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aN
JOURN AL
OF THE
ROYAL
MICROSCOPICAL SOCIETY:
CONTAINING ITS TRANSACTIONS AND PROCEEDINGS,
AND A SUMMARY OF CURRENT RESEARCHES RELATING TO
ZOOLOGY AND BOTAN DW
(principally Invertebrata and Cryptogamia),
MICROSCOPY, &c.
Edited by
FRANK CRISP, LL.B. B.A,
One of the Secretaries of the Society
and a Vice-President and Treasurer of the Linnean Society of London ;
WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND
A. W. BENNETT, M.A., B.Sc., F. JEFFREY BELL, M.A.,
Lecturer on Botany at St. Thomas's Hospital, Professor of Comparative Anatonuty in King’s College,
8. O. RIDLEY, M.A., of the British Museum, ann JOHN MAYALL, Jon.,
FELLOWS OF THE SOCIETY.
ser. Il V OL. lye PA Rw aA:
PUBLISHED FOR THE SOCIETY BY
WILLIAMS & NORGATE,
LONDON AND EDINBURGH.
ngs) (3) De
he
Vir oe
“unm Toe LY
tne) E ene t) 2h 4-s
=O 1903
JAN
Hopal Plicraseopical Society.
(Founded in 1839. Incorporated by Royal Charter in 1866.)
The Society was established for the communication and discussion
of observations and discoveries (1) tending to improvements in the con-
struction and mode of application of the Microscope, or (2) relating to
Biological or other subjects of Microscopical Research.
It consists of Ordinary, Honorary, and Ex-officio Fellows.
Ordinary Fellows are elected on a Certificate of Recommendation
signed by three Fellows, stating the names, residence, description, &c.,
of the Candidate, of whom one of the proposers must have personal
knowledge. The Certificate is read at a Monthly Meeting, and the
Candidate balloted for at the succeeding Meeting.
The Annual Subscription is £2 2s., payable in advance on election,
and subsequently on 1st January annually, with an Entrance Fee of £2 2s.
Future payments of the former may be compounded for at any time for
£31 10s. Fellows elected at a meeting subsequent to that in February are
only called upon for a proportionate part of the first year’s subscription,
and Fellows absent from the United Kingdom for a year, or perma-
veatly residing abroad, are exempt from one-half the subscription during
absence.
Honorary Fellows (limited to 50), consisting of persons eminent
in Microscopical or Biological Science, are elected on the recommendation
of three Fellows and the approval of the Council. -
Ex-officio Fellows (limited to 100) consist of the Presidents for
the time being of such Societies at home and abroad as the Council may
recommend and a Monthly Meeting approve. They are entitled to receive
the Society’s Publications, and to exercise all other privileges of Fellows,
except voting, but are not required to pay any Entrance Fee or Annual
Subscription.
_ The Council, in whom the management of the affairs of the Society
is vested, is elected annually, and is composed of the President, four Vice-
Presidents, Treasurer, two Secretaries, and twelve other Fellows.
The Meetings are held on the second Wednesday in each month,
from October to June, in the Society’s Library at King’s College, Strand,
we (commencing at 8p.m.). Visitors are admitted by the introduction of
ellows.
In each Session two additional evenings are devoted to the exhibition
of Instruments, Apparatus, and Objects of novelty or interest relating to
the Microscope or the subjects of Microscopical Research.
The Journal, containing the Transactions and Proceedings of the
Society, with a Summary of Current Researches relating to Zoology and
Botany (principally Invertebrata and Cryptogamia), Microscopy, &c., is
published bi-monthly, and is forwarded gratis to all Ordinary and Ex-
officio Fellows residing in countries within the Postal Union.
The Library, with the Instruments, Apparatus, and Cabinet of
Objects, is open for the use of Fellows on Mondays, Tuesdays, Thursdays,
and Fridays, from 11 a.m. to 4 P.m., and on Wednesdays from 7 to 10 p.m.
It is closed during August.
Forms of proposal for Fellowship, and any further information, may be obtained by
application to the Secretaries, or Assistant-Secretary, at the Library of the Society,
King’s College, Strand, W.C. Gon
Patron.
HIS ROYAL HIGHNESS
ALBERT EDWARD, PRINCE OF WALES,
K.G., G.C.B., F.B.8., &e.
Past-Presidents.
Elected.
Ricwarp Owen, C.B., M.D., D.C.L., LL.D., F.R.S....... 1840-1
Dory END EWS. EP), WEES erp sl a Ors fm eevieie le Veh fe els a ot 1842-3
PROMOS PETE, CSTE scons Pele lec eltuiles O¥oOe eee es 1844-5
James Scott Bowrgpank, LL.D., F.R.S.............6. 1846-7
Gmc, pdt eevee die ger crsiee ic ele Outs oeterle cdidel Ss 3 1848-9
PASSE Mn AMER AVE AE) oS Yarn. oie alesse lee se sp bed sacs 1850-1
(MORON ghACKHON, WUT OS. 5 oo isya's nisin, sib )s el w «0, 0 leberd eye 1852-3
Witi1am Bensamin Carpenter, C.B.,M.D.,LL.D.,F.R.S. 1854-5
Figs aN AAT TRERISD a rclie Maia a Sn sles a alin wd '6 2 0 9 67% on tesa 1856-7
Kpwin Lanxester, M.D., LL.D., F.RS.............05 1858-9
JOHN THOMAS Coopmnin NOR S sees cc cc ule obs eles 1860
Roprmrt Jamus Warrants, F.BOS. ........0ccccccoues 1861-2
amis eer, (Wek Ese oa. esl ses elm oo 1863-4
Panes SEAMS MG NEE Bye cist a chia’. fice nia nicstnne + 503 1865-6-7-8
Rey. JosrpoH Banorort Reape, M.A., F.RS........... 1869-70
Wyanrram Kerrpumm Agee. HORS... o cs ecccccccuceawe 1871-2
Cuanuns’ Brookes Mea HUR Bi. ss ctiene. v0 ares 1873-4
Henry Currron Sorsy, LL.D., F.R.S.............0. . 1875-6-7
Henry James Suiacg, F.G.S....... Sides) Baha n.d aud BO lxiabedne 1878
ion 8, bua, M.B., ¥.B.0.P., E.BS...27200. et 1879-80
COUNCIL.
Exzoten 8ta Frsrvary, 1882.
qresioent,
Pror. P. Martin Duncan, M.B., F.R.S.
Vice-Presidents,
Pror. F. M. Batrour, M.A., F.R.S.
*Ropert Brarruwaire, Esq., M.D., M.R.CS., F.L.S.
Rozert Hupson, Esq., F.R.S., F.L.S.
*Joun Ware StEerHenson, Hsq., F.R.A.S.
Creusurer,
Lionet §. Bratz, Esq., M.B., F.R.C.P., F.R.S.
Soeretaries.
*CHARLES Stewart, Hsq., M.R.C.S., F.L.S.
*Frank Crisp, Esq., LL.B., B.A., V.P. & Treas. LS.
Cloelbe other Members of Council.
Lupwie Dreyrvs, Esq.
CuarLes JAmEs Fox, Esq.
James GuaisHer, Hsq., F.R.S., F.R.A.S,
J. Witiiam Grovus, Esq.
A. DE Souza GuimaRAENs, Hsq.
Joun EH. Inepun, Esq.
Joun Mayatt, Esq., Jun.
Apert D. Micnart, Esq., F.L.S.
*Joun Minuar, Esq., L.R.C.P.Edin., F.L.S.
Witu1am Tuomas Surroix, Esq.
Freperiok H. Warp, Hsq., M.R.C.S.
T. Cuarters Waits, Esq., M.R.C.S., F.L.S,
* Members of the Publication Committee,
CONTENTS.
——
TRANSACTIONS OF THE SOCIETY—
I.—Further Notes on British Oribatide. By A. D. Michael,
PAGE
E.LS., F-R.M.S. (Plates T-andII.) .. .... .. Partl 1
II.—A New Growing or Circulation Slide. By T. Charters
Wihite; MER CS: RIMES) s@iiow De a a ees 19
III.—On a Hot or Cold Stage for the ea a By W. H.
Symons, F.R.M.S., F.C.S. (Fig.2)..0 2. .. a 21
IV.—The President’s Address, By Prof. P. Martin Dunean, M.B.
bos Gel ante. RON BN Bot Jeadin: Gomi obKlade: got. Boulleom) ad etwan od oTZus)
V.—On Mounting Objects in Phosphorus, and in a Solution of
Biniodide of Mercury and Iodide of Potassium. By John
Ware Stephenson, Vice-President R.M.S., F.R.AS. .. ,, 163
VI.—On the Threads of Spiders’ Webs. ae John Cain
MD; E.R.M-S.,&e.< ..-: .. 5 G0 is 170
VII.—Note on the Spicules found in the Ambulacral Tubes of
the Regular Echinoidea. By Professor F. Jeffrey Bell,
MEAG HR NES: | (blatenVis) menue: te sect e Partior2 or
VIII.—The Relation of Aperture and Power in the cone ce
By Professor Abbe, Hon. F.R.M.S. if 300
[X.—The Bacteria of Davaine’s Septiceemia, 1 G. F. Dowdes-
well, M.A., F.R.MLS., F.C.8., &c. : 310
X.—On some Micro-Organisms from ents and Hail.
By R. L. Maddox, M.D., Hon. F.R.M.S., &... .. .. Part 4 449
XI.—The Relation of Aperture and Power in the Microscope
(continued). By Professor Abbe, Hon. F.R.M.S. 3 460
XII.—Description of a Simple Plan of Imbedding Tissues, for
Microtome Cutting, in Semi-pulped Unglazed Printing
Paper. By B. Wills Richardson, F.R.C.S.1., Vice-Pres.
University of Dublin Biological Association aly ate 474
XIII—Note on the Rey. G. L. Mills’ Paper on Diatoms in
Peruvian Guano, By F. Kitton, Hon. F.R.M.S i 476
XIV.—Plant-Crystals. By Dr. Aser Poli. (Plate VI.) s. «> Partido 597
XV.—On some Organisms found in the Excrement of the Domestic
Goat and the Gcose. By R. L. cee M.D., Hon.
F.R.M.S. (Plate VII.) Sanalies uae op do oa Jebinn 72)
XVI.—A Further Improvement in the SeagrsosT on: Ether
Freezing Microtome. By J. W. Groves, F.R.M.S. (Fig.
TAG) i vs a secre eee Oo RE a RE ed ee etn
Vili CONTENTS.
SuUMMARY OF CURRENT RESEARCHES RELATING TO ZooLOGY AND BoTany (PRINCI-
PALLY INVERTEBRATA AND CrypToGAmiA), Microscopy, &c., INCLUDING
ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.*
23, 173, 314, 478, 601, 757.
ZOOLOGY.
A.—GENERAL, including Embryology and Histology of the Vertebrata.
PAGE
Photographs of the Developmental Process in Birds .. .. Part1 238
Development of the Paired Fins of Elasmobranchs .. .. 4, 23
Development of the Sturgeon 1. . ws. os oe 0s 24
Development of Petromyzon Planeri .. ee, (eeu 26
White Corpuscles\of the Blood: \*.. s,s 2s eee my 27
Nerve-endings of Tactile Corpuscles .. .. ede ise 28
Distribution and Termination of Nerves in the Ciiea 0 es 29
Influence of Food on Sex. ac ay pate 30
Germinal Layers and Early ieosleprnmn of the Wa. -. Part2 173
Development of Amphioxus.. .. Sues 5 cl mnees 174
Large Nerve-fibres in Spinal Cord of Pike HO WgOOM BOON ty 295
Germinal Layers ofthe Chick :. >. 2. | « +. Pattid alt
Development of Lepidosteus.. ; “ 316
Spermatogenesis in Vertebrates and Aanelida Soamitcde Set Ae 316
Cell-structure oc Fe OM Oc Mee mate cp 317
Theory of Amcboid Maconents oc 319
Distinctions between Organisms and Moras a5 gfe Ok peel 4 areas 320
Division of Embryonic Cells in the Vertebrata .. .. .. Part 4 478
Genesis ofthe Egg in Triton 4. <. 8 «s 26 1 4 479
RORMOAUONIOf RIOTING, “Wee cee lets, eile tem aa fhlssjablel soe Bhs, 479
New Blood-corpuscle .. Bite Ms, Ane re Ars Tees 480
Life and Death in the Aiendh Or ee Dg Boe cn ode ch 481
Pelagic and Deep-Sea Fauna 1s 01 48° bs 0 ae. 483
Symbiosis of Dissimilar Organisms .. .. « «» « Partd 601
PECUIC ONGUNS Of |GAYIMROTUS sol se ss ss ee cae gy 602
Spermatogenesis in Mammalia .. 1. « « « « Part6 757
Early Changes of the Chick 3A oe AO MOY BAC. hob bs 758
Dimensions of Histological Elements .. .. «+ 55 762
Influence of the External Medium on the Saline Gonetitients
of the Blood of Aquatic Animals .. .. ss «oF o 4% 763
B.— INVERTEBRATA.
Fossil Organisms in Meteorites .. .. 20 at. be Path ee
Red Pigment of Invertebrates (T SF, Pn es ne » 178
“ Symbiosis of Animals with Plants Bad, RS ore nor,
and Amyloid Deposits of Spongilla and Hydra .. .. Part 3 322
Paleontological Significance of the Tracks of ae
Lier bebr gen nto Wig Wie ge mn ai a ts pa » 324
Lymph of Invertebrates ©‘. 2 eeeie ce de oe Nas 327
Intracellular Digestion... .. ss «© 06 «8 08 os Part 5 602
* The titles of the papers and notes printed in the ‘ Transactions’ and ‘ Pro-
ceedings’ are also included here to make the classification complete.
CONTENTS.
Development of some Metazoa
Symbiosis of Dissimilar Organisms
Pelagic Fauna of Fresh-water Lakes ..
Mollusca.
Digestion of Ainyloids in Cephalopoda
Proneomenia sluiteri .. 4. we
Maturation, Fecundation and iSegnentniion of ie cam-
pestris dos 0Dt 00. “o™ 0), 100
Kidney of Chiton.. .. +
Morphology of Neomenia c
Development of the Cephalopoda ..
Development of the Oyster
Abortion of Reproductive Organs of Vitri: ma
Morphology of the Amphineura : 50
Anatomy and Classification of the Conialopoda
Ink-Sac of Cephalopoda 00.00, «0d... 60s d=!) Od
Sense of Colour in Cephalopoda .. ;
“ Foot” of certain Terrestrial Gastropoda .
Mucin of Helix pomatia
Rhodope verani
Nervous System of oiascat
North-American Cephalopods 4
Marginella and the (Boia apa)
Vascular System of Naiades and Mi Sea
Sexuality of the Oyster : 6
Curious Secretion in Gesiorasem
Olfactory Organ of Parmacella ..
Innervation of the Mantle of Were linac :
Differentiation of Protoplasm in Nerve-fibres of Toten
Molluscoida.
Deaglynnans Of Sly co 00 90 a6. ca 00 oo
Tunicata of the * Challenger’? :
Organization and Development of the Uscearmen:
‘ Challenger’ Ascidians (Culeolus) bc 60, OO
Embryonic Membranes of the Salpide G5 | pdt bo! -ad
Modifications of the Avicularia in Bryozoa..
New Synascidian .. on
Alternation of Conenttiaiee F im Deana ‘ie on
Tesi-Cells im Ascidian Oud ., 26, 25 oso
Embryology of the Bryozoa..
ING ANG AAO TER OOon Ge
Disdaplia SOT EOEE Ve lCR 1.06
Natural History of Dorotam! 50 0
Development of Ganglion and Ciliated ‘Baer m Ree eset
Development of Genital Products of Cheilostomatous Bryozoa
Arthropoda,
Brain of Crustacea and Insects ..
. Part 6
bed
9
ag Jeeman AL
0
Part 2
7
”?
Part 3
ix
PAGE
763
764
765
30
31
178
179
180
328
330
330
331
485
487
489
489
490
491
603
604
604
605
606
766
767
767
767
32
33
180
182
182
183
331
331
491
492
494
768
768
769
769
770
CONTENTS.
a. Insecta,
Striated Muscle of Coleoptera and its Ner sceaaiee -» Part 1
Terminations of the Motor Nerves in the Striated Muscles
of Insects .. Seer Te sve. Thee
Wings of Insects... . oe
Structure of the Proboscis of pepe =
Post-embryonic Development of Diptera
Development of Adoxus vitis a
Colouring Matter from the Willow-tree eas Be as
Flight of Insects .. Jo | o. Bart
Nucleus of the Salivary Cells “ the ieee of heromamete +
Nervous System of the Larve of Diptera .. ce) es Aare
Occident Ants
Sensations of Sight ee = pemeeae Figs 88 au s) Part 4
Nervous System of the Strepsiptera Eee
Insects which injure Books .
Formation of Galls .. « Seehctess ices Gee a ee
Respiratory Movements of Pasa ee On ume eatin bt SS
Location of Taste in Insects
Parthenogenesis in the Bee ..
Eye of Chloeon diptera., .. «
Marine Caddis-fly :
Want of Cutaneous ees in apes pies
Habits of Ants, Bees, and Wasps ae) oe Mee re
Larve and Pupe of Diptera x
Organs of Flight in Hemiptera .. ..
8. Myriapoda.
Diversity of Type in Ancient Myriapods .. .. .. .. Part6
«e “- on «e ”
”
-- Part 6
y. Arachnida.
Further Notes on British Oribatide. Sage? Land JI.) .. Partl
Liver of Spiders en
Limulus an Arachnid .. .. °
Functions of the Caudal Spine of caomnis “ sl Ae
On the Threads of Spiders’ Webs HPCE. Nobee Gop esis
Structure of the Dermaleichide .. .. .. «2 « «= 9
UCRO ONAN eos uate eco tos “iss cA) testis?) wap) AT hE
Spiders Webs... 25g Wo” ed Scte "Se abe Ss.
Anatomy of Phaienjidar = o> - ce Pare
Scent-glands of the Gicteuconiay toes ( Thelyphonus) ee ee
Respiratory Organs of Arachnids. Oe nae .. Partd
Habits of Scorpions ..
Nest-forms of the Furrow Spider :
Parthenogenesis in the House Spider ..
Segmentation in the Mites
Observations on Scorpions
Insecticolous Acari s
Sense-hairs of the Peau oe
“- “* -* ”
-* o- - oe - - ”
6. Crustacea.
Adaptations of Limbs in Atyoida Potimirim .. .. «. Partl
42
CONTENTS.
Colour-sense in Crustacea
Germs of Artemia salina
New and rare French Crustacea.
(Fig. 28)
New British Cladocera from Grasmere Lake
The Entoniscida .
The Bopyride
Limulus a Crustacean .. ..
Segmental Organs in Isopoda
Bopyride
Classification of the Brain of Grutacan
Unpaired Eye of Crustacea..
Blood of the Crustacea..
Pyloric Ampulle of Potopthaimts C Geusproen On
Heterogeny of Daphnia
Notodelphyide c
Organization of Tr ilobites
Perception of Colour by Crustacea
Mediterranean Crustacea ,
North American Crustacea ..
New Copepoda
Ontogeny of resin Conard:
Aberrant Oniscoids
Blind Subterranean Cr seve in Rep Gennes
Vermes.
Origin of the Central Nervous System of the Annelida
Swim-bladder-like Organs in Annelids
Development of Polygordius and Saccocirrus od
Termination of Nerves in the Voluntary Muscles of the
Leech..
The Echiurida
x1
PAGE
o« Part] 43
Paulin tr as he
. Part 2 186
a a i
i aS
188
sa) S55
ation sou
RESET
338
50 op
.. Part 4 503
Segmental Organs and Genital Gland of some cl Siniediaoe
Anatomy and peat of spores nudus
Sternaspis ... .. .
Hamingia glacialis .. .. «
Echinorhynchus .. .. 2 «.
Proscolex of Bilharzia hematobia
Nervous System of Cestoda .. 2c
Development of the Ovum of Velicerta
Anatomy and Histology of Scoloplos armiger
Parasitic Eunicid.. fe
Development of Anguillula steno ite
Cercaria with Caudal Sete ..
New Type of Turbellaria
Systematic Position of Balanoglossus ..
Nervous System of Platyhelminthes
Structure of Gunda segmentata, and the Ralationshins of
the Platyhelminthes with the Celenterata and Hirudinea
Peculiar Mode of Copulation in Marine Dendrocela ..
Classification of the Nematohelminthes
53 504
3 504
es 505
55 506
55 506
508
Part 5 615
5 615
es 617
617
Part 6 776
9 77
.. 778
. Partl 44
99 44
” 46
“5 46
» 47
3 47
” 48
9 48
> 50
9 ol
”? 51
oh 51
53
Part 2 188
o 190
os 191
Ps 192
> 192
- 194
= 194
a 197
. Part 3 340
ae 240
xll
CONTENTS.
Relations of the Platyhelminthes ..
Entozoa confounded with Trichine
Life- History of the Liver Fluke .. ..
Excrétory Apparatus of Turbellaria ..
New Parasites ..
Tube of Stephanoceros Hichornii..
Chemical Composition of Tubes of Oniiphiss.
Nematoid Hamatozoon from a Camel..
Development of Marine Planaria
Eyes of Planarians
Development of the Orthonaciaa™
Eyes of Rotifers ..
Development of Annelids
Development of the Central Nervous Systm of Arnolds -
Coral-neefivAnnelid) Wc. ae as) ae es os
Muscular Tissue of the Leech .. .. 4.
Observations on the Dicyemide
Orthonectida.. .. ..
New Rotifer (Cupelopagis cine
Synthetic Annelid Te, oe 4
Elytra of Aphroditacean eaends
Phosphorescent Organs of Tomopteris..
Priapulus bicaudatus ae
Anatomy of Ankylostoma punta:
Structure of Trematodes
Adaptation to Environment in the Tr Gian
Vascular Organs of Trematoda ..
Anatomy of Cestodes
Studies on Cestodes a5
Liguia and Schistocephalus ..
New Floscularia .. .. .
Desiccation of Rotifers
Echinodermata.
Development of the Skeleton e the ge ee
Asterias Sc : : 50°" Ta SE Bae ac
Spines of Astorcided a0. ae sere Toscan as
Nervous System of the Oninunotios sae am "OD
American Comatule .. ..
Note on the Spicules found in the Tha peg Tubes oft the
regular Echinoidea, (Plate V.) .. «
Structure of Pedicellarie .. «1 « oF
Circulating Apparatus of Starjishes beh ox Siu) dekere
Genital Passages of Asterias .. 1. se ee
Histology of Temnopleuride Soe ey cou. Moat
Anatomy of Holothurians .. .. ss «6 oe ws
Hybridization of Echinoidea op mock MDD, & Ad | tec
Variation in Asterias glacialis .. 1. ws we
Anatomy of Echinoidss,» sa: usr tyxecy ep apadh wat
Anatomy of Spatangus purpureus cg aoe an, aC
Development of Asterina gibbosa .. 1. 11 ws
oe
PAGE
. Part 3 340
arti:
”
shit» ee
see aT tae,
”
. Part 4
. ”
eeeartio
”
7
peartns
342
342
344
345
345
509
509
509
510
dll
512
618
619
621
621
621
624
625
778
779
780
780
781
782
784
784
785
786
786
787
787
55
56
57
199
199
297
346
347
348
443
512
513
513
626
627
628
CONTENTS.
Brisinga ne
Anatomy of Bonin tise HOLE OOS eee) hp tae
Heteractinism in Echinodermata ,
Circulatory Apparatus of fier Echinoids
Structure and Development of Ophiuroids ..
Formule for Comatulide
Holothuroidea of the Norwegian North ‘Sex cameo
Histology of Digestive Canal of Holothuria Or
Celenterata.
Prodrome of the Anthozoan Fauna of Naples
Metamorphoses of Cassiopeia borbonica ..
Development of Geryonopsida and Eucopida
Fission of Phialidium variabile ..
Crambessa tagi
Seaual Cells of Ey NE KEE
Spermatozoa of Hydrozoa .. oC
Characters of Stinging-Cells of Colennata
Development of the Celenterata ..
Nervous System of Hydroid Polyps
Remarkable Organ in Eudendrium ramosum
Siphonophora of the Bay of Naples :
Ctenophora of the Bay of Naples
Clavularia prolifera .. . 5 ce
Development of Calcareous Skeleton i Astonoiies
Development of Lquorea “ie
Tissues of Siphonophora 1. 1s a
Development of Tubularia cristata
American Acalephe .. 1. as
Sense of Smell in Actinie .. ..
Studies on Celenterates Bo Nite OE
Organization of Hydroid Polyps. Beh nese
JUVE eH oe 5 Rac gee
Vital Phenomena of ice
Ovaries of Actinie dei Geeh Wiese! wise
Skeleton of Madrepores «. se +s ae
Studies on Gorgoniad@.. 2. «s . 26 «=
Development of Aleyonaria .. 1» 11 se
Porifera.
Attempt to Apply Shorthand to Sponges eet
Sponges of the Gulf of Triest 12 «+ «1 «+
Spongiophaga in Fresh-water Sponges Bee Mec
New Eresh-water Sponges 2. «5 «1. o* ae 0»
Hybridization in Fresh-water Sponges sii ao
BOTULG | SP ONGCS: mee ements canes sie a soa sa
Manual of the Sponges Ae ACC ek tence No:
Development of Reniera filigrana es er
New Fresh-water Sponges 1. 1» +» « oF
Protozoa.
Flagellata
pLAaris
~ 39
. Part 6
X1ii
PAGE
631
632
788
789
789
791
791
792
XIV
CONTENTS.
Infusoria Parasitic in Cephalopods
Parasites of the Echiurida .. a
Symbiosis of Lower Animals with Plants e
New Sub-class of Sed rica aaa
Skeleton of the Radiolaria .. « ..
Recent Researches on the Heliozoa
Dimorpha mutans...
Contributions to the Knowiad ie of the Deane:
Protozoa of the White Sea ....
Organization of the Cilio-flagellata
Infusorian with Spicular Skeleton
Contractile Vacuole of Vorticella
Geographical Distribution of Rhizopoda
Classification of the Gregarinida
Psorospermia in Man ..
Myxosporidia
Morphology of Eee
Eozoon Canadense
De Lanessan’s Protozoa as
Kents Manual of the Rees Bc
Flagellata :
Cell-parasite of Prope! Blood ap Spleen (Drepantiom
ranarum) .
Development of Peeper
New Gregarines
Ciliation of the a eraious Tess
Species of Vorticelle she
Acinetide
New Type of Pordattaciis oparnsnefora
Bacterium rubescens Lank. = Monas Ohkenii Ehr.
Biitschli’s Protozoa y 6
New Ciliate Infusorian Bee. “ica 6c
Actinophrys sol :
Nuclei of Pee
Parasitic Protozoa
Intestinal Parasites of Oy tig
BOTANY.
laieTii) 5
) Partie
A.—GENERAL, including Embryology and Histology of the Phanerogamia.
Origin of the Embryo-sac and Functions of the Antipodal
CHI ca loch 0b Si ice
Palveniamas in Ramee
Resistance of Seeds to extreme Cold
Mechanical Contrivances for the Dispersion of Seeds te
Fruits
Chemical Difference feneen Bead. ih ieee. Prien a8 =p
Energy of Growth of the Apical Cell and ae the ae
Segments ....
Action of Nitrous Onide on Vegetable Cie
Chlorophyll and the Cell-Nucleus .. ae
CONTENTS. XV
PAGE
Influence of Warmth of the Soil on the Cell- HON Ce of
Plants : : liter . Part1l 70
Growth of Staacrgrains by Tiivccoceatap, £ 70
Collenchyma be ” 71
Epidermis of the icin of Serspecent: ane) Darling Gena 9% 72
Laticiferous Vessels BRN AA ONG are sia ree eh ty Ibis + 73
Epidermal System of Roots .. 73
Passage from the Root to the Stem Ms 74
Causes of Eccentric Growth Pr 74
Hydrotropism of Roots., .. Fe 74
Cause of the Swelling of Root _fibres 3 75
Frank’s Diseases of Plants .. .. . o o0 oc 75
Free Cell-formation in the Embryo-sac of Wnoscornns 5 Part 2 214
Fertilization of Apocynacee 5 215
Cross-fertilization and Distribution of ‘Seeds 368
Fibrovascular Bundles of Monocor aeons a * 370
XVl CONTENTS.
PAGE
Sieve-Tubes .. .. 50 co co coe pomeciind). Sg
Structure and Danan of Stomata opt no cok oon oo |) cp 372
Stomata of Stapelia .. .. $4 372
Influences of External Forces on aie Direotion a Gr ue % 372
Water Distribution in Plants -.. . PoC nee. 373
Causes of the Movement of Water in Pits 5qy Gob gcd. 6D 373
“ Compass-flowers” .. a 373
Chemical Difference ieee Dead on Living Pr saps.
(ERG MOO) Weens en ws ie he! Gey oe (Rartitone
Killing of Prien by Yy Va arious Saegeats Aiea oo SEO cp 522
Apical Cell-growth in Phanerogams .. «1 «+8 08 459 523
Development of Bordered Pits .. » 923
Development of Tissue as a Characteristic of Grows of Plants =) 524
Stomata of Polycolymna Stuarti are Sos 0b 524
Properties and Mode of Formation of Dunas 6B. BE 3 525
History of Assimilation and of the Functions of Cnorophyl + 525
Theoretical View of the Process of Assimilation x TREY Ss 525
First Products of Assimilation .. .. 6 of «6 « 4 526
Absorption of Metallic Oxides by Plants .. .. 5 526
Decomposition of Calcium carbonate in the Stem of Theat:
VEGOnOUSSVVOOUS/t.4 tose ‘ecm ces Wrest Dich Meee eee tae | as 527
Hypochlorin .. .. Shi) ont Ot MOG! Orn Ok oy 528
Latex of Euphorbia athe ttc 5 529
Darwin's so-called “* Brain function” of the Tips of Pe a Entry of eee
IACUSTMIS§ Hse, Aas he oe Brae? ude (ach ate 373
Schizewace@ .. .. co Noe ee od) on, Uiahd: GBS
Wale Fructification of Politrichien Souipoce fod, ne ec ol GE OEE
Muscinee.
New Genera’ op Mosses. a 210) ma et ee oe Parak 79
Classification of Sphagnacee sail Teja, jaa ea eM sa), . las 79
Female Receptacle of the Jungermanniee Geocalycee -. Part 2 227
Vegetative Reproduction of Sphagnum Sahy ewibetesr | se) - Shee 228
Ser. 2.—Vox. IT.
b
XVili
CONTENTS.
Chemical Composition of Mosses.. 11 ss as
Branched Sporogonium ofa Moss .. .
Influence of Light on the Thallus a Bonckantia
Goebel’s Muscinee oe Some alunes
Classification of Seiad bo von icon ce
Wale Fructification of Polytrichum
Characee.
Cell-nucleus in Chara fetida are
Development of the Cortex in Chara ..
Fungi.
Conidial Apparatus in Hydnum .. 11
Alternation of Generations in Uredinee
Mode of Parasitism of Puccinia Malvacearum ..
Sterigmatocystis do. dé) ne
Oospores of Phytophthora ceria dite: Ghee o6
PELONOSPONAOVLICOLG aon Neel toe eel ee) inte
Vegetation of Fungi in Oil .. 6. 20 ewe
JENS VEOIIYRYS ou 20 6a 80 ot toe
Ear-Fungi .. . . 50 Col yan ty os
Insect-destroying Craptagan AON sche Lor
Brefeld’s Schimmelpilze .. . “e
Influence of Light on the Growth of Penicillium
Production of Microphytes within the Egg ..
Aitiology of Diphtheria ae oe ope
Properties and Functions of Boaters
Atmospheric Bacteria ..
Pathogenous Bacillus in Drinking Water
Connection of Diseases with Specific Bacilli
Origin of the lowest Organisms
Prolongation of Vegetative Activity of Choropylin Cells
under the influence of a Boa AG moo ne
Action of Light on Fungi... oy Wes
Chemical Nature of the Cell-wall in Pere
“ Mal nero” of the Vine .. «.. 2
Roesleria hypogea parasitic on the Vine
Didymospheria and Microthelia.. .. ..
Peronosporee and Saprolegnice .. .. «+ as
Fungi in Pharmaceutical Solutions .. .. «
Vegetable Organisms in Human Uameienta a
Saccharomyces apiculatus .. ss 46 we we
Etiology of Malarial Fevers Sy CMC ex
Aktinomykosis, a new Fungoid Cuttle-Disease 3
Infection by Symptomatic Anthrax ..
Experiments on Pasteur’s Method of Anthrax- Vaca
Duration of Immunity from Anthrax gh sion
New Method of Vaccination for Fowl-cholera ..
TRADES! we (ise oes: RUT Eo eISSN Veo Mors
Bacteria of Disodine’ s Benton
Influence of Oxygen on the Development of ‘the eee Fungi
PAGE
7 wattio ust
. Part 4 534
a 534
seas 535
»» Part a'Ga5
. Part 6 823
Parthia
. Part 4 535
. Partl 80
» 80
” 80
” 80
” 81
” 81
- 81
op 83
35 83
=n 83
s 83
45 87
” 87
9 87
” 88
o. :
” 89
= 89
45 90
i 93
- Part 2 298
» 228
» 229
» 229
288
» ) ee
> ee
» 284
» 284
ues
» 236
>. age
» 288
» 239
» 289
239
. - Part 3 310
>» Joie
CONTENTS. x1x
PAGE
Chatomium .. «. 50 ido derbanas Bis
Completoria Shines s a Barasie on ys lesoanin of
Ferns ie AG aon NOGTEM Or Ne ae Becca nos Conn eer 377
Rehnvs Uscbnncates 00, 10 so nici ED Asie deleicielee | 5 378
Destruction of Insects by Ye oiseh te ns 378
Development of Fungi on the Outside ag Tasvie of “Hen’s
Eggs .. +» Boy Oe Soe took Lod | van rots doe mer 378
Biology of Bacteria a0 | A bi eitoe + 380
Influence of Concussion on the Deneimnent of ‘the Schizo- + 382
mycetes .. 3 382
Experimental Pr ecction of we Bacteria of the ‘Cattle-
distemper .. .. Siebrsleis Picea Me ciavecn “iss 382
Bacteria of Caucasian Milk jin So Gn a6 1.00) | ode es 383
Parasitic Organisms of Dressings .. os © « « 4 384
Parasitic Nature of Cholera BOs Noo) Heol BO) Od. Sonn arp 384
EOrasitismy Of, Luberculosisis.m sajei set aah lepencani se) 55 384
Haperimental Tuberculosis oo) os 21 se ewe se gg 385
Etiology of Tubercular Disease .. .. 00°. gp 385
On some Micro-organisms from iguionenor lies ‘spe Hait . Part 4 449
Ustilaginee .. .. AEIBE OM Nor EaO0 cakes 536
Unobserved Soieitineness in Paycomijees bo 00-00. 06 538
Beltrania, a New Genus of Hyphomycetes.. .. .. «. 45 538
Chemical Composition of Moulds... .. 1. 1. os ae 49 538
Salmon Disease .. Bon ere cae ere 538
Formation of Gonchrenisreen ¢ in Nutrient Fluids Cua ea ;
various Proportions of Nitrogen .. a 540
Morphology and Genetic Relationship g Pathogen
BOCLORUD wot ayes te oeneleee cise Gels ay NGO GO) FH 541
EGLhOG CNOUS NESS
ess
» 689
» 658
» 692
» 692
» 692
» 693
» 696
> eS
» 699
» 00
nes
> a0
Part 6 842
5 aaa
» 852
eae
ee
»- sae
ages
» 854
> es
es
» 859
CONTENTS. XXV
PAGE
Gundlach’s Substage Refractor .. .. «.. « « «» Part6 860
Apparent Size of Magnified Objects .. .. «+ «+ « 4 861
Committee on Ruled Plates .. bra COwavoha tach. doc 5 861
Quekett Microscopical’ Club... 35 ts we owes Be 861
Hogg on the Microscope po oO einai ad Hi soo abot ek Cach mime 862
Wright's ‘ Experimental Optics’ Gab de Loo. (ANON eet ney; 862
Moore’s Camera Lucida etna Gas RAMAN chek Cn erat) Be 95 865
New Mechanical Lamp ae Aes Bp a ino wk itary 866
Tolles’ Objective with Tapering Fr oo oo) yoo! tone dde =a 904
B. Collecting, Mounting and Examining Objects, &c.
Durable Preparations of me gee Organisms ., .. Part1 120
Preparing Anthers .. a0.) gp 122
Herpel’s Method of Pr ae Fungi for the eanan bo gf 122
Dissociation of Gland-Elements .. . Ob) G0. ep 123
Method of Preparing and Mounting Soft Tissues Sutras 123
Preservation of Anatomical Specimens 50) do boo gp A
Barff’s Preservative for Organic Substances Srsdiea cine Rapa uh ber 124
Injection-mass.. 860 OO SOB) a tae edo ©8400. Go Gs 125
Imbedding Delicate Oasis 90 00.) 002 a0. 00 400.00 Fp 125
Katsch’s Large Microtome. (Fig.25) .. «1 se veg 126
Cox’s “ Simple Section-cutter for Beginners” .. .. .. 5 126
Cutting Sections of very Small ede FAV ootgeaobies Sabet aes 126
Mounting in Balsam... .. Bic Nacesnerioam ahopal Ske An 126
Mounting in Glycerine.. 12 «+ +6 66 es wwe 127
Smith's Slides ati ABs Sob HOO ROE whoo becom rp 127
Spring Clip Board. (Fig. 26) D0: 6D. Ob, $86»? 00.668 gp 128
Examination of Living Cartilage +s 0 128
Statoblasts of Lophopus crystallinus as a test hep High-power
Objectives.—Areolations of Isthmia nervosa .. .. 5 129
Microscopical Structure of Malleable Metals .. »» »» 4 130
Sections of Fossil Coniferous Woods .. .. oO 131
Aeration of Laboratory Marine Aquaria. (Fig. 2)... cs, 131
On Mounting Objects in Phosphorus and in a Solution of
Biniodide of Mercury and Iodide of Potassium .. .. Part 2 163
Injection of Invertebrate Animals Ag secant Coles Mllpeth “vole 5 274
Goths IGYARHOG PUCES oo 00 00 00 50) 000 oF 275
Staining with Saffranin AO. LE SOO ata ciOnyeO tna 0ati. Rede eeco 33 275
Staming with Silver: Nitrate... 2. «6 « © «=» »% 99 275
Staining Tissues treated with Osmic Acid .. .. +» «5 4 276
Mounting the ‘‘ Saw” of the Tenthredinide .. .. «. 276
Mounting Butterfly-scales .. .. «ss oF «5 «2 oF 499 277
Imbedding Ctenophora.. .. so O dal iinadh Vee 278
Staining Living Protoplasm with Benearal: Ean a0. Dp 278
Preservation of Infusoria and other Microscopical Organisms ,, 279
Staining the Nucleus of Infusoria Moc) areal San Seed creamer lt rey 280
Aniline Dyes and Vegetable Tissues .. 11 «2 «+» « 145 281
Indol as a reagent for Lignified WETS » Ane ete x 282
English’s Method of ee ie and Wild
LRMIGS. 5 odo i Hate Sy Boo
XXVi CONTENTS.
PAGE
Mounting Salicine Crystals... «6 +e we we Swe «Part 2 283
Bausch and Lomb Turntable. (Fig. 59) Foa ace 284
GrapithiGell Vasu nie vost ood Mtawm Wee | (set Wee)! )) el Bee teas 284
.
.
J
.
Bausch and Lomb Circle-cutter. (Fig. 60) ae) sie Lae MS 285
Was and Guttapercha in we ae Ze eS Reet See ee 285
PA Craton Uj PAGILATAG ecue Msctmees can esi etal ela) tote Ann tay 286
TERRE CURES LEE “ag G0” So a0 “dow BOM LOB Bad ok oo 287
Microscopic Curiosity .. sq cd) oe 288
Colouring Living cnaae tend Depa: noe ot _ Pat 3 425
Mounting Histological Preparations with Carbolic Acid ae ;
Balsam... Stee ak Ode moc 35 425
Differentiating Motor ae PET Ner DAT Oa ROW MIA co | of 425
Preparing Nerve-fibrils of the Brain .. «2 01 ee ww 426
Cochineal Carmine-solution .. .. he ome ap 426
Polarized Light as an Addition to Sta aining 5b. oda oy 426
Wickersheimer’s Preservative Liquid . se aes, See ass 427
Preparing Hemoglobin Crystals bite om Wccvnestcle Wier anelies 427
IPrrescroung eH VOWELS a itioh whe tse aisle iste OL tns ass 428
Cleaning Diatoms.. .. eG ed od co 8 428
Gaule’s Method of Tmbédding oe a 428
Williams’ sage Micr otome adapted ae Use anitl ‘Ether,
(G&G SED) on bo Sa 430
Swift and Son’ s Fayraged Masaons: “Fe ie 84-87) od oF 432
Bausch and Lomb’s Standard Self-Centering Turntable .. 434
Crystallized Fruit Salt.. .. se we 5 ave keviegthee ol aiess 435
Cleaning Gizzards ae Meas) cate Nasa kee Meck ato ane ete 435
Mounting Starches si FO. rcp Oe rode 435
Home-made Apparatus for Coliactond. dee fos pti aoe yoo ee cp 436
Preparing Foraminifera... sot 436
Mounting Volvox (Cf. also pp. 585, 586, aad 746) .. + eos
Cleaning and Mounting Gizzards Seba Peels oles geen se “ako Osane
Glycerine Jelly Mounts EE clon tgad) WsealMete agotheghars Ges Meecoienes
Examining Rough Minerals... .. Ah og | ob. Oo as 437
Keeping Objects Alive for many Months es 5 438
Examining Circulation of Blood in a Tudo’ Tail (Ch
AIO MD OOG) aa. ees 5 as | ES 438
Transparent Injections of a veal Manna | WS Ae oD 438
Preparing Entomostraca .. ‘ as 439
Simple Plan of Imbedding Tissues oe one Cutting in
Semi-pulped Unglazed Printing Paper .. .. «. « Part 4 474
Cutting and Mounting Microscopical Sections .. « « 4 567
Preparing Blastoderm of the Chick .. ss «+ «+ «+ 5 570
Preparing Embryos of Insects .. «. Seyi bel calin bec aes 570
Collecting, Staining, and Photographing Rude apes | as 571
Ehrlich’s Method of Exhibiting the Bacteria of Tuberculosis 572
Preserving Infusoria and Amebe cial yA. ates Haas omaeee Ce Tas 574
Preserving Protozoa .. .. oe; ase PG MSCS. “cs 575
Staining the Nucleus of Living Tabane se hie Oy cae as 576
Double Staining with Carmine and Anilin Green nay some Sey 576
Outing Sections of "Coal, in y.0 see fess) eel igs 577
CONTENTS.
Sections of Mica-schist ..
Paper Cells .. 6 00. 66-1 90") 60 han
Was, Cells... as bude of We cince used Wiicls
Miller’s Caoutchouc Canes 90 00. 00.60
Mounting in Phosphorus 90 6
Vacuum-bubbles in Canada oan 00 ad
Mounting Moist Objects in Balsam
Moisture in Dry Mounts
Dammar Varnish . bb Bacio HG
Cleaning Used Slides and Case
Resolution of Amphipleura ipalncida ae
Microscopic Examination of Wheat-flour
Destruction of Microscopical Organisms in Potable Water
Public Lectures in Microscopy 50
Preparing Stellate Hairs of Deutzia ..
Examination of Leaves
XXVll
Preservative Fluids for Animal ae Weqenile iiss, and
Methods of Preservation ..
Preparing Sections of Aais-cylinder
Mounting Gizzards of Insects
Preparing Tape-worms
Staining and Preserving Tube- ante
Method for Dry Preparations
Preserving Infusoria 60; / 00
Mounting Mosses and Hepatice ..
Preparing Bacteria of Tuberculosis
Preparing Diatoms a0
Modification of Paraffin- Anteniog 50
Perenyi’s Hardening Fluid .
oP)
Satterthwaite and Hunt's Freezing Sechioncutien| (Fig. 138 5 710
Windler’s Microtome. (Figs. 135 and 186)...
Marsh's Section Knife. (Figs. 137 and 138)
Thanhoffer’s Irrigation Knife. (Hig. 139)
Differential Staining of Nucleated Blood-corpuscles ..
Flemming’s Modified Method for Staining Nuclei
Lodine-green for Human and Animal Tissues
Teichmann’s Injection-mass ..
Wywodzen’s Injecting Material ..
Mounting in Pure Balsam ..
Centering Objects on the Slide ..
Chalk Cells
Line and Pattern oun .
Kain’s and Sidle’s Mechanical Bangers’ a 140) .
Venice Turpentine as a Cement .. 20. 06
Metal Caps for Glycerine Mounts
Nassau Adjustable Spiral Spring Clip. (Fig. Taye
Green Light for Microscopical Observations
Photo-Micrography
PAGE
ee athaeonc
5 578
35 578
9 579
i 579
ee ess 581
ae 582
os 583
Sal os 583
ee aes 583
saenigs 584
. 584
3 585
. 585
BAe de 587
fences 590
Part 5 701
a 703
as 704
5 704
5 705
5 705
ny 706
a 706
on 706
op 707
» 708
709
5 711
a5 712
35 713
55 714
5 715
on 716
3 716
po wiley
se ee
LT
o 718
S 718
os 721
= 724
[ 725
oS 725
po 12D
A 726
Woodward’s Photographs of Aniplipteara aa Dieu: junnna 5 727
Microscopical Examination of Handwriting
a, te
XXVill CONTENTS.
PAGE
Haamination Of-Sputa se 2, 25 cs we ws so, ATO
Trichina-Examinations Ac uber Sock. oh 728
Continuous Observations of Minute anienacil Fee acl teensy 731
Microscopical Examination of Textile Fabrics .. .. «+ 5 732
The Microscope in Engineering Work... .. «2 «ss «oF 733
The Microscope in Metallurgy .. ee toe, 889
Gum and Glycerine for Imbedding .. .. = 890
Roy’s Microtome. (Figs. 163 and 164) .. «1 «2 +» 1459 892
Boecker’s Microtome with Automatic Knife-Carrier. (Figs.
165-167) .. .. Pape eee! Mie ne eres Bes Se 893
Staining Bacillus Fascias emits Were, (eke enna Wl Mas Ald 895
Substitute for Canada Balsam .. 15 20 6 oF «2 9 898
Cnn GISeCONe MGIPES, “"L.0y st) ss ues) ee) | Wer) eens 899
Staining Fat-cells ee ae toe ie ees 899
Taking up Small Objects by Suction Tubes SAD Lob. 2p 900
BIBLIOGRAPHY—MIcROSCOPY a Be ietsh ise ecole 4 io yqtaee inate’ Sia eae ne
” - - on oe oe “- oe oa ”
;
°
mR
Q
‘S)
Lae]
Ls}
D
Qn WH Raho
bo
[o'e)
Sap nice Nag lsen Tete aa a en Co sea ea eh ee ADE
Proscolex of Bilharzia b= BUDE gia use ap etna IF bel ok ne Gait Seo SE
Nervous System of Ces# y eit SIE DE eae are Rats a tie eR eC |
Development of the Ovu* of Melicerta aie eh ate Tk a pier plat cower an i eae eee DO
Development of the Skeleton ul the Eee Be re pak salt notte oalhes sea wa Poe
Asterias < er BB wise O's hth HESS Sosa ae OO
Spines of Asteroidea .. Wee Peerage tear een Sette ak TOT
Prodrome of the Anthozoan Fauna of Naples Sea) any Ban gee ty ROW ese ay /
Metamorphoses of Cassiopeia borbonica .. > 1 ss news ta eS
Development of Geryonopsida and rane Rega igi ea, ate aise og Cea eS
Se 3 Fission of Phialidium variabile See rate RED he oe Res ede tage
eee ~ Crambessa tagi .. halt hep CpeR I eee Coats be eet Pee th cays net DO
Sexual Cells of Hydroida UP Ne fet S RY aS ti Sea on Re YE Cia ogee |
Spermatozoa of Hydrozoa :. —. Sep REL Ava oie ate ee ps Geet ee OO
Attempt to Apply Shorthand to Begnaes BaD eee Be SU ae es eee OL
Flagellata.. Leelee tes cng eee : 62
_ Infusoria Parasitic in Cephalopods RES ha es Bey = 63
Parastes:0f the chide <6 casos.) fae 8 he ees aka RE eas = ve Fe OB
Botany.
=Drigin of the Embryo- sac and Functions of the Aupelal pel ve . 64
Polyembryony in Mimosez . = ob | hen BS or OD
- Resistance of Seeds to extreme Cold .. sro ae VO0
Mechanical Contrivances for the Dispersion of Seeds and “Pritts partes te OG
Chemical Difference between dead and living Protoplasm hee
Energy of Growth of the Apical Cell and-of the youngest Seginents detiiee OU
Action of Nitrous Oxide on Vegetable Cells a ee
Chlorophyll and the Cell-Nucleus Sige eer earns Oe
Influence of Warmth of the Soil on the Cell. formation g. Plants
- Growth of Starch-graimns by Intussusception esse
Collenchyma _ nc Sa serrierteo reed | t
_. Epidermis of the Pitchers of Sarracenia and Darlingtonia eigen Vole enue ke
acres perous Vessels” ee Oxs eae G2 oe he SF ins ain) Cag eB a ee TD
Epidermal System of Roots Slee Glad boa May oGeadal Sues, oa its ak UO
f Passage from-the Root tathe Stem 3.0 ve ee ce ne ee ae oe A
Causes of Eccentric Growth eR an wees Sead ge TE lod OR SGU FL
Hydrotropism of Roots : SC emICN See Oe GR RG Fone es ee
- Cause of the Swelling of Root-fibres STO i eer Nee VERE T Sgn Ge pa omer {5%
Frank’s Diseases of Plants... .. 1, ss Bolg ar dames See ag ee a
Prothalliwm and Embryo of Azolla ..... APPR GONE SES EY [1
Development of the Sporangia a at Spares o Tsoctes: tn vee cae EB
- New Genera of Mosses .. .. x obras ges tan yaa ge
Classification of Sphagnacez Sera Penne Pe ae ETE PR EE a AS
Cell-nucleus in Chara fectida — 26-00 0e ce se a ee ee ee 9
__ Conidial Apparatus in Hydnum 1. eee ae ne ce eee 80
- Alternation of Generations in Uredinee .. 1. +s ae as ws aw ee 80
Mode of Parasitism of Puceinia Malwacearim fa Bh Goad AiG) hs Meera sae SOO
- Sterigmatocystis ... Seas 2 ‘ os ae pa SO
Oospores of Phytophthora infestans Pe ao : F . i ee Ok
pane ~ Peronospora viticola GaAs Hp ees Paka OR 4 - - Sl
- .. Vegetation of Fungi in Oil . " eee, 3. §
ores PAT OSTA PRUIGE 6.2 0 We Seal Sih By iad idem. Gist bey hae ea Se eee ee
_ Ear-Fungi... wad Heiss pains Rios LI ew oh Ue OR EL. aie ee ES
~ —Insect-destroying Chieienate Sere a iret Seer rer eee By SR REE OES ae 30.
Brefeld’s Schimmelpilze — .. Spee ee Peete ie Se pene ep ISD
~ Influence of Light on the Growth of Penicillium pape nee eS : 87
Production of Microphytes within the Figg eee NE Ee > 87
: Atiology of Diphtheria —.. WEES Ear : x SBF
Properties and Functions of Bacteria. Se eng hong eerie S92 ve 2h ga ae oe 8g oe aw? ees oa EO
Diatoms Of -Thannee: Mak i635 5 OS ge ae. ae te eee
Microscopy.
Goltzsch’s Binocular Microscope (Figs. 3 and 4) 4. © we we es
Hartnack’s Demonstration Microscope (Fig. 5) .. 85 Foe
Lacaze-Duthiers’ Microscope with Rotating Foot (Big. | 6)
Nachet’s Portable Microscope (Figs..7-11) — ..
Parkes’s ‘‘ Drawing Room” Microscope ..
Piffurd’s Skin Microscope (Fig. 12) Ree Sime aco tit 7
Robin’s Dissecting Microscope (Fig. 1) ss Bae Abts si Semple
Briicke Lens (Figs. 14 and 15) Bes aA Ga Ope an eek
The Model Stand -
. Denomination of Ey ye-pieces ‘and Standard Gauges Jor same
Braham’'s Microgoniometer : Bese oe
Watson’s Sliding-box Nose-piece ( Figs, 16 and 17)
Deby's Serew-Collar Adjustment (Fig. UT) Se apes
Number of Lenses required in Achromatic Objectives
Colour Corrections of Achromatic Objectives ..
Verification of Objectives .. Orang ea
Schultze’s Tadpole-Slide (Fig. 19)
Stokes’s Tadpole-Slide (Fig. 20) ..
* Swinging Substage’ » or & Swinging uil-pizee”
Value of Swinging Tail-pieces*... ..- .
Ranvier’s Microscope-Lamp (Fig. 21) Br rey pea oo
Hollow Glass Sphere as a Condenser... o voee tae aaies
Stein’s small Microphotographic ee Cig 22) Fe tae
Ranvier's Myo-Spectroscope (Fig. 23)... PEERS
Standard for Micrometry .: -+ ee ae te te ene we
Rogers’ Micrometers (Fig. 24) . ‘ fs
Section of “ Histology and Microscopy ” at the ‘American Association :
Structure of Cotton Fibre .. - . 5 ea oo eee
Durable Preparations of Microscopical Organisms Aen eter oD
Preparing Anthers _.. ns eet eee
Herpel’s Method of Preparing Fungi for the Herbarium deat ge Re
Dissociation of Gland-Blements if . = be SSP ee wine
Method of Preparing and Mounting Soft “Tissues.
Preservation of Anatomical Specimens .. 6s tenet nee
Barf’s Preservative for Omani Substaysces <5 eat so sass > Gs eae
Injection-mass.. SFE IRL OR MS ek FE Part SY Coe
Imbedding Delicate Organs Bo Stree: crap ee earl nee More ie
Katsch’s Large Microtome (Fig. 95) Reema. SAE a cup tt pa ap ten
Cox's “* Simple Section-cutter for Beginners” Biscay: Ses Pay ae
Cutting Sections of very Small PG suri oe Se rf
Mounting in Balsam... ED eRe te ee, si
Mounting in Glycerine sre See keari vies: suerte eee =
Smith’s Slides — -«. Twat de ee” Me ans taal ene eign
. Spring Clip Board (Fig. 26) - pele Wis hater Ppllgics < Seu Are GF:
Examination of Living Cartilage ia
Statoblasts of Lophopus erystallinus.as a Test for High-power Objection 5 aS
Areolations of Isthmia nervosa... +... ys
Microscopical Structure of Malleable Metals bien) SI aee es
Sections of Fossil Coniferous Woods aa Pet ae et
Aeration of Laboratory Maring Aquaria (Fig. 2 spauh asi enant
PROCEEDINGS OF THE Soorrry ae wa age c ade Sage Pot i
— Bopal Microscopical Society.
MEBTINGS FOR 1882,
At 8 PM,
1882. Wednesday, JANDARY ee’ Ore Ot ee AT
Be FEBRUARY... p23
(Annual Meeting for Election of 0. ficers
and Council.)
Wane: BL gf ois te AES ae eee 8
S PEP RIT eos ae ae ee BAND
ME Anh Se EE ey eas ea tey eee RO
e SPUN sce a ae oe re ee
Se OcTOBER Eee Sie oy ake te ey eek
5 - Novemser ais ee se aia ae a 8
is DECEMBER ey es eee) TS
THE “ SOCIETY? STANDARD SCREW.
The Council have made arrangements for a further oe of Gauges
. and Screw-tools for the “Socrery” SranDaRD Screw for OBJECTIVES.
‘The price of the set (consisting of Gauge and pair of Screw-tools) is
: ‘12s. 6d. (post free 12s. 10d.). ee for sets should be made to the —
_ Assistant-Secretary. ©
For an explanation of the intended use of the gauge, see Journal of the
SS Batty, L. ae pp. 548-9.
_ ADVERTISEMENTS FOR THE JOURNAL.
a “Mr. Cuartes Buencows, of 75; Chancery Lane, W.C., is the authorized
Agent and Collector for Advertising Accounts on behalf of the Society.
(oS)
NOMINATIONS FOR THE COUNCIL.
8th FEBRUARY, 1882.
Proposed as PRESIDENT.
Pror. P. Martin Duncan, M.B., F-.B.S.
As VICE-PRESIDENTS.
_ Pror. F. M. Batrovr, M.A., F.RS.
*Ropert Brarrawaire, Esq., M.D., M.R.CS., F.LS.
*Ropert Hupson, Esq., F.RS., F.LS.
JoHN Ware SrepHenson, Hsq., F'.R.A.S.
As TREASURER.
Lionet §, Bears, Esq., M.B., F.R.CP., FBS.
As SECRETARIES.
CHarues Stewart, Esq., M.B.CS., F.LS.
Frank Crisp, Esq., LLB. B.A., V.P.LS.
As Twelve other MEMBERS of COUNCIL.
*Lupwie Dreryrus, Esq.
Cuartes James Fox, Esq.
James GuaisHer, Esq., F.RS., F.RAS.
*J. Witu1am Groves, Esq.
"A. pe Souza GuimaraEns, Esq.
Joun KE, Inepen, Esq.
Jonn Mayatn, Esq., Jun. se ees
Arsert D, Micuarn, Esq., F.LS. » a on Ce hee os
*Joun Mizar, Esq., LRCP.Edn, FLS. =
@Wrwam Tuomas Surrors, Esq. Se ag
“Freverick H. Warp, Esq., M.R.C.S, .
T. Cuarrers Wurrs, Esq., MRCS, F-LS.
* Have not held during the preceding year the oflice for which they are nominated. e
(7:2)
I. Numerical Aperture Table.
The “ AprrtuRE” of an optical instrument indicates its greater or less capacity for receiving rays from the object and
transmitting them: to the image, and the aperture of a Microscope objective is therefore determined by the ratio
- etween its focal length and the diameter of the emergent pencil at the plane of its emergence—that is, the utilized
diameter of a single-lens objective or.of the back lens of acompound objective.
This ratio is expressed for all media and in/all cases by n sin uw, nm being the refractive index of the medium and wu the
-semi-angle of aperture, ‘The value of 7 sin w for any particular case is the “‘numerical aperture ” of the objective,
Diameters of the ~ Angle of Aperture (= 2 w). Theoretical
3 * 2 : Pene-
Back Lenses of various * | INumi- Resolving a
____ Dry and Immersion Wamorseat D Water- | Homogeneous-| nating Power, in paLe
~~ Objectives of the same Py Da pees OD} ee Immersion\. Immersion | Power. | Lines to an Inch.| ~?Y*"-
- Power (4 in.) ¢ = yechiveS: | Objectives,| Objectives. | (a2) | (A=0°5269 1 e )
from 0°50 to 1°52 N. A. @=1) | =1:33.)) (m = 1°52.) =line 2.) a
180° 0! |2°310| 146,528 “658
161° 23’ | 2°250 144,600 *667
153° 39’ | 2-190 142,672 *676
147° 42’ | 2-182 140,744 "685
142° 40/
Fo Aa ee ie
wa), 1842 10!
fo ee 13002 2!
126° 57’
is 123° 40
180° -0'|. 122° 6!
165° 56’| 120° 33
155° 38"| 117° 34’
148° 28’| 114° 44
142° 39’| 111° 59’
137° 36"| 109° 20° |
133° 4"| 106° 45!
128° 55} 104° 15!
125° 3"| 101° 50!
121° 26"| 99° 29’
|118° 00'| -97° 11’
114° 44"| 94° 56’
111° 36"| 92° 43’
108° 36’} 90° 33’
105° 42"| 8° 26’
102° 53’| 86° 21’
-074| 138,816 | +694
‘016. 136,888 | -704
-960| 134,960 | -714
“904| 133,032 | °725
-850| 181,104 | +735
-796| 129,176 | *746
Hq. 128,212 >|. 752
-742| 127,248 | +758
-690| 125,320 | -769
-6388| 123,392. | -781
121,464 | +794
“588| 119,536 | -806
‘488| 117,608 | °820
-440| 115,680 | +833
-392| 118,752 | +847
-346| 111,824 | -862
-300| 109,896 | +877
-254| 107,968 | -893
210} 106,040 | +909
-166| 104,112 | -926
-124| 102,184 | +943
082} 100,256 | -962
100° 10’| 84° 18’ |1-040| 98,328 | -980
0’ | 97° 81"| 82°17" | 1-000} 96,400
9/1 94°. 56"). 80° 17’ | 960) 94,472
99 | 99° 94’| 78° 20"| +922) 92,544
6’ | 89° 56’| 76° 24’) -884| 90,616
51! | 87° 32'| 74° 30’| °846| 88,688
19’ | 85° 10’| 72° 36"| -810| 86,760
17’ | 82°.51'| 70° 44 | -774| 84,832
38’ | 80° 84'| 8° 54’ | -740| . 82,904
17’ | 78° 20'| 67°°.6' | -706} 80,976
10’ | 76°. 8’| : 65° 18' | -672| » 79,048
16’ | 73° 58’) 63° 31’ | -640| 77,120
81! | -719.49'| 61°. 45' | -608} 75,192
56’ | 69° 42"|. 60° 0’ | -578| 73,264
28' | 67° 36'| 58° 16' | +548; 71,336
6". | 65° 32/| 56°32’ | +518) 69,408
Bl’ | 68° 31’| 54° 50’ | +490} 67,480
41’ | 61°-30'| 53° 9' | +462| 65,552
36' | 59° 30°}. 51° 28’ | +436 63,624
35 | 57° B1’|° 49° 48’ | -410| 61,696
38’ | 55° 34’| 48° 9" | +384] © 59,768
44’ | 53°-38'| 46° 30' | -360|- 57,840
5a’ | 51° 49"| 44° 51" | -336|-" 55,912
6 | 49° 48") 48° 14" | +314) 58,984
22''| 479 54!) 41° 87'.| +292) 52,056
40" | 46° 2/) 40° 0’ | -270) 50,128
0’ | 44°.10'| 38° 24’ | +250) . 48,200
a ee ae re ee al ol old ole le we)
or
Go
oo
eR Re ee
(Jt)
i
lor)
Nore
ow
ot
oo
- Exampre.i—The apertures of four objectives, two, of which are. dry, one water-immersion, and one oil-immersion,
s ~ qwould be compared on the angulan aperture view as follows ;—106° (air), 167° (air), 142° (water), 130° (oil).
So Their actual apertures are, however, a8 >< sae - *80. “98 1:26 > 1°38 — or their
_ aumerical apertures. :
Pic Meo
de ee:
{enw
(8)
II. Conversion of British and Metric Measures.
, $3,
(1.) Linea. 4
Seale showing Micromiilimetres, §c., into Inches, §c. Inches, §¢., into mt
ane race ies M ins. mm, ins. | mm, ins, ue MO el *
hee 46 Titchibes 1 “000039 i “039370 5 2-007892 | ins, %
| “000079 ‘078741 2-047262 |> 3. 1-015991.
ee 3 000118; 8 ‘118111| 58 2°086633 | 5°2°° a
qe ane 4 +000157) 4. -157482| 54 2°126003 | —23°° 7.699318"
5 +000197| 5 196852 | 55 2°165374 | 17" 9+53997
aA 6 -000236) 6 -236223 | 56 2°204744 |. 22°" 9-899107 |
Ee 7 -000276| 7 “975593 | 57 2°244115 | 2°" 3.474979"
=n 8 000315) 8 314963 | 58 2+283485 | 2°? 3. gogRag:
E | 9 -000354|; 9 “354334 | 59 2322855 |. 722° g.agg9q%
Bie a 10 -000394| 10 lem.) -393704| 60 (6cm.) 2°362226] 24" 5.079954
Ale -| 11 -000433"| 11 433075 | 61 2401596 | ides 67349943
AG 12 -000472| 12 "472445 | 62 2440967 | sooo _ 8° 4660915
| 13 -000512| 18 “511816 | 68 2°480337 | ano 12°6998867
les 14 -000551| 14 551186 | 64 2°519708 | tooo 25°399772"
=& A715 +000591 | 15 °690556 | 65 _ -2:559078
[es 16 -000630| 16 “629997 | 66 2-598449 |
=a 17 000669 | 17 “669297 | 67 2°637819
lz | 18 -000709| 18 -708668 | 68 2°677189
oH 19 -000748 | 19 748038 | 69 2°716560
IE z| 20 :000787| 20 cm.) -787409| 70 (7 cm.) 2°755930
=
[Ee 21 -000827| 21 26779 | ‘71 2°795301
| 22 -000866| 22 *866150| '72 2° 834671
Es 23 -000906| 23 -905520 | 73 2- 874042
| 24 -000945| 24 “944890 | 74 2913412
es 25. -000984 | 25 “984261 | ‘75 2° 952782
HE 26 -001024 | 26 1:023631| ‘76 2992153
= 27 -001063 | 27 1:063002 | 77 3031523 ;
le 28 -001102) 28 1:102372| '78 *-3°070894 | 23°
= 29 +001142; 29 1°141743 | '79 8-110264 s.
E 30. -001181 | 80 (3cm.) 17181113} 80 (Som.) 3+149635 | 3°
E B1 --001220} 31 1:220483| 81 3°189005| ve
2 82 -001260| 82 17259854 | 82 3+228375 | as
lz 33 *001299 | 33 1:299224| 83 3:267746 | az
= 84 :001339:| 84 1°338595 | 84 3°307116 | zo
lz 35 :001378| 35 1°377965 | 85 3-346487| =
= 86 -001417| 36 1-417336 | 86 3°385857 | a
rE 37 -001457| 37 1456706 | 87 3*425228 | ae *
= 88. 001496} 38 1496076} 88 3°464598 | > ¥
E 89 001535 |. 39 1:535447 | 89 3503968 =
E 40 -001575| 40 (4om.)1-574817) 90 (9 cm.) 3-543339 | a5
= 41 -001614| 41 1°614188 |} 91 “.3*582709 .
(E 42 001654 | 42 1°653558| 92 3-622080 | 2.
= 48 -:001693| 48 1692929 | 93 ~ 8-6614501 4°
1B 44 -001732| 44 1°732299 | 94 3°700820 | 2.
Is E 45 -001772} 45 1:771669 | 95 3-740191 |. gs
= 46 -:001811)} 46 — 1°811040'} 96 3°779561 | ae
} E “47 .:001850| 47 1850410] 97 8818932]
= 48 -:001890; 48 1°889781| 98 - 4 3*858302 J. ota:
te 49 +001929| 49 1:929151, 99. ©" B:80767B Fg
= 50 ‘001969 | 50(5 cm.) 1-968522 | 100 (10 om.=1 decim.)| 2:
r [ 60 002362 peti * SS Re
lE 70. °002756. decim. ins, f Been
iis 80 003150 aed 3°937043. bet
lz 90 +003543 2 7874086 — ANS.
= 100 = * 003937 3 11°811130 ete?
IE 200 -007874| a -15°748173 sek)
= 300 -011811 5 19° 685216 epee
[ 400 | :015748 6 ‘23°622259 poe
a 500 | :019685 7 Q7°559302 ore
1} 600. +023622 8 31°496346 te
10004 =1 mm. || 700 *027559 9 35483389 oe
10 mm.=1 em. 800 :031496; 10 (1 metre) 39°370432 hu
=1dm. | 900 :035433 | | (= 8:280869 ft, .
=1metre.||1000(=1mm.) |) 0-2 1098623 yds
-
ecchch ete
£6GE SCP. os
aeces. ‘a1 D 0002 BS ;
C6FES + *ZO ¢.LSP “ILOAT “Sq] §
Paes m bemne See OOL. Som P8GEES-F = CIPS 1) $LG- LL] ‘ST[°3 160066- =
eae ELEGSe- “10 k :
Som = Pe qoae 0 ie Z99889-T OOL | > -sqund $zL092-1 =
C6RGLE-9 OL es (13.1) of res ape ‘J “quo eTgego. =
906TESS 6 FII6S8- 8 : Te : orgt Or
OTOEST.¢ 8 GLECFS GL 8 POOLEL-T OL | peo mL D ony
LE6SES -F be FP9GOS- OL By as is OEE ne
LEGLES«S 9 60F6SS-6 9 FLOIES: 6 : Lae Sa Sk a
seer ; ara} : épa¥e0-9 ae OFS GEEG19- 98 009
eae é en ee ee og |. ge9ste-08 _ 008
6968F6+T g L629 - OB saat 308. : a
6LE6G63-T i 0LF980«8 G GCELLG-G Ng | pn age ca abe
eee pega ae -souutasinep ay) Sova 167.4 LLOGOS- GL 006
s00Te8.¢ . 48 eee 8 6Eec0L-9 CTP 1) OOF
—~ 001g8-¢ 6: ; j Groloep 1) OUT sce O&60TS-T & ale ea
916881-S 8: LI6S888-T 06 POOLPL-T Res HORE TSS a8
o Lec? ap SSFeG-E 08 Se tee Seal LLITLG AS Ghee)
LE6L88-¢ 9. £9G080-1 FN a DL SA NOTES 56 2 Ruse ccriore SURES RODIN Leer, ae
— 8F6684:S ¢. 1F6G26- 09 ess eo a ee eee
SS6168-3 F: - 80- 6SFSEL- ee ey alt he SER os
LZ6SES-F LO. 96080T- nen aon Sree he eee Ske: :
LE6LE8.8. oe O80. F6S260- 9 PLOTES 6 ae: Oe eee a Reo
St668S-E cO. Z9TLLO- —g _ TIgs6l-8 Sus ae Rae coe:
SE616S-Z Lo BO. We GELTIO. 82x eels 6F9FGE-9 as enc to
696EF6-T mn e0e te LEZOFO- g : E86516-7 tee Sadopate aie
cae ene Aa i as qoseeact. ore code Sep eSOOMOO! «5 Fe a
Se a it a ce 3 Bate Me “sotumersiy || SOUT UE ‘sur, rejoins al Pas $SOp'qno > ee > ROUTE
ae ‘souaunabogi Onur “0.6 ‘suipap Op ‘sump oyun “08 Snag: °f ‘oom ie “98 err ong.
“aura mn & g)
2p ‘Ssoyoug ongng: “opin ro ‘Sogn 3
(10) Eee
III. Corresponding Degrees in the
Fahrenheit and Centigrade
Scales.
See :
YMNOHWeOorR
oo
ive}
iw)
od . . . -
HOG PNOLANWHAAPD ONAIWH DD
eS seb OO 02 CO SIH bo ARWwWroOon
PER ett apt
oo
onaOownl
~ #06
SWORN OK
PoANWaAHKS
DNOSRODNWHHOANHDHOAWHHSANW
~ 104°0
or 43) to 70° 3
Phosphorus See hs 65°. 47
Bisulphide ef carbon apa, Sam
Flint glass ~ : 5° 30! to 58° 8 9
Crown glass — 56° ou 40. ie
Rock salt 5
Canada balsam
- Pure water
(Airs
IV. Refractive Indices, Dispersive ©
Powers, and Polarizing ©
Angles. Se
(1.) Rerractive INDICES. -
= € Mean values.) — i
Diamond 2-44 to 2° 735 S
Phosphorus ages 7 224 ©
Bisulphide of carbon Soret 678
1-576 to 1" 642
1°531 to 1° 563” bY
Flint glass
Crown glass
Rock salt
Canada balsam
Linseed oil (sp. gr. * 982)
Oil of turpentine (sp. gr. +885)
Alcohol 1-372
Sea water pean 1-343
Pure water Ls "336
Air (at 0° C. 760 mm.) A: Bsa Si
WwW
(2.) DisPERSIVE POWERS.
Diamond
Phosphorus
Bisulphide of carbon
Flint glass
Crown glass
Rock salt
Canada balsam
Linseed oil (sp. gr. *932) pes
Oil of turpentine (sp. gr. Ss: +048
Alcohol 10 29.
Sea water Bane fc
Pure water : ees ifs
Air Es ae
G3.) POLARIZING ANGLES.
Diamond
Linseed oil (sp. Bt. 982), SF
Oil of turpentine (sp. gr. oe Sepak
Alcohol eer
Sea water
vs
( ll)
V. Table of Magnifying Powers.
id ed petit vs ee, and 7. more than the figures given in this column.
oe Pee and Lealand’s No, 2—= 7°4, and Beck’s No. 2 and Ross’s B = 8 magnifying power, or
SEES. EYE-PIECES.
Beck’s 2,
Beck’s 1, | Powell’s 2, Beck’s 4, Beck’s 5
Powell’s 1, and Powell’s3,| Ross’s C, | Beck’s 3. Powell’s 4,1 Ross’ a E Powell’s 5.§ Ross’s F.
Ross’s A, | Ross’s B, Ross’s D.
nearly.*
be é Foca Lreneru,
Sate: [o}
a3 E gia. | tim, | Lin | tin 2 |: | ie lj
a2 A 3 in, 5 6 3 in x in To 12 3 in. ~ in.
: 2 E ’ MAGNIFYING POWER.
8 be
ee lg | 7, | 10 | 121 | 15 | 20 | 25 | 30 | 40
si! on AMPLIFICATION OF OBJECTIVES AND EYE-PIECES
co oes COMBINED.
bo 2 10 15 20 25 30 40 50 60 80
4 24 123 182 25 314 374 50 623 75 100
3 82 ~ 162 25 332 412 50 662 835 100 1334
2 5 25 37k 50 624 75 100 125 150 200
4% |. 62 331 50. 662 83 | 100 1331 | 1662 | 200 2662
14. 10 50 75 100 125 150 200 250 300 400
8}. 123 623 932 feet oe 1562 | - 1873 250 3122 375 500
2 134 662 100 1331 | » 1662 200 2662 3334 400 5334
75 1124 150 1874 225 300 375 450 600
100 150 200 250 300 400 500 600 800
125 1872 250 3124 375 500 625 750 1000
e150 225 - 800 375 450 600 750 900 1200
1662 250 3831 4162 500 6662 8332 | 1000 13332
200 300 400 500 600 800 1000 1200 1600
250 375 900 625 750 1000 1250 1500 2000
300 450 600 — 750 900 1200 1500 1800 2400
850 525 700 875 1050 1400 1750 2100 2800
400° 600 800 1000 1200 1600 2000 2400 3200
450 675 900 1125 1350 1800 2250 2700 3600
500°. 750. 1000 1250 1500 2000 2500 3000 4000
550 825 1100 1375 1650 2200 2750 3300 4400
600 900 }- 1200 | 1500 1800 2400 3000 3600 4800
650 975 1300 1625 1950 2600 3250 3900> 5200
700 1050 1400 1750 2100 2800 3500 4200 5600
750 1125 1500 1875 2250 8000 3750 4500 6000
800. | 1200 1600- 2000 2400 3200 4000 4800 6400
850 1275 1700 2125 2550. 3400 4250 5100 6800
.- 900 1350 1800 2250 2700 3600 4500 5400 7200
950 1425 1900 |. 2375- 2850 83800 | . 4750 5700 7600
1000 4 1500 2000 2500 8000 4000 5000 6000 8000
1250 1875 2500 8125 3750 5000 | 6250 7500 § 10000
O lf 1500 2250. | 3000 3750. | 4500 4 6000 7500 9000 | 12000
2000 3000 4000 5000 6000 8000: 4 10000 | 12000 } 16000
Oj} 2500 3750 5000 | 6250 7500 §¥ 10000 | 12500 | 15000 | 20000
| 3000 4500 6000 7500 | 9000 4.12000 {| 15000 | 18000 | 24000
4000 6000 8000 | 10000 | 12000 16000 4 20000 | 24000 } 32000
( 12)
HENRY CROUCH'S
LAD, First-Class Microscopes.
Student’s Microscope.
New Family and School
Microscope.
Wew Series of Objectives.
New Accessories.
NEW ILLUSTRATED CATALOGUE, ON RECEIPT OF STAMP, MAILED ABROAD FREE.
HENRY CROUCH, 66, Barbican, London, B.C,
AGENTS IN AMERICA, é
“JAMES W. QUEEN & CO., 924, Chestnut Street, Philadelphia, U8.
JOURN. R.MICR. SOC. SER. II. VOL. IL PL.1
haat
West Newman & C? bith
A.D. Michael ad not. del.
8 1—5.
6-9
ocellatus
Scutovertex maculatu
Cepheus
JOURN. R. MICR. SOC. SER. I. VOL. I. PL.I.
West, Newmar £ C° lith
6.
ipes 1-5.
otaspis lacustris
-
a:
Dameeus monil
N
JOURNAL
OF THE
ROYAL MICROSCOPICAL SOCIETY.
FEBRUARY 1882.
TRANSACTIONS OF THE SOCIETY.
eet
1—Further Notes on British Oribatide.
By A. D. Micwazt, F.L.S., F.R.M.S.
(Read 14th December, 1881.)
Puates IL. anp IL
Since my last communication to this Society, I have continued my
observations upon the life-histories, and general habits of the
native species of Oribatidz, and also my collection of these minute
EXPLANATION OF PLATES I. ann IL
Pate I.
Hie. 1—Scutovertex maculatus, adult. x 100.
>, 2-—The same, nymph.
» 9o—The same, adult; a, stigma; 6, stigmatic organ. x 370.
» 4.—The same, adult; a, portion of maxillary lip; 6, palpus. x 3760.
» o.—The same, adult; mandible. x 370.
s 6.—Cepheus ocellatus, adult. x 80.
5», %—The same, nymph, nearly full grown; showing larval and two
nymphal cast notogastral skins, the bordering scales of the
existing skin not haying yet passed far beyond those of the
former skin.
5 8.—The same, adult; a, stigma; 6, stigmatic organ; c, wing of the
tectum ; d, terminal spine of same; e, hair set in at commencement
of spine; f, portion of the tectum. x 170.
» 9.—The same, adult; the mandible. x 370 (reversed).
Puate IL.
Hic. 1.—Dameus monilipes, adult. x 160.
» 2,—The same, nymph, full grown; showing the larval and two nymphal
cast notogastral skins.
5, ¥3.—The same, adult; a, stigma; 6, stigmatic organ. x 350.
» 4,—The same, adult; a, portion of maxillary lip; 6, palpus, with 5th
joint reflexed. x 450.
» 9. —The same, adult, Ist leg; a, coxa; 6, trochanter (so called); c, femur
(so called); d, enlarged tibia ; e, tactile hair on same; f, tarsus;
g, monodactyle claw.
» 6.—WNotaspis lacustris, adult. x 105.
5, %.—WNotaspis licnophorus, adult. x 180.
4, 8.—The same, adult; a, stigma; }, stigmatic organ, x 570.
Ser. 2,—Vok. II. B
2 Transactions of the Society.
creatures, with a view to making our fauna more generally known. ~
It is the experience of every one entering upon an almost untrodden
path in natural history, or indeed in any other science, that at first
new species and new facts accumulate rapidly and easily, while,
after a time, novelties, whether of observation or of species, are more
difficult to find and more laborious to follow out. I am not an ex-
ception to this rule, and naturally I cannot record the number of
additions which I was able to make in my former papers. My
searches have, however, been rewarded by finding species which I
believe to be not only new to Britain, but entirely unrecorded any-
where, and which are far too numerous to be figured in the neces-
sarily and properly limited number of plates which the kindness of
this Society can place at my disposal. I do not think that written
descriptions of creatures of this nature are of much real service
without drawings, as, after all, words are but a vague way of
identifying form upon which so much depends. I also think that
drawings, to be of use to other naturalists, must be upon a sufficient
scale to show detail, particularly with such organisms as the
Oribatidx, where specific distinctions depend greatly upon the for-
mation of the essential parts of the cephalothorax, which in itself
is frequently very small in proportion to the abdominal region. I
have therefore thought it best, in this paper, to describe and figure
a few of the more interesting unrecorded species with, I hope, some
degree of exactitude, rather than to figure a larger number upon a
scale which might possibly not be sufficient for identification
hereafter.
Before proceeding to notice the unrecorded species, I will deal
with such further observations as I can place before you relative to
the habits, &c., of this family of Acarina.
Deposition or Protection of the Ova.
Tt will be found, by those who read works referring to this sub-
ject, that a great number of naturalists broadly state that the
Oribatide are viviparous. I am not quite sure where the idea
originated ; some suppose that Claparéde is responsible for it, but I
fail to find anything in the writings of that excellent observer
which in any way justifies the accusation. His only work treating
of any of the Oribatede, as far as I am aware, is his chapter on the
development of Hoplophora contractilis (as he calls it), in his
‘Studien an Acariden,’ and in this he expressly says that the idea is
erroneous. It is not of much importance where the suggestion
came from, but it is more worthy of remark that it has found its
way into the works of some of the ablest and most accurate writers,
who of course did not take it, or profess to take it, from their own
observations, but simply on the authority of others; thus, for
Further Notes on British Oribatide. By A. D. Michael. 3
instance, Huxley,* talking of the Acarina, says: “Most are
oviparous, but the Oribatide are viviparous.” This statement, in
spite of the high authority for it, is certainly an error, although
there may be a few exceptional instances of it, as will be seen later
on in this paper, but those instances are, as far as I am aware,
recorded here for the first time. The impression which has got
abroad among naturalists, and held its ground so tenaciously, is,
perhaps, the more curious, because Nicolet, the principal author who
has written upon the Orcbatidz, says that the egg is deposited, and
that the larva emerges very shortly afterwards, and this dictum of
the French acarologist, in my opinion, correctly states what really
occurs in a great many, and probably in the large majority of
instances,
The result of my own observations has been to convince me that
the matter is not quite so simple as naturalists have supposed, and
that it is not possible to lay down one general rule which will be
correct in all cases; indeed, this remark is applicable to most ques-
tions connected with Acarina. I have usually found that if I have
attempted to generalize from a few known instances the rule which
I thought I had found has broken down, and I have also found that
a great number of the general laws enunciated by other observers
fail to stand the test of a wider experience.
It seems to me that there are at least three if not four modes by
which the eggs are brought to maturity, and the larve hatched, in
different species, or under different circumstances.
The first method is that so well known in insects, that the egg
is deposited in a fertilized but only slightly developed state. The long
ovipositor, or extensile oviduct, of the female Acarid is used for this
purpose, and the egg is placed in crevices of the wood, moss, or
fungus, upon which the larva will feed ; the egg adheres, either by a
certain viscid quality in its exterior envelope, or more often is
attached by a few threads of silk-like substance. Segmentation may
have gone on in the egg to some extent before deposition, but very
little progress has been made towards the differentiation of any in-
dividual parts of the future larva. A very considerable time often
elapses between the deposition of the egg and the hatching of the
larva in this mode, and I think that the creature probably often
passes the winter in the egg state, and is only hatched on the
approach of spring. I have frequently had the eggs myself for a
long time before hatching in various species, as, for instance,
Dameus geniculatus, D. clavipes, Nothrus theleproctus, &e.
The second mode is that which Nicolet apparently considered to
be universal, and which I myself believe to be the most frequent,
particularly in full summer. ‘This is, that the development of the
* A Manual of the Anatomy of Invertebrated Animals.’ London, 1877,
p- 383.
B 2
- Transactions of the Society.
egg is almost completed within the body of the living mother, and
that the egg is extruded, certainly as an egg, as in the first method,
but with the larva so fully developed that it escapes from the ovum
very shortly after deposition.
I have a strong suspicion that a third mode, only to be found
in exceptional instances, is that which Huxley states to be charac-
teristic of the family, viz. that the female is viviparous or ovo-
viviparous. This, if it occur at all, is probably not the case at all
seasons of the year, even in the species where it may take place
during the period of most rapid reproduction. I have not any
proof or certainty that this mode ever exists, for I have not ever
witnessed the birth of a living larva, unenveloped in any egg-shell,
from any of the Oribatide, but I have dissected out of the body of
a female, either living, or killed immediately before, a larva, which,
although not sufficiently strong or active to run, has been fully de-
veloped, and able to kick its legs and move its trophi in a very
vigorous manner, and exhibit other signs of life. In addition to
this, I have several times found larve in a cell where I had kept a
pair of adults, and which I had carefully examined for ova a short
time before without detecting any. I do not place much reliance
upon this last reason, as the ova are sometimes extremely difficult
to find in consequence of their smallness, their want of colour, and
the places in which they are laid; but, as far as it goes, it is in
favour of the occasional viviparous theory.
In the above-named three methods only one, or at the utmost
two eggs are matured at one time; the reason for this 1s evident
enough, as the egg is so large as to appear disproportionate to the
size of the body, and many could not be ripe at once consistently
with the life of the Acarid.
I believe that the fourth method has not hitherto been
recorded by any observer, and it appears to me interesting, I
have noticed it chiefly in the case of Oribata globula, but it pro-
bably exists in other species. It is as follows: The female,
instead of maturing only one or two eggs at the same time,
matures a much larger number, often a dozen or more, so that the
abdomen appears to be entirely filled with them; these eggs are
not laid, neither do they hatch within the body of the living
mother, but the mother dies with the abdomen distended by fully
formed eggs, in which the larve have not been developed. The
whole contents of the abdomen except the eggs seem to dry up
and disappear, leaving the chitinous shell of the parent as a pro-
tection to the ova. This condition of matters often lasts for a
considerable time, indeed I believe that Oribata globula often, or
usually, passes the winter in this state. When the larvee are at
length hatched, they escape by the opening of the camerostomum,
the labium having probably dropped off, or by the genital or anal
Further Notes on British Oribatide. By A. D. Michael. 5
opening, the folding doors which close these respective apertures
having also dropped off. Sometimes the apertures are so small, or
the larvee so large, that they cannot easily escape by the apertures,
-and I have more than once had to assist those I had bred in
confinement by breaking away the shell.
Dr. G. Haller, of Bern,* lately recorded the finding of
numerous dried exo-skeletons of Hoplophora in winter among
the fallen leaves, each shell having a large single mature egg in it.
Haller concludes that the female Hoplophora, when about to
deposit an egg, seeks for the exo-skeleton of some deceased member
of its own species, and uses it as a shelter for the ege. It is of
course quite possible that this may be so—I cannot deny it—but, as
Haller does not appear to have seen the egg laid, and he was
hardly likely to have done so, as the Oribatedz object to light, I
cannot help thinking that this is probably another instance of the
fourth method above described, with the distinction that here only one
egg is matured at once. If it be not so, it is odd that the Hoplo-
phora should always choose the exo-skeleton of a Hoplophora
instead of distributing its favours more generally amongst other
genera.
Deutovum Stage.
Another observation which I have to record, is relative to the
development of the egg after extrusion. The eggs of some
Oribatide are of a rather leathery consistency, those of other
Species are provided with a hard chitinous shell, which is brittle
‘and non-elastic. Claparéde, in his ‘Studien an Acariden,’ records
the occurrence, in the ova of Ata bonziz, of what he calls a
deutovum stage; Megnin has observed a similar thing in the case
of Trombidium fuliginosum, and I myself noticed it in the ova of
other Trombiduidz, but I am not aware of any one having observed
it amongst the Oribatide. I have now to record that it decidedly
is equally a portion of the life-history of some, but not of all,
members of this family. The deutovum stage is as follows:
When the exterior shell of the egg is hard and non-extensile, the
gradual increase of volume in the egg-contents produces so much
pressure from within upon the shell that the latter splits sharply
all round its periphery, dividing it into two somewhat boat-shaped
halves; the inner membrane which lines the shell has in the
meantime increased in strength, and has become the true en-
velope. The space between the two broken halves of the exterior
shell is at first a mere line, but, as the contents increase, this line
widens, and the halves of the old shell get pushed further and
further apart, showing a broad white space (the inner membrane)
* “Miscellanea acarinologica,” MT, d. Schweiz. entom, Gesellschaft, 1879,
No. 4, p. 502,
6 Transactions of the Society.
between them. It is along this line that the rupture takes place
when the larva escapes, as recorded in my first paper on the
Oribatide in this Journal.*
Wood-boring Species.
Claparéde, in his ‘Studien an Acariden,’ records the result of
his excellent observations on Hoplophora in its immature stages,
his discovery that the larvae and nymphs were wood-boring
creatures, and he expresses his astonishment at finding that the
nymphs and larvze were soft white creatures, when the adults are
so hard and dark; he calls it passing through an Acarus stage. I
find that Hoplophora is not by any means an exceptional instance
in either of these particulars. The nymphs of Hermannia arrecta,
Tegeocranus elongatus, Cepheus vulgaris, and some others, live in
dead wood, which they perforate with long burrows in all direc-
tions, until the wood is often thoroughly riddled by them, only the
thinnest partition being left between the burrows. The larva or
nymph, as the case may be, is usually found at the end of the burrow
furthest from the mouth, being in fact the last place which it has
worked to; the burrow behind it is usually filled with excremental
matters and wood-dust. The nymph of Tegeocranus coriaceus
burrows into the more solid fungi in exactly the same manner,
and there are doubtless other boring species which I have not yet
traced. It is rather interesting to observe that, in all of these
instances, the larvee, or nymphs, are soft, white creatures, entirely
without the defensive armour or other protection possessed by
members of the family which are more exposed to danger than
these sub-cortical species.
Eedyses of Leiosoma palmicinetum.
Those who have seen the beautiful nymph of Leiosoma
palmicinetum, which is figured in a former paper of mine in this
Journal,t will not readily forget it. I was curious to see how the
very large Japanese-fan-shaped, membraneous hairs, which form
a broad border round the abdomen of the nymph of this species,
were disposed of during the formation or ecdysis. I had naturally
imagined that they would be folded up, either by closing the
nervures together like a fan, or else transversely like the wings, &c.,
of insects. The extremely simple and pretty method by which
nature effects the packing did not strike me. The elegant mem-
braneous hairs grow on the edge of the body, and are formed fully
expanded ; instead of being doubled up, their peduncles are simply
turned down a little, so that the palmate hairs lie flat against the
ventral surface of the Acarid, and are thus protected from injury ;
* Vol, IL. (1879) p. 225. + Vol. IIE. (1880) Pl. III.
——
Further Notes on British Oribatide. By A. D. Michael. 7
the two pairs of immensely long setiform hairs, which spring from
the edge of the abdomen, are also bent down upon the ventral
surface, instead of being folded, and there form a diagonal cross.
The whole arrangement may be most distinctly seen through the
existing skin, pending one of what, for want of a better name, I
call the inter-nymphal ecdysis, i.e. a change of skin which does not
take place upon any transformation, but simply upon the nymph
growing larger. I have luckily succeeded in mounting a specimen
in this condition which shows the whole arrangement admirably.
I have not figured it from want of space.
New Species.
Among the unrecorded species described and figured below are
one or two which may be worthy of some remark, although I have
not any very striking novelty to record this time.
In my paper published in the third volume of this Journal,
page 186, at the end of the description of the nymph of Leiosoma
palnucinctum, I stated that I had brought home what I had
supposed to be several very young specimens of that nymph found
upon the golden lichens growing upon the rocks of the Land’s
End, but that, when examined with a higher power, they turned
out to be a different species, the shape being slightly longer, and
the nervures of the palmate hairs irregularly furcate instead of
reticulated. I also stated that they had not attained the adult
condition, and that I doubted their surviving the winter; that
doubt became considerably stronger as the winter advanced, for my
captives became to all appearance dead, and I feared that the only
thing to be done with them was to mount them as specimens. I
was still unwilling to abandon a hope, however remote, of tracing
the species, and my patience was in this case rewarded, for, as the
spring advanced, the apparently dead nymphs began to move about
very slowly, and finally underwent their last transformation, and
there emerged an adult, which was new to me, and I believe
unrecorded, and which was moreover quite distinct from anything
I had seen, and was a handsome species. The interesting part
was, however, that, although the two nymphs resembled each
other so closely that it required a careful examination with a
moderately high power to find out the difference, and although
they were utterly different from all other known nymphs, and
notwithstanding that they came from the same place and both fed
upon lichen, yet the imagos were quite dissimilar, and not in any
way to be included even in the same genus. Palmicinctum is a
Leiosoma, and the present species, although it does not fit very
well into either of Nicolet’s genera, yet is certainly a Cepheus,
unless a new genus were made for it, which does not seem to me to
8 Transactions of the Society.
be desirable. I have called it ocellatus from the curious effect, like
two great eyes, produced by the globular stigmatic organs (or
protecting hairs as Nicolet calls them) being sunk exactly in the
mouths of the stigmata. This is the only instance of such an
arrangement which I am aware of in the Oribatidz.
Another somewhat singular creature is the very minute being
which I propose to call Notaspis lienophorus: here again the
peculiarity is in the stigmatic organs, which are flattened, and so
large as to appear quite disproportioned to the Acarid. When I
have had this tiny creature alive on the stage of the Microscope
for the purpose of observing or drawing it, I have seen the
stigmatic organs blown about by the wind.
A third very curious new species is the one I propose to call
Damzus monilipes: the remarkable part of this creature is the
form of the legs, particularly the first pair, where the tibia is a
globular mass which appears altogether too large for the Arachnid,
and gives it the effect of carrying a mace on each side.
A fourth curious species I propose to call Notaspis lacustris :
the peculiarity is its being strictly aquatic, and being often found
covered with diatoms.
In conclusion I may briefly allude to certain slides which have
been in circulation of late as being mounts of an Acarus supposed
to feed upon the Phylloxera; those that I have seen have been a
collection of various Acarina, of different families—in fact anything
and everthing found upon a vine; amongst them were more than
one of the Oribatide. I think that such information should be
received with extreme caution, as I am not aware of any well-
authenticated instance of any species, which really belongs to this
family, being habitually predatory.
Descriptions of Species.
CEPHEUS OCELLATUS n. sp. Pl. I. Figs. 6-9.
Average length about *6 mm.
“3 breadth ,, ‘32 mm.
8 length of legs Ist, 2nd, and 3rd pairs about *24 mm,
” ” 9 4th pair about *32 mm.
This species does not fit very happily into any of Nicolet’s genera,
but I do not think it is desirable, at present, to create a new genus
for it. The only one of the existing genera in which it can be
included is Cepheus, and in that genus I accordingly place it
provisionally.
It is a somewhat singular, and very well marked species. The
colour is very dark brown, often almost black, and the texture is
dull, without the slightest gloss.
The cephalothorax is rather more than a third of the total
Further Notes on British Oribatide. By A. D. Michael. 9
length, broad, and flat. The rostrum blunt, the tectum large and
well marked, its wings (or lamella) very large, nearly on edge, and
projecting far beyond the anterior edge of the horizontal surface of
the tectum; at their anterior termination these lamelle are trun-
cated and slightly rounded, from the lower angle of the truncated
edge springs a stout spine, which curves forward and downward,
and almost touches the tip of the rostrum. A little above this
spine, on the same truncated edge, is a much thinner but rather
longer spine, or hair, almost parallel to the thicker one. Hach
lamella increases in width as it nears the abdomen, and terminates
suddenly, with a rounded shoulder, just in front of the stigma.
The stigmata are placed at the junction of the cephalothorax and
abdomen, they are very large and open: the opening faces straight
upward. The stigmatic organs (or hairs) are globular, and are
gunk in the mouth of the stigmata, which gives each stigma the
appearance of being an enormous eye—it is from this effect that I
have named the species. This peculiarity alone would be sufficient
to distinguish the present species at a glance from every other
which I am ‘acquainted with. The interstigmatic hairs are short
spines just inside the stigmata. The palpi are subcylindrical,
with the first joint much the longest, the third and fourth very
short, the fifth conical and densely haired, labium longer than
broad, mandibles very small.
The legs are stout, all joints except the tarsi very rough and
irregular in outline, the second joints much the thickest, the tarsi
short and stout. The first two pairs reach considerably beyond
the rostrum, the fourth pair only slightly beyond the posterior
margin. ‘The tarsi are clothed with numerous very thick hairs,
the other joints have very few hairs on them.
The abdomen is oval, truncated anteriorly, with the antero-
lateral angle produced so as to form short points projecting
forward and almost touching the stigmata. There is a broad
flattened margin, somewhat raised towards the edge, all round
the abdomen, except where it joins the cephalothorax; this band
bears a row of blunt spines, not quite regularly arranged ; inside
the band the notogaster is arched, but not very strongly; it is
divided by ridges into irregular strips or bands, of which one or
two run nearly parallel to the anterior margin and the rest run
more or less longitudinally. There are usually about ten bands in
the width ; each band contains two rows of round pits, the position
of the pits being alternate, i.e. the pits in one row come between,
and not opposite to, the pits im the adjoming row. The anal
plates are very large, and the genital plates are close to them;
both sets are sub-oblong in form.
10 Transactions of the Society.
The Nymph.
This is so similar to the nymph of Leiosoma palmicinctum * that
I think it will be convenient to poimt out the differences rather
than to describe the whole creature again. The present species is
a rather longer and narrower elliptical form than palmicinctum.
The beautiful expanded membraneous hairs, each shaped like a
Japanese fan, which form a broad border all round the creature in
both species, are similarly arranged along the lateral and posterior
margins of the abdomen in both species, but in palmicinctum they
also run round the anterior margin, entirely covering up the
cephalothorax. In the present species they are absent from the
anterior margin of the abdomen, but they complete the elliptical
border of hairs by running round the margin of the cephalothorax
itself, and a similar hair on each leg of the first pair completes the
border below the rostrum. This hair is absent in the nymph of
palmicinctum, but is present in the larva of that species. The
result of this arrangement is that the cast notogastral skins borne
on the back of the nymph have not any expanded hairs along
their anterior margins, paliicinctum has. ‘There are three pairs of
similar hairs, but longer and more pointed in form, down the
centre of the notogaster, being in fact upon the notogastral
portion of the cast larval skin. Another very leading distinction
between the two species is that in palmicinctum the nervures of the
expanded membraneous hairs are reticulated, whereas in ocellatus
they are irregularly branched.
The stigmata and stigmatic hairs (or organs), which are hidden
in palmicinctum, are present and conspicuous in ocellatus ; the organs
are somewhat lancet-shaped. Another great difference is the
entire absence in the present nymph of the four immensely long
hairs which project round palmacenctum.
In other respects than those above named the same description
would serve for both species, although the adults are so different.
I have only found the species upon the yellow lichens which
clothe the granite rocks of the Land’s End, Cornwall; it is not
common even there.
Noraspis LicnopHorvs,| ”. sp. Pl. II. Figs. 7, 8.
Average length about *19 mm.
Ae breadtits, =) alice.
Me length of legs, Ist and 4th pairs, about -1 mm.
ai s
” ” ” r ” ” ”
* Described in this Journal, iii, (1880), p. 184.
+ Arxvoy, a fan; pepw, I bear.
Further Notes on British Oribatide. By A. D. Michael. 11
This extremely minute species is principally distinguished by
the disproportionately large size and unusual shape of the stigmatic
organs, from which I have named it.
The colowr is light yellow-brown, and the whole dorsal surface
is highly polished.
The cephalothoraz is considerably narrower than the greatest
width of the abdomen, but at the actual point of juncture the
cephalothorax is slightly the wider, and is partially hidden by the
advancing anterior point of the latter. There is a small central
point to the rostrum, which then has a very obtuse angle, and,
after attaining nearly its full width, becomes more parallel-sided.
The cephalothorax widens suddenly at the anterior edge of the
tectum, which projects beyond the lateral margin of the rostrum.
The central portion, or tectum proper, although attached to the
cephalothorax by its whole surface, has the position of the lamellz
marked by two strong ridges joined by a transverse ridge anteriorly,
and also joined posteriorly, not far from the abdomen, by another
ridge, not straight, but forming three angles, the central pointing
backward, and the two lateral ones pointing forward ; after these
join the ridges which represent the lamelle, the two united ridges
turn sharply inward to escape, and border, the inside of the
stigmatic elevation. The stigmatic organs are of moderate length,
very broad, and flattened out, and resemble the Japanese or Indian
fans, only that the distal margin is slightly wadulated; these
organs are marked with lines of elevated dots, and from their large
surface they are blown about a little by the wind.
The legs are of moderate length, the second joints very thin at
their insertion, but suddenly, and much enlarged, narrowing again
somewhat at the distal end; the third joints very small and fine ;
the tibize wineglass-shaped, much enlarged at the distal margin ;
the tarsi short and stout, the triple claws very heterodactyle. 'Vhis
latter point, according to Nicolet’s definition, would prevent the
creature being included in the genus Notaspis. ‘The tibie of the
first pair of legs have the tactile hair long, the tarsi have numerous
fine hairs, and there are one or two short spatulate hairs on each of
the other joints of each leg.
The abdomen is elliptical, pointed anteriorly and posteriorly, the
anterior point being the sharpest. ‘There is a close row of short,
curved spatulate hairs round the margin, and two longitudinal
rows of about three similar hairs near the centre of the
notogaster.
I have found the creature in decayed wood at Tamworth, in
Warwickshire, and at Epping Forest; it isnot common. I believe
it to be unrecorded.
12 Transactions of the Society.
Nymph.
The nymph of this species so closely resembles the perfect form
that I do not think any one would mistake it. I therefore have
not figured it, and only give here the differences from the perfect
form (beyond the ordinary one of being monodactyle instead of
tridactyle).
The colour of the nymph is pure milky white, without a speck
of darker marking about it.
The general thickness of the legs is greater in the nymph, and
the shapes of the respective joints are not so varied.
The markings figured upon the cephalothorax of the adult are
not found on the nymph.
The hairs bordering the abdomen are rather smaller in the
nymph than in the adult.
The skin is covered with slight wrinkles or vermiform markings
instead of being polished.
Noraspis Lacustris, ». sp. Pl. II. Fig. 6.
Average length about *5 mm.
3 breadth ,, ° A;
is length of legs, Ist pair, about *26 mm.
” 3 4t ” » 4 by
I have ventured to include this species in the genus Notaspzs,
although this is a monodactyle species, and Nicolet defines the
genus as tridactyle; but I have come to the conclusion that,
although it was perfectly natural for Nicolet, working from the
species he was acquainted with, to take the number of claws as dis-
tinctive of genus, yet there are some genera in which this cannot
be supported as a good characteristic.
This species is strictly aquatic, but is not a swimming creature ;
indeed, none of the Oribatide are. It crawls about the subaqueous
plants, and is confined to fresh water. It is often found covered
with diatomacese, which adhere to it sufficiently tightly to be
preserved upon it. '
The colour is dull reddish-brown ; the texture is smooth but not
polished.
The cephalothoraz is less than half the length of the abdomen,
and forms a broad, short cone, with a slightly rounded apex; it is
considerably rounded at the posterior angles. The base is almost
as wide as the anterior margin of the abdomen. ‘There are not any
markings on the dorsal surface, except two short ridges, which are
doubtless the homologues of the wings of a tectum, but otherwise
that part is absent. The stigmatic organs are not visible, and
there are not any interstigmatic hairs; the rostral hairs are short
and curved.
Further Notes on British Oribatide. By A. D. Michael. 13
The legs of the first two pairs are set in deep clefts of the pro-
jecting lateral portions of the sternum; they have a tendency to
set outward. The second and fourth are the principal joints, the
tarsi being short and thick. Hach tibia bears a long tactile hair ;
the tarsi have numerous fine hairs, and the other joints, except
the coxee, mostly have a few longish, fine hairs, chiefly arranged in
whorls.
The abdomen is a short ellipse, not far from a circle, and is very
slightly truncated posteriorly. This truncated portion bears
two pairs of short, fine hairs, the inner pair being the longest.
I believe I know the nymph of the species, but as I have not
actually bred it I refrain from describing it.
The species is common and generally distributed.
ScUTOVERTEX MACULATUS,* 7. sp. PI. I. Figs. 1-5.
Average length about ‘54 mm.
. breadth ,, ‘30 ,,
. length of legs, Ist and 4th pairs, about °33 mm.
9 ” 2nd ” 3rd ” ” 30 ”
The colowr both of body and legs is dark brown, almost black ;
the whole dorsal surface is thickly sprinkled with raised dots.
These are irregular in shape, and in scattering on the cephalo-
thorax, but on the abdomen, which constitutes by far the larger
portion of the creature, they are more even in size and arrangement,
being closely packed, and more or less approaching round or
subsquare. Towards the lateral and hind margins of the abdomen
these dots form lines of dots radiating from the centre of the body,
along the front margin they are transverse in arrangement, and
in the centre they are irregular, or form labyrinthine lines. These
dots projecting make the edge, or any part seen against the light,
always appear rough.
The shape of the creature is an elongated ellipse, being nearly
twice as long as broad.
The cephalothoraz is broad and rather large, but is greatly
overhung by the anterior margin of the abdomen, which hides a
large part of it. The extreme tip of the rostrum is small and
rounded, and bears a pair of hairs. From thence the cephalothorax
widens suddenly, and becomes much arched, and again widens
somewhat suddenly at the insertion of the first pair of legs. There
is a tectum very conspicuous, but short and narrow, and without
lateral wings, or rather the edges are thickened, slightly raised,
and then turned downward, giving an appearance of being
attached to the cephalothorax by their whole circumference.
From about the middle of the internal edge of the lateral ridge
* Maculatus, spotted.
14 Transactions of the Society.
of the tectum, on each side, another ridge starts and runs backward
at an angle, so that the two together form a V-shaped marking, the
point of which is rounded, and lies within an indented semicircle in
the anterior margin of the abdomen. The elevated markings on
the tectum form transverse wavy lines. There is a strong chitinous
projection from the side of the cephalothorax between the second
and third pairs of legs. The stigmata are near the lateral margin
between the first and second pairs of legs. The stigmatic hairs
are short, and consist of a small globular head, on a stout filiform
peduncle. There are two pairs of short, thick hairs on the dorsal
surface of the cephalothorax.
The coxz of the first two pairs of legs are hidden beneath the
body. The trochanters of the same pairs are large and long, but
suddenly become small, and turn almost at right angles near their
insertion into the coxee. The coxe of the third and fourth pairs of
legs are rounded and conspicuous. ‘The second and fourth joints
are the longest in all the legs, the third joimt being the smallest.
The first three joints in each leg are covered with irregular raised
markings. ‘The tarsi have a few fine hairs round the claws, which
are very heterodactyle. There are three short, thick hairs on the
fourth joint of each leg of the first two pairs, and a few other
similar hairs on the different joints of the legs. All these hairs are
very caducous.
The abdomen is elliptical, slightly pointed posteriorly, and
slightly truncated anteriorly ; it is indented between the insertion
of the third pair of legs and the stigma, and the anterior margin is
cut out in rather more than a semicircle. This indentation receives
the point of the V-shaped ridge on the cephalothorax; and at the
side of it the anterior margin of the abdomen is attached to the
upper surface of the tectum. There are about ten short, thick
hairs round the hind margin of the abdomen, also very caducous.
On the ventral surface the genital plates form almost a square,
and are far forward. Theanal plates are large, elliptical, and touch
the posterior margin. i
Nymph.
The colour of this curious nymph is dull opaque brown, often
with a shade of dark olive green in the brown. It is so broad and
flat in general shape as to give the effect of having been
flattened out, and it is thickly covered with wrinkles and ridges all
over.
The cephalothoraz is flat, long in proportion to the abdomen,
but not in proportion to its breadth, conical, but sharply excavated
at the edge, for the insertion of the first pair of legs. The base of
the cephalothorax is narrower than the anterior margin of the
abdomen, and the second pair of legs are inserted in the angles thus
Further Notes on British Oribatide.. By A. D. Michael. 15
formed. The cephalothorax bears a complicated series of ridges
not easy to describe, and which will be best understood by reference
to the drawing. I will, however, endeavour to give an idea of their
arrangement in words. ‘The median (or axial) portion of the
vertex is divided into three spaces bordered by strong raised ridges.
The anterior one is trapeze-shaped, with the small end foremost and
coming near to the point of the rostrum, but not reaching it. Two
short ridges, however, run from the anterior angles of the trapeze,
one to each side of the rostrum, very near to the point. The ridge
which forms the posterior border of the trapeze forms the anterior
border of a hexagon, which has curved sides, convex inwards, the
anterior side being the longest, and the two next sides very short.
The posterior ridge of the hexagon forms the anterior margin of an
oblong or elliptical figure, usually somewhat constricted in the
middle. This figure extends back on to the abdomen, so that it is
difficult to say where the abdomen commences in the median line.
From the central angle on each side of the hexagon a short trans-
verse ridge runs about half-way towards the lateral margin. From
its termination a ridge runs forward to the front of the excavation
for the first leg, and another, or continuation of the same, runs
back toa circular ridge surrounding the stigma, and from the stigma
a triangular space bordered by another ridge extends to the lateral
margin. The stigmatic organs are short, globular, on a short
peduncle, and very white. ‘he interstigmatic hairs are absent or
little seen ; the rostral hairs are present.
The legs are stout and gradually diminished towards the end.
The third and fourth joints of the two front pairs each bear a strong
serrated spine on the upper side; the other hairs on the legs are
short, and the tactile hair is absent.
The abdomen is flat in general effect, but has somewhat raised
anterior and lateral edges, and is raised to about the same extent
along the median portion, being slightly arched there; between
this median portion and the lateral edge is a depressed channel.
The whole abdomen is covered with wavy closely-set irregular
wrinkles. Three or four of these run along the anterior, and about
half-way down the lateral margin; the centre of the space enclosed
by these last-named wrinkles is occupied by a set of wrinkles
bending strongly forward. Behind them the wrinkles become
more transverse, until near the posterior margin, where they again
bend strongly forward. The posterior margin is set with eight
spatulate hairs, of which the two lateral pairs are very short, the
two central pairs much longer and directed inward, the central pair
crossing.
I have only found the species on the lichen near the sea-shore,
at the Land’s End, Cornwall. It has not to my knowledge been
recorded before I found it, and it is not common.
16 Transactions of the Society.
Damzus moniipzs, n.sp. Pl. II. Figs. 1-5.
Average length about 34 mm.
+ breadth 5, “1/8 .,
Bs length of legs, 1st pair, about °17 mm.
A 3) 2nd and 3rd pairs, about ‘15 mm.
a ¥5 4th pair, about *19 mm.
This is an extremely minute but rather elaborately formed
species. I have included it provisionally in the genus Dameus,
_ but that genus will probably require division—perhaps by reviving
Koch’s genus Oppia, and properly defining it, in which case the
present might well serve for a type-species. The colour is rather
light brown, and has a whitish shade over some of the raised parts.
It is not very strongly chitinized, and is indeed rather more leathery
in texture than most of the family, except the genus Nothrus, and,
like many other Orcbatid# which have this texture, and are thus
not as fully protected as harder species, it makes up for the
deficiency by covering itself with dirt to such an extent that it is
almost impossible to get it clean, its very small size being an addi-
tional difficulty. The figure and this description are taken from a
carefully cleaned specimen, otherwise many of the details would not
be seen. Another source of error, which must be avoided in iden-
tifying the species, is that the elevations on the dorsum of the
abdomen are apt to lose their form and be very difficult to see
shortly after death, particularly if treated with reagents. By care,
however, the true form may be preserved.
The division between the cephalothorax and abdomen is very
marked. The actual rostrum is short and conical, not a third of
the length of the dorsum of the cephalothorax. Behind this the
cephalothorax is covered by a tectum or its homologue, but the
whole of it is anchylosed to the surface of the cephalothorax, and
does not stand free. The lateral edges are straight or slightly con-
cave, but very rough. The anterior edge is rather convex; the
wings of the tectum are well marked, and are also anchylosed to
the surface of the cephalothorax; they are reflexed, sloping
downwards on the side of the cephalothorax. A strong ridge runs
along the juncture of each wing with the tectum, and this ridge
projects forward beyond the edge of the tectum, forming a strong,
rough, curved point, terminated by a hair; indeed, it seems to have
taken the place of the projection frequently found at the anterior
edge of the wing. The whole tectum is reticulated, but the reticu-
lations are not easily seen on the wings. Behind the juncture of
the tectum the cephalothorax rises suddenly, and forms a rough
central lump, at the edges of which are the stigmatic tubes pro-
jecting to an unusual degree, the stigmata opening at the extreme
edge of the body. The stigmatic organs (or hairs) are long,
spatulate, rough, and point upward, outward, and backward.
Further Notes on British Oribatide. By A. D. Michael. 17
There is a deep depression between the hinder part of the cephalo-
thorax and the abdomen.
The legs are very remarkable, or at least the first pair is.
They are by no means so long as is usual in the genus Dameus,
and the forms of the pieces are singular. The coxe are not visible
from the dorsal aspect, and the expansion of the cephalothorax
above mentioned has a deep cleft to admit the upward motion of
the thin proximal end of the so-called trochanters of the first pair of
legs. This joint is greatly enlarged. The first two pairs of legs
have the so-called femurs very short, with a short, thin, proximal,
and a much broader, almost square, distal end. The tibize of the
first pair of legs are the pieces which render the legs exceptional ;
they are globes which appear disproportionately large, and are
borne on extremely short and very thin proximal ends. The tarsi
are all pyriform, and thickly clothed with hairs. ‘The enlarged
tibia bears a long tactile hair.
The abdomen is elliptical, slightly pointed posteriorly, and
strongly truncated in front; its antero-lateral angles are produced
into well-marked points, which curve towards the stigmata, so that
from the dorsal aspect two open spaces are seen, bounded on the
outside by these points, and anteriorly by the coxe of the third
pair of legs. Immediately behind the anterior margin there is a
broad, rounded, transverse elevation, not reaching the lateral
margin. Behind this is a deep, linear depression, and then the
centre of the abdomen, until within a quarter of its length from
the hind margin, is occupied by a domed lump, followed by a
smaller one, which touches the hind margin. Exterior to these
elevations the abdomen is a broad, almost flat, expansion, which
seems to form a flat annulus round the central elevation. At the
extreme edge of this is a narrow, rough ridge. The annulus curves
downward towards the margin, but not very strongly. The whole
surface of the abdomen is rough and irregularly sprinkled with
raised dots, which are far largest and most conspicuous on the
central lump.
The Nymph.
This is also rather a complicated creature, not very easy to
describe. The colour is light oak-brown, with a tendency to a
grey dusty effect over the raised parts of the skin. The texture is
a little like fine shagreen, and the general outline is a shield-shaped
abdomen surmounted by a bluntly conical cephalothorax.
The cephalothorax is rather more than one-third of the whole
length; at its base it is nearly as wide as the abdomen. The
rostrum is rounded anteriorly, and slightly truncated. A blunt
point on each side of the truncation carries the curved rostral hair.
The cephalothorax appears arranged in three spaces, which, com-
Ser, 2.—Vot. II. ©
18 Transactions of the Society.
mencing anteriorly, are, first, the rostrum, which bears two longitu-
dinal ridges commencing close to the above-named points, but
sometimes a trifle nearer the lateral margin; the second division
extends from the rostrum to the insertion of the first pair of legs,
and has a central shield-shaped space on the dorsal surface, enclosed
by a raised ridge, against the front of which the ends of the before-
named longitudinal ridges abut. A smaller space, narrower in
proportion, on the slope of each side, is also enclosed by a ridge.
‘The third portion of the cephalothorax extends to the abdomen, and
has a central octagonal space enclosed by a similar ridge, abutting
on the shield-shaped ridge anteriorly, and on the abdomen. pos-
teriorly. On each side of the octagon is a rounded, somewhat
mamillar portion, bearing the stigma, which is dorsal. The stig-
matic organs (or hairs) are long, filiform, rough, and sinuous. The
interstigmatic hairs are apparently absent.
The degs are rather short, of almost even thickness throughout,
rough, and with a projecting point on the front tibiae, which bears
a very strong tactile hair. The other joints each have a pair of
short, curved, spatulate hairs. ‘The tarsi are short and thick, and
clothed with numerous fine hairs.
The abdomen carries the cast notogastral skins stretched quite
flat on the back, except that the edges of each skin have curled up
and form ridges, thus, in the full-grown nymph there are three
almost concentric ridges. Within the space enclosed by the inner
ridge—i.e. upon the larval skin—are three hemispherical knobs,
arranged longitudinally. ‘There are two projecting points at the
posterior end of the creature, and of each cast skin, and each point
bears a long, spatulate, curved hair.
The creature lives in decayed wood. I first found it in some
material brought from Yorkshire by the Rey. H. Tattershall,
and I have since found it myself in Hopwas Wood, near
Tamworth.
ee, -o-
( 19 )
IL—A New Growing or Circulation Slide.
By T. Caarters Wuirz, M.R.C.S., F.R.M.S.
(Read 14th December, 1881.)
TcrEastnG attention has of late years been devoted to the subject
of slides by which the development of microscopical organisms can
be observed, but the majority of the forms suggested have been
attended by various drawbacks and disadvantages in their design
and construction, leading to their disuse. The one here described
seems to be as efficient as can be desired; it is, however, merely
put forward as a suggestion, and I do not venture to claim for it
more than simplicity and efficacy to recommend it to microscopical
observers.
It often happens that in examining a gathering from some
aquatic source an organism is met with about which the observer
would desire to know more, but to transfer it from his slide to
one of the growing slides in ordinary use would probably result in
its loss or destruction. The slide now described is designed to
supersede the use of the glass slip generally used for this examina-
tion, so that should such an organism present itself all that is
required to maintain a constant current is the insertion of threads
of cotton into openings in the sides of the cell. The organism is
then duly nourished, and no alteration occurs to interfere with ~
ie proper development, which can be readily noted from time to
ime.
The slide (Fig. 1) consists of the usual glass slip AA
(3 in. x 1in.), having a narrow ledge of glass B (about } inch
iniees, Il.
wide, and extending nearly its whole length), cemented to its
lower border with marine glue; to this is cemented at right angles
a strip of thin covering glass C, about + inch wide and about
13 inch from the end of the slide, having a narrow channel cut
through it for the passage of an intake thread D. A similar strip
0 2.
20 Transactions of the Society.
B, having a like cut through it for the passage of an outlet thread
F, is cemented at the same distance from the opposite end of the
slide. In this condition the slide being filled with water to the level
of G, any current coming in through the intake thread D would
pass directly across the top of the water in the cell, and pass out
by the outlet thread F, and organisms near the bottom of the cell
would not be benefited by a change of water; I therefore cement
a very narrow slip H of the same covering glass as before to the
inner side of the outlet end of the cell, commencing at the top of
the slide, and extending to very nearly the bottom, so as to leave
about ;!, inch between E and H. If the intake thread is connected
with a bottle of water placed above the level of the slide, water
entering by the intake thread will pass in a diagonal direction
from D to the left and bottom of the cell, where the influence of
the suction set up by the siphon-like action of the outlet thread
makes itself felt, and there is a regular current in the direction
of the arrows.
The front of the cell is formed of a piece of thin covering glass
of 1}inch by §,and two small square blocks of glass I, cemented on
each side, will hold this covering glass sufficiently firm to prevent
it sliding on the organism and crushing it.
Such a growing slide will hold about 1 drachm of water, and
taking the rate of the drops from the outlet thread as about one
per minute, the whole of the water in the cell is changed once in
an hour, while at the same time the current is not sufficiently
strong to carry away more than the finest and lightest bodies.- It
allows of fair observation with a -inch objective, and if desired
could be made with thinner glass, so that a 2-inch or g-inch might
be used.
ee
( 21 )
IIl.—On a Hot or Cold Stage for the Microscope.
By W. H. Symons, F.R.MS., F.CS.
(Read 14th December, 1881.)
Tuis stage consists essentially of a copper or brass box A, Fig. 2,
8 cm. long, 5 cm. broad, and 1°5 cm. deep; an open tube F,
5 x 2 em., communicates with the interior, and allows of the
expansion of the contents and for filling. In the upper and lower
sides of the box are apertures H, for the passage of light, 2 em.
in diameter, the lower covered by a thin glass cover, 2:5 cm. in
diameter, and the upper by one which constitutes the working
stage, 3°5 cm. in diameter. Both covers are kept in position
Hig. 2:
E £ ——
ie SS is
(Sy, 2S ee paar ie Tigo és
| SF bi _y fF — EW TRANEE TOR COOTER?
ao * =e
ee e|| ENTRANCE FOR HEATER
between pairs of vulcanized rubber rings by means of brass plates
D, clamped on with screws H, the plates being furnished with
apertures slightly smaller than the thin covers. A thin copper
ipe BB, 5 mm. in diameter, is carried round the bottom of the
inside of the box A, one end being forked, and all three branches
furnished with taps. ‘This pipe serves to convey the heating or
cooling agent to the water or other liquid contained in the box.
The temperature is ascertained by means of a thermometer C,
having its bulb bent in a circle slightly smaller than the aperture
for light; it is placed in the box with the bulb almost touching the
upper thin glass cover. Between the thermometer and the copper
pipe is a copper partition, having a number of slots in its base to
allow of the circulation of the water. In this way the thermometer
is protected from undue heat, and as all water which reaches the
upper thin glass must pass it, a very near approximation to the
temperature of the object upon the thin glass is obtained, espe-
cially if the object is protected from currents of air by a cardboard
shade.
The most convenient heating agent is steam, a small flask
100 c.c. capacity will work for over an hour, and the temperature
may be varied from normal to 95° C. at pleasure; steam, however,
gives out its latent heat immediately on coming in contact with
the tube, and therefore that portion of the box or bath nearest to
the supply becomes warm very much sooner than that further
22 Transactions of the Society.
from it; if great exactness be required steam can be replaced by a
current of warm water or saturated solution of chloride of calcium,
which give out only specific heat, and that nearly equally through
the whole length of the tube. In either case the box is filled with
recently boiled distilled water or a saline solution, and placed, with
a non-conductor intervening, upon the stage of the Microscope, so
that the optic axis corresponds with the centres of the apertures ;
one of the forked tubes is then connected with the hot fluid, the
other with a supply of ice-cold water, and the exit end of the
copper tube with an empty vessel. The object is now placed upon
the thin glass stage, covered with another thin glass, and sur-
rounded with a cardboard shade and focussed. The heating agent
is circulated through the copper pipe until the required tempera-
ture is attained, the tap can be then turned off, and if a sudden
reduction of temperature be necessary the tap which communicates
with the cold water turned on.
Ifa temperature above the boiling-point of water be required,
the box is filled with glycerine, and the heat from a gpirit-lamp
conveyed to it by means of a projecting copper plate, one end
being in contact with the bottom of the box, the other in the flame
of the lamp. In this way any ordinary temperature can be
obtained, but it is not so completely under control as the steam,
there being a rise of some 10° after removing the source of heat.
If a very low temperature is wanted, all the metalwork is
covered with felt, and the box filled with clean crystals of ice and
salt and water.
This stage is specially adapted for those cases where a rising
or falling temperature is required. It was originally contrived
for studying the tumefaction of starches, noticing the temperature
at which the various granules burst, but I have found it useful
also for ascertaining roughly the melting-points of fats, by
observing when the crystals in them disappear; and for jellies,
resins, and other structureless, easily fusible, substances, by noticing
when small particles assume the liquid form; and it will obviously
have many other applications.
Peketir rica, triks
( 23 )
SUMMARY
OF CURRENT RESEARCHES RELATING TO
ZOOLOGY AND BOTANY
(principally Invertebrata and Cryptogamia),
MICROSCOPY, &c.,
INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.*
ZOOLOGY.
A. GENERAL, including Embryology and Histology
of the Vertebrata.
Photographs of the Developmental Process in Birds.j —C.
Kupffer and B. Benecke give fifteen photographic plates of the
embryos of birds, with full descriptions, the outlines of the photo-
graphs being drawn on transparent paper, on which the necessary
lettering is placed. A full description of the photographic apparatus
is given, and it is stated that osmic acid was found to give to the embryos
a colour suitable for photographic reproduction. When whole embryos
are reproduced, the amplification is ten, and when one or other end
only is photographed, it is twenty times. Some of the photographs are
particularly good, and the tracings form admirable diagrammatic
representations of the different relations of the parts. An important
fact to which attention is drawn is, that within the limits of one
species variations have been found to be much more marked in the
earlier than in the later periods.
Development of the Paired Fins of Elasmobranchs.t — Mr. F.
M. Balfour states that in Scyllium these arise as slight longitudinal
ridge like thickenings of the epiblast, and that in Torpedo the ante-
rior and posterior are on either side transitorily connected together
by a line of columnar epiblast cells. Later on, the fins become a
ridge of mesoblast covered by epiblast ; the embryonic muscle-plates
grow into the bases of the fins,and form two layers, while in the
intermediate indifferent mesoblast changes begin to be set up, which
give rise to the cartilaginous skeleton. There is thus formed in the
fin a bar which springs at right angles from the posterior side of the
* The Society are not to be considered responsible for the views of the
authors of the papers referred to, nor for the manner in which those views
may be expressed, the main object of this part of the Journal being to present a
summary of the papers as actually published, so as to provide the Fellows with
a guide to the additions made from time to time to the Library. Objections and
corrections should therefore, for the most part, be addressed to the authors.
(The Society are not intended to be denoted by the editorial ‘‘ we.”)
+ Nova Acta Acad. Czes, Leop.-Carol. Germ, Nat. Cur., xli. i. (1879) pp. 149-96
(1 pl. and 15 photos.).
} Proc. Zool. Soc. Lond., 1881, pp. 656-71 (2 pls.).
24 SUMMARY OF CURRENT RESEARCHES RELATING TO
pectoral or pelvic girdle, and runs parallel to the long axis of the
body. The free end of the bar begins to undergo segmentation into
rays, and much of this is effected “before the tissue of which the
plates are formed is sufficiently differentiated to be called cartilage by
an histologist.”
We have then a longitudinal bar along the base of the fin, which
gives off perpendicularly a series of rays which pass into the fin. It
is pointed out that, from its position this basal piece can never have
been a median axial bar with rays on both sides. The resemblance
to the arrangement of the unpaired fins is consequently very striking,
and support is given to the author’s original doctrine of a once
continuous lateral fin.
Development of the Sturgeon.*—In continuation of his previous
paper, Professor W. Salensky points out that in this fish it is very
difficult to fix the limits between the period of the formation of the
embryonic layers and that in which there appear the earliest rudi-
ments of the organs. Here we find that the envelopment of the
inferior by the superior portion, and the further differentiation of the
embryonic layers is contemporaneous with the appearance of some of
the organs in the mesoblast. Dealing with the modifications under-
gone by the egg up to the point at which the medullary groove
becomes closed, the author states that organs begin to appear at the
termination of the first day of development. On the second day a
groove 0:7’ in length appears in the middle of the embryonic area.
The posterior extremity of this groove corresponds exactly to the
blastopore. In the next stage the anterior end of this primitive
groove dilates to form the rhomboidal rudiment of the brain. The
hinder part of the groove opens directly into the primitive digestive
cavity by means of the blastopore, and it is only near the end of the
period of development that the union between the digestive and
medullary cavities ceases to exist. Meantime, the lateral parts of the
embryonic area have been undergoing important changes. On either
side there appears a white band which behind diverges slightly
from its fellow. These are the first indications of the Wolffian ducts ;
and the parts internal to them become modified to form the vertebral
plates, and those external to them the lateral plates.
Previous, however, to the appearance of the groove on the surface
of the embryonic area, important changes have been taking place
within. There has appeared an axial thickening, formed from the
ectoderm and mesoderm, which has an intimate connection with the
formation of the notochord and of the central nervous system. These
changes are described in detail. The mesoderm becomes divided into
a median and lateral portions; the first constitutes the notochord,
while the side pieces give rise to various organs. After the appear-
ance of the medullary groove we may distinguish a central portion in
which the groove is placed, and lateral parts which are distinguished
by having over them the enveloping lamella. The bases of the cells
which form the floor of the groove are strongly pigmented, and this
* Arch. de Biol., ii. (1881) pp. 279-341 (4 pls.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 25
pigment is derived from the ectodermal cells which become confounded
with the cells of the medullary plates.
The further development of the nervous system consists in the
progressive development of the lateral pieces which correspond to the
medullary plates of other Vertebrates. Atabout this stage the parts of
the mesoderm give rise to the excretory organs.
After the medullary groove becomes closed it is possible to dis-
tinguish a cephalic from a trunk region, and the boundary between
the two corresponds to the anterior ends of the Wolffian bodies.
Owing to the transparency of the embryonic area it is possible to see
that the trunk grows by a gradual increase in the number of the
primitive segments. Having before had five somites, we see these
last increase as changes go on in the form and position of the blasto-
pore. While the anterior segments retain their perpendicular position,
the posterior become inclined to the longitudinal axis, to return later
on to their primitive position. While elongation is proceeding, the
trunk becomes thicker, the dorsal region increases in size, and there
is exhibited a slight inclination to the right, the appearance of which
causes a certain asymmetry in sections taken at this period.
Soon the blastopore closes, and its position is marked by an accu-
mulation of pigment. The rudiment of the tail becomes visible by
the formation of a tubercle; the cephalic extremity possesses two
vesicles, and the mesoderm is still thin anteriorly. Where the
cephalic plate enlarges, a central and a peripheral part may be distin-
guished, the branchial clefts begin to appear, and a facial process is
developed in front of the head. The heart does not commence to con-
tract till the end of the period of embryonic development, and its
contractions are at first very slow. Simultaneously with this the
veins and their ramifications appear.
The author next proceeds to a study of the development of the
internal organs with which he considers the modifications of the
embryonic layers. He points out that the ectoderm consists of two
layers, of which the superior is, at first, strongly pigmented ; through-
out its development its cells nearly all retain their original flattened
character ; the lower layer is that which contributes most largely to
the formation of the sensory organs in which, except in the case of the
olfactory fosse, the outer layer takes no part. After describing the
details of the development of the central nervous system, Professor
Salensky raises the question of the homology of this region with
the nervous system of Vermes and Arthropoda. He points out that
(1) the central nervous system of all Vertebrates is formed from
two thickenings of the ectoderm, set parallel to the long axis of the
body: that of all Articulates has a similar origin. (2) In some cases,
e.g. Echiurus, the “ Articulates” present a median groove comparable
to that of Vertebrates. (8) The formation of the medullary groove
commences, in the case of both phyla, posteriorly, and is continued
forwards. On the other hand the Vertebrata have the central neryous
system dorsal in position, and the medullary groove becomes closed.
As to the first of these, he points out that the position of the mouth
is the determining character, in conjunction with that of the loco-
26 SUMMARY OF CURRENT RESEARCHES RELATING TO
motor organs; these points he looks upon as having less morpho-
logical value than the development of the system, and its correlation
with other organs during the course of development. The closure
of the medullary groove is regarded as being merely the result of
further modifications.
If we accept the general homology, we have next to determine
how the parts correspond; the author cannot follow Dohrn and
Hatschek in regarding the homology as being complete; he looks
upon the brain of Vertebrates as being a new formation, which is
their exclusive property; it merely consists in an elongation and
dilatation of the already existing nervous system, or in other words
the medulla, which is the analogue of the ventral ganglionic chain of
the Articulata. ;
The mesodermal derivates are dealt with in great detail, and a
comparison with what is seen in Plagiostomi leads the author to say
that they approach the higher, while the Ganoids approach the lower
Vertebrata ; and this portion of the essay concludes with an account
of the development of the enteric tract.
Development of Petromyzon Planeri.* — J. P. Nuel directs
attention to the phenomena of the contractility of the ovum: imme-
diately after impregnation, before which the vitellus was everywhere
closely applied to the chorion, the yolk commences to contract, till
at last it is at all points separated from its investment. Calberla
regarded this as being due merely to osmotic action, but the fact
seems te be that a contractile wave, starting from the active pole,
slowly but gradually passes over the whole of the yolk; this takes
about twelve minutes to be effected.
From the moment when the egg begins to segment there is
a period of rest between each division, and this period shortens
as development advances; when the segmentation period is at
an end the cells of the hypoblast are in repose for a lengthened
period, while the epiblastic cells, continuing to divide, give rise to
an epibolic invagination. At a certain period most of the hypoblastie
cells start into activity, and the elements of the digestive tract begin
to be formed ; some of them, however, still remain quiet, and, only
later, give rise to the liver. When a group of cells enter into
activity, their calibre diminishes, and the yolk-grains are fused
together.
After describing the details of the development of the digestive
tract, M. Nuel states that the transformation of the yolk-spheres
first takes place along the axis of the embryo; commencing at the
anus of Rusconi, it rapidly extends forward; being most intense at
the point where the epiboly is most advanced; thence it widens out,
and gradually invades the whole surface of the hypoblast, till it
comes into contact with the segmentation cavity.
When the mesoblast developes, it is clear that it has no relation
to the chorda dorsalis ; for the two are simultaneously differentiated
from a common embryonic layer, which, later on, also gives rise to
* Arch, de Biol., ii. (1881) pp. 403-54 (2 pla.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 27
the secondary hypoblast; the mesoblast in Petromyzon, just as in the
Sturgeon (Salensky) is developed from behind forwards.
The chapter on the germinal layer is largely occupied with a
criticism of the observations of W. B. Scott; and the author con-
cludes by giving his adhesion to the doctrine of His, that the study
of the mechanical causes which affect the embryo, and the causal
connection of the changes which take place in the egg are the true
objects of embryology, and he points out that this side of the study
is to descriptive embryology what physiology is to zoology.
White Corpuscles of the Blood.*—M. Renaut describes the
different forms presented by the white corpuscles in different animals.
In the Crayfish, besides the ordinary lymph-corpuscles, there are
many larger bodies with well-defined nuclei, the protoplasm of which
contains large highly refracting granules, resembling in many
respects the vitelline granules of the Frog and other Batrachia. These
corpuscles have a sharply limited, but thin exoplastic pellicle; and if
a drop of such lymph be allowed to fall into a drop of a 1 per cent.
solution of osmic acid, the white corpuscles are instantly fixed, with
their pseudopodia or protoplasmic processes extended; and these
processes can then be seen to perforate the thin membrane, now black-
ened with the acid. There are thus two kinds of white corpuscles in
the Decapod Crustacea—the lymphoid corpuscles and the amceboid
corpuscles.
Do similar differences exist in the blood of Vertebrata ?
In reply to this, M. Renaut states that in the blood of all the
Vertebrata, from the Cyclostome to the Saurians, the white corpuscles
are of two kinds; one, the ordinary white corpuscle, composed of
hyaline protoplasm, presenting many short projecting points, with a
nucleus undergoing gemmation, and sending forth branched pseudo-
podia when placed under favourable conditions; the other containing
numerous brilliant granules imbedded in the protoplasm and sur-
rounding the nucleus. These resemble the second form of corpuscle
described above as existing in the lymph of the Crayfish, but differ
from them in having no outer limiting layer of condensed protoplasm,
or exoplasm, as Haeckel has named it. The application of osmic acid
shows that they may be subdivided into two other forms, one closely
analogous to cells undergoing transformation into fat-cells, which
present numerous granules, and stain black with osmic acid, and
another set which contains granules that are not fatty, but which
stain red with eosin. The best mode of demonstrating the existence of
these three forms is to fix the blood in the rete mirabile of the capil-
lary layer of the choroid in the posterior segment of the eye of a frog,
by removing the anterior segment and exposing it to the vapour of
osmic acid. At the expiration of twelve hours the eye is removed
from the vapour, washed, the chorio-capillaris detached from the
retina, and spread on glass; it is afterwards coloured with, and
mounted in, hematoxylate of eosin. The corpuscles may then be
studied, and the three forms of ordinary, granular, and fatty corpuscles
can be easily distinguished.
* ¢Science,’ i, (1881) p. 505, from ‘ Arch. de Physiol.’ and ‘ Lancet.’
i
28 SUMMARY OF CURRENT RESEARCHES RELATING TO
M. Renaut finds that the white corpuscles of mammals generally,
and of man in a state of health, all closely resemble each other, and
are of the ordinary kind; but in disease, as in leucocythemia, the
white corpuscles are not only greatly increased in number, but vary
considerably in size. Moreover, they are round, and present no
pseudopodia. They are hyaline, and have a smooth, well-defined
limiting membrane, and some of them have nuclei which have under-
gone fission, just as in a cell that is about to segment. Hence, he is
of the opinion that the white corpuscles multiply and increase in
number while floating in the blood; other corpuscles may be
observed, which are charged with granules of some proteid substance,
resembling vitelline granules, or small masses of hemoglobin ; and,
lastly, there are still other cells, which are charged with fat. M.
Renaut has made some observations on the development of the
red corpuscles of the Lamprey, and gives the following succession of
forms. White corpuscle with nucleus proliferating and protoplasm
not limited by an exoplasmic layer; corpuscle with nucleus prolifer-
ating, the protoplasm forming an uncoloured disk, limited by an
exoplasm ; corpuscle with proliferating nucleus, protoplasm limited
by an exoplasm, and forming a disk, more or less charged with
hemoglobin; red corpuscle with proliferating nucleus; and finally,
circular red corpuscle, with rounded nucleus.
Nerve-endings of Tactile Corpuscles.*—W. Krause discusses the
different views which have been held as to the condition of these
nerve-endings, viz.:—(1) Langerhaus, who considers that the fibres
divide di- or trichotomously after entering the corpuscle, and end
thus by only two or three terminal twigs which may be flattened
into terminal disks, as is generally the case in the end-bulbs, and
especially in the round ones. (2) Ranvier, who states of the laminar
terminal corpuscles of the tongue of water-birds, &c., and of the
laminar tactile corpuscles, that a terminal disk is interpolated
between every two of the cells which lie transversely in the bulbs.
Krause obtained similar results by the use of formic acid and chloride
of gold. (35) Meissner, from pathological and other observations, has
set down all the transverse striation to nervous structures, except
some possibly due to nuclei. But Krause, supported by Fischer and
Flemming, has explained the large number of transverse nervous
terminal fibres as due to a spiral course of the latter, accompanied by
repeated dichotomous branching.
In order to reconcile the three views, it may be held that
Langerhaus’ opinion applies to some of the smallest and simplest
corpuscles; while Ranvier’s apply to their larger and more usual
forms; whereas Fischer’s preparations show the course taken by
the terminal fibres in reaching their disks. Krause himself holds
the inner bulbs to consist of transverse bulb-cells with pale terminal
nerve-fibres ending in knobbed or discoid terminations between
them.
* Arch. mikr. Anat., xx. (1881) p. 215 (1 pl.); and Biolog. Centralblatt, i.
(1881) pp. 462-3.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 29
Distribution and Termination of Nerves in the Cornea. * —
Opinions have differed widely as to the actual mode of termination of
the corneal nerves, whether singly or by fasciculi in the corneal cells,
or by reticulations surrounding them. These and kindred questions
have been investigated by Professor G. V. Ciaccio. He has studied
animals from all the Vertebrate classes except fishes, and has chiefly
employed chloride of gold to render the nervous elements visible. His
results are summed up as follows :—
1. The nerves of the cornea are of different kinds and have
different functions, viz. (a) sensitive, some to light and some not, and
(b) trophic, regulating the nutrition of the tissue.
2. They form a plexus, the “ circumferential nervous plexus”, at
the circumference of the cornea before entering it; this consists
partly of medullated, partly of non-medullated fibres.
3, This plexus sends out branches and twigs of different sizes in
various quantities, which enter the cornea, divide and subdivide there
and form a plexus, the “ primary or principal nervous plexus,” which
traverses its entire breadth; in the rabbit, mouse, rat, and bat it lies
chiefly near the anterior face ; in lizards, tortoises, frogs, and tritons
it is near the middle of its thickness ; in birds it is mostly contained
in its anterior portion.
4, Other plexuses exist in this organ, more or less derived from or
dependent on this chief one; they are termed secondary or accessory ;
they sometimes lie above, sometimes below the chief one. In the
frog this plexus lies below the latter, and close to Descemet’s mem-
brane; in the mouse, it lies above, close to the anterior face of the
cornea and thus constitutes the “subbasal plexus” of Hoyer and
others.
5. The principal plexus gives off a large number of small branches,
sometimes accompanied by ultimate fibres; they are termed “ per-
forating branches”; they break up first below the epithelium, each
into a tuft of fibrils, which form between themselves the “ subepi-
thelial plexus,” of greater or less closeness, and differently arranged
in different animals. In the mouse and rat, and perhaps the bat, it
has a concentric arrangement, but the centre does not correspond to
that of the cornea.
6. From different places in the subepithelial plexus fibrils go off
and enter the epithelium, dividing and anastomosing, and thus forming
in it a very delicate reticulation, probably broken off here and there,
(the intra-epithelial rete or plexus of modern authors); the fibres
terminate either in small button-lke dilatations or simply below
the outermost cells of the epithelium, which form a delicate mem-
brane interposed between these endings and the exterior.
7. The various plexuses and networks thus formed are not to be
considered as so many distinct units but as so many compound systems,
each of them being made up of as many parts as there are nerves
entering into its constitution. Thus, by their distribution over the
cornea, the nerves form just so many anatomically and physio-
logically distinct regions as there are trunks and branches of nerves,
* Mem. Accad. Sci. Ist. Bologna, ii. (1881) 24 pp. (2 pls.)—Sep. repr.
30 SUMMARY OF CURRENT RESEARCHES RELATING TO
8. The nervous fibres, both those of the proper substance of the
cornea and those of its epithelium, always terminate in two ways,
namely, by plexus or reticulation and by free ending. The latter
mode, when occurring within the cornea, takes place not only in the
branching cells but also within or between the fibrous lamin.
9. The axis-cylinders of the corneal nerves are made up, like the
fibres of striated muscle, of fibrils, each of which consists of minute
particles and of a peculiar intermediate substance which unites them
in linear series; in this case these particles are round, whereas in
muscle they are prismatic.
Influence of Food on Sex.*—The results of experiments detailed
by E. Yung tend to confirm those previously obtained by G. Born,
who found that when young tadpoles were subjected to special kinds
of food (in one case vegetable food being given, in another mixed
vegetable and animal), a large preponderance of females were deve-
loped. In these experiments there was an absence of what forms the
chief normal food of tadpoles, viz—marsh-slime, containing various
organic detritus, rotifers, infusoria, diatoms, &c.
Yung reared the tadpoles of Rana esculenta in four vessels, feed-
ing the broods respectively on fish, meat, coagulated egg-albumen,
and egg-yolk. The percentage of females in each case was 70, 75,
70,and 71. Ina fifth vessel, out of a brood of 38 tadpoles nourished
simultaneously on meat, algze, and white of egg (without slime), 30
were females, six males, and two doubtful. These results seem to
demonstrate that the quality of the food experimented with exercised
no distinct influence on the sex, but that a special diet given to young
tadpoles from the time of hatching favours the development of a
female genital gland, as Born concluded.
B. INVERTEBRATA.
Mollusca.
Digestion of Amyloids in Cephalopoda.t—E. Bourquelot in
attempting to resolve the contradictory statements that have been
made with regard to the presence of a diastatic ferment in the liver of
the Cephalopoda, finds that the quantity of starch which is altered
varies with the condition of the individual. When it is starving the
action is slow and difficult to detect, for the gland is then in repose; but
when digestion is going on in the animal the change is almost instan-
taneous. As in mammals, ruptured starch-grains are alone acted on.
It is somewhat curious, the author thinks, to find this ferment in car-
nivorous animals, but its presence affects the discovery of the possible
glycogenic function of the Cephalopod’s liyer. Can glycogen and
starch-ferments exist in the same gland? as yet there is no proof of
the presence of sugar in livers that have been properly treated, but, as
_the author justly remarks, in physiological chemistry an experiment
yielding negative results should be frequently and carefully repeated.
* Comptes Rendus, xciii. (1881) pp. 854-6.
+ See this Journal, i. (1881) p. 874.
t Comptes Rendus, xciii. (1881) pp. 979-80.
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. ok
Proneomenia sluiteri.*—Dr. A. A. W. Hubrecht gives a full
anatomical account of this interesting archaic Mollusc, the discovery
of which we have already noted.t There are no external appendages ;
the groove enclosing the foot is indicated by a dark longitudinal
line, the mouth and anus are at either extremity. The integument
is stiff owing to the presence of several layers of spicules of
carbonate of lime; externally to the circular layer there is a cellular
one, which appears to be the matrix of the integument; and
there is an interspicular substance which is homogeneous and
structureless, and appears to be of a chitinous nature. The youngest
spicules are found quite close to the deep cellular layer of the
matrix; the older ones are in communication with this layer
by radiating cords of connective tissue, and the points of the inner-
most project towards the exterior. So far there are certain im-
portant differences between this form and Neomenia, and, in the
latter, blood-vessels find their way into the skin; moreover, in
Proneomenia at the hinder end of the body there are two symmetri-
cally developed czeca connected with the anal cavity, and containing a
special secretion; they are provided with a strong muscular invest-
ment, so that, whatever their homology or functions may be, there
can be no doubt that at times their contents may be forcibly
expelled.
In his account of the muscular system the author states that
in Proneomenia, as in Neomenia, the stronger muscular fibres are
enclosed in a delicate sheath of connective tissue, which forms trans-
verse folds and so gives to the muscle the appearance of being
striated. The most anterior portion of the ventral groove leads
into a system of ciliated slits and cavities which ramify and com-
municate with one another; the whole would seem to form a gland—
the “anterior foot-gland.” The posterior foot-gland has no ciliated
cavities.
The nervous system truly belongs to the type of the Amphineura ;
the single cephalic ganglion is comparatively very small; it gives off
three separate pairs of principal trunks, the innermost of which forms,
asin Chiton, a sublingual commissure ; the second pair surrounds the
pharynx and developes the anterior pedal ganglia; the third pair
gives rise to the longitudinal lateral nerves, and “a regular series
of commissures similar to those between the two pedal nerves,
connect the two lateral with the two pedal nerves.’ The study of
the details of the nervous system reminds Dr. Hubrecht that all late
investigations into the lower Invertebrates appear to point towards
an increased complication of the commissural connections, culminating
in the direct continuity of nervous tissue throughout more or less
extensive regions of the body. It is remarkable further, that “the
lower we descend in the Molluscan subdivision the more a system of
transverse commissures between the longitudinal connective stems
fixes our attention.” Perhaps, indeed, the earlier Mollusca had their
nervous system plexiform in arrangement. Further, the fact is of
* Niederl. Arch. f. Zool., Suppl. Band I., ii, (1881) 75 pp. (4 pls.).
t See this Journal, i. (1881) p. 28.
32 SUMMARY OF OURRENT RESEARCHES RELATING TO
importance that the primary nerves are accompanied by a layer of
nerve-cells.*
The digestive system is divisible into a muscular buccal mass, a
ciliated intestine and the rectum; the pharynx possesses a number of
radial folds, and there is an inner coating of a yellowish chitinous
cuticle. No trace of a radula is to be seen in Neomenia, but in Proneo-
menia it is interesting to observe a muscular process representing the
tongue and invested in chitin; salivary glands appear to be present.
The intestine is uniform throughout, with thin walls, provided
anteriorly with a cecum; the lumen is obstructed by the deep trans-
verse folds, found in this form and its allies, and there are indica-
tions of an incompletely differentiated liver, in the form of secreting
cells on the lateral portions of these lamine.
The generative system is perfectly symmetrical, and consists of the
germ-gland, which is situated along the whole length of the body,
and is dorsal, and of the different cavities and canals found at the
hinder end of the body. The general type in the Solenogastres
appears to be the possession of a double genital gland which com-
municates with the pericardium ; from this a complex of ciliated and
glandular ducts leads towards the exterior, to which it opens in the
region of the anus. The author thinks it possible that part of the
conducting tubes of the genital system represent the kidney. If this
view is supported, we shall find in Neomenia a form in which
the genital products are discharged by a pair of ducts into the
body-cavity (pericardium); thence they are conducted by paired
ciliated ducts into the cavity of the kidney; in other words, we
have indications of a more primitive stage in which the cavity of the
pericardium was the meeting-point of the efferent ducts of the genital
glands, and the excretory ducts of the renal organ.
The circulatory system is almost completely lacunar, the heart is
more or less saccular in form, and as radiating fibres traverse its —
cavity, it has a resemblance to the embryonic heart of some higher
Gastropods: it is possibie that the blood-corpuscles contain hemo-
globin. There appear to be no branchie at the posterior extremity
of the body. The paper concludes with a detailed comparison of this
form with Neomenia and Chetoderma; and of the Solenogastres
generally with the other division of the Amphineura—the Polypla-
cophora.
Molluscoida.
Development of Salpa.t— Professor W. Salensky has a preliminary
communication on this subject, to which his attention has been
compelled by the different results obtained by Brooks and Todaro,
as compared with those of his own earlier investigations. He now
finds that there are great differences between the S. democratica which
he previously examined, and the S. pinnata, which was the subject of
Todaro’s studies. In all species of Salpa the ovary is found at the
hinder end of the body, and consists of an egg-cell, enclosed in a
* We may observe that Balfour has noted a number of commissures between
the ganglia, and a ventral ganglionic layer in the ventral cords of Peripatus.
t Zool, Anzeig., iv. (1881) pp. 597-603, 613-19.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. oa
follicular capsule ; this follicle has a solid stalk, which leads into the
oviduct; where the wall of the respiratory cavity is connected with
this, it is thickened, and the projection so formed was taken by
Todaro for the uterus; the maturation of the ovum is always
accompanied by the shortening of the stalk, till the follicular cavity
becomes connected with the oviduct. After this impregnation takes
lace.
* In further development differences obtain between’ the species as
to the form of the embryo, of its coverings, and of the number of
follicular cells. Considerable differences are seen early between
S. democratica and S. bicaudata ; the former has no amniotic fold, the
latter lies in a prolongation of the body, formed from the cellulose-
mantle, blood sinuses, and a tubular continuation of the wall of the
respiratory cavity. The first signs of the differentiation of the
- central mass is the separation of the lower wall of the follicle, and a
cavity is thus formed which the author proposes to call the follicular
cavity, instead of applying Todaro’s unsuitable term of cleavage-
cavity; this wall becomes the upper wall of the placenta. In
S. pinnata the nervous system arises in the form of a tube with an
at first narrow lumen. In the other species the ganglion has the
form of an aggregate of cells, derived from the follicular cells.
From the connecting canal between the enteric and neural cavities
we have formed a ciliated pit. An account is given of the
formation of a special organ known as the subpericardial aggregate
of cells; Uljanin has informed the author that a similar structure is
to be observed in Doliolum. The eleoblast is formed from the
amceboid follicular cells which give rise to the blood-corpuscles and
muscles.
The author insists on the great differences between the develop-
mental history of Salpe and that of other animals, the organs being
formed not from the cleavage, but from the follicular cells; some-
thing similar has, however, been noted in the allied Pyrosoma; and,
instead of speaking of development of Salpe, he would prefer to give
the process the name of follicular gemmation.
Tunicata of the ‘Challenger.’ *—JIn a fourth communication
Dr. W. A. Herdmann deals with the Molgulidew, and describes
Molgula pedunculata, horrida, forbest, and pyriformis, Hugyra kergue-
lenensis ; Ascopera is a new genus with a pyriform, more or less
pedunculated body, the test thin, while the branchial sac has seven
folds on either side: A. gigantea and A. pedunculata.
Arthropoda.
a, Insecta.
Striated Muscle of Coleoptera and its Nerve-endings,|—The
main results obtained by Professor L. v. Thanhoffer on this subject
show the striated muscle of Coleoptera to possess two separate sarco-
lemmar membranes, between which the nerye-ending plate spreads
* Proc. Roy. Soc. Edinb., 1881, pp. 233-40.
+ Biolog. Centralblatt, i. (1881) pp. 349-51.
Ser. 2.—Vot. II. D
34 SUMMARY OF CURRENT RESEARCHES RELATING TO
out, the axis-cylinder of the nerve dividing dichotomously, and the
nerye forming a reticulum in the plate. In the Frog no such
reticulation is formed, but the divisions of the axis-cylinder come
into contact with the nuclei which overlie the muscle-fibre. In the
beetle the nerve-substance of the plate is separated from the muscular
substance by a membranous structure which is connected with
Krause’s transverse lines. Strong contraction, produced by electricity,
causes resolution of the transverse lines of the muscle into molecules ;
but fine strie, due to the approximation of Krause’s lines, are still to
be seen, except after very violent contraction, All the described
forms of cross lines can be seen in the Coleopteran muscle. The
outer sarcolemmar sheath is in connection with the outer sheath of
the tendon; areticular lymphatic canal-system ramifies from the latter
and terminates in the uniting substance of the fibrils, showing cell-
like granular structures at the points of division.
These canals show connective-tissue cells bearing processes shaped
like windmill-sails at the point of insertion of the tendon. The main
nerves of the muscles lie in special “ perineural ” cavities, lined with
amultilaminar sheath. Isolated muscular fibres of Hydrophilus piceus,
connected with end-plates, show the Krause’s lines next to the mem-
braneous neural septum to be in close apposition, whereas towards
the sides they become gradually more distant ; they appear to converge
towards the plate when near it, but to diverge when remote from it.
Terminations of the Motor Nerves in the Striated Muscles of
Insects.*—H. Viallanes has studied the mode of termination of the
nerves in the muscles of the larve of Stratiomys chameleon Macq. and
Tipula gigantea Macq., and finds that in both the muscular fibre is on
the same plan as that of Vertebrata ; and consequently differs greatly
from that of adult insects, which is histologically distinct. The
results which he obtained cannot therefore be compared with those
obtained by most of his precursors, who studied chiefly adult insects.
In Tipula each muscular fibre receives only a single nerve, and
has only one Doyére cone: but in Stratiomys each receives several
nerves, and has several Doyére cones.
The sheath of the nerve continuous with the sarcolemma constitutes
the wall of the Doyére cone.
The axis-cylinder haying penetrated to the summit of the cone
divides into two principal branches, which give off secondary branches;
these again divide dichotomously a great number of times. There
results a terminal nervous plexus beneath the sarcolemma, and com-
parable to that in the Vertebrata. The author claims to have been
the first to point out such a plexus in other animals than Vertebrata.
This plexus occupies a considerable area in Tipula; but is much
reduced in Stratiomys.
As in the Vertebrata, all the branches of the plexus are situated
between the sarcolemma and the contractile mass; they seem to
terminate in a slender point as in the frog.
Special nuclei are adherent to the branches of the plexus, and
* «These pour le Doctorat en Medicine,’ 8vo, Paris, 1881 (45 pp. and 3 pls.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 30
accompany them throughout their course. These the author calls
“ nuclei of the plexus” (noyaua de Tarborisation), comparing them to
those so named in the Vertebrata.
In Tipula there is attached to the principal branches of the plexus
a granular substance provided with special nuclei, which must be
compared to the “ fundamental nuclei” and “ granular substances” of
the plexus of the higher Vertebrata. They are completely wanting
in Stratiomys.
Between the plexus of Stratiomys and Tipula there exists a differ-
ence analogous to that observable between the plexus of the frog and
that of the lizard.
These results do not necessarily invalidate, the author says, those
of Ranvier and Foettinger, because he has dealt with a histologically
different matter. They confirm, however, the observations of Rouget,
-who has described the axis-cylinder as forking in the interior of the
cone, the two branches of the fork being applied to the surface of the
contractile mass but not appearing to extend further. They also
confirm his view that the granular matter which fills the cone is of
little importance, being absent in Sératiomys.
Wings of Insects.*—Dr. G. E. Adolph figures a large number
of wings chiefly of Hymenoptera, and points out that the arrange-
ment of the concave and convex lines is the most constant character,
but that the concave are much more persistent than the convex. A
study of the arrangements seen in Vanessa has shown him that the
tracheal system of the wing is first developed along certain primary
lines, the most primitive and striking peculiarity of which is their
tracheal nature; between these there are developed certain costal
elements. After dealing with the Lepidoptera he passes to the
Diptera, and in their case, as in that of the Neuroptera, he institutes a
comparison with the Hymenoptera, pointing out how fresh branches
become developed and earlier nervules absorbed.
In a second paper { he deals with certain abnormal developments
in the wings of some Hymenoptera.
Structure of the Proboscis of Lepidoptera.t—W. Breitenbach,
dealing with the phylogeny of this organ, finds in the early stages of
the insect indications of its origin, for in the late larva it has been
found already represented by two long curved cords. But further, the
obvious connections of the group with the Trichoptera show that the
biting mouth of the latter has produced the sucking tube of the former
by modification of the labium, maxille, and labrum, which were at
first all united into a tubular organ; the edges of the two maxille
then became more closely approximated, and the share of the other
two parts in the organ became unnecessary, and they were excluded
from it. This metamorphosis, however, was probably made in various
stages, each having some definite advantage to the insect as its object:
e.g. the exclusion of the labrum and labium from the organ was a
ty é Nova Acta Acad. Ces, Leop.-Carol. Germ. Nat. Cur., xli. ii. (1880) pp. 213-
6 pls.).
+ Tom. cit. pp. 293-328 (1 pl.).
¢ Jenaisch. Zeitschr. Nat., xv. (1881) pp. 151-214 (3 pls.).
36 SUMMARY OF CURRENT RESEARCHES RELATING TO
beneficial simplification, the great object being to bring the two
maxille together; the latter organs were able to assume a greater
development in consequence of the reduction of the former; this
development was further promoted by the abnormal method by which
food was obtained. The increase in the length of the tube was caused by
the depth which the nectaries of certain flowers exhibited, and by which
they excluded insects hurtful to them, while, at the same time, this
very depth allowed of the accumulation of a greater amount of honey.
The transverse striation of the tube, noticed by Réaumur, is
produced by semilunar bands of chitin, which are set side by side
from the root to the extremity of each half-tube in two series of
half-hoops, exterior and interior; the degree of their development
varies in different insects; they are most slender at the apex, a fact
which is partly due to the space occupied by certain papilloid pro-
cesses on this part. The form of the bands also varies; in some
Lepidoptera they are broken up into a series of separate chitinous
pieces; sometimes, as Gerstfeldt has observed, they are forked, but
in this case they are divided only into two arms, not three, as stated
by that observer. The transition from the condition in which the
bands are composed of series of separate pieces to that in which
they form continuous strips is well seen in passing from Pieris to
Vanessa, though even in the latter genus (e.g. V. cardui) the trans-
verse chitinous series are not wholly united into bands. It is un-
certain whether the disconnected or the consolidated form of the
chitinous bands of the tube is the primitive condition. The apposed
edges of the two halves of the tube may be either serrate (Egybolia)
or plain (Argynnis).
The apex of the proboscis presents, as already well known, certain
organs called juice-borers. The simplest form of these is (1) that of
simple hairs, which occur on every proboscis, and consist of a basal
chitinous ring, the “cylinder,” and a true hair-shaft, which is
traversed by a horny mass, the “axial radius,” termed “central mass”
in the juice-borers; the cylinder is usually imbedded in the main
substance of the tube. When true sap-borers coexist with them, the
hairs are short, and vice versd. The varieties in form of the juice-
borers are caused by varieties in the peripheral portion of the shaft.
2. Juice-borers, with the upper edge of cylinder dentate, e. g. Vanessa.
Cylindrical or barrel-shaped, the teeth are six to eight in number,
moderately sharp; in Pyrameis virginiensis they are cylindrical,
laterally compressed. 3. Juice-borers with longitudinal ridges formed
by the chitinous covering of the “central mass” which spreads out
into six plates, running parallel to its axis, e. g. Catocala, Noctua,
Plusia, Mamestra, Agrotis, Triphena, Phlogophora, ‘Tceniocampa,
Euclidia, &e. 4. Juice-borers of is sufficient to distinguish
A. calamaria as a monacanthid, polyplacid, heteractinid form. “If
we know, as we do in this case, further details, we may write the
formula 1 paa’; or, in other words, in addition A. calamaria
has no spines round its madreporic plate, and the dorsal spines are
placed on special plates.”
The author then makes some observations on the species of
Asterias, found in the British seas, and concludes with the description
of five new species: A. philippii, A. inermis, A. verrilli, A. spirabilis,
and A. rollestoni, for all of which, as also for A. japonica, of which a
description is given, the author gives the “ general formula.”
Spines of Asteroidea.*—At the conclusion of a description of a
new species of Archaster (A. magnificus), Professor F. J. Bell points
out that in littoral species, at any rate, the strength and number of
the spines is in inverse proportion to the stoutness of the skeletal
plates; when these are strong the star-fish is enabled to withstand
the bite of an enemy ; but when they are weaker, a defensive apparatus
is provided in longer, stronger, and stouter spines.
Ccelenterata.
Prodrome of the Anthozoan Fauna of Naples.t—-Dr. A. Andres
here gives a systematic catalogue of the species, with synonymy, «c.,
* Ann. and Mag. Nat. Hist., viii. (1881) pp. 440-1.
+ MT. Zool. Stat. Neapel, ii, (1881) pp. 305-71.
58 SUMMARY OF CURRENT RESEARCHES RELATING TO
an alphabetical index of species and synonyms, a bibliographical list,
and an index of authors.
Metamorphoses of Cassiopeia borbonica.*— Professor G. Du Plessis
has observed ova of what he believes to be this species, develope into
a fixed Scyphistoma, after passing through a free Planula-stage.
Other larve of similar appearance, which had already attained the
Scyphistoma-stage, were studied by him at the Naples Aquarium, and
were seen in the middle of October to divide metamerically into
segments, forming the well-known Strobila-stage. The segments
soon became detached, constituting free Ephyre of a similar, but
paler, yellow tint to that of the adult of the above species, but differ-
ing from it in having four simple and suckerless, instead of eight
ramified arms, and in having the margin of the umbrella much more
deeply notched. In this instance also, the attempt to rear the adult
failed, but as the only other species whose stages resemble these, has
quite a different Ephyra, there seems good ground for believing that
we have here the full metamorphosis of a Medusa, supposed hitherto
to develope ametabolically. In the agreement of its physiological
arrangements with those groups with which it has hitherto been
classed, it affords an argument in favour of the morphological correct-
ness of the present classification.
Development of Geryonopsida and Eucopida.}t—-Professor C. Claus
states that in an aquarium containing sexually mature specimens of
Octorchis gegenbauri, Irene pellucida, and Aiquorea forskalea, he saw
small polyp-stocks which presented great resemblance to Campa-
nulina; the elongated hydranths were placed on branched stolons,
the periphery of which was invested by a more or less distinct
periderm. ‘There was a conical retractile proboscis, and the base of
the contractile tentacles was surrounded by a delicate ectodermal
fringe. Hydrathecz were, however, altogether wanting; this and
other differences induce the author to call this form Campanopsis.
The medusa-buds arise on the middle of the body of the polyp, where
they form one, two, or, rarely, three transverse rows; they appear as
bilaminate rounded projections, the base of which soon grows into a
long cylindrical stalk, with a vesicular endoderm. Before the forma-
tion of the subumbrellar cavity, the ectoderm gives rise to a layer of
flat cells, which form the theca, and give rise to a closed mantle-
covering. The manubrium is formed from a central elevation; the
radial vessels give rise to outgrowths, which are the rudiments of
the primary marginal tentacles. In alternate rays, as well as between
these and the primary tentacles, marginal vesicles become developed
with small intermediate thickenings—the rudiments of fresh marginal
filaments. When, therefore, the medusa is set free, it has two long
tentacles and eight adradial marginal auditory vesicles. These last,
which are relatively large, contain each a single otolith. At this
point, unfortunately, the author’s direct observations cease, but he
adduces reasons for believing that this Campanopsis is an Octorchis.
* Bull. Soc. Vaudoise Sci. Nat., xvii. (1881) pp. 633-8 (1 pl.).
+ Arbeit. Zool. Inst. Wien, iv. (1881) pp. 89-120 (4 pls.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 59
In some notes on the development of Irene pellucida, which is so
common in the Adriatic from October to March, Claus states that
it is possible that the polyp-form of this Medusa is a Campanulina.
The first rudiment of the tentacles appears as an outgrowth, present-
ing brownish granular concretions, and having a pore at its tip;
these pores are looked upon as being the orifices for subjacent glands,
which probably have the function of renal organs, and which are
formed by the endodermal investment of the adjacent portion of the
circular vessel; by direct observation one may convince oneself that
the brown granules and refractive concretions do escape by these
pores to the exterior. The genital products appear to become matured
im specimens of very various sizes. Some notes on Phialidium
variabile complete the paper.
Fission of Phialidium variabile.*—Dr. M. Davidoff states that
he has observed in this Leptomedusa that a second stomogastrium
becomes formed at the base of the stomach as a small downwardly
projecting bud; this happens before the tentacles are all developed.
The bud gradually grows, and after some time a mouth breaks
through. The whole medusa now commences to elongate, and the
stomogastria occupy the centres of the ellipse; two radial canals
now open into each stomach and between the two mouths there is
an intergastral canal. After these and other changes are effected,
the creature is ripe for fission ; the plane of division lies between the
two stomogastria, and almost always at right angles to the long axis
of the ellipse; the constrictions deepening, the medusa is divided
into two nearly equal halves. In some cases there is a third stomo-
gastrium developed. The author reminds us that Kélliker, many
years ago, noticed a process of fission in Stomobrachium mirabile.
Crambessa tagi.t—Professor R. Greef points out that this
Portuguese Medusa affects the mouths of rivers, and makes its way
into landlocked bays. He has found a wide vessel running within the
oral fold; the two pairs of vascular branches which are given off
from the short central transverse vessel, open, together with the eight
arm-yessels, in the central cavity ; the outgrowths above these central
oral vessels have just the same structure as the lobes of the arms,
into which they pass directly, and may therefore be regarded as
“sucking knobs” or oral frills. Hach of the eight arm-vessels
divides into four longitudinal vessels, one of which is median; the
three peripheral ones are connected by transverse anastomoses with
the axial, and give off branches to the appended lobes.
The eight sensory organs agree in their external and general
internal structure with those of the Hertwigs’ second group of
Acraspedota; the terminal network, in which the crystals lie, is
regarded by the Hertwigs as being formed from the vessel which
runs along the arm; Greef, however, thinks that this plexus is
formed from the mesoderm, while the nerve-band breaks up into a
fine nucleated plexus, which makes its way into the meshwork which
* Zool. Anzeig., iv. (1881) pp. 620-2.
t Ibid., pp. 568-70.
60 SUMMARY OF CURRENT RESEARCHES RELATING TO
supports the crystals, and so comes into contact with them. In the
upper wall of the terminal knob the author was able to detect an
ocellus.
Sexual Cells of Hydroida.*—A. Weissmann finds that these are
ectodermal in origin, but he allows that in some cases they are
developed in the endoderm, and that in others the spermatozoa are
ectodermal and the ova endodermal in origin ; and he also recognizes
the cceenosarcal origin of the elements in some cases. Together with
this ccenosarcal origin, there may be development from cells situated
in the sexual buds (blastoid origin), and Hydrozoa may therefore be
spoken of as cenogenous (abbreviated from ccenosarcogenous), or as
blastogenous ; and the author insists on the correctness of the view
that in some cases the germ-cells are not developed until the medusa
is completely formed.
The chief object of the present communication is to demonstrate
that the sexual cells which arise in the ccenosare are normal produc-
tions of great significance, and that in all such cases the coenosare and
not the gonophores is to be looked upon as the true seat of the cells ;
and, further, to show that this mode of reproduction is very common,
there being entire families in which the ova are so formed; while
there are others in which the testicular products also are so developed.
Of the latter, Plumularia (e.g. P. echinulata) is an example, for in it
the cells are developed in the endoderm, principally of the trunk
portion, but often also at the base of the lateral branches of the
coenosare. The formation of the male and female gonangia is
described in detail, and shown to be similar for both.
Gonothyrcea loveni is the first example of the Campanularide, and
here the male elements are ectodermal, and arise, not in the ccenosare,
but in the gonophores, from an invaginated set of ectodermal cells.
The ova, on the other hand, are formed from the endoderm of the
ccenosare and of the branches. In Hudendrium ramosum they are
both formed from the endoderm, but the male elements are of
blastoidal and the female of ccenosarcal origin. In Cordylophora
lacustris, as Schulze was the first to show, the ova are ccenosarcal and
ectodermal ; the origin of the male elements has not been accurately
worked out.
We find, then, certainly that in most (cf. next note) polyps with
fixed gonophores the ovules do not arise in the gonophores but in the
coenosare, and their appearance is the condition of the formation of a
gonophore, into which they migrate. There is more variation in the
male products, which do not appear to be so constantly ccenogenous;
where, however, they are so, the development of the gonophore and
the migration of the testes into them is essentially similar to that of
the ovaries.
Spermatozoa of Hydrozoa.t— A. de Varenne has examined
Campanularia flexuosa, Gonothyrea loveni, and Podocoryne carnea, in
which are found respectively a fixed gonophore, a demi-medusa, and
* Ann, Sei. Nat. (Zool.), xi. (1881) art. 6, 33 pp. (3 pls.).
t+ Comptes Rendus, xciii. (1881) pp. 1032-4.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 61
a free medusa. In all cases the mother-cells do not appear in
any part of the gonophore, but in the ccenosare. Taking the first-
named species, he found that before the appearance of any gono-
phore large highly-refractive cells appear in the endoderm of the
ceenosare ; the presence of a certain number of these mother-cells
determines the formation of a gonophore. Very soon the primary
mother-cells multiply with great rapidity, and the daughter-cells,
which are much smaller, form a horseshoe-shaped testicular mass,
which, growing rapidly, ceases to form part of the endodermic wall,
owing to the reconstitution of the unaltered endodermal cells, which
now form a continuous layer below it. This explains the origin of
the statement that the testicular cells are ectodermic in origin.
There is, further, a great similarity between the development of the
male and female elements. The author thinks that there is no true
alternation of generations.
Porifera.
Attempt to Apply Shorthand to Sponges.*—The system here
elaborated by Dr. G. C. J. Vosmaer is an extension of that first intro-
duced by him in a paper on the Desmacidine of the Leyden Museum,t+
and its object is to give shortly the characters of a sponge by symbols
which denote its several spicules. In the present scheme he tries to
make his system of symbols so elastic as to admit almost any possible
combination of characters in a spicule. Of course it is only applicable
to sponges which have spicules, and does not take account of the
Carnosa or the Horny Sponges; neither does if take account of the
proportions (though the worker may readily add these himself); the
author admits that it is not applicable to all cases, but claims for
it the recommendation of saving some time and trouble in description.
It is impossible to give here all the full formule used, so that in most
cases only the abbreviations are given, which can be combined
according to the requirements of different cases, and may help
students of sponges to arrange for their own use, at any rate, methods
of expressing shortly the often complicated spicular complements
which may be met with. Dr. Vosmaer has used it for three years.
For monaxial (i.e. linear) spicules are used :—tr (truncate) =
blunt-ended ; ¢r tr = blunt at both ends, but not to same extent; tr ac
(acute) = blunt at one end, pointed at the other (acuate, Bowerbank) ;
acac = doubly-pointed, to different extents. Where the forms of the
ends are similar, the formula is fr, ac*, &c.; tr® tr = clavate or
spinulate cylindrical, and tr° ac stands for the common spinulate or
“ pin-like ” form; f = fusiform, sp = spined. Combinations of these
signs supply formule for the thirty-two modifications of straight mon-
axial spicules. For curved forms of the same group the following
abbreviations are used. An inverted V (/\) for the tricurvate acerate,
an § on its side (®) for the bihamate; the same with two lines
drawn across it, so as to make it resemble the sign for a dollar, stands
for trenchant contort bihamate ; anc is anchorate, anc* is tridentate
* Tijdsch. Niederl. Dierk. Vereen., v. (1881) pp. 197-206 (1 pl.).
+ See this Journal, iii. (1880) p. 661.
62 SUMMARY OF CURRENT RESEARCHES RELATING TO
anchorate, anc?3 being tridentate equi-, and anc anc 3 tridentate
inequianchorate; anc 2 is bidentate anchorate. Rut (rutrum, a
shovel) palmated anchorate.
For the Hewactinellid, or, as Vosmaer prefers to call them,
Triactinellid, types (those with three distinct axes), the general de-
nomination is ha (initials of é£ and afwv) ; the different radii are desig-
nated by R or r; thus when four of the six rays are small and two
large, the formula for the spicule is (4r-++ 2B); sp may be added
for spined. Where the spicules are fixed, i.e. skeletal, a line is
drawn over the formula; thus the skeleton spicule of Farrea becomes
ha (4R-+ 2rsp); but the “fir-trees” of Hyalonema, &c., become
ha (4r + Rf sp).
For Tetractinellid forms the general sign ta is used (réocapes,
aéwv); in the common case in which one ray is longer or shorter
than the rest, this odd ray is termed M (manubrium), and the others
d (dentes); if these are bifurcate, bif is added to d. For the angles,
that which M makes with the three d’s—almost the only angle which
varies—is termed 6; > is greater than, < is less than. A triradiate,
being reckoned as a tetractinellid with one ray aborted, is expressed
by ta (M = 0). Thus porrecto-ternate of Bowerbank is ta (6 > 90°),
patento-ternate is ta (p = 90°), recurvo-ternate (¢@ < 90°); bifurcated-
ternate is ta. d. bif. If necessary, such a formula as ta (¢ > 90°)
d. bif (d' > d < M) could be used, where the three rays are bifureate
and of different sizes, but less than the odd ray.
Polyaxial forms, i.e. globates and stellates, may be termed gl
(globulus) or s¢ (stella), globo-stellates (with large ball for a centre)
gl. st. For the spiral or double stellate (e.g. of some Suberitide), st?
is employed.
Protozoa.
Flagellata.*—J. Kiinstler states that in an incubating chamber
Cryptomonas ovata germs found at different stages in development
presented the following characters. The less advanced were formed
by a nucleolus surrounded by a layer of protoplasm; soon one of their
poles developed more rapidly than the other, and elongated. After
it had reached a certain size it gave rise at its free extremity to an
axial cord of protoplasm, which constitutes the first stage of the diges-
tive tube. Here there appear some large vacuoles, which divide and
rapidly multiply, and soon a cavity commences to be developed in the
body, beginning as a lateral space, one on either side. In Chilomonas
paramecium there is, similarly, a vestibule to the digestive tube, an
antero-lateral constriction, locomotor, striated, and other prehensile
flagella, a stomach with granular walls, an intestine terminating in
an anus, four tegumentary layers, and a nucleus with several nucleoli,
whence is given off a tube which dilates into the incubating chamber
in which the germs are developed. In Chlamydomonas pulvisculus
there are four, and not two, striated flagella, which are inserted
around an orifice leading into a small cavity, and giving off delicate
tubes to the contractile vesicles.
A new species is Astasia costata, the ribbed form of which is due
* Comptes Rendus, xciii. (1881) pp. 746-8.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 63
to the presence in their integument of regular rows of starch-grains.
In this form the digestive apparatus consists of a narrow cesophagus, a
large gastric pouch, the walls of which were not detected, and an
intestine leading to an anus. A new generic form is represented by
Kiinckelia gyrans, which is a fresh-water Noctiluca. The body is
capable of elongation, and so is enabled to creep about. There is an
enormous tentacle which exhibits very active movement when the
animal isswimming. Under its cuticle there are two muscular layers,
which are continued into the tentacle. The mouth appears to lead
into a very large cavity. No phosphorescence has yet been observed
in this form.
Infusoria Parasitic in Cephalopods.*—In an elaborate memoir,
A. Foettinger enters more into detail into some of the characters of
these forms.t In dealing with the suspected muscular fibrils, he says
that in optical section they reveal themselves as bright spots, set at
equal distances from one another, and placed near the cuticular
envelope. ‘They give rise to the appearance of a transverse striation;
and these striz, of which there are two systems, become both visible
when the cover-glass is compressed on the animal. ‘T'he differences
in the position of the fibrils is due to a difference in their state of con-
traction ; for as they contract their obliquity diminishes, and the part
of the body which contains them becomes shorter and wider. In one
case the author observed in Benedenia a nucleus extending through-
out the whole length of the body. He regards the nucleus, the
characters of which have been already detailed, as not forming a fixed
element, but one gifted with the power of amcboid movements.
Opalinopsis sepiole was on one occasion observed to conjugate and
reproduce while in sea water, so that in this case we can see how the
parasite may pass from one Cephalopod to another.
Parasites of the Echiurida.t—Professor R. Greef describes Cono-
rhynchus gibbosus nov. gen. et sp.,a large Gregarine to which he pre-
viously gave the name of Gregarina echiuri. The creature, which
lives in the digestive canal, is nearly always found, when adult, in
conjugation. Hach individual forms a hemispherical disk, and its
surface is provided with a number of conical and warty projections.
At the anterior end there is a considerable process which appears
to serve as an organ of attachment; the form is completely trans-
parent owing to the great development of vacuoles. There is a large
nucleus. In size each adult is about 1 mm. long and 1 mm. broad.
In the youngest stage observed, the Gregarine had the form of a Mono-
cystis agilis, and the internal substance was opaque and darkly
granular. Distomum echiuri n. sp., found in the seminal vesicles of
Echiurus pallasi, is 2 mm. long, and is continued forwards anteriorly
into a proboscidiform process. Nemertoscolex parasiticus n. gen. et
sp., is a Nemertine of about 3 mm. long, found twice in the ceelom of
E. pallasi, in the male as well as in the female.
* Arch. de Biol., ii. 1881) pp. 345-78 (4 pls.)
+ See this Journal, i. (1881) p. 902.
¢ Nova Acta Acad. Cas. Leop.-Carol. Germ. Nat. Cur., xli. ii. (1880) ‘pp.
128-131, with figs.
64 SUMMARY OF CURRENT RESEARCHES RELATING TO
BOTANY.
A. GENERAL, including Embryology and Histology of the
Phanerogamia.
Origin of the Embryo-sac and Functions of the Antipodal
Cells.*—-After referring to the views on these subjects already pub-
lished by Warming, Vesque, Strasburger, Fischer, Ward, and Treub,t
L. Guignard details a series of observations of his own on a variety of
plants, to determine some of the controverted points.
As a type of the Mimosez, in which the phenomena are remark-
ably uniform, he takes Acacia retinoides. At the summit of the
nucellus, beneath the epidermis, an axial cell, somewhat larger than
the adjoining ones, divides into two superposed cells; one, the origin
of the cap (calotte) in Dialypetale, in immediate contact with the
epidermis ; the other Warming’s primordial mother-cell of the embryo-
sac, situated at a greater depth; these he calls the apical and sub-
apical cells. The apical cell gives birth to a tissue which is generally
reduced to three broad cellular layers. The subapical cell rapidly
enlarges, and becomes segmented horizontally in the basipetal direc-
tion, dividing thus into three superposed cells each equal in size to
the mother-cell. Of these the lowest is alone the true mother-cell of
the embryo-sac, enlarging at the expense of the others and of the
lateral nucellar tissue. The nucleus increases in size, and beeomes
surrounded at first by granular protoplasm, then by grains of starch,
which finally often entirely fill up the cell-cavity. Resorption soon
commences in the two superposed cells; their nuclei lose their sharp
outline, the cell-walls disappear, and the entire protoplasm has the
appearance of a homogeneous and refractive mass, the nuclei be-
coming indistinguishable ; finally the whole substance of these cells
is absorbed in the development of the lower mother-cell.
This process is subject to certain variations; but it is always the
lower cell which becomes the mother-cell, and absorbs the others.
The starch-grains disappear during the formation of the eight nuclei
which give rise to the synergide, the oosphere, the antipodal cells,
and the two polar nuclei which coalesce in order to form the secondary
nucleus of the embryo-sac.
In the Cxsalpiniez the apical cell generally gives rise to a thick
tissue which remains for a considerable time, even after impregnation.
Variations occur in the subsequent development; and these are
greater among the Papilionacez, not only in genera of the same tribe,
but even in species of the same genus. In this order the apical cell
gives rise only to two superposed cells; the subapical cell remains
undivided, increases early, and displaces the others.
As a general result, whatever may be the differences in the origin
and number of the cells which constitute the axial row of the nucellus,
it is the inferior cell only which is the true mother-cell of the embryo-
* Bull. Soc. Bot. France, xxviii. (1881) pp. 197-201.
+ See this Journal, ii. (1879) p. 903; iii. (1880) pp. 107, 979; i. (1881) pp.
260, 620.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 65
sac; there is never any coalescence between two adjoining cells. In
all the Leguminose the synergide and oosphere, the antipodal cells,
and the secondary nucleus of the embryo-sac, are formed in the well-
known mode. The antipodals often disappear after impregnation, in
consequence of the resorption of the subjacent nucellar tissue. Their
function, which is still very doubtful, seems to terminate shortly after
their formation. In other orders of plants, on the contrary, they in-
crease considerably, even after impregnation. As in the majority of
Angiosperms, there are no anticlinals, the mother-cell of the embryo-
sac being the last of the row.
The presence of two nuclei in one or more cells, as in Cercis,
does not furnish any real analogy with the special mother-cells of
pollen-grains, because their division-walls are never completely
resorbed.
Antipodals with several nuclei occur in some Ranunculaces, as
Clematis and Hepatica triloba. The cells are always three in number,
and are inserted at the base of the embryo-sac, to which they are
attached by a kind of pedicel. Each of them has a nucleus containing
at first a single nucleolus. Long before impregnation two nucleoli
appear (in the hepatica) isolated in the substance of the nucleus; there
is an internal line of separation between them corresponding to a
slight depression on the surface, which gradually deepens, and finally
divides the mother-nucleus into two parts, in which the same pheno-
menon may then be repeated, though this is not usually the case.
The whole then presents the form of four segments, in which the
nucleoli multiply ; and the protoplasm itself may be divided into five,
six, or even eight rounded fragments. The nucleoli do not elongate
into an hour-glass form, nor does the substance of the nucleus present
any median constriction, as is generally the case in fragmentation ;
they are rather granulations of the nuclear protoplasm, which soon
attain a considerable size. Finally the mother-nucleus is filled with
granular nucleoli, and becomes enveloped in the protoplasm.
There appears, therefore, to be a special process of fragmentation
in organs whose function is completed, and which may be regarded
either as an organic residuum or as a degraded prothallium.
Polyembryony in Mimosex.*—According to L. Guignard, poly-
embryony is a not uncommon phenomenon in the Mimosee, especially
in Schranckia uncinata and Mimosa Denhartii, and is allied, in the
former case, with other abnormalities of structure.
In S. uncinata the tigellum is furnished, towards its extremity,
with an appendage of variable form, lobed, and descending below the
cap which clothes the embryonal radicle. The internal structure of
this appendage presents several interesting peculiarities. In addition,
several embryos, formed of an internal normal structural axis, and
furnished, or not, with this appendage, present three or even four.
foliaceous cotyledons of equal length folded longitudinally in various
ways. When the number of cotyledons is three, they occupy the
angles of an equilateral triangle, and one of them is inserted at a
* Bull. Soc. Bot. France, xxviii. (1881) pp. 177-9.
Ser. 2.— Von. II. F
66 SUMMARY OF CURRENT RESEARCHES RELATING TO
different level from the others; when the number is four, they are
arranged in two opposite pairs at different levels. Instead of a single
tigellum, there are often two of equal size, united in growth during
the greater part of their length, but distinct towards the base. One
of these axes occupies the normal position, the other being applied to
it laterally.
The appendage is undoubtedly a reserve of food-material. When.
a seed possessing it germinates, it is exposed along with the radicular
extremity, increases for some time after the rupture of the testa, then
gradually loses its starch, which it gives up to the embryo, and finally
dries up and perishes.
Resistance of Seeds to extreme Cold.* — E. Wartmann has ex-
posed fresh-gathered Spanish chestnuts for nearly two hours to a cold
of at least — 110°, derived from a mixture of sulphuric ether and solid
carbonic acid, each seed being carefully wrapped in thin tinfoil, so as
to prevent the surface coming into contact with the ether. The chest-
nuts were then planted in the soil; they germinated and developed in
every respect as successfully as those which had not been exposed to
the cold. The power of resistance to extreme cold appears, indeed, to
be a very general property of seeds.
Mechanical Contrivances for the Dispersion of Seeds and
Fruits.j;—A. Zimmermann has subjected to a fresh examination the
structure of the seed-vessels of Graminew, Papilionacex, and Gera-
niacez, by the torsion of which the seeds are buried in the soil,
especially in relation to the alternate turgidity and desiccation of the
tissues. His conclusions, which are mainly in accord with those of
C. and F. Darwin, are as follows :—
1. The hygroscopic torsion of the awns of Graminez is the result
of the effort after torsion of the outer cells of the stereome, and of the
strong contraction of its inner cells, which probably assist by the
fact that when they swell they assume an oblique position. The
micella of the former cells are arranged in spiral lines, those of the
latter in oblique rings.
2. The effort after torsion of a single spirally striated cell is
caused by unequal intensity of swelling and unequal firmness in the
direction of the two systems of rows of micella. The swelling of an
imaginary cylinder without thickness causes in general a torsion in
the direction in which there is the strongest swelling. The radial
swelling of a cylinder possessing thickness, causes, when it is strongest,
a torsion in its outermost layers in the direction of less firmness; in
the inner layers, one in an opposite direction. The most probable
explanation of the fact that a cell in which the most strongly marked
striations and pores are arranged in spirals inclined obliquely to the
left, turns itself to the right when it swells, to the left when it dries
up, is that on the one hand the swelling is strongest in a direction
vertical to these striations and to that of the pores; on the other
* Arch. Sci. Phys. et Nat., v. (1881) p. 343. See Naturforscher, xiv. (1881)
p. 276.
+ Pringsheim’s Jahrb. wiss. Bot., xii. (1881) pp. 542-77 (8 pls.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 67
hand, the firmness is greatest in the direction of the rows of micella
and of the pores.
3. The cause of the torsion of the legumes of Orobus and
Caragana resides in the layer of resin, and is brought about in it by
unequal contraction in the transverse direction, which is indicated
_by anatomical differences. The outer epidermis (and its anatomical
strengthening in Caragana) acts only by increasing the strength of
the mechanism, the vascular bundles of the margin detracting from
its efficiency.
4, The torsion of the awns of Geranium is caused by unequal con-
traction of the cells in the longitudinal direction, these cells manifesting
also differences in the form and direction of their pores. In the awns
of Pelargonium the outer strongly developed epidermis effects the
torsion by strong curvature, the direction of the torsion being ren-
dered spiral by the tendency to torsion of the inner cells.
5. The violent expulsion of the seeds of Ovalis is not caused by
turgidity, but by the energetic swelling of the cell-walls of the trans-
parent outer layer.
Chemical Difference between dead and living Protoplasm.—
The view maintained by O. Loew and T. Bokorny,* that living cells
are chemically different from dead ones, in that living protoplasm
shows an aldehyde nature by its power of reducing extremely dilute
alkaline silver solutions, while dead protoplasm does not, has been
the subject of an interesting discussion at the Berlin Chemical Society,
when Herr Reinke denied the chemical difference, and insisted that
at least a part of the reaction is due to a volatile substance of alde-
hyde nature which is very frequent in green cells, and which he is
disposed to regard as formic aldehyde, the first product of assimilation
of carbonic acid in the plant.
His opponents urged that they had carefully examined the dis-
tillation products of various species of Algz and of germs without
chlorophyll, but had quite failed to find any silver-reducing sub-
stance. Thinking, further, that they might have been misled by the
action of sugar or tannin, they convinced themselves that cells reduce
which have neither of these substances, and a living cell will easily
reduce a very dilute silver solution which sugar and tannin fail to
reduce. The intimate relation between silver-reducing power and
life (in their opinion) is shown clearly by the fact that in whichever
of many different ways cells of Algz were killed, the reaction in
question ceased with their death, and precisely at the degree of
temperature at which life is extinguished. This is generally the case
in killing by poison; strychnine alone being an exception, which is
explained by the existence of a combination of the alkaloid with
molecules of the active albumen.
Energy of Growth of the Apical Cell and of the youngest
Segments.j—M. Westermaier commences a dissertation on this subject
with an historical sketch. Naegeli and Schleiden attributed the causes
* See this Journal, i. (1881) p. 906.
+ Pringsheim’s Jahrb. wiss. Bot., xii. (1881) pp. 439-72 (1 pl.).
F 2
68 SUMMARY OF CURRENT RESEARCHES RELATING TO
of the form of any particular part of a plant to the individual cells,
so that the individual cell plays a prominent part, and the behaviour
of these determines the form of the organ. A different view is held
by Hofmeister, Sachs, De Bary, and Hanstein, who regard as the
primary fact the form of the organ itself, which then determines the
form and mode of division of the cells. An intermediate position
between the two is held by Schwendener; the arrangement of the
cells and the directions of the dividing walls being, according to him,
determined by two variable factors :—(1) by the individuality of the
cell; (2) by the form or complete growth of the entire organ, to
which Schwendener also attributes a share in the arrangement and
growth of cells. The final position of the walls and arrangement of
the cells is often also influenced by pressure.
In order to determine the relative energies of growth of the cells
of the apical region, the author proposes the following theoretical
considerations :—
1. “The apical cell displays the same activity with regard to
increase in volume during successive stages.” By a stage the author
means the time which elapses between the formation of a division-
wall in the apical cell and the formation of the next following
division-wall.
2. “The successive segments display an equal activity with
regard to increase in volume during successive stages.” In this con-
nection the relationship is investigated between the volume and the
projection of the lateral profile of a triangular pyramidal and of a
two-edged apical cell.
After these theoretical propositions, a comparison is made of the
energy of growth of the apical cell in Dictyota (according to Naegeli),
Hypoglossum Leprieurti (Naegeli), Metzgeria furcata (Goebel), Salvinia
natans (Pringsheim), Equisetum arvense (Cramer), E. scirpoides (Reess),
and Selaginella Martensii (Pfeffer).
The general result is stated as follows: —'The maximum of
increase in volume lies in general either in the apical cell itself or in
the youngest segments. If we look only at the region which in-
cludes the apical cell and the four youngest segments, in none of the
cases mentioned above is the increase of volume least in the apical
cell.
Action of Nitrous Oxide on Vegetable Cells.*—Prof. W. Detmer
has tried a series of experiments on the influence on vegetable tissues
of nitrous oxide gas, which he states may, to a certain extent, replace
oxygen in the respiration of plants. For this purpose he took pains
to obtain the gas absolutely pure, and carefully to exclude every trace
of atmospheric air. The main results of his experiments, made on
Triticum vulgare and Pisum sativum, are as follows :—
1. When grains of wheat or peas are made to swell in water which
has been boiled and allowed to cool, and then placed for a considerable
time in contact with pure nitrous oxide, they lose their power of
germination.
* SB. Jenaisch. Ges. Med. u. Naturwiss., 1881, July 1. See Bot. Ztg., xxxix.
(1881) p. 677.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 69
2. If their contact with the gas is not so long, say from one to
three days, they do not entirely lose the power of germinating; the
embryo will begin to develope under normal conditions,
3. A longer contact with the gas kills the cells.
4, In a mixture of two parts by measure of nitrous oxide and one
part of atmospheric air, the power of germination of peas is yery
greatly weakened.
5. If peas have been made to germinate under ordinary conditions,
and then brought into pure nitrous oxide, no further development
whatever of the root and stem takes place.
6. In pure nitrous oxide no geotropic or heliotropic curvatures
take place.
7. Etiolated parts of plants do not become green in the light if
surrounded by an atmosphere of pure nitrous oxide.
8. A number of experiments prove that vitally active cells are not
able to decompose nitrous oxide; and that they therefore have no
power of using its oxygen for the purpose of respiration.
Chlorophyll and the Cell-Nucleus.*—G. Schaarschmidt makes the
following observations :—
1. Division of chlorophyll. The mode of division of the
chlorophyll-grains resembles that of the nucleus, and takes place
either directly by constriction, or indirectly by division with forma-
tion of threads. All green chlorophyll-grains divide in one or other
of these ways, as does also the endochrome of diatoms, as, for example,
the coccochrome of Odontidium vulgare, and the placochrome of
Himantidium pectinale.
2. Hypochlorin occurs also in the Cryptophycee and diatoms.
When WNostoc, Microcoleus, Merismopedium, and Oscillaria, had been
treated for two days with concentrated, and then for four days with
dilute hydrochloric acid, and preserved in it, three, four, or more
minute rusty-brown masses made their appearance on the surface of
the cells, which showed the characteristic properties of hypochlorin.
The endochrome of diatoms treated in the same way becomes dirty
green, and assumes a spongy structure, hypochlorin appearing at the
margins in the form of irregular brown masses. This occurred in
Cymatopleura Solla, Himantidium pectinale, Synedra splendens, Pinnu-
laria viridis, P. radiosa, &c., and especially in Synedra ulne. The
reactions were not, however, successful in every individual.
3. The cell-nucleus of Nostoc. A small round body was observed
in the cells of Nostoc, usually in contact with the division-walls, and
which showed beautiful phases in the division of the cells, When
the cell has elongated and is ready for division, this body parts in
the middle, a colourless central zone being thus formed in the midst
of the colouring substance. When oblong cells are placed in coloured
alcohol-material, the nucleus is constricted ; the constriction becomes
gradually deeper, and a furrow appears on the outside of the cell.
* Schaarschmidt, G., ‘ Morphology of Chlorophyll and of the Vegetable Cell-
nucleus’ (in Magyar); with drawings and a photogram. 56 pp. Klausenburg,
1881. See Bot. Centralbl., vii. (1881) p. 263.
70 SUMMARY OF CURRENT RESEARCHES RELATING TO
Finally the daughter-nuclei divide, and are kept together only by a
narrow bridge; when the cell-division is complete, these nuclei are
found again on the division-walls. The diameter of these minute
bodies is only from 0°5 to 0°6 »; their behaviour when dividing and
towards colouring reagents is opposed to the view that they are
chromatin or microsomes.
Influence of Warmth of the Soil on the Cell-formation of Plants.*
—RE. Prillieux finds that the effect of warmth in the earth is to cause a
hypertrophy of the interior of the stem in a young plant; when
closely examined, this is found to be accompanied by multiplication
of the cell-nuclei. In the bean and the pumpkin, when the seeds
have germinated in earth of 10° higher temperature than the surround-
ing air, cells are often found containing two or three massed or
isolated nuclei, which may be either equal or unequal in size, and
of various shapes. This multiplication is effected by fission of the
nuclei, which generally contain several nucleoli, up to the number of
four or five, of very different forms and sizes, and sometimes obviously
constricted preparatory to their division. At the time of division, a
boundary wall placed either opposite a large nucleus or between two
closely apposed small ones, divides the nucleus into two halves; these
two halves swell up, and the whole has usually a kidney-like shape.
The process is completed by prolongation of the grooves of the surface
through the dividing wall.
Growth of Starch-grains by Intussusception.t—In replying to.
the attack by Schimper{ on the theory of the growth of starch-
grains by intussusception, C. Naegeli points out that there are three
different conditions of the “micellar” constitution of the cell-wall
(using the term “micella” to distinguish the physical ultimate
elements of a substance from the chemical molecules or atoms) viz. :—
(1) The living condition of the cell-wall, when it is in immediate.
contact with living cell-contents; in this condition the cell-wall is.
more or less strongly coloured by aniline pigments, while the contents
do not take up any of them. (2) The cell-wall is in a naturally dead
state when the living contents separate from it, or when they die
while still remaining in contact with it; in this condition the cell-
wall does not take up any pigment, while the contents become
coloured ; and if the cell-wall was coloured when living, it loses its
colour on passing into the dead state. (38) The swollen condition is
caused by the action of alkalies or acids, by long boiling in water,
or by lying for a sufficient time in cold water ; in this state the cell
wall is again capable of being coloured.
In every stage of its growth the starch-grain is a material system
surrounded by a watery fluid, and saturated with water, the tensions
of which are in a condition of equilibrium. When the grain becomes
dry, crevices are formed, a proof that the equilibrium is by this means
* Kosmos, viii. (1881) pp. 63-4.
+ Bot. Ztg., xxxix. (1881) pp. 633-51, 657-77; also SB. Akad. Wiss.
- Miinchen, xi. (1881) pp. 391-438.
¢ See this Journal, i. (1881) p. 909.
ZOOLOGY AND BOTANY, MICROSCOPY, -ETC. Fé
destroyed ; and the fissures have a radial direction crossing the layers
at right angles, a proof that more water is lost in the tangential than
in the radial direction, and that the total quantity of water deposited
in the tangential direction is greater. When substances which
cause artificial swelling act slowly on the naturally saturated starch-
grain, it increases in volume, radial fissures being again formed, a
proof that during this process more water is deposited in the radial
than in the tangential direction. He argues, on mechanical grounds,
that the tensions found in starch-grains can be accounted for only by
intussusception, and that these tensions can cause the secretion of
the soft nucleus and the soft layers only on the supposition that
intussusception is at the same time taking place.
Collenchyma.*—H. Ambronn has carefully investigated the his-
tory of development and the mechanical properties of collenchyma
in a number of instances, especially in Colocasia esculenta and other
allied aroids, and in Umbelliferze and Piperacez.
With regard to the history of its development, these observations
confirm the statement of Haberlandt that, as in the case of bast, no
uniform origin can be ascribed to the collenchyma, but that it varies
in every possible way. Also that the grouping and arrangement of
the cells is the result, in the first place, of purely mechanical and not
of morphological laws; and that, when definite relationships exist
between the collenchyma and the mestome (in Schwendener’s sense of
the term), these relationships are explained by the history of develop-
ment. hese relationships occur in those plants in which the origin
of the collenchyma and of the mestome is uniform, and in those in
which projecting ridges or angles are produced by the formation of
vascular bundles at the periphery, groups of collenchymatous cells
being developed in them in consequence of their centrifugal tendency.
As regards the structure of the collenchymatous cells, they have
in general a prosenchymatous character. They are moderately long,
often 2 mm. or more, and very frequently manifest subsequent seg-
mentation by delicate division-walls. They are always filled with
sap, but contain little or no chlorophyll. The longitudinal walls of
the cells have usually longitudinal crevice-like pores.
Other collenchymatous cells, on the contrary, have more of a
parenchymatous character, and: have usually been formed by secondary
collenchymatous thickening of parenchymatous cells.
The cell-walls of collenchyma are always coloured a bright blue
by chlor-iodide of zinc, but are not coloured by the action of phloro-
glucin and hydrochloric acid. Their power of swelling in water is
not so strong as has usually been supposed; the cells are seldom
contracted by more than 4 per cent. of their entire length by the
application of desiccating reagents.
The elements of the formative tissue out of which the collenchy-
matous cells are subsequently developed are partly cambial, partly
belonging to other meristematic portions. But very often there is
no special formative tissue; the collenchymatous thickening taking
* Pringsheim’s Jahrb. wiss. Bot., xii. (1881) pp. 473-541 (6 pls.).
72 SUMMARY OF CURRENT RESEARCHES RELATING TO
place only as a secondary result in parenchymatous cortical cells,
But we have not yet sufficient knowledge to divide collenchymatous
tissue on this ground into subsections.
Collenchymatous cells differ in one very essential point from true
bast-cells. While in the latter the limit of elasticity nearly coincides
with absolute firmness, in collenchyma the elasticity is overcome by
a comparatively small strain, the firmness only when the strain is
increased three or fourfold,
Since, therefore, a permanent elongation results from the tension
to which the collenchyma is subjected in the young turgid internodes
and leaf-stalks, but no rupture, it is clear that this tissue can, in con-
sequence of its great absolute firmness, afford the necessary assistance
to the intercalary construction of these organs, without however
interfering with their growth in length. That the growth in length
of the collenchyma itself is a consequence of this tension caused by
the turgidity of the other parts of the tissue, can scarcely be doubted.
But whether the permanent elongation of the collenchymatous parts,
caused by the passing of the limit of elasticity, plays any definite
part in this process, must remain undecided in the present imperfect
state of our knowledge of the processes of growth in the cell-walls.
Epidermis of the Pitchers of Sarracenia and Darlingtonia.*—
Prof. A. Batalin has made a careful anatomical examination of the
pitchers of Sarracenia flava, purpurea, and variolaris, and Darlingtonia
californica. He finds that the lower region of the inner epidermis,
the “detentive surface” of Hooker, has no cuticle; while all the
other cells of the detentive surface have one, and especially the long
stiff hairs. The inner region of the pitcher is of a uniform bright-
green colour within and without; but this is true of the inner surface
only so long as no insects have been captured ; it then becomes brown,
the green colour of the outside remaining. While on the green spots
on the inside of the pitcher the moderately thick and nearly colour-
less outer walls of the epidermal cells are quite smooth, at the brown
spots, where insects have come into contact with them, they have one
or more irregular spots of a much lighter colour. Treatment with
chlor-iodide of zinc causes these spots, but not the rest of the cell-
walls, to turn blue.
This observation leads to the conclusion that the contact of an
insect with the epidermal cells causes a change in the latter, which
consists chiefly in the exeretion, between the cuticle and the cellulose-
wall, of a fluid, the nature of which has not been determined, but
which probably has the property of dissolving albuminoids. It
appears to act both mechanically and chemically upon the cuticle,
forcing it outwards, and finally rupturing and almost entirely destroy-
ing it. A change is at the same time taking place in the cellulose-
wall. It assumes a brown colour, and in addition becomes partially
mucilaginous.
The author also describes a peculiar sieve-like disk between the
epidermis and the glands of Pinguicula vulgaris.
* Acta Hort. Petrop., vii. (1880) pp. 343-60 (1 pl.). See Bot. Centralbl., vii.
(1881) p. 327.
-
a
r
&
cs
ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 73
Laticiferous Vessels.*—D. H. Scott has investigated the struc-
ture and development of the laticiferous vessels, chiefly in Tragopogon
eriospermus ; also in Scorzonera hispanica, Taraxacum officinale, and
Chelidonium majus. The following are the most important results :—
The laticiferous vessels are developed out of rows of cells, the
transverse walls of which have been gradually absorbed, and, when
two vessels lie side by side, the lateral walls also partially. The
resorption usually takes place at an early period; in seedlings during
the first stages of germination; in the secondary cortex shortly after
the cells in question have separated from the cambium.
The connection between distant laticiferous vessels is brought
about in two ways; either by rows of cells that run transversely
coalescing with one another, or by protuberances which unite in their
growth, and which finally form canals similar to those of the Conjugate.
Even before the first septa are absorbed, the cells are characterized
by special contents, of which latex is probably a constituent.
Epidermal System of Roots.j—L. Olivier has made a careful
study of the epidermal tissue in the roots of Vascular Cryptogams,
Gymnosperms, Monocotyledons, and Dicotyledons, dividing the latter
into two classes, those in which- the secondary vascular system
originates early, and those in which it originates late. The following
are the general results :-—
The piliferous layer of the root does not correspond to the
epidermis of the stem, but rather to one of its hypodermal layers. It
is this which gives birth to the “ veil,’ a system of layers of cells
proceeding from the piliferous layer; as it peels off, the subjacent or
epidermoidal layer most generally assumes the anatomical character
of the epidermis, and the same physiological functions.
The secondary tissue of the epidermal system of the root is
either parenchymatous or of a corky nature. The secondary epidermal
parenchyma proceeds from a peripheral layer of the central cylinder;
it attains considerable development in Dicotyledons with early secon-
dary vessels, and in Gymnosperms; there is none in Vascular Cryp-
togams, in the great part of Monocotyledons, nor in Dicotyledons with
late secondary vessels.
In Gymnosperms and in Dicotyledons with deciduous primary
bark, the cork is derived from the pericambial layer. It is composed
of tabular cells, the radial walls of which are very short.
In woody Dicotyledons with late secondary vessels, in Monocoty-
ledons, and in Vascular Cryptogams, the production of cork takes
place in the external zone of the cortical parenchyma; the cork is
here composed of cubical cells.
In any particular species, the zone of the root where the cork
appears depends on the transverse diameter of the organ, and on its
physical surroundings. The diameter being the same, the cork is
generally earlier and more abundant in the aerial than in the under-
_ground roots.
* Scott, D. H., ‘ Zur Entwickelungsgeschichte der gegliederten Milchrohren
der Pflanzen.’ Inaugural Dissertation. 23 pp. Wiirzburg, 1881,
¢ Ann. Sci. Nat. Bot., xi. (1881) pp. 5-129 (8 pls-).
74 SUMMARY OF CURRENT RESEARCHES RELATING TO
Passage from the Root to the Stem,*—R. Gérard concludes
from a careful examination of the facts connected with this subject
that a “collar” does not exist as a geometrical expression. Between
the root and the stem is a region, more or less extensive, where the
elements of the root, advancing to the higher parts of the axis, become
modified, gradually assuming the configuration, place, and importance
which they possess in the stem. The transformation of each of the
elements is independent of that of its neighbours, and may take place
slowly or very rapidly. Hence the collar, considered anatomically
from different points of view, presents the most variable aspects. The
transformation of the epidermal system furnishes no guide to the
limitation of stem and root; the change in the epidermis is one of the
phases of the passage.
Using the term in its widest sense, the collar may commence in
the upper part of the radicle and extend to the fourth internode, rarely
passing the cotyledons, or it may be entirely localized in the radicle ;
it may occupy a part of the organ, and the whole or a part of the
tigellum. Most often the passage is completely effected in the tigel-
lum. The size of the collar is in proportion to the diameter of the
lant.
. No family characters can be drawn from the study of the collar;
its peculiarities are constant only in the species. It is connected
with the accommodation of the plant to its surrounding conditions.
Causes of Eccentric Growthj— Dr. E. Detlefsen has investi-
gated the cause of eccentric growth in thickness of woody stems and
roots in a number of instances, and finds it attributable to the four
following causes :—
1. Branches and axillary roots cause, at the point from which they
spring, a diminution of the tension of the bark, and consequently an
acceleration of the growth in thickness, which is most considerable
where the surface of the lateral organ forms the smallest angle with
that of the mother-organ.
2. Every diminution or increase in the tension of the bark is
perceptible over a large extent in the longitudinal direction of the
bast-fibres.
3. Every lateral pressure which causes curvature of the organs
brings about an increase in the tension of the bark on the side which
becomes convex, a diminution on that which becomes concave.
4, Convex surfaces cause an increase, concave surfaces a decrease,
in the tension of the bark, which affects chiefly the different sides of
curved branches and roots.
These influences may be exercised either in conjunction or sepa-
rately.
Hydrotropism of Roots.{ — The term “hydrotropism” has been
suggested for the tendency displayed by roots, when placed between a
* Ann. Sci. Nat. (Bot.,) xi. (1881) pp. 277-430.
+ Detlefsen, E., ‘ Versuch einer mechanischen Erklirung des excentrischen
Dickenwachsthums verholzter Achsen u. Wurzeln.’ 13 pp. (1 pl.) Weimar, 1881.
+ Bull. Soc. Bot. France, xxviii. (1881) pp. 115-21.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 75
moist and a drier medium, to direct themselves towards the former, to
an extent often sufficient to overbalance geotropism. As the resul’ of
a series of observations, M. Mer contests the view that hydrotropism ‘s
a special instinctive faculty of the root; he attributes the phenomeno
to the retardation of growth consequent on an insufficient supply of
moisture, a condition which may completely prevent the manifestation
of geotropism.
Cause of the Swelling of Root-fibres.*—E. Mer and M. Cornu
have observed that when the roots of growing plants are placed in
coloured fluids, if the solution is too concentrated so as to check
growth, each root-fibre swells near the apex, the swelling being often
accompanied by a more or less decided curvature. M. Cornu attri-
butes this phenomenon to the same cause as the swellings caused by
-phylloxera and by gall-insects, viz. not the special influence of a
particular fluid, but tensions developed locally by any cause, and in
many cases the arrest of development of an organ in course of
elongation ; the production of a fluid may, however, in certain cases
co-operate with this.
Frank’s Diseases of Plants—The completion of this work, to
the publication of the lst part of which we have already alluded,t
furnishes a very complete account of the various diseases and injuries
to which plants are subject. It is divided into five sections, as
follows:—1. The living and dead state of the vegetable cell. 2.
Action of mechanical influences. 3. Diseases caused by influences of
inorganic nature. 4. Diseases caused by other plants. 5. Diseases
caused by animals. .
Under the first head the author describes the phenomenon known
as the “apostrophe” of the chlorophyll-grains. The normal position
of the chlorophyll-grains he states to be in a layer especially next to
those parts of the cell-wall which are not in contact with adjacent
cells—on the outer side, therefore, of epidermal cells, and on walls
that border intercellular spaces; and to this position he applies the
term epistrophe. Certain unfavourable influences, as long-continued
absence of light, wounds, &c., cause the chlorophyll-grains to lose
this position, and group themselves along those cell-walls that are
- in contact with other cells; and this abnormal position he calls
apostrophe.
The production of wens is thus described. The first cause is
always a small wound in the periderm, which sometimes appears to be
a crevice over a lenticel. Between the dried margins of the outer
ruptured cortical layer there then projects a living new formation in
the form of a light-brown cushion, which is either a round tuber or a
long wheal, according to the shape of the wound; a cluster of smaller
tubers often break out in addition from the bottom of the wound.
When this cushion projects to a height of 1 mm. above the wound,
it consists only of cortex and bast, not of wood; it is a hypertrophe
of the cortex, enclosed in a young periderm. The parenchymatous
* Bull. Soc. Bot. France, xxviii. (1881) pp. 124-7.
+ See this Journal, i, (1881) p. 273.
76 SUMMARY OF CURRENT RESEARCHES RELATING TO
tissues of the cortex and bast form the greater part of this cushion.
At its base and in the neighbourhood of the bast of the stem is a hard,
horny tissue, consisting of extremely thick-walled cells, resembling
the bast-fibres, but short, also nearly iso-diametric, also of sclerenchy-
matous cells of great size, their cell-walls so greatly thickened that
the cavity has nearly disappeared, and with pit-canals. At a later
stage the woody tissue is also enclosed in the hypertrophy. Nothing
is said by the author about adventitious buds,
Among parasitic fungi causing diseases of plants, Frank includes
species of Chytridiacer, Saprolegniacee, Peronosporee, Ustilaginer,
Urediner, Hymenomycetes, Discomycetes, and Pyrenomycetes; and
describes the following new species, viz.:—Saprolegnia Schachtii, on
Pellia epiphylla; Ramularia Vicie, on Vicia tenuifolia ; Cercospora
Phyteumatis, on Phyteuma spicatum; and Gleosporium Phegopteridis,
on Phegopteris polypodioides. The mycelium of Agaricus melleus he
regards as the cause of the extensive vine-disease known in France as
“plane des racines.” The sclerotial disease of rape-seed is caused by
Peziza sclerotioides; and that of Impatiens glandulifera and other
species of Balsaminee by a fungus to which Frank gives the provi-
sional name Sclerotium Balsamine. The lowest internodes of the
stem lose their turgidity, become flaccid, and look as if they had been
boiled ; and the plant quickly dies. The tissue is penetrated by a
mycelium on which are small black sclerotia. |
A full account is given of the production of galls by Phytoptus
and other gall-producing insects, The following description is given
of the formation of the bag-shaped galls on the leaves of Prunus
Padus. The insect probably in the first instance inflicts injuries
which excite the production of the galls; but they only retreat into
the galls at a later period when the care for their offspring comes
into play. 'The same appears to be the case with Erineum tiliacewm.
The insect could not be detected either at the spot where the injury
is first made, or in the immature gall; not till the beginning of
June, when they are found in abundance, with their eggs, in the galls.
In the case of the lime the injury appears to act on both sides of the
leaf,
B. CRYPTOGAMIA.
Cryptogamia Vascularia.
Prothallium and Embryo of Azolla.*—Prof. 8. Berggren has
followed out carefully the development of the prothallium and embryo
of Azolla caroliniana.
As in Salvinia the endospore splits, on germination, along its
three edges. On escaping, the prothallium has the form of a slightly
convex disk, consisting in the middle of several layers of cells, at the
margin of only one, and separated below by a thin hyaline membrane
from the large protoplasmic spore-cavity. Shortly afterwards an arche-
gonium is formed near its centre, consisting of four cells enclosing the
oosphere and of four neck-cells. If this archegonium is fertilized, no
* Lunds Univ. Arsskrift., xvi.; and Rey. Sci. Nat., i. (1881) pp. 21-31 (1 pl.).
ee
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. (7
others are usually formed, but if not a few others are subsequently
developed. When quite mature the part of the prothallium which
projects outside the spore is nearly hemispherical, and three obscure
wings are produced by three longitudinal furrows. The cells contain
chlorophyll.
The position of the oosphere with respect to the neck of the
archegonium probably corresponds to that in Salvinia. After fertiliza-
tion itis divided by the first oblique division-wall into a smaller upper
cell facing the neck of the archegonium, and a somewhat larger lower
cell filled with coarsely granular protoplasm. By successive walls
vertical to one another and to the first division-wall, and parallel to
its longitudinal axis, the embryo is then divided into octants. In each
octant a wall next appears parallel to the first division-wall; and the
entire embryo then consists of 16 cells, arranged in four parallel
rows. :
The four cells which lie at the upper pole are the rudiment of the
foot. Of the four lowermost cells one is the origin of the apex of the
stem, another developes into an organ resembling the first leaves, the
two others are together the rudiment of the scutellum. In its sub-
sequent growth the young apex of the stem follows the ordinary laws ;
only the bud is at first straight, and the characteristic curving upward
of the cone of growth is a subsequent phenomenon. The leaves first
produced are strongly concave, and, in contrast to the later ones, are
not lobed. Some of the hairs which mark the upper side of the apex
of the stem are formed at the same time as the first leaf. The scu-
tellum originally encloses the bud as a crescent-shaped growth, the
margins of which gradually approach until it encloses it like a
sheath. The leaf-like organ resulting from the second cell of the
lower pole of the embryo is at first, like the scutellum, independent
of the apex of the stem, and morphologically equivalent to it. Neither
can therefore accurately be termed aleaf. The first vascular bundle
of the plant is formed at an early period by tangential walls in the
eight cells which compose the centre of the embryo.
After fertilization the embryo turns, as in Salvinia, within the
archegonium, so that the apex of the stem is turned towards that of
the prothallium. The embryo breaks through the prothallium near
the archegonium, and the prothallium then surrounds the foot of the
embryo like a cup, carrying the withered archegonium on its dorsal
side behind the scutellum.
To prepare for fertilization, the massule of the microsporangia,
with their anchor-shaped glochidia, fix themselves in large numbers
to the under epispore of the macrospores which are floating on the ~
‘surface of the water. The central fibrous portion of the floating
apparatus is perforated by a narrow canal, through which the anthe-
rozoids probably reach the archegonium. By their subsequent growth
‘the prothallium, and later also the embryo, force themselves into this
canal, and increase its size. By this means the three floating bodies
are displaced from their original position, and finally stand at a right-
angle from the macrospore. The indusium which covers the floating
apparatus in the form of a brown cup is at the same time pushed
78 SUMMARY OF CURRENT RESEARCHES RELATING TO
upwards, and finally forced against the embryo. The hood-like
fibrous layer which is closely applied to the floating apparatus, is
turned over, and surrounds the foot of the embryo like a collar.
Shortly afterwards the embryo detaches itself from the macrospore ;
the margins of the scutellum become broader, and then lie on the
surface of the water in the form of eups or scales.
The strongly refractive bodies previously observed by others
between the indusium and epispore, are, according to the author,
Nostoc-cells, which find their way into the crevices between the scu-
tellum and the young leaves when the apex of the embryo appears
outside the epispore.
Development of the Sporangia and Spores of Isoetes.*—On the
disputed point whether the sporangia of Iscetes spring from super-
ficial or from deeper lying cells, E. Mer considers that he has
demonstrated the latter from the case of sterile leaves which are the
result of the abortion of the sporangia at various stages.
In the earliest stage of development of the sporangium, while the
leaves are still in vernation, it is not connected with the leaf by a
pedicel; the tissue is, on the contrary, homogeneous, composed of
young, very delicate, polyhedral cells, with no trace of trabecule or
envelope. The pedicel is afterwards formed by expansion of the
lateral parts. The cells of which it is composed differ from those of
the rest of the organ ; they are elongated horizontally, are polyhedral,
with very acute angles, and enclose starch. ‘The macrosporangia and
microsporangia can be distinguished even at this period. Among the
cells of the macrosporangium appear radiating rows of cells, similar
to those of the pedicel, which are the young trabecule ; the external
envelope becoming at the same time differentiated.
In the second stage the mother-cells of the macrospores increase
in size, and contain vacuoles, growing at the expense of other cells
which decrease in size and at length entirely disappear. The
nutritive tissue is finally confined to one or two rows of cells situated
at each side of the trabecule, which no longer contain starch,
In the third and final stage the mother-cells of the macrospores
divide into tetrahedra; the macrospores become isolated, and float in
the empty space between the trabecule. The mother-cells of the
microspores cannot be made out till a later period than is the case
with the macrospores.
In the primitive meristem, from which are developed the macro-
and microsporangia, three tissues are speedily differentiated: viz. a
formative tissue destined to produce the mother-cells; a nutritive
nitrogenous tissue, which is absorbed at the expense of the mother-
cells; and an amylaceous nutritive tissue intended to supply the
mother-cells with nutriment.
M. Mer found that the supply of food-material caused a re-
markable difference in the development of Isoetes lacustris, of which
he accordingly distinguishes four forms. An abundant supply of
food is necessary for the formation of the macrosporangia, an
* Bull. Soc. Bot. France, xxxviii. (1881) pp. 72-6, 109-13.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 79
insufficient supply promoting the production of microsporangia.
The dissemination of the macrospores extends over a longer period
than that of the microspores. The bulbils correspond in this respect
to the macrospor-s.
Muscinee.
New Genera of Mosses.*—C. Miller describes four new genera
of mosses :—Wilsoniella, belonging to Bryacez, one species from
Ceylon, and another from Australia; Thiemia, belonging to Funa-
riacex, one species from Burmah; Rehmanniella, belonging to Pot-
tiaceze, one species from South Africa; and Hampeella, belonging to
Hookeriacee, one species from Java.
Classification of Sphagnacese,t—C. G. Limpricht lays consider-
able stress, in the determination of species of Sphagnum, on the
~ relative position of the chlorophyllaceous and the hyaline cells in the
leaves of the branches, a character which he considers has been too
much neglected by Warnstoff in his recent synopsis of the group.}
Limpricht reunites S. subbicolor Hampe and S. glaucum vy. Klinger.
to S. cymbifolium.
Characee.
Cell-nucleus in Chara foetida, §—F. Johow has made an extensive
series of observations on the changes which take place in the nucleus
in cell-division in Chara fetida, for the purpose of determining the
correctness on the one hand of Schmitz’s description of it as “ direct
division of the nucleus,’ || or that by Treub and Strasburger as
“fragmentation.” For this purpose he used chiefly the apical cells
and primary segment-cells of the stem, those of the so-called “ pro-
embryo,” of the leaves and cortical lobes, and of the nodes, employ-
ing the methods of hardening and colouring by means of picric acid
and hematoxylin.
The results obtained were in many respects different from those
previously described by Schmitz, Treub, and Strasburger, a difference
which the author suggests may be explained by the fact that the
various observers have had under observation different species or
varieties of Chara. The “fragmentation” which Strasburger de-
scribes was also not observed by Johow in the staminal hairs of
Tradescantia, the parenchymatous cells of Nicotiana and Tropeolum,
or the suspensor of Orobus. The following are the chief points on
which he insists. .
The cell-nucleus of Chara fotida retains the same structure in
essential points throughout its existence, viz. a homogenous matrix
in which are imbedded chromatin-particles of varying number and
form; the occurrence of the nuclear wall is not limited to any par-
ticular stage. A disorganization of the cell-nucleus did not accom-
* Bot. Centralbl., vii. (1881) pp. 345-9.
¢ Ibid., pp. 311-19.
{ See this Journal, i. (1881) p. 773.
§ Bot. Ztg., xxxix. (1881) pp. 729-43, 745-53 (1 pl.).
|| See this Journal, i. (1881) p. 475. ;
80 SUMMARY OF CURRENT RESEARCHES RELATING TO
pany or follow the fragmentation; on the contrary, the multiplication
of the nuclei was accompanied by a considerable increase in size of
the chromatin-particles and of the matrix. The same was the case
with the cell-nucleus of Phanerogams. The division of the nucleus
in the cell-division of Chara fotida is completed in a manner very
different from the later multiplication of nuclei, and presents also
but little resemblance to the mode of division in most animals and
plants. But in the older nuclei there is a considerable series of tran-
sitional forms in the same plant, to the most simple mode of division
by means of external constriction of the nuclear mass without internal
differentiation.
There appears to be no essential morphological distinction between
karyokinetic division and fragmentation.
Fungi.
Conidial Apparatus in Hydnum.*—Ch. Richon describes what —
he considers to be a hitherto undetected reproductive apparatus
in Hydnum erinaceum. It resembles that described by M. Cornu in
Ptychogaster albus, and consists of intracellular conidia in the paren-
chyma, situated in the superior zone of the receptacle, and prolonged
into the median zone. Instead of being produced at the extremity of
cells of the parenchyma, they are formed and develope in the interior
of the cells. They vary in size from 6-7 p in diameter, being usually
ovoid, less often rod-shaped. Conidia of somewhat similar origin
are found in Fistulina hepatica, Polyporus sulfureus, and Corticium
dubium.
Alternation of Generations in Uredineew.t—E. Rathay confirms
Winter’s observation that the Cwomata, on roses, potentillas, and the
raspberry, are the ecidial forms of Phragmidia ; he found spermogonia
on them. The test of an ecidial form he considers to be not the
envelope or the chain of spores, but the presence of spermogonia.
He regards Melampsora populina and Aicidium Clematidis as
probably developmental forms of the same species.
Mode of Parasitism of Puccinia Malvacearum.t—The mode in
which the germinating filaments from the sporidia of Puccinia Malva-
cearum penetrate the host has been variously stated to be through the
stomata, and through the cuticle where the lateral join the superficial
cell-walls. E. Rathay finds that though the latter is often the case,
they frequently perforate the epidermal cells at a point distant from
any lateral wall.
Sterigmatocystis.§ —Cramer first described this genus of fungi
from S. antacustica, found in the ear of a deaf person. M. Bainier
now gives the characters of six new species:—S. usta, ochracea,
* Bull. Soc. Bot. France, xxviii. (1881) pp. 179-82 (1 pl.).
+ Verhandl. zool.-bot. Ges. Wien, Jan. 5, 1881. See Bot. Centralbl., vii.
(1881) p. 164.
{ Verhandl. zool.-bot. Ges. Wien, Dec. 1, 1880, See Bot. Centralbl., vii.
(1881) p. 163. sae
§ Bull. Soc. Bot. France, xxviii, (1881) pp. 76-9.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 81
quercina, aerea, Helva, and fuliginosa. They are found on all sorts of
ternary compounds, starch, dextrine, sugar, paper, tannin, &c., and
may be cultivated on gelatine, gluten, and bread, but not apparently
on meat. They are extremely abundant on grapes, and on other
edible commodities, the species being especially S. nigra, carbonaria,
and fuliginosa, while S. glauca is found in wine. Glycerin is ex-
tremely prejudicial to their growth, and may be used to prevent
their appearance. The spores have a great power of resistance to
cold; and, when once established, these moulds are very difficult to
extirpate.
Oospores of Phytophthora infestans.*—M. Cornu has reinvesti-
gated the vexed question of the oospores of Phytophthora (Pero-
nospora) infestans, which have not yet been recognized with certainty.
The bodies described by W. G. Smith as the sexual spores of the
_ Phytophthora, Cornu agrees with de Bary in regarding as in reality
the oospores of a Pythium. Caspary and Berkeley, on the other hand,
regarded as the true oospores of Phytophthora the bodies described by
Montagne under the name Artotrogus hydnosporus, a conclusion
doubted by de Bary on the ground of their alleged identity with
similar bodies found on the turnip. Cornu shows, however, that this
latter parasite is altogether different from that of the turnip. The
bodies described as Artotrogus are of two kinds, one echinated, the
other not. The former of these Cornu considers in all probability to —
be the oospores either of Phytophthora, or of some Saprolegnia at
present unknown.
Peronospora viticola.j—E. Prillieux, after pointing out the
known existence of conidia or summer-spores, and oospores or winter-
spores, states that he has been able to convince himself, during the
course of a mission undertaken under the instructions of the Minister
of Agriculture, that there is no doubt as to the “ prodigiously
abundant formation of winter-spores” in various parts of Trance.
The quantity of these small bodies which may be found in one dry
leaf appears to be enormous (200 per square millimetre). Not
much harm is done in dry weather, but when the seasons are wet
me author thinks that all the vine-leaves should be collected and
urnt.
Vegetation of Fungi in Oil.t—P. Van Tieghem some years since
observed the development of flakes of mycelium in a bottle of olive
oil; this was due to two germs; one not cultivable on slices of
potato, the other identified as very nearly allied to Verticilliwm cin-
nabarinum. Immersion of seeds or pieces of the higher plants,
covered with mycelium growth, in the same medium, and placing in
an atmosphere at about 25° C., produced after a few days a plentiful
growth of mycelium over these bodies, on the surface of the oil, and
at any points at which spores had been left in contact with the air.
It is established that the oil is absolutely necessary to the life of the.
* Bull. Soc. Bot. France, xxviii. (1881) pp. 102-9.
+ Comptes Rendus, xciii. (1881) pp. 752-3.
t Bull. Soc, Bot. France, xxvii. (1880) p. 353.
Ser. 2.—Vot, II. G
82 SUMMARY OF CURRENT RESEARCHES RELATING TO
fungus; it will not develope in linseed oil, colza oil, or water, and
is killed if transferred from olive oil to any of these liquids. If the
mycelium is removed from the plants before being transferred to the
oil, its development is very slow, and fructification is not obtained;
this is probably due to the want of the water which the plant
contained. The systematic position of the form could not be
determined.
He also finds as the result of subsequent investigations* that a number
of mycelia flourish in a variety of oils, as those of olive, poppy, linseed,
and colza, and in castor-oil. Most of these are still undetermined,
and one appears to be a species of Verticillium. Among those which
appeared in olive-oil is a new Saccharomyces, to which he gives the
name S. olei. It consists of oval cells arranged in branched threads,
which occasionally become broken up, and the isolated cells then bud
and form new threads. The average size of the cells is 4:0 pw by
2°51; their contents of a pale or, in refracted light, of a slight rose
colour. No disengagement of gas, or special odour, accompanies their
growth. At length they form a farinaceous deposit at the bottom of
the water. The nature of the oil is completely changed in the
process, becoming white and milky in the course of about eight days.
Neither S. cerevisie nor any other allied species will grow in
olive-oil.
A moneron grown in the same way in castor-oil developed through
the whole substance of the oil, rendering it opaline; it does not,
however, change its nature or saponify.
If into any oil that has not been purified any body is introduced
which has been soaked in water, the surface of the body is seen, after
a few days, to be covered with an abundant vegetation, composed of
the mycelia of a number of fungi, among which have been detected
Mucor spinosus and pleurocystis, and species of Verticillium, Cheeto-
mium, and Sterigmatocystis, but most abundantly of all, Penicillium
glaucum, which fructifies profusely, not only on the surface, as is the
case with aqueous solutions, but throughout the oil. Other Asco-
mycetes produce not only their conidia, but also their perithecia in
these conditions. These fungi are produced ina great variety of un-
purified oils, but not in an oil which has been purified by sulphuric
acid like colza-oil, or which has been strongly heated, like linseed-
oil. If the moist substance is placed for a time in boiling water
before its immersion in the oil, it still becomes covered after a time
with the fungoid growth, showing that the spores are in the oil and
not in the moist substance ; the reason for their not developing in the
oil, if left to itself, being that water is necessary for their growth.
The plant obtains its necessary oxygen and nitrogen from the air dis-
solved in the oil; the oil itself furnishing direct to the plant the
carbon and the hydrogen. A sufficient quantity of nitrogenous and
mineral substances is always contained in unpurified oil. The oil
remains perfectly limpid, and apparently does not undergo any change
in composition, except a crystallization of fatty acids, indicating a slow
saponification.
* Bull, Soc. Bot. France, xxviii. (1881) pp. 70-1, 137-42.
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 83
Parasitic Fungi.*—M. Cornu notices the occurrence of two para-
sitic fungi on hosts not previously observed, Cylindrospora nivea on
Veronica arvensis, and a uredo, probably belonging to the cycle of
generation of Acidium nitens, on an unnamed American Rubus.
Ear-Fungi.t—Fr. Betzold has detected the following species of
Hyphomycetes as accompaniments of diseases of the ear, viz. Asper-
gillus nigricans, flavescens, and fumigatus, and Trichothecium roseum.
He does not regard these fungi as saprophytes, but as the actual cause
of inflammation.
Insect-destroying Cryptogam.j—-J. Lichtenstein calls attention
to a very curious case of parasitism, namely, the presence in the hot-
houses of the Jardin des Plantes, at Montpellier, of an “insecticide
eryptogam ” (a Botrytis), which killed all the aphides on a
Cineraria.
The action of the parasite would appear to cease in the open air,
at least the author was unable to inoculate with it either the
Phylloxera or an Aphis (Chaitophorus aceris). Perhaps, the author
speculates, direct inoculation is impracticable, and there may exist an
intermediate stage on other creatures, as in Hntomophthora and cine
Cryptogams.
Brefeld’s Schimmelpilze.§—The fourth part of O. Brefeld’s general
work on mycology treats of the moulds or Schimmelpilze, and is
introduced by some general remarks on the cultivation of microscopic
fungi. He especially recommends the use of Geissler’s modification
of Recklinghausen’s chamber, which has special advantages for the
culture of single specimens.
The life-history of Bacillus subtilis is described in detail, followed
by that of Chetocladium Fresenianum, parasitic upon Mucor and
Rhizopus, but which will readily grow in nutrient fluids, and can
easily be made to produce zygospores. Two new species of
Thamnidium, and one of Mucor, are also described. He regards as
_ the ancestor of the Zygomycetes a form with one kind of sporangium,
from which sprang the Thamnidiez with sporangia and sporangioles.
Thence were derived various branches:—by the reversion of the
sporangioles to forms with single conidia; by the separation of the
sporangioles and conidia to separate receptacles, to the Choanephoree ;
by the abortion of the sporangia to the Cheetocladiacez.
Under the head of Pilobolus, a special description is given of
P. anomalus, in which large portions of the mycelium, divided off by
septa, produce each a receptacle ; a division in the young sporangium
after the formation of the columella leads to the production of the
sporiferous portion and the swelling-layer, which, after first becoming
dry, then absorbs water, swells up, and separates the sporangium from
the pedicel. The author has, in this species, observed germinating
* Bull. Soc. Bot. France, xxviii. (1881) pp. 143-6.
+ ‘Zur Aetiologie der Infectionskrankheiten,’ 1880, pp. 95-109.
{ Comptes Rendus, xelii. (1881).
§ Brefeld, O., ‘Unters. aus dem Gesammtgebiet der Mykologie. Heft 4.
Bot. Unters. iiber Schimmelpilze.” 191 pp. (0 pls.). Leipzig, 1881.
Gg 2
84 SUMMARY OF CURRENT RESEARCHES RELATING TO
zygospores in the ordinary receptacles. Very different is the origin
of the receptacle in five other species of Pilobolus, in which only a
single short tuberous piece is divided off from the mycelium by a
septum, the receptacle being produced entirely in this. The energy
of the process by which the spores are thrown out is in inverse pro-
portion to the length of the pedicel. The author was unable to find
zygospores in these species, and believes the sexual mode of repro-
duction to have fallen, with them, partially into abeyance. The
production of the receptacle of Pilobolus is greatly dependent on
light.
Descriptions follow of other Zygomycetes, Sporodinia grandis and
Mortierella Rostafinskii, the latter of which is found on horse-dung.
The short mucor-like receptacles are formed on short stolons, and are
usually fixed to the substratum by thick bundles of rhizoids at the
base of the receptacle, often enveloping it, and thus forming a tissue
composed of unseptated filaments, resembling a capsule, and about
one-fourth the height of the receptacle, the sporangium being exserted
from itsapex. The outer portions of this structure are of a yellowish
or brownish colour, and are cuticularized, the sporangia remaining
white even when mature. The sporangia are not produced from the
entire apex of the fertile hyphz, but only from a small central zone, a
peculiar constriction being formed beneath them. When the spores
have been formed out of the protoplasm, a division-wall separates the
sporangium from the pedicel without the formation of a columella.
As the spores are developing, the walls of the upper part of the
pedicel become thicker, as also does the basal part of the wall of the
sporangium, which remains behind like a collar when the upper part
has become separated and the spores have escaped. In old cultures,
or those which have been disturbed, gemmz often made their appear-
ance, as in Mucor racemosus. In very poor nutrient fluids, the number
of spores was reduced from many thousands to two or four, and the
rhizoids were entirely wanting. After long-continued culture, and
the succession of from ten to twelve generations, the production of
non-sexual receptacles almost entirely ceased, and zygospores only
were produced, enclosed in large brown capsular tissues. In other
instances, however, this envelope was wanting.
The nature of the sporangium and the conidia derived from it are
used by Brefeld as the foundation of the classification of the Zygo-
mycetes, which he divides into five families, viz. Mucorinex,
Thamnidiez, Choanephorex, Cheetocladiacexe, and Piptocephalidez.
In Entomophthora radicans, Brefeld describes the formation of the
resting-spores, from which he concludes that the Entomophthorez
form a small family more nearly allied to the Ustilaginee than to the
Peronosporex, being most nearly connected with the former through
Entyloma. In both families he considers the resting-spores to be
oogonia, in which the formation of spores is suppressed, and the
oogonium itself has become a spore. Their natural position is
therefore in the Oomycetes, near to the Phycomycetes. Two new
species of Empusa are described, one parasitic on flies, the other on
,. gnats.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 85
The formation of both conidia and sclerotia is followed out with
care in Peziza tuberosa and sclerotiorum, and the view is confirmed
that there is no causal connection between the two. The sclerotia
always proceed from a mass of hyphze which put out abundance of
shoots, and are more slender than other mycelial filaments. As soon
as they begin to coil and interweave, a general lateral branching takes
place, which gradually fills up all the air-cavities in the ball, and
unites the hyphz with one another. The sclerotia retain their power
of germination for years, if kept dry. They then put out thick
greyish-yellow club-shaped bodies composed of nothing but hyphe,
which grow by apical growth and finally become the fertile cups, the
apical growth ceasing at the middle, while the peripheral filaments
continue to grow and branch abundantly. After growth in length has
ceased, a layer of paraphyses is formed gradually from the middle
towards the margin, the asci being then formed, their formation con-
tinuing after the expulsion of the first spores. The ascospores, eight
of which are contained in each ascus, are 8 » broad and 12 p long.
They germinate at once, and form ordinary mycelia with sclerotia.
In the autumn the club-shaped bodies often form secondary clubs,
even to several generations, which produce cups in the next spring.
If the clubs are covered with a small quantity of earth, they produce
much-branched strings of Rhizomorpha, on which new clubs appear
at all points. In certain circumstances the branches of the paraphyses
develope into receptacles with conidia ; they often make their appear-
ance in the cups as forerunners of the ascogenous layer.
On the sclerotia of these two species of Peziza there often appears
a pyenidial form which interferes with the formation of the cups.
Cultivation produced no other form of this fungus, which Brefeld
calls Pycnis sclerotivora. The germination and formation of the
mycelium and abstriction of the spores are described in detail.
With regard to other Ascomycetes, he finds the processes similar
in all essential points in Peziza cibarioides, Fuckeliana, coccinea, and
-— aurantia, Otidea leporina, Sarcosphera macrocalyx, Leotia lubrica, Geo-
glossum, Morchella, and Helvella; except that in the last two genera no
conidia were observed, and in Peziza Fuckeliana the attempt was
unsuccessful to obtain from the Botrytis-spores perfect sclerotia which
developed into cups. All the above-named agree in this point, that
the differentiation of the hyphe into sterile and fertile takes place
only when the receptacle has nearly reached maturity. In other
forms, as Ascobolus denudatus, Erysiphe, Eurotium, Penicillium,
Melanospora, and Xylaria, this differentiation takes place at a very
early period. In the first of these, after several generations, large
masses of thallus arose out of scolecites. In some instances the for-
mation of conidiophores precedes or accompanies that of the recep-
tacles; but they may be altogether wanting. Brefeld considers the
so-called “pollinodia” to have no other function but that of
enveloping tubes; the conidia and receptacles are therefore of non-
sexual origin.
In three small Ascomycetes grown on hare’s dung, one of which
resembled Ryparobius myriosporus, the formation of the asci could be
86 SUMMARY OF CURRENT RESEARCHES RELATING TO
traced back to a single cell or ascogenous filament, as also was
the case in Melanospora, the perithecial form of Botrytis Bassiana.
As regards the general structure and position of the Ascomycetes,
Brefeld regards the three following as the most important points :—
1. The degradation of the various forms of fructification; 2. The
disappearance of sexuality, either from the forms of fructification or
with them; 3. The reversion of sporangia to conidia. All known
fungi he divides into the two great divisions of Phycomycetes and
Mycomycetes. To the Phycomycetes belong two classes, viz. :—
1. Zygomycetes (Mucorinew, Thamnidiew, Choanephoree, Cheto-
cladiacee, and Piptocephalidee); and 2. Oomycetes (Chytridiaces,
Saprolegniex, Peronosporee, Entomophthoree, and Ustilagines).
The Mycomycetes are composed of three classes, viz. :—3. Asco-
mycetes; 4. Aicidiomycetes; and 5. Basidiomycetes. The lowest
forms of fungi he regards as nearly related diverging branches from
a common origin. The same is the case also with the higher forms.
In both higher and lower forms he finds the same tendency for the
sporangia to revert to the condition of simple conidia, and for the
fructification to lose its sexuality.
The multinucleated condition of the cells of many unicellular
Thallophytes Brefeld regards as an indication that they are descended
from multicellular forms from which the cell-walls have disappeared.
The family in which this degradation has been carried to the greatest
extent is the Myxomycetes, constituting a third great division of
the Fungi, in which the cell-walls even of the spores have
disappeared, the vegetative life being carried on by permanently
naked cells. ,
Both the higher and lower Fungi may be traced back to a
sporangiferous parent-form, probably green and belonging to the
Alge, in which there was already a differentiation into sexual and
non-sexual forms of fructification. Sexuality was therefore the
original condition of all Fungi, but has in many cases disappeared, a
phenomenon not seen elsewhere in the vegetable kingdom. All three
forms of fructification, or only some, or none, may have degenerated
to the condition of conidia, Hence we may get forms with only male,
others with only female organs. The number of forms of fructification
may also be increased beyond three, as in the Mcidiomycetes. There
may also be in addition a pure vegetative mode of increase, by the
breaking up of the mycelium, or the separation of shoots. In these
cases all other modes of reproduction, all kinds of fructification,
may disappear, and propagation take place in a vegetative way only.
The pollinodia of the Ascomycetes not having the male character
assigned to them by de Bary, Brefeld regards the ascocarp as an
originally female mode of fructification which has lost its sexual
character ; the spermatia indicating, in their inability to germinate,
their original male character. The conidia are the result of degrada-
tion of the asci. In the Erysiphew, Pyrenomycetes, and Disco-
mycetes, the apothecia or perithecia may, from analogy, be regarded as
similar degraded female organs; in the ascophores of Hxoascus and
Taphrina both sexual and non-sexual forms of fructification occur.
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 87
If the ascus is to be regarded as a sporangium, and the conidia as
degraded asci, it is clear that no great stress should be laid, from a
systematic point of view, on the higher differentiation of the fructifi-
cation, its development into a carpospore, &c. A relationship of the
Ascomycetes may then be traced downwards with the Phycomycetes,
upwards with the Aicidiomycetes and Basidiomycetes. In the ascus
or sporangium is the point of connection with the lower Fungi, in the
conidia or degraded sporangia that with the higher Fungi; while
the sporangium further indicates the descent of all the Fungi from
Algee.
Influence of Light on the Growth of Penicillium,*—lIn his experi-
ments on the growth of Fungi in oil,j P. Van Tieghem observed that
the development of Penicillium glaucum is powerfully affected by
light. It is only in the spots that are strongly illuminated that
' the mycelium developes into a continuous coating, very little or none
appearing on those that remain dark.
Production of Microphytes within the Egg.t—G. Cattaneo has
lately occupied himself with the solution of the question whether the
fungi which so frequently develope within bird’s eggs are introduced
into the egg from without or whether, as is held by a number of Italian
investigators to be the case with regard to the Schizomycetes, they
may arise independently within the egg, out of its own constituent
elements. A preliminary consideration of the ways by which the
spores might enter the egg while still in the body—namely, by the
lungs and air-sacs, by the alimentary canal, and finally by the cloaca
and oviducts—leads the author to the conclusion that it is most
unlikely that the spores should enter the developing egg by these
routes. Thus the development of fungi in eggs shortly after they
are laid is probably not to be referred to spores introduced from with-
out, even though the fungi should sometimes enter through the egg-
shell. His own observations on the development of fungi within and
upon eggs, which were carried on in a moist chamber, in part upon
eggs covered with a coat of wax or copal varnish, led to the result that
the growths of Penicillium, Aspergillus, &c., which often develope in
such abundance on eggs thus treated, seldom pass into the interior, and
have not the power of penetrating the skin of the shell; and that, on
the other hand, the growths of Leptothria and Leptomitus which spring
up only in eggs which have not become decomposed, are produced on
the inner side of the skin of the shell, and manifest centrifugal growth
outwards through the pore-canals of the egg-shell, without showing
any indication of an entrance from outside.
Etiology of Diphtheria§—Oertel believes the contagium of
' diphtheria to be an excessively minute organism, to which he gives the
name Micrococcus diphtherie. It has an oval form, with a length of
* Bull. Soc. Bot. France, xxviii. (1881) p. 186.
+ See ante, p. 81.
{ Atti Soc. Ital. Sci. Nat., xx. (1 pl.). Cf. Zool. Jahresber. Naples, i. (for
1879) p. 123.
§ ‘Zur Aetiologie der Infectionskrankheiten’ (1881) pp. 199-246. See Bot.
Centralbl., vii. (1881) p. 269.
88 SUMMARY OF CURRENT RESEARCHES RELATING TO
1-1'5 p, and a breadth of 0:3 w; larger individuals, found nearer
the surface, being 4°2 » longand 1:1, broad. Where the individuals
are more scattered, they occur mostly in pairs, rarely a number con-
nected into a torula-like chain. When present in masses the cells le
so close together that it is difficult to determine whether they
are connected or not. They are then imbedded in a gelatinous
envelope, and thus combined in masses into a colony. Addition of
acetic acid makes the mass clearer, so that the combination in pairs
and the more rod-like form of the separate cells is more readily seen.
These organisms penetrate the epithelium. They are found chiefly
in the mouth and throat; and may be conveyed through the air,
by direct contact, through the saliva, or by contact with a great
variety of objects, as plates or drinking glasses, clothes, toys, linen,
&e. The most favourable nidus for their development and fatal
activity is when, from injury to the cuticle, they come into direct
contact with the blood and tissues.
The author believes the micrococcus to be specifically distinct
from those which produce other infectious diseases. The apparent
spontaneous production in some cases of diphtherial disease may arise
from the germs being present in some other organism in a different
form, in which it is incapable of producing disease, or from its being
present in the infected subject in a latent condition, waiting favourable
conditions for its development. The average length of time through
which the disease runs before reaching its culmination may be stated
as from two to five days.
Properties and Functions of Bacteria.*—Prof. J. B. Schnetzler
finds that Bacteria, as well as Infusoria of the genus Vorticella, live
and exhibit activity in a solution of curare; moreover the muscles
and cilia of the Turbellarian Planaria torva and some of the muscles
of Gammarus pulex were found to act with energy after being exposed
to the same reagent for twenty-four hours. But Bacillus subtilis is killed
immediately by perchloride of iron solution. The bacteria produced
during decomposition of a plant do not produce fatal results when
injected into the vessels of a rabbit. Prof. Schnetzler shows that a
highly organized plant may be watered exclusively by a fetid liquid
full of bacteria, without undergoing fermentation or decomposition
of its parts; the bacteria (Micrococcus and Bacillus) may be found
in the leaves, but they also occur in those of plants which have been
watered with ordinary water. -
Finding bacteria in the condensed moisture which appears on the
cover of a vessel containing bacteria and green algz, Prof. Schnetzler
explains their appearance there by the bursting of the bubbles of
oxygen which rise to the surface under the influence of sunlight and
in bursting scatter the bacteria which they have brought up with
them.
Atmospheric Bacteria.t—Continuing his previous investigations,
on this subject,; P. Miquel gives the averages since obtained by him,
* Bull. Soc. Vaudoise Sci. Nat., xvii. (1881) pp. 625-32.
+ Bull. Soc. Bot. France, xxviii. (1881); Rev Bibl. p. 11.
t See this Journal, iii. (1880) p. 837.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 89
showing for each month the quantity of spores in the air of Mont-
souris, and describes some interesting facts concerning the cultivation
of bacteria.
Bacillus wrece, cultivated in neutral bouillon, fails to the bottom
of the vessel, and dies, leaving the liquid perfectly transparent; but
if a little pure urea is added when the parasite is living, the fluid
becomes cloudy and charged with carbonate of ammonia. Of all the
species cultivated by the author in a state of purity, none abandoned
their special aptitudes nor departed from the cycle of evolution
proper to each. Certain illusions and analogies are therefore to be
guarded against. Bacilli, in the absence of oxygen, can assume a
resemblance to Bacteria, and Bacteria when dead are easily confounded
with Micrococet.
Pathogenous Bacillus in Drinking Water.*—J. Brautlecht has
detected in drinking water, which was considered to be the partial
cause of an epidemic of typhus, a bacillus which he cultivated in a
solution of 3 per mil. gelatine in spring water, with 25 per cent.
ammonium phosphate. This was distinguished from other non-
pathogenous bacilli by the absence of any powerful reducing action
and also of the offensive odour of some other species; having a
pleasant odour somewhat like that of boiled milk. This bacillus
forms filaments in the nutrient fluid, which soon break up into short
rods, which separate into cocci loosely connected in a moniliform
manner. In later cultures only rods and cocci were visible, which
did not exhibit any spontaneous motion. Besides the suspected
drinking water, a bacillus with the same characteristics was found in
the urine of typhus patients, also on the surface of thick masses
of putrefying alge. When inserted beneath the skin of a rabbit,
these bacilli caused violent fever in from 18 to 36 hours.
Connection of Diseases with specific Bacilliij—H. Buchner
describes a series of experiments for the purpose of determining
whether contagious diseases are caused entirely by the bacilli which
are found to accompany them, or whether the action of these is
assisted by a peculiar chemical substance resulting from the diseased
tissue. The results pointed entirely in the direction of the first of
these hypotheses. It was found in the first place that the cattle
disease was produced by bacilli originally taken from diseased
subjects, even when these had been cultivated to thirty-six genera-
tions, when it was impossible for the least trace of any disease-producing
substance to exist which had come directly from the diseased subject.
In the second place, it was found, after repeated and long-continued
culture, that these disease-producing bacilli differed in no visible
respect from the bacilli produced spontaneously in hay; while with
the latter he was able to produce the disease by injecting it into the
blood of white mice and rabbits.
* Virchow’s Arch. path. Anat., Ixxxiv. p.80. See Naturforscher, xiy. (1881)
p- 320.
+ ‘Zur Aetiologie der Infectionskrankheiten,’ 1881, pp. 69-94. See Bot.
Centralbl., vii. (1881) p. 237.
90 SUMMARY OF OCURRENT RESEARCHES RELATING TO
Origin of the lowest Organisms.*—F. Krasan, in an extraor-
dinary production published in the Transactions of a learned Society
as a serious paper, discusses the hypothesis of a possible archibiosis
in the case of the lowest organisms, and supports his opinion in
favour of this mode of origin in at any rate a spirited manner by the
results of a series of experiments. He does not contest the argu-
ment that many of the lowest forms arise from such germs as may
be contained in dust, but insists that the proof of such an origin
is much hindered by the mechanical difficulties of manipulation.
The experiments are divided into three series :—
1. Relations of Bacteria to certain microscopic structures con-
tained in the seeds of many plants, and the action of phosphate of
hydrogen, soda, and ammonia (microcosmic salt) and atmospheric
dust :—
The close connection alleged to exist between bacterian move-
ments and the molecular movements of organic particles is illus-
trated by the phenomena exhibited by drops of oil derived from
seeds, such as those of the parsnep and of melons and gourds, also
hazel-nut kernels, broken up in water (either distilled, stream, or
spring water). These drops are of different sizes, and generally
contain vacuoles filled with water, coloured pale red, and each sur-
rounded by a bluish-green halo, the whole mass being greenish-grey
or pale green; they consist of a mixture of oil, albumen, and a
carbohydrate. If one of the superficial vacuoles is closely examined,
it is seen to contain an immense number of very minute roundish
bodies in rapid movement of a swarming character. The vacuole
increases in size by pushing its way to the exterior, where it finally
bursts, discharging its contents into the surrounding water; a small
portion remains, and is enclosed by the collapsed oil-globule. The
minute bodies thus liberated move towards the edge of the cover-
glass, and at the same time approach each other in pairs, and after
rotating very rapidly become quiescent and unite, forming cylin-
drical masses. These are considered by the writer to be half-formed
bacteria, and they are said to be almost identical in appearance with
true bacteria, but differ in possessing the property of dichroism,
which becomes more marked towards the edge of the glass, and is
probably, together with the phenomena of conjunction, connected
with the proximity of the air. These bodies may be dried, and yet
resume their characters when again moistened.
The following differential experiments were undertaken. To
equal parts of a 55 to 6 per cent. solution of sugar in distilled water
was added a rather smaller proportion of gypsum or freshly
burned coal-ash (rich in sulphate of lime); to one-half of the
mixture was added 20-40 milligrams of atmospheric dust, to the other
half 4-8 milligrams of the phosphate salt; both were stirred, covered,
and set aside in a temperature of 10°-14° C. In 48 hours the dust-
containing mixture contained isolated bacteria in active movement,
while the other showed quantities of them, forming groups on the air-
bubbles; thus a small amount of the phosphate salt was more pro-
* Verh, zool.-bot. Ges, Wien, xxx. (1881) pp. 267-327 (1 pl.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 91
ductive of bacteria than five times its proportion of atmospheric dust ;
in the latter case the forms are chiefly Bacterium lineola, in the
former B. termo; this difference bespeaks a different origin for the
two growths.
Solution of sugar and the microcosmie salt and coal-ashes in dis-
tilled water produced no bacteria in 28 hours after addition of dust,
and but few when left to itself, but with a drop of bacterian liquid it
contained abundance, arranged in tracts; in 455 hours the condition
was essentially the same, but after 68 hours the dust preparation
contained an abundance in masses; also the uninfected solution, but
here development appears to have begun four or five hours later than
in the dust preparation.
Pieces of an almond more than two years old were boiled fora
minute in distilled water, and the decoction put while hot into 9 watch-
glasses, “cleaned, as usual, as well as possible,” and covered up. The
contents of these glasses were variously treated, with the following
results :—
No.1. Left untouched ; developed a yeast-fungus and: some mycelia,
after the lapse of 22 days.
No. 2. Similarly treated; was filled with mould and fermentation
fungi after 13 days.
Nos. 3, 4, and 5, having received, the one 2 grams, the other a
drop of distilled water, the third a drop of emulsion of almond kernel
in distilled water, were clouded with a minute bacterium in 48 hours.
No. 6 received two pieces of almond, and began to be clouded
with a bacillus in 70 hours.
No. 7, infected from an emulsion full of bacteria, swarmed with
the same form in 24 hours.
No. 8, which had received a few milligrams of atmospheric dust,
showed some larger bacteria, some being united into rods and chains,
after 44 hours.
No. 9 was infected with a dried-up drop of bacterium liquid, and
became cloudy in 40 hours.
From these and similar experiments Krasan concludes, first,
that heat disorganizes the molecules of organic substances so as to
render them incapable of becoming rearranged into organic structures
without the stimulus of fresh air or other agents; secondly, this
stimulus need not proceed directly from organic germs strictly so
called, but may just as well be derived from the fresh air itself.
Water and various liquid and solid organic substances are employed,
which are either unaltered by heat, or else have been long in contact
with fresh air.
Krasan considers the possible inorganic origin of low organisms
absolutely proved by his finding them developed first in the Micro-
coccus-, then the Zooglea-form in a precipitate of calcium phos-
phate in calcium sulphate solution to which sugar had been added;
he has observed them to arise from minute granules which occur in
the freshly formed precipitate, and considers it due to decomposition
of the sugar molecules and recombination of their radicals with the
other constituents.
92 SUMMARY OF CURRENT RESEARCHES RELATING TO
2. Development of Monads.—Under this term are here included
only low organisms of the form of swarm-spores, about 4 micro-
millimetres in diameter. These become very slow in their move-
ments, and proceed to reproduce by fission in very concentrated
emulsions, but when transplanted to a dilute liquid become very
active, and exhibit the peculiarity of attracting particles of various
sizes and expelling them again with vigour, a process set down to an
electric energy, residing in its greatest power at the base of the
flagellum. Investigations extending over two years failed in dis-
covering another mode of increase but that by fission. Repeated experi-
ments, however, of which the object—viz. that of discovering a
method of genesis which dispenses with any antecedent organism
is not concealed, were, so the author relates, at length rewarded.
Some “ aleuron-granules” from hazel-nut kernels mashed-up in
water, were observed to resolve themselves into granular jelly-masses
of globular form; from this mass the monad is said to de-
velope, or several may arise from a single mass. A large monad with
a proboscis was seen to arise from an aleuron-granule by fission of its
substance and extension of the gelatinous material at two opposite
points, forming a fusiform body ; if the formative mass is larger than
the normal monad it divides and forms two. Oily drops of pro-
toplasm also become converted into monads. The production of
these organisms is dependent on the time during which the seed has
been left to dry in its shell. Monads were also produced from a
mixture of sugar and stream or spring water and a phosphate, by con-
traction or fission of the flocculent precipitate contained in it. ‘T'wo
sizes of monads are produced from a solution of Umbelliferous seeds
in spring water; the larger are derived from the smaller. Ciliated
Infusoria are said to have been seen to develope from zooglcea-
masses; the process occurs in the early morning, between | and 4 a.m. (!)
Leucophrys is generated with especial ease from water, sugar, and a
phosphate. Thundery evenings in August and September are the
best times for such developments to occur; monads and ciliated
Infusoria are mutually exclusive, and do not develop from the same
solution.
3. Effects of Contact are the subject of the third and last series of
investigations. Krasan finds that the development of bacillus in
infusions of seeds in boiling water is almost entirely dependent on
the retention in the fluid of the solid bodies used to make the
infusion ; but that the presence of ali kinds of solid bodies in infusions
of other kinds considerably facilitates and is indispensable to their
development; the result of this is thus stated. (1) Solid particles
and heterogeneous bodies in a solution of formative organic sub-
stances exercise a favourable influence on the process of formation by
their presence, and being in contact with the solution, inasmuch as
they accelerate the interchange of matter, and give a definite direction
to the organizing activity of the molecular forces. (2) The nature
of the foreign bodies is not without influence on the size, form, con-
sistence, colour, and mobility of the organisms which are produced.
The author invokes the action of physico-chemical forces in
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 93
aid of his theory, and explains the phenomena on which he based it;
chiefly appealing to the different electrical polarities of the substances
employed—a line of argument familiar to most of those who have
studied the question of the origin of life.
It is to be observed, in estimating the scientific value of these
experiments, that the highest magnifying power mentioned as being
employed is 610 diameters, and that as a rule no special attention
appears to be given to the cleaning of the vessels, or the sterilizing
of the air or water, the latter being as often ordinary spring- or
stream-water as distilled. The value of the reasoning is still further
impaired by the fact that the latest experiments which have been
adduced in opposition to the ancient theory here advocated afresh are
dismissed without much consideration, even those of Tyndall receiving
but scanty attention.
Prolongation of Vegetative Activity of Chlorophyllian Cells
under the influence of a parasite.*—According to the Schwendenerian
theory lichens are complex organisms, consisting of an alga, and a
fungus which is parasitic on it. It seems extraordinary that the alga,
thus embraced by a parasite, not only continues to live, but increases
and multiplies, and is apparently endowed with new vigour. The
same alga, alone, becomes discoloured and disappears on the return of
the dry season ; but in the lichen state it often persists for years. - It
has been said by Rees, that there are no other such cases known of
vegetative activity being prolonged under the influence of a parasite ;
but Max Cornu has lately called attention to several. Thus, maples
are often attacked, late in summer, by an Hrysiphus which occupies
the under surface of the leaves. The parts thus occupied remain
green when the rest of the leaf has withered, and even after the leaf
has fallen. Similarly with a parasite which attacks leaves and fruits
of pears, apples, &c. ; indeed, the fact is very general ; the chlorophyll-
cells attacked retain their green and their vital activity longer than
the others. The phenomenon is explained by the fungus counter-
balancing the return of nutritive matters towards the reserve centres.
Green alge have a vegetative period, during which they retain this
colour very intensely; then they grow yellow and form durable
Spores, after which the vegetative part dies. In lichens the fungus
prevents this development of spores, and so favours the life of the
alga. Flowering annuals similarly may be preserved many years by
prevention of flowering.
Algee.
Classification of Nostoc.—In the second fasciculus of MM.
Bornet and Thuret’s ‘ Notes algologiques,’ M. Bornet gives a full life-
history of the genus Nostoc, including the germination of the spores
and the development of the hormogonia, which display motility after
their escape. The thickening of the filaments takes place in many
Species, without having any specific value. With Nostoc M. Bornet
* Comptes Rendus, xciii. (1881). See also Mr, P. Geddes’ recent researches
on “ Animal Lichens,” ‘ Nature,’ xxv. (1882) pp. 303-5.
94 SUMMARY OF CURRENT RESEARCHES RELATING TO
unites Monormia Berk. and Hormosiphon Kg., and distinguishes the
following groups and species.
1. Intricata. Aquatic, softly gelatinous, without definite form,
often floating :—N. Hederule Men., tenuissimum Rbh., Linkia Roth.,
intricatum Men., crispulum Rbh., piscinale Kg., carneum Ag., rivulare
Kg.
2. Gelatinosa. Fixed; soft and gelatinous. Cells of the young
filament elongated cylindrical. Spores large, elongated :—WN. spongie-
forme Ag., gelatinosum Shousboe, ellipsosporum Rbh.
8. Humifusa. Terrestrial. At first globular, afterwards coalescent
and gelatinous, forming coatings adherent to the substratum. Spores
smooth :—N. collinum Kg., muscorum Ag. var. tenax Thur., Passerint-
anum De Not., humifusum Carm., calcicola Bréb., foliaceum Morg.
4. Communia. ‘Terrestrial, occasionally aquatic. At first globu-
lar, subsequently tongue-shaped, flat and irregular, not attached to
the substratum :—N. cimiflorum Tourn. (commune Vauch.).
5. Spherica. Globular, or often irregularly round when they
grow larger. Surface firm and resistent:—N. sphcericum Vauch.,
rupestre Kg., macrosporum Men., sphaeroides Kg., ceruleum Lyngb.,
minutissimum Kg., gregarium Thur., edule Mont., and Berk., pruni-
forme Ag.
6. Verrucosa, Aquatic; rounded or disk-shaped, at first solid, then
hollow, protected by a firm tough membrane. Filaments delicate,
distant, and somewhat curved in the middle, crowded and much bent
at the ends:—N. verrucosum Vauch. » par melioides Kg.
7. Zetterstedtiana. Aquatic ; ‘globular, Hangs warty, divides
readily into separable segments :—WN. Zetterstedtianum Aresch.
8. Flagelliformia. Terrestrial; narrow, linear, forming dichoto-
gmously divided bands :—WN. flagelliforme Berk.
Diatoms of Thames Mud.*—Dr. F. Bossey has investigated the
fresh- and salt-water diatoms found in mud-banks in the Thames, for
the purpose of showing the influence of the flood and ebb tides on their
formation, and gives the details of the result in an elaborate table.
Mud taken from seven different localities showed the following
proportions of fresh-water and salt forms :—
Fresh water. Salt.
Half a mile above Teddington Lock 66 0
One mile below Teddington Li Lock . 54 0
Kew . oe ; 52 37
Blackwall sig hake Hear 39 45
Estuary of the Thames .. .. .. 9 60
Dr. Bossey considers that in face of these facts the study of the
natural history of the Thames mud affords important evidence in
support of the position taken up by the Conservators of the Thames,
that the mud-banks forming in the river owe their origin to the.
discharge of matters from the outlets of the main-drainage system,
* Proc. Holmesdale Nat. Hist. Club, 2 pp. and a table.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 95
MICROSCOPY.
a. Instruments, Accessories, &c.*
Goltzsch’s Binocular Microscope.t—We give the description of
this Microscope, translated from the author’s German original, with
slight modifications only.
“This Microscope (Fig. 8), which is simple to the highest
imaginable degree, is calculated to obviate a number of theoretical
and practical objections
which may be raised
against instruments of
the same kind hitherto
described. In particular
- we get rid of —
(1) All difficulty in
combining the images
and all strain to the
eyes.
(2) All variation in
magnitude and distinct-
ness, as also in the ad-
justment of the images.
(8) All difficulty in
accommodating the in-
strument for different
widths between the
eyes.
(4) The influence
which the thickness of
the glass prisms, ana-
logous to the known
influence of the thick- !
ne f the rin = GTI
Be cise ccs co =
the course of the rays.
And lastly, instead of the double reflection, which is not avoided
in any of the instruments known, there is only a single reflection for
each half of the rays.}
All these advantages are obtained by a slight modification in the
manner in which the images are produced. Whilst in the case of the
compound Microscope the object must always be a little beyond the ~
focal point, and in the simple Microscope is generally nearer, in
the new arrangement it is brought to the focus itself, so that the
pencils of rays proceeding from the different points of the object,
UO
WE a=
)
AUNT
jun
* In this section are also included optical notes, notices of books relating to
the Microscope, and miscellaneous microscopical notes. ,
+ Carl’s Repert. f. Exper.-Physik, 1879, pp. 653-6 (1 fig.). Zeitschr. f.
Mikr,, ii. (1879) p. 166-9.
t The author appears not to have seen the Stephenson binocular.
96 SUMMARY OF CURRENT RESEARCHES RELATING TO
although their inclination to the axis is different, leave the objective
as pencils of parallel rays, and therefore of themselves produce no
image, or rather one at an infinite distance. The convergence of the
pencils of rays requisite to produce a real image is effected after-
wards by means of the eye-pieces, which consequently it would be
more correct to regard as telescopes, though they consist, like ordinary
microscopical eye-pieces, only of two plano-convex lenses of crown
glass, the ratio between their focal lengths being about 1:3. It will
be seen at once that, by employing this telescopic eye-piece to receive
the pencils of rays emerging parallel from the objective and coming
as it were from an infinite distance, it is not necessary that Micro-
scopes thus constructed should be of a fixed length. The length may
be altered at will without producing any change in the amplification
and distinctness of the image after it has been once obtained, provided
the telescopic eye-piece is so adjusted, by means of a draw-tube
arrangement, that distant objects can be clearly seen by it. It is
equally obvious how, by this process, the exact parallelism of the
pencils of rays emerging from the objective, and consequently the
position of the object in the focus, is regulated and known. This
furnishes us with a basis which renders it possible to obtain such a
direction for each half of the pencil of rays by a single reflection that
each eye can take in one of the halves.
In the original axis of the Microscope there are placed two glass
prisms, a smaller, A, Fig. 4, and a larger one B, which are fixed in
such a manner that the smaller prism
Fic. 4, causes one half of the rays and the larger
prism the other half to be diverted from
the axis under different angles by total
reflection. The two pencils D E of
parallel rays, are directed into the eye-
pieces through two tubes which converge
slightly towards the lower extremity.
The original axis of the Microscope hes
horizontally, and on the right of the
observer is the objective C, the stage,
and the illuminating apparatus; the
observer looks down from above (in a
E D direction inclined as may be desired)
through the two converging tubes,
directly upon the horizontal axis and
with each eye over one of the two reflect-
ing prisms. The first of these of course
projects only as far as the axis, so as to
leave half the opening free for the second.
They are so arranged on the axis that
they, with the eye-pieces to which they
are attached, can be moved by rack and
pinion so that their distance apart corresponds with the distance
between the eyes of the observer, without the image being affected
by the difference or alteration in the course traversed by the pencils
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 97
up to the first lens of the eye-piece, their rays being parallel. To
this parallelism it is due likewise that every disturbing effect (like
that which the thickness of the cover-glass exerts) by the prisms on
the transmitted pencil is excluded, for such effects can only be pro-
duced by converging or diverging pencils.
The mode of using an instrument so constructed does not differ
from that of an ordinary Microscope, except that first the two eye-
pieces must be removed and adjusted for infinite distance, and then
replaced. By means of the adjusting movement the left eye-piece
tube is then put in such a position that with proper illumination the
two diaphragm apertures of equal size, which are inside the eye-
pieces, are seen without effort as one ; an object being now introduced
and brought into focus, the plastic image infallibly appears, and
cannot be seen double. To produce this effect in perfection, however,
-the position of the prisms must be so adjusted that the images
together with the diaphragm apertures become merged into one com-
plete whole, and the impression is produced of looking through a
round opening at the object which is behind. After this position of
the prisms has been once fixed no focussing that may be necessary
alters the effect. The figure shows that the half of the rays which
pass to the second prism is that furthest from the observer; in the
opposite case the effect would be pseudoscopic.
Plane mirrors of glass may be used instead of the prisms, but
the surfaces of both the prisms and the mirrors must of course be
perfect. The prism which is inserted half-way, A, is best made
equilateral, because with a rectangular one the total reflection might be
questionable, and the edge is better; the other may be rectangular,
and should be of such a size that when the first is re-
moved it can take in and reflect the full pencil of rays;
we then have a monocular Microscope. It is obvious that
instead of the eye-pieces described, actual achromatic
telescopes could be used.”
Hartnack’s Demonstration Microscope.* — This
(Fig. 5) consists of a tube, carrying eye-piece and objective,
fixed to a frame by which it can be held in the hand. A
micrometer screw a serves for focussing the object which
is fixed to the circular stage by clamps. The continua-
tion of the stage forms a metallic drum, at the lower end
of which is a convex lens L to concentrate light on the
object. A diaphragm-disk is inserted in the drum with
a portion of its margin projecting on one side so as to be
revolved by the finger.
Lacaze-Duthiers’ Microscope with Rotating Foot—M. Nachet
has supplied us with a drawing (Fig. 6) of a Microscope similar to
that which we described at p. 873 of Vol. III. It is the device of
Professor H. de Lacaze-Duthiers.
The speciality of the instrument is that the bottom of the pillar
* Thanhoffer’s ‘Das Mikroskop und seine Anwendung,’ 1880, p. 55
(i fig.).
Ser. 2.—Vot. II. H
98 SUMMARY OF CURRENT RESEARCHES RELATING TO
is attached to a movable ring so that the rotation is on the base and
not on the stage (as in the larger Nachet models), the mirror remaining
fixed.
Fig. 6.
The special object of the design is stated to have been to reduce
the height of the instrument as much as possible, the method adopted
for the rotation “allowing the stage to be less elevated above the
table and thinner.”
Nachet’s Portable Microscope. — This Microscope is shown in
Figs. 7 and 8 set up for use as a table Microscope. Fig. 8 is intended
to show its application to the observation and dissection of large
surfaces or objects contained in small troughs or tubs. By loosening
the milled ring just above the stage (A, Fig. 8, C, Fig. 9) the com-
pound body can be removed, and an arm L carrying a lens or
doublet substituted. To put the instrument in its box (Fig. 11), the
stage P (Fig. 10) is turned completely over on the pivot O, and the
base is then only 4°5 cm. in height. The box is 19 cm. x 11 cm. x
6 cm.
The instrument seems to be an excellent solution of the problem
of constructing a Microscope which shall be really “portable” and
at the same time quite steady for ordinary use.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 99
Mic 3
ab || a
ee
|
100 SUMMARY OF CURRENT RESEARCHES RELATING TO
Parkes’s “ Drawing-room”’ Microscope.—The peculiarity of
this Microscope (apart from its title and golden colour) consists in
the revival of the “magnetic bar adjustment” to the stage, a device
originated by Mr. G. Busk.
Piffard’s Skin Microscope.—Dr. Stowell recalls * the Microscope
for the examination of the skin, devised by Dr. H. G. Piffard,t to
obviate the inconveniences attendant upon a simple lens of high
power, which “often involves a constrained position of the head and
neck, and in some cases an unpleasant proximity to the subject under
investigation.”
Dr. Piffard’s description is as follows :—* A (Fig. 12) represents
the body of a binocular Microscope made by Nachet, from which the
Fig. 13.
ic EA
HT
Fie. 12.
a |
=. SS =
reflecting prism situated above the objective was removed, and another
of the same focus but double the size substituted. B is a double nose-
C is the pinion for
piece carrying two objectives of different powers.
fine adjustment (raising and lowering the horizontal arm) ; and D the
clamping screw for coarse adjustment, the whole apparatus sliding up
and down the rod. E is a rod, five feet in length, which supports the
other apparatus, and is itself supported by a cast-iron foot not shown in
* ‘The Microscope,’ i. (1881) pp. 33-8. (1 fig.).
‘An Elementary Treatise on Diseases of the Skin, for the use of Students
t
and Practitioners, (8vo, London and New York, 1876.) See pp. 32-41. (1 fig.)
—_— -—_——.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 101
the drawing. Other adjustments permit the body of the Microscope to
be placed in a horizontal or any other desired position. . . . With the
instrument described, any portion of the integument, from the scalp
to the sole of the feet, can be conveniently examined, and a prolonged
examination can be made without fatigue to the observer.. It is an
instrument which I cannot too highly recommend to those desiring a
thorough knowledge of the surface aspect of the skin and its lesions.”
Robin’s Dissecting Microscope.—This (made by MM. Nachet) is
shown in Fig. 13, with their erecting eye-piece. The stage is arranged
so as to provide rests for the hands on either side of the dissecting
plate. :
Briicke Lens.—A description of this lens (Fig. 14), much in use
on the Continent, does not appear in any of the English books on the
- Microscope. We take the following from M. Robin’s treatise.*
“To remedy the inconvenience of the lens being too close to the
object in all but low powers, Charles Chevalier in his ‘Manuel du
Fia. 15,
Micrographe’ (1839) proposed ‘to place above a doublet a concave
achromatic lens, the distance of which could be varied at pleasure.
The effect of this combination is to increase the magnifying power
and lengthen the focus. Thus arranged, this instrument will be the
most powerful of all simple Microscopes, and the space available for
scalpels, needles, &c., will be much greater than with a doublet alone.
The further the concave lens is removed from the latter, the greater
will be the amplification.’ This combination, applied to lenses for
examining the eye and skin, allows the use of doublets which leave
* Robin, C., ‘ Traité du Microscope et des Injections,’ 2nd ed. (8vo, Paris,
1877), pp. 33-4 (1 fig.).
102 SUMMARY OF CURRENT RESEARCHES RELATING TO
a considerable distance above the object, and it is this idea which
has governed the construction of the Briicke lens.
“The lens has a very long focus, and the construction is that of
the Galileo telescope as applied to opera-glasses, but the amplification
of the objective is much greater than that usually obtained in opera-
glasses. ‘The focus is about 6 cm., and the power three to eight times.
The latter power is obtained by lengthening the tube, by which means
the distance between the two lenses is much enlarged and the amplifi-
cation increased without inconveniently modifying the focus.
“This lens may be used in place of the body of a compound
Microscope when it is desired to dissect or to find small objects, or it
can be adapted to a simple Microscope or lens-holder with from 3 to
8 cm. between the object and objective.”
Kiinckel d’Herculais devised .a holder for the lens shown in
Fig. 15. By tightening the screw on the horizontal arm the “jaws”
are separated or closed. The arm can be lengthened if desired and
also raised or lowered by the rack and pinion. L is the place for the
lens and O for doublets.
The Model Stand.*—Mr. J. D. Cox discusses the changes that
have taken place in microscope-stands with a view of determining
which will be of permanent value and should form part of the features
of a complete stand, and thus summarizes the essential requisites
which ought to be embodied in every instrument intended for real
scientific use.
1. A firm and rigid arm having the general character of the
Jackson model, carrying the body of the instrument, with coarse and
fine adjustments conveniently placed below the body, with perfectly
even and reliable motion.
2. A firm ring as the basis of the stage, to which any form of
stage-plate, plain with clips, glass, or mechanical, may be adapted and
interchanged. Nearly every microscopist has work to do for which a
mechanical stage is almost indispensable, such as micrometric measure-
ments, and the systematic sweeping of a slide to make sure that every
part has been examined. There should be no rack and pinion move-
ment for revolving the stage as it can be better done with the fingers,
nor a centering adjustment unless the instrument is intended for
goniometry. The stage thin enough to allow the use of light of at
least 70° obliquity from the axis of the instrument.
In regard to the requisite of reversibility for the stage, Mr. Cox
points out that in nearly every department of natural science (and not
for diatoms only) there is need of the occasional use of light of
extreme obliquity upon dry mounts and from the mirror alone, so.
that an easily reversible stage is desirable. If, however, immersion
illuminators came to be used for dry mounts as well as those in
balsam + a reversible stage would not be necessary, as a ray incident
at 41° only would emerge at the maximum obliquity of 90°.
3. A grooved bar—immovable and not swinging—for the support
* Amer. Jour. Micr., vi. (1881) pp. 89-95 (4 figs.).
+ This should read “ for dry objectives as well as immersion.” Balsam mounts
are on the same footing as dry mounts when a dry objective is used,
by by
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 103
of the substage with centering screws and which may or may not be
fitted with rack and pinion movement. No illuminating apparatus to
be attached to the bottom of the stage proper. The diaphragm with
tapering nose so that it can be racked up close to the bottom of the
slide.
4. The mirror-bar to swing on the optical centre of the instru-
ment above as well as below the stage, and to have a sliding extension
so as to increase the distance between the mirror and the stage without
changing the angle of the incident light.
5. Such form of base as will permit the mirror to be swung
laterally when the instrument is in upright position.
Mr. Cox objects to the substage and mirror-bar swinging together,
on the ground that it is then necessary to attach “the immersion
illuminators to the bottom of the stage by some special means, such
as bayonet catch, screw in the stage-well, &c.,” and he advises that all
such apparatus should be used in the substage for which it was in
fact devised. He suggests and figures an attachment to carry an
immersion illuminator, consisting of a movable elbow-piece on a
slotted arm sliding on a pin that screws on the outer end of a short
right-angled dove-tail slide fitting into a corresponding bar cast on
the substage carrier that racks or slides on the fixed tail-piece. This
appears to us, however, a complicated way of applying a simple im-
mersion illuminator such as the hemispherical lens, and we cannot
see any objection to mounting the lens in a disk to fit into the stage-
well or the under surface of the rotating stage plate.
For use with the Continental stands that are not provided with
mechanical stages, Mr. Zeiss mounts the lens in a disk of brass which
drops into the bevelled central stage opening, the plane face is then
flush with the surface of the stage.
Denomination of Eye-pieces and Standard Gauges for same.—
The Committee appointed by the Council in October last to consider
the question of standard gauges for eye-pieces (and substages) duly
presented their report, which was thereupon ordered to be printed
and circulated amongst the members of the Council, and is now
under consideration.
Subsequently to the report being made, the following circular
was received by some of the English opticians from a committee of
the American Society of Microscopists, unfortunately too late to be
laid before the Committee.
“1st Question.—Please give list of various eye-pieces or oculars for
the Microscope made by you, with construction (Huyghenian, ortho-
scopic, periscopic, &c., &ec.), with the equivalent amplifying power of
each, at a standard distance of 10 English inches or 254 mm.
2. Please state how you determine the amplifying power of your
eye-pieces.
3. Do you consider it desirable that a uniform nomenclature
(with reference to amplifying power) of eye-pieces should be adopted
by makers of Microscopes ?
4, Will you adopt such a nomenclature if decided upon by this
Society ?
104 SUMMARY OF CURRENT RESEARCHES RELATING TO
5. Please suggest such a nomenclature which seems to you most
generally applicable and desirable.
6. Do you consider it desirable that eye-pieces should be so con-
structed—by means of a shoulder or other device on the longer ones—
that all should pass the same distance into the tube of the Microscope,
thereby preserving the blackening of the inside of the microscope-
tube ?
7. Please give inside diameter of microscope-tube, or draw-tube
where there is one, or outside diameter of that portion of eye-piece
fitting into the microscope-tube for each size of stand made by you.
8. Do you consider it desirable that two, or three, or more standard
diameters of tube for Microscopes be generally adopted with a view to
interchangeability of eye-pieces ?
9. Please suggest the number of sizes and the inside diameter of
tube in each case, which you would recommend for adoption.
10. Will you adopt a standard set of sizes if agreed upon and
recommended by this Society ?
11. Please give this committee the benefit of any suggestions not
included in the above answers.”
The inquiry of the American committee embraces a wider field
than that of the Society’s committee, which was limited to the ques-
tion of standard gauges for eye-pieces and substages, and does not
include a consideration of the proper denomination for eye-pieces,
though the present system of nomenclature is an even greater evil
than that of the numerous different sizes.
Every one feels the inconvenience of the Continental method of
numbering or lettering objectives, a special table being necessary to
enable the relative powers of Monsieur A’s No. 2, and Herr B’s
No. 3 to be compared; the English plan of denoting the objective
by inches and fractions of an inch is obviously preferable.
Having adopted this improvement, however, and even being accus-
tomed to wonder how our Continental brethren can still tolerate so
barbarous a system of marking objectives, it is remarkable that
the designation of eye-pieces should have been allowed to remain
on the principle abandoned for objectives, and that the letters A, B,
C, D, &c., by which they are known, should still express absolutely
nothing as to their magnifying power, beyond the fact that I) is to
some undefined extent more powerful than C,C than B, and Bthan A;
so that not only is it impossible to compare the eye-pieces of dif-
ferent makers, but it is not possible to do so in the case of the same
maker, unless the powers are actually known.
If eye-pieces were, however, denoted on the same principle as
objecs yr nothing whatever would be lost, and much would be
gained.
For instance, if the magnifying power of a }-inch objective with
a C eye-piece is required, it will be 500 or 750, according as the eye-
piece is that of one or the other maker. If, however, instead of
being labelled C (or No. 3), the eye-pieces were called 2-inch or
l-inch, the necessary calculation (50 x 15 = 750 or 50 x10 = 500)
is instantly made.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 105
TABLE OF MAGNIFYING POWERS.
- OBJEC-
TIVES. EYE-PIECES,
Beck’s 1 ea y; Beck’s 4
lpowell’s 1 Se 4 Powell’s 3) Ross’s C. | Beck’s 3.) Powell’s i Beck ra Powell’s 5.] Ross’s F.
Ross’s A. Ross’s B, Ross’s D. |” y
nearly.*
a
is Focat LENGTH.
B|t.e
z Z | Qin. | 1iin.| lin. | Zin. Zin. | Lin. | Hefei, || geftne |) eer.
4 Fy
a zs Macnrryine Power.
8 4
ie 5 | 7% | 10 | 12 15 20 | 25 | so | 40
COMBINED AMPLIFICATION OF OBJECTIVES AND
EYE-PIECES.
in.
5 2 i) 10 15 20 25 30 40 50 60 80
4 23 124 182 25 314 374 50 624 te 100
3 31 162 25 334 412 50 662 834 100 1332
2 5 25 374 50 624 75 100 125 150 200
13 2) 334 50 662 832 100 1334 1662 200 2662
1 10 |} 50 75 100 125 150 200 250 300 400
=8| 12% 624 932 125 1562 1873 250 3122 375 500
3 132 662 100 1331 1662 200 2662 3331 400 5332
2) 15 7) 112% 150 1873 225 300 375 450 600
4 20 |} 100 150 200 250 300 400 500 600 800
| 25 | 125 1873 250 3124 375 500 625 7930 1000
4 30 |f 150 225 300 375 450 600 750 900 1200
§,| 333} 1662 250 3331 4162 500 6662 334 1000 13331
t 40 200 300 400 500 600 800 1000 1200 1600
1) 50 250 375 500 625 750 1000 1250 1500 2000
2 60 300 450 600 750 900 1200 1500 1800 2400
+} '7O }j 350 525 700 875 1050 1400 1750 2100 2800
+ 80 400 600 800 1000 1200 1600 2000 2400 3200
3 90 |} 450 675 900 1125 1350 1800 2250 2700 3600
wo 100 500 750 1000 1250 1500 2000 2500 3000 4000
+ 110 550 825 1100 1375 1650 2200 . 2750 3300 4400
ay 120 600 900 1200 1500 1800 2400 3000 3600 4800
is 1380 650 975 1300 1625 1950 2600 3250 3900 5200
a 140 700 1050 1400 1750 2100 2800 3500 4200 5600
7,|150 750 1125 1500 1875 2250 3000 3750 4500 6000
ay 160 800 1200 1600 2000 2400 3200 4000 4800 6400
z,|170 850 1275 1700 2125 2550 3400 4250 5100 6800
is 180 900 1250 1800 2250 2700 3600 4500 5400 7200
,| 190 950 1425 1900 2375 2850 3800 4750 9700 7600
ab 200 |} 1000 1500 | 2000 2500 3000 4000 5000 6000 8000
=| 250 |f 1250 1875 2500 3125 3750 5000 6250 7500 } 10000
as 300 |i 1500 2250 3000 3750 4500 6000 7500 9000 } 12000
z,|400 |} 2000 3000 4000 5000 6000 8000 10000 | 12000 4} 16000
sb 500 |f 2500 3750 5000 6250 7500 } 10000 12500 | 15000 | 20000
z2|600 |} 3000 4500 6000 7500 9000 } 12000 15000 | 18000 | 24000
a 800 |} 4000 6000 8000 {10000 {12000 } 16000 20000 | 24000 32000
* Powell and Lealand’s No. 2 = 7°4, and Beck’s No. 2 and Ross’s B = 8 magnifying power or
respectively 2; less and , more than the figures given in this column.
106 SUMMARY OF CURRENT RESEARCHES RELATING TO
Judging from past experience, it will probably be too much to
expect that the desired change should take place all at once, and
that the A, B, O, &c., or Nos. 1, 2, 3, &c., should forthwith be swept
away, but we would venture to suggest that the power of the eye-piece
should be indicated in the catalogues and elsewhere, as well as the old
title, and if this were done we are sure that the latter would soon be
wholly disused.
The tables of magnifying powers issued by opticians are at
present, in many cases, of a very misleading character, not so much
from the fact that the objectives are underrated—a true +/,-inch being
called a 1-inch—but that, according to the tables, one and the same
eye-piece magnifies differently when it is used with different objec-
tives !
We have accordingly compiled the annexed table of magnifying
powers for ready reference. It includes all the more usual objectives,
and the full series of eye-pieces of Messrs. Beck, Powell, and Ross.
It will be noticed that the magnifying powers of the No. 1 or A
agree in all three cases, those of the No. 2 or B slightly varying,
being 8, 7°4, and 8. It would be an improvement if they could
all be made 73, which would preserve the uniformity of the series.
The No. 8 or C vary greatly, being 15, 10, and 12}. The No. 4 or
D agree, whilst No. 5 or E are 25, 30, and 25.
We think that an ideal series should run thus:—No. 1 = 5,
No. 2 = 71, No. 3 = 123, No. 4 = 20, No. 5 = 30.
With the exception of the 3, ,, and 4, all the objectives
included in the table are actually constructed by English or foreign
opticians. As objectives are, however, not uncommonly found to
vary somewhat from the designated focal lengths, the figures for the
3, z7, and +}, have been retained.
The length of tube is assumed as usual to be 10 inches.
Braham’s Microgoniometer.*—At a recent meeting of the Bath
Microscopical Society, Mr. Braham described a microgoniometer for
measuring the angles of crystals. “The body of the microscope-tube
is formed at right angles. A rectangular prism is so adjusted that
the plane of the hypothenuse is at an angle of 45 degrees to the axis
of rotation. On bringing any crystal into the centre of the field, a
fibre in the focus of the eye-piece is made to coincide with either of
its edges so that the degrees passed through can easily be read.
Thus, as the instrument measures a magnified image of the crystal,
and the object itself is stationary, it will readily be seen that the
angles of any crystal visible under the highest powers of the Micro-
scope can easily be measured.”
Watson's Sliding-box Nose-piece.—Messrs. Watson have recently
contrived a sliding-box nose-piece to carry (1) the vertical illuminator
(Fig. 16), or (2) the analyzing prism (Fig. 17) of the polarizing
apparatus, or (3) the binocular prism. The application of an extra
nose-piece in this form appears to be convenient. Experience must,
* Engl. Mech., xxxiy. (1881) p. 277.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 107
however, decide how far it is advisable to add to Microscopes focussing
at the nose-piece, extra appliances tending to affect the delicate fitting
of the fine adjustment.
Fic. 16.
Deby’s Screw-Collar Adjustment.—Mr. J. Deby suggests that the
application of a worm-wheel and tangent screw to the screw-collar
adjustment of objectives (Fig. 18) would
be found more convenient than the usual Fie. 18.
system for adjusting the corrections with
accuracy. The device, as figured, would
not permit the objective to be enclosed ¢
in the ordinary brass box; but, as sug-
gested by Mr. Beck, the tangent pinion
might be cut off short and provided with
a slightly tapering square head upon
which the milled head would fit when
required.
Number of Lenses required in
Achromatic Objectives. * —Mr. W.
Harkness discusses the number of
lenses required in an achromatic objec-
tive consisting of infinitely thin lenses
in contact, in order that with any given
law of dispersion whatever, the greatest possible number of light-rays
of different degrees of refrangibility may be brought to a common
focus.
For any system of thin lenses in contact we have
1
a7 — 1) A, + ( —1) A.+ (@s — 1A; + ete. (1)
the number of terms being unlimited. For a dispersion formula we
write
#= (0) (2)
The form of ¢ (A) is unknown, but there will be no loss of gene-
* Bull. Phil. Soc. Washington, iii. (1878-80) pp. 65-7. Smithsonian Mise.
Collections, xx. (1881).
108 SUMMARY OF CURRENT RESEARCHES RELATING TO
rality if it is developed in a series arranged according to the powers
of X. We, therefore, have
B=atba™+ca™ + cr? + ete, (3)
in which a, b, c, etc., are constants, and the number of terms may be
taken as great as is desired.
Let us also put
C=A,@,—1)+ A,G = 1+ ArG, =—1)+ ete.
D=A,}6, +A,b, + A; 2; + ete. (4)
E= A,c, + A,c, + A, c,; + ete.
F = A,e, + A, e, + A; e; + etc.
etc. etc. etc.
the number of these equations, and the number of terms in the right-
hand member of each of them, being the same as the number of terms
in the right-hand member of (8). Now substituting for the p’s in
(1) their values in terms of the auxiliaries C, D, E, etc., of the equa-
tions (4), we find
= C+ Da" + EA 4 Fa + ete (5)
Considering as the abscissa, and fas the ordinate, this is the
equation of the focal curve. Its first derivative, with respect to f and
A, is
df =i =i
= —f(mDan—1 + nEa—! + ete.), (6)
which, as is well known, expresses for every point of the curve the
tangent of the angle made by the tangent line with the axis of
abscissas. The number of rays of different degrees of refrangibility
which can be brought to a common focus will evidently be the same
as the number of times that the focal curve intersects the focal plane.
But the focal plane is necessarily parallel to the axis of abscissas ;
and therefore the greatest possible number of intersections of the
curve with the plane can only exceed by one the number of tangents
which can be drawn parallel to the axis of abscissas. To find these
tangents we equate (6) to zero, and obtain
0 =mDa"—1+ nEA"—!1-+ ete. (7)
As dX can never be either zero, negative, or imaginary, we have
to consider only the real positive roots of this equation; each of
which corresponds to a tangent. 'To make the number of tangents as
great as possible, the quantities D, E, F, etc., must be independent of
each other ; which will be the case when the right-hand members of
the equations (4) contain as many A’s as there are powers of A in the
dispersion formula (4). All the terms of (7) contain the common
factor X"-". Taking it out we have
—mD=nEA"—-”+ pF a-" + ete, (8)
from which it is evident that the number of real positive roots in (7)
will always be one less than the number of powers of A in(3). Hence
we conclude that :—
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 109
In any system of infinitely thin lenses in contact, the number of
lenses required to bring the greatest possible number of light-rays of
different degrees of refrangibility to a common focus is the same as
the number of different powers of A contained in the dispersion
formula employed.
The method made use of in arriving at this result has been
adopted, because it brings out clearly the geometrical relations of the
problem. The result itself is evident from a mere inspection of
equation (5), which cannot possess more real positive roots than it has
independent auxiliaries, D, E, F, etc.
Colour Corrections of Achromatic Objectives.*—The following
abstract is published of a paper by W. Harkness :—
1. From any three pieces of glass suitable for making a corrected
objective, but not fulfilling the conditions necessary for the complete
destruction of the secondary spectrnm, it will always be possible to
select two pieces from which a double objective can be made that
will be superior to any triple objective made from all three of the
ieces.
: 2. The colour correction of any objective is completely defined
by stating the wave-length of the light for which it gives the minimum
focal distance.
3. An objective is properly corrected for any given purpose
when its minimum focal distance corresponds to rays of the wave-
length which is most efficient for that purpose. For example: in an
objective corrected for visual purposes, the rays which seem brightest
to the human eye should have the minimum focal-distance; while in
an objective intended for photographic work the rays which produce
the greatest effect upon silver bromo-iodide should have the minimum
focal- distance.
4. In the case of a double achromatic, the secondary spectrum
(or in other words, the diameter, at its intersection with the focal
plane, of the cone of rays having the maximum focal length) is abso-
lutely independent both of the focal length of the combination, and
of the curves of its lenses; and depends solely upon the aperture
of the combination, and the physical properties of the materials
composing it.
5. When the focal curve of an objective is known, and the
relative intensity, for the purpose for which the objective is corrected,
of light of every wave-length is also known; then the exact position
which the focal plane should occupy can be readily calculated.
Incidentally, it may be remarked that in an objective corrected
for photographic purposes the interval between the maximum and
minimum focal distance is less than in one corrected for visual pur-
poses. Hence a photographic objective has less secondary spectrum,
and is better adapted for spectroscopic work, than a visual objective.
Verification of Objectives.— The editor of the ‘ Northern
Microscopist’ undertakes, for a nominal fee of 1s. 6d., to verify
* Bull. Phil. Soc. Washington, iii. (1878-80) pp. 39-40. Smithsonian Misc.
Coll., xx. (1881).
110 SUMMARY OF CURRENT RESEARCHES RELATING TO
objectives sent to him in regard to their amplifying power, working
distance, absolute size of field, and real aperture.*
Schultze’s Tadpole - Slide.t — This slide (or “ microscopic
aquarium”) (Fig. 19) was devised for showing the circulation of the
blood or the development of the blood-vessels in the larvee of the frog
and triton. To one side of a thick slide is fastened by means of
Fic. 19.
Canada balsam a piece of another slide, cut as represented at A, and
to the other side a second piece, of the shape seen at A’, so that there
is a small cell in the centre of the slide, of the form shown in section
in the figure. A cover-glass d closes the cell.
To place the larva e in the cell, the cover-glass is taken off
and the larva fished out of the water in a small watch-glass, and
poured with the water into the cell. By manipulating with a brush,
its head is brought into the hollow of the glass at A, and the tail
placed on the sloping surface at A’. The cover is then quickly
replaced, care being taken that the cell is full of water. The animal
is excluded from air by the water, which, when it evaporates, can be
replaced with the brush. In this way the circulation of the blood in
the tail may be observed for hours at a time.
Stokes’ Tadpole-Slide.t—Mr. A. W. Stokes fastens two pieces of
a vulcanite ring (Fig. 20) to an ordinary slide so as to form an oval cell
just large enough for the body of the tadpole, the tail projecting
through an opening in the cell. Close to the latter a square of thin
Fic. 20.
cover-glass is cemented by Canada balsam so as to raise the tail to a
level with the body. On each side of this are cemented two small
oblong pieces of thin glass forming a cell for the tail to liein. A
square of cover-glass over the body, and another over the tail, will
keep the tadpole in place.
* North. Microscopist, i. (1881) pp. 253-7.
+ Thanhoffer’s ‘ Das Mikroskop und seine Anwendung,’ 1880, pp. 148-9 (1 fig.).
+ Ann. Rep. Postal Mier. Soc., 1881, p. 13 (1 fig.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 111
“Swinging Substage,” or “Swinging Tail-piece.”—At the time
this contrivance was first introduced it was known asa “Swinging
Tail-piece,” but since that time the term “substage” has been
almost universally substituted. The earlier name is obviously, how-
ever, the more appropriate, as it is not simply the substage which
swings, but the mirror also, and we intend to adopt in future the
expression “swinging tail-piece.”
Value of Swinging Tail-pieces.—In addition to the opinions
cited at p. 666 of Vol. I. (1881), the following has been published
during the past year :—
‘Mr. J. D. Cox, in the paper above referred to (see p. 102),
considers that the swinging of the mirror-bar on the optical centre of
the instrument is a positive improvement, but that the swinging of
the substage is of very doubtful value. “In the former case several
real advantages are gained. First, the mirror is kept at its proper
focal distance from the object. Second, it may be swung above the
stage for illumination of opaque objects. Third, it allows the instru-
ment to be used for measuring aperture of object-glasses, by converting
it into Smith’s ‘ Universal Apertometer.’* But when we ask for
the advantages of swinging the substage with illuminating apparatus,
it is difficult to find them. It is plain that we don’t want to swing
the polariscope, the parabola, the dark wells, the Webster condenser,
the wide-angled achromatic condenser, or the immersion illuminators,
and could not if we would, for the form and mounting of these acces-
sories is inconsistent with doing so. The question must practically
be narrowed to the desirability of swinging the diaphragm and the
low-angled achromatic condenser. Of course none of the flat dia-
phragms can be swung in this manner, and no advantage seems to be
found in the use of the sharp-nosed diaphragms with oblique light.
The fact is that there are advantages in taking oblique light directly
from the mirror ; for the chromatic fringes at the margin of the illu-
mination often enable the microscopist to modify the light in a way
to get increased resolution by turning the mirror so as to take the
most lateral rays and those nearest the blue end of the spectrum.
More range in quality of illumination can be got by the practised
hand in this way than by the oblique use of the diaphragm.
“In the use of an achromatic condenser, it must be a very low
angle indeed which will work far enough from the bottom of the
stage to allow much swinging to right or left, especially when we
take into account the fact that the centering of the substage
becomes more important when it is swung away from the axis of the
instrument.
“The centering arrangement of the substage will occupy so
much lateral room that it can be swung but a little way before
striking the stage. Again, any achromatic condenser of even
moderate angle can be swung very little to right or left before its
marginal rays will become parallel to the bottom of the slide con-
taining the object under examination, and they then, of course, cease
* See this Journal, ii. (1879) p. 775.
112 SUMMARY OF CURRENT RESEARCHES RELATING TO
to penetrate to the object or be of use for illumination. Still,
again, experience seems to prove very conclusively that the most
effective as well as the simplest arrangement for securing oblique
light (otherwise than from the mirror alone) is by the prism, the
traverse lens, the Wenham ‘half button,’ or other immersion sub-
stage illuminators. These considerations lead strongly to the
conclusion that the swinging of the substage is useless.”
Ranvier’s Microscope-Lamp.*—This (Fig. 21) is described as
consisting essentially of a metal globe, which covers the cobalt glass
lamp chimney “and prevents the radiation of heat.” Four openings
with plano-convex lenses conduct the light to four Microscopes.
“The light can be so subdued that it is possible to work a long time
Fic. 21,
— Tu 7a
— i T _—
p IMTINTATT UOUDLUUUNUONDUONUOQSUOUNNOBULLUOUDDDOOUUOOTOUOTONONOTUUOOLONODUUn00)UDUIQOUOLODOOUIOOSICOONNONTTITG
in the evening without straining the eyes, for which reason the lamp
is preferable to all other kinds of illuminating apparatus. The
cobalt glass is an essential feature, because the yellow-colour of the
lamp-light is thereby obviated, and the sensation of white is produced.
Certain shades of yellow and blue, as is well known, stand in
relationship to each other as complementary colours, that is they
produce white.”
Hollow Glass Sphere as a Condenser,t—Mr. F. Kitton describes
the effects of using a glass globe filled with water for the purpose of
condensing light upon the object. This was used by some of the early
microscopists,{ though it appears soon to have fallen into disuse, as it
* Thanhoffer’s ‘ Das Mikroskop und seine Anwendung,’ 1880, pp. 73-4 (1 fig.).
t Sci.-Gossip, 1881, pp. 274-5 (1 fig.).
} Hooke, ‘ Micrographia,’ 1665 ; Ledermiiller, ‘ Mikroskopische Gemiiths- und
Augen-Ergozung,’ 1762.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 113
is not mentioned by Adams in his ‘ Micrographia Illustrata, 1771,
or in his ‘Essays on the Microscope, 1787. Mr. Kitton tried it first
with a }-inch objective upon Pleurosigma angulatum, using oblique
light from the mirror ; the strize came out very distinctly. On removing
the globe, the striz vanished and required a more oblique ray to
render them again visible. Tried on Synedra robusta, it resolved the
striz into beads. With a 2 inch, and not altering the previous position
of the mirror, a ‘“‘black field” was obtained. The object Haliomma
Humboldtii was seen with beautiful effect, appearing as though
illuminated by intense moonlight with a slight green tinge and
delightfully cool to the eye. It is also to be recommended with
polarized light for softness of tint and impenetrable blackness of field
when the prisms are crossed. A globe (6 inches in diameter) should
be used, filled with a dilute solution of sulphate of copper (about
- S$ ounce of saturated solution to 1 pint of water). The mixture must
be filtered if ordinary water is used, though the intensity of colour
is somewhat a matter of taste. The distance of the globe from the
lamp should be about two or three inches; from the globe to the
mirror about eight to twelve inches.
Stein’s small Microphotographic Apparatus.*—Fig. 22 shows
Stein’s microphotographic apparatus which, though small and simple,
is said to answer its purpose completely. It
is on the plan of Harting’s apparatus and Fig. 22.
consists of a cone F which is inserted into ;
the tube M of the Microscope instead of an Sim;
eye-piece, a plate of ground-glass is fixed
to the top, and on this the image can be
focussed, the observer’s head being covered
with a black cloth. The ground-glass plate
is replaced by the prepared sensitive plate
and the image can then be readily photo-
graphed.
Ranvier’s Myo-Spectroscope.t—In this
simple and ingenious instrument (available
for rapid superficial demonstrations) a prism
is replaced by the muscular tissue, the trans-
verse strie of the muscular bundles acting on white light like a
grating and producing spectra.
The muscles of the frog are the most suitable for observation, and
especially the sartorius muscle, the bundles of which are parallel.
The muscle having been taken with care from a living frog, it
is dried for some hours in a stove at 40° C., after having been
stretched with pins ona piece of cork. The muscle is then planed on
both sides with a sharp scalpel, soaked in turpentine, and mounted in
Canada balsam.
* Thanhoffer’s ‘Das Mikroskop und seine Anwendung,’ 1880, p. 48 (1 fig.).
4 Ranvier’s ‘Traité technique d’Histologie,’ Paris, 1878-80, pp. 316-19
(1 fig.).
Ser. 2.—Vor. II. I
114 SUMMARY OF CURRENT RESEARCHES RELATING TO
The myo-spectroscope is shown in Fig. 23. T’ isa tube 12 cm. long
and 4 em. in diameter, blackened internally, and closed at one end by
FG. 23.
a diaphragm with a vertical slit /’ half a millimetre in breadth. At
the other end is a stage plate with a central hole o (5 cm.): The
preparation of muscle is placed in the clips in front of the latter hole
and so that the axes of the muscular bundles are at right angles to
the slit f’. On looking through the hole, whilst the instrument is
directed to a light, spectra will be seen on the right or left of the slit.
To observe the absorption-bands of hemoglobin, a second tube T is
- added to the instrument, sliding over T’ and having a diaphragm with a
large vertical slit f’’ in which is placed a tube S containing a solution
of blood. Having first seen that the muscle givesa clear spectrum,
T with S is replaced and the two absorption-bands of hemoglobin
will be seen in the spectrum.
As the spectrum produced by a grating is more extended according
as the lines of the grating are closer together, we are led to investigate
whether a muscle at the moment of contraction gives a wider spectrum
than when at rest. The lower tendon of the sartorius muscle of a frog
is separated from the tibia and the muscle stretched before a slit and
it will be seen that on slightly stretching the muscle, the spectrum
will be narrow and close to the slit. When the muscle is contracted
the converse phenomena are produced, and when it is excited by a
current and attains its maximum of contraction the width of the spectra
and their distance from the slit are much angmented.
The muscles of different animals thus examined do not give
identical spectra. For example, those of the muscles of the frog are
broader than those of the white muscles of the rabbit in the ratio of
9 : 7. The transverse striation is therefore finer in the former case
than in the latter.
Standard for Micrometry.*—The Philosophical Society of
Washington publishes the reply given by Dr. J. J. Woodward to the
committee of the Microscopical section of the Troy Scientific
Association who asked answers to the following questions : t—
“1. Is it expedient at present to adopt a standard for micrometry ?
2. If so, should the English or the metric system be employed ?
* Bull. Phil. Soc. Washington, iii. (1878-80) pp. 22-4; Smithsonian Mise.
Coll., xx. (1881).
+ See this Journal, ii. (1879) pp. 154-9.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 115
3. What unit, within the system selected, is most eligible ?
4, What steps should be taken to obtain a suitable standard
measure of this unit ?
5. How can this standard micrometer be best preserved and made
useful to all parties concerned ? ”
The reply was as follows :—
“1. 1 am in favour of the adoption of a suitable standard for
micrometry by the American Society of Microscopists at their next
meeting.
2. For this particular purpose I think the metric system offers so
many conveniences that I favour its employment.
3. The selection of an eligible unit within the system involves, it
appears to me, two distinct questions: A. How shall the stage-
micrometer be ruled? B. How shall the measurements made, be
expressed in speech or writing ?
A. The object of the stage-micrometer is chiefly to give values to
the divisions of the eye-piece micrometer with the power used in any
given case. It should be long enough to be used for this purpose with
the lowest powers of the compound Microscope, and have a part of its
length ruled sufficiently close to answer the same end with the highest
powers. I favour the adoption of a standard scale a centimetre long
ruled in millimetres, and one of these ruled in hundredths. I have
used stage-micrometers ruled in thousandths of a millimetre, but
regard such divisions as inconveniently close for this purpose. To
measure in thousandths of a millimetre as the unit, which is very
convenient in a large number of cases, the simplest way is to use a
magnifying power that will make ten divisions of the eye-piece micro-
meter exactly coincide with one-hundredth of a millimetre on the
stage-micrometer. The glass eye-piece micrometer should have a
scale a centimetre long ruled in one hundred parts. By increasing
the power so that a larger number than ten of these divisions shall
correspond to one-hundredth of a millimetre on the stage-micrometer,
a unit of any degree of minuteness that may be required for any
special work can be obtained up to the limits of distinct vision with
the Microscope.
B. But although I regard the hundredth of a millimetre as a very
eligible dimension for the closest divisions of the stage-micrometer,
when it comes to expressing the results of our measurement in speech
or writing, I do not think it is convenient to use the hundredth of a
millimetre as the unit of expression. It is too large, and the results
of too many measurements would still have to be expressed in decimal
fractions. The thousandth of a millimetre is much more convenient
as a unit of expression, and I would advise that microscopists should
agree to call this dimension a micron, and represent it in writing by
the Greek letter 1. This dimension has already been adopted as the
unit of expression by a number of European microscopists, who
represent it by the same Greek letter, but call it a micro-millimetre.
The term micron should, I think, be preferred because well known
to scientific men other than microscopists, having for some time been
used in expressing minute differences by those officially engaged in
I 2
116 SUMMARY OF CURRENT RESEARCHES RELATING TO
preparing standard measures of length, and having been adopted by
the International Metric Commission. I think it running an
unnecessary risk of confusion to select any other than this well-
recognized term for the dimension in question.
4&5. To obtain a suitable standard stage-micrometer, I would
advise each microscopical society to select one ruled, as above
described, by any person in whom they have confidence, and to satisfy
themselves by comparison of the several parts with each other, by
means of the same part of the eye-piece micrometer, that the divisions
agree among themselves. This is comparatively easily done; the
real difficulty will be to determine whether the whole scale is really
a centimetre long. To ascertain this, I would advise each micro-
scopical society to send its standard micrometer to the Superintendent
of the Coast Survey at Washington, with the request that he will have
it compared with a recognized standard in the Bureau of Weights and
Measures, and return it with a report of the error, if any. I have
reason to believe that such requests would be promptly and courteously
responded to. Each society should then preserve the standard thus
obtained for the sole purpose of enabling its members to compare
their stage-micrometers with it. I think this plan much wiser than
to relegate the question to any one of the ingenious men who are
endeavouring in this country, with considerable success, to make
accurate rulings on glass, and I should anticipate better results from
it than from the appointment of a special committee of the American
Society of Microscopists to prepare a standard scale.
In conclusion, I readily admit that so long as the English
microscopists continue to express the results of their measurements in
decimals of an English inch, there will be American microscopists
who will do the same, either for all purposes or for particular work,
and of course it is very desirable that these measurements also should
be accurate. The stage-micrometers on this system in the market are
usually ruled in hundredths and thousandths of an inch. The latter
divisions are too wide to give values to the eye-piece micrometer with
the higher powers, while the five-thousandths, ten-thousandths, or even
finer divisions, ruled also on some of these micrometers, are incon-
veniently close. I would advise the makers to rule such micrometers
four-tenths of an inch long, divided into hundredths of an inch, one of
the hundredths being subdivided into ten, another into twenty-five
spaces. These latter spaces, each representing one twenty-five-
hundredth of an inch, sufficiently approximate the hundredth of a
millimetre to be used with equal convenience with the higher powers.
The scale on the glass eye-piece micrometer, used with these stage-
micrometers, should be, if specially made for the purpose, four-tenths
of an inch long, divided into one hundred parts, each one two-hundred-
and-fiftieth of an inch; but these divisions would so closly approximate
those of the metric eye-piece micrometer proposed, that it might be
used without inconvenience instead. Where it is thought worth
while by a microscopical society to procure a standard scale of this
kind, it should be sent to the Coast Survey Office for measurement, as
in the case of the metric scales.”
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 117
Rogers’ Micrometers.— Prof. W. A. Rogers, of Cambridge, U.S.A.,
recently offered, as we announced,* to present a ruled stage micro-
meter to any one who would undertake to examine its divisions and
publish the results. Mr.T. 8. Bazley having accepted the proposal,
now details the result of the investigation.t ‘“ Placed on the stage,
and viewed with a two-thirds objective, and a dark field, the ruled
lines, which are not filled in with a dark pigment as is common,
sparkle like streaks of diamonds; and under this illumination a
singular appearance is noticed. Insome of the lines a slight internal
splintering of the glass has apparently followed the course of the
ruling-point, giving an effect of deeper cuts in certain places. But,
as this effect is invisible with a bright field, and as there is certainly
no variation in the width of the several lines, it probably arises solely
from the nature of the glass; and the more so, as these apparently
deeper cuts do not often extend for the entire length of a line, and
sometimes occur side by side for a few lines.
“The micrometer is of the ordinary 3 by 1 size. The ruled portion
is a centimetre in length, and contains 1000 spaces, subdivided at
every fifth and tenth, the lines being thus 0:01 mm. apart. The width of
the band, neglecting those lines that project, is 1-375 mm. Every
tenth line is1°6 mm. long, and the principal spaces of 6:1 mm. are
subdivided by a shorter pro-
longation of the fifth lines, Fig, 24.
which measure 1°55 mm.
These measurements are the
average only, for the lengths
of the individual lines vary a
few thousandths of a milli-
metre, and the lower edge of
the band is not consequently
strictly in one straight line.
The terminations of the lines
at the upper edge, indepen-
dently of those projecting at
every fifth and tenth, are not
in the same straight line
either. These deviate in a
symmetrical manner; four
lines between two long ones
having their ends equal and straight, while the ends of the next four
form a gentle convex curve. All the lines at this, which may be con-
sidered the reading edge of the band, are terminated by singular
hooks, suggestive of the curved handle of a walking-stick (see Fig.
24); they differ somewhat in size and character, but have all the
same direction, and are probably due to the stopping, lifting, and
reversal, of the cutting diamond.
“The objectives used were a series by several makers (dry, as well
as immersion adapted to various media) up to Zeiss’s L, equivalent to
* See this Journal, i. (1881) p. 678.
+ Engl. Mech., xxxiv. (1881) pp. 341-2 (1 fig.).
118 SUMMARY OF CURRENT RESEARCHES RELATING TO
sz; the lines of the band being well defined under all of them;
and the eye-piece micrometer, Jackson’s form, and a small spider-line
micrometer. -The former depends a good deal for its result upon an
estimation to tenths of its graduations, and can hardly be susceptible
of the accuracy which should be attained with a well-made ‘ wire
micrometer.’ The latter was therefore adopted and provided with
additional draw-tubes, for use, either as an eye-piece in the usual
manner, or in the substage, giving an aerial image of the spider-lines
as proposed by Dr. Pigott.* This latter method, however, so far as
my own experience goes, is more ingenious than effective ; principally
because all vibration of the micrometer in that position is magnified
by the whole power of the Microscope. There is one advantage
possessed by Jackson’s in the spring action, which moves the whole
scale, and consequently its zero point, with extreme nicety. In the
spider-line micrometer, one wire is generally fixed, and the only way
to bring a given point of an object under the Microscope to coincide
with that wire is by the screw action of the stage, which, with a high
power, is far too sensitive and rapid. To obviate this difficulty, a
traversing movement to the extent of a fifth of an inch, controlled by
a screw of fine pitch, was added to the small micrometer between its
screw-plate and draw-tube. By this means any given line on the ruled
band, after being brought approximately into position with the stage
movement, could be accurately bisected by the fixed wire of the micro-
meter. The objectives finally selected were a + for the measurement
of the principal subdivisions of 0°05 mm. each, and a 1, imm. for the
close spaces. These objectives gave the most convenient decimal values ;
the former by suitable adjustment of the draw-tube giving *00025 mm.
as the equivalent of one division of the micrometer divided head (50
divisions to one turn); and the latter -0001 mm. Both glasses were
by Beck, and their magnifying powers, with the positive eye-piece
employed, were 950 and 2500 respectively. Of course the eye-piece
could be changed at pleasure, without altering the ratio of scale to
image. Thefine movement of the Microscope employed is on its
main tube; its action propels or withdraws the nose-piece, thus
possibly interfering with the value, as adjusted by the lengthening
draw-tube, of the micrometer scale in terms of a given unit. It
proved, however, by actual experiment, using a power of 1000
diameters, that an alteration of the fiftieth of an inch in the distance
from eye-piece to stage, made no perceptible change in the ratio
between the micrometer in the eye-piece and that on the stage, so any
supposed error in measurement from this cause may be dismissed as
visionary. All kinds of illumination were tried, the preference being
given to that described [in this Journal, I. (1881) p. 666], using
the concave mirror without condenser, at an obliquity of about 40°,
and a thin metal plate attached below the stage, at such an angle
that no rays from the lamp can reach the object, except by reflection
from the inclined mirror. With the light so directed, each line of
the band was evenly divided, longitudinally, into a dark half and a
light half, giving much facility for the exact superposition of a
* Mon. Micr. Journ., ix. p. 3.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 119
micrometer-wire upon the centre of the image of any line. In
examining the spaces seriatim, there was some risk of losing count,
and as a means of reference, a scale of figures, photographed by
Mr. J. Mayall, jun., to the exact length of a centimetre, was pasted
at the upper edge of the band, so that the principal graduations of
the latter could be identified with a low power.
“ Coming, at last, to the examination of the plate ruled by Prof.
Rogers, perhaps its most distinguishing feature is the perfect straight-
ness and similarity of the individual lines. The stage micrometers
commonly met with are so deficient in this respect, that it is impos-
sible to obtain equal distances from different parts of the same two
lines of the scale. But with the rulings of Prof. Rogers no such
inequality exists. The spider-lines at the eye-piece may be set to any
interval of lines on his micrometer, and the scale will rigidly indicate
the same distance at any other part of the band, whether above,
below, or on either side the position first selected. As to the actual
width of the lines themselves, I make it to be ‘001 mm. almost
exactly. After all these precautions for the study of this micrometer,
perhaps a list of small, though definite, errata may be looked for ; but
I have carefully verified the principal intervals of the band, and a
large number, taken at hazard, of the 1000 close spaces, and have
detected no discrepancies whatever. The only possible criticism that
occurs to me is that the projecting lines at the reading edge are
perhaps needlessly Jong, and that if the ‘ walking-stick hooks’ could
be transferred to the other side of the band, it would be an improve-
ment. I believe the ruling to be as accurate as mechanical means.
can produce; and though there is no means of deciding whether the
spaces are true subdivisions of the French metre, the perfection of
the subdivisions themselves is a tolerably sure guarantee that the
Professor took every care to verify his unit to begin with.”
Section of “Histology and Microscopy” at the American
Association.—At the last meeting of the American Association for the
Advancement of Science, a section of “Histology and Microscopy,” in
place of the previously existing sub-section of Microscopy, was
established, to rank on the same footing as the other sections of the
Association, and to be represented on the Standing Committee, its
Chairman being ex officio a Vice-President.
Structure of Cotton Fibre.*—Dr. F. H. Bowman has published
an elaborate investigation into the structure of cotton fibre, in which
he gives a general account of the plant botanically, and deals with the
typical structure of a cotton fibre, both in regard to the mechanical
arrangement of its ultimate parts, and chemically. A full consideration
is given to the variations from the type structure which are found to
exist and the extent to which any variation in the ultimate fibre may
affect its use in the manufacturing process.
The book is illustrated with plates of typical and other cotton
* Bowman, F. H., ‘The Structure of the Cotton Fibre in its relation to
technical applications,’ xvi. and 211 pp., 5 figs. and 12 pls. 8yo, Manchester,
1881.
120 SUMMARY OF CURRENT RESEARCHES RELATING TO
fibres and with coloured plates, showing their appearance when dyed
with turmeric yellow, indigo blue, &c.
The value of the Microscope with ordinary and polarized light,
and with dyed and undyed fibres, is throughout made a special feature,
and the book is to be welcomed as a noteworthy addition to the, at
present, very scanty literature relating to the practical applications of
the Microscope to manufactures. We should imagine that both silk
and woollen manufacturers would be benefited by similar treatises on
silk and wool.
The limit of microscopical vision is, on pp. 156-7, treated as
synonymous with the limit of microscopical resolution, and in any
future references to the subject care should be taken to show that the
latter refers exclusively to the power.of distinguishing as separate two
lines or other objects close together, the limit of which is half the wave-
length in the medium employed x sin. uw, whilst the vision of isolated
minute objects is only limited by the sensitiveness of the particular
observer's retina, the distribution of light, &c. Limit of “ visibility ”
is distinct from the limit of “ visible separation.”
g. Collecting, Mounting and Examining Objects, &c.
Durable Preparations of Microscopical Organisms.*—Professor
G. Entz describes the method used by him for mounting microscopical
organisms, Protozoa, Rotifera, &c., preceded by an historical review
of the processes hitherto adopted.
Ehrenberg + used a dry process which answered well only for
certain objects. Its use may be somewhat extended by soaking the
dried preparation in 1 part distilled water, 1 part glycerine, and (in
a large quantity) 1-2 drops of picric acid. The shrivelled parts
swell out and look very life-like. Amongst the organisms capable
of being so treated are the Volvocineze, Chlamydomonads, the lori-
cated Huglene (£. acus and E. Spirogyra) Peridines, the tests of
Rhizopods, tubes of Melicerta, Ciliata with resisting cuticles (as
Stentor igneus, Epistylis plicatilis, and fine chitinous elements, such as
the masticatory apparatus of Rotifera and small Nematodes. The
protoplasmic parts of organisms are of course entirely lost by this
method.
Later still, Du Plessis { suggested glycerine coloured with chro-
mate of potash, and Duncker § in 1877 exhibited Rotifers, Protozoa,
and Alge, which were highly commended by such authorities as
Cohn, Stein, and Leuckhart, and which showed the fine parts in a
most wonderful manner. Unhappily they were not permanent. In
a few weeks brown oily drops began to make their appearance in the
fluid, and ultimately the protoplasm also browned, so that they are
now useless. Duncker never published his method, but the author
considers it probable that the basis of the fluid he used was rectified
* Zool. Anzeig., iv. (1881) pp. 575-80.
+ Abh. K. Akad. Wiss. Berlin, 1835, p. 141; 1862, p. 39.
{ Arch. f. Naturg., 1864, ii. Band, p. 162.
§ See this Journal, i. (1878) p. 221.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 121
pyroligneous acid, which, allowed to run in under the cover-glass
in small quantities, killed and fixed the organisms in their natural
form.
After referring to the methods suggested by Certes,* Biitschli,t
and Thanhoffer and Davida,t the author describes that which he
has adopted in the hope of obtaining the same beautiful results as
Duncker, but at the same time more durable.
“ According to my experience, various means, long known, are
adapted for fixing the smallest and most delicate organisms; for
instance, rectified pyroligneous acid, the ‘liqueur salin hydrargy-
rique’ of Blanchard, in the mixture which Arnold Lang recommends
for preserving marine Planarians, § and which has been also used by
Paradi for fixing fresh-water Turbellarians with the best results;
also picric acid ; and lastly, what Paul Mayer has so strongly recom-
mended || for the lower animals, viz. picro-sulphurie acid, which
certainly should have the preference over the others. All these
media (the list of which is by no means exhausted), kill microscopical
organisms instantaneously, without destroying their organization.
Flagella and cilia, the suctorial disks of the Acinete, and even the
fine pseudopodia of the Heliozoa can be fixed as well as the pedicel of
the rapidly-jerking Vorticelle. Also the muscle of the pedicel, the
contractile vacuoles, and the cesophagus and digestive vacuoles.
Huglence and Amebe may be fixed in their various changing shapes.
Rotifera die mostly with their peristomes moderately withdrawn, and
Vorticelle the same; but examples may be obtained from COarchesium-
and Epistylis-stems, which are fixed in the act of lively rotation.
Infusoria are fixed in the same life-like state, in the act of fission or
conjugation, and Vorticelle in the bud form of conjugation. The
nucleated elements also come out very prominently, even the nucleolar
capsules can be splendidly preserved for further study, and their
striation retained. Spongille, Hydre, small Nematodes, Tardigrades,
delicate insect larvee, and ciliated cells (e.g. of the gills of mussels)
can be excellently fixed and preserved. To obtain durable prepara-
tions, however, it is absolutely necessary to remove the fluid which
has completed its work in the process of fixing, as it might injure the
fine organisms by longer action, afterwards placing the preparation in
a fluid which is suited to it.
“ My procedure is essentially the same as that which Paul Mayer
used for treating the lower marine animals with picro-sulphuric
acid. ;
“JT place the Protozoa and other microscopical organisms with
the Algz, sediment, or other objects to which they are affixed or
between which they move, with some water in a watch-glass, then
drop in a few drops of the fixing fluid, which I allow to act only 1-2
minutes. I then pour off the fluid carefully, or simply lift the
* Comptes Rendus, Ixxxviii. (1879) p. 433. See this Journal, ii. (1879)
pp. 331 and 763.
t Zool. Jahresber., 1879, p. 173.
{ Thanhoffer, L. v., ‘Das Mikroskop und seine Anwendung,’ 1880, p. 110.
§ Zool. Anzeig., i. (1878) p. 14. See this Journal, i. (1878) p. 256,
|| MT. Zool. Stat. Neap., ii. (1880) pp. 1-27.
122 SUMMARY OF CURRENT RESEARCHES RELATING TO
preparation out with a pencil or scalpel, in order to transfer it at
once into a larger quantity of alcohol, which must not be too strong.
Half an hour is usually enough to withdraw the fixing fluid and
replace it by alcohol, in which it may remain a longer time without
damage. For removing the chlorophyll colouring-matter of many
Infusoria, and also the Algee in the preparation, a longer stay in
alcohol is of course necessary, replacing it by clear alcohol when it
has become coloured.
“Microscopical organisms thus treated are ready to be at once
mounted in dilute glycerine (1 part of distilled water to 1 of
glycerine). But colouring must not be neglected. Among the
colouring materials commonly used (carmine, hematoxylin, and various
aniline dyes), carmine certainly is to be preferred, because it is
not bleached in glycerine, and moreover does not colour everything
with one tint like the aniline dyes, but principally the nuclear ele-
ments. Preparations transferred from alcohol to carmine are mostly
coloured sufficiently in 10-20 minutes, only loricated forms as
Euglena, Spirogyra and species of Phacus, the Peridinex, &c., require
several hours to make their nuclei sufficiently prominent. Before
being transferred into dilute glycerine, the preparations must of
course be put into distilled water, and remain until the yellow picric
acid is drawn out, and the preparation shows a nice rose colour.
“ By the above process beautiful and instructive preparations are
obtained, which when carefully mounted show no further change. I
have a fairly considerable collection of different Protozoa which have
not altered in the least for 6-7 months, and are adapted both for
demonstration and for detailed study.”
Preparing Anthers.*—J. Rataboul proposes an improved method
for preparing anthers, to show the fibrous cells of their walls.
The ordinary method of preparation is to leave the anthers in
water until the walls swell, and by triturating with a quill to loosen
some shreds of tissue. If any cells are found the tissue must be
washed with care to remove pollen-grains and air-bubbles. These
manipulations are long, delicate, and difficult, and are not always
successful; and the author’s method is to place the anthers in 90° or
100° alcohol for 4-5 minutes, triturating grosso modo, and immediately
putting it in distilled water. The cells open as if by enchantment,
the pollen-grains are readily detached, the alcohol dissipates the
air-bubbles, and by this process a much larger portion of the anthers
can be obtained for examination.
Herpell’s Method of Preparing Fungi for the Herbarium.j—
G. Herpell announces some improvements on his method previously
published, and which we have already described.}
In the method proposed for the preservation of the fleshy parts he
has no improvement to suggest; but in the preparation of the spores
various slight emendations have presented themselves,
* Bull. Soc. Belg. Micr., vii. (1881) pp. exliv—v.
+ SB. Bot. Ver. Prov. Brandenburg, June 24, 1881.
} See this Journal, i. (1881) p. 136.
‘Sr
jes:
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 123
The fixing of the coloured spores with lac on white paper answers
completely ; but, in the case of the Leucospori, only those of species
of Russula and Lactarius unite firmly with the resin of the lac. On
the other hand, the mode of fixing the white spores on blue cardboard
simply with gelatine appears to answer in all cases ; but the solution
should be somewhat more dilute than previously stated. The best
fluid is a warm solution of 1 part gelatine in a mixture of 150 parts
water and 150 parts alcohol. This answers with species of Russula
and Lactarius, while with Agaricus (Collybia) radicatus so concentrated
a solution as 1 part gelatine in 30 parts water is necessary. The
writer gives a list of a number of species, with the strength of solution
required in each case. Some spores can be fixed on blue cardboard
by the use of pure water only. In some cases, again, it is necessary
to heat the solution strongly. Agaricus (Collybia) maculatus, A. (C.)
velutipes, and Marasimus peronatus require a different treatment, which
is described.
The author found the same results with the fluid recommended by
Patouillard (2 parts mastic in 15 parts ether) as with the lac; the
resin does not in all cases combine well with the white spores.
The ether has some advantages in penetrating the paper more rapidly
and completely, but, on the whole, Herpell prefers the use of
alcohol.
Dissociation of Gland-Elements.*—Cauderau finds boiling the
mucous membrane of the stomach in a solution of nitrate of soda a
very good process for isolating the glands and gland-elements, but the
constituent parts of the tissues become too brittle. This defect can be
obviated by a previous immersion of some minutes in osmic acid.
The cells will then remain admirably preserved after boiling for three
hours, but can scarcely be stained at all. The following combination
is therefore recommended :—One part of Miiller’s fluid is diluted with
two parts of water and about 30 to 40 grammes of the sodic nitrate is
dissolved in a litre of the mixture. Boiling for three hours in this
compound is sufficient to break up the mucous membrane of the
stomach. ‘The maceration, besides acting on the glands, extends to
the muscular coat.
Method of Preparing and Mounting Soft Tissues,t— The con-
clusions arrived at with regard to the structure of the nervous centres
by means of the successive action of bichromate of potash and nitrate
of silver will certainly receive confirmation from this method, which
we owe to Professor C. Golgi. It has the double advantage of
enabling us to stain the nerve-cells black within a given time, and of
turning out preparations which may be kept for a long period in the
ordinary mounting media.
The pieces of tissue are hardened to the necessary degree in
Miller’s fluid, or in solutions of bichromate of potash, whose strength
* Gaz. méd. de Paris, No. 45, pp. 577-8. Cf. Jahresber. Anat. u. Physiol.,
Vili. pp. 13-14.
+ Rendiconti R. Istit. Lombard., xii. pp. 206-10. Cf. Jahresber. Anat. u.
Physiol., viii. pp. 12-13.
124 SUMMARY OF CURRENT RESEARCHES RELATING TO
is gradually increased from 1 to 24} per cent. The pieces must not
be more than 1 to 2 em. thick, a large proportion of fluid must be used,
and it must be frequently changed. In from 15 to 20 days the pieces
are put into corrosive sublimate solution } to 4 per cent. in strength.
The reaction requires at least 8 to 10 days, and during this time
the liquid must be daily renewed. The pieces gradually change
colour and acquire the appearance of fresh brain-substance. They may
be allowed to remain even for a longer time in the solution, which
serves at the same time to harden them. Sections which are to be
kept must be repeatedly washed, else crystals and other deposits appear
upon them and alter the appearance under the Microscope. They keep
admirably well in glycerine, which is perhaps better for the purpose
than Canada balsam and dammar. By this method the ganglion-cells
with their processes are acted upon; their nuclei are often left visible ;
the elementary constituents of the walls of the vessels, and especially
the smooth muscular fibres (muscle fibre-cells), are also brought out.
Golgi reports having had good results from the application of this
treatment to the cortex of the cerebrum, negative results in the case
of the spinal cord, and but slight success with the cerebellum. The
author calls the reaction an apparently black one, inasmuch as the
elements on which it has taken effect appear white under surface
illumination, and black only by transmitted light.
Preservation of Anatomical Specimens.*— L. Gerlach recom-
mends the glycerine process of Van Vetter, which has been some-
what modified, firstly by Stieda and then by Gerlach himself. Stieda’s
recipe is as follows :—Make a mixture of 6 parts of glycerine, 1 of
brown sugar, and } part of saltpetre ; Gerlach uses 12 instead of 6 parts
of glycerine. The preparations are cleaned and laid in this liquid, in
which they remain from three to six weeks, according to their size. When
taken out they have a dark-brown colour and are quite firm; they are
then hung up in a chamber of the temperature of 12°-14° R. (59° to
634° Fahr.). In the course of eight to ten days they become soft and
flexible, but must be allowed to hang from two to six months longer,
to be available for demonstrations. The more glycerine used, the
lighter in colour the preparations remain. The method is best applied
to preparations of articulations, to sense organs (eye, ear), larynx, &e.
The formation of a crystalline precipitate, which sometimes appears
in the drying, is met by the increase in the proportion of glycerine
and a diminution of the saltpetre and sugar. If large objects are to be
set up, such as whole extremities with their muscles, or the thorax
with the ligaments dissected, pure glycerine is preferable to the cheap
crude article, for specimens turn out whiter and less hard in it,
Gerlach has used it for temporal bone with tympanum and auditory
ossicles, and obtained valuable preparations which may be employed
with great success to demonstrate the transmission of waves of sound
from the tympanum to the labyrinth.
Barff’s Preservative for Organic Substances.—A new preserva-
tive applicable to all animal and vegetable substances has been
* SB. phys-med. Soc. Erlangen, July 28, 1879. Cf. Jahresber. Anat.
u. Physiol., viii. pp. 112-13, and Jahresber. (Virchow and Hirsch) for 1879, p. 2.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 125
patented by Professor F. 8. Barff. It is a compound prepared by
mixing boracic acid with glycerine. The former is dissolved in the
latter by the aid of heat, the solution taking about four or five hours,
care being taken, however, that the temperature employed shall not be
SO excessive as to decompose the glycerine. 'To such solution or com-
pound a further quantity of boracic acid is added from time to time
until the boracic acid ceases to be dissolved. The compound resulting
when allowed to cool, is solid, and is called by the patentee
boroglyceride.
In order to employ the compound, a solution is prepared in water,
alcohol, or other suitable solvent, and the organic substances to be
operated upon, either immersed in or impregnated with such solutions.
Solutions may be prepared of various degrees of strength; but
Professor Barff finds that a solution consisting of about one part by
weight of the compound and forty parts by weight of water will give
good results ; other proportions may, however, be adopted for special
purposes. Solutions of the compound may be applied to the preser-
vation of all organic substances either animal or vegetable.
Injection-mass.*—L. Teichmann injects blood-vessels and lym-
phatic vessels with a mass which is fluid when cold; it is made with
finely powdered materials and linseed-oil varnish up to the consistency
of putty, and altered to that of honey or syrup as required, by volatile
liquids (such as ether and carbon disulphide). Prepared chalk,
zine white, &c., may be used, coloured with cinnabar, ultramarine,
chrome yellow, &c. Ordinary hand-pressure is not powerful enough,
so Teichmann makes use of syringes, such as those for injecting gutta-
percha, in which the piston is impelled by a screw arrangement.
In this way, even the finest and most elaborate ramifications of
the vessels may be readily and with certainty filled. The mass soon
stiffens, partly owing to transudation, partly to evaporation of the ether,
so that it does not ooze from vessels which may be cut through; it
remains soft for a certain time and is as hard as stone when the
preparation is finished. The advantages of this method are obvious.
Imbedding Delicate Organs,t—L. Frédéricq describes a method
by which pieces of tissue or organs, such as brains of small animals,
livers, kidneys, &z., are so thoroughly impregnated with paraffin that
they retain a firm consistence, do not shrink up, and keep as well as
the best casts of the organs. The tissue or organ is hardened by
placing in alcohol, first dilute, then absolute, for several days, is then
laid for several days in oil of turpentine, until transparent, when it
is transferred to paraffin melted in a water bath, and kept there at
a temperature of about 55° C. (it must not exceed 60°), for from two
to eight hours, according to the size of the object. It is removed and
dried while hot in a current of steam, by blotting-paper or otherwise,
and finally allowed to cool.
* SB. Math. Kl. Krakau. Akad., vii. pp. 108-58. Cf. Jahresber. (Virchow
and Hirsch) for 1879, p. 2.
+ Gaz. méd. de Paris, 1879, No. 4, pp. 45-6. Cf. Jahresber. Anat, u. Physiol.,
Vili. p. 12. ;
126 SUMMARY OF CURRENT RESEARCHES RELATING TO
‘Katsch’s Large Microtome.*—In this instrument (Fig. 25), a
stand, similar to that of a sewing-machine, supports a tray, across
which, in a diagonal direction, a small ledge is fixed. This is inclined
rather outwards, and on one end of
it the cutting knife rests, so as to
move steadily against the micro-
tome plate which rises a little above
the tray, and surrounds the pre-
paration. The plate itself is at
the end of a hollow cylinder fixed
to the tray, in which a massive
metal cylinder can be raised and
lowered by a screw underneath.
There are three knobs on the upper
part of this cylinder to fix the sub-
stance in which the preparation is
imbedded.
When the latter is cooled (which
is done by pouring water into the
tray) the section can be made.
A special advantage of this form
- of instrument is that sections can
= be cut under water, and that the
screw may be fixed by means of a
small click to the 3,5, mm. In
turning the screw the click is caught at every 5,55 mm., and gives
an audible signal.
—e
i
1)
f q
Y Wi
Cox’s ‘Simple Section-cutter for Beginners.’ {—In this, economy
and simplicity have been carried to at least their furthest practicable
limits, as the basis of the instrument is a sewing-machine cotton-reel,
and a Perry’s music binder. The cost does not exceed 2 or 3 pence.
Cutting Sections of very small Objects.{—H. Strasser adds
from 3 to 4 parts of tallow to the imbedding mixture recommended by
Kleinenberg (spermaceti 4 parts, castor-oil 1 part), and in order to be
able conveniently to arrange very small objects for cutting sections in
any required position, he places them in the mass while this is still
warm, between plates of mica; the temperature must never exceed
45° C. After cooling the mica plates may be readily separated from
the mass, which has the form of a thin sheet, and contains the object ;
it may be then fixed with heated pins in the desired position upon a
block of a substance not easily melted.
Mounting in Balsam.§—Dr. C. Seiler, in a paper contrasting
glycerine and balsam as mounting materials, gives the following as
a desirable modification of the old process of mounting in various
* Thanhoffer’s ‘Das Mikroskop und seine Anwendung,’ 1880, pp. 96-7 (1 fig.).
+ Ann. Rep. Postal Micr. Soc., 1881, pp. 12-13 (1 fig.)
t Morphol. Jahrbuch, v. (1879) p. 243. Cf. Zool. Jahresber. Naples, i. (for
1879) p. 35.
§ Proc. Amer. Soc. Micr., 1881, pp. 60-2.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 127
media, whereby the disadvantages attendant upon the use of balsam
are removed, so that it becomes the preferable method.
Take a clear sample of Canada balsam and evaporate it in a water
or sand bath to dryness; i.e. until it becomes brittle and resinous
when cold. Dissolve this while warm in warm absolute alcohol
(Squibbs’), and filter through absorbent cotton. Place the section,
after it has been stained, in weak alcohol (about :60), and allow it
to remain in a few minutes, then transfer it to -80, °95, and finally
to absolute alcohol, in which it should remain a few minutes also.
Then transfer it to the slide (which has been slightly warmed above
a spirit-lamp so as to remove all moisture), drain off all superfluous
alcohol, and place a drop of the alcoholic balsam solution on the
specimen. In a few seconds the latter will become transparent, when
it may be covered, and set aside to dry. In.damp weather, or when
breathed upon, a milky edge will be noticed on the drop of balsam,
which is caused by minute globules of water, which, however, may
readily be dispelled by the application of a little heat to the under
side of the slide. It will be seen that by the gradual dehydration of
the specimen, the danger of distortion of the histological elements
is materially diminished ; that by the omission of any clearing agent
the shrivelling is avoided as well as the solution of fat in the cells
prevented, for cold alcohol alone will not dissolve fat ; and finally by
evaporating the balsam to dryness all other constituents except the
pure balsam are driven off, so that the danger of crystallization is
avoided.
Mounting in Glycerine,*—Dr. 8. R. Holdsworth finds the follow-
ing plan to be efficacious in avoiding the difficulty found in getting rid
of the surplus glycerine when it has passed beyond the cover-glass,
He puts a very small drop of glycerine upon the object, just sufficient
that when the cover-glass is applied it will not extend to the margin.
A solution of Canada balsam in chloroform or benzoline is then run
in to fix the cover-glass, and not being miscible with the glycerine, an
air-space is formed between the two fluids which has not been found to
be detrimental. The slide can be finished with a ring of balsam or
other cement.
Smith’s Slides.j—The Editor of the ‘ American Monthly Micro-
scopical Journal’ writes:—‘“ Mr. J. Lees Smith, of this city, has
prepared some very attractive slides in this manner: the glass slips
are first coated with photographer’s ‘ granite varnish’ by flowing, just
as a plate is coated with collodion in photography. This coating of
varnish gives the slide the appearance of finely ground glass. It is
then placed on the turntable, and, by means of a knife-blade, the
varnish is entirely removed from a circular spot in the centre, just
large enough for the cell in which the mount is to be preserved.
The preparations we saw were mounted in glycerine, and the clear
and transparent cells were made of Brown’s rubber cement, which Mr.
Smith regards as a most excellent cement, especially for glycerine
* Ann. Rep. Postal Micr. Soc., 1881, p. 11.
t Amer. Mon. Micr. Journ., ii. (1881) p. 179.
128 SUMMARY OF CURRENT RESEARCHES RELATING TO
mounts. Imagine a slip of ground glass with a transparent spot in.
the centre, upon which objects can be mounted, and one can thus
form an idea of the appearance of these slides.”
Spring Clip Board.*—Mr. W. Stringfield gives the accompanying
sketch (Fig. 26) of the spring clip boards he has had in use for some
time, and which, for reducing the breakage of thin glass covers to a
minimum, economy of construction, and convenience of moving, far
Fic. 26.
surpass, he considers, any arrangement that has come under his notice.
They are made of mahogany, but of course pine or other wood can be
used. All, however, should be baked previously to finally planing up.
A is a piece of mahogany 12 x 7} x ? inches; B_ two strips,
each securely fastened down the centre of the base board A by
eleven screws; CC pieces of watch or crinoline steel, 38% inches
long, 2 inch wide, with a hole punched in either end to allow of a
small brass pin passing through for securing the pressers; D D small
pieces of phial corks; EK E EE four screws fitting in corresponding
holes drilled in the bottom of each board, thus allowing a number to
be placed one on the other without injury to the slides, and admitting
a free current of air.
Examination of Living Cartilage.j—J. M. Prudden found the
episternum of the frog, especially of Rana temporaria, an extremely
good object in which to examine cartilage in the living animal. A
moderately curarized frog should be taken, and an incision made in
the skin from the lower jaw to the middle of the sternum, and then
two cross cuts; the operator must turn back the edges of the skin,
and divide the submaxillary muscle, thus exposed, near the middle,
avoiding the large veins which pass inwards over the apex of the
episternum. The latter lies at the bottom of the incision, being
covered only by a somewhat loose connective tissue. If the delicate
lamine of connective tissue between the episternum and hyoid bone
are now cut through, and the head turned back at right angles to the
body, the episternum is extruded from the wound, projects forwards,
* Sci.-Gossip, 1881, p. 232 (1 fig.
)
+ Virchow’s Archiv, lxxv. pp. 185-98, Cf. Jahresber. Anat. u. Physiol.,
viii. pp. 11-12.
nS
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 129
and may be rendered accessible even to strong magnifying powers if
placed on a glass block of suitable size. For prolonged observations
the whole object may be attached to Thomas’s object-holder, with
arrangement for irrigation, and may be kept in the natural fresh
condition of life by irrigating with amniotic fluid or } per cent. salt
solution.
By this method Prudden was able, by irrigating with the latter
fluid, to observe the cartilage cells in the episternum of the frog
for many hours, in the living and fresh condition. Under these
circumstances the intercellular substance appears homogeneous,
the outline of the cell is very clear, and the cell-protoplasm has a
finely granular appearance, with bright globules near the nucleus;
the latter has a double contour, is penetrated internally by a number
of fine lines, which meet at broader internodes. In this form of
nucleus he could observe phenomena of movement, but could not
determine that any effect was produced upon these movements by
weak chemical reagents, by heat, or by electric currents. Under the
action of 1 to 8 per cent. salt solution the cells shrink back from
their walls, and are seen to be provided with numerous processes,
which radiate to the walls of the cavities; vacuoles are also formed
in the interior of the cells under these circumstances. When water
is added to the solution, the cells resume their original appearance.
Similar production of vacuoles under pathological conditions in cells,
which have in like manner the power of reverting to the normal
condition (Swetsky), the author believes to be explicable by an
increase in the density of the liquid which the tissues contain. If
the living episternum is irrigated with indifferent liquids and then
replaced, the cells appear quite unaltered at the end of nine weeks.
In an episternum which had been excised and placed in the lymph
sac of a frog, the cells were found to be filled with yellow drops,
soluble in ether, after five days, and the cell-nuclei stained with
carmine. An identical degeneration of the cells, accompanied by
susceptibility to staining with carmine, took place when the epister-
num was exposed and replaced after its cells had been killed by
chemical reagents or electric shocks. Carmine did not stain the
nuclei at all in the living cartilage, neither after irrigation with
2 per cent. salt solution, nor after subsequent dilution of this liquid
with water, nor when the episternum had been restored to the body for
some weeks; consequently the cells had not died. The author found
that even very weak solutions of iodine, and also carbolic acid solutions
of a greater strength than + per cent.—that is, solutions which are
actually employed in the treatment of affections of the joints—caused
the immediate death of the cells, so that when the tissue was subse-
quently replaced the degenerative processes just mentioned set in.
The author found that the cells of living cartilage collapsed under
a temperature of 58° C., in detached pieces at that of 50° C., a lower
temperature than that which Rollet found necessary.
Statoblasts of Lophopus crystallinus as a Test for High-power
Objectives.—Areolations of Isthmia nervosa.—Dr. John Anthony
writes :—“ TI forward an object which I think will be found of value
Ser. 2.—Vot. II. K
130 SUMMARY OF CURRENT RESEARCHES RELATING TO
as a test for high-power objectives, and which, not being a diatom or
very diaphanous, needs rather the quality of ‘resolution’ than that of
‘definition ’ to deal with it satisfactorily. I take it that a ‘test’ to
be of use should be fairly easily obtainable; that the specimens
should, from the nature of the structure, be uniform; and that to
merit the name of a ‘test’ it should not be too easily made out, even
by the best modern glasses.
“T am sanguine enough to think that the statoblast of Lophopus
erystallinus, which is easily procurable in any numbers, will be found
to meet these conditions. The difficult part is the structure of the
membrane, which seems to be stretched over the coarse hexagonal
framework of the statoblast. I have seen it well, but it tried my
fine =, of Tolles, and was most bright and clear with an excellent
zy homogeneous-immersion objective, which Mr. Tolles has just sent
tome. I found the more axial the illumination the better—obliquity
was fatal. I used a cap on my condenser of ;3,, the diameter of
condenser being 4, and it evidently aided the definition.
“While on high-power testing, let me say that the hexagonal
areolations seen in the apparent openings in Isthmia nervosa are
valuable for trying the qualities of +, ,4,, and 1, or more. The areo-
lations are not small, but so delicate as not to be seen at all by a poor
object-glass, while the better the quality of objective the more clearly
can they be made out, till they look like delicate network. I mention
this because I find the existence of this delicate structure is not
generally known; though I have used it for some years to try the
quality of objectives.”
Microscopical Structure of Malleable Metals.*—The following
observations have been made by Mr. J. V. Elsden on the minute
structure of metals which have been hammered into thin leaves.
Notwithstanding the great opacity of metals, it is quite possible to
procure, by chemical means, metallic leaves sufficiently thin to examine
beneath the Microscope, by transmitted light. Silver leaf, for instance,
when mounted upon a glass slip and immersed for a short time in
a solution of potassium cyanide, perchloride of iron, or iron-alum,
becomes reduced in thickness to any required extent. The structure
of silver leaf may also be conveniently examined by converting it into
a transparent salt by the action upon it of chlorine, iodine, or bromine.
Similar suitable means may also be found for rendering more or less
transparent most of the other metals which can be obtained in leaf.
An examination of such metallic sections will show two principal
types of structure, one being essentially granular, and the other
fibrous.
The granular metals, of which tin may be taken as an example,
present the appearance of exceedingly minute grains, each one being
perfectly isolated from its neighbours by still smaller interspaces.
The cohesion of such leaves is very small.
The fibrous metals, on the other hand, such as silver and gold,
have a very marked structure. Silver, especially, has the appearance
* ‘Nature, xxiii. (1881) p. 391.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. apt
of a mass of fine, elongated fibres, which are matted and interlaced in
a manner which very much-resembles hair. In gold, this fibrous
structure, although present, is far less marked. ‘The influence of
extreme pressure upon gold and silver seems to be, therefore, to
develope a definite internal structure. Gold and silver, in fact, appear
to behave in some respects like plastic bodies. When forced to
spread out in the direction of least resistance their molecules do not
move uniformly, but neighbouring molecules, having different velo-
cities, glide over one another, causing a pronounced arrangement of
particles in straight lines.
This development of a fibrous structure, by means of pressure, in
a homogeneous substance like silver, is an interesting lesson in expe-
rimental geology, which may serve to illustrate the probable origin
of the fibrous structure of the comparatively homogeneous limestones
of the Pyrenees, Scotland, and the Tyrol.
Sections of Fossil Coniferous Woods.—Voigt and Hochgesang of
Gottingen have issued (price 65 marks) a collection of seventy micro-
scopic slides of coniferous woods, fossil and recent, prepared by
Professor Goppert. The present collection is a first instalment only, -
and is devoted to the Araucarieze. Where possible, each species is
represented by three sections, one transverse, the second central or
radial, and the third cortical or tangential. Sections of recent woods
are placed side by side with those of the most nearly allied fossil
woods; as sections of an Araucaria (A. Cumninghami) and of a
Dammara (D. australis) by the side of the fossil Araucarites. The
preparations are arranged in a polished mahogany box with ledges,
and have been made on slides of white glass 50 x 33 mm., and
1'5 mm. thick, with polished edges, under square cover-glasses of
18 mm. length and breadth, in Canada balsam. Only those of the
recent Araucariez are under round cover-glasses of 20 mm. diam. in
glycerine. The sections have been made with the greatest care and
skill. Instead of the ordinary length of about 4 mm., these are
of double or treble that length, so as to render possible a more com-
plete examination. Special care has been taken to furnish sections
which illustrate the nature of the process of petrifaction.
Aeration of Laboratory Marine Aquaria.*—The plan shown in
Fig. 27 is recommended by M. Kunckel d’Herculais for aerating
a salt-water aquarium by means of a fall of fresh water.
The figure shows two aquaria, A being fresh-water and B salt-
water. In the first case the process is of course very simple, the
water from the pipe C passing down the tube H, air being obtained
through the tube F and pipe D which communicates with the open
air so as to prevent air being abstracted from the confined laboratory.
In the case of the salt-water aquarium B, the fresh-water passes
from the pipe C down the tube G into the bottle H, with three
openings, which holds about two litres, air being obtained as before
from the open air through D and the tube shown on the right. A
* See ‘Manuel de Zootomie,’ par A, Mojsisovics, traduit par J. L. de Lanessan
(8vo, Paris, 1881), pp. 61-6 (1 fig.).
Kee
132 SUMMARY OF CURRENT RESEARCHES, ETC.
third tube I conducts the air from the bottle to the aquarium, while
the water escapes from the bottle through the tap at the bottom. All
that is necessary is to regulate the flow into and out of the bottle in
such a way that the water shall be at a constant level. When this
has once been experimentally ascertained the aquarium may be left
Fic. 27.
TTA ATTN ATTA TT AAT ATA TTT
CH | (A ll | | A AUS INIA I MAA I lus
| ETT
| eC th AND A
| ER
| | | (|
| | = z = ie =
= IN Emi=
| SS =a + =
ULQUUUUNULLUNUNUAVA ALUN Il
I
RUFFLE
without fear day and night. If the bottle were allowed to get empty
the aeration would of course stop, while if it were filled the fresh
water would pass into the aquarium. In order to supply the loss
from evaporation a little fresh water should be added from time to
time, which will prevent the necessity for renewing with salt water.
The apparatus will pass 223 litres of air per hour through an
aquarium of 90 litres at an expenditure of water of 36 litres. In
this case the exit tube for the air, 5 mm. in diameter, is plunged 11 cm.
into the aquarium. If the tube is plunged lower, say 36 cm., the
pressure of the water which obstructs the exit of the air is greater,
and 45 litres of water would be expended in passing 16 litres of air,
i.e. 9 litres of water more, and 63 litres of air less. In the author’s
opinion, apart from the increase in the expenditure of water, it is un-
desirable that the air tube should go to the bottom of the aquarium, as
the disturbance to the water which is thus caused is unfavourable to
the development of delicate animals.
To ensure that the air-bubbles shall be small, the air tube is
terminated by a small sphere with half-a-dozen very small orifices at.
its equator, and enveloped with two or three thicknesses of muslin.
oun Te er
@ 3133 4)
PROCEEDINGS OF THE SOCIETY.
Meerrine or 147TH Decemser, 1881, ar Kine’s Cottecer, Stranp, W.C.,
Tue Presipent (Proressor P. Martin Duncan, F.R.S.) in THE
Cuatr.
The Minutes of the meeting of 9th November last were read and
confirmed, and were signed by the President.
The List of Donations (exclusive of exchanges and reprints)
received since the last meeting was submitted, and the thanks of the
Society given to the donor.
From
Micrographic Dictionary. 4thed. Parts4-6. .. .. .. Mr. Van Voorst.
Mr. Crisp exhibited Parkes’ Drawing-room Microscope with
magnetic stage, and two bottles from Professor H. Van Heurck, of
Antwerp, containing new fluids for use with homogeneous-immersion
lenses ; one (‘‘ liquide homogéne & la tacamaque”) with a refractive
index of 1:510, and a dispersive power of ‘0072, and the other (“a
Voliban) of the same index, but with a dispersive power of :0077.
Mr. John Mayall, jun., exhibited Mr. Deby’s method of turning
the correction-collar of objectives, the chief peculiarity of which was,
that the collar was worked by a tangent screw (with a long arm)
acting upon a worm-wheel, instead of by the ordinary collar-adjust-
ment, which Mr. Deby had found to be inconvenient (see p. 107). As
at present made, it would not go into an ordinary box, but (as had
been pointed out by Mr. Beck) the screw pinion might be con-
siderably shortened, so as to admit of its being put in a box in the
usual way.
Mr. Beck said that it must be borne in mind that in adjusting an
object-glass it was often desirable to get a sudden adjustment, which
could not be very well done with this form.
Mr. T. Charters White described, by means of black-board
drawings, a new form of growing or circulation slide which he had
recently devised, and exhibited the slide in action under a Microscope
see p. 19).
Mr. on Smith said he had been trying himself to work out
some better form of growing-slide than those in common use, but his
attempts had hitherto proved abortive. He was, however, very much
pleased with the one now shown by Mr. White, the great advantage
of which was its extreme simplicity, and its capability of keeping
objects alive for any length of time.
The President thought that its only disadvantage would be that
when carefully examining one particular individual, others might be
134 PROCEEDINGS OF THE SOCIETY.
introduced into the cell by the flowing water. With some kinds of
organisms there would, of course, be no such danger, but it would
hardly be safe with an Ameba, for instance. He had himself found,
when studying the life-history of minute species, that it answered
very well to make a small cell of ordinary thin glass, and by
surrounding the whole with blotting-paper, kept constantly wet, he
had been able to retain three or four monads of large size under con-
stant observation for several weeks. A similar arrangement to that
adopted by Mr. White had been used on the human body as a means
of applying evaporating lotions.
Mr. J. W. Stephenson said he had brought for exhibition some
scales of insects (Machilis maritimus and Tomocertus | Podura] plumbea),
mounted in phosphorus, and shown under a ;},-inch objective with
very oblique light and the binocular. They demonstrated that it was
possible even with such a high power to get with the binocular a
distinctly stereoscopic effect, and that when so seen a much more
perfect idea of the structure of the scale could be obtained than was
possible under the monocular. Although the structure of the scales
of Machilis maritimus and Tomocertus plumbea is probably the same,
they cannot be said to be “corrugated” in either case. In Machilis
the appearance of the upper side is that of longitudinal semi-cylin-
drical grooves, which had been likened by a medical gentleman to a
pill machine ; whilst the latter, probably from being so much smaller,
appears to have rectangular grooves, similar to those in a curry-comb,
the back being in each case supported by slender transverse bars,
which are approximately from one-third to one-half the distance
apart of the longitudinal divisions.
Mr. Beck said that as to the Podura scale shown by Mr. Stephen-
son, what he described with respect to the structure of the scales was
entirely opposed to what they had been shown to be. In such
matters where high powers and oblique light were used, he thought
it was very doubtful if they ought to believe what they saw, as they
might so very easily be deceived by appearances. So far as he knew,
no one had hitherto brought forward anything which would refute
what he had shown some years ago, when he put moisture on one side
of a scale, and found that it dried off quite flat, whilst if he put some
on the other side, it ran up and down as if in corrugations. His
brother also did the same kind of thing with a Lepisma scale and
Canada balsam. Moisture, as they knew, would get into slides which
were mounted dry, and the same appearances were presented there.
Having kept the insects, and being able to tell which was the upper,
and which the under side of the scale, and being also able to show
these corrugations in a mechanical way, he could only say that even
if the effect could be seen as described by Mr. Stephenson, he should
not, he was afraid, be convinced, for he knew very well that in most
cases, by reversing the shadows, they could reverse the appearances.
If they wanted to determine the real structure with high powers, they
must argue from analogy rather than from what theysaw. They had
compound substances to deal with, and effects were produced which
eis.
PROCEEDINGS OF THE SOCIETY. 135
had to be studied and analyzed and examined very carefully. Unless,
therefore, any one could show upon the upper side what he had shown
mechanically on the under side, he considered that the appearances
obtained by simple vision were deceptive.
Mr. Stewart said he understood that some time since a microtome
was made, so delicate in its adjustment as to be able to cut sections of
a valve of a diatom. Could not this be made available for making
sections of the scale which would show the configuration of it as
conclusively as if done in the mechanical way ?
Mr. Crisp said that the existence of such a microtome (cutting
150 consecutive sections of the brain of a cockroach) had been
reported, and he had endeavoured to obtain it, but hitherto in vain.
So far as he knew also, no results obtained from any actual sections
had been published, other than those which appeared in the ‘ Archiv
f. Mikr. Anat.’ in 1870. The further and more recent series pro-
mised by Dr. L. Flogel * had not been heard of.
Mr. Stephenson said that notwithstanding Mr. Beck’s remarks,
he could not but feel clear as to its being the upper side of the scale
on which these grooves were, for the pedicel or “quill” of the
“ feather,” which is necessarily on the under side of the scale, was
bent down from the plane of the scale, and the markings were clearly
on the opposite side to that.
Dr. John Anthony’s note was read by Mr. Stewart, suggesting
the statoblasts of Lophopus crystallinus as a test for high powers (see
p. 129). The difficult part was stated to be the structure of the mem-
brane. The portions of the statoblasts referred to were drawn on
the board and further explained by Mr. Stewart.
Mr. Guimaraens called attention to what appeared to be a male
specimen of the Hchinorhynchus of Lota vulgaris with ova in the
interior, described as “ dedans par hasard.”
Mr. A. D. Michael read a paper, “Further Notes on British
Oribatide ” (see p. 1), which Professor Huxley and others state to be
wholly viviparous. He found, however, that they are chiefly ovi-
parous, as stated by Nicolet and others, and that the young are
brought to maturity in, at least, four different modes :—1st. The egg is
deposited in a slightly advanced stage, as in insects. 2nd. Deposited
with the larva almost fully formed. 3rd. The female is occasionally
viviparous (in these modes only one egg is usually ripe at a time).
4th. Several eggs are matured at once, but not deposited. The mother
dies, the contents of her body, except the eggs, dry up, and her
chitinous exterior skeleton forms a protection throughout the winter
to the eggs. The occurrence of a deutovum stage in the egg is
recorded, i.e. the egg has a hard shell which splits into two halves
as the contents increase in volume, the lining membrane showing
between, and gradually becoming the true exterior envelope of the
* See this Journal, i. (1881) p. 509.
136 PROCEEDINGS OF THE SOCIETY.
egg. Several new and interesting species were described and figured,
and exhibited under Microscopes.
The President said he was very glad that Mr. Michael did not
form a new species from a single specimen. ‘The history of the
death of the parent insect before the escape of the ova was, he
thought, very anomalous in nature; indeed, he did not remember
anything at all like it. Many of the Lepidoptera died very soon after
the eggs were laid, but he knew of no case in which this remarkable
circumstance had been observed.
Mr. Stewart did not remember any in which the eggs were retained
in the body of the dead mother, but in the case of the Coccus there
was something, perhaps, a little like it, the mother dying immediately
after the deposition of the eggs, and forming a sort of roof over
them with her.dead body, which served to protect them during the
winter.
Mr. J. W. Stephenson exhibited Pleurosigma formosum mounted
in a solution of biniodide of mercury and iodide of potassium, a
mounting fluid which, with the exception of solution of phosphorus,
had a higher refractive index than anything known to him. It had
been used by Mr. Browning for prisms, and had an index of 1-68.
The index of bisulphide of carbon was 1°624, of monobromide of
naphthaline, 1-658, and of sulphur, 1°662, so that the biniodide of
mercury was *056 higher than bisulphide of carbon. Mr. Browning
found that the best means of sealing it was by using white wax. He
had brought some of it to the meeting as a sample. Being an aqueous
fluid appeared to be a great advantage, and it could be used of any
strength from 1°33 to 1°68.
The President said he had had his eyes opened to the value of
this solution as a highly refractive medium, but had been disappointed
by being told that it was only useful for purposes of spectrum analysis,
in consequence of the great effect which it had on the red rays.
Mr. Stephenson did not know how far its great dispersive power
would be prejudicial, but he had tried it for mounting, and found that
it did very well for diatoms.
Mr. Symons read a paper on “A Hot or Cold Stage for the
Microscope ” (see p. 21), the details of which were drawn upon the
board and the apparatus itself exhibited.
The President inquired if Mr. Symons had used this stage for
observing the motion of the white blood-corpuscles. He also
suggested that the brass would be better if it came rather more flush
with the plate.
Mr. Symons had not examined corpuscles with the stage, having
hitherto only applied it to ascertaining the melting-points of various
substances. He thought there would be no difficulty in using high
powers with it, as the objective could be brought into actual contact
with the glass if desired, the only thing between the plate and the
objective being the thin glass,
PROCEEDINGS OF THE SOCIETY. 137
The following Instruments, Objects, &c., were exhibited :—
Mr. Crisp :—Parkes’s “ Drawing-room” Microscope with magnetic
stage.
Mr. Deby:—New method of moving the correction-collar of
objectives (see p. 107).
Mr. Guimaraens :—Echinorhynchus of Lota vulgaris.
Mr. Michael :—Cepheus ocellatus n. sp. Nymph—showing the eye-
like appearance of the stigmata and stigmatic organs. Dameus
monilipes n. sp.—showing the tibiz of the first pair of legs. Leiosoma
palmacinctum—internymphal ecdysis showing arrangement of the
palmate hairs on new skin forming within present one. Notaspis
licnophorus n. sp.—showing the stigmatic organs.
Mr. Stephenson:—Scales of Machilis maritimus and Tomocertus
(Podura) plumbea, mounted in phosphorus under ;;-inch objective
- and binocular (see p. 184).
Mr. T. C. White:—New form of Growing or Circulation slide
(see p. 19).
New Fellows.—The following were elected Ordinary Fellows :—
Messrs. William Blackburn, Walter H. Coffin, F.L.S., F.C.S., the
Hon. William Nassau Jocelyn, and Theodore Wright.
CoNVERSAZIONE.
The first Conversazione of the Session was held on the 7th
December last in the Libraries of King’s College.
The following were the objects, &c., exhibited :—
Mr. C. Baker:
Stephenson’s Erecting Binocular Microscope for Laboratory use.
Homogeneous-immersion and Glycerine-immersion Objectives by
Gundlach and Zeiss.
Abbe’s Apertometer and Immersion Illuminator.
Dissecting Microscope by Zeiss.
Dr. Beale:
Muscular fibres of the bladder of Hyla.
Nerve-fibres of ditto.
Capillaries and nerve-fibres of the palate of the common frog.
Messrs. R. and J. Beck:
Pleurosigma angulatum with their new 4 object-glass.
Mr. W. A. Bevington:
Isthmia nervosa in situ.
Mr. W. G. Cocks:
Ophrydium and a remarkably large form of Epistylis.
Mr. J. E. Creese:
Radiolarian ooze from the ‘Challenger’ Expedition (2600
fathoms).
Mr. Crisp:
Colouring matter from willow-tree Aphides (Lachnus viminalis),
polarized, showing the characteristics of Salicine. Prepared
by Mr. C. J. Muller in illustration of his paper (ante, p. 39).
138 PROCEEDINGS OF THE SOCIETY.
Mr. T. Curties:
Schizonema Grevillet in situ.
Mr. L. Dreyfus:
Spirorbis nautiloides from a shell.
Professor P. M. Duncan :
Spheridia from a Spatangoid.
Cliona from a coral.
Mr. F. Enock:
Battledore fly (Mymar pulchellus).
Eyes of spider (Salticus tardigradus).
Mr. F. Fitch:
Dissection of blow-fly, showing abnormal condition of sucking
stomach.
Mr. C. J. Fox:
Various diffraction effects produced by rectilinear and circular
gratings.
Mr. D. W. Greenhough:
Crystals of asparagine.
Mr. J. F. Gibson :
Collection of seeds of British flowering plants.
Mr. W. H. Gilburt:
Section of Sporangium of Equisetum limosum, showing division of
nuclei in spore-mother-cells.
Dr. Heneage Gibbs:
Bacteria in kidney.
Mr. J. W. Groves:
Lymphatics in web of frog’s foot injected with silver nitrate.
Transverse section of stem of Smilax officinalis stained with
magenta, iodine green, and Nicholson’s blue.
Mr. A. de Souza Guimaraens :
Diplozoon paradoxum from carp.
Mr. H. F. Hailes:
Dactylopora and other Foraminifera from the Paris basin.
Mr. J. Hood:
Coccochloris cystifera and some Rotifers.
Messrs. Hopkin and Williams:
A large specimen of bichromate of potash crystals (14 lbs.).
Mr. J. Hunter:
Upper and lower jaw of cat, &c., with Polariscope.
Mr. J. E. Ingpen:
Illustrations of Professor Abbe’s diffraction experiments,
Mr. W. Joshua:
Desmids of many species from North Wales and other places.
Cidogonium Wolleanum Wittr. 8 insigne Nordst. Stromsberg,
Sweden. Ex Herb. Dr. Otto Nordstedt.
C. Wolleanum Wittr. in Rab. Alg. Eur. No. 2547. Exs. Wittr.
& Nordst. Alg. aq. dulce. exsic. fase. 3, No. 107. This
species has its place between C&. Borisianum (Le Cl.) Wittr.
and CE. concatenatum (Hass) Wittr., but is well distinguished
from both; among other things through the fact that the effect
PROCEEDINGS OF THE SOCIETY. 13Y
of the fecundation extends not only to the oosphere but also to
the wall of the oogonium. This wall increases in thickness
after the fecundation, receiving at the same time longitudinal
costz on its inner side.
Mr. A. D. Michael :
A new species of Hypopus.
Hremeus cymba, one of the rarest of the British Oribatide. ~
Dr. Matthews:
Corticium abyssi, and other sponges.
Dr. Millar :
Bacteria which convert nitrites into nitrates.
Mr. Millett :
A species of Acetabularia from the Lagunes near Cette.
Mr. E. M. Nelson:
Nobert’s 19th band (112,595 lines to the inch), with Powell
and Lealand’s oil-immersion +, (N.A. 1-428), and their vertical
illuminator (x 1000 diameters).
- Pleurosigma formosum, in balsam. Showing the sieve-like struc-
ture, with Zeiss’s DD (2) objective (N.A. °81), and direct
light from Powell and Lealand’s achromatic condenser (x 950
diameters).
Micrococcus in balsam, showing flagellum (length ;,),, of an
inch), with Powell and Lealand’s oil-immersion ,, (N.A.
1-237), and direct light with achromatic condenser (x 1250
diameters).
Lieut.-Colonel O’ Hara :
Crystals in poison of Bungarus ceruleus, an Indian snake.
New genus of Homoptera (Colydiide) from ant’s nest in India.
Messrs. Powell and Lealand :
Amphipleura pellucida in phosphorus, with an oil-immersion 1
(N.A. 1:47).
Mr. B. W. Priest:
Diastopora obelia.
Mr. §. O. Ridley : ;
Vertical sections of Halichondria panicea Johnston (Crumb-of-
bread Sponge), prepared by the method adopted by Professor
F. E. Schulze for Huplectella aspergillum (Trans. R. Soc. Edin-
burgh, xxix., ii., p. 661).
Mr, J. Smith:
Pleurosigma formosum and P. angulatum, with +1, immersion-
objective.
Mr. George Smith:
Dolerite from Liassic strata, Portrush, Co. Antrim, &e.
Mr. J. W. Stephenson :
Surirella gemma in phosphorus, with catoptric illuminator and
Zeiss’ homogeneous 4.
Mr. C. Stewart:
Water spider imbedded in the nacreous layer of an Anodon.
Young sole. :
140 PROCEEDINGS OF THE SOCIETY.
Mr. W. H. Symons :
Fatty acids melting and congealing on new hot and cold stage.
Mr. C. Tyler:
Hyalonema mirabilis, &c.
Mr. H. J. Waddington :
Pseudomorphs. Copper. Copper formate reduced by heat. The
resulting copper retaining the forms of the original crystals,
and analytic crystals of magnesium platino-cyanide polarized
with one prism.
Mr. F. H. Ward:
Section of stem of Nymphcea alba, Rosa canina, Eucalyptus globulus,
&c., double stained.
Mr. C. White:
Corethra plumicornis.
Pellets of Melicerta showing them to be apparently hollow.
Messrs. Watson & Sons:
Pleurosigma formosum with large angle }, and P. angulatum with
1 objective and Crossley’s swinging tail-piece Microscope.
Meetine or lltu Janvary, 1882, ar Krine’s Cottuce, Stranp, W.C.
Tur Presipent (Prov. P. Martin Duncay, F.R.S.) In THE CHarR.
The Minutes of the meeting of 14th December last were read
and confirmed, and were signed by the President.
The List of Donations (exclusive of exchanges and reprints)
received since the last meeting was submitted, and the thanks of the
Society given to the donors.
From
Davies, G. E.—Practical Microscopy, viii. and 335 pp.,
1 pl. and 257 figs. (8vo, London, 1882).. .. .._.. The Author.
Retzius, G—Das Gehororgan der Wirbelthiere. I. Das
Gehérorgan der Fische und Amphibien. 222 pp., 35 pls.
(Fol. Stockholm, 1881) ta ey EPR ee ee ne er Ditto.
Micrographic Dictionary, 4th ed., Part 7 ve ce ee) ge IM Vann Voonere
Eupodiscus argus mounted in gum-juniper.. = «. = «. 30s.) Mr. F, Kitton.
The President called the special attention of the meeting to Prof.
Retzius’ work as one of exceptional excellence, and constituting a very
handsome donation.
Mr. Badcock and Mr. Butler were appointed Auditors to audit
the Treasurer’s accounts.
The List of Fellows to be recommended to the Society for elec-.
tion as Members of the Council at the ensuing annual meeting in
February, was read in accordance with the 44th Bye-law.
The President gave notice that at the next meeting an altera-
tion would be proposed in the Bye-law relating to the payment of
PROCEEDINGS OF THE SOCIETY. 141
subscriptions, so that Fellows elected in any month after February
would only be called upon to pay a proportionate part of the sub-
scription.
Mr. Crisp exhibited Beck’s Miner’s Binocular Microscope, intended
for rough use in the field, and a photograph by Mr. Jennings of -001
erains of arsenic x 400.
Mr. Beck exhibited and described a new achromatic condenser
for dry and immersion objectives, with five different front lenses set
in a drum capable of being rotated consecutively over the back
combination, and giving apertures from 7° in air to 110° in glass
(1°25 N.A.). Mr. Beck stated that the mode of setting the front
lenses avoided the inconvenience of haying the immersion medium
drawn away by capillary attraction, as would be the case if the
lenses were mounted on a flat surface, as in previous forms.
Mr. Stewart exhibited and described a specimen of Gregarinide,
from the vesicule seminales of the earth-worm, and explained their
mode of growth and development, calling attention to the spines
frequently observed upon them, and which he inclined to believe were
bond fide cuticular appendages.
Mr. J. W. Stephenson read a paper “On Mounting Objects in
Phosphorus, and in a solution of biniodide of mercury and iodide
of potassium,” in which he explained in detail the methods which
he had found the most successful for the purpose.
Mr. Stewart thought that the biniodide would prove of very
great value as a mounting medium, on account of another of its
qualities not alluded to in the paper, namely, its chemical properties
as an antiseptic. He believed he was correct in saying that it
possessed the valuable power of preserving the colours of many
delicate vegetable tissues, and that chlorophyll was not changed by it ;
blues would be found to fade a little, but red was kept well, and he
thought that the fluid promised to be of great value in mounting such
organisms as desmids, the beauty of which was so greatly increased
by seeing them in their natural green colour.
The President said it occurred to him that these fluids might
be also of great use in enabling any one to see other difficult objects,
such, for instance, as coccoliths; they were very difficult to see in
the ordinary way, and he would suggest to Mr. Stephenson to try
whether they might not be made out more easily by means of such
media as he had described.
Mr. Crisp read a paper ‘“‘ On the conditions for Utilizing the Full
Aperture of Wide-angled Immersion Objectives.”
142 PROCEEDINGS OF THE SOCIETY.
Mr. Forrest's Compressorium (received 31st October last and
accidentally mislaid) was exhibited and described. It is designed
with a view to cheapness, and differs from the Wenham com-
pressorium in the action of the spring and screw being reversed, so
that instead of the spring putting on the pressure and the screw
releasing it, the screw puts the pressure on and the spring releases it.
It is claimed that this in practice will be found an advantage as it
enables the observer to feel what pressure is put on.
Mr. Crisp referred to the erroneous statements that had been
made as to the supposed advantages of Mauler’s blue glass slides in
“shortening the wave-lengths and so giving increased resolving
power.” The fact was that they were intended to be used with
objectives affected with chromatic aberration, the performance of
which was thereby greatly improved. A letter from M. Mauler was
read to the meeting, in which he mentioned that the blue mounts
would be found useful in the case of delicate histological preparations.
They also agreeably modified the ordinary yellow light of gas and oil
lamps.
Mr. Kitton’s note on the use of gum-juniper for mounting
diatoms was read. It has an index intermediate between water and
balsam, and is soluble in methylated spirit. Preparations may be at
once transferred from the spirit to the dissolved gum.
Dr. Anthony’s paper “On the Threads of Spiders’ Webs” was
read by Mr. Stewart, enlarged copies of the illustrations being drawn
upon the black-board.
The President said that Dr. Anthony had certainly exercised
great ingenuity in his methods of procedure. He believed that the
nature of the thread depended upon the spinnerets which were
used.
Mr. James Smith said that, in watching the process of an attack
by a spider upon a fly, he observed that, at the commencement, only
two or three spinnerets were used to spin the web round the fly. The
first portion of the web was like a quantity of floss silk, and then, as
the web converged towards the fly it became more like a gut-line.
After a while the fly began to struggle, and then the spider used some
more web, and finally used all-five spinnerets. He thought, from
what he had seen, that the quantity or quality of the web depended
upon what the spider wanted to use it for, and, according to this, he
used more or less of the spinnerets. ;
The President inquired whether Dr. Anthony should not have
used the word “she” in speaking of the spider. Was it not the
female spider which spun the webs ?
Mr. Stewart said he had often seen the male spider in the middle
of a web waiting for his prey, and always thought it was his own web,
for he certainly would not venture into the web of a female, knowing very
Sat *
PROCEEDINGS OF THE SOCIETY. 143
well what his fate would be. He believed that the explanation given
was quite correct, and that not only were the spinnerets of varied
form, but the glands inside them were different in structure so as
to be able to produce different kinds of threads. The cross threads, it
might be observed, contained an axis of comparatively hard, dry thread,
which was exceedingly elastic, and the outside portion was glutinous,
like birdlime, and remained so for years. If the thread was stretched this
would be seen to be the case; the gelatinous portion would break up
into beads.
Mr. Beck said that it was quite easy to examine the different
kinds of webs which were spun by a spider, and if they allowed the
spider to run out one of the glutinous threads, they could observe the
formation of the web and the globules. He had had frequently to
_use spiders’ webs for the cross-lines of transit instruments, for
instance, and the kind used were not at all adhesive. Any one who
had watched a spider encasing his prey would have noticed how
entirely the web seemed to be under command, and that there appeared
to be a remarkable power of changing the character of the web at will.
The spinning-organs were very highly developed and would form a
very good subject for a monograph.
Mr. Crisp referred to the researches of the Rev. H.C. McCook on
spiders’ webs.*
Dr. Matthews inquired how it was that the spider dropped or
divided his web without using his jaws, and how it was that he climbed
up his web, if it was composed of glutinous threads ?
Mr. Beck said that a spider did not always use glutinous threads.
The radial lines of the web were not glutinous; neither were those
which were used to tie the web fast to neighbouring objects; but only
the transverse lines.
Mr. Michael said that any one who watched a spider, would see
that he took great care not to put his foot on the transverse lines of
his web; but that in running across it he always walked on the radial
lines only.
Mr. Crisp said that in a letter to Mr. Mayall, Dr. Anthony had
anticipated Dr. Matthews’ query as to the division of the web, and
proposed to show in a further communication on the spinnerets that
the spider did not use his jaws for the purpose, but that there was a
special apparatus at the end of the spinnerets. The diagram accom-
panying the letter illustrating this apparatus was enlarged upon the
black-board by Mr. Stewart.
Mr. Badcock said he had brought some specimens of Lophopus
erystallinus to show what might be found in the depth of winter, A
pond in Epping Forest a few days ago had what looked like a mass
of fungi in the middle of it,and on examination it turned out to be an
immense quantity of Polyzoa. He thought that naturalists often
failed to find things because they did not look for them in the winter.
* See this Journal, ii. (1879) p. 559, and Proce. Acad. Nat. Sci. Phila. 1881.
144 PROCEEDINGS OF THE SOCIETY.
The pond in question contained nothing of any consequence in the
summer.
Mr. Stewart said that the specimen exhibited by Mr. Badcock was
the finest he had ever seen. .
The following Instruments, Objects, &c., were exhibited :—
Mr. Badcock :—Lophopus crystallinus.
Messrs. Beck :—New Condenser (see p. 141).
Mr. Crisp :—(1) Beck’s Miner’s Binocular Microscope. (2) Photo-
graph by Mr. Jennings of +001 grain of arsenic x 400. (3) Mauler’s
blue glass slides.
Mr. Forrest :—New Compressorium.
Dr. Gibbes:—(1) Bacillus anthracis in lung. (2) Section of
tongue treble stained and injected.
Mr. Kitton :—Eupodiscus argus mounted in gum-juniper.
Mr. Stephenson :—Specimens illustrating his paper on mounting.
Mr. Stewart :—Gregarinide from vesicule seminales of the earth-
worm.
New Fellows.—The following were elected Ordinary Fellows :—
Messrs. W. J. Abel, Herbert C. Chadwick, Walter H. Mead, and
James Warnock.
—
ee
The Journal is issued on the second Wednesday of
February, April, June, August, October, and December.
: Sizer Ser 8
Ser, II. ‘ APRIL. 1882 To Non-Fellows, HG
Vol. II. Part 2. } : { Price 4s.
= |
= JOURNAL
ROYAL ee
MICROSCOPICAL SOCIETY;
CONTAINING ITS TRANSACTIONS AND PROCEEDINGS,
-‘ AND A SUMMARY OF CURRENT RESEARCHES RELATING TO
ZOOLOGY AND BOTANY
(principally Invertebrata and Cryptogamia),
MICROSCOPY, &c-
Edited by
FRANK CRISP, LL.B., B.A.,
One of the Secretaries of the Society
ae a Vice-President and Treasurer of the Linnean Society of London. ;
WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND
x A. W. BENNETT, M.A., B.Sc., -E, JEFFREY BELL, M.A,,
~ Lecturer on arany at St. T, iim Ss Hospital, Professor of C omparative Anatomy in King’s College,
{
|
8. 0. PABEEN, MLA, of the British Museum, aND JOHN MAYALL, Jon.,
/
.
|
FELLOWS OF THE SOCIETY,
“WILLIAMS & NORGATE, =
LONDON AND EDINBURGH. )
y
15
WM. CLOWES AND SONS, LIMITED,] s [STAMFORD STREET AND CHARING CROSS.
Cra ioe
JOURNAL
OF THE
ROYAL MICROSCOPICAL SOCIETY. —
Ser. 2.-Vot. Il. PART-2. .S
(APRIL, 1882.) .
CONTENTS.
_—o;00—— : ; :
TRANSACTIONS OF THE SocraTy— eee
IV.—Tue Presrpent’s Appress. By Prof. P. Martin Duncan, M.B.
Lond ERs M026 ee. as saad
V.—On Movntine Ossects In PHospHorvs, AND IN A SoLuTion oF.
Braropipr or Mercury AnD Iopipr or Porasstum. By John
Ware Stephenson, Vice-President R.M.S., P.R.AS. 3. 5,
VL—Ow tae Tareaps or Sprpers’ Wess. By John Anthony, MD.
E.R.MS., &e. oe ee ae ee ee ey we oe CY ed 7 f
Summary or Current RaseaRcHEs RELATING TO ZooLoGy AND
Borany (PRINCIPALLY INVERTEBRATA AND CryProgamia), Mioro- —
soory, &c., INCLUDING ORIGINAL COMMUNICATIONS FROM FELLows. a
AMD ORHERS 2505 9 C0 rls oe oe ps me ee
: - ZooLoay. —
Germinal Layers and Early Development of the Mole .. +1 v1 +e ne
Development of Amphioxus a ae Che oes anes ;
Fossil Organisms in Meteorites .. +. ++
Red Pigment of Invertebrates (Tetronerythrine) +. «+ + ;
Maturation, Fecundation and Segmentation of Limax campestris. +. +
Kidney of Chiton Be ie eee cera LUNGS ob ee
Morphology of Neomenta «1 5 ose ae ee ae te
Organization and Development of the Ascidians .. ++ +
ee oe oe o* can ;'
oe ee of oe (aie
of
. oo ee oe
-* Pe ae
“ Challenger” Ascidians (Culeolus) Seen
Embryonic Membranes of the Sulpide ~.. +. + see
Modifications of the Avicularia in Bryozoa «+ ++ ++ ee ow
Blight of Insects 2. 050 See ee ae a oe ae
Nucleus of the Salivary Cells of the Larvx of Chironomus .. .._
ee) Structure of the Dermaleichide .. 1. 2 ee ey ne pee
- New and rare French Crustacea (Fig. 28) ++ ee ee ee
- New British Cladocera from Grasmere Lake... .. ++ +4
The Entoniscida 00 3 ant toe oe ae ee Oo
Phe Bopyridse 2255 6B. hey eno be 5 AR pk oe a ae ae ;
- Anatomy and Histology of Scoloplos armiger + s+ we ew
Parasitic Eunicid .. ee ee on :
~~ Development of Anguillula stercoralis, +. 4 tem we we es
_Cercuria with Caudal Sete 0 ee ee te ae ne
“New Type of Turbellaria 2.00 se weoc ee ee eee ee
- Systematic Position of Balanoglossus 5) «+s ve 4
| Nervous System of Platyhelminthes .. +1 +5 ++ ee ae
Structure of Gunda seqmentata, and the Relationships of the Plat
with the Coelenterata and Hirudinea © ss se oe. we
Nervous System of the Ophiuroidea .. 1. ve ee ty ve
American. Comatulee 92) 24. se oak ne) nes de a ae
Characters of Stinging-cells of Coelenterata 1. +1 i) +s wn
(ey:
Summary or Current Resmancuss, &e.—continued.
Development of the Celenterata.. .. +s +» oe ee
Nervous System of Hydroid Polyps ..- .. «+ ss oes
Remarkable Organ in Eudendrium ramoswin .. sae ss
Siphonophora of the Bay of Naples... .. 2+ + +s
Ctenophora of the Bay of Naples
Symbiosis of Lower Animals with Planis.— Yellow Cells of Radiolarians
and Celenterates.. .. Be Seb
New sub-class of Infusoria—(Pulsatoria). AACR TRL ee
Skeleton of the Radiolaria .. 1. .. an we tee we
Recent. Researches on the Helga iota ee
Dimorpha mutans.»
Contributions to the Knowledge of th the Amba (Plate TL) 3)
Protozoa of the White Sea... -. Bee Cisse led fs abe ee
BorTany.
Free Cell-formation in the Embryo-sac of ree aed
Structure and Division of the Vegetable Cell. ais
Fertilization of Apocynacez .. Mee ee
Cross-fertilization and Distribution of Seeds .
Swelling of the-Pe@ <0 ie cee ee Nay) aw oe ee ae
Aril of Ravenala.. . ASAP NSE? oer bon wrth Arc
Structure and Mechanics of ‘Stomata EEE REE Deen Er
Callus-plates of Steve-tubes Sere bok eee iiwae te
Phyllomice Nectar Glands in Poplars BED rh erat caine
Histology of Urticacez A
Structure of Podostemonacez «ss. ss ae we ote
Pitchers of Cephalotus follicularis .. 2. se +0 +5 =
Action of Light on Vegetation .. oP
Production of Heat by Intramolecular Respiration. Ngee ae
Physiological Functions of Baia le a sacle
Metastasis .. .. Pacer t ats beer eee
Phosphorescence in Plants. CA PACE, Oe erty
Transformation of Starch .
Occurrence of Allantoin in the Vegetable Organism
Ezcretion of Water on the Surface of Nectaries ..
«8 (ee
ee
e
Determination of the Aciaty. of Assimilation by the Bubbles given
under water... -. PE EN eA ter aap eens
| Detmer’s Vegetable Physiology... .. sc sw ss wee
Development of Sporangia.. .. ss «2 se e eines
Lenticels of the Marattiacer _.. Bie Caper Rae eer
Stomata in the Leaf-stalk: of Filiciner |.
_ Adventitious Buds.on the Lamina of the Frond of Asplenivm bulbiferum 5
. - Anatomy and Classification of Schizwace@ 1. .» se
-. Biological peculiarity of Azolla carolintana ., +. «sss
Female Receptacle of the Jungermanniez Geocalycex .. +
Vegetative Reproduction of Sphagnum 0.5 ss ee on os
_ Action of Light on Fung iomt saan ap
Chemical Nature of the the Cell-awall in “Fungi Svar Ueceel oes
“ Mal nero” of the Vine... . Sirah ie Boies ges Ap
Roesleria hypogzxa parasitic on the Vine een ee hee
eta Didymosphzria and Microthelia .. 4. eos bg
Peronosporer and. Saprolegniee 10 ss an nee
. Fungi in Pharmaceutical Solutions .. .. oe be ie
Vegetable Organisms in Human Excrements s+ we 0s
Saccharomyces apiculatus .. 0 16, cee ee ne ee
| Etiology of Malarial Fevers .. SS awit pace eres
-. Aktinomykosis, a new Fungoid Catile-Disease Fea aes ee
Infection by Symptomatic Anthraz .. ie
. Experiments on Pasteur’s Method of Anthrax-Vaccination ..
Duration of Immunity from Anthraz — -s we we ee
Sip pe Method of Vaccination for Foul-cholera, gt ee eek
oe. ve oe oe o*
.
“Nutrition of Lichens .... PIR ig Bah Aas Ma
- .. Thallus of Usnea articulata .. 2
Tanta at aetin of. Lower Animals with Plants”
os
°°
oe
ee
oe
Ook,
Summary or Current Ruszarnouss, &c.—continued.
* Yellow Cells” of Radiolarians and eigite ny et Sok Gab. 1 toe eee
Cooke’s British Fresh-water Algz .. .«- Te UB ae ys:
Diatoms in thin Rock Sections .. RM ANN 7
Fineness of Striation as a Specific Character of Diatoms sie
Schmidt's Atlas of the Diatomacex .. +. APES EP aR
““ Aphaneri” —Ezamination of Water .. «+ «+ en te eee aw
Microscopy. : 2
oi Aope ” Class Microscope (Fig. 29) Bd Sf ATT Se aoe aa
Brownings Portable Microscope (Figs. 30 ‘and '31)-
Harting’s Binocular Microscope (Figs. 32 and 33) ays, pea eR RT a
Nachet’s Double-bodied Mieroscope-tube (Figs, 34 and 3 Sas “955 4
Wenham’s Universal Inclining and Rotating Microscope (Plate Iv ) igs a ae
36-39) . 25
Bausch and Lomb Optical Co? 8 : Trichinoscope (Figs. 40 and 41). ge: a
“ Hampden” Portable Simple Microscope (Figs. 42 and 43) BRN Fan ert.
Excluding Extraneous Light from the Microscope... .. «+ + ## es ‘
Nachet’s Improved Camera Lucida (Figs. 44-46) wa’ = sav schon a Rie
Abbe’s Camera Lucida (Fig. 47) Be eae Pi Mom etm ace 1}
Curtis’s Camera Lucida Drawing Arrangement SS i Sc eae ge ee
Drawing on Gelatine with the Camera Lucida «. oo, 262%
Tris-Diaphragm for varying the Aperture of Objectives (Figs. 48 ‘and 49). oa ee
Gundlach 4-inch Objective... .. Brice eed
Scratching the Front Lenses of Homogencous-immersion Onjctives Fe the
Fluids for Homogeneous Immersion... .. S5IN each owas Sage
Advantage of Homogeneous Immersion se os iy iter Seam h nee
Vertical Illuminator for examining Histological Elements oa tet weet ae,
Grifith’s Parabolic Reflector .. +e +4 + SPRL Ag 7 2
Forrest’s Compressorium (Fig. 50). Wi tea peek as
Julien’s Stage Heating Apparatus (Figs. 51 and 52) 7
Beck’s Achromatic Condenser for Dry ot Immersion Onjectivs Gigs, 53.
and 54).. ee we
Pennock’s Oblique ‘Diaphragm (Fig. 55)
Stereoscopic Vision with Non- -etereoscopic Binocular Areongeuiente (Figs. a
56-58) . eB SS hae ee ee ama
Injection of Thvertebrate ipa C2 LES SO Ae, arenas
Cold Injection Mass .. +. BAT ete AORN Lire so ae
Staining with Saffranin .. Bocce ae CNS oy 0 ie ee
Staining with Silver Nitrate .. PRR SE ar pW aN et ty GSN TE a SP.
Staining Tissues treated with Osmic NAotd © ace eee a ee Se
Mounting the «‘ Saw” of the sda kink aca SAG ie winhn nse oleh, see iene ‘3
= Mounting Butterfly-scales .. .. CP gh te ae en a
Imbedding Ctenophora _.. PROMABr MEL We keerse sin oc
Staining Living Protoplasm with Bitmarck Brown... ad heat Se
' Preservation of Infusoria and other Microscopical Organisms Sash gpa teen
Staining the Nucleus of Infusoria .. 1. 16 ne te te eee ge
Aniline Dyes and Vegetable Tissues .. vo) laser Aiea” [oe hte Figeree
Indol as a reagent for Lignified Pultmenbiens bone ext
- English’s Method of Preserving Hoorn and Wild Flowers pe
- Mounting Salicine Crystals _.. per, sae Ne Bel
_ Bausch and Lomb Turntable (Fig. 59) . AG igh Sigh ek ae age
Griffith Cell. pole intew Nee. Ar pene, f Vx hie Lg sie ti
Bausch and Lomb Circle Cutter (Fig. 60) Fe Ce Af Negras
Wax and Guttapercha in Dry Mounting... 2. +s ee ee
Aeration of Aquaria “ oo ee ee se rs - se ee Tepe
PROCEEDINGS OF THE Soomry Pe aeee ct ae alee a We ene eae
Treasurer's:Account. §< 4,0 avi ee Se ae Oe ae
Report of the Council ©... ee 2
C53
Royal Atlicroscopical Society.
, MEBTINGS FOR 1882,
At 8 P.M.
1882. Weditcdday; JANUARY << 1650 ' re. auch bce AL
FPRBRUARY ... . é P 8
(Annual Meeting for Election - ise
and Council.)
>) ae
WEG or Se a a ie See ay cate eo
PRPTNG Sie he Be Aas Sag ae ce mia olen EO
DER eng iol pas ac Re Soa tak Aa
PUNK Sy cece ee Pe ee a ene AAS
es OCTOBRE 0 os sieht aier a ge eg AL
» Novemsrr SPE EEN ee ER les 7
DECEMBER ae spi WS in Uae eee ap ke
"THE “ SOCIETY » STANDARD SCREW.
a ‘The Council lave made arrangements for a fatihice scans of Gauges -
and | Serew-tvols for the “ ‘Socrery ” STANDARD Screw for OBJECTIVES.
ic The price of the set (eousiatins of Gauge and pair of Screw-tools) is
12s 8. 6d. (post free 12s. 10d.). Hpplications. for sets should be made to the
istant-Secretary. cp
es For an ‘explanation of the intended use of the ginge, see i onal ie the —
8 ay} ee PP. 548-9. . |
a
= a :
a, Tp ed
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; Pes ‘
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COUNCIL.
ELECTED 8th FEBRUARY, 1882.
PRESIDENT.
Pror. P. Martin Dunoan, M.B., F.R.S.
VICE-PRESIDENTS.
Pror. F. M. Batrour, M.A,, F.R.S.
Rosert Brarrawairs, Esq., M.D., M.B.C.S., F.L. Ss.
Rosert Hopson, Esq., F.RS., F.LS.
JoHN Ware Srepuenson, Hsq., F,R.AS.
ee Sat RRC eg is Se eae tee a NG Oe 5g ati ¢ aA
OTL Mae SR Ne ER EET BT Cee Pet Mant YAO, ETE ee RIN oe SY Cig
TREASURER.
Lions 8. Bratz, Esq., MB, FRCP. ERS.
SECRETARIES.
‘Caarres Srawarr, Esq, MLB.CS., F.LS.
Frank Crisp, Esq., LL.B, BA, V.P. & Treas. LS.
Twelve other MEMBERS of COUNCIL.
Lupwie Dreyros, Esq.
Cuartes James Fox, Esq.
James Guaisner, Hsq., F.RS., F.RAS.
J. Wiut1m Groves, Esq.
A. pe Souza GUIMARAENS, Esq.
Joun E, Inapen, Esq.
Joun Mayatn, Esq., Jun.
Ausert D. Micmarn, Esq., F.LS,
Joux Miran, Esq., L.R.0.P.Edin., FLS.
Wit11am Tuomas Surroux, Esq.
Freperiox H. Warp, Esq., M.R.CS. -
a CaanTErs ee mie MRCS, ALS.
OE fee)
I. Numerical Aperture Table.
“ ApgRTURE” of an optical instrument indicates its greater or less capacity for receiving rays from the object and
transmitting them to the image, and the aperture of a Microscope objective is therefore determined by. the ratio
between its focal length and the diameter of the emergent pencil at the plane of its emergence—that is, the utilized
“diameter of a single-lens objective or of the back lens of a compound objective.
his ratio is expressed for all media and in all cases by m sin wu, m being the refractive index of the medium and w the
mi-angle of aperture. The value of m sin u for any particular case is the ‘numerical aperture” of the objective,
Angle of Aperture (=2 1). Theoretical P
Iw ical Ilumi-| Resolving |; hg
Dry and Immersion mneriica Water- | Homogeneous-| nating Power, in TRUDE,
bjectives of the same Gh ae i bare Okie. Immersion| Immersion | Power. | Lines to an Inch,| FOWe
___ Power G in.) Hi hyp OBI ives: | Objectives,| Objectives. | (a2.) | (A=0°5269y (2 )
m.0°50 to 1-52 N. A. @=1) \m= 1:23.) (nm = 1°52.) =line E.) a
oe a 180° 0’ |2°310) 146,528 "658
me 161° 23’ |2°250|. 144,600 *667
153° 89’ |2°190| 142,672 “676
Z 147° 42’ |2-132| 140,744 “685
a 142° 40’ 138,816 694
fe 138° 12! | 136,888 “704
as 134° 10’ 134,960 -714
ew 130° 26’ 133, 032 725
126° 57’ | 131,104 “735
123° 40’ 129,176 -746
180° 0’|}. 122° @’
on 165° 56’| 120° 33’
EP 155° 38’) 117° 34’
ce 148° 28’| 114° 44’
oh 142° 39’| 111° 59’
oe 137° 36’; 109° 20’
se 133° 4’| 106° 45’
ae 128° 55'| 104° 15’
074
016
960
904
850
796
770; 128,212 "752
742 | 127,248 "758
-690| 125,320 *769
638
588
538
488
440
392
346
300
123,392 | °781
121,464 | «794
119,536 | 806
117,608 | +820
115,680 | °833
113,752 | °847
111,824 | +862
109,896 | 877
-254| 107,968 | °893
-210| 106,040 | +909
166} 104,112 | -926
-124| 102,184 | -943
! 082} 100,256 | -962
y 100° 10'/| 84° 18’ |1-:040| 98,328 | ~-980
180° 0’ | 97° 31’) 82°17" |1:000| 96,400 | 1-000
157° 2 | 94° 56/| 80° 17'| -960| 94,472 | 1-020 ~
147° 99' | 92° 24’! 78° 20'| +922) 92,544 | 1-042
140° 6’ | 89° 56’) 76° 24’ | +884) 90,616 | 1-064
133° 51’ | 87° 32’| 74° 30’| -846| 88,688 | 1-087
128° 19'| 85° 10’) 72° 36’| +810} 86,760 | 1-111
123° 17'| 92° 51’| 70° 44’ | -774| 84,832 | 1-136
118° 38’| 80° 34’) 68° 54’ | °740| 82,904 | 1-163
114° 17’| 78° 20’, 67° 6'| +706} 80,976 | 1-190
“110° 10’ | 76° 8'| 65° 18’ | *672| 79,048 | 1°220
106° 16' | 73° 58’| 63° 31’ | °640| 77,120 | 1-250
402° 31’ | 71° 49'| 61° 45' | 608} 75,192 | 1-282
9g° 56'| 69° 42’, 60° 0/| -578| 73,264 | 1-316
95° 99° | 67° 36'| 58° 16" | -548| . 71,336 | 1-351
92° 6’ |. 65° 32} 56° 32’ | -518| 69,408 | 1-389
-gg° 51" | 68° 31’| 54° 50’ | +490) 67,480. | 1-429
85° 41’ | 61° 30’| 53° 9’ | -462| 65,552 | 1-471
92° 36 | 59° 30'|. 519-28’ | -436| 63,624 | 1-515
79° 35' | 57° 81'| 49° 48" | -410| 61,696 | 1°562
76° 38’ | 55° 34’| 48° 9" | +884) 59,768 | 1-613
73° 44’ | 58° 38’| 46° 30'| °360| 57,840 | 1-667
"70° 54’ | 51° 42"| 44° 51’ | +336) 55,912 | 1-724
68° 6’ | 49° 48’). 43° 14" | «314| 53,984 | 1-786
65° 22' | 47° 54’! 41° 87" | +292) ~ 52,056 | 1-852
62° 40' | 46° 2| 40° 0'| -270; 50,128 | 1-923
60° 0’ | 44° 10’| 38° 24’ | -250/ 48,200 | 2-000
Oe oak ee
COPADOCW HAD OW HADOWHADOWHADOWHADOOHAMOWHKADOWVWHADOW
w. . }125°° 8" ¥01° 50°
.. [121° 26'| 99° 29°
EO TIBS 00!) O72 AL
.- | 114° 44’) 94° 56"
.» | 111° 86’| 92° 43°
_|108° 36} 90° 33’
{105° 42’| 88° 26'
wo |109°-53’| 86° 21’
°
AAAAADHADDOAIAIIIAIDHDHHDDOHOOOSOOSOOH EH ERD
Pe tet pe ede ke ek ek et et et et et et et et et BODO EO DO
Ty ER APRN SRR Ta EN SEEDY AAS IBLE pas
SECTS (oie al ole sich tale unless eirkenirek nininanl Crane ena
2009900000006
PLE.—The apertures: of four
ould be compared on the angular aperture view as follows:—106° (air), 157° (air), 14
‘actual apertures are, however,.as ; ‘ len «3 eth}: Stuy nape
“tiumerical apertures, § =! ;
objectives, two of which are dry, one water-immersion, and one oil-immersion,
2° (water), 130° (oil).
26. ~-.» 1°38 or their
CA?
II. Conversion of British and Metric Measures.
1.) LinkAL.
Scale showing Micromillimetres, §c., into Inches, fc,
y Peta “ ins. mm. ins. | mm. ins.
&c., to Inches. 1 :000039| 4 -039370| 51 2007892
?
“ine 2 -000079| 2 “078741 4 pe
3 000118| 38 118111 08663:
Pe ats. 4 -000157| 4 -157482| 54 2- 126008
5 :000197| 5 “196852 | 55 2: 165374
= at] 6 -000236| 6 “236223 | 56 2204744
ae 7 -000276|° 7 275593 | 5'7 2°244115
= ml 8 +000315| 8 -314963 | 58 2+283485
le | 9 +000354| 9. “354334 | 59 2- 329855
aoe | 10 -000394! 10(1cm.) -393704| 60 (6cm.) 2°362226
E z| 11 -000483| 11 | 433075) 61 2°401596
A 000472 - 472445 ag meet
el 3 +000512 ‘511816 480337
= 8
=f 14 -000551| 14 “551186 | 64 2+519708
Be 15 -000591| 15 -590556 | 65 2°559078
jeu 16 -000630| 16 “629927 | 66 2°598449
Rie 8 17 -000669| 17 “669297 | 67 2637819
is s| 18 000709 i “708668 ae 2077188
=e 19 000748 *748038 “71656
lz H| 20 +000787| 20 (2em.) +787409| 70 (7em.) 2-755930
Jes 21 -000827| 21 ‘826779 | ‘71 2°795801
E zl 22 “000866 | 22 “866150 ie gener
=m -000906 | 23 -905520 2874042.
iE z| 24 000945 24 “944890 74 2-913412
=5 5 000984 | 25. -984261 2+952782
=e 26 -001024| 26 1023631 | 76 - 2°992153
lz 3 27 -001063 | 27 1:063002| 77 3°031523
BS 28 -001102| 28 1:102372| 78 - 8:070894 fe
el 29 -001142| 29 1°141743| 79 3:110264 as
Es 30 +001181| 80 (80m,)1:181113| 80 (Sem) 3:149635, Aj.
Ee 31 -001220| 31 1:220483| 81 3°189005 | ve
=a 32 -001260| 32 1°259854 | 82 3:228375 |. as 1
E | 33 *001299| 33 1°299224 | 83 3°267746 | tz. 2!
aS 34 :001339 | 34 1:338595 | 84 3°307116| we 72%
[ze 35. 001878 | 35 1°377965 | 85 3346487] «OE
= 86 -001417| 86 1:417336 | 86 3°385857 2 ae
[Em 37 :001457| 37 1°456706| 87 3°425298 | oats =
=e 838 001496 | 38 1:496076 | 88 3°464598 |. $970
jes 39 -001535| 39 1°535447 | 89 3:503968| + 6°34
cE | 40 -001575| 40 (4om.)1:574817| 90.(9cm.) 3:543389] ae 7
=m 41 -:001614| 41 . 1°614188| 91 RRP AL ISR api ag I os
Pe 2 42 -001654| 42 1°653558 | 92 3°622080|. i» 1,
=5 43 -001693| 48 1-692929 | 98 3°661450 | x
Es 44 +001732| 44 1°732299 | 94 3*700820} 2.
WEE 45 -001772| 45 1°771669 | 95 3740191 |
| (Be 46 001811} 46 1°811040| 96 3°779561| 1
ze 47 -001850| 47 -1°850410| 97 3°8189382| 3s
= |. 48 +001890| 48- 1889781 | 98 _ 8858302}
lz | 49 +001929| 49 1:929151' 99. 3-897673 |.
s8 5O +001969 | 50 (5em.)1:968522 1100 (10 om,=1 decim.)|
[El 60 -002362 n eee ie ef
[E + 70 002756 decim. Te eA
SE 80 -003150 1 ~ 8+937043
lee 90 003543 2 - 1+874086
| 100 = -003937 3 11°811130 ©
[zs 200 007874 al 15+748173
=n 800 -011811 5 19°685216
[zs 400 +015748 536 ~ 93-622259
500 -019685 "7 277559302
Bee 600. -023622 8 31496346
10002 =1mm, 700 -027559 | 9 35-483389
10 mm.=1 em. 800 -:031496 10 (1 metre). $9°370432
10cm. =1dm, | 900 *035438 = 3-280869 ft.
10 dm. =1 metre. | 1000 (=1 mm.) ' a = 1093623 yds,
*SOTMUIBIDOTTY
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are inserted between them. A simple Microscope can be moved in
different directions across the apertures in the plates so as to com-
mand a view of every part. It is focussed by being screwed up and
down in the socket at the end of the arm which carries it.
Fra. 41.
Wt! nT
A thin slice of flesh having been moistened with a mixture of
equal parts of acetic acid and glycerine, is put on the lower glass plate
and spread out by needles or a brush, the second plate is brought
down upon the lower one and the screw is placed in the slot into which
it fits. By turning the screw any degree of pressure may be brought to
bear on the flesh, which may thus be rendered so thin and transparent
that any trichine present will be readily visible when the Trichino-
scope is held up between the eye and light.
““Hampden”’ Portable Simple Microscope.—This instrument
(Figs. 42 and 43) is made by Messrs. Beck and is the device of the
wife of a distinguished English statesman now ruling in India. It
combines, with great portability, very convenient arrangements for the
* Amer. Jour. Micr., vi. (1881) pp, 183-5 (3 figs.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 259
most effective use of a dissecting lens or simple Microscope in the
field or when travelling.
The lens, stage, and mirror are each carried by a bar sliding on
the upright stem which screws into the circular foot. The bars can be
Fic. 43.
ru li
————
adjusted to any height and secured by the screws, of which the milled
heads are shown on the right of Fig. 42. When detached the instru-
$2
260 SUMMARY OF OURRENT RESEARCHES RELATING TO
ment packs very conveniently into asmall case 54in. x 23in. x 1} in.
in the manner shown in Fig. 48, and is then readily carried in the pocket.
Sir John Lubbock, who has on several botanical excursions taken
the instrument with him, speaks highly of its usefulness.
Excluding Extraneous Light from the Microscope.*—In order to
exclude light of an injurious character, whether falling laterally on the
eye of the observer or on the stage from above, T. W. Engelmann places
the Microscope in a dark box, made portable, and admitting the light
through a funnel-shaped opening in the broad front side. The body
of the observer as well as the Microscope and its belongings are
intended to be included in the box, which is 75 em. high, 80 em.
broad, and 40 cm. deep, and is arranged so as to carry accessory
apparatus, reagents, coloured glass plates, &c.
Nachet’s Improved Camera Lucida.—In its original form this
camera lucida consisted of a rhomboidal prism A B C D, placed
over the eye-piece of the Microscope, as shown in Fig. 44, and having
cemented to the face A C a seg-
Fic. 44. ment of a small glass cylinder H,
the ray ab from the eye-piece
and that (a’ b’) from the pencil
meeting the eye at b.
The disadvantage of this
form was that the eye must be
held very steadily just over the
glass cylinder E (the function
of which was to allow the rays
from the object to pass to the
eye-piece without refraction), to
obviate which M. Nachet has
made use of a suggestion of
Professor G. Govi, and deposits a thin film of gold on the face
AC of the prism (Fig. 45). The gold reflects the ray a’ b' to b as
Fia. 45. Fic. 46.
before; whilst, at the same time, on account of its translucency, it
allows the ray a to pass through it from the eye-piece. The small
* Pfliiger’s Archiy ges. Physiol., xxiii. (1880) p. 571.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 261
prism E is replaced by a larger one, H’, cemented upon the gold film
(protecting it also from being rubbed off), and a slight inclination is
given to the under surface at D’, in order to avoid too great an
approximation of the pencil to the foot of the Microscope.
The image of the paper is tinted yellow by the rays reflected from
the surface of the gold, while that of the object’ is of an emerald
green tint, that being the colour given to the rays in passing through
gold. 5
Fig. 46 shows the camera lucida in place over the eye-piece.
Abbe’s Camera Lucida.*—Dr. L. Dippel commends the following
as an extremely simple and complete apparatus for drawing on a
horizontal surface.
A small glass cube A (Fig. 47) composed of two right-angled
prisms cemented together is placed over the eye-piece C, one of the
prisms having an hypothenuse surface silvered, leaving, however, a
Fic. 47.
S =)
circular hole. The cube is so adjusted that the hole exactly coin-
cides with the “ eye-point” of a Zeiss No. 2 ocular(C). The mirror
B is connected with the fastening of A by an arm about 70 mm. from
the axis of the Microscope.
In use, the instrument is fastened to the eye-piece cover by two
centering screws, and the mirror so turned that the surface of the
table close beside the foot of the Microscope appears to be projected
on the circular field of the eye-piece. The whole field of view is now
readily seen, and with uniform sharpness, and this is the case also
when the higher powers are used, no perceptible loss of light taking
place in the vision of the microscopical image. One of the most
essential qualities of a good camera lucida is therefore obtained.
That the camera is attached to a particular eye-piece, and is not,
as usual, made adjustable for those of different power, arises from the
fact that in the higher Huyghenian eye-pieces the eye-point lies too
near the eye-lens.
* Bot. Centralbl., ix. (1882) pp. 242-3 (1 fig.).
262 SUMMARY OF CURRENT RESEARCHES RELATING TO
Dr. Dippel says that he has thoroughly tested the camera with
very delicate drawings, and has found it of excellent service, and
he considers it is to be preferred over all those forms for drawing on
a horizontal surface in which the microscopical image is seen after
several reflections, and the pencil direct.
Curtis’s Camera Lucida Drawing Arrangement.*—Mr. Bulloch’s
new “Congress” stand has an arrangement for drawing, suggested
by Dr. L. Curtis, “ which is designed to do away with some of the
difficulties attending the use of the ordinary camera lucida. A little
table is fastened to the limb by milled-head screws; paper is placed
upon this for drawing. One of Hartnack’s right-angled camera
lucidas is used. Drawing can be done in any position of the
Microscope. There is hardly more preparation required for this
than would be required to change an eye-piece. The comfort of this
arrangement, when one is doing work which requires much drawing
while observation is going on, needs to be experienced to be
appreciated.”
Drawing on Gelatine with the Camera Lucida.t—M. Créteur
uses a metallic point for drawing objects with a camera lucida, the
drawing being made not on paper, but on a sheet of gelatine laid on a
dark ground. The shining point is always visible, and is claimed to
provide a remedy for the indistinctness of the point of the pencil, which
is the chief difficulty experienced in drawing with the camera by the
ordinary method. The drawing can also be readily transferred to
stone.
It is questionable whether the advantage gained through the
greater distinctness of the drawing-point is not more than counter-
balanced by the disadvantage of not being able to draw on paper. As
the particular benefit claimed appears to rest upon the shining
point, that could be obtained without great difficulty with an ordinary
pencil.
Iris-Diaphragm for varying the Aperture of Objectives.——In
1869, Dr. Royston-Pigott applied an Iris-diaphragm behind the
objective for reducing the aperture of objectives, in support of the
view which he was then advocating that wide-aperture objectives
produced confused images.
The editor of the ‘ Northern Microscopist’ has recently suggested
the use of such a diaphragm to enable penetration to be obtained
with wide-angled objectives of different apertures. Fig. 48 is a side
view of the apparatus, as made by Mr. C. Collins, and Fig. 49 a front
view. The upper end in the former figure screws into the microscope-
tube, while the lower receives the objective. The diaphragm is
opened or shut by sliding the lever projecting at the side. The
partial closing of the diaphragm does not, of course, contract the
field, but diminishes its brightness by obstructing the passage of a
greater or less part of the cone of rays.
* Amer. Mon. Micr. Journ., iii. (1882) p. 13.
+ Bull. Acad. R. Méd. Belg., 1880, p. 617.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 263
In some remarks on the use of the apparatus it is pointed out *
that it shows the value of wide apertures for good definition, for if a
preparation of the proboscis of the blow-fly be observed with an inch
objective having an air angle of 30°, the view is superb, the pseudo-
tracheal markings come out well-defined and sharp; but close the
shutter until an angle of 14° or less is obtained, and examine again,
when it will be found that the definition is not nearly so good, while
there is more penetration, the whole of the pseudo-tracheal tube being
observed under one focussing. While in this condition, the eye being
still applied to the tube, open the shutter to its full extent, and the
effect of wide aperture will demonstrate itself.
“‘Perhaps the best object to show the amount of penetration
possessed by objectives of low angle, may be found in the micro-
fungus, Myxotrichum deflexum, or M. chartarum, observed under the
1-inch objective. The former object consists of little patches of grey
downy balls, from which arise a number of radiating threads, fur-
nished with a few opposite and deflexed branches. Under an inch
objective of 30° air angle, but few of these branches can be seen
under one focussing, the remainder being enveloped in a haze of
light ; but if a central layer be focussed, the simple closing of the
shutter will suffice to bring the superior and inferior layers into view,
though, of course, the image is not so bright and well defined as
before.”
Gundlach }-inch Objective t—Dr. L. Curtis recently exhibited to
the State Microscopical Society of Illinois a new 4-inch objective
made by Gundlach, and claimed by the maker to have an angle of
100°. The back lens is large, and extends beyond the border of the
opening in the screw. This opening, therefore, acts as a diaphragm.
In order to secure the benefit of the full aperture, the portion of the
objective can be removed, and an adapter furnished with the Butterfield
broad gauge screw can be substituted. It has also another screw of
about the same diameter as the Butterfield screw, but provided with
a finer thread. The name and description of this screw were not
known. The front of the objective is ground down to a conical
* North. Microscopist, ii. (1882) pp. 13-14 (2 figs.).
+ Science, iii. (1882) pp. 19-20.
264 SUMMARY OF CURRENT RESEARCHES RELATING TO
shape. For ordinary use this front is covered with a brass cap,
having an aperture in the centre to allow the conical end of the
objective to pass through. The cap can be removed when it is desired
to use the objective for the examination of opaque objects. On
removal of the cap the conical sides of the lens are seen to be covered
with some sort of black varnish to prevent the passage of outside light.
A Lieberkuhn is furnished, which can be screwed on in place of the
cap while examining opaque objects.
Scratching the Front Lenses of Homogeneous-immersion Ob-
jectives.—It was recently objected to homogeneous-immersion objec-
tives that the necessity of wiping the oil from the front lens after
each observation was fatal-to their utility as in time the front surface
would thus become so scratched as to render the objective unfit for
use.
This objection, however, overlooks the fact that even assuming
it was really impossible to properly clear off the immersion fluid
without “scratching” the lens, such scratches would not interfere
with the use of the objectives. As the fluid used for immersion is
homogeneous, that is, may practically be considered fluid crown glass,
the scratches are optically obliterated as soon as they are in contact
with the oil or other medium; in fact, it will be seen on reference to
the original paper of Mr. Stephenson on homogeneous-immersion
objectives,* that one advantage of the system was pointed out to be
that in petrographical work the very imperfect polishing of thin sec-
tions of minerals, which had previously been a source of difficulty,
was overcome by the approximately optical identity of the object and
immersion fluid.
Fluids for Homogeneous Immersion.{— Dr. H. van Heurck,
Director of the Antwerp Botanical Gardens, has undertaken an ex-
tended investigation of fluids suitable for homogeneous immersion,
which (1) should have an index of 1:510-1-520 (line F), and (2) a
dispersive power of 0:006 (between D and F), (3) should not be too
fluid, and (4) should not attack the varnish of the slides.
Amongst the chemical solutions hitherto suggested, Dr. van
Heurck mentions Bassett’s fluid (which attacks varnish), chloride of
cadmium in glycerine, iodide of zinc in glycerine, sulpho-carbolate
of zinc in glycerine, and distilled chloride of zinc (difficult to use and
not capable of being well preserved). Of the vegetable substances,
cedar oil and oil of copaiba are referred to. The first is a product
not of the cedar, but of Juniperus virginiana, and is much too fluid, and
attacks the varnish of the cells. The second (distilled from different
species of Dipterocarpus) is a little less fluid and therefore better.
To remedy the inconvenience of the extreme fluidity of cedar-oil,
dammar has been dissolved in it, by which also its index may be raised
to 1:54. Professor Abbe has recently suggested to the author that an
excellent fluid may be obtained by dissolving dammar until the index
is 1-520, and then reducing it to 1°509 by the addition of castor-oil.
* See this Journal, i. (1878) p. 52.
t Bull. Soc. Belg. Mier., vii. (1881) pp. xxii,-xxxi. -
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 265
In his examination of new fluids, Dr. van Heurck met with no
sufficient success amongst chemical products, but of vegetable sub-
stances three were discovered which appear to be in every way
suitable.
The first is a solution of the resinous gum known as oliban (from
several species of Boswellia of Hast Africa) partially dissolved in
cedar-oil. It gives a fairly thick lemon-yellow liquid of refractive
index 1-510, and dispersive power 0:0077. To prepare the liquid,
pieces of very pure oliban are powdered finely, and the powder, mixed
with its own volume of cedar-oil, is heated in the water-bath in a
glass beaker for 2-3 hours. It is then left till the next day, when the
supernatant liquid is drawn off.
The resin (élemi) of Brazil, and the white oily tacamaque of
Guibourt give equally good solutions with oil of cedar. By dissolving
the tacamaque in the oil a liquid is obtained with a refractive index
of 1-519, and dispersive power of -0074. By adding castor-oil to
the solution in suitable quantity the index is lowered to 1-508, and
the dispersive power to 0:0072. To prepare the solution, 20 parts
by weight of the tacamaque are dissolved in the water-bath in 22 parts
of cedar-oil and 14 parts of castor-oil added.
According to Professor Abbe, the latter solution and that of
dammar in cedar-oil constitute the two best fluids for homogeneous-
immersion objectives.
The third is copaiba of Maracaibo, derived from Copaifera offici-
nalis. ‘That found in commerce at Antwerp, and apparently authentic,
had an index of 1°519, whilst a specimen from Guibourt of copaiba
of Para was only 1°506. It dissolves readily in cedar-oil. Another
liquid of 1°510 index and -0076 dispersive power is obtained by dis-
solving 7 parts of light vaseline in 30 parts of copaiba. A very
thick liquid results, not attacking varnish even after a contact of 24
hours. Ifit is found to be too thick it can be diluted by mixing with
it a solution of copaiba in cedar-oil.
Other liquids from conifers were tried, but in all the dispersive
power was found to be too high.
Dr. van Heurck fears that it will be very difficult to discover any
substances which will satisfy microscopists who prefer aqueous
liquids.
Advantage of Homogeneous Immersion.*—Dr. van Heurck also
says that “the suggestion of Mr. Stephenson .... constitutes
certainly the greatest advance which has been made in microscopy
during late years. Personally we have been able to appreciate, better
perhaps than any one, the importance of such objectives, for it is
owing to them that the thousands of drawings in the ‘Synopsis des
Diatomées de Belgique’ could be furnished in a relatively short time.
When we think of the trouble that monochromatic illumination has
caused us, and the frequent interruptions necessitated by the absence
of the sun, we cannot sufficiently congratulate ourselves upon this
fortunate discovery, which has enabled us to advance, by a good many
266 SUMMARY OF CURRENT RESEARCHES RELATING TO
years perhaps, the publication of our work, all the drawings of which
have been made or perfected by homogencous-immersion objectives.”
Vertical Illuminator for examining Histological Elements.*—
Dr. E. van Ermengem commends the vertical illuminator for the
illumination of such of the histological elements as can be mounted
on the cover-glass dry. ‘ Blood-corpuscles present an extraordinary
appearance, their colour a lively red, their relief very appreciable,
and the slightest inequalities on their surface clearly visible.” Good
results had also been obtained in the examination of semen, mucus,
pus, and liquids containing bacteria, &c.; also of the minute structure
of muscles and nerve-fibres.
Griffith's Parabolic Reflector.;—Mr. W. H. Tivy describes a
method suggested to him by Mr. E. H. Griffith for utilizing a spoon
for a “ parabolic” reflector. Wind a clean copper wire of =, inch
diameter closely round the base of an objective three times, twisting
and bending the ends for a length sufficient to reach a little beyond
the end of the objective. Cut a section of about half an inch from the
bowl of a new plated teaspoon, and solder the convex side to the ends
of the wire, also making the loop solid with solder, and filing it up
to a good fit and figure, so that it will slip easily on and off the
objective. The reflector is adjusted by bending the wire. “Thus I
have a handy and useful piece of apparatus, at the cost of the spoon,
30 cents.”
Forrest's Compressorium.—This compressorium (Fig. 50), de-
signed by Mr. H. E. Forrest, is specially constructed with a view
to cheapness. It consists of a strong glass (or if desired brass) plate,
Fic. 50.
3 inches by 1} inches, with ground edges. A small brass screw
passes through the plate, the point projecting upwards through it
about 3 inch. A brass arm, bent so as to form a spring, rotates upon
the screw as on a pivot, and carries at one end a brass ring holding a
thin cover-glass, 1 inch in diameter, which covers the centre of the
plate when in use. A milled nut works upon the screw above the
arm, and when screwed down brings the cover-glass in contact with
the glass plate. The spring acts upon and raises the cover, if the
nut is unscrewed, so that the two glasses can be fixed at any degree
of proximity required.
Julien’s Stage Heating Apparatus.{—In a paper on the examina-
tion of carbon dioxide in the fluid cavities of topaz, Mr. A. A. Julien
thus describes the method employed in his investigations.
* Bull. Soc. Belg. Micr., vii. (1881) pp. xxxvii.—xl.
+ Amer. Mon. Micr. Journ., ti. (1881) p. 238.
t¢ Journ. Amer. Chem. Soc., iii, (1881) 12 pp. and 4 figs.
b
;
‘
a
2
é
ee
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 267
“The qualitative identification of carbon dioxide in the cavities of
a mounted thin section of a mineral may be determined, at least with
probability, after some experience, through various optical appear-
ances and physical characteristics which have been often described.
Tt is usually effected with certainty and ease, through the rapid and
enormous expansion and ultimate disappearance, either of the liquid
or of the gaseous bubble on the application of a gentle heat for a few
seconds, such as that of a cigar, the heated end of a rod, or jet of hot
air, or even a jet of the warm breath conveyed through a flexible
rubber tube. When the slide and the section are thin, even the heat
(87° C.) of the tip of one’s finger applied for a few seconds to the
bottom of the slide, without removal from the stage of the Microscope,
may be sufficient to produce the characteristic phenomena, e.g. the
contraction and disappearance of a bubble whose size is relatively
small to that of the liquid in which it floats.
For the determination of the temperature of disappearance of the
bubble, which may vary from 20° to 32° C., several forms of stage
heating apparatus may be employed (those of Nachet, Beale, Fuess,
Schultze, Chevalier, Dujardin, Ransom, Polaillon, Ranvier, and
Vogelsang). In place of all these, a simple and inexpensive apparatus
may be substituted, consisting of a miniature water-bath, in which are
immersed the entire section and slide, the bulb of the thermometer,
and the nose of the objective. It consists of a box of tinned copper
(Fig. 51) (tinned iron is liable to rust), of length sufficient to project
a few centimetres on either side of the stage of the Microscope em-
ployed; the one I use being 23 cm. in length, 4 cm. in width, and 3 em.
in depth. This is laid across the stage, separated from the metal by
thin plates of cork cc, and is heated by a short wax taper (night-
light) underneath either extremity. The slide s may rest upon the
bottom, guarded from the metal by little rubber bands rr beneath its
ends, and wedged firmly by a little wooden wedge w beneath the
horizontal thermometer bulb 6; or a thermometer with a ring-shaped
bulb may be inserted, upon which the slide may rest directly, firmly
attached by one or two slender rubber bands. The thermometer
should be of guaranteed accuracy, with wide degrees, subdivided if
possible, with a range which need not much exceed 20° to 32° C.
The preparation is then covered by any pure and clear water, prefer-
ably filtered (distilled is unnecessary), to a depth of about 2cm. A
circular aperture in the bottom of the box, 18 mm. in diameter, is
covered with glass attached by cement, and through this the light is
thrown up from the mirror. The cavity to be examined is then care-
268 SUMMARY OF CURRENT RESEARCHES RELATING TO
fully adjusted and focussed, a taper is lit, and the eye remains at the
eye-piece until the critical point is reached. The glass tube ¢, with
its point terminating just below the edge of the slide, is connected
with the mouth during the experiment by a small rubber tube. As
the temperature slowly rises, a constant current of small bubbles of
the warm breath (whose temperature, 32°, only assists the operation)
may be blown with little fatigue through the tube, to effect a thorough
intermixture of unequally heated layers in the water stratum. The
determination of the temperature of disappearance of the bubble is
easily obtained within five minutes, and that of its reappearance in
about the same time. A low-power objective may be carefully wiped
if its anterior lens is dimmed by flying drops or rising vapour, when a
high temperature is being attained ; but it is best to insert the whole
objective in a small, narrow glass beaker floating upon the surface of
the bath over the preparation.
The apparatus, as thus constructed, may, the author thinks, be
found the most convenient warm stage when high temperatures are
required ; but another still more simple, lately devised, will best serve
for the determination of carbon dioxide, and consists of the following
parts :—
First, a shallow glass tank (Fig. 52), with thin and well-annealed
sides, of size sufficient to enclose the slide, upon which the thin
Fig. 52.
section is mounted. For this purpose I use a small chemical beaker
B, with the thinnest bottom, and with its upper portion cut off, forming
a thin round glass tank, about 6 cm. in diameter, and 8 cm. deep.
Secondly, a plate of copper or brass, like that used in Schultze’s
apparatus, or more simply one of the form represented in the figure d e.
Its dimensions, proportioned to those of the beaker-tank and of the
stage of a large Microscope, are as follows:—Length, 23 cm.;
diameter at centre, 6°5 cm.; width of arms, 3:5 cm.; central aperture,
2°5cm.; height of wire support, 13 cm.; thickness of plate, 1 mm.
Each arm is wrapped in pasteboard, to prevent radiation, to the extent
indicated by the shaded portion.
Thirdly, a delicate thermometer, with a small, short bulb bent at
right angles to the stem, and a very fine column, to obtain sufficient
sensitiveness to minute variations of temperature, and complete
immersion of the bulb in the small volume of liquid employed in the
bath. The scale need not exceed in range from about 20° to 82° C.,
the thermometer being of such length that when in position the scale
from 27° to 30° C. may be on the level of the eye-piece of the Micro-
ZOOLOGY AND BOTANY, MIOROSCOPY, ETC. 269
scope, and readily visible without motion of the head. Each degree
of the column should be about a cm. in length, and subdivided to
tenths.
Lastly, a pointed glass tube, with flexible rubber connection for
blowing, and a wire supports, to receive both this and the thermo-
meter, attached to the metal plate.
. The latter is laid upon the stage of the Microscope, separated by
thin plates of cork or a perforated piece of pasteboard; the tank,
supplied with about 40 cc. of water, is placed over the central aper-
ture a, and a taper beneath an extremity of one arm of the plate, and
the apparatus is then ready for use in the way already described, the
water of the tank being heated by conduction through the metal plate.
‘The section of the mineral is best mounted upon a very thin slide,
45 mm. by 26 mm., and this is guarded as before with rubber bands,
and held down by one or two little brass weights. Only a single
' taper is necessary for the low temperature required in the examination
of carbon dioxide cavities, and even with this a temperature of 43° C.
may be obtained in the bath within a few minutes. The disappearance
of the bubble may be completed in less than five minutes, the taper
being removed as soon as the rising column approaches within 2 or 3
degrees of the critical point, roughly determined by a previous trial.
If two tapers are used, the temperature of the water may be raised to
55° in about 20 minutes, or even much higher, by the use of Bunsen
gas burners. In summer the temperature of the atmosphere alone
may be sufficient, especially if assisted merely by the current of warm
breath, to obliterate the gas bubble. Its return may be readily caused,
in a warm atmosphere, by adding from time to time a few drops of
cool water to the bath, while the eye remains at the eye-piece, and a
steady current of air is blown through the glass tube. Mounted
slides used for such experiments must be labelled by writing with a
diamond, or the paper label may be rendered waterproof by being
coated successively with weak size and any transparent varnish, such
as copal or shellac.
From these experiments it may be inferred that with this appa-
ratus, which may be called the immersion warm bath, it matters little
for most purposes what liquid, stand, or objective is employed; that
water is preferable to glycerine, from its greater mobility, convenience,
and lack of cost; that its bulk is immaterial, so long as the bulb of
the thermometer is covered; that it is decidedly advantageous to
immerse the anterior lens of every objective in the bath, to avoid the
annoying interference with observation produced by the vibration of
the surface, and by the necessity for repeated refocussing, when the
objective is above the surface of the liquid ; that careful determination
on minute cavities, with high powers, carried on slowly to enable the
preparation, objective, and thermometer to assume the same tempera-
ture, may be as accurate as any others; and that there is no difficulty
in obtaining satisfactorily the two determinations within ten minutes
to an approximation of about one-twentieth of a degree.
The descriptions of this method, and of these forms of apparatus,
have been given in the more detail, inasmuch as they may be of
270 SUMMARY OF CURRENT RESEARCHES RELATING TO
service in many other branches of thermal microscopy where the exact
determination of the temperature applied is desirable, e. g. as sug-
gested by Mr. A. H. Elliott, in the determination of the melting point
of rare chemical substances, &c. For this purpose, the apparatus in
Fig. 51 might be supplied with another tube, on the opposite side to
those represented, through which might be inserted, beneath the
objective, a small glass tube containing the substance to be examined,
and thus immersed, by the side of the thermometer bulb, in the water,
oil, paraffin, or other liquid which the circumstances may require for
the bath.”
Beck’s Achromatic Condenser for Dry and Immersion Objectives.
—In an earlier form of (dry) condenser (Fig. 53), Mr. Beck made
use of a revolving front rotating a series of lenses mounted on a plane
Fig. 53. Fig. 54.
surface over the back combination. This plan was, however, only
available for a dry condenser ; if used for immersion, the connecting
fluid would be drawn away by capillary attraction.
To avoid this inconvenience, the new form shown in Fig. 54 has
been devised, the movable series of front lenses being mounted
in a segment of a sphere and rotated by a milled head acting on a
pinion and toothed disk. The first lens, when brought over the back
combination, has a low angle, and is intended for use without fluid for
histological objects. By revolving the diaphragm, the angle can be
varied from 85° to 7°. The next is a full aperture lens with which,
by revolving the diaphragm, the angle can be varied from 180° down-
wards. The third lens, with full aperture of diaphragm, has an
angle of 110° in glass = 1°25 N.A., and is truncated, cutting out the
central rays. The fourth lens has also an aperture of 1°25, and is
truncated, so as to stop out all rays up to 180° inair. The fifth is
similar to No. 3, but the periphery is painted over, so as to allow
pencils only at right angles to pass.
Pennock’s Oblique Diaphragm.*—Mr. E. Pennock suggests an
adaptation of Mr. Mayall’s spiral diaphragm,f to be attached to the
* Amer. Journ. Micr., vii. (1881) p. 161 (8 figs.).
+ See this Journal, i. (1881) p. 126.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. DA
under side of the stage, for shutting off all light except a small pencil
from the mirror. It may be mounted in either of two forms: the one
to fit into the usual tube, which,
in the cheaper Microscopes, is Fie. 55,
attached to the under side of the
stage, the other to screw directly
into the stage aperture.
The device is shown in Fig. 55.
The milled edge serves to rotate the
plate with the spiral slot over the
radial slot (shown by dotted lines),
thus giving varying degrees of
obliquity.
Stereoscopic Vision with Non-stereoscopic Binocular Arrange-
-ments.—It will be remembered that in his paper “ On the Conditions
of Orthoscopic and Pseudoscopic Effects in the Binocular Micro-
scope,’ * Professor Abbe pointed out that an orthoscopic (stereo-
scopic) effect was produced if the inner halves of the “ Ramsden
circles” just above the eye-pieces were shut off by diaphragms (that
is like O, Fig. 56), and a pseudoscopic effect when the outer halves
were so dealt with (that is like P, Fig. 57).
Fic. 56. Fic. 57.
0 P
Dr. A. C. Mercer, of Syracuse, U.S.A., points out that this explan-
ation solves a difficulty which has perplexed many microscopists, and
has hitherto remained unexplained. Powell and Lealand’s high-
power binocular is essentially non-stereoscopic, and theoretically ought
not to give any appearance of relief to the objects. It has nevertheless
been frequently observed that a distinctly stereo-
scopic effect was obtained, and this was attributed Fic. 58.
entirely to the imagination of the observer. Dr.
Mercer, however, shows that it is a true and not an
illusory effect, and that it depends upon the extent
to which the eye-pieces are separated.
When the eye-pieces are at such a distance apart
that the Ramsden circles correspond exactly with
the pupils of the eyes, centre to centre (Fig. 58), the
object appears flat. If, however, they are racked
down so as to be somewhat nearer together, the
centres of the pupils fall upon the outer halves of
the Ramsden circles, and we have the conditions
for orthoscopic effect; while if they are racked ©
up so as to be more separated the centres of the pupils fall on the
inner halves and we have pseudoscopic effect.
This is quite in accordance with what takes place in the use of
* See this Journal, i. (1881) pp. 203-11 (3 figs.).
*
Y
ZY
i)
272 SUMMARY OF CURRENT RESEARCHES RELATING TO
eye-pieces, the halves of which are actually covered with diaphragms,
for when the inner halves are cut off the tubes naturally require to be
racked down to diminish the separation of the eye-pieces, and in the
converse case to be racked up; Dr. Mercer also satisfied himself by
experiment as to the validity of his deductions by observing sugar
pills pushed half-way through holes in black cards, the pills being
marked with cross marks in pencil to increase the effect. They could
be made to appear convex, concaye, or flat, according to the position
of separation of the draw-tubes.
We have, for simplicity, referred to the covering up of both halves
of the eye-pieces, but it is not of course necessary to cover up more
than one.*
In order to obtain the best stereoscopic effect the halves (or one
of the halves) of the eye-pieces of the Powell and Lealand or other
similar binocular arrangements should be actually shaded by dia-
phragms so as to aid in properly centering the pupils, but Dr. Mercer’s
object is to show that the effects observed with ordinary eye-pieces
are explicable upon proper theoretical principles, and so to relieve
those observers who have insisted upon the existence of true ortho-
scopic effects in such cases, from the reproach which has un-
justifiably attached to them on account of their supposed abnormal
and unscientific development of a power of drawing upon their
imagination.
[The Bibliography for the period intervening between that contained in the
Journal of October 1880 and the end of 1881, will be found in the Appendix to
the next volume. ]
Axsse’s Experiments on the Diffraction Theory of Microscopical Vision.
[General Remarks. ]
Journ, of Sci., TV. (1882) pp. 118-9.
Acme Microscopes. Amer. Natural., XVI. (1882) p. 261.
American Society of Microscopists.
[Review of Proceedings for 1881, and remarks on the meeting at Elmira
for 1882.]
The Microscope, I. (1882) pp. 175-7.
Angular Aperture.
[Letter by ‘ Akakia,’ describing Dr, Robinson’s method of measurement. |
Engl. Mech., XXXIV. (1882) pp. 454-5.
Browne.t, J. T.—A much-needed stop.
[Suggestion for a “ thumb-screw ” to prevent Microscopes at Soirées being
focussed too low to the injury of tlie slides.]
Amer. Mon, Micr. Journ., III. (1882) p. 39.
Bvtiocu’s New “ Congress” Stand.
Amer. Mon, Micr, Journ., III. (1882) pp. 9-13 (2 figs.).
Carlisle Microscopical Society—Inaugural Address by the President, Canon
Carr. North, Microscopist, 11. (1882) pp. 17-19.
Carr, E.—Scee Carlisle.
Cheap Microscopes.
{Letter by C., advocating the encouragement of their purchase and
display, and further discussion by Welborn, G., Ollard, J, A., Cooper,
C. C., F.; J., E. Holmes, A., E. C., and Medehanstade.]
Eng!. Mech., XXXIV. (1882) pp. 470, 495-6, 520-1, 545.
Cox, J. D.—Prof. Rogers’ Micrometers.
Amer, Mon. Micr, Journ., IIL. (1882) pp. 23-5.
* See this Journal, i. (1881) p. 211, Fig. 38.
1
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 273
Crisp, F.—Notes sur l’Ouverture, la vision microscopique et la valeur des
objectifs 4 immersion a grand angle. (Notes on Aperture, Microscopical Vision,
and the value of wide-angled Immersion Objectives)—contd.
{ Transl. of paper I. (1881) pp. 303-60.)
Journ. de Microgr., V1. (1882) pp. 44-8, 91-5 (13 figs.).
Curtis, L.—New 3-in. Gundlach Objective of 100°.
Amer, Mon, Micr. Journ., IIL. (1882) pp. 19-20.
The Microscope, 1. (1882) pp. 194-5. Science, III. (1882) pp. 19-20.
Davis, G. E.—The limiting Diaphragm or Aperture Shutter.
North. Microscopist, 11. (1882) pp. 13-14 (2 figs.) p. 75.
Amer. Mon. Micr. Journ., U1. (1882) pp. 49-50.
Engl. Mech., XX XY. (1882) p. 25 (2 figs.).
3 a A Visit to an Objective Factory.
[W. Wray’s, Highgate. }
North. Microscopist, 11. (1882) pp. 21-4.
Drieret, L.—Abbe’s Camera Lucida.
Bot. Centralbl., TX. (1882) pp. 242-3 (1 fig.).
Forrest’s (H. E.) Compressorium. North. Microscopist, Lf. (1882) p. 51.
GrirritH, E. H.—The Griffith Cell. Amer. Mon. Mier. Journ., U1. (1882) p. 9.
GuILLemIn, A.—Le Monde Physique. Tome Il. La Lumiere. (The Physical
World, Vol. I, Light.)
[Contains a Chapter on the Microscope (20 pp., 20 figs., and 3 coloured
Plates), 2 section on Microscopical Photography (7 pp. and 5 figs.), and
one on the Applications of Photography to the Arts and Physical and
Natural Sciences, 4 pp. and 3 figs.]
8vo, Paris, 1882. 668 pp., 353 figs., and 26 plates.
Hrrcucock, R.—Large and Small Microscopes.
[Rejoinder to C. Stodder.]
Amer. Mon. Wicr. Journ., U1. (1882) pp. 16-7.
be 5, The Microscopist.
{Further reply as to Stowell’s ‘ The Microscope.’]
Amer. Mon. Mier. Journ., I11. (1882) pp. 18-9.
Homes, E.—Drawing, &c., from the Microscope.
[Recommends Mr, Dallinger’s plan of drawing on finely smoothed
glass. |
Sci.-Gossip, 1882, p. 39.
Journal of the Royal Microscopical Society for 1881.
[Note on the small number of original contributions to the ‘ Transactions’
and the reason for it.]
Journ. of Sci., [V. (1882) p. 56.
Microscopical Societies.
[Note as to an intended alteration in the printing of their Reports.]
Amer. Mon. Micr. Journ., U1. (1882) pp. 14-5.
Mus, J. L. W.—Dark-field Illumination by the Bull’s-eye Condenser.
[Placed beneath the stage, plane side uppermost, with a spot of black
paper in the centre. ]
North. Microscopist, 11. (1882) p. 39.
5 * Substitute for a Revolving Table.
[A piece of table oil-cloth, 15 in. sq., the cloth side turned to polished and
the oil side to painted tables. ]
North. Microscopist, 11. (1882) pp. 39-40.
Nacuet, C. §., Death of. Journ. de Microgr., V1. (1882) pp. 3-4.
Objectives, Verification Department for.
{Tabular results of measurements of objectives. ]
North. Microscopist, IL. (1882) pp. 7, 24, 59.
OLLarD, J. A.—Mr. Kitton’s Illumination.
[Commending same, and recommending the use of distilled filtered water,
filling the globe full to prevent a shaky light, and not using too much
sulphur chlorate (first filtered). ]
Sci.-Gossip, 1882, p. 47.
Pockiinctoy, H.—The Microscope at Home.
Engl. Mech., XXXIV. (1882) pp. 538-9, 560-1.
T
Ser. 2.—Vot. II.
274 SUMMARY OF CURRENT RESEARCHES RELATING TO
PrRinGsHEIM’s Photochemical Microscope.
Quart. Journ. Micr, Sci., XXII. (1882) p. 86.
S., H. C.—An “ English Mechanic ” Microscopie Club.
Engl. Mech., XXX1V. (1882) p. 615.
Saut’s and Swirt-Brown Microscopes.
Engl. Mech., XXXIV. (1882) p. 463 (3 figs.).
Scuroper, H.—Ueber Projektions-Mikroskope. (On Projection Microscopes.)
Centr. Zig. f. Optik u. Mech., UII. (1882) pp. 2-4, 15-17 (1 fig.).
Surerersotrom, W.—Improvements in Photo-micrography.
North. Microscopist, 11. (1882) pp. 48-9 (2 figs.) p. 75.
Fe » Use of the ‘ Aperture-shutter’ in Photo-micrography.
North. Microscopist, II. (1882) p. 75.
Slow motion for Micro. Stand.
[Letter by ‘Sunlight,’ describing the ordinary form used with the
‘ Jackson Model.’ |
Engl, Mech., XXXIV. (1882) p. 457 (1 fig.).
Srattyprass, H. M.—Microscopic Illumination.
[Approval of F. Kitton’s Hollow Glass Sphere Method, I. (1881) pp. 112-3
—by adding a few drops of pure sulphuric acid, cloudiness of the liquid
is prevented. |
Sci.-Gossip, 1882, p. 64.
Stopper, C.—Large vs. Small Stands.
{Reply to R. Hitchcock’s Criticism. ]
Amer. Mon. Micr. Journ,, III. (1882) pp. 13-4.
SurroLk, W. T.—On Microscopical Drawing. Sci.- Gossip, 1882, pp. 49-50.
TISSANDIER.—Microscopie Photography in Paris.
(Abstr. of article from ‘ La Nature.’ ]
Engl. Mech,, XXXIV. (1882) p. 561.
p. Collecting, Mounting and Examining Objects, &c.
Injection of Invertebrate Animals,*—G. Joseph uses filtered
white of egg, diluted with 1 to 5 per cent. of carmine solution, for
cold injections. This mass remains liquid when cold; it coagulates
when immersed in dilute nitric, chromic or osmie acids, remains
transparent, and is sufficiently indifferent to reagents. A mass of
similar properties is made of glue liquid when cold, coloured with
the violet extract of logwood reduced with alum. Injection is effected
in the case of worms (leech and earthworm), by way of the ventral
or dorsal vessel, with large Crustacea by the heart or the ventral
vessel which lies in the sternal canal.
In many cases, especially when lacunar spaces have to be filled,
useful preparations are obtained by natural injection (auto-injec-
tion, or autoplerosia), Natural injection of Meduse is effected
without injuring the vessels; in the case of Crustacea, Insects, and
Mollusca, through a slit with an opening at the side remote from it.
Medusze are laid in a glass vessel, with the bell downwards, and a
bell-jar ending in a narrow tube above is placed over it and made
air-tight; after the Medusa is covered with the injection-mass, the
air in the glass is exhausted, and the sea-water running out by slits
in the lower side of the annular canal the coloured fluid runs in.
* Ber. naturw. sect. Schles. Ges., 1879, pp. 36-40, Cf. Zool. Jahresber. Neapel
for 1880, i. pp. 45-6,
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 275
In the case of leeches and large species of earthworms, the natural
injection is made from the ventral sinus. In all cases a glass tube is
used, with a finely drawn-out point. The injection is complete when
the injection issues from the counter-opening.
Animals to be injected alive are kept quiet by cold (laying upon
ice). Besides the animals mentioned, large caterpillars, beetles,
Libellulid larvee, locusts, &c., have served as objects for injection ;
the glass cannula is introduced into the posterior end of the dorsal
vessel, and the counter-opening is made in the ventral vessel, and
vice versa.
Cold Injection Mass.*—A. Wikszemski describes a modification of
Pansch’s method:—Thirty parts by weight of flour and one of ver-
milion are mixed while dry, and then added to 15 parts by weight of
glycerine and subjected to a continuous stirring until of a homogeneous
viscous consistency ; then 2 parts of carbolic acid (dissolved in a little
spirit) are added to it, and finally 30 to 40 parts of water. This injec-
tion mass is specially adapted for subjects already injected with carbolic
acid (in the proportion of 15 part by weight each of carbolic acid,
spirit, and glycerine to 20 of water); 24 honrs are allowed to elapse
between the two injections. It is a good thing to introduce a little
dilute injection first.
Staining with Saffranin.;j—According to W. Pfitzner, staining
with saffranin is most successful with chromic acid preparations which
have been entirely freed from the acid, less so with substances
hardened in picric acid; the only tissues suited to it are those which
very readily take up colour, and these must be cut extremely thin.
The sections are transferred to the staining fluid (1 part saffranin, 100
absolute alcohol, 200 distilled water) from distilled water, are again
placed in distilled water after a few seconds, and then into absolute
alcohol, from which they are removed at the right moment (i.e. when
the nuclei are properly stained) to dammar varnish. The advantage
of staining with saffranin is that it affects the nucleiexclusively. Dr.
M. Flescht remarks that the advantage claimed by Pfitzner for
saffranin has been shown by Hermann to be shared with it by other
aniline dyes when applied in the same manner.
Staining with Silver Nitrate—Staining with nitrate of silver is
very difficult to effect in the case of marine organisms, owing to the
abundance in which chlorides occur inthem. R. Hertwig § meets this
difficulty by washing the animals (after hardening in osmic acid) with
distilled water until the water used for washing gives but a very
slight precipitate with solution of silver nitrate, and then allowing a
1 per cent. solution of the nitrate to act for 6 minutes.
* Arch. f. Anat. u. Entwick., 1880, pp. 232-4.
+ Morph. Jahrbuch, vi. (1880) p. 469. Cf: Zool. Jahresber. Neapel for 1880,
i. p. 43.
$ Ibid., pp. 43-4.
§ Jen. Zeitschr., xiv. (1880) p. 324.
we 2
276 SUMMARY OF CURRENT RESEARCHES RELATING TO
C. Golgi,* in studying the peripheral and central nervous fibres
of the spinal cord, exposes the nerves to the action of osmie acid,
chromic salts, and silver nitrate, according to certain methods of
combination. For example, a nerve is removed with care from a
freshly killed animal (rabbit), and placed in a mixture of 10 parts of
a 2 per cent. solution of potassium bichromate with 2 parts of 1 per
cent. osmic acid solution. After about an hour the nerve is divided
into smuller pieces of 3 to 1 cm. in length, and again placed in the
solution, where it is left some hours longer (it must be examined every
8 hours), and finally is placed for not less than 8 hours in 0°5 per
cent. solution of nitrate of silver, and then mounted in dammar
varnish in the ordinary way. Better preparations are produced by
placing nerves which have been exposed—in the case of peripheral
nerves 8 hours, of central nerves 10 to 15 days—to the action of
bichromate of potash, then from 12 to 24 hours to silver nitrate, and
mounted in dammar varnish without previous exposure to the light.
Staining Tissues treated with Osmic Acid.—Damaschino, in a
communication f to the Société de Biologie, advocates osmic acid in
the form of a solution of 1 per cent. for human spinal cord divided
into lengths of 1 cm., and for the spinal cord of smaller animals
treated entire ; he afterwards hardens in absolute alcohol. If it is
then not sufficiently hard, the preparation is saturated with gum before
being placed in the alcohol; the sections, which are penetrated with
gum, are transferred unstained to Canada balsam without being pre-
viously freed of gum by means of water.
Referring to this communication (which contains no really new
point), L. Malassez { remarks on the difficulty of staining substances
which have been treated with osmic acid, and for this reason he first
stains the sections with other staining matters, and then exposes them
to the action of osmic acid, and this in such a way as to allow only
the vapour of the solution of acid to act. He claims to have obtained
admirable results by this method, since in this way all the properties
of the osmic acid come into play without affecting the other staining
substances.
R. Hertwig § placed the animals (Ctenophora) examined by him
in a 0°05 per cent. solution of osmic acid, to which in some cases
he added acetic acid solution of 0°2 per cent. for from 5 to 15 minutes,
according as he wished to investigate the epithelium or the elements
of the gelatinous tissue; he then stained with carmine and finally
preserved in dilute glycerine.
Mounting the “Saw” of the Tenthredinide.||—-Mr. P. Cameron
describes his method of mounting and preserving the “saw” of the
Tenthredinide for microscopical examination, a method which can be
applied to microscopical mounting generally.
* Arch. per le Sci. Med., iv. (1880) pp. 221-46 (1 pl.). Cf. Zool. Jahresber.
Neapel for 1880, i. p. 44.
+ Gazette medic. Ann., li. (1880) p. 636. { Ibid., p. 637.
§ Jenaisch. Zeitschr., xiv. (1880) p. 315. Cf. Zool. Jahresber. Neapel for
1880, i. p. 41.
|| Trans. Entomol. Soc. Lond. 1881, pp. 576-7.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 277
With fresh specimens the saws can be extracted by pressing the
abdomen, when they will be protruded and readily extracted. With
old specimens it can be done equally well by placing the insect in a
relaxing-dish, or, more promptly, by steeping it in water for a day,
when they can be taken out in the same way as with fresh insects,
the only difficulty being experienced with insects full of eggs. For
their better examination the four pieces composing the ovipositor
proper should be separated ; after which they must be steeped in
turpentine for a day or two so as to get rid of air. This is be~t done
by enclosing them in a small folded piece of paper; and, if they be
properly labelled, many different preparations can be placed in the
turpentine-bottle together.
Next take a sheet of fine Bristol board, and cut it up into pieces,
say 12 lines x 9 lines, and punch at one end a round or square hole,
four or five lines across. On the lower side of this fasten, by means
of Canada balsam dissolved in benzine, a cover-glass. When this
has dried fill up half the cell thus formed with the same composition,
spreading it as evenly as possible, and in it arrange your preparation.
Put it aside for some hours in a place where no dust will fall on it,
then fill the cell with enough balsam to run over the edge of the cell,
place a cover-glass over it, and press it down. Ali that now requires
to be done is to allow the preparation to dry, taking special care to
keep it flat, to label it, and stick a pin through the card, by means of
which it is fixed in the cabinet alongside the insect from which the
part was taken. To examine it under the Microscope, all that is
necessary to do is to place an ordinary glass slide across the stage,
and put the card on it, in doing which it is not necessary to take
the pin out of it if a short pin be used.
The great advantage of this plan for entomological purposes is
that it does not necessitate the formation of two distinct collections,
which must be the case if dissections are mounted on glass slides,
which cannot of course be placed alongside the insects. Besides that,
it is cheaper, more expeditious, and safer ; for the cards are so light
that no injury comes to them from falling, or getting loose in the box.
If desired, a coloured ring can be put round the top object-glass by
the turntable in the ordinary way, but except for ornament, is not
necessary. ‘The author usually prepares two or three dozen of the
cards with one cover-glass on at a time, so as to have them ready for
use. The object of letting the dissections harden in the cell, half
filled with balsam, is that three or four separate parts may be
arranged in the most suitable way in the same cell without fear of
their being disarranged or injured when the top cover-glass is put on,
while both might happen if the whole operation was performed at once.
For the examination of the saws, a quarter-inch objective is
the best, the teeth, in some cases, are so fine that they are apt to be
overlooked if lower powers are used.
Mounting Butterfly-scales.*—Dr. D. H. Briggs recommends the
following process. Dissolve 1 part of Anthony’s “ French Diamond
* Amer. Mon. Mier. Journ., ii. (1881)_p. 227.
278 SUMMARY OF CURRENT RESEARCHES RELATING TO
varnish” in 2 parts of pure benzole. Apply a drop or two of the
solution to a slide, and in a few seconds, or as soon as the varnish has
set, press the wing of the butterfly gently upon the slide, and then
carefully lift it away. The scales will be found transferred to the
slide in their beautiful natural arrangement * on the wing. Make a
shallow cell around the mounting and apply the cover-glass. Canada
balsam must not be used, as it disarranges the object.
Imbedding Ctenophora.t—For imbedding Ctenophora (for the
most part after hardening in osmic acid), R. Hertwig employs gum-
glycerine very largely diluted with water ; it is allowed to remain in
contact with the air, with the substance to be cut immersed in it,
until it has acquired the consistency of a stiff syrup. Shrinkage of
the gelatinous tissue is to some extent obviated by this plan, owing
to the slowness with which it absorbs the constantly thickening gum-
glycerine.
Staining Living Protoplasm with Bismarck Brown.i—L. F.
Henneguy having treated Paramecium aurelia with an aqueous solution
of aniline brown (known in commerce as “ Bismarck brown”), was
surprised to see them assume a rather intense yellow brown colour,
and move rapidly about in the fluid. The colour first appeared in
the vacuoles of the protoplasm, and then it invaded the protoplasm
itself. The nucleus generally remains colourless, and thus becomes more
visible than in the normal state. Infusoria thus coloured were kept
for nearly fifteen days. If a yellow-tinted Paramecium is wounded
or compressed so as to cause a small quantity of the protoplasm to
exude, it is seen that it is really the protoplasmic substance which is
coloured. All Infusoria may be equally stained with Bismarck brown,
but no other aniline colours employed by the author exhibited the
same property, they only stained the Infusoria after death, and some
of them are in fact poisonous.
As it is generally admitted that living protoplasm does not absorb
colouring matters, and that Infusoria are essentially composed of
protoplasm, -M. Henneguy endeavoured to ascertain whether proto-
plasm in general, of animal or vegetable origin, behaved in the same
way in the presence of aniline brown.
A tolerably strong dose of Bismarck brown was injected under the
skin of the back of several frogs. After some hours, the tissues were
uniformly tinted a deep yellow, the muscular substance especially
had a very marked yellow tint. ‘The frogs did not appear in the
least incommoded,
Small fry of trout placed in a solution stained rapidly and con-
tinued to swim about.
Finally, a guinea pig, under whose skin some powder of Bismarck
brown had been introduced, soon presented a yellow staining of the
buccal and anal mucous membranes and of the skin.
Seeds of cress sown on cotton soaked with a concentrated solution
* It should be observed that the scales will have their under sides uppermost,
which is not the “ natural arrangement.”—Eb.
+ Jen. Zeitschr., xiv. (1880) pp. 313-14.
¢ Rey. Internat. Sci. Biol., viii. (1881) pp. 71-2.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 279
of the Bismarck brown sprouted, and the young plants were strongly
stained brown ; but on crushing the tissues and examining them under
the Microscope it was ascertained that the protoplasm of the cells
was very feebly coloured; the vessels on the contrary showed a very
deep brown staining up to their termination in the leaves.
The mycelium of a mould which had been developed in a solution
of Bismarck brown, was clearly stained after having been washed
in water, whilst it is known that the mycelium which frequently
forms in coloured solutions, picrocarmine, hematoxylin, &c., remains
perfectly colourless.
Other aniline colours injected under the skin of frogs stained the
fundamental substance of the connective tissue as deeply as did the
Bismarck brown; but the cells of the muscular substance remained
perfectly colourless.
The author concludes therefore that Bismarck brown possesses
the property of colouring living protoplasm both in plants and
animals.
Preservation of Infusoria and other Microscopical Organisms.*
_—A. Certes, in a note supplementary to his previous communications,f
says that five years’ experience has only confirmed his view of the
efficacy of osmic acid and iodized serum for preparing Infusoria ; but
sometimes, notwithstanding precautions, the animalcules become black
and opaque from a too prolonged action of the osmic acid; or,
especially when iodized serum or lemon juice has been employed as
a fixing reagent, mouldiness attacks the preparations either because
the bottles have been badly corked or precautions for excluding germs
from the preparations have been neglected.
It will be found however that ammonia (3) will clear prepara-
tions blackened by osmic acid, and thus the always dangerous use of
cyanide of potassium will be avoided ; but it is necessary to watch the
operation with care, the time of immersion in ammonia being
essentially variable according to the thickness of the animalcules and
the quantity of osmic acid in excess.
With regard to mouldiness, it is possible, with certain precautions,
to filter the liquid which holds the altered gatherings in suspension,
upon pure glycerine. To increase the hardening of the animalcules, the
liquid in excess is first removed and replaced by strong alcohol, by
picrocarinine, or by green picrate of methyl, it is then poured gently
on the glycerine, which, owing to its density, remains at the bottom
of the vessel, but previously the liquid to be filtered must be briskly
agitated so as to disengage the animalcules caught by their cilia in
the matted fibres of the moulds.
‘The Infusoria thus detached fall first to the bottom. The
patches of mycelium which offer more surface and consequently more
resistance do not sink, or sink much more slowly. Advantage is
taken of this circumstance to decant the liquid with a pipette, and to
collect from the bottom of the vessel the Infusoria which, being
isolated, are best adapted for observation.
* Bull. Soc. Zool. France, vi. (1881) pp. 36-37.
Tt See this Journal, ii, (1879) p. 331 ; iii, (1880) p. 847.
280 SUMMARY OF CURRENT RESEARCHES RELATING TO
In default of osmic acid, filtered lemon juice may be employed ;
but it is necessary to follow the operation closely in order to check at
the right moment the action of the reagent, which should be employed
in a strong dose, and which consequently would in the long run injure
the extremely delicate tissues of the Infusoria.
Impregnation by chloride of gold is generally successful after the
action of lemon juice. Often, however, the pulverulent deposit gets
entangled in the cilia of the Infusoria and obscures observation. Filtra-
tion upon glycerine reduces this inconvenience.
In conclusion, M. Certes indicates the process which he considers
best for preserving the intestines of Batrachians with the object of
examining the parasites they enclose. Having tied the intestine at
the two extremities, it is washed in distilled water and placed in a
solution of osmic acid (1-1000). After twenty-four hours’ immersion,
this solution is replaced by strong alcohol or by glycerinated water.
Under these conditions, Opaline and other inhabitants of the
rectum of Batrachians may be kept undistorted till they can be
examined.
Tn a subsequent paper,* the author mentions that he has met with
difficulties in the latter process. When the walls of the intestine are
too thick or are too much filled by food, there is so great an absorption
of the reagent that the Opaline and other parasitic Infusoria are
dissolved under the action of the liquids of the organism or by the
preservative liquids. He thinks it will be found sufficient to increase
the strength of the osmic acid solution, and to slit the intestine
longitudinally.
Staining the Nucleus of Infusoria.j—A. Certes has already
shownt the property possessed by cyanin or chinolin blue (and
Bismarck brown) of staining living tissues, the nucleus of Infusoria
not, however, appearing to be coloured either during life or even
several hours after death. Dr. Henneguy having pointed out to him
the analogous properties of a methyl violet, known as dahlia, M. Certes
has repeated his experiments with several violets, and has found that,
notwithstanding their very similar chemical composition, their action
varies considerably. Some are always toxic, and for all species of
Infusoria. Others only stain certain species out of those living in
the same liquid. Others—and this is the special object of his further
communication—stain the nucleus of living Infusoria, and more
strongly than the rest of the protoplasm. In general with the violets in
question, the cilia are always stained, and the liquid of the contractile
vacuole often participates (so far as could be judged) in the general
colouring.
The phenomena of selection of the colouring matter in regard to
the nucleus was clearly established, at first with B B B BB violet on
Balantidiuwm from the intestine of Bombinetor igneus, and then on
Paramecium, Vorticella, &c., with the same and dahlia violet. Gentian
* Bull. Soc. Zool. France, vi. (1881) p. 228.
¢ Ibid., pp. 226-7.
t See this Journal, i. (1881) pp. 527, 694.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 281
and 50 N violet on the contrary, notwithstanding their great colouring
power, did not exhibit any selective action with the nuclei.
As to the greater or less resistance which very closely allied
species oppose to the action of the same reagent, the author mentions
that he has found small species of Paramecium continue to live in-
definitely without staining, whilst all the others of equal or greater
size had entirely disappeared from the same liquid.
The staining of the nucleus of the Infusoria is, the author
(erroneously) says, “ a new fact, and it is so much the more interesting
to note that the most recent researches demonstrate the prepon-
derating part which the nucleus plays in the phenomena of nutrition
and reproduction, and, if one may so say, in the government of the
life of unicellular organisms.”
Aniline Dyes and Vegetable Tissues,*—Mr. J. M. Macfarlane, in
a paper on the action of some aniline dyes on vegetable tissues, records
some of the more important methods arrived at.
“ Staining of Laticiferous Vessels—Hvery botanist must have ex-
perienced the difficulty of obtaining thoroughly good preparations of
laticiferous vessels. Sachs recommends boiling in dilute potash ; but,
while tolerably good sections may be obtained in this way, several
difficulties are encountered. The points to be aimed at in preparing
this tissue are (a) the coagulation of the latex, so that it may continue
to fill the vessels; (b) the staining of the cut sections, so that the
vessels may be distinctly differentiated from the surrounding cellular
substance; (c) the successful mounting of these, so that the tint may
be permanently retained. The first part of the process is best accom-
plished by obtaining, for example, a large and entire root of Scorzonera,
so that extensive bleeding may be prevented. A suitable sized bottle
being filled with alcohol, pieces of the root from one to two inches in
length are cut and immediately placed in it. Coagulation of the
latex is quickly effected. After lying thus for a week or longer,
sections are cut with the hand, or by aid of a microtome. Thesecond
point is most important, and on its success the beauty of the object
will depend. The sections are placed in alcoholic solution of saf-
franine, obtained by dissolving 1 part of this dye in 800 parts
spirit. After 18 to 24 hours, they are removed from the stain and
decolorized by washing repeatedly in spirit. It will be found that
the stain leaves the cellular tissues rapidly, while it is retained by
the latex in the vessels. We will notice, lastly, the best method for
mounting these. While such media as balsam or dammar would
cause unnatural contraction, fluids, on the other hand—especially
acetic acid solution—are apt to act slightly on the dye. I have
found nothing to equal glycerine jelly, as it preserves the tint and is
easily worked.
Double Staining of Stems, dc—The dyes usually recommended for
this purpose are rosaniline and iodine green; but saffranine and
emeraldine are preferable, as the former is, for vegetable tissues, a
* Trans. Bot. Soc. Edin., xiv. (1881) pp. 190-1.
282 SUMMARY OF CURRENT RESEARCHES RELATING TO
most permanent dye, while the latter imparts a brighter colour than
iodine green.
Staining of Cell Contents.—While some aniline dyes act specially
on the thickened walls of cells, others are extremely useful for
demonstrating the structure of protoplasm. Heliocin and naphthaline
in this respect are valuable ; and eosin, though not an aniline dye,
is equally so. For epidermis cells and ordinary parenchyma the
latter is preferable. It is best prepared by dissolving 1 part in 1200
of alcohol. The specimens are allowed to lie for 5 minutes in the
stain, and are then washed in water and mounted in a cell with
acetic acid, or Goadby’s solution. The cells of Spirogyra, however,
have their minute structure beautifully revealed by treatment with
heliocin. The following is the best method to adopt :—Decolorize the
filaments by placing them in a 1 per cent. solution of chromic acid for
two days; add then to the solution 1 part in 2000 of the dye, and
shake slightly, so that it may dissolve equally. In an hour the
filaments will be ready for examination or permanent preparation.”
Indol as a reagent for Lignified Cell-membrane.*—Max Niggl
gives a résumé of the observations of previous observers on the use of
indol as a reagent for testing the lignified condition of the cell-wall,
supplemented with additional observations of his own.
If a section of a branch is treated with dilute hydrochloric acid,
and an alcoholic solution of indol added, the lignified cells acquire a
beautiful cherry-red colour, while the non-lignified cells of the cam-
bium, cortex, and epidermis remain uncoloured. The use of hydro-
chloric acid is, however, for several reasons inconvenient, and the
author prefers the use of dilute sulphuric acid of sp. gr. 1°2 (1 vol.
English sulphuric acid with 4 vols. water). The best mode of pro-
cedure is as follows:—Pure indol is dissolved in warm water. The
section is moistened with a drop of this solution, and covered with
a coyer-elass. The indol is then removed by blotting-paper, and a
drop or two of the dilute sulphuric acid run in. Wherever this
comes into contact with the indol which permeates the section, the
lignified cell-walls take a beautiful cherry-red, the sclerenchymatous
cells even a purple colour, which is retained by the preparation for a
considerable time. If the acid used is too concentrated, or the excess
not removed, the colour passes, after some weeks, to brownish red.
Among Thallophytes, Niggl found, by the use of this reagent, no
trace of lignification in alge, or in the majority of fungi; it was only
present in the cortical and medullary layers of a few lichens.
In vascular plants the cuticle is as a rule uncoloured by indol.
In many plants (contrary to the statement of other observers), the
walls of the guard-cells of stomata appear to be strongly coloured.
This is also the case with cork, except that in older cork-cells the
middle lamella gives indications of lignification. With very few
exceptions collenchyma also shows no colouring with indol. The
author enters into considerable detail with regard to the colouring of
the various elements of parenchyma, and of sclerenchyma. A charac-
* Flora, Ixiv. (1881) pp. 545-59, 561-8.
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 283
teristic property of tracheids is the very early and strong develop-
ment of lignification in their cell-walls. In the walls and disks of
sieve-plates, on the contrary, indol produces not the least reaction.
Protoplasm acquires a slight rose-colour with indol and sulphuric
acid, but no differentiation of the nucleus is observable ; the contents
of the stinging hairs of the nettle assume throughout a red colour.
No effect is produced on the contents of resin-passages.
The author concludes that the red colour imparted by indol and
sulphuric acid is an unfailing test for the lignification of the cell-
wall.
English’s Method of Preserving Hymenomycetes and Wild
Flowers.*—When we mention that the price of this book is 7s. 6d.,
and that each of the two sections only contains as much matter as two
columns of the Times, it will be obvious that it cannot be abstracted
without seriously interfering with its proprietor’s expected profits.
We therefore confine ourselves to generalities.
For Fungi, a double preservative compound is used, formed of
British farina, methylated spirit and corrosive sublimate, oxalic acid and
sulphur. There is also an “adjunct to the process,” formed of plaster
of Paris and sulphur, for imbedding the specimens after the preserva-
tive has been applied. The final process consists of varnishing.
Waxing and colouring can also be adopted if desired, for which
directions are given.
The process for flowers (which has only been tried for two years)
is to imbed them in plaster and lime as an absorbent, and gradually
heat them up to 100° F. After dusting, they are varnished with
similar varnish to that used for Fungi.
Mounting Salicine Crystals.t—Dr. D. H. Briggs recommends
the following process :—
Clean the slide perfectly with ammonia, thén rinse with hot water
and cleanse with ammonia again.
Add to the salicine from one-tenth to one-twentieth its weight of
pulverized gum arabic. Make a nearly saturated solution of the
salicine and gum in distilled water, or in ice-water heated to the
boiling point, and carefully filter the solution. Heat the solution to
100° C. in the beaker, and pour the hot solution upon a still hotter (sic)
slide, and drain off. Only a hot solution will give bright colours.
Hold the slide, and watch for disks of crystals. As soon as these
appear, place the slide on a cold iron block.
A rim is put on the crystals by another heating over the lamp and
another cooling on the iron. Without delay heat a drop of Canada
balsam on a circular cover-glass, and apply the cover to the crystals,
and fasten with white zinc cement on a turntable. ;
The process described, if followed with care, will yield most
* English, J. L.,‘A Manual for the Preservation of the Larger Fungi (Hymeno-
mycetes) in their natural condition, by a new and approved Method; also a new
Process for the Preservation of Wild Flowers.’ viii. and 41 pp. 8vo, Epping,
1882. i
y Amer. Mon. Micr. Journ., ii. (1881) pp. 227-8.
284 SUMMARY OF CURRENT RESEARCHES RELATING TO
excellent results; perfect rosettes cf crystals can be readily obtained,
giving brilliant effects with polarized light.
Bausch and Lomb Turntable.—We have no description of this
turntable, but so far as we can gather from the drawing (Fig. 59), it
Fic. 59.
differs from other turntables in being provided with a hand rest,
which can be adjusted to any convenient height.
Griffith Cell.*—Mr. E. H. Griffith places the slide on a turntable,
and with white-zine cement turns a circle on the centre if for a
transparent mount, or a disk if for an opaque one, then centres to the
circle or to the disk a common curtain ring, and immediately paints
the ring with the cement, taking care not to push it from its position.
When dry, the cement will hold the ring very firmly, so that there
need be no fear that it will break off.
If a shallow cell is desired the rings may be flattened easily ; or
if a deep one is required, several rings may be securely fastened one
above the other by painting each one in succession. If the cement
does not flow readily add benzole; and in case the cell becomes
rough, dip the brush in clear benzole and smooth it. Use a brush
well filled with the cement to secure a smooth background. With
a little practice a person may easily make fifty beautiful and practical
white cells in one evening, and in a few hours they will be hard and
ready for use. When the cover-glass is to be fastened, a little of the
* Amer. Mon. Micr, Journ., iii. (1882) p. 9.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 285
cement is easily applied. When dry, the slide may be finished with
colours prepared from tube paints mixed with benzole balsam, or
with dammar and benzole. Before mounting, if a dark background is
desired, a disk of asphalt of any desired size turned in the centre of
the ring will be found convenient. Over the asphalt a small-sized
cover-glass may be used for the object to be placed upon, or the
asphalt may be covered with shellac when dry. The object may be
fastened with gelatine or gum arabic, or made to adhere to the coat of
shellac before it becomes dry. )
Bausch and Lomb Circle Cutter.*—This instrument for cutting
circles of thin glass (Fig. 60) is intended to be attached to the
turntable, by means of the screw shown at the right of the figure, so
that the cutting point stands over the turning plate. The thin glass
is placed upon the turntable and held by the central pin which then
revolves with the glass. A gentle pressure causes the cutting point
to touch the glass, and perfect circles can thus be readily obtained.
Wax and Guttapercha in Dry Mounting.;—Prof. W. A. Rogers,
of Harvard College Observatory, writes: — Notwithstanding the general
condemnation of wax as a cement for covers in dry mountings, it is
doubtful whether the objections urged against its use are altogether
valid. I have had rather more than my share of experience in
unsuccessful mountings of this class. During the past five or six
years, I have been engaged upon the problem of the exact subdivision
of any given unit into equal parts. Whatever success I may have
gained in this direction has, I suspect, been somewhat more than
counterbalanced by the deterioration of the ruled plates through the
condensations which have formed under the covers.
“T have lately collected quite a large number of these plates for
the purpose of studying the characteristic defects of different kinds of
mountings. As the result of this study, I have reached the conclusion
that, for the most part, the primary cause of the condensations which
form under the covers, is the moisture remaining upon the glass after
the operation of mounting. No matter how thoroughly a glass slide
* Amer. Mon. Micr. Journ., ii. (1881) pp. 225-6 (1 fig.).
+ Ibid., p. 190.
286 SUMMARY OF CURRENT RESEARCHES RELATING TO
may be rubbed, if it is immediately held over a flame, a certain
amount of moisture will appear.*
“The evaporation from certain kinds of cement, without doubt
aggravates the difficulty, and probably this is, in some cases, the
independent cause of ‘sweating.’
“Nearly all of the slides examined were prepared in the following
way: First, the cover-glass being held in position upon the slide by
a clip, the moisture was expelled by heating. After the glass had
become sufficiently cooled, small bits of white wax were placed around
the edge of the cover-glass. The blunt point of a heated piece of
metal was then passed slowly around the cover, and the melted wax
flowed under it, far enough to hold it in position, The larger
number of the slides prepared in this way were found to be well
preserved. When, however, rings of cement were turned upon the
slides, the protection was in almost every case less perfect. In every
case in which shellac with anilin colouring was used, condensations
on the under side of the cover-glass were found. The covers of
several slides were removed, and in no case was there any sweating
found upon the surface of the slide.
“ About eighteen months ago, my attention was called to the use
of sheet guttapercha rings for dry mounting. My first experience
with these rings was not altogether satisfactory. It is now evident
that I did not, at first, apply sufficient heat to expel all of the
moisture between the cover and the slide.
“ After an experience of several months, I am convinced that
slides prepared in the following way, will remain in a perfect state of
preservation for any length of time. Use guttapercha rings having
a thickness of about one five-hundredth of an inch, and a diameter
about one-twentieth of an inch less than that of the cover-glass.
Hold the cover in position upon the ring with a light clip, while the
guttapercha is being melted by a gentle heat. If too much heat is
applied at first, the ring will lose its normal shape. After the gutta-
percha is thoroughly melted, the slide should be heated sufficiently
to expel every particle of moisture from under the cover. While the
slide is hot apply white wax to the surface, the melted wax will run
under the cover and will be stopped by the ring. After covering,
the wax can be removed from the surface of the glass with turpentine.
“JT shall esteem it a favour to be informed of any case in which a
ruled plate, mounted in this way, has failed to remain in good
condition.”
Aeration of Aquaria.—Mr. J. W. Stephenson points out that it
is impracticable to effectually aerate an aquarium in the way suggested
by M. Kiinckel d’Herculais, ante, p. 131. The only really effectual
method is to direct a very fine stream of water at a high velocity
obliquely upon the surface of the aquarium at about the distance of
an inch. By this means air in the finest possible state of subdivision
is carried some distance below the surface with the result of ensuring
a thorough aeration of the whole contents.
* But will not moisture always appear on glass placed over a candle or other
flame, through water being formed by the union of hydrogen with the oxygen of
the air ?—Ep.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 287
It was by this method that Mr. Stephenson was able to keep the
water in his marine aquarium so pure that (in 1867) he hatched
the spotted dog-fish and (in 1870) herring from the egg, which had
not previously been accomplished. The former was hatched at the
expiration of five months and nine days, and the latter of ten days,
after the eggs were placed in the aquarium.
The object of M. Kiinckel d’Herculais was apparently to devise
a means of aerating a marine aquarium by means of a fall of fresh
water, but the extra quantity of sea-water required to aerate an
aquarium in the way proposed by Mr. Stephenson is not likely to
present any difficulty, as it is easy to devise a plan by which a
constant circulation can be maintained between the reservoir and the
aquarium, without loss of water taking place.
Reference may also be usefully made to an article by Mr. C. J.
Watson on “a simple mode of aerating small marine aquaria,’ *
in which he also describes a method of injecting air by the fall of a
small quantity of fresh water.
Boyp, J.—How to Make Wax-cells.
[F. Barnard’s method, ITI. (1880) p. 860-1.]
Sci.-Gossip, 1882, pp. 59-60.
Britta, T.—Micro-fungi: when and where to find them.
North. Microscopist, II. (1882) pp. 15-16.
Bryan, G. H.—How to label Microscopie Slides.
[Instead of one thin paper label at one end, use two made of slips of thick
eard 1 in. by 3 to ? in.—they can then be placed one against the other
without the glass of one slide touching the cover of the next, and hence
there is no need of a cabinet, as any box of a suitable size will do.]
Sci.-Gossip, 1882, p. 64.
CrumpBateH, J. W.—Our Histological and Pathological Laboratories. II.
[Views as to what should constitute a good working laboratory. ]
Amer. Mon, Mier. Journ., U1. (1882) pp. 37-9.
Cunnincuam, K. M.—Cleaning Diatoms.
Amer. Mon. Micr, Journ., III. (1882) p. 14.
D., A. J.—Improvements in Turntables.
[Improvement by W. D. Smith in Kinné’s self-centering turntable—
explanation unintelligible. |
North. Microscopist, 11. (1882) pp. 74-5.
Ecer, L.—Der Naturalien-Sammler. Praktische Anleitung zum Sammeln,
Prapariren, Conserviren organischer und unorganischer Naturkérper. (The
Collecting Naturalist. Practical Guide to the Collection, Preparation, and
Preservation of organic and inorganic Natural Objects.) 5th Ed. 8yvo. Vienna,
1882, pp. iii. and 221. 37 figs.
Eveutsu, J. L.—A Manual for the Preservation of the Larger Fungi (Hymeno-
mycetes) in their natural condition, by a new and approved Method; also a new
Process for the Preservation of Wild Flowers. viii. and 41 pp. 8vo. Epping,
1882.
Hevrcet, H. van.—Immersion Fluids.
[Transl. of paper in ‘ Bull. Soc. Belge Micr” See Appendix.]
Amer. Mon. Micr. Journ., III. (1882) pp. 26-8.
Hey, W. C.—Pond-collecting in Mid-winter. ;
[Reports result of fishing some ponds near York on 2nd January.]
Sci.-Gossip, 1882, p. 31.
Laspeyres, H.—Ueber Stauroskope und Stauroskopische Methoden. (On
Stauroscopes and Stauroscopic Methods.)
Zeitschr. f. Instrumentenk., II. (1882) pp. 14-24 (3 figs.).
* Midl. Natural., iii. (1880) p. 270.
288 SUMMARY OF CURRENT RESEARCHES, ETC.
Matsrancur, A.—Réactifs pour Vétude des Lichens. (Reagents for the
study of Lichens.) Rev. Mycol., TV. (1882) pp. 9-10.
Microscopic Curiosity.
[Working steam-engine so small that a thimble will cover it. ]
Amer. Mon, Mier, Journ., IIL. (1882) p. 19.
Mounting Class of Manchester Microscopical Society.
[Report of meeting. ]
North. Microscopist, II. (1882) p. 40.
Niect, M.—Das Indol ein Reagens auf verholzte Membranen. (Indol, a
Reagent for Lignified Membranes.)
(Abstr. of original article in ‘ Flora, LXIV. (1881) pp. 545-59, 61-6.]
Bot. Centralbl., IX. (1882) pp. 284-5.
Reinscu, H.—Detection of Borie Acid, Silica, and certain Metals by means of
the Microscope. Journ. Chem. Soc., XLII., Abstracts, (1882) p. 245,
from Ber. Deutsch. Chem. Soc., XIV. 2325-31.
S., W. J.—Mounting for Hot Countries.
(Inquiry for hints as to mounting in Canada Balsam and Dammar Varnish
in India, and statement of difficulties experienced. ]
Sci.-Gossip, 1882, pp. 39-40.
Semper, C.—Bemerkungen zu Herrn Dr. Riehm’s Notiz “ Kine neue Methode
der Trockenpraparation.” (Remarks on Dr. Riehm’s note on “a new method of
dry preparation.” Zool. Anzeig., V. (1882) pp. 144-6.
Stocker, G.—Preserving Flowers. Sci.-Gossip, 1882, pp. 65-6.
STowELL, C. H.— Laboratory Notes (contd.).
[Examination of sputa in suspected cases of phthisis, &c.]
The Microscope, I. (1882) pp. 172-4 (1 fig.).
Vorce, C. M.—The Detection of Adulteration in Food. V. Red-pepper and
Turmeric. VI. Butter.
Amer. Mon. Micr. Journ., III. (1882) pp. 1-6 (1 pl.) pp. 21-3 (5 figs.).
Watmstey, W. H.—Some Hints on the Preparation and Mounting of Micro-
scopic Objects. 2nd paper.
[Mounting in balsam in cells. ]
The Microscope, I. (1882) pp. 161-72 (7 figs. ).
Warvd, E.—Micro-erystallization.
[Describes the mode of preparation of Micro-crystals. ]
North. Microscopist, II. (1882) pp. 25-33.
Waite, M. C.—Examination of Blood-stains by Reflected Light.
[ With Beck’s (vertical ?) illuminator and + in. objective. ]
Amer. Mon. Micr, Journ., I11. (1882) p. 6.
Wicurman, G. J.—Crystallized Fruit Salt.
[Recommended as an object for the Polariscope.]
Sci.- Gossip, 1882, p. 64.
Woronin, —.—Les meilleurs Liquides Conservateurs pour les Préparations
Microscopiques. (The best preservative liquids for microscopical preparations.)
Rev. Mycol., TV. (1882) p. 71.
ZIMMERMANN’S (O. E, R.) Mykologische (mikroskopische) Praparate. (Myco-
logical—microscopical—preparations. )
{General description by G. W.] Ls
Hedwigia, X XI. (1882) p. 5.
( 289 )
PROCEEDINGS OF THE SOCIETY.
Awnnuat Meetine oF 81H Fesrvuary, 1882, ar Kina’s Cottear, STRAND,
W.C., THe Presipent (Proressor P. Martin Duncay, F.R.S.) mn
THE CHAIR.
The Minutes of the meeting of 11th January last were read and
confirmed, and were signed by the President.
The List of Donations (exclusive of exchanges and reprints)
received since the last meeting was submitted, and the thanks of the
Society given to the donors.
From
Reinsch, P. F.—Neue Untersuchungen iiber die Mikrostruktur
der Steinkohle des Carbon, der Dyas und Trias. viii. and
Ie pp.and 94 pls. ,4to. -Meipzig; 188.5 3) 3. oe 2 Yr Crisp:
Tris-Diaphragm for Objectives .. .. .. «2 «ee . Mr. C. Collins.
Sections of Sugar-caneand Palm .. .. .. .. .. Dr. B. W. Richardson.
The President, referring to Professor Reinsch’s book, said it would
be very desirable to have the mounted specimens which had been
promised by him.* Without these it was impossible to determine
whether the conclusions at which he had arrived were correct.
Mr. Crisp said that with regard to Dr. Richardson’s slides it
‘should be noted that the processes which he quoted as having been
devised by Dr. Stirling were in reality due to Dr. H. Gibbes, whose
descriptions had been taken by Dr. Stirling without acknowledgment
of their original source.
Mr. Crisp also called attention to the Iris-diaphragm for objectives
presented by Mr. C. Collins. The use of such a diaphragm had been
originally suggested by Dr. Royston-Pigott, but was now revived by
Mr. G. E. Davis, for the special purpose of obtaining penetration
with wide-angled objectives by reducing their aperture (see p. 262).
The Treasurer, Dr. Beale, F.R.S., read his statement of the
income and expenditure of the Society for the past year, which had
been duly audited by the Auditors appointed at the last meeting
(see p. 292). ;
Dr. Gray moved that the statement be received and adopted; and
Mr. Michael having seconded the motion, it was put from the
chair and unanimously carried.
A vote of thanks was given to the Treasurer and the Auditors.
; The President, in pursuance of notice given at the previous
meeting, read the proposed alteration in the Bye-law relating to the
payment of subscriptions. He thought the alteration was one which
would commend itself to the Fellows.
Mr. Crisp then moved that the words from “ Fellows” to “ year ”
* See Journal, i. (1881) p. 712.
Ser. 2.—Vot. II. U
290 PROCEEDINGS OF THE SOCIETY.
inclusive be omitted from Bye-law No. 6a,} and the following inserted:
— «A Fellow elected in any month subsequent to February shall not,
“however, be called upon for the whole subscription for the current
“year, but for a proportional part thereof only ; that is, if elected in
“March or April he shall pay one pound fifteen shillings, in May or
“ June one pound eight shillings, in October fourteen shillings, or in
“ November or December seven shillings.”
This was seconded by Mr. T. Charters White, and carried.
The Report of the Council was read by the President (see p. 293).
Mr. T. Charters White moved that the report be received and
adopted and printed in the usual way, and the motion having been
duly seconded, was put to the Meeting, and carried unanimously.
The List of Fellows proposed as Officers and Council for the
ensuing year was read as follows :—
President—Prof. P. Martin Duncan, M.B., F.R.S.
Vice-Presidents—Prof. F. M. Balfour, M.A., F.R.S.; *Robert
Braithwaite, Esq., M.D., M.R.C.S., F.L.S.; *Robert Hudson, Esq.,
F.RS., F.L.S.; John Ware Stephenson, Esq., F.R.A.S.
Treasurer—Lionel 8. Beale, Esq., M.B., F.R.C.P., F.R.S.
Secretaries—Charles Stewart, Esq., M.R.C.S., F.LS.; Frank
Crisp, Esq., LL.B., B.A., V.P.L.S.
Twelve other Members of Council —*Ludwig Dreyfus, Esq. ;
Charles James Fox, Esq.; James Glaisher, Esq., F.R.S., F.R.ASS. ;
*J. William Groves, Esq.; A. de Souza Guimaraens, Esq.; John E.
Ingpen, Esq.; John Mayall, Hsq., jun.; Albert D. Michael, Esq.,
F.L.S.; *John Millar, Esq., L.R.C.P. Edin., F.L.S.; *William
Thomas Suffolk, Esq.; Frederic H. Ward, Esq., M.R.C.S.; T.
Charters White, Esq., M.R.C.S., F.L.S.
Mr. Beck and Dr. Gibbes having been appointed Scrutineers, pro-
ceeded to take the ballot, and subsequently reported that the above-
mentioned Fellows were all duly elected. A vote of thanks to the
Scrutineers was unanimously carried.
Mr. Beck said it had been usual to regard a vote of thanks to the
Secretaries as a matter of course, but he thought that at no previous
time did they so much deserve that a hearty vote of thanks should be
offered to them. The Society was very greatly indebted for their
services, and it was not as a mere matter of form that he made the
' proposition that they should be thanked for the able manner in which
the business of the Society was conducted.
The President thought there could be no difference of opinion
upon this matter. The Secretaries were the very life and soul of the
Society, and most heartily deserved their thanks. The motion was
then put from the chair, and carried by acclamation.
Mr. Crisp in returning thanks for the vote on behalf of himself
t+ See Journal, iii. (1880) p. 736.
* Have not held during the preceding year the office for which they were
nominated.
PROCEEDINGS OF THE SOCIETY. 291
and his co-secretary, said that he felt there should be an amendment to
the proposition so as to make it include the President and the other
Officers of the Society instead of singling out the Secretaries alone. The
President in particular had been most indefatigable in the attention
which he had given to the affairs of the Society, and had especially
distinguished himself by the way in which he had added by his
comments to the interest of the matters brought before their meetings.
There was he knew a very general desire that his term of office might
be an extended one.
The President then read his Annual Address, which was warmly
applauded by an appreciative audience (see p. 145).
Mr. Ingpen said he had much pleasure in proposing a vote of
thanks to the President for his able and interesting address. He was
sure that those who had followed the revival of the discussion of the
aperture question would thoroughly agree that the last year had, as
the President had observed, marked an important epoch, in that it had
placed the matter on its true scientific basis, and had exposed the
strange fallacies by which the previous consideration of the subject
had been confused. The Address was one which he felt sure they
would all be pleased to read when printed, and to remember. For his
own part, he would venture to express the hope that the President
would carry out his intention of continuing his record of progress in
a similar manner at a future time.
Dr. Braithwaite having seconded the motion, Mr. Ingpen put it
to the Meeting, and declared it carried by acclamation.
The President thanked the Fellows for the vote of thanks and
also for the honour which they had done him in again electing him
President. He had at first been doubtful as to how he should succeed
in that office, for although he had occupied the Chair in other societies,
he had been prevented from attending the meetings of this Society.
He could only say that he would do his best during the term of office
for which they had re-elected him, and hoped that at its termination
he should receive their approval.
New Fellow.—Mr. W. A. Thoms was elected an Ordinary
Fellow.
SOCIETY.
PROCEEDINGS OF THE
292
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PROCEEDINGS OF THE SOCIETY. 293
REPORT OF THE COUNCIL
presented to the Annual Meeting on 8th February, 1882.
New Fellows.
Having regard to the large number of new Fellows elected during
the years 1879 and 1880, it might have been fairly expected that the
new elections would now show some diminution. The Council are,
however, gratified to find that during the past year 51 Ordinary
Fellows were elected, as against 47 in 1880 and 58 in 1879.
Twenty-four Fellows have died or resigned (1 compounder,
22 subscribers, and 1 Honorary Fellow), and the list now stands as
follows :—501 Ordinary, 49 Honorary, and 83 Ex-Officio Fellows.
The greatest number of Ordinary Fellows at any previous period
of the Society’s existence was 452.
Finances.
The income of the Society (excluding admission fees) now amounts
to 728/., being 636/. 6s. derived from subscriptions, and 91/. 14s. from
investments. In accordance with the determination come to at the
Annual Meeting in 1881, it is not intended in future to invest Com-
positions, except in the contingency mentioned in the Council’s last
Report.
Library, &c.
The additions to the Library are now so numerous that there is a
difficulty in providing space for them on the shelves, and it is feared
that the only remedy will be to discontinue some of the exchanges.
A catalogue of the Library has been prepared by the Assistant-
Secretary, and checked by Mr. Fox, who has also kindly undertaken
to prepare a catalogue of the property of the Society generally.
Meetings.
The attendance at the meetings of the Society has been well main-
tained, and if the Council were furnished with a greater number of
papers, recording the results of original work on the part of Fellows,
the position of the Society would leave hardly anything to be
desired.
The Journal.
In accordance with the desire expressed by the Council, the last
volume of the Journal has been somewhat reduced, and would have
been brought within the limit of 1000 pages but for the pressure
caused by the revived discussion of the aperture question.
With the completion of that volume Mr. Crisp’s arrangement for
the honorary editorship of the Journal terminated. The Council
“passed a unanimous resolution expressing their thanks for his
valuable services in conducting and editing the Journal, and for the
great liberality he had displayed in its production. Under the
‘
294 PROOEEDINGS OF THE SOOIETY.
special circumstances which existed, the Council did not feel them-
selves able to invite Mr. Crisp to continue to act as Editor; but
having appointed a committee to confer with him on the subject, they
were gratified to find that he was willing to continue the existing
arrangement for two years further. The Council are sure that the
Society will cordially endorse both their resolution as to the past
conduct of the Journal and their satisfaction that it will be continued
for a further period. ‘The thanks of the Society are also due to the
Associate Editors for their services in connection with the Journal.
Mertine or 8rx Marcu, 1882, ar Kine’s Cotter, Srranp, W.C.,
Tue Presmenrt (Proresson P. Martin Dunoan, F.R.S.) in
THE CHAIR.
The Minutes of the Annual Meeting of 8th February last were
read and confirmed, and were signed by the President.
The List of Donations (exclusive of exchanges and reprints)
received since the last meeting was submitted, and the thanks of the
Society given to the donors.
Arnold, J. A. F.—Die neueren Erfindungen und Verbesserungen From
in betreff der Optischen Instrumente. 232 pp. and 4 pls..
(hoy, “Qyaralllinnorsiven, ISES)55 fA) eg 66 soo on ot Mr. Crisp.
Diatomaceous Earths from California .. .. .. .. .. Mr. H, G. Hanks,
The President said that the Council had approved (under the
15th Bye-law) the recommendations of two Honorary Fellows to fill
the vacancies in the list caused by the deaths of Messrs. Schleiden and
Schwann, viz. (1) M. C. Robin, of France, well known as an histologist
and microscopist, and the author of the ‘ Traité du Microscope et des
Injections’; and (2) Dr. L. Dippel, of Germany, also an eminent
microscopist, and the author of ‘Das Mikroskop und seine Anwend-
ung, in which not only the Microscope but the histology of plants
is ably dealt with.
Mr. J. Mayall, jun., described Wenham’s Universal Inclining
and Rotating Microscope exhibited by Messrs. Ross (see p. 255).
Mr. Crisp exhibited and described the Bausch and Lomb Optical
Company’s Trichinoscope (see p. 258); the “ Hampden” Portable
Simple Microscope, lent by Sir John Lubbock, Bart. (see p. 258) ;
two cheap American “ Dissecting Microscopes”; one of Fasoldt’s
19-band test-plates; Aylward’s “ Patent Micro-slide”; and Stokes’s
Tadpole-slide (see p. 110).
Mr. R. J. Lecky’s note as to the origin of the glutinous character
of spiders’ webs was read.
Mr. Crisp described the composition of the two immersion fluids
sent by Dr. Van Heurck, and exhibited at the December meeting (see
pp. 183 and 264).
PROCEEDINGS OF THE SOCIETY. 995
Dr. Ord described and figured on the black-board certain sym-
metrically-placed large nerve-fibres which he had discovered in the
spinal cord of the pike, the axis-cylinders of these animals being of
enormous size, at least seven or eight times the diameter of the largest
axis-cylinder found in the human spinal cord, or so far as is known
in any of the higher mammalia.
Mr. Stewart said that the presence of the large fibre described by
Dr. Ord with its proportionately large axis-cylinder was a matter of
considerable interest, and that he looked forward to Dr. Ord’s further
investigations, so that its connections might be determined and data
derived for understanding its chief function.
The President said they were greatly indebted to Dr. Ord for his
description and drawings, and expressed the hope that he would be
able to lay before them during the present session the results of his
further investigations so that they might be published in proper
- form.
Dr. Ord, in reply to a question as to the way in which he prepared
the cords referred to, said that they were partly prepared with strong
spirit, and partly with Miuller’s fluid with a considerably long immer-
sion. For those that he was now preparing he used a bichromate of
ammonium solution.
Mr. Crisp referred to the objection that had been raised to homo-
geneous-immersion objectives as regards their liability to be scratched
(see p. 264).
Dr. Edmunds said that he had used homogeneous lenses from
their earliest introduction, and that the surfaces of the front lenses
were still as highly polished, and the objectives in fact in all respects
as perfect now as they were at first.
Dr. A. S. Mercer’s views as to stereoscopic vision with non-
stereoscopic binocular arrangements were explained by Mr. Crisp
(see p. 271).
Mr. Stewart described and exhibited a gold-stained preparation
of the crop of a snail, showing the nerve-termination having occa-
sional large nerve-cells (in groups of rarely more than two) connected
with it. From these large fibres spring, and there were others much
smaller with groups of nerve-cells, from which again proceeded
fibres of exceeding minuteness, forming a dense intercommunication
with a few mostly elongated nerve-cells connected with them. The
latter was apparently the terminal nerve-plexus, and lay immediately
beneath the epithelial lining of the pharynx.
The President said he was grateful to Mr. Stewart for so inte-
resting a demonstration, which opened up a field well deserving the
attention of some of the younger Fellows.
Mr. Stewart said that he did not in these experiments recognize
the termination in the muscle-fibres, but that some of them do so
there was no doubt.
2.96 PROCEEDINGS OF THE SOCIETY.
Mr. Crisp, referring to a paragraph in the President's Address,
explained the misconception involved in the use of miniatured images,
so far as regards the supposition that thereby very minute fractions
of an inch were visible.
The President announced that the Second Conversazione of the
session would be held on the 26th April.
The following Instruments, Objects, &c., were exhibited :—
Mr. Bolton :—Various Rotifers.
Mr. Crisp:—(1) Bausch and Lomb Optical Co.’s Trichinoscope
(p. 258). (2) Two cheap American “ Dissecting Microscopes.” (3)
Fasoldt’s 19-band Test-plate. (4) Aylward’s “ Patent Micro-Slide.”
(5) Stokes’ Tadpole Slide (p. 110).
Sir John Lubbock, Bart.:—The “Hampden” Portable Simple
Microscope (p. 258).
Dr. Ord :—Preparations illustrating his paper.
Messrs. Ross:—Wenham’s Universal Inclining and Rotating
Microscope (p. 255).
Mr. Stewart :—Pharynx of snail.
New Fellows.—The following were elected Ordinary Fellows :—
Messrs. William A. Delferier, Wilson Noble, and Charles N. Peal.
Water W. Reeves,
Assist.-Secretary.
fay OU 1S ISU UN Une seconGd weanesaay or
February, April, June, August, October, and December.
Ser. II. To Non-Fellows,
3 Evel. II. Part 3. JUNE, 1882. i Price 4s.
JOURNAL
z OF THE
ROYAL
CONTAINING ITS TRANSACTIONS AND PROCEEDINGS,
AND A SUMMARY OF CURRENT RESEARCHES RELATING TO
5 ZOOLOGY AND BOTANYDT |
Ee (principally Invertebrata and Cryptogamia),
- MICROSCOPY, éc- |
Ldited by
FRANK CRISP, LL.B., B.A., 7
One of the Secretaries of the Society
and a Vice-President and Treasurer of the Linnean Society of London ; |
-- -\ WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND
4 BOW, BENNETT, M.A., B.Sc., - F, JEFFREY BELL, M.A,
r Lecturer on Botany at St, Thomas's Hospital, Professor of Comparative Anatomy in King’s College,
§. O, RIDLEY, M.A., of the British Museum, asp JOHN MAYALL, Joen.,
a FELLOWS OF THE SOCIETY.
i |
:
s
nee WILLIAMS & NORGATE, 3
Be LONDON AND EDINBURGH. Sei, oy MEL
Fo
; a - : “ : <
a BY WM. CLOWES AND SONS, LIMITED,] = [STAMFORD STREET AND CHARING CROSS.
er
iia
2.)
JOURNAL
OF THE
ROYAL MICROSCOPICAL SOCIETY.
Ser. 2.—VoO.L. II: PART 8.
(JUNE, 1882.)
CONTENTS, 9 a
TRANSACTIONS OF THE SoClETY—
VIL.—Nore on THE SPICULES FOUND IN THE AMBULACRAL TUBES OF —
THE REGULAR Honinomes. By Professor F. Jeffrey Bell,
MLAS PRIMES CPA N 2) (76 Gee Ae ot, eee nl oe ee
VIII.—Tue Reation or APERTURE AND PowER IN THE Microscope.
By Professor Abbe, Hon. F.R.M.S.
1X.—Tue Bacrerta or Davarye’s Suptrommta. By G. F. Dowdes- ints
well, M.A., FLR.MLS., F.C.S., &e. 4.0 6. ee a a
Summary. oF CURRENT RESEAROHES RELATING TO ‘ZooLOGY AND
Borany (PRINCIPALLY INVERTEBRATA AND CrYPTOGAMIA), Micro-
scopy, &c., INCLUDING ORIGINAL COMMUNICATIONS FROM Funtows :
AND “OTHMBE So as cp Bed sevens Ain ad TE Vee ace
PAY : $a. Seah
Germinal Layers'of the Chick... ° 402 soo: Gen e's gs eh et ae
Development of Lepidosteus a6 wine aa 0 8 ee ale ee
Spermatogenesis in Vertebrates and Annelids BS. OS Ea We PEO
Cell-structure S Bee Aeshna slat od ae A RO
Theory of Ameboid Movements... Re ores TR eae Piney ee
Distinctions between Organisms and Minerals... :
“ Symbiosis of Animals with Plants”—Chlor aphylicorpuscles and Aint
Deposits of Spongilla and Hydra
Palzontological Significance of the Tracks of Different Invertebrates . ae $ oe
Lymph of Invertebrates... Bera ree ee Hommes ec geen
“Development of the Cephalopoda do hee gc ae eh eee ae
_ Development of the Oyster... Ripard tee er ctr tie
Abortion of Reproductive Organs of | Vitrina xe Boe t Rane sae
Morphology of the pata ce he Pee pipe TG Say ehon co
New Synascidian.. .: CR hee eee he esehaeeanas
Alternation of Generations in Doliolum ..: ©. NSPE Stee: Orta! PS
Nervous System of the zene Hé NES Rw ence ier eh
Occident Ants .. Pile Ge akan Maa thas ty de Se
Pycnogonida eee oe se ae os ee NAS sR hs : os a ye
Spithers? Webs 5 ico ete Ss Ree ae gees Ta ra re oe Sa bo
Limulus a Crustacean... Oe SSR ee ee A a
Segmental Organs in Tsopoda comer PEP MAA? A Abe eae ee aT tT
Bopyridz oo Sr rat 8 wee se Ke 2,
Peculiar mode of Cop ulation in Mamie Dendroowia teeta Se ea g
Classification of the Not aiokcaduben? Baek Caer Reece ee Th
Relations of the Platyhelminthes .. 4. eeu te
Entozoa confounded with Trichin# .. se) us as ue ae ne os
Life-History of the Liver Fhike 0. 2000 ne ae be a
Excretory Apparatus of rains Geiicclage sated eee a hes ea
_ New Parasites .. odo doh pega eg Pokal ORS te seal ace
(3)
Summary or Current Researones, &c.—continued.
~ Tube of Stephanoceros Hichorntt = .. 1s sn ne ae en
Structure of Pedicellariz ME CPSs LRN PAA Dee
Circulating Apparatus of Starfishes.. ane Pr eh Cony teas Pre are tae N
Genital Passage: of Asterias Apc PER EON Peeps OTTey adler
Chaculsnta Pron pende. cece fan fee op node uae Kes, Se ah wee
Sponges of the Gulf of Triest .. 1 vee ue ne ne
Spongiophaga in Fresh-water Sponges SRcanee Pina Na paler shoe
Neto Fresh-water Sponges... 15 ve es be ne) hw oe) ee
Organization of the Cilio -flagellata Fe apron Ma GLEE SP ae
Infusorian with Spicular Skeleton 1. oe ss ne ees
Contractile Vacuole of Vorticella .. 10 a0 es ae oe
* Geographical Distribution of pees: A cer ue eA Sea
Classification of the Gregarimda .. Ponce see DCs
_ Psorospermiz in Man,, +6 ss 8 as ss
Myxosporidia _.. a
Morphology of Protozoa A ener sie elu, fata
TLGZO0T CANAACNEE ina Se en Paw Na Bakes
Borany.
Ghorecal Difference between Dead and Living Protoplasm ..
Occurrence of Aldehydes in Chlorophyllaceous Plante .. ..
~ Organ not hitherto described in the Vegetable Embryo ..
Studies of Protoplasm.. .. i
Composition of the Protoplasm of Zthalium septicum ss
Properties of the Protoplasm in Urtiea- urens. ,
Fertilization of Salvia splendens ..- ss once wen
Reproductiwe Organs of Loranthacee .. .. Spectres
- Structure and Mode of Formation of Spermatozoids Gat atte eas
Cell-nucleus in the Mother-cells of the Pollen of Liliacee §.. ,.
Crystalloids in the Cell-nuclet of Pinguicula and Utricularia
_ Cystoliths in Momordica wt Slaw imme a eee Tee cig ‘i
Sphero- crystals
‘Structure of Starch-grains.. Pes IU gee 2 ss
Assimilating Tissue... Reo Se iene ce Dy
Fibrovascular Bundles of Monocotyledons Wa wince ec Wienges
Steve-Tubes .. SP, Nacerihygx PeNT nS Morpeth
Structure and Functions of Stomata.. .. sevineekg cea tatas
Stomata of Stapelia: ..
Influences of External Forces on the Direction of Growth
Water Distribution in Plants .~. Boh ont creat
Causes of the Movement of Water in ‘Plants - =
* Compass-flowers”
_ Relation of Nutrition to # the Distribution of the Sexual Organs 0
Prothallium of Ferns...
- Cell-division and Development of the Embryo of Isoctes lacustris...
Chemical Composition of Mosses
Influence of Oxygen on the Deoslupiituno} of the Lower Fungi a
~Chetomium ..
- . Completoria complens, a Parasite on the Prothaltium m of Ferns
' Rehm’s Ascomycetes ..
~ Destruction of Insects by Yeast .. ;
Development of Fungi on the Outside and Inside of Hens’ Eqge ..
Biology of Bacteria
Influence of Concussion on ‘the Development of the Schizomycetes ..
Experimental Production of the Bacteria of the Catile-distemper ..
Bacteria of Caticasian Milk Ferment — .. 20 un os
Parasitic Organisms of Dressings ... 2. 2. se tnt
_ Parasitic Nature of Cholera... ke
POPU GHSANE OF LWUEPCUNOREE Wace? twas noo oe su, fae eee ae py oe
BHaperimental:Puberctslosia is 2 tre sas vai ob ae awd tk
Etiology of Tubercular Disease... a
Structure and Development of the A pothecia. of Lichens a
Structure of Crustaceous Lichens .. Caio tga s weaetias
nogonium and the Schwendenerian Theory . ESA ers awed aero
eee aie ol Marne Ale Riaiat antic lane iam i OR any ree e tiea
ve
C2
Summary or Current Reseancurs, Soa
Phyllosiphon Arisari Bas geo tWas sad 3 6h) aa. awe en cone eae po eee ene
Structure of Corallina “ eee
Impurities of Drinking Water caused d by Vegetable Growth. 4. a
Fossil Siphone® ..... Das eas eed OES. GE ee
oP alivehbeniy a Abaya es oO TE ras eae aes Ge abs ee ee
Motion of Diatoms bi Mpeg det FPR ee pee oe eee
Microscopy.
Griffith's Portable Microscope .. rates niet re re aie eee a st
Parkes’ Class Microscope (Fig. 61) . wok od Dee Ree re
Pringsheim’s Photo-chemical Microscope (Fig. 62) Ee
Waechter’s (or Engel’s) Class or Demonstrating Mieroscope Figs 6 63 J aad o4
Wasserlein’s Saccharometer Microscope (Fig. 65)... Sa 39
Wenham’s Universal Inclining and Rotating Microscope bs acs eee
Briicke Lens.. —.. SS Aes
Bausch and Lomb Handy Dissecting “Microscope (Fig. 86). jae Ste
Excelsior Pocket and Dissecting Microscope (Fig. 67) .. Aes i
Hartnack’s Drawing Apparatus (His’s Embryograph) ig: 88) «. aT aes
Drawing from the Microscope .. i.
Ulmer’s Silk Thread Movement (Figs. 69-72). ;
Diaphragms for Limiting the Apertures of Objectives (Fig. 73):
Correction-adjustment for Homogeneous-immersion Objectives .. +«. v
Hitcheock’s Modified Form of Vertical Illwminator ... «1 we te
Flesch’s Finder (Figs. 74 and 75) .. .. Tei Pe yise site
Burnett's Rotating Tive-Box .. ae sae Cag ope Ree
Schklarewski’s Hot-water Stage (Fig. 76). Bk? i Sp ea ne ee eee
Abbe’s Condenser (Figs. 77. and 78) s.0 <5 6.) weve be ee ae
Bausch and Lomb's Immersion Illuminator 2. 0s ss eee es?
.
. *
Bausch’s Paraboloid .. Es Sek a hoe IR eee ee
Browning’s Simple Heliostat (Fig. 79) Pa pe ata a a
Hayem and Nachet’s pear Hematometer (Figs 80-82)... paca eras
Fasoldt’s Test-plate .. -. Sea pier ys. e. ess
High Resolving-power. 0.40 ek 68 te ae ae ee oe ie
Binocular Microscopes . Sway ges OREN he EY ae Opes Mura Pe ae oe Sek Ny:
Electric Light in Microscopy PR REMY Ce ate hoe whe
Definition of Natural and Artificial Objects fe ihtaper i Sire heey eas kee name
Cole’s “ Studies in Microscopical Science”. ws su te ue eae ae
Journal of the Postal Misroscopical Society... 9 +6 32 ae ne ene
. Colouring Living Microscopical Organisms .. Ree Ree
Mounting Histological Preparations with Carbolic “Acid and Balsam... Fee
Differentiating Motor and Sensory Nerves... «ss ee se Pee
Preparing Nerve-fibrils of the Brain -. wu ce tenes 2 one
Cochineal. Carmine-solution .. apace gine eaet ae tale
Polarized Light as an Addition to Staining 9 Rei eh OM hae ce
Wickersheimer’s Preservative ee Dele ?s eon ies feng Sot ere om
Preparing Hemoglobin Crystals’ - pai mgt oo eae boar Cae
Preserving FONG se oe ae SA Ra Lee th Oe e:
Cleaning Diatoms * oe oe A on ee epg ee, o* Sa o-
Gaule’s Method of’ Imbedaing eae ¥%
Williams’ Freezing Microtome adapted for Use with Ether ig. 88) ee _ £30
Swift and Son's Improved Microtome (Bigs. 84-87) +. swe be ae
Bausch and Lomb’s Standard Sey-Cntering iahiowi As Skene alae ide
Orystallized Fruit Salt 3.0 ve ss, be tigiet See Owes emus
Proorepines. or THE Socery =.) ake os
conN
or
NS
Royal Alicroscopical Society.
IMBETINGS FOR 1882
Av 8 P.M.
1882. Wreednestsy, JANUABY {20 Sortie oy ciate Ss eo LE
Ge FEBRUARY .. yy Serine
(Annual Meeting for Election of Ofte cers
and Council.)
is ae A MAROR ee ce Se San ee Ria ee
Bs ng i APR ee Toa CO alge pega ee
es Mawes ee ee eee a, NO
5 SEN OE ag oe it Ne
dont: OUTOBER Be ete eet as © oe ge eC ©
: ‘ey AINE CW OBR 5 Se een ag I A) aR
: Hs ADRURMBRR 15 8 oes eek a eee de
“THE Be SOCIETY ” STANDARD SCREW.
The Council have made SE I for a further supply of Gauges
: and Screw-tools for the “Soomry” Stanparp Screw for Oxszorives,
ue The price of the set (consisting of Gauge and pair of Screw-tools) is
_ 12. 6d. (post free 128, 10d. ). Applications for setis should be made to the
> Assistant-Secretary. |
o For an explanation. of the intended use of the cane, see Journal of the
Pads pees PP. fase 9
ue _ ADVERTISEMENTS FOR THE JOURNAL.
; Mn. Ceanes piace of 75, Chancery Lane: W.C., is the authorized
Agent sas Collector for Advertising Accounts on behalf of the Society.
8.9
COUNCIL.
ELECTED 8th FEBRUARY, 1882.
PRESIDENT.
Pror. P. Marti Duncan, M.B., F.B.S.
VICE-PRESIDENTS.
Pror. F. M. Baurour, M.A., F.RS.
Rozert Brarrnwaite, Esq., M. D., M.B.CS., F.LS.
Rosert Hunson, Esq., F.BS., FLS.
Joun Ware SrepHenson, Hsq., F.R.A:S.
~_
TREASURER.
Lionet §. Beatz, Esq., M.B., F.R.C.P., FBS.
SECRETARIES,
Cuartes Srewart, Esq., M.R.CS., F.LS.
Franx Case, Esq, LLB, BA, VP. & Tams. LS,
Twelve other MEMBERS of COUNCIL. —
Lupwie Dreyrvs, Esq.
Cartes Jamus Fox, Esq.
James GiaisHer, Esq., F.RS., F.RAS.
J. Wu11am Groves, Esq.
A. pE Souza Guimararns, Esq.
Joun E, Inapen, Esq.
Joon Mayan, Esq., Jun.
Apert D. Micnazn, Esq., F. L. S.
Joun Muar, Esq., L.R.C.P.Edin., ELS.
Witx1Am Tuomas Surroxx, Esq.
‘Freverice H. Warp, Esq., M. R. CS.
T. Ouaxrens Wie, Eg, MROS, PLS. :
ule ae Nig oi Fe > fee ps
SP NE SR ae PRT a
PSI, OD Sen A EOS
- '% J
iy UP Mae re
Sy Sens a Mla Sy | Sy
Lee)
I. Numerical Aperture Table.
The “ APERTURE” of an optical instrument indicates its greater or less capacity for receiving rays from the object and
transmitting them to the image, and the aperture of a Microscope objective is therefore determined by the ratio
between its focal length and the diameter of the emergent pencil at the plane of its emergence—that is, the utilized
_ diameter of a single-lens objective or of the back lens of acompound objective.
[his ratio is expressed for all media and in all cases by m sin u, n being the refractive index of the medium and wu the
semi-angle of aperture, ‘The value of n sin w for any particular case is the ‘‘ numerical aperture” of the objective,
Be - Diameters of the
Pepe Angle of Aperture (= 2 u). ; Theoretical Pane?
Wace Lees of ations | seu mmerical| | waim. |Gomapmone| ne | RRMME | wating
Bea ces ; d Aperture. Dry ater- | Homogeneous-, nating | _— Power, in Powen
Objectives of the same (n sin u=a.) | Objectives Immersion, Immersion | Power. | Lines toan Inch.)
» _~ Power (4 in.) Spee: uect 5 * | Objectives.| “Objectives. | (a2.) | (A=0°5269 p (-)
from 0°50 to 1-52 N. A, = }) a= 1*33.), (m = 1752) | =line E.) | a
|
1°52 |. 180° - 0/°| 2°310) 146,528 "658
-. 1°50 HSE GLE De | 2°240 | 144,600 *667
- 1°48 | 153°: 39" | 2-190) 142,672 *676
1-46 | 147° 42’ | 2-132| 140,744 | +685
1°44 142° 40’ | 2°074 138,816 694
1:42 oe 138° 12’ |2°016|- 136,888 “704
1°40 | oe 134° 10’ |1°960| 134,960 "714
1°38 ee 130° 26’ | 1-904 133, 032 *725
1:36 126° 57’ | 1-850 131,104 “735
1°34 5 123° 40’ | 1°796 129,176 “746
1°33 180°. 0’; 122° 6’ |1°770) 128,212 *Td2
1°32 165° 56’| 120° 337 /1°742 127,248 “758
1°30 155° 38’) 117° 34’ | 1°690 125,320 -769
1:28 148° 28'| 114° 44’ |1°638) 123,392 *781
1°26 142° 39’| 111° 59’ | 1°588 121,464 “794
1:24 137° 36’; 109° 20’ | 17538 | 119,536 *806
1:22 Ba 138° 4’| 106° 45’ | 1-488 117,608 *820
1°20 oe 128° 55’) 104° 15’ | 1-440 | 115,680 *833
LAG | Sad 125°. 3’, 101° 50’ |1°392; 113,752 847
BG It eae ea 121° 26'| 99° 29" |1°346 111,824 * 862
1:14 118° 00'| 97° 11/|1°300| 109,896 | -877
1-12 114° 44’| 94° 56’ |1°254| 107,968 °893
ALO 111° 36’. 92° 43’ }1°210| 106,040 *909
1-08 108° 36’. 90° 33’ |1°166| 104,112 *926
1:06 105° 42’) 88° 26’ | 1-124 102,184 *943
1°04 102° 53’|. 86° 21’ | 1-082 100,256 "962
1:02 a 100° 10’; 84° 18’ | 1-040 98,328 “980
1-00 180° 0’ | 97° 81’|. 82° 17' | 1-000 96,400 | 1:000
0°98 T57°. 2K] 94° 56") 80°17! | =960| 94,472 1:020
0:96 147° 29’ | 92° 24’). 78° 20’) °922) 92,044 1°042
0:94 140°. 6’ |» 89° 56'|.. 76° 24’ | +884 90,616 1:064
0-92 138° 51" |} 87°: 32'| 74° 30’) +846 88,688 1:°087
0:90 128° 19’ | 85°. 10’) 72° 36’ | +810 86,760 1-111
0:88 123° V7" |. 82° 51. 70° 440 1 774 84,832 1°136
0:86 118° 38’ | S0° 34’| 68° 54’ | »740 82,904 1/163
0:84 1949319). 7 80° 2017. 672. 654-7106 80,976 1:190
0:82 110° 10’.| 76° 8'| 65° 18’ | +672 79,048 1°220
0-80 106° 16’ | 73° 58’| 63° 31’ | 640 77,120 1°250
0:78 102° 31’ | 71° 49’; 61° 45’ | -608 75,192 1-282
0:76 98° 56’ | 69° 42’| 60° 0’ | +578 73,264 1 316
0°74 95° 28’ | 67° 36’) 58° 16’ | -548 71,336 1:351
- 0°72 92°. -6’ | 65° 32’). 562 32' | *518 69,408 1-389
0°70 88° 51’ | 63° 31’; 54°50’ |. 490 67,480 1-429"
0°68 — 85° 41’ | 61° 30’, 53° 9! | +462) 65,552 1°471
0°66 82° 36’ | 59° 30’, 51° 28 | -436, 63,624 1°515
0-64 979° 35! | 579.31" 49° 48’ |} :410; 61,696 1°562_
- 0°62 760 38’ | 55° 34’| 48° 9° | +384! 59,768 | 1°613.
0:60. 73° 44’ | 58° 38’| 46° 30’ 360 57,840 1°667
0:58 70° 54’ | 51° 42’) 44° 51’ 336 55,912 1°724
0°56 "68°. 6’ |. 49° 481). 43° 14° 314 53,984 1°786
0°54 65° 22" |°47° 54") 419 37! 292 52,056 | 1°852
0-52 62° 40’ | 46° 2’) 40° 0’ 270 50,128 1:923
0°50 60° 0’ | 44° 10'| 38° 24’ 250 48,200 | 2-000
‘Exawrie.—The apertures of four objectives, two of which are dry, one water-immersion, and one oil-immersion,
‘would be compared on the angular aperture view as follows:—106° (air), 157° (air), 142° (water), 130° (oil).
‘Their actual apertures are, however, 98 j "80 *98 1+26 1°38 or their
|. numerical apertures.
<1 eas
(
Be)
Conversion of British and Metric Measures,
1.) LInEAu
Micromillimetres, §c., into Inches, §c.
II.
Scale showing ||
the relation of i :
Millimetres, & poe
&c., to Inches. |) 1 -000039
| 2. +000079
‘aud | 8 7000118 |
com.” ins. | 4 -+000157
5 -000197
l= ™ 6 +000236
les 7 -000276 |
=a 8 000315 |
[= | 9 -000354 |
ft 10 *000394 |
E | 11 +000433
Ae 12 -000472
=H 13 -000512 |
[Es 14 -000551 |
Hi 15. -000591
jes 16 -000630
ce a 17 -000669
le z| 18 -000709
=i 19 -000748
E z| 20 +000787
[Es 21 000827
= 5| 22 -000866
ae 28 -000906
= el) 24 -000945
Es 25 -000984
Es 26 -001024
=a 27 -001063 |
Hy] | i ue
=u 001142 |
=5 30 -001181 |
: | 81 -001220
4 32 -001260
[E | 83 *001299
=m 84 -001339
lz | 35 -001378
= 36 "001417 |
|e ® 37 ‘001457 |
Es 39 -001535
= w : :
i F| 40 -001575 |
ita 41 -001614
lz | 42 -001654
== 43 -001693
[= :| 44 -001732.
EE 45 -001772
=n 46 01811
[Ee 47 001850 |
ee 48 -001890
[ze 49 -001929
= BS 60. -001969 |
lz | 60 -002362 |
zs 70 002756 |
= 80 -003150 |
(Ss 90. -003543 |
= fl 100 -008937 |
E z | 200 -007874 |
=# | 800. 011811)
[Es | 400 *015748 |
os | 500 -019685 |
| 600 023622
1000'9 2 =) mms} ZOO | 027559 :|
-.10mm=lem |) 800 +031496 |
. 10cm, =1 dm, 900 _ +0354383
10 dm. =1 metre.) LOOO (=1 mm.)
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ITI. Corresponding Degrees in the
Fahrenheit and Centigrade
Scales.
Fehr. Cent. Cent. Fabr.
500 260° 0 100 212°0
450 232-22 98 208°4
400 204-44 96 204-8
350 176° 67 94 201-2
300 148-89 92 197-6
250 121°11 90 194-0
212 100-0 88 190°4
210 98°89 86 186°8
205 96-11 84 183-2
200 93°33 82 179°6
195 90-56 80 176°0
190 87°78 78 172°4
185 85°0 76 168-8
180 82-22 74 165°2
175 79°44 72 161°6
170 76°67 70 158°0
165 73°89 68 154-4
160 71-11 66 150°8
155 68°33 64 147°2
150 65°56 62 143°6
145 62°78 60 140-0
140 60-0 58 136°4
1385 57°22 56 132-8
130 54-44 54 129-2
125 51:67 52 125°6
120 48°89 50 122-0
115 46-11 48 118°4
110 43°33 46 114°8
105 40°56 44 111-2
100 37°78 42 107°6
95 35°0 40 104 0
90 32-22 ' 38 100-4
85 29-44 36 96°38
80 26°67 34 93-2
75 23°89 32 89-6
70 21°11 30 86:0
65 | 18°33 28 82°
60 15-56 26 78
55 12°78 24 75
50 10-0 22 71
45 7°22 20 68
40 4:44 18 64-
35 1-67 16 60-
32 0-0 14 57°
30 — I-11 12 53°
25 =~ 3-89 10 50°
20 — 6°67 8 46°
15 — 9-44 6 42°
10 — 12-22 4 39°
5 — 15°0 > toe ip Ts
0 —.17°78 8) 32°
— 5 — 20°56} — 2 28°
— 10 — 23:33 | — 4 24°
— 15 — 26°11 | — 6 215
— 20 — 23:89; = 8g eS
— 25 — 31°67 | — 10 14:
— 80 — 34°44 | - 12 10°
— 85 — 37°22 | — 14 6°
-— 40 — 40°0 — 16 3°
— 45 — 42°78 | — 18 — 0
-— 50 — 45°56 — — 4
SHE OROANUDHROANUHKROTRNBDHROANAL
| Diamond
|. Phosphorus
| Pure water
IV. Refractive Indices, Dispersive
Powers, and Polarizing
Angles. Pare |
(1.) Rernacrive xpices.
ae
Bisulphide of carbon
Flint glass
Crown glass
Rock salt
Canada balsam
Linseed oil (sp. gr. -932)
Oil of turpentine (sp. gr. *885)
Alcohol
Sea water
Air (at 0° C. 760 mm.)
' A a big pe . atk iad aby Op
(2.) DIsPERSIVE PowERs,
Diamond
Phosphorus
Bisulphide of carbon
Flint glass
Crown glass
Rock salt
Canada balsam
Linseed oil (sp. gr. *932)
Oil of turpentine (sp. gr. 885)
Alcohol a
Sea water
Pure water bere PAN oe ei c®
Air ee ee
(3.) Potarizinae ANGLES
Diamond
Phosphorus
Bisulphide ef carbon
Flint glass
Crown glass —
Rock salt —
Canada balsam ~ ie
Linseed oil (sp .gr. -932)
V. Table of Magnifying Powers.
( il)
- OBJEC-
Beck's 2,
1 Powell’s 1, and
Ross’s A | Ross’s B,
nearly.*
MAGNIFYING Powrr.
Beck’s 1, | Powell’s 2,
5 | % | 10
Be
Powell's 3.| Ross's C. | Beck’s 3, | Powell’s 4,
Qin. | 25 | lin.
EYE-PIECES.
ck’s 4,
Beck’s 5
Rises E. | Powell's 5.
10 15
123 183
162 25
25 3
33h 50
50 vis)
623 932
652 | 100
215 1123
100 150
125 187}
150 | 225
1662 | 250
200 300
250 | - 375
300 450
350 525
400 600
450 675
500 750
550 825
600 | 900
650 | 975
700 | 1050
750 | 1125
soo | 1200
850 | 1275
900 } 1350
950 | 1425
1000 | 1500
1250 | 1875
1500 | 2250
2000 | 3000
2500 4 3750
-3000 j 4500
4000 | 6000
af “Teepectively yf,
20
25
333
50 -
663
100
125
1332
150
200
250
300
3234
400
500
less and ue more than the figures given in this column.
* - Powell and Seaiurare No, 2= 7-4, and Beck’s No. 2 and Ross’s B= 8 magnifying power, or
Ross’s F,
Ro:-s’s D,
FocaL LENGTH.
Zin. | Sin. | Lin. | fin.) din. | din
Maeniryine Power,
} } ‘
| 1p | 1 20 | 2 20 | 40
AMPLIFICATION OF OBJECTIVES AND EYE-PIECES
- COMBINED.
25 30 40 50 60 80
312 374 50 623 15 100
412 50 662 832 100 1331
623 vb) 100 125 150 200
831i 100 133: | 1662 200 2662
125 150 200 250 300 400
1563} 1873 250 312% 375 500
1662 200 2662 3332 | 400 5332
187} 925 300 375 450 600
250 300 400 500 600 800
312} 375 500° 625 750 1000 ~
375 450 600 750 900 1200
4162 | 500 6662 8332 | 1000 13332
500 600 800 1000 1200 1600
+ 625 750 1000 1250 1500 2000
750 960 1200 1500 1800 2400
875- | 1050 } 1400 } 1750 2100 2800
1000 1200 1600 } 2000 | 2400 3200
1125 1350 1800 2250 2700 3600
1250 | 1560 2600 2500 8000 4000
1375 | 1650 | 2200 | 2750 3300 4400
1500 1800 2400 3000 3600 | 4800
1625 1950 2600 3250 3900 5200
1750 2100 | 2800 } 3500 | 4200 | 3600
1875 2250 | 3000 | 3750 4500 6000
2000 2400 | 3200 | 4000 4800 | 6400
2125 2550 | 3400 } 4250 5100 |- 6800
2250 2700 | 3600 | 4500 | 5400 | 7200
2375 2850 | 3800 4} 4750 5700 | 7600
2500 | 3000 | 4000 | 5000 | 6000 | 8000
- 8125 | 3750 | 5000 | 6250 | 7500 | 10009
3750 4500 } 6000 | 7500 |. 9000 | 12000
5000 | 6000 # 8000 {10000 | 12000 } 16000 |
6250. | 7500 } 10000 | 12500 | 15000 } 20000
7500 | 9000 } 12000 | 15000 | 18000 } 240v0
10000 } 12000 | 16000 ¥e a 32000
( 12)
HENRY CROUCH'S
First-Class Microscopes.
Student’s Microscope.
New Family and School
Microscope.
New Series of Objectives.
New Accessories.
$
i
NEW ILLUSTRATED CATALOGUE, ON RECEIPT OF STAMP, MAILED ABROAD. FREE. a
4 . ary a
HENRY CROUCH, 66, Barbican, London, F.C. 4
AGENTS IN AMERICA, iy h . ; a
JAMES W. QUEEN & 00., 924, Chestnut Street, Philadelphia, U.S,
_ VIL.—Note on the Spicules found in the Ambulaeral Tubes o
JOURNAL
OF THE
ROYAL MICROSCOPICAL SOCIETY.
TRANSACTIONS OF THE SOCIETY.
———_—S=
of th
regular Echinoidea. By Professor F. Jerrrey Benn, M.A.,
F.R.MS.
(Read 10h May, 1882.)
Prats V.
I wave thought that it might be of interest to the Society to have
some further information on the feaeece of the spicules found
in the ambulacral tubes of the regular Echmoidea. The greater
part of our present knowledge on this subject we owe to the
researches of one of our Secretaries, Mr. Charles Stewart, the
most important of whose papers was published in the Linnean
Society's ‘Transactions’ for 1865.* I have been emabled to
examine a large series of genera and species, and as my leading
object has been to find some further characters which would be of
assistance in the classification of the groups and genera of the
order, I have confined my attention at present to the sucking-
tubes.
Commencing with the genus Eehinus, I was struck by the
constant presence in iis species of those C-shaped or bihamate
spicules, the characters of which will be known to every microsco-
pist (PL V. Fig. 1). Carrying on these researches further, I
EXPLANATION OF PLATE V.
Fie. 1.—Echinus (E. margaritaceus), to show the ordinary bihamate spicales.
2.— Cottaldia (C. fortesiana).
» o&—FEchinocidaris (£. dufresnis).
4.—FEchinothriz (2. turcarum).
5.— Diadema (D. seiosumi).
6.— Micropuga tuberculaia.
7.— Asthenosoma pellucidum.
8.—Phormosoma bursarium,
9.—Salenia hastigera.
* Vol. xxv. p. 365.
Ser. 2.—Vot. I. xX
298 Transactions of the Society.
found that every genus of the so-called Triplechinide which I
examined contained these same bodies; similarly they were to be
found in the other division (T'emnopleuride) of the Echinide, as
limited by Professor Alexander Agassiz. Nor were they here only ;
when the suckers of the Echinometride were examined, the biha-
mate spicules were again to be observed. In the Cidaride,
Salenide, Echinothuride, Echinocidaride, and Diadematide, the
bihamate spicules were, on the other hand, conspicuous by their
absence ; and this being so, I found in their distribution among
various genera of the Echinometride and Hchinide a gratifying
support to the view on which I have elsewhere insisted, that
these two groups differ less from one another than they do from
any other group of the regular Echinoids. It may be worth while
to give the names of the genera examined :—Heterocentrotus, Colo-
bocentrotus, Echinometra, chinostrephus,* Strongylocentrotus,
Spherechinus,* Pseudoboletia,* Temnopleurus, Salmacis, Mes-
pila, Amblypneustes,* Microcyphus,* Cottaldia,* Echinus, Trip-
neustes, Toxopneustes,* Hvechinus.*
The number of genera examined is now sufficiently large to
justify us in the belief that C-shaped spicules will always be found
in the suckers of the Echinide, as I have proposed to define the
term.
With regard to the form here called Cottaldia, it may be added
that the specimen was collected by the ‘Challenger, and that,
therefore, it was determined by Prof. Alex. Agassiz; a reference to
that naturalist’s report will sufficiently prove that he has had con-
siderable difficulty in finding a place for the species; that difficulty
cannot, however, extend to its general position, now that the
spicules have been examined, and been found to be of the bihamate
type (Fig. 2).
With regard to the Diadematide, we have to note that, if the
forms have been correctly united, there is not the same closeness in
the characters of the ambulacral spicules in this group as there is
in that of the Echinide ; though we can imagine a connection
between the spicules of Echinothria (Fig. 4), and those of Diadema
(Fig. 5) it hardly seems possible to associate with them those of
Micropyga (Fig. 7) or of Astropyga, which have so striking a
Holothurian facies, and no generalization can safely be made at
present for this division.
When Mr. Stewart published his paper in 1865 he had been
unable to find spicules in the ambulacral tubes of Hchinocidaris
(Arbacia). I, too, was for a time unable to find them, but at last
they were detected; they are but scantily present, but are very
characteristic, being greatly widened in the middle, and frequently
t Proc. Zool. Soc. Lond., 1881, p. 418.
* Those marked with an asterisk were not reported on by Mr. Stewart.
Spicules in Ambulacral Tubes of Echinoidea. By Prof. Bell. 299
perforated in that portion (Fig. 3). It would seem likely that the
rarity of these spicules may be ascribed to the great thickness of
the walls of the suckers, the development of muscular and con-
nective tissue being so considerable that there is no such necessity
for the spicules here as there igs in cases where the walls are
thinner ; but the spicules themselves are proportionately large.
The bihamate spicules of the HEchinide, the tri-radiate ones of
Diadema, the flattened centrally enlarged form of Eehinocidaris,
present little in common, and, while there would be no difficulty in
distinguishing them, it is likewise impossible at present to make a
suggestion as to how they might be derived from one another.
When with these we compare the ambulacral spicules of Salenia it
is not perphaps too hardy to suggest that in the irregular forms
there to be found we may have something hardly more than
“amorphous,” from which the forms of the later groups have been
derived.
There is no close resemblance between the spicules of Cidaris *
and those of Phormosoma and Asthenosoma (Figs. 8 and 9); the
reticular character of the spicules of the Echinothuride is doubtless
to be associated with the comparative tenuity of their tests.
* See Stewart, Quart. Journ. Micr. Sci, xi. (1871) pl. iv.
Rew,
500 Transactions of the Society.
VIII.— The Relation of Aperture and Power in the Microscope.*
By Professor Apps, Hon. F.R.MS.
(Read 10th May, 1882.)
I.— General Considerations as to Wide and Narrow Apertures.
Tue question of the relative values of high and low apertures has
been much obscured by the one-sidedness with which it has been
treated. One party of microscopists—the “ wide-aperturists ”—
having recognized that high apertures are capable of exhibiting
minuter details than low apertures, conclude therefrom that all
microscopical work must be done with very wide apertures, and
that low-angled systems are worthless. Another party, relying
upon the fact that there are many cases in which low or moderate
apertures perform decidedly better than wide ones, generalize this
experience and deny that there can be any essential benefit in very
wide apertures, asserting that all observations, with the possible
exception of resolving diatom striz, can be done as well with low-
angled objectives. The premises of both these views may be said
to be true, but true under conditions only ; and by disregarding
these conditions both parties arrive at conclusions which are equally
remote from a proper estimation of the requirements of scientific
work with the Microscope. My view of the question f is based on
the following considerations :—-
1. Every given degree of minuteness of microscopic detail requires
a given aperture in order to obtain a complete (or perfect) image,
i.e. an image which is a true enlarged projection of the structure,
exhibiting all elements in their true form and arrangement. ‘The
minuter the dimensions of the elements the wider an aperture is
necessary—the larger these dimensions the narrower an aperture
is sufficient. Structures whose smallest elements are measured by
considerable multiples of the wave-lengths of light are perfectly
delineated with low or very moderate apertures, and their examina-
tion with wide apertures does not improve their recognition. On
the other hand, if we are dealing with objects whose dimensions (or
structural elements) are equal to a few wave-lengths only, even the
* The paper (received 8th April) is written by Professor Abbe in English.
+ As some suggestion appears to have been made when the above paper
was read as to my views having undergone a change, I beg to remind my readers
that the views above explained are those which I have professed since 1873—the
date of my first paper on the subject. My advocacy of wide apertures for
minute objects appears to have been interpreted as an advocacy of wide apertures
for all purposes—a misapprehension which I am at a loss to account for, as
nothing I have ever said or written could justify any such a supposition.
All the catalogues of Mr. Zeiss issued since 1872 give practical evidence of
this, as the objectives tlere specified (and stated to be constructed according to my
principles and under my direction) include no low and medium powers, except
with low or very moderate apertures.—H, A.
The Relation of Aperture and Power. By Prof. E. Abbe. 301
widest apertures hitherto obtained will not afford complete or
strictly true images, but will show these objects more or less
incomplete or modified. ‘his general principle holds good in
regard to objects of every kind, regular or irregular, isolated
particles or composite structures, because the physical conditions of
microscopical delineation are always the same.
The obvious inference from this principle is that the widest
possible apertures must be used for the observation of objects or
structures of very minute dimensions, low and moderate apertures
for relatively large objects.
It may perhaps be said that the objects of microscopical research
do not justify such a distinction of large and minute, since the
works of nature are always elaborated to the minutest details, all
coarse objects beg composed of smaller elements, and these of
still smaller ones, &c. This is quite true in regard to the objects
considered as uatural things, but not as objects of scientific
research. The interest of research is not always directed to the
ultimate elements, but is as often confined to the consideration of
the coarser parts, and in such cases the observer is not only allowed
but sometimes compelled, to disregard everything which is not con-
nected with the scientific aim of his investigation. To observe
every object in nature throughout, from alpha to omega, is the
privilege of dilettante microscopy only, which has no distinct aim.
There are many lines of the most valuable scientific research (e. g.
the greatest part of all morphological investigations) which have
not to deal with very minute things. This kind of work can be
completely done with low or moderate apertures.
‘Lo recommend the application of wide-angled objectives for
every branch of microscopy, as has been, in fact, done by excited
wide-aperturists, is no more to be supported than it would be to
recommend the use of a magnifier to a painter for inspecting the
tree which he proposes to delineate.
According to what has just been said, the only benefit of
greater aperture is that it is capable of delineating minuter things.
Now minute dimensions require high amplifications in order that
they may be enlarged to a visual angle suticient for distinct vision.
Low figures of amplification cannot render visible (at least not
distinctly visible) details which are beyond a certain limit of
minuteness. Even if they are delineated by the Microscope they
would remain hidden to the eye for want of sufficient visual angle.
It follows theretore that wide apertures will not be utilized unless
at the same time there is a linear amplification of the image, at
least sufficient for exhibiting to the eye the smallest dimensions
which are within the reach of such an aperture. On the other
hand, a high amplification will be useless if we have small aper-
tures which delineate details of dimensions only capable of being
302 Transactions of the Society.
distinctly seen in an image of much lower amplification. We have
here an empty amplification, because there is nothing in the image
which requires so much power for distinct recognition. In the
first case (deficiency of power) the large aperture cannot show
more than a smaller one ; in the other case (deficiency of aperture),
the high amplification shows no more than a lower would do.
Consequently :—
Wide apertures when high amplification is required ; low
or moderate apertures when low or moderate amplifications
are sufficient or cannot be overstepped.
2. The utilization of a given aperture depends in principle on
the amplification of the ultimate image which is projected by the
entire Microscope to the observer’s eye. Now one and the same
amplification may be obtained in very different ways since it is the
resultant of three distinct elements, (a) focal length of the objective,
(b) focal length of the ocular, and (c) length of the tube. Any
definite number of diameters (say 1000) can be obtained with a low
power objective (say a 1-inch) as well, from a mere dioptrical
point of view, as with a higher power (say 1-inch), by applying a
sufficiently deep eye-piece and a sufficient length of the tube. It
is, however, well known that there isa great difference in the optical
qualities of images which are produced under these different con-
ditions. Forcing a high amplification from a low-power objective
is always connected with a considerable loss of sharpness of defi-
nition of the image, owing to the magnification of the residuary
aberrations, which are inherent even in the most finished construc-
tions. It is, therefore, a well-established practical rule that a certain
amount of amplification requires a certain power of the objective—
higher amplification a higher power (shorter focal length)—in
order to obtain the image under those favourable conditions which
are necessary for their full effectiveness. This considered, the
inference of the foregoing paragraph may be expressed in these
terms :—
Wide apertures with objectives of short focal length; low
and moderate apertures with objectives of low and moderate
ower.
hae detailed discussion of this subject will be found in the
second part of this paper, it will be sufficient here to point out
some notable facts of experience by way of example only.
With objectives of say 1 inch, and } inch, focal length, the lower
and medium eye-pieces in use will yield 40-80 and 80-160 dia-
meters only. In order to obtain 150 and 300 respectively, very
deep oculars (or an extra length of the tube) would be required.
So far now as such objectives are intended for the lower powers
mentioned above, an aperture of about 0°15 (18°) in the case of
the l-inch, and of 0:3 (85°) in the case of the 4-inch, are at all
The Relation of Aperture and Power. By Prof. E. Abbe. 303
events more than sufficient for showing every detail which can
possibly be recognized by the eye under these amplifications, and
therefore wider apertures are useless. In point of fact, no observer
will see anything more or anything better with similar objectives
of say 0:40 (48°) and 0°75 (96°) respectively, than with the
narrower angles indicated above, as long as the low and medium
oculars are in question only. These latter apertures would require
for their full utilization, i.e. for convenient observation of the
minuter details which are within their reach, amplifications of
much more than 150 and 300 diameters. With well-made objectives
of those apertures, such figures may be realized indeed, and details
may be shown by means of deeper eye-pieces, which remain quite
invisible with the lower angled systems; but no microscopist can
deny the inferior quality of the images obtained in this way if
compared to those of equal amplification, which are obtained with
these same apertures when the objectives have double the power
and the oculars the half only. Structures of so simple a com-
position as diatom striz may perhaps be tolerably displayed under
such forced amplifications of low-power objectives, but with objects
of somewhat irregular and complicated structure the deterioration
of the image attendant upon a considerable enlargement of the
residuary spherical and chromatic aberrations by deep eye-pieces,
becomes at once obvious even with the most finished objectives. In
point of fact, no experienced histologist will ever use in ordinary
work even an ocular amplification of the amount necessary for
obtaining 100 diameters from a 1-inch objective or 200 from a
3-inch. He would be unwise if he troubled himself with inferior
images whilst good images of the amplifications required could be
obtained with equal, or even greater, convenience with objectives of
the same apertures but half the focal length.
The above is an example of waste of aperture, or lack of useful
power ; waste of power and lack of aperture are exemplified by every
objective of excessively short focal length, e.g. 4, mch. Such a
lens, even if immersion, cannot be made with an aperture of much
greater numerical value than 1-0, in consequence of the technical
obstacles arising with such very short focal lengths. Now the limit
of an aperture of that amount is entirely exhausted, at all events
with a power of 1000 to 1200 diameters, inasmuch as nothing of
the real attributes of an object can be seen with that aperture under
a higher amplification, which could not be as well recognized under
the lower. A 3,, however, will yield 1500-2000 diameters with
the lowest eye-pieces which are usually employed. The lowest
attainable power is therefore an empty power already, and every
useful amplification available with the aperture in question could be
obtained under favourable conditions and with much less inconye-
nience by an objective of half the power, or even less.
304 Transactions of the Society.
3. The preceding shows that wide apertures can only be
utilized in the observation of minute details, under high amplifica-
tions obtained with objectives of short focal length. Wide aper-
tures are therefore useless when those conditions are not fulfilled,
because in this case the same result could be obtained as well
with low-angled systems. But as abundance prima facie is
no detriment, the foregoing considerations do not enforce any
positive objection to the use of wide apertures for every kind
of work. ‘There are however other points of view from which
it becomes obvious that the application of wider apertures than
can be utilized is not merely superfluous but is a decided disad-
vantage, inasmuch as they prevent the utilization of some really
valuable benefits which are the privilege of low and moderate
apertures.
The first disadvantage results from the reduction of the depth
of vision (or the “penetration” of the Microscope) which is
connected with wide apertures. I have given in another place*
a discussion of the circumstances on which penetration depends,
and the formule which afford an approximate numerical estimation
of the depth of vision in microscopic observation. These theoretical
suggestions show (in accordance with the experience of practical
microscopists) the reduction of penetration with increasing aperture
under one and the same amplification, and especially when the
amplification is not restricted to very small figures. Now there
are many objects of microscopical research which do not require,
and, indeed, do not even admit of high powers, but demand for
effective investigation as much penetration as possible. This is
always the case where the recognition of solid forms is of import-
ance, and therefore a distinct (at least, a tolerably distinct) vision
of different planes at once must be possible, whether the observa-
tion is assisted by stereoscopic devices or not. The greater part
of all morphological work is of such a kind, and in this line of
observation therefore a proper economy of aperture is of equal
importance with economy of power.
Whenever the depth of the object under observation is not
very restricted, and it 1s essential that the depth dimension shall
be within the reach of direct observation, low and moderate powers
cannot be overstepped, and no greater aperture should therefore be
used than is required for the effectiveness of these powers—an
excess in such a case is a real damage. High powers and corre-
spondingly wide apertures are restricted to those observations
which do not require any perceptible depth of vision, i.e. to two
different cases (1) when the objects are quite flat or exceedingly
thin; (2) when preparations of greater depth are sufficiently trans-
parent to admit of an ¢ndirect recognition of their solid structure
* See this Journal, i. (1881) p. 689.
The Relation of Aperture and Power. By Prof. E. Abbe. 305
by means of successive optical sections through successive focus-
sing of different planes. For the latter method of observation the
loss of penetration with increasing power and aperture is no draw-
back, but rather an advantage, because it enhances the distinct
separation of the sectional images at successive foci. A disregard
of these natural restrictions in the use of wide apertures is
obviously the origin of the opinion that aperture per se is antago-
nistic to good definition. It is quite true that there are many
even very delicate objects which are much better seen under a
given amplification with a system of very moderate than with one
of very wide aperture, the former giving a clear view of the
whole structure, the latter showing perhaps some distinct points,
but as a whole veiled in haze. Provided, of course, that we have
well-corrected objectives, the fault here is not on the part of the
lens, but on the side of the object, which requires for proper
recognition a greater range of depth than is reconcilable with a
wide aperture. The theoretical suggestion which has been brought
forward in support of the notion that different parts of the clear
area of an objective produce dissimilar images, and that therefore
the resultant image must show increasing confusion with increasing
aperture, cannot apply to the delineation of a plane object. In a
well-corrected objective the partial pictures received through the
various parts of the aperture-area are-always strictly similar so far
as one plane of the object is concerned. ‘he confusion suggested
is nothing else but confusion of the images of different depths—
lack of penetration, but not lack of “ definition” m any reasonable
sense of that term. Provided the objectives are properly corrected
and the objects are fit for the delineation of an image, undisturbed
by interfermg confused images from other planes, the “ defining
power” of an objective is always greater with greater aperture for
every kind of objects, inasmuch as under all circumstances the wider
aperture admits of the utilization of higher amplifications than
can be obtained without perceptible loss of sharpness (with the
same objects) by lower apertures.
There is therefore no drawback in principle to the use of a
large aperture when the objects are suitable. But the considera-
tions above lead to the conclusion :—
Wide apertures (together with high powers) for those
preparations only which do not require perceptible depth of
vision, t.e. for exceedingly flat or thin objects, and for trans-
parent objects which can be studied by optical sections.
Moderate and low apertures when a wide range of pene-
tration cannot be dispensed with.
4. There is still another point of view, and one of special
practical importance, which shows the positive damage connected
with the use of wnnecessarily wide apertures. The increase of
306 Transactions of the Society.
aperturé is prejudicial to the ease and convenience of microscopical
work in two essential respects.
Istly, It necessitates a progressive reduction of the working
distance of the objective. Owing to the rapid increase of the
anterior aberration with increasing obliquity of the marginal rays
(particularly in the case of dry lenses), perfect correction of a
system cannot be obtained unless the layer of low refraction
between the object and the front lens (i.e. the working distance)
is reduced to a certain fraction of the focal length of the system,
which fraction is necessarily diminished in a rapid proportion as
the aperture becomes greater and greater. Whilst there is no
objection to retaining as working distance 1%, of the focal length
for an aperture of 30°, if the aperture is 60° not more than 53,
can be allowed, and with an aperture of 116° really good correction
is not reconcilable with a working distance exceeding 74 of the
focal length. It is therefore an obvious disadvantage to use
aperture angles of 60° and of 116°, when the power which is
required or available can be obtained with 30° and 60° respec-
tively.
2ndly, Increase of aperture is inseparable from a rapid increase
of sensibility of the objectives for slight deviations from the con-
ditions of perfect correction. The state of correction of an objective
depends on the thickness of the refracting film between the radiant
and the front lens, represented by the cover-glass and that por-
tion of the preparation which is above the actual focus. This is
a variable element independent of the objective itself. In order
to avoid large aberrations which must result from the change of
that element, its variation must either be confined to narrow limits
or must be compensated for by a corresponding change in the
objective. Now there is a great difference in regard to this
requirement between the objectives of low and of wide aperture,
in particular with the dry system. An objective of a few degrees
is almost insensible, it may be focussed to the bottom of a trough
of water without any loss of performance. With 30° differences
in the cover-glasses within the usual limits are still inappreciable,
and an object may be seen at the depth of a drop hanging on the
under surface of a cover-glass. With 60° a deviation of the cover-
glass from its standard thickness by not more than 0°1 mm., or a
corresponding increase of the depth of the preparation above the
actual focus, will introduce perceptible aberrations and a visible loss
of definition if not compensated for. With an aperture exceeding
100° in a dry lens, the same result will arise from a change of
thickness of 0:02 mm. only. To preserve always the best cor-
rection in such a system would necessitate a change of the
correction-collar for almost every change of focus in the inspec-
The Relation of Aperture and Power. By Prof. E. Abbe. 307
tion of successive layers, unless the preparation is exceedingly
thin.*
So far as the necessity of obtaining a certain amount of amplifi-
cation in an efficacious manner requires a certain aperture, the
above-mentioned restrictions and difficulties in the proper manage-
ment of the objectives cannot be avoided. But all restrictions in
regard to the objects, and all the trouble taken in the adjustment
of the objectives, is quite for nothing when the same result can be
obtained with a lower aperture. If for the sake of convenience the
precautions required in the use of wide-angled lenses should be
disregarded in working with the lower powers of wide aperture,
the performance of such lenses is always worse than that of much
narrower apertures under the same amplification. The best wide-
angled system, if not carefully adjusted when in use, is not better
than a bad low-angled lens, for the tolerably sharp image, which
could be still obtained through the central part of the aperture
alone (even under the imperfect state of correction) is disturbed
by the coarse dissipation of light from the ineffective marginal parts
of the aperture.
The amateur who likes the Microscope for his amusement may
not much object to some extra trouble connected with the use of
* The reduction of this sensibility in somewhat large apertures is one of the
great practical advantages of the immersion-method. ‘The extreme increase of
that sensibility which is met with when the aperture of dry lenses approaches
the maximal value of a for air (1 N.A.), is in my opinion a strong objection to
the construction of such lenses with greater apertures than 0°80-0°85. Not only
in this case must the working distance be reduced to an intolerably small
amount in order to obtain proper correction, but the preservation of that correction
in the practical use of the systems is almost impossible, notwithstanding the
correction-collar, whilst at all events the very slight benefit of optical performance
is not worth speaking of in comparison to the large increase obtained with the
immersion-method under so much more favourable conditions.
I need scarcely point out here that the claim of a special insensibility of
certain lenses in regard to differences of the cover-glass (as has been sometimes
made) is, to say the least, either great thoughtlessness or simple self-delusion,
just as are similar claims of special penetration in favour of certain objectives.
The aberrations in question, as well as the dissipation-circles from difference of
focus, originate outside the Microscope, The particular construction of the
objective cannot possibly therefore influence their amount in a cone of rays of
given aperture, and the degree in which both become visible in the ultimate image
of the Microscope must be strictly determined by the same elements which
determine the visibility of any real object of given dimensions at the same plane
of focus. There is no room left, therefore, for special properties of different
constructions.
» It is, however, true that an apparent insensibility, as well as an apparent
depth of focus, is sometimes found, viz. in badly corrected objectives. When a
system has no distinct focus at all, it is quite evident that the dissipation-circles
arising from different thicknesses of the cover-glass, and from the difference of
focus of different levels, may become much greater before the deterioration of the
indistinct image becomes visible. Well-corrected objectives must be sensitive in
both respects in strict accordance with their aperture so far as one and the same
system of construction (dry or immersion) is in question.
308 Transactions of the Society.
wide-angled low-power lenses, which he admires as_ brilliant
specimens of optical art. For those, however, who work with the
Microscope, the economy of labour to which they are obliged will
be expressed by the rule :—
Never use wider apertures than are necessary for the
effectiveness of the power, because excess of aperture is
always waste of time and labour.
5. A few remarks about another point of practical interest.
By those who plead in favour of large apertures 2n all cases, it has
been sometimes suggested as a rational plan for reconciling opposite
demands, to have all objectives constructed with relatively wide
angles, and to reduce them by stops or diaphragms when smaller
angles are desired. The greater penetration and insensibility of
the low apertures may of course be attained thereby: but never-
theless this device is only a makeshift; and the result is inferior to
that obtained by objectives originally arranged for a lower aperture.
It is not merely that the stops cannot increase the working
distance (which will always remain at the point corresponding
to the full aperture of the lens), but that the low-angled lens
which is made out of a good wide-angled one by means of a stop,
is in optical respects a relatively bad objective—not nearly as well
corrected as the same power would be if carefully adjusted for the
lower angle. The reason will be readily understood from the
following consideration.
The best correction of an objective of given aperture depends
on the proper distribution of a certain amount of residuary aberra-
tion, which cannot be eliminated with our present means. ‘The
greater the aperture the more aberration must be intentionally left
at the central part of the system in order to prevent an obnoxious
accumulation in the marginal zone. It is obvious, therefore, that
with an aperture-angle of say 90° the inmost cone of 45° cannot
be so well corrected as it might be if the marginal zone could be
left out of account. ‘The effect is by no means inconsiderable,
particularly in regard to the colour corrections. Owing to the
chromatic difference of the spherical aberration the central portion
of a somewhat wide aperture must always, even in a well-arranged
objective, be perceptibly under-corrected chromatically, and in
using this central part alone (the compensating influence of the
over-corrected marginal zone being done away with), we have the
performance of an inferior lens. In point of fact, no intelligent
optician would ever make an objective of 30° aperture on the
same formula as one of 60°, or one of 60° on the same formula as
another of 100°, though this could be done by merely reducing
the clear diameter of the lenses.
There cannot, therefore, be a reconciliation between the pleasure
of exhibiting mere optical accomplishment and the interests of the
The Relation of Aperture and Power. By Prof. E. Abbe. 309
working microscopist. Bad lenses will certainly not meet the
demand for low and medium powers affording the utmost possible
economy of time and labour in scientific work. This can be done
only by systems in which all advantages attendant upon the lower
apertures are fully realized by constructions specially aiming at
the best which can be obtained under the actual conditions of the
case.
The progressive increase of aperture in the higher powers, for-
merly within the capabilities of the dry system, and at a later period
by the development of the immersion method, is, without any reason-
able doubt, the most important feature of the modern advance of
microscopical optics. It has rendered possible the successful ex-
tension of microscopical research to minuter and minuter objects,
which otherwise would have been impossible by the ineffectiveness
of all increase of amplification beyond certain low figures. The
appreciation of that progress and the recognition of its true basis
has led to a tendency to increase more and more the aperture of
every kind of objectives. The fact has been disregarded that it is
an entirely different thing whether the object is to promote
the performance of the Microscope in the whole at the limits of its
power, or to promote its performance for aims beyond these limits.
The opinion has thus arisen that what is a benefit for one kind of
lenses must also be a benefit for every other kind. Objectives of
low and medium powers (1-inch to }-inch) of 15° to 60° are pro-
claimed at this time by many microscopists as old-fashioned and
worthless things; 45° to 100°, or even 60° to 140°, are wanted
for the same powers. Now as from a purely technical point of
view, if 2s an accomplishment when the delineating power of an
objective cannot be exhausted even with the deepest eye-pieces,
opticians (notwithstanding the total bootlessness of such a super-
abundance) of course take pleasure in making such “superior”
lenses, and the natural consequence is that the lower apertures
required for useful scientific research are likely to be esteemed as
second-rate work, no longer worthy of high technical art.
This opinion is a fatal mistake, and its practical effect, if not
counteracted, will be a decided retrogradation of microscopical
optics. Nobody, of course, can have the least objection to the
construction of lenses of any descripition whatever for the personal
pleasure of this or that microscopist. Strong opposition should,
however, be made against all tendencies of captivating microscopical
optics, in favour of such predilections, at the cost of the general
usefulness of the instrument.
Scientific work with the Microscope will always require not
only high-power objectives of the widest attainable apertures,
but also carefully finished lower powers of small and very
moderate apertures.
310 Transactions of the Society.
IX.—The Bacteria of Davaine’s Septicemia.
By G. F. Dowprswett, M.A., F.R.MS., F.CS., &.
(Read 10th May, 1882.)
THE organisms here shown under the Microscope, and which occur
in the blood of the rabbit. in the form of septicaemia known as
that of Davaine (one of the first who described it, about twenty
years ago), are remarkable, in many respects, from a microscopical
point of view, and possess a general interest from their relation to
the affection in which they occur, and which has been regarded
almost as the type of a specific parasitical disease, from the cireum-
stance that the blood of an animal in these cases is infective in
inconceivably small quantities. The statements of Davaine on this
point, which attracted so much attention, were that the trillionth,*
or the ten-trillionth part of a drop of this blood was infective.
His experiments were repeated by several observers, who con-
firmed his results in different degrees. I have myself found, in
numerous experiments, that in the case of rabbits the blood is
usually infective up to the millionth and the hundred-millionth
part of a drop; sometimes in even smaller quantities, obtained by
successive dilutions.
In such blood I have found that the organisms here described
always occur, but in very variable numbers; in some cases not
more than one or two are to be found in each field of view, in
others they exceed many times the number of the blood-corpuscles ;
they do not appear to increase in any marked manner shortly after
death, as is the case in some other affections. The microphyte itself
is a form of Bacteriwm, in the generic sense of the term, as defined
by Cohn ; its diameter, which varies less than that of any other form
of Schizophyte which I have examined, is just over half a micro-
millimetre (0°509 y), almost exactly 5455 m. The length which,
in different stages of development, is very variable, may be put
down at from 13 to 2, 3, or, in a few cases, 5 times the diameter,
that is, of the single cells, or rods as they are commonly termed ;
two or three of these, but not more, sometimes occur united together,
endwise, forming short chains; but they never, in the blood of an
animal, form either long leptothrix filaments or zoogloea masses.
They frequently appear in the form of a figure of 8, or a dumb-
bell ; this, as is shown in stained preparations—an example of which
may be seen in the field of view under the Microscope—is not due
to a constriction of the cell-wall, indicating incipient fission, but to a
difference in its constituent parts and their refractive power ; the
* A trillion in the French notation is a billion in the English, i.e. a million
squared,
Bacteria of Davaine’s Septicemia. By G. F. Dowdeswell. 311
two ends are the most highly refracting, they take the staining
more deeply than the intermediate portion, which is often with
difficulty perceptible ; the ends thus stained present the appearance
of forming spores, in some cases so distinctly that I am disposed to
think this is really the case, though I have never witnessed their
complete development.
The preparation shown is from the blood of a rabbit of the
third generation of artificial infection, it was made very shortly
after death, and treated by the methods introduced by Weigert and
Koch, which have been described elsewhere, and are now pretty
generally known and adopted. I have not found these Bacteria in
any of the organs or the tissues, excepting the blood and the lymph
of an infected animal, examined immediately after death, not even
in the lungs or the spleen, where, judging from other cases, we
should expect to meet with them; their minute size, however,
and more especially their not readily staining, would render them
very difficult to distinguish in the tissues. In the blood this
Bacterium is evidently motile, sometimes very actively so.
Notwithstanding the interest and attention which this affection
has excited during several years, and the importance of the micro-
phyte in relation to the question of the true nature of the contagium,
it has not, I believe, been figured or at all carefully described by
any one, excepting only by Coze and Feltz, in a work published at
Strasbourg and Paris several years ago; their description is im-
perfect, and does not in any way coincide with my own observa-
tions; they even give the diameter of the organism just three
times as great as I have found it. These measurements I have
checked by the use of the admirable standard stage micrometer
recently constructed by Professor Rogers, of Cambridge, U.S.A.,
one of which I have received, and which is most valuable in
enabling different observers to compare exactly their measurements.
The immense discrepancy, however, between my observations and
those of Coze and Feltz, cannot be reconciled by any variations in
the standard scale used, and renders it difficult to believe that the
same organism has been observed in the two cases. This opens up
a very important, indeed a fundamental question with reference to
the etiology of this affection, which need not be discussed here; I
will only say that in the course of very numerous experiments, in
different series, I have found the organism specifically distinct,
invariable and constant in all cases, thereby conforming to the
first and most important condition which has been laid down as a
test for a specific parasitical contagium.
In relation to the dimensions of the organism, and the infective
virulence of the blood in which they are contained, a very curious
question arises as to how many Bacteria or their germs can be
contained in-a given quantity of blood, and this, as far as I know,
312 Transactions of the Society.
has never been yet considered or referred to. Taking the dimen-
sions of the Bacteria to be, diameter 0°5 yw, which is a fraction less
than the actual measurement, and the length to be 2 diameters,
which is undoubtedly under the average, a very simple calculation
shows that in a drop, taken as the 16th part of a cubic centimetre,
there would be 250,000,000,000 (two hundred and fifty thousand
million), or just a quarter of a billion; this would be when the
blood was entirely filled with, or rather replaced by a solid mass of
Bacteria, leaving no space at all for the blood-corpuscles and but
little for the plasma; and this is the utmost number which a drop
cculd contain. I think it is evident, therefore, that there is some
fundamental error in Davaine’s statement and in that of those who
have followed him, on this point. I have endeavoured directly to
enumerate the number of Bacteria present in different portions of
blood, but I cannot pretend to have succeeded with even approxi-
mate accuracy ; the greatest number I could enumerate or estimate
was a few millions in a drop.
Another point of special interest in this affection is the asserted
increase in the infective virulence of septiczemic blood in successive
generations of transmitted infection. This theory was explicitly
maintained by Coze and Feltz, but Davaine’s statements on the
subject have been somewhat misunderstood, for although he asserted
this in the fullest extent at first, he ultimately qualified the state-
ment in some measure by showing that the maximum of viru-
lence is reached very early; subsequent observers overlooked this
qualification, and repeated and even improved upon Davaine’s
original statements. This question has again lately attracted
attention in connection with the relation of micro-organisms to
disease, and the sensational and, were they to be credited, appalling
statements that have been made, and even supported, by high
authority, asserting a transformation of physiological species in
some of the lower organisms, which hypothesis, it was supposed,
might be connected with or account for an increase in infective
virulence in the organisms present in septiceemic blood in successive
generations. On this point I shall only say that I have found in
a long series of experiments recently made, that although the
infectivity of such blood may be slightly variable, there is no such
thing as progressive increase of virulence in successive generations ;
the blood of the first generation is actively infective in the millionth
or the 100-millionth of a drop, or less, and it is not, and indeed
for the reasons already stated, cannot be infective in very much
smaller quantities, in the 25th nor any succeeding generations,
nor is there any shortening of the incubation period, which in the
large majority of cases is remarkably constant, ranging from
twenty-one to twenty-four hours.
The relation of the organisms here described to the disease in
The Bacteria of Septicemia. By G. F. Dowdeswell. 313
which they occur, has recently been the subject of experiment in
Germany ; I shall only say with regard to this that on investi-
gating this question, it appears to me clear that the Bacterium
does constitute the specific virus, the actual contagium of the
affection.
The importance of the relations of these microphytes to disease,
and indeed their role in the whole economy of nature is now so
generally acknowledged that it is unnecessary to dwell upon it.
It is only quite recently that the subject has been systematically
developed, and already most valuable results have been attained,
some of which, in regard to a most important practical application,
viz. to tubercular disease, have only been communicated during the
last month, and demonstrated in this College in the present week.
It is by the microscopical examination of the organisms and the
determination of their specific morphological characters alone, that
many of the most weighty questions which present themselves can
be determined. There is no field of microscopical research which
requires more care or better optical appliances than these organisms,
and none more worthy the attention of microscopists.
Ser. 2.—Vot. II. v
314 SUMMARY OF CURRENT RESEARCHES RELATING TO
SUMMARY
OF CURRENT RESEARCHES RELATING TO
ZOOLOGY AND BOTA
(principally Invertebrata and Cryptogumia),
MICROSCOPY, &c.,
INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS*
ZOOLOGY.
A. GENERAL, including Embryology and Histology
of the Vertebrata.
Germinal Layers of the Chick.j—Professor F. M. Balfour and
Mr. F. Deighton record the results of a renewed study of two much
disputed points in the ontogeny of birds, viz. the origin of the
mesoblast and the origin of the notochord.
1. With reference to the first of these, their results are briefly as
follows :—
The first part of the mesoblast to be formed is that which
arises in connection with the primitive streak. This part is in the
main formed by a proliferation from an axial strip of the epiblast
along the line of the primitive streak, but in part from a simul-
taneous differentiation of hypoblast cells also along the axial line of
the primitive streak. The two parts of the mesoblast so formed
become subsequently undistinguishable. The second part of the
mesoblast so formed is that which gives rise to the lateral plates
of mesoblast of the head and trunk of the embryo. This part
appears as two plates—one on each side of the middle line—which
arise by direct differentiation from the hypoblast in front of the
primitive streak. They are continuous behind with the lateral wings
of mesoblast which grow out from the primitive streak, and on their
inner side are also at first continuous with the cells which form the
notochord.
In addition to the parts of mesoblast, formed as just described,
the mesoblast of the vascular area is in a large measure developed
by a direct formation of cells round the nuclei of the germinal
wall.
The mesoblast formed in connection with the primitive streak
* The Society are not to be considered responsible for the views of the
authors of the papers referred to, nor for the manner in which those views
may be expressed, the main object of this part of the Journal being to present a
summary of the papers as actually published, so as to provide the Fellows with
a guide to the additions made from time to time to the Library. Objections and
corrections should therefore, for the most part, be addressed to the authors.
(The Society are not intended to be denoted by the editorial ‘‘ we.”
t+ Quart. Journ. Mier, Sci., xxii, (1882) pp. 176-88 (3 pls.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. wED
gives rise in part to the mesoblast of the allantois, and ventral part
of the tail of the embryo, and in part to the vascular structures
found in the area pellucida.
With reference to the formation of the mesoblast of the primitive
streak, the authors’ conclusions are practically in harmony with
those of Koller; except that Koller is inclined to minimize the share
taken by the hypoblast in the formation of the mesoblast of the
primitive streak.
Gerlach, with reference to the formation of this part of the meso-
iast, adopts the now generally accepted view of Kdlliker, according
to which the whole of the mesoblast of the primitive streak is
derived from the epiblast.
As to the derivation of the lateral plates of mesoblast of the
trunk from the hypoblast of the anterior part of the primitive streak,
the authors’ general result is in complete harmony with Gerlach’s
results, although in their accounts of the details of the process they
differ in some not unimportant particulars.
2. As to the origin of the notochord, their main result is that
this structure is formed as an actual thickening of the primitive
hypoblast of the anterior part of the area pellucida. It unites
posteriorly with a forward growth of the axial tissue of the primitive
streak, while it is laterally continuous at first, both with the meso-
blast of the lateral plates and with the hypoblast. Ata later period
its connection with the mesoblast is severed, while the hypoblast
becomes differentiated as a continuous layer below it.
As to the hypoblastic origin of the notochord, they are again in
complete accord with Gerlach, but differ from him in admitting that
the notochord is continuous posteriorly with the axial tissue of the
primitive streak, and also at first continuous with the lateral plates
of mesoblast.
The authors add :— The account we have given of the forma-
tion of the mesoblast may appear to the reader somewhat fantastic,
and on that account not very credible. We believe, however, that if
the view which has been elsewhere urged by one of us, that the
primitive streak is the homologue of the blastopore of the lower ver-
tebrates, is accepted, the features we have described receive an
adequate explanation.
“The growth outwards of part of the mesoblast from the axial
line of the primitive streak is a repetition of the well-known growth
from the lips of the blastopore. It might have been anticipated that
all the layers would fuse along the line of the primitive streak, and
that the hypoblast as well as part of the mesoblast would grow out
from it. There is, however, clearly a precocious formation of the
hypoblast ; but the formation of the mesoblast of the primitive streak,
partly from the epiblast and partly from the hypoblast, is satisfactorily
explained by regarding the whole structure as the blastopore. The
two parts of the mesoblast subsequently become indistinguishable,
and their difference in origin is, on the above view, to be regarded
as simply due to a difference of position, and not as having a deeper
significance.
yx 2
316 SUMMARY OF CURRENT RESEARCHES RELATING TO
“The differentiation of the later plates of mesoblast of the trunk
directly from the hypoblast is again a fundamental feature of verte-
brate embryology, occurring in all types from Amphioxus upwards,
the meaning of which has been fully dealt with in the ‘ Treatise on
Comparative Embryology’ by one of us. Lastly, the formation of
the notochord from the hypoblast is the typical vertebrate mode of
formation of this organ, while the fusion of the layers at the front
end of the primitive streak is the universal fusion of the layers at
the dorsal lip of the blastopore, which is so well known in the lower
vertebrate types.”
Development of Lepidosteus.*—Prof. F. M. Balfour and Mr. W.N.
Parker state that the ovum is invested by a thick inner membrane,
and an outer layer of pyriform bodies, which would seem to be metamor-
phosed follicular epithelial cells; the segmentation is complete, though
very unequal; here, as in the division of the epiblast into an epidermic
and a nervous stratum, and in the formation of the walls of the
brain, &c., from a solid “ medullary keel,’ we have resemblance to the
Teleostei; the same is true of the archinephric duct, which is developed
from a hollow ridge of the somatic mesoblast, and, by constriction,
gives rise to a duct with an anterior pore, leading into the body-cavity.
The olfactory sacs arise as invaginations of the nervous layer of the
epiblast, the superficial epidermic layer becoming ruptured to allow
of communication with the exterior; the primitive single opening
divides to give rise to the double opening of the adult. The suctorial
disk of the larva is shown to be formed of papillee composed of
elongated epidermic cells, which probably pour out a viscid secretion.
“The pronephric chambers remain in communication with the body-
cavity by two richly ciliated canals; some of the mesonephric tubes
of the larva have peritoneal funnels. No traces of a hyoid gill were
detected in any larve.
Spermatogenesis in Vertebrates and Annelids.j—A. Sabatier
considers that the observations he has made on spermatogenesis in
Salmacina, one of the Serpulide, throw great light on the process in
Vertebrates.
The spermatospores, or mother-cells, which line the walls of the
spermatic sacs, are, by multiplication of the nuclei and by budding,
covered with claviform pedunculated cells, the protospermoblasts.
Each of these enlarge, detac!i themselves from the group, and in their
turn present a new multiplication of nuclei with superficial budding.
Hence arises a second generation of spermatoblasts, the deutospermo-
blasts, which are ultimately transformed into spermatozoids, the nuclei
of the former forming the heads of the latter, while the body and tail
are filaments of the protoplasm.
This double generation appears to the author to explain, simply
and rationally, the complicated and very extraordinary process attri-
buted by Balbiani to the process of spermatogenesis in vertebrates.
The cellular groups composed of a large round central cell (female
* Proc. Roy. Soc., xxxiii. (1881) pp. 112-9.
t+ Comptes Rendus, xciy. (1882) pp. 172-3.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 317
element), and small peripheral smooth cells applied to their surface
(male element), which he considered to be primordial ovules sur-
rounded with epithelial cells, and consequently as young male
Graafian follicles, are the primitive spermatospore covered with the
protospermoblasts, and the group of daughter-cells, which, according
to Balbiani, are produced by budding of the epithelial cells, are in
fact the deutospermoblasts.
There is therefore no necessity to imagine the intervention of a
conjugation of elements of supposed different sexuality, and a fecunda-
tion of which there is no serious proof.
Further researches on the Plagiostomi (Raja and Scyllium) and
Amphibia (Rana, Hyla, and Bufo), have confirmed the author's views.
He is also satisfied that the oval refracting bodies observed on the sides
of the bundles of spermatozoids before maturity (the “ problematical
bodies” of Semper to which Balbiani attributed a very important
function as the female fecundating element) are simply nuclei of
deutospermoblasts which have not undergone division.
Cell-structure.*—The first portion of W. Flemming’s third con-
tribution to this subject deals with the ovum of the Echinodermata.
He finds that in the ripe ovarian ovum of the Hchinoidea (and it may
be supposed in others also), there is a radiate arrangement of the
protoplasm of the eggs, which persists and even becomes more distinct
during fertilization ; this radiation is not to be confused with the
formation of the asters. There exists a sperm-nucleus which fuses
with the ovarian nucleus ; the sperm-nucleus is formed by the anterior
portion of the head of the spermatozoon, or that part to which
Flemming gives the name of the chromatic substance. The doctrine
of Fol, that the protoplasm of the male element alone enters into
union, cannot be held; what is rather true is that the chromatin (or
nuclear body), both of the male and of the female nucleus, enters into
the formation of thé cleayage-nucleus. The division of this last,
formed, as we have seen, by copulation, differs in no essential respect
from the karyokinetic (indirect) division of other cell-nuclei. All
the filamentar forms, with unimportant changes in certain phases, are
exactly similar to those already noted when describing the division of
the nuclei of the cells of tissue. The mother-star of the karyokinetic
figure has not the same centre as the radial arrangement of the ovarian
protoplasm, The radial forms of the daughter-nuclei have, however,
the same centre; but this is true also of other than ovarian cells.
The author insists on the fact that most ova are very unsuitable
objects for the study of dividing nuclei; the observations by him on
this subject were carried out at Naples on Sphcerechinus brevispinosus,
Echinus miliaris, and Toxopneustes lividus.
Dealing with the phenomena of nucleus-division in the walls of
the embryo-sac of Liliwm and other plants, Flemming directs attention
to the results of Strasburger, from which his own differ considerably.
He finds that in all nuclear figures there are many more chromatic
filaments than that author has represented, and that these do not
> * Aych, Mikr. Anat., xx. (1881) pp. 1-87 (4 pls.).
318 SUMMARY OF CURRENT RESEARCHES RELATING TO
present considerable enlargements or diminutions in size, but that
they are either all of the same thickness, or only here and there
present variations, and these of the very slightest character. There
is no compact plate in the equatorial plane, but only closely packed
coils ; in this plane there is frequently to be observed a clear medulla,
the presence of which appears to have escaped the notice of Stras-
burger. After carrying these criticisms further, attention is drawn
to many points in which there is a resemblance between the cells of
the tissues of animals and plants.
Further studies have been made on karyokinesis and the structure
of the nuclei. As to the latter, we may note that the author finds
that what he has called the “intermediate substance” of the nucleus
contains, after treatment with reagents, and probably also during life,
a fine continuation of the nuclear network. The fine granulation
which may be seen in the intermediate substance of the nucleus with
less powerful lenses, and which was formerly thought to be due to
coagulation in a homogeneous mass, is to be referred to this fine frame-
work; the bars, so to speak, of which it is made up are the direct
continuation of the coarser, and are chromatic. It is, perhaps, to the
presence of these that we have to refer the possibility of colouring
the intermediate substance of the nucleus. The nuclear envelope, so
far as it is capable of being coloured, consists of small peripheral
enlargements of these bars, and is formed of the same substance as
they are. The question whether there is an achromatic membrane
enclosing the nucleus cannot yet be decided.
After giving some account of the polar corpuscles, Flemming
points out that the angles of the filamentar loops, which go to form
the stellate chromatic figure, are often distinctly in contact with one
of the achromatic fibres; the paleness and fineness of the latter are so
extreme that never more than a part of them has ever yet been
detected ; from what he has seen, however, he concludes that this
touching of a chromatic loop with an achromatic filament corresponds
to the natural position. It would follow, therefore, that the angle of
the loop has been attracted by the filament, and that later on the
loops, when the mother-figure divides, would become arranged in two
groups.
In some examples of the star or circlet-forms the chromatic fila-
mentar loops lie so freely that they can be counted, with the aid of
oil-immersion objectives and Abbe’s illuminating apparatus, In the
epithelial cells of the buccal and branchial epithelium of the larve of
salamanders four-and-twenty loops were in three cases quite dis-
tinctly made out. In other cases from 17 to 22 were less distinctly
seen, and the possibility is that in these cases there were really 24
filaments also.
Dealing lastly with some observations on cell-division in Man,
it is stated that in the epithelium of the cornea of an adult subject,
the lowermost layers exhibited rare and scattered cell-divisions, but
here again, just as in Salamandra maculata, the chromatic figures were
detected, but the achromatic could not be seen, so small was the
object. In the blood of a leucocythemic patient cell-division with
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 319
kinetic figures was seen; the blood was excessively rich in colourless
cells, and had a yellowish-white colour; of several thousand cells, it
was computed that only one per thousand exhibited karyokinesis.
From this it may be concluded either that in leucocythemia the
colourless cells multiply by direct constriction of the nucleus, or that
indirect cell-division chiefly occurs in the spleen and osseous medulla,
so that it is only rarely that cells are caught dividing in the blood
itself. Dealing with some deviations from the ordinary mode of cell-
division in sarcoma and carcinoma, the author takes the opportunity
of insisting on the fact that as an ordinary rule, nuclear division is
on the same type in man as in the Amphibia.
Summing up the results at which he has here arrived, Flemming
finds that in different objects—ovarian cells, plant-cells, and human
epithelia—he has again been able to demonstrate that the physical
processes and the corresponding mechanics of kinetic nucleus-division
is, or appears to be, everywhere essentially the same; at any rate,
there is no reasonable ground for doubting this uniformity. He then
passes in detailed review the doctrines of Strasburger, a résumé of
which it is impossible to give here. The author states that he sees as
yet no ground for doubting that the nucleus is a division-organ for
the cell, whether or no it has other functions in addition. This view
is the only one which explains the general presence of the nucleus and
the complicated kinetic processes of division. The phenomena ob-
served in the nucleus may lead us some day to a true physiology of
cell-division, and everything which bears, howsoever slightly, on
this point, appears to be of much more importance than any merely
morphological facts.
In using the term “ homology of the processes,” no reference has
been imagined to phylogenetic considerations, and if serious objection
be taken to its use, we have only to replace it by “ homotypy.” The
questions raised in this connection by Strasburger have no importance
for the histologist.
Theory of Ameboid Movements.*—Mr. J. B. Haycraft endeavours
to account for the throwing out and subsequent retraction of the
pseudopodia (of white blood-corpuscles and unicellular organisms),
“pointing out, it may be, but one factor, but that a probable one.”
The author’s suggestion is that in those corpuscles which exhibit
amceboid movements, they are due to contractions of the stroma or
network of the protoplasm, which contracts at every part except where
the pseudopodium springs from, forcing the interstromal matter at
this point through the aperture left patent.
“This accords well with the fact that the pseudopodia seem
actually to be projected always as radii from the cell, and that they
are of a very hyaline nature. The difficulty is to comprehend the
forces engaged in their retraction. There are probably at least
three :—(1) the relaxation of the stroma; (2) the viscosity of the
substance; and (3) surface tension, in virtue of which a body tends to
assume the spherical shape.
* Proc. Roy. Soc. Edin., xi. (1881) pp. 29-33.
b]
320 SUMMARY OF CURRENT RESEARCHES RELATING TO
Now this may be very well theoretically, but are these three
factors equal to the occasion ? is the question before us. I have imitated
the structure of the Ameba in the following way :—
An indiarubber ball is pierced by two or three holes near together ;
these should be about the diameter of a common darning-needle. A
larger aperture (half an inch across) is then made in the ball, but
opposite to the smaller holes, and the ball half filled with white
of egg (unboiled) tinted with magenta. The ball represents the
stroma, while white of egg takes the place of the interstromal
matter. The ball is now dipped into a beaker of water to which
sugar has been previously added until its specific gravity is equal to
that of white of egg. Place a finger over the aperture through which
the ball was filled, and press upon it with the other fingers of the
same hand. Beautiful little magenta-stained pseudopodia will be
projected from the small apertures into the sugar solution, and on
relaxing the pressure, still keeping the finger over the aperture above,
the pseudopodia will be completely retracted. I have been able in
this way to project them three or four inches, and afterwards they
have been completely retracted.
One might use common water in place of sugar solution, but as
the specific gravity of the white of egg is greater than that of the
water, the pseudopodia, when they have been projected more than an
inch or so, break off and fall to the bottom. ‘The size of the aperture
is also rather a nice point, for there is one size—roughly ,; inch in
diameter—which is best suited for white of egg, although any sized
aperture will answer, though not so well. This no doubt varies with
the fluid used; ordinary ink may be substituted for white of egg, and
oil for the sugar solution.”
The author cannot but believe that in the stroma the active cause
for these movements is to be sought for, and, as faras he can see,
the mode described above for its action is least in antagonism to
known facts.
While, no doubt, many of the bulgings seen in the white corpuscle
of the newt’s blood are due to changes in shape of the whole cell,
probably with slight local accumulation of interstromal matter, yet
may it not be that many of those fine hyaline processes are but inter-
stromal matter projected from the cell ?
Distinctions between Organisms and Minerals.*—In 1878 G.
Fournier, by mixing together certain inorganic salts, produced pseudo-
organisms, which in form and structure might easily have been con-
founded with cryptogamic plants, and similar experiments have now
been made by D. Monnier and C. Vogt, who describe them as
follows :—
Figured elements presenting all the -characteristics of form
belonging to organic elements, such as cells, simple and with
porous canals, tubes with sides, with septa, and with heterogeneous
granular contents, may be produced artificially in an appropriate
liquid by the joint action of two salts forming by double decom-
* Comptes Rendus, xciv. (1882) pp. 45-6.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 321
position one insoluble salt or two such. The one of these salts must
be dissolved in the liquid, whilst the other must be present in a solid
form.
These forms of organic elements (cells, tubes, &c.), being produced
either in a liquid of organic or semi-organic origin (such as the
saccharate of lime), or an absolutely inorganic liquid (e. g. silicate of
soda), there can be no longer any question of distinctive forms cha-
racterizing inorganic bodies on the one hand and organic on the
other.
The formation of such pseudo-organic figured elements depends
on the nature, the degree of viscosity, and the concentration of the
liquids in which they are produced. Certain viscid liquids, such as
solutions of gum arabic, or of zinc chloride, yield nothing of the kind.
The forms of these pseudo-organic products are constant with
reference to the salt employed, and constant also as any crystalline
form of minerals. This characteristic form is so well maintained
that it may even serve for the detection in mixtures of a very minute
proportion of a substance. This form may be employed as a means of
analysis, as sensitive as spectral analysis, and to distinguish for
instance the alkaline carbonates, sesqui-carbonates, and bi-carbonates
from one another.
The form of the artificial pseudo-organic elements depends prin-
cipally on the acid which enters into the composition of the solid salt,
The sulphates and the phosphates in certain cases produce tubes,
whilst the carbonates give rise to cells.
With some exceptions, such as copper, cadmium, zinc, and nickel
sulphates, the pseudo-organic forms are only produced by means of
substances which are found in real organisms. Thus the saccharate
of lime produces organic forms, whilst those of strontia and baryta do
not.
The artificial pseudo-organic elements are enveloped in true mem-
branes possessing a high degree of dialysing power, and giving
passage only to liquids. They have heterogeneous contents, and
produce in their interior granulations arranged in a reeular order.
They are, therefore, both in form and constitution, absolutely similar
to the figured elements of which organisms are constructed.
It is probable that the inorganic elements contained in organic
protoplasm play a certain part in the constitution of the figured
organic elements for the determination of the forms which those
elements present.
It is suggested * that by these experiments one of the characters
by which mere lifeless matter was till yesterday differentiated from
the living organism is wiped out. There are no longer any distinc-
tive forms by which we may distinguish the two great classes, and it
is asked whether it is not very possible that such structures might be
produced without human intention and interference, in what may be
called an accidental manner? Might they not, considering the large
proportion of silica which they contain, become preserved for ages,
and continue to display pseudo-organic features ? Suppose we find, in
* Journ. of Sci., iv. (1882) pp. 148-53.
322 SUMMARY OF CURRENT RESEARCHES RELATING TO
a rock, certain structures exhibiting apparently organic cells, are they
the remains of true organisms or of pseudo-organisms? ‘This con-
sideration, at least till it has been further studied, is not without its
bearing upon such questions as the organic or mineral nature of the
structures found in meteorites, and, e. g., of Hozoon canadense.
B. INVERTEBRATA.
“Symbiosis of Animals with Plants ’’—Chlorophyll-corpuscles
and Amyloid Deposits of Spongilla and Hydra.*—Professor E. R.
Lankester discusses this subject in an interesting article, with special
reference to the recent views of K. Brandt t (endorsing those of
Semper) that the green-coloured corpuscles found in the cells of
Spongilla fluviatilis and Hydra viridis are not similar in nature to
the chlorophyll-bodies of plants, but are parasitic or ‘symbiotic ”
unicellular alge.
Whilst Professor Lankester considers that there is “ very nearly
sufficient ground” for accepting the existence of “ symbiosis” so far
as regards the “ yellow cells” of Anthozoa and Radiolarians, yet he
regards Semper and Brandt's extension of it to Spongilla and Hydra
as not justified. It appears to him that the green-coloured corpuscles
found in the latter case are clearly similar in nature to the chloro-
phyll-bodies of green plants, and that “there is no more reason to
regard them as symbiotic alge than there is to regard the green
corpuscles in the leaf of a buttercup as such.”
In the course of the discussion it is pointed out that the investi-
gation of the claims of any given greenish-coloured pigment to be
regarded as “chlorophyll” is by no means a simple matter. Sup-
posing the pigment to be soluble in alcohol, we still have to ascertain
which of Sorby’s three groups (chlorophylls, xanthophylls, lichno-
xanthines), are present, and which of each of the species distinguished
by him within those groups.
In order to do this we have to rely on :—
Ist. Variations in degree of solubility in such media as alcohol,
ether, benzine, carbon bisulphide.
2nd. Absorption spectra of the series of solutions obtained.
3rd. Fluorescence and spectrum of the fluorescent light of such
solutions.
4th. Reactions of the solutions with acids, alkalies, and oxidizing
and reducing agents, which give rise to new compounds or change
the spectra characteristically.
There are, however, two other categories of phenomena in relation
to the chlorophyll-bodies of green plants which comprise data of a
nature to assist us in judging of the similarity or dissimilarity of the
green pigments of animals compared with that of the chlorophyll-
bodies. There are, 5thly, the physiological activities associated with
the chlorophyll-bodies of plants; and 6thly, the morphological features
of these bodies. ;
* Quart. Journ. Micr. Sci., xxii. (1882) pp. 229-54 (1 pl.).
+ See this Journal, ante, p. 241.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 323
If we find in an organism physiological processes associated with
the presence of a green pigment, which processes are identical with
those associated with the presence of the green pigment occurring in
the chlorophyll-bodies of plants, we have so far a certain amount of
evidence in favour of the identity of the green pigment in the two
cases. And again, if we find that the green pigment in an organism
occurs in corpuscles which are morphologically similar to the chloro-
phyll-bodies of plants, we have so far evidence in favour of the identity
of the green pigment in the two cases.
In the author’s view there is only one animal—Spongilla fluviatilis
—in which the presence of chlorophyll has been definitely established
by chemical and spectroscopical investigation (Dr. Sorby). The full
corroboration by physiological and morphological evidence is still
wanting, although to Mr. Geddes’ physiological researches on Con-
voluta Schulz “ some value must be ascribed.” Similar physiological
evidence in favour of the assimilation of the green pigment of Hydra
viridis to that of green plants has also been obtained by Mr. J. E.
Blomfield.
A full statement is given of the author’s own observations with
reference to the form under which the green pigment of Spongilla
occurs, which confirm the spectroscopic evidence, and refute the view
of Dr. Brandt that chlorophyll is never formed by animal organisms,
but, when found in animal cells, is due to the presence of parasitic
alge. No cell-nucleus really exists in connection with the green
corpuscles of Spongilla or Hydra as asserted by Brandt, nor does his
important observation of the formation of starch in isolated chloro-
phyll-corpuscles tend in any way to prove that they are independent
organisms but simply that a bit of protoplasm with its associated
envelope or cap of green substance can retain its vital activity just as
a piece of Ameba can. From Brandt’s account of his experiments in
infecting Infusoria with the supposed parasites of Spongilla and
Hydra,it is at once apparent that they are opposed to and not in
favour of the parasitic theory. The chlorophyll-corpuscles of Spon-
gilla were digested or else ejected by the infected Infusoria. In other
eases the chlorophyll-corpuscles of Hydra remained in the Infusorian’s
body unchanged. Had Brandt’s view been confirmed, the green
corpuscle ought to have multiplied in its new host, and even such
evidence of a temporary manifestation of vitality after removal from
the Hydra or Spongilla would not be at all conclusive to the effect
that the chlorophyll-corpuscles are independent organisms, and not
parts of the protoplasm of the cell in which they are normally
found.
With regard to Hydra, a very strong argument against the sup-
posed parasitism is found in the fact noticed by Kleinenberg that
minute angular fragments of a given colour are often present together
with the normal corpuscles. These present no difficulty if the
corpuscles are regarded as products of the animal’s cell-protoplasm,
but are inexplicable on the parasite theory.
The final conclusion is that a careful study of the chlorophyll-
corpuscles of Spongilla and Hydra reveals their correspondence with
324 SUMMARY OF CURRENT RESEARCHES RELATING TO
the known structure of the chlorophyll-bodies of plants; and those
who, like Semper and Brandt, have supposed them to be parasites,
have been misled, first by an imperfect acquaintance with the character
of chlorophyll-bodies in general and of these in particular, and
secondly by the plausible but delusive analogy presented by the
“ yellow-cells ” of Radiolarians and of Anthozoa.
There is a field for experimental inquiry in regard to animal
chlorophyll, as it is very important to know whether it serves the
same purpose as in the plant, and if so, whether we may not be able
to get indications as to the disputed function of the green pigment
which plants are unable to furnish.
Paleontological Significance of the Tracks of Different In-
vertebrates—Herr Nathorst has instituted some very interesting
and important experiments in explanation of the traces in rock
formations of various organisms. As we have not the original, we
give the following report on it by T. Fuchs : * —“ In the sandstone
and marl of all formations there are often found, in greater or less
quantities, certain marks and imprints the nature of which has been
hitherto problematical, as they have been interpreted either as alge
or animals, or simply regarded as inexplicable. Such are the Fucoides
Harlani from the Cambrian of America, the Nemertites of the culm-
shales, the ‘ Zopfplatten’ (a term applied to flattened hair-like
impressions) of the Jura, the endless varieties of different ‘ hiero-
glyphs’ of the Flysch formation, as well as the various impressions
described as Prolichnites, Hophyton, Spirophyton, Taonurus, &e.
Nathorst has hit upon the happy idea of solving this problem by
allowing different animals to crawl or run over soft mud, and then
studying the tracks thus made by them. Although he has only
experimented with about 40 marine animals, and a few insects, larvee,
and earth-worms, still the result of his researches was truly astonish-
ing, as he succeeded not only in artificially representing the finest
Nemertites, Harlanie, ‘ Zopfplatten, Hophyton, &c., but he made the
most unexpected discovery, that by far the greater number of the
so-called ‘ Fucoids’ (e.g. Buthotrephis, Chondrites bollensis, Ch.
hechingensis, and even the Fucoids of the Flysch, are nothing else
than branched worm-tubes. However unexpected this discovery may
be, there can hardly exist a doubt as to its accuracy after the experi-
ments and evidence of the author. On taking several worms of the
species Goniada and Glycerea, which are found in great numbers on
the coasts of Norway, and allowing them to crawl over soft mud, he
observed, to his astonishment, that they invariably made a branched
track, like the twigs of a tree. They first advance a short distance,
then go back a little over the track, and turn away on one side, thus
producing a branch; this they repeat from different points and on
different sides, finally returning to the point whence they started,
and make a second main track in another direction, which they
* HWandl. K. Svenska Vetens. Akad., xviii. (1881). Verh. k. k. Geol.
Reichsanst., 1881, p. 346. See Naturforscher, xv. (1882) pp. 113-16.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. D2)
branch in the same manner as before. In this way a whole tree is
produced.
This manceuyre is carried out by the worms, not merely on the
surface, but they also burrow into the mud and from a given point
produce a system of branched tubes, which being lined with a slimy
coating, acquire a certain firmness. If a thin mixture of plaster of
Paris be carefully poured over this perforated mud or clay, it will
enter the tubes, and by carefully washing off the mud after the plaster
is fixed, the cast of the tubes will bear the appearance of a delicate
tree.
If it is assumed that a bed of mud or clay can be thus burrowed
by Goniada and Glycerea, and that the burrows can be filled with a
soft substance, there will consequently be seen in a section of this
bed, branched impressions which have the appearance of Alge, but
which are, in reality, branched tubes made by worms.
With regard to the fossil Chondrites, especially Chondrites bollensis
and hechingensis, and the Chondrites of the Flysch, it had already
occurred to many that these so-called Fucoids did not lie, like other
fossil plants, pressed flat between the strata, but that they were found
much more nearly in their proper form in the beds of marl, as though
they had grown through them. It was also remarkable that they
were never found in a carbonaceous condition, but invariably in marl.
Heer has also drawn attention to the fact that these ‘ Fucoids’ occur
in all formations, from the las to the upper eocene, in almost
identical forms, while in existing seas hardly any analogous specimens
can be found. This fact was the more inexplicable when it was con-
sidered that, for example, the alge of the Paris limestone, or the
Flysch of Monte Bolea bore the closest resemblance to the existing
forms of alge, so that at the period of the eocene formation, types
of algze existed analogous with the present.
There were also other difficulties. Algze always grow only in
small depths on a firm foundation, and never in mud. Now the
localities in which the so-called Fucoids are found in the greatest
quantities are manifestly formations of mud, and deposited in a deep
sea..*
All these difficulties at once vanish when it is known that these
so-called ‘ Fucoids’ of the Flysch are not alge, but only the tracks
of worms; the peculiarity of their origin is then no longer incom-
prehensible. Worms are to be found in the sea at a great depth,
and like especially slime and sand ; and it thus becomes evident that
such perishable impressions as those made by worms are more lasting
in the deep sea than in the formations nearer the shore, because they
are not so easily effaced or disturbed.
Among other marks observed by Nathorst, the following may be
mentioned :—Corophium longicorne (a Crustacean) makes an impression
* It might of course be assumed that alge, like Sargassum, torn from the
place where they grew, and driven out to sea, finally sink down into the mud of
the deep sea, but even with such an hypothesis these Algze would always appear
unusual and accidental, while the Chondrites in the Flysch have a constant
characteristic.
326 SUMMARY .OF CURRENT RESEARCHES RELATING TO
which corresponds exactly with the ‘Zopfen’ of the so-called
‘ Zopfplatten’; Idothea baltica forms Prolichnites; a Planarian
makes a flat, ribbon-like track ; Montacuta makes dentated impres-
sions, which closely resemble Graptolithes; an unknown animal
makes a regular, zigzag, serpentine mark ; a piece of an alga drawn
over mud produced a streaked mark which corresponded exactly with
what is described as Hophyton, and which has hitherto been considered
a plant. Similar impressions were made by the tentacles of Meduse.
Drops of water falling upon mud covered with a thin stratum of
water produced remarkable, regular, wheel-shaped figures, which at a
distance recall Meduse. An earthworm made an impression very
similar to what is usually described as Spirophyton, and hitherto con-
sidered an alga. This was produced in the following manner :—In
creeping over the wet mud, the worm suddenly came to a stand; and
while its hinder part remained motionless, the anterior was stretched
out, while it at the same time bent itself so much to the side that
its head was brought close to the other extremity of the body.
After the front part had thus been stretched to its fullest extent, it
was suddenly drawn back again, without, however, altering the
position of the hinder part and the head.
A complete review is also given of the marks of animals found in
the Swedish rocks, and a catalogue of 129. publications in which these
marks are described and illustrated. At the end of the list is a work
by Saporta and Marion, which appeared about the same time as
Nathorst’s, with the title, ‘L’évolution du régne végétale, les Cryp-
togames.’ In this the authors endeavour to explain, according to
the Darwinian theory, the gradual evolution of plants from the earliest
stages, through the series of geological formations to the present day.
Unfortunately” (it is said), “the greater number of fossil remains
regarded in this book as plants are in reality the marks of worms.’*
Nathorst has also published a second interesting paper + on the
origin of particular marks, which Herr Fuchs abstracts as follows :—
“‘ Some time ago peculiar unknown bodies were found in the Cam-
brian strata of Lugnas in Sweden, which were described by Torell
and Linnarson under the names of Spatangopsis costata and Astylo-
spongia radiata. 'These bodies are in the form of 4-5 rayed stars or
4-5 cornered pyramids, which either lie free in the mud, or with
the under surface adhering to the rocks, or form only an impression
onaslab. Between the rays and corners are occasionally to be seen
crescent-shaped projections. When Nathorst was at Oeresund in
1880, it happened that a large number of Aurelie were thrown on
the shore. The animals all lay with the mouth downwards, and
when he took one up he observed that it had sunk in the soft ground
by its own weight, and that its gastrovascular system had made a
star-like impression, showing the most striking resemblance to the
so-called Spatangopsis. He then followed up the matter further,
partly by making impressions of various Meduse, and partly by
filling up their gastrovascular system with plaster, and so obtained a
* A rather too sweeping assertion. —Ep.
{+ Handl, K. Svenska Vetens, Akad., xix. (1882).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 327
east. The preparations thus made corresponded so exactly in every
detail with the problematical bodies from the Cambrian, that no doubt
could exist as to their identity. The stars and pyramids are casts of
the gastrovascular systems of the Meduse, the rays of the stars and
the angles of the pyramids correspond with the arms, and the
crescent-shaped projections occasionally occurring between the angles
are casts of the genital cavities. The impressions on the slabs of rock
are produced by Meduse thrown on the shore, and which, sinking
more or less into the soft ground by their own weight, make a more
or less complete impression of the body-cavity. The bodies lying
free in the clay were probably produced by Meduse which lay on
their backs, their gastrovascular system becoming filled up with sand
or mud. There are some Meduse which do not swim, but sink into
the mud on their backs, and lie still watching for their prey.
The fact that the number of rays in these fossils varies from 4
to 5 is not an objection to their medusoid nature because in the
present day individuals are found with 5, 6 or 9 rays. Certainly
this deviation from the normal number appears more frequently in
the Cambrian Meduse than in the existing species.
The impression of the disk and traces of the tentacles are still
distinctly seen round a four-rayed star on a rock from Lugnas.
Many slabs are covered with thick, spiral, vermicular bodies, which
Nathorst considers to be arms torn from Meduse. Certain thread-
like marks on sandstone were supposed by him to be made by
swimming Meduse that grazed the ground with their tentacles. He
was also of opinion that the so-called Hophytes, which occur in
great quantities in the same strata as the Meduse fossils, were
without doubt produced by creeping Meduse.
The following species of Medusee from Lugnas have been dis-
tinguished by him: (1) Medusites radiatus Linnars. sp.; (2) Medusites
Jfavosus n. sp.; (3) Medusites Lindstromi Linnars. sp.
Hitherto Medusz were only recognized with certainty in the
Solenhofen slate, and the discovery of Nathorst is therefore of
great interest. It is especially interesting also because these
Meduse occur in the deepest strata that have ever produced fossils,
so that they must be reckoned as amongst the oldest animals whose
tracks are known to us.”
Lymph of Invertebrates.*—C. I’. W. Krukenberg obtained 12-14
drops of pure lymph from a medium-sized Hydrophilus piceus; he
finds that the lymph varies remarkably in different individuals, the
colour being different even when the specimens have lived under the
same conditions. The coagulation which is spontaneously formed in
it is, compared with that of the hemolymph of Mollusca and Crustacea,
of a more membranous nature, and not gelatinous; the lymph under-
goes coagulation at a comparatively low temperature. The melanotic
change of colour presents remarkable individual variations, which lead
to the belief that the body which blackens immediately on exposure to
the air is in certain cases preformed in the circulating lymph. The
* Verh. Nat. Med. Ver. Heidelberg, iii. (1881).
328 SUMMARY OF CURRENT RESEARCHES RELATING TO
hemolymph of Planorbis, like that of Vermes, does not coagulate
spontaneously; the coagulation temperature is very different to that
of the hemolymph of the Gastropoda, for while this coagulates at
60° C., a small amount of fiuid can be filtered from the former at
64° C. The coloration of the fluid of Planorbis is solely due to its
hemoglobin, but the intensity of the colour is never so marked as it
is generally in the Mammalia.
Mollusca.
Development of the Cephalopoda.*— Dr. M. Ussow, in describing
the formation of the germinal glands, points out that the unpaired
ovary is aconical sac occupying the lower part of the trunk, and often,
when mature, of considerable size. The ripe ova fall into the ccelom,
and thence by the ciliated epithelium are carried to the oviduct. By
the antiperistaltic movements of these latter, they are conveyed into
the respiratory cavity, and thence by the contraction of the funnel to
the exterior. The Graafian follicles are so arranged that the central
portion of the ovary is occupied with the younger or with the primor-
dial ova. Each follicle has a separate theca, which is well provided
with blood-vessels coming from the genital arteries. The first rudi-
ments of the germinal glands appear during the periods of embryonic
development, the small group of rounded mesodermal cells which
appear in the third developmental period near the narrow end of the
mantle and behind the systemic hearts, being, undoubtedly, converted
into evarian glands or sperm-glands. Further development, and the
formation of the efferent ducts appear to be post-embryonic. During
these changes the mesodermal cells become converted into a number
of racemose Graafian follicles, the walls of which are formed by the
thin theca, and by a uni- or bilaminate membrana granulosa. A pri-
mordial ovum and the formative yolk are nothing more than a differ-'
entiated and greatly developed epithelial cell of the ovary. As the
cell grows the Graafian follicles increase in size; folds then appear
owing to the development of the granulosa-cells, their glandular inner
surface increases, and secretes the nutrient fluids. The chorion is
not formed till the secretion of the yolk is completed, and when it is
formed there appears the micropyle; the chorion is elastic and trans-
parent. Beneath it in the mature egg there is an inconsiderable
quantity of fluid, which coagulates on heating, and within this there
is the formative yolk, formed of a finely granular protoplasm and
investing the less fluid nutrient yolk.
The first developmental period extends from the commencement
of segmentation to the first appearance of the rudiments of the organs;
there appears to be a striking similarity in the phenomena exhibited
by different members of the group. At first all the cleavage-cells
appear at one pole of the egg, the grooves extending from the central
portion of the formative yolk outwards; the nutrient yolk is regarded
by the author, in opposition to Prof. Lankester, as playing a merely
passive part. Cleavage is at first superficial and only gradually
extends to the more deeply lying parts; in Argonauta argo there was
* Arch. de Biol., ii. (1881) pp. 553-635 (2 pls.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 529
an interval of about one or two hours between fertilization and the
appearance of the first two segmentation-spheres ; in the other forms
from 5-8 hours. After describing the process of segmentation in full,
and discussing the results of earlier observers, Dr. Ussow passes to
the next step, in which the blastoderm, &c., are developed. In the
germinal disk it is possible to distinguish (1) the central portion,
(2) the median portion, or area opaca, more or less ring-shaped in
form, and (3) the lower protoplasmic portion, not yet differentiated
into cells and continued as far as the lower pole of the egg. The
central portion is formed by a single layer and consists of small,
polygonal cells derived from the division of the six primary and two
secondary cleavage spheres. In the fresh condition the finely
granular protoplasm and the sharply contoured nuclei are quite
transparent. The cells are almost all of the same size (0°016 mm.),
the peripheral ones being alone somewhat larger. At first flattened,
they gradually become cylindrical; and frequently alter in form by
dividing longitudinally. ‘The cells of the area opaca are longer, un-
equal in size, and polygonal in form; there are only two or three
concentric rows; they owe their origin to the multiplication of those
cleavage-cells which had been separated off by the development of
the equatorial groove. They are dark in appearance, owing to the
consistency of their protoplasm, and the thickness of the layer. The
broadest and lower portion consists at one time of 32 segments, which
are frequently arranged in pairs; as there is not a single large
cleavage-cell, but 2-6 cells at the thickened apex of each segment, the
edge of the germinal disk is irregular and villous owing to the pro-
jecting angles of the cells; between each pair of segments there is a
clear intermediate space, filled up by an extremely thin layer of the
formative yolk; this disappears as the blastodermic cells multiply.
A little later (86th hour) there appear the rounded cells of the
mesoderm ; these arise from the cells of the median portion, which
undergo transverse division ; each of the cells so formed is rounded,
and gradually takes on a cylindrical form. As soon as these cells
appear the process of division begins to affect all the cells of these
parts of the germinal disk, and is effected either transversely or lon-
gitudinally. Three or four successive rows of the larger blastoderm-
cells, forming the median portion, divide longitudinally as soon as
they have divided transversely ; this, of course, increases the breadth
of the median portion, which algo becomes a thicker and therefore a
darker ring; this ring surrounds the unilaminate and still transparent
central portion. The other six days of the first developmental period
are occupied by the multiplication of the cells of the peripheral
portion of the germinal disk; the upper and median germinal layers
extend over the surface of the nutrient yolk.
At the end of the second day of development the middle layers
consist of several rows of cells; at the same time the ectodermal cells
have continued to undergo transverse division, and have thus narrowed
the central portion of the germinal disk. On the third day, separate
groups of mesodermal cells make their way into the central portion,
and towards the end of that day the upper limits of the mesoderm
Ser. 2.—Vor. II. Z
330 SUMMARY OF CURRENT RESEARCHES RELATING TO
are brought nearer to the superior pole of the egg. The layer which
in all Cephalopods forms the wall of the outer yolk-sac, appears to
the author to be simply formed of mesodermal cells, of which it
would appear to be a direct continuation. The various facts which
Dr. Ussow has observed lead him to think that in the Cephalopoda
the mesoderm is not folded off from the ectoderm, but simply arises
from the transverse division of the cells of that layer. Later, the
diameter of the unilaminate central portion decreases considerably,
while the median zone grows both centrifugally and centripetally.
The cells of the ectoderm at first vary in form and size in different
parts of the embryo; later on they all become short epithelial cells ;
but it is not till the ninth or tenth day that they are to be sharply
distinguished from all the rest, and they are then cylindrical in form.
The mesoderm grows in two directions, towards the central portion
of the germ and the equator of the egg.
Contrary to the opinion of Kélliker and others, the author is con-
vinced that all the Cephalopoda begin to develope from the dorsal
side, and not from the hinder end of their body. Further observations
are promised.
Development of the Oyster.*—Dr. R. Horst points out that the
groove or depression described by Davaine and Lacaze-Duthiers is
the invagination of the embryo, and that the dorsal depression regarded
by Brooks as being the opening of the intestinal tube is really the
shell-gland-invagination. These two inpushings, possessed by the
oyster at one and the same stage, are almost equally well developed ;
later on the ventral side becomes a little pushed out so as to form a
kind of foot. The abdominal cavity is formed by the separation of
the ectoderm from the endoderm. The author confirms the doctrine
of Salensky and Hatschek that the first rudiment of the shell is an
unpaired formation, and he thinks that this is true of all Mollusca;
Carbonate of lime is very early deposited in the shell. The white
spat becomes black spat by the deposition of pigment at different
points in the body of the larva. On the ventral face there is a
button-like thickening of the ectoderm, which is probably the com-
mencing rudiment of the otocyst.
Abortion of Reproductive Organs of Vitrina.j—F. dA. Furtado,
on examining seven specimens of Vitrina from the Azores, found
that there was not the least trace of any reproductive organs, and
Professor L. C. Miall confirms the observation as regards three other
specimens sent to him, Abortion of the reproductive organs has
been observed in animals infested by parasites, e. g. in stylopized bees,
in Lymnea stagnalis when attacked by Trematodes, and in female
hermit-crabs attacked by Rhizocephala. The complete abortion of
the parts, writes Professor Miall in the remarkable case described by
Mr. Furtado, distinguishes it at once from the many cases of real or
supposed functional defect met with in hybrids.
* Zool. Anzeig., v. (1882) pp. 160-2.
t+ Ann. and Mag, Nat. Hist., ix. (1882) pp. 897-9.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 331
Morphology of the Amphineura.*—Dr. A. A. W. Hubrecht gives
a convenient summary of the actual state of our knowledge of this
class of animals, including a brief statement of what is “ known,
surmised, uncertain, or unknown,’ with respect to (a) integument,
(b) nervous system, (¢) intestine, (d) circulatory and respiratory
apparatus, (€) reproductive and excretory organs.
Molluscoida.
New Synascidian.j—Dr. R. Drasche describes Oxycorynia fasci-
cularis, which are found in cylindrical trunks of as much as 6 cm.
in length; the colour of the colony is a dirty green, and the in-
dividuals which are only 10 mm. long have the branchial sac 6 mm.
long. The rounded cloacal orifice is found at the uppermost tip of
the sac. The animals are connected together by a very delicate and
transparent tunic. The nearest ally would seem to be the Chon-
drostachthys of Macdonald,
Alternation of Generations in Doliolum.t—Dr. Carl Grobben
describes this phenomenon in detail, and amongst more general
considerations, points out that nearly all animals which reproduce
themselves by gemmation are of a fixed habit, the matter which is
not used up in the work of locomotion being applied to the pro-
duction and nutrition of buds; gemmation being inconveniently
carried on by a free-swimming form, we must suppose that such free
forms as do multiply thus are derived from ancestors that were fixed ;
we have a good example in the Siphonophora, and the same view
may be applied to the Salpide.
The simplest mode of alternation of generations is, perhaps, to
be seen in some compound Ascidians, where the individuals that
arise from ova are sterile, while those that are developed from buds
develope generative organs. This is a division of labour. In
Pyrosoma the ovum gives rise to a cyathozooid, whence appear
four ascidiozooids, and these multiply either by gemmation or by
the formation of sexual elements. In the true Salpide the nurse
developed from the egg gives rise to a chain of apparently very
different forms which are altogether sexual in their mode of develop-
ment. Here then there is a complete division of labour, and this is
clearly due to their free life. Coming lastly to Doliolum, we find
that here the larva developed from the egg, after losing its tail,
gives rise to lateral and then to median buds, which latter provide
the sexual forms. The differences between the zooids are consider-
able: the nurse has nine, the sexual form has only eight muscular
bands ; the former has an auditory organ which the latter is with-
out; the first nurse of Doliolum has its stolon dorsal, and is there-
fore without a homologue in the rest of the Tunicata ; in other words,
it is a structure which has been independently developed, and in
* Quart. Journ. Mier. Sci., xxii. (1882) pp. 212-28 (11 figs. ).
+ Zool. Anzeig., v. (1882) pp. 162-3.
{ Claus’ Arbeit., iv. (1882) pp. 201-99 (5 pls.).
Z% 2
Sy SUMMARY OF CURRENT RESEARCHES RELATING TO
consequence of its appearance the ventral stolon of other Tunicates
has been arrested in its development, and has become a rudimentary
organ. The appearance of this new, dorsal, stolon is explained by
the inherited capacity of the Doliolida to produce new structures by
gemmation, and its supersession of the ventral one by the following
hypothesis: the dorsal stolon is shown to be more embryonic than
the ventral one by the fact of its only being formed of the three
germinal layers, and not, like the latter, of six rudiments ; we know
that embryonic tissues have a much more considerable growth-energy
than those that are more highly differentiated, and this advantage
became more and more marked by the influence of heredity. The
relations of the different generations is shown in the following
diagrams, where a letter or a combination of letters marks a genera-
tion, A ig a sexual, B an asexual generation, M the median, and L the
lateral buds.
Synascidiz. Pyrosoma. Salpa. Doliolum,
AB AB A A
Vigo * | |
B AB B AB B BA
Le tall / Sey eS | | \=L
AB B AB AB B=As A [A] M
|
A
Dr. Grobben next passes to the phylogenetic history of alterna-
tion of generations in the Acalephz ; in the Hydroids, as Leuckart
has shown, it is due to division of labour, in consequence of which
only some individuals of the colony have produced generative pro-
ducts, and the Medusz have been derived by natural selection from
the free-swimming generative polyps. In the Acalephe the pheno-
menon is likewise due to division of labour among the members of
a colony. After a special reference to the studies of Professor
Semper, the author passes to the Cestodes, where he does not discuss
the question of the phylogenetic development, but merely raises the
question whether we have here to deal with true alternation. He
comes to the conclusion that it is not so, but that we have only a
simple metamorphosis, the larva, vesicle, scolex, and strobila being
one and the same individual in different stages of development. This
is true of the common Tenia, but it does not apply to those cysticer-
coid forms in which several heads are developed, for each head
represents a T'enia-individual with the power of developing proglot-
tids. The history of the Trematoda is dealt with in the same
manner, and it is pointed out that we have here to do not with
alternation of generations, but with heterogony. The author comes
to the conclusion that the so-called spores are ova capable of de-
veloping without fertilization; the generative products are either
single cells (ova), or are derived from the germinal layers of the
mother. In the one case we have sexual, and in the other asexual
development ; or, in other words, unisexual and bisexual generations
appear alternately in the cycle.
Od
Go
Oo
ZOOLOGY AND BOTANY, MICROSCOPY, ETC.
Arthropoda.
a. Insecta.
Nervous System of the Larve of Diptera.*—E. Brandt has
continued his researches on the nervous system of insects.+ In the
larvee of the Leptide, Bibionide, Therevide, Xylophagidew, and
Dolichopodide (families whose nervous system has not hitherto been
examined) there are thirteen ganglia, two cephalic, three thoracic, and
eight abdominal. In the Leptide, the ganglia, instead of being joined
by the simple commissures as in all other Diptera, are united by
double nervous cords, as in the adult. In the next three families the
two first thoracic ganglia are close to one another, while the third is
further off. As the adult has only two thoracic ganglia, the first is
evidently derived from the union of the first two of the larva. In the
Dolichopodide the adult has no abdominal ganglia, and the second
thoracic ganglion is therefore evidently derived from the fusion of the
third of the larva with all the abdominal ganglia.
Several genera and species of families which have already been
partially examined are also described, and the author finds that in
the Tabanide the larve have seven ganglia, and not two only, as
described by J. Kiinckel d’Herculais.
Occident Ants.t—Dr. H. C. M‘Cook publishes in a collected form
his observations on the Honey Ants of the Garden of the Gods,
which we have already dealt with in this Journal,§ and the Occident
Ants of the American plains.
The occident ants build mounds of from less than half a foot to
more than a foot in height, round which they make a circular
“clearing” of grass and other vegetation, presumably by cutting it
away after the manner of the agricultural ants of Texas, previously
described by Dr. M‘Cook. The mound is always covered with
pebbles which have been removed in the process of excavating the
underground chambers and galleries. Some of the pebbles so trans-
ported are ten times the weight of the ant, so that the labour per-
formed would be paralleled by that of a man if he could carry half a
ton up a staircase one-third of a mile high.
The ants do not begin their labour till eight or nine o’clock in the
morning ; so that, as Dr. M‘Cook seems not unwilling to observe,
“it might not be unmeet that those persons whose love of sleep
during late morning hours has been disturbed by the familiar Scripture
proverb, ‘Go to the ant, thou sluggard; consider her ways, and be
wise!’ should return upon their mentors with the above-recorded
facts, and cite this ant, who is indeed no sluggard, as being neverthe-
less fond of a morning nap.” The day’s work, or at any rate the day
of outdoor work, begins by opening the gates which had been closed
* Comptes Rendus, xciv. (1882) pp. 982-5.
+ See this Journal, i. (1881) pp. 234-5.
t M‘Cook, H. C., ‘The Honey Ants of the Garden of the Gods, and the
Occident Ants of the American Plains.’ 8vo, Philadelphia, 1882. Cf. Mr. G.
J. Romanes in ‘ Nature,’ xxv. (1882) pp. 405-7.
§ See this Journal, iii. (1880) pp. 242 and 775.
334 SUMMARY OF CURRENT RESEARCHES RELATING TO
the previous evening. ‘“ The manner of opening the gate cannot be
fully described, because the work is chiefly done within and behind
the outer door of gravel. The mode would doubtless be correctly
indicated by reversing the process of closing gates presently described.
What I saw was, first, the appearance of the quivering pair of an-
tenn above one of the pebbles, followed quickly by the brown head
and feet projected through the interstices or joints of the contingent
grayel-stones. Then forth issues a single worker, who peeps to this
side and that, and after compassing a little cireuit round about the
gate, or perhaps without further ceremony, seizes a pebble, bears it
off, deposits it a few inches from the gate, and returns to repeat the
task ; she is followed sometimes cautiously and at intervals of ten,
twenty, even thirty minutes, by a few other ants, who aid in clearing
away the barricade, after which the general exit occurs. Again
there is a rush of workers almost immediately after the first break,
who usually spread over the hill, bristling around the gate, gradually
widening the circles, and finally push out into the surrounding
herbage. At first the exit hole is the size of a pea, perfectly round,
and plainly shows that sand and soil have been used under the gravel
to seal up the gate. The whole appeared to have been cemented,
probably by the moisture of the night dew.
‘The process of closing the gates is even more interesting to the
observer than the opening, as the various steps are more under his
notice. . . . At nest A the closing was chiefly from within. The
workers pushed the sand from the inside outwards with their heads.
A grass straw about an inch long was brought from the interior and
pushed out until it lay across the gate as a stay for the filling
material. Soil was here principally used for closing, a few pebbles
being added.” In another case, “when the gate was nearly closed a
straggling minor came back from the commons and essayed entrance,
wherein she failed. Several trials and failures succeeded, whereupon
she commenced dragging the dirt from the opening. While thus
engaged the major approached with a huge bit of gravel, which she
deposited on her comrade with as much nonchalance as though she
were one of the adjoining pebbles. At last the minor dug out a
tiny hole through which she squeezed into the nest, and the major,
who was deliberately approaching close behind her, carrying another
pebble, immediately sealed up the opening. During this amusing
episode the straggler made no effort to aid in the closing, being
wholly intent on entering, and the gate-closer paid no attention
to her whatever, beyond the first sudden and satisfactory antennal
challenge. Each moved forward to her own duty with the undisturbed
plasticity of a machine.”
This “ by-play ” between the gate-closers and the late-returning
foragers is not the exception but the rule; nevertheless it does not
appear that the foragers ever so far miscalculate their time as to
arrive after the gates are completely closed. When the gates are all
but closed there is generally but a single ant engaged in the closing
process from without; this ant slips in at the last moment, and the
process is finally concluded from within. The gates are similarly
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. B00
shut during the day-time if the weather seems to threaten a heavy
rain-storm.
The ants, though provided with very formidable stings, are
exceedingly mild and unwarlike. They present the same habits of
“harvesting” as those which were previously known to occur in
allied species of Florida and Texas.
y. Arachnida.
Pycnogonida.*—After a review of what has been done by pre-
ceding naturalists, Dr. P. P. C. Hoek discusses the general form of
the body ; this is strictly bi-lateral, with a proboscis, four segments,
and a rudimentary abdomen. The first segment is formed of one
cephalic and of one thoracic ring; the proboscis ought not to be
regarded as a head, it varies in form, and in length, and in the mode
of its attachment to the cephalothoracic segments. The body may be
slender or robust, the segmentation distinct or obscured ; the abdomen
is represented by a single joint, the length of which varies consider-
ably ; the surface of the body may be smooth or hairy, with or without
tubercles or spines. There are never more than seven pairs of
appendages, and when all are present three belong to the cephalo-
thorax, and are known respectively as mandibles, palpi, and ovigerous
legs; when the first are complete, they have three joints and a
terminal pincer (Pallenopsis); in some cases (Pycnogonum) the
mandibles altogether disappear in the adult state. The palps would
appear to have primitively a number of joints, and this number varies
even within the limits of a genus. There may be ten joints or as
few as three, or the palps may disappear altogether. The females of
all species, however, retain the ovigerous legs, and they are frequently
also represented in the male. The nervous system consists, as usual,
of a cerebrum, an cesophageal collar, and a ventral ganglionic chain ;
in the last there are four or five ganglia, Phowxichilus presenting an
intermediate condition in having the first of its ventral ganglia small
in size, and closely applied to the second; all are distinctly bilobate,
the coalescence of the paired parts being complete. Concrescence
never attains to the extent exhibited in the Brachyurous Crustacea,
for even in Ammeethea it is possible, by the aid of reagents, to discover
the connecting fibres. Nor, indeed, can external form be taken as
giving any true idea of the extent of fusion, for Pycnogonum, in
which there is an extreme condition of external ‘‘ concentration,’ has
the ganglia separated by some considerable distance. After a further
discussion of allied points, the author states the eyes of the Pycno-
gonida have generally a very complex composition; ganglion-cells
and rods can always be made out, but there would not appear to be
any vitreous body; a lens is developed from the integument. The
buccal orifice is triangular, and almost immediately dilates into a very
large pharynx; at its end there is a constriction and a canal is
developed, the length of which depends on that of the cephalic part
of the cephalothoracic segment. ‘The inner face of the cells lining
* Arch, Zool. Expér. et Gén., ix. (1881) pp. 445-542 (8 pls.).
336 SUMMARY OF CURRENT RESEARCHES RELATING TO
this latter are invested ina delicate chitinous layer. The termination
of the cesophagus is not abrupt; its three inner faces are prolonged
towards the interior of the intestine, and give rise to three outgrowths
which have all the appearance of special glands; tubular prolonga-
ticns are, as is well known, connected with the intestine, but, though
they no doubt are very important physiologically, the author has
grave doubts as to their morphological significance.
Great difficulties seem to attend a satisfactory study of the circula-
tory system; the heart has three cavities, at the end of each of
which there is a pair of orifices ; it is probable that there is an aorta,
although it has not yet been detected ; as the author has mentioned
in his ‘Challenger’ report, the dorsal surface of the heart is
remarkable for having no muscular fibres.
The sexes may be easily distinguished, for, with rare exceptions,
the males carry the fecundated ova. Contrary to what generally
happens, the females have lost the primitive organization of the
generative organs, while the males have been more conservative. For
elaborated details on this, as on various other points, the author refers
to his ‘ Challenger’ report.*
Dr. Hoek would place the larve of Pyenogonids with the primary
larve of Prof. Balfour. When we consider the zoological position
and classification of the Pycnogonida, we are led to the conclusion
that the doctrine of Semper, which regards them as Arachnida,
has nothing to defend it; the only real point of resemblance
between them lies in their having the same number of thoracic
appendages; the similarity in the formation of the first pair of
appendages, lately dwelt upon by Balfour, seems to the author to be
of less significance than the fact that this organ is innervated by a
nerve arising from the sub-cesophageal ganglion. Dr. Hoek thinks
that the Pycnogonida must form a distinct class of the Arthropoda,
comparable to the Crustacea, Insecta, &e.
Starting from the protonymph, or larval form common to Asco-
rhynchus, Nymphon, and Pycnogonum, and noting that in the two
former there remain appendages, which become cephalic, while in the
last they are during development obliterated, we have to consider
Pycnogonum as the least ancient form, The doctrine suggested by the
history of the metamorphosis is supported by a study of the nervous
system; in the primitive condition the ventral part of the nervous
system is represented by six ganglia, excluding the more or less rudi-
mentary abdominal ganglia; of the six segments corresponding to
these ganglia, four are thoracic ; and two, in a more primitive con-
dition, belong to the cephalic part. As the mandibles are innervated
by the subcesophageal ganglion, we have three pairs of cephalic
appendages, and this is what is permanently seen in Ascorhynchus and
Nymphon. This possession of three cephalic appendages is, by
various evidence, indicated as the primitive arrangement. Nymphon
retains this most unchanged, but the number of the joints in its
cephalic appendages and the structure of the genital organs forbid us
to regard it as the most ancient form now living. A hypothetical
* See this Journal, i. (1881) p. 886.
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 337
primitive form or Archipycnogonum might be defined as a Pycnogonid
of large size, with strong mandibles of three joints, and armed with a
terminal claw, with long palpi of ten joints, with ovigerous legs of
ten joints, the last four of which are spinous. The thoracic limbs
have eight joints, and end in a claw, with two accessory claws. The
descendants of this form are either delicate and have their limbs
articulated at a considerable distance from one another, or they are
robust and their limbs are set close to one another. Four natural
families may be distinguished—Nymphonide, Ascorhynchida,
Colossendeidz, and Phoxichilide—by the aid of the differences
exhibited in the structure of the appendages.
Spiders’ Webs.*—Mr. R. J. Lecky, referring to the discussion at
the January meeting of the Society (ante, pp. 142-3), writes :—“ The
geometric spider never spins a glutinous web; the entire net is first
made, beginning with the long stays (those alone suitable for optical
purposes), then those at the circumference, next the radial threads,
finishing the net with the spiral ‘ratlins’ (to use a nautical expres-
sion). When these are complete, the spinner begins at the ‘ratlin’
next to the exterior threads, and bedews them at regular intervals with
the glutinous fluid, walking round and round until all is complete.
This fluid spreads, in time, over the ‘ratlins, and so the thread
appears as if spun in a glutinous state at the commencement.”
6. Crustacea.
Limulus a Crustacean.t—Dr. A. 8. Packard, jun., who has also
devoted much attention to this form, replies to Professor Lankester’s
paper on the Arachnid nature of Limulus,t maintaining that his
conclusions are untenable. The criticism is not susceptible of
abstract beyond the statement that Dr. Packard considers Professor
Lankester has not correctly described the differences between the
brain and the thoracic ganglionic mass of the scorpion and Limulus,
that in the morphology of the brain the latter much more nearly
approaches Apus and other Phyllopods than Arachnids, that four of
the six segments described by Professor Lankester between the
sixth abdominal segment and the spine are imaginary, as is also his
view that the scattered simple eyes of the scorpion are really com-
pound eyes, and some attempts to homologize parts of the scorpion
with Limulus.
Segmental Organs in Isopoda.t—Lereboulet in 1850 concluded
that the Cloportides (Wood-lice) are allied to the Spiders, by the
existence of special glands, secreting a silky substance ; but M. Huet
considers that the facts he has observed would equally enable them
to be referred to the Annelida or Myriapoda.
There are glandular organs not only in the caudal region of these
animals, but in each of the seven segments of the body. They are
absent from the head. They open in the superior portion of the
* Engl, Mech., xxxiv. (1882) p. 496.
+ Ann. and Mag. Nat. Hist., ix. (1882) pp. 369-74.
{ Comptes Rendus, xciy. (1882) pp. 810-11.
338 SUMMARY OF CURRENT RESEARCHES RELATING TO
epimera, on each side, in a sieve-like aperture. In the tail, the
reduced segments do not show the “sieves,” the glands undergoing a
sort of concentration, and all opening together in a slit pierced with
holes arranged in linear series. This slit is on the external side of
the external urostyle.
Each of these glands consists of cellular elements of comparatively
gigantic dimensions, some of them measuring 0°2mm. LEach is com-
posed of a knobbed, indented, lobate body, always enclosing two
large, symmetrical, granular nuclei, close to one another. Hach
nucleus contains a nucleolus, also very granular. The nuclei are
coloured red by carmine, and blue by iodized serum. Between them
winds a sort of vestibule, from which issues a canal, filled with the
secreted substance. The canals do not anastomose, but end separately
in one of the sieve-like apertures, or in the slit of the urostyles.
This arrangement is found in the greater part of the terrestrial
Isopoda, Porcellio scaber, Oniscus murarius, Armadillo, and Ligia.
_ Porcellio pictus has only the caudal glands. It is not found in any
aquatic Isopod, nor in Ligia oceanica, nor in Anilocra, Idoteide, or
Asellus aquaticus.
Bopyride.*—R. Walz deals in order with the different parts of
the organization of these parasitic Crustacea ; the cuticle of the male
is said to be thicker than that of the female; the larval stages do not
differ from one another in any important particulars; the changes
early undergone by the mouth-organs are noted; later on, the oral
cone calls to mind the suctorial proboscis of some Siphonostomata.
On the inner side of the base of the first five pair of legs are deve-
loped the brood-lamelle, which acquire their full size when the
female reaches maturity; they are always membranous, and their
chitinous cuticle is produced, as a rule, into short denticles. Vary-
ing a good deal in form, they determine that of the brood-pouch. The
gills are thin, lobate, rarely tubular appendages ; they always decrease
in size from before backwards, and are, as a rule, better developed in
the female than in the male; in the latter, indeed, they are often
nothing more than small protuberances on the abdomen which dis-
appear with age. Hach lamella consists of two folds with a very
narrow intermediate space; from one wall there pass to the other
supporting bars, which have a homogeneous clear appearance and are
to be regarded as cuticular structures. The digestive apparatus
exhibits special characters, in correspondence with the parasitic habits
of its possessors; the fore-gut is first enlarged and then narrowed to a
tube; it leads into a wider portion, and the whole is so arranged as to
act as a suctorial pump. The fore-stomach is enlarged into a crop,
and the inner wall of some forms is provided with a number of
processes, by means of which there is a considerable increase of sur-
face ; but this peculiarly arranged crop is, it is curious to note, found
uly in the female and not in the male, where the corresponding
region forms but a very slight enlargement. The mid-gut likewise
is much smaller and narrower in the male than in the female. The
salivary glands which have been described by Cornalia and Panceri,
* Claus’ Arbciten, iv. (1882) pp. 125-200 (4 pls.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 339
were not detected by the author. There is a pair of hepatic tubes
which give rise to numerous enlargements and lobes, but no lateral
enlargements are to be found in the males.
There is a well-developed heart in the form of a rounded oviform
sac; in the irregularly developed female there is to be detected not
only an asymmetry of form, but also of the position of the clefts.
The wall of the aorta is formed by a clear transparent membrane,
which never exhibits contractions; though efferent vessels are present,
there are no afferent ones; a septum of connective tissue extends
transversely below the enteron, just as in the Phronimida.
The nervous system has only been examined by Rathke, and by
Cornalia and Panceri; in its morphological relations it differs com-
pletely from that of the other Isopoda; the brain is extremely
reduced, as are all the parts connected therewith ; in the third thoracic
segment is a reduced unpaired ganglionic chain, formed by the short-
ening of the longitudinal commissures and the fusion of the ganglia;
in this seven distinct elements may be made out. The peripheral
nerve-trunks have a somewhat peculiar ganglionic relation. Those
of the first go directly from their proper ganglion to the most anterior
thoracic segment; the second pair passes below the third ganglion,
and the next near the sixth, or, in other words, just in front of the
termination of the nervous plate. The sensory organs are either a
great deal reduced or have completely disappeared; in the young
free-swimming male there are eye-spots and jointed, paired, antenne ;
there is some question as to whether eyes can be said to exist in the
female; at any rate true optic nerve-fibres are not always to be made
out. The larve have reddish pigment-specks at the sides of the
cephalic lobes, which are covered over by the base of the outermost
pair of antenne.
Not only do these parasites retain a separation of the sexes, but
there is a well-marked sexual dimorphism ; the ovaries are dorsally-
placed tubes, not fused with one another, the appearance of which
varies with the age and condition of the animal; at first they are
straight, but they gradually become provided with a number of lateral
saccular diverticula, which project into the thoracic segments; the
orifices of these organs are found, as might be expected, on the inner
side of the bases of the fifth pair of legs. The wall of the ovarian
tube is a thin membrane, invested internally by an epithelium and
completely transparent. The male organs have much the same
general characters as the female; and the tube functions both as
germinal gland and receptacle for the sperm; the spermatozoa are
very small granules, immense numbers of which are collected into
one mass. No formation of spermatophores, or any copulatory organs
have been detected.
After referring to the musculature and the connective tissue, the
author passes to the second part of his essay, where he deals with
the classification of the Bopyride: owing to the small number of
Species it is not necessary to form any subfamilies; the difficulties
of definition lie in the fact that the form of the body, the number of
antennary joints, and the arrangement of the gills differ so much in
the two sexes.
340 SUMMARY OF CURRENT RESEARCHES RELATING TO
Vermes.
Peculiar mode of Copulation in Marine Dendrocela,*—Claparéde
has already shown that in the genus T’hysanozoon there are two penes
and two male genital orifices, but only one orifice in the female. This
observation has not only been confirmed by A. Lang, but much ex-
tended; he having found at Naples forms with nine or even fifteen penes.
It is obvious that these could hardly have been intended to be intro-
duced into the single vagina. The true signification of the contrivance
was elucidated by the observation of the copulatory process in several
species of Proceros—the penis was thrust indiscriminately into the
body of the female, and through the wound thus formed the semen
flowed into the oviduct which is distributed throughout the body.
The female organ therefore serves only as an exit for the eggs.
Classification of the Nematohelminthes.;—Dr. L. Orley pro-
poses to establish three suborders, to which he would give the names
of Nematentozoa, Rhabditiforme, and Anguillulide; the last are
fitted for a free life, and are characterized therefore by the presence of
circumoral bristles, lateral circular markings, and a caudal sucker ;
the Rhabditiforme are intermediate, for, while they lack the charac-
ters just mentioned, they resemble the free-living and differ from the
parasitic Nematentozoa in having a thin cuticle, and a single straight
tube, as well as in the fact that their nervous system is either entirely
absent, or consists only ofa few fibres. So, again, while all Nematoids
have free larve, those of the parasitic group perish unless they enter a
host ; the Anguillulide do not so enter, but develope in mould or water,
while the Rhabditide may or may not enter into hosts. There is an
arrangement of the genera,.with short diagnoses, and two new species
of Filaria, F. spiralis and F., ecaudata, are described.
Relations of the Platyhelminthes{— Dr. A. Lang gives an
account of the results to which he has been chiefly led by his
study of Gunda segmentata.§ Considering first of all the Polyclades
as creeping Ctenophores, he points out that, in his opinion, the
Celoplana of Kowalevsky is not intermediate between the Ctenophora
and Planaria, but is a true creeping Ctenophore; this form is remark-
able for being flattened, for having the ctenophoral plates absent, and
for a complete investment of cilia. The fact that external conditions
can produce such great changes prevents us from giving any importance
to such characters as these, when we compare the two groups. To
most of the internal points of resemblance between them attention
has already been directed ; but with regard to the development, we
may note that Selenka has lately pointed out the striking similarity
he has found in the earlier stages; and the observations of Lang
are confirmatory of the fact that the embryo of the Polyclades
is at first radial, and that it is only later that it becomes bilaterally
symmetrical.
* Arch. Sci. Phys. et Nat., vi. (1881) p. 308.
+ Ann. and Mag. Nat. Hist., ix. (1882) pp. 301-18.
+ Arch. de Biol., ii. pp. 533-52.
§ Sce this Journal, ante, p. 197.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 341
It is pointed out that G. segymentata presents many features of
striking resemblance to certain Hirudinea, and especially the Rhyncob-
dellide ; the pharynx, like that of the Triclades, is contained in a
special cavity ; the intestine has always a number of paired diverticula,
the number of which is constant for a given species. The two last
are always longer than the others, and often have, on their outer
side, secondary outgrowths. ‘These may be compared to the lateral
and posterior branches of the intestine of the Triclades. The
terminal intestine, the posterior dorsal anus, and the large sucker are
to be regarded as formations special to the Hirudinea.
There is likewise a considerable resemblance as regards the
excretory system, but the collecting organ of the Hirudinea is, again,
a new formation; in the adult leech there is no connection, as we
know, between the excretory system and the enteric diverticula, but
in the embryos of Clepsine there is evidence that this system is
- developed from the epithelium of these diverticula. Striking resem-
blances are also to be seen in the generative system. The ventral
ganglionic chain of the Hirudinea does not appear to be so very
different, if we suppose that it is comparable to the two longitudinal
nerve-trunks of Gunda connected at segmental intervals by simple
commissures.
The musculature of the Hirudinea is mesenchymatous; the uni-
cellular muscular fibres consist of an axial substance with a nucleus
and a contractile sheath, just as in Guwnda there is a dorsal muscula-
ture consisting of an external layer of transverse muscles, and an
internal one of longitudinal fibres. In addition, there are dorso-
ventral muscles which cannot be distinguished from the muscular
dissepiments of Gunda, and, just as in that form, there is no enteric
muscular layer. The body-cavity of the Hirudinea is not an entero-
cole, but a schizoccele, formed by the vascular and lymphatic systems
which are in communication with one another, and are developed, as
Prof. Lankester has shown, by the liquefaction of the parenchymatous
cells of the mesenchyma. Were the diverticula of the intestine to
be detached from it, we should have a true enteroccele, which would
then give rise to the epithelial musculature of the wall of the body
and of the intestine, the excretory organs would thus acquire their
primitive relations to the diverticula, and would serve, at the same
time, for the evacuation of the generative products. It is probably
along some such lines as these that the Oligochxta and Annelids
have been developed from a Leech-like form.
In connection with this subject Dr. C. Chun* points out that,
though there are several points in common, there are also some
important differences in the development of the Ctenophora and
marine Planaria. In both there are four small and four large
cleavage-spheres, and the gastrula is formed by epiboly. While,
however, the rapidly multiplying small cells of the Ctenophora
represent the rudiments of the ectoderm and mesoderm, in the
Planaria there arise four primitive mesodermal cells, which alone
form the mesoderm. He is not certain that the resemblances point
* Biol. Centralbl., ii. (1882) pp. 5-16.
342 SUMMARY OF CURRENT RESEARCHES RELATING TO
to genetic relationships, and suggests that these observations may
only be the commencement of the raising of a new set of problems.
Entozoa confounded with Trichine.*—P. Mégnin points out that
Trichina spiralis is not the only worm which may become encysted
in the peritoneum or the muscles ; and after showing how various
naturalists have been led to speak of Trichine where none exist,
he gives an exact account of the character of T. spiralis. It is an
extremely delicate, filiform worm, with a very narrow anterior
extremity, in the centre of which is the small round mouth; the
posterior end is truncated, and has the anus in its centre. The in-
testinal tube is straight, and has a distinct cesophagus, stomach, and
rectum. The agamic encysted forms are chiefly found in the
muscles of animal life, but they are sometimes to be seen in the
adipose tissue and in the muscles of the intestinal walls. Around
the spherical space occupied by each coil, there is a deposit of
colourless granular matter, which is more abundant towards the two
poles, and has generally an elongated conical form. A single cyst
or capsule rarely contains more than one worm. Later on, the walls
of the cysts become incrusted with calcareous salts, within which
the Trichina may continue to lie. After its death fatty degenera-
tion occurs.
The European mole is often in spring infested, on the external
surface of its stomach and intestines, with small cysts, in which a
worm is coiled up. The integument of this parasite is markedly
striated, the mouth has a papilla, and the body is more cylindrical
than that of Trichina; in addition to these and other characters
there is a conical tail. This is the larval stage of Spiroptera strumosa.
In some Spanish and other lizards there may often be found a
number of cysts scattered throughout the body; here again the
anatomical characters are those of Spiroptera rather than of Trichina ;
and, in fact, the organism is S. abbreviata. Other forms from other
animals, including the frog, are described ; one belongs to the genus
Dispharagus, all the rest to Spiroptera. The author justly points out
that a careful comparative study should be made on all occasions
when it is stated, or believed by the observer, that he has to do with
the genus Trichina. The paper will be very useful to all who are
engaged in researches of this kind.
Life-History of the Liver Fluke.|—Professor R. Leuckart states
that his search for the young of Distomum hepaticum has at last
been rewarded ; specimens of what he regarded as Limneus minutus
were obtained from Dresden, and many of these were, after a few
days, found to have in their respiratory cavity, and generally, near
the kidney, a number of the embryos.with which he had in vain
attempted to infect larger snails. More or less rounded bodies were
found more or less closely packed together, and attached by a
delicate cellular envelope to the operculum; there could be no doubt
as to the relation of the parasite to the embryo, not only was there
* Bull. Soc. Zool. France, v. (1881) pp. 189-98 (2 pls.).
+ Arch, f. Naturgesch., xlviii. (1882) pp. 80-119 (1 pl).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 343
the characteristic cephalic process, but the simple «-shaped eye-dot
was converted into two irregular black dots, while the internal
changes that were seen indicated a metamorphosis into the sporo-
cyst stage.
When the embryo escapes from its shell it contains all its germ-
cells, which occupy the hinder portion of the body-cavity, while the
anterior half is filled with a granular mass, which may be looked
upou as the rudimentary enteron. At this stage the embryo has, in
its general structure, so striking a resemblance to the Orthonectida
of Giard, that the author is of opinion that these forms, just like the
Dicyemidz, must be regarded as of the Trematode group; the fact
that they never pass beyond an embryonic condition, even although
they exhibit a complete differentiation of the sexes, need not cause
much astonishment, if we reflect that the sexually mature entozoa
of a large number of Invertebrates are, after all, to be morphologi-
cally referred to more or less developed larval forms; in addition to
this, we may note that there is not really the difference which there
is ordinarily supposed to be between the germ-cells of the Trematoda
and the female generative products. After swimming actively about
for some time, the embryo makes its way into a snail, and generally
into the respiratory cavity. As arule, the ciliated investment is now
lost, and the two eyes become separated; the form of the body
meanwhile ceases to be conical, and becomes more or less compressed.
The loss of the cilia is, of course, the expression of the commence-
ment of the parasitic life; before it begins the animal makes some
powerful peristaltic movements, which loosen the cells. As soon as
the animal has completely entered into a resting-period, a thin layer
of clear cuticular substance is secreted around its outer surface ; this
forms a kind of cyst, which is perfectly adapted to the form and
changes in form of the body. Increase in size chiefly affects the
germinal cells, some of which rapidly, and others less rapidly, divide
repeatedly, and give rise to larger cell-aggregates; this growth leads
to the enteron being pushed forwards, till it forms a kind of inner
cap for the cephalic end of the body, the eyes become altered in
position, and the number of the refractive granules increases.
All the- germinal cells, however, do not undergo division and
further development, a large number remain in their earlier con-
dition; so again, during the first days of parasitic life, a number of
sporocysts die down; some of those that become further developed
would seem to have the power of dividing; at any rate the increase
in the size of these parasites is less an active than a passive pheno-
menon ; it is the consequence merely of the regular growth of the
germ-spheres, which reacts on the form of the embryo; the walls of
the body now become thicker, and lose largely their power of con-
tractility; the ciliated funnels would seem to disappear, and even
the eyes become obscured ; the last signs of the rudimentary enteron
are now also lost. Some of the germ-spheres contained within the
body begin to elongate, till they form tubes of some considerable size,
presenting a specific internal and external organization and forming
definite creatures. The inequality in the rate of development of the
344 SUMMARY OF CURRENT RESEARCHES RELATING TO
germs which was noted is now more distinctly manifested by the
presence of organisms at very various stages of development. To the
author’s great astonishment he, found that the products of the -
sporocyst were not Distomata, but Rédie ; these, when free, are about
0:4-0:7 mm. long, but are capable of considerable contraction and
extension ; a head, median region, and tail-end may be distinguished ;
the two former are separated sharply from one another by a prominent
encircling ridge, while the body is distinguished from the tail by two
blunt projecting processes, developed from the ventral surface. The
tail is bluntly conical. The lips surrounding the mouth serve as
attaching organs. The organization of the Kédia presents very con-
siderable resemblance to that of the embryos, the organs being only
more strongly individualized and the elementary parts more distinct,
in correspondence with the larger body and higher function. The
encircling ridge may be looked upon as a kind of skeletal girdle,
which serves as the point of attachment for the retractors of the head
and pharynx. As to the mode of development of this Rédia, the
author believes that it passes through a gastrula stage; though some
points were made out, the history of the germ-spheres could not be
followed. Here then, unfortunately, this part of the history comes to
an end; luckily some other snails were obtained in which were found
three Rédiew; two of these contained Cercariz, but a third had a tail-
less Distomum which is believed to have been a young D. hepaticum.
In conclusion, some remarks are made on the small Lymneids
which are believed to be the hosts.
Excretory Apparatus of Turbellaria.* — In continuing his
studies,t P. Francotte points out that Hallez denies the existence
of the excretory canals in the genus Monocelis, while Schultze and
others distinctly affirm their existence. The author has been able
to confirm the latter doctrine, so far as it applies to the presence of
these canals, but he has not been able to detect any communications
with the outer world. On the other hand, he has discovered the pre-
sence of ciliated terminal infundibula, very similar to those of the
Trematoda and Cestoda.
In dealing with the genus Monocelis, it is, first of all, necessary
to take for examination perfectly fresh specimens; there will then be
seen a system of principal canals, fine secondary canaliculi which
form a plexus throughout the whole, and vibratile infundibula united
to the plexus by a canal. There are two pairs of principal canals on
either side of the middle line, two external and two internal ; these
are united with one another by several anastomoses of the same size;
the distinct walls are transparent and very hyaline, but no definite
histological structure could be made out. At certain points there
may be seen a long conical filiform cilium; the canals contain a
transparent liquid in which are some small granulations. The secondary
canaliculi arise from the ciliated infundibula and have a very delicate
wall, of no distinct structure; they are best made out in the anterior
* Bull. Acad. R. Belg., iii. (1882) pp. 88-98.
¢ See this Journal, i. (1881) p. 460.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 345
region; the infundibula are conical, and have, in optical section, a
triangular form; the wall is here again transparent and hyaline. It
is interesting and important to note that in sections of these worms,
though prepared by different methods, no trace of the existing canals
has yet been detected.
The Dendroceela (as represented by Polyceelis nigra) would appear
to be without the secondary canaliculi, the infundibula being connected
with the principal by five canals. The principal canals here form a
plexus and would seem to open to the exterior ; the highly refractive
wall here again appears to be without any definite structure. Through-
out their whole extent there is a continuous vibratile line lining the
canals. The infundibula are conical and their wall is formed by the
walls of the canals into which they open, but the black pigment of
the form examined prevented the author from seeing whether or not
the canals are completely closed.
New Parasites.*—J. Fraipont describes some parasites of Uro-
mastia acanthinurus. Only five Tenie are yet known from any of the
Saurians; the new form, 7’. alata, has two aliform delicate expansions
on the neck ; the transparency of the joints allows of the easy detection
of the two pairs of longitudinal canals belonging to the excretory
system, which extend throughout the whole of the body. In the
terminal segments there were detected a considerable number of eggs,
with a thin but resistent membrane, and each containing a hexacanth
embryo, surrounded by an embryonic envelope.
The presence of an Echinorhynchus is interesting as, apparently, no
species of the genus has ever yet been found in a Saurian; the present
species is called EH. uromasticis. Filaria candazei is a new species
found in the subcutaneous connective tissue and between the different
muscles of the body; the female is much larger and longer than the
male (100-120 mm.). The muscles are arranged on the poly-
myarian type. Special organs in the shape of four pairs of pediculated
appendages bearing each two small papilliform growths on their free
end, are arranged symmetrically on either side of the sheath of
the penis.
Tube of Stephanoceros Eichornii.t—Mr. T. B. Rosseter, on sever-
ing the longitudinal muscles that extend down the peduncle (cutting
the tail through close to the base), saw the Stephanoceros swim out of
the tube at the oral orifice, leaving it intact, and thus confirming the
view of Mr. Slack, as against that of Mr. Pritchard, that it is tubular
and nota solid gelatinous mass. He considers it clear that “itis per-
fectly hollow : there is no attachment between the cell and the creature,
and it is quite as independent of its cell as Melicerta ringens is of its
cell.” The dragging down of the upper portion of the tube is caused
by the teeth of the tentacles overlapping the sides and not from
attachment to the neck of the creature.
Mr. J. Badcock, however, considers that both parties are right in
* Bull. R. Acad. Belg., li. (1882) pp. 99-106.
+ Sci.-Gossip, 1881, pp. 107-9 (6 figs.).
Ser. 2.—Vou. IL. 2A
346 SUMMARY OF CURRENT RESEARCHES RELATING TO
the view they have taken; for, as the result of his own observations,
he finds that when young the tube is hollow, but when old the cavity
becomes filled up with a mucous substance.
Echinodermata.
Structure of Pedicellarie.*—A. Foettinger has examined the
gemmiform pedicellarie of Spherechinus granularis. He finds that
the three more or less ovoid glandular sacs which are formed on
the stalks of these, are surrounded by the common epithelial mem-
brane which invests the whole of the organ. They open to the
exterior by an orifice at their superior extremity, and they alternate
in position with the valves which form the head of the pedicellaria.
After decalcification by means of chromic acid, and staining with
carmine, the following tissues can be seen on making a transverse
section of a pedicellaria at the level of these glands; there is an
external epithelium, containing a large number of pigment-corpuscles,
a layer of connective fibrille which separates and unites the glan-
dular sacs; these have an external layer of flattened muscular fibres,
with an oval nucleus, and these fibres are arranged concentrically
around the orifice of the gland ; the contents of the sac vary greatly,
being in some cases formed of a granular, and probably mucous,
matter which contains refractive corpuscles which swell up under the
action of water, and are, doubtless, modified nuclei; in other cases
the substance is filamentous, but this is ascribed to the coagulating
action of alcohol; this substance swells up considerably on contact
with water, &c.; and this increase in volume, when it happens with an
uninjured pedicellaria, must lead to the outpouring of the contamed
mucus. When certain transverse sections are made, the contents of
the sac are seen to be constituted almost solely of protoplasm with
nuclei and cell-walls more or less intact. In longitudinal sections
some of the glands present a protoplasmic layer investing the base
and the walls. The author would explain these facts by considering
that the glandular sacs are primitively filled by a tissue formed of
polyhedral cells, and making a compact mass. At a certain time
these cells are converted into mucus, and this change goes on until
all the external cells are affected by it.
The three valves which form the head of the gemmiform pedi-
cellaria are pyriform in profile view, and ovoid from in front; the enve-
loping layer is merely epithelium ; below it there is a layer of granular
and fibrillar connective tissue, which is generally very delicate, but is
abundant between the valves, and near their upper surface. Beneath
this tissue we find a glandular sac, which is double above; at the peri-
pheral extremity the two branches unite into a single canal. ‘This
glandular sac would also seem to have its primitive contents formed
of a compact cellular tissue. Hchinus melo and Echinometra subangu-
laris have at the base of the head of their pedicellarie organs which
are very probably homologous with those found on the stalk of S.
granularis. M. Foettinger has also examined the pedicellarie of
* Arch. de Biol., ii. (1881) pp. 455-96 (3 pls.). Bull. Acad. R. Belg., ii. (1881)
pp. 493-504. :
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 347
Diadema setosum and D. mexicanum ; these, which are about 2 mm.
long, are club-shaped and end in a very short and delicate pedicle ;
they enclose three large elongated glands with an orifice at their
upper end; the glands are closely applied to one another, but have
superiorly, where they diminish in size, six separating cavities which
may be looked on as the homologue of the head of the pedicellariz of
S. granularis. In Mespilia globulus the pedicellarie are excessively
small and very numerous. In Strongylocentrotus lividus and S. dro-
bachiensis the gemmiform pedicellariz have a stalk which has consi-
derable resemblance to that of the ophiocephalous and tridactyle
pedicellarie. When we compare S. granularis with Echinometra and
Diadema we find that in the first the glands and head are equally
developed, that in the second the glands are rudimentary, and that
in the third it is the head which is rudimentary.
The author, not having been able to make any original observa-
tions on living forms, accepts the views of Sladen, who was the first
to direct pointed attention to this subject.
Circulating Apparatus of Starfishes.*—E. Perrier and J. Poirier,
after noticing the accounts of earlier observers, in which there is a
large amount of very perplexing contradiction, state that they find
that the vascular apparatus described by Ludwig in the partition of
the infrabrachial canals has no existence, that the partition is not
continuous, but that it is reduced at certain points to a vertical
lamella while at others it presents distinct foramina. The body
adherent to the hydrophoral canal, where Ludwig sees a plexus of
vessels and which he regards as being the heart, is (as Jourdain
showed in 1867) nothing but a gland; the same has been shown to be
the case in the common sea-urchin, and Koehler has found the same
to be true for the Spatangide. As the Ophiuroidea present a similar
structure, we may say that, in all Echinoderms, this so-called heart
is a simple gland.
The system of lateral branches described by Hoffmann as arising
from the infrabrachial canals, has been detected, but a different
account is given of its relations. These lateral branches do not
curve round the ambulacral pore, but pass straight to the edge of the
ambulacral groove; what Hoffmann took for the second branch of
the horse-shoe is a fresh canal, independent of and identical with
the first; and these two canals pass, parallel to one another, to
the edge of the arm; there they bifurcate and the two neighbouring
branches together pass through a foramen between two contiguous
ambulacral, and the adjacent adambulacral pieces. In these foramina
the two branches unite to form a common branch, which opens
directly into the general cavity. There is always a similar hole
between two contiguous ambulacral pieces, so that the infrabra-
chial canals always communicate with the general cavity by as many
holes as there are ambulacral pieces. The infrabrachial canals and
the branches which they give off are, therefore, merely dependences
of the general cavity, divided into two communicating parts by the
* Comptes Rendus, xciy. (1882) pp. 658-61. : -
Ly, Beg
348 SUMMARY OF CURRENT RESEARCHES RELATING TO
tentacular canals, and the system of ambulacral pieces. These canals
also present a mode of partition which is remarkably like what is
found in the brachial cavity of the Comatule; this mode is alone
found somewhat late in the Crinoids, and we see that there is, there-
fore, in them “an accidental character” which contrasts strongly with
the almost absolute fixity of the relations of the ambulacral appa-
ratus. “This last is the essential and dominant character in the
organization of an Echinoderm.” The authors also find that the
integument of the infrabrachial canals is formed of small bipolar
cells, the swollen portions of which are near the external surface.
Genital Passages of Asterias.*—S. Jourdain describes the pre-
sence of five vasculiform ducts, lying below and applied to the
internal face of the dorsal integument, the sides of which form a
pentagon. The angles of the pentagon point to the interradial septa,
and a vessel, embracing each septum, establishes a continuity between
the branches which correspond to the sides of the pentagon. This
vasculiform pentagon was regarded by Tiedemann as a dorsal venous
circle, but from each septum there are given off two branches which
become connected with the appended genital glands, and they are the
only ones which are given off from it. The author is of opinion that
this pentagon has no relation to the proper vascular system. The
vessels do not have the relations of blood-vessels, but they are in
communication with the interior of the gland and its diverticula; in
other words, they are disposed as the excretory canals. The vasculi-
form dorsal plexus varies in size with the activity of the genital
glands, and its walls are provided with muscles, while the internal
ciliated surface has a projecting fold of glandular tissue. At the
point of attachment of the enlarged interradial septum, which corre-
sponds to the madreporic plate, the ducts of the pentagon open into an
elongated fusiform sac, which is invested in an elastic membrane
containing muscular fibres. At the extremity of this sac there are two
brownish pyriform bodies, which are in connection with the canals of
the pentagon ; these, with the sac and its projection, are what most
writers have considered to be the heart. They are not so, but merely
dilated continuations of the pentagon. The fusiform sac opens into
a circum-oral ring, to which are attached small paired globular bodies,
almost similar in histological structure to the pyriform bodies. An
orifice, of extremely small size, and very difficult to detect, is to be
found where the sac is continuous with the circum-oral ring; so that,
Asterias, just as in Holothurians, the sperm and the ova are passed to
the exterior by a pore in the circum-oral circlet, and not by interradial
perforated plates.
E. Perrier and J. Poirier state,t however, that specimens of
Asterias glacialis, alive and depositing ova, are seen to have their ova
escaping by ten groups of small holes, set a little above each inter-
radial angle ; each group contains three to six orifices; in specimens
that had been opened from the dorsal surface no ova were to be found
* Comptes Rendus, xciy. (1882) pp. 744-6.
t Ibid., pp. 891-2,
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 349
in the circular dorsal canal, or in the tubular pouch surrounding the
hydrophoral canal; this pouch serves as a means of communication
between the dorsal and ventral circular canals, and is really nothing
more than one of the spaces formed by the peritoneal membrane, and
enlarged ; but neither it nor the dorsal canal have anything to do
with the excretory apparatus of the generative system.
Celenterata.
Clavularia prolifera.*—After a description of this new Alcyon-
arian, G. v. Koch discusses the mode of connection of the buds with the
trunk ; he points out that it is a remarkable fact that these buds are
' not mere outpushings of the body-wall of the mother-polyps, but that
at the base of each bud there is a canalicular network in the thickened
connective substance of the mother, by which the two polyp-cavities
indirectly communicate with one another. Discussing the question
of its origin; the author shows that, if it is secondary, or if, in other
words, the young polyp first developes as a simple evagination, and
gives rise to the plexus by a partial fusion of the intermediate sub-
stance, it would bea structure which owed its existence to adapta-
tion, or had only a physiological significance, such as might be
explained as due to the more or less complete isolation of the polyps.
On the other hand, if it is primary, or, if it gave rise to the young
bud, then we should have to seek its morphological significance, and
might compare this canalicular network with the nutrient canals of
the Gorgonida.
This important question could not be decided on the preserved
specimen which the author has-examined, but a study of some allied
forms shows that in this group of corals the digestive cavities of
the buds never open directly into that of the mother, and that
there are a series of intermediate stages from those in which the
polyp-buds are derived from simple stoions, and those in which the
stolons form canals in the thickened mesoderm, and those, lastly,
in which the thin partition between the bud and the mother is per-
forated by small orifices. We may therefore conclude that the more
or less incomplete separation seen in the Alcyonaria has a certain use,
and that it is not an adaptive arrangement, but one which may be
referred to the formation of the stolons; the canalicular network in
the mesoderm of the mother-polyps, which lies at the base of the
buds and connects them with the mother, is a stolon-formation (in
its widest sense). And, further, we find that in the Alcyonaria
asexual reproduction is never effected by division or direct gemma-
tion, but always indirectly, or by stolons or structures homologous
therewith.
A study of the new species throws some light on the horny sheaths
of the spicules, and their relations to the ectoderm, for we find
that the younger spicules are always invested in a protoplasmic
nucleated sheath, which may also be frequently made out in older
examples, where we find cells connected by pairs and having within
* Morph. Jahrbuch, vii. (1881) pp. 467-87 (2 pls.).
350 SUMMARY OF CURRENT RESEARCHES RELATING TO
them the young spicule. The doctrine, then, of Kowalevsky, that the
spicules arise from cellular elements, may probably be extended to
all the Alcyonarians. And the same would seem to hold for the
horny sheaths. These cells found in the mesoderm would seem to
have been derived from the ectoderm, whence cells have been observed
to wander into the middle layer ; as this has never been noted with
regard to the endodermal cells, we may conclude that the hard skeletal
parts of the Alcyonaria, whether spicula or horny sheaths, are
derived from the ectoderm.
Porifera.
Sponges of the Gulf of Triest.*—In his seccnd paper on the
marine fauna of the Gulf of Triest, Dr. E. Graeffe deals with
the Spongiarie; with which O. Schmidt has already dealt. It
is pointed out that sponges have but few enemies; some of the
species of Doris, Doriopsis, and Fissurella attack their outer layers ;
on the other hand, they have a number of parasites, Algw and
Chetopod Annelids being the most conspicuous. Gammarida are
also not unfrequently found. Some silicious sponges have their
outer surface affected by small Aphroditeide and by Hydroid
Polyps.
i the list given by the author especial attention is directed to
the places in which they are found, and their time of reproduction,
with some notes on the localities of the ova and larve.
Spongiophaga in Fresh-water Sponges.t—Mr. E. Potts insists
that Mr. Carter is mistaken in considering that the slender curling or
twisted tendrils { of the statosphere of fresh-water sponges of the
genus Carterel’a § are parasites, as described by him under the name
of Spongiophaga Pottsi.|| Prof. Leidy, by whom they were examined,
says that “ there can be no question as to the tendrils being part of
the structure of the statoblast—homogeneous extensions of its inner
capsule.”
The function of the tendrils is apparently to meet the emergency
occasioned by the looseness of the skeleton structure, from which
the sarcode-flesh dying early washes away, most of the spicules soon
following in the winter floods. The eggs are thus left to the pro-
tection of the tendrils, which lap them together, bind them to the
remaining spicules or the roots of water-weeds or shore plants, or
assuming the réle of the hair which the plasterer uses, bind the
deposited silt about them, and both to the stones, where they await the
appointed time for a new growth. The resemblance in material
structure of these tendrils to that of the specialized hooks of some of
the Polyzoa is very striking.
Mr. Carter, as the result of subsequent examinations,f agrees with
Mr. Potts’ view as to the filaments being in reality cirrous appendages
on the statoblasts and not Spongiophaga.
* Claus’ Arbeit., iv. (1882) pp. 313-21.
t Proc. Acad. Nat. Sci. Philad., 1881, pp. 460-3.
t See this Journal, i. (1881) p. 613.
§ Ibid., p. 901. || Ibid., p. 901.
4 Ann. and Mag. Nat. Hist., ix. (1882) pp. 390-6.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 351
New Fresh-water Sponges.*—Mr. E. Potts describes three
more curious fresh-water sponges. One (Meyenia crateriforma) is
of a very delicate structure ; its framework of skeleton spicules is
exceedingly meagre, and slightly bound together, scarcely amounting
to a mesh system, and the numerous small white statospheres are
found in recesses far larger than themselves. Another (Heteromeyenia
ryderii) forms beautiful green masses, often four to five inches in
diameter, and about a quarter of an inch in thickness. The surface
is irregular, occasionally rising into rounded lobes; the efferent
canals are deeply channelled in the upper surface of the sponge, five
or six sometimes converging to a common orifice. The statospheres
are numerous and rather small. There are two series of birotulate
spicules. The third species belongs to the genus Tubella. This
genus, established by Carter, contained only four species, all from the
Amazon river. The new species is small, encrusting, and has been
named TJ. pennsylvanica. The skeleton spicules are arranged in a
simple series of single non-fasciculated spicules, in the interspaces of
which the statospheres are abundant. These spicules are very vari-
able in size and shape, but all are entirely and coarsely spined. The
dermal spicules seem absent.
Protozoa.
Organization of the Cilio-flagellata.t—R. S. Bergh gives an
account of the Cilio-flagellata observed in the Little Belt and in the
fresh waters of Denmark; the first part containing “ History” and
“ Bibliography,” the second a description of ten genera and twenty
species, and the third Phylogeny. ‘The chemical composition of the
various parts of the body is fully dealt with so far as that is possible
by the use of reagents, as well as the anatomical structure. Seventy-
three figures show what great variation is presented by certain forms,
and how difficult it often is to define the limits of the species.
The body of all Cilio-flagellata is bilaterally asymmetrical,
differing remarkably, however, in the various representatives ; some-
times it is compressed from front to back (Diplopsalis lenticula,
Glenodinium Warmingii), sometimes from above downwards (Ceratium,
Peridinium), and sometimes laterally (Dinophysis, Amphidinium, Pro-
rocentrum). It may be drawn out into horns (Ceratium, Peridinium
divergens) or may be destitute of any.
They possess either a lorica (cell-membrane) (Ceratium, Proto-
ceratium, Peridinium, Protoperidinium, Dinophysis, Diplopsalis, Gleno-
dinium, Prorocentrum), or are naked (Gymnodinium, Polykrikos). The
membrane consists either of cellulose or a similar hydro-carbon, and is
coloured by chlor-iodide of zinc, pale violet (Ceratium, Perid. tabu-
latum) or intense red (Perid. divergens, Protoperidinium, Diplopsalis), or
even pale red (Prorocentrum, Glenodinium cinctum). Those forms
which have been closely examined do not contain silica. The more
minute structure of the cell-membrane varies much; it is either
transparent and structureless (Glenodinium) or ornamented with
* Proc. Acad. Nat. Sci. Phila., 1882, p. 12.
+ Morph. Jahrbuch, vii. (1881) pp. 177-288 (5 pls. and 1 fig.).
352. SUMMARY OF CURRENT RESEARCHES RELATING TO
reticulately arranged ridges (Ceratium cornutum, and C. hirundinella,
Dinophysis), or the ridges do not form a network, but run more
irregularly, pores also appearing (Ceratium tripos, C. furca, C. fusus) ;
finally we find a division by bands into a number of plates of various
sizes with smaller intermediate strie#, so that the plates show the
reticulated structure, the bands on the contrary being transversely
marked (Peridinium, Protoperidinium, Diplopsalis) ; in Prorocentrum
(apparently) the membrane consists of two cuirasses, which are
perforated with fine pores.
The protoplasm is apparently always separated into ectoplasm and
endoplasm, which both show very varying differentiation. In the
cuirassed forms the ectoplasm is always quite structureless and homo-
geneous ; in Gymnodinium and Polykrikos, the most highly developed
forms, it shows many peculiarities; in G. gracile it is very much
wrinkled and folded, and in G. spirale it contains muscular fibrille
in its inner layers ; in Polykrikos trichocysts are developed in it. The
endoplasm sometimes contains, at the same time, chlorophyll, and
diatomin and starch, or some similar amylaceous matter (Ceratiwm,
Protoceratium, Perid. tabulatum, Protoperid. Michaelis, Glenodinium,
Dinophysis acuta, Prorocentrum), which indicates a mode of nutrition
similar to that of plants; sometimes these substances are wanting,
and the body contains digested organisms (Gymnodinium, Polykrikos),
which indicates that alimentation takes place as in animals; finally,
there seem to be some forms which are nourished neither by the
agency of chlorophyll (the assimilation of carbonic acid) nor by
animal matter, as we find in their endoplasm neither the above-
mentioned colouring matter nor foreign organisms (as in Protoperid.
pellucidum, Perid. divergens, Diplopsalis lenticula, Dinophysis levis).
The endoplasm in Perid. divergens, Diplopsalis lenticula, &e., is
coloured slightly red ; in the former it usually contains little drops of
red-coloured oil. No contractile vesicle can be pointed out with
certainty. In all the forms in which the nutrition could not be seen
to be either assimilative or purely animal, a vesicle is found which
often communicates with the outer world through the flagellum-
furrow and a narrow canal, but is sometimes separated from it;
probably its function is to take in sea-water (with nourishment).
The nucleus is generally single; only in Polykrikos we find four
(larger) nuclei. Those of the Dinifera consist of a fine granular
substance containing no nucleoli and colouring bright pink when
treated with picrocarmine (after alcohol). Only in Polykrikos is
there found a second sort of smaller nucleus (perhaps “ primary
nucleus” in the same sense as in the Ciliata), The nucleus of
Prorocentrum still needs a closer examination.
The locomotor apparatus, the special characteristic of the Cilio-
flagellata, consists of long, powerful flagella and smaller cilia. These
cilia spring either directly from the anterior end of the body (Proro-
centrum), or are arranged in one or two contractile rows in a transverse
furrow formed by two projecting plates or ridges (Dinifera). The
furrow lies either at the anterior extremity of the body (Dinophysis,
Amphidinium), or about the middle (the other forms) ; in Gymnodinium
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 3593
spirale it is spirally twisted. The ciliary movement seems to go in one
constant direction, beginning on the left of the ventral surface. In
Gymnodinium there appears to be only one contractile row in the
furrow. In Polykrikos there are eight furrows independent of each
other. The edges of these furrows are interrupted on the ventral side ;
the posterior ones continue in a peculiar system of horns and ridges,
which are either placed close on each other, as on the small ventral
side of Dinophysis, or are separated from each other as a right and
left hand division (Protoperidinium) ; this entire apparatus serves for
limiting the longitudinal furrow. In the other forms either the
horns alone persist (Peridinium), or the ridges (Diplopsalis, Gleno-
dinium), or both are absent (Ceratium, Gymnodinium.) The Flagellum
is inserted either through a wide ventral aperture in the membrane
(Ceratium) or through a narrow fissure in the longitudinal furrow,
either at the anterior pole (Prorocentrum) or the posterior pole
(Amphidinium, according to Claparéde and Lachmann) or in their
neighbourhood.
Of the propagation and development of the Cilio-flagellata little is
known with certainty. We find fission as well as conjugation.
Transverse fission results either in a free-swimming animalcule (as
for example in Polykrikos, in Allman’s Perid. uberrimum), or in with-
drawal into the old membrane (Perid. tabulatum), or finally in certain
eysts, which are either round (Glenodinium cinctum, Gymnodinium
according to Stein) or have peculiar, strange (horned) forms (Perid.
tabulatum according to Stein). Conjugation is especially shown by
Stein in Gymnodinium pulvisculus ; but several of his statements, the
author thinks, require a complete revision. -
Under the head of “ Phylogeny ” the author endeavours to unravel
the relationship of the organisms, even for each genus and species.
The results of such an attempt could not be very definite, for, as he
himself says, we have not the necessary paleontological evidences and
consequently the intermediate forms are wanting that have existed in
past times. The author’s six genealogical trees can therefore only be
taken for what they are worth, that is as a representation of the more
or less intimate relation which we can recognize between certain
forms. It is, however, a clever and convenient method of expressing
one’s views of the affinities.*
According to the author, the Flagellata form a point of departure
from which are developed phylogenetically (diverging on different
sides), the Noctiluce, Rhizopoda and Cilio-flagellata. The oldest
forms of Cilio-flagellata were the Adinida, of which only one living
species (Prorocentrum) isnow known. ‘They acquired small cilia, and
a bilaterally asymmetrical form. There later appeared the ciliary
apparatus, at first posteriorly and then anteriorly limited by the
ridges of the membrane, so that a transverse furrow was formed
(Dinifera) which was originally on the anterior margin (Dinophysis,
Amphidinium) ; then the flagellum was removed from its primary
position posteriorly, whereby a longitudinal furrow was formed, at
first confined by a complicated apparatus of ridges and horns. Still
* Cf, Arch, Sci. Phys. et Nat., vi. (1881) pp. 402-4.
354 SUMMARY OF CURRENT RESEARCHES RELATING TO
later the body became rounded, the transverse furrow moved in a
posterior direction, and the membrane acquired plates, whilst the lon-
gitudinal furrow-apparatus remained entire (Protoperidinium). From
this point began the development in two directions, since on one
side the ridges (Peridinium, Protoceratium, Ceratium) and on the
other the horn-like processes of the longitudinal furrow (Diplopsaria,
Glenodinium) were reduced, and finally the plates coalesced. The
highest division is represented by the Gymnodinida in which sub-
family the membrane is quite abolished, and numerous differentia-
tions of the protoplasm developed. Finally, springing from these,
are forms in which the flagellum is reduced, but in which a cytostom
and cytopyge are differentiated in order to give origin to the Peri-
tricha, the oldest ciliated Infusoria (Mesodinium).
L. Maggi* establishes the occurrence of Ceratium furca Ehrenberg,
hitherto almost exclusively known as marine, in certain lakes of Upper
Italy (Lago di Candia, near Ivrea, and Lago di Annone, in Brianza) ;
at the same time he devotes much attention to the synonymy of this
species and to the history of the investigations into the phosphorescent
powers of the Ceratia. Like Claparéde and Lachmann, he regards
Peridinium lineatum as identical with Ceratium furca. The form was
not observed alive, but only the remains of its tests; among these
occurred in the Lago di Candia, a considerable number somewhat
differently shaped, which the author thinks right to constitute a special
variety, under the name lacustris.
The same writer f gives a list of all the Cilio-flagellata known to
him through literature or by original observation, adding the syn-
onyms and habitats of each form. He retains the following five
genera :—Ceratium (with seventeen species, two of which are fossil),
Peridinium (with thirty species, all recent, two fossil ones also occur),
Dinophysis (seven species ), Amphidinium (one species) and Prorocentrum
(one species). He believes that Claparéde and Lachmann have gone
too far in their reduction of the number of the species, and have
allowed themselves to be guided by reasons which will not bear in-
vestigation. He endeavours to show here, as in another place, that
the Cilio-flagellata were originally derived from the sea, in which even
at the present time they attain so great an importance, and have only
later extended into fresh water. By this means the circumstance is
explained of their inhabiting more particularly the larger fresh-water
lakes, for in these are found conditions resembling to a certain extent
those of the sea. On this view Prof. O. Biitschlit remarks that the author
has not paid attention to Stein’s writings on the Cilio-flagellata, or
he would have seen that Stein distinguishes three additional genera,
Gymnodinium, Hemidinium, and Glenodinium, but is inclined to remove
the genus Prorocentrum from the group.
L. Maggi § further arranges together all the Cilio-flagellata known
* Bollet. Scientif., i. (1880) pp. 125-8. Cf. Zool. Jahresber. Neapel for
1880, i. p. 167.
+ Op. cit., ii. (1880) pp. 7-16. Cf. tom. cit., p. 167,
+ Tom. cit., p. 167.
§ Rendic. R. Istit. Lombard. xiii. (1880) p. 20. Cf. Zool. Jahresber. Neapel,
tom. cit., pp. 167-8.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 350
to him through the literature of the subject, according to their mode
of occurrence. Thus the forms hitherto found in the different seas
are enumerated, after which a catalogue is given of those belonging to
fresh water, according to the manner of their occurrence in lakes,
marshes, streams, ditches, &c.; and finally a list of those forms which
have been hitherto found in both sea and fresh water. These last
include four forms, viz. Ceratium tripos Ehrb., furca Ehrb., Peridinium
spiniferum Clap. and Lachm. (according to Maggi’s observations), and
Prorocentrum micans Ehrb. The paper concludes with an enume-
ration of the known fresh-water forms, arranged according to the
different countries in which they occur, and going so far as to give
for each form the particular locality in which observers had met
with it. From this section may be specially selected the fact that
the author records Peridinium pulvisculus, KEhrb., spiniferum Clap.
and Lachm., tabulatum Schm., as well as Ceratiwm longicorne Perty,
as found by him in Upper Italy. It is unnecessary to go more fully
into Maggi’s results, as he has made no attempt to examine closely
and compare the forms described by various writers, in order to
decide their claims, but contents himself with simply enumerating
them.
Infusorian with Spicular Skeleton.*—R. S. Bergh has obtained
large quantities of the Infusorian described by Claparéde and Lach-
mann under the name Coleps fusus, in the open sea off the Small
‘Belt (Denmark). The peculiarities which he has observed in this
Species appear to him sufficient to raise it to the rank of a new
genus, whose principal character, distinguishing it from Coleps, is
that the skeletal sheath is not a continuous fenestrated test, but con-
sists of single disconnected spicules. These are parallel to the long
axis of the animal, which has a considerable longitudinal extension
and is pointed at the aboral pole; they are arranged in five
transverse series, showing considerable differences between their
heights. The spicules are provided with short lateral cross-branches,
differing (but not constantly so) in number in the different series; they
constitute an indication of reticulate structure, but, as already stated,
they are not so much developed as to unite the spicules together.
The spicule-elements of the skeleton consist of an organic sub-
stance, and lie imbedded in the peripheral protoplasmic layer. The
cilia are placed above, not between them. A compact crown of cilia
is found at the oral pole. The simple, roundish nucleus lies within
the middle series of spicules.
Contractile Vacuole of Vorticella.t—After an historical intro-
duction relating to the controversy about the presence of a membrane to
the contractile chamber, J. Limbach describes his own observations
on the subject as follows:—In pathologically altered specimens of
Vorticelle, in which their characteristic ciliated organ is swollen up
and the body is detached from the pedicel, the contractile vacuole
* Vidensk. Meddel. Naturh. Foren. Copenhagen, 1879-80, pp. 265-70, wood-
cuts. Cf. Zool. Jahresber. Neapel for 1880, i. p. 170.
+ Kosmos, (Zeitschr. poln. Naturf. Ges. Kopernicus), 1880, pp. 213-21. Cf.
Zool, Jahresber. Neapel for 1880, i. p. 169.
356 SUMMARY OF CURRENT RESEARCHES RELATING TO
becomes more and more distended, so as to include as much as three-
fourths of the breadth of the body. It is scarcely probable that an
unusually thin membrane in connection with the vacuole, if present,
should be able to stretch to such an extent, without bursting, a con-
sideration which appears to furnish additional evidence in favour of
the absence of a membranous wall in the vacuole. Limbach, by
observation of Vorticella cyathina during fission, has been able to
determine the opening of the vacuole into the vestibule, and the
expulsion of its liquid through the opening of the latter. The same
results were obtained from the abnormal Vorticelle above mentioned.
Thus the contractile vacuole constitutes an excretory organ, although
it may at the same time assist in the function of respiration.
Geographical Distribution of Rhizopoda.*—C. Parona gives a
review of the Rhizopoda found by Leidy in North America, of those
met with at the same time in Europe, and finally of those found since
then in Italy. The astonishing agreement in the Protozoan faunas
of districts so widely separated prompts him to raise the question
whether the laws of phylogenetic development are hereby modified, a
question which he answers negatively. This agreement is explained,
according to his view, by the original derivation of the Protozoan
faunas of both regions from a common source, and this must un-
doubtedly have been a marine source.t| The closely similar alter-
ations which have taken place in the circumstances and manner of
life which the primitive Protista-faunas of the two continents have
undergone in the course of ages, are considered by the author to have
gone so far as to cause even the development of closely similar forms.
He is therefore inclined, at any rate in this case, to admit a poly-
phyletic origin of species.
Classification of the Gregarinida.{—B. Gabriel puts forward in
two places a new classification of this group, based on his investiga-
tions into the process of reproduction in the Gregarines. He has
been led to take this course by finding the principles advanced up
to the present time by Stein and Schneider, and depending essentially
upon the morphological peculiarities of the mature forms, to be in-
sufficient ; he therefore believes that a classification can only be based
on the reproductive relations of these organisms. The presence or
absence of a septum (the point of distinction between Mono- and
Polycystide of Stein and Schneider) has in his eyes no deep im-
portance, inasmuch as he has found at Naples, in Typton spongicola,
a Gregarine, which in its early life is a septum-less Monocystidean,
but acquires later not only one, but numerous transverse septa, and
thus presents a colonial or strobila-form which arises by terminal
budding, and whose segments are individually capable of in-
_dependent reproduction. Gabriel finds the attaching apparatus of
* Bollet. Scientif., ii. (1880) pp. 43-50. Cf. Zool. Jahresber. Neapel for
1880, i. p. 127.
+ Prof. O. Biitschli (loc. cit.) remarks on this that this opinion might be ex-
tended with probable accuracy to all fresh-water faunas.
¢ Ber, Versamml. deutsch. Naturforscher u. Aerzte, 1880, pp. 82-3. Cf. Zool.
Jahresber, Neapel for 1880, i. pp. 160-1.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 357
the Polycystides to have no greater importance, it being found
similarly developed in Monocystideew as well. The method of
generation and development exhibits important variations both in
the Mono- and Polycystidex, and, indeed, is repeatedly found to be
identical in members of both the groups. The author at first con-
sidered that the Gregarines should be broken up into two subdivisions,
according as encystation occurs in the course of reproduction or does
not ; these were termed respectively Acystoplasta and Cystoplasta. He
even found that in a Gregarine obtained from Julus sabulosus (and
probably identical with Stenocephalus Juli Schn.), the spore-formation
was completed without encystation, and without alteration of any
kind in the shape of the body. He considers, however, this case not
of sufficient importance to establish the above two subdivisions, and
therefore distinguishes three divisions by the process of development
and spore-formation ; their characters may, however, be stated at the
outset as difficult to understand, owing to the very indistinct pre-
liminary notices in which the results of the author’s developmental
researches are presented. We give the characteristics of these three
divisions as follows in the words of their author :—
“i. Greg. Isoplaste.—The germs of the Gregarine and the series
of the Myxomycetes appear at the same time, and both take their
origin from the differentiated body-mass, but each for itself and in-
dependently one of the other. Cystoplasta represents Myxomycete
forms by plasmodia.
“ii. Greg. Proteroplaste—The body-mass of the Gregarine,
when generatively mature, becomes differentiated into a Myxomycete
plasmodium. The Gregarine germs take their origin from this.
Acystoplasta.
“ii. Greg. Hysteroplaste.—The Gregarine germs first originate
from the differentiated body-mass; the series of the Myxomycetes
proceeds exclusively from certain transformations of the germs of
the Gregarines (ameeboid bodies). Cystoplasta. Myxomycete forms
represented by plasmodia with radiating processes, pigments, cal-
careous corpuscles, and Mycetozoa.”
The Myxomycete forms which produce psorospermiz are regarded
by the author as derived from disintegrated Proteroplasta, but the
“sickle-shaped bodies found in Vertebrata and claimed as Gregarines
by Eimer,” on the other hand, as allied to the Hysteroplasta.
Psorospermie in Man.*—B. Grassi has found in the excrements
of a boy and of a young man during a long period (25 months in
the first case) numerous bodies which after much hesitation he
describes as oval Psorospermiz (Coccidia). They exhibit a number
of variations in size and form; they are sometimes globular, some-
times elliptical; in the first case they generally measure ‘008 mm.
in diameter, but in the latter usually ‘008 to :006 mm.; they have a
distinct, and in the larger individuals a double-contoured test, and
finely granular contents, completely filling the shell and containing
* Rendic. R. Istit. Lombard., iii. (1880) 3 pp. Cf. Zool. Jahresber, Neapel for
1880, i. p. 162.
358 SUMMARY OF CURRENT RESEARCHES RELATING TO
from one to eight roundish nucleoid bodies. The contents may also be
sometimes quite homogeneous or somewhat condensed and retracted
from the test, and in many the protoplasm contained from one to six
semilunar homogeneous glistening bodies, which, however, judging by
the very poor figure given of them, show no special resemblance to
the sickle-shaped bodies of Coccidia. The behaviour of these bodies
towards various reagents and staining substances is also described.
From all this the Coccidian character of these structures seems to be
still doubtful. The two patients exhibited no complaints to which
the presence in them of these parasites might be referred.
Myxosporidia.*—Under this term, which is introduced | by Pro-
fessor O. Biitschli, may be mentioned the so-called parasitic plasmatic
tubes of the pike’s bladder, discovered by Lieberkiihn, and belong-
ing to the so-called Fish-Psorospermiz, so widely distributed in
these animals. According to Gabriel, they have no intimate con-
nections with the Gregarine, as Leydig, and later Lieberkiihn, have
endeavoured to show; the following are the chief reasons which he
advances for thisopinion. These very variously shaped protoplasmic
structures at no period of their life possess an envelope like that of
Gregarine, and they are entirely non-nucleate. Moreover, the surface
of the body frequently developes extensions and radiating processes
of a very peculiar character, appearing now pointed, now finely
fringed, sometimes hair-like and often branched as well, and consist-
ing of protoplasm which is quite transparent, though not entirely
without granules. These stellate processes cannot be directly com-
pared to pseudopodia, for though they are protruded they are not
retracted again. They consist “of what may be called a thread-
drawing substance, which can issue forth with ease but cannot be
again retracted.” A substance of this nature is said to be peculiar
to the protoplasm of Myxomycetes and to certain plasmodia resembling
Myxomycetes, and connected with the development of true Gre-
garines. Real phenomena of motion have not however been observed
by the author in these protoplasmic structures. A further argument
against their Gregarine nature is the presence in them of a yellow
pigment of various shades, pigment of which kind is frequently
found in the Myxomycetes.
To what was known of the formation of the spores of the
true Psorospermiz which occur within the protoplasmic structures,
Gabriel is hardly able to add anything. According to him, the spores
are developed, as already stated by Leydig and Lieberkiihn, in spaces
or vacuoles which are at first unprovided with walls, and later, but
not in all cases, become converted into vesicles by formation of a
wall. The spores are formed within these vacuoles in a manner
which is compared by the author to a process of secretion. Inasmuch
as several spores may develope within a single vacuole, Gabriel terms
the vacuoles “ polysporogenetic centres of development,” and sees in
them a veritable contrast to the “single, monosporogenetic forms of
* Ber. naturw. Sect. Schles. Ges., 1879, pp. 26-33. Cf. Zool, Jahresber.
Neapel for 1880, i. pp. 162-4.
+ Op. cit., p. 162.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 359
development” of the Gregarine germs (Pseudonavicelle). Of the
structure of the spores we learn almost nothing ; in particular, the
remarkable thread-cell-like structure of the so-called polar corpuscles
appears to have quite escaped the author, and he takes no notice at
all of Balbiani’s work on the Psorospermie of fish. He has not
been able to observe any bursting of the spores and emission of an
amceboid body.
On the other hand, he has observed a method of development of
the spores which is carried out inside the bladder, but which he
gives with some reserve. It commences with the solution and absorp-
tion of the containing capsule, but then proceeds in two different
ways. Hither the central protoplasmic part of the spore fuses with
the two polar corpuscles into a single protoplasmic mass, or the parts
remain distinct. In the latter case the spore-contents are said to
break up (in a manner which is not very intelligible) into two pieces,
seldom more. Finally, spore-contents, which have become granular
and vacuolated, are said to develope small, strongly granular plas-
modia, which become the protoplasmic structures first described. The
existence of another process of spore-development appears to the
author to be certain, seeing that at some time or another infection
must take place from outside. As already indicated, the author draws
from his results the conclusion that the structures which we have been
considering cannot be included with the Gregarine, but must be con-
sidered as “spore-forming Myxomycetoid plasmodia,” not, however,
exhibiting the entire characters of the group Myxomycetes. Hence
they are to be regarded as a tribe whose systematic position lies
between the Myxomycetes and Gregarines, a circumstance which
appears to the author to have a most important bearing on the rela-
tions which he represents to exist between these two groups.
Morphology of Protozoa.—L. Maggi * again calls attention to the
differentiation of a mesoplasm between the ecto- and endoplasm, a
fact of deep importance in his view, and first discovered by him
in certain Amcebe and the genus Podostoma. The demarcation of
these three regions in the protoplasm of the body of certain Protozoa
appears to him of especial interest for this reason, that they exhibit an
analogy with the three blastodermic layers of the Metazoa. The
ectoplasm gives rise to the pseudopodia, which effect the relations
with the outer world; on the other hand, the mesoplasm supplies
the contractile vacuole, an organ of circulation, excretion, and exhala-
tion ; lastly, the entoplasm contains the “ entoplasmatic organs,” viz.
the digestive cavity, the nucleus, and nucleolus, the two last being
the organs of reproduction. Thus it is the mesoplasm and entoplasm
which support the vegetative functions of life. Grimm also f has
pronounced in favour of the view of the differentiation of a mesoplasm
and drawn the same parallel with the germinal layers of the Metazoa.
G. Cattaneo ¢ expresses opinions with regard to the morphological
* Bollet. Scientif., i. (1880) pp. 81-3. Cf. Zool. Jahresber. Neapel for 1880, i.
R: Ae sc Obaibeibutioas to the Knowledge of the Simplest Animals,’ 1877, in Russian.
} Atti Soc. Ital. Sci. Nat., xxii. (1880) p. 68 (2 pls.). Cf. Zool. Jahresber,
Neapel, tom. cit., p. 123.
360 SUMMARY OF CURRENT RESEARCHES RELATING TO
structure of plastids precisely similar to those propounded in 1879
by Maggi. In his view the protoplasm and plasson are made up of
numerous simple albuminoid particles, which he agrees with Maggi
in naming plastidules and which represent the simplest morphological
elements. The simplest forms of these plastidules, the so-called pro-
toplastidules, are said to be the granules devoid of independent motion
which are found in organic infusions; with these may perhaps be
ranked as structures of similar morphological value, the free solitary
spherical Bacteria, the Cocci, and Micrococci. If these protoplasti-
dules become differentiated in such a way as to form around them-
selves parts of unequal physiological values, there arise the autoplasti-
dules, among which must be included the simple Microbacteria, such
as Bacterium termo, the Monococci and Monobacteria of Billroth, the
Desmobacteria (Bacillus), and the Spirobacteria (Spirillum). By
colonial growth, on the other hand, the protoplastidules give rise to
symplastidules, among which are placed the social forms of the
Bacteria, as the Diplobacteria, the Strepto-, Glio-, and Petalobacteria,
and also the Amphiasters (Kernspindeln), and stellate figures of cells
in process of division. A combination of plastidules which are not
all developed in the same way forms a plastid.
Differentiation generally takes place in a radiating manner, so
that an outer and an inner mass are formed, differing somewhat from
each other. The simpler forms are in this case the protoplastids,
which include the non-nucleate gymno- and lepo-cytodes, and the
simpler nucleate gymno- and lepo-cellule. By further differentiation
these protoplastids result in autoplastids. The author considers
that the different layers of differentiated substance in a highly
developed autoplastid, viz. ecto-, meso-, entoplasm, nucleus, and
nucleolus, may be compared to so many cytodes concentrically
grouped; and thus an autoplastid of this kind is to be regarded
anatomically (though not genetically) as a colony of cytodes.
The colonies of plastids are described as symplastids. The author
includes among them the Gregarine.
Eozoon Canadense.*—Professors King and Rowney deal with the
question of the organic nature of Hozoon and of simulation of organ-
ized structures generally, their opinion being decidedly in favour of
its mineral origin.
In the first place they state that the “typical nummuline wall”
is a pectinated form of chrysolite, due to modification of that
allomorph of serpentine, where the fibres of the mineral ultimately
become separated acicule with calcareous interpolations. The
“canal system, &c.,” is rather more obscure in its origin. It is
frequently due to the peculiarities of a layer of flocculite (a non-
fibrous allomorph of serpentine), which on undergoing some solvent
or decreting process, is apt to be shaped into irregular configurations.
So likewise the “chamber castes” of the acervuline variety are
identical with the variously lobulated crystalloids characteristic of
* King and Rowney, ‘ An Old Chapter in the Geological Record with a New
Interpretation ; or, Rock Metamorphism and its Resultant Imitation of Organ-
isms.’ 8vo, Van Voorst, 1881. See Geol. Mag., ix. (1882) pp. 231-6.
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 361
Tyree “marble” and similar rocks, due, as the authors believe, to
decretion of the original silicate. As regards the calcitic layer con-
taining the “intermediate skeleton” in typical specimens of Eozoon,
the calcite composing this part is “plainly a replacement pseudo-
morph after serpentine.” This explanation would account for the
alleged cases of “chambers” and “canal system” preserved in
calcite.
BOTANY.
A. GENERAL, including Embryology and Histology of the
Phanerogamia,
Chemical Difference between Dead and Living Protoplasm.—
In the paper by Dr. O. Loew and T. Bokorny, noticed under the
above heading at vol. 1. (1881), pp. 906-7, it should have been stated
in the description of the method employed for producing the reduction
of silver by the protoplasm, that the silver nitrate solution must be
used in an alkaline condition, produced by the addition of ammonia.
Similarly, to obtain reactions with gold chloride and platinum
chloride respectively, the previous addition of caustic soda to the
solution of the salt is necessary.
Dr. Loew describes the preparation of the silver solution as
follows:—(a) Prepare a 1 per cent. solution of nitrate of silver;
(b) mix 18 cc. of a solution of potash (1°33 sp. gr.) with 10 ce. of
caustic ammonia (1°96 sp. gr.), and dilute with water to 100 ce.
Mix 1 ce. of each of (a) and (6) and dilute the 2 cc. to 1 litre imme-
diately before use.
Occurrence of Aldehydes in Chlorophyllaceous Plants.*—J.
Reinke and Kratschmar assert the presence of volatile reducing
substances in all the chlorophyllaceous groups of plants; in alga,
lichens, mosses, ferns, conifers, and angiosperms; while they are
absent from fungi and etiolated seedlings of flowering plants. Their
occurrence appears therefore to be connected with the presence of
chlorophyll, though they may spread to the parts which do not
contain this substance. The authors determined the presence of two
such substances of different reducing powers. From the powerful
reducing properties, it is inferred that these substances belong to
the class of aldehydes; and their power of reducing a neutral
silver solution in the cold appears to identify them with formic
aldehyde. If this should not be confirmed, they may possibly be
identical with acetol or with some other “ ceton-alcohol.”
Organ not hitherto described in the Vegetable Embryo.j—
G. Briosi describes a part of the embryo which he finds in some
plants, and which has hitherto escaped attention. Ifthe exalbuminous
* Berichte deutsch. chem Ges., xiv. (1881) p. 2144. See Bot. Ztg., xl. (1882)
p. 57.
: + G. Briosi, Sopra un organo finora non avvertito di aleuni embrioni vegetali.
15 pp. (8 pls.) Rome, 1882.
Ser. 2.—Vou. II. 2B
362 SUMMARY OF CURRENT RESEARCHES RELATING TO
seed of Eucalyptus globulus is carefully examined, the embryo is seen
to consist of two cotyledons and a radicle without plumule; but the
radicle is found not to be of very simple structure. It is not perfectly
cylindrical, but its lower extremity is somewhat club-shaped. A
longitudinal section shows that its central portion is composed mainly
of the tigellum or hypocotyl, surrounded near its lower extremity by
a kind of collar through which the radicle projects. This collar is
composed entirely of parenchymatous tissue containing no fibro-vascular
bundle, and is completely covered with white hairs. As the seed
germinates it developes to a considerable size, but finally disappears,
leaving not a trace behind. The author believes that it is endowed
with a nutritive function. He has observed it in the embryo of
several genera of Myrtacez, also in Onagrariez: and Lythrariez.
Studies of Protoplasm.*—In a series of papers under this title,
J. Reinke proposes to classify the substances out of which proto-
plasm is composed under the three heads of “constant,” “ variable,”
and “ accessory.”
The author regards the first product of the assimilation of carbonic
acid as probably formic aldehyde, according to the equation CO,;H, —
20 = COH,. From this various polymeric substances are then pro-
duced, as, for example, grape-sugar, 6 CH,O0 = C,H,.0,. The author
distilled leaves of the poplar, willow, and vine with water, and reduced
the distillate by Fehling’s solution and solution of silver nitrate, by
which the presence of an aldehyde-like substance was determined.
The same result was obtained from roots of the willow, and with
leaves which had remained for eight days in the dark.
Composition of the Protoplasm of Athalium septicum.j—In
continuation of previous inyestigations,t J. Reinke and H. Rodewald
give fresh analyses of the protoplasm of Athaliwm septicum. The
plasmodium has, when fresh, an alkaline reaction. A turbid yellowish
fluid, the enchylema, can be obtained by pressure ; it contains albu-
minoids, and can be coagulated at a temperature of 58-64°C. The
fresh plasmodium contains 71°6 per cent. of water ; the following is
an analysis of the ash :—
Per cent.
Carbonictacid yi... was ase ee ole ee OO LO
Phosphoriciacia’..2” #5." Vi Foe ee 649
Sulphuric acid 5 i.) 05 Wel sie cate ce ORAS
Chiorine st 2st tee ine toe ee te oe asenOeen
Sesquioxidejof iron. das i ich as.) Gin ae AO
Tinie fee Ley dc. Viegas epee Tees ce Oe
Oxide ofmarnesium=, (% 2 es) acer a OSM
Potassa Behe ace HANS eats) Uae hbase! mera la tb De:
Sodadicrs ey i: dae Mes eS ee) bo ree
99°92
Extraction of the air-dried substance by ether yields from 5-36
to 8:13 per cent. of extract, which saponifies in alcoholic solution, and
* Unters. aus dem bot. Lab. Gottingen, 1881, pp. 74-184, 187-202.
+ Ibid., pp. 1-75. See Bot. Centralbl., viii. (1881) p. 292.
‘t See this Journal, i, (1881) pp. 283, 918.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 363
yields about 21 per cent. of paracholesterin. The volatile fatty acids
found were propionic, butyric, caprionic, and probably caprinic acid,
the non-volatile fatty acids, stearic, palmitic, and oleic acids.
The spores contain a larger quantity of asparagin than the proto-
plasm. The presence of acetic and oxalic acids was certainly, that of
lactic acid probably, determined. In perfectly fresh protoplasm,
Hoppe-Seyler’s method determined the presence of myosin and
vitellin; in the glycerin-extract was a ferment (pepsin) with the
property of dissolving albumen.
Properties of the Protoplasm in Urtica urens.*—F. Kallen
has investigated the phenomena displayed by the protoplasm of the
stinging-nettle, in the merismatic cells, the medullary cells, the
epidermal cells, the hairs, the glandular hairs, the stinging hairs, the
cortical parenchymatous cells, the bast-fibres, the cells of the soft
bast, the cambium cells, the wood-vessels, and the prosenchymatous
cells. The following are the general results arrived at.
In all the cells the nucleus is densest and largest in comparison
to the size of the cell in the youngest stage. In older stages of the
parenchymatous cells there is frequent fragmentation ; this occurs in
the pith, the cortex, and the unthickened wood-parenchyma-cells.
The finely punctated protoplasm exhibits at all stages a coarsely reti-
culate structure, as in the medullary cells; but the interstices are
covered by a hyaline layer of protoplasm, so that the protoplasmic
utricle is nowhere interrupted. The nucleus does not usually dis-
appear before the protoplasm ; in the sieve-tubes only does this take
place; while in older stages of the bast-fibres, the nucleus is partially
absorbed. In the xylem-vessels the nucleus and protoplasm never
disappear. Crystalloids were in a few cases found in the nuclei of
the hairs. The multinucleated bast-fibres contain latex. The nuclei
of the bast-fibres multiply by fragmentation, not, as Treub supposes,
by division.
Fertilization of Salvia splendens.t—W. Trelease describes the
“ ornithophilous” structure of this Brazilian species, the structure being
especially adapted for fertilization by humming-birds. It is proter-
androus, and there is no arrangement to facilitate fertilization by
either day or night-flying insects.
Reproductive Organs of Loranthacee.{—M. Treub has investi-
gated the development and structure of the sexual organs in this
natural order in the case of Loranthus spherocarpus. The rudimentary
carpels enclose a small cavity, in the middle of which rises a hemi-
spherical central papilla, an elongation of the axis. This papilla is
so connected with the carpels that only three or four canals remain
open, and these also soon disappear. Before this complete union is
effected, there can be detected in each free lobe of the central papilla
hypodermal cells of larger size, which soon assume a nearly vertical
+ Flora, Ixv. (1882) pp. 65-80, 81-92, 97-105 (1 pl.).
+ Amer. Natural., xv. (1881) pp. 265-9.
{ Ann. Jard. bot. Buitenzorg (Java), ii. (1881) pp. 54-76 (8 pls.). See Bot,
Ztg., xl. 1882) p. 59. ; 9
4B
364 SUMMARY OF CURRENT RESEARCHES RELATING TO
position, and divide, by transverse septa, into three superposed cells.
Of the four or five rows of cells thus formed, the uppermost daughter-
cell of one only developes, and becomes the embryo-sac; all the rest
are resorbed, including the two belonging to the same row. Since
each of the originally free lobes from the central papilla forms an
embryo-sac, and the number of these lobes corresponds to that of the
carpels, the number of embryo-sacs in the ovary also corresponds to
that of the carpels. Round the embryo-sac is formed, partly out of
the previous epidermal cells of the central papilla, a sheath of amy-
laceous cells, which is prolonged upwards into a similar row, while
in the lower part of the ovary is developed a sheath of collen-
chymatous tissue open above. ‘lhe embryo-sacs elongate to an extra-
ordinary extent both upwards and downwards, following upwards the
row of amylaceous cells till they reach the base of the style, and there
somewhat expand; while they extend downwards to the base of the
collenchymatous sheath. Their nucleus now divides; one of the
daughter-nuclei moves into the upper expanded portion of the sac
and again divides.
The first wall in the fertilized germinal cell is longitudinal,
followed in each half by several transverse septa. The lower cells
of this suspensor divide further, while the upper ones grow to an
extraordinary length, and force the lower apex of the embryo between
the first endosperm-cells, which have at the same time been formed
in the lower part of the embryo-sac; the embryo being thus finally
attached to the end of the double thread which constitutes the sus-
pensor, and which is rolled up between the embryo and the endo-
sperm. 'The endosperm cells now increase rapidly in number in its
lower and peripheral parts, thus crushing the suspensor, which finally
entirely disappears. The radicular end of the embryo then penetrates
into the endosperm and consumes it; and the embryo becomes com-
pletely enclosed in the collenchymatous sheath; rising up into it,
partly in consequence of the pressure of the lower part of the endo-
sperm.
The central papilla formed in the centre of the ovarian cavity was
regarded by Griffith as a placenta with rudimentary ovules; by Hof-
meister as an orthotropous nucleus without integuments, in which
several embryo-sacs are formed, and the chalaza of which is repre-
sented by the collenchymatous sheath. Treub supports the former
view, and considers the axial portion of the papilla to be of the
nature of a placenta, its three or four lobes being rudimentary
ovules; a view confirmed by the somewhat similar structure presented
by the Santalacee. Griffith thought that the single embryo was the
result of the coalescence of several ; Treub is unable to confirm this ;
but, on the other hand, found frequent evidence of the abortion of
embryos, one only of which reaches maturity.
Structure and Mode of Formation of Spermatozoids,*—
K. Zacharias has investigated the behaviour with different reagents of
the various constituents of spermatozoids, chiefly those of Nitella
* Bot. Ztg., xxxix. (1881) pp. 827-38, 846-52.
ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 365
syncarpa and Chara aspera. The spermatozoid he regards as com-
posed of three parts—the spiral band, the paler terminal portion or
vesicle, and the cilia.
A solution of pepsin does not dissolve the spiral band ; it becomes,
on the contrary, more distinct and strongly refractive, either retaining
altogether its original form, or becoming more or less short and
thick; the separate coils sometimes coalesce into a single homoge-
neous refractive lump. The cilia are almost completely dissolved,
while the posterior vesicle swells up, and finally again contracts,
430 SUMMARY OF CURRENT RESEARCHES RELATING TO
hard day’s work. Specimens as large as the central hemisphere of
a rabbit can be stained and imbedded whole.
I append my notes on the spinal cord of a frog, showing the
times used in the various processes :—
Cord put into 3 per cent. nitric acid, 2 hours.
Seventy per cent. alcohol, 6 hours.
Stained in hematoxylin, 4 hours.
Seventy per cent. alcohol, overnight.
Ninety-five per cent. alcohol, 24 hours.
Oil of cloves, 24 hours (did not wish to imbed till next day) ;
then,
Turpentine, stir half-an-hour.
Turpentine and paraffin, 1 hour.
Paraffin, 1 hour.
It should be remembered that these cords imbed easily.
One caution further; select paraffin, if possible, which is bluish-
transparent, and which rings slightly when struck. The white
opaque sort is by no means as good. Any addition of paraffin-oil,
turpentine, &c., to soften the paraffin, renders it granular and brittle,
and is decidedly injurious to its cutting qualities.”
Williams’ Freezing Microtome adapted for Use with Ether.*—
The original form of this Microtome was described and figured at
pp. 697-9 of vol. i. (1881). It subsequently occurred to Mr. J. W.
Groves that it would be an improvement if it were adapted for the use
of ether as a freezing agent instead of ice and salt. Mr. J. Swift
* Journ. Quek. Micr. Club, vi. (1881) pp. 293-5 (2 figs.).
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 431
accordingly worked out the details of the adaptation which is shown
in Fig. 83. D represents the wooden bowl of the original form
altered to hold the ether freezing apparatus. A and B are the razor
frame and bowl-cover with the glass-plate top upon which the former
is moved. The central brass cylinder, instead of being solid, is
hollow, so that the ether spray may play up the inside and impinge
upon the lower surface of the brass-plate I, upon the upper surface of
which the material to be frozenis placed. In the figure, the hollowed
cylinder is seen to open below into the ether-containing chamber,
into the lower part of which also opens a horizontal tube, which turns
up at right angles and ends in a funnel-shaped extremity G, over
which screws a cap.
In the centre of the bottom of this chamber is a circular aperture
closed by a piece of brass tubing, which passes up vertically to end
in a cone with a very small aperture, and having another small hole
in it towards the bottom. The lower end of this tube is plugged, and
through the plug E passes vertically a very fine tube, which is con-
tinuous below with the tube from the apparatus for pumping in
air. ‘This consists of an indiarubber pump F, connected by a short
piece of tubing with a slightly distensible ball covered with
netting, and from the opposite side of which a piece of indiarubber
tubing passes on towards E. Inthe side of the large hollow cylinder
of the machine is inserted a small tube connected with a length of
pipe H for the escape of the spray after use.
The method of freezing is as follows:—After the material has
been partially hardened, and the hardening agent removed, place it
on the brass plate I with a little gum mucilage;* then unscrew the
cap G, fill the chamber with ether, replace the cap, and commence
pumping by pressing the ball F vigorously and rapidly in the palm
of the hand. Air will thus be pumped into the net-covered ball, from
which it will issue in a continuous jet along the indiarubber tube,
up the small tube, through the plug H, and again through the hole at
the apex of the conical-ended vertical tube, to pass straight up against
the under surface of the plate I. The rush of air thus produced
causes pressure on the surface of the ether, and also tends to produce
suction at the space between the small central tube and the one
which has the conical extremity, so that the ether passes through the
hole in the side of the latter tube, rises in the space between the two
tubes, and is forced as a jet of spray through the hole in the cone,
and so on to the under surface of the plate I. This is roughened in
the form of teeth for the purpose of presenting a large area to
be acted upon, and also to facilitate drainage. A great deal of the
ether drops down into the chamber, and is used again, but a little
passes out mingled with the air in such a finely atomized condition
that it seems impossible to collect it, and it is therefore conveyed
along the tube H to the external air.
The advantages of the new form are that all mess with ice and
salt is avoided, that ether can always be kept at hand, and that
inhalation of the vapour is limited to the short period during which
* If the material is quite fresh the mucilage may be dispensed with,
432 SUMMARY OF CURRENT RESEARCHES RELATING TO
the chamber is being filled. The labour of pumping may be reduced
by placing the ball-pump between two pieces of wood hinged like
lemon-squeezers. Material has been frozen in a room at 96 F. using
ether of +730 sp. gr.
Swift and Son’s Improved Microtome.—In the microtome just
described the sections are cut and their thickness regulated by the
gradual descent of the knife towards the tissue to be operated upon.
In order to reverse this process and provide a machine in which the
tissue shall ascend towards the knife—as is the case in the ordinary
form of section-cutters—Messrs. Swift and Son have brought out
their new microtome, a drawing of which is given in Fig. 84, and which
Fic. 84.
is described as follows by Dr. S. Marsh in the new edition of his
useful little work on section-cutting.
“The instrument consists of a massive iron upright, terminating
at its lower extremity in a clamping arrangement, by which it may be
securely fastened to the table. From the top of the upright two highly
polished iron bars, lying parallel to each other, run horizontally for-
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 433
wards. These bars correspond to the cutting plate in the usual form
of microtome, and upon them, as will be seen at A in the drawing, a
flat brass frame carrying a knife is made to glide. The knife is kept
firmly in position on this framework by means of the binding screw OC,
the end of which, terminating in a square clamp, presses against the
back of the blade. ‘The face of this clamp is grooved in different
directions in such a manner that, according as the back of the blade is
received into one or another of these grooves it is pushed from or
drawn towards the level of the framework, thus affording a means by
which the edge of the knife may be set at varying angles to the tissue
to be cut. In front of the iron stand will be seen an angular upright
pillar carrying in front of it a short length of sprung brass tube B,
into which any of the apparatus presently to be described may be
firmly fixed by a clamping screw. By means of a micrometer-screw
E fixed at the base of the angular pillar, the sprung tube, and of
course whatever it may carry, can be acted upon so as to raise or
lower it at pleasure. The amount of movement thus effected is
registered by the milled head of the screw, for which purpose three
concentric circles have been drawn upon its face, each of which is
so graduated that, as the face rotates from mark to mark, the distance
traversed by the screw, and which of course determines the thickness
of the section, will in the case of the outer circle be 1000th, in that
of the middle 500th, and in the inner one 400th of an inch. The
index by which these measurements are recorded consists of a spring
catch so fitted that, as the milled head rotates, it drops into the
divisions of the circles, into either of which it can be shifted at
pleasure, or if desired can be thrown out of gear altogether. When
it is intended to use the microtome for freezing with ether, the
chamber provided for that purpose, and which in the engraving is
shown in position, must be employed. This chamber is like the one
already described when speaking of the Groves-Williams microtome,
and consists of a reservoir for containing the ether and an upright
cylinder leading from it, and terminating in a flat plate, upon which
the object to be frozen lies. 'To use the machine, remove the cup D,
fill the chamber with ether, then fix the cylinder in the clamp B,
when the bellows F being worked the ether will project through the
tubes in the interior of the chamber (which were described at p. 431),
upon the plate holding the tissue, with the effect of speedily freezing
it. When, under the action of the micrometer-screw, the object to
be cut has moved upwards between the cutting bars sufficiently high
for the purpose, sections are to be obtained by simply pushing the
frame carrying the knife obliquely across the bars and through the
tissue. For freezing purposes common methylated ether of a density
of -720 answers perfectly well. In winter when ice is plentiful, and
where only a very small piece of tissue requires to be frozen, the
freezing may be effected without the employment of ether. For this
purpose it will be necessary to use Dr. Pritchard’s solid freezer,
Fig. 85. As will be seen, it consists of a solid metal block, having
its upper surface, upon which the tissue to be frozen lies, roughened
so as to prevent the specimen from slipping during section. For
434 SUMMARY OF CURRENT RESEARCHES RELATING TO
use, the block and tissue are frozen by being immersed in powdered
ice and salt, then the block is secured in the clamp B, and sections
cut in the manner just described. The microtome, though essentially
a freezing one, may however be employed for cutting objects im-
bedded in paraffin. For carrying out this, the box shown in Fig. 86
has been provided. The tissue is to be imbedded in this box, and
when the paraffin has become quite cold, the box must be secured
in the clamp B and the tissue sectionized.
“Yet another piece of apparatus belongs to this machine. It is
called an adjustable vice, and is shown in Fig. 87. It is the most
useful accessory, and there has long been a want felt for something
Fic. 85.
of its kind. It consists of a cylinder carrying at its upper end the
two jaws of a vice. One of the jaws is fixed, whilst the other, being
movable, may be made to recede from or approach to its fellow by
means of the screw, so that hard substances of different kinds and
various sizes may be securely fixed and held between the jaws, when,
the cylinder being inserted in the clamp B, sections may be readily
obtained. To the really working microscopist, this little appliance
will be found of infinite value in a thousand directions. The uses
of it are so obvious that no words will be wasted in describing them.”
Though in this form, as in the others, the section knife, when
in use, is mounted on a frame, no absolute necessity for its adoption
exists, for the construction of the microtome permits of the use of
an unmounted knife as readily as one mounted on a frame. The
frame arranged has some advantages, particularly in retaining the
keenness of the blade for a considerable period (coming into contact
with nothing but the tissue) and in the confidence which it gives to
the inexperienced operator. On the other hand, it renders the dis-
engagement of the sections from the knife both a tedious and unsafe
process, and Dr. Marsh is strongly of opinion, as the result of a very
considerable amount of practical work, that in the hands of those who
by careful practice have taught themselves how to use it, a simple
unguarded knife is to be preferred to any mechanical arrangement
whatever.
Bausch and Lomb’s Standard Self Centering Turntable—We
were unable to give at p. 284 any description of this turntable, but
the following has since been supplied by Mr, E. Bausch.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 435
The self-centering arrangement of the turntable is easily manipu-
lated. The jaws are compressed by springs, and bear gently against
the slide, so that, although it is firmly held, there is no danger of
mutilating its corners or breaking it. One-sixth of a revolution of
the milled ring is sufficient to open the jaws to their full extent, and
as this is easily done with one hand, the other is free to place the
slides. The hand-rest is detachable from the turntable. It has on
its lower surface an adjusting screw for varying the distance from the
revolving disk.
For refinishing old slides, or others on which the object has not
been well centered, a detachable pair of spring clips are provided.
Concentric circles up to one inch diameter are turned on the
disk.
Crystallised Fruit Salt.*—Mr. G. J. Wightman says that Eno’s
fruit salt, when crystallised, makes a magnificent polariscope object.
The mode of preparation is as follows: In a small test tube, say
3 X 2 inches, dissolve as much of the salt as would rest on a six-
pence, by adding distilled water to the depth of an inch. With the
end of a glass rod spread a few drops over an ordinary glass slip,
and in a few minutes crystallisation will take place. The slide (with
selenite) will be seen to be covered with numerous beautiful forma-
tions, each somewhat resembling a Maltese cross made up of bril-
liantly-coloured needle-like crystals. If it is held over the flame of
a lamp as soon as the solution is placed on (so as to hasten crystallisa-
tion), the colours will be the more splendid without selenite. Other
beautiful effects may be produced by the addition of a few drops of
alcohol to the test tube. The slides, as soon as dry, may be mounted
in Canada balsam.
AL.eEnN, F. J.—Cleaning Gizzards.
[Feed the insects on honey, syrup, or treacle, before killing them.]
Journ. Post. Micr, Soc., 1. (1882) pp. 48-9.
ARNOLD, J. W. S.—Microscopical Laboratories.
(Comments, &c., on the previous articles on the same subject—also as to
the superiority of small instruments. ]
Amer. Mon. Micr. Journ., III. (1882) pp. 69-70, 75.
BAGuvT, Col.—Mounting Starches.
[Not in balsam, but dry or in glycerine jelly, and viewed as opaque
objects. ]
Journ. Post. Micr. Soc., I. (1882) pp. 49-50.
Birce, E. A.—On a Convenient Metliod of Imbedding.
[Supr a, p. 428. ]
Amer. Mon. Micr, Journ., II. (1882) pp. 73-5,
Blood Stains on Steel.
[Dr. M. C. White recognized and measured by means of the vertical
illuminator and 1-ineh objective, blood-corpuscles upon a steel instru-
ment that had been exposed during two winters in the woods. ]
Amer. Natural., XVI. (1882) p. 347.
Bowmay, F.. H.—See Cotton infra.
Cuaton, Listes de préparations histologiques et botaniques de M. (List of
histological and botanical preparations of M. Chalon.)
Bull, Soc, Belg. Micr., VII. (1882) pp. liv.-vii.
* Sci.-Gossip, 1882, p. 64.
436 SUMMARY OF CURRENT RESEARCHES RELATING TO
CuHEESEMAN, E. L.—Home-made Apparatus for Collecting.
[ Bottle-holder to be attached to a stick made of a narrow strip of sheet
brass, and an ordinary gimlet-pointed wood-screw with the head
flattened. ]
Amer. Mon, Micr, Journ., III. (1882) p. 61 (1 fig.).
Coal-sections, Cutting.
{Notes by A. Smith, E. Holmes, and W. D. Smith, on Mr. Kitton’s note
infra—agreeing as to the failure of the carbonate of potash proce-s. ]
Sci.-Gossip, 1882, pp. 113-4.
Cotton Fibre, Structure of.
[Review of Dr. F. H. Bowman’s book, ante, p. 119, with additional
remarks. |
Amer. Natural., XVI. (1882) pp. 431-2.
Dyck, F. C. van.—Apparent Motions of Objects.
Amer, Mon. Micr. Journ., ILI. (1882) pp. 72-3.
Excocr, C.—How to Prepare Foraminifera.
[For recent Foraminifera from sand, such as shore-gatherings, dredgings,
&e.—1. Well wash in fresh water to remove the salt. 2. Dry perfectly,
and allow to get cold. 3. Sift (sieve No. 50 or 60), 4. Float the fine
material in cold fresh water. 5. Dry the floatings. Perhaps it may
also be found needful to—6. Boil the floatings in liquor-potusse, B. P.
7. Wash away every trace of potash. 8. Dry. 9. Re-float in a beaker.
10. Dry again ready for mounting. ]
Journ. Post. Micr. Soc., 1. (1882) pp. 25-9.
Enock, F.—Metal Caps for Glycerine Mounts.
Journ. Quek. Micr, Club, I. (1881) p. 40.
FLEemine, J.—Mounting Volvox Globator in Glycerine Jelly.
[After a month’s time the Volvor mounted in glycerine jelly, boiling, &e.
in the usual way, ‘‘is perfect in form and colour, and the success of
the attempt goes to prove that this Alga can be treated like any
other, and may be boiled and pressed without the destruction of its
shape.”
ie North. Microscopist, If. (1882) p. 129.
GorrscHav, —.—Mikrotomklammer fiir Keil- und plan-parallele Schnitte.
(Microtome-clamp for wedge-shaped and plane sections.)
SB. Phys.-Med. Gesell, Wirzbirg, 1881, pp. 123-5.
Grarr, T. 8. U. pze.—Resolution of Fasoldt’s 18-band plate, and last band of
19-band plate.
[ Supra, p. 416.]
Bausch § Lomb Optical Co.’s Supplement to Catalogue, Feb, 1882, p. 6.
GREEN, J. H.—Cleaning and Mounting Gizzards. P
[Kill the insect in spirit and leave for 3 or 4 weeks to harden. On
opening the gizzard the loose particl:s of food or dirt can be washed
out by Mr. Nicholson’s (infra) or other plans——Mount in slightly
acidulated glycerine (not balsam) in a cell of gold-size.]
Journ. Post. Micr, Soc., 1. (1882) p. 49.
Groves, J. W.—Improved Ether Freezing Microtome.
[osupra, p. 432.]
Journ. Quek, Mier. Club, I. (1882) pp. 43-4.
Marsh’s Microscopical Section-cutting, 2nd ed. 1882, pp. 60-8 (1 fig.).
Harcu, H.—Microscopical Laboratories.
[Remarks on article by Dr. J. W. Crumbaugh, ante, p. 287, who, he
considers, desires to surround the student with too much and too
expensive paraphernalia, discouraging him at the start.]
Amer. Mon, Micr, Journ., III. (1882) pp. 51-2.
Hircucock, R.—Ruled Bands.
[Supra, p. 415.]
Amer, Mon. Mier, Journ., IIL. (1882) pp. 52-3.
4 os Illumination and Resolution.
[Directions for resolving Amphipleura pellucida—in many cases of failure
the fault is entirely in the illumination. ]
Amer. Mon, Micr, Journ., IIL. (1882) pp, 53-4.
ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 457
Hircucock, R.—Mounting.
[General remarks as to mounting for “ busy professional men who value
every moment of their time and who, not having learned any simple
process for mounting, are discouraged from attempting it by the
multiplicity of processes and cements given in the books.” ]
Amer. Mon. Micr. Journ., IL. (1882) pp. 55-6.
5s 3 Collecting.
[Note on objects to be found in March—May, and suggestions for the
novice in collecting. |
Amer. Mon. Micr. Journ., U1. (1882) p. 77.
Juema, J—On the Origin and Growth of the Eggs and Egg-strings in
Vephelis, with some obseryations on the “Spiral Asters.”
[Contains methods of investigation for (1) genital organs in fresh condi-
tion, (2) sections of entire leech, (3) hardening ovaries and egg-
strings, (4) section-cutting, (5) surface views of the ovary-wall, (6)
examination of early changes in mature eggs. ]
Quart. Journ. Mier. Sci., XXII. (1882) pp. 189-211 ( pls.).
Kirron, F.—Cutting Sections of Coal.
[Describes his failures with the process given under “Coal” in the
‘Micrographie Dictionary’ (maceration in carbonate of potash), and
inquiring for the experience of others.]
Sci.-Gossip, 1882, p. 89.
Korscue_t, E.—EHine neue Methode zur Conservirung yon Infusorien und
Ameceben. (A New Method for Preserving Infusoria and Amcebe.)
Zool. Anzeig., V. (1882) pp. 217-9.
Kunz, —.—Cinnamon Oil for the Examination of Rough Minerals.
[By applying a few drops of oil to the surface of a transparent mineral,
the interior can be examined for inclusions, flaws, &c., without grinding
the surface flat. Sand can thus be examined for inclusions under the
Microscope. ]
Amer, Mon. Micr. Journ., IT. (1882) p. 59.
Liste, T.—Glycerine-jelly Mounts.
[Remedy for failures caused by imperfect removal of superfluous jelly :—
Apply a mixture of whiting or chalk and water about the consistency
of cream, to absorb the jelly; dry and break off carefully.]
Journ. Post. Mier. Soc., I. (1882) p. 49.
MarcuaL, E.—Préparations microscopiques destinées a Jl’enseignement.
(Microscopical Preparations for Teaching)—contd.
[B. Compound Organs, Stems, Roots, Leaves, Flowers ; C. Cryptogams—
‘Ferns, Mosses, Lichens, Algz, Fungi.]
Bull. Soc. Belg. Micr., VII. (1882) pp. xlvi.—liv.
Marsu, S.—Microscopical Section-cutting. A practical Guide to the pre-
paration and mounting of sections for the Microscope, special prominence beiag
given to the subject of animal sections. 2nd ed. 8vo, London, 1882, xi. and 156
pp. and 17 figs.
Marruews, J.—See Michael, A. D.
Micuart, A. D., and Marrsews, J.—Polarized Light as an addition to
Staining for Vegetable and Animal Substances.
{Supra, p. 426.]
Journ. Quek, Micr. Club, I. (1882) pp. 49-51.
Nicuotson, A.—Cleaning Gizzards.
[Open and place in water for a day or two, and clean by agitating the
water strongly by blowing through a pipette. ]
Journ. Post. Micr. Soc., I. (1882) p. 49.
Nosert’s Ruling Machine.
[A query as to its construction, &c., by Akakia. }
Engl. Mech., XX XY. (1882) p. 227.
NorD.incer’s Wood Sections.
{Transverse sections of the most important and most common trees. ]
North. Microscopist, II. (1882) p. 130.
438 SUMMARY OF CURRENT RESEARCHES, ETC.
OLLARD, J. A.—Micro- Fungi.
(Short note as to mounting. ]
Engl. Mech., XX XV. (1882) p. 201.
PritzNer, W.—Nervenendigungen in Epithel (Nerve-endings in Epithelium).
(Contains description of methods, pp. 731-2.]
Morphol. Jahr., VIL. (1882) pp. 726-45 (1 pl.).
Pigeon-post Films.
(Offer of gelatine films used for transmission of news by pigeon post
during the siege of Paris.]
Amer, Natural., XVI. (1882) p. 347.
Pocgitincton, H.—The use of Staining Fluids in Vegetable Microscopy.
[Résumé of various processes. ]
Engl. Mech., XX XV. (1882) pp. 210-2.
Scuréper’s Microtome for Cutting Sections of Diatoms, &e.
[A query as to its practical success, by Akakia. ]
Engl. Mech., XX XV. (1882) p. 227.
Snow Crystals.
(Query by T. Pearson as to the best way to examine them, “as they
melt even in a room where there is no fire.]
Sci.-Gossip, 1882, p. 114.
Sorpy, H. C.—Preparation of Transparent Sections of Rocks and Minerals.
(In part.)
es [Account of the method he originally adopted for rock sections when
“ everything had to be learnt, and there were then none of the facilities
you have now.’’}
North. Microscopist, II. (1882) pp. 101-6.
TrEasDALE, W.—G. Chantrill’s Method of keeping objects alive for many
months.
[A number of zine shelves kept under a bell-glass, the requisite supply
of moisture being provided by a quantity of thick felt kept constantly
saturated.]
Journ, Quek. Micr, Club, I. (1882) p. 41.
UnveErui11, H. M. J.—Cleaning Gizzards.
(Soaking in potash for a day.}
Journ. Post. Micr. Soc., I. (1882) p. 48.
oe == —Glycerine-Jelly Mounts.
[Washing superfluous jelly off with a tooth-brush under water is a
simpler method than Lisle’s (supra). Varnish must be applied within
lialf an hour after cleaning or the jelly shrinks from the edge.
Journ. Post. Micr. Soc., I. (1882) p. 49.
“ Votvox.’’— Microscopy.
{Examining circulation of blood in a tadpole’s tail. Take a hollow
slide, or make a little trough by cementing four little strips of glass
on a 3 x 1 slip so as to make a shallow cell. After placing the
tadpole on its side in the cell and covering with water, drop a very
small quantity of chloroform over its head. There is then “no pain
to the tadpole nor risk of bruising it as when it is put under pres-
sure, and should too much chloroform have been given it could not
die in an easier way.”]
Engl, Mech., XXXV. (1882) pp. 216-7.
Wuite, T. C.—On the Injection of Specimens for Microscopie Examination.
{Describes the process of making transparent injections of a small
Mammal with cold injection fluid (Beale’s blue fluid), mounting in
weak glycerine and camphor- water, and not in balsam or dammar,
which would show nothing beyond the injected vessels, all the sub-
structure which bears an intimate relation to the vascular arrange-
ment being obliterated. Criticism of Dr. Carpenter’s recommendation
of injections by professional mounters. }
Journ. Quek. Micr, Club, I. (1882) pp. 15-9.
Wixton’s (E. W.) Pond Life.
[Intended supply of living objects.)
Sci.-Gossip, 1882, p. 90.
PROCEEDINGS OF THE SOCIETY.
Mertine or 127TH Aprin, 1882, ar Krna’s Cotiece, Stranp, W.C.,
Tue Prestpent (Proressor P. Martin Dunoan, F.R.S) mw
THE CHAIR.
The Minutes of the Meeting of 8th March last were read and
confirmed, and were signed by the President.
The List of Donations (exclusive of exchanges and reprints)
received since the last meeting was submitted, and the thanks of the
Society given to the donors.
From
Loew, O., and Bokorny, T.—Die Chemische Kraftquelle im
lebenden Protoplasma. viii. and 78 pp. (1 plate). 8vo,
Witen@ ein, Wee: oo, co ba do ee oe oes oo be. PU OL eye
Micrographic Dictionary. 4thed. Parts 8,9,and10 .. .. Mr. Van Voorst.
Postal Microscopical Society—Journal, vol. i.No.1.. .. .. The Society.
Mr. M. M. Hartog (of Owens College) described some specimens
which he exhibited. One of these was a living larva of Apus cancri-
formis, the largest of the water fleas, the specimen shown having
been bred this spring from some mud received from Germany. The
other exhibits were a series of sections of Entomostraca which had
been prepared for histological study. The specimens were killed by
adding a few drops of osmic acid to the water in which they were
placed, and as soon as they fell to the bottom they were sometimes
removed to spirit direct; this plan had its advantage inasmuch as
any mutilation was thereby avoided, but on the other hand by opening
them in the osmic acid a certain amount of maceration was avoidable,
which might in the former case prove to be detrimental to the
histological structure. They were first transferred to 30 per cent.
spirit, and then to 50 per cent., after which they were placed in
cochineal solution in 70 per cent. alcohol and washed repeatedly in
clean 70 per cent. alcohol until they gave up no more colour. After-
wards they were placed in 90 per cent., and then in absolute alcohol.
They were next treated after Giesbrecht’s method, with a greasy
medium, and for this purpose whilst they were in the absolute
alcohol a small quantity of oil of cloves was poured in, this sank to
the bottom of the tube, and the Entomostraca would then lie not at
the bottom but just between the alcohol and the oil of cloves, which
gradually replaces the alcohol. In this way, with specimens which
had been unopened, he had obtained preparations in which there had
been absolutely no shrinkage of the protoplasm. Most of the oil of
cloves was poured away and the specimens having been imbedded in
a mixture of spermaceti and castor oil, the sections were cut in the
usual way. It would be noticed that the sections were arranged in
series on the slide. By this means of preparation he had been able
to make out some important points. ‘The specimens exhibited
440 PROCEEDINGS OF THE SOCIETY.
(sagittal sections) the entire organs of the body, the nervous cord
could be well seen, as could also the gullet with its muscles. A
rough sketch was made on the slate to illustrate the chief points of
interest.
Mr. Beck thought the remarks of Mr. Hartog were exceedingly
interesting, for if they were ever really to understand these structures
it must be by means of sections. He was glad to have heard the very
practical remarks which had been made, and hoped they would be
the means of inducing others to practise the process, feeling sure
that such a study would elucidate many points which were now
involved in mystery.
Mr. Stewart inquired whether in cutting the sections a microtome
was used, or whether they were cut by hand. It also occurred to him
that this process might be very useful in the preparation of sections
of many of the soft-bodied creatures such as the mites or the Arach-
nida, for it was very difficult to make out many parts of their anatomy
by any process of dissection.
Mr. Hartog, in reply, said that in all cases where sections had to
be cut in series a microtome was necessarily used in order to secure
perfect regularity of thickness. Zeiss’s microtome was the one he had
employed, using oil to moisten the razor. He agreed that the process
would be very useful in the case of mites and spiders, but he thought
it well to remark that picric acid—so much in fayour for some
purposes—should be avoided, as it penetrated too freely and caused
the soft tissues to shrink from the chitinous body-wall.
Mr. Crisp called attention to two Microscopes which he had
brought for exhibition ; one of these, made in Dundee—which it had
been proposed to call the “ Jumbo” Microscope—stood 4 feet high,
with a tube 4 inches in diameter, and weighed about 13 cwt. It must
have been made about 50 years ago. The other (the “ Midget”)
made by Mr. 8. Holmes—shown by way of contrast—was completely
finished for use, its entire height being only 3 inches, and its weight
only a few ounces. Six of such Microscopes could be enclosed in
the eye-piece of the larger one. He also exhibited the “ Acme”
Class Microscope (see p. 251), and Browning’s Portable Microscope
(see p. 252).
Mr. Beck examined the large instrument and made some remarks
as to the peculiarity of its construction.
Dr. Loew’s note as to the chemical difference between living and
dead protoplasm was read, and a photograph exhibited illustrating
his and Bokorny’s statement as to the different reaction of dead and
living protoplasm on silver salts (see I. (1881) pp. 906-7).
Mr. A. W. Bennett said that the photograph represented two fila-
ments of Spirogyra: nitida, One of these had been subjected in a
living condition to the silver reagent, and the reducing effect of the
living protoplasm had converted the cell-contents into a black opaque
mass. The other filament had been killed by a 1 per cent. solution
of citric acid before treatment with the silver solution. In this case
PROCEEDINGS OF THE SOCIETY. 44]
no reduction and consequent blackening is exhibited, the spiral
arrangement of the chlorophyll-bands being still perfectly distinct.
Mr. Stewart said he did not see that they had any actual proof
that the protoplasm in the one case was dead and in the other living,
especially when it was borne in mind that the way in which it was
killed was by means of citric acid, a small residual quantity of which
he thought might have some effect upon the result.
Mr. Bennett said it was clear that they wanted more particulars
before coming to a definite conclusion, though it was naturally to be
supposed that all acid had been remoyed before the tests were
applied.
Mr. Hartog referred to the silver staining processes recently
described in the Journal.
Mr. Stewart said if they wanted to make silver staining a test in the
case of the tissues of living animals it would not always be found an
easy thing to do. In cases of operations they could probably get living
tissues, but there were many parts which it would be very desirable to
test with, which could not be obtained until after twenty-four hours
from time of death, and yet he thought that in such cases the outlines
of a cell were as perfectly rendered as if they were living. He was
afraid that unless the citric acid were entirely eliminated, it would
probably exercise an important influence on the results.
Dr. Matthews felt sure that such would be the case, for it was
well known that in photography the developing fluids had been
acidified—and this especially by citric acid—for the purpose of
retarding the reduction of the silver salt, so that the results where
acid had been concerned would be very suspicious. The use of
alkaline instead of acid preparations was the secret of the modern
rapid processes of photographic development.
Mr. Crisp referred to the views of Prof. Grunow on W. Prinz’s
paper on Diatoms in Thin Rock Sections (see p. 246).
Mr. Ingpen read a note on the use of diaphragms, illustrating his
remarks by drawings upon the black-board. The ordinary wheel of
diaphragms in general use was, he considered, effective only to a
certain extent; and he gave the preference very decidedly to the
sliding cylinder-diaphragm so largely adopted on the Continent,
which was in fact a modification of that devised many years ago by
Varley, in which double cylinders were used, one working within the
other. The outer one had a moderate-sized opening sliding up in
the substage, or in the ring provided for the purpose beneath the
stage, until in contact with the slide. This cylinder was lined with
cloth, to facilitate the sliding of the second cylinder, having a similar
opening in the cap. By the proper use of this double cylinder the
cone of light could be modified in the most perfect manner,—in fact
it left nothing to be desired. The plate of diaphragms devised by
Dr. Anthony, consisting of a series of apertures in a strip of vellum,
to be placed immediately beneath the slide upon the stage, did not
appear to him effective, inasmuch as at the position in which it was
Ser. 2.—Von. II. 2G
4412, PROCEEDINGS OF THE SOCIETY.
placed, the cone of rays was far too small to be affected by the size of
apertures adopted, passing, in fact, completely within the apertures.
He might apply the same remarks to the action of the calotte dia-
phragms, which he regarded as based on a wrong conception of the
action of diaphragms, He could not commend the iris diaphragm on
the ground that it required a special fitting, and could rarely be used
near enough to the slide.
Mr. J. Mayall, jun., said there was another purpose in the appli-
cation of diaphragms, not touched upon in Mr. Ingpen’s remarks,
namely, the cutting off different portions of the illuminating pencil.
The mere cutting down the diameter was the main object of the
wheel of apertures in common use, and of the cylinder diaphragms
referred to, but Dr. Anthony’s diaphragm was intended to supplement
the action of the strictly central aperture by a series that could be
easily applied to cut off more or less of the beam after all had been
done that was possible in modifying the light with the central aper-
tures,—to use a phrase of Dr. Anthony’s, “ to give the finishing touch
to the illumination.” Regarding the calotte diaphragm, its application,
as a diaphragm alone, immediately beneath the slide, was due to Mr.
Zeiss, who was hardly likely to have adopted it unless he had found
it effective. The still more recent application of it above the con-
denser must be regarded as a step in advance. Mr. Bulloch, of
Chicago, appeared to be one of the earliest to see that the diaphragms
beneath the optical combination in Gillett’s condenser, might be ad-
vantageously applied above the lenses, where the cone of rays is so
short and of such great angular extension that every variation in size
or shape in the apertures of the calotte would be effective. Mr. Switt
had also adopted the calotte in connection with the achromatic con-
denser. The iris diaphragm was effective for low powers, especially
when mounted to fit in the stage itself, as adopted by Messrs. Ross ;
but he had not been satisfied with it in connection with the achromatic
condenser. He believed there were difficulties in the construction
which rendered it almost impossible to close the aperture with suffi-
ciently accurate centering to be of real service with the condenser.
In conclusion, Mr. Mayall said that the great number of devices
that had been brought forward in recent years to cut off portions of
the illuminating pencil independently of the mere reduction of the
cone by strictly central apertures, proved conclusively that a need
was felt in that direction.
Mr. Beck said that though there might be differences of opinion
as to what was the most valuable kind, he thought no one would
dispute the great importance of a good diaphragm, which was of
extreme value in rendering visible portions of an object which other-
wise could not be seen.
Mr. Ingpen said that his remarks were merely taking things as
they stood, and did not, of course, apply to the use of the calotte dia-
phragm with the achromatic condenser. The calotie diaphragm, as
drawn by Mr. Mayall, was very effective, but almost every effect could
be obtained by a very small number of stops with tolerably small
apertures. Professor Abbe had satisfied himself of this entirely.
PROCEEDINGS OF THE SOCIETY. 443
The President read a note on the histology of the Temno-
pleuride, which he illustrated by drawings upon the black-board.
Mr. Stewart called attention to a curious change which took place
under certain circumstances in the reticulated network ; where there
was any friction going on it was found that the interstices became
filled up with carbonate of lime, and this seemed to be a case of pre-
cisely the same kind as what went on in bone-tissues under similar
circumstances. Besides the spicules in the hard tissues there was
found a remarkable exception in the structure of the teeth, which
more closely resembled silicious rather than calcareous spicules.
Mr. Hartog said that in studying the structure of these organisms
it was important to study the soft parts in connection with the hard
ones. To do this the specimen should be first stained and then
saturated with liquid Canada balsam, which should be evaporated
down to a resin: sections could then be cut through the shell and the
soft parts, at the same time showing them together in situ, and stained
as far as they could be.
Mr. Stewart said that in Koch’s method it was solid copal varnish
which was used instead of solid Canada balsam, the latter being too
brittle to enable good sections to be cut. He had seen sections which
had been made by this method, and they certainly showed the structure
remarkably well in the corals, &e.
The President said that Koch’s method was a most excellent one
as applicd to corals, but it did not answer so well for Echinoderms.
He had found it a very good plan to dissolve out the calcareous
portions with weak acid. With regard to the fossil forms they all
knew that the reticulated structure was entirely lost during fossili-
zation, when it seemed entirely filled up by calcite.
Mr. Stewart remarked that this complex network showed under
the polariscope a common axis of tension passing through the entire
body.
Professor Abbe’s paper “On All-round Vision” was read by
Mr. Crisp.
The following Instruments, Objects, &c., were exhibited :—
Mr. Crisp:—(1) “Jumbo” Microscope; (2) “ Midget” Micro-
scope; (8) “Acme” Class Microscope (see p. 251); (4) Browning’s
Portable Microscope (see p. 252).
Mr. Hartog:—Apus cancriformis and a series of sections of
Entomostraca.
Mr. Ingpen :—Zeiss Microscope and sliding cylinder-diaphragms.
Dr. Loew :—Photographs of Spirogyra nitida.
Baron Ferd. v. Mueller, K.C.M.G., &c.:—Various dried Algz
from the Phytologic Museum of Melbourne.
Mr. L. A. Sillem :—Foot of Emerald spider.
New Fellows.—The following were elected Ordinary Fellows :—
Messrs. John A. Ollard, Henry Palmer, and Henry Pocklington.
Honorary Fellows :—Professor C, Robin and Dr. L. Dippel.
2G 2
444 PROCEEDINGS OF THE SOCIETY.
CONVERSAZIONE.
The Second Conversazione of the Session was held on the 26th
April in the Libraries of King’s College, when the following objects,
&c., were exhibited :—-
Mr. J. Badcock:
Fredericella sultana and Epistylis sp.
Mr. C. Baker:
Preparations from the Zoological Station, Naples.
Messrs. R. and J. Beck:
Section of Leech and International Microscope.
Mr. Thos. Bolton :
Fredericella sultana.
Mr. W. G. Cocks:
Lacinularia socialis.
Mr. Crisp:
Various Schizophytes mounted by Dr. Zimmermann, of Chemnitz.
Mr. H. Crouch:
New Portable Microscope, and Siddall’s stage for use with
ordinary selenites.
Mr. Thos. Curties:
Section of Triton, and larva of Synapta.
Mer, ..T. Draper:
Portfolio of drawings of microscopical objects.
Mr. L. Dreyfus :
Argulus foliaceus.
Mr. F. Enock :
Heads of bees showing all the organs of the mouth in their
natural form and colour. Cédipoda cruceata, one day old;
born in England from eggs sent from Troy.
Mr. F. Fitch:
Ventral cords of blow-fly from thoracic ganglion to end of
abdomen and ramification.
Mr. C. J. Fox:
Diffraction effects produced by rectilinear and circular gratings.
Dr. H. Gibbes:
Human epididymis with spermatozoa in the tubes; section of
mammalian kidney showing ciliated epithelium in the con-
voluted tubes, and cerebellum injected and treble stained,
showing cells of Purkinge and nerves proceeding from them.
Mr. N. E. Green:
Pleurosigma formosum by side and transmitted light, and Notting-
ham deposit by side light.
Mr. J. Hood :
Cristatella mucedo.
Mr. Joshua:
Ceramium acanthonopum showing tetraspores, and Hydrurus pen-
cillatus sent from Norway by Dr. O. Nordstedt.
Mr. A. D. Michael :
Pachygnatha de Geerti showing accessory sexual organs, and
Tenuipalpus spinosus.
PROCEEDINGS OF THE SOCIETY. 445
Dr. Millar:
Rectangular network of Dendispongia Steerii.
Mr. C. N. Peal:
Experiments illustrating the effect of various kinds of illumina-
tion upon the appearances of diatoms. Micro-photographs of
diatoms by Mr. J. H. Jennings, of Nottingham.
Mr. B. W. Priest:
Arachnoidiscus japonicus in situ.
_Mr. J. W. Reed:
Crystalloids in Lathrea squamaria and in the seed of Ricinus
communis.
Mr. A. Sanders:
Stained sections of the brain of Hyperopisus dorsalis, a fish
belonging to the family Mormyride.
Mr. Sigsworth :
Double platino-cyanide of magnesium and yttrium of various
forms.
Mr. L. A. Sillem :
Volkeria pustulosa, plates of star-fish, &c.
Mr. George Smith :
Section of meteorite (U.S.A.).
Mr. James Smith:
Aphides of rose and nettle.
Mr. J. H. Steward :
Pleurosigma angulatum with 545 immersion object-glass by Hen-
soldt, Meteorite showing fluid cavities, &c.
Mr. A. W. Stokes:
Combustion and volatilization of zine, copper, iron, &ec., in the
electric are under the Microscope.
Mr. H. J. Waddington :
Stephanoceros and Melicerta.
Mr. F. H. Ward:
Section of stems of Jasminium nudiflorum and Ampelidea double
stained.
Mr. E. Wheeler:
Ruby and ruby sand section of meteorite showing cavities with
liquid or gaseous contents ; new Diatomacez from Hong Kong,
&e.
Mr. T. C. White:
Rectal papille of blow-fly and earwig.
Messrs. J. Swift and Son :
Podura scale with student’s } object-glass on improved American
Microscope.
Meetine or 10TH May, 1882, at Kine’s Cottecn, Stranp, W.C.,
James GLAIsHER, Esq., F.R.S., In THE CHAIR.
The Minutes of the Meeting of 12th April last were read and
confirmed, and were signed by the Chairman.
446 PROCEEDINGS OF THE SOCIETY.
The List of Donations (exclusive of exchanges and reprints)
received since the last meeting was submitted, and the thanks of the
Society given to the donors.
From
Blades, W.—The Enemies of Books. 3rd ed., 1881 Prof. A, Liversidge, F.R.S.
Geological and Natural History Survey of Canada. Report of
Progress for 1879-80. (8vo, Montreal, 1881).. Government of the Dominion,
Hermann, L.—Handbuch der Physiologie. Vol. iv. Part 2. viii.
and 467 pp., 58 figs. (8vo, Leipzig, 1882) .. .. .. .. Mr. Crisp.
Micrographic Dictionary, Part 11 SS So 46, . Mr. Van Voorst.
Mr. Crisp read letters from Professor C. Robin and Dr. L. Dippel
in acknowledgment of their election as Honorary Fellows.
Mr. Dowdeswell read a paper on “The Bacteria of Davaine’s
Septicemia ” (see p. 310).
The Chairman said he was very glad that they had had a paper
on so important a subject. Observations upon Bacteria were daily
acquiring more and more value, from their supposed connection with
various kinds of disease. He hoped that Mr. Dowdeswell would con-
tinue his observations upon the subject, and that he would be able to
explain the great discrepancies which he had observed to exist between
the size of the specimens he had described and those which had been
referred to by other observers.
The Chairman referred to a letter received from Mr. Ralph, the
President of the Victoria (Australia) Microscopical Society, in which
he mentioned that he expected to be present that evening. At the
last moment, however, he had been prevented from coming. He was
sure they would all hope that Mr. Ralph would be in England at
their next meeting, so that they might welcome him both as one of
their ex-officio Fellows and also as the representative of almost the
only Colonial Microscopical Society.
Mr, Burnett's note on a new form of rotating live-box was read
and the apparatus exhibited (see p. 410).
Mr. Sigsworth exhibited a spring paper-clip which he had found
very useful in fastening card cells upon slides and much more con-
venient for the purpose than the so-called “ American” clips.
Dr. Van Heurck’s views on the use of the incandescent electric
light for microscopy were briefly referred to by Mr. Crisp, who ex-
plained, by means of black-board drawings, two cases in which, in
consequence of its superior intensity, the electric light might be made
use of to extend somewhat the resolving power of an objective. Dr.
Van Heurck had recently obtained an improved form of battery which
superseded the one he originally described. He found the Swan form
of lamp to be the most suitable for microscopical work (see p. 418).
Professor Abbe’s paper “ On the Relation of Aperture and Power
in the Microscope,” Part I. (see p. 300), was read by Mr. Crisp, who
PROCEEDINGS OF THE SOCIETY. 447
referred to the complete paper as being one of the most valuable
and useful papers that had ever been brought before the Society,
dealing as it did not only with the theoretical part of the subject but
establishing also a rational standard for the practical construction of
objectives.
The Chairman considered that Professor Abbe’s paper was indeed
a most useful one, and that it would be greatly appreciated by practical
opticians.
Mr. Beck said that he considered it was an exceedingly valuable
paper, and one that would enlighten a great many persons as to the
relative value of aperture and magnifying power in regard to which
great confusion had existed. There were people who thought that if
they could get a1-inch objective with an aperture of 120°, they could
resolve difficult diatom tests. He had heard it claimed that such
glasses had been made, but although he had ordered one he had not
yet been able to get it, and hopes that might have been raised by
these announcements would be damped by the contents of Professor
Abbe’s paper. He was very glad that it had been written, because it
had been his impression for some time that Professor Abbe had been
working exclusively in the direction of wide apertures,
Mr. Ingpen was surprised to hear Professor Abbe, of all persons,
charged with an exclusive approval of large apertures, for if any one
looked at Zeiss’s catalogue, they would see at once that all the dry
lenses were of remarkably small angles, nothing exceeding 110°.
Mr. Crisp said that the most opposite notions had been held as to
Professor Abbe’s views on wide or narrow apertures. Some years
ago it was stated, at one of the Society’s meetings, that he advocated
only narrow apertures, and some correspondence took place in regard
to it in the ‘ Monthly Microscopical Journal.’ Again, later, it was
insisted that Professor Abbe considered all but wide powers useless
to the microscopist! The fact was that Professor Abbe had, since
the date of his earliest observations on aperture, advocated the main-
tenance of a proper ratio between aperture and power—wide apertures
for high powers, and small apertures for low powers—and had
always insisted on the great importance of perfecting the construction
of moderate apertures. The confusion had arisen from the fact of
Professor Abbe having shown, in connection with his theory of micro-
scopical vision, that wide apertures, and wide apertures only, gaye
true images of minute objects; but it did not, of course, follow from
that, that wide apertures were to be universally used, with low powers
and with objects unsuitable, either from their requiring depth of
vision or for other reasons.
‘Mr. J. Mayall, jun., exhibited Ross’s “ Hospital Microscope,”
the speciality of which is the fine adjustment, which is of simple
construction.
Dr. Maddox read a paper “ On Some Micro-organisms from Ice-
Water and Hail,” illustrated by a number of photo-micrographs.
The Chairman inquired how Dr. Maddox accounted for the exist-
448 PROCEEDINGS OF THE SOCIETY.
ence of the organisms which he had described. Did they come from
the atmosphere ?
Dr. Maddox thought that with regard to those from the ice of the
water-butt, they probably were in the rain-water before it froze, and
they alone survived; those found in the water from melted hail most
likely came down from the atmosphere with the hail.
Prof. F. J. Bell’s paper, “Note on the Spicules found in the
Ambulacral Tubes of the regular HEchinoidea” (see p. 297), was,
owing to the lateness of the hour, taken as read.
The following Instruments, Objects, &c., were exhibited :—
Mr. Burnett :—New form of Rotating Live-Box (sce p. 410).
Mr. Dowdeswell :—Bacteria illustrating his paper (see p. 310).
Dr. Maddox :—Photo-micrographs illustrating his paper.
Mr. J. Mayall, jun. :—Ross’s Hospital Microscope.
Mr. Sigsworth :—Spring clip.
New Fellows.—The following were elected Ordinary Fellows :—
Messrs. T. 8. Up de Graff, M.D., John Inglis, J.P., Captain A. H.
Southey, Prof. Ramsay Wright, and John Wright.
Water W. Reeves,
Assist.-Secretary.
( 13)
SR. & J. BECK,
MANUFACTURING OPTICIANS.
68, CORNHILL, LONDON, E.C.
1016, CHESTNUT ST., PHILADELPHIA, U.S.A.
FACTORY :
LISTER WORKS, HOLLOWAY, LONDON, N.
MICROSCOPES,
MICROSCOPE OBJECT-GLASSES,
PATHOLOGICAL AND
PHYSIOLOGICAL PREPARATIONS,
Materials and Instruments for Mounting
Objects, and for Students’ Use.
ILLUSTRATED CATALOGUES
DESCRI PLIVE PAMPHLETS
OF the Cheaper Forms of Microscopes forwarded upon
| Application to
es Re: 8ST. BECE,
_ 68, CORNHILL, LONDON, E.C._
( 4 )
JOURNAL
OF THE
ROYAL MICROSCOPICAL SOCIETY,
Containing its Cransacttions and Proceedings,
AND A SUMMARY OF CURRENT RESEARCHES RELATING TO
ZOOLOGY AND BOTANY
(principally Invertebrata and Cryptogamia),
MICROSCOPY, &e.
Edited by
Frank Crisp, LL.B., B.A.,
one of the Secretaries of the Society and a Vice-President and Treasurer of the
Linnean Society of London ;
WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND
A. W. Bennett, M.A., B.Sc., F. Jerrrey Bet, M.A.,
Lecturer on Botany at St. Thomas’s Hospital, | Professor of Comparative Anatomy in King’s College,
8. O. Rupuey, M.A,, of the British Museum, and Joun Mayatt, Jun.,
FELLOWS OF THE SOCIETY,
Tus Journal is published bi-monthly, on the second Wednesday of the
months of February, April, June, August, October, and. December. It
varies in size, according to convenience, but does not contain less than
8 sheets (128 pp.) with Plates and Woodcuts as required. The price to
non-Fellows is 4s. per Number.
The Journal comprises:
(1.) The TRANSACTIONS and the ProcrEpines of the Society:
being the Papers read and Reports of the business trans-
acted at the Meetings of the Society, including any _
observations or discussions on the subjects brought
forward.
(2.) Summary of OurrENT Researcues relating to ZooLocy .
and Borany (principally Invertebrata and Cryptogamia, :
with the Embryology and Histology of the higher Animals
and Plants), and Microscopy (properly so called): being =
abstracts of or extracts from the more important of the =~
articles relating to the above subjects contained in the =
various British and Foreign Journals, Transactions, a
from time to time added to the Library.
‘Authors of Papers printed in the Transactions are entitled to 20 copies
of their communications gratis. Extra copies can be had at the price of
12s. 6d. per half-sheet of 8 pages, or less, including cover, fora minimum
number of 100 copies, and 6s. per 100 plates, if plain. Erceerace Pi. area:
P.0.0. is requested. $ = *
All communications as. ‘to the Journal should be Saideensed to the. eet
Editor, Royal nqciantaeare Society, King’s College, Strand, W. C. ae
"Published for the Society by be
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M. PILLISCHER’S NEW MICROSCOPE,
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A WEEKLY RECORD OF SCIENTIFIC PROGRESS. ILLUSTRATED.
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( 18 ) -
MICROSCOPIC OBJECTS.
Classified Catalogue. ‘ NEW EDITION FOR 1880. Post Free and Gratis.
Specimens of the highest attainable perfection in every branch of Microscopy. New and
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Swi rT & SON
Are now adapting to their ‘* Challenge ” and other Microscopes, :
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Also SWINGING SUBSTAGE RADIAL ILLUMINATOR, as well as
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Catalogue fully Illustrated, and Circular, containing particulars of the above, by post
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STUDIES IN MICROSCOPICAL SCIENCE.
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interested in the progress of the Natural Sciences. _ Each Number is illustrated’ and accompanied by— —
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The terms of subscription, payable stictly in advance, including Postage, sre—In Great Britain, Quarterly,
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HOW’S MICROSCOPE LAMP. THE MINIATURE MICROSCOPE LAMP, 3; nae
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Rock SECTIONS AND OTHER MicRoscoric OBJECTS. gy. eRe A
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( 19 )
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Gold Medal, Paris Exposition, 1867.
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ESTABLISHED 18580.
THE
ROYAL MICROSCOPICAL SOCIETY.
(Founded in 1839. Tneorporated by Royal Charter in 1866.)
The Society was established for the communication and discussion
of observations and discoveries (1) tending to improvements in the con-
struction and mode of application of the Microscope, or (2) relating to —
Biological or other subjects of Microscopical Research. eP
It consists of Ordinary, Honorary, and Ex-officio Fellows.
Ordinary Fellows are elected on a Certificate of Recommendation
signed by three Fellows, stating the names, residence, description, &¢., of
the Candidate, of whom one of the proposers must have personal know-
ledge. The Certificate is read at.a Monthly Meeting, and the Candidate
balloted for at the succeeding Meeting.
The Annual Subscription is 2/. 2s., payable in advance on election,
and subsequently on Ist January annually, with an Entrance Fee of 21. 2s,
Future payments of the former may be compounded for at any time for |
311.10s. Fellows elected at a meeting subsequent to that in February are
only called upon for a proportionate part of the first year’s subscription,
| and Fellows absent from the United Kingdom for a year, or permanently
residing abroad, are exempt from one-half the subscription during absence. _
Honorary Fellows (limited to 50), consisting of persons eminent —
in Microscopical or Biological Science, are elected on the recommendation
of three Fellows and the approval of the Council.
Ex-officio Fellows (limited to 100) consist of the Presidents for
the time being of such Societies at home and abroad as the Council may —
recommend and a Monthly Meeting approve. They are entitled to receive
the Society’s Publications, and to exercise all other privileges of Fellows,
except voting, but are not natires to pay any Entrance Fee or Annual
Subscription. :
The Council, in eo the management of the affairs of the Society
is vested, is elected annually, and is composed of the President, four Bocas
Presidents, Treasurer, two Secretaries, and twelve other Fellows.
The Meetings are held on the second Wednesday in each cits ea?
from October to June, in the Society’s Library at King’s College, Strand, shes
_ WC, (commencing at 8 pt.) Visitors are admitted by the introduction of
Fellows. :
. In each Session two additional evenings are devoted to the exhibition’ Se NR
of Instruments, Apparatus, and Objects of novelty or interest relating to re
|. the Microscope or the subjects of Microscopical Research. ee ee
~The Journal, containing the Transactions and Proceedings of the el eee
Society, with a Summary of Current Researches relating to Zoology and | —
Botany (principally Invertebrata and Cryptogamia), Microscopy, &e., is | —
| published bi-monthly, and is forwarded gratis to all Ordinary and Ex-ofticio Pie St
| Fellows residing in countries within the Postal Union. © ee
The Library, with the Instruments, Apparatus, and Cabinet ee pin
Objects, is open for the use of Fellows on Mondays, Tuesdays, Thursdays, ae
and Fridays, from 11 A.m. to 4 P.m., and on Weanssieye. from 7 to 10 Par |
It is closed during August. — apes
Forms of proposal for Fellowship, and any further information, may be obtalehel id Se
- : : application to the Secretaries, or ee ee at the bee ats od wer “ing A
College, Strand, W.C. eben
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