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Photographic 

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Couverture  de  couleur 


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T 
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L'Institut  a  rnicrofi'mi  le  meilleur  exemplaire 
qu'il  lui  a  6ti  possible  de  se  procurer.  Les  details 
de  cet  exemplaire  qui  sont  peut-Atre  uniques  du 
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modification  dans  la  mithoda  normaie  de  filmage 
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D 


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rrja    Showthrough/ 

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I      I    Includes  supplementary  material/ 


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obtenir  la  meilleure  image  possible. 


This  item  is  filmed  at  the  reduction  ratio  checked  below/ 

Ce  document  est  filmA  au  taux  de  rMuction  indiqu*  ci-dessous. 

10X  14X  18X  22X 


12X 


1SX 


20X 


26X 


30X 


y 


24X 


28X 


■w 


Th«  copy  filmed  h«r«  has  b««n  raproduead  thankt 
to  tha  ganarosity  of: 

Metropolitan  Toronto  Library 
Science  &  Technology  Department 

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possibia  considaring  tha  condition  and  lagiblllty 
of  tha  original  copy  and  In  kaaping  with  tha 
filming  contract  spacif Icationa. 


Original  coplaa  in  printad  papar  covara  ara  filmad 
beginning  with  tha  front  eovar  and  anding  on 
tha  last  paga  with  a  printad  or  lllustratad  impraa- 
sion.  or  tha  bacic  covar  whan  appropriata.  Ail 
othar  original  copiaa  ara  filmad  beginning  on  tha 
first  paga  with  a  printad  or  lllustratad  impraa- 
sion,  and  anding  on  tha  laat  paga  with  a  printad 
or  illuatratad  impraaaion. 


Tha  last  racordad  frama  on  aach  microfiche 
shall  contain  tha  symbol  ^»>  (meaning  "CON- 
TINUED"), or  tha  symbol  y  (meaning  "END"), 
whichever  applies. 

Maps,  plates,  charts,  etc..  may  be  filmed  at 
different  reduction  ratios.  Those  too  large  to  be 
entirely  included  in  one  exposure  are  filmed 
beginning  in  the  upper  left  hand  corner,  left  to 
right  and  top  to  bottom,  as  many  frames  as 
required.  The  following  diagrams  illustrate  the 
method: 


L'exemplaira  film*  fut  reproduit  grice  A  la 
gAnArosit*  de: 

IMetropolitan  Toronto  Library 
Science  &  Technology  DepartnMnt 

Les  imeges  suivantes  ont  At*  reproduites  avec  la 
plus  grand  soin.  compta  tenu  de  la  condition  et 
de  le  nettet*  de  I'exemplaire  film*,  et  en 
conformitA  avec  les  conditions  du  contrat  da 
filmage. 

Lea  exempleires  originoux  dont  la  couvarture  on 
papier  est  imprimie  sent  fiimAs  en  commen^ant 
per  le  premier  plat  et  en  terminant  soit  par  la 
darnlAre  page  qui  comporte  une  empreinte 
d'inr.  nression  ou  d'illustration.  soit  par  la  second 
plat,  salon  le  cas.  Tous  las  autres  exempleires 
originaux  sont  fiimis  en  commenpent  par  la 
pramlAre  paga  qui  comporte  une  empreinte 
d'impression  ou  d'illustration  at  en  terminant  par 
la  darniire  page  qui  comporte  une  telle 
empreinte. 

Un  dee  symboles  suivants  apparattra  sur  la 
darnlAre  imafie  de  cheque  microfiche,  selon  le 
cas:  le  symbole  -*•  signifie  "A  SUiVRE",  le 
symbols  V  signifie  "FIN". 

Les  cartes,  planches,  tableaux,  etc..  peuvent  Atre 
filmAs  A  des  taux  de  rAduction  diffArents. 
Lorsque  le  document  est  trop  grand  pour  Atre 
reproduit  en  un  seul  clichA.  il  est  fiimA  A  partir 
de  I'angle  supArieur  gauche,  de  gauche  A  droite. 
et  de  haut  an  bas.  en  prenant  le  nombre 
d'images  nAcessaire.  Las  diagrammes  suivants 
illustrent  la  mAthode. 


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2 

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4 

5 

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PUBLICATIONS 


FROM     I  UK 


BIOLOGICAL    LABORATORY 


(IF    TFIK 


UNIVERSITY    OF    TORONTO. 


No.  III.       STUDIES   ON   THE   BLOOD  OF  AMPHIBIA. 
By  A.    B.   MACALLUM,    M.B.,    Ph.D. 


(Reprinted  from  the  Transactions  of  the  Canadian  Institute,  Vol.  It..  Pt.  S.) 


TORONTC*: 

ThK    Corp,     C'LAKK     COMPANV,     LlMlTBD,     PrIKTKR.S. 

-         .  1892. 


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[Exlnict  Jrom  Transactions  of  the  Cancutian  Institute,  l,SH()!lJ.\ 


STUDIES  ON  THE  BLOOD  OF  AMPHIBIA. 

By  a.  B.  Macallum,  M.B.,  Ph.D. 

Lecturer  on  Physiology,  University  of  Toronto. 

(Read  lyth  January,  i8gi.) 
CONTENTS. 

Section   i.  The  Origin  of  Haemoglobin. 

a.  Methods  of  Study. 

b.  Structure  of  the  Blood  Corpuscles. 

c.  The  Origin  of  the  Haemoglobin  in  the  Red  Discs. 
Section  2.  The  Fu.siform  Corpuscles. 

Section  3.  The  Origin  of  the  Ha^matoblasts. 
Section  4.  Conclusions. 
Section  5.  Appendix. 


ill 


I.    The  Origin  of  H/Emoglobin.* 

In  the  following  pages  are  given  the  results  of  studies  commenced 
five  years  ago  and  continued  with  short  intermissions  till  last  summer. 
The  length  of  time  taken  up  in  this  work  was  necessarily  great  because  of 
the  lack  of  previous  studies  in  the  same  line  and  because  of  the  want  of 
definite  and  exact  knowledge  on  the  .subject  of  the  micro-chemical 
reactions  of  haemoglobin.  The  difficulty  of  detecting,  by  chemical  or 
microscopical  methods,  any  antecedents  of  haemoglobin  appeared  so 
formidable  that,  at  one  time  early  in  the  work,  I  was  on  the  point  of 
abandoning  the  line  of  investigation  altogether. 

I  have  used  for  this  investigation  our  Lake  Lizard,  Necturus  lateralis, 
and  the  larvae  of  Amblystoma  punctatum  which  are  readily  obtainable  in 
large  numbers  in  the  immediate  neighborhood  of  Toronto  in  April  and 
May.  The  advantages  which  the  tissues  and  structures  in  the  Necturus 
present  for  cytological  work  far  outweigh  those  which  a  comparative 
study  of  the  blood  in  a  larger  number  of  Amphibian  forms  would  have 
and  there  is,  therefore,  a  justification  for  narrowing  the  investigation  to 
the  two  named  forms. 


*  The  subject   matter  of  this   paper   was   included   in  a  thesis   presented   for  the  degree  of 
Doctor  of  Philosophy  in  the  Johns  lIopl<ins  University,  in  April,  1888, 


I*! 


46 


TRANSACTIONS   OP   TUB   CANADIAN    IN8TITIITR. 
A.     METHODS   OF   STUDY. 


[Vol.  II. 


At  the  outset  of  an  investif^ation  like  this,  one  has  to  answer  the 
question :  How  far  can  we  rely  on  the  different  effects  in  staining 
pr  jduced  by  a  dye  in  determining  the  dissimilarity  in  composition  of  the 
obj'icts  stained  ?  We  can  illustrate  the  question  by  a  case  in  point : 
safr.  nin  stains  the  nuclei  of  the  red  blood  cells  of  Necttirus  orange-red 
when  they  are  fixed  in  a  certain  way,  while  the  nuclei  of  ordinary  cells 
under  ';he  same  conditions  take  a  red  color.  Does  this  indicate  that  the 
substance  in  the  nuclei  of  the  red  corpuscles  which  is  stained  orange-red 
is  differiMit  in  its  chemical  composition  from  that  in  ordinary  nuclei .' 
An  affirr.iative  and  a  negative  answer  are  equally  consistent  with  what 
we  know  .is  yet  of  the  relation  between  staining  reagent  and  object  stained. 
It  is  quite  possible  to  imagine  the  molecules  of  the  staining  reagent  in 
the  object  stained  so  placed  relatively  to  the  molecules  of  the  latter  that 
though  no  chemical  union  results,  certain  kinds  of  the  light  rays  become 
absorbed  in  their  passage  through  the  object.  It  is  further  possible  to 
conceive  th;  t  variation  of  the  distance  of  the  molecules  from  each  other 
in  the  object  stained  may  result  in  a  variation  of  the  rays  transmitted. 
.Staining  is  n  this  sense  a  result  of  a  physical  condition,  and  as  such 
many  consider  it.  It  is  easy  also  to  understand  that  if  the  molecules  of 
one  stained  object  should  be  different  in  structure  from  those  of  another, 
the  interarra  igement  of  these  with  those  of  the  same  staining  reagent 
might  .affect  the  light  transmitted  in  each  of  the  two  cases  differently. 
In  such  the  difference  in  color  would  depend  on  a  difference  in 
chemical  composition  while  the  stain  in  itself  would  be  referable  to  a 
physical  condition.  In  addition  to  these  three  possible  modes  in  the 
production  of  staining  reactions  there  are  two  others,  viz.,  the  action  of 
the  stained  material  in  bringing  about  a  change  in  the  composition  of 
the  staining  reagent  and  the  definite  chemical  combination  of  the  staining 
and  stained  material.  The  action  of  the  stained  object  on  the  staining 
reagent  is  illustrated  by  the  effect  produced  by  the  chromatin  of  the 
hsmatoblasts  in  the  Amblystoma  larva;  on  alum  haematoxylin,  the 
usual  color  given  by  the  latter  reagent  to  ordinary  nuclear  constituents 
being  there  turned  to  a  slate  tint.  That  chemical  combination  does 
occur  in  the  case  of  some  reagents  is  shown  by  Unna's  experiments  with 
several  aniline  dyes.* 

There  being,  thus,  probably  several  ways  by  which  a  stain  in  an  object 
could  be  effected,  it  is  manifestly  impossible  to  prove  in  regard  to  any 
particular  dye,  whether,  when  it  stains  a  .series  of  objects,  the  same 
resulting  colors  in  the  latter  are   produced  by  the  same  or  different 

•Arch,  fur  Mikr.  Anat.,  Bd.  XXX.  p.  38. 


1890-91.  J 


AMPHIBIA   BLOOD   STUDIES. 


interaction,  pliysical  or  chemical,  of  dye  and  object.  It  is  of  course  not 
even  probable  that  the  chromatin  elements  of  all  cells  are  chemically  the 
same  except  in  the  main  outlines  of  their  structural  formul;e,  yet  aluin- 
h.-ematoxylin  or  alum-cochincal  gives  usually  the  same  color  re.iction  in 
all  Here  the  efifcct  is  the  same  but  the  interaction  may  or  may  not  be 
the  same  in  all  cases.  The  subject  belongs  to  borderland  between 
physics  and  chemistry  and  we  can  conceive  that  the  interaction  may  lie 
on  one  side  or  the  other  of  any  arbitrary  line  drawn  to  separate  the  two 
domains  without  resulting  in  any  visible  difference  in  color.  If  different 
colors  should  result  when  chromatin  elements,  for  example,  are  stained 
by  a  dye,  then  it  may  be  safely  inferred  that  the  groups  of  atoms  in  the 
variously  stained  elements  are  differently  related  to  the  groups  of  atoms 
in  the  staining  reagent.  It  might  be  suspected  in  such  a  case  that  the 
difference  in  stain  might  depend  on  a  difference  in  chemical  composition 
and  this  suspicion  would  become  certainty,  if  a  second  dye  were  found 
to  act  in  a  similar  way  towards  the  same  chromatin  elements. 

The  difficulties  which  surround  the  solution  of  questions  of  this  sort 
are  very  numerous  but  they  are  multiplied  when  one  multiplies  the 
methods  of  hardening  or  fixing  tissues.  These  methods  greatly  vary 
the  effects  of  a  single  staining  reagent  on  cellular  structures.  On  this 
account  no  conclusion  of  any  great  value  has  been  drawn  as  to  chemical 
nature  of  any  cellular  substance  from  the  employment  of  staining 
reagents  alone.  On  the  other  hand  the  employment  in  cytological 
research  of  chemical  reagents  on  objects  under  the  microscope  has  not 
been,  even  to  a  limited  extent,  successful. 

I  have  put  forward  all  the  difficulties  which  a  research  like  this 
presents  and  they  have  all  through  this  work  been  before  my  mind. 
I  have  resorted  to  the  processes  of  staining,  because  the  question 
of  the  origin  of  haemoglobin  is  an  all  important  one  and  because 
I  can  see  no  other  means  of  settling  it.  It  may  be  said  that  the 
means  are  insufficient.  I  can  only  say  in  answer  that  I  have  tried 
to  do  the  best  with  them  and  the  conclusions  given  in  this  paper  are 
drawn  from  the  results  obtained  by  the  employment  not  of  a  few  but  of 
a  very  large  number  of  methods  of  hardening  and  staining.  It  is  only  by 
the  employment  of  various  staining  reagents  that  one  can  avoid  the 
errors  resulting  from  an  adherence  to  one  or  to  a  few  microscopical 
methods  and  at  the  same  time  reach,  usually,  at  least,  measureably 
certain  conclusions. 

My  first  labors  in  this  investigation  were  directed  to  finding  a  reagent 
which  would  show  the  presence   not  only  of  h.-emoglobin,  but  of  its 


48 


TRANSACTIONS    OF   TIIK   CANADIAN    INSTITUTB. 


[Vol.  II. 


antecedent  if  such  existed.  I  need  hardly  go  over  the  list  of  wearisome 
experiments  which  I  made  for  this  purpose.  Many,  but  not  all,  of  these 
were  resultless.  Of  the  dyes  at  my  disposal  belonging  to  the  aromatic 
group  of  organic  compounds,  Eosin  is  the  only  one  which  I  found  useful. 
As  will  be  shown  below  it  reacts  with  haemoglobin  and,  in  conjunction 
with  alum-ha.'nr,atoxylin  or  alum-cochineal,  it  is  a  reagent  for  the 
antecedent  of  the  pigment.  Taken  of  course  alone,  without  employing 
any  other  reagent  for  control  purposes,  it  gives  results  far  from  satisfactory 
and  it  is  also  very  misleading.  Another  reagent,  the  employment  of 
which  has  been  of  great  value  to  me,  is  the  .staining  fluid  of  Shakespeare 
and  Norris,*  and  which  I  shall  name  throughout  this  paper,  for  the  sake  of 
brevity,  the  Indigo-carmine  Mixture  or  Fluid. 

This  fluid  is  made  according  to  a  formula  which  I  have  modiflcd  from 
that  given  by  Bayerl,  and  consists  of  a  mixture  of  equal  volumes  of  the 
following  solutions  : — 

A — Carmine,  2  grms ;  Borax,  8  grms  ;  Distilled  Water,  lOO  c.c. 
B. — Sulphindigotate  of  Soda  (Indigo-carmine),  8  grams  ;  Borax, 
8  grms  ;  Distilled  Water,  lOO  c.c. 

In  preparing  each  of  these  solutions,  the  borax  is  ground  up  in  a  mortar 
with  the  dye,  the  water  poured  on,  and  the  whole  allowed  to  stand  for 
from  five  to  seven  hours  before  filtering.  Owing  to  the  fact  that  much  of 
the  Indigo-carmine  in  the  market  is  impure,  and  consequently  alters  its 
composition  in  solution  in  a  couple  of  weeks,  it  is  not  advisable  to  prepare 
more  than  25 — 50  cc.  of  solution  B  at  a  time.  I  have  obtained 
quantities  of  the  reagent  which  retained  in  solution  for  three  months  its 
normal  staining  properties.  As  A,  when  kept  for  a  year  or  more,  readily 
shows  undiminished  staining  power,  a  larger  quantity  may  be  prepared 
:  as  "  stock  "  solution. 

The  section  to  be  stained  is  left  in  the  fluid  for  fifteen  minutes,  then 
plunged  in  a  saturated  solution  of  oxalic  acid  for  ten  minutes,  washed  in 
distilled  water,  dehydrated  with  absolute  alcohol,  cleared  in  pure  xylol, 
and  mounted  in  benzol  balsam.  Preparations  made  in  this  way  two 
years  ago  still  retain  undiminished  their  original  stain.  When  I  first 
employed  the  fluid,  four  years  ago,  I  used  clove-oil  for  clearing,  and 
found  that  my  preparations  faded,  or  contained  a  dirty  precipitate  after 
three  or  four  weeks.     The  removal  of  the  clove-oil  after  clearing  with 

*  I  have  not  seen  the  paper  of  Shakespeare  and  Norris  describing  the  stain  or  its  properties 
and  capacities  and  my  attention  was  first  directed  to  it  by  Bayerl's  work  on  the  formation  of 
blood  corpuscles  on  the  margins  of  ossifying  zones  in  bones  :   Arc/i.  fur  Mikr.  Ana/.     Bd 
XXIIl.  p.  30. 


1890-91.] 


AMPHIBIA    BLOOn    STUOIKS. 


49 


xylol,  postponed,  but  did  not  prevent,  fadintj.  It  seems  that  the  essential 
oils,  even  in  small  quantities,  possess  an  oxidising;  power  to  which  the 
sulphindigotatc  of  soda  is  subject. 

In  order  to  get  the  best  effects  with  this  stain,  the  tissues  arc  to  be  hard- 
ened with  reagents  which  preserve  the  hiemoL^lobin  and  its  norinal  dis- 
tribution in  the  corpuscles.  Some  of  the  ordinary  hardening  reagents  do 
not  fix  haemoglobin  (Midler's  Fluid  and  solutions  of  potassic  bichromate), 
others  decompose  it  (weak  solutions  of  chromic  acid),  while  others  again 
cause  the  hajmoglobin  and  the  so-called  stroma  containing  it  to  shrink 
irregularly  in  the  corpuscles.  The  very  fact  that  a  reagent  removes  or 
decomposes  the  haemoglobin  does  not  prevent  its  employment  in  the 
stutiy  of  the  mode  of  formation  of  the  pigment,  but  points  to  its  useful- 
ness in  testing  and  controlling  the  results  obtained  by  reagents  which  fix 
the  haemoglobin  well.  For  instance,  I  have  used  chromic  acid  for  the 
purpose  of  removing  the  haemoglobin  and  fixing  the  antecedent.  Even 
in  the  list  given  below  the  haemoglobin-fixing  prc<pcrty  is  not  the  same 
in  all,  and  again  the  reagent  which  fixes  the  h;emoglobin  in  the  red 
corpuscles  in  pieces  of  the  spleen  niay  not  have  the  same  property  as 
regards  cover-glass  preparations  of  the  blood.  These  facts  should  be 
borne  in  mind  in  every  research  on  red  blood  corpuscles.  The  method 
which  I  adopted  after  a  long  series  of  experiments  was  as  follows  : — 

Small  portions  of  the  spleen  of  iV^f/«rwj  were  allowed  to  lie  half-an- 
hour  in  a  saturated  solution  of  corrosive  sublimate,  or  five  days  in 
Erlicki's  Fluid,  or  twenty-four  hours  in  a  \ — ,?,%  solution  of  chromic 
acid,  five  hours  in  a  saturated  solution  of  picric  acid  or  two  to  five  hours 
in  I  %  solution  of  osmic  acid.  They  were  afterwards  washed  in  distilled 
water  and  put  in  alcohol  of  50%  strength  for  two  hours  and  then  in  70% 
for  twenty-four  hours  and  finally  in  95%.  The  70%  alcohol  was  changed 
several  times,  each  at  an  interval  of  twenty-four  hours  in  the  case  of  the 
chromic  and  picric  preparations.  The  pieces  were  imbedded,  either  in 
mucilage  and  sectioned  on  the  freezing  microtome,  or  by  the  chloroform 
method  in  paraffin  by  which  sections  of  about  5 — lO/^  were  made.  The 
latter  were  freed  from  paraffin  with  turpentine  and  passed  through 
absolute  alcohol  to  water  in  the  usual  way.  These,  as  well  as  those 
prepared  with  the  freezing  microtoine.  were  transferred  to  the  Indigo- 
carmine  Fluid  and  treated  in  the  manner  described  above. 

The  f^reat  value  of  these  preparations  consists  in  the  fact  that  h.-emo- 
globin  is  stained  grass-green  or  greenish-blue  while  other  proteid  elements 
are  colored  red.  This  grass-green  or  greenish-blue  is  shown  by  a  few 
other  elements,  but  thiese  are  so  well  known  and  so  easily  recognised  that 
no  confusion  can  result.    The  numberof  structures  other  than  haematogenic 


flO 


TRANHAmONH   OF    TUB   OANADIAN    INHTITI  TE. 


[Vol.  11. 


I 


to  which  the  Indif^o-ciirmine  Fluid  pivcs  ,i  tjrass  green  color  are  so  few 
that  thoy  may  be  mentioned  here  :  the  yolk  spherules,  the  degcueratin^j. 
peripherally  arranged, nucleolar  bodies  in  the  nuclei  of  maturing  amphibian 
ova,  the  nuclei  (.f  some  of  the  clavate  cells  in  the  skin  of  Necturus,  als(j 
some  of  the  nuclei  of  some  of  the  ci'taneous  mucous  glands  of  the  same 
(in  chromic  aciil  ureparations),  the  nuclear  and  cellular  elements  in  the 
stratum  granulosum  and  stratum  lucidum  of  the  epidermis,  structures  in 
the  sheaths  and  cellular  layers  of  hair  follicles,  yolk-lik  -.  elements  in  the 
protoplasmic  layer  (syncytium)  covering  the  chorionic  villi  in  the  cat, 
the  substance  of  the  dim  band  in  striated  muscle  fibre,  and  finally, 
though  not  so  distinctly,  the  lardacei  •.  of  amyloid  degeneration.  It  will 
be  seen  from  this  list  that  except  in  the  Amblystoma  larvJE  in  which 
there  is  abundance  of  yolk  spherules,  there  is  no  danger  of  mistaking  any 
other  compound  for  h.cmoglobin.  Where  such  a  mistake  was  possi- 
ble as  in  the  case  of  the  larvai,  I  resorted  to  other  staining  reagents. 
From  the  list  given  it  is  to  be  inferred  that  the  Indigo-carmine  Fluid  is  a 
valuable  reagent  for  certain  processes  of  cellular  degeneration.  In 
connection  with  striated  muscle  fibre  the  reaction  is  significant,  pointing 
to  the  derivation  in  the  Amblystoma  larvas,  of  a  portion  at  least  of  the 
dim  band  from  the  yolk  spherules  (the  hsmatogen  of  Bunge?)  or  demon- 
strating in  the  dim  bands  in  Necturus  the  presence  of  the  red  pigment 
described  as  haemoglobin  (KUhne,  Ray-Lankester,  Levy  and  Hoppe- 
Seyler)  or  as  myoh,Tematin  (MacMunn). 

I  stated  that  the  reaction  of  the  Indigo-carmine  Fluid  with  haemoglobin 
results  in  a  grass-green  or  a  greenish-blue  color,  but,  strictly  speaking,  the 
greenish-blue  color  or  stain  should  appear  only  when  the  haemoglobin 
has  been  fixed  with  corrosive  sublimate.  I  omitted  to  state,  moreover, 
that  the  antecedent  of  haemoglobin  gives  under  certain  conditions  the 
grass  green  color  with  the  staining  reagent. 

Bayerl*  endeavoured  in  the  following  way  to  prove  that  the  substance 
in  the  red  corpuscles  staining  grass  green  with  the  Indigo-carmine  Fluid 
is  haemoglobin  :  A  quantity  of  dried  amorphous  haemoglobin  from  dog's 
blood  was  dissolved  in  water,  mixed  with  the  indigo-carmine  Fluid  and 
the  mixture  treated  with  a  saturated  solution  of  oxalic  acid.  The  color 
of  the  whole  was  grass-green.  This  experiment  is  not  so  decisive  as  it 
appears  from  the  description,  for  I  found  that  it  is  only  once  in  a  while  that 
a  green  shade  appears  in  the  mixture.  I  found  also  on  spectroscopic 
examination  of  the  mixture,  that  the  haemoglobin  was  on  the  addition 
of  oxalic  acid  more  or  less  rapidly  transformed  into  hsematin.      Even 


*  Loc  cit. 


1890-yi.] 


AMPHIIIU    IlLOOI)    HTUDIKH. 


Al 


few 

"If,', 
lian 
il.so 
nil." 
the 
in 
the 
cat, 


when  a  quantity  of  solution  H.  (sec  p.  224)  alone  was  mixed  with  a  pure 
solution  of  ha-mofjlobin  and  the  mixture  treated  with  a  saturated 
solution  of  oxalic  acid  there  resulted  only  a  dirty  brownish  precipitate 
from  the  decomposed  hiL-mo^'lobin.  This  proves  that  soluble  hieino- 
globin  cannot  yield  any  reliable  reactions  with  the  Indigo-carmini.  l-'luid. 
Acting  on  the  view  that  the  h.x'.no^lobin  in  my  preparation  is  a 
fixed  insoluble  compound  and  therefore  quite  different  from  that  obtained 
for  example,  by  niere  crystallization  from  dog's  blood,  I  modified  Bayerl's 
experiment.  I  took  pure  crystallized  h;emo^dobin  from  do^'s  blood, 
dissolved  it  in  distilled  water  and  mixed  it  with  an  equal  volume  of 
ajjar-agar  solution*  made  liquid  at  42X.  Stirred  rapidly  and  then 
cooled  by  plunging  the  base  of  the  containing  Vv'^ssel  in  pounded  ice,  th.i 
deep  red  agar-agar  mixturr  'incomes  firm  enough  to  cut  with  a  knife. 
I  made  pieces  about  one-eighth  of  an  inch  in  thickness  which  I  put  in 
various  hardening  fluids,  as  in  the  case  of  the  spleen  of  the  Nectiirus. 
When  the  fixation  was  complete  the  excess  of  the  reagent  was  removed 
with  alcohols  50%,  70%  and  00%  successively,  sections  of  the  pieces 
were  made  on  the  freezinfj  microtome  and  stained  with  the  Indigo- 
carmine  Fluid.  The  preparations  made  with  chromic  acid  or  Erlicki's 
Fluid  gave  a  grass-green  reaction  while  those  made  with  corrosive 
sublimate  gave  a  greenish  blue,  practically  the  same  results  as  in 
the  case  of  the  hjemoglobin  in  the  red  corpuscles.  The  fact  that  the  cor- 
rosive sublimate  preparations  gave  a  greenish  blue  color  with  the  Indigo- 
carmine  Fluid,  while  the  other  preparations  gave  a  grass-green,  would 
lead  one  to  suspect  that  there  might  be  a  difference  in  the  chemica[ 
composition  of  the  reagent  when  absorbed  in  the  two  kinds  of  pre- 
paration.s.  If  there  is  such  a  difference,  it  cannot  be  in  the  indigo 
portion  of  the  staining  molecule,  for  blue  and  grass  green  sections  with 
the  spectroscope,  give  alike  the  indigo  absorption  bands  and  no  more. 

I  used  also  in  staining  sections  of  the  spleen  alum-hsmatoxylin 
solutions,  in  which  ammonia  alum  is  dissolved  to  saturation,  and  Czokor's 
alum-cochineal.  These  two  reagents  are  of  great  value,  especially  the 
former,  in  connection  with  the  studies  on  the  hasmatoblasts  in  the  Anibly- 
stoma  larvse,  the  latter  having  been  in  various  stages  of  their  d  velopment 
fixed  in  chromic  acid  (/^°/o).  Flemming's  Fluid,  corrosive  sublimate,  and 
Erlicki's  Fluid.  Though  the  other  reagents  have  their  uses,  the  second 
and  third  mentioned  were  the  only  ones  to  give  good  general  results. 
My  preference  is  decidedly  for  Flemming's  Fluid  for  larval  or  emb.'yonic 
tissues.     Half  an  hour  is  long  enough  for  ihis  reagent  to  act,  since  with 


•Of  the  strength  and  characters  recommended  by  Biondi.     Arch,  fur  Mikr.  Anat.     \'A. 
XXXI.,  p.  105. 


52 


TUANSACTIONS   OF   THE   CANADIAN    INSTITUTE. 


[Vol,.  :i. 


a  longer  stay  in  it  the  yolk-spherules  blacken  and  the  chromatin  elements 
in  the  nuclei  are  stainable  with  more  difficulty  in  alum-hcematoxylin. 
Alter  the  employment  of  any  of  the  hardening  reagents  the  larva;  were 
washed  for  a  couple  of  minutes  in  distilled  water,  for  ten  minutes  in  SO^/o 
alcohol,  then  in  7o*/o  alcohol,  until  all  traces  of  the  hardening  reagent 
were  removed,  when  they  were  put  into  and  kept  in  95 "/^  alcohol.  The 
larvae  were,  as  a  rule,  and  more  advantageously,  stained  in  toto  in  alum- 
h.-ematoxylin  or  alum-cochineal.  When  the  sections,  obtained  after 
imbedding  by  the  chloroform-paraffin  method,  were  fixed  on  the  slide 
with  clove  oil-collodion,  a  second  stain,  eosin,  was,  when  desired, 
employed.  I  used,  also,  the  triple  and  quadruple  stains  of  Gaule  for 
the  larvae  as  well  as  for  sections  of  the  sr'  "vn.  in  Necturus,  but  I  cannot 
say  that  I  have  derived  any  advantage  fi        them. 

Cover-glass  preparations  were  made  of  the  blood  of  the  larvae  and  of 
Necturus.  These  were  fixed  either  in  the  fumes  of  osinic  acid  (l% 
solution  for  two  hours),  or  by  a  saturated  solution  of  corrosive  sublimate, 
or  picric  acid,  or  by  Erlicki's  Fluid.  These  were  the  only  reagents  which 
I  found  serviceable.  The  method  of  opera^^ing  was  to  decapitate  the 
living  specimen,  to  allow  a  small  drop  of  the  blood  to  fall  on  the  cover- 
gla-^s  on  which  it  was  evenly  spread,  then  to  submerge  the  cover  in 
corrosive  sublimate  solution  for  five  minutes,  in  picric  solution  for  five 
hours,  or  in  Erlicki's  fluid  for  two  days.  When  osmic  acid  was  used  the 
cover  was  put,  with  the  preparation  surface  downward,  on  the  mouth  of 
the  unstoppered  reagent  bottle  for  two  hours.  The  fixation  was  com- 
pleted as  usual  with  alcoho'  and  the  various  dyes  referred  to  above  were 
used  for  staining  the  preparations. 

Fresh  cover-glass  preparations  of  blood  were  also  extensively  studied 
both  before  and  after  the  addition  of  coloring  reagents,  such  as  acetic 
methyl-green,  acetic  methyl-violet,  picrocarmine,  &c. 


As  regards  the  optical  apparatus,  I  had  for  the  finer  work  the  yV  in. 
hom.  imm.  of  Leitz,  the  j'j  in.  hom.  imm.  (r43  N.  A.)  of  Powell  and 
Lealand,  the  yi  in.  hom.  imm.  and  the  L.  (water  imm.  ^-g  in.)  of  Zeiss. 
I  used  during  the  last  summer  the  3  mm.  apochromatic  of  the  last  named 
maker  when  studying  the  blood  of  the  larval  Amblystomata. 


B.    STRUCTURE  OF  THE  BLOOD  CORPU.SCLES   IN    NECTURUS. 


Th'j  fresh  y  drawn  blood  of  Necttirus  contains  the  usual  red  corpuscles 
of  known  foim,  leucocytes  and  the  so-called  fusiform  corpuscles.  The 
first  and  last  classes  of  elements  merit  a  detailed  description,   owing 


;l. 


1890-91.] 


AMPHIBIA    BLOOD   STUDIES. 


53 


of 


to  their  relation  to  each  other  and  to  the  importance  of  the  questions 
raised  in  these  studies. 

The  red  cells  measure  50 — 53/i  in  length  and  30 — 32/i  in  breadth.  In 
the  fresh  and  normal  condition  they  present  usually  in  nucleus  and 
disc  a  uniform  yellow  red  tint,  and  in  the  disc  a  completely  homo- 
geneous discoplasma.  There  are  sometimes  corpuscles  possessing 
\vhiti.sh  nuclei  which  appear  contrasted  in  this  respect  with  the  colored 
disc,  but  these  are  not  numerous  until  the  preparation  has  been  kept 
under  certain  conditions,  as  in  a  moist  stage,  for  some  time.  In  such 
nuclei  one  can  determine  the  presence  of  a  coarse  network.  The  mem- 
brane of  the  disc  is  very  thin,  so  much  so  that  when  it  is  ruptured  and 
freed  of  its  contents  it  is  rarely  visible.  I  have  frequently,  by  artificial 
means,  ruptured  a  large  number  of  the  discs  in  a  moist  chamber  and  in 
only  a  very  few  cases  was  I  able  to  see  the  resulting  free  membranes, 
although  there  were  in  such  preparations  an  abundance  of  free  nuclei. 
The  contents  of  the  ruptured  corpuscles  have  different  fates.  That  of 
the  nucleus  and  of  a  portion  of  the  protoplasm  I  shall  describe  fully 
when  treating  of  the  fusiform  corpuscle.  The  haemoglobin  and  the 
stroma  containing  it  become  dissolved  in  the  serum,  hardly  leaving  a 
trace  visible.  This  points  to  the  fluid  character  of  the  discoplasma  and 
I  now  proceed  to  prove  that  view  of  its  structure. 

If  a  cover-glass  preparation  of  the  blood  is  fixed  with  a  saturated  solu- 
tion of  corrosive  sublimate,  stained  with  ha^matoxylin  and  eosin,  mounted 
in  balsam  and  studied  with  the  best  objectives  at  one's  disposal,  the 
protoplasm  of  the  disc  will  appear  perfectly  homogeneous  and  will  be 
seen  stained  uniformly  and  fntensely  by  the  eosin.  Granules  and 
vacuoles  are  absent,  and  if  the  nuclear  membrane  is  shrunken  away  from 
the  discoplasma,  the  edge  of  the  latter  next  it  will  then  appear  regularly 
and  evenly  outlined.  Vapor  of  osmic  acid  fixes  the  discoplasma  in 
the  same  way  that  corrosive  sublimate  does.  This  brings  out  distinctly 
the  fact  that  there  can  be  no  natural  separation  of  stroma  and  haemoglo- 
bin in  the  discoplasma.  In  other  words,  v.'e  may  say  that  the  latter 
is  not  homologous  with  the  cytoplasma  and  enchylema  of  ordinary 
cells,  but  that  in  the  normal  condition  it  is  in  the  physiological  sense 
a  single  element.  It  is  true  that  in  certain  methods  of  fixation  the 
protoplasm  of  the  disc  appears  reticulated,  and  this  may  occur  in  a 
few  of  the  cells  fixed  by  corrosive  sublimate  (Fig.  i),  but  in  every  case 
the  fineness  and  arrangement  of  the  reticular  trabecular  depends  on 
the  method  of  fixation,  and  this  shows  that  the  reticulum  is  artificially 
produced.  One  has  but  to  look  at  Figs,  i,  2,  3,  and  4  to  see  how  the 
artificial  structure  varies  in  character.      The  preparation  of  the  blood 


!■ 


64 


TRANSACTIONS    OV    TUI::    CANADIAN    INSTITUTE. 


[Vol.  II. 


corpuscles  of  the  Amhlystoma  larvae  illustrates  this  variation  also  (Figs. 
5,  and  7),  the  corpuscles  treated  with  Flemming's  fluid  frequently 
presenting  a  coarse  network  ;  those  made  with  acetic  methyl-green 
showing  a  fine  one,  while  those'fixed  with  osmic  acid  showed  none  at  all. 

If  there  is  a  stroma  or  any  network,  it  does  not  separate  itself  from  the 
haemoglobin,  when  the  latter  crystallizes,  even  in  the  corpuscle.  I  have 
often  watclied  in  the  moist-stage  chamber  the  cr)'stallization  of  the  haemo- 
globin, especially  when  the  instrument  permits  a  slow  evaporation  of  the 
water  of  the  blood,  and  found  on  the  border  or  edge  of  the  drop  that  the 
ha-moglobin  contents  of  a  single  blood  corpuscle  crystallized  without 
exuding  from  or  passing  out  of  the  cell  membrane.  In  some  cases  the 
latter  was  seen  to  be  more  and  more  pushed  out  at  certain  points  until 
it  possessed  a  rhomboid  form  like  that  of  the  contained  crystal.  The 
membrane  became  invisible  when  evaporation  passed  a  certain  limit  owing 
no  doubt  to  the  greater  density  of  the  medium  (serum).  These  crystals 
are  usually  of  the  same  length  and  breadth  as  the  original  corpuscle  and 
they  contain,  moreover,  a  large  central  oval  space,  the  cavity  of  the 
nucleus.  Now  these  crystals  differ  in  size,  but  not  in  form,  from  those 
obtained  by  rupturing  the  corpuscles  and  slow  drying  of  the  blood.  In 
the  latter  the  crystals  are  very  long  and  narrow.  If  there  is  a  stroma 
why  does  it  not  interfere,  not  only  with  the  crystalline  form,  but  with 
the  power  of  crystallization  in  the  haemoglobin  ? 

The  nuclei  measure  20 — 2IA1  by  i2/x.  With  ordinary  powers  (Zeiss  D), 
they  appear  homogeneous,  less  deeply  shaded  than  the  disc,  the  haemoglo- 
bin tint  which  they  may  appear  to  have  being  merely  due  to  that  of  the 
superposed  portion  of  the  disc,  and  they  often  are  uncolored  or  whitish 
in  contrast  with  the  latter.  With  high  powers,  such  as  oil-immersion 
objectives,  one  can,  in  a  perfectly  normal  and  fresh  corpuscle,  determine 
the  existence  of  a  wide-meshed  network.  This  is  formed  sometimes  of 
thick,  sometimes  of  thin  trabeculae,  and  it  is  often  straw-yellow  in  color, 
in  other  word     it  apparently  contains  haemoglobin. 

I  now  lea  e  the  description  of  the  red  corpuscles  to  take  up  the 
question  of  the  origin  of  haemoglobin  in  them. 

C.      THE   ORIGIN   OF   THE   H.liMOGLOBIN    IN   THE   RED   DISCS. 

If  cover-glass  preparations  of  the  blood  oi  Necturus  or  portions  of  the 
spleen  of  the  same  animal  be  fixed  in  various  ways  it  will  be  found  that 
the  haemoglobin  of  the  red  cells  in  the  different  preparations  is  obtained 
in  various  degrees  of  preservation. 

One  of  the  most  convenient  fixative  reagents  for  haemoglobin  in  the 


ir. 


1890-91.] 


AMPHIBIA    BLOOD   STUDIES. 


65 


ntly 
een 
all. 


red  discs,  and  especially  when  employed  on  the  spleen,  is  Eriicki's  Flu'd. 
This,  combined  with  the  Indi<fo-carmine  Fluid  described  in  the  foregoing 
pages,  gives  a  remarkably  sure  means  by  which  one  can  determine  the 
presence  of  the  pigment.  The  red  cells  of  the  spleen  present  with  this 
fixative  reagent  and  the  staining  fluid  a  uniformly  gra.ss-grcen  disc 
in  which  no  structural  elements  can  be  observed  and  a  nucleus  which 
may  be  either  carmine  red  or  grass-green,  or  of  a  s^ide  in  green. 
Sometimes  the  nucleus  presents  a  network  as  deeply  grass-green  as  the 
substance  of  the  disc,  while  the  substance  in  the  meshes  of  the  net-work 
is  red.  These  different  effects  obtained  on  the  nuclear  structures  are 
not  due  to  artificial  or  physical  conditions  such  as  the  early  or  late 
action  of  the  fixative  reagent,  for  all  the  described  features  can  be  found 
in  the  nuclei  of  cells  placed  side  by  side.  Without  raising  the  question 
at  present  whether  there  is  any  haemoglobin  in  the  nucleus,  a  question 
which  might  be  prompted  by  an  observation  already  made  above,  it  may 
be  concluded  that  the  nuclei  of  the  red  cells  are  not  all  similar  in  their 
chemical  relations  towards  sulphindigotate  of  sodium  This  conclusion 
may  be  also  drawn  from  a  study  of  cover-glass  preparations  of  blood  in 
which  it  is  often  easy  to  see  a  grass-green  network  in  the  carmine-red 
nuclei  of  the  red  cells. 

In  cover-glass  preparations  fixed  with  osmic  acid  vapor  in  which  the 
layer  of  blood  is  very  thin,  the  haemoglobin  is  also  well  preserved. 
Here  the  nuclei  of  the  red  cells  have,  after  the  employment  of  Indigo- 
carmine  Fluid,  a  grass-green  network  in  the  meshes  of  which  the 
substance  is  faint  red.  In  similar  cover-glass  preparations  in  which  the 
layer  of  blood  is  comparatively  thick  the  discs  of  the  red  cells  are 
grass-green,  the  nuclei  distinctly  red  with  a  green  net-work.  In  cover 
preparations  on  which  the  solution  (i%),  instead  of  the  vapor  of  osmic 
acid,  was  used  the  same  staining  reagent  gave  red  nuclei  and  grass-green 
discs  to  the  red  cells. 

In  cover  preparations  of  the  blood  made  with  corrosive  sublimate 
solutions  the  Indigo-carmine  Fluid  stained  the  discs  and  nuclear  network 
deep  blue  green,  while  the  substance  in  the  meshes  of  the  net-work  is 
colored  from  a  light  to  a  deep  red,  oftener  the  former.  Frequently, 
with  an  ordinary  power  such  as  a  D  of  Zeiss,  very  many,  or  nearly  all 
nuclei  of  the  red  cells  appear  homogeneously  red,  but  with  the  employ- 
ment of  an  oil  immersion  (yV  in.)  the  presence  of  the  blue  green  network 
can  be  distinctly  determined. 

Flemming's  Fluid,  Miiller's  Fluid  and  chromic  acid  dissolve  the  haemo- 
globin out  of  the  red  discs  in  cover-glass  preparations  of  the  blood  and 


56 


TRANSACTIONS    OF    THE    CANADIAN    IN8TITUTB. 


[Vol.  II. 


i 


in  such  cases  it  is  difficult  or  even  impossible  to  get  any  reactions  at  all 
with  the  Indigo-carmine  Fluid. 

In  preparations  of  the  blood,  therefore,  made  with  corrosive  sublimate, 
osmic  vapor,  and  Erlicki's  Fluid,  and  subsequently  stained  with  the 
Indigo-carmine  Fluid,  the  nuclei  of  the  red  cells  are  shown  to  contain 
two  substances:  one  which  stains  grass-green  or  blue-green  ^-langed  as 
a  network,  the  other  colored  red  (light  or  deep),  situated  in  the  spaces 
formed  by  the  network. 

It  is  now  pertinent  to  ask  whether  the  nuclear  network  is  formed  of 
or  contains  ha;moglobin,  or  whether,  as  it  may  happen  to  be  chromatin, 
it,  as  such,  merely  shows  a  special  affinity  for  sodic  sulphindigotate, 
without  pointing  to  any  relationship  between  it  and  haemoglobin.  I 
have  already  stated  in  the  description  of  the  fresh  and  living  red  cell 
that  its  nucleus  frequently  presents,  under  oil-immersion  objectives,  a 
straw-yellow  network  which  is  seen  in  contrast  with  the  slight  pale- 
ness of  the  rest  of  the  nuclear  substance.  This  would  seem  to  indicate 
the  existence  of  haemoglobin  in  the  nuclear  network.  That  it  is  not 
hemoglobin,  though  a  substance  allied  to  it — ^judging  from  its  color 
in  the  fresh  cell  and  its  reactions  with  sodic  sulphindigotate  in  the 
fixed  cell — is  shown  by  the  employment  of  picric  acid  as  a  fixative 
reagent  on  cover  preparations  and  the  use  of  the  Indigo-carmine  Fluid. 
In  such  the  discs  of  the  red  cells  are  somewhat  vacuolated  but  they  are 
colored  grass-green  while  their  nuclei  are  either  light  red  with  a  deep  red 
network,  or,  sometimes,  light  blue  with  a  deep  red  network.  If  haemo- 
globin is  present  in  the  nucleus  it  ought  in  picric  acid  preparations  to  be 
as  readily  detectable  there  as  in  the  disc. 

The  question  now  advanced  is :  what  is  the  composition  of  the 
substance  forming  the  nuclear  network  and  of  that  filling  its  meshes? 

If  a  section  of  the  spleen  hat-Hened  in  chromic  acid  is  stained  with  the 
Indigo-carmine  Fluid,  the  dis..i  of  the  red  cells  appear  faint  red  while 
their  nuclei  are  colored  a  deep  grass-green.  In  the  latter  there  is  not 
the  slightest  trace  of  a  differentiation  into  network  and  mesh  substance. 
Evidently  then  the  employment  of  chromic  acid  has  converted  the  whole 
of  the  nuclear  substance  into  something  which  stains  grass-green  with 
the  Indigo-carmine  Fluid.  The  latter  reagent  is  not  the  only  one  which 
shows  this  conversion  for  alum-haematoxylin,  alum-cochineal  and  safranin 
stain  homogeneously  the  nuclei  of  the  red  cells  of  such  preparations. 
The  whole  of  the  nucleus,  both  network  and  mesh  substance,  must 
be  regarded  therefore,  as  modified  chromatin  or  as  a  mixture  of 
chromatin  and  achromatin,  the  latter  being  rendered  capable  by  the 
chromic  acid  of  absorbing  staining  matters.     That  we  have  nothing  to 


1890-91.] 


AMPHIBIA    BI.OOD   STUDIKS. 


57 


do  here  with  achromatic  substance  is  shown  in  sections  of  the  spleen 
hardened  with  Flemming's  fluid  and  stained  with  alum-haimatoxylin. 
In  such  preparations  the  nuclei  of  the  red  cells  take  a  homogeneous  deep 
stain  thus  proving  that  there  is  no  conversion  of  achromatin  into 
chromatin  or  into  a  substance  which  reacts  towards  dyes  like  the  latter. 
Hence  we  may  conclud  ■  that  the  nuclf^ar  contents  in  the  red  cells  are 
formed  of  chromatin  more  or  less  modified. 

If  the  nuclei  of  the   fully  formed   red  cells  in  a  larval  Amblystoma 
hardened  in  Flemming's  Fluid  be  put  under  observation,  a  condition  is 
seen  in  them  similar  to  that  found  in  the  nuclei  of  the  red  cells  of  the 
spleen  hardened  in  chromic  acid,  that  is,  they  stain  in  the  majority  of 
cases  with  alum-haimatoxylin,  alum-cochineal  in  the  same  way,  taking  a 
uniform  homogeneous  tint.     There  can  be  no  doubt  that  here  the  nuclei 
are  well  preserved.      In  some  larva;  again,  there  are  found  a  few  fully 
formed  corpuscles  in  which  the  nuclear  network  alone  is  stained.     There 
are  also  other  nuclei  in  such  larvae  which  present  different  amounts  of  a 
stainable  mesh  substance  and  the  inference  gained  from  the  study  of 
such   nuclei    is   that  the  stainable  mesh  substance   takes    its   origin  in 
the  network  and  as  the  latter  in  the  newly  formed  corpuscles  contains 
the  whole  of  the  chromatin,  the  stainable  mesh  substance  is  modified 
chromatin.     That   it   is   modified  and  no  longer   fully  functional    may 
be  seen  by  glancing  at  Figs.  13  and  14  which  represent  fully  formed  red 
corpuscles  of  the  larva  in  division.     Examples  of  the  latter  are  not  very 
numerous,  not  more  than  three  or   four  occurring  in  a  whole  series  of 
sections.      In  these  one  finds   that   there  is  a   quantity   of  chromatin 
between  the  loops  of  the  chromatin  figure  in  the  daughter  nuclei  and 
that  this  unorganised  chromatin  has  only  taken  a   passive  share  in  the 
process  of  division.     The  latter  species  of  chromatin  was  in  a  few  cases 
so  abundant  as  to  obscure  the  regular  chromatin  loops. 

The  .substance,  then,  in  the  spaces  of  the  nuclear  network  is  a  derived 
chromatin  which,  fixed  with  chromic  acid  or  Flemming's  Fluid,  gives 
with  alum-cochineal  or  alum-haematoxylin  a  deep  and  homogeneous 
stain  and  which  when  fixed  with  chromic  acid  has  the  property  of  giving, 
as  haemoglobin  does,  a  grass-green  stain  with  the  Indigo-carmine  Fluid.  I 
believe  this  modified  chromatin  is  the  parent  substance  of  haemoglobin, 
that  is,  it  is  a  true  haematogen. 

That  this  modified  chromatin  is  derived  from  the  primitive  chromatin 
of  the  haematoblast  is  also  shown  by  a  study  of  sections  from  the  spleen  of 
Necturus  hardened  in  chromic  acid  and  stained  with  the  Indigo-carmine 
Fluid.  Fig.  8  is  an  exact  representation  of  a  group  of  cells  from  one  of 
the  blood  sinuses  in  such  a  section,  in  which  a  dividing  haematoblast  is 


68 


TRANSACTIONS   OF    THI   CANADIAN    INSTITUTK. 


[Vol.  II. 


shown  with  the  chromatin  loops  alone  colored  grass-green  while  the 
cytoplasma  and,  if  present,  the  caryoplasma  are  colored,  in  contrast,  light 
red.  There  is  evidently  no  derived  or  modified  chromatin  here  and  the 
only  substance  related  to  it  must  be  situated  in  the  chromatin  loops.  I 
saw,  indeed,  in  a  number  of  other  examples  of  dividing  haematoblasts 
that  there  was  a  grass-green  substance  between  the  usual  chromatin 
loops  and  this  substance  which  was,  evidently,  modified  chromatin, 
varied  in  quantity  from  that  condition  where  it  was  scarcely  detectable  to 
that  where  it  was  so  abundant  as  to  obscure  the  outlines  of  the  similarly- 
stained  chromatin  loops.  The  latter  condition  is,  certainly,  a  later  stage 
than  that  shown  in  Fig.  8  and  the  nucleus  of  the  fully  formed  red  cell,  in 
all  probability,  represents  the  culmination  phase  of  the  conversion  of 
chromatin  into  ha;matogen. 

The  chromatin  of  ha;matoblasts  can  be  shown  to  be  different  in 
composition  from  that  of  an  ordinary  cell.  In  cio^r  *n  demonstrate  this 
one  must  resort  for  material  to  those  Amblystonia  larvae  in  which  the 
majority  of  the  blood  corpuscles  are  more  or  less  pigmented.  The 
latter  condition  can  be  readily  determined  by  putting  the  larva  in  water 
on  a  glass  slide  and  examining  its  gills  through  the  low  power  of  the 
microscope.  Indeed  almost  any  larva,  not  very  long  after  its  escape  from 
the  envelope,  will  answer  the  purpose.  It  is  fixed  in  Flemming's  Fluid  for 
half  an  hour,  then  put  in  5o7o  alcohol  for  fifteen  minutes,  afterwards  in 
70%  for  twenty-four  hours  and  finally  in  95%  for  four  or  five  hours.  If 
it  is  stained  in  toio  with  alum-haematoxylin,  imbedded  in  paraffin, 
sectioned,  and  the  sections  mounted  in  series  on  the  slide  in  benzol 
balsam,  one  can  in  the  concave  sides  of  the  aortic  arches  and  in  the 
developing  spleen  find  a  large  number  of  dividing  haematoblasts  which 
at  once  betray  their  presence  by  the  dull  slate,  or  slate-brown  color 
which  their  chromatin  possesses,  while  the  chromatin  of  ordinary  cells  is 
stained  a  tint  between  purple  and  navy-blue.  Figs.  9  a  and  b  are 
contrast  drawings  made  from  specimens  in  the  concave  side  of  the  same 
aortic  arch  and  in  the  same  section,  the  one  representinj  an  endothelial 
cell,  the  other  a  hccmatoblast.  In  the  latter  the  slate-brown  color  of 
the  cytoplasma  was  not  very  marked  and  this  may  frequently  be 
found  free  from  any  color  whatever.  No  more  decisive  proof  could  be 
given  that  the  chromatin  of  ha;matoblasts  differs  chemically  from  that 
of  ordinary  cells.  That  which  gives  with  the  ha;matoxylin  a  slate-brown 
color  is  probably  a  haematogen  or  haematogenous  chromatin. 

Flemming*  has  noticed  this  reaction  of  the  chromatin  of  the  ha;mato- 
blasts  on  the  haeniatoxylin,  and  he  states  that  dividing  haematoblasts 

•  Arch,  fiir  Mikr.  Anat.  Bd.  XVI.,  p.  396  and  Taf.  XVII.,  Figs.  19  and  20. 


•L.  II. 


1890  91.] 


AMPHIBIA    BLOOU   STUDIB8. 


09 


fixed  in  chromic  acid  have  in  the  unstaiu^d  condition  a  greenish-hnnvn  or 
brownish-yellow  color  which  he  considers  due  to  haemof^Iobin.  Tliis 
color  is  maintained  in  the  ha^matoxylin  staining  fluid  while  all  the 
nuclei  of  other  cells  become  blue.  I  also  have  observed  similarly 
colored  haematoblasts  in  chromic  acid  preparations,  and  I  attributed 
the  color  at  first  to  the  presence  of  h.emoglobin.  In  such  prepar- 
ations, however,  there  are  examples  in  which  the  chromatin  elements 
only  are  greenish-brown  or  brownish-yellow,  and  from  this  condition 
to  that  where  the  brownish-yellow  substanct.  is  so  abundant  as  to 
obscure  the  view  of  the  internal  structure  of  the  cell  there  are  all  shades 
of  transition.  This  substance  is  not  haemoglobin  but  ratiier  an 
antecedent  of  it,  that  is  haematogcn,  and  is  of  the  same  nature  and  origin 
as  the  modified  chromatin  in  the  nuclei  of  the  fully  formed  red  cells 
which  also  show  the  same  greenish,  greeni.-,u-brown  or  greenish-yellow 
color  when  they  have  been  treated  with  chromic  acid.  It  differs  from 
chromatin  in  its  action  on  haematoxylin  and  from  haemoglobin  in  that 
it  is  more  easily  fixed  with  hardening  reagents  in  the  cell,  and  in  that, 
as  I  will  now  show,  it  has  a  greater  capacity  for  staining  with  eosin. 

In  the  preparations  of  the  haematoblasts  of  larval  Amblystomata  fixed 
with  Flemming's  Fluid  and  stained,  as  described,  with  haematoxylin  and 
afterwards  with  eosin,  one  finds  the  modified  chromatin  or  h?ematogen 
stained  very  deeply  with  the  latter  reagent.  The  dividing  haematoblasts, 
according  to  this  reaction,  are  separable  into  the  following  divisions : 
(i)  those  in  which  the  cell  body  is  only  feebly  stained  while  the  chro- 
matin elements  are  stained  deep  terra-cotta  red  (Fig.  lo) ;  (2)  those  in 
v.'hich  the  cell  body  is  only  little  less  deeply  colored  terra-cotta  red  than 
the  chromatin  loops  (Fig.  11) ;  (3)  those  in  which  the  staining  in  the  cell 
body  presents  conditions  transitional  between  (i)  and  (2).  There  can 
be  no  doubt  that  in  these  forms  the  eo.sinophilous  substance  originates 
in  the  chromatin.  The  haematoblasts  are  the  only  cells  in  such  prepar- 
ations which  show  this  decisive  eosin  reaction. 

Now  this  modified  chromatin  or  htematogen,  as  I  prefer  to  call  it, 
when  once  secreted  into  the  cell  of  the  haematoblast  persists  there 
through  all  the  divisions  of  the  latter.  This  certainly  cannot  be  proved, 
and  I  believe  it  is  impossible  to  prove,  but  it  is  a  rea.sonable  inference 
from  facts  gained  by  a  careful  study  of  the  preparations.  After  a 
certain  stage  in  larval  life,  nearly  all  the  haematoblasts  show  it  to  be 
present  and  it  is  converted  into  hcemoglobin  when  the  cycle  of  divisions  has 
been  gone  through.  After  the  formation  of  hsematogen  once  commences 
it  goes  on,  with  the  result  that  each  of  the  numerous  daughter  or 
descendant  haematoblasts  possesses  by  inheritance  and  through  secretion 


60 


TKANSACTIONS   OP   THE   CANADIAN    INSTITUTE. 


[Vol.  II. 


H 


a  quantity  of  hjematogcn  as  definitely  as  it  has  unmodified  chromatin. 
This  h.-cmatogen  plays  no  part  at  all  in  the  division,  and  when  the  power 
of  division  is  lost  or  greatly  diminished  the  unmodified  chromatin  is 
confined  in  the  nuclear  membrane  and  the  terra-cotta-red  stain  in  the 
cell  body  gives  place  to  that  characteristic  of  haemoglobin. 

It  has  been  already  observed  by  Flemming*  that  chromatin  is  very 
abundant  in  dividing  haimatoblasts,  and  he  compares  this  great  volume 
with  that  of  the  same  substance  in  the  fully  formed  red  cells.f  He  also 
speculates  on  the  cause  of  the  increase  in  the  quantity  of  chromatin  and 
mentions  two  possible  explanations:  either  the  stainable  substance  is 
taken  fromthe  protoplasm  of  the  disc  into  the  nucleus  or  the  nuclei  of 
the  red  cells  contain  chromatin  in  a  greatly  condensed,  form  so  when  that 
division  commences  it  suffices  to  fill  out  the  enlarged  nuclear  figure. 
He,  apparently,  inclines  to  the  latter  view  because  the  nuclei  of  fully 
formed  red  cells  stain  mor^  deeply  than  do  those  of  other  cells,  yet 
expresses  himself  as  not  quite  certain  that  a  portion  of  the  protoplasm 
of  the  disc  does  not  go  into  the  nuclear  figure  in  division.  StrasburgerJ: 
adopts  the  second  explanation.  Flemming§  further  states  that  the 
mitotic  figure  in  the  hfematoblasts  is  2 — 3  times  greater  than  the  nucleus 
of  the  resting  or  fully  formed  cell. 

Flemming's  observation  as  to  the  great  amount  of  chromatin  present 
in  the  ha;matoblast  is  correct,  but  he  has  used  a  wrong  or  incorrect 
.standard  when  he  selected  the  nucleus  of  the  resting  red  cell.  I  have 
already  pointed  out  that  there  are  two  kinds  of  chromatin  in  the 
latter.  The  network  chromatin  is  never  reinforced  by  that  in  the 
spaces  of  the  network  and  it  alone  is  a  direct  descendant  of  the  mitotic 
chromatin  of  the  haematoblast.  This  is  very  clearly  shown  by  hsma- 
toblasts  one  of  which  is  represented  in  Fig.  14.  Now  the  original  chromatin 
of  the  hfematoblasts  is  from  the  time  of  their  differentiation  as  such 
specially  abundant.  The  quantity  of  this  substance  is  from  this  time  on 
to  that  of  the  formation  of  the  red  cells  so  great  that  the  h.-ema- 
toblast  seems  hardly  capable  of  containing  much  else,  and,  as  a  con- 
sequence, divisions  appear  so  rapidly  that  I  have  never  yet  succeeded  in 
observing  the  resting  stage  and  the  -same  has  been  the  experience  of 
other  observers.  There  is  in  this,  plainly,  a  reason  for  a  degeneration  of 
part  of  the  chromatin  into  the  eosinophilous  substance  already  described. 

*  Zellsubstanz  Kern-und  Zellthetlung,  p.  262-3. 

+  The  two  upper  cells  represented  in  his  fig.  T.  p.  263,  op,  cit.,  are  fully  developed  blood 


cells. 


J  Zellbildnng  und  Zelltheilung,  1880,  p.  330. 
§  Arch,  fiir  Mikr.  Anat.,  Bd.  XVI,  p.  396. 


181)0  91. J 


AMPHiniA    BLOOD   8TID1ES. 


CI 


When  the  amount  of  chromatin  has  become  30  much  reduced  by  division 
and  by  degeneration  of  itself,  then  and  it  till  then  is  reached  the  stage 
of  the  fully  formed  corpuscle.  Even  in  this  stage  there  may  be  just  so 
much  network  chromatin  left  as  to  prompt  a  .somewhat  imperfect  division 
(Figs.  12-14),  but  these  forms  are  extremely  rare  and  the  fully  formed  red 
corpuscle  is  incapable  of  division  henceforth,  in  other  words,  it  has  less 
than  the  usual  quantity  of  unmodified  chromatin  that  an  ordinary  cell  ha.s. 
It  may  be  seen  from  this  that  Flemming's  theory  of  the  condensation 
of  the  chromatin  of  haematoblasts  is  not  supported  by  the  example 
which  he  brought  forward.  The  chromatin  exists  in  the  h.tmatoblast.s 
from  the  first,  there  is  no  condensation  of  chromatin  in  the  nuclei  of  red 
cells,  but  there  is,  for  the  greater  part  of  it,  degeneration. 

Had  Flemming,  Pfitzner,  and  Strasburger  studied  fully  the  origin  and 
development  of  the  haematoblasts  they  would,  I  believe,  not  have  been 
puzzled  by  the  extraordinary  abundance  of  the  chromatin  therein  and 
Flemming  would  hardly  have  striven  to  account  for  this  abundance  in 
the  way  he  did,  either  by  derivation  out  of  the  cytoplasma,  or  by 
expansion  of  originally  condensed  chromatin. 

From  a  study  of  my  preparations  there  can  be  no  doubt  that  the 
eosinophilous  substance  of  the  haematoblasts  is,^on  the  one  hand,  denved 
from  the  chromatin  and  on  the  other,  transformed  at  the  close  of  hasma- 
toblastic  life  into  haemoglobin.  The  transformation  .sometimes  occurs 
before  this  epoch  for  in  the  freshly  shed  blood  of  larval  Ajiiblystoinata  I 
have  seen  mitotic  haematoblasts  in  which  a  faint  haemoglobin  coloration 
was  present  and  in  a  few  other,  somewhat  deeply  pigmented  cells  the 
addition  of  weak  acetic  acid  solution  dissolved  out  the  haemoglobin  and 
showed  mitotic  figures.  This  was  the  rare  exception  of  course.  I  do 
not  think  the  eosinophilous  substance,  although  it  also  deserves  to  be 
called  haematogen,  is  the  same  as  the  interfilar  or  modified  chromatin  of 
the  fully  formed  red  cells,  for  the  latter  does  not  react  so  definitely 
towards  eosin,  and  it  does  not  as  readily  affect  the  haeniatoxylin  in  the 
same  way.  As  I  have  shown,  they  both,  however,  are  derived  from  the 
same  source,  and,  apparently,  the  eosinophilous  substance  is  farther  on 
the  '.oad  to  the  formation  of  haemoglobin  than  the  other. 

There  are  a  number  of  facts  which  also  support  the  view  that  haemo- 
globin is  derived  from  chromatin.  Hunge*  has  extracted  from  the  yolk 
of  hen's  egg  and  from  milk,  nucleins  which  contain  iron  very  firmly  bound 
in  the  nuclein  molecule.  That  found  in  the  yolk  Bunge  especially 
calls  haematogen,  because  he  believes  that  it  is  the  antecedent  of  the 
haemoglobin  of  the  chick,  and  he  puts  forward  the  view  that  all  the  iron 


*Ueberdie  Assimilation  des  Eisens.     Zeit.  fiir  Physiol.  Chemie,  Bd.  IX.,  pp.  49-59' 


62 


TRANSACTIONS    OK    TIIU    CANADIAN    INSTITUTK. 


[Vol.  II. 


whicli  enters  tlie  animal  body  for  assimilation  does  so  in  firm  combina- 
tion with  complicated  orfjanic  compounds,  the  elaboration  of  which  occurs 
only  in  the  vegetable  kingdom.  Such  compounds,  he  contends,  when 
absorbed  and  assimilated,  yield  hitmoglobin.  Kossel*  has  corroborated 
Bunge's  observations  as  to  the  occurrence  of  iron  in  the  nucleins  of  yolk 
and  milk. 

Furthermore,  Zaleskif  found  in  the  livers  of  various  animals,  washed 
out  and  thoroughly  freed  from  h;emoglobin  and  inorganic  iron  salts,  pro- 
teids  which  contained  iron  more  or  less  firmly  combined.  These  were 
albuminates  of  iron  (Albuminat-verbindung  des  F.isens),  and  two,  probably 
three,  nucleins  containing  iron  (Nucieo-verbindungen  des  Eisens).  The 
latter  vary  in  the  power  with  which  they  hold  the  iron,  and  in  one  of  the 
nucleins  which  he  calls  hcpatin  the  iron  is  so  firmly  combined  that  the 
ordinary  tests  fail  to  show  its  presence,  /'/  being  only  detected  in  the  as/t. 
This  hepatin  differs  from  the  haematogen  of  Bunge  in  thuc  the  latter 
yields  up  its  iron  more  readily  and  has  a  greater  amount  of  the  metal, 
the  h.tmatogen  containing  0297oi  the  hepatin  0'oii7o-  Zalesk  ,  more- 
over, determined  that  his  iron-holding  nucleins  are  present  in  the  nuclei 
of  the  hepatic  cells. 

These  nucleins  have  all  the  characters  of  the  ordinary  nucleins  isolated 
from  pus,  semen,  etc.,  and  as  the  latter  are  supposed  to  be  present  in,  or  to 
form  the  sub.stance  known  as  chromatin  to  the  cytologist,  it  is  possible 
that  chromatin  usually  if  not  always  contains  iron  as  firmly  bound  as  in 
the  ha.'niatogen  of  Bunge  and  in  the  hepatin  of  Zaleski.  It  is  true  that 
the  analyses  of  nucleins,  as  given  generally,  do  not  point  to  the  occurrence 
of  iron,  but  this  can  be  explained  by  reference  to  the  method  employed 
in  their  preparation.  The  nucleins,  or  rather  chromatins,  are  soluble 
in,  and  after  a  short  time  decomposed  by,  alkalies.  Bunge  has 
shown  that  his  hiematogen  loses  its  iron  in  solutions  of  potassic  hydrate 
after  some  days  and  contact  with  ammonic  sulphide  causes  its  decompo- 
sition with  the  separation  of  sulphide  of  iron.  In  the  preparation  of 
nucleins  alkaline  fluids  have  been  u.sed'to  dissolve  the  residue  left  by 
digesting  tissues,  pus,  etc.,  with  pepsin  and  weak  hydrochloric  acid,  or 
with  hydrochloric  acid  alone,  and  the  alkaline  fluid  used  contains  the 
nucleins  (soluble  variety)  which  one  would  expect,  from  the  results  of 
Bunge's  researches^  to  be  free  from  iron  (combined),  if  originally  they  con- 
tained it.     In  this  way  we  may  explain  why  the  nucleins  from  various 

•Weitere  Beitrage  zur  Chemie  des  Zellkerns.     Zeit.  (ur  Physiol.  Chemie,  Bd.  X.,  p.  249. 
tStudien  uber  die  Leber.  I.  Eisengehalt  der  Leber.    Zeit.   fiir  Physiol.  Chemie,  Bd.  X.,  pp. 
452-502. 

JSee  on  this  subject  specially  the  appendix. 


1890-91.] 


AMPHIBIA    BLOOD   8TUDIK8. 


G3 


sources  analysed  by  different  chemists  present  so  many  variations  in 
composition  as  to  lead  some  observers,  Gam^,'ce*  amon^jst  them,  to  deny  a 
chemical  individuality  to  these  substances.  The  nucieins  so  extracted 
can  hardly  be  considered  as  more  than  derivatives  of  the  chromatin 
substances,  for  the  latter  in  the  living'  cell  is  undoubtedly  the  scat  of  the 
more  important  vital  processes,  and  the  changes  rcsultin;^  in  these  vital 
phenomena  can  hardly  occur  in  a  compound  so  comparatively  simple  as 
the  nuclein,  to  which  Miescher  ascribed  the  formula  C.^^  M^„  N„  I*,,  O.... 

I  have  succeeded  during  the  last  summer  in  definitely  demonstrating 
that  the  great  part,  if  not  the  greater  part  of  the  yolk  of  the  ovum  of  the 
frog  and  of  Necturus  is  derived  by  diffusion  from  the  chromatin  o( 
nucleus  of  the  ovumf.  Now  this  chromatin  so  diffused  is  the  analogue  in 
amphibian  egg  of  the  ha.Mnatogen  of  the  hen's  egg.  This  taken  in  con- 
junction with  the  fact  that  the  iron-holding  nuclein  of  milk  can  apparently, 
and  possibly,  only  be  the  chromatins  which  Nissen*  has  shown  that  the 
degenerating  cells  of  the  mammary  gland  throw  out  into  the  lumen  of 
the  secreting  tubules,  distinctly  points  to  the  presence  of  iron  firmly  com- 
bined in  the  chromatin  of  every  cell. 

All  these  points  support  and  confirm  the  view  that  the  haimoglobin  of 
the  blood  is  derived  from  the  chromatin  §  of  the  h.-cmatoblasts.  It  may 
be  asked,  Why  if  chromatin  contains  iron,  should  not  all  cells  contain 
hnemoglobin  ?  All  cells  do  not  contain  the  excess  which  ha^matoblasts 
have,  and  therefore  have  none  to  spare  for  transformation  into  that  com- 
pound. Why  the  hasmatoblasts  have  an  excess  of  chromatin  I  shall 
endeavor  to  show  when  I  come  to  speak  of  their  origin  further  on. 
Enough  has  been  said  to  show  that  the  compounds  which  Bunge  and 
Zaleski  isolated  and  called  respectively  hcematogen  and  hepattn  do  not 
merit  these  names,  the  haematogen  not  going  directly,  except  probably  in 
developing  muscle  fibre  in  larval  amphibia,  to  form  haemoglobin,  v  hile 
Zaleski  has  not  shown  that  every  cell  of  the  body  does  not  contain  a 
nuclein  in  which  the  iron  is  as  firmly  combined  as  in  the  so  called  hcpatin. 

As  an  additional  proof  that  haemoglobin  is  derived  from  chromatin,  the 
occurrence  of  phosphorus  in  the  haemoglobin  of  the  blood  of  the  goose 
may  be  quoted.     It  is  suspected  by  many  that  the  phosphorus  belongs 


•Physiological  Chemistry  of  the  Animal  Body,  Vol.  I.,  p.  243. 

tThe  results  of  the  research  will  be  published  shortly. 

t\rch.  fiir  Mikr.  Anat.,  Bd.  XXVI.,  p.  337. 

§  I  am  inclined  to  believe,  from  the  results  of  my  own  observations,  that  the  hjemoglobin  of 
muscle  fibre  in  Amphibia  is  derived  directly  from  the  yolk  chromatin  or,  as  Bunge  calls  it, 
hsematogen. 


64 


THANHACTI0N8   OF   TBI   CANADIAN    INHTITUTK. 


[Vol.   II. 


li 


|i; 


to  a  compound  which,  in  no  way  uniting  with  the  ha:moglobin,  yet  in  an 
admixture  with  it,  is  so  difficult  to  separate  that  after  many  crystallizations 
of  the  h.L-moglobin  some  will  always  adhere  to  the  crystals.  Recently^ 
however,  Jacquet*  has  isolated  the  ha;moglobin  of  hen's  blood  alter 
recrystallization  and  has  found  that  it  contains  0'I97%  of  phosphorus 
and  0335/i  of  iron.  Hoppe-Seyler  had  previously  found  in  the  h.xmo- 
globin  of  goose's  blood  077%  of  phosphorus  and  0"437o  ^^  ''O"-  '^^^ 
anomaly  of  the  presence  of  phosphorus  in  the  hsemoglobin  of  Avian 
blood  is  readily  explained  away  by  the  fact  that  the  ha-moglobin  is 
derived  from  a  class  of  prottids  which  are  peculiar  in  containing  phos- 
phorus. 

It  is,  indeed,  an  important  question  whether  the  chromatin  of  all  cells 
docs  not  act  as  an  oxygen-absorber  like  hsmoglobin.  I  made  some 
experiments  on  this  point.  Methylene  blue  in  living  tissues  in  which  the 
metabolic  processes  are  vigorous  becomes  discolored  owing  to  the 
abstraction  of  oxygen.  This  reagent  has  been  recently  much  used  on 
this  account  in  the  determination  of  the  course  of  nerve  fibres.  Into 
solutions  of  this  dye  I  put  a  number  of  free-swimming  Lrval  Amblysto- 
mata  and  examined  them  from  time  to  time  to  determine  the  effect  on 
the  cells  of  the  gills  and  in  the  tail.  With  weak  solutions  I  found  the 
free  portions  of  the  membranes  only  of  the  epithelial  cells  colored,  while 
with  gradually  increasing  strength  of  solution  granules  in  the  cytoplasma 
of  the  same  cells  become  stained,  especially  those  between  the  radicles 
of  the  cilia  on  the  gills.  Sometimes  a  red  blood  corpuscle  presents  in 
the  disc  in  this  case  one  or  more  blue  granules.  If  one  increases  the 
strength  of  the  reagent  almost  up  to  the  limit  of  endurance  on  the  part 
of  the  animal,  other  cytoplasmic  elements  are  stained,  but  in  no  instance 
have  I  seen  a  single  nuclear  body  stained.  This  was  not  due  to  slower 
penetration  and,  therefore,  readier  deoxidation,  or  reduction  of  the  dye,  for, 
in  the  few  examples  of  epithelial  cells  in  division  which  I  found  in  that 
stage  in  which  the  nuclear  membrane  is  absent,  the  chromatin  elements 
were  absolutely  colorless.  Indeed,  it  is  only  when  the  dividing  cell  is 
moribund  or  dead  that  the  chromatin  elements  stain  at  all.  The  pro- 
bable explanation  of  the  phenomena  described  is  that  the  chromatin  has 
a  marked  capacity  for  storing  up  oxygen  in  itself  and  that  it  differs  from 
haemoglobin  in  that  it  gives  up  this  element  only  to  the  products  of  its 
metabolism. 

If  chromatins  and  the  iron-holding  proteids  derived  from  them,  like 
the  yolk  nuclein  of  Bunge,  have  the  capacity  of  storing  up  oxygen,  then 
it  is  possible  that  part  of  the  oxygen  required  for  respiratory  purposes  in 


•Zeit.  fUr  I'hysiol.  Chemie.,  Bd.  XIV.,  pp.  289-296. 


I 


1H!)0-91.] 


AMHIIIHIA    HLOOD    NTI'DIKK. 


05 


the  yolk-holding  ova  may  be  derived  from  this  source.  It  is  somewhat 
difficult,  otherwise,  to  explain  the  process  of  respiration  in  larval  Ambly- 
stoinata  which  pass  a  week  or  more  imbedded  dcejjly  in  i,'elatinous  masses 
floating  in  stagnant  ponds. 

I  have  seen,  in  a  few  cases,  the  straw-yellow  crystal-like  bodies  in  the 
immediate  neighborhood  of  the  nuclear  membr.inc  as  Cucnot*  has  de- 
scribed. I  have  represented  in  l''ig.  26  the  arrangement  of  the  bodies 
but  they  are  not  always  a^  clo-fcly  applied  to  the  nucleus  as  there  slu)wn, 
for  they,  in  the  greater  number  of  cells  in  which  they  were  found,  lie  free 
in  an  apparently  empty  space  between  nuclear  and  cell  membranes.  I 
regard  all  these  cells,  as  well  as  those  describeil  by  Cuenot — who  believes 
that  they  indicate  the  secretion  of  luenjoglobin  from  the  nucleus — as  the 
products  of  pathological  comlitions.  I  have  not  seen  more  than  half  a 
dozen  of  such  cells  and  yet  I  have  diligently  examined  the  fresh  blood 
of  several  hundred  larVf^e  in  various  stages  of  development. 

Research  demonstrates  more  and  more  the  influence  which  the  nucleus 
exercises  on  the  nutrition  anJ  function  of  the  cell  and  among  the  obser- 
vations put  forward  in  this  lim;  those  of  Korscheltf  may  be  mentioned, 
in  which  it  is  shown  that  the  formation  of  chitin  is  directly  dependent 
on  tlje  nucleus.  Among  the  covering  cells  of  the  ova  of  Nepa  and 
Ranaira  the  nuclei  of  two  fused  cellular  elements  approach  each  otiier  and 
enclose  between  them  a  cavity  in  which  chitin  is  deposited.  PlatnerJ 
also  considers  that  the  derivation  of  enzymes  in  gland  cells  takes  place 
by  the  constriction  and  separation  of  a  portion  of  the  nucleus  and  the 
subsequent  formation  of  zymogen  granules  at  the  same  time  that  the 
chromatin  of  the  separated  nuclear  portion  is  undergoing  degeneration 
and  absorption  in  the  cytoplasma.  He  believe^  that  there  is  a  direct 
causal  relation  between  th^  budding  of  the  nucleus  with  the  subsequent 
degeneration  of  the  separated  part  and  the  formation  of  zymogen 
granules.  I  have  failed  to  find  that  Platner's  description  is  true  so  far 
as  formation  of  zymogen  in  the  pancreatic  cells  of  amphibia  is  concerned, 
but  I  have  found,  nevertheless,  that  the  nuclei  of  these  cells  play  a  very 
important  part  in  the  elaboration  of  the  zymogen.  It  is,  also,  evident 
from  the  trend  of  researches  in  vegetable  cytology  that  the  nuclei  of  green 
cells  are  the  important  factors  in  the  elaboration  of  carbohydrates  and 
that  the  latter  are  converted  into  starch  in  the  chlorophyll  grains.§ 

•Comptes  Rendus.     1888.     p.  673. 

tUeber  einige  interessante  Vorgange  bei  der  Bildung  der  Insekeneier.  Zeit.  (Ur  Wiss.  Zool., 
Bd.  45- 

*  Arch.  fUr  Mikr.  Anat.,  Bd.  XXXIII.     p.  180. 

§  See  on  this  point  Strasburger's  Histologische  Beittage.  Heft  I. :  Ueber  Kern  und  Zellthei- 
lung  im  Pflanzenreiche,  pp.  194-204. 


66 


TRANSACTIONS    OF   THK   CANADIAN    INSTITUTE. 
II.     THK    FUSIFORM    COKPUSCLES. 


[Vol.  II. 


The  f  viiform  corpuscles,  which  measure  26/1  x  16/^,  are  quite  numerous 
in  the  shed  blood  of  Necturus.  They,  as  their  name  impUes,  are  elong- 
ated and  oval,  and  with  usually  sharply  truncated  ends.  They  have  no 
ceil  membrane,  and  their  protoplasm,  especially  at  one  or  both  of  the 
ends,  is  amctboid  or  protrusible  in  the  form  of  fine  straight  rays,  which, 
with  careful  observation,  are  sometimes  seen  to  manifest  a  slow  vibratory 
motion.  Sometimes  these  cells  are  fi.ved  with  the  processes  extended 
(Fig.  22b).  Often  the'  protoplasmic  periphery  is  formed  of  a  series  ot 
granules  which  render  the  exact  outline  indistinct.  The  protoplasm  is 
usually  homogeneous,  e.xccpt  for  the  presence  of  one  or  more  vacuoles  at 
either  end  of  the  oval  nucleus  and  a  few  granules  which  seem  to  be  of 
the  same  character  as  those  of  the  periphery. 

The  nucleus  is  oval  usually  and  measures  i6/jix  14/^  It  may  in  some 
cases  be  lobed,  and  the  jobation  may  have  gone  so  far  as  to  originate 
several  small  spherical  nuclei.  It  may  be  homogeneous  or  it  may  be 
coarsely  reticulated.  Kept  in  a  moist  chamber  the  reticulated  as  well  as 
the  homogeneous  nuclei  undergo  a  process  of  chromatolysis.  In  the  case 
of  the  reticulated  nuclei  the  first  stage  of  degeneration  is  seen  in  the  tra- 
beculae  of  the  network  becoming  elongated  and  paraliel,  the  elongation 
occurring  transversely  to  the  long  axis  of  the  nucleus.  At  the  same  time 
the  spaces  in  the  network  become  larger  and  the  nucleus  apparently 
distended.  This  condition  passes  into  that  wherein  the  whole  nuclear 
substance  becomes  homogeneous  or  in  whieh  its  chromatin  forms  a  thick 
zone  next  to  the  now  spherical  membrane.  The  history  of  the  corpuscle 
terminates  with  the  disintegration  of  the  whole  into  globules  more  or 
less  spherical  and  varying  in  size,  suspended  in  the  serum.  Very 
little  of  the  cytoplasma  is  found  in  connection  with  these  globules, 
for,  whih  the  nucleus  is  passing  through  the  conditions  described,  the 
cytoplasma  granulates  and  becomes  dissolved  in  the  serum. 

Such  is  the  fate  of  the  fusiform  corpuscle  when  it  lies  by  itself. 
When,  however,  it  meets  with  another  the  two  fuse,  either  by  their 
ends,  as  is  commonly  the  case,  or  by  their  sides,  and  this  capacity 
for  fusion  may  be  exercised  so  much  that  small  masses  of  them  (white 
thrombi)  exist  here  and  there  over  the  field  of  the  preparation.  The 
fusion  is  complete,  all  the  lines  of  demarcation  disappearing,  even  the 
granules  which  formed  the  protoplasmic  periphery  being  dissolved. 

These  corpuscles  are  free  from  color  and  are  like  the  leucocytes  in 
many  respects.  From  the  latter  they  are  distinguished  by  the  absence 
of  true  amcEboid  movement  and  by  their  regular  shape  and  size. 


181)0-91.] 


AMPHIBIA    BLOOD    STUDIES. 


67 


I  have  now  to  discuss  the  na'ure  of  these  corpuscles  and  will  first  of 
all  detail  the  various  views  which  have  been  advanced  concerning  them 
in  this  respect. 

It  is  probable  that  the  first  observation  of  these  corpuscles  was  made 
by  von  Recklinghausen*  in  1866,  who  described  structures,  which  could 
have  been  no  other  than  fusiform  cells,  in  his  preparations  undergoing 
transformation  into  red  cells.  He  found  all  the  stages  of  transition  between 
the  spindles  (fusiform  cells)  and  the  elliptical  (red)  corp'iscles,  while  he  saw 
under  favorable  conditions  in  .some  of  the  spindles  a  red  .shade  like  that  in 
the  ordinary  red  cells  and  he  regarded  thcs .  colored  spindles  as  develop- 
ing red  cells.  He  refers  to  the  fact  that  in  his  preparations  there  are  at 
first  small  white  points,  afterwards  becoming  flat  islands  (white  thrombi?) 
consisting  of  contractile  cells  which  attain  enormous  sizes  and  possess 
contractile  processes.  In  the.se  large  cells  are  developed  homogeneous, 
refracting  spheres,  .sometimes  to  the  number  of  forty,  which  may,  or  may 
not,  be  considered  as  endogenously  formed  cells. 

Ranvierf  is  the  next  to  refer  to  these  elements  in  frog's  blood.  He 
describes  them  as  .sometimes  sharply  pointed  at  both  ends  or  with  one 
end  rounded,  the  other  pointed,  finely  granular  and  uncolored.  He 
considers  them  to  be  free  endothelial  cells. 

HayemJ  regards  these,  as  well  as  the  platelets  of  mammalian  blood, 
as  haematoblasts.  He  describes  them,  as  they  occur  in  frog's  blood,  as 
smooth,  homogeneous,  slightly  clouded  and  with  a  tint  less  silvery  than 
that  of  the  white  corpuscles.  They  present  sometimes  a  central  area 
lightly  shaded,  occupying  the  place  of  the  nucleus,  and  inside  this  one  or 
two  refracting  granules.  The  nucleus  is  in  every  respect  like  that  of  the 
red  cell,  oval,  nucleolated  and  finely  granulated.  The  disc  which  is  small 
in  volume  is  flattened,  has  an  elongated,  variable  form  and  contains,  like 
the  red  cells,  two  distinct  con.stituents,  a  stroma  and  a  specially  organized 
substance.  The  stroma  is  very  delicate  and,  therefore,  more  difficult  to 
demonstrate  than  in  red  cells.  The  organized  matter  pervading  the 
stroma  differentiates  the  haematoblasts  from  the  red  cell,  and  it  is  un- 
colored or  faintly  tinted  with  a  small  quantity  of  haemoglobin  which  it 
loses  easily.  This  substance  is  extremely  diffusible,  and  it  is  endowed 
with  a  particular  kind  of  contractility.  It  is  very  easily  injured,  and  to 
this  property  is  due  the  formation  of  these  corpuscles  so  readily  into 
granular  masses.      Hayem  subjected  frogs  to  repeated  bleedings  and 


'j 


•Ueber  die  Krzeugung  von  rothen  Blutkorperchen.    Arcli.  (Ur  Mikr.  Anat.,   Bd.  II.,  .S.  137. 
tTraitd  technique  d'histologie,  1875,  p.  191  and  192. 

tArchives  de  Physiologic,  Tome  5,  1878,  Tome  6,  1879.     Also  a  later  publication  :  Du  .San; 
et  de  ses  altetations  anatomiques.     Paris,  1889,  pp.  I24>I5I. 


'  • 


i 


lii 


68 


TRANSACTIONS    OF   THE   CANADIAN    INSTIIUTK. 


[Vol.  II. 


found  in  the  blood  finally  all  the  intermediate  stages  between  the  fusi- 
form and  the  red  cells. 

Hizzozero  and  Torre*  reject  this  view  of  the  haematoblastic  nature  of 
the  red  cells  and  state  that  though  they  are  like  red  cells  in  some  respects 
they  are  smaller  and  unpigmented,  while  young  blood  cells  are  round  in 
form  and  always  contain  haemoglobin.  These  elements  are  also  unlike 
the  leucocytes  in  their  simple  oval  nucleus  and  non-contractile  proto- 
plasm. These  authors  believe  that  the  corpuscles  in  question  are  related, 
in  spite  of  many  points  of  dissimilarity,  to  the  structures  in  mammalian 
blood  known  as  platelets. 

Hlavaf  considers  the  fusiform  corpuscle  to  be  a  variety  of  the  white 
cell  brought  about  by  the  contractile  capacity  of  the  latter. 

LowitJ  describes  the  transformation  of  the  sp'ndles  into  spherical  forms 
like  that  of  the  white  cells  with  which  he  classes  these  elements.  He 
maintains  that  all  forms  of  white  blood  cells  may  appear  in  the  spindle 
form,  but  he  admits  that  certain  stages  of  the  developing  red  cell  exist 
in  this  form  from  which  haemoglobin  is  absent.  According  to  his  view 
the  fusiform  cell  is  not  a  separate  species  of  white  blood  cell  but  only  a 
form  of  the  latter  which  may  appear  under  those  conditions  offered  by 
the  circulating  blood,  and  it  may  in  some  cases  have  a  haematoblastic 
nature. 

Eberth§  describes  the  elements  as  being  spindle,  club,  or  almond- 
shaped,  somewhat  smaller  than  the  red  discs,  probably  slightly  flattened, 
possessing  a  finely  granulated  nucleus  and  an  almost  homogeneous  cell 
protoplasm  which  is  chiefly  gathered  at  the  poles.  Their  contour  does 
not  change,  they  have  no  amoeboid  processes,  and  when  they  are 
collected  into  great  masses  they  never  present  a  trace  even  of  a  yellow 
or  haemoglobin  tint.  When  they  are  Viept  for  hours  in  their  normal 
physiological  condition,  e.  g.,  inside  the  bloodvessels  of  an  excised  piece 
of  mesentery,  protected  from  evaporation,  they  have  never  been  observed 
to  change  in  .shape,  they  exhibit  no  amoeboid  movement  whatever  and 
they  do  not  fuse  together.     In  the  spindles  fixed  by  osmic  acid  there  is 

•Virchow's  Arch.,  Bd.  90. 

+Die  Beziehung  der  I31utplattchen  Bizzozero's  zur  Blutgerinnuiig  und  Thrombose.  Arch,  fiir 
Experim.     Pathologic,  Bd.  XVII.,  1883. 

>Ueber  Neulnlduiig  and  Zerfall  weisser  Blulkorperchen.  Sitzungsber.  der  Wiener  Akad., 
Bd.  XCII.,  Abth.  III.,  1885. 

Also:  Ueber  den  dritten  Formbestaiidtheil  des  Blutes.  "Lotos,"  Jahrbuch  fiir  Natur- 
wissenschaft.     Prag,  1885. 

§Zur  Kentniss  der  Biutkorperohen  bei  den  niedern  Wirbelthieren.  Festschrift  fUr  Kolliker 
Leipzig,  1887,  p.  37. 


)L.  11. 

fusi- 


1890-91.] 


AMPHIBIA    BLOOD    STUDIES. 


60 


V 


the  longitudinal  stripe,  or  folding,  described  by  Hayem  and  Bizzozero 
and  Torre  and  several  refracting  bodies  in  the  nucleus,  with  one  larger 
and  rounder  than  the  rest  to  represent  a  nucleolus. 

The  spindles  undergo  change  quickly  under  the  microscope  with  the 
ordinary  conditions  of  observation.  Their  protoplasm  swells  up  and 
disintegrates  into  a  quantity  of  fine  granules  which  partly  dissolve  and 
leave  a  faint,  somewhat  irregular  body  in  which  the  nucleus  still  persists. 
The  chromatin  in  the  nucleus  of  the  ordinary  spindle  is  more  irregular 
in  its  arrangement  and  more  fully  developed  than  in  the  white  cells,  and 
it  does  not  form  a  network  as  in  the  latter  or  in  red  cells. 

As  salient  points  in  their  character,  Eberth  emphasizes  their  colorless- 
ness  and  their  lack  of  amoeboid  movement,  both  of  which  separate  them 
from  the  white  and  red  cells.  They  are  not  young  red  blood  cells,  for 
these  even,  in  division,  contain  from  their  beginning  haemoglobin.  That 
the  fusiform  cells  do  not  contain  even  the  slightest  trace  of  haemoglobin  • 
is  shown  by  the  fact  that  thick  masses  of  them  have  not  the  faintest 
color,  which  would  not  have  been  the  case  if  some  of  them  contained 
haemoglobin.  Hayem  regarded  them  as  haematoblasts  in  his  first  paper, 
but  the  phenomena  of  Karyokinesis*  in  haemoglobin-holding  blood  cells 
was  then  unknown,  and  it  is  probable  that  he  mistook  the  true  haemo- 
globin-holding haematoblast  for  the  forms  intermediate  between  the 
fusiform  and  the  red  cells. 

Eberth  does  not  advance  any  view  as  to  the  origin  or  nature  of  the 
fusiform  elements,  simply  contenting  himself  with  pointing  out  the 
analogies  between  them  and  the  platelets  of  mammalian  blood. 

It  will  be  seen  by  a  comparison  of  the  above  views  that  von  Reckling- 
hausen and  Hayem  postulate  the  presence  of  hremoglobin  in  the  fusiform 
elements  while  Bizzozero  and  Torre  and  Eberth  deny  this.  Again, 
Hayem  and  Hlava  state  that  it  is  contractile  and  this  is  expressly 
opposed  by  Eberth.  Hayem  considers  them  to  be  haematoblasts,  with 
Hlava  they  are  white  corpuscles  or  a  variety  of  the  same,  while  with 
Bizzozero  and  Eberth  they  can  only  be  compared  to  the  platelets  of 
mammalian  blood.  Such  constitutes,  in  brief,  the  diversity  of  views  as  to 
their  nature. 

My  own  view  is  that  these  elements  represent  the  remains  of  the 
destroyed  or  broken  up  red  cells  and  the  following  are  the  facts  on  which 
the  view  is  based  : 

I.  Their  nuclei  are  oval  and  nearly  the  same  in  size  as  those  of  the 
red  ceils  {l6fix  14/n.  and  20/ax  I2ix  respectively).     The  difference  between 

•In  his  more  recent  work  (Uu  Sang  Ac.)  all  reference  to  these  points  is  omitted. 


70 


TRANSACTIONS   OF   THE   CANADIAN    INSTITUTE. 


[Vol.  II. 


ifi 


ii 


the  two  in  the  latter  respect  is  caused,  I  maintain,  by  the  nucleus  of  tlie 
fusiform  cell  enlarging  in  its  transverse  diameter  and  dininishing 
consequently  in  its  longitudinal  diameter.  If  one  keeps  a  specimen 
of  blood  under  observation  for  a  while,  during  which  it  is  protected 
from  evaporation,  one  finds  that  the  nuclei  of  the  fusiform  elements 
actually  undergo  this  enlargement  in  its  transverse  diameter,  the  trans- 
versely placed  trabeculae  of  its  network  elongate  till  the  chromatin 
appears  arranged  in  a  number  of  parallel  bars  transversely  placed.  One 
can,  moreover,  by  sudden  pressure  on  the  cover  glass,  rupture  a  number 
of  red  cells,  set  free  their  nuclei  which  undergo  the  same  series  of 
changes  that  the  nuclei  of  the  fusiform  cells  do,  and  shortly  after  the 
rupture  the  nuclei  of  the  red  cells  measured  exactly  the  same  (i6/^x  13^ 
and  14/t).  In  the  free  nuclei  there  is  the  same  transverse  enlargement, 
the  chromatolysis  and  nuclear  disintegration. 

2.  When  a  number  of  nuclei  of  red  cells  are  set  free  by  pressure  there 
is  the  same  tendency  to  adhere  to  each  other  that  is  so  marked  in  the 
case  of  the  fusiform  element.  To  each  of  these  free  nuclei  there  is 
enough  of  cytoplasma  adherent  to  constitute  the  cement  necessary  to 
agglutinate  them  together,  and  in  the  masses  so  formed  there  is  nothing 
to  distinguish  them  from  the  thrombi  formed  of  fusiform  cells.  I  have 
not  yet  succeeded  in  observing  in  them  any  pseudopodial  movement,  but 
it  is  not  often  that  this  is  observed  in  the  fusiform  elements  and  it  is 
possible  that  it  is  the  result  of  a  survival  from  a  well  nourished  condition 
in  the  blood  vessels,  ri  condition  not  at  all  present  under  the  cover  glass. 

3.  The  free  nuclei  and  those  of  the  fusiform  elements  have  the  same 
staining  reactions.  In  a  cover  glass  preparation  fixed  with  corrosive 
sublimate  or  picric  acid,  in  which  free  nuclei  are  abundant,  the  latter,  as 
well  as  those  of  the  fusiform  cells,  give  with  the  Indigo-carmine  Fluid  a 
blue-black,  sometimes  an  intense  black,  and  with  haematoxylin  a  black 
reaction.  In  fact  there  is  the  same,  or  nearly  the  same  stain  with  all  the 
dyes.  There  is  one  important  difference  so  far  as  the  cytoplasma  of 
both  is  concerned  :  eosin  takes  intensely  the  cytoplasma  of  the  fusiform 
cells  while  it  stains  lightly  or  not  at  all  the  slender  protoplasm  around 
the  free  nuclei.  The  explanation  of  this  is  that  the  interfilar  chromatin 
(the  haematogen)  of  the  nucleus  of  the  ruptured  red  cell  gradually  diffuses 
out  from  the  nucleus  into  the  cytoplasma  without  being  converted  into 
haemoglobin,  as  it  is  in  the  normal  corpuscle  and  that  it  is  this  altered 
chromatin  which  takes  eosin  deeply.  In  some  of  the  fusiform  cells  there 
is  the  same  differentiation  of  the  nuclear  substance  into  network  and 
interfilar  chromatin,  the  latter  staining  deeply  with  eosin,  the  former  with 
haematoxylin.     There  can  be  no  doubt   about  the  fact  that  in  such  cells 


)L.  ir. 

f  the 

inieii 
lected 
iients 
rans- 

<itiii 
One 
iTiber 
s  of 

the 

lent, 


1890-91.] 


AMPinniA    BLOOD    8TUDIKS. 


71 


the  nuclear  chromatin  is  arranged  in  the  form  of  a  network  in  every 
respect  like  that  in  the  nucleus  of  the  red  cell.  In  such  cases  one 
rarely  finds  the  Indigo-carmine  Fluid  to  react  as  it  does  in  the  nuclei 
of  the  intact  red  cells,  giving  a  light  red  stain  to  the  intcrfilar  chromatin 
and  a  green  or  a  bluc-grecn  color  to  network.  These  are  evidently  cells 
which  have  had  but  a  very  short  history  as  fusiform  cells,  that  is,  they 
have  been  but  recently  formed,  while  the  other  elements  which  do  not 
sViow  these  peculiarities  are  more  pathological  by  reason  of  their  longer 
existence  as  fusiform  celLs. 

4.  The  nuclei  of  these  elements  are  admitted  by  Bizzozcro,  Ilayem, 
to  present  resemhlances  to  those  of  the  red  cells.  These  observers, 
however,  took  for  study  the  blood  of  animals  in  which  tiie  red,  white  and 
fusiform  cells  are  comparatively  small,  and  consequently  were  unable  to 
determine  the  more  important  points  of  resemblance. 

We  can,  therefore,  on  the  view  that  the  fusiform  e'ements  are  the 
remains  of  ruptured  red  cells,  explain  the  absence  of  a  membrane,  the 
capacity  for  adhering  to  each  other,  the  similarity  in  shape,  size,  .structure 
and  staining  reactions  between  their  nuclei  and  those  of  the  red  cells 
when  freshly  ruptured.  We  can,  moreover,  explain  their  occurrence 
thereby  without  referring  in  any  way  to  the  ha;matoblasts  or  to  the 
leucocytes,  and  we  have  also  explained  to  a  certain  extent  the  fate  of  the 
red  cells — what  was  not  done  before. 

One  can  readily  determine  the  fate  of  the.se  fusiform  corpuscles  even 
in  cover-glass  preparations  of  Necturus  blood  fixed  with  osmic  acid, 
picric  and  especially  corrosive  sublimate.  Fig.  22  a  represents  a  fusiform 
corpuscle  in  which  there  is  a  distinct  and  coarse  chromatin  network  with 
a  certain  amount  of  interfilar  chromatin.  At  a  later  stage  the  trabeculae 
of  this  network  become  thinner  and  finally  disappear,  and  when  this 
happens  the  whole  nucleus  takes  a  uniform  stain  with  various  dyes. 
Sometimes  the  nodal  points  of  this  network  alone  persist  and  may 
appear  as  nucleoli.  In  the  now  homogeneous  nacleus  lobation  may 
ensue  (Fig.  22  c,  e.  /.),  and  the  lobation  may  go  so  far,  accompanied  by 
a  transformation  of  the  shape  into  that  of  a  more  or  less  round  mass,  as 
to  render  them  extremely  like  leucocytes.  Tliey  possess  now  no  amoe- 
boid properties  whatever,  and  their  cytoplasma,  which  is  now  compara- 
tively abundant,  begins  to  lose  its  eosinophilous  character  while  the 
nuclear  chromatin  reacts  less  readily  and  more  feebly  to  dyes.  As  such 
they  are  broken  up,  probably  in  the  circulation  and  more  especially  in 
the  vessels  of  the  spleen. 

As  factors  operating  in  the  production  of  the  fusiform  cells,  mechani- 


72 


TRANHACTI0N8   OF    THE   CANADIAN    INSTITUTK. 


[Vol.  II. 


M' 


||; 


1^ 


cal  conditions  inside  the  blood  vessels  may  be  mentioned.  It  always 
appeared  to  me  that  my  cover  preparations  were  far  richer  in  fusiform 
cells  when  the  blood  was  obtained  from  the  firmly  pressed  or  squeezed 
tail  of  a  specimen  o{  Necturus  than  when  the  blood  was  simply  allowed 
to  drop  on  the  cover  glass  from  the  tail  tip.  Of  course  there  may  be 
other  circumstances  which  serve  to  increase  or  diminish  the  number  of 
fusiform  cells  in  the  preparations,  but  it  seems  reajsonable  to  suppose 
that  the  pressure  which  is  employed  between  two  cover  glasses  to 
rupture  the  red  cells  can  be  as  effectually  exercised  in  the  blood  vessels  of 
the  intact  body.  There  is,  however,  another  factor  which  may  be  less 
extensive  in  its  effects.  I  refer  to  the  giant  cells  in  the  spleen  of  the 
same  animal.  In  a  portion  of  the  spleen  of  a  freshly  killed  Necturus 
teased  out,  a  few  giant  cells  are  always  observable  in  which  one  finds  one 
or  more  large  spherules  of  haemoglobin-holding  substance  imbedded  in 
the  cytoplasma.  These  giant  cells  are  amoeboid,  and  it  is,  presumably, 
reasonable  to  suppose  that  these  masses  of  haemoglobin  have  been 
removed  from  the  discs  of  red  cells  by  the  invaginating  power  of  the 
amceboid  cells.  There  is  in  these  same  cells  no  evidence  whatever  of 
nuclei,  either  chromatolysed  or  intact,  which  could  be  considered  as 
derived  from  the  red  discs,  and  the  only  inference  possible  is  that  the 
nuclei  and  the  remainder  of  the  disc  cytoplasma  have  passed  away  into 
the  general  circulation  as  fusiform  elements.  What  becomes  of  them 
finally  after  they  have  passed  through  the  cycle  of  changes  described, 
whether  the  leucocytes  eat  up  their  disintegrated  remains,  cannot  be 
determined.  I  do  not  know  why  the  nuclei  of  ruptured  red  cells  do  not 
possess  the  same  amount  of  peripherally  disposed  cytoplasma  as  the 
fusiform  corpuscles  do,  but  it  is  supposable  that  either  the  cytoplasma  is 
deposited  from  the  nucleus  or  that  fully  formed  fusiform  cells  are  derived 
from  red  corpuscl^  only  at  a  certain  time  in  the  life  history  of  the  latter, 
and  that  the  conditions  demanded  by  either  of  these  hypotheses  is 
assisted,  in  the  formation  and  transformation  of  the  fusiform  cells,  by  the 
chemical  and  physiological  equilibrium  of  the  blood  inside  the  blood 
vessels. 

We  can  explain  the  fate  of  the  leucocytes.  No  observation  has 
hitherto  been  made  as  to  the  fate  of  the  red  cells.  My  view,  I  think, 
presents  the  easiest  and  best  solution  of  the  question.  With  it  there  is 
no  necessity  for  considering  the  fusiform  elements  as  htematoblasts ;  it  is 
consistent,  furthermore,  with  Strieker's  observations  on  the  transformation 
of  spin41es  into  globular  "white"  cells*  and  it  specially  explains  why 

•  Quoted  by  L6   it,  op.  cit. 


L.   II. 


1890-9 1. J 


AMP'IIBIA    BLOOD   STUDIES. 


7J 


the  fusiform  elements  are  found  only  in  the  blood  of  those  animals  which 
contain  nucleated  red  corpuscles.* 

III.  The  Origin  ov  the  H/Kmatv.>blasts  in  Amphibian  Emurvo. 

There  is  probably  no  biological  subject  on  which  there  is  a  greater 
diversity  of  view  than  that  of  the  origin  of  the  blood  corpuscles  in  the 
embryo  and  adult  vertebrate.  The  views  on  this  point  have  multiplied 
greatly  within  the  last  five  years  and  as  they  have  not  much  in  common, 
a  resumd  of  them  can  hardly  serve  any  useful  purpose  in  a  paper  so 
limited  in  its  scope  as  this  one  is.  The  observations,  nevertheless,  which 
have  been  already  published  as  to  the  origin  of  the  ha^matoblasts  in  Fishes 
.  and  Amphibia  have  an  important  bearing  on  the  facts  which  I  am  about 
to  describe  and  I  shall,  therefore,  give  here  an  outline  sketch  of  them  be- 
fore proceeding  with  the  description  c  f  my  own  observations. 

Goettef  found  the  blood  cells  arise  in  the  mass  of  the  yolk  cells.  On 
the  under  and  lateral  edges  of  the  yolk  mass  in  Batrachian  larva;  blood 
cells  are  formed  by  the  breaking  up  of  the  large  peripheral  yolk  cells  into 
smaller  ones,  and  at  the  same  time  there  separates  from  the  inner  side  of 
the  visceral  layer  a  number  of  cells  forming  a  covering  for  the  groove  in 
the  yolk  in  which  the  blood  cells  are  developed.  As  the  interstitial 
fluidity  of  the  mass  increases  it  extends  over  the  yolk  and  affects 
the  surrounding  tissue  just  in  the  same  manner  as  the  interstitial 
fluid  shapes  the  origin  of  the  primary  vessels,  producing  pouch-like 
diverticula  connected  with  one  another,  from  the  yolk  vessels.  Goette 
regards  the  red  and  white  cells  of  the  spleen  as  direct  descendants  of  the 
yolk  cells. 

DavidoffJ  reservedly  expresses  the  view  that  the  yolk  spherules  give 
origin  by,  possibly,  protoplasmic  transformation  to  parablastic  elements 
and  that  the  latter  develop,  in  many  cases,  into  blood  cells.  On  this  view 
the  nucleus  of  the  blood  cell  is  but  a  yolk  spherule  imbedded  in  a  proto- 
plasmic basis,  and  Davidoff  thinks  that  this  is,  in  a  sense,  a  confirmation 
of  Brass'  theory  that  the  chromatin  of  the  nucleus  of  every  cell  is  secreted 
or  stored  up  food  material. 

*  As  the  red  corpuscle  in  mammalia  is  comparatively  a  fragile  element  its  disintegration  can 
scarcely  involve  the  survival  of  any  formed  or  structural  element.  If  the  fusiform  element  is  the 
nucleus  and  a  small  portion  of  cytoplasma  of  the  red  cell  in  lower  vertebrates,  we  may  suppose 
since  the  platelets  of  mammalian  blood  are  recognised  generally  as  the  homologues  of  the  fusi- 
form cells  that  the  former  are  nuclei  which  have  been  extruded  from  hoematoblasts,  an  extrusion 
which  Rindfleisch  and  Howell  observed. 

t  Entwicklungsgeschichte  der  Unke. 

+  Ueber  die  Entstehung  der  rothen  Blut  Korperchen  und  den  Parablast  von  Salamandra 
maculosa.     Zoologischer  Anzeiger,  1884,  s.  453. 


74 


TRAN8AC!T10N8    OF    THK    CANADIAN    INSTITUTE. 


[Vol.  II. 


I 


Wenckebach*  found  that  in  Telcost  enibryo.s  the  blood  cells  originate 
from  a  mass  of  cells  placed  under  the  notochord  and  between  it  and  the 
hypoblastic  layer.  The  origin  of  this  cell  mass  could  not  be  determined, 
when  he  published  his  first  paper,  but  afterwards  he  traced  it  to  the 
mcsoblast  and  was  able,  therefore,  to  corroborate  Ziegler'.sf  first  observa- 
tions on  this  point.  This  intermediate  cell  mass  may  arise,  as  in  Be/one, 
from  an  impaired  organ  but  in  the  Salmon  it  is  formed  by  the  fusion  of 
two  separate  columns  of  cells.  The  blood  cells  arc  thus,  according  to 
Wenckebach,  of  mcsoblastic  origin  and  are  not  derivable  in  any  way 
from  the  hypoblast  or  from  the  periblastic  cells. 

Ziegler*  confirms  Wenckebach's  observations  on  the  development  of 
the  blood  cells  in  the  majority  of  Teleost  embryos  out  of  the  cellular 
elements  of  the  intermediate  cell  mass  placed  between  the  entoderm 
and  chorda.  This  mass  is  of  mesodermal  origin  and  the  cells  con- 
stituting it  wander  away  over  the  yolk  and,  in  a  measure,  as  they  do  this 
they  make  the  cavities  previously  occupied  by  them  larger  and  larger, 
the  cavities  forming,  finally,  the  cardinal  veins.  Up  to  this  time  the 
blood  which  is  free  from  cellular  elements,  flows  in  closed  vessels 
represented  at  this  stage  by  the  heart,  aorta,  caudal  vein  and  sub- 
intestinal  veins.  The  latter  empty  on  the  yolk  and  the  blood  passes 
from  the  posterior  surface  of  the  yolk  sack  to  the  heart,  not  in 
a  closed  vessel,  but  free  in  the  space  between  the  yolk  and  the  ectoderm. 
There  arises  in  the  yolk  a  corresponding  furrow  to  which  wandering 
cells  pass  to  form  a  vascular  wall.  These  wandering  cells  are  in  no  way 
distinguishable  from  the  blood  corpuscles  of  the  same  stage  which  are 
abundant  on  the  surface  of  the  yolk  and  which  arise,  as  already  said, 
from  the  elements  of  the  intermediate  cell  mass.  Sometimes,  as  in 
the  pike,  a  formation  of  blood  cells,  similar  to  that  occurring  in  the 
intermediate  cell  mass,  obtains  in  a  portion  of  the  aorta. 

According  to  this  view  the  blood  cells  are  derived  from  the  columns 
of  cells  which  occupy  the  position  of  the  developing  cardinal  and  other 
veins  and  they  are  not,  except  accidentally,  and  through  their  amoeboid 
movement,  connected  with  the  yolk. 

*  The  development  of  the  blood  corpuscles  in  the  Embryo  of  Perca  fluviatilis.  Jour,  of 
Anat.  .ind  Phys.  Vol.  XIX.,  1885,  p.  231.  Also  :  Beitriige  zur  Enlwicklungsgeschichte  der 
Knochenfische.     Arch,  fiir  Mikr.  Anat,,  Bd.  XXVIII,  p.  225. 

*  Die  Enibryonale  Entwicklung  von  Salmo  Salar.    (Inaugural  Dissertation).    Freiburg,  1882. 

*  Die  Entstehung  des  Blutes  bei  Knochenfischembryonen.  Arch,  fur  Mikr.  Anat.,  Bd. 
XXX,  s.  596.  Also  :  Die  Entstehung  des  Blutes  der  Wirbelthiere.  Berichte  d.  Naturforsch. 
Gesell.  zu  Freiburg  i.  B.    Bd.  IV.  s.  171. 


i 


L.  II. 


18J0-91.] 


AMPHIBIA    BLOOD   HTUDIEH. 


70 


nate 
the 
ncd, 
the 
rva- 
lone, 
)n  of 
g  to 
way 


Ruckert*  gives  a  full  description  of  the  origin  of  the  blood  cells  in 
Torpedo  embryos.  He  found  them  to  arise  in  the  peripheral  mcsoblast 
where  they  constitute  groups  situated  in  cavities  formed  between  the 
spindle-shaped  incsoblastic  cells.  Where  the  outer  and  inner  layers  of 
the  bl.istoderm  arc  closely  applied  to  the  yolk  these  groups  give  off  cells 
which  constitute  the  blood  islands  of  the  posterior  germinal  area.  At  the 
latter  point,  according  to  RUckert,  there  can  be  no  doubt  about  the  origin 
of  the  blood  cells  out  of  the  mesoblast.  Laterally,  and  in  front  where 
the  mesoblast  is  thin,  the  formation  of  the  blood  and  of  the  vessels  occurs 
through  the  accession  to  this  part  of  freshly  divided  yolk  cells  (mcrocytcs). 
Far  anteriorly,  the  merocytes  may  be  very  large  in  size  and  appear  then 
as  niegasphcres.  The  latter  may,  through  unequal,  imiircct  division,  bud- 
ding and  fragmentation,  give  also  origin  to  blood   cells  and  mesoblast. 

This  brief  sketch  of  the  various  theories  as  to  the  method  of  blood 
formation  and  the  origin  of  blijod  cells  shows  how  discordant  they  are. 
Goette  believes  that  the  peripheral  yolk  cells  break  up  into  h.tmatoblasts, 
Davidoff  thinks  that  yolk  spherules  become  the  nuclei  of  the  red  cells 
and  that  the  discoplasma  is  ^Icrived  from  transformed  protoplasm  of 
the  yolk,  Wenckebach  and  Zieglcr  considered  that  the  h;ematoblasts  are 
of  mesoblastic  origin  wholly,  while  Riickert  is  apparently  disposed  to 
believe  that  they  are  derived  from  the  yolk  cells  on  the  one  hand  and 
from  the  mesoblast  on  the  other. 

As  far  as  my  observations  on  the  Amblystoina  larva;  go  they  are  in 
accord  with  those  of  Wenckebach  and  Ziegler  on  Telcostean  embryos,  as 
to  the  derivation  of  the  hcxmatoblasts  from  the  mesoblast  alone. 

The  first  blood  corpuscles  of  the  Amhlystoma  larva;  appear  at  about 
the  twelfth  or  thirteenth  dayf  after  the  deposition  of  the  ova.  At  this 
date  the  heart  is  in  the  process  of  formation,  the  endothelial  portions 
of  it  being  derived  from  the  entoblast  in  the  manner  described  by 
Rabl*  for  Salainandra  and  Triton.  The  heart  cavity,  for  thirty-six  hours 
after  this,  even  when  fully  formed,  contains  no  cellular  elements  of  any 
sort.  The  first  blood  vessels  to  be  formed  appear  also  at  the  twelfth  day, 
constituting  the  subintestinal  veins§  and  it  is  in  association  with  the 
formation  of  these  that  the  ha;matoblasts  make  their  appearance. 

*  Ueber  die  Anla|,'e  des  mittleren  Kiemblattes  und  die  erste  Hliubildung  bei  Torpedo. 
Anal.  Anz.,  1887,  Nos.  4  and  6.  Also  :  Weitere  Beitrage  zur  Keimblatlbildung  l)ci  Sclachiern. 
Anat.  Anz.,  1889,  No.  12. 

+  These  dates  are  only  approximate  as  there  is  a  great  variation  in  the  development  of  the 
larviB  in  the  same  mass  of  eggs. 

iMorph.  Jahrbuch,  Ikl.  XII.  p.  252. 

§The  occurrence  of  two  subintestinal  veins  .instead  of  one  in  Sclachii  was  first  pointed  out 
l)y  Mayer  (Mitth.  ans  des  Zool.  .Stat,  zu  Ncapel,  Vol.  VII.,  p,  340)  and  subsequently  by  Riickert 
('.V.  ,-/'.! 


76 


THANSAC'XIONB   OF    THE   CANADIAN    INSTITUTE. 


[Vol.  II. 


.M 


i 


I 


At  about  the  eleventh  day  the  ventral  portion  of  the  mesoblastic  plate 
on  each  .side  consists  of  two  layers  of  cells  forming  the  visceral  and 
parietal  portion  of  the  plate.  These  layers  are  closely  applied  to  the 
entoblast  and  ectoblast  respectively,  but  not  at  first  to  each  other,  for 
evidences  of  a  slit-like  space  between  them  which  represents  a  persistent 
part  of  the  primitive  body  cavity,  can  be  very  well  seen  at  this 
date.  This  slit  quickly  disappears  through  the  growth  of  the  adjacent 
parts  and  the  consequent  pressure  exercised  on  the  mesoblastic  cells. 
The  latter  are,  at  first,  more  or  les--  rounded  in  outline  but  the  pressure 
exerted  on  them  gives  them  a  somewhat  flattened  appearance,  except  at 
the  lower,  extreme  margin  where  the  visceral  and  parietal  layers  become 
connected,  the  cells  of  the  visceral  layer  here  retaining,  to  a  considerable 
extent,  their  original  shape. 

This  part  of  the  mesoblast  seems  to  possess  a  greater  capacity  for 
proliferation  than  the  more  dorsally  placed  portions  of  the  ventral  half. 
The  proliferation  is  limited  chiefly  to  the  cells  at  the  extremity  of  the 
plate  and  to  those  immediately  above  this  belonging  to  the  visceral 
layer.  The  latter  at  the  point  in  question  is,  about  the  twelfth  day, 
formed  of  two  or  more  series  of  cells,  those  constituting  the  rriost 
internal  layer  becoming  very  much  flattened  and  like,  in  this  respect,  the 
cells  of  the  single  layer  of  the  parietal  portion.  The  cells  placed 
between  are  obviously  in  the  position  occupied  previously  by  the  slit- 
like space,  the  more  ventrally  placed  portion  of  the  primary  body  cavity, 
and  as  they  undergo  division  more  frequently  than  the  other  cells,  they 
cause  a  still  greater  flattening  of  the  remaining  cells  of  the  visceral  layer 
and  of  those  of  the  parietal  portion,  with  the  result  that  these  resemble 
fully  formed  endothelial  cells.  In  a  transverse  section  of  the  larva  at  about 
the  thirteenth  day,  taken  a  short  distance  behind  the  developing  heart, 
the  cells  first  described  lie  in  two  large  masses  one  on  each  of  the  ventro- 
lateral margins  of  the  entoblast  in  which  depressions  exist  to  contain 
the  masses  of  cells.  The  depressions  are  lined  by  the  flattened  endothe- 
lial elements  derived  from  the  visceral  layer  which  are  now  recognisable 
with  difficulty,  and  covered  externally  by  similarly  flattened  endothelial 
cells  derived  from  the  parietal  layer.  The  visceral  and  parietal  layers 
above  this  are  still  at  this  time  formed  each  of  only  one  layer  of  ceils 
more  or  less  flattened.  The  cells  constituting  the  masses  described  are 
the  hsmatoblasts,  while  the  depressions  in  the  yolk  or  entoblast  consti- 
tute the  site  of  the  subintestinal  veins. 

As  the  subintestinal  veins  are  followed  backwards  they  are  seen  to  ap- 
proach, with  the  mesoblast  plates,  more  and  more  the  middle  of  the  line 
of  the  ventral  side  of  the  yolk  and  where  the  mesoblastic  plates  from 


1890-91.1 


AMPHIBIA    BLOOD   STUDIRS. 


73 


each  side  unite  in  the  middle  line,  the  veins  form  a  single  channel, 
till  a  point  immediately  in  front  of  the  anus  is  reached.  In  its 
course  backwards  the  vessel  is  filled  with  cells  closely  packed  and  derived, 
in  the  same  manner  as  those  forward  arc,  from  the  viscer.il  layer  of  the 
mesoblast,  although  it  is  more  difficult  to  exclude  here  the  participation 
of  the  parietal  layer  in  the  formation  of  the  h.x-matoblasts.  The  nieso- 
blastic  plates  again  diverge  at  the  anus  and  the  venous  trunk  bifurcates. 
a  branch  running  separately  on  e.ich  side  of  the  cloacal  cavity,  the  cells 
contained  in  them  becoming  less  in  number  till,  for  lack  of  them,  it  is  im 
possible  to  follow  the  veins  any  distance  behind  the  anus. 

When  these  veins  and  the  cellular  elements  in  them  have  attained  the 
development  described  the  heart  is  formed  and  beats.  At  first  it  contains 
no  organized  elements,  the  force  of  the  beat  being,  apparently,  exercised 
on  what  would  appear  to  be  serum.  About  the  fifteenth  or  sixteenth  day 
cellular  elements  in  every  respect  like  those  found  in  the  subintestinal 
veins  are  found  in  large  numbers  in  the  heart  cavity  and  as  the 
subintestinal  veins  are  almost  empty  it  is  clear  that  the  haimatoblasts 
are  derived  from  this  source.  It  i.s,  in  fact,  easy  in  scries  of  sagittal 
sections  of  larvae  of  the  fourteenth  and  fifteenth  days  to  see  the  detach- 
ment of  the  hjEmatoblasts  in  the  anterior  portions  of  the  subintestinal 
veins  and  their  arrival  in  the  heart  cavity. 

The  haematoblasts  are  derived  from  this  source  alone.  All  the  other 
vessels  of  the  body  have  a  different  origin,  that  is,  they  are  not  formed  by 
solid  columns  of  cells  exerting  a  pressure  on  the  immediately  adjacent 
mesoblastic  elements,  but  rather  by  the  extension  of  the  subintestinal 
vessels  and  of  the  cavities  of  the  heart.  In  Amblystoma  larvae  therefore 
the  haematoblasts  are  of  mesoblastic  origin  alone  and  they  are  not  in- 
creased in  numbers  by  additions  from  the  yolk  elements  or  entoblast. 

At  first  they  are  large,  not  differing  from  mesoblast  cells  in  any- 
thing except  their  somewhat  spherical  shape.  They  contain  in  their 
cytoplasma  a  large  number  of  yolk  spherules  which  obscure  more  or  less 
the  nucleus.  The  latter  is  somewhat  irregular,  often  amoeboid  in  outline 
and  richer,  apparently,  in  chromatin  than  the  ordinary  mesoblastic  cells 
of  the  same  stage  of  development.  To  this  greater  richness  in  chromatin 
may  be  attributed  the  more  abundant  proliferation  of  these  cells,  for  one 
can  see  that  cell  division  is  more  frequent  in  them  than  in  the  neigh- 
boring cells.  As  the  quantity  of  yolk  spherules  is  limited,  the  repeated 
division,  probably  accompanied  by  a  digestive  action  on  the  part  of  the 
cell  on  the  spherules,  produces  a  form  of  haematoblast  (Fig.  i6  and  17 
a  and  b)  in  which  the  yolk  spherules  are  few  and  in  which  nuclear 
chromatin  is  very  abundant.      It   is   in   this   stage   that  one  finds  the 


74 


TKANHAimoNB    Of  THK   CANADIAN    INSTITUTE. 


[Vol.  II. 


h.T:matobIast  amnnboid  in  outlines.  Its  cytoplasma  is  as  yet  undiffer- 
entiated and  it  docs  not  possess  a  membrane  althouf,'h  the  peripheral 
portion  {TJves  evidence  of  its  forniatic^n  in  tlic  presence  of  a  scries  of 
rcffularly  arranjjcd  granulc-lii<e  bodies  affording  a  sliarply  outlined 
border. 

In  Figs.  19,  20  and  21  we  see  the  ha;inatoblasts  of  a  later  stage 
with  much  fewer  yolk  spherules  and  with  specialization  of  form  and 
structure  allied  to  that  in  tlie  mature  red  corpuscle.  The  outline 
is  o/al  or  elliptical  and  the  peripheral  portion  is  usually  limited 
by  d  clear  hyaline,  somewhat  thick  membrane  while  the  cytoplasma  is 
differentiated  into  coarse  or  fine  trabeculie  strewn  along  which  are 
granules,  some  of  them  brownish  in  color  like  those  found  occurring  in 
the  mc';oblastic  and  cctoblastic  cells  of  this  and  later  stages.  Frequently 
the  cytoplasma  in  the  immediate  vicmity  of  tiie  nucleus  is  den.ser,  stains 
somewhat  more  deeply  than  the  remainder  while  it  sends  coarse  pro- 
oii^ations  in  a  ra  li.itinij  fasliio;i  outwirJs  (Fig.  20).  The  corpuscles  are 
not  as  yet  flattened,  but  about  the  twentieth  day  the  majority  of  them 
are  elliptical  in  outline  and  fl.ittened.  When  the  larviu  of  this  date  are 
fi.xed  with  Flemming's  Fluid  the  discoplasma  and  nuclei  of  such 
blood  cells  are  homogeneous,  indicating  that  the  latter  arc  fully  formed^ 
or  mature  blood  cells.  These  corpuscles  are  no  longer  capable  of  division 
and  their  nuclei  give  with  alum  crchineal  a  reddish-brown  stain  and  vVith 
haematoxylin  a  brown  stain,  in  .-ach  case  like  that  given  in  the  red  cor- 
puscles of  the  adult  animal.  There  still  persist  ha;matoblasts  in  which 
karyokinesis  is  very  common  and  in  which  no  specialisation  of  forT,,' 
such  as  that  described  for  the  remaining  blood  cells,  is  observable.  These 
are  the  elements  from  which  originate,  not  only  the  future  blood  cor- 
puscles, but  al.so  the  future  haematoblasts.  These  elements  form  but  a 
small  proportion  of  the  whole  number  of  corpuscles  and  as  they 
pos.sess  the  power  of  division  while  the  mature  elements  do  not,  the 
origin  of  these  must  now  be  considered. 

In  order  to  determine  this,  sections  of  larvjE  of  the  eighteenth  and  nine- 
teenth days  hardened  in  chromic  acid  and  stained  with  haematoxylin  and 
eosin  must  be  examined.  If  a  section  through  the  sinus  venosus  be 
under  observation  it  v/ill  be  found  that  that  cavity  contains  a  large 
number  of  blood  corpuscles  which,  according  to  the  staining  effects  of  the 
two  dyes,  can  be  divided  into  two  classes:  one,  the  more  numerous  in 
which  both  nucleus  and  cytoplasma  show  a  special  affinity  for  the  eosin, 
the  former  being  often  stained  only  with  this  dye;  the  other,  comprising 
corpuscles  in  the  nuclei  of  which  the  haematoxylin  alone  has  reacted. 
Both  classes  of  corpuscles  are  fairly  represented  in  Fig.  15,  a  and  b,  the 


II. 


1890-91.] 


AuriiiniA  ntooD  btudiks. 


7.> 


greenish  elements  of  the  cytoplasma  in  both  beiny  yolk  splieruks  coloreil 
by  the  reduction  of  the  chromic  acid.  In  the  corpuscles  at  tins  st.i^c 
karyokincsis  is  not  more  common  than  it  is  in  ordinary  tissue  cells.  It 
would  appear  that  tiie  more  numerous  class  of  ct)rpusclcs,  /'.  «•.,  those 
reactin^j  deeply  with  eosin,  become  converted  into  the  mature  blood  cells 
existing  in  the  larva  up  to  the  twenty-fifth  day,  for  it  is  these  cells  onl)- 
which  illustrate  the  specialization  of  form  and  structure  already  described 
and  partly  represented  by  Vh^s.  19-21.  The  cells  which  react  with 
hitmatoxylin  alone  constitute  the  persistent  elements  which  ultimately 
become  the  ficcjuently  dividin;^  h.x-matoblasts  of  the  later  staj^es  of  de- 
velopment. The  cosinophilous  cells  are  api)arently  in  a  condition  of 
degeneration,  for  the  division  of  their  nuclei  is  not  always  followed  by  a 
division  of  the  cell  (Fi^^  iH).  Hoth  cla.sses  of  h.eniatoblasts  at  this  time 
do  not  specially  illustrate  division  but  those  which  stain  with  hiema- 
toxylin  only  .seem  to  retain  the  capacity  for  proliferation  while  the 
cosinophilous  elements  gradually  lose  it  within  the  next  ten  days. 

At  a  period  which  seems  to  comcide  with  the  formation  of  the  liver  as 
a  vascular  organ  and  with  the  development  of  tubules  in  it,  ihe  ha;mato- 
blasts,  which,  from  the  sixteenth  to  the  nineteenth  day,  when  hardened  in 
chromic  acid,  stain  with  ha;matoxylin  only,  now  begin  to  acc^uire  a  capa- 
city for  proliferation  far  in  excess  of  that  which  they  previously  had.  It 
would  appear  that  this  change  is  associated  with  the  appearance,  in  the 
blood  vessels  of  the  body  generally  and  of  the  liver  specially,  of  a  serum 
which  stains  very  deeply  with  eosin.  This  serum  stains  slightly  with 
alum-cochineal  but  greenish-blue  or  green,  like  the  yolk  spherules,  with 
the  Indigo-carmine  Fluid  described  in  the  foregoing  pages.  I  regard  this 
staining  capacity  of  the  serum  as  due  to  the  solution  of  yolk  or  rather  of 
that  constituent  of  it  which  has  been  called  haematogen  by  Bunge.  This 
is  but  a  reserve  form  of  chromatin  and  as  the  undifferentiated  haima- 
toblasts  float  in  the  serum,  it  is  reasonable  to  believe  that  they  absorb  the 
dissolved  chromatin.  It  is  from  this  time  on  that  the  ha;matoblasts  begin 
to  manifest  the  incessant  divisions  which  characterize  the  stage  repre- 
sented by  Figs.  9,  10  and  1 1.  It  is  at  this  time  also  that  the  chromatic 
figures  of  the  haematoblasts  increase  in  size.  Previously  their  figures  were 
not  larger  than  those  of  the  other  cells  of  the  body.  These  facts  can  be 
explained  in  no  other  way  than  by  assuming  that  the  haematoblasts  sur- 
viving as  such,  absorb  the  chromatin  or  "  haematogen  "  which  is  dissolved 
in  the  serum  and  thereby  entered  on  a  phase  of  renewed  vitality.  The 
other  cells  in  the  body  also  exhibit  divisions  now  more  frequently  than 
before  this  stage,  though  not  by  any  means  as  frequently  as  the  haemato- 
blasts, and  this  increased  capacity  for  proliferation  may  also  be  explained 


76 


TRANSACTIONS   OF   THE    CANADIAN    INSTITUTE. 


[Vol.  II. 


I 


II' 


by  the  more  abundant  supply  of  dissolved  chromatin  in  the  serum  bath- 
ing them. 

These  haematoblasts  are  met  with  most  frequently  in  those  parts  of 
the  circulatory  apparatus  where  the  blood  current  is  slow  or  where  physical 
conditions  retard  their  movement.  Such  conditions  are  found  between 
the  muscle  trabecule  stretching  through  the  heart  cavity  after  these  are 
formed,  in  the  concave  portions  of  the  aortic  arches  and  especially  in  a 
minute  branch  of  the  arteria  mesenterica  distributed  in  a  plate  of  tissue 
derived  from  the  visceral  layer  of  the  mesoblast.  This  is  the  site  for  the 
future  spleen.  The  origin  of  the  spleen  in  the  visceral  layer  of  the 
mesoblast  in  the  toad  was  pointed  out  by  Goette*  who  described  the 
cells  of  the  organ  as  direct  descendants  of  the  yolk  cells  (entoblastic 
cells).  My  observations  are  not  yet  concluded  in  the  development  of  the 
spleen,  but  they  have  progressed  so  far  as  to  allow  me  to  say  definitely 
that  the  organ  increases  in  bulk  by  multiplication  of  the  capillaries 
arising  from  the  branch  of  the  mesenteric  artery  to  accommodate  the 
excessively  large  number  of  haematoblasts  derived  by  division  from  the 
original  haematoblasts  which  have  been  caught  in  the  narrow  spaces  of 
the  capillaries,  early  in  development  of  the  organ.  At  a  date  roughly 
corresponding  to  the  interval  between  the  fortieth  and  sixtieth  days,  sec-^ 
tions  of  the  organ  fixed  in  Flemming's  Fluid  and  stained  with  haematoxr 
ylin  and  eosin,  contain  a  very  great  number  of  elements  like  those  repre- 
sented in  Figs.  lo  and  ii.  In  fact  sections  of  the  organ  thus  prepared 
have  a  deep  ochre-red  or  terra-cotta-red  color,  owing  to  the  great  number 
of  mitotic  haematoblasts  present  in  it.  At  later  stages  of  development 
haematoblasts  are  rarely  found  elsewhere  than  in  the  spleen,  which  is,  from 
now  on,  the  organ  for  their  production  out  of  the  original  elements  whose 
history  has  been  traced  above  and  whose  presence  in  the  spleen  is  to 
be  explained  as  I  have  pointed  out.  Whether  there  is  a  secondary 
formation  of  haematoblasts  -out  of  the  cells  of  the  original  tissue  of  the 
visceral  layer  of  the  mesoblast,  it  is  impossible  to  say,  but  as  the 
haematoblasts  and  the  spleen  are  both  formed  cut  of  portions  of  visceral 
layer,  such  a  secondary  origin  is  not,  theoretically,  improbable.  All  that 
I  can  at  present  say  is  that  early  in  the  development  of  the  spleen  its 
vascular  channels  become  distended  with  haematoblasts,  which  are  also  to 
be  found  in  other  vessels  of  the  body  where  the  blood  current  is  slowed 
or  retarded,  that  these  haematoblasts  undergo  rapid  divisions  and  in- 
creaoe  thereby  the  size  of  the  organ  and  that  these  divisions  are  quite 
sufficient  to  explain  the  occurrence  there  of  all  the  haematoblasts 
observed.     The  first  appearance  of  the  organ   in  fact  consists  in  the 

•  Loc.  cit.  p.  8 1 3. 


\. 


1890-91.] 


AMPHIBIA    BLOOD    81UDIES. 


77 


presence  of  a  few  haematoblasts  like   those  shown    in  Figs.   lo  and  t  i 
in  the  channel  of  the  branch  of  the  mesenteric  artery. 

As  I  have  never  found  in  adult  caudate  Amphibia  haematoblasts  in  any 
other  organ  than  the  spleen  and  then  only  in  its  blood  sinuses,  these 
may  be  regarded  as  direct  descendants  of  the  hiematoblasts  which  arise 
by  proliferation  of  the  cells  of  the  ventral  portion  of  the  visceral 
plate  of  the  mesoblast. 

It  is,  I  think,  worthy  of  note  that  though  there  is  but  one  source  for 
all  haematoblasts,  yet  there  are  two  stages  in  their  history,  the  second  of 
which  appears  when  the  liver  begins  to  take  on  its  adult  structure,  the 
forms  belonging  to  this  stage  being  remarkable  for  their  great  capacity 
for  division,  while  the  first  series  of  haematoblasts  are,  almost  wholly, 
formed  in  the  subintestinal  veins  and  the  great  majority  of  them 
are  directly  converted  into  red  cells,  the  remainder  persisting  to  form  the 
haematoblasts  of  the  second  stage. 

IV.  Conclusions. 

1.  The  haemoglobin  of  the  blood  corpuscles  is  derived  from  the  abun- 
dant nuclear  chromatin  of  the  hasmatoblast. 

2.  The  fusiform  cells  of  Amphibian  blood  are  derived  from  the  red 
corpuscles,  the  latter  in  this  conversion  losing  the  cell  membrane  and  the 
greater  portion  of  the  discoplasma. 

3.  The  haematoblasts  in  Ambly stoma  are  direct  descendants  of  cells 
split  off  from  the  extreme  ventral  portions  of  the  visceral  mesoblast  and 
they  pass,  at  first,  a  portion  of  their  existence  in  a  specialized  part 
of  the  original  body  cavity  of  the  embryo. 

V.  Appendix.* 

The  foregoing  paper  was  written,  part  in  1889,  part  in  1890.  The 
publication  of  it  now  seems  opportune  since  one  of  the  conclusions  con- 
tained in  it  has  been  fully  confirmed  by  the  results  of  my  investigations 
during  the  last  year.  The  chromatin  of  every  cell,  animal  and  vegetable,  is 
an  iron  compound  and  this  can  be  proved  not  only  by  the  use  of  freshly 
prepared  ammonium  sulphide,  as  described  in  a  communication  sent  to 
the  Royal  Society  of  London f  last  year,  but  also  by  other  methods  since 
discovered,  the  use  of  which  excludes  inorganic  and  albuminate  iron  and, 
at  the  same  time,  does  not  affect  the  iron  in  haemoglobin  or  haematin. 
With  the  more  recently  discovered  methods,  so  easy  is  their  application 

*  Written  Feb.  4,  1892. 

t  Proceedings,  Toy.  Soc,  Vol.  50,  p.  277. 


78 


TRANSACTIONS    OF    THE    CANADIAN    INSTITUTE. 


[Vol.  II. 


and  so  definite  their  reaction,  one  may  make  permanently  mounted  pre- 
parations of  sections  of  animal  and  vegetable  tissues,  in  which  the  distribu- 
tion of  the  chromatin  is  shown  by  the  iron  reaction.  The  latter  may 
thus  be  quite  readily  employed  instead  of  the  staining  methods  with  haima- 
toxylin  and  other  dyes  which,  when  carefully  used,  are  supposed  to  select 
only  chromatin.  The  results  which  I  have  obtained  with  the  new 
methods  are  so  numerous  and  so  important  that  I  must  reserve  an  ex- 
tended description  of  them  for  another  paper.  Suffice  it  at  present  to  soy 
that  the  fundamental  life  substance  is  an  iron  cofitpound  and  that,  in;-  ren 
tially,  the  chemical  processes  underlying  life,  in  other  xvords  life  itsclj  ]  n\- 
to  be  referred  to  the  constant  oxidation  and  reduction  of  the  iron  of  this 
compound.  This  iron-holding  compound  being  present  in  every  living 
cell,  the  mystery  of  the  appearance,  here  and  there  in  animal  and  veget- 
able forms,  of  haematin*  either  free,  or  att  iched  to  a  proteid  as  haimo- 
globin,  is  explained. 

It  is  to  be  noted  further  that  the  iron,  though  not  held  in  chromatin 
as  firmly  as  it  is  in  haematin,  is  yet  as  tenaciously  held  therein  as  it  is  in 
the  ferrocyanides,  which  also  yield,  under  the  same  conditions,  their 
iron  to  ammonium  sulphide. 

The  methods  referred  to  show  further  that  the  stainable  substance 
which  diffuses  from  the  nuclei  and  mitotic  figures  in  hajmatoblasts,  is  an 
iron  compound  in  which  the  iron  is  less  firmly  held  than  in  haemoglobin, 
and  that  it  persists  for  comparatively  a  long  time  as  such,  before 
becoming  converted  into  the  latter  substance.  There  are  also  facts  which 
seem  to  indicate  that  haemoglobin  is  a  degeneration  product  and  not  a 
substance  formed  in  the  synthetical  processes  of  the  haematoblasts. 

The  bearing  of  these  conclusions  on  the  currently  accepted  views 
as  to  the  pathology  of  anaemia  is  obvious.  Since  haemoglobin  is  a 
derivative  product  of  chromatin,  and  since  the  latter  is  an  iron  compound 
all  important  in  cellular  life,  anaemia  cannot  be,  primarily,  a  deficiency  in 
the  formation  of  haemoglobin,  but,  first  of  all,  a  deficiency  in  chromatin, 
not  only  of  haematoblasts,  but  of  every  cell  in  the  body.  In  other  words 
the  primary  cause  of  all  anaemias,  other  than  haemolytic,  is  hypochromatosis 
and  the  condition  wh'ch  Virchow  called  hypoplasia  is  as  much  a  result  of 
this  hypochromatosis,  as  is  the  deficiency  in  formation  of  hremoglobin. 

Other  points  arising  out  of  these  investigations  may  be  mentioned :  the 
differences  between  animal  and  vegetable  chromatin  and  between  the 
chromatin  of  highly  specialized  animal  cells  on  the  one  hand  and  that  of 
lower  forms  of  animal  life,  on  the  other,  the  occurrence  of  haemoglobin 


*Linossier  and  Phipson  describe  (Comptes   Rendus  Vol.   CXII,  pp.    40 
occurrence  of  hiematin-like  compounds  in  Aspergillus  niger  and  Palmella  cruew 


:  ^  666)  the 


'k    i 


1890-91.] 


AMPHIBIA    BLOOD    8T0DIE8. 


79 


chiefly  in  the  higher  types  of  animal  life,  the  analogies  between  chloro- 
phyll and  hxmatin  and  the  derivation  of  the  digestive  ferments  from 
chromatin. 

These  and  other  related  subjects  I  intend  to  discuss  in  a  future  publication. 


EXPLANATION  OF  FIGURES. 

Figs.  1-4  are  drawn  from  preparations  from  the  adult  Necturus,  and  Figs.  5-7  are 
taken  from  larval  Amblystomata  (A.  punctatum). 

Fig.  I.  Red  disc  from  a  cover-glass  preparation  of  the  blood.    Corrosive  sublimate, 
IndiRo-carmine  Fluid— X  700. 

Fig.  2.   Red  disc  from  splenic  vein.    Chromic  acid.  Indigo-carmine  Fluid — X7oo- 

Fig.  3.   Red  disc,  cover-glass  preparation.    Chromic  acid,  Hematoxylin,  Eosin — X 
700. 

Fig.  4.  Red  disc  cover  preparation.   Corrosive  sublimate,  Haematoxylin,  Eosin  —  X  7oo. 

Fig.  5.  Red  disc  from  heart  cavity.  Flemming's  Fluid,  Haematoxylin,  Eosin— X  1,000. 

Fig.  6.  Red  disc  from  gill  vessel.     Osmic  acid,  Hasmatoxylin,  Eosin— X  1,000. 

Fig.  7.  Cover-glass  preparation  of  red  blood  cells.     Fresh,  acetic  methyl-green — X 
1,000. 

Fig.  8.  Group  of  blood  cells  from  a  vascular  sinus  in  a  section  of  the  spleen  of 
Necturus.  In  the  centre  is  represented  a  haematoblast  in  mitosis  and  with  its  chro- 
matin so  changed  chemically  that  it  takes  the  sulphindigotate  portion  of  the  reagent  ; 
a,  a  red  disc,  b  a  leucocyte.     Chromic  acid,  Indigo-carmine  Fluid — X700. 

Fig.  9.  From  a  free  swimming  Amblystoma  larva. 

a,  Haematoblast  from  the  concave  side  of  one  of  the  aortic  arches,  in  division  u 
showing  in  the  abundant  chromatin  as  well  as  in  the  cytoplasma  a  slate  or  slate-brown 
reaction. 

b,  an  endothelial  cell  from  same  aortic  arch  in  same  preparation  undergoing  mitosis 
and  showing  the  normal  reaction  of  the  staining  fluid. 

Flemming's  Fluid,  Haematoxylin —  X 1000. 

Fig.  10.  Haematoblast  from  concave  side  of  aortic  arch  in  a  free-swimming  larval 
Amblystoma.     Flemming's  Huid,  Haematoxylin,  Eosin — X  1,000. 

Fig.  II.  Haematoblast  from  same  preparation  as  last — X  1,000. 

Fig.  12.  A  dividing  haematoblast  in  the  last  stage  of  its  development,  showing  two 
kinds  of  chromatin  in  the  nuclear  figures.  Cover-glass  preparation.  Corrosive  subli- 
mate, Haematoxylin,  Kosin —  X  1 ,000 

Figs.  13-14.  Haematoblasts  in  the  last  stage  of  their  development,  showing  a  de- 
generated chromatin  between  the  regular  chromatin  loops  of  the  dividing  nuclei. 
From  the  heart  cavity  of  a  free  swimming  Amblystoma  larva.  Flemming's  Fluid, 
Hematoxylin,  Eosin— X  1.000. 


80 


TRANSACTIONS   OF   THE   CANADIAN    INSTITUTE. 


[Vol.  II. 


if   {•: 


Fig.  1$,  a  and  b.  Two  ha?matoblasts  from  the  heart  cavity  of  a  very  young  Ambly- 
stoma  larva  (not  free  swimming).     Chromic  acid,  Hematoxylin,  Eosin.     x  1250. 

Figs.  16  and  17,  a  and  b.  Amoebiform  hsematoblasts  from  heart  cavity  of  a  very 
young  larva  (not  free  from  envelope).  The  chromatin  is  very  dense  in  the  nuclei. 
The  cavities  in  the  cytoplasma  were  occupied  by  yolk  spherules. 

Flemming's  Fluid,  Alum-cochineal — X900. 

Figs.  18  and  19.  Two  haematoblasts  from  the  heart  cavity  of  very  young  larva  (not 
free  swimming).  Cavities  in  cytoplasma  occupied  by  yolk  spherules.  Fig.  19  repre- 
sents a  more  fully  developed  corpuscle  with  well  defined  contour  and  abundant 
chromatin.     Chromic  acid,  Haematoxylin,  Eosin — X1250. 

Fig.  20,  a  and  b.  Two  hrematoblasts,  from  a  very  young  larval  Amblystoma,  with 
definite  elliptical  outlines,  uncolored  cytoplasma  and  the  nuclei  abundantly  provided 
with  chromatin.     Chromic  acid,  Haematoxylin,  Eosin — X900. 

Fig.  21,  a  and  b.  Two  htematoblasts  from  larva  of  same  age  as  in  last  case.  P'lem- 
ming's  Fluid,  Alum-cochineal — X1200. 

Fig.  22,  a--f.  DifTerent  forms  of  fusiform  corpuscles  met  with  in  the  same  cover- 
glass  preparation  of  Necturus'  blood, — b  was  fixed  while  exhibiting,  apparently,  the 
slow  vibratory  motion  of  its  thorn-like  prolongations.  Corrosive  sublimate,  Haema- 
toxylin, Kosin — X  1,000. 

Fig.  23,  a—d.  Fusiform  corpuscles  of  Neduru^  blood  exhibiting  various  intra 
nuclear  arrangements  of  its  chromatin.     Cover  preparation.  Picric  acid,  Safranin. 

Fig.  24,  a  and  b.  A  haematoblast  (?)  seen  at  two  different  optical  planes  exhibiting, 
the  peculiar  yellowish   granules  (h.Tsmoglobin?)  apparently  like  those  described  b^  , 
Cuenot  as  secreted   from  the  nucleus— a,  at   the  plane  passing  through  the  upper 
surface  of  the  nucleus,  b,  at  the  plane  passing  the  centre  of  the  nucleus.    There  is  very 
little  cytoplasma  in  this  cell.     Fresh — xiooo. 


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