,  no  doubt, 
a  distinct  variation  of  the  personal  errors  never  will  be  found. 

The  matter  is  certainly  of  importance.  If  we  suppose  that  an 
observer's  personal  error  is  not  subject  to  very  sudden  variations  (as 
we  have  seen  is  not  the  case  with  tolerably  experienced  observers), 
it  will  for  common  astronomical  observations  be  of  no  importance 
whatever,  how  large  his  error  is,  if  he  only  determines  the  correc- 
tion of  the  clock  himself.  But  the  case  becomes  quite  otherwise,  if 
his  error  is  different  for  stars  of  a  different  magnitude.  If  he,  for 
instance,  observes  a  zone  of  small  stars  of  8  to  9' 10  mag.,  and  uses 


*  Vierteljahreschrift  der  Astron.  Gesellschaft,  viii.,  pp.  48-66. 


618  Proceedinffs  of  the  Royal  Irish  Acadetny. 

a  dock-correction  deriycd  from  four  or  five  standaid  stars,  tHe  dif- 
ferent estimation  of  bright  and  faint  stars  will  cause  a  constant 
fault  of  all  the  right  ascensions  of  the  zone. 

In  order  to  explain  the  deviations  of  Nyr6n's  constant  of  pre- 
cession from  those  of  Bcssel  and  Struve,*  we  might  seek  the  origin 
of  the  undeniable  difference:  Schjellerup -Bessel -Weisse  =  -  0*096 
in  such  a  different  estimation  in  one  of  the  two  observers,  which 
would  be  more  likely  to  have  existed  in  Bessel's  case,  as  Schjellerup's 
right  ascensions  can  hardly  be  affected  with  any  large  constant  error, 
considering  their  excellent  agreement  with  those  of  the  Gottingen 
zones,  f  which  are  founded  on  the  same  standard  stars.  Before  leav- 
ing the  Copenhagen  Observatory,  I  tried  to  find  whether  the  above 
difference  could  be  explained  in  this  way.  From  the  original  obser- 
vations of  Schjellerup's  and  the  ''  Konigsberger  Beobachtungen,"  I 
wished  to  derive  differences  of  right  ascension  between  zone  stars  ap- 
pearing in  both  catalogues,  and  standard  stars,  which  the  two  observers 
would  have  had  in  common,  if  such  had  been  observed  together  on  one 
night  in  Konigsberg,  as  well  as  in  Copenhagen.  But  it  appeared 
soon  that  any  certain  and  reliable  result  could  not  be  obtained  in  this 
way,  as  8chjellcrup  nearly  always  had  used  other  standard  stars  (one 
or  two  classes  fainter)  than  Bessel,  so  that  only  a  very  small  number 
of  zone  stars  occurring  in  both  catalogues,  could  be  compared  with 
one  and  the  same  standard  star.  However,  the  difference  between 
the  right  ascensions  of  the  two  catalogues  has  probably  another  and  a 
deeper  origin,  as  neither  of  the  two  constants  of  precession  used  now-a- 
days  seems  derived  in  quite  a  satisfactory  way.|  Besides,  according  to 
Argelander's  comparison  between  Bessel's  zones  and  Struve's  '*  Posi- 
tiones  mediee,''  it  does  not  seem  likely  that  the  former  are  affected 
with  any.  constant  error  as  the  one  suggested  above.  § 

It  cannot,  however,  be  doubted  that  a  different  estimation  of 
transits  of  bright  and  faint  stars  may  exist,  ||  and  an  example  has  been 
found  by  Argelander  by  comparing  Santini's  fifth  catalogue,  contain- 
ing positions  of  stars  between  90°  and  93°  N.  F.  D.,  from  observations 


*  Determination  du  coefficient  constant  de  la  precession  au  moyen  d*6toiles 
de  foible  6clat  Par  M.  Nyrdn  (Bulletin  de  I'Academie  Imp.  des  Sciences  de 
St.  P6t€rsbourg,  1869). 

t  Gottingen -Schjellerup  s~  0^-006  (E.  Copeland  nnd  C.  Borgen:  Mittlers 
Oerter  der  in  den  Zonen  -  Co  und  -  1®  enthaltenen  Sterne :  Gottingen,  1869 
(p.  13). 

X  Bessel  has,  for  instance,  nsed  Lindenau*8  constant  of  nutation,  which  is 
0"'26  too  small,  while  0.  StruTC  has  founded  his  researches  on  his  father's  deter- 
mination of  the  relation  between  the  mean  distances  of  stars  from  different  classes. 

§  Yierteljahrsschrift  der  Astron.  Gesellschaft,  vii.,  p.  17. 

I)  Bessel  has  already  suspected  this  (Briefwechsel  swischen  Gibers  und  Bessel,  ii., 
p.  358). 


Dreyer — On  Astronomical  Transit  Obset^ationa.       519 


1>7  Trettenero,  witH  the  catalogaes  of  Schjellerup  and  Bessel. 
found  by  dividing  the  stars  according  to  the  magnitude  :* — 


He 


Magn. 

Schj.-Tr. 

Stars. 

A'tt. 

6» 

+  0-023 

14 

-  O-'OIS 

7 

+  0  031 

36 

+  0  -017 

7-8 

+  0  -089 

23 

-  0  -022 

8 

+  0  -084 

68 

+  0  -002 

8-9 

+  0  -106 

74 

0  -000 

9 

4  0  -124 

120 

0  -000 

The  increase  of  the  difference  with  the  decrease  of  the  brightness 
of  the  stars  seems  beyond  doubt.  The  last  column  contains  the 
deviations  of  the  dLSerences  from  the  formula : — 

Schj.-Tr.  =  +  0-010  +  0-038  [Magn.  -  6«-0]. 

The  comparison  between  the  Padua  zones  and  those  of  Bessel  gave 
a  similar  result,  which,  however,  is  more  uncertain  than  the  above 
one,  owing  to  constant  errors  in  some  of  Bessel* s  zones,  uncertainty 
of  proper  motions,  &c.  Argelander  informs  us  also  that  the  third 
Padua  catalogue  has  been  found  by  himself  to  contain  a  similar  devia- 
tion of  the  faint  stars. 

It  seems,  therefore,  that  Trettenero  really  observed  faint  stara 
earlier  than  bright  ones,  probably  because  his  attention  while  observ- 
ing the  former  was  more  concentrated  in  the  work  of  the  eye,  or 
because  he  regularly  first  heard  the  beats  of  the  clock,  and  then 
saw,  while  he  observed  bright  stars  in  the  reverse  way.  Argelander 
has  already,  in  Vol.  VI.  of  the  Bonn  Observations  (p.  12),  suspected 
that  a  fault  in  his  own  R.  A.s  might  arise  in  this  way,  and  he  has 
later  examined  his  own.  observations  of  variable  stars,  in  order  to  find 
whether  any  certain  influence  of  the  magnitude  on  the  E.  A.  would 
appear  from  these.  The  result  was,  that  Argelander  seemed  to 
observe  stars  down  to  9*1  magnitude  in  the  same  way,  but  stars  of  the 
magnitude  9*2,  and  still  more  those  of  magnitude  9*3,  a  little  earlier ; 
but  that  the  error  for  the  latter  could  hardly  amount  to  more  than 
0*'15.  For  stars  below  the  9'3  magnitude,  the  accidental  errors 
seemed  to  amount  to  more  than  the  constant  one,  so  that  the  latter 
could  not  appear  distinctly.f 

As  observations  of  variable  stars  in  their  different  phases  of  bright- 
ness  are  included  in  the  programme  of  the  zone  observations,  at  present 
undertaken  by  different  observatories,  under  the  direction  of  the  Inter- 
national Astronomical  Association,  we  shall,  probably,  soon  possess 


*  Vierteljahnsclirift,  vii.,  p.  19. 


t  ABtron.  Nachrichten,  Ixxiy.,  p.  268. 


520  Proceedings  of  the  Bayal  Irish  Academy. 

a  number  of  trustworthy  results  respecting  the  personal  errors  of  faint 
stars. 

Closely  connected  with  the  question  of  personality  in  observations 
of  faint  stars  is  another  important  matter,  to  which  tiie  great  number 
of  nebular  observations,  made  during  the  last  twenty-five  years,  has 
turned  our  attention.  We  allude  to  the  constant  differences  between 
the  right  ascensions  found  by  different  astronomers.  It  is  especially 
Bchonfcld,  whose  results,  published  in  Vol.  I.  of  the  ''Mannheim  Ob- 
servations/' show  a  remarkable  deviation  from  those  of  all  other 
observers  of  nebulas,  as  the  following  equations  show : — 

Schonfeld  -  Laugier   =  -  0"-21. 
-d' Arrest  =«-0'38.» 

-  Schmidt  =  -  0-39. 
-Schultz    =-0-30.t 

-  Oppolzer  =  -  0*38.  t 

-  Yogel       =  -  0-21. 

Although  it  seemed  unquestionable  that  Schonfeld' s  right  ascensions 
are  too  small,  I  thought  it  would  be  of  interest  to  compare  them  with  the 
**  Micrometrical  Observations  of  500  nebulae  by  Dr.  Herman  Schultz," 
which  were  published  in  TJpsala,  in  1874,  in  order  to  see,  whether  the 
very  striking  difference  between  the  Mannheim  and  the  few  earlier 
TJpsala  observations  would  appear  again,  when  all  the  observations 
of  later  years  were  employed  in  the  comparison.  It  is  safest  only  to 
compare  objects  which  have  been  determined  by  both  observers  by 
means  of  the  same  comparison-star,  as  the  small  differences  between 
the  positions  of  the  different  star  catalogues  might  produce  here  too 
great  an  effect  upon  the  value  of  the  small  personal  equation.  Of 
tiie  163  objects  which  occur  both  in  Schultz' s  and  Schonf eld's  obser- 
vations, I,  therefore,  only  took  114,  which  have  been  compared  with 
the  same  star.  Of  these  114  the  neb.  h  393  could  not  be  used,  as  it 
seemed  most  probable  that  a  different  point  had  been  observed.  The 
remaining  113  equal  differences  nebula-star  gave  for  the  equation 
Schonfeld -Schultz 

Aa  cos  8  =  -  0--338. 

As  only  thirteen  nebulae  gave  a  very  small  positive  value  Aa  cos, 
there  is  no  doubt,  that  one  of  the  two  observers  has  a  different  way  of 
estimating  the  transits  of  stars  and  nebulas. 

That  these  indications  of  personal  equations  in  nebular  observations 


•  Mean  of  all  the  comparisoiu  contained  in  the  "  Observationes  Havnienses." 
ThU  number  is,  of  course,  of  less  value  than  the  others,  as  d' Arrest  only  observed 
most  nebulae  approzimatiyely.  The  comparison  between  Schonfeld  and  d* Arrest's 
"First  Series  (Leipzig,  1856)  gave  a  similar  difference,  which,  however,  disap- 
peared when  only  nebulse  observed  with  the  same  star  were  compared. 

t  Astron.  Naohr.,  Ixiii.,  No.  1504. 


Drsyer — On  Astronomical  Transit  Observations.       521 

do  not  depend  on  instrumental  circnmstances,  bnt  reallj  on  the 
observer's  individuality,  can  be  proved  in  several  ways.  Althongh 
8chonleld  observed  with  an  annular  micrometer,  whose  construction^ 
certainly,  tnay  give  rise  to  constant  errors,  it  is  impossible  in  this  way 
to  explain  the  differences  between  Schonf eld  and  the  other  observers 
of  nebulas.  Schmidt  observed  also  with  an  annular  micrometer,  and 
still  his  observations  differ  about  as  much  from  Schonfeld's,  as  those 
of  Schultz,  made  with  a  wire-micrometer.  Between  the  right  ascen« 
sions  obtained  with  nearly  equal  telescopes,  and  by  means  of  wire- 
micrometers  in  Leipzig  and  TJpsala,  I  found,  besides,  a  difference 
(Vogel- Schultz): 

Aa  cos  8  =  -  0-10,* 

which  agrees  very  well  with  the  difference  between  the  equations 
Schonf  eld- Schultz  and  Sch6nfeld-Yogel=  -0-34  -  (-0-21)--  0-13. 
But  the  second  series  of  Schonfeld's  observations,  published  only  a  few 
months  ago,  have  made  the  reality  of  the  influence  of  the  observer's  indi- 
viduality quite  unquestionable.  This  series  contains  153  objects,  which 
also  occur  in  Schidtz's  observations,  and  the  author  has  himself  com- 
pared their  B.  A.s  with  those  in  Schultz's  ''  Preliminary  Catalogue  of 
Nebulae,"!  which  is  less  troublesome  than  the  way  of  comparing  chosen 
by  me.     The  result  is  :  X 

Aa  cos  8  =  -  0-150, 
while  a  comparison  between  this  series  and  the  first  one  gave 
I.-II.«-0-2L 

These  two  comparisons  agree  most  perfectly  with  my  result  given 
above,  and  show  with  certainty  that  Schonf  eld,  being  aware  of  the 
fact  that  he  made  his  right  ascensions  too  small,  or  was  inclined  to 
observe  transits  of  nebulae  too  soon,  in  the  course  of  years  has  altered 
his  method  of  estimating  the  latter.  This  proves  to  some  extent  that 
the  personal  error  is  not  perfectly  independent  of  the  individual's  will, 
which  must  be  considered  as  one  of  ihe  most  important  results  we 
hitherto  have  found  respecting  this  abstruse  subject. 

My  examination  of  Schultz's  observations  has  given  another 
result,  which  also,  I  think,  is  of  some  importance.  Julius  Schmidt 
had  already,  by  comparing  his  own  observations  with  those  of 
£chonf eld,  found  the  equation  to  be  different  according  to  the  con- 


•  From  fifty-five  identical  differences :  nebnla  star.  I  have  already  mentioned 
this  equation,  as  well  as  the  preceding  one,  in  a  review  of  Dr.  Schultz's  work  in 
the  Yierteljahrsschrift  der  Astronomisdiien  Oesellschaft,  x.,  pp.  64-73. 

t  Monthly  Notices  of  the  R.  Astron.  Society,  xxxv.,  p.  136. 

X  AstronomiBcheBeohachtungen  auf  der  Stemwarte  zn  Mannheim,  ii.,  Carbruhe 
1876,  p.  8.  ' 


622 


Proc€eding%  of  the  Royal  Irish  Academy. 


densation  and  apparent  bubo  of  the  nebnlsB  (Astr.  Nachr.,  Nos.  146S 
and  1513),  BO  that  large  and  nncondensed  nebulflo  gave  the  greatest 
equation.  But  as  the  Athens  ohserrations  are  few  in  number,  this 
result  could  not  be  yery  reliable.  I,  therefore,  thought  it  of  interest 
to  see  whether  Schultz's  comprehensiTe  obserrationB  would  show  a 
similar  dependency,  when  compared  with  those  of  Schonfeld.  The 
result  of  my  examination  is  found  in  the  following  two  tables.  As 
might  be  expected,  the  condensation  of  a  nebula  has  more  influence 
upon  the  estimation  of  the  transits  than  its  size. 

Tasls  I. 
NeMcB  eloMtfied  acearding  to  their  apparent  Sifte, 


Clast. 

Diameter  of 
Nebul«. 

A«cot<. 

Namber  of 
NebubB. 

I. 

II. 

III. 

IV. 

0'-2-0'-6 
0  -6  - 1  -6 
1-6 -3-6 
3  -6  -  8  -6 

-0-28 
-0-36 
-0  -40 
-0-46 

67 
22 
20 
14 

Taslx  II. 
Nehula  ehusified  according  to  the  Degree  of  Condensation. 


CUm. 

Appearance. 

A«cot<. 

Number  of 
Nebuke. 

I. 

II. 

III. 

Planetary,  or  with  a 
starlike  nudeuB,     . 

Le38  condenied,  more 
irregular,     .     .     . 

Large  k  uncondensed, 

-0-16 

-0-39 
-0-44 

32 

63 
28 

We  have  now  come  to  the  end  of  our  researches  about  the* 
different  circumstances  under  which  personal  equations  and  errors 
appear,  and  shall  at  last  consider  the  probable  origin  of  the  pheno- 
mena. 

III. 

When  Bessel  had  first  remarked  the  considerable  equation  between 
himself  and  his  pupils,  in  the  winter  of  1 820,  he  tried  at  once  to  explain 
this  remarkable  phenomenon  from  the  co-operation  of  the  two  senses, 
sight  and  hearing,  which  takes  place  when  an  observation  is  made  by 


D&BTER — On  Astronomical  Tranrit  Observations.       523 

eye  and  ear.*  If  we  suppose  that  impressions  on  the  eye  and  ear 
cannot  be  compared  instantaneonsly  with  one  another,  and  that  two 
ohservers  take  an  unequal  time  to  transfer  the  one  impression  to  the 
other,  there  will  arise  a  personal  difference  or  equation,  which  will  be 
still  larger,  if  one  observer  begins  with  seeing  and  ends  by  hearing, 
and  the  other  observer  does  the  reverse. 

There  can  hardly  be  any  doubt  that  the  explanation  here  inti- 
mated, in  many  cases,  especially  when  the  equation  is  of  a  consider- 
able size,  is  the  right  one.  In  the  eye-and-ear  method  the  mind  is  in 
reality  at  work  in  three  different  ways :  hearing,  seeing,  and  count- 
ing the  seconds;  perhaps  one  might  say  in  four  ways,  considering  the 
expecting  of  the  coming  beats  of  the  clock.  The  longer  the  interval 
between  the  beats,  the  longer  time  this  expectation  will  of  course 
take  ;  and  this  is  perhaps  the  reason  why  Bessel's  personal  error  was 
found  half  a  second  smaller,  by  using  a  half-second  watch,  whose 
single  beats  were  counted,  so  that  he,  with  this  watch,  observed  0**494 
later  than  with  a  clock  beating  whole  seconds,  while  Struve  and 
Argelander  found  no  such  difference.!  However,  Bessel's  very  con- 
siderable error  cannot  be  explained  perfectly  in  this  way.  Encke  has 
tried  to  explain  it,  simply  by  supposing  that  Bessel  counted  a  second 
too  early,  and  this  certainly  agrees  with  the  decrease  of  the  error  by 
using  the  half -second  clock.  |  G.  Wolf  is  of  the  same  opinion,  §  and 
he  tells  us  that  a  few  years  ago  an  analogous  case  occurred  at  the 
Observatory  in  Paris,  where  an  observer  noted  all  the  transits  one 
second  later  than  all  the  others.  ||  But  although  this  proves  the 
possibility  of  such  a  mistake,  it  hardly  seems  probable  that  Bessel's 
personal  error  should  arise  from  such  a  very  simple  cause,  and  besides, 
how  should  we  explain  personal  equations  of  0*-5,,0**6,  0*-7,  of  which 
we  have  several  examples  in  the  eye-and-ear  method,^  and  how  can 
an  observer  continually  change  his  way  of  estimating  transits  in  the 
course  of  years  (in  which  case  we  could  not  think  of  a  new  way  of 
counting  the  seconds)  ?  We  have  already,  in  the  foregoing,  given 
several  examples  of  such  alterations,  and  the  equation  Bessel- Struve 
increased    besides,    continually,     until    it    reached    its    maximum 

•  Konigsberger  Beobachtungen,  vm.,p.  7. 

t  This  explanatioii  of  Bessers  error  has  already  been  suggested  by  Albrecht 
(Langendifferenzen,  &c.,  p.  36).  Several  obserrers  m  Leyden  observed  in  1861 
and  1862,  with  two  chronometers,  one  beating  single  seconds,  the  other  giving  130 
beats  in  one  minute ;  but  none  of  them  found  any  certain  variation  in  their  small 
errors,  caused  by  the  use  of  the  latter  (Yerslagen,  &c.,  zv.,  pp.  212  and  217). 

I  Monatsberichte  der  Berliner  Academie,  1858,  p.  617. 

f  Annales  de  TObservatoire  de  Paris,  M6moires,  t.  viii.,  p.  186. 

II  According  to  Radau  (Sur  les  erreurs  personelles,  p.  29,  Moniteur  Scientifique, 
1866),  tiie  said  observer,  to  his  great  surprise,  was  convinced  of  his  misteke 
by  observing  the  disappearance  of  an  artificial  star  behind  a  screen,  and  counting 
the  seconds  aloud,  while  another  person  (in  the  moment  of  the  disappearance)  gavo 
him  a  slap  on  the  back. 


IT  Nehus- Wolfers  =  +  0-73  (1833) 
Petersen  -  Madler  =+0-62  (1833) 
Gerling-Nicohd  «  +  0-78(l837) 
Dunldn  -  W.  Ellis -  + 0 -84  (1847) 


Main  -  Rogerson  =  +  0"-70  (1853). 
Jacob  -Sashoo  Jengar=+  0  -80  (1858). 
Quirling  -  Lucas  a  +  0  *67  (1868). 
Main  -  liuoas  8+0*70(1 868) ,  &c. 


B.  I.  A.  raOC.,  SBH.  II.,  VOL.  II.,  8CIB2fCB.  3  G 


624  Proceedings  of  the  Bayal  Ifiih  Academy. 

value  in  1823.  Wolf  proves  IiIb  aaaertion  bj  the  fact,  that  the  equa- 
tion Besael- Argelander,  by  occultationB  of  itan,  was  fonnd  =  —  0**222, 
but  by  transita  »  -  1''222.  I  do  not  undentiand  this  argument,  as 
there  is  no  reason  why  Bessel  should  count  the  seconds  properly  while 
observing  occultations,  but  not  when  he  observed  transits. 

Notwithstanding  these  but  slightly  proved  objections  to  Bessel's 
explanation  of  his  great  error,  nobody  has  attempted  to  deny  the  great 
influence  of  the  "  superposition  "  of  the  two  senses  on  the  appearance 
of  the  personal  error.  Fa^e  has  tried  to  elucidate  the  matter  by  a 
companson.*  We  might  imagine,  he  says,  that  the  intellect  was  an 
eye  in  the  interior  of  the  brain,  observing  the  effects  which  the  im« 
pressions  of  the  senses  make  in  the  fibres  of  the  nerves.  If  impres- 
sions of  the  same  nature  are  made  in  the  same  point,  this  interior  eye 
can  easily  decide  whether  they  arc  simultaneous  or  not ;  but  if  it 
should  observe  different  perceptions,  by  fibres  extending  to  different 
portions  of  the  brain,  the  interior  eye  would  have  to  move  from  one 
portion  to  another,  the  time  spent  in  this  movement  would  not  be 
remarked,  and  perceptions  divided  by  a  real  interval  of  time  might 
therefore  erroneously  be  considered  as  simultaneous.  The  time  lost 
in  passing  from  one  perception  to  another  is  different  in  each  indivi- 
dual, and  in  this  way  personal  e<juations  may  arise.  This  is  only  a 
comparison,  but  a  very  good  and  instructive  one. 

We  cannot,  however,  be  satisfied  with  this,  but  we  must  examine 
the  question  more  closely  in  order  to  see  how  a  personal  error  can 
arise,  both  in  the  eye-and-ear  method,  and  in  the  chronographic  one. 
Let  us  begin  by  considering  the  different  effects  of  the  senses,  and  the 
time  spent  in  their  completion,  as  this  time  already  gives  the  possibi- 
lity of  a  personal  error.  There  are  three  processes  by  which  a  per- 
ception is  made :  an  impression  on  a  receptive  organ  (the  eye  or  the 
ear),  the  passing  on  of  this  impression  through  the  nerves  to  the 
brain,  and  at  last,  the  mind's  perception. 

It  is  quite  clear  that  there  must  be  some  time  lost  during  the  two 
first  processes,  and  this  is  besides  proved  in  different  ways.  The 
impression  on  the  receptive  organ  is  quite  material,  and  lasts  some 
.time ;  very  brilliant  objects  are,  for  instance,  visible  to  the  eye  a 
short  time  after  this  organ  has  been  closed.  That  the  passing  on  to 
the  brain  through  the  nerves  requires  time  may  be  seen  from  direct 
experiments.  Helmholtz  has,  for  instance,  found  the  velocity  of  the 
propagation  of  a  nervous  irritation  equal  to  about  thirty-four  metres 
in  a  second,!  so  that  the  time  lost  in  bringing  an  impression  to  the 
brain  is  often  quite  perceptible. 

In  like  manner,  a  certain  time  must  elapse  before  the  material 
irritation  causes  the  mind  to  be  aware  of  what  has  happened.  As  we 
do  not  know  at  all  how  the  perception  arises,  that  space  of  time  can- 
not be  determined,  but  its  existence  can  indirectly  be  felt  if  we  deter- 
mine the  velocity  of  the  sensation,  or  the  time  in  which  the  mind  can 
only  be  occupied  by  a  single  perception.     We  may  determine  this  by 

*  Comptes  rendiu,  t.  lix.,  p.  475.      t  Foggendorf 'a  Aunalen,  Bd.  Ixziz.,  p.  829. 


Drkyer — On  Astronomical  Transit  Observations.        525 

seeking  the  minimum  of  time  in  wliich  two  different  efforts  of  tHe 
mind  can  foUow  each  other.  We  could,  for  instance,  find  the  time 
which  elapses  between  the  observation  of  an  instantaneous  sound,  or 
of  a  glimpse  of  light,  or  the  touch  of  an  external  object,  and  the 
immediate  completing  of  a  galvanic  current  through  the  pressure 
of  a  key  by  the  hand.  Experiments  to  this  effect  have  been  made  by 
Hirsch,  Hankel,  and  others.  On  an  average  we  can  consider  the  velo- 
city of  the  perception  of  a  sound,  of  a  glimpse  of  light,  or  of  the  sense 
of  feeling  »  0**20.  This  number  contains  the  velocity  of  the  propa- 
gation  in  the  nerves,  and,  besides,  the  time  which  elapses  between  the 
arrival  of  the  nervous  irritation  from  the  brain  to  the  muscles  of  the 
fingers,  and  the  contraction  of  these.*  But  as  these  intervals  are  very 
small,  compared  with  the  above  numbers,  they  prove  with  certainty  that 
a  limited  time  is  necessaiyforthe  accomplishment  of  the  mental  process.f 

The  above-mentioned  experiments  show  that  the  velocity  of  the 
sensation  contributes  to  the  formation  of  a  personality  in  the  percep- 
tion of  a  phenomenon,  as  the  single  observers  did  not  find  exactly  the 
same  residts.  In  the  chronographic  method,  where  the  eye  and  the 
hand  work  together,  a  different  estimation  of  the  coincidence  of  the 
star  and  the  wire  can  be  joined  by  a  different  way  of  pressing  the 
key.  The  former  circumstance  seems  to  be  of  great  importance, 
especially  if  we  observe  bright  stars  vrith  instruments  of  small  aper- 
ture, wluch  often  do  not  give  sharply-defined  images  of  the  stars.  In 
the  eye-and-ear  method  the  different  velocity  of  perception  may  be 
joined  by  the  ** superposition''  of  the  two  active  senses,  as  well  as  by 
a  different  manner  of  estimating  the  beats  of  the  clock,  perhaps,  also, 
by  the  expectation  of  them ;  while  the  chronographic  method  only 
requires  the  action  of  two  of  the  senses,  the  eye-and-ear  method  takes 
in  reality  four  actions  of  the  mind.  One  might  conclude  from  this 
that  personal  errors  in  the  chronographic  method,  within  shorter 
intervals  of  time,  change  less  than  in  the  eye-and-ear  method,  and  that 
greater  variations  do  not  appear  as  suddenly  in  the  former  as  in  the 
latter,  in  which  greater  variations  may  be  expected  even  within 
shorter  intervals.  As  we  have  seen  in  the  foregoing  pages,  obser- 
vations have  in  part  confirmed  this  conclusion,  and  it  is  a  fact  that 
errors  of  such  an  extent  as  Bessel's,  and  some  of  the  observers, 
mentioned  in  the  note  of  page  523,  have  never  been  found  in  the 
chronographic  method,  which  certainly  proves  the  great  inflaence  the 
simultaneous  working  of  the  senses  and  the  expectation  of  the  beats 
of  the  lock  have  on  our  estimation  of  a  transit. 

A  general  theory  cannot  1>e  given  of  the  origin  of  the  personal 
error.  We  can  only  point  out  different  circumstances  which  contributo 
to  the  formation  of  a  personal  error,  and  there  can  be  no  doubt  that 

•  By  Helmholte  found  =  0»01. 

t  If  it  Lb  necessary  to  proye  more  fully  the  duration  of  an  impression  on  the 
senses,  we  need  ojAj  remember  that  glimpses  of  light  or  sounds  which  follow 
one  ano^er  with  diorter  interyals  than  about  0«'05,  cannot  be  perceired  as  separat^ 
phenomena. 

8  0  2 


526  Proceedings  of  the  Royal  Irish  Academy, 

the  cause  of  one  observer's  error  is  not  the  same  as  the  canse  of 
another  observer's.  "Wolf  tries,  in  the  paper  we  have  so  often  quoted, 
to  give  a  general  theory  of  the  personal  error,  which,  however,  does 
not  include  the  very  large  ones,  with  i^espect  to  which  he  contents 
himself  with  Bessel's  explanation,  simply  adding,  that  constant 
practice  may  diminish  them.  He  recounts  so  many  ingenious  ex- 
periments that  this  is  sufficient  reason  for  us  to  examine  his 
ideas  more  closely,  especially  as  several  of  his  experiments  show 
that  the  causes  we  have  mentioned  on  the  foregoing  pages  are 
certainly  not  the  only  ones  which  give  rise  to  the  personal  faults. 

"We  have  already  seen  that  Wolfs  error  in  the  commencement  was 
found  =  +  0**3,  and  that  it  was  afterwards  brought  down  by-and-bye 
to  0"-l,  at  which  value  it  remained  constant.  In  order  to  see  whether 
this  small  correction  arose  from  the  confusion  of  hearing  and  seeing  at 
the  same  time,  he  placed  before  the  telescope  a  Geissler's  tube,  which 
gives  a  glimpse  every  second,  and  in  this  manner  marked  the  time. 
One  evening  he  found  by  common  eye-and-ear  observation  of  eighty 
angle  transits,  the  error  =  +  O'-ll,  and  by  a  series  of  observations  with 
the  tube,  instead  of  the  clock  (intermixed  with  the  former)  the  error 
=  0*'10.  Another  time  the  seconds  were  marked  by  the  star  itself, 
which,  as  an  electric  spark,  blazed  up  every  second,  so  that  a  sudden 
flash  showed  the  position  of  the  star  in  the  field  at  the  beginning  of 
each  second.  By  stopping  his  ears,  in  order  to  avoid  hearing  the  noise 
of  the  spark,  the  error  was  found  =  +  0**08,  while  common  observa- 
tions at  the  same  time  gave  +  0'*10.  Accordingly,  "Wolfs  error  was 
always  constant,  whether  the  observation  was  made  by  sight  alone,  or 
with  the  assistance  of  the  ear.  However,  he  tried  in  another  way, 
whether  *'  le  temps  mort "  existed,  as  if  so,  its  duration  would  depend 
on  which  organ  was  used.  He  substituted  feeling  for  hearing  by 
receiving  light  electric  shocks  in  the  left  hand  with  a  second's  interval. 
Eighty  transits  of  this  kind  gave  his  correction  =  +  0*-ll  exactly  the 
same  as  common  observations.* 

Having  convinced  himself  that  the  simultaneous  working  of  two 
senses  could  not  give  rise  to  his  personal  error,  as  it  remained  the 
same,  whether  one  sense  was  working  or  the  sight  and  the  feeling 
co-operating,  instead  of  the  sight  and  hearing.  Wolf  produced  by 
means  of  holes  in  a  moveable  board  three  artificial  stars,  situated  one 
above  the  other,  in  a  line  perpendicular  to  the  direction  of  their 
motion.  The  central  star  was  always  visible,  the  upper  and  lower 
one  at  the  same  time,  but  only  for  an  instant,  for  example,  regularly 
with  a  second's  interval.  There  appeared,  then,  a  remarkable  circum- 
stance, that  at  the  moment  the  two  outer  stars  flashed  up  the  observer 
imagined  he  saw  the  central  one  had  moved  a  little  in  advance  of  the 
other  two,  and  this  advance  seemed  proportional  with  the  velocity. 
However,  the  foremost  star  always  seemed  to  be  furnished  with  a  ray 
of  light  behind  (renching  to  the  spot  it  should  have  occupied  between 

*  Annales  de  rObservatoire  dc  Paris,  viii.,  p.  189. 


Dretbr — On  Astronomical  Transit  Ohservatiom,        627 

the  other  two)  when  the  outer  ones  appeared  with  regular  intervals ; 
4uid  it  was  only  sharply  defined,  if  these  latter  flashed  up  at  irregular 
intervals.  But  if  the  steadily  shining  star  had  been  caused  to  dis- 
appear at  the  moment  when  the  others  appeared,  they  were  all  seen 
in  a  straight  line. 

Wolf  explains  these  phenomena  in  the  right  way,  I  think,  when 
he  says,  that  by  the  irregular  sudden  appearance  of  the  outer  stars, 
the  eye,  taken  by  surprise,  is  principally  occupied  with  them  for  a 
moment,  and  in  the  meantime  ceases  to  observe  the  central  one,  which 
•can  only  be  seen  again  after  that  moment,  at  a  time  when  it  has 
moved  in  advance.  This  last  impression  seems  now  to  the  mind  to  be 
simultaneous  with  the  sudden  appearance  of  the  other  two  stars. 
J5ut  if  they  appear  at  regular  intervals,  the  mind  is  prepared  for  their 
appearance,  and  the  observation  of  the  motion  of  the  steadily  luminous 
star  is  not  perfectly  interrupted  during  the  sudden  impression.  While 
this  lasts,  the  observer  will  therefore  see  all  the  places  which  the  star 
has  occupied,  and  it  depends  now  entirely  on  his  individuality  as  to 
which  place  he  will  select  out  of  this  series,  and  consider  simultaneous 
with  the  sudden  appearance  of  the  outer  stars.  To  conclude,  &om 
the  sign  of  Wolf's  personal  error,  he  selected  the  place  which  ^as 
reached  by  the  central  star  at  the  end  of  the  sudden  impression.  But 
when  the  eye  begins  to  see  the  flashing  sparks,  it  retains  all  the  posi- 
tions which  the  central  star  successively  occupied  during  a  space  of 
time  equal  to  the  duration  of  a  luminous  impression ;  it  is,  therefore, 
also  possible  that  an  observer  imputes  the  position  of  the  star  in  the 
moment  of  the  flashing  up  to  some  point  in  this  '^parcours  anterieur.'* 
Lastly,  if  we  abolish  the  steady  illumination  of  the  central  star,  it  is 
not  possible  to  see  a  series  of  its  positions  during  the  sudden  impres- 
49ion,  and  the  personal  error  is  done  away  with,  at  least  for  an  antici- 
pating observer.* 

Such  impressions  on  the  senses,  which,  to  the  mind,  seem  to  last  for 
49ome  little  time  (although  their  duration  in  reality  is  extremely  short), 
must,  according  to  the  above,  be  of  great  imj^ortance  as  the  sources  of 
personal  errors.  Wolf  tries  on  these  experiments  to  found  a  theory 
for  all  kinds  of  personal  equations  in  transit-observations,  without 
being  quite  successful,  as  far  as  we  can  see.  He  remarks  that  the 
above  explanation  of  personal  errors,  in  case  of  our  perceiving  the 
seconds  by  the  eye,  cannot  without  alteration  be  applied  to  the  eye- 
and-ear  method,  as  a  considerable  difference  between  the  duration  of 
perceptions  by  the  eye  and  by  the  ear  has  been  found  by  his  own 
direct  researches,  as  well  as  by  those  of  Helmholtz  and  Emsmann. 
If  we  perceive  the  seconds  by  the  ear,  the  impression  will  certainly 
last  for  an  extremely  short  time  (less  than  O'Ol),  but  owing  to  the 

*  Hartmann  has  found  Boxnething  similar  by  his  apparatus  (6runert*8  Archiv. 
fiir  Mathematik,  xxxi.,  p.  17).  If  he  placed  a  scale  in  the  telescope  and  before  the 
•observation  remarked  at  which  division  the  star  should  be  at  the  second-beat,  he 
often  fancied  when  he  concentrated  his  attention  on  the  motion  of  the  star,  that  he 
«aw  it  a  little  in  advance  of  its  real  position.  He  oftener  saw  it  in  the  right  place 
when  he  was  tired. 


fi28  Proceedings  of  the  Royal  Irish  Aeadenty. 

duration  of  the  InminouB  impressioii,  we  will,  during  this  abort  time, 
aee  the  star,  not  only  in  its  real  place,  but  also  in  all  the  places  it 
baa  occupied  during  an  interral  equal  to  the  duration  of  the  luminous 
impression. 

It  does  not  seem  possible  that  there  can  be  any  objection  to  this ; 
but  in  order  to  account  for  those  errors  by  which  the  position  of  the 
star  is  anticipated,  Wolf  supposes  that  the  transient  impression  from 
the  place  which  the  star  really  occupies  in  the  moment  of  the  second- 
beat,  also  may  allow  the  mind  to  impute  the  following  positions  which 
the  star  occupies  during  this,  to  the  instantaneous  audible  second-beat 
as  simultaneous  with  it.  This  last  supposition  seems  a  litUe  difficult 
to  understand. 

As  we,  therefore,  cannot  fully  adopt  Wolfs  theory,  we  must  be 
content  to  consider  the  question  about  the  origin  of  the  personal 
errors,  as  elucidated  in  dinerent  ways  by  the  foregoing.  In  order  to 
give  a  short  review  of  what  we  have  already  said,  we  may  mention 
among  the  principal  causes  producing  personal  errors :  the  co-opera- 
tion of  the  different  senses;  the  expectation  of  the  regularly  returning 
beats  of  the  clock ;  the  different  velocity  of  the  sensation ;  and  lastly, 
the  difference  of  habit  in  the  mechanical  actions. 


App£iinix. 

Since  the  above  paper  was  read  before  the  Boyal  Irish  Academy, 
Professor  Bakhuyzen  kindly  sent  me  some  results  of  observations  made 
by  himself  and  the  assistants  at  the  Leyden  Observatory,  which  con- 
firm several  conclusions  arrived  at  in  the  foregoing  pages.  It  deserves, 
for  instance,  our  attention  that  observations  of  Polaris  by  day  and  by 
night  have  again  shown  the  considerable  influence  which  an  eccentric 
illumination  of  the  wires  can  exercise  over  the  personal  error.  That 
this  is  the  only  circumstance  through  which  it  is  possible  to  account 
for  the  anomalies  which  so  often  have  appeared  in  observations  with  a 
**  broken  telescope,"  has  anew  been  proved  by  Dr.  Valentiner's  and 
Dr.  Becker's  observations  with  the  time-collimator,  as  the  different 
direction  of  the  motion  of  the  star  was  found  to  have  very  little  or  no 
influence  on  the  personal  error. 

Observations  have  been  made  in  Leyden  in  order  to  try  whether 
the  observers  estimated  the  transits  of  bright  and  faint  stars  differ- 
ently. The  observations  which  were  taken  with  the  meridian-circle 
and  chronograph  gave  the  following  results : 

Start3-6magii.  Star*  8  - 9  magn.      ^JJ^^. 

Valentinep  -  Becker  =  -  0«-30  (12  stars},  -  0-21  (16  stare),     -  0-09.       . 

Valentiner-  H.  G.  Bakhuyzen  =  +  0  -13  (34  stars),  +  0  -18  (63  stare),     -  0  -06. 
Valentiner  -  E.  F.  Bakhuyzea  =  -  0  -16  -0-17  +0  -01. 

The  difference  in  the  equation  Yalentiner- Becker  for  bright  and 
for  faint  stars  has  been  coiidGlrmed  by  the  zone-observations  of  stara 
between  30^  and  35°  northern  declination  made  in  Leyden. 


Habdmak — On  Analysts  of  Coab  and  Iron-stones.      529 


XLT  . — ^Analysis  of  Coals  Ain>  lEoir-9Toirss  fbom  the  DmroAirKosr 
CoAL-FixLD,  Co.  Traoins.  By  Edwabd  T.  Habdman,  P.C.S., 
&c.y  of  the  Geological  Survey  of  Ireland. 

[Bead  February  28ih,  1876.] 

AiTALTsxs  of  one  or  two  of  the  coals  of  Dungannon  haye  been 
already  published  by  Sir  Richard  Griffith,*  and  Sir  Robert  Kane.f 

During  a  stay  of  over  a  year  in  the  neighbourhood,  while  making 
a  surrey  of  the  coal-field,  I  had  opportunities  of  obtaining  good 
average  samples  of  all  the  more  important  coals  at  present  being 
worked,  and  having  examined  them,  I  now  propose  to  place  the  re- 
sults before  the  Academy. 

I  have  already,  elsewhere,  published  more  or  less  detailed  descriptions 
of  this  coal-field,^  and  shall  enter  no  further  at  present  into  what  would 
only  be  repetition  than  to  say  that  the  coal  measures  there,  although 
occupying  but  a  small  area,  are  about  2,000  ft.  thick,  and  contain  from 
22  to  24  coal  seams;  all  of  them  of  fair,  and  some  of  excellent  quality. 
These  vary  in  thickness  from  10  in.  to  9  ft. 

Appended  is  a  list  of  the  more  important  of  these  coals  in  order : 

Table  of  the  Coals  at  PnEssirr  bedto  Woeeed. 

Dungannon   CotU-Field, 

ft.  in. 

^Annagher  Coal,t 9       0 

Middle         Bone  Coal, 2  10 

Coal  Shining  Seam, 3      0 

Measures.    .  Brackaville  Coal, 5      0 

I  GortnaskeaCoal(with22in.cannel),J  6       0 

{Coal  Island     Beltiboy  Coal,J 3       0 

s&riei).  Hqttj  Coal,J 3       6  to  5  ft. 

L  Yard  Coal, 3      0 

iSeSi.    jCreenaghCoalt(withl4in.cannel),t   4      6 

Lower  Coal  \ 
Measures,     f  Main  Coal  of  Drumglass,}       .     .     .     4     10  to  6  ft. 
{Drumglass    I  Lower  „  „  ...     1       6  to  2  ft. 

series),       ) 

Those  marked  with  an  asterisk  are  included  in  the  following  ana- 
lyses, being  the  only  seams  which  were  worked  upon  when  I  was  in 
IJie  district. 

*  Oeological  and  Mining  Surveya  of  Tyrone,  ftc.  (Dublin,  1839),  p.  12.  These 
analyaes  are  nnf  ortiinately  nearly  uBelesa  by  reason  of  misprints. 

t  Industrial  Resources  of  Ireland. 

1  See  "  On  the  Present  State  of  Coal  Mining  in  the  Co.  Tyrone."  By  Edward 
T.  HaTdmaTi,  in  Jour.  Roy.  Dub.  Soc.,  Vol.  vi..  part  42,  p.  366.  Also  **  Oeolo- 
gical Structure  of  the  Tyrone  Coal-fields."    Report  Brit.  Assoc.,  1874,  Belfast. 


530  Praeeedingt  of  the  Royal  IrUk  Academy. 

By  the  kind  pennisrion  of  Professor  Oalloway,  the  analyses  were 
for  the  most  put  performed  in  the  very  complete  laboratory  under 
his  control  at  the  Eoyal  College  of  Science,  Dublin. 

Air ALT8B8  OF  TEX   CoALS   OF  THB  DUVGAKKOIT    CoiX-FlELD. 
LOWEE  COAL-KSASUBES. 

No.  1. — Main  Coal  or  Lrumghm  Coal,    Lurgaboy  (Top). 
Akajltsis. 

Tolatile  matter  (including  sulphur  and  water),      48*00 

^  ,       (  Fixed  carbon, 47*43 

^^^^    (Ash, 4*57 

10000 
Water  at  21 2°  F.,    .     2*49  per  cent. 
Sulphur,  ....     2*80       „ 
Ash  in  coke,       .     .     9*05       „ 
Specific  Gravity,     .     1*295 

Heatino  Powek. — 1  lb.  of  the  coal  evaporates  12*86  lbs.  of  water 
&t  212°  F.;  and  1  cubic  ft.  of  the  coal  evaporates  1109*68  lbs.  of  water 
at  212^  F. 

The  above  forms  the  uppermost  portion  of  the  main  seam.  It  is 
an  extremely  good  coal,  not  yielding  in  quality  to  the  best  English 
specimens.  Although  somewhat  hard,  and  occasionally  difficult  to 
londle,  it  bums  with  a  very  brilliant  flame,  abounding,  as  it  does,  in 
gas-forming  materials.  The  ash  is  small  in  quantity,  and  light  coloured. 
The  heating  power  is  very  high.  This  portion  of  the  seam  varies  in 
thickness  &om  1'4"  in  Lurgaboy,  to  I'lO"  in  Drumglass,  and  nearly 
3'  in  Congo,  and  is  separated  by  a  band  of  black  shale  or  fire-clay 
called  "  clearing, ^^  which  is  three  feet  thick  in  Lurgaboy* — ^from  the 
bottom  coal. 

No.  2. — Main  Coal,     Lurgaboy  (Bottom). 

AvALTsrs. 

Tolatile  matter,  including  sulphur  and  water,  .  37*19 

tny^      (  Fixed  carbon, 51*53 

t^^^®      Ufih, 11-28 


10000 
tWater  at  212°  F., .     5*72  per  cent. 
Sulphur,    ....     1*65       „ 
Ash  in  coke,  .     .     .  17*95       „ 
Specific  gravity,       .     1*385 

*  Towards  the  west  of  the  Goal-field  the  "  clearing  "  diminishea  to  a  couple  of 
Liyen,  a  few  inches  thick  only, 
t  Mean  of  two  ezpeximents. 


Hardman — On  Analysis  of  Coah  and  Iron-stones.      531 

HEATiKa  Power  : — 1  lb.  of  the  coal  evaporates  12*  15  lbs.  of  water 
at  212°  F.;  and  1  cubic  foot  of  the  coal  evaporates  1043*32  lbs.  of 
water  at  212*^  F. 

This  portion  of  the  coal  is  of  rather  inferior  quality,  as  it  contains 
layers  of  shale  or  slate,  sulphate  of  lime,  &c.  The  ash  is  large  in 
quantity,  and  of  a  heavy,  dirty,  red  appearance.  The  heating  power  is, 
however,  high,  and  it  is  on  the  whole  a  good  strong  coal,  very  useful 
for  furnaces,  &c. 

The  next  coal  of  value  above  this  is  the  Creenagh  eoal^  which  is 
made  up  of  several  portions,  the  section  being  : — 

ft  in. 

Upper  "  soft  coal,"  ...     1  10 

Cannel  coal, 1  2 

Cracker, 0  4 

Lower,  "  soft  coal,"      .     .     1  2 


6 


1^0.  3. — Creenagh  soft  coal.    From  Castlestuart  Colliery,  Creenagh. 

Analysis. 

Volatile  matter,  including  sulphur  and  water,   .     43*40 

^  ,         (  Fixed  carbon, 39*80 

^^^®'     ( Ash,* 16*80 

100*00 
Water  at  212°  F.,     .     7*46  per  cent. 
Sulphur,    ....     1*94       „  • 
Ash  in  coke,  .     .     .  21*30       „ 
Specific  gravity,       .     1*462 

HJsATDre  Power. — 1  lb.  of  the  coal  evaporates  10*45  lbs.  of  water 
at  212°  F.;  and  1  cubic  foot  of  the  coal  evaporates  930*75  lbs.  of  water 
at  212°  F. 

The  Creenagh  soft  coal  is  rather  tender,  but  is  sometimes  obtained 
in  large  blocks.  It  is,  however,  very  ashy,  and  contains  many  layers 
of  sulphate  of  lime,  which  both  add  to  its  weight  and  deteriorate  the 
quality.  The  ash  is  heavy  and  dirty,  and  the  heating  power  is  lowest 
of  any  seam  in  the  district.  It  is  at  the  same  time  a  useful  coal,  and 
in  good  demand  in  the  neighbourhood. 

It  may  be  mentioned  that  the  pit  from  which  the  specimens  used 
in  the  above  analysis  were  obtained  was  very  wet,  owing  to  the 
encroachment  of  water  through  a  fault.  This  will  probably  account 
for  the  extreme  amount  of  hygroscopic  moisture  estimated. 

*  Mean  of  four  experiments. 


632  Proceedings  of  the  Royal  Irish  Academy. 

Vo.  4.-^Creetuigh  Cannel  Coal.    Prom  Castlestuart  Colliery,  Creenaglu 

AlTALTSIS. 

Yolatile  matter,  including  sulphur  and  water,  .     52*87 

^  ,  ^      (  Fixed  carbon, 34-18 

^''^•'     (Ash, 12-95 

100-00 
Water  at  212°  F,     .    3-20  per  cent. 
Sulphur,   ....     1-94       „ 
Ash  in  coke,  .     .     .  3002       „ 
Specific  gravity,       .     1*396 

Heatikg  Powkr: — lib.  of  the  coal  evaporates  12'371b8.  of  water  at 
212°  F.;  and  1  cubic  foot  of  the  coal  evaporates  1070-64lb8.  of  water 
at  212°  F. 

This  coal  is  an  extremely  valuable  band,  and  although  thin,  has 
been  worked  very  profitably,  fetching  large  prioes.  In  quality 
and  yield  of  gas,  it  is  considered  much  superior  to  Wigan  cannel,  and 
equfll  to  the  best  Lesmahago  coal.  Appended  is  part  of  a  report 
written  for  Messrs.  Young,  formerly  owners  of  the  colliery.  Castle- 
stuart,  Creenagh,  by  Dr.  Wallace,  Gas  Examiner  to  the  City  of 
Glasgow,  whose  determination  of  the  proximate  analyses  closely 
resembles  my  own  (see  note  below).* 

Middle  Coal-Measubes. 

Ko.  5. — Derry  Coal.    From  Mr.  King's  Pit,  Annagher,  Coal-Island. 

Analysis. 

Yolatile  matter,  including  sulphur  and  water,   .  26*43 

±  n  V,        (  Fixed  carbon, 55-57 

t^^^^'     (Ash, 18-00 

10000 
Water  at  212°  F.,      Not  estimated. 
Sulphur,       ...  „ 

Ash  in  coke,      .     .     24*65  per  cent. 
Specific  gravity,     .       1*499 

•  Analtbis  op  Crbexaoh  Canwbl. — Bt  Dr.  Wallacb. 
Volatile  matter  containing  0*76  Biilphur,     .    47*68 

(Fixed  carbon,  .     .    33-49  \ 
Sulphur,      ...      112  }.    .    49*26  carbon  in  ooke,  68  percent* 
AbH, 14-65  ) 

Water  at  212»  F., 3-06 

10000 

Oas  per  ton  at  60«  F.,  and  30"  Bar., 11*600  cubic  feet. 

Illuminating  power  in  standard  sperm  candles,      .     .    34*09 
Br.  Wallace  considers  it  could  be  made  to  yield  eren  as  much  as  14*000  cubic  feet 
per  ton. 

t  Mean  of  two  experiments. 


Hakoman — On  AnalyM  of  Coab  and  Iron-stones.      533 

HEATnra  Powxb.-*1  lb.  of  the  coal  evaporates  12-65  lbs.  of  water 
at  212^  F.y  and  1  cubic  foot  of  coal  evaporates  1125-06  lbs.  of  water  at 
212°  F. 

This  coal  is  now  only  worked  in  two  pits  in  the  townland  of 
Annagher,  where  both  in  quality  and  thickness  the  seam  has  greatly 
deteriorated,  according  to  the  reports  of  those  who  have  been  engaged 
working  it.  The  specimens  obtained  were  of  very  poor  appearance, 
being  dull,  slatey,  and  lumpy,  and  composed  of  thm  bands  of  coal 
alternating  with  layers  of  shale  and  sulphate  of  lime.  The  seam  is  3' 
to  3'6"  thick.  Only  a  partial  analysis  has  been  yet  made.  The  ash 
is  plentiful,  and  of  a  dirty,  red  colour,  and  the  cosJ  contains  much  iron 
pyrites  (sulphide  of  iron). 

It  is  remarkable  that  this  coal  has  such  a  high  heating  power, 
considering  the  very  lai^e  amount  of  ash  it  contains.  But  as  much  of 
the  ash  consists  of  iron  oxide,  resulting  from  the  ignition  of  the  iron 
pyrites,  so  abundant  in  the  coal,  some  of  the  heat  is,  no  doubt,  due  to 
the  combustion  of  the  sulphur  in  the  pyrites. 

1^0.  6. — Beltiboy  Coal,     From  Mr.  Slone's  pit,  Gortnaskea. 

Analysis. 

Tolatile  matter,  including  sulphur  and  water,   .     49*40 

ri  X.        (  Fixed  carbon, 48*17 

^^^®'     (Ash, 2*43* 

10000 
Water  at  212°  F.,    .     4*30  per  cent. 
Sulphur,  .     .      .     .     1*52       „ 
Ash  in  coke,       .     .     4*86       „ 
Specific  gravity,      .     1*266 

Heating  Powkr. — lib.  of  the  coal  evaporates  12*82 lbs.  of  water 
at  212°  F.;  and  1  cubic  foot  of  the  coal  evaporates  1006*25  lbs.  of  water 
at  212°  F. 

This  is  the  next  workable  coal  above  the  Derry  coal,  but  between 
them,  in  50  yards  or  so,  there  are  4  or  5  thin  coals  of  very  good 
quality  which  have  been  occasionally  wrought  at  the  outcrop.  The 
Beltiboy  coal  is  about  a  yard  thick,  or  3'6"  sometimes,  and  like  most 
coal  seams,  consists  of  several  bands  of  various  quality  \  some  parts 
have  even  been  used  for  gas. 

No.  7. — Gortnaskea  Coal, 

Above  this  coal  comes  the  €k>rtnaskea  seam,  a  coal  6  feet  thick, 
including  22  inches  of  cannel  at  the  top.  I  have  only  been  able  as 
yet  to  make  a  partial  analysis  of  the  cannel.    In  appearance,  however, 


•  Two  exi>eiiment8. 


634  Praeeedmga  of  the  Boyal  Irish  Academy. 

this  is  an  extremely  fine  coal,  quite  equal,  if  not  even  superior,  to  tiie 
Creenagh  cannel. 

Ash, 4*06  per  cent. 

Specific  gravity, .     .     1-232 

It  is  rare  to  find  a  cannel  coal  with  such  a  small  percentage  of  ash. 

Next  in  succession  comes  the  Brackaville  coal,  the  Shining  seam, 
and  the  Bone  coal.*  Those  I  could  not  ohtain  specimens  of,  as  the  two 
former  were  not  heing  worked  when  I  was  in  the  distiict ;  the  last 
coal  I  saw  in  a  new  pit,  on  old  workings,  and  it  may  give  some  idea  of 
the  expensive  style  of  mining  there  when  I  mention  that  a  fortnight 
after  Uie  pit-men  opened  it,  it  was  found  untenable  on  account  of  the 
water  from  the  old  workings,  and  other  causes.  As  I  had  deferred 
collecting  specimens  until  the  solid  coal  should  be  reached,  I  was  dis- 
appointed in  obtaining  an^.     The  seam  is  2'6"  to  3'  thick. 

A  few  yards  aboye  this  lies  the  Annagher  coal.  This  seam  is  in 
most  places  9  feet  thick,  and  is  an  extremely  fine  bed ;  a  soft,  rich, 
black  coal,  full  of  gas,  containing  a  mere  trifle  of  ash,  and  but  little 
sulphur.  It  is  very  difficult  to  work  on  account  of  its  having  a  very 
thick  bed  of  soft  fire-clay  for  a  seat.  This  often  swells  up,  and  makes 
the  levels  quite  impassable. 

The  samples  from  which  the  analyses  were  made  were  obtained  at  a 
small  *'  Gin  Pit,"  sunk  on  the  outcrop  of  the  coal  in  Annagher.  The 
pit  was  only  1 4  yards  deep,  and  mostly  in  drift. 

No.  8  . — Annagher  Coal,     From  a  small  pit  in  Brackaville. 
Analysis. 

Tolatile  matter,  including  sulphur  and  water,  .     45*62 

p  ,         (  Fixed  carbon 62-46 

^""^^^     (Ash, 1-92 


100-00 
Water  at  212°  F.,      9-89  f  per  cent. 
Sulphur,      .     .     .     2-56         „ 
Ash  in  coke,     .     .     3*55 
Specific  gravity,    .     1250 

Heatiwo  Powkk  : — 1  lb.  of  the  coal  evaporates  12-48  lbs.  of  water 
at  212°  F.;  and  one  cubic  foot  of  the  coal  evaporates  967*20  lbs.  of 
water  at  212°  F. 

The  above  analyses  will  give  a  very  fair  idea  of  the  character  of  the 
coals  in  the  Dungannon  Coal  Field;  and  it  will  be  seen  that 
many  of  these  will    bear    favourable    comparison    with    the   best 

*  Could  this  name  be  merely  the  French  Bon  f  It  is  not  improbable  tiiat  the 
name  may  baye  been  applied  by  Ducart,  an  Italian  engineer,  who  worked  thesQ 
mines  100  yean  ago,  especially  as  it  m  a  coal  of  superior  quality. 


Hardman — On  Analysis  of  CoaJs  and  Iron-stones.       635 

English  coal  in  point  of  purity  and  heating  power.  They  are  all 
highly  bituminous,  and  yield  such  a  quantity  of  gaseous  matter  that 
any  of  them,  except  the  Deny  coal,  might  be  used  with  great  advan- 
tage in  Ireland  for  gas  manufacture,  with  profit,  both  to  the  colliery 
owner  and  to  the  gas  company :  a  point  which  ought  to  be  thought 
of  if,  as  I  hope,  these  coals  some  day  come  to  be  properly  and  exten- 
sively mined. 

The  heating  power  is  extremely  high ;  10  to  11  lbs.  of  water  eva- 
porated is  considered  very  good  work  for  1  lb.  of  coal;  nearly  all  these 
give  over  12,  the  best  of  them  very  nearly  13  lbs.  The  heating  power 
was  determined  directly  by  Thompson's  very  elegant  and  simple  appa- 
ratus. This  is  both  more  exact  than  the  methods  of  calculation  from 
the  ultimate  composition,  or  by  actual  experiments  with  a  furnace 
and  boiler,  and  infinitely  more  convenient  than  the  latter  process. 

The  analyses  show  that  several  of  these  coals  contain  an  excessive 
amount  of  water,  e,  ^.,  the  Creenagh,  Annagher,  and  Bottom  Lurgaboy 
coals.  This,  however,  is,  I  think,  entirely  due  to  the  state  of  the  pits  ; 
the  specimens  from  the  two  former  seams  being  obtained  from  pits  lite- 
rally swimming  in  water,  which  were  either  surrounded  with  old  work- 
ings, or  only  on  the  very  outcrop  of  the  coal.  It  is  not  unlikely  that 
under  more  favourable  conditions  this  item  would  be  much  diminished  ; 
and  it  must  be  remembered  also,  that  none  of  the  pits  at  present 
being  worked  on  the  coals  enumerated  herein  are  sunk  on  tie  best 
portions  of  the  seams,  or  under  anything  like  favourable  arrangements. 

One  thing  worth  noticing  in  these  coals  is  the  complete  proportion 
between  their  specific  gravity  and  the  amount  of  ash  they  contain. 
It  has  been  a  subject  of  no  little  discussion  as  to  whether  there  is  any 
relation  between  the  amount  of  ash  and  the  specific  gravity,  and  I 
find  it  stated  in  Knapp's  Technicology  ♦  that  no  direct  connection  can 
be  deduced.  However,  Professor  Johnson,  a  well-known  American 
geologist  and  chemist,  is  referred  to  as  believing  ''  such  to  bo  the  case 
with  coal  from  the  same  coal-field,  and  considers  the  specific  gravity 
to  be  an  index  of  the  purity  of  the  coal.  In  analysing  anthracites 
from  Beaver  Creek,  Luzerne  County  (Pennsylvania),  he  found  in  four 
varieties  the  following  relative  quantity  of  ash : — 

fBEAVEB  Creek,  Pennstlvaiha. 


Specific  Gravity. 

Ash  per  cent. 

1 

2 
3 
4 

1-660 
1-694 
1-613 
1-630 

1-28 
4-00 
601 
6063 

*  Knapp's  Chemical  Teclmicologv.      Drs.  Bonald*s  and  Kichardson,  vol.  1, 
pt.  1,  n.  47-8  a866). 

t  It  must  DO  remembered  that  the  specific  gravity  of  anthracite  is  always 


higher  than  that  of  bituminous  coal. 


536 


Proceeding9  of  the  Royal  IrUh  Academy. 


In  the  coal  from  the  basin  of  Maiyland,  bordering  on  TeaikajbnadM^ 
a  similar  result  was  obtained.     The  coals  are  bitmninous. 


Mean  Sp.  Gravity. 
Two  Specimens. 

Mean  anoost  Ash 
Two  Specimens. 

1 

2 
3 

4 
6 

1*320 
1-360 
1-360 
1-385 
1-486 

7-62 

9-68 

10-36 

11-75 

14-41 

My  analyseB  show  a  very  close  agreement  in  this  respect  with  some 
of  the  Maryland  coals,  as  will  be  seen  from  the  following  Table : — 


DxrVGAlTKOK  CoAL-FnCT.D. 

Specific  Gravity. 

Amovntof  Ash. 

1 

2 
3 
4 
6 
6 
7 
8 

Annagber  coal,   .    .    . 
Beltiboy      „       .     .     . 
Oortnaflkea  coal,  cannel, 
Lnrgaboy  top  cool,  .    . 
Do.           bottom  coal, . 
Creenagh  coal,  cannel, 
Do.           soft  coal, .    . 
Deny  coal,     .... 

1-260 
1-266 
1-232 
1-296 
1-386 
1-386 
1-452 
1-499 

1-92 

2-43 

4-06 

4-67 

11-28 

12-96 

16-80 

18-00 

With  the  exception  of  the  Gortnaskea  cannel,  which  slightly 
breaks  the  series,  this  increase  of  ash  with  that  of  the  specific  gravity 
is  extremely  well  marked  here.  Some  of  these,  compared  with  those 
determined  by  Professor  Johnson,  exhibit  an  agreement  that  is  very 
striking  indeed.  It  is  useless  comparing  the  anthracite  coals,  for, 
as  I  have  already  remarked,  the  specific  gravity  is  always  higher, 
cateris  paribus ;  but  I  have  given  below  some  other  analysis  of  bitu- 
minous coals,  and  they  agree  fairly  well  in  the  relation  between  the 
specific  gravity  and  the  amount  of  ash. 

Belleville  District,  Illixois.* 


Specific  Gravity. 

Ash.' 

1 

2 
3 

4 

1-293 
1-296 
1-315 
1-240 

4-50  to  5-40 

8-60 

8-90 

1301 

*  Coal  Begions  of  America.    J.  Macfarlane,  H.A.|  p.  425. 


Hardman — On  Analysis  of  Coah  and  Ironstones. 

Iin)LLVA  CoAL-FlELD.* 


637 


Specific  Gravity. 

Ash. 

1-176 

0-3 

1-230 

2-0  to  30 

1-264 

2-6 

1-28 

6-6 

1-29 

4-6 

1-32 

60 

Ohio. — ^Block  Coal. 

In  six  analyses  the  specific  gravity  ranges  from  1*247  to  1*284. 

And  the  ash  from, 3*18    to  1.16. 

Apparently  reversing  the  matter.     However,  both  the  range  of  ash 
and  of  the  specific  gravity  is  very  small  here. 

Among  English  and  Scotch  coals,  as  well  as  other  Irish  coals,  a 
tolerably  fair  relation  seems  to  exist  in  this  way,  as  the  following 
examples  will  show. 


Name  of  Coal. 

Sp.  Gr. 

Ash. 

Where  PublUhed. 

Scotch  (Fordel  Splint),    . 

1-25 

4-0 

\  Coal  Fields  of  Great  Britain. 
Prof.  Hull,  p.  406. 

Newcastle  (Cans.  Hartly, 

1-26 

60 

Alfreton,  Derbyshire, 

1-235 

204 

Chemical  Technicology. 
Drs.  Bonald  and  Bichardson. 

„        Cannel,   .    .    . 

1-278 

4-64 

Liveipool  Goal,      .    .     . 

1-260 

4-62 

(Vol.    i.,    pt.    ii.,    Analytical 
;      Table,  p.  1. 

Newtastle-on-Tyne  Birtley 

1-270 

400 

Ballycastle,  Ireland,   .    . 

1-273 

4-20 

Tiaboratory  Notes,  Mus.  Ir.  Ind. 
Technicologist.     1864. 

Lough  Allen,  Leitrim,     . 

1-336 

7-62 

Do.                          do. 

Do.               do.       .     . 

1-369 

T-63 

Do.                          do. 

Do.               do.       .    . 

1-382 

17-7 

L.  Studdert,  LL.D., "  Jour.  EL 
Geo.Soc.I.,"VoLiii.,p.l36. 

So  far  then,  it  would  appear,  that  within  certain  limits  the  specific 
gravity  of  a  coal  is  a  tolerably  fair  guide  to  the  quality  of  it.  For 
instance,  one  would  not  be  far  wrong  in  putting  down  a  coal  of  1*35 
fipeciflc  gravity  as  containing  over  10  per  cent,  of  ash,  while  one  of 
1*25  wo^d  be  almost  free  from  it. 

Ibok-stones. — In  the  shales  and  fire>clays  of  the  middle  series  of 
the  Tyrone  coal-measures  there  is  a  good  deal  of  iron-stones,  which 
occur  both  in  beds  and  nodules,  the  former,  in  one  or  two  instanceSi 


•  Op.  cit.y  p.  401. 


538  Proceedings  of  the  Royal  Imh  Academy, 

from  1  to  2  feet  thick,  the  latter  abundant.  None  of  them  have  been 
ever  worked  to  any  extent  bo  far  as  is  known.*  They  have  the  nsnal 
composition  of  clay-ironstone,  and  contain  about  the  average  per  cent- 
age  of  iron.  I  have  examined  some  of  them,  but  only  for  the  amount 
of  iron,  and  the  presence  or  absence  of  sulphur  and  phosphorus,  as  a 
more  complete  analysis  would  add  nothing  interesting  to  our  know- 
ledge of  such  minerals.  The  specimens  were  all  obtained  from  tha 
neighbourhood  of  Coal-Island. 

AlTALYSES  OF  IrON-STONES,  DlTKOAlTKON  CoAL-Fl£IJ). 

No.  1. — Thin  seam  of  ironstone  from  above  the  shinino  seaic. 

Metallic  iron,    .     .     35 '50  per  cent. 
Neither  sulphur  nor  phosphorus  present. 

No.  2. — Iron-stone  nodules  above  Gobtkaskea  coal. 

Metallic  iron,    .     .     34*40  per  cent. 
Neither  sulphur  nor  phosphorus  present. 

No.  3. — Iron-stone  nodules  above  Belttbot  coal. 

(fl.)  Metallic  iron,      .     .     32*50  per  cent. 
Neither  sulphur  nor  phosphorus. 

(5.)  Metallic  iron,      .     .     21*70  per  cent. 

No  sulphur :  a  trace  of  phosphorus. 

(<?.)  ?  Black  band  ironstones. 

Metallic  iron,     .     .     23*60  per  cent. 

No  sulphur :  a  trace  of  phosphorus. 

No.  4. — Iron  nodules  above  Derby  coal. 

Metallic  iron,     .     .     28*80  per  cent. 
No  sulphur :  no  phosphorus. 


*  Traces  of  an  old  iron  furnace  are  found  in  the  townland  of  Deny,  near  the 
road  leading  from  Derryrale  to  Stewartstown,*  and  a  quantity  of  slag  lies  about. 
It  is  possible,  therefore,  that  some  of  the  iron-stones  aboye  the  Deny  coal  wera 
formerly  smelted. 


Kelly — On  a  Case  of  Polydactyliam.  639 


XLVI. — On  a  Case  op  Poltdacttlism.  Witli  Plates  36, 37, 38,  and  89. 
By  J.  E.  Kelly,  Surgeon  to  the  Jervis-street  Hospital,  Lecturer 
on  Anatomy  and  Physiology,  &c.,  &c. 

[Bead  14th  Febraary,  1876.] 

The  peculiarities  which  I  have  noted  were  ohseired  in  the  body  of 
a  female,  aged  about  45  or  50,  spare,  with  good  muscular  development, 
and  anatomically  a  virgo  intaeta.  She  presented  no  other  external 
congenital  peculiarities  besides  those  represented  by  the  casts  ex- 
hibited, except  that  she  appeared  to  have  had  a  strabismus, 
and  her  incisor  teeth  projected  almost  directly  forward.  The 
right  hip  afforded  an  excellent  example  of  a  traumatic  dislo- 
cation of  very  long  standing,  with  contraction  of  the  acetabulum, 
atrophy  of  the  head  of  the  femur,  remarkable  development  of  liga- 
mentous tissue  anteriorly  and  inf  eriorly,  and  a  fissure  in  the  capsular 
ligament  leading  to  the  abnormal  receptacle  for  the  head  of  the  femur, 
which  was  a  smooth  cavity  under  the  gluteus  medius  muscle  (no  trace 
of  the  gluteus  minimus  remaining),  lined  by  a  glistening  membrane 
which,  at  that  part  over  the  dorsum  ilii,  covered  a  very  dense  layer 
of  fibrous  tissue.  The  psoas  muscle  was  represented  by  a  thin  cord  of 
fibrous  tissue,  but  the  iliacus  and  all  the  other  muscles  about  the  joint 
were  well  developed.  The  arterial  system  was  highly  developed,  and 
cutaneous  vessels,  ordinarily  imperceptible,  attained  a  remarkable 
size ;  both  ulnar  arteries  were  of  the  aberrant  type,  and  lay  over  the 
fascia  in  their  course.  Both  stylohyoid  muscles  were  absent ;  the  left 
renal  vein  passed  posteriorly  to  the  aorta ;  the  vermiform  appendix 
was  about  five  inches  long,  and  dilated  towards  its  termination.  I  ob- 
served no  other  peculiarities  worth  noting  except  those  affecting  both 
hands  and  the  left  foot. 

The  hands  were  both  heptadactylous,  and  the  left  foot  was  an  ex- 
ample of  spurious  tridactylism,  owing  to  the  double  syndactylism  which 
had  occurred.  The  supernumerary  digits  were  on  the  radial  or  volar 
side  of  the  hands,  and  may  be  regarded  as  cases  of  reduplication  of 
the  poUex.  This  was  indicated  by  the  length  and  direction  of  the  meta- 
carpal  bones,  the  muscular  attachments,  and  the  vascular  and  nervous 
relations.  The  points  of  opposition  for  the  digits  of  the  right  hand 
were  three :  the  apex  of  the  first  thumb  or  the  spine ;  the  dorsal  sur- 
face of  the  head  of  the  first  phalanx  of  the  second  thumb  ;  and  the 
distal  extremity  of  the  third  thumb.  On  the  left  hand  there  was  but 
one  point,  the  head  of  the  first  phalanx  of  the  second  thumb,  off 
which  the  next  (second)  phalanx  was  dislocated.  Over  these  pointa 
were  developed  bursse,  and  the  cuticle  was  thickened. 

The  Bones  of  the  Right  Hand  :— 

The  lower  end  of  the  radius  normal.  The  ulna: — On  the  apex  of 
the  styloid  process  was  a  facet  which  articulated  with  the  os  trique- 
tnun  and  the  unciform. 

B.  I.  A.  PKOC,  SBB.  n.,  VOL.  Tl.y  scnKCi.  8  H 


640  Proceeding$  of  the  Royal  Irish  Academy. 

The  Bcaphoid : — ^Defective  at  that  part  nonnally  articulating  with 
the  trapezoid. 

The  aeroilunar : — Prolonged  very  much  to  ulnar  side,  where  it  ai^ 
ticulated  with  the  entire  of  the  inter-articular  fibro-cartilage — a  very 
large  facet  for  the  unciform. 

The  cuneiform  : — Indistinguishable  as  a  separate  bone. 

The  pisiform  : — ^Also  indistinguishable. 

The  trapezium  had  an  additional  facet  at  the  site  of  the  external 
angle,  for  uliculution  with  Ihe  first  metacarpal  bone.  The  groove  on 
the  anterior  surface  indistinct.  Another  facet  for  the  **  anterior  tra- 
pezoid." 

The  trapezoid  posterior  : — ^Very  large,  extending  upwards  to  the 
level  of  the  head  of  the  os  magnum,  which  it  resembled.  A  constriction 
was  indicated  at  the  level  of  the  ordinary  bone,  and  the  additional 
portion  seemed  to  be  borrowed  from  the  scaphoid,  which  was  deficient 
to  a  corresponding  extent.  The  bone  did  not  reach  the  anterior  surface 
of  the  carpus. 

The  anterior  trapezoid(?)  : — About  the  size  of  a  large  pea ;  wedge- 
shaped,  with  the  base  anteriorly  occupying  the  position  of  the  anterior 
surface  of  the  trapezoid  proper.  It  articulated  above  with  the  poste- 
rior trapezoid  and  the  scaphoid,  below  with  the  third  metacarpal  bone 
(that  of  the  index  finger),  and  latterly  with  the  trapezium  and  the  os 
magnum. 

The  08  magnum  : — The  head  was  not  rounded  on  the  outer  side ; 
an  additional  facet  for  the  anterior  trapezoid. 

The  unciform  : — Large,  no  process ;  a  very  large  facet  for  the  semi- 
lunar bone,  and  another  on  its  anterior  and  upper  surface  for  the  os 
triquetrum. 

The  "  08  triquetrum" : — Situated  anteriorly  to  the  unciform  and  the 
ulnar  extremity  of  the  semi -lunar  bone,  internal  to  which  one  of  the 
angles  projected  backwards,  and  presented  its  apex  on  the  posterior 
surface  of  the  carpus.  It  presented  two  surfaces,  three  margins,  and 
three  angles.  The  surfaces  were  both  rough,  and  had  trirc^iate  de- 
pressions, indicating  the  fusion  of  the  bones ;  the  inner  or  ulnar  surf  ace 
gave  attachment  to  the  hjrpothenar  muscles,  the  outer  or  radial  entered 
into  the  formation  of  the  anterior  carpal  concavity.  The  anterior  margin 
gave  attachment  to  the  annular  ligament;  the  superior  edge  had  attached 
to  it  a  very  strong  radio-triquetral  ligament.  The  posterior  margin 
was  divided  into  two  parts :  the  inferior  narrow,  and  attached  by  a 
ligament  to  the  anterior  surface  of  the  unciform,  corresponding  to  the 
position  of  the  process ;  the  superior  portion  broader,  with  an  articular 
facet  for  the  unciform  bone.  The  anterior  angle  was  tubercular,  and 
gave  attachment  to  the  tendon  of  the  flexor  carpi  ulnaris.  The  pos- 
terior angle  had  a  smooth  facet  for  articulation  with  the  apex  of  the 
ulnar  styloid  process,  and  it  also  gave  attachment  to  the  internal  lateral 
ligament.  The  inferior  angle  had  attached  to  it  ligaments  extending 
to  the  bases  of  the  last  two  metacarpal  bones. 


Kelly — On  a  Case  of  Polydadylism.  541 

The  metacarpus  consisted  of  six  bones : — 

I.  Two  facets  on  base  for  trapezium  and  second  metacarpal ;  head, 
round  and  articular. 

II.  Two  facets  on  base  for  trapezium  and  first  metacarpal ;  the  head 
expanded  and  indicating  a  tendency  to  subdivision ;  one  large  facet 
for  both  phalanges. 

III.  Deficient  in  its  normal  characters  as  second  metacarpal  bone ; 
^ve  facets  on  base,  the  additional  one  for  the  anterior  trapezoid. 

IV.,  v.,  VI.,  normal,  or  rather  corresponding  to  the  third,  fourth, 
^nd  fifth  metacarpals. 

Phalanges : — That  on  first  pollex,  and  the  terminal  on  second  poUex, 
ended  in  a  spine,  and  bore  no  nails ;  nails  were  developed  on  all  the 
other  fingers. 

The  Bones  of  the  Left  Hand : — ^I  shall  only  allude  to  those  which 
•differ  from  the  corresponding  bones  of  the  right  hand,  as  both  members 
presented  the  same  general  peculiarities. 

The  scaphoid : — Very  large.  It  seemed  to  have  attached  to  it  the 
portion  which  was  in  excess  in  the  trapezoid  of  the  right  hand,  and 
here  also  a  constriction  indicated  the  fusion  of  two  bones.  This  dis- 
puted portion,  or  complemental  process,  in  the  right  hand,  was  attached 
to  the  scaphoid  by  a  very  strong  interosseous  Kgament. 

The  trapezoid : — Comparatively  small. 

The  OS  triquetnim  : — In  two  segments,  the  upper  and  lower,  the 
latter  resembling  the  unciform  process  in  size,  position,  and  attach- 
ments. It  was  bound  to  the  unciform  bone  and  to  the  upper  segment 
by  strong  ligaments ;  no  indication  of  a  synovial  articulation.  In  every 
•other  respect  the  bone  resembled  that  in  the  right  hand. 

The  metacarpus : — 

I.  Instead  of  having  a  head  with  an  articular  facet,  as  on  the  right 
«ide,  ended  in  a  spine  which  was  capped  by  a  cartilaginous  ferule ; 
41  rudimentaiy  phalanx,  which  was  separated  by  a  synovial  cavity,  and 
gave  attachment  to  some  of  the  muscles. 

II.  Base  articulated  with  first  and  third,  as  well  as  with  the  tra- 
pezium.    The  head  articulated  with  only  one  phalanx. 

All  the  digits  except  the  first  pollex  bore  nails. 

III.  As  before  mentioned,  the  base  articulated  with  that  of  II., 
an  abnormality  which  did  not  occur  in  the  right  hand,  and  of  much 
anatomical  interest. 

Phalanges  : — First  phalanx  of  third  pollex  was  rounded  off  at  its 
proximal  end,  and  attached  by  a  dense  fibrous  cord  to  the  side  of  the 
metacarpo-phalangeal  articulation  of  pollex  two,  where  there  was  a 
normally  placed  sesamoid  bone  on  the  inner  side.  Another  sesamoid 
bone  was  in  the  fibrous  cord. 

The  second  and  third  phalanges  of  the  same  pollex  (three)  were 
united,  but  their  original  separation  was  indicated  by  a  node,  and  by 
the  difference  in  the  direction  of  their  axes. 

The  Muscles  of  the  Bight  Hand :  Anterior  Surface : — ^Flexor  carpi 

8H  2 


642  Proceedifigi  of  the  Soyal  Irish  Academy. 

radialis  and  ulnaris,  normal;  palmarialongns,  absent;  p.  brevis,  nonnal; 
flexor  sublimis  and  profundus  digitorum,  normal ;  lumbricales,  normal. 

Musculus  access,  ad  lumbricalem  primum  : — A  slip  about  tbe  size 
of  a  lumbricalis  arose  from  tbe  deep  surface  of  the  annular  ligament 
by  a  tendon ;  inserted  witb  tbe  first  lumbricalis. 

Flex.  pel.  long. : — Origin  normal ;  tbe  tendon  divided  at  cleft  be- 
tween second  and  third  pollices  into  two  slips,  which  were  inserted 
into  the  third  or  terminal  phalanges,  and  gave  off  slips  to  the  conti- 
guous sides  of  the  bases  of  the  second  phalanges  of  their  respectiTe 
digits. 

Abductor  pollicis : — Origin  normal ;  insertion,  in  two  parts :  one  into 
the  base  of  the  terminal  bone  of  the  first  poUez,  on  its  inner  aspect ; 
the  other,  by  a  narrow  tendon,  which  ran  along  the  same  side  of  that 
bone  to  its  apex,  where  it  ended  in  a  fibrous  cap.  Action,  to  abduct 
and  flex  first  pollex. 

Opponens  pol. : — Origin  normal ;  insertion  into  the  radial  edge  of 
the  metacarpal  bone  of  first  pollex. 

Adductor  pol.: — Origin  normal;  insertion  into  the  base  of  first 
phalanx  of  third  pollex. 

Flex.  brev.  pol. : — Only  one  head,  the  deeper ;  origin  normal ;  two 
insertions  :  the  first  into  the  outer  edge  of  the  metacarpal  bone  of  first 
pollex,  close  to  its  head ;  the  second,  into  the  base  of  the  first  phalanx 
of  the  third  pollex.  The  first  portion  might  be  regarded  as  an  add. 
pol.  primi. 

Transversus  manus : — Origin,  the  anterior  surfaces  of  the  meta- 
carpal bones  of  the  middle  and  ring  fingers,  and  the  adjacent  metacarpo- 
phalangeal ligaments ;  the  two  slips  united,  and  were  inserted  into 
the  base  of  the  first  phalanx  of  third  pollex,  on  the  inner  side. 

Mus.  access,  ad  transTersum  manus : — Origin,  the  fibrous  tissue 
giving  common  insertion  to  the  numerous  muscles  inserted  into  the 
base  of  the  first  phalanx  of  third  pollex,  on  its  inner  side ;  insertion, 
radial  side  of  base  of  first  phalanx  of  second  pollex. 

Interpollicaris  : — Three  slips: — First:  origin,  inner  side  of  first 
phalanx  of  third  pollex ;  insertion,  outer  edge  of  metacarpal  of  first 
pollex,  where  it  was  overlapped  by  abduct,  pol.  prim,  and  oppon.  pol. 
Second  slip :  origin,  anterior  metacarpo-phalangeal  ligament  of  third 
pollex;  insertion,  inner  side  of  base  of  terminal  bone  of  first  pollex,  and 
the  anterior  surface  of  its  metacarpal  bone.  Third  slip  (interosseous)  : 
origin,  from  anterior  surface  and  inner  edge  of  metacarpal  of  first 
pollex ;  insertion,  into  base  of  first  phalanx,  and  by  tendinous  slips  into 
base  of  second  phalanx  of  second  pollex. 

Flexor  pol.  secundi  et  tertii : — Origin  tendinous,  from  the  tra- 
pezium and  the  anterior  trapezoid.  It  divided  into  two  fieshy  bellies, 
which  were  inserted  into  the  bases  of  second  and  third  pollices. 

The  Muscles  of  the  Left  Hand  :  Anterior  Surface : — All  the  long 
muscles  normal,  except  the  fiexor  pol.  long.,  the  tendon  of  which 
divided  at  cleft  between  second  and  third  pollices:  one  part  went  to 


Kelly — On  a  Case  of  Polydactylism^  643 

-second  pollez^  and  at  head  of  first  phalanx  divided  into  three  slips^  the 
central  of  which  passed  on  to  the  terminal  phalanx ;  the  two  lateral 
were  inserted  into  sides  of  hase  of  second  phalanx;  that  part  of  the 
tendon  going  to  the  third  pollex  was  inserted  into  the  hase  of  the  ter- 
minal phalanx. 

Lnmbricales : — The  first  was  very  large,  and  divided  into  two  slips  : 
one  had  the  normal  insertion;  the  other,  into  the  first  phalanx  of 
third  pollex  (lumbricalis  ad  pollicem  tertium  ?). 

Abductor  pol. : — Origin  normal ;  three  insertions :  first,  into  anterior 
surface  of  metacarpal  of  first  pollex ;  second,  into  an  aponeurotic  arch 
extending  from  the  apex  of  first  pollex  to  base  of  first  phalanx  of 
second  pollex ;  third,  partly  into  base  of  first  phalanx  of  second  pollex, 
and  partly  into  tlie  aponeurotic  arch. 

Oppon.  pol. : — Origin  normal ;  insertion  into  radial  edge  of  the 
metacarpal  bone  of  first  pollex,  and  tendon  of  extensor  oss.  metacarp. 
pol. 

Add.  pollicis : — Origin  normal ;  insertion  into  base  of  first  phalanx 
of  third  pollex,  and  slightly  in  that  of  second  pollex. 

Flex.  brev.  pol. : — Three  origins :  two  corresponding  with  the  heads 
of  the  normal  muscle,  the  third  from  base  of  metacarpd.  bone  of  third 
pollex.  Insertions,  four — ^first,  into  outer  edge  of  first  pollex;  second, 
into  the  inner  edge  of  the  same  bone  ;  third,  by  a  small  tendon  into 
the  cartilaginous  ferule  on  the  apex  of  first  pollex ;  fourth  and  largest 
(consisting  of  the  entire  of  the  portions  from  the  trapezium  and  annular 
ligament,  and  that  from  the  base  of  the  metacarpal  bone  of  pollex 
three),  inserted  into  base  of  first  phalanx  of  third  pollex.  The  third  head 
was  separated  from  the  rest  of  the  muscle  by  the  deep  palmar  arch. 

Musculus  access,  ad  trans,  manus : — ^The  transversus  manus  was 
absent,  but  I  have  applied  the  term  "accessorius  "  to  this  muscle,  owing 
to  its  similarity  to  that  muscle  in  the  other  hand,  in  origin  and  inser- 
tion; but  it  differed  in  position,  as  it  overlapped  the  interpoUicares, 
while  the  others  lay  under  these  muscles. 

Interpollicaris: — Two  slips,  both  wedge-shaped,  with  their  apices 
reversed.  First,  superficial ;  origin,  fieshy,  from  base  of  first  phalanx 
of  second  pollex  ;  insertion,  tendinous,  into  inner  side  of  metacarpal 
bone  of  first  pollex.  Second  slip  :  origin,  from  inner  edge  of  meta- 
carpal bone  of  first  pollex,  and  its  anterior  surface ;  insertion,  into  the 
base  of  the  first  phalanx  of  second  pollex. 

The  Muscles  of  the  Right  Hand :  Posterior  Surface  : — Supinator 
long,  and  extensor  carp,  longior,  normal ;  ext.  carp.  rad.  brev.  sends 
fllip  to  base  of  metacarpal  bone  of  index  finger ;  ext.  carp,  ulnaris, 
normal. 

Ext.  digitorum  communis  : — The  tendon  to  the  index  finger  was 
small,  and  ended  in  the  tendon  of  ext.  indicis ;  none  to  the  little  finger. 

Ext.  min.  digit. — Sends  a  slip  to  aponeurosis  over  the  last  inter- 
osseous space. 

Ext.  oss.  metacarp.  pol. : — Origin  normal ;  course  normal ;  divided 
into  two  slips,  as  is  frequently  seen :  one  inserted  into  base  of  metacarpals 


644  Ptvceedings  of  the  Royal  Insh  Academy. 

bone  of  first  poUex ;  the  other,  into  the  base  of  the  terminal  bone  dt 
same  (ext.  intemod  pol.  primi). 

Ext.  prim,  intemod.  pol. : — Origin  normal ;  insertion  into  base  of 
second  phalanx  of  second  poUex.  An  aponeurosis  from  the  tendon  of 
last,  and  from  the  bone  close  to  its  insertion,  passed  this  tendon,  to  the 
majority  of  the  fibres  passing  over  it. 

Ext.  secnndi  int.  pol. : — Origin  and  course  normal ;  joined  with 
tendon  of  last  muscle  to  form  a  common  tendon,  "which  divided  at  the 
deft  between  second  and  third  pollex.  The  portion  corresponding  to  this 
muscle  divided  at  head  of  first  phalanx  of  third  pollex  into  three  slips  r 
the  middle  passed  over  the  joint,  and  was  inserted  into  base  of  terminal 
phalanx;  the  two  lateral  were  inserted  into  the  base  of  second  phalanx. 
This  is  the  reverse  of  the  arrangement  with  ordinary  dorsal  digital 
aponeurosis,  and  approximates  to  the  flexor  arrangement  of  tendon. 

Ext.  indicis : — Origin  normal,  but  prolonged  up  as  far  as  the  at- 
tachment of  the  supinator  brevis ;  course  normal ;  insertion  normal ; 
tendon  joined  by  small  slip  from  ext.  com.  dig. 

The  Muscles  of  the  Left  Hand : — Posterior  surface  :  supinat.  long, 
and  extensors  of  the  carpus,  normal. 

Extensor  com.  digitorum : — ^Divided  into  two  tendons  only,  which 
went  to  the  middle  and  ring  fingers ;  no  trace  of  a  tendon  to  the  index 
or  little  finger. 

Extensor  ossis  met.  pol. : — Origin  normal;  divided  into  three  slips : 
first,  inserted  into  base  of  metacarpal  bone  of  first  pollex  (ext.  oss. 
met.  pol.  prim.);  second,  into  cartilaginous  nodule,  at  apex  of  first 
pollex,  which  is  the  homologue  of  the  terminal  bone  of  first  pollex  on 
right  hand  (ext.  intemod.  pol.  prim.);  third,  into  an  aponeurosis  on 
the  back  of  the  first  phalanx  of  second  pollex,  which  was  formed  by 
the  tendon  of  this  and  three  other  muscles  (ext.  primi  intemod.  pol. 
secund.)  Between  the  two  tendons  last  mentioned  a  web  of  dense 
fascia  extended,  which  was  closely  connected  with  both,  and  resembled 
the  stmcture  described  in  the  right  hand.  The  concave  margin  con- 
stituted the  arch  into  which  were  inserted  some  of  the  short  muscles- 
of  the  anterior  group. 

Ext.  primi  intemod.  pol. : — Origin  normal ;  insertion  into  the 
same  aponeurosis  as  last. 

Ext.  sec.  intemod.  pol. : — Origin  normal,  divided  into  two  tendons ;: 
the  external  much  the  larger,  inserted  together  into  the  same  aponeu- 
rosis as  last  two  muscles.  This  aponeurosis,  formed  by  union  of  the 
four  tendons,  expanded  towards  the  head  of  the  first  phalanx,  and 
formed  a  cap  which  enclosed  it,  and  was  inserted  into  the  base  of  the 
second  phalanx. 

Ext.  indicis : — Origin  normal ;  insertion  normal.  It  received  ne 
slip  from  ext.  digit,  communis. 

The  Arteries  of  Bight  Hand : — The  ulnar  artery  gave  off  a  poste- 
rior carpal  and  a  communicating  branch,  and  then  passed  across  the 
palm  to  the  radial  side  of  second  pollex,  along  which  it  continued  as  its. 
external  digital  artery.    The  superficial  palmar  arch  was  completed 


Eblly — On  a  Case  of  Polydactyliam.  64$ 

b J  a  very  large  snperfioialis  Tolse^  which  lay  superficial  to  the  musolce 
of  the  thenar  eminence.  The  arch  sent  a  branch  to  the  inner  side 
of  the  little  finger ;  one,  before  mentioned,  to  the  outer  side  of  the 
second  pellex ;  and  branches  to  the  clefts  between  all  the  digits  except 
to  that  between  second  and  third  pollices,  which  received  a  transverse 
branch  which  subdivided,  from  that  between  the  third  poll  ex  and  the 
index  finger.  The  radial  side  of  first  pollex  got  a  branch  from  the 
radial  artery,  while  in  the  intertendinous  space ;  while  the  other  side 
received  a  branch  from  the  superficiahs  voIsb. 

The  radial  artery  wound  round  the  wrist,  passing  under  a  distinct 
tendinous  arch  to  the  back  of  the  hand,  whence  it  passed  forward  be- 
tween the  second  and  third  metacarpal  bones.  It  distributed  its 
usual  branches,  and  certain  others  which  might  be  termed  dorsalis 
pollicis  primi,  d.  p.  secundi,  and  d.  p.  tertii.  The  deep  palmar  arch 
was  small.     This  description  suits  the  left  radial  artery  also. 

Left  Hand : — The  xilnar  artery,  as  in  the  right,  crossed  to  the 
radial  side  of  pollex  two.  It  was  completed  by  a  similarly  placed  super- 
ficialis  vol®,  which,  however,  was  much  smaller  than  the  right,  and 
gave  off  an  equal  number  of  branches,  which  were  similarly  distributed, 
except  that  the  digital  artery  between  pollex  two  and  three  was  given 
ofE  from  the  outer  of  the  two  branches  supplying  the  compound  digit. 
A  remarkable  branch,  larger  than  either  the  radial  or  ulnar  artery, 
passed  under  the  annular  ligament,  with  the  median  nerve,  and  joined 
the  superficial  palmar  arch.  Apparently,  this  was  a  very  large  arteria 
mediana  from  the  interosseous  artery. 

The  Nerves,  Right  Hand  : — ^The  ulnar  :  the  superficial  portion 
normal,  the  deep  branch  supplying  all  the  short  muscles,  except  the 
abductor  and  opponens  pollicis. 

The  median  nerve : — The  inner  division  supplied  the  middle  finger 
and  the  contiguous  sides  of  the  index  and  ring.  It  received  no  com- 
municating branch  from  the  ulnar.  The  external  division  supplied 
the  radial  side  of  the  index  finger,  both  sides  of  second  and  third  polHces, 
and  the  ulnar  side  of  first  pollex.  The  radial  side  was  supplied  by  a 
branch  &om  the  radial  nerve  which  came  from  the  back  of  the  wrist. 
A  distinct  branch  ramified  between  the  second  and  third  pollex,  but 
the  vascular  supply  was  only  collateral.  On  the  posterior  surface  of 
the  hand  the  posterior  branch  of  the  ulnar  supplied  two  and  a-half 
fingers ;  the  remainder  received  branches  from  the  radial  nerve. 

The  Left  Hand : — The  same  description  is  applicable  to  the  nerves 
of  this  member,  with  a  few  trivial  exceptions.  The  ulnar  sent  a  com- 
municating branch  to  the  median,  and  the  latter  nerve^  in  addition  to 
supplying,  as  in  the  right  hand,  the  opponens  and  abductor  pollicis, 
also  sent  filaments  to  the  superficial  portions  of  the  fiexor  brevis 
pollicis. 

The  Foot : — The  left  foot,  having  but  three  distinct  digits,  was  a 
specimen  of  double  syndactylism,  as  well  as  of  talipes  valgus.  The 
anatomy  of  this  member  presented  few  peculiarities.    The  normal 


646  Proceedings  of  (he  Boyal  Irish  Academy. 

arches  of  the  toot  were  obliterated,  and  the  most  projecting  portion  of 
the  tarsus  was  the  anterior  tubercle  of  the  os  calcis. 

The  Muscles : — Extensor  brevis  digitorum :  insertions;  first  and  third 
normal,  second  and  fourth  into  the  base  of  first  phalanx  of  corresponding 
toe.  Peroneus  longus :  inserted  into  a  well-marked  tubercle  on  the 
outer  side  of  the  os  calcis,  which  most  probably  represented  its  own 
sesamoid  bono.  A  fibrous  band  was  continued  from  this  tubercle  to 
the  normal  insertion  of  the  muscle. 

Tibialis  anticus : — A  slip  from  the  tendon  of  this  muscle  passed 
forwards  to  be  inserted  into  the  head  of  the  first  metatarsal  bone. 

In  the  Vessels  nothing  peculiar  was  observed. 

The  Kervcs : — The  anterial  tibial,  in  addition  to  the  normsl 
branch  between  the  first  and  second  toes,  sent  a  much  larger  branch 
directly  to  the  space  between  the  second  and  third  toes,  where  the 
separation  was  complete.  The  fusion  between  the  toes  was  most 
marked  at  their  anterior  extremities. 

Synovial  cavities  were  developed  between  the  heads  of  the  first, 
second,  third,  and  fourth  metatarsal  bones.  An  articulation  also  ex- 
isted between  the  bases  of  the  first  and  second  metatarsal  bones. 


Moss — On  the  Exploration  of  Ballybetagh  Bog.  647 


XLVII. — Report  ok  the  Exploeatton  op  Billtbetaoh  Bog.     By 
BiCHABD  J.  Moss,  Keeper  of  the  Minerals^  Bx)yal  Dublin  Society. 

[Read  April  10, 1876.] 

About  thirty  years  ago  the  late  Mr.  Sigismund  Moss,  of  Kilteman, 
discovered  an  extensive  deposit  of  the  remains  of  the  Cervus  Mega- 
ceros,  in  a  cutting  which  was  made  through  the  boggy  land  on  the 
south  side  of  Ballybetagh  House,  in  the  parish  of  Kiltemun,  county 
Dublin.  In  addition  to  the  great  homed  deer,  only  one  other  animal, 
the  reindeer  (Cervus  tarandus),  was  represented  amongst  the  remains 
found.  The  fine  specimen  of  the  horns  of  this  animal  discovered  on 
this  occasion  is  now  in  the  Museum  of  the  Bx)yal  DubliQ  Society.  Tho 
cutting  in  which  these  remains  were  discovered  was  made  for  the  pur- 
pose of  turning  the  water  of  the  spring  known  as  the  White  Well, 
into  the  stream  that  flows  through  Kilteman,  and  not  with  any  scien- 
tific object ;  and  thus  it  happened  that  no  accurate  account  of  the  dis- 
covery has  been  published,  and  therefore  it  has  had  but  little  scientific 
value.  Professor  A.  Leith  Adams  and  I  visited  the  locality  early  last 
summer,  and  at  his  suggestion  I  undertook  to  re-investigate  the  matter 
in  conjunction  with  Dr.  Carte,  of  the  Royal  Dublin  Society.  Tho 
ground  being  in  the  possession  of  the  Rev.  Mr.  0*  Sullivan,  of  Leopards- 
town,  we  applied  to  him  for  permission  to  conduct  the  investigation. 
This  he  most  liberally  granted,  and  I  take  this  opportunity  of  express- 
ing our  thanks  to  him. 

Ballybetagh  Bog  lies  at  the  bottom  of  a  glen,  between  two  hills. 
Tanning  almost  due  south  from  Ballybetagh  House.  The  lower  of  the 
two  hills  is  on  the  east  side  of  the  glen ;  it  is  700  feet  above  the  sea 
level,  and  about  100  feet  above  the  bottom  of  the  glen.  The  hill  on 
the  other  side  of  the  glen  is  on^  of  the  range  of  the  Dublin  mountains. 
The  rock  of  this  district  is  granite,  being  part  of  that  band  of  granite, 
about  five  miles  broad,  which  extends  from  the  south  coast  of  Dublin 
bay,  in  a  south-westerly  direction,  into  the  county  Waterford. 

The  first  difficulty  encountered  was  rather  formidable.  No  trust- 
worthy information  could  be  obtained  as  to  the  precise  spot  in  which  the 
remains  had  been  found ;  it  might  have  been  any  place  along  a  cut- 
ting half  a  mile  in  length.  The  opinions  of  old  residents  in  the 
neighbourhood  were  obtained,  but  were  very  contradictory.  Not 
widtiing  to  trust  entirely  to  tradition  or  chance,  I  decided  upon  making 
on  attempt  to  probe  the  ground  at  different  places  along  the  sides  of 
the  old  drain.  For  this  purpose  I  obtained  an  iron  tube,  twelve  feet 
in  length  by  two  inches  in  diameter ;  it  was  longitudinally  bisected, 
the  two  halves  being  held  together  by  end-pieces  screwed  on,  while  a 
movable  iron  collar  clasped  the  middle  of  the  tube.  The  end-piece 
was  sharpened  to  enable  it  to  be  driven  into  the  soft  earth,  this  being 


548 


Prcceedinga  qfthe  Royal  Irish  Academy. 


done  by  means  of  the  apparatus  employed  for  sinking  the  so-called 
Abyssinian  pumps.  After  a  few  trials  in  various  places  along  the 
side  of  the  old  drain — now  quite  full  of  water — I  obtained  a  com- 
pressed section,  which  appeared  to  correspond  with  the  strata  said  to 
oTcrlie  the  bones  of  Mcgaccros  (Oldham,  Journal  Geol.  Soc.,  Dublin, 
vol.  iii.,  p.  252).  Hero,  accordingly,  a  trench  was  commenced,  seventy 
feet  long,  and  from  nine  to  twelve  feet  broad  (fig.  2,  a).  This  trench 
is  represented  in  section  at  a,  fig.  1.     The  direction  in  which  this 


Fiftl 


SCALE    1  mCHalt  YARDS 


Fi^:2 


C-' 


fUMOSS.OEL: 


I 


section  is  taken  is  indicated  by  the  dotted  line  h,j\  fig.  2.  The  first  foot 
of  material  removed  consisted  of  peat ;  under  this  there  was  a  stratum  of 
sand  of  an  average  depth  of  about  two  feet.  The  sand  lay  upon  a  brown- 
coloured  clay,  which  extended  for  about  two  feet,  and  lay  upon  a  bed 
of  rounded  granitic  boulders.  The  spaces  between  the  lower  parts  of 
the  boulders  were  filled  with  a  fine  bluish-grey  clay.  Amongst  the 
boulders,  and  surrounded  with  the  brown  clay,  we  found  nineteen 
skulls  of  Megaceros,  with  the  attached  antlers  greatly  broken ;  also 
many  broken  pieces  of  horn,  and  a  number  of  bones.  The  heads  and 
horns  were  huddled  together  promiscuously,  often  so  tightly  locked 
together  that  there  was  some  difficulty  in  removing  them  from  their 
rocky  bed.  In  many  cases  they  were  securely  wedged  between  the 
boulders,  and  generally  so  situated  that  they  could  only  be  extricated 
by  raising  them  directly  upwards  ;  some  part  woidd  have  been  broken 
by  any  attempt  to  move  them  laterally.  The  smaller  bones  were  found  by 
carefully  examining  between  the  boulders  after  the  heads  had  been 
removed.  On  several  of  the  granite  boulders  I  noticed  a  net-like 
coating  of  vegetable  matter,  closely  resembling  matter  contained  in 
the  cavities  of  many  of  the  skulls.  This  is  so  decomposed  that  I  fear  it 
is  impossible  to  determine  its  nature  with  any  degree  of  certainty.  I 
was  not  satisfied  with  merely  collecting  the  bones  that  lay  amongst 


Moss — On  the  Eqphratum  of  Ballybetagh  Bog.  649 

the  boulders,  but  had  many  of  the  stones  turned  oyer  to  see  if  bones 
lay  under  them.  In  no  case,  however,  did  I  find  a  stone  resting  on 
any  of  the  bones.  Two  of  the  larger  boulders  were  quite  too  heavy  to 
move ;  bones  were  found  in  cavities  partly  under  these,  in  each  case 
on  the  north  side  of  the  boulders.  Kear  one  of  these  boulders  twenty- 
nine  bones  were  found  within  a  space  of  little  more  than  four  square 
feet.  The  general  appearance  which  the  bottom  of  the  trench  pre- 
sented, when  the  remains  of  Megaceros  were  removed,  reminded  me  of 
the  rocky  margin  of  a  mountain  tarn.  It  dipped  slightly  towards  the 
west  side,  as  shown  in  the  accompanying  sketch  (fig.  1,  a).  Judging 
from  the  present  appearance  of  the  ground,  the  water  of  such  a  tarn 
could  not  have  extended  more  than  a  few  yards  to  the  east ;  for  on  this 
side  rises  the  southern  base  of  the  hill  which  forms  the  eastern  side  of 
the  glen.  I  decided  upon  excavating  the  next  trench  further  from 
the  supposed  margin  of  the  tarn,  and  therefore  at  the  west  side  of  the 
drain.  The  point  selected  is  marked  h  on  the  map  (fig.  2).  This 
trench  was  only  eight  feet  square,  but  extended  to  a  much  greater 
depth  than  the  first  trench.  At  a  depth  of  ten  feet  there  was  no  sign 
of  a  stony  bottom,  although  we  had  reached  blue  clay  resembling  that 
found  between  the  boulders  at  the  bottom  of  trench  a.  The  blue  clay 
was  probed  in  every  direction  with  a  stout  stick,  which  was  easily 
forced  into  it  to  the  extent  of  about  3  feet,  but  no  hard  substances 
were  encountered.  The  only  bone  found  was  a  solitary  rib  in  the  brown 
clay,  about  6  feet  from  the  surface.  The  position  of  the  stratum  in 
which  this  rib  occurred  is  shown  by  vertical  shading  at  (?,  fig.  1. 
Although  this  represents  the  section  of  a  trench  made  subsequently,  it 
illustrates  equally  well  the  section  of  trench  h.  This  excavation  was 
not  sufficiently  large  to  bo  worked  with  advantage,  so  it  was  aban- 
doned, and  another  one  commenced  at  a  spot  where  I  thought  there 
would  be  less  difficulty  in  reaching  the  bottom.  The  position  of  this 
trench  is  shown  at  c,  fig.  2,  and  the  section  of  it  at  <?,  fig.  1,  where 
the  various  strata,  corresponding  with  those  encountered  in  the  first 
cutting  (0,  fig.  1),  are  connected  with  them  by  straight  lines.  It 
will  be  observed,  that  the  peat  in  trench  e  is  nearly  twice  as  deep  as 
that  in  a  ;  while  the  stratum  of  sand  has  thinned  oat  to  a  mere  trace. 
The  next  stratum  in  «  is  one  that  was  not  observed  at  all  in  a.  It 
consists  of  a  grey-coloured  friable  clay,  containing  layers  of  vegetable 
matter,  often  moss.  This  clay  contained  in  some  places  numerous 
white  specks,  which  turned  blue  on  exposure.  I  found  a  few  frag- 
ments as  large  as  hazel-nuts.  On  analysis,  this  matter  was  found  to 
consist  almost  entirely  of  ferrous  phosphate,  or  Yivianite.  The  next 
stratum  encountered  in  this  trench  consisted  of  brown  clay,  corres- 
ponding in  appearance  with  that  in  which  the  bones  were  found  in  the 
first  cutting.  The  only  bones  found  in  this,  however,  were  two 
decayed  fragments.  The  brown  clay  stratum  was  about  4  feet  deep, 
and  under  it  lay  blue  clay,  like  that  which  filled  up  the  interspaces 
between  the  boulders  in  trench  a,  I  cannot  tell  how  far  the  blue  clay 
extended.     When  the  trench  had  reached  the  depth  of  12  feet,  we 


650  Proceedings  of  the  Royai  Irish  Academy. 

found  a  few  small  stones,  two  of  granite  and  one  of  limestone ;  one  of 
the  granite  stones  was  polished  on  one  side.  Although  a  pump  was 
constantly  at  work,  the  water  which  leaked  in  from  the  sides  of  the 
trench  gained  on  us  rapidly ;  and  it  was  evident  that  a  greater  depth 
could  not  be  i*eached  without  considerable  difficulty,  so  I  was  reluct- 
antly compelled  to  abandon  this  trench. 

The  next  excavation  was  made  about  30  yards  north  of  the  first 
trench,  and  on  the  same  side  of  the  drain,  but  a  little  further  from  it 
(fig.  2,  d).  The  section  of  this  cutting  closely  resembled  that  of 
trench  a.  The  peat  was  a  little  deeper,  and  contained  a  large  log  of 
wood  in  a  horizontal  position,  probably  a  portion  of  the  stem  of  a  pine- 
tree  of  considerable  size.  At  the  north  end  the  stony  bottom  was  reached 
at  a  depth  of  only  4  feet ;  it  dipped  towards  the  southern  end,  where  it 
was  about  5  feet  from  the  surface.  The  northern  half  of  tliis  trench  did 
not  contain  a  single  fragment  of  bone  or  horn ;  the  southern  half  was 
Hterally  packed  with  them.  The  antlers  were  all  very  much  broken, 
and  fragments  of  horn  were  numerous ;  but  the  smaller  bones  of  the 
skeleton  were  not  as  numerous  here  as  in  trench  a.  By  continuing 
the  excavation  in  a  southerly  direction,  I  should  certainly  have 
obtained  a  large  number  of  heads,  but  there  appeared  to  be  little 
prospect  of  gaining  additional  information  by  such  a  course. 

There  can  be  little  doubt  that  the  trenches  a  and  d  occupy  a  posi- 
tion corresponding  with  the  margin  of  the  lake  or  tarn  which  once 
stretched  along  the  bottom  of  the  glen ;  while  the  trench  <?,  where  we 
failed  to  reach  the  bottom,  and  found  no  bones,  must  have  been  near 
the  centre  of  the  tarn.  Judging  from  the  general  appearance  of  the 
surface,  I  concluded  that  the  opposite  margin  of  the  supposed  tarn 
must  have  been  situated  about  the  place  marked  e,  fig.  2 ;  and 
considering  it  important  to  learn  if  bones  also  abounded  there,  I 
decided  upon  exploring  this  part  of  the  bog.  A  few  yards  to  the  west 
of  this  spot  the  ground  suddenly  rises  several  feet,  and  then,  after  a 
gentle  slope  of  about  50  yards,  there  is  another  sudden  rise,  as  we 
reach  the  high  ground  forming  the  southern  end  of  the  hill,  which 
flanks  the  west  side  of  the  glen  :  the  hill  on  the  east  side  of  the  glen 
is  not  so  high.  In  other  respects  the  two  sides  are  not  dissimilar. 
As  might  be  expected,  the  results  of  this  cutting  closely  corresponded 
with  those  obtained  in  trench  a.  The  strata  passed  through,  however, 
were  more  conformable  to  those  of  trench  c,  the  chief  difference  being 
in  the  thickness  of  each  stratum,  as  may  be  seen  from  the  section 
(«,  fig.  1),  which  needs  no  further  explanation.  The  stony  bottom 
of  this  trench  was  so  even  and  regular,  that  it  presented  the  appear- 
ance of  a  pavement.  It  dipped  towards  the  east  about  as  much  as  the 
bottom  of  trench  a  did  to  the  west.  The  remains  found  here  were 
about  the  same  in  point  of  numbers  as  those  of  trench  a,  but  they  were 
in  a  very  much  worse  state  of  preservation ;  indeed,  several  antlers 
were  not  removed,  as  it  was  found  impossible  to  disturb  them  without 
breaking  them  into  fragments.  It  was  in  this  trench  that  most  of  the 
ribs  and  jaw-bones  were  found.     At  the  southern  end  of  it,  a  log  of 


Moss — On  the  Exploration  of  Ballybetagh  Bog.  551 

wood,  about  4  feet  long  and  18  inches  in  diameter,  was  found,  with 
one  end  resting  on  the  stones,  and  the  other  close  under  the  turf. 
This  log  was  the  only  piece  of  wood  found  accompanjdng  the  bones  in 
any  of  the  cuttings.  Its  decayed  condition  rendered  identification  a 
matter  of  difficulty  ;  it  most  resembled  oak. 

The  next  trench  (fig.  2,/)  was  cut  at  the  southern  end  of  the  first 
excavation,  for  the  purpose  of  ascertaining  how  far  the  brown  clay  in 
which  the  bones  were  found  extended  towards  the  east.  At  the  east 
end  of  this  cutting  the  granite  rock  was  reached,  after  passing  through 
3  feet  of  granite  sand,  no  brown  clay  haying  been  encountered.  A 
little  to  the  west  of  this  spot  a  narrow  tongue  of  brown  clay  protruded 
into  the  sand,  dividing  it  about  equally  into  an  upper  and  a  lower 
stratum.  The  lower  stratum  of  sand  thinned  out  towards  the  west, 
being  replaced  by  the  brown  clay.  About  the  spot  where  the  lower 
stratum  of  granite  sand  disappeared,  and  the  brown  clay  rested  upon 
the  stony  bottom  of  the  trench,  several  long  bones  were  found  between 
the  granitic  boulders.  A  little  to  the  west  of  these  bones  we  found  a 
head,  with  large  antlers,  in  a  good  state  of  preservation. 

In  none  of  these  excavations  did  we  find  a  true  marl :  the  clays 
which  have  been  referred  to  were  dmost  entirely  free  from  calcium  car- 
bonate, and  had  every  appearance  of  a  granitic  origin.  Not  many  yards 
north  of  the  place  where  these  clays  were  found,  a  light-coloured  marl, 
rich  in  calcium  carbonate,  makes  its  appearance,  almost  immediately 
under  the  turf.  A  trench  extending  into  this  marl  was  opened  at  the 
north  end  of  the  glen  (fig.  2,  y),  about  300  yards  south  of  Ballybetagh 
House,  and  the  same  distance  north  of  the  other  trenches.  One  end 
of  this  cutting  was  at  the  very  base  of  the  hill  which  fianks  the  east 
side  of  the  glen.  Here  granite  boulders  were  met  with  immediately 
under  the  surface,  and  as  the  excavation  progressed,  the  bed  of 
boulders  was  found  to  dip  towards  the  west  to  about  the  same  extent 
as  the  side  of  the  adjoining  hill.  The  turf  varied  from  a  few  inches 
to  about  3  feet  in  depth,  and  lay  upon  a  stratum  of  fine  granitic  sand, 
traversed  by  occasional  layers  of  coarse  sand.  Under  the  sand  there 
was  a  stratum  of  brown  clay,  about  2  feet  deep  at  the  west  end  of  the 
trench,  and  gradually  thinning  out  towards  the  east  end,  where  it 
became  sandy  in  character.  In  the  sandy  part  of  this  brown  clay 
were  found  two  fragments  of  bone,  much  decayed.  Under  the  brown 
clay  lay  the  marl,  containing  a  large  quantity  of  vegetable  matter, 
but  without  any  visible  traces  of  shells.  The  marl,  when  examined 
microscopically,  was  found  to  abound  in  diatoms,  in  which  respect  it 
differed  entirely  from  all  the  clays,  as  no  diatoms  could  be  detected  in 
any  of  them.  At  a  depth  of  10  feet,  the  marl  continued  unaltered  in 
character.  The  influx  of  water  prevented  the  excavation  from  being 
conducted  to  a  greater  depth.  It  is  noteworthy  that  the  only  frag- 
ment of  bone  which  this  trench  yielded  was  found  in  a  clay  corres- 
ponding in  appearance  with  that  in  which  the  bones  were  found  at 
the  other  end  of  the  glen.     In  the  latter  case,  however,  the  brown 


652  ProeeedingB  of  the  Boyal  Irish  Academy. 

clay  lay  upon  granite  bonlden ;  ^liile  in  tlie  f  onner  case,  the  clay  is 
separated  from  the  boulders  by  a  deep  stratum  of  marl. 

The  remains  found  in  the  course  of  this  exploration  represent 
about  fifty  indiyiduals  of  Cenrus  Megaceros.  Taken  in  conjunction 
with  those  prcTiously  found  here,  we  have  a  total  of  about  eighty  in- 
dividuals of  the  great-homed  deer,  apparently  all  males,  and  one  rein- 
deer ;  and  yet  by  far  the  greater  part  of  this  remarkable  Pleistocene 
formation  remains  still  unexplored. 

Br.  Carte  has  examined  the  bones,  and  supplied  the  following  list 
of  them : — 

Lut  of  the  hones  of  Cervue  MegaceroB  found  in  the  cuttings  made  at 
Ballghetaghf  during  the  month  of  August,  1875. 

Thirty-six  skulls,  with  antlers  more  or  less  broken,  and  many 
fragments  of  antlers. 

Fifteen  shed  antlers,  much  mutilated. 

Six  Mandibular  rami,  representing  three  individuals. 

Ten  Atlas  bones,  perfect,  and  two  broken. 

Two  Axes. 

Six  Cervical  vertebrae. 

Three  Dorsal     do. 

One  Lumbar      do. 

Two  portions  of  Sternum. 

Two  fragments  of  Ilium,  with  glenoid  cavity. 

Thirteen  ribs,  nearly  perfect,  and  a  number  of  fragments. 

Four  Humeri,  perfect,  and  three  imperfect,  representing  six  indi- 
viduals, one  very  young. 

Six  Scapulae,  all  more  or  less  broken,  representing  five  indi- 
viduals. 

Five  Radii,  and  one  imperfect. 

Two  Sacra,  and  odc  broken. 

Four  Femora,  representing  two  individuals. 

Three  Tibiae,  one  broken,  representing  three  individuals. 

Five  Metacarpals,  representing  four  individuals. 

Four  Metatarsals. 

One  Os  Calcis. 

Two  Astragali,  representing  two  individuals. 

Six  Phalanges — three  pes,  and  three  manus,  including  an  ungulate 
phalanx. 

One  Patella. 

One  Left  Os  Hyoides. 

The  majority  of  these  bones  belonged  to  youthful  individuals. 


More — On  the  Flora  of  Iniah-Bofin.  653 


XLVIII. — ^Kkpoet  on  the  Floila  of  Inish-Bofiw,   Gaiwat.      By 
A.  G.  Moke,  F.L.S.,  M.R.I.A. 

[Bead  April  24,  1876.]  ( 

Havdtg  received  from  the  Academy  a  grant  for  the  examination  of  the 
Flora  of  the  West  of  Ireland,  I  paid,  in  August,  1875,  a  short  visit 
to  the  remote  Island  of  Bofin,  feeling  desirous  to  compare  the  vegeta- 
tion of  another  Atlantic  island  helonging  to  a  different  gecjogical  for- 
mation with  that  of  Aran,  which  latter  has  at  various  times  attracted 
the  notice  of  hotanists,  and  of  whose  Flora  a  tolerably  complete  cata- 
logue* has  been  lately  published  by  my  friend,  Mr.  H.  C.  Hart.  An 
additional  inducement  to  the  choice  of  this  locality  was  that  Mr. 
M'Millan's  recent  discovery  of  the  rare  Helianthemum  guttatum 
seemed  to  promise  some  chance  that  other  rare  plants  might  reward 
the  exploration  of  Inish-Bofin,  especially  as  this  island  has  seldom 
been  visited  by  any  experienced  botanist. 

I  was  accompanied  by  my  friend,  Mr.  R.  M.  Barrington,  whose 
zealous  co-operation  I  cannot  too  gratefully  acknowledge,  and  whose 
untiring  activity  and  botanical  skill  enabled  me  to  accomplish  much 
more  than  I  could  have  done  single-handed.  We  landed  together  on 
the  afternoon  of  Sunday,  the  15th  of  August,  and  left  the  island 
on  the  Friday  following,  having  given  one  day  to  a  cursory  examina- 
tion of  the  adjoining  Island  of  Inish- Shark,  which  we  found  very  un- 
productive in  a  botanical  point  of  view,  as  we  did  not  gather  upon  it 
a  single  plant  not  seen  in  Bofin.  On  Inish-Turk  we  landed  for  a  few 
hours  on  our  way  to  Westport,  and  gathered  twenty  species  which  wo 
had  not  found  in  Bofin.  We  obtained  excellent  quarters  and  a  most 
friendly  reception  in  the  house  of  the  late  Mr.  M*Cormack,  close  to 
the  Harbour  of  Inish-Bofin,  and  in  all  our  excursions,  we  found  a 
most  trustworthy  and  intelligent  companion  in  Sergeant  O'Connor,  of 
the  Royal  Irish  Constabulary,  whose  name  is  already  well  known  as 
the  discoverer  in  Bofin  of  the  gigantic  cuttle-fish,  Architeuthis  dux, 
and  who  proved  himself  a  most  obliging  and  useful  guide  to  all  parts 
of  the  island.  His  local  knowledge  and  influence,  exerted  on  our 
behalf,  in  many  ways  facilitated  our  explorations.  •  \ 

The  Island  of  Bofin,  or  in  Irish,  **Inis-Bo-finne,"  the  Island  of 
the  White  Cow — so  cdled  from  the  legend  of  a  white  cow  which  is 
traditionally  reported  to  rise  at  uncertain  intervals  on  the  surface  of 
the  small  lake  named  Bofin — lies  in  the  Atlantic  Ocean.  ofiF  the  junc- 
tion of  the  two  counties,  Mayo  and  Gal  way,  thirteen  miles  ^cst  from 

•  "  A  Ust  of  plants  found  in  the  Islands  of  Aran,  Gal  way  Bay."  By  H.  C. 
Hart :  Dublin,  1876.  See  also  another  list,  published  by  Professor  E.  P.  Wright, 
in  "  Dublin  Natural  History  Society  Proceedings,  1866." 


654  Proceedings  of  the  Royal  Irish  Academy. 

the  entrance  of  the  Killarj  Harbour,  and  about  six  miles  from  the 
nearest  point  of  the  mainland  of  Connemara.  It  is  about  3j^  miles 
long,  and  2  miles  wide  at  its  greatest  breadth,  containing  an  area  of 
2312  acres  (nearly  four  square  miles),  with  a  population  of  663  in- 
habitants. Inish-Bofiin  was  formerly  attached  to  Mayo,  but  is  now 
included  in  the  county  of  Galway. 

The  geological  formation  belongs  to  the  Lower  Silurian  Schists, 
with  one  narrow  band  of  serpentine  on  the  south-west,  and  a  few  trap- 
dykes  at  Eoyal  Oak  Cave,  and  at  fiunnamullan  Bay. 

There  is  a  fair  extent  of  tillage,  occupied  by  crops  of  potatoes, 
oats,  barley,  rye,  &c.,  also  of  pasture-land ;  but  the  greater  part  of  the 
surface  consists  of  undulating,  hilly  moor,  which  rises  at  a  few  points 
to  nearly  300  feet.  There  are  four  small  lakes,  and  a  few  pools, 
together  with  a  considerable  extent  of  moist  and  boggy  ground,  pro- 
ducing a  fair  proportion  of  water-plants,  sedges,  rushes,  &c.  No  trees 
occur ;  some  alders  and  willows  have  been  planted  here  and  there,  but 
the  few  stunted  bushes  of  blackthorn  and  aspen,  with  scToral  bram- 
bles, represent  the  entire  arboreal  vegetation. 

The  coast  is  almost  everywhere  bounded  by  rocky  clifPs,  with  the 
exception  of  a  small  piece  of  low  sand  at  the  east  end  of  the  island, 
opposite  Inish-Lyon,  and  some  hillocks  of  blown  sand  to  the  south  of 
the  harbour,  which,  however,  do  not  reach  down  to  the  shore  itself. 

The  neighbouring  island  of  Inish-Shark  (581  acres)  lies  close  to 
Inish-Bofiji  at  less  than  a  mile,  and  Inish-Turk  (1445  acres)  five  miles 
to  the  north-east.  Both  these  belong  to  the  same  Silurian  formation, 
and  were  both  visited  by  us,  though  we  had  not  sufficient  time  ta 
examine  them  thoroughly. 

In  the  course  of  four  days  spent  in  Inish-Bofin,  during  which  wo 
were  almost  constantly  at  work,  sometimes  walking  together,  some- 
times taking  different  beats,  we  gathered  altogether  more  than  300 
flowering  plants  and  ferns,  including  several  species  eminently  cha- 
racteristic of  the  west  coast,  and  some  very  rare  or  local  in  Ireland ; 
and  we  succeeded  in  obtaining  the  desired  materials  for  a  very 
interesting  contrast  with  Aran. 

Inish-Bofin  has  seldom  been  visited  by  botanists.  In  August, 
1801,  Dr.  Wade,  then  Professor  of  Botany  to  the  Dublin  Society,  ex- 
plored Galway  under  the  auspices  of  the  Society,  and  in  the  course  of 
his  tour  landed  in  Bofin,  where,  in  his  report,  *  he  records  finding^ 
Arbutus  uva-ursi  (not  seen  by  us),  Artemisia  absinthium  (called 
"common  wormwood"  by  Dr.  Wade,  and  probably  given  by  him  in- 
stead of  A.  vulgaris),  Empetrum  nigrum,  Juniperus  communis,  and 
Asplenium  marinum — a  shortlist,  it  must  be  confessed,  and  one  which 
includes  scarcely  one  of  the  most  remarkable  or  characterisfic  plants. 

Mr.  W.  McMillan,  one  of  the  inspectors  of  National  Schools,  was 


*  "  Catalogus  Plantanim  Rariorum  in  Comitatu  Gallovidioa** — Dublin.  Society's 
Transactions,  vol.  ii.,  part  2,  1802. 


More — On  the  Flora  of  Inish-Bofin.  555 

more  successful  in  1872,  when  he  discovered  Helianthemum  guttatum 
in  its  second  Irish  locality,  and  Euphorbia  hiberna,  in  the  neigh- 
bouring island  of  Inish-Turk. 

Of  the  303  plants  collected  by  Mr.  Barrington  and  myself,  some 
of  the  most  characteristic  are  the  species  which  grow  in  water,  or  are 
attached  to  wet,  heathy,  or  boggy  localities,  and  such  as  I  have 
usually  observed  upon  a  sandy  or  granitic  soil ;  these  will  be  sufficiently 
shown  when  we  come  to  compare  in  detail  the  vegetation  of  Bofin 
with  that  of  Aran. 

If  we  follow  Mr.  H.  C.  Watson's  method  of  grouping,  we  may 
place  under  the 

Atlantic  Type  : 

Saxifraga  umbrosa.  Sedum  anglicum.     A. 

Eriocaulon  septangulare.  Crithmum  maritimura.     A. 

f  Senebiera  didyma.  Pinguicula  lusitanica. 

Helianthemum  guttatum.  Scirpus  Savii.     A. 

Kaphanus  maritimus.     A.  Lastnea  SBmula. 

Only  four  of  these  have  been  observed  in  Aran. 

NoBTHERN  Type  : 

Juniperus  nana.     A.  Pinguicula  vulgaris. 

Isoetes  echinospora.  Empetrum  nigrum. 

Sagina  subulata.     A.?  Sparganium  affine. 

Lobelia  Dortmanna.  Callitriche  hamulata. 

Of  these  last  only  one,  or  at  most  two,  have  been  found  in 
Aran. 

Hence,  we  can  see  how  in  Inish-Bofin  the  western  and  northern 
elements  are  as  strongly  represented  as  in  Aran,  but  by  quite  a  difPe- 
rent  series  of  plants.  The  same  mild  and  equable  climate  produces 
the  same  preponderance  of  the  western  and  northern  types,  and  while 
the  different  soil  ejphibits  the  same  general  results,  the  species  them- 
selves are  different.  In  the  main,  the  Flora  of  Inish-Bofin  agrees 
fairly  with  that  of  the  opposite  coast  of  Mayo  and  Galway,  although 
we  miss  Dabeocia  polifolia,  Vacciniuin  myrtillus,  Viola  Curtisii, 
Drosera  anglica,  Rhynchospora  fusca,  Utricularia  intermedia,  Juncus 
obtusiflorus,  and  a  few  other  species  which  are  common  in  Conne- 
mara. 

That  several  of  the  ordinary  "  colonists  "  and  other  weeds  should 
be  wanting,  is  no  more  than  might  be  expected  in  so  remote  a  locality, 
cut  off  by  the  sea  from  constant  communication  with  the  mainland. 
1^0  poppies,  and  few  of  the  usual  weeds  of  cultivation,  infest  the 
crops ;  but,  at  the  same  time,  it  is  well  worthy  of  remark  that,  judg- 
ing from  the  circumstances  of  growth,  and  their  restricted  localities, 
many  plants,  elsewhere  truly  natives  of  Ireland,  appear  to  have  been 
introduced  into  Bofin. 

B.  I.  A.  FUOC,  SRR.  II.,  VOL.  II.,  80IBNOB.  3  I 


656  Proceedings  of  the  Royal  Irish  Academy. 

In  many  species  we  noticed  an.  unusual  habit  of  growth,  as  in  a 
large-flowered  variety  of  Campanula  rotundifolia,  which  my  friend, 
Professor  Babington,  pronounces  to  be  a  singularly  fine  form,  and  the 
most  remarkable  which  he  has  seen.  Euphrasia  officinalis,  when  on 
the  exposed  grassy  slopes,  grows  with  a  dense  spike  of  firm,  fleshy 
leaves,  and  I  have  observed  the  same  in  Achill.  Matricaria  inodora, 
on  the  wild  rocky  ledges  of  the  cliffs,  oflers  a  handsome  flower  as 
large  as  Chrysanthemum  leucanthemum.  On  the  tops  of  the  gravelly 
hills,  Erica  tetralix,  and  Calluna  vulgaris,  grow  close  to  the  ground, 
with  their  leaves  crowded  on  a  few  short  branches.  Erythraea  cen- 
taurium  scarcely  raises  its  blossoms  above  the  rosette  of  radical  leaves. 
Agrostis  pumila,  and  a  very  dwarf  form  of  Plantago  maritima,  are 
abundant,  and  many  other  examples  might  be  given  of  a  stunted 
habit  of  growth. 

The  rarest  plants  gathered  were : 

Helianthemum  guttatum.  Eriocaulon  septangulare. 

€alamagro8tis  epigejos.  Sparganium  affine. 

Elatine  hexandia.  Isoetes  echinospora. 

Sixteen  are  hitherto  unrecorded,  as  occurring  in  District  YIII.  of 
our  **  Cybele  Hibemica,"  West  Galway,  and  West  Mayo,  viz. : 

f  Fumaria  palHdiflora.  Rubus  villicaul^. 

X  Sinapis  nigra.  f  Arctium  intermedium, 

Polygala  depressa.  *  Salix  Smithiana. 

Elatine  hexandra.  Calamagrostis  epigejos. 

Yicia  angustifolia.  %  Avena  fatua. 

Bubus  discolor.  X  Lolium  temulentimi. 

R.  thyrsoideus.  Glyceria  plicata. 

B.  carpinifolius.  Isoetes  echinospora. 

When  compared  with  that  of  Aran,  which  is  typically  a  limestone 
Plora,  the  vegetation  of  Inish-Bofin  presents  a  striking  contrast,  as 
will  be  best  seen  from  the  following  list,  which  exhibits,  side  by  side, 
the  plants  which  have  been  found  in  one  only  of  the  two  islands. 
The  species  most  characteristic  of  each  formation  are  printed  in  italics. 
The  plants  which  are  not  certainly  native  are  marked  with  the  usual 
signs  of  *,  certainly,  J,  probably,  and  t>  possibly,  introduced ;  and 
the  few  species  which  were  gathered  on  Inish-Turk,  though  not  in 
Bofin  itself,  are  enclosed  in  brackets.  I  have  ventured  to  append  a 
mark  of  suspicion  to  some  of  the  Aran  plants  whose  nativity  was  left 
unchallenged  by  Mr.  Hart,  but  whose  conditions  of  growth  or  distri- 
bution are  such  as  to  give  them  the  appearance  of  doubtful  natives 
in  Aran.  The  abbreviation  "  coL"  (colonist),  indicates  weeds  found 
only  in  cultivated  land,  all  of  which  are  generally  admitted  to  have 
been  originally  sown  with  the  crops  among  which  they  now  grow. 


More — On  the  Flora  of  Imsh-Sqfin. 


657 


COMPAEISON  WITH  ARAN. 


FLAirrs  IN  Abak  kot  fouhd  iir 
Boiw, 


Plakts  in  Bofin  not  eoitnb  nr 
Ab^n. 


Ranimoiiliis  lieterophylliiB. 
Ranunoulus  lingua  P 
t  Aouilegia  vulgaris. 
ThaUetrum  mintu. 


{None  in  Aran,) 


X  Papaver  dubitun  (ool.) 
Glaudum  luteum. 


t  Fmnaria  officinalis  (ooL) 


Cramhe  maritima. 
X  Thlaspi  arvense^Cool . 

[Coohlearia  officinaliB.] 

Cardamine  hinuta. 
*  Hesperis  matronalia. 

MaUhiola  sinoata. 

Arabia  oiliata. 

A.  kirauta. 
^  Barbarea  vnlgaris. 

Nasturtium  palustre. 
t  Erysimum  alliaria. 


Eeseda  luteola. 
X  R.  lutea. 


HeUanthemum  camim. 


Viola  hirta, 
V.  tricolor  P 
y.  CurtisiL 


EanunctUaeea. 

Ranunculus  Baudotii. 


Nifmphaaeea, 

I         Nuphar  luieum, 

Papa/ceraeea, 

(None  in  Bofin») 


Iktmariacea. 

I  X  Fumaria  oonfusa  (ool.) 

Cruet/era. 

t  Senebiera  didyma. 
X  Brassica  napus  (ool.) 
X  Sinapis  arvensis. 


jReiedacea. 


(None  in  Bofin,) 


Cistacea, 

I      HeUanthemum  guUatum» 

Violaeea, 

Viola  canina  (Jlavicornis).   ' 

3IS 


558 


Proceedings  of  the  Boyal  Irish  Academy. 


Plaitts  m  Arak  hot  foukd  iw 
Boiur. 


Plajtts  nr  BoFnr  not  roxjVD  nc 
Abak. 


(Kans  in  Aran.) 


Polygala  vulgaris. 


{None  in  Aran.) 


X  Bilene  inflata  (ool.) 
Bagina  apetala. 
8.  maritima. 
Spergularia  marina. 
Alnne  vema, 
CerasUum  arvense. 


t  Lavatera  arborea. 


Oeranium  lueidum. 
G.  aanguinetim. 
t  Erodium  moschatom. 


{None  in  Aran.) 


Euonymue  europaue. 


Droseracea. 

I      Droeera  rotundifolia. 

Polygalacea. 

I      Polygala  depresea, 

JSlatinacea, 

I      JElatine  hexandra. 

Caryophyllaeea. 

LychnieJhe^cueuH. 
Sagina  eubulaia .  * 
X  Spergula  arveneie  (ool.) 
Spergularia  salina. 
Cerastium  tetrandrum. 

Zinacea. 

I      Eadiola  miUegrana. 

Ifakaeea. 

I 

Hypericacea. 

I      Hypericum  elodes. 

Geraniacea. 


Oxalidaeea. 

I      Oxalis  acetosella. 

Celastracea. 

I  {None  in  Hqfin.) 


*  Sagina  ttrieta  {maritima)  ^  and  not  8,  tubulata,  was  the  plant  gathered  by 
Profeaaor  Oliyer  near  KUropan,  and  this  misquotation  of  ours,  in  the  "Cybele 
^bemica,**  seems  to  haye  nusled  later  observers ;  as  I  hare  always  found  S.  suh^ 
uUUa  decidedly  attached  to  a  sandy  or  granitic  subsoil. 


More — On  the  Fhra  of  Inish-JSqfin. 


559 


Plants  in  Asav  not  found  in 

BOFIN. 


Ithamntu  catharticus. 


TJlex  nanTiB  ? 
i-  Medicago  lupulina. 

Trifolium  prooumbens. 
£tT.  .  .  .  arvense]. 

Lotus  major. 

A»tragalu8  hypogloUU, 


'    Getun  urbanum. 

Fragaria  vesca. 

Rmus  aaxatilis. 

JR,  casius. 

Poterium  sanguisorba. 

Alchemilla  ymgaris. 
i"  A.  arvensis. 
i*  Cratsegua  ozyacantha. 


Epilobinm  hirsutom. 
OircsBa  lutetiana. 


Hippuris  vulgaris. 


iSedum  rbodiolaj 
lotyledon  umbilic 


umbilicuB. 


Saxifraga  b^noides. 
3,  tridactylUes, 


Plants  in  Bofin  not  found  ik 
Aran. 


Ilhamnaeea. 


(None  in  Bofin.) 


Legum%no9M. 

yida  angiutif olia« 


RoBOcea. 


Comarum  paltutre, 
Rubus  discolor. 
R.  thyrsoideos. 
R.  carpinif  olios. 
R.  Tiluoaulis. 


Onagraeea. 

EpUohium  palutire. 


Hahragaeea, 

I      CalUtriche  hamukUa, 

Lythraeea. 

I      PipUa  portula, 

Partulaeea, 

I      Montia  f ontana. 

Crasiulaeea. 


Saxifragaeea. 

Saxifraga  umhrosa* 


560 


Proceedings  of  the  Royal  Irish  Academy. 


Plaitts  nr  Akak  hot  foukd  nr 
Bomr. 


Plabts  nr  Bonir  not  Foinn>  nr 


Sttuenla  eviopea. 
Sryngium  maritmmin> 

•  Smvmium  oluBatrom. 
X  Apiiim  grayeolens. 

HeloBciadium  nodiflomm. 
Pimpinella  ma^na. 
\  ^thusa  oynapium  (ool.) 
Haloeoiaa  Booticum  r 

*  PtuHnaea  $ativa, 
Torilifl  anthriBCUB. 

t  T,  nodosa, 

[AnthriflouB  tylyestris]. 
t  A,  vulgaris. 


ComuM  sanguinea. 


X  Sambuoiu  ebuluft. 
Yiboniam  opuliu. 


RMa  perearina, 
OaUum  whesire, 
O,  horeate, 
X  Bherardia  airensifl  (ool.) 
Aiperuia  cynanchica. 


Yaleriana  officinalis. 
X  Yalerianella  olitoria  (col.) 


CrepiB  Yirens. 
Hieradom  anglicum. 
Carduus  nutans, 

*  Carduus  Marianus. 
C.  tenuiflorus. 
Carlina  vulgaris. 
JSupaioriwn  cannahinum, 

*  Artemisia  absinthiuin. 
Antennaria  dioioa. 
Filago  germanioa. 
Tanaoetum  vulgare. 


UmbeUifem^ 


(Bofin  is  yeiy  poor  in  Umbellif  one.) 


Comaee^. 

I 

Capri/oliacem, 


Rubiacea, 

Oalium  saxatile. 


Vakrianaeea. 


Composiia, 


Tbrinda  hirta. 
Carduus  palustris. 
Senecio  syhaticus. 


More — On  the  Flora  of  Inish-Bofin. 


561 


Flaitts  dt  Akak  not  found  is 
BoFnr. 


[Hex  aquifolimn]. 
X  Frazinus  excelsior. 


Oentiana  verna, 
Chlora  perfoliaia. 


Convolyiiliis  soldonella. 
t  C.  arvensis  (ool  P). 


Solanum  dulcamara. 


SoropliulaTia  nodosa. 
imus. 
Yeronica  serpyllif olia. 


oplii] 
roan 


t   Verbascum  thamus. 


y.  officinalis. 
X  V.  hederifolia  (col.) 


Orobanehe  hedera. 


Lycopos  europeeus. 
t  Mentha  arvensis  (col.) 
t   CalamitUha  offictnalis. 

Ajuga  pyramidalis. 

Ajoga  reptans. 

Btachys  sylvatica. 

Nepeta  glechoma. 
X  Marrubium  Yulgare. 


Plaitts  in  Bopin  not  fottnd  in 
Aban. 


Campanulacea. 


Janone  montana. 
Lobelia  Dortmanna, 


M'icaeea, 

I      Brica  tetralix, 

Aquifoliaeea, 

I 

OUinea. 

I 
Genttanacea. 


CoTwolvulavea. 


SolafMcea. 


Serophulariacea. 


{None  in  Bofin.) 


Scrophnlaria  aquatica. 
Pedicularis  palustris. 
X  Veronica  polita  (col.) 


Orohanehaoea. 

I  {None  in  Bojin.) 

Lahiata. 

ScuteUaria  minor. 


562  Proceedings  of  the  Royal  Irish  Academy. 

Plakts  jot  Abah  not  found  IK      I     Plaj^ts  nr  BoFm  nor  fouitd  dt 

BOFDI. 


Myoflotis  palustriB. 
M.  yersioolor. 
Litho9jtermum  officinale. 
X  Symphytum  officinale. 


[None  in  Aran.) 

[Lyiimaohia  nemomm]. 
Statioe  occidentalis. 


Atriplex  littoralis  ? 
Beta  maritima. 
Suffida  maritima. 
Salicomia  berbacea. 


Rumcx  con^lomeratus. 
Polygonum  liaii. 


X  Euphorbia  peplus  (col.) 
£.  paralias. 
£.  portlandica. 


*  Humulus  lupulus. 
Parietaria  officinalis. 


Quercus  robur. 
rCoryluB  aveilana]. 
*  ropiUus  alba  (planted). 
Saiiz  caprea. 


JBorayinaeea. 

Myoflotis  caMpitoea. 


Pinyuiculaeea. 

Pifwtdcula  vulffaris, 
P.  tu$itanica, 
Utricularia  minor, 

Primulacus, 

I       CentunetduM  minimus, 

Plumhaginacea, 

I 

Chenopodiaesa, 

Atriplex  Babingtonii. 


Polygonaeea, 

•t  Kumex  crispus. 


Empetraeea, 

I      Empctrum  nigrum, 
Euphorbtacea, 


Urticacea, 


Amentifera, 


Populus  tremula. 
Saux  Smithiana. 
S,  aurita. 
Myriea  gale. 


MoBE — On  the  Flora  of  Inish-Bofin, 


663 


Flaitts  in  Aban  not  found  in 

BOFIN. 


Plants  in  Bofin  not  pound  in 
Aban. 


Spiranthes  atstumnali$. 
Orchis  mascuia. 
O.  pyramidaUa, 
O.  cunopsea. 
Maberuiria  viridis. 


*  Narcissus  biflonu. 


Alisma  ranunouloides. 
Trigioohin  maritdmum. 


Aynwi  TjT^^^^TiIa.'piTn- 


Orchidacea. 

Orchis  maculata. 


Amaryllidacea, 

I 

Liliaeea. 

I      Nartheeium  ossifrapum, 

Alismacea. 


Luzula  campestrifl. 


Naiadaeea, 

IPotamogeton  pusillns. 
P.  poiygonifouus. 

Typhaeea, 

I      Sparganium  affine. 

Araeea. 

I 

Eesttaeea. 

I      Eriocaulan  $eptangulare. 

Juncacea, 


Juncns  lamprooarpus. 
J.  supinus. 
J.  oompressus. 
J,  squarro8U9. 
Luzula  muUiflora, 


564 


Proceedings  of  the  Royal  Irish  Academy, 


Plavts  in  Arak  kot  toukd  nr 

BOFIN. 


PuLKTS  nr  BoFnr  kot  fouhd  nr 
Ajulv. 


Cyjperaeea. 


[Sdrpus  lacostris]. 
B.  aetaoeus. 
8.  maritimiu. 


[Cuex  Tulpina]. 


Rhynchospora  alha. 
Eleochahft  paluBtris. 
£.  muUieaiUu, 
Sctrpus  Jhiitan*. 
EriopJutrum  angusUfoUu 
Carex  pulioaris. 
C.  stellulata. 
C.  exteiua. 
C,  binervis, 
C.  panieea, 
C.  pneoox. 
C  anipuilacea. 


Oraminea. 


X  Fhlenm  pratenae. 
P.  arenarium. 
AlopecuruB  genioulatos. 

[Aira  ca^spitosa^. 
Dolerochloa  maritima. 
S.  rigida. 


Ceteraeh  officinarum. 
Poljstichum  angnlare. 
Asplenium  trichomanes. 
Boolopendriam  Yulgare. 
Adianium  captUus-  Veneris, 


AiraJUxuosa. 
X  AveDa  fatna  (ool.) 

Triodia  decambena, 

Koeleria  cristata. 

Poa  trivialiB. 

Festuca  sciuroides. 

F.  elatior. 
X  Lolium  temolentam  (ool.) 

Nardus  stricta. 


Filiees. 


Lastnea  filix-mas. 
X.  efmula, 

A  thyriumJiUx-fixmina, 
Osmunda  regalis. 


Eqidsetum  hyemale  P 


Lyeopodiaeea, 

I      Isoetes  echinospora, 

Equisetacea. 

Equisetum  arvenae. 
£.  limosuiii. 


This  gives  161  plants  peculiar  to  Aran;  92  to  Bofin;  but  if  we 
deduct  the  naturalized  plants  on  both  sides,  we  have  about  120  for 
Aran,  and  80  for  Bofin. 

From  the  above  it  will  be  easily  seen  that  each  formation  has  its 
own  peculiar  plants.  Aran,  which  consists  solely  of  carboniferous 
limestone,  shows  in  a  remarkable  degree  both  the  predominance  of 


MoKB—On  the  Flora  of  Lmh'Bq/in.  565 

lime-loYing  plants,  and  also  the  greater  variety  of  species  whicli  is 
usually  observed  upon  calcareous  soils.  Bofin  exhibits,  as  clearly,  a 
series  of  plants  which  prefer  schistose,  granitic  or  siliceous  soils; 
indeed,  the  only  two  lime-loving  species  which  I  observed  in  Inish- 
Bofin  were  Sinapis  alba  (an  introduced  weed),  and  Asplenium  ruta- 
muraria,  which  grows  upon  the  walls  of  the  ruined  church  of  St. 
Coleman. 

The  only  scarce  plants  common  to  Aran  and  Bofin  are  Calama- 
grostis  epigejos,  a  l^e  native,  and  Allium  Babingtonii,  a  leek  which 
was,  no  doubt,  formerly  cultivated  in  many  ports  of  the  west  of 
Ireland,  as  well  as  in  Cornwall. 

The  three  Aran  Isles,  with  a  much  larger  area  than  Inish-Bofin, 
and  with  a  greater  extent  of  coast  line,  sea-sands,  and  muddy  shore, 
have  hitherto  yielded  372  species,  to  which  we  may,  perhaps,  safely 
add  about  40  more,  which  will  give  an  estimated  total  of  410  for  the 
whole  Aran  group.  Inish-Bofin  itself  reckons  303,  or  with  Inish- 
Turk,  323,  and  in  the  silurian  group  of  Inish-Bofin,  Inish-Shark,  and 
Inish-Turk,  it  is  probable  that  the  whole  number  does  not  exceed 
350. 

With  further  exploration,  the  plants  now  apparently  peculiar  to 
each  group  will,  no  doubt,  be  considerably  reduced,  so  that  instead  of 
221  species  common  to  both,  these  will  probably  be  found  to  be  nearly 
300,  leaving  about  50  plants  peculiar  to  the  three  Isles  of  Bofin,  Shark, 
and  Turk,  and  about  100  to  the  Aran  group. 

This  IB,  indeed,  a  very  striking  difference  between  the  floras  of  two 
groups  of  islands,  situated  under  the  same  conditions  of  climate,  and 
separated  by  a  distance  of  only  thirty-five  miles,  and  shows  very 
plainly  how  much  the  vegetation  is  influenced  by  the  nature  of  the 
subsoil. 


LIST  OF  THE  PLANTS  FOUND  IN  INISH-BOFIN. 

BAinTNCULAOXiB  • 

£anuneuiu8  Baudotiif  Godron. — In  Church  Lake,  and  in  the  small  lake 
called  Lough-na-brand,  on  the  sand-hills  south  of  the  harbour. 

B,  triehophf/iluSf  Chaix. 

B.  hederaceuSf  Linn. — In  many  places,  but  we  did  not  observe  M.  Ze^ 
normandi, 

B.Jhmmulaf  Linn. — Also  y&t,  pseudo-reptanSf  Syme. 

jB.  aeris,  Linn. — {tomophylluB^  Jordan). — Frequent. 

R,  repens,  Linn. 

B.  hulbosusy  Linn. — On  the  sand-hills  south  of  the  harbour. 

'    Ntmphaacejs. 
Nuphar  luteum,  Sm. — ^Plentiful  in  Church  Lake. 


660  Proceedings  of  the  Royal  Irish  Academy. 


I  Fumarta  pallidijlora,  Jord. — Cultivated  ground  near  St.   Coleman's 

Church  or  Abbey. 
I F,  eanfusa,  Jord. — In  several  places,  a  colonist. 

^BrCIFERJE. 

Cakile  marititna,  Scop. — On  the  sands  opposite  Inish-Lyon. 

f  Senehiera  eoronopuSf  Poir. — Common  about  the  harbour,    but  always 

near  houses,  as  if  introduced. 
^  S.  didymay  Sm. — In  several  places  along  the  road  side,  and  among 

rubbish  near  the  harbour. 
f  CapMlla  bursa-pattaris,  D.C. — Waste  places  and  a  weed  in  gardens, 

probably  introduced. 
Cochlearia  danica^  Linn. — Rare. 
C trdamine  praUnais,  Linn. — Common. 
Nasturtium  officinale,  Br. 

f  Sisymbrium  officinale.  Scop. — Chiefly  about  houses. 
J  Brassica  napus,  Linn. — A  colonist  in  cultivated  land. 
X  Sinapis  arvensis,  Linn.  \ 

J  S,  alba,  Linn.  f  All    four    colonists  in    cultivated 

X  S.  nigra.  I     ground,  or  borders  of  fields. 

X  Baphanus  raphanistrum,  Linn.    / 
R,  maritimus,  Sm. — On  the  sands  opposite  Inish-Lyon,  and  a    few 

plants  near  the  harbour. 

CiSTACEJI. 

Helianthemum  guttatum,  Mill  (var.  Breweri,  Planch). — Plentiful  in 
many  places,  especially  on  high  ground,  both  in  Bofin  and  Shark, 
but  we  did  not  observe  it  on  Inish-Turk. 

ViOLACILfi. 

Viola  palustris,  Linn. — Frequent. 
F.  sykatica.  Fries. — Shady  banks. 

F.  canina,  Linn,  {flavicomis,  Sm.). — Stony  or  heathy  margins  of  the 
lakes  in  several  places. 

Droseracsjs. 

Drosera  rotundifolia,  Linn. — Frequent. 

POLYGAXACEiE. 

Polygdla  depressa,  Wender. — ^This  was  the  only  form  found,  well 
marked  by  the  crowded  oval  leaves. 


More — On  the  Flora  of  Inish-Bofin.  567 


Elatinace^. 

Elatine  hexandra,  D.C. — In  shallow  water  on  the  gravelly  bottom  of 
Lough  Gowlanagower,  Lough-na-grooaun,  and  Lough  Fawna, 
abundantly. 

CAETOPHTLLACEiE. 

SiUne  maritima,  With. — Not  common. 

Lychnis  floB'CUCuU,  Linn. — Only  near  Church  Lake. 

Honekenya  peploides,  Epr. — Sands  opposite  Inish-Lyon. 

Sagina  procumbens,  Linn. 

8.  suhulatay  Wimm. — In  one  place  only,  at  south  side  of  the  island. 

S,  nodosa,  Mey. — Damp   rocky  ledges  near  St.   Coleman's    Church 

or  Abbey. 
J  Spergula  arvensis,  Linn. — A  weed  in  cultivated  land.     Both  forms, 

S.  arv&nsis  (Reich.)  and  S.  vulgaris  (Boiinng.),  occurred,  and 

most  of  the  specimens  which    we   examined  belonged  to  the 

former. 
Sp&rgularia  rupicola,  Lebel. — About  the  cliffs  at  west  end  of  Bofin, 

in  many  places. 
8.  salina,  Prcst. — On  damp  ground  at  foot  of  the  cliffs  in  south-west 

of  the  island. 
Armaria  serpylUfolia,  Linn. — Typical  form  only. 
Stellaria  mediae  With. 
Cerastium  ghmeratum,  Thuill.     \ 
C,  triviale.  Link.  >  All  three  frequent. 

C,  Utrandrum^  Curt.  ) 

Ldtace^. 

Zinum  eatharticum,  Linn. — In  many  places. 
Radiola  millegrana,  Sm. — Plentiful. 

Malvacejs. 

f  Maka  sykestris,  Linn. — ^Near  the  harbour  and  about  the  village. 
A  variety  with  leaves  deeply  angulated  and  their  base  wedge- 
shaped,  instead  of  cordate,  was  gathered. 

Htpebicacks. 

Hyperieum  androsamum,  linn. — On  rocks  near  Church  Lake. 
JJ.  quadrangidum  (tetrapierum,  Fries). — Frequent. 
JST,  humifusum,  Linn. 
S,  pulchrunij  Linn. 
jET.  elodeSy  Linn. 


568  Proceedings  of  the  Royal  Irish  Academy. 


Oebakiicejs. 

Erodium  cicuUirium,  Sm. — Shady  places,  frequent. 
Geranium  molle^  Linn. — Rocks  near  Church  Lake, 
j-  G.  diMectum^  Linn. — ^Waste  and  cultivated  ground,  rare. 
G.  Rohertianum^  Linn. 

YBT,  purpureum,  Forst. — On  heaps   of  stones  near  the  old  min 
of  St.  Coleman's  Church. 

OXALm^CEJI. 

Oxalii  aeetouUay  Linn. — Near  Church  Lake. 

Leoujcikosjb. 
AnthyUii  vtdneraria,  Linn, 
f  Trtfolium  repens^  Linn.    \ 

I  T.  pratefue,  Linn.  )  All  three  probahly  introduced, 

t  T.  minus,  Relh.  ) 

Lotus  eomiculatus,  Linn. — In  many  places. 

Vicia  cracca,  Linn. 

V.  sativa.     Var.  J  segetalisy  Thuil. — In  stubbles  and  along  hedges  or 
borders  of  fields,  probably  the  remains  of  former  cultivation. 

V,  angustifoliay  Roth. — Sandy  ground,  eastward  of  the  village. 

V,  Bepium,  Linn. — Shady  banks  and  bushy  places. 
Zathynu  pratensis,  Linn. — Shores  of  harbour. 

ROSACKB. 

Prunus  spinosa,  Linn. — ^Grassy  banks  on  the  east  side  of  the  harbour, 

very  sparingly. 
Spirma  ulmaria,  Linn. 
Potentilla  anserinay  Linn. 
P.  reptanSf  Linn. — Rather  rare. 
P,  tormentilla,  Linn. — Both  typical,  and  also  the  variety  or  hybrid, 

P.  procumbenSf  Sibth. 
ComaruM  palustrSy  Linn. 
Rubus  discolor^  W.  et  N. 
R,  tkyrsoideuSy  Wimm. 
R.  carpinifoliuSy  W.  et  N. 
R.  villicaulis,  W.  et  N. 

These  four  brambles  were  all  gathered  on  the  east  side  of  the  vil- 
lage and  about  Church  Lake.  I  am  much  indebted  to  my  kind  friend 
Professor  C.  C.  Babington,  who  was  good  enough  to  take  the  trouble 
to  examine  the  specimens  which  I  collected,  and  who  has  thus  approx- 
imately determined  their  names,  though  from  their  incompleteness 
the  specimens  were  not  quite  sufficient  for  certainty. 
Rosa  spinosissima,  Linn. — In  several  places. 


More— On  the  Flora  of  Inish-Bofin.  569 

H.  eaninaf  Linn. — Bare ;  east  side  of  the  harbour  only. 
•fAarimonia  eupatoria,  Linn.  —Rare  ;  roadside  towards  Church  Lake. 
(R.  M.  B.) 

Onaokacejb. 

!Epilohxum  pwrviflorum,  Schreb.   \ 

E,  montanum,  Linn.  >  All  three  frequent. 

E.  palmtre,  Linn.  ) 

JS,  tetragonum,  Linn. — Only  the  form  obicurum,  3chreb. 

HALOKAGACEiB. 

Myriophyllum  altem\florumy  D.  C. — Frequent. 

Callitriche  vema,  Linn. 

C  platycarpa,  Kutz. — On  muddy  borders  of  streams. 

C,  kamulata,  Kutz. — Frequent,    and  a  plant  very  characteristic  of 

mountain  lakes.     A  small  form,  with  very  narrow  leaves,  grows 

in  Lough  Gowlanagower. 

JjTTBiULCEM, 

Zy thrum  salicaria^  Linn. — In  many  places. 
FepliB  portula,  Linn. — Frequent. 

PoKTULACKfi. 

Jfontia  fontanaf  Linn. — Common. 

CRASSULACEiB. 

JSedum  anffh'eum,  Linn. — Frequent,  and  of  very  large  size,  on  stone 

fences  round  the  harbour. 
JS.  acre,  Linn. 

Saxifragaceje. 

JS.  umhrosa,  Linn. — On  the  rocks  south  of  Church  Lake,  and  found 
also  on  Inish-Turk.  As  in  Achill,  and  I  believe  throughout  Con- 
nemara,  the  prevailing:,  if  not  the  only,  form  is  serrati/olia.  Our 
guide  in  Inish-Turk  called  it  the  **  Leaf"  (not  Cabbage)  "  of  St. 
Patrick." 

Araliacejs. 

Sedera  helixj  Linn. — Frequent  on  the  cliffs,  &c. 

Umbellife&2b. 

Mffdrocotyle  vulgaris^  Linn. — Plentiful. 

^  Conium  maculatumy  Linn. — About  the  harbour  and  near  houses 
along  roadsides,  on  rubbish,  probably  introduced. 


570  Proceedings  of  the  Royal  Irish  Academy, 

Heloseiadium  inundatum^  Koch. — In  several  places,  and  found  also  in 

Inish-Shark. 
Crithmum  maritimum,  Linn. — Plentiful  along  the  south-west  shore. 
Angelica  f^ylvestriSy  Linn. — On  damp  ledges  of  the  clifPs ;  also  in  Inish- 

Turk,  where  it  is  fully  exposed  to  the  Atlantic  gales. 
X  Heracleum  aphondylium,  Linn. — Observed  only  on  the  grassy  lawn  of 

Mr.  M'Cormack's  garden,  where  it  was,  in  all  probability,  sown 

unintentionally. 
Daucu8  carota,  Linn. — Bocks,  banks,  and  pastures ;  frequent. 

CAFRIFOLIACEiB. 

*  Samhucus  nigra,  Linn. — A  few  shrubs  only,  and  evidently  planted,. 

near  some  cottages  in  the  centre  of  the  island. 
Zonicera  periclymenum,  Linn. — About  Church  Lake,  &c. 

RlTBIACE^. 

Galium  verum,  Linn. 

G.palustre,  Linn. — Chiefly  as  the  most  usual  form  called  G.    Wither- 

ingiiy  but  a  few  robust  plants  in  the  marshy  borders  of  Church 

Lake  are  nearer  to  G.  elangatum,  Presl. 
G.  saxatilc,  Linn. — In  many  places,  and  a  very  characteristic  species. 

*  G.  apariney   Linn. — Only  in  and  about  cultivated  land,  no  doubt 

intioduced. 

DiPSACACEJE. 

Scahiosa  succisay  Linn. 

CoMPOSITiE. 

Thrineia  hirta.  Roth. 

Oporinia  autumnalis,  Don. 

Hypochceris  radicata,  Linn. 

X  Sonchus  arvensisy  Linn. — A  colonist  among  the  crops. 

t  S.  a»per,  Hoffra.    »  g^^^         jy    i^t^oj^,^ 

T  o.  oleracen^y  Lmn.  S  ^  ^ 

Hieracium  pilosellay  Linn. — Near  St.  Coleman's  Church. 

t  Taraxacum  officinale^  Wigg. — Perhaps  introduced. 

X  Lapsana  cominunisj  Linn. — A  colonist. 

t  Arctium  lappa  {intermedium,  Lange). — This  was,  as  in  other  parts 

of  Ireland,  the  only  form  seen, 
f  Carduus  lanreolatuSj  Linn. 
C^  palustris,  Linn. 

t  C,  arvensis,  Curt. — Rather  rare,  and  perhaps  introduced. 
Centaurea  nigra,  Linn, 
f  S.  scahiosa,  Linn. — Only  on  the  sand-hills  among  the  rabbit  biurows, 

and  perhaps  introduced. 
X  Artemisia  vulgaris^  Linn. — Borders  of  fields,  waste  places,  and  in 

cultivated  land.     Now  apparently  a  colonist,  whatever  its  origin. 

A.  absinthium  was  not  observed,  and  probably  Dr.  "Wade  entered 

the  wrong  species  in  his  list. 


More — On  the  Flora  of  InUh-Bofin.  571 

Gnaphalium  ultpnosum,  lion. 

Tussilagio  farfaraf  Linn. 

Aster  tripolium,  Linn. — On  the  south-west  shore. 

Solidago  virgaurea,  Linn. 

f  Senecio  vulgaris,  Linn. — Perhaps  introduced. 

8,  sylvaticusj  Linn. 

8,  Jacohaa,  Linn. — On  the  sand-hills  south  of  the  harbour  we  found  a 
variety  with  the  Hgulate  florets  much  broader  and  shorter  than 
usual,  giving  the  flower  an  appearance  something  like  a  Cine- 
raria.    The  rayless  form  did  not  occur. 

8.  aquaticuSy  Huds. 

Inula  dysenterica,  Linn. — Near  St.  Coleman's  Church, 

•f  Bellis  perennts,  Linn. — Possibly  introduced. 

J  Chrysanthemum  segetum,  Linn. — A  weed  in  the  crops. 

C.  leucanth^mum,  Linn. — Eare. 

Matricaria  inodoraj  Linn. — A  fine  variety,  with  large  and  conspicuous 
flowers ;  grows  on  rocky  ledges  of  the  clifPs,  both  in  Bofin  and  in 
Achill. 

Achillea  ptarmica,  Linn. 

A.  millefolium,  Linn. 

CAMFAirrLACKi:. 

Campanula  rotundifolia,  Linn. ;  var.  speciosa. — A  large-flowered  and 
very  handsome  variety  grows  among  the  rabbit  burrows  south  of 
the  harbour.  "  The  stems  are  from  nine  to  twenty  inches  high, 
the  leaves  broader  and  more  crowded  than  usual,  lanceolate  and 
Hnear-lanceolate  on  the  middle  of  the  stem.  Flowers  from  one 
to  twelve,  with  a  corolla  at  least  an  inch  long.  This  plant,  in 
some  of  its  characters,  comes  near  to  the  variety  arctica,  figured 
in  **  Flora  Danica,"  XVI.,  Tab.  2711,  but  has  much  larger 
flowers.  It  also  agrees  to  some;  extent  with  a  var.  lancifolia, 
described  in  Hartman's  "  Skandinaviens  Flora,"  but  the  stem  is 
not  recumbent.  Being  apparently  distinct  from  any  described 
variety,  I  believe  this  beautiful  plant  quite  deserves  a  separate 
name,  as  var.  speciosa,  which  I  here  propose  for  it. 

Jasione  montana,  Linn. — Plentifid,  and  one  of  the  most  characteristic 
species. 

Lobelia  Dortmanna,  Linn. — Plentiful  in  Lough-na-grooaun ;  very  rare 
in  Lough  Gowlanagower. 

Ebicace^b. 

JErica  tetralix,  Linn. — Common  even  on  the  tops  of  the  barren  stony 
hills,  where  it  assumes  a  dwarf,  stunted  habit,  offering  only  two 
or  three  branches,  on  which  the  leaves  are  densely  crowded. 

a,  einerea,  Linn. — ^Plentiful. 

Calluna  vulgaris,  Salisb. — In  exposed  stony  places  it  occurs  quite 
stunted,  and  with  leaves  crowded  in  the  same  way  as  in  J*,  tetralix, 

B.I.A.  PBGC,  SSa.  U.,  VOIi.  U.,  SCUZfCB.  3  K 


572  Proceedings  of  the  Royal  Irish  Academy. 


Gbhtiakacea. 

Oentiana  eampestris,  Linn. — ^Frequent,  and  of  large  size.      A  Tarietj 

with  white  flowers  also  occurred. 
Erythraa  eentaurium,  Pers. — Chiefly  in  the  form  with  broad  radical 

leaves,  and  little  or  no  stem,  which  has  often  been  miacalled  *^£. 

littoralisV 
Jfenyanihet  tri/oliaia,  Linn. — Church  Lake. 

CONTOLTCLACK^. 

Ctmvokulut  tepium,  Linn. — Frequent  in  bushy  places  and  on  fences, 
and  nearly  always  with  pink  flowers. 

SCROPHULABIACEJE. 

rW'Ofitra  arvefuiSf  Linn. 

V.  anagallin,  Linn. — Streamsidc  near  St.  Coleman's  Church. 

Fl  heccahunya,  Linn. 

F.  ehanuedrysy  Linn. 

f  V.  ayrestis,  Linn.        )  Cultivated  land  and  roadsides ;  probably  in- 

f  V,  polita^  Fries.  )      troduced. 

f  BarUia  odontites,  Huds. — All  the  plants  which  we  observed  belonged 
to  the  form  U,  serotina,  Reich ;  perhaps  a  colonist  only. 

Euphrasia  officinalis ,  Linn. — ^Both  the  typical  form  and  JE.  yracilis, 
Fries,  the  latter  rather  more  frequent  of  the  two.  Also  a  mari- 
time variety  with  stiff  fleshy  broad  leaves,  and  bracts  closely 
crowded ;  a  form  which  I  have  also  noticed  in  Achill. 

Rhinanthus  erista-yaUi,  Linn.  « 

Pedieularis  palustriSf  Linn. — Bare,  near  Church  Lake. 

P.  nyhatica,  Linn.— Frequent. 

Serophularia  aquatica,  Linn. — ^Eare,  observed  in  one  place  onl j,  east  of 
the  village. 

Labiatjs. 

Mentha  aquatica,  Linn. — ^Frequent. 

Thymus  serpyllumy  Linn. 

Teucrium  seorodonia,  Linn. 

J  Lamium  purpureum,  Linn. — A  weed  in  gardens,  etc. 

f  Oaleopsis  tetrahit,  Linn. — On  rubbish,  and  in  borders  of  fields  about 

the  village,  probably  introduced. 
Stachys  palustris,  Linn. 

J  iS.  arvtfnsis,  Linn. — Cultivated  ground,  a  colonist. 
Prunella  vulgaris,  Linn. 
Scutellaria  minor,  Linn. — Near  Church  Lake. 


More — On  the  Flora  of  Inkh^Bofin.  573 


Myo9ot%B  e(B9p%toBaj  Schultz. — Frequent. 
M:  arvensis,  Hoffm. 

PiNOUICUIJLCEJS. 

Pinguicttla  vulgaris y  Linn. — Frequent. 

jP.  lusttanica,  Linn. — Rather  rare. 

Utricularia  minor,  Linn. — ^At  west  end  of  the  island,  in  one  place  only. 

PRDTOLACE^. 

I^rimtda  vulgaris^  Huds. — Near  Church  Lake ;  a  few  plants  flowering 

so  late  as  August  19th. 
J  Anagallia  arveruis,  Linn. — A  colonist  probably. 
A.  tenella,  Linn. 
Centunculua  minimus,  Linn. — Not  common^  but  found  at  both  east  and 

west  ends  of  the  island. 
Samolus  Valerandi,  Linn. — ^Frequent. 
•Olauz  maritima,  Linn. 

Plxtmbagivacks. 

Armeria  mariiima,  Willd. — Frequent. 

Plaktaginaceje. 

-f  Plantago  major,  Linn. — About  Church  Lake,  &c. ;  not  common,  and 

probably  introduced, 
f  P.  laneeolata,  Linn. — Perhaps  introduced. 
P,  mariiima,  Linn. — Common,  and  a  dwarf  form  is  abundant  all  over 

the  tops  of  the  hills. 
P,  coronopus,  Linn. — Frequent. 
LittoreUa  lacustris,  Linn. — ^Borders  of  Lough  Fawna,  &c. 

CHENOPOniACKaE. 

X  Chenopodium  album,  Linn. — Both  varieties  :  C,  eandieans,  Linn ;  and 

C.  viride,  Linn. 
Atriplex  Babingionii,  Woods. — Common  about  the  harbour,  &c. 
A.  patula,   Linn. — The  vars.    angustifolia   and   jereeta  were  both 

frequent.     The  last  occurs  only  in  cultivated  ground,  as  if  a 

colonist. 
Sdlsola  Kali,  Linn. — Sands  opposite  Inish-Lyon. 

POLYOONACE-B. 

Polygonum  amphihium,  Linn. — In  the  small  lake  in  the  sand-hills,  colled 
Lough-na-brand,  and  here  the  terrestrial  form  was  flowering 
freely. 

3  E  2 


674  Pro€eediug$  of  the  Royal  Irish  Academy. 

P.  periicartat  Linn.       \ 

P.  hydropiper,  Linn.      J  .Vll  three  frequent. 

P,  avieulare,  Linn.        ) 

f  P.  conrolvMlu$f  Linn. — A  weed  in  coltiyated  land  and  borders  of 

fields, 
t  Rumex  erupuif  Linn. — Frequent,  but  perhaps  not  native, 
t  R.  ohtu9ifoUu9,  Linn. — Like  the  jformer,  perhaps  introduced. 
R.  acetosa,  Linn. — Not  uncommon. 
R.  acetosella,  Linn. — Ditto. 

Oh$, — ^Wc  could  not  find  R.  tanyuineut  nor  R.  ecnghmerakiu. 

Empetkaceje. 

Empetrum  niyrumt  Linn. — ^Very  rare ;  observed  only  in  one  place  near 
a  blowhole  west  of  Moylanboy  Bay  (B.  M.  B.)  Also  on  Inish- 
Turk. 

EUPHORBIACE^. 

I  Euphorbia  heliotcopiaf  Linn. — Among  crops ;  rare. 

Ubticace-ts. 

*  Urtiea  urenn^  Linn.   |  "Waysides  and  waste  places ;  both  no  doubt  in- 

*  U.  dioica^  Linn.         )  troduccd. 

Ahentifer^. 

Poptdut  tremula,  Linn. — Sparingly  on  rocky  banks  at  east  end  of  tlu 
harbour.     Also  on  Inish-Turk. 

*  Salix  viminalisy  Linn.     )  -d  xv  •  x    j  <    a 
^  o    o    -ji  •         w-n^       I  Both  introdiiced. 

*  o.  Smtihtanaf  WiUd.      ) 

8.  auritat  Linn. — The  only  sallow  observed. 
8.  repenif  Linn. — Frequent. 

Myrica  Oaky  Linn.— Plentiful  in  one  locality  only,  near  Bunnamull en 
Bay.    (R.  M.B.) 

CoioFSiLas. 
Juniperua  community  Linn. — Only  the  form  or  variety,  J.  nana y  WilU^ 

OsCHIDACKfi. 

Orchis  mactdata,  Linn. — Hather  rare,  near  Church  Lake. 

Ibidace^. 
Iris  piCHdacorus,  Linn. — Near  Church  Lake,  &c. 


More —  On  the  Flora  of  In  Uh-Bofin,  575 


LlUACEiE. 

"*  Allium  jBabtngtoniif  Borr. — Among  the  ruins  of  a  deserted  cottage, 
east  of  the  harbour  (K.  M.  B.)  Also  in  a  garden  enclosure  close 
to  a  cottage,  to  the  south  of  Lough  Gowlanagower ;  several  of  the 
heads  viviparous.  This  is,  no  doubt,  a  relic  of  former  cultivation, 
as  it  appears  also  to  be  in  all  the  other  localities,  wherever  I  have 
seen  it  in  the  West  of  Ireland.  At  Eoundstone  it  occurs  only 
along  the  borders  of  garden  enclosures.  On  the  south  side  of 
Clew  Bay,  and  near  Menlough,  Galway,  always  about  the  ruins 
of  cottages  or  deserted  gardens. 

Narthecium  omfragwn^  Huds. — At  west  end  of  the  island. 

AxiSMACiLS. 

TViglochin  palustre,  Linn. — Along  the  south-west  shore. 

Naiadace^. 

Potamogeton  peciinatuSf  Linn. — North  end. of  Lough  Bofin. 
jP.  pusiUuSf  Linn. — In  Church  Lake. 

jP.  natansy  Linn. — ^Very  fine  and  plentiful  on  Lough-na-grooaun. 
P.  polygonifoliui,  Pourr. — Common  in  damp  boggy  places. 
Zostera  marina^  Linn. — In  the  harbour. 

Lehnacejb.   • 
Zemna  minor j  Linn. — ^Frequent  in  pools  and  slow  streams. 

Typhace^. 

Sparganium  affine,  Schn. — Plentiful  in  Lough  Gowlanagower  and  Lough- 
na-grooaun. 

EESTIACEiB. 

Erioeatdon  septangidarej  With. — Several  large  patches  along  the  west 
side  of  Lough-na-grooaun. 

JUNCACKX. 

JuneuB  communis,  Mey. — Both  forms,  eonghmeratus  and  effmus,  were 
observed. 

J,  aeutiflorusy  Ehrh. — Frequent. 

J,  lamprocarpuSf  Ehrh. — Frequent. 

J,  supinus,  Moench. — Plentiful,  and  the  submerged  variety,  with  seta- 
ceous leaveS)  is  abundant  in  most  of  the  lakes. 

-/.  compresBw,  Jacq. ;  var.  G&rardi,  Lois. — ^Alongthe  south-west  shore. 


676  Proceedings  of  the  Royal  Irish  Academy. 

J.  hufoniuSf  Linn. — Common. 

J.  squarroius,  Linn. — Hilly  ground  at  west  end  of  the  island. 

Zmula  mtUtiflora,  Lej. — L.  campestrU  was  not  seen. 

Cyperacks. 

Sehcenus  niyrieans,  Linn. — Above  Bunnamullen  Bay,    with   Myrica 

(R.  M.  B.)     Also  on  Inish-Turk. 
Ithynchospora  alba,  Vahl. — Rare.     At  Bunnamullen  Bay,  and  at  west 

end  of  Bofin. 
Seirpus  Savii^  8.  et  M. — Frequent. 

S.Jluitans,  Linn. — Frequent,  and  a  very  characteristic  species. 
EUochari%  paltutriSf  Br. — Church  Lake,  &c. 
£.  multicaulis,  Sm. — Plentiful  and  characteristic. 
£riophorum  anyuatifolium.  Roth. — Frequent.  , 
Carex  pulicaHs,  Linn. — Near  Church  Lake,  &c. 
C.  ttellulatafGood. — Abundant. 
C.  arenanaf  Linn. 

CflavOf  var.  lepidocarpa,  Tausch. — Common. 
C.  externa f  Good. — South-west  shore. 
C  distanSf  Linn. — South-west  shore. 
C.  hinerviSf  Sm. — West  end  of  the  island. 
C,  panicea,  Linn. — Frequent. 
C.  ylaucdf  Scop. — Common. 
C.  pracox,  Jacq. 
C  ampullacea.  Good. — Church  Lake. 

Graminils. 

Anthoxanthum  odoraium^  Linn. 

Ayroetis  caninay  Linn. 

A.  vulyariif  With. 

var.  pumila,  Lightf . — Frequent  on  the  higher  parts  of  the  hills. 

A,  alhaf  Linn. — Common,  with  many  varieties. 

Psamma  arenaHa,  R.  et  S. 

Phragmites  communis^  Trin. 

Calamagrostis  eptgejos,  Roth. — Sparingly  on  rocky  banks  at  east  end 
of  the  inner  harbour.  It  is  curious  to  find  both  in  Bofin  and 
Aran,  two  isolated  localities,  for  a  grass  which  is  so  rare  in  Ire- 
land. 

Airaflexuosa,  Linn. 

A,  carytyphyllea^  Linn. 

A.  pracoXf  Linn. 

X  Avena/atua,  Linn. — A  weed  in  the  com  crops  of  Bofin  and  Inish- 
Shark. 

f  Arrhenatherum  avenaceum,  Bcauv. — Perhaps  introduced,  but  now  an 
abundant  weed. 

IToleus  lanatus,  Linn. 


More— On  the  Flora  of  Inish-Bofin.  577 

Triodia  decumhen8\  Bcauv. 

Koeleria  crutata^  Pers. — ^Banks  opposite  Iiiish-Lyon,  &c. 

Jfolinia  earulea,  Mocnch. 

Glyceria  fluitanSj  Br. — Common. 

G.  plicata,  Fries. — Rare ;  in  one  place  only. 

ScUrochloa  loliaceaf  Woods. 

J^oa  annua,  Linn. 

P.  praUnsis,  Linn. 

f  P.  trivialisy  Linn. — ^Possibly  introduced. 

Cynosurus  cristatuSy  Linn. 

Dactyl%9  glomerata,  Linn. 

t  Fe$ttica  sciuroideSf  Both. — ^Very  rare  on  banks^  and  probably  not 

native. 
F.  ovina,  Linn. 
F.  duriuscula,  Linn. 
F.  ruhra,  var.  $abult'eola,  Buf . 
F.  elatior,  Linn. — Also  on  Inish-Turk. 
F,  pratenaiSy  Huds. 
Bromus  mollis,  Linn. 

var.  mbglaber.  Sands. — On  the  sea-shore. 
Braehypodium  sylvaticum,  Beanv. — East  of  harbour,  &c. 
Triticum  repens,  Linn. 

T.  junceum,  Linn. — Sands  opposite  Inish-Lyon. 
Lolium  perenne,  Linn. 

%  Z.  temulentuniy  Linn. — A  weed  among  com. 
Nardiu  atricta,  Linn. — Frequent. 

FiLICES. 

Polypodium  vulyare,  Linn.    \ 

Lastraa  filix-masy  Presl.       |  Frequent. 

Z.  dilatata,  Presl.  ) 

Z.  amula,  Brack. — Rare,  only  near  Lough  Fawna  (R.M.B.)     On  the 

west  side  of  Inish-Turk  (A.G.M.) 
AthyriumJUix-fmmina,  Roth. — Frequent.     A  variety  found  among  the 

rocks  near  Church  Lake  has  a  frond  broader  than  usual,  with 

wide  ovate  pinnules,  resembling  those  of  Lastraa  dilatata, 
AspUnium  marinumy  Linn. — Abundant  in  many  parts  of  the  cliffs. 
A,  adiantutn-niyrum,   Linn. — In    its  typical  form,   and    lio    plants 

approaching  A.  aeutum,  Bory. 
A.  ruta-muraria,  Linn. — On  the  ruins  of  St.  Coleman's  Church. 
Blechnum  horeaUy  Sw. — Not  uncommon. 
Pteris  aquilina,  Linn. 
Osmunda  reyalis,  Linn. — Frequent. 

Lycopodiacks. 

lioetes  echinospora,  Dur. — ^In  Lough  Qowla-na-gower  and  Lough-na- 
grooaun. 


678  Proceedings  of  the  Royal  Irish  Academy. 

Equisetum  arvenw,  Liiin. 
jK.  Umosum^  Linn. 


To  these  should  be  added  20  other  plants  gathered  by  ns  on  Inish- 
Turk,  an  island  belonging  to  the  same  silurian  formation,  and  which 
lies  five  miles  north  of  Inish-Bofin.  Those  found  in  Aran  are 
marked  A. 

Cochlearta  officinalis,  A.                  Corylus  arellana,    A. 

Lychnis  diurna.  Betula  aWa. 

t  Tri/oUum  arvense,     A.  Saiix  einerea, 

Orobus  tuberosus.  Scirpus  lacustris.     A. 

Sedum  rkodiola.     A.  Carex  dioica. 

(Enanthe  crocata.  C,  rufpina.    A. 

Anthriscus  sylvestris,  A.                  C.  paniculata. 

Hex  aquifolium,     A.  C  vulgaris. 

Lysimarhia  nemorum,  A.                 Aira  C€tspitosa,     A. 

Euphorbia  hyberna.  Orchis  incamata  f 

This  will  make  a  total  of  323  species  on  the  three  Islands  of  Inish- 
Bofin,  Inish- Shark,  and  Inish-Turk — a  number  which  further  investi- 
gation will  probably  raise  to  350. 


Davy — On  a  New  Chemical  Teat  for  Alcohol,  579 


XLIX. — Ox  A  New  Chemical  Test  fob  Alcohol.  By  EDMUin)  W. 
DaVy,  A.m.,  M.D.,  Professor  of  Porensic  Medicine,  Eoyal  College 
of  Surgeons,  Ireland,  &c. 

[Bead  May  22,  1876.] 

"Whilst  making  lately  some  experiments  on  molybdic  acid,  I  observed 
that  when  a  solution  of  that  substance  in  strong  sulphuric  acid  was 
brought  in  contact  with  alcohol,  there  is  very  quickly  developed  a 
deep  azure  blue  colouration ;  and  this  fact,  being  (as  far  as  I  was  able 
to  ascertain)  hitherto  unrecorded,  led  me  to  investigate  the  reaction  to 
determine  the  cause  of  this  production  of  colour. 

As  I  found  that  the  protosulphate  of  iron,  and  the  protochlorido 
of  tin,  two  powerful  deoxidizing  salts,  produced  a  similar  effect  on 
this  solution,  there  was  but  little  doubt  that  it  was  due  to  the  deoxi- 
dizing action  of  alcohol  on  the  molybdic  acid.  And  I  afterwards 
found  that  the  blue  substance  which  was  formed  in  the  case  of  alcohol 
possessed  all  the  characters  of  the  blue  compound  which  is  produced 
when  molybdic  acid  or  its  salts  are  acted  on  by  different  reducing 
agents,  whereby  a  substance  consisting  of  five  atoms  of  the  metal 
molybdenum  with  fourteen  of  oxygen  is  obtained,  which  is  usually 
regarded  as  a  combination  of  the  binoxide  of  molybdenum  with  molyb- 
dic acid,  the  following  formula  (M0O2,  4  M0O3)  representing  its 
composition. 

With  certain  precautions  which  I  shall  presently  point  out,  I  have 
found  that  this  reaction  of  alcohol  on  the  molybdic  solution  stated  is 
extremely  sensitive,  so  that  by  its  indications  very  minute  quantities 
of  alcohol,  even  when  diluted  with  large  proportions  of  water,  may  be 
readily  detected.  Thus,  for  example,  if  one  part  by  volume  of  com- 
mercial rectified  spirits  be  mixed  with  a  hundred  parts  of  distilled 
water,  and  one  small  drop  of  this  mixture  be  taken,  the  minute 
quantity  of  spirit  contained  in  it  can  bo  easily  detected  by  the  deep 
blue  colouration  which  will  be  immediately  developed  on  bringing  it 
into  contact  with  the  molybdic  solution,  employed  in  the  manner  about 
to  be  desciibtHl.  13ut  tlus  is  not  the  limit  of  the  delicacy  of  this  test, 
for  I  have  been  able  by  means  of  it  to  detect  the  spirit  in  one  drop  of 
a  mixture  of  distilled  water  and  anhydrous  spirit,  in  which  the  latter 
substance  constituted  only  the  one-thousandth  part  of  its  volume; 
and  as  the  drop  was  found  to  weigh  six-tenths  of  a  grain,  the  quantity 
of  real  or  anhydrous  alcohol  contained  in  it  would  be  less  than  the  one- 
fiixteen  hundred  and  sixty-sixth  part  of  a  grain  of  that  substance. 

Though  small  quantities  of  spirit,  even  when  considerably  diluted 
with  water,  will  produce  with  the  molybdic  solution  the  blue  reaction 
without  the  assistance}  of  any  external  heat,  still  where  very  minute 
quantities,  diluted  with  such  large  proportions  of  water  as  those  just 
stated,  are  to  bo  detected,  it  is  necessary  for  the  success  of  the  experi- 
ment that  .the  reaction  should  be  assisted  by  a  gentle  heat,  and  also 


580  Proceedings  of  the  Royal  Irish  Academy. 

that  too  great  a  dilution  of  the  test  solution  with  the  liquid  under 
examination  should  he  avoided,  as  the  hlue  colouration  will  not  he 
developed  if  water  he  in  excess  ;  and  even  after  it  has  heen  produced, 
the  addition  of  a  certain  proportion  of  that  suhstance  quickly  causca 
its  disappearance.  Such  heing  the  case,  the  hest  way  of  employing 
the  test,  according  to  my  experience,  is  to  place  three  or  four  drops 
of  the  molyhdic  solution  in  a  small  white  porcelain  capsule,  and  having 
heated  them  slightly,  allow  one  or  two  drops  of  the  liquid  to  he 
examined  to  glide  or  fall  gently  on  the  acid  solution,  when  there  will 
he  developed,  either  immediately  or  after  a  few  moments,  the  hlue 
colouration.  And  where  the  alcohol  is  very  largely  diluted  with 
water,  it  is  hotter  to  continue  the  gentle  heating  of  the  test  solution 
for  some  time,  to  concentrate  it  or  expel  as  much  water  from  it  as  pos- 
sible, before  adding  the  liquid  to  be  tested,  for  in  this  way  I  have 
succeeded  in  detecting  the  spirit  in  mixtures  so  dilute,  as  to  give  no 
hlue  reaction  when  added  immediately  to  the  test  solution  on  its  being 
simply  warmed.  As  regards  the  application  of  heat,  I  must  observe 
that  the  temperature  of  the  acid  solution  must  not  be  raised  too  high, 
for  if  it  be  heated  till  the  acid  evolves  its  dense  vapours,  or  begins  to 
boil,  the  solution  will  of  itself  alone,  from  its  partial  decomposition, 
develope  a  more  or  less  blue  colouration,  which  will  become  more  per- 
ceptible on  its  cooling.  But  such  an  occurrence  can  be  easily  avoided 
by  employing  a  water-bath  as  the  heating  >agent ;  for  I  have  found 
that  a  temperature  of  212°  F.  is  incapable  of  so  acting  on  the  test 
solution — at  least  an  exposure  of  several  hours'  duration  to  that  heat 
failed  to  produce  the  slightest  blue  colouration,  and  a  much  lower 
temperature  than  that  suffices  for  the  application  of  the  test. 

I  should  here  state  that  the  molyhdic  or  test  solution  which  I  have 
generally  employed  was  made  by  dissolving  at  a  gentle  heat  one  part 
by  weight  of  molyhdic  acid  in  ten  parts  of  strong  and  pure  sulphuric 
acid,  but  the  exact  strength  of  this  solution  as  regards  the  amount  of 
molyhdic  acid  it  contains  seems  to  be  immaterial. 

I  may  observe  that  the  colouration  produced  in  the  reaction 
stated  disappears  after  a  variable  interval  of  exposure  to  the  air— a 
circumstance  which  is  due,  as  I  have  ascertained,  to  the  absorption  of 
moisture  from  the  atmosphere,  and  not  to  the  reoxidation  of  the 
molybdenum  compound,  as  might  have  been  supposed;  for  amongst 
other  facts  in  proof  of  this,  I  may  state  that  after  it  has  thus  disap- 
peared, it  may  be  readily  restored  either  by  expelling  the  water  so 
absorbed  by  a  gentle  heat ;  or,  more  slowly,  by  placing  the  mixture 
under  a  desiccator,  and  thus  removing  it  by  spontaneous  evaporation 
at  the  ordinary  temperature.  Such  being  the  case,  it  is  evident  that, 
where  the  test  solution  has  been  too  much  diluted  for  the  immediatc^ 
development  of  the  colouration  described,  expelling  the  excess  of 
water  by  heating  the  mixture  on  a  water-bath,  it  may  be  made  to 
exhibit  itself. 

But  the  necessity  for  such  evaporation  should,  if  possible,  bo 
avoided,  which  in  most  cases  will  be  so,  by  using  only  a  drop  or  two 


Davy — On  a  New  Chemical  Test  for  Alcohol  681 

of  the  liquid  under  examination,  and  by  employing  the  strongest 
sulphuric  acid  in  making  the  test  solution ;  for  it  is  very  probable 
that  much  of  the  spirit  contained  in  the  liquid  would  be  lost  during 
its  evaporation  in  the  water-bath.  Besides  there  would  be  some  risk 
that  the  indications  of  the  test  might  be  more  or  less  interfered  with 
from  particles  of  dust  or  organic  matter  getting  into  the  mixture 
during  that  process. 

The  reaction  which  has  been  described,  I  should  state,  is  not  pecu- 
liar to  ordinary  or  ethylic  alcohol,  but  is,  more  or  less,  readily  de- 
veloped by  others — at  least  I  found  it  to  be  so  in  the  case  of  methylic, 
propylic,  butylic,  and  amylic  alcohols,  those  being  the  only  ones 
I  had  for  my  experiments.  But  it  is  more  than  probable  that  some 
at  least  of  the  other  alcohols  may  act  in  a  similar  manner ;  however, 
the  reaction  is  much  more  rapid  and  striking  in  the  case  of  ethylic 
than  in  that  of  any  of  the  other  alcohols  mentioned.  I  found  also 
that  certain  salts  of  the  radicles  of  those  alcohols  produced  a  some- 
what similar  reaction,  as  well  as  ethylic  ether  and  aldehyde,  and  also 
several  organic  matters  which  are  readily  susceptible  of  oxidation. 

The  circumstance  that  the  reaction  described  is  not  peculiar  to 
ethylic  alcohol  will,  no  doubt,  lessen  its  value  as  a  positive  test 
for  that  substance ;  but  a  similar  objection  appertains  to  all  tho 
other  known  tests  for  that  compound,  as  their  indications  are  not 
peculiar  to  that  alcohol  alone,  if  we  except,  perhaps,  Berthelot's  test, 
which  is  founded  on  the  development  of  benzoic  ether  by  the  action 
of  benzoic  chloride,  along  with  caustic  potash  on  ethylic  alcohol. 
But,  owing  to  the  trouble  attendant  on  the  preparation  of  benzoic 
chloride,  and  some  other  practical  inconveniences  connected  with  the 
application  of  that  test,  it  is  not  likely  that  it  will  ever  come  to 
be  one  of  very  general  employment. 

The  test,  however,  which  I  have  brought  before  the  Academy  has 
this  advantage  over  those  already  known,  that  it  far  exceeds  (accord- 
ing to  my  experiments)  any  one  of  them  in  point  of  delicacy.  And 
though  the  circumstance  that  the  blue  reaction  produced  in  the  case 
of  this  test  is  not  peculiar  to  ethylic  spirit  lessens,  as  before  observed, 
its  value  for  the  detection  of  that  substance,  this  is  just  what  ren- 
ders the  test  of  more  general  applicability;  for  by  its  aid  certain 
impurities  or  adulterations  may  be  at  once  detected  in  different  sub- 
stances or  compounds,  which  in  a  state  of  purity  should  not  contain 
any  matter  capable  of  acting  on  the  molybdic  solution  employed  in 
this  test.  I  may  refer  to  two  important  substances  as  examples,  viz., 
chloroform  and  chloral  hydrate,  which  are  now  so  extensively  em- 
ployed in  medicine  and  surgery  for  a  number  of  useful  purposes ;  and, 
being  agents  of  great  power,  it  is  of  much  importance  that  they 
should  be  free  from  the  accidental  impurities  of  imperfect  preparation, 
as  well  as  from  the  frauds  of  intentional  adulteration,  which  may 
cither  impair  their  therapeutic  value,  or  even  increase  the  danger 
of  their  administration.  For  there  can  be  but  little  doubt  that  in  some 
instances  the  serious  and  even  fatal  effects  resulting  from  their  uso 


582  Proceedings  of  the  Royal  Irish  Academy. 

may,  in  part  at  least,  have  been  attributable  to  the  impurities  or 
adulterations  of  the  chloroform,  or  of  the  chloral  hydrate  employed. 
Now,  as  I  find  that  neither  chloroform  nor  chloral  hydrate,  in  their 
pure  condition,  have  any  apparent  action  on  the  molybdic  test,  but 
that  many  of  their  usual  impurities  develope  the  blue  reaction,  it 
affords  us  a  ready  means  of  testing  their  purity.  Thus,  as  regards 
chlorofoi-m,  one  of  its  common  impurities  is  ethylic  alcohol,  which 
it  may  contain  either  from  imperfect  preparation,  or  from  fraudulent 
addition,  the  very  high  price  of  chloroform  offering  a  great  temptation 
to  the  unscrupulous  vendor  to  increase  its  bulk  or  weight  by  the  addi- 
tion of  alcohol,  which  so  readily  mixes  with  it.  I  have  found  that 
the  molybdic  test  at  once  enubles  us  to  detect  such  an  adulteration, 
even  where  it  occurs  in  very  small  proportions  in  chloroform.  Thus, 
in  one  experiment,  I  mixed  one  part  of  rectified  spirit  with  a  hundred 
parts  by  volume  of  pure  chloroform,  and  one  drop  of  this  mixture 
being  brought  in  contact  with  three  or  four  drops  of  the  molybdic 
solution,  previously  warmed  in  a  water-bath,  gave  an  immediate  deep 
blue  colouration  from  the  spirit  contained  in  it ;  and,  in  a  second  ex- 
periment, with  a  mixture  of  one  part  of  spirit  to  a  thousand  parts  of 
chloroform,  a  single  drop  of  the  mixture,  being  similarly  treated, 
developed  a  faint  blue  reaction.  Indeed,  so  searching  is  this  test 
as  regards  the  purity  of  chloroform,  that  I  was  unable  to  obtain  any 
sample  of  that  substance  in  commerce  sufficiently  pure  not  to  give 
a  blue  reaction  with  the  molybdic  test,  owing  to  the  minute  quanti- 
ties of  volatile  oils,  and  other  impurities,  they  contain ;  and  for  my 
experiments  I  was  obliged  to  repurify  the  commercially  pure  chlorofonn 
to  obtain  a  sample  which  would  give  no  coloured  reaction  with  my 
test. 

In  the  case  of  chloral  hydrate,  it  is  stated  that  one  of  its  usual 
impurities  is  the  chloral  alcoholate  (a  compound  in  which  alcohol, 
instead  of  water,  is  combined  with  anhydrous  chloral),  and  that 
this  substance  has  somewhat  different  effects  on  the  system  from 
those  produced  by  the  hydrate.  This  compound,  owing  to  the 
alcohol  it  contains,  gives  the  blue  reaction  with  the  molybdic  test,  and 
I  have  found  that  where  the  chloral  hydrate  contained  even  so  small 
a  proportion  of  the  alcoholate  as  one  part  in  a  thousand  parts,  a 
little  of  such  a  sample,  being  taken,  indicated  its  presence  when 
examined  by  the  molybdic  test ;  and  it  is  probable  that  some  of  the 
other  impurities  which  are  met  with  in  this  important  substance  may 
be  similarly  detected. 

Those  two  examples  are  sufficient  to  indicate  the  use  to  which  this 
test  may  be  applied  in  the  determination  of  the  purity  of  different 
substances  used  in  medicine,  as  well  as  in  scientific  research. 

Finally,  I  would  remark  that,  as  the  reaction  of  molybdic  acid 
on  ethylic  alcohol  is  so  sensitive  and  prompt  in  its  action,  I  entertain 
the  hope  that  there  may  yet  be  founded  on  it,  not  merely  this  qualita- 
tive test,  but  likewise  a  means  for  the  quantitative  determination  of 
that  important  alcohol. 


Wright — On  a  Neio  Genm  of  the  Family  Pandarina,     58S 


L. — Ojt  k  New  Gentjs  and  Species  belonging  to  the  Family 
Pandarina.  By  Edward  Pebceval  Weight,  M.D.,  F.L.S.,  Pro- 
fessor of  Botany,  Dublin  University.     (With  Plate  35.) 

[Read  May  11,  1874.] 

Rhinodon  ttpicus,  Smith,  is  one  of  the  largest  and  one  of  the  least 
known  of  the  sharks.  It  was  originally  described  by  the  late  Sir  A. 
Smith,  from  a  young  specimen  about  1 7  feet  long,  found  near  Cape- 
town. "  It  was  the  only  one  that  had  been  seen  at  the  Cape  within 
the  memory  of  any  of  the  fishermen.  At  the  time  it  was  discovered, 
it  was  swimming  leisurely  near  the  surface  of  the  water,  and  with  a 
certain  portion  of  the  back  above  it.  When  approached,  it  manifested 
no  great  degree  of  fear,  and  it  was  not  before  a  harpoon  was  lodged  in 
its  body  that  it  altered  its  course  and  quickened  its  pace.  The  pre- 
pared specimen  is  deposited  in  the  Museum  of  the  Jardin  des  Plantes 
of  Paris."* 

The  true  habitat  of  this  remarkable  species  appears  to  have  re- 
mained unknown  until  during  a  visit  paid  to  the  Seychelles  in  1 867. 
I  found  it  at  home  in  the  waters  surrounding  these  pleasant  islands. 
The  size  to  which  this  great  sluggish  fish  grows  presents  many 
obstacles  to  obtaining  specimens  of  it.  I  have  heard  of  some  indivi- 
duals being  seen  of  about  70  feet  in  length ;  I  have  seen  some  that  I 
believe  to  have  exceeded  50  feet ;  my  friend,  Mr.  Swinburne  Ward, 
the  then  Civil  Commissioner  of  these  islands,  measured  one  that 
a  little  exceeded  45  feet  in  length ;  and  I  have  had  the  opportunity 
of  dissecting  two  specimens,  one  of  which  was  1 8  feet  long  from  tho 
tip  of  the  nose  to  the  end  of  the  caudal  fin.  Rhinodon  typicus, 
though  a  large,  is  a  quiet,  harmless  fish,  with  a  mouth  of  immenso 
width,  and  jaws  furnished  with  very  small  teeth.  I  found  largo 
masses  of  algae  in  their  stomachs,  so  that  at  one  time  I  was  inclined  to 
think  it  was  an  herbivorous  shark.  Probably,  however,  it  derives  its 
nourishment,  in  part  at  least,  from  minute  crustaceans  and  other 
oceanic  animal  forms,  which,  it  may  take  in  along  with  masses  of  float- 
ing weed,  and  then  ejecting  the  water  through  the  strange  mesh-like 
structures  that  unite  the  edges  of  the  great  gill  openings,  obtain  by  so 
doing  enough  to  swallow.  Be  this  as  it  may,  I  found  on  the  surface 
of  these  meshes  the  little  parasitic  crustacean,  which  it  is  the  object 
of  this  paper  to  describe.  The  absence  of  parasites  was  remarkable. 
Some  forty  or  fifty  of  the  new  form  alone  rewarded  a  very  careful 
search.  The  sharks  hsui  been  harpooned  in  the  evening,  and  brought 
ashore  by  sunset  (about  6  o'clock).  Word  was  at  once  sent  to  me. 
I  was  at  the  time  stopping  exactly  at  the  opposite  side  of  the  island, 

^  Illustrations  of  the  Zoology  of  South  Afiica.  By  Andrew  Smith,  M.D. 
Pisces,  Plate  26. 


684  Proceedings  of  the  Royal  Irish  Academy. 

and  was  on  the  spot  the  next  morning  before  minrise,  so  that  I  was 
enabled  to  examine  the  specimen  while  it  was  still  quite  fresh.  The 
following  will  serve  as  a  diagnosis  of  the  new  form : — 

Family — PANDABiyi.. 

Bostrum  longum,  angustum.     Palpi  articnlati,  foliacei. 

Rtasiotes  rhinodontis,  gen.  et  spec.  nov.  (Plate  35,  figs.  1  to  14). 

The  cophalothorax  is  nearly  as  broad  as  long,  projected  somewhat 
in  front  where  the  frontal  lamina  becomes  conspicuous.  It  is  very 
transparent,  which  will  account  for  the  markings  to  be  seen  on  figure 
2,  where  there  is  an  appearance  as  if  the  cephalothorax  were  seg- 
mentiHl.  The  sides  project  backwards,  forming  lobes  so  as  to  cover 
the  free  edges  of  the  first  abdominal  ring.  The  first  abdominal  ring 
is  narrow,  not  extending  at  either  side  so  as  to  touch  the  prolonga- 
tioD  of  the  cophalothorax.  Tlie  second  abdominal  ring  is  somewhat 
broader  and  even  wider,  with  d(»licately  ciliated  appendages,  somewhat 
like  those  to  be  met  with  in  Demoleus  paradoxus.  Heller.  The  last 
ab<lonunal  ring  is  furnished  with  very'  feebly  developed  wing-like 
projections,  which  lie  slightly  over  the  largely  developed  genital 
ring ,  the  edges  of  these  rings  are  clothed  with  bristle-like  hairs. 

The  genital  ring  is  rounded  in  the  front  and  at  the  sides,  obtusely 
truncated,  and  somewhat  notched  behind,  a  little  less  than  one-half  in 
length  of  the  cephalothorax.  The  caudal  ring  is  narrow — quite hidunder 
the  genital  ring — but  the  caudal  appendages  (figure  14)  are  visible. 

The  anterior  antennae  (figure  5)  are  biarticulate,  and  spring  from 
the  under  surface  of  the  frontal  lamina ;  the  first  joint  is  twice  as 
broad  and  as  long  as  the  second,  and  just  behind  its  articulation  with 
the  second  it  is  set  over  with  a  few  minute  bristle-like  hairs;  the 
second  ends  abruptly  in  two  or  three  bristles.  The  posterior  antennie 
(figure  7)  are  stout  and  four-ijointcd ;  the  third  joint  is  twice  as  long 
as  broad,  and  is  barely  covered  by  the  front  portion  of  the  cephalo- 
thorax ;  the  fourth  joint  consists  of  a  long  incurved  claw.  The 
rostrum  (figure  6a)  is  long  and  narrow,  consisting  of  two  halves  in- 
closed in  a  sheath  each  of  which  (figure  6c)  is  terminated  by  a  series 
of  tooth-like  projections.  The  palpi  (figure  6a)  are  small,  feebly 
biarticulate,  and  very  slightly  foliaceous.  The  base  of  the  rostrum 
with  the  palpi  is  situated  between,  and  a  very  little  below,  the  origin 
of  the  posterior  antennae. 

The  first  pair  of  maxillary  feet  (figure  3)  arc  of  the  shape  and  form 
usually  met  with  in  this  group,  but  just  at  the  base  of  the  chelae,  and 
on  their  outer  surface,  there  is  a  scale-like  body  (figure  8a),  which  is 
thickly  set  with  short,  stiff  hairs  of  the  same  nature  as  those  which  are 
developed  along  the  margins  of  the  pincers.  The  second  pair  of 
maxillary  feet  (figure  9)  are  broad  and  large:  the  claw-like  terminal 
joint  can  project  beyond  the  edge  of  the  cephalothorax;  both  the  third 
and  fourth  claw -joint  carry  a  stiff  bristle. 


Wright — On  a  New  Genus  of  the  Family  Pandarina,      585 

The  four  pairs  of  abdominal  feet  are  two-brancbed,  and  in  the  first 
three  pairs  each  of  these  branches  (figures  10,  11,  and  12)  are  two- 
jointed,  each  of  the  joints  being  clothed  with  large  bristles  lined  with 
hairs.  The  first  pair  possesses  the  smaller  number  of  bristles,  and  there 
are  no  bristles  on  the  first  joints ;  the  second  and  third  pair  have,  on 
the  inner  edge  of  both  the  first  joints,  a  well  marked,  long,  ciliated 
bristle.  The  fourth  pair  (figure  13)  is  not  fully  furnished  with 
bristles,  and  these  are  not  clothed  with  cilisB ;  and  they  are  also  not 
two-jointed,  and  in  this,  as  in  the  number  of  bristles,  differ  very  mate- 
rially from  the  first  three  pairs. 

The  average  length  of  the  specimens  examined  is  six  millim.  All 
the  specimens  met  with  were  females. 

In  conformity  with  the  practice  of  HcUer,  Steenstrup,  Lutken, 
and  others,  I  describe  the  swimming  feet  as  abdominal — (abdominal 
f  usspaare :  bagkropsfoddeme) ;  but  it  would  have  seemed  to  me  more 
natural  to  have  described  them  and  the  somites  from  which  they 
spring  as  thoracic.  Heller  gives*  a  conspectus  of  the  Family  Pandarina, 
including  all  the  genera  known  to  him.  This  new  genus  it  appears  to 
me  might  come  in  after  Demoleus,  the  remi  of  the  third  pair  not  being 
^  biarticulati\  and  not  being  *  setis  plumosis  omati.' 

*  Noyara-Expeditiozu    Zoologischer  Theil :  Crustacea,  p.  160,  about  1866. 


586  Proceedings  of  the  Royal  Irish  Acadefny, 


LI. — XoTEfl     ox     A     SMALL     COLLECTION     OF    FoRAMIKIFERA    FROM    THl 

Betchklles.    By  E.  Percetal  Wright,  M.  D.,  Secretary  to  the 
Academy, 

[Read  January  24, 1876.] 

"While  at  the  Seychelles,  in  1 867,  I  made  several  collections  of  the 
Foraminifera  mot  with  while  dredfring.  These  were,  for  the  most  part, 
preserved  in  spirits  of  wine  ;  and,  unfortunately,  were  lost.  One 
dredpnp,  made  in  ahout  eijrht  fathoms  of  water,  ofF  the  entrance  of 
the  Harhour  of  Port  Victoria,  hetween  the  Island  of  St.  Anne  ami 
Lonp:  Island,  was,  however,  preserved  in  a  dry  state  ;  the  bottom  con- 
sisted for  the  most  part  of  a  coarse,  white  sand,  mixed  with  fracrments 
of  shells,  spicules  of  alcyonnrians,  and  frag:ment8  of  coral,  and  evi- 
dently contained  numbers  of  Foraminifera.  I  am  indebted  to  my  frien] 
Henry  Bowman  Brady,  F.  R.  S.,  for  the  names  on  the  following  list: 


FORAMHriFERA. 

1.  Cornuspira  foUaceOy  Philippi,  sp. 

(1844,    Orhis  foliaceus,  Enum.  Moll.  Sicil.,  vol.  ii,,    p.   147, 
pi.  24,  fijr.  26).     Medium-sized  specimens,  rare. 

2.  JBiloculina  elovgatOy  d'Oi  bigny. 

(1826,  Ann.  Sci.  Nat.,  vol.  vii.,  p.  298,  No.  1).     Rare. 

3.  Biloculina  contrariay  d'Orbig^iy. 

(1846,  For.  Foss.  Yienne,  p.  266,  pi.  16,  figs.  4-6).  Very  rare. 

4.  Triloculina  trigonula,  Lamarck,  sp. 

(1804,   Miliolites  triyanula,  Ann.  Mus.,  vol.  v.,  p.  351,  No.  3). 
Iliire. 

5.  Trilocidina  ohlongay  Montagu,  sp. 

(1803,  Vermiculum  oblongum,  Test.  Brit.,  p.  522,  pi.  14,  fig.  9). 
Rare. 

6.  Triloculina  Brongniartiana^  d'Orbigny. 

(1840,  Foram.  Cuba,  p.  156,  pi.  10,  figs.  6-8).   Somewhat  rare. 

7.  Quinqueloculina  seminulumy  Linne,  sp. 

(1767,  Serpula  seminuluniy  Syst.  Nat.,  12th  ed.,  p.  1264,  No. 
791).    Rather  common. 

8.  Quinqtteloculina  suhrotunda^  Montagu,  sp. 

(1803,  Vermiculum  suhrotundumy  Test.  Brit.,  p.  521).     Rare. 

9.  Quinqueloculina  Ferussaciiy  d*Orbigny. 

(1826,  Ann.  Sci.  Nat.,    vol.  vii.,  p.  301,  No.  18 — Modelc, 

No.  32). 
10.  Quinqueloculina  agglutinam^  d'Orbigny. 

(1840,   Foram.    Cuba,   p.   168,  pL    12,   figs.    11-13).     Very 

common. 


Wright — On  Foraminifera  from  the  Seychelles,        687 

11.  Spiroloeulina  eanalieulatay  d'Orbigny. 

(1846,  For.  Fobs.  Vienne,  p.  269,  pi.  16,  figs.  10-12).  Small, 
very  rare. 

12.  Hauerina  eompreisa,  d'Orbigny. 

(1846,  For.  Fobs.  Vienna,  p.  119,  pi.  5,  figs.  25-27).    Small, 
very  rare. 

13.  AheoUna  sabtdoMf  Montfort,  sp.  > 

(1808,  MxUoUUb  sabtUosus,  Conch.  Syst.,  vol.  i.,  p.  174).     Me- 
dium, rather  rare. 

14.  OrhitoUtes  eamplatiataf  Lamarck. 

(1801,  Anim.  sans  Vert.,  p.  876).     Very  common. 

15.  Lagena  squamosay  Montagu,  sp. 

(1803,    Vertniculum  squamosum^   Test.   Brit.,   p.   526,  pi.  14, 
fig.  2).     Small,  very  rare. 

16.  Lagena  marginata^  Walker  and  Jacob,  sp. 

(1784,   Serpula  [Lagena']  marginata^  Test.  Min.,  p.  3,  pi.  1, 
fig.  7).     Small,  very  rare. 

17.  Olohigerina  bulloides,  d'Orbigny. 

(1826,  Ann.  Sci.  Nat.,  vol.  vii.,  p.  277,  No.   1 — Modules, 
Nos.  17  and  76).    Medium,  rather  rare. 

18.  Textularia  agglutinane,  d'Orbigny. 

(1840,Foram.  Cuba,  p.  136,  pi.  1,  figs.  17, 18, 32-34).  Medium- 
sized  specimens,  common. 

19.  Bolivina  punctata,  d'Orhi^j, 

(1839,  Voyage  TAmer.  M6rid.,  p.  63,   pi.   8,   figs.    10-12). 
Small,  rare. 

20.  Vemeuilina  epinuloea,  Reuss. 

(1849,  Denkschr.  Akad.  Wissensch.  Wien.,   vol.  i.,  p.  374, 
pi.  47,  fig.  12).     Mediu!m,  rare. 

21.  Flanorhulinafarctay  Fichtel  and  Moll,  sp. 

(1803,  Nautilus  farctus,  Test.  Micr.,  p.  64,  pi.  9,  figs.  y-t). 
Medium,  rare. 

22.  Dieeorhtna  glohularte,  d'Orbigny,  sp. 

(1826,  Roedlina  globulariSf  Aim.  Sci.  Nat.,  vol.  vii.,  p.  271, 
No.  1,  pi.  13,  figs.  1-4).     Medium,  rare. 

23.  Fulvtnulina  repanda,  Fichtel  and  Moll,  sp. 

(1803,  Nautilus  repandus,  Test.  Micr.,  p.  35,  pi.  3,  figs,  a^) 
Rare. 

24.  Ptdvinulina  Canariensts,  d'Orbigny,  sp. 

{Rotalina  Canariensts,  d'Orb.,   1839,  Foram.  Canaries,  p.  130, 
pi.  1,  figs.  34-36).    Very  rare. 

25.  Italia  Beccarii,  Linne,  sp. 

(1767,  Nautilus  Beeearii,  Syst.  Nat.,  12th  ed.,  p.  1162,  No. 
276).     Small,  rare. 

26.  Rotalia  orbicularis,  d'Orbigny,  sp. 

(1826,   Oyroidina  orbicularis,  Ann.  Sci.  Nat.,  vol.  vii.,  p.  278, 
No.  1 — Modele,  No.  13).    Small,  very  rare. 

R.  I.  A.  PROC,  >BK.  n»  ^OL.  11.,  BCIBNCB.  3   L 


588  Proceedings  of  the  Eoyal  IrUh  Academy, 

27.  Cymhalopora  Poeyi,  d*Orbigny,  sp. 

{RoHdina  Poeyi,  d'Orb.,  1840,  Foram.  Cuba,  p.  100,  pi.  3,  figs. 
18-20).     Large,  very  common. 

28.  Tinoporu9  lavis,  Parker  and  Jones,  sp. 

(1860,  OrhiUlina  Imie,  Ann.  and  Kag.  Nat.  Hiat.,  drdser., 
vol.  vi.,  p.  33,  No.  7).    Large,  rare. 

29.  TincporuB  vmeularitf  Parker  and  Jones. 

(1860,  OrhiMina  resictdaris,  Ann.  and  Mag.  Nat.  Hist.,  Srd 
ser.,  vol.  vi.,  p.  33,  No.  6).    Very  rare. 

80.  PaUUiMy  sp. 

(A  minute  discoidal  form,  resembling  a  septate  SpirtUina:  not 
corresponding  with  any  figured  species  I  can  refer  to. 
H.B.B.)    Very  rare. 

81.  AmphtBtegina  vulgaris,  d*Orbigny. 

(1826,  Ann.  Sci.  Nat.,  vol.  vii.,  p.  305,  No.  8— Module, 
No.  40).     Small,  common. 

82.  Cperetdina  eomplanaiay  Defrance,  sp. 

(1822,  Lentieulites  ecmplanata,  Diet.  Sci.  Nat.,  voL  zzv., 
p.  453).  (This  thick  OpereuHnSy  common  in  the  Red  Sea, 
Indian  Ocean,  and  Australia,  is  not  the  typical  0.  eompUmatay 
but  rather  an  intermediate  form,  showing  the  dose  relation- 
ship to  Nummulinm  plantdata).    Kedium  size,  rare. 

83.  Kummutina  planulata,  Lamarck,  sp. 

{Zentictditei  plantdataf  Lamarck,  1804 ;  Ann.  Mua.,  p.  187, 
No.  1).    Kedium,  rare. 

84.  PolysUmeUa  eritpa,  Linn6,  sp. 

(1767,  Nautilui  eriipui,  Syst.  Nat.,  12th  ed.,  p.  1162). 
Small,  rare. 

85.  PolfsUmeUa  siriatopunctata,  Fichtel  and  Moll,  sp. 

(1803,  Nautilus  striaUpuneiatus,  Test.  Micr.,  p.  61,  pi.  9, 
figs.  «-«).     Small,  very  rare. 

36.  Nmionina  asteritans,  Fichtel  and  Moll,  sp. 

(1803,  Nautilus  asterizans,  Test.  Micr.,  p.  37,  pi.  3,  figs.  e-h). 
Small,  very  rare. 

37.  Nimionina  scapha,  Fichtel  and  Moll,  sp. 

(1803.  Nautilus  seapha.  Test.  Micr.,  p.  105,  pi.  19,  figs.  i^/). 
Medium,  very  rare. 

38.  JETeterostegina  depressa,  d'Orbigny. 

•    (1826,  Ann.  Sci.  Nat.,  vol.  vii.,   p.  303,  pi.   17,  figs.  5-7). 
Large,  very  common. 


Brady — On  Foraminif era  from  the  Loo  Choo  Islands.    589 


LII. — On  80XE  FoBAMDriFXRA  FBOM  THE  LoO  ChOO  IsLAlTDS.      Bj 

HBirBT  B.  Beady,  F.  K.  S. 
[Bead  May  8, 1876.] 

A  PBESSXD  and  mounted  specimen  of  a  small  alga,  labeled  "Zaureneia 
panieulata.  Loo  Choo  Islaads,"  was  recently  sent  to  me  by  Dr.  £. 
Perceval  Wright,  with  the  suggestion  that  some  Foraminifera  which 
had  been  entangled  in  its  meshes  might  be  worth  examination,  and 
that  at. any  rate  it  would  be  interesting  to  know  what  particular 
species  had  lived  amongst  its  miniature  branches.  As  the  seaweed 
itself  was  of  some  value,  two  or  three  square  inches  were  taken,  and 
the  portion  as  separated  yielded  examples  of  the  following  species  of 
Foraminifera,  some  of  them  in  sufficient  number  to  supply  two  or 
three  good  mountings. 

Hatterina  etmifreaaa,  d'Orbigny. 
Quinquelocuhna  svh-otunda,  Montagu. 

„  hicomUy  Walker  and  Jacob. 

„  omatmima,  Eauer. 

Peneroplts  pertusuSf  Batsch. 
Vertebralina  itrietay  d'Orbigny. 
Orlitolites  eomplanatuSj  Lamarck. 
Diseorhina  rosacea,  d'Orbigny. 

,,        ghbularisj  d'Orbigny. 
Planorhdina  Mediterranensis,  d'Orbigny. 
Calearina  Spengleriy  Omelin. 

„        ealeary  d'Orbigny. 

,,        hispidaf  spec.  nov. 
Tinoporus  haeulatus,  Montfort. 
Cymbalopora  Poeyi,  d'Orbigny. 
HeterosUgina  depressa,  d'Orbigny. 

Although  a  considerable  list,  considering  that  the  entire  weight 
of  seaweed,  shells,  and  all  could  not  be  more  than  fifteen  or 
twenty  grains,  one  or  two  forms  were  represented  by  a  single  speci- 
men only,  but  no  species  has  been  retained  of  which  a  good  charac- 
teristic example,  large  or  small,  was  not  present ;  doubtful  forms  were 
rejected,  else  the  list  might  have  been  considerably  extended.  Tlie 
most  abundant  species  of  Calearina  was  the  pretty  hispid  modification 
figured  by  Dr.  Carpenter  (Introd.  Foram.  PI.  xiv.,  fig.  6),  but  not 
hitherto  described  or  named  as  far  as  I  know.  I  propose  to  call  this 
C.  hispida,  and  its  characters  will  stand  as  f oUow.  I  have  met  with 
larger  specimens  in  Australasian  sands,  but  have  never  seen  any  so 
beautifully  perfect. 

Calcabina  Hispida,  spec,  nov. — Test  free,  unequally  biconvex,  ro- 
talian  :  margin,  thin  lobulate  or  rowelled ;  segments  numerous,  slightly 


590  Proceedings  of  the  Royal  IrUh  Academy. 

inflated ;  peripheral  borders  thin,  rounded,  angular,  or  produced  Bai&- 
ciently  to  form  radiating  spurs.  Surface  covered  with  adpressed  spiny 
processes,  obscuring  the  sutures,  except  those  of  the  later  chambers. 
Diameter  V^  inch  (1*3  mm.)  or  more.  The  characters  are,  indeed,  yery 
much  those  of  Cakarina  ealear,  excepting  for  the  superficial  spiny 
armature. 

QuinfueloeuUna  cmatimma  (Kauer,  Sitzungsb.  K,  Akad.  Wiss. 
Wien.,  1868,  vol.  Iviii.,  p.  151,  pi.  3,  fig.  2)  deserves  a  passing  notice. 
It  is  an  interesting,  highly  ornate  form  with  transverse  cr^iulations, 
crossed  by  longitudinal  strisa,  and  though  I  had  previously  found  it  in 
some  Polynesian  sands,  it  has  not  hitherto  been  recorded  as  a  recent 
species.  Dr.  Kauer's  specimens  were  from  the  Miocene  of  the  Banat, 
in  Austria.  Only  a  single  example  was  found  in  this  Loo  Choo 
gathering,  and  that  is  slightly  broken. 

At  the  time  I  received  the  seaweed  from  Dr.  "Wright,  I  was  en- 
deavouring to  summarize  what  was  known  of  the  parasitic  types  of 
Foraminif era  in  connection  with  my  work  upon  the  Ehizopod-fauna 
of  the  carboniferous  rocks,  and  I  had  arrived  at  the  conclusion  that 
adherent  growth,  at  one  period  of  life  or  another,  was  a  much  more 
common  and  more  significant  character  in  this  group  of  organisms 
than  has  hitherto  been  supposed.  It  was,  therd^ore,  of  interest  to 
ascertain  not  only  what  species  of  Foraminif  era  were  present,  but  how 
many  of  them,  if  any,  were  really  parasitic,  and  not  simply  entangled 
in  the  meshes  of  the  weed  amongst  which  they  had  lived,  or  adherent 
by  the  mucilaginous  matter  coating  the  surface.  The  piece  of  the 
alga  which  had  been  separated,  consisting  chiefly  of  the  root  and  the 
commencement  of  the  larger  branches,  was  therefore  put  into  warm 
water  and  allowed  to  macerate  for  twenty-four  hours,  by  which  time 
it  had  swollen  to  its  original  size.  Eepeated  sharp  agitation  during 
the  maceration  served  to  liberate  most  of  the  Foraminifera.  It  was 
then  cut  into  little  pieces,  and  the  filaments  of  a  conferva  with  which 
it  had  been  associated  in  growth  were  carefully  removed.  The  pieces 
were  put  into  a  sieve  and  washed  under  a  strong  stream  of  warm 
water  from  a  tap,  using  every  means  even  to  the  extant  of  some  vio- 
lence to  dislodge  anything  that  had  not  some  connexion  with  the 
surface  of  the  plant  beyond  mere  chance  adhesion.  The  specimens 
that  remained  were  comparatively  few  in  number,  arid  pertained  to  a 
limited  range  of  species,  but  for  the  most  part  they  had  evidently  lived 
in  the  parasitic  condition  in  which  they  were  foimd.  They  were 
chiefly  the  young  of  OrhitoliUs  eomplanatus  and  Cymhalopora  Poeyi  with 
small  examples  of  Pktnorhdina  MediterranenHs,  The  last-named  needs 
no  comment,  as  it  is  an  essentially  parasitic  species,  but  I  am  not 
aware  that  either  OrhitoliU$  or  Cymbalopora  has  ever  before  been  noticed 
in  this  condition.  The  little  specimens  of  Cymbalcpora  might  have 
passed  for  the  fry  of  one  of  the  other  rotalian  genera  but  for  the  pre- 
sence of  larger  specimens  of  the  same  species. 


Moore — On  Irish  Hepaticce.  591 


LIU. — ^BspOBT  ow  IsiSH  HsPATiCiB.    By  David  Moobe,  Ph.D.,  F.L.S. 
(With  Plates  43,  44,  and  45). 

[Bead  April  24, 1876]. 

Hesewith  I  lay  before  the  Academy  the  results  of  many  years'  re- 
searches among  the  Irish  Hepaticae. 

Since  I  received  the  grant  from  the  Academy,  I  visited  in  the  early 
period  of  1874  several  parts  of  the  County  of  Wicklow,  which  I  sup- 
posed to  be  likely  habitats  of  these  minute  plants,  and  among  other 
places  the  glen  of  Altadore,  or  Hermitage  Glen,  near  Delgany,  where 
the  rare  Irish  fern,  Trichomanes  radicans,  once  grew  very  sparingly, 
but  has  long  since  been  eradicated.  In  the  autumn  of  the  same  year, 
I  went  to  Connemara,  where  I  made  a  rather  extended  search  among 
the  mountains  of  that  country,  ascending  to  the  top  of  Mweelrea,  the 
highest  in  that  district. 

In  May,  1875,  I  visited  portions  of  the  Counties  of  Fennanagh 
and  Leitrim,  where  they  join  near  Manorhamilton,  and  where  I  found 
the  sides  of  the  lakes  and  glens  rather  favourable  for  the  growth  of 
cryptogams,  especially  Hepaticse.  This  district  is  in  close  proximity 
to  the  Ben  Bulben  range  of  mountains,  upon  which  in  Ireland  is 
found  the  most  distinct  trace  of  a  truly  Alpine  phanerogamic  flora. 
On  the  high  rocks  between  the  heads  of  Glenad  and  Gleniff,  Draba 
rupestris,  Saxifraga  nivalis,  and  Arabis  petraea,  all  three  truly 
Alpine  plants,  occur,  not  occurring  elsewhere  in  Ireland.  The  faces  of 
the  cliffs  are  clothed,  in  many  places,  with  two  of  the  most  lovely  of 
our  sub- Alpine  species,  namely — Saxifraga  oppositifolia,  and  Silene 
acaulis;  their  rosy  purple  flowers  can  be  seen  at  some  considerable 
distance,  and,  on  a  nearer  approach,  appear  patches  of  the  rare  Arenaria 
ciliata ;  this  district  being  its  only  British  locality.  Here  I  gathered 
several  rather  rare  HepaticsB  and  mosses.  In  October  I  made  another 
jjoumey  to  the  County  of  Kerry,  where  some  great  rarities  among  the 
Hepaticse  were  collected,  but  very  few  not  previously  known  to  grow 
there. 

This  family  of  plants,  like  the  Irish  mosses,  has  been  well 
studied  and  searched  for  by  former  botanists,  both  Irish  and  foreign. 
When  it  is  remembered  that  the  Counties  of  Kerry  and  of  Cork  are 
those  in  which  dwelt  two  of  the  most  gifted  cryptogamic  botanists 
that  Ireland  has  produced,  namely,  the  late  Dr.  Thomas  Taylor,  and 
Miss  Hutchins  of  Bantry,  it  is  not  much  to  be  wondered  at  that  few 
discoveries  remained  for  their  successors.  Of  Miss  Hutchins,  Sir  Jamcs^ 
Smith,  when  writing  his  English  Flora,  is  reported  to  have  said,  "  he 
believed  she  could  find  anytfong."  To  form  some  idea  of  her  great 
success  among  the  HepaticsB,  we  have  only  to  consult  the  pages  of 
Hooker's  ''British  Jungermanniae,"  where  her  name  is  more  or  less 
connected  with  nearly  every  rare  species  contained  in  that  grand  work. 

B.  I.  A.  FaO0.|  BXB.  II.,  VOL.  H.,  8CIXNCB.  8  M 


592  Proceedings  of  the  Royal  Irish  Academy. 

Dr.  Taylor  has  given  to  the  world  the  results  of  his  researches 
among  this  interesting  family   of   plants,   in  the    second   part  of 
Mackay's  **  Flora  Hihemica,"  where  he  descrihes,  under  the  genus 
Jungermannia,  all  the  species  which  were  known  to  him  up  to  1836. 
Of  the  foliaceous  kinds  seventy-five  species  are  enumerate,  besides 
the  Marchantiace©    and  Anthocerotace©,   comprising  eight  species, 
eighty-three  in  all.     Among  them  are  several  contributions  of  rare 
species  by  the  late  W.  Wilson  of  Warrington,  of  bryological  fame, 
who  collected  them  in  1829,  when  he  paid  a  long  visit  to  this  country, 
and  who  was  the  first  to  publish  and  describe  in  the  English  Flora  the 
rare  Dumortiera  irrigua,  under  the  name  of  Marchantia  irrigua.  After 
the  publication  of  the  **  Flora  Hibemica,"  Dr.  Taylor  discovered  several 
new  species,  descriptions  of  which  he  published  in  the  Transactions  of 
the  Botanical  Society  of  Edinburgh,  vols.  1-3.      In  1843  a  list  of  the 
Hepatic©  of  the  County  of  Cork  was  included  in  the  Flora  and  Fauna  of 
that  county,  which  was  published  by  the  Cuvierian  Society  of  Cork. 
About  fifty  species  are  therein  enumerated.     From  that  period  up  to 
1862  little  has  been  published  on  Irish  Hepatic©,  except  some  brief 
notes  of  additional  species  and  new  localities  by  myself  in  the  Pro- 
ceedings of  the  Dublin  University  Botanical  and  Zoological  Association, 
and  of  the  Dublin  Natural  History  Society.     Isaac  Carroll  of  Cork 
made  also  a  few  additions  about  this  time. 

In  1861  Dr.  Carrington  of  Eccles,  Lancashire,  spent  eleven  weeks 
in  Ireland,  chiefly  in  the  County  of  Kerry,  studying  and  collecting 
Hepatic©.     In  1863  he  published  the  result  of  his  labours  in  the 
Transactions  of  the  Botanical  Society  of  Edinburgh,  vol.  7,  part  ra., 
under  the  heading,  *'  Gleanings  among  the  Irish  Cryptogams."     In 
this  important  contribution  the  names  of  the  genera,  and  sections  into 
which  the  large  genus  Jungermannia  had  been  about  that  time  sub- 
divided, are  adopted.    He  does  not  describe  any  new  species,  but  he 
added  to  our  flora  one  species,  which  had  not  previously  been  noticed 
in  Ireland,  namely,  Jungermannia  obovata,  Nees.     Including  those 
which  he  found  himself,  and  those  which  he  gleaned  from  other  sources, 
Dr.  Carrington  raised  the  list  of  Irish  Hepatic©  to  about  100  species, 
with  numerous  varieties.   Another  very  important  contribution  has  re- 
cently been  published  by  Dr.  Lindberg,  Professor  of  Botany  in  the 
University  of  Helsingfors.  At  my  invitation  he  paid  a  visit  to  Ireland 
in  June  and  July,  1873,  and  was  my  guest  while  he  remained  in  this 
country.      I  accompanied  him  to  those  parts  of  Ireland  which  I  knew 
to  be  the  richest  in  this  particular  family  of  plants,  of  which  we  made 
large  collections.  During  the  month  of  July  1 873,  no  fewer  than  eighty- 
seven  species  of  Hepatic©  were  collected,  an  account  of  which  Dr.  Lind- 
bergpublished  in  the  Acta  Societatis  Scientiarum  Fennic©,  vol.  x.,"  under 
the  heading,  "  Hepatic©  in  Hibemia  mense  Julii  1873  lect©.*'  Among 
them  he  describes  several  species  new  to  science,  viz.,  Lejeunia  patens, 
L.  Moorei  and  Metzgeria  conjugata.     He  also  adds  to  the  list  Biccia 
sorocarpa,  Bisch.,  and  Scalia  Hookeri  (Lyell),  Gray,  besides  raising  to 
the  rank  of  species  a  few  which  had  previously  been  held  as  varieties. 


Moore — On  Irish  Hepaticce.  693 

Altogether,  the  subject  is  handled  by  him  in  a  masterly  way,  and 
whether  his  new  divisions  and  nomenclature  be  adopted  or  not  by 
future  botanists,  his  paper  is  a  very  important  contribution  to  science* 
He  divides  the  Hepaticss  into  three  sections.  1.  MarchantiacesB. 
2.  Jungermanniacese.  3.  AnthocerotacesB.  This  is  no  great  departure 
from  tiie  arrangement  of  previous  authors.  These  are  again  grouped 
under  sub-sections,  according  to  the  nature  of  the  valves  of  the  capsule, 
whether  splitting  into  pieces  when  ripe  or  remaining  whole,  viz.,  Schi- 
zocarpsB  and  Cleistocarpse. 

The  JungermannisB  Schizocarpse  are  divided  into  two  principal 
divisions  differing  from  each  other  in  several  important  characters,  which 
are  fully  described,  but  chiefly  depend  on  the  position  which  the  Gamoe- 
cium  and  Andrcecium  occupy  on  the  plants.  These  he  calls  (a)  Anomo- 
gamo) ;  (Jbi)  Homogamee,  and  the  latter  he  still  further  divides  into 
"*  OpisthogamsB ;  and  *♦  Acrogamaa.  By  these  divisions  he  has 
been  enabled,  in  my  opinion,  to  group  the  species  together  more 
naturally  (with  a  few  exceptions)  than  has  been  done  by  any  pre- 
vious author.  What  may,  however,  be  found  fault  vrith  is  Dr. 
Lindberg's  endeavour  to  restore  the  names  of  genera  in  exact  con- 
formity with  the  law  of  priority.  The  dates  are  so  carefully  and 
clearly  set  forth  along  with  the  name  of  each  genus,  that  there  can  be 
no  disputing  the  matter.  It  is  well  known  that  Mr.  S.  P.  Gray,  father 
of  the  late  Dr.  J.  E.  Gray,  of  the  British  Museum,  was  the  first  to 
subdivide  the  comprehensive  genus  Jungermannia  into  smaller  genera, 
to  which  he  gave  names  in  his  **  Arrangement  of  British  Plants," 
published  in  1821,  a  fact  which  had  already  been  established  by  Mj. 
Oarruthers,  Director  of  the  Botanical  Department,  British  Museum,  in 
Seemann's  Journal  of  Botany,  vol.  iii.,  p.  297.  These  names  of 
Gray's  Dr.  Lindberg  has  in  many  instances  adopted,  though  some  of 
them  sound  very  oddly,  after  we  have  been  so  long  accustomed  to  the 
established  nomenclature  of  such  a  standard  work  on  Hepaticse  as  the 
**  Synopsis  Hepaticarum,"  by  Drs.  Gottsche,  Lindenberg  and  Nees, 
published  between  1844  to  1847.  That  there  is  a  farther  want  of  some 
recognised  standard  in  the  nomenclature  of  this  family  of  plants  is 
obvious,  and  may  be  seen  from  the  numerous  synonyms  of  various 
authors  which  Lindberg  and  Du  Mortier  have  brought  together. 

The  veteran  Belgian  Botanist,  M.  Du  Mortier,  having  published 
his  first  work  on  HepaticsB,  ''  Commentationes  Botanica),"  so  long  back 
as  1822,  and  others  of  importance  on  the  same  subject,  at  intervals 
from  that  period  till  1874,  when  his  large  work  "  Hepaticse  Europae" 
was  published,  has  all  that  time  been  altering  and  improving  the  dis- 
tinguishing characters  of  the  sub-orders  and  so-called  genera  of 
this  family  of  plants,  yet  in  the  last  work  new  divisions  and  new 
names  of  genera  are  to  be  found. 

The  characters  of  Hepaticse,  though  pretty  constant,  and  sufficient 
to  distinguish  the  genera,  are  .by  no  means  so  satisf  aotory  as  those  of 
the  Mosses.  Dr.  Taylor,  all  his  life,  held  the  opinion  that  it  was 
impossible  to  distinguish  satisfactorily  the  genera  of  Jungermannia 

dM2 


594  Proceedings  of  the  Royal  Irish  Academy. 

from  tlie  descriptions  given  of  them,  and  he  never  adopted  them,  but 
continued  to  name  his  new  species  as  they  occurred  to  him  by  the 
old  established  generic  name  Jungermannia  up  to  the  last,  though 
he  knew  they  belonged  to  genera  established  by  modem  authors. 
Even  the  late  Sir  William  Hooker,  who  studied  the  British  Junger- 
mannia with  a  rare  discriminating  power,  did  not  attempt  to  divide 
the  old  genus  Jungermannia,  but  was  content  to  place  the  species  in 
natural  groups,  which  are  pretty  much  the  same  as  those  now  adopted, 
several  of  them  being  represented  by  modem  genera.  His  great  work 
on  the  British  Jungermannia  is,  indeed,  one  of  the  most  beautiful  and 
most  exhaustive  ever  written  on  any  subject  of  natural  history.  In 
the  present  Eeport,  I  have  adopted  Dr.  Lindberghs  arrangement,  both 
for  the  sake  of  uniformity,  and  because  I  consider  it  the  most 
natural  yet  published. 

Ireland  is  extremely  rich  in  this  family  of  plants,  and  produces  a 
number  of  remarkable  species,  which  are  true  indicators  of  the 
climate  of  the  country.  Iliese  minute  vegetables,  some  of  which  are 
scarcely  visible  to  the  unaided  eye,  tell  of  heat,  moisture,  and  other 
climatal  circumstances,  much  more  accurately  than  the  flowering  plants 
of  the  country  do,  and  show  that  the  south-west  of  Ireland  approaches 
in  climatal  conditions  some  sub-tropical  parts  of  the  world. 

In  a  letter  from  the  well-known  traveller.  Dr.  Sprace  of  Wei- 
bum,  Yorkshire,  who  has  explored  a  very  large  portion  of  South 
America,  collecting  both  the  flowering  and  cryptogamic  plants  of  that 
country,  he  states  that ''  when  gathering  mosses  and  Hepaticee  on  the 
slopes  of  the  Andes,  he  was  reminded  of  the  Kerry  Mountains,  whose 
cryptogamic  vegetation  is  the  nearest  approach  in  Europe  to  that  of 
tropical  mountains."  Among  the  species  most  characteristic  of  a 
warm  and  moist  climate,  I  may  mention  particularly  Dumortiera 
irrigua,  Badula  xalapensis  (Radula  voluta,  Taylor),  found  also  in  New 
Granada,  Metzgeria  linearis,  which  grows  also  in  Jamaica,  and  Guada* 
loupe,  Frullania  HutchinsiaB,  variety  ^.,  in  the  Island  of  Java,  and 
the  minute  Lejeuniae.  Among  the  mosses  we  have  the  beautiful 
Hookeria  Iffitcvirens,  which  occurs  in  the  West  Indies,  besides  the 
Slillamey  Eem  (Trichomanes  radicans),  another  plant  which  extends 
to  the  West  Indies. 

I  have  spared  no  trouble  to  ensure  correctness  in  the  names  of  the 
plants,  for  which  purpose  I  have  frequently  consulted  both  Dr.  Car- 
rington  and  Professor  Lindberg,  who  have  always  very  kindly  assisted 
me  with  their  opinion. 

The  Irish  liabitats  may  be  relied  upon,  as  I  have  collected  nearly 
every  one  of  the  plants  with  my  own  hands,  at  some  time  or  other 
during  the  last  forty  years ;  having  for  this  purpose  travelled  over  a 
very  large  portion  of  Ireland,  from  east  to  west,  and  from  north  to 
south,  and  from  the  sea-level  to  the  tops  of  the  highest  mountains. 
The  chief  merits  of  this  Report  may  indeed  be  considered  to  consist  in 
its  giving  as  full  an  account  as  I  am  able  to  render  of  the  Irish  Hepa- 
ticse,  and  of  their  geographical  distribution  in  Ireland.  137  species 
of  them  are  enumerated. 


Moore — On  Irish  Hepaticce  595 

IRISH  HEPATIC^. 


SECnON  I.     FliOXDOS^.     MABCHAin:UCR£. 

Plants  with  stems  and  leaves  confluent  in  a  frond. 

A.      SCHIZOCABFJE. 

Family  1.  Maschajttibje. 
<lapsules  in  aggregate  capitula,  pendent  from  a  peltate  receptacle. 

Dioecious. —  Male  receptacle  pedunculated. 
Loculi  of  the  female  receptacle  2-Talyed. 
Colesule  4-5  cleft, MABCHAmnA. 

Dioecious. — Fertile  receptacle  hemispherical, 
rihbed  in  a  ray-like  manner,  and  lobed, 
involucres  attached  to  the  under  side  of 
the  lobes,  1-3  fruited.  Male  receptacles 
peltate,  peduncled,  with  the  antheridia 
immersed, Pseissia. 

Dioecious. — ^Male  receptacle  sessile,  disciform. 
Loculi  of  the  female  receptacle  tubulose, 
1-fruited.     Colesule  wanting,         .        .     Conogefhalus. 

Monoecious. — ^Antheridia  immersed  in  sessile 
crescent-shaped  disks  on  the  frond.  Fer- 
tile receptacle,  4-5  lobed.  Loculi  4-5, 
single-fniited.     Colesule  wanting,  .     Astebella. 

Dioecious. — ^Male  receptacle  almost  sessile,  pel- 
tate, hairy.  Female  receptacle  hairy, 
elevated  on  a  peduncle,  2-  to  6-  cleft. 
Loculi  1-valved.    Colesule  wanting,         .    Dxtxoetieea. 

Dioecious. — ^Male  receptacle  sessile.  Female 
receptacle  deeply  cleft.  Loculi  tubulose, 
1-valved,  fleshy.     Colesule  wanting,        .    Lunttlaeia. 

Family  2.     Taegioxie^. 

<]!ap8ules  solitary,  situated  near  the  apex  of  the  frond,  subsessile,  bi- 
valved,  witiiout  a  central  columella. 

Dioecious. — Male  receptacle  sessile,  in  abivalved 
loculus.  Capsule  shortly  pedicellated, 
situated  near  apex  of  frond,  opening 
irregularly, Tabgiona. 


•  696  Proceedings  of  the  Royal  Irish  Acadetny, 

B.    Cleistocarpjb. 

Capsules  ralyeless,  imbedded  in  the  substance  of  tbe  frond.  No  Elaters. 

Family  3.    RicciKiE. 

Fruit  immersed  in  upper  surface  of  frond, 

bearing  a  style,  inrhieh  is  protruded  above 

the  surface  of  the  frond,         .        .        .     Riccia. 
Fruit  globose,  adnate  to  under  surface  of  frond. 

Style  exserted, Eicciella, 

Fruit  immersed  in  frond,  and  not  protruded  on 

either  surface,        .....     Hicciocabpus. 

Sectiqk  II.    Fouo&£.    JuiroEBXAinaicE^. 
Plants  with  stems  and  leaves  distinct. 

A.       SCHIZOCARPJE. 

Capsules    solitary,   elevated    on  an  erect  foot-stalk,   or    subsessile. 
Elaters  with  spiral  fibres. 

Sub-tribe  1.     'Frvllajxieje, 

Involucral  bracts  wanting  or  indistinct. 

Colesule  trigonal,  rarely  round,  constricted  at 
the  mouth,  slightly  keeled  beneath.  In- 
volucral bracts  wanting  or  imperfect. 
Elaters  single-spired,      ....     Fbxtllakia. 

Colesule  contracted  at  the  mouth,  angular  or 
toothed.  Peduncle  articulated.  Capsule 
univalved.    Elaters  double-spired,  .        .     Lejxttkia. 

Colesule  compressed,  truncate.  Involucral 
bracts  wanting  or  indistinct.  Peduncle  not 
jointed.     Elaters  with  double  spires,       .     Radula. 

Colesule  compressed,  slightly  bilabiate.  Cap- 
sule univalved,  globular  or  cleft.  Elaters 
double-spired, Pobella. 

Sub-tribe  2.     Plevsozols. 

Involucral  bracts  present  and  distinct. 

Involucral  bracts  two,  deeply  bilobed.  Colesule 
long,  cylindrical,  mouth  denticulate,  de- 
curved  at  apex.  Capsule  quadrivalved,  of 
thick  texture.     Elaters  double-spired,      .    Piettrozu. 


Moore — Qn  Irish  Sepaiicce. 
Sab-tribe  3.     JjEFIDOzib^. 


597 


Involucre  polypbyllouB,  bracteol©  in  several 

rows.     Colesule  sulcate,  toothed,     .        ,     Lepidozia. 

Involucre  polypbyllous,  bracteolae  scale- 
like, imbricated  on  every  side.  Colesule 
cylindrical,  mouth  compressed.  Pedicels 
not  jointed.  Capsule  4-valved.  Elaters 
two-spired,  naked,  ....    Bazzakia. 

Involucre  polyphyllous,  bracteolsB  bilobed, 
imbricated.  Colesiile  cylindrical,  cleft 
at  side,  mouth  denticulate.  Capsule 
4-valved.     Pedicels  continuous,       .         .     Odontoschisma. 

Involucre  polyphyllous,  bracteolsB  vari- 
ously ciliated  and  lacerate.  Colesule 
sessile,  round,  inflated,  denticulate,  and 
contracted  at  mouth,       ....     Cephalozia. 

Involucre  oligophyllous,  segments  deeply 
divided.  Colesule  sessile,  roundish,  tri- 
lobed,  and  crested  at  mouth,  .         .        .     Lophocolea. 

Involucre  polyphyllous,  larger  than  stem 
leaves,  margins  undulate  and  recurved. 
Colesiile  obovate,  mouth  compressed, 
crenate  denticulate,        ....     PEWKOPHTLLtJM. 

Involucre  polyphyllous,  bracteolaB  scale- 
like, imbricated.  Colesule  cup-shaped, 
bilabiate.     Calyptra  exserted,  •         .        .     Chtlosctphtts. 

'Involucre  oligophyllous,  segments  deeply 
lobed.  Colesule  fusiform,  3-4  cleft  at 
mouth.    Pedicels  inarticulate,  .     Habpanthts. 

Sub-tribe  4.     Saccootnejs. 

Involucral  bracts  wanting.  Colesule  pendu- 
lous from  under  side  of  stem,  smooth, 
mouth  circular,  undulated,      .         .        .     Saccootka. 

Involucral  bracts  wanting.  Colesule  pendu- 
lous, hairy,  attached  by  the  margin  of 
the  apex  to  the  stem,      ....     Kaktia. 

Sub-tribe  5.    Blephaboziks. 

Involucral  bracts  wanting.  Colesule  peduncu- 
late,J  hairy  all  round,  wide-mouthed, 
margin  of  mouth  toothed,        .         .        .     Trichocolsa. 

Involucral  bracts  2-3  lobed  and  ciliated. 
Colesule  club-shaped,  inflated,  mouth  con- 
tracted and  denticulate,  ....    Blsphabozia. 


598 


Proceedings  of  the  Bayai  Irish  Academy. 


Involncre  polypbyllooB,  bracteoUp  imbricated, 
nndivided.  Colesole  sessile,  round,  tri- 
Bulcate,  moutb  denticulate,  .    ILksziaoPHOKA^ 

Involucre  polypbyllous,  bracteols  mucb  cut 
and  connate  at  base.  Colesule  want- 
ing. Capsule  4-valyed,  smooth,  of  thick 
texture, TTmimntTA, 

Involucre  polypbyllous,  bracteolas  imbricated 
all  round,  palmately  cut.  Colesule  sessile, 
roundish,  denticulated  at  mouth,     .        .     Abthslia, 

Involucre  polypbyllous,  bracteols  imbrica- 
ted, articulately  ciliated.  Colesule  sessile, 
erect,  roundish  ovate,  mouth  clothed  with 
long  acute  cilia, Blephasosioiu. 

Sub-tribe  6.     Jungebmaitvixjb. 


Involucre  diphyUous,  segments  bilobed, 
conduplicate.  Colesule  dorsally  com- 
pressed, mouth  truncate,  bilabiate,  at 
first  decurved.  Elaters  bispiral,  attached 
to  centre  of  the  valves,  .... 

Involucre  oligophyllous,  segments  bilobed, 
margin  entire.  Colesule  sessile,  erect, 
round,  mouth  denticulate.  Capsule  coria- 
ceous,     

Involucre  dipbyllous,  bracteolae  convex, 
undivided.  Colesule  laterally  compressed, 
mouth  oblique,  truncate,  toothed  or 
fringed.     Elaters  bispiral,  thread-like,     . 

Involucral bracts  two,  connate  at  base.  Colesule 
ovate  oblong,  laterally  compressed.  Capsule 
4-valved,  of  thick  texture, 

Involucral  bracts  several,  cut  and  bifid,  dis- 
tinct from  the  cauline  leaves.  Colesule 
terminal  on  stem  or  short  branches, 
tubulose,  more  or  less  plaited,  laciniated 
and  contracted  at  mouth.  Calyptra  free 
within  the  colesule,        .... 

Involucre  polypbyllous,  bracteolsB  forming 
an  urceolate  receptacle,  connate  with 
the  colesule  and  connecting  tissue  of  the 
thalamus,     ....  .        . 

Involucral  bracts  double,  larger  than  cauline 
leaves,  inclosing  the  immersed  calyptra. 
Colesule  wanting, 


SCAPAlfflA.. 
DiFLOPBTLLUlC. 

Plaoiochila. 
Mtlia. 


JuKOXBlCAinnA. 
^^ASDIJL. 

Cesia. 


Moore — On  Irish  Hepaticce.  599 

Sub-tribe  7.     Acbobolbrs. 

Inyolucre  terminal  on  torus,  bulbous  and 
rooting  from  underside.  Golesule  want- 
ing. Calyptra  adhering  to  the  bulbous 
base  of  the  receptacle,     ....    Acbobolbus. 

Sub-tribe  8.     Fossoubbonirs. 

Inyolucral  bracts  two,  opposite.  Colesule  want- 
ing. Calyptra  exserted,  cylindrical,  longer 
than  involucral  bracts.  Capsule  of  thick 
texture.     Slaters  single-spired,       .         .     Scalia. 

Involucre  scale-like  or  wanting.  Colesule 
campanulate,  wide-mouthed,  margin  un- 
dulate or  lobed.  Capsule  one-valved, 
globose,  bursting  irregularly,  .        .     Fossohbbonia. 

Involucre  connate  with  the  colesule.  Colesule 
angularly  campanulate,  mouth  wide,  un- 
dulate-dentate. Capsule  sphseroid,  burst- 
ing irregularly,       PSTALOPHTLLtJH. 

Involucre  monophyllous,  cut  and  lacerated. 
Colesule  tubulose,  exserted.  Ctdyptra  irre- 
gularly torn  at  the  apex.  Capsule  oval. 
AndrcBcium  dorsal  on  the  midrib  of  the 
frond, Pallavicdtia.. 

Involucre  undivided,  bladder-shaped,  attached 
to  apex  of  frond.  Colesule  inclosed  within 
the  utricular  involucre.  Androecium  im- 
mersed in  the  frond,  and  covered  with 
dentate  scales, Blasia. 

Involucre  cup-shaped,  toothed,  and  lacerated 
at  the  mouth.  Colesule  wanting.  Calyptra 
oval,  membranous.  Androecium  immersed 
in  the  upper  surface  of  midrib  of  frond,  .     Pellia. 

Sub-tribe  9.     Metzoekiejb. 

Involucre  monophyllous,  scale-like,  ventricose, 
and  two-lobed.  Colesule  wanting.  Calyp- 
tra ascending,  oblong-ovate,  echinate.  In- 
florescence dioecious.  Antheridia  inclosed 
by  a  1 -leafed  involucre  on  the  under  side 
of  midrib, Metzosria. 


600  Proceedings  of  the  Royal  Irish  Academy. 

Involucre  cup-shaped,  short,  lacerate.  Cole- 
sule  wanting.  Calyptra  exserted,  glo- 
bous.  Inflorescence  dioecious.  Capsule 
4-valved.  of  thick  texture.  Elaters  per- 
sistent. Antheridia  immersed  in  recep- 
tacles, proceeding  from  margin  of  frond, .     Eiccabdia.. 

B.     Cleistocabp^. 

Sub-tribe  10.     Sph^bocabfeje. 

Capsule  without  valves,  globular,  free,  im- 
mersed in  the  membranous  frond.  Elaters 
and  Colesule  wanting,     ....     Sphjbbocabfus. 

Section  III.    Anthocebotacrs. 

Capsule  solitary,  filiform,  bivalved,   stalked,  with  a  free  central  pla- 
centation. 

Pamily  1.    AKTHOCEBOXEiE. 

Colesule  tubulose.  Capsule  2-valved,  linear, 
elongate,  pedicelled,  with  a  free  central 
placentation.     Elaters  imperfect,    .         .     Anthocebos. 


Section  I.    MABCHAinriACEiB. 
A.    ScHizocABP^,  Lindberg. 

Family  1.    MABCHAmnEJE. 


Perennial  plants  with  spreading  fronds,  more  or  less  camose,  lying  flat 
on  the  ground,  and  clothed  more  or  less  beneath  with  imbricating 
scales,  which  are  frequently  coloured,  among  which  numerous 
rootlets  issue.  Dioecious  for  the  most  part.  Pemale  receptacle 
raised  on  a  peduncle,  springing  from  near  the  apex  or  back  of  the 
frond,  radiate  or  capitate,  witii  loculi.  Colesules  present  or  want- 
ing.    Male  receptacle  elevated  or  sessile,  smooth  or  hairy. 

MABCHAirriA,  Linneus. 

Male  receptacle  pedunculated,  furnished  with  scales  beneath.  Female 
receptacle  rayed,  involucres  alternate  with  the  rays,  1-3  flowered; 
bivalved.  Coleside  4-5  cleft.  Calyptra  bursting,  remaining  within 
the  colesule. 

Marchantia  polymorphic  Linn.  Fertile  receptacle  deeply  cut,  star-like, 
into  eight  or  ten  divisions.     Male  receptacle  peltate,  undivided. 


Moore — On  Irish  Hepaticw.  601 

Marchantia  polymorpha,  Linn.  Sp.  PL  1603.  Marchant  fil  in  Acta 
Gal.  1713;  Micheli,  Nov.  PL  Gen.  t.  1,  figs.  1,  2,  5;  DiU.  Muse, 
t.  76 ;  and  t.  77,  fig.  7  ;  Engl.  Bot.  t.  100  ;  Muse.  Brit.  ed.  2, 
p.  2,  p.  219.;  Lindenberg,  Synop.  Hep.  Europ.  p.  100 ;  Taylor,  in 
PI.  Hib.  p.  49  ;  Dumortier,  Hepaticee  Europae,  p.  150. 

Hab.  In  moist  situations  generally,  sometimes  in  dry  places.  Espe- 
cially abundant  on  the  surface  mould  of  pots  in  the  Botanic 
Gardens,  where  it  is  frequently  subjected  to  high  temperatures, 
under  which  treatment  both  male  and  female  receptacles  aro 
abundantly  produced. 

CoNocEPHALFS,  Ncck.  Dmrt. 
Marchantia)  sp.  Linn.  Sp.  PL  (1753).  Conocephalus,  Keck.  Elem.  Bot. 
m.,  p.  344  (1790).     Dmrt.  Comm.  p.  115  (1822).     Fegatella, 
Baddi,  in  Op.  Scient.  di  Bologna,  n.  356  (1818).     Nees,  Europ. 
Leberm.,  4,  p.  170. 

DicBcious.  Eertile  receptacle  conical  or  mitriform,  coyering  the  loculi, 
which  are  from  4-5,  and  monocarpous,  opening  with  a  vertical 
fissure.  Golesule  wanting.  Calyptra  bell-shaped,  persistent  in  the 
loculus.  Antheridia  immersed  in  sessile  oval  disks,  near  the  apex 
of  the  frond. 

Conocephalus  eonteuSf  Neck.  Dumort.  Fronds  large,  varying  much 
in  width,  crenate,  undulate  at  the  margins.  **  Buds  appear  in 
winter  between  the  terminating  lobes,  their  margins  involute,  the 
entire  ascending,  recurved,  at  length  opening  into  light,  shining, 
green  fronds.  The  scales  beneath  are  subrotund,  oblique,  slightly 
emarginate.  The  male  receptacle  is  hemispherical  and  smooth 
below,  nearly  flat  above,  immersed  in  a  cavity  of  the  frond,  but 
not  adhering  to  it  except  by  a  central  point  at  the  bottom ;  the 
upper  surface  is  rough,  with  conical  elevations,  the  tops  of  whitish 
antherif  erous  vesicles ;  the  anthers  are  linear,  oblong,  coming  ta 
maturity  the  summer  previous  to  the  ripening  of  the  seeds;  female 
receptacles  fully  formed  in  October  remain  sessile  on  the  f ronda 
until  the  following  February,  when  at  length  the  peduncles 
arise." — Taylor,  in  Flora  Hibemica. 

Marchantia  conica,  Engl.  Bot.  t.  504,  Muse.  Brit.  ed.  2,  p.  221. 
Conocephalus  conicus,  Dumort.  Hepat.  Europ.  p.  155.  Cono- 
cephalus vidgaris,  Bisch.  in  Nov.  Act.  Nat.  Curios.  17,  p.  979. 
Fegatella  conica,  G.  L.  et  N.  Synop.  Hepat.  546 ;  Rabenhor. 
Hep.  Europ.  exsic.  &c.,  299-329. 

Hab.  Damp  shady  places,  where  the  mass  of  fronds  sometimes  spread 
over  several  feet  in  diameter  continuously.  If  taken  in  and  put 
in  a  pot  or  box,  covering  the  surface  with  a  pane  of  glass,  the 
latter  will  after  a  few  days  become  more  or  less  covered  with  the 
antheridia,  which  are  jerked  out  of  their  receptacles  with  such 
force  as  to  make  them  adhere  to  the  covering  glass. 


602  Proceedings  of  the  Royal  Irish  Academy, 

TKKsaauL,  Nees. 

Prcissia,  Corda,  in  Opiz,  Natoralientausch  ( 1 829) ;  Nccs,  Europ.  Lebernu 
(1838). 

Dioecious.  Fertile  receptacle  angularly  hemispherical,  2-4  lohed, 
loculi  attached  to  the  under  side  of  the  lohes,  l--d  fruited,  dehisc- 
ing irregularly.  Colesule  ohconico-campanulate,  4-5  lobed. 
Cdyptra  persistent.  Capsule  pedicelled,  dehiscing  by  revolnte 
segments.  Antheridia  immersed  in  a  peduncled  peltate  recep- 
tacle. 

Premia  eommutata,  Kees.  Frond  oblong,  sinuate,  frequently  bi- 
lobed  at  the  apex,  from  1-3  inches  long,  varying  very  much  in 
width,  accordmg  to  locality.  Fertile  receptacle  peltate,  hemi- 
spherical, with  keel-like  rays.  Capsule  globose,  shortly  pedicellate, 
often  of  a  dark  purple  colour.  Barren  receptacle  peltate,  pe- 
duncled. 

Marchantia  hemisphserica,  Linn.  Fl.  Suec,  No.  1052.  ConocephalTU 
hcmisphaericus,  Dmrt.  Comm.  Bot.,  p.  113.  Marchantia  com- 
mutata,  Lindenb.  Hep.  Europ.,  p.  101.  Preissia  Italica,  Corda,  in 
Opiz,  Natural.,  p.  647.  Preissia  commutata,  Nees,  Europ. 
Leberm.,  4,  117  ;  G.  L.  et  N.  Synop.  p.  539;  Eabenh.  Hep. 
Europ.  exsic.  n.  5,  125,  141,  330,  481  ;  Engl.  Bot.  t.  2545, 
exclude  figs,  at  under  portion  of  plate ;  Caiiington,  Irish  Hepat. 
Trans.  Bot.  Soc.  Edin.  vol.  7,  p.  443. 

Hab.  Fissures  of  damp  rocks,  and  on  damp  ground  in  mountainous 
parts  of  the  country,  particularly  in  limestone  districts ;  occasion- 
ally on  sandy  ground  near  the  sea,  as  at  North  Bull,  near  Dublin. 
Frequent  in  Co.  Galway.  Eocks  above  Eylemore  Castle,  and  by 
the  side  of  the  lake  at  Letterfrack ;  abundant  near  Cong ;  Sillagh- 
braes,  near  Lame,  Co.  Antrim ;  Co.  Kildare ;  Co.  Kerry,  about 
Killamey,  &c.,  &c.  The  variety  minor  on  high  limestone  ridges 
of  the  Benbulben  range,  Co.  Sligo.  Glendine  wood,  Co.  Water- 
ford,  Isaac  Carroll,  Esq. 

DuM0RTi£^,  Nees. 

Marchantia,  Sw.  Prodr.  Fl.  Ind.-Occ.  p.  145  (1788).  Dumortiera, 
Nees,  in  Nov.  Act.  Acad.  Caes.-Lcop.  12,  p.  1,  p.  410  (1823). 
Lunularia?  N.  B.  in  Flora,  13,  p.  2,  p.  401  (1830).  Hygrophila, 
Taylor,  in  Fl.  Hib.  p.  2,  p.  53  (1836).  Spathysia,  Nees,  Nat. 
Eur.  Leberm.  4,  p.  178  (1838).— Lindberg. 

Dicecious.  Male  receptacle  very  shortly  pedunculated,  peltate,  hairy. 
Fertile  receptacle  convex,  pedunculated,  hirsute,  with  scatterwl 
hairs.  Colesule  wanting,  loculi  univalved,  opening  at  the  top  by 
a  vertical  fissure  at  the  outer  extremity.     Frond  without  pores. . 

Dumortiera  irrigua^  Nees.  Fronds  large,  varying  from  2  to  5  inches  in 
length,  and  nearly  an  inch  in  width,  membranaceous,  bilobed, 
margins  slightly  undulate,  of  a  bright  lively  green  colour,  and  with- 


Moore — Oii  Irish  HepaticcB.  603 

out  pores.  Fertile  receptacle  and  involiicres  hairy,  raised  on  rather 
long  peduncles,  which  are  chaffy  at  the  apex.  Male  receptacles 
thick,  camose,  and  nearly  sessile,  beset  with  a  number  of  hair-like 
scales,  which  entirely  cover  the  young  receptacle,  they  are  flat, 
and  recurve  in  a  radiating  spirsd  manner,  tapering  to  a  point. 
These  scale-like  hairs  proceed  from  the  short  peduncle,  and  cover 
the  base  of  the  receptacle. 

Marchantia  irrigua,  Wilson,  in  Hook.  Engl.  Fl.  5,  1,  p.  106.  Hygro- 
phila  irrigua,  Taylor,  in  Fl.  Hib.  p.  54.  Dumortiera,  Reinw.  BL, 
et  Nees,  in  Nov.  Act.  Natur.  Cur.  12,  p.  410 ;  Dumort.  Hepat. 
Europ.  p.  153  (1874). 

Hab.  Sheltered,  shady,  rocky  recesses,  where  water  is  constantly  trick- 
ling over,  or  otherwise  very  moist.  Blackwater  bridge,  near 
Dunkerron,  Dr.  Taylor  (1820).  Tore  waterfall,  near  Killamey. 
Maghanabo  glen,  near  Fermoyle,  Co.  Kerry,  W.  Wilson,  Esq. 
(1829),  who  first  published  the  plant  as  a  native  of  the  British 
Isles,  in  English  Flora  (1833).  Ballinahassig  glen,  near  Cork,  Fl. 
Cork.  Dunscombe's  wood,  I.  Carroll.  Altadore  glen,  near  Delgany, 
Co.  Wicklow,  the  Right  Hon.  Lord  Gough.  We  have  collected  it 
in  the  same  glen,  1872  and  1874;  also  very  sparingly  near  a  small 
waterfall  at  Luggielaw,  Co.  Wicklow.  This  remarkable  plant  is 
very  local  in  Ireland,  and  only  occurs  in  the  warmest  and  most 
sheltered  spots.  It  is  amenable  to  cultivation,  and  under  proper 
management  produces  both  male  and  female  receptacles  rather 
freely,  as  has  been  the  case  in  the  Glasnevin  Botanic  Gardens 
during  a  number  of  years. 

ASTEBELLA,  BcaUV. 

Marchantia,  Linn.  Sp.  PI.  1  ed.,  2,  p.  1138;  Fl.  Lapp.  (1753).  Aste- 
rella,  Beauv.  in  Encycl.  Meth.  Suppl.  1,  p.  502  (1810).  Rebou- 
lia,  Raddi,  in  Opusc.  Scient.  di  Bologna,  n.,  p.  357  (1818). 
Conocephfidus,  Dumort.  Comm.  Bot.,  p.  115  (1822). 

Monoecious.  Frond  rigid,  with  a  broad  and  distinct  midrib.  Fertile 
receptacle  hemispherical,  4-5  lobed,  barbate  beneath.  Colesulo 
wanting.  Calyptra  minute,  lacerate,  persistent  at  the  base  of  the 
capsule.  Capsule  globose,  rupturing  irregularly.  Antheridia  im- 
mersed in  sessile  crescent-shaped  disks. 

Asterella  hemisphBriea,  Beauv.  Frond  bilobed  or  dichotomously 
divided  at  apex,  margins  crenate,  depressed,  more  or  less  ob- 
viously scariose  beneath,  with  purplish  scales.  Fertile  recep- 
tacle barbate  beneath  and  at  apex  of  pedicel,  with  long  white 
silky  hairs.     Antheridia  sessile,  in  crescent-shaped  disks. 

Marchantia  hemisphaerica,  Linn.  Sp.  PL  1604;  Smith's  Engl.  Bot. 
t.  503.  Asterella  hemisphaerica,  Beauv.  Encycl.  Meth.  Suppl. 
p.  502  ;  Lindberg,  in  Not.  pro.  Faun.  Fl.  Fennica,  ix.  p.  286.  As- 
terella hemisphaerica,  Dumort.  Hep.  Europ.,  p.  154  (1874). 


604  Proceedii^s  of  the  Boyal  IrUh  Academy. 

Hab.  On  damp  rocky  places,  walls  of  bridges,  and  on  damp  sandy 
ground.  Bunkerron.  Co.  Kerry,  Dr.  Taylor.  Dingle  bay.  Dr. 
Carrington.  Xear  Cork,  and  Fermoy,  Isaac  Carroll,  Esq.  Abun- 
dant on  the  walls  of  the  bridge  at  Cong,  Co.  Gkdway ;  at  Sillagh- 
braes,  near  Lame,  Co.  Antrim;  on  sandy  ground  at  the  North  Bull, 
near  Dublin,  David  Macardle.  This  plant  is  found  occasionally 
in  the  vicinity  of  its  near  ally  Freissia  commutata,  Nees,  from 
w^ch  the  barbate  under  side  of  the  fertile  receptacle,  and  of  the 
apex  of  the  pedicel,  and  the  sessile  male  flowers  are  ready  and 
obvious  characters  which  will  always  distinguish  it. 

LuNULABiA,  Micheli. 

Lunularia,  Mich.  Nov.  pi.  gen.  p.  4,  tab.  4  (1741);  Raddi,  in  Opusc. 
Scient.  di  Bologna,  ii.,  p.  353  (1818).  Marchantia  cruciata,  linn. 
Sp.  PL  (1753). 

Dioecious.  Fertile  receptacle  deeply  divided  into  narrow  loculi,  loculi 
tubuloso,  opening  with  a  horizontal  fissure.  Capsule  4-valved, 
exscrted.  Mole  receptacle  sessile,  with  a  membranaceous  elevated 
margin. 

Lunularia  erueiata,  Linn.  Dumort.  Fronds  gregarious,  1  to  3 
inches  long,  lobed  and  variously  divided,  waved  and  ele- 
vated at  the  margins,  cuticle  rough,  with  elevated  pores,  under 
surfaces  more  or  less  covered  with  scariose  scales.  GFemmiferous 
scyphi  occur  on  surfaces  of  both  male  and  female  fronds  in  lunu- 
late  or  crescent-shaped  disks,  at  all  seasons  of  the  year.  Fertile 
receptacle  pedunculated,  globular  when  young,  at  length  quad- 
rifid,  the  loculi  of  which  open  by  a  horizontal  fissure,  and 
are  usually  four  in  number.  Colesule  wanting.  Calyptra  rup- 
turing, and  remaining  in  the  bottom  of  the  loculus.  Male  recep- 
tacle sessile,  immersed  in  the  frond  and  situated  at  the  top  of  the 
sinuses.  The  ovate  anthers  are  easily  removed  from  the  mass, 
they  are  ovate,  with  a  grumose  centre,  and  have  a  broad  pellucid 
border. 

Lunularia  vulgaris,  Micheli,  Nov.  Gen.  4,  t.  4.  Marchantia  cruciata, 
Linn.  Sp.  PI.  1604;  Haller,  St.Helv.  (ed.  1768),  tom.  3,  p.  65, 
No.  1888 ;  Huds.  Fl.  Angl.  p.  52 ;  Wither,  Syst.  Arr.  Br.  PI.  od. 
1801,  vol.  3,  p.  869.  Lunularia  vulgaris,  Taylor,  in  Fl.  Hib. 
p.  52  (1836).  L.  cruciata,  Dumort.  Hepat.  Europ.  (1834);  Lind- 
berg,  Hepat.  in  Hibemia  lectin  (1875). 

Hab.  Damp  ground,  and  on  moist  limestone  walls ;  not  very  concunon. 
At  Altadore  glen  I  have  observed  continuous  patches  upwards 
of  a  yard  in  extent,  yet  not  a  single  exserted  female  receptacle  on 
them,  though  both  sexes  occur  there.  I  have  only  once  seen  good 
fertile  receptacles  produced,  which  happened  in  Qlasnevin  Botanic 
Garden.  They  were  sent  to  be  figured  for  the  supplement  to 
English  Botany,  and  a  pretty  good  figure  was  made,  which, 
however,  has  never  been  published. 


Moore — On  Irish  Sepatiop.  605 

Family  2.     Taboioitieje,  Dumort. 

Involucre  bivalved,  sessile  near  the  apex  of  the  frond,  monocarpous. 
Male  receptacle  in  a  terminal  biysdyed  loculus. 

Tabbiokll,  Micheli. 

DicBcious.  Inyolucre  on  the  under  side  of  the  frond,  sessile  near  the 
apex.  Capsule  shortly  pedicellate,  opening  vertically  by  two  mar- 
ginate  vsdves.  Male  receptacle  on  narrow  short  fronds,  near  their 
extremities,  similar  to  the  female  capsules,  but  smaller,  in  which 
the  antheridia  are  imbedded  in  a  camose  disk. 

Targionia  hypophylla,  Linn.  Fronds  closely  packed  together,  some- 
what imbricated,  1  to  2  inches  long,  narrow,  almost  linear 
throughout,  obovate  at  apex,  concave,  margins  purplish  black, 
nearly  entire,  of  a  dull  green  colour,  the  cuticle  rough  with 
raised  pores,  purplish  lunulate  scales  occur  on  each  side  of  the 
midrib  as  in  the  other  Marchantiese.  Fertile  involucre  large, 
compared  with  the  size  of  the  whole  plant,  and  conspicuous  at  the 
apex  of  the  fronds. 

Targionia  hypophylla,  Linn.  Sp.  PI.  1604 ;  Web.  et  Mohr,  Jw.  Germ, 
p.  391,  t.  12;  Engl.  Bot.  t.  287  ;  Lindenb.  Synop.  Hep.  p.  110; 
Hook.  Brit.  Fl.  ii.  p.  55  ;  Raddi,  in  Opusc.  Scient.  di  Bologna,  n. 
359 ;  Taylor,  Fl.  Hib.  pt.  2,  p.  55.  Targionia  Michelii,  Corda,  in 
Opiz,  Natur.  in  Sturm,  Deuts.  Crypt,  fasc.  22,  p.  73,  t.  20;  Nees, 
Europ.  Leberm.,  4,  p.  299 ;  G.  L.  et  N.  Synop.  Hep.  p.  574 ; 
Babenh.  Hep.  Eur.  exsic,  n.  376,  546. 

Hab.  On  warm  dry  rocks.  On  the  cave  hill  at  Belfast,  John  Temple- 
ton,  Esq.  On  dry  limestone  rocks,  Carrigaline,  near  Cork,  Isaac 
Carroll,  Esq.  On  the  warm  basaltic  rocks  at  Deerpark,  Gleaarm, 
Co.  Antrim,  1834,  D.  M.  A  good  specimen  from  the  latter  lo- 
cality is  in  the  Herbarium  of  the  College  of  Science,  Dublin.  This 
plant  is  of  rare  occurrence,  and  very  local  in  Ireland. 

B.     CLEisTOCASPiE,  Liudbcrg. 

Family  3.    Eiccis^,  as  emended,  Lindberg. 

Terrestrial  or  aquatic  plants.  Fruit  immersed  in  the  frond.  Style  pro- 
truded above  the  frond.  Colesule  and  Elaters  wanting.  Spores 
with  pellucid  coats. 

BicciA,  Micheli. 

Eiccia,  Micheli,  Nov.  PI.  Gen.  p.  6,  tab.  4,  fig.  6  (1729);  Linn. 
Sp.  PL,  1  ed.,  2,  p.  1138  (1753).  Riccardia,  B.  Gray,  in  Gray's 
Nat.  Ait.  Brit.  PI.  1,  p.  684  (1821).  Targionia,  Braun,  in  Flora,  4, 
p.  2,  p.  756  (1821).  Ricciella,  Braun,  in  Flora,  4,  p.  2,  p.  756 
(1821).     Bicciocarpus,  Corda,  in  Opiz,  Beitr.  i.  p.  651,  n.  21 


606  Proceedinga  of  the  Royal  Irish  Academy. 

(1829).  SalvinioUa,  Hiibener,  Hep.  Germ.  p.  30,  inter  Synon. 
(1834).— Lindborg. 

1.  Biccia  platica,  Linn.     Frond  stellately   bilobed,  divisions  linear, 

dichotomous,  emarginate,  fleshy,  punctate,  membranaceous  at  the 

margin,  from  ^  to  1  inch  long.  Capsules  immersed  in  the  upper 

side  of  frond,  with  brownish  black  opaque  persistent  styles. 
Eiccia  glauca,  Linn.  Sp.  PL  1605;  Engl.  Bot.  2546;  Lindenb.  Monogr. 

Eicc.  p.  417,  t.  19;  Nees,   Eur.  Leberm.  4,  p.  393  ;  G.  L.  et  N. 

Synop.  Hcpat.  p.  599  ;  Taylor,  in  Fl.  Hib.  n.  p.  70. 
Hab.  On  damp  ground,  where  water  has  stood  during  winter ;  wet 

hedge  banks,  and  scattered  in  more  or  less  abundance  over  the 

whole  of  Ireland. 

2.  Riccia   sorocarpa,    Bischoff.     Frond    solid,   somewhat  trigonous, 

glaucous  green  on  both  surfaces,  subdichotomous,  divisions  thick 
and  fleshy,  margin  glabrous,  inflexed  when  dry,  upper  surface 
canaliculate  when  dry,  mid  vein  distinct.  Fruit  immersed  when 
young,  at  length  bursting  the  epidermis,  and  allowing  the  spores 
to  escape. 

Eiccia  sorocarpa,  Bisch.  in  Nov.  Act.  Nat.  Cur.,  17,  p.  1053  to  71, 
f.  11;  G.  L.  et  N.  Synop.  Hepat.,  p.  600;  Eabenhor.  Hep. 
Europ.  cxsic.  n.  28,  543 ;  Dr.  Braithwaite,  in  Grevillea,  for  March 
ri873),  p.  144;  Dr.  Carrington,  in  Grevillea,  for  December 
(1873),  p.  86,  pi.  18;  Professor  Lindberg,  in  Hepat.  in  Hibem. 
lect»,  p.  471  (1874). 

Hab.  Fissures  of  moist  walls,  &c.  On  an  old  wall  near  Dingle,  Co. 
Kerry,  July  (1873),  Professor  Lindberg. 

EiocnxLA,  Al.  Braun. 

Eiccia,  Sp.  L.  Eicciella,  Braun,  in  Bot.  Zeit.  (1821);  Lindenb.  Synop. 

Hepat. ;  Dumort.  Hepat.  Europ.  (1874). 
"  Fruit  globose,  protuberant  from  the  lower  surface  of  the  frond,  and 

inserted  on  it." — Dumort.     Frond  spongy,  mixed  with  large  air 

cavities,  floating. 
Ricciella  fluitaiM,  Al.  Braun.      Frond    linear,  plane,  dichotomonsly 

forked,  radiating  in  a  stellate  manner,  thickened  at  the  apex, 

emarginate  and  cavernous.      Fruit  protruding   from  the  lower 

surface  of  the  frond. 
Eiccia  fluitans,  Linn.  Sp.  PI.  1606;  Neeo,  Eur.  Leberm.  4,  p.  439; 

G.  L.  et  N.  Synop.  Hepat.  p.  610  ;    Lindenberg,  Monogr.  Eicc, 

p.  443,  t.  24-25;  Eabenh.  Hepat.  Europ.  exsic.  n.  82,  296,  340; 

Engl.  Bot.  t.  251 ;  Hooker  et  Taylor,  Muscol.  Brit.ed.  2,  p.  213; 

Sullivant's  Musci  et  Hepat.  U.S.  p.  684,  tab.  6.  Eicciella  fluitans, 

Lindenb.  Synop.  Hepat.  p.  115;  Hiibener,  Hepat.  Germ.  p.  31 ; 

Dumort.  Hepat.  Europ.  p.  171. 
Hab.  Stagnant  pools  and  still  places  by  river  sides;  generally  floating 


Moore — On  Irish  Hepaticae.  607 

among  spedes  of  Lemna  and  other  aqnatics.  Not  nnfrequent  in 
ditches  near  the  Shannon,  Co.  Limerick;  by  the  side  of  the  Bann 
River,  above  Drogheda ;  still  ditches  near  Lough  Neagh,  where 
the  canal  joins  the  Longh  at  Lnrgan. 

BioaoGABPus,  Gorda. 

Eiccia,  Linn.  Syst.  Nat.  Kicciocarpus,  Gorda,  in  Opiz,  Natnr.  p.  651 
(1829).  Hemiseuma,  Bischoff,  ex  Nees,  Europ.  Leberm.,  4,  p. 
419  (1838). 

'^  Fruit  immersed  in  the  frond,  and  not  protruding  in  either  surface, 
at  length  bared  by  an  incision  in  the  central  groove." — ^Dum. 

Eieeioearpus  natans,  Corda.  Frond  inversely  heart-shaped,  grooved 
in  the  centre  of  upper  surface,  from  |  to  f  of  an  inch  wide, 
clothed  beneath  and  at  the  margin  with  long,  purplish,  pendent 
rootlets,  which  latter  are  fringed  with  slender  ciUa-Hke  serratures. 

Kiccia  natans,  Linn.  Syst.  Nat.  ed.  v.  12,  p.  2  ;  Engl.  Bot.  t.  252 ; 
Weber,  Prodr.  Hepat.  p.  117  ;  Hook,  et  Taylor,  Muscol.  Brit  ed. 
2,  p.  214 ;  Lindenb.  Synop.  Hqp.,  p.  121 ;  Mongr.  Eicc,  475, 
t.  31-32  ;  Nees,  Eur.  Leberm.  4,  p.  419;  G.  L.  et.  N.,  Synop. 
Hep.,  p.  606  ;  Rabenhor.  Hep.  Eur.  exsic.  n.  2,  140,  499 ; 
Sullivant's  Musci  et  Hepat.  U.  S.  p.  684,  tab.  6.  Ricciocarpus, 
Gorda,  in  Opiz,  Naturalientausch,  p.  651  (1829)  ;  Dumort.  Hepat. 
Europ.  p.  172  (1874). 

Hab.  Stagnant  pools  and  ditches.  Rare  in  Ireland.  Abundant  in  a  large 
boggy  pool  about  half-way  between  Drogheda  and  Navan,  near 
the  Railway,  right-hand  side  going  from  Navan  to  Drogheda j 
ditch  by  the  side  of  the  Shannon,  near  Portumna,  Go.  Galway. 
Ditches  near  Passy,  Co.  Limerick,  Dr.  "W.  H.  Harvey.  This 
and  the  preceding  species  have  been  cultivated  in  Glasnevin  Bo- 
tanic Gardens,  floated  in  pans  of  water,  in  which  condition  they 
multiply  quickly  and  fruit  freely. 

Although  I  have  followed  Dumortier  in  his  Hepaticse  EuropsB  in  adopt- 
ing the  genera  Ricciocarpus,  Gorda;  and  Ricciella,  Al.  Braun; 
yet  the  characters  as  given  by  these  authors  for  separating  them 
from  Riccia,  Linn.,  &c.,  seem  to  me  too  slight  for  constructing 
good  genera  on. 

SkCHON  II.   JinfOERMAXNIACEJe. 
A.   ScmZOCABFjE. 

a.  Ahomooamje. 

"  Prothallium  disciform.  Stems  more  or  less  regularly  pinnate,  more 
rarely  dichotomously  branched.  Leaves  incubous,  conduplicate, 
the  hinder  lobe  smallest — saccate,  galeate,  cucullate  or  flattish. 
Amphigastria  mostly  present,  rarely  wanting.      Inflorescence 

r*  I.  A.  FBOC.,  8EB.  U.,  VOL.  u.,  scisircB.  3  N 


608  Proceedings  of  the  Royal  Irish  Academy. 

dioecious,  autoeciouB,  more  rarely  paroecious.  Perichsetium  apical, 
or  from  the  posterior  face  of  the  stem,  next  its  side  above  the 
axil  of  the  leaves,  as  a  proper  branchlet,  never  from  the  axil  of 
the  amphigastrium.  Colesnle  generally  small,  5-plicate,  and  some- 
times winged  or  compressed,  rarely  round  or  densely  plicate, 
mouth  often  narrow  and  beak-shaped,  rarely  none.  Set®  short  or 
slender.  Capsule  minute,  globose,  mostly  very  thin  and  pellucid, 
as  if  composed  of  few  strata,  generally  cleft  to  the  middle,  valves 
erect.  Elaters  1-  or  2-spired,  adhering  in  pencil-like  tufts  to 
the  apex  of  the  valves  or  to  the  interior  face  of  the  capsule. 
Androecia  lateral  to  the  stem,  like  the  perichstia.  Antheridia 
two,  or  solitary,  fixed  in  the  axils  of  concave  bracts,  rarely  in  the 
axils  of  leaves  or  perichaetial  bracts." — ^Lindberg. 

Sub-tribe  1.  Fbullakiba. 

1.  Ebttllakia,  B4iddi. 

Jungermannia,  Rupp.  PI.  Jen.  1  ed.,  p.  346  (1718).  Heimea,  Neck. 
Elem.  Bot.  3,  p.  338  (1790).  Jungermannia,  Hooker,  Brit. 
Jung.  (1816).  Prullania,  Raddi,  in  Mem.  Soc.  Modena,  18,  p. 
20,  tab.  2  (1818).  Salviata,  B.  Gray,  in  Gray's  Kat.  Arr.  Brit. 
PI.  p.  687  (1821).  Jubula,  Dumort.  Comm.  Bot.  p.  112  (1823). 
Lejeunea,  Corda,  in  Opiz,  Beitr.  1,  p.  652,  n.  4  (1829). 

Leaves  incubous,  distichous,  lower  segment  saccate.  Colesnle  com- 
pressed, trigonous,  mouth  constricted,  mucronulate.  Elaters 
with  single  spires. 

a,  JuBULOTTPus,  Dumortier. 

1.  Fndlania  Sutchinsia  (Hook.),  Kees.  AutoBcious.  Stems  csespitose, 
prostrate,  from  one  to  two  inches  long.  Leaves  unequally  2- 
lobed,  the  lower  lobe  saccate,  the  upper  ovate,  spinidose-den- 
tate  at  the  margin.  Amphigastria  rounded  at  the  base,  acutely 
bifid,  segments  dentate.  Colesule  obcordate,  slightly  trigonal. 
Antheridia  on  short  slender  ramuli,  proceeding  from  the  inferior 
face  of  the  stem. 

Jungermannia  Hutchinsiee,  Hook.  Brit.  Junger.,  tab.  1 ;  Engl.  Bot. 
tab.  2480.  Salviata  Hutchinsiae,  B.  Gr.  in  Gray's  Arr.  Br.  PI.  1, 
p.  688.  Jubula  Hutchinsiae,  Dumort.  Comm.  p.  112;  Syll. 
Jung.,  p.  36  ;  Hepat.  Europ.,  p.  26.  Prullania  Hutchinsiae, 
Nees,  Europ.  Leberm.  3,  p.  240;  G.  L.  et  N.  Synop.  Hepat., 
p.  426 ;  Rabenhor.  Hepat.  Europ.  exsic.  n.  208,  477. 

Hab.  On  wet  rocks  near  waterfalls.  Bantry,  Miss  Hutchins.  Killamey, 
Cromaglaun,  &c. ;  caves  near  the  sea,  Dingle  Bay,  Kerry.  Ballin- 
hassig  glen,  and  near  Kinsale,  Cork,  Isaac  Carroll,  Esq.  Fissures 
of  wet  rocks  by  the  lake  near  Letterfrack,  Co.  Galway  (1874). 


Moore — On  Irish  Sepatica.  609 

Far.  p.  inUgHfolia,  Nees  [Plate  46]. 

This  appears  to  me  a  very  distinct  plant  from  the  typical  f onn  of  the 
species.  It  difPers :  1,  in  the  leayes  being  more  obovate  and 
less  spinulose  at  their  margins  ;  2,  in  the  absence  of  an  auricle  to 
the  margin  of  the  leaf ;  3,  in  the  amphigastria  being  smaller,  and 
the  margins  of  their  lobes  more  entire ;  4,  in  the  smaller  size  of 
the  plant,  and  its  olive-green  colour. — The  colesules  are  terminal 
on  the  main  branches,  and  on  their  middle.  They  are  trigonal 
as  in  the  typical  form.  The  androecium  consists  of  small  amenta, 
which  proceed  from  the  middle  of  the  stem  branches  (autoecious). 
This  remarkable  plant  was  collected  by  Professor  Lindberg  and 
myself  at  Connor  Hill,  in  July,  1873. 

The  few  specimens  I  had  were  imperfect,  and  without  colesules. 
In  1875  one  of  our  garden  assistants,  Mr.  D.  Macardle,  collected 
it  in  larger  quantity  in  Maghanabo  glen,  near  Castlegregory, 
Co.  Kerry,  growing  over  the  fronds  of  Dumortiera  irrigua.  The 
plants  he  brought  were  more  perfect,  having  both  the  gynoecium 
and  androecium  in  good  condition.  I  have  carefully  examined  a 
number  of  these,  and  cannot  fibid  on  any  of  them  auricles  to  the 
leaves.  On  some,  I  have  observed  the  slightest  folding-in  of  a 
minute  tooth-like  portion,  where  the  auricle  ought  to  be.  The 
amphigastria  are  minute,  not  more  tjian  half  the  size  they  are  in 
the  typical  form.  I  have,  however,  no  doubt  that  our  plant  is  of 
the  same  kind  as  that  noticed  (G.  L.  et  N.  Synop.  Hep.  p.  426) 
as  having  been  found  in  the  island  of  Java  by  Blume;  the  note  of 
observation  by  Dr.  Gottsche,  which  is  appended,  having  reference 
to  his  Java  specimens,  confirms  me  in  this  opinion.  Professor 
Lindberg,  in  lus  paper  on  Hepaticse  collected  in  Ireland,  states  that 
this  plant  is  found  in  North  America  and  in  the  island  of  Java. 

ft.  AscoLOBiTJM,  Dumortier. 

2.  Frullania  dilatata^xtm,),  Dumort.  Stems  prostrate,  in  dense  purp- 
lish patches.  Leaves  incubous,  unequally  2-lobed,  rotundate, 
entire,  the  lower  lobe  small,  saccate.  Amphigastria  roundish, 
slightly  notched  at  the  apex.  Colesule  obcordate,  tuberculated, 
angular  on  the  under  side. 

Jungermannia  dilatata,  Linn.  Sp.  PI.  p.  1 600  ;  Hook.  Brit.  Jung.  tab. 
3;  Tayl.  in  FL  Hib.  p.  2,  p.  67  ;  Lindb.  Syst.  Hepat.,  p.  17  ; 
De  Notar.  Prim.  Hep.  Ital. ,  p.  1 0 .  Frullania  minor,  Eaddi,  Jung,  in 
Mem.  Modena,  18,  p.  21,  t.  2,  fig.  3 ;  Dumort.  Rev.  Jung.  p.  13 ; 
Hep.  Europ.,  p.  27  ;  Kees,  Europ.  Leberm.,  3,  p.  217  ;  G.  L.  et 
N.  Synop.  Hep.,  p.  416. 

Hab.  On  the  trunks  of  trees  and  on  rocks.  Very  frequent  in  Ireland. 

5.  Frtdlaniafragilifoliaf  Taylor.  Stems  from  J  to  J  of  an  inch  long,, 
growing  in  thin  prostrate  patches,  of  a  deep  brown  colour.  Leaves 
incubous,  slightly  raised  in  their  centres,  oblongo-rotundate,  en- 

3n2 


610  Proceedings  of  the  Royal  Irish  Academy. 

tire,  amicdelles  oblong,  helmet-like.     Ampliigastria  ovate  and 

bifid  at  the  point,  plane  at  the  margin.   Involucral  bracts  obtuse, 

with  few  teeth.  Colesule  obovate-cordate. 
Frullania  fragilifolia,  Taylor,  in  Trans.  Bot.  Soc.  Edin.  2,  p.  43 ;  G.  L. 

et  N.  Synop.  Hepat.,  p.  437 ;  Spruce,  Muse,  et  Hepat.  Pyren. 

in  Trans.  Bot.  Soc.  Edin.  3,  p.  215 ;  Cooke's  Brit.  Hepat.  p.  21, 

figs.  160,  161 ;  Eabenh.  Hep.  Europ.  exsic.  n.  180,  200  et  226. 
Hab.  Shady  rocks  and  trees.      Kot  unfrequent  in  the  Killamey 

woods.    Dunkerron,    Dr.    Taylor.     On  boulders,   Bantry   Bay, 

Glengariff,  Dr.  Carrington. 

4.  Frullania  tamarisci  (Mich.,  L.),  Dumort.    Stems  spreading  in  largo 

patches,  two  to  four  inches  long,  of  a  brownish  colour.  Leaves 
incubous,  closely  and  distichously  arranged,  unequally  2-lobed,  the 
upper  ovate-rotundate,  the  lower  smaller  and  saccate.  Amphigas- 
tna  obscurely  notched  at  the  apex,  subquadrate.  Colesule  ovate, 
smooth,  triangular,  attenuated,  mouth  dentate. 
Jungermannia  tamarisci,  L.  Sp.  PL  1  ed.,  2,  p.  1134;  Hook.  Brit. 
Jung.  t.  6 ;  Taylor,  in  Fl.  Hib.,  p.  68.  Frullania  major,  Raddi, 
in  Att.  Soc.  8c.  Modena,  18,  p.  20.  Salviatus,  B.  Gr.  in  Gray's 
Arr.  Brit.  PI.  1,  p.  687.  Frullania  tamarisci,  Dumort.  Bev. 
Jung.,  p.  13;  Hepat.  Europ.,  p.  28;  G.  L.  et  K  Synop. 
Hepat.,  p.  438.  Var.  )8.  microphylla,  Gottsche,  Rabenh.  Hep. 
Europ.  exsic.  n.  209. 

Hab.  On  the  smooth  bark  of  trees.  Old  Weir  Bridge,  Co.  Kerry, 
Dr.  Carrington. 

5.  Ihdlania    yermana,    Taylor.       Stems    procumbent,    bipinnatc, 

branches  complanate,  short-spreading.  Leaves  imbricated,  ovate- 
roundish,  entire,  auricles  oblong-ovate,  ventricose.  Amphi- 
gastria  obovate,  margins  recurved,  cleft  at  the  apex.  Involuci-al 
bracts  entire.   Coleside  tubular,  oblong-ovate. 

Jungermannia  germana,  Taylor,  in  Trans.  Bot.  Soc.  Edin.,  vol.  2, 
p.  43.  Frullania  germana,  G.  L.  et  N.  Synop.  Hepat.,  p.  450 ; 
Dumort.  Hepat.  Europ.,  p.  29.  F.  tamarisci,  var.  c.  germana, 
Carring.  Irish  Hepat.  p.  457. 

Plants  of  this  species  are  generaUy  larger,  and  of  a  lighter  brown 
colour  than  those  of  F.  tamarisci.  The  involucral  bracts  are  en- 
tire. The  leaves  are  destitute  of  the  line  of  moniliform  cells, 
which  are  so  obvious  in  F.  tamarisci,  and  the  cells  in  them  are 
larger,  with  the  walls  thicker. 

Hab.  On  rocks  and  on  trees.  Frequent  in  the  County  of  Kerry; 
Co.  Donegal ;  Lough  Bray,  Wicklow. 

Lejeunea,  Libert. 

Jungermannia,  Mich.  Nov.  PI.  Gen.,  p.  9,  t.  6,  figs.  19,  20 
(1729);  Hooker,  Brit.  Junger.  (1816).     Lejeunea,  Mademoiselle 


Moore — On  Irish  HepatictB,  611 

Libert,  in  Ann.  Gen.  Sc.  Phys.  6,  p.  372,  tab.  97  (1820).  Pandul- 
phinia,  B.  Gray,  in  Gray's  Nat.  Arr.  Br.  PL,  1,  p.  283  (1821). 
Marchesinius,  B.  Gray,  /.  e,  p.  689.  Phragmicoma,  Dumort.  Comm. 
Bot,  p.  112  (1823).  Colura,  Dumort.  Recueil,  1,  p.  12  (1835). 
iJolcsule  obovate,  angled  or  roundish,  moutb  contracted  and  dentate. 
Capsule  1-valved,  deeply  cleft,  pedicels  articulated.  Elaters 
doubly  spired,  adhering  to  the  apices  of  the  segments  of  the 
capsules.     Antheridia  in  a±ils  of  pericheetial  leaves. 

Lejeuneottpus,  Dumort.  Lindb. 

a.  Leavei  acuminaU,  or  acute  at  their  points, 

1.  Lefeuneacalt/ptrifolia  (Rook,),  DnmoTt,     Dioecious.     Stems  creep- 

ing, in  very  minute  compact  tufts.  Leaves  2-lobed,  the  upper 
lobe  large  and  peculiarly  formed,  resembling  in  no  small  degree 
the  calyptra  of  some  mosses,  the  lower  obtusely  quadrate,  invo- 
lute. Colesule  lateral,  oblong,  flat  campanulate,  5-toothed,  and 
slightly  contracted  at  the  mouth.  Antheridia  from  side  of  stem, 
not  in  axils  of  the  leaves. 

Jungermannia  calyptrifolia.  Hook.  Brit.  Jung.,  t.  43;  Engl.  Bot., 
2538 ;  Lindenb.  Synop.  Hepat.,  p.  24;  Ekart,  Synop.  Jung.  Germ., 
p.  59,  1. 10,  f.  86.  Lejeunea  calyptrifolia,  Dumort.  Comm.  Bot., 
p.  Ill;  G.  L.  et  IS,  Synop.  Hepat.,  p.  403;  Cooke,  Brit. 
Hepat.,  p.  21,  fig.  156.  Colura  calyptrifolia,  Dumort.  B«v. 
Jung.,  p.  12 ;  Hepat.  Europ.,  p.  17. 

Hab.  On  trees,  stems  of  furze,  heath,  and  rarely  on  bare  rocks. 
Glengariff,  Miss  Hutchins.  Near  Dunkerron,  Dr.  Taylor,  in  Mora 
Hibemica.  Tore  Mountain,  on  the  stems  of  pines,  "W.  Wilson, 
and  Dr.  Carrington.  On  the  bare  rock  at  Connor  Hill,  Kerry, 
where  it  was  observed  in  some  quantity  by  Dr.  Lindberg  and 
myself,  in  July,  1873 ;  also  near  the  police  barrack,  Upper  Lake, 
Killamey,  on  rocks,  during  same  month. 

2.  Lejeunea  hamatifolia  (Hook.),  Dumort.     Autoecious.     Stems  very 

slender,  minute,  creeping  and  adhering  closely  to  the  surfaces  on 
which  they  grow.  Leaves  unequally  2-lobed,  the  lower  about 
half  the  size  of  the  upper,  the  latter  acuminated,  incurved, 
coarsely  serrated.  Amphigastria  small  and  bidentate.  Colesule 
pentagonal,  with  crested  ridges. 

Jungermannia  hamatifolia.  Hook.  Brit.  Jung.,  t.  51 ;  Engl.  Bot.,  t. 
2592 ;  Lindenb.  Synop.  Hep.,  p.  23 ;  Taylor,  Fl.  Hib.,  p.  2,  p. 
67.  Lejeunea  hamatifolia,  Dumort.  Comm.  Bot.,  p.  Ill;  Syll. 
Jung.,  p.  52,  et  Hepat.  Europ.,  p.  20;  G.  L.  et  N.  Synop. 
Hepat.,  p.  344;  Rabenh.  Hepat.  Europ.  exsic.  n.  215-476. 

Hab.  On  the  trunks  of  trees,  and  on  bare  rocks.  This  species,  which 
is  so  plentiful  in  the  Killamey  woods,  is  rare  on  the  eastern 
coast  and  northern  counties.      1  collected  it  at  Glenarm,  and 


612  Proceedings  of  the  Royal  Irish  Academy. 

Collin  Glen,  Co.  Antrim,  in  1837  ;  very  fine  and  bearing  capsules 
on  trees  in  Glenfam  demesne,  Co.  Leitrim,  1875.  Dr.  Taylor 
observed  it  at  "Woodlands,  near  Dublin.  At  Powerscourt,  Wick- 
low  ;  on  Connor  Hill,  Kerry,  it  grows  on  the  bare  rock,  along 
with  L.  calyptrifolia,  both  of  which  were  collected  in  company 
with  Dr.  Lindberg,  July,  1873 ;  Kylemore  Castle  demesne,  Co. 
Galway,  1874.     Near  Cork,  Isaac  Carroll,  Esq. 

3.  Lejeunea  echinata  (Hooker),    Taylor.    Autoecious.    Stems  hair-like, 

very  minute.  Leaves  ovate,  concave,  acuminate,  spinulose-den- 
tate,  saccate  at  the  base.  Colesule  roundish,  pentagonal.  Anthe- 
ridia  singly  or  in  pairs  in  axils  of  the  perichsetial  leaves. 
Jungermannia  hamatifolia,  p,  echinata.  Hook.  Brit.  Jung.  51.  Lejeunea 
calcarea,  Libert,  Ann.  Gen.  Sc.  Phys.,  6,  p.  373,  t.  96,  f .  1  ^ 
Dumort.  Syll.  Jung.,  p.  33,  t.  1,  f.  3,  et  Hepat.  Europ.,  p.  19; 
Nees,  Europ.  Leberm.  3,  p.  293;  G.  L.  et  K.  Synop.  Hepat., 
p.  544;  Rabenhor.  Hep.  Europ.  exsic.  n.  46,  283,  323; 
Cooke,  Brit.  Hepat.,  p.  20,  fig.  150.  Jungermannia  echinata, 
Tayl.  in  Spruce's  Muse,  of  Teesd.,  Trans.  Bot.  Soc.  Edin.  2,  p.  88. 

Hab.  On  limestone  rocks.  Woodlands,  Dublin,  Dr.  Taylor.  Muck- 
ross  demesne,  Killamey,  growing  on  the  stems  and  leaves  of 
Thamnium  alopecurum.  Dr.  Carrington.  In  same  situation  and 
on  same  moss.  Dr.  Lindberg  (1873.)  Limestone  rocks,  near 
Tralee  (1875).- 

4.  Lejeunea  ovata,   Taylor.     DioBcious.    Stems    creeping,   branched. 

Leaves  incubous,  obliquely  set  on  the  branches,  and  close  toge- 
ther, margins  not  serrated,  bilobed,  the  larger  lobe  ovate-acute,, 
saccate,  and  inflated.  Amphigastria  small,  obcordate,  notched  at 
apex,  segments  obtuse.  Colesule  obovate,  acute,  and  angled  ftt 
the  apex. 

Jungermannia  ovata,  Dicks.  PL  Crypt.  Brit.  3,  p.  11,  tab.  8,  f.  6. 
Jungermannia  serpyllifolia,  )8.  ovata.  Hook.  Brit.  Jung.,  n.  42. 
Lejeunea  ovata,  Taylor,  in  G.  L.  et  N.  Synop.  Hep.,  p.  376 ; 
Spruce,  Muse,  et  Hepat.  Pyren.  in  Trans.  Bot.  Soc.  Edm.  3,  p. 
212;   Dumort.  Hepat.  Europ.,  p.  20. 

Hab.  On  the  moss-covered  trunks  of  trees,  and  also  on  the  bare  bark. 
Very  abundant  at  Cromaglaun,  Kerry,  and  through  all  the 
Killamey  district.  Kear  Belfast,  Dr.  Dickie.  More  sparingly 
in  the  northern  and  eastern  counties.  Mr.  Spruce  has  pointed 
out  good  distinguishing  characters  between  this  and  L.  hamati* 
folia  in  the  work  quoted. 

h.  Leasee  obtusely  rotundate, 

5.  2^'euneamtcro8copioa,Ta,yloT,    Paroecious.    Plant  very  minute,  and 

stain-like.  Leaves  ovate-lanceolate,  concave,  acute,  bluntly 
dentate  at  the  margin,  patent.  Colesule  obovate,  contracted  at  tho 
mouth,  subdenticulate. 


Moore — On  Irish  Hepaticce.  613 

Jungcrmannia  microscopica,  Taylor,  in  PI.  Hib.  2,  p.  59;  Hook. 
Journal  of  Botany,  4,  p.  97,  t.  20 ;  Kees,  Europ.  Leberm.  3,  suppL, 
p.  566.  Lejeunea  microscopica,  Taylor,  in  G.  L.  et  N.  Synop. 
Hepat.,  p.  345 ;  Gaiiington,  in  Trans.  Bot.  Soc.  Edin.  7,  p.  3, 
p.  456;  Cooke,  Brit.  Jung.,  p.  20,  fig.  151;  Dipnort.  Hepat. 
Europ.,  p.  19. 

Hab.  Parasitic  on  mosses,  ferns,  and  dead  stumps  of  trees.  Croma- 
glaun,  Kerry,  Dr.  Taylor  and  Dr.  Carrington.  On  Trichomanes 
radicans.  Purple  Mountain,  Killamey;  glen  at  Brandon  Moun- 
tain, &c.  This  very  minute  plant  appears  like  a  slight  green 
stain  on  the  plants  on  which  it  grows,  and  is  of  frequent  occur- 
rence, though  often  oTerlooked.  It  has  not,  however,  we  be- 
lieve, been  observed  hitherto  out  of  the  County  of  Kerry.  To 
the  unaided  eye  it  has  no  appearance  of  an  organised  plant,  but 
it  is  easily  detected  when  placed  under  the  microscope,  and  mois- 
ture applied.  The  minute  stems  float  and  spread  themselves  and 
so  do  the  leaves.  It  is  one  of  the  most  distinct  species,  and  can- 
not be  mistaken  or  confounded  with  any  of  the  others. 

6.  Z&feunea  ineonspicua    (Mich.,   Eaddi),    De  Kotaris.     AutoeciouB. 

Stems  very  minute,  hair-like.  Leaves  distant,  ovate-rotundate, 
entire,  convex.  Amphigastria  none.  Colesule  axillary,  turban- 
shaped,  pentagonal  and  plicate. 

Jiingermannia  ineonspicua,  Raddi,  in  Att.  Soc.  Modena,  18,  p.  34,  t.  5, 
fig.  2.  Jungermannia  minutissima,  Taylor,  in  Trau'B.  Bot.  Soc. 
Edin.  Lejeunea  Taylori,  Spruce,  in  Trans.  Bot.  Edin.  vol.  3, 
p.  12.  Lejeunea  minutissima,  G.  L.  et  N.  Synop.  Hep.  p.  387; 
Dumort.  Hepat.  Europ.,  p.  18. 

Hab.  On  stems  of  heath  and  furze,  also  on  trunks  of  trees.  Near 
Kenmare,  Dr.  Taylor;  and  other  parts  throughout  the  counties  of 
Kerry  and  Cork.  Not  very  rare,  but  chiefly  confined  to  the  south- 
em  counties.  This  minute  plant,  which  can  only  be  well  dis- 
tinguished from  Lejeunea  minutissima.  Smith,  by  wanting  am- 
phigastria, was  mixed  up  with  that  species,  until  Dr.  Taylor 
published  characters  for  each,  and  separated  them.  Dr.  Spruce 
has,  .however,  shown  that  Dr.  Taylor  was  in  error,  in  supposing 
the  exstipulaceous  plant  to  be  Smith's  plant.  See  foot-note  in 
Trans.  Bot.  Soc.  Edin.  vol.  iii.,  p.  212. 

7.  Lejmnea  fninuiUsima  (Smith),  Dumortier.    Dioecious.     Stem  creep- 

ing, capilliform.  Leaves  indistinctly  2-lobed,  lower  lobe 
minute,  rather  distantly  placed  on  the  stem,  ovate-obtuse.  Am- 
phigastria bifid.  ColesiUe  lateral,  obovate-rotundate,  pentago- 
nal and  contracted  at  the  mouth. 

Jungermannia  minutbsima.  Smith,  Engl.  Bot.  t.  1633;  Hook.,  Brit. 
Junger.  t.  52.  Jungermannia  ulicina,  Taylor,  in  Trans.  Bot.  Soc. 
Edin.  1,  p.  115.   Lejeunea  minutissima,  Dumort.  Syll.  Jung.  p.  33, 


614  Proceedings  of  the  Royal  Irish  Academy. 

et  Hepat.  Europ.  p.  19 ;  Taylor,  in  G.  L.  et  N.  Synop.  Hq>. 
p.  387  ;  Rabenhor.  Hep.  Europ.  exsic.  n.  322 ;  Cooke,  Brit  Jong, 
p.  20,  fig.  155. 

Hab.  On  the  Btenu  of  trees  and  on  moBsea.  Abundant  in  the  Kil- 
lamey  w.oods,  and  other  parts  of  Kerry  and  Cork ;  Kylemorc 
Castle,  Co.  Galway ;  Collin  Glen,  Belfast ;  Woodlands,  Ihiblin ; 
Lnggielaw,  and  Powerscourt,  Wicklow;  Glenfam  demesne,  Co. 
Leitrim. 

8.  Lejeunsa  i&rpyUifolia  (Mich.,  Dicks.),  Libert.  AntoBcions.  Stems 
prostrate  or  creeping,  pinnately  branched.  Leaves  incubons, 
2-lobed,  lobes  unequal,  the  upper  being  much  the  largest  and 
of  a  roundish-oblong  form,  the  lower  much  smaller,  and  invo- 
lute. Amphigastria  wide,  roundish,  deeply  bifid.  Colesule  some- 
what pear-shaped  or  obovate,  mouth  angled  and  protruding. 

Jungermannia  scrpyllifolia,  Dicks.  Fl.  Crypt.  Brit.  4,  p.  19;  Engl. 
Bot.  t.  2537  (excl.  synon.) ;  Hook.  Brit.  Jung.  t.  42 ;  Lindenb. 
Hep.  Europ.  p.  21.  Lejeunea  serpyllifolia.  Lib.  in  Ann.  Gen. 
8c.  Phys.  6,  p.  374 ;  Dumort.  Comm.  Bot.  p.  3 ;  Syll.  Junjj. 
Eur.  p.  33,  et  Hepat.  Europ.  p.  21 ;  G.  L.  et  K.  Synop.  Hepat. 
p.  374 ;  Rabenhor.  Hep.  Eur.  exsic.  n.  435. 

Hab.  On  trunks  of  trees  covered  with  the  larger  mosses,  &c.,  and  on 
damp  banks  among  mosses.  Generally  distributed  through 
Ireland. 

Far.  p.  thymifolia,  Carrington,  in  Trans.  Bot.  Soc.  Edin.  7,  p.  456. 
**  Leaves  larger,  elliptic-ovate,  very  convex,  closely  imbricated 
inflexed." 

Var»  y.  heUrophyllay  Carrington.  "  Branches  attenuate,  microphyllons. 
Leaves  plane,  lobule  obsolete,  variously  shaped,  distant,  chloro- 
phyllose. 

Hab.  On  wet  shady  rocks.  0' Sullivan's  cascade,  and  near  Tore  Water- 
fall, Dr.  Carrington. 

Var.  p.  cdvifolia  (Ehrh.),  Lindb.  "Leaves  crowded,  front  lobe 
convex,  incumbent  when  dry,  more  spreading  from  the  basal  sac, 
generally  much  decurved,  oblique,  broadly  ovate,  very  blunt, 
yet  sometimes  narrowed  distinctly  at  apex,  never  pointed,  very 
entire,  basal  lobe  3-5  times  smaller,  cells  very  full  of  chlo- 
rophyll and  thickened,  trigonal  spaces  distinct.  Amphigastria 
subadpressed,  equally  large  or  larger  than  the  hinder  lobe,  con- 
vex, otherwise  as  in  type.  Colesule  more  prominent,  rising  from  a 
narrow  base,  oval  pynform,  the  upper  4th  part  5-plicate,  the  rest 
as  in  type." — ^Lindberg. 

Hab.  Glena,  Eillamey,  on  mosses,  and  on  the  stems  of  trees.  Totc 
Cascade,  among  Hypnum  eugyrium,  1873,  Dr.  Lindberg.  Dr. 
Lindbcrg  states  that  this  form  is  the  common  form  in  Scandi- 
navia, where  the  typical  form  is  much  rarer. 


Moore — On  Irish  Hepatica.  616 

9.  Zefeunea  paUm,  Lindberg  [Plate  43]. 

AutoBcious.  ''Shorter  and  twice  as  narrow  as  last  species,  pale, 
very  transparent,  shining  when  dry,  usually  more  branched 
and  interwoven,  remarkably  convex,  or  nearly  roundish.  Leaves 
more  or  less  crowded,  the  front  lobe  very  convex  when  dry, 
also  overlying,  rising  abruptly  at  a  nearly  right  angle  from  the 
basilar  lobe,  very  much  decurved  and  well  overlapping  the  stem — 
['  maxime  decurvus,  intus  caulem  valde  superans,' J  oblique,  broadly 
oval-elliptic,  or  very  blimtly  oval.  Collides  very  smooth,  scarcely 
or  not  at  all  chlorophyllif  erous,  much  thickened,  with  the  trigonal 
spaces  very  distinct.  Amphigastria  wide,  two  or  three  times  as 
short  as  the  hinder  lobe,  very  convex,  subrotund  and  cleft  in  the 
middle,  sinus  more  or  less  obtuse,  with  bluntish  segments,  every- 
where indented  with  projecting  cells.  Colesule  always  on  the 
lateral  branches,  slightly  projecting,  pyriform-clavate,  rounded 
b^low,  enfolding,  the  upper  4th  part  6-plicate,  with  prominent 
and  more  flattened  crests,  crenulate  at  apex." — ^Lindberg. 

Xcjeunea  patens,  Lindberg,  Acta  Soc.  Sci.  Fenn.  x.  p.  482  (read  1874, 
pub.  1875).  L.  serpyllifolia,  var.  y.  ovata,  Nees,  Nat.  Eur.  Leb. 
3,  p.  264  (1838). 

Hab.  Co.  Kerry,  **  Connor  Hill,  supraoppidulum  Dingle,  ad  Pleuroadam 
terra  tiuH^osa  humida  (coles)  et  ad  muscos  varies  in  rupibus 
sicciusculis;  Ventry  ad  Dingle  Bay;  Killamey,  0*  Sullivan's  Cas- 
cade ;  *  Supra  emortuum  Thamniumalopecurum,  Glena  etTorc  Cas- 
cade.' Killamey,  Tore  Cascade,  Dr.  Carrington  (1861).  Co.  Sligo, 
Benbulben  (Dr.  Moore)."     Glenad,  Co.  Leitrim,  1875. 

10.  Lejeunea  Moorei,  Lindberg  [Plate  44]. 

Autoecious.  **  Bather  rigid,  yellowish  or  very  green,  always  opaque 
and  not  pellucid,  almost  unbranched,  and  not  radiculose.  Leaves, 
front  lobe  imbricated,  hardly  or  very  little  overlapping  the 
stem — [*  intus  caulem  vix  vel  parum  superans'] — oblique,  ovate- 
elliptic,  roundly-obtuse,  quite  entire,  tibe  lower  margin  at  apex 
of  stem  recurved  when  dry,  basilar  sac  and  hinder  lobe  very 
small.  Cellules  covered  with  minute  papillae,  closely  packed  with 
chlorophyll,  slightly  thickened.  Amphigastria  imbricated, 
4-6  times  larger  than  the  hinder  lobe,  distinctly  cordate  at  the 
base,  not  decurrent,  ovately-oval,  very  entire,  cleft  in  the  centre 
by  a  narrow  and  acute  sinus,  the  segments  obtuse.  Perichsetia 
on  the  stem  itself,  and  on  innovations  from  the  apex  of  it." — 
Lindberg. 

[*' Jungermanniaflava,  Sw.  Prodr.  M.  Ind.-Occ.  p.  144,  et  Fl.  Lid.- 
Occ.  3,  p.  1869 ;  Schwaegr.  Hist.  Muse.  Hep.  Prodr.  p.  16,  n.  17 ; 
Weber  (F.),  Hist.  Muse.  Hep.  Prodr.  p.  29,  n.  15  ;  Sprengel  (L.), 
Syst.  Veg.,  16  ed.  4,  p.  1,  p.  223,  n.  74.  Lejeunea  flava,  Nees, 
Nat.  Eur.  Leb.  3,  p.  277,  in  obs.  2,  G.  L.  et  N.  Synop.  Hepat. 
p.  373,  n.  167;  Gottsche,  Mex.  Lev.  p.  219,  n.  46."]?  L.  Moorei, 
Lindb.  Act.  Soc.  Sci.  Fenn.  x.  p.  487. 


616  Proceedings  of  the  Royal  Irish  Academy. 

Hab.  ''Co.Eeiry:  Eillanie7,GleiiaetCromaglaun,lociB  umbrosiB  sihra- 
ram,  ad  truncos  arborum  vetustarum,  et  supra  Isopterjgiam 
elegans  in  fissuris  rupium." — Lindb.  Glen  at  the  Hnntmg  Tower, 
Cromaglaun,  1862;  0' Sullivan's  Cascade,  1875. 

11.  Zefeunea  Mackaii  (Rooker),  S^Tcn^L  Autoecious.  Stem  creeping. 
Leaves  distichous,  unequally  2-lobed,  the  upper  lobe  large  and 
round,  the  lower  small  and  involute.  Amphigaatria  obcordate, 
roundish,  wider  than  the  stem.  Golesule  compressed,  gibbous 
below,  mouth  contracted,  toothed.  Male  branches  proceeding 
from  side  of  stem,  not  in  axils  of  the  leaves,  but  directly  under 
the  leaf  next  above. 

Jungermannia  Mackaii,  Hook.  Brit.  Jung.  t.  53 ;  Engl.  Bot.  t.  2573; 
Lindb.  Hepat.  Europ.  p.  20;  Ekart,  Syn.  Jung.  p.  69,  t.  10,  ^^. 
72.  Phragmicoma  Mackaii,  Bumort.  Comm.  Bot.  p.  112;  SyU. 
Jung.  p.  35,  et  Hepat.  Europ.  p.  30 ;  Nccs,  Europ.  Leberm.,  3, 
p.  249;  G.  L.  et  N.  Synop.  Hep.  p.  293;  Rabenhor.  Hep. 
Europ.  exsic.  n.  81,  164,  206.  Marchesinia  Mackayi,  B.  Gr.  in 
Gray's  Arr.  Brit.  PI.  1,  p.  689.  Lejeunea  Mackaii,  Sprengcl,  Syst. 
Yegt.  ed.  16,  p.  1,  p.  233 ;  Lindberg,  Hepat.  Scand.  exsic,  fasc.  1. 

Hab.  Limestone  rocks  principally.  Frequemt  in  the  south  and  west 
of  Ireland,  rarer  in  the  north  and  east.  Very  large  and  fine  at 
Muckross,  Killamey,  and  by  the  side  of  a  lake  near  Letterfrack, 
Galway ;  Woodlands,  Dublin  ;  near  Cork,  frequent.  The  stems 
are  sometimes  quite  black,  when  creeping  over  the  nearly  per- 
pendicular faces  of  rocks. 

Badula,  Dumortier. 

Jungermannia,  Bupp.  Fl.  Jen.,  1  ed.  p.  345(1718);  Hooker,  Brit. 
Jung.  (1816);  Martinellia,  sect,  fl,  B.  Gray,  in  Gray's  Nat.  Arr. 
Brit.  PL  1,  p.  690  (1821).  Kadula,  Dumort.  Coram.  Bot.  p.  112 
(1823),  et  B^cueil,  1,  p.  14(1835);  Nees,  Nat.  Eur.  Leberm.  1, 
p.  96  (1833).  Jubula,  Corda,  in  Sturm,  Deutschl.  Fl.  2,  fasc.  26  et 
27,  p.  152  (1835). 

1.  Radtda  XalapenBiMy  N.  M.  (1836).  Dioecious.  Stems  procumbent, 
pinnately  branched.  Leaves  incubous,  orbicular,  obtuse,  entire, 
upper  lobe  large  and  broad,  undulate  and  somewhat  cordate  at 
base. 

Radula  Xalapensis,  N.  M.,  in  Ann.  Sc.  Nat.  2  series,  5,  p.  56  ;  Lindb. 
HepaticfiB  in  Hibemia  lectae  (1875).  Eadula  voluta,  Taylor,  in 
G.  L.  et  N.  Synop.  Hep.  p.  253  (1845) ;  Cooke's  Brit.  Hepat.  p. 
18,  fig.  136;  Dumort.  Hepat.  Europ.  p.  32. 

Hab.  Gn  wet  rocks  near  streams.  Dunkerron,  Dr.  Taylor.  Gn  boulders 
by  the  side  of  the  stream  below  Tore  Waterfall,  Killamey,  Pr. 
Carrington.  Rocks  below  the  Eagle's  Nest,  Cromaglaun,  George 
E.  Hunt.  Near  Dcrrycunighy  Cascade,  imd  at  Gortagre.  Dr.  Lind- 
berg states  that  he  can  find  no  great  distinction  between  the  Kil- 


Moore — On  Irish  Hepaticoe.  617 

lamey  plant  and  specimens  of  B.  Xalapensis,  which  he  possesses^ 
from  New  Granada,  collected  by  Lindig,  and  from  Tallulah 
Falls,  Georgia,  U.  S. 

2.  Radfda  aquiUgiay  Taylor.   Dioecious.    Stems  csespitose,  compressed. 

Leaves  distichous,  convex  on  the  upper  surface,  entire,  obovato- 
roundish,  unequally  2-lobed,  the  lower  lobe  closely  adpressed. 

Jungermannia  complanata,  p,  minor,  Hook.  Brit.  Junger.  t.  81 » 
fig.  17.  J.  aquilegia,  Taylor,  in  Trans.  Bot.  Soc.  of  Edinb.  2, 
p.  117.  Kadula  aquilegia,  Taylor,  in  G.  L.  et  N.  Synop.  Hepat. 
p.  260;  Cooke's  Brit.  Hepat.  p.  19,  figs.  139,  140;  Dumort. 
Hepat.  Europ.  p.  32. 

Hab.  On  rocks  and  trees.    Not  rare  in  the  Killamey  district. 

3.  Radulae<miplarMta{JATLn.\J^\imor^er,    Stems  creeping,  complanntc. 

Leaves  distichous,  imbricated,  unequally  2-lobed,  upper  lobe 
large,  and  nearly  round,  lower  lobe  much  smaller  and  ad- 
pressed.   Colesule  terminal,  oblong,  compressed,  truncate. 

Jungermannia  complanata,  Linn.  Sp.  PI. ;  Hook.  Brit.  Jung.  t.  81 ; 
Engl.  Bot.  t.  2499.  CandoUea  complanata,  Eaddi,  Jung.  Etr.  in 
Mem.  Modena,  xi.  Badula  complanata,  Dumort.  Comm.  Bot.  p. 
112;  Syll.  Jung.  p.  38  ;  Hepat.  Europ.  p.  32 ;  G.  L.  et  N.  Synop. 
Hep.  p.  267 ;  Rabenh.  Hep.  Europ.  exsic.  n.  17-361. 

Hab.  On  trees  and  rocks.  Very  common  in  every  part  of  Ireland. 
Varying  considerably  in  size  and  general  appearance  in  different 
localities,  and  under  peculiar  circumstances. 

PoEELLA,  Dillenius. 

Jungermannia,  Rupp.  El.  Jen.  1  ed.,  p.  345  (1718).  Porella,  Bill. 
Hist.  Muse.  p.  469,  tab.  68  (1741);  Linn,  in  Act.  Tips.  1741, 
p.  83  (1746) ;  Lindb.  in  Act.  Soc.  8c.  Fenn.  ix.,  329-345  (1869). 
Cavendishia, B.Gray,  in  Gray's  Nat.  Arr.  Brit. PI.  1.  p. 689  (1821). 
Madotheca,  Dumort.  Comm.  Bot.  p.  1 11  (1823).  Lejeunea,  Corda, 
in  Opiz,  Beitr.  1,  p.  662  (1829). 

Colesule  lateral,  compressed.  Capsule  nearly  sessile,  univalved,  4-cleft. 
Elaters  with  two  spires.  Antheridia  in  the  saccate  bases  of  the 
perigonial  leaves. 

1.  Porella  hevigata  (Rupp.,  Schrad.),  Lindberg.  Dioecious.  Stems  pros- 
trate, bipinnately  branched,  from  2-4  inches  long.  Leaves  inoubous, 
broadly  ovate,  dentate,  unequally  2-lobed,  the  smaller  lobe  closely 
pressed  against  the  base  of  the  larger  lobe.  Amphigastria  quad- 
rate, spinulose-dentate.   Colesule  dentate. 

Jungermannia  laevigata,  Schrader's  Sammlung,  n.  104;  Hook.  Brit. 
Jung.  tab.  35 ;  Lindenb,  Synop.  Hepat.  p.  18.  Madotheca  laevi- 
gata, Dumort.  Comm.  Bot.  p.  Ill ;  Syll.  Jung.  p.  34,  et  Hepat. 


618  Proceedings  of  the  Royal  Irish  Academy. 

Enrop.  p.  22  ;  G.  L.  et  N.  Synop.  Hepat.  p.  276.  Carendisliia 
laBvigata,  B.  Gray,  in  Gray's  Arr.  Brit.  PI.  1,  p.  690.  Porefla 
Isyigata,  Lindbcrg,  in  Act.  Soc.  Sc.  Fenn.  ix.,  p.  335. 

Ilab.  Near  Bantry,  Miss  Hutchins.  Near  Cork,  Isaac  Carroll. 
Lough  Bray,  Wicklow. 

Var.  fi.  inteyra  (Dill.),  Lindberg.  KiUamey,  Glena,  on  inundated 
stones  by  the  margin  of  the  lower  lake,  Dr.  Lindberg  (1873). 

2.  ParellaplatyphyUa{'L,),  Lindberg.  Stems  irregolarly  pinnate,  bran- 

ches nearly  of  equal  length,  sometimes  crowded  at  the  apex,  when- 
they  are  obtuse.  Leaves  incubous,  raised  at  their  upper  margin^ 
which  is  curved  and  undulated,  more  or  less  concave  at  the  base, 
and  decurved  at  the  apex,  mostly  entire  at  the  margin,  lobule  sub- 
oblique,  ovate-obtuse,  or  indistmctly  a  little  acute.  Amphigastria 
adpressed  to  the  stem,  oblong-ovate  or  ligulate,  slightly  recurved 
at  apex.     Anthcridia  in  the  axillae  of  the  perigonial  leaves. 

Jungermannia  platyphylla,  L.  8p.  PL  1  ed.,  p.  1134 ;  Wahlenb.  PI. 
Lapp.  p.  388,  n.  704 ;  Hook.  Brit.  Jung.  t.  40,  fig.  1  ;  Hartm. 
Skand.  PL,  1  ed.,  p.  435.  Cavendishia  platyphylla,  Gray's  Nat. 
Arr.  Brit.  PL  2,  p.  690 ;  Carruth.  in  Seemann's  Journal  Bot.  3,  p. 
301.  Madotheca platyphylla,  Dumort.  Comm.  Bot.  p.  Ill,  etSyU. 
Jung.  Eur.  p.  31 ;  G.  L.  et  N.  Synop.  Hep.  p.  278,  n.  30. 

Ifab.  On  rocks  and  stones  generally,  but  also  on  trees  and  moss-covered 
banks.    Frequent  in  many  parts  of  Ireland. 

3.  Forella  Thuja,  Dicks.     Stems  tufted,  branched  snbpinnately,  con- 

vex and  smooth  above.  Leaves  closely  imbricated,  lobed,  lower 
lobe  spreading,  entire  recurved,  anterior  ovate-obtuse,  margin 
rcflexed.  Amphigastria  oblong,  acute,  entire,  margin  reflexed, 
apex  recurved.  Involucral  bracts  for  the  most  part  ciliate-serratc. 
"Tufts  wide,  olive-green ;  the  older  parts  purplish  brown,  shining, 
the  shoots  acuminated." — Taylor. 
Lichcnastrum  Arboris  Vitae  facie,  foliis  rotundioribus.  Dill.  Hist.  Huso, 
p.  502,  tab.  72,  fig.  33.  Jungermannia  Thuja,  Dicks.  PL  Crypt. 
4,  p.  19  ;  Taylor,  in  Trans.  Bot.  Soc.  Edin.  2,  p.  116  ;  Hook.  Brit. 
Jung.  t.  40,  nn.  3-4.  Var.  fi,  major  et  var.  y.  Thuja.  Madotheca 
Thuja,  Dumort.  Comm.  Bot.  p.  Ill ;  Syll.  Jung.  p.  31,  et  Hepat. 
Europ.  p.  24. 

Hub.  On  rocks  and  stones.  Bantry,  Miss  Hutchins.  Near  Lough  Finnehy, 
Dunkerron,  Co.  Kerry,  Dr.  Taylor.  Loagh  Bray,  Co.  Wioklow; 
Brandon,  Co.  Kerry  (1864). 

4.  Forella  Cordttana^  Dumortier.     '*  Stems  bi-tripinnate.  Leaves  ovate 

entire,  attached  obliquely  to  stem,  auricles  oblique,  ovate, 
slightly  acute.  Amphigastna  subrotund,  entire.  Colesule  bilabiate, 
subcrenate. ' ' — Dum. 

*^  Jungermannia  Cordaeana,  Hiiben.  Hep.  Germ.  p.  291 ;  De  Not.  Prim. 
Hep.  Ital.  p.  10 ;  Mougeot  et  NesU.  Crypt.  Vog.  n.  1044.   Mado- 


Moore — On  Irish  Hepaticm.  619 

theca  CordsBanay  Dumort.  Bev.  Jung.  1,  p.  11.  Lejennea  Cor- 
deeana,  Nees  et  Mont.,  in  Ann.  Sc.  JJTat.  1836,  p.  7.  Madotheca 
porella,  Nees,  Eur.  Leberm.  3,  p.  201 ;  G.  L.  et  N.  Synop.  Hepat. 
p.  281." — Dumort.  Hepat.  Europ.  p.  25  (1874).  Cavendishia  rivu- 
laris,  Carruth.  in  Seem.  Joum.  Bot.  3,  p.  301.  Porella  dentata, 
Hartm.  Lindb.  in  Acta  Societatis  Scientiarum  EennicaB,  x. 

Hab.  On  wet  stones,  near  rivulets,  &c.  Near  Fermoy,  Co.  Cork,  T. 
Chandlee.  The  only  Irish  specimens  I  have  seen  are  those  col- 
lected  by  T.  Chandlee  in  the  locality  quoted.  They  were  named 
Madotheca  rivularis  when  sent  to  me,  and  Professor  Lindberg,  who 
examined  them  in  my  herbarium,  referred  them  with  certainty 
to  Madotheca  porella,  Nees. 

5.  Porella  pinnata,  L.  Stems  irregularly  pinnate,  or  subdichotomously 
branched.  Leaves  slightly  adpressed,  ovate-oblong,  plane  or  indis- 
tinctly decurved  at  the  apex,  margin  quite  entire,  lobule  minute, 
plane,  not  decurved,  spreading  from  the  stem.  Amphigastria  ad- 
pressed to  the  stem,  slightly  decurrent,  obtuse-rotundate. 

Porella  pinnata,  L.  Sp.  PL  1  ed.,  2,  p.  1106.  Jungermannia  porella, 
Dicks,  in  Trans.  L.  Soc.  3,  p.  239;  SchwsBgr.  in  Linncea,  13,  p.  1 14. 
Jung.  Cord®,  Hiiben.  Hep.  Germ.  p.  291.  Madotheca  porella,  Nees, 
Natur.  Eur.  Leberm.  3,  p.  201,  n.  6;  G.  L.  et  N.  Synop.  Hep. 
p.  281,  n.  35. 

Hab.  Near  Permoy,  Co.  Cork,  T.  Chandlee,  Esq.  Connor  Hill,  Co. 
Kerry,  Dr.  Lmdberg  (1873).  The  only  Irish  specimens  I  have 
seen  of  this  plant  are  those  from  T.  Chandlee,  which  were  sent 
tg  me  under  the  name  of  Madotheca  rivularis,  but  referred  un- 
hesitatingly to  Madotheca  porella,  Nees,  by  Dr.  Lindberg.  Not- 
withstanding the  labour  bestowed  on  the  genus  Porella  by  Dr. 
Lindberg  (Acta  Societatis  Scientiarum  Eennicae,  tom.  ix.,  1869), 
I  caimot  make  out  clearly  the  species  he  refers  P.  rivularis  to. 
He  quotes  some  of  the  same  authors,  namely,  Nees,  Hiibener, 
and  Carruthers'  works,  same  page  and  same  number  to  species,  as 
synonyms  of  his  Porella  dentata,  n.  5,  and  of  his  Porella  pinnata, 
n.  6.  Not  having  any  specimens  of  Taylor's  Jungermannia 
rivularis  (Trans.  Bot.  Soc.  Edin.  2,  p.  16),  I  am  unable  to  refer 
it  to  either  of  these.  Dr.  Carrington  notices  among  his  Irish 
Hepatic®  (Trans.  Bot.  Soc.  Edin.  7,  p.  455),  Madotheca  porella, 
Nees,  as  having  been  sent  to  Dr.  Gottsche  by  Dr.  Taylor  from 
south  of  Ireland ;  but  to  which  of  lindberg' s  species  is  it  refer- 
able? 

Sub-tribe  2.  Plettboziels. 

Pleteozia,  Dumortier. 

Jungermannia,  Weiss,  PI.  Crypt.  PL  Gott.  p.  123  (1770);   Sm.  Engl. 
Bot.  tab.  2500  (1813);  Hook.  Brit.  Jung.  (1816);  Hulen.  Hep. 


"620  Proceedings  of  the  Royal  Irish  Acadetny. 

Germ.  p.  275  (1834).    Pleurozia,  Diiin.  Recueil,  1,  p.  15  (1835). 

Physiotium,  Nees,  Nat.  Eur.  Leberm.  3,  pp.  6  et  75  (1838). 
Involucral  bracts  deeply  bilobed.  Colesule  cylindrical,  much  exserted, 

mouth  denticulate,  teeth  slightly  decurved  at  apex. 
Pleurozia    cochlear  if ormtSf   Dumortier.      Stems  long,   varying    from 

1  to  5-6  inches,  ascending.  Leaves  closely  imbricated,  unequally 

2-lobed,  upper  lobe  larger,  concave,  bifid,  and  serrated  at  the 

apex,  lower  lobe  pouch-like,  and  much  smaller,    colour  dark 

brown,  inclining  to  purple. 

Jungermannia  cochleariformis,  Weiss,  PI.  Crypt,  p.  123;  Hook.  Brit. 
Junger.  tab.  68.  Pleurozia  cochleariformis,  Dumort.  Rev.  Jung, 
p.  15;  Hepat.  Europ.  p.  52.  Physiotium  cochleariformis,  Nees, 
Europ.  Leberm.  3,  p.  79  ;  G.  L.  et  N,  Synop.  Hepat.  p.  235. 

Hab.  On  wet  bogs  and  moors.  This  is  probably  the  most  beautiful 
to  the  unaided  eye  among  all  the  British  or  Irish  species.  Where 
it  grows  freely  on  wide-spread  moors,  or  in  damp  situations  in  the 
more  mountamous  parts  of  the  counixy,  the  pretty  purplish  stems 
can  be  detected  ata  considerable  distance  i^m  the  spot  where 
they  grow.  It  ranges  from  the  northern  to  the  southern  counties, 
and  horn  the  eastern  to  the  western,  and  is  especially  abundant 
in  the  latter. 

h.  HoiCOOAlLS. 

"**  Stem  irregularly  branched,  with  branches  from  the  amphigastrial 
axil,  or  with  innovations  more  or  less  approximate  to  the  colesule, 
rarely  dichotomous,  pinnate  or  bipinnate.  Leaves  succubous  or 
incubous,  sometimes  opposite  or  connate,  rarely  conduplicate  and 
then  almost  always  the  front  lobe  is  smaller,  so  as  to  form  very 
variable,  round  or  reniform  to  sublinear,  quite  entire  to  broken 
up  in  filiform  segments.  Amphigastria  narrow,  more  or  less  ovate- 
lanceolate,  rarely  round,  quite  entire  to  broken  up  into  filiform 
segments,  sometimes  wanting.  Gamoecium  dioecious,  paroecious, 
more  rarely  autcecious.  PerichsBtium  proceeding  from  the  amphi- 
gastrial axilla  as  proper  branches,  either  apical  on  the  stem  and 
its  innovations,  or  in  many  frondose  forms  placed  on  the  inner 
face,  more  or  less  below  the  apex  of  the  stem,  sometimes  saccate 
and  dependent  from  the  stem.  Colesule  usually  large,  from  3-5 
plicate,  very  rarely  winged,  sometimes  complanate  or  compressed, 
occasionally  round  or  densely  plicate,  Very  rarely  winged,  with 
the  mouth  more  or  less  wide,  hardly  ever  beak-shaped.  Seta  long 
or  very  long,  sometimes  thickish.  Capsule  large,  globose-cylindric, 
of  thick  texture,  brown  and  not  pellucid,  as  if  formed  of  at  least 
two  strata,  valves  cleft  to  the  base,  patent  or  divaricate,  for  the 
most  part  shewing  spiral  fibres  intemdly.  Elaterstwo-,  rarely  one-, 
tri-,  or  quadri-spiral,  adhering  to  the  inner  face  of  capsule,  very 
rarely  to  apex  of  valves,  or  free.  Spores  minute  or  rather  large, 
sometimes  appendiculate  externally.    Androecia  proceeding  from 


Moore — On  Irish  Hepaticce.  621 

the  amphigastrial  axils  as  perichsBtia,  or  antheridia,  generally  two, 
rarely  more,  or  singly  in  the  axils  of  the  uppermost  leaves,  or 
in  the  frondose  forms,  fixed  over  the  anterior  face  of  the  stem  or 
immersed  in  it,  the  foot-stalk  straight,  hardly  ever  arcuately 
curved.  Faraphyses  sometimes  present,  usually  filiform." — Lind- 
bcrg. 

Subsection  f.  Opisthogailb. 
-"  Stem  irregularly  branched  by  bifurcation  at  the  apex,  or  with 
branches  from  the  amphigastrial  axils,  sometimes  pinnate  or  de- 
compound. Leaves  incubous  or  succubous,  very  rarely  condupli- 
cate,  entire  or  lobed.  Amphigastria  present,  at  least  in  the 
perichaetium  of  all,  very  like  the  leaves,  or  more  or  less  ovate,  undi- 
vided or  lobed.  Gamoscium  dioecious,  autoBcious,  rarely  parcecious. 
Female  branch  proceeding  from  the  amphigastrial  axillae,  almost 
always  short,  Colesule  triangular,  very  rarely  round,  compressed 
or  wanting.  Antheridia  on  a  proper  branch,  proceeding  from 
the  amphigastrial  axil,  hardly  ever  placed  in  the  foliar  aullaQ  of 
the  stem  itself.     Faraphyses  none." — ^Lindberg. 

Sub-tribe  3.  LspmoziEiE. 

Lepidozia  (Linn.),  Dumortier. 

Jungermannia,  L.  Sp.  Fl.  1,  ed.  2,  p.  1833  (1758);  Hook.  Brit.  Junger. 
(1816).  Blepharostoma,  Dumort.  Syll.  Jung.  Eur.  p.  65  (1831). 
Fleuroschisma,  sect.  2,  Lepidozia,  Dumort.  Syll.  Jung.  Eur. 
Mastigophora,  Nees,  Nat.  Eur.  Leber.  1,  p.  95  (1833).  Lepidozia, 
Dumort.  Recueil,  1,  p.  19  (1835) ;  G.  L.  et  K,  Synop.  Hepat.  p. 
200  (1845). 

Involucre  polyphyllous,  imbricated  on  every  side,  scale-Hke  and 
denticidate  at  the  apex.  Colesule  cylindrical,  sulcate,  denticulate 
at  the  mouth,  peduncle  not  articulate. 

1.  i>pirfa2uirtfj?^fl»<  (Linn.),  Dumortier.  Stems  casspitosc,  creeping,  and 

irregularly  branched,  varying  from  one  to  two  inches  in  length, 
flagiUiferous.  Leaves  incubous,  decurved,  sub-quadrate,  acutely 
3-4  toothed.  Amphigastria  wider  than  the  stem,  quadrate, 
quadridentate.  Colesule  dorsal. 
Jungermannia  reptans,  Linn.  Sp.  Fl.,  1599 ;  Hook.  Brit.  Jung.,  t.  75; 
Engl.  Bot.  t.  608 ;  Lindenb.  Synop.  Hepat.,  p.  44 ;  De  Notar. 
Frim.  Hepat.  Ital.  p.  21.  Lepidozia  reptans,  Dumort.  Rev. 
Jung.  p.  19,  et  Hepat.  Europ.  p.  109;  G.  L.  et  N,  Synop. 
Hepat.  p.  205 ;  Eabenhor.  Hepat.  Europ.  exsic,  282-479.  Mas- 
tigophora reptans,  Nees,  Leber.  Europ.  3,  p.  31. 

Hab.  Woods  and  bushy  banks.  This  beautiful  plant  occurs  in  more 
or  less  abundance  in  every  county  in  Ireland. 

2.  Lepidozia  eupremna  (Sw.),  Dum.  Stems  subcrect,  densely  packed  to- 

gether and  closely  pinnate.  Leaves  subcordate,  oblique,  quadrifid 


622  Proceedings  of  the  Royal  Irish  Academy. 

at  the  points,  the  lower  tooth  incurved.  Amphigastria  quadrifid^ 
broader  than  the  stem. 

Jungermannia  reptans,  p,  pinnata.  Hook.  Brit.  Jung.,  t.  75.  Lcpi- 
dozia  pinnata,  Dumort.  Key.  Jung.,  p.  19.  Lepidozia  tumidula, 
Taylor,  in  G.  L.  et  N.  Synop.  Hepat.,  p.  206.  Lepidozia  cu- 
pressina,  Lindberg,  Carring.  Irish  Hepat.,  Trans.  Bot.  Soc.  £din. 
7,  p.  453,  tab.  2,  fig.  xi. 

Hab.  On  the  ledges  of  damp  rocks  and  on  banks.  Very  abundant  in  the 
Killamey  woods.  In  the  larger  size  and  general  appearance  of 
this  plant,  it  shows  a  difference  compared  with  the  former  species. 
It  varies,  however,  so  much  in  these  respects,  according  to  the 
habitats  where  it  grows,  that  it  is  not  easy  to  separate  them  dis- 
tinctly. The  form  and  size  of  the  areolae  are,  however,  different, 
as  pointed  out  by  Dr.  Carrington,  and  the  incurved  central  tooth 
of  the  leaves  is  constant  in  the  latter.  Dr.  Lindberg,  who  has  of 
late  years  studied  the  Hepaticee  so  carefully,  considers  the  Irish 
plant  to  be  specifically  identical  with  the  American  L.  cupressina^ 
in  which  respect  Dr.  Carrington  agrees. 

Bazzania,  Bennett,  Gray. 

Jungermannia,  L.  Fl.  Suec.  1  ed.,  p.  335,  excl.  Synon.  Micheli  (1753) ; 
Hook,  emend.  Brit.  Jung.  (1816).  Bazzania,  B.  Gr.  in  Gray's 
Nat.  Arr.  Brit.  PI.  1,  p.  704  (1821).  Pleuroschisma,  sect.  3, 
Pleuroschismotypus,  Dum.  Syll.  Jung.  Europ.  p.  70  (1831). 
Herpetium,  Nees,  Nat.  Eur.  Leber.  1,  p.  96  (1833).  Mastigo- 
bryum,  G.  L.  et  N.  Synop.  Hepat.,  p.  214  (1845). 

Involucre  polyphyllous,  bracts  scale-like,  imbricated  on  each  side. 
Colesule  dorsal,  subacuminate,  compressed  at  the  mouth,  pe- 
duncles inarticulated. 

1.  Bazzania  trilohata  (Mich.,  L.),  B.  Gr.  Stems  creeping,  branched^ 
with  flagellaB.  Leaves  incubous,  ovate,  concave,  narrowed  towards 
the  points,  which  are  tridentate.  Amphigastria  broad  and  quad- 
rate, as  wide  or  wider  than  the  stem.  Colesule  dorsal,  slit  on  one 
side,  mouth  entire. 

Jungermannia  trilohata,  Linn.  Sp.  PI.  1599 ;  Hook.  Brit.  Jung, 
t.  76 ;  De  Notar.  Hepat.  Ital.  p.  20 ;  Taylor,  in  Fl.  Hib.  p.  65. 
Jungermannia  radicans,  Hoff.  Germ.  2,  p.  87 ;  Engl.  Bot.  t.  2232. 
Pleuroschisma  trilohata,  Dumort.  Syll.  Jung.  Eur.  p.  70,  n,  96, 
et  Hepat.  Europ.  p.  103.  Mastigobryum  trilobatum,  G.  L.  et  N* 
Synop.  Hepat.  p.  230. 

Hab.  Mountain  woods,  and  rocky  places,  in  many  parts  of  the  country. 
Sleemish  Mountdn,  Co.  Antrim;  Dart  Mountain,  Co.  Derry. 
More  abundant  in  the  south,  especially  in  the  Killamey  woods. 
About  Kylemore,  Co.  Galway. 


Moore — On  Irish  Hepaticc^.  623 

2.  Basaania  triangularis^  Schleich.     StepM  small,  decumbent,  fragile. 

Leaves  incubous,  ovoid,  convex,  tri-crenate  at  the  narrow  apex. 

Amphigastna  roundish-ovate,  broader  than  the  stem,  and  notched 

at  the  apex. 
Jungermannia  triangularis,  Schleich.  PI.  Crypt.  Helv.  2,  n.  61.     J. 

tricrenata,  Wahlenb.  Fl.  Crypt,  p.  364;  Lmdenb.  Synop.  Hepat.  p. 

43 ;  Ekart,  Syn.  Jung.  p.  49,  t.  12,  fig.  99 ;  De  Notar.  Prim. 

Hepat.  Ital.  p.  20.  J.  deflexa.  Mart.  PI.  Crypt.  Erlang.  p.  135,  t.  3, 

fig.  8.  Bazzania  trilobata,  var.  p.  minor,  B.  Gr.  in  Gray's  Arrang. 

Br.  PL  1,  p.  704.    Pleuroschisma  deflexum,  Dumort.  Syll.  Jung. 

p.  71,  et  Hepat.  Europ.  p.  105. 
Hab.  Bushy  places  and  woods.    Frequent  about  Tore  Mountain, 

Cromagloun,  and  other  places  near  Killamey,  Dr.  Carrington. 

0' Sullivan's  cascade,  and  Brandon  Mountain,  Kerry.     Glenbower 

wood,  near  Fermoy,  Isaac  Carroll,  Esq.     Glenarrif,  Co.  Leitrim. 

On  the  high  limestone  range  of  Bcnbulben,  Co.  Sligo,  not  un- 

frequent. 

OnoNTOscHisMA,  Dumorticr. 

Jungermannia,  Dicks.  Fasc.  PL  Crypt.  Brit.  1,  p.  6,  tab.  1,  fig.  10 
(1785);  Hooker,  Brit.  Jung.  (1816).  Martinellia,  sect,  i,  B.  Gr.  in 
Gray's  Arr.  Brit.  PL  1,  p.  693  (1821).  Odontoschisma,  Dum.  Re- 
cueil,  1,  p.  19,  n.  25  (1835).  Sphagnocetis,  Nees,  in  G.  L.  et  N. 
Synop.  Hepat.  p.  148  (1845).  Gymnanthe,  Mitten,  in  Jour.  Linn. 
Soc.  7,  p.  166  (1863). 

Involucre  polyphyllous,  bracts  in  several  rows,  imbricated,  bilobed. 
Colesule  cylindrical,  cleft  at  one  side,  denticulate  at  the  mouth, 
originating  from  the  under  side  of  the  branch,  and  shortly  pedun- 
culate. 

1.  Odontoschisma  gphagni  (Dicks,),  J)umoTtier.  Dioecious.  Stem  ascend- 

ing singly  or  in  small  patches  among  mosses.  Leaves  close,  succu- 
1)ous,  orbicular,  secund.  Amphigastria  small,  lanceolate,  and  only 
on  the  young  shoots.  Colesule  terminal,  upon  a  short  proper 
branch,  originating  from  the  ventral  side  of  the  stem,  ol^ong, 
wider  in  the  middle,  the  mouth  denticulate. 
Jungermannia  sphagni,  Dicks.  Fasc.  PL  Crypt.  Brit.  1,  p.  6;  Engl. 
Bot.  t.  2470 ;  Hook.  Brit.  Jung.  t.  33 ;  Lindenb.  Synop.  Hep.  p. 
28;  Taylor,  in  Fl.  Hib.  2,  p.  58.  Odontoschisma  sphagni, 
Dumort.  Rev.  Jung.  p.  19,  et  Hepat.  Europ.  p.  108.  Sphagno- 
cetis communis,  Nees,  in  G.  L.  et  'N.  Synop.  Hepat.  p.  148; 
Rabenhor.  Hep.  Europ.  exsic.  n.  300-566,  440. 

Hab.  In  bogs  among  Sphagnum.  Frequent  in  most  parts  of  Ireland, 
but  more  abundant  in  the  south  than  elsewhere. 

2.  Odontoschisma  denudatum  (Nees),  Dumort.    Dioecious.    Stem  pro- 

cumbent, branched,  branches  with  flagellse,  ascending  and  leafless 
near  the  points,  tipped  with  gonidiferous  gemmaD.   Leaves  small 

B.  I.  A.  FBOC— VOL.  U.,  8XB.  II.,  BCI£KCB.  8  0 


624  Proceedings  of  the  Boydl  Irish  Academy. 

at  the  base,  or  none,  increasing  in  size  towards  the  middle  of  the 
stem,  and  decreasing  from  the  middle  to  the  apex,  succubous, 
second,  roundish-ovate^  with  the  points  sometimes  slightly  emar- 
ginate.  Amphigastria  larger  and  more  readily  observed  than 
they  are  in  the  former  species,  confined  to  the  younger  branches. 
Colesule  cylindrical,  fringed  at  the  mouth. 

Jungermannia  denudata,  Nees,  in  Mart.  El.  Crypt.  Erlang.  p.  14; 
Lindenb.  Synop.  Hepat.  Europ.  p.  71,  n.  69;  Hartm.  Skand.  Fl. 
3  ed.  p.  319.  Odontoschisma  denudatum,  Dumort.  Becueil,  1, 
p.  19  ;  et  Hepat.  Europ.  p.  108.  Jungermannia  sphagni,  Hook. 
Brit.  Jung,  suppl.  t.  3 ;  Ekart,  Synop.  Jung.  Germ.  t.  6,  f .  48. 
Spheignoecetis  communis,  p.  macrior,  Nees,  in  G.  L.  et  K.  Synop. 
Hep.  p.  149. 

Hab.  On  rotten  trunks  of  trees,  and  in  wet  places  in  shady  woods. 
On  the  side  of  Corslieve  Mountain,  near  Bangore,  Go.  Mayo  (1859). 

Cephalozia,  Bumortier. 

Jungermannia,  Mich.  Nov.  PI.  Gen.  p.  9,  no.  5,  tab.  6,  fig.  17  (1729); 
Hook.  Brit.  Jung.  (1816).  Cephalozia,  Dumort.  Recueil,  1,  p.  18, 
n.  21  (1835).  Zoopsis,  Hooker,  in  Tayl.  Crypt.  Fl.  Antarct. 
p.  55  (1845).  Trigonanthus,  Spruce,  in  Trans.  Bot.  Soc.  Edinb.  3, 
p.  207  (1849). 

**  Involucre  polyphyllous,  gemmiform,  bracteolee  deeply  lacerated, 
imbricated  in  several  rows  all  round  the  stem  and  base  of  the  cole- 
sule, exterior,  stipuliform.  Colesule  sessile,  erect,  round,  inflated, 
contracted  at  apex,  mouth  toothed.  Capsule  4-valved,  of  thick 
consistence,  naked.  Elaters  geminate,  naked,  deciduous." — 
Dumortier. 

{a).  Amphigastria  present, 

1.  Cephalozia  Francisciy  Hook.  (Dumort.)    Stems  nearly  erect,  slightly 

branching.  Leaves  incumbent,  ovate,  acutely  emarginate.  Amphi- 
gastria minute,  ovate,  bifid.  Colesule  terminal,  on  short  lateral 
branches. 

Jungermannia  Erancisci,  Hook.  Brit.  Jung.  t.  49 ;  Engl.  Bot.  t.  2369 ; 
Taylor,  in  Fl.  Hib.  2,  p.  64 ;  Nees,  Europ.  Leberm.  2,  p.  220 ; 
G.  L.  et  N.  Synop.  Hepat.  p.  133;  Rabenhor.  Hepat.  Europ. 
exsic.  n.  503.  Cephalozia  Erancisci,  Dumort.  Bev.  Jung.  p.  18 ; 
Hepat.  Europ.  p.  88 ;  Cogn.  Hepat.  Belg.  p.  35. 

Hab.  Shady  banks  and  rocks.  Near  Bantry,  Miss  Hutchins.  Very 
rare  in  Ireland. 

2.  Cephalozia  divaricatay^wi^h^J^umoTt,)   Autoecious.  Stems  creeping. 

Leaves  roundish  and  semi-bifid,  segments  divergent.  Amphi- 
gastria subulate,  bifid.  Colesule  terminal,  cylindncal,  truncate, 
toothed  at  the  mouth. 


Moore — On  Irish  HepaticcB.  625 

Jangermannia  divaricata,  Sm.  Engl.  Bot.  t.  719;  Spruce,  in  Trans. 
Bot.  Soc.  Edinb.  3.  p.  207.  J.  Starkii,  G.  L.  et  N.  Synop.  Hepat. 
p.  134.  Cephalozia  Starki,.  Dumort.  in  Cogn.  Hep.  Belg.  p.  35. 
Trigonanthus  divaricatus,  Hartm.  Skand.  Fl.  10  ed.,  p.  143. 

Hab.  On  heathy  banks  in  hilly  places.  Sleemish  Mountain,  and  Fair 
Head,  Co.  Antrim;  Brandon,  Kerry.  Cromagloun,  Kerry,  Dr. 
Carrington.     Near  Glenarm,  Dr.  Dickie. 

•3.  Cephalozia  elaehtsta,  Jack.  Paroecious.  Stems  very  small  and  some- 
what rigid.  Leaves  variable,  inclined  to  quadrate,  deeply  bifid 
but  sometimes  entire,  segments  nearly  linear,  bearing  occa- 
sionally a  well-developed  tooth  or  two,  but  more  frequently  with- 
out teeth.  Amphigastria  generally  present,  especially  among 
the  perichsBtial  leaves.  Involucral  bracts  much  larger  than  the 
cauline  leaves,  irregularly  lobed,  lacerated  at  the  margin,  and  im- 
bricated on  every  side.  Perigonial  leaves  strongly  toothed  at 
their  margins,  and  terminating  in  longish  incurved  points. 
Gamcecium  and  Androecium  on  same  branch,  but  separate  (paroe- 
cious). Colesule  roundish  or  inclined  to  triangular,  but  rather 
variable  in  form,  contracted  and  ciliated  at  the  mouth.  Anthe- 
ridia  with  short  stalks  in  the  axils  of  the  perigonial  leaves, 
singly. 

Jungermannia  elachista.  Jack,  in  Gottsche  et  Eabenhor.  Hepat.  Europ. 
exsic.  no.  674,  with  excellent  figure  and  full  description  by  Dr. 
Gottsche. 

Hab.  On  moist  bare  banks  at  Brandon,  Co.  Kerry  (1864).  At 
Lough  Bray,  Co.  Wicklow,  Dr.  Lindberg,  June,  1873. 

{h),  Amphigastria  wanting. 

4.  C^halo%ia  hyasaeea  (Roth),  Dumort.  Stems  procumbent,  branch- 
ing. Leaves  remote,  incumbent,  subquadrate,  bifid,  segments 
acute.  Colesule  terminal,  cylindrical,  plicate,  toothed  at  the 
mouth. 

Jungermannia  byssacea,  Eoth,  Fl.  Germ.  3,  p.  387  ;  Hook.  Brit.  Jung, 
t.  12;  Taylor,  in  Fl.  Hib.  2,  p.  60 ;  Fl.  Dan.  t.  1717,  f .  1  ;  De 
Notaris,  Prim.  Hep.  Ital.  p.  29.  Cephalozia  byssacea,  Dumort. 
Rev.  Jung.  p.  18;  Hepat.  Europ.  p.  90;  Cogn.  Hep.  Belg. 
p.  33. 

Hab.  "  On  paths  in  woods,  and  on  bare  crags  ;  common." — Dr. 
Taylor. 

I  have  enumerated  this  so-named  plant  out  of  deference  to  some  of  our 
greatest  hepaticists,  although  I  am  by  no  means  clear  about  the 
characters  which  distinguish  it  from  C.  divaricata.  Dumortier 
places  the  two  in  different  sections  of  Cephalozia,  and  refers  C. 
divaricata  to  the  figure  in  English  Botany  quoted,  and  C.  byssacea 
to  the  figure  in  Hooker's  British  JungermanniaB.   I  had  collected  in 

3o2 


626  Proceedings  of  the  Royal  Irish  Academy. 

varioxis  parts  of  Ireland  what  I  considered  to  be  the  latter,  but 
when  my  specimens  were  examined  by  Drs.  Carrington  and 
Lindberg,  they  referred  all  of  them  to  C.  divaricata,  Engl.  Bot. 
Dr.  Taylor  states  it  to  be  common  in  Ireland.  The  presence  or 
absence  of  amphigastria  do  not  appear  to  be  decisive  distinguishing 
characters,  as  Mr.  Spruce  states  in  his  remarks  on  Jung,  divari- 
cata  (in  Hepat.  Pyrenees,  Trans.  Bot.  Soc.  Edinb.,  3,  p.  207), 
that  some  of  his  specimens  have  stipules,  and  some  are  altogether 
without  them. 

5.  Cephalgia  hicuspidata{JAxm.\Jhrniort,  Autoecious.  Stem  creeping, 

branched.  Leaves  incumbent,  lax,  subquadrate,  bifid,  segments 
long,  acute.  Involucral  bracts  2-3  cleft,  imbricated.  Colesule 
radical  and  terminal  on  lateral  branches,  plicate  and  toothed  at 
the  mouth. 

Jungermannia  bicuspidata,  Linn.  Sp.  PI.  158  ;  Hook.  Brit.  Jung.  1. 11 ; 

Engl.  Bot.  2239 ;  Nees,   Europ.  Leber.  2,  p.  351 ;  De  iNotaris, 

Prim.  Hepat.  Ital.  p.  27 ;  G.  L.  et  N.  Synop.  Hepat.,  p.  138. 

Cephalozia  bicuspidata,  Dumort.  Rev.  Jung.,  p.  18  ;  Hep.  Eur.  p. 

91.    Trigonanthus  bicuspidatus,  Hartm.  Skand.  PL  10  ed.,  p.  143. 
Far.  a.  major f  Nephin  Mountain,  Mayo. 
Var,  p,  riyidtda,  Cromagloun,  Kerry,  Dr,  Carrington. 
Hab.  On  heaths  and  banks.     A  very  common  species  in  many  parts  of 

Ireland. 

6.  Cephalgia  ewrvifolia  (Dickson),  Dumort.     Autoecious.     Stems  pro- 

cumbent. Leaves  semi-verticillate,  concave,  deeply  bifid,  segments 
long,  setaceous  at  the  points,  and  much  incurved.  Colesule  on 
lateral  branches,  oblong,  subplicate,  contracted,  and  toothed. 

Jungermannia  curvifolia,  Dicks.  PL  Crypt.  2,  p.  15,  t.  3,  f .  7  ;  Hook. 
Brit.  Jung.  t.  16 ;  Engl.  Bot.  t.  1304  (not  good)  ;  Caning,  in 
Trans.  Bot.  Soc.  Edinb.,  vol.  7,  pi.  11,  fig.  4;  Lindenb.  Synop* 
Hep.  p.  91 ;  Taylor,  in  PL  Hib.  2,  p.  60 ;  G.  L.  et  K  Synop. 
Hepat.  p.  142 ;  Rabenhor.  Hep.  Europ.  exsic.  n.  72,  217,  &c. 
Cephalozia  curvifolia,  Dumort.  Hepat.  Europ.,  p.  93. 

Hab.  On  decaying  trunks  of  trees ;  also  on  moss-covered  banks,  among 
mosses.  Prequent  about  Killamey ;  Connor  Hill,  Kerry ;  Kyle- 
more,  Galway;  Glenade,  Leitrim. 

Tar.  p,  Baureri  =  Cephalozia  Baueri,  Lindberg, 

Hab.  Cromagloun,  and  elsewhere  in  the  Killamey  district. 

7.  Cephalozia  connivem,  Dicks.     Stem  procumbent,  slightly  branched. 

Leaves  accumbent,  suborbicular,  concave,  deeply  bifid,  segments 
incurved,  connivent.  Colesule  terminal,  on  lateral  branches, 
ovate,  contracted  and  ciliated  at  the  apex. 
Jungermannia  connivens,  Dicks.  PL  Crypt.,  fasc.  4,  p.  19,  tab.  2,  fig.  15; 
Hook.  Brit.  Jung.  tab.  15 ;  Engl.  Bot.,  t.  2436 ;  Tayl.  in  PL  Hib., 
p.  2,  p.  60 ;  DeNot.,  Prim.  Hep.  Ital.,  p.  27.  Blepharostoma  con- 


Moore — On  Lnsh  Hepaticm.  627 

mvens,  Dumort.  Rev.  Jung.,  p.  18;  Hepat.  Europ.,  p.  96  (1874); 
Cogn.  Hepat.  Belg.,  p.  36. 

Hab.  Wet  banks  among  mosses,  and  bogs  among  Sphagnum.  Bather 
common  in  many  parts  of  Ireland,  but  more  abundant  in  the 
southern  and  western  counties. 

Var,  a.  emferta  minor.     On  rotten  wood  frequent,  Carrington. 

Var.  p,  sphagnorumy  Hook.  Brit.  Jung.,  t.  15,  3.  More  or  less  fre- 
quent among  Sphagnum  in  many  of  the  bogs  through  Ireland, 
but  never  in  much  quantity  together. 

^.  Cephalozia  catmulata  (Hiibencr),  Lindb.  Stem  ascending,  flexuose, 
rigid.  Leaves  ovate,  concave,  acutely  bifid,  adpressed.  Involucral 
bracts  bi-tri-fid.  Colesule  cylindrically  trigonous,  minutely 
toothed  at  the  apex. 

Jungermannia  catenulata,  Hubener,  Hepat.  Grerm.,  p.  169 ;  Nees,  Eur. 
Leber.  11,  p.  248;  G.  L.  et  N.  Synop.  Hepat,  p.  138  ;  Raben- 
hor.  Hep.  Eur.  exsic,  p.  435,  cum  ie.  tfungermannia  reclusa,  Tay- 
lor, in  Trans.  Bot.  Soc.  Edinb.  U,  p.  44 ;  et  Lend.  Journal  Bot.  5, 
p.  278 ;  Spruce,  Muse,  et  Hepat.  Pyren.  in  Trans.  Bot.  Soc.  Edinb. 
III.,  p.  208;  Bot.  Zeit.  1,  p.  694.  J.  catenulata.  Caning,  in 
Trans.  Bot.  Soc.  Edinb.  7,  p.  449.  t.  11,  fig.  2.  Cephalozia  cate- 
nulata, Lindb.  in  Jour.  Linn.  Soc.  vol.  xiu.  p.  191. 

Hab.  On  shady  damp  banks,  and  in  woods.  Yery  common  in  the  Kil- 
lamey  and  Cromagloun  woods;  also  about  Brandon  Mountain 
as  well  as  elsewhere  in  Co.  Kerry ;  about  Kylemore,  Co.  Galway ; 
Lackan  bay,  Co.  Mayo  ;  Gleniff,  Co.  Leitrim ;  Lough  Bray,  Co. 
Wicklow. 

This  pretty  little  plant  is  rather  puzzling  at  times  to  distinguish  from 
certain  states  of  other  species  of  tibe  genus.  It  bears  a  greater 
resemblance  to  young  forms  of  C.  connivens  than  to  any  other. 
Dr.  Carrington,  who  has  paid  great  attention  to  it,  and  figured  it 
(Trans.  Bot.  Soc.  'Edinb,  I.e.),  considers  Taylor's  J.  reclusa  identical 
with  Hubener's  C.  catenulata,  as  also  does  Dr.  Lindberg,  who  has 
had  such  excellent  opportunities  for  comparing  the  Irish  plant 
with  foreign  specimens  of  C.  catenulata.  Dumortier,  however, 
holds  that  they  are  distinct  species,  and  describes  them  as  such 
(Hepat.  Europ.,  p.  92  (1874)).  Dr.  Spruce,  another  excellent 
observer,  agrees  with  Dumortier,  and  describes  J.  reclusa,  Taylor 
(see  his  Muse,  et  Hepat.  Pyren.,  in  Trans.  Bot.  Soc.  Edinb.,  m. 
p.  208,  as  a  distinct  species). 

"9.   Cephalozia  Turneri  (Hook.),   Lindb.     Stems  creeping,  branched. 

Leaves  incumbent,  acutely  bipartite,  segments  conduplicate,  spi- 

nulose-dentato.    Colesule  terminal,  contracted  and  slightly  dentate 

at  the  mouth. 
Jungermannia  Turneri,  Hook.  Brit.  Jung.  t.  22  ;  Engl.  Bot.,  t.  2310 ; 

Lindenb.  Synop.  Hepat.,  p.  92;  Nees,  Europ.  Leber.,  1,  p.  265; 


628  Proceedings  of  the  Royal  Irish  Academy. 

G.  L.  et  N.  Synop.  Hepat.,  p.  143 ;  Taylor,  in  Fl.  Hib.,  p.  2,  p.  60. 
Anthelia  Tumeri,  Dumort.  Rev.  Jung.,  p.  18  ;  et  Hepat.  Europ.^ 
p.  99  (1874).  Cephalozia  Tumeri,  lindberg,  in  Journal  of  Linn. 
Soc,  vol.  xni.,  p.  191. 

Hab.  Shady  damp  banks.  By  the  side  of  a  mountain  rivulet  near 
Bantry,  Co.  Cork,  Miss  Hutchins,  bearing  female  fruit  in  March, 
( 181 1 )  [?]  On  a  wet  sandy  bank  at  Cromagloun,  Co.  Kerry,  bear- 
ing  autoDcious  colesules,  23rd  July,  1873,  Dr.'Lindberg.  I  am 
not  aware  that  this  exceedingly  rare  plant  has  been  collected 
elsewhere  in  the  British  Isles,  or  by  any  other  person  than  those- 
named. 

LoPHOCOLBA,  Dumorticr. 

Jungermannia,  Mich.  Nov.  PL  Gen.  p.  8,  tab.  51,  fig.  12  (1729);  L. 
Sp.  PL  1  ed.,  2,  p.  1132  (1753);  Hooker,  Brit.  Jung.  (1816). 
Lophocolea,  Dumort.  Recueil,  1,  p.  17  (1835);  Nees,  Nat.  Eur. 
Leber.,  2,  p.  321  (1836). 

Involucre  oligophyllous,  dentate  or  cleft.  Colesule  sessile,  cylindrical,, 
mouth  3-cleft  and  cristated. 

1,  lA)phocolmhidmtatayluum,(J)vimoTt,)    Autoecious.     Stem  procum- 

bent, branched.  Leaves  accumbent,  broadly  ovate,  slightly  decur- 
rent  and  emarginate,  acutely  bidentate.  Amphigastria  bi-tri-fid, 
laciniated.  Colesule  oblong-triangular,  mouth  laciniated.  An^ 
theridia  in  the  axillse  of  the  perigonial  bracts,  two  or  three- 
together. 

Jungermannia  bidentata,  Sm.  Engl.  Bot.  t.  606;  Hook.  Brit.  Jung, 
t.  30 ;  Taylor,  in  FL  Hib.  2,  p.  64.  Lophocolea  bidentata^ 
Dumort.  Rev.  Jung.,  p.  17 ;  et  Hepat.  Europ.,  p.  83.  Lophocolea 
Hookeriana,  Nees,  G.  L.  et  N.  Synop.  Hepat.,  p.  161 ;  Cogn.  Hepat. 
Belg.,  p.  33 ;  G.  L.  et  N.  in  Synop.  Hepat.  Europ.  The  latter 
refer  the  J.  bidentata,  Linn.,  to  another  species,  and  state  that 
the  var.  y.  of  it  is  found  near  Dunkerron,  Kerry,  by  Dr.  Taylor. 
We  suppose  this  is  the  form  he  mentions  in  Fl.  Hib.  2,  p.  64, 
which  grows  necu:  Blackwater  bridge,  **  with  the  calyces  acutely 
triangular,  the  angle  corresponding  to  the  inferior  side  of  the- 
stem  serrate." 

FJir.  p,  cuspidata  (Gottschc).  On  dead  trees,  Killamey,  Dr.  Caning- 
ton. 

Var,  y.  graciUy  Carrington,  Irish  Hepat.,  Trans.  Bot.  Soc.  Edinb.,, 
vol.  7,  p.  452,  pi.  11,  fig.  6.    Woods,  KiUam^y. 

2.  Lophocolea  heterophylla   (Schrad.),    Dumort.       Stems   ascending^ 

branched.  Leaves  roundish,  quadrangular,  obtusely  emarginate. 
Involucral  bracts  lobed  and  dentate.  Amphigastria  2-3  fid,  and 
dentate.     Colesule  terminal,  mouth  crested. 


Moore — On  Itnsh  Hepaticce.  629 

Jungermaniiia  heterophylla,  Schrad.,  Journal  Bot.  1,  p.  66;  Hook. 
Brit.  Jung.  t.  31 ;  De  ISTotaris,  Prim.  Hepat.  Ital.  p.  25.  Lopho- 
colea  heterophylla,  Dumort.  Rev.  Jung.,  p.  17,  et  Hepat.  Europ., 
p.  86;  Nees,  Europ.  Leber.  2,  p.  338;  G.  L.  et  N.,  Synop. 
Hepat.,  p.  164. 

Hab.  In  woods  and  on  banks.  Tore  Mountain,  Killamey,  Dr.  Car- 
rington.  Near  Cong,  Co>  Gal  way.  Near  Fermoy,  Isaac  Carroll, 
Esq.  Dr.  Taylor  unites  this  species  with  the  former  in  Flora 
Hibemica,  and  states  that  he  finds  in  Kerry  varieties  so  inter- 
mediate that  with  the  utmost  care  he  found  it  impossible  to 
refer  them  definitely  to  one  more  than  the  other.  (Fl.  Hib. 
p.  2,  p.  65  (1836)). 

3.  Lophocolea  spicatay  Taylor.  Autoecious.  Stem  creeping,  branched. 
Leaves  oval-horizontal,  2-,  3-,  or  more  toothed  at  the  apex. 
Amphigastria  small,  cleft  nearly  to  the  base.  Colesule  terminal, 
prismatical,  and  lacerated  at  the  mouth,  lobes  toothed. 

Lophocolea  spicata,  Taylor,  in  G.  L.  et  N.  Synop.  Hepat.,  p.  167 ; 
Cooke,  Brit.  Hepat.,  p.  15,  n.  75,  fig.  113;  Dumort.  Hepat. 
Europ.,  p.  86. 

Hab.  On  shady  damp  rocks  among  mosses.  Dunkerron,  Kerry,  Dr. 
Taylor.  Bantry,  Miss  Hutchins.  Tore  Cascade,  Killamey,  Dr. 
Carrington.  Glensiskin,  Cork,  T.  Chandlee,  Esq.  By  the  side  of 
the  Upper  Lake,  Killamey,  in  fruit,  June,  1869  ;  Altadore  Glen, 
Wicklow,  1873. 

PEDoroPHTLLtnc,  Lindberg. 

Jungermannia,  Nees,  Nat.  Europ.  Leber.  1,  p.  165  (1833).  Plagiochila, 
Dum.  Recueil,  1,  p.  15  (1835).  Pc^nophyllum,  Lindb.  Soc. 
Fauna  et  Fl.  Fenn.  (Oct.  1874),  and  in  Bot.  Not.  p.  156  (1874). 

Fedinophyllum  pyrenaieum,  Spruce.  Autoecious.  Tufts  dense, 
much  interwoven,  of  a  brownish  yellow  colour.  Stems  spread- 
ing, radiculose,  creeping  on  the  surface  of  earth  or  rocks  where 
they  grow,  sparingly  branched,  branches  axillary,  or  proceeding 
from  the  under  sui^ace  of  the  stem.  Leaves  somewhat  rigid, 
slightly  shining  when  dry,  densely  placed  on  the  stem,  and  di- 
stichous, broad  at  the  base  and  quadrate  towards  the  apex,  which 
is  variously  notched  and  toothed.  Amphigastria  very  small, 
and  likely  to  be  overlooked,  though  they  are  mostly  present, 
especially  near  the  points  of  barren  shoots,  1-3  parted,  segments 
subulate.  Involucral  bracts  much  larger  than  the  cauline  leaves, 
oblong-ovate,  slightly  emarginate  at  apex,  with  recurved  mar- 
gins. Colesule  compressed,  a  little  prominent,  short,  obovate-oval, 
mouth  broad  and  rounded,  lips  semi-oval,  irregularly  cut,  and 
dentate.  Andrcecium  terminal,  interruptedly  spicate,  on  same 
stem  as  the  fertile  shoots,  or  on  distinct  branches  on  same  plant. 


630  Proceedings  of  the  Royal  Irish  Academy. 

Perigonial    bracts    smaller,    imbricated,    bilobed.      Antheridia 
usually  solitary,  in  tbe  saccate  axils  of  the  perigonial  bracts. 

Plagiocbila  pyrenaica,  Spruce,  Hepat.  Pyren.  n.  9.  (1847),  and  in 
Trans.  Bot.  Soc.  Edinb.  ra.,  p.  200(1849);  Lindb.  Manipulus 
Muscorum  secundus,  in  Eaun.  et  Flor.  Fenn..  13,  p.  366  (1874). 
Plagiocbila  interrupta,  var.  p,  pyrenaica,  Carring.  Brit.  Hepat.  pL 
3,  figs.  2-9  (1874). 

Hab.  Sbady  rocks  and  banks,  mostly  in  limestone  districts.  On 
ratber  dry  banks  tbrougb  tbe  Benbulben  range,  Co.  Sligo,  wbere 
I  collected  it  for  the  first  time  it  was  found  in  Ireland  (1871) ; 
again  at  GlenifP,  in  same  district  (1875).  This  plant  may  be 
quoted  as  an  instance  of  the  difficulty  which  tbe  Hepatic®  present 
to  the  systematist,  in  not  affording  good  generic  characters,  that 
can  be  stated  in  words  which  will  enable  the  student  to  distin- 
guish them  clearly  one  from  the  other.  As  Dr.  Lindberg  well 
observes  in  his  description  of  this  plant  in  bis  Irish  Hepatic®, 
it  possesses  nothing  in  common  with  Plagiocbila,  except  the  com- 
pressed colesule.  The  affinities  are  altogether  with  the  Chilo- 
scyphiffi.  In  general  appearance  it  resembles  C.  polyanthos ;  yet 
it  approaches  even  more  both  in  habit  and  aspect  Saccogyna  yiti- 
culosa. 

Chiloscyphus,  Corda. 

Jungermannia,  Mich.  Nov.  PL  Gen.  p.  8,  tab.  5,  fig.  5  (1729); 
Linn.  8p.  PI.  1  ed.,  2,  p.  1131  (1753);  Hook.  Brit.  Jung.  (1816). 
MyHa,  B.  Gray,  in  Gray's  Nat.  Arr.  Brit.  PI.  1,  p.  693  (1821). 
Marsupella,  Dumort.  Comm.  Bot.,  p.  114  (1823).  Chiloscyphus, 
Corda,  in  Opiz,  Beitr.  1,  p.  651  (1829);  Dumort.  Syll.  Jung. 
Europ.,  p.  67  (1831). 

Involucral  bracts  imbricated  on  each  side  and  notched  at  the  margin. 
Colesule  rather  short  and  ^labiate,  the  lips  irregularly  notched, 
fruit  stalks  long,  pedicels  inarticulate,  rising  from  the  under  part 
of  the  stem. 

Chiloscyphus  polyanthos,  Corda.  Stems  prostrate,  growing  in  patches. 
Leaves  in  two  rows,  overlapping,  inclining  to  quadrate,  entire 
or  slightly  emarginate.  Amphigastria  bifid,  toothj&d  or  variously 
cut.     Colesule  short,  cleft  into  two  lips,  which  are  laciniated. 

Jungermannia  polyanthos,  Linn.  Sp.  PL  1597;  Hook.  Brit.  Jung, 
t.  62 ;  Lindenb.  Synop.  Hepat.,  p.  30.  Marsupella  polyanthos, 
Dumort.  Comm.  Bot.,  p.  1 14.  Chiloscyphus  polyanthos,  Corda,  in 
Sturm,  Deutschl.  Crypt.  19,  p.  33,  t.  9;  Dumort.  Syll.  Jung.,  p.  67, 
t.  1,  f.  9;  et  Jung.  Europ.,  p.  101;  G.  L.  et  N.  Synop.  Hepat., 
p.  188. 

Var.  p.  rividaris,  Nees.  Stems  dichotomous,  succulent.  Amphigastria 
sometimes  obsolete. 


Moore — On  Irish  Sepatic(B.  631 

Var.  y.  palleseerUf  Lindenberg. 

Hab.  On  wet  ground,  where  water  often  remains  during  a  considerable 
period  of  the  year. 

The  var.  ft,  rivularis  is  also  common  in  similar  situations.  Lindberg 
observes  that  the  infloresct^nce  of  this  variety  is  autcecious.  Var.  y. 
pallesccns  occurs  about  Killamey,  according  to  Dr.  Carrington, 
who  considers  there  is  no  valid  distinction  between  it  and  the 
typical  form.  Dumortier,  however,  gives  it  a  place  as  a  distinct 
species  (see  his  Hepat.  Europ.  p.  101  (1874)).  T.  Chandlee  finds 
it  also  near  Fermoy,  Cork. 

Habpanthtjs,  Nees. 

Jungermannia,  W.M.  Bot.  Taschenb.  p.  408  (1833);  Nees,  in  Flora,  16, 
p.  2,  p.  408  (1833).  Lophozia,  Dum.  Recueil,  1,  p.  17,  n.  19 
(1835).  Harpanthus,  Nees,  Nat.  Europ.  Leber.  2,  p.  351  (1836) ; 
Spruce,  in  Trans.  Bot.  Soc.  Edinb.  3,  p.  209  (1849) ;  Mitten,  in 
Joum.  L.  Soc.  8,  p.  52  (1864).  Pleuranthe,  Taylor,  in  Hook., 
Lond.  Joum.  Bot.  5,  p.  282  (1846). 

Colcsule  fusiform,  exserted,  3-4  cleft  at  the  mouth,  divisions  unequal, 
connate  at  the  base  with  the  calyptra.  Involucral  bracts  of  one  or 
two  pairs,  with  amphigastria  interposed.  Calyptra  adhering  to 
the  walls  of  the  colesule  for  more  than  half  its  length. 

HarpanthiM  icuiaius,  Spruce.  Dioecious.  Stems  mostly  crowded 
together  in  incoherent  tufts,  or  smaller  and  ccespitose,  quarter  to 
hfidf  an  inch  long  or  more,  ascending.  Leaves  succubous,  crowded, 
acutely  emarginate  at  the  apex.  Amphigastria  ovate-acuminate, 
slightly  toothed  at  the  base.  Colesule  obovate,  contracted  at  the 
mouth,  and  subplicate.  Calyptra  adherent  with  the  base  of  the 
colesule. 

Jungermannia  scutata,  Weber  et  Mohr,  Deutschl.  Crypt.,  p.  408 ; 
Lindenb.  Synop.  Hep.,  p.  38 ;  Dumort.  Syll.  Jung.,  p.  56,  excl. 
var.  y. ;  Taylor,  in  Fl.  Hib.  2,  p.  64 ;  G.  L.  et  N.  Synop.  Hepat. 
p.  101;  Rabenh.  Hepat.  Europ.  exsic.  218-466;  Cooke,  Brit. 
Hepat.,  p.  10,  tab.  72.  Jungermannia  stipulacea,  Hook.,  Brit. 
Jung.  t.  41 ;  Engl.  Bot.  tab.  2538  ;  Carring.,  Brit.  Hepat.  p.  49, 
pi.  7,  fig.  52 ;  Dumort.  Hepat.  Europ.  p.  67. 

Hab.  Moist  banks  and  on  rocks  among  the  larger  mosses,  &c.  This 
species  is  rather  local  in  Ireland,  and  confined  chiefly  to  the 
southern  counties.  Near  Bantry,  Cork,  Miss  Hutchins  (1812). 
Lough  Bray,  Wicklow,  Dr.  Taylor.  Killamey,  W.  Wilson,  Esq. 
At  Cromagloun  and  Glena,  Kerry ;  I  have  collected  it  during  my 
occasional  visits  to  these  places  at  various  times ;  also  at  Lough 
Bray,  Wicklow. 


632  Proceedings  of  the  Royal  Irish  Academy. 

Sub-tribe  4.     Saccootitkjs,  Dumortier. 

Inrolacral  bracts  wanting.  Colesolo  pendulous,  fixed  by  the  margm 
to  the  under  side  of  the  stem. 

KAVTiAy  Bennett,  Gray. 

Jungennannia,  Mich.  Nov.  PI.  Gen.,  p.  8,  n.  2,  tab.  5,  fig.  14  (1729); 
Dicks.  Fasc.  PL  Crypt.  Brit.  3,  p.  10,  tab.  8,  ^g.  5  (1793); 
Hook.  Brit.  Jung.  (1816).  Kantia,  B.  Gr.  in  Gray's  Nat.  Arr.  Brit. 
PI.  1,  p.  706  (1821).  Cincinnulus,  Dumort.  Comm.  Bot.  p.  115 
(1823).     Calypogeia,   Corda,  in  Opiz,  Beitr.  1,  p.  653  (1829). 

Colesule  dorsal,  oblong-acuminate,  lobed  at  the  mouth,  and  hairy, 
subterranean. 

1.  Kantia  trichomanis  (Dicks.),  B.  Gr.      Stem  procumbent,  branched. 

Leaves  succubous,  ovate,  entire  or  emarginate.  Amphigastria 
orbicular,  crenulato-emarginate. 
Jungermannia  trichomanis,  Dicks.  PI.  Crypt,  fasc.  3,  t.  8,  f.  5; 
Hook.  Brit.  Jung.  tab.  79 ;  Ekart,  Synop.  Jung.  p.  40,  tab.  4, 
fig.  35  ;  Fl.  Dan.  tab.  1896  ;  Engl.  Bot.  tab.  1875  ;  Taylor,  in 
Fl.  Hib.  2,  p.  64.  Calypogeia  fissa,  Raddi,  Mem.  Mod.  18, 
p.  44;  G.  L.  et  N.  Synop.  Hep.  p.  198.  Cincinnulus  tricho- 
manis, Dumort.  Syll.  Jung.  p.  72;  Kev.  Jung.  p.  21,  et  Hepat. 
Europ.  p.  15. 

Hab.  On  wet  shady  banks  and  woods.  Frequent  in  many  parts  of 
Ireland ;  very  abundant  about  Killamey. 

2.  J^n^t0ar^u^(N.  M.),  Lindb.    Dioecious.  Stem  elongated  near  the 

apex,  with  smaller  and  more  remotely  placed  leaves,  often  tipped 
with  gonidiferous  gemmae.  Leaves  roundish,  oblique,  apex 
bidentate,  fragile,  divergent.  Amphigastria  deeply  bifid,  segments 
subulate,  divergent. 

Calypogeia  arguta,  N.  M.,  in  Nees,  Europ.  Leber.  3,  p.  24,  n.  2; 
G.  L.  et  N.  Synop.  Hepat.,  p.  199,  n.  2;  Dill.  Hist.  Muse.  tab.  70, 
fig.  12 ;  Engl.  Bot.  tab.  1875.  Cincinnulus  argutus,  Dumort. 
Hepat.  Europ.  p.  117  (1874).  Kantia  arguta,  Lindberg,  in  Mani- 
pulu*  Muscorum  secundus,  p.  363,  Helsingfors  (1874). 

Hab.  On  wet  banks.  Very  rare  in  Ireland.  The  few  Irish  specimen* 
known  were  collected  at  Luggielaw,  Wicklow,  creeping  over  the 
stems  of  Nardia  compressa.  Dr.  Lindberg  detected  them  among 
my  specimens  when  examining  them. 

Saccootna,  Dumortier. 

Jungermannia,  Mich.  Nov.  PI.  Gen.,  p.  8,  tab.  5,  fig.  4  (1729);  Sm. 
Engl.  Bot.  tab.  2513  (1813) ;  Hook.  Brit.  Jung.  (1816).  lippia, 
B,  Gr.  in  Gray's  Nat.  Arr.  Br.  PI.  1,  p.  706  (1821).  Saccogyna, 
Dum.  Comm.  Bot.,  p.  1 13  (1823).  Sykorea,  Corda,  in  Opiz,  Beitr. 
1,  p.  653  (1829).     Calypogeia,  Raddi,  MSS.,  Corda,  in  Sturm, 


Moore — On  Irish  HepatkcB.  63* 

l)etit8chl.  PL  (1830).     Geocalyx,  Nees,  Nat.  Europ.  Leber.  1, 
p.  97  (1833). 

Inrolucral  bracts  wanting.  Colesnle  oblong,  fleshy,  fimbriated  at  the 
mouth  with  scales,  adhering  to  the  base  of  the  stem  by  its  mar- 
gin, and  pendulous. 

Saccogyna  vitieulosa  (Mich.),  Dumort.  Stem  procumbent,  branched. 
Leaves  succubous,  flat,  oyate,  entire.  Amphigastria  ovate-lanceo- 
late, dentate,  laciniate.    Colesule  subterranean. 

Jungcrmannia  viticulosa,  Linn.  8p.  PI.  1597  ;  Hook.  Brit.  Jung.  t.  60  ; 
Taylor,  in  PI.  Hib.,  p.  63;  Lindenb.  Synop.  Hepat.,  p.  28.  Sac- 
cogyna  viticulosa,  I)umort.  Syll.  Jung.,  p.  74 ;  Rev.  Jung.,  p.  22 ;. 
et  Hepat.  Europ.,  p.  117  ;  G.  L.  etN.  Synop.  Hepat.,  p.  194. 

Hab.  On  damp  ground,  among  mosses,  &c.  This  fine  species  is  of 
frequent  occurrence  in  many  parts  of  Ireland,  but  more  espe- 
cially in  the  south  and  west ;  very  fine  at  Lough  Bray,  Wicklow, 
and  in  the  woods  about  Killamey.  It  also  extends  to  the  coun- 
ties of  Antrim  and  Donegal  in  the  north,  and  Mayo  in  the  west. 


Sub-section  ff .  Acbooam^. 


*^  Stem  commonly  branched  by  innovations  proceeding  from  beneath 
the  perichfiBtmm,  rarely  pinnate  ( 


)  or  dichotomous.  Leaves  succubous, 
sometimes  conduplicate,  entire,  and  broken  up  in  capillary  seg- 
ments. Amphigastria  most  frequently  absent,  commonly  small 
and  ovate,  subulate,  rafely  larger,  and,  like  the  leaves,  undivided 
and  broken  up  into  capillary  segments.  GramoBcium  dioecious  or 
paroecious.  Perichsetium  apical  on  the  stem  itself  and  its  innova- 
tions. 

Colesule  rounded,  commonly  five-,  or  sometimes  more  densely,  pli- 
cate, not  unfrequently  compressed,  very  rarely  none.  Antheridia 
placed  in  the  highest  axils  of  the  stem  and  innovations.  Para- 
physes  present  in  some,  frequently  leaf -shaped." — Lindberg. 

Sub-tribe  5.     Blephaboziks. 

Tkichocolea,  Dumortier. 

Jungermannia,  Huds.  PI.  Angl.  1  ed.  p.  435  (1762);  Hooker,  Brit. 
Junger.  (1816).  Tricholea,  Dum.  Comm.  Bot.,  p.  113  (1823),  et 
Hep.  Europ.,  p.  11 1  (1831).  Tricholea,  Dum.  Syll.  Jung.  Europ., 
pp.  24  et  28  (1831).  Tiichocolea,  Nees,  Nat.  Europ.  Leber.  3, 
p.  103  (1838). 

Involucral  bracts  wanting.  Colesule  campanulate,  hairy,  mouth 
truncate,  without  teeth.     Capsule  4-valved.     Elaters  smooth. 


€34  Proceedings  of  the  Royal  Irish  Academy. 

TriehoeoUa  tomenteUa  (Ehrhart),  Dumort.  Stems  dichotomoos,  bi- 
tri-pinnate.  Leayes  unequally  2-lobed,  each  lobe  divided  and 
sub-divided  into  long  ciliary  fringes.  Amphigastria  cleft  into  two 
portions,  and  fringed  with  cilia.  Colesule  apical,  from  the  forks 
of  the  stem. 

Jungermannia  tomentella,  Ehrh.  Beitr.  2,  p.  150 ;  Dicks.  PI.  Crypt, 
fasc.  2,  p.  14 ;  Engl.  Bot.  t.  2242 ;  Hook.  Brit.  Jung.  t.  36 ;  Lin- 
denb.  Synop.  Hepat.,  p.  19  ;  Cooke's  Brit.  Hepat.,  p.  17,  fig.  129; 
Tayl.  in  Fl.  Hib.,  pt.  2,  p.  66.  Tricholea  tomentella,  Dumort. 
Hepat.  Europ.  p.  Ill  (1874) ;  G.  L.  et  N.  Synop.  Hepat.  p.  257. 

Hub.  Mossy  banks  in  woods  and  rocky  places.  Widely  distributed 
through  Ireland,  from  north  to  south,  and  east  to  west.  Very 
abundant  and  fine  in  the  Eillamey  woods. 

Blephabozia,  Dumortier. 

Jungermannia,  Linn.  Sp.  PI.,  p.  1601 ;  Hook.  Brit.  Jung.  (1816). 
Section  Blepharozia,  Dum.  Syll.  Jung.  p.  46  (1831).  Ptili- 
dium,  Nees,  Europ.  Leber.  1,  p.  95  (1833) ;  Petit  Thouars,  Veg. 
Afr.  Austr.  t.  1,  p.  11  (1806).  Blepharozia,  Dumort.  Rev.  Jung., 
p.  16  (1835). 

Involucre  oligophyllous,  2-3  lobed,  segments  with  long  cilia.  Cole- 
sule pear-shaped.     Mouth  small,  and  plicately  contracted. 

Blepharozia  ciliaris  (Linn.),  Dumort.  Stem  prostrate,  pinnate. 
Leaves  unequally  2-lobed,  overlapping,  lobes  ciliated,  deeply  cleft 
into  two  pointed  segments.  Fruit  lateral.  Colesule  obovate,  con- 
tracted and  toothed  at  the  mouth.  Amphigastria  broad,  quadrate, 
unequally  lobed,  and  ciliated. 

Jungermannia  ciliaris,  Linn.  Sp.  PI.  p.  1601 ;  Engl.  Bot.  t.  2241 ; 
Hook.  Brit.  Jung.  t.  65  ;  Lindenb.  Synop.  Hepat.  p.  1 9.  Blephar- 
ozia ciliaris,  Dumort.  Rev.  Jung.,  p.  16 ;  et  Hepat.  Europ.  p.  53 ; 
S.  0.  Lindberg  et  Lackstrom,  Hepat.  Scand.  fasc.  1,  n.  10.  Ptili- 
dium  ciliare,  Nees,  Europ.  Leber.  3,  p.  17;  G.  L.  et  N.  Synop. 
Hepat.  p.  230 ;  Rabenh.  Hepat.  n.  9-197. 

Hub.  Subalpine  rocks.  Brandon,  Kerry,  Dr.  Taylor.  Mangerton  and 
Ross  Bay,  Dr.  Carrington.  Tore  Mountain,  Blillamey,  1861. 
Rare  in  Ireland,  and  seemingly  confined  to  the  south. 

Mastioophoka,  Nees. 

Jungermannia,  Brid.  MSS.,  Web.  (F.),  Hist.  Muse.  Hep.  Prodr.  p.  56 
(1815);  Hook.  Bnt.  Jung.  p.  18  (1816).  Mastigophora,  Nees, 
Nat.  Eur.  Leber.  1,  p.  95  (1833);  Lindley,  Introd.  Nat.  Syst. 
Bot.,  2  ed.,  p.  414  ;  Mitt,  in  Hook.  Handb.  N.  Zealand  Fl.,  2,  pp. 
752-754  (1867).  Blepharozia,  Dum.  Recueil,  1,  p.  16  (1835). 
Sendtnera,  Endl.  Gen.  PI.  1,  suppl.  p.  1342  (1840).  Herberta, 
Carruth.  in  Seem.  Joum.  Bot.  3,  p.  300  (1865). 


Moore — On  Irish  Hepatiae,  635 

Miutigophora  Wbodsii  (Hook.),  Nees.  Stem  procumbent,  bi-tri-pin- 
nate,  long,  varying  from  three  to  six  inches  in  length.  Leaves 
much  overlapping,  roundish,  convex,  unequally  2-lobed,  the 
upper  lobe  cleft,  segments  ciliate-dentate.  Amphigastria  large, 
broader  than  the  stem,  cleft  into  two  spinulose-dentate  segments, 
with  a  spur  at  the  base  on  each  side. 

Jungermannia  Woodsii,  Hook.  Brit.  Jung.  t.  66 ;  Engl.  Bot.  suppl. 
t.  2668  ;  Lindenb.  Synop.  Hepat.  p.  20.  Blcpharozia  Woodsii, 
Dumort.  Recueil,  1,  p.  16;  et  Hepat.  Europ.  p.  54.  Mastigophora 
Woodsii,  Nees,  Eur.  Leber.  3,  p.  95 ;  S.  0.  Lindenberg  et 
Lackstrcim,  Hepat.  Scand.  fasc.  1,  n.  3.  Sendtncra  Woodsii, 
G.  L.  et  N.  Synop.  Hepat.  p.  241 ;  Rabenhor.  Hepat.  Eur. 
exsic.  n.  367-490. 

Hab.  On  subalpine  banks.  Mangerton,  Kerry,  Joseph  Woods,  Esq. 
Brandon,  Dr.  Taylor.  Carrantual,  Connor  Hill,  and  Brandon.  This 
fine  species  grows  in  large  patches  lying  flat  on  the  ground,  and 
appears  at  first  sight  to  resemble  patches  of  Thuyidium  tamarisc- 
inum,  Schimp.  In  Ireland  it  has  been  seen  growing  only  in  tho 
County  of  Kerry,  and  even  there  it  is  very  local. 

Hebbebta,  Bennett,  Gray. 

Jungermannia,  Sw.  Prodr.  Fl.  Ind.-Occ,  p.  144  (1788);  Dicks. 
Fasc.  PL  Crypt.  Brit.  3;  Hook.  Br.  Jung.  (1816).  Herberta, 
B.  Gr.  in  Gray's  Nat.  Arr.  Brit.  PI.  1,  p.  705  (1821) ;  Carruth.  in 
Seem.  Joum.  Bot.  3,  p.  300  (1865).  Schisma,  Dumort.  Comm. 
Bot.  p.  114  (1823).  Sendtnera,  sect.  1,  Schisma,  G.  L.  et  N. 
Synop.  Hep.  p.  239  (1845).    , 

Involucre  polyphyllous,  bracts  connate  at  their  base  with  the  perianth, 
variously  cleft  and  cut.  Colesule  tubular,  deeply  cleft  at  the 
mouth,  chartaceous  at  the  base. 

Serherta  adunca  (Dicks.),  B.  Gr.  Stems  erect,  growing  in  large 
patches  of  a  brown  colour,  from  two  to  six  inches  long.  Leaves 
deeply  bipartite,  falcato-secund.  Amphigastria  large,  bipartite. 
Fruit  terminal. 

Jungermannia  adunca,  Dicks.  Fasc.  PI.  Crypt.  Brit.  3,  p.  12,  tab.  8, 
f.  8.  J.  juniperinum,  var.  p,,  Hook.  Brit.  Jung.,  tab.  4.  Gym- 
nomitrium  juniperinum,  Corda,  in  Opiz,  Beitr.  p.  651.  Schisma, 
Dumort.  Syll.  Jung.  p.  76,  t.  2,  fig.  16  (1831);  et  Hepat.  Europ. 
p.  123  (1874).  Sendtnera  juniperina,  var.  )8.,  Nees,  in  G.  L.  et  N. 
Synop.  Hepat.  p.  239. 

Hab.  On  the  sides  of  mountains,  and  on  bogs.  Abundant  in  the  south 
and  west  of  Ireland,  but  not  common  in  the  nortlicm  or  eastern 
counties.  Gleniff  and  Glenad,  Co.  Leitiim.  Sir  W.  Hooker  remarks , 
in  his  British  Jungermannise  that  J.  juniperina  has  no  affinity 
to  any  other  British  species  of  Jungermannia,  which  remark  still 
holds  true.     Dumortier,  in  his  late  work  on  the  European  Hepa- 


636  Proceedings  of  the  Royal  Irish  Academy. 

ticae,  has  placed  it  in  his  tribe  Acolea,  along  with  Gymnomi- 
trium,  which  is  surely  unnatural,  when  the  whole  appearance 
of  these  plants  is  taken  into  consideration. 

Anthelia,  Dumortier. 
Jungermannia,  Linn.  Fl.  Lapp.  1  ed.  p.  342  (ITS?");  Hook.  Br.  Jung. 
(1816).     Anthelia,  Dum.  Recueil,  1,  p.  18  (1835).     Chandonan- 
thus,  Lindb.  in  Act.  Soc.  Sc.  Fenn.  10,  p.  19  (1871). 

Involucre  polyphyllous,  imbricated,  segments  sub-palmate.  Cole- 
sule  sessile,  cylindrical,  plicate  at  the  mouth,  and  denticulate. 

Anthelia  jtdacea  (Linn.),  Dumort.  Stem  erect,  branching.  Leaves 
deeply  bifid,  segments  acute,  imbricated  on  every  side  of  the 
stem.    Colesule  cylindrical,  subplicate,  and  toothed  at  the  mouth. 

Jungermannia  julacea,  Linn.  Sp.  PL  p.  1601 ;  Hook.  Brit.  Jung.  t.  2  ; 
Sm.  Engl.  Bot.  t.  1024;  Dumort.  Syll.  Jung.  p.  63;  Tay- 
lor, in  Fl.  Hib.  2,  p.  65  ;  Hiiben.  Hepat.  Germ.  p.  56  ;  G.  L.  et  N. 
Synop.  Hepat.  p.  140 ;  Babenhor.  Hepat.  Europ.  exsic.  n.  126— 
152.  Anthelia  julacea,  Dumort.  Hepat.  Europ.  p.  88,  tab.  3, 
fig.  23. 

Hab.  Bocks ;  usually  on  the  higher  mountains.  Maam  Tore  Moun- 
tain, Connemara ;  MacgiUicuddy's  Beeks,  Killamey ;  Kylemore, 
Co.  Galway.  Forma  minor,  on  Brandon  Mountain,  and  Connor 
HiU,  Kerry. 

Blephabostoma,  Dumortier. 

Jungermannia,  Linn.  Fl.  Suec,  1  ed.  p.  336,  n.  921  (1745);  Hook 
Brit.  Jung.  (1816).  Blepharostoma,  Dum.  Recueil,  1,  p.  18, 
n.  23  (1835).  Ptilidium,  Mitt,  in  Joum.  Linn.  Soc.  vol.  5,  p.  102 
(1861). 

Involucre  polyphyllous,  imbricated,  bracteoleB  articulate-ciliate. 
Leaves  transversal.  Colesule  sessile,  terminal,  erect,  round* 
ovate,  mouth  with  long  acute  cilia. 

1.  Blepharostoma  tricophylla  (Linn.),  Dumort.  Stem  creeping^ 
branched.  Leaves  imbricated  on  every  side,  deeply  3-4  parted, 
segments  setaceous,  jointed,  ascending.  Colesule  terminal, 
ovate,  contracted  and  ciliated  at  the  mouth. 

Jungermannia  tricophylla,  Linn.  Sp.  PI.  p.  1601 ;  Schmid,  Icones, 
p.  164,  t.  42 ;  Hook.  Brit.  Jung.  t.  7  ;  Corda,  in  Sturm,  Deutsch. 
Crypt,  fasc.  26,  p.  173,  t.  40 ;  G.  L.  et  N.  Synop.  Hepat.  p.  145; 
Babenhor.  Hepat.  Eur.  exsic.  n.  15-267.  Blepharostoma  trico- 
phylla, Dumort.  Rev.  Jung.  p.  18  ;  Cogn.  Hepat.  Belg.  p.  36. 

Hab.  On  turfy  heaths,  and  in  bogs  among  Sphagnum.  Belfast,  Mr. 
Templeton.  Bantry,  Miss  Hutchins.  Cromagloun,  Dr.  Carrington. 
Kylemore,  and  other  places  in  Connemara ;  Nephin  Mountain, 
Co.  Mayo.     This  pretty  plant,  which  is  so  unlike  any  other  Bri- 


Moore — On  Irish  Hepaticce,  637 

tish  species  save  the  following,  is  probably  more  generally  dis- 
tributed through  Ireland  than  it  is  known  to  be  at  present.  It 
frequently  grows  among  Sphagnum  and  other  mosses,  where  it  is 
not  readily  noticed. 

2.  Blepharostoma  setaeea  (Web.),  Mitt.  Stems  creeping.  Leaves  im- 
bricated round  the  stem,  deeply  bipartite,  the  segments  setaceous, 
jointed,  incurved.  Colesule  on  short  lateral  branches,  cylindrical, 
mouth  open  and  much  ciliated. 

Jungermannia  setaeea,  Weber,  Spicil.  Fl.  Gott.  p.  143;  Hook.  Brit. 
Junger.  t.  8 ;  Smith,  Engl.  Bot.  t.  2482  ;  Dumort.  Syll.  Jung, 
p.  63;  G.  L.  et  N.  Synop.  Hepat.  p.  144.  Blepharostema 
setaeea,  Dumort.  Bev.  Jung,  et  Hepat.  £urop.  p.  93.  Lepidozia 
setaeea,  Lindb.  Hepaticse  in  Hibemia  lectae,  p.  498  (1874). 

Hab.  Bogs,  and  moist  shady  banks  in  woods,  &c.  Very  abundant  in 
the  Killamey  woods,  and  many  other  parts  in  Co.  Kerry.  Less 
frequent  through  the  northern  and  eastern  counties.  On  moist 
banks,  parish  of  Basharkin,  Co.  Deny. 

Sub-tribe  6.    Jxhtgeemaknteje. 
IJolesule  and  calyptra  free.     Fructification  mostly  terminal. 

ScAFAFiA,  Dumortier. 

Jungermannia,  Mich.  Kov.  PI.  Gen.  p.  6,  tab.  5,  fig.  16  (1729); 
Linn.  Sp.  PL  1  ed.,  p.  1132  (1763).  Martinellia,  sect,  a,  in  Gray's 
Nat.  Arr.  Brit.  PI.  1,  p.  691  (1821).  Badula,  Dumort.  Comm. 
Bot.  p.  112  (1823);  Carruth.  in  Seemann's  Joum.  Bot.  3,  p.  301 ; 
sect.  2,  Lindenb.  in  G.  L.  et  N.  Synop.  Hepat.  p.  63.  Plagio- 
chila,  sect.  2,  ScapanisB,  Nees,  in  Lindb.  Introduct.  Bot.  2  ed. 
(1835). 

Fructification  terminal,  involucral  bracts  two,  larger  than  the  cauline 
leaves.  Colesule  compressed,  truncate  at  the  apex,  dentate  or 
entire,  decurved  at  first.  Capsule  quadrivalvous,  of  thickest 
texture.     Leaves  succubous,  bilobed.     Amphigastria  wanting. 

(a).  Lohea  of  the  leaves  suhequal» 

1 .  Seapania  eompactaf  Dumort.  Stems  procumbent,  short,  and  sparingly 
branched.  Leaves  conduplicate,  bilobed,  lobes  rounded,  entire. 
Involucral  bracts  denticulate.    Colesule  crenulate  at  the  mouth. 

Jungermannia  compacta,  Roth,  Germ.'  3,  p.  375;  Lindenb.  Synop. 
Hep.  p.  58.  Jungermannia  resupinata.  Hook,  Br.  Jung.  t.  23 
(excl.  syn.);  Sm.  Engl.  Bot.  tab.  2498. 

Hab.  Banks  among  heath,  &c.  Common,  Dr.  Taylor.  We  have 
not  found  it  te  be  a  common  species  by  any  means,  but  a  rare 
one  in  Ireland.  The  only  specimens  we  have  collected  of  the 
true  plant  are  from  the  neighbourhood  of  Brandon,  Co.  Kerry. 
Sterile  in  both  places  where  it  was  observed  growing. 


638  Proceedings  of  the  Royal  Irish  Jicademy. 

2.  Seapania  subalpina,  Dnmortier.     Far.  p.  unduli/olia.     Stems  sab- 

erect,  dichotomously  branched.  LeaTes  bifarious,  semi-amplexi- 
caul,  and  slightly  decurrenti  conduplicately  bilobed,  lobes  nearly 
equal. 
Jongermannia  subalpina,  Necs,  apud  Lindenb.  Hep.  p.  55  ;  Ekart, 
Synop.  Jung.  p.  27,  t.  11,  fig.  91.  Seapania  subalpina,  G.  L.  et 
li.  Synop.  Hepat.  p.  64,  var.  fi.  p.  65;  Dumort.  Rer.  Jung, 
p.  14  ;  Hcpat.  Europ.  p.  36. 

Hab.  Rivulets  where  the  water  is  constantly  trickling  oyer.  Lngna- 
quilla  Mountain,  Co.  Wicklow,  1864;  Nephinbeg,  Co.  Mayo, 
1862.  The  Irish  specimens,  var.  fi,,  have  the  stems  more  slender, 
radiculose  underneath.    liCaves  broader,  lobes  more  spreading. 

3.  Seapania  nimbrosay   Taylor.     Stems  ascending  or  erect,    slightly 

branched.  Leaves  bilobed,  imbricate,  dentate-dliate,  nearly  equal 

in  size,  lower  lobe  oblong-ovate,  patent. 
Seapania  nimbrosa,  Taylor,  in  Lehm.  Pugill.  Plant.  8  (1844),  p.  6; 

G.  L.  et  N.  Synop.  Hepat.  Europ.  p.  662;    Dumort.    Hepat. 

Europ.  p.  36 ;  Cooke,  Brit.  Hepat.  p.  6,  fig.  46. 
Hab.  Among  the  larger  mosses,    &c.      On  Brandon  Mountain,  Co. 

Kerry,  Dr.  Taylor.     I  know  nothing  of  this  plant  farther  than 

the  quotations  transcribed  testify, 

(h).  Leaves  hroader  ihanhng;  lobes  rounded  or  hlunL 

4.  Seapania  undulata  (Linn.,  Dill.),  Dumort.    Stems  ascending,  slightiy 

branched.  Leaves  unequally  2-lobed,  entire  or  denticulate,  loose, 
patent,  rounded,  trapezoidal,  of  flaccid  texture.  Fruit  terminal. 
Colesule  oblong-incurved,  mouth  truncate,  nearly  entire. 

Jungermannia  undulata,  Linn.  Sp.  PI.  1598 ;  Hook.  Brit.  Jung.  tab. 
22;  Sm.  Engl.  Bot.  t.  2251;  Nees,  Europ.  Leber.  1,  p.  184; 
Ekart,  Syn.  Jung.  p.  26,  t.  2,  ^g.  14.  Radula  undulata, 
Dumort.  Comm.  Bot.  p.  112.  Seapania  undulata,  Dumort. 
Jung.  p.  14  (1835)  ;  Hepat.  Europ.  p.  37  (1874);  G.  L.  et  N. 
Synop.  Hepat.  p.  65  (1844);  Gottsche  et  Kabenhor.  Hep. 
Eur.  exsic.  n.  194,  34,  90,  260,  291 ;  Cogn.  Hepat.  Belg.  p.  20. 

Hab.  Streamlets  among  the  hills.  This,  one  of  our  largest  and  finest 
British  species,  is  of  frequent  occurrence  in  Ireland.  The  steins 
sometimes  attain  to  the  length  of  3-4  inches,  and  are  generally 
of  a  purplish  colour,  or  of  a  bright  shining  green. 

Var.  p,  purpuraseens,  Hiiben.  Germ.  Hepat.,  is  common  in  Co.  Kerry. 

Far.  c.  speciosaf  Rabenhor.  Hep.  Eur.  exsic.  n.  442,  was  collected 
near  Lugnaquilla,  Co.  Wicklow.  A  very  large  and  unusual 
form  occurs  in  the  deep  lake  at  the  top  of  the  glen  leading  to 
Brandon  Mountain  from  the  Clogreen  side.  There  the  plant 
floats  in  deep  water,  and  has  black  wiry  stems  six  inches  or  more 
in  length,  with  intensely  green  leaves,  much  cut  and  lacerated  by 
aquatic  insects. 


Moore — On  Irish  ffepatica.  639 

5.  Seapanta  viiginoM  (Nees),  Dnmort.    Stems  ascending.  Leaves  con- 

duplicate,  unequally  bUobed,  the  lobes  roundish  and  entire  in  the 
margins,  larger  lobe  anteriorly  reclined,  smaller  about  one-fourth 
the  size  of  the  larger  lobe.     Colesule  entire  at  the  mouth. 

Scapania  uliginosa,  Dumort.  Ect.  Jung.  p.  14 ;  Hepat.  Europ.  p.  39 ; 
G.  L.  et  K.  Synop.  Hepat.  p.  67  ;  Cooke's  Brit.  Jung.  p.  6,  figs. 
44,  45. 

Hab.  Marshy  places  among  heath  on  the  mountains.  Near  the  Hunting 
Tower,  Cromaglaun  (1875) ;  Connor  Hill,  Co.  Kerry  (1873). 

6.  Seapania  irrigua,  Nees  (Dumort.)     Stems  creeping.    Leaves  bi- 

lobed,  conduplicate,  lobes  very  unequal,  anterior  lobe  much  the 
smallest,  and  curved  at  the  apex.  Involucral  bracts  bifid,  lobes 
nearly  equal.   Colesule  ovate,  compressed,  toothed  at  the  mouth. 

Jungermannia  irrigua,  Nees,  Europ.  Leber.  1,  p.  193.  Scapania  irri- 
gua,  Dumort.  Rev.  Jung.  p.  15 ;  Hepat.  Europ.  p.  37 ;  G.  L.  et  N. 
Synop.  Hep.  p.  67 ;  Carring.  Irish  Hepat.,  Trans.  Bot.  Edinb.  7, 
p.  447 ;  Cooke's  Brit.  Hepat.  p.  6,  fig.  47. 

Hab.  Marshy  wet  places  among  the  hills.  Knockavohlla,  Co.  Kerry, 
Dr.  Taylor.  Cromaglaun ;  Marsh  on  Benbulben,  Sligo ;  Lough 
Bray,  Wicklow.  This  plant  bears  more  of  general  resemblance  to 
S.  nemorosa  than  it  does  to  S.  undulata.  Only  small  portions  of 
it  were  collected  in  the  localities  mentioned. 

{c).  Leaves  longer  than  hroad  ;  lobes  more  or  less  acute, 

7.  Seapania  aquiloha,l)umoTt.    Dioecious.  Stems  loosely  tufted,  ascend- 

ing. Leaves  bilobed,  the  lobes  large,  nearly  equal,  dentate,  lower 
lobe  roundish-ovate,  apiculate.  Colesule  oblong,  compressed, 
mouth  oblique,  truncate,  denticulate,  scarcely  longer  than  the 
involucral  bracts.    Capsule  ovate. 

Jungermannia  aequiloba,  Schwaegr.  Prodr.  Hepat.  p.  214 ;  Ekart,  Synop. 
Jung.  1. 11,  fig.  90.  Radula  sequiloba,  Dumort.  Syll.  Jung.  p.  39. 
Scapania  aequiloba,  Dumort.  Rev.  Jung.  p.  14,  et  Hep.  Europ. 
p.  36 ;  G.  L.  et  N.  Synop.  Hepat.  p.  64 ;  Carring.  Brit.  Jung, 
p.  81,  n.  3,  pi.  8,  fig.  26,  exparU  (1^75). 

Hab.  Rocky  places  in  subalpine  countries.  Near  the  head  of  Gleniff, 
Co.  Leitrim  (1875),  growing  near  Saxifraga  nivalis.  This  is  the 
only  Lish  locality  I  feel  safe  in  quoting  for  this  species.  All  the 
other  Lish  specimens  I  have  seen,  which  have  been  named  8. 
SDquiloba  by  some  of  our  best  authorities,  are  states  of  Scapania 
resupinata,  Dumort.  =  Martinellia  gracilis,  Lindberg.  The  verru- 
cose  epidermic  layer  of  the  areolation  of  the  leaves,  first  observed 
and  pointed  out  by  Dr.  Lindberg,  seems  the  only  real  character 
by  which  this  plant  can  be  distinguished  from  its  near  allies. 

8.  Scapania  resupinata,  Dumort.    Dioecious.    Shoots  in  crowded  tufts 

for  the  most  part,  but  sometimes  more  lax  and  scattered,  mostly 

11.  I.  A.  PROC. — SER.  II.,  VOL.  II.,  baE>CE.  3  P 


640  Proceedings  of  the  Royal  Irish  Academy. 

fawn-coloured,  or  of  a  dirty  green.  Leayes  closely  imbricated  on 
the  stem,  bilobed,  lower  lobe  roundish,  apiculate,  reflexed,  the 
smaller  lobe  half  the  size  of  the  other,  roundish,  concave,  margins 
of  both  lobes  more  or  less  ciliately  dentate.  Colesule  truncate, 
dentate  at  the  mouth.     Capsule  oval. 

Jungermannia  resupinata,  Linn.  Sp.  PI.  1599 ;  Engl.  Bot.  t.  2437 
Tnon  Hook.);  Ekart,  Synop.  Jung.  p.  26,  t.  xi.  fig.  88  (excl. 
ng.  3).  Scapania  resupinata,  Dumort.  Eev.  Jung.  p.  14,  et  Hepat. 
Europ.  p.  34  ;  Carring.  Brit.  Junger.  part  4,  p.  77,  pi.  8,  fig.  26 
(ex parte)  ( 1 845).  Scapania  aequiloba,  var.  foliis  laevibus,  Gottsche, 
MSS.  Jens,  in  Bot.  Tidsskr.  2,  p.  288,  n.  47  (1868).  Martinellia 
gracilis,  Lindb.  in  Kot.  Soc.  F.  Fl.  Fenn.  13,  p.  365  (1874);  Acta 
Societatis  Scientiarum  Fennicse,  x.,  p.  520  (1875).  Jungermannia 
recurvifolia,  y.  recurvifolia,  Hook.  Jung.  t.  21,  f.  8. 

Hab.  Open  heathy  places  chiefly,  but  sdso  in  woods  and  among  rocks 
in  the  more  subalpine  parts  of  the  country.  Very  common  and 
widely  distributed  over  Ireland,  where  it  has  been  doing  duty  for 
Scapania  nemorosa,  which  latter,  so  far  as  I  have  seen  or  am  aware, 
is  rare  in  Ireland.  Dr.  Carrington  (in  British  Jungermanniae,  part 4, 
p.  79)  states  he  had  done  his  best  to  investigate  the  synonymy  of 
this  species,  having  devoted  several  days  to  it,  with  anything  but 
satisfactory  results.  To  me  the  results  appear  to  be  more  impor- 
tant than  they  do  to  the  author,  as  they  have  enabled  me  to 
understand  clearly  a  very  common  plant  in  Ireland,  which  I 
never  did  before,  nor  do  I  think  any  former  Irish  cryptogamic 
botanist  understood  it.  Dr.  Taylor's  Jungermannia  resupinata 
(inFLHib.p.  2,  p.  62)  is  Hooker's  plant  (figured  at  tab.  23,  Brit. 
Jung,  under  that  name)  =  J.  compacta,  Roth;  Scapania  compacta, 
Dumort.  Dr.  Taylor  certainly  considered  the  present  species  as 
a  state  of  nemorosa,  and  named  it  so  repeatedly.  Dumortier  has 
defined  Smith's  plant  during  a  considerable  number  of  years  past, 
both  in  his  Eecueil  Jungermannise  (1835),  and  Hepaticse  Europcc 
(1874).  Although  it  varies  much  in  size  according  to  locality,  it  is 
constaiit  to  its  leading  characters,  and  mostly  to  the  peculiar  fawn 
colour.  On  the  western  coast  of  Ireland,  I  have  seen  it  in  dense 
compact  patches,  nearly  half  a  yard  wide,  where  the  moist  winds 
from  the  Atlantic  were  favourable  for  its  growth.  On  Muckish 
Mountain,  Co.  Donegsd,  I  have  seen  it  tail  and  straggling  among 
the  heath  in  loose  stems,  quite  unlike  the  fawn-coloured  patches 
on  the  west  coast,  yet  easuy  recognizable  as  the  same  plant. 

9.  Scapania  nemorosa^  Dumort.  Dioecious,  rarely  autoecious.  Stems 
laxly  csespitose.  Shoots  more  or  less  erect.  Leaves  of  a  bright 
green  colour  when  fresh,  pale  green  when  dried,  unequally  bi- 
lobed, inferior  lobe  obovate,  recurved,  smaller  lobe  about  half  the 
size,  both  with  ciliate-dentate  margins.  Colesule  partly  immersed, 
mouth  truncate-ciliate. 


Moore — On  Irish  Hepaticce.  641 

Jungermannia  nemorosa,  Linn.  Sp.,  ed.  3,  p.  1598  ;  Engl.  Bot.  t.  607  ; 
Hook.  Brit.  Jung.  t.  21  (excl.  var.  omn.);  Taylor,  in  Fl.  Hib.  p.  2, 
p.  61 ;  Mart.  Fl.  Crypt.  Erlang.  p.  152,  t.  4,  fig.  28 ;  Lindenb. 
Synop.  Hepat.  p.  51 ;  De  Not.  Prim.  Hep.  Ital.  p.  10.  Kadula 
nemorosa,  Dumort.  Comm.  Bot.  p.  112.  Scapania  nemorosa,  Du- 
mort.  Rev.  Jung.  p.  14  (1835),  et  Hepat.  Europ.  p.  38  (1874) ;  G. 
L.  et  N.  Synop.  Hepat.  p.  68  (1844)  j  Carxing.  Brit.  Junger. 
part  4,  p.  74,  pi.  5,  fig.  15  (1875). 

Hab.  Damp  shady  banks  and  woods.  Woods  at  Kylemore,  Co.  Galway, 
and  at  Killamey.  Among  rocks  more  or  less  humid  at  Croma- 
glaun  and  Tore  Waterfall,  Kerry,  Dr.  Lindberg. 

10.  Seapania  planifolia,  Hook.  Stem  erect.  Leaves  quadrifariously 
imbricated  on  stem,  bipartite,  lobes  unequal,  inferior  largest,  ovate, 
superior  cordate,  margins  dentate-ciliate. 

J'ungermannia  planifolia,  Hook.  Brit.  Jung.  t.  67 ;  Engl.  Bot.  suppl. 
t.  2695 ;  Hook,  and  Tayl.  Muse.  Brit.  ed.  2,  p.  232  ;  Ekart.  Synop. 
Jung.  p.  23,  t.  10,  fig.  83.  Scapania  planifolia,  Dumort.  Bev. 
Jung.  p.  14 ;  Hepat.  Europ.  p.  40 ;  G.  L.  et  N.  Synop.  Hepat., 
p.  68. 

Hab.  On  high  mountains,  growing  among  the  large  mosses.  Brandon 
Mountain,  Co.  Kerry,  Dr.  Taylor  and  W.  Wilson,  Esq.  This 
extremely  rare  plant  has  not  been  found  in  any  other  locality  in 
Ireland  than  that  indicated.  During  my  several  visits  to  Brandon 
I  have  sought  for  it  there,  but  have  never  been  successful  in  find- 
ing it. 

11.  Scapania  umbrosa  {BchisAer),  Dumort.  Stem  short,  decumbent, 
slightly  branched.  Leaves  conduplicate,  unequally  bilobed,  infe- 
rior lobe  tapering  to  an  acute  point,  which  is  recurved,  smaller 
lobe  ovate-ligulate,  margins  sharply  serrate.  Colesule  incurved, 
compressed,  truncate  at  mouth.  Apex  of  shoots  frequently  co- 
vered with  a  dark  grumose  mass  of  gemmse. 

Jungermannia  umbrosa,  Schrader,  Samml.,   2,  p.  5 ;  Hooker,   Brit. 
Jung.  t.  24,  suppl.  3 ;   Engl.  Bot.  t.  2527;  Taylor,  in  Fl.  Hib. 
2,  p.  62.     Scapania  umbrosa,  Dumort.  Bev.  Jung.  p.  14,  ct 
lepat.  Euiop.  p.  38 ;  G.  L.  et  N.  Synop.  Hep.  p.  69. 

Hab.  Moist  rocks  and  banks.  Near  Dublin,  Dr.  Taylor.  Lough  Bray, 
Wicklow  ;  Kylemore,  Co.  Galway.  Frequent  in  the  Killamey 
woods,  especially  where  there  is  shade  and  moisture;  Brandon, 
Kerry. 

12.  Scapania  curta,  Dumort.  Stems  very  short,  ascending.  Leaves 
distichous,  unequally  bilobed,  inferior  lobe  largest,  roundish, 
apiculatc,  lobule  smaller,  acute,  erect,  and  spreading,  margins  of 
both  slightly  and  unequally  denticulate.  Colesule  terminal,  half 
immersed,  compressed,  mouth  truncate,  dentate. 

Jungermannia  nemorosa,  var.  8.  denudata,  Hook.  Brit.  Jung.  t.  21, 

3p  2 


L 


642  Proeeedingn  of  the  Royal  Irish  Academy. 

ff.  17~19.   Jangermannia  curta,  Mart.  Fl.  Crjpt.  Erlang.  p.  148,. 

L148,  t.  4,  fig.  24 ;  Lindenb.  8ynop.  Hep.  p.  56,  n.  52 ;  Nees, 
ber.  Eur.  1,  p.  214.  Badula  curia,  Dumort.  Syll.  Jun^^. 
p.  40.  Bcapania  curta,  Dumort.  Eer.  Jung.  p.  14  (1835),  et 
Hepat.  Europ.  p.  39  (1874);  G.  L.  et  N.  Sjnop.  Hep.  p.  69; 
Babenhor.  Hepat.  Eur.  exnc.  n.  395,  196,  382;  Cogn.  Hepat. 
Belg.  p.  22 ;  Caning.  Brit.  Jung,  part  4,  p.  86,  pi.  7,  fig.  23. 

Hab.  Moist  ahady  bankB,  in  wooda,  &c.  Silli^hbraes  and  Sleemish 
Mountain,  Co.  Antrim ;  Gleniff,  Co.  Leitiim ;  Benbulben  range, 
Sligo.  Abundant  at  Cromaglaun  and  other  places  about  the  £il- 
lamey  woods ;  wet  banks  near  the  sea,  on  an  island  off  Ballinakill 
harbour,  near  Letterfraek,  Co.  Galway.  This  species  and  S. 
umbrosa  are  often  found  together,  when  it  is  sometimes  difficult 
to  define  them. 

DiPLOPHTLLUv,  Dumorticr. 

Jungermannia,  Mich.  Nov.  PI.  Gen.  p.  8,  tab.  5,  fig.  9  (1729);  Linn. 
Fl.  Suec,  1  ed.,  p.  335  (1745)  ;  Hook.  Brit.  Jung.  (1816).  Biplo- 
phyllum,  Bum.  Kecucil,  l,p.  15(1835).  Scapania,  Mitt,  in  Hook. 
FL  Tasm.  2,  p.  233(1858). 

Involucre  oligophyllous.  Leaves  conduplicate,  bilobed.  Colesule 
round,  denticulate,  peduncle  inarticulate.  Capsule  quadrivalvcd, 
naked. 

1,  IHplophyUum  Mican%{J^xm,\  Tiumori.     Stems  ascending.    Leaves 

unequally  2-lobed,  conduplicate,  dorsal  lobe  ovate,  ventral  lobe 
larger,  oblong-ovato,  both  with  a  broad  pellucid  line  in  the  mid- 
dle. Colesule  terminal,  obovate,  contracted  at  the  mouth,  and 
toothed. 

Jungcrmannia  albicans,  Linn.  8p.  PL  p.  1599;  Hook.  Brit.  Jung, 
t.  23;  Engl.  Bot.  t.  2240 ;  G.  L.  et  N.  Synop.  Hepat.  p.  75  ;  Ba- 
benhor.  Hepat.  Europ.  exsic.  n.  13,  &c.  Diplophyllum  albicans, 
Dumort.  Rev.  Jung.  p.  16;  Hepat.  Europ.  p.  48;  Cogn.  Hepat. 
Belg.  p.  25. 

Hub.  Moist  banks,  and  in  shady  woods,  &c.  This  is  probably  the  most 
widely  diffused  and  commonest  species  in  Ireland.  It  varies 
much  in  size  and  appearance,  according  to  the  localities  where  it 
grows. 

2.  Diplophyllum   obtusifolium    (Hook.),   Dumort.     Dioecious.    Stem?v 

simple,  ascending.  Leaves  bif  arious,  conduplicate,  unequally  lobed, 
lobes  falcate,  rounded  at  the  apex.  Colesule  terminal,  plicate 
towards  the  apex,  which  is  contracted  and  toothed.  Antheridia 
in  the  axils  of  the  perigonial  leaves,  on  the  upper  portion  of  the 
male  plant. 
Jungermannia  obtusifolia,  Hook.  Brit.  Jung.  t.  26  ;  Smith,  Engl. 
Bot.  t.  2311  ;  Lindenb.  Synop.  Hepat.  p.  60;  Dumort.  Syll. 
Jung.    p.    46 ;    Ekart,    Synop.    Jung.   p.    30,    t.    7,    fig.    37, 


Moore — On  Insh  Sepaticce.  643 

H'ees,  Europ.  Leber.  1,  p.  237  ;  G.  L.  et  N.  Synop.  Hepat. 
p.  76 ;  Qottscho  et  Eabenhor.  Hepat.  Eur.  exsic.  n.  12-302. 
Diplophyllum  obtusifolium,  Dum.  Eev.  Jung.  p.  16,  et  Hepat. 
Europ.  p.  50  ;  Cogn.  Hepat.  Belg.  p.  24. 
Hab.  On  moist  clay  banks.  Near  Bantry,  Co.  Cork,  Miss  Hutchins 
(1812)?  Near  Dunkerron,  Co.  Kerry,  Dr.  Taylor.  Dunscome's 
Wood,  near  Cork,  W.  Wilson,  Esq.  (1829).  Very  rare  in  Ire- 
land. The  localities  quoted  are  the  only  places  where  it  has 
hitherto  been  observed. 

Plaoiochiljl,  Dumorticr. 

Jungermannia,  h.  Nov.  PL  Gen.  p.  7,  tab.  5,  fig.  1  (1729);  Linn. 
Sp.  PL,  1  ed.,  2,  p.  1131  (1753);  Hook.  Brit.  Jung.  (1816). 
Candollea,  sect.  A.,  Raddi,in  Att.  Soc.Modena,  18,  p.  22  (1818). 
Martinellia,  sect,  h,  in  Gray's  Nat.  Arr.  Br.  PL  1,  p.  692  (1821). 
Radula,  Dumort.  Comm.  Bot.  p.  112  (1823).  Plagiochila,  Dum. 
Recueil,  1,  p.  14  (1835)  ;  Lindenb.  Sp.  Hep.fasc.  1,  1-5  (1839) ; 
G.  L.  et  N.  Synop.  Hep.  p.  22  (1844). 

Involucral  bracts  two,  larger  than  the  cauline  leaves.  Colesule  com- 
pressed at  the  mouth,  ciliate-dentate.  Antheridia  in  the  angles 
of  perigonial  leaves.    Inflorescence  autoecious  or  dioecious. 

1.  Plagiochila  asplenioides  (Linn.),  Dumort.  Stems  ascending.  Leaves 
subimbricated,  obovate-rotund,  ciliate-dentate,  slightly  recurved 
at  apex.  Colesule  longer  than  the  involucral  bracts,  compressed, 
oblique,  mouth  truncate  or  ciliated. 

Jungermannia  asplenioides,  Linn.  Sp.  PI.  p.  1597  ;  Engl.  Bot.  1061 ; 
Hook.  Brit.  Jung.  t.  13  ;  Nces,  Europ.  Leber.  1,  p.  161.  Pla- 
giochila asplenioides,  Dumort.  Kev.  Jung.  p.  14;  G.  L.  et  N. 
Synop.  Hep.  p.  49 ;  Gottsche  and  Babenhor.  Hep.  Eur.  exsic. 
nos.  271-320;  Carring.  Brit.  Hepat.  p.  55,  pi.  4,  fig.  12;  Cooke, 
Brit.  Hepat.  p.  5,  fig.  37 ;  Dumort.  Hep.  Europ.  p.  43. 

Hab.  Banks  among  moss,  and  in  woods.  This,  one  of  the  largest  and 
finest  of  the  British  species,  is  common  all  over  Ireland.  In  the 
moist  shady  woods  at  Cromaglaun,  it  grows  to  a  very  large  size, 
where  the  stems  not  unfrequently  attain  from  8  to  10  inches 
long. 

Var.  p.  minor  {Plag,  JDiUenii),  Taylor,  in  Hook.  Journal  of  Botany,  p. 
260  ;  Trans.  Bot.  Soc.  Edinb.,  2,  p.  16.  Dumortier  enumerates  and 
describes  this  as  a  distinct  species  in  Hepat.  Europ.,  p.  43.  It 
grows  plentifully  in  the  Killamey  woods. 

Far.  S.  devexa,  Ross  Bay  and  Dingle  Bay,  Kerry,  Dr.  Carrington. 

2.  Plagiochila  tpinulosa  {J)ickB,)f  DmaoTt.  Stems  creeping,  branches 
ascending.  Leaves  ovate,  recurved,  oblique,  spreading,  wedge- 
shaped,  dentate-spinulose  on  ventral  aspect  and  apex,  entire  on 
dorsal  margin.  Fructification  lateral.  Colesule  roundish,  com- 
pressed, the  mouth  truncate-ciliated. 


644  Proceedings  of  the  Royal  IrUh  Academy. 

Jangermaimia  spinulosa,  Dicks.  Crjrpt.,  fasc.  2,  p.  14;  Hook.  Brit- 
Jung.  t.  14 ;  Engl.  Bot.  t.  2228  ;  Taylor,  Fl.  Hib.  2,  p.  58. 
Flagiochila  spinulosa,  Dumort.  Rev.  Jung.  p.  13,  p.  15,  et 
Hepat.  Europ.  p.  44  ;  Lindenb.  Sp.  Hep.  p.  6,  t.  1 ;  u.  L.  et  N. 
Synop;  Hepat.  p.  25 ;  Carring.  Brit.  Hepat.  p.  59,  pi.  4,  fig.  14. 
Martinellius  spiuulosus,  B.  Gray,  in  Gray's  Nat.  Arr.  Brit.  PI.  692. 

Hab.  Woods  and  moist  banks.  This  common  species  extends  over  the- 
whole  of  Ireland,  and  is  of  frequent  occurrence. 

Var,  y.  Carring.  Brit.  Hepat.  p.  60.  Glengarriff  and  Cromaglaun, 
Dr.  Carrington. 

3.  Plagiochila  punctata,  Taylor.  Dioecious.  Stems  closely  tufted,  of 
a  yellowish-green  colour.  Leaves  variable  in  size  and  shape, . 
rigid,  and  very  caducous,  especially  after  drying,  those  on  the 
main  shoots  broadly  ovate,  convex,  decurrent,  upper  margin  and 
apex  a  little  recurved,  fringed  with  spinose  teeth.  On  the  ulti- 
mate branches  the  leaves  are  narrower,  scarcely  wider  than  the- 
stem,  cuneiform  and  spreading,  their  margins  beset  with  from 
two  to  five  distant  teeth.  Cells  largely  collenchymatous,  yety 
smooth,  punctate — ^Dr.  Taylor  describes  their  appearance,  **  as- 
if  coarsely  powdered;"  Lindberg,  as  "  verrucolosis  striatulis."' 
Colesule  broadly  ovate,  from  a  narrow  base,  compressed  at  length,, 
cleft  at  side,  mouth  open,  beset  with  long  spinulose  teeth. 

Plagiochila  punctata,  Taylor,  in  London  Journal  of  Bot.  1844,  p.  371 
(sub.  n.  10),  et  1846,  p.  261 ;  Trans.  Bot.  Soc.  Edinb.,  p.  179^ 
G.  L.  et  N.  Synop.  Hep.  p.  626  ;  Dumort.  Hep.  Eur.  p.  45,  n. 
7  ;  Gottsche  et  Eabenlior.  Hep.  Eur.  exsic.  n.  211 ;  Lindb.  in 
Acta  Societatis  Scientiarum  Fennicee,  x.,  p.  524.  Plagiochila 
spinulosa,  p.  punctata,  Carring.  Irish  Crypt,  p.  19,  t.  2,  f.  3- 
(1863),  etBrit.  Hepat.  part  3,  p.  60. 

Hab.  Shady  woods,  and  banks  among  heath.  Abundant  in  the  Co. 
Kerry,  especially  in  the  Killamey  woods,  but  not  common  in  the 
northern  or  eastern  counties.  Altadore  glen,  and  at  Seven 
Churches,  Wicklow;  Glenad,  Co.  Leitrim. 

It  will  be  seen  from  the  authors  quoted,  that  considerable  diversity  of 
opinion  exists  as  to  the  right  of  this  plant  to  rank  as  a  distinct 
species.  Dumortier  and  Lindberg  hold  it  to  be  a  species,  while 
Carrington  considers  it  only  as  a  variety  of  P.  spinulosa.  I  have 
long  known  its  habit,  and  have  collected  it  in  widely  different 
habitats,  where  the  principal  characters  have  been  constant.  I 
have  sometimes  considered  it  nearer  to  P.  tridenticulata  than  to> 
P.  spinulosa. 

4.  Plagiochila  tridenticulata,  Taylor.  Stems  decumbent,  ascending  at 
apex,  flexuose,  slightly  branched.  Leaves  distant,  wedge-shaped, 
two  to  three  times  toothed  at  apex.     Andrcecium  spicate. 

Jungermannia  spinulosa,  fi,  tridenticulata,  Hook.  Brit.  Jung.  p.  9,  t. 
14;    Taylor,  in  Fl.  Hib.  2,  p.  58,  n.  10,  var.  minuta.     Plagio- 


Moore — On  Irish  Sepaticw.  645 

cliila  tridenticulata,  Duxnort.  Rev.  Jung.  p.  15,  et  Hepat.  Europ. 
p.  43 ;  G.  L.  et  N.,  Synop.  Hep.  p.  26  ;  Caning.  Brit.  Jung,  part 
3,  p.  63,  pi.  3,  fig.  10. 

Hab.  Moist  ground,  among  the  larger  mosses,  &c.  This  pretty  and 
distinct  species  is  mostly  confined  to  the  southern  counties  in  Ire- 
land, and  is  generally  scattered  in  small  tufts  among  other  herb- 
age. Cromaglaun,  Dr.  Taylor  and  Dr.  Carrington.  Brandon  and 
Connor  Hill,  Kerry. 

5.  Phigiochila  exigita^  Taylor.  Stems  straggling,  ascending,  slightly 
branched,  crowned  with  minute  capituH,  which  at  length  elongate 
into  new  shoots.  Leaves  round-obovate,  remote,  patent,  the  lower 
bifid,  nearer  the  apex  trifid,  or  ciliate.    Fructification  unknown. 

Jungermannia  exigua,  Taylor,  in  Trans.  Bot.  Soc.  Edinb.  1,  p.  179; 
Carring.  Brit.  Jung.  pi.  4,  fig.  13  (good).  Plagiochila  exigua, 
G.  L.  et  N.  Synop.  Hep.  p.  659  ;  Dumort.  Hepat.  Europ.  p.  46 ; 
Carring.  Brit.  Hepat.  pi.  4,  fig.  13  ;  Cooke,  Brit.  Jung.  p.  5, 
fig.  48  (bad). 

Hab.  About  the  bases  of  moss-covered  trees  at  Cromaglaun  and 
Killamey,  where  it  was  discovered  by  Dr.  Taylor,  who  de- 
scribed it  in  1843.  At  same  place,  1873,  where  it  is  not  rare; 
O'Sullivan's  Cascade,  and  Glena,  1875.  This  singular  and  very 
minute  plant  is  most  likely  to  be  observed  when  some  of  the 
larger  kinds  are  under  microscopical  examination ;  among  many 
of  these  it  frequently  makes  its  appearance  in  the  Killamey 
gatherings.  The  stems  are  seldom  more  than  one-fourth  of  an 
inch  long,  being  more  or  less  clothed  with  small,  distantly- 
set  leaves,  which  increase  in  size  as  they  approach  the  apex  of 
the  stem. 

Mtlia,  Bennett,  Gray. 

Jungermannia,  Hook.  Brit.  Jung.  p.  15,  n.  46,  47  (1816);  Dumort. 
Kecueil,  1,  p.  16,  n.  16  (1835).  Mylia,  B.  Gray,  in  Gray's  Nat. 
Arr.  Brit.  PL  1,  p.  693(1821).  Leptoscyphus,  Mitt,  in  Hook. 
Lend.  Joum.  Bot.  3,  p.  358  (1851).  Coleochila,  Dumort.  Hepa- 
ticae  Europas,  p.  105  (1874). 

Involucre  oligophyllous,  bracts  connate  at  the  base.  Colesule  terminal 
(or,  from  the  growth  of  innovations,  axillary),  cylindrical,  com- 
pressed at  the  apex,  mouth  cleft. 

1.  JK^/iaTbyfori  (Hook.),  B.Gray.  Dioecious.  Stems  ascending,  slightly 
branched.  Leaves  2-ranked,  succubous,  roundish,  concave,  reticu- 
lations large.  Amphigastiia  subulate.  Colesule  ovate,  slightly 
compressed  at  the  mouth,  truncate,  deeply  cleft  in  a  bilabiate 
form.     Antheridia  in  the  axils  of  perigonial  leaves. 

Jungermannia  Taylori,  Hook.  Brit.  Junger.  t.  34 ;  Engl.  Bot.  t.  2318 ; 
Lindenb.  Synop.  Hepat.  p.  24 ;    Dumort.  Syll.  Jung.  p.  48 ; 


646  Proceeding9  of  the  Boyal  Irish  Academy, 

Taylor,  in  Fl.  Hib.  p.  2,  p.  63 ;  G.  L.  et  N.  Sjnop.  Hepat.  p.  82. 
Coleochila  Taylori,  Dumort.  Hepat.  Europ.  p.  107. 

Hab.  On  wet  banks  in  Bubalpine  parts  of  the  country.  This  fine 
species  frequently  grows  in  large  patches  among  heath.  On  the 
damp  ground  near  mountain  rivulets,  where  its  purple-coloured 
tops  attract  the  cyo  of  the  collector,  even  when  at  a  oonsiderBble 
distance  from  the  plant. 

2.  Jfy/i«imom«/a(Hook.),  B.Gray.  Dioecious.  This  form,  with  the  leaves 
varying  from  roundish  concave  to  nearly  acuminate,  generally 
grows  among  Sphagnum.  The  late  Dr.  Taylor  did  not  consider  it 
was  even  a  variety.  Dr.  Carrington  thinks  differently,  and  de- 
scribes in  his  Irish  HepatiaB  a  character  by  which  it  may  be 
distinguished  from  M.  Taylori.  He  states,  ''  the  cells  are  of  a 
different  form  from  M.  Taylori,  containing  curious  fusiform  cor- 
puscles.'* Dumortier,  in  Hepaticn  Europe,  p.  106,  gives  it  the 
rank  of  a  species.  I  have  found  both  forms  frequentiy  growing 
together,  and  so  closely  resembling  each  other,  that  it  became 
a  difficult  task  to  separate  them. 

JuKoxaMAKKiA,  LinueuB. 
Jungermannia,  L.  Fl.  Suec,  I  ed.,  p.  338  (1745) ;  Raddi,  in  Att.  Soc 
Modena,  18,  p.  26  (1818);  Gray's  Nat.  Arr.  Brit.  PL  1,  p.  695 
(1821);  Dum.  Comm.  Bot.  p.  113  (1823).  Nitophyllum,  Neck. 
Elem.  Bot.  3,  p.  336  (1790).  Jungermannia,  sect.  1,  Diplophyl- 
lum,  Dum.  Syll.  Jung.  Eur.  p.  44  (1831);  sect.  3,  Aplozia,  do. 
p.  47  ;  sect.  4,  Gymnocolea,  do.  p.  52 ;  sect.  5,  Lophozia,  do.  p.  53 ; 
sect.  7,  Cephalozia,  do.  p.  60.  Diplophyllum,  Dum.  Recueil,  If 
p.  15  (1835) ;  Gymnocolea,  do.  p.  17  (1835) ;  Lophozia,  do.  p.  17 
(1835)  (excl.  L.  scutata);  Cephalozia,  do.  p.  18  (1835),  (sola 
C.  capitata) ;  Marsupella,  do.  p.  24  (sola  M.  MiQleri)  ( 1 835).  lio- 
chleena,  Nees,  in  G.  L.  et  N.  Syn.  Hep.  p.  150  (1845).  Solenostoma, 
Mitt,  in  Joum.  L.  Soc.  8,  p.  51  (1864). — ^lindberg. 

Section  A.     Aplozu. 

Involucre  oligophyllous.  Leaves  undivided,  entire.  Colesule  sessile, 
erect,  roiind  or  angular,  mouth  denticulate. 

1.  Jungermannia  (A.)  cuneifolia  (Hook.),  Dumort.  Stems  creeping* 
Leaves  distant,  cuneiform,  entire  or  bluntly  emarginate  at  the 
apex.     Amphigastria  minute,  bifid. 

Jungermannia  cuneifolia.  Hook.  Brit.  Junger.  t.  64;  Engl.  Bot. 
suppl.  t.  2700 ;  G.  L.  et  N.  Synop.  Hepat.  p.  153. 

Hab.  Parasitic  on  the  larger  Hepaticae,  especially  Prullania  tamarisci. 
Bantry,  Miss  Hutchins.  Tore  Mountain,  Dr.  Carrington.  On  the 
stems  of  trees,  creeping  over  F.  tamarisci,  between  the  police 
barrack  and  Upper  Lake,  Killarney.  This  singular  minute  species 
appears  to  be  confined  to  the  Killarney  district  of  Kerry.  It  mar, 
probably,  turn  out  to  be  a  Harpanthus  when  the  fruit  is  found  r 


MooRB — On  Irish  Hepaticm.  647 

2.  Jungermannia  {A,)  erenulata,  Smith  (Dumort.).  Steins  prostrate, 
branched.  Leaves  orbicular,  bordered  with  large  marginal  cells. 
Colesule  obovate,  compressed,  angled,  mouth  contracted,  toothed. 

^ungermannia  crenulata,  8m.  Engl.  Bot.  t.  1463 ;  Hook.  Brit.  Jung, 
t.  37 ;  Lindenb.  Synop.  Hepat.  p.  66 ;  G.  L.  et  N.  Synop.  Hepat. 
p.  90 ;  Taylor,  Fl.  Hib.  2,  p.  58.  Aplozia  crenulata,  Dumort. 
Hepat.  Europ.  p.  67  (1874). 

Hab.  On  moist  clay  banks  in  woods,  and  on  heaths.  Not  unfrequent 
through  Ireland.  Kelly's  Glen,  Dublin ;  side  of  the  river,  Seven 
Churches,  Wicklow;  Connemara;  Boss  Bay,  Kerry,  Dr.  Car- 
rington. 

Far.  p,  graeiUima,  Jungermannia  gracillima,  8m.  Engl.  Bot.  t.  2238 ; 
Hook.  Brit.  Jung.,  atdescript.  n.  37.  J.  genthiana,  Hiiben.  Hepat. 
Germ.  p.  107.     Aplozia  gracillima,  Dumort.  Hepat.  Europ.  p.  57. 

This  variety,  which  is  described  and  held  as  a  species  by  some  authors, 
gradually  approaches  the  typical  form  of  tiie  plant  in  some  of  its 
states.  It  is,  however,  usually  of  smaller  size,  with  the  leaves 
more  distantly  placed  on  the  stem,  and  more  amplexicaul  at  their 
base.  It  occurs  in  similar  places  as  that  of  the  larger  state  of  the 
plant,  but  at  Westaston,  Co.  Wicklow,  the  var.  ^.  is  ab^indant, 
and  none  of  the  true  A.  crenulata  grows  with  it. 

43.  Jungernuinnia{A^^pumila{yf\ih,\l^\imoTt,  Stems  ascending,  short, 
sub-simple.  Leaves  oblong-elUptic,  concave.  Colesule  terminal, 
fusiform,  plicate,  dentate,  ciliate  at  the  mouth. 

Jungermannia  pumila.  Wither,  Bot.  An.,  ed.  3,  p.  866;  Hook.  Briti 
Jung.  t.  17  ;  Sm.  Engl.  Bot.  t.  2230;  Tayl.  Fl.  Hib.  2,  p.  58. 
Aplozia  pumila,  Dumort.  Hepat.  Europ.  p.  59. 

Hab.  On  rocks  at  the  sides  of  streams  and  rivers,  not  rare.  Dr.  Taylor. 
Glen  near  the  Hunting  Tower,  Cromaglaun,  Dr.  Carrington. 
Connor  Hill  and  glen  at  Brandon,  Kerry ;  Lough  Bray,  Co.  Wick- 
low ;   Glenad,  Co.  Leitrim. 

4.  Jungermannia  [A,)  eordifolia  (Hook.),  Dumort.  Stems  erect, 
branching.  Leaves  incumbent,  coidate,  concave,  amplexicaul. 
Fruit  terminal  and  axUlair.  Colesule  plicate,  mouth  contracted, 
denticulate.  Antheridia  in  the  axils  of  perigonial  leaves,  spher- 
ical, reticulated. 

Jungermannia  eordifolia.  Hook.  Brit.  Jung.  t.  32;  Engl.  Bot.  t.  2590; 
Lindenb.  Synop.  Hepat.  p.  72;  G.  L.  et  N.  Synop.  Hepat.,  p.  93 ; 
Tayl.  Fl.  Hib.  2,  p.  58 ;  Babenhor.  Hepat.  Europ.  exsic.  nos. 
271-344.     Aplozia  eordifolia,  Dumort.  Hepat.  Europ.  p.  59. 

Hab.  Moist  banks,  and  on  the  rocky  bottoms  of  rivers  and  streams. 
Mangerton,  Co.  Kerry,  in  the  stream  from  the  Punch  Bowl,  Dr. 
Taylor.  River  which  flows  down  to  Cushindun,  Co.  Antrim, 
three-quarters  of  a  mile  above  the  village,  1836.  Coomashana 
lake,  Kerry,  Dr.  Carrington.  Brandon,  1864.  Maghanabo  glen, 
Kerry,  1875,  D.  Macardle.  This  distinct  and  well-marked  species 
is  rather  rare  in  Ireland. 


648  Proceedings  of  the  Royal  Irish  Academy. 

5.  Jung&rmannia  {A,)  ipharoearpa  (Hook.),  Dumort.      Stem  simple^ 

ascending.     Leaves  rather  distant,  accumbent,  orbicular,  entire. 

Colesule  terminal,  obovate,    contracted  at  the  mouth  and  cut 

into  four  large  teeth. 
Jungermannia  sphserocarpa,  Hook.   Brit.   Junger.  t.    74;    Lindenb. 

Synop.  Hepat.  p.  68;  Fl.  Dan.  t.   1773;    G.  L.  et  K  Synop. 

Hepat.  Europ.  p.  93  ;  Tayl.  Fl.  Hib.  2,  p.  68.     Aplozia  sphaero- 

carpa,  Dumort.  Hepat.  Europ.  p.  61.  • 
Hab.  On  stones  by  the  sides  of  rivulets.      Near  Dublin,  and  at  Tore 

Waterfall,  Killamey,  Dr.  Taylor.     Kelly's  glen,  Dublin ;  Lough 

Bray,  Wicklow ;  wet  rocks,  Glenad,  Co.  Leitrim. 

6.  Jungermannia  (A,)  riparia  (Taylor),  Dumort.     Stems  procumbent,, 

slightly  branched.      Leaves  obovate,  obtuse,  closely  set  on  the 

stem,  and  subamplexicaul,  concave,  entire.     Colesule  terminal,. 

obovate,  apex  plicate. 
Jungermannia  riparia,  Taylor,  in  Trans.  Bot.  Soc.  Edin.  p.  43 ;  G.  L. 

et  K.  Synop.  Hepat.  p.  97 ;  Cogn.  Hepat.  Belg.  p.  28 ;  Cooke's. 

Brit.  Jung.  p.  9,  fig.  69.     Aplozia  riparia,  Dumort.  Hepat.  Europ. 

p.  63. 
Hab.  Sides  of  streams  and  pools.     Kerry,  Dr.  Taylor.     Benbulben,. 

Sligo ;   Brandon,   Kerry ;    Loughbray,  and  near  Woodenbridge,. 

Wicklow.     Tore   Cascade,  Dr.    Carrington.     Enniscona,    Cork,. 

Isaac  Carroll,  Esq.     Dr.  Taylor  remarks  that  this  plant  has  been 

freqtiently  mistaken  for  J.  pumila.     When  strong  it  is  more 

likely  to  be  overlooked  at  first  sight  for  Chiloscyphus  polyan-^ 

thos. 

7.  Jungermannia  (A,)  nana,  'Kees.  Stems  ascending  or  erect,  pale  green,. 

radiculose,  branches  slender.  Leaves  round  or  roundish-ovate,, 
erect,  clasping.  Colesule  obtuse,  at  length  quadrangular  and 
slightly  crested,  mouth  toothed. 
Jungermannia  nana,  Nees,  Hep.  Europ.  1,  pp.  317,  278;  2,  p. 
466;  3,  p.  533;  4,  p.  41  ;  Gottsche,  Ic.  Hep.  ined.  Jungerman- 
nia pumila,  Lindenb.  Hep.  Europ.  p.  69,  n.  68,  t.  2  (excl. 
synon.) ;  De  Notar.,  Prim.  Hep.  Ital.  p.  38,  n.  48  ;  G.  L.  et  N. 
Synop.  Hepat.  Europ.  p.  91 ;  Carring.  Irish  Hepat.,  Trans.  Bot- 
Soc.  Edinb.  vol.  7,  p.  3,  p.  448.  Jungermannia  lurida,  Dumort- 
Hepat.  Europ.  p.  60  (1874).  Var.  a  major,  Jungermannia 
lurida,  Dumort.  Syll.  p.  60,  n.  49  (1831). 

Hab.  On  wet  banks,  by  the  sides  of  streams.  Glengariff,  Co.  Cork, 
Miss  Hutchins.  Kelly's  glen,  Co.  Dublin,  and  near  the  Sevea 
Churches,  Co.  Wicklow.  Apparently  rare  in  Ireland.  This 
little  plant  is  in  every  way  nearly  allied  to  Jungermannia  crenu- 
lata  and  J.  gracillima.  The  trigonal  colesule,  partly  crested  in. 
these  plants,  accords  with  the  character  of  Lindberg's  section  a, 
Eucalyx,  in  his  genus  Nardia  (emend.).  I,  however,  consider  them, 
more  naturally  placed  where  Dumortier  has  placed  them — ^in  his- 
section  Aplozia,  with  J.  sphserocarpa,  J.  pumila,  &c. 


MooBE — On  Imh  Hepaticcc.  64^ 

Section  B.     Sphjbnolobttm. 

8.  Jungermannia  (8.)  Dieksoni,  Hook.  Stems  ascending,  mostly  simple. 

Leaves  unequally  2-lobed,  lobes  narrow,  ovate,  acute,  entire  at 
the  margin,  ventral  lobe  much  the  largest.  Colesule  terminal, 
slightly  plicate,  and  subciliate  at  the  mouth.  Antheridia  in  the 
axils  of  perigonial  leaves. 

Jungermannia  Dicksoni,  Hook.  Brit.  Jung.  t.  48 ;  Engl.  Bot.  2591  ;. 
Taylor,  in  Fl.Hib.  p.  2,  p.  62;  Ekart.  Synop.Jung.  p.  52,  tab.  9, 
fig.  68 ;  G.  L.  et  N.  Synop.  Hep.  p.  79.  Diplophyllum  Dicksoni, 
Dumort.  Rev.  Jung.  p.  16,  etHepat.  Europ.  p.  49  (1875J  ;  Cogn. 
Hepat.  Belg.  p.  24. 

Hab.  On  rocks  and  moist  banks  in  subalpine  parts  of  Ireland.  Rare. 
Mountains  near  Dublin,  Dr.  Taylor.  Loughbray,  Co.  Wicklow, 
single  stems;  GlenifP,  Leitrim,  single  stems;  north  side  of 
Connor  Hill,  Kerry,  single  stems,  growing  among  the  larger 
mosses. 

9.  Jungermannia  {S.)  minuta,  Crantz.     Stems   erect,  dichotomously 

branched.  Leaves  patent,  bilobed,  lobes  nearly  equal,  acute  at  th& 
apex,  margins  entire.  Colesule  terminal,  subspherical,  mouth 
contracted,  denticulate.  Antheridia  in  the  axils  of  perigonial 
leaves,  several  together,  spherical,  reticulated. 

Jungermannia  minuta,  Crantz.  Hist.  Graen.  p.  288;  Hook.  Brit. 
Jung.  t.  44  ;  Sm.  Engl.  Bot.  t.  2231  ;  G.  L.  et  N.  Synop.  Hep. 
p.  120;  Taylor,  in  PI.  Hib.  p.  2,  p.  62.  Diplophyllum  minutuni, 
Dumort.  Rev.  Jung.  p.  16,  et  Hepat.  Europ.  p.  49;  Cogn.  Hepat. 
Belg.  p.  24. 

Hab.  Heathy  and  rocky  banks ;  rare  in  fruit.  Loughbray,  Co.  Wick- 
low ;  also  at  Seven  Churches,  Wicklow. 

Section  C.      Lofhozia,  Dumorticr. 

Involucre  oligophyllous,  multifid,  dissimilar  to  stem  leaves.  Cole- 
sule sessile,  erect,  round,  inflated,  contracted  at  the  mouth, 
and  dentate. 

(A,)  Stipulata, 

10.  Jungermannia  (Z.)  Bantriemis,  Hook.     Stems  subsimple,  erect  or 

ascending.  Leaves  roundish-oval,  emarginate  or  bidentate  at  the 
apex.  Amphigastria  minute,  entire,  or  slightly  toothed  on  the 
margin.     Colesule  obovate,  dentate  at  the  mouth. 

Jungermannia  Bantriensis,  Hook.  Brit.  Jung.,  in  annotatione  ad  J.  sti- 
pulaceam,  species  41 ;  Nees,  Europ.  Leberm.  2,  p.  24,  and  3,  p.  540  ; 
G.  L.  et  N.  Synop.  Hep.  p.  100  ;  Rabenhor.  Hep.  exsic.  n.  305  j 
Cooke,  Br.  Jung.  p.  10,  fig.  70 ;  Dumort.  Hep.  Europ.  p.  68. 


650  Proceedings  of  the  Royal  Irish  Academy. 

Hab.  Bantry,  Miss  Hutchins.  Olengariff,  Dr.  Ca]Tmg;toiL.  Brandon, 
Kerry ;  Benbolben,  Sligo ;  Gleniif ,  Leitrim. 

11.  Junyermannia{L,)H6m4€huehiana,l!feeB.  Stems  subsimple,  diffuse. 
Leaves  suborbiculate,  bidentate,  sinas  shaUow,  lobes  rathiT 
acute.  Amphigaatria  bifid,  divisioiis  lanceolate,  dUate-draUte 
at  base.  Colesule  long,  cylindrical,  mouth  acute,  gradually  ap- 
proaching to  triangular. 

Jungcrmannia  Homschuchiana,  Nees,  Europ.  Leberm.  2,  p.  153;  G. 
L.  et  N.  Synop.  Hepat.  p.  101 ;  Husnot,  Hepat.  Gall.  n.  32. 

Hab.  Wet  places  in  subalpine  parts  of  the  country.  At  Cromaglaao, 
Co.  Kerry,  and  among  rocks  near  Tore  Mountain,  July,  1869; 
stream  near  Woodenbridge,  Co.  Wicklow.  This  plant  is  rather 
larger  than  most  of  those  in  same  section,  and  might  be  easily 
passed  over  f or  J.  ( A. )  riparia,  both  in  a  fresh  and  dried  state.  It  is 
only  when  the  peculiarly  notched  sub-vertical  leaves  with  their 
amphigaatria  are  examined,  that  its  distinguishing  characters  arc 
observed.  Dr.  Liadberg  considers  J.  Hornschuchiana,  J.  Bantii- 
ensis,  and  J.  Miilleri  forms  of  one  species. 

12.  Jungermannia  (Z.)  Oreadensis,  Hook.  Stems  erect.  Leaves  closely 
imbricated,  erecto-patent,  incumbent,  appressed,  cordate-ovate, 
margins  recurved,  obtusely  emarginate  at  apex. 

Jungermannia  Orcadensis,  Hook.  Brit.  Jung.  t.  71 ;  Lindenberg,  Sp. 
Hep.  p.  74 ;  Nees,  Eur.  Leberm.  2,  p.  35  ;  G.  L.  et  N.  Synop. 
Hep.  p.  107 ;  Gottsche  et  Rabenhor.  Hep.  Eur.  exsic.  n,  40,  399, 
400 ;  De  Notar.  Prim.  Hep.  Ital.  p.  32.  Mesophylla  Orcadensis, 
Dumort.  Syll.  Jung.  p.  80  ;  Hepat.  Europ.  p.  130. 

Hab.  Among  the  larger  mosses  and  Hepatic®  in  subalpine  parts  of 
the  country,  but  very  rare  in  Ireland.  Brandon,  Co.  Kerry. 
"  Connor  Hill,  among  Herberta  adunca,  Dr.  Lindberg  (1873)." 

13.  Jungermannia  (Z.)  harbata,  Schreber.     Stems  ascending,  slightly 

branched.  Leaves  subquadrate,  3-5  cleft.  Amphigaatria  acutely 
bifid,  and  laciniated.  Colesule  ovate,  contracted  at  the  mouth,  and 
toothed.  Antheridia  in  the  axils  of  perigonial  leaves,  round, 
greyish,  and  slightly  reticulated. 

Jungermannia  barbata,  Schreber,  Spicil.  Lips.  p.  107 ;  Schmidel, 
Icones,  p.  187;  Hook.  Brit.  Jung.  n.  70;  Dumort.  SylL  Jung. 
p.  58;  Hepaticas  Europas,  p.  72  (1874).  J.  quinquidentata, 
Huds.  Angl.  Fl.  p.  511 ;  Schwaegr.  Prodr.  Hepat.  p.  29;  Sm. 
Engl.  Bot.  t.  2547 ;  Lindenb.  Synop.  Hepat.  p.  45  ;  Ekart,  Syn. 
n.  47,  tab.  5,  fig.  41 ;  De  Not.  Prim.  Hep.  Ital.  p.  22.  Lophoziu 
barbata,  Dum.  Rev.  Jung.  p.  17 ;  Cogn.  Hepat.  Belg.  p.  31. 

Hab.  Among  rocks,  and  on  heathy  banks.  This  plant  is  of  general 
occurrence  in  Ireland,  from  the  northern  to  the  southern  counties, 
and  from  east  to  west ;  but  most  abundant  in  the  north,  especially 
in  counties  Antrim  and  Donegal. 


Moore — On  Irish  Hepaiicte.  651 

Var.  p.  Floerhix,  Leares  connivent.  Amphigastria  long  and  laciniate^ 
jnngermannia  Floerkii,  Web.  et  Mohr,  Deutechl.  Crypt,  p.  410 ;: 
Mart.  Erlang.  p.  144,  t.  4,  f.  17.    Muckish,  Donegal. 

(-5.)  Ex'StipuJata, 

14.  Jungerfnannia  (Z.)  Lytmi,  Taylor.  Stems  ascending,  sparingly 
branched.  Leaves  alternate,  distichous,  subquadrate,  recurved 
trifid,  anterior  lacinse  roundish,  posterior  reflexed,  all  acute  or 
incised,  terminal  tooth  large.  Amphigastria  wanting.  Involucral 
bracts  rather  long.  Colesule  oblong,  obtuse,  inflated  at  the  baso^ 
near  to  the  middle,  mouth  plicate-ciliate. 

Jungermannia  Lyoni,  Taylor,  in  Trans.  Bot.  Soc.  Edinb.  1,  p.  116,. 
tab.  7;  Spruce,  in  Trans.  Bot.  Soc.  Edinb.  3,  p.  204;  Dumort!^ 
Hepat.  Europ.  p.  73  (1874).     J.  socia,  var.  y.,G.  L.  et  N.  Synop 
Hep.  p.  112.     J.  barbata  var.  G.  L.  et  N.  /.  c,  p.  678. 

Hab.  On  rocky  banks  among  mosses.  At  Glenmaluer,  Co.  Wicklow, 
among  tufts  of  Scapania  resupinata,  single  stems.  It  will  be 
observed  from  the  foregoing  quotations,  that  considerable  diver* 
sity  of  opinion  prevails  regarding  the  position  this  plant  ought  to 
occupy,  whether  as  a  species,  or  only  as  a  variety  of  J.  barbata. 
Dr.  Spruce's  critical  observations,  which  always  deserve  the  great- 
est attention,  would  appear  to  be  decisive  on  the  point,  namely, 
that  it  is  a  good  species.  He  never  found  the  true  J.  barbata  in 
the  Pyrenees,  though  he  found  J.  Lyoni. 

15.  Jungermannia  (Z.)  exseeta,  Schmidel.  Stems  prostrate.  Leavca 
2-ranked,  spreading,  ovate-lanceolate,  bilobed,  and  cut  at  the- 
margin,  lobes  very  unequal,  sharp  at  apex.  Involucral  bracts 
quadrifld.     Colesule  terminal,  plicate.' 

Jungermannia  exseeta,  Schmid.  Ic.  et  Anal.  p.  241,  t.  62,  fig.  2,  excl. 

fig.  fructf.  et  19,  20  ;    Hook.  Brit.  Jung.  t.  19,  and  suppl.  t.  1  ; 

Taylor,  in  Fl.  Hib.  p.  2,  p.  62  ;  G.  L.  et  N.  Synop.  Hepat.  p.  77 ; 

Gottsche  et  Rabenhor.  Hep.  Eur.  exsic.  n.  130,  358;  Dumort. 

Hepat.  Europ.  p.  73. 
Hab.  Banks,  and  in  old  woods.   Bantry,  Co.  Cork,  Miss  Hutchins.   On 

dry  banks  common,  Dr.  Taylor.     Rotten  bogs,  Cromaglaun,  Dr. 

Carrington.    Ballinhassig  glen,    Co.  Cork,  Isaac  Carroll,    Esq. 

Gleniff,  Leitrim ;  Sillaghbraes,  Antrim, 

16.  Jungermannia  (Z.)  intermedia,  Lindenb.     Stems  ascending,  slightly 

branching.  Leaves  in  two  rows,  erect,  roundish  in  outline,  bifid 
segments  acute.  Involucral  bracts  3-5  lobed,  inciso-dentate,  con-^ 
nate  at  base,  appressed.  Amphigastria  wanting.  Colesule  ter- 
minal, obovate. 

Jungermannia  excisa,  var.  crispa.  Hook.  Brit.  Jung.,  p.  11,  tab. 
suppl.  2.    Jungermannia  bicrcnata,  var.  minor,  Mart.  El.  Crypt. 


^52  Proceedings  of  t/ie  Royal  Irish  Academy. 

Erlang.,  p.  168.  Jimgermannia  intermedia,  Lindenb.  Synop. 
Hepat.,  p.  83 ;  Dumort.  Syll.  Jung.  p.  55 ;  Ekart,  Synop.  p.  15, 
tt.  6,  12,  fig.  46;  Nees,  Europ.  Leberm.,  2,  p.  125;  Gtottsche 
et  Rabenhor.  Hep.  Eur.  exsic,  n.  60,  144,  312 ;  Dumort. 
Hepat.  Europ.  p.  76.  Lophozia  intermedia,  Dumort.  Key.  Jung, 
p.  17. 

Hab.  Bogs  and  banks  in  subalpine  parts.  On  Galtymore  Mountain, 
Co.  Tipperary. 

1 7 .  Jungermannia  (Z. )  eapitata,  Hook.  Stems  prostrate,  rather  crowded. 
Leaves  erect,  roundish-quadrate  in  outline,  the  lower  bifid,  the 
upper  crowded,  resembling  involucral  bracts,  3-5  incised,  and 
cleft.     Amphigastria  wanting.     Colesule  terminal,  oval. 

Jungermannia  capitata.  Hook.  Brit.  Jung.  t.  80.  Jungermannia  in- 
termedia, var.  capitata,  Nees,  Europ.  Leberm.,  2,  p.  125. 

Hab.  Dry  mountain  rocks.  Near  Bantry,  Miss  Hutchins,  who  sent  it 
to  Hooker.  (Brit.  Jung.,  n.  80).  Some  of  the  best  authorities 
on  Biitish  Hepaticee  consider  this  and  the  previous-named  species 
to  be  the  same.     I  am  not  well  acquainted  with  either. 

18.  Jungermannia  (Z.)  ventricosaj  Dicks.  Stem  ascending,  slightly 
branched.  Leaves  accumbent,  subquadrate,  obtuse  or  bluntly 
cmarginatc,  concave.  Involucral  bracts  3-4  cleft.  Amphigastria 
wanting.  Colesule  ovate-oblong,  contracted  at  the  mouth  and 
slightly  toothed. 

Jungermannia  ventricosa,  Dicks,  PI.  Crypt.   2,  p.   14;  Hook.   Brit. 

Jung.  t.  28  ;  Engl.  Bot.  t.  2568 ;  Tayl.  in  Fl.  Hib.  2,  p.  60 ;  G. 

L.  et  N.  Synop.  Hepat.  p.  108;   Rabenhor.  Hepat.  Europ.  exsic. 

n.  184,  185. 
Hab.  Banks  and  rocks  in  mountain  situations,  Dublin  and  Wicklow. 

Conemore,  Dr.  Taylor.   Antrim ;   Benbulben,  Sligo ;  Galtymore, 

Tipperary.  Rare  at  Killamey,  Dr.  Carrington. 

19.  Jungermannia  (Z.)  excisa,  Dicks.  Stem  prostrate.  Leaves  patent, 
subquadrate,  deeply  emarginate.  Fruit  terminal.  Colesule 
oblong-ovate,  the  mouth  wide,  plicate,  and  toothed. 

Jungermannia  excisa,  Dicks.  PI.  Crypt.  3,  p.  11,  t.  8,  fig.  7;  Hook.  Biit. 
Jung.,  p.  11  (excl.  syn.  Mohr,  Wahlcn.,  Schwaegr.,  and  Smith 
also  var.  which  is  in  Suppl.  t.  2) ;  Lindenb.  Synop.  Hep.  p.  84 
Nees,  Europ.  Leberm.  2,  p.  98 ;  Q.  L.  et  N.,  Synop.  Hep.  p.  112 
Dumort.  Hepat.  Europ.  p.  78.     Lophozia  excisa,  Dumort.  Rev! 
Jung.,  p.  17. 

Hab.  "Woods  and  heathy  banks.  Rare  in  Ireland.  On  the  mountains 
near  Dublin,  Dr.  Taylor.  This  plant  has  not  turned  up  among 
the  widely  extended  gatherings  made  by  me  in  many  parts  of  Ire- 
land, nor  have  I  seen  Irish  specimens  of  it. 

20.  Jungermannia  {Z.)bicrenata,  Lindenb.  Stems  procumbent,  subsim- 
pie.  Leaves  roundish-ovate,  acutely  emarginate.  Involucried  bracts 


Moore — On  Irish  Hepaticce.  653 

appressed,  trifidy  sub-serrulate.    Amphigastria  wanting.    Cole- 
sule  ovate, 

•Jnngennannia  bicrenata,  Lindenb.  Synop.  Hepat.  p.  82 ;  Nees, 
Europ.  Leberin.  2,  p.  119;  G.  L.  et  N.  Synop.  Hepat.,  p.  116; 
Dumort.,  Hepat.  Europ.,  p.  78.  Jungermannia  excisa,  Sm. 
Engl.  Bot.  t.  2497  (excl.  syn.) ;  Ekart,  Synop.  Jung.  t.  11, 
fig.  93. 

Hab.  On  the  ground  among  heath,  and  on  shady  banks.  Temple 
Michael,  Cork,  Isaac  Carroll,  Esq.  ;  near  Letterfrack,  and 
Kylemore,  Co.  Galway  (1874). 

:21.  Jungermannia  (Z.)  incisa,  Schrader.  Stems  prostrate,  subsimple. 
Leaves  accumbent,  roundish-quadrate,  undulate,  trifidly  cut,  the 
segments  unequal.  Involucral  bracts  3-4  incised.  Amphigastria 
wanting.     Colesule  terminal,  obovate,  mouth  toothed. 

Jungermannia  incisa,  Schrader,  Samml.,  2,  p.  5 ;  Hook.  Brit.  Jung, 
t.  10;  Engl.  Bot.  t.  2528;  G.  L.  et  N.  Synop.  Hepat.  p.  118; 
Ihimort.  Syll.  p.  66 ;  Hepat.  Europ.  p.  80  ;  Taylor,  in  Fl.  Hib. 
2,  p.  61.  Lophozia  incisa,  Dumort.  Rev.  Jung.  p.  17;  Cogn. 
Hepat.  Belg.  p.  30. 

Sab.  On  the  wet  sides  of  turfy  banks.  Rare  on  the  eastern  and 
northern  sides  of  Ireland ;  more  abundant  on  the  western,  par- 
ticularly in  Connemara;  Corslieve  Mountain,  andBengore,  Mayo; 
near  Kylemore,  Galway ;  abundant  on  the  top  of  Mulrea  Moun- 
tain, Mayo.     Near  Cooneashana  lake,  Kerry,  Dr.  Carrington. 

Section  D.     Gtmnocolea,  Dumortier. 

Involucre  oligophyllous,  bracts  bifid.  Colesule  pedunculate,  mouth 
denticulate. 

22.  Jungermannia  {G.)  laxifoUa  (Hook.),  Dumort.  Stem  lax,  filiform, 
prostrate.  Leaves  remote,  ovate,  acutely  bifid,  segments  acute, 
erect.  Colesule  subterminal,  often  from  the  axil  of  a  young 
branch,  subplicate,  mouth  contracted,  denticulate. 

Jungermannia  laxifolia,  Hook.  Brit.  Jung.  t.  69  ;  Engl.  Bot.  t.  2677  ; 
Lindenb.  Synop.  Hepat.  p.  34 ;  Taylor,  in  Fl.  Hib.  p.  66 ;  G. 
L.  et  N.  Synop.  Hepat.  p.  147;  Rabenhor.  Hep.  Europ.  exsic. 
n.  343.  Gymnocolea  laxifolia,  Dumort.  Rev.  Jung.  p.  17,  et  Hepat. 
Europ.  p.  64. 

Hab.  On  rocks  by  the  sides  of  rivulets.  Near  Bantry,  Miss  Hutchins. 
Castlekelly  Mountain,  Dublin,  and  Aooreagh  river,  near  Sneera, 
Kerry,  Dr.  Taylor.  Maghanabo  glen,  Connor  Hill,  and  Brandon, 
Kerry.  Cromaglaun  and  Mangerton,  Dr.  Carrington.  This 
minute  plant  adheres  closely  to  the  rocks  on  which  it  grows,  and 
looks  more  like  a  minute  Alga  than  a  Hepatic. 


654  Proceedings  of  the  Royal  Irish  Academy. 

23.  Jungerwumnia  {O.)  injiata  (Huds.),  Dumort.     Stem  ascending, 

branched.     Leaves  2-ranked,  acutely  bifid,  the  segments  obtnse. 
Colesule  terminal,  oblong-ovate,  month  contracted  and  toothed. 

Jangennannia  inflata,  Huds.  Flor.  Angl.  p.  511 ;  Hook.  Brit.  Jung, 
t.  38 ;  Lindenb.  Sjnop.  Hepat.  p.  79 ;  De  Notaris,  Prim.  Hepat. 
Ital.  p.  29 ;  Taylor,  in  Fl.  Hib.  2,  p.  59 ;  O.  L.  et  N.  Synop. 
Hepat.  p.  105;  Rabenhor.  Hepat.  Europ.  exsic.  n.  174—311,  &€. 
Oymnocolea  inflata,  Dumort.  Kev.  Jung.  p.  17,  et  Hepat.  Enrop. 
p.  63. 

Hab.  On  stones  by  rivulets ;  but  oftener  on  moors  about  the  roots  of 
heath.  Bantry,  Miss  Hutchins.  Abundant  on  the  moors  at 
Featherbed  Mountain,  Co.  Dublin.  Near  Finglas,  Dublin,  Mr.  D. 
Macardle. 

Var.  a.  compaeta,  Carrington.  On  the  top  of  Howth  Hill,  Dublin, 
where  it  grows  among  dry  rocks  and  is  green,  not  having  the 
usually  black  colour  of  the  species. 

Var.  y.  laxa.  Near  Lough  Guitane,  and  near  Dean  Bridge.  Boss  Bay, 
Kerry,  Dr.  Carrington. 

24.  Jungermannial^O,)  affinis (Wilson),  Dumort.  Stem  small,  procum- 
bent. Leaves  rounded,  concave,  bifid,  segments  obtuse,  reticula- 
tion large  and  hyaline.  Involucral  bracts  larger  than  the  caulinc- 
leaves,  spreading,  and  slightly  reflexed.  Colesule  terminal, 
pyriform,  contracted,  plicate,  and  toothed  at  the  mouth. 

Jungcnnannia  affinis,  Wilson,  in  Hook.  Brit.  Fl.  2,  p.  128.  Jnnger- 
mannia  turbinata,  Wils.  in  Engl.  Bot.  suppl.  t.  2744,  nee  Haddi; 
Taylor,  in  Fl.  Hib.  2,  p.  59.  Jungermannia  Wilsoniana,  Noes, 
Europ.  Lebenn.  3,  p.  548;  Cooke,  Brit.  Jung.  p.  10,  f.  74. 
Oymnocolea  affinis,  Dumort.  Hepat.  Europ.  p.  65. 

Hab.  Woodlands,  near  Dublin,  W.Wilson,  Esq.,  1830.  Not  nnfrc- 
quent  on  the  grey  limestone  in  the  Co.  Dublin,  where  it  fruits 
freely.  Finglas  quarry,  Mr.  D.  Macardle.  On  white  limestone 
near  Glenarm,  Co.  Antrim.  Killamey,  on  limestone,  Dr.  Carring- 
ton. Tore  Cascade,  Killamey,  and  a  larger  state  of  the  plant  on 
Carrantual,  Kerry. 

Naebia,  Bennett,  Gray. 

Jungermannia,  Ehrh.  in  Hann.  Mag.  p.  141  (1784);  Schrad.  Syst. 
Samml.  Krypt.  Gew.  2,  p.  4(1797);  Sm.  Engl.  Bot.  tab,  1463 
(1805);  Hook.  Brit.  Jung.  (1816).  Nardia,  B.  Gray,  in  Graves 
Nat.  Arr.  Brit.  PI.  1,  p.  701  (1821);  Lindb.  in  Act.  Soc.  Sc. 
Fenn.  x.,  p.  115  (1871);  sect.  1,  Eucalyx,  Lindb.  in  Bot.  Not. 
(1872).  Mesophylla,  Dum.  Comm.  Bot.  p.  112  (1823).  Mar- 
supella,  Dum.  Comm.  Bot.  p.  114  (1823),  et  Recueil,  1,  p.  23. 
n.  37  (1835).  Sarcoscyphus,  Corda,  in  Opiz,  Beitr.  1,  p.  652 
(1829);  Sturm,  Dcutschl.  Fl.  2,  fasc.   19,   20  (1830).      Alien- 


Moore — On  Irish  HepatkcB.  655 

laria,  Corda,  in  Opiz,  Beitr.  1,  p.  652  (1829).  G^ymnoinitrinm, 
Nees,  Nat.  Enr.  Leber.  1,  p.  120  (1833);  Solenostoma,  Mitt,  in 
Joum.  Lin.  8oc.  8,  p.  51  (1864). 

Section  A.    Massupella  (Dnm.),  Lindberg. 

Colesnle  connately  united  with  tbe  inyolucral  leaves  and  torus,  toge- 
ther forming  an  urceolate  perianth.  Capsule  globose.  Elaters 
with  two  spires.  Antheridia  in  the  saccate  bases  of  the  perigonial 
leaves. 

1.  Nardia  emarginata  (Ehrh.),  B.  Gr.   Stem  erect.    Leaves  distichous, 

imbricated,  patent,  obcordate,  ema2^;inate. 
Jungermannia  emarginata,  Ehrh.  Beitr.  3,  p.  80;  Sm.  Engl.  Bot. 

t.  1022 ;  Hook.  Brit.  Junger.  t.  27 ;  Taylor,  in  Fl.  Hib.  2,  p.  59; 

Fl.  Daoica,  t.  1945,  f.  1.  Nardius  emarginatus,  B.  Gr.  in  Gray's 

Nat.  Arr.  Br.  PI.   1,  p.  694.     Marsupella  emarginata,  Dumort. 

Comm.  Bot.,  p.  114;  Eev.  Jung.  p.  24,  et  Hepat.  Europ.  p.  126. 

Sarcoscyphus  Ehrharti,  Corda,  in  Opiz,  Natural.,  p.  652 ;  G.  L. 

et  N.  Synop.  Hepat.  p.  6  ;  Nees,  Eur.  Leberm.  1,  p.  125. 
Hab.  Wet  rocks  and  sides  of  mountain  rivulets.    Very  frequent  in 

Ireland.     Several  distinct  forms  or  varieties  which  retain  their 

habits  as  to  size,  colour,  &c.,  occur  occasionally. 

Var.  y.  minor  was  found  sparingly  on  rocks  near  the  police  barrack  at 
Cromaglaun,  in  1873. 

2.  Nardia  iphaeelata,  Giesecke.     Stem  erect,  branched.    Leaves  di- 

stichous, not  BO  closely  imbricated  as  in  the  previous  species,  patent, 
obovate-emarginate,  rounded  at  the  acute  apex. 

Jungermannia  sphacelata,  Giesecke,  in  Lindenb.  Synop.  Hep.  p.  76, 
t.  1,  fig.  9;  Ekart,  Synop.  Jung.  p.  15,  tab.  11,  fig.  91.  Mar- 
supia  sphacelata,  Dumort.  Syll.  Jung.  p.  78.  Sarcoscyphus  spha- 
celatus,  Nees,  Europ.  Leber,  p.  129 ;  G.  L.  et  N.  Synop.  Hepat. 
p.  7 ;  Rabenhor.  Hepat.  Europ.  exsic.  n.  519-255.  Marsupella 
sphacelata,  Dumort.  Hepat.  Europ.  p.  127. 

Hab.  Wet  rocks  by  the  borders  of  mountain  rivulets.  Very  rare. 
Loughbray,  Wicklow,  according  to  Dr.  Carrington  (British  He- 
paticffi,  p.  12),  who  states  that  Dr.  Lindberg  collected  it  there  in 
1873,  growing  with  Nardia  compressa.  I  have  never  seen  an 
Lish  specimen  of  this  plant,  though  Lindberg  states,  that  it  was 
collected  by  me  at  Loughbray,  Wicklow. 

3.  Nardia  Funekii  (Web.  et  Mohr),  Carring.     Stem  erect,  densely 

tufted,  slightly  branched.  Leaves  distichous,  obovate,  rounded, 
concave,  acutely  emarginate. 
Jungermannia  Funekii,  Web.  et  Mohr,  Deuts.  Krypt.  p.  422 ;  Lindenb. 
Synop.  Hepat.  p.  77 ;  Ekart,  Synop.  Jung.  p.  14,  t.  13,  fig.  112. 
Sarcoscyphus  Func^,  Nees,  Europ.  Leberm.  1.  p.  135 ;  G.  L. 
et  N.  Synop.  Hepat.  p.  8 ;   Babenhor.  Hep.  Europ.  exsic.  n. 

S.  I.  A.  PKOC,  BXB.  n.,  VOL.  11.,  80IBNCB.  3  Q 


656  Proceedings  of  the  Royal  Irish  Academy. 

86-254.  Marsupella  Funckii,  Dumort  EeT.  Jong.  p.  24,  et 
Hcpat.  Europ.  p.  128. 

Hub.  On  moist  Bhady  banks,  and  argillaceons  rocky  places.  Black 
Mountain,  near  Belfast  (1837) ;  mountains  aboTe  Kylemore  lake, 
Co.  Galway  (1874). 

4.  Nardia  revoluta  (Nees),  lindb.     Stem  matted,  flagOliferous  at  the 

base,  densely  tufted.  Leaves  obovate-eUiptic,  imbricated,  semi-am- 

plezicaul  at  the  base,  reflexed  at  the  margin,  acutely  emaiginate. 
Sarcoscyphus  revolutus,  Nees,  Leberm.  Eur.  2,  p.  419;    G.  L.  etN. 

8ynop.  Hep.  p.  8.     Marsupella  revoluta,  Dumort.  Hepat.  Europ. 

p.  126.     Nardia  reyoluta,  Carring.  OreVillea,  n.  18,  p.  88,  fig. 

19-25  (1873) ;   Brit.  Hepat.  p.  22 ;   landb.  Bevis.  Crit.  FL  Dan. 

p.  113(1871). 
Hab.  On  rocks  at  Luggielaw,  Wicklow,  Mr.  David  Orr  (1851).    Not 

found  by  any  other  person  in  Ireland.  This  rare  plant  I  collected 

in  some  quantity  on  rocks  above  Jerkin  station,  on  the  Dottc- 

field,  Norway,  in  1864. 

Section  B.     Mssopbtlla,  Dumortier. 

5.  Nardia  sealari*  (Schrader),  B.  Or.    Dioecious.      Stem  ascending, 

radiculose.  Leaves  two-ranked,  accumbent,  roundish,  entire,  or 
rarely  subemarginate.  Amphigastria  broadly  subulate.  Invo- 
lucre urceolate. 

Jungermannia  scalaiis,  Schrad.  Samml.  2,  p.  4 ;  Hook.  Brit.  Jung.  t. 
61 ;  Lindenb.  Synop.  Hepat.  p.  28 ;  Nees,  Europ.  Lebenn.  p.  281. 
Mesophylla  scalaris,  Dumort.  Comm.  Bot.  p.  112;  Eev.  Jung, 
p.  24.  Alicularia  scalaris,  Corda,  in  Opiz,  Natural,  p.  653 ;  6. 
L.  et  N.  Synop.  Hep.  p.  10 ;  Gottsche  et  Rabenhor.  Hep.  Europ. 
exsic.  n.  69,  70,  232-381 ;  Dumort.  Hepat.  Europ.  p.  131 ;  Nar- 
dius  scalaris,  B.  Gr.  in  Gray's  Nat.  Arr.  Br.  PL  1,  p.  694,  n.  1 
(1821);  Carrington,  Brit.  Hepat.  p.  23. 

Hab.  On  moist  clay  banks,  among  heath  and  other  herbage.  Very 
abundant  throughout  Ireland.  It  varies  considerably  in  form 
according  to  the  nature  of  some  localities  where  it  grows.  A  very 
remarkable  form,  the  var.  13.  rivularis,  Lindb.,  grows  in  very  wet 
places  under  the  constant  spray  of  little  cascades,  or  running 
water,  where  its  clear  glistening  leaves  are  very  conspicuous.  It 
has  frequently  been  named  Jung,  hyalina  by  some  of  our  mo^t 
acute  and  well  practised  hepaticists. 

6.  Nardia  compressa  (B.   Gr.),   Carrington.     Stem  erect,   branched, 

laterally  compressed.  Leaves  succubous,  two-ranked,  orbiculate, 
compressed,  subulate.  Amphigastria  sometimes  present  at  the 
points  of  young  shoots.  Calyx  immersed  among  the  involucral 
leaves,  mouth  toothed. 
Jungermannia  compressa,  Hook.  Brit.  Jung.  t.  58 ;  Sm.  Engl.  Bot. 
t.  2587 ;  Lindenb.  Synop.  Hep.  p.  33.    Mesophylla  compressa, 


Moore — On  Irish  Hepatkcs.  657 

Dnmort.  Comm.  Bot.  p.  112;  Syll.  Jung.  p.  80,  t.  2,  etHepat. 
Europ.  p.  129.  Alicularia  compressay  G.  L.  et  N.  Synop.  Hep. 
p.  12;  Eabenlior.  Hepat.  Eniop.  exsic.  n.  443,  472,  587. 
iN'ardia  compressa,  Carrington,  Brit.  Hepat.  pi.  3,  fig.  9. 

Hab.  Sides  of  rivnlets,  and  moist  rocky  places  near  waterfalls.  Local 
in  Ireland,  and  chiefly  confined  to  the  Co.  Wicklow,  on  the  east 
side,  and  Kerry  on  the  south-west.  First  discovered  by  Miss 
Hutchins,  near  Bantry,  Cork.  At  Aooreagh  river,  near  Sneem, 
Dr.  Taylor.  Abundant  at  Upper  Loughbray,  more  sparingly  at 
Luggielaw  and  Seven  Churches,  Wicklow ;  Kelly's  glen,  Dublin ; 
Connemara — near  Kylemore,  Galway. 

Var.  p.  rigida,  Lindb.  Near  to  N.  sphacelata,  but  stems  shorter,  narrower, 
and  more  rigid,  more  branched,  more  densely  foliaceous,  and  here 
and  there  flexuose.  Leaves  more  spreading  and  rigid.  Cells  twice 
the  size,  and  thickened,  generally  highly  coloured. 

Hab.  Loughbray,  Co.  Wicklow,  Dr.  Lindberg.  On  boggy  land  near 
Seven  Churches,  Co.  Wicklow. 

Dr.  Lindberg  states  that  this  form  is  intermediate  between  the  typical 
form  of  the  species  and  its  var.  v.  Carringtonii;  (Adelanthus  Car- 
ringtonii,  Balfour,  MSS. ;  Nardia  Cairingtonii,  Lindb.  The  fii-st 
plants  of  this  which  I  collected  were  sent  to  Dr.  Lindberg,  who 
named  them  N.  Carringtonii  without  any  reservation. 

Section  C.     Sotjthbta,  Spruce. 

7.  Nardia  ohovata  (Nees),  Carrington.  Stems  ascending,  clothed 
with  purple  rootlets.  Leaves  roundish,  obovate,  patent,  base 
contracted  and  somewhat  saccate,  alternate  on  lower  portion  of 
stem,  opposite  at  apex.  Involucral  leaves  connate  more  than 
half  way  with  the  colesule,  the  upper  portion  of  which  is  free, 
mouth  toothed. 

Jungermannia  obovata,  Nees,  Europ.  Leberm.  1,  p.  332;  2,  p.  474;  G. 
L.  et  N.  Synop.  Hepat.  p.  95,  n.  44 ;  Fl.  Danica,  suppl.  t.  118, 
n.  2 ;  Carring.  Tr.  B.  Soc.  Ed.  7,  p.  447 ;  Cooke,  Brit.  Jung.  p.  8, 
fig.  62.  Jungermannia  tersa,  Nees,  Europ.  Leberm.  p.  471 
{exparte)y  et  Synop.  Hepat.  p.  94  {ex  parte).  Southbya  obovata, 
Dumort.  Hepat.  Europ.  p.  133.  Na]^a  obovata,  Carring.  Brit. 
Hepat.  p.  32,  pL  11,  fig.  35. 

Hab.  Moist  rocks,  and  by  the  sides  of  rivulets.  Tore  Mountain,  Kil- 
lamey,  W.Wilson  (1829).  Lough  Bray,  Co.  Wicklow. 

Var,  p,  minor ^  Cromaglaun,  KiUamey,  Dr.  Carrington,  Irish  Crypt,  in 
Trans.  Bot.  Soc.  Edinb.  7,  part  3,  p.  447,  pi.  2,  fig.  1.  Connor 
Hill,  Kerry ;  streams  above  Kylemore  lake,  Co.  Galway. 

S.  Nardia  hyalina  (Lyell),  Carrington.  Polyoecious.  Stem  flexuose, 
creeping,  ascending  at  the  apex.     Leaves  roundish,  subcrenulate 

dQ2 


658  Proceedings  of  the  Royal  Irish  Acadettiy. 

at  the  margin,  erecto-patent,  entire.  Colesule  subtenninal,  oblong, 

angulate,  mouth  contracted,  toothed. 
Jungermannia  hyalina,  Lyell,  in  Hook.  Brit.  Jung.  tab.  65 ;  lindenb. 

Synop.  Hepat.  p.  67 ;  Dumort.  Syll.  Jung.  p.  50 ;  G.  L.  et  N. 

Synop.  Hepat.  p.  92 ;  Cooke,  Brit.  Jung.  p.  8,  fig.  61 ;    Engl. 

Bot.  Buppl.  t.  2678.     Aplozia  hyalina,  Dumort.  Hepat.  Europ. 

p.  58.     f^ardia  hyalina,  Carring.  in  Brit.  Hepat.  p.  35,  pi.  11, 

fig.  36. 
Hab.  Moist  banks,  and  by  the  sides  of  streamlets  in  rocky  places. 

Seefing  Mountain,  Dublin.     Aooreagh  river,  near  Sneem,  Kerry, 

Dr.  Taylor,  in  Fl.  Hib.     Brandon,  W.  Wilson,  Luggielaw,  and 

Seven  Churches,  "Wicklow.     Kot  very  common  in  Ireland. 

Adelakthus,  Mitten. 

Jungermannia,  Dicks.  PI.  Crypt.  (1783).  Hook.  Brit.  Jung.  (l816); 
Radula,  sect.  3,  Plagiochila,  Dum.  Syll.  Jung.  Europ.  p.  43 
(1831).  Plagiochila,  Dumort.  Eecueil,  1,  p.  15  (1835).  Gym- 
nanthe,  Mitten,  in  Journal  Linn.  Soc.  p.  166  (1863).  Adelanthus, 
Mitten,  in  Journal  Linn.  Soc.  7,  p.  243  (1864).  Odontosehisma, 
Lindb.  Soc.  Faun,  et  Fl.  Fenn.  13,  pp.  357-363  (1874). 

Perianth  on  short  ventral  shoots  at  the  base  of  the  branches,  tubulosc, 
mouth  connivent,  subtrigonous,  dentate.  Involucral  bracts  tri- 
farious.  Antheridia  in  the  axils  of  perigonial  leaves  which  are 
spicate.  Stems  procumbent  below,  stoloniferous,  leafless,  branches 
erect,  curved,  simple.  Leaves  distichous,  almost  vertical,  dorsal 
margin  decurrent. 

Adelanthus  decipiens  (Hook.),  Mitten.  Dioecious.  Stem  erect,  the 
upper  leaves  subcompresscd,  larger,  rotundate,  the  lower  ovate, 
aU  of  them  marginate,  reticulated  with  irregular  spiniform 
teeth.  Amphigastria  thick,  short,  subulate.  Colesule  on  short 
ventral  shoots,  tubulose,  ventricose,  mouth  connivent,  ciliate- 
dentate.  Antheridia  in  the  axils  of  perigonial  leaves  of  tbe  male 
plant. 

Jungermannia  decipiens.  Hook.  Brit.  Jung.  tab.  50 ;  Engl.  Bot.  2566 ; 
Nees,  Hep.  Eur.  1,  p.  159.  Plagiochila  decipiens  Dumort.  Rev. 
Jung. ;  G.  L.  et  N.  Synop.  Hepat.  p.  24 ;  Gottsche  et  B:abenhor. 
Hepat.  Eur.  p.  213.  Lindenb.  Spec.  Hep.  p.  51,  n.  29,  tab.  12, 
figs.  1-3.  Eadula  decipiens,  Dumort.  Syll.  Jung.  p.  43,  p.  15. 
Gymnanthe  decipiens,  Mitt.,  Joum.  of  Linn.  Soc.  7,  p.  166. 
Adelanthus  decipiens.  Mitt,  in  Joum.  of  Linn.  Soc.  7,  p.  244 ; 
Gottsche  et  Rabenhor.  Hepat.  Eur.  exsic.  n.  474  (ctun  icone) 
excellent. 

Hab.  Eocky  and  heathy  places  near  Bantiy  (Miss  Hutchins),  KQ- 
lamey,  near  GlcngarifE  (Dr.  Carnngton).    Glenad,  Leitnm. 


Moore — On  Irish  Hepati€(».  659 

CssiA,  Bennett,  Gray. 

Jungcrmannia,  lightfoot,  Fl.  Scot.  2,  p.  786  (1770);  Hook.  Brit. 
Junger.  (1816).  Cesia,  B.  Gray,  in  Gray's  Nat.  Air.  Brit.  PI.,  l,p. 
706  (1821);  Carrutli.  in  Seem.  Journ.  Bot.  3,  p.  300  (1865). 
Scliisma,  Dumort.  Comm.  Bot.  p.  114  (1823).  Gjrmnomitrium, 
Corda,  in  Opiz,  Beitr.  1,  p.  651  (1829) ;  Nees,  Nat.  Eur.  Lcberm. 
1,  p.  113  (1833).  Sect.  1,  Julacea,  G.  L.  et  N.  Synop.  Hep.  p.  2 
(1844).  Acolea,  Dumort.  SyU.  Jung.  Eur.  p.  76  (1831),  et  Re- 
cueil,  1,  p.  23  (1835). 

Involucral  leaves  several,  Colesule  wanting.  Bases  of  the  pistiUidia 
immersed  in  the  hollow  apex  of  the  stem.  Antheridia  axillary. 
Amphigastria  none. 

Cesia  erentdata  (Gottsche),  Camith.  Stems  erect  or  depressed, 
of  a  dirty  white  or  brownish  colour.  Leaves  closely  imbricated, 
broadly  ovate,  bidentate  at  the  apex,  crenulate  at  the  margins. 

Harrington,  Irish  Crypt,  in  Transactions  Bot.  Soc.  Edinb.,  vol.  7, 
p.  3,  tab.  1,  fig.  5  (1863);  Gottsche  et  Rabenhor.  Hep.  Europ. 
exsic.  n.  478.  Jungcrmannia  concinnata,  Taylor,  in  Fl.  Hib.  2, 
p.  59. 

Hab.  Frequent  on  the  higher  mountains  in  Ireland,  and  in  some  few 
instances  descending  to  sea  level.  Dr.  Carrington  refers  all  the 
Irish  localities  for  Jung,  concinnata  to  this  plant ;  he  considers 
the  true  Gymnom.  concinnatum,  Corda,  has  not  yet  been  observed 
in  Ireland.  After  due  examination  of  my  own  specimens,  and 
some  others  collected  in  Ireland,  I  feel  bound  to  corroborate  Dr. 
Carrington ;  they  are  all  referrible  to  G.  crenulatum,  Gottsche. 

Sub-tribe  7.  Achobolbk^. 
AcBOBOLsrs. 

Acrobolbus,  Nees,  in  G.  L.  et  N.  Synop.  Hepat.  p.  5  (1844) ;  Caning, 
in  Brit.  Hepat.  p.  41  (1874).  Gymnanthe,  Taylor,  in  Lehm.  Fl. 
Nov.  PugiU.  8,  p.  1  (1844);  Cooke,  Brit.  Hepat.  p.  15,  n.  76,  f. 
114. 

^'Involucre terminal,  obovate,  seated  at  right  angles  with  the  stem, 
bulbous  and  rooting  on  the  ventral  aspect.  Colesule  wanting. 
Calyptra  attached  to  the  bulbous  base  of  the  receptacle,  sur- 
rounded by  and  concrete  with  the  entire  portion  of  the  involucre, 
and  bearing  around  the  apex  the  abortive  pistiUidia." — Carring- 
ton, in  British  Hcpaticae. 

AcroholhuB  Wthoni,  Nees.  Stems  creeping,  and  mostly  parasi- 
tical on  the  stems  of  larger  Hepatics,  such  as  Badula  and  Frul- 
lania.  Leaves  succubous,  roundish  or  obovate,  acutely  bifid 
half-way  or  more,  rarely  trilobate,  closely  placed  on  the  stem,  and 
rather  obliquely  inserted.  Amphigastria  wanting.  Fructification 
terminal. 


662  Pro&eedings  of  the  Eoyal  Iriah  Aoademy. 

DilAiia,  Dnmort.  Comm.  Bot.  p.  114  (1822).  Diplomitiion,  Gorda, 
in  Opiz,  Naturalient.  p.  653  (1829).  DiplolsnA,  Dumoit.  8ylL 
Jong.  p.  82  (1831).  Blyttia,  Endl.  Oen.  FL  p.  13S9  (1840). 
Bteetzia,  Lehm.  PL  Preiss.  2,  p.  129  (1846).  Moerckia,  Gottfiche, 
in  Rabenhor.  Hep.  Eur.  ezsic.  n.  295  (1865).  PallaTiciniay  Cair. 
Gray's  Arr.  of  Hepat,  Trans.  Bot.  Soc.  Edinb.  10,  p.*  S09 
(1869). 

Inrolncre  monophyllons,  laciniated^  cap-shaped.  Colesule  tabular, 
exserted,  frequently  cleft  at  side.  Capsule  4-Talyed,  coiiaoeouB, 
naked.     Elaters  seminude,  deciduous. 

PManiciniu  Sihemica  (Hook.),  B.  Gray.  Frond  dichotomons, 
ribbed,  1  to  3  inches  long,  prostrate,  forked,  margin  crisped, 
entire.  Colesule  arising  from  upper  sniface  of  the  frond,  double, 
exterior  Ycry  short,  laciniated,  interior  much  exaerted,  oTate- 
oblong,  subplicate. 

Jungermannia  Hibemica,  Hook.  Brit.  Jung.  t.  78,  et  suppl.  t.  4 ;  suppl. 
to  Smith's  Engl.  Bot.  2,  Ub.  2750,  excl.  lower  half  of  plate. 
Dilena  Hibemica,  Dumort.  Comm.  Bot.  p.  114;  Hepat.  Europ. 
p.  137.  Diplolffina  Lyelli,  var.  y.  Hibemica,  Nees,  Europ.  Le> 
berm.  3,  p.  345.  Blyttia  Lyellii,  var.  y.  Hibemica,  G.  L.  et  N. 
Bynop.  Hep.  p.  475.  Moerdkia  Hibemica,  Gottsche,  in  Babenh. 
Hep.  Eur.  exsic.  n.  295,  334  et  335. 

Hab.  On  damp  sandy  ground,  among  the  sand-hills  near  the  sea, 
where  wat^r  has  stood  during  the  winter.  Between  Malahide 
and  Fortrane,  Co.  Dublin,  and  at  the  North  Bull.  Very  sparingly 
in  both  places,  and  seldom  fraiting. 

PdUwfieinia  Lyellii  (Hook.),  B.  Gr.  Frond  oblong-linear,  snb- 
dichotomous,  nerved,  crenated  or  subserrated  at  margin.  Peri- 
chaetium  fimbriated.  Colesule  cylindrical,  double,  rising  from 
the  nerve  on  upper  side  of  frond,  the  outer  shortest/  notched  at 
the  margin,  inner  slightly  toothed  at  mouth,  and  torn  on  one 
side. 

Jungermannia  Lyellii,  Hook.  Brit.  Jung.  t.  77;  Lindenb.  Synop.  Hepat 
p.  96 ;  Ekart,  Synop.  Jung.  p.  68, 1. 10,  fig.  87.  Dilsna  Lyellii, 
Dumort.  Comm.  Bot.  p.  114  (1822) ;  Rev.  Jung.  p.  25  ;  Hepat. 
Europ.  p.  137.  Diplomitrion  Lyellii,  Corda,  in  Opiz,  Natural, 
p.  654.  Blyttia  Lyellii,  G.  L.  et  N.  Synop.  Hep.  p.  475 ;  Ra- 
benhor. Hep.  Europ.  n.  121.  Hollia  LvelQi,  Sdilivant,  Musd 
Alleghanienses,  p.  66,  n.  281.  Steetzia  LyeUii,  Lehman,  Plant. 
Preiss.  2,  p.  129 ;  G.  L.  et  N.  Synop.  Hepat.  p.  785. 

Hab.  Boggy  spots  among  Sphagnum.  Bare.  Near  Bantry,  Cork,  Hiss 
Hutchins.  Lough  Bray,  Wicklow,  Dr.  Taylor.  Maghanabo  glen, 
near  Fermoyle;  Castlegregory,  and  by  the  lakes  between 
Maghanabo  Glen  and  Connor  Hill,  Co.  Kerry. 


MooKE — On  Irish  Sepatica.  663 

PSTALOPHTLLUH,  Gottsche. 

Codonia  {proparte\  Dumoit.  Comm.  Bot.  p.  Ill  (1822).  Diplolsena, 
spv  Nees,  Eur.  Leberm.  3,  p.  352  (1838).  Petalophylli  sp. 
Gottsche,  Syn.  Hep.  p.  471  (1846). 

Involucre  connate  witli  tlie  colesule.  Colesule  quadrato-campanulate, 
mouth  infundibulif orm,  undulate,  Bubdentate.  Capsule  coriaceous, 
univalved,  ultimately  cleft  into  4  irregular  segments. — ^Du- 
mortier. 

Fetdlophyllum  Ralfm  (Gottsche),  Wilson.  Frond  spreading  horizon- 
tally, broadly  obovate,  bluntly  forked  at  apex,  lamellated  and 
rayed.  Colesule  funnel-shaped,  broad,  and  toothed.  "  Capsule 
spherical,  bursting  irregularly." 

Jungermannia  Ealfsii,  Wilson,  in  suppl.  to  Engl.  Bot.  4,  tab.  2874. 
Diplolsena  Lyellii,  var.  8.  lamellata,  Nees,  Europ.  Leber.  3, 
p.  345.  Petalophyllum  Ralfisii,  N.  G.  in  Lehm.  Pugill.  8,  p.  30 ; 
G.  L.  et  N.  Syn.  Hep.  p.  472  ;  Cooke,  Brit.  Jung.  p.  22,  fig.  167. 
Codonia  Ralfsii,  Dumort.  Hepat.  Europ.  p.  16,  tab.  1,  fig.  2. 
Petalophyllum  lamellatum,  Lindberg,  Manipulus  Muse,  secund. 
p.  390. 

Hab.  On  damp  sandy  ground  near  the  sea.  Malahide  sands,  and  at 
North  Bidl  sands,  both  near  Dublin.  Not  hitherto  observed  else- 
where in  Ireland. 

Blasia,  Micheli. 

Bliisia,  Mich.  Nov.  PL  Gen.  p.  14  (1729);  Linn.  Fl.  Suec.  ed.  1, 
p.  933 ;  ed.  2,  p.  405  (1745) ;  et  Sp.  PI.  p.  1605  (1753). 
Jungermannia,  Hook.  Brit.  Jung.  tt.  82-84  (1816). 

Frond  nerved.  Perichaetium  pitcher-shaped,  attached  to  the  apex  of 
the  frond.  Colesule  within  the  perichsetium.  Capsule  quadri- 
valved.    Elaters  geminate.     Inflorescence  dicecious. 

Blofiia  pusiUa  (JAim.)  Frond  oblong,  divided  at  the  apex  palmately 
or  dichotomously,  nerve  broad,  with  scattered  dentate  scales  be- 
neath. Colesule  rising  from  the  upper  side  of  the  frond  near  the 
point. 

Blasia  pusilla,  Linn.  Sp.  PL  1605;  Web.  et  Mohr,  Crypt.  Germ, 
p.  437  ;  Hoffm.  Germ.  2,  p.  22,  tab.  3 ;  Dumort.  Hepat.  Europ. 
p.  135.  Jungermannia  Blasia,  Hook.  Brit.  Jung.  t.  82-84; 
Ekart,  Synop.  tab.  11,  fig.  94,  et  tab.  13,  fig.  114;  Taylor,  in 
Fl.  Hib.  p.  56. 

Hab.  On  sandy  moist  banks  by  the  sides  of  streams,  &c.  Fruiting  in 
March  at  Castle  Kelly  glen,  Dublin,  Dr.  Taylor.  Moist  banks 
near  the  Wooden  Bridge,  Wicklow;  at  the  base  of  Brandon 
Mountain,  Kerry;  but  not  very  common  anywhere  in  Ireland. 


664  Proeeedingi  of  the  Royal  Irish  Academy. 

Pellia,  Baddi. 

Jungormaimia,  Linn.  Fl.  Suec.  1  ed.,  p.  399,  n.  930  (1745),  et  8p.  PI.  T 
ed.  2,  p.  1135,  n.  23  (1753) ;  Hook.  Brit.  Jung.  tab.  47  (1816,. 
Pellia,  Eaddi  in  Att.  Soc.  Modena,  18,  p.  49  (1818).  Papa, 
B.  Gray,  in  Gray's  Nat.  Arr.  Brit.  PL  1,  p.  686,  n.  12  (1821). 
Scopulina,  Dumort.  Comm.  Bot.  p.  115  (1823). 

Perichietiam  cup-shaped,  mouth  lacerated.  Colesule  wanting.  Cap- 
sule quadriyalved,  exscrted  on  a  succulent  smooth  footstalk. 
Elaters  persistent,  with  two  spires. 

1.  PeUia  epiphyUa  (Bill.  L.),  Raddi.    Paroecious.  Frond  oblong,  lobed 

and  sinuate,  thick  and  somewhat  fleshy  nerved  or  much  thickened 
in  the  centre.  Fruit  from  the  upper  surface  of  the  frond  towarda 
the  extremity.  Pcrichaetium  anteriorly  formed  of  the  frond, 
mouth  lacerated  or  dentate.     Capsule  exserted. 

Jungennannia  epiphylla,  Linn.  Sp.  PI.  1  ed.,  2,  p.  1135;  Hook.  Brit. 
Jung.  t.  47,  figs.  1,  4,  8,  1, 17;  Engl.  Bot.  tab.  771 ;  Fl.  Ban.  2, 
fasc.  6,  tab.  359 ;  lindenb.  Synop.  Hep.  p.  97 ;  Ekart,  Synop. 
Jung.  p.  63,  t.  7,  fig.  52  ;  Taylor,  m  FL  Hib.  p.  56.  Pellia  Fab- 
broniana,  Baddi  in  Att.  Soc.  8c.  Modena,  18,  p.  49 ;  Corda,  in 
Opiz,  Natural,  p.  654  ;  Bumort.  Bev.  Jung.  p.  27,  et  Hep.  Enrop. 
p.  145;  G.  L.  et  N.  Synop.  Hcpat.  p.  488;  Babenhor.  Hep. 
Europ.  exsic.  n.  31,  119,  274,  357. 

Hab.  On  moist  clay  banks  and  wet  ground.  Very  abundant  in  all 
parts  of  Ireland. 

2.  PeUia  ealyeina  (Nees),  Taylor.     BicBcious.    Frond  linear-oblong, 

dichotomously  divided,  concave,  raised,  and  sinuate  at  the  edges, 
midrib  well-defined.  Fruit  rising  from  the  upper  surface  of  the 
frond  over  the  midrib.  Perichastium  cup-shaped,  subplicate, 
fringed  at  the  mouth.  Calyptra  inclosed.  Antheridia  imbedded 
in  the  midrib  on  the  upper  surface  of  the  frond. 

Jungermannia  epiphylla,  var.  y.  furcigera,  Hook.  Brit.  Jung.  t.  47, 
f.  18,  et  2,  3,  9,  10-12.  Jungermannia  ealyeina,  Taylor,  in  Fl. 
Hib.  2,  p.  55 ;  EngL  Bot.  suppL  t.  2875.  Pellia  endivifolia, 
Pluk.,  Bicks.,  Lindb.  Pellia  ealyeina,  Nees,  Europ.  Leber.  3, 
p.  386 ;  G.  L.  et  N.  Synop.  Hepat.  p.  490 ;  Babenhor.  Hepat. 
Europ.  exsic.  n.  181,  242,  339;  Cooke,  Brit.  Jung.  p.  23, 
fig.  172 ;  Cogn.  Hepat.  Belg.  p.  47. 

Hab.  Shady  moist  places,  sometimes  altogether  immersed  in  water. 
Bunkerron,  Kerry,  Br.  Taylor.  Tore  Cascade  and  Cromaglown, 
Br.  Carrington.  Altadore  glen,  and  Lough  Bray,  Wicklow ;  very- 
large  and  fine  at  Glencar,  Co.  Sligo ;  Glenballyemon,  Antmn. 


Moore — On  Irish  Hepatkce.  665 

Sub-tribe  9.    Metzgeriks. 

Meizgeria,  Raddi.* 

Jungennannia,  L.  Fl.  Suec,  1  ed.,  p.  338,  n.  928  (1745),  et  Sp. 
PI.  1  ed.,  2,  p.  1136,  n.  26  (1753)  ;  Hook.  Brit.  Jung.,  tt.  45, 
46  (1816).  Metzgeria,  Raddi,  in  Att.  Soc.  Modena,  18,  p.  45 
(1818);  Lindb.  apud  Soc.  F.  FLFenn.  (1874);  sect.  1,  G.  L.  et 
K.  Synop.  Hep.,  p.  502  (1846).  Hervera,  B.  Gr.  in  Gray's  Nat. 
Air.  Brit.  PL  1,  p.  685,  n.  11  (1821).  Fasciola,  Dumort.  Comm. 
Bot.,  p.  114  (1828).  Echinogyna,  Dumort.  Syll.  Jung.  Eur., 
p.  83,  n.  22  (1831).  Echinomitrium,  Hiiben.  Hep.  Germ. 
p.  46,  n.  16(1834). 

Fronds  ribbed,  flat,  dichotomous  or  subpalmately  branched.  Fruit 
rising  from  the  lower  surface  on  the  midrib.  Involucral  bract 
two-Hpped,  ventricose.  Capsules  elevated  on  long  stalks,  quadri- 
valved.  Elaters  persistent  to  the  points  of  the  valves,  one-spired. 
Antheridia  from  the  midrib  of  under  side  of  frond. 

1.  Metftgeria.  furcata  (Linn.),   Dumort.      Dioecious.     Fronds  linear, 

flat,  dichotomously  forked,  smooth  on  upper  surface,  the  maigin 
and  costa  beneath  subpilose.  Fruit  rising  from  the  midrib  on 
the  under  side.     Calyptra  setulose. 

Jungennannia  furcata,  Linn.  Sp.  PI.  1602  ;  Hook.  Brit.  Jung.,  tt.  55 
et  56;  Lindenb.  Synop.  Hepat.,  p.  94;^  Engl.  Bot.,  t.  1632. 
Metzgeria  glabra,  Eaddi,  Jung.  Etr.  in  Mem.  Modena,  18,  p.  43, 
t.  7,  fig.  1.  Metzgeria  furcata,  Dumort.  Rev.  Jung.,  p.  26  ; 
Hepat.  Europ.,  p.  139;  G.  L.  et  N.  Synop.  Hep.,  p.  302; 
Eabenhor.  Hep.  Europ.  exsic.  31,  179,  357. 

Hab.  On  trunks  of  trees  chiefly,  but  also  on  moist  banks  and  rocks. 
Var.  3.  aruginoaa.  Frequent  on  trunks  of  trees. 

2.  Metzgeria  pubeseens,  Raddi.     Frond  linear,  subdichotomous,  glau- 

cous green,  nerved,  pubescent  on  both  surfaces.  Antheridia  on 
the  lower  surface  of  the  frond,  attached  to  the  midrib. 

Jungennannia  pubescens,  Schrank.  Prim.  Fl.  Salisb.,  p.  231 ;  Hook. 
Brit.  Jung.,  t.  73 ;  Lindenb.  Synop.  Hepat.,  p.  95 ;  Ekart, 
Synop.  Jung.,  p.  67,  t.  3,  fig.  19.  Metzgeria  pubescens,  Raddi, 
Jung.  Etrus.  Mem.  Mod.  18,  p.  46;  G.  L.  et  N.  Synop.  Hepat., 
p.  504 ;  Rabenhor.  Hepat.  Europ.  exsic,  n.  84 ;  Dumort.  Hepat. 
Europ.,  p.  140. 

Hab.  On  moist  rocky  banks,  and  in  woods.  Mountains  near  Belfast, 
Mr.  Templeton,  in  Fl.  Hib.  On  limestone  rocks  between  Lumo 
and  Glenarm,  and  at  Sillaghbraes,  near  Lame,  Antrim,  1837. 
Again  at  same  place,  M.  S.  A.  Stewart,  March,  1876.  This  rare 
species  has  not  been  found  in  any  of  the  Irish  counties,  save  Co. 

*  Ab  a  sub-tribo  of  the  AnomogameB,  by  Lindberg. 


666  Proceedings  of  the  Royal  Irish  Academy. 

Antrim,  up  to  the  present  time :  good  specimens  from  thence  are 
in  the  herbarium  from  the  Ordnance  Survey,  at  the  College  of 
Science,  Dublin. 

^.  Mehfferia  linearis  (Sw.),  Lindb.,  Monogr.  n.  6.  Dioecious.  Stems 
robust,  much  elongated,  dichotomous,  of  equal  breadth  through- 
out, their  margins  much  reflezed,  nearly  meeting  so  as  to  make 
the  stems  appear  half  round  when  dry,  in  transverse  section 
sub-elliptic,  hairs  very  long,  in  twos  or  threes  together,  spreading 
widely,  and  arcuately  bent.     Fruit  (?) 

Jungermannia  furcata,  var.  fi.  elongata,  Hook.  Brit.  Jung.  tab.  56, 
fig.  2;  Ekart,  Syn.  Jung.  tab.  1,  figs.  1,  2,  p.  67.  J.  furcata, 
p,  maxima,  Weber,  Spicil.  Fl.  Goett.  p.  160. 

Hab.  In  moist  situations  on  the  ground.  I  collected  this  remark- 
able plant  in  some  quantity  in  a  small  stream  which  empties 
itself  into  the  deep  lake  at  the  top  of  the  glen  leading  up  to  the 
highest  point  of  Brandon  Mountain,  in  1865.  The  plant  was 
altogether  in  the  water,  and  the  stems  were  from  4  to  5  inches  long. 
Believing  it  to  be  quite  distinct  from  M.  furcata,  I  sent  it  to 
some  of  our  best  authorities,  who  thought  otherwise.  It  there- 
fore remained  for  Dr.  Lindberg  to  establish  the  species,  who  also 
collected  it  in  1873,  at  Cromaglaun,  &c.  He  states  in  his  obser- 
vations on  the  Hepatic®  collected  in  Ireland,  1873,  that  he 
possesses  specimens  of  the  same  plant  from  North  America,  the 
islands  of  Jamaica  and  Guadeloupe;  Sikkim,  Himalaya;  New 
Zealand;  and  from  Sutherland  shire  in  Scotland.  The  Irish 
specimens  have  neither  male  nor  female  fruit. 

4.  Metzgeria  conjugata  (Dill.),  Lindb.,  Monogr.  n.  7.  Autoecious. — 
**  Stems  robust,  not  much  elongated,  more  or  less  dichotomous, 
irregularly  pinnated  or  decomposite  linear,  but  narrower  in  some 
parts  than  in  others,  in  transverse  section  semilunar,  margins 
remote,  hairs  longish,  singly  or  often  in  pairs  on  margin,  and 
divergent." 

Bisch.  Handb.  Bot.  Term.  tab.  56,  fig.  2756 ;  Dill.  Hist.Musc.  tab.  74, 
fig.  45;  D.  et  E.  Hedw.  Theor.  Gen.  1  ed.,  tab.  19,  figs.  9,  99  et 
100,  tab.  20,  figs.  101-109 ;  2  ed.,  tab.  21,  figs.  4,  5,  tab.  22,  figs. 
1-9;  Sturm,  Deutschl.  Fl.  2,  fasc.  26,  27,  tab.  38 ;  Aust.  Hep.  Bor.- 
Am.  n.  117  (inflor.);  Funck.  Crypt.  Gew.  Ficht.fasc.  21,  n.  438; 
Gottsche  et  Rabenhor.  Hep.  Eur.  exsic.  n.  274-6. 

Hab.  Glena  and  Tore  Cascade,  on  the  bark  of  old  trees.  O'Sullivan's 
Cascade,  Killamey,  among  Hookeria  laetevirens.  Dr.  Lindberg, 
1873.  Not  being  ac(^uainted  with  this  plant,  the  description  and 
quotations  of  authorities  are  after  Lindberg,  in  ''Acta  Societ. 
Scientiarum  Fennicse,  x."  Judging  from  the  -figures  in  Dil- 
lenius,  it  would  be  readily  passed  over  for  a  state  of  Riccardia ; 
so  also  from  the  the  smaller  fig.  in  Hedwig's  Theoria,  No.  99,  but 
the  magnified  fig..  No.  100,  shows  the  plant  to  be  a  true  Metz- 


Moore — On  Irish  Sepaticce.  667 

geria.  In  €h>ttsche  and  Eabenhor.  Hep.  Eur.  ezfiic,  n.  274, 
Metzgeria  furcata,  var.  fi,  nuda,  affords  a  good  example  of  thi» 
plant.  The  paucity  of  hairs,  and  more  homy  substance  of  tho 
stems,  distinguish  it  from  any  of  the  normal  states  of  M.  furcata; 
but  the  chief  distinguishing  character  seems  to  be  the  autoecious 
inflorescence,  which,  as  Lindberg  observes,  is  remarkable  in  a 
genus  where  all  the  other  species  of  it  are  dioecious.* 

BiccABDiA,  Bennett,  Gray.f 

Jungermannia,  L.  Fl.  Suec.  1  ed.,  p.  399,  n.  929  (1746),  et  Sp.  PI., 
1  ed.,  2,  p.  1136,  n.  24  et  25  (1741);  Hook.  Brit.  Jung.  (1816). 
Boemeria,  Baddi,  in  Att.  Soc.  Modena,  18,  p.  46  (1818).  Biccardia, 
B.  Gr.  in  Gray's  Nat.  Arr.  Brit.  PI.  1,  p.  683,  n.  9,  excl.  sp.  n.  a 
(1821);  Carruth.  in  Seem.  Joum.  Bot.  3,  p.  802  (1865). 
Aneura,  Dum.  Comm.  Bot.  p.  115  (1823);  Syll.  Jung.  Eur,, 
p.  85  (1831).  Metzgeria,  Corda,  in  Opiz,  Beitr.,  1,  p.  654,  n.  12 
(1829). 

Erond  fleshy,  pinnatifid  or  sinuate,  partially  nerved  or  without 
nerve.  Fruit  rising  from  the  margin  of  the  frond,  under- 
neath. Involucre  short,  cupuliform.  Golesule  wanting.  Calyptra 
exserted,  smooth,  fleshy.  Capsule  quadrivalved.  Elaters  with  a 
broad  single  spire,  attached  to  the  tips  of  the  valves  of  the  cap- 
sule.   Antheridia  in  marginal  receptacles. 

1.  Rieemrdia  multifida  (Dill.,  Linn.),  Gr.  Autcecious.  Frond  linear^ 
multifld,  nerveless,  fleshy.  Fruit  marginal.  Calyptra  exserted, 
tuberculated. 

Jungermannia  multiflda,  Linn.  Sp.  PI.  p.  1602;  Engl.  Bot.  t.  186; 
Hook.  Brit.  Junger.  t.  45,  excl.  yar.  p. ;  Lindenb.  Synop.  Hepat., 
p.  98;  Aueura  multifida,  Dumort.  Comm.  Bot.,  p.  115;  Syll. 
Jung.,  p.  85 ;  Hepat.  Europ.,  p.  141 ;  Nees,  Europ.  Leberm.,  3, 

6449 ;  G.  L.  et  N.  Synop.  Hepat.,  p.  496 ;  De  Notaris,  Prim, 
epat.  Ital.,  p.  46 ;  Babenhor.  Hepat.  Europ.  exsic.  n.  463. 
Hab.  On  wet  spots,  where  water  has  stood  during  winter,  and  among 
wet  grass  and  heaths.  Yery  common  in  Ireland.  Varieties  of 
this  variable  plant  are  of  frequent  occurrence.  Variety  pinnati- 
fida,  Dumort.  Syll.  Jung.  =  Aneura  pinnatifida,  Dumori;.  Bev. 
Jung.  p.  26 ;  Hepat.  Europ.,  p.  142  (J.  sinuata,  Dicks.  [?J),  are 
found  at  Killamey  ;  Galtymore,  Tipperary ;  and  at  Luggielaw : 
var,  submersa,  on  wet  bogs  near  MuUingar,  Westmea^.     This 

*  Although  this  genufi  and  the  following  are  placed  by  Lindberg  in  divisionn, 
according  to  the  principles  and  characters  which  mark  the  respective  sections 
of  his  arrangement,  they  are  thereby  placed  among  plants  they  have  otherwise  littla 
relationship  with.  I  miye,  therefore,  inserted  them  among  those  of  a  more  con- 
genial nature,  where  they  have  been  long  and  naturally  placed.  In  doing  so,  I 
nave  at  the  same  time  indicated  the  position  given  them  by  Dr.  Lindberg. 

t  By  Lindberg,  as  a  sub-tribe  in  the  sub-section  f,  Opisthogamie. 


668  Proceedings  of  the  Royal  Irish  Academy. 

latter  yariety  grows  in  the  water,  in  close  balls  of  fronds,  three 
or  four  inches  in  diameter.  Variety  ambrosioides,  Kees,  Killar- 
ney,  Dr.  Carring;ton. 

2.  Rieeardia  palmata  (Hedw.)*  Camith.,  landb.    Dioecious.    Stems 

shorty  rather  crowded,  and  free  at  apex,  palmately  cut,  segmentB 
linear,  and  frequently  tapering  to  a  point  or  slightly  emarginate. 
Involucral  bracts  small.    Calyptra  small,  and  densely  yermcose. 

Jungermannia  palmata,  Hedw.  Theor.  Gen.  1  ed.,  p.  87,  tab.  18,  figs. 
93,  95 ;  et  tab.  19,  figs.  96-98  ;  Schmid.  Icon.  PL  3,  p.  213-216 
(ezcl.  synon.);  Ekart,  Synop.  Germ.,  tab.  13,  fig.  115  ;  Fl.  Dan.  5. 
fasc.  15,  tab.  898,  fig.  3;  Sturm,  Deutschl.  Fl.  2,  faac.  26  et  27, 
tab.  35.  Aneura  palmata,  Dumort.  Comm.  Bot.  p.  1 15;  Syll.  Jmig., 
p.  86,  et  Hepat.  Europ.,  p.  143 ;  lindberg,  Manipulus  Musd. 
secundus,  Helsingfors  (1874). 

}Iab.  On  the  putrid  trunks  of  old  trees,  at  Cromaglaun,  Xeiry; 
Altadore  Glen,  Wicklow.  Tore  Mountain,  and  Eagle's  Nest,  El- 
lamey,  Dr.  Carrington.  Abundant  on  a  small  idand  off  Bally- 
nakill  Harbour,  Co.  Galway. 

3.  Rieeardia  pinyuii(Lijm,\'B.QT.     Dioecious.     Fronds  procumbent, 

one  or  two  inches  long,  fleshy,  linear-oblong,  simple  or  slightly 

lobcd,  margins  sinuate.    Fruit  rising  from  under  the  margin. 

Calyptra  hemispherical,  smooth.  Capsule  brownish  and  fuirowed. 
Jungermannia  pinguis,  lann.   Sp.  Plant.,  p.  1602;  8chmidel,  Icon. 

p.  136,  tab.  35 ;  Engl.  Bot.,  t.  185 ;  Hook.  Brit.  Jung.,  t.  46; 

Ekart,  Synop.  Jung.,  p.  62,  tab.  7,  fig.  51 ;  Taylor,  in  Fl.  Hib., 

p.  57.     Boemeria  pinguis,  Baddi,  in  Mem.  Modena,  18,  p.  46. 

Aneura  pinguis,  Dumort.  Comm.  Bot.,  p.  115 ;  Syll.  Jung.,  p.  86, 

tab.  2;  et  Hepat.  Europ.,  p.  143 ;  Nees,  Europ.  Leberm.,  3,  p.  427; 

G.  L.  et  K  Synop.  Hep.,  p.  493 ;  Cooke,  Brit.  Jung.,  p.  28,  fig. 

174;  Eabenhor.  Hep.  Europ.  ezsic.  n.  41,  103,  436. 
Hab.    Damp  ravines,  sides  of  rivulets,  and  among  wet  heath.    Not 

unfrcquent  in  the  Killamey  district,  Kerry.    On  wet  sand  at  Ma- 

lahide,  Dublin ;  and  at  Lough  Bray,  Wicklow. 

4.  A.  latifrons,  Lindberg.     "  Autoica,  rarissime  paroica,  major,  pel- 

lucid; caulis  longus  et  latus,  dissolutus  in  ramos  latos,  cervicorni- 
formes,  plus  minusve  oblongo-cuneatos,  obtusissimos  et  emargina- 
tos,  plano-convexos,  vix  umquam  gonidia  antice  gerentes ;  cel- 
lulse  magnse,  oblongo-rhombese,  baud  incrassatae;  bractesdperi- 
chffitiates  paucsebus ;  calyptra  magna  et  minus  verrucosa ;  androe- 
cium  auguste  oblongum,  fere  semper  ad  latus  perichsdtii  affizum." 
— Lindberg. 
Jungermannia  multifida,  Schmid.  Icon.  Fl.  3,  pp.  213-216,  excl. 
synon.  et  pp.  (1797);  Hook.  Brit.  Jung.  p.  19,  n.  75,  pp.  (1816). 
Aneura  palmata,  a  major,  Nees,  Europ.  Leber.  3,  p.  459  ;  0. 1- 
et  N.  Synop.  Hepat.  p.  498 ;  Gottsche,  in  Fl.  Dan.  16,  fasc.  4,  p.  21, 


Moore — On  Irish  SepaticcB.  669  ' 

n.  2815.  A.  latifronsi  Lindb.  apud  Soc.  pro.  P.  et  El.  Fenn. 
(1873),  etin  Bot.  Not.  p.  62  (1873).  Delin. :— Hook.  Brit.  Jung., 
tab.  45,  figs.  4,  7  et  12 ;  Ekart,  Synop.  Germ.  tab.  7,  fig.  50,  1,  2, 
et4;  Fl.  Dan.  IG.fasc.  47,  t.  2815,  fig.  2. 

Hab.  On  moist  toify  banks,  and  decaying  stems  of  trees.  EiUamey, 
Br.  Lindberg. 

I  Lave  copied  closely  Dr.  Lindberg' s  description  and  synonymy 
(Kepat.  in  Hiber.  Lectse,  p.  513)  of  this  species,  which  I  am  not 
well  acquainted  with,  though  Dr.  Lindberg  pointed  it  out  to  me, 
growing  near  O' Sullivan's  Cascade,  Killamey,  in  1873.  It  is 
the  plant  figured  by  Hooker  for  Jung,  multifida,  in  Brit.  Jung. 
{pro  parte)  f  and  what  Dr.  Taylor  and  others,  including  myself, 
have  long  considered  that  species.  Hooker's  var.  ^.,  which 
forms  part  of  tab.  45,  in  Brit.  Jung.,  is  described  as  a  species  by 
Dumortier,  in  Hepat.  Europ.,  viz.,  Aneura  sinuata,  p.  142. 
Although  these  are  conspicuous  plants,  it  is  exceedingly  difficult 
to  define  their  limits  as  species  or  varieties. 

B.    CLEISTOCABPiB. 

Tribe  1.  Sph-srocabpe^. 

Sph.£bocaspus,  Micheli. 

Sphffirocarpus,  Mich.  Nov.  PI.  Gen.  4,  t.  3  (1729);  Dumort.  Comm. 
Bot.,  p.  78  (1822).  Targiona  sphserocarpus,  Dicks.  Fasc.  1,  p. 
8,  n.  2(1785). 

Involucre  sessile,  seated  on  the  frond  near  its  base,  pear-shaped  and 
perforated  at  the  apex,  without  bracts,  and  one-fruited.  Capsule 
closely  invested  by  the  isalyptra.  Antheridia  on  separate  fronds, 
in  f  olliculose  bodies. 

JSpharocarpu8  terrestris,  Sm.  Frond  roundish,  in  clusters,  horizon- 
tally attached  to  the  ground  by  short  radicles,  oblong,  waved, 
their  disk  covered  with  tufts  of  the  fructification. 

SphaBrocarpus  terrestris,  Sm.  Engl.  Bot.  t.  299 ;  Lindenb.  Synop.  Hep. 
p.  Ill ;  Nees,  Eur.  Leber.  4,  p.  365.  Sphaerocarpus  Michelii,  Bel- 
lardi.  Act.  Tur.,  5,  p.  246 ;  SuUivant's  Musciand  Hepaticse  of  the 
TJ.  S.  p.  84.  t.  6.  Sphaerocarpus  lagenarius,  Dumort.  Comm. 
Bot.  78. 

Hab.  On  the  earth,  in  fields  consisting  of  strong  clay  land  which  arc 
moist  in  winter.  On  a  wet  clay  bank  at  CoUin  Glen,  near  Bel- 
fast, Mr.  David  Orr.  I  have  ne^er  seen  any  Irish  specimens  of 
this  plant,  nor  have  I  heard  of  it  having  been  observed  by  any 
other  person  than  Mr.  Orr  in  Ireland. 


670  Proceedings  of  the  RoycU  Irish  Academy, 

SscnOK  III.      AlTTHOCEEOTACEJE. 

Tribe  2.  Ain^oGEBOXEJE. 
Akxhocebos,  Micheli. 

Anthoceros,  Mich.  Nov.  Gen.  p.  10,  tab.  7  (1729).  Corypta,  Neck. 
Elem.  Bot.  3,  p.  344,  n.  1768  (1790).  Carpoceros,  Dum.  Comm. 
Bot.  p.  76  (1823). 

Colesule  tubular.  Capsule  filiform,  bivalved,  with  a  free  central  pla- 
centa, exserted.  Elaters  articulated,  flexuose,  without  spores  or 
spores  imperfect.  Antheridia  dorsal,  sessile  in  a  cup-shaped 
involucre. 

1.  Anthoceros  punctatus,  lAim.    Paroecious.    Frond  orbicular,  radiate^ 

lacerate,  with  immersed  gemm®  in  its  substance,  margins  pli- 
cate, crenate,  papillose  on  the  surface,  nerveless.  Colesule  erect, 
cylindrical,  mouth  truncate. 

Anthoceros  punctatus,  linn.  8p.  PL  1606 ;  Lindenb.  Hepat.  Eur., 
p.  113;  Sm.  Engl.  Bot.,  t.  1537;  Nees,  Eur.  Leberm.  4,  p.  338 ; 
G.-L.  et  N.  Synop.  Hepat.  683;  Eabenhor.  Hepat.  Eur.  exsic. 
n.  64,  462,  484. 

Hab.  Wet  places,  by  the  sides  of  streams,  and  on  ditch  banks. 
Glendoon,  Co.  Antrim ;  Kelly's  Glen,  Co.  Dublin.  Sugar  Loaf 
Mountain,  Co.  of  Wicklow,  Dr.  E.  Perceval  Wright ;  but  not  com- 
mon in  the  northern  or  eastern  counties  of  Ireland.  Frequent 
in  the  counties  of  Kerry  and  Cork. 

This  remarkable  genus  among  the  HepaticsB  is  easily  recognised  when 
found  in  fruit,  but  when  not  in  a  fruiting  state,  the  species  may 
readily  be  passed  over  for  states  of  PelHa.  From  most  of  the 
Marchantiacese  the  fronds  may  be  distinguished  with  the  aid  of  a 
lens,  by  the  absence  of  true  pores  on  their  surface. 

2.  Anthoceros  kevis  (Dill),  L.     Dioecious,  (Lindb.)  Frond  deep  green, 

smooth  on  surface,  nerveless,  subradiate.  Colesule  broad,  sca- 
rious. 

Anthoceros  Isevis,  Linn.  8p.  PL  1606  ;  Lindenb.  Hepat.  Eur.  p.  112  ; 
Nees,  Europ.  Leber,  4,  p.  329  ;  G.  L.  etN.  Synop.  Hepat.  p.  586 ; 
Eabenhor.  Hep.  Eur.  exsic.  n.  64,  462,  484. 

Hab.  On  clay  banks,  &c.  On  a  wet  clay  bank,  by  the  roadside  lead- 
ing from  Dingle  to  Ventry,  left-hand  side  of  road,  about  a  mile 
and  a-half  from  Ventry.  This  species  was  collected  in  consi- 
derable abundance  by  Dr.  Lindberg  and  myself,  in  July,  1873, 
when  it  was  in  fine  fruit.  I  am  not  aware  of  it  having  been 
observed  elsewhere  in  Ireland  up  to  the  present  time. 


Moore — On  Irish  Hepaticm.  671 

List  op  Works,  Papers,  etc.,  relating  to  the  Hepaticjb 

OP  Ireland. 
Thomas  Tatlob,  M.  D.  :— 

"  In  Flora  Hibernica.  Part  2.  HepaticaB(1836)."  Eighty-two 
specieB  are  described  and  enumerated. 

"  Descriptions  of  Jungermannia  nlicina  (Taylor)  and  longer* 
mannia  Lyoni  (Taylor)."  Transactions  of  the  Edinburgh  Bo- 
tanical Society.  Vol.  1,  p.  116  (1841).  Adds  J.  Lyoni 
(Taylor)  to  the  Irish  list. 

^'  On  two  new  species  of  Jungennannia,  and  another  new  to 
Britain."  Transactions  of  the  Edinburgh  Botanical  Society. 
Vol.  1,  p.  179  (1843-4).     Adds  J.  punctata,  Taylor. 

**  On  four  new  species  of  British  Jungermannia."  Transactions  of 
the  Edinburgh  Botanical  Society.  Vol.  2,  p.  43  (1843).  Adds 
Jungermannia  riparia,  Taylor;  J.  reclusa,  Taylor;  J.  fragi- 
folia,  Taylor;  J.  germana,  Taylor. 

''  Contributions  to  British  Jungermannia."     Transactions  of  the 
Edinburgh  Botanical  Society.     Vol.  2,  p.  115  (1844).     Adds 
Jungermannia  nimbosa,  Taylor;  J.  curta,  Martins  ;   J.  Thuja, 
Dickson ;  J.  rivularis,  Nees ;  J.  aqmlegia,  Taylor. 
D.  MooBE,  Ph.  D.  :— 

''  Ordnance  Surrey  Collections  of  Counties  of  Derry  and  An- 
trim." Vol.  1.  Mosses  and  Hepaticee,  ezsicc.  (1834-8). 
Fifty-five  species. 

^'  Contributions  to  the  British  and  Irish  Musci  and  Hepaticas." 
Proceedings  of  Dublin  University  Zoological  and  Botanical  As- 
sociation. Vol.  2,  p.  80  (1868).  [Read  February  20th,  1861]. 
Adds  SarcoscyphuB  Funckii  (1837);  Scapania  subalpina,  var. 
p.  undulif olia ;  Aneura  palmata ;  Petalophyllum  Balf  sii,  Wil- 
son ;  and  a  new  habitat  for  J.  cuneif olia. 

"  Dublin  Natural  History  Society's  Proceedings."  Vol.  5,  p.  89 
(1866).  Adds  Scapania  undulata,  var.  A,  major,  Nees;  and 
some  new  habitats. 

Thomas  Powee,  M.  D.  : — 

''  Contributions  towards  the  Fauna  and  Flora  of  Cork.  Part  2. 
Botany  (1844)."     Fifty  species  of  Hepaticse  are  enumerated. 

B.  Caekiwotok,  M.  D.  : — 

"  Gleanings  among  the  Irish  Cryptogams."  Transactions  of  the 
Edinburgh  Botanical  Society.  Vol.  7,  p.  379  (1863).  Adds 
Jungermannia  obovata,  Nees ;  and,  gleaned  from  other  sources, 
Preissia  commutata,  Nees;  Fossombronia  angulosa,  Eaddi; 
Scapania  compacta,  Lindenb. ;  S.  irrigua,  Nees ;  J.  nana, 
Nees ;  J.  bicrenata,  Lindb. ;  Oymnanthe  Wilsoni,  Taylor ; 
Madotheca  laevigata,  Dumort. ;  and  Madotheca  rivularis,  Nees. 

K.  I.  A.  PBOC,  8SB.  II.,  VOL.  11.,  8CIBX0B.  8  E 


672  Proceedings  of  the  Rayai  Irish  Academy. 

8.  0.  LnrDBEEo : — 

''  Hepaticse  in  Hibemia  mense  Jolii,  1873,  lectse."  Acta  Sooie- 
tatis  Scientiarum  Fennicas,  x.  (1874).  Adds  Eiccia  sorocarpa, 
Bischoff ;  Lejeunea  patens,  Lindb. ;  Lejeunea  Moorei,  Lindb. ; 
Porella  pinnata,  Dill. ;  Metzgeria  linearis,  Sw. ;  Metzgeria 
conjagata,  Lindb. ;  Cephalozia  multiflora  (DiU.),  Hnds. ;  Gc- 
phalozia  elachista,  Jack. ;  Kantia  argnta,  Dill. ;  Eiccardia  lati- 
frons  (Schmid.),  Lindb. ;  Nardia  sphacelata,  Gies. ;  Scalia 
Hookeri  (Lyell),  Gray ;  Anthoceros  Itevis  (Dill.),  L. 


The  species  added  in  tbe  present  Beport  are  Ricciella  floitans, 
Al.  Braon,  Hook. ;  Eicdocarpus  natans,  Corda ;  Cephalozia  Francisu, 
Hook.  ;  Pedinophyllum  pyrenaicnm,  Spmce ;  Scapania  nliginosa, 
Dumort. ;  Scapania  ssquiloba,  Dnmort.  (vera);  Jnngermannia  Hom- 
schuchiana,  Nees ;  Jungermannia  capitata,  Hook. ;  Nardia  revolnta, 
Nees ;  Sphaerocarpus  terrestris,  Sm. ;  Lejeunea  flava,  Swartz. 

G.  M.  Cotter,  in  M.  F.  Cusack's  "  History  of  the  City  and  County 
of  Cork''  (1875),  enumerates  twenty-nine  HepaticsB  not  noticed  in 
Dr.  Power's  Hst  of  1844. 


ADDinOKS  Ain>  COBBECnOVS. 

Lejeunea  flavay  Swartz.  Stem  branched,  creeping.  Leaves  sub- 
imbricated,  oblong-ovate,  entire,  rounded  at  apex,  lobule  somewhat 
convolute.  Amphigastria  ovate-cordate,  much  smaller  than  the  leaves, 
acutely  bifid,  divisions  ovate-lanceolate.  Fruit  lateral  at  base  of 
branchlets.     Colesule  exserted,  pentagonal. — Gottsche,  Ic.  Lej.  vii. 

Junger.  flava,  Swartz,  Prodr.  Fl.  Ind.-Occ.  p.  144;  Fl.  Ind.-Occ. 
iii.  p.  1859;  Schwseger,  Prodr.  p.  16;  Web.  Prodr.  p.  29;  Spreng. 
S.  7.  4,  1,  p.  223,  n.  74;  Spruce,  in  Trimen's  Journal  of  Botany, 
new  series,  vol.  v.  1876,  p.  198. 

Hab.  KiUamey,*  J,  T.  Mackay. 

Dr.  Spruce  assures  us  that  a  fine  patch  of  this  plant,  gathered  at 
Killamey  by  the  late  Mr.  Mackay,  is  in  Sir  William  Hooker's  her- 
barium. Dr.  Lindberg  considers  tiiat  this  species  is  closely  allied  to 
his  new  species,  L.  Moorei.  E«ferring  to  the  latter,  he  states: 
'*  Very  probably  this  new  and  very  distinct  species  is  to  be  very  care- 
f uUy  compared  with  L.  flava,  Swartz ;  and  I  have  really  felt  doubt 
whether  the  two  are  different  from  each  other  ;  but  as  I  have 
not  seen  the  former  (L.  flava),  I  am  unable  to  decide"  (Lindb.  in 
•'  Acta  Societatis  Scientiarum  Fennic©,"  x.  p.  487).  I  am  myself  in 
a  similar  position  to  that  of  Dr.  Lindberg,  not  having  seen  plants  of 
L.  flava,  and  therefore  cannot  offer  an  opinion  at  present. 


M'Nab — A  RevUion  of  the  Species  of  Abies.  673 


LIT. — A  Beyisiok  of  thb  Spxcibs  of  Abies.  By  William  Ravsat 
M*Nab,  M.  D.,  Edinburgh,  Professor  of  Botanj,  Boyal  College  of 
Science  for  Ireland.     (With  Plates  46,  47,  48  and  49.) 

[Bead  June  26,  1876]. 

Last  year  I  presented  to  the  Boyal  Irish  Academy  a  paper  {aniea, 
p.  209),  in  which  the  anatomy  of  the  leaves  of  the  section  Tsuga 
of  the  genns  Pinus  was  described,  and  in  the  present  paper  I  propose 
to  continue  the  investigation  of  the  anatomical  structure  of  the  leaves  of 
the  same  great  genus.  The  sections  to  which  I  shall  now  direct  atten- 
tion are  Abies  of  Endlicher  and  Parlatore,  and  Pseudotsuga  of  Carri^re 
and  Bertrand,  the  former  including  a  considerable  number  of  species  of 
which  the  common  European  silver  fir  may  be  taken  as  the  type. 
Much  confusion  has  been  caused  by  Linnaeus  in  1753  falling  into  an 
•error  as  to  the  application  of  the  names  Picea  and  Abies — an  error 
which  was  corrected  by  Duroi  in  1771 ;  But  in  this  paper  I  shall  not 
follow  Parlatore  in  calling  the  common  silver  fir  (generally  known  by 
the  name  of  Abies  pectinata  of  Be  CandoUe)  Pinus  (Abies)  Abies  of 
Duroi ;  but  shall  adopt  the  more  commonly  used  A.  pectinata. 

Dr.  C.  E.  Bertrand*  enumerates  and  briefly  describes  the  anatomical 
characters  of  twenty-two  species  of  Abies.  All  Bertrand's  forms,  with 
a  single  exception,  I  believe  I  have  been  able  to  examine ;  and  while 
we  agree  in  many  most  important  points,  still  in  others  I  find  con- 
siderable discrepancies  in  our  results.  Perhaps  this  may  result  from 
an  examination  of  but  few  examples  of  each  species,  and  this  I  have 
tried  to  avoid  by  examining  as  many  specimens  as  I  could  obtain,  both 
living  and  dried.  A  very  large  number  of  specimens  have  been  exa- 
mined, and  many  thousands  of  sections  cut---the  greater  part  of  my 
spare  time  for  twelve  months  past  having  been  devoted  to  the  work. 

Great  confusion  exists  in  the  nomenclature  of  this  section ;  the 
synonymy  is  very  complex,  and  the  cultivated  forms  frequently  do  not 
agree  with  the  species  described  by  Botanical  authors.  It  has,  there- 
fore, been  difficult  in  many  cases  to  discover  what  the  true  plant  of 
the  original  describer  was,  but  I  have  been  very  fortunate  in  obtaining 
a  great  deal  of  information  regarding  the  cultivated  species  introduced 
into  Britain  within  the  last  twenty-five  years  from  my  father,  who  has 
cultivated  most  of  the  species  with  the  greatest  success,  and  whoso 
accurate  and  extensive  knowledge  of  this  genus  is  well  known.  All 
the  forms  introduced  by  Jeffrey  have  been  raised  from  seed  in  the 
Royal  Botanic  Garden  at  Edinburgh,  and  I  have  thus  been  able  to 
obtain,  from  the  Museum,  and  from  the  Edinburgh  Botanic  Ghirden, 
authentic  specimens  of  the  different  forms  for  examination.  To  Dr. 
Hooker  and  Professor  Oliver  I  am  very  deeply  indebted  for  permission 


*  Anatomie  Compar6e  dee  Tiges  et  des  Feailles  ches  les  Gn6tac^  et  lea  Goni- 
f  tires.    Paria,  1874. 

3  R  2 


674  Proceedings  of  the  Royal  Irish  Academy. 

to  examine  authentic  specimens  from  the  Kew  Herbarium,  many  diffi* 
culties  having  been  removed  by  their  kind  assistance ;  while  Pro- 
fessor Perceval  Wright  also  helped  me  greatly  by  his  kindness  in 
enabling  me  to  examine  the  authentic  specimens  in  the  Herbarium  of 
Trinity  College,  Dublin.  To  many  other  friends — ^Dr.  Moore,  of  Glas- 
nevin ;  Mr.  Fowler,  of  Castle  Kennedy ;  Mr.  Syme,  Elvaston  Nurseries ; 
Messrs.  Waterer,  Low,  and  Yeitch — my  best  thanks  are  also  due. 

Parlatore*  enumerates  and  describes  eighteen  species  and  two  varic* 
ties  in  his  section  Abies,  but  he  seems  in  some  instances  to  have  mixed 
up  two  or  more  anatomically  distinct  forms  under  one  name.  Each  form 
has  been  carefully  described,  and  a  figure  of  the  section  of  the  leaf 
given,  so  that  this  paper  may,  to  a  certain  extent,  be  useful  in  iden- 
tifying the  cultivated  species  in  our  gardens  and  nurseries. 

The  species  of  Abies  are  generally  separated  into  two  groups  by  the 
bracts  of  the  cones,  which  are  either  long  or  short.  Berti^d  separates 
two  groups  by  the  position  of  the  resin-canals.  In  the  present  paper  I 
have  adopted  a  geographical  arrangement,  as  I  find  that  the  forms 
most  related  anatomically  are  most  connected  geographically,  the 
outlying  forms  being  generally  the  most  distinct.  A  great  zone  of 
species  stretches  from  North  America,  by  Japan  and  the  Himalayas,  to 
Asia  Minor  and  Southern  Europe. 

The  section  Abies  of  Pinus  is  distinguished  by  having  the  leaves 
inserted  singly  into  the  stem,  by  their  not  being  placed  on  cushions, 
and  by  the  double  fibro-vascular  bundle.  The  second  section  mentioned 
in  this  paper  is  Pseudotsuga,  which  differs  in  having  a  single  fibro- 
vascular  bundle. 

I.  Abies,  Endl.,  Parlatore.     Genus  Abies,  Link.  Abies,  Bertrand. 

1.  Pinus  {Abies)  hracteata,  Don,  Trans.  Linn.  Soc.  xvii.  443;  Par- 
latore, D.  C.  Prod.,  vol.  xvi.,  pars  2,  p.  419,  No.  88.  Pinus 
venusta,  Dougl.  Abies  venusta,  Koch,  Dendrologie,  vol.  ii.  part  2, 
p.  210. 

Shoots  hairy  or  smooth.  Leaves  inserted  singly  all  round  the 
stem,  but  bent  so  as  to  form  two  lateral  rows;  occasionally  a  few 
directed  upwards.  Leaf  rigid,  linear,  twisted  above  the  base,  which 
is  slightly  narrowed  towards  the  orbicular  insertion,  widest  above  the 
twisted  part,  then  gradually  tapering,  contracting  suddenly  near  the 
sharp-pointed  apex;  upper  surface  bright  green  with  no  stomata, 
beneath  with  a  band  of  stomata  on  each  side  of  the  midrib,  there 
being  from  10  to  12  rows  of  stomata  in  each  band.  Leaves  from  1^  to 
2  inches  in  length,  and  about  iV  of  an  inch  wide.  Buds  covered  with 
pale  yellow  scales,  which  are  not  resinous. 

Transverse  section  of  leaf. — Leaf  flattened,  8 J  times  broader  than 
thick,  sides  rounded,  upper  surface  gently  curved  inwards,  below  with 


De  Caadolle,  Prodromus,  vol.  xvi.,  sect.  2,  pp.  419,  ei  teq. 


M'Nab — A  Revision  of  the  Species  of  Abies.  676 

41  prominent  midrib.  Hypoderma  well  developed,  a  continuous  band 
of  thickened  cells  running  underneath  the  epidermis  of  the  upper 
surface,  from  the  external  margin  of  the  one  resin-canal  to  the  ex- 
ternal margin  of  the  other.  At  the  rounded  margins  of  the  leaf  the 
hypoderma  consists  of  two  rows  of  cells.  The  hypoderma  is  also 
•developed  under  the  epidermis  covering  the  prominent  midrib  below, 
the  layer  of  cells  being  double  in  the  middle.  The  resin-canals  arc 
placed  one  at  each  side  of  the  leaf,  close  to  the  under  side,  and  sepa- 
rated from  the  epidermis  by  a  single  layer  of  cells.  The  pallisadc 
parenchyma  is  well  developed  on  the  upper  side,  and  below  there  is 
parenchyma  with  well-marked  intercellular  spaces  communicating  with 
the  stomata. 

Fibre- vascular  bundle  double,  the  parts  placed  close  together,  and 
having  a  few  thick  liber-like  cells  above  and  in  the  middle.  The 
'whole  is  surrounded  by  a  sheath. 

The  figure  (Plate  46,  fig.  1)  is  drawn  from  a  specimen  supplied  to 
me  by  Mr.  Syme,  Elvaston  Nurseries,  Borrowash,  Derby. 

Bertrand*  gives  the  following  characters  for  A.  bracteata: — 
Glands  touching  the  inferior  epidermis ;  no  stomata  on  upper  surface 
•of  leaf,  more  than  10  rows  of  stomata  in  each  band ;  no  pseudo-liber 
•cells  in  parenchyma  of  leaf ;  zone  of  hypoderm  continuous ;  leaf  mucro- 
nate. — In  the  d^erent  specimens  examined  by  me  the  same  characters 
were  found. 

Gordonf  describes  this  species,  and  directs  attention  to  the  buds, 
while  EochJ  gives  a  description  of  it  under  the  name  of  Finns  (Abies) 
venusta.  According  to  this  author  the  name  venusta,  Douglas  (1836), 
has  the  priority  by  one  year  of  that  of  bracteata,  D.  Don  (1837).  It 
lias  also  been  described  and  figured  by  Mr.  Andrew  Murray,  in  the 
Transactions  of  the  Botanical  Society  of  Edinburgh,  vol.  vi.,  p.  211, 
with  plates.  Koch  states  that  the  young  shoots  are  hairy,  while  Par- 
latore  says :  ''  Eamuli  glabri :  "  botii  states  occur  among  the  specimens 
•examined  by  me. 

P.  (Abies)  bracteata  is  one  of  the  most  distinct  species  of  the 
whole  section.  Five  different  specimens  have  been  examined  by  me — 
three  from  their  natural  habitats,  the  others  cultivated. 

I  am  indebted  to  my  valued  correspondent,  Mr.  Syme,  of  Elvaston 
Nurseries,  Borrowash,  Derby,  for  a  fine  cultivated  specimen  for  exami- 
nation, a  section  of  the  leaf  of  this  plant  being  the  one  figured.  The 
other  cultivated  specimen  examined  was  from  a  very  small  plant  in 
<7la8nevin  Garden,  kindly  given  to  me  by  Dr.  Moore,  and  in  it  the 
hjrpoderm  was  not  so  well  developed,  there  being  2  or  3  cells  omitted 
,  in  3  or  4  places,  but  it  agreed  in  all  other  characters. 

I  am  indebted  to  Dr.  Hooker,  C.B.,  P.R.S.,  and  to  Prof.  Oliver, 
F.  R.  S.,  for  permission  to  examine  two  specimens  in  Kew  Herbarium. 
One  is  a  specimen  collected  by  D.  Douglas  in  "  America  boreali-occi- 


♦  Op.  eit.,  p.  89.  t  The  Pinctum  (1858),  p.  146. 

X  Dendrologie,  vol.  ii.,  part  2,  p.  210. 


676  Procecdingi  of  the  Royal  Lish  Academy. 

dentalis;'*  the  other  was  marked  ''119,  Picea  bracteata,  W.  Lohb^ 
California."  These  specimena  of  Douglas  and  Lobb  hare  in  erenr 
respect  the  same  anatomical  characters  as  the  specimen  from  ElTaston 
Nurseries,  figured  in  the  paper. 

There  is  a  specimen  with  cones  in  the  Museum,  Bojal  Botanir 
Oarden,  Edinburgh,  presented  by  Mr.  Andrew  Murray  in  1859. 
The  leaves  of  this  specimen  do  not  differ  anatomically  from  those 
already  described. 

3.  Pinut  {Ahieti)  r$Ug%09a,  Humb.,  Bonpl.  and  Kunth,  Nov.  Gen.  et 
8p.  2,  p.  6 ;  Farlatore,  D.  C.  Frod.  vol.  xvi.,  para  2,  p.  420,  Xu. 
91. 

Shoots  hairy  or  smooth.  Leaves  inserted  singly,  and  not  very 
closely,  all  round  the  stem,  but  bent  so  as  to  form  two  lateral  row.n. 
Upper  side  of  shoot  with  leaves  directed  outwards  at  a  small  angle. 
Leaf  linear,  straight  or  curved,  slightly  twisted  above  the  base,  con- 
tracting  at  apex  into  a  point,  upper  surface  deep  green  with  no  sto- 
mata,  below  with  a  band  of  stomata  on  each  side  of  the  midrib,  there 
being  from  8  to  10  rows  in  each  band.  Leaves  from  1  to  1^^  inch 
in  length,  and  about  iV  inch  wide.  Buds  pale-coloured,  and  very 
resinous. 

Transverse  section  of  leaf. — Leaf  flattened,  nearly  three  timcR 
broader  than  thick,  sides  rounded,  upper  surface  with  a  central 
longitudinal  furrow,  below  with  a  slightly  prominent  midrib.  Hypo- 
derma  conspicuous,  forming  a  continuous,  or  only  very  slightly  inter- 
rupted, band,  extending  from  the  resin-canal  of  one  side  underneath  the 
epidermis  of  the  upper  surface  to  the  resin-canal  of  the  other  side : 
below  the  epidermis  of  the  midrib  a  series  of  hypoderm  cells  also  exists. 
The  resin-canals  are  two  in  number,  placed  close  to  the  epidermis  of 
the  under  side  of  the  leaf,  and  rather  near  the  margin.  The  pallisadc 
parenchyma  is  well  developed  on  whole  upper  part  of  leaf;  below,  the 
parenchyma,  with  intercellular  spaces  communicating  with  the  stomata, 
is  well  seen. 

Fibro-vascular  bundle  double,  surrounded  by  a  well-developed 
sheath ;  the  parts  of  the  bundle  are  not  widely  separated,  and  a  few 
thick  liber-like  cells  are  placed  superiorly. 

The  figure  (Plate  46,  fig.  2)  is  drawn  from  a  specimen  kindly  sap- 
plied  to  me  by  Mr.  Fowler,  gardener.  Castle  Kennedy,  N.  B. 

Pinus  (Abies)  religiosa  is  very  closely  related  to  P.  bracteata,  and 
Bertrand  says  that  the  two  do  not  differ  anatomically.  The  shape  of 
the  leaf  in  section  is,  however,  different,  and  the  thick  hypoderm  cells 
are  larger  and  more  interrupted  than  in  P.  bracteat«.  I  have  seen  two^ 
specimens  from  Castle  Kennedy,  one  figured  above,  the  other  in  the 
Museum,  Boyal  Botanic  Oarden,  Edinburgh.  It  has  a  cone,  ripened 
in  1867,  about  4  inches  long  by  2  wide,  with  projecting  bracts.  The 
specimen  from  Glasnevin  was  in  an  unhealthy  condition  when  ex- 
amined, and  has  the  hypoderm  less  developed  than  in  the  Castle 
Kennedy  specimens.  In  Kew  Herbarium  is  a  specimen,  marked  '*  Abiea 


M'Nab — A  Bevision  of  the  Species  of  Abies.  677 . 

religiose,  Guatemala,  Skinner;"  and  on  the  label  also,  ''Abies  hirtella. 
I)ifrert  ab  Ab.  religiosa  foliis  obtusissimis  emarginatis,  nee  acutis- 
simis."  This  seems  to  me  only  to  difPer  from  religiosa  in  having  tho 
hypoderm  cells  more  scattered,  and  it  resembles  in  every  way  the 
young  leaves  on  the  plant  of  religiosa  from  Glasnevin  Garden.  Some 
of  the  leaves  on  the  Castle  Kennedy  specimens  are  rather  obtuse,  so 
that  there  may  be  a  little  variation  in  this  interesting  form. 

I  place  religiosa  next  bracteata,  which  it  resembles  much  in  its 
leaves,  but  it  differs  in  its  cone. 

3.  Finus  (Abies)  amahilis,  Douglas,  Bot.  Mag.  Comp.  2,  p.  93  (not 
Parlatore).  Abies  grandisy  A.  Murray,  Syn.  Var.  Conif.,  p.  18 
(not  Douglas).  A.  grandis,  Lambert  (?).  Picea  lasiocarpa,  Balf.  in 
Jeff,  seeds,  p.  1,  t.  4,  f.  1  (not  Hook.).  Abies  spectabilis,  Herpin 
de  Fremont,  Bertrand,  Ankt.  Gn6t.  et  Conif.  p.  91  (not  Don). 

Shoots  densely  covered  with  small  dark  hairs.  Leaves  inserted 
singly  all  round  the  stem,  and  placed  very  close  together,  the  leaves 
on  the  under  side  of  the  stem  and  the  lateral  ones  forming  two 
lateral  rows  spreading  outwards,  those  on  the  upper  side  of  the  branch 
twisted  round  so  as  to  bring  the  upper  surfaces  of  the  leaves  superiorly : 
these  upper  leaves  all  point  to  the  apex  of  the  shoot,  nearly  parallel  to 
its  long  axis,  and  give  the  branches  a  very  peculiar  appearance. 
Leaf  linear,  more  or  less  twisted  at  the  base,  which  narrows  to- 
wards the  orbicular  insertion,  width  nearly  uniform,  apex  rounded 
and  emarginate,  upper  surface  very  bright  green  with  no  stomata,  be- 
neath with  a  band  of  stomata  on  each  side  of  the  midrib,  there  being 
from  8  to  10  rows  of  small  stomata  in  each  band.  Leaves  1  to  1^  inch 
long  by  about  -^  inch  wide.  Buds  covered  with  brown  scales,  and 
resinous. 

Transverse  section  of  leaf. — Leaf  flattened,  three  times  broader 
than  thick,  sides  rounded,  upper  surface  with  a  faint  longitudinal 
furrow,  the  midrib  not  prominent.  Hypoderma  well  developed,  form- 
ing a  continuous,  or  nearly  continuous,  layer  running  from  the  resin- 
canal  of  one  side,  under  the  upper  epidermis,  to  the  resin-canal  of  the 
other  ;  the  hypoderm  is  also  developed  in  the  middle  line  below. 
The  resin-cabsds  are  placed,  one  at  each  side  of  the  leaf,  close  to  the  in- 
ferior epidermis,  but  sometimes  having  a  layer  of  hypoderm  separating 
the  canal  from  the  epidermis.  The  pallisade  parenchyma  is  well  deve- 
loped on  the  upper  side,  and  below  is  parenchyma,  with  intercellular 
spaces  communicating  with  the  stomata. 

Eibro- vascular  bundle  double,  the  whole  surrounded  by  a  well- 
marked  sheath. 

The  figure  (Plate  46,  fig.  3)  is  drawn  from  a  specimen  supplied  to 
me  by  my  father,  from  the  Boyal  Botanic  Garden,  Edinburgh. 

The  peculiar  appearance  of  the  foliage  of  this  plant  is  well  shown 
in  Mr.  Murray's  fig^  (Syn.  Var.  Conif.  p.  19,  fig.  20),  an  appear- 
ance which  is  considered  characteristic  of  amabilis  of  Douglas.  It 
seems  probable  that  this  is  not  the  plant  meant  by  Douglas  to  be  called 


678  Ffvceedings  of  the  Royal  Irish  Academy. 

amabilis,  but  that  the  form  he  really  wished  to  bear  this  name  is  now 
known  as  Pseudotsuga  magnifica. 

I  have  examined  in  all  eleven  specimens  of  this  plant.  It  has  been 
sent  to  me  from  the  Boyal  Botanic  Garden  in  Edinburgh  as  the  troe 
amabilis  of  Douglas,  grafts  and  layers  from  Douglas'  plants  being 
there  cultivated.  I  have  also  received  it  from  Mr.  Syme,  of  Elvaston 
Nurseries,  as  the  true  amabilis  of  Douglas,  as  well  as  from  Mr.  Wtt- 
erer,  of  Knap  Hill  Nursery.  A  plant  of  it  was  noticed  last  September 
by  Dr.  Moore,  of  Glasnevin,  growing  near  Ambleside,  in  the  Lake 
District.  I  have  also  examined  five  native  specimens — ^three  in  Kew 
Herbarium,  from  the  Oregon  Boundary  Commission :  one  collected  in  St. 
JTuan  Island,  by  Dr.  Lyell,  in  1858 ;  another,  near  Lake  Chilnk- 
weyak,  B.  C,  Cascade  Mountains,  49^N.L.,  Dr.  Lyell,  1859;  and  the 
third,  Cascade  Mountains  to  Fort  Colville,  about  49°  N.  L.,  Dr.  Lyell, 
July,  1860.  A  section  of  the  leaf  of  one  of  these  is  figured  (Plate  46, 
fig.  3,  a.) 

In  the  Museum  at  the  Boyal  Botanic  Garden,  Edinburgh,  there  is 
a  cone,  about  4  inches  long,  with  a  few  leaves,  marked  **  Pinus  lasio- 
carpa,  409.  California,  Mr.  Jeffrey,  1853."  In  the  Herbarium  is  a 
specimen  of  the  same,  marked  **  Picea  sp.,  No.  409.  Mountains  east  of 
the  FaUs  of  Fraser's  River,  Sept.  27,  1851,  Jeffrey."  This  No.  409, 
Jeff.,  is  A.  lasiocarpa  of  Balfour  and  Oregon  Committee,  as  shown  by 
the  figure  given  by  Mr.  A.  Murray,  Syn.  Var.  Conif.  p.  25,  fig.  34. 
From  an  examination  of  both  the  cone  and  leaves,  I  have  no  difficulty 
in  identifying  this  plant  as  being  lasiocarpa  of  Balfour,  grandis  of 
Murray,  and  probably  of  Lambert,  and  amabilis  of  Douglas,  as  repre- 
sented in  our  gardens.  No  plants  of  this,  Balfour's  lasiocarpa,  seem  to 
have  grown  from  Jeffrey's  seeds. 

From  the  great  development  of  hypoderm,  I  place  this  species  next 
to  bracteata  and  religiosa.  The  cone  is  unlike  that  of  the  two  species, 
and  has  large  bracts,  which  do  not  project  beyond  the  scales. 

4.  Finw  (Ahies)  grandii^  Douglas,  Bot.  Mag.  Comp.  2,  p.  147 ;  Par- 
latore,  D.  C.  Prod.  xvi.  p.  427,  No.  104  (excl.  of  syn.).  Abies 
amabilis,  Murray,  Syn.  Yar.  Conif.  p.  20;  Koch,  Dendrologie, 
vol.  ii.  pt.  2,  p.  211.  Abies  Chrdoniana,  Carr.  Conif.  ed.  2, 
p.  298 ;  Bertrand,  Anat.  Comp.  Gn6t.  et  Conif.  p.  91. 

Shoots  smooth.  Leaves  inserted  singly  all  round  the  stem,  but 
bent  so  as  to  form  two  lateral  rows ;  occasionally  a  few  are  diluted 
upwards.  Leaf  linear,  twisted  at  the  base,  which  is  slightly  narrowed 
towards  the  orbicular  insertion ;  width  of  leaf  nearly  imif orm,  with  a 
rounded  emarginate  apex,  upper  surface  bright  green,  with  no  stomata, 
or  very  rarely  with  a  small  cluster  of  3  or  4  near  the  apex,  beneath 
with  a  band  of  stomata  on  each  side  of  the  midrib,  there  being  from 
7  to  8  rows  of  stomata  in  each  band.  Leaves  from  1  to  H  iiich 
long,  and  about  iV  inch  wide.  Buds  covered  with  resinous  brown- 
coloured  scales. 

Transverse  section   of  leaf. — Leaf  flattened,   about  three  times 


M'Nab— ul  Refririm  of  the  Species  of  Abies.  679 

broader  than  thick,  sides  ronnded,  upper  surface  with  a  faint  longitu- 
dinal furrow,  the  midrib  not  prominent.  Hypoderma  consisting  of  a 
few  scattered  cells  under  the  upper  epidermis,  one  or  two  at  the  sides 
of  the  resin-canals,  and  a  few  inferiorly  in  the  middle  line.  The  resin- 
canals  are  placed,  one  at  each  side  of  the  leaf,  close  to  the  epidermis  of 
the  under  surface.  The  pallisade  parenchyma  is  well  developed  on  the 
upper  side,  and  below  is  parenchyma  with  well-marked  intercellular 
spaces  communicating  with  the  stomata. 

Fibro-vascular  bundle  double,  the  parts  placed  close  together,  the 
whole  surrounded  by  a  well-marked  sheath. 

The  figure  (Plate  46,  fig.  4)  is  drawn  from  a  specimen  supplied  to 
me  by  my  father,  while  PI.  46,  fig.  4,  a,  is  from  a  specimen  sent  under 
the  name  of  A.  lasiocarpa. 

Much  confusion  exists  in  regard  to  this  species,  a  confusion  which 
«ecms  to  have  begun  at  the  very  beginning,  and  to  have  been  made 
«till  worse  by  the  Oregon  Association  distributing  several  plants  under 
one  name.  I  have  been  able  to  examine  many  specimens,  and  shall 
briefly  give  the  result  of  my  investigations. 

Specimens  of  grandis  have  reached  me  from  three  different  sources, 
all  purporting  to  be  grandis  of  Douglas.  The  first  comes  from  the 
Eoyal  Botanic  Gardeif ,  Edinburgh,  where  it  has  been  long  cultivated, 
and  my  father  sends  it  to  me  with  the  note  that  it  is  a  layer  from  one 
of  Douglas's  original  plants.  The  same  plant  is  cultivated  in  the 
Botanic  Garden,  Glasnevin,  and  is  marked  as  the  true  graiidis  of 
Douglas.  The  third  specimen  comes  from  Mr.  Barron,  of  Elvaston  Nur- 
aeries,  and  was  sent  to  me  by  Dr.  Masters.  ALL  these  have  the  same 
foliage,  and  the  same  peculiar  anatomical  structure  of  the  leaf,  and  the 
peculiar  scattered  hypoderm  cells.  Assuming,  then,  that  this  plant  is 
probably  the  true  grandis  of  Douglas,  an  examination  of  recently  in- 
troduced specimens  will  show  a  great  deal  of  confusion. 

In  the  Museum  and  Herbarium  of  the  Koyal  Botanic  Garden^ 
Edinburgh,  Jeffrey's  original  specimens  are  preserved,  and  I  have 
been  enabled  to  examine  them  carefully,  through  the  kindness  of 
Professor  Balfour,  F.R.S.  In  the  Museum  there  is  a  cone  in  a  net, 
iuid  lying  beside  the  cone  is  a  shoot  with  leaves,  bearing  a  label  in 
Jeifrey's  handwriting.  The  cone  is  5  inches  long,  by  2^  inches  wide, 
and  shows  the  short  pointed  bract.  There  seems  little  doubt  that  the 
cone  belongs  to  the  shoot,  as  shown  by  the  examination  of  other  spe- 
cimens.    On  the  label  is  the  following — 

Pieea,     Ko.  393. 
Along  the  banks  of  Eraser's  River,  from  the  Falls  to  the  Ocean. 

Sept.  30,  1861. 
There  is  another  cone  in  the  collection,  marked  "  P.  lasiocarpa  ? 
Jeffrey,  393."  The  cone  is  in  pieces,  and  seems  to  have  measured 
about  4  inches  by  2.  Ko  leaves  are  attached  to  this  specimen.  The 
acale  and  bract  is  the  same  as  that  figured  by  Mr.  Murray,  Syn.  Var. 
€onif.  p.  25,  figure  32. 


680  Proceedings  of  the  Royal  Irish  Academy. 

In  the  Herbarium  there  are  two  specimens,  one  with  part  of  an 
immature  cone,  the  other  with  the  whole  of  a  small  one,  also  immature. 
Bqth  are  marked  "  No.  393,  Jeffrey,  Picea,  sp."  One  bears  a  long^ 
printed  label ;  the  other,  with  the  entire  cone,  is  marked  by  my  father^ 
"  P.  Lowii." 

In  Kew  Herbarium  there  is  a  specimen  fron;  the  Oregon  Associa- 
tion, No.  393,  with  the  printed  label,  and  erroneous  date,  1852. 
Jeffrey's  No.  393  is,  undoubtedly,  the  same  as  grandis,  Douglas ;  but 
it  is  extensiyely  cultivated  as  Picea  lasiocarpa.  My  father  has  sent 
me  two  specimens  of  it  for  examination,  one  marked  **  Picea  lasio- 
carpa. Introduced  by  Jeffrey,  and  described  by  Mr.  Murray,"  meaning 
that  it  is  the  lasiocarpa  of  the  Oregon  Committee.  (See  Trans.  Ed.  Bot. 
Soc,  vol.  xi.  p.  326).  Mr.  Murray  (Syn.  Var.  Conif.  p.  24)  is  quite 
correct  in  stating  that  Jeffrey's  No.  393  is  Douglas's  grandis,  and  not 
lasiocarpa.  A  specimen  of  lasiocarpa,  received  from  Mr.  Barron  of 
Elvaston,  through  Dr.  Masters,  is  also  grandis ;  hence  Mr.  Barron's- 
conclusion  that  lasiocarpa  only  equals  grandis. 

Lasiocarpa  of  the  Oregon  Committee,  Jeffrey,  No.  409,  is  a  different 
plant,  already  noticed  as  amabilis. 

I  have  examined  sixteen  specimens — ^ten  cultivated,  and  six  na- 
tive— of  Picea  grandis,  Douglas,  and  have  received  it  under  three  diffe- 
rent names : 

A.  grandis,  Hort.  Edin.,  Hort.  Glasnevin.,  Hort.  Barron. 
P.  lasiocarpa,  Hort.  Edin. 
P.  amabilis,  Hort.  Glasnevin. 

There  is  a  specimen  in  Kew  Herbarium  from  Dr.  Lyell,  marked 
"Abies  grandis,  Dgl.?,"  from  the  Columbia  River,  lat.  46°-.49°N. 

A  specimen  in  the  Edinburg.h  Museum,  marked  "grandis,"  from 
Mr.  Andrew  Murray,  is  Lowiana. 

5.  PinuB  {Ahies)  Loujiana,  Gordon,  Supp.  to  Pinetum,  p.  63;  A. 
Murray,  Syn.  of  Var.  Conif.  p.  27.  A,  Parsansiana,  Hort.  A^ 
lasiocarpaf  Hort. 

Shoots  hairy.  Leaves  inserted  singly  all  round  the  stem,  but  bent 
so  as  to  form  two  lateral  rows;  occasionally  a  few  are  directed 
upwards.  Leaf  linear,  twisted  at  the  base,  some  only  slightly,  others 
twisted  through  half  a  turn,  width  nearly  uniform,  apex  rounded  and 
emarginate,  upper  surface  bright  green,  with  6  or  7  (or  fewer,)  rows 
of  stomata  in  a  central  band,  beneath  with  a  band  of  stomata  on  each 
side  of  the  midrib,  there  being  from  9  to  10  rows  in  each  band.  Leaves- 
1  to  2  inches  in  length,  and  about  ^^  inch  wide.  Buds  covered  with 
resinous  brownish  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  about  three  times  as- 
broad  as  thick,  sides  rounded,  upper  surface  with  a  faint  longitudinal 
furrow,  below  without  a  prominent  midrib.  Hypoderma  well  deve- 
loped at  the  margins  of  the  leaf ;  scattered  cells  under  the  upper  epi- 
dermis, and  a  few  cells  below,  under  the  fibro-vascular  bundle.     The 


M*Nab — A  Revision  of  the  Species  of  Abies.  681 

Tesin-canals  are  placed,  one  at  each  side  of  the  leaf,  close  to  the  under 
side.  The  pallisade  tissue  is  interrupted  above  by  the  presence  of' 
stomata. 

The  fibro-vascular  bundle  is  double,  the  parts  not  placed  very  close 
together,  the  whole  surrounded  by  a  well-marked  sheath. 

The  figure  (Plate  46,  fig.  5)  is  drawn  from  a  specimen  grown  in 
the  Royal  Botanic  Garden,  Edinburgh,  from  seed  sent  by  Jeffrey. 

I  have  examined  nine  specimens  of  this  plant,  six  of  them  being 
cultivated,  and  three  native  specimens.  In  the  Museum,  Boyal 
Botanic  Garden,  Edinburgh,  is  a  cone  with  a  shoot  having  leaves  tied  to 
it,  which  is  marked  "  Picea  Lowii  (P.  grandis).  Oregon,  Mr.  Jeffrey, 
1854."  The  cone  is  4  inches  long  by  2 J  inches  wide.  The  scale  and 
seed  are  both  large,  the  bract  being  very  short.  The  part  that  is  free 
from  the  scale  is  broader  than  long ;  the  margin  is  toothed,  with  a  sharp- 
pointed  apex,  indeed,  agreeing  very  well  with  Mr.  Gordon's  descrip- 
tion. The  number  in  Jeffrey's  list  is  not  given,  and  I  failed  to  find 
more  than  the  one  specimen  of  Jeffrey's.  I  have  little  doubt  that  th(y 
seeds  were  mixed  with  those  of  Jeffrey's  393  and  409,  and  the  three 
things  all  sent  out  as  P.  lasiocarpa,  Oregon  Committee;  hence  the 
name  it  receives  in  certain  gardens.  Lowiana  was  sent  home  by  Mr. 
William  Murray,  as  there  is  a  shoot  of  it,  without  a  cone,  in  the 
Museum,  in  the  Royal  Botanic  Garden,  Edinburgh,  marked  "Picca 
grandis.  California,  W.  Murray,  Esq.  Presented  by  A.  Murray,  Esq., 
1860."  In  Kew  Herbarium  is  a  specimen  marked,  "  No.  3.  California, 
—  Low,  Esq.,  Clapton."  It  is  also  cultivated  as  Parsonsiana,  and  I 
have  received  it  as  such  from  Edinburgh,  and  from  Mr.  Barron,  Elvas- 
ton  Nurseries,  per  Dr.  Masters. 

6.  Finns  (Abies)  eaneoloTf  Engelm.  Herb. ;  Parlatore,  D.  C.  Prod.,  xvi.^ 
pars  2,  p.  426,  No.  103.    Fieea  eoncolor,  Gordon,  Pinetum,  p.  155. 

Leaves  about  1^  inch  long,  and  iV  inch  broad,  linear,  curved,, 
twisted  at  base,  rather  obtuse  at  apex,  stomata  on  both  sides — about  15 
rows  on  the  upper  side,  and  two  bands  below,  each  with  about  8  or 
10  rows  of  stomata. 

Transverse  section  of  leaf. — Leaf  about  2^^  times  as  broad  as  thick, 
rather  tetragonous  in  form  although  much  flattened,  sides  rounded, 
upper  surface  convex  with  no  furrow,  below  with  a  rather  prominent 
midrib.  Hypoderma  developed  at  the  sides  of  the  leaf,  and  below  the 
epidermis  of  the  midrib,  occasionally  a  few  scattered  cells  in  other 
parts  of  the  leaf  between  the  rows  of  stomata.  The  resin-canals  are 
placed,  one  at  each  side  of  the  leaf,  close  to  the  lower  epidermis.  The 
pallisade  tissue  is  not  developed,  owing  to  the  presence  of  stomata  on 
both  sides  of  the  leal 

Fibro-vascular  bundle  double,  the  two  parts  rather  widely  separated, 
and  with  a  well-marked  sheath  surrounding  the  whole. 

The  figure  (Plate  46,  fig.  6)  is  drawn  from  the  specimen  in  Kew 
Herbarium  from  Fendler,  "  PL  Novo-Mexicano,"  No.  828,  1847. 


682  Proceedings  0/  the  Royal  Irish  Academy. 

This  species  is  yery  distinct  anatomicallj,  and  as  far  as  I  know  is 
.not  yet  in  oaltiyation,  not  having  received  it  from  any  of  our  gardens 
and  nurseries. 

M.  Bertrand  {loe.  eii,  p.  89)  gives  Abies  conoolor  as  a  synonpi 
of  Abies  grandis,  lindl.,  but  gives  the  characters  of  concolor  for  the 
species. 

7.  Pinui  lanoearpa.  Hooker,  Fl.  Bor.  Amer.  ii.,  p.  163,  (not  Balfour.) 
Ahie$  hifolia^  A.  Hurray,  Proc.  of  Royal  Hort.  Soc.  London,  iii^ 
p.  320.  P.  amabilis,  Parlatore,  D.  C.  Prod.,  vol.  xvi.,  p.  426,  No. 
102  (in  part).  ?  Pieea  amahilis,  Newberry. 

Leaves  of  two  forms,  those  on  ordinary  branches  from  j^  to  1} 
inch  long,  and  grooved  on  the  upper  side,  those  on  ttie  cone-bearing 
shoots  shorter,  and  without  the  groove.  Stomata  on  both  sides  of  the 
leaf,  above  with  many  rows  especially  near  the  apex,  below  with  two 
bands  on  each  side  of  the  rather  prominent  midrib,  there  being 
from  6  to  8  rows  in  each  band.  Leaves  either  pointed,  or  blunt,  or 
slightly  emarginate,  from  iV  to  iV  inch  wide. 

Transverse  section  of  leaf. — ^Leaf  (ordinary. branch)  flattened,  about 
three  times  as  broad  as  thick,  sides  rounded,  upper  surface  with  a 
central  longitudinal  furrow,  below  with  a  prominent  midrib.  Leaf 
(cone-bearing  branch)  tetragonal,  more  than  half  as  thick  as  wide,  wi^ 
no  furrow.  Hypoderma  developed  at  edges  of  leaf  below  epidermis  of 
midrib,  and  generally  superiorly.  Eesin-canals  in  the  parenchyma  of 
the  leaf,  and  remote  from  the  inferior  epidermis. 

Fibro-vascular  bundle  double,  and  surrounded  by  a  well-marked 
sheath. 

I  have  examined  nine  dried  specimens,  all  of  which  I  refer  to  this 
species.  The  first  is  a  specimen  in  Kew  Herbarium :  the  leaves  were 
sent  to  me  by  Prof.  Oliver,  and  labelled  "  P.  lasiocarpa.  Hook.  (sp. 
typica).  Coll.  Douglas."  This  specimen  first  showed  me  that  P.  lasio- 
carpa. Hooker,  was  not  P.  lasiocarpa  of  Balfour,  or  of  our  gardens.  A 
transverse  section  of  the  leaf  is  figured  in  Plate  46,  fig.  7.  My  valued 
correspondent,  Mr.  Syme,  of  Elvaston  Nurseries,  sent  me  leaves  of 
P.  bifolia,  A.  Murray,  got  from  M.  Koezl.  These  on  examination 
proved  to  be  the  same  as  P.  lasiocarpa.  Hooker.  The  two  forms  of  leaves 
were  sent  by  Mr.  Syme — both  the  grooved  and  quadrangular  fonns. 
One  of  the  leaves  is  figured  in  section  (Plate  47,  fig.  8).  Mr.  Syme 
adds  on  the  label  of  the  specimen  sent  to  me  the  note :  ''  M.  Boezl 
informs  me  that  it  is  not  very  handsome."  Young  plants  sent  by  Hr. 
Syme  were  also  examined,  but  they  did  not  present  the  distinctive 
features  of  the  species.  Five  specimens  from  Kew  Herbarium  were 
then  examined,  collected  by  Dr.  LycU  in  1860  and  1861,  and  in  the 
collection  of  the  Oregon  Boundary  Commission.  These  specimens  were 
collected  in  the  Cascade  Mountains,  Galton  range  of  Bocky  Mountains, 
and  along  the  Columbia  River,  through  10°  of  latitude,  viz.,  from  39^N. 
to  49°N. ;  and  on  the  Galton  range,  at  an  elevation  of  7000  feet.   These 


M*Nab — A  Itemion  of  the  Species  of  Abies.  683 

are,  in  fact,  the  types  of  Mr.  Murray's  "  bifolia/'  and  one  of  tlic 
specimens  is  marked  '^Ab.  amabilis,  Douglas,  fid.  Parlatore."  An 
unnamed  specimen  from  Douglas  also  exists  in  Kew  Herbarium  (Plate 
46,  fig.  7„  a.) 

When  examining  the^  specimens  in  the  Eojal  Botanic  Garden, 
Edinburgh,  I  found  a  specimen  marked  '^  Picea  magnifica  robusta. 
Oregon,  Mr.  Jeffrey,  1853."  Two  cones  and  a  few  leaves  were  pre- 
serred  in  the  Museum,  and  I  was  able  at  once  to  refer  the  specimen 
to  P.  bifolia  of  Murray,  or  P.  lasiocarpa,  Hooker. 

The  section  of  the  leaf  from  the  cone-bearing  branch  in  Kew  Her- 
barium with  the  label,  "  Colville,  Indian  name  *  Marcilp.*  Hub. 
East  side  of  Cascade  Mountains,  latitude  49^N.  Not  uncommon  up 
to  6000  feet  above  the  sea.  Aug.,  1860,"  is  figured  (Plate  47  fig.  9). 

After  the  most  careful  examination  of  these  specimens  I  am  com- 
pelled to  come  to  the  conclusion  that  P.  lasiocarpa  of  Hooker  is  a  good 
species  which  has  been  confounded  with  other  forms  by  subs€(|ucnt 
botanists.  I  further  conclude  that  bifolia  of  Murray  is  a  synonym  of 
P.  lasiocarpa^  Hooker.  From  an  examination  of  the  cones  of  grandis, 
magnifica,  and  bifolia,  I  find  that  it  is  very  difficult  to  separate  them  by 
external  characters,  all  being  hairy  or  "  lasiocarpous ; "  and  as  magni- 
fica and  bifolia  are  mixed  in  the  Museum  in  Edinburgh,  it  shows  that 
thoroughly  competent  botanists  may  confound  them.  By  an  examination 
of  the  bract,  the  two  can  be  readily  separated  :  the  bract  of  magnifica 
is  large,  while  that  of  bifolia  is  very  small.  If  we  bear  in  mind  that 
amabilis,  Douglas,  and  lasiocarpa.  Hooker,  were  described  within  a 
comparatively  short  time  of  each  other,  I  feel  constrained  to  consider 
that  the  two  things  are  and  were  distinct.  Purther,  when  we  consi- 
der M.  Roezl's  note,  mentioned  above,  that  it  is  not  a  handsome  plant, 
I  think  we  could  hardly  agree  with  Parlatore  in  calling  it  amabilis, 
Douglas.  The  scale,  but  not  the  bract,  of  amabilis,  Douglas,  is  figured 
in  Loudon's  ''Arboretum,"  and  he  mentions  that  the  bract  is  very  rhort 
and  pointed ;  in  fact,  the  cone  he  figured  was  bifolia,  Murray.  I  feel 
quite  confident  that  the  plant  Douglas  meant  to  call  amabilis  is  magni- 
fica of  Murray,  and  not  bifolia  of  Murray,  but  in  the  absence  of 
authentic  specimens,  I  think  we  should  retain  the  name  amabilis  for 
the  plant  long  cultivated  under  that  name,  and  retain  the  name  of 
lasiocarpa,  Hook.,  for  this  species,  while  we  use  A.  Murray's  name, 
magnifica,  for  the  species  which  Douglas  undoubtedly  meant  should 
be  called  amabilis. 

The  scale  and  bract  of  Jeffrey's  specimen  in  the  Museum  of  the 
Eoyal  Botanic  Garden,  Edinburgh,  were  examined.  The  cones,  two 
in  number,  are  6  inches  long,  by  about  2^  inches  wide.  Another 
one  in  the  same  collection,  7i  inches  long,  and  2  inches  wide,  marked 
*^  P.  Pinsapo,  from  Eonda  in  Spain,"  belongs  to  the  same  species,  viz., 
lasiocarpa,  Hook. 

This  species  is  probably  A.  amabilis  (Forbes),  Bertrand,  which 
Bcrtrand  says  does  not  differ  anatomically  from  A.  Fraseri. 


€84  Proceedings  of  the  Royal  Irish  Academy. 

6.  Pinus  (Abies)  Fraseriy  Pursh,  Fl.  Bor.  Amer.  2,  p.  639;  Parla- 
tore,  D.  C.  Prod.,  xvi.,  pars  2,  p.  419,  Ko.  90. 

Shoots  hairy,  the  surface  hroken  and  uneven  from  the  presence  of 
resin-canals.  Leaves  inserted  singly  all  round  the  stem,  bent  at  base 
«o  as  to  be  irregularly  two-rowed,  a  few  of  the  leaves  directed  up- 
wards. Leaf  linear,  bent  at  the  base  or  straight,  short,  leathery,  apex 
obtuse  or  emarginate,  upper  surface  deep  green  with  several  rows  of 
stomata  in  the  central  furrow,  beneath  with  a  band  of  stomata  on 
each  side  of  the  midrib,  there  being  from  8  to  9  rows  of  stomata  in 
each  band.  Leaves  about  ^  inch  in  length,  and  about  iV  inch  wide. 
Buds  large,  covered  with  yellowish-brown  resinous  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  three  times  broader  than 
thick,  sides  rounded,  upper  surface  with  a  well-marked  central  groove, 
below  with  a  distinct  but  not  very  prominent  midrib.  Hypoderma 
moderately  developed,  irregularly  scattered  below  superior  epidermis 
and  forming  a  very  much  interrupted  layer,  the  layer  continuous  at 
the  rounded  margins,  one,  rarely  two,  cells  thick ;  a  layer  of  hypoderm 
below  at  the  midrib  forming  a  single  layer  of  cells  with  a  few  scattered 
here  and  there  forming  a  double  row.  The  resin-canals  are  placed  in 
the  parenchyma  of  the  leaf,  and  separated  from  the  inferior  epidermis 
by  many  layers  of  chlorophyll-bearing  cells.  The  pallisade  parenchyma 
is  developed  at  each  side  of  the  groove  above,  but  is  defective  where 
the  stomata  are  present. 

Fibre- vascular  bundle  double,  surrounded  by  a  well-marked  sheath. 

The  figure  (Plate  47,  fig.  10)  is  drawn  from  a  specimen  supplied 
to  me  by  Mr.  Fowler,  gardener.  Castle  Kennedy,  N.  B. 

I  have  examined  four  specimens  of  this  species,  only  one  of  which 
is  from  a  cultivated  specimen.  There  is  a  cone  2^  inches  long  by 
1  broad,  in  the  Museum,  Royal  Botanic  Garden,  Edinburgh,  ripened 
at  Castle  Kennedy,  but  it  has  no  leaves.  The  other  three  specimens  I 
have  examined  are  from  Kew  Herbarium.  The  first  is  from  the  summit 
of  the  Hoosack  Mountains,  Massachusetts — Pinus-Fraseri,  Pursh.  The 
second  is  marked  "P.  balsamea.  Canada,  P.  Fraseri;"  the  third, 
"  Pinus  americanus,  Newfoundland.  Herb.  Forsyth."  About  the  two 
last  I  am  rather  doubtful,  as  I  find  it  very  difficult  to  separate  Fraseri 
4md  balsamea  by  anatomical  characters  only. 

9.  Pinus  {Abies)  balsatnea,  Linn.  Sp.  PI.  p.  1421 ;  Parlatore,  D.  C. 
Prod.  vol.  xvi.  pars  2,  p.  423,  No.  95. 

Shoots  hairy,  the  surface  broken  and  uneven  from  the  presence  of 
resin-canals.  Leaves  inserted  singly  all  round  the  stem,  but  bent  so 
as  to  form  two  lateral  rows,  a  few  being  directed  upwards.  Leaf 
linear,  twisted  at  the  base,  which  is  narrowed  towards  the  orbicular 
insertion,  apex  emarginate,  upper  surface  dark  green,  with  two  or  more 
rows  of  stomata  in  the  middle  line  near  the  apex,  beneath  with  a  band 
of  stomata  on  each  side  of  the  midrib,  there  being  about  ten  rows  of 
stomata  in  each  band.     Leaves  from  i  to  i  inch  long,  and  about 


M'Nab — A  Bemion  of  the  Species  of  Abies.  685 

tV  wic^  wide.  Buds  covered  with  brownisli  scales,  which  are  very 
resinous. 

Transverse  section  of  leaf. — Leaf  flattened,  about  three  times 
broader  than  thick,  sides  rounded,  upper  surface  with  a  faint  longi- 
tudinal furrow,  below  with  a  slightly  prominent  midrib.  Hypoderma 
wanting;  very  rarely  there  are  one  or  two  cells  at  the  rounded 
margfin,  and  one  or  two  below  the  fibre- vascular  bundles.  The  resin- 
canals  are  placed  in  the  parenchyma  of  the  leaf,  and  although  sometimes 
running  very  near  the  lower  surface,  are  always  separated  from  the 
epidermis  by  chlorophyll-bearing  cells.  The  pallisade  parenchyma  is 
well  developed  on  the  upper  side,  as  the  stomata  rarely  extend  down 
the  leaf  for  any  distance,  although  occasionally  a  single  row  may 
run  for  about  two-thirds  of  the  length ;  below,  the  parenchyma 
has  intercellular  spaces  communicating  with  the  stomata. 

The  fibre- vascular  bundle  is  double,  the  whole  surrounded  by  a 
well-marked  sheath. 

The  figure  (Plate  47,  fig.  11)  is  drawn  from  a  specimen  grown  in 
the  Royal  Botanic  Garden,  Edinburgh. 

I  have  examined  ^e  specimens  of  this  species :  one  specimen 
^own  in  the  Royal  Botanic  Garden,  Edinburgh  ;  one  from  Mr.  Syme, 
Elvaston  Nurseries;  two  specimens  are  from  Kew  Herbarium — one 
markid^'P.balsamea.  Canada,  Mr. Perceval;"  the  other,  ''P.balsamea, 
L.  Gonan ;"  the  fifth  specimen  is  from  the  Museum,  Royal  Botanic 
Garden,  Edinburgh.  The  leaves  examined  are  from  the  base  of  a 
<iluster  of  cones,  and  are  very  interesting,  as  having  a  considerable 
quantity  of  hypoderm  developed.  Like  P.  lasiocarpa,  this  species  is 
bifolious,  and  the  leaves  resemble  those  of  P.  Fraseri.  Indeed,  I  find 
it  very  difficult  to  separate  the  two  forms,  viz.,  Fraseri  and  balsamea, 
by  characters  derived  from  the  structure  of  the  leaf. 

10.  Pintu  {Abies)  stbiricaj  Turcz.,  Cat.  Baekal,  No.  1067  ;  Parlatore, 
D.  C.  Prod.  vol.  xvi.  pars  2,  p.  425,  No.  101.  Abies  sibiriea, 
Ledeb.  Fl.  Alt.  4,  p.  202.  Pieea  Pichta,  Loud.  Arbor.  Brit.  4, 
2338.     Abies  Pichta,  Forbes,  Pin.  Wob.  109,  t.  37. 

Shoots  hairy  or  smooth.  Leaves  inserted  singly  and  close  together 
4l11  round  the  shoot,  those  on  the  under  side  bent  to  form  two  lateral 
rows,  those  on  the  upper  side  directed  with  their  points  upwards  and 
forwards  towards  apex  of  the  shoot.  Leaf  linear,  twisted  above  the 
base,  which  is  slightly  narrowed  towards  the  orbicular  insertion,  width 
nearly  uniform  throughout  the  entire  length,  apex  rounded  or  slightly 
truncate,  upper  surface  dark  green,  with  no  stomata,  beneath  with  a 
band  of  stomata  on  each  side  of  the  midrib,  there  being  from  4  to  5 
rows  in  each  band.  Leaves  from  ^  to  1^  inch  long,  and  about  iV  inch 
wide.     Buds  brownish,  and  very  resinous. 

Transverse  section  of  leaf. — Leaf  flattened,  about  three  times  as 
broad  as  thick,  sides  rounded,  upper  surface  with  a  slight  longi- 
tudinal furrow,  below  with  a  very  faintly  prominent  midrib.  Hypo- 
•derma  entirely  absent.  The  resin-canals  are  placed  in  the  parenchyma 


686  Proceedings  of  the  Royal  Irish  Academy. 

of  the  leaf,  sometimes,  however,  rather  low,  but  always  separated  by 
chlorophyll-bearing  cells  from  the  lower  epidermis.  Pallisade  tissue 
well  developed  under  superior  epideimis,  the  parenchyma  with  inter- 
cellular spaces  communicating  with  the  stomata,  well  developed  below. 

Fibro-vascular  bundle  double,  with  one  or  two  thickened  cell* 
above  and  below,  the  whole  surrounded  by  a  well-marked  sheath. 

The  figure  (Plate  47,  fig.  12)  is  drawn  fpom  a  plant  cultivated  in 
Glasnevin  Garden,  and  kindly  supplied  to  me  by  Dr.  Moore. 

This  species  is  cultivated  in.  the  Botanic  Garden,  Glasnevin,  and  in 
the  Koyal  Botanic  Garden,  Edinburgh,  under  the  name  of  Pichta.  I 
have  also  received  it  from  Mr.  Syme,  of  Elvaston  Nurseries,  correctly 
named  sibirica.  In  Mr.  Syme's  specimen  a  single  thick  hypoderm 
cell  was  noticed  in  one  leaf  under  the  epidermis  covering  the  midrib 
below. 

11.  {Piwus  Abies)  Veitchii,  Pieea  Veitehii^  Lindley,  Gard.  Chron.,  Jan. 

1861.  Abies  Veitehii^  A.  Murray,  Sketch  of  Conif.  of  Japan^ 
p.  39.  Pinus  selenoUpiSy  Parlatore,  D.  C.  Prod,  zvi.,  p.  427, 
Ko.  105. 

Shoots  and  arrangement  of  leaves  not  observed.  Leaf  flat,  linear, 
grooved  on  upper  side,  apex  obtuse  and  emarginate,  above  glaucous- 
green,  with  no  stomata,  below  with  two  bands  of  stomata  on  each  side 
of  the  midrib,  there  being  from  6  to  7  rows  of  stomata  in  each  band. 
Leaf  from  i  to  1  inch  long,  and  about  iV  inch  broad. 

Transverse  section  of  leaf. — Leaf  flattened,  about  three  times  aa 
broad  as  thick,  sides  rounded,  upper  surface  with  a  longitudinal  furrow, 
below  with  a  slightly  prominent  midrib.  Hypoderma  only  slightly 
developed,  a  few  cells  being  placed  above  and  below,  touching  the  epi- 
dermis in  the  middle  line.  No  hypoderm,  or  rarely  a  single  thickened 
cell,  at  the  rounded  margin  of  the  leaf.  The  resin-canals  are  placed 
in  the  middle  of  the  parenchyma.  The  pallisade  parenchyma  is  well 
developed  above,  and  the  parenchyma  with  intercellular  spaces  below. 

The  fibro-vascular  bundle  is  double,  the  tissue  between  the  bundles 
and  the  well-developed  sheath  being  thickened. 

The  figure  (Plate  47,  fig.  13)  is  drawn  from  a  dried  specimen  in 
Kew  Herbarium. 

This  species  does  not  seem  to  be  in  cultivation,  and  the  only  speci- 
men known  to  me  is  that  in  Kew  Herbarium.  The  single  specimen 
has  two  labels,  viz. : — "  No.  946.  Abies  microsperma.  From  Fusi 
Yami.  2/63.  Yokohama;''  and  '*  813.  Picea  Veitchii,  Ldl.  Oldham 
legit." 

It  is  undoubtedly  the  Abies  Veitchii  of  description,  and  is  perfectly 
distinct  from  Abies  Veitchii  of  gardens. 

12.  Pinus  {Abies)  firma^  Antoine,  Conif.  70,  tab.  27,  bis,  Abies  firma^ 
Siebold  and  Zuccarini,  Flora  Japon.  ii.,  15,  tab.  107  (not  Parla- 
tore).  Abies  homolepis{f)y  Sieb.  and  Zucc.,  Flora  Jap.,  ii.,  17, 
t.  108.  Abies  brachyphylla,  Maxim.  PL  exsicc.  Pinus  brachy- 
phylla,  Pari.,  D.  C.  Prod,  xvi.,  2.,  p.  424. 


M'Nab — A  Revision  of  the  Species  of  Abies.  687 

Shoots  hfdry  or  smooth.  Leaves  inserted  singlj  all  ronhd  the 
stem,  but  bent  so  as  to  form  two  lateral  rows.  Leaf  linear^  twisted 
above  the  base,  < which  is  slightly  nairowed  towards  the  orbicular  inser- 
tion, width  tolerably  uniform,  or  slightly  greater  towards  the  apex, 
which  is  rounded  and  emarginate,  upper  surface  green,  occasionally 
with  a  few  stomata  in  a  patch  near  the  apex,  but  generally  without 
stomata,  beneath  with  a  band  of  stomata  on  each  side  of  Uie  promi- 
nent midrib,  there  being  from  10  to  11  rows  of  stomata  in  each 
band.  Leaf  from  i  to  1^  inch  in  length,  and  about  iV  inch  wide. 
Buds? 

Transverse  section  of  leaf. — Leaf  flattened,  three  times  as  broad  as 
thick,  sides  rounded,  upper  surface  convex,  with  a  well-marked 
central  furrow,  below  with  a  prominent  midrib.  Hypoderma  well 
developed,  forming  a  continuous  layer  extending  all  round  the  leaf, 
except  where  the  two  bands  of  stomata  occur  on  the  lower  surface  on 
each  side  of  the  midrib.  The  resin-canals  are  placed,  one  at  each  side 
of  the  leaf,  in  the  parenchyma  of  the  leaf,  and  separated  from  the 
lower  epidermis  by  many  chlorophyll-bearing  cells.  The  pallisade 
parenchyma  is  well  developed  on  the  upper  side,  and  below  is  the 
parenchyma  with  well-marked  intercellular  spaces  communicating 
with  the  stomata. 

Fibre- vascular  bundle  double,  the  two  parts  placed  rather  close 
together,  and  having  a  number  of  very  thick  liber-like  ceUs  below. 
The  whole  is  surrounded  by  a  well-marked  sheath. 

The  figure  (Plate  47,  fig.  14)  is  drawn  from  a  specimen  from  Kew 
Herbarium,  and  is  not  yet  in  cultivation  as  far  as  I  can  learn. 

I  have  only  seen  three  specimens  of  this  species,  all  of  which  are 
in  the  Kew  Herbarium,  and  I  am  indebted  to  Dr.  Hooker  and  Prof. 
Oliver  for  leave  to  examine  them.  The  first  is  marked  "812.  Abies 
firma,  S.  &  Z.  Nagasaki,  Japan,  1862.  Oldham.''  The  second,  from 
which  the  figure  is  drawn,  has  the  label,  *^  Ex  herb.  Hort.  Bot.  Pebx>pol. 
Maximiowicz,  iter  secundum.  Abies  firma,  S.  &  Z.  Japonia,  Nippon, 
1 864."  The  third  specimen  is  that  with  the  label, ' '  Ex  herb.  Hort.  Bot. 
Pctropol.  Maximiowicz,  iter  secundum.  Abies  brachyphylla,  Maxim. 
Japonia,  Yokohama,  1862." 

Very  much  confusion  exists  regarding  this  and  the  next  species 
(P.  bifida).  All  the  examples  cultivated  under  the  name  of  firma 
that  I  have  yet  seen  are  bifida.  As  the  specimen  marked  "  brachy- 
phylla" in  Kew  Herbarium  is  authentic,  it  will  be  seen  that  the 
species  described  by  Maximiowicz,  and  adopted  by  Parlatore,  must 
sink  as  a  synonym  of  firma,  Sieb.  and  Zucc,  if  the  plant  here  noticed  be 
Siebold  and  Zuccaiini's  species.  Bertrand  correctly  gives  the  charac- 
ters of  Abies  firma  as  here  defined.  Mr.  Andrew  Murray  (Conifers  of 
Japan,  p.  53)  mixes  up  firma  and  bifida ;  but  his  figures  98  and  99 
would  certainly  applv  very  well  to  firma,  and  fig.  108  to  bifida. 

Koch  (Dendrologie,  vol.  2,  pt.  2,  page  227)  adopts  Mr.  Murray's 
view  of  the  identity  of  firma  and  bifida,  but  adopts  the  name  of 
Abies  Momi,  Sieb.,  for  the  united  forms.  As  the  species  are  markedly 
distinct,  anatomically,  I  have  no  hesitation  in  separating  them ;  and 

B.  I.  A.  PBOC,  8SB.  n.,  VOL.  U.,  BCUXCE.  3  8 


688  Proceedings  of  the  Royal  Irish  Acaden^. 

at  the  same  time,  as  I  cannot  find  the  slightest  difference  to  exist 
between  finna  and  brachyphylla,  I  have  as  little  hesitation  in  uniting 
them. 

13.  Ptnui  {Ahie$)  bifida,  Ant.  Conif.  p.  79,  t.  31,  f.  2.  Abiei  hijiis, 
Sieb.  and  Zucc,  Flor.  Japon.,  2,  p.  18,  t.  109.  Ahtes  firwA,  A. 
Murray,  Conif.  of  Japan,  p.  53. 

Shoots  hairy  or  smooth.  Leaves  inserted  singly  all  round  the  stem, 
but  bent  so  as  to  form  two  lateral  rows,  rarely  a  few  pointing  dovn- 
waids  or  upwards.  Leaf  linear,  twisted  above  the  base  which  is  slightly 
narrowed  towards  the  orbicular  insertion,  then  gradually  tapexing, 
with  a  bifid  apex,  the  two  portions  being  very  acute;  upper  surface 
bright  green,  with  no  stomata,  beneath  with  a  band  of  stomata  on 
each  side  of  the  midrib,  there  being  from  10  to  12  rows  in  each  band. 
Leaves  varying  in  length  from  i  to  1^  inch,  about  iS  inch  wide  at 
widest  part.     Buds  covered  with  brownish  scales,  which  are  resinous. 

Transverse  section  of  leaf. — Leaf  flattened,  3^  times  as  broad  as 
thick,  sides  with  a  rather  acute  lateral  margin ;  upper  surface  convex, 
with  a  central  longitudinal  furrow,  midnb  not  prominent  belov. 
Hypoderma  well  developed,  forming  a  slightly  interrupted  row  of 
cells  running  from  the  margin  of  the  resin-canal  of  one  side  to  the 
margin  of  the  resin-canal  of  the  other  side ;  the  hypoderm  is  also 
developed  under  the  epidermis  covering  the  midrib.  The  resin-canals 
are  placed,  one  at  each  side  of  the  leaf,  generally  quite  close  to  the 
epidermis  of  the  under  side  of  the  leaf,  but  in  the  same  leaf  the  resin- 
canal  may  become  small,  and  be  separated  from  the  epidermis  by  one 
or  two  chlorophyll-bearing  cells.  The  ground  parenchyma  of  the  leaf 
is  distinguished  by  the  occurrence  of  numerous  large  thickened  pros- 
enchymatous  cells  or  idioblasts,  which  are  unbranched,  and  have  their 
long  axes  parallel  to  the  long  axis  of  the  leaf.  These  idioblasts  are  a 
special  peculiarity  of  this  species,  and  are  called  pseudo-liber  fibres 
by  Bertrand.  The  pallisade  tissue  is  well  developed  on  the  upper  side, 
and  below  is  the  parenchyma  with  well-marked  intercellular  spaces 
communicating  with  the  stomata. 

Fibre- vascular  bundle  double,  the  parts  placed  close  together,  with 
several  thickened  liber-like  cells,  sometimes  above  and  always  below 
the  bundles,  tho  whole  surrounded  by  a  sheath. 

The  figure  (Plate  47,  fig.  15)  is  drawn  from  a  specimen  supplied 
to  me  by  Messrs.  Yeitch  &  Sons,  Chelsea,  under  the  name  of  Abies 
firma. 

I  have  examined  five  specimens  of  this,  all  presenting  the  marked 
characteristics  of  the  species.  There  is  a  specimen  in  £ew  Herhfl- 
rium,  marked  A.  bifida,  Sieb.  and  Zucc,  which  is  the  same  as  this, 
but  I  have  not  examined  it  microscopically.  It  is  cultivated  in  the 
Boyal  Botanic  Garden,  Edinburgh,  under  the  correct  name  of  F- 
bifida,  and  there  is  another  plant,  differing  only  in  the  smaller  size  of 
the  leaves,  which  my  father  sent  as  P.  sp.,  Japan.  It  is  the  spceies 
cultivated  in  gardens  and  nurseries  as  Abies  firma,  and  under  that 


M*Nab — A  Remion  of  the  Species  of  Abies.  689 

name  I  have  received  it  from  Messrs.  Veitch,  and  Mr.  Fowler  of 
Castle  Kennedy.  Mr.  Fowler  sends  two  forms— one  marked  by  him  as 
■a  late  variety  ;  anatomically  they  are  the  same,  except  that  the  late 
variety  shows  great  irregularity  in  the  size  and  position  of  the  resin- 
canals,  being  normal,  in  the  lower  half  of  the  leaf,  but  in  the  paren- 
chyma, near  the  apex. 

This  species  can  at  once  be  separated  from  firma  by  the  presence 
of  the  remarkable  idioblasts  as  well  as  by  the  margin  and  apex  of  the 
leaf. 

Abies  homolepis,  Sieb.  and  Zucc,  I  have  not  seen,  but  from  Ber- 
trand's  description  of  the  leaf  I  would  consider  it  a  synonym  of  A. 
firma. 

Finns  holophylla,  Farlatore ;  Abies  holophylla,  Maxim.,  is  also  un- 
known to  me  except  by  Farlatore's  description  in  I) .  C.  Frod.,  vol.  xvi., 
pt.  2,  p.  424.     It  is  from  Mandschuria. 

14.  Finus  {Abiei)  Harry  ana,  n.  sp.     Abies  Veitchii,  Hort,  no^descr. 

Shoots  smooth.  Leaves  inserted  singly  all  round  the  stem,  but 
bent  so  as  to  form  two  lateral  rows,  a  few  projecting  upwards  and 
downwards.  Leaf  linear,  twisted  above  the  base,  widest  above  the 
twist,  getting  gradually  narrower,  then  suddenly  contracting  near  the 
apex  into  a  sharp,  simple,  or  bifid  point ;  upper  surface  bright  green, 
without  stomata  except  in  a  few  rare  cases  where  a  small  cluster  of  three 
or  four  occur  near  IJie  apex,  beneath  with  a  band  of  stomata  on 
oach  side  of  the  midrib,  there  being  from  7  to  8  rows  of  stomata 
in  each  band.  Leaves  from  ^  to  1^  inch  long,  and  about  iV  inch 
wide.    Buds  covered  with  pale  brown  very  resinous  scales. 

Transverse  section  of  leaf. — ^Leaf  flattened,  about  3^  times  as  broad 
as  thick,  sides  rounded,  upper  surface  with  a  longitudinal  furrow, 
below  with  a  slightly  prominent  midrib.  Hypoderma  well  developed, 
forming  a  slightly  interrupted  band,  extending  from  the  anterior  side  of 
the  resin-canal  of  the  one  side,  under  the  epidermis  of  the  upper  side 
of  the  leaf,  to  the  side  of  the  resin-canal  of  the  other  side ;  the  hypo- 
derma  is  also  developed  under  the  epidermis  of  the  midrib.  The  resin- 
canals  are  placed,  one  at  each  side  of  the  leaf,  close  to  the  lower 
epidermis.  The  pallisade  tissue  is  well  developed  on  the  upper  side, 
and  below  is  parenchyma  with  well-marked  intercellular  spaces  com- 
municating with  the  stomata. 

Fibro-vascular  bundle  double,  the  parts  placed  very  close  together, 
and  having  a  large  number  of  bast  fibres  below ;  the  fibro-vascidar 
bundles  and  the  bast  fibres  surrounded  by  a  well-marked  sheath. 

The  figure  (Flate  47,  fig.  16)  is  drawn  from  a  specimen  kindly 
supplied  to  me  by  Messrs.  Veitch  and  Sons,  Eoyal  Exotic  Nursery, 
Chelsea,  London. 

This  sharp-leaved  form  can  be  at  once  distinguished  from  the 
obtuse  emarginate-leaved  A.  Yeitchii.  Then  their  anatomical  cha- 
racters are  remarkably  distinct.    Yeitchii  in  the  Kew  Herbarium  has 

882 


690  Proceedingi  of  the  Royal  Irish  Academy. 

the  resiii-canalB  in  tbo  parenchyma  of  the  leaf,  and  possesses  very  little 
hypoderm.  The  same  characters  are  given  by  Bertrand  for  Yeitcbii 
so  that  there  can  be  no  doubt  that  we  have  both  had  the  same  plant 
under  examination.  The  Ycitchii  from  Yeitch's  Nursery ;  Boyd 
Botanic  Qarden,  Edinburgh ;  Mr.  8yme,  Elvaston  Nurseries ;  and  the 
Lawson  Nursery  Co.  (Limited),  EcUnburgh,  is  quite  distinct,  haTing 
the  resin-canals,  close  to  the  lower  epidermis,  and  the  hypoderm  weU 
deyeloped.  In  the  absence  of  sufficient  materials  for  description,  as 
the  cone  remains  unknown,  I  would  provisionally  name  it  Fmns 
Harryana,  after  Mr.  Harry  Yeitch,  the  head  of  the  firm  of  Yeitch  & 
Sons. 

The  leaves  of  this  species  rather  closely  resemble  in  general  form 
and  appearance  those  of  Pinus  (Pseudotsuga)  Fortunei,  Murray,  and 
it  seems  not  improbable  that  it  may  have  been  confounded  wi&  that 
plant  under  the  name  of  Jezocnsis.  It  is  a  Japanese  species,  but  is 
not  A.  Jezoensis,  Sieb.  et  Zuco.,  to  judge  from  tiie  figure. 

15.  Pinui  (Abiei)  Pindraw,  Boyle,  Himal.  p.  354,  t.  86;  Pailatore, 
D.  C.  Prod.  vol.  xvi.  pars  2,  p.  424,  No.  99.  Abtst  Pindrwi, 
Spach,  Hist.  Nat.  d.  Yeg.  Phan.  xi.  p.  423.  Pieea  Pindrow,  Loud, 
Arb.  Brit,  iv.,  2346. 

Shoots  hairy  or  smooth.  Leaves  inserted  singly  all  round  the  stem, 
but  bent  so  as  to  form  two  lateral  rows,  a  few  directed  upwards  and 
downwards.  Leaf  long  and  linear,  twisted  above  the  base,  narrowed 
towards  the  orbicular  insertion,  width  uniform,  the  apex  bifid,  witii 
two  narrow  sharp  points,  upper  surface  deep  green  with  no  stomata, 
beneath  with  a  more  or  less  conspicuous  band  of  stomata  on  each  ode 
of  the  midrib,  there  being  from  7  to  8  rows  in  each  band.  Leaves  from 
1  to  2i  inches  long,  and  about  iV  iiich  wide.  Buds  resinous,  covered  ^ 
with  brownish  scales. 

Transverse  section  of  leaf. — ^Leaf  flattened,  four  times  as  broad  as 
thick,  sides  rounded,  upper  surface  with  a  slightly  marked  longi-      ' 
tudinal  furrow,   midrib   not    prominent    below.     Hypoderma  well      I 
developed,  forming  a  continuous,  or  very  nearly  continuous,  band  from      I 
the  resin-canal  of  one  side,  under  the  epidermis  of  the  upper  surface,  to 
the  resin-canal  of  the  other  side ;  the  hypoderma  is  also  developed 
below  the  fibro-vascular  bundles.     The  resin-canals  are  placed,  one  at 
each  side  of  the  leaf,  close  to  the  epidermis  of  the  under  side.    The 
pallisado  parenchyma  is  well  developed  on  the  upper  side,  and  below 
is  the  parenchyma  with  well-marked  intercellular  spaces  commimi- 
cating  with  the  stomata. 

Fibro-vascular  bundle  double,  the  parts  rather  widely  separated,  a 
few  thick  cells  developed  both  above  and  below ;  the  whole  surrounded 
by  a  well-marked  sheath. 

The  figure  (Plate  47,  fig.  17)  is  drawn  from  a  specimen  kindly  sup- 
plied to  me  by  Dr.  Moore,  and  cultivated  in  Glasnevin  Oarden. 

Mr.  Syme,  of  Elvaston  Nurspries,  has  directed  my  attention  to  the 


M*Nab — A  Bemion  of  the  Species  of  Abies.  691 

fact  that  this  species  has  the  shoots  either  hairy  or  smooth,  hoth  in 
young  and  old  plants.  t 

Bertrand  (Joe.  ott,  p.  89)  says  that  Pindrow  has  "  TrSs-peu  d'hypo- 
<lcrma;"  this  I  have  only  found  in  exceedingly  young  leaves,  all 
others  examined  by  me  having  abunduice  of  hypoderm.  He  seems 
to  have  confused  the  species  from  the  Himalayas,  because  he  says, 
p.  91,  ''A.  Webbiana,  Lind.,  ne  difPere  pas  anatomiquement  de  r  A. 
Pindrow,  Spach,"  in  which  statement  I  cannot  concur. 

16.  Finw  {Abies)  Wehbiana,  Wall,  MSS. ;  Parlatore,  D.  C.  Prod.  xvi. 
pars  2,  p.  425,  No.  100.  Fintu  speetahUis,  Lamb.,  Pia.  ed.  2, 
vol.  2,  p.  3,  t.  2.  Abies  Webbiana,  Spach.  Fieea  Webbianaf 
Loudon,  Arb.  Brit.  iv.  p.  2346. 

Shoots  hairy  or  smooth.  Leaves  inserted  singly  all  round  the 
«tem,  but  directed  chiefly  towards  the  two  sides,  Uiose  on  the  upper 
side  with  their  points  directed  towards  the  apex  of  the  shoot,  and 
nearly  parallel  to  its  axis.  Leaf  long,  linear,  twisted  more  or  less 
■according  to  its  position  on  the  shoot,  base  narrowed  towards  the 
orbicular  insertion.  Breadth  of  leaf  uniform  through  most  of  its 
length,  slightly  contracted  near  the  bifid  apex,  the  two  portions  being 
«mall  and  very  sharp,  or  slightly  rounded ;  upper  surface  dark  green, 
with  no  stomata,  beneath  with  a  band  of  stomata  on  each  side  of  the 
midrib,  there  being  from  8  to  10  rows  in  each  band.  Leaves  from 
1  to  2i  inches  long,  and  about  iV  inch  wide.  Buds  brownish  and 
resinous. 

Transverse  section  of  leaf. — Leaf  about  four  times  as  broad  as  thick, 
fiides  with  a  well-marked  lateral  line,  upper  surface  convex,  with  a 
wcU-marked  longitudinal  fuirow,  below  with  a  slightly  prominent 
midrib.  Hypoderma  rather  well  developed,  forming  an  interrupted 
band  running  from  the  resin-canal  of  one  side,  under  epidermis  of 
upper  surface,  to  the  resin-canal  of  the  other  side ;  the  hypoderm  is 
4i1bo  developed  under  the  epidermis  of  the  slightly  prominent  midrib. 
The  resin-canals  are  placed,  one  at  each  side  of  the  leaf,  close  to  the 
-epidermis  of  the  under  surface.  The  pallisade  tissue  is  well  developed 
on  the  upper  side,  and  below  is  the  parenchyma  with  well-marked 
intercellular  spaces  communicating  with  the  stomata. 

Pibro-vascular  bundle  double,  with  thick  cells  above  and  below, 
the  whole  surrounded  by  a  well-marked  sheath. 

The  figure  (Plate  48,  fig.  18)  is  drawn  from  a  specimen  cultivated 
4it  Glasnevin  Garden,  and  kindly  supplied  to  me  by  Dr.  Moore. 

This  species,  like  A.  Pindrow,  has  the  shoots  either  glabrous  or 
hairy  when  young  or  old,  and  I  am  again  indebted  to  Mr.  Syme,  of 
Elvaston,  for  specimens  showing  this.  In  young  plants  the  hypoderm 
is  only  very  feebly  developed,  but  the  form  of  the  section  of  Uie  leaf 
at  once  separates  it  from  Pindrow. 

Mr.  Syme  sent  a  specimen  under  the  name  of  Picea  Webbiana 
ov2tta,  which  I  cannot  separate  anatomically  from  the  type. 

There  is  a  specimen  in  the  Museum,  Eoyal  Botanic  Garden,  Edin- 


692  Proceedings  of  the  Royal  Irish  Academij. 

burgh,  of  cone  and  leaves  from  Castle  Martyr,  Co.  Cork.  The  cone  i» 
about  6  inches  long  by  2^^  inches  broad.  On  examining  the  leaver 
attached  to  the  shoot,  they  are  found  to  have  the  same  anatomical 
characters  as  those  already  described.  In  the  same  Museum  are  two 
other  cones  without  leaves— one  from  Castle  Martyr  measuring  7  inches 
by  2\  inches,  and  the  other  from  Holkam  Hall,  which  only  measures 
51^  inches  in  length  by  2i  inches  in  breadth. 

17.  Pinus  {Abies),  sp.  nov.  (?) 

I  have  met  with  two  specimens  of  a  pine  closely  related  to  Pin- 
drew  and  "Webbiana,  which  on  further  investigation  may  turn  out  to 
be  new.  The  first  specimen  was  noticed  while  examining  the  specimens 
in  the  Herbarium  of  Trinity  College,  Dublin.  It  was  marked,  "  Ablest 
Webbiana,  Himalaya  occid.,  9,000  to  12,000,  Hook.  fil.  et  Thomson." 
The  leaves  are  1^  to  2  inches  in  length,  and  only  very  slightly  notched 
at  the  apex.  The  second  specimen  was  met  with  in  the  Museum, 
Eoyal  Botanic  Ghmien,  Edinburgh.  It  was  a  fine  cone-bearing  shoot, 
with  leaves,  and  had  been  grown  at  Castle  Kennedy,  in  Scotland. 
The  cone  measures  2^  inches  by  2,  and  the  leaves  are  long  and  nar- 
row, 2  inches  long  in  most  cases,  from  iV  to  iV  inch  wide,  and  only 
slightly  notched  at  the  apex. 

Transverse  section  oi  leaf. — Leaf  flattened,  about  four  times  as 
broad  as  thick,  sides  rounded,  upper  surface  with  a  slightly-marked 
longitudinal  furrow,  below  with  a  scarcely  prominent  midrib.  Hypo- 
derma  well  developed,  forming  a  continuous  (Castle  Kennedy  speci- 
men) or  slightly  interrupted  (Himalayan  specimen)  band  running  all 
round  the  leaf,  except  where  the  stomata  are  developed  in  a  band  on 
each  side  of  the  midrib.  The  resin-canals  are  in  the  parenchyma  of 
the  leaf,  and  separated  from  the  lower  epidermis  by  several  chlorophyll- 
bearing  cells.  The  pallisade  parenchyma  is  well  developed  on  the 
upper  side,  there  being  no  stomata  on  ^e  upper  epidermis,  and  below 
is  the  parenchyma  wi^  intercellular  spaces  communicating  with  the 
stomata,  of  wbich  there  are  about  10  rows  in  each  of  the  bands. 

Fibro-vascular  bundle  double,  with  thickened  cells  above  and 
below,  the  whole  surrounded  by  a  well-marked  sheath. 

The  figure  (PI.  48,  fig.  19)  is  drawn  from  the  Himalayan  specimen, 
which  is  smaller,  and  possesses  less  hypoderm  than  the  specimen  from 
Castle  Kennedy. 

The  cone  is  small,  in  this  resembling  Findrow,  but  as  it  was  un- 
broken the  bracts  could  not  be  described. 

Although  I  have  examined  eleven  different  cultivated  specimens  of 
Webbiana  and  Pindrow,  I  have  only  v^et  with  this  one  new  form  from 
Castle  Kennedy,  so  that  it  must  be  very  rare  in  our  gardens  and 
nurseries. 

I  abstain  from  giving  this  a  name,  as  the  synonymy  of  the  group  is 
obscure,  and  already  several  different  names  have  been  given  to  sup- 
posed species. 


M*Nab — A  Eemion  of  the  Species  of  Abies.  693 

18.  Pinus  {Abies)  pectinata.  Lam.  Fl.  Franq.,  ii.,  202  (1778).  Pinus 
Abies,  Duroi,  Obs.  Bot.,  p.  39 ;  Paxlatore,  D.C.  Prod.  vol.  xvi. 
p.  420,  No.  92  (in  part).  Pinus  Pieea,  Linn.  Sp.  Plant,  ii.,  1001 
(1753).     Abies  Pieea,  Koch,  Dendrologie,  vol.  ii.,  pt.  ii.,  p.  217. 

Shoots  hairy.  Leaves  inserted  singly  all  round  the  stem,  the  lower 
ones  bent  to  form  two  lateral  rows,  those  on  the  upper  side  more  or 
less  spreading,  and  bent  at  the  base  so  as  to  bring  the  superior  sur- 
face upwards,  the  inferior  surface  being  next  the  axis.  Leaf  linear, 
more  or  less  twisted  above  the  base  according  to  the  position  on  the 
stem,  apex  rounded  or  emarginate,  upper  sui-face  shining  dark  green 
with  no  stomata,  below  with  a  band  of  stomala  on  each  side  of  the 
slightly  prominent  midrib,  there  being  7  or  8  rows  of  stomata  in 
each  band.  Leaves  about  J  to  1  inch  in  length,  and  tV  inch  wide. 
Buds  covered  with  slightly  resinous  brown  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  about  2}  times 
broader  than  thick,  sides  rounded,  the  leaf  becoming  markedly 
thinner  towards  the  margins,  upper  surface  with  a  longitudinid 
furrow,  below  with  a  slightly  prominent  midrib.  Hypoderma  well 
developed,  a  slightly  interrupted  row  of  cells  running  from  near  the 
resin-canal  of  one  side  to  near  the  resin-canal  of  the  other  side.  The 
hypoderm  is  also  developed  below  the  epidermis  of  the  midrib.  Kesin- 
canals  placed,  one  on  each  side  of  the  leaf  in  the  parenchyma,  and  se- 
parated from  the  lower  epidermis  by  layers  of  chlorophyll-bearing 
cells.  Pallisade  tissue  well  developed  on  upper  side,  the  parenchyma 
below  with  intercellular  spaces  communicating  with  the  stomata. 

Fibro-vascular  bundle  double,  the  parts  placed  rather  close  together, 
the  whole  surrounded  by  a  sheath. 

The  figure  (Plate  48,  fig.  20)  is  drawn  from  a  specimen  from  Glas- 
nevin  Garden,  kindly  given  to  me  by  Dr.  Moore. 

Bertrand  (op.  eit  p.  90)  places  A.  pectinata  in  the  group  with  the 
rcsin-canals  touching  the  lower  epidermis,  and  adds  that  Nordman- 
niana  appears  to  be  little  different  from  A.  pectinata.  All  the  spe- 
cimens of  A.  pectinata  that  I  have  examined  have  the  resin-canals  in 
tlie  parenchyma  of  the  leaf,  so  that  I  conclude  that  the  A.  pectinata 
examined  by  Bertrand  was  a  variety  of  A.  Nordmanniana. 

All  the  specimens  examined  by  me  have  the  rcsin-canals  in  the 
parenchyma  of  the  leaf,  and  have  the  hypoderm  well  developed ;  the 
<iuantity  of  hypoderm  varies,  and  is  least  developed  in  the  plant  grow- 
ing in  the  Botanic  Garden,  Glasnevin.  This  very  interesting  tree  was 
raised  from  seed  by  Dr.  Moore,  the  seed  having  been  received  from 
the  Himalayas,  and  transmitted  to  Dr.  Moore  by  the  East  India  Com- 
pany. The  leaves  of  this  plant  are  wider,  and  have  a  sharper  or  less 
rounded  margin  than  the  typical  form ;  and  this,  taken  along  with  the 
feebler  development  of  the  hypoderm,  might  warrant  the  separation  of 
the  plant  under  the  name  of  variety  Mooreana.     (PI.  48,  fig.  21). 

The  leaves  from  a  cone-bearing  shoot  in  the  Museum,  Eoyal  Bo- 
tanic Garden,  Edinburgh,  were  examined,  and  found  to  have  a  more 
tetragonal  form,  there  being  no  longitudinal  furrow  visible.    The 


694  Proceedings  of  the  Royal  Irish  Academy. 

leaves,  therefore,  seem  to  me  inclined  to  be  of  two  shapes,  thus  resem- 
bling bifolia,  Murray  (lasiocarpa,  Hooker). 

Specimens  from  Edinborgh,  Glasnevin,  and  Cirencester,  have  been 
examined,  but  no  dried  specimens  from  native  habitats. 

19.  Pinus  {Ahies)  Norimanniana^  Stev.,  Bnll.  de  la  Soc.  d.  Nat.  de 
Mosc.,  xi.  45  (1838).  Pinus  Ahiss,  Dnroi;  Parlatore,  D.C.  Prod, 
vol.  xvi.,  p.  421,  No.  92  (in  part). 

Shoots  hairj  or  smooth.  Leaves  inserted  singly  all  round  the  stem, 
those  below  bent  so  as  to  form  two  lateral  rows,  those  above  directed 
more  or  less  upwards,  and  twisted  at  the  base  so  as  to  bring  the  upper 
surface  of  the  leaf  superiorly.  Leaf  linear,  more  or  less  twi^^  at  haac, 
apex  emarginate,  upper  surface  yellowish  green,  with  no  stomata, 
beneath  with  a  band  of  stomata  on  each  side  of  the  slightly  prominent 
midrib,  there  being  from  8  to  9  rows  of  stomata  in  each  band.  Jjeaves 
from  1  inch  to  1^  inch  in  length,  and  about  iV  inch  wide.  Buds  covered 
with  reddish-brown  resinous  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  three  times  broader  than 
thick,  sides  rounded,  upper  surface  only  faintly  grooved,  below  with 
a  scarcely  prominent  midrib.  Hypoderma  well  developed,  forming  a 
slightly  interrupted  band,  running  from  the  resin-canal  of  one  side, 
under  the  upper  epidermis,  to  the  resin-canal  of  the  other  side.  The 
hypoderm  is  also  developed  under  the  epidermis  covering  the  mid- 
rib. The  resin-canals  are  placed  at  each  side  of  the  leaf,  close  to  the 
under  surface,  and  separated  from  the  epidermis  by  a  single  layer  of 
cells.  The  pallisade  tissue  is  well  developed  above,  and  below  is  the 
parenchyma  with  intercellular  spaces. 

Fibro- vascular  bundle  double;  parts  placed  close  together,  and 
having  a  well-marked  sheath. 

The  figure  (Plate  48,  fig.  22)  is  drawn  from  a  specimen  from 
Olasnevin,  given  to  me  by  Dr.  Moore. 

The  difference  in  the  position  of  the  resin-canals  at  once  separates 
Nordmanniana  from  pectinata ;  the  shape  of  the  leaf  and  the  arrange- 
ment of  the  hypoderma  being  similar.  Plants  from  Edinburgh,  Glas- 
nevin,  and  Cirencester  have  been  examined,  but  none  from  native 
habitats.  The  leaves  on  the  cone-bearing  shoot  differ  from  those  on 
the  ordinary  branches  only  in  having  the  midrib  slightly  more  pro- 
minent. 

20.  Pinus  {Abies)  eiliciea,  Kotschy,  in  Osterr.  Bot.  Wochenblatt,  iii., 

409  (1853);  Parlatore,  D.  C.  Prod,  xvi.,  p.  422,  No.  93. 

Shoots  hairy  or  smooth.  Leaves  inserted  singly  all  round  the 
stem,  but  bent  so  as  to  form  two  lateral  rows;  several  point  up- 
wards, and  very  few  are  directed  downwards.  Leaves  linear,  twisted 
above  the  base,  especially  in  those  leaves  on  the  upper  part  of  the 
shoot  which  are  turned  so  as  to  have  the  superior  surface  upwards, 
apex  obtuse  and  emarginate,  upper  surface  green,  with  no  stomata. 


M'Nab — A  Hevimn  of  the  Species  of  Abies.  695 

l)eneath  with  a  band  of  stomata  on  each  side  of  the  midrib,  there 
being  from  7  to  8  rows  of  stomata  in  each  band.  Leaves  from  1  to 
1^  inch  in  length,  and  about  iV  u^ch  wide.  Buds  covered  with 
yellowish-brown  resinous  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  about  3^  times  as 
broad  as  thick,  sides  rounded,  upper  surface  with  a  very  slightly 
marked  longitudinal,  furrow,  below  without  a  prominent  midrib. 
Hypoderma  conspicuous,  forming  a  single,  more  or  less  interrupted 
layer,  running  from  the  resin-canal  of  one  side,  under  the  epidermis  of 
the  upper  side  of  the  leaf,  to  the  resin-canal  of  the  other  side  ;  there 
is  also  a  small  row  beneath  the  epidermis  in  the  middle  line  below. 
The  resin-canals  are  placed,  one  on  each  side  of  the  leaf,  near  the 
margin  and  close  to  the  epidermis  of  the  under  side  of  the  leaf.  The 
pallisade  tissue  is  well  developed  on  the  upper  side  of  the  leaf,  while 
below  is  the  parenchyma,  with  intercellular  spaces  communicating 
with  the  stomata. 

Fibro-vascular  bundle  double,  the  whole  surrounded  by  a  well- 
marked  sheath. 

The  figure  (Plate  48,  fig.  23)  is  drawn  from  an  original  speci- 
men of  Kotschy's,  No.  370,  in  the  Herbarium  of  Trinity  College, 
Dublin,  kindly  given  to  me  for  examination  by  Professor  Perceval 
Wright,  M.D. 

I  have  only  examined  three  specimens  of  this  pine— one  from  Mr. 
Syme,  of  Elvaston  Nurseries ;  one  from  Glasnevin ;  and  the  third  from 
Trinity  College,  Dublin,  Herbarium,  collected  by  Kotschy  in  Syria : 
''  inregionibusDaniae,  supra  Eden,  alt.  5000.  Die  28  Jul.  1855."  Ana- 
tomically it  is  the  same  as  P.  Nordmanniana ;  but  I  have  not  seen  the 
cones,  and  so  cannot  give  any  definite  opinion  as  to  its  distinctness. 
Bertiand  *  says  of  this  species :  **  Pas  d'hypoderm  sous  l'6piderme 
sup^rieur."  In  all  my  specimens  the  hjrpoderm  is  well  developed,  so 
that  probably  Bertrand  has  made  some  mistake. 

There  is  a  cone  in  the  Museum,  Boyal  Botanic  Garden,  Edinburgh, 
measuring  6  inches  by  2  inches,  and  marked  ''Abies  cilicica.  Crimea, 
P.  Lawson  &  Sons,  1856."  It  has  no  leaves,  but  after  most  careful 
examination  I  have  no  hesitation  in  referring  the  cone  to  Abies  bifolia, 
Murray, — ^the  P.  lasiocarpa,  Hooker. 

21.  Pifius  {Abies)  cephalonica,  Endl.,  Cat.  Hort.  Acad.  Yindob.  i.,  218. 
Pinus  {Abies)  fi,  cephahniea,  Pari.,  D.  C.  Prod,  xvi.,  2,  p.  422, 
No.  92.  Abies  oephaloniea,  Link.,  LinnsBa,  15,  p.  529.  Ficea  ee- 
phalonica,  Loudon,  Encyc.  Trees,  1039. 

Shoots  smooth.  Leaves  inserted  singly  all  round  the  stem,  but 
bent  so  as  to  form  two  lateral  rows,  many  pointing  upwards,  very 
few  projecting  downwards;  the  leaves  at  the  sides  of  the  shoot  are 
twisted  at  the  base ;  those  above  and  below  are  not,  or  only  very 


Anat.  Comp.  des  GnQt.  ct  Conif.  p.  89. 


696  Proceedings  of  the  Boyal  Irish  Academy. 

slightly,  twisted.  Leaf  linear,  narrow  at  base,  widest  aboye  base^ 
contracting  gradually  towards  the  apex,  and  then  suddenly  narrowing 
with  a  sharp  point ;  upper  surface  diark  shining  green,  generally  with 
no  stomata,  but  occasionally  with  a  partial  row  near  the  apex  of  the 
leaf  in  the  middle  line,  below  with  a  band  of  stomata  on  each  side 
of  the  midrib,  there  being  from  6  to  7  rows  in  each  band.  Leaves 
about  1  inch  in  length,  and  about  ^^  inch  wide.  Buds  covered  with 
yellowish-brown  resinous  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  about  three  times 
broader  than  thick,  sides  rounded,  upper  surface  nearly  flat  or  gently 
curved  inwards,  below  with  a  slightly  prominent  midrib.  Hypoderma 
well  developed,  forming  a  continuous  layer  from  the  resin-canal  of 
one  side,  under  the  upper  epidermis,  to  the  resin-canal  of  the  other 
side ;  at  the  margins  the  hypoderm  is  greatly  developed,  being  gene- 
rally three  cells  thick,  a  double  layer  of  hypoderm  below  the  double 
flbro- vascular  bundle.  The  resin-canals  are  placed  at  each  side  of 
the  leaf,  close  to  the  epidermis  of  the  under  side.  The  pallisade 
parenchyma  is  well  developed  on  the  upper  side,  while  below  is  the 
parenchyma  with  intercellular  spaces  communicating  with  the  stomata. 

Pibro- vascular  bundle  double,  the  whole  surrounded  by  a  well- 
marked  sheath. 

The  figure  (Plate  48,  fig.  24)  is  drawn  from  a  specimen  grown  in 
Glasnevin  Garden,  and  kindly  given  to  me  by  Dr.  Moore. 

A  plant  growing  in  the  Botanic  Garden,  at  the  Agricultural 
College,  Cirencester,  had  an  incomplete  row  of  stomata  on  the  upper 
side  of  the  leaf. 

Specimens  from  Glasnevin,  Edinburgh,  and  Cirencester  have  been 
examined.  One  from  the  Museum,  Boyad  Botanic  Garden,  Edinburgh, 
has  cones ;  and  the  leaves  from  the  cone-bearing  shoots  do  not  diflcr 
from  those  on  the  ordinary  branches,  except  that  the  leaf  is,  at  the  apex, 
slightly  bevelled  ofl  from  behind,  and  there  are  a  few  stomata  near 
the  apex. 

The  forms  described  as  Abies  BeginsD  Amelise,  Heldr.,  and  Abies 
ApoUinis,  Link.,  have  been  examined.  According  to  Mr.  Andrew 
Murray  (Lawson's  **  Pinetum,"  part  v.),  BeginsB  Ameliae  is  a  variety  of 
Abies  ApoUinis,  which  he  makes  a  species  distinct  from  A.  cephalonica. 
Mr.  Murray  says  of  KeginsB  Ameliae,  **foliis  crassis,  sub-acuminatis ; " 
but  I  cannot  observe  any  difference  between  the  leaves  of  this  form 
and  P.  cephalonica  except  that  the  hypoderma  is  less  developed.  The 
leaves  of  a  cone-bearing  shoot  of  cephalonica  are  like  those  figured  by 
Mr.  Murray  (Lawson,  "Pinetum,"  part  v.,  fig.  1)  for  ApoUinis,  while 
the  leaves  of  the  plant  cultivated  in  the  Boyad  Botanic  Garden,  Edin- 
burgh, difler  only  in  having  the  margin  less  rounded,  and  having  a 
sHghtly  developed  longitudinal  furrow  above. 

Mr.  Murray  (Pinet,  Brit.,  part  iii.)  gives  figures  of  P.  Panachaica, 
Heldr.,  and  reduces  that  species  to  P.  cephalonica.  From  an  examina- 
tion of  Mr.  Murray's  figures,  and  of  recent  specimens,  I  have  na 
hesitation  in  reducing  A.  Eeginas  Amclise,  Heldr.,  and  A.  Panachaica, 
Heldr.,  to  cephalonica,  whUe  ApoUinis  may  rank  as  a  variety,  bridging 


M*Nab — A  Revmon  of  the  Species  of  Abies.  697 

over  the  space  between  P.  cephalonica  and  P.  Nordmaimiaiia.     A  sec- 
tion of  the  leaf  of  A.  ApoUinis  is  figured  (Plate  48,  fig.  25). 

22.  Pinus  {Abies)  Pinsapo,  Boiss. ;  Parlatore,  D.  C.  Prod,  xvi.,  p.  422, 
No.  94  (in  part).  Abies  PinsapOy  Boissier,  Elench.  PI.  Nov. 
Hisp.  p.  84.    Picea  Pinsapo,  Loud.  Encycl.  of  Trees,  1041. 

Shoots  smooth.  Leaves  inserted  singly  all  round  the  stem,  and 
projecting  nearly  straight  out  in  all  directions  from  the  shoot,  but 
fewer  below  than  on  the  upper  surface.  Leaf  linear,  short,  rigid, 
scarcely  twisted  above  the  large  orbicular  base.  Leaf  narrowed  above 
insertion,  then  widening  to  its  full  extent  and  gradually  narrowing  to- 
wards the  elongated  sharp-pointed  apex ;  upper  surface  green,  with 
rows  of  stomata  generally  about  6  or  8  in  number,  and  placed  rather 
distantly  over  the  whole  upper  surface,  below  with  a  band  of  stomata 
on  each  side  of  the  midrib,  there  being  about  6  or  7  rows  in  each  band. 
Leaf  from  i  to  }  inch  long,  and  about  ^  inch  wide.  Buds  covered 
with  brownish  scales,  and  very  resinous. 

Transverse  section  of  leaf. — Leaf  flattened,  but  rather  tetragonal, 
only  about  twice  as  broad  as  thick,  sides  rounded,  upper  surface  con- 
vex, below  with  a  prominent  midrib.  Hypoderma  chiefly  developed 
at  the  margins  of  the  leaf,  and  above  and  below  the  midrib;  very 
much  interrupted  by  the  arrangement  of  the  stomata.  The  resin-canals 
are  placed,  one  at  each  side  of  the  leaf,  near  the  margin  close  to  the 
lower  epidermis,  but  separated  from  it  by  a  single  layer  of  hypoderm 
cells.  The  pallisade  tissue  is  much  interrupted  on  the  upper  side,  and 
below  is  the  parenchyma  with  intercellular  spaces  communicating  with 
the  stomata. 

Fibro-vascular  bundle  double,  the  whole  surrounded  by  a  well- 
marked  sheath. 

The  figure  (Plate  48,  fig.  26)  is  drawn  from  a  specimen  supplied 
to  me  by  Dr.  Moore,  and  grown  at  Glasnevin. 

I  have  only  examined  three  plants  of  this  species — ^two  from  Glas- 
nevin and  one  from  Cirencester.  Bertrand  places  this  species  in  his 
second  section,  but  I  have  never  found  the  resin-canals  in  the  paren- 
chyma of  the  leaf.  In  the  Museum,  Boyal  Botanic  Garden,  Edinburgh, 
there  is  a  cone  measuring  7i  inches  by  2  inches,  and  to  which  one  or 
two  leaves  were  attached.  It  is  marked ''  Picea  Pinsapo.  Prom  Ronda, 
in  Spain.  Mr.  Eobertson,  Trinity,  1859."  After  the  most  careful 
examination,  I  refer  it  to  Abies  bifolia,  Murray — the  P.  lasiocarpa  of 
Hooker. 

23.  Pinus  (Abies)  Baborensis^  Cosson.    Abies  Pinsapo  Pabarensis,  Cos- 
son,  Bull,  de  la  Soc.  Bot.  de  France,  viii.  607.     Abies  numidicaj 
De  Lannoy,  Rev.  Hort.  (1866),  106  and  168.    Pinus  Pinsapo, 
.  Parlatore,  in  part. 

Shoots  hairy.  Leaves  inserted  singly  all  round  the  stem,  but  bent 
so  as  to  form  two  lateral  rows,  a  few  projecting  upwards,  the  base 
of  the  leaves  on  the  upper  side  of  the  shoot  twisted.    Leaf  linear, 


698  Proceedings  of  the  Royal  Irish  Academy. 

base  much  smaller  than  in  Pinsapo,  rapidly  widening  to  its  full 
extent,  then  contracting  rapidly  near  the  blunt  or  emarginate  apex ; 
upper  surface  dark  green,  with  a  few  stomata  in  one  or  two  short  rows 
near  the  apex  of  the  leaf  in  the  middle  line,  below  with  two  bands  of 
stomata  on  each  side  of  the  midrib,  there  being  from  7  to  8  rows  in 
each  band.  Leaves  i^  to  f  inch  in  length,  and  about  i^  inch  wide. 
Buds  covered  with  yeUowish-brown  resinous  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  about  3 J^  times  as  broad 
as  thick,  sides  rather  sharp,  upper  surface  slightly  convex,  with  a 
faint  longitudinal  furrow,  below  with  a  slightly  marked  midrib. 
Hypoderma  chiefly  developed  at  the  margins  of  the  leaf,  there  being 
only  about  a  dozen  thickened  cells  placed  externally  to  the  resin- 
canal,  and  a  few  scattered  hjrpoderm  cells  under  the  upper  epidermis, 
and  a  few  in  the  middle  line  below  resin-canals,  near  the  margins  of  the 
leaf  and  placed  close  to  the  epidermis  of  the  lower  surface.  The 
pallisade  tissue  is  well  developed  on  the  upper  side  where  not  inter- 
rupted by  the  presence  of  stomata,  and  below  is  the  parenchyma  with 
intercellular  spaces  communicating  with  the  stomata. 

Fibre- vascular  bundle  double,  the  whole  surrounded  by  a  well- 
marked  sheath. 

The  figure  (Plate  48,  fig.  27)  is  drawn  from  a  specimen  supplied 
by  Mr.  Syme,  Elvaston  Nurseries. 

I  have  only  examined  four  specimens  of  this  plant,  which  differs 
so  strikingly  from  A.  Pinsapo  in  anatomical  characters.  Not  hav- 
ing seen  the  cone,  I  cannot  describe  it.  This  species  is  cultivated  in 
the  Royal  Botanic  Garden,  Edinburgh,  and  at  Glasnevin  Botanic 
Garden,  under  the  name  of  Abies  numidica,  and  is  sent  to  me  by  Mr. 
Syme,  with  both  the  names  **  numidica,"  and  **  Baborensis." 

24.  Pinua  {Abies),  sp. :  B^cky  Mountains,  Drummond. 

Shoots  hairy.  Leaves  inserted  singly,  and  very  close  together,  all 
round  the  stem,  but  bent  to  form  two  lateral  rows,  those  on  the  upper 
side  of  the  shoot  chiefly  directed  upwards.  Leaf  linear,  twisted  at  the 
base,  especially  on  upper  side  where  the  leaf  is  twisted  half  a 
turn,  base  orbicular,  width  of  leaf  rather  uniform,  apex  blunt,  the 
margin  of  the  leaf  sharp,  upper  surface  dull  green,  with  no  stomata, 
below  with  a  band  of  stomata  on  each  side  of  the  hardly  prominent 
midrib,  there  being  from  5  to  7  rows  in  each  band.  Leaves  from  J 
to  }  inch  long,  aud  about  A  inch  wide.  Buds  covered  with  yellowish- 
brown  resinous  scales. 

Transverse  section  of  leaf. — Leaf  flattened,  about  3^  times  as 
wide  as  thick,  sides  not  rounded,  but  with  a  sharp  transparent 
margin,  upper  surface  with  a  longitudinal  furrow,  below  with  the 
midnb  not  prominent.  Hypoderma  well  developed,  forming  an  inter- 
rupted band  from  the  outer  margin  of  the  resin-canal  of  one  side,  under 
the  epidermis  of  the  upper  surface,  to  the  resin-canal  of  the  other  side; 
the  hypoderma  is  also  developed  under  the  fibro-vascular  bundle.  The 
resin-canals  are  placed  at  each  side  of  the  leaf,  close  to  the  lower  epi- 


M*Nab — A  Revision  ofttie  Species  of  Abies. 

dermis.  The  paUisade  tissue  is  well  developed  on  the  upper  side,  and 
below  is  the  parenchyma  with  well-marked  intercellular  spaces  com- 
municating with  the  stomata. 

Fibro-vascular  bundle  double,  the  parts  placed  close  together, 
with  a  few  thick  liber-like  cells  above  and  in  the  middle.  The  whole 
is  surrounded  by  a  well-marked  sheath. 

The  resin-canal  has  a  double  wall — ^thd  inner  cells  smaller  and  with 
thin  walls,  the  outer  larger  and  with  thick  walls ;  this  thick- waUed 
layer  being  in  contact  with  the  lower  epidermis. 

Only  one  plant  of  this  species  has  come  under  my  notice.  It  has 
been  long  cultivated  in  the  Royal  Botanic  Garden,  Edinburgh,  and 
was  sent  to  me  by  my  father,  marked  "  Picea  sp.,  California,  old  tree.'* 
The  unique  plant  in  the  Edinburgh  Oarden  was  raised  from  seed  sent 
from  the  Rocky  Mountains  by  Brummond.  The  cone  being  unknown, 
I  have  not  attempted  to  name  it. 

The  figure  (Hate  49,  fig.  28)  is  drawn  from  the  plant  in  the  Edin- 
burgh Garden, 

The  leaf  is  somewhat  like  that  of  P.  pectinata,  but  the  plant  is  not 
a  handsome  one. 

II.  PsEUDOTSUGA,  Bcrtraud ;  Carri^ro  (in  part).  Abies,  Auct.  Tsugn, 
Carri^re.  Keteleeria,  Carri^re. 

1.  Pinua  {PseudoUuga)  nohilis,  Douglas,  MSS. ;  Parlatore,  in  D.  C. 
Prod,  xvi.,  pt.  ii.,  p.  419,  No.  89. 

Shoots  covered  with  fine  hairs.  Leaves  inserted  singly  all  round  the 
stem,  very  close  together,  the  leaves  on  the  lower  side  of  the  shoot 
directed  laterally  by  being  curved  outwards,  but  not  twisted  at  tho 
base ;  those  on  the  upper  side  of  the  shoot  aU  directed  upwards.  Leaf 
rigid,  linear,  more  or  less  falcate,  with  an  obtuse  apex,  upper  sur- 
face variable,  sometimes  with  numerous  stomata,  the  whole  surface 
being  pale  in  colour,  at  other  times  stomata  less  numerous,  or  even 
wanting,  and  the  colour  darker ;  beneath  with  a  band  of  stomata  on 
each  side  of  the  midrib,  between  the  midrib  and  the  resin-canal,  some- 
times with  stomata  between  the  external  margin  of  the  resin-canal  and 
the  edge  of  the  leaf,  there  being  5  to  7  rows  of  stomata  in  each  of  tho 
bands  between  the  midrib  and  resin-canal.  Leaves  about  1  to  H  uich 
in  length,  and  about  iV  u^ch  wide.  Buds  small,  dark-coloured,  and 
covered  with  resin. 

Transverse  section  of  leaf. — Leaf  broadly  triangular,  three  times 
broader  than  thick,  sides  rounded,  upper  surface  with  a  central  longi- 
tudinal furrow,  below  with  a  prominent  midrib.  Hypoderma  conspi- 
cuous, a  single  layer,  rarely  a  double  layer,  at  the  rounded  margin  of 
the  leaf ;  a  number  of  hypoderm  cells  above,  under  the  longitudinal 
furrow,  and  a  considerable  mass  two  or  more  cells  thick  at  the  prominent 
midrib  below  ;  the  hypoderma  is  interrupted  above  between  tho 
central  furrow  and  the  margin  by  the  presence  of  stomata.     Tho 


700  Proceedings  of  the  Royal  Irish  Academy. 

resin- canals  are  two  in  number,  placed  close  to  the  under  side  of  the 
leaf,  and  generallj  about  half-way  between  the  midrib  and  the  margin 
of  the  leci,  a  small  cluster  of  hypoderm  cells  often  placed  below  &e 
resin-canal.  Between  the  midrib  and  the  resin-canal,  on  each  side, 
inferiorly,  the  stomata  are  developed  and  the  hypoderma  is  wantmg. 
Between  the  resin-canal  and  the  margin  of  the  leaf  the  hypoderma  is 
either  continuous  or  interrupted  by  the  presence  of  a  few  stomata.  The 
pallisade  parenchyma  is  scarcely  developed  at  all,  owing  to  the  pre- 
sence of  stomata  on  the  upper  surface  of  the  leaf. 

Fibro-vascular  bundle  single,  and  surrounded  by  a  well-marked 
sheath. 

The  figure  (Plate  49,  fig.  29)  is  drawn  from  a  specimen  supplied  to 
me  by  my  father,  and  cultivated  in  the  Boyal  Botanic  Garden, 
Edinburgh.  Another  specimen  is  figured  (Plate  49,  fig.  29  a)  which 
was  sent  to  me  by  my  father  as  Picea  amabilis,  Douglas. 

Pseudotsuga  nobilis  is  a  bifolious  species,  the  leaves  on  the  cone- 
bearing  shoots  being  very  like  those  of  magnifica.  Indeed  it  is  very 
difficult,  even  in  cone-bearing  specimens,  to  separate  the  one  from 
the  other  anatomically. 

I  have  examined  many  specimens  of  nobilis  from  Glasnevin,  Edin- 
burgh, and  from  Mr.  Syme  of  Elvaston,  both  of  old  and  young  plants. 
Many  native  specimens  have  also  been  examined,  one  from  Douglas, 
in  Kew  Herbarium,  '*  P.  nobilis,  Sabine.  On  the  high  mountains  at  the 
Grand  Bapids,  on  the  Columbia  Biver,  and  near  the  base  of  Mount 
Hood,  1825;"  several  specimens  from  Jeffrey;  one  in  Kew  Herbarium, 
and  two  in  the  Edinburgh  collection.  One  of  these  is  No.  398, 
"  Chastey  Bull,  IT.  California,  Lat.  41^,  elevation  9,000  feet,  Oct.  12, 
1852."  The  leaves  on  the  cone-bearing  shoots  of  this  specimen  are 
remarkably  like  those  of  P.  magnifica,  but  the  long  projecting  scales 
of  the  cone  show  that  it  is  not  magnifica.  There  is  also  a  specimen 
of  nobilis  from  the  Cascades  of  Columbia,  Dr.  Gkmlener. 

The  leaves  of  the  type  specimen  of  P.  amabilis,  Sab.,  Douglas, 
sent  to  me  by  Professor  Oliver  are  those  of  P.  nobilis  (Plate  49, 
fig.  29  b),  but  may  be  those  of  magnifica. 

2.  Finw  {Pseudotsuga)  magnifica,     Abies  magnifica,  A.  Murray,  Proc 
Boyal  Hort.  Soc.  London,  iii.  p.  318. 

Shoots  covered  with  fine  hairs.  Leaves  inserted  singly  all  round 
the  6tem,  very  close  together,  leaves  on  the  lower  side  of  the  shoot 
directed  laterally  by  being  curved  outwards,  but  not  twisted  at  the 
base,  those  on  the  upper  side  of  the  shoot  rather  closely  appressed, 
not  twisted ;  upper  side  of  leaf  towards  the  branch,  and  directed  towards 
the  apex  of  the  branch,  almost  covering  the  shoot.  Leaf  rigid,  linear, 
more  or  less  falcate,  with  an  obtuse  or  rather  bluntly-pointed  apex, 
upper  surface  of  leaf  with  numerous  rows  of  stomata,  often  with  8  or 
more  rows,  and  giving  the  leaf  a  whitish  appearance ;  beneath  with  a 
band  of  stomata  on  each  side  of  the  midrib,  there  being  from  4  to  6 
rows  of  stomata  in  each  band.     Leaves  about  1  to  1 J^  inch  in  length. 


M*Nab — A  JRevision  of  the  Species  of  Abies.  701 

and  about  ^  inch  wide.  Buds  small,  dark-colonred,  and  covered  with 
resin. 

Transverse  section  of  leaf. — Leaf  slightly  quadrangolar,  rather 
more  than  one-half  as  thick  as  broad,  sides  rounded,  upper  surface 
-with  a  central  ridge,  below  with  a  prominent  midrib.  Hypoderma  well 
developed,  a  single  or  sometimes  a  double  layer,  at  sides,  below  epi- 
•dermis  of  midrib,  and  a  few  below  the  ridge  on  upper  side.  The  hypo- 
derma  is  interrupted  above  between  the  ridge  and  the  margin,  by  the 
presence  of  the  stomata.  The  resin-canals  are  two  in  number,  placed 
close  to  the  under  side  of  the  leaf,  and  generally  about  half-way  be- 
tween the  midrib  and  the  margin.  Between  the  midrib  and  the  resin- 
canal  on  each  side  inf eriorly,  the  stomata  are  developed,  and  occa- 
sionally a  row  of  stomata  is  seen  between  the  resin-canal  and  the 
margin  of  the  leaf.  The  pallisade  parenchyma  is  scarcely  developed, 
owing  to  the  presence  of  the  stomata. 

The  fibro-vascular  bundle  is  single,  and  surrounded  by  a  well- 
marked  sheath. 

The  figure  (Plate  49,  fig.  30)  is  drawn  from  a  specimen  kindly 
supplied  to  me  by  Mr.  Anthony  Waterer,  Knap  Hill  Nursery,  near 
Woking,  Surrey. 

I  have  examined  twelve  specimens  of  this  species — six  living,  and 
six  dried.  The  living  plants  were  from  Edinburgh ;  from  Mr.  Syme, 
Elvaston  Nurseries ;  from  Mr.  Anthony  Waterer,  Knap  Hill  Nursery ; 
and  from  Glasnevin ;  while  the  dried  specimens  were  from  Kew  Her- 
barium, and  Edinburgh  Museum.  It  is  cultivated  in  Edinburgh 
under  the  names  robusta  and  magnifica.  The  specimen  marked  **  ro- 
busta"  has  the  following  note  by  my  father :  ''  The  piece  of  P.  ro- 
busta is  from  a  layer  taken  from  the  original  plant  sent  home  by 
Douglas;"  and  he  adds,  ''I  think  it  likely  that,  in  certain  soils, 
P.  nobilis,  robusta,  and  magnifica,  may  aU  turn  out  to  be  the  same, 
although  distinct  in  the  garden  here."  Two  of  the  specimens  were 
raised  from  seeds  sent  home  by  Je&rey.  The  specimen  in  Glasnevin 
was  a  small  very  unhealthy  plant  from  Perth  Nurseries,  and  was  cul- 
tivated under  the  name  of  Picea  amabilis.  The  specimens  from  Mr.  Syme 
and  Mr.  Waterer  were  correctly  named  magnifica.  There  are  three 
specimens  of  this  species  in  the  Kew  Herbarium,  one  marked  ''  Sierra 
Nevada,  L.  California,  W.  Lobb ;"  figured  (Plate  49,  fig.  30  a),  and 
two  marked  *'  California,  H.Low,  Esq.,  Clapton."  These  are,  I  believe, 
the  types  of  Mr.  Murray's  magnifica.  There  are  three  specimens  in  the 
Edinburgh  collection ;  one  is  marked  **  Picea  robusta  magnifica,  1480, 
Jeffrey."  The  cones  are  6  inches  long  and  2  inches  wide.  The  bract  is 
long,  but  not  projecting,  and  has  an  evident  relationship  to  P. 
nobilis.  The  second  specimen  in  the  Edinburgh  Museum  is  marked 
**  Pinus,  sp.  nova,  from  California,  P.  Lawson  &  Son."  The  cone 
is  9  inches  long  by  2^  inches  wide,  and  is  bent  slightly.  The 
third  is  marked  "  P.  magnifica  robusta,  1480,  Oregon,  Mr.  Jeffrey, 
1853."  The  cone  is  8^  inches  long  by  2^  inches  wide,  and  is  slightly 
bent.  This  is  the  species  mentioned  in  lie  Trans.  Bot.  Soc,  vol.  vi., 
p.  370,  by  Mr.  A.  Murray  under  the  name  of  campylocarpa. 


702  Proceedings  of  the  Royal  LHah  Academy. 

It  is  certain  that  this  species  was  sent  home  by  Douglas,  as  it  has 
long  been  cultivated  in  the  Edinburgh  Botanic  Garden,  under  the 
name  of  robusta,  the  plant  being  a  layer  of  Douglas's  unique  specimen. 
It  was  also  sent  by  Jeifrey,  who  called  it  amabilis,  Douglas,  and  I  have 
no  doubt  whatever  that  Jeffrey  was  perfectly  right  in  so  naming  it* 
The  cone  is  exactly  like  that  of  P.  lasiocarpa,  Hook,  (bif  olia,  Murray) ; 
and  one  of  the  specimens namedin the  Edinburgh  Museum 'T.  magnifica 
robusta,  1480,  Oregon,  Mr.  Jeffrey,  1853,"  is  bifolia  of  Murray.  It 
has  also  been  sent  to  Low  by  Mr.  Lobb,  and  described  by  Mr.  Murray 
under  my  father's  MSS.  name  of  magniffca. 

3.  Pinus  {PseudoUuga)  DavidiatMy  Bertrand,  Anat.  Compar.  des  Gn6t. 

et  des  Conif .  p.  82. 

This  species  is  from  Thibet,  and  is  described  by  Bertrand,  but  I 
have  not  seen  it.  According  to  Bertrand  it  is  allied  to  Pinus  Fortunei, 
but  has  stomata  on  both  sides  of  the  leaf. 

4.  Pinus  (Pseudotsuya)  Fortunei,  Parlatore,  D.  C.Prod.  p.  430,  Ko.  112. 

Abies  Fortumi,  A.  Murray,  Proc.  Hort.  Soc.  Lend.  iii.  421 
(1862).  PseudoUuga  Jezoensis,  Bertrand,  cp.  eit,  p.  83.  Pieea 
Jezoensis,  Carr.  (?) 

8hoot8  hairy.  Leaves  inserted  singly  all  round  the  stem,  scattered^ 
forming  two  lateral  rows.  Leaf  linear,  twisted  above  the  base,  widest 
above  flie  twist,  remaining  tolerably  uniform  until  about  J  of  length 
from  apex,  then  narrowing  into  a  sharp  projecting  point ;  upper  sur- 
face dark-green,  with  no  stomata  (rarely  a  few  near  the  apex  of 
certain  leaves),  beneath  with  a  band  of  stomata  on  each  side  of  the 
midrib,  there  being  about  16  rows  of  stomata  in  each  band.  Leaves 
from  j^  to  1  inch  in  length,  and  about  ^  inch  wide.    Buds  (?) 

Transverse  section  of  leaf. — ^Leaf  flattened,  about  five  times 
broader  than  thick,  sides  rounded,  slightly  angular  near  resin-canal, 
upper  side  nearly  flat,  or  slightly  concave,  below  with  a  slightly  pro- 
minent midrib.  Hypoderma  well  developed,  forming  an  interrupted 
band  running  from  the  resin-canal  of  one  side,  under  the  epidermis 
of  the  upper  surface,  to  the  resin-canal  of  the  other  side :  a  cluster  of 
hypoderm  cells  below  the  midrib.  The  resin-canals  are  placed,  one 
at  each  side  of  the  leaf,  close  to  the  epidermis  of  the  under  surface,  but 
separated  from  it  by  a  layer  of  thick  hypoderm  cells.  The  pallisade 
parenchynia  is  well  developed  on  the  upper  side,  and  below  is  paren- 
chyma with  intercellular  spaces  communicating  with  the  stomata. 

Eibro-vascular  bundle  single,  but  sometimes  divided  into  as  many 
as  six  small  portions.  Bast  cells  developed  below,  and  the  whole  sur- 
rounded by  a  tolerably  evident  sheath. 

The  figure  (Plate  49,  fig.  31)  is  drawn  from  a  specimen  kindly 


•  See  Transactions  Edinburgh  Botanical  Society,  xL,  p.  326. 


M'Nab — A  Eevision  of  the  Species  of  Abies.  703 

Hupplied  to  me  by  Messrs.  Veitch  and  Son,  Royal  Exotic  Nursery, 
Chelsea. 

I  have  only  examined  one  specimen  t)f  this  plant,  received  from 
Messrs.  Veitch  under  the  name  of  Ahies  Jezoensis.  There  is  no  diffi- 
culty in  identifying  the  specimen  with  Mr.  Murray's  A.  Fortunei,  a 
Chinese  species.  It  is,  however,  very  like  the  plant  sent  out  by 
Messrs.  Veitch  as  Abies  Veitchii,  and  I  strongly  suspect  there  is  some 
confusion  yet  to  be  cleared  up  about  these  Japanese  plants.  Veitchii, 
of  Hort.  Veitch,  is  not  Veitchii  of  Kew  Herbarium,  but  resembles 
P.  Fortunei,  excepting  that  the  leaves  are  smaller.  Veitchii  (Hort.) 
may,  therefore,  be  Jezoensis,  and  thus  F.  Fortunei  must  stand  as  the 
name  of  this  most  interesting  plant. 

5.  Pintta  {Pseudotiu^a)  Dauglasiiy  Sabine,  Lamb.,  Gen.  Finns,  2  ed., 
vol.  iii.  tab.  21.  Picea  Douglasiif  Link,  in  Linnaea,  xv.  524. 
Pseudotsuffd  Douglasii,  Carr.,  Trait.  General  des  Conif.  2  ed., 
p.  256. 

Shoots  smooth.  Leaves  inserted  pingly  all  round  the  stem,  but 
bent  so  as  to  form  two  lateral  rows,  occasionally  a  few  are  directed 
upwards  and  downwards.  Leaf  linear,  twisted  near  the  base,  which 
is  narrowed  to  the  small  insertion,  breadth  uniform  for  greater  part  of 
hmgth,  apex  rounded,  upper  surface  bright  green,  with  no  stomata, 
beneath  with  a  band  of  stomata  on  each  side  of  the  midrib,  there  being, 
from  5  to  6  rows  of  stomata  in  each  band.  Leaves  from  1  to  1^  inch 
long,  and  about  iV  inch  wide.  Buds  covered  with  yellow  resinous 
scales. 

Transverse  section  of  leaf. — Leaf  flattened  about  2^  times  as 
broad  as  thick,  sides  rounded,  upper  surface  with  a  longitudinal 
groove,  below  with  a  slightly  prominent  midrib.  Hypoderma  very 
variable,  in  some  leaves  very  well-developed,  in  others  almost  absent 
on  upper  side.  The  resin-canals  are  placed  one  at  each  side  of  the 
lejif,  close  to  the  epidermis  of  the  under  side.  The  pallisade  paren- 
chyma is  well  developed  on  the  upper  side,  and  below  is  parenchyma 
with  well-marked  intercellular  spaces.  In  the  parenchyma  of  the  leaf 
are  developed,  in  North  American  specimens  only,  peculiar  stellate 
idioblasts,  which  ramify  between  the  ordinary  parenchymatous  cells. 
Fibro-vascular  bundle  single,  surrounded  by  a  well-marked  sheath. 
The  figure  (Plate  49,  fig.  32)  is  drawn  from  a  specimen  supplied 
by  Mr.  Syme,  which  shows  the  absence  of  hypoderma  in  cultivated 
plants  and  agrees  well  with  others  from  Edinburgh  and  Glasnevin. 
Plate  49,  fig.  32a,  represents  a  specimen  of  Douglasii  from  Kew  Her- 
barium. It  is  marked  **  Abies  sp.  nova,  Douglasii  ?  Rocky  Mountains. 
Independence  Bluff,  Nuttall."  It  has  the  cone  of  Douglasii,  but  the 
development  of  hypoderm  and  idioblasts  separates  it  from  all  the  culti- 
vated specimens  I  have  yet  seen.  It  is  the  same  as  Wright's  No.  1885, 
from  New  Mexico,  which  Parlatore  refers  to  P.  Douglasii.  The  third 
specimen  figured  (Plate  49,  fig.  32b.)isFendler's,  No.  829,  which  Par- 
latore refers  to  amabilis.      Either  the  species  is  variable,  or  else  we 

B.*!.  A,  PKOC,  SEB.  II.,  VOL.  IT.,  8CIBNCE.  3  T 


704  Proceedings  of  the  Royal  Imh  Academy, 

haye  one  species  in  cnltivation  and  another  known  only  by  Herbariam 
specimens,  viz.,  Fendler,  No.  829 ;  Wright,  No.  1885  ;  and  Abies,  sp. 
Donglosii  ?  Rocky  Mountains,  Nuttall.  I  am  indebted  to  Prof.  Perce- 
Tal  Wright  for  the  opportunity  of  examining  the  specimens  of  Poidler 
and  Wright  in  the  Herbarium  of  Trinity  College.  The  leaves  of  the 
£ne  old  plant  of  Bouglasii,  in  the  Eoycd  Botanic  Garden,  Edinbuigb, 
hare  neither  hypoderm  nor  stellate  idioblasts. 


Hardman— On  the  Carboniferous  Dolomites  of  Ireland.     705 


LV. — A  CoNTEEBunoir  to  the  Histoet  op  Dolomite. — The  Doloiotes 
OP  the  Cakboniperous  Limestone  op  Ireland.  By  Edward  T. 
HARDJkiAN,  F.  C.  8.,  F.  R.  a.  S.  I.,  of  the  Geological  Survey  of  Ire- 
land.    (With  Plates  41  and  42.) 

[Bead  May  8, 1876.] 

As  Bischof  well  remarks,  "  no  rock  has  attracted  greater  attention 
than  dolomite ;"  and  very  many  theories  as  to  its  origin  have  been  put 
forward ;  the  principal  of  which  are  based  on  the  idea  of  the  meta- 
morphism,  in  some  way,  of  limestone  rocks,  varying  the  means  of  such 
changes  according  to  the  views  of  different  authors. 

(1).  Yon  Buch's  supposition  involves  the  introduction  of  magnesia 
into  limestone,  as  the  result  of  the  eruption  of  volcanic  rocks  in  the 
neighbourhood,  producing  vapours  of  magnesic  chloride.* 

(2).  Haidinger  suggested  that  the  effect  was  produced  by  the 
action  of  sulphate  of  magnesia  on  limestone,  sulphate  of  lime  and 
carbonate  of  magnesia  being  formed.f  But  as  this  cannot  be  effected 
in  the  ordinary  way,  it  is  assumed  that  under  the  influence  of  great 
heat  and  pressure  it  might  take  place.  It  will  be  remembered,  how- 
over,  that  most  dolomitic  deposits  of  themselves  utterly  refute  such  an 
hypothesis. 

(3).  Yon  Morlot  put  forward  a  similar  theory,  having,  as  he  sup- 
posed, found  that  when  sulphate  of  magnesia  and  carbonate  of  lime 
were  heated  in  a  sealed  tube  to'  a  temperature  of  392°  F.,  a  double 
^carbonate  of  lime  and  magnesia  was  formed,  together  with  gypsum. J 
But  Dr.  Sterry  Hunt  has  shown  that  in  this  case  the  so-called  dolo- 
mite was  really  but  a  mixture  of  carbonate  of  lime  with  carbonate  of 
magnesia, §  nor  did  he  find  that  Marignac's||  substitution  of  chloride  of 
magnesium  for  the  sulphate  yielded  any  better  results. 

All  these  well-known  theories  not  only  presuppose  in  every  case 
the  action  of  igneous  rocks,  and  a  high  temperature,  but  also  the 
evolution  of  gaseous  sulphuric  and  hydrochloric  acids,  in  order  to 
obtain  the  necessary  supplies  of  magnesia  from  the  eruptive  rocks  them- 
selves. In  our  present  state  of  chemical  and  geological  knowledge, 
it  will  therefore  be  doing  no  violence  to  the  scientific  reputation  of 
their  originators,  to  say  that  they  may  now  be  looked  upon  rather  as 
<,'uriosities  of  geological  literature.  .    • 

(4).  Forchammer  appears  to  refer  the  formation  of  dolomite  to 


♦  See  Bischof,  Chem.  Geol.,  vol.  iii.,  155  ef  seq.    Also  Chem.  and  Geol.  Eesays, 

Sterry  Hunt,  44  D.,  &c.,  p.  81,— Ann.  de  Chem.  and  Phys.,  xxiii.,  296. 

t  Bischof,  op.  eit.y  p.  158. — Pogg.  Ann.,'lxxiv.,  p.  591. 

X  Bischof,  loc.  cit,,  also  N.  Jahrb.  fiir  Min.,  1847,  862. 

J  Chem.  and  Geol.  Essays  T.  Sterry  Hunt. 

II  For  the  experiment,  see  Bischof,  vol.  iii.,  p.  159. 

3T2 


706  Proceedings  of  the  Royal  Lnsh  Academy. 

the  reaction  of  spring- water,  containing  a  large  percentage  of  carbonate 
of  lime,  with  sea- water,  at  a  very  high  temperature.*  But  this  theory, 
which  bears  a  slight  degree  of  resemblance  to  that  of  Hunt  (see  pott)t 
will  not  answer,  since  many  dolomites,  e.  g.  those  the  carboniferous 
formation  in  Ireland,  not  only  are  interstratified  with  limestone,  but 
actually  the  same  bed  may  be  highly  fossiliferous  limestone  in  one 
place,  and  pass  into  dolomite  in  another.  Such  instances  are  common,, 
and  it  is  clear  that  such  a  rock  could  not  have  been  deposited  from 
boiling  sea-water. 

(6).  Dr.  T.  Sterry  Hunt  apparently  endeavours  to  strike  the  happy 
medium  between  the  Wemerists  and  the  Plutonists,  but  still  hi* 
theory  will  be  found  not  to  account  for  the  interstratification,  and 
passage  into  each  other  of  fossiliferous  limestones  and  dolomites.  It 
supposes  the  reaction  of  river  waters  holding  in  solution  carbonate  of 
soda,  with  sea- water  contained  in  shallow  basins,  and  further  decom- 
positions of  chloride  of  calcium  and  subsequently  of  sulphate  of  mag- 
nesium into  bicarbonates  of  calcium  and  magnesium  respectively ;  the 
former  being  precipitated  first,  but  that,  under  certain  conditions, 
a  mixture  of  the  two  maybe  precipitated  together.  **  The  subsequent 
action  of  heat  upon  such  magnesian  sediments,  either  alone  or  mingled 
with  carbonate  of  lime,  has  changed  them  into  magnesite  or  dolomite."f 
I  am  at  a  loss  to  see  why  Dr.  Hunt's  own  objection  to  Von  Morlot's 
theory  does  not  also  apply  to  this.  In  both  cases  only  a  mixture  of 
the  two  carbonates  is  obtained  in  the  first  instance,  and  the  element  of 
sufficient  heat  may  be  supposed  as  well  in  the  one  case  as  in  the  other. 
But  besides  this,  the  whole  theory  fails  altogether  to  account  for  the 
carboniferous  dolomites  of  Ireland:  for  the  facts  that  it  is  possible 
to  produce  specimens  from  the  same  bed,  of  fossiliferous  unaltered 
limestone,  and  of  true  dolomite,  and  that  beds  of  dolomite  lie  above  and 
below  highly  fossiliferous  limestone,  as  I  shall  show  hereafter.  More- 
over, the  number  and  development  of  the  fossils  with  which  the  lime- 
stones abound,  as  well  as  the  general  stratigraphical  character  of  the 
deposits,  and  the  extremely  capricious  manner  in  which  the  dolomites 
occur,  show  that  they  could  not  have  been  formed  in  a  series  of  shallow 
seas,  unless  we  admit  an  extraordinary  series  of  changes  of  level,  and 
of  physical  features,  during  the  period  of  the  formation  of  the  carboni- 
ferous limestone — a  position  which  is  quite  untenable. 

I  take  the  dolomites  of  the  carboniferous  limestone  as  a  test  of  these 
theories,  not  only  because  I  am  best  acquainted  with  them,  but  be- 


♦  Biscliof,  viii.,  p.  161. — Also,  Ann.  de  Chem.  and  Phys.,  xxiii.  Also,  Report 
Brit.  Assoc.,  1849  (Birmingham),  Transactions  of  Sections,  p.  36,  where  an  abstract 
of  his  views  is  given. 

t  Chem.  and  GeoL  Essays,  pp.  80-90.  On  the  Chemistry  of  Dolomites  and 
Gypsums,  also  pp.  91-92,  309,  et  multis  aliis,  I  should  not  refer  so  particularly 
to  this  in  the  present  instance,  but  that  Dr.  Hunt  applies  his  theory  to  the  formation 
of  **  all  magnesian  limestones." 


Hardman — On  the  Carbon  if erom  Dolomites  of  Ireland.      707 

cause  while  they  are  of  extremely  frequent  and  extengive  occurrence  in 
Ireland,  they  are  also  found  under  perhaps  the  most  favourable  con- 
ditions for  the  determining  any  points  with  regard  to  either  Plutonism 
•or  physical  phenomena. 

On  the  subject  of  Irish  dolomites,  two  valuable  papers  are  extant. 
Many  years  ago  Dr.  Scouler  communicated  his  views  on  that  subject 
to  the  Geological  Society  of  Dublin  ;*  his  opinion  being  that  dolomite 
was  produced  by  a  metamorphism  of  the  original  limestone,  and,  follow- 
ing Virlet,  he  considered  the  change  to  be  readily  accounted  for  by  the 
infiltration  of  water  charged  with  carbonate  of  magnesia;  which 
water  would  at  the  same  time  remove  some  of  the  carbonate  of  lime. 
But  an  important  point  in  his  paper  is  that  he  considers  dolomite  to 
occur  usually  near  some  source  of  magnesia— either  near  an  igneous 
or  ancient  palaeozoic  rock,  or  close  to  a  break  in  the  strata,  where  a 
thermal  spring  might  have  existed.  This  is  a  point  which  I  shall 
presently  dwell  upon,  as  many  dolomites  occur  under  circumstances 
which  do  not  agree  with  any  of  these  conditions,  and  where  the  supply 
of  magnesia  is  far  below  that  of  lime. 

The  reading  of  the  above  paper  led  Dr.  Apjohn  to  make  several 
4inalyses  of  Irish  dolomites,  which  he  has  published  in  the  same 
journal. f  The  conclusions  he  came  to  as  to  the  origin  of  dolomites 
appear  to  be  that  they  are  original  formations ;  first,  because  they  are 
oftim  fossiliferous,  and,  secondly,  because  their  composition  is  definite. 
At  the  same  time  he  suggests  that  some  dolomites  may  have  been 
produced  by  the  solvent  action  of  carbonated  water  on  limestones  con- 
taining some  magnesia,  in  removing  carbonate  of  lime,  until  at  last 
the  rock  would  consist  of  the  two  carbonates  in  the  correct  propor- 
tion.J 

Probably  the  most  comprehensive  account  yet  published  of  the 
•dolomite  question  is  that  given  by  Bischof ,  who,  in  his  classical  work  on 
chemical  geology,  has  discussed  nearly  all  the  foregoing  views,  together 
with  many  of  those  held  by  other  writers.  He  dismisses  as  impro- 
bable all  those  which  call  in  the  aid  of  volcanic  or  Plutonic  agencies, 
and  shows  that  the  action  of  water  by  infiltration  through  limestone 
<^an  alone  explain  the  processes  of  dolomitization ;  that  is,  either  by 


♦  Observations  on  Beds  of  Dolomite  which  occur  in  connexion  v-ith  the  Carboni- 
ferous Limestones  indifferent  parts  of  Ireland.  By  John  Scouler,  M.D.,  &c.,  Jour. 
GeoL  Soc.  Duh.,  vol,  i.,  pp.  382-6. 

-t-  Analyses  of  some  Irish  Dolomites.  By  James  Apjohn,  M.D.,  &c.  Jonr.  (}eol. 
Soc.  Dub.,  vol  i.,  pp.  369  et  »eq, 

t  I  am  inclined  to  adopt  a  modification  of  the  above  hypothesis,  viz., 
that  the  greater  part  of  the  carbonate  of  magnesia  was  originally  secreted  along 
with  the  carbonate  of  lime,  but  that  dolomite  is  a  tnie  metamorphic  rock — the 
alterations  being  due  to  the  extraction  of  the  surplus  of  carbonate  of  lime.  Some 
so-called  dolomites  having  the  crystalline  structure  and  the  obliteration  of  fosaila 
en  regie,  are  by  no  means  of  definite  composition ;  they  usually  contain  a  consider- 
4ible  percentage  of  uncombined  carbonate  of  lime,  which  dissolves  out  in  weak, 
•acid. 


708  Proceedings  of  the  Royal  Iriah  Academy. 

the  action  of  water  holdinp:  carbonate  of  magnesia  in  solution,  pene- 
trating the  rock,  and  depositing  carbonate  of  magnesia,  while  at  the 
same  time  removing  a  portion  of  the  carbonate  of  lime ;  or,  as  he 
admits,  it  may  occur  in  some  cases  by  the  simple  removal  of  carbonate 
of  lime  from  a  magnesian  limestone  by  water  containing  carbonic 
acid ;  the  result  being,  of  course,  a  gradual  increase  in  the  proportion 
of  carbonate  of  magnesia.  While  admitting  this  process,  which  was 
first  suggested  by  Grand]  ean,  to  be  possible — as  he  shows  by  twa 
experiments,  which  prove  carbonate  of  lime  to  be  actually  more 
soluble  than  carbonate  of  magnesia  in  water  containing  a  small  per- 
centage of  carbonic  acid — ^he,  however,  appears  to  give  the  preference 
to  the  first  process,  viz.,  the  infiltration  of  carbonate  of  magnesia, 
and  removal  of  lime.*  But  there  appear  to  be  one  or  two  weak 
points  about  this.  1st.  That  with  so  little  difference  in  solubility  of 
the  two  salts,  a  substitution  of  one  for  the  other  would  hardly  take 
place  to  the  extent  required.f  2nd.  That  the  lime  removed  must 
always  be  equal — proportionally  to  their  respective  atomic  weights — 
to  the  magnesia  deposited,  or  the  rock  would  increase  in  bulk.  3rd. 
That  the  result  would  only  be  a  carbonate  of  lime  with  carbonate  of 
magnesia  deposited  in  crevices  or  interspaces  left  by  the  removal  of 
the  excess  of  carbonate  of  lime ;  and  4th,  that  there  is  a  difficulty 
sometimes  in  imagining  a  sufficient .  supply  of  magnesianized  water  in 
localities  where,  as  in  the  central  plain  of  Ireland,  there  are  none  but 
limestone  rocks,  the  water  from  which,  containing  a  much  larger  quan- 
tity of  lime  than  magnesia,  could  hardly,  therefore,  produce  the  sup- 
posed effect ;  yet  all  these  limestones  are  highly  dolomitic. 

Any  alteration  that  has  taken  place  in  these  must  have  been  entirely 
produced  by  surface-water,  or  rain-water,  which  could  contain  little  or 
no  constituents  capable  of  affecting  the  limestone  rocks,  except  car- 
bonic acid.  To  the  action  of  this  agent  I  attribute  the  alteration 
which  most  of  the  Irish  limestones  have  undergone  in  their  passage  inta 
dolomite.  At  the  same  time,  I  think  it  quite  possible  that  water 
highly  charged  with  carbonate  of  magnesia,  which  may  be  the  case  if  it 
has  percolated  a  magnesian  rock,  may  deposit  the  magnesia  while  it 
removes  the  lime,  and  thus  aid  in  the  metamorphism ;  but,  as  I  shall 
show  hereafter,  waters  containing  any  appreciable  amount  of  car- 
bonate of  magnesia  are  rare;  and  slter  all,  as  Bischof  shows,  in  such  a 
case  the  chief  work  is  done  by  the  action  of  the  carbonic  acid.f 

If  we  suppose  a  limestone  rock,  containing,  as  very  many  lime- 
stones do,  carbonate  of  magnesia  to  the  extent  of  12  per  cent.,  to- 


*  Chem.  Geol.,  vol.  iii.,  p.  164. 

t  Bischof  failed,  after  *' taking  much  pains,"  to  effect  the  mutual  decomposition 
of  carbonate  of  lime  and  carbonate  of  magnesia.  In  one  case  he  digested  fragments 
of  chalk  with  pure  carbonate  of  magnesia,  for  several  years,  without  any  effect. — 
Oj?.  eit.,  vol.  iii.,  167. 

X  Chem.  Geol.,  vol.  iii.,  p.  174.  (In  effect,  although  not  in  these  precise  terms) - 


Hardman — On  the  Carboniferous  Dolomites  of  Ireland.     709 

be  objected  to  the  action  of  carbonated  water,  assuming  this  to  be 
capable  of  removing  a  greater  quantity  of  carbonate  of  lime  than  of 
carbonate  of  magnesia — in  proportion  to  thai  in  the  rock — it  is  clear 
tliat  in  the  process  of  time  we  should  have  the  percentage  of  mag- 
nesia becoming  greater  and  greater,  until  at  last  the  rock  approached 
in  chemical  composition  to  a  true  dolomite.  Moreover,  the  removal 
of  carbonate  of  Ume  would  give  rise  to  a  cavernous  or  porous  con- 
<lition  of  the  rock,  and  the  ccdcarcous  water  trickling  over  the  sides  or 
into  these  cavities  would  result  in  a  deposit  of  crystals  of  more  or  less 
pure  carbonate  of  lime  therein.  Every  one  who  has  paid  any  attention 
to  this  subject  is^  no  doubt,  aware  that  the  above  are  characteristics 
of  dolomite  limestone. 

Upon  the  above  assumption,  which  I  have  now  good  reason  to 
believe  a  certainty,  I  based  a  number  of  experiments  with  the  view  to 
ascertain  whether,  when  placed  under  conditions  as  near  as  possible 
to  those  obtaining  in  nature,  limestone  does  not  yield  more  lime  than 
magnesia,  when  submitted  to  the  action  of  carbonic  acid  in  water. 

At  the  time  I  had  not  Bischof  s  book  at  hand,  and  all  the  statements 
I  had  seen  gave  just  the  opposite  opinion.  I  was  subsequently  much 
pleased  to  find  that  Bischof  s  two  experiments*  are  confirmatory  of  my 
results,  and  they  being  unknown  to  me  then  could  have  had  no  bias- 
ing effect. 

It  is  without  exception  received,  I  believe,  that  carbonate  of  mag- 
nesia is  much  more  soluble  than  carbonate  of  lime ;  but  the  few  expe- 
riments I  have  made  on  this  point  do  not  appear  to  show  any  great 
difference ;  and  I  have  been  led  to  imagine,  therefore,  that  its  be- 
haviour in  the  presence  of  ammonia  salts  may  have  been  taken  by  some 
to  represent  its  character  under  other  circumstances.  In  the  process 
of  chemical  analysis,  when  it  is  desired  to  separate  magnesia  from 
lime,  a  little  chloride  of  ammonia  is  added  to  the  solution,  and  an 
alkaline  carbonate  then  precipitates  the  lime  with  just  a  trace  of  mag- 
nesia. If,  however,  ammonia  is  not  previously  added,  both  salts  are 
almost  instantly  precipitated  by  carbonate  of  soda. 

But,  even  admitting  that  carbonate  of  magnesia  is  per  se  a  trifle 
more  soluble  than  carbonate  of  lime,  it  is  certain  that,  when  both  are 
mingled  together  in  a  limestone  rock,  just  the  reverse  takes  place  when 
they  are  subjected  to  the  action  of  carbonated  water.  My  experi- 
ments will  show  this.  Before  proceeding  to  refer  to  them,  however,  I 
should  like  to  mention  the  restilts  obtained  by  previous  experimenters. 

Professors  W.  B.  and  R.  E.  Bogers,  at  the  Meeting  of  the  British 
Association  at  Birmingham,  in  the  year  1849,  read  a  paper  on  some 
experiments  as  to  the  solvent  power  of  carbonated  water  on  various 
minerals.!  ^  ^c  course  of  their  experiments  they  were  led  to  inves- 


*  See  pott. 

t  *'  On  the  Decompositioa  and  Partial  Solution  of  Minerals,  Rocks,  ftc.,by  pure 
▼ater,  and  water  chiu-ged  with  Carbonic  Acid."  By  Prof.  W.  B.  Rogers,  and 
Prof.  R.  E.  Rogers.     Rep.  Brit.  Assoc.  1849 ;  Tmn«.  of  Sections,  p.  40. 


710  Proceedings  of  the  Royal  Irish  Academy. 

tigate  the  comparative  solubility  of  carbonate  of  lime  and  carbonate  of 
magnesia  in  carbonated  tcater. 

The  means  which  they  employed  were — Ist,  what  they  designato 
as  the  method  with  the  tache^  consisting  in  digesting  for  a  few  minato« 
a  small  quantity  of  the  mineral,  fnely  powdered,  on  a  filter  with  car- 
bonated water,  and  then  collecting  the  filtrate  and  examining  it  for 
lime  and  magnesia.  2nd.  By  agitating  briskly  for  some  time,  in  a  large 
glass  bottle  containing  carbonated  water,  a  quantity  of  the  mineral,  in 
this  case  slsofnely  powdered.  The  water  was  then  evaporated,  and  the 
residue  examined.  In  both  these  cases,  magnesian  limestone  so  treated 
yielded  a  larger  quantity  of  carbonate  of  magnesia  than  of  carbonate 
of  lime,  proportional  to  their  relative  amounts  in  the  rock ;  and  the 
Professors  Rogers  infer  that  in  nature  this  process  would  result  in  thi' 
limestone  becoming  less  magnesian,  instead  of  approaching  to  a  dolomite, 
as  is  generally  maintained. 

Now  I  wish  to  point  out  that  the  process  sketched  above  cannot 
by  any  means  be  held  to  represent  that  which  takes  place  in  nature. 
The  very  act  of  powdering  the  dolomitic  limestone  has  destroyed  any 
value  the  experiment  might  otherwise  have  had.  "We  do  not  find  rocks 
in  situ  thus  prepared  for  the  invading  action  of  carbonic  acid ;  and  we 
know  that  dolomites  entirely,  and  magnesian  limestones  to  a  great 
extent,  resist  the  action  of  much  stronger  acids  than  a  merely  cm- 
bonated  solution,  so  long  as  they  remain  solid ;  but  once  they  are 
powdered  up,  they  are  readily  dissolved  with  evolution  of  carbonic 
acid.  In  eftect,  this  fact  is  made  use  of  in  testing  rocks  in  the  field ; 
dolomitic  limestone  being  scarcely  affected  at  all  by  moderately  diluU? 
hydrochloric  acid,  and  can  therefore  be  readily  distinguished  from 
ordinary  limestone. 

I  do  not  know  if  the  amount  of  magnesium  carbonate  obtained  by 
the  above  method  was  quantitatively  determined  by  Professors  Rogers, 
as  I  have  not  been  able  to  consult  their  detailed  paper  in  the  Ameri- 
can Journal  of  Science ;  but  it  is  curious  that  Bischof  obtained  just 
the  contrary  result  to  tieirs,  in  the  two  experiments  I  have  already 
referred  to,  although  his  method  of  proceeding  is  essentially  the  same. 
His  results  agree  very  well  with  my  own. 

Bischof*  s  Experiments,  The  composition  of  the  limestone  being  as- 
certained, a  portion  was  powdered  finely,  and  placed  in  water  for  24 
hours.  The  water  was  then  examined,  and  proved  in  the  cases  tried 
to  contain  either  no  trace,  or  a  very  small  one,  of  magnesia.  I  shall 
copy  one  of  these  for  example,  as  it  will  be  useful  to  compare  with  my 
results. 


H\RDMAN — On  the  Carboniferom  Dolomites  of  Ireland.     711 

I^Iack  Magnesian  Litnestone.     From  Stadtbergen.* 

I.  Analysis. 

Carbonate  of  lime, 84- 57 

,,            magnesia, 11 '04 

„             iron, 1*15 

Silica  and  carbon, 1*36 


98-62 


II.  Akouxt  of  Constituents  dissolted  in  24  hours^  from  6660  grains. 

Grains. 

Carbonate  of  lime, 4*29 

Carbonate  of  magnesia, no  trace. 

There  appears  to  be,  for  the  quantity  taken,  and  the  time  occupied, 
more  carbonate  of  lime  dissolved  than  occurred  in  any  of  my  experi- 
ments ;  however  the  powdering  of  the  rock  might  give  rise  to  this. 
But  this  important  fact  still  remains,  that,  when  treated  with  a  weak 
solution  of  carbonic  acid,  limestone  yields  more  carbonate  of  lime  pro- 
poi-tionally  than  carbonate  of  magnesia. 

Perhaps  it  is  well  to  notice  here  the  curious  difference  that  pres- 
sure makes,  not  only  in  the  solvent  power  of  carbonic  acid,  which 
is  increased,  but  in  its  relative  effects  on  the  two  carbonates.  It 
appears  certain  that,  under  the  ordinary  atmospheric  pressure,  and  in 
such  proportions  as  it  occurs  in  most  surface  or  even  underground 
waters,  it  will  chiefly  attack  the  lime,  while  under  a  high  pressure, 
and  in  large  quantity  it  seems  to  confine  its  attentions,  I  may  say, 
strictly  to  the  magnesia.  Advantage  has  actually  been  taken  of  this 
property  to  procure  salts  of  magnesia,  such  as  the  sulphate,  from 
dolomite;  the  process  consisting  in  submitting  the  rock,  finely 
ground,  with  water,  to  the  action  of  carbonic  acid,  under  a  pressure  of 
about  four  atmospheres.  It  is  then  found  that  nearly  all  the  carbonate 
of  magnesia  is  removed,  without  admixture  of  carbonate  of  lime.f 

This  is  worth  noting,  as  it  may  serve  to  account  for  the  large 
quantities  of  carbonate  of  magnesia  which  are  occasionally,  hut  not 
often^  found  in  spring  waters ;  and  may  also  explain  the  production  of 
deep-seated  dolomites  by  infiltration  of  magnesian  water. 

As  it  is,  however,  with  dolomites  formed  under  circumstances  not 
taking  in  the  element  of  pressure  we  shall  have  to  deal  at  present, 
I  shall  not  enter  more  fully  into  the  above  matter  just  now ;  but  pro- 
ceed to  describe  the  experiments  I  have  referred  to. 

It  appeared  to  me  that  if  it  could  be  proved  by  some  process  as 

*  Bischof,  op.  eit.,  vol.  iii.,  p.  196. 

t  Dingl.  Polyt  J.,  ccix.,  467. —-4**.  Jour.  Chem.  Soc.,  vol.  xii.,  p.  96. 


712  Proceedings  of  the  Royal  Irish  Academy. 

nearly  as  possible  akin  to  that  which  goes  on  in  nature,  that  more" 
carbonate  of  lime  is  dissolved  than  carbonate  of  magnesia  by  a  weakly 
carbonated  solution,  it  would  go  far  towards  solving  the  question,  as 
to  the  formation  of  some  dolomites. 

The  process  I  adopted  was  very  simple.  A  limestone  was  selected 
which  contained  a  fair  percentage  of  magnesia,  it  was  analysed,  and 
the  proportions  noted.  A  portion  of  the  rock  was  then  broken  up  into 
small  fragments,  somewhat  less  than  half-an-inch  across.  These  were 
placed  in  a  jar  open  to  the  atmosphere,  with  distilled  water,  and  car- 
bonic acid  was  passed  in.  A  piece  of  litmus  paper  was  placed  in  the 
jar,  and  the  flow  of  gas  was  stopped  as  soon  as  this  became  reddened. 
Whenever  the  paper  showed  any  indication  of  returning  to  its  original 
tint,  the  solution  was  again  saturated  with  the  acid,  and  so  on.  In  this 
way  an  over  saturation  with  acid  (which  might  have  had  too  energetic 
an  effect  on  the  rock)  was  prevented,  and  the  whole  experiment  brought 
as  near  to  nature  as  is  possible  in  a  laboratory,  in  having  a  mildly  car- 
bonated solution  acting  on  surfaces  of  the  rock,  and  not  on  minuto 
particles. 

With  the  process  carried  on  in  this  manner,  I  found  the  action  of 
the  carbonic  acid  to  be  extremely  slow,  compared  with  the  results  ob- 
tained from  powdered  rock  by  other  experimenters,  several  days  being 
required  to  dissolve  sufficient  of  the  carbonates  for  estimation ;  but  in 
every  case  the  carbonate  of  lime  was  much  in  excess.  Some  of  my 
experiments  were  merely  tentative,  and  are  not  worth  recording ;  but 
I  ^all  now  mention  the  details  of  some  of  the  more  important  ones. 

No.  I. — Limestone  from  the  interior  of  the  Cave  of  Dunmore,  Co.. 
Kilkenny.     A  light  grey  compact  magnesian  limestone. 

Analysis. 

Mean  of  two  specimens. 

Carbonate  of  lime, 68-21 

Carbonate  of  magncsiu, 24-00 

Peroxide  of  iron,  .     .      i  .^^ 
,,           alumina,       J       •     •     .     . 

Silica, 1-92 

Carbonate  of  iron, 0-90 


99-35 


It  will  be  observed  that  this  is  a  remarkably  pure  limestone,  the^ 
amount  of  silicates,  &c.,  being  very  small.  The  rock  is  evidently  be- 
coming dolomitic,  for  the  limestone  above  and  around  the  cave  is  not 
by  any  means  highly  magnesian. 

£xp,  1. — ^A  quantity  of  the  limestone  was  broken  up  small.  110 
grains  were  taken  and  placed  in  a  jar  with  distilled  water,  and  car- 
bonic acid  gas  was  passed  in  almost  continuously  for  72  hours.     At 


Hardman. — On  the  Carboniferous  Dolomites  of  Ireland,     713 

the  expiration  of  that  time  the  solution  was  carefully  filtered  off  and 
examined.  It  contained  both  carbonate  of  lime  and  of  magnesia,  but 
in  extremely  small  quantity,  viz. : — 

Carbonate  of  Hme,      ....     0*05  grains. 
Carbonate  of  magnesia,    .     .     .     0  007     „ 

Calculated  now  according  to  the  percentage  of  carbonate  of  lime 
in  the  rock,  t.  tf.,  68-21,  the  above  gives  the  respective  proportions  dis- 
solved to  be — 

Carbonate  of  lime,  .     .  .     68-21 

„  magnesia,     .     .     .       9*32  only, 

or  less  than  half  the  proportion  of  carbonate  of  magnesia  actually  in 
the  rock.  It  is  clear,  therefore,  that  this  operation,  continued  suffi- 
ciently long,  must  result  in  a  dolomite. 

JEr^.  2. — About  the  same  quantity  of  the  Dunmore  limestone  was 
taken — 110  grains,  and  placed  in  a  jar  with  water  as  before.  Carbonic 
acid  gas  was  then  passed  in,  nearly  continuously  for  44  days.  For 
about  a  week  or  so  of  that  time  no  gas  was  passed  in,  but  for  the  most 
part  of  this  experiment  the  water  was  supersaturated  with  the  acid, 
the  result  of  which  will  be  presently  seen. 

The  liquid,  having  been  carefully  filtered  off,  evaporated  to  dryness,, 
and  the  residue  examined  yielded  the  following  result : — 

Carbonate  of  lime, 104  grains. 

,,           magnesia,     .     .     .     0-306     „ 
„  iron, a  trace. 


Total  dissolved,  .     .     1-346 

Calculating  again  according  to  the  proportion  of  carbonate  of  lime 
in  the  rock,  we  have — 

Carbonate  of  lime, 68-21 

„  magnesia, 20'06 

I  attribute  the  high  percentage  of  magnesia  carbonate  dissolved  in 
this  instance  to  the  supersaturated  condition  of  the  carbonic  acid  solu- 
tion, which  was  allowed  to  become  quite  in  excess  of  anything  that 
could  occur  in  nature.  Nevertheless,  it  is  evident  that  the  carbonate 
of  lime  was  the  most  rapidly  dissolved  in  this  case  also. 

It  seems  remarkable  also  that  so  small  a  portion  of  the  limestone 
was  dissolved  after  such  long  continued  action.  However,  this  was 
confirmed  in  other  experiments,  and  I  apprehend  it  is  due  to  the  mag- 
nosian  character  of  this  rock.  It  is  certain  that  the  action  of  small 
quantities  of  carbonic  acid  on  limestones  is  in  an  inverse  ratio  to  th& 


714  Proceedings  of  the  Royal  Irish  Academy. 

amount  of  magnesia  in  them — dolomites  being  almost  unassailable. 
Experiments  4  and  5  will  show  how  well  this  is  borne  out. 

Exp,  8. — As  the  limestone  used  in  the  last  was  hardly  dixninished 
at  all,  it  was  again  covered  with  distilled  water,  and  carbonic  acid 
passed  in.  Care  was  taken  to  keep  the  solution  just  slightly  acid,  and 
to  avoid  the  error  of  Experiment  2.  The  action  was  continued  for  20 
days.  The  solution  was  then  filtered  off,  evaporated,  and  examined  as 
before,  with  the  following  result : — 

Carbonate  of  lime,       ....     0*55  grains. 
„  magnesia,     .     .     .     0*07      ,, 

,,  iron,  .....    a  trace. 


Total  dissolved,     .     .     062 

This  experiment  bears  out  the  second  very  well,  as  to  the  toUl 
fjuantity  of  substance  dissolved,  the  time  occupied  being  half  of  that, 
and  the  total  dissolved  about  half  also.  The  proportion  of  magnesia  i< 
less,  however,  no  doubt  owing  to  the  precaution  of  using  a  weak  solu- 
tion of  acid.     The  proportion  calculated  as  before  would  give — 

Carbonate  of  lime, 68'21 

,,  magnesia,    .     .     .       9*04 

This  agrees  almost  exactly  with  the  proportions  determined  in 
Experiment  1. 

No.  II. — Limestone  from  the  breccia  of  the  roof  of  the  Shandon  Cave, 
Dungarvan,  Co.  Waterford.  A  bluish-grey  fossiliferous  limestone, 
apparently  not  very  magnesian.  It  turns  out,  however,  to  contain 
a  rather  large  proportion  of  carbonate  of  magnesia. 


AXALYSIS. 


79-89 
12-71 
trace. 


Carbonate  of  lime, 

,,  magnesia, 

,,  iron,  .     . 

Peroxide  of  iron,  .  . 
Alumina,  .... 
Silica  and  insoluble  residue,  3*40 


I    408 


10000 


Exp,  A. — 187  grains  of  the  limestone,  broken  in  small  pieces  a^ 
before,  were  placed  in  a  large  jar  with  distilled  water,*  and  carbonic 

*  It  should  be  noted  that  in  all  the  experiments  except  No.  1,  the  same  quan- 
tity of  water  was  used,  vix.,  about  20  02. ;  care  being  taken  to  supply  loss  by 
evaporation. 


Hardman — On  the  Carboniferous  Dolomites  of  Ireland.      715 

acid  passed  in :  stipersaturation  with  the  acid  was  gaarded  against, 
jind  the  limestone  was  allowed  to  remain  in  the  water  for  40  days. 
The  liquid  was  then  examined,  and  it  yielded  : — 

Carhonate  of  lime 3-59  grains. 

,,            mnpiR'sia,     .     .         .     .     0*47       ,, 
„  iron, trace. 


406 


This,  calculated  according  to  the  percentage  of  carbonate  of  lime  in 
the  rock,  would  give  for  the  proportions  dissolved  : — 

Carbonate  of  lime, 79*89 

„  magnesiu, 9*34 

89-23 ; 

there  being  in  the  rock  as  much  as  12*71  of  carbonate  of  magnesia : 
so  that  in  this  case  also  it  will  bo  seen  that  the  result  must  be  a 
gradual  increase  in  the  amount  of  that  constituent. 

It  will  be  noticed  also,  that  although  the  experiment  was  not  con- 
tinued for  quite  so  long  a  period  as  No.  2,  the  total  amount  of  car- 
bonates dissolved  is  more  than  double. 

JExp,  5. — The  fragments  of  limestone  from  Shandon,  used  in  the 
last  experiment,  were  subjected  to  the  further  action  of  carbonic 
acid,  in  the  same  way,  the  action  being  allowed  to  go  on  for  20 
days.     The  solution  being  then  examined  yielded  the  following : — 

Carbonate  of  lime, 1-15  grains. 

„  magnesia, 0-11       ,, 

„  iron, a  trace. 

Total  dissolved,     .     .     1-26 

Calculated  as  before,  the  percentage  dissolved  will  be  in  the  pro- 
portion— 

Carbonate  of  lime, 79*89 

,,  magnesia, 7-64 

87-53, 

a  result  sufficiently  near  that  of  the  former  experiment.     The  total 

amount  dissolved  in  this  case  is  not  quite  half  that  dissolved  in  double 

the  time  in  the  former  experiment. 

These  investigations  prove  the  following  points  : — 

1°.  That  in  a  weak  solution  of  carbonic  acid,  limestones  in  the 

mass,  not  powdered,  yield  more  carbonate  of  lime  than  of  magnesia. 


716  Proceedings  of  the  Royal  Irish  Academy, 

2^.  That  in  equal  times  the  more  magnesian  limestones  are  least 
susceptible  to  the  action  of  such  a  carbonic  acid  solution. 

3^.  That  other  things  being  equal,  the  relative  proportion  of  the 
two  bodies  dissolved  appears  to  remain  fairly  unaffected  by  the  time 
occupied  in  the  experiment. 

I  should  mention  that  the  experiments  detailed  above  are  not  the 
only  ones  made  which  verified  the  above  points:  but  it  would  be 
tedious  and  uninteresting,  I  conceive,  to  enter  into  particulars  of  all 
of  them. 

[Note  added  in  Press, — In  order  to  test  the  effect  of  more  enei^tic 
Acids,  the  following  experiment  was  made  since  the  foregoing  was 
written. 

A  piece  of  dolomite  from  Ballyfoyle,  near  Kilkenny,  having  the 
following  composition,  was  taken : — 

ANALYSIS. 

Carbonate  of  lime, 55'48 

„            magnesia, 43*62 

Ferric  oxide  and  alumina,     .     .     .     .  0*68 

Silica,  &c., 0-34 


10002 
Specific  Gravity,  2-73. 

Being  broken  up  small,  pieces  were  carefully  selected,  so  as  to  be 
as  free  as  possible  from  other  minerals,  such  as  carbonate  of  iron, 
calcite,  &c.  141  grains  were  placed  in  a  beaker  with  distilled  water, 
to  which  a  little  hydrochloric  acid  was  added.  The  solution,  although 
weak,  caused  copious  effervescence  from  the  interstices.  The  experi- 
ment was  continued  for  about  a  month — a  few  drops  of  acid  being 
added,  when  test-paper  denoted  that  the  acid  previously  added  had 
been  neutralised.  Having  left  home  for  a  fortnight,  I  found  on  my 
return  that  a  flocculent  precipitate — ^probably  carbonates  of  iron  and 
lime — had  been  thrown  down,  no  doubt  induced  by  absorption  of  car- 
bonic acid  from  the  air.  The  addition  of  a  few  drops  of  acid  dissolved 
this.  The  whole  was  then  allowed  to  stand  for  more  than  another 
month;  at  the  expiration  of  which  time  a  little  acid  was  added  to 
dissolve  the  precipitate  that  had  again  formed — ^but  not  enough  to 
affect  the  undissolved  dolomite — and  the  solution  was  filtered  off. 
Both  solution  and  undissolved  residue  were  then  carefully  analysed. 

The  following  Table  gives  the  result : — 


Hardman — On  the  Carboniferous  Dolomites  of  Ireland.     717 


1        1.        '       II. 

,  In  undissolved      y-  c^i ..«:/>« 
1       Residue.       ,   ^°  Solution. 

III. 
Total. 

Carbonate  of  lime,      .     . 

„        „  magnesia,    . 

Ferric  oxide  and  alumina, 

Insoluble  residue   (silica, 

&c.), 

Grains. 

38-50 

31-25 

0-63 

0-48 

Grains. 

40-10 

29-65 

0-33 

Grains. 

78-60 

60-90 

0-96 

0-48 

70-86 
d  to  Percefitt 

7008 

140-94 

The  above  reduce 

ige  Composition. 

Carbonate  of  lime,      .     . 

„       „  uiagnesia,  - 

Ferric  oxide  and  alumina, 

Insoluble  reeidue,  .     .     . 

54-33 

44  10 

0-88 

0-67 

57-22 

42-31 

047 

65-76 

43-20 

0-68 

0-34 

99-98 

100-00 

99-98 

So  far  from  the  carbonate  of  magnesia  being  the  moat  soluble  here, 
it  will  be  seen  that  the  result  of  the  experiment  has  been  actually  to 
bring  the  composition  of  the  magnesian  limestone  nearer  to  that  of 
true  dolomite  than  it  was  before.  The  proper  proportions  being 
about  6208,  Ca  CO3  to  46-50,  Mg  CO3.  It  will  also  be  observed 
from  column  II.  that  the  carbonate  of  lime  dissolved  was  much  in 
excess  of  carbonate  of  magnesia.] 

It  had,  some  time  before,  struck  me  that  if  magnesian  carbonate 
were  really  more  soluble  under  the  circumstances  which  occur  in 
nature  than  carbonate  of  lime,  we  ought  to  find  some  account  of  it  in 
the  stalactites  and  stalagmites  so  invariably  found  where  water  has 
percolated  through  limestones.  It  has  been  long  known  that  these 
accumulations  are  usually  free  from  magnesia,  and  the  Messrs. 
Kogers,  in  the  paper  already  cited,  refer  to  this  as  a  proof  of  the 
greater  solubility  of  the  carbonate  of  magnesia,  since  they  say  the 
latter  is  carried  off  in  solution,  while  the  carbonate  of  lime  is  depo- 
sited.* Now  it  is  difficult  to  imagine  that  all  the  carbonate  of  mag- 
nesia would  so  completely  disappear,  and  one  would  rather  suppose 


*  Biscbof ,  in  describing  tbe  mode  of  formation  of  the  sprudelstone  from  the 
Carlsbad  bot  springs,  appears  to  coincide  witb  this  opinion,  since  he  considers  the 
magnesia  to  be  carried  away  wholly  in  solution.  In  this  case,  however,  the  water 
has  a  ready  means  of  escape,  and  the  deposition  of  carbonate  of  lime  is  due  to 
lose  of  carbonic  acid,  and  not  to  evaporation. 


718  Proceedings  of  the  Royal  Irish  Academy. 

the  possibility  of  a  few  layers  of  it  in  stalactites,  had  it  ever  been  held 
largely  in  solution.  At  any  rate,  the  drippings,  which  would  under 
i^uch  a  supposition  be  charged  with  carbonate  of  magnesia,  falling  on 
the  floor,  say  of  a  cave,  if  they  produced  any  stalagmite,  should  pro- 
duce a  magnesian  one,  or  one  containing  a  very  considerable  propor- 
tion of  that  body.  It  appears,  however,  that  neither  the  one  nor  the 
other  contains  any  appreciable  amount  of  it  at  all,  and  even  those 
from  magnesian  limestones  follow  the  general  rule.  I  can  hardly 
think  that,  in  the  case  of  stalagmites,  some  of  the  magnesian  carbonate, 
if  it  had  been  present  in  the  solution  which  formed  them,  would  not 
remain.  It  ought,  certainly,  to  be  found  in  the  upper  layers,  as  sta- 
lagmite is  by  no  means  porous,  but  this  seems  not  to  be  so.  I  am 
speaking  now  of  stalagmite  formed  in  places  where  the  water  could 
have  had  no  ready  means  of  escape  except  evaporation. 

On  the  other  hand,  the  argument  as  to  the  most  soluble  being 
carried  away  entirely  ought  to  hold  good  as  respects  the  carbonates  of 
lime  and  iron.  As  tie  latter  is  least  soluble  of  all,  whenever  it  occurs^ 
in  stalactites  they  should  consist  nearly  entirely  of  it,  if  the  above 
idea  were  correct.  A  great  amount  of  the  more  soluble  lime-salt 
would  be  carried  off  while  the  carbonate  of  iron  was  crystallising, 
and  we  would  have  stalactites  containing  usually  a  very  large  per- 
centage of  iron ;  but  this  is  rarely  the  case. 

As  analyses  of  stalactitic  bodies  are  not  numerous,  I  give  those  of 
two  or  three  which  I  .have  examined. 

No.  I. — Stalagmite — from  the  floor  of  Dunmore  Cave,  Co.  Kil- 
kenny. 

A  part  of  the  upper  layers  where  the  thickness  was  at  least 
6  inches. 

AjfALTSIS. 

Carbonate  of  lime, 97*12 

,,              magnesia 0*79 

,,             iron, r86 

Peroxide  of  iron,  alumiun,    .     ...  0*23 


10000 


This  stalagmite  was  of  a  dirty  grey  colour,  and  apparently  full  of 
impurities. 

No.  II. — Stalagmite  from  roof  breccia  of  the  Shandon  Cave,  Dun- 
garvan  : — 

This  stalagmite  forms  an  extremely  pretty  mass,  of  a  clear  cream- 
colour,  and  is  well  crystallized.  It  occurs  in  large  quantity,  and  often 
in  considerable  masses  amongst  and  underneath  the  breccia.  The  spe- 
cimens examined  adhered  to  the  under  side  of  the  limestone,  a  portion 
of  which  was  analysed  and  experimented  on.  (See  Experiments 
4  and  5.)  It  is  therefore  reasonable  to  suppose  that  its  materials 
were  derived  from  that  very  magnesian  rock. 


Hakdman — On  the  Carboniferoua  Dolomites  of  Ireland.    719 


AKALT8I8. 

Carbonate  of  lime, 99*25 

„            magnesia, 0*70 

ff            iron,            trace 


99-95 


The  iron  present  was  hardly  sufficient  to  give  the  pale  yellow 
colour  to  the  mass.  The  parent  rock  of  these  stalagmites  being  so 
very  magnesian,  we  should  expect  to  find  a  very  appreciable  amount 
of  magnesia  in  them  if,  as  is  thought  by  so  many,  the  carbonate  of 
magnesia  in  limestone  rocks  is  so  very  soluble.  But  what  can  have 
become  of  it  ?  for  I  shall  show  presently  that  the  waters  of  limestone 
districts  contain  a  very  trifling  amount  of  magnesia. 

It  is  hardly  conceivable  l£at,  were  the  carbonate  of  magnesia  in 
such  rocks  the  most  soluble  in  weak  carbonic  acid,  there  should  be 
barely  traces  of  it  in  these  deposits ;  and  from  this  circumstance,  as  well 
as  from  its  scarcity  in  spring  waters,  we  should  rather  be  led  to  infer 
its  greater  insolubility,  even  without  the  experiments  I  have  brought 
forward. 

No.  III. — Stalactites  from  a  highly  magnesian  limestone,  Bailway 
bridge,  Thomastown,  Co.  Kilkenny. 

Analysis. 

Carbonate  of  lime, 99*25 

„  magnesia, 0*50 


99.75 


One  link  in  the  chain  is  still  wanting,  viz.,  the  analysis  of  waters 
which  have  undoubtedly  passed  through  such  limestones  as  the  above- 
mentioned,  and  which  have  deposited  stalactitic  matter.  Some  infor- 
mation on  this  point  I  hope  to  have  a  future  opportunity  of  conve3dng 
to  the  Academy,  as  I  have  commenced  some  analyses  of  the  waters 
which  have  dripped  from  the  roof  of  the  Cave  of  Dunmore.  But  I 
am  compelled  for  the  present  to  fall  back  on  the  accounts  of  various 
waters  already  published  by  different  authors. 

In  Dr.  Sterry  Hunt's  paper  on  the  Chemistry  of  Natural  Waters,* 
a  series  of  nineteen  analyses  of  various  American  waters  is  given,  in  five 
of  which  carbonate  of  lune  is  much  in  excess  of  carbonate  of  magnesia, 
and  in  some  others  chloride  of  calcium  is  in  very  large  proportion  to 
that  of  magnesia.    In  the  remainder,  however,  the  amount  of  carbon- 


&.  I 


•  Op,  cit,,  p.  92,  et  teq. 
A.  ntoc,  8S&.  n.,  VOL.  ii.,  science.  3  U 


720  Proceedings  of  the  Royal  Irish  Academy. 

ate  of  lime  and  of  carbonate  of  magnesia  is  about  equal.  These  aie 
the  only  analyses  of  water  I  have  seen  in  which  the  amount  of  mag- 
nesian  salts  at  all  approaches  that  of  the  lime  salts. 

In  the  valuable  abstracts  of  chemico-mineralogical  papers  pub- 
lished in  the  Journal  of  the  Chemical  Society,  from  vol.  ix.  to  vol. 
liv.,  inclusive,  I  find  very  many  analyses  of  mineral  waters,  with  one 
or  two  exceptions  European,  ordinary  river  water,  chalybeate  and 
thermal  springs,  &c.  In  all  of  these  the  carbonate  of  lime  is  in  great 
excess  of  that  of  magnesia ;  the  chlorides  also  occupy  the  same  relative 
position.  In  all  these  analyses  there  is  no  instance  to  the  contrary. 
The  proportions  are  very  variable  of  course,  in  some  cases  carbonate 
of  magnesia  being  altogether  absent.  The  lowest  proportion  in  which 
it  is  stated  in  any  of  these  is  * 

Carbonate  of  lime, 145 

„  magnesia, 7 

The  highest  is,t  for  total  lime  and  magnesia  salts :  they  are  cal- 
culated only  as  oxides — 

Lime(CaO.) 7494 

Magnesia  (MgO.)        20*54 

and  the  average  proportion  appears  to  be  about  14  to  1. 

About  thirty  or  forty  analyses  are  included  in  the  above  resumi.  In 
no  single  instance  v^as  carbonate  of  magnesia  in  excess  of  carbonate 
of  lime.  All  these  scattered  analyses  are  the  more  valuable  in  their 
agreement  on  the  point  I  am  urging,  from  their  authors  having,  appa- 
rently, no  particular  theory  to  bring  forward,  and,  though  ^en  at 
random,  the  persistence  in  the  larger  amount  of  lime  salts  is  very 
marked.  I  may  now  refer  to  the  capital  table  of  analyses  of  river 
waters  given  by  Bischof,}  which  includes  forty-eight  examples,  in 
every  one  of  which  carbonate  of  lime  is  very  largely  in  excess  of  tliat 
of  magnesia.    These  range  as  follows : — 

Carbonate  of  lime,      .     .     1-28  to  18-23  )  In  100,000 
yf  magnesia,  .    0*09  to     1*47  (      parts. 

In  many  cases  no  carbonate  of  magnesia  is  recorded  at  all,  even 
where  the  corresponding  lime  salt  is  so  high  as  26*2,  nor  is  there  in 
any  case  a  large  proportion  of  the  more  soluble  salts  of  magnesia,  sul- 
phate, or  chloride.    This  shows,  therefore,  that  carbonate  of  magnesia 


*  Chalybeate  spring  at  Sellafield,  near  Whitehaven.  W.  H.  Watson,  Chem. 
News,  zzzii.,  p.  11.    Abt.  Jour.  Chem.  Soc.,  vol.  xiii.,  p.  1169. 

t  Rhine  water,  near  Kdln,  Dr.  Yohl.  Abt,  Jour.  Chem.  Soo.,  vol.  ix., 
PP.213-U. 

J  Op.  eit.  i,  pp.  76,  77. 


Hardman — On  the  Carboniferam  Dolomites  of  Ireland.    721 

is  nowhere  so  abundant  in  surface-waters  as  some  writers  on  this 
subject  apparently  consider,  and  that  wo  are  justified  in  rejecting 
the  statement  that  most  dolomites  are  formed  by  infiltration  of  mag- 
nesian  water,  at  least  until  more  evidence  on  that  head  is  produced. 

It  would  appear,  in  fact,  to  be  more  reasonable  to  assume  that  the 
lime  in  limestone  rocks  was  conveyed  into  them  by  percolation 
of  mineral  waters,  than  that  the  magnesia  of  dolomitic  rocks  so 
originated. 

A  very  important  paper  bearing  on  this  subject,  and  perhaps  tho 
only  one  in  which  it  has  yet  been  definitely  treated,  is  that  of  E. 
T.  Gk>rup-Besanez,  on  the  Dolomite  Springs  of  the  Jura.*  The  author 
gives  a  series  of  analyses  of  waters  of  springs  rising  in  the  Jura,  many 
of  them  in  the  neighbourhood  of,  or  as  it  would  appear,  actually  rising 
from,  dolomitic  limestones ;  and  he  finds  that  in  some  cases  the  car- 
T)onate  of  lime,  and  of  magnesia,  are  actually  present  in  dolomitic  pro- 
portions.    Por  instance,  two  springs  give  the  following — 

I.  II. 

CaCO,,       .     .     .     r,7-32      I      57-21  f 
MgCOj,     .     .     .     42-68      I      42-79 

This  is  very  remarkable  indeed. 

Some  of  the  analyses  gave,  however,  the  following : — 

CaCO,,        ....     88      I      89      I      70      I      68 
Mg  CO,,       ....     12      I      11      I      30      I      32 

and  the  mean  of  the  analyses  was — 

CaCOj, 53-71 

MgCO,, 14-29 

The  author  is  led  to  agree,  therefore,  with  Bischof  in  the  opinion 
that,  from  perfectly  formed  dolamttei,  water  containing  carbonic  acid 
dissolves  out  Ca  Coj  and  Mg  Cqs  together  in  fixed  proportions,  J  but 
does  not  coincide  with  him  in  the  idea  that  the  presence  of  magnesite 
in  cavities  of  the  magnesian  limestone  prove  the  dolomite  to  be  a  per- 
fectly formed  one,§  since  crystalline  magnesite  would  not  be  deposited 
from  such  solutions.  He  considers  the  geological  formation  of  dolo- 
mite a  subject  yet  quite  unsettled,  and  is  opposed  to  Bischof  s  admission 


•  Ann.  ChenuFhorm.  Suppl.  Band.yiii.,  230-242.  Abe,  Jour.  Chem.  Soc.,toI. 
X.,  p.  69. 

t  In  all  the  analyses,  other  constitnents  proved  too  trifling  for  notice. 
X  See  Bischof,  Chem.  Oeol.  iii.,  p.  196. 
9  See  Bischof,  op,  eit,,  iii.,  p.  196. 

3U2 


722  Proceedings  of  the  Royal  Irish  Academy. 

that  carbonated  water  may  dissolve  out  only  carbonate  of  lime  until, 
at  last,  the  proper  dolomitic  proportions  are  reached.* 

It  will  be  noticed,  however,  that  in  the  analyses  given  in  the  paper 
just  referred  to,  there  is  after  all,  in  most  of  them,  a  considerable 
range  of  proportion  outside  the  dolomitic  limit*  and  the  mean  given  of 
all  tbe  analyses  shows  that,  in  most  cases,  the  magnesian  carbonate 
cannot  have  been  present  to  an  extent  oE  more  than  14  or  15  per  cent., 
and  that  in  all,  it  is  much  less  than  the  lime  carbonate — ^thus  com- 
pletely verifying  my  experiments,  and  showing  that  those  of  Professor 
Bogers  are  not  based  on  natural  processes.! 

I  think,  on  che  whole,  it  might  be  safely  asserted  that  in  every 
case  where  atmospheric  water  acts  on  a  limestone  rock,  it  will  remove 
proportionately  more  carbonate  of  lime  than  carbonate  of  magnesia. 
The  reason  for  this  it  would  be  difficult  to  give,  seeing  that  there  can 
be  no  doubt  as  to  the  somewhat  greater  solubility  of  magnesian  salts 
under  laboratory  conditions. 

If  we  suppose,  however,  that  the  carbonate  of  magnesia,  in  what- 
ever proportion  it  is  present  in  the  rock,  is  origindly  combined  as 
dolomite f  it  might  account  for  what  otherwise  appears  to  be  an  ano- 
maly. Is  there  any  diffictilty  in  supposing  that  the  small  amount  of 
magnesian  carbonate  which  it  is  known  many  corals  and  moUuscan 
shells  contain,  sometimes  reaching  as  much  as  7*6  per  cent,  may 
have  been  secreted  as  dolomite  ? 

Forchammer  has  shown  that  some  corals,  annelids,  and  molluscan 
shells,  contain  an  appreciable  quantity  of  carbonate  of  magnesia;  in  the 
annelids  especially  it  being  very  high  (7*6  percent.)  Bischof,  com- 
menting on  this  fact,  remarks,  the  limestones  formed  by  serpuUe, 
eoraUium,  isis,  and  probably  other  genera,  ought  to  be  termed  dolo- 
mitic limestone.  J 

It  is  possible  that  many  other  organisms,  such  as  build  up  rocks^ 
secrete  carbonate  of  magnesia  to  a  perceptible  amount.  Many  plants 
also  secrete  carbonate  of  magnesia,  and  it  is  just  possible  that  in  such 
cases  the  carbonate  of  lime  and  of  magnesia  may  be  combined  as  dolo- 
mite. In  such  an  event  the  removal  of  the  excess  of  carbonate  of  lime, 
which  might  in  these  instances  be  regarded  as  a  matrix,  would  soon 
result  in  a  dolomite. 

It  cannot  be  said  that  the  foregoing  analyses  of  waters  prove  much 
with  regard  to  the  relative  solubility  of  the  carbonates,  since  we  havo^ 


•  See  BiBchof,  op,  cit.  iii.,  pp.  162, 196, 200,  203,  &c.  Biscbof  does  not,  how- 
ever, entirely  favour  this  theory,  which  is  Orandjean's,  not  his  own,  but  allows 
merely  that  such  a  process  is  possible  in  some  cases. 

t  Bischof  asserts  that  even  springs  rising  in  dolomite  must  always  contain 
more  carbonate  of  lime  than  of  magnesia,  as,  from  his  experiments,  carbonated 
water  extracts  little  or  no  carbonated^  magnesia  from  dolomitic  rocks^op.  eit,,  vol. 
L,  p.  81. 

X  Bischof,  op,  cit.,  vo\  i.,  p.  183;  vol.  ii.,  pp.  48,  49. 


Hardman — On  the  Carboniferous  Dohmitea  of  Ireland.    723 

in  few  instances  any  information  as  to  the  composition  of  the  rocks 
over  or  through  which  they  passed ;  and  these  rocks  may  have  con- 
tained but  a  trace  of  magnesia.  But  we  can  assert  this  much ;  that 
on  the  generally  received  notion  as  to  the  relative  solvency  of  those 
bodies,  and  with  which,  save  in  the  event  of  their  being  combined  in 
rocks — ^when  it  certainly  seems  to  reverse  its  behaviour — I  must  coin- 
•cidc,  the  result  of  such  waters  percolating  through  rocks  would  be,  if 
anything,  to  form  limestone,  and  not  dolomite,  since  the  carbonate  of 
lime  being  more  abundant,  as  well  as  less  soluble  than  the  carbonate 
of  magnesia,  would  be  more  likely  to  be  deposited.  In  all  these  sup- 
posed infiltration  theories  too,  the  bulk  of  the  rock  would  necessarily 
be  increased,  unless  it  is  taken  for  granted  that  some  of  the  carbonate 
of  lime  is  removed  in  the  process,  and  replaced  by  carbonate  of  mag- 
nesia. 

The  only  way  in  which  the  production  of  at  least  the  Irish  dolo- 
mites can  be  accounted  for  is,  by  the  gradual  removal  of  the  excess  of 
-carbonate  of  lime.  It  is  quite  possible,  and  indeed  likely,  that  in 
svLch  a  process,  as  the  solution  contains  some  carbonate  of  magnesia, 
a  part  of  it  in  the  form  of  dolomite  may  be  deposited  in  a  different 
ptut  of  the  rock  from  which  it  was  derived ;  the  waste  of  one  portion 
going  to  help  to  build  up  another.* 

C^e  point  in  favour  of  the  abstraction  theory  is,  that  the  Irish  dolo- 
mites are  exceedingly  porous,  cellular,  or  cavernous.  Another  curious 
point  is  that  the  cavities  are  almost  invariably  filled  with  colcspar ; 
and  not  bitter  spar  or  dolomite,  as  is  generally  stated.  I  have  carefully 
examined  the  dolomitic  limestones  which  occiu:  so  plentifully  in  the 
Counties  Carlow  and  Kilkenny,  and  are  spread  over  a  large  area,  as 
well  as  some  in  the  Counties  Waterford,  and  Tyrone ;  and  I  can  safely 
say  that  in  no  case  have  I.  found  specimens  of  dolomite  or  magnesite 
in  the  cavities,  but,  on  the  contra^,  calcspar  most  abundantly. 

At  Drumreagh,  near  Coal  Island,  Co.  Tyrone,  several  beds  of  dolo- 
mite are  interbedded  with  the  ordinary  blue  fossiliferous  limestone, 
and  one  of  the  beds  merges  gradually  into  the  limestone,  showing  con- 
clusively that  it  is  metcunorphosed  limestone,  and  not  the  result  of 
original  chemical  deposition  on  the  sea  bottom,  according  to  Dr.  Sterry 
Hunt's  theory  of  such  rocks.  It  is  a  light  brown,  extremely  hard, 
crystalline,  but  compact  dolomite;  but  so  very  cavernous  that  it  is  most 
difficult  to  obtain  a  fracture  of  it  showing  the  true  structure.  The 
cavities  are  often  large,  as  much  as  a  foot  in  diameter,  and  coated,  or 
often  entirely  filled,  with  nearly  pure  calcite,  which  may  be  obtained 
in  large,  nearly  transparent  rhombohedrons.  The  dolomite  is  per- 
fectly unaffected  by  acid,  in  the  cold.  I  should  say  that  fully  half 
the  original  rock  is  wanting,  being  now  only  represented  by  the  spar- 
coated  cavities. 


*  I  think  Bitchof  makes  a  similar  suggestion. 


724  Proceedings  of  the  Royal  Irish  Academy. 

It  is  perfectly  clear  that  these  cavities  were  produced  by  the  action 
of  water,  no  doubt  acting  on  the  more  calcareous  parts  of  the  rock, 
which  of  course  would  not  be  homogeneous  in  composition.  Such  a  remo- 
val of  the  lime  in  one  part  might  be  accompanied  nearly  simultaneously 
by  the  deposition  in  a  previously  formed  cavity  of  some  of  the  material 
brought  away.  The  calcareous  water  trickling  down  the  sides  of  such 
a  vacancy  would  have  a  good  opportunity  of  evaporating,  and  deposit- 
ing its  freight.  It  is  possible  in  such  cases  both  the  percolation  and 
the  evaporation  of  the  water  would  be  slower,  and  more  uniform  than 
in  large  caverns ;  and  thus  largely  crystalline  masses  of  calcite  would 
result,  instead  of  finely  crystalline  stciactites. 

This  cellular  character  of  dolomitic  limestone  is  exceedingly  well 
shown  in  a  quarry'  at  Loughry,  near  Cookstown,  County  Tyrone,  in 
which  is  the  following  section : — 

Section  at  Rochheady  near  Loughry. 

Feet.  Inches. 

3.  Boulder  clay, 5  0 

2.  Purplish  crystalline  encrinital  lime- 
stone passing  downwards  into  purple 

dolomitic  limestone,  with  large  cavities,     3  10 

1 .  Sandstones  and  grits, 7  1 

15       11 


The  upper  beds,  which  are  dolomitic,  are  eaten  away  in  curious 
cavities,  as  shown  in  the  sketch  (fig.  1,  Plate  41).  These  were  possibly 
formed  during  the  alteration  of  the  limestone.  They  could  hardly 
have  occurred)  since,  because  dolomite  once  formed  is  so  insoluble. 
The  cavities  also  are  coated  with  calcspar. 

In  the  south-east  of  Ireland  the  carboniferous  limestone  is  much 
dolomitised,  and  affords  good  opportunities  for  the  study  of  that 
mineral.  In  some  places,  as  in  the  county  Garlow,  a  persistent  band 
of  black  dolomite  extends  for  miles,  as  may  be  seen  on  glancing  at  the 
Carlow  Sheet  of  the  Geological  Survey  Map.*  Here  it  occupies  such  a 
definite  position  in  the  carboniferous  series,  that  it  might  be  taken  to 
be  an  important  division  of  it.  The  rock,  where  perfect,  is  hard, 
compact,  and  sub-crystalline,  but  it  is  wonderfully  cellular,  fully  a 
third  of  it  being  wanting.  The  cavities  are,  so  far  as  I  can  judge, 
coated  only  with  calcspar.  After  many  searches  I  was  unable  to  find 
a  single  specimen  of  bitter  spar,  or  dolomite,  which  can  only  occur 
here  in  a  very  few  isolated  localities,  if  at  all. 

Professor  Jukes  made  a  certain  distinction  between  varieties  of  the 


^  Sheet  137. 


Hardmak — On  the  CarJxmiferom  Dolomites  of  Ireland.    725 

dolomites  of  the  south  of  Ireland,  t. «.,  dolomites  of  original  deposition, 
and  dolomites-  produced  hy  alteration  of  the  original  rock,  with  the 
former  of  which  the  Carlow  rock  appears  to  have  been  classed,  while 
that  of  Kilkenny  is  supposed  to  be  metamorphio.  I  rather  think,  how- 
ever, that  they  both  are  mctamorphic,  only  in  different  degrees. 

The  Kilkenny  magnesian  limestones  are  true  dolomites  both  in 
appearance  and  composition.  They  contain  from  30  to  44  per  cent,  of 
carbonate  of  magnesia ;  they  are  usually  very  crystalline,  of  a  light 
yellow  to  a  pearly  grey  colour,  and  do  not  effervesce  when  treated 
with  acid,  except  occasionally  in  the  interstices  between  the  crystals, 
owing  to  infiltrated  carbonate  of  lime.  They  are  remarkable  for  the 
same  cellular  or  cavernous  structure  which  I  have  noticed  in  all  the 
other  dolomites  of  Ireland ;  the  vacancies  being  coated,  or  filled  entirely 
with  calcspar.  In  some  places  the  material  has  been  removed  in  an 
exceedingly  curious  manner,  the  vacant  spaces  running  parallel  to 
each  other,  and  forming  apparently  lines  of  bedding,  which,  however, 
they  are  not,  as  the  true  bedding  is  often  also  visible  in  such  instances. 
Sometimes  they  give  the  similitude  of  false  or  current  bedding,  as  is 
shown  in  the  sketch  (fig.  3,  Plate  41). 

As  a  rule,  the  bedding  %b  obliterated,  and  in  weathering  the  rock 
assumes  at  the  surface  of  the  ground,  or  wheresoever  else  exposed,  a 
ruggedly  pointed  aspect,  as  if  dipping  vertically,  along  the  lines  of 
joints ;  and  this  often  gives  rise  to  picturesque  hillocks  or  escarpments ; 
the  dolomite  remaining,  while  the  more  easily  dissolved  limestone  is 
eaten  away  to  a  lower  and  more  uniform  level,  contrary  to  the  general 
idea  which  assumes  that  dolomite  is  more  soluble  than  limestone,  be- 
cause under  certain  influences  it  disintegrates  more  rapidly.* 

Near  the  city  of  Kilkenny  very  extensive  masses  of  dolomite  occur, 
which  could  only  have  been  formed  by  the  metamorphism  of  the 
original  limestone ;  and  in  one  locality — Riverview,  H  miles  west  of 
the  town — ^there  is  a  very  fair  opportunity  of  studying  the  mode  of  its 
production.     And  it.  will  be  seen  that  this  can  bo  reasonably  explained 


*  A  well-knovn  instance  of  this  is  shown  hy  the  decay  of  the  stones  used  in  the 
present  Houses  of  Parliament,  beingmagnesian  limestones  from  the  Mansfield  Wood- 
house  quairies,  and  from  Anston,  Yorkshire.  (See  Building  and  Ornamental  Stones, 
Prof.  Hull,  p.  200. )  Under  the  influence  of  the  vitiated  atmosphere  of  London,  some  of 
this  stone  soon  commenced  to  crumble  away.  It  must  be  remembered  that  the  disinte- 
gration of  dolomite  is  not  due  always  to  the  dissolution  of  the  whole  rock,  but  is  most 
often  merely  the  result  of  the  solution  of  the  carbonate  of  lime,  which  cements  the 
crystals  of  true  dolomite  together.  Any  one  who  has  obserred  the  process  of  weather- 
ing of  dolomites  will  remember  that  the  minute  crystals  of  which  the  rock  is 
composed  merely  fall  away  from  each  other,  resulting  in  a  loose  sand-like  mass, 
but  they  do  not  readily  decompose. 

According  to  Anstod,  the  most  durable  magnesian  limestones,  for  building  pur- 
poses, are  those  containing  nearly  equal  parts  of  carbonate  of  lime  and  of  magnesia 
in  a  state  of  perfect  combination — ^that  is,  true  dolomite. — See  Ansted's  Geological 
Science  (Orr's  Circle  of  the  Sciences),  p.  208. 


726  Proceedifigi  of  the  Royal  Irish  Academy. 

on  the  theory  put  forwaid  alieadj,  that  is,  the  eztnctionof  caihonate 
of  lime  from  die  limestone  rook. 

A  small  stream  runs  from  the  railway  down  to  the  Nore  at  tins 
place.  On  one  side  of  it,  to  the  south,  dolomite  crops  out,  with  its 
nsnal  ragged  aspect.  On  the  other  side,  blue  fossilif erons  limestone. 
At  first  sight  it  would  seem  that  the  limestone  ended  abruptly  agaiESt 
the  dolomite,  but  in  reality  it  dips  underneath  it.  The  dolomite  pie^ 
sents  the  usual  characteristics,  being  highly  crystalline,  and  full  ot 
drusy  cavities,  with  calcite.  The  limestone  is  a  compact  bluish  nek, 
in  thick  beds ;  the  upper  beds  are  magnesian,  although  not  yet  dolo- 
mitic,  but  they  are  beginning  to  show  the  drusy  cavities,  and  are 
undoubtedly  some  distance  on  their  way  in  the  direction  of  dolooite. 
The  most  interesting  fact,  howeyer,  is,  that  between  every  indiviiiiai 
bed  of  the  limestone  is  a  thick  layer,  or  rather  bed  of  calcite,  from  three 
to  nine  inches  thick ;  and  this  is  even  visible  on  the  top  of  the  uppenaost 
bed,  which  there  is  overlaid  by  a  thin  coating  of  drift  clay  or  soil ;  bet 
eventually  disappears  under  the  dolomite.    (See  fig.  2,  Plate  41.) 

Now  it  is  perfectly  evident  that  the  calcite  layers  are  derived  from 
the  limestone  beds  above  them.  It  would  be  difficult  to  prove  that 
each  layer  was  derived  solely  from  the  immediate  bed  above  it  but 
this  is  not  impossible.  The  excites  are  of  a  fairly  uniform  thickness, 
and  the  quantity  abstracted  from  the  overlying  beds  would  be  quite  sof- 
ficient  to  alter  very  materially  the  composition  of  the  limestone.  These 
beds  are  about  eighteen  inches  thick,  and  the  corresponding  calcites 
three  to  nine  inches.  Taking  the  latter,  and  assuming,  for  argomen: 
sake,  that  the  limestone  originally  contained  about  12  per  cent,  of  C4ir- 
bonate  of  magnesia,  the  removal  of  sufficient  calcite  to  form  a  layer  nino 
inches  thick  would  increase  the  percentage  of  magnesia  carbonate  in  ihe 
limestone  to  over  20  per  cent.,  which  would  nearly  correspond  to  the 
composition  of  some  dolomites. 

One  other  point  with  regard  to  the  Irish  dolomites  I  have  aheady 
partly  referred  to-— viz.,  that  they  help  to  supply  further  evidence  in 
refutation  of  Dr.  Hunt's  theory  as  to  the  origin  of  dolomitic  rocks,  that 
is,  their  original  deposition  as  sediments  from  an  evaporating  sea  basin, 
and  subsequent  modification  by  heat.  I  cannot  do  better  than  here 
quote  more  fully  Dr.  Hunt's  words.  (See  "Conclusions  "  of  Ids  paper 
on  the  Chemistry  of  Dolomites  and  Gypsums.*)  "  Dolomites,  mag- 
nesites,  and  magnesian  marls,  have  had  their  origin  in  sediments  of 
magnesian  carbonate,  formed  by  the  evaporation  of  solutions  of  bicar- 
bonate of  magnesia.  These  solutions  have  been  produced  either 
by  the  action  of  bicarbonate  of  lime  upon  solutions  of  sulphate  of 
magnesia,  in  which  case  gypsum  is  a  subsidiary  product,  or  by  the 
decomposition  of  solutions  of  sulphate  or  chloride  of  magnesium  by  the 
waters  of  rivers  or  springs  containing  bicarbonate  of  soda.  The  tub- 
sequent  action  of  heat  upon  such  magnesian  sediments,  either  alone  of 


•  Chem.  k  Geol.  Esaaya,  p.  90. 


Hardhan — On  the  Carboniferous  Dolomites  of  Ireland.    727 

miingled  with  earhonate  of  lime,  has  changed  them  into  magnesite  or  dole- 
tnitey  I  cannot  see  that  this  theory  d&ers  in  any  essential  respect 
from  that  of  Von  Morlot  (see  ante,  p.  705),  which  Hunt  himself  con- 
demns ;  hut  it  altogether  fails  to  account  for  what  frequently  occurs 
near  Kilkenny. 

(1).  The  dolomites  are  often  interstratified  with  ordinary  blue 
limestone  highly  fossilif erous.  The  section  at  Eiverview  is  one  out  of 
many  that  shows  this.  On  the  evaporation  theory  we  should  suppose 
a  most  extraordinary  series  of  oscillatory  movements,  alternating  be- 
tween a  deep  and  clear  sea,  fitted  to  sustain  the  life  of  corals  and  such 
organisms,  and  again  a  land-locked  lagoon  merging  into  a  salt  lake : 
all  this  repeated  many  times,  in  the  process  of  producing  a  few  hundred 
feet  of  the  interstratified  rocks.  This  is,  I  venture  to  say,  inconceiv- 
able. In  order  to  get  a  deposit  of  carbonate  of  lime  alone,  at  least  three- 
fourths  of  the  sea  water  must  be  evaporated,  as  Bischof  has  shown  ;*  but 
even  then  the  carbonate  of  magnesia  will  remain  in  solution  a  considera- 
ble time  longer.  By  the  time  the  water  became  sufficiently  dissipated 
for  the  latter  to  subside,  the  sea  would  have  become  a  veritable  pickle 
in.  which  few  organic  forms  could  live.f  Yet  we  have  highly  fossili- 
f  erous  dolomites,  which  would  prove  that  the  animals  lived  in  the  sea 
-water  during  the  time  of  the  depodtion  of  those  rocks,  and  that,  during 
a  Tery  considerable  time  besides. ''  In  fact,  on  the  evaporation  theory 
we  should  have  only  the  following  distinct  groups : — (1),  carbonate 
of  lime;  (2),  magnesite;  (3),  gypsum;  (4),  common  salt;  but  no 
dolomite.  It  is  quite  possible,  however,  that  some  dolomites,  such  as 
those  of  the  Permian  formation,  may  have  been  indirectly  the  result 
of  evaporation  ;  thus,  that  during  the  process  of  concentration  a 
greater  amount  of  carbonate  of  magnesia  might  be  assimilated  by  the 
animals  then  living  in  the  lagoon ;  and  thus  that  the  alteration  to  dolo- 
mite might  be  sooner  effected  afterwards.  It  seems  to  me  that  it  is 
only  by  this  assimilation,  dnd  the  subsequent  removal  of  the  excess  of 
carbonate  of  lime,  that  large  masses  of  dolomite  could  be  formed ;  for 
if  we  consider  the  very  small  percentage  of  carbonate  of  magnesia  or 
Hme  present  in  sea  water,  and  suppose  even  a  portion  of  it  enclosed  in 
a  position  favourable  to  evaporation,  it  is  clear  that  the  beds  of  sulphate 
of  lime,  and  of  the  chlorides,  would  bear  an  enormous  proportion  to  those 
of  carbonate  of  magnesia  or  lime,  or  to  dolomites. 

(2).  Again ;  were  the  dolomites  originally  deposited  chemically, 
they  should  form  perfectly  definite  beds----dolomite,  and  nothing  else. 
It  would  be  perfectly  impossible,  under  any  circumstances  of  evapo- 
ration, to  have  the  same  bed  at  one  place  Hmestone  highly  fossilif e- 
rous,  and  at  another  (a  few  yards  off)  truly  dolomitic,  the  fossils 


•  Chwn.  Geol.,  i.,  p.  177. 

t  Except  perhaps  those  remarkable  salmon  which,  as  related  hy  Smollett,  in 
«  Humphrey  Clinker,"  the  Scottish  laird  kept  in  a  tank,  to  which  he  ^tidually  added 
more  and  more  salt,  &c. ;  so  that  at  last  thty  could  be  taken  alive  ready  pickled  I 


728 


Proeeedingi  of  the  Bot/al  Irish  Academy. 


altogether  obliterated.  But  this  Ib  a  constant  occurrence  among  Irish 
dolomites.*  I  have  already  referred  to  one  instance  of  it  in  the  Co.  Ty- 
rone ;  it  is  also  frequent  in  the  County  Kilkenny,  in  many  places  within 
a  circle  extending  from  Oowran  to  near  Ballyragget ;  and  I  have  hand 
specimens  showing  the  gradual  alteration,  the  fossils  being  completely 
obliterated,  and  the  blue  limestone  at  one  side  becoming  perfect  crys- 
talline dolomite  at  the  other.  Large  masses  of  dolomite  are  seen, 
which,  when  traced  out,  are  found  to  abut  against  and  merge  into 
limestone,  and  in  some  places,  as  at  Ballyf oyle,  there  will  be  as  many 
as  twenty  or  more  alternations  of  limestone  and  dolomite  in  a  distance 
of  less  than  half  a  mile ;  the  limestone  always  full  of  marine  fosailsy 
by  no  means  dwarfed  in  appearance.     (See  figs.  4,  5,  6,  Plate  42). 

[^NoU  added  in  Preu, — I  have  mentioned  Uiat  limestones  are  by  no 
means  homogeneous  in  composition,  and  that  the  cellular  structure  would 
be  capriciously  determined  by  the  most  calcareous,  and  therefore  most 
soluble  parts.  I  have  lately  analysed  some  limestones  from  Ballyf  oyle, 
which  are  interlarded  with  and  pass  into  dolomite.  The  following  were 
made  from  specimens  of  the  same  bed,  taken  a  few  yards  apart : — 

ANALTSIS  OF  LIUKSTOKE  FB03I  BALLTFOTLB. 


I. 

11. 

Carbonate  of  lime,      .     . 

„       „  magnesia,  . 

Ferric  oxide  and  alumina, 

Insoluble  residue,  .    .    . 

87-72 
3-80 
2-62 
6-80 

91  06 
1-00 
2-05 
6-70 

99-84 

99-81 

Specific  Gratitt,  2*89. 

Specific  Chravity  of  Dolomite. — On  the  principle  I  have  advocated^ 
viz.,  the  removal  of  carbonate  of  lime  from  limestones,  and  the  conse- 
quent porosity  of  the  resulting  dolomite,  the  specific  gravity  ought  to 
be  less  than  that  of  limestones.  I  am  aware  that  Dr.  Apjohn  has,  in 
the  paper  already  cited,  stated  the  contrary ;  but  it  must  be  remem- 
bered that  the  determination  is  rendered  very  difficult  in  the  case  of 
dolomite  by  the  circumstance  that,  while  in  the  mass,  it  is  porous  and 
cellular,  and  must  be  of  less  specific  gravity  than  limestones,  which  are 
compact — the  small  pieces,  which  could  only  be  weighed  on  our 
balances,  are  usually  compact.  However,  those  I  have  tried  certainly 
possess  a  lower  specific  gravity  than  limestone.  This  is  shown  in  the 
examples  given  above  of  the  Ballyfoyle  dolomite  and  limestone.] 


*  Bischof  refers  also  to  tlua  fact  as  common  to  dolomitio  formations. 


Hardman — On  the  Carboniferous  Dolomites  of  Ireland.    729 

Crystallnatum.^^The  veiy  distinct  crystalline  appearance  of  dolo- 
mite is  a  matter  requiring  important  consideration,  but  it  is  in  truth 
one  of  the  chief  difficulties  of  the  whole  question.  From  whatever 
stand-point  we  approach  the  subject,  and  whatever  the  theory  which 
we  adopt  may  be,  this  is  not  very  easy  to  account  for.  The  infiltra- 
tion of  carbonate  of  magnesia  could  hardly  of  itself  afford  this  peculiar 
structure,  for  it  would  only  give  a  perimorph,  or  at  least  a]  pscudo- 
morph,  of  magnesite,  ^y  replacing  part  of  the  carbonate  of  lime  in  the 
calcite.  But  even  magnesite  after  calcite  is  not  frequent.  Blum  and 
others  refer  to  it  as  occasionally  occurring inlodes,  and  in  geodic  cavities ; 
but  it  is  not  likely  often  to  be. discovered,  for  Bischof  found  it  impos- 
sible to  effect  any  decomposition  between  carbonate  of  lime,  and  a 
solution  of  bicarbonate  of  magnesia.* 

On  the  other  hand,  all  limestones,  with  the  exception  of  the  earthy 
varieties,  are  more  or  less  crystalline,  and  the  crystals  of  calcite  differ 
only  to  a  very  slight  amount  from  those  of  dolomite — so  little  that  the 
principal  angle  of  the  rhombohedron  of  calcite  being  105^5',  that  of 
dolomite  is  106^15',  a  difference  quite  inappreciable,  without  the  aid 
of  delicate  instruments.  This  being  so,  if  a  quantity  of  superabun- 
dant carbonate  of  lime  be  removed  from  a  highly  magncsian  limestone, 
such  as  would,  according  to  Bischof,  be  formed  by  the  agency  of  certain 
organisms,  the  crystalline  structure  would  appear  very  distinctly, 
oven  in  magnesian  limestones  that  were  still  far  removed  from  dolo- 
mites. In  fact  in  few  dolomites  are  the  crystals  really  distinct  until 
the  rock  has  begun  to  decompose,  and  I  could  point  out  many  loca- 
lities near  Kilkenny  where  true  dolomites  are  peifectly  compact,  to  all 
appearance,  where  unweathered,  but  once  attacked  by  the  atmosphere 
show  themselves  to  be  highly  crystalline ;  the  process  being  just 
what  I  have  suggested  above,  viz.,  the  removal  of  the  supei^uous 
carbonate  of  lime.  This  is,  however,  an  extremely  difficult  province 
of  the  question  to  enter  upon,  and  an  opinion  on  it  is  not  to  be 
advanced  without  great  diffidence,  during  the  existing  state  of  our 
information  about  it. 

Conclusions, — (1).  It  appears,  therefore,  that  the  Irish  carbonife- 
rous dolomites  could  not  have  been  completely  originated  by  organic 
agency,  nor  could  they  have  been  formed  by  chemical  deposition 
due  to  evaporation  of  sea  water ;  and  there  seems  to  be  evidence  of 
few  other  dolomites  being  formed  in  the  latter  way. 

(2).  The  experiments  recorded  in  the  preceding  paper,  showing  the 
much  greater  solubility  of  carbonate  of  lime  than  of  carbonate  of  mag- 
nesia, from  rocks  treated  with  a  carbonic  acid  solution,  appear  to  bear 
out  the  theory  that  dolomite  may  be  formed  by  the  extraction — by 
water  holding  in  solution  small  quantities  of  carbonic  acid-— of  the 
excess  of  carbonate  of  lime  from  magnesian  limestone  rocks. 

In  this  way,  also,  it  is  easy  to  account  for  the  fissures  and  cavities 


'  See  Kote  to  p.  708. 


730  Proceedings  of  the  Boffol  Iruh  Aeademy. 

8o  common  to  dolomites,  and  the  filling  np  or  coating  of  these  cairities 
with  carbonate  of  lime. 

The  frequent  occurrence  of  qnantities  of  carbonate  of  sine  in  dolo- 
mites may  also  be  explained  thns  :  the  concentration,  simnltaneonBlj, 
of  the  carbonates  of  zinc  and  of  magnesia  being  accomplished  bj  the 
remoTal  of  the  carbonate  of  Hme.*  The  resolting  dolomite  being 
then  less  soluble  that  the  carbonate  of  zinc,  the  latter  wonld  be  dis- 
solved out  and  again  deposited  alone  in  the  lower  cavitiea  of  the 
rock. 

On  the  other  hand,  the  percolation  of  water  containing  carbonate 
of  magnesia  would  add  to  the  bulk  of  the  mass,  unless  something  was 
abstracted  in  place  of  the  carbonate  of  magnesia  deposited.  This 
could  only  be  carbonate  of  lime,  but  Bischof  s  experiment  is  against 
that.  B^des,  as  water  usually  contains  about  ten  times  as  much 
carbonate  of  lime  as  of  magnesia,  were  any  deposition  to  take  place, 
the  lime  would  certainly  be  deposited  before  the  magnesia,  and  would 
not  only  increase  the  bulk,  but  neutralise  the  dolomitization. 


*  I  hftTe  ab-eadj  pointed  out  tliat  zinc  is  nearly  always  aiaodated  with,  or  an 
accessoiy  of,  maffnesian  minerals.  Vide  On  the  supposed  Substitution  of  Zzbc  for 
Magnesium  in  Minerals,  Proc.  Koy.  Ir.  Acad.,  1874. 


Bbynolds — Beport  on  Qlucinum.  731 


LYI. — Kefoets  7B0H  THS  Chemicax  Labobatoet  of  TsnriTT  College, 
Dublin.  By  J.  Emebson  Eetnolds,  M.  J),,  M.  R.  I.  A.,  Professor 
of  Chexnistay,  University  of  Dublin. 

No.  1. — Ojt  GLXJcnnTM :  its  Atomic  Weight  ajscl  Specific  Heat. 

[Bead  April  10, 1876.] 

Amongst  the  few  rare  elements  found  in  Ireland  is  the  metal  Gluci- 
num  or  Beryllium,  which  occurs  in  the  well-known  alumino-glucinio 
silicate,  beryl  or  "  emerald ; "  this  mineral  is  found  in  comparative 
abundance,  though  in  a  rough  state,  in  the  granites  of  Donegal, 
and  is  somewhat  less  freely  distributed  through  the  granites  of  tlie 
Moume  Mountains  in  the  county  of  Down.  As  the  "  atomic  weight " 
of  glucinum  has  not  yet  been  definitely  fixed  by  the  determination  of 
the  specific  heat  of  the  metal,  it  seemed  desirable  that  we  in  Ire- 
land should  make  the  necessary  crucial  experiments.  Hence,  about 
seven  years  ago,  I  commenced  to  collect  the  crude  Irish  beryls  or 
''emeralds,"  and  ultimately  succeeded  in  obtaining  3  kilogrammes 
of  the  dressed  mineral,  from  which  I  prepared  nearly  350  grammes  of 
the  pure  glucinic  oxide. 

I  have  to  thank  my  friend  Mr.  William  Harte,  C.  E.,  the  ex- 
cellent County  Surveyor  of  Donegal,  for  the  valuable  assistance  he 
kindly  afforded  me  in  collecting  much  of  the  mineral  from  which 
the  glucinic  oxide  was  prepared. 

The  satisfactory  nature  of  the  results  of  a  set  of  preliminary  experi- 
ments with  the  material  at  my  disposal  must  be  my  apology  for 
la3ring  a  short  communication  upon  the  subject  before  the  Academy, 
at  a  very  early  stage  of  the  investigation. 

Some  glucinic  oxide  was  converted  into  the  anhydrous  chloride  by 
the  action  of  chlorine  upon  it  at  a  full  red  heat  in  presence  of  finely 
divided  carbon;  and  the  metal  was  subsequently  procured  by  the  action 
of  metallic  sodium  on  the  pure  sublimed  glucinic  chloride.  The  reduc- 
tion was  effected  by  heating  a  suitable  mixture  in  a  platinum  vessel, 
but  the  temperature  was  not  allowed  to  rise  sufficiently  to  liquefy  tho 
mass ;  and  on  removal  of  the  material  from  the  crucible  those  portions 
which  had  been  in  contact  with  the  platinum  were  rejected.  The 
resulting  mixture  of  sodic  chloride  and  reduced  glucinum  was  then 
fused  under  common  salt  in  a  lime  crucible ;  this  precaution  was 
taken  in  order  to  avoid  contact  with  siliceous  compounds.  Con- 
siderable loss  occurred  in  this  operation ;  but  I  succeeded  in  obtaining 
a  small  coherent  mass  of  metallic  glucinum,  which  latter  was  found 
to  agree  in  characters  with  the  metal  described  by  Debray,*  though 


•  AnnaUi  dt  Chimie  et  d$  Fhysique :  troisi^inc  sine,  torn.  xLv.,  p.  o  (1855). 


732  Proceeding$  of  the  Royal  Irish  Acudemy. 

that  diBtingmshed  chemist  effected  the  reduction  of  his  metal  in  a 
different  manner. 

If  we  admit  with  Awdejew,  and  with  Debray,  the  number  4*6  to 
be  the  equivalent  of  glucinum  (H  "=  1),  the  question  remains  whether 
the  '*  atomic  weight,"  so  called,  is  a  multiple  of  the  equivalent  by 
2  or  3. 

If,  as  some  assert,  the  ''  atomic  weight "  is  4'6  x  3  =  13*8,  the  only 
known  oxide  of  glucinum  must  resemble  alumina.  If,  on  the  other 
hand,  the  atomic  weight  is  4*6  x  2  =  9*2,  glucinamustbe  an  oxide  like 
that  of  zinc  or  of  magnesium.  Each  view  has  received  the  support  of  a 
group  of  chemists  of  t^e  highest  eminence,  but  owing  to  peculiar  difficul- 
ties surrounding  the  case,  an  appeal  to  chemical  criteria  has  hitherto 
been  insufficient  to  decide  between  the  two  conflicting  opinions — ^a  deter- 
mination of  the  specific  heat  of  the  metal,  or  of  the  vapour  density  of  one 
of  its  compounds  of  simple  constitution,  being  necessary  for  tibe  final 
settlement  of  the  question.  Of  these  methods  I  chose  the  former,  and, 
having  made  several  determinations  of  the  capacity  for  heat  of  metallic 
glucinum,  I  have  the  gratification  to  state  that  the  data  obtained 
lead  to  the  conclusion  that  the  atomic  weight  of  glucinum  is  double 
the  equivalent  weight.  Glucinum  is,  therefore,  a  diatomic  metal  with 
an  atomic  weight  of  9*2 ;  though,  I  may  add,  this  number  may  be 
slightly  affected  by  a  new  determination  of  the  equivalent  in  which 
I  am  engaged. 

The  method  pursued  in  making  the  necessary  determinations  upon 
which  to  found  the  conclusion  just  stated  was  devised  for  the  pur- 
pose of  this  inquiry ;  and  as  it  is  essentially  different  from  any  with 
which  I  am  acquainted,  I  may  be  permitted  to  indicate  very  briefly 
the  plan  adopted  after  a  good  deal  of  preliminary  investigation.* 

The  well-known  law  of  Dulong  and  Petit,  as  modified  by  Can- 
nizzaro,  asserts  that  the  atoms  of  elementary  matter  have  the  same 
capacity  for  heat,  when  we  compare  them  in  the  solid  state.  The 
outstanding  exceptions  to  this  important  law  are  few,  and  even  these 
appear  to  have  been  cleared  away  in  some  degree  by  the  recent  re- 
searches of  Weber  on  the  specific  heats  of  silicon,  boron,  and  carbon. 
The  principle,  however,  is  admittedly  sufficiently  general  in  its  appli- 


•  The  preparatioii  of  pure  metallic  riucinum  in  quantities  exceeding  two  or 
three  grammes  is  difficult  and  costly ;  for  this  amongst  other  reasons,  1  determined 
to  employ  Bunsen's  admirable  and  theoreticallj  perfect  ice  calorimeter  in  tiie  esti- 
mation dt  the  specific  heat  of  the  metal,  as  small  quantities  of  material  only  are 
required.  It  proved,  however,  to  be  impossible,  owing  to  various  engagements,  to 
prepare  the  glucinum  in  a  state  of  sufficient  purity  until  the  season  had  paoed 
when  Bunsen's  ice  calorimeter  can  be  conveniently  used.  I  had,  therefore,  to 
devise  a  calorimetric  method  which  could  be  employed  during  warm  weather,  and 
which  could  afford  trustworthy  results  with  smaU  weights  of  material.  I  have 
given  in  the  text  an  outline  of  this  method,  but  the  details  of  its  application  to  the 
determination  of  atomic  and  molecular  heat  will  form  the  subject  of  an<^er  com- 
munication. 


Beynolds — Report  on  Olucinum.  733 

cation  to  enable  us  to  found  upon  it  a  plan  for  the  determination  of 
the  atomic  weight  so  called  of  a  particular  element :  for  it  is  evident 
that  if  we  employ  as  a  standard  a  metal  whose  atomic  weight  and 
specific  heat  are  both  accurately  known — silver  for  example  (=  108)— 
the  weight  of  another  solid  element  which  contains  the  same  quantity 
of  heat  at  100°  C.  as  108  parts  of  pure  silver  at  100°  C.  is  the  atomic 
weight  of  the  element.  In  seeking  to  compare  glucinum  with  pure  me- 
tallic silver  in  this  way,  I  succeeded  in  arranging  an  experimental 
method  which  not  only  enabled  me  to  attain  the  object  I  had  in  view, 
butalso  to  demonstrate  the  truth  of  the  law  just  referred  to.  The  appa- 
ratus required  is  easily  constructed,  and  consists  of  a  spirit  thermometer 
with  a  cylindrical  "bulb"  in  which  a  test  tube  is  sealed  after  the  manner 
of  Bunsen's  ice  calorimeter.  This  part  of  the  apparatus  is  easily  con- 
structed from  a  small  chloride  of  calcium  drying  tower  as  shown  in  the 
diagram.  Although  the  larger  **  bulb ''  of  the  thermometer  is  filled  with 


spirit,  the  lower  one  and  the  stem  are  full  of  mercury,  and  connected 
with  a  fine  capillary  tube  carefully  graduated  in  millimetres^  and  cali- 
brated. The  arrangement  constitutes  an  exceedingly  delicate  spirit 
thermometer,  with  a  mercury  index. 

When  it  is  desired  to  compare  a  solid  element  with  silver,  in  order 
to  fix  the  atomic  weight,  it  is  necessary  to  make  a  preliminary  experi- 
ment with  the  stands^  metal.  For  this  purpose  one  cubic  centimetre 
of  distilled  water  is  placed  in  the  test  tube  which  is  immersed  in  the 
bulb  of  the  thermometer,  and  when  the  temperature  has  been  equal- 
ised, and  the  thread  of  mercury  has  reached  a  suitable  position  in  the 


734  Proeeedingn  of  the  Royal  Irish  Academy. 

stem,  a  piece  of  pore  nlver  weighing  108  centigrammes,  and  heated 
to  100^  C.  in  steam,  is  rapidlj  dropped  into  the  cubic  centimetre  of 
water,  and  the  expansion  caused  in  a  given  time  carefully  noted.* 
According  to  the  law  above  stated,  a  centigramme  atom,  if  I  may  use 
the  term,  of  any  other  metal  than  silver  ought  to  cause  exactly  the 
same  expansion,  when  the  experiment  is  made  with  it  under  precisely 
the  same  conditions ;  and  these  conditions  are  very  easily  realised. 
I  have  ascertained  that  such  is  the  case,  and  the  approximate  equality 
in  " atomic  heat"  of  many  of  the  metals  has  thus  been  easily  demon- 
strated. 

The  comparison  of  glucinum  with  silver  was  made  on  this  plan, 
and  it  was  found  that  the  weight  of  glucinum  which  contains  nearly  the 
same  quantity  of  heat  at  100^  C.  as  108  centigrammes  of  silver  at  the 
same  temperature,  is  not  4*6  or  4*6  x  8,  but  4*6  x  2,  or  9-2  centi> 
grammes. 

The  ''  atomic  heat"  of  silver,  or  the  product  of  the  specific  heat 
(s  -05701  according  to  Begnault),  into  the  atomic  weight  (=  108) 
is  6*157.  Using  this  number  as  the  standard  for  reference,  the 
experimental  number  found  for  the  atomic  heat  of  the  specimen  of 
glucinum  operated  with  is  5-91.    Thus : — 

Atomic  heat  of  silver         «  6*157 
Atomic  heat  of  glucinum  ^  5*910 

The  difference  is  less  than  the  known  difference  between  the 
atomic  heat  of  silver  and  that  of  aluminium ;  but  I  am  inclined  to 
think  that  the  lower  number  found  for  the  glucinum  used  is  due  to 
the  presence  of  a  trace  of  platinum  in  the  specimen  of  metal.  Owing 
to  the  high  atomic  weight  of  platinum  («  197*1),  as  compared  with 
that  of  glucinum  (9*2),  the  presence  of  even  a  small  quantity  of  the 
former  metal  must  very  sensibly  affect  the  determination  of  the 
atomic  heat  of  glucinum.  I  hope  soon  to  be  in  a  position  to  continue 
these  experiments  with  the  |?iiw  metal. 

It  will,  however,  appear  from  the  following  considerations  that 
we  may  fairly  regard  the  above  determination  of  the  atomic  heat  of 
glucinum  as  being  of  such  value  as  to  enable  us,  even  at  an  early 
stage  of  the  inquiry,  to  use  it  as  a  physical  control,  and  to  fix  the 
atomic  weight  of  the  metal,  subject  of  course  to  the  probably  small 
change  in  tiie  numerical  expression  which  may  prove  to  be  necessary 
as  the  investigation  proceeds. 

If  we  assume  the  atomic  weight  of  glucinum  to  be  9-2  and  employ 
the  value  I  have  obtained  for  the  atomic  heat,  t.  e.,  5-91,  we  con  cal- 
culate the  specific  heat  of  the  metal  by  means  of  the  formula. 


*  The  apparatus  is  carefully  protected  from  the  influence  of  air  currents  dmiog 
the  experiment. 


Betnolds — Eeport  on  Olucinum,  735 

»-r m 

^hcn  S  represents  the  specific  heat,  H  the  atomic  heat,  and  A  the 
atomic  weight  of  an  element.  The  specific  heat  of  glucinum  thus 
calculated  is  '642. 

If  now  we  suhstitute  for  H  a  constant,  which  in  this  case  is  the 
product  of  the  well-ascertained  atomic  weight  of  silver*  into  its  equally 
well  determined  specific  heat,  A  S  =  6*157,  the  expression  becomes 

8.^..  ....  m 


and  with  its  aid  we  cau  calculate  the  specific  heat  of  any  solid  element, 
if  its  atomic  weight  is  known  or  assumed.  I  have  thus  calculated  the 
specific  heat  of  glucinum  on  the  assumption  (a)  that  its  atomic  weight 
is  9*2 ;  (h)  that  its  atomic  weight  is  4*6,  and  (e?)  that  it  is  13-8. 

The  results  are  compared  in  the  following  Table  with  the  specific 
heat  obtained  by  calcidation  from  the  actual  determination  of  the 
atomic  heat  of  the  metal : — 

Specific  heat  of  glucinum  calculated  (1)  from  the  result  of  deter- 
mination of  atomic  heat, 

When  A  =  9-2,       -642. 

Specific  heat  of  glucinum  calculated  by  (2), 

When  A  =  92,  ....  -669 
When  A  =  4*6,  ....  1-338 
When  A  =  138 -446 

I  am,  therefore,  justified  in  concluding  that  the  atomic  weight  of 
glucinum  is  nearly  if  not  exactly  9*2. 


*  We  might  obyionsly  take  any  other  product,  but  that  of  ailver  is  here  pre- 
feired  because  the  atomic  heat  of  that  metal  has  been  employed  as  the  standard  for 
Tcfcrence. 


R.  I.  A.  FROC,  SBR.  TI.,  TOL.  n.,  tCIBNGS.  3  X 


r36 


Proceedings  of  the  Boyal  Irish  Academy. 


LYII. — ^Oir  THX  Chevical  Chaitois  which  tazb  plack  nr  thx  Potato 

DUXme   THB    FB0OKE88   OF    THB   DuKAjBX.       Bj   the  RST.    JoHH    H. 

JxixxTT,  B.D.,  S.F.T.C.D. 

[Retd  May  22,  1876.] 

Thv  object  of  the  experiments  described  in  this  paper  was  two-fold, 
namely : — 

1.  To  ascertain  whether  there  b^  any  development  of  sngar  in  the 
tuber,  and  if  so,  what  is  the  kind  of  sugar  developed. 

2.  To  ascertain  whether  there  be  any  perceptible  change  in  the 
quantity  of  nitrogen. 

The  experiments  were  conducted  as  follows.  Four  specimens  wen 
taken  from  the  same  variety  of  potato,  vix. : — 

1.  Perfectly  sound  potato. 

2.  Apparently  sound  part  of  potato  in  which  the  disease  had  ju^ 
begun  to  appear. 

3.  Apparently  sound  part  of  potato  in  which  the  disease  was  far 
advanced. 

4.  Discoloured  part  of  diseased  potato. 

These  specimens,  having  been  carefully  weighed,  were  severally 
grated,  then  subjected  to  a  strong  pressure  in  a  screw  press,  and 
finally  exhausted  with  spirit. 

I'he  fluid  so  obtuiucd  was  filtered,  to  remove  the  albumen  and 
starch,  and  (the  spirit  having  been  distilled  off)  was  diluted  with 
water  to  a  known  bulk.  It  was  then  examined  in  the  usual  way  for 
sugar.     The  result  is  given  in  the  following  Table. 

Tabu  I. 


I. 

II. 

77-24 
•36 
•29 
•65 

III. 

IV. 

Water  (percentage  in  tuber), 
Nitrogen             (do.J 
Sucrose              (do.) 
Glucose              (do) 

73-09 
•27 
•08 
•42 

8004 

•31 

I-I4 

•76 

79-28 
•26  ! 
•21 

For  the  second  part  of  the  experiment  four  specimens^  selected  n 
before,  were  careful! j  weighed  and  dried.  They  were  then  burned  in 
the  usual  way,  for  the  purpose  of  estimating  the  quantity  of  nitrogoi. 
The  results  arc  given  in  the  following  Table. 


Jbllett — On  the  Chemical  Changes  in  Potato  Disease.    737 


Table  II. 


I. 

II. 

III. 

IV. 

Nitrogen  (percentage  in  dry  residue), 
Sucroae                      (do.) 
Glucose                     (do.) 

100 

•29 

1*59 

1-63 
1-27 
2-86 

1-55 
5-71 
3-81 

1-26 
100 
1-93 

The  history  of  these  chemical  changes  seems  to  be  as  f oUows : 

The  first  stage  of  the  disease  in  the  tuber  is  marked  by  an  increase 
in  the  quantity  of  nitrogen. 

This  increase  seems  to  have  attained  its  greatest  value  before  the 
tippearance  of  any  discoloration  in  the  tuber. 

The  same  stage  of  the  disease  is  dso  marked  by  the  development 
of  sugar,  both  glucose  and  sucrose. 

In  the  second  stage,  marked  by  a  great  increase  in  the  discoloured 
part  of  the  tuber,  the  part  which  remains  apparently  sound  shows  no 
increase  of  nitrogen  but  a  very  considerable  increase  in  the  quantity 
of  sugar. 

Finally,  in  the  discoloured  part  of  the  tuber,  there  is  a  diminution 
both  in  the  percentage  of  nitrogen  and  in  the  percentage  of  sugar. 

Now  it  must  be  remembered,  that  in  the  vegetable  kingdom  the 
fungi  contain  the  largest  percentage  of  nitrogen,  approaching  nearly 
in  this  respect  to  the  animal  kingdom.  A  marked  increase  in  the 
<iuantity  of  nitrogen  would  therefore  seem  to  indicate  a  fungoid  growth 
in  the  tuber.  It  would  seem  also  that  this  growth  attains  a  maximum 
value  before  the  tuber  shows  any  visible  sign  of  disease. 

The  development  of  sugar  appears  to  come  somewhat  later;  at 
least  it  continues  for  a  considerable  time  after  the  pereentage  of  nitro- 
gen has  attained  its  maximum  value.  There  can  be,  I  suppose,  no 
"doubt  that  this  sugar  is  formed  by  the  conversion  of  the  stareh,  which 
the  potato  contains  in  large  quantity.  If  the  sugar  produced  were 
wholly  glucose,  there  would  be  no  difficulty,  as  the  presence  of  a 
small  quantity  of  acid  would  be  sufficient  to  account  for  the  pheno- 
menon. But  I  am  not  aware  that  there  is  any  known  method  by 
which  starch  can  be  made  to  pass  into  sucrose.  It  is  possible  that 
this  effect  may  be  produced  by  the  presence  of  the  fungus,  which  is 
indicated  by  the  increased  quantity  of  nitrogen.  I  have  not,  however, 
succeeded  in  establishing  experimentally  tiie  possibility  of  this  con* 
version. 

The  appearance  of  discoloration  marks  the  commencement  of  decom* 
position,  and  is  attended,  as  we  might  naturally  expect,  by  a  diminutioiL 
in  the  quantity  both  of  nitrogen  and  of  sugar. 

8X2 


738  Proceedings  of  the  Royal  Irish  Academy, 


LVIII. — Kemabks  on  the  Recent  Discovert  of  Kemaiks  of  xmc 
Cebtus  Meoacebos  at  Balltbetaoh.    Bj  George  Porte,  M.  R.  I.  A» 

[Read  June  12, 1876.] 

Mant  years  ago  I  took  great  interest  in  the  discovery:  of  the  remains- 
of  the  Cervus  Megaceros  in  various  parts  of  Ireland,  but  during  tha 
recent  explorations  at  Ballybetagh  I  had  an  opportunity  of  examining- 
them  in  situ,  under  conditions  differing  so  much  from  all  that  had 
previously  come  under  my  notice,  that  I  think  it  desirable  to  place  on 
record  these  unusual  circumstances. 

I  am  indebted  to  the  courtesy  of  Mr.  Moss  for  the  opportanity  oT 
making  my  observations  without  any  of  the  labour  and  trouble  of 
superintending  the  excavations. 

I  have  made  the  following  notes  as  a  supplement  to  his  Report,*" 
which  could  not  be  more  accurate  than  it  is,  but  it  treats  only  of  the 
mode  of  conducting  the  exploration,  and  the  results  obtained.  I  may 
observe  that  he  is  not  in  any  way  responsible  for  the  opinions  herein 
expressed ;  indeed,  I  have  reason  to  think  that  he  has  not  arrived  at 
the  same  conclusions  as  I  have  on  all  points. 

Judging  from  the  dip  of  the  sides  of  the  valley  where  these  remains 
were  found,  and  comparing  it  with  the  excavations  made,  it  appears 
that  the  central  parts  were  originally  some  15  feet  below  the  present 
surface,  and  that  a  considerable  stream  or  torrent  ran  through  it.  It 
also  appears  that  at  a  very  remote  period  i;his  torreot  was  obstructed 
by  some  means  or  other,  converting  that  part  of  the  valley  into  a 
shallow  lake  or  tarn,  from  an  acre  to  an  acre  and  a-half  in  area,  and 
in  no  part  more  than  about  15  feet  deep ;  this  tarn  is  now  completely 
filled  up  with  the  u^ual  lacustrine  deposits  (marl  excepted),  of  which 
none  appeared  in  the  excavations  made,  although  a  considerable  deposit 
of  marl  is  found  in  a  similar  but  larger  basin,  a  couple  of  hundred 
yards  lower  down  the  valley. 

Beneath  the  lacustrine  deposits,  lying  on  the  bottom  of  the  tarn, 
that  is  to  say,  on  the  original  surface  of  the  valley,  the  remains  wer& 
found  in  immense  quantities,  firmly  imbedded  between  the  water- 
worn  boulders  which  were  thickly  scattered  over  it. 

In  almost  every  county  in  Ireland  similar  remains  have  from  time^ 
to  time  been  found,  and  still  a  very  common  error  prevails,  even  among 
well-informed  people,  that  they  are  always  found  in  hoys :  this  error 
originates  in  the  custom  of  giving  the  general  name  of  **  bog"  to  every 
place  where  turf  may  be  cut  for  fuel,  whether  it  be  a  true  peat-moss^ 
or  the  basin  of  an  extinct  lake. 

Now  I  have  never  been  able  to  trace  a  single  instance  in  which 
remains  of  the  Cervus  Megaceros  were  found  in  a  real  bog.    So  far  as 


*  Antea,  p.  547. 


Porte — (hi  Remaim  of  Cervus  Megaeeros.  739 

I  am  aware,  they  have  hitherto,  with  one  exception,*  been  found  only 
in  extinct  lakes  ;  and  even  in  these  they  never  occur  in  the  vegetable 
mould  forming  the  upper  stratum  or  bog,  but  always  in  sedimentary 
marl,  or  blue  clay,  which  underlies  the  bog;  and  when  both  these 
deposits  exist  in  the  same  basin,  the  remains  are  generally  found 
imbedded  tn  the  marl,  and  resting  an  the  blue  clay :  the  present  being 
(so  far  as  I  am  aware)  the  first  instance  of  their  being  found  resting 
•on  the  bottom  of  the  basin. 

In  the  marl  or  in  the  blue  clay  they  have  been  found  at  different 
'depths  in  different  basins,  and  sometimes  even  in  the  same  basin,  in- 
dicating that  they  were  deposited  at  different  periods  during  the 
iormation  of  the  stratum :  and  hence  naturalists  have  been  led  to  attri- 
bute the  death  of  the  animals  to  '' miring''  during  their  struggles  with 
their  prcdaceous  enemies. 

This  hypothesis  is  probably  in  some  instances  correct,  but  it  is 
-difficult  to  reconcile  it  with  the  often  observed  fact  of  the  wide  dis- 
persion of  the  bones,  and  still  more  with  another  well-known  fact, 
namely — that  heads  and  antlers  are  frequently  found  where  no  other 
parts  of  the  skeleton  can  be  discovered. 

There  is  at  first  sight  an  apparent  coincidence  between  the  situation 
of  these  remains  and  that  of  most  others  previously  discovered,  but 
the  coincidence  is  only  apparent,  while  it  is  a  real  exception  to  the 
general  rule.  It  is  true  that  these  have  been  found  (as  usual)  in  the 
basin  of  an  extinct  lake,  but  they  have  not  been  found  in  any  lacustrine 
deposit,  but  under  them  all,  in  actual  contact  with  the  sandy  clay  which 
formed  the  original  surface  of  the  valley. 

Furthermore,  they  presented  to  me  the  appearance  of  having 
been  for  a  long  time  knocked  about  among  stones,  whereby  they  were 
much  abraded  and  broken  up  before  they  got  into  still  water ;  the  de- 
tached parts  have  not  in  any  case  been  found,  so  as  to  be  identified. 
They  also  appeared  to  have  been  forced  down  between  the  boulders 
by  some  great  vertical  pressure,  but  not  by  the  gradually  increasing 
pressure  resulting  from  the  slow  accumulation  of  lacustrine  deposits. 
Moreover,  the  stratum  lying  immediately  over  them  did  not  appear  to 
me  to  be  lacustrine  at  all,  but  more  like  the  surrounding  surface  soil, 
and  probably  the  result  of  a  land-slip,  or  flood. 

If  the  above  views  be  correct,  it  appears  almost  certain  that  the 
remains  were  deposited  where  found,  before  the  lake  or  tarn  was  formed; 
for  had  it  existed  even  for  a  short  time  previously,  some  sediment  would 
have  been  formed  beneath  the  bones,  but  there  was  none. 

In  the  next  place  it  excludes  the  possibility  that  the  animals  were 
^'  mired;"  had  they  been  so,  the  remains  would  have  been  found  in  the 
lacustrine  strata,  and  not  entirely  under  them  all,  as  above  described ; 


*  The  exception  above  referred  to  is  the  discovery  of  a  skeleton  in  drift  sand 
(in  1828)  above  the  Enniskerry  liver,  which  is  separated  from  Ballybetagh  by  the 
Scalp  range  of  hills. 


740  Proceedings  of  the  Royal  Irish  Academy. 

and  even  if  we  suppose  the  mud  of  the  lake  to  have  been  sufficiently^ 
fluid  to  pennit  the  bones  to  sink  through  it,  so  as  to  rest  on  the 
bottom,  they  would  touch  it  only  at  three  or  four  points;  tho 
great  mass  of  the  antlers  would  stand  up  off  the  bottom ;  the  sediment 
would  form  under  and  around  them,  and  they  would  be  found  imbedded 
in  lacustrine  clay  or  marl ;  but  they  did  not  in  any  instance  present 
such  appearance. 

It  might  be  supposed  that  they  were  carried  into  the  lake  by  the 
stream  which  flowed  through  it,  and  in  fact  their  shattered  and  water- 
worn  appearance  has  been  thus  accounted  for,  but  they  were  entirely 
out  of  the  course  of  the  torrent,  and  in  a  part  of  the  tarn  near  it» 
margin  that  must  have  been  still  water  from  the  flrst  formation  of 
the  lake. 

The  conclusion  at  which  I  have  arrived  on  this  part  of  the  subject 
is,  that  the  remains  were  deposited  where  found  aU  at  once^  and  before^ 
the  lake  was  formed. 

But  even  though  the  bones  might  be  deposited  all  at  once  where 
they  were  found,  it  does  not  necessarily  follow  that  the  herd  perished 
all  at  once  by  any  sudden  catastrophe.  The  remains  might  have  been 
accumulating  for  many  years ;  but  if  such  were  the  case,  it  is  hardly 
conceivable  that  there  should  nut  be  found  among  them  the  remains, 
of  even  one  female.  Of  the  six-and-thirty  heads  exhumed  aU  were 
males.  I  think  this  one  fact  negatives  the  possibility  of  the  accumu- 
lation extending  over  many  years;  it  is  more  probably  the  result  of 
the  final  extinction  of  the  vast  herd  of  these  noble  animals  that  once 
roamed  over  those  hills. 

The  absence  of  female  remains  has  been  accounted  for  by  the  sup- 
position that  the  herd  perished  by  some  sudden  disease  or  catastrophe 
during  the  season  of  the  year  when  the  males  and  females  heided 
separately,  which  may  be  roughly  stated  as  from  April  to  October.  I 
think  the  suggestion  very  reasonable,  and,  if  true,  the  remains  of  the 
females  are  to  be  found  in  equal  quantities  at  no  great  distance  from 
the  former,  probably  on  the  other  side  of  the  tarn. 

Had  they  perished  while  the  two  sexes  intermingled,  t .  e.^  from 
October  to  March  or  April,  we  might  reasonably  expect  to  find  their 
remains  mixed  in  due  proportions ;  it  seems  to  me  therefore  almost 
certain  that  they  did  not  perish  during  the  winter  months, 

I  think  it  possible,  by  a  similar  method  of  exclusion,  to  fix  the 
season  at  which  they  perished  with  reasonable  probability :  «.  ^.,  among 
the  six-and-thirty  heads  exhumed,  not  one  was  destitute  of  antlers ; 
that  is  to  say,  not  one  of  the  animals  periBlied  during  the  season 
between  the  fall  of  the  antlers  and  their  reproduction,  embracing  May 
and  the  first  half  of  June  ;  not  one  during  the  early  stages  of  growth, 
including  the  remainder  of  June  and  July.  It  would  not  be  possible 
without  microscopical  examination  to  assert  that  none  of  the  antlera 
found  were  in  any  stage  of  growth ;  but  I  hope  during  this  summer 
to  make  such  investigation  as  will  decide  this  question. 


Porte — On  Remains  of  Cervus  Megaceros,  741 

When  the  aatlers  were  fully  grown,  the  males  and  females  mingled 
together  again,  and  the  ratting  season  commenced. 

Some  of  the  remains  present  the  clearest  possible  evidence  that 
the  animals  perished  during  the  fall  of  the  antlers;  that  is  to  say,  daring 
the  latter  part  of  April,  and  part  of  May ;  the  barr  and  constriction 
around  the  base  of  the  antler  marking  the  preparation  for  its  fall  being 
in  various  stages  of  progress,  from  the  first  enlargement  of  the  burr  ; 
almost  to  a  perfect  constriction  :  no  doubt  therefore  can  exist  as  to  the 
season  of  the  gear  at  which  they  perished. 

Of  those  not  thus  marked,  no  certain  evidence  of  time  exists,  except 
that  the  antlers  were  fully  developed  at  the  time  of  death :  I  think  it, 
however,  extremely  probable  that  all  perished  at  the  same  time. 

I  may  observe  here,  once  for  all,  that  in  speaking  of  months  and 
seasons,  I  have  assumed  that  these  were  somewhat  like  what  they  are 
ut  present ;  and  also,  that  the  habits  of  the  great  deer  did  not  differ 
very  much  from  those  of  existing  species. 

Among  the  remains  are  three  or  four  shed  antlers,  but  the  skulls 
to  which  they  belonged  were  not  found,  unless  we  assume  them  to  be 
castings  of  preceding  years. 

It  is  worthy  of  remark  that  the  find  consisted  almost  entirely  of 
heads  and  antlers.  All  the  other  bones  found  with  the  thirty-six  heads 
and  antlers  would  not  be  sufficient  to  build  up  a  single  skeleton ;  but  it 
is  extremely  probable  that  the  smaller  bones  would  be  found  in  similar 
quantities  in  the  central  parts  of  the  valley  answering  to  the  deeper  parts 
of  the  ancient  tarn,  i.  e.,  assuming  the  remains  to  have  been  brought 
there  by  the  agency  of  water. 

There  is  apparently  no  limit  to  the  quantity  of  these  bones  that 
might  be  obtained  if  necessary,  but  I  do  not  see  that  any  useful  end 
could  be  answered  by  exhuming  cartloads  of  similar  remains,  and  in 
the  same  condition ;  but  I  think  that  some  additional  knowledge  of 
this  noble  animal  might  be  obtained  by  exploring  the  opposite  margin 
of  the  valley,  and  also  the  middle  or  deeper  parts,  in  order  if  possible 
to  discover  what  has  become  of  the  herd  of  females,  which  we  may 
assume  did  not  differ  very  much  in  number  from  the  males. 

On  the  whole,  I  do  not  think  the  evidence  at  present  before  us 
would  enable  us  to  decide  where  or  by  what  means  this  magnificent 
herd  became  extinct,  though  we  may  be  able  to  say  with  reasonable 
certainty  where  and  how  they  did  not  perish. 

Were  I  disposed  to  theorise,  I  might  answer  these  questions  with 
reasonable  probability,  but  I  prefer  laying  before  the  Academy  what 
I  oonsideT  proved  facts,  in  order  to  have  them  placed  on  record  for  the 
aid  of  future  explorers  in  this  field  of  science. 


742  Proceedings  qf  the  Boyal  Irish  Academy. 


UX. ^ThB  DETBCTIOir    AND    PbECIPITATIOK    op    PhOSPHOBIC    Acn>     BT 

Amxonic  Moltbdatb.     By  Abchibald  Kichol  M^Alpote,  B.  8c. 
(Lond.),  Royal  Ezhibitioner,  Eoyal  Ck»llege  of  Science. 

[Bead  June  26, 1876.] 

Thb  detection  and  precipitation  of  phosphoric  acid  by  amnionic 
molybdate  has  occupied  the  attention  of  several  chemista. 

Itichters*  has  found  that  the  test  is  rendered  more  delicate,  and 
precipitation  more  rapid,  if  ammonic  nitrate  is  added  to  the  solution 
to  be  examined  for  the  phosphoric  acid  prior  to  adding  the  molybdic 
test. 

From  a  series  of  experiments  I  have  made,  I  find  that  the  test  can 
be  rendered  still  more  delicate,  and  the  precipitation  still  more  rapid, 
if  an  excess  of  ammonic  molybdate,  some  strong  nitric  acid,  and 
finally,  strong  ammonia,  be  added  to  the  solution,  until  it  is  nearly 
neutral.  In  this  way  I  found  phosphoric  acid  in  waters  which  yielde<l 
no  trace  with  the  usual  molybdic  solution  after  standing  at  a  gentle 
heat  for  a  considerable  time. 

In  making  my  experiments  I  noticed  that  molybdic  acid  is  easily 
separated  from  the  larger  portions  of  the  ammonia  with  which  it  is 
combined,  under  certain  conditions;  these  conditions  are  that  the 
solution  should  be  hot,  and  saturated  with  ammonic  nitrate,  and  that 
free  nitric  acid  should  not  be  present  in  excess.  It  may  be  that  the 
greater  delicacy  of  the  test,  in  a  phosphate  solution  containing  nitric 
acid  to  which  ammonia  has  been  added  to  near  the  neutral  point,  is 
due  to  the  formation  of  this  acid  molybdate,  which  combines  with  tho 
phosphoric  acid  to  form  the  ammonio-phospho-molybdate  precipitate. 

I  then  made  some  experiments  to  determine  the  effect  of  nitrii; 
acid  on  the  precipitation.  I  found  that  beyond  a  certain  point  nitric  acid 
hindered  the  precipitation  in  very  dilute  phosphate  solution,  and 
generally  it  retarded  the  formation  of  the  precipitate.  This  is  contrary 
to  the  statement  made  in  some  of  the  works  on  chemical  analysis. 

To  determine  good  proportions  for  the  ammonia  and  nitric  acid, 
I  made  various  experiments  with  10  cubic  centimetre  portions  of  a 
phosphate  solution  containing  *OlO  grammes  of  phosphoric  acid  per 
litre,  varying  the  quantities  of  nitric  acid  in  the  different  experimenta. 
I  added  ammonia  to  the  solution  until  the  precipitate  formed  most 
favourably,  and  finally  I  determined  the  amount  of  free  acid  remaining 
in  the  solution.  I  found  the  following  proportions  made  the  test  the 
most  sensitive : — 


*  Sec  Dingl.  Polyt.,  J.  cxcix.  183 ;  also  vol.  24  Chem.  Soc.  JoamaL 


M*  Alpine — Precipitation  of  Phosphoric  Acid.  743 

60  grammes  Ammonic  Molybdate. 
500  cc.  !Nitric  Acid  (sp.  gr.  1-4). 
400  cc.  Ammonia  (sp.  gr.  '96). 
400  cc.  Water. 

A  solution  containing  these  proportions  gives  an  immediate  pre- 
cipitate if  added  to  10  cubic  centimetres  of  a  phosphate  solution  con- 
taining 'Ol  grammes  of  phosphoric  acid  per  litre. 

I  next  tried  the  effect  of  hydrochloric  acid .  on  the  precipitation. 
For  this  purpose  I  employed  10  cubic  centimetres  of  a  solution  con- 
taining '01  grammes  of  phosphoric  acid  per  litre,  3  cubic  centimetres  of 
the  ordinary  laboratory  solution  of  ammonic  molybdate,  and  2  cubic 
centimetres  of  strong  hydrochloric  acid.  There  was  no  precipitijte 
alter  shaking  and  allowing  to  stand  for  some  time,  but  on  adding  am- 
monia a  precipitate  was  produced  which  was  not  so  rapid  in  its  forma- 
tion, nor  so  copious  as  when  nitric  acid  was  present. 

I  now  tried  to  obtain  a  volumetric  test  for  phosphoric  acid.  To 
avoid  the  necessity  of  adding  excess  of  ammonic  molybdate,  I  added 
to  the  solution  sodic  molybdate,  which  does  not  precipitate  the  phos- 
phoric acid,  and  then  ammonic  molybdate.  Eor  example,  I  took  50 
cubic  centimetres  of  a  solution  of  phosphate  of  soda  containing  excess 
of  sodic  molybdate.  5cc.  of  ammonic  molybdate  appeared  to  precipitate 
the  phosphoric  acid  completely,  as  the  further  addition  of  ammonic 
molybdate  to  a  portion  of  the  filtered  solution  gave  no  precipitate  on 
heating,  nor  the  reaction  for  ammonic  molybdate  on  adding  phosphate 
solution.  Thus  it  appears  that  by  using  an  excess  of  sodic  molybdate, 
the  necessity  for  an  excess  of  ammonic  molybdate  is  avoided.  I  made 
various  other  experiments  in  this  way,  and  it  seems  as  if  there  was  a 
point  at  which  the  precipitation  of  the  phosphoric  acid  is  complete, 
and  no  ammonic  molybdate  in  solution. 

Lastly  I  substituted  for  the  ammonic  molybdate  ammonic  nitrate, 
which  I  added  to  the  phosphate  solution  containing  excess  of  sodic 
molybdate,  and  here  also  there  appeared  to  be  a  point  where  the  pre- 
cipitation of  the  phosphoric  acid  was  complete,  and  no  ammonia  in 
solution. 

I  now  attempted  to  determine  the  point  of  complete  precipitation  in 
various  ways,  but  I  could  find  no  convenient  way  of  determining  the 
exact  point,  when  all  the  ammonia  as  well  as  the  phosphoric  acid  had 
been  precipitated. 


744  Proceedings  of  the  Royal  Irish  Academy. 


LX. — Ok  a  Cebtaik  Rklatiok  bbtwxsk  the  Quadeatic  ExPBSssioir 
Q*  -  3PP',  AND  THB  Product  op  the  SauAEEs  of  the  Diffeeekcz^ 
OF  the  Roots  of  a  Cubic  Equation.  By  J.  E.  Young,  formerly 
Professor  of  Mathematics  in  Belfast  College. 

[Read  June  26,  1876.] 

Let  a?Jcpx'^q  =  0  (I) 

be  the  equation  which  results  from  depriving  the  cubic  equation, 

a^-^A^-^AiX^J^^Q  (2) 

of  its  second  term  ;  that  is,  let  (1)  be  the  equation  which  arises  from 

diminishing  each  of  the  roots  of  (2)  by  -  -  ^s ;  then,  conformably  to 

3 

the  notation  of  my  former  Papers, 

P  =  «*  +  |>iF  +  y 

Q  =3«»+^  .-.  <?  =  9;i:*  +  6i»j? +!>» 

2^  =  30?  3PP'=94;*+9j»a:»  +  9^ar 


•.  (?-3PP  =  -3pji»-9^a?+^. 


19'ow,  the  square  of  the  middle  co -efficient  of  this  quadratic  ex- 
pression, diminished  by  four  times  the  product  of  the  extremc^ 
co-efficients,  furnishes  the 

Remainder,  81^  +  12^  =  3  (27^  +  Ap')  ; 

which  (with  changed  sign)  is  three  times  the  product  of  the  squares  of 
the  differences  of  the  roots  of  the  equation  (1).  {Theory  and  Solution 
of  EqtMtionSf  p.  410).     [This  is  proved  independently  at  the  end]. 

But  the  differences  of  the  roots  of  the  equation  (2)  are  the  same 
as  the  differences  of  the  roots  of  the  equation  (1) ;  because  the  roots 
of  (2)  are  no  other  than  the  roots  of  (1),  each  increased  by  the  same 

quantity  ;  namely,  by  the  quantity  -  -  A^. 

3 

Calling  this  quantity  a,  the  equation  (2)  is 
(ar  +  fl)'  +1? ( a:+  a)  +  ^  =  0  ; 
and  the  expression  ^  -  3PP,  for  this  equation,  is 
<?-3PP'  =  -3p(a:  +  a)»-9^(a?  +  fl)+i>« 

=  -  3|?^  -  (6pfl  +  9^>  -  Zpa^  -  9^fl  4-i?'. 


TouNG — Product  of  the  Squares  of  the  Differences^  etc.   74i 
The  square  of  the  middle  co-efficient  here  is 

and  4  x  the  prod,  of  the  extremes,    36j9*a*  +  lOSpqa  -  12^ 


.'.  the  remainder  is  81y'+  12^, 

which,  as  might  have  heen  anticipated,  is  the  same  as  the  remainder 
ahoye ;  and  the  remainder  would  still  he  the  same  whatever  he  a. 
If  we  represent  the  expression  Q?  -  SPP'  by  Ax^  +  Bx+Cf  and  tho 
roots  of  the  equation 

by  n  and  rj,  then  will 

^i  "  4  2"  "  ^'"^  "^  ''*^'  -  4ri  rs  =  (ri  -  r,)' ; 

and  therefore, 

B'-'AAC^A\r,-'rt)\  (3) 

Hence,  the  square  of  the  difference  of  the  two  roots  of  the  quad- 
ratic equation  ©*  -  ZPF'  =  0,  multiplied  by  ^',  is  equal,  when  its  sign 
is  changed,  to  three  times  the  product  of  the  squares  of  the  differen- 
ces of  the  roots  of  the  cubic  equation  (2).  We  deduce,  moreover,  the 
conclusions  following,  namely : — 

1.  If  ^  =  ^ACf  that  is,  if  the  two  roots  r^  r%,  are  eqtud  roots, 
then  also  two  roots  of  the  cubic  equation  (2)  must  be  equal  roots, 
seeing  that  ondj  at  least,  of  the  differences  furnished  by  the  three 
roots  must  then  be  zero.  These  latter  equal  roots  must  be  the  same 
as  the  former  (ri,  Vi) :  for,  representing  one  of  the  equal  roots  of  (2) 
by  r,  the  expressions  Q*,  and  ZFF',  must  each  be  divisible  by  {x-r)^  \ 
and  consequently, 

<?-  SPP',  that  is,  Ajx^^Bx^C 

must  also  be  divisible  by  (ar-r)'.  But  this  expression  (under  the 
stipulated  condition,  namely,  the  condition  ri  =  r,),  is  divisible  by  no 
quadratic  factor  other  than  (a? -  ri)' ;  therefore,  x-r  and  x-ri  must 
be  identical :  hence  the  equations  P  =  0  and  Q*  -  SPP'  =  0  must 
have  the  same  pair  of  equal  roots.  [When  all  the  roots  are  equal, 
Q*  =  3PP' ;  and  there  is  no  remainder]. 

2.  If  B^>AACy  that  is,  if  the  roots  ri,  rs,  of  the  equation 
Q*-3PP'  =  0  are  real  and  unequal,  the  sign  of  B^-^AC  will  be 
plus :  and  therefore  the  sign  of  the  product  of  the  squares  of  the 
differences  of  the  roots  of  the  equation  P  =  0,  or  (2),  must  be  minus  ;■ 
which  can  be  the  case  only  when  P  =  0  has  a  pair  of  imaginary  roots. 
Whenever  C  is  minw  (the  co-efficient  A  being  plus\  the  sign  of 
B^-AAC  will  necessarily  he  plus;  as  also  when  C  is  zero.  The  sign 
must  also  be  plus  whenever  A  and  C  are  both  minus  ;  since  if,  under 
these  conditions,  B^-^AC  could  be  minus,  the  roots  of  Q^  - 3PP  =  0 


746  Proceedings  of  the  Royal  Irish  Academy. 

would  be  imaginary ;  and  therefore  (haying  regard  to  the  prefixed 
minus  fdgn)  the  expression  Q*  -  ZPP  would  be  negative,  whatever 
real  value  be  given  to  x.  But  for  that  value  of  x  which  makes 
P  =  0,  as  also  for  that  which  makes  P  -(i^  this  expression  is  posi- 
tive ;  hence  it  is  impossible,  in  the  case  supposed — ^the  case,  namely, 
in  which  A  and  C  are  both  minus^  that  the  sign  of  j^  -  AA  C  can  ever 
bo  minus.  Whenever,  therefore,  C  is  minus,  whichever  be  the  sign 
of  A,  the  equation  P  =  0  must  have  a  pair  of  imaginary  roots. 

3.  If  £^<AAC,  that  is,  if  the  roots  n,  r„  of  <?-  SPP'  =  0,  are 
imaginary,  the  sign  of  jB* -  4-4 6' will  be  minus;  and  therefore,  the 
sign  of  the  product  of  the  squares  of  the  ditfercnces  of  the  roots  of 
(2),  or  P  =  0,  must  be  plus^  which  can  be  the  case  only  when  all  the 
roots  of  P  =  0  are  real. 

And  in  this  way  are  established  the  theorems  arrived  at  in  a  very 
different  manner  in  my  Paper  **  On  the  Imaginary  Roots  of  Numeri- 
cal Equations."*  The  theorems  themselves,  as  here  arrived  at, 
{ire  but  so  many  inferences  from  the  property  which  it  was  the  main 
purpose  of  this  communication  to  prove,  namely,  as  shown  above, 
that 

A^     ' 
or,  which  is  the  same  thing,  that  (ri  ~  i^}^  is  equal  to 

where  i?i,  Ri^  i?3,  are  the  three  roots  of  the  cubic  equation  P=0, 
and  Ti,  f},  are  the  two  roots  of  the  quadratic  equation 

<?-  ZPP  =  0,  or  Ax^-^Bx-^  C=  0, 

deduced  from  this  cubic.  And  although  particular  examples  are 
never  necessary  to  verify  a  demonstrated  general  truth,  yet  as  such 
examples  are  often  acceptable  illustrations  of  theory,  I  shall  here 
subjoin  one  or  two. 

1.  The  roots  of  a:*+  10j:»  +  31:f+  30  =  0  are 
-2,-3,-5; 
and  the  expression  Q^-SPP  is 

.-.  i9»  =  40»=  1600,  and4^r=4x7x61  =  1708, 

— 108 
and  the  difference,  i?*  -  4-4  C,  is  -  108,  and  —5—  -  -  36. 

3 

The  differences  of  the  roots  of  the  equation  are 
-2+3,-2  +  6,  and-3  +  5; 


Vide  Proceedings  R.  I.  Acad.,  vol.  z..  Series  I.,  p.  343  (1866^9). 


TouNO — Product  of  the  Squares  of  the  IHfferences,  etc.     747 

the  squares  of  which  differences  arc 

1',  3',  2' ;  and  the  product  of  these  is  86 ; 
and  the  former  result,  when  its  sign  is  changed,  is  the  same  number. 

2.  The  roots  of  ic'^  4^;*  +  Or  +  2  =  0  arc 

2,  1  +  V2,  1-V2; 

and  the  expression  Q"  -  ^PP  is 

^«»  +  ^;p+  C=7a^-30a?  +  33; 
.-.  B^  =  900,  and  4^C  =  924  ; 

.-.  J9=»-4-4C=-24;  nnd~  =  -8. 

The  differences  of  the  roots  are 

1-V2,  1+V2,  2V2; 

and  the  product  of  these  differences  is  -  2\/2,  of  which  product  the 
square  is  8  ;  the  same  as  the  former  result  when  its  sign  is  changed. 

3.  It  may  be  well  to  work  out  this  final  example  in  more  detail : 

P  =  a:3+ii^_102a?  +  181  =0 
C  =  3«»  +  22a?-102 
2^  =  32?+ 11. 

Multiplying  Q  by  itself,  and  omitting  terms  in  a?  and  ^, 
3ar»  +  22a?-102 
3a:»  +  22a:-102 


4842^  -  612;r2  -  4488^:  +  10404 
.-.  <?  =  -128ir»- 4488a? +10404. 
In  like  manner,  multiplying  P  by  -P, 

a:'  +  lla^-102j?+181 
3a?+ll 


121ar»-306.r*- 1122J?  +  543ar  +  1991 

=  -  185^;*  -  579a?  +  1991  =  PP 

<?-3PP'  =  427*2 -275U  + 4431  ^Ax'-^Bx^C; 

.'.  JB^  =  7568001 
4  ^C=  7568148 


-447  =  ^-4^C7. 


748  Proceedings  of  the  Royal  Irish  Academy, 

Therefore  three  times  the  product  of  the  squares  of  the  differences  of 
the  roots  of  the  equation  P  =  0  is  -f  147.     Also 

r„  r,  heing  the  two  roots  of  427*"  -  2751i:  +  4431  «  0. 

These  two  roots  would,  of  course,  remain  unaltered,  although 
the  co-efficients  of  the  equation  Aa^  +  Bx  +  C=  0  were  each  multiplied 
or  divided  by  any  number ;  but  the  numerical  result,  -B*  —  A  A  C,  would 
be  changed  by  such  multiplication  or  division,  and  would  no  longer 
express  three  times  the  pzx)duct  of  the  squares  of  the  differences  ol 
the  roots  of  P  =  0.  The  aip^  of  the  numerical  result  would,  however, 
be  the  same;  and  therefore,  for  the  purpose  of  ascertaining  the 
character  of  the  roots  of  the  cubic  equation  P  =  0,  the  co-efficients  of 
the  quadratic  equation  Q*-3PP'=0  may  always  be  reduced  to 
smaller  numbers  whenever  they  have  a  common  factor.  Thus,  in  the 
present  example,  we  see  that  the  co-efficients  in  the  expression 
Q*  -  3PP  are  each  divisible  by  the  number  7 ;  so  that  we  may 


write 


and  thus  get 


61.t»-  39ac  +  633  =  A'x^-^B'x^-  C, 
61«»  -  393ir  +  683  =  ^V  +  P'o:  =  (7, 


Bn  -.  ^A'a  =  15449  - 154462  =  -  3  ;  axid  —  =(ri  -r,)«; 

-  147 

this  last  result  being  the  same  as        ^  =(ri~ra)*. 

It  is  obvious  that  if  iT  denote  the  number  by  which  each  of  the 
co-e£^cients  -4,  B,  C,  is  divided,  in  any  case,  JT*  times  B^  -  4AC 
win  be  equal  to  B*  -  4AC ;  that  is  (changing  the  sign),  to  three  times 
the  product  of  the  squares  of  the  differences  of  the  roots  of  the  equa- 
tion P  =  0 ;  in  which  equation,  it  is  to  be  observed  that  the  coeffi- 
cient of  a^  is  unity  ^  If  the  co-efficient  of  ^,  in  the  proposed  cubic 
equation,  be  A^,  a  number  different  from  unity,  then  it  is 

2Ji  K^i  -  '^lA  0' j-i 9 

which,  with  changed  sign,  is  equal  to  three  times  the  product  of  the 
squares  of  the  differences  of  the  roots  of  the  cubic  equation ;  that  is, 
<A  the  equation 

P  =  A^x^  +  Aj^  -f  Aix  +  ^0  ==  0 ; 

because  the  co*cfficients  A,  P,  C,  as  deduced  from  this  equation,  bi^ 
each  A^  times  what  they  would  be  if  the  co-efficient  of  «*  were 


TouNG — Product  of  the  Squares  of  the  Differencee^  etc.    749 

reduced  to  nnity  by  the  terms  of  the  equation  being  each  of  them 
divided  by  A^, 

Take,  for  instance,  the  equation  following : — 

P  =  2:r»  -  3a;>  -  Tar  +  5  =  0, 

-one  of  the  roots  of  which  is  found  to  be  2*5  {Analysis  and  Solution  of 
Cubie  and  Biquadratic  Equations,  p.  179).  To  obtain  the  remaining 
roots  we  proceed  thus  : — 

2 -3-7 +  6  (2-5 
5     6:- 6 

2-2    0  .-.  2a:*  4  2j:  -  2  =  0,  or  ar»  +  a:  -  1  =  0, 
^hich  equation  giyes,  for  the  other  two  roots  of  the  equation  P  =  0, 

so  that  the  product  of  th^  squares  of  the  differences  is 

Again:   <?-3PP'  =  ^«»  +  -ffa:+ C=51«»-69ic+94;  therefore, 
B'-AAC     4761-19176     -14415 


16  16 


(2) 


und,  changing  the  sign  of  this,  (l)x3  =  (2). 

The   square  of  the  dilference  of  the  two  roots  ri,   rs,  of  the 
equation 

Ax^^^Bx^C^O 
is  of  course  • 

_    va_  B*'4AC     69»-204x94      -14415 


which,    multiplied   by   -j^,    that  is,  by  — ,    gives    — ^ — ,     the 


^'      XI.  ^  •     v     51'       .        -  14415 
--,    that  IS,  by-,    gives    -^ 

same  result  as  that  marked  (2)  above;  and  which,  by  the  expres- 
sion (1),  is  three  times  the  product  of  the  squares  of  the  differences 
of  the  roots  of  the  equation  P»  0,  when  the  sign  of  this  product  is 
changed. 

It  may  not  be  superfluous  to  remark  here,  that  the  relation 
established  in  this  Paper  between  the  product  of  the  squares  of  the 
three  roots  Bi,  jRj,  i^,  of  a  cubic  equation, 

P=^a«>  +  ^,r3  +  ^,ar  +  ^  =  0, (1) 


750  Proceedings  of  the  Royal  Irish  Academy. 

and  the  square  of  the  difference  of  the  two  roots  ri,  rs,  of  the  quadiatie 
equation 

<?-3Pi>'«0;  thatis,  of-4«'  +  j5j?+  C=0, (2) 

the  relation — ^namely, 

jl  (r,-r,)'  =  ^:^=-3(i?.-i?.)»(JZ,-J?,)'<J?,-J?,)«, ....  (3) 

can  subsist  only  when  the  equation  Q*  -  SUP  =  0  has  two  roots ; 
that  is  to  say,  only  when  ^  is  a  significant  number.  If  ^  be  teroj  the 
equation  (2),  being  then  of  only  the  first  degree,  has  but  one  root, 
and  the  first  member  of  (3)  is  nugatory ;  but  the  second  member  re> 
mains  significant ;  it  is  B^^A^.  But  if  C7  be  zero,  and  A  a  signi- 
ficant number,  one  root  (r,)  of  the  quadratic  equation  will  be  zero  ; 
and  the  first  and  second  members  of  (3)  will  then  be 

— ,r,,and— , 

implying  that  when  the  quadratic  equation  Q*-  3PP'  =  0  is 

Ax'-k^Bx^Q, 

three  times  the  product  (with  changed  sign)  of  the  squares  of  the  differ- 

B^ 
cnces  of  the  roots  of  (1)  is  equal  to  — -,  or  simply  to  B^,  or  -4Vi*,  if 

the  co-efficient  -4 j,  in  (1),  is  unity. 

For  example  :  suppose  we  have  the  equation 

P  =  ar»+3iB»-6x  +  4  =  0, 

where  the  second  triad  of  co-officicnts  furnishes  the  condition 

^i'-3A^s  =  0. 

The  equation  Q*  -  ^PF  =  0,[here,  is  found  to  be 

Ax^  ^Bx+C=  27af»  -  54ar=  0  ; 

in  which  the  values  of  ar  are  a?  =  0,  and  ^  =  ri  =  2. 

Now,  if  each  of  the  roots  of  the  equation  P=  0  be  diminished  by 
>  1,  the  second  term  will  disappear  in  the  transformation,  which  will 
be  the  equation 

a:»-9^+12  =  0; 

and  the  product  of  the  squares  of  the  differences  of  the  roots  of 
this  equation,  when  the  sign  of  that  product  is  changed,  is  (by  p.  410^ 
Theory  of  Equation)  4^  +  27^*,  where,  in  the  present  case,  ii  =  -9. 


TouNG — Product  of  the  Squares  of  the  DiJfereneeSj  etc.   761 

and  ^  =  12.  Hence,  three  times  the  prodnct  of  the  squares  of  the  dif- 
ferences of  the  roots  of  P=  0  is 

(- 2916  + 3888)  X  3  =  2916  =  54«  =  ^  =  ^Vi«. 

If  A  and  C  be  each  of  them  zero,  then  B  itself  will  be  zero ;  and 
P  will  be  a  complete  enbe,  or  a  complete  cube  multiplied  by  a 
numerical  factor.  It  was  shown  in  my  Paper  (read  November  9, 
1 868)  that  P  being  A^  -i-  J^  +  A^x  +  Ao,  (?  -  3PP  is 

(^a«  -  3^1-43)  x"  +  {AiA2  -  9^o^s)  x+(Ai^-  SAoAi) ; 

and  that  the  two  conditions 

-4,»  -  ZA^Ai  =  0,  and  A^^  -  SA^At  =  0, 

necessitate  the  third  condition 

AiAt-dAoA^^O, 

will  be  seen  by  transposing  the  minus  term  of  each,  and  then  multi- 
plying the  results  together ;  for  we  shall  thus  have 

and,  consequently, 

SO  that,  when  the  two  foregoing  conditions  hare  place,  the  expres- 
sions ^  and  ^PP  must  be  identical;  and,  therefore,  P  must  be 
of  the  form  A^  {x  +  a)'. 

I  shall  now  give  a  simple  and  direct  proof  of  the  property  referred 
to  (already  otherwise  cstabUBhed)  at  the  commencement  of  the  pre- 
sent Paper — namely,  that  if  D^  represent  the  product  of  the  squares  of 
the  difEerences  of  the  roots  of  the  equation 

a^^px-\-q=  0  .  .  .  .  (1), 
we  shall  always  have 

2?»  =  -(27i?»+4^). 

Demonstration, — It  is  shown  in  the  Theory  of  JEqitations,  p.  822, 
that  if  Xi  be  either  of  the  roots  of  the  equation  (1),  all  three  of 
the  roots  will  be 

Kow,  the  differences  of  these  are 


;*.-v(-3^-;,y|x.w(-3^|-/»).2v(-3^-i,)....(2), 


3 

2' 

B.  I.  A.  PBOC,  SBIU  II.,  TUL.  U.,  8CIBICCI.  3  T 


that  is, 


that  is, 


752  Proeeedingi  of  the  Royal  Iruh  Academy, 

and,  therefore,  the  product  of  the  squares  of  the  differences  is 

(3xi«+i>)»(3x»»  + 4;,)  =  -!;», 

or, 

27jr,»  +  54pari*  +  21  fx,^  +  4/  =  -  i/*, 

But  by  the  equation  (1),  (a?i*  +  pxi)'  =  y' ;  therefore, 

i>»  =  -  (27^  +  4j^). 

From  the  foregoing  results  we  may  deduce  the  equation  of  which 
the  roots  are  the  squares  of  the  differences  of  the  roots  of  the  equa- 
tion (1),  with  remarkable  facility,  thus : — Let 

represent  the  equation  of  which  the  three  roots  are  the  squares  of 
the  three  expressions  (2),  in  which  expressions,  Xi  is  either  one, 
indifferently,  of  the  three  roots  of  the  equation  (1).  Then  the 
co-efficient  a  will  denote  the  sum  of  the  squares  of  the  three  ex- 
pressions (2),  when  the  sign  of  each  square  is  changed ;  the  co- 
efficient h  will  denote  the  sum  of  the  products,  taken  two  and  two,  of 
these  same  squares,  whether  the  signs  of  them  be  changed  or  not, 
since  the  resulting;  products  are  the  same;  and  c  will  denote  the 
product,  with  changed  sign,  of  all  three  of  the  squares. 

Kow,  each  of  these  co-efficients  has  but  a  single  definite  value ;  so 
that  no  quantity  involying  Xi  (which  has  a  threefold  value)  can  enter 
any  of  them,  except,  indeed,  tiie  quantity  be  of  the  form 

where  n  is  a  whole  number,  and  m  a  numerical  factor ;  because  onlj 
then,  and  when  ^i  is  entirely  absent  (in  consequence  of  the  tenns 
involving  Xi  neutralising  one  another),  can  the  co-efficients  0,  i,  c, 
have,  each  of  them,  single  unambiguous  values. 


Young — Product  of  the  Squares  of  the  DifferenceBj  etc,   753 

It  is  plain,  from  inspection,  that  the  sum  of  the  equaree  of  the 
expressions  (2)  cannot  involve  x^ ;  therefore,  this  sum  must  be  the 
same  as  it  would  be  if  Xi  were  zero ;  that  is  to  say,  the  sum  is 

W  "Pf  +  (v^  -P?  +  4  (V  -pf  =  -  6p  .-.  a  «  6p. 

Again :  the  sum  of  the  products,  two  and  two,  of  the  squares  of  the 
expressions  (2),  cannot  involve  Xi\  seeing  that  the  middle  term 
(the  term  involving  V),  in  the  square  of  the  first  expressions  (2), 
is  the  same,  with  opposite  sign,  as  the  middle  term  (the  term  in- 
volving V),  in  the  square  of  the  second  of  the  expressions  (2). 
Hence,  if  each  of  these  squares  be  multiplied  by  the  square  of 
the  third  of  the  expressions  (2),  and  the  two  products  be  added  toge- 
ther, the  terms  involving  V  will  disappear ;  and  the  result  will  involve 
only  even  powers  of  Xi.  And  it  has  been  already  shown  that  the  pro- 
duct of  the  squares  of  the  first  and  second  of  the  expressions  (2) 
is  (3a:,*  ^pf ;  which,  in  like  manner,  contains  only  even  powers  of  Xi. 
Therefore,  the  sum  of  the  three  products  must  be  the  same  as  it  would 
be  if  Xi  were  zero ;  that  is  to  say,  the  sum  of  the  products  is 

and  it  has  been  already  proved  that  the  product  of  all  the  squares  is 

-  (27^  +  4p^),  .-.  e  =  27q*  +  4^. 
Consequently,  the  equation  of  the  squares  of  the  differences  is 

s»  +  6jw»  +  9ph  +  4y  +  27q*  =  0, 
the  equation  which  Lagrange  has  arrived  at  in  a  very  different  manner. 

l^Note  added  in  Press. — The  following  somewhat  remarkable  truth  is 
an  immediate  inference  from  Article  (12)  in  my  last  Paper,  namely : — 

In  a  cubic  equation  of  which  the  roots  are  real,  although  each 
root  of  the  derived  quadratic  always  lies  between  two  roots  of  the 
cubic,  yet  it  is  impossible  that  either  of  the  two  roots  of  the  qua- 
dratic can  ever  lie  midway  between  the  two  neighbouring  roots  of  the 
cubic] 


764  Proceedings  of  the  Royal  Irish  Acadefi}y. 


LXI. — Oir  A  Nxw  Gew8  A2n>  Species  of  Spoitos.  By  Ed.  Psbcetu 
Wright,  M.  A.,  M.  D.,  F.  L.  S.,  Professor  of  Botany  and  Keeper 
of  the  Herbarium,  University  of  Dublin.     (With  Plate  40.) 

[Read  May  8,  1876.J 

While  working  over  the  very  large  and  valuable  collection  of  Algae 
which  is  under  my  care  in  the  Herbarium  of  Trinity  College,  my  atten- 
tion has  often  been  attracted  by  the  large  number  of  animal  remains, 
to  be  seen  either  adherent  to  or  nestling  among  the  fronds  of  certain 
species.  Not  to  allude  to  a  vast  number  of  species  of  Polyzoa,  which 
are  often  endophytic  to  such  an  extent  as  to  render  the  species  of 
Alg»  impossible  to  be  determined ;  species  belonging  to  the  Pycno- 
gonidiB,  ZoanthidsB,  &c.  are  often  very  numerous,  and  sometimes  large 
numbers  of  sponges  and  foraminifera  will  be  met  with. 

Of  the  sponges,  the  species  as  a  rule  belong  to  forms  with  cither  a 
calcareous  or  a  homy-fibrose  framework :  very  rarely,  and  then  only  at 
the  root-like  extremities  of  some  of  the  larger  forms,  have  I  met  with 
siliceous  sponges. 

The  little  form  that  I  venture  to  describe  here  as  new  was  ^i^ 
known  to  me  from  observing  portions  of  its  stem,  as  in  figure  3,  Plate 
40,  often  without  a  trace  of  any  body  portion,  and  at  a  glance,  and 
using  only  a  hand  lens,  I  thought  it  must  belong  to  some  novel  penta- 
crinoid  form.  A  closer  examination  showed  the  fibrous  nature  of  the 
stem  portion,  and  after  a  while  more  or  less  perfect  specimens  were 
discovered,  which  left  no  doubt  but  that  they  belonged  to  a  sponge. 
A  careful  microscopical  investigation  showed  that  there  were  no 
spicules,  but  it  will  be  recollected  that  I  had  nothing  but  the  well 
dried  and  often  flatly  pressed  specimens  to  examine  ;  still  these  were 
found,  for  the  most  part,  on  species  of  Dclcsseria  which  had  been 
freshly  gathered  by  Professor  Harvey  on  the  Australian  shores,  and  it 
is  not  very  probable  that  any  large  portion  of  the  substance  of  the 
sponge  haii  disappeared.  A  few  siliceous  spicules  were  now  and  then 
to  be  seen,  but  evidently  got  to  be  entangled,  as  foreign  bodies,  in  the 
sponge  mass. 

The  following  may  serve  as  a  diagnosis  of  the  genus : — 

Eallispongia,  gen.  nov. 

Sponge  substance  keratose,  consisting  of  three  distinct  and  well- 
marked  portions ;  firstly,  a  small  basal  disk ;  secondly,  an  elongated 
stem,  on  the  summit  of  which  expands  the  third  portion  or  capitulum. 
The  disk  is  button-shaped,  flat,  and  is  formed  of  an  irregular  horny 
framework,  twice  to  three  times  as  broad  as  the  stem.  The  stem  van^^ 
in  height,  and  presents  the  appearances  in  some  cases  of  a  series  of 
margined  rings,  some  twenty  in  number,  fastened  together  one  on  the 
top  of  the  other ;  in  others  the  margins  of  the  rings  will  be  more  pro- 


Wright — On  a  New  Genus  and  Species  of  Sponge.      765 

minenty  and  the  bodies  of  the  rings  will  be,  as  it  were,  more  deeply 
sunk.  In  both  these  cases  the  homy  framework  is  of  a  more  or  less 
evenly  latticed  character,  the  longitudinal  lines  of  the  lattice  being 
very  prominent. 

The  head  portion,  in  its  natural  state  must,  I  think,  present  a  more 
or  leBB  spherical  form,  perhaps  slightly  flattened  on  the  summit,  with  an 
indication  of  being  divided  into  four  nearly  equal  parts — the  open 
space  between  these  leading  into  the  body  cavity  of  the  sponge.  In  some 
of  the  specimens  the  head  portion  nearest  to  the  stem  seems  to  have 
been  formed  of  a  somewhat  denser  framework  than  the  upper  portion, 
so  that  while  being  pressed  this  upper  portion  has  been  fractured 
across  {vide  fig.  1 ).  The  framework  here  is  of  a  densely  reticulated 
kind,  in  appearance  reminding  one  of  the  reticulated  network  of  the 
intracapsular  sarcode  in  Thalassolampe,  or  of  the  tissues  met  with  in 
some  Echinoderms. 

KdUi^ongia  Areherif  sp.  nov. 

The  description  of  the  genus  will,  for  the  present,  serve  for  the 
species ;  specimens  vary  from  two  to  thi*ee  millimetres  in  height. 

Localities — growing  on  the  fronds  of  various  species  of  Florideae ; 
gathered  on  the  coasts  of  Australia  by  Professor  W.  H.  Harvey,  aboi^t 
1854. 

The  beauty  and  novelty  of  this  little  sponge — the  largest  specimens 
measure  but  three  millimetres  in  height — must  plead  my  excuse  for 
publishing  a  description  of  a  form  that  may  possibly  turn  out  to  be  but 
a  very  young  stage  of  some  other  species. 

It  is  true  that  it  is  by  far  the  smallest  of  all  known  keratose 
sponges,  but  I  do  not  think  that  its  size  necessarily  militates  against 
the  possibility  of  its  being  a  good  species.  Why  should  there  not  be 
very  minute  keratose  as  well  as  very  minute  calcareous  sponges  ?  and 
although  I  did  once  before,*  perhaps  somewhat  prematurely,  describe  a 
young  stage  of  a  siliceous  sponge,  now  that  its  mature  form  is  well 
known,  I  perceive  that  the  difference  between  the  young  and  adult 
form  has  not  been  so  great  as  to  suggest  the  idea  of  there  being  a 
change  or  metamorphosis,  such  as  one  might  a  priori  have  expected,  in 
the  group  of  the  sponges. 

Kallispongia  Archeri  appears  to  me  too  to  have  a  rather  fixed  and 
definite  physiognomy,  and  I  can  easily  fancy  its  going  through  all  the 
phases  of  its  life  history — this  being  the  persona-stage,  amid  the 
thallus  of  its  fostering  alga — after  the  manner  of  some  of  the  mi- 
nute calcareous  sponges  described  by  Haeckel. 

One  very  marked  variety  of  stem  outline  (fig.  3)  I  have  met 
with;  it  forms  a  very  exquisite  microscopical  object.  The  stem  puts 
one  in  mind  of  the  string  of  frustules  of  a  Melosira  or  of  Didynioprium 

*  Quarterly  Journal  of  Microscopical  Science^  January  1870,  p.  1,  PL  2. 


756  Proceedings  of  the  Royal  Irish  Academy. 

Brebissonii  among  tlie  Desmids.  The  basal  ^isk  and  capitolom  seem 
to  difPer  in  no  respect  from  the  typical  form,  and  until  some  time  or 
other  the  species  can  be  examined  in  a  living  state,  this  may  be  re- 
garded as  a  variety  of  the  above  described  form. 

The  species  I  have  named  after  my  friend  William  Archer,  F.  R.  8., 
BO  well  known  for  his  researches  among  the  lower  forms  of  vegetable  and 
animal  life.  His  researches  among  the  Khizopods  are  of  such  valiie, 
that  one  could  wish  that  he  would  extend  them  to  animals  one  step 
l&igher  in  the  scale,  and  so  favour  science  with  a  series  of  observations 
on  the  sponges. 

The  wonderful  mimetic  resemblance  which  this  new  species  bears  to 
some  of  the  stages  of  development  of  a  Crinoidcan  scarcely  be  overlooked. 
Leaving  the  texture  and  composition  of  the  skeleton  mass  for  the  pio- 
ment  out  of  view,  and  simply  looking  at  its  outline — ^the  circular  didc- 
like  base — ^the  stem — the  profile  of  which  is  absolutely  the  same,  except 
as  to  size,  as  that  of  the  pentacrinoid  stage  of  Antedon  rosaceus,  and 
the  slightly  cleft  head,  the  resemblance,  to  my  mind,  is  very  great. 
Of  cen,  indeed,  have  I  been  obliged  to  look,  and  look  again,  and  to 
crush  down  the  specimen,  before  I  could  convince  myself,  by  a  full  view 
of  its  texture,  that  I  was  not  deceived.  So  far  as  I  know,  this  is  a 
unique  case  among  the  sponges,  and  one  is  let  to  wonder  what  may 
be  the  tiny  enemies  from  which  Kallispongia  Archeri,  by  this  complete 
disguise,  conceals  itself. 


INDEX 


TO  VOLUME  n.  OP  THE  PROCEEDINGS. 


Abibs,  reTision  of  the  speoies  of,  673. 

amabilifl,  Douglas,  677. 

baborenftb,  Coas.,  697. 

balaamea,  lizin.,  697. 

bifida,  Ant,  688. 

bracteata,  Don,  674. 

cephalonica,  £ndl.,  695. 

cilicica,  Kot.,  694. 

concolor,  Engelm.,  681. 

firma.  Ant., 

fraseri,  Pnnb,  684. 

grandU,  Douglas,  678. 

natryana,  nov.  sp.,  689. 

laaiocarpa.  Hooker,  682. 

lowiana,  Oordon,  680. 

nordmanniana,  Stev.,  694. 

pectinata,  Lam.,  693. 

pindrow,  Royle,  690. 

pinsapo,  Boiss.,  697. 

religioBa,  Humb.,  676. 

sibirica,  Turcz,  686. 

yeitchii,  Lind.,  686. 

webbiana,  Wall,  691. 

noy.  ap.  ?  692. 

P  698. 

Acrobolbus,  Iiish  speciea  of,  659. 
Adelanthus,  Irish  species  of,  658. 
Adulteration  detect^  by  fluorescence,  82. 
Alcohol,  new  chemical  test  for,  579. 
AlgtB,  apotheda  in,  85. 
Algebraical  equatbns  of  the  third  degree, 
26. 

R.  I.  A.  PE0C.--V0L.  11.,  8BK.  II.,  8CIBNCB. 


Ammonia,  free  and  albuminoid,  in  watt* r 

of  the  Dublin  streets,  459. 

in  the  lifFey,  461. 

Ammonic       molybdate       used        for 

precipitating  phosphoric  acid,  742. 
Axudysis  of  codls  and  iron  stones  from 

the  Dungannon  Coal  Field,  529. 
Anatomy,  comparatiye,  of  the  lachrymo- 

jugal  suture,  58.  ^ 

of  ligamentum  mucosum,  199. 

Anemometer  cup,  on  the  theory  of,  ami 

the    determination    of  its  constantt:. 

427. 
Anomalies  in  the  course  of  nerves  in 

man,  426. 
Anthelia,  Irish  species  of,  636. 
Anthoceros,  Irish  species  of,  670. 
Apothecia,  occurring  in  alga;,  86. 
Arctic    Regions,    new    fossil    Saurian 

from,  177. 
Arctosaurus  Osbomi,  nov.  gen.  et  sp., 

177. 
Arsenical  compounds,  detection  of,  225. 
Asteralla,  Irish  species  of,  603. 
Astronomical    transit,    observations   on 

personal  errors  in,  484. 

BaUybetagh  Bog,  on  the  exploration  of. 

547. 
,    remains    of  Cervus    megaceros 

found  at,  738. 
Barringtonia  acutangula,  Graertn.,  160. 

3Z 


758 


Index, 


Barringtoma  racemosa,  Roxb.,  160. 

Bpeciosa,  L  ,  160. 

Baizania,  Imh  species  of,  622. 
B^^ryllium,  its  atomic  weight  and  specific 

heat,  731. 
Binocular  form  of  spectroscope,  42. 
Biquadratic,  on  the,  40. 
Bird  myology,  on  some  points  in,  66. 
BIa«ia,  Irish  species  of,  663. 
Blepharostoma,  Irish  species  of,  636. 
Blepharozia,  Irish  species  of,  634. 
Bradypus  giUaris,  cranial  osteology  of, 

139. 
Buoyancy  of  bodies  of  a  greater  density 

than  water,  on  a  cause  of,  22. 

Calamogrostis  epigejoe,  676. 
Calcarina  hispida,  noy.  sp.,  689. 
(Campanula        rotundifblia,        variety 

speciosa,  671- 
Carboniferous  limestones  of  Ireland,  the 

dolomites  of,  706. 
Cave     of    Dunmwe,    animal    remains 

found  in,  480. 

bone  deposits  in,  168. 

Knockninny,  exploratioii  of,  466. 

Cavities,  retro-peritoneal,  79. 
Cephalozia,  Irish  species  of,  624. 
Cervus  megaceros,  remains  at    Bally- 

betaffh,  738,  662. 
Cesia,  Irish  species  of,  669. 
Chemical  changes  in  the  Potato  during 

the  progress  of  the  disease,  736. 
Chemical  Laboratory  of  Trinity  College, 

Dublin,  reports  from,  781. 
Chemical  test,  new,  for  alcohol,  679. 
Chiloscyphus,  Irish  species  of,  630. 
Chlamydomyza   labyrinthuloides,  nov. 

gen.  et  sp.,  140,  169. 
CholoBpus  didactylus,  myology  of,  66. 
Coals  and  iron-stones  from  Dungannon, 

629. 
Conifer®,  structure  of  the  leaves  of, 

209. 
Conocephalus,  Irish  species  of,  601. 
Corona,      m'alformed,     of       Echinus 

eaculentus,  206. 
Cubic  equation,  product  of  the  squares 

of  the  differences  of  the  roots  of,  744. 
Cup  anemometer,  on  the  theory  of,  and 

the  determination  of  its  constants,  427. 
Cyclostigma  kiltorkense,  47. 

Detection    of  arsenical  compounds,  on 

a  ready  means  of,  226. 
Diatomaceee,  Irish,  list  of  {for  index  of 

genera  and  epeeiee,  vide  p.  420),  286. 
Diatoms,  classification  of,  242. 


Diatoms,  distribution  of,  244. 

,  index  of  Irish  species,  420. 

,  motion  of,  237. 

,  reproduction  of,  239. 

,  structure  of,  237. 

Diplophyllum,  Irish  species  of,  642. 
Dissociation  of  molecules  in   solation, 

230. 
District  eight,  of  Ireland,  plants  ne-r 

to,  666. 
Dolomite,  contribution  to  the  hiatnrr 

of,  705. 
Drifting  power  of  tidal  cuirents  rereus 

that  of  wind-waves,  443. 
Dublin  streets,  ammonia  in  the  water  of. 

469. 
Dumortiera,  Irish  species  of.  602. 
Dunmore  cave,  deposits  in,  168. 

Earthquakes  in  Ireland,  9. 

Echinus  esculentus,  malformed,  206, 

Elatine  hexandra,  667. 

Equations,   algebraical,   of    the    third 

degree,  26. 
Equation  of  the  squares  of  the  differences 

of  a  biquadratic,  40. 
Eriocaulon  septangulare,  676. 
Errors,  personal,  in  transit  observation.*, 

484. 
Eugenia  sechellanim.  Baker,  170. 
wrightii,  Baker,  160. 

Flora  of  Aran  compared  with  that  <if 

Bofin,  667. 

of  Inish-Bofin,  Galway,  663. 

Fluorescence,  as  a  means  of  deteeting 

adulteration,  82. 
Foraminifera,  from  Loo  Choo  Islands, 

689. 

from  the  Seychelles,  686. 

Formula)  for  the  solution  of  algebrai<»l 

equations  of  the  third  degree,  26. 
Fossils  from  the  upper  old  red  sandstone 

of  Eiltorcan  Hill,  46. 
Fossombronia,  Irish  species  of,  661. 
Frullania    hutchinsisB,   described     amd 

figured,  608. 
Frullania,  Irish  species  of,  608. 
Fulminic  acid,  newly  observed  propertif*^ 

of  certain  salts  of,  183. 

Geography,  physical,  of  Ireland,  ohang«^ 

in,  6. 
Glucinum,  its  atomic  weight  and  specific 

heat,  731. 
Gonidea  question,  on  the,  92. 
Granite  rocks  of  Tar-Connaught,  102. 
origin  of,  133. 


Index. 


759 


HarpanthnB)  Irish  species  of,  631. 
Heat  as  a  factor  in  vital   action  (so 

called),  1. 
Helianthemuin  guttatum,  566. 
HepaticsB,  Irish,  report  on,  691. 
,  list  of  papers  relating  thereto, 

671. 
Herberta,  Irish  species  of,  635. 
Human  bones  in  Bunmore  Cave,  168, 

173. 
Hygrometer,comparable  self-registeiing, 

further  improvements  of,  166. 

Inish-Bofin,  Oalway,  Flora  of,  653. 
Inks,  on  the  printing,  of  the  sixteenth 

and  seventeenth  centuries,  83. 
Ireland,     changes     in     the     physical 

geography  of,  6. 

,  eailhquakes  in,  9. 

,  eruption  of  lakes  in,  11. 

,  eruption  of  streams  in,  13. 

Irish  Diatomaceae,  list  of,  236. 

Dolomites,  706. 

Hepaticffi,  report  on,  691. 

Ironstones  and  coal  from  Bungannon, 

629. 
Isoetes  echinospora,  577. 

Jungermannia,  Irish  species  of,  646. 

Kallispongia  archerii  nov.  gen.  et  sp., 

766. 
Rantia,  Irish  species  of,  632. 
Kiltorcan  Hill  fossils,  46. 
Knockninny  cave,  on  the  exploration  of, 

465. 
account  of  animal  remains  found 

in,  480. 

Laboratory  notes,  81. 

Labyrinthula  macrocystis,  Cienk,  163. 

vitellina,  Cienk,  161. 

Lachrymo-jugal   suture   in   a    human 

skuU,  68. 

comparative  anatomy  of,  60. 

Lagrange's    equations    of    motion    in 

generalized     co-ordinates,     on     an 

elementary  proof  of,  463, 
Laurencia     paniculata,     Foraminifera 

parasitic  on,  589. 
Leaves  of  Conifers,  structure  of,  209. 
Lejeunea,  Irish  species  of,  610. 
flava,  Swartz,  found  in  Eillamey, 

672. 
moorei,  lind.,  described  and  figured, 

616. 
' patens,    Lind.,     described    and 

figured,  615. 


Lepidozia,  Irish  species  of,  621. 
Liffey    river,    free    and     albuminoid 

ammonia  in,  469. 
Ligamentum  mucosum,  198. 

comparative  anatomy  of,  199. 

Ligamentum  pterygo-spinosum,  202. 
Lime,  phosphate  of,  in  stalagmite,  176. 
Lisdoonvama,  mineral  waters  of,  189. 
Loo  Choo  Islands,  foraminifera  from,  589 . 
Lophocolea,  Irish  species  of,  628. 
Lunularia,  Irish  species  of,  604. 

Man,  nerves  in,  anomalies  in  the  course 

of,  426. 
Marchantia,  Irish  species  of,  600. 
Martes  foina,  myology  of,  48. 
Mastigophora,  Irish  species  of,  684. 
Mercury,  fulxninate  of,  183. 
Metzgeriea,  Irish  species  of,  666.  ^ 

Microscopical  structure   of   rocks,  94, 

161,  164. 
Mineral  waters  of  lisdoonvama,  189. 
Molecules  in  solution,  on  the  dissociation 

of,  230. 
Muscles  of  Cholospus  didactylus,  table 

of  weights  of,  78. 
Mylia,  Irish  species  of,  645. 
Myology  of  Choloepus  didactylus,  66. 

BiVds,66. 

Martes  foina,  48. 

Nasua  fusca,  48. 

narica,  48. 

Myrtacesd,  from  Seychelles,  160. 

Nardia,  Irish  species  of,  654. 
Nasua  fusca,  myology  of,  48. 

narica, ,  48. 

Kerves  in  man,  anomalies  in  the  course 
of,  426. 

Odontoschisma,  Irish  species  of,  623. 
Osteology,  cranial,  of  Bradypus  gularis, 
139. 

Palffiopteris  Hibemica,  46. 
Pallavicinia,  Irish  species  of,  661. 
Pandarina,  on  a  new  genus  of,  583. 
Pedinophyllum,  Irish  species  of,  629. 
Pellia,  Insh  species  of,  664. 
Pentastoma  aonycis,  nov.  sp.,  66. 

imperatoris,  nov.  sp.,  62. 

Peretyphlic  pouches,  214. 

Personal  errors  in  transit  observations. 

484. 
Petaloph;j^llum,  Irish  species  of,  663. 
Phosphoric      acid      precipitated      by 

ammonic  molybdate,  742. 
Plagiochila,  Irish  species  of,  643. 


760 


Index. 


Pleurozia,  Irith  ipecies  of,  619. 
PoUruation  of  the  lodiacal  light,  218. 
Polydactylinn,  on  a  caae  of,  639. 
Porella,  IriBh  species  of,  617. 
Potato  disease,  chemical  changes  during 

the  progress  of,  736. 
Preissa,  Irish  species  of,  602. 
Printing    inks    of   the    sixteenth    and 

seventeenth  centuries,  on  the,  83. 
Product  of  the  squares  of  the  diffetences 

of  the  roots  of  a  cubic  equation,  744. 
Pseudotsuga  douglaaii.  Sab.,  703. 

fortunei,  Pari.,  702. 

magniflca,  A.  Mur.,  700. 

nobilis,  Doug.,  699. 

Quadratic  expression,  (2*  -  3PP',  744. 
Quinqueloculina  omatissima,  690. 

Radula,  Irish  species  of,  616. 
Rptro-peritoneal  cavities,  new  form  of, 

79. 
Rhinodon  tv^icus,  683. 
Riccardia,  Irish  species  of,  667. 
Ricoia,  Ixish  species  of,  606. 
Ricciella,  Irish  species  of,  606. 
Ricciocarpus,  Irish  species  of,  607. 
Rooks,  ingenite,  structute  of,  94,  180. 
of  Xar-Connaught,  &c.,  102,  174. 

Saccogyna,  Irish  species  of,  632. 

Sagenaria  bailyana,  46. 

Salts  of  fulminic  acid,  newly  observed 

properties  of,  183. 
Sarcodic  organism,  on  a  new  freshwater, 

140. 
Saurian,  new  fossil,  from  Arctic  Regions, 

177. 
Scalia,  Irish  species  of,  660. 
Scapania,  Irish  species  of,  637. 


Seychelles  Myrtacese,  160. 

,  a  new  genus  oiF  Pandarisa  frtix. 

683. 
^^,  Foraminifera  from,  686. 
Sirosiphon,  apothecia  in,  89. 
Skull,  human,  lachrymo-jugal   satun 

in,  68. 
Solution  of  alloys  and  metals  by  aci(l>. 

on  the,  81. 
Spectra,  faint,  on  a  spectroscope  for  thf 

observation  of,  42. 
Spectroscope  of  the  binocnlar  fonn.oo 

a,  42. 
Spectrum,  ftc,  of  the  zodiacal  light.2l$. 
SphsBTOcarpus,  Irish  species  of,  669. 
SpirotsBnia  graciHima,  nov.  sp.,  148. 
Sponge,  on  a  new  genus  and  specie?  of. 

766. 
Stasiotes    rhinodontts,    nov.    gen.    ft 

spec.,  684. 
Stigonema,  apothecia  in,  90. 
Syctonema,  apothecia  in,  88. 

Targionia,  Irish  species  of,  606. 
Tetrapteryx  stanleyannus,  lumbar  and 

sacral  plexus  of,  67. 
Tidal  currents,  the  drifting  power  of. 

ver$u»  that  of  wind-waves,  448. 
Transit  observations,  on  personal  erron: 

in,  484. 
Trichocolea,  Irish  species  of,  633. 
Tsuga,  species  of,  211. 

Vital  action,  on  heat  as  a  factor  in,  1. 

Waters,  mineral,  of  lisdoonvama.  189. 
Wind-waves  and  tidal  currents,  443. 

Zodiacal  light,  its  speotrum,  &c.,  218. 


N.B.— Date  of  publication  of  the   several  Parts  of  Volume  II., 

Serie« 

Science : — 

Part  1,   pp.     1  to    84,  January,  1876. 

„    2,     „    86  „  176,  April, 

„    3,     „  177  „  234,  July, 

„    4,    „  236  „  424,  October,       „ 

„    5,     „  426  „  468,  January,  1876. 

„    6,     „  469,,  690,  July, 

„    7,     „  691  „  766,  January,  1877. 

END  OP  VOLUME  II. 


PROCEEDINGS 


OF  THE 


ROYAL   IRISH  ACADEMY. 

VOL.  II.,  SERIES  2. 


SCIENCE. 


DESCRIPTION  OF  PLATES. 


PLATE  1. 

Illxtstaatiye  of  Pbofessos  Macalxstes's  Papeb  on  *'  The  Pbbsencb 
OF  a  Lachbtxo-jugal   Sutube  if  a  HnicAN    Sbull,  and  on  its 

GoMPAKATITB  AnATOICT." 

Fide  Piroceedings  R  I.  Acad.,  VoL  2,  Ser.  2,  p.  68. 

Fig.  I.  Human  ekull. 

Mx.    Maxillary  bone. 

Mx.«  Superior  maxillary. 

L.       Lachrymal  bone. 

E.       Ethmoid. 

J.        Jugal  Bone. 
Fig.  2.  Ehesus. 

Mc«  Maxillary  bone. 

L.     Lachrymal  bone. 

Fr.    Frontal  bone. 

J.      Jugal  bone. 

P.     Parietal. 

8.     Squamous  portion  of  Temporal. 

Z.      Zygomatic  process  of  TemporaL 

I.     Supra-orbital  foramen. 


PLATE  2. 
Illvbtritite  or  Profxssob  Macalutkb's  Paper  "Ok  two  vrw  Spectes 

OF  PSVTASTOXA." 

Fide  Proceedings  E.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  62. 

Fig.  1.  Pentastoma  imperatoris,  sp.  nov.  female,  nat.  dze. 

2.  „  „  male,  x  4 — a.  mouth ;  h.  intestiiie. 

3.  „  „         female  head — a.  papillae;    b.  donal 

wart. 

4.  ,j  f,  „      claw,  X  50,  showing  retractor 

and  depressor  muscles. 

5.  „  „  „      reproductive  oi^ans—a.  coiled 

oviduct;  b.  receptacula  seminis; 
e,  ovarian  ducts;  d,  ovary;  e,  uterus. 

6.  ,,  „  male  reproductive    organs  x    18— 

a.  oesophagus;  b,  accessory  sacs  con- 
taining chitinous  processes ;  (.  cir- 
rhus  ;  d,  sac  of  ditto ;  e.  accessory 
gland ;  /.  point  where  the  vas  de- 
ferens ends  in  the  cirrhus ;  y.  end 
of  cirrhus. 

7.  9,  „  striped  muscle  from  retractor  of  claw 

x350. 

8.  „  „  vertical   section   of  part    of  body 

wall;  a.  chitinous  epidermis;  b,  hy- 
podermis;  e.  longitudinal  muscle; 
d.  circular  ditto  ;  e.  lining  mem- 
brane ;  /.  body  cavity ;  y.  wall  of 
oviduct;  A.  ova. 

9.  „  rf  section  of  intestine  X  16,  partly  dia- 

grammatic 

10.  „  r,         portion  of  oviduct  above  uterus. 

11.  Pentastoma  aanycis,  sp.  nov.  female  x  6. 

12.  „  „        mouth. 

13.  ,,  „        claw  X  50. 


PLATE  3. 

Illtjstbatitx  of  PbopbssosMacalistes's  Fapeb  ''  Ok  two  kkw  Sfscdm 
OP  Pbntistoma." 

Fide  Proceedinga  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  62. 

Figs.  1  to  18.  Pentastoma  imperatoriB^  sp.  nor.  representing  different 

stages  of  Ova  and  Embryos. 
Pig.  14.  Pmta%toma  HKmycis,  sp.  nov.,  portion  of  skin  of,  x  100. 


PLATE  4. 

ILLT78TRATITE  OF  Mb.  W.  H.  MaCXTNTOSH's  PaPIS   "  On  TKE  MuSCUIAK 
AVATOMT  OF  GhOLCBPUS  DiDACTTLVS." 

Fide  Proceedings  B.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  66. 

Cholofpus  didaetyluB^  muscles  of  hind  limb, 

a.  PanniculuB. 

h.  External  oblique. 

e,  Iliacus. 

d,  Sartorins  femoralis. 

e.  Adductor  magnus  (the  rectus  is  seen  just  above). 
/.  Bifid  gracilis. 

y.  Biceps  femoris. 

A.  Flexor  hallucis  and  flexor  longua. 

I.  Two  tendons  of  gastrocnemius  extemus. 


PLATE  5. 

Illustrative  of  Mb.  G.  R.  Leeper's  Paper  on  "  Rbtro-pebitoheal 
Cavities  iw  Man." 

Fids  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  79. 

Fig.  1.  Recesstts  Ileo-coecalis. 

2.  Fossa  subcoecalis. 

3.  Fossa  retro-coBcalis. 

C.  Coecum.  I.  Ileum.  I.  c.  Ileo-colic  Artery.  K.  Knife  passed 
through  the  long  mesocoecum.  Mo.  Mesocoecum.  Mm.  Mesenteriolum. 
My.  Mesentery.  P.  i.  c.  Plica  lleo-coecalis.  P.  m.  Cut  edge  of  the 
Peritoneum.  Ps.  Psoas  magnus.  Ps'.  Psoas  parvus  tendon.  F.  s.  c. 
Fossa  subcoecalis.  .  Fi.  Fascia  iliaca.  R.  Fossa  retro-coecalis.  R.  i.  c. 
Recessus  ileo-coecalis.  T  e.  Tcenia  externa.  V.  a.  Vermiform  ap- 
pendix. 


PLATE  6. 
Illustrative  of  Mb.  Abchek's  Fafeb  "  On  Apothecia  in  some  Sctto- 

N£MACE£  AND  SiBOSIPHONACEiB.'' 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  85. 

i'ig.  1 .  Ascus  witli  4  spores. 

2.  Single  spore  x  403. 

From  an  unidentified  SeyUmema, 

3,  4,  5.  Apothecia. 

6.  Mature  apothecium. 

7.  Same  (in  outline)  burst,  to  show  protruding  asci  and  para- 

physes. 

8.  Spore  x  400. 

^11.  Showing  internal  agglomeration  of  brownish-coloured  gra- 
nules causing  swellings  of  the  filaments  (incipient  apo- 
thecia ?) 

From  SiroHphon  alpinus, 

12.  Fully  formed  apothecium. 

13.  Younger  apothecium. 

14.  Spore  x  400. 

15.  Ascus,   immature,   with  paraphyses,   showing  contents  con- 

tracted into  a  fusiform  figure  and  divided  transversely. 

16.  17.  Immature  asci  with  paraphyses. 

18.  Showing  portion  of  an  apothecium  burst  so  as  to  cause  the 

8-spored  asci,  with  paraphyses,  to  become  extruded  (the 
rent  portion  of  the  apothecium  not  shaded). 

From  Siroaiphan  pulvinatiM  or  S.  Heufleri. 

19.  Immature  apothecium. 

20.  Outline  of  mature  apothecium. 

21.  Immature  asci. 

22.  Mature  ascus  with  8  spores. 

23.  Spore  x  400. 

From  Stiff onema  mamillosum, 

24.  Apothecium. 

25.  Immature  asci  with  paraphyses. 

26.  Spore  x  400. 

tt.  I.  A.  PHOC,  8BR.  II.,  VOL.  11.,  SCIENCE.  b 


PIATE  7. 

IixvsTBATiys  OP  Mb.  Kdtahak's  Paper  **  On  MiCBOscopicix  SrBrcTuitK 

OP  Rocks." 

Vide  Proceedings  R.  I.  Acad.,  Yol.  2,  Ser.  2,  p.  94. 

Fig.  1.  Orthoclase  (F.  Butly),  Yetterly,  Sweden  (42  diam.) 

2.  Junctions  of  twin  crystals  of  flesh-colonred  felspar  (Enocka- 

navaddy),  Co.  Galway  (42  diam.) 
8.  Crystals  of  amphibole  and  mica  in  tlie  flesh-colonred  felspar 

(42  diam.) 

4.  Inlying  crystalline  moss  in  the  flesh-colonred  felspar  (42  diam.) 

5.  Crystals  of  magnetite  (?)  and  pyrite  in  the  flesh-colonred  fel- 

spar (296  diam.) 

6.  A  portion  of  one  of  the  small  crystals  of  the  flesh-colonred 

felspar  (42  diam.) 

7.  A  portion  of  a  mass  of  the  dull  white  felspar  (adnlaria  ?)  from 

the  Enockanavaddy  granite,  showing  contained  portions  of 
a  triclinic  felspar  (oligoclase  ?)  that  have  a  ribanded  stmc- 
ture  42  diam.) 

8.  A  crystalline  mass  of  adnlaria  (?)  in  which  there  is  an  incipient 

or  faint  lining  (42  diam.) 

9.  A  portion  of  a  crystal  of  oligoclase  (F.  Rutly)  Yetterly,  Swe- 

den, showing  its  stmctnre  (42  diam.) 

10.  Portions  of  crystals  of  triclinic  felspar  (oligoclase)  from  the 

Knockanavaddy  granite  (42  diain.),  {aa)  irregolar  flakes  of 
mica,  {I)  small  crystals  of  titanite,  {c)  roundish  piece  of 
flesh-coloured  orthoclase. 

11.  Part  of  a  large  crystal  of  titanite  with  which  are  two  small 

crystals  of  the  same  mineral,  one  an  inlier  (42  diam.) 

12.  Dull  white  felspar  crystals  (adnlaria) — Furbogh,  (xalway — 

showing  peculiar  structure  (238  diam.) 


PIATE  8. 

Illustkatiye  of  Mb.  Einah ait's  Paper  "  On  Micboscopical  Stbuctlbk 

OP  Rocks." 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  94. 

Fig.  13.  A  portion  of  the  lower  right-hand  crystal  in  Fig.  13,  PI.  7, 
enlarged  386  diameters. 

14.  Inlying  minerals  in  the  triclinic  felspar  Furbogh  granite 

(238  diam.) 

15.  Peculiar  structure  of  the  triclinic  felspar,  196  diameters. 

16.  Part  of  Fig.  15,  marked  (&),  enlarged  386  diameters. 

1 7.  Peculiar  structure  of  the  triclinic  felspar,  296  diameters. 

18.  Blebs  of  quartz  in  the  Kilkullen  granite  (42  diam.),  right- 

hand  a  crystal,  left  hand,  the  quartz  having  a  pellicle. 

19.  Blebs  of  quartz  in  Elvanyte,  from  near  Ghdway  (42  diam.), 

right  hand,  a  crystal,  left-hand,  irregular  secretion  with  a 
pellicle. 

20.  Part  of  Fig.  18,  marked  (a),  magnified  196  diameters. 

21.  Part  of  Fig.  20,  marked  (a),  magnified  386  diameters. 

22.  Part  of  Fig.  18,  marked  {b),  magnified  296  diameters.    In  the 

lower  right-hand  portion  of  the  figure  are  five  tubes  from 
the  feather-shaped  arrangement  a  little  to  the  left,  which 
are  magnified  386  diameters. 

23.  A  portion  of  the  centre  of  the  right-hand  crystal  in  Fig.  19, 

magnified  about  350  diameters,  to  show  the  tubidi  or  short 
gas  tubes.  The  two  pointed  cones  below  the  tubes  are 
oblique  sections  of  tubes. 

24.  A  portion  of  some  of  the  quartz  of  the  Furbogh  granite,  mag- 

nified 240  diameters,  showing  eapillouhf  or  hair-like  lines 
and  regular  systems  of  tubuli.  In  the  upper  left-hand 
portion  of  the  figure  is  an  inlying  crystal. 


PLATE  9. 

Illuktrativk  of  Mr.  Kinahan's  Paper    **  Oy   Granitic    axd  othh 
IiroENiTE  Bocks." 

Fid0  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  102, 

A.  DiagFommatic  sketch  of  a  doleryte  dyke,  seemmg  oae  rock,  but  ol 

different  textures  in  different  parts — a  and  h,  clay  or  shale 
partings ;  e  and  d  caught  up  pieces  of  schist.  In  the  Yidnity 
of  the  parting  h,  the  rock  is  amygdaloidal,  while  the  diTisias 
of  the  dyke  on  the  left  of  that  parting  has  a  rade  horizontal 
columnar  structure  combined  in  places  with  a  fitpheroidal 
structure.  The  arm  to  the  left  has  a  rude  columnar  stractnre.— 
aeggan. 

B.  Diagrammatic  sketch  of  a  doloryte  dyke  in  felsite-schisty  showing 

a  platy  and  spheroidal  structure. — ^Mannio  Bay. 

C.  Sketch-map  of  part  of  a  dyke  of  felstone  in  granite.     In  the  whole 

of  the  felstone  is  a  structure  oblique  to  the  walls  of  the  dyke, 
while  in  part  are  lines  nearly  perpendicular  to   the  others, 
giving  the  rock  a  tesselated  aspect. — ^Lough  Bola. 
B.  Nodular  or  conglomeritic-gneiss,  changing  into  granitoid-gneiss.^ 
Berrycemlagh. 

E.  Angular  pieces  of  schistoid-granite  in  intrusive  oligodasic-graxute.— 

Omey  Island. 

F.  Section  of  conglomiretic-schist. — ^Ardadeny. 

G.  Sketch-map  of  a  small  rock  exposure,  showing  scaled  old  joint- 

lines  in  a  homblende-aphanyte. — ^Letterdife. 

H.  Sketch-map  of  a  small  rock  exposure,  showing  some  of  the  old 
joint-lines  scaled,  while  others  are  still  open,  but  a  small  thick- 
ness of  rock  alongside  is  indurated,  and  when  the  rock  is 
weathered  stands  up  in  a  ridge. — Glan. 

1.  Sketch-map  of  a  small  exposure  of  micacoous-homblende-rock, 
showing  the  pitted  surface  caused  by  the  weathering  out  of  the 
small  bunches  of  mica  plates. — Knockadai. 

J.  Sketch-map  of  a  weathered  suiiace  of  a  micaceous-homblende-rock 
containing  largo  flakes  of  silvery-white  mica,  the  weathered 
edges  of  the  latter  having  a  peculiar  angular  arrangement.— 
Mannin  Bav. 


PLATE  10. 

Illustratiye  of  Mb.  Kutahan's  Pafes   **Oix  Obakitio  and  other 
iKOEiaTE  Bocks." 

Fide  Proceedings  B.  I.  Acad.,  Vol.  2,  8er.  2,  p.  102. 

£.  Sketch  of  a  bomboid  protxasion  of  homblende-aphanyte  in  a  mass 
of  steatyte. — ^Inish  Boiin. 

L.  Diagrammatic  sketch  of  a  section  showing  homblende-rock  asso- 
ciated with  hornblende-schist,  the  latter  alternating  upwards 
with  mica^schist ;  {a)  mica-schist ;  (&)  Hornblende-schist  ; 
(c)  homblende-rock. — ^Denycnnlagh. 

M.  Nodular  homblende-rock  passing  upwards  into  conglomeritic- 
gneisB. — ^Derrycunlagh, 

N.  Nodular  homblende-rock  passing  at  the  edge  of  the  flow  or  bed 
into  conglomeiitic-gneiss. — ^Derrycunlagh. 

0.  Veins  of  segregation  of  three  ages  in  orthoclasic-granite ;  (a)  new 
open  joints;  (h)  newest  veins;  {e)  second  veins;  {d^  oldest 
veins. — Cashla  Bay. 

P.  Sketch-map  of  a  rock-surface  of  hornblende-schist  showing  the  old 
joint-lines  forming  hard  lines,  and  the  associated  rock  indu- 
rated.— ^Ardadeny. 


PIATE  11. 

iLLuerTiUTiTB  OP  Mb.  Kiitahav's  Fapeb   "On  O&anitic  jjtd   otB£r 
IiroisNiTE  Bocks." 

Fide  Proceedings  R.  I.  Acad.,  Yol.  2,  Ser.  2,  p.  102. 

Fig.  Q.  Map  of  Cashel  Hill,  showing  the  exotic  rocks  associated  with 
tufp,  while  both  are  distinct  from  the  rocks  of  the  sorroimd- 
ing  country. 


PLATE  12. 

Illvstbatiyb  of  Mb.  Kivahak's  Paper   **  Oh  Gbakitic  A9D  oihsb 

LrOEZOTE  E0CX8." 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  102. 

Fig.  E.  Vertical  section  across  the  summit  of  Cashel  Hill. 

Fig.  S.  Section  across  Knocksofin,  showing  the  graduation  of  the  oli- 
goclasic  granite  through  gneiss  into  schists,  and  their  rela- 
tions to  somo  of  the  exotic  rocks. 


PLATE  13. 


iLLrsTKATITX    OP    PsOPESMK    HACALNTBR'a    FaPEK   "  Ov   THK    CwULWlAl. 

OsnoLooT  OF  SuncHs." 


Fig.  1. 


Fig.  2. 


Fig.  3, 


Fig.  4. 


BradypUB  guUru,  Skull,  nat.  size. 

Parietal. 

8npra-occipital. 

SqnaxnofiaL 

Exoccipital. 

Condyle. 

Ditto, 

f  nat.  size. 

Lacbrymal  bone. 

Nasal  bone. 

Frontal  bone. 

ParietaL 

Squamosal. 

/ 

Supra-occipital. 

9 

Occipital  crest. 

h 

Exoccipital  bone. 

% 

Condyloid  foramen. 

J 

Bulla  tympani. 

k 

Pterygoid. 

I 

Foramen  ovale. 

m 

Zygomatic  process  of  squamosal. 

n 

Jugal  bone. 

0 

MaxiUa. 

p 

Premaxilla. 

I  Fontanelle  bones,  nat  wze. 

a 

Wormian  bones. 

h 

Left  parietal  bone. 

e 

Right  parietal  bone. 

d  Si  e  Wormian  bones. 

/ 

Supra-occipital  left. 

P 

Meso-occipital  suture. 

h 

Supra-occipital  right. 

Fronto-lachrymal  region  x  4. 

a 

Jugal. 

h 

Lachrymal. 

e 

Frontal. 

d 

>f  axilla. 

e 

Lachrymal  foramen. 

f 

Infra-orbital  foramen. 

Fig.  5.  X  12,  Stapes. 


PIATE  14. 
Illustbative  of  Mr.  Abhiher's  Pafeb  "  Oir  Chlamtdomtxa  labtbin- 

THULOIBES,  K.  G.  ET  SP." 

Vtde  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  140. 

Plate  14  represents  an  entire  example,  the  body-mass  having  be* 
come  extruded  through  the  torn-like  opening  in  the  many-layered 
outer  envelope,  and  showing  the  greenish,  reddish,  and  blueish-colour- 
ing  granules,  pulsating  vacuoles,  and  some  incepted  foreign  bodies. 
For  extending  in  a  tortuous  reticulated  ^'labyrinth"  are  seen  the 
filamentary  tracks  (Eadenbahn,  Gienkowski)  with  numbers  of  the  blueish 
granules  travelling  thereon,  now  becoming  fusiform  in  figure  {Spin- 
dies).  Towards  the  left  of  the  example,  in  an  outlying  portion  of  the 
mass  is  seen  a  vacuole  showing  a  temporary  cleft  or  rift  in  the  sub- 
stance at  each  side  of  it.  Towards  the  right  is  seen  a  nearly  isolated 
colony  of  the  mass  containing  a  digested  example  of  Ooeystis  Naegelii, 
At  the  further  extremity  occur  two  similar  nearly  isolated  portions, 
one  showing  imbedded  an  as  yet  undigested  example  of  Spirotania 
graeUlima  (n.  s.),  all  these  outlying  portions  showing  some  vacuoles. 
Towards  jbhe  left  of  the  figure  a  small  portion  of  the  body-mass  has 
become  on  some  former  occasion  independently  re-encysted,  and  is  now 
♦*  dormant."  x  400  diam, 


B.  I.  A.  PBGC.,  8BB.  U.,  TOL.  tl.,  8CIBNCE. 


PIATE  15. 

iLLUflTEAHTS  OP  Me.  AsCHXs'b  PaFKE   "  Ov  CHLA]fTIX)inrXA   LABTRHr- 
THULOIDSS,  K.  O.  BT  8P." 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  140. 

Fig.  1  shows  certain  bodies  band  in  the  cells  of  a  Sphagnam 
occuning  in  the  same  pool  [and  often  on  the  same  plants,  which  har- 
bour undoubted  examples  of  this  organism  (4b  shown  in  next  figure),] 
and  which  are  supposed  to  have  some  genetie  reU&tionflhip. 

Fig.  2. — A  portion  of  a  leaf  of  Sphagnum  showing  yoting  Ckiam^- 
domyxa  examples ;  to  the  left  are  seen  green  6ned,  near  the  bottom  two 
very  small,  still  globular,  towards  the  middle  a  few  now  red,  owing  to 
the  abundance  of  the  red  granules ;  the  lUrg^  examples  have  put  <a  a 
torulose  figure,  owing  to  the  constriction  caused  by  the  recuning  cine- 
ture  of  the  annular  fibre  of  the  Sphagnum-cell.  Towards  tiie  right  i» 
seen  a  CMamydtmyxa  extruded,  and  still  attached  by  a  neck*like  por- 
tion of  the  wall ;  the  contents  have  become  re-encysted  now  outside 
the  Sphagnum-cell. 

Fig.  3. — A  condition  rarely  met  with,  showing  the  inner  sarcodic 
substance  subdivided  in  a  number  of  nearly  equal-sized  globular  }>or- 
tions,  the  sub-contents  reddish  inclining  to  orange,  and  eaoh  indivi* 
dual  ball  encysted  in  its  proper  wall ;  the  whole  Within  the  oiater 
many-layered  original  envelope. 

Fig.  4. — ^The  many-layered  envelope  of  an  example  after  severe 
pressure,  the  most  of  the  substance  removed,  a  few  colouring  granules 
only  being  left. 

Fig.  5. — ^A  small  example  after  being  boiled  in  caustic  potash. 

Fig.  6. — ^Portion  of  an  example  treated  with  iodine  and  sulphuric 
acid. 

All  the  figs.  X  200  diams. 


PLATES  16  &  17. 

Illustjuitivb  op  Mb.  Bakeb's^  Papsr  "On  the  Mtbtace^s  of  the 
Seychelles." 

Fide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  160. 

Plate  16. — Eugenia  Wrightii. 
Plate  17. — Eugenia  Sechellaruni. 


PLATE  18. 
Illustrative  of  Mr  Hardmak's  Paper  **  On  the  Gate  of  DrsnroRE, 

Co.  KlLKEWNT." 

Fide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  168. 

Fig.  1.  Plan  of  Cave. 

2.  The  market  cross  stalactitic  pillar. 

3.  Section  at  end  of  rabbit  borrow.     Fide  p.  170. 

4.  Recess  near  market  cross. 

5.  Fairies'  floor. 


PLATES  19  AND  20. 

Illusteatiyx  op  Mb.  Macaxisxeb's  Papeb  *^  Ox  some  fobms  of  thb 

LlOAJEEXTUM  PtEBYGO-BPINOSUIC." 

Vide  Proceedings  R.  I.  Acad.,  Yol.  2,  Ser.  2,  p.  110. 

[^In  aU  the  Figures  the  letters  have  the  same  significance,'] 

E.  External  pterygoid  plate. 

I.   Internal  pterygoid  plate. 

A.  Accessory  external  pterygoid  plate  (Fig.  12). 

0.    Spina  accessoria  (in  Fig.  14  a  =  ligamentum  pterygo-spinosum 

accessorium). 
/.    Lower  spine  on  the  external  pterygoid  plate. 
f».  Muscular  ridge  on  the  external  pterygoid  plate, 
mm.  Middle  meningeal  artery. 

n.    Notch  between  the  two  teeeh  on  the  external  pterygoid  plate. 
0.    Foramen  ovale,     o'.  Inner  accessory  opening  thereinto. 
p.   Spina  angularis. 

r.    Bidge  of  thickened  ossified  ligament. 
9,    Foramen  spinosum. 

t.    Inner  accessory  aperture  into  foramen  spinosum. 
u.  Upper  tooth  on  the  external  pterygoid  plate. 
X,   Suture  on  the  ossified  ligament. 


PLATE  19. 


Fig.  K  Outer  view  of  outer  pterygoid  plate,  adult  male,  showing  a 
muscular  ridge,  and  well  marked,  but  separate  spinee  angu- 
laris and  accessoria. 

2.  Outer  side  of  right  outer  pterygoid  plate,  showing  two  hinder 

teeth,  as  well  as  spinsB  angularis  and  accessoria. 

3.  Inne^  side  of  right  outer  pterygoid  plate,  showing  a  large  per- 

foration (/)  co-existing  with  a  notch. 

4.  Outer  view  of  right  outer  pterygoid  plate,  showing  a  deep 

notch. 

5.  Inner  side  of  right  pterygoid  plates,  showing  lower  and  upper 

teeth. 

B.  L  A.  PEOC,  8EB.  IL,  VOL.  II.,  BOIBNCB.  d 


6.  Inner  side  of  left  pterygoid  plates,  showing  a  large  projecting 
lower  muscular  tooth  on  the  external  pterygoid. 
Fig.  7.  Outer  side  of  right  external  pterygoid,  showing  spina  acces- 
soria  co-existing  with  a  bridge  across  the  foramen  spino- 
sum  (a'). 
8.  Ossified  ligaments  forming  a  thick  prominent  ridge,  on  the 
outer  and  inner  side  of  which  are  inlets  into  the  oval  and 
spinal  foramina,  which  in  vertical  section  are  Y-shaped. 


PLATE  20. 

9.  Ossified  ligamentum  pterygo-spinosum,  showing  a  suture  in 
the  ossified  bridge,  co-existing  with  a  spina  accessoria. 

10.  Ossified  ligamentum  pterygo-spinosum  accessorium,   with    a 

suture  in  the  bridge  of  bone. 

11.  Ossified  ligamentum  pterygo-spinosum  accessorium,  bridging 

over,  and  dividing  the  inlet  into  the  foramen  ovale  into  two 
parts,  spina  angularis  free,  a  back-directed  spine  from  the 
spina  accessoria  overlapping  the  foramen  spinosum. 

12.  Pterygoid  processes  from  Chatham  Island  skull,  showing  the 

accessory  outer  pterygoid  plate. 

13.  Ossified  ligamentum  accessorium  pterygo-spinosum,  with   no 

suture. 

14.  ligamenta  pterygo-spinosum  {p.s.)  et  accessorium  («),  show- 

ing their  relation  to  the  middle  meningeal  artery  (m.  m.), 
and  to  the  temporal  nerves  (^,  ^'). 

15.  Ligaments  in  another  specimen,  showing  their  fusion  at  their 

pterygoid  end. 


PLATES  21  AND  22. 
iLLusniATiyx  OP  Me.  Maoktstosk^b  Paper  "  Oir  a  Malfosksd  Cobona 

OF  EuJLLNUS  SSCULEiniTB." 

Vide  PpoceedingB  B.  I.  Acad.,  Tol.  2,  Ser.  2,  p.  114. 

Flats21. — Tig,  1.  Abactinal  aspect  of  corona.  I.,IL,m.,rV'.,V., 
genital  plates.  1,2,3, 4,  5,  ocular  plates.  Plate  I.  is  the  madreporic  ; 
plate  II.  is  seen  to  have  lost  its  genital  pore,  a,  right  prong  of  ambula- 
cram  2,  stopping  short  a  little  above  the  ambitus.  (In  this  ambulacrom, 
in  this  and  the  next  figure,  the  lithographer  has  in  many  instances 
represented  as  dots  what  are  really  small  tubercles,  and  thus  the  pores 
seem  much  more  numerous  than  they  actually  are),  a',  a  group  of 
three  or  four  pores  belonging  to  ambulacrum  a.  cl\  pores  belonging 
to  the  left  prong  of  ambulacrum  a,  which  are  placed  inside  the  inter- 
ambulacral  plates  of  Ila.  /i,  large  central  plate  round  which  a  number 
of  other  plates  are  arranged  in  a  radiate  manner.  «,  a  small  peif  ora- 
tion through  the  corona,  apparently  a  hole  produced  by  absorption. 

Fig.  2.  Corona  seen  from  left-hand  side,  a,  a',  as  before ;  5,  actinal 
boss.  The  point  of  bifurcation  of  ambulacrum  2  is  seen  near  the 
bottom  of  the  figure ;  also  the  remarkable  ''  petaloid"  appearance  <^ 
interambulacrum  II.,  and  the  scattered  arrangement  of  the  pores  in  the 
left  prong  of  ambulacrum  2. 

Plate  22. — Fig.  3.  Posterior  aspect  of  corona,  showing  the  remark- 
able alterations  which  the  plates  have  undergone.  Beferences  as 
before. 

Fig.  4.  Actinal  aspect  of  corona,  n,  h^  as  before ;  the  line  h  termi- 
nates on  the  summit  of  the  boss.  Ambulacrum  1  is  seen  to  have  a 
very  short  course,  terminating  a  short  distance  beyond  the  top  of  the 
boss.  The  bifurcation  of  ambulacrum  2«  is  seen  to  take  place  about 
half  way  between  the  margin  and  the  edge  of  the  actinal  orifice,  the 
whole  of  which  is  displaced  downwards  and  to  the  right-hand  side. 
The  sutures  of  the  plates  in  the  neighbourhood  of  the  altered  parts  are 
almost  entirely  obliterated. 

All  the  figures  are  reduced  to  about  %  the  natural  size. 


PIATE  23. 

iLLusnuxiTB  OF  Mb.  M'Nab'b  Fapeb,  **  Rekasks  on  ths  Sxsuctuhs  or 
THE  Lbatxs  of  csrtaik  Cokiferjs." 

Fids  Proceedings  B.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  209. 

Fig.  1.  Finns  Hookeriana. 

2.  Finns  Fattoniana. 

3.  Finns  canadensis. 

4.  Finns  Mertcnsiana. 

5.  Finns  Bmnoniana. 

6.  Finns  Sieboldii. 

All  the  Figures  are  magnified  20  diameters. 

e.  Epidermis. 

A.  Hjpoderma. 

e.  Besin  canal. 

#.  Sheath  of  the  Fibro-vascnlar  bnndles. 

I  The  letteri  refer  to  all  the  Figures.] 


PLATE  24. 

Illustb^titx  of  Mr.  Macalisteb's  Papsr  '<  Ov  Two  Dissdolab  f  oems 
OF  Pekittphlic  Pouches." 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  8er.  2,  p.  214. 

Fig.  L  Fossa  Ectrocsecalis. 

a.  Abdominal  wall,  cut  and  reflected. 

b.  External  cutaneous  nerve. 

c.  Ilio-inguinal  nerve. 

d.  Fossa.' 

0,  Crest  of  ilium. 

/.  Ascending  colon,  torn  out  of  its  bed. 

^.  Ureter. 

h.  Hiac  artery. 

t.  Genito-crural  nerve. 

J.  Psoas. 

Fig.  2.  Subc8Bcal  Fossa. 

a.  Abdominal  wall,  cut  and  reflected. 

b.  Ligamentum  c»ci  (Huschke). 

c.  Ascending  colon. 

d.  Fossa  ileo-C8Bcalis. 

e.  Ileum. 

/.  Budimcnt  of  mesenteriolum. 

ff.  Vermiform  appendix. 

h.  Fossa  Bub-csBcalis. 

«.  Psoas  magnus. 


PLATE  25. 

Illustratite  op  Me.  C.  E.  Buktok's  Paper  "  Ov  the  Zodiacal  Light." 
Fide  Proceedingi  R.  I.  Acad.,  Vol.  2,  8er.  2,  p.  218. 

Fig.  1.  Represents  the  collective  result  of  the  obseirations  on  the 
spectmm  of  the  Zodiacal  light  detailed  in  the  accompanjring 
paper,  laid  down  on  a  scale  of  wave-lengths.  The  nnit  of 
the  scale  employed  for  designating  the  lines  is  '-  ""'1^**^ ;  the 
same  with  that  used  by  Angstrom.  ^ 

Fig.  2.  The  nucleus  and  envelopes  of  the  Zodiacal  light.  Mauritius, 
1875,  Jan.  2. 

Fig.  3.  The  same  as  seen  on  1875,  Feb.  5,  near  the  Equator. 

Fig.  4.  Do.  do.  Feb.  7. 

Fig.  5.  The  same  as  seen  in  high  N.  latitude,  1875,  March  31. 
N.B. — In  Figs.  2,  3,  4,  5,  dark  shading  represents  light. 


PLATES  26  TO  34. 

Illustkatitb  of  the  Rey.  Eugene  O'Meaba's  Report  "  On  the  Ibish 
DiATOHi.cEA."    Port  I. 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  235. 

PLATE  26. 

Fig.  1.  Melosira  Borrerii,  p.  246. 

2.  „        subflexilis. 

3.  ,,        distans. 

4.  Lysigonium  nummuloides,  p.  248. 

5.  Podosira  montagnei,  p.  250. 
ha,       ff       maculata. 

6.  Orthosira  arenaria,  p.  251. 

7.  ,,.        sulcata. 

6.        „         orichalcea. 
9.        „        Roeseana. 
10.  Cjclotella  Kiitzingiana,  p.  256. 


11. 

Menegliiniana. 

12. 

opercr.lata. 

12». 

„          var. 

13. 

antiqua. 

14. 

rotula. 

15. 

papillosa. 

16. 

Scotica. 

17. 

punctata. 

18. 

CoBcinodiflcus,  oculus  iridii,  p.  260. 

19. 

centralis. 

20. 

peiforatus. 

21. 
22. 

gigas. 
radiolatus. 

23. 
24. 

Gregorii. 
Ehrenbergii. 

25. 

if 

minor. 

26.  Craspedodiscus  coscinodiscu^,  p.  266. 
.  I.  A.  rnoCf  «ER.  II.,  TOL.  n.,  scibxce. 


PLATE  27. 

Fig.  1.  ActinocycluB  Balfsii,  p.  268. 

2.  f,  moniliiormii. 

3.  EapodiflCUB  Argus,  p.  269. 

4.  AnliBciiB  scnlptns^  p.  270. 

5.  Odontodiscns  excentriciLs,  p.  270. 

6.  „  AnglieuB. 

7.  „  HibeniicTiB. 

8.  Biddnlpbia  Bailejii,  p.  275. 
8a.         ,f         aurita. 

9.  „  pulcheHa. 

10.  Amphitetras  antedilaTiaiia,  p.  277. 

11.  Triceratiam  alteroans,  p.  278. 

12.  ,,  ambljoceroe. 

13.  ff  cxigamn. 

14.  Trinacria  regina,  p.  278. 

15.  Isthmia  nerrosa,  p.  279. 

16.  Fragilaiia  maxima,  p.  283. 

17.  Denticula  matabilis,  p.  285. 

18.  Odontidium  mesodon,  p.  287. 

19.  Dimeregramma  distaiiB,  p.  289. 

20.  Plagiogramma  costatom,  p.  290. 


PLATE  28. 

Fig.  1.  Diatoma  grande,  p.  291. 

2.  Ralfaia  tabellaria,  p.  293. 

3.  Rhaphoneis  amphiceros,  p.  295. 

4.  „  Bcutelloides. 

5.  ,,  libtimica. 

6.  Synedra  crystallina,  p.  297. 

7.  ff       folgens. 

8.  ,,       bacnlus. 


9.  Synedra  Bnperba. 

10.        , 

y       ampbieephala. 

11. 

,       investiens. 

12. 

,       acula. 

18. 

,       gracilis. 

14.        , 

y       undulata. 

15. 

f       lonaris. 

16. 

,       biceps. 

17.        , 

,       pulchella. 

18. 

,              ,,         var.  gracilis. 

19. 

,              „           „     acicularis. 

20. 

,              ,,           „    lanceolata. 

21. 

„    linearis. 

22. 

f       capitata. 

23.        , 

,             „         var.  longiceps. 

24.        , 

,       ulna. 

25. 

,          „    var.  oxAynchus. 

26.        , 

,          „       „     ampliirhynehuR, 

27. 

,       longissima. 

28. 

,       obtnsa. 

29.        , 

,       splendens. 

30. 

,              „          var.  radians. 

31. 

32. 

,       salina. 

33. 

,       gallionii. 

34.        , 

,       spathnlata. 

35. 

,       barbatola. 

36.        , 

,       tabulate. 

37. 

,       arcus. 

38. 

,       afflnis. 

39. 

,       Nitzschiodes. 

40. 

,       Franenfeldii. 

41. 

f       putealis. 

42. 

,        Smithii. 

43. 

,       debilis. 

PLATE  29. 

Fig.  1.  Orammatophora  marina,  p.  315. 
2.  ,f  Berpentina. 

8.  Tabellaria  flocculosa,  p.  317. 

4.  TetracycluB  lacustris,  p.  318. 

5.  Rhabdonema  arcuatum,  p.  318. 

6.  Striatella  anipanctata,  p.  320. 

7.  Tessella  interrapta,  p.  320. 

8.  Amphipleura  pellucida,  p.  321. 

9.  Mastogloia  convergcnB,  p.  325. 

10.  f,  CloseiL 

11.  I,  portierana. 

12.  f,  Smithii. 

13.  ff  costata. 

14.  Dickieia  ulvoides,  p.  328. 

15.  CoUetonema  neglectum,  p.  331. 

16.  Berkeleya  fragilia,  p.  331. 

17.  Schizonema  cracigeram,  p.  333. 

18.  ,,  Smithii. 

19.  „  Grevillii. 

20.  f,  obtamim. 

21.  Diadesmia  WiUiamaonii,  p.  837. 

22.  3rebis8onia  Boeckii,  p.  338. 


PTiATE  30. 

.  1.  Nayicula  nobilia,  p.  340. 

2.        , 

,        caidinalia. 

8-         , 

,        yiridis. 

4.         , 

,         alpina. 

5-         f 

,        pacbyptera. 

6- 

y        distans. 

7. 

,        undulata. 

8.                      y 

,        rectangolata. 

9. 

,        Trevelyana. 

10. 

,         oblonga. 

1 1 .  Naviculft  longa. 


12. 

tabellaria. 

13. 

divergens  var. 

14. 

borealis. 

15. 

menapiensis. 

16. 

clepaydra. 

17. 

rupestris. 

18. 

ceres. 

19. 

gibba. 

20. 

„     var.  Boeckii. 

21. 

„       „    parva. 

22. 

hemiptera. 

23. 

apiculata. 

24. 

Brebissoiiii. 

25. 

II          var.  angusta. 

26. 

nodosa. 

26a. 

„      var.  staurophora. 

27. 

icostauron. 

28. 

stauroptera. 

29. 

bacillum. 

30. 

Americana. 

81. 

isocephala. 

32. 

bicapitata. 

33. 

„        var.  crucifera. 

34. 

II          II     constricta. 

35. 

termes. 

36. 

microstauron. 

37. 

crucifera. 

38. 

pinnnlaria. 

39. 

scalaris. 

40. 

coneata. 

41. 

acuminata. 

42. 

retusa. 

43. 

Integra. 

44. 

pachycephala. 

45. 

subcapitata. 

46. 

gracillima. 

47. 

macula. 

48. 

zellensis. 

PTiATE  31. 

ig.  1.  Nayicula  cuspidata,  p.  357. 

2. 

,        falva. 

3. 

,        cuBpis. 

4.        , 

,       rhombica. 

5.         , 

,        cceralea. 

6.         , 

,        decipiens. 

7. 

,       tumenB. 

8. 

,        Tostrata. 

9- 

f        tenmrostns. 

10.         , 

,        ambigua. 

11.         , 

,        spboBiophora. 

12. 

,        qnamerensis. 

13.         , 

/       Davidsomana. 

14. 

,        OTnlam. 

15. 

,        latiuBcula. 

16. 

,        Barkeriana. 

17. 

,        Onmovii. 

18. 

,       ampbisbflBna. 

19. 

,       elegans. 

20. 

f        palbebralis. 

21, 

,        bebes. 

22. 

f        lineata. 

23. 

Uber. 

24. 

,        lacuneata. 

25. 

f        Griindleriaiia. 

26. 

,        iridis. 

27. 

,          „     Tar.  ampbigompbus 

28. 

,          MM    affinis. 

29. 

f        dubia. 

30. 

f        limosa. 

31. 

,             „      var.  truncata. 

32. 

f        undosa. 

33.         , 

,        rsox. 

34. 

,        trochus. 

35. 

,        producta. 

36. 

Navicula  coccononeiformi«. 

37. 

ft 

Kotzchyi. 

38. 

}t 

naxiiiia. 

39. 

>t 

y,        Tar.  linearis. 

40. 

19 

siibula. 

41. 

t9 

translacida. 

42. 

tt 

papUlifera. 

43. 

f1 

libumica. 

44. 

ft 

plumbicolor. 

45. 

>> 

Teneta. 

46. 

>> 

Johnsonii. 

47. 

>> 

simulans. 

48. 

»> 

DelgineiMiB. 

49. 

19 

rhomboides. 

50. 

>> 

serians. 

51. 

»> 

crasBmervia. 

52. 

>> 

dirbynchiis. 

53. 

f» 

rostellum. 

54. 

»> 

Iseyisaiiiia. 

55. 

M 

oblongella. 

56. 

>> 

inctiXTa. 

PTiATE  32. 

ig.l. 

NaTicula  punctulata,  p.  377. 

2. 

»> 

3. 

)> 

hnmeroBa. 

4. 

»> 

n        Tar.  loflcata. 

5. 

»> 

M           ,,   qnadrata. 

6. 

>> 

latisBima. 

7. 

M 

meniflcus. 

8. 

>> 

lucida. 

9. 

l> 

clttthensiB. 

9a. 

>> 

„            Tar.  protlucta, 

10. 

» 

punctata. 

11. 

>> 

lacustris. 

12. 

M 

maculosa. 

13.  Navicula  icatilloidefl. 


14. 

»» 

pnailla. 

15. 

tf 

tomida,  rar.  linearis. 

16. 

tf 

polchra. 

17. 

ft 

fnsca. 

18. 

If 

Smithii. 

19. 

ft 

Collisiaiia. 

20. 

ft 

cstiya. 

21. 

>> 

elliptica. 

22. 

ft 

y.        Tar.  oralis. 

23. 

i» 

clavata. 

24. 

>f 

Hennedyi. 

25. 

n 

nebuloaa. 

26. 

tf 

,y        var.  suborbioularis. 

27. 

i> 

pnetecta. 

28. 

»» 

Morei. 

29. 

tf 

Sandriana. 

30. 

ft 

Franciacse. 

31. 

tf 

Hibemica. 

82. 

»9 

nitesceiiB. 

33. 

>» 

84. 

ft 

Stokesiana. 

35. 

ft 

Wrightii. 

86. 

ft 

apcctabilis,  var. 

PTiATJi;  33. 

'.1. 

Navicula  lyra,  p.  391. 

2, 

tt 

„     var.  elliptica. 

3. 

tf 

„       ,,    Gninovii. 

4. 

ft 

,,       f,    minor. 

5. 

ft 

„       „    seductilis. 

6. 

ft 

,,       f,    constricta. 

7. 

ft 

pygmsBa. 

8. 

»» 

,,         var.  cunciita. 

9. 

tt 

expleta. 

10. 

17 

cynthia. 

1 1 .  Navicula  sansegana. 


12. 

ft 

Arraniensis. 

13. 

t> 

Eugenia. 

14. 

»> 

scutellum. 

15. 

>♦ 

suborbiciilaris. 

16. 

ft 

,,            var.  forficula. 

17. 

»f 

Sohmidtii. 

18. 

tt 

coffeifonnis. 

19. 

ft 

eudozia. 

20. 

ft 

Donkiiiiaiia. 

21. 

ft 

marginata. 

22. 

ft 

Qubciyita. 

23. 

ft 

ATcheriana. 

24. 

ft 

incnrvata. 

25. 

tt 

muBca. 

26. 

ft 

interrupta. 

27. 

ft 

apis. 

28. 

ft 

bombus. 

29. 

ft 

didyma. 

30. 

tt 

splendida. 

31. 

tt 

Gregorii. 

32. 

tt 

Williamsoim. 

33. 

ft 

incisa. 

34. 

ft 

crabro,  var.  denticulata. 

35. 

tt 

Pfitzeriana. 

36. 

ft 

Vickersii. 

PTiATE  34. 

r.i. 

Nayicula  directa,  p.  406. 

2. 

ft 

exilis. 

3. 

tt 

radiosa. 

4. 

tt 

gracilis. 

5. 

ft 

acuta. 

6. 

tt 

peregrina. 

7. 

it 

zostereti. 

R.I.A.  PBOC.y  8BR.  11.,  TOL.  II.,  8CISNCB.  / 


8.  Navieula  Cleviana. 


9. 

»> 

digito-radifita. 

10. 

>» 

Ergftdenflis. 

11. 

jt 

cyprinus. 

12. 

>> 

galvagensis. 

13. 

jt 

Solaris. 

14. 

ft 

Tuidnla. 

15. 

t> 

Heufleri. 

16. 

»» 

Nortbumbrica. 

17. 

»> 

arenaria. 

18. 

»» 

inflexa. 

19. 

>» 

Honganea. 

20. 

>» 

CanwdnB. 

21. 

M 

mtitica. 

22. 

i» 

Bemen. 

23. 

>» 

inflata. 

24. 

M 

Anglica. 

25. 

»> 

cryploeepbala. 

26. 

»» 

angostata. 

27. 

tt 

Lagentedtii. 

28. 

f} 

gaBtarom. 

29. 

yr 

binodifl. 

30. 

Jt 

dioepbala. 

31. 

tt 

32. 

ty 

globifera. 

33. 

ft 

rofltellilera. 

34. 

)i 

cancellata. 

35. 

ti 

minor. 

36. 

»> 

pexpuBilla. 

37. 

11 

seminulum. 

I^.  B. — AU  tbe  figoreB  in  the  preceding  Plates  of  Diatoms  are  mag- 
nified 400  diameters,  unless  otberwise  indicated. 
Fig.  10,  Plate  29.— Tbe  Striae  sbould  be  radiate. 


PLATE  35. 

Illustrative  of  Professor  Edw.  Perceval  Wright's  Paper  *'  Ox  a 
New  Geihts  and  Species  of  Paitoartna." 

Fide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  583. 

rig.  1.  Stasiotes  Rhinodontisy  gen.  et  sp.  nov.     Nat.  size, 
dorsal  aspect, 
side  view, 
ventral  aspect, 
anterior  antenna  x  25. 
rostrum  and  palpi  («)  x  25. 
rostrum  (i)  x  50. 

„         shewing  toothing  {c)  +  200, 
posterior  antenna  x  25. 
first  foot-jaw  x  25:  cheloer  {a)  x  50. 
second  ,,         ,, 
first  abdominal  foot  x  25. 
second         ,,  ,y 

third  „ 

fourth  ,,  ,, 

last  segment  with  appendages. 


2. 

» 

3. 

tf 

4. 

»» 

5. 

M 

6. 

tf 

7. 

tf 

8. 

ft 

9. 

tf 

10. 

tf 

11. 

ft 

12. 

tf 

13. 

n 

14. 

tf 

R.  I.  A.  PROC,  8RR.  II.,  VOL.  II..  SCIEN'CK. 


PLATE  36. 

Illustrative  op  Db.  Kelly's  Paper  **0h  a  Case  of  Polydacttusm." 

Vide  Proceedings  R.  I.  Acad,  Vol.  2,  8er.  2,  p.  539. 

Fig.  1.  I.,  II.,  III.,  IV.,  v.,  VI.    The  metacarpal  bones. 

P.  I.,  P.  II.,  P.  III.    Fint,  second,  and  third  Pollices. 

a,  Posterior  angle  of  Os  Triquetmm. 

h,  Interosseous  ligament,  corresponding  with  the  line  of  junc- 
tion of  the  ''  Complemental  process,"  with  the  Scaphoid 
in  the  left  hand  (fig.  2,  h). 

Cy  Line  of  fusion  between  the  Posterior  Trapezoid  and  the 
Complemental  process. 

d,  The  depression  indicating  the  tendency  to  bifidity  in  the 

second  metacarpal  bone. 
Fig.  2.  P.  I.,  P.  II.,  P.  III.     First,  second,  and  third  Pollices. 

a,  Posterior  angle  of  Os  Triquetmm. 

hf  Line  of  union  between  the  Scaphoid  and  the  "  Complemen- 
tal process." 

e,  The  cartilaginous  ferule  on  apex  of  the  metacarpal  bone  of 

first  PoUex. 
d,  Sesamoid  bones. 

0,  The  united  second  and  third  phalanges  of  third  Pollex. 
Fig.  3.  a,  Anterior  Trapezoid. 

hf  Broken  line  indicating  the  posicion  of  the  Os  Triquetrum. 
Fig.  4.  The  Os  Triquetrum  of  right  hand. 

Fig.  5.  The  two  bones  in  the  left  hand  corresponding  with  the  0» 
Triquetrum  of  the  right  hand. 
0,  The  detached  unciform  process. 


PLATE  37. 

Illtjstratiye  of  Db.  Kelly's  Papes  "  On  a  Case  of  Foltdacttlisv." 

Fids  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  539. 

Fig.  6.  1,  Opponens  Pollicis. 

2,  Abductor  Pollicis. 

3,  The  deeper  and  only  head  of  the  Flexor  Brevis  Pollicis, 

dividing  into  two  slips. 

4,  4,  4,  The  three  divisions  of  the  IntcrpoUicaris. 

5,  Flexor  Pollicis  Secundi  et  Tertii. 

6,  Musculus  Accessorius  ad  Lumbricalem  Primum. 

7,  Adductor  Pollicis. 

8,  Musculus  Accessorius  ad  Transversum  Manum. 

9,  Transversus  Manus. 
Fig.  7.  1,  Opponens  Pollicis. 

2,  2,  2,  The  three  slips  of  the  Abductor  Pollicis. 

3,  3,  3,  The  three  portions  of  the  Flexor  Brevis  Pollicis. 

4,  The  two  portions  of  the  Interpollicaris. 

5,  Musculus  Accessorius  ad  Transversum  Manum. 

6,  Adductor  Pollicis. 

7,  Lumbricalis  ad  PoUicem  Tertium. 


PLATES  38  &  39. 

iLLrSTRATTirE  OF  Dr.  KeLLT's  PaPER  **  On  A  CaSE  OF  POLTDACXYUSM." 

V$de  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  539. 

Plate38,  Fig.  8.  1,  2,  Extensor  Ossis  Metacarpi  Pollicis;  two  slips 
(the  second  Extensor  Intemodii  Pollicis  Primi). 

3,  Extensor  Primi  Intemodii  Pollicis. 

4,  Extensor  Secundi  Intemodii  Pollicis. 

6,  Slip  between  Extensor  Communis  Bigitonim  and 
Extensor  Indicis. 

6,  Aponeurotic  web  between  the  first  and  second 

Pollex,  into  the  free  margin  of  which  -were  in- 
serted some  of  the  muscles  of  the  anterior  group. 
Pig.  9.  1,  2,  3,  Three  slips  of  Extensor  Ossis  Mctacorpi 
Pollicis. 

4,  Extensor  Primi  Intemodii  Pollicis. 

5,  6,  Two  slips  of  Extensor  Secundi  Intemodii  Pol- 

licis. 

7,  Aponeurotic  web. 

8,  Extensor  Indicis. 

Plate  39,  Fig.  10.  The  vessels  and  nerves  of  the  anterior  surface  of 
right  hand. 
Fig.  11.  Ditto,  of  the  left  hand. 

1 ,  The  great  Artcria  Mediana. 


PLATE  40. 

Illustkjltite  op  Db.  Feeceyal  Weight's  Fapbb  "  On  a  New  Gsktts 
Aim  Species  of  Spoitge." 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  754. 

Fig.  1.  Kalispongia  Archcri,  gen.  et  spec,  noy.,  x  50  (side  view). 

2.  ,y  „        front  view  of  head  portion,  x  50,   of 

another  specimen. 

3.  „  „        stem  portion  of  an  apparent  variety, 

x50. 

4.  ,,  „        portion  of  tissue  of  stem,  x  250. 

5.  „  „  „  „      of  head,  x  250. 


R.  I.  A.  fROC,  SEB.  II.,  TOL.  H.,  iClMiiCit; 


PLATE  41. 
Illustb^tite  of  Mb.  Harsmaiv's  Paper  **  On  the  Irish  Cabbokifero  r< 

DOLOIOTBS.** 

Fide  Proceedings  of  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  705. 

Fig.  1.  Rockhead  Quarry,  Lougbrj,  Co.  Tyrone. 

2.  Section  at  Biyenriew,  Co.  Kilkenny. 
a,  a,  a.  Dark  grey  limestone. 

h^  bf  b.  Intervening  layers  of  calcite. 

3.  Dolomite,  near  Jenkinstown,  Co.  Kilkenny,  showing  cellular 

structure  simulating  ''  current  bedding,''  the  cayitiea  filled 
with  oalc-spar. 


PLATE  42. 

tLLUBTRATITE  OF  Ms.  HaBBUAn's  PaPES  **  Ok  THE  IbISH  CaBBOITIFEBOTTS 

Dolomites." 

Fig.  4.  Flan  of  limestones  and  dolomites,  Ballyfoyle,  Kilkenny. 

5.  Section  at  Ballyfoyle,  showing  limestone  passing  into  dolomite. 

6.  Enlarged  section  at  {a),  fig.  6,  showing  passage  of  limestone 

into  dolomite. 


PLATE  43. 

Iixir0TRiTnis  OF  Dk.  Hoobe's  Papxb  ''  Oh  Ibibh  ExbaticmJ' 

Vide  Proceedings  R.  I.  Acad.,  Tol.  2,  Ser.  2,  p.  591. 

Fig.  1.  Lejeunea  patens,  lindberg ;  natural  size. 

2.  „  „        X  15. 

3.  „  „         x30. 

7.  ,,        leaf  and  portion  of  stem,  x  100. 

8.  „        ampbigastriom,  x  100. 

9.  ,,        portion  of  leaf,  mag.  x  400. 

Drawn  from  specimen  supplied  by  Dr.  landbei^. 

4.  „        dorsal  aspect  of  plant,  with  colesiile  and  male  amen- 

tnl»,  X  25. 

5.  „        branch,  with  colesule,  x  50. 

6.  „        ventral  aspect  of  plant,  with  male  amentnbe. 

Drawn  from  plant  collected  at  Glenad,  Co.  Leitrim, 
1875. 


PLATE  44. 

iLLrsTRATiYE  OF  Db.  Moobe's  Papeb  "  Ow  Ibish  Hbpaticjb." 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  591. 

Fig.  1.  Lejennea  Hooreiy  Lindberg;  natural  size. 

2.  „  „     xlO. 

3.  y,        ventral  aspect  of  plant,  showing  colesnles  and  male 

amentnl»,  x  25. 

4.  „        leaf  and  portion  of  stem,  x  50. 

5.  „        ampbigastrinm,  x  100. 

6.  ,,        portion  of  leaf,  x  400. 


PLATE  46. 

IixusTSATrns  of  De.  Moore's  Paper  "  On  Irish  Hxpaticji." 
Fide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  591. 

Fig.  I.  Frallaiiia  Hatchinsud,  P  integrifolia,  Nees;  nataral  size. 

2.  yy  ,y    X  10,  witli  111816  amentulsB  and  colesules. 

3.  „        leaves  and  portion  of  stem,  x  25. 

4.  „         amphigastrium,  x  75. 

5.  „        portion  of  leaf,  x  400. 

6  &  7.  „        portion  of  stem,  leaves  and  amphigastrium  of  typical 
form  of  a.  after  Hooker. 


PLATE  46. 

Illubtbahvb  op  De.  M^Nab's  Papxk  "  Ok  a  Retisioit  of  the  Species 

OF  Abies." 

Tide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  673. 


In  the  Description  of  Plates  46,  47,  48,  and  49,  all  the  figures  are  magnified  20 
diameters.  The  letters  refer  to  all  the  figures— e.  Epidermis,  h.  Hypoderma. 
c.  Resin-canals,    s.  Sheath  of  the  fibro-yascular  bundles. 


Pig.  1.  Abies  bracteata.    From  specimen  cnltiyated  at  Elvaston  Nur- 
series, Borrowash,  Derby. 

2.  ,,      religiosa.    From  specimen  cnltiyated  at  Castle  Ken- 

nedy, N.  B. 

3.  ,,      amabiHs.     From  a  graft,  from  Donglass's  plant,  cnlti- 

yated in  the  Boyal  Botanic  Garden,  Edinburgh. 
3a.     „      amabilis.     Near  Lake  Ghilnkweyak  B.  C. ;  Cascade 
Mountains,  49°  N.  lat.,  Dr.  Lyall,  1859 :  Kew  Her- 
barium. 

4.  ,,      grandis.    From  a  layer,  from  Douglass's  plant,  culti- 

yated  in  the  Eoyal  Botanic  Garden,  Edinburgh. 
4a.    ,,      grandis.     From  a  specimen  raised  from  Jeffrey's  seeds, 
and  cnltiyated  in  the  Boyal  Botanic  Garden,  Edin- 
burgh, as  A.  lasiocarpa. 

5.  „     Lowiana.    From  a  specimen  raised  from  Jeffrey's  seeds, 

and  cnltiyated  in  the  Eoyal  Botanic  Garden,  Edin- 
burgh. 

6.  ,,      concolor.  From Eew Herbarium :  Fendler,  "PI. Novo- 

Mexicano,"  No.  828,  1847. 

7.  „      lasiocarpa.    From  Kew  Herbarium,  "  sp.  typica,"  coll. 

Douglas. 
7a.    „      lasiocarpa.    From  Kew  Herbarium,  unnamed  specimen, 
marked  "  America  Boreali-occidentaliB,"  D*  Douglas. 


PLATE  47. 

iLLvnEiHTS  or  Ds.  M'Nab's  Pater  "  Ok  a  Retisiov  of  thz  Sfbos 

OF  Abibs." 

Vide  Proceedings  B.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  673. 

Fig.  8.  Abies  lasiocarpa.    Sent  by  Mr.  Syme  as  Abies  bifolia,  A.  Mur- 
ray ;  collected  by  M.  Boegl. 
9.      „    ,  lasiocaipa.    East  side  of  Cascade  Mountains,  49^  N.  lat., 
Aug.  1860;  Kew  Herbarium ;  ColTille,  Indian  name 
"  Marcilp." 

10.  ,,      Fraseri.    From  specimen  cultivated  at  Castle  Kennedy, 

KB. 

11.  ff      balsamea.    From  specimen  cultivated  in  the  Boyal  Bo- 

tanic Garden,  Edinburgb. 

12.  ,f      sibirica.    From  a  plant  cultivated  in  Glasnevin  Gtf* 

den,  Dublin. 

13.  ,,      Yeitchii.    Kew  Herbarium. 

14.  „      firma.     Kew  Herbarium :    ''  Japonia,  19'ippon.  1864, 

Maximiowicz." 

15.  ,,      bifida.    From  a  specimen  cultivated  by  Messrs.  Yeitch 

and  Son,  of  Chelsea,  and  sent  under  the  erroneous 
name  of  A.  firma. 

16.  yf      n.  sp.  Harryana.   From  a  specimen  cultivated  by  Messrs. 

Yeitch  and  Son,  of  Chelsea,  and  sent  under  the  erro- 
neous name  of  A.  Yeitchii. 

17.  ,,      Pindrow.    From  a  specimen  cultivated  in  Glasnevin 

Garden,  Dublin. 


PLATE  48. 


Illttbteatitb  of  Db.  M'Nab's  Paper  "  Oit  a  Retisioit  of  the  Species 

OF  Abies." 

Vide  Proceedings  R.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  673. 

Pig.  18.  Abies  Webbiana.     From  a  specimen  cultivated  in  Glasnc- 
vin  GFaxden,  Dublin. 

19.  ,,      sp.    Herbarium,   Trinity  College,   Dublin :   "  Abies 

Webbiana,  Himalaya  occid.,  9000  to  liz^OOO,  Hook, 
fil.  et  Thomson." 

20.  ,,      pectinata.     From  a  specimen  cultivated  in  Glasnevin 

Garden,  Dublin. 

21.  „      pectinata,  var.  Mooreana.    From  a  specimen  cultivated 

in  Glasnevin  Garden,  Dublin. 

22.  „      Nordmanniana.     From  a  specimen  cultivated  in  Glas- 

nevin CFarden,  Dublin. 

23.  „      cilicica.     Herbarium,  Trinity  College,  Dublin  :  Kot- 

schy,  No.  370,   '*  in  regionibus  Danise,  supra  Eden, 
alt.  5000.     Die  28  Jul.  1855." 

24.  „      cepbalonica.    From  a  specimen  cultivated  in  Glasnevin 

Garden,  Dublin. 

25.  f,      cepbalonica,  var.  ApoUinis.    From  a  specimen  culti- 

vated in  the  Royal  Botanic  Garden,  Edinburgh. 

26.  ,,      Pinsapo.     From  a  specimen  cultivated  in  Glasnevin 

Gai'den,  Dublin. 

27.  ,,      Baborensis.     From  a  specimen  cultivated  in  Elvaston 

Nurseries,  Borrovrash,  Derby. 


PLATE  49. 

Illustbative  op  De.  M*Nab'b  Papbb  *'  Ok  a  Bevisiok  of  the  Sfxcizs 

OF  Abies.'' 

Vide  Proceedings  E.  I.  Acad.,  Vol.  2,  Ser.  2,  p.  673. 

Fig.  28.  Abies  sp.  Drummond.    From  a  specimen  cultivated  in  the 
Eoyal  Botanic  Crarden,  Edinburgh. 

29.  Pseudotsuga  nobilis.     From  a  plant  cultivated  in  tlie  Royal 

Botanic  Garden,  Edinburgh. 

29a.        „  nobilis.     From  a  plant  cultivated  in  the  Royal 

Botanic  Garden,  Edinburgh,  and  sent  under 
the  erroneous  name  of  A.  amabilis  of  Douglas. 

293.         „  nobilis.     Leaves  from  Kew  Herbaiium  of  the 

type  specimen  of  P.  amabilis,  Sabine,  Dou- 
glas, sent  by  Professor  Oliver,  F.  R.  S- 

30.  ,,  magnifica.    From  a  plant  cultivated  by  Mr.  An- 

thony Waterer,   Knap  Hill  Nursery,    near 
Woking,  Surrey. 
30a.         „  magnifica.  £ew Herbarium:  <<  441.  150-200 ft. 

Sierra  Nevada,  L.  California.     W.  Lobb." 

31.  M  Fortunei.     From  a  plant  cultivated  by  Messrs. 

Yeitch  and  Son,  Chelsea,  and  forwarded  under 
the  name  of  Abies  Jezoensis. 

32.  ,,  Douglasii.    From  a  plant  cultivated  in  Elvaaton 

Nurseries,  Borrowash,  Derby. 

32a.         „  Douglasii.    Kew  Herbarium  :  **  Eocky  Moun- 

tain, Independence  Bluff.     Nuttall." 

32b.        f,  Douglasii.  Herbarium,  Trinity  College,  Dublin : 

New  Mexico,  Fendler,  No.  829. 


R.I.AProc   Ser.  II.  Vol.11.  Science 


Plate  1 . 


K^^^-^ 


Pnix./ 


I' »«.i. 


^-f5tJ 


Alex  MacalistM    a.d  :.al  oel* 


Minlem  Droe  imp 


Lachrymo  jugaJ     Suture. 


i 


1  A  Pr--c  Ser  II  Vol  U-  ocier.ce 


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1. 


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2. 


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5. 


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12. 


PentastcTTia . 


11. 

13.    ^ 


l^^tem  Bros  amp . 


i 


1  A  Proc  Ser.ll  Vol  11  Science 


Plate  4. 


Alex  MacaJjster  a.d  na-t  def 


MmtwnBros  imp 


Choluepub    didacivlus. 


L  A  Proc,  Ser.lI.Vol  II  Science. 


Plate  5. 


Fig.l. 


Fig. 2. 


Me. 


..1 


Al«x.Mac«litt«r  adiuctdal* 


E«o. 


MmtemBroa  wnp 


Retro -peritoneal    Cavities. 


>  ^P.T.lI,VoV^^  ScieTice. 


f*r.i»r.  4  Kr«Vui«  l-'lh"  V'l'"' 


W  V*"'  ^*'^^ 


f\.Proc.  Ser.  II. Vol .11.  Science. 


Plate 


A  7 


GHKAGH-Ford. 


MmlemBrot  imp. 


^^Proc.  Ser.II.Vol.II.Scienoe. 


Plate  8. 


GilKJcGHiord 


ifintera  Bros.x 


^Pi^ti, 


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fttt  ^f -^ 


f 


R  T  A  Proc  Ser.lI.Vol  11  Science. 


Plate  13 


h      \    c 


'9 
Fig.  3. 


Fig. 6. 


A  M.^  n*t  GHFofd  liih. 


Fig.  1. 


Fig.  2. 


Fig.  4. 


MiBttemBroa 


Bradypus  gularis. 


A  Vr?.:  "--r  I'  Vni  \l  S^i-n-*? 


Plate 


r./itr  tiiut  d«i' 


V'TiT.ar.*  >.Fn>,-«  Lith"id: 


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:jri-i,  uv)- 


1  A  Proc.Ser.  II  Vol  11.  Science. 


Plate  18 


HwrtlilifitUiian  idt.tjitli 


Cave  of  Dunmore,  C?  Kilkenny. 


^.1  A.Proc.  Ser.lI.Vol.II.  Science. 


Plate  '. 


Fig.l. 


Fig. 3. 


/ 


I 


Pig.  7. 


A  M.ad/pat  dii.  GHForA  ktk 


Pig. 2. 


Fig.  4. 


^ 


Fig.  8. 


l&nieni  Bme  ax 


A  Proc.  Ser.Ii  Vol.11.  Science. 


Plate  2C 


Fig.  9. 


Fig. 11. 


Fig.  10. 


Fig.  14. 


Fig. 13. 


Fig. 15. 


A.  U  dd.nfct.  del.  G  H  Ford  lith 


_2foit«rtTvDro9_wiS 


\.Proc.  Ser.II  Vol  U  Science. 


Plate  21. 


Fig.  1. 


Fig    2. 


HV.'.]/«(Lki:iUsna.dTi.i--  iel    ».H Frrrdlith 


JK^^^BrosJmp  1 


i 


-A-Proc.  Ser .II. Vol .11. Science. 


Plate  22. 


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RIA.ProcSer.il  Vol  II  Sciei.ee 


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Fig.l. 


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Mmtern  "Pros  imp  1 


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R  I  A.Ppoc.Ser.Il.VoLIl  Science 


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^v  I  A.rroc.Scr.II  Vol  U  Science 


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"1  i  A  Proc.  Ser  11  Vol.11.  Science 


Plate  41. 


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Stream 


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id  ward,  T.  Hardman.  d«]t  et  liit. 


Forster  i  C!' Ljih  DubJm. 


I  I  A.  Proc.Ser. II. Vol. II. Science 


Plate  42. 


Fig.  4.. 


Pl-aii  of  Limestones  and  Dolomites  BalJvfoyle  Kilkenny. 
Scale  Six  inches  to  one  mile. 


Hg.  5 

Section  at  Ballyfoyle 


S.E. 


;.4(» 


^r-  -  '-^:.^-^^  ,,^,  ^:.-t:^.,,>^^5^- 


sr:sr*  .l^'?;y>ii.. 


"^r--, 


Fig.  6. 

Enlarged  sketch  of  (a)  Fig  5. 


!■  '^  -n  Carboniferous  Limestone. 
,,  Dolomite. 


rc2urdrd.T.Hardia*A.delt  et  lull. 


Forrteri  C«Lah  Dublin. 


-'•  1   AProc.  Ser  II  Vol  H^  S«eiice 


Isle  4-3. 


Tiiffm%atai 


LEJEUNIA    x:?;teii3    Undh 


r'  LA  7r.  ^  St^r  I!.V:L;[.  :;!( 


WW«.iJ*^VHr 


LE JEUNIA      Moopei  Lindb 


.  Froc  3er  1 1.  Vol.  II  Science 


r^^Kl-^-..^ 


t) 


FRULLANL^    Huldimsise  l3  inteqrif:^lK.  NL. 


R  LAProc.  Serll. Vol.11  Science. 


Plate  46. 


RlAR-ocSerll  Vol.n.  Science. 


Plate  4' 


ICnreeila  Irvaa.  6d^  i- 


Scai*    ToB    of    oiM,    Iftrh, 


_4  Jiy/vstSc  Co  m 


^IJ^Troc.  Ser.n.VoI.II.  Science. 


Plate  48 


RIAPpocSepH-VolIL  Science. 


Plate  4.9. 


o 

LIST 

OFTHJE 

COUNCIL  AND   OFFICEES 

AND 

MEMBEES 

OF  THE 

BOYAL     lEISH    ACADEMY; 

DUBLIN, 

IST  OF  September,  1875. 


DUBLIN : 
ACADEMY  HOUSE,   19,   DAWSON   STEEET, 

187J. 


THE  ROYAL  IRISH  ACADEMY, 

A.D.    1875. 


^atrsn: 

HER  MAJESTY  THE  QUEEN. 
HIS  EXCELLENCY  THE  LORD  LIEUTENANT  OF  IRELAND. 


.  ROYAL   IRISH   ACADEMY. 


{Pint  elected,  16th  of  March,  1874.) 
WILLIAM  STOKES,  m.d.,  ll.d.,  d.o.l.,  p.b.b.,  p.k.  &  q.c.p.i. 

C|^^  €onmxl: 

{Elected  16ih  of  March,  1876.) 

The  Ck>iincil  conaistB  of  the  Committees  of  Soience  and  of  Polite  Literatim  and 

Antiquities. 

immtUt  of  Sitmict  (Eleven  Members): 

Blaeted. 

REV.  SAMUEL  HAUGHTON,  m.d.,  p.b.8.,  D.O.L.,  p.t.o.d. 

EDWARD  PERCEVAL  WRIGHT,  m.d.  P.L.S.,  r.B,o.8.i.  (Sec.) 

DAVID  MOORE,  PH.D.,  p.l.8. 

JOHN  CASEY,  LL.D. 

THOMAS  HAYDEN,  p.k.  &  q.c.p.1.,  ex-p.b.c.s.l 

REV.  JOHN  HEWITT  JELLETT,  b.d.,  s.p.t.c.d. 

ALEXANDER  MACALISTER,  m.b. 

SIR  ROBERT  KANE,  M.D.,  ll.d.,  p.b.s.,  p.k.  &q.o.p.i. 

ALEXANDER  CARTE,  m.d.,  P.L.B. 

GEORGE  JOHNSTONE  STONEY,  m.a.,  p.b.s. 

WILLIAM  ARCHER,  P.B.B. 

€mmiiu  of  polite  yittratert  uni  ^ntxtpxititn  (Ten  Members)  : 

JOHN  THOMAS  GILBERT,  P.S.A.,  B.H.A. 

JOHN  KELLS  INGRAM,  ll.d.,  p.t.c.d. 

SAMUEL  FERGUSON,  ll.d.,  q.c. 

WILLIAM  JOHN  O'DONNAVAN,  ll.d. 

ALEXANDER  GEORGE  RICHEY,  ll.d.,  q.c. 

JOHN  RIBTON  GARSTIN,  m.a.  &  ll.b.,  p.8.a.  (See.) 

VERY  REV.  WILLIAM  REEVES,  D.D.,  ll.d.,  m.b..  Dean 

of  Armagh. 
REV.  THADDEUS  O'MAHONY.  d.d. 
REV.  MAXWELL  CLOSE,  m.a. 
ROBERT  ATKINSON,  ll.d. 

This  Council  will  continue  till  March  16, 1876. 


(1)  Mw. 

,  1870 

(2)  „ 

1870 

(8)  ,. 

1872 

(*)  ,. 

1872 

(5)  .. 

1873 

(«)  ,. 

1874 

(7)  „ 

1874 

(8)  .. 

1875 

(9)  „ 

1875 

(10)  „ 

1876 

ai)    .. 

1875 

(12)  Mar., 

1856 

(IS)   „ 

1859 

(H).  ,• 

1867 

(15)    M 

1867 

(16)  ,. 

1869 

(17)  Dec., 

1869 

(18)  Mar.; 

1871 

(19)  „ 

1873 

(20)  „ 

1875 

(21)  ,. 

1875 

9Slitt'Tl^xtBxhtvAB: 


{Aa  wmiMUd  hg  the  PrmdeiU,  16tk  of  Mcrdi,  1875  :  wtk  tkt  data  from  wkkk 
tkey  have  efmiinwmely  been  re-appoiiUtd.) 

1.  VERY  REV.  WILLIAM  REEVES,  d.d.,  ll.d.,  ilb^  Dean  of  Anna^ 

(1874). 

2.  REV.  SAMUEL  HAUGHTON,  m.d^  O.O.L.,  f.b.8.,  f.t.c.d.,  (1871). 

3.  SAMUEL  FERGUSON,  LL.a.  qx.,  (1870). 

4.  SIR  ROBERT  KAKE,  h.d.,  xx.d,  f.b.8.,  (1875). 


f  Elected  annuaUp  hy  (he  Academy  ;  with  datee  offint  eleetiom,) 

(       LL.B.,  F.8.A.,  Q1871;. 

aw«— *.^  (EDWARD  PERCEVAL  WRIGHT, 

^**^*"^^ t     M.A.,  JI.D.,  F.L.a.,  (1874). 

fl«n.— A»^  *.•  «r.  n/.n,nTT  IJOHN    KJELLS    INGRAM,    ll.i>., 

SkJBHABTOFTHICoDWCIL    ....        I      F.T.C.D.,  (1860). 

SlORRABT  OF  FOUDON  GOBBISPOKDENGK  |  WILLIAM  ARCHER,  F.BLB.,  (1875). 

L«BABUK JJOmiTHOMASGILBBBT.TAA.. 

(       B,H.A.,   Vl80l). 


Clerh  of  the  Ac^demg,  {deeted  annuaUg  b»  «**>  Edwabd  Cubbobh.  Esq..  (!«»). 

Academy) ) 

Curoior,  Mtaam^Clerk^  and  Houaekeq>er,         .  Capt.  Robert  MacEhibt,  (1872). 

Iriih  Scribe,        Mb.  J.   O'Lohoak,   (1865). 

Aetietani  AccomUant,        Mb.£dwabdSpkncxb,b.a.,(1878). 

Library  Clerh,        Mb.  J.  J.  MacSwbbotbt,  (1869). 

AuietatU  in  Library Mb.  R.  J.  O'Mulbbnin,  (1872). 

Serjeemi-at'Maee, (FocanfV 

C0mmxttjet8  appointib  %  CrrmtnJ : 

Tkete  OoMMitteee  are  compoetd  of  ikt  Memhera  of  Council,  to  vhoae  namea  the  eubjeimed 
numbera  art  prefixed  in  the  foregoing  liat  : 

Mvaewn,        .     .    Committee  of  Polite  Literature  and  Antiquities.    Sec  No.  17. 
Publieatian,        .    2  (Sec.),  8,  9,  10  ;  12,  13,  17,  20. 
Library,         .    .    2,  8,  6,  8,  11 ;  12  (Sec),  13,  15,  17,  21. 
TriahManuacHpU,  4  ;  12  (Sec.),  13, 14, 15,  17,  18,  19,  21. 
Bco^umyit  ffouae,   2,  4,  5,  6  ;  12,  14,  17  (Sec),  19. 


MEMBERS  OF  THE  ROYAL  mSH  ACADEMY. 


Ordinary  Members. 


The  sign  *  is  prefixed  to  the  names  of  Life  Members. 

The  sign  f  indicates  the  Members  who  have  not  yet  been  formally  admitted. 

N.B. — The  names  of  Members  whose  ctddresses  are  not  hnovm  to  the  Secretary  of 
the  Academyi  are  printed  in  italics.  He  requests  that  they  may  be  oommimicated 
to  him. 


Date  of  Election. 

1866.  Jan.  8 
1843.  April  10 

1871.  June  12 
1873.  Jan.  13 
1839.  Jan.  14 

1842.  Jan.  10 
1828.  April  28 

1870.  Jan.  10 


1816.  Mar.  16 
1875.  Jan.  11 


1863.  June  8 
1872.  April  8 

1866.  June  11 


Adams,  Rev.  Benjamin  William,   D.D.    Cloghran 

Rectory,  Drumcondra,  Co,  Dublin. 
*Allman,  George  James,  Esq.,  M.D.  (Dub.  and  Oxon.), 

Pres.  Lin.  Soc,  F.R.C.S.I.,  F.R.SS.,Lond.  &  Edin. 

Upper  Pkilliinore  Gdrdtiis,  London,  S.W. 
*tAmliurst,  William  A.  Tyssen-,  Esq.,  D.L.,  F.S.A., 

M.R.S.L.     DicUington  Hall,  Brandon,  Norfolk, 
Andrews,  Arthur,  Esq.     Newtown  Home,  Blackrock, 

Co,  Dvhlin, 
♦Andrews,   Thomas,    Esq.,    M.D.,  LL.D.     (Edin.), 

F  Jl.8.,Hon.  F.R.S.  Ed.,  F.C.S.,  Vice-President,  and 

Professor  of  Chemistry,  Queen's  College,  Belfast 

Queen's  College,  Belfast, 
♦Andrews,  William,  Esq.,  F.R.G.S.I.     Ashton,  The 

Hill,  Afonlcstotm,  Co,  Dublin, 
*Apjohn,  James,  Esq.,  M.D.,  F.RS.,  F.  and  Hon.  F., 

K  &  Q.C.P.I.,  F.C.S.,  Professor  of  Mineralogy 

and  of  Applied  Chemistry,  Dublin  Univ.     South 

Hill,  Blackrock,  Co,  Dublin, 
♦Archer,  William,  Esq.,  F.R.S.,  Secretary  of  Foreign 

Correspondence,     St,  Brendan's,  Grosvenor-road, 

E.,  Rathmines,  Co,  Dublin, 
^Ashbumer,  John  F.,  Esq.,  M.D.,  M.R.C.  Phys.  Lon. 
Atkinson,   Robert,  Esq.,  LL.D.,  Professor  of  Ro- 
mance Languages,   Univ.  Dub.      20,    GarviUe- 

avenue,  Rathgar,  Co,  Dublin, 

♦tBagot,  C.  Neville,  Esq.,  J.P.  Augkrane  Castle^ 
Ballygare, 

Baily,  William  Hellier,  Esq.,  F.L.S.,  F,aS.,  De- 
monstrator in  Paleeontology,  R.C.Sci.I.  Apsley 
Lodge,  92,  Rathgar-roady  Co,  Dublin;  14  Humn- 
street,  Dublin, 

Baker,  John  A.,  Esq.,  F.RC.S.L   4,  Clare-st.,  Dublin, 


6 


Royal  Irish  Academy, 


Date  of  Election. 

1872.  June  24      Baldwin,  Thomas,  Esq.  Model  Farm^ Glasnevin,  Co, 

Dublin. 
1840.  Aprill3    *Ball,  John,  Esq.,  M.A.,  F.RS.,F.L.S.     \0,  SoiUh- 

well  Gardens,  South  Kensington,  London,  S,  W, 
1870.  Jan.  10     Ball,  Kobert  Stawell,  Esq.,  LLD.,  F.R.S.,  Andrews 
Professor  of   Astronomy  in  the    University  of 
Dublin,  and  Royal  Astronomer  of  Ireland.     The 
Observatory,  Dunsink,  Co,  Dublin, 
1842.  Jan.    10    ^Banks,  John  T.,  Esq.,M.D.,  F.K.  &Q.C.P.I.     10, 

Merrion-square,  East,  Dublin, 
1851.  April  14    *Barker,  John,  Esq.,  M.D.,  F.R.C.S.L,  F.RG.S.I. 

48,  Waterloo-road,  DuhUn, 
1868.  Jan.  13    *Barker,   W.   Oliver,  Esq.,  M.D.,   M.R.C.S.K     6, 

Grardiners-row,  Dublin, 
1874.  May  11      Barrett,  William  F.,  Esq.,  F.RC.S.E,  Professor  of 
Physics,  Royal  College  of  Science.      9,  Mount- 
pdier-parade,  Monkstown,  Co,  Dublin, 
1866.  May  14     Bamngton,  Sir  John,  D.L.     St,  Anne's,  KiUiney, 

Co,  Dublin. 
1866.  Jan.     9    *Beauchamp,   Robert  Heniy,  Esq.      116,   Grafton- 

street,  Dublin, 
1868.  April  27    *Belmore,  Right    Hon.   Somerset-Richard,  Earl  of; 
M.A.,  D.L.,  K.C.M.G.    Castle  Coole,  EnniskHlen. 
1866.  June  11      Bennett,  Edward   Hallaran,  Esq.,  ■M.D.,   M.Ch., 
F.R.C.S.I.,  F.R.G.S.I.,  Professor  of  Surgery  in  the 
University  of   Dublin.      2Q,    FitzunUiam-street, 
Lower,  Dublin. 
1825.  Nov.  80   *Ben8on,  Charles,  Esq.,  M.A,,  M.B.,  F.R.C.S,L     42, 

Fitzwilliamr square,  (West J,  Dublin, 
1851.  June    8   +Beresford,  Right  Hon.  and  Most  Rev.  Marcus  G.,  - 
D.D.,  D.C.L.,  Lord  Archbishop  of  Armagh,  Pri- 
mate of  all  Ireland.     The  Palace,  Armagh. 
1846.  April  13    *Bevan,  Philip,  Esq.,  M.D.   (Dub.),  Prof,  of  Ana- 
tomy and  Fellow  R.C.S.I.    62,  FitzwUliani'Squart, 
(West),  Dublin. 
1849.  Jan.     8  *tBewglas8,  Rev.  James,  LL.D.   Wakejield,  Yorkshire, 
1843.  Dec.  11    *Bewley,    Edward,    Esq.      Edington,   Clara^  Kings 

County, 
1843.  Jan.     9    *Blacker,  Stewart,  Esq.,  M.A.,  J.P.     Carrick  Blacker, 

Fortadoton. 
1871.  Jan.     9    fBourke,  Very  Rev.  (Canon)  Ulick  J.,  President  of  St. 

Jarlath's  College,  Tuam.     St,  JarlatKs,  Tuam. 
1873.  April  14    fBoyd,  Michael  A.,  Esq.,  F.R.C.S.L,  L.K.  &  Q.C.P.L 
90,  George* s-street.  Upper,  Kingstown,  Co.  Dublin. 
1854.  April  10    *Brady,  Cheyne,  Esq.     {Abroad,J 
1849.  April  9    *Brady,  Daniel  Fredk.,  Esq.,  F.R.C.S.L, SM.R.C.S.E. 

La  Choza,  Rathgar-road,  Co,  Dublin. 
1865.  April  10  |  fBrash,  Richard  Rolt,  Esq.,  Sunday's  WeU,  Cork. 


JM  of  Memhcra, 


Date  of  Electioa. 

1858."Aprill2 
1851.  Jan.  13 
1874.  Feb.    9 

1854.  April  10 

1855.  Jan.  8 
1842.  Jan.  10 
1866.  April  9 


1862.  Aprill4 
1836.  Feb.  22 
1873.  May  12 


1888.  Feb.  12 
1855.  Feb.  12 


1866.  May  14 


1873.  Jan.  13 


1862.  Jan.  13 


1843. 
1842. 


Jan.     8 
June  13 


tBrooke,  Thomas,  Esq.,  D.L.    The  Castley  Lough  Eske, 

Strabafie,  Co.  Donegal. 
*tBrowne,  Robert  Clayton,  Esq.,M.A.,D.L.  Broumes 

Hilly  Carloto, 
tBunlen,    Henry,   Esq.,    M.A.,    M.D.,   M.RC.S.E. 

9,  College-squarey  North,  Belfast, 
Burke,   Sir    John   Bernard  (Ulster),  LL.D.,  C.B. 

Tullamaine  Villa,  Leeson-sireet,  Upper,  Dublin. 
♦Butcher,   Richard    G.,    Esq.,    M.B.,    F.R.C.8.L, 

M.R.C.S.E.    19,  Fitzwilliam'Street,Lotoer,  Dublin. 
/Butcher,  Right  Hon.  and  Most  Rev.  Samuel,  D.D., 

Lord  Bishop  of  Meath.   Ardbraccan  House,  Navan, 
Byrne,  John  A.,  Esq.,  B.A.,  M.B.  (Dub.)    37,  West- 

land-row,  Dublin. 


1864.  Jan.  11 


1842.  Jan.  10 
1857.  April  13 


1842.  Jan. 
1841.  Jan. 


Campbell,  John,  Esq.,  M.D.,  Professor  of  Chemistry, 

C.U.I.     36,  Leinster-road,  Eathmines,  Co.  Dublin, 

*Cane,  Edward,  Esq.,  J.P.    St.  Wolstan's,  CeUnidge, 

Co.  ICHdare. 
fCarlingford,  Right  Hon.   Chichester,  Baron,  D.L., 
Lord  Lieutenant  of  Essex.     Med  House,  Ardee; 
7,  Carlton  Gardens,  London,  S.  W, 
♦Carson,  Rev.  Joseph,  D.D.,  S.F.T.C.D.,  F.R.G.S.L 

18,  FitzwUliam-place,  Dublin. 
Carte,  Alexander,  Esq.,  M.D.,  F.RC.S.L,r.R.G.S.L, 
Director  of  the  Royal  Dublin  Society  Museum  of 
Natural  History.     14,  Read's-road,  Dublin. 
Casey,  John,  Esq.,  LL.D.,  Professor  of  Higher  Ma- 
thematics   and    Mathematical    Physics,    C.U.I. 
Rose  Cottage,  Tivoli  North,  Kingstown,  Co,  Dublin, 
•f  Castletown  of   Upper  Ossory,    Right  Hon.  John- 
Wilson,  Baron,  Lieutenant  of  the  Queen's  County. 
Ldsduff,  Errill,  Templemore. 
^tCather,   Rev.   Robert    G,   LLD.       Nutty  Hogg, 

Wandsworth  Common,  London,  S.  W. 
♦Gather,  Thomas,  Esq.,  J.P.     Newtoumlimavady, 
♦Chapman,  Sir  Benjamin  J.,  Bart.,  D.L.     KiUua 

CastlSf  Clonmdlon. 
Charlemont,  Right  Hon.  James-Molyneux,  Earl  of, 
KP.,  Lieutenant  of  the  County  Tyrone.    Marino, 
Clontarf, 
♦Churchill,  Fleetwood,  Esq.,  M.D.,  F.K  <&  Q.C.P.L 

Ardtrea  Rectory,  Stewartstoum,  Co.  Tyrone. 
^tCleland,  James,  Esq.,  J.P.    Tobar  Mliuire,  Crossgar^ 

Co.  Down. 
*  Clendinning,  Alex.,  Esq. 

♦f  Clermont,  Right  Hon.  Thomas,  Baron,  D.L.  Ravens^ 
dale  Farkf  Newry, 


8 


Royal  Irish  Academy, 


Dftte  of  Election. 

1867rMay  18 

1835.  Nov.  30 
1874.  June  8 

1860.  Jan.  9 

1845.  June  9 

1866.  April  9 

1871.  June  12 

1856.  April  14 

1825.  Nov.  80 
1847.  Jan.  11 

1864.  May  9 

1846.  Jan.  12 

1857.  Aug,  24 

1867.  June  24 
1866.  June  11 
1870.  Apr.  11 

1874.  June  8 

1853.  April  11 
1855.  May  14 

1846.  April  13 

1870.  Jan.  10 
1846.  Jan.   12 


♦Close,  Rev.  Maxwell  R,  M.A.,  F.RG.S.I.    Ntwtoun 

Park,  Blackrock,  Co.  Dublin. 
*C6Uy  Owen  Blayney,  Esq.,  D.L. 
Collins,  Edward  Wolfenden,  Esq.jM.D.    33,  Baggot- 

street,  Lower,  Dublin, 
*Conwell,  Eugene  Alfred,  Esq.,  LL.D.     Cork. 
*Cooke,  Adolphus,  Esq.     Cooksborcugh,  MuUmgoTy 
tCooper,  lieut.  Col.  Edward  H.,  D.K^  MarkreeCasUe, 

Collooney, 
tCooper,  Major  Richard,  (late  Scots  Fusilier  Guards). 

BrixtoorUi,  Northampton. 
Copland,  Charles,  Esq.    Royal  Banky  Foster-pkur, 

Dublin;    7,    Longford-terrace,    Monkstown,    Co. 

Dublin, 
*Corballis,  John  R,  Esq.,  LL.D.,  Q.C.     Rosem^mnt, 

Roebuck,  Clonskeagh,  Co,  Dublin, 
♦Corrigan,  Sir  Dominic  J.,  Bart.,  M.D.,F.K.&Q.C.P.L, 

Corr.  For.  Mem.  Academie  de  Medecine,  Paris. 

4,  Merrion-square,  Wesl^  Dublin. 
tCotton,  Charles  PhiHp,Esq.,  B.A.,  C.E.,  F.RG.S.I. 

11,  Pembroke-street,  Lotver,  Dublin. 
Cotton,  Rev.  Henry,  IxL.D.,  D.C.L.  (late  Archdeacon 

of  Cashel.)    Lismore. 
*Crofton,    Denis,   Esq.,  B.A.      8,  Mountjoy -square, 

(North J,  Dublin. 
*tCrofton,   Henry  Morgan  E,  Esq.,   F.RA.S.,  J.P. 

Inchinappa,  Ashfotd,  Co.  Wieklow. 
fCruise.  Francis  R,  Esq.,   M.D.,    F.K.  &  Q.C.P.L, 

M.R.C.S.K     3,  Merrionsquare,  West,  Dublin. 
Cruise,  Richard  Joseph,  Esq.,  F.RG.S.I.,  Geological 

Survey  of  Ireland.     Boyle,  Co.  Roscommon;  14, 

Hume-street,  Dublin. 
Cryan,  Robert,  Esq., M.D.  54,Rutland-squart,(WestJ, 

Dublin. 

*Davies,  Francis  Robert,  Esq.,    KJ.J.    HauOhom, 

Blackrock,  Co.  Dublin. 
Davy,  Edmund  W.,  Esq.,  M.  A.,  M.D.,  Prof,  of  Med. 

Jurisprudence,   R C.S.I.      Elm  Grove,   Terenure, 

Co.  Dublin;  Royal  College  of  Science,  51,  St.  Stc- 

phen's-green,  (East),  DMin, 
*D'Arcy,  Matthew  P.,  Esq.,  M.A.,  D.L.     6,  Merrum- 

square^  East,  Dublin, 
Day,  Robert,  Esq.,  F.S.  A.  Rockview,Montenotte,  Cork. 
*Deasy,  Right  Hon.  Rickard,  LL.D.,  Third  Baron  of 

the  Exchequer.     CarysfoH  House,  Blackrock,  Co. 

Dublin. 


List  of  Members. 


Date  of  Election. 

1851.  June  9 
1849.  Sept.  9 

1860.  Jan.  9 

1847.  Jan.  11 
1851.  Jan.  13 

1856.  Feb.  11 


1873,  Jan.  18 
1843.  Jan.  9 
1861.  Feb.  11 

1873.  Jan.  13 

1843.  Dec.  11 
1867.  Feb.  11 
1841.  Apiill2 

1846.  Jan.  12 


1870.  Jan.  10 

1867.  April  8 
1854.  Feb.  13 

1834.  Mar.  15 

1842.  Jan.   10 


*tDe  la  Ponce,  Mons.  Amadie.    Paris. 
De  Vesci,  Right  Horn  Thomas,  Viscount,  D.L, 
F.RG.S.I.   Abbeyleix  Houssy  Ahbeykix,  Queen's  Co. 
♦Dickson,  Rev.  Benjamin,  D.D.,  F.T.CD.     3,  KU- 

dare-place^  Dublin. 
*tDobbin,  Leonard,  Esq.    27,  Gardiner' s-place,  Dublin, 
*Dobbin,  Rev.  Orlando  T.,  LL.D.    Chez^moi,  Ctdlens- 
woodj  Co.  Dublin. 
Downing,  Samuel,  Esq.,  C.E.,  LL.D.,  F.R.G.S.L, 
Professor  of  Civil  Engineering,  Dublin  Univ. 
4,  The  Hill,  Monkstown^  Co^  Dublin. 
Drew,  Thomas,  Esq.,  R.H.A.,  F.R.LA.I.     6,  St. 

Stephen' s-green,  (North),  Dublin. 
*Drury,  William  Vallancey,  Esq.,  M.D.     7,  Harley- 

street.  Cavendish-square^  Londony  W. 
Duncan,  James  Foulis,  Esq.,  M.D.,  Fellow  and  Pre- 
sident, K.&Q. C.P.I.     8,  Merrion-street,  Upper^ 
Dublin. 
Durham,  James  Samuel  William,  Esq.,  F.R.G.S.I. 
Babbacombey  Torquay,  South  Devon. 

*tEiffe,  James  S.,  Esq.,  F.R.AstS.    The  Chestnuts, 
near  Amersham,  Buckinghamshire, 
Ellis,  George,  Esq.,  M.B.,  F.R.C.S.I.     91,  Leeson- 
street,  Lower,  Dublin. 

*Emly,  Right  Hon.  William,  Baron,  Lieutenant  of  the 
County  Limerick.  Tervoe,  Limerick;  Athenceum 
Club,  London,  S.W. 

♦Enniskillen,  Right.  Hon.  William- Willoughby,  Earl 
of,  LL.D.,  D.C.L.,  D.L.,  F.R.S.,  F.R.G.S.L, 
Trustee  of  the  Hunterian  Museum,  RC.S.,  Lon- 
don. Florence  Court,  Co.  Fermanagh;  66,  Eaton- 
place,  London,  S.  W, 

tEsmonde,  Sir  John,  Bart.,  M.P.,  D.L.  Ballynas' 
tragh,  Gorey,  Co.  Wexford. 

*Farrell,  Thomas  A.,  Esq.,  M.A.     3,  MenriMi-squarey 

East,  Dublin. 
♦fFerguson,  Rev.  Robert,    LL.D.,  F.  S.  A.,  F.R.S. 
15,    Carlton  HUl^  East,  St.  John*s-Wood,  Lon- 
don. 

♦Ferguson,  Samuel,  Esq.,  LL.D.,  Q.C.,  a  Vice-President 
of  the  Academy.  20,  Georges-street,  Great,  Norths 
Dublin. 

♦Ferrier,  Alexander,  Esq.  Knochmaroon  Lodge,  Cha- 
pelizod,  Co.  Dublin. 


10 


Eoyal  Irish  Academy. 


Date  of  ElcctiDB 

l857rAng.  24 

1870.  May  23 

1841.  April  12 

1875.  Jan.  11 

1851.  June    9 

1860.  Jan.  9 
1874.  May  11 

1866.  April  9 

1874.  Feb.  9 
1838.  Kov.  12 
1866.  May  14 

1865.  AprillO 
1847.  May  10 

1873.  April  14 


1866.  April  9 
1859.  Jan.  10 

1845.  April  14 

1866.  June  11 
1864.  Jan.  11 

1863.  Feb.  9 


1851.  Jan.   18 
1855.  April  9 

1874.  April  13 
1858.  June  14 

1875.  April  12 


Fitzgerald,  Right  Bev.  William,  D.D.,  Lord  Bishop 

of  Killaloe,  &c.     ClarUford  House^  KiUaloe. 
tFitzGibbon,  Abraham,  Esq.,  M.I.C.E.  Lond.     The 

Rookery^  Great  Stanmore,  Middlemx. 
^Fitzgibbon,  Gerald,  Esq.,  M.A.,  blaster  in  Chancery. 

10,  Merrion'square,  Norths  Dublin. 
Fitzpatrick,  William  John,  Esq.,  J.R,  LLD.     75, 

FembrQke-road,  Dublin, 
Fleming,  Christopher,  Esq.,  M.D.,  r.RC.8.L     6, 
Aferrion-squarft  Norths  Dublin. 
tFoley,  William,  Esq.,  M.D.,  M.R.C.8.E.     KilrudL 
Foot,  Arthur  Wynne,  Esq.,   M.D.,  F.K.Q.C.P.L, 

F.RG.S.I.     21,  Fembroke-street,  Lower,  Dublin. 
Forrest,  John  K,  Esq.,  L.K.Q.C.P.L,  F.RC.S.I. 
13,  Clare-street,  Dublin. 
fFoster,  Rev.  NicholBS.  BaUymacelliy^&etory,  Tralee. 
*Frazer,  George  A.,  Esq.,  Captain  R.N. 
Frazer,  WiUiam,  Esq.,  M.D.,  F.RC.ai.,F.RG.S.L 
20,  Harcourt  street,  Dublin. 
fFreeland,  John,  Esq.,  M.D.     Antigua,   West  Indies. 
♦Freke,  Henry,  Esq.,  M.D.  (Dub.),  F.K.&Q.C.F.I. 

68,  Mount-street,  Lower,  Dublin. 
•f  Frost,  James,  Esq.,  J.  P.      BaUynvorris,CraJUoe,  Co. 
Clare. 

Gaffney,  Rev.  James.    Coolock,.Co.  Dublin. 
Gages,  Alphonse,E8q., Chev.  L.H.,  F.R  G.S.L  Boyal 
CoUegeofScience,  5 1  St.  Stephen's  green,  {East),Dublin. 
♦Galbraith,    Rev.    Joseph  Allen,  M.A.,   F.T.C.D., 

F.RG.S.I.     8,  Trinity  College,  Dublin. 
fGallwey,  Thomas,  Esq.,  J. P.     KiUamey. 
Garnett,  George  Charles,  Esq.,  B.A.     5,  Mountjoy- 
square,  (North),  Dublin. 
♦Garstin,  John  Ribton,  Esq.,  M.A.,  LL.B.,  F.8.A., 
F.R  Hist.  Soc,  Hon.  F.RI.A.L,  J.P.,  Treasurer  of 
the  Academy.     Green-hill,  KiUiney,  Co.  Dublin. 
Gibson,  James,  Esq.,  M.A.,  Q.C.     35,  Moantjoy^ 
square,  (South),  Dublin. 
♦Gilbert,    John    Thomas,    Esq.,    F.S.A.,   RttA., 
Librarian  of  the  Academy.     ViUa  Nova,  Black- 
rock,  Co.  Dublin. 
tGoold,  Ernest  H.,  Esq.,  C.E.     35,  Lady-lane,  WaUr^ 
ford;  18,  Queen  Victoria-street,  London,  B.C. 
Goold,  Yen.  Frederick,  M.  A.,  Archdeacon  of  Raphoe. 
University  Club,  17,  St.  Stephen* s-green,  (North), 
Dublin. 
tGore,  J.  E.,  Esq.,  C.E.     Umballa,  Puf^aub. 


List  of  Members, 


11 


Dftte  of  Bleotlon. 

ISSeTMay  25 

1848.  June  12 
1848.  AprillO 
1863.  Apiilld 

1887.  April  24 

1860.  May  14 

1874.  Feb.  9 
1867.  April  8 

1872.  April  8 

1824.  Mar.  16 
1819.  April  26 

1842.  Jan.  10 

1889.  Jan.  14 

1870.  April  11 

1873.  Dec    8 

1836.  April  26 

1875.  Jan.  11 
1867.  April  8 
1847.  Jan.  11 
1850.  April  8 

1837.  Feb.  18 

1874.  Dec.  14 

1861.  May  13 
1867.  Aug.  24 


*Gougli,  Eight  Hon.  George  S.,  Viscount,  M.  A.,  D.L., 

F. L.  S. ,  F.G.S.  St.  Belen's,  Booteratomiy  Co.  puhlin. 
*Graham,  Andrew,  Esq.     Observatory,  Cambridge. 
*Graham,  Rev.  William.    Dresden. 
tGranard,  Eight  Hon.  George -Arthur-Hastings,  Eari 

of,  KP.     Castle  Forbes,  Co.  Longford, 
*Graves,  Eight  Eev.  Charies,  D.D.,  Lord  Bishop  of 

Limerick,  &c.     Ihe  Palace,  Henry-street,  Limerick. 
Graves,  Eev.  James,  B. A.     Inisnag  Glebe,  Stonyford, 
Co.  Kilkenny. 

Gray,  William,  Esq.    6,  Mouvt- Charles,  Belfast. 
Green,  James  S.,  Esq.  Q.C.     S3,Leeson-8treet,  Louxr, 

Dublin. 
tGreene,  John  Ball,   Esq.,  C.E.,   F.RG.S.I.,  Com- 
missioner of  Valuation.     6,  Ely-place,  Dublin. 
*Grierson,  George  A.,  Esq.     Malahide,  Co.  Dublin. 
♦Griffith,  SirEichard,  Bart.,  LL.D.,  F.E.S.Ed.,  F.G.S., 

V.P.R.G.S.L     2,  Fitzudlliam-place,  Dublin. 
*Grimshaw,  Wrigley,  Esq.,  F.R.C.S.I.     2,  Novara- 

terrace,  Bray. 
♦Grubb,  Thomas,  Esq.,  F.RS.     141,  Levnster-road, 

Rathmines,  Co.  Dublin. 
t Guinness,  Sir  Arthur  E.,  Bart.,  M.A.,  M.P.,  D.L. 

18,   Leeson- street y  Lower;  St.  Ann^s,   Clontarf, 

Co.  Dublin. 
♦Guinness,  Edward  Cecil,  Esq.  M.A.,  D.L.     80,  St. 

StepherCs-green  ( South)  ^  Dublin. 

♦Hamilton,  Charles  William,  Esq.,  J. P.     40,  Domi- 
nvck-street,  Lower,  Dublin. 
HamUton,   Edward,   M.D.,  F.RC.S.L      120,    St. 
Stephen* s-green,  (West),  Dublin. 
♦Hanagan,  Aiithony,  Esq.      Luckington,  Dalkey,  Co. 
Dublin. 
Hancock,    William  Neilson,   Esq.,    LLD.      64b, 
Gardiner'Street,  Upper,  Dublin. 
•Hardinge,  William  Henry,  Esq.    Woodlands,  Roches^ 

town-avenue,  Monkstown,  Co.  Dublin. 

♦Hart,  Andrew  Searle,  Esq.,  LL.D.,  S.F.T.C.D.     71, 

St. Stephen*8'green,(Soutk);  Trinity  College,  Dublin. 

♦Harvey,  Eeubeu  Joshuah,  Esq.,  M.D.     7,  Merrion" 

street,  (  Upper),  Dublin, 

HatcheU,  John,  Esq.,  M.A,   J.P.      12,  J/cmbn- 

square,  South,  Dublin. 
Hayden,   Thomas,   Esq.,  F.K.&Q.C.P.L,  Prof,  of 
Anatomy  and  Physiology,  C.U.I.     30,  HarcourU 
street,  Dublin, 


12 


Eayal  Iri$h  Academy. 


OAtooCElMlioo. 

leisfl^b.  24 


1852.  Aprill2 

1870.  AprilU 
1840.  Juno   8 

1861.  Jan.  18 

1865.  Feb.  18 

1871.  Feb.  18 
1878.  Jan.  18 
1881.  Mar.  16 
1867.  Feb.  11 
1875.  Jan.  11 
1847.  Aprill2 
1851.  June  9 
1861.  April  8 
1824.  Feb.  28 
1875.  June  11 

1866.  June  11 

1847.  Jan.  11 


♦Haughton,  Rev.  Samuel,  M.A.,  l^LD.,  D.C.L.  (Oxon.), 
F.RS.,  F.G.S..  F  B.G.S.I.,  F.K  &  Q.C.P.L,  Hon. 
F.RC.S.L,  F.T.C.D.,  Professorof  Geology  in  the 
UnivexBity  of  Dublin,  a  Vice-President  of  the 
Academy.     Z\^  Baggot-gtrtet^  Uppery  DuhUfU 

♦Head,  Henry  H.,  Esq.,  M.D.,  F.K.  &  Q.C.P.L, 
ExF.RC.S.!.,  F.R.G.S.I.  7,  FUzwOUamr-sgwiir 
(EaH),  DfibUn. 

fHeily,  John  Yickers,  Esq.,  M.D.  Luaduran  Cot" 
tage^  Riuhtoorthy  Melbourne^  Victoria, 

♦Hemans,  George  Willoughby,  Esq.,  C.K,  F.G.S. 
1,  Westminster  Chambers,  Victoria-Hreety  London^ 
S.W.;  17,  Olaucester-street,  Upper,  Dublin. 

♦Hennessy,  Henry,  Esq.,  F.RS.,  Professorof  Applied 
Mathematics  and  Mechanics  in  the  Royal  Collie 
of  Science  for  Ireland,  St.  Stephen's-green,  Dub- 
lin.   Mount  Eagle,  Sandyford^  Co.  DuJUul 

♦Hennessy,  William  Maunsell,  Esq.  11,  Gardiner  b- 
place,  Dublin. 

tHenry,  Rev.  P.  Shuldham,  D.D.,  President  Q.C., 
Belfast    Queen*8  College,  Belfast. 
Hickie,   James   Francis,  Lieut.-Col.  (retired)^  J.P. 
SUvoir^  Boscrea,  Co.  Tipperary, 

♦Hill,  Lord  George  Augusta.  Ballpare HousCy  Bath' 
melton,  Letterkenny,  Co.  Donegal. 

tHiJl,  John, Esq., C.R,  F.RG.S.I.  County iShmfeyw's 
Office,  JSnnis. 

tHill,  Arthur,  Esq.,  B.E.,  A.RI.B.A.  22,  Georges- 
street,  Cork. 

♦Hone,  Nathaniel,  Esq.,  M.A.,  F.RG.8J.,  J.P.  £^. 
DoulougKs,  Co.  Dublin. 

♦fHone,   Thomas,   Esq.,  J.P.     Yapton,   Monkstown- 
avenue,  Monkstovm,  Co.  Dublin. 
Hudson,    Alfred,  Esq.,   M.D.,  F.K.  &  Q.C.P.L, 
F.RG.S.I.     2,  Merrion-square,  North,  Dublin. 

♦Hudson,  Henry,  Esq.,  M.D.,  F.K.  &  Q.C.P.I. 
Glenville,  Fermoy. 

tHume,  Rev.  Abraham,  Canon,  D.C.L.     AU  SouUf 
Vicarage,  Liverpool. 
Hutton,Thomas  Maxwell,  Esq.,  J.P.   3,  FitzwilUam- 
place,  Dublin. 

♦Ingram,  John  Kells,  Esq.,  LL.D.,  F.T.C.D.,  Regius 
Professor  of  Greek  in  the  University  of  Dublin, 
Secretaryof  Council  of  the  Academy.  2,  WeUing- 
ton-road,  Dublin. 


List  of  Memben. 


13 


Date  of  Eleetlon. 

184irAprill2 
1842.  June  13 

1867.  April  8 

1868.  Jan.  12 
1870.  Dec.  12 

1831.  Nov.  30 

1873.  Dec.  8 
X865.  April  10 

1869.  Jane  14 

1870.  June  13 
1867.  Feb.  11 
1864.  Nov.  14 

1888.  June  24 

1870.  May  23 

1886.  Jan.  25 

1869.  Nov.  8 
1846.  April  13 
1848.  April  10 

1838.  May  14 

1874.  May  11 
1866.  April  9 

1868.  Jan.  13 
1863.  April  13 


♦Jellett,    Rev.   John   Hewitt^    B.D.,    S.F.T.C.D., 

F.R.G.8.I.   64,  Leesofirstreet,  Lower,  Dublin, 
♦Jennings,   Francia    M.,   Esq.,  F.G.S.,  F.RG.S.I. 

Broum-streety  Cork, 
Jephson,  Robert  H.,  Esq.     Mount  ErroU,  Danny- 
brook,  Co,  Dublin, 
Joyce,  Patrick  Weston,  Esq.,  LL.D.     7,  St,  Ed- 
ward^ s-terrace,  Garville-avenue,  Ratkgar, 
t Joyce,  Robert  D.,  Esq.,  M.  D.    21,  Dotodoinstreet, 
Boston,  Mass,,  U.S.,  America, 

♦Kane,  Sir  Robert,  M.D.,  LL.D.,  F.K.  &  Q.C.P.L, 

F.R.S.,  F.R.G.S.L,  F.C.S.,  a  Vice-President  of 

the  Academy.     21,  Raglanrroad,  Dublin, 
♦Kane,  Robert  Romney,  Esq.,  M.A.     76,  Harcaurt- 

street,  Dublin. 
Kane,  William  Francis  De  Yismes,  Esq.,  M,A.,  J.P. 

Drumreaske  House,  Monaghan, 
Kavanagh,  Very  Rev.  James  B.,  D.D.  St,  Patricias 

College,  Carlow, 
♦Keane,   John  P.,   Esq.,   C.E.,    Engineer,    Public 

Works  Department,  Bengal.     Calcutta, 
Keane,  Marcus,  Esq.,  J.P.     Beech  Park,  Ennis; 

83,  Harcourt'Street,  Dublin^ 
♦Keenan,  Patrick  J.,  Esq.,  C.B.,  Resident  Commis- 
sioner,   Board  of  National  Education,  Ireland. 

DdvUlf,  Glasnevin,  Co,  Dublin, 
♦Kelly,  Denis  Henry,  Esq.,  J.P.    Araghty  Orange, 

Fuerty,  Roscommon. 
♦Kelly,  John,  Esq.,  L.M.  (Dub.).    University  College 

Hospital,  Calcutta, 
♦Kelly,  Thomas  F.,  Esq.,  LL.D.,  J.P.    10,  Newtoumr 

smith,  Kingstown,  Co.  Dublin. 
tKelso,  John  Johnston,  Esq.,  M.D.,  M.  Ch.   Litbum. 
♦Kennedy,  James  Birch, Esq.,  J.P.   Gara,byKUlamey. 
♦Kenney,  James  Christopher  F.,  Esq.,  J.P.    Clogher 

House,  BaUyglass^  Co.  Mayo;  Kilclogher,  Athmry, 

Co.  Galway;  2,  Merrion^squarc,  Souths  Dublin. 
♦Kent^  William  Toderick,  Esq.,  M.A.  61,  Rutland- 

square,  (  West),  Dublin, 
fKidd,  Abraham,  Esq.,  M.D.     BaHymena, 
♦ELinahan,  Edward  Hudson,  Esq.,  J.P.  11,  Merrion' 

square.  North,  Dublin, 
Kinahan,  George  Henry,  Esq.,  F.R.G.S.L     Somer- 

ton,  Wexford;  Geological  Survey  Ofioe,  14,  Hume- 
street,  Dublin. 
Kinahan,  Thomas  W.,  Esq.,  B.A.  2,  Abercorfi'4erraee 
Circular-road,  North,  Dublin. 


u 


Royal  Irish  Ac<idemy. 


Date  of  Electtonr 

1845.  June  8 

1837.  Feb.  13 
1835.  Nov  80. 

1864.  Aprilll 


1875. 
1833. 


1864. 
1836. 
1857. 

1857. 
1839. 
1852 


May  10 
Nov.  30 


Jan.  11 
Jan.  25 
May  11 

April  13 
May  13 
May  10 


1845.  Feb.  10 


1846. 
1844. 


May  11 
April  8 


1828.  April  28 


1869. 
1853. 

1870. 

1868. 

1832. 


April  12 
Aprilll 

June  13 

April  27 

Feb.  27 


♦King,  Charies  Croker,  Esq.,  M.D.,  F.R.C.S.I.     1, 

Belgrave-placef  Cork, 
*KnoXf  George    J.,  Esq. 
*Kyle,WillianiCotter,Esq.,LL.D.  S,Clar€''8L, Dublin, 

♦Lalor,  John  J.,  Esq.,  F.RG.S.I.  City  Hall,  Cork- 
kill,  Dublin, 

f  Lane,  Alexander,  Esq.,  M.D.     Ballynioney. 

*Larcom,  Right  Hon.  Sir  Thomas  Aiskew,  Bart, 
Major-General,  KC.B.,  B.E.,  LL.D.,  F.K.S., 
F.E.G.S.I.,  an  Honorary  Member  of  the  Academy. 
ffeathjieldy  Fareham,  Hants. 
LaTouche,  J.  J.  Digges,  Esq.,  M.A.  1,  Ely-place, 
Upper,  Dublin, 

♦LaTouche,  William  Digges,  Esq.,  M.A.,  D.L.  84, 
St,  Stephen' s-green,  (North),  Dublin, 

♦Lawson,  Right  Hon.  James  A.,  LL.D.,  Justice  of  the 
Court  of  Common  Pleas.  27,  FUzwHUam-street, 
Upper,  Dublin, 

♦Leach,  Lieut.-Colonel  George  A.,  R.E.  3,  SU  James  9- 
square,  London,  S,W. 

♦fLeader,  Nicholas  P.,  Esq.,  J.P.      Drcmagh  CaUle, 
Kanturk, 
Leared,  Arthur,  Esq.,  M.D.  (Dub.),  F.RCJP.  Lond., 
and  Physician  to  the  Great  Northern  Hospital 
12,  Old  Burlington-street,  London,  W, 

♦LeFanu,  WiUiam  R,  Esq.,  C.E.  59,  FUgwiUiam- 
square,  (North),  Dublin, 

♦Lefroy,  George,  Esq.    (Abroad.) 

♦fLeinster,  Hw  Grace  Charles- William,  Duke  of. 
Chancellor  of  the  Queen's  University  in  Ireland, 
and  President  of  the  Royal  Dublin  Society.  Car- 
ton, Maynooth, 

^fLenigan,  James,  Esq.,  M.A.,  D.L.  Castle Fogarty, 
Thurles. 

♦Lenihan,  Maurice,  Esq.,  J.P.    Limerick. 
Lentaigne,  John,  Esq.,  C.B..  M.B.,  J.P.,  FRG.S.L 

1,  Denmark-street,  Great,  Dublin. 
Leonard,  Hugh,  Esq.,  F.G.S.,  F.RG.S.L    Geological 
Survey  of  Ireland,  14,  Hume-street,  Dublin. 

♦Little,  James,  Esq.,  M.D.,  L.RC.S.L,  F.K.& 
Q.C.P.L     24,  Baggot-^treet,  Lower,  Dublin. 

♦Lloyd,  Rev.Humphrey,D.D.,D.C.L.(Oxon.),F.RSS. 
Lond.  and  Edin.,  V.P.RG.S.L,  Y.P.RD.&,  Mem- 
ber of  the  German  Order  "For  Merit,"  Provost 
of  Trinity  College,  Dublin.  Frovosfs  House,  Dvb- 
lin;   Victoria  Castle,  KUlinoy,  Co.  Dublin, 


lA8t  of  Memhtrs. 


15 


DAteot  Election. 

1846rjan.  12 
1876.  April  12 

1845.  Feb.  10 

183a  Feb.  12 

1868.  Jan.  18 
1851.  May  12 

1878.Aprill4 

1871.  Feb.  18 
1857.  Aprill8 
1853  April  11 
1875  Jan.  11 
1874.  Feb.    9 

1873.  Jan.  13 

1864.  April  11 

1826.  Feb.  24 

1827.  Mar.  16 

1857.  Feb.    9 

1865.  April  10 

1856.  June  9 
1871.  April  10 
1831.  Feb.  28 

1874.  April  13 


London, 
Southtll,  RaUvminea, 


\i  Earls- 


♦Lloyd,  William  T.,  Esq.,  M.D. 
Lombard,  James  F.,  Esq.,  J.P. 

Co,  Dublin, 
*Longfield,  Rev.  George,  D.D.,  F.T.C.D. 

forirUrrace^  Dublin, 
♦tLongfield,  Right  Hon.  Moontifort^  LL.D.  (late  Judge 

in  the  Landed  Estates'  Court).    47,  FitzwiUiam- 

square,  (West),  Dublin, 
Lyne,  Robert  Edwin,  Esq.   Sandymount,  Co,  Dublin, 
♦Lyons,  Robert  D.,  Esq.,  M.B.,  F.K  &  Q.C.P.L, 

Prof,   of  Medicine,   C.U.L      8,  Merrion-square, 

Westy  Dublin. 

Macalister,  Alexander,  Esq.,  MB.,  L.R.C.S.I.,  L.E.  & 
Q.C.P.L,  F.RG.S.L,  Professor  of  Comparative 
Anatomy  and  Zoology  in  the  University  of  Dublin. 
15.  Palmerston'road,  Upper  Raihminsa,  Co,  Dublin* 

♦Macartney,  J.  W.  Ellison,  Esq.,  M.P.,  J.P.    The 
Palace,  Clogher, 
Mac  Carthy,  Denis  Florence,  Esq.     106,  Baggot- 
street.  Lower,  Dublin, 

♦McCarthy,  James  Joseph,  Esq.,  R.H.A.  Charles* 
ton  House,  Eathmines,  Co,  Dublin, 

fMac  Carthy,  John  G.,  Esq.,  M.P.     Harbour  View- 
Terrace,  St.  Lukes,  Cork. 
McClure,  Rev.  Edmund,  M.A.     67,  Lincoln' s-Jnn 
Fields,  L<mdon,  W.C, 

♦McCready,  Rev.  Christopher,  M.A.  29,  Orosvenor* 
road,  West,  Rathgar,  Dublin. 

♦McDonnell,  Alexander,  Esq.,  M. A.,  C.E., F.R.G.S.L 
St,  John's,  Island-bridge,  Co,  Dublin. 

*MacdonneU,  James  S.,  Esq.,  C.E. 

*Mac  Donnell,  John,  Esq.,  M.D.,  F.RC.S.L, 
F.RG.S.L    32,  Fitrwilliam'Street,  Upper,  Dublin, 

♦McDonnell,  Robert,  Esq.,  M.D.,  F.R.G.S.L,  F.R.S. 
14,  FembrokC'Street,  Lou>er,  Dublin. 

tMac  Donnell,  Lieut. -CoL  William  Edward  Arm- 
strong, Yice-Lieutenant  of  the  County  Clare.  Ifew 
Hall,  nearEnnis. 

*Mac  Ivor,  Rev.  James,  D.D.,  F.R.G.S.L    Moyle, 

Newtoumstewart, 
Macnaghten,  Colonel  Francis  Edmund  (Late  8th 
Hussars).    Loivther  Lodge,  Balbriggan. 

""MacNeiU,  Sir  John,  LL.D.,  F.R.S.,  F.RA.S.     7, 
Kensington-s^uare,  London,  W, 
KcSmney,  Stephen  Myles,  Esq.,  M.D.     1,  Hume- 
street,  Dublin, 


16 


Royal  Iriik  Academy. 


Drta  of  Eleokloo. 


1846. 
1864. 

1870. 
1874. 
1832. 


186d. 
1859. 


1828. 
1871. 
1840. 
1861. 


1858. 
1860. 


Feb.  28 
Jane  13 

Jan.  10 
Feb.  9 
Oct  22 


April  10 
Jan.  10 


Mar.  15 
Jan.  9 
Jan.  13 
Jan.  14 


Jan.  11 
Jan.  9 


1845.  June  23 


1861. 
1869. 
1866. 
1874. 


Jan.  14 
Feb.  8 
April  9 
Feb.    9 


1840.  Feb.  10 

1844.  June  8 
1854.  May  8 
1872.  June  24 


«Madden,  Richard  R.,  Esq.,  F.R.C.S.  £ng.  1,  Vemtm- 

terrace^  BooUntown-avewue^  BooUntowny  Oo.  Dublin. 

Madden,  Thomas  More,  Esq.,  M.D.,  L.KQ.C.P.L, 

M.R.aS.K,  L.F.P.S.,  Examiner  in  Midwifery, 

etc.,  Q.U.I.     33,  Merrion'Sjuarej  South,  Dublin. 

Mahaffy,    Rev.   John  Pentland,  M.A-,  F.T.C.D. 

38,  Otorg^S'Street,  Oreat,  North,  Dublin, 
Malet,  Jolm  Christian,  Esq.,  M.A.     TrinUy  CoUe^, 
Dublin. 
♦Mallet,   Robert,   Esq.,  M.A.,    M.  Eng.,  PL    R, 
M.LC.E.,  F.R.S.,  F.G.S.,  F.R.G.S.L     16,  The 
I        Grove,  dapham-road^  London^  S, 
l^tMalone,  Rev.  Silvester.    KiOcee, 
♦Manchester,  His  Grace  William-Drogo,  Duke  of. 
1,  OrttU  Stanhope-etred,  London;  Rimbolton  Castle^ 
St.  Neofs,  Hunts;  The  Cattle,  Tanderagee. 
♦Martin,  Yen.  John  Charles,  D.D.,  Archdeacon  of 

Kilmore.     KiUUhandra, 
Maunsell,  George  Woods,  Esq.,  M.A.,  D.L.,  V.P. 

RD.S.     10,  Merrion-tquare,  South,  Dublin. 
Mollan,  John,  Esq..  M,D.,  F.K.&Q.C.P.I.,F.R.G.&L 
60,  FitzunlHam-square,  (North),  Dublin. 
fMondc,    Right    Hon.    Charles-Stanley,  Viscount, 
G.  C.  M.  G. ,  Lieutenant  of  Dublin  City  and  County. 
CharlevilU,  Bray,  Oo.  Wickiow. 
^Montgomery,  Howard  B.,  Esq.,  M.D. 
Moore,  Alexander  G.  Monl^mery,  lieut -Colonel, 

4th  Hussars.     India. 
♦Moore,  David,  Esq.,  Ph.  D.,  F.L.S.,  Director  of  the 
Botanical    Gardens,  Glasnevin.      Glamevinf  Cfo. 
Dublin. 
Moore,  James,  Esq.,  M.D.,  M.RC.S.E.    7,  Chutes- 
I        ter-street,  Bdfcut. 

♦Moran,  Most  Rev.  Patrick  F.,  D.D.,  Bishop  of  Ossory. 
i        St  Kyran's  College,  Kilkenny, 
I    More,  Alexander  Groodman,  Esq.,  F.L.S.   S,  Botanic 
I        View,  Olaenevin,  Co.  Dublin. 
Moss,Richd.J.,£sq.  7S,Eenilv>orth'Square,Rathgar. 

♦Napier,    Right  Hon.   Sir  Joseph,  Bart,  D.C.L., 
LL.D.,  Vice-Chancellor  of  Dublin  University. 
4,  Merrion'square,  South,  Dublin. 
♦Neville,   John,   Esq.,   C.E.,   F.R.G.S.L     Jooelyn^ 

street,  Dundalk, 
NeviUe,  Parke,  Esq.,  C.E.    58,  Fembrohe-road,  Dub- 
lin. 
Nolan,  Francis,  Esq.,  A.RI.A.L    Ardeevin,  Qlena- 
gearyt  Kingdoum,  Com  Dublin. 


LUt  of  Memher9. 


17 


Date  of  Election. 

ISTsTjim.  18 

1846.  Jan.  12 

1869.  June  14 

1869.  June  14 

1876.  Jan.  11 

1867.  June  10 

1833.  May  27 
1867.  Jan.  14 

1865.  Apr.  10 

1869.  Apr.  12 

1866.  June  8 

1867.  May  13 
1866.  June  25 
1857.  June  8 
1869.  Apr.  12 
1866.  Jan.  8 


1869.  Apr.  12 
1844.  June  10 


1871.  Apr.  10 

1861.  June  10 
1870.  Jan.  10 


1866.  June.  11 
1888.  Dec.  10 


Nolan,  Joseph,  Esq.,  F.R.G.S.I.,  Geological  Survey 
of  Ireland.     14,  Hume-street,  Dublin, 
^fNugent^  Arthur  R.,  Esq.    (Fortaferry,  Co,  Down). 

♦O'Brien,  James  H.,  Esq.     SU  Lorcaris,  Eowth,  Co. 
Dublin. 
O'Callaghan,  John  Cornelius,   Esq.      1,   Rutland- 

streeif  Upper^  Dublin. 
O'Callaghan,  J.  J.,  Esq.,  F.RI.  A.I.     21  Cambridge- 

road,  Rathminea,  Co.  Dublin, 
O' Conor  Don,  The,  D.L.,  M.P.     Clonalis,  Castlerea, 
Co.  Boicommon. 
♦CDell,  Edward,  Esq.,  J. P.     Carriglea,  Dungarvan. 
O'Donel,  Charles  J.  Esq.,   J. P.     47,  Leeton-tireet, 

Lofwer,  Dublin. 
O'Donnavan,  William  J.,  Esq.,  LL.D.     University 
Clvh,  17,  St.  Stephen' s-green,  (North),  Dublin;  54, 
Kenilworth-squarey  Bathgar,  Co.  Dublin. 
tO'Ferrall,  Ambrose  More,  Esq.     Balyna,  Enfield. 
*0'Grady,  Edward  S.,  Esq.,  B.A.,  M.B.,  M.  Ch., 
F.R.C.S.1. 105,  St.  Stephen's-green^fSouth),  Dublin. 
tO'Grady,    Standish  H.,   Esq.     8,   Duke-street,  St. 
Jamjtis,  London,  S.  W. 
O'Hagan,  John,  Esq.,  M.A.,  Q.C.     22,  FttmUliam^ 

street,  Upper,  Dublin. 
O'Hagau,  Right  Hon.  Thomas,  Baron.    34,  Butkmd- 

square,  (West),  Dublin, 
O'Hanlon,  Rev.  John.     Presbytery,  Exchange-street, 

Loufer,  Dublin. 
O'Kelly,  Joseph,  Esq.,  M.A.,  F.RG.S.L,  Geological 
Survey  of  Ireland.     7,   Warwick-terrace,   Leeson 
Park,  Dublin  ;  14,  Hume-street,  Dublin. 
O'Laverty.  Rev.  James,  P.P.  Holywood,  near  Belfast. 
*01dham,  Thomas,  E8q.,LL.D.,  F.R.S.,  F.G.S.,Hon. 
F.R.G.S.I.,   Superintendent   of  the    Geological 
Survey  of  India.     Calcutta. 
O'Looney,   Brian,  Esq.,  Professor  of  Irish,  C.U.I. 
Catholic  University, ^b, St.  Stephens-green, (South), 
Dublin, 
*0'Mahony,  Rev.  Thaddeus,  D.D.,  Prof,  of  Irish  in 
Dublin  University.     87,  Trinity  College,  Dublin. 
O'Reilly,  Joseph  P.,  Esq.,  C.E.,   Prof,  of  Mining 
and  Mineralogy,  Royal  Coll.  of  Science,  Dublin. 
68,  Park-avenue,  Sandymount,  Co.  Dublin, 
O'Rourke,  Rev.  John.     Maynooth. 
*Orpen,  John  Herbert,  Esq.,  LL.D.     68,  Stephen' s» 
green,  (East),  Dublin, 


18 


HaycU  Irish  Academy, 


Date  of  Electton. 

ISToTFeb.  14 


1866.  Jan.    8 

1839.  June  10 
1873.  Feb.  10. 
1847.  Feb.    8 

1872.  Apr.    8 

1841.  Apr.  12 
1843.  Dec.  11 

1863.  Apr.  13 
1870.  Apr.  11 

1838.  Feb.  12 

1849.  Jan.     8 

1851.  Jan.  13 

1864  Jan.  11 
1862.  Apr.  14 

1873.  Jan.  13 
1875.  Jan.  11 

1862.  Apr.  12 
1836.  Apr.  25 

1873.  Jan.  13 

1864.  June  13 


(ySbanghnessy,  Mark  S.,  Esq.,  F.R.S.L.,  Begins 
Prof,  of  English  Law,  Queen's  Ck>llege,  Cork,  and 
one  of  the  Examiners,  Q.U.L  19,  Gardiner  s- 
place,  DtMin. 

O'SuUivan,  Daniel,  Esq.,  Ph.  D.  9,  Eden-parl, 
Sandycovef  Kingstown^  Co.  Dublin* 

*Parker,  Alexander,  Esq.,  J. P.     46,    Upper  Bath- 

mineSf  Co,  Dublin. 
Patterson,  William  Hogh,  Esq.     Dundela,  Strand- 
town,  Belfast. 
^tPereira  [elected  as  Tibbs],  Rev.  Henry  Wall,  M.A., 

F.  S.  A.  Scot .,  &c,    Donuington  Lodge,  Ifiey,  Oxford, 
Phayre,  Msyor-General  Sir  Arthur  Purves,  K.C.S.L, 

C.  B. ,  Gro  vemor  of  the  Mauritius.    **  Care  ofMesvrt, 

H,  S.  King  and  Co,,  46  PaU  Mall,  London,  A  IF." 
*Phibbs,  William,  Esq.     Seajleld,  Sligo, 
*Pickfoixi,  James  H.,  Esq.,  M.D.,  M.R.C.SE.,  D.L. 

1 ,  Cavendish-place,  Brighton, 
Pigot,  David  R.,  Esq.,  M.A.     Dundrum   House, 

Dundrum,  Co,  Dublin, 
Pigot,  Thomas  F.,  Esq.,  C.K,  Prof,  of  Descriptive 

Geometry,  etc.,  Royd  College  of  Science,  Dublin. 

4,  Wellington-road,  DubUn. 
*Pim,  George,  Esq.,  J. P.    Brennanstown,  Cabinteeiy, 

Co,  Dublin. 
'^Pim,  Jonathan,  Esq.     Qreenhank,  Monkdoum^  Co, 

Dublin, 
^Pim,    William  Harvey,  Esq..     Monkstown  House, 

MonJcstounuCo.  Dublin. 
*fPoore,  M^jor  Kobert,  (Late  8th  Hu8sar8)i    (Abroad.) 
*Porte,  George,  Esq.      43,   Brunswick-street,   Great, 

DiMin. 
♦Porter,  Alexander,  Esq.,  M.D.,  F.R.C.S.,  Aaaist- 

Surgeon,  Lidian  Army.     Madras. 
fPorter,  George  Homidge,  Esq.,  M.D.,  Sutgeon  in 

Ordinary  to  the  Queen  in  Ireland.     3,  Merrionr 

square,  North,  Dublin. 
*  Porter,  Henry  J.  Ker,  Esq. 
*Porter,  Rev.  Thomas  Hamblin,  D.D.     Desericreat^ 

Tullahogue,  Dungawnon. 
Powell,  George  Denniston,  Esq.,  M.D.,  L.R.C.S.L 

76,  Leeson-street,  Upper,  Dublin, 
fPower,  Sir  Alfred,  KC.B.,  M.A.,  Vice-President  of 

the  Local  Government  Board  for  Ireland.     35, 

Raglan-road,  Dublin. 


List  of  Metnberi. 


19 


Dftte  of  Election. 

1875rAprill2 

1854.  June   9 

1874.  Dec.  14 
1858.  Jan.  11 

1867.  Jan.  14 


1873.  Feb.  10 
1846.  Dec.  14 


1848.  Feb.  13 
1875.  Jan.  11 

1839.  Apr.    8 
1867.  Apr.    8 

1855.  Apr.    9 

1816.  Feb.  14 


1844.  June  10 
1870.  Nov.  30 

1872.  Apr.    8 

1868.  Feb.  10 

1843.  Jan.     9 

1853.  Jan.  10 


*tPower8court,    The    Eight    Hon.    Lord  Viscount. 
Potoerscourty  Enniskerry,  Bray, 
Pratt,  James  Butler,  Esq.,  C.E.     Brununaj  County 
Leitrim 
*tPurcell,  Mathew  John,  Esq.  (Burton^  Co,  Cork). 
Purser,  John,  jun.,  Esq.,  M.A.     Zoto,  Blackrock, 
Co.  Dvblin;  6,  Mountpleatant,  Belfast. 

♦fRead,  John  M.,  General,  U.S.;  Consul-Greneral  of 
the  U.S.A.  for  France  and  Algeria,  Member  of 
American  Fhilos.  Soc.,  Fellow  of  the  Eoyal  Soc. 
of  Northern  Antiquaries,  &c,    Athem, 
Beadmn,  Thomas  Allison,  Esq.,  F.G.S.,  C.E. 
♦Eeeves,  Very  Rev.   William,  D.D.,  M.B.,  LL.D., 
Dean  of  Armagh,  a  Vice-President  of  the  Aca- 
demy. The  Public  Library^  Arfnagh ;  Bectory,  Tynan. 
*Benny,  Henry  L.,  F.R.G.S.L,  lieut.  R.E.,  (Retired 
List).    IQuebecA] 
Reynolds,  J.  Emerson,    Esq,  M.D.,  Professor  of 
Chemistry  in  the  University  of  Dublin.      52, 
Leeson-str^ety  Upper^  Dublin. 
*Bhod€8,  Thomas,E8q.,C.E.,F.RA.S.,Hon. M.LC.E. 
Richey,  Alexander  George,  Esq.,  LL.D.,  Q.C.   27, 

Pembroke-street^  Upper,  Dublin. 
Ringland,  John,  Esq.,  M.D.  (Dub.),  F.K.  &  Q.C.P.L 
14,  Harcourt'Streety  Dublin. 
*Robinson,  Rev.  Thomas  Romney,  D.  D.,  F.  R.  S., 
F.R.Ast.S.,  Hon.M.LC.KLon.,  Hon.M.LCE.L, 
Hon.  M.  Cambridge  Phil.  Soc,   Hon.  M.  Acad. 
Palermo,  Hon.  M.  Acad.  Philadelphia,  Hon.  F. 
RG.S.L,  Royal  Medallist,  R.S.,  1862,  Director  of 
Armagh  Observatory.     Observatory,  Armagh. 
*Roe,  Henry,  Esq.,  M.  A.     (Isle  of  Man. J 
Rosse,  Rt.  Hon.  Lawrence,  Earl  of,  D.L.,  D.C.L., 
V.P.R.S.,  F.R.  Ast.  S.     Birr  Castle,  Parsonstotm, 
tRowley,  Standish  G.,  Esq.,  J.P.,  M.RS.L.    Sylvan 
Park,  KeUs,  Co.  Meatk. 
Russell,  Very  Rev.  Charles  William,  D.D.,  Presi- 
dent of  the  Royal  College  of  St.  Patrick,  May- 
nooth.     The  College^  Maynooth. 

♦Salmon,  Rev.  George,  D.D.,  D.C.L.  (Oxon.),  LL.D. 
(Cantab.),  F.R.S.,  and  Royal  Medallist,  1868, 
Regius  Professor  of  Divinity  in  the  University  of 
Dublin.     81,    WeUingUm'Toad,  Dublin. 

♦Sanders,  Gilbert,  Esq.  Albany  Grove,  Monksioum, 
County  Dublin. 


20 


Royal  IritK  Academy, 


Date  of  BmUod. 

1851."*  May  12 
1848.  Feb.  14 

1846.  Feb.  9 
1873.  Jan.  18 

1847.  Jan.  11 

1869<  Apr.  12 

1861.  Apr.  8 
1885.  Feb.  23 

1868.  Jan.  IS 

1838.  Apr.  22 
1873.  Jan.  13 

1867.  Jan.  14 

1873.  April  14 
1846.  Apr.  13 
1858.  Apr.  11 

1874.  Dec.  14 

1871.  Jane  12 
1834.  Nov.  29 


1874.  June  22 
1857.  Jane   8 


*SayerB,  Rey.  Johnston  Bridges,  LL.  D.   Vdort^  Madras 
tSegrave,  O'Neale,  Esq.,  D.L.     KilUman,   Newtoum-' 

mountkennedy. 
*tShenard,  James  Corry,  Esq.      Kinnerdey  Manor^ 

ReigaU,  Surrey. 
♦fShirley,  Evelyn  Philip,  Esq.,  M.A.,  D.L.,  F.S.A. 

Lough   Fea,    Carriekmacross ;    Lower  Eatington 

Parky  Strat/ord'On-Avan, 
♦Sidney,  Frederick  J.,  Esq.,  LL.D.,  F.RG.S.I.,  Sec- 

retary  of  the  Royal  College  of  Science,  Dublin. 

19,   Herhert'Urtet,  Dublin. 
Sigerson,  George,  Esq.,  M.D.,  M.Ch.,  F.L.S.,  Pro£ 

of  Botany,  C.U.I.     17,  Richmtrnd-hiUy  Eaihmines, 

Co.  Dublin. 
Sloane,  John  Swan,  Esq.,  C.E.     Woodlands,  Fatr- 

view,  Co.  Dublin;  21,  Wegtmoreland-strtet,  Dublin. 
♦Smith,    Aquilla,    Esq.,  M.D.,   F.K   &  Q.C.P.I., 

King's  Prof,  of  Materia  Medica  and  Pharmacy, 

Dub.  Univ.     121,  BaggoUitreet,  Lower ^  Dublin. 
fSmith,  John  Chaloner,  Esq.,  C.E.  Engmeer^s  Ojfiit, 

Dublin,  Wickhw  and  Wexford  EoMlway,  Bray. 
♦Smith,  Joseph  Huband,  Esq.,  M.A. 
Smyth,  Patrick  James,  Esq.,  M.P.,  Chev.  L.  H. 

15,  Belgrave-equare,  East,  Rathmines,Co.  Dublin. 
Smythe,  William  Barlow,  Esq.,  M.A.,  D.L.  Barba- 

villa  House,  CoUindown,  KtUucan. 
♦Smythe,  William   James,    Major  -  General,    RA., 

r.R.S.     AiheTUBum  Club,  London,  S.  W. 
♦Stapleton,    Michael   H.,    Esq.,    M.B.,    F.RC.S.I. 

1,  Mounijoy-flace,  Dublin. 
♦Stewart,  Henry  H.,  Esq.,  M.D.,  F.RC.S.L      75, 

EccleS'Street,  Dublin. 
Stewart,  James,  Esq.,  M.A.  (Cantab.),  Professor  of 

Greek  and  Latin,  C.U.I.     21,  Ckirdiner's- place, 

Dublin. 
Stokes,  Whitley,  Esq.,  LL.D.,  Secretary  to  the  Su- 

preme  Council  of  India.   LegidaUve  Council  ffotue^ 

Calcutta. 
♦Stokes,  William,  Esq.,  M.D.,  D.C.L.  (Oxon.),  LLD. 

(Camb.  and  Dub.),  F.RS.,  F.K  &  Q.C.P.L,  Regius 

Prof,  of  Physic  in  the  Univ.  of  Dublin,  Member 

of  the  German  Order  "  For  Merit,*'  President  of 

the  Academy.    5,  Merrum-square,  North,  Dublin. 
Stokes,  William,  Jun ,  Esq.,  M.D,,  M.Ch.    3,  Clare- 

street,  Dublin. 
♦Stoney,  Bindon  B.,  Esq.,  C.E.,F.RG.S.L    42,  Wd- 

lington-road,  DMin. 


List  of  Members, 


21 


Bate  of  Eleetton.    i 

ISSeTApr.  14 

1857.  Aug.  24 
1874  Apr.  13 
1845.  Feb.  24 
1871.  Jan.     9 

1845.  June  28 


184a 
1863. 


Feb.  14 
Jan.  12 


1846.  Jan.  12 


1866. 
1869. 

1869. 
1864. 


June  11 
Apt.  12 

June  14 
Mar.  16 


1846.  Feb.    9 


1816. 
1871. 


Feb.  14 
June  12 


1868.  Jan.  13 


1834.  May  26 
1870  Nov.  30 
1836.  Jan.  25 


Stoney,   George  Johnstone,  Esq.,   M.A.,   F.R.S., 

Secretary  to  the  Queen's  University  in  Ireland. 

Weston,  Dundrumy  Go.  Dublin. 
♦Sullivan,  William  Kirby,  Esq.,  Ph.D.,  President  of 

Queen's  College,  Cork.     Queen^s  College,  Cork. 
tSweetman,  H.  S.,  Esq.     8,  Abbey  Gardens,  Abbey- 

road,  St.  John's  Wood,  London,  iT.  W. 
*Sweetman,  Walter,  Esq.,  J.P.     4,  Mountjoy-square, 

(N(ynh),  Duhlin. 
tSymons,  John,  Esq.     72,  Queen-street,  Hull. 

♦Talbot  de  Malahide,  Right  Hon.   James,    Baron, 
D.C.L.,D.L.,  F.RS.,F.S.A.,  F.G.S.,  F.R.G.S.I., 
F.R  Hist  Soc,  Pres.  ArchasoL  Inst.     The  Castle, 
Malahide,  Co.  Dublin. 
♦fTarrant,  Charles,  Esq.,  C.E.     Waterford. 

Taylor,  Colonel  Meadows,  C.S.I.,  V.P.R.G.S.I  C.E., 
M.  R.  A.  S. ,  J.  P.  Oldcourt,  Harolds-cross,  Go.  Dublin. 

♦Tenison,  Colonel  Edward  King,  M.  A.,  Lieutenant  of 
the  County  Roscommon.  Kilronan  Castle,  Kea- 
due,  Carrich-on- Shannon. 

fThom,  Alexander,  Esq.,  J.P.     Donnycamey  House, 
Artane,  Co.  Dublin. 
Tichbome,  Charles  Roger  C,  Esq.,  F.C.S.L.     27, 
Waltham 'terrace,   Blackrock,    Co.    Dublin;  Apo- 
thecaries^ Hall,  40,  Mary-street,  Dublin, 
Tobin,    Sir   Thomas,   F.S.A.,  D.L.     BaUincollig, 

Cork. 
Trench,  Right  Hon.  and  Most  Rev.  Richard-Chene- 
vix,  D.D.,  Lord  Archbishop  of  Dublin,  Primate 
of    Ireland.       J%«   Palace,    St.    Stephens-green, 
(N(yrth),  Dublin. 

*Tuffnell,  Thomas  Joliflfe,Esq.,  F.R.C.S.I.,M.RC.S.E. 
58^  Mount-street,  Lower^  Dublin. 

^Turner,  William,  Esq. 

^Tyrrell,  Colonel  Frederick,  J.P. 

Urlin,  Richard  Denny,  Esq.   12,  Leeson-park,  Dublin. 

♦Vandeleur,  Colonel  Crofton  M.,  D.L.  4,  Rutland- 
square,  (East),  Dublin, 

tVentry,  Right  Hon.  Dayrolles-Blakeney,  Baron, 
D.L.     Bumham- house.  Dingle,  Co,  Kerry. 

*Vignoles,  Charles  Blacker,  Esq.,  Mem.  Inst.  C.E. 
Lond.,  F.R.S.,  F.R,A.S.  21,  Duke-street,  West- 
minster, London,  S.W. 


22 


List  of  Members, 


Date  of  Slaction. 

ISTSriTn.  13 
1864.  Feb.  8 
1873.  June  23 


1866. 

1857. 

1851. 

1874. 
1839. 


Apr.    9 

June   8 

Jan.  13 

June  8 
June  10 


1862.  Jan.  13 


1873. 
1839. 

1837. 
1866. 

1844. 
1855. 


April  14 
Jan.  14 

Jan.    9 
Jan.     8 

June  10 
Nov.  12 


1857.  Aug.  24 


tWard,  Robert  Edward,  Esq.,  D.L.     Bang<yr  Cagtle, 

Bangor,  Belfast, 
♦tWarren,  James  W.,  Esq.,  M.  A.     39  HuOand-square, 
(West),  Dublin, 
Warren,  William  H.,  Esq.,  M.D.,  L.RC.ai,  LK  & 
Q.  C.  P.  I.      37,  WesUand-raw,  Dublin;  P.  and 
O,  Steam  Nar.  Co.,  Southampton, 
Westropp,  W.    H.    Stacpoole,   Esq.,    L.RC.S.L, 

F.R.G.S  I.,  &c.     Lisdoonvama,  Co.  Clare, 
♦Whitehead,  James,  Esq.,  M.D.,  F.RC.S.E.,  M.R.C. 
Phys.,  Lon.     87,  Mosley-street,  Manchester, 
♦tWhitUe,  Ewing,  Esq.,  M.D.,  M.R.C.S.E.  1,  ParUa^ 
ment-terrace,  Liverpool, 
Wigham,  John  R,  Esq.     35,  Capd-street,  Dublin. 
*Wilde,  Sir  William  Robert  Wills,  M.D.,  F.RC.S.L, 
M.RS.  of  Upsala,  Surgeon  Oculist  to  the 'Queen 
in  Ireland.     1,  Merrion-square,  Worthy  Dublin. 
Wilkie,  Henry,  Esq.     Belgrave  Eouse^  Monkstown' 
avenue,  Co.  Dublin. 
tWilkinson,  Thomas,  Esq.  Enniscorthy,  Co,  Weacford. 
♦Williams,  Richard  Palmer,  Esq.,  F.RG.S.L     38, 

Dame-street.,  Dublin. 
♦Williams,  Thomas,  Esq.     38,  Dame-street,  Dublin, 
♦Wilson,  Henry,  Esq.,  F.RC.S.L    29,  Baggotstreet, 

Lower,  Dublin. 
♦Wilson,  Robert,  Esq.     28,  Waterloo-road,  Dublin. 
♦Wright,  Edward,  Esq.,  LL.D.     16,  Hyde-Gardens, 

Eastbourne. 
Wright,  Edward  Perceval,  Esq.,  M. A., M.D.,F.L.S., 
Professor  of  Botany  and  Keeper  of  the  Herbarium, 
Dublin  University,  F.RC.S.L,  Secretary  of  the 
Academy.  Herbarium,  Trinity  College,  Dublin  ; 
50,  Lansdovme-road,  Dublin. 


BoycU  Irith  Academy . 


23 


HONORARY   MEMBERS. 


Date  of  Eleetioii. 

1863.  June  22 


His  Eoyal  Highness  Albbbt-Edwabd,  Fringe  of 
Wales. 


"  ThjB  Presidint  of  thb  Rotal  Socistt,  and  Ex-Pbksidknt8  of  ihe  icme, 
are  ahoayteontidered  Honorary  Members  of  the  Academy," — By-Lawy,  ii.,  14. 


1869.  Mar.  16 

(Elected  Hon.  Uem. 
In  Sec  of  Sdenoe 
orlglnallf.) 

1863.  Mar.  16 


1882.  Nov.  30 

(Elected  Hon.  Mem. 
in  Fee.  of  Sc&ance 


Hooker,  Joseph  Dalton,  M.D.,  C.B.,  F.R.S.,  D.C.L., 
LL.D.,  V.P.L.S.,  F.G.S.,  Director  of  the  Royal 
Gardens,  Kew,  President  op  the  Eotal  Society. 
KeWy  Londofiy  W, 

Sabine,  General  Sir  Edward,  R.A.,  K.C.B.,  D.C.L., 
LL.D.,  V,P.  and  Ex-President  OP  the  Royal  So- 
ciety, Hon.  F.RS.,  Edin.,  F.RA.&,  F.L.S.,  &c. 
13,  Ashley'placej  Westminster^  London,  S,  W, 

Airy,  Sir  George  Biddell,  KG  B.,  D.C.L.,  LL.D., 
Ex-President  OF  the  Royal  Society  (1871),  As- 
tronomer Royal,  V.P.  R.  Ast.  S.,  &c.  The  Moyal 
Observatory f  Greenwichy  London j  8.E. 


SRUnOIS  07  8CIEHCE. 

[Limited  to  30  Members,  of  whom  one-half  at  least  must  be  foreigners.] 


1878.  Mar.  15 


1874.  Mar.  16 

1875.  Mar.  16 
1869.  Mar.  16 

1869.  Mar.  16 
1873.  Mar.  15 


1866.  Mar.  16 
1866.  Mar.  16 
1875.  Mar.  16 


Adams,  John  Couch,  LL.D.,  (Dub.)  F.R.S.  and  Cop- 
ley Medalist,  V.P.R.  Ast.  S.,  F.C.P.S.,  etc.,  Direc- 
tor of  the  Observatory  and  Lowndsean  Professor 
of  Astronomy  and  Geology  in  the  University  of 
Cambridge.  Observatory^  Cambridge, 
Berthelot,  Marcelin  Pierre  Eugene.    Boulevard  Saint- 

Michely  57,  Paris. 
Bertrand,  Joseph.     Paris. 
Bunsen,  Robert  Wilhelm  Eberard,  Ph.D.,  For.  Mem. 

R.S.     Heidelberg. 
Cams,  Prof.  Victor  J.     Leipsic, 
Cayley,  Arthur,  LL.D.(Dub.),  F.R.S.,V.P.  R.  Ast.  S., 
&c.,  Sadlerian  Professor  of  Mathematics  in  the 
University  of  Cambridge.     Cambridge. 
Chasles,  Michel,  For.  Mem.  RS.    Rue  du  Bac,  62, 

Paris. 
Clausius,  Rudolph  Julius  Emmanuel,  For.  Mem.  RS. 

Zurich. 
Gotta,  Bernard  von.    Freiburg. 


24 


EoycU  Irish  Academy. 


HONORARY  MEMBERS— Con^'ntierf. 


Dftte  of  Election. 

18737Mar.  15 


1866.  Mar.  16 
1869.  Mar.  16 

1863.  Mar.  16 
1841.  Mar.  16 


1875.  Mar.  16 
1864.  Mar.  16 
1878.  Mar.  15 

1874.  Mar.  16 

1864.  Mar.  16 
1874.  Mar.  16 
1864.  Mar.  16 
1852.  Nov.  30 
1873.  Mar.  15 

1873.  Mar.  15 

1869.  Mar.  16 

1873.  Mar.  15 


1842.  Mar.  16 
1867.  Mar.  16 


8ECTI0H  OF  SCIESCE— Continued 

Dana,  James  D wight,  LL.D.,  &c.,  Professor  of  Geo- 
logy and  Mineralogy  in  Yale  College.  Tale  Col- 
legCf  U,  S,j  America. 

Darwin,  Charles,  F.RS.,&c.  DounifBeckenham^''KeHt, 

Daubr^,  Prof.  Gabriel  Augoste.  Ecole  des  Mines^ 
Paris, 

Dove,  Heinrich  Wilhelm,  For.  Mem.  R.S.    Berlin. 

Dumas,  Jean  Baptiste,  For.  Mem.  RS.,G.C,L,H.,  Se- 
cretdire  perpetuel  de  Flnstitut  de  France.  Rue 
St,  Dominique^  69,  Paris. 

Gray,  Asa.     Cambridge,  Mass.,  U.  S.,  America, 

Helmholtz,  Hermann  Louis.     Heidelberg. 

Hofmann,  August.  Wilhelm,  Professor  of  Chemistry 
in  the  University  of  Berlin.    Berlin. 

Huxley,  Thomas  Henry,  M.D.,  LL.D.,  Fellow  and 
Secretary  of  the  R,S.     London. 

Hyrtl,  Carl  Joseph.     Vienna. 

Lamont»  Johann,  Von.     Munich, 

Le  Verrier,  Urbain  Jean  Jos.    A  V  Ohservatoire,  Paris, 

Regnault^  Henri  Victor.     For.  Mem.  RS.    Paris. 

Schimper,  Wilhelm  Philipp,  Professor  of  Geology  in 
the  Univeraity  of  Strasbui^g.    Stra^mrg. 

Secchi,  Padre  Angelo,  Director  of  the  Astronomical 
Observatory  at  Rome,  For.  Mem-  R.  S.     Romt. 

S^uard,  Charles  Edouard  Browne-,  M.D.,  F.RC.P., 
F.R.S.      Rue  Gay-Lussac,  28,  Paris. 

Stokes,  George  Gabriel,  D.C.L,  LL.D.  (Dub.),  Fel- 
low and  Secretary  of  the  R.S.,  F.C.P.S.,  F.R.S.Ed., 
&c.,  Lucasian  Professor  of  Mathematics  in  the 
University  of  Cambridge,  LensJUld  Cottage,  Cam- 
bridge. 

Wheatstone,  Sir  Charles,  F.R.S.,  LL.D.,  K.L,H.,&c. 
19,  Park-Crescent,  Regents-park,  London^  W. 

Wurtz,  Adolph  Charles,  For.  Mem.  R.S.  Rua  St. 
Ouillaume,  27,  Paris, 

(2  Vacancies.) 


Honorary  Meniberi, 


25 


8ECTI0V  07  POLITE  LITEBATVBE  ft  AHTiaUlTlEB. 

[limited  to  30  Members,  of  whom  one-half  at  least  mui^t  be  foreigners.] 
Elected  in  the  Department  of  Polite  Literature, 


Date  of  Election. 


1863. 
1869. 
1869. 
1849. 
1869. 
1866. 
1863. 
1850. 


1869. 
1848. 
1863. 
1867. 
1863. 
1869. 


1854. 
1866. 
1841. 


1867. 
1867. 


Mar.  16 
Mar.  16 
Mar.  16 
Nov.  80 
Mar.  16 
Mar.  16 
Mar.  16 
Nov.  30 


Ebel,  Hermann.     Leipsic. 

Gayangos  y  Arce,  Don  Fascual  de.     London, 

Lassen,  Christian,  Ph.D.    Bonn, 

Lepsias,  Karl  Eichard.     Berlin, 

Mommsen,  Dr.  Theodore.     Berlin, 

Motley,  John  Lothrop,  Esq.,  D.C.L.   U,3,f  America. 

Miiller,  Professor  Max.     Oxford, 

Thiers,  Louis  Adolphe.     Paris, 


Elected  in  the  Department  of  Antiguiiies, 


Mar.  16 
Nov.  30 
Mar.  16 
Mar.  16 
Mar.  16 
Mar.  16 


Mar.  16 
Mar.  16 
Mar.  16 


Mar. 
Mar. 


Benavides,  Don  Antonio.    Madrid, 

Botta,  Paul  Emile.     Paris, 

Cochet,  L*Abb(5  Jean  Benoit  D^sir^.    Rouen, 

De  Eossi,  Commendatore  Giovanni  Battista.    Rome. 

Keller,  Ferdinand.     Zurich, 

*Larcom,  Eight  Hon.  Sir  Thomas  A.,  Bart,  Major- 
General,  KC.B.,  F.E.S.,  &c.  Heathfleld,  Fare- 
ham,  Hants, 

Mauray,  Alfred.     Paris, 

Nillssen,  Eev.  S.     Copenhagen, 

Phillipps,  {late  Halliwell,)  James  Orchard,  Esq., 
F.E.S.,  F.S.A.  Lond.  and  Edin.,  &c.  11, 
Tregunter-road,  South  Kensington,  London,  S,  W. 

Visconti,  Barone  Commendatore  P.  E.     Rome, 

Worsaae,  Prof.  Hans  Jacob  Asmussen.  Copenhagen, 


Elected  since  the  union  of  the  two  classes  of  Honorary  Members  in  this 

Section, 


1875.  Mar.  16 
1875.  Mar.  16 

1873.  Mar.  15 

1873.  Mar.  15 

1875.  Mar.  16 
1875.  Mar.  16 
1873.  Mar.  15 
1875.  Mar.  16 


Franks,  Augiistus  Wollaston,  M.A.,  F.RS.,  F.S.A. 

103,  Victoria-street,  London,  3,  W, 
Hardy,  Sir  Thomas  Duffus,  D.C.L.,  Deputy-Keeper 

of  the  Public  Eecords,  England.     35 ,  North-Bank, 

RegenfS'Park,  London,  N,W, 
Longfellow,  Henry  Wadsworth.     Cambridge,  Mass,, 

U,  S,,  America, 
Nigra,  BUs  Excellency  Cavaliere  Constantino,  Italian 

Minister  to  France*    Paris. 
Pictet,  Adolphe.     Geneva, 
Stuart,  John,  LL.D.,  F.S.A.  Scot.     Edinburgh. 
Westwood,  John  Obadiah,  Esq.,  F.S.A.     Oxford, 
Whitney,  William  Dwight.       Yale  College,  Con- 

necticut,  U,S,f  America, 

(3  Vacancies,) 


SUMMARY. 

••• 
••• 

••• 

••• 

life  Members           ••• 
Annnftl  Members 

Honorary  Members  (4  +  55)  ... 

Total, 

197 
174 

371 
59 

430 

Should  any  errors  or  omissionfl  be  found  in  this  list,  which  is  revised  to  Ist 
of  September,  1875,  it  is  requested  that  notice  thereof  may  be  given  to  the  Secre- 
tary of  the  Academy.     He  should  also  be  informed  of  the  death  of  any  Member. 

As  this  list  will  be  kept  standing  in  type,  it  can  be  readily  corrected  from  time  to 
time. 


R.  D.  Webb  and  Son.  Printers,  74,  Middle  Abbey-street,  Dublin. 


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