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JOURNAL

OF THE

ROYAL
MICROSCOPICAL SOCIETY:

CONTAINING ITS TRANSACTIONS AND PROCEEDINGS,

AND A SUMMARY OF CURRENT RESEARCHES RELATING TO

ZO OLO GS AND Bot AN
(principally Invertebrata and Cryptogamia),
DILCROSCOP YY, cee.
BOT:
Edited by GA
FRANK CRISP, LLB. 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.LS., F, JEFFREY BELL, M.A., F.ZS.,
Lecturer on Botany at St. Thomas's Hospital, Professor of Comparative Anatomy in King’s College,
JOHN MAYALL, Joun., F.Z.S., R. G. HEBB, M.A., M.D. (Cantaé.),
AND

J. ARTHUR THOMSON, M.A.,
Lecturer on Zoology in the School of Medicine, Edinburgh,

FELLOWS OF THE SOCIETY.

FOR THE YEAR
1889.
Part]:

PUBLISHED FOR THE SOCIETY BY

WILLIAMS & NORGATE,
LONDON AND EDINBURGH.

Saas The Journal is issued on the second Wednesday of
February, April, June, August, October, and December.

tay
gh. :
r 1889. Part 4. AUGUST. { *°pieo. snows,

JOURNAL

OF THE

ROYAL
MICROSCOPICAL SOCIETY;

CONTAINING ITS TRANSACTIONS AND PROCEEDINGS,

AND A SUMMARY OF CURRENT RESEARCHES RELATING TO

ZooLucGyY AND BOTAN WZ
(principally Invertebrata and Cryptogamia),
MICROSCOPY, Szc-

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.L.S., F. JEFFREY BELL, M.A., F.ZS.,
Lecturer on Botany at St. Thomas's Hospital, Professor of Comparative Anatomy in King’s College,
JOHN MAYALL, Jun., F.ZS., R. G. HEBB, M.A., M.D. (Cantaé.),
AND
J. ARTHUR THOMSON, M.A.,
Lecturer on Zoology in the School of Medicine, Edinburgh,
FELLOWS OF THE SOCIETY.

WILLIAMS & NORGATE.
es LONDON. AND EDINBURGH. 4

PRINTED BY WM. CLOWES AND SONS; LIMITED,] (STAMFORD STREBT AND CHARING CROSS.

CONTENTS.

——

TRANSACTIONS OF THE SoornrTy—

Waters or tHE Unitep States. By Dr. Alfred C. Stokes.
CPTatG; RE) aoe -

VITI.—Anpprtionat Norte on THE ForaMnirera oF THE Loxpon Chay
EXPOSED IN THE Drainage Works, PICOADILLY, Lonpon, IN

1885. (Plate XI.) oo ee es oe oe oe oe Ch ae 483
SUMMARY OF CURRENT RESEARCHES.
ZOOLOGY.
A. VERTEBRATA :—Embryology, fuel and General.
a. Embryology. is
Minor, c S.—Uterus and Embryo... .. ery ck opr heey rae Bote)
Tarani, A.—Fecundation and Bopientalion of Ova of Rats |. Freee: SOO
Cunnineuam, J. 'T.—Keproduction and Development of Teleostean Fishes apis we AON
B. Histology.
Frommann, 0.— Vital Processes in Living: Celery. se eae Spaeth aeae oar
Morrvurco, B.—New Formation of Cells .. anette Sate em ene hes
Tanaz, F. Vie ie between Cell-body and Nucleus i; i. tee ees
Fatzacappa, EK.—Nerve-cells in Birds .. : . ee (494
Gace, 8S. H—Form and Size of Red 1 Blood-corpueces: of “Adult and Larval
Lampreys .. v5 se owe a Pp ste Hh |
y. General.
STUHLMANN, F.—Fresh-water Fauna of Hast Africa .. .. «2 «se 0» «s «6 494
B. INVERTEBRATA. s
Cuténot, L.—Lymphatic Glands of Cephalopods and Decapodous Crustacea .. -.. 495.
Mollusca. ;
a. Cephalopoda. ee
Eanes Structure of Siphon and Funnel of Nautilus Pompilins eae eee EATS
Brock, J.—So-called Organ of Verrill in Cephalopoda .. «. «« «ce os « 496
B. Pteropoda.
PELSENEER, P.—Morphology of Spinous Saes of Coin auomnaue Preropods ae eeees? A9G
y. Gastropoda.
Bovuran, L.—Ventral Nervous Mass of Fissurella 9... eet as Gee Oe
Prez, J.—Descent of Ova in’ Helix ea oft ciop eka aeeO W
ScHALFEsEFF, P.—Anatomy of Clione Vimacina Per Spee Sei3 Se yb
GARNAULT, P. —Reproductive Organs of Valvata ‘piscinalis eae wee bee See
5, Lamellibranchiata. :
Méniéicaux, A.—Morphology of Teredo .. 3: awh ee nig py eige se
Necmayr, M.—Origin of Unionidz ee, eed ee ae
Molluscoida,
a. Tunicata.
Dayivorr, M. v.—Developmental History of Distaplia magnilarva.. :

PAGE
VilI.—Norticzs or New PeEritRicnovs INFUSORIA FROM THE FREsH

ATT

+» 498

Ca)

8, Bryozoa.
’ Denpy, A.—Anatomy of an Arenaceous Polyzoon ~.. ai aa

Prouno, H. .—Structure and Metamorphosis of Larva of Flustréila hispida
Arthropoda.
Parren, W.—Segmental Sense-Organs of Arthropods .. 2. 6s ae eg nee

; a, Insecta.
-Henxixc, H.—Formation and Fate of Polar Globules in Eggs of Insects

Daut, F., & D. Saanr—Viston of Insects .. oe ne we ee eee te
BeRTKAU, P. Bodie ib abl gl Ut, GAstpOvacMes. i Foes ek teee A Tee eee es
> Wasmann, E.—Myrmecophilous Insects... 20 S00 ae ee ee i oe ee ee

SKERTCHLY, ss B. J.— Butterflies’ Enéinies .. St BS BT ARO nT

Mrncazzin1, P.—Alimentary Canal of Larval Lanelicorns: Cs aia ae ahaee

yeaa: Mie Beer ond: Powers. 2." oak) ss: eek Be ae ee RPI See

Car.et, G.—Stigmata of Hymenoptera.. .. seen on

VorLTzKOW, A. .— Development in Egg of Musca vomitoria .
Miz, J.—A Spinning Dipteron

Low, F.— Bio rele of Gall-producing Species ‘of Clhermes : ee ; dee a Pian okay
“es he Sars ‘gg of Melolontha vulgaris 4; Le ER TP PEG EOE Te
Hassn, E ei sees of Ld: 0 deere eens ns cinta RES A ES EA Saga
8. Myriopoda.
CHALANDE, J.—Spinnerets of Myriopoda .. Se OS eC ae ph cos eat paen eta
Pocock, R. I.—Myriopoda of Mergui Arehipelago Pies ePaper eta ai Rae OSE
. Prototracheata.

_ SHELDON, eo Anat of Ovum in Cape and New Zealand Species of Peripatus
6. Arachnida.

Moun, A. D.—Life-histories of Ciaviphape 2 domesticus and G. one os

- Méenty, P.—Encystation of Glyciphagus .. iy x
Kornrke, F.— New Genus of Hydrachnids .. Hag Cee ee
Montez, R.— Accidental Parasitism on Man of Tyroglyphus farinzs.. oar pate ne ain
Trovrssant—Marine Acarina of the Ooasts of France... is

Sonaus, R. v.—Marine Hydrachnida .. Fe ESE Nar ab eet Weenie We
ApteRz, G.—Morphology and Larve of Pantopoda- SF SIP Y TS jae R NY Aiba Yee e

e. Crustacea. —

Rossnskaya, M.—Development of Amphipoda oi ely seeps RET eS
Norman, A. M.—British Amphipoda .. 2. 42 ee ee
Cuon, C. Rp te Family of Scinidz

‘Brapy, G.5., . MN oRmAN—Ostracoda of North Atlantic and d North-western
Europe =
Grarp, A., & J: Bonwier—Parasitic Crustacda.. f2
ay Morphology and Systematic Position of the Dajte “a
Koruuer, R. —"Fequmentary Coverings of Anatifer and Pollicipes .. «+
Vermes.
a, Annelida.
Rove, L.— Influence. of Nervous System of Annelids on Symmetry a the Bais y
Soutien, A.—Epidermis of Serpulidz .. as

BEDDARD, F.. E.— Marine Oligochzxta of Plymouth

Fiercuer, J. J.—Australian Earthworms ..
BepparD, F. B.— Green Cells in Intequment of Aeolosoma tenebrarum ..
Wurman, ©. O.—Anatomy of Hirudinea. .. pae reaecr es
greed E. A.—Reproductive Organ of Phascolosoma Gouldii =. i

B. Nemathelminthes.

Gotpr, E. A.—Coffee-Nematodeof Brazil... eee ce te we te we
- Srosstcs, M.—Physaloptera .. Peet See RN tees yb
- Kyiprrer, P.—Female Genital Duets of Acinnthocepkata SS See Rese ee ERE Se

PAGE
499
501

501

502
502
503
503
504
504
904
505
505
506
506
506
506

507
507

507

908
509
509
509
509
509
509

910
oll
512

912
512
514
913

514
515
515
515
515
516
518

518
518
519

(4)

y. Platyhelminthes. PAGE.
Wenpt, A.—Gundauloz ... dt a ae i ae a eee
Bireer, O.— Nervous System of Nemertines.. Pp Pa aa ER eS
Linstow, von—Helminthological Notes... .. Perit wer a is Pe
Stosstcu, M.—The Species of Distomum in Amphibians Foo gle <2 jo wen Sear ae eae
Listow, von-—Anatomy of Phylline Hendorfitt .. s,s» se ee we ee we DAD
Monticetui, F. §.—Nervous System of Aniphen lee wok fGct agnor hen pena
iy Cercaria setifera .. «. go Slee agin be eaaag pies ene
Crery, C.—Structure of Rolenophorus We top Dies hu we 5 wage akan tee a 523
5. Incertee Sedis,
Ming, W.—Rotifers Parasitic in Sphagnum © 1. se +e en tee te OB
Keuuicorr, D. S.—American ROL fEP Os oe ioe Kas oi belies aah tape eee oe eae aes
Bourne, G. C.—Tornaria in British Seas... 12 ae ve ee we we we we ORD
Echinodermata, oe
Lupwie’s Echinodermata . wii} Ret em. ieee en eee antes
Hamann, O.—Anatomy of Ophiuroids and Crinoids MY eC ster ne ate ns rd)
JickELI, C. F.—Nervous System of Ophiurids .. ee 00 se ee we we we OT
Hamann, O.—Morphology of Crinotds’.. ss % os oe a» oe ne we we ae 028
Beui, F, Jurrrex—Large Starfish ee prt sn
Ives, J. E.— Variation in Ophiura panamensi and O. teres... er? dee ee DAO,
Coelenterata.
MarsHaui, A. Mitnes, & G. H.. Rowrius Seen ues i Mergui Archiplag oo 529
M‘Morricx, J. P.—Lebrunia neglecta ..~ .. na ee ae oe 929
Siuirer, CG. P.—Remarkable Actinian® .. sui st sn) oe Uwe) aa) 20 ne ee ew
Kocu, G. v.— Caryophyllia rugosa .. SA Se 9 aes Sete OU:
VANHOFFEN, E.—Semxostomatous and Rhizostomatous Medusz.. Fa ae eee Seo
Cuun, C.—Siphonophora of Canary Islands... ss ee ne ne te we ws, 30
Fewses, J. WauteR—New Athorybia .. se 2k ae Jen ee ee ae ae ae
ScHEWIAKOFF, W.—LHyes of Acalephe .. -+ ee 46 an ne pe ne ee 532
Porifera. ;
Tnmy, J.—Clona= on oes sa oe at kee me ie aime ee
Protozoa. z ‘ .
Fapsre-DomerGue—Functional Differentiations in Unicellular. Betude Shas thes 534
GruBer, A.—Maupas’ Researches on Ciliata =... su ce we we ne we we ODE
FABRE-DOMERGUE—Two New Infusorians .. .. ss s+ ss se «8 er se 980
ANDERSON, “a H.—Anoplophrya aeolosomatis .. ance hem gan eee Lee
eta F.— Formation of Spores of Gregarie of Harthworm «036 ©
Luz, A.—Cystodiscus wmmersus—a paghe ee ec found in the gall-bladder of :
Brazilan Batrachia pele aes Sree Pam ea re ee Sie wo Aye
BOTANY.
A. GENERAL, including the Anatomy and Physiology”
of the Phanerogamia.
a. Anatomy.
(1) Cell-structure and Protoplasm. :
SrrasBuRGER, E.—Growth of the Cell-wall .. 2. se as em eae | oe se D8
Manein, L.—Structure of the Cell-wall . ae MMP ENE arrestee ST te)
Vrins, H, pe—Permeability of Protoplasm for Urea .. 538.
Kroricky & Bie~kowsky—Diosmose through the Cellulose-pellicle of Phragmites
contr ieds ‘ Fe ate a Breas 539
PFEFFER, W — Reduction of Ripe in the living- cell EO ae Da ae Poe

539

(oa)

(2) Other Cell-contents (including Secretions).

Scuuncg, E.—Chemistry of Chlorophyll... eecvobe Wen” ie
Moutscu, H.—Formation of Chlorophyll by Conifers i bi tlia Wark. a6. as uy hae
Boum, J.—Formation of Starch in the Leaves of Sedum spectabile” ..

MOELLER, H.—Mode of occurrence of Tannin in Plants

(3) Structure of Tissues.

Ross, H. an ale Tissue and Periderm in leafless plants...» + +» +
Paprennetm, K.—Closing of the Bordered Pits in ania Rite DAwy. os ways ewe
TAGRIEE, M, O.—Structure of Lecythidacer.. .. A ites Pros: eer Re.

(4) Structure of Organs.
aie bea E.—Anatomy and Chemistry of Petals sakceni ee

RAtuay, E.—EHxtrafloral Nectaries.. .. Sue Se RU aa ae a aor ee op
Correns, E. C.—Extrafloral Nectaries of Pigosuidie sic he
Merenan, T.—Elastic Stamens of Composite... .. RE UAE SOP Pe ae oe
35 » Glands on the Stamens oF Caraee yllacer Preis meine wae A went ee
Heimert, A.— Fruit of Nyctaginer .. Era Paper ag tie
LorseL, O.—Anatomy of Leaves .. .. pec gie Sek Spee aga wes chests ee
Krasse, G.—Fixed daylight position of Leaves as oneal

Biscun, M —Structure and Function of the Bladders ‘of Uiricutaria
ScuwENDENER, S.—Stomates of Graminex and Cyperacexr
STRUBING, O.—Stomates of Conifere .. oe ae ae we

TURNBULL, R.—Water-pores in Cotyledons .. 2. se ae tenet ee
Frot, L.— cae a of Trees .. .. Piers ieee
lator tet E.— Bacillax Tumours of the Olive and of Pinus halepensis ae Page oa
De.rino, F.—Tubercles on the Roots of Galega officinalis .. .. ss. ++ 08 we
Histncer, E.—Tubercles of Ruppia and Zannichellia .. Page ear aes OR ee
Borzi, A.—Lateral Roots of Monocotyledons.. .. 2. ee se tte wwe

B. Physiology.
(1) Reproduction and Germination.
Vaiss, H. pse—Intracellular Pangenesis =... 4. ae

ee ROR at Nn eer acer rae pte ¥
‘Lupwie, F.—Fertilization by Braghees sc Wek Coe oe Ce toe

(2) Nutrition and Growth (including Movements of Fluids).

WortTMAnn, J.—Physiclogy of Growth .. 6. ss nate ene weet
Wiesner, J.—Descending Current of Water... wah ties’ 26 eNpu we
Dovrior, H.—Influence of Light on the Development of Bark . ae
Guupr, L, A.—Periodical Activity of the Cambium in the Roots of Trees Apa e
Mayen, L.— Penetration and Escape of Gases in Plants ., .. 0s ve oe we
FRANK, B.—Assimilation of Free Nitrogen by the Lower Organisms... .s «»

(4) Chemical Changes (including Respiration and Fermentation).

Loum, C. Pc sebog of the Fig.. PSOE Aer OFS Me a ep

leis .—Process of Oxidation in Living Cells Eat RE ue ak De a oe

Zor‘, W.—Oxalic Fermentation 1. se ee ne eet tee
y- General.

Gorset, K.—Young State of Plants... .. ..
Soraver, P.— Tan-disease” of Cherries
Harric, R.— Diseases of Trees .. ..

B. CRYPTOGAMIA.

Cryptogamia Vascularia.

Cuvuncu, A. H.— Aluminium in Vascular Cryptogams ihe eat a ie, Ree
Farmer, J. B.—Germination of the Megaspore of Isoetes., .. «1 6s ae

PAGE

539
S+1
541
541

541
542
942

542
543
543
544
544
544
544
545
545
545
946
546
546
546
546 —
547
547

547
548
548

548
548
549
549
549
550

550
550
550

550
dol
dol

551
ool

es

GuienaRD, L.—Antherozoids of Ferns ...

SABLON, LECLERC Du—Stem of Ferns

Lows, E. J.—Varieties in Ferns .. as
RasBeENHOoRST's Cryptogamic Flora of Germany (Fasoutar Cryptogams) oF
Srenzet, G.—Tubicaulis.. ..

Muscines,
Amann, J.—Leptotrichic Acid sighs toe PANN wake eet
Gennes, A.—Mosses from New Guineas, -.. Gciaanea
GuienarD, L.—Antherozoids of Hepatice and Mosses hepa
HABERTANDT, H.—Geotropism of the Rhizoids of Marchantia and Lunularta. fe

Algee.

Picoone, A. — Connection of the geographical distribution of mee iit. the @ chemical

nature of the substratum

ASKENASY, -E., ann OTHERS—Algz of the * Gazelle’ ? Expedition Bae cee Pacman
WILLE, N.—Development of Tissuesin Floride® .. 00° vee ae ae Ae at

Rosenvines, L. K.—Frond of Polystphonia ber hee
Wie, N., anp J. G. AGarpH—Apical Cell of. Lomentaria and Champia Siete
BAneen, C. A—Bulb of Laminaria bulbosa = een ee
Varies, H. DE—Contraction of the Coren es of Spirogyra eee palev an
Wiipreman, E. De—Variation in Desmids .. Bee!
MouRBAY, G., & L.A. hears eae oe
Works, (epee — Urospora Fs SoS aeons

TONI,. GB. DE—Clionyphe .. eee ees

Murray, G., & L.A. Booptz—Avrainvillea

Nou, F.— —Cellulose-fi bres of Caulerpa .. gs See Bitar es

Kiem, L.—Volvox .. SGPC Oca

a Sir W., & D. P. Penuattow—Ne ematophyton ins

Fungi,
Zorr, W.—Fungus-pigments _
Kirasato, §.—Musk-fungus ...
GiaRp, A.—New Eniomophthoraceze
Maenus, P.—Urophlyctis Kriegeana sp. n.

KircayEr, O.—LHlzomyces, a new type of Fungi «. 3 os Ae : a Sep a

Bonnier, G.—Synthesis of Physcia parietina .. nae ita omene pene

Cooke, M. C., & G. Masses—New development of Enphelis RRR eye a

Rovmecvine, C.—Disease of Chestnut-trees.. .. Piet

Mryasz, Kingo—Léfe-history of Macrosportum parasitieum ssa Choate Sweet stent Menge

CAVARA, F.— American “ Bitter-rot” Se ree ee er
Cosrantin, J.—Cladosporium her Barun 258 3 oe Se ee
Lupwie, R.—Microscopic twining Fungus x

Direten, P.—Heterospory of Gymnosporangium a i, ‘ - ee 5 ee a :
SoravEr, P.—Mildew of the Apple... .. .. Baht) BAe hice eh cae ete RC aR ee tate

KLpBABN, H.—Uredinezx of Pinus Strobus per nig bel eg A CNS ARI ee eee ae eas
PATOUILLARD, N.—Coleopuccinia .. - pal renieate
CosTantin, 3 pe — Tulasnella, Prototremella, and Pechylerigna a ae A
Marre.ui, U.—Phosphorescence of Agari icus olearius . aie
Arkinson, G. F.—Phosphorescent Mushroom

Beck, G. Rirrer v.—Poroptyche, a new genus or Poly more Cz eee Ae
AMANN—Mycose on the Sporange of Mosses .. . nie Fath eae er acai etd
Protophyta

a, Schizophycez.
Gort, C.—Peroniella, a New Genus of Schizophycezx

Connincuam, D. D.—Stomatochytrium, a new genus of Endophiytie Profoooccaces,

HANsGire, A. —Tetraedron ? bie dey
TERRY, W. A.—Movements of Diatoms ‘and Oscillaria oat) Seki aegis Wow oe
Stn, T. F.—Valve of Pleurosigma —.. TUNEa ON OES RL, tore h
Cain, C. H., & BE. A. Scavutze— Fossil Marine Diatoms 3 oo fe

: ‘PAGE :

Cts

Maccutati, L.—Synedra pulchella Ktz., var. abnormia
. abekgee A:— Classification: of Cyanophycea
» Pranti, K.—Parasitism of Nostoc meee ks

B. Schizomycetes.

Wrinocrapsky, T., & A. Hansarra—Morphology and Physiology ee the Peta
Bacteria ..

Housoewntxorr—Baeteria which produce Sulplureted Hydrogen seo
Jackson, C. Q.—Bacillus of Leprosy ‘ Aes ces
Cuavyrnau, A.—Vaccinal Properties of Microbes.
Huerre’s Bacteriology ..
Marvcct, A. — Tuberculous Injection of the Fowl: “embryo “3
KARLINSKI, J.—Bacillus murisepticus pleomo? plas a new pathogenio Schisomyoete
Firtscu, G.— Variations of Vibrio Proteus... i ae
Nuvuavuss, R.—Flagella of the Cholera Bacilli Bees:

ESN P., & G. SANNA-SALARIS—Glischrobacterium oe
Heinz, A _—Mucous Disease of Hyacinths .. 6. 4a ey
Tanoysky, O. G.—Bacteriology of Snow... we we

MICROSCOPY.
a Instruments, Accessories, &c.

(6) Miscellaneous.
Govt, G.—* The Compound Microscope invented by Galileo”

PAGE
566
567
567

567
567
568
568
569
569
570
570
571
571
572
572

574

APERTURE TABLE.

0-66 | 82° 36’ 59° 30’ 51° 28' 63,631 68,972 83,819 ©
0-64 | 79° 36’ 57° 31’ 49° 48’ 61,702 66, 882 81,279
0°62 | 76° 38’ 50° 34’ ASOD. 59,774 64,792 78,739.

Corresponding Angle (2 u) for Limit of Resolving Power, in Lines to an Inch, , ‘| Pene-
Numerical} aa eee oN ee Re Re trating -
Aperture. || Air Tater TOROS CREO White Light. | (Blue) Light. | Photography. “| Power.
SEES i Reena a mMersrow Fr = 05269 pw, | (A= 074861 gu, | (A = 0"4000 m, 2 aoe, EN
amalie= By) 1p ce ete LD a Atala Line E.) Line F.) near Line ih.) | - 3 a
1°52 we a 180° 0’ 146,543 158,845 193,037 | 2°31 *658
1-51 | es ae 166° 51’ 145,579 157,800 191 , 767 ‘ f° +662
1-50. |] £3 a 161° 23’ 144,615 156,755 190,497 Zi "667
1:49 | * oie 157° 12' 143,651 155,710 189,227: -2°220 § “671
1°48 H cs sr 153%:39! 142,687 154, 665 187 ,957- ah “676
1-47 =| 5 ot 150° 32’ 141,723 153, 620 186,687 % “680
1-46 es we 147° 42’ 140,759 152,575 185,417 ; “f- *685
1°45 i] de es 145° 6’ 139,795 151,530 184,147 “10% +690
1°44 | “ie a 142° 39! 138, 830 150,485 182,877 -074 - +694
42452 oe “3 140° 22’ | 137,866 | 149,440 | 181,607 -045. | +699
1:42 es < 138° 12° 136,902 148,395 180,337 | 2: +704
1°41 ea a 136° 8 135,938 147,350 179,067 ~*709
1:40 a se 134° 10’ 134,974 146,305 177,797 — é | 714
1:39 ey, 53 132° 16’ 184,010 145.260 176,527 F fF +719
1:38 aN “ 136° 26’ 133,046 144,215 175,257. 1:90: *725
1:37 ee a 128° 40’ 132,082 143,170 |; 173,987 : _ 729
1:36 as AA 126° 58’ 131,118 142,125 172,717 < “730
1°35 ss 5 125° 18’ 130,154 141,080 171,447 4 1- “TAL
1:34 ne = 123° 40’ 129,189 140,035 170,177 | -1: *746
1°33 32 180° 0’ | 122° 6 128, 225 138,989 168,907. 3 ea iy
1:32 oe 165° 56’ | 120° 33’ 127,261 137, 944 167,637 2 “758
1°30 = | 155° 38’ |.117° 35’ 125,333 135, 854 165,097 | 1: +769
1:28 st 148° 42’ | 114° 44’ 123,405 133,764. |- 162,557 |. 1: ; 1781
1-26 are 142° 39’ | 111° 59’ 121,477 131,674: | 160,017 "20 7794
1:24 ae 137° 36’ | 109° 20° 119,548 129,584 157,477 | 1: *806
1:22 a5 133°. 4’ | 106° 45’ 117,620 127,494 |: 154,937 | 1+ *820
1-20 oe 128° 55’ -| 104° 15’ | 115,692 125,404 152,397 -1:440- *833-
1°18 eG 5 IAS yedereers anaes joe LO Weees) ty 113,764 123,314 149, 857 Le *847
1:16 Spe | AOD: 99° 29! 111,835 121,224 147,317 © o % * 862
1-14 AS 118° .0’ See ba bd 109,907 119,134 144,777 I °877
1-12 Bie 114° 44’ 94° 55! 107,979 117,044. 142,237 * +893
1°10 es 5 111° 36’ 92° 43! 106,051 114,954 139,698 ‘210° | +909
1:08 Se 108° 36’ 90° 34’ 104,123 112,864 | 137,158: “166- *926
1:06 ap 105° 42’ 88° 27" 102,195 110,774 134,618 -124 | -943-
1:04 ie 102° 53’ 86° 21’ 100,266 108, 684 132,078 5 | 962
1:02 ag 100° 10’ 84°. 18° 98,338 106,593 129,538 “0: “980
1:00 180° 0’ oy ieee) 82° 12 96,410 1045503 126,998 - | 1-000
0-98 Ey eee y 94° 56’ 80° 17’ 94,482 102,413 124,458 1:020
0:96 147° 29’ 92° 24’ 78° 20! 92,554 100,323 121,918 J 1:042 -
0:94 | 140° 6’ 89° 56’ 76° 24’ 90,625 98,233 |. 119,378 1-064
0-92 | BB 3225 1" 87° 32’ 74° 30’ | 88,697 96,143 116,838 - 1087
0-90 || 128° 19’ 85° 10’ 72° 36’ 86,769 94,053 114,298. T-111
0-88 | 123° 17’ 82° 51’ 70° 44’ 84,841 91,963 111,758 1°136_
0-86 _|| 118° 38’ 80° 34’ 68° 54’ 82,913 89,873 109,218 1/163
0°84 || 114° 17’ 78° 20' 67° 6 80, 984 87,783 106, 678 1-190
0-82 | 110° 10’ 76° 8’ 65° 18’ 79,056 $5,693 104, 138 1-220
0-80 _|| 106° 16’ 73° 58’ 63° 31’ 77,128 83,603 101,598 - | 1-250
0°78 || 102° 31’ 71° 49’ 61° 45’ 75,200 81,513 99,058 1:282
0-76 || 98° 56’ 69° 42’ 60° 0’ 73,272 79,423 96,518 17316
0°74 95°o28" 67° 37’ 58° 16’ 71,343 77,333 93,979 1°351
0-72 - || 92° 6’ 65° 32’ 56° 32’ 69,415 75,242 _ 91,489 1°389
0-70 =|) -88° 51’ 63° 31’ 54° 50’ 67,487 73,152 88,899 -1°429
0°68 ~| 85° 41’ 61° 30’ 93°. 9! 65,559 71,062 86,359 7 1471
1:
i
1:
1y-
1:
1:
1:
1:
1,2

0-60 || 73° 44’ | 53° 38’ | 46° 30’ 57,846 62,702 76,199

0-58 || 70° 54’ | 51° 42' | 44° 51" | 55,918 60,612 73,659 724
0°56 || 68° 6 | 49° 48’ | 43° 14° | 53,990 58,522 71,119 786
0°54 || 65° 22' | 47° 54’ | 41° 37° 52,061 56,432 68,579 852
0-52 | 62° 40° | 46°° 2’ | 40° 0’ | 50,133 54, 342 66,039 923
0°50 | 60° 0 | 44° 10° | 38° 24 | 48°205 52,252 63,499 “000
0:45 || 53° 30’ | 39° 33’ | 34° 27 | 43,385 47,026 | 57,149 222
0-40 | 47° 9 | 35° 0’ | 30° 31’ | 38.564 41,801 50,799 2-500
0-35 | 40° 58’ | 30° 30’ | 26° 38’ | 33,744 36,576 44,449 | 2-857
0°30 | 34°56’ | 26° 4° | 99° 46’ 28,923 31,351 38,099 |: 3°338
0:25 28° 58’ | 21° 40' | 18° 56’ | 24.103 26,126 31,749 . 4-000
0-20 §| 23° 4° | 17°,18' |. 15° 7 19, 282 20,901 25,400 : 5-000
0-15 17° 14’ | 12° 58’ | 11° 19’ 14, 462 15,676 19,050 6-667
0-10 11° 29' | 8° 38" 7° 34’ 9,641 10,450 12,700 10-000
O05. | 5°44 | 4° 18’

Be 46’ 4,821 5,226.3) 7 8,350 -003 [20-000

COMPARISON OF THE FAHRENHEIT AND CENTIGRADE THERMOMETERS.

. Fahr. Centigr, Fahr. Centigr. Fahr. Centigr Fahr. Fahr Centigr
Pak NES ee ae)
°o ° ° f°] ° ° ° ° °o °
212 100 58 70 104 40 50 10) - 4 - 20
0-2 99 156"2 102°2 89 48-2 9 - 58 | =2]
210 98°89 156 68:89 102 38°89 8:39} - 6 - 21°11
2084 154°4 100°4 38 46°4 8 - 76 | -22
208 97°78 154 67°78 100 87°78 46 7784- 8 — 22°22
206°6 152°6 98°6 37 44°6 7 - 94 | -938
206 96°67 152 66°67 98 36°67 44 6°67 | -10 — 23°33
204°8 150°8 96°8 36 42°8 8 = 11°2 | -24
95°56 150 65°56 96 35°56 42 5-56] —12 — 24°44
95 149 5) 95 35 41 5 -13 - 25
202 94°44 148 64°44 94 34°44 40 4°44] —~]4 — 25°56
201°2 94 147°2 64 93*2 84 39°2 4 - 14°8 | -236
93°33 146 63°33 92 33°33 88 3°33 | -16 — 26°67
199+4 93 145°4 6 91°4 83 37°4 3 - 16°6 | -27
198 92°22 62°22 90 32-22 36 2°22] -18 — 27°78
197°6 143°6 89°6 82 35°6 2 — 18°4 | -98
196 91-11 142 6111 88 31°11 384 l-ll | - 20 — 28-89
1958 141-8 87°8 81 33°8 1 — 20'2 | -29
194 90 140 60 86 30 32 0 - 22 - 30
192°2 89 138°2 84-2 29 30°2 pte | — 23°8 | =-81
192 88-89 138 58°89 84 28°89 30 = lllj] —24 =- 3lell
190°4 13864 82-4 28 28°4 - 2 —- 25-6 | -382
190 87°78 186 57°78 82 27°78 28 - 2:22] -96 — 32°22
188°6 134°6 80°6 27 26°6 - 3 — 27-4 | -338
86°67 134 56°67 80 26°67 26 - 3°33] —28 = 33°33
186°8 132°8 78°8 26 24-8 ae = 29°92 | —- 34
186 85°56 132 55°56 78 25°56 24 = 4:44] -30 = 34:44
185 85 131 55 77 25 23 =- 5 - 31 - 35
184 84°44 130 54°44 76 24°44 22 —- 5°564 - 32 — 35°56
183*2 84 129-2 54 75°2 24 21°2 - 6 — 32°8 | -86
182 83°33 128 53°33 74 23°33 20 — 6°67] -— 34 — 36°67
181-4 127-4 5 73°4 23 19°4 - 7 — 34°6 | - 87
180 82+22 126 52°29 2, 22-22 18 - 7°78) -36 = 37°78
179°6 125°6 5 71°6 22. 17°6 - 8 - 36°4 | - 38
178 81-11 124 51'1l 70 21°11 16 - 8:89} -—88 — 38°89
177°8 123°8 5 69°8 21 158 - 9 - 38:2 | - 89
176 80 122 50 68 20 14 -10 - 40 - 40
174:2 79 120-2 4 66°2 19 12°2 =l1 — 41°80) —41
174 78°89 | 120 48°89 66 18°89 12 - ll-ll}] -4 = 41:11
172°4 8 118°4 64°4 10°4 -12 - 43°60) - 42
172 77°78 118 47°78 64 17°78 10 — 12-22] —-44 = 42-92
170°6 116°6 4 62°6 17 8: -13 — 45°40/ -43
170 76°67 116 46°67 62 16°67 8 - 13:33] - 46 — 43:33
168°8 114°8 4 60°8 16 6°8 -14 — 47:20| -~44
168 75°56 114 45°56 60 15°56 6 ~ 14:44] - 48 — 44°44
167 75 113 45 59 15 5 - 15 - 49 - 45
166 74°44 | 112 44°44 58 14°44 4 - 15°56] -—50 = 45°56
165°2 74 111-2 57°2 3°2 -16 — 50°80| —- 46
73°33 | 110 43°33 56 13°33 2 — 16°67] — 52 = 46°67
163°4 73 109°4 554 13 1*4 - 17 — 52°60) - 47
162 72°22 108 42°22 54 12°22 1 — 17:22] -54 = 47°78
161°6 72 107°6 53°6 12 re) = 17°78} — 54:40} - 48
160 71°11 106 41°11 52 ll-1l J — 0°4 -18 - 56 = 48°89
159°8 71 105°8 51°8 1 -1 - 18:33] - 56°20) -49
9 -2 - 18-89 | - 58 - 50
= 2:2 -19
ee a

FAHRENHEIT

40 30 20 10 0 10 20 30 40 50 60 70 80 GATTI 212
LA CUT LT

TIT
40 2 20 10 0 10 20 30 40 50 60 70 80 %0 100
eee ee See

( 10

\.

GREATLY REDUCED PRICES —
OBJECT-GLASSES MANUFACTURED BY

R. & J. BECK,

68, CORNHILL, LONDON, E.C.

PRICES OF BEST ACHROMATIC OBJECT-GLASSES.

pues Linear magnifying-power, with Seach

a Focal lost res Price. body-tube and eyespieees
ture
about No. 0) No 2 No. 8./No. 4 No. 8,
A Dig Se Os : :
100 | Zinches .. .. 9 : 10 8 10 16 |. 30 |. -40 me
3 inch cae Mave 110° xt
to aides Oe ee } ese eee ie oat
108 | 2 inches To 110:0)\° ‘
104 | 2 inches S 210 0 \ 22 36 67 90 Ti2
106 es incl “ 23 2 2 ° 39 48 90 | 120 150
2 ine 3 2

107 | 2 inch 210 0 \ 72) 112 | 210 | 2801 350
108 | inch. 45 210. O| 100 160] 300} 400 500
109 | +,inch .. 65 4 0O O} 125 | 200) 375 | 500 625
ALO. inch ber. s te igs 5-0 0} 150] 240 | 450 |° 600}, 750
111 Z Inch oes sees Se 15 310 0 200 |, 320 | 600} 800 1000
142) 2 inch un ae a, | $120 410 0}. 250.| 400°} 750 | f000 | 1250
PLB 2 tnd fe OK gO 5 O O}| 4001} 640 | 1200) 1600) 2000 ~
114 |, imm. ev LT BO 5 5 O71 500} 800.) 1500 | 2000 | 2500
115 |: imm. .. .. | 180 | 8 O O| 750 1200] 2250} 3000°| 3750 ~
116 |= imm. .. .. | 180 | 10 O O'| 1000 | 1600 | 3000 | 4000} 5000"
117.| p,inch.. .. .. | 160 | 20 O OQ | 2000 | 3200 | 6090 | 8000 | ro,0¢0

ECONOMIC ACHROMATIC OBJECT-GLASSES,

APPLICABLE TO ALL INSTRUMENTS MADE WITH THE UNIVERSAL SoREW..

Angle
No. Focal length. aper- Price.
ture,
about
ps ES, 7 des
150 | 8 inches 6 1.0 0
| 151 | 2 inches yA oe 8 +-1°0 0
Dip ey Sone c farce aca ie 18 1°50
PS 4) inch a ae) ee ee 1.5 O
V5 42 inchs oe ts 80 15 0
155 1-2 inch oe ie ort | LO 2.5 0
156 a IDCH es eee | TO 310 0
157 | 3; imm. EAR peared Ree 09) 6 0 0

| Maaniryine-PowER,
_| with 6-ineh body and

No, 1.|No. 2. No. 8.

eye-pieces,

250 | 330 | 630
350 | 450 | 800
654} 844 |1500

Revised Catalogue sent on application to
GS, Cornhill.

R. & J. BECK,

Here ti ee
ond OG LAN
b' Oy a
iy a tiga R

Dey! Bess,

JOURN.R.MICR.SOC 1889 P1.X.

Newman lith.

Su

We

soria from the United States.

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eritri

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JAN 20 1903

JOU-BNA Ly epee
GARDEN
OF THE

ROYAL MICROSCOPICAL SOCIETY.

AUGUST 1889.

TRANSACTIONS OF THE SOCIETY.

VII.— Notices of New Perttrichous Infusoria from the Fresh Waters
of the United States.

By Dr. Aurrep OC. Sroxzs.
(Read 8th May, 1889.)
PLATE X.
Epistylis vittata sp. nov., fig. 1.

Bodies elongate-ovate, less than three times as long as broad,
widest centrally, tapering posteriorly, slightly constricted beneath the
peristome ; cuticular surface finely striated transversely, the posterior
one-fifth also longitudinally striate; peristome border broad, not
everted, not revolute, but when expanded slipping backward and in-
vaginating the anterior border of the body as by a broad, somewhat
concave band, both margins of which are usually crenulate ; ciliary
disc convex, prominent; ciliary circles four; nucleus long, band-like,
much curved, often irregularly constricted; pedicle profusely and
dichotomously branched, becoming brown with age ; ultimate divisions
of the foot-stalk about as long as the extended body; zooids many,
often one hundred or more in number ; contracted bodies obovate,
posteriorly annulate in several transverse folds, anteriorly plicate,
the contracted ciliary disc frequently conical or snout-like ; endoplasm
granular, often brownish. Length of bodies 1/120 in.; fully de-
veloped colony 1/5 in. in height, conspicuously visible to the naked
eye. Hab. Fresh water, attached to the shell of Physa.

Epistylis elongata, sp. nov., fig. 2.

Bodies elongate, less than four times as long as broad, widest
centrally, tapering thence posteriorly, the sides of the anterior region
nearly parallel or slightly tapering; cuticular surface very finely

EXPLANATION OF PLATE X.

Fig. 1.—Zpistylis vittata, ! Fig. 6.— Vorticella conosoma.
ue — | sy elongata. | >» I a Conochili.

» o— >» Gutumnalis. » 8.—Opisthostyla globularis,
+ 7 ramosa. » I 3 similis.

” a
» o—Pyxidium nutans.

1889. 2

478 Transactions of the Society.

striate transversely ; peristome border thickened, not revolute, when
expanded slipping back for a short distance about the anterior extremity
of the body, as in Epistylis vittata, but not concave; ciliary disc
prominent, convex and cushion-like ; ciliary circles apparently three ;
nucleus band-like, much and variously curved in the anterior body-
half, often transversely placed ; contractile vesicle spherical, situated far
forward, apparently in the ciliary disc ; endoplasm finely granular ;
pedicle dichotomously and profusely branched, longitudinally striate,
the primary portion about equal in length to an extended body, the
ultimate divisions from one-fourth to one-fifth that length; zooids
numerous ; contracted bodies ovate, often pendent, posteriorly annulate
in three or four folds. Length of extended body 1/240 in.; height
of entire pedicle 1/56 in. Hab. Pond water; attached to rootlets of
Lemna.

Epistylis autumnalis, sp. noy., fig. 3.

Bodies conical-campanulate, three times as long as broad, the
cuticular surface very finely striate transversely ; peristome exceeding
the body in width, everted and revolute; ciliary disc obliquely
elevated; ciliary circles two, the outer wreath projecting almost
horizontally ; nucleus band-like, curved, transversely placed in the
anterior body-half; contractile vesicle single, spherical, anteriorly
located apparently within the ciliary disc; contracted body obovate
or subspherical, posteriorly annulate, and invaginating the extremity
of the foot-stalk; pedicle dichotomously branched, more or less
flexuose, longitudinally striate, the ultimate divisions about one-
third as long as the extended zooids, the main stem about one-half
the length of the entire pedicle, the whole becoming brown with
age. length of extended body 1/300 in.; height of entire pedicle
1/65 in. Hab. Pond water; attached to the rootlets of Lemna, in
the autumn.

Epistylis ramosa, sp. nov., fig. 4.

Bodies elongate-ovate or elongate-subvasiform, less than four times
as long as broad, widest subcentrally, tapermg posteriorly to the
pedicle and anteriorly to a short, subeylindrical, neck-like prolongation,
the frontal border truncate, crenulate; cuticular surface very finely
striate transversely ; peristome narrower than the body centre, neither
revolute nor much everted; ciliary disc obliquely elevated ; ciliary
circles apparently two; pharyngeal passage very capacious, extending
beyond the centre of the body, its walls conspicuously ciliated ; pedicle
finely striate longitudinally, profusely and dichotomously branching,
the divisions in mature colonies forking from eighteen to twenty times,
the ultimate branches about one-half the length of an extended body,
the entire foot-stalk becoming brown with age; contracted zooids -
elongate-obovate, nodding, invaginating the summit of the pedicle and
posteriorly annulate, bearing anteriorly a short, longitudinally plicate,
snout-like projection, the frontal border crenulate; nucleus band-like,

New Peritrichous Infusoria, de. By Dr. A. C. Stokes. 479

broad, curved, transversely placed in the anterior body-half. Length
of body 1/225 in.; colony often measuring 1/15 in. in height. Hab.
Pond water, in the autumn.

Pyaidium nutans, sp. nov., fig. 5.

Body elongate-subfusiform, about twice as long as broad, some-
what gibbous, widest centrally, tapering posteriorly to the pedicle,
slightly constricted beneath the truncate, finely crenulate peristome
border; cuticular surface smooth; ciliary disc conspicuously and
obliquely exserted; ciliary circles two, the second wreath extending
almost horizontally ; vestibulum capacious, extending to near the
body centre, strongly ciliate, a long, curved, and conspicuous vesti-
bular bristle present; pedicle short, about one-fifth as long as the
body, variously and irregularly undulate; contracted body obovate,
suddenly nodding, the posterior region inconspicuously invaginating
the anterior termination of the pedicle, and variously and irregularly
annulate, with an anterior snout-like projection. Length of body
1/450 in. Hab. Pond water; attached to the rootlets of floating
aquatic plants. Solitary.

Vorticella conosoma, sp. nov., fig. 6.

Body conical, soft and flexible, transversely striate, about four
times as long as broad, widest at the frontal margin, tapering thence
to near the attachment to the pedicle where it is continued as a
minute, subeylindrical prolongation, frequently showing at the begin-
ning of the posterior third a slight transverse constriction ; peristome
border everted, not revolute ; cilia short ; nucleus transversely placed
in the anterior body-half, short, broadly band-like, and much curved,
in certain positions of the body apparently ovate; pedicle filiform,
from two to three times as long as the body, the muscular thread
distinct. Length of body 1/375 in. Hab. Attached to the gelati-
nous tubules of Conochilus volvow.

This interesting form was first observed attached to the same
colonies of Conochilus which bore the Vorticella Conochili, to be next
referred to, but in much less abundance, not more than two having
been noted on the same cluster of Rotifers. Although the muscular
thread is distinctly developed it seems seldom to exercise its contractile

ower.
2 The body when contracted becomes elongate-obovate, the trans-
yerse constriction appears more distinctly marked, and the region in
advance settles back toa slight extent, and inconspicuously invaginates
this encircling depression in one or two folds.

Vorticella Conochili, sp. nov., fig. 7.

Body conical-campanulate, soft and changeable in shape. usually
somewhat gibbous, one and one-half times as long as broad; trans-
versely striate ; peristome slightly narrower than the body centre, the

2u 2

480 . Transactions of the Soctety.

border revolute ; ciliary disc somewhat oblique, not elevated ; posterior
extremity attached to the pedicle through the intermedium of a small
button-like projection ; pedicle filiform, from seven to eight times as
long as the body, only the anterior portion contracting when the foot-
stalk is thrown into its small, irregular undulations rather than spiral
folds ; contracted body obovate, the button-like extremity invaginate
within the body; endoplasm colourless ; nucleus band-like, much curved,
often forming an almost complete circle, situated in the anterior body-
half. Length of body 1/750 in. Hab. Attached to the gelatinous
tubules of Conochilus volvox.

A gathering made in the early part of the month of November
contained a large number of the beautiful free-swimming colonial
Rotifers Conochilus volvow, and every colony of the many examined
bore from three to six individuals of this parasite, or perhaps more
properly, commensal Vorticella, the pedicle being attached to the
gelatinous material which partially inclosed the colony.

Vorticella molesta, sp. nov.

Body conical-campanulate, less than twice as long as broad, soft
and changeable in shape, slightly constricted beneath the peristome,
the cuticular surface very finely striate transversely ; peristome ex-
ceeding the body centre in width, revolute; pedicle stout, from five to
six times as long as the body, the muscular thread becoming rigid and
deeply chestnut brown in colour, presumably with age; contracted
body broadly obovate, the extremity of the pedicle invaginate. Length
of body, 1/575 in. Hab. Attached to the shell of an aquatic snail,
probably a young Lymmnea. Social. |

The muscular thread of some species of Vorézcella, notably of
V. picta, has been observed to contain many minute scarlet corpuscles,
and similar coloured particles have been noticed within or adherent to
the contractile filament of other forms; but in the present species
the coloration is a deep chestnut brown extending evenly from the
point of attachment to the supporting object nearly up to the posterior
extremity of the body, gradually fading until the merest trace is
visible at the extreme anterior termination. No pedicle has been seen
with the colour reaching entirely up to the posterior border of the
zooid. The tint also extends to the sheath, but in a much less
marked degree. Those pedicles thus affected had lost most of their
contractile power, only the proximal, almost colourless portion
retaining its ability to coil, an ability exercised imperfectly and
apparently with some difficulty. The remaining or tinted region
presents the aspect of a slightly undulate, rigid thread, this extended
and stiff condition remaining after the separation of the body and the
subsequent death of the muscle. The Vorticellz were infesting the
shell of the water snail to such an extent as to impede the progress of
the mollusc, and to give it the appearance of being surrounded by a
whitish fungoid growth.

The transverse cuticular strie are very fine, requiring some
manipulation of the mirror to display them distinctly.

New Peritrichous Infusoria, &de. By Dr. A.C. Stokes. 481

Opisthostyla globularis, sp. nov., fig. 8.

Body subglobose, soft and somewhat changeable in shape, often
slightly gibbous, the length but little greater than the breadth ;
cuticular surface transversely striate; peristome less than the body
centre in width, the border revolute; ciliary disc not elevated ;
pedicle slightly exceeding the body in length. Length of body 1/000
in. Hab. Pond water, attached to Hydrodictyon utriculatum.

Opisthostyla similis, sp. nov., fig. 9.

Body subvasiform, somewhat changeable in shape posteriorly,
less than twice as long as broad, somewhat gibbous, slightly con-
stricted beneath the revolute peristome border; the posterior region
bearing two rounded, transverse annulations, the anterior being the
larger, the posterior extremity often apparently united to the pedicle
through the intermedium of a disc-like appendage; cuticular surface
strongly striate transversely ; ciliary disc slightly and obliquely
elevated ; pedicle in length somewhat exceeding that of the body, the
distal extremity scarcely curved ; contracted body obovate, slightly
invaginating the extremity of the pedicle. Length of body 1/1125
in. Hab. Pond water, attached to the rootlets of various floating
aquatic plants.

This form is readily recognizable from those previously described,
by the presence of the annular body-enlargements, and the slight
distal curvature of the pedicle. The backward springing of the
contracted zooid is that characteristic of the genus, but individuals are
at times met with in which the larger, more anterior annulation lacks
the usual convex borders, being replaced by flattened, almost perpen-
dicular margins, so that this portion of the body more nearly resembles
a short cylindrical constriction. In these individuals the posterior
ring is frequently inclosed within that part of the posterior region
which invaginates the extremity of the pedicle when the zooid is
contracted, the animalcule in these cases appearing not to have
extended the body entirely so as to free the pedicle wholly from its
invagination, the posterior annulation thus becoming obscure or
obsolete.

Halsis (adovs, leaping), gen. nov.

Animalcules free-swimming, ovate, persistent in form, peritrichous ;
equatorial ciliary girdles two or more; several long, non-vibratile,
widely separated setee projecting from the posterior body region ; no
supplementary springing hairs; oral aperture terminal, the adoral
cilia seeming to form a simple spiral wreath. Inhabiting fresh water.

Halsis furcata, sp. nov.

Body ovate, less than twice as long as broad, the posterior
border rounded, the anterior convexly truncate; oral aperture
apparently eccentric, surrounded by a short, snout-like projection

482 Transactions of the Society.

followed by a short but conspicuous, curved pharyngeal passage ;
equatorial cilia not numerous, forming three girdles, those of the
posterior circlet furcate ; caudal hairs long, flexible, distally curved,
from six to eight in number, widely separated and arising from the
cuticular surface at some distance from the posterior border ; con-
tractile vesicle apparently single, spherical], in the anterior body region
near one lateral border; nucleus not observed. Movements rotatory
on the longitudinal axis, often rapidly backward, with sudden back-
ward leaps. Length of body 1/1125 in. Hab. Standing pond
water.

. This is undoubtedly a member of the Halteriide of Claparede and
Lachmann, but it is refused admission to any described genus by the
presence of the setose caudal hairs springing from the posterior body
region. These are subequal to the body in length, flexible but non-
vibratile, trailing behind when the animalcule is swimming. ‘The
creature, however, possesses the ability to throw them forward, and it
is probable that the sudden backward leaps and quick turns so often
made, are accomplished by the action of these posterior sete. The
furcate condition of the cilia composing the posterior equatorial
circlet is worthy of notice. ‘The adoral cilia appear to be fimbriated.*

* The original drawing of this animalcule has been mislaid or lost, so that a
figure canuot be given.

JOURN.R.MICR.SOC 1889. Pl. X1.

E.C. Knight, ith. West, Newman &Co,imp,

Horaminifera fr om. the London Clay.

x 20

( 483 -)

VIII.—Additional Note on the Foraminifera of the London Clay
exposed in the Drainage Works, Piccadilly, London, in 1885.

By C. Davies Saerpory, F.G.S., and Freprerick CHapmay.
(Read 8th May, 1889.)
Prats XI.

In a former paper on this subject, published in the Journal for
1886, eighty-eight well-marked varieties of Foraminifera were
described from the London Clay of Piccadilly, London, thus bringing
up the total number of forms recorded from the formation to 136.
In the present communication we briefly describe twenty-eight forms,
twenty-one of which are new to the London Clay. The fact that one
of our former “species” required further consideration and examination
led us to manipulate the remainder of samples of the clay collected in
1885, and carefully re-examine our earlier washings, in the hope of
finding more specimens worth attention. In this we were successful,
and are now enabled to amend our views upon the form previously
described as Lagena oviformis, and also to make some interesting
additions to our knowledge of the London Clay foraminiferal fauna.
All the specimens here described were obtained from the “ black-bed ”
referred to at p. 740 of our former paper.

EXPLANATION OF PLATE XI.

Fig. 1.—Wiliolina trigonula (Lamarck).
oA eo ae venusta (Karrer).
5 4, 5.—Cornuspira involvens, Reuss.
: ss carinata (Costa),
9» 7.—Ammodiscus incertus (d’Orbigny).
5 8.—Haplophragmium agglutinans (d’Orbigny).
» 9—Thurammina papillata Brady.
», 10.—Textularia agylutinans, var. porrecta Brady.
», 11.—Clavulina parisiensis @ Orbiguy.
5, 12.—Chilostomella ovoidea Reuss.

3 La: 9 oviformis Sherborn and Chapman.

», 14.—WNodosaria simplex Silvestri.

pelios 3 radicula, var. annulata Terq. and Berth.
37 LG. 55 fC var. ambigua Neugeboren.

ry slibelliee © ep longiscata d’Orbigny. '

ke! = sp.

5, 20. eS oligotoma Reuss.

Spear Ss5 catenulata Brady.

A obliquata (Batsch).

24,.—Dentulina suleata (Nilsson).
» 25.—Vaginulina sp. (? deformed).

» 26. a legumen (Linné), var.
» 27.—Marginulina attenuats Neugeboren.
» 28 -. costata (Batsch).

5, 29.—Pullenia quinqueloba (Reuss).
», 30-32.—Pulvinulina elegans (d’Orbigny).
», 33.—Discorbina rugosa (d’Orbigny).
»5 34.—Anomalina grosserugosa (Giimbel).
All figures are x 20.
(‘The specimens will be deposited in the British Museum.)

484 Transactions of the Society.

Miiorina Williamson [1858].

Miliolina trigonula (Lamarck), plate XI. fig. 1. Miltolites tri-
gonula Lamarck, Ann. Muséum, vy. (1804) p. 351, No.8; Triloculina
trigonula (Lam.) d’Orbigny, Ann. Sci. Nat., vii. (1826) p. 229, No. 1,
plate xvi. figs. 5-9; Modéle, No. 93.—Common, but very small; the
specimen figured is large in comparison with the others found in the
ey Clay. Previously recorded from Sheppey and Haverstock

ull.

Miliolina venusta (Karrer), plate XI. figs. 2,3. Quinqueloculina
venusta Karrer, Sitz. k. Ak. Wiss. Wien, lvii. (1868) p. 147, plate ii.
fig. 6.—Four individuals. New to the London Clay. Dr. Karrer’s
specimens came from the Miocene of Kostej.

Cornuspira Schultze [1854].

Cornuspira involvens (Reuss), plate XI. figs. 4,5. Operculina
involvens Reuss, Denkschr. k. Ak. Wiss. Wien, i. (1849) p. 370, plate
xly. fig. 20; Cornuspira involvens Reuss, Sitz. k. Ak. Wiss. Wien,
xlyiii. 1863, p. 39, plate i. fig. 2—One specimen found by Mr. A.
M. Davies in a sample of clay given him by one of us. Previously
recorded from the London Clay of Sheppey by Mr. Shrubsole.

Cornuspira carinata (Costa), plate XI. fig. 6. Operculina cari-
nata Costa, Atti Acc. Pontan., vil. (1856) p. 209, plate xvi. fig. 15 a, b.
-—One individual, which, though damaged, still preserves its characters.
This specimen almost exactly corresponds to the form figured by
Reuss, from the Septarienthon of Offenbach, as C. Bornemanni, Sitz.
k. Ak. Wiss. Wien, xlviii. 1863, p. 39, plate i. fig. 3, which is the
same form as C. carinata (Costa). New to the London Clay.

Hapitopuracmium Reuss [1860].

Haplophragmium agglutinans (d’Orbigny), plate XI. fig. 8.
Spirolina agglutinans d’Orbigny, Foram. Foss. Vienne, 1846, p. 137,
plate vii. figs. 10-12.—One example. New to London Clay.

THuramurna Brady [1879].

Thurammina papillata Brady, plate XI. fig. 9. Brady, Quart.
Journ. Mier, Sci, xix. (1879) p. 45, plate v. figs. 4-8.—Not previously
recorded from ‘'ertiary beds. Dr. Haeusler* has described numerous
varieties from the Jurassic of Switzerland, and Dr. Uhlig + from beds
of the same horizon in Austria and Wurtemberg.

Amwmopiscus Reuss [1861].

Ammodiseus incertus (d’Orbigny), plate XI. fig. 7. Opereulina
incerta VOrbigny, Foram. Cuba, 1839, p. 71, pl. vi. figs. 16, 17.—

* Neues Jahrb., 1883 (1), p. 60; Annals Mag. Nat. Hist. 5, xi. 1883, p. 262;
Quart. Journ. Geol. Soc., xxxix. 1883, p. 27; Neues Jahrb. BB iy. (1), 1885, p. 30.
+ Neues Jahrb., 1882, p. 152.

On Foraminifera, &c. By C. D. Sherborn & F. Chapman. 485

One specimen. Previously recorded from four localities of the London
Clay. (See the former paper, p. 760, Trochammina.)

Textuparia Defrance [1824].

Textularia agglutinans dOrbigny, var., plate XI. fig. 10.
DOrbigny, Foram. Cuba, 1839, p. 136, plate i. figs. 17, 18, 82-34.
—This variety of 7. agglutinans, with its rounded chambers and
subeylindrical form, is comparable with Brady’s var. porrecta (Report,
‘Challenger, 1884, p. 364, plate xlii. fig. 4).

Cravutina d’Orbigny [1826].

Clavulina parisiensis, dOrbigny, plate XI. fig. 11. D’Orbigny,
Ann. Sci. Nat., vii. (1826) p. 268, No. 3; Modele, No. 66.—The
specimen mentioned at p. 743 of our former paper is here figured, and
is the only example found which shows the characteristic triangular
shape of the early chambers. Dr. Brady mentions its occurrence in
abundance in the London Clay near Clapham Common.*

CHILOSTOMELLA Reuss [1849].

Chilostomella ovoidea Reuss, plate XI. fig. 12. Reuss, Denkschr.
k. Ak. Wiss. Wien, i. (1849) p. 380, plate xlviii. fig. 12 a-e——One .
specimen. - New to the London Clay.

Chilostomella oviformis Sherborn and Chapman, plate XI. fig. 13.
Lagena (Obliquina) oviformis, Sherborn and Chapman, Journ. R.
Micros. Soc., ser. 2, vi. 1886, p. 745, plate xiv. figs. 19 a-d.—The
erroneous reference of this form to Lagena was principally due to the
fact that the interiors of the specimens described were occupied by sand.
We have now been so fortunate as to secure a few more specimens
which have the internal structure preserved, and we have no hesitation
in referring the form to Chilostomella. This is also the opinion of
Dr. Brady who has kindly examined our specimens. The interest of
this form of Chilostomella lies in the fact that the successive external
chamber envelopes the whole of the previous structure, and thus
presents what appears to be a test of a single chamber. We givea
dotted outline of the internal structure restored from several partially
perfect individuals, and have nothing to add to the original description
of the exterior.

Noposaria Lamarck [1816].

Nodosaria simplex Silvestri, plate XI. fig. 14. Silvestri, Atti
Ace. Gioenia Sci. Nat., vii. (1872) p. 95, plate x1. figs. 268-72.—One
small individual. New to the London Clay.

Nodosaria radicula, var. annulata Terquem and Berthelin,
plate XI. fig. 15. Glandulina annulata Terg. & Berth., Mém. Soe.
Géol. France, sér. 2, x. (1875) Mém. 3, p. 22, plate i. fig. 25.—One
example. New to the London Clay.

* Report ‘ Challenger,’ 1884, p. 395.

486 Transactions of the Society.

Nodosaria radicula, var. ambigua Neugeboren, plate XI. fig. 16.
Nodosaria ambigua Neugeboren, Denkschr. k. Ak. Wiss. Wien, xil.
(1856) p. 71, plate i. figs. 13-16.—Two or three examples. Not
previously recorded from the London Clay.

Nodosaria longiscata d’Orbigny, plate XI. figs. 17, 18. D’Orbigny,
Foram. Foss. Vienne, 1846, p. 32, plate 1. figs. 10, 11. Nodosaria
arundinea Schwager, Sherborn and Chapman, Journ. R. Micros. Soc.,
ser. 2, vi. (1886) p. 747, plate xiv. figs. 28, 29. Nodosaria longiscata
dOrbigny, Brady, Quart. Journ. Geol Soc., xliv. 1888, p. 6.—Since the
critical remarks, in our former paper, on d’Orbigny’s figures, Dr. Brady
has kindly shown us some of the original specimens examined by
dOrbigny, sent to him by Dr. Karrer, of Vienna. We have there-
fore had the opportunity of verifying Dr. Brady’s conclusion that
d’Orbigny, although he figured only the “sugar-loaf” form, included
the whole of these smooth, slender, reed-like Nodosariz in one
“species.” Weare much indebted to Dr. Karrer and Dr. Brady for
the examination of this form, as the varying conditions of the chambers
have unfortunately given rise to almost endless specific naming.
Fig. 18 is the particular variety which was named by Terquem
N. sublongiscata* ; it shows four chambers, and is unusually perfect
compared with the specimens generally found in the London Clay.
Fig. 17 is an interesting example, showing the initial chambers.

Nodosaria sp., plate XI. fig. 19—The internal cast of two
chambers of a Nodosarian, the upper of which shows fine longitudinal
strie.

Nodosaria oligotoma Reuss, plate XI. fig. 20. Reuss, in Geinitz,
Paleontographica, xx. part 1 (1872) p. 135, plate xxxii. fig. 16.—
One of the numerous varieties of Linné’s Nodosaria raphanus, figured.
by Reuss as NV. oligotoma. One specimen. New to the London Clay.

Nodosaria catenulata Brady, plate XI. figs. 21, 22. Brady,
Report, ‘ Challenger, 1884, p. 515, plate lxiii. figs. 32-34.—The two
fragments figured are all that were found. New to the London Clay.

Nodosaria obliquata (Batsch), plate XI. fig. 28. Nautilus
obliquatus Batsch, Sechs Kupfertafeln Conch. Seesandes, 1791, plate 11.
figs. 5 a, b,c.—Two fragments only found. New to the London Clay.

Dentatina d’Orbigny [1826].

Dentalina sulcata (Nilsson), plate XI. fig. 24. Nodosaria sul-
cata Nilsson, Petrif. Suecana, pt. 1, 1827, p. 33, plate ix. fig. 19.—
Only the fragment figured was found. Not previously recorded from
the London Clay.

Vaernuuina d’Orbigny [1826].

Vaginulina leqgumen (Linné), var., plate XI. fig. 26. Nautilus
legqumen Linné, Syst. Nat., ed. 10, 1758, p. 711, No. 248.—This
elegant little specimen we regard as a variety of Linné’s well-charac-
terized “ species.”

* Mém. Ac. Imp. Metz, xlii. (1862), p. 487, figs. a, b, in text.

On Foraminifera, de. By C. D. Sherborn & F. Chapman. 487

Vaginulina sp. plate XI. fig. 25.—A small, compressed, and
deformed (?) Nodosarian of doubtful relationship.

Marainuxina d’Orbigny [1826].

Marginulina attenuata Neugeboren, plate XI. fig. 27. Neuge-
boren, Verh. Mitth. Siebenbiirgen Ver. Nat., Jahrg. ii. (1851) p. 121,
plate iv. figs. 3-6.—The name MM. attenuata may reasonably be made
to include the whole of the unornamented elongated Marginuline
figured by Neugeboren on his plate iv. Indeed, in his later paper
(ibid., Jahrg. xi. 1860, p. 55) he has referred three of his former
species (M. Orbignyana, M. Reussiana, and M. irregularis) to M.
attenuata, thus showing that he did not then agree with the specific
value of gradational varieties. Our specimen is the only one found.
Not previously noted from the London Clay.

Marginulina costata (Batsch), plate XI. fig. 28. Nautilus
(Orthoceras) costatus, Batsch, Sechs Kupfertafeln Conch. Seesandes,
1791, p. 2, plate i. figs. 1 a-g.—Only this specimen found. New to
the London Clay.

PuxentA Parker and Jones [1862].

Pullenia quinqueloba (Reuss), plate XI. fig. 29. Nonionina
quinqueloba Reuss, Zeitschr. Deutsch. Geol. Ges., iii. (1851) p. 47,
plate v. figs 31 a, b—Only one specimen of this slightly compressed
form has been found; it shows, however, all the characteristics of
Reuss’s variety. New to the London Clay.

Discorpina Parker and Jones [1862].

Discorbina rugosa (d’Orbigny), plate XI. fig. 33. Rosalina
rugosa dOrbigny, Foram. Amér. Mérid., 1839, p. 42, plate ii. figs.
12-14.—One specimen, which has lost the final chamber, occurs in
the Piccadilly washings. New to the London Clay.

Anomatina d’Orbigny [1826].

Anomalina grosserugosa (Giimbel), plate XI. fig. 834. Trunca-
tulina grosserugosa Giimbel, Abh. k.-bay. Ak. Wiss., x. (1868) p. 660,
plate un. fig. 104 a, b; Anomalina sp. Sherborn and Chapman, Journ.
R. Micros. Soc., ser. 2, vi. (1886) p. 757, fig. 156.—Having found
more specimens of this form, we are able to assign it definitely to
Giimbel’s “species,” according to the suggestion expressed in our
former paper.

Punyinuuina Parker and Jones [1862].

Pulvinulina elegans (d’Orbigny), plate XI. figs. 30-32. Rotalia
(Turbinulina) elegans @Orbigny, Ann. Sci. Nat., vii. (1826) p. 276,
No. 54; Pulvinulina elegans (d’Orbigny), Brady, Report ‘ Challenger,’

488 Transactions of the Society.

ix. (1884) p. 699, plate cv. figs. 3 a, b, c—Numerous small specimens
of this form, which, according to Parker, Jones, and Brady,* passes
insensibly into P. Partschiana d’Orbigny, occur in our last washings.
It has previously been recorded by Professors Rupert Jones and
Parker from the London Clay of the bed of the Thames at Chelsea,
and from Wimbledon.

* The Pulvinulina elegans group, including P. Partschiana, were fully treated of by
Parker and Jones in 1865, Phil. Trans., clv. pp. 392, 393, 397, pl. xvi. figs. 44-46.

( 489 )

SUMMARY

OF CURRENT RESEARCHES RELATING TO

ZOq LOG Ys AND. BOT ANY
(principally Invertebrata and Cryptogamia), -

MICROSCOPY, &c.,
INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.*

ZOOLOGY.
A. VERTEBRATA :—Embryology, Histology, and General.
a. Embryology.t+

Uterus and Embryo.{—Mr. C. 8. Minot has investigated the relations
of the uterus and embryo in the Rabbit and in Man. In the resting
uterus of the rabbit there are six longitudinal folds; the ovum attaches
itself on or between the two folds nearest the mesentery, and the placenta
is then developed ; the two adjacent lateral folds form a cushion (“ peri-
placenta”) about the placenta, but the two folds opposite the mesentery are
flattened out by the stretching of the walls to form the swelling to contain
the embryo; they constitute the ob-placenta. The entire epithelium
lining the uterine swelling degenerates, and this degeneration affects the
glands also. The connective tissue increases by hyperplasia in the peri-
placenta and to a greater degree in the placenta, and is transformed for
the most part into uninucleate perivascular decidual cells, but also in
part into large multinucleate cells. In the placental region the glands
are preserved as irregular anastomosing rows of coarse granular matter ;
below the glands is a zone containing wide vessels and large multi-
nucleate cells.

The embryo is attached at first to the surface of the placenta only
by the ectoderm, with which the mesoderm soon becomes connected. So
soon as the ccelomatic fissure appears we can speak of a foetal chorion
adhering to the placenta. When the allantois grows out it forms the
stalk of connection between the embryo and the placental chorion.
Outgrowths of the chorion penetrate the glandular layer of the placenta.
The ccelom of the embryo does not extend to the edge of the placenta
next the peri-placenta, but the mesoderm does and is covered by
ectoderm.

In the ob-placenta degeneration and resorption affect only the
surface epithelium and the upper part of the glands; the deep portions

* The Society are not intended to be denoted by the editorial “ we,” and they do
not hold themselves responsible for the views of the authors of the papers noted,
nor for any claim to novelty or otherwise made by them. The object of this part of
the Journal is to present a summary of the papers as actually published, and to
describe and illustrate Instruments, Apparatus, &c., which are either new or have
not been previously described in this country.

+ This section includes not only papers relating to Embryology properly so called,
but also those dealing with Evolution, Development, and Reproduction, and allied
subjects. t Journal of Morphology, ii. (1889) pp. 341-462 (4 pls.).

490 - SUMMARY OF CURRENT RESEARCHES RELATING TO

remain as a series of shallow cups, having been stretched transversely
by the expansion of the ob-placenta. The epithelium of the cups unites
into a new continuous layer, the glands grow up into follicles and are
again stretched out by the expansion of the walls. The ectoderm which
attaches the embryo disappears from the surface of the placenta during
the eleventh day ; the vascular connective tissue of the allantois probably
grows by forming true villi into the placenta, and so comes close to the
maternal circulation.

The observations on the human subject are, as may be supposed,
somewhat scattered. ‘The author finds that the umbilical cord is not
covered by the amnion, but by an extension of the foetal epidermis.
Its coelomatic cavity is completely obliterated during the third month,
and a little later the stalk of the yolk-sac is resorbed. The allantoic
epithelium persists as a tube or cord of cells for a long period. The
blood-vessels have specialized walls derived from the surrounding
mesoderm, but have no true adventitia. Connective-tissue fibres begin
to develope during the third month. The amnion is covered by a single
layer of ectodermal cells, which are connected by conspicuous inter-
cellular bridges; it- has no true stomata. The chorion consists of two
layers, mesoderm and ectoderm, both of which are present over all parts
of the chorion during the entire period of pregnancy. The mesoderm
has at first a dense colourable matrix, with cells, which colour very
slightly. During the second month the matrix loses its colouring pro-
perty, and subsequently the cells acquire a greater affinity for colouring
matters. The matrix assumes a fibrous appearance, and in one region
the mesoderm is differentiated into an outer fibrillar layer and an inner
and thicker stroma-layer. During the first month the ectoderm divides
into an outer dense protoplasmic layer and an inner less dense cellular
layer. In the later stages of pregnancy the whole ectoderm of the
smooth chorion acquires the character of the cellular layer, except near
the margin of the placenta. The villi are at first of awkward and
irregular form, but their branching gradually becomes more regular, and
the twigs acquire a slender and more uniform shape.

The menstruating uterus is characterized by hyperemia, by hyper-
plasia of the connective tissue of the mucosa, and by hypertrophy of
the uterine glands; the upper fourth of the mucosa is loosened and
breaks off, but there are no decidual cells. The changes of the uterus
during menstruation and gest.tion are homologous, the menstrual cycle
being prolonged and modified by pregnancy ; hence it is that conception
takes place only at the menstrual period, for the ovum can only modify
the menstrual change, not initiate the formation of a decidua. No
satisfactory explanation of the origin of the amnion has yet been
offered. The placenta is an organ of the chorion, but we possess no
positive information as to how it performs its nutrient functions.

Fecundation and Segmentation of Ova of Rats.*—Professor A.
Tafani has observed four stages in the maturation of non-fertilized
ova of rats. In some the maturation-spindle extends under the surface,
while in others it is directed towards a point of this surface, which it
raises up. In some one, and in others two polar globules may be
seen to be expelled. Fecundation takes place when the female pro-
nucleus is on the point of being formed. Not more than one spermatozoon

* Arch, Ital. Biol., xi. (1889) pp. 112-7.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 491

has been seen to come into contact with the egg; its head, which is at
first homogeneous, soon becomes resolved into a small thread formed of
chromatic granules which are connected with one another by filaments,
just as in the case of Ascaris megalocephala, as described by Van
Beneden. The mode of union of the two pronuclei is carefully
described. The segmentation-nucleus is comparatively large. The first
plane of segmentation passes through one of the meridians of the egg,
and the first two blastomeres are exactly equal and similar; it will be
remembered that this is not the case in the Rabbit. When there are
eight blastomeres they are all equal, but exhibit a tendency to become
arranged in two distinct groups. When there are twelve blastomeres
four are larger than the rest.

Reproduction and Development of Teleostean Fishes.*—Mr. J. T.
Cunningham gives an account of his observations on the ova of Teleostean
fishes, made at the new Marine Biological Laboratory at Plymouth. The
Common Sole was found to spawn in March, April, and May; the ovum
after extrusion is of considerable size, about 1:5 mm. in diameter, It
is distinguished by having an immense number of oil-globules of very
small size; these are arranged in groups of irregular shape ; another
characteristic is that the yolk is not perfectly continuous and homo-
geneous, but coextensive with the blastoderm there is a single superficial
layer of separate yolk-masses ; this layer extends with the blastoderm,
so that when the latter has enveloped the yolk the layer of yolk-segments
also envelopes it completely, forming a superficial layer over the whole
surface of the yolk. These peculiarities enable the sole’s egg to be
easily recognized when taken on the open sea in the tow-net. Mullus
and Solea are the only genera whose ova have undoubtedly the peripheral
layer of yolk-segments. It is interesting to notice that these ova present
a condition of the yolk intermediate between that characteristic of non-
pelagic ova and that seen in typical pelagic ova. It is possible that the
peculiar character of the ovum of Solea indicates that there is no close
affinity between this genus and Pleuronectes.

After describing a number of ova and his experiments with them,
Mr. Cunningham propounds a hypothesis concerning oil-globules in
pelagic teleostean ova. He finds that whenever the adult has a large
quantity of oil in its tissues, the ova possess one or more oil-globules in
the yolk. It is probable that the excess of oil in the tissues of the
parents extends into the ovum, and during the developmeut of the
_ latter supplies the embryo with an abundance of fat which is necessary
to its constitution. The cause of many ova which are provided with oil
globules having a greater specific gravity than those that are without
them must be explained by. the greater density of their protoplasin
and yolk.

In conclusion, there is a note on the development of the vascular
system and ccelom in pelagic ova of Teleostei. In a great many the
heart, at the time of hatching, consists of a tube which opens posteriorly
out of a wide space between the yolk, while the heart itself is surrounded
by another cavity separated from the just mentioned space by a thin
membrane ; the cavity which communicates with the heart exists, at an
earlier stage, as a.space between the epiblast of the anterior part of the
yolk-sac and the periblast; traced back it is found to be nothing more

* Journal Marine Biol. Assoc., i. (1889) pp. 10-54 (6 pls.).

4992, SUMMARY OF CURRENT RESEARCHES RELATING TO

nor less than the segmentation cavity. The space surrounding the heart
is a portion of the true celom. The heart is produced by the formation
of the central mesoblastic cells into a tube which, as soon as it has a
lumen, communicates with the space between the ventral epiblastic body-
wall and the periblast. The cavity in which it is contained is due
to a splitting of the mesoblast.

The interesting morphological peculiarity about the venous sinus
in the Teleostean embryo is that it is the persistent segmentation cavity.
This may partially disappear owing to the contact of its walls, but it is
not obliterated by the growth of the mesoblast, so that, when the sinus
venosus appears, it is not as a cavity or system of veins entirely sur-
rounded by splanchnic mesoblast, but is the old segmentation cavity
between the epiblastic ventral wall of the yolk-sac and the periblast.
At a later stage, no doubt, the sinus venosus acquires mesoblastic walls
all round it, but this is not till the yolk has been absorbed.

8. Histology.*

Vital Processes in Living Cells.;—Prof. C. Frommann has made a
study of the vital processes in living cells. He commences with an
account of ripe unfertilized and fertilized ova of Strongylocentrotus lividus.
The granules found in the protoplasm are connected partly by very fine
and partly by somewhat coarse and short filaments. The processes
between the granules lead to the formation of extremely fine or some-
what goarser plexuses. The radiate marking which is seen in the
periphery of some eggs is due partly to rather long fine filaments,
which are beset with separate granules or with small spindle-shaped
nodules, and partly by somewhat coarser indistinctly granulated cords
which are connected by processes with their neighbours ; they sometimes
take a zigzag course.

All the formed parts of the egg undergo a constant change of form
and size as well as some alteration in their refractive power ; they fuse
with one another or divide into two or more fragments; they disappear,
while others are freshly formed; and all these processes occur so
rapidly that it is quite impossible to figure all the successive images that
are presented. These alterations may, moreover, occur in the most varied
manner. Coarser filaments may break up into distinct granules which
separate from or unite with one another; others become indistinctly
granulated or disappear altogether. These processes are often preceded
by a division of the filaments into two cr more pieces, which may under-
go various kinds of changes. Changes in form may accompany alterations
in the characters of the filaments, and they may become bent, hoop-
shaped, or united by bonds with their neighbours. Coarser granules
exhibit corresponding structures.

The same kind of changes in the yolk-substance are seen in fertilized
as well as in unfertilized egos, and there can be no doubt that, so far as
its vital changes are concerned, the yolk-mass completely corresponds to
the protoplasm of other cells.

The rounded or oval homogeneous egg-nucleus has a boundary which
alters in character; there is often a delicate, pale, and unbroken
contour which may yield to one which is delicately granular or

* This section is limited to papers relating to Cells and Fibres.
+ Jenaische Zeitschr. f. Naturwiss , xxiii. (1889) pp. 389-412 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 493

filamentous, and which may project into the nucleus and give its
boundaries an irregular appearance. After treatment with 0-2 per cent.
chromic acid the nucleus generally retains sharp and refractive contours,
while at the same time the nucleolus becomes distinctly apparent.

The much discussed question of the radiate figures in the fertilized
egg is next considered. The author does not find that they exhibit the
regularity which we should be led to expect from the figures and de-
scriptions of O. Hertwig, Fol, and Flemming; as in the other parts of
the cell-body, there are changes in these parts. The rays as well as
their constituent parts continually alter their form and character, dis-
appear, and are again built up; these changes are described in some
detail.

In embryos with from twelve to sixteen and more cells the spaces
between the separate cells are generally very slight; in these granules
may be detected, which may possibly be cell-bridges which appear as
granules in consequence of their shortness. When the intercellular
spaces are somewhat wider there are some indications of filaments.

The changes which take place in the network of the grey substance
of the brain of Torpedo marmorata and Raja asterias, and in the gan-
glionic cells of the Torpedo, are next considered. The changes which
take place in the stroma of the ganglionic cells have the same character
as those which occur in the grey substance—and but for their being
slower—as what are seen in the eggs of Strongylocentrotus lividus. They
also correspond in their morphological relations with what he. been
observed in the blood-corpuscles of Invertebrates, the network of the
tentacles of Hydra, and the living cartilage-cells of the rabbit. In the
leucocytes of the frog not only do the nuclei disappear, and be again
formed from protoplasmic parts, but changes may take place in the
granular and filamentar parts of the cell-body without any new formation
of nuciei. Similar examples may be cited from many plants.

New Formation of Cells.*—Dr. B. Morpurgo finds that new cella
are formed by indirect fission, even during acute inanition of the
organism. Karyokinetic figures are found both in growing organs and
in the adult organs of animals that have died of hunger, and, therefore,
in organs where they give signs of a formative process as well as where
they represent cellular regeneration. Indirect fission, under whatever
conditions produced, becomes less active when there is an inanition of
the organism. The numerical diminution of mitoses is relatively less
in slightly differentiated glandular cells and in investing epithelia than
in highly differentiated glands; of these latter we may say that the
process of karyokinesis is almost wholly limited to the period of their
more active growth. Of the differentiated organs, the gonads alone ex-
hibited a process of very active karyokinesis during the inanition of the
organism. This shows that these organs are highly individualized even
in animals which are high in the zoological scale, and that they are able
to demand of other organs the sacrifice of a richly nutrient material.

Relation between Cell-body and Nucleus.;—Dr. F. Tangl comes
to the conclusion that the sharp boundary between the nucleus and the
cell-body disappears when the achromatic nuclear membrane is de-

* Arch. Ital. Biol., xi. (1889) pp. 118-33.
+ Math. u. Naturwiss. Bericht. aus Ungarn, vi. (1889) pp. 61-77 (1 pl.).

1889. 2M

494 SUMMARY OF CURRENT .RESEARCHES RELATING TO

stroyed, and that it does not reappear until a new membrane is formed
around the daughter-figures. During mitosis there is a much closer
connection between cell-body and nucleus than when the nuclei are at
rest; this is probably due to the intermixture of the nuclear material
with the interfilar mass. Particular attention is directed to the influence
of preservative reagents on the characters of the cell.

Nerve-cells in Birds.*—Sig. E. Falzacappa has investigated the
origin of the nerve-cells and the minute structure of the central nervous
system in birds. His observations led him to the following conclu-
sions:—(1) there is in the embryonic state an entire absence of the
polygonal nerve-cells, but the primordial cells are identical with those
of the neuroglia of the adult; (2) cells arise from the primitive elements
by gemmation, after the fashion of a Nostoc chain; (3) these new cells
are gradually transformed into the free polygonal elements; (4) the
nuclei of the primordial cells resemble those of the adult neuroglia ;
(5) the primitive cells furthermore respond to reagents in the same way
as the neuroglia or the perfect polygonal cells. ‘The primordial cells of
the embryonic brain are therefore neurogenetic, giving rise to the
special nerve-cells. The author proceeds to bring forward detailed
histological evidence in support of the conclusion that the specific
nerve-cells have the same nature as those of the neuroglia. Plates are
promised in a completed memoir,

Form and Size of Red Blood-corpuscles of Adult and Larval
Lampreys.{—Mr. 8. H. Gage has examined the red blood-corpuscles of
the lampreys of Cayuga Lake. The varying statements made with
regard to these cells give an interest to his observations. Wagner, in
1838, described the circular outline of these cells, and he, with Kéllker
and others, have noted their biconcave character. Gulliver and Gunther
state that they are flat or biconvex, and neither Gegenbaur nor Wieders-
heim draw attention to their peculiarities; Shipley and Thompson have
asserted that the blood-corpuscles of the larvee were oval and of the
adult circular. Mr. Gage finds that the red blood-corpuscles of both
adult and larval lampreys are circular, biconcave, nucleated discs; the
observation that they run into rouleaux, like those of all Mammals,
except the Camelide, appears to be new.

y. General.

Fresh-water Fauna of East Africa.{—Dr. F. Stuhlmann has a pre-
liminary report on his investigation of the fresh-water fauna of East
Africa. The Ostracoda are well represented, both by species and indi-
viduals, and there appear to be some very remarkable forms among them.
The Oligochzeta—Perionyx, Eudrilus, and Digaster—are very numerous;
there are several species of Nais, and a large number of Dero; a new
species of Aolosoma was found in enormous quantities. Turbellarians
appear to be scarce. Of Nematodes some small forms of Rhabditis are
reported. Conochilus volvox is very common. A small clear greyish-
green Hydra with five arms was observed. The Protozoa are very
numerous, there being quite a series of Rhizopods, several species of
Vorticella, &c., and a number of Flagellata.

* Bull. Soc. Nat. Napoli, ii. (1888) pp. 185-93.
+ Proc. Amer. Soc. Micr., x. (1888) pp. 77-83.
¢ SB. K. Akad. Wiss. Berlin, 1888, pp. 1255-69.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 495

B. INVERTEBRATA,

Lymphatic Glands of Cephalopods and Decapodous Crustacea.*—
M. L. Cuénot considers that the organ in Cephalopods which Férussac
and d’Orbigny regarded as the pellicular appendage of the auricle, and
Owen as the homologue of the second branchial heart of Nautilus, is a
- lymphatic gland. He describes it as being bounded externally by a
thick epithelial layer; its cavity is traversed by a complicated network
of connective tissue, in the meshes of which there are a number of
nuclei and of cells which exhibit the peculiar mode of development of
lymphatic cells; that is to say, whose nuclei become gradually surrounded
by refractive granules, which form the characteristic and constant con-
tents of amcebocytes. In the decapodous Crustacea there are two sets of
lymphatic glands; the first and most important (and, above all, the most
constant) is situated in the gill between the efferent and afferent vessel ;
the other may be seen in a Crab by carefully raising the dorsal carapace
and removing the cuticular matrix ; to the latter it adheres strongly. It
begins a little below the heart on either side of the middle line and
terminates at the level of the last pair of thoracic appendages; each of
these glands has the form of an elongated pouch, which is slightly con-
tractile and communicates freely with subjacent venous lacune. In
section it is seen to be bounded externally by the chitinogenous matrix ;
there then comes a zone of irregularly disposed muscular fibres, and
then a network of connective fibres, in the cavities of which there are a
number of nuclei and cells. The contents of a living gland were found
to consist of a considerable number of mature amcebocytes, filled with
refractive granules and developing nuclei, mixed with numerous reserve-
‘products. In the Brachyura these organs appear to be easily seen;
among the Macroura they have been found active in Pagurus striatus
and Hupagurus Prideauxi, but greatly reduced in Galathea strigosa and
the Spiny Lobster.

Mollusca.
a. Cephalopoda-

Structure of Siphon and Funnel of Nautilus Pompilius.t—Mr. H.
Brooks has some preliminary remarks on this subject. ‘The siphon com-
mences in the first chamber as a cecum, the closed end resting against
the inner surface of the apex of the shell; it consists of a series of
tubular sections extending from septum to septum, and increasing in
-diameter as the chambers expand. Each section is made up of an
outer calcareous sheath, and an inner tube of conchiolin. In the outer
sheath there are spicules which overlie one another, and are arranged in
such a way as to form an exceedingly porous structure; the spicules are
fusiform, and are, as a rule, arranged in stellate figures; those that ex-
tend beyond the outer surface of the sheaths often end in irregular
knobs, many of which have the appearance of chestnut burrs. In very
young siphons, the sheaths are made up of slender threads, placed in the
same way as the spicules of the older sheaths, The spicules are made
up of slender transparent sticks of calcareous matter, which are held
together in bundles by organic matter. There seems to be a well-marked
period in the growth of the siphons when they first commence to form
spicules, but this, as yet, has not been exactly determined.

* Comptes Rendus, eviii. (1889) pp. 863-5.
+ Proc. Boston Soc, Nat. Hist., xxiii. (1888) pp. 380-2 (2 pls.).
2m 2

496 SUMMARY OF CURRENT RESEARCHES RELATING TO

The conchiolin tube commences as a closed sac fitting into the
sheath of the apical chamber ; it extends unchanged in thickness through
the first funnel; from the second to the fourth septum the tubes are
much attenuated. At about the fifth, the tubes no longer pass through
the funnels, but become disconnected. The older funnels are made up
of five layers:—(1) an outer layer formed by the anterior end of a
posterior sheath, where it embraces the funnel ; (2) a darker and denser
layer than the outer layer which contains more organic matter; (&) the
shell layer of the funnel proper; (4) the dense layer forming the
anterior end of an anterior spicular sheath ; and (5) an inner layer that
is extremely short, and reduces the opening of the funnel at its posterior
end. The last two layers are not present in the funnel of the living
chamber.

So-called Organ of Verrill in Cephalopoda.*—Dr. J. Brock points
out that the so-called organ of Verrill in Cephalopods was discovered
and described by Heinrich Miller more than thirty years ago, while
Bebretzky has made some observations on its development. The recent
statement of Mr. Laurie that the organ is absent from the adult Loligo
and Ommastrephes is probably due to the fact that preserved material
only was examined; Miiller himself was aware that the funnel-organ
was completely destroyed by the ordinary preservative fluids. The
organ, indeed, has been seen in so many Cephalopods that it may well
be said to be found in the class as such. The author confirms the
account given by Miiller as against the discrepant description of
Laurie.

B. Pteropoda.

Morphology of Spinous Sacs of Gymnosomatous Pteropoda.t—Dr.
P. Pelseneer objects to the view recently enunciated by P. Schalfejeff
as to the homology of the “sacs 4 crochets” with any part of the arms
of Cephalopoda. These arms and the organs which they carry are
entirely pedal in nature, while the sacs of all the Gymnosomata are
inserted on the internal wall of the buccal cavity. As the Aplysina
have the greatest affinities to the Gymnosomata they should be examined
when it is sought to explain the nature of the sacs; now, in Notarchus
the buccal cavity is lined by spinous hooks, and those found in the
Pteropods are only specializations of the spinous palatine vault of
Notarchus. It is to be noted that the sacs are not always as long as in
Clione or Pnewmodermon ; in Dexiobranchza, which is the most primitive
of existing Gymnosomata, and in Clionopsis they only form slight
depressions in which the hooks are implanted.

y. Gastropoda.

Ventral Nervous Mass of Fissurella.s—Dr. L. Boutan deals with
some criticisms of Dr. B. Haller. That author has asserted that the
ventral nervous mass forms a homogeneous centre in which two distinct
portions cannot be made out ; and that the centre is single. Dr. Boutan
declares that this is not the case, for two centres may be fused histolo-
gically, and yet be distinct morphologically, and this is the case with
Fissurella and a number of other Molluscs.

* Nachrich. K. Gesell. Gottingen, 1888, pp. 476-8.
+ See this Journal, 1888, p. 932. t Zool. Anzeig., xii. (1889) pp. 312-4.
§ Arch. Zool, Exper, et Gén., vi. (1888) pp. 375-421 (8 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 497

The study of a series of sections shows that the histological separation
of the centres is not more marked in the upper part of the nervous mass,
where authors seem to agree in recognizing the presence of pedal ganglia
and the first two asymmetrical ganglia, than in the lower part of the
neryous mass. The study of larve shows that the ventral mass is
certainly formed of two distinct nerve-centres (first two asymmetrical
ganglia and pedal ganglia). If it is impossible to establish a histological
distinction between the two centres, on account of the continuity of the
layer of peripheral nerve-cells, it is quite easy to distinguish in the
nervous mass, by the aid of the groove and of the two orders of nerves,
what part belongs to either of the fused centres. An examination of
sections shows that the general form of the four ganglia which serve to
form the nervous mass as a whole, is that of four cylinders united by
pairs, and closely applied to one another by one of their faces. The
structure of the epipodium and the close relations which it has with the
mantle in the young Fissurella should lead us to regard it as part of the
mantle, and to keep for it the name of inferior mantle.

Descent of Ova in Helix.*—M. J. Pérez has investigated the descent
of the ova in the canal of the hermaphrodite gland of Helix. At what-
ever season the efferent canal is examined, the inferior part of the tube
is always found filled with sperm. It is evident that the ova must pass
through the efferent canal a short time before they are found in the
diverticulum. The author has dissected a large number of specimens
day by day. He found in some that the canal was less distended by
sperm than usual, and had a peculiar greyish appearance. Microscopic
examination of the contents showed that the sperm was more or less
completely altered, and that the epithelium of the efferent canal was also
being destroyed. When the sperm and epithelium are both completely
absorbed, the efferent canal is empty and the way is open for the ova.
The author has not yct been able to observe their passage directly, and
thinks it is effected in a very short time.

Anatomy of Clione limacina.t—Herr P. Schalfejeff commences by
directing attention to the so-called jaws of this mollusc. The walls of
the sheath are formed of a thick layer of circular muscles covered by a
very thin investment of connective tissue. When at rest the jaws have,
externally, a layer of longitudinal muscles, part of which forms the
retractor of the seizing apparatus ; the spaces between the muscles contain
connective substance which forms a thick layer of fibrous appearance, a
cylindrical epithelium, and an armature of hooks which is connected
with the epithelium. The hooks consist of a horny substance which is
not chitin, and rests on giant-cells, the finely granular protoplasm of
which fills up the hollow of the tooth, as far as its tip. Similar
characters have been observed in Pnewmodermon.

As to the connection between the organ of Bojanus and the pericardial
cavity, the author affirms that there is not merely an opening, but a
typical funnel; the epithelium of this, which is characterized by very
long flagella, passes on the one side into the very flat epithelium which
covers the inner surface of the pericardial cavity, and on the other into
the glandular epithelium of the kidney.

* Comptes Rendus, eviii. (1889) pp. 365-7.
+ Zool. Anzeig., xii. (1889) pp. 188-90.

A498 SUMMARY OF CURRENT RESEARCHES RELATING TO

Reproductive Organs of Valvata piscinalis.*— Dr. P. Garnault
gives a description of the reproductive organs of Valvata piscinalis ; at
first sight they appear to differ a good deal from those of other andro-
gynous Molluscs, but the resemblances are seen when the relations of
the parts are laid down as in a ground-plan. At the same time they are
distinguished by the fact that there is a communication between the
efferent canal and the copulatory pouch, and this ensures self-fecundation
in cases in which copulation is not effected. Further details and
illustrative figures are promised.

5. Lamellibranchiata.

Morphology of Teredo.t—M. A. Ménégaux has investigated the
homologies of the different organs of this aberrant Lamellibranch.
Having discovered the anterior adductor-muscle, he is able to say that
it is a dimyarian; this muscle is very small, is covered by a pallial
lobule and separated from the posterior adductor by the rectum and a
vessel which accompanies it. The “ palettes” are moved by three special
muscles, the largest of which arises from the siphonal muscles, the other
two are lost in the mantle. The single aorta corresponds anteriorly
with the anterior and posterior aorte of other Lamellibranchs, but after it
has passed the posterior adductor it no longer corresponds to the posterior
aorta. To the right of the rectum it gives off two lateral pallial vessels ;
then it passes slightly to the right, follows the right siphonal nerve and
gives off a branch to each of the siphons. This asymmetry of the circu-
latory system is more apparent than real; it reminds one of what obtains
in Pholas, and the difference is due to the fact that the mantle of Teredo
being greatly developed in a longitudinal direction the posterior aorta
is of considorable length before it bifurcates to go to the siphons.

Origin of Unionide.{—Prof. M. Neumayr has no doubt that the
great stock of the Mollusca was originally developed in the sea. Of
the fresh-water groups now existing, the most widely distributed and
important of the Lamellibranchs are the Unionide, which appear to be
descended from the marine Trigonia. 'This form has the hinge of the
peculiar schizodont type, and, though the hinge-structure is exceedingly
variable in the Unionide, we find on close examination of normal forms
that they may be referred to the same type. Affinity is also shown by
the structure of the gills, the separation of the two lobes of the mantle,
and the absence of siphons. In both groups the nacreous shell exhibits
extraordinary development, there is a strong epidermis and a resemblance
in the arrangement of the muscular scars. It is particularly remarkable
that in many geologically young Uniones of Pliocene and recent times
shell-ornaments appear as retrogressive structures, such as occur else-
where only in the Trigoniz.

Molluscoida.
a, Tunicata.

Developmental History of Distaplia magnilarva.§—In the first of
his memoirs on the development of this compound Ascidian, Dr. M. v.
Davidoff deals with the maturation of the egg. The structure which is

* Zool. Anzcig., xii. (1889) pp. 266-9.

+ Comptes Rendus, eviii. (1889) pp. 537-8.

t Anzeig. K. Akad. Wiss. Wien, 1889, p. 4; Ann. and Mag. Nat. Hist., iii.
(1889) p. 372. § Mittheil. Zool. Stat. Neapel, ix. (1889) pp. 113-78 (2 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 499

generally known as the egg in Ascidians is not what is ordinarily
regarded as such; it is rather an ooblast which produces eggs, and it is
consequently comparable to the ooblast of the Appendicularia (Fritillaria).
The eggs produced by the ooblast function as such in the Appendicularia,
while in Ascidians only one is capable of fertilization; all the rest
become aborted and may be spoken of as testa-cells. The nuclei of all
the eggs arise as buds of the nucleus of the ooblast or karyoblast. In
Ascidians they are formed as simple constrictions of parts of the
membrane and reticulum of the karyoblast, without the intervention of
the nucleolus. On the surface of the ooblast of Distaplia they increase
karyokinetically. Later on the muscular buds or nucleogemme become
surrounded by part of the protoplasm of the ooblast; and thus become
cells, and separate from the ooblast. The eggs of the Appendicularia
retain, on constriction, a follicular investment, with which the complex
of ooblasts of these animals is from the first surrounded. In Ascidians
the abortive eggs do not retain any covering, but lie in the space between
the egg and the follicular epithelium.

There is reason to suppose that the reduction of the eggs formed by
the ooblast goes still further than is the case in Ascidians. The nucleo-
gemme lose their specific protoplasmic covering and become lost in the
ooblast. The various phenomena of formation of buds of the karyoblast
which have been several times observed in Vertebrates are probably of
the same character. In later stages of cleavage it may be seen that some
of the abortive eggs of Distaplia are entirely the large endublast cells,
while others remain for some time without taking any part in forming
the tissues of the larva. When the abortive eggs have left the ooblast
the latter forms a true egg. All the protoplasm of the egg breaks up
into yolk-bodies in such a way that no intermediate substance is retained.
At the same time the membrane and reticulum of the germinal vesicle
become lost in its karyoplasm and are converted into a plasmatic,
actively moving, amceboid body, which gradually extends itself in a
plexiform fashion in the whole egg (ergoplasm). The nucleolus,
which has till now remained passive, is converted by internal histo-
logical differentiation into a “polar nucleus” with membrane, nuclear
network, and nucleolus. By the action of the ergoplasm the polar
nucleus is conveyed to the periphery of the egg; it loses its membrane
and network, its chromatin becoming converted into chromatic loops,
which give rise to a chromatic figure when the polar globule is con-
- stricted off. It behaves therefore just as the germinal vesicle is known
to do. The formation of one polar globule was observed, and this must
be regarded as cell-division. JBiitschli’s hypothesis that the polar
globules are rudimentary eggs is so far supported by what obtains in
Distaplia where the abortive eggs are all of the same size after their
division. The cleavage nucleus is surrounded by a large quantity of
ergoplasm ; when observed it was found to consist of a large number of
similar merites. The ergoplasm is to be identified with the protoplasm
of Kuppfer.

8. Bryozoa.

Anatomy of an Arenaceous Polyzoon.*—Mr. A. Dendy describes a
remarkable new genus of ctenostomatous Polyzoa, found near Port Phillip
Head, which he calls Cryptozoon, and of which two species, C. wilsoni and

* Royal Soe. of Victoria, 1889, 8vo, 11 pp. and 3 pls,

500 SUMMARY OF CURRENT RESEARCHES RELATING TO

C. concretum, have been distinguished. The organism forms tubular,
chitinous zocecia enveloped in common aggregations of sand; the poly-
pides are provided with a muscular gizzard containing two horny teeth.
The chief difficulties in the way of the study of the soft tissues consist
in the very minute size of the individual polypides, and in the difficulty
experienced in separating them from the mass of sand-grains in which
they are enveloped and to which the zocecia firmly adhere.

The ccencecium is dichotomously branched and the branches come off
in several planes; it consists primarily of a slender chitinous tube; the
whole is divisible into what may be termed nodes and internodes; the
former are dense aggregations of grains of sand firmly held together by
the chitinous zocecia, while the latter are longer or shorter, slender,
chitinous tubes connecting the nodes together. It is to be especially
noted that the tubular internodes are not continuous through the
substance of the sandy nodes, but each, on entering the sandy mass,
breaks up into a kind of rete mirabile, formed chiefly of the delicate
tubular Zocecia. The zocecia are very delicate, and it is possible that,
in Cryptozoon, as in those horny sponges which take on an arenaceous
habit, the chitinous portion of the skeleton is actually reduced in con-
sequence of the addition of the sand, which may be considered as
supplementing, and, possibly, to a certain extent replacing the chitin.
The wall of each internode appears in optical longitudinal section to be
clothed internally with a deeply staining epithelium, the cells of which
secrete the chitinous wall of the tube; this lining is, no doubt, a direct
continuation of the ccelomic epithelium of the polypides, and appears to
be the only organic connection between the different members of the
colony.

So much of the anatomy of the polypide as could be made out is
described. The epithelium of the tentacles does not present the same
character over the whole surface; on the inturned face of each tentacle
there are two parallel longitudinal rows of small, columnar cells, each
of which contains a relatively large, deeply staining nucleus. The cilia
on the tentacle are nearly as long as the tentacle is thick, and they
always move in a perfectly definite and regular manner. The alimentary
canal is very complex, and five distinct parts—pharynx, cesophagus,
gizzard, stomach, and intestine—can be recognized in it.

The gizzard is globular in shape, and has thick muscular walls, con-
sisting mainly of a stout circular band of muscles oval in section, and
composed of a great number of delicate fibres, surrounding two relatively
large chitinous teeth. These last are squarish in shape, and flattened.
The stomach is very large, elongated and saccular, and is differentiated by
the character of its lining membrane into two totally distinct regions—-
an upper, non-digestive, and a lower, digestive portion. The entire ali-
mentary canal is clothed externally by a delicate, closely-fitting, flattened
epithelium, the nuclei of which are plainly discernible over the greater
part of its surface. The muscular system is well developed.

The author remarks that it is interesting to find a Polyzoon acquiring
a habit with which we are already familiar in other groups, such as
Foraminifera, Sponges, and Annelids. The genus is obviously closely
allied to Bowerbankia, from which it differs most markedly in the habit
of agglomerating particles of sand on to the zoccia. In conclusion, the
distinctive characters of the new species are briefly enumerated.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 501

Structure and Metamorphosis of Larva of Flustrella hispida.*—
M. H. Prouho has made a study of the larva of this Bryozoon. In the
oral region there is a pyriform organ with a vibratile plume and a
sucker, and in the aboral region an ectodermic pad ; the two regions are
separated by a ciliated corona. In addition to these there is an internal
hollow organ, the cavity of which communicates with the exterior by an
orifice on the oral surface between the pyriform body and the sucker ; it
may be regarded as an embryonic digestive sac. As the larva approaches
the free stage the walls of the sac become less and less distinct, and are
finally absorbed. In this point the free larva differs essentially from
Cyphonautes, in which, as all agree, there is a digestive tube. The
ectoderm and mesoderm become considerably differentiated in the free
larva. A bundle of nerve-fibres, with which are connected some unipolar
cells, directly connects the pyriform organ with the aboral pad. Some
of these fibres extend as far as the vibratile plume and make their way
between the glandular cells of the pyriform body, while a right and a
left bundle become detached to furnish fibres to the ciliated cells of the
groove, to those of the corona, and to the very numerous vibratile swel-
lings which are scattered over the dorsal surface. Asall the ciliated cells
of the larva are connected with the aboral ectodermic pad, and as this is
provided with rigid cilia, it appears to be justifiable to regard it as
having a sensory function.

On each side of the larva there are parietal muscles comparable to
those of the adult, and longitudinal muscles, which are adductors of the
valves, traverse the middle of the larva. The most interesting meso-
dermal structure, and one which has not yet been noticed in the larve of
marine ectoproctous Bryozoa, is a subepidermic cellular layer which is
particularly developed in the aboral region.

When the larva becomes fixed the corona is folded inwards, and the
sucking plate fuses with the skin all round the free edge of the valves;
the changes which now occur agree with what are seen during the
fixation of a cheilostomatous larva. The corona, pyriform body, nervous
system, and a portion of the musculature then undergo degeneration,
and form a mass of globules enveloped by the mesodermic layer. The
thickened plate of the ectoderm soon afterwards proliferates rapidly,
and forms an invagination below the cuticle, which does not itself take
part in it.

Arthropoda.

Segmental Sense-Organs of Arthropods.t—Mr. W. Patten states
that the cephalic lobes of Acilius are composed of three segments, each
of which contains a segment of the brain, optic ganglion, and optic plate.
It is very probable that these characters are common to all Insects.
The segmental nature of the eyes is more clearly seen in the embryos of
scorpions, spiders, and Limulus, where it can be shown that they are
serially homologous with one or more pairs of sense-organs on each
segment of the thorax. If the cephalic lobes of scorpions could be
stretched out the eyes would lie, as in Acilius, on the thickened
outer edge of each segment. This thickened edge is represented in the
post-oral region of the pleure of the thoracic segments, each of which
bears two large sense-organs close together near the outer edge of the

* Comptes Rendus, eviii. (1889} pp. 1023-5.
t Journal of Morphology, ii. (1889) pp. €00-2.

502 SUMMARY OF CURRENT RESEARCHES RELATING TO

base of the legs. Mr. Patten thinks it is clear that the eyes are serially
homologous with these thoracic sense-organs. The latter contain a
cavity, shaped like the bowl and stalk of a goblet, lined with striated
cuticle similar to that found at an early stage over the eyes of Acilius.
The ventral cord and brain of Arthropods are at first composed entirely of
minute sense-organs, which in scorpions have the same structure as the
segmental ones at the base of the legs. Further details are promised.

a. Insecta.

Formation and Fate of Polar Globules in Eggs of Insects.*—
Dr. H. Henking has examined the early stages of development in the
eggs of various Insects.

In the egg of Pyrrhocoris apterus the first polar globule appears three
or four hours after deposition; it lies ina shallow depression of the
marginal zone of protoplasm ; below it may be seen the second globule
in a more or less advanced stage. When the first embryonic cells begin
to be formed within the egg, the globules come to be placed freely in a
cavity which is altogether surrounded by the marginal protoplasm; they
have not yet, however, acquired their definite position, In eggs about
twenty hours old the globules lie outside the protoplasm on the surface
of the ventral yolk-material. The author’s opportunities of observation
have not as yet enabled him to definitely settle the fate of these bodies,
~ but he is satisfied that the globules are again taken up by the egg. In
the case of various Lepidoptera, Diptera, and Hymenoptera, Dr. Henking
has not been able to observe the expulsion of the polar globules. In
Tenebrio molitor one is certainly expelled, and the same is the case in
Lampyris splendidula.

Vision of Insects.t—Dr. F. Dahl, who believes that Insects can dis-
tinguish form, traverses certain conclusions of Prof. Plateau, for which
he does not believe there are physiological grounds. He relates an
account of an experiment which he made with a bee (Hylzus morio),
whose enemy is the spider Attus arcuatus ; thinking that the olfactory
sense might give the insect warning, he killed a spider, and smeared a
paper-sphere with its blood, but of this the bee was not at all afraid.
The male of the dipterous Dolichopus plumipes has a beautiful and
regular pinnation of the first tarsal joint of the middle leg; this
apparatus cannot be of use during copulation. When the insects were
pairing it was observed that the male hovered over the female in such a
way as to bring its middle tarsi close to the eyes of the female.

Dr. D. Sharp ¢ devoted a large part of his Presidential Address to
the Entomological Society of London to the subject of the vision of
Insects. He thinks we may fairly conclude that it is quite uncertain
what insects do see, or whether they see at all, if we use the word seeing
in association with our own plane-picture seeing. He lays stress on
the point that, certain central structures in connection with the verte-
brate sense of sight not being present in insects, other structures to
compensate for their absence may be expected to occur in more direct
connection with the eye. If so, it becomes highly probable that the
functions of the insect-eyes are not only dissimilar from ours, but are

* Nachr. K. Gesell. Gottingen, 1888 (1889) pp. 444-9.
+ Zool. Anzeig., xii. (1889) pp. 243-7.
t Trans. Entomol. Soc. Lond., 1888 (1889) pp. xlviii—Lxix.

ZOOLOGY AND BOTANY, MIOROSCOPY, ETC. 503

also more complex. He thinks that, from the anatomical side, we as
yet know very little about how or what an insect sees, and he thinks it
highly probable that its sight is very different from our own, and that
continuous picture-vision forms no part of it; he thinks it possible that
the compound-eye may have two or three distinct kinds of perception.
At the same time he is of opinion that the ocular powers of insects are
very perfect in their way, although that way may be very different from
ours.

Hermaphroditism in Gastropacha.*—Prof. P. Bertkau describes a
case of external hermaphroditism in Gastropacha quercus, where the
right antenne and wings were those of a female, those on the opposite
side characteristically male. In other ways the external . secondary
characters were mingled, but the thorax and posterior body were wholly
female. The state of the internal organs was at the same time investi-
gated, obviously a point of much importance. The gonads were wholly
degenerate, but there were almost normal female ducts and auxiliary
structures. There was no hint of internal male organs. Bertkau
believes that an individual has rudiments of both kinds of secondary
sexual characters, that predominance of one sex in the organism
suppresses the secondary features of the other, while complete atrophy
of the essential organs is naturally enough associated with an external
average. The author notes the occurrence of 315 cases of “ hermaphro-
ditism ” among Arthropods :—8 Crustaceans, 2 Arachnids, 305 Insects.
Of the latter, 244 Lepidoptera, 48 Hymenoptera, 9 Coleoptera,
2 Orthoptera, and 2 Diptera are known. Among Arachnids, a specimen
of Dizea dorsata was male as regards cephalothorax, limbs, and palps, but
female in the hinder part of its body.

Myrmecophilous Insects.j — Herr E. Wasmann continues his
interesting investigations on the life of myrmecophilous beetles and their
relations to the ants. He distinguishes (1) true guests which are cared
for and fed by the ants (Atemeles, Lomechusa, Claviger); (2) forms
which are tolerated but are not treated with special friendliness, and
which feed on dead ants or rotting vegetable material (Dinarda, Heterius,
Formicoxenus, &c.); (8) ant-eating species, pursued as enemies, or only
tolerated as a matter of necessity (Myrmedonia, Quedius brevis, &c.), to
which may be added parasites like Phora. The three sets are not
rigidly separable.

Atemeles and Lomechusa have taken on some of the habits of their
hosts, aud are more adapted than other myrmecophilous insects. The
best known species of Atemeles (A. paradoxus and A. marginatus) are
found most frequently in the nests of Myrmica, more rarely in those of
Formica and others. On the contrary, A. pubicollis seems to be more
frequent in Formica nests. The species of Atemeles are lively animals,
constantly moving their feelers, and experimenting with everything. If
one be attacked by a hostile ant, it first seeks to pacify its antagonist by
antennary caresses, but if this is unavailing it emits a strong odour
which appears to narcotize the ant. Wasmann describes how the ants
feed the Alemeles and are caressed and licked for their care, how one

* Verh. Nat. Ver. Preuss. Rheinld. (SB. Niederrhein. Gesell.), xlv. (1888)
pp. 67-8.

+ Biol. Centralbl., ix. (1889) pp. 23-8; Deutsche Entom. Zeitschr., 1886,
pp. 49-66, 1887, pp. 108-22; Tijdschr. vy. Entom., xxxi. (1888) p, 84.

504 SUMMARY OF CURRENT RESEARCHES RELATING TO

Atemeles feeds another, or even as a rarity one of the hosts. Yet the
beetles feed independently on sweet things, dead insects, and even the
unprotected young of the ants. The guests are licked and cleaned by
the hosts, as well as vice verséd; but the beetles are in reality quite
dependent upon the ants.

As to Lomechusa, it is represented in Central Europe by a single
species, LD. strumosa, which is almost always found with Formica
sanguinea, though occasionally with other forms. This beetle is much
larger, plumper, and more helpless than Atemeles ; its odour is different
and very like formic acid ; its relations to the hosts are more passive,
yet it can feed independently, for instance, on the larve and pupz of the
anits.

The other guests are rather pests than pets. They almost all live on
animal food, are often protected simply by prestige or by their odour.
The minute Oligota, Homalota talpa, Myrmecoxenus, Monotoma, Hysteride,
the small guest-ant Formicoxenus in the nests of Formica rufa, &c.,
appear to escape unnoticed.

On a change of abode, the myrmecophilous insects follow their
euests, or, as in the case of Lomechusa and Atemeles, they are taken with
them by force. While the ants themselves are well known to be very
exclusive, the guests can be shifted from nest to nest or even from
species to species. As Wasmann says, the guests seem to have
‘international relations.”

In commenting upon the above facts, Prof. Emery regards it as |
certain that the semi-domesticated, and in one sense parasitic forms like
Atemeles and Lomechusa, ave descended from thievish forms. They
retain some of the original traits, just as dogs and cats do in their
recently acquired tamed state.

Butterflies’ Enemies.*—Mr. 8. B. J. Skertchly, who has had oppor-
tunities of studying the question in virgin forest, discusses the habits
of the enemies of Butterflies. He comes to the conclusions that
mimicry is a protection from foes which attack butterflies on the
wing ; protective resemblance is a protection from foes which hunt
sleeping prey; mimicry was a protection from birds, but birds seldom
attack butterflies now, though butterfly-catching birds were formerly
more plentiful. The comparative rarity of mimicry shows the danger
to have been of relatively short duration. The shyness of butterflies
is a further proof of danger; it is now probably an inherited instinct.
Protective resemblance is almost universal, and .is a protection
during the sleeping hours. Ants seldom capture living butterflies.
The symmetrical mutilations of butterflies point to lizards and perhaps
small insectivorous mammals as the foes which hunt for sleeping butter-
flies. It is concluded that the amount of danger feared is measurable
by the efforts made to avoid it.

Alimentary Canal of Larval Lamellicorns.t—Sig. P. Mingazzini
communicates some new facts in regard to the structure of the alimentary
canal in the larve of some phytophagous Lamellicorns, belonging to the
genera Oryctes, Anomala, Cetonia, and T'ropinota. He notes the presence
of unstriped muscles in the mesenteron, for at least a period of the larval
life, and describes a new type of connective tissue and cry stalloids in the

* Ann. and Mag. Nat. Hist., ili. (1889) pp. 477-85,
+ Boll. Soc. Nat. Napoli, ii. (1888) pp. 130-4.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 505

nuclei of some cells in the midgut of Oryctes. The median ventral
groove of the midgut in the larve of Oryctes, Cetonia, and Tropinota is
a sort of glandular cecum with a digestive secretion, The sac which
forms the median portion of the proctodeum is the absorptive part of the
intestine in these larve.

Bees and Flowers.*—Dr. M. Kronfeld corroborates the old observa-
tion, which even Aristotle recorded, that bees do not fly at random from
one flower to another, but for a longer or shorter period restrict their
visits to one species. Three times before a bed of Cucumis the observer
detained a bee, and watched it return when liberated to the same kind
of flower though others were there in abundance. At a bed including
eight different kinds of flowers the bees were apparently blind to all but
one species. In a meadow with abundance of inviting flowers, repre-
senting nearly a score of species, Herr Kronfeld saw a humble-bee
visit within ten minutes twenty-eight heads of goat’s-beard, and no
others. The observations, therefore, show a considerable degree of
constancy in the bees’ visits.

Stigmata of Hymenoptera.j—M. G. Carlet finds that the stigmata
of the Hymenoptera are always open, and that there is not the least trace,
at their orifice, of any obturator apparatus. They are of extremely
small size, and have, consequently, received but little attention; more-
over they are generally covered externally by hairs which are often
ramose, and which serve to prevent the introduction of foreign bodies,
even in the form of fine dust. The tracheal trunks may be opened or
closed at the will of the insect; this mode of closure, which the author
calls opercular, is effected by means of a special tracheal muscle which is
inserted in the trachea, above a cleft which is found on it in front of
the stigma; the tracheal muscle raises the upper lip of this cleft,
that is to say the operculum, in the mode of the lid of a snuff-box.
The difficulty of the investigation to which M. Carlet has lately devoted
himself may be estimated from the fact that this muscle is more delicate
than the finest silk-thread of commerce.

Development in Egg of Musca vomitoria.t—Dr. A. Voeltzkow
has published a full account of his researches on this subject. Tio our
notice of his preliminary communication § we may now add the follow-
ing. The Malpighian vessels are formed as evaginations of the hind-gut,
and the sucking stomach as an evagination of the fore-gut. The salivary
glands are formed by invagination of the ectoderm in the anterior part
of the head and are laid down separately; later on they open by a
common efferent duct into the mouth. The ventral cord, when fully
developed, consists of two longitudinal cords of nerve-fibres which are
inclosed by nerve-cells ; in correspondence with each segment the nerve-
cells are separated by a ventral mass of cells. The longitudinal trunks
lie close to one another, but do not fuse, being separated where they
touch by a fine layer of cells. In the course of its further development
the ventral cord shortens considerably ; the author does not agree with
Weissmann that the indications of the earlier segments are lost. He is

* Biol. Centralbl., ix. (1889) pp. 28-30.

t+ Comptes Rendus, eviii. (1889) pp. 862-3.

} Arbeit. Zool.- Zoot. Inst. Wiirzburg, ix. (1889) pp. 1-48 (4 pls.).
§ See this Journal, 1888, p. 572.

506 SUMMARY OF CURRENT RESEARCHES RELATING TO

inclined to accept Hatschek’s statement that the brain arises from the
lateral parts of ectoderm laid down separately.

A Spinning Dipteron.*—Prof. J. Mik describes a remarkable veil
which the male of Hilara sartor Beck. carries about with him in his flight.
This veil is a thick filamentous tissue, without any “sort of seam in its
longitudinal axis,” or “S-shaped threads,” as Becken describes. It is not
borne on the back of the abdomen of the male, but is held on the under
surface of the body by the feet.

Biology of Gall-producing Species of Chermes. ,—Dr. F. Low has
a contribution to the interesting subject of the biology of gall-producing
species of Chermes which is now attracting so much attention. His
experiments enable him to confirm two of the statements of Blochmann
and Dreyfus—the wandering of the winged individuals of the first or
gall-ceneration of Chermes abietis from the pine to another species of
Conifer, and the division of this generation into two unequal parts, each
of which forms the commencement of a special series of developmental
changes. He also makes a contribution to the literary side of the
question.

Dr. L. Dreyfus ¢ has again § a communication on the subject; he finds
that Ch. hamadryas must cease to be regarded as an independent species,
and the animals which have been so called must be considered to belong
to the developmental series of Ch. strobilobius ; there are, therefore, no
species which can now be said to be confined to the larch.

Egg of Melolontha vulgaris.||—Dr. A. Voeltzkow has made a study
of the development of the egg of Melolontha vulgaris, but unfortu-
nately he was not able to investigate the earliest stages. The germinal
layers are formed in the manner first described by Kowalevsky for Insects,
namely, by invagination in the middle line of the germ-stripe, the
groove thus formed being converted into a tube; this tube is flattened
out in a dorgo-ventral direction, becomes cut off from the blastoderm,
and differentiated into an outer and an inner layer. ‘The cells of either
layer fuse completely with one another, so that no sign is left of the
previous tube or cleft. The author is not in agreement with Heider, for
he is unable to accept the account of the differentiation of the lower
layer into two distinct cell-layers. A very important point in Heider’s
memoir is the account of the formation of the mid-gut; but Dr.
Voeltzkow’s own investigations, coupled with a critical notice of the work
of other observers, seem only to lead him to the conclusion that the
question of its origin is well worthy of renewed investigation, which he
proposes to take with Blatta as his subject.

Anatomy of Blattide.{—Dr. E. Hasse states that Mr. EH. A,
Minchin’s lately discovered ** organs in Periplaneta orientalis are, as
their discoverer supposed, stink-glands; it may be easily proved in the
larve. The hairs which take up the secretion of the glands and diffuse
it call to mind those described by Fritz Miller as associated with the
stink-clubs of the females of Maracuja. In both the secretion appears
to be of an oily character. Comparable also are the eversible dermal

* Verh. K. K. Zool.-Bot. Gesell., xxxviii. (1888) pp. 97-8.

+ Zool. Anzeig., xii. (1889) pp. 290-3.

t T. c., pp. 293-4. § See this Journal, ante, p. 380.
| Arbeit. Zool.-Zoot. Inst. Wiirzburg, iv. (1889) pp. 49-64 (1 pl.).

q Zool. Anzeig., xii, (1889) pp. 169-72. ** See ante, p. 204.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 507

appendages found by Gersticker in Corydia, and the structures of similar
function found in larve, and lately described by Klemensiewicz. Some
account is given of the peculiar organs found between the sixth and
seventh dorsal plates of Phyllodromia germanica.

8. Myriopoda.
Spinnerets of Myriopoda.*—M. J. Chalande found in Scolopendrella

immaculata an apparatus composed of two distinct glands, which open
outwards in the two appendages which are placed on the margin of the
anus. ‘They have the form of elongated tubes which end blindly about
the fifth anal segment. The anterior portion forms the gland proper
and the hinder part its excretory canal. The gland is occupied by a
single large cavity filled with the secreted substance ; its wall consists
of fine cells charged with fine granulations. The terminal appendages,
which are formed by a single lanceolate joint ending ina long and strong
spine, are traversed by a cavity at the end of which is an aperture. The
secreted liquid is remarkable for its great viscosity, and does not mix
either with water or glycerin; on coming. into contact with air it
hardens rapidly. The threads thus formed differ from those of Spiders
in being not elastic but fragile, like a thread of glass.

Myriopoda of Mergui Archipelago.t—Mr. R. I. Pocock hag an
account of the Myriopods collected by Dr. Anderson ; they are, appa-
rently, the first recorded from these islands, and they are, in many
cases, referable to species which have been described from the Oriental
region. Those that are new are, with one exception, small and incon-
spicuous individuals, which would in all probability have been overlooked
or ignored by any but a scientific collector. Of the Chilopoda only one
—a species of Himantarium—is new; of the Diplopoda, Glomeris has
one, Paradesmus two, Spirostreptus two, and Spirobolus one new species.
During the printing of his paper the author was enabled to examine
two large collections of Burmese Myriopods, and he has now found that
the Myriopod fauna of Mergui has certainly been derived from that of
South Burmah. He has therefore described the new Glomeris from
Mergui not as a new species, but as a variety of a new Glomeris—G.
carnifea—from Tenasserim, arguing that the continental form ig the
parent of that found in the island.

y. Prototracheata.

Maturation of Ovum in Cape and New Zealand Species of
Peripatus. {—Miss L. Sheldon has had the opportunity of studying the
maturation of the ovum in three species of Peripatus. In P. capensis
and P. Balfouri the ova arise by a growth of some of the nuclei of the
germinal epithelium ; apparently any of the nuclei may give rise to ova,
Each ovum has a large round central nucleus, and is surrounded by a
layer of protoplasm, which is not separated from that of the germinal
epithelium. As the ova increase in size they become surrounded by a
thin shell. As the nucleus passes to the periphery it is homogeneous,
and has only slight traces of a reticulum. After the disappearance of
the germinal spot the wall of the germinal vesicle becomes irregular in

* Comptes Rendus, eviii. (1889) pp. 106-8.
+ Journ. Linn. Soc. Loud., xxi. (1889) pp. 287-303 (not 330 as printed) (2 pls.).
t Quart. Journ. Micr, Sci., xxx. (1889) pp. 1-29 (3 pls.).

508 SUMMARY OF CURRENT RESEARCHES RELATING TO

outline and then disappears, its contents becoming fused with, and in-
distinguishable from, the cell-substance. As the ovary is full of
spermatozoa the ova are probably fertilized in it. They thence make
their way into the uterus. The youngest uterine ovum observed had no
nucleus ; a small spindle appears at one point at the periphery of the egg,
and a male pronucleus is present at the opposite side. The spindle
divides twice to form polar bodies, and the remainder of the spindle
remained as the female pronucieus ; it lies at a little distance from the
surface, and is lobed. The male pronucleus is large and rounded; the
two probably conjugate, though this has not been observed. The re-
sulting nucleus passes to the periphery; it is large and lobed, and soon
becomes surrounded by a large mass of dense protoplasm.

An account is also given of the maturation of the ovum in P. Nove-
Zealandiz, which differs not inconsiderably from that of the Cape
species; for example, spermatozoa are present in the receptacula seminis
and not in the ovary; the nucleus is at one period vacuolate, and no
polar bodies have as yet been observed.

In conclusion some general remarks are made on the origin of the
ova from germinal epithelium, the disappearance of the germinal vesicle,
the formation of the polar bodies, and the formation of the yolk. As to
the last question; while it has been suggested that the yolk arises in
the protoplasm of the egg itself, from the breaking up of the germinal
vesicle, or from the follicle cells, it is of interest to observe that
P. Nove-Zealandiz not only affords an example of all these three
methods, but also a fourth, for the yolk arises from yolk which is present
in the ovary itself. Miss Sheldon does not think she could have failed
to see polar bodies in P. Nove-Zealandiz had they been formed, and
she thinks that their absence in that species and their presence in the
Cape species can only be explained by supposing that they are in some
way dependent on the yolk, since in it lies the main difference between
the eggs. If this be so, it is clear the polar bodies cannot have the
significance which Weismann attributes to them, and in any case the
similarity between the two polar bodies in the Cape species is not what
we should have expected if their meaning were so different as Weismann
suggests.

6. Arachnida.

Life-histories of Glyciphagus domesticus and G. spinipes.*—Mr.
A. D. Michael finds that there is a hypopial stage in the life-history of
Glyciphagi, just as there is in that of Tyroglyphus, but it is far less
developed, and is not, so far as is known, an active stage. At present
we do not know whether it occurs in all species, but we do know that it
does not occur in the life of every individual of a species. The stage
is not the result of desiccation and other unfavourable circumstances,
but occurs as often under favourable conditions. In the species inves-
tigated it occupies the period between the penultimate ecdysis and that
immediately previous.

In G. spinipes the Hypopus is fully armed, and capable of moving its
legs, but not of walking or other active movement; as a rule, it does
not leave the skin of the young nymph within which it is formed; the
more adult nymph is formed within the Hypopus while the latter is still
within the young nymphal skin. In G. domesticus the hypopial stage is

* Journ. Linn. Soc. Lond., xx. (1889) pp. 285-98 (1 pl.).

ZOOLOGY AND BOTANY, MIOROSCOPY, ETO. 509

even more rudimentary, its representative retaining only the general
form of the creature, and having no legs or other external organs.

Encystation of Glyciphagus.*—M. P. Mégnin describes the process
of encystation in Glyciphagus cursor and spinipes. When extinction
appears inevitable the following remarkable life-saving modification was
observed. The organs liquefy, their substance forms a gelatinous
spherical mass within the body, and this mass becomes enveloped in a
cyst. This remains inert, but may be blown about like a seed with the
body as a parachute. If it land in favourable environment, rapid seg-
mentation and budding occur within the cyst, and a new Glyciphagus
emerges. M. Mégnin reports a case where myriads of these Acarids
appeared very inopportunely from their cysts in a preserved-meat manu-
factory, which some years previously had been used for the production
of bone buttons.

New Genus of Hydrachnids.t—Herr F. Koenike describes a new
genus of Hessian Hydrachnida, which he calls Teutonia primaria ; it
appears to be allied to Limnesia and Sperchon, and to connect these
genera with one another.

Accidental Parasitism on Man of Tyroglyphus farine.t—M. R.
Moniez deals with the occasional presence on Man of this common
Acarid. It was observed at Lille during the handling of wheat imported
from Russia and arriving in so dry a state that no kind of fermentation
could go on, so that there was no food for the mites. It is probable that
they were cast into the air, and so reached the skin, where their powerful
organs enabled them to pierce the skin and suck the fluids beneath.

Marine Acarina of the Coasts of France.$—M. Trouessart thinks
that the Acarina which are truly marine—the Halacaride—ought to
form a distinct family and not a subfamily of the Trombidide, as,
indeed, was proposed by Murray in 1875. The young appear to be
carnivorous and the adults herbivorous in habit. Like many other
Acarina, they are parasitic when young, and merely commensals when
adult. They thrive well in brackish water, and resist for a long time
the influence of fresh water. ‘They abound in the coralline zone. In
the monograph which M. Trouessart has in preparation seventeen
species will be described, while English naturalists have as yet only
reported the presence of ten on our coasts; several of them are, of
course, common to the two faune.

Marine Hydrachnida. ||--Dr. R. v. Schaub has some notes on the
generic and specific characters found in Pontarachna, and some observa-
tions on the well-known genus Midea He comes to the conclusion that
Asperia Lemani (Haller) is the female and Nesxa Kenikei (Haller) the
male of M. elliptica (Kcenike).

Morphology and Larve of Pantopoda. {—Herr G. Adlerz commu-
nicates some observations on the morphology and development of the
Pantopoda. The first part of his paper deals with the homologies cf

* Journ. Anat. et Physiol. (Robin), xxv. (1889) pp. 106-10 (1 fig.),

+ Zool. Anzeig., xii. (1889) pp. 103-4.

t~ Comptes Rendus, eviii. (1889) pp. 1026-7. § T.¢., pp. 1178-81.

|| SB. K. Akad. Wiss. Wien, xeviii. (1889) pp. 163-79 (2 pls.).

{| Bihang K. Svenska Vet. Akad. Handlingar, xiii. No. iv. (1888) 25 pp. (2 pls.).
1889. 2N

510 SUMMARY OF CURRENT RESEARCHES RELATING TO

the appendages, with special reference to those of Nymphon strémii and
Phoxichilidium femoratum. In a second chapter the author discusses the
larval stages of the last-named species.

e. Crustacea.

Development of Amphipoda.*—Madlle. M. Rossiiskaya has studied
the development of Orchestia littorea. The egg, which is deep-violet in
colour, and oval in form, is covered by a single membrane, the chorion.
The first two blastomeres differ slightly in size, and the later segments
are still more unequal. Segmentation stops when thirty-two blastemeres
have been formed; protoplasm is then detached from the yolk in the
form of amceboid cells, which become scattered over the whole surface
of the egg. The blastoderm is formed by the approximation of from
four to ten cells, which contract their pseudopodia, become polyhedral,
and form a small, irregular, white spot. Around this, cells elongate and
become divided in the direction of the radii of a circle, whose centre is
the blastodermic spot. Although the cells on the dorsal surface multiply,
their number does not increase; this shows that they migrate to the
ventral surface, where they aid in enlarging the blastodermie spot.

After the blastoderm has completely covered the ventral surface it
elongates at one pole much more rapidly than at the other; the former
of these poles is the oral, and the other the aboral. At last the whole
surface of the egg is covered by the blastoderm.

During the formation of the endoderm, very interesting sections
were obtained; these showed that each blastodermic cell of the ventral
surface consists of two parts; the external portion has a condensed pro-
toplasm which stains well, while the internal part stains feebly, and
seems to contain yolk; in several of these cells there are two nuclei.
These sections show exactly the mode in which nutrient matter is taken
in. When the blastoderm covers about two-thirds of the surface of the
egg, a dorsal organ is formed on one of its sides; this has the appearance
of a funnel, and is made up of large pyriform cells with large nuclei.
When the blastoderm completely envelopes the nutrient yolk, it secretes
the larval tissue, which is very delicate, transparent, and structureless.

As in Oniscus murarius, the endodermic cells arise from a small part
of the blastoderm. When the dorsal organ has taken up its definite
position on the median line of the dorsal surface, the endodermice cells,
which, till now, have been multiplying in the interior of the yolk,
migrate towards its surface, and form two lateral bands, which are
applied against the abdomen; these bands are the walls of the mid-
intestine. Shortly after the intestinal tube is completely closed, the
cells which form it change in appearance ; instead of being flattened and
solid they become large, prismatic, and so charged with vacuoles that
the protoplasm only forms a delicate layer on their walls. There then
appear three grooves, two of which are dorsal and one ventral; the
former cut off, so to say, the true intestine from the intestinal sac, the
latter divides the rest of the intestinal tube into two hepatic sacs.

The gonads are formed thus; in the dorsal wall of the intestine, at
the two lateral points at which they touch the hepatic sacs, the epithelial
cells become cylindrical in form, and multiply rapidly ; the cells of the
hepatic sacs, where they touch the intestine, simultaneously undergo the
same changes. ‘Thus there are formed two solid masses of cells, placed

* Bull. Soc. Imp. Nat., 1888 (1889) pp. 561-81 (2 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. Hil

on either side of the intestine. These become hollow, and separate
from the walls which produced them.

The mesoderm is first formed from the inner cells of paired ecto-
dermic swellings. The nervous system commences with the formation
of cephalic ganglia on either side of the head; the ganglia of the
ventral chain appear as paired ectodermic thickenings.

Madlle. (Dr.) 8. Pereyaslawzewa* describes the development of
Caprella ferow. The ova have a transparent but very compact chorion,
which does not allow of the passage of much colouring matter or pre-
servative fluid. The nucleus, which is placed at the centre of the egg,
is surrounded by a thick layer of protoplasm (formative yolk), covered
by a layer of nutrient material, which contains a number of fat-drops.
After the seventh stage, the segmentation loses its regularity, and
becomes more and more difficult to study ; as the formation of the blasto-
derm is being completed, it thickens on the ventral surface along the
median line, while remaining more delicate elsewhere. When its for-
mation is completed, and it covers the dorsal surface of the embryo, the
boundaries of the cells are no longer recognizable, and the blastodermic
layer has the form of a mass of transparent, perfectly clear, bodies,
which envelope and close the yolk, As the dorsal organ is being
formed, a transverse groove appears on the ventral surface, which
carries down the blastoderm into the midst of the vitelline masses ; this
is the commencement of the abdomen. Simultaneously two lateral
prominences appear above the dorsal organ; these represent the two
halves of the head, which, therefore, are at first separate from one
another. The development of the body occupies fifteen days.

In the course of the growth of the blastoderm, the constituent cells
divide in two directions, radial and tangential; the thickest cells of the
ectoderm are found in the thickenings which go to form the extremities,
and in the ganglia of the ventral chain. The stomodeum is developed
shortly before the rectum; both are developed in exactly the same way
as in Gammarus. ‘lhe formation of the mesoderm coincides with that
of the extremities ; at first its elements accumulate in the ectodermal
swellings which have given rise to them. In the phases which corre-
spond to this period of development, the mesoderm nowhere forms an
intermediary layer between the ecto- and endoderm. Later on, the
division of the mesodermic cells becomes very active, they pass the
boundaries of the cavities of the swellings, and become collected in
places where muscles will be formed. Before, however, these appear,
the heart begins to be developed, and as it is developed the dorsal organ
disappears.

In describing the development of the endoderm and its derivates, it
is pointed out that the hepatic appendages are developed from endo-
dermal cells which form two independent tubes.

British Amphipoda.} —In the first of his notes on British Amphipoda
the Rev. Dr. A. M. Norman describes a new genus and some Cidiceride.
The former, which is called Megaluropus, is remarkable for the large
round eye which is situated on a greatly projected head-lobe, and the
expanded foliaceous branches of the last uropods. It appears to be
nearly allied to Elasmopus. The new species, M. agilis, has been taken

* Bull. Soc. Imp. Nat., 1888 (1889) pp. 582-97 (2 pls.),
+ Ann. and Mag. Nat. Hist., iii. (1889) pp. 445-60 (3 pls.

ny
2 NF

512 SUMMARY OF CURRENT RESEAROHES RELATING TO

in the Firth of Clyde, Liverpool Bay, Devonshire coast, Jersey, and
Firth of Forth ; it is most frequently taken by means of the surface-net
at night, and is a very active swimmer. ;

The Cidiceride noticed belong to the genera Monoculodes, Hali-
medon, and Aceros; Aceros phyllonyx was taken sixty mules north of
Peterhead, in 69 fathoms; it may be distinguished from all other
British Cidiceride by the total absence of a rostrum, and also from
Halimedon, which it most closely approaches in the form of the gnatho-
pods, by the structure of the antennules, which, in the female, have a
remarkably long peduncle.

Amphipod Family of Scinide.*—Prof. C. Chun finds that the
Amphipoda of Stebbing’s family Scinide (Tyronide of Bovallius, and
Fortunate of Chun) are pelagic animals which only exceptionally come
to the surface in warmer zones ; their reduced eyes show that they are
adapted to live in imperfectly illuminated regions. But little has been
till lately known about their organization, and their place in systematic
classifications is open to revision. Prof. Chun would form six sub-
orders of the Amphipoda :—1, Caprellidea ; 2, Crevettina ; 3, Synopidea ;
4, Amphipoda Gammaroidea, with the families Lanceolide and Vibilide ;
5, Tyronide, with the family Scinide; and 6, Hyperine, with the
three tribes Hyperide, Phronimide, and Platyscelide. In the
Tyronide the body is not compressed, the head small, the eyes small
or rudimentary; the upper antenne have no secondary flagellum ;
basal joint of flagellum very large, sword- or lancet-shaped. Lower
antenn: rudimentary in females, mandibles and maxillipeds without
palps, &e.

Ostracoda of North Atlantic and North-western Europe.{— Prof. G.
S. Brady and Canon A. M. Norman have issued a monograph of the
marine and fresh-water Ostracoda of these districts; the present memoir
treats only of the Podocopa, and is intended to supplement Prof. Brady’s
well-known monograph of the recent British Ostracoda.}

Parasitic Crustacea.§S—MM. A. Giard and J. Bonnier have a note
on an Epicarid parasitic on an Amphipod, and on a Copepod parasitic on
an Epicarid. The Epicarid was found parasitic on Ampelisca diadema,
whence two specimens were taken. They belong to the group of
Cryptoniscina, and were both females with young. ‘The whole body is
converted into a vast incubatory chamber, closed by two lateral plates
which extend from the first to the fifth thoracic segment; they are
united along the middle line so as to leave only an aperture at either
end for the passage of water. On the dorsal side are five metameric
bands, corresponding to the first five thoracic somites; on either side of
the body, on each of the wings, there are conical eminences, which are
probably the vestiges of limbs. On the head the maxillipeds are alone
well developed.

The terminal part of the body is curved towards the rest in such
a way as to complete the incubatory chamber by a posterior cavity, which
is likewise filled with eggs. This curious parasite is called Podascon
della Vallei, a new genus being requisite for its reception.

* Zool. Anzeig., xii. (1889) pp. 286-90, 308-12.

+ Sci. Trans. R. Dublin Soc., iv. (1889) pp. 63-270 (16 pls.).
+ See Trans. Linn. Soc. Lond., 1868.

§ Comptes Rendus, eviii. (1889) pp. 902-5.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 513

On a specimen of Aspidophryxus peltatus the authors have found the
females and two males of a very singular Copepod, which they call
Aspidecia Normani. The female has the form of a miniature Sacculina ;
it is fixed to the Mysis on which the Aspidophryxus is parasitic by a
short peduncle, which ends in a sucker, and to the parasite by an
elongated cord; on this cord the male was found. Towards the free
end of the body were two ovigerous sacs, containing eight to ten
segmenting eggs. ‘T'he males have a form somewhat similar to that of
the males of Sphexronella Leuckarti ; they are fixed by a spiral chitinous
filament secreted by cement-glands, and a large sucker allows the
parasite to apply its oral apparatus to its host. At the hinder end of
the body are two lateral lobes which contain the spermatophoral sacs.
This new genus appears to be closely allied to the Choniostoma mirabile
lately discovered by Hansen, and, with Spheronella, should be placed in
the aberrant family of the Choniostomatide.

Morphology and Systematic Position of the Dajide.*— MM. A.
Giard and J. Bonnier offer additional evidence in support of their view
that the Dajide are intermediate between the Cryptoniscina and the
Bopyrina. Dajus mysidis has five pairs of appendages, and the fifth
pair, which escaped the notice of Gerstaecker, are the best developed and
form the greater part of the incubatory cavity. The morphology of the
head and thorax differs little from that of the similar parts in the
Phryxina. The adult male presents the pleon which is characteristic
of Phryxus, but the antenne and rostrum forcibly recall the structure of
embryonic Cryptoniscina.

The study of Dajus simplifies that of Aspidophryxus ; the species lent
to the authors by Dr. Norman had been determined as A. peltatus by
G. O. Sars; but it appears to be distinct from that species and may be
called A. Sarsi; the ditferences between the two species are minutely
pointed out. Certain errors in Sars’s original description are so noted,
and the correction of them shows that Aspidophryxus is more closely
allied to Dajus than could previously have been imagined.

Tegumentary Coverings of Anatifer and Pollicipes.;—M. R. Koehler
points out that the characteristic tegumentary coverings of Pollicipes
have a very complicated structure, and do not at all merit the name of
scales. The chitinous layer of the peduncle has on its surface a series
of conical depressions, clothed by a membrane which is continuous with
the general cuticle which covers the chitinous layer. This membrane
does not, however, stop at the edge of the pit; it is prolonged freely,
and forms a kind of cupola, the internal region of which is placed in the
layer of chitin and exhibits very elegant longitudinal and transverse
striz, while the outer half has a uniform dark-brown coloration. The
internal region contains a rounded concretion which effervesces with
acids. The external region is occupied by a whitish mass which com-
pletely fills the cavity of the cupola; it is limited internally by a very
fine membrane, which fuses with the cuticular layer. It is the whitish
mass which gives the white colour to these so-called scales, while their
edges are nothing else than the external borders of the cupola. At the
base of each cupola there is a rounded orifice which is bounded by a
slightly swollen edge; the edges are continuous with a tube, the wall of

* Comptes Rendus, cviii. (1889) pp. 1020-2. t T.c., pp. 755-7,

514 SUMMARY OF CURRENT RESEARCHES RELATING TO

which is always formed by the same cuticle as that of the wall of the
cupola. These tubes traverse the chitinous layer, becoming more
delicate as they approach its internal surface, but their lumen always
remains perfectly distinct; they take a slightly sinuous course. It
is by these tubes that the cupole receive the nutrient materials
which they require.

The chitinous layer of the peduncle of Anatifer has no special
covering, but the cuticle-membrane has certain thickenings which, to
some extent, recall the arrangements which are observed in Pollicipes.
These are hemispherical swellings with globules differentiated in their
interior ; these latter are formed by the cuticle, and are received into
pits of the chitinous layer. The formations are more complicated m
Pollicipes, but in both genera they are continuous with similar fibres
which traverse the subjacent chitinous layer in radiate fashion. The
structure of the calcareous valves of the capitulum also presents some
peculiarities in Pollicipes, for the valves are of considerable thickness,
and the calcareous plates are divided into three or four strata by
secondary layers of the cuticle. The general tissue of the plates is not
compact as in other genera, but contains numerous lacune, which are
absolutely empty.

Vermes.
a. Annelida.

Influence of Nervous System of Annelids on Symmetry of the
Body.*—M. L. Roule, who has studied the development of various
Annelids, and especially of the Enchytrxidx, attempts a sketch of the
development of the nervous system. The nervous centres are of
epiblastic origin, and the first is the cephalic or frontal plate; it alone
exists in those embryos in which the development is condensed, but it is
not so with larve. These latter also have a subepiblastic nervous
plexus which is chiefly placed under the vibratile oral corona; it some-
times, as in Lopadorhynchus, becomes a compact ring. We have here a
radially symmetrically nervous system, and the embryos are oval or
spherical. The annular plexus is peculiar to the larva, aud disappears
after the larval stage. The body next elongates and a third nervous
rudiment arises in the metasoma; this is the future ventral nerve-cord.

At their first appearance the plates are merely local proliferations of
the ectoblast, which are thicker in the centre than at the sides. Changes
occur when the mesoblast begins to be developed, for this elongates with .
the growth of the body, and the primitive radial symmetry is converted
into the bilateral, which is preserved in the adult; the rudiments of the
nervous centres are modified to follow this change of symmetry. Two
chief centres of proliferation appear in each of the cephalic and medullary
plates, and are arranged symmetrically around the new longitudinal
axis which divides the body into two halves.

In the primitive types the medullary cords inclose, for the whole of
their extent, an equal number of nerve-cells and fibrils, while in the
higher types there is a differentiation into ganglia formed of cells only
and of connective fibrils. The author cannot regard the phenomenon of
the production of the metasoma by the prosoma as similar to an alterna-
tion of generation, as does Kleinenberg. Nor, as ke will show in a

* Comptes Rendus, eviii. (1889) pp. 359-61.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. ais

more extended memoir, can he accept the views of the just-mentioned
naturalist or those of Sedgwick as to the relations between Meduse and
Annelids.

Epidermis of Serpulide.‘—WM. A. Soulier has had some difficulty in
examining the structure of the epidermis in these worms. The cells are
not sharply distinguished, and they vary in the degree to which they
stain, while it often happens that they become retracted. Like Claparéde
he is able to distinguish a true epidermis from a hypodermis; in the
former are numerous alveoli, some of which are found empty, while
others are filled with granulations or a homogeneous liquid which stains
intensely. These alveoli elaborate the mucus; they are surrounded by
fibro-cells which stain less intensely. The hypodermis has a similar
constitution; in certain cases it increases in thickness and forms
swellings. Myzicola secretes a very thick tube in a few minutes, owing
to the large number of these swellings which it possesses. The author
is of opinion that the supporting and the muciferous fibro-cells of the
epidermis of the Serpulide have their origin in the hypodermis, and
that they are merely differentiated connective cells.

Marine Oligocheta of Plymouth.t— Mr. F. E. Beddard states that
there are three species of Oligocheta common in the Sound at Plymouth,
which are apparently identical with certain forms described by
Claparéde from the shores of Scotland and France. One belongs to the
genus Pachydrilus, and the two others are Clitellio arenarius and C.
ater. Tubifex lineatus has been stated to occur at Plymouth, but this
is a most mysterious species, Hoffmeister’s original description not
rendering its identification possible.

Australian Earthworms.{—In his fifth communication on this sub-
ject Mr. J. J. Fletcher describes twenty new species of earthworms,
chiefly from New South Wales, but there are a few from Queensland and
South Australia. They belong to the genera Megascolides, Perissogaster,
Digaster, Pericheta, and Cryptodrilus; of the last there are eleven
species. At present it would be premature to separate any as types of
new genera, though it is obvious that that will have to be done, so
remarkable are the characters of some of the species. Some fifty species
of Australian earthworms are now known, but three or four times as
many probably remain to be discovered. It cannot yet be certainly said
that the interesting morphological points detailed by Prof. Baldwin
Spencer in his recent memoir on Megascolides australis will be found to
be of equal systematic value.

Green Cells in Integument of Aeolosoma tenebrarum.$S—Mr. F. E.
Beddard describes the green-coloured spots of this worm as large cells
with a thin peripheral layer of protoplasm containing a nucleus ; in the
centre is a large giobule of oily appearance impregnated with the colour-
ing matter; treatment with various reagents seems to show that this
green pigment is not chlorophyll. The author suggests that it belongs
to the class of respiratory pigments, with a number of which he com-
pares it, and it seems also to be of value as a means of protection.”

* Comptes Rendus, eviii. (1889) pp. 460-3.

¢ Journ. Marine Biol. Assoc., i. (1889) pp. 69-71.
¢ Proc. Linn. Soc. N.S.W., iii. (1889) pp. 1521-58.
§ Proe. Zool. Soc., 1889, pp. 51-6 (1 pl.).

‘

516 SUMMARY OF OURRENT RESEARCHES RELATING TO

Anatomy of Hirudinea.*—Mr. C. O. Whitman has a preliminary
notice of some new facts about the Hirudinea. As a group, they are
characterized by the possession of segmental organs on the first ring of
every somite. The diffuse or non-metameric arrangement which is seen
in Nephelis and some other forms seems to have been acquired
secondarily. ‘The author has shown that in all ten-eyed leeches the
eyes represent enlarged, more or less modified, segmental sense-organs ;
if this be true of other leeches, it would appear that the metameric
sense-organs are earlier in origin than the non-metameric. In two.
species of Clepsine it has been seen that the segmental sense-organs
appear very early in the embryo, before the time of hatching, while the
scattered organs arise later. ‘The labial sense-organs are serially homo-
logous with ventral sense-organs, as the author will soon show. Mr.
Whitman’s experience leads him to think that “ most of our reputed
blind leeches will yet be made to bear testimony to the blindness of their
observers.” Inanew Japanese marine leech, Branchelliopsis, eyes appear
to be altogether wanting, but very careful search revealed the presence
of at least two pairs of eyes. They have so little pigment that they
cannot be seen from the surface, but the visual cells are there. Another
new genus, Piscicolaria, from the smaller lakes of Wisconsin, comes
nearer to being blind than any leech yet examined; the only evidence of
an eye is a single large visual cell on either side of the head without a
trace of pigment-investment. The test of a leech eye is the presence of
visual cells; these are the large clear cells of Leydig; they always make
up the bulk of the eye, and in the Hirudo pattern they are the only cells
which are supplied by the optic nerve; their main axis is generally,
though not invariably, parallel with the axis of the eye; in Clepsine and
Branchelliopsis the nucleus lies on the side exposed to the light, the
clear rod-like part of the cell being directed towards the pigment; the
cells are practically inverted, the nerve-fibres entering at the nucleated
pole. The chief distinction between the different patterns of eye and
the typical sense-organ lies in the relative abundance of the clear
cells.

The segmental sense-organs are double, both in structure and fune-
tion; there is an axial cluster of elongated cells, terminating at the
surface in minute hairs, and probably representing a tactile organ.
Around and beneath the tactile cells are the large clear visual cells, so
characteristic of the eye. We have, therefore, a visual and a tactile
organ combined, both derived from a common mass of indifferent
epidermal cells, and both supplied by fibres from a common nerve-
branch. Incredible as the double nature of these organs may at first
appear, there is no escape when we once understand the structure of the
eye in Clepsine. Both the eyes and the segmental sense-organs develope
as local thickenings of the epidermis, and at first the cells are alike in
form, size, and structure; about the time the pigment begins to appear
the two sorts of sense-cells begin to show a difference in size, and an
indistinct boundary line appears between them.

It is urged that the metameric arrangement of the sense-organs of
the Hirudinea is a matter of more importance than the latest writer on
the subject—Apathy—appears to imagine. The key to the analytical
study of the external form is to be found in the metameric disposition

* Journal of Morphology, ii. (1889) pp. 586-99.

ZOOLOGY AND BOTANY, MICROSOOPY, ETO. 517

of the sense-organs. The terminal somites are of the highest importance
for specific diagnosis, and the annular composition, which offers so much
of theoretical interest, cannot be deciphered without the use of these
organs.

But the importance of the segmental character of the sense-organs
is not to be measured by its usefulness in systematic determinations ;
nowhere is a chapter in the evolution of sense-organs so perfectly pre-
served as among the Hirudinea. These segmental organs appear to be
identical with the lateral-line organs of Vertebrates, and it is suggested
that they have formed the starting point for the organs of special sense
in the higher animals, not excepting even the eyes of Vertebrates. Mr.
Whitman thinks that if we take what are now incontestable facts in the
phylogeny of annelid and arthropod sense-organs, and add to them the
evidence in favour of the common derivation of the vertebrate organs of
special sense, we shall not much longer be able to concede to the
visual organs of Vertebrates the position of isolation they have so long
held. In the study of this question we must remember that (1) verte-
brate sense-organs must be assumed to be derived from invertebrate
sense-organs, and the history of the latter must furnish clues to the
genesis of the former; (2) in the development of special senses visual
cells have made the widest departure from the primitive tactile cells;
(3) the medullary plate of the vertebrate is undoubtedly an enormous
extension of the ancestral invertebrate plate ; (4) sense-organs lying
originally outside the neural plate have probably, in consequence of this
extension of width, been brought within the medullary area; (5) the
ancestral segmental sense-organs were not limited to a single pair of
lateral lines, but there were several paired lines arranged symmetrically
on the dorso-lateral and ventro-lateral surfaces.

A careful analysis of the annular composition of the body of Clepsine
has enabled the author to find just twenty-six somites in front of the
caudal sucker. Adding seven for the sucker, we have thirty-three, so
that the number of somites determined by the external rings agrees
precisely with the number of ganglia in the ventral chain.

The nervous system of Branchelliopsis is exceptionally interesting
from the possession of veritable spinal ganglia; they are lodged in the
anterior (sensory) of the two spinal nerves of each somite at a short
distance from the ventral cord. A pair of colossal nerve-cells are found
between every two consecutive ganglia in the ventral cord of this leech.
They contain axial cells which undoubtedly correspond to the neuro-
chord cells of other Annelids and probably to the colossal nerve-fibres
of Amphioxus, Miiller’s fibres in Petromyzon, and Manthner’s fibres in
Teleosteans.

In Clepsine chelydrz the spinal nerves issue as three distinct roots,
the anterior of which unites with the middle to form one nerve, The
agreement in form and structure between Piscicolaria and the Japanese
Branchelliopsis is remarkable, for it is much closer than that between
the fresh-water Piscicola of Europe and marine leeches.

All the Hirudinea may be derived from a form in which the somite
consists of three rings; the author promises to explain in an early paper
how these rings may become 4, 5, 6, or 12. Copulation in Clepsine
is never direct, that is, by union of sexual pores; as in Nephelis and
Peripatus, the spermatozoa are transmitted in spermatophores which are
planted on any part of the exterior, preferably on the back. The

518 SUMMARY OF CURRENT RESEARCHES RELATING TO

gradual contraction of the sperm-case forces the contents through the
skin in a steady stream, which can be seen under a magnifying power of
twenty diameters.

Reproductive Organ of Phascolosoma Gouldii*—Mr. HE. A.
Andrews has examined the reproductive organs of this Gephyrean.
There is a single reproductive organ, made up of a solid mass of germ-
cells supported by a structureless lamella projecting horizontally from
between the retractor muscle-fibres and the enveloping peritoneal mem-
brane; it is invested by a delicate nucleated membrane. Branches of
the supporting lamella extend into the chief lobes of the organ, and are
accompanied by elongated nuclei, similar to those of the peritoneal
membrane. The germ nuclei have quite different staining properties
from these nuclei; they increase in size towards the distal or free ends
of the lobes of the organ, where they are surrounded by protoplasm ;
this acquires definite cell-walls before the cells thus formed break loose
from the others into the celom. In this last various stages in the
growth of the ova, from the naked cells, 24 » in diameter, to the
apparently mature, 185 » in diameter, were observed. An ovum in
which the yolk measures 151 p had a vitelline membrane 3 yp thick
perforated by innumerable pores, through which delicate pseudopodia-
like processes pass out into an outer gelatinous case 12 yp, thick.

The reproductive organ of P. Gouldii is probably to be regarded as
a thickened fold of the peritoneum supported by a structureless basement
membrane or lamella; the nuclei of the peritoneum multiply rapidly to
form a mass of germ nuclei, which, on the surface of the mass, acquire
considerable cell-protoplasm; they are then forced out from the ends of
finger-like processes into the ccelom by the growth of more deeply
lying cells; the investing membranous part of the original peritoneum
is ruptured at its ends, when this occurs.

B. Nemathelminthes.

Coffee-Nematode of Brazil.t—Dr. E. A. Goldi has a note on Meloi-
dogyne exigua, the nematode which has for nearly twenty years been the
cause of disease in the coffee-plantations of Brazil. The females are
found to form cysts in swellings on the plants, and their vegetative
organs are reduced, while their ovary is so swollen as to make the
recognition of the vermian nature of the formless sack a matter of diffi-
culty. The ova, which are 0°085 mm. long, have a transparent, thick
and resisting membrane. The young are transparent, colourless, and
cylindrical, the aboral end being drawn out to a long, fine point; at the
terminal end of the esophagus there is a spherical, muscular swelling.
The adults are more club-shaped in form, the aboral end being thicker
than the oral, and ending ina sharp spine. A great deal remains to be
discovered with regard to the discrimination of the sexes, the manner in
which encystation is effected, and the wanderings of the young.

Physaloptera.{—Prof. M. Stossich gives an account of the general
characters, the constituent species, and the distribution of the Nematode
genus Plhysaloptera Rudolphi. Twenty-eight certain species already
recorded are diagnosed, and notice is taken of nine others insufficiently

* Zool. Anzeig., xii. (1889) pp. 140-2. + Zool. Jahrb., iv. (1889) pp. 262-7.
{ Bull. Soe. Adriat. Sci. Nat., xi. (1889) pp. 36-59 (3 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 519

known. The hosts comprise over a hundred reptiles, birds, and
mammals, .

Female Genital Ducts of Acanthocephala.*—Herr P. Kniipffer
corroborates the observations of Saefftigen on this subject. Indepen-
dently of the latter, he demonstrated that the oviduct, described by
Leuckart as single, is really double. The muscular structure or
“ Glocke ” which receives the embryos from the body-cavity, the double
ducts which are continuous with the former, the so-called “uterus” in
which the ducts merge, the muscular and glandular terminal portion or
“vagina,” are described and figured. Kniipffer’s researches included
Echinorhyncus heruca Rud., E. polymorphus Bremser, E. globulosus Rud.,
E. strumosus Rud., E. pseudosegmentatus n. sp., which are all separately
discussed. The author contributes some notes on the body-wall and the
musculature, and denies the legitimacy of the genus Paradowites, which
Lindemann sought to establish as distinct.

y. Platyhelminthes.

Gunda ulve.j—Herr A. Wendt is of opinion that the Planaria
ulve of Oersted should be placed in the genus Gunda; the chief cause
for this change lies in the close resemblance exhibited by the terminal
organs of its generative apparatus to that of G. segmentata; the course
taken by the oviducts, their union, and the opening of the unpaired
oviduct into the uterine duct. In most fresh-water Planarians the uterus
lies between the pharyngeal pouch and the penis, but in Gunda the penis
is near the pharynx and the uterus is placed further back. Close
similarity is also to be detected in the arrangement of the central
nervous system.

On the other hand, the gonads do not in G. ulve exhibit the same
marked segmental arrangement as in G. segmentata; before, however,
judgment is passed on this point a larger number of marine Planarians
must be examined.

Nervous System of Nemertines.t—Herr O. Biirger has a pre-
liminary communication on the nervous system of Nemertines. On the
whole he confirms the observations of Hubrecht. He has succeeded in
discovering an anal commissure of the lateral nerves in Cerebratulus.
The cesophageal nerve-trunks (vagus of Hubrecht) of that worm, of
Langia, and of Polia are connected by a strong commissure, which con-
tains ganglionic cells. The proboscis of Schizo- and Paleo-nemertinea
is innervated by two ascending nerves given off from the ventral
ganglion, which form a layer around a muscular zone. In the Hoplo-
nemertinea ten to seventeen cords enter the proboscis, where their course
is constant; they are connected by transverse fibrous bands, which sepa-
rate the longitudinal musculature into two concentric layers. In the
body there is an inner layer between the circular and internal longi-
tudinal musculature, in addition to the peripheral nervous layer. Besides
the already known sensory organs, the author found an altogether ter-
minal epithelial invagination on the head, to which a nerve passes. The
lateral cephalic pits of the Hoplonemertinea are provided with sensory
cells which carry rods.

* Mém. Acad. Imp. Sci. St. Pétersb., xxxvi. (1888) pp. 18 (2 pls.).
+ Arch. f. Naturgesch., liv. (1889) pp. 252-74 (2 pls.).
} Nachr. K. Gesell. Wiss. Gottingen, 1888, pp. 479-82.

520 SUMMARY OF CURRENT RESEARCHES RELATING TO

The histological characters of the central nervous system have been
specially investigated ; it contains ganglionic cells and fibrillar substance,
and a highly differentiated connective tissue. All the ganglionic cells
are unipolar and devoid of membrane, and lie in sheaths of connective
tissue. They are (1) cells with poorly developed body, darkly coloured,
highly refractive nuclei, small and irregular in form; or (2) small,
elongated, club-shaped cells, with oval nuclei and one or more nucleoli ;
or (3) they are large, lightly coloured, flask-shaped, with large round
nucleus and one nucleolus; or (4) they are colossal cells, which quickly
take up colouring matters, and have a round nucleus with a projecting,
large nucleolus.

The connective tissue is of two types; one is like the neurilemma,
while the other consists of fibres which are given off from numerous,
dendritically-branched processes of membraneless cells; they surround
in large numbers the ganglionic cells, and may be easily recognized by
their large oval nucleus and their peripheral zone of granules.

Helminthological Notes.*—Dr. von Linstow has another of his
papers on new and imperfectly known worms. He has made an ex-
amination of the internal structure of Pseudalius minor, taken from
various organs in the common Porpoise. Physaloptera preputialis sp. n.
was found in Brazil in Felis catus; it is chiefly remarkable for, the
preputium-like duplication of the skin at the caudal end of the body in
both sexes. Tr. campanula sp. n. is from the domestic cat of Brazil ; it
is possible that this is the same as the form which Diesing named
Tr. felis, but did not describe.

Echinorhyncus Dipsadis sp. nu. was found represented by fifteen
examples in the enteric wall of a large Dipsas Blaudingi from the
Cameroons, where it lived in its larval condition; encapsuled Hchino-
rhyncus-larvee have been found in a number of snakes; their adult forms
are probably to be sought for in birds of prey.

Cercaria terricola sp. u. was found in the liver of Helix ? vermiculata
from Algiers, and C. terrestris sp. n. from the same organ in H. lens from
Greece. The author concludes with some remarks on the anatomy of
Bothriocephalus rugosus ; this species may be as much as 380 mm. long.
The muscles of the parenchyma are well developed, but those of the
subcuticular layer are very feeble. Of the former the longitudinal
muscles are the best developed. The nervous system consists of two
ganglia connected by a strong transverse commissure, and of two strong
longitudinal nerves invested in a sheath. Outside the nerve-trunks there
are ten vascular trunks, which are 0-016 mm. broad. On the whole, this
species of Bothriocephalus is very different from B. latus, and recalls
rather the Teenie of Birds.

Herr G. Brandes} gives an account of a very small Distomum
(D. claviforme sp. nu.) which he found in large numbers in the rectum of
Tringa alpina. Its body is divided into a longer flat anterior portion
and a shorter spherical hinder part; the latter contains the generative
apparatus. Another new species was found in the small intestine of the
frog; it is 2°5 mm. long, and it is to be called D. turgidum. The author
concludes with some notes on D. heteroporum from Vespertilio pipistrellus,
which seems to have been somewhat misunderstood by Van Beneden.

* Arch. f. Naturgesch., liv. (1889) pp. 235-46 (1 pl.).
+ T.c., pp. 247-51 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. AO

Prof. M. Stossich * continues his helminthological researches, de-
scribing seven new species of Distomum, of which six are figured.
Several other species of Distomum are discussed, and the occurrence of
some other parasites (Tenia botrioplitis, Ascaris ensicaudata, &c.) is
recorded.

The Species of Distomum in Amphibians.t—Prof. M. Stossich
describes 16 species of Distomum parasitic in Amphibians, and seven
others somewhat doubtful. <A list of 24 Amphibian hosts with their
known Distomum parasites is furnished ; in Rana temporaria nine species
occur, in R. esculenta ten.

Anatomy of Phylline Hendorfiij—Dr. von Linstow gives an
account of the anatomy of this new species of ectoparasitic Trematode,
which was found on the scales of Coryphena hippurus. The body is
ovate in form, 8°7 mm. long, and 5*2 mm. broad; at the anterior end
there are two suckers, and at the hinder end one which is very large.
The former are attached to the body in such a way that their hinder and
lateral margins are free; the latter, which is 3-1 mm. broad, carries
three pairs of hooks ; there are two stiff supporting lamelle, which
obviously prevent the suckers from being torn off. All the three
sucking dises consist of a cuticle, which is much stronger on the dorsal
than on the ventral surface, and of a well-developed dorsoventral
muscular mass, in which separate cells are imbedded ; the parenchyma
is feebly developed, is fibrous, and contains no nuclei. The three pairs
of hooks vary a good deal in structure ; the most anterior pair is sur-
rounded by two tendons which lie in a sheath where they can work
backwards and forwards. While the hooks of most Trematodes and
Cestodes are organs which serve for attachment, those of this form are
clearly organs which are adapted to loose the parasite from its place of
attachment ; the median long hooks have the function of surrounding
the free margin of a fish’s scale. These hooks are of a horny nature

The cuticle consists of a plexiform fundamental tissue, the spaces in
which are filled by rods of various sizes, better developed on the dorsal
than on the ventral surface, and giving a villous appearance. In the
dorsal cuticle there are also numerous rounded glands, which probably
secrete mucus. ‘The muscles of the cortical layer must be distinguished
from those of the parenchyma; they are either longitudinal, circular, or
diagonal in direction. The muscles of the parenchyma are uncommonly
strong, and are remarkable for passing through the testes, ovary, and
shell-gland.

The mouth is a large, almost spherical organ, 0:78 mm. in diameter ;
while it is well developed, the intestine is very feeble, and we must
suppose, therefore, that the ingestion of food requires much greater
strength than its propulsion and absorption. A rich vascular system
traverses the whole body ; it is formed of two large longitudinal trunks
which divide the body into three nearly equal thirds; posteriorly they
unite to form a cylindrical pulsatory vesicle which is covered by the
posterior sucking disc, and opens by a foramen caudale. Anteriorly they
widen out into large vesicles which vary considerably in their condition
of contraction ; one is almost always much larger than the other, and both

* Boll. Soc. Adriat. Sci. Nat., xi. (1889) pp. 23-30 (2 pls.).
+ T.c, pp. 60-74.
¢ Archiv f. Mikr. Anat., xxxiii. (1889) pp. 163-80 (2 pls.).

522 SUMMARY OF CURRENT RESEARCHES RELATING TO

open bya small cleft outwards. Secondary are given off from the primary
trunks, and all the trunks form anastomoses with one another.

The brain has the form of a kidney-shaped group of ganglionie cells
which lies just above the mouth; four ocelli may be noticed in it; a
second group of cells lying just behind the mouth may be called the
cesophageal ganglion. Four to six nerves are given off anteriorly from
the brain; four nerves run along the ventral surface of the body; these
nerves are easily recognized in stained transverse sections of the body ;
a third pair of nerves, which are much thinner, are placed on the dorsal
surface. In the middle of the brain lie four ocelli; each of these con-
sists of a spherical lens surrounded by a layer of pigment; on the free
‘side of each is a small highly refractive spherule which, possibly, acts
like the condenser of a Microscope. These ocelli are remarkable for
lying not in the cuticle, but in the centre of the brain, so that they are
covered externally by a layer 0:14 mm. thick. It seems clear, therefore,
that they cannot have the function of recognizing images, but can only
be able to distinguish light from darkness, as is the case with the eyes
of various Vertebrates which are covered by the skin.

The body-parenchyma, which stains feebly, is not cellular in structure,
but consists of a fine fibrous ground-substance, in which are rounded or
angular nuclei, 0-02 mm. in size. There is one ovary, and a pair of
testicles ; the seminal vesicle has very strong walls; the cirrus is large
and spindle-shaped, and lies to the left of, and just beneath the mouth.
The ovary is rounded, and is placed just in front of the testes; super-
ficially the two organs are very much alike. The vitellaria are very
widely distributed in the body, and lie in a dorsal and a ventral plane ;
the ootyp is spindle-shaped, and in it there is always found only one
egg. The shell-cland is of great extent, and consists of a large number
of pyriform glands with long efferent ducts. The ova are rhomboidal,
irregular, or triangular in form ; at the hinder end there is a filamentar
appendage of varying length. There is no canal of Laurer; a com-
parison of various forms shows that by this term, organs of various
functions are spoken of. Like the two other species of Phylline, the
development of P. Hendorfii is unknown; it is doubtless monogenetic,
and its embryos swim about in water by the aid of an investment of cilia.

The author points out the differences between the three species, and
concludes with enumerating the generic characters of Phylline.

Nervous System of Amphiptyches.*— Dr. F. 8. Monticelli has, in the
course of his researches on Amphiptyches, elucidated the nature of the
nervous system, which has hitherto been known only through a brief
notice by Wagener. It consists essentially of two lateral ganglionic
swellings, situated in the anterior portion of the body, and united by a
transverse commissure. Four nerves, two anterior and two posterior,
rise from the two ganglionic swellings. The whole system, of which the
details are described, lies rather towards the ventral surface. Morpho-
logically the system agrees with the general cestode type, and closely
resembles that of the simpler Cestodes, especially that described by
Lang in Amphilina foliacea Wagen.

Cercaria setifera.jt—Dr. F. 8. Monticelli has a preliminary notice
on a Cercaria with a long tail and lateral bristles, which occurs in the

* Zool. Anzeig., xii. (1889) pp. 142-4.
+ Bol. Soc. Nat. Napoli, ii. (1888) pp. 193-9.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 523

Gulf of Naples, sometimes free-swimming, but more frequently on
pelagic Ceelenterates, Tunicates, worms, and molluscs. He identities it
with Cercaria setifera Miller and with the Cercaria echinocerca of de
Filippi, and considers it as not improbably related to a form of Disto-
mum found in Beroé. The characteristics of the species are shortly
described.

Structure of Solenophorus.*—Signor C. Crety has particularly
devoted himself to the nervous system of S. megacephalus, in regard to
which the results of Moniez, Roboz, and Griesbach are not in agree-
ment. Two longitudinal nerves extend down the body; these are united
in a commissure and ganglionic centre in the head. The histology is
discussed, and the entire system regarded as closely resembling that of

Bothriocephalus latus as described by Niemiec.

5. Incertz Sedis.

Rotifers Parasitic in Sphagnum.t—Mr. W. Milne describes two
species of Rotifers found living inside the cells of Sphagnum, and thus
confirms observations made nearly forty years ago by Roeper and Morren.
These observers supposed the animal they saw to be Rotifer vulgaris,
but Mr. Milne designates what he observed as Macrotrachela roeperi sp. n.
and M. reclusa sp.n. In three different gatherings of the Sphagnum, at
considerable intervals of time, from the same locality, both species were
found abundantly. The observer believes the distribution of the rotifers
in the Sphagnum to be mainly effected by the external openings in the
cells, yet one of the forms observed forcing its way out took two or
three minutes to escape through the opening. In one case, two adults
and an egg were seen in the same cell, which was possibly the result of
a breakage between two adjacent cells. There is of course no real
parasitism, but the shelter afforded is doubtless advantageous.

American Rotifera.{—Dr. D. 8. Kellicott gives a partial list of the
Rotifera of Shiawassee river at Corunna, Michigan. From the brief
examination he was able to make, he was led to the conclusion that the
rotiferal fauna of inland America is abundant, and that the species are
largely identical with those of Europe, even to a greater degree than in
the case of Infusoria. The author adopts the classification of Hudson
and Gosse.

The new forms described are :—(1) Limnias shiawasseénsis ; it has
very much longer antenne then L. annulatus, and has different horny
processes and tube ; (2) Wcistes mucicola, which dwells in tubes made
in the mucilaginous matrix of the common Alga Gloiotricha pisum ;
(8) Callidina socials, found parasitic on the larva of the beetle Psephenus
Lecontei, has a corona which is relatively wider than that of C. parasitica,
and its antenna does not end in three lobes; and (4) Sacculus hyalinus
which is much smaller then 8S. viridis. In all, fifty species are
enumerated in this list, so the percentage of new forms is very small.

Tornaria in British Seas.S—Mr. G. C. Bourne gives an account of
the well-known pelagic larva of Balanoglossus, which was for the first

* Boll. Soc. Nat. Napoli, ii. (1888) pp. 124-30.
+ Proc. Phil. Soc. Glasgow, 1889, 6 pp. (1 pl.).
t Proc. Amer. Soc. Micr., x. (1888) pp. 84-96.
§ Journ. Marine Biol. Assoc., i. (1889) pp. 63-8 (2 pls.).

524 SUMMARY OF CURRENT RESEARCHES RELATING TO

time found last year in British Seas. Its discoverer was Mr. Weldon,
who was working at the Plymouth Laboratory.

The smallest larve were 0:33 mm. in length, and it would seem that
the posterior division of the gut is not a proctodeum, but that the
blastopore persists as the anus without being pushed further inwards by
a secondary invagination of ectoderm. In later stages all the characters
of a Tornaria were found exhibited. The anterior body, which is pro-
bably formed from the ameeboid cells found in the earlier larva, is
connected by a muscular thread with the now conspicuous apical sense-
organ. A perfect Tornaria was as much as a millimetre in length, but
individuals vary greatly in this respect. Hach ciliated cell is long and
columuar, slightly contracted in the middle of its length, and has a
large nucleus ; the cilia can be traced as fine fibrille inwards as far as
the nucleus, but the author was unable to determine whether or no
they entered it. The “heart,” as some authors call it, appears as a
vesicle lying just above and to one side of the proboscis pore.

The central portion of the apical sense-organ is composed of columnar
sense-cells bearing cilia; on it there are larger cells surrounding
a pair of deeply pigmented pits—the eye-spots of previous authors.
Beneath the sensory cells is a thin layer of nerve-fibres.

Specimens of the larve at later stages were never found, and it is
very probable that Tornaria ceases to lead a pelagic life, sinks to the
bottom, and undergoes its further development there.

Echinodermata.

Ludwig’s Echinodermata.*—Prof. H. Ludwig has issued another
part of his work ; the description of the calcareous bodies is continued
and completed. The general ground-form of these bodies is, in the
Dendrochirota, derived from an X-shaped rudiment, which has been
developed by the forking of the ends of a short rod. The same is true
of the “stools” of the Aspidochirota, and the four-armed calcareous
bodies of the Elasipoda and some Aspidochirota, as well as of the
fenestrated plates of the Molpadide, and the anchor-plates of the
Synaptide. The anchors of these last may be referable to the same
scheme, but the “ wheels” are more difficult to explain. Another kind
of calcareous body which is difficult to explain are the “tables” of the
Aspidochirota, which are symmetrically perforated, though there can be
little doubt but that they will be found to be derived from the bifureating
rod. Theangle at which this forking takes place is, as a rule, 120 degrees.
The concentrically striated bodies which are found in Trochostoma and
Ankyroderma appear to be special bodies, agreeing only with the rest in
that they consist of an inorganic substance.

The musculature of the bedy-wall and the histological characters of
muscle are next considered. In dealing with the nervous system Prof.
Ludwig gives a diagram to show the relations of the parts. The central
nervous system consists of a circular and of radial nerves. The peri-
pheral nerves derived from the former of these are the tentacular, the
integumentary nerves of the oral disc, and that of the pharynx ; with the
last the plexus on the stomach and on the small intestine may be con-
nected. ‘The peripheral nerves derived from the radial are those of the

* Byronn’s Klassen u. Ordnungen, ii. 3. Hchinodermata, by Dr. H. Ludwig,
Leipzig and Heidelberg, 1889, pp. 49-80 (pls. 1-5).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 525

foot-suckers, of the skin, of the muscles, of the nerves to the closing muscu-
lature of the cloaca, and of those to the mesentery of the hinder end of
the body. In the third place there are sensory or terminal organs. The
tentacular nerves serve the sensory plates of the tentacles of the Aspido-
and Dendrochirota, the bud-like sensory organs, and the tactile papille
of the tentacles of the Synaptide. The sensory cells of the skin are
innervated by the tegumentary nerves; those of the foot-suckers and
ambulacral papille by the nerves that go to them, while the tegumentary
nerves supply the tactile papille of the skin of the Synaptide and the
sensory cells of the skin. When auditory vesicles are present the radial
nerves give off auditory trunks.

Anatomy of Ophiuroids and Crinoids.*—Dr. O. Hamann continues
his account of the morphology of Echinoderms by treating of the
anatomy of Ophiuroids and Crinoids. In summarizing his results
generally he commences with the ambulacral nervous system; this is
found in all Echinoderms, lying, in Asterids and Crinoids, always in the
ectoderm, and in others in the cutis, where itis generally surrounded by
schizoccel spaces. In Crinoids the cesophageal ring is lost. The facts
that the ambulacral nerve-trunks of Ophiuroids are jointed, and that
there are ganglia in the dorsal as well as the ventral cells, are of great
importance. The ambulacral and mesodermal nervous system of the
Crinoids and its origin are next considered. This system consists of a
mesodermal pentagonal nerve-ring, and, in each arm, of two longitudinal
nerves, and the question arises, did these parts arise separately or is
their present condition a secondary one? The oral-mesodermal portion
is regarded as being derived from the ambulacral nervous system of
Crinoids, support for this view being found in the fact that the latter is
only preserved in rudiment in the epithelium; this ambulacral system
has no central organ, and the nerves in the epithelium are very poorly
developed as compared with the homologous nerves of other Echinoderms.
The ectodermal portion, therefore, has passed from the ectoderm into
the mesoderm, and its branches have been developed in the same way as
the peculiar nerves of Ophiurids, which arise at definite intervals from
the ambulacral nerves and form intervertebral nerve-branches. But
while the latter have retained connection with their point of origin, they
have lost it in the Crinoids, Further evidence in support of this view
is given by the agreement in structure which the three parts present.
In all three there are the same nerve-fibrils and ganglionic cells. While
there is no direct connection between the epithelial, ambulacral nervous
system and the other parts, there is such between the dorsal and ventral
portions.

The peripheral nervous system and the sensory organs are next
considered ; in the Crinoids there are nerve-endings in the epithelium
of the skin similar to those found in Asterids and Holothurians, as also
the sensory buds on the tentacles, which have been recognized by Jickeli
as sense-organs. In the Ophiurids, as the physiological investigations
of Preyer have conclusively shown, the peripheral nervous system is
exceedingly well developed; special sensory organs may be found in
large numbers on the tentacles of Ophiothri#, and the nerve-endings in
the epithelium are similar to those of Crinoids. In all groups there is
a nervous system in the epithelium of the enteric tract.

* Jenaische Zeitschr. f. Naturwiss., xxiii. (1889) pp. 233-388 (12 pls.).
1889. 20

526 SUMMARY OF CURRENT RESEARCHES RELATING TO

The water-vascular system has a similar character in all groups, but
the Crinoids have no madreporite, and their pore-canals do not open
directly into the stone-canal, but into superficially placed cavities of the
enterocel. The valvular arrangements of this system are of great
interest, but they are wanting in Ophiuroids and Crinoids, where they
are replaced by transversely disposed muscular fibres which traverse
the lumen of the vessels.

All the groups are provided with genital tubes; in Crinoids they
are placed in the arms, in Ophiuroids in the dorsal wall and in the
walls of the burse, and in Asteroids and Hchinoids in the dorsal wall
of the disc. The several groups present differences in the place of
maturation of the primordial germ-cells, for in Crinoids they ripen in
the pinnules, and in Ophiurids on the walls of the burs.

In addition to smooth and transversely striated muscular fibres, there
are in Ophiuroids peculiar obliquely striated fibres. Hpithelio-muscular
cells have been found in Holothurians, Asteroids, and Crinoids. The
musculature is partly of epithelial and partly of mesenchymatous origin.
The Crinoids are remarkable for spindle-shaped muscular fibres, which
are found in the arms as well as in the pinnules and cirri.

The glandular organ or so-called heart is not the central organ
of the blood-lacuna-system; muscular fibres are never found in its
walls. It is impossible to say at present what the function of this
organ is; the only thing which can be said with certainty is that
the organ has a glandular structure. The connection between it and
the genital tubes, which is to be seen in Asteroids and Crinoids, is of
significance.

With regard to the structures of the schizoccel, it is to be noted that
there is a very well developed cavitary system in Asteroids which has
the form of clefts and spaces in the connective substance; in the
Ophiuroids they are less extensive, and in the Crinoids they are repre-
sented by the longitudinal canals which lie beneath the ambulacral
nerves.

The author’s determination to deal with the phylogeny of the
Echinodermata has wavered as his work proceeded, for he has been led
to see of how subjective a nature such a representation is. Of one point
only is he firmly convinced, and that is, the Asterids are connected
with the Echinids, and that the latter may be derived from the former.
The Holothurians appear to be forms which have undergone degenera-
tion; many characters speak to their derivation from Hchinids; the
Crinoids seem to be the most highly organized forms, and with the
Ophiuroids form a group which have no specially close relation to the
others, save that they are all derived from an ancestor in which a
water-vascular system, a coelom, an ectodermal nervous system and
definite calcareous plates were already developed. With regard to
Semon’s recent attempt to map out the phylogeny of the group,
Dr. Hamann remarks that, in the present state of our knowledge of the
development of Echinoderms, it is too early to speak definitely of a
Pentactula-stage of a Pentactezea; nor does he think it correct to say
that there is such a stage in all groups, for the structures which have
been spoken of as one and the same stage are different, and show
undoubted modifications. Further objections are raised to the views of
Semon, and it is, in conclusion, suggested that weight should still be
attached to the homologies of the calcareous plates.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 527

Nervous System of Ophiurids.*—Dr. C. F. Jickeli has extended -
his observations on the nervous system of Echinoderms to Ophiurids.
If a number of sections of an arm be examined, four nervous systems
will be found extending in a longitudinal direction—there is the
ambulacral nerve of authors, which Dr. Jickeli proposes to speak of as
the ventral radial system; placed on this, and separated from it by a
structureless Jamella, is the paired ganglionic chain of Lange which it
is proposed to call the median radial system; on the dorsal wall of the
perihemal canal isa paired ganglionic chain, which may be distinguished
as the dorsal radial system. Two ganglionic chains lie between the
dorsal and ventral muscle on the external edge of the ambulacral plate ;
this is the lateral radial system.

The ventral radial system gives off on either side a nerve which
passes up the wall of the perihemal canal, and fuses with the neighbour-
ing cord of the dorsal radial system; a branch on either side, which is
continued laterally, gives off a branch into the muscle between the
adambulacral and basal plate, and breaks up within the former into
several branches; of these the innermost passes to the dorsal plate,
while the other branches enter an adambulacral papilla; this may be
called the adambulacral nerve. Belonging also to the ventral radial
system is a nerve on either side for the ambulacral pedicels; this forms
a subepithelial sheath around the whole pedicle, and becomes con-
solidated on its adoral side into a strong cord which is circular in trans-
verse section.

The median radial system gives off a branch on either side which
innervates the ventral interambulacral muscle, and another which,
like it, arises from a ganglion, and innervates the dorsal interambu-
lacral muscle. The dorsal radial system gives off branches on either
side, one of which ends in a ganglion of the lateral radial system,
another which becomes connected with the nerve for the ventral inter-
vertebral muscle, and others which unite with the dorsal. The three
pairs of ganglia of the dorsal radial system are connected by transverse
commissures, but the author could not find the one described by
Lange.

In all, each ambulacral segment has nine pairs of nerves; in the
formation of the oral ring, the ventral, median, and dorsal radial systems
take part, and this therefore consists of three different rings. In
addition to these, another is formed by the lateral system; as it lies
more externally than the others, it may be called the outer oral ring,
while the oral ring of previous authors is to be called the inner oral
ring. From this last the ventral ring gives off branches to each of the
two oral pedicels, and a strong branch, which, in its somewhat complex
course, gives off a number of branches ; all these are connected with the
corresponding branches of the adjoining rays. With them the bifurcate
branches of a third trunk become connected. The median and dorsal
rings combine to give a trunk which sends nerves to the adoral side of
the outer interradial muscle. Branches are given off dorsally from the
dorsal nerve-ring which appear to innervate the water-vascular ring
and the Polian vesicles. Strong nerves are given off at regular distances
to the “lips”; these appear to be processes from all the three systems
which compose the inner oral ring. No indications were seen of the

* Zool. Anzeig., xii. (i889) pp. 213-8.
202

528 SUMMARY OF CURRENT RESEARCHES RELATING TO

subepithelial enteric plexus, which has been made out by the author in
Crinoids and Asteroids.

Morphology of Crinoids.*—Dr. O. Hamann, in a preliminary com-
munication, deals with the nervous system of Crinoids. The epithelial
portion consists of the subepithelial plexus described by Ludwig and
others, and of the central cesophageal ring ; it corresponds to the ceso-
phageal ring and ambulacral nerves of other recent Echinoderms, which
are partly epithelial and partly mesodermal in position. In Crinoids the
epithelium of the ambulacral grooves is considerably thickened, and
consists of the same elements as in a starfish. In both there are epithelial
nerve-fibres with bi- and multipolar ganglionic cells; they have not
lost their connection with the epithelium of the body; this nervous
system has no central ring. The cpithelium of the grooves is made up
of sensory and supporting cells, and the processes of the latter traverse
the nerve-fibrous ring vertically. In each tentacle there is a nervous
band which innervates the sensory papille.

Another system of nerves is placed in the connective substance,
and to this belongs the fibrous mass placed around the chambered organ
with its nerve-trunks, which run along the dorsal side of the arm.
Another part of it is ventral in position, and has its own central organ.
The two portions of this mesodermal nervous system are connected with
one another. The ventral or oral part is divisible into a central organ,
an cesophageal ring, and the nerves given off from it; some of these
nerve-trunks have been described by Carpenter as a periambulacral
network. The nerve-fibrils of the ring have a concentric course, and
the number of nerves given off is very large. Some of these take a
dorsal or aboral direction and branch in the mesenteries and bands of
the ccelom, and on the organs that lie therein. Other nerves pass into
the circumoral tentacles. Those that are of the greatest interest are
those which enter into definite relations with the water-vessels; these
are, at first, five, and they bifurcate and pass into the oral body-wall of
the arms. Each water-vessel is accompanied on either side by a
nerye-trunk, so that they are twenty nerve-bands in the ten arms, to the
tips of which they may be traced. They likewise pass with the
branches of the water-vessels into the pinnule.

The dorsal or aboral portion of the mesodermal nervous system has
likewise a central organ, and the course of the fibres which compose it
is complicated. It gives off solid nerve-trunks into the arms, and never
hollow tubes as some observers have asserted. The trunks in the arms
give off branches from four opposite points ; some of these go to the flexor
muscles, and others, after much branching, to the dorsal epithelium.
Between every two groups of muscles, nerves pass out which go almost
directly to the oral body-wall, where they become connected with the
oral pair of longitudinal nerves which belong to the oral part of this
mesodermal nervous system.

Both the epithelially and mesodermally placed systems are com-
posed of very fine fibres, which generally run parallel and in cross
section appear dotted, and of ganglionic cells of various types. The
nerves of the cirri are regarded as special nerves; they are the only
vascular nerves found in Crinoids.

In addition to the sensory papille of the skin there are nerve-end-

* Nacbr. K. Gesell. Wiss. Gottingen, 1888, pp. 127-31.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 529

organs scattered over the whole surface of the arms and disc; these are
made up of epithelial groove-cells.

The author regards the presence of two nervous systems as, in con-
junction with the other structural characters of Crinoids, indicating
that this is the most highly developed group of Echinoderms.

Large Starfish.*—Prof. F. Jeffrey Bell describes a remarkably
large specimen of Luidia Savignii from Mauritius, which has nine arms,
none of which are injured or bear signs of having been repaired during
life. The disc is 95 mm. in diameter, and the longest arms measure
370 mm., and the shortest 350 mm., so that the span is about 27 inches.

Variation in Ophiura panamensis and 0. teres.,—Mr. J. E. Ives
has an interesting note on the variations exhibited by examples of these
two Ophiurids ; O. panamensis exhibits a very great variety of colour
pattern, due probably to the wide range of the species; the darker
varieties are found in the more northern parts of its area of distri-
bution.

Ceelenterata.

Pennatulida of Mergui Archipelago.t—Prof. A. Milnes Marshall
and Dr. G. H. Fowler report on the Pennatulids collected by Dr. J.
Anderson. Representatives of five genera and ten species, of the latter
of which two are new, were obtained. The numerous examples of both
Pteroeides Lacazii and P. chinense exhibit great variability, and in each
case these may be arranged in two groups; the same is true, also, of
P. espert. Virgularia Rumphii has colonies which may be as much as
900 mm. long; the swelling at the end of the stalk is shown to depend
on the state of contraction of the individual and is a character of no
practical value in classification. Fifteen specimens of this genus are
referred to a new species which is called V. prolifera ; all show the
truncation of the upper end of the rachis that is so characteristic a
feature of the genus. The other new species in the collection— Policella
tenuis—was represented by a single example 252 mm. in length ; it can
easily be distinguished from P. mawillaris which was collected with it.

Lebrunia neglecta.S—Prof. J. P. M‘Murrick has a note on this
incompletely known Actiniarian. Its original describers, Duchassaing
and Michelotti, were wrong in saying that it has five dichotomously
branched processes, for it has six; these are, to use the recent nomencla-
ture of R. Hertwig, pseudotentacles. Allied to this form are, apparently,
the deep-sea Actinie, Ophiodiscus annulatus and O. sulcatus, described
by Hertwig from the ‘Challenger’ collections, but they are not con-
generic. This is proved by the absence in Lebrunia of a circular muscle
and of specialized gonophoric mesenteries. It belongs to Hertwig’s
tribe Hexactiniz, the three divisions of which formed by Andres appear
to be natural; to these the author proposes to add a fourth which he
calls Dendromeline. It would include Lebrunia and probably Ophio-
discus, and may be characterized by the presence of marginal tentacles
arranged in cycles, and by the pessession of pseudotentacles arising from
the column-wall. Further details are promised.

* Ann-and Mag. Nat. Hist., iii. (1889) pp. 422-3.

+ Proc. Acad. Nat. Sci. Philad., 1889, pp. 76-7.

{ Journ. Linn. Soc. Lond., xxi. (1889) pp. 267-86 (2 pls.).
§ Zool. Anzeig., xii. (1859) pp. 38-40.

530 SUMMARY OF CURRENT RESEARCHES RELATING TO

Remarkable Actinian.*—Dr. C. P. Sluiter corrects an error which
he committed in an article on two remarkable Gephyrea in vol. xlviii.
(p. 233) of the Nat. Tijdschr. voor Nederl. Indié. He now sees that
Diphthera octoplax is an Actinian. He urges that he had never before
seen an Actinian of the kind, and that no one who saw it alive would
hesitate to call it one of the Phascolosomata. ‘The anterior end of the
body looks like a proboscis and acts energetically and not slowly. The
histological characters of the integument are much like those of a Sipun-
culid. The creature should, apparently, be placed in the genus Hdwardsia.

Caryophyllia rugosa.t—Herr G. v. Koch has made an examination
of the structure of Caryophyllia rugosa. This form has especial interest
from the fact that it was described by Moseley as having the septa
arranged in octameral fashion. With this Herr v. Koch cannot agree,
as he finds that there are at first six septa of the first order, which are
followed by six of the second. Both of these sets are arranged quite
symmetrically. When the septa of the third order appear there is some
irregularity, for those in two adjoining sections appear earlier than those
in the rest, while, at the same time, the interjacent septa of the second
order grow more rapidly than their homologues in the four other sectors.
There are thus gradually developed eight larger septa (six of the first
and two of the second order), and eight smaller septa (four of the second
and four of the third order), so that the coral comes to look as though it
were octamerous. When the third cycle is complete, the number of |
septa is again of the hexameral type, but soon afterwards eight septa of
the fourth order appear in the already mentioned two sectors. The
whole number is thus raised to thirty-two, and as this is not increased
the octameral type again becomes apparent. We have here, therefore, -
an interesting example of a coral which, when adult, is regularly
octamerous, being in its youth six-rayed.

Semzostomatous and Rhizostomatous Meduse.{—Dr. E. Vanhéffen
describes the Medusze of these orders collected on the ‘ Vettor Pisani’
expedition. Of Semzostomata, six new species are described— Pelagia
neglecta, P. crassa, P. minuta, Chrysaora chinensis, Desmonema chierchiana,
and Aurelia dubia ; seven others are revised ; and a systematic review is
taken of all the known species in the above genera. Of Rhizostomata,
six new forms were discovered— Cassiopeia picta n. sp., Loborhiza orna-
iella g. et sp. n., Stomolophus chunii nu. sp., Rhizostoma hispidum ux. sp.,
Mastigias orsini n. sp., and Desmostoma gracile g.etsp.u. After deserib-
ing these forms, the author takes a systematic survey of known Rhizo-
stomata. The third part of his memoir is devoted to a survey of the
geographical distribution with which a map is given. The two orders
differ greatly in their range. Thus in the Red Sea, Semzostomata are
absent, but Rhizostomata are abundant; on the Pacific coast of North
America the reverse is true. From similar facts Dr. Vanhéffen con-
cludes that the Rhizostomata usually prefer warmer waters, while the
Semzostomata are more abundantly represented in temperate zones.

Siphonophora of Canary Islands.§—Prof. C. Chun reports that he
has discovered a considerable number of new species of Siphonophora off

* Zool. Anzeig., xii. (1889) pp. 47-8. + Morphol. Jahrb., xv. (1889) pp. 10-20.

{ Bibliotheca Zool. (Leuckart and Chun), Heft 3 (1889) 52 pp., 6 pls. and map.

§ SB. K. Akad. Wiss. Berlin, 1888, pp. 1141-73. Ann. and Mag. Nat. Hist., iii.
(1889) pp. 214-46,

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 581

the Canary Islands. Some of them are interesting because of their
peculiarities of structure, and others because they are forms which
unite groups which hitherto appeared to be isolated. Before com-
mencing the detailed account of the species which he observed, Prof.
Chun makes some remarks on the recently published views of Prof.
Haeckel.

With regard to the proposed division of the Siphonophora into two
subclasses, Prof. Chun urges that Haeckel has founded his speculations
on two larval forms of very different morphological value. The Velel-
lidas certainly represent not only the most complicated in structure, but
also the most divergent of the Physophoride; but there is no feature
in their organization which cannot be explained by gradual adaptation
to an existence at the surface of the sea. The author would propose to
divide the order Physophoride into two suborders, one of which would
include all with an unchambered pneumatophore functioning as a gas-
gland (Haplophyse), while in the other there would be the (partially) air-
breathing Velellide (Trachophyse) with a chambered pneumatophore,
stigmata, and trachee. Prof. Chun also urges reasons against Haeckel’s
Medusa-theory of the morphology of the Siphonophora.

Among the new forms described are Doramasia g. n. for Ersea
Bojani Esch., and D. picta sp. n.; in it the nectocalyx is diphyidiform,
slender, with a long apex to the subumbrella drawn out in the form of a
tube, and the Eudoxiz have special nectocalyces; in Halopyramis g. n.
the nectocalyx forms a broad, four-sided, tetragonal pyramid, the
hydreecium is infundibuliform, with a projecting denticulate margin, the
oil-receptacle is very large and situated in the axis of the pyramid, the
subumbrella is excentric, the stem is abbreviated and not protrusible,
while the Eudoxiz have no special nectocalyx, and become free as in
Cuboides.

The family Amphicaryonide is formed for Amphicaryon g. n.; in it
the nectocalyces have a rounded exumbrella, and the stem is metamor-
phosed into a disc ; the bud-groups are set free as diplophysiform Eudoxiz.
The Stephanophyide contain the new genus Stephanophyes, and are defined
as Calycophoride with four nectocalyces placed like a wreath in the
same plane, and with heteromorphous tentacles. In the internodes of
S. superba sp. n., the heteromorphous tentacles which have been as yet
found only in Stephanophyes among the Calycophoride, are found placed.
This species is, of all the Siphonophora known to the author, the
most delicate, and one of the most magnificent. It is perfectly trans-
parent, and may be as much as 18 inches long. “The graceful play of
its heteromorphous tentacles, the energetic pumping movements of the
large calyces and the numerous special nectocalyces, the bright red
colouring of the knobbed fluid vessels with their shining oil-drops, the
delicate rosy or emerald-green shimmer of the gastric polyps, the perfect
transparency of the large globular ova, and the delicate flesh-tint of the
male manubria all combine to mark Stephanophyes as one of the most
splendid objects among pelagic animals.” This interesting form passes
through a remarkable metamorphosis. The youngest specimens, which
are perfectly transparent, and therefore easily escape even the practised
eye, display the characters of the genus Lilyopsis ; they possess two
nectocalyces with the fluid-canal only once divided dichotomously, and
are completely devoid of the heteromorphous tentacles found in the
internodes of older groups. This new genus unites the Prayide and

532 SUMMARY OF CURRENT RESEARCHES RELATING TO

Polyphyide, and has some points of structural resemblance to the
Physophoride.

Passing from the Calycophoride to the Physophoride, the author
points out the many resemblances which connect the two orders. In
the embryos of both a heteromorphous rudimentary nectocalyx is formed,
which is lost in most if not all Calycophoride, while in the Physo-
phoride it becomes converted into the pneumatophore. In the more
highly organized Calycophoridee there are a number of calyces of the
same form, the close concentration of the buds into Eudoxia-groups is
given up, aud in some species the stem is transformed, as in many
Physophoride, into a gemmiparous disc. Here, then, we have a series of
characters which seem.to indicate that the Physophoride took their
origin, if not from the Stephanophyide or Polyphyide, at least from a
root common to the two orders. Stephanophyes with its heteromorphous
tentacles shadows forth a condition which has hitherto been regarded as
an exclusive characteristic of the Physophoride.

The morphology of Halistemma pictum has been closely examined,
and it is shown that the order of gemmation is reguiar; the author
leaves it to Prof. Haeckel to reconcile this fact with his theory of the
multiplication and dislocation of the medusa-organ on the Siphonophoran
stock. In the post-embryonic development of Crystallodes rigidum a
point of great interest is the peculiar formation of the larval tentacles.
Haeckel thinks that the cnidaria of the primary tentacle are directly
developed into the definitive cnidaria. Observation, however, has shown
that they are larval structures, which, later on, are succeeded by hetero-
morphous organs. The nectostyles of some gigantic examples of
Forskalia ophiura were a foot in length.

New Athorybia.*—Mr. J. Walter Fewkes describes Athorybia cali-
fornica sp. u., which differs from any known species in the form of its
tentacular knobs. 'The sacculus, which ordinarily forms a bell-shaped
covering, is much modified and reduced in size; it is a globular or
hemispherical enlargement which shows the spongy cellular walls which
have been described in the knobs of the genus Rhizophysa. If the
question were raised as to whether this new form was not the young of
some long-stemmed Physophore, like Agalma, the author confesses that
it may be so. But if larval, this new form is different from any larva
yet described. The sexual bodies are but little developed, and, even if
they were well so, that fact alone would not prove the maturity of the
animal, for among the Physophores there are known genera in which the
sexual products are matured before the adult form is reached.

Eyes of Acalephe.t—Herr W. Schewiakoff has examined the eyes
of several Acalephe. He finds that there is great diversity of structure,
and that they are so far genetically connected that the simpler only
represent developmental stages of such as are more highly organized.
In the simplest cases the eyes have the form of a pigment-spot, as in
Aurelia aurita. These spots are formed of cells, the pigment- and
the optic-cells, with two different functions, which are performed in
definite areas of the ectoderm, the so-called sensory epithelium. These
are the districts from which the light-perceiving spots are developed.

The next step in the further complication of the optic organ consists

* Ann, and Mag. Nat. Hist., iii. (1889) pp. 207-10 (1 pl.).
+ Morphol. Jahrb., xv. (1889) pp. 21-60 (3 pls.)

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 5338

in the sensory epithelium, which is differentiated for the perception of
light, sinking into the body and so giving rise to the so-called optic pits ;
such organs may be found in Charybdea marsupialis, and in their com-
position they differ not at all from the superficial pigment-eyes. Their
depression is not only a sign of the more definite localization of the per-
cipient spots, but a protective arrangement. Still deeper depression leads
to the so-called goblet-eyes, which are first met with in the proximal
goblet-eyes of Charybdea ; in conjunction with this depression there is
the development of a new constituent of the eye—the so-called vitreous
body which is differentiated off from the pigment-cells ; it closes the
eye cup externally and fills its cavity. A further, though less con-
siderable, complication is found in the distal goblet-eyes of Charybdea,
where the invagination of the sensory epithelium forms a secondary
outgrowth. In connection with this we meet with a differentiation of
the cellular elements which form the wall of the eye; the cells abutting
on the proximal wall-of the optic cup are formed of pigment-cells, and
this arrangement is functionally that of an iris, for by it the lateral rays
of light are cut off.

The goblet-eyes of Aurelia are developed on quite a different type.
They are not formed, like the other eyes of jelly-fishes, by the invagina-
tion of the sensory epithelium, but of the endoderm and, possibly, of the
supporting lamella; the goblet-wall is, consequently, formed of altered
endodermal cells which are filled with pigment. This invagination of
the endoderm is followed by that of the optic cells of the ectoderm. As
a result of this interesting mode of origin it follows that the nerve-fibres
do not arise from inside but from outside the optic cells, and are con-
nected with their outer ends; the free ends appear, therefore, to be
turned away from the light, which must pass through the whole of the
nerve-layers before it reaches the ends of the optic cells. This relation
of parts is not unlike that which obtains in the eyes of Onchidia, Lamel-
libranchs, Arachnids, and Vertebrates.

The causes, however, are quite different, and the goblet-eyes of
Aurelia must therefore be regarded as belonging to a special type which
cannot be directly compared with any yet known type of eye; there is,
indeed, a certain resemblance to the eyes of the Turbellaria.

The structure of the lens-eyes of Charybdea, which attain a very
high grade of development, is very interesting. They are derived from
goblet-eyes, the goblet narrowing at its outer end and becoming con-
stricted off from the body-epithelium. The orifice becomes closed, and
an optic vesicle completely shut off from the exterior becomes developed ;
this is surrounded by the afferent nervous layer as far as its superficial
part. In addition to this the body-epithelium grows together at the
point where the invagination has taken place, and forms a thin trans-
parent layer—the so-called cornea. Simultaneously with this there is a
differentiation of the cells which form the outwardly directed wall of
the primitive optic vesicle. These increase greatly in length, and, later
on, form the spherical lens which projects into the optic vesicle, and
occupies a large part of it. The cells of the vesicle at the periphery of
the lens become differentiated into the so-called iris. The proximal
lens-eye no doubt arises in the same way as the distal, but the proximally
directed and not the outer wall of the vesicle becomes differentiated
into the lens; a gelatinous stalk is formed which carries the lens.

This mode of origin and the peculiarities of these eyes of Charybdea,

534 SUMMARY OF CURRENT RESEARCHES RELATING TO

cannot be compared with any known type of eye. In some, the
structureless lens is developed within the optic vesicle, and is a secre-
tion-product of the cells which compose it; such eyes are to be found in
Gastropods, Cephalopods, Annelids, and in Peripatus. In others the
lens is developed outside the primary optic vesicle, and is either
structureless as in many Arthropods, or composed of cells, as in the
dorsal eyes of Onchidium, and the eyes of Lamellibranchs, and Verte-
brates. The vestigial parietal eye of some Reptiles appears to have the
same type of lens as the eyes of Charybdea, for it is formed from the
outer wall of the optic vesicle. There appear, then, to be three types of
lens-eyes.

Porifera.

Cliona.*—Dr. J. Leidy gives a short and interesting account of this
boring sponge, and describes a new form from the coast of Florida,
which he proposes to call C. phallica ; it has an opening at its summit
which is closed when the sponge is disturbed.

Protozoa.

Functional Differentiations in Unicellular Beings.;—M. Fabre-
Domergue replies to some criticisms of M. Maupas as to the existence of
functional differentiations in unicellular organisms. Taking Didinium
nasutum, he urges that at the moment when prey is ingested, there is a
clear axial tract, resulting from the formation of a canal which extends
from the mouth to the anus ; the existence of this canal is confirmed by
the retraction of its wall under the influence of iodine, and by the course
taken by the food which always goes straight from mouth to anus. M.
Maupas denies the existence of this canal because it has no proper
walls, but he likewise, it is true, denies that an air-bubble has walls.
Functional differentiation is still better marked in the excretory system ;
the most striking example is the remarkable contractile plexus of Cyrto-
stomum, but it is only the most perfect expression of a structure which
exists in all Ciliata, and traces of which may be found in a large number
of forms.

Maupas’ Researches on Ciliata.{-—Prof. A. Gruber does not accept
all the general conclusions which Maupas has drawn from his re-
searches on ciliated Infusorians. (1) The multiplication has been
shown to occur in asexual cycles, which end in degeneration and death
if conjugation does not take place. Therefore, Maupas maintains, the
doctrine of the immortality of the Protozoa must be abandoned. But
the conjugation always occurs in the natural conditions of life, so that
Maupas’ objection is not after all serious. It is only necessary to add
to Weismann’s original statement a saving clause as to the necessity of
conjugation. (2) Maupas opposes Weismann in regard to the equality _
of the products of division. After 50-100 divisions the products are
both morphologically and physiologically different. But the species
still persists, and Weismann does not deny such variability, nor even the
inheritance of acquired characters in the Protozoa. (8) Maupas insists
that Weismann should have experimented before he theorized, but

* Proc. Acad. Nat. Sci, Philad., 1889, pp. 70-5.
+ Ann. de Microgr., ii. (1889) pp. 168-72.
+ Biol. Centralbl., ix. (1889) pp. 14-23.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 539

Gruber points out that even Maupas’ researches owe their impulse to
the precedence of hypotheses.

Gruber notes two cases, one observed by Jickeli, the other by him-
self, where the micronucleus of a Paramzxcium appeared to be absent,
but where the symptoms of senile degeneration were not exhibited.
According to Gruber the macronucleus consists of “ histogenetic”
plasma, the micronucleus of germ-plasma.

Finally, Gruber refers to his recent experiments on Actinophrys sol.
The marine form, with few vacuoles, soon acquires them in fresh water,
which soaks in much more abundantly. The reverse experiment was
also made. The marine Ameba crystalligera also became richly vacuo-
lated in fresh water. None of the environmental variations, however,
were more than transitory, that is to say, they disappeared when the
original conditions were restored.

Two New Infusorians.*— M. Fabre-Domergue describes a new
species of Colpoda, which he calls C. Henneguyi, which was found in an
old maceration of leaves and dried detritus collected in the garden of
the Collége de France. Its slow movements and its large size would
make it comparatively easy to study, were its protoplasm not obscured
by fine and numerous granulations. It differs in furm from C. cucullus,
and normal individuals vary from 0°31 to 0°65 mm. in length. After
describing the details of its appearance, the author states that it gives
rise to division-cysts and to lasting cysts; the former have a very
delicate membrane, and the contents divide into four. The lasting
cysts are smaller and more rounded, and have a thick and resisting
envelope.

Pronoctiluca pelagica is the name given to a new genus of flagellate
Infusoria found on the surface of the sea at Concarneau. In the form
of its mouth, and the presence of two flagella, it approaches Chilomonas,
but, on the other hand, its tentacle is exactly like that of a Noctiluca
minus the striation. The author believes that we have here a form
which is intermediate between the Flagellata and the Cystvflagellata.

Anoplophrya aeolosomatis.;,—Mr. H. H. Anderson gives a descrip-
tion of a new ciliate infusorian parasitic in the alimentary canal of
Aeolosoma chlorostictum (Wood-Mason, MSS.). It differs from all
members of its genus except A. mytili in possessing a single contrac-
tile vesicle, and from it it may be distinguished by the shape and form
of its endoplast, which is axial, band-shaped, extending nearly the whole
length of the body, in most specimens straight, though in a few some-
what curved or 8-shaped; this endoplast is coarsely granulated, and in
one specimen, five large and highly refractive, though not crystalline,
particles of different sizes were seen in it. The surface of the infusorian
is densely ciliated, and finely striated in a longitudinal direction. The
contractile vacuole is situated centrally above the endoplast. An inter-
esting process of multiplication by transverse fission, was observed to
resemble that which takes place in A. nodulata. It was noticed that
the individuals in process of division were far larger than those that
were not being divided, and that the segments were very much smaller
than the parent one.

* Ann. de Microgr., ii. (1889) pp. 353-7 (1 pl.).
+ Journ. Asiat, Soc. Bengal, lvii. (1889) pp. 381-3 (1 pl.).

536 SUMMARY OF CURRENT RESEARCHES RELATING TO

Formation of Spores of Gregarine of Earthworm.*—Dr. F.
Henneguy has applied the section-method to the study of Gregarines.
The two chief difficulties met with are the small size of these creatures,
and the resistance offered by their investment to the penetration of
fixing liquids; these are best met by hardening the organisms in the
organs which containthem. Observations have been made on Clepsidrina
blattarum, Klossia helicina, and Monocystis agilis ; but the last alone has
as yet given good results.

If a series of sections of the so-called testicles of the earthworm are
made in May and June, almost all stages in the development of the
parasite may be observed. The young consist of a small mass of homo-
geneous protoplasm, which is surrounded by a delicate membrane, and
contains a nucleus of some size, which is provided with a nucleolus
which stains deeply with carmine. In the adult the protoplasm is filled
with refractive bodies; these, when examined under a high power, are
seen to be rounded or ellipsoidal in form, and they may or may not be
of the same size. The author agrees with Maupas in regarding these
bodies as being amylaceous. From the characters which they present
with polarized light, it would seem that their axial portion consists of a
substance which is more condensed than the rest.

The general results of previous observers on the development of
Monocystis are confirmed, and some new facts have been discovered as to
the part played by the nucleus. When a Gregarine is about to undergo
encystation the nucleus has a large nucleolus, and the surrounding
protoplasm is devoid of refractive bodies. Vacuoles soon appear in the
nucleolus, and this breaks up into several small grains of chromatin
which are connected by an achromatic plexus. The nucleus then under-
goes indirect division, and what appears to be an accessory nucleus is
developed. If the contents of the cyst do not divide, the nuclei continue
to multiply by karyokinesis and emigrate to the surface, where each ~
nucleus is soon surrounded by a small quantity of protoplasm. At the
moment when the peripheral layer of the cyst becomes organized into
cells one does not see around each nucleus the radiating lines which are.
observed in the parablast of mesoblastic eggs when the nuclei become
the centres of cell-formation. It is very probable that the small size of
the cells of the cysts of Monocystis alone prevent us from seeing those
radiate lines which appear to play an important part in the formation of
the cellular plate. Hach small superficial cell of the cyst soon becomes
surrounded by a resistant envelope, and becomes a spore or pseudo-
navicella.

Some of the nuclei remain at the centre of the cyst and, later on,
undergo degeneration; the process of their disappearance recalls that
which Flemming has noticed in the cells of the ovarian follicles of the
rabbit. When the contents of the cyst divide into a small number of
large masses the process of the formation of the spores is identical, and
each of these masses behaves like the undivided cyst. The method of
sporulation described by Lieberkiihn, in which the whole contents of
the cyst divide into spores, has not been observed by the author, Micro-
spores are formed in much the same way as macrospores. It is possible
that microspores and macrospores are not formed by one and the same
species. Both kinds contain a nucleus of some size, which is provided

* Ann, de Microgr., i, (1888) pp. 97-107 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. ai

with a chromatic plexus; this nucleus divides by karyokinesis; each of
the daughter-nuclei passes to one of the ends of the spore, where it
undergoes two successive divisions, in such a way that the spore contains
two groups of four small nuclei. These pass to the middle of the spore,
the protoplasm of which becomes divided into eight falciform nucleated
bodies, surrounding the “noyau de reliquat” of Schneider. This
nucleus does not take up staining reagents, and the term applied to it
is inexact, for it does not exhibit any of the characteristic reactions of a
nucleus; it is formed of a mass which is more finely granular and more
refractive than the rest of the protoplasm of the spore. It is placed at
the centre, and round it the falciform bodies are organized ; it seems to
diminish in size during the development of the spore and to serve for
the nutrition of the falciform bodies. The author proposes to speak of
it as the central globule.

Cystodiscus immersus—a Myxosporidium found in the gall-
bladder of Brazilian Batrachia.*—-Dr. A. Lutz has found in the gall-
bladder of certain frogs and toads a parasite which would seem to have
no pathological significance. Macroscopically it appears as a thin round
transparent disc, sometimes surrounded by a whitish periphery.

Thirty to fifty individuals may be found in one gall-bladder, and in
size they sometimes attain to a diameter of 14-2 mm., with a thickness
equal to 1/20-1/10 of their diameter. Under the Microscope these discs
are seen to be incased in a transparent structureless membrane, which is
very resistant to reagents. ‘The organism has no power of spontaneous
movement. ‘The contents of the discs are numerous vesicles, which by
close apposition become polygonal. They are not nucleated, and if they
are set free they speedily vanish, as does their delicate investing sheath.

The most prominent characteristic of the parasites is the spores, which
lie outside the vesicles, and usually in pairs. These spores are of various
sizes, and when ripe attain a length of 12-14 p, and width of 9-10 p,
being oval in shape, with blunt ends. They are made up of two flaps or
valves and two almost spherical polar corpuscles. They contain an ex-
tensile filament, which exceeds the whole length of the spore four or five
times. When indrawn it is spirally rolled up and scarcely visible. By
means of caustic potash it can be extruded. The rest of the spore is
occupied by a transparent plasma-mass, coagulable by reagents.

With regard to the development of the spores, the author first
observed them as oval bodies containing two pale small polar corpuscles,
the rest of the body being dark. The latter decreases in size and clears
up, the investing membrane pari passu appearing, and the polar bodies
becoming larger. No nucleus was observed.

* Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) pp. 84-8.

538 SUMMARY OF CURRENT RESEARCHES RELATING TO

BOTANY.

A. GENERAL, including the Anatomy and Physiology
of the Phanerogamia. |

a. Anatomy.*
(1) Cell-structure and Protoplasm.

Growth of the Cell-wall.j—Herr HE. Strasburger continues his in-
vestigations on the growth and structure of the cell-wall, especially in
relation to Wiesner’s discovery { of the constant presence of albuminous
substances in the cell-wall. Many phenomena connected with the growth
of the cell-wall hitherto inexplicable he now explains on the theory of
the entrance into it of the living protoplasm, the cytoplasm or hyaloplasm
of the cell. In the same way cutinized, suberized, and lignified cell-
walls owe their characters to the entrance of foreign substances from
without.

The development was especially examined of the spores of the
Hydropteridee (Rhizocarpex). In Azolla the massule are first formed
when the formation of the membrane of the microspores is completed.
Round the microspores are formed clear borders, consisting of a fluid
derived from the surrounding protoplasm; these borders unite with one
another so that finally a number of hyaline vesicles are contained within
the microsporange, separated from and surrounded by the hyaloplasm.
From these vesicles the massule are formed, which are therefore derived
from the hyaloplasm which has entered the vesicles. When mature the
massule resemble in structure cutinized cell-walls. The same substance
from which massule and glochids are formed in the microsporanges gives
rise in the megasporanges to the peculiar floating apparatus. The
perinium on the megaspore of Salvinia is a structure of the same origin.

In the formation of the pollen-grains of the Onagraries a similar
- process takes place; and in those pollen-grains which are provided with
spines or other prominences projecting outwards, these are formed out
of a living substance which enters the extine from the hyaloplasm.
Similar observations were made on the development of the elaters of
Equisetum, on the spore-membranes of Riccia and Sphzrocarpus, on the
oogones of Peronospora, &e.

In epidermal cells it was proved in a number of instances that the
cuticle-layer originates as a lamella of cellulose, and that it is only later
that the substance which brings about the cuticularizing enters the
cell-wall; this substance is not cutin, but is a living constituent of the
body of the cell. In the processes of suberization and lignification the
nature of the changes is not so clear; but all striation and stratification
are probably the result of the introduction into the constitution of the
cell-wall of a foreign substance derived from the hyaloplasm.

Structure of the Cell-wall.§—According to M. L. Mangin, the first
division-wall formed in cell-division consists of pectose, on both sides
of which layers of cellulose are then formed, while it increases itself in

* This subdivision contains (1) Cell-structure and Protoplasm; (2) Other Cell-
contents (including Secretions); (3) Structure of Tissues; and (4) Structure of
Organs.

“+ ‘Ueb. d. Wachsthum vegetab. Zellhaute, Svo, Jena, 1889, 186 pp. and 4 pls.
See Bot. Centralbl., xxxvii. (1889) p. 394.

t Cf. this Journal], 1886, p. 818. § Comptes Rendus, cvyii. (1888) pp. 144-6.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 539

thickness and becomes the middle lamella of the wall. In many cases
pectose is also a constituent of the thickening-layers, so that the form
of the cell-wall is retained after destruction of the cellulose; less often
the thickenings consist of pure cellulose. The walls of the tapetal cells
in young anthers and those of young pollen-cells are composed, according
to the author, entirely of pectose. Conversion into mucilage and cuticle
are results of the transformation of pectose, not of cellulose.

Permeability of Protoplasm for Urea.*—Herr H. de Vries states
that the protoplasm of mature cells can take up urea, Comparing the
rapidity of diffusion of urea with that of glycerin, he finds an illustration
of the general law that the diffusibility of a substance is in inverse pro-
portion to its molecular weight; that of glycerin C,H,O, (= 92) being
considerably less than that of urea CON.H, (= 60). The isotonic
coefficient of urea he places at 1°70.

Diosmose through the Cellulose-pellicle of Phragmites communis.{
—According to Herren Kruticky and Bielkowsky, the cellulose-pellicle
of this grass has a greater endosmotic equivalent than that of any
artificial membranes hitherto used for the purpose. In the manometer
the endosmotic force withstands a pressure of nearly one atmosphere.
The limit of elasticity amounts, on the average, to above 500 er.

Reduction of Silver in the living-cell.t—Prof. W. Pfeffer strongly
contests the assertion of Loew and Bokorny,§ that the reduction of
silver from a slightly alkaline solution is a conclusive proof of the
presence of “active albumin,’ and consequently of the cell being in
a living condition, which he asserts to rest on pure hypothesis. With
the death of the cell and its immediate result—the mixing of substances
previously separated, and the exosmotic separation of substances pre-
viously in contact—changes of various kinds are effected, of the chemical
nature of which we at present know very little.

Messrs. Loew and Bokorny reply || to Dr. Pfeffer’s objections, re-
ferring, in proof of the correctness of their conclusions, to the records
already published of their researches. In particular they assert that the
reduction of the silver-salt cannot be due to the presence of tannin, at
all events when this substance is not present in any large quantity.

(2) Other Cell-contents (including Secretions).

Chemistry of Chlorophyll.47—Dr. E. Schunck gives a short resumé of
the present state of our knowledge on the chemistry of chlorophyll, and
also adds a few new facts to the stock already accumulated.

In works on vegetable physiology the term chlorophyll is sometimes
applied to the complex of substances contained in living green cells,
which take part in the process of assimilation, and of which the colouring
matter constitutes a portion; and chemists, following the example of
physiologists in giving a name to the whole which should have been
confined to one part, have been led to ascribe to chlorophyll properties
which no mere chemical substance can possibly possess. The author

* Bot. Ztg., xlvii. (1889) pp. 309-15, 325-34. Cf. this Journal, 1888, p. 617.

+ Arbeit. St. Petersburg. Naturf. Gesell., xix. (1888) p. 3. See Bot. Centralbl.,
XXxviii. (1889) p. 486.

¢ Flora, Ixxii. (1889) pp. 46-54. § Cf. this Journal, 1881, p. 906.

|| Bot. Centralbl., xxxviii. (1889) pp. 581-4, 612-5.

4 Ann. of Bot., iii, (1889) pp. 65-121 (1 pl.). Cf. this Journal, 1887, p. 606.

540 SUMMARY OF CURRENT RESEARCHES RELATING TO

then, to avoid misconception when using the term chlorophyll, means
simply the substance, or it may be mixture of substances, to which the
pure green colour of ordinarily healthy leaves and other vegetable
organs is due. The various attempts to isolate chlorophyll are then
described. Berzelius, Mulder, Morot, and Frémy all employed pro-
cesses for preparing chlorophyll involving the use of hydrochloric
acid, and really obtained products resulting from its decomposition.
M. Gautier prepared chlorophyll with neutral solvents, and obtained a
substance in distinct crystals of an intense green colour; this product,
as well as Hoppe-Seyler’s chlorophyllan, are probably derivatives of
chlorophyll. The product obtained by Hansen, chlorophyll-green, is
however a sodium compound, and the author’s conclusion is that chloro-
phyll has not yet been obtained in such a state of purity as to allow of
its physical and chemical properties being described. Most observers
agree in stating that chlorophyll is insoluble in water and soluble in
ether, chloroform, carbon disulphide, ethereal and fatty oils, and similar
substances. ‘That iron in some form or other is an essential constituent
of chlorophyll, has been repeatedly asserted and as often denied ; the
author is of the opinion that it is not.

The absorption-spectrum of chlorophyll presents several points of
controversy, especially the broad indistinct bands at the blue end of the
ordinary chlorophyll-spectrum, which are only seen by sunlight, and are
distinguished as bands V. and VI. (German notation). Some observers
consider these as true chlorophyll-bands, while others are of opinion that
they belong to a yellow colouring matter accompanying chlorophyll
called xanthophyll. The author takes this latter view, seeing that it is
possible to isolate a colouring matter from leaves in regular lustrous
crystals, which gives yellow solutions showing two distinct bands in
the blue when sufficiently dilute, but no bands whatever in the red,
yellow, or green, however concentrated they may be.

Dr. Schunck then describes the products formed in the processes of
decomposition to which chlorophyll has been hitherto submitted. By
the combined action of ether and hydrochloric acid, Frémy obtained two
colouring matters, a blue and a yellow; these he named phyllocyanin
and phylloxanthin. Phyllocyanin is one of the most important deriva-
tives of chlorophyll, its properties being very interesting. When dry
it has the appearance of a dark-blue mass, which, when examined under
the Microscope, is found to consist almost entirely of elongated rhom-
boidal or irregularly six-sided crystalline plates, which are generally
opaque, but, when very thin, are translucent, and then appear olive-
coloured by transmitted light. Phylloxanthin is the product obtained
by dissolving the precipitate formed by acids in an alcoholic extract of
leaves in ether, and adding concentrated hydrochloric acid to remove the
phyllocyanin, where it remains dissolved in the upper ethereal liquid.
Solutions of phylloxanthin have a yellowish-green colour, with a pro-
nounced reddish tinge, and may be thereby distinguished from solutions
of phyllocyanin, which are more decidedly green. They show a spec-
trum of four bands only, that of phyllocyanin having five ; an admixture
of the latter viith phylloxanthin may therefore be easily detected.

Dr. Schunck then describes the various compounds of phyllocyanin,
and also the action of alkalies on chlorophyll, which has been less fre-
quently studied than that of acids, partly perhaps because alkalies do not
produce such marked changes as acids. One of the most interesting

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. — 541

substances obtained by the action of alkalies is phyllotaonin, thus called
by the author from its resemblance in colour and lustre to the eyes in a
peacock’s tail. The action of anilin on chlorophyll is then described,
and the properties of a substance termed anilophyll are enumerated.

The author concludes by discussing the chemical constitution and
functions of chlorophyll. It may be assumed that chlorophyll is a kind
of lecithin, of which phyllocyanin forms as it were the nucleus, together
with an unknown acid and an unknown base; and he brings forward the
hypothesis that the unknown acid may be carbonic acid. The presence
of a body having a chemical constitution such as that would, it is evident,
serve a useful purpose in the vegetable economy. Some remarks are
also made on the substances which accompany chlorophyll, and on the
chlorophyll of animals.

Formation of Chlorophyll by Conifere in the dark.* — Herr H.
Molisch states that Gingko biloba (Salisburia adiantifolia) furnishes an
exception to the general rule that seedlings of conifers have the power
of forming chlorophyll even when completely excluded from light. Not
a trace could be detected in a considerable number of observations.

Formation of Starch in the Leaves of Sedum spectabile.t—Prof. J.
Bohm adduces further evidence of his view of the incorrectness of the
assumption that, because starch is again rapidly formed in leaves from
which it has been removed by subjecting them to darkness, when again
exposed to the light in air containing carbon dioxide, that therefore the
starch then found in the chlorophyll-grains is a direct product of assimi-
lation. His experiments were made on the coriaceous leaves of Sedum
spectabile, and confirm his previous conclusion that when the starch has
been removed a large quantity of sugar still remains in the leaves, which,
on fresh exposure to light, is converted into starch.

Mode of occurrence of Tannin in Plants.t—According to Herr H.
Moeller, tannin occurs in plants in two different forms :—(1) As an iron-
green solution in the cell-sap, commonly permeating the cell-wall, as
also the nucleus and chlorophyll-grains. With potassium bichromate
this tannin is precipitated in the form of an irregular amorphous
powder. (2) Much the most common form is that of a homogeneous
strongly refringent oily fluid, usually coloured blue by iron-salts. This
form ean be especially well detected in leaves of Pelargonium by
Gardiner’s reagent (ammonium molybdate). An examination was made
of leaves of a number of different plants, and the author concludes
from the concurrent presence of tannin and starch in the assimilating
cells, and the separate occurrence of each in the conducting tissue,
and especially from the large accumulation of tannin in spongy paren-
chyme, parenchyme-sheaths, and the conducting parenchyme of vascular
bundles, that the transference of the carbohydrates in the form of com-
pounds of tannin is highly probable.

(3) Structure of Tissues.

Assimilating Tissue and Periderm in leafless plants.§—Sig. H.
Ross has examined the structure and development of the assimilating

* Oesterr. Bot. Zeitschr., xxxix. (1889) pp. 98-9.

+ Bot. Centralbl., xxxvii. (1889) pp. 193-201, 225-32.

t Ber. Deutsch. Bot. Gesell., vi. (1888) General-Vers.-Heft, pp. Ixvi.-Ixxxii.
§ Nuov. Giorn. Bot. Ital., xxi. (1889) pp. 215-45 (1 pl.).

1889. 2 P

D442 SUMMARY OF CURRENT RESEARCHES RELATING TO

tissue or chlorenchyme, and of the periderm, in the branches of plants
with few or no leaves. Such plants generally manifest a tendency to
preserve for a long time unchanged the cortex and the epiderm, in order
to render possible a sufficient assimilation ; the increase in thickness is
at first inconsiderable; and hence the formation of periderm is retarded.
In some cases the periderm covers only a part of the branch; in others
it grows in the form of spots or longitudinal lines scattered irregularly
over the surface, which, after a certain time, unite to form a continuous
periderm round the whole of the branch. When increase in thickness
commences, the necessary space for the new tissues is obtained by the
rounding of the branches which were at first flattened, or by the
enlargement of sinuosities, so that the assimilating tissue may be pre-
served for the longest possible time. In other cases the periderm is
developed among the groups of assimilating tissue in the form of regular
longitudinal strips, which broaden in proportion to the increase in
thickness of the branch. This assimilating tissue may or may not
undergo subsequent changes. In Genista, where the groups of stereids
extend almost without interruption from the epiderm to the leptome,
through the whole breadth of the outer cortex, the periderm is formed
in the middle of the strips of assimilating tissue, that is to say, at the
bottom of the original sinuosities, preserving for a long time at its two
sides remains of the chlorenchyme.

Closing of the Bordered Pits in Conifere.*—Herr K. Pappenheim
proposes for solution the question whether the bordered pits in the
alburnum of the wood of Conifer are capable of being closed, and if
so, by what forces this is brought about. ‘Taking the silver fir as an
example, he describes a mechanical apparatus by means of which he
claims to have proved that this can take place in the alburnum of the
spring and summer; and he believes this fact to be of importance in
constructing a theoretical explanation of the course of the ascent of sap.

Structure of Lecythidacee.t—M. M. O. Lignier finds in the course
and arrangement of the vascular bundles a constant difference between
the Lecythidacese (Lecythidee, Barringtonies, and Napoleonez), and
the typical Myrtacez. In the former the anterior and posterior bundles
of the leaf-stalk are branches from the margins of the main cauline
bundles; the cortical bundles of the stem are normal leaf-trace-bundles.

(4) Structure of Organs.

Anatomy and Chemistry of Petals.t{—Dr. EH. Dennert describes the
structure and the colour of petals in a large number of plants. The
following are the more general results arrived at.

As compared with foliage-leaves, petals show usually much less
development of tissue, and the veins are of simpler structure and less
branched. ‘The number of stomates is usually comparatively small; in
some instances, as the perianth-leaves of Ornithogalum umbellatum, they
occur on both sides; in this plant long erystal-cells filled with raphides
occur between the epidermal cells. The cells of the epiderm of petals
do not generally exhibit any differentiation in the development of their

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 2-19 (1 pl.).

+ Ass. Frane. pour ’Avancem. des sci., 1887, 9 pp. See Bot. Centralbl., xxxvii.
(1889) p. 145.

{ Bot, Centralbl., xxxviii. (1889) pp. 425--31, 465-71 513-8, 545-53.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 543

cell-walls. Their usual form is that of papillae. As a rule yellow
petals have a stouter structure than those of other colours,

The colouring-matters of petals may be divided into two classes—
granular, and dissolved in the cell-sap; the former include, as a rule,
green, yellow, and orange, the latter red, blue, and violet petals. These
two kinds are sharply differentiated from one another, but are not un-
frequently mixed, as in the orange pigment of Colutea cruenta and
Fritillaria imperialis, and the brown of the wallflower. A yellow
pigment dissolved in the cell-sap is, however, not uncommon. The
granular substances, which may be called anthoxanthin, are a modifica-
tion of chlorophyll; the soluble pigments, known under the general
name of anthocyan, a modification of tannin. ‘These relationships are
proved by a number of experiments described in detail. The variation
in the colour of petals of the same or of allied species depends on the
extent of the metamorphosis of the tannin into the pigment, and on the
presence or absence of the yellow colouring-matter. The nature of
the chemical change in the transformation of the tannin is probably an
oxidation, and it is largely dependent on light.

As regards the distribution of the pigments ; the general rule, though
not without many exceptions, is that anthocyan occurs in the epiderm
and veins, the yellow pigment in the lower-lying tissue. Anthocyan
has clearly a close relationship to the erythrophyll of leaves.

Extrafloral Nectaries.*—Herr EH. Rathay asserts the existence of
extrafloral nectaries in a large number of species of Centaurea and in
other genera belonging to the Composite. The purpose of these organs
is not the same in all plants. They may exist for the purpose of diges-
tion, as in Nepenthes, or for the attraction of insects, such as ants, which
would otherwise injure the flowers, as in Impatiens tricornis, They were
found to contain a larger or smaller quantity of sugar in all cases except
the common peony. Although the insects most commonly found in
extra-floral nectaries are ants, yet in sunshine they appear almost always
to attract many others, Coleoptera, Hymenoptera, and Diptera; and the
term myrmecophilous plants sometimes applied to them is therefore
inexact. The sugar-producing parasitic Uredinex, to which the author
has already called attention,f appear to benefit the host-plant in the
same way as extra-floral nectaries.

Extrafloral Nectaries of Dioscorea.t—Herr E. C. Correns describes
these organs in about twelve species of Dioscorea, those of D. sativa and
Batatas having been especially studied. They are wanting in Testu-
dinaria elephantipes. ‘These depressed glands occur on the under side
of the leaf and in the cortical parenchyme of the stem and leaf-stalk.
They consist of a mass of cells rich in protoplasm and containing a
large nucleus, on the level of the hypodermal layer, their form being
ellipsoidal in the leaf, fusiform in the stem and leaf-stalk. ‘The secreting
surface, which has no epiderm in a physiological sense, is elliptical or
lanceolate, and is covered by a continuous cuticle. The peripheral layer
of cells is suberized in the mature nectary, and therefore represents a
protecting sheath. The leptome of the vascular bundles is connected
by transitional cells with the parenchyme-sheath which surrounds the

* SB. Zool.-Bot. Gesell. Wien, xxxix. (1889) pp. 14-21. Cf. this Journal, ante,
p. 87. + Cf, this Journal, 1883, p, 246.
{ SB. Akad. Wiss. Wien, xevii. (1889) pp. 651-74 (1 pl.).
2P 2

544 SUMMARY OF CURRENT RESEARCHES RELATING TO

nectaries of both stem and leaf. The nectary is formed at an early
period from a single epidermal cell, and the sheath from one or from a
very few cells lying directly beneath the mother-cell of the nectary. -

Elastic Stamens of Composite.*—Prof. T. Mcehan describes the
mode in which, in a large number of species of Composite, the column
of stamens matures its growth before the pistil becomes fully elongated ;
the pistil, unable to push through the column, bears it upon its apex
until the downward pressure is so great that the pistil bursts through,
when the elastic filaments at once draw the anthers down to their proper ”
position ona level with the limb of the corolla. The phenomenon is
attributed by the author to elasticity rather than to irritability. —

Glands on the Stamens of Caryophyllacesze.t—Prof. T. Meehan calls
attention to the existence of glands at the base of the stamens in the
chickweed and other species of Stellaria, and in Cerastiwm and Arenaria.
At times these glands exude an enormous quantity of a viscid, slightly
sweet fluid, which does not appear to have for its primary function the
attraction of insects, since the chickweed is self-fertilized, though bees
do occasionally visit these flowers for the sake either of the nectar or of
the pollen.

Fruit of Nyctagineze.{—According to Herr A. Heimerl the con-
version into mucilage of the outer layers of the fruit in this order is,
with a few exceptions, characteristic only of the Mirabilieew. The
absorption of water takes place always in a layer lying immediately
beneath the epiderm, which covers the surface of the fruit, consisting of
palisade-cells, the epiderm then peeling off. The drops of mucilage
exuded in this way sometimes contain starch-grains. The form of the
epidermal cells varies in the different groups. The author found calcium
oxalate to be a widely distributed constituent in the outer and often
also in the lateral walls of the epiderm of the fruit in the Mirabiliez ;
the form and arrangement of the particles of this salt vary greatly.

Anatomy of Leaves.§—After restating the observations of Areschoug,
Jénsson, Haberlandt, and others, on this subject, Herr O. Loebel gives
an account of his own observations, chiefly relating to details of structure
in the case of particular genera and species.

The increase of surface of the palisade-cells, brought about by
foldings of their cell-walls, the author finds to occur alike in Dicoty-
ledons, Monocotyledons, and Ferns. The walls of the palisade-cells are
composed of pure cellulose, and are usually thin; when thicker, they
are abundantly provided with pores. In both Monocotyledons and
Dicotyledons their position is occasionally oblique to the surface. The
spongy parenchyme usually contains but little chlorophyll; occasionally
starch is found in it. The parenchymatous sheath surrounding the
vascular bundles usually consists of a single row of cells from one and a
half to two times as long as broad; in some land and water plants it is
altogether wanting. In cylindrical leaves the xylem-portion of the
vascular bundles is surrounded by the phloem-portion.

* Bull. Torrey But. Club, xvi. (1889) pp. 68-9.

+ Proc. Acad. Nat. Sci. Philad., 1888, pp. 396-8.

¢ SB. Akad, Wiss. Wien, xevii. (1889) pp. 692-703 (1 pl.). Cf this Journal
1888, p. 82.

§ Jahrb. f. Wiss. Bot. (Pring-heim), xx. (1889) pp. 38-77 (2 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 545

Fixed daylight position of Leaves.*—Herr G. Krabbe agrees with
A. B. Frank in attributing the fixed position assumed by the lamina of
leaves in diffused daylight to the influence of light without the assist-
ance of geotropism or of internal forces. The experiments were made
on Dahlia, Fuchsia, Phaseolus, Pelargonium, and other plants. The
position depends on the heliotropic propertics of the leaves themselves,
and is unaffected by their weight, even when this is artificially increased.
The movements of the leaf-stalk which bring about the diurnal position
of the lamina take place only in its upper region ; and these movements,
which finally bring the surface of the lamina perpendicular to the
incident rays of light, are the result of heliotropism only. This move-
ment of the leaf-stalk is of the nature of a curvature, not of a torsion.
Torsion of the leaf-stalk is always the result of the co-operation of two
distinct forces, such as heliotropism and geotropism, in different planes.

Structure and Function of the Bladders of Utricularia.t—Herr M.
Biisgen has examined the structure of the bladders of Utricularia
vulgaris, for the purpose of determining whether they can have any
other function than that of serving for the nutrition of the plant. The
suggested purposes of protecting the plant from being devoured, and of
serving simply as swimming-organs, he finds to be inadmissible. ‘The
number of fresh-water crustacea, chiefly Cypridinee, captured is very
large, and the “antenne” and long hairs with which the bladders are
furnished are admirably contrived to assist these animals in finding their
way into the bladders. Around the entrance to the bladder are a number
of glandular hairs, from which is exuded a mucilage very difficult to
detect in the water; and this mucilage seems to be the attraction to the
animals. The cause of death of the animals is not clear; nor was the
actual digestion of their bodies demonstrated ; but a series of experiments
carried out by Herr Biisgen on plants in which animals gained access to
the bladders and on others where this was impossible, showed almost
invariably a greater vigour of growth for the former.

Stomates of Graminee and Cyperacee.t—Herr 8S. Schwendener
finds that the mechanism of the stomates of the Graminez and Cyperacex
differs to a certain extent from that of other Angiosperms. The
broadened end of the guard-cells appears to play an important part in
the process, enlarging the size of the opening by an increase of their
turgidity. Only in a few cases could any participation of the adjacent
cells in this process be detected. In those species which inhabit the
steppes, the desert, and other arid situations, special contrivances oceur
to protect the stomates from excessive transpiration ; and these are found
also in some species of Carex which inhabit marshes ; these, the author
conjectures, must be immigrants from a more northern latitude.

With regard to the systematic value of the structure of the stomates,
he finds that, while their special form in Graminee and Cyperacee is
peculiar to those orders, and marks them off sharply from the Juncacez
and other allied orders, there are other anatomical characters common
to the Cyperacee and Juncacee, and others again to the Graminee,
Cyperacez, and a portion of the Juncacee.

* Jahrb. Wiss. Bot. (Pringsheim), xx. (1889) pp. 211-60 (1 fig.).

+ Ber. Deutsch. Bot. Gesell., vi. (1888) General-Vers.-Heft, pp. lv.-lxiii.

t SB. K. Preuss. Acad. Wiss., 1889, pp. 65-79 (1 pl.). Cf. this Journal, 1882,
p- 216.

546 SUMMARY OF CURRENT RESEARCHES RELATING TO

Stomates of Coniferee.*—Herr O. Striibing describes the structure
and position of the stomates in 380 genera and 132 species of Conifere.
Juniperus is the only genus in which the species can be grouped accord-
ing to the position of these organs.

Water-pores in Cotyledons.t{— Mr. R. areal describes the distri-
bution of the water-pores on the cotyledons of a number of plants.
They are usually found on the upper surface of the cotyledon, and
when they are present, the upper surface is nearly or entirely destitute
of stomates. In several species of Campanula they are crowded on a
triangular patch near the apex of the cotyledon distinguished by its
smaller epidermal cells; they resemble the stomates in “structure, but
are smaller. In the cotyledons of Collinsia grandiflora the water-pores
open into large chambers. In those of Uriica pilulifera there is an
apical patch of very crowded water-pores on the upper surface. In
Polemonium cerulewm there are a few on the under, none on the upper
surface. In the cotyledons of Convolvulus major (Phurbites purpurea)
are large cavities surrounded by palisade-parenchyme.

Tigellum of Trees. {—M. L. Flot describes the structure of the
tigellar region of the stem of trees, which he defines thus :—TIn the plant
of one year old the cauline portion may be considered as the equivalent
of a branch of the mature tree, developing by the prolongation of a
specialized region intermediate between the stem properly so ealled and
the root. This region often includes, besides the morphological tigellum
(hypocotyledonary axis), a larger or smaller portion of the epicotyle-
donary axis, and appears to proceed from the development of organs
already formed in the embryo. This is the tigellar region.

Bacillar Tumours of the Olive and of Pinus halepensis.§—M. E.
Prillieux states that the olive may often be noticed with bacillar
tumours similar to those which have been recently described by M.
Vuillemin as growing on Pinus halepensis.|| The author gives the
details of a comparative study which he has made of these tumours,
especially from an anatomical point of view. The tubercles of Pinus
halepensis present many points of analogy with those of the olive, and
their mode of development seems to be the same. The author, however,
does not agree with M. Vuillemin when he states his belief that the
bacilli penetrate at first to the cambium, and that this meristematic layer
becomes the point of departure of ramifying canals, in the interior of
which the colonies of bacilli are inclosed. The author has examined
many young tumours, and has always found the lacune to exist in the
middle of the parenchyme. The proliferation of the cells round the
lacune is much more active in the pine than in the olive.

Tubercles on the Roots of Galega officinalis.{—Prof. F. Delpino
has examined the tubercles on the rovis of this specics of Leguminosae,
for the purpose of determining their nature and origin. On first
examining them he found the parenchymatous cells filled with the
ordinary bacteriiform bodies, in which he detected a slight motion of
translation. ‘The specimens were now planted in pure water, and again

* «Die Vertheilung d. Spaltoffnungen b. d. Coniferen,’ 8vo, Kénigsberg, 1888,
76 pp. See Bot. Centralbl, XXXVili. (1889) p. 568.

+ Anu. of Bot., iii. (1889) pp. 123-9 (5 fips).

~ Comptes Rendus, eviii. (1889) pp. 306-8. § T.¢., pp. 249-52.
| Cf. this Journal, ante, p. 243. § Malpighia, ii. (1888) pp. 385-94.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 547

examined after some days. They had put out a quantity of new roots,
but on none of these were there any tubercles. The bacterioid bodies
had now assumed the form of true bacilli, and had become elongated
and septated, and had transferred themselves into isolated somewhat
swollen cells. The tubercles he considered unquestionably as patho-
genous products of the nature of bacterioeecidia, and to have no
importance whatever in supplying nutriment to the plant. The plants
_ So affected he found produced no fruit, probably frum an insufficiency in
the supply of phosphorus and magnesia.

Tubercles of Ruppia and Zannichellia.*—Herr E. Hisinger con-
firms Goebel’s statement that the tubers frequently found on Ruppia
rostellata and Zannichellia polycarpa are caused by a parasitic fungus
(Myxomycete) Tetramyxa parasitica.

Lateral Roots of Monocotyledons.{—In continuation of his re-
searches on this subject, Sig. A. Borzi now describes the structure of
the lateral roots in Phormiwm tenawx, Agapanthus umbellatus, Dracena
Hendersoni, Cordyline stricta, Agave mexicana, and Fourcroya gigantea,
all belonging to his fourth type.

8. Physiology. {
(1) Reproduction and Germination.

Intracellular Pangenesis.§—Prof. H. de Vries proposes a modifica-
tion of Darwin’s provisional hypothesis of pangenesis. He assumes that
the nucleus of every cell usedin propagation contains all sorts of pangens
of the species of animal or plant to which it belongs. As all other
nuclei of the full-grown being owe their origin to repeated divisions of
the first, they can all be in possession of a complete set of pangens,
which can propagate themselves when a division takes place. In the
nucleus the greatest part of them remain inactive through life, with the
exception only of those pangens which determine the visible characters
of the nucleus itself, such as its special mode of division, &c. All
other organs of the protoplast essentially contain only pangens corre-
sponding to the characters which they are capable of displaying. It is,
however, by no means necessary that they should be all at all times in
an active state; thus plastids are in some cases known to exhibit alter-
nately the power of forming starch and some colouring matter. But
usually no doubt these organs contain a large number of active pangens.
Inactive pangens from the nucleus can migrate to those other organs of
the protoplast whose characters they represent; they cin again propa-
gate themselves here, and in most cases sooner or later become active,
thus bringing to light certain characters. This migration, as shown by
the facts of sexual reproduction, must occur soon after fecundation has
taken place; but there is no reason why it could not happen in many
other phases of development, perhaps even every time acell divides. This
migration of pangens may be effected by the movements of protoplasm.

* Medd. af Soc. Faun. et Flor. Fenn., xiv. pp- 53-7 (10 pls.). Cf. Bot.
Centralbl., xxxvii. (1889) p. 316. Cf. this Journal, 1885, p. 292.

+ Malpighia, ii. (1888) pp. 394-402. Cf. this Journal, 1888, p. 762.

{ This subdivision contains (1) Reproduction and Germination; (2) Nutrition
and Growth (including Movements of Fluids); (3) hritability ; and (4) Chemical
Changes (including Respiration and Fermentation).

§ ‘Die Intracellulare Pangenesis,’ 8vo, Jena, 1889, 212 pp.

548 SUMMARY OF CURRENT RESEARCHES RELATING TO

Dichogamy.*—According to Prof. T. Meehan, dichogamy (proter-
andry and proterogyny) has frequently no connection with any provision
for aiding cross-fertilization, but is dependent on the different conditions
under which the male and female organs of flowers are produced, the
male organs requiring, as a rule, a smaller degree of heat for their
maturity than the female.

Fertilization by Snails.t—Herr F. Ludwig finds that Leucanthemum
vulgare is pollinated in wet weather, in the absence of the ordinary
insect-visitors, by a nocturnal snail, Limaw levis, attracted by the white
ray-florets, on which it feeds.

(2) Nutrition and Growth (including Movements of Fluids).

Physiology of Growth. |—Herr J. Wortmann gives the details of a
number of experiments, chiefly on Butomus umbellatus and Phaseolus
multiflorus, which confirm his previous conclusions that growth is due
not merely to the force of turgidity in the cell, but partly to a force
located in the cell-wall itself. Among the more important general
results obtained are the following. The extensibility of the shoot is
greatest at its apex, gradually diminishing thence to the base. In the
entire growing region below the point of maximum growth up to that
point where growth has ceased, there is no variation in the intensity of
the turgidity, at all events not sufficient to have any effect on the
growth. The turgidity of the point of maximum growth may therefore
be regarded as constant. In the region between the terminal bud and
the zone of maximum growth there is, in the youngest cells which have
not yet begun to elongate, a rapid increase of turgidity, which becomes
less marked when the cells begin to elongate, but continues as far as the
zone of maximum growth, in which it attains its highest and constant
intensity. The production of cell-wall gradually increases from the
commencement of growth in length until the period of maximum growth,
and then gradually and slowly decreases until it reaches zero in the
mature cells.

From experiments on the growth of seeds of Lepidiwm, Herr Wort-
mann was able to confirm the theory of Sachs and de Vries that the
growth of the cell and the increase in superficies of the cell-wall depend
directly on the intensity of the turgidity and consequent tension of the
cell, the latter having for one of its factors the extensibility of the cell-
wall. The superficial growth of the cell-wall takes place mainly by
apposition, though this is sometimes assisted by intussusception.

Descending Current of Water.s—Herr J. Wiesner gives the follow-
ing demonstration of the existence of a descending current in plants.
If a cut leafy branch of the vine is immersed in water, all the succulent
parts swell up from increased turgidity; but if it is now lifted up so
that the leaves are elevated above the water while the apex of the shoot
still remains submerged, this latter becomes flaccid, which can be
accounted for only by the sap having passed out of it by a descending
current into the lower leaves. Although this descending current has not

* Proc. Acad. Nat. Sci. Philad., 1888, pp. 391-4.

+ SB. Gesell. Naturf. Freunde Berlin, 1889, pp. 16-8. See Bot. Centralbl.,
XxxXvii. (1889) p. 392.

t Bot. Ztg., xlvii. (1889) pp. 229-39, 245-53, 261-72, 277-88, 293-304 (7 figs.).
Cf, this Journal, 1888, p. 615. § Bot. Ztg., xlvii. (1889) pp. 1-9, 24-9.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 549

nearly the importance of the ascending current, it is not without physio-
logical significance to the plant. The author states that it has a
definite influence in the opening of many flowers and inflorescences, in
consequence of the passage of water from the flowers themselves into
the foliage beneath them, in the formation of sympodial leafy shoots,
terminal and axillary buds, &e.

Influence of Light on the Development of Bark.*—M. H. Douliot
finds that the development of bark does not depend in any way on the
action of gravitation, the under and upper sides of a horizontal branch
being quite homogeneous when equally illuminated. But on an erect
stem the development of bark is always greater on the south side, which
receives a larger amount of light, than on the north side. The author
suggests that this may be due to greater transpiration, moisture acting
unfavourably on the formation of periderm.

Periodical Activity of the Cambium in the Roots of Trees.t—By
observations made on seventeen species of trees belonging to the
Dicotyledons and Conifers, Herr L. A. Gulbe has determined that the
activity of the cambium begins in the spring in the slender branches,
advgnces from there to the trunk, then into the thicker, and finally into
the slender roots, about four or five weeks from the commencement of
the activity. In the autumn the decrease of activity takes place in the
same period, varying within about two months, and finally ceasing in
the second half of October,

Penetration and Escape of Gases in Plants.t—M. L. Mangin gives
the following summary of the laws which regulate the penetration and
exhalation of gases in plants.

The diffusion through cutinized surfaces is independent of variations
in temperature within the limits of the plant; it is, fur each gas, pro-
portional to the difference of the pressures which the gas exercises on
the two surfaces of the membrane. The rapidity of diffusion varies with
different gases. The coefficient of permeability, i.e. the amount of
carbon dioxide diffused per hour and per square cm. of surface, is
greater in the case of submerged than of aerial leaves; when the two
surfaces of the leaf are unlike, it is usually greater on the lower than on
the upper surface. The permeability does not depend on the thickness
of the cuticle, but altogether on the extent to which it is impregnated
with wax, a certain amount of waxy matter being present on all leaves,
whether submerged or aerial. The duration of the life of leaves influ-
ences their permeability, deciduous being often more permeable than
persistent leaves; other things being equal, the number or size of the
stomates increases in proportion as the permeability decreases. The
closing of the stomates by a covering which preserves intact the permea-
bility of the membranes diminishes the exchange of respiratory gases
from one-fifth to one-half; but the diminution ceases when the tem-
perature is low; it is greatest with young and deciduous leaves. The
diminution of respiration on the closing of the stomates is due entirely
to the insufficient supply of oxygen. The process of assimilation is also

* Journ. de Bot. (Morot), iii. (1889) pp. 121-4 (8 figs.).

+ Arb. St. Petersburg. Naturf. Gesell, xviii. p. 45. See Bot. Centralbl., xxxviii.
(1889) p. 487. ;

¢ Ann. &ci. Agron. Frang. et Etrang., i. (1888). See Journ. de Bot. (Morot), iii.
(1889) Rev. Bibl., p. iv. Cf. this Journal, 1888, p. 763.

550 SUMMARY OF CURRENT RESEARCHES RELATING TO

hindered by the closing of the stomates from the reduction of the supply
of carbon dioxide. The coefficient of permeability of membranes is
usually, except for respiration at low temperatures, too low for the
exchange of gases to take place with its normal intensity; hence the
need of stomates for aerial plants.

Assimilation of Free Nitrogen by the Lower Organisms.*—In
pursuance of previous investigations on this subject, Herr B. Frank
claims to have determined experimentally that very low algal (or pro-
tophytal) forms of life, such as Oscillaria, Ulothria, Pleurococcus, Chloro-
coccum, and the protoneme of mosses, have the power of removing the
free nitrogen from the atmosphere and forming therefrom nitrogenous
compounds. This property he believes therefore to be common to all
vegetable organisms which contain chlorophyll, and that, in all pro-
bability, it is, like the assimilation of carbon, a function of their proto-
plasm. Whether the chlorophyll-pigment takes any part in the process
must remain at present undetermined.

(4) Chemical Changes (including Respiration and Fermentation).

Respiration of the Fig.t—Dr. C. Lumia has examined the composi-
tion of the gas contained within the immature receptacle (fructification)
of Ficus carica, and finds it to consist of about 5°25 per cent. CO,,
17:9 per cent. O, and 76°83 per cent. N. The proportion of carbon
dioxide is therefore about 130 times that present in the atmosphere,
showing that respiration must take place within the cavity of the fig
with extraordinary energy.

Process of Oxidation in Living Cells.t| —Herr W. Pfeffer argues
against the existence of either ozone or hydrogen peroxide in the living
cell, on the ground that even the smallest quantities of the former
substance are fatal, while the latter rapidly colours the tissues a red-
brown in consequence of a process of oxidation, but without destroying
the activity of the protoplasm. There are, however, some tissues which
are not coloured in this way. Cells containing a soluble pigment are
bleached by the oxidation of the pigment.

Oxalic Fermentation.s—Herr W. Zopf finds in beer-wort-gelatine a
Schizomycete to which he gives the name Saccharomyces Hansen, which
forms endogenous spores, and which possesses the remarkable property
of producing oxalic acid instead of alcohol. This is the result of the
fermentation of carbohydrates belonging both to the grape-sugar and to
the cane-sugar group.

y. General.

Young State of Plants.||—Prof. K. Goebel contrasts the mature and
the young forms in a number of illustrations drawn from the higher
families of the vegetable kingdom, viz.:—Floridez (especially Lemanea
and Batrachospermum), Musci (especially Sphagnum, in which he finds
invariably a flat prothallium, whether the spores germinate in water
or not), Hepatice, Pteridophyta, and Phanerogamia. As a general rule,
when the early differs from the mature form of a plant, it must be

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 84-42. Cf. this Journal, ante, p. 412.
+ Nuoy. Giorn. Bot. Ital., xxi. (1889) pp. 317-20.

{ Ber. Deutsch. Bot. Gesell., vii. (1880) pp. 82-9. § T.¢., pp. 94-7.

\| Flora, xxii. (1889) pp. 1-45 (2 pls. and 6 figs.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 551

regarded as resulting from an arrest of development, frequently repro-
ducing the form which the whole plant originally possessed. In many
plants this youthful form disappears rapidly and at a very early period ;
while in others it remains for a very considerable time, according to the
external conditions of life.

‘“‘Tan-disease”’ of Cherries.*— Dr. P. Sorauer describes a new
disease of cherries similar to the well-known “ tan-disease” of apples,
which has made its appearance in Germany as the result of a wet
summer. It manifests itself in the excessive development of the lenticels
by the formation of fresh layers of cork beneath those previously in
existence, and by a subsequent copious formation of gum. The latter
appears to be the result of a great local accumulation of water and of
formative substances.

Diseases of Trees.t—Dr. R. Hartig has published a second edition of
his ‘ Text-book of the Diseases of Trees,’ including those due to all
causes :—external injury, unfavourable conditions of life, and the attacks
of parasites, whether phanerogamic or cryptogamic. Among destructive
fungi he describes in particular Melampsora Tremule, which attacks
both the Scotch fir and the larch, Phoma abieiina on the silver fir,
Trichosphzeria parasitica and Herpotrichia nigra, which are very de-
structive to forest-trees, Pestalozzia Hartigii, and many others,

B. CRYPTOGAMIA.
Cryptogamia Vascularia.

Aluminium in Vascular Cryptogams. {—Prof. A. H. Church finds
aluminium to be a constant constituent of the ash of some species of
Lycopodium, while it is entirely absent from others. Among other
Vascular Cryptogams, the genera Hquisetum, Ophioglossum, Salvinia,
Marsilea, Psilotum, and Selaginella gave negative results; it was found
only in the ash of some tree-ferns, but is an important constituent of
the water-moss Fontinalis antipyretica. It occurs in combination with
organic acids, and may serve to neutralize the acids produced in the
plant.

Germination of the Megaspore of Isoetes.s—According to Mr. J. B.
Farmer, the coat of the megaspore of Isoetes lacustris consists of six
layers :—the epispore, derived from the epiplasm of the megasporange, a
colourless, glassy, and brittle layer, whose surface is beset with numerous
irregular prominences ; the exospore, composed of three brown cuticu-
larized layers; and the endospore, composed of two layers of cellulose.
The protoplasm of the megaspore is remarkably granular, and contains
a large quantity of starch and oil, and a sharply differentiated nucleus.
The first indication of cell-division in the formation of the prothallium
is the appearance of a very thin membrane of cellulose derived directly
from the protoplasm, which cuts the spore into a basal and an apical
portion ; while the former for some time undergoes no change, the latter

* Bot. Ztg., xlvii. (1889) pp. 181-6.

+ ‘Lehrb. d. Baumkrankheiten,’ 2 Aufl., 137 figs. and 1 coloured pl., Berlin, 1889.
See Bot. Ztg., xlvii. (1889) p. 272.

~ Proc. Roy. Soc. Lond., xliv. (1888) pp. 121-9.

§ Op. cit., xlv. (1889) pp. 306-8, and Ann. of Bot., iii. (1889) pp. 131-4.

bbz SUMMARY OF CURRENT RESEARCHES RELATING TO

is divided very rapidly into a number of cells whose arrangement can
still be followed even in quite old prothallia. The rudiments of the
archegones make their appearance very much as in Marattiacee; the
neck being first formed by periclinal division, then the neck-canal-cell ;
and finally the ventral canal-cell is cut off from the oosphere, when the
canal-cells thrust themselves between the neck-cells.

Antherozoids of Ferns.*—M. L. Guignard has investigated the mode
of development of the antherozoids in a number of genera of ferns, viz.
Adiantum, Gymnogramme, Pteris, Pellea, Aspidium, and Asplenium be-
longing to the Polypodiacez, Osmunda among the Osmundacez, and
Angiopteris among the Marattiacez.

The processes are, in all essential points, identical with those in the
Characeze t and Muscinee. The antherozoids are larger than those of
the Muscinee, and are provided with a larger number of cilia; they
proceed from rounded or ovoid mother-cells. The nucleus transfers
itself, before it becomes transformed into an antherozoid, from a central
to a lateral position. The mature antherozoid consists of from two to
three turns of the spiral; its anterior extremity has the form of a beak;
this portion being comparatively thin, the posterior portion thicker ;
the latter carries, when the antherozoid escapes, a vesicle which contains
starch-grains and the residue of the nutritive protoplasm. The forma-
tion of the cilia takes place at an early period; the hyaline layer of
protoplasm which covers the outer surface of the nucleus developes into
an annular band inclosing the granular protoplasm. This layer is more
extensive than in the lower Cryptogams, corresponding to the greater
number and length of the cilia. The formation of these latter commences
at the anterior end of the antherozoid, and is rapidly completed along
their whole length, which somewhat exceeds that of the adult body.
They are inserted in a tuft on the anterior half of the first turn of the
spiral.

Stem of Ferns.t—M. Leclerc du Sablon describes the difference
between the structure of the root and the stem in Pteris aquilina. These
results agree in all essential points with those obtained by M. Gérard in
Asplenium striatum and A. cuneatum. Near the base of the stem the
smaller vessels of the wood lie towards the exterior, as in the root,
but this arrangement is somewhat altered by the insertion of the leaves.
The central cylinder of the stem is formed by a .xylem-portion at the
centre, a ring of phloem round the xylem, and a layer of pericycle round
the phloem. Soon this structure is somewhat modified. Towards the centre
of the xylem-portion phloem-elements appear, and this phloem gradually
increases. In the stem there is then at the centre the phloem, then a
ring of xylem, then a ring of phloem, then the pericycle. A comparison
has been made between the stem of Ferns and that of Auwricula ; in all
these plants the thickening of the stem is not effected by secondary
formations, but by successive divisions of the central cylinder. The
same general results were presented by other ferns,

Varieties in Ferns.s—Mr. E. J. Lowe has observed, in the case of
Scolopendrium, that the same prothallium will sometimes produce two

* Comptes Rendus, cviii. (1889) pp. 464-6, and Rev. Gén. de Bot. (Bonnier), i.
(1889) pp. 71-8 (1 pl.). t Cf. this Journal, ante, p. 417.

+ Bull. Soc. Bot. France, xxxvi. (1889) pp. 12-4.

§ Ann. of Bot.,-iii. (1889) p. 129.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 5538

plants which both exhibit the same marked and identical variation in
their character.

Rabenhorst’s Cryptogamic Flora of Germany (Vascular Crypto-
_gams).*—This volume of this important publication is now completed
by the publication of parts 11-14. These include the completion of the
Equisetaces, in which twelve species of Hquisetum and a large number
of varieties are very fully described, divided into the “ phaneropora ”
and the “cryptopora.” The isosporous Lycopodinee include the two
orders Lycopodiacez and Isoetacvee, each with a single genus, Lyco-
podium and Isoetes, the former comprising six, the latter two species.
Finally the Selaginellacez include the single genus Selaginella with
three species. Throughout this most valuable work the descriptive
letterpress and the woodcuts leave nothing to be desired.

Tubicaulis.t—Prof. G. Stenzel publishes a monograph of the species
of fossil herbaceous ferns, several of them new, which may be referred
to Corda’s genus Tubicaulis, but which are now distributed through
that genus, Asterochlena, Zygopteris, and Anachoropteris. The genus
Tubicaulis in its restricted sense now includes only TJ’. Solenites, dis-
tinguished by its cylindrical central vascular bundle. In Asterochlena
the bundle is lobed in a radiate manner, and the leaf-stalk-bundles are
ribbon-shaped in transverse sections. Zygopteris has a tubular central
bundle filled with medullary parenchyme and with five projecting ridges,
the leaf-bundles having a peculiar H-form in transverse section. A new
species, Z. scandens, is described, the slender stems of which creep into
the envelope of the root of Psaronius, where they carry on an epiphytic
existence. The greater part of the leaves are reduced to short scales,
while above each leaf, springing apparently from the stem, is a short
cylindrical lateral shoot. Anachoropteris is distinguished by the convex
form of the transverse section of the vascular bundles.

Muscinez.

Leptotrichic Acid.{—-The glaucous appearance of Leptotrichum glau-
cescens is caused by a white scurfy coating, which protects it from the
action of water like a coating of wax. Herr J. Amann finds this sub-
stance to be very soluble in ether, chloroform, or hot alcohol. From
the acid solution in ether leptotrichic acid crystallizes out on evapora-
tion in the form of prismatic needles. It is scarcely affected by con-
centrated sulphuric or hydrochloric acid, or by caustic alkalies in the
cold. The author finds this substance present in the green parts of
the moss to the extent of 13 per cent. of its weight, and believes it to be
the first crystallizable substance as yet found in the Muscinee.

Mosses from New Guinea.$—Herr A. Geheeb describes the mosses
collected in New Guinea, mostly on the Fly river, by Biuerlein, in
Captain Evvill’s expedition. Out of the twenty-seven species about
eighteen are new, but belong to familiar genera.

* Luerssen, C., ‘Die Farnpflanzen (Pteridiophyta),’ 8vo, Leipzig, 1889, xii. and
906 pp. (228 figs.).

+ Uhlworm u. Haenlein’s Biblioth. Bot., 1889, Heft 12, 50 pp. and 7 pls.

t Bot. Centralbl., xxxvii. (1889) pp. 71-2.

§ Uhlworm u. Haenlein’s Biblioth, Bot., 1889, Heft 13, 12 pp. and 8 pls.

554 SUMMARY OF CURRENT RESEARCHES RELATING TO

Antherozoids of Hepaticee and Mosses.*—In all the Hepatice ex-
amined, belonging to very different types of structure—Pellia, Anthoceros,
Frullania, Marchantia, &e.—M. L. Guignard finds the mode of develop-
ment of the antherozoids to agree in all important points. Pellia
epiphylla may be taken as a type.

The mother-cells of the antherozoids have a discoid form, one side
being flat and the other slightly convex; they remain attached in pairs
by their flat faces until the maturity of the antherozoids, which are
formed singly in each of them. In the formation of the antherozoid the
nucleus of the mother-cell, at first central, moves to one side, and is
covered only by a very thin layer of protoplasm. It now elongates
greatly, and curves in a spiral manner; its anterior extremity, always
very thin, is in close juxtaposition to the thick posterior extremity ;
finally the spiral attains three or four turns. The thin layer of
protoplasm which covers the outer surface of the nucleus becomes a
hyaline band which is continued as far as ihe opposite side, surrounding
the granular protoplasm. From it are formed the two cilia which
proceed from the anterior end of the antherozoid, and rapidly attain
their full length, which is equivalent to that of the spiral. The granular
protoplasm comprised in the spiral is gradually absorbed as the anthero-
zoid developes; a very few traces only remain at the period of maturity.
The differences observed in other Hepaticze concern only the form and
size of the mother-cells, and the length of the cilia compared to that of
the spiral.

The processes of development in the Musci are completely analogous
to those in the Hepatic. In Sphagnum the body of the mature anthero-
zoid consists of only two turns of the spiral, of which the first is much
the larger, and, when escaping from the mother-cell, carries with it a
residue of protoplasm in the form of a vesicle inclosing some granula-
tions and a small quantity of starch. The two cilia, inserted at the
anterior extremity, which has somewhat the appearance of a button, are
always rather longer than the body of the antherozoid.

The mode of formation of the antherozoids of the Muscinez agrees
therefore, in all essential respects, with that of the Characee.f It is
the nucleus only which is transformed directly into the body of the
antherozoid; the cilia being formed, at an early period, from a hyaline
layer of protoplasm outside the nucleus. The spiral body is homo-
geneous and chromatic, except in the posterior portion, where it is
somewhat less receptive to nuclear reagents. It is covered by a very
delicate hyaline envelope.

Geotropism of the Rhizoids of Marchantia and Lunularia.{ —
From a careful series of observations on the development of the rhizoids
proceeding from the bulbils of Marchantia and Lunularia, Herr H.
Haberlandt states that growth in length takes place exclusively in the
cap-shaped apical portion of the rhizoid, where it is manifested with
extraordinary energy. ‘The geotropic curvature is not exhibited, as has
been stated, in a zone of the rhizoid below this growing portion, but in
the growing portion itself. Under the influence of geotropism the
rhizoids never assume a vertical direction, but make an angle of from

* Comptes Rendus, evili. (1889) pp. 463-4, and Rey. Gén. de Bot. (Bonnier), i.
(1889) pp. 63-70 (1 pl.). + Cf. this Journal, ante, p. 417.
¢ Oesterr. Bot. Zeitschr., xxxix. (1889) pp. 93-8.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 555

50° to 70° with the vertical. Neither in the growing nor in the mature
portion of the rhizoid could the author detect the least evidence of any
variation in the thickness of the cell-wall, or in the distribution of the
protoplasm on the two sides of the growing organ.

Algee.

Connection of the geographical distribution of Alge with the
chemical nature of the substratum.*—Sig. A. Piccone points out the
argument in favour of the view that Algz do not absorb nutriment
through their organs of attachment derived from the fact that the same
species will be found growing apparently indifferently under totally
different circumstances. He gives a list of 17 species ordinarily rupi-
colous which are found not unfrequently attached to the shells of
molluses or growing epiphytically upon other sea-weeds, and of two
species ordinarily fucicolous which he found attached to a variety of
other sea-weeds belonging to the Floridez and the Chlorosporee.

Algz of the ‘Gazelle’ Expedition.t—The Alg collected in this
expedition have been worked out by Herr H. Askenasy, with the assist-
ance of M, Bornet and Herren Grunow, Hariot, Moebius, and Nordstedt.
The following new species are described :—Cyanophycee :—Microcheete
vitiensis. Conjugate :—Gymnozyga longicollis. Confervaces: :—Ana-
dyomene reticulata. Characezw :—WNitella dualis. Siphonocladacex :—
Halimeda macrophysa, Caulerpa delicatula. Pheeophycee :—Ectocarpus
Constancize. Fucaceze :—Cystophyllum nothum, Sargassum pulchellum,
S. Mauritianum. Floridex :—Hildebrandtia Lecannellierit, Chantransia
Naumannii, Rhabdonia decumbens.

Dictyosphzxria farulosa consists of large cells, 0: 5-2 mm. in diameter,
between. which are several rows of smaller cells; the structure of the
walls of the latter is very peculiar. Young plants have the form of a
closed sac, resulting from the segmentation of large cells, containing
numerous nuclei, starch-grains, and peculiar brown elliptical bodies.
The structure of Halimeda is described in detail. Among the Meso-
gloeaceze the author regards the genus Myriocladia as hardly sufficiently
distinct from Mesoglea. In Galawaura (Chetangiacee) the structure
recalls that of Halimeda. Straight branching medullary hyphew send
out branches at right angles which end in the cortical fibres. The only
fructification observed consisted of cystocarps. In Corynospora Wiiller-
storfiana (Ceramiace) polyspores were observed closely resembling those
of Pleonosporium. Marchesettia spongioides (Areschougiacee) the author
regards as undoubtedly furnishing an example of symbiosis between a
Floridea and a sponge. The species of sponge probably varies. The
only reproductive organs observed were tetraspores.

Development of Tissues in Floridew.{—Prof. N. Wille gives more
detailed illustrations of the six groups into which he divides the Floridez,
dependent on the mode of growth of the frond and the development of
the different tissues.

* Notarisia, iv. (1889) pp. 667-71.

+ Algen (Forschungsreise 8.MLS. Gazelle), Th. 4, Botanik, Berlin, 1888, 58 pp.
and 12 pls. See Bot. Centralbl., xxxvii. (1889) p. 112.

t Nova Acta K. Leop.-Carol. Akad., lii. (1888) pp. 49-100 (6 pls.). Cf. this
Jounal, 1886, p. 658.

556 SUMMARY OF CURRENT RESEARCHES RELATING TO

Frond of Polysiphonia.* — Herr L. K. Rosenvinge contests the
theory of Schwendener that the spiral arrangement of the “leaves” of
Polysiphonia is brought about by contact of these organs with the axis
which bears them. In P. violacea he found no such contact, even at the
earliest period. The “leaves” of the lateral shoots of many species of
Polysiphonia are from the first arranged in a regular sinistrodromal
spiral not resulting from any contact.

The cells of many Floridez are united by pores formed apparently
at the same time as the walls which they perforate. In several species of
Polysiphonia, especially in P. violacea, the author finds in addition, and
in the pericentral cells, “secondary pores” formed in a very remarkable
way. The young cell contains a rather large nucleus, which soon
divides into two, the lower of which lies on the lower and outer
angle of the cell. A small triangular piece of the cell containing this
nucleus is now cut off by an oblique wall, and this segment passes
through the underlying wall, and coalesces with the subjacent cell. Tits
nucleus passes into the underlying cell, but a fine strand of protoplasm
remains uniting it with the protoplasm of the cell from which it was cut
off; and the pores through which these strands pass are the secondary
pores. The author compares this process with a similar one in the
Hymenomycetes.

Apical cell of Lomentaria and Champia.j—According to Prof. N.
Wille there is in Lomentaria kaliformis only a single apical cell, from
which segments are cut off in different directions. This is to some
extent at variance with the observations of Debray and others.{ The
branches are hollow with transverse diaphragms. The outer wall con-
sists only of two primary layers, the outer of which afterwards gives rise
to the small cells filled with endochrome. In older branches these cells
expand into a connected layer outside the outermost primary layer.
The inner of the two primary layers constitutes a conducting system ;
but the cells of this system originate by tangential division of young
cells of the outer layer. In the centre of the apex is a large cell which
has probably been formed from the apical cell of the outer layer by a
division parallel to its base. This apical cell is polygonal, and from it
are separated daughter-cells in six directions.

Prof. J. G. Agardh § agrees generally with the view of Wille that
the cells of the outer layer in the frond of Lomentaria and Champia
originate from the outer cells of the inner layers. These internal layers
put out outwardly ramifications which form the outer parenchyme of the
thallus, and inwardly ramifications which form the diaphragms.

Bulb of Laminaria bulbosa.||—Mr. C. A. Barber has investigated
the structure of the stem of this sea-weed, which differs from that of
other species of the genus. It is characterized by the peculiar bulb-like
enlargement of the base which is attached to the substratum by several
successive circular rows of “ hapteres,” and by its bearing sporanges on
the “buib.” While in other species of Laminaria the hapteres arise as

* Bot. Tidskr, xvii. (1888) pp. 1-19 (1 pl.). See Bot. Centralbl., xxviii. (1889)
. §28, 529.
me + Bot. Notiser, 1887, p. 252. See Bot. Centralbl., xxxvii. (1889) p. 420.
t Cf. this Journal, 1888, p. 265.
§ Ofv. K. Vetensk Akad. Forhandl., 1888, pp. 49-68.
\| Ann, of Bot., iii. (1889) pp. 41-64 (2 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 557

emergences, and appear in ascending order in more or less regular
series, in L. bulbosa, they are developed on the bulb, the stalk, and the
basal parts of the lamina. The stalk may be divided into five regions,
viz.:— (1) the primary fixing-organ, (2) the bulb, (8) a flattened
twisted portion, (4) a portion with flounced edges, and (5) a flat straight
piece which passes upwards into the lamina. The principal purpose of
the bulb appears to be the fixing of the plant to the sea-bottom. It also
serves to produce sporanges; so that, if the rest of the plant is torn
away by storms, there is still left in the bulb the power of assimilation
and of reproduction. LL. bulbosa is probably an advanced type, with a
large amount of differentiation and complicated attempts at adaptation.

Contraction of the Chlorophyll-bands of Spirogyra.*—Herr H. de
Vries finds that several species of Spirogyra (notably S. communis and
nitida), when the filaments hibernate, have the chlorophyll-bands con-
tracted ; but that this is not the consequence of injury is shown by the
continued turgidity of the cell and movement of the protoplasm-granules,
as well as by the impermeability of the tonoplasts to eosin and plas-
molytic reagents during the contraction. When the contraction of each
separate band begins at one or at both ends, the bands simply break up
into small portions which lie on the line of the original bands. But
when, in a compound spiral, like that of S. communis, the middle coils
contract, while the outer ones retain their original position, the cylin-
drical tonoplast becomes more or less deeply constricted in a variety
of ways.

Variation in Desmids.;—M. E. De Wildeman describes and figures
a number of varietal forms of species belonging to the genera Micrasterias
and Euastrum, and believes that a large number of these variations are
the result of reduplication or division, especially when this takes place
before the half-cells have attained thtir full development. He considers
also that it is impossible to ignore the existence of geographical races of
the same species.

Spongocladia.t—Messrs. G. Murray and L. A. Boodle referring to
Marchesetti’s observations § on the symbiotic relationship of a sponge
and an alga in the case of Marchesettia spongioides, consider that this
discovery confirms the probability of a similar phenomenon being
presented also by Spongocladia.

Urospora.||——Herr G. Woltke does not agree with Areschoug’s later
identification of his Urospora mirabilis with the genus Hormiscia, but
regards it as constituting a distinct genus of Ulotrichacee. It grows on
rocks which are occasionally sprinkled with salt water. The filament
is unbranched, and consists of cylindrical thick-walled cells of very
variable size and form. One or more basal cells, of greater length but
smaller breadth, and destitute of chlorophyll, constitute a rhizoid. The
green cells contain a single chromatophore which encloses a number of
pyrenoids. The megazoospores are pear-shaped, with 4 cilia at their
broader colourless rounded end, from 14°5 to 25 w long, and from 5:8
to 9 » broad, a large number being contained in a mother-cell, where

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 19-27 (1 pl.).

+ Bull. Soc. R. Bot. Belgique, xxvi., part i., 1887 (1889) pp. 271 88 (1 pl.).

t Ann. of Bot., iii, (1889) pp. 129-31. Cf. this Journal, 1888, p. 1002.

§ Cf. this Journal, 1885, p. 282. :

|| Schrift. Neurussisch. Naturf. Gesell. Odessa, xii., 53 pp. and 2 pls. See Bot.
Centralbl., xxxviii. (1889) p. 483.

1889. 2Q

558 SUMMARY OF OURRENT RESEARCHES RELATING TO

they are formed by successive bipartitions. On germinating, the ante-
rior colourless end developes into the rhizoid. Under unfavourable
vital conditions Urospora forms resting-cells.

Chionyphe.*——According to Dr. G. B. de Toni, this genus of snow-
Alge proposed by Thienemann, is nothing but the protoneme of a
moss, probably an Andrexa or Bryum. The genus Kurzia of Martens
again, possibly consists of the very reduced leaves of a Jungermannia.

Crenacantha, previously identified by de Toni with Bulbochete, he
now regards as more probably belonging to the Cladophoracez, possibly
near Chloropteris Mont.

Avrainvillea.{—Messrs. G. Murray and L. A. Boodle give a diagnosis
and monograph of this tropical genus of Multinucleate, with which they
identify Lhipilia and Chlorodesmis, placing it near to Penicillus and
Udotea, from which it differs in the absence of any calcareous incrusta-
tion. Nine species are described, one of them new. The mature plant
is, when not in a reproductive condition, almost absolutely non-cellular.
The filaments are dichotomously branched, and are more or less inter-
woven, so as to form a stalked or sessile frond above, a mass of
rhizoids below; the filaments are constricted, and very rarely septated,
near their base. The protoplasm forms in most cases a rather thin
parietal layer, through which are distributed the chlorophyll-grains and
a very large number of nuclei, which are usually considerably larger than
the chlorophyll-erains and much more granular. A yellowish or
brownish colouring-matter is distributed through the protoplasm. The
frond is always more or less flabelliform, and usually more or less
felt-like in texture. The mode of reproduction was not observed. ‘The
authors suggest that the gigantic fossil siphoneous alga Nematophycus,
from the Devonian, was possibly allied to Avrainvillea.

Cellulose-fibres of Caulerpa.t—Herr F. Noll proposes a different ex-
planation from that hitherto accepted for the fibres or bands of cellulose
found within the greatly enlarged cell of Caulerpa prolifera. He shows,
from various considerations, that their purpose cannot be the mechanical
strengthening of the organism, and adduces evidence in favour of the
view that they serve as a channel for the conveyance of nutrient sub-
stances more rapidly than this can take place through the protoplasm.
They serve in fact the purpose of intervening a large surface between
the internal protoplasm and the atmosphere, and may be compared with
the external protuberances from the greatly enlarged cell of Codiwm.
Caulerpa presents in this way the greatest differentiation of structure to
be found in any non-cellular plant. The division into cells of the cellular
plants must be regarded mainly as a contrivance for the same purpose,
the easy transference of food-material, rather than as a splitting up into
physiological units.

Volvox.§—Dr. L. Klein makes a further contribution to our know-
ledge of the morphology and life-history of this genus, his observations
having been made chiefly on V. aureus Khrb. (= V. minor Stein).

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 28-30.

+ Journ. of Bot., xxvii. (1889) pp. 67-72, 97-101 (2 pls.).

} Arbeit. Bot. Inst. Wiirzburg, iv. (1888) pp. 459-65.

§ Jahrb. Wiss. Bot. (Pringsheim), xx. (1889) pp. 133-210 (3 pls.). Ber. Deutsch.
Eel. Gesell., vi. (1888) Gen.-Vers.-Heft, xcix.-ci. Op. cit., vii. (1889) pp. 42-53
(1 pl.).

ZOOLOGY AND BOTANY, MIOROSCOPY, ETO. 559

Both this species and V. globator vary remarkably in the size and
number of the cells of which the colony is composed, in the size of the
colony, and in the number of daughter-colonies, oospheres, oosperms, and
bundles of antherozoids ; while the size and form of the oosperms are
nearly constant in both species. The two species are best distinguished
by the form of the separate cells, and by the fact that the cells of
V. aureus are always at a considerably greater distance from one another
than those of V. globator. The separate cells of V. awreus are roundish
when seen from the surface, and are connected with one another by
extremely fine threads of protoplasm which are interrupted in the
middle ; while the much smaller cells of V. globator are angular in
outline, and are connected by much stouter threads of protoplasm
which are also interrupted. The colonies of V. awreus have very com-
monly an ellipsoidal or lemon-form. The protoplasts are invested
by a thick gelatinous membrane which does not show the reactions
of cellulose ; the interior of the ccenobe is not filled with water, but
with jelly.

When the daughter-families are being formed, the mother-colony
remains passive. ‘The movement of the colony is the result of rotation
round an axis oblique to the path of motion. The young oospheres are
connected with the adjacent vegetative cells by a number of connecting-
threads. The bundles of antherozoids are formed from their mother-
cells by radial division, just as the daughter-families are formed from
the parthenogonids and germinating oosperms; the number of these
bundles may amount, in the purely male colonies, which are known
as Spherosira Volvox, to over 1000; the antherozoids always escape
in bundles, which are formed in succession, and only separate later and
gradually.

Volvox aureus is neither purely non-sexual and diccious, nor purely
non-sexual and moneecious-proterogynous, but displays almost all possible
combinations in the distribution of the sexes; Dr. Klein enumerates as
many as ten of these combinations. The coenobe must be regarded, from
a physiological point of view, as an example of commensalism for the
purpose of nutrition, and the author compares it to a bee-hive, where a
small number of individuals, which are exclusively concerned with the
reproduction of the species, live on the labour of the rest ; the partheno-
gonids, the oospheres, and the bundles of antherozoids, are nourished by
the vegetative cells. The reproductive organs always lie in the part of
the colony which is posterior when in movement.

The alternation in the appearance of the sexual organs coincides with
the changes of the seasons. In the spring there are found chiefly non-
sexual or purely dicecious colonies, in the summer antherozoids only in
otherwise vegetative colonies, in the late summer and autumn also the
moncecious-proterogynous families, and vegetative colonies. The alterna-
tion of generations may close either, as is usually the case, with dicecious
purely sexual, or with moncecious-proterogynous colonies.

From considerations derived from the history of development,
Dr. Klein regards the bundle of antherozoids of Volvox not as an
antherid, but as a male colony, and as homologous with an entire
ccenobe; each antherozoid invested in its envelope of mucilage is an
antherid, and homologous with an oogone and its single oosphere. It is
possible to have three generations, one inclosed within another, and all
fully developed.

2-@ 2

560 SUMMARY OF CURRENT RESEARCHES RELATING TO

Nematophyton.*—From a careful examination of the remains of the
fossil forms known as Prototaxites and Nematophyton (Nematophycus
Carruth.), from the Devonian strata of Gaspé, including those of a new.
species, Sir W. Dawson and Prof. D. P. Penhallow confirm the conelu-
sions of Carruthers, that they are the remains of a gigantic alga probably
nearly allied to the Laminariacez.

Fungi.

Fungus-pigments.{—Herr W. Zopf has examined the composition
and properties of a number of pigments obtained from Fungi, Myxomy-
cetes, and Schizomycetes, of which the following particulars are now

ven.
is Several fungi contain a pigment nearly allied to gamboge. It was
obtained especially from Polyporus hispidus, which is not uncommon on
trees. It consists of two substances, one a yellow resin insoluble in
water, the other a soluble yellow-green pigment with acid properties.
The chemical properties of the former substance are given in detail,
agreeing closely with those of that obtained from Garcinia.

From the fructification of several species of Thelephora a pigment
was obtained, which isa mixture of at least three different substances,—
thelephorie acid, of a beautiful red colour, crystallizing in blue erysials ;
a yellow uncrystallizable acid, soluble in water; and a yellow resin.
They are found both permeating the cell-membranes and as products of
excretion, and the last also as a cell-content.

The beautiful red colour of Trametes cinnabarina is due to a mixture
of a substance crystallizing in beautiful cinnabar-red erysials, and of a
resin. The former the author proposes to call xantho-irametin.

In Bacterium egregium, and possibly also in other Schizomyceies
and Myxomycetes, Herr Zopf finds a lipochrome or oil-pigment,
analogous to the anthocyan of flowering plants, the formation of which
is not dependent on the presence of light.

Musk-fungus.{—Dr. 8. Kitasato has found in hay infusions a
mould-fungus which gave out a peculiar odour of musk. He was able
to cultivate it on extract of meat-peptone-gelatin, agar-agar, bread,
potatoes, rice, and in a number of infusions. On a solid subsiraium the
mycele was at first white, afterwards reddish, and finally scarlet, with
cockscomb-like projections, giving out a distinct odour of musk.

The development of the mycele ean be readily followed out under
the Microscope. Ii consists at first of crescent- or sickle-shaped bodies,
7-13 p long, and 1-1’5 p broad at the broadest part, with a dividing-
line in the middle. At an ordinary temperature of 15-18° C., after
about 12-15 hours, a germinating-tube proceeds out of each end of the
crescent-shaped bodies, soon attaining a considerable length, and putting
out protuberances, which develope into the unilateral branches which
give the comb-like appearance to the mature form. From the filaments
are finally produced crescent-shaped protuberances which become
detached and remain after the rest of the filament has perished.

On a solid substratum the filaments become septated into short
segments, which form oidium-like bodies of a sausage-shape. These

* Trans. Roy. Soc. Canada, vi. 1888 (1889) pp. 27-47 @ pls).
+ Bot. Ztg., xlvii. (1889) pp. 54-61, 69-81, $5-92 (1 pl).
$ Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) pp. 365-9 G figs.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 561

round themselves off at the two ends, which become separated from one
another, and then act as true arthrospores, a germinating-filament
proceeding from each. The fungus is a Fusisporium, and the author
calls it F. moschatum. It appears to have no pathogenous properties.

New Entomophthoracee.*—M. A. Giard identifies Hmpusa Fre-
seniana Nowak. (Triplosporium Fresenii Thaxt.), parasitic on Aphis Mali,
with Neozygites Aphidis, hitherto placed among the Gregarinide. The
genus Basidiobolus of Eidam he regards as nothing but a phase of
development of a particular group of Entomophthoracew parasitic on
flies. The two kinds of spore of B. ranarum occur also in Entomo-
phthora Calliphore. The former is found on the excrement of frogs,
lizards, &c., which feed largely on Calliphora. It is probable that the
spores germinate in the digestive tube of the fly, and attain their full
development only in the excrement of the animal which devours it,
where it puts out hyphe and conids and a small number of hypnospores.

The following new species are described :—Entomophthora saccharina,
parasitic on the larva of Euchelia Jacobezx ; E. Plusiz, on the larva of
Plusia gamma; Metarhizium Chrysorrhee, on the larva of Liparis
Chrysorrhea ; M. ? Leptophyei, on a rare orthopter, Leptophyes punc-
tatissima.

Urophlyctis Kriegeana sp. n.{—Herr P. Magnus finds this new
species of Chytridiacee forming galls on Carum Carui. Hyphe
belonging to the mycele conjugate by means of a short canal, the
contents of one of the hyphe flowing through this canal into the other,
which then developes into a brown resting-cell, or more probably resting
zoosporange, with smooth wall. The central chamber of mature galls
contains a number of these resting-cells, attached to which are often to
be seen the membranes of the empty conjugating-cells.

Elzomyces, a new type of Fungi.{—Herr O. Kirchner has found,
in asample of oil of poppies, a remarkable fungus, to which he has given
the name Elzomyces olei. When completely immersed in the oil, the
somewhat elongated cells appear to multiply themselves only by a kind
of torulose sprouting, similar to that of Saccharomyces or Mucor ; but,
when more or less completely exposed to the air, the development is
totally different. The cells lose their linear connection with one another,
round themselves off, and unite into an irregularly outlined agglomera-
tion of cells. Of these cells the greater number gradually lose their
contents and perish, while a few increase in size, acquire a thicker wall
and denser granular contents, finally becoming spores of a somewhat
lemon-shaped form, the germination of which, however, was not followed
out. The author regards the formation of the “spores” as a kind of
conjugation, which may possibly establish the systematic position of
Elzomyces to be among the Zygomycetes, near the Ustilaginex.

Synthesis of Physcia parietina.§s—M. G. Bonnier sowed spores of
Physcia parietina among about 40 cells of Protococcus viridis. He was
thus able to observe the first differentiation of the filaments which
proceed from the spores, and their envelopment of the algal cells. He
could watch the formation of the pseudo-parenchyme, and the mode in

* CR. Soe. de Biol., Nov. 24, 1888. See Morot’s Journ. de Bot., iii. (1889) Rev.
Bibl, p. iii. + SB. Ges. Naturf. Freunde, 1888, pp. 100-4.

t Ber. Deutsch. Bot. Gesell., vi. (1888) Gen.-Vers.-Heft, pp. ci.-civ. (1 pl.).

§ Comptes Rendus cvyii. (1888) pp. 142-4.

562 SUMMARY OF CURRENT RESEARCHES RELATING TO

which the algal cells gradually develope into the gonids of the lichen.
All the phases of development, from the germination of the spores to
the formation of a thallus identical with that found in nature, were
studied in detail.

New development of Ephelis.* — Dr. M. C. Cooke and Mr. G.
Massee describe a new development of Ephelis which was discovered on
Panicum palmifolium. As in other cases of proved dimorphism, the
stylosporous form and the ascigerous form are still retained separately
under their respective genera; so in this case the authors describe the
new Ephelis under the name E. trinitensis ; and other specimens were
found on the same host, which carried the history forward much further.
Instead of the discoid cup-like receptacles exhibited by Ephelis, each of
them was transformed, or was in the course of a transformation, into a
basin-shaped capitulum of 1 to 14 mm. diameter, raised upon a peduncle
two or three times its length; the transformation being brought about
by the replacing of the concave surface of the cups by a convex one, and
the subsequent elevation of this surface on a stalk. In the authors’
opinion there is very little doubt that this fungus must be referred to
the genus Balansia, and they describe a new species under the name of
B. trinitensis. The difference between this species and Balansia
claviceps Speg. are then pointed out, and the paper concludes with some
remarks on the morphology of Ephelis.

Disease of Chestnut-trees.j —M. C. Roumeguére describes a disease
which has caused great ravages among the chestnut-trees in Aveyron,
Var, Dordogne, and Haute-Vienne. It is caused by the fungus Phyllo-
sticta maculiformis, and was described by Prof. Saccardo in 1881.
Phyllosticta always developes on the under side of the leaf, and forms
small groups of black peritheces ; these peritheces dehisce by a pore, and
at maturity emit cylindrical sporules which are distributed far and
wide by the wind, and germinate in the spring of the following year.
Phyllosticta is supposed to be one of the forms of the well-known Spheria
maculiformes.

Life-history of Macrosporium parasiticum.{—Mr. Kingo Miyabe
describes the life-history of Macrosporium parasiticum Thim., the
material being found on onion-plants in Bermuda.

The following is a recapitulation of the principal results obtained :—

1) The ascosporous stage of M. parasiticum is the common Pleospora
herbarum (Pers.) Rabenh. (2) M. parasiticum is identical with M.
Sarcinula Berk. (8) Pleospora herbarum is decidedly a facultative
parasite. (4) There are only two stages in the development-cycle of P.
herbarum, the ascosporous and the Sarcinula stage. (5) The presence of
pycnids in P. herbarwm is very doubtful, and they may have entirely
disappeared from its cycle of development. (6) No Alternaria-torm
belongs to P. herbarum. (7) The formation of the perithece is purely
non-sexual. (8) No Woronin’s hyphe or similar spiral processes are
found in the peritheces before the formation of asci and paraphyses.
The asci and paraphyses are produced from the same short chains of
parenchymatous cells, which are formed by elongation and division of
the pre-existing cellular groups of parenchymatous nature filled with

* Ann. of Bot., iii. (1889) pp. 33-9 (1 pl.). f Rev. Mycol., xi. (1889) pp. 34-5.
+ Ann. of Bot., iii. (1889) pp. 1-24 (2 pls.).

ZOOLOGY AND BOTANY, MIOROSCOPY, ETO. 563

highly refractive contents, and situated generally in a central portion of
the perithece.

American “Bitter-rot.’"*—According to M. F. Cavara, the fungus
which causes the vine-disease, known in America as “ bitter-rot,” is not
Coniothyrium diplodiella, but must be placed in the genus Melanconium,
where it may be distinguished as M. fuligineum. It is the only species
of the genus at present known which is parasitic on the fruit of a
dicotyledon.

Cladosporium herbarum.j—M. J. Costantin gives the details of
some researches on Cladosporium herbarum, and also on Alternaria tenuis.
He gives several reasons for thinking that there exists a relationship
between Cladosporium and Alternaria, and states that the primitive
opinion of Tulasne is confirmed, and that the polymorphism of
Cladosporium is even greater than that savant supposed.

M. E. Laurent { states that this fungus may present, in addition to
its normal form, either of the following :— (1) Penicillium cladosporioides
Fres., or (2) Dematium pullulans De Bary, or (3) the white “ levure”
of Pasteur, or (4) the Fumago-form. The author proposes also a reform
in the terminology applied to Hymenomycetes, to meet the progress
which has taken place recently.

Microscopic twining Fungus.§—Dr. R. Ludwig describes a minute
fungus parasitic on Bertya rotundifolia (Euphorbiacee) from Kangaroo
Island, South Australia. The leaves of the host are covered with tufts
of hairs, which are attacked by the fungus, the twining stems of which
completely surround and embrace the hairs, always turning to the left.
It is probably nearly allied to Fumago and Pleospora, and is apparently
genetically connected with moniliform toruloid chains of cells on the
upper side of the leaf, belonging to a fungus named by Saccardo
Heterobotrys paradoxa. The only mode of propagation described is by
non-sexual spores.

Heterospory of Gymnosporangium.||—Dr. P. Dietel makes the
interesting observation that several species of Gymnosporangium produce
two kinds of teleutospore. The ordinary thick-walled brownish form is
produced only in the outer part of the fructification ; these are only
slightly constricted at the line of junction of the merispores, which
remain closely connected with one another. The second kind of teleuto-
spore has a very thin colourless membrane, and consists of only two
merispores which separate very readily from one another owing to a
deep constriction at the line of meeting. They are imbedded in muci-
lage, and contain an orange-yellow cell-content. Although these thin-
walled teleutospores do not differ in morphological value from the thick-
walled ones, they appear biologically to represent the uredospores of
other Uredinew. They have been observed in Gymnosporangium clava-
rieeforme, juniperinum, Sabine, macropus, clavipes, globosum, and bi-
septatum.

Mildew of the Apple. /—The mildew of the apple-tree has been
attributed by different writers to various fungi, Phyllactinia suffulta,

* Ist. Bot. R. Univ. Pavia, 1888, 4 pp. See Bull. Soc. Bot. France, xxxvi. (1889)
Rey. Bibl., p. 20. + Journ. de Bot. (Morot), iii. (1889) pp. 1-3.

t Rev. Mycol., xi. (1889) pp. 105-6.

§ Ver. Naturfr. Greiz, Jan. 1889. See Bot. Centralbl., xxxvii. (1889) p. 339.

|| Hedwigia, xxviii. (1889) pp. 19-23, 99-103. q T.c., pp. 8-12.

564 SUMMARY OF CURRENT RESEAROHES RELATING TO

‘several species of Hrysiphe, and Podosphera Kunzei. Dr. P. Sorauer
finds the white tufts on the upper side of the leaf to consist of the
conidial form of a fungus closely allied to Sphzrotheca Castagnet, and
which he describes as f. Mali of that species. ‘The peritheces were not
found on the leaves themselves, but on the leaf-stalks or young branches.

Uredinex of Pinus Strobus.* —Herr H. Klebahn finds very great
injury inflicted on plantations of the Weymouth pine by two parasitic
fungi belonging to the Uredineew, Peridermium Strobi and P. Pini
corticola. Experiments were made to determine the teleuto- and uredo-
spore forms that are genetically connected with the ecidio-form which
attacks the pines, especially those found on various species of Ribes ;
and the author claims to have established the connection between
Peridermium Sirobi on Pinus Strobus, Lambertiana, and monticola, and
Cronartium ribicola on Ribes aureum, nigrum, rubrum, and sanguineum.
Aicidiospores of P. Strobi sown on leaves of Cynanchum Vincetoxicum
produced no result. The “spermogones” of P. Strobi are also described ;
the author is unable to assign any sexual function to the “ spermatia.”
He was not able definitely to determine the genetic connection between
Peridermium Pini corticola and Cronartium asclepiadeum, though he con-
siders it probable.

Coleopuccinia.t—M. N. Patouillard describes a new genus which
comes between Gymnosporangium and Uropyxis, from Yunnan, the
teleutospores of which germinate on Amelanchier. This parasite has
spores of the same form as those of a Puccinia ; they are composed of
two superposed cells, the lower being supported by a colourless stipe of
the same length as the cell. Hach of these spores is inclosed in a
cylindrical sheath which is closed both above and below, and is colour-
less and gelatinous. The author concludes by giving a diagnosis of this
new genus, to which he has given the name Coleopuccinia, on account of
the sheath, and to denote its affinity to Puccinia.

Tulasnella, Prototremella, and Pachysterigma.{—M. J. Costantin
states that Tulasne many years ago described a fungus haying the
external characters of Corticium incarnatum, but differing in the
basids bearing swollen sterigmata. Not attributing very much import-
ance to this, he made a variety pinicola. In 1888 the preceding was
described as a genus by three separate authors; these three genera are
Tulasnella Schroet., Prototremella Pat., and Pachysterigma Bref., Istv.,
and Olsen. Tulasnella being the oldest name, ought to be preserved.
It represents somewhat of a transition between the Hypochnacez and
Dacryomycetes, approaching the former in the disjointed hymenium and
aspect of Oorticium, and the latter in the swollen sterigmata.

Phosphorescence of Agaricus olearius.§—According to Sig. U.
Martelli, the phosphorescence of this fungus is not increased by a rise in
temperature, nor by immersion in oxygen; in carbonic acid it gradually
dies away, and disappears entirely at a temperature of 90°C. Every
separate particle of the lamella is endowed with luminous properties ;
for, if any point of a lamella is touched, all the other lamelle at once
become luminous on both sides. The author considers that the phos-

* Ber. Deutsch. Bot. Gesell., vi. (1888) Gen.-Vers.-Heft, pp. xlv.-lv.
+ Rey. Mycol., xi. (1889) pp. 35-6.

} Journ. de Bot. (Morot), iii. (1889) pp. 59-60.

§ Rev. Mycol., xi. (1889) pp. 97-9. Cf. this Journal, ante, p. 426.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 565

phorescence has nothing to do with the process of reproduction, and that
combustion is an effect rather than the cause of the phenomenon.

Phosphorescent Mushroom.*—Mr. G. F. Atkinson finds that the
hymenium and a portion of the hymenophore directly adjacent of
Agaricus (Clitocybe) illudens Schw. emit a phosphorescent light. Very
young plants were also phosphorescent, though not so bright as when
mature.

Poroptyche, a new genus of Polyporex.{—G. Ritter v. Beck gives
the following diagnosis of a new genus represented by Poroptyche
candida, found on dry calcareous soil, Fungus resupinato-expansus, in
margine definito et sursum accrescens, in tota superficie poriferus, subtus
mycelii ramis funiformibus solo indefinito sed arcte affixus. Pore in
margine primum foveate rotunde, mox magis concavate, lobis varie
accrescentibus tortuose et labyrinthiformes, sepe clause, serius
stroma poris numerosissimis irregulariter perforatum, et in superficie
poris apertis preeditum formantes. Hymenium poros induens. Basidia
clavata, in stipitibus brevibus sporas 4 ellipsoideas hyalinas fingentia.
Cystidia nulla,

Mycose on the Sporange of Mosses.{—M. Amann describes a fungus
which attacks the sporange of mosses and envelopes the young spores in
numerous ramifications, arresting their development, and depriving them
of chlorophyll, and finally agglomerating them into a compact mass
which is incapable of germination.

Protophyta.
a, Schizophycesze.

Peroniella, a New Genus of Schizophycese.§—Dr. C. Gobi finds,
attached to the gelatinous envelope of Hyalotheca mucosa, an organism
to which he gives the name Peroniella Hyalothece, and which he places
among the Chlorophycee near to Sciadium and Ophiocytium. It consists
of a single cell, at first ovoid or pear-shaped, but afterwards becoming
spherical, fixed to the gelatinous sheath of the desmid by an elongated
pedicel. The contents of the cell break up into seven or eight uni-
ciliated zoospores. The vegetative cell also becomes encysted, by simple
thickening of its cell-wall, and contraction of its protoplasm.

Stomatochytrium, a new genus of Endophytic Protococcacez.|—
Dr. D. D. Cunningham describes, under the name Stomatochytrium
Limnanthemi, an endophytic green protophyte found in the stomates of
the upper surface of the leaf of Limnanthemum indicum, resembling
Chlorochytrium Lemne in its mode of life. It produces zoospores
(zoogametes), which conjugate in the ordinary way, the zygosperms
coming to rest after a period of swarming; but no germination was
observed either of the zoospores or of the zygosperms. One point in
which the genus is stated to differ from Chlorochytrium is that the
zoospores are set free within the zoosporange. It is, like Chlorochytriwm,
not a true parasite, but an endophyte.

* Bot. Gazette, xiv. (1889) p. 19.

+ Verhandl. K. K. Zool.-Bot. Gesell. Wien, 1888, pp. 657-8 (3 figs.).
t Rev. Bryol., xvi. (1889) p. 13.

§ Scripta Botanica, i. (1887) 1 pl. See Bull. Soc. Bot. France, xxxvi, (1889)
Rey. Bibl., p. 6.

| Scient. Mem. by medical officers of the army of India, part iii, 1888, pp. 33-40.

566 SUMMARY OF CURRENT RESEARCHES RELATING TO

Tetraedron.*—Prof. A. Hansgirg revises his monograph of this
genus of Alga, enumerating now twenty-seven species, arranged under
the four subgenera Polyedrium, Closteridium, Pseudostaurastrum, and
Thamniastrum, the first of these again consisting of two sections,
EKupolyedrium and Cerasterias.

Movements of Diatoms and Oscillaria.t—According to the observa-
tions of Mr. W. A. Terry, the same species of diatom always occupies
the same position while inmotion. Thus Stauroneis acuta always travels
with the valves vertical, showing the broad hoop or band and the edges
of the valves, as also do several species of Pinnularia and Surtrella ;
while Stauroneis phenicenteron travels with the valves horizontal, showing
one uppermost, as also do several species of Pinnularia, Surirella, and all
the species of Pleurosigma. 'The maximum rate of speed of diatoms is
stated to be a distance of about their own length in two seconds.

The movements of Oscillaria cannot be explained, in the author’s
opinion, by movements of the protoplasm, inasmuch as this is inclosed
in a rigid sheath. The proper motion appears to be an onward spiral
movement forward and backward in the direction of the length of the
filament, showing a striking resemblance to the motion of diatoms, and
probably produced in a similar manner, The waving and nodding
movements are always caused by the elasticity of the filament springing
back to regain its normal position while working itself free from
obstructions.

Valve of Pleurosigma.{—Mr. T. F. Smith claims to have deter-
mined that the valve of Pleurosigma formosum consists of several layers
of structure; the same is also true of P. decorum, balticum, and angu-
latum, and probably of other species of the genus. He recognizes three
types of valve-structure in Pleurosigma, viz.:—(1) a valve composed of
two layers of square grating, as P. balticum ; (2) a valve with two
layers of grating, with secondary markings placed diagonally, as P.
formosum ; and (3) a valve with two layers of net-like structure, as P.
angulatum; and it is probable that all the species may be referred to one
or other of these types.

Fossil Marine Diatoms.§—Mr. C. H. Kain and Mr. H. A. Schultze
describe a remarkable fossil marine diatomaceous deposit from Atlantic
City, New Jersey, which includes also a few fresh-water forms. Several
new species are described, including possibly the type of a new genus.

Synedra pulchella Ktz., var. abnormis.||—Under this name Sig. L.
Macchiati describes a remarkable form of this pleomorphic diatom,
agreeing with the type-form in the presence of a “definite annular
pseudo-nodule” or “median circle,” but characterized by a singular
regular constriction near one end of the frond. ‘The author proposes a
rearrangement of the species included in the genus, depending on the
fineness of the striation, and would separate the varieties macrocephala
Grun. and naviculacea Grun. as distinct species.

* Hedwigia, xxviii. (1889) pp. 17-9. Cf. this Journal, 1888, p. 1013.
+ Amer. Micr. Journ., x. (1889) pp. 81-3.

¢ Journ. Quek. Micr. Club, iii. (1889) pp. 301-7 (1 pl.).

§ Bull. Torrey Bot. Club, xvi. (1889) pp. 71-6 (1 pl.).

|| Nuoy. Giorn. Bot. Ital., xxi. (1889) pp. 263-7 (2 figs.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 567

Classification of Cyanophycee.*—Dr. A. Hansgirg supplements his
scheme of classification of the Myxophycex (Cyanophycee) by a few
additional details, and adds descriptions of a new species Cyanoderma
(Myxoderma) rivulare.

Parasitism of Nostoc.t—In reference to the observations of Frank t{
on the power of plants to absorb free nitrogen from the atmosphere,
Prof. K. Prantl suggests that this may be the function of the colonies of
Nostoc or Anabeena so frequently found in cavities in the leaves of
Blasia, Anthoceros, Azolla, Gunnera, Cycas, &c., thus serving to help in
the nutrition of the host-plant. The same also may be the purpose of
the Schizophycee belonging to these genera which enter into the
composition of Collema and other large lichens.

B. Schizomycetes.

Morphology and Physiology of the Sulphur Bacteria.§—The first
volume of his work on Bacteria Dr. T. Winogradsky devotes to the
Sulphur-bacteria.

In a short introduction the author discusses the views of Ray
Lankester, Warming, Zopf, and Cohn, who have expressed opinions for
or against the pleomorphism of these organisms. After reviewing the
various sulphur-bacteria, he decides that all the forms are distinct
species, and are not pleomorphic organisms, and that all the forms
included by Lankester, Zopf, and Warming can be sharply separated
from one another.

Thus Cladothrixw dichotoma developes in quite a simple manner ; the
spirilla, zoogloew, &c., which Zopf has connected together are indepen-
dent organisms ; and this is the case with leptothrix and others. In con-
clusion, the author shows that the last support of the doctrine of
pleomorphism has been removed, and that Cohn’s classification of the
species was correct.

Prof. A. Hansgirg, || on the other hand, regards the sulphur-bacteria
described by Winogradsky as forms, developed under special con-
ditions, of already known. genera and species. At all events, as far
as the genera are concerned, he identifies Winogradsky’s Thiotria with
Borzi’s Ophryothrix, Thiosarcina with Sarcina, Thiopedia with Lampro-
pedia, and Thiospirillum with Spirillum. Thiopolycoccus, Thiocapsa, and
Thiocystis must also probably be sunk in corresponding genera pre-
viously described.

Bacteria which produce Sulphuretted Hydrogen.§—Dr. Holschew-
nikoff, in a somewhat diffuse paper on the formation of HS by bacteria,
gives the result of a few experiments made with two bacteria, called
Proteus sulphureus and Bacterium sulphureum.

The former appears to closely resemble Proteus vulgaris Hauser,
even if it be not identical with it. The latter, which was isolated from
some reservoir mud, consists of rodlets with rounded ends, and with
a length of 1:6-2°4 yw, and breadth of 0°5 yp. In the former aerobic

* Notarisia, iv. (1889) pp. 656-8. Cf. this Journal, ante, p. 102.

+ Hedwigia, xxviii. (1889) pp. 135-6. t Cf. this Journal, ante, p. 412.

§ ‘ Beitrage zur Morphologie und Physiologie der Bacterien,’ 8vo, vol, i., Leipzig,
1888, vi. and 120 pp., 4 pls. Cf. this Journal, 1887, p. 1007.

|| Bot. Centralbl., xxxvii. (1889) pp. 413-4,

4 Ann. de Micrographie, ii. (1889) pp. 257-74.

568 SUMMARY OF CURRENT RESEARCHES RELATING TO

characters predominated, in the latter anaerobic. The sulphuretted
hydrogen was detected by means of slips of filter-paper soaked in a
solution of alkaline acetate of lead.

The first series of experiments were made with eggs; the white and
yolk being used, both raw and cooked. H,S was produced under all
circumstances, but in varying quantities. Besides eggs, blood-serum
and peptonized bouillon were employed, also with production of H,S.
In milk and sterilized casein no gas was developed. Hence the author
infers that the cultivation medium seems to exert the decisive action,
and not the presence or absence of oxygen.

Experiments with sterilized urine showed that B. sulphureum pro-
duced H,S, but Proteus sulphureus failed to do so.

The addition of 0-5-3 per cent. of grape and milk sugars to pep-
tonized broth prevented the formation of H,S; hence the same microbe
can effect a putrefaction which, according to the nature of the cultivation-
medium, is with or without odour.

Experiments with certain sulphur salts, as sulphates and snlpho-
cyanates, failed, but positive results were obtained from a 0°5 per cent.
solution of hyposulphate of soda in the presence of air, with Proteus
sulphureus ; while B. sulphureum could only do so in the absence of air.

The last series of experiments were devoted to testing the assertion
of Duclaux that the so-called aerobic fermentations are truly anaerobic.
Three flasks of bouillon were taken; in one the surface was covered
with oil, in the second the neck was merely plugged with cotton-wool,
in the third arrangements were made to aerate the bouillon during the
experiment. From the results of these experiments the author con-
cludes that aerobiosis and anaerobiosis do not count for everything, but
that the ultimate causes are to be sought for in the specific qualities of
protoplasm.

Bacillus of Leprosy.*—Dr. C. Q. Jackson finds that the micro-
scopical character and general morphology of Bacillus lepre greatly
resemble B. tuberculosis, but a point of difference is to be noted in that
the bacilli of tubercle are not motile, while some of those of leprosy are.
Inoculation with B. tuberculosis readily produces a characteristic
definitely tubercular lesion, but the Bacillus of leprosy is difficult to
inoculate in the lower animals, and in Man appears to require a certain
predisposing condition. B. lepre stains more easily than B. tuberculosis,
though the same staining processes and reactions are applicable to both.

Vaccinal Properties of Microbes. | —M. A. Chauveau has, since
1884, been engaged in cultivating successive generations of Bacillus
anthracis under a pressure of about nine atmospheres. He has thus
succeeded in diminishing considerably its virulence, and in making it
harmless to the sheep. ‘Taking two infusions, one of which (A) was
rather less powerful than the other (B), M. Chauveau has found that
the first generation of A, after cultivation in compressed oxygen, was
completely devoid of any pathogenic power; and successive generations,
cultivated under normal conditions, gave also innocuous microbes, B
had to be submitted for two generations to the increased pressure of
oxygen before it lost its pathogenic powers.

In neither case, however, was there any change in the form of the

* Proc. Amer. Soc. Mier., x. (1888) pp. 119-27.
+ Comptes Rendus, cviii. (1889) pp. 319-24, 379-85.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 569

Bacillus or in its vegetative power, nor was there any loss of vaccinal
effect. Still more remarkable, however, is the result of cultivating these
innocuous microbes in cultivations only feebly nutrient or under a low
pressure, for these recover their toxic powers on small animals; it
remains to be seen whether they cannot be cultivated so as to injure
sheep and oxen.

Hueppe’s Bacteriology.*—Dr. F. Hueppe has recently published
the fourth edition of his work on the methods of examining Bacteria.
The present edition has been revised and improved throughout, and
also much enlarged. It contains 434 pages, 2 coloured plates, and 68
wood engravings. It is divided into two parts, which respectively deal
with the microscopical and experimental technique of the subject. It
seems to contain all the necessary information brought up to date.

Tuberculous Infection of the Fowl-embryo.t—Prof. A. Mafucci
gives the following account of an.experiment made on hens’ eggs by
inoculating them with fowl-tubercle.

A cultivation from fowl-tubercle was first made on calf’s blood-
serum, and afterwards mixed with sterilized meat-broth. On June 28,
1888, a hen and a guinea-pig were inoculated for control purposes, and
at the same time eighteen eggs, which were thereupon put under a
brooding hen for incubation.

The guinea-pig died of tuberculosis in 40 days, and the hen in two
and a half months. On July 17 eight chicks came out; of the rest of the
eges some had not been fertilized, and the others had become rotten.
One showed a dead embryo, but this gave no evidence of tubercle or
bacilli. The eight chicks were all small and delicate but active, except
one, which died 36 hours after hatching out. Careful examination failed
to reveal tubercle bacilli, though some spherical bodies were found
among the liver-cells. The second chick died 20 days after hatching,
and was much emaciated. Microscopical examination showed tubercle
bacilli in nodules in the liver. The third chick died 32 days after
hatching, presenting similar appearances to the last; the fourth chick
in 40 days, similar to last; the fifth in 42 days, the most emaciated of
the series; no naked-eye appearances, but microscopical tubercles in
liver, lungs, kidneys, stomach, and intestine. The sixth died in 47 days;
tubercles in liver, lungs, and lymphatic elements. The seventh died
78 days after hatching ; tubercles evident to naked eye in lungs and
liver. The eighth died four and a half months after hatching; was
emaciated and poorly developed in comparison to healthy chicks born
at the same time. ‘There were malformations of the skeleton in the
sternum, vertebral column, pelvis, beading of the costal cartilage, in fact
all the signs of rickets. The liver and lungs showed tubercles, many
of which were caseous, and of course bacilli were found on microscopical
examination.

The only inference the author permits himself to draw from the
foregoing very interesting experiments is that the tubercle bacillus of
fowls, having penetrated the embryo, is not destroyed, but remains viable,
and while not absolutely preventing the development of the embryo,
produces its serious effects at a later stage. But in order to obtain
correct information as to when and how the morbid process is set up,

* 8vo, Wiesbaden, 1889.
+ Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) pp. 237-41.

570 SUMMARY OF CURRENT RESEARCHES RELATING TO

the eggs must be opened from the first day of incubation up to the time
of the hatching of the chicks, and the albumen as well as the organs and
blood of the embryo examined. In this way the phases in the develop-
ment of the tubercle bacillus and the time of its penetration into the
embryonic tissue may be ascertained.

The author further expresses the opinion that the virus infects the
embryo through the area vasculosa, which picks it up and passes it on
to the liver, for this is the first point at which its effects are perceived.
The lung affection is subsequent to that of the liver, for it probably
does not take place through the amniotic fluid swallowed by the embryos,
since in these the digestive tract is not affected in the same way as it is
in the adult.

Bacillus murisepticus pleomorphus, a new pathogenic Schizo-
mycete.*—Dr. J. Karlinski has isolated from the pus of an abscess on
the lower part of a thigh, and also from that found in a case of puerperal
septicemia, a bacterium which has certain resemblances to Hauser’s
Proteus. It appears under all the various shapes characteristic of
Schizomycetes generally, ranging from cocci to spirilla. Its most con-
stant form is a rodlet about 24 times as long as broad, and these are
frequently seen in pairs. The longer forms are motile, and the shorter
possess a tendency to form zoogloea masses. The bacillus was cultivated
on the usual media, and seems to thrive better on gelatin, which it
liquefies, than on agar.

White mice inoculated with pure cultivations rapidly die, the organ
most affected being the spleen, which is much enlarged and almost
diffluent. White rats, guinea-pigs, rabbits, and dogs were also inocu-
lated, but showed themselves less sensitive, though guinea-pigs and
rabbits died if injected directly in a blood-vessel. Frogs injected in the
dorsal lymph-sac died in 2-4 days. With regard to these last animals,
the author notes that he had found the bacilli in their white corpuscles,
but never, even in the splenic blood, in the warm-blooded animals.

Variations of Vibrio Proteus.t—Dr. G. Firtsch gives an account of
some variations of Vibrio Proteus (Finkler-Prior’s comma bacillus)
which appeared in a cultivation that was certainly pure originally.
The first variation was remarked in a plate cultivation 307 days old,
and the new vibrio was distinguished from the true V. Proteus by the
colonies having a more wavy contour, being of a yellowish colour, and
being beset with small prominences. In two or three days’ time the new
vibrios were found to be massed together in the centre of the colonies.
These differences were seen not only in 10 per cent. meat-pepton-gelatin,
but in other media, in tube cultivations; and on microscopical examina-
tion, other distinctions could also be observed, but these were not so
marked. The behaviour of this vibrio on nutrient gelatin may therefore
be regarded as being the chief criterion of this variation, which was also
found, together with the real Vibrio Proteus, in two cultivations a year
old.

Two other variations were obtained from the original cultivations at
still later periods. ‘They are called vibrios 2 and 3, and show some
slight differences from each other and from the original, the most notice-

* Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) pp. 193-207 (1 pl).
+ Arch. f. Hygiene, viii. (1888) p. 369.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 571

able of these being that vibrio 3 varies from 5-150 yw long and from
0-8-1 p» thick.

The inference drawn by the author is that every kind of bacterium
shows, for the same conditions and for the same media, the same forms ;
but for different external conditions and for different media many kinds
of bacteria alter their course of development and change their shape and
appearance. Hence it is incorrect to say that only one of these forms
is the true or normal condition, and that all others are pathological.

Flagella of the Cholera Bacilli.*—It is a legitimate inference, says
Dr. R. Neuhauss, from the fact of their lively movements, that cholera
bacilli are possessed of flagella. After failing in various ways to demon-
strate this appendage, the author hit upon the following method, which
gave positive results. Cultivations were obtained in meat broth of
bacilli, which in four weeks showed, instead of the tiny comma bacilli,
long spirilla and large thick bacilli. Most of these had lost their
motility, but a few specimens were still capable of movement. Cover-
glass preparations, stained black by means of Campeachy wood extract
and neutral chromate of soda, as well as unstained cover-glass prepara-
tions, failed to show the flagellum; nor by means of the Microscope
could any such appendage be observed when the bacilli were mounted
unstained in water, and pressed between the slide and cover-slip ; but by
photographing a preparation put up in this last-mentioned way, a nega-
tive was produced which showed a delicate spiral flagellum attached to a
short much curved bacillus. By repeatedly taking the same field, and
focusing for different levels, another flagellated bacillus was photo-
graphed. This result the author considers a great photographic triumph.
Subsequent examination showed that the cultivation employed had
remained quite pure.

Glischrobacterium.t—Dr. P. Malerba and Dr. G. Sanna-Salaris
have isolated from the urine of a female, aged fifty, a bacterium which
they believe to be the cause of a viscid stringy condition of this fluid.
They also mention another case of glischruria, from which the same
organism has been isolated. Besides the viscidity, this urine is remark-
able for a considerable acidity, which lasts for 40-50 days at ordinary
temperatures. It contains a few oxalates, is precipitated by tannic acid,
and then loses its viscosity.

The micro-organism to which this viscid condition is ascribed is a
coccus (long. diam. 1°14—0-57 »; trans. diam. 0°41»). During its
cultivation certain morphological differences were observed, and these
were found to be due to differences of media, age, and temperature.
Thus, in fresh non-peptonized bouillon the microbe is a bacillus endowed
with a slight rotary movement; it may or may not be constricted in the
middle, and may be arranged in pairs, or in chains. In old cultures the
chains are superseded by a mass of bacteria, and long chains are rarely
seen, except between 21° and 27°.

It stains well with fuchsin and methylen-blue.

Glischrobacterium grows on a large number of nutritive media: the
colonies are spherical, with depressed centres and somewhat crenated
margins. Occasionally they present an appearance like concentric rings
traversed by lines radiating from centre to periphery. If the colonies

* Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) pp. 81-4.
+ Arch. Ital. Biol., x. (1888) pp. 358-71 (1 pl.).

572 SUMMARY OF CURRENT RESEARCHES RELATING TO

grow deep, they are usually ellipsoidal. In the course of a few days
the deep colonies are surrounded by bubbles of gas (hydrogen).

Glischrobacterium does not liquefy gelatin, and, although it grows
best in the presence of oxygen, is capable of anaerobic development.
It grows well on agar, bouillon, milk, potato, serum, and egg-yolk, as.
well as on gelatin. In human saliva, either fresh, mixed, or sterilized,
it thrives wonderfully. Human urine inoculated with some of the
original urine, or with a pure cultivation, becomes viscid and stringy in
8-10 hours at 87° C., but experiments with dogs’ urine sometimes failed.

The morphological characters of this bacterium are not affected by
the chemical reaction of the nutrient media or by light, but are con-
siderably affected by temperature. Thus, it grows best at 37° C., but
not above 41°, or below 5° C. It is extremely sensitive to desiccation.

In experiments on animals the authors found that this bacterium,
when injected into the pleural or peritoneal sacs (guinea-pigs, rabbits)
is not harmful; that it does not multiply in the stomach or bladder
(dogs); that under the skin (guinea-pigs, rabbits, and dogs) it is emi-
nently pyogenic; that injected directly into the blood (dogs) it pro-
duces slight albuminuria, with structural alteration of the kidney, and
after two or three days causes the urine to become stringy ; and that,
as a rule, the Glischrobacteriwm dies between the second and fourth
days in the blood and in the organs, except in the kidney of the dog,
where it lives for a time as yet undetermined.

Mucous Disease of Hyacinths.*—Dr. A. Heinz has found that
hyacinths are affected by a wasting disease, attended with the production
of a foul-smelling mucus. The flowering parts are specially attacked,
but no part is exempt. Microscopical examination showed that the
mucus and the tissues were full of a bacterium, which is a mobile rod,
invariabiy single, with rounded ends, 4-6 » long and about 1 thick.
They propagate by direct fission, and stain well with all the usual dyes.

The bacillus was easily cultivated pure on gelatin, agar, and potato,
and healthy plants inoculated from these cultivations showed evidences
of disease, most marked about the inoculation spot, in twenty-four hours.
Hence the author concludes that this microbe is the actual cause of the
disorder, and the name given to it is Bacillus Hyacinthi septicus. It
does not liquefy gelatin. Superficial colonies on plates are circular,
about 2mm. in diameter, bluish-white in colour, with a somewhat darker
centre. Those lying deeper are oval, and of a dull yellowish-white.
The cultivation differences on gelatin and agar are not noteworthy.
On potato there forms in thirty-six hours a yellow slimy layer, and in a
few days the cultivations give off a strongly offensive smell.

Other authors, notably Sorauer and Wakker, have described wasting
diseases of hyacinths, attended with the production of mucus. These
also were caused by bacteria, but Dr. Heinz considers that the disease
observed by him is distinct from the yellow and white mucous degenera-
tion of Wakker and Sorauer.

Bacteriology of Snow.t{—Dr. F. G. Ianovsky, who has examined a
February snow, collected immediately and from one to three days after
its fall, finds:—(1) That even when collected during its fall, snow is
invariably found to contain living bacteria in considerable numbers,

* Centralbl. f. Bakteriol. u. Parasitenk , vy. (1889) pp. 535-9.
+ Vratch, 1888, p. 727. Cf. The Microscope, ix. (1889) pp. 115-7.

ZOOLOGY AND BOTANY, MICROSOOPY, ETO. 573

varying from 34-463 per cubic centimeter of snow-water. (2) That
their number does not decrease from exposure of snow to low tempera-
tures (— 16°C.) for several days. (3) That the three following species
of microbes are constantly met with in great numbers :—(a) a large
diplococcus composed of ovoid cocci, endowed with energetic motion,
and characterized by its rapidly liquefying gelatin. In test-tube
cultures greenish colonies form on the third day along the needle track,
and assume the shape of a funnel-like sac, with a whitish flocculent
deposit ; while by the fifth the whole medium becomes liquefied, and the
precipitate sinks to the bottom. On agar, a pale greyish streak is
formed at the site of inoculation ; on potato, a fairly thick white film.
(b) Small-sized cocci, often arranged two and two, energetically mobile,
and slowly growing on gelatin without liquefying the medium, the
growth proceeding slowly along the track of the needle in the shape
of a narrow strip consisting of non-coalescing points of a yellow colour,
while on the surface the colony is seen as a greyish-white circular
slightly prominent patch, with somewhat fringed edges. On agar the
coccus forms a white streak with sinuous edges; on potato a grey film
with a brownish tint. (c) Very large cocci, liquefying gelatin as late as
three weeks after inoculation, and growing along the needle track in the
form of a sharply defined streak of a pink colour, with a slightly elevated
pink circular patch or cap on the surface. On agar the microbe forms a
freely spreading white film with a rosy tint; on potato a thick tallow-
like pink coat, with sharply defined fringed contours. (4) That the
first two species are also met with commonly in the water of the river
Dnieper, while the pink coccus seems to occur only in snow. (5) That,
generally speaking, the microbes which liquefy gelatin are met with in
greater variety and in far greater numbers in falling or recently fallen
snow than in snow which has been on the ground for some time. This,
in fact, very often contains such bacteria as do not liquefy gelatin.
(6) That the bacteria of snow originate partly in aqueous vapours which
are transformed into snow, partly and chiefly in the air—that is, they
are carried away by the snow-flakes in their passage through the
atmosphere,

1889. pia 4

574 SUMMARY OF CURRENT RESEARCHES RELATING TO

MICROSCOPY.
a Instruments, Accessories, &c.*

(6) Miscellaneous.

“The Compound Microscope invented by Galileo.” {— A very
interesting paper has been published by Prof. G. Govi, Hon. F.R.M.S.,
the eminent Italian physicist, in which he claims that Galileo was the
inventor of the Compound Microscope.

It should be borne in mind at the outset in considering Prof. Govi’s
paper that, as stated by him in a letter to the French Academy of
Sciences,t he understands by “ simple Microscope” an instrument “ con-
sisting of a single lens or mirror,” and by ‘‘ compound Microscope” one
“consisting of several lenses or a suitable combination of lenses and
mirrors.”

The following is a translation of Prof. Govi’s paper:—

In a pamphlet published in 1881,(1) treating of the invention of the
binocular telescope (attributed to D. Chorez, a French spectacle-maker),
I thought it right to recall that Chorez himself, in 1625, used the
Dutch telescope (with the convex objective and the concave ocular) as
a Microscope, (2) and stated that with a similar Microscope—

“Un ciron apparoist aussi gros qu’un poids. Tellement qu’on
discerne sa teste et ses pieds, et son poil, chose qui sembloit fabuleuse
a plusieurs, iusqu’a ce quils Pont veué avec admiration.” (“A mite
appeared as large as a pea; so that one can distinguish its head, its
feet, and its hair—a thing which seemed incredible to many, until they
witnessed it with admiration.”)

To this quotation I added—

“This transformation of the telescope into a Microscope (or as
opticians in our own day would say, into a Briicke lens) was not an
invention of the French optician. Galileo had accomplished it in the
year 1610, and had announccd it to the learned by one of his pupils,
John Wodderborn, a Scotchman, in a work which the latter had just
published against the mad ‘ Peregrinazione’ of Horky.(3) Here are the
exact words of Wodderborn (page 7) :—

‘Ego nunc admirabilis huius perspicilli perfectiones explanare nd
conabor: sensus ipse iudex est integerrimus circa obiectum proprium.
Quid quod eminus mille passus et ultra cum neque viuere iudicares
obiectum, adhibito perspicillo, statim certo cognoscas, esse hune
Socratem Sophronici filium venientem, sed tempus nos docebit et
quotidiane nouarum rerum detectiones qua egregie perspicillum suo
fungatur munere, nam in hoc tota omnis instrumenti sita est pul-
chritudo.

‘ Audiueram, paucis ante diebus authorem ipsum Excellentissimo

* This subdivision contains (1) Stands; (2) Eye-pieces and Objectives; (3) Illu-
minating and other Apparatus; (4) Photomicrography; (5) Microscopical Optics
and Manipulation ; (6) Miscellaneous.

+ ‘Il microscopio composto inventato da Galileo. Memoria di Gilberto Goyi.’
33 pp., 4to, Napoli, 1888. (Extract from vol, ii. series 2 of Atti R. Accad. Sci. Fis.
Nat. Napoli. Cf. also Comptes Rendus, cvii. (1888) pp. 551-2; Scientitic News, ii.
(1888) pp. 431-2; and this Journal, 1888, pp. 1067-8, and ante, p. 163—The num-
bers in brackets refer to the notes collected in the Appendix.

t~ Comptes Rendus, evii. (1888) pp. 551-2.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 575

D. Cremonino purpurato philosopho varia narrante scitu dignissima et
inter cetera quomodo ille minimorum animantium organu motus, et
sensus ex perspicillo ad ynguem distinguat; in particulari autem de
quodam insecto quod utrumque habet oculum membrana crassiuscula
vestitum, que tamen septe foraminibus ad instar larve ferres militis
cataphracti terebrata, viam prebet speciebus visibilium. En tibi (so
says Wodderborn to Horky) nouum argumentum, quod perspicillum
per concentrationem radiorum multiplicet obiectu; sed audi prius quid
tibi dicturus sum: in ceteris animalibus eiusdem magnitudinis, vel
minoris, quorum etiam aliqua splendidiores habent oculos, gemini tantum
apparent cum suis superciliis aliisque partilus annexis.’

““T have wished to quote this passage of Wodderborn textually, so
that the honour of having been the first to obtain from the Dutch tele-
scope a compound Microscope should remain with Galileo, which he
later called ‘ Occhialino, and that the glory of having reduced the
Kepplerian telescope to a Microscope (in 1621) should rest with Drebbel.
The apologists of the Tuscan philosopher, by attributing to him the
invention of the Microscope without specifying with what Microscope
they were dealing, defrauded Drebbel of a merit which really belongs
to him, but the defenders of Drebbel would act unjustly in depriving
Galileo of a discovery which incontestably was his.”

I turn now to Wodderborn’s account, published in 1610 (the date of
the dedication to Henry Wotton, English Ambassador at Venice, is
October 16th, 1610), which reads thus :—

“ T will not now attempt to explain all the perfections of this won-
derful occhiale, our sense alone is a safe judge of the things which
concern it. But what more can I say of it, than that by pointing a
glass to an object more than a thousand paces off, which does not even
seem alive, you immediately recognize it to be Socrates, son of
Sophronicus, who is approaching! But time and the daily discoveries
of new things will teach us how admirably the glass does its work, for
in that alone lies all the beauty of that instrument.

“T heard a few days back the author himself (Galileo) narrate to
the Most Excellent Signor Cremonius various things most desirable to
be known, and amongst others, in what manner he perfectly distinguishes
with his telescope the organs of motion and of the senses in the smaller
animals ; and especially in a certain insect which has each eye covered
by a rather thick membrane, which, however, perforated with seven
holes, like the visor of a warrior, allows it sight. Here hast thou a
new proof that the glass concentrating its rays enlarges the object; but
mind what I am about to tell thee, viz. in the other animals of the same
size and even smaller, some of which have nevertheless brighter eyes,
these appear only double with their eyebrows and the other adjacent

arts.”

E These last words of Wodderborn’s were directed to confute the
accusation of those who attributed to a fault in the telescope all that
was unknown to them before, and that was being discovered by the use
of it; being unwilling to admit the mountainous surface of the moon,
the satellites of Jupiter, and the new stars of the Milky Way, or any
other new discovery made by Galileo; because, said these people, the
ancients, and especially Aristotle, make no mention of them. (4)

After reading this document it is impossible to refuse Galileo the
credit of the invention of a compound Microscope in 1610, and the

y dale tay

576 SUMMARY OF CURRENT RESEARCHES RELATING TO

application of it to examine some very minute animals; and if he him-
self neither then nor for many years after made any mention of it
publicly, this cannot take away from him or diminish the merit of the
invention.

It is not to be believed however, that Galileo after these first experi-
ments quite forgot the Microscope, for in preparing the Saggiatore
between the end of 1619 (5) and the middle of October 1622 (6) he
spoke thus to Lotario Sarsi Segensano (anagram of Oratio Grassi Salo-
nense) (7) :—

“J might tell Sarsi something new if anything new could be told
him. Let him take any substance whatever, be it stone, or wood, or
metal, and holding it in the sun, examine it attentively, and he will see
all the colours distributed in the most minute particles, and if he will
make use of a telescope arranged so that one can see very near objects,
he will see far more distinctly what I say.”

It will not therefore be surprising if in 1624 (according to some
letters from Rome, written by Girolamo Aleandro to the famous M. de
Peiresc (8) ) two Microscopes of Kuffler, or rather Drebbel, having been
sent to the Cardinal of §. Susanna, (9) who at first did not how to use
them, they were shown to Galileo, who was then in Rome, and he as
soon as he saw them explained their use, as Aleandro writes to Peiresc
on the 24th May, adding, “ Galileo told me that he had invented an
Occhiale which magnifies things as much as fifty thousand times, so
that one sees a fly as large as a hen.”

This assertion of Galileo that he had invented a telescope which
magnified 50,000 times, so that a fly appears as big as a hen, must
without doubt be referred to the year 1610, and from the measure given
of the amplification by the solidity or volume the linear amplification
(as it is usually expressed now) would have been equal to something
less than the cubic root of 50,000, that is, about 36, and that is pretty
fairly the relative size of a fly and a hen.

Aleandro’s letter of May 24th (1624) does not state at what time
Galileo saw the telescope and explained the use of it, but another letter
of Faber’s to Cesi, amongst the autograph letters in the possession of
D. B. Boncompagni, (10) says (11th May) :—

“T was yesterday evening at the house of our Signor Galileo, who
lives near the Madalena; he gave the Cardinal di Zoller a magnificent
eyeglass (11) for the Duke of Bavaria. I saw a fly which Signor Galileo
himself showed me; I was astounded, and told Signor Galileo that
he was another creator, in that he shows things that until now we did
not know had been created.” j

So that even on the 10th May, 1624, Galileo had not only seen the
telescope of Drebbel and explained the use of it, but had made one
himself and sent it to the Duke of Bavaria.

We lack documents to show how this Microscope of Galileo was
made, that is, whether it had two convergent lenses like those of
Drebbel. A letter of Peiresc of the 3rd March, 1624, says that “the
effect of the glass is to show the object upside down... and so
that the real natural motion of the animalcule, which, for example, goes
from east to west, seems to go contrariwise, that is, from west to east”) ,
or whether it was not rather composed of a convex and a concave lens,
like that made earlier by him, and used in 1610, and then almost for-
gotten for fourteen years.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. ay id

It is, however, very probable that this last was the one in question,
for Peirese, answering Aleandro on the Ist July, 1624, wrote :—

“ But the occhiale mentioned by Signor Galileo, which makes flies
like hens, is of his own invention, of which he made also a copy for
Archduke Albert of pious memory, which used to be placed on the
ground, where a fly would be seen the size of a hen, and the instrument
was of no greater height than an ordinary dining-room table.”

Which description answers far better to a Dutch telescope used as a
Microscope in the same way exactly as Galileo had used it, rather than
to a Microscope with two convex lenses. (12)

One cannot find any further particulars concerning Galileo’s
“occhialini” (so he had christened them in the year 1624), either in
Bartholomew Imperiali’s letter of September 5th, 1624, in which he
thanks Galileo for having given him one in every way perfect, or in that
of Galileo to Cesi of September 23rd, 1624, accompanying the gift of an
“ occhialino,’ or in Federico Cesi’s answer of October 26th, or in a
letter of Bartholomeo Balbi to Galileo of October 25th, 1624, which
speaks of the longing with which Balbi is awaiting “the little occhiale
of the new invention,” or in that of Galileo to Cesar Marsili of Decem-
ber 17th in the same year, in which Galileo says to the learned
Bolognese, “that he would have sent him an occhialino to see close the
smallest things, but the instrument-maker, who is making the tube, has
not yet finished it.” (13) This, however, is how Galileo speaks of it in
his letter to Federico Cesi written from Florence on September 28rd,
1624, more than three months after his departure from Rome :—

“IT send your Excellency an occhialino, by which to see close the
smallest things, which I hope may give you no small pleasure and
entertainment, as it does to me. I have been long in sending it, because
I could not perfect it before, having experienced some difficulty in find-
ing the way of cutting the glasses perfectly. The object must be placed
on the movable circle which is at the base, and moved to see it all; for
that which one sees at one look is but a small part. And because
the distance between the lens and the object must be most exact, in
looking at objects which have relief one must be able to move the
glass nearer or further, according as one is looking at this or that part ;
therefore the little tube is made movable on its stand or guide, as we
may wish to callit. It must also be used in very bright clear weather,
or even in the sun itself, remembering that the object must be sufficiently
illuminated. I have contemplated very many animals with infinite
admiration, amongst which the flea is most horrible, the gnat and the
moth are most beautiful; and it was with great satisfaction that I have
seen how flies and other little animals manage to walk sticking to the
glass and even feet upwards. But your Excellency will have the oppor-
tunity of observing thousands and thousands of other details of the most
curious kind, of which I beg you to give me account. In fact, one may
contemplate endlessly the greatness of nature, and how subtilely she
works, and with what unspeakable diligence.—P.S. The little tube
is in two pieces, and you may lengthen it or shorten it at pleasure.”

It would be very strange, knowing Galileo’s character, that, in
1624, and after the attacks made on him for having perhaps a little too
much allowed the Dutch telescope to be considered his invention,
he should have been induced to imitate Drebbel’s glass with the two
convex lenses, and have wished to make them pass as his own invention,

578 SUMMARY OF CURRENT RESEARCHES RELATING TO

whilst he had always used and continued to use to the end of his days,
telescopes with a convex and a concave lens without showing that he
had read or in the least appreciated the proposal made by Keppler, ever
since 1611, to use two convex glasses in order to have telescopes with a
large field and more powerful and convenient.

In any case it is impossible to form a decided opinion on such a
matter, the data failing, but the very fact, that from 1624 onwards,
Galileo thought no more of the occhialino (probably because he found
it less powerful and less useful than the occhiale of Drebbel), as he had
not occupied himself with it or had scarcely remembered it from the
year 1610 to 1624, seems sufficient to show that the occhialino, like the
Microscope of 1610, was a small Dutch telescope with two lenses, one
convex and one concave, and not a reduced Kepplerian telescope like
that invented by Drebbel in 1621.

The name of Microscope, like that of telescope, originated with the
Academy of the Lincei, and it was Giovanni Faber who invented it, as
shown by a letter of his to Cesi, written April 13th, 1625, and which
is amongst the Lincei letters in the possession of D. B. Boncompagni.
Here is the passage in Faber’s letter :—

*T only wish to say this more to your Excellency, that is, that you
will glance only at what I have written concerning the new inventions
of Sig. Galileo; if I have not put in everything, or if anything ought
to be left unsaid, do as best you think. As I also mention his new
occhiale to look at smali things and call it Microscope, let your Ex-
cellency see if you would like to add that, as the Lyceum gave to the
first the name of telescope, so they have wished to give a convenient
name to this also, and rightly so because they are the first in Rome
who had one. As soon as Sig. Rikio’s epigram is finished, it may be
printed the next day; in the meanwhile I will get on with the rest.
I humbly reverence your Excellency—From Rome, April 13th, 1625.
Your Excellency’s most humble servant, Giovanni Faser (Lynceo).”

Faber himself, in the ‘Rerum Medicarum Nove Hispanie Thesaurus,’
of Hernandez, (14) which was being printed at the expense and by the
care of the Lyceum, and came out in a few imperfect copies in 1630,
reappearing in 1649, and definitely in 1651, speaking of the occhiale by
which to see minute objects (p. 473), wrote thus :—

“Vidimus et ad miraculum usque obstupuimus ante paucolos dies
(15) domi mew per Tubum opticum mire perspicuitatis artificiosissime
elaboratum 4 duobus Germanis huius artificibus fabrisq. nobis allatum
donatumque; quem a Telescopij imitatione et rerum minutarum con-
spectu Microscopium nominare libuit.”

And a little further on (p. 474), after having spoken of the Can-
nocchiale, which had received the name of Telescope from the President
of the Lyceum, Frederic Cesi, he continues :—

““Ab hoc nobis alterum Microscopium appellare visum fuit...
quod quidem a Galileo etiam anno proxime elapso in urbem allatum,
nunquam tamen ita diligenter elaborari ab ullis artificum manibus vel
ipsius vel collegarum jussu potuit quam ab istis Germanis, qui sedulam
in hoe operam preestitere, nec pauca huiusmodi Microscopia que urbem
totam in admirationem pertraxerunt, elaborata nobis exhibuerunt.”

The preceding quotation was a part of that ‘Scritto delle noue
invenzioni del Sig. Galileo’ which Faber was sending to Cesi, that he
might look it through with his letter of April 13th, 1625, above quoted.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 579

This ‘Scritto ’ is now in the possession of the Accademia dei Lincei, in a
large manuscript volume entitled, ‘318 Varia principis Casii Lynceo-
rum Academie, 985,’ where it is found on p, 372 recto, and was printed
by Faber, with slight variations, in the book already quoted of ‘ Tessoro
Messicano.’

The Abbé Rezzi, in a work of his on the invention of the Microscope,
(16) thought that he might conclude from the passage of Wodderborn,
reproduced above, that Galileo did not invent the compound Microscope,
but gave a convenient form to the simple Microscope, and in this way as
good as invented it, for the Latin word used by Wodderborn, perspicil-
lum, ‘signified at that time, it is clear (Rezzi says), no other optical
instrument than spectacles or the telescope, never the Microscope, of
which there is no mention whatever in any book published at that time,
nor in any manuscript known till then.”

But Rezzi was not mindful that on the 16th October, 1610, the date
of Wodderborn’s essay, the name of Microscope had not yet been
invented, nor that of telescope, which, according to Faber, was the idea
of Cesi, according to others of Giovanni Demisiano of Cephalonia, at the
end (perhaps) of 1610, but more probably at the time of Galileo’s
journey to Rome from the 29th March to the 4th June, 1611. If,
therefore, the word Microscope had not yet been invented, and if the
telescope or the occhiale, as it was then called, was by all named
perspicillum, one cannot see why Wodderborn’s perspicillum cannot have
been a cannocchiale (telescope) smaller than the usual ones, so that it
could easily be used to look at near objects, but yet a cannocchiale with
two lenses, one convex and one concave like the others, and, therefore,
a real compound Microscope, although not mentioned by that name either
by Wodderborn or others. And besides that, how could it be that
Wodderborn beginning to treat ‘‘ Admirabilis hujus perspicilli,” that is,
of the telescope in the first line, should then have called perspicillum a
single lens in the eleventh line of the same page? Rezzi’s mistake is
easily explained, remembering that he had not under his eyes Wodder-
born’s essay, but only knew a brief extract reported by Venturi. (17)

Less excusable is Rezzi’s remark, that Galileo had been led to make
a Microscope of the one objective lens (perspicillum) of his telescope,
by a letter of Magini of the 28th September, 1610,(18) in which the
astronomer of Bologna tells him that, “ Hlongating the tube to double
the distance from its point of sight, and taking away the traguardo or
concave lens, one sees everything upside down, and very distinct although
very small.”

The cannocchiale, or rather the objective of the cannocchiale, used
in such a way to observe with the naked eye the reversed real image of
the object, would have been a singular discovery for better examining
small objects, as instead of showing them larger they would have looked
smaller than when observed by the naked eye. But Magini was not
aware that only the images of those objects looked smaller which were
placed in front of the objective lens at a distance greater than double
its principal focus, whilst the images of objects situated between that
distance and the focus of the lens were enlarged relatively to the object
from which they originate, although always reversed. But even if he
had known this peculiarity, it could not have suggested the idea of a
simple Microscope, for with this one does not look at a real image, but
at a virtual image of the object; not at a reversed image, but at one

580 SUMMARY OF CURRENT RESEARCHES RELATING TO

erect; not at an image now less and now greater than the object, but an
image always larger than the object from which it arises.

Magini’s observation could not therefore suggest to Galileo the idea
of a simple Microscope, for it was the very opposite of it, and further
because the simple Microscope was at that time (as will be shown) an
invention more than three centuries old. We see from this that the

ood Abbé Rezzi must have been a most learned man, a man of letters,
but totally ignorant of the elements of optics, for we cannot suppose him
animated by the desire to deprive Galileo of the honour of having
invented the compound Microscope.

As, however, amongst those not versed or badly versed in the sub-
jects and language of science, many may in good faith repeat the words
and arguments of Rezzi, thinking them correct, it is necessary to fully
understand the meaning of the expressions simple Microscope and com-
pound Microscope, so that in the future the like errors should not be
renewed. .. .*

A single lens used to see, enlarged, the images of objects is called a
simple Microscope, but the same name is sometimes given, though
wrongly, to the ensemble of several lenses placed one over the other
provided they are close together or the intervals separating them are
very small relatively to the focus of each lens, because then the different
lenses act as if they were a single one of shorter focus than each
individual one.

We call a compound Microscope one to form which several lenses
are used separated by considerable intervals, whether these lenses are of
the same or of different kinds, the lens on the side of the object being
called the objective, and the one next the eye the ocular. . . .f

Having in such a way determined what is meant by simple Microscope
and compound Microscope, we must first of all find out to whom we owe
the invention of the simple Microscope.

Although it results from a passage of Seneca(20) that the ancients
had noticed the apparent enlargement of objects seen through a spherical
glass vase full of water, yet the fact of there being no mention of lenses
in the Optics of Euclid, nor in those of Heliodorus of Larissa, nor in
Damian, nor in what remains of the Optics of Ptolemy, and what is
more, the reasons adduced with great erudition by Thomas Henri
Martin in his dissertation (21) sufficiently prove that the ancients had
no lenses properly so called, and that therefore they did not know
either simple or compound Microscopes.

In spite of this it will not be inopportune to mention briefly here
the pretended concave emerald lens, which several writers, even very
recent ones, quoting Pliny, have supposed to have been used by Nero to
watch the fights of the gladiators.

The celebrated naturalist of Como, speaking ‘De pee eens
oculorum,’ lib. xi. 53 et seq., says first of all that “alii contuentur
longinqua, alii nisi prope admota non cernunt;” then he adds a little
further that Nero’s eyes were (ib., 54) ‘nisi quum conniveret, ad prope
admota, hebetes,” that is, that Nero’s eyes were only able to see near
objects when he half closed them, or, in other words, Nero was a
myope, for half shutting the eyes or bringing the eyelids together is of
no use to long-sighted people to see objects near them, or even to look

2 = few paragraphs which deal with elementary points are omitted here.
+ Ibid.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 581

at objects at a distance. This interpretation of the passage of Pliny is
confirmed by the words of the preceding paragraph (ib.,53): “oculi. ..
in homine . . . prominentes, quos hebetiores putant, etc.;” but promi-
nent eyes are almost always short-sighted eyes, and therefore the
epithet hebetiores corresponded to short-sighted ones; and Nero’s eyes
having been called hebetes in the passage quoted just before, will have
been short-sighted, which is also asserted by Suetonius, (22) who says
(“oculis cxsiis et hebetioribus”), with sea-green or pale-blue eyes,
and very weak, that is, only good for seeing very near objects, or in
other words, with the eyes of a myope.

And that the epithet hebes (blunt, obtuse, inefficient, weak, &c.)
applied to the eye did with the ancients correspond to our word
myope we have another proof in this, that up to the beginning of the
seventeenth century they continued to call weak sights, and spectacles
for weak sights, the eyes and spectacles of the short-sighted. (23)

That other passage of Pliny also clearly makes allusion to Nero’s
short sight (Ixxxvii. 16), which has made many believe that the ancients
were acquainted with concave lenses, and used them to lengthen the
sight of short-sighted people. This passage of the celebrated naturalist
says that these emeralds “quorum .. . corpus extensum est (eadem,
qua specula, ratione), supini imagines rerum reddunt. Nero princeps
gladiatorum pugnas spectabat smaragdo.” “These emeralds, which are
sufficiently large (acting like looking-glasses) placed with the re-
flecting face upwards, give the images of things. The Emperor Nero
watched the fights of the gladiators with an emerald.”

Now, speaking in this passage exclusively of emeralds large enough
to be used as mirrors, one cannot understand how with some learned
men these mirrors in passing through Nero’s hands can have become
lenses. Pliny speaking therefore in this place not of a lens but of an
emerald mirror, every one will easily understand that a mirror would
have been useless to Nero, if he were long-sighted; for neither a plane
nor a convex nor a concave mirror would have been of any use to a
long- sighted person to look at things a long way off, for a long-sighted
man sees far without any aid whatever.

On the other hand, if Nero was short-sighted, an emerald with its
top surface worked spherically with its face uppermost, as Pliny says in
front of and below the two eyes, or it might be below the one, could
have perfectly fulfilled the office of a concave lens, and present the
short-sighted emperor at a few centimetres from his eyes the images of
the amphitheatre, and of its distant gladiators, and enable him thus to
see them distinctly. The same effect might have been produced by an
emerald, plane on the side turned towards the eyes and the objects to be
viewed, and spherically concave beneath, as according to Pliny many
were then made (xxxvii. 16): “idem (emeralds) plerumque et concavi ut
visum colligant.” “One often finds some (emeralds) concave to collect
sight,” that is, it shows many things in a small field, for in that case the
reflection takes place on the convex surface of the scooped-out face, and
the light in passing from the emerald to the air must have been strong,
and given rise to virtual images very clear and close to the eyes of
the observer. (24)

One must not think emeralds large enough to serve as looking-
glasses with convex surfaces especially rare, as there are emeralds ten
centimetres long and five wide, others five long and three wide, (25) not

582 SUMMARY OF CURRENT RESEARCHES RELATING TO

to mention emeralds (?) four cubits long and three wide, and others
larger still mentioned, although doubtfully, by Pliny and Theophrastus.

We must, however, note that the ancients confounded many different
stones under the name of emeralds, and who knows how often they may
have also given the name of emeralds to glass tinted a beautiful green,
as the sacred basin in green glass in the possession of the Genoese was
believed to be and is still reputed by many an emerald. The Genoese
obtained it in 1102 from Cesarea, where it passed for the cup of
Christ’s Last Supper.

The ancients therefore had no lenses either convex or concave, or at
least no document is extant to show that they had any or knew how to
use them.

With the decadence of the Roman power the arts and sciences fell
also, and when the seat of the Empire passed from Rome to Constanti-
nople, night fell on the intellectual world, and the nations tossed in a
long and fearful sleep, during which only torments and prodigies were
invented.

The beginning of the middle ages was really the age of darkness,
but after the year 1000 minds having reopened to hope and intellects to
study, there began to dawn some light of science, so that in 1276 a
Franciscan monk, Roger Bacon, of Ilchester, in his ‘ Opus Majus,’ dedi-
cated and presented by him to Clement IV., (26) could show many
marvellous things, and amongst these the efficacy of crystal lenses, in
order to show things larger, and in this wise he says make of them “ an
instrument useful to old men and those whose sight is weakened, who
in such a way will be able to see the letters sufficiently enlarged, how-
ever small they are.” As long as no documents anterior to him are
discovered, Roger Bacon may be considered the first inventor of con-
vergent lenses, and therefore of the simple Microscope, however small
the enlargement by his lenses may have been.

As, however, that man of rare genius, the initiator of experimental
physics, had brought on himself the hatred of his contemporaries, they
kept him for many years in prison, then shut him up in a convent of his
order to the end of his long life, of nearly eighty years. His writings
had to be hidden, at least those treating on natural science, to save them
from destruction, and so the invention of lenses, or the knowledge
of their use to enlarge images and to alleviate the infirmities of sight,
remained unknown or forgotten in the pages of the famous ‘Opus Majus’
which only came to light in 1733, by the care of Samuel Jebb, a learned
English doctor.

A Florentine, by name Salvino degli Armati, at the end of the
thirteenth century (1280 ?) (in Bacon’s life-time), had therefore the glory
of inventing spectacles, and it was a monk of Pisa, Alexander Spina, who
suddenly charitably divulged the secret of their construction and use.

Perhaps Salvino degli Armati and Spina really discovered more than
Roger Bacon hal discovered ; that is, they found out the use of converg-
ing lenses for long-sighted people, and of diverging lenses for short-
sight, whilst the English monk had only spoken of the lenses for long
sight, and perhaps they added to this first invention the capability of
varying the focal lengths of the lenses according to need, and the other
of fixing them on to the visor of a cap to keep them firm in front of the
eyes, or to fasten them into two circles made of metal, or of bone joined
by a small elastic bridge over the nose. However it may be, the

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 583

discovery of spectacles, or as it may be called, of the simple Microscope,
may be equally divided between Roger Bacon and Salvino degli Armati,
leaving especially to the latter the invention of spectacles.

The first lenses for spectacles were it seems made from rock crystal
and beryl, and either because they believed those made of glass hurtful
tu the sight, or void of any virtue, or in order to prevent the fraud of
giving glass for crystal, Venice, in April 1300, (27) strictly prohibited
glaziers selling, as if made of crystal, the rotelle da occhi (roidi da ogli),
round shields for the eyes, and le pietre da leggere (lapides ad legendum),
reading-stones.

But a year later, 15th June, 1301, the old Giustizieri who superin-
tended the arts, allowed every one to make Vitreos ab oculis ad legendum,
on condition that they should be sold as glass and not as crystal; and in
March 1317, they granted the privilege of making oglarios de vitro, and
to sell them in Venice in spite of the chapter of the guild of crystal-
makers.

The first lenses having been cut in beryl or in rock crystal, led
them to be indifferently called Berilli, as in those days very different
gems were confused under the same name, and in Germany the word
Brillen has remained for all lenses, whilst the French for the same
reason first called spectacles Bericles, and then Bésicles (by corruption),
which the Piedmontese in their dialect used to call and still call
Buricole. Nicolo Krebs, from Cuss, better known under the name of
Nicolo Cusano, who lived from 1401 to 1464, called one of his writings
Berillo, because, thanks to its help, things otherwise incomprehen-
sible could be understood, and in the second chapter of this book he
says (23) :-—

“The beryl is a resplendent, colourless, and transparent stone, to
which is given a concave or convex form, and those who look through it
succeed in discovering things at first invisible.”

De la Borde (29) quotes a passage of a certain writing of the
sixteenth century, in which the cost is mentioned: “ Pour dix paires de
lunettes apportées & deux fois audit Seigneur Roy audit lieu de Bar,
dont y en avoit trois paires de cristal et les autres de béril.” (‘For ten
pairs of spectacles brought at two different times to the said Lord the
King, at the said place of Bar, of which three were crystal and the others
beryl.”

This shows that in those days they continued making lenses of
crystal and beryl for those gentlemen who could afford them. Little by
little, however, the use of beryl lenses disappeared, and even rock-
crystal ones have become rarer, although they are still made especially
to prevent their being scratched or dulled too soon by use.

But if from the time of Roger Bacon it was known that convex
lenses enlarged the images of objects, (80) so that one could obtain en-
largements of objects from five to ten times, and therefore one could with
them see small objects sufficiently enlarged, yet no advantage for the
knowledge and study of nature could be derived from them. One pos-
sessed the simple Microscope, but the observers and the observations
were wanting.

Girolamo Fracastoro, in his book on ‘ Omocentrici,’ published in 1538
(chapter vii.), says that, “Per duo specilla ocularia si quis perspiciat,
altero alteri superposito, maiora multo, et propinquiora videbit omnia.”
And a little further on, chapter xxiii, “Quinimo quedam specilla

584 SUMMARY OF CURRENT RESEARCHES RELATING TO

ocularia fiunt tante densitatis ut si per ea quis aut Lunam, aut aliud
syderum spectet adeo propinqua illa judicet, ut ne turres ipsas excedant ”
—words which, misunderstood by some, made people believe that Fracas-
toro was aware of the telescope, whilst in this passage he only makes
mention of simple lenses, and like one who did not know the theory of
them and had studied insufficiently their effects, exaggerates their efficacy,
imagining lenses powerful enough to enlarge the moon, as simple
spectacles or as two spectacles placed one over the other enlarge the
letters of a book.

Giambattista della Porta repeated later in his ‘ Magia Naturale’ (31)
the same things, and almost in the same words, so that many (and
amongst others Kepler) attributed to him the invention of the Dutch
telescope, which he himself (after having seen it once) imagined he
had invented, although Stotiola his friend relates (382) that he died
of fatigue in trying to discover the cause of it, which he could not
fathom.

The man who under the name of Alimberto Mauri dictated some of
the ‘ Considerazioni sopra alcuni luogi del Discorso di Lodovico delle
Colombe intorno alla stella apparita nel 1604 (‘ Reflections on some
passages of the Discourse of Lodovico delle Colombe about the star
which appeared in 1604’), (83) speaks also in 1606 of the enlargement
obtained with the lenses of spectacles, and therefore with the simple
Microscope. Delle Culombe suspected this to have been suggested if
not written by Galileo. (34)

* Although,” says Mauri, “spectacles were discovered for the first
time in 1280, (85) nevertheless their use having in this long lapse of
time entirely fallen to base objects, has never been, until now by you,
employed and adapted in favour of astrology and high and celestial
things.”

And here, in order to dissipate the suspicion that Delle Colombe
had invented the telescope in 1605, one must know that Alimberto
Mauri, by the words now quoted, wished to ridicule a strange thought
of Delle Colombe, who to explain the appearance of the new star of 1604,
attributed the function of a large lens to a part of the “crystalline
heavens” interposed between our eyes and the “ primum mobile,” where
the new star was situated.

‘« Because,” says Ludovico delle Colombe, (36) “ in the case of an object
which is not seen on account of its distance, if we come near to it, or if
the transparent medium through which we look magnifies it, we see it
as distinctly as objects are seen clearly and as if they were near, by
those persons who having short sight, by means of spectacles which
represent visible objects magnified, discover those things which without
the aid of such means they could not see... .

“It therefore appears that the new star and other similar stars which
have appeared at divers times, and which may possibly be seen here-
after, are true and real stars created in the heavens from the beginning,
but in the primum mobile, and rendered visible by some denser parts of
the crystalline heavens situated beneath.”

In the year 1612 they used without doubt lenses or simple Micro-
scopes to see things enlarged, for Boccalini in his ‘Ragguagli di
Parnasso,’ published | that year, writes thus :—

“ But most admirable are those occhiali, made with such art that
they make fleas look like elephants, pigmics like giants. These are

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 585

eagerly bought up by some great folks, who placing them on the nose
of their unfortunate courtiers so alter the sight of the wretches that
they esteem the low favour of being slapped on the shoulder by the
master, or being looked at by him with a grin even artificial and forced,
worth the remuneration of an income of five hundred crowns.”

Which passage reproduced in the 2nd edition of the same Collec-
tion, published in 1614 (‘ Ragguaglio primo,’ p. 4, line 4 and following),
continues thus :—

‘“‘ But the occhiali lately invented in Flanders are bought at a high
price by these same personages and then made a present of to their
courtiers, which when used by them make them see as very near them
those prizes and those dignities which are not within reach of their
sight, and which may never be within reach of their age.”

From this addition of Boccalini’s one sees that in the first passage
the word occhiali is used for lenses and not telescopes as some believed,
through reading only the first edition of the book, since the telescope
is clearly indicated in the addition, it being called “ occhiale lately
invented in Flanders.”

We may therefore conclude from what has been said that although
lenses for the enlargement of objects had been discovered, their use
was scarcely understood, and they were only used for base objects as
Alimberto Mauri affirms, without any one thinking of using them to
increase our knowledge of the smaller details of large objects, or the
existence of very small objects undiscernible to the naked eye.

Many strange ideas were mooted in those times concerning lenses
(and some have been seen in the preceding quotations), because all who
had made use of them had confused the enlargement of the ocular image
produced by the lens with the approach of the same image to the eye,
although these two things are completely different.

When an object is examined through a convex lens, and the enlarged
virtual image of the object is seen, instinct makes us believe it to be
very near, although at times it is really at an infinite distance, and the
eye adapts itself to look at it at that distance, as if it were looking
without the aid of a lens at an object at a great distance. This sensa-
tion (or rather this invincible feeling of a sensation, invincible even for
those who know quite well that converging lenses make us see the
object far more distant from the eye than it really is) springs from our
powerlessness to estimate distance at sight, especially in the case of
rather long distances and of things looked at with only one eye, if the
apparent size of the object does not help us to judge its distance better.
Now on looking through a converging lens the objects almost all appear
to us of the same size, whether their image is formed quite close to the
eye or at an enormous distance. (37)

In this way, comparing through a lens a very large object with its
more minute details, which we know to be small, and not being able to
recognize the true place of. its image, we believe it to be near, although
it is always further off than the object from which it arises.

The contrary happens with diverging lenses, which, producing on
the retina a smaller image than would be shown to the naked eye by the
object observed if it were placed at the same distance at which its image
is formed, we imagine the image to be very distant, whilst it really is
always nearer the eye than the object seen.

This illusion concerning the real distance of images contemplated

586 SUMMARY OF CURRENT RESEARCHES RELATING TO

through a lens explains the expressions already quoted, from Roger
Bacon, Fracastoro, del Porta, Lodovico delle Colombe, and Alimberto
Mauri, who repeatedly mention images brought near and enlarged by
the use of converging lenses, and they show their belief that with
appropriate lenses one can bring nearer and then enlarge the images of
most distant objects, and especially of the stars. These expressions
only really reveal the lack of knowledge in those times of the manner
in which vision is effected, and of the function of lenses in the forma-
tion of images.

From all that we have now set forth it appears sufficiently demon-
strated that at the beginning of the seventeenth century they had already
possessed for more than 300 years lenses capable of enlarging the
images of objects, that this enlarging power of the lenses was known,
but that no one until then had made any use of it as a simple Microscope
to study things more minutely and to progress in the knowledge of
nature. (38)

It was the discovery of the Dutch telescope, and still more the
celestial discoveries made by Galileo, which drew the attention of the
learned towards lenses and their properties, and the passage of Wodder-
born, mentioned at the beginning of this paper, permits us to affirm that
if the Florentine philosopher was not the inventor of the telescope (as
he has himself candidly declared in many places), he was without doubt
the inventor of the compound Microscope, having used from 1610 a
Dutch telescope to look at near and minute objects, and having discovered
with it various details unknown by him till then in some common
animalcules, on which the learned men of those days did not deign to
fix their eyes, intent as they were in seeking the origin, reason, and
properties of things in Aristotle's Category and in the artifices of
laboriously barren dialectics.

Contrary, therefore, to the conclusions of the Abbé Rezzi, we must
affirm that Galileo did not invent the simple Microscope, because it had
already been invented for centuries, but invented instead the compound
Microscope with a convex and a concave lens, and was the first to make
use of it to increase our knowledge of natural things.

To better secure for Galileo the invention of the compound Micro-
scope one might have quoted also the words of Viviani in the life of his
master published by Salvini in the ‘ Fasti Consolari, (89) and those
placed by the same Viviani on the front of his house in Florence in Via
Sant’ Antonino (formerly Via dell’ Amore), No. 18.(40) But the
enthusiastic admiration of Viviani for Galileo has made him many times
fall into such exaggeration with regard to Galileo’s discoveries, that it
lessens the authority of his words, especially in the matter of optics, of
which it does not appear from his writings that Viviani ever understood
very much.

Neither, for the same reason, will we quote the ‘Oratio de Mathe-
matic laudibus habita in florentissima Pisarum Academia cum ibidem
publicam illius scientize explicationem aggressus foret” (Rome, Typo.
Jacobi Mascardi, 1627, 4to) of Niccold Aggiunti, disciple of Galileo,
although it may be useful to recall the passage where Aggiunti, speaking
of Galileo's Microscope, says, ‘“‘dudum vero telescopioli usu ita sensum
visus exercuimus, etc. etc.,” for also from these words, pronounced in
1626, one finds that the occhialino of Galileo was a small telescope
(telescopiolum, a» word which for Aggiunti, as for others, then meant only

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 587

the Dutch telescope), and therefore differed, as before stated, from
Drebbel’s Microscope.

On the other hand, no testimony in favour of Galileo’s invention can
be more explicit and more sure than Wodderborn’s, corroborated by
Galileo’s own declaration in 1624, after he had seen Drebbel’s Micro-
scopes, as referred to by Aleandro.

As to the pretensions put forward by Pierre Borel in favour of
Janssen, (41) or to the boasts of Francesco Fontana, (42) it will suffice
to show how the first were only put forward in 1655, that is, half a
century after the supposed invention, and the others in 1646, after
Fontana had had notice of Drebbel’s Microscopes in 1625, indeed had
seen some in Fabio Colonna’s house without at first understanding the
meaning of them, as is shown by certain letters of Colonna, which were
printed in the last century in the ‘ Giornale dei Letterati’ of Rome. (48)

D. Chorez, Drebbel, and Fontana, who after 1610 made Microscopes
with a convex and a concave lens, were not inventors, but reproducers of
Galileo’s compound Microscope. Others coming later, without usurping
the invention of Galileo, spoke of it without giving itas his. So did
Manzini in his ‘ Occhiale all’ occhio’ (1660), and I am convinced that
in looking through the writers on optics after Manzini we should find
several who since that time described Galileo’s Microscope without
attributing it to its real author. (44)

Also the ingenious French optician Charles Chevalier, in his
‘Manuel du Micrographe,’ published in 1839, brought forward again
as a novelty the Galilean Microscope, being ignorant without doubt that
the invention was over 200 years old.

Latterly the same thing happened to the celebrated German physio-
logist Ernest William Briicke, whose “ working lens,” which now all
naturalists know under the uname of the “ Briicke lens,” is really
nothing but the ancient “ occhialino” of Galileo, modernized in shape,
with better lenses, and limited to lesser amplification.

At the meeting of the 8th May, 1851, Prof. Briicke (45) presented
to the Academy of Sciences of Vienna a species of Microscope, termed
by him working lens (Arbeitsloupe), intended to facilitate anatomical
studies, because it has a large frontal distance, in spite of its amplifying
power of six and more diameters. This working lens consisted of a
brass cylinder 90 mm. long and 40 mm. in diameter, which had at one
extremity a couple of achromatic lenses taken from an aplanatic ocular of
a large compound Microscope of Plossl, and at the other extremity a
biconcave lens taken from an opera-glass. The two converging glasses
placed together acted as a single lens, but rendering the field of vision
more uniform and clear. The objects to be observed were placed at
75 mm. from the objective, and appeared to be enlarged 5 times at
165 mm. distance from the eye, and about 6°6 times at 8 Parisian
inches, or 216°56 mm. from the eye.

If the same enlargement at the same distance was wanted with a
single lens, a lens of 41°25 mm. principal focal distance would have to
be used, holding it at 33 mm. instead of 75 mm. from the object. And
if placing the object at 75 mm. from a lens we had tried to enlarge it
5 times, we must have had recourse to a lens with a focus of 93:74 mm.,
and a virtual image five times as large as the object would have been
formed not at 165 mm., nor at 217 mm., but at 375 mm. from the eye.
In either case the observer would have been inconvenienced either by

588 SUMMARY OF OURRENT RESEARCHES RELATING TO

the too great proximity of the object to the lens or by the too great
distance of the image from the eye. JBriicke’s idea therefore was
excellent, and anatomists, physiologists, botanists, and naturalists, who
continually use that small Microscope (microscopietto) of his, have
justly, out of gratitude, called it “ Briicke’s lens.”

But properly speaking, however, this lens is only a telescope of
Lippersheim or of Janssen, and therefore a Microscope of Galileo.
“Tt is clear (says Briicke himself) that it depends on the same principle
as the Galilean telescope. The compound Microscope is an astrono-
mical telescope whose objective has a very short focus; if instead one
gives a very short focus: to the objective of a Galilean telescope, we
obtain the lens just described.”

This frank confession of the celebrated physiologist proves with
what candour he admitted having first used as a Microscope the Dutch
telescope, and does not even allow the suspicion that he had had the
least idea that Galileo had been before him even since 1610, that is, in
the year of his wonderful discoveries in the heavens. We must not,
however, deprive Briicke of the merit of having invented for the second
time the Microscope, composed of a convex and a concave lens, all the
more so, as his “working lens” is not intended to examine small objects
or to see invisible things, but has been made and is used for anatomizing
at some distance on those organs or those tissues which only demand a
small enlargement to be sufficiently recognized.

APPENDIX.

Whilst this paper was being printed, Prof. Antonio Favaro with
great kindness communicated to me an important passage, the better to
confirm Galileo as the inventor of the compound Microscope. This
passage is taken from certain ‘ Relazioni dei Viaggi’ of Giovanni du
Pont, Seigneur de Tarde, Canon of the Cathedral of Sarlat (Dordogne),
‘Relazioni’ which are in MS. in the National Library of Paris (Fonds
Périgord, t. vi. cart. 20 and following). From these ‘Relazioni’ it
appears that on Tuesday, November 11th, 1614, Tarde arrived at
Florence, and on Wednesday the 12th went at once to visit Galileo,
who was ill in bed. After having spoken with him about the Celesti
discoveries, Tarde relates that Galileo told him :—

“‘Que le canon du télescope pour voir les estoiles n’est pas long plus
de deux pieds, mais pour voir les objects qui nous sont fort proches et
que nous ne pouvons voir 4 cause de leur petitesse, il faut que le canon
aye deux ou trois brasses de longueur. Avec ce long canon il me dict
avoir vu des mouches qui paraissent grandes comme un agneau et avoit
appris quelles sont toutes couvertes de poils et ont des ongles fort
pointues, par le moyen desquelles elles se soutiennent et cheminent sur
le verre, quoique pendues 4 plomb, mettant la pointe de leur ongle dans
les pores du verre.” (“That the tube of a telescope for looking at the
stars is no more than two feet in length, but to see objects which are very
near, but which we cannot see on account of their small size, the tube
must have two or three lengths. He tells me that with this long tube
he has seen flies which look as big as a lamb, and had learned that they
are all covered over with hair, and have very pointed nails, by means

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 589

of which they keep themselves up and walk on glass, although hanging

feet upwards, by inserting the point of their nail into the pores of the
lass.”

Therefore in 1614 Galileo had not forgotten his Microscope of

1610, and spoke of it pretty much in the same terms as he did after-

wards in 1624 to Aleandro, Faber, and Cesi.

Another document, discovered by Prof. Favaro in the National
Library at Florence (Cod. viii. F. 2), and by him also kindly passed
on to me, speaks of three ‘Occhiali detti di moltiplicatione’ sent to the
Grand Duke from countries beyond the mountains; and Agnolo Marzi
Medici, author of the document, adds that he cannot say how these
occhiali are made, being forbidden to do so, “ because they want to see if
Galileo will be able to discover it, as it is over a month sincc he is
working at it, and so far nothing has been seen.”

Now, although the document has no date, I think we may unhesitat-
ingly attribute it to 1624, in the interval between the 11th of June,
when Galileo left Rome to return to Florence, and the 5th of September,
the date of Bartolomeo Imperiali’s letter thanking Galileo for the gift
of an occhialino. Galileo himself, writing to Cesi, September 23rd,
excuses himself for the delay in sending the occhialino because he had
not sooner brought it to perfection. Now, starting from Rome on the
15th of June, and this may be seen from a letter of Mario Guiducci,
11th of June, Galileo would not have reached Florence before the
21st June, and of one by Ciampoli (‘Carteggio Galileano,’ of Campori,
p- 206), who thanks Galileo for having received news of his safe
journey.

On the 9th August Antonio Santini wrote from Genoa to Galileo to
thank him for having had the occhialino perfected for Imperiali
(ib., p. 211), and as Santini answered a letter of Galileo of the 24th
July, so we must suppose the occhialino to have been finished at least
on that day. Butif Imperiali’s occhialino was finished on the 24th of
July, we must admit that shortly after the middle of July Galileo had
already found a means of bringing it to perfection. One can therefore
conclude that Marzi-Medici’s ‘ Scritto,’ written a month after the time
Galileo had set to speculate on and work at the occhialino, must be
placed about the 15th July (a month, that is, after Galileo’s arrival at
Florence), when he was intending to reduce his Microscope to per-
fection.

On the other hand, the arrival in Florence of “ occhiali di moltiplica-
tione ” from regions beyond the mountains cannot be placed anterior to
the introduction in Italy of Drebbel’s Microscope, that is before 1624;
and in 1624 Marzi-Medici, secretary to the Grand Duke Ferdinand IL.,
and author of the document, was still alive, as it appears from a certain
catalogue of Salvini that he died on the 31st October, 1628; we can
therefore assign with certainty a date very near the 15th July, 1624,
to the curious MS. discovered by Professor Favaro.

[NOTES.
1889. 23

590 SUMMARY OF CURRENT RESEARCHES RELATING TO

NOTES.

(1) ‘ Bulletino di Bibliografia e di Storia delle Scienze Matematiche e Fisiche ”
t. xiii. (August 1880, pp. 471-80). “ Nuovo documento relativo alla invenzione dei
Cannochiali Binocoli, con illustrazioni dal Prof. Gilberto Govi.” (New document
penne to the invention of Binocular Telescopes, with illustrations by Prof. Gilberto

Ovi.)

(2) Ibid., p. 475, lines 9, 12.

(3) ‘Quatuor problematum que Martinus Horky contra nuntium sidereum de
quatuor planetis novis disputando proposuit confutatio; by John Wodderborn,
Scotchman. Patavii, Ex typographio Petri Marinelli, m.pc.x. superiorum permissu.’
1 vol. 4to, cart. 7 recto.

(4) Here is how he makes the Peripatetics, his contemporaries, speak in the
famous ‘ Dialogo dei massimi sistemi’:—‘“‘'To speak with sincerity, 1 have not had
the curiosity of reading those books, nor have I so far put any belief in the
newly introduced Occhiale; indeed, following in the footsteps of other peripatetic
philosophers, my colleagues, I have believed to be fallacious or a deception of
glasses what others have admired as stupendous operations.” (‘ Dialogo di Galileo
Galilei Linceo ece., Fiorenza, 1632, 4to, p. 328, lines 1-6. Galileo Opere, last
edition of Florence, t. i. p. 366, lines 28-33.)

(5) Gal. Opere, t. viii. pp. 430-1. Ciampoli’s letter of December 6th,
1619 :—* Your Lordship’s answer is expected with the greatest anxiety.” Of course
this is the answer to Padre Grassi’s ‘Libra astronomica.’ Gal. Opere, t. viii.
p. 436. Letter of Francesco Stelluti of January 27th, 1620:—“‘ and because I have
heard that your Holiness had already begun preparing the answer, therefore, &c.,
&e.”

(6) Gal. Opere, t. vi. pp. 286-7. Galileo’s letter to Federico Cesi, of October 19th,
1622 :—“T have finally sent to the Illustrious Signor Don Virginio, the answer to
Sarsi.”

(7) “Il Saggiatore, nel quale con bilancia esquisita e giusta si ponderano le cose
contenute nella Libra Astronomica e filosofica di Lotario Sarsi Sigensano, scritta in
forma di lettera all Ill™- et Reuer™?: Monsr™®: D. Virginio Cesarini Acc? Linceo
Me: di Camera di N. S. dal Sig. Galileo Galilei Acc? Linceo Nobile Fiorentino
filosofo e Matematico Primario del Ser™?- Gran Duca di Toscana. In Roma 1623,
1 vol. 4to.

Tb., p. 105, lines 28-35 and Galileo Opere, t. iv. p. 248, lines 21-28.

(8) The letters of Aleandro to Pieresc, and those of Peirese to Aleandro have too
much importance for the argument under discussion to allow of our omitting the
extracts which treat of the Microscope. Peirese’s original letters are in the
Barberinian Library, and the passages here reproduced have already been printed by
the Abbé Rezzi in his “ Memoria” (see note 16), which is amongst those in the
‘ Accademia pontificia dei nuoyi Lincei,’ for the year 1851. But Rezzi changed the
spelling, and omitted some parts of them. :

We have thought it useful to reproduce from the original, the parts in Peiresc’s
letters, preserving the form intact, and adding those extracts which Rezzi had
suppressed.

Having then discovered among Pierese’s manuscripts, which are preserved in the
National Library in Paris, some of the letters sent to the learned Frenchman by the
Cardinal of Santa Susanna, and by Aleandro in answer to his, it has been thought
right to detach from them the passages relating to the Microscope, and to intercalate
them here between those of Peiresc, completing in this manner (as far as possible)
the history of the origin of the Dutch Microscope, or Drebbel’s Microscope, in Italy.

The extracts of Peirese’s letters are from the Codice N. A. 1975 of the Barberini
Library. Those from the Cardinal of Santa Susanna’s letters from the Codice No.
9536, Fond. franc. de la bibliotheque nationale de Paris. Those from Aleandro’s
letters from the Codice No. 9541, Fond. franc. of the same library. The different
passages have been placed in order of time, to render more clearly the history of
the facts relating to the invention of the Microscope.

Here are the documents. First letter of Peirese to Aleandro :—

“Most illustrious and most honoured Sir,—Your Lordship will receive the

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 591

present from the hand of Sig. G. Kuffler, of Cologne; a young man who is a good
catholic, of much virtue and much modesty, whom you yourself will judge worthy
of recommendation to virtuous people. He will be able to show your Lordship an
occhile or telescope of new invention, different from that of Galileo, with which he
shows a flea as large as a locust, those that have no wings and are called crickets,
and almost of the same shape, with its two arms and the other smaller legs, its
head and almost all the rest of the body covered and armed with crusts or scales like
locusts or small shrimps. ‘he little insects which generate in cheese and which
we call Mitte, Mittoni, or Artiggioni, which are so tiny that they almost seem like dust,
become as large as flies without wings when seen with that instrument, and are so
distinctly discerned that one recognizes them to have very long legs, a pointed head,
and every part of the body quite distinct, making one admire in the highest degree
the effects of divine providence, which was far more incomprehensible to us when
that aid to our eyes was wanting. I thought that your Lordship would see it with
pleasure, as did the Duke of Anjou, brother to His Majesty, and all the most curious
persons of this town, and as out of this kingdom the King of England, Prince
Maurice, and many other persons of great name have done; and I believe this invention
will not be held in less esteem by people in your town, especially by the illustrious
Cardinal of Santa Susanna, to whom I beg your Lordship to introduce this young
man, as well as to the illustrious Cardinal your master, and the illustrious Cardinal
Barberino, and others at your court, whom you will judge desirous of seeing it. He
has some other inventions, which he will in time bring to light, and which may
perhaps be even more successful, having learnt them from Sig. Cornelius Drubelsius,
his relation, one of the cleverest nen in this century in matters of mechanics, and
who has built boats that float under water, mirrors that burn at several miles’
distance, and other stupendous things; I will consider as dune to me the favour
and assistance he will receive from your Lordship, and I will consequently remain
under proper obligation to you. With which without adding further I kiss your
hands with all my heart, praying that Heaven may give you every perfect good.
From Paris, 7th June, 1622.—Your most illustrious Lordship’s affectionate servant,
Di PErREsc.”

From Peirese to Aleandro :—

“Paris, 8th December, 1622— . . . I am indeed sorry at the loss of poor Kuffler,
and that unfortunately he should not have been able first to show the illustrious
Cardinal of Santa Susanna and to your Lordship the marvellous effects of his
occhiale. I am ashamed now of having written to you the details about it that I did,
as I see you so far from being able to enjoy that instrument, as it is not credible
unless one sees it as soon as spoken of. It would have been a great consolation for
me if that relation of his who came’ from Naples could have made up for that de-
ficiency. In the meanwhile I do not know how to thank you worthily for all the
charity and liberality shown that poor man, as well after death as in lite, and I beg
you will receive the reimbursement from Sig. Eschinardo, and I will nevertheless
remain much obliged to you for your great courtesy aud singular promptness.”

From Peirese to Aleandro :—

“Paris, January 5th, 1623.—As to the occhiale which allows the most minute
objects to be seen so many times enlarged, I am extremely sorry that the illustrious
Cardinal of Santa Susanna and your Lordship never saw tle effect. 1 kept one, which
I have tried to have copied, and if I am successful, as I hope to be, I will not fail to
send one at once to the said Cardinal; indeed, if I do not succeed in my attempt, I
would rather resolve to send him mine, so that he may experience so miraculous an
enjoyment of the sense of human sight, for otherwise I would pass as an impostor for
having written what I first wrote to you on the subject, if I did not make him see it
and touch it, so to say, and I would deserve to lose credit in the future.”

From Peirese to Aleandro :—

“Paris, August 14th, 1623.—I wrote to your Lordship by Father Dom. Gio. di
San Paulo Vassano, in the beginning of July, a letter to be delivered in person with
the oechiale by Drebelsius which I had received from Kuffler, together with another
smaller ocehiale most easily worked, having shown him how to use it, so that it
might be easicr for your Lordship to explain it to the illustrious Cardinal of Santa
Susanna; and I thought that he must have already arrived, or be very near to Rome.
But now I am assured that he has remained half-way on account of the return on
this side of the mountains of the Father General of that Order, which displeases
me extremely. We shall have to await the effect of fortune which seems to have
persecuted this poor instrument.”

592 SUMMARY OF CURRENT RESEARCHES RELATING TO

From the Cardinal of Santa Susanna to Peirese :—

“Rome, September 16th, 1623.—I would have been very happy to receive the
two occhiali which you had entrusted to Father D. Giovanni, but which I believe
will not be brought by the Father, and nevertheless I wish that my obligations to you
be increased, &c., &e.”

From the Cardinal of Santa Susanna to Peirese :—

“Rome, September 25th, 1623.—About Father D. Giov. di San Paolo Vassano,
who was to have brought the Kufflerian occhiale, I never heard further than what
your Lordship wrote me, and provided he arrives some day, it will matter little,
although he may delay some months.”

From Peiresc to Aleandro:—

“Most Illustrious and Honoured Sir,—There has just now reached me a little
box from Father Vassano, containing the occhiale with his letters, and at the
same time the Avignon courier passing, I did not wish to let him go by without
sending you the said little box. Your Lordship will do me the kindness to receive
it and take the occhiale to the Illustrious Cardinal of Santa Susanna and show him
the use of it, if you can put it together by what I wrote concerning it; there were
other letters of introduction for the said Father, to different friends, to whom I believe
I mentioned the occliale, thinking that the Father could show it to all. I do not
know whether they will be in the box or not, having no time to look it through more
particularly. Your Lordship will be able to send them if so pleases you, by making
the occhiale the excuse; I think I wrote about it to his Holiness at the time he was
only a Cardinal, thinking he might experience pleasure in seeing the said occhiale,
and perhaps it will be better not to send him the letter, in order not to oblige the
Cardinal of Santa Susanna to send the occhiale I had given him, that he may not run
the risk of having to make a gift of it. I leave all to your discretion and many times
kiss your hands. Aix, November 17th, 1623.—Your most Illustrious Lordship’s
affectionate and grateful servant, D1 Prtrusc.”

(On the margin of the leaf on the left andacross.) “ My secretary has just assured
me that I wrote nothing abont the occhiale to the Ilustrious Cardinal Barberino,
and that I only recommended Father Vassano, so that it does not matter whether the
letter is given or nut.”

From Peirese to Aleandro:—

“ Aix, 7th Decewber, 1623.—Most Illustrious and Honoured Sir,—The ordi-
nary courier to Avignon was passing by this town in the greatest hurry at the very
moment that a box from the Rev. Father Dom. Giov. di San Paolo was being con-
signed to me, containing the o-chiale and the letters accompanying it. Which box I
closed at once, lookiug at nothing but the Father’s letter, and I consigned the whole
to the above mentioned courier, who persisted in going on his way and scarcely
allowed me to write two lines to your Lordship, whilst another person was closing
the box. I recommended the same to Messrs. Otto. and M. Anto. Lumaga of Genoa,
to whom your Lordship may henceforth forward whatever you wish to send me,
that way being shorter than the route by Lyons. The same courier passed
again last Sunday, and he brought me an answer from Genoa, from those Messrs.
Lumaga, that the box had arrived in good condition, and that they had consigned it
to a courier, a friend of theirs, to take it to your Lordship or to Sig. Eschinardo. I
rejoice in believing that it has now reached you, and that your Lordship will have
fuund out how the said occhiale can be used, and especially the little one, which is
very easily used and has an effect not far inferior to the large occhiale.”’

Letter of the Cardinal of Santa Susanna to Peirese :—

“Rome, December 26th, 1623.—Most [lustrious and Revered Sir,—I have to
hand two of your Lordship’s letters, the one of which represented to me the good
state of your health, since you have retired from exercising your charge in the
Parliament of Paris, for which I have felt the comfort that becomes the great affection
I bear you, and the continual desire which I have for your welfare; the other has
been brought to me with the occhiale; how dear this is to me your Lordship will
understand by the desire with which I expected it, expressed to you in my letters.
I would like you to recognize this fact more thoroughly by some act of mine in your
service. But until an opportunity to do so is given to me, I will beg you to be satis-
fied with my thanks, which 1 now here render you for your courtesy. I will
experiment on the occhiale with Signor Aleandro, and I will make use of this
beautiful invention. May the Lord preserve and prosper your Lordship as I
aeeire it. D.V.S. Rome, xxvj. December, 1623.—At your service, 8. Car. D1

. SUSANNA.”

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 593

Here there comes, in the series of letters from Peirese to Aleandro, a letter from
Aix of January 12th, 1624, in which Peiresc_ mentions again the courier of Avignon,
who took the box with the occhiali, as he speaks of it again in another letter of
February 18th, but neither one nor the other containing new particulars concerning
this subject, we have thought it useless to publish them. Between these two
letters must be placed the following from Girolamo Aleandro to Peirese :—

“Rome, February 2nd, 1624.— . . . With the same letter of the 2nd I received
the box with the occliali, which I took at once to the Cardinal of Santa Susanna,
and [I left in his hand your Lordship’s old letter in which you wrote in what way they
were to be used. It was easy to set up the little one, but we have not yet found the
way of using the large one, although we had the help of mathematicians, and we have
feared that in some part it is out of order. But the Cardinal of Santa Susanna will
have written to you more diffusely on all this. . . .”

From Peirese to Aleandro :—

“ Aix, March 3rd, 1624.—I am very much surprised that you have not managed
the large occhiale; if the glasses are not broken it is easy to find their proportion.
I will await the more ample relation which you tell me will be sent me by the Ilus-
trious Cardinal of Santa Susanna, in order to answer the difficulties and give some
means of obviating them, so that the instrument may succeed. The greatest difficulty
to the most perfect success lies in the movable plate upon which the object is placed,
so as to keep it motionless under the point at which the line which passes from the
eye through the centre of the two glasses terminates. For, when once one has learnt
the use of it, it is operated most easily and with great pleasure and delight; one sees
a tiny live animal walking and one retains it precisely under the line by moving the
little plate contrariwise to the place towards which the insect is directing itself.
Because the effect of the occhiale is to show the object upside down, and to cause
the real motion of the little animal to seem contrary; as for example, if it be going
from east to west it will appear to go from west to east. As to the distance of the
glasses from each other, there are two limits out of which they do not make any
considerable effect of increase and greater or lesser distinctness. And as to the dis-
tance between the object and the first glass, it must likewise be greater or less,
according to that of the glasses from one another; that is, if the distance of the
glasses between each other is the greater, the distance of the object must be less,
and as you decrease the distance between the glasses, so must you increase the
distance of the object.”

From Aleandro to Peirese :—

‘Rome, 29th March, 1624.—The large occhiale is unbroken, but we cannot
find a way of adjusting it rightly, because although we have directed the opening as
we ought to have done towards the object placed upon the little plate, and we have
also discovered the magnification, yet we did not sce it distinctly, though your Lord-
ship affirmed that it showed things more distinctly than the little one. We shall go
on trying it until we find the way. But it is a long time since 1 have seen the
Cardinal of 8. Susanna. . . .”

From Peirese to Aleandro:—

“ Aix, 15th April, 1624.—Postscript— Having remembered that Signor Melano,
bearer of the present, has formerly seen in my hand the occhiale of the Illustrious
Cardinal of 8. Susanna, I have gone over with him the way to work it, and if your
Lordship will let him see the occhiale again he will try it, and can direct your Lordship
and any one it may please you to show it to after the said Illustrious Sigt.”

From Peirese to Aleandro :—

* Aix, 10th and 17th May, 1624.—It is true that I wrote to you of the large
occhiale that one saw the object clearer than in the little one, but to have the full
effect of it, the object must be lighted up by the sun, otherwise it remains too dark.
But in the sun you will see a stupendous effect, when you have found the way to
use the instrument.”

From Aleandro to Peirese :—

“Rome, 24th May, 1624 ... Signor Melano, engraver on copper, came
afterwards to see me with your Lordship’s letter of the 15th, and I offered to serve
him and recommend him to Villamena, Tempesta, and to whomever he liked. He
told me he would return to sce me, but I have not seen him since. I will also take
him to the Cardinal of Santa Susanna. Galileo has been here these last few days,
and at once found how the occhiale was to be used, but we don’t think we see things
very clearly and we will try with Melano.

Galileo told me that he had discovered an occhiale which magnified these small

594 SUMMARY OF CURRENT RESEARCHES RELATING TO

things perhaps fifty thousand times, so that a fly is seen as large as a hen. He
remained here a few days, and returned to Florence. . . .”

Galileo left Rome only on the 11th June, but probably Aleandro had not seen
him after that visit to the Cardinal, and therefore thought he was gone.

From Peirese to Aleandro :—

“ Aix, July Ist, 1624.—As to the occhiale, I am pleased that Signor Galileo
understood it, but I am sorry that you should not have had as clear an effect as it
gives in its proper adjustment, if the object be lighted up by the rays of the sua.
Perhaps Signor Melano will be of some use to you if you will try him. In the
meanwhile I thank you for the kindness shown to Signor Melano. But the occhiale
mentioned by Signor Galileo, which makes flies as large as hens, is of the same
invention as this one, of which the author made a copy. for the Archduke Albert,
of pious memory, which used to be placed on the ground, when a fly was seen the
size of a hen and the instrument was no higher than an ordinary dining-table.”

(9) Rezzi (see note 16), speaking (p. 102) of the Cardinal of Santa Susanna, calls
him Girolamo Rusticucci, whilst in 1622 Scipione Cobellucci, from Viterbo, was the
Cardinal bearing that title, having been made cardinal by Paul Y. on the 19th
September, 1616. Cobellucci died on the 29th June, 1626.

(10) Don Baldassare Boncompagni, with that great kindness which he has always
shown me, has generously allowed me to make notes of all those facts which might
be useful to me, from the very precious collection of MSS. which he possesses, and
for a part of which there is a printed catalogue, compiled with great care and
erudition by Sig. Enrico Narducci. In this collection is to be found a volume
entitled, ‘ Lettere di molti accademici Lyncei scritte al Sig. Principe Cesi fond di
detta Accademia’; it is from this volume that I have extracted the passage of
Faber’s letter reported in the text, and several other extracts of letters which are
also here reproduced, and which are indicated as drawn from the Codice
Boncompagni.

(11) Cardinal Zollern (Itelio Federico, Count of), made cardinal by Paul VY. on
January 11th, 1621, received the hat from Gregory XV. on November 15th, and the
title of San Lorenzo in Panisperna, December 15th of the same year. He died on
the 19th September, 1626. at Osnabriick, where he was bishop.

(12) As to Galileo’s Microscope, which he asserted enlarged objects 50,000 times
(in volume that is, 36 times in diameter), we have no other data except this of its
magnifying power, and (from one of Peiresc’s letters), the distance from the object to
the ocular, a distance pretty nearly equal to the height of a dining table (which is
genera ly 80 centimetres). This is supposing that Galileo’s “ Occhialino ” of 1619,
and the Microscope mentioned by Peiresc were one and the same thing. Making
use of these two indications, and the distance of the object from the objective being
taken arbitrarily, we can calculate its focal length. .. .

Galileo could therefore very well have constructed in 1610 a Microscope maeni-
fying 36 times, with the concave ocular 80 centimetres from the place occupied by
the object. The length of the Microscope, that is, the distance of the objective from
the ocular, would have been 40 centimetres.

(13) Here are the books in which the different letters quoted in the text are to be
found. :

Letter of Bartolomeo Imperiali, Gal. Opere, t. ix. pp. 64-5; of Galileo to
Federico Cesi, Gal. Opere, t. vi. pp. 297-8; Federico Cesi to Galileo, Gal.
Opere, t. ix. p. 71; Bartolomeo Balbi to Galileo, ‘ Lettere inedite a Galileo Galilei
raccolte dal Dott. Arturo Wolynski,’ Firenze, 1872, letter 126, p. 75; of Galileo to
Cesare Marsili, Gal. Opere, t. vi. p. 301.

(14) ‘Nova Plantarum, Animalium et Mineralium Mexicanorum Historia, a
Francisco Hernandez Medico in Indiis prestantissimo primum compilata, dein a
Nardo Antonio Reccho in volumen digesta, a Jo. Terentio, Jo. Fabro, et Fabio
Columna Lynceis, notis et additionibus longe doctissimis illustrata. Cui demum
accessere aliquot ex Principis Federici Cesii Frontispiciis Theatri naturalis Phyto-
sophicee Tabulz, una cum quampluribus Iconibus, ad octingentas quibus singula
contemplanda graphice exhibentur. Rome, mpcui. sumptibus Blasij deuersini et
Zanobij Masotti Bibliopolarum. Typis Vitalis Mascardi.’ 1 vol. fol.

The title of the edition of 1630 was rather different, and appears on the second
leaf of the volume, engraved on copper by Federico Greuter. Omitting the details
relating to the different writers of the work, this title is as follows :—

‘Rerum Medicarum Nove Hispanie Thesaurus, seu Plantarum, Animalium,
Miveralium Mexicanorum Historia. Rome, ex typographcio Jacobi Mascardi,

ZOOLOGY AND BOTANY, MICROSCOPY, ETO, 595

mpcxxx.’ To this original date were added in 1651 the numerals xxr. to
compose the new date. In the frontispiece (engraved on copper) of 1630, Joanne
Terrentio is correctly written, but in the frontispiece to the print of 1651 is changed
to Terentio.

(15) The “ante pauculos dies ” placed here by Faber, must doubtless refer to the
date of the preface placed by him at the beginning of his work; which date is
indicated thus by bim: “Romz e muszo nostro ad Pantheon Agrippz ipsis
Kalend. Januarij Anni solemnis 1625.” From this it appears that Faber, who
had seen Galileo’s Microscopes in May 1624, only became acquainted with those of
the two Germans at the end of the same year.

(16) ‘Atti dell’ Accademia Pontificia de’ nuovi Lincei, pubblicati conforme
alla decisione accademica del 22 dicembre 1850 e compilati dal Segretario T. V.
Anno V (1851-1852)? Roma, 1852, 4to. Ib. pp. 98-140. ‘Ottica. Sulla
invenzione del microscopio. Lettera del prof. D, Luigi Maria Rezzi bibliotecario
corsiniano e accademico linceo onorario al ch. Sig. D. Baldassare de’ Principi
Boncompagni accademico linceo ordinario. Giuntovi una notizia sulle considera-
zioni al Tasso attribute a Galileo Galilei, e sul dubbio se Alessandro Adinari fosse
ono Accademico linceo.’

(17) Venturi (G. Batt.), ‘Memorie e lettere inedite finora o disperse di Galileo
Galilei ordinate ed illustrate con annotazioni ece.’ Modena, 1818, 2 vol. 4to.; vol. i.
pp. 128-9.

(18) Galileo, Opere, t. viii. p. 406.

(19) Omitted.

(20) *L. Annei Senece ad Lucilium, Naturalium questionum libri,’ lib. i. vi.
5 :—‘ Litterze quamyis minute et obscurz, per vitream pilam aqua plenam majores
clarioresque cernuntur. Poma formosiora quam sint videntur, si innatant vitro.”

From different passages, however, of Seneca, and of other ancient writers, one can
easily gather that the enlargement which is here mentioned was by them attributed,
not to the shape of the transparent means (spherical or lenticular, &c.), but to the
density of these media with respect to the air, by which, according to them, the
appearance of objects was increased whatever the shape of the transparent and dense
body through which they were looked at. And it was probably owing to this per-
suasion that the ancients were ignorant of the effects of lenses, or did not know
how to use them.

(21) ‘ Bullettino di Bibliografia e di Storia delle Scienze Matematiche e Fisiche,’
t. iv. (May—June 1871) p. 165. ‘Sur des Instruments d’optique faussement attribués
aux anciens par quelques savants modernes; par Th. Henri Martin, doyen de la
Faculté des Lettres de Rennes, Membre de |’Iustitut.”

(22) ‘C. Suetonii Tranquilli Duodecim Cesares, Nero, Claudius,’ li.

(23) ‘L’ occhiale all occhio, Dioptrica patrica del Co. Carlo Antonio Manzini
dottore Collegiato, ete. Which treats of light, refraction of rays, the eye, vision,
and of the auxiliaries which may be given to the eyes to see the almost impossible.
Where besides are explained the practical rules for making glasses for every sight,
and telescopes with which to examine the planets and the fixed stars on sea, on land,
and others to magnify a thousand times the smallest near object.’ Bologna, 1660,
1 vol. 4to, pp. 98 and following.

(24) Omitted.

(25) ‘ Delle Gemme, notizie raccolte da Augusto Castellani.’ Firenze, 1870, 1 vol.
8vo, p. 208. ‘ Traité complet des pierres prévieuses, etc., par Charles Barbot,’ Paris,
1858, 1 vol. 8vo, p. 320.

(26) ‘ Fratris Rogeri Bacon, ordinis minorum, Opus majus ad Clementem quartum
Pontificem Romanum, ex M8. Codice Dublinensi, cum aliis quibusdam collato,
nune primum edidit 8. Jebb, M.D.’ Londini, 1733, 1 vol. fol. This book was pre-
sented to Clement IV. in 1269. Here are the most important passages relating to
lenses (partis v. part. iii. distine io ii. caput iv. p. 352, lines 23-6 and 31-3) :—

* Si vero homo aspiciat literas et alias res minutas per medium cristalli, vel vitri
vel alterius perspicui suppositi (this must be an ill-read abbreviation, and which must
be read superpositi) literis et sit portio minor sphere, cuius convexitas sit versus
oculum, et oculus in aere, melius videbit literas, et apparebunt ei maiores . . . et ideo
hoe instrumentum est utile senibus et habentibus oculos debiles. Nam literam
quantumcumque parvam possunt videre in sufficienti magnitudine.”

Ibid., Distinct. Ultima, cap. i. p. 357, lines 25-41 :—

“De visione fracta maiora sunt, nam de facili patet per canones supradictos,
quod maxima possunt apparere minima, et e contra, et longe distantia videbuntur

596 SUMMARY OF CURRENT RESEARCHES RELATING TO

propinquissime et e converso. Nam possumus sic figurare perspicua, et taliter ea
ordinare respectu nostri visus et rerum, quod frangentur radii et flectentur quorum-
cumque volverimus ut sub quocumque angulo volverimus videbimus rem prope vel
longe, et sic ex incredibili distantia legerimus literas minutissimas et pulveres ac
arenas numeraverimus propter magnitudinem anguli sub quo videremus, et maxima
corpora de prope vix videremus propter parvitatem anguli sub quo videremus; nam
distantia non facit ad hujusmodi visiones nisi per accidens, sed quantitas anguli. Et
sic posset puer apparere gigas, et unus homo videri mons, et in quacunque quan-
titate, secundum quod possemus hominem videre sub angulo tanto sicut montem, et
prope ut volumus et sic parvus exercitus videretur maximus, et longe positus appa-
reret prope, et e contra; sic etiam faceremus solem et lunam et stellas descendere
secundum apparentiam hic inferius, et similiter super capita inimicorum apparere, et
multa consimilia, ut animus mortalis ignorans veritatem non posset sustinere.”’

(27) ‘Monografia della Vetraria Veneziana e Muranese,’ Venezia, 1874, 1 vol.
8yo. Ibid., parte antica, “ Sulle origini e sullo svolgimento della vetraria Veneziana
e Muranese,” by Bartolomeo Cecchetti, pp. 12 and 13.

(28) TD. Nicolai de Cusa Cardinalis etc. Opera. Basilez, 1565, 1 vol. fol. Ibid.,

. 267.
Poe Liber qui inscribitur de Beryllo incipit. Cap. ii. Beryllus, lapis est lucidus,
albus et transparens cui datur forma, concava pariter et concaya, et per ipsum videns,
attingit prius invisibile.”

(29) Littré, at the word Lunette, in the historical part of his dictionary, quotes
a note of the sixteenth century reported by De la Borde in his work, ‘Sur les Emaux’
(p. 164), and that is the note reported in the text.

(80) ‘Hieronimi Sirturi Mediolanensis Telescopium, sive Ars perficiendi novum
illud Galilei visorium instrumentum ad sydera, in tres partes divisa; quarum
prima exactissimam perspicillorum artem tradit, secunda Telescopii Galilei abso-
lutam constructionem, et artem aperte docet. Tertia alterius Telescopii faciliorem
usum ; et admirandi sui adinventi areanum patefacit. Ad serenissimum Cosimum IT.
magnum Etrurie Ducem. Francofurti, Typis Pauli Jacobi, impensis Lucz Jennis,
1618,’ 4to (82 pp. and 2 pls.). The measures of the lenses indicated in the text are
given by the figure on the large table intercalated after p. 18 in Sirturo’s pamphlet,
and seem derived from the Braccio da panno (yard measure for cloth) of Venice of
683 mm.

(31) ‘Jo. Bapt. Portee Neapolitani Magize Naturalis libri xx. ab ipso Authore
expurgati, et superaucti, in quibus scientiarum naturalium divitize et delitiz
demonstrantur. . . . Neapoli, apud Horatium Salvianum, D.D.LXxxvuu.’ (1589), 4to.

Ib., lib. xvii. cap. X., Xi., Xii., xiii, and cap. xxi. pp. 269-71, and pp. 278-9.

No reference of Porta relating to lenses is to be found in the first edition of the

Porta Neapolitano Autore. Neapoli, apud Matthiam Cancer, M.D.LVIII. cum gratia et
privilegio per decennium.’ 1 vol. fol.

The things written by Porta about lenses in his work, ‘Joan. Paptize Porte
Neap. De refractione optices parte. Libri novem. Ex officina Horatii Salviani.
Neapoli apud Io. Jacobum Carlinum et Antonium Pacem,’ 1 vol. 4to, have no
scientific value whatever.

Ib., lib. viii. pp. 173-88.

(82) Codice Boncompagni: ‘ Lettere di Molti Accademici Lyncei ecc.,’ cart. 354
recto. Letter of Nicolo Antonio Stelliola Lynceo to Prince Cesi, written from Naples
on the 10th of April, 1615 :—

“TJ will not now withhold what happened to me as to my Academic Brother
Gioy. Battista della Porta of holy memory: it is that on visiting him two days before
he took to his bed in this his last illness, he said tome that the enterprise of the
Telescope had killed him; being, as he said, the most difficult and arduous one
which ever he had undertaken.”

Let it be noticed that before the death of Porta, which happened on the 4th
February, 1615, Kepler’s two works had been published: ‘Ad Vitellionem Parali-
pomena’ in 1604, and ‘ Dioptrice’ in 1611, in which the doctrine of lenses and
telescopes was almost completely worked out.

(33) ‘Considerazioni d’ Alimberto Mauri sopra alcuni luoghi del Discorgo di
Lodovico delle Colombe intorno alla stella apparita l’ ottobre dell’anno 1604. In
Firenze appresso Gio. Antonio Caneo, 1606,’ 4to.

(34) ‘Galileo Galilei ed il Dialogo de Acco di Ronchiti da Bruzene, ece. Studi

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 597

e richerche di Antonio Favaro.’ Wenezia, 1881, 8vo. In this pamphlet is at p. 82
a letter of Lodovico delle Colombe, written to Galileo on the 24th June, 1619, which
begins thus :—

“Tt is true that, during the first days after the publication of Mauri’s invective
against me, I suspected on account of certain rumours and conjectures, which
I found afterwards to be groundless, that you had taken part in it with him: but
the excellent Sig. Giov. Battista Amadori assured me from your lordship’s own
words that such was in nowise the case.”

(35) “ Vedi F. Giordano predica del di 23 di Febbraio, 1305.” (This note is by
Mauri himself.)

(36) ‘ Discorso di Lodovico delle Colombe,’ in which he shows that the new star
which appeared in October 1604 in Sagittarius is not a comet, nor a star newly
generated or created, but one of those which were in the heavens from the beginning,
and that this is conformable to true philosophy, theology, and astronomical demon-
gaye In Florence, in the printing office de’ Giunti, 1606, 4to. Ibid., pp. 18,

, and 48,

(37) ‘Annales de Chimie et de Physique,’ 5™° série, t. xv. (1878), pp. 563-73 ;
“De la Mesure du Grossissement dans les Instruments d’Optique, par M. G. Govi.”

(38) Torricelli was the first to give an unhoped-for perfection to the simple
Microscope, by suggesting the substitution of little globes or, as he called them, little
pearls of glass, fused by the enamelling lamp into the very small lenticular glasses,
ee at that time no one had yet begun to work with emery in iron or bronze
moulds,

He sent the news to F. Bonaventura Cavalieri, who, on the 15th of March, 1644,
speaking of the telescope lenses perfected by Torricelli and of these “little pearls”
of his, wrote him thus :—

‘“‘T hear by your letter of the marvellous operation of your glasses, and rejoice
much with you. I see that you wish to leave to none any cause of glory in this most
noble instrument, for with the vigour of your genius you have reached the minimum
and maximum, quod sic, as philosophers say, and you have shown yourself great no
less in the small than in the large parts of such instruments, for I no less admire these
little glass globes, which I understand you have discovered, than this new invention
which I hear you have just made.”

After this letter, Torricelli sent some of his perline to Cavalieri, who thanked him
in a letter of the 5th of April, 1644, showing himself highly satisfied with them.

See ‘ Lezioni Accademiche di Evangelista Torricelli.’ Florence, 1715, 1 vol. 8vo.
In the preface written by Tomaso Bonaventuri, pp. xvii. and xviii,

Father Athanasius Kircher has preserved the record of this invention of Torri-
celli, relating in division ii., paragraph v., cap. viii. of the second part of book x.
of his work, ‘ Ars Magna Lucis et Umbre,’ published whilst Torricelli was still alive
(Rome, 1646, 2 vols. 4to. Ibid., vol. ii. p. $35), that these perline fixed at the
extremity of a small tube were not more than 2:5 or 3 mm. in diameter, and
added : “ Huiusmodi tubulos Serenissimus Joannes Carolus Cardinalis Medicis * non
ita pridem pro singulari suo erga hujusmodi studia affectu, mihi dono dedit; veraque
isto experimento comperi, qu sapientissimus princeps de ijs subinde narrabat.”

(39) ‘Fasti Consolari dell’ Accademia Fiorentina, di Salvino Salvini, Console
della medesima, Rettore generale dello Studio di Firenze. All’ Altezza Reale del
Serenissimo Giov. Gastone, Gran Principe di Toscana.’ Florence, 1717, 1 vol. 4to.

Ibid., pp. 397-432. “ Racconto istorico della vita del Sig. Galileo Galilei, nobil
Fiorentino ece. scritto da Vincenzio Viviani al Serenissimo Principe Leopoldo di
Toscana, il di 29 Aprile, 1654.”

(40) ‘Inedita Galileiana. Frammenti tratti dalla Biblioteca Nazionale di
Firenze pubblicati ed illustrati dal Prof. Antonio Favaro.’ Venezia, 1880, 4to,
pp. 35-43. Extracts from vol. xxi. delle Memorie dell’ Istituto Veneto.

I quote this publication of the Chiarissimo Prof. Favaro rather than Viviani’s
former ones, or Nelli’s, Venturi’s, Alberi’s, or any others, because in this is more
completely and correctly reproduced the text of the inscription engraved by Viviani
on the Cartelloni of his house.

(41) ‘De vero Telescopii Inventore, cum brevi omnium conspiciliorum historia.
Ubi de eorum confectione, ac usu seu de effectibus agitur novaque quedam circa ea
proponuntur. Accessit etiam centuria observationum microscopicarum. Authore

* Giancarlo de’ Medici, son of Cosimo II., born in 1611, made Cardinal in 1644,
died on the 23rd January, 1663.

1889. : 20

598 SUMMARY OF CURRENT RESEAROHES RELATING TO

Petro Borello, Regis Christianissimi consiliario et medico ordinario. Hage Comitum,
mpcuy. 1 vol. 4to.

(42) ‘Nove ccelestium terrestriumque rerum observationes et fortasse hactenus
non vulgate, a Francisco Fontana specillis a se inventis et ad summam perfectionem
perductis, editz. Neapoli, Mense Februarii, mpcxtvti.’ 1 vol. 4to.

(43) ‘Giornale dei Letterati. Roma, appresso li fratelli Pagliarini, 4to, anno
1749, p. 324, 325, 326, anno 1750, pp. 63-4, anno 1751, pp. 94, 95, 254.

(44) Galileo is not named, although his Microscope is described in the two
following works:

‘Teorica degli Stromenti Ottici ecc. di Giovanni Santini.’ Padova, 1828, 2 vols.
8vo, vol. li. p. 174, § 340.

Gehler’s (Johann Samuel Traugott) ‘ Physikalisches Worterbuch, neu _bear-
beitet,’ t. vi. part iii., Leipzig, 1837, 8vo. Ibid., Art. Mikroskop, pp. 2213-14.

(45) ‘Sitzungsberichte der Mathematisch-Naturwissenschaftlichen Classe der
kaiserlichen Akademie der Wissenschaften,’ vi. Band, 1. Heft, 1851. (Wien, 1851,
8vo. Ibid., Sitting of 8th May, 1851, pp. 554-5. See also ‘ Annales de Chimie et de
Physique,’ 3 série, t. xxxv., mai 1852, p. 127.

The President, Dr. Hudson, F.R.S.—At the June Meeting of the
Society, the Fellows congratulated Dr. Hudson on his election as a
Fellow of the Royal Society—a well-deserved honour. The following
is a copy of Dr. Hudson’s Certificate of Recommendation :—“ Charles
Thomas Hudson, M.A., LL.D. (Cantab.), President of the Royal Micro-
scopical Society (1888). Was 15th Wrangler, 1852. Joint author of
Hudson and Gosse’s ‘ Rotifera.’? Discoverer of Pedalion mirum, and of
numerous new genera and species of Rotifera, described in papers
published in the ‘ Journal of the Royal Microscopical Society,’ ‘ Quarterly
Journal of Microscopical Science,’ and the ‘Annals and Magazine of
Natural History,’ from 1869 to the present year. Specially distinguished
for his knowledge of the Rotifera, concerning which he is the chief
living authority.” [‘'The genus Pedalion, discovered and described by
Dr. Hudson, is one of the most remarkable and important contributions
to animal morphology of the past twenty years.” —H. R. L. |

B. Technique.*
(1) Collecting Objects, including Culture Processes.

Cultivation of Bacillus tuberculosis on Potato.t—M. D. Barnsby
confirms Pawlowsky’s experiments on the cultivation of Bacillus tuber-
culosis on potato. The potatoes, sterilized at 100°, were kept in
an incubator at a temperature varying from 88°-40° for ten days.
Precautions were taken that the cultivations should be supplied with
sufficient moisture. The author’s experiments were undertaken for the
purpose of seeking the bacillus in the urine of a child, suspected of
renal tuberculosis. Control experiments were made on Nocard and
Roux’s glycerin-gelose. Positive results were obtained from both media.

(2) Preparing Objects.

New Methods for Preparing Nerve-cells.t—Dr. L. von Thanhoffer
recommends the following methods devised by him for demonstrating
nerve-cells :—

(1) Rapid method.—A small piece of grey substance is pressed

* This subdivision contains (1) Collecting Objects, including Culture Pro-
cesses; (2) Preparing Objects; (3) Cutting, including Imbedding and Microtomes;
(4) Staining and Injecting; (5) Mounting, including slides, preservative fluids, &e. ;
(6) Miscellaneous. t+ Annales de Micrographie, ii. (1889) pp. 362-3.

{ Mathematische und Naturwissensch. Berichte aus Ungarn, vi. (1889) pp. 57-60.

CHARLES T.HUDSON,

M.A., LL.D.(Cantab.),

|e a Se
President of the Royal Microscopical Society,

1888.

isin.

ihe

on
v

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 599

between two cover-glasses, and when these have been drawn apart each
is held over a gas or spirit-lamp flame until the layer of nerve-matter
becomes of a blackish-brown colour, and a distinct smell of burning is
perceived. The preparation is then mounted in xylol balsam or
dammar.

In such preparations the nerve-cells and glia nuclei are seen to be
of a dark-brown colour; the blood-vessels and their nuclei are also
distinctly visible. The glia cells form a delicate reticulum, which
connects the nerve-tubules with the blood-vessels and with the nerve-
cells.

In order to ascertain if the reticulum was produced by a coagulation
of the medullary substance, the fresh layer was soaked in ether for
ten minutes, and the cover-glass then heated. It was found that the
same reticulum appeared, but the cover-glass layer required to be
treated for a longer time. It was afterwards found that if the cover-
glasses were not separated for about one hour the preparations were
more effective.

(2) Double cover-glass preparations.—A piece of grey substance
about the size of a hemp-seed is pressed between two cover-glasses,
between which are placed thin strips of tissue paper. The two cover-
glasses, still sticking together, are then immersed in picrocarmine or in
an aqueous solution of methylen-blue. The preparations required fifteen
days to become perfectly stained. They are then dehydrated in
absolute alcohol (four days), cleared up in oil of cloves, then placed for
two days in xylol, and finally fixed to a slide by pouring some xylol
dammar over them. When the dammar has dried the surface is
cleaned.

Simple Method of freeing Frogs’ Ova.*—Prof. F. Blochmann has
discovered a simple method of freeing the ova of frogs from the
gelatinous matter which surrounds them and from their envelope. A
number of young eggs are preserved in chrom-osmic-acetic acid and
then well washed in water. They are then placed in a shallow glass
with a quantity of eau de Javelle diluted with three or four times its
volume of water; from time to time the glass is shaken. In from a
quarter to half an hour the eggs are quite free. The fluid must then be
carefully drawn off, the eggs washed with water, and concentrated
alcohol be gradually applied; the eggs should be kept in the dark, so
as to remove the remains of the chromic acid. Eggs thus treated, and
then stained with borax-carmine and cut into sections, show no signs of
anyinjury. Prof. Blochmann believes that it will be possible to improve
this method, which he commends to embryologists.

Investigation of Ova of Caprella ferox.t—Madlle. ( Dr.) S. Pereya-
slawzewa found, like M. Mayer, that the chorion covering the egg of
Caprellide offers very great difficulties to the observer; like M, Mayer,
she was tempted to renounce her word. Instead thereof, however, she
devised a plan for detaching the compact chorion. The eggs are placed
in a watch-glass with only sufficient water to keep them moist; boiling
water is poured on them, and the chorion can then be removed with
needles. The ova are then placed for from three to five hours in weak
spirit, and then in absolute alcohol for twelve hours. Eggs prepared in

* Zool. Anzeig., xii. (1889) pp. 269-70.
+ Bull. Soc. Imp. Nat. Moscou, 1888 (1889) pp. 582-3.
27 2

600 SUMMARY OF CURRENT RESEARCHES RELATING TO

this way stain perfectly well; borax-carmine is to be preferred as a
staining agent. If imbedded in paraffin they give excellent sections.

Preparing and Mounting Insects in Balsam.*—As it is difficult
in preparing many of the smaller forms of insects to remove the
débris from the surface of the specimen without injuring the delicate
portions, Mr.-Leckenby uses albumen, flowing the white of an egg
over the object and immersing the slide in hot water till the albumen is
coagulated, when it will generally crack open, and may be removed in
two portions, carrying with it all the foreign matter and leaving the
surface of the specimen perfectly clean. He strongly advocates thorough
washing of the objects in running water and a final rinsing in either
filtered or distilled water before placing in alcohol.

In mounting, the insect is placed under the cover-glass, arranged in
proper shape, the clearing solution applied, and when sufficiently trans-
parent the oil of cloves is cleared away and Canada balsam introduced
at one edge of the cover-glass, the slide being held over the flame of a
lamp to gently warm the balsam and allow it to flow in and displace the
remaining oil of cloves. No annoyance need be felt at the presence of
bubbles of air, as they will all gradually disappear. The mount, when
filled with balsam, is placed in a warm oven or incubator and kept at a
temperature of from 120° to 130° F. for twenty-four hours, when the
balsam will be thoroughly hardened and all the air-bubbles driven out.

Mr. Leckenby does not advocate the use of volatile solvents with
balsam, being convinced that a certain amount of gas is always retained
in the mount in a latent state, requiring only a slight amount of heat to
produce bubbles and disfigure the specimen.

Demonstration of Embryo-sac.j—Prof. D. H. Campbell recom-
mends Monotropa uniflora for this purpose, in consequence of the com-
paratively large size of the ovules and embryo-sac. It is only necessary
to strip away a small piece of the placenta with the adherent ovules, and
mount in water or a 3 per cent. solution of sugar. In the latter fluid
the ovules remain unchanged for several hours, and may be studied at
leisure. The embryo-sac is covered by only two layers or cells, and
these are perfectly colourless, not interfering in the slightest degree
with the view of the embryo-sac.

Demonstration of Pollen-mother-cells and Pollen-tubes.{—Prof.
B. D. Halsted recommends for this purpose the young anthers of
Negundo aceroides. A section of the anther-lobe will be found to be
made up of a single ring of mother-cells, many of which are pear-
shaped; and in these loose cells the four pollen-grains may be found in
all stages of development. At first there is only the slightest differen-
tiation of the protoplasm into four indistinct masses, which gradually
become more evident, their arrangement in the mother-cell varying.
‘Azorubin is excellent in weak solution for bringing out the young
grains more prominently.

For the observation of the emission of pollen-tubes, the same writer §
places pollen-grains in a solution of sugar varying between 10 and
75 per cent. Species of Asclepias, for which the most favourable strength

* Proc. San Francisco Micr. Soc., April 24th, 1889.
+ Bot. Gazette, xiv. (1889) p. 83 (1 fig.). t Tac. p; 109!
§ Bull. Torrey Bot. Club, xvi. (1889) pp. 130-1.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 601

is 65 per cent., are well-suited for the purpose. The pollen-grains of
Tradescantia virginica will produce tubes 100 long in two hours.

Continuity of Protoplasm in Plants.*—Mr. J. M. Coulter finds the
cortex of the “ buck-eye” (Aifsculus Pavia) to be a favourable object for
demonstrating the continuity of protoplasm. The strands which connect
the protoplasts are here so large that they may be satisfactorily seen
with a magnification of 250, and very well studied with one of 500 dia-
meters, and in neither case is there any necessity for using an immersion
objective. Mr. Coulter carefully slices the periderm from a twig about
1/4 to 1/2 in. in diameter, so as to expose the cortex; then makes a thin
tangential section from the latter, and immerses in a solution of iodine
in potassium iodide until it turns brown, washes to remove the excess of
iodine, and mounts in water; at the edge of the cover-glass is then
placed a drop of pure and two drops of 75 per cent. sulphuric acid;
after this has been drawn under, the section is very thoroughly washed,
and the water replaced by glycerin. Even a low power will now show
the very much swollen and transparent walls crossed in every direction
by protoplasmic strands connecting the contracted brown protoplasts.
To make a permanent mount, it will be necessvry to use some stain for
the protoplasts and their connecting strands; otherwise the strands
gradually become so transparent in the glycerin as to be almost invisible.

(4) Staining and Injecting.

Staining reagents for Wood.{—Dr. E. Nickel adduces reasons for
the?view that the so-called lignin-reaction of woody tissue is not due to
the presence of a definite chemical compound, but to the aldehyde-con-
stituents of the wood.

Staining of sections to show Micro-organisms in situ.t—Dr. H.
Kuhne opines that it is a mistake to use strong solutions of dyes to
show the presence and position of micro-organisms in sections of animal
tissue, as the differentiation is very difficult to bring off, owing to the
compulsory use of decolorizing agents. He advises the employment of
weak solutions, so that the tissues are not overstained, and to differ-
entiate with acid or basic anilins.

The author states that he has given up the use of alcohol as a dehy-
drating agent, and uses only anilin oil for this purpose. In demon-
strating the presence of bacteria in tissues, he first used anilins, basic
and acid, dissolved in oil of cloves. This last reagent he has now dis-
carded altogether in favour of anilin oil, which medium he now employs
universally, i.e. stained or unstained, accoiding as it is desired to use
it as an extracting agent, a dehydrant, or for the purpose of double
staining.

New and rapid method of staining the capsule of Bacillus pneu-
moniz. §—Dr. U. Gabbi employs the following method for staining the
capsule of Bacillus Pneumonie Frenkel. The sputum to be examined
is spread on a cover-glass and quickly dried in a spirit-lamp flame.
Two or three drops of a solution of 2°5 gr. carbolic acid, 1 gr. fuchsin,
and 15 gr. alcohol in 100 gr. distilled water, are then dropped on the

* Bot. Gazette, xiv. (1889) pp. 82-3 (1 fiz.).

+ Bot. Centralbl., xxxviii, (1889) pp. 753-6.

t{ Annales de Micrographie, ii. (1889) pp. 358-61.
§ La Riforma Medica, 1889, No. 31.

602 SUMMARY OF CURRENT RESEARCHES RELATING TO

preparation, where they are allowed to remain for one minute. It is
then quickly washed in water, and in preparations thus treated the
bacillus is stained dark red and its capsule bright red. The staining of
the capsule vanishes if left too long in water.

Staining Tubercle Bacilli on Slides.*—The slide-method, says Dr.
Schill, offers several advantages over the cover-glass method for staining
bacilli. On account of its larger surface, larger areas of the same or of two
to four different kinds of sputum can be simultaneously stained, decolor-
ized, and after-stained. For examining the same sputum, only one cover-
glass is needed, and this, when the first part of the sputum has been
gone over, is pushed down the slide about the distance of the breadth of
the cover by just running a droplet of water on to the edge of the cover-
glass. In examining different sputa upon the same slide, the cover-glass
is withdrawn after each examination, and wiped carefully before being
placed upon the second sputum, &c. If a permanent preparation of the
sputum is not required, the cover-glass should be cleaned in spirit
directly the examination is over. Slides covered with sputum can be
kept even without a cover-glass, if protected from dust, and are labelled.
If repeated examination be required, a permanent preparation is made,
or the slide made be examined anew with the cover-glass and drop of
water. Owing to the greater thickness of the glass, heat is given off
much more slowly after the slide has been drawn thrice through the
flame. Hence the Ziehl-Neelsen solution need not be warmed if the
staining solution be dropped on the slide while it is still hot.

With this method, nine or ten colonies from a plate cultivation can
be examined at the same time.

(5) Mounting, including Slides, Preservative Fluids, &c.

New Medium for Mounting Pollens and Starches.;—Mr. A. P.
Brown writes, that having experimented with all the various media
recommended for the purpose, he has finally adopted the following for
permanent mounts of pollens and starches :—R Selected gum arabic, 2 02.;
glycerin, distilled water, each 13 fl. oz.; thymol, 1 gr. These are all
placed in a wide-mouthed bottle, which is corked carefully to exclude dust,
and placed in a warm situation. It takes several days to effect a perfect
solution, the mixture being stirred up occasionally. When all is dis-
solved, strain through linen, and set aside the liquid about a week
longer to get rid of air-bubbles, and to allow any small particles that
may have passed through the strainer to settle to the bottom; or it can
be filtered through absorbent cotton by using a funnel for hot filtration,
which consists of a double tin case holding water, kept at the required
temperature by a spirit-lamp placed under the projecting arm. A glass
funnel fits inside the hot water-bath, a plug of absorbent cotton is
placed in the funnel, and the solution is passed through it. After
filtration it is best preserved in compressible tubes. ‘The medium is the
suggestion of M. Charles Bulloch, the well-known Chicago optician
and microscopist.

Rest for Slides and for Cultivation Plates.{—M. L. Malassez makes
his rest for slides entirely of metal. It consists of two uprights united

* Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) p. 340.
+ St. Louis Med. and Surg. Journ., lvi. (1889) pp. 288-9, from ‘ American
Journal of Pharmacy,’ J Arch. de Physiol., viii. (1886) pp. 275-7 (1 fig.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. €03

by two transverse pieces, and from the uprights proceed outwards in
opposite directions two branches of which there are several tiers. At
the end of each branch is a stop to prevent the slides from slipping off.
The distance between the branches is such that the ends of the slides
only just rest on them so that there is no fear of spoiling the preparations.

Rests of larger dimensions are made for special cultivations. For
this purpose the plates or slides are hollowed out on their upper surface
to prevent the nutritive medium from running off when liquefied by heat
or micro-organisms. These slides are 10 cm. long and 5 em. broad, and
therefore can be examined with ordinary Microscopes without being
obliged to be turned round. Both rests are intended to be covered over
with a bell-jar.

Nitric Acid in Gelatin.*—Dr. R. J. Petri, who recently showed the
presence of nitric acid and other adulterations in gelatin, now communi-
cates the cause of its presence. It appears that caustic lime is used in
the manufacture in order to get rid, by means of saponification, of any
fatty matters. The excess of lime is then removed by means of water.
But as a considerable quantity of lime still remains behind, this is
neutralized with nitric acid. Hence the presence of nitrates and of lime.

(6) Miscellaneous.

Rosenbusch’s Petrographical Tables, an aid to the Microscopical
Determination of Rock-forming Minerals.—This is a translation,t by
Dr. F. H. Hatch, of Prof. H. Rosenbusch’s ‘ Hiilfstabellen zur mikroskop-
ischen Mineralbestimmung in Gesteinen.’

These useful tables contain, in handy form, convenient for reference,
the most important physical and chemical properties of the principal
rock-forming minerals. They constitute, in fact, a summary of the
contents of the first volume of Prof. Rosenbusch’s ‘ Mikroskopische
Physiographie.’

The tables are arranged under three main divisions, viz. Table I.,
singly-refracting minerals; Table II., containing two subdivisions a and
b; doubly-refracting uniaxial minerals; Table II!., containing six
subdivisions a—/, doubly-refracting biaxial minerals.

The several headings of the parallel columns forming each table are
as follows :—Name of mineral ; crystallographic system ; cleavage under
the three divisions of quality, direction, and angle; characteristic form;
optical character (++ or —); principal zone or face ; forms and optical
character of principal zone; colour ; pleochroism ; index of refraction (n)
at+B+y

3

and double refraction under the four divisions n = ,y— 4,

8 — a,y — f; optic orientation ; apparent optic axial angle; dispersion ;
specific gravity ; behaviour with reagents; chemical composition ;
remarks,

New Method of Determining the Number of Micro-organisms in
Air.{—This new process, which was devised by Prof. T. Carnelly and
Mr. T. Wilson, is a modification of Hesse’s method, in which a flask is

* Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) pp. 679-80.

+ 4to, London (Swan Sonnenschein & Co.) n. d., 3 tables and preface. Cf.
Nature, xl. (1889) pp. 313-4.

‘t Proc. Roy. Soc. Lond., xliv. (1888) pp. 455-64 (1 fig.).

604 SUMMARY OF CURRENT RESEARCHES RELATING TO

substituted for a tube. The flask is conical, and holds about half a litre,
and is fitted with a two-holed indiarubber stopper. ‘Through one hole
passes the “entrance tube” AA, a glass tube about 8 in. long, and
haying an internal diameter of 3/8 in. It reaches about two-thirds of
the way down the flask, and is closed at
Fic. 70. the outer end by a glass stopper B fitted
on with a piece of indiarubber tubing.
Into the other hole of the stopper is
fitted the “exit tube” CC. This is a
piece of glass tubing (1/4 in. diameter)
bent round at the lower end, so that it
opens in the neck of the flask just under
the rubber stopper. It is open at both
ends, but contains two cotton-wool plugs
to prevent entrance of any micro-organ-
isms from the outside.

Ten ccm. of Koch’s pepton-gelatin
are introduced into the flask, and the
stopper tied on with copper wire. The
flask is then steamed for an hour at
100° C., and on cooling, an even layer
of gelatin is distributed over the bottom. _

In taking a sample of air the aspi-
rator is attached to the exit tube C, and
the rubber tube and stopper B removed
from A. <A known volume of air is then
drawn through the flask, after which the
stopper is replaced. The microbes settle
on the jelly, and having developed into
colonies, may be counted in a few days.
Counting may be facilitated by marking
out the bottom of the flask in squares. The rate of aspiration adopted
was 1 litre in three minutes. In order to prove the safety and certainty
of this method, various tests, for which the original must be consulted,
were applied.

The authors consider that their method is extremely safe, and
possesses all the advantages and none of the disadvantages of Hesse’s and
Frankland’s methods.

Value of Bacteriological Examination for Estimating the Purity
of Drinking-Water.*—In a short review of the present condition of
the question as to how far the bacteriological examination of water is of
value in estimating its purity, Dr. Ordmann sums up very shortly the
results of his own and others’ experiments. It may be remembered that
when plate cultivations were first used for the breeding of micro-
organisms, much was expected of this method for determining the
quality and characters of micro-organisms present in a given specimen
of water. This expectation was not fulfilled, for it was found on the
one hand, in water chemically good, that not unfrequently there were
large quantities of micro-organisms present; and on the other, that in
water chemically bad, it very frequently happened that but few micro-
organisms developed. So that the author, while not depreciating the ~

* Zeilschr. f. Naturwiss., Ixi. (1888) pp. 654-8.

ZOOLOGY AND BOTANY, MIOROSOOPY, ETO. 605

value ofa bacteriological examination of drinking-water, concludes that it
is not safe to rely on it asa practical test both for the reasons given above,
and also because the presence of micro-organisms is no test of impurity,
since it is the opinion of some observers that many of these microbes
are normal constituents of drinking-water. Much, too, is to be said
against laying too much stress on the pathogenic character of the
organisms when they are found to liquefy gelatin.

Apparatus for the Bacteriological Examination of Water.*—In
order to distribute with regularity all the germs present in a specimen
of water on the gelatin plate, and at the same time to be able to
distinguish these from aerial impurities, M. Arloing has devised a
complicated “analyser.” A rectangular copper box, 250 cm. long,
85 cm. broad, and 36 cm. high, is so far closed on the short sides
by two glass lids, movable on hinges, that there remains between them
a space 7 cm. broad. The interspace can be closed by means of a
piece of metal with a hole in the middle. To one of the small sides igs
fixed a support, on which a pipette is fixed, so that it can hang vertically
down through the interspace passing through the aperture in the metal
plate. The support, and with it the pipette, is able to be moved in the
direction of the cleft by means of a screw arrangement. On the bottom
of the box is a strip of brass for the reception of a glass plate, and
which also by means of a screw is movable in the long axis of the box.
The glass plates intended for the gelatin have raised edges, are
12 cm. long, 5 cm. broad, and divided into 60 squares of 1 sq. cm. each.

When water is to be tested, a gelatin plate is introduced, and the
pipette filled with water to be examined. The latter is then allowed to
fall drop-wise on the gelatin plate, so that every square space receives
one drop. The plate is then removed to an incubator.

The advantages claimed for this apparatus are that the water is
distributed regularly all over the plate, and that germs from the air are
excluded.

Chemical and Bacteriological Examination of Water.t—Drs. F.
Tiemann and A. Gartner have just issued the third edition of Kubel-
Tiemann’s ‘ Introduction to the Examination of Water.’ The present
edition, which has been enlarged and thoroughly revised, is illustrated
with many wood engravings, and ten chromolithographic plates. The
work is divided into three parts. The first of these, for which Tiemann
is responsible, is devoted to chemical examination ; the second, which
is the work of Gartner, deals with the microscopical and bacteriological
examination of water; while the third part, which is the joint work of
both authors, sums up the results of the chemical and bacteriological
experiences.

The book seems to have had considerable care bestowed upon it, and
is rich in details which are useful to various classes of students interested
in the conditions of water as considered from their different standpoints.
Thus the chemist, the physician, and the trader obviously regard water
in different lights, and these and other classes will find their requirements
attended to in this work.

Diagrams of Microscopical Objects for Class Teaching.t—Dr. L.
Klein in a long article states that he has derived much advantage from

* Revue d’Hygiene, x. (1888) No. 6. + 8vo, Braunschweig, 1889.
¢ Zeitschr. f. Wiss. Mikr., vi. (1889) pp. 18-32.

606 SUMMARY OF OURRENT RESEARCHES RELATING TO

the use of diagrams of microscopical objects for class teaching. These.
diagrams are made in the usual manner with chalks, charcoal, and pig-
ments. The only novelty in the paper is the suggestion that time may
be saved by obtaining the image of an illustration in a book by placing
the leaf in a magic lantern and throwing the image on the drawing
paper.

Thallin, a new reagent for Lignin.*—The otherwise excellent re-
agent for lignin, phloroglucin, has the disadvantage that the stained
preparations rapidly become colourless on exposure to light. Herr R.
Hegler proposes as a substitute thallin, which is an extraordinarily
delicate reagent for lignified tissue, is of very easy application and
great persistence under the action of light, and possesses the additional
advantage of presenting no reaction with coniferin. The section is
placed first in pure alcohol, and then, in a watch-glass, in a concen-
trated solution of thallin-sulphate in dilute alcohol; all the lignified
parts then assume a dark orange-yellow colour, which increases with the
length of the immersion, and is not lost after exposure to the light for
months, while the cellulose and cork membranes remain perfectly
colourless. With long immersion the cellulose and cork tissues assume a
slight rose colour. 1 ccm. of a 1 per cent. solution, containing 0-001 gr.
of thallin-sulphate, produces a strong reaction with pine-wood ; and this
is by no means the limit of the sensitiveness. With regard to the
reaction of the various lignin-reagents on the two substances which are
the constant associates of lignified tissues, vanillin and coniferin,—thallin
reacts with vanillin but not with coniferin, phenol-hydrochloric acid
with coniferin but not with vanillin, all the other lignin-reagents with
both.

New micro-chemical reagent for Tannin.t—According to M. L.
Braemer there are objections to all the reagents at present used for the
detection of tannin; ammonium molybdate has the disadvantage that its
precipitates with tannic acid are soluble in water and dilute acids, and
the reagent itself has but little persistency. The author proposes as a
substitute a mixture of 1 gr. sodium tungstate and 2 gr. sodium acetate
in about 10 ccm. of distilled water, which precipitates both tannic and
gallic acid, but cannot be used to distinguish between these two. It
does not precipitate albuminoids, nor other substances resembling tannin.
By this reagent the presence of 0:00001 gr. of gallic acid can be detected.

Tests for Tannin.t—In the account of his researches on the presence
and distribution of tannin in the vegetable kingdom,§ Herr H. Moeller
thus classifies and comments on the various chemical tests used for this
substance.

(1) Iron-salts.—The great objection to the use of these reagents is
that the compounds of iron and tannic acid are readily soluble in excess
of the reagent, in weak acids, or in alkaline liquids. The last the author
has observed only in the case of Tussilago Farfara, while in many cases
tho compounds in question are soluble in acids, especially in hydro-

* SB. Bot. Ver. Miinchen, March 11, 1889. See Bot. Centralbl., xxxviii. (1889)
p- 616. ;

+ Bull. Soc. Hist. Nat. Toulouse, 1889, Jan. 23, 4 pp. See Bot. Centralbl.,
XXXvViii. (1889) p. 820.

t Ber. Deutsch. Bot, Gesell., vi. (1889) Gen.-Versaimml.-Heft, pp. Ixvii.—lxxi.

§ Cf. ante, p. 541.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 607

chloric acid. Chloride of iron exhibits osmose freely in a dilute
aqueous solution, but always has an acid reaction; when dry and dis-
solved in absolute ether, it is an exceedingly good reagent for tannin.
Acetate of iron in the form of either liquor ferri acetict or tinctura
ferri acetict gives a beautiful reaction; the former diffuses with great
difficulty ; the latter is preferable in many respects. Citric iron-
ammonium oxide can only be used in a few cases, in consequence of its
very slight diffusibility.

(2) Of oxidizing reagents, potassium bichromate gives a beautiful
chestnut-brown precipitate. Its comparatively slight diffusibility can be
increased by the addition of a few drops of acetic acid. It is probable
that one product of the oxidation of tannin is purpuro-gallin or an allied
substance, but the author believes that there are several kinds of purpuro-
gallin, and that these result from the oxidation of different tannin acids
in the plant. Ammonium molybdate (Gardiner’s reagent) is the one
recommended by the author as the best. It may be slightly alkalized
by ammonia in order to increase its diffusibility ; and the remaining cell-
contents are then for the most part left unchanged. Dilute aqueous
solutions of alkalies oxidize indirectly by the production of oxygen; but
these reagents cannot be recommended, neither can the reaction with
iodine.

New method of recognizing small quantities of Invertin.*—Accord-
ing to M. J. Costantin, Bacillus phosphorescens Hermes (Micrococcus
phosphorescens Cohn, M. Pfliigert Ludwig), which is found on salt fish,
possesses a phosphorescent property when it developes in glucose, but it
loses this in the presence of saccharose. This property serves to detect
invertin in small quantities. A decoction of the fish in sea-water is
prepared, and 7 per cent. of gelatin added, which is mixed with the
culture of the above mentioned bacillus. After coagulation there
remains a luminous substratum ; this, at the end of two or three days,
shows great sensitiveness towards chemical agents. If saccharose be
added to the gelatin, the luminosity does not change; but if a trace
of invertin be added, it quickly forms a large luminous plate on the
substratum.

* « J.C.” in Morot’s Journ. de Bot., iii. (1889) p. 32.

a © 608; )

PROCEEDINGS OF THE SOCIETY.

Meeting oF 121TH June, 1889, at Kine’s Cotteer, Stranp, W.C.,
tHE Preswpent (Dr. CO. T. Hupsoy, F.R.S.) In tHE Cuatr.

The Minutes of the meeting of 12th May last were read and con-
firmed, 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.

Rosenbusch, H., Petrographical Tables. An Aid to the Micro- From

scopical Determination of Rock-forming Minerals. Trans-

lated and edited by Dr. F. H. Hatch. 3 tables and preface.

(4t0, London, n.d.) Swan Sonnenschein & Co. .. .. .. The Publishers.
Slides (2), Megalotrocha semibullata . « o Mr, V. Gunson Thorpe, Surg. R.N.
Slides (2), Asplanchna n. sp. and Lacinularia n. sp. o- «» «o Mr. T. Whitelegge.

The President said that the Fellows were aware of the necessity
which had arisen of finding rooms for the Society in consequence of
their having to vacate those at present in occupation at King’s College,
and he called upon the Secretary to make a statement as to the steps
which had been taken by the Council in the matter.

Mr. Crisp said that, after some deliberation, the Council had decided
upon taking rooms which had been offered to them at No. 20, Hanover
Square. The house had been taken by the Medical and Chirurgical
Society who intended to occupy the ground-floor and lct off the rest to
other Societies. The portions available were the first and second floors,
with the use of a large meeting room which was to be built upon the
garden at the back. They were not able to afford the rent asked for the
first floor, and had therefore decided to take two rooms on the second floor
—at the back, these being larger than the front. They were to have a
lease of these for 21 years, and the rent was agreed at 1301. per annum,
which sum would include cleaning, rates and taxes, and electric lighting.
This rent was rather more than they were paying at the present time,
but considering the difficulty of getting suitable accommodation, he
thought the Fellows would have every reason to be satisfied, especially
as the increased expense would only be about 20/., and this would
be met by the addition to their income from new Fellows during the
year. They were not obliged to turn out of their present premises
before next year, and as it would take some time to get the new ones
ready, they would probably hold another annual meeting where they
were.

Mr. Crisp called attention to a new homogeneous-immersion 1/12 in.
objective by Messrs. Powell and Lealand, under which Mr. Powell was
showing Amphipleura pellucida in a very satisfactory way. He must not
say anything as to the price, but those who knew what it was might be
tempted to conclude that they had been paying rather too much for that
class of objective hitherto.

PROCEEDINGS OF THE SOCIETY. 609

Mr. C. L. Curties exhibited a new 1/2 in. apochromatic objective by
Zeiss, with a numerical aperture of 0°60. This was only the second of
its kind which had reached this country, the other being in the hands
of Mr. Nelson, who spoke very highly in praise of its performance. It
was shown with an achromatic condenser designed by Prof. Abbe, who,
he believed had been converted to adopting achromatism in the
illuminator.

Mr. J. Mayall, junr., said that it was upon the occasion of his visit
to Jena that he brought the attention of Prof. Abbe to bear upon the
subject of the achromatic condenser, and having shown him the advantage
obtained by its use he was in the end convinced of its value. The
instrument used by Mr. Curties was an embodiment of the idea then dis-
cussed by Prof. Abbe, the first ones made being intended for use in photo-
micrography. It had an aperture very close upon unity, so that it had
the maximum required for dry lenses. There was also an arrange-
ment by which if it was required for use with other powers the front
combination could be removed, and a larger field by that means obtained.
There was one point in connection with the use of these condensers,
which it seemed, from the work sometimes exhibited, needed to be rather
plainly dwelt upon: this was that the light should always be accurately
focused upon the plane of the object, otherwise the best results could
not be obtained. There were, as they knew, both thin plates and thick
plates upon which objects were mounted, and when an achromatic
condenser was made for use with a thin plate, it was unfair to use it
upon a thick one; the proper thickness must be considered if the best
effect was desired, and it was very important, therefore, to note that the
focusing should be accurately centered upon the plane of the object.
The thickness could be altered, sometimes, by turning the slide over, or
by putting additional pieces of thin glass temporarily above or below.
Some manipulators had adopted that plan, but others did not seem sufii-
ciently aware that the object was to give a very perfect image of the
lamp-flame.

The President inquired whether these new condensers had a large
head, or were coned down.

Mr. Mayall said that with so large an aperture as N.A. 1, the
condenser had to come up almost in contact, and being designed to work
with both medium and high powers the lenses had to be of large size.

The President thought it would in this way be only applicable to
mounted objects, and not to live ones, especially as they wanted some-
times to reverse them.

Mr. Mayall thought this would apply to all condensers, but would
depend upon the lenses in some degree. They had been very successful
in Jena in obtaining long working distances for their objectives, one of
1/8 in. used by Dr. Dallinger had two or three times the working
distance of those ordinarily made. This was due, no doubt, to the new
glass, and also to the great care taken in the coning of the lenses as
they lay one above the other.

Mr. Western exhibited a species of Asplanchna, which, he said, the
President had been good enough to identify for him.

The President said that when Mr. Western showed him these
specimens he recognized them at once as old friends from America, like

610 PROCEEDINGS OF THE SOCIETY.

some which had been sent to him in spirit. On first seeing them he
thought they were Hbbesbornii, but the posterior end was more pointed,
and the male had only two lateral humps, and not two under the neck
as Ebbesbornii. In many respects Asplanchna was very perplexing and
it seemed as if the males varied at different periods. He called atten-
tion to some rotifers exhibited by Mr. Rousselet with exceptionally good
dark-ground illumination and inquired how it was obtained.
Mr. Rousselet said it was done with Abbe’s ordinary condenser.

Mr. Crisp read a letter with reference to some lithographic drawings
of microscopical objects made by a young lady, Miss C. HE. H. Abrahall.
The prints were handed round for inspection and were much approved.

Prof.§. P. Thompson’s paper, “ Note on Polarizing Apparatus for
the Microscope ” was read (post).

Surgeon V. Gunson Thorpe, R.N., read his paper, “ Description of a
new species of Megalotrocha” from Brisbane (post).

The President felt sure that the Fellows of the Society would be
very much indebted to Surgeon Gunson Thorpe for bringing this subject
before them. He had himself had the pleasure of corresponding with
him upon these matters, and had been much struck by his power of
observation and the skill which he had displayed in drawing what he
had seen. The animal which had been described was not only new, but
was remarkable in many points. It was found to be a swimming
creature, but he doubted whether it was permanently so, because he
thought the size seemed to indicate that it was a young form, and he
had seen instances where a number of them, though quite free, would
turn their tails together and form a cluster very much like Conochilus.
He had never seen so large a cluster as seventy, described by Mr.
Thorpe.

Mr. Thorpe said he had found one species which was much larger.

The President thought that the two animals differed in one or two
points—first, in Megalotrocha, the squarish form of the corona was
peculiar and as distinct as that of Melicerta tubicolaria ; then the two
knobs were not found in the same place, the eyes were also remarkable,
and the trifid stem was also curious, like a club with three knobs. In
albo-flavicans there was seen a remarkable habit of all the members of
a group sweeping down together just as if a wave passed along them; in
that motion the whole of the foot took part. It had also been noticed
that when contracted the knobs or warts were always found at the top
of the contracted part—that might be the use of them, so that they
might protect from injury, something in the same way as the bosses
upon a trunk. Unfortunately all these points were lost in the slide
which Mr. Thorpe had brought with him, showing how necessary it was
to see these things alive if they wished properly to understand them.
There was also a slide exhibited in the room of Lacinularia pedunculata,
showing the long stem very plainly. He had with him some small
tubes containing specimens of this creature for distribution to those
Fellows of the Society who were interested in the study.

PROCEEDINGS OF THE SOCIETY. 611

Mr. Gunson Thorpe also called attention to a curious organism which
he had found upon the surface of the sea, surrounded by a mass of
sponge spicules and shells made into a kind of nest ; its movement was
rather slow, but it swam about quite freely.

The President thought it very curious ; it appeared to be some kind
of marine worm, something like the Caddis.

Prof. Bell said it was one of the most interesting marine objects he
had seen lately, but he had not the faintest idea what it was, neither had
he been able to find out anything about it from the sources of informa-
tion which he had consulted. Mr. Thorpe had a number of drawings,
and it might be worth while to insert a woodcut of this object in the
Journal in the hope that some one seeing it might be able to give some
information about it.

The President said he had brought to the meeting a somewhat
rough model for the purpose of giving a true notion of what the head of
a Conochilus was like. Most people knew the object very well, but
many descriptions given—especially foreign ones—gave very misleading
ideas of the structure. This he thought was perhaps mainly due to the
use of one tube and the examination of the object by transmitted light by
persons who did not know what the thing was, and had therefore
resorted to the process of guessing what it was by focusing up and
down upon it. When a man described a closed surface as an open one,
and said there was one row of cilia when there were really two rows, it
was clear that the object was not understood. Unless it was properly
examined, it was a very difficult object to make out, and hence the
mistakes made. The model was passed round for examination.

Mr. J. D. Hardy said it struck him as being somewhat different in
form from what his own observations led him to suppose was the case.
The opaque objects were for instance more upon the disc than appeared
in his own drawings.

The President said he could answer for certainty that they were
as shown on the model on the neck and shoulders—generally they were
only seen through other portions.

Mr. Hardy could quite corroborate the statement as to the difficulty
there was in drawing Conochilus.

Mr. Crisp said he was sure the Fellows would be glad to congratulate
the President upon his recent election as a Fellow of the Royal Society.
His qualifications as set out upon the certificate would perhaps interest
the Fellows present, and he therefore read them to the meeting.

The President said that he thanked the Society very much for the
manner in which they had received Mr. Crisp’s very kind remarks.

The President said they were favoured that evening by the presence
at the meeting, as a visitor, of Mr. J. Ferrier, ex-President of the
Microscopical Society of Montreal.

Mr. Ferrier said it had given him great pleasure to be present at the
meeting. Their Society in Montreal was not a very large one, haying
been originally formed as a club of twelve members, each of whom was
privileged to bring three friends to the meetings. Dr. Carmichael was
the President of the Society at the present time. He felt very much

612 PROCEEDINGS OF THE SOCIETY.

obliged to the Fellows for the kind reception they had given to him as
a visitor from a kindred Society in a distant city.

Mr. E. M. Nelson’s paper on “‘ A means for the detection of Spurious
Diffraction Images” was read.

Mr. T. F. Smith said he should like to have some demonstration
from Mr. Nelson as to the doubling of the width of the grating, because
he “held that if an object was delineated at all it was delineated
correctly.”

The President said there remained to him now only the pleasant
task of wishing the Fellows of the Society a very happy vacation, ex-
pressing at the same time a hope that they would be able to bring
something back with them of interest to future meetings.

The following Instruments, Objects, &c., were exhibited :—

Miss Abrahall :—Lithographic Drawings of microscopic objects.

Mr. C. L. Curties:—1/2 in. Apochromatic Objective by Zeiss, and
Abbe Achromatic Condenser.

Dr. C. T. Hudson :—Model of Conochilus.

Mr. T. Powell:—1/12 in. Hom. Imm. Objective.

Mr. Gunson Thorpe :—Two Slides of Megalotrocha semibullata.

Mr. Western :—Slide of Asplanchna n. sp.

Mr. T. Whitelegge:—Slides of Asplanchna n.sp. and Lacinularia
n.sp., and an unknown organism.

New Fellows:—The following were elected Ordinary Fellows :—
Messrs. John Goodfellow, B. M. Winder, F.C.S., and Thomas White-

legge.

The Journal is issued on the second Wednesday of
February, April, June, August, October, and December.

: ee
¢ “1
1889. Part 5. OCTOBER. {reineba st 8

JOURNAL

OF THE

ROYAL :
MICROSCOPICAL SOCIETY:

CONTAINING ITS. TRANSACTIONS AND PROCEEDINGS,

AND A SUMMARY OF CURRENT RESEARCHES RELATING TO
ZOOLOGY AND BOTAN T
(principally Invertebrata and Cryptogamia),
MICROSCOPY, Sc:

Edited by

FRANK CRISP, LL.B., B.A.
One of the Secretaries of the Soctety
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., BSc., F.LS., F. JEFFREY BELL, M.A., F.ZS.,
Lecturer on Botany at St. Thomas's Hospital, Professor of Comparative Anatomy in King’s College,
JOHN MAYALL, Jon., F-ZS., R. G. HEBB, M.A., M.D. (Cantab.),
: AND
.. J. ARTHUR THOMSON, M.A,,
Lecturer on Zoology in the School of Medicine, Edinburgh,
FELLOWS OF THE SOCIETY.

KIWILLIAMS .& NORGATE.
LONDON AND EDINBURGH.

’

PRINTED BY WM. CLOWES AND SONS, LIMITED,] {STAMFORD STREET AND CHARING CROSS.

ite

NOTE. — Plate X. issued herewith is in substitution for that issaak with the ee

craic No., the age of which are incorrectly numbered.

CONTENTS,

SUMMARY OF CURRENT RESEARCHES, ETC.
MICROSCOPY —continued from August No, :

Tur Preswent, Dr. Hupson, FYR.S. 2.0 22 ee es ae we tte ne

_ &p. Technique.

() Collecting Objects, including Culture Processes.
Barnssy, D.—Cultivation of Bacillus tuberculosis on oe so eee we

(2) Preparing Objects: *
THANHOFFER, VON L.—New Methods for Preparing Nerve- Cells atUniey ee

Buocumann, F.—Simple Method of Freeing Frogs’ Ova... +2 ae ae we
PEREYASLAWZEWA, S.—Investigation of Ova of Caprella ferox é Way ial iceate

Lucxensy—Preparing and Mounting Insects in Balsam ~s. i202 ae we
CamMpBELL, D. H.—Demonstration of Embryo-sac Dive
Hatstep, B. D.—Demonstration of Pollen-mother- celle ‘and ‘Pollew hes: So
Courter, J. M.—Continuity of Protoplasm in Plants sent inutee fe eae

(4). Staining and Injecting.
Nicken, E.—Staining reagents for Wood .. . Ghd Sales tien eae
Kuuye, H.—Staining of sections to show Micro-or: gantsms in situ

Scumi—Staining Tubercle Bacilli on Slides... oo) Say eee

(5) Mounting, including Slides, Preservative Fluids, &e.

Brown, A. P.—New Medium for Mounting Pollens and Starches... .« «.

Mauassez, L.—Rest for Slides and for Cullivation Plates: <5 \evess eee a
Perri, R. J.—WNitric Acid in Gelatin 1. ss au be te eee eee

(6) Miscellaneous.

Gassi, U.—New-and rapid method of oe the cane of Bacillus p pnewmonize

Hatcu, F. H.—Rosenbusch’s Petrographical Tables, an aid to the Atictecupéeate

Determination of Rock-forming Minerals

Carnexzy, T., & T. Winson—New Method of Determining the Number of Micro-

organisms in Air (Fig. 70)...

Orpmann—Value of Bacteriological Examination for Estimating ‘the ‘Purity af :

Drinking-Water~ .. Meme Ca
ARLoinc—Apparatus for the Bacteriological Examination of Water . 5

Tirmann, F., & A. GArrner—Chemical and Bacteriological Evamination 9
Water os ce ee
Kurn, L. — Diagrams of Microscopical Objects for ‘Class Teaching . os
Heoter, R.—Thallin, a new reagent for Lignin .. 6s se 4» 05 ow 0
Brarmer, L L.—New micro-chemical neaent for Tannin: oe ie esata
Mos.ier, H.— Tests for Tannin .. sarees

CostTaNnTIN, J. —New method of recognizing small ‘quantities of Invertin ot ees

PROCEEDINGS OF THE SocIETY ee «s AS Re we ee eo

ro

OCTOBER #1889.

—
TRANSACTIONS oF THE SoorETY—

IX.—Drscertion or A New Sprcirzs or Mrcatornoona. By
Surgeon V. Gunson Thorpe, R.N. (Plate XII)...

X.—Norz on Powarizina Apparatus For tHE Mronoscorr. By
Professor Silvanus P. Thompson, D.Sc. (Figs. 71-73)
SUMMARY OF CURRENT RESEARCHES,
ZOOLOGY.
A. VERTEBRATA :—Embryology, Histology, and General.
a, Embryology.

Wannace, A, R.—Darwinism ea Pk Mare ae Be Ie ROE tga Skis eal wae raey ae
Tuomson, J. A.—Heredity —.. Pale? aly aye rie igs Mig gs
Curtis, F. — Development of Natl in 2 Human Foetus .. Soper pee gh Mae ale
Mastus, J.—Formation of Placenta of Rabbit .. Gata

Bepparp, F. E.—Structure of Graafian Follicle in Didelphys.. eat bec ae ; :

Berarp, J.—Harly Development of Lepidosteus osseus .. «1 +e ue we wes
Niessinc, G.—Spermatogenesis in Mammals:, .. 1. se se te weet
Scuwarz, E.—Embryonic Cell-division .. .. 1. sn ee

Bf. Histology.

Lerypie, F.—Structure of Nerve-fibres .. Bret ee Pet

Fvsart, R.—Peripheral Nervous System of Amphioxus. SRC MAT tesa eG

Puatner, G.—Role of the Accessory Nuclear Body in Secretion... .. .. eee
vy. General.

Loncconin J. E. T.—Zoology of Afghan Delimitation Commission... ..

Mollusca.
Tentson-Woops, J. E.—Anatomy and paleo of Australian Mollusca .. ..
Carnibre, J.—Hyes of Mollusca «. Se bas aan ak y ae, Laas Seti es
y. Gastropoda.
Semon, R. —Secretion of Sulphuric Acid Py Marine Gastropods.. 1. +. ss
Leteiir, A.—Purple of Purpura lapillus a er

Henpaay, W. A, & J. A. Gina Sueddhewiehedecn of Liverpool District 1. «.
Beume, T —Anatomy and Development of Renal Apparat of eance Gastro-

pods... é apogee
MazzaRE.ui, G. F. —~ Reproductive Organs of ‘Aplysize SEE Ser ees EPO PIE
Molluscoida.
a. Tunicata.
‘Srevicer, O.—Alternation of Generations in Salpe 1. ss se an ue ae we
8. Bryozoa.
Waters, A. W.—Polyzoa of the Voyage of H.M.S.‘ Challenger’ 256. os
Bryozoa: of New South Wales: : 40 Se ee 0k et naw ea AS
Provno, H. ” Reproduction of Ctenostomatous Bryozoa .. swe es
Arthropoda,
Grassi, B.— Ancestors Hoss Myriopods- and: Inséche: oi o06 2 os iwi pe ee ox
a, Insecta.
Burien, A. G.—Insects supposed to be distasteful 16, Brg ek Sia: ah eke

Scuirrer, C.—Histology of Insects
Biocumann, F.—Number of Polar Globules in Fertilized and Unfertilized Hage of

PEER na Sa os
Luorant, L., & A. Prurri—Respiration of the Ova of Bony Pore ee aes
Grassi, B.— Termites a Penis Sets At

Ovupemans, J. T.—Abdominal Apvendages of a Lepismid .. 5 ae
Grarp, A.—Galls produced on Typhlocyba rose by a Hymenopterous Larva ..

b

PAGE

613

617

(49.
B. Myrionoda.
Hearucorn, F. G.— Anatomy of Polyxenua Tagurus is wc ees a ok

6. Arachnida.

APSsTEIN, ‘C. sp usture and Function of Spinning Glands BO Avance oe 2

BertKau, P.— Parasites of Spiders Pie ea Nie he ebie nee
Ge B., & & Rovevut—New Acarid 6. ay ee eye

e. Crustacea.

CatTaneo, G. SS Tnleatane’ of Decapoda and its Gland... ee
Rows, L.—Early Development of Blastodermie ayer im Teopota ep ben topes
Noruan— British Amphipoda «\.. He Li inie heh, eg arate ea ais

Misr, G. W.—Spermatogenesis i in Ostracoda .. 4.0 ce ay te
Girsprxcnt, W.—New Pelagic Copepods Ponies tale Fees
Leipy, J.—Neéw Parasitic Copepod fe Sed apne aia
Fow.er, G. H. -Hemarkable Cigatnccan Parasite Sea eae

Vermes.

qa, Annelida. :
Pruvor, G.—Formation of Stolons:in Syllidiang 2. 4.00 ek ae ewe

Vaiuant, L.—Natural History of Annelids sy og ne nee ae “aes

SHIPLEY, A. H.—Phymosoma varians vs ve ee og ee ne ne we

¥: Platyhelminthes, Atay
PLESSIS, G. Du—Oloplana intermedia ais 5 Way pear ce ae ae plea bee ORCI MR et

6. Incerteo Sedis,

Rovre, L eNews Becton of Phoronia sss 48) se ve ae ae
F RWKEs, J. W.-—-New Marine AT ft ROP IRN NONS GAM RI pA se Fae ow
Pehindaermeia. ) os
Lrpwie’s (H.) Batironlormat Are eae aron ate eete
Korscuer, E.—lormation of Mesoderm in ‘Echinoderms PRESSE AEE UAC vag
SuapEN, Percy W —Asteroidea of the Voyage of the ‘ Challenger’ ae ne as
Coelenterata. ee

Happow, A. O_Reatsion of British Actiniz ees Petree may Uaioe 3S
McMorercn, J. P.—Actinology of the Bera PEN Terr Oy Oe, Sah ee
FEWKES, J: W.= Angelopsis Bai oteo- TEES, Vinny eta ath Nia gL tia poles Sign DRS etre mS

Porifera.
wece ues R.. v.—Structure of Flagellated Chambers in ‘Spontes, BERENS

Po.ssaurr, N.—Korotnewia desiderata and the Phylogeny of Eo Sponges. -

Hanitson,:R.—New British Sponge ss as oe ws

Protozoa.
Dancearp, P, A.—Ohlorophyll in lee (ES ia Bee tone pone cee eae “7
Bitscuu’s (O.) Protozoa... .. ApEn Meningeal Ian ay
CaBriben, J.—Parasitie Trichodina ay geen eit :

Deicuter, C.—Parasitic Protozoa im Hooping Cough ..
Crrtes, A.—Micro-Organisms in Paunch of Ruminants,
Cru & Gr pote Aol Ee Structure of the Plasmodium Malariee

BOTANY.

A. GENERAL, including the Anatomy and Physiology

of the Phanerogamia,

a, Anatomy.
<5 (1) Cell-structure and Protoplasm.
Zacuartas, E.—Formation and Growth of the Cell-wall

(2) Other Cell-contents (including Secretions).
HANSEN, A.—Pure Chlorophyll 6. se ue a .
Kraus, G.—Physiology of Tannin... -
Kout, "B. G.—Formation of Calcium oxalate in Plants
Montrverpe, N. A.—Injluence of Light on the formation of Caleium oxalate
Atmuquist, S.—Production of Honey in Convallaria .. 1.) se vas

o6 eo. oo

ee oo! ee

oe

ee

658

- 653 ©

654
650
655

655

Cibo)

(3) Structure of Tissues.

Pronet, A.—Foliar Vascular Bundles 1.00.0 005 ee ee te ne ee 655
LaBarte—Anatomy of Floral Aves... - PTs 656
ANDERSSON, S.—Development of the Vascular bundles of Monoootyladons 656
Lautersacn, O.—Seeretion-receptacles in the Cactace ay 656
eae G: A. —Pransfusion-tissue of Conifere _.. oe 657
R6sELER, P.—Increase in thickness of the arborescent Liliacox x 657
Tevin—Primary Cortex in Dicotyledons 1. *" ne ee ee se 658
Wrvre, A. pe—Pericycle — % 659
SavvaGeau, L.—Mechanical System in the Ruots of Aquatic Plants. 659
SoLereper, H.—Comparative Anatomy of the Aristolochiacex .. 680
Garoin—Strueture of Apocynacer .. 22 6. we ee 660
Junenar, J. R.—Anatomy of Dioscoreacer .. Steet EA og ih gat en eye OOO
SO DER, W. S.—Fibres and ise sated We Mantra aS ee a I eae
: (4) Structure of Organs.
ScHUMANN, K- — Obdiplostemonous Flowers .. 661
HALSTED, B. D.—Pollen-grains —.. oie 661
Tscuernicu, F.— Form of Pollen-grains s 661
AumQuist, S.—Nectarial Scales of Ranurculus 662
Daniet, L.—Structure of the Bracts and Bracteoles in the Tnvolucre ‘of orymbifera 662
: Boniztowsb1, J.—Development of Berry-like and eee Fruits A 662
Meyer, A.—Septated ithe of Umbellifere ..... os 662
JuMELLE, H—Fruit of Grasses .. bean Sage ee 663
Francuet, A.—Primula with Anatropous Neel a 663
Anrcaneenl, G.—Seed of Victoria os 1. es se ee awe 663
Scuumann, K.—Borragoid Inflorescence... .. ss 663
Counter, §.—Leaf of Taxodium 664
TincHem, P. Van, & H. Dovtior—Origin of Rootlets 664
Pianta, A.—Oomposition of the Tubercles of Stachys tuberifera 665
rier gli of the Haustoria in Parasitic hee punts: ein Qik ants gph OD.
Kocn, .L4—Haustoria of Rhinanthacez . Se Be Vea Alen BOO
ee ee Aeon # in the Roots of Grasses growing an “Water pelea Orion, vic P OOE
fB. Physiology.
(1) Reproduction and Germination.
Damuer, U.—Diclintsm and Hermaphroditism .. s,s. ee ne ee neve ~~ 667
Extot, W. G., & W. Trevease—Trimorphism of aoa a Bae 4s 667
Marter, G. E.—Pollination by: Lepidaptera.. 22 2.9 — ses Soe! soe 8 be ow ae yet 66T
PAmMeEr, L. H.—Perjoration of Flowers by Tnedcta <0 2k ee OE
(2) Nutrition and Growth (including Movements of Fluids).

JUMELLE, H.—Development of Annual Plants... 668

RosenvineE, Kotpervr—Injluence of External Agents on the Polarity and Dorsi-
pelea Structure of Plants’ .. e re Sata ares 668
are es :+One-sided Hardness of Wood - ee 669
Mer, E.— Influence of Exposure on the Growth of the Bark ‘of Coni ‘fers ae 669
JUMELLE, H.—Chlorophyllous Assimilation and Transpiration ... .. 669
» _ Influence of Mineral Substances on the Growth of Plants .. 669
ARCANGELI, G.—Trophilegice Function of Leaves... .. -.. a 670
Harrie, eee of Sap in the Wood ..-.. Samer page as 670
Devaux, H.—LEachange of Gases in Submerged 577 SCTE Ciro. Re seca
CHMIELEWSKIJ, W.— Absorption of Water by Leaves .. .s eT OEE
RopEWALD, H.— Changes of Substance and Force connected with Respiration... 671

y- General.

Paver. E.—Chlorosis... .. Peay Take? ale 671
Vuruuem’ s Vegetable Biology oF aes + 671
B. CRYPTOGAMIA.

Cryptogamia Vascularia.
Haswart, W. A.—Psilotum and few oles 2 - , 672
Stour, D _—Calamariez enceag as Ae a 673

C78)

Muscines,

Puiipert—Peristome .. arene eM RACED AU fe
GRONWALL, A. L.— Inflorescence of ‘Orthotrichum Rite Rien Yer rine ie rs a

GraveT, F.—Colouring-matter of Sphagnacez .. .. 40 ws ev ne tw

Alges. betes

Went, F. A. F. C.—Vacuoles in Algz.. oe. wen hw to oxen a eaneee
GuienaRrD, L.—Antherids and Pollinoids of Floridex whl saul fade eal ag tam

Hi » _ Antherozotds of Fucace# .. $a te U8 Le ats ee Bae eee
Borner, E.—Lctocarpus .. nn te Oh dina Shae RON! Nee eee ay ae
Soperstrom, E.—Desmarestia ‘aculeata .. aD sO ue CS pe oed Rup oh wah a aia aaa

Hanztor, P. —_Delamarea, a new genus of Phaosporce - RCN ieee Ntpy ea
HanseirnG, A.—Phexodermatium .. Bsifis eae ee se tala’ ON aie
Ksrtiman, F. R.—Frond of Chordariacce .. PON ery Cera
Boxtpt, R.— Distribution of Desnudiacez

Mautory, M. L., G. W. Rarrer, & J. BE. Lae— Ve Volvos globaton. : 4 coe

Fungi,

ELEY SEH W.— Conjugation of Nuclei in the DES: of Fungi PaCS

Bourque ot, H.—Saccharine matters of Fungi .. .. « «se «+ 08 «« +»

Noacs,: F.~—Mycorhize-forming Fungi cc5 fee aa Sa ea a ee ee ae

Hartoe, M.—Structure of Saprolegniacer .. 1. s» se us ee on ue oe
DisrE., P.—Germination of Teleutospores 1...) 54 “ue be ew 0 we
Hesse, R. Pia and Bld phomycetes® Se. Ss oct es aes tone oe eye ae

Bonnier, G:—Synthesis of Lichens.. .. Salto cans, Shee Bee aE
55 Development of ihe on the Drabaene e of ‘Moéses iy Wice Uinta

Fries, T. M—Pilophorus sie e Ja Sine eon Cormeen Sore

_ Sapepzck, R.—Fungus-parasites of Hie. Adilep ' 2 po ee ee
Emam, E., & E. Rostrurp—Rhizvetonia .. ere

Vuniemin, P., & EK. PriiiiEvx—FParasitic Fungus 0 on n the Eonbardy Poplar Eas,

BasBiani, E. G.—Entophytes tn Mapetepons 65 ok > ae eet ener a

Massan?, J.—Heliotropism of Phycomyces .: 4. 6s ae ne eww
DieteL, P.—Puccinia vexans ..
Mevzir, B.—Saprophytic development of parasitic “Fungi sk ease orat aca enn aia ae se
Eriksson, J.—Haplobasidion, a new genus of Dematien ., 2. se ee wee
Cuopat, R., & P. Cuvrt—Lactarius piperatus ie RLS ea ea AR eee ake

Mycetozoa.

Ravungiam, C.—Myxomycetes of Denmark... ss 1 su ue ete ee we
BacrporsKl, Mi—New: Myxomected so be len 'tvve eu a0 2% ah we ae te ee

Protophyta.

Qo Schizophycee.
Casrracane, F Oyelaphork a sil Phe bic Siete, ck ap ae Sees alow eeee
pF » Diatoms of African Tripoli er ee 7 ee

8. Schizomycetes.
Giaxa, DE—Number of Bacteria in the Contents of the Gastro-enterie Tube of some

“Animals per wield acme Le ee rhe 0)

Rwrscu & pv Bourcver—New Pyogenetic Bacillus . Bey loan oe Re teen Rae

DowprsweLi, G. F.—New Species of Chromogenous Microbe ods mts lap eaten, Coke

MICROSCOPY.

o. Instruments, Accessories, &c.

(1) Stands.

Binocvutar Microscopes (Ahrens, Goltzsch, and Holmes) (Figs. 74-77) .. +.
Bu1x’s (M.) Microscopes for ere the radia vs the curved sue of the eye
(Figs.'78-81) ....

- Ross's (Aaa Serew and Pinion Ooarse- and Fine-Adjustment ‘Figs. 82.

and 83) .. Aes COLT a AG
M‘Intosu’s (L. D.) Microscope Attachment (Figs, BL By Din sili ov, ea
Oup Italian Microscope (Wigs 88) 2 wie is wen api pk an ie ips ea ap eae

ee ee ae eo ee <0

684 —

685
688
691

. 692

695

jew eS,

(3) Illuminating and other Apparatus.
Tayior's (J.) Oleomargariscope (Figs. 89 and 90) ..
Hevurox, H. van—Recent Improvements in Electric Lighting applied ‘to Miero-
graphy and Photomicrography (Fig. 91) .. «. Ba ahya'p
(4) Photomicrography.
Supputu, W. X.—“ Artistic Photomicrography attained” gan Canes es
Zeitnow, E.—Photomicrography and the Chromo-copper Light -filter’ sai Cag eae
(5) Microscopical Optics and Manipulation.
Osperzeck, A.—Simple Apparatus for measur ing the Magnification of Optical
Instruments (Figs. 92-94) 2... Gad ie Rit whee ae Vege Te Sp
(6) ‘Miscellaneous.
CELEBRATION of the Third Centenary of the Invention of the Microscope oo ee
B. Technique.
(1) Collecting Objects, including Culture Processes.
Maupas, E.—Culture of Imfusoria 1. sees oe eee se et we
(2) Preparing Objects.
Boum, A. A.—Preparing Eggs of Petromyzon — ..
Srarr, IT. W.—Preparing and Mounting with Pressure Insects entire, as Trans-
parent Objects... «+ weet hale oa
FrirepuAnpger, B.—Preparing Central Nervous System of Lumbricus. Sate Yai
Hyatt, J. D.—Preparing Sections of Spines of Echinus .. 1. +s 08 as
Sumer, H.—Hzamining a Shell-bark Hickory Bud... 2. 40 ewe ws
Smitry, C. W.—White’s Botanical Preparations... .. .» « te ees
Gintuer, C.—Bacterivlogical Technique». su ue ue ete
(8) Cutting, including Imbedding and Microtomes,
MING, Gh Di): Meoratome: CHigs QD)y vai scse/ tee Sipe bet nenas wed aay ee Ne
Paouetti’s (V.) Improved Microtome
. DarkscHEWwITscH, L.—Method sae heving Serial Sections in order during manipu-
lation Bon eet nb Py Poca eet eC TRAE ERG Pie eR eee
(4) Staining and Injecting.
LoeFr.LeR, F.—New Method of Staining the Flagella and Cilia of Micro-organisme
Kossinsx1, A.—Staining. differences in resting and active Nuclei in Pele ont
Adenoma, and Sarcoma .
Martin, eo he method of Staining the Tubercle Bacillus in Tiguids a and in
tissues o
Scutrz, J., & F. 7 ‘Jamus—Staining aud Detection of Gontboand SEER
DINEUR, E. —Simple and rapid Method of staining Bacillus tuberculosis in
sputum... ve tee. ee
Norper.ing, K. A. —New Method jor staining the Tubercle Bacillus
Gace, Simon H., & Mrs. 8S. P.—Staining and mounting fe which have been
treated with Caustic Potash or Nitric Acid ies pais Serer hAs
Vines, 8. H. ee ene the Walls of Yeast-plant Cells ..
Fiemmine, W.—Solubility of Fat and Myelin in esl eee Oil after t the action of
Osnite Acta > Serie eo tek fe ae Siietve
(5) Mounting, including Slides, Preservative Fluids, &c.
Vorce, C. M.—Hints on Mounting Objects in Farrant’s Medium... 4, se
WALEER, C. H. H.— New Cell ee oe se se oe *- oe oe ee
Quinn, E. P.—Mounting in Fluosilicate of Soda Eps tage PP a a ee
Bwweiyy:W. D—The Bidwell-Cabinets es) 53 he ee a pe ues oe ae
(6) Miscellaneous.
FrarnkeL, C., & A. Pretrrer—Microscopical Atlas of Bacteriology .. «2 ss
Rock woop, G. G.—Detecting Alterations in Manuscripts .. 1. 4s sek ws
Fe ROOHEDINGS OF THM HOOINTE $3 40 5c ee aes Cae aha ae

PAGE

696
696

698
700

700

702

Numerical
Aperture.
(n sin u = 4.)

APERTURE TABLE. oe
Limit of Resolving Power, in Lines to an Inch.

Corresponding Angle (2 2) for

Air

(m = 1°00).

——————— | oO

Water

(m = 1°33).

oe

Homogeneous

Immersion

(m =1752).

180° 0!
166° 51!

“161° 23"

157° 12’
153° 39’
150° 32’
147° 42’
145°. 6".
142° 39’
140° 22’
138° 12'
136°. 8"
134° 10°
182° 16’
136° 26’
128° 40’
126° 58!
125° 18’
123° 40’
122°°.6!
120° 33’
117°. 35°
114° 44’
111°. 59’
109° 20’
106° 45’
104°. 15!
101° 50’

99° 29!

ashes

94° 55!
92°. 43°
90° 34’
88° 27'
86° 21’

~ 84° 18’
~~ 82° 17!

80°. 17’
78° 20°
- 76° 24°
74° 30’
72°. 36’
70° 44’
68° 54’
67°. 6!
65° 18’
63° 3L’
61° 45’

60° .0"-

58° 16’
56°. 32!
54° 50’:
53° 9!
51° 28"
49° 49)
48° 9
46° 30’
44° 5]/
43° 14!
41°. 37’
49° 0!

White Light.

Monochromatic
(Blue) Light.

(A = 0°5269 p,| (A = 0°4861 ys, | (A =0°4000 p,

Line E.)

146,543
145,579
144,615
143, 651
142,687
141,723
140,759
139,795
138, 830
137,866
136,902
135,938
134,974

134,010-

133,046

132,082

131,118
130,154

129,189
128,295.

127,261
125,333
123,405
121,477
119,548
117,620

115,692

113,764
111,835
109,907
107,979
- 106,051
104,123
102,195
- 100,266
98, 388
96,410
94,482
92,554
90, 625
88, 697
86,769
84,841
82,913
80,984
79, 056
77,128
75,200
73,272
71,343
69,415
67,487
65,559
63,631
61,702
59,774
57,846
55,918
53,990
52,061
50,133
48,205
43 (385
38, 564
33,744
28 923
24,103
19,282
14, 462
9,641

4,821

Line F.)

158,845
157,800
156,755
155,710

154,665

153,620
152,575
151,530
150,485
149,440

148,395
147,350.

146,305
145,260
144,215

143,170

142, 125
141, 080
140,035

138,989

137,944

135,854

133,764

131,674
129,584
127,494

125,404
123,314
121,294
119,134
117,044
114,954
112,864
110,774
108, 684

106,593.

104,508
102,413
100,323
98 , 233
96,143
94,053
91,963
89,873
87,783
85,693
83, 603
81,513
79,423
77,333
75,242

73,152.

71, 062
68,972
66,882
64,792
62,702

60,612

58,522
56,432
54, 342
52,252
47,026
41,801
36,576
31,351
26,126
20,901
15,676
10,450

5,225

Photography.’ see
near Line h.) f (=)
193,037 | 2-310 | -658
191,767 +280 *662
190,497 | 2- “667
189 , 227 *220. | +671
187,957 “190 | *676
186,687 | 2-161 | -680
185,417. los “68d
184,147. 7108 *690
182,877 ea 694
181,607 | 2-045 |. -699
180,337 2: “704
179,067 | 1: 709
177.797 : “714 |.
176,527 | 1-982 | -719
175,257 | 1-91 125
173,987 | 1-877 | +729
VIZ TAY ke ace 30°"
171,447 de “741
170,177 : -746
168, 907 a "752
167,637 = “| *758
165,097 | 1-¢ 769
162,557 | 1-638 | -781
160,017 : “794
157,477 | 1-538 | -806
154,937 | 1- +820
152,397 J 1” 833
149,857 | 1- 847°
| 1473317 | 1-346 | -se2”
144,777 | 1-300 | -877
149,937 | 1-954 | -893-
139.698 | 1-210 | -909
137,158 | 1-166 | -926
134,618 | 1-124 | -943-
132,078 | 1-082 | -962
129.538 | 1: -980
126,998 1-000
124,458 1°020 —
121.918 1-042
119.378 1-064.
116,838 “1°087
114,298 | 1111
“111,758 1 1-136
-*109,218 - 1-163.
106,678 1-190
1043128 1-220
101,598. 1-250
99,058 1°282
96,518 1:316
93,979 1°351
91/439 ~ 1-389
88/899. 1-499
~ 86,359. 1-471
83,819 1°515
81,279 1562
78,739° 1‘613
76,199 | 1-667
182609 bse 1°724 —

ait ee i! +314. | 1:786

68,579 : 19852

66,039 270 | 1:923-
63,499 J 2-000
57,149 | +203 | 2-222
50,799 | 2-500
44,449 “123 | 2-857
38,099 -090 | 3-333
31,749 : 4-000
25,400 | 5-000
19,050 -023 | 6-667
12,700 “010 {10-000

6,350 -003 {20-000

COMPARISON OF THE FAHRENHEIT AND CENTIGRADE THERMOMETERS.

Fahr. Centigr. Fahr. Centigr. Fahr, Centigr. Fahr. Centigr. Fahr. Centigr.
° ° ° ° °o ° fo} ° °
212 158 70 104 40 50 10 - 4 - 20
210°2 156°2 69 102°2 482 9 —- 5°8 |= 9]
210 156 68:89 102 88°89 48 8-89} - 6 = 21:1
208° 4 154°4 68 1004 83° 46°4 8 = 7°96 | =22
154 67°78 100 37°78 46 7784 -—- 8 — 22°92
206°6 152°6 67 98°6 44°6 7 - 94 | -9383
206 152 66°67 98 36°67 44 6:67} — 10 — 23°33
204:8 150°8 66 96°8 42°8 6 - 112 | -24
204 150 65°56 96 35°56 42, 5°56 | — 12 — 24°44
203 149 65 95 41 5 -138 = 25
202 148 64°44 94 34°44 40 444] -14 = 25°56
201°2 147°2 64 93°2 39°2 4 - 14°8 |-—-26
200 146 63°33 92 33°33 38 3:33 | - 16 — 26°67
199°4 145°4 63 91-4 87°4 3 =- 16°6 | -27
198 144 6222 90 32°22 36 2:22] - 18 — 97°78
197°6 143°6 62 89°6 35°6 2 ~ 184} =
196 142 61°11 88 31°11 84 1:11 f - 20 — 28°89
195°8 141°8 61 87:8 31 338 1 — 20:2 | -29
194 140 60 86 30 32 O - 22, - 80
192°2 138+2 59 84-2 30°2 eee | - 23°8 | =81
192 1388 58°89 84 28°89 80 - l:ll}j - 24 = 381'll
190*4 136°4 58 82°4 28-4 eg - 2:6 | -8
190 186 57°78 82 27°78 28 — 2:22} -26 — 32-22
188°6 134°6 57 80°6 26°6 = 8 —- 27°4 | = 8
134 56°67 80 26°67 26 - 3°33} -28 — 83°33
186°8 132°8 56 78°8 286 24-8 - 4 -— 29°2 | -34
186 132 55:56 78 25°56 24 - 4:44} - 30 — 34+44
185 131 55 77 23 - - 31 - 85
184 130 54:44 76 24°44 22 —- 5°56) — 32 — 35°56
183°2 129-2 54. 75°2 21°2 - 6 — 32°8 | -386
182 128 53°33 74 23°33 20 - 6°67 4 — 84 — 36°67
181°4 127-4 53 13°4 19°4 - 7 - 346 }-3
180 126 i 52°99 79 22°22 18 = 7°78) —36 = 37°78
179°6 125°6 52 71°6 22 17°6 - 8 - 36:4 | - 88
178 124 51-11 0 21-11 16 = 8°89 J — = 38°89
177°8 123°8 51 69°8 21 15°8 - 9 - 88°2 | - 39
176 122 50 68:2 20 14 - 10 - 40 - 40
174:2 120°2 49 66 19 12-2 - 11 - 41°80} - 41
174 120 48°89 66:4 18:89 12 - ll-ll |] - 42 ~ 41-11
172°4 118°4 48 64 18 10°4 -] - 43°60} -4
172 118 47°78 64:6 17°78 10 — 12°92] -44 = 42°22
170°6 116°6 47 62 17 86 -1 - 45°40| -438
170 116 46°67 62'8 16°67 8 — 13°33] -— 4 — 43°33
168°8 114°8 6 60 16 6:8 = - 47:20| - 44
168 114 45°56 60 15°56 6 —- 14:44] -48 — 44°44
167 113 45 59 15 5 -15 - 49 - 45
166 112 44°44 58 14°44 4 = 15°56] - 50 — 45°56
165*2 111°2 44 57°2 3°2 -16 — 50:80} -4
164 110 48°33 56 13-33 DA — 16°67 | - 52 — 46°67
163°4 1094 43 554 14 -17 — 52°60) - 47
162 108 -| 42-22 54 12°22 0) = 17°78 | ~54 = 47°78
161°6 107°6 42, 53°6 = 074 -18 — 54:40| -4
160 106 Al-I1 52 ll‘1l | -2 - 18°89 | - 56 — 48°89
159°8 105°8 4l 518 ll - 2°2 ~ 19 - LR ~ =
~ 58 -

FAHRENHEIT

_ A030 2 “i 0 10 20 30 40 “a a 70 80 SO eA RRA TTR 212

40 30 20 10 0 10 2 30 49 50

’ CENTIGRADE

( 10 )
GREATLY REDUCED PRICES

OBJECT- -GLASSES MANUFACTURED BY

R. & J. BECK,

68, CORNHILL, LONDON, E.C.

PRICES OF BEST ACHROMATIC OBJECT-GLASSES.

Angle Linear magnifying-power, with ro-inch
No. Focal length. aber. Price. wae hue Sade) ermine
ture 2
: about | No. 1.| No. 2.] No. 3.|No. 4.| No. 5.
£8. d.
100 3 mehes ee 9 : me S be) 16 30 40 50
101 inches Se ate 7
102 | Binches .. ..| 12 | 210 0 } oleueg ec
108 | 2inches .. .. | IO
104 | Qinches’) 5. ..-| 17°| 210 0 } 22, 36 | 67) 90) I1
a5 1 pe Ee Sten eAe ged ae . x6 ° 30 48 9° | 120 150
3 wo ee ee 2 i
107 Bainch Mee ak ce 210 0 \ TOE REAR eg oa
108 | finch ..) .. «2 } 45 210 0} 100] 160] 300| 400} © g00
109 | s;inch.. .. «2 | 65 4 0 0} 125 | 200} 375 | 500 625
110 | -4 inch... 2, 95 5 O O| 150] 240} 450 | 600 750
111 i INeh E325 iret bat 75 3.10.0} 200] 320]| 600] 800 | 1000
112 | 2 inch ssa $20 410 0| 250} 400} 750 | tooo} 1250
ALS} 2 meh. ake [2130 5 O O}| 400} 640 | 1200 | 1600 | 2000
114 | 3, imn. Pra ee ale) 5 5 0} 500] 800} 1590 | 2000 | 2500
115 | = imm. Sa path of0) 8 O O|- 750 | 1200 | 2250 | 3000 | 3750°
116 | 3 imm. vs es | 180 | 10 O O } 1000 | 1600.) 3000 | 4000 | 5000°
117 | dinch.. ..... | 160 | 20 O O | 2000 | 3200 | 6000 | 8000 | 10,0G0_—
7 eae Bs i :

ECONOMIC ACHROMATIC OBJECT-GLASSES,

APPLICABLE TO ALL INSTRUMENTS MADE WITH THE UNIVERSAL Screw.

Angle MAGNIFYING-POWER,
of with 6-inch body and
No. Focal length. aper- Price. eye-pieces.
ture, Pesemeabi sens SAS ASS so
about No. 1.| No. 2.) No. 3.
iS £ s.-d.
150 | 3 inches : 6 100 12 15 27
151 | 2 inches ayer 8 10 0 18 23 4I
152 | 1 inch 2 18 15 0 46 61. | 106
1538 | 4 inch SoA el bias 1) 4 Wa 9 ik ©) gO | 116 | 205
154 | 2 inch ‘ 8o | 1 5 O | 170 | 220 °| 415
155 | inch , ITO 2 5 O | 250 | 330 | 630
156 | iinch .. °. IIo 810 O | 350 | 450 | 800
157 | 3; imm. 180 6 0 O | 654 | 844 |1500

Revised Catalogue sent on application to
R. & J. BECK, GS, Cornhill.

OURN.R MICR.SOC.1889. Pl Xi.

—)

West, Newman lath.

emibullata.

otrocha §

Mega

JOURNAL

OF THE

ROYAL MICROSCOPICAL SOCIETY.

OCTOBER 1889.

TRANSACTIONS OF THE SOCIETY.

IX.—Description of a New Species of Megalotrocha.
By Surgeon V. Gunson Tuorpsz, R.N.

(Read 12th June, 1889.)
Puate XII.

Dorine the years 1886-9, whilst serving on board H.M.S. ‘ Paluma,’
employed in the survey of the waters between the east coast of
Queensland and the Great Austvalian Barrier Reef, many opportunities
were afforded me for the study of microscopic life, both fresh-water
and marine. Whilst the higher forms of both the fauna and flora of
Queensland are being very thoroughly worked out, this branch of
natural history has been almost if not quite untouched. This fact
stimulated me to devote my leisure moments to the study of the
microscopic life of the colony, and especially to that of the Rotifera.
The localities in which Notifera are to be found in Queensland are
few and far between ; water, except at certain times of the year, being
scarce in that tropical climate. In May, soon after the rainy season,
one occasionally comes across, in the midst of the dense Australian
bush, a charmingly secluded little pond, shaded on all sides by
Eucalypti, grass-trees, and acacias, with lilies, ferns, and orchids
growing in great profusion around; brightly coloured dragon-flies
and other insects flitting across its surface ; parrakeets and cockatoos
screaming overhead. The water of such a pool teems with various
species of Floscularia, with Melicerta conifera and ringens, Limnias
annulatus, Brachionus militaris, and many other kinds. Three
months afterwards, the same place may be found completely dried up,
and the ground fissured in all directions by the fierce heat of the sun;
and yet, in the following year, the same locality is as prolific as ever.
Again, in marked contrast, at another time one meets with a tiny
pool, not more than three or four feet across, on the bleak and rocky
headland of an island out at sea, exposed to the storm and to the

EXPLANATION OF PLATE XII.

a, dorsal surface; b, ventral surface; c, side view; d, corona contracted ; é, view
of head from above ; f, mastax; g, male.

1889. 2U

614 Transactions of the Society.

glare of a tropical sun, breakers beating on the rocks below within
twenty feet of it, with no life to be seen but the eagle soaring over-
head, and no sound to be heard but the mournful cry of the dingo as
the sun goes down; and yet, strange to relate, I found the water of
such a solitary and apparently lifeless pool* literally swarming with
the wonderful Pedalion.

It was whilst examining the water of a pond in the picturesque
gardens of the Acclimatization Society, Brisbane, in February 1887,
that I noticed the presence of a number of tiny white globes swimming
freely in the water, which I at first took for Conochilus volvox.
Further examination convinced me that I had found a new species of
Megalotrocha, an opinion afterwards confirmed by Dr. Hudson, to
whom I am indebted for much kind help and encouragement. He
proposed the name of Megalotrocha semibullata, since it carries but
half the number of opaque warts which adorn the body of M. albo-
flavicans, hitherto the only known species of this genus.

The following are the specific characters of this new Rotiferon :—

Se. Cu.—Cluster spherical, free-swimming, consisting of many
adults and their young. No coherent gelatinous tubes. Corona
somewhat quadrilateral, the axes being nearly equal; oblique, and
looking towards the dorsal aspect. Ventral sinus shallow. Trunk
with two opaque warts, one on each shoulder, on the ventral surface
below the corona, and between it and the ventral antenne. Ventral
antennz below the corona and the opaque warts, as two small
setigerous pimples, standing on the arched ventral surface. Dorsal
antenne absent. Hyes two, bright red, on the upper edge of the
dorsal surface of the ciliary wreath, between the inner and outer
rows of cilia.

From the above brief description it will be seen that the resemblances
to the only known species of this genus, viz. M. alboflavicans, are
(1) the possession of opaque warts on the ventral surface below the
corona; (2) the dorsal position of the gap in the ciliary wreath (gen.
ch.); and (8) the absence of gelatinous tubes. The differences are—
(1) the possession of eyes in the adult individual; (2) the possession
of antenne; and (8) in the fact that it is free-swimming. These
differences will therefore cause some alterations in the generic
characters.

The cluster, consisting sometimes of as many as seventy individual
is perfectly visible to the naked eye, and is about 1/20 in. in diameter; t
each individual being about 1/40 in. when fully grown. Although
I examined the leaves of the water-plants very carefully, in no instance
was I able to recognize any attachment to the leaf.

The general anatomy of the individual rotiferon resembles in the
main points that of M- alboflavicans, but a few points require special
notice.

* This promontory will be known in future Admiralty charts as Pedalion Point,
Dunk Island.
+ A mounted specimen under pressure measured 1/12 in. in diameter.

A New Species of Megalotrocha. By V. Gunson Thorpe. 615

The junction of the pseudopodium, or foot, with the trunk is well
marked by a constriction, and presents a peculiar, and I believe
unique, structure. The dorsal surface of the upper extremity of the
foot is prolonged upwards and outwards, to form a triple expansion,
somewhat in the form of a trefoil. The middle portion of this process
projects prominently outwards on the dorsal aspect, and to it the eggs
are attached, after exclusion from the cloaca. ‘The lateral portions,
like buttresses, closely embrace the lower extremity of the trunk,
which is wedged in between them.

The ciliary wreath is almost quadrilateral, and is placed obliquely
looking towards the dorsal aspect. The animal has a habit of
doubling the corona on itself, so that a view from above can frequently
be obtained of the buccal orifice and the relative position of the two
warts to it.

The two opaque warts are situated one on each shoulder, on the
ventral surface below the corona. Hyen with a pocket-lens they may
be distinctly detected as little black dots scattered over the surface of
the white cluster-ball. When the animal contracts, they stand up
prominently above the surface of the indrawn head.

Below the warts, on the ventral surface of the trunk, may be seen,
by careful focusing, two minute setigerous pimples—the ventral
antenne—in position resembling those of Conochilus dossuarzus, but,
unlike them, being distinctly separate, a considerable space inter-
vening.

The ¢rophi are orange-tinted, and of the malleo-ramate type.
The unci, passing from the mallei to the rami, are three-toothed.
The extremity of each tooth attached to the manubrium is bifid, one
division being soldered to the upper surface of the manubrium, the
other division, curving backwards, lies in contact with its inner side.
The fulcrum is very slender, and appears to be double-jointed.

The esophagus is lined with quadrilateral cells, and has salivary
glands on either side. The stomach is capacious, richly lined with
cilia, with large gastric glands in contact with it. The ¢ntestine takes
a short sharp curve upwards towards the dorsal surface, and ends in
the cloacal opening at the junction of the upper three-fifths with the
lower two-fifths of the trunk.

The lateral canals possess two pairs of vebratile tags, one pair
within the corona, and one on either side of the stomach. A con-
tractile vesicle has not been detected.

The eyes are two minute bright-red spots on the upper edge of
the dorsal surface of the corona, between the inner and outer rows of
cilia, but nearer the inner wreath.

There is a large ovary between the ventral body-wall and the
stomach. The egg, after extrusion from the cloaca, becomes attached
to the middle portion of the triple expansion of the foot above
described. Two ova may often be seen thus attached, side by side, in
one or both of which the movements of the unborn rotiferon, with its
red eyes, may be distinctly visible. In one instance I saw a young

616 Transactions of the Society.

female, newly hatched, still fixed by its hinder extremity to this
oviferous expansion, side by side with an unhatched egg. ‘These eggs
not infrequently have sessile Vorticellz parasitic upon them.

In December 1888, I was fortunate enough to see the male in
actual coitus with a female, which had become detached from the
general cluster. The two gyrated round each other in circles at a
great rate, the male making several ineffectual darts, but finally
succeeded in attaching himself in the neighbourhood of the cloaca of
the female, who, by the speed with which she swam through the
water, appeared to be doing her utmost to shake her paramour off.
The male is about 1/200 in. in length, with the characteristic quadri-
lateral wreath, and two bright red eyes; the hinder extremity is
furnished with a short pointed foot. The sperm-sac fills nearly the
whole of the trunk.

The cluster is frequently infested with a species of micrococcus,
which especially attacks the oviferous expansion and its neighbour-
hood.

( 617 )

X.—Note on Polarizing Apparatus for the Microscope.

By Professor Smrvanus P. Tompson, D.Sc.
(Read 12th June, 1889.)

A Frew months ago the writer had adapted to his Microscope (a Beck’s
“ Pathological”) one of Ahrens’s triple polarizing prisms * which he
had for some eighteen months been using for other purposes. This
prism has an angular aperture of some 28°, far exceeding any ordinary
Nicol’s prism. ‘The prism is so short, in comparison with its area of
cross-section, that it appeared particularly convenient for the purpose
of a substage polarizer, provided the line of junction across the end-
face of the prism did not interfere with the optical performance.
The prism when removed from its mountings is a rectangular
parallelopiped, having square end-faces. The side of the square end-
face is 17°5 millimetres, and the length of the prism is but 27 milli-
metres. Mounted below a wide-angled Abbe-Beck condenser, as in
fig. 71, with an iris diaphragm between, it gives most satisfactory
results. The line of junction across the

upper end-face is barely to be detected, and Fig. 71.

gives no trouble in use. ;

As analyser several prisms have been
tried, the most satisfactory being a small
prism lately cut for me by Mr. Ahrens, for
the express purpose of use over an eye-plece.
The following considerations determined its
construction. It is obvious that it is of no
use to make the eye-end of the analysing
prism of greater diametral aperture than
that of the pupil of the eye. Any larger
aperture than this is not merely wasted, for
the prism that has a larger end-face than
necessary means a prisin that is longer than
necessary, and obliges the observer’s eye to
be further removed from the eye-piece. In
Nicol prisms, as ordinarily made, the two
end-faces are of equal size, and the lateral
faces are parallel. For analysing purposes,
however, the prism must have at the end
farthest from the eye an aperture greater than that of the pupil,
otherwise the eye cannot receive the proper cone of rays. Further,
the oblique end-faces habitual in the Nicol prisms of ordinary con-
struction are objectionable, as they waste light by reflection, and take
up valuable space. The prism which Mr. Ahrens has cut for me is
represented in fig. 72. It is about 11 millimetres long, narrower at
the end nearest the eye, and has end-faces square to its axis. These

* Phil. Mag., 1886, p. 476.
1889. a.%

618 Transactions of the Society.

end-faces are principal planes of section of the crystal, the optic axis
lying in them diagonally. The method of cutting the spar is a simple
modification of that adopted of late years by Mr. Ahrens, which, while
gaining the maximum angular aperture, causes least waste of spar.
Fig. 73 shows another way of attaining the same end by use of a simple
divided rectangular parallelopiped of spar, the upper and lower faces

of which are, as in the other form, principal planes of section. The
cone of useful rays is confined within the dotted lines. The analysers
can be used over either an A or B eye-piece.

For showing the rings and brushes in crystal sections with an
ordinary Microscope, I have adopted the following arrangement, which
is quite as satisfactory as the much more expensive arrangements
which go by the name of Norremberg’s apparatus for convergent light. .
The polarizer described above, together with the wide-angled Abbe-
Beck condenser, is fitted in its place in the substage. Ordinary
objectives are of little use for the purpose of showing the rings and
brushes. What is wanted is a very wide-angled objective of not very
high power. Not even the wide-angled apochromatic objectives now
in fashion are satisfactory. Instead of any of these, | employ a wide-
angled achromatic substage condenser (by Beck), which, being pro-
vided with the universal screw, can be removed from the adapter
which fits the substage and screwed into the lower end of the tube
instead of an objective. The eye-piece must be removed from the
draw-tube. ‘'T’o observe the rings and cross of a uniaxal crystal, or
the rings and brushes of a biaxal, the crystal slice is placed on the
stage, the substage condenser is screwed close up to it from below,
and the achromatic condenser in the tube is screwed down close upon
it from above. ‘The observer's eye is placed over the open upper end
of the tube. Thus viewed, the rings and cross or rings and brushes
appear quite small in the contracted field of light. ‘To magnify them,
the following very simple device is sufficient. A positive lens of any
focal length between 13 and 4 inches, according to the choice of the
observer, is placed about half-way down the tube. A spectacle glass
of 83-inch focus, snipped down with a pair of pliers and dropped into
the draw-tube so as to rest on the diaphragm, answers very well.
The arrangement shows the rings even of those biaxal crystals which
have very wide separation between the optic axes, such as gypsum
and topaz.

SUMMARY

OF CURRENT RESEARCHES RELATING TO

LO0 LOGY. AND BOTAN Y
(principally Invertebrata and Cryptogamia),

MICROSCOPY, &c.,
INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.*

ZOOLOGY.

A. VERTEBRATA :—Embryology, Histology, and General.
a. Embryology-.+

Darwinism.{—Under this title Mr. A. R. Wallace has published an
important and most interesting work in which he gives an exposition of
the theory of Natural Selection, with some of its applications. Mr.
Wallace, who remains true to his belief in the overwhelming importance
of Natural Selection in the production of new species, criticizes very
forcibly many recent speculations and theories. While using for his
purpose a number of facts already cited, he brings forward a quantity
of new evidence, especially on the subject of variations within the limits
of a species. He reduces the importance of sexual selection as a factor
in producing new species, and he claims for his book the position of
being the advocate of pure Darwinism. It is only necessary for us to
chronicle the appearance of this important work.

Heredity.§—Mr. J. A. Thomson furnishes a historical summary of
theories of heredity, discussing (a) those which sought to explain tho
uniqueness of the germ-cells by special hypotheses such as those
involved in “ pangenesis” ; (b) the gradual elaboration of the doctrine of
germinal continuity, from Owen and Haeckel to Jaeger and Weismann;
(c) the auxiliary theories of “ organic memory,” “ perigenesis,” chemical
continuity, &c., which seek to make the fact of reconstruction more
intelligible.

As to the inheritance of acquired characters, the author summarizes
the various opinions, emphasizing Weismann’s scepticism. The various
criticisms of Weismann’s conclusions based on concrete cases, on patho-
logical evidence, and on the general theory of evolution are briefly
summed up, while the author urges that the general symbiosis of the
organism, the common medium of the blood, the frequency of inter-

* The Society are not intended to be denoted by the editorial “we,” and they do
not hold themselves responsible for the views of the authors of the papers noted,
nor for any claim to novelty or otherwise made by them. The object of this part of
the Journal is to present a summary of the papers as actually published, and to
describe and illustrate Instruments, Apparatus, &c., which are either new or have
not been previously described in this country.

+ This section includes not only papers relating to Embryology properly so called,
but also those dealing with Evolution, Development, and Reproduction, and allied
subjects. { ‘ Darwinism,’ 8vo, London, 1889, viii. and 494 pp. (37 figs.),

§ Proc. R. Soc. Edin., 1888-9, pp. 98-116.

ri ap’.

620 SUMMARY OF CURRENT RESEARCHES RELATING TO

cellular connections, the rarity of early insulation of sex-cells, all favour
the possibility of environmental and functional variations affecting the
reproductive organs, and thus becoming transmissible.

Development of Nail in Human Fetus.* —M. F. Curtis has in-
vestigated the development of the nail in the human feetus. It follows
the law that the lower extremities are always developed more slowly
than the upper, and the dates which are here given apply to the nail of
the thumb. The formation of the bed of the nail commences in the first
week of the third month with the appearance of the first rudiment of
the posterior involution; the delimitation of the bed by a peripheral
groove is completed towards the middle of the third month. This last
is effected by a simple proliferation of epithelium; at this period there
is no fibrous band of perichondrial origin which can be considered as in
any way the cause of the folding of the epidermis. The area thus de-
limited in the third month may be called the primitive bed, for it is
composed of two segments which are separated by a secondary groove in
the first week of the fifth month. The anterior segment alone undergoes
the dorsal displacement described by Zander, and becomes later on the
region of the angle of the nail, homologous with the sole of the horse.
The dorsal segment which alone forms the nail may, from the fifth
month, be called the definite bed. The superficial layer which has been
called the eponychium really exists; it is a true stratum corneum
which, from the beginning of the fourth month, commences to appear at.
the anterior extremity of the bed. It then grows from before backwards,
and at the end of the fourth month covers the whole surface of the bed.
The eponychium becomes pushed off from the middle of the bed by the
growth of subjacent parts towards the end of the fourth month, and its
two extremities alone persist; the posterior of these forms, at this period,
the perionyx, while the anterior becomes a persistent thick horny layer
at the angle of the nail. In the second week of the fourth month a
group of cells is differentiated at the centre of the bed, and in the midst
of the mucous body which will give rise to the primitive matrix. This
is composed of cells with grains of keratin, but these elements disappear
during the ninth month. By the deposit of fresh layers the primitive
nail is formed after the rupture of the eponychium ; this is characterized
by its origin from the keratin-containing cells which disappear later on,
by its loose irregular structure, and its constant superficial exfoliation.
It is really impossible to say quite exactly when a distinct layer deserving
the name of a nail first appears; it is by slow and continuous sub-
stitution that the primitive nail displaces and replaces the eponychium.
The primitive nail having covered the bed extends from before back-
wards. While the hinder part of the matrix is displaced, the central
part becomes the seat of a new development, for the epithelial cells
change in form and become filled with fine granulations of onychogenous
substance. The epithelial development of the matrix carries with it the
production of new unequal layers, which are distinctly striated, and
exhibit no tendency to superficial exfoliation. They constitute the
definite nail, and it is, again, by a process of slow and continuous sub-
stitution that the definite nail displaces and replaces the primitive nail.

The production of an eponychium, of a primitive and of a definite

nail are three connected facts which succeed one another in a regular and
constant order.

* Journ. de l’Anat. et de la Physiol., xxv. ( 889) pp. 125-86 (2 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 621

Formation of Placenta of Rabbit.*—We have again an account of
the development of the placenta of the Rabbit, M. J. Masius now being
the author. Previously to the formation of the blastocyst the mucous
membrane of the uterus becomes very thick, and forms on its surface
large papille ; these, which are separated from one another by narrow
crypts, form a large projection on which the epiblast is fixed and the
placenta developed. Neither the glands nor the epithelium of the uterus
take any part in the formation of the placenta. The vessels of the
mucous membrane become surrounded by a sheath of cells which are all
derived from the fixed cells of the dermis; these sheaths are developed
by the mitosic division of the cells which constitute them, acquire a
large size, and form the dominant mass of the dermis in the advanced
stages of the formation of the placenta. The endothelium of the vessels
of the mucous membrane degenerates and disappears; when it disappears
the perivascular sheath directly bounds the cavity of the vessel and the
blood may filter in small quantities through the perivascular cells.

In the early stages the mucous membrane contains a large number
of elements which the author regards as leucocytes; these become con-
verted into corpuscles formed of a moniliform chromatic cord or of
chromatic granulations. These cells are scattered in the dermis of the
mucous membrane and in certain vessels, but the author does not yet
know what their function is.

Just before the fixation of the blastocyst to the mucous membrane
two layers may be distinguished in the embryonic epiblast; the deeper
one has cylindrical cells, the outer has nuclei arranged in nuclear
nests and there is no division into cellular areas. It is by means of this
superficial layer that union is made with the uterine mucous membrane ;
the layer soon becomes enormously developed and forms a multi-
nucleated protoplasmic mass into which the deeper epiblastic layer
sends primordial papille, at first non-vascular and formed of epiblast
and somatopleure. On the other hand, the capillaries of the mother
become engaged in this multinucleated protoplasm of fcetal origin,
where they lose their endothelium, and become continuous with a
system of numerous lacune without proper walls.

The allantois, by fusing with the serosa of Von Baer, vascularizes
the primordial papillae by forming in them a connective axis rich in
blood-vessels. But, as this fusion is effected, the deep layer of the
epiblast becomes interrupted around this connective axis of allantoidean
villosities. As a result of this, the maternal blood of the placenta
circulating in large lacunar spaces is, in many places, separated from the
connective vascular villosity by nothing more than a more or less thick
layer of multinucleated epiblastic protoplasm.

The author regards the placenta of the Rabbit as a new formation of
foetal origin formed by allantoic villosities branching in a tissue which
arises solely from the epiblast of the embryo. This new formation
becomes fused with the dermis of the mucous membrane, the vessels
of which form quite a system of lacune without proper walls, which
traverse a multinucleated protoplasmic mass not broken up into cell-areas,
and owing its origin to a very great increase in thickness of the superticial
layer of the epiblast. In the placenta the maternal blood circulates in
an epiblastic mass of embryonic origin.

* Arch. de Biologie, ix. (1889) pp. 83-121 (4 pls.).

622 SUMMARY OF CURRENT RESEARCHES RELATING TO

In the course of the development of the placenta the cavities of the
crypts lined by much altered uterine epithelium may be filled with
maternal blood; this is due to the presence in the crypts of holes with
no proper walls, which traverse the epiblastic mass in such a way as to
establish communications between the lacunar blood-system of the
placenta and the epithelial crypts. This arrangement allows of the
presence of the maternal blood between the epiblast and the surface of
the mucous membrane of the uterus.

Structure of Graafian Follicle in Didelphys.*—Mr. F. E. Beddard
gives an account of the Graatian follicle in the Opossum, which agrees
more closely with that of Phascolarctos than with that of Phalangista ;
that of the last-named Marsupial seems to the author to nearly represent
the hypothetical intermediate condition between the Monotremata and
the higher Mammalia.

Early Development of Lepidosteus osseus.t—Dr. J. Beard gives an
outline of the development of Lepidosteus during the first three weeks
of its life. The investigation of that of the first four days is very
difficult ; for the yolk outside the embryo gives rises to technical
difficulties, while that which fills all the cells renders everything
blurred and indistinct. As to the egg the author has little to add to
the description given by Balfour and Parker. The blastopore closes on
the second day, and at no time is there a neurenteric canal ; the mesoderm
arises very early and before the closure of the blastopore. The epiblast
is very early divided into two layers, the outer of which takes no share
in the formation of organs, and may be, perhaps, compared to the skin
of a larval Annelid; the inner layer may be spoken of as the formative
epiblast. In the central nervous system the transient giant ganglion-
cells may be distinguished from the ciliated groove which forms the
floor of the primitive central canal. ‘The roof of the fore-brain is very
thin both in embryo and adult; it 1s non-nervous and epithelial in
character, as in Marsipobranchs, Teleostei, and other Ganoids.
Behind the anus the spinal cord is for some time solid.

The larval suckers are developed very early,in the form of a number
of closed spherical sacs, a part of the wall of which is thin and soon
ruptured. The functional suckers are composed of two sorts of cells—
long, glandular cells with hyaline, slightly granular contents and a
nucleus lying near the inner end of the cell, and supporting cells with
the nucleus in the middle of the cell.

The first branchial cleft is formed long before the others and before
hatching; the pneumatoceele arises at a very early period and long
before hatching ; it is a fold of the neural median hypoblast and grows
backward in length, apart from connection with the alimentary canal.
The somites, which are at first solid, are long and narrow; the inner
wall of the somites gives rise to muscle, and most of the outer wall is
converted into pigmented connective tissue. The pronephros is formed
as a solid evagination of the mesoblast; it probably fuses with the
epiblast; at any rate a solid segmental duct is formed, probably from the
inner epiblast layer. Three funnels seem, as a rule, to be formed on
each side of the body, but the most posterior of them disappear, the
others persisting throughout the larval period.

In conclusion, the author calls attention to a transient and larval

* Proc. R. Phys. Soc. Edinb., ix. (1888) pp. 407-12.
~ Proc. Roy. Soc. Lond., xlvi. (1889) pp. 108-118.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 623

nervous apparatus in Lepidosteus and certain other Ichthyopsida. The
presence of the giant ganglion-cells in the embryo has already been
referred to; in all the cases examined they occupy the same typical
position in the extreme dorsal or neural border of the spinal cord.
When a series of horizontal longitudinal sections are made these cells
are found to form a double row which reaches from the termination of
the hind-brain to the posterior limit of the central nervous system.
They are the first cells in the embryo which develope ganglionic
characters and they are fully developed in young embryos long before
the remaining cells of the nervous system become ganglionic. The cells,
which are multipolar, are arranged bilaterally, and there must be several
hundreds of them. They become all shut out of the central nervous
system; these processes are either withdrawn or cut off, and their
poles present a curious stumpy appearance. The cells persist for a
long time, lying outside the cord, just over the posterior fissure. They
finally undergo a series of changes corresponding exactly to that
degeneration and death of nerve-cells which pathologists term simple
atrophy. It is very significant to notice that the forms in which they
normally occur are, without exception, oviparous. The author thinks
that Kleinenberg was quite right in his suspicion that the giant cells
described by Mayer might be analogous to certain subumbrellar ganglion-
cells in the larva of Lopadorhynchus, which “ introduce ” the development
of the ventral cord; just as in that Annelid, the development of the
vertebrate central nervous system would appear to have been initiated
by a larval nervous apparatus outside the same.

Spermatogenesis in Mammals.*—Herr G. Niessing finds that the
general results of his investigations into the spermatogenesis of
Mammals may be thus summed up. The seminal canaliculi of sexually
mature Mammals contain only one kind of cell, and these give rise to
the spermatozoa. The cells are arranged in families which consist in
the resting-stage of three generations, and are disposed in columns.
The oldest member of a family is the stem-cell, on which follow
centripetally the mother and daughter-cells. When the testis passes
into the active stage there is first an alteration in the form of the
daughter-cells. Their nucleus passes to the peripheral cell-wall. All
the chromatin becomes collected in the anterior half in such a way that
it is thickest in the equatorial plane which divides the two halves.
The nucleus begins to be constricted behind the equatorial plane, the
anterior part gradually taking on the form of the head of the
-spermatozoon, while the part devoid of chromatin becomes colourless
and presents in its interior the filament; this traverses the nuclear
membrane and becomes longer and longer. The altered nucleus
generally becomes separated in this form from the cell-body ; the
cylinder narrows continually around the later median-piece and produces
the spiral filament of this median piece, which appears shortly before
maturation. The tail which, by the aid of suitable reagents, may be
shown to consist in its anterior part of a number of very fine fibrils,
arises from the nucleus only. The whole of the spermatozoon is
consequently formed from the nucleus only.

After the metamorphosis of the daughter-cells spermatogenesis com-
mences in the mother-cells and then in the growing mother-cells.
Spermatogenesis is effected, therefore, in three stages, and the stem-cells

* Verhandl, Phys, Med. Gesell. zu Wiirzburg, xxii. (1889) pp. 35-63 (2 pls.)

624 SUMMARY OF CURRENT RESEARCHES RELATING TO

as such take no part in it. The spermatozoa of the second and third
stages remain as bundles in the protoplasmic mass arising from the
altered cells, and lie among the neighbouring families; with the empty,
folded mother-cell-membrane they form the spermatoblasts of v. Ebner.
The spermatozoa are pushed out by the extension of the neighbouring
cell. After the spermatozoa of the third stage are completed, the cell-
families become regenerated from the stem-cells.

Embryonic Cell-division.*—The most important results of Herr
E. Schwarz’s investigations into cell-division in the embryo are :—
(1) The nucleus of cleavage-cells is a radial, uniaxial, ‘“‘ heteropolar ”
structure. (2) The poles of division are separately laid down; the axis
of division is perpendicular to the nuclear axis; the planes of division
are symmetrical, and the succeeding planes of division, as well as the
axes, are perpendicular to one another. (8) The chromatin-structures
are well-developed loops, the number of which may be twenty-four.
(4) The nuclear spindle consists of two kinds of achromatic bundles of
fibres, both of which arise from the nucleus, and both parts pass into
daughter-nuclei. (5) The chromatic daughter-loops each form nuclear
elements with the achromatin which belongs to them, and by their union
the daughter-nuclei are formed. (6) Direct division does not obtain
either in the cellular or in the plasmodial portion of the germinal disc.

B. Histology-f

Structure of Nerve-fibres.{—Prof. F. Leydig thinks it opportune to
direct attention to some of the conclusions to which he has been led
with regard to the structure of nerve-fibres. He has already given
reasons for believing that the nerve-fibres of Annelids and Arthropods
are better called tubes, and that they consist of a spongioplasm enve-
loping a hyaloplasm, the latter being the true nervous material, and the
former a supporting network.

Among Vertebrates the non-medullated trunks of the olfactory nerve
have been examined in the Salamander and the Cat, and it has been
found that the “fibrils” are parts of a hollow system which is traversed
by a fine network. The author has pointed out that the more essential
constituent of a nerve—the material found in the ducts, which is pro-
bably of a semifluid nature—has been left out of consideration. Medul-
lated nerves have been chiefly examined in Hyla and Rana; when
cross-sections of these, preserved in chromic acid, were examined, the
nerve-fibres were seen to be tubes filled with a clear substance; this last
is traversed by lines of network which call to mind what have been seen
in the nerve-tubes of Invertebrates. The recent work of Joseph, who
has made more extensive observations on Vertebrates, substantiates the
Souter Vs of Prof. Leydig. Retzius, also, in essential points supports

eydig.

The recognition of the fact that in the minute structure of ganglionic
spheres and of nerve-fibres we have to distinguish a supporting substance
(spongioplasm) from an inclosed homogeneous material (hyaloplasm
or true nervous substance) is closely connected with the results which
the author has obtained with regard to muscular tissue. There, too, we

* MT. Embryol. Inst. K. K. Univ. Wien, 1888 (1889) pp. 30-73 (2 pls. ).
+ This section is limited to papers relating to Cells and Fibres.
+ Biol. Centralbl., ix. (1889) pp. 199-204.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 625

have a framework which is firmer than the inclosed homogeneous fluid
material which is regarded as the true contractile substance.

Peripheral Nervous System of Amphioxus.*—Dr. R. Fusari has
used in the study of the peripheral nerves of Amphioxus the chloride of
gold and potassium method recommended by Golgi; he has been able to
demonstrate the presence of a sympathetic nervous plexus and of
branchial nerves. A branch of the dorsal spinal nerves divides, when
it reaches the peritoneum, into two branches; one branch, the sym-
pathetic, is distributed to the eritoneum itself; the other passes upwards
and comes into relation wit. the branchie.

By a careful study of the details of the cutaneous nerves the author
has been able to find the cause of the divergences of opinion which have
been expressed regarding them. The arrangement differs in different
regions; on the skin of the back and the lateral regions it is quite
exceptional to find anastomoses between two nerve-trunks, while on the
skin of the abdomen they are so numerous that we may almost say that
this region forms a true plexus. In the latter, also, there are ganglionic
cells in the nodal points, and there are small ganglia formed of two
nerve-cells. The final ramifications of the cutaneous nerves are very
delicate fibrils, which, in chloride of gold preparations, appear to end
freely. In very fine sections some filaments may be seen to traverse the
cuticle which supports the epidermal cells. The author agrees with
Langerhans in believing that there is a direct connection between the
nerve-endings and the epithelial cells.

The branchial nerves may be seen to ramify on the external membrane
which invests the branchial apparatus; the plexus thus formed is very
delicate at some points, and has a general resemblance to those which
are often found among the pseudopodia of Amabe. Two types of
ramification are distinguished in the sympathetic branches.

With regard to the first two pairs of nerves which have by some
authors been regarded as comparable to the fifth pair of cranial nerves
in other vertebrates, in consequence of their possession of what have
been considered to be ganglia, the author states that these bodies are
formed of one to four cells, from which one, two, or even three nerve-
fibres are given off; they may consequently be regarded, in correspond-
ence with the views of several anatomists, as peripheral ganglia.

Role of the Accessory Nuclear Body in Secretion.t—Herr G.
Platner has investigated the histology of secretion in the pancreas of
chelonians, lizards, snakes, and amphibians, comparing the phenomena
there observed with those seen in the Malpighian tubes of insects.
Accessory nuclear bodies (Nebenkerne) are constant in the pancreas of
reptiles and amphibians and in the above-mentioned tubules. With the
appearance of secretion-globules in the protoplasm, a remarkable nuclear
activity is associated. By a process of nuclear budding, not to be
confused with division, an accessory body is formed, which seems to be
an eliminated surplus of nuclear material, and to have a genuine
secretory significance. In the secreting cells there may be only one
accessory body or several; according to their age these exhibit more or
less trace of nuclear characteristics; finally they undergo retrogressive
metamorphoses and disappear.

* Arch, Ital. Biol., xi, (1889) pp. 237-42.
+ Arch. Mikr. Anat., xxxiii. (1889) pp. 180-92 (1 pl.).

626 SUMMARY OF CURRENT RESEARCHES RELATING TO

7y. General.

Zoology of Afghan Delimitation Commission.*— Dr. J. E. T.
Aitchison has issued the reports by various specialists on the animals
collected by him when attached to the Commission. 290 species belonging
to 210 genera, of which 32 species are new, were collected.

Mollusca.

Anatomy and Life-history of Australian Mollusca.j—The Rev. J. E.
Tenison-Woods has made a study of the Mollusca peculiar to Australia.
He considers that, though not separated in an extraordinary way from
Molluscan provinces elsewhere, Australia is entitled to be considered a
true Molluscan province, with peculiar features; these characters are
more strongly manifested in proportion as the coast-line is followed to
the south: the tropical fauna of the Indian Ocean is extended in many
respects far into the extra-tropical portions of the Australian seas. The
sense-organs in the tegmentum of the shell, which were first discovered
by Prof. Moseley in several genera of Chitonide, are found in many
genera of both bivalves and univalves, such as Trigonia, Arca, Venus,
Ostrea, Patella, Cerithiwm, Turbo, &c. In two species of Trigonia the
development of the eyes strongly resembles that of the ommatidia of
Insects, with which the sense-organs are associated. In connection with
these are large ganglia and dependent nerves which are found in the
substance of the shell of both bivalves and univalves. The calcareous
opercula of some species contain nerve-ganglia and sense-organs, as do
probably the chitinous opercula also, to a small extent. The ganglia in
the shell-substance are so much larger than any nervous tissue in the
softer parts of the animal, that they are apparently the main sources
of nervous influence; these ganglia suggest from their position and the
multiplicity of sense-organs that they are really cerebral gangha. The
bivalves examined will, if this is so, be seen to have been erroneously
described as acephalous; they are, if anything, better endowed with a
head and brain structure than some univalves. In the mantles of both
bivalves and univalves eyes have been found, as well as on the dorsal
papille of some species of Onchidium.

In following the life-history of young oysters it was found that the
ova are nursed in the gill-chambers of their parent, a fact which may
have an important influence upon their cultivation. A similar arrange-
ment has been found to exist among certain species of Unio, Siphonaria,
Patella, and Acmza. In very young Siphonaria the lobe of the mantle
in front of the head was found to be covered with from 80 to 90 minute
spherical and highly refractive bodies which seem to be sense-organs
and may have visual powers.

Tf all the new facts described in this remarkable paper should be
shown to be exactly reported, there will be no doubt that the author
deserves the prize awarded for it by the Royal Society of New South
Wales.

Eyes of Mollusca.t—Herr J. Carriére has a review of the recent
works of Patten and Rawitz on this subject; as to the former he uses
some very hard words, and since the memoir is in many points one in
which statements are directly traversed, we will content ourselves with
calling attention to it here.

* Trans. Linn. Soc. Lond., v. (1889) pp. 53-142 (J pls. and 2 maps).
+ Journ. and Proc. Roy. Soc. N. 8. Wales, xxii. (1888) pp. 106-87 (12 pls.).
+ Arch. f. Mikr. Anat., xxxiii. (1889) pp. 378-402 (1 pl.).

ZOOLOGY AND BOTANY, MIOROSCOPY, ETO. 627

B. Gastropoda.

Secretion of Sulphuric Acid by Marine Gastropods.*—Dr. R.
Semon has experimented on the chemical and mechanical characters
which protect many animals against the hunger of their neighbours,
and has directed his attention especially to the abundant presence of
spicules. In this connection he was led to observe how various
“ specialist” gastropods, e.g. Doliwm galea, Tritonium nodiferum, and
Aplysia, devoured Echinoderms in spite of their calcareous deposits.
Now these and many other marine gastropods have for long been known
to exude a fluid rich in free sulphuric acid. The possible uses of this
secretion are discussed, and the author concludes from his observations
that it plays a preliminary part in digestion, changing the carbonate in
the favourite food into readily pulverized sulphate of lime, and thereby
removing the obstacles in the way of such diet.

Purple of Purpura lapillus.;—M. A. Letellier finds that the purple-
forming band in Purpura lapillus is made up of a secreting epithelium
formed of ciliated cells, some of which are alone purpurigenous, while
most merely produce mucus. The purple material is produced by three
substances, one of which is yellow and non-photogenic, while the two
others become blue and carmine-red under the influence of the rays of
the sun. After giving a careful chemical and crystallographic account,
the author expresses his opinion that the purple is produced by a true
chemical reduction. The function of this body, which is most abundant
during the breeding season, is comparable to the castoreum of Castor,
as it seems to bring about the congress of individuals for the purposes of
reproduction.

Nudibranchiata of Liverpool District.{—Prof. W. A. Herdman and
Mr. J. A. Clubb have a second report on the Nudibranchiata of the
Liverpool Marine District. Dendronotus arborescens was found to vary
considerably in abundance at different periods of the year. The authors
have carefully studied its anatomy, and are able to add to or correct the
statements of Alder and Hancock and of Bergh. They did not find any
trace of prolongations from the liver extending actually into the rhino-
phores and the dorsal papille; the correction of the error is due to the
use of thin serial sections. In the sections of the cerata themselves
they find large spaces in the mesoderm containing blood-corpuscles ;
these run, in the main, longitudinally; they occasionally branch, and
they open into innumerable minute lacune in the mesodermal tissues, all
of which here and there contain blood-corpuscles. There is a good deal
of pigmented connective tissue and ramifying threads of a brownish
colour; these frequently give rise, in a surface view, to the appearance of
a dark-coloured granular central cecum, such as that figured by Bergh.
There are also to be seen masses of large distinctly nucleated cells lying
in meshes of fibrous connective tissue; these are possibly mucus-secreting
glands, and occur chiefly in the smaller branches of the cerata.

The upper end of each dorsal papilla of Holis is occupied by a sac
containing a large number of thread-cells; this sac is evidently an
invagination of the ectoderm, and it communicates with the exterior by
a small but perfectly distinct and clearly bounded aperture at its apex,

* Biol. Centralbl., ix. (1889) pp. 80-93.
+ Comptes Rendus, cix. (1889) pp. 82-5.
$ Proc. Biol. Soc. Liverpool, iii. (1889) pp. 225-36 (1 pl.).

628 SUMMARY OF CURRENT RESEARCHES RELATING TO

through which the thread-cells are sometimes found protruding. The
hepatic coecum occupying the greater part of the dorsal papilla reaches
nearly to the lower end of the sac containing the thread-cells, and in
several of these sections the authors saw a tube with muscular walls
leading from the base of the cnidophorous sac and opening into the
apex of the hepatic cecum by a small terminal aperture; this last is
surrounded by a distinct sphincter muscle, so as to allow the lumen of
the hepatic cecum to communicate with the cavity in which the thread-
cells lie, and therefore with the exterior when the sphincter is relaxed.

Anatomy and Development of Renal Apparatus of Pulmonate
Gastropods.*—Herr T. Behme finds that there are some terrestrial
pulmonate Gastropods which have no secondary ureter to their kidney ;
such are Helix pulchella, Buliminus pupa, and others. The kidney,
however, agrees so closely with that of a Limnzxa that we may assume
the great probability of their developmental history being similar. On
the other hand this history strengthens the view of von Ihering as to
the origin of the secondary ureter in his so-called Nephropneusta. The
kidney at any early stage of embryonic life opens with the primordial
kidney directly to the exterior; later on it opens by a primary ureter at
the base of the lung-cavity into an open groove which passes to the
respiratory cleft; this groove is formed by the walls of the pulmonary
chamber. The primary ureter becomes converted into the secondary
kidney, and, as the groove in the lung-cavity gradually becomes closed
from behind forwards, the ureteric apparatus is completely formed.
Hetia pomatia which, so far as its ureteric apparatus is concerned, agrees
with the most highly organized Pulmonata, also exhibits during develop-
ment all the lower stages in the development of the excretory apparatus ;
these lower stages are retained throughout life in various other species.
We are, consequently, led to conclude that, so far as the renal apparatus
is concerned, the families and species with incompletely developed
secondary ureters remain at a lower grade; the lowest is seen in those
forms whose kidneys are emptied by means of a primary ureter.

The value of these characters from a systematic point of view can

only be tested when the comparative anatomy of other organs has been
made out.

Reproductive Organs of Aplysiz.t—Sig. G. F. Mazzarelli describes
the anatomy of the reproductive organs in the Aplysize of the Gulf of
Naples. The hermaphrodite gland, large but compact; the “small
hermaphrodite duct” varying in its details in different species; the
albumen gland and the associated complex nidamental organ; the
“large hermaphrodite duct ” (vagina of Delle Chiaje, uterus of Meckel)
are described at length. The spermatic bursa is independent of the
vagina, and is in communication on one hand with the seminal vesicle
by means of the vas deferens, and on the other hand with the penis by
the spermatic duct. It is simply a second seminal vesicle. The
spermatic duct and the penis are then described at length. The

complex relations of the different parts are illustrated in a diagrammatic
figure.

* Arch. f. Naturgesch., lv. (1889) pp. 1-28 (2 pls.).
t Zool. Anzeiger, xii. (1889) pp. 330-7 (1 fig.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 629

Molluscoida.
a, Tunicata,

Alternation of Generations in Salpe.*—Dr. O. Seeliger discusses
the problem of the origin of alternation of generations in Salpx. He
reviews the various statements and interpretations of the facts, especially
those of Todaro, Brooks, Salensky, and Ulianin, but is dissatisfied with
all. The alternation has arisen from an original ‘“ hypogenetic” process
in the following way. A portion of the hermaphrodite system became
degraded and gave off buds, with which processes of the parent ectoderm
and endoderm co-operated. The remaining portion of the reproductive
organ in the parent organism retained its normal function. In
Pyrosoma, the forms produced by budding retained both modes of multi-
plication.

At a further stage, not a portion merely, but the whole reproductive
organ of the original solitary form was used up in budding. An asexual
generation thus arose, as at present exhibited in Salpe. At the same
time, with increasing dimorphism of generations, the asexually produced
individuals lost the power of budding.

In Pyrosoma, the stolo prolifer forms only about six individuals, each
of which has in the ovarian strand one large ovum and a considerable
number of undifferentiated reproductive cells. In Salpa, on the other
hand, the sfolo prolifer of the solitary form gives off many hundred
closely apposed buds, in which only a few cells are found in the ovarian
strand able without special delay to form the hermaphrodite system. In
the chain Salpa there are no further cells, as there are in Pyrosoma, in a
position to become the mesoderm of fresh buds. Furthermore, in the
close disposition of the Salpa buds, there is neither space nor nutrition
for another generation of buds, even if ectoderm and endoderm should
still retain the embryonic character which would admit of their taking
part in a budding process. |

B. Bryozoa.

Polyzoa of the Voyage of H.M.S. ‘ Challenger.’t—Mr. A. W. Waters
has prepared a short supplementary report on the Polyzoa, in which he
adds particulars of various structures and organs not previously noticed.
The most interesting discovery appears to be that of the presence of a
common parenchym cord surrounding the zocecia of Retepora columnifera.
Mr. Waters thinks that we must not be satisfied merely with the shape
of the operculum, but we must give special attention to the way in which
it is attached and articulated, and the connection through the rosette
plates must be more studied. Too much attention seems to be attached
to peristomial characters.

Bryozoa of New South Wales.{—Mr. A. W. Waters describes a
number of incrusting species of Bryozoa obtained off Green Point, Port
Jackson. Some of these are new, and others, being represented by better
specimens than heretofore, are now more fully described.

Reproduction of Ctenostomatous Bryozoa.s—M. H. Prouho gives
an account of some observations on the reproduction of Alcyonidium

* Jenaische Zeitschr. f. Naturwiss., xxii. (1889) pp. 399-414.

+ Reports of the Voyage of H.M.S. ‘Challenger,’ xxxi. pt. Ixxix. (1889) 41 pp.
(3 pls.). $ Ann. and Mag. Nat, Hist., iv. (1889) pp. 1-24 (3 pls.).

§ Comptes Rendus, cix. (1889) pp. 197-8,

630 SUMMARY OF CURRENT RESEARCHES RELATING TO

albidum, A. duplex (sp. n.), and Pherusa tubulosa. The ova of the first
of these escape into the perivisceral cavity, whence they.are severally
projected to the exterior by the so-called intertentacular organ, the
function of which has been so much discussed. In A. duplex the phe-
nomena are more complicated and more interesting. When the sexual
elements are about to be developed, the zocecium is occupied by a
polypide, without any intertentacular organ, and a cellular mass, which
is destined to form the spermatozoa, appears by the wall of the gastric
cecum. Towards the aboral extremity of the same zocecium there is
formed a second polypide, on the funiculus of which young ova appear.
The older polypide appears to be the male, the younger the female.
The former soon begins to degenerate, and leaves the brown body and
the mass of spermatozoa; the female polypide is now seen to be provided
with an intertentacular organ, which conveys the ova to an invaginated
sheath, where development is effected as in a marsupium. Pherusa, like
Membranipora and Flustrella, has a bivalved larva.

Arthropoda.

Ancestors of Myriopods and Insects.*—Prof. B. Grassi has an
elaborate essay on the comparative anatomy of the Thysanura, together
with some general considerations on the organization of Insects, The
external skeleton and the segments are first dealt with; there are three
thoracic segments, and ten abdominal; those authors are incorrect who
regard the anal valves as representing a segment; like the Thysanura,
the embryos of higher insects, e. g. the bee, have ten abdominal segments.
The author does not think that the epicranial suture is of any assistance
in determining the number of cephalic segments.

The disposition of the muscles does not afford any support to the view
that the Thysanura have lost wings which they once had; on the other
hand, we may say that just as they are provided with lateral prolonga-
tions which might well be developed into wings or gills, so are they in
the same way provided with muscles which would enter into the service
of suchorgans. Although the musculature of these low insects is divided
into dorsal and ventral portions and into lateral areas it has no intimate
relations with that of Peripatus.

The respiratory system is treated of in the third section. The most
primitive arrangement seems to be found in Japyx solifugus, where
there are eleven pairs of stigmata, four thoracic, and seven abdominal.
Campodea has only three pairs of thoracic stigmata, the third, as well as
the last seven of Japyx solifugus, being wanting. In J. Isabell there
are two thoracic and seven abdominal pairs, and the same is the case
with Machilis. The Lepismide have probably three thoracic and seven
abdominal. The fact that J. solifugus has four pairs of thoracic stigmata
points to the conclusion that the original position of the thoracic stigmata
was not segmental. The conditions found in the Lepismide are retained —
by the Blattide, and by the Orthoptera generally, and they are also
reproduced in the embryo of the Bee. The author’s observations tend
to modify considerably the fundamental conclusions of Palmén—for
example, we must accept Gerstaecker’s view that a large number of
Insects have still three pairs of stigmata and not two; there is a direct
passage between the conditions which obtain in the Thysanura and in

* Atti R. Accad. Lincei—Mem., iy. (1887) pp. 543-606 (5 pls.). Arch. Ital.
Biol., xi, (1889) pp. 1-11, 291-337, 389-419 (5 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 631

the Orthoptera; as to the latter point, much supporting evidence is
afforded by the trachee. The same is true of the bee, for the embryo
passes through a stage which recalls that of Machilis and Campodea, and
then becomes very like that of the Lepismide. The author considers
that the formation of the apodemes must have been cotemporaneous
with that of trachee, for both start as infoldings of the hypodermis.
When this infolding is filled entirely, or almost entirely, with cuticle
(chitin) secreted by the invaginated hypodermis, we have an apodeme,
but when the cuticle only invests its free surface, we have a small canal
lined with cuticle, that is to say, a trachea with its stigma. Further,
there must be a very close connection between the formation of apodemes
and of the tracheal system from the physiological point of view, for the
thickening of the cuticle requires the formation of new respiratory
organs ; the thickening of the cuticle allows the musculature to develope
itself more largely, and the musculature, in its turn, tends to produce
depressions of the hypodermis, and of the cuticle to which it may become
attached ; it tends, in fact, to give rise to apodemes.

The nervous system and sensory organs are next discussed; this
system and the eye of the Thysanura are of the same type as those of
other insects, but are comparatively more simple. The nervous system
of Campodea is still closely connected with the hypodermis, and at
certain points (where the ganglia attain their maximum size) it is
altogether connected with it, there being no dividing gangliolemma; in
Japyx and others this gangliolemma consists of a simple layer of flattened
cells, and in Japyx there is a comparatively large lacuna between the
gangliolemma and each ganglion.

The intestine becomes more complicated as we pass from Campodea
to Lepisma, the latter resembling the true Orthoptera by its well-
developed gizzard, the curves of the median and posterior intestine, the
diverticula of the rectum and the salivary apparatus. Prof. Grassi
believes that the Malpighian tubules are homodynamous with the
stigmata and corresponding trachee.

The dorsal vessel is exactly like that of other Insects; no alar
muscles were discovered in any of the Thysanura, though they are
known to exist in the Collembola. In several, and particularly in
Machilis, there are occasional traces of a vessel uniting the dorsal vessel
with the intestine. Anatomical and embryological facts seem to establish
the homology of the dorsal vessel of Insects with that of Annelids.

The Thysanura have, as a rule, an oviduct (uterus), a vagina, and a
bursa copulatrix. The first is absent in Campodea only; Machilis has
no bursa and appears to be simpler than its allies. The arrangement
which obtains seem to support the views of Palmén as to the double
nature of the genital ducts.

After a somewhat detailed account of the generative apparatus the
author concludes that in the ancestors of Arthropods the sexual products
were, as in certain Annelids, eliminated by means of the segmental
organs ; later on one of the two pairs was closed; in the secondary
sexual organ of Campodea there exist signs of the closed pair.

The appendages, especially the gnathites, are discussed at some
length ; all the Thysanura have a galea (external lobe of maxilla); this
is a character which is repeated only by the Orthoptera and some
Neuroptera, and is not found in any other insect.

Passing to systematic problems Prof. Grassi asks if the order of
the Thysanura is a natural one. He thinks it is, and he places it under

632 SUMMARY OF CURRENT RESEARCHES RELATING TO

the ‘‘superordo Orthoptera s. lat.,” and divides it into two suborders;
the simpler, or that of the Entotrophi, contains the two families
Campodeade and Japygide, and the Ectotrophi, the Machilide and
Lepismide. In the former the buccal apparatus is partly retained within
the head and partly fused into a lower lip; in the latter there are
external gnathites and the lower lip is deeply divided.

The Entotrophi may have eleven, the Ectotrophi never have more
than ten stigmata ; in the former the Malpighian tubes are rudimentary,
while they are well developed in the latter. These and other characters
which are duly enunciated justify the division into these two suborders.

The next question discussed is what relations have the Thysanura
with the different orders of insects proposed by Brauer and with the
Collembola. The author regards the Thysanura as the lowest order of
Orthoptera (sens. lat.), and the other Orthoptera as being derived from
Insects allied to them.

Thysanura | Endotropha
Thysanura Ectotropha
Lb be
oO 2 eae
Hed =: = a iS) a
B 6 5 ® 5B =
aS. JS eee
e # 28) ee
gL Be ike
3

The superorder of Orthoptera might be called the Protentoma and
all other Insects the Metentoma. The author regards as the most
important result of his researches the full justification of the hypothesis
that the Thysanura are the most primitive Insects that we know, at
least in the greater number of their organs. Further researches on the
Collembola will probably lead to their being placed with the entotrophic
Thysanura. Prof. Grassi’s views as to the relationship which obtains
between the various groups of the Arthropoda are shown in the following

table :—
Arachnida arthrogastra (Araneida) Symphyla (Myriopoda)
Pecilopoda ds
Thysanura (Protentoma or

~~ Tee Insects in general)

Phyllopoda (Crustacea)

Peripatus

4 Chilopoda

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 633

a, Insecta.

Insects supposed to be distasteful to Birds.*—Mr. A. G. Butler,
who keeps a large number of birds, has observed that no insect in any
stage was ever refused by all the birds; what one bird refused, another
would eat. He is of opinion that metallic colours are not a source of
protection to birds; a bird knows nothing of the nature of metal, but
whatever is brilliant and shining he makes for at once to see whether it
is good to eat. It appears to him that certain species of Lepidoptera
and of other insects may become abundant in certain years owing to
the temporary scarcity of their particular enemies, but they never enjoy
perfect immunity from destruction. The spider-like appearance of the
larva of Stuuropus is not a protection against birds, for, if there is any-
thing that all insectivorous birds love it is a spider. The sting-like
tentacles of the larva of Dicranura vinula are Heme no protection ;
three young nightingales never hesitated for a moment to use the
tentacles as handles to assist them in knocking the life out of the cater-
pillar before devouring it.

Histology of Insects.;,—Dr. C. Schiffer first treats of the ventral
glands in the larve of Lepidoptera. As seen in Hyponomeuta evony-
mella the ventral gland is a tube which commences in the metathorax,
which is continued forward to the anterior edge of the prothorax where
it opens on a conical projection which is provided with two retractors.
It is surrounded by a rich system of trachez arising from several large
trunks. It is distinctly divisible into an anterior and a posterior
portion. A similar organ is found in Harpyia and in Plusia gamma,
and it may, therefore, be reasonably supposed to be widely distributed
among the Lepidoptera. It appears to be derived from a simple
invagination of the hypodermis.

The second subject dealt with is the site of blood-formation in the
larve of Insects; in Hyponomeuta evonymella the blood is found in
the fat-body (in its widest sense) and in the matrix of the trachee.

In Smerinthus, Ocneria, Gastropacha, Pieris, Vanessa, and Harpyia,
the cells which form the blood-forming tissue are differentiated during
the embryonic development of the fat-body. In Lyda erythrocephala the
site of origin of the blood is widely distributed through the body; while
in Hyponomeuta the tissue is only found at the rudiments of the wings,
it has in Lyda the form of cell-aggregates which are scattered through
the whol¢ thorax and abdomen of the caterpillar, though always in
more or less close connection with the fat-body. In the larve of Musca
the fat-body is chiefly formed from the tracheal matrix, while the
hypodermis gives rise both to blood-corpuscles and to cells of the fat-
body ; the latter possibly give rise to the fat-body of the adult.

The chief point brought out by the author is the genetic connection
between the fat-body and the blood corpuscles in the first place, and then
of the ectoderm (hypodermis and tracheal matrix) on the other side, and
the fat-body and blood corpuscles on the other. The last may, in the
nomenclature of v. Wielowiejski, be called the blood-tissue. The chief
function of the fat-body is to take up and give out again nutrient sub-
stances, so that the proposed name is physiologically as well as morpho-

* Ann. and Mag. Nat. Hist., iv. (1889) pp. 171-3.
t Zool. Jahrb, (Abth. f. Anat.), iii. (1889) pp. 611-52 (2 pls.).

1889. 2Y

634 SUMMARY OF CURRENT RESEARCHES RELATING TO

logically correct. Analogous cases may be cited from Kiikenthal’s
observations on lymphoid cells in Annelids and Semon’s studies on
Holothurians. .

In the third and last place the author describes some points in the
development of the wing of Lepidoptera. The eversion of the wing in
the passage of the larva into the pupa stage is effected by blood-pressure.
In the young pupal wing there are, in addition to the large trachee,
blood-ccrpuscles which are more or less charged with nutrient mater al.
It is important to note that the matrix of the trachc gradually dis-
appears altogether, and that in the wing of the imago even the very
d:l.cate intima can no longer be found. Scales and hairs are formed on
the first day of the pupal stage; both structures are, in general terms,
outgrowths of greatly magnified hypodermis cells. The mother-cells of
the hairs are much larger than those of the scales.

The fusion of the wing membranes begins at a very early stage, and
in a peculiar manner. Clefts appear in the hypodermis owing to the
cells increasing in length, and separating from one another. A con-
tinuous m mbrane formed of protoplasm is present, which may be called
the ground membrane of the epithelium. Both blood-corpuscles and
blood fluid make their way through this membrane. Between the
two wing membranes is a system of pillars formed by the hypodermis.
The clefts in the hypodermis function as blood-spaces, and the fluid
clearly serves to nourish the hypodermis of the wing. ,

Later on, the two wing membranes are, in consequence of the con-
siderable growth of their surface, arranged in a number of small folds.
The median membrane formed by the fusion of the two is absorbed so
that the wing is traversed by a number of thin pillars which connect the
two membranes. In the imago the hypodermis of the wing is reduced
in a extraordinary manner, while the mother-cells of the scales have
almost completely disappeared. Trachez too are no longer to be found.
The cuticle «f the wing does not appear till a comparatively late stage,
and its appearance sets a limit to the growth of the suiface of the wing.
The wine-ribs, as Semper calls the tubes which accompany the trachez
in the veins of the wings, are, the author has observed, connected with
the tracheze. A rib, when complete, has in cross section the form of a
tube which is generally cylindrical, and is lined by a very thin chitinous
intima, which carries delicate tracheal branchlets. In the ribs there is
a central cord which in longitudinal section exhibits a distinct longi-
tudinal striation; this cord appears to be excreted by the cells of the
wall of the tube, and does not appear to be, as Semper has supposed,
nervous in nature. =

Before the wing gets its characteristic marking, owing to the
differentiation of the scales, it is coloured red by a pigment deposited
in the cells of the hypodermis. The characteristic marking appears in
a very short time, and is, therefore, difficult to investigate. The study
of these markings has not as yet enabled the author to make out
definitely the phylogenetic development of colour-pattern in the way
effected by Weismann for caterpillars. and by Eimer for Vertebrates; a
few points, however, appear to be indicated.

Number of Polar Globules in Fertilized and Unfertilized Eggs
of Bees.* — Prof. F. Blochmann has recognized the importance of

* Morphol. Jahrb., xv. (1889) pp. 85-96 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 635

determining the number of polar globules in ova which, without being
fertilized, become developed into male animals. For this purpose, as
for some others, the egg of the Honey Bee is well adapted, and it is
here always easy to keep the unfertilized from the fertilized eggs. The
first polar nucleus always remains undivided, as is the case in some
other Insects; in Apis the second polar nucleus often appears to be
divided. The fact that the three nuclei are not, as in some cases, due
to a division of the first nucleus is proved by the position of this nucleus,
which is always found just under the surface of the egg and separated
by some distance from the other two. The female pronucleus soon
becomes vesicular in form, and makes its way to the axis of the egg,
when it becomes converted into a spindle, and by further divisions gives
rise to the nuclei of the blastoderm-cells. The polar nuclei undergo
changes similar to those seen in Musca vomitoria ; they do not, however,
become vesicular in form, but approach one another and are inclosed by
a rather large vacuole of the superficial protoplasm which is free from
yolk. In this vacuole they break up into fine chromatin granules which
are then scattered through the whole cavity of the vacuole. We may
suppose that the contents are, later on, removed from the egg.

In fertilized ova the ovarian nucleus undergoes the same division as
in the unfertilized. The result of the investigation—that the unfertilized
ova form two polar globules—or, more correctly, two polar nuclei by
two divisions of the ovarian nucleus, is confirmed by the results which
Platner has obtained with Liparis dispar.

With regard to the bearing of these observations on the theories of
Weismann, the author says that he thinks it is better to extend the
investigation in all directions, and only afterwards to construct a theory,
instead of basing an extensive speculation on a limited number of facts ;
the speculation, indeed, is only too soon shown to be untenable, as it is
in contradiction to observed facts.

Respiration of the Ova of Bombyx.*—Profs. L. Luciani and A.
Piutti have made an elaborate series of experiments on the respiratory
phenomena in the ova of the silkworm. Respiration is slight during
hibernation ; at the ordinary temperature of 8°-10° C., a kilogramme of
ova produced only about 18 centigrammes of CO, in 24 hours. The
respiratory activity is lessened by lowering the temperature, by desicca-
tion, and by restricting the space. Both cold and drought induce
“absolute latent life,’ when the respiration ceases. During artificial
incubation, with a gradual rise of temperature, there is a regular increase
in the quantity of CO, given off per unit time, till towards hatching the
amount is 259 times greater than that at 0° C. during hibernation. The
respiratory activity also varies with the developmental activity. The
relation of the CO, exhaled to the oxygen absorbed—the “ respiratory
quotient ”—is expressed in a fraction increasing to unity and beyond that
as development progresses. There is therefore in all probability a pro-
duction of less oxygenated molecules and an increasing sum of potential
energy.

Termites.j—Prof. B. Grassi has a preliminary note containing
further information on these interesting insects. He finds that colonies
of Termites annually produce an enormous number of sexually mature

* Bull. Soc. Entomol. Ital., xx. (1888) pp. 69-99.
ft Zool. Anzeig., xii. (1889) pp. 355 -61.

27

bo

636 SUMMARY OF CURRENT RESEARCHES RELATING TO

individuals. Those which become mature in spring get completely
developed wings and then leave the maternal nest to become the true
kings and queens of new colonies; this, however, very rarely happens to
them. Those which become mature in summer copulate and multiply
(complementary kings and queens). The complementary kings die |
before the beginning of winter, so that the queens alone survive; these
cease to deposit eggs in winter and spring, but begin again in May;
they then make use of the sperm which they have kept stored up in their
spermatheca since the preceding autumn. The author does not know
how long the complementary queens may live, but it is probable that
they die when the next set of complementary kings and queens becomes
mature. The various forms of 'l'ermites are exhibited in the accompany-
ing table :—

Termes lucifugus.

1. Youngest larve.

2. Larvee, incapable of 3, ean of 4, Replacement pairs—
reproduction reproduction only present when

14, 15, and 11 are

wanting, or the two

latter are incom-

| pletely represented

| | | | |
5. Larvee 6. Larvee 9. Nymphs 10. Nymphs 11. Replacement pairs
of of

of of —only present
soldiers workers Form I. Form II, when 14, 15, and
| | 4 are wanting, or
7. Soldiers 8. Workers | the two latter in-
~ completely repre-

sented

| |
12. Winged 13. Replace-
forms ment pairs
}

|
14. True king
and queen
15. Complementary pairs.

Abdominal Appendages of a Lepismid.*—-Dr. J. T. Oudemans
gives an account of the abdominal appendages of the little known
Thermophila furnorum. They are found on the seventh, eighth, and
ninth ventral shields, but do not all appear until the creatures are
adult; they appear in order from behind forwards. These processes are
not rudimentary organs and therefore have nothing to do with the
primitive legs. They are found in males as well as in females, but
seem to appear in the latter somewhat earlier than in the former.

Galls produced on Typhlocyba rose by a Hymenopterous Larva.
—M. A. Giard calls attention to the death last October of a large
number of specimens of Typhlocyba rose; further investigation has
shown that they become the prey of a hymenopterous larva which has a
close resemblance to that of Misocampus.

* Zool, Anzeig., xii. (1889) pp. 353-5.
t+ Comptes Rendus, cix. (1889) pp. 79-82.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 637

y. Myriopoda.

Anatomy of Polyxenus lagurus.*—Mr. F. G. Heathcote gives a
description of some points in the anatomy of this Myriopod. The
Malpighian tubes differ somewhat from those of its allies; each tube is
doubled on itself in such a way as to form a great spherical knot, the
greater part of which les in the semicircular chitinous elevations which
are placed at either side of the anus. The nerve-cord shows a greater
resemblance to that of the larval Julus and also of Chilopods than
does the nerve-cord of any other Chilognath with which the author is
acquainted.

The chief interest of this form lies in the resemblance presented by
some of its anatomical characters to the anatomy of Chilopods. It
agrees, indeed, with the Chilognatha in the position of its generative
organs and the duplication of some of its segments, as well as in its
vegetable feeding habits, but it resembles the Chilopoda in the form of
its spermatozoa, which are long and filiform and are contained in
spermatophores, in the general structure of its segments, the legs being
wide apart, and in the differentiation of the ventral nerve-cord. The
peculiar form of the second pair of mouth-appendages and the absence
of stink-glands, with the substitution for them of numerous spines as a
means of defence, are characters special to the genus. Polyxenus seems
to have preserved in its anatomy certain traces of its descent from the
ancestor common to the two classes of Chilopoda and Chilognatha; to
Mr. Heathcote it affords further reason for believing that the Myriopods
are descended from a Peripatus-like form, and as opposing their descent
from the Thysanura.

3. Arachnida.

Structure and Function of Spinning Glands of Araneida.t—Herr
C. Apstein has not, like most of his predecessors, confined his investiga-
tions to Epeira diadema. In the Epeiride he distinguishes five kinds
of glands; the glandule aciniformes are those which consist of a tunica
propria and an epithelium which exhibits in all its parts the same
reaction to staining reagents, whose longitudinal is hardly greater than
their transverse diameter, whose efferent duct has no epithelium but a
thick tunica intima, and which ends in a spool, which is drawn out into
a fine tip. , The glandule pyriformes consist of a tunica propria and an
epithelium, which in its lower parts (or those near the efferent ducts)
stains more deeply than in the upper, whose efferent duct has a thick
tunica intima but no epithelium, and which ends in a spool with a very
small basal and fine short accessory piece. The glandule am pullacese
have a tunica propria and an epithelium, the earlier part of which is
cylindrical, and then forms an ampullaceous swelling; the efferent duct,
which consists of tunica propria, epithelium, and tunica intima, forms a
double fold, and ends in a large spool cut off sharply at its end. The
glandule tubuliformes vary hardly at all in diameter and end in a large
spool. The glandule aggregate havea wide and much-branched lumen,
the efferent duct of which is, in its median part, provided with protuber-
ances filled with cells; their spool is large and has an accessory piece
which draws out toa tip. The glandule tuberose described by Meckel
and by Oeffinger Lave no existence.

* Quart. Journ. Micr. Sci., xxx. (1889) pp. 97-106 (1 pl.).
+ Arch. f. Naturg., lv. (1889) pp. 29-74 (1 pl.).

638 SUMMARY OF CURRENT RESEARCHES RELATING TO

The differences which obtain in the Retitelariz, the Tubitelarie, the
Citigrade, the Laterigrade, the Saltigrade, the Plagitelarize, and the
Territelarie are next fully described.

All the glands consist of a secreting portion—glands in the strict
sense —which also serve as collecting cavities for the spinning material—
and of an efferent duct which opens to the exterior by a spool of varying
size. The true gland consists of a tunica propria and a more or less
high epithelium. The duct consists of a tunica propria, and of a low
epithelium (except in the aciniform and pyriform glands where there is
no epithelium) and of a thick tunica intima. The spinning spools
consist of a basal and an accessary piece. The upper and lower warts
are two-jointed, and the median one-jointed, except in the Mygalide
where there are three and two joints respectively. In addition to the
five glands already enumerated there are also lobate and cribrellum-
glands; these are variously distributed in various groups, and the
Mygalide have pyriform glands only. In the males the number of
tubuliform glands may be less than in the females, or they may be com-
pletely wanting. With the exception of the Mygalidz no Spider has
less than three or more than six kinds of glands.

The author has made a number of biological investigations, the chief
results of which are: the glandule aggregate prepare the so-called
moist filaments from the moist droplets ; the tubuliform glands spin the
ege-cocoon ; the cribrellum-glands prepare the coiled tissue. The
lobate glands prepare the spinning material to catch the prey. The
pyziform glands form the seizing tissue and attach the separate filaments
to firm objects by means of the so-called dise of attachment. ‘The
function of the aciniform and ampullaceous glands is not yet known. It
is possible that several glands may take part in spinning a web round
the prey.

Parasites of Spiders.*—Dr. P. Bertkau communicates some obser-
vations on the occurrence of Mermis in Tarentula inquilina and the
resulting sterility of the host. Worm parasites have seldom been
observed in Arachnids, but the author has occasionally found them in
Salticus formicarius and Tegenaria atrica. In the species of Tarentula
above mentioned a large Mermis, probably M. albicans, was repeatedly
found.

In autumn the mature sexes of this spider are to be found; after
copulation both disappear. The females conceal themselves and lay
eggs; the males die. When mature forms are found in May and June
they often contain a Mermis. Several cases are described, in one of
which the parasite measured 11-3 centimetres. In a male Tarentula con-
taining this parasite the sexual function seemed to have been prevented.
It was caught in May, with palps full of encysted spermatozoa. Bertkau
thinks that copulation had been hindered for some nine months. The
act is followed by death ; the motive comes as usual from the internal
reproductive organs, not from the sperm-laden palps, but the presence
of a parasite may entirely alter the habit.

New Acarid.t—Prof. B. Grassi and Sig. G. Rovelli describe a
peculiar Acarid, Podapolipus reconditus g. et sp. n., an abundant parasite
on the Coleopteron Akis (or Acis) spinosa. The parasite belongs to the

* Verh. Nat. Ver. Preuss. Rheinl., xlv. (1888) pp. 91-2.
+ Bull. Soc. Entomol. Ital., xx. (1888) pp. 59-63 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 639

family Tarsonemide ; the body is segmented ; the mandibles are slightly
developed and stilet-like; trachez arise at the base of the rostrum on
the ventral surface; there are two curious p:ominences, like adhesive
organs, between the first and second pairs of legs ; the first pair of limbs
are clawed; there is sexual dimorphism.

Even the young forms are of two distinct sorts ; in one set the clawed
first pair of limbs and the curious prominences are acquired, but the
three posterior pairs of appendages and the candal sete are lost. These
are females, and acquire sac-like bodies, distended with ova, embryo, and
young forms. Others seem to remain small and less modified, and are
pigmy males. The enigmatical prominences, the dimorphism, and the
extreme degeneration are interesting features in this new Acarid.

€. Crustacea.

Intestine of Decapoda and its Gland.*—Prof. G. Cattaneo has
followed up the researches of Weber, Frenzel, and others, as to the
structure of the intestine in Decapod Crustaceans, and the nature of the
mid-gut gland. In the intestine proper he distinguishes seven strata,
the chitinous cuticle, a layer of cylindrical epithelium, a layer of con-
nective, longitudinal, radial and circular muscles, and an external
connective-tissue layer, but has added little to previous researches. His
experiments on the function of the gland are more interesting, for they
show that it is complex enough to be compared to that of all the
Vertebrate digestive glands taken together. The mid-gut gland thus
seems well to deserve the title he gives it of “ polyenzymatic,” which is
even wider than “ hepato-pancreas.”

Early Development of Blastodermic Layers in Isopoda.{—M. L.
Roule has investigated the early stages in the development of the
blastodermic layers in Asel/lus aquaticus and Porcellio scaber. In the
former fecundation is followed by the radial division of the yolk into a
small number of blastomeres, which, in their turn, divide radially and
tangentially to form a compact planula. The walls of the cells are very
delicate, and the least pressure causes them to disa) pear ; in sections these
walls are not seen and the whole yolk has the appearance of a homo-
geneous mass, hollowed out by vacuoles, in the interior of which are
found the granulations dissolved by the reagents. Later on,a zone of
hyaline protoplasm appears at the pole of the egg, which corresponds to
the anterior region of the embryo; this zone thickens, then seems to
slowly extend itself on the ventral and to rise up again to the dorsal
surface. The zone does not, however, extend by itself or independently
of the yolk. In sections nuclei appear at the periphery of the yolk;
this part then becomes hyaline and the distinction between ectoblast and
mesoendob!ast becomes apparent.

The history of Porcelliv is the same, save that there is no preceding
segmentation ; there is not, in fact, epiboly as one would expect from
Bobretzky’s observations on the closely allied Oniscus.

British Amphipoda.—In the second part of his paper t Dr. Norman
treats of the Leucothoide, Pardaliscide, and Marine Gammaride.
Leucvthoé imparicornis is a new species from Shetland; Lilljeborgia

* Atti Soc. Ital. Sci. Nat., xxx. (1887) pp. 238-72 (1 pl.).

t+ Comptes Rendus, cix. (1889) pp. 78-9.
t Ann. and Mag. Nat. Hist., iv. (1889) pp. 113-41, 3 pls.

640 SUMMARY OF GURRENT RESEARCHES RELATING TO

picta sp. n. is discussed at some length. The new genus Megaluropus
should not be placed, as it has been by Dr. Hoek, among the Parda-
liscidee.

Spermatogenesis in Ostracoda.*—Dr. G. W. Miiller finds that the
mother-cells of the spermatozoa of Ostracods are matured in the middle
of the testicular tubes (Pontocypris) or at their ends (Fresh-water
Cyprids). These mother-cells either migrate as needed, when a testi-
cular tube always contains spermatozoa of the same age and mother-cells
of only two or three sizes (Pontocypris, Cypris compressa), or a large
number migrate during youth and before the formation of the sperma-
tozoa. The mother-cells increase in size from before backwards; in
Cypris dispar, Caudona, and Notodromas we always find spermatozoa and
mother-cells of very various ages and sizes. The number of cells which
divide at one time varies in Pontocypris sp. between three and nine, in
Cypris compressa between three and eight; in C. dispar it is two, and
in Notodromas and Caudona four. Each mother-cell ordinarily gives
rise to four sperm-cells, and only occasionally to three or two.

True spermatogenesis is effected in very much the same way as in
other Arthropods. One or two subsidiary nuclei form a tail-piece which
grows to an extraordinarily great length, and is of a very complicated
structure; the nucleus is either placed quite at the end of the body so
formed (Pontocypris) or near the end (Fresh-water Cyprids). The part
formed by the subsidiary nucleus is divided into a broader and a narrower.
portion or head and tail. As the spermatozoa are variously arranged
in the testis, and as the complicated apparatus of the efferent ducts
require a similar arrangement of all the spermatozoa, it is clear that
some of the spermatozoa must be turned round. In Pontocypris this is
effected by those which go out with the tail forwards, passing into a
cecum, while they, of course, leave with their heads directed forwards.
In the fresh-water Cyprids all the spermatozoa pass into the cecum,
and so are all turned round; those that need to be turned the other way
enter a pyriform enlargement of the vas deferens which lies between the
testis and the cecum.

The spermatozoa consist of the central filament and three bands
which lie beside one another, and are connected with one another along
their whole length; of these the median band is contractile. A con-
tiaction of this band causes the spiral twisting. The investment of
some species is secreted by the spermatozoon itself, while in other cases
it is possible that the investment is secreted by the walls of the vas
deferens. In one case (Pontocypris) at least we can certainly prove that
the investment contracts, and that very strongly; in the fresh-water
Cyprids the contraction is probably slighter. This contraction probably
aids the spermatozoa in escaping from the receptaculum seminis.

New Pelagic Copepods.t—Dr. W. Giesbrecht gives a list of the
pelagic species of Copepoda collected on the voyage of the ‘ Vettor
Pisani’ (1882-5), and by F’. Orsini from the Red Sea. The list includes
63 species, of which 41 are new. The latter are briefly diagnosed.
Nine new genera, Acrocalanus, Calocalanus, Leptocalanus, Clausocalanus,
Ctenocalanus, Spinocalanus, Gaétanus, Undeuchzta, and Euchirella, are
distinguished.

* Zool. Jahrb. (Abth. f. Anat.), iii. (1889) pp. 677-726 (2 pls.).
+ Atti R. Accad. Lincei (Rendic.), iv. (1888) pp. 330-8,

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 641

New Parasitic Copepod.*—Prof. J. Leidy describes a new species
of Chalimus (C. tenuis) found attached to the tail-fin of a Leptocephalus ;
it is considerably less than half the size of C. scomberi described and
figured by Dr. Baird in his work on British Eutomostraca.

Remarkable Crustacean Parasite. t-—Dr. G. H. Fowler gives an
account of a remarkable crustacean parasite allied to Laura and Syna-
goga, and makes some remarks on its bearing on the phylogeny of the
Entomostraca. The name proposed for the new genus is Petrarca bathy-
actidis, as it was found, represented by these individuals, in the mesen-
terial chambers of Bathyactis symmetrica.

The animal is nearly spherical externally and measures 1°5 to 1°8
mm. in diameter. The general relations of the body, limbs, and
carapace are those of a Lepas without a peduncle, with the terminal
penis bent forwards under the thorax, the limbs much reduced, the
mantle not carrying calcareous plates but greatly swollen by the growth
of the internal organs into its substance. The antenne are terminated
by two strong dorsally directed hooks; the oral cone contains a pair of
weak crushing mandibles, and behind it there are six pairs of thoracic
appendages, of which the last five are simple leaf-like flabella; they are
all devoid of hairs or spines. The body is prolonged into a trumpet-
shaped penis slightly bifid at the free end. The epidermis is a single
layer of flattened cells and is covered by a thin chitinous cuticle; there
is no evidence of any calcareous deposit. The lining membrane of the

Copepoda Phyllopoda Ostracoda Ascothoracida Cirripedia

feo
Synagoga Laura Petrarca

Cypridiform larva

Protostraca

* Proc. Acad. Nat. Sci. Philad., 1889, p. 95.
+ Quart. Journ. Micr. Sci., xxx. (1889) pp. 107--21 (1 pl.).

642 SUMMARY OF CURRENT RESEARCHES RELATING TO

hepatopancreas and alimentary canal consists throughout of well-marked
cubical cells and shows no specialization in any particular region.

The nervous system consists of a minute supra-cesophageal mass of
transverse nerve-fibres devoid of nerve-cells—a curious result of the
degraded habit of life—of two circumeesophageal commissures with
nerve-cells, and of a comparatively thick ventral cord well supplied with
cells. No eyes or other sense-organs were recognizable. The animal
is hermaphrodite, and Dr. Fowler was able to make some observations
on the course of spermatogenesis.

Petrarca is much more degraded than Laura; no head region is dis-
tinctly marked off as such, only one pair of mouth appendages is recog-
nizable, the thoracic appendages are much simpler in character, the
abdominal region has almost disappeared, and segmentation occurs only
in the posterior region of the body. Both genera, however, as well as
Synagoga, belong to the Ascothoracida.

The author discusses the views as to the relationship of the various
groups of the Entomostraca, and presents his own in the tabular form as
given on preceding page.

Vermes.
a Annelida.

Formation of Stolons in Syllidians.*—M. G. Pruvot discusses sepa-
rately the formation of stolons in Syllidee and Autolytide. In all cases
the stolons are produced by fission, which carries off a certain number of -
indifferent preformed segments. ‘The first phenomenon is the accentua-
tion of the groove which separates two consecutive segments ; this causes
the upper and lower trunks to become morphologically distinct from
one another; the first then regenerates its caudal extremity, and the
second reforms its cephalic extremity by a process which is exactly com-
parable to that which happens when a real section is made between them.

Natural History of Annelids.;—M. L. Vaillant has published what
may be regarded as a continuation of the well-known work of Quatre-
fages. In the first part, which alone is yet published, he deals with
the Lumbricide, Lumbriculide, and Enchytreidz on the methods of
Quatrefages’ work. Considering the large numbers of species described
during the last three years, it seems a pity the work is not up to date.

Phymosoma varians.{—Mr. A. EH. Shipley has investigated the
anatomy of this West Indian Gephyrean. The head has a crown of
tentacles, of which there are usually eighteen, arranged in a horse-shoe-
shaped lophophore, which is dorsal to the mouth. The mouth is
crescentiform. The cavity which represents the pre-oral lobe has a
peculiarly pigmented, curiously wrinkled epithelium ; this 1s continuous
with the brain, and from it two sensory pits descend into that organ.
At the posterior end of the introvert immediately behind the head a thin
-but very extensible collar is attached; the anterior end of this collar is
free, and when the introvert is inverted, it completely covers the head.
The ectoderm, except in the most anterior region, is one cell thick; it
is curiously vaulted and leaves irregularly scattered spaces between it
and the outside of the circular muscles, in which a nutritive fluid pro-
bably circulates.

* Comptes Rendus, cviii. (1889) pp. 1310-3.
+ ‘Histoire naturelle des Annulés marins et d’eau douce,’ ili., lere partie, Syo,
Paris, 1889, 340 pp. t Proc. Roy. Soc. Lond., xlvi. (1889) pp. 122-6.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 643

There is nothing peculiar in the general anatomy of this Gephyrean,
as seen by the naked eye. The author gives the name of skeletal tissue
to a peculiar form found in the collar and tentacular crown. The cells
composing this tissue are roundish, with large nuclei, and their proto-
plasm is traversed by numerous fine lines. It seems to support and
strengthen the structures in which it is found, and from its position
serves as a firm hold for the insertion of the retractor muscles of the
introvert which are attached just behind it. The cavity of the ali-
mentary canal is diminished by numerous ridges. ‘There are two kinds
of blood-corpuscles, the larger of which are found in the body and are
oval in outline, with a spherical nucleus. The smaller are found in a
closed series of spaces, usually termed the vascular system. This space
may be described as consisting of three parts all communicating with
one another, and the whole is lined by a flat epithelium.

Each nephridium consists of a bladder and a true secreting part ;
both are well supplied with muscular fibres, and are very contractile.
The bladder opens to the exterior by a circular mouth and to the
interior, or body-cavity, by a ciliated opening which has the shape of a
flattened funnel. The lumen of the secretory part is broken up into a
number of side chambers, and the whole is lined by a very peculiar
epithelium ; the cells of this are columnar in shape, and are crowded
with minute spherical granules; many of them have at their free end a
bubble or vesicle in which these granules accumulate. From time to time
these vesicles break off, and lie in the lumen of the secretory part of
the bladder; they are no doubt extruded from the body. The whole
process is very like the secretion of milk in a mammary gland. In both
sexes the reproductive organs form fimbriated ridges, which are attached
to the bases of the ventral retractor muscles, and are continuous across
the interspace between the two, ventral to the nerve-cord. 'The cells
forming these ridges are continuous with the peritoneal lining of the
body-wall.

The ganglion cells of the brain are mostly small and bipolar, but
on the posterior surface there are a certain number of unipolar giant
ganglion cells, at least four times as large in diameter as the smaller
cells. The ventral nerve-cord has no trace of a double origin or of
segmentally arranged ganglia. The sensory organs are represented by
sensory pits in the brain, and by ectodermal sense-organs in the
introvert.

y. Platyhelminthes.

Otoplana intermedia.*—Dr. G. du Plessis gives a short account of
this interesting new Turbellarian found near Nice; it is one of the
few known marine Triclads. It is blind, and has no trace of external or
internal eyes, or even of eye-like pigment-spots. There is, however, a
frontal otocyst of just the same structure as that of all the Monotide.
Right and left of it there are two dorsal ciliated fossets similar to those
of Nemertines and of the Cylindrostomata, which are very near Monotus.
The periphery of the body is provided at equal intervals and on either
side by tactile sete arranged symmetrically in pairs. On the frontal
edge they are very robust at the base, and have the form of strong
spines. The brain, which is discoidal, and the nerves which are given otf
from it are similar to those of the Monotide. The skin also resembles

* Zool. Anzeig., xii. (188) pp. 839-42,

644 SUMMARY OF CURRENT RESEARCHES RELATING TO

that of the Monotidee in that it contains among the ordinary ciliated
cells others which are agglutinating ; in these the cilia are replaced by
rough bodies which look like microscopic brushes; by the aid of these
the delicate worms attach themselves firmly to the smoothest bodies.
The reproductive apparatus is also similar to that of the Monotide, and
the creature is monogonoporous. The digestive apparatus, on the other
hand, is elegantly branched, and even in its slightest details resembles
that of other Triclades.

It is necessary to form a new genus for this Planarian, on account
of the presence of an auditory vesicle, of tactile sete, and of ciliated
pits, which are characteristics of the Rhabdoccela.

6. Incertze Sedis,

New Species of Phoronis.*—M. LL. Roule describes a new species
of Phoronis found at Cette. The individuals live in cylindrical tubes,
with resisting walls, formed by a delicate chitinous layer strengthened
by numerous small débris of sand. The tube varies from six to ten em.
in length and is from one and a half to two mm. wide; the animal is
three to four cm. long and one or one and a half mm. wide; it has from
forty to fifty tentacles. In all these points the new species is very
different from P. hippocrepis. 'The presence of two species of Phoronis
in the Mediterranean explains the presence of two types of Actinotrocha ;
for the new Phoronis the specific name of Sabatiert is proposed ;
individuals are to be found on the free valves of Tapes.

New Marine Larva.{—Mr. J. W. Fewkes describes a remarkable
larva found in the Bay of Fundy and allied to Mitraria. The body
is hat-shaped with a narrow rim, gelatinous and transparent; there are
two ciliated regions, one at the apex and the other on the rim. A bifid
protuberance hangs down from the pole of the larva opposite the apical
tuft of cilia, and from it arise two fan-shaped bundles of provisional
sete; these can be drawn together or separated. Under the apex
there is a thickening of the epiblast which is connected with the
marginal belt by means of a fine thread. There is a long tubular ceso-
phagus, the inner wall of which is richly ciliated, and which opens into
a simple elongated stomach without cilia. The larva, when expanded,
is from °15 to ‘2 mm. in diameter.

This curious form has Chetopod, Brachiopod, and Bryozoan features,
and may be supposed to resemble the archetype or ancestral form of
these three groups. It is suggested that the term Mitraria should have
its significance enlarged and be the name for the common ancestor of
these three groups. Its characteristic features are (1) an apical tuft of
cilia mounted upon an epiblastic thickening ; (2) a mouth surrounded
by a ciliated rim; and (8) a protuberance near the mouth from which
arise embryonic setz.

Echinodermata.

Ludwig’s Echinodermata.t—Prof. H. Ludwig has published the
fourth part of this work. He continues his account of the calcareous
ring, and doubts whether it is ever altogether absent ; and then describes

* Comptes Rendus, cix. (1889) pp. 195-6.
+ Ann. and Mag. Nat. Hist., iv. (1889) pp, 177-81.
+ Bronn’s Klassen u. Ordnungen, ii. 3, Echinodermata (1889) pp. 81-128.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 645

the retractor muscles. In the description of the water-vascular system the
tentacles are first considered; when these are of different sizes the
smaller are always radial and the larger interradial in position. Prof.
Ludwig is of opinion that a tentacle is homologous with a pedicel, but
that it is, as a rule, distinguished from it and advanced to a higher grade
of development by the possession of branches or terminal lobules which
are only exceptionally found on the pedicels. The great variations
exhibited by the pedicle are described and with them the ambulacral
papille are discussed. The circular canal and Polian vesicles are next
described ; the latter vary considerably in number, for while many have
only one, Holothuria oaurropa may have from eight to twelve, Chiridota
rigida fourteen to sixteen, and some of the Synapte have fifty and more.
The radial canals are next described and their topographical relations
made clear by a diagram of a transverse section through the body of a
Holothurian. After describing the tentacular canals and ampulla, and
the canals and ampulle of the pedicels, the author commences the
description of the stone-canal.

Formation of Mesoderm in Echinoderms.*—Dr. E. Korschelt has a
memoir, based on observations on Strongylocentrotus lividus, with regard
to this vexed question. The formation of the layer is a problem of some
difficulty as in all Echinoderms it arises in two ways. It commences
with a more rapid growth of the cells at the vegetative pole than else-
where; the consequence of this is that at this point the arrangement of
the cells becomes irregular; some are very soon pushed into the blasto-
col. In the course of development there are no signs of any primitive
mesenchym-cells. ‘The mesenchym owes its origin to a large number
of cells placed at the vegetative pole. The separation of the wandering
cells follows no definite law, and in the blastoccel they lie quite
irregularly by one another, so that there are not two mesenchym
stripes.

The formation. of the mesenchym is very similar in the various
groups of Echinoderms, although not in the sense of Selenka—that is,
in the presence of primitive mesenchym-cells in all Echinoderms. In
the Echinida the mesenchym arises by multiplication of the cells at the
vegetative pole of the blastula ; a similar mode is seen in Ophiurids and
in some Holothurians (Cucumaria) ; in other Holothurians the mesenchym
does not arise till a later stage in development—not, that is, till gastru-
lation begins (Holothuria) or is nearly completed (Synapta), In the last
case the mesenchym takes its origin at the tip of the archenteron, as is
the case also in Asterids and Crinoids.

It is possible that we ought to regard as the more primitive form of
mesenchym-formation in the Echinoderm that in which the wandering
cells break off from the archenteron, rather than their direct origination
from the blastoderm, which may have been more lately acquired. In
speculations of this kind, however, we must not fail to remember how
little we know as to the phylogeny of the Echinodermata.

Asteroidea of the Voyage of the ‘Challenger. +—Mr. W. Percy
Sladen’s bulky memoir deals not only with the Starfishes collected by
H.MLS. ‘Challenger,’ but also those obtained in the expeditions of the

* Zool. Jahrb., iii. (1889) pp. 653-76 (1 pl.).
+ Reports of the voyage of H.M.S. ‘Challenger’ (Zoology), xxx. part li. (1889)
pp. xlii. and 893, and atlas of 117 pls. and 1 map.

646 SUMMARY OF CURRENT RESEARCHES RELATING TO

‘Lightning,’ ‘ Porcupine,’ ‘ Knight Errant,’ and‘ Triton.’ In all, 42 new
genera and 196 new species are described. The collection made by the
‘Challenger’ is stated to afford a fair representation of the general
character of the Asterid fauna of the globe, so far as known. A large
number of abyssal forms have been found and their discovery may be
said to have opened a new chapter in the history of the Asteroidea.
The archaic characters of a number of the deep-sea forms are highly
remarkable, and furnish not only a confirmation of the validity of the
classification now adopted, but also give an important clue to the
systematic position of many members of the class.

Mr. Sladen does not take the same view of the value of the
pedicellariz as does Prof. Perrier, for he considers that the most archaic
forms have the simpler and less complex pedicellariz, nor have these organs
the more subordinate systematic value which the French naturalist also
ascribes to them. The more valuable bases for classification are to be
sought for in (1) the adaptation of the organism to subserve the fuuctions
_ of respiration and excretion, (2) the character of the ambulacral skeleton,
and (3) of the ambital skeleton. The respiratory papule may be
distributed over the whole body or confined to more limited areas, and
these may be called respectively the Adetopneusia and the Steno-
pneusia. There are two modes of growth in the ambulacral skeleton ;
the production of the parts may be accelerated in relation to the growth
of the starfish, or be retarded, or proceed pari passi ; here the terms
Leptostroteria and Eurystroteria come into use.

The third chief morphological point is the character of the marginal
plates ; these may develope rapidly, and form an important characteristic
throughout life, as in the Phanerozonia, or they may be hidden and
insignificant as in the Cryptozonia.

The three divisions to which these three sets of two names apply are
essentially equivalent, and the groups are regarded by the author as
natural orders in the strictest sense of the term. We have then the
Phanerozonia (Stenopneusia ; Eurystroteria) as the first order of the
sub-class Euasteroidea of the class Asteridea; the families included
therein are the Archasteride, of which the Pararchasterine, Pluto-
nasterines, and Pseudarchasterine are new; the Porcellanasterida,
described in 1883 from ‘ Challenger’ specimens; the Astropectinide ;
the Pentagonasteride; the Antheneide; the Pentacerotide; the
Gymnasteride ; and the Asterinide.

The second order or Cryptozonia (Adetopneusia; Leptostroteria)
contain the Linckiide, the new family Zoroasteride, the Stichasteride,
the Solasteride, the Pterasteride, Echinasteride, Heliasteride, Pedi-
cellasteride, Asteriide, and Brisingide. A synopsis of the orders and
families is given.

After describing the collection with great detail, Mr. Sladen gives a
list of stations at which Asteroids were collected, enumerating the
species found at each; then follow tables showing the known bathy-
metrical range of the genera; others which show the nature of the sea-
bottom; and finally, there is a list of the known species of recent
Euasteroidea with the principal localities, the general geographical and
bathymetrical distribution, and the synonyms. The collection of Star-
fishes seems to be one of the most important of those made by the
‘ Challenger.’

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 647

Ccelenterata.

Revision of British Actinie.*—Prof. A. C. Haddon has published
the first part of a revision of British Actinians; in this he deals with
the Sagartide, the Edwardsiide, the Haleampide, and the Zoanthez.
The general conclusions to which his work has led him may be thus
summed up. In larval Actiniz two mesenteries arise at right angles to
the long axis of the cesophagus, and divide the archenteron into two
chambers. A pair of mesenteries appear in the larger of the two
primitive chambers ; a third pair is developed in the smaller of the two
primitive chambers, and immediately afterwards another pair of mesen-
teries appear. A short resting stage now occurs, in which eight
mesvnteries are alone present, and the corresponding chambers are
produced into eight tentacles. This appears to be a characteristic
phase in the development of all the Actinie hitherto studied, with the
exception of Cerianthus. 'There is reason for believing that in most, if
not all. these eight mesenteries are homologous w:th those of the
Edwardsiz ; in other words, such forms as Haleampa, Actinia, Cereus,
and Bunodes, if not all other sea-anemones (except Cerianthus) pass
through a larval stage which is permanently retained in the adult
Edwardsie. .

The next stage is characterized by the practically simultaneous
development of two pairs of mesenteries; these for some time remain
imperfect. The fifth and sixth pairs next reach the cesophagus, and
constitute the grouud or fundamental form of the typical hexamerous
Actinie. Halcampus clavus of R. Hertwig does not advance further.

Stages of Develop-

Pie in Terie GF Table of lines of Development of certain

mesenteries. a
12 + 12, 24, &e. Typical hexameral Actiniz
|
12 + 12 Peachia Haleumps sas
|
12 Hal\campa (young)

pasate

|
Gonactinia (young) (young)-|-Zoan-
| | |

these

| |
Soe (young) (young)
| |

| | |
Scyphostoma (young) (young) (young)
larva

|

seal | |
(young) (young) (young) (young)-|-Ceri-
anthes

A pair of small mesenteries, with their longitudinal muscles facing
one another, is developed in each exoccele ; this is almost the permanent

* Sci, Trans. R. Dublin Soc., iv. (1889) pp. 297-361 (7 pls.).

648 SUMMARY OF CURRENT RESEARCHES RELATING TO

condition of Halcampa chrysanthellum and H. arenarea. These mesen-
teries grow larger, and other pairs appear successively in every exoccele
until a considerable number is developed.

The relationship of the Hydra-tuba and Scyphostoma stages of the
Scyphomeduse (Acalephz) to the Zoantharia is now generally admitted ;
a permanent octoradiate condition occurs in Hdwardsia, but it is difficult
to see where the Octocoralla (Alcyonaria) fitin. The time for a classifica-
tion or phylogeny of the Actiniz as a whole, has not yet arrived, but the
table (see preceding page) shows the line of development of some of them.

Above the black line new mesenteries arise in pairs within each
exoceele, and radially; below it the mesenteries appear in pairs
bilaterally with respect to the long axis of the cesophagus.

Actinology of the Bermudas.*—Dr. J. P. McMurrich gives an
account of the Actinians collected by Prof. Heilprin in the Bermudas.
Aiptasia cannot be separated from the Sagartide, and as it has gonads
on the first order of septa, the definition of the family given by
R. Hertwig must be amended so far as the statement that the principal
septa only are perfect and at the same time sterile is concerned.
Condylactis passiflora has grass-green tentacles, owing no doubt to the
enormous number of zooxanthelle contained in the endoderm. The
author not only considerably amends Andres’ definition of the family
Phyllactide, but removes it from the Stichodactyline to the Actiniz. A
new genus—Diplactis—is formed for two new species in which the fronds
have a tentacular appearance, so that it seems as if there were two series
of tentacles, an inner and an outer. Mammilifera tuberculata is peculiar
for the presence of zooxanthelle in its ectoderm ; as a rule these bodies
are found only in the endoderm in adult Actiniz. It is possible that
their presence is due to the thick cuticle and subcuticula preventing a
rapid aeration of the ectoderm cells, and so, by favouring the accumula-
tion to a certain extent of carbonic acid, producing favourable conditions
for the growth of the parasitic alge.

Angelopsis.t —Mr. J. W. Fewkes discusses the relationship of
Angelopsis to certain Siphonophora taken by the ‘Challenger,’ and
makes some severe remarks on Prof. Haeckel’s report on those animals.
He points out that he was the first to give an account of an Auronectid,
“the revelation of which group Haeckel styles ‘one of the most
splendid discoveries of the ‘ Challenger.’’” —

Porifera.

Structure of Flagellated Chambers in Sponges.{—Dr. R. v. Len-
denfeld points out that in all existing descriptions and figures of the
flagellated chambers of sponges, with the exception of those lately pub-
lished by Sollas and by Dendy, it is explicitly or implicitly stated that
the flagellated chambers are spaces in the sponge, on the surface of
which the collared cells stand. This, however, is not so, for the space
between the collared cells is filled by a transparent substance which is
very similar to the ordinary ground-substance of the intermediate layer
of sponges. In other words, the collared cells do not stand freely on
the surface of the intermediate layer, but are sunk into it. As a rule, no

* Proc. Acad, Nat. Sci. Philad., 1889, pp. 102-26 (2 pls.).

+ Ann. and Mag. Nat. Hist., iv. 1889) pp. 146-55 (8 figs.).
{ Zool. Anzeig., xii. (1889) pp. 361-2.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 649

boundary-line can be made out between this substance and the subjacent
ground-substance. The membranes described by Sollas and Dendy
appear to be nothing more than the boundaries—sometimes particularly
distinct—of the substance which lies between the collared cells.

Korotnewia desiderata and the Phylogeny of Horny Sponges.*—
Dr. N. Poléjaeff finds in a peculiar horny sponge called Korotnewia
desiderata that the substance of its fibres corresponds only to that of
the medulla of the heterogeneous horny fibres; the elements that form
the fibres are all polyhedral. The author believes that this discovery
confirms his view that the polyhedral cells form the medulla of the
fibres and the cup-shaped cells their margin, and that every horny fibre
has from the first its definite thickness. As the polyhedral are less
specialized than the goblet-shaped elements, it follows that the skeleton
of the ancestral form of the horny sponges is not to be sought for in the
Spongeliide, but rather among the Darwinellide. The fact that the
canal system of the Darwinellide is less differentiated than that of
the Spongeliide supports this view. As to the modern speculations
suggesting the polyphyletic origin of the Keratosa, the author remarks
that one ought not to separate artificially what one can unite naturally.

New British Sponge.t—In his account of the Porifera of the Liver-
pool Marine District, Dr. R. Hanitsch describes a new genus Seiriola,
for which he institutes a new family. This belongs to Sollas’ group
Streptastrosa, for it is an astrophorous sponge in which one of the micro-
scleres is some form of spiraster; the family is defined in the following
terms:—“The ectosome forms a cortex. Chief megascleres triznes.
The choanosomal mesoderm is cystenchymatous. S. compacta sp. n. was
found at Puffin Island, where it forms a knob-like mass. In this report
seven species are added to the list of forms recorded from that neigh-
bourhood, one of which—Reniera semitu! ulosa—is new to British seas.

Protozoa.

Chlorophyll in Animals.t—M. P. A. Dangeard, who remarks that
chlorophyll-corpuscles have never yet been observed in the Flagellata,
reports its presence in Anisonema viridis [e¢] sp. n., which contains a
large number of green granules, placed in the ectoderm. The author,
who believes that these green bodies are parasitic Alg, notes that their
presence is connected with the existence of a gelatinous secretion, in the
interior of which the individuals are reproduced by division. A similar
gelatinous investment is found in Ophrydium versatile, where the cysts
resemble a large Pleurococcus ; the protoplasm seems to be coloured
uniformly green, the membrane is thick and striated by bands which
intercross like those of the cysts of Stylonychia mytilus. We do not yet
know how the green corpuscles behave when the host is encysted ; if they
lose their individuality the author recognizes that it will be necessary to
abandon the idea of their being parasitic. It is possible, however, to be
certain by means of reagents that the green corpuscles remain distinct.

Biitschli’s Protozoa.§—Prof. O. Biitschli continues his systematic
description of the Ciliata. The second suborder, or Spirotricha, is

* Zool. Anzeig. (1889) pp. 366-7.

+ Liverpool Biol. Soc., iii. (1889) pp. 155-73 (8 pls.).

} Comptes Rendus, eviii. (1889) pp. 1313-4.

§ Bronn’s Klassen u. Ordnungen, 1., Protozoa (1889) pp. 1713-1840.
1889. . 2h

650 SUMMARY OF CURRENT RESEARCHES RELATING TO

divided into four sections: the Heterotricha, among which Balaniti-
diopsis is a new genus for Balantidiwm duodeni Stein, the Oligotricha,
the Hypotricha, the Peritricha. The author's views as to the phylogeny
of the subclass Ciliata are shown in the accompanying table :—

y Opalinina
PERITR. HYPOTR.OLIGOTR. Stentorina G 2;
* Bursar. Plagiotomina e
foe Isotri¢hina
0 rR, ae
“ Microthorac. of! ne
/ On ¢;;, Paramaecidina
/ Pleuronem) Se idin
SPIROTRICHA | re Urocentrina
y é
2 PS ;
i
Y,
; g PARAMAECINA (Aspirotricha )
/ HOLOTRICHA
ra Chlamyd.
G Trachelina
/ Colepina

Holophryina
/

v
7 . ry
7 Cyclodinina

The author next proceeds to discuss certain physiological-biological
points, commencing with the phenomena of regeneration ; those of move-
ment are next considered, and then the processes of digestion. ‘The
interesting chapter on modes of life contains a list of parasitic forms
arranged under the heads of their respective hosts, from which Birds
and Reptiles are absent. The influences of temperature, of chemical
substances and of electricity are described. The part before us con-
cludes with an account of the parasites of the Ciliata.

Parasitic Trichodina.*—Herr J. Carriére describes a species of
Trichodina (? pediculus) which is found living in the lateral canal or
wall as on other parts of the body of Cottus gobio and eating blood and
lymph-corpuscles. In bony fishes there appears to be normally a
constant and often very well marked migration of lymph-cells into the

* Arch. f. Mikr. Anat., xxxiii. (1889) pp. 402-15 (1 pl).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 651

epidermis. These are best and most numerously seen in the lowest layers
of the stratum Malpighii; thence they can be traced through the whole
of the epidermis as far as the uppermost layers.

Parasitic Protozoa in Hooping Cough.*—Some time since Dr. C.
Deichler asserted that parasitic Protozoa were to be found in the
matter coughed up in hooping-cough, and that they had some etiological
connection with the affection. As this conclusiou was not accepted, he
has made some further observations. There appears to be a cycle of
forms belonging to a ciliate animal. Those which are regarded as
embryos are circular in form and have a double contour; the circle
varies in size, but is ordinarily as large as the larger epithelial round
cells found in the sputum. In the vacuolar space inclosed by the ring
there is a clear vesicle or a corpuscle provided with highly refractive
eranules of the size of a lymphoid cell. This vesicular or granular
body carrics a circlet of fine, clear cilia which move actively. The
ciliated and actively moving embryos come to rest after a time and
undergo further development. In the more developed bodies the
contents break up into a granular protoplasm, and the nucleus has a
double contour. The embryo gives rise to a distinctly characterized
unicellular organisin. The amceboid cells of this stage vary both in
form and size, aud are provided with hairs. The author has also
observed encystation ; the encysted forms often break up into a number
of more or less large, rounded or oval fragments, and this breaking-up
appears to be due to cold or to the drying up of the mucus. From these
fragments cells are again produced, which vary in size with the fragment
from which they take their origin.

Of similar parasites observed in Man the author remembers only
Balantidium coli, which, though more highly organized, exhibits many
analogies with the parasite here described.

Micro-Organisms in Paunch of Ruminants.;—M. A. Certes calls
attention to the presence of glycogen in the Infusoria found in the
paunch of Ruminants, and especially of Roedeer. In Entodinium there
is a certain localization of this material, while iu Isotricha it appears to
be uniformly distributed through the organism. In the Roebuck there
was found a single species of Ophryoscolex which is very small and has
no caudal appendage; the species is very abundant, and has associated
with it a cruciform Flagellate, some of the examples of which have two
flagella instead of one; the author proposes to call this form Ancyromonas
ruminantium. Microbes characterized by their physiological properties
rather than by their form are found in abundance in the paunch of
Ruminants, and it is very probable that they play an important part in
digestion.

Intimate Structure of the Plasmodium Malarie.{—Prof. Celli and
Dr. Guarnieri have by the methylen-blue method made observations on
the intimate structure of the plasmodium, both in the amceboid and cres-
cent-shaped conditions.

They find that in all plasmodial forms two substances can be distin-
guished : the first peripheral, a kind of ectoplasm, is more refractive and

* Zeitschr. f. Wiss. Zool., xlviii. (1889) pp. 303-9 (1 pl.).
+ Journ. de Micrograpliie, xiii. (1889) pp. 277-9.
+ Riforma Medica, 1888, Nos. 208 and 236. See Centralbl. f. Bakteriol., v.
(1889) pp. 91-3.
PAY eee

652 SUMMARY OF CURRENT RESEARCHES RELATING TO

more deeply stained by methylen-blue; the second, an internal substance
or entoplasm, more centrally disposed, is less refractive and less deeply
stained.

In the endoplasm of the pigmented amoeboid forms is distinguishable
both in the unstained and stained conditions a nucleus, within which are
1-8 more deeply stained nucleoli. Without the nucleus is a vacuole.

The authors have, further, observed that in one and the same mala-
rious patient the process of reproduction is effected in three different
ways:—(1) The division of the protoplasmic substance is complete,
many different corpuscles being formed, while of the mother plasmodium
only the pigment-corpuscles remain. (2) The division of the proto-
plasm is incomplete, one part of it remaining together with the pigment-
granules as an irregular granular mass. (3) The pigment becomes
arranged in small circles surrounded by protoplasm. From this
originate small pigmented bodies, some of which are in connection with
the parent, while others present a pigmented flagelliform prolongation.

The transition from the crescent shape to the oval, from this to the
round, with the pigment heaped up in the centre, and finally to the
flagelliform condition, can be observed on the hot stage of the Microscope.

Assuming that all these forms belong to one and the same species,
the Plasmodium malariz would have two chief phases of endocellular
development in the blood, viz. those peculiar to the amceboid and those
peculiar to the crescent-shaped varieties, under the latter term being
included the spindle, oval, flagellate, and round forms.

The authors consider, from its morphological characters, that the
Plasmodium malariz should be classed with the Sporozoa, and, to express
their position more accurately, placed under the class Gregarinidz, Order
Coccidiide.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 653

BOTANY.

A. GENERAL, including the Anatomy and Physiology
of the Phanerogamia.

a, Anatomy.* —
(1) Cell-structure and Protoplasm.

Formation and Growth of the Cell-wall.;—Herr E. Zacharias has
investigated this subject in the case of the rhizoids of Chara fetida.
The membrane of the apex of the hair becomes considerably thickened
when the nodes on which the rhizoids grow are removed from the plant
and cultivated, the thickening becoming very considerable in the course
of a.few hours. The first indication of this thickening is a layer of
minute granules which is deposited on the membrane of the apex of the
rhizoid ; the exact manner in which these granules are formed out of
the protoplasm is not clear; but in the course of a few minutes they
have formed themselves into a layer of extremely delicate rods, placed
vertically to the membrane, which gradually become longer and thicker,
and finally unite into a continuous layer of cell-wall. The chemical
reactions of the original granules could not be determined ; but the rods
very soon show a distinct cellulose reaction with chlor-zinc-iodide.

It must be concluded from the above that, in this case at all events,
the cell-wall increases in thickness by the deposition of a new formation
which is excreted from the protoplasm in the form of a layer of minute
granules, from which is developed a layer of rods manifesting the
reaction of cellulose. We have not here.any direct transformation of a
peripheral layer of protoplasm into cellulose; there is a much closer
resemblance to the new formation of a cell-wall in cell-division. The
young dividing-wall between two sister-cells of the rhizoids of Chara
consists in the same way of minute rods placed vertically to the growing
wall, which subsequently unite into a continuous layer.

After its first formation the thickening-layer of Chara continues to
increase considerably in thickness; but there is no further trace of any
new-formation, nor of an inner lamella differing in structure or reactions
from the rest of the thickening-layer. There is certainly here no
constant apposition of fresh layers of cellulose on the inner surface of
those previously in existence; and in some rhizoids even the formation
of the primary layer, as above described, could not be detected. The
growth in thickness of the cell-wall therefore takes place either by intus-
susception or by the successive deposition of minute particles of cellulose
on the cell-wall. Whether the superficial growth takes place by intus-
susception or by simple stretching could not be determined; but the
facts seem rather to favour the first of these theories.

(2) Other Cell-contents (including Secretions).
Pure Chlorophyll.{—Herr A. Hansen gives a summary of tke ex-
isting chlorophyll-literature, now agrees with the view of Tsschirch

* This subdivision contains (1) Cell-structure and Protoplasm; (2) Other Cell-
conteuts (including Secretions); (8) Structure of Tissues; and (4) Structure of
Organs.

¢ Jahrb. f. Wiss. Bot. (Pringsheim), xx. (1889) pp. 107-32 (3 pls.); and Ber.
Deutsch. Bot. Gesell., vi. (1888) Gen.-Vers.-Heft, pp. lxiii—v.

t ‘Die Farbstoffe des Chiorophylls” 88 pp. and 2 pls., Darmstadt, 1889. See
Bot. Centralbl., xxxvili. (1889) p. 632.

654 SUMMARY OF CURRENT RESEARCHES RELATING TO

that the substance previously described by him as chlorophyll-green is
in reality a compound of that substance with sodium. He has now
succeeded in separating pure chlorophyll-green by the following process.

Grass-leaves are boiled in water from a quarter to half an hour, then
washed in water, pressed, and dried in the dark. The chlorophyll-
pigment is then extracted with boiling alcohol, and the solution saponified
by heating for three hours with a slight excess of caustic sodium. The
excess of sodium is converted into carbonate by carbonic acid, and the
mixture thus obtained dried in a water-bath. The chlorophyll-yellow
is then extracted by ether, in which the compound of chlorophyll-green
with sodium is quite insoluble, and afterwards by a mixture of equal
parts of alcohol and ether, in which it is only slightly soluble, and the
residue again by a mixture of equal parts of alcohol and ether and
phosphoric acid. This sets free the chlorophyll, which dissolves in the
mixture of alcohol and ether, and can be evaporated as a shining black-
green perfectly solid brittle substance, insoluble in water, benzol, and
bisulphide of carbon, soluble with difficulty in pure ether, easily in
alcohol. The solution has a beautiful pure green colour, which becomes
red and strongly fluorescent when concentrated. It offers great resis-
tance to reagents, especially mineral acids. Its exact composition has
not been ascertained, but it contains iron and nitrogen.

The author then describes the process for obtaining pure chlorophyll-
yellow, which crystallizes in orange-red crystals, ins» luble in water, but
soluble in alcohol, ether, chloroform, and benzol with a dark yellow, in
bisulphide of carbon with a red colour. The yellow chlorophyll of
flowers and fruits, and that contained in the petals of the poppy, is
identical with the chlorophyll-yellow of leaves.

The optical properties of the various chlorophyll-pigments are then
described ; and finally, the mode in which these pisments are contained
in living chloroplasts. The author states that the green substance which
fills up the vacuoles of the chlorophyll-grains is not a solution, but
consists of combinations of the two chlorophyll-pigments with fatty
acids, which possess a half-solid consistence; and the same is true of
the chromop!asts.

Physiology of Tannin.*—Herr G. Kraus gives a resumé of the most
trustworthy investigations that have yet been made of the nature and
function of tannin; the mode of investigation beimg Lcewenthal-
Schroeder’s, viz. trituration with chameleon, and extraction with water
until the water becomes perfectly colourless.

Tannin is produced in the leaves under the influence of light ; its
decrease when the light is removed, is due, not to its decomposition, but
to its transference to the stem and branches, and a fresh formation of

‘secondary tannin, as it is termed by the author, takes place in the newly-
formed organs, even in the dark. The conditions for the production of
tannin are, in general, the same as those for carbonic assimilation, and
the formation of this secondary tannin is closely analogous to the similar
phenomenon in the case of starch.

The author regards tannin, from a physiological point of view, simply
as an excrementitious product, and also, in some cases, as serving to
protect the plant from being devoured by animals, or from decay.

* ¢Grundlinien zu einer Physiologie d. Gerbstoffs,’ 8vo, Leipzig, 1889, 131 pp.
See Bot. Centralbl., xxxviil. (1889) p. 447.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 655

Herr M. Westermaier,* commenting on Kraus’s conclusions, points
out that, according to his own observations, tannin does in some cases
serve as a reserve-material for the building-up of new tissues, as in that
of the formation of roots on the branches of Salix.

Formation of Calcium oxalate in plants.;—Herr F. G. Kohl con-
tends that lime can enter into soluble combinations with the carbo-
hydrates in the tissues of plants, and that it is in the form of these
compounds that the transference of lime takes place from one part of the
plant to another. He has obtained a compound of this kind of grape-
sugar and lime in both the solid and the dissolved condition. The
organs, therefore, where starch and other carbohydrates are stored up—
rhizomes, tubers, bulbs, seeds, bast-fibres, &c.—are also those where the
separation of calcium oxalate takes place. Moreover, all organs where
albuminoids are being formed have a decided acid reaction from the
presence of oxalic acid. This is readily proved in the case of growing
points. If light is excluded, calcium oxalate is formed only in small
quantities, or not at all.

Influence of Light on the formation of Calcium oxalate.t—Herr
N. A. Monteverde has demonstrated, by experiments on Papilionacez,
that the intensity of light has a very powerful influence on the amount
of crystals of calcium oxalate formed in the stem and leaves,

~

Production of Honey in Convallaria.s—Herr S. Almquist describes
the mode of production of the honey in the flowers «f Convallaria
Polygonatum and multiflora, viz. not from any pit at the base of the
perianth-tube, but from the primary veins of the perianth, especially of
the sepals. This may probably be the original type from which are
derived all the various modes* of secretion found in the Liliiflore, viz.
from the central nerve of the petals (Lilium, Fritillaria, Gagea, &c.),
from folds between the carpels (Allium, Ornithogalum, Hyacinthus), and
from the tissue of the spur (some Orchidez).

(3) Structure of Tissues.

Foliar Vascular Bundles. ||—-M. A. Prunet has made a close exami-
nation of the changes which the vascular bundles undergo in passing
from the stem to the leaves, chiefly in Dicotyledons. The vessels
diminish in size, usually becoming more numerous, and have thinner
walls; the large secondary vessels disappear, while the primary vessels
increase in number. ‘I'he supporting elements of the bundle — the fibres
and the lignified parenchyme—disappear, and, when the bundle has
reached the base of the leaf, the vessels, usually arranged in rows p'aced
in a fan-like manner, are accompanied by parenchyme formed of cells
which are usually elongated, and have very thin walls. As a rule the
largest vessels are near the base of the bundles, thence diminishing
gradually towards the periphery, rapidly towards the base. The inter-
calary parenchyme betweeu the bundles is remarkable from its richness

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 98-102.
+ Bot. Centralbl., xxxviii. (1889) pp. 471-5. Cf. this Journal, 1888, p. 445.
{ Arb. St. Petersburg. Naturf. Gesell., xviii. pp. 4€-7. See Bot. Centralbl.,
XXXvili. (1889) p. 486.
§ Bot. Sallsk. Stockholm, March 21, 1888. See Bot. Centralbl., xxxviii. (1889)
. 663.
: || Comptes Rendus, evili. (1889) pp. 867-9.

656 SUMMARY OF CURRENT RESEARCHES RELATING TO

in chlorophyll and starch, often accompanied by crystals of calcium
oxalate.

From the period of their entry into the leaf the foliar bundles
present a return to their primary structure ; the vessels increase in size
and diminish in number, with increase in the thickness of their walls;
the large secondary vessels and the sclerenchyme sometimes reappear ;
the latter from reasons purely mechanical. In pinnatinerved leaves the
largest vessels are often found in the midrib at a certain distance from
the base of the lamina; the vessels in the middle, and even towards the
apex of the lamina, are frequently larger than those towards the base of
the leaf.

All these modifications appear to be in accord with the conducting
function of the bundles; the large vessels in the petiole and principal
veins may be connected with the turgidity of the leaf.

Anatomy of Floral Axes.*—M. Labarie has studied the differences
between the anatomical structure of ordinary stems and of the floral ©
axes in the same plant, which he finds, with great uniformity, as follows:
—In the pedicels the cortex is more developed, the vessels of the wood
more numerous and smaller, and the pith more developed than in the
vegetative axes; and this applies not only to pedicels properly so called,
but also to the fruit-bearing axes, i.e. to those special small branches on
which alone in certain trees, such as apples and pears, the floial pedicels
are developed.

Development of the Vascular bundles of Monocotyledons.j—
Fraul. $8. Andersson finds that the development of the vascular bundles
in Monocotyledons does not differ so widely from that in Dicotyledons
as has generally been stated; and that there is, in fact, a close
resemblance in this respect between Liliaceew and Ranunculacee. In
most of the larger groups of Monocotyledons there are genera in which
there is a distinct development of a cambium-zone at an early period,
which subsequently more or less completely disappears. This is
illustrated by examples from the various families. In Liliwm there is a
distinct intermediate tissue between the xylem and phloem, composed of
a meristem which divides by tangential walls, and contributes to the
growth of the young bundle. This is also strongly developed in some
other genera belonging to the Liliacee and to allied orders, while in
others it is almost completely suppressed. In the Graminezx there may
be detected, even in old vascular bundles of Zea Mays, remains of a
cambium-zone composed of cells arranged radially between the xylem
and phloem, The same is the case with some palms. In aquatic
genera, such as those of Alismacerw, Naiadacew, and Typhaceex, the
vascular bundles are much more feebly developed.

Secretion-receptacles in the Cactaceew.{—Dr. C. Lauterbach has
examined the structure and mode of formation of the mucilage and gum-
cells, crystal-cells, and laticiferous ceils, in a large number of species
belonging to this order, preceding hig description by a general account

* Rech. s. ’anatonie d. axes floraux, Toulouse, 1888. See Bonnier’s Rev. Gén.
de Bot., i. (1889) p. 91.

+t Bih. K. Svensk. Vet. Akad. Handl., xiii. (1888) Afd. 3, No. 12. See Bot.
Centralbl., xxviii. (1889) pp. 586 and 618.

‘ Bot. Centralbl., xxxvii. (1889) pp, 257-64, 289-97, 329-36, 369-75, 409-13
(2 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 6957

of the anatomical structure of the genera Mammillaria, Echinocactus,
Echinopsis, Cereus, Phyllocactus, Epiphyllum, Rhipsalis, Opuntia, and
Peireskia. The characters derived from the presence of various kinds
of secretion-receptacles follow, as a general rule, the other characters
which distinguish the genera. The species may be divided, from this
point of view, into three categories :—those in which crystal-cells only
are present; those which possess both crystal-cells and latex-passages ;
and those which have both crystal-cells and mucilage-cells,

The mucilage-receptacles are always cells, very rarely having the
character of passages; they may contain also separate crystals of
calcium oxalate, or sphero-crystals; they are distinguished from the
adjacent parenchyme-cells by their much greater size, and are usually
found in the chlorophyll-tissue; they do not occur in the root. In
some species they are found also in the pith; in the leaves of
Opuntia they are scattered through the palisade-parenchyme. The
latex-receptacles are confined to species of Mammillaria, where they
have the form of a system of passages ; these are of lysigenous, and not,
as de Bary states, of schizogenous origin. They occur chiefly in the
cortical and palisade-parenchyme, extending also to the root. Crystal-
cells are found in all the Cactaceze without exception; they are usually
thin-walled cells containing a single cluster of crystals of calcium
oxalate. These are sometimes present in such enormous quantity that
they constitute 85 per cent. of the ash, especially in old woody stems.

The mode and place of formation of the mucilage-cells and other
receptacles is described in detail in several species and genera. As
regards their physiological function, the author regards the mucilage-
cells as serving as receptacles for moisture in dry situations and climates,
the latex-passages and crystal-cells as serving to protect from the
attacks of animals, and as increasing also the rigidity of the stem.

Transfusion-tissue of Coniferee.*—Herr G. A. Karlsson has studied
the structure of the transfusion-tissue in the leaves of a large number
of Coniferee. Pinus austriaca may be taken as a type. The cells which
surround the true vascular bundles within the bundle-sheath are of four
kinds, viz.:—(1) The true transfusion-cells which occupy the greater
part of this space: these are isodiametric, and have several circular pores
on each of their lignified walls; on the xylem-side of the bundle they
pass gradually into (2) the pith-like transfusion-tissue, the elements of
which are very long, with evident intercellular spaces, and minute pores
in the thin slightly lignifiel walls. (8) The bast-fibres, often divided
by thin septa, forming a plate below the phloem of the bundle. (4)
Among the true transfusion-cells are isodiametric elements which may
be called transfusion-cells with simple pores, bearing a resemblance to
sieve-plates. The xylem of the vascular bundle passes over into the
true transfusion-tissue by a tissue which may be called transfusion-
xylem, the phloem into the transfusion-cells with simple pores by a
transfusion-phloem. The author distinguishes also four types as respects
the position of the transfusion cells in the vascular bundle.

Increase in thickness of the arborescent Liliacee.t—Dr. P.
Réseler has made a study of the mode of thickening of the stem and

* Acta Univ. Lund., xxiv. (1887-8) No. 7, 58 pp. and 1 pl. See Bot. Centralbl.,
XxXviii. (1889) pp. 730 and 756.
+ Jahrb. f. Wiss. Bot. (Pringsheim), xx. (1889) pp. 22-348 (4 pls.).

658 SUMMARY OF CURRENT RESEARCHES RELATING TO

of the formation of the secondary vascular bundles in Yucca, Dracena,
and Aloé. The phenomena are the same in essential points in the
three genera.

The stem of any of these plants may be divided into three regions.
The central portion consists of a loose tissue in which are scattered a
comparatiyely small number of vascular bundles, becoming more
numerous towards their periphery. This portion is surrounded by a
usually annular zone, sharply differentiated and of closer and firmer
structure, in which are a much larger number of vascular bundles ; these
are usually arranged in concentric circles, giving the impression of the ©
annual rings of a dicotyledonous stem ; and they are even traversed by
radial striz resembling the medullary rays; these are in connection
with the leaf-traces in the central cylinder. The outermost zone, the
cortex, is again composed of loose tissue, and is bounded on the outside
by a more or less developed layer of cork. This annular woody zone
continues to increase in thickness below, gradually disappearing towards
the summit, so that the entire mass resembles a truncated cone, the
result of a secondary increase in thickness, and surrounded by a zone
of meristem from which are formed new parenchyme and vascular
bundles. The leaf-trace-bundles bend out from the central cylinder to
the cortex. In each bundle the phloem lies towards the centre of the
stem, and is half surrounded by the annular and spiral vessels imbedded
in parenchyme; and these are sometimes accompanied by tracheides.
In the leaf-trace-bundles the true vessels gradually disappear. The
secondary vascular bundles of the cone contain only tracheides and
parenchyme, never true vessels.

The segments of the initial cells from which the thickening-ring
originates do not appear to divide in accordance with any generai law;
nor do they form a ring, as in l)icotyledons and Gymnosperms. The
multiplication of the thickening-rings also does not take place in the
same way; and the divisions in the thickening-ring cannot be traced
back to initial cells, i.e. to cambium-mother-cells which are capable of
dividing without limit, forming alternately wood and cortex.

With regard to the development of the secondary bundles, the
author does not agree with Kny that the tracheides are the result of
the coalescence of cells; but, on the contrary, he believes that they can
originate in no other way than from the development of single celis in
the rudiments of the bundles.

Primary Cortex in Dicotyledons.*— According to Herr Tedin, a
cork-layer is usually formed during the first year in woody Dicotyledons,
either in the epiderm or in that portion of the primary cortex next the
epiderm; less often in the inner portion of this tissue, or in the
bast. When the cork-layer has an outer position, the cortical tissue or
primary cortex is usually more strongly developed, and has thicker
walls, than when it occupies a more central position; the first case
presenting a resemblance to those plants which do not form cork during
the first year. When the cork-layer has a more internal position, the
primary cortex has usually ceased to be a living tissue at the close of
the period of growth, when it splits and peels off. When the cork-
layer has a more external position, or is wholly wanting during the first

* SB. Bot. Ver. Lund, Feb. 25, 1888. See Bot. Centralbl., xxxyii. (1889)
pp. 300 and 380, and xxxviii. (1889) p. 727.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 659

year, the outer cortex usually forms a collenchymatous hypodermal layer,
which is not the case where the cork-layer is more internal, or at least not
to the same extent. In Ulmus and Tilia the inner cortex contains mucilage.

The various special modes of development of the primary cortex are
then classified under 10 different heads. In the first 6 the primary
bark consists of two and only two distinct layers. In the first 5 of these
the outer layer is distinctly collenchymatous. Of these again two types
have a homogeneous inner layer (Sorbus, Crategus, Syringa vulgaris,
Viburnum Lantana, species of Rosa, most Salicacee and Betulacez, and
others), while in 3 the inner bark is heterogeneous (Ulmus montana,
Tilia, Cupuliferee, Juglans). In the sixth type the outer cortex is not
distinctly collenchymatous ( Vaccinium vitis-idzea, Azalea procumbens, &c.).
In the seventh the primary cortex is differentiated into more than two
layers (Leycesteria). In the eighth it is differentiated into two layers
only in certain longitudinal strips (Viburnum Opulus, Cornus sanguinea,
Forsythia, &c.); while in the remaining two there is no distinct
differentiation into more than one layer (Rhamnus cathartica, Prunus
spinosa, Hippophae rhamnoides, &c.).

Pericycle.*—M. A. de Wevre states that before Van Tieghem the
pericycle was known under the name of pericambium or rhizogenous
layer. In the root the first indication of the pericycle was given by
von Mohl in 1831. Generally the pericycle is formed of a single layer
of cells (Ranunculus, Veratrum, &e.), less often of two layers (Vanilla
planifolia), or it may be of a larger number of cells (five to six in
Cynodon Dactylon). It is said to be homogeneous when all the cells are
similar, and heterogeneous when it is composed of cells of various kinds,
as in Araliacezee, Umbellifere, and Pittosporee. The heterogeneous
pericycle is most commonly met with. The author then points out
various modifications which the pericycle may undergo, and concludes
by stating that, in general terms, the root and the stem may be said to
be composed of three principal zones :—(1) The cortex, comprising all
the tissues up to the endoderm; (2) the pericycle; (3) the central
cylinder, composed of pith, wood, cambium, and liber. In the root a
portion of the secondary central cylinder is sometimes formed by the
pericycle.

Mechanical System in the Roots of Aquatic Plants.t—M. C.
Sauvageau states that M. L. Olivier in 1881 established that in Mono-
cotyledons the endoderm and peripheral membrane of the central cylinder
are capable of thickening; the thickening being a protection to the
liber-bundles.

The central cylinder of the root of Naias major is composed of one
or two axile vessels, representing the xylem, surrounded by a variable
number of sieve-tubes of pericyclic origin separated from the central
bundle by conjunctive cclls. No element of this central cylinder is ever
lignified or subevrized, all the walls remain white, and iodine and sul-
phuric acid colour all the cells blue. The radial walls of the endoderm
display elegant foldings. In the piliferous layer of the root the piliferous
cells alternate regularly with cells which do not produce hairs; the
hairs have ultimately a singular collar near their base.

The central cylinder of the root of Naias minor is somewhat simpler

* CR. Soc. Bot. Belg., 1889, pp. 41-7.
¢ Journ. de Bot, (Morot), iii. (1889) pp. 3-11, 61-72, 169-81 (19 figs.).

660 SUMMARY OF CURRENT RESEARCHES RELATING TO

than that of N. major. Here there are one or two axile vessels separated
from the endoderm by a single row of cells in which are 3-4 sieve-
tubes. The central cylinder of the root of N. minor and of N. major is
therefore but very slightly lignified, and corresponds to a single bundle
with an axile vessel representing the xylem and peripheric phloem.

The author then describes the structure of the root of several species
of Potamogeton. In P. natans not only can the endoderm thicken its
cells either on their outer or on their internal and radial faces, but
the permeable places are frequently wanting. All the elements of the
central cylinder are susceptible of thickening or lignifying, the sieve-
tubes only being an exception. Every species of Potamogeton studied
by the author possessed true vessels, and several possessed sclerenchy-
matous tissue to a greater or less extent. When the sclerenchyme was
feeble, it showed in the endodermal cells opposite the liber.

M. Sauvageau next describes the mechanical system in the roots of
Zostera, Cymodocea, and Posidonia. The anatomy of these plants differs
very considerably, Zostera and Cymodocea possessing no lignified elements
in their roots, while Posidonia Caulini, which is deeply submerged,
possesses on the contrary a ligneous conducting system and an im-
portant sclerotized mechanical system, which renders the root hard, and
gives to it a considerable power of fixation. Comparative anatomy has
shown that aerial roots when they become subterranean, or subterranean
roots when they become submerged in water, lose either in part or
altogether the property of thickening, and especially of lignifying their
cell-walls; but this conclusion is due in certain cases to a sickly
condition of the roots, which is a result of their existence in a different
medium from that for which they were adapted.

Comparative Anatomy of the Aristolochiacez.*—Dr. H. Solereder
describes the various points of anatomical structure in this order,
especially in relation to the leaves, the vascular bundles, the fruit, and
the seeds. Secretion-cells occur throughout the order, and in almost all
the species they are found in the lamina of the leaf, in the epidermal
tissue as well as in the mesophyll. They may occur in the epiderm of
both surfaces, or in that of the under surface only; their walls are very
often suberized ; their contents are in the form of yellowish or whitish
drops. When occurring in the leaf, they are to be found also in the
flower. The pollen-grains are always spherical, with neither fissures nor
pores.

Structure of Apocynacez.t—According to M. Garcin, plants
belonging to this order are characterized by the presence of a double
liber in the stem, an outer and an inner portion, and by the occurrence
of unseptated laticiferous tubes, and of a pericycle inclosing bundles of
fibres with thick walls composed of cellulose. The same essential
characteristics occur also in the Asclepiadez.

Anatomy of Dioscoreacez.{—From the examination of a number of
species belonging to this order, Herr J. R. Jungner describes the

* Engler’s Bot. Jahrb., x. (1888-9) pp. 410-524 (8 pls.). See Bot. Centralbl.,
XXXViil. (1889) p. 855.

+ Ann. Soc. Bot. Lyon, xv. See Morot’s Journ. de Bot., Rey. Bibl., iii. (1889)
p. xliii.

+ Bih. K. Svensk. Vet.-Akad. Handl., xiii. (1888) Afd. 3, No. 7. See Bot.
Centralbl., xxxviii. (1889) pp. 734 and 760.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 661

peculiarities of structure in the following points :—General differentiation
of the tissues ; epidermal tissues ; fundamental tissue ; vascular bundles,
with respect to their course, the various tissues of which they are com-
posed, and the structure of their elements. He considers that the most
important characters in the differentiation are to be derived from the
epidermal tissue. The various points of structure are described in great
detail.

Fibres and Raphides in Monstera.*— Mr. W. 8. Windle describes
the presence in the exocarp or inedible portion of the fruit of Monstera
deliciosa not only of raphides, but also of slender, sharp-pointed, needle-
like cells or fibres, apparently half-imbedded in the large-celled paren-
chymatous tissue. It is these chiefly which cause the sharp stinging
sensation in the tongue and palate when this outer coating of the fruit
is taken into the mouth.

(4) Structure of Organs.

Obdiplostemonous Flowers.;—By this term Herr K. Schumann
understands those flowers in which there are two whorls of stamens, and
the carpids are opposite the members of the outer whorl. This structure
occurs in many orders of Apopetale ; among Gamopetale only in the
Bicornes (Rubiacew, &c.) ; in Monocotyledones it is unknown. From
the numerous cases observed by the author he holds that the law of
alternation of members of adjacent whorls has been too absolutely laid
down by morphologists ; it is broken through where the members of the
preceding whorl are very small, or when they are of cap-like form.
This is also the case with regard to the law of acropetal succession in
the development of the different organs of the flower, which may be
interrupted by the interposition of members of additional whorls. He
regards contact alone as sufficient to determine the position of the
carpids in isomerous flowers, and in others also in which abortion has
taken place of members of particular whorls.

Pollen-grains.t—Prof. B. D. Halsted points out that pollen-grains
frequently alter their shape greatly when wetted. Oval grains may
increase as much as 33:2 per cent. in their shorter diameter, while
shrinking 12-2 per cent. in their longer diameter. Many grains have
characteristic folds which are lost when the grain is wetted. The pores
are not usually so evident in the dry pollen as when it iswet. For full
and perfect representation of a pollen-grain it should be measured twice ;
when dry, that is, in the condition to pass from the anther to the stigma,
and again when fully swollen by the imbibition of water. The largest
diameter measured was 130-138 yp, in Ginothera biennis.

Form of Pollen-grains.§S—According to Herr F. Tschernich, the
morphological structure of the pollen-grain is sometimes uniform
throughout entire orders, as in the Conifer, Graminew, Composite, and
Caryophyllacee. In other cases it can be used to determine the genus,
as in Salix and Populus among Salicacee, Euphorbia, Buxus, and Crotun

* Bot. Gazette, xlv. (1889) pp. 67-9 (1 pl.).

+ Jahrb. f. Wiss. Bot. (Pringsheim), xx. (1889) pp. 349-426 (1 pl.).

{ Bull. Torrey Bot. Club, xvi. (1889) pp. 135-6.

§ ‘Ueb. d. Bedeutung d. Pollens f. d. Charakteristik d. Pflanz:n,’ 1888. See
Pot. Centralbl., xxxviii. (1889) p. 833,

662 SUMMARY OF CURRENT RESEARCHES RELATING TO

among Euphorbiacee. Occasionally it is of systematic value even
within the genus, as in the various species of Pyrola.

Nectarial Scales of Ranunculus.*—Herr 8. Almquist describes an
abnormal specimen of Ranunculus aconitifolius, in which the outer
margin of the honey-gland on each petal had developed into a petal-like
structure. He draws the conclusion that the original form of the honey-
gland is that of the subgenus Batrachium, and of RK. sceleratus, viz.
an open hollow pit, from which all the other forms found im the genus
are derived.

Structure of the Bracts and Bracteoles in the Involucre of Corym-
biferze.|—M. L. Daniel describes the anatomical structure of the bracts
and bracteoles in various genera of Corymbifere. The author points to
Buphthalmum salicifolium as the most differentiated of the Corymbifere,
the bracteole possessing two bands, while in Gnaphalium, Antennaria,
Filago, &c., there is only one band.

Development of Berry-like and Fleshy Fruits.t—Herr J. Bordzi-
lowski describes the development of a large number of fruits of different
kinds. The course of the vascular bundles in the carpels is always the
same as in the leaves; i.e. there are a median and two marginal bundles ;
and if the ovary consists of several carpels, each pair of marginal bundles
may coalesce. When the ovary is superior and monocarpellary, there is
only a single ring of bundles; if it consists of more than one carpel,
there may be two rings. In inferior ovaries the bundles belonging to
the calyx-tube form an independent ring. 'The development of a fleshy
fruit from an ovary takes place in different ways; this is indicated in
the cases of the drupe, the berry of Ampelopsis and Sambucus, the apple,
and the cucumber.

Septated Vittee of Umbelliferee.s—Herr A. Meyer describes the vitte
or oil-receptacles which are almost universally found in the pericarp of
ripe fruits of Umbelliferz as being clothed with a peculiar layer, which
is itself protected by a special cuticle-like membrane which completely
covers the outer surface of the epithele, the whole forming a sac inclosing
the special secretion. In only a few species (Coriandrum sativum,
Lagecia cuminoides) is this sac entirely unseptated; in a few others
(Heracleum Sphondylium and caucasicum, Sison Amomum, Atthusa cyna-
pium) it is imperfectly septated ; in the great majority of umbellifers the
sac and the layer are divided into a number of chambers. ‘The layer
itself consists of a peculiar substance, the exact nature of which is not
yet determined; but it is neither a carbohydrate, a fatty oil, a mixture
of these, a res.n, nor a caoutchouc-like substance, as is shown by its
microchemical reactions. In some species, between the thick septa
and the parietal layer is a ring of irregular thick-walled vacuoles. In
Conium maculatum, where the vitte are only rudimentary in the ripe
fruit, the peculiar layer is wanting. In one species only, where the
vittz are well developed, Johrenia greca, is the aromatic secretion alto-
gether wanting, and replaced by a solid substance. In Astrantia major

* Bot. Sallsk. Stockholm, March 21,1888. See Bot. Ceutralbl., xxxviii. (1889)
p- 602.

+ Bull. Soc. Bot. France, xxxvi. (1889) pp. 82-5.

{ Arb. Kiew. Naturf. Gesell., ix. (1888) pp. 65-106 (2 pls.). See Bot. Centralbl.,
XXXviil. (1889) p. 792.

§ Bot. Ztg., xlvii. (1889) pp. 341-52, 357-66, 373-9 (1 pl. and 1 fig-).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 663

and Eryngium maritimum, where the fruit is but slightly aromatic, the
vittz have no layer, but instead a fluid secretion.

At a very early period in the formation of the vittz, even in the
flower-bud, substances of two different kinds are exuded from the walls
of the epithelial cells into the vitta, viz. a watery fluid and an ethereal
oil insoluble in water. The vittz themselves are always of schizogenous
origin. The object of the layer above described is clearly to retain the
secretion in the vitta and to prevent its flowing into the surrounding
tissue. The anise oil contained in the vitte of Mceniculum officinale and
Pimpinella Anisum and the caruol in those of Anethum graveolens and
Carum Carui are highly poisonous to birds.

Fruit of Grasses.*—M. H. Jumelle is unable to accept the ordinary
view of the structure of the caryopsis of the Graminee, that it is a fruit
in which there is complete fusion of the integument of the ovule with
the pericarp. He finds no evidence of such a fusion taking place at
any time, but, on the contrary, the pericarp is partly absorbed during
maturation, and the integuments of the seed completely disappear. The
caryopsis is, in fact, an ordinary achene inclosing a single seed without
integuments.

Primula with Anatropous Seeds.;—M. A. Franchet states that one
point of difference between the genera Hottonia and Primula is that in
the former the seeds are anatropous, while they are hemitropous in the
latter. He then describes two Primulas, P. Delavayi and P. vinciflora
from China, having anatropous seeds as in Hottonia. The anatropy of
the seeds is only complete at maturity. In the ovule and young seed
hemitropy is still evident, especially in P. Delavayi. If the ripe seeds
of Hottonia are compared with those of these two Primulas, it is readily
seen that anatropy exists to the same degree, and is present under the
same conditions in the two genera.

Seed of Victoria.{—In pursuance of his researches on the structure
of the Nymphzacee, Prof. G. Arcangeli has now carefully examined
that of the seeds of Victoria regia. He tinds an outer integument and
an inner much thinner one, closely adpressed to the seed. The seed
itself consists of three parts, embryo, endosperm (albumen), and peri-
sperm; and, as in Euryale, Nymphza, and Nuphar, the amylaceous
reserve-material is found chiefly in the perisperm, which is much the
most developed of the three, while the albuminoid and fatty reserve-
materials abound in the embryo, although an albuminoid network is also
present in the perisperm, inclosing the grains of starch.

Borragoid Inflorescence.§ —Herr K. Schumann compares the peculiar
inflorescence, to which he gives the term borragoid, characteristic of the
Borraginee, Hydrophyllacee, Solanaceew, and some Labiatz, with the
true cyme, such as obtains in Ru'a and Echeveria, and finds the differ-
ence not so great as has been maintained by some writers. The
dorsiventral structure occurs also in true cymes. The borragoid is only
a special case of the true cyme, the determining factor of which is the
dichotomous division of the cone of growth, in contrast to the lateral

* Comptes Rendus, evii. (1888) pp. 285-7.

¢ Journ. de Bot. (Morot), ili. (1889) pp. 49-52 (3 figs.).

} Nuov. Giorn. Bot. Ital., xxi. (1889) pp. 286-9. Cf. this Journal, ante, p. 407.
§ Ler. Deutsch. Lot. Gesell., vii. (1889) pp. 52-80 (1 pl.).

664 SUMMARY OF CURRENT RESEARCHES RELATING TO

branching of the true cyme. This is especially seen from an examination
of the double borragoid, like that of Cerinthe.

Leaf of Taxodium.”—Prof. 8. Coulter finds the leaf of Taxodiwm
distichum to differ from that of Pinus sylvestris (agreeing rather with
the young leaves of Pinus) in the following points :—(1) In the less
perfect development of the stomates; (2) in the imperfect development
and indefinite arrangement of the strengthening apparatus, shown by the
absence of the continuous hypodermal layer and the absence of
sclerenchyme from the region of the resin-duct ; (3) in the presence of a
stngle resin-duct, showing imperfect differentiation from the surrounding
tissue ; and (4) in the less complete development of the vascular bundle
and of its elements.

Origin of Rootlets.;—In a very elaborate paper on this subject,
MM. P. Van Tieghem and H. Douliot state that for the origin of rootlets
in Phanerogams, one general and very simple rule may be given. In all
Phanerogams the rootlets proceed from a transverse growth localized in
the pericycle of the mother-root, and their three regions are cut off in
the same manner by two tangential divisions in the group of pericyclic
cells which gather together radially. The position of the lateral root
varies ; it may be situated either opposite the phloem of a vascuiar
bundle, or opposite a ray, or it may either be placed in the middle of a
ray and inserted at the same time on two neighbouring vascular bundles,
or laterally and inserted only on the side of the corresponding bundle.

The existence or absence of a pocket, and its thickness, origin, and
mode of separation, are characters which modify the external aspect of
the rootlet, but are quite subordinate characters, seeing that they vary
not only in allied families, but also in allied genera belonging to the
same family, and sometimes from one species to another in the same
genus, and occasionally from one root to another in the same plant.
Two distinct variations, however, can be traced in the mode of formation
of pockets in Phanerogams: either the desquamation of the epiderm is
partial, as in Dicotyledons (except Nympheacez) and Gymnosperms, or
the desquamation is total, as in Monocotyledons and Nymphzacee.

The authors then describe the origin and development of lateral
roots in Vascular Cryptogams, and state that in this latter group of
plants two great divisions can be recognized, the one comprising the
Filicine, and the other Lycopodium and Isoetes. In the first division
the root is formed in the innermost layer of the cortex, that is, in the
actual endoderm. Filicinee are, therefore, endodermorhizal and mona-
crorhizal. In the second division the root is formed in the outermost
layer of the central cylinder, that is, in the pericycle ; Lycopodium and
Tsoetes are, therefore, pericyclorhizal and triacrorhizal.

If we compare these two groups with Phanerogams, it will be séen
that the second resembles them in all points, while the first differs
precisely to the same extent as it differs from the second. There are
then two types of formation and growth of roots in vascular plants. If
we divide Vascular Plants into two great groups, the first would include
Phanerogams, Lycopodium, and Isoetes ; while the second would include
all Vascular Cryptogams, with the exception of Lycopodium and Isoetes.

The authors conclude this exceedingly lengthy paper by describing

* Bot. Gazette, xiv. (1889) pp. 76-81, 101-7 (1 pl. and 1 fig.).
+ Ann. Sci. Nat., viii. (1888-9) pp. 1-660 (40 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 665

the origin, internal growth, and development of the other endogenous
members, the general conclusions being that in Phanerogams the
rootlets, lateral roots, and terminal roots or buds all originate in the
pericycle, while in Vascular Cryptogams they originate in the
endoderm.

Composition of the Tubercles of Stachys tuberifera.*—M. A. Planta

states that the tubercles formed on the swollen internodes of the subter-
ranean branches of Stachys tuberifera are peculiarly interesting on account

of their chemical composition.

The following is the analysis :—

7 Fresh. Dry.
Water SEEDY pace cps 78°33 a
Broiwids: 2 ae” OS 1°50 6°68
PG Co: Sh ae oe iLo(s7¢ To
pgm Wats © Be. Ny 10k Ses 0-18 0-82
Carbohydrates .. eibe Sh 1OTL
Welintnges. “i. oes OTs Bae)
(20 Tal ke Gee eee 1-02 4-70

100-00 100-00

The tubercles contain therefore 21°67 per cent. of dry substance, the
most important being the carbohydrates, the principal of which is a
new substance, intermediate between starch and sugar, which he calls
galactane.

Origin of the Haustoria in Parasitic Phanerogams.{—M. Granel
states that in none of the parasitic Phanerogams which he has studied
does the piliferous layer contribute to the formation of the haustorium,
but that this organ originates more deeply in the cortical parenchyme.
The tissues thus formed join themselves more or less slowly to the
endoderm and to the pericycle, which in their turn divide in order to
attach the central cylinder to the vascular structures of the haustorium.
In stem-parasites (Cuscuta) the progress of the development is just the
same. ‘lhe morphological nature of these haustoria has been much
discussed, and for long they were grouped with lateral roots or rootlets.
The author, however, states that their origin is totally different. They
are from the first exogenous formations, and afterwards unite with
structures proceeding from the endoderm and pericycle.

Criticizing this paper, M. Leclerc du Sablon f{ states that M. Granel
has studied, not the development of the haustoria, but certain definite
forms, which are presented in roots of various ages, of haustoria in which
the growth has been more or less abortive.

Haustoria of Rhinanthacee.§—Herr L. Koch has closely followed
out the germination and development of Rhinanthus minor. He finds
that the seeds germinate freely, but very slowly, and only in the spring.
If the seedlings do not encounter a suitable host-plant they soon perish,
unless a large number grow close together, when they put out a number
of haustoria into one another, and develope to the flowering stage, but

* Rev. Gen. de Bot. (Bonnier), i. (1889) pp. 85-7 (1 fig.).
+ Journ. de Bot. (Morot), iii. (1889) pp. 149-53 (1 pl.).
t T. ¢., pp. 183-4.
pe Move f. Wiss. Bot. (Pringsheim), xx. (1889) pp. 1-37(1 pl.). Cf. this Journal,
, p- 80.

1889, oA

666 SUMMARY OF CURRENT RESEARCHES RELATING TO

only in a weakly condition. They grow vigorously only when they meet
with host-plants, especially grasses.

The roots of Rhinanthus are but very sparsely supplied with root-
hairs, and consequently have but little power of independent nutrition.
The haustoria are formed at an early period, and are, like those of
Melampyrum, exogenous. They penetrate the root of the host by means of
a sac-like cell not unlike the apical cell of a growing-point, which breaks
through the endoderm of the vascular bundle of the host and enters the
thick-walled xylem, probably with the aid of a solvent excretion. The
process is somewhat different according as the host-plant is a mono-
cotyledon or dicotyledon. The haustoria contain no starch, but, on the
other hand, minute granular or rod-like albuminous bodies, which —
gradually fill up the tissue, but are used up by the time of flowering,
and closely resemble the “bacteroids” of the tubercles of the roots of
Leguminose.

Lhinanthus is, therefore, in contradistinction to Melampyrum, a true
parasite; but it may also live toa certain extent saprophytically. The
cells of the parasite are in contact with a homogeneous yellow mass resu!t-
ing from the decomposition of the cells of the host; the vascular bundles
of the host being also to a large extent destroyed. From the margin
of the haustorium cells also advance towards and penetrate the cortex
of the host and destroy it, applying themselves to and embracing the
destroyed portion somewhat in the manner of root-hairs. Parasitism 1s,
therefore, necessary for the vigorous growth of Rhinanthus, but the plant -
is, like the mistletoe, only a partial parasite, carrying on an independent
assimilation of its own, and not inflicting any serious injury on the host.

M. Granel* dissents to a certain extent from the observations of
Leclere du Sablon and Koch on the origin of the haustoria in Melam-
pyrum and Rhinanthus, inasmuch as he asserts that they do not spring
from the piliferous layer, but, in accordance with his previous observa- —
tions on Orobanche and the Santalacez, from the cortical parenchyme.
He agrees, however, with those authorities as to the morphological
nature of these organs. They are of exogenous origin, not springing,
like the rootlets, from the pericycle, and they do not present the least
trace of root-cap; the arrangement of their vascular system is also very
different from that of roots.

Modifications in the Roots of Grasses growing in Water.;—
M. Devaux describes certain modifications which had taken place in the
roots of Lolium and Holcus mollis when grown in water. In Lolium the
development of the roots at first appeared normal; but, after having
attained a length of some centimetres, a large number were observed in
which the growing point, instead of continuing its descending direction,
inclined towards the side, then raised itself, and finally followed a
helicoid line of growth in the liquid. In Holcus mollis the root-hairs
preserved their normal form, but a number of tubercles were developed,
the radicles being arrested in their development.

* Comptes Rendus, eviii. (1889) pp. 367-9.
+ Bull. Soc. Bot. France, xxxvi. (L889) pp. 76-81.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 667

B. Physiology.*
(1) Reproduction and Germination.

Diclinism and Hermaphroditism.t—Starting from an examinaticn
of the phenomena of reproduction in Limnobium stoloniferum (Hydro-
charidee), Herr U. Dammer concludes that the original condition in
flowering plants is that of moncec’sm, from which dicecism and herma-
phroditism have been derived, and that the highest conceivable condition
is where heterostyled dichogamous hermaphrodite are densely aggregated
along with diclinous flowers, such as we find in the capitula of Com-
posite ; pollination being here secured, but self-fertilization prevented.
This order he regards, therefore, as the highest existing form of
Dicotyledons, and the Orchidexw of Monocotyledons, while the Hydro-
charidez, in which hermaphroditism is very rare, represents one of the
oldest branches of the latter group. A detailed description follows of
the anatomy, morphology, and biology of the species named.

Trimorphism of Oxalis.t—Mr. W. G. Eliot and Prof. W. Trelease
give a series of measurements of the length of style and filaments in the
three forms of the American trimorphic species of Oxalis. They regard
trimorphism as a device for surer and more abundant cross-fertilization.
The relative number of long-styled, short-styled, and mid-styled forms
observed was about in the proportion of four, five, and eleven.

Pollination by Lepidoptera.s—Sig. G. E. Mattei describes the
adaptation of the proboscis of lepidoptera for obtaining the honey of
flowers; and of the flowers themselves for receiving the visits of the
insects. He enumerates 132 sphingophilous species, characterized by
blossoming in the evening or night; by their strong odour, especially
at night; white or yellowish colour; long, slender, often curved tubular
corolla or spur, yielding abundance of honey; viscid or united pollen-
grains; and by their usually projecting stigma and stamens, often with
very motile filaments.

Perforation of Flowers by Insects.||— Mr. L. H. Pammel, after
describing the mode of fertilization of Phlomis tuberosa, enumerates the
instances in which the corolla of flowers is known to be perforated by
insects or birds in order to obtain the nectar. The insects with which
this is habitual are mostly species of Bombus, the hive-bee most
commonly making use of perforations already made by other insects.
The tendency is to produce sterility by preventing pollination in the
ordinary way, though this is by no means always the case. The per-
foration of the corolla is usually attributable to the non-adaptability of
the insect to the flower, and the insect often uses considerable ingenuity
in perforating the flower, attacking it in close proximity to the nectary.
This is individual and not inherited experience on the part of the insects.
Phlomis tuberosa and Symphytum officinale ave examples of flowers which
are abundantly perforated, and are yet very productive.

* This subdivision contains (1) Reproduction and Germination; (2) Nutrition
and Growth (incluiing Movements of !luids); (3) Irritability; and (4) Chemical
Changes (including Respiration and Fermentation).

+ ‘Beitr. z. Kennt. d. veget. Organen v. Limnobium stoloniferum Griseb., nebst
einigen Betrachtungen iib. d. phylogenetische Dignitaét v. Diclinie u. Hermaphro-
ditismus,’ 17 pp., Berlin, 1888. See Bot. Centralbl., xxxviii. (1889) p. 743.

t Trans. Acad. Sci. St. Louis, v. (1888) pp. 278-91 (3 figs.).

§ ‘I lepidotterie e la dicogamia,’ Bologna, 1888, 48 pp. See Bot. Centralbl.,
xxxviii. (1889) p. 792. || Trans. Acad. Sci. St. Louis, v. (1888) pp. 241-77 (2 pls.).

Saw

668 SUMMARY OF CURRENT RESEARCHES RELATING TO

(2) Nutrition and Growth (including Movements of Fluids).

Development of Annual Plants.*—M. H. Jumelle describes the
variations which the different members of an annual plant undergo
according to their age, and to the external conditions to which they are
subjected. From germination to maturity five principal periods may be
distinguished. In the first, or germinating period, there is a simple
migration of matter from the cotyledons towards the hypocotyledonary
parts, and the plant not only does not assimilate, but loses some of its
dry weight by chemical transformations. In the second period assimila-
tion commences. The cotyledons lose a further portion of their sub-
stances to the hypocotyledonary, and also to the epicotyledonary parts
which now begin to develope. The third period is marked by the dis-
appearance of the cotyledons, and there is a rapid transportation of
substance from the hypocotyledonary axis towards the summit of the
plant. In the fourth period the flowers appear, and a fresh migration
of matter takes place towards the summit of the plant. The fifth period
commences after flowering. There is a considerable increase in dry
weight in the root, stem, and leaves; and the absorption of mineral
matter is very active. The quantity of water follows less rapidly and
in different proportions these variations of dry substance. In the

cotyledons, on the contrary, it tends to augment while the dry material
diminishes.

Influence of External Agents on the Polarity and Dorsiventral
Structure of Plants.;—M. Kolderup Rosenvinge in the first place de-
scribes various experiments made with the spores of the Fucacee, in
order to determine the influence of external agents on polarity. The
following are the most important conclusions:—(1) The polarity of
the spores which germinated (that is, the determination of the point
where the rhizoids and the apical point appeared) can be determined by
diverse external agencies; (2) Light may influence the orientation of
the first septum ; (3) Light determined the polarity of the plants in all
the species studied except Fucus serratus. The sensibility to light was
greatest in Pelvetia canaliculata ; (4) Gravitation had no influence on
the polarity of the plants; (5) Contact with a solid body had no
influence on the polarity of the plants; (6) A difference in the quantity
of oxygen on the different sides of the spores affected the polarity,
rhizoids forming on the side where the oxygen was most feeble; (7) In
all the species the polarity could be determined exclusively by internal
causes, which seemed independent of the orientation of the oosphere in
the ovgone.

In the second part of the paper the author discusses the dorsiventral
structure of plants. It is well known that dorsiventral organs are
ordinarily plagiotropic ; nevertheless shoots have been found in Vicia
Fuba and several species of Begonia, which grow vertically, although
they have a pronounced dorsiventral structure. Centradenia floribunda
furnishes an example of a dorsiveutral structure which is produced by an
external influence, and which can be reversed by inverse action of the
cause which produced it. In none of the other plants studied could the

* Rey. Gén. de Bot. (Bonnier), i. (1889) pp. 101-22, 195-211, 258-79, 318-29;
and Bull. Soc. Bot. France, xxxvi. (1889) pp. 72-6. :

+ Rev. Gén. de Bot. (Bonnier), i. (1889) pp. 53-63, 123-35, 170-4, 244-55,
304-17 (19 figs.).

* ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 669

dorsiventrality be reversed. In certain plants the orientation of the
dorsiventral structure of lateral branches can be determined by external
agencies (ex. Columnea Schiedeana, Scutellaria albida). Often, how-
ever, it is independent of external agencies, and is determine] solely by
the mother-axis. In certain plants the lateral branches are dorsi-
ventral, the primary axis remaining radial (ex. Cullisia delicatula,
Cyanotis cristata) ; more often, however, the primary axis itself becomes
dorsiventral sooner or later. In all the plants studied in which the
primary axis became dorsiventral, except Cicer arietinum, the dorsi-
ventral structure of this axis could be determined by light or gravita-
tion. When the dorsiventral structure is determined by light, the
illuminated surface usually becomes superior, and in normal conditions
faces upwards.

One-sided Hardness of Wood.*—According to Herr P. Kononczuk, it
is especially common in conifers for the annual rings to be very much
thicker on one side of the branch or stem than on the other side; and
the wood is then harder on that side where the rings are broadest. In
the case of horizontal or oblique stems or branches, this is always the
case on the under side, and is due to gravitation; in the case of erect
stems, it is found on that side which produces the greatest number of
branches, i. e. that one most exposed to the air, or especially on the east
or south side.

Influence of Exposure on the Growth of the Bark of Conifers.t—
From the result of a large number of observations, M. E. Mer finds that
in pine-trees the sides most exposed to the heat of the sun, i.e. the south
and west, have a thicker bark relatively to the thickness of the wood
than those not so fully exposed. Exposure to heat and light retard the
formation cf wood relatively to that of the bark.

Chlorophyllous Assimilation and Transpiration.t—M. H. Jumelle
describes certain experiments made with the object of ascertaining whether
there exists any relation between the two phenomena of chlorophyllous
assimilation and transpiration ; in other words, whether, if one of them
is arrested the other is modified. The conclusions of the author are
that the presence of carbon dioxide in the air, or the presence of potash,
which might aceclerate the transpiration by drying the air, has really
no sensible effect on transpiration; but that if the function of the
chlorophyll persists while assimilation is suspended, the intensity of
the transpiration is augmented. This accords with the theory of
Weisner, who maintains that a portion only of the light which traverses
the chlorophyll takes part in the decomposition of the carbon dioxide,
the heat provided by the other portion producing the transpiration ;
that is, if assimilation is suppressed, that portion of the luminous ray
which serves for the decomposition of the carbon dioxide remains free.
The result is that more heat is developed, and consequently a larger
amount of transpiration takes place.

Influence of Mineral Substances on the Growth of Plants.s—By
contrasting the development of plants (chiefly lupins) grown in distilled

* Jahrb. St. Petersb. Forstinstit., ii. (1888) pp. 41-56 (4 pls.). See Bot.
Centralbl., xxxviii. (1889) p. 794.

t Journ. de Bot. (Morot), iii. (1889) pp. 52-9, 77-83, 106-12, 114-21, 136-40.
Cf. this Journal, 1888, p. 762.

t Rey. Gén. de Bot. (Bonnier), i. (1889) pp. 37-46.

§ Comptes Rendus, eviii. (1889) pp 466-8.

670 SUMMARY OF CURRENT RESEARCHES RELATING TO

water with those grown in ordinary soil, M. H. Jumelle comes to the
conclusion that the presence of mineral substances favours the produc-
tion of parenchyme rather than that of supporting tissue. During the
earliest stages of development no difference could be detected in the
development of the sets of plants grown under different conditions; but
after about 60 days, when the number of leaves exceeds five or six, in
the former set the leaves were found to be small and bright green, the
internodes long and slender; in the latter the leaves were large and
yellowish-green, the internodes short and thick. The difference appears
to be due less to the absence of the salts themselves than to the accom-
panying diminution of the water of constitution.

Trophilegic Function of Leaves.*—Prof. G. Arcangeli calls atten-
tion to the observations of Goebel t on the heterophylly of the leaves of
tropical species of Platycertum and other ferns. He points out that the
presence of leaves of a shell-like form is not peculiar to ferns, but occurs
also in many flowering plants; the function of these leaves being, if not
the direct absorption of water, the collection of food-material for the use
of the plant. He proposes for this function, to which he thinks too
little attention has been paid, the term trophilegic.

Movement of Sap in the Wood.{—According to Prof. R. Hartig,
the movement of fluid in woody stems takes place chiefly in the outer
layers of alburnum, the inner layers of alburnum forming a reservoir
where it is stored up when not in motion. In Conifers the tracheides’
together with the medullary rays are certainly the organs of conduction
from one layer to another; while in Dicotyledons it is probably the
vessels in which this movement of the sap takes place. The vessels,
which diminish the weight of the wood by their size and by the thinness
of their walls, run downwards from the leaves through the corresponding
annual ring to the root. In a beech 143 years old the number of vessels
in the youngest annual ring was estimated at 116,000.

Dr. Hartig further replies § to Wieler’s criticisms || on his previously
published results, repeating his reasons for coming to the conclusion
above stated as to the ordinary course of the movement of fluids.

Exchange of Gases in Submerged Plants. —M. H. Devaux has
studied, by means of a mechanical apparatus, the mechanism of the
exchange in gases in plants entirely submerged, the experiments having
been made chiefly on Hlodea canadensis.

The escape of gases may take place either by diffusion through the
cell-walls or in the form of bubbles; the former mode being very
analogous to that which would take place across an immobile liquid
plate. ‘lhe entrance by diffusion takes place in the same way, whether
the plant grows in air or in water. Bubbles disengaged from the
interior of the plant are always the result of injury; and from an
examination of these it was found that the internal atmosphere of sub-
merged plants has very nearly the same composition as the external air,

* Nuov. Giorn. Bot. Ital, xxi. (1889) pp. 272-6.

+ Of. this Journal, 1888, p. 90.

+ SL. Bot. Verein Miinchen, Feb. 11, 1889. See Bot. Centralbl., xxxvii. (1889)
». 418.
§ Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 89-94.

\| Cf. this Journal, ante, p. 251.

4; Ann. Sci. Nat, (Bot ), ix. (1889) pp. 35-180.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 671

the change produced by respiration being compensated by other changes
resulting from diffusion. In addition to bubbles disengaged from inter-
cellular spaces in the interior of the plant, there are often others, always
very small, on the surface of submerged plants; tlese result entirely
from the air dissolved in the water, and occur only on plants without
intercellular spaces, especially on Alge. The air in the intercellular
spaces is subject to constant variations of pressure. These intercellular
spaces are formed in the tissue at a very early period, occurring even
near the extremity of the cone of growth of the stem.

As a general result, the author states that there always exists air
dissolved in all the constituent parts of a submerged plant, and that the
gas in every cell is subject to a uniform pressure, corresponding nearly
to that of the surrounding air.

Absorption of Water by Leaves.*—In order to determine whether
plants can absorb water through their leaves, Herr W. Chmielewskij
arranged branches of a number of shrubs and trees, so that a portion of
their leaves was immersed in water, the remainder being exposed to the
air. In all cases except one, the leaves immersed in water remained
fresh for a longer period than those exposed to the air. ‘lhe absorption
of water does not take place through the stomates, but equally through
both surfaces of the leaf; the stomates remained filled with air.

Changes of Substance and Force connected with Respiration.;—
Pursuing his investigations on this subject, Dr. H. Rodewald again finds

a CO
the average value of the relationship er to be very near unity. In
2

the case of the cabbage, which was especially the subject of investiga-
tion, the author believes deviations from this average to be due to
other chemical processes going on side by side with that of respiration.
An absorption of energy must necessarily take place in the conversion
of cellulose or phellogen into grape-sugar, since the heat evolved in
combustion is greater in the case of cellulose than in that of grape-
sugar. The same must be the case when grape-sugar is converted into
starch, and possibly also in the splitting up of albuminoids.

y. General.

Chlorosis.{—The disease of chlorosis, characterized by the pale
yellow colour of the leaves and the stunting of the branches, which is
very destructive to vineyards, is attributed by M. E. Petit to an excess
of moisture in the soil, filling the cavities which ought to be full of air.
It is, in fact, the outward manifestation of the choking of the roots.
Various remedies are discussed.

Vuillemin’s Vegetable Biology.$—This work is divided into three
parts :—The life of the cell; the life of the individual; and the social
life of plants. The first chapter is devoted to the cell in general. The
cell is formed by two kinds of microsomes, cytosomes and caryosomes,

* Arb. Neu-russ. Naturf. Gesell., xiii. (1888) pp. 123-34. See Bot. Centralbl.
XXXvili. (1889) p. 790. 5

+ Jahrb. f. Wiss. Bot. (Pringsheim), xx. (1889) pp. 261-91. Cf. this Journal,
1888, p. 771.

~ ‘La chlorose: Rech. d. ses causes et d. ses remédes,’ Bordeaux, 1888, See
Bull. Soe. Bot. France, xxxvi. (1889), Rev. Bibl., p. 84.

§ ‘La Biologie végétale,’ 16mo, Paris, 1888, 360 pp. and 82 figs.

672 SUMMARY OF CURRENT RESEARCHES RELATING TO

generally localized in two distinct regions, and constituting the cyto-
plasm and the caryoplasm or nucleus. On contact with a foreign body
the cytoplasm takes on itself special characters, and becomes a dermato-
plasm or membranous layer. Cytodes are elements in which the
caryosomes are not grouped into a nucleus. The cell-membrane is
regarded by the author as always an intracellular derivative.

The thallus springs from an isolated cell or spore. The body of
fungi is generally formed of cells reduced either to nucleus or to cell-
wall; this structure is not properly non-cellular; the author terms it
apocyty. A more highly organized type is the result of fecundation.
The elements of the embryo are differentiated from the first into an
epithele or epiderm and an apothelial mass. The epithelial body,
represented in mosses by the sporogone, is the point of departure of the
vascular body of the higher plants. Certain aberrant types of vascular
cryptogams, such as ferns, present a stage of suppressed embryo, the
oosphere giving rise directly to the vascular members; this condition is
termed by M. Vuillemin apoembryony.

In the portion of the work devoted to the life of the individual, the
organs of fixation, support, and protection are first treated of, followed
by the phenomena of absorption and excretion. These two processes he
regards as opposites, the latter being concerned with everything which
the plant gives out to the environment, whether ponderable matter or
mechanical work. The author then deals with respiration, and the
functions of specific lives, which he classifies under renovation, multi-
plication, fusion, conservation, and dispersion.

Under the head of the social life of plants are discussed the relations
between individuals of the same species, and especially the sexual
relations, and finally, the relations between individuals of different
species, including epiphytism, hybridity, grafting, parasitism, and
symbiosis, particularly the algo-lichen theory, and the phenomenon of
mycorhiza.

B. CRYPTOGAMIA.

Cryptogamia Vascularia.

Psilotum and Tmesipteris.*—Dr. W. A. Haswell has carefully
examined the structure of Psilotum triquetrum and Tmesipteris tannensis,
natives of New South Wales.

Tmesipteris tannensis grows most commonly on the trunks of tree-
ferns, deeply buried in the fibrous coating of the stem, less often creeping
along the ground, The stem always branches dichotomously. It has
a central bundle of small scalariform and reticulated tracheides, without
any definite bundle-sheath ; but is surrounded by from one to four layers
of cells filled with a solid brown substance. In the leaf-bearing portion
the xylem portion is central, and is surrounded by phloem. The cortical
tissue is strongly sclerenchymatous in its outer part. The leaves
are oval and unsymmetrical at the base, with a single unbranched mid-
rib, which is produced at the extremity into a spine-like point. The
sporanges are borne on special lateral branches which terminate in bracts
similar to the ordinary leaves, but smaller. Hach sporange has two
loculi; the spores are oval and compressed.

Psilotum triquetrum is shrub-like in habit, with very minute leaves.

* Proc. Linn. Soc. N. §. Wales, ii. (1888) pp. 1025-31.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 673

The single central vascular bundle of the stem is also concentric, and
is inclosed in a bundle-sheath which is surrounded by a layer of brown
tissue similar to that of Tmesipteris, but less strongly developed.
Stomates are abundant on the stem. Each sporange contains a large
number of spores.

All attempts to rear the prothallium failed in both genera.

Calamariee.*—Herr D. Stur gives a detailed account of the
morphology of this group of Fossil Vascular Cryptogams, including
their roots, rhizome, true stem, branches, and leaves. They differ from
the recent Equisetacex, to which they are otherwise nearly allied, chiefly
in the property of forming wood. The branches are also much more
polymorphic than those of living Hquiseta. The Asterophyllitez and
Annulariee are homomorphic, the Sphenophyllee heteromorphic
branches ; the homomorphic branches bore Bruckmannia-fructifications
with microspores, the heteromorphic branches Volkmannia-fructifications
with megaspores. ‘'T'wenty-four species are described in detail, arranged
under the genera Calamites, Asterophyllites, Bruckmannia, Annularia,
Cingularia, Volkmannia, and Sphenophyllum.

IMuscineee.

Peristome.|—M. Philibert continues his studies on the peristome,
and now describes the differences between the Nematodontexw and the
Arthrodontez, and discusses certain groups which are transitional be-
tween these two. The Tetraphidez closely resemble the Polytrichacez.
One important difference, however, may be found in the peristomial
fibres; in the Polytrichacee these fibres are perfectly simple and undi-
vided, and continue without interruption the whole length of the tooth,
while in the Tetraphidee they only occupy a portion of the length of
the peristome. The author then points out how very different is the
structure in these two families to that found in the Arthrodontex ; and
concludes by describing the two families Buxbaumiacee and Encalyptee,
which present an intermediate structure between the Nematodontee and
the Arthrodontezx.

Encalypta longicolla and E. brevicolla are especially interesting to
study in order to determine the origin of the peristome. The structure
of the peristome in these two species nearly approaches that in the
Arthrodontez ; and in another species, HE. apophysata, we have a type
of peristome which seems exactly intermediate between the Arthrodontese
and Nematodontese. A gradual scale may be formed, beginning with
Tetraphis, and passing first through Encalypta longicolla, then through
the diverse forms of E. brevicolla and apophysata, and finally reaching
Ei. procera and EH. streptocarpa, where the double peristome of the Arthro-
dontez is completely developed.

Inflorescence of Orthotrichum.{—Herr A. L. Grénwall points out
that in various species of Orthotrichum, as, e.g. in O. speciosum, three
different positions of the male inflorescence may occur in the same
species, viz. :— Axillary, pseudo-lateral (at the base of the fertile branch),
and terminal.

* «Die Calamarieen d. Carbonflora d. Schatzlarer-Schichten,’ Wien, 1887 (26 pls.
and 43 figs.). See Bot. Centralbl., xxxviii. (1889) pp. 779 and 797.

+ Rev. Bryol., xvi. (1889) pp. 1-9, 39-44. Cf. this Journal, ante, p. 257.

t Bot. Ver. Lund, Mareh 27, 1888. See Bot. Centralbl., xxxviii. (1889) p. 759.

674 SUMMARY OF CURRENT RESEARCHES RELATING TO

Colouring-matter of Sphagnacese.*—According to M. F. Gravet, the
red or orange colouring-matter of the male branches and of the capsules
of the different species of Sphagnum is caused by the presence of tannin,
produced under the action of light, although the male branches are also
coloured even when growing in the shade.

Alge.

Vacuoles in Alge.t—Herr F. A. F'. C.Went describes the occurrence
of vacuoles in the reproductive and propagative organs of a number of
Alge belonging to the Floridex, Fucacee, Pheosporee, Cladophorex, and
Codiez. He finds them to agree with those previously observed in the
vegetative organs, in the presence of a living tonoplast, and in the fact
that the normal vacuoles invariably result from the division of those
already in existence. The organs in which they were detected are,
among others :—the sporanges of Codiuwm, the zoospores of Chzetomorpha,
the sporanges of Sporochnus, the oogones and antherids of Cystosira and
Sargassum, the tetraspores, pollinoids (spermatia), and carpospores of
several Floridex, and many others.

Antherids and Pollinoids of Floridee.{—M. L. Guignard continues
his account of the male sexual elements in Cryptogams with a study of
these organs in the Floridee. Their structure and mode of origin are
in general terms the same throughout the class. The antherid either
springs directly from a single cell of the thallus, or results from more
or less numerous bipartitions of the antheridiferous cell. The pollinoid
is a round or ellipsoidal body, not absolutely naked, but inclosed in a
very thin investment, which does not, however, give the reactions of
cellulose; it escapes by the gelification of the apex of the antherid.

In Batrachospermum, Nemaleon, and Helminthora, we find the simplest
structure and arrangement of the antherids, which spring by budding
from the extremities of peripheral filaments of the thallus. Hach polli-
noid has a nucleus, but no nucleole. In Callithamnion roseum the struc-
ture is no way essentially different. In Griffithsia corallina the antherids
are developed at the extremity of particular branches of the thallus, in
the form of tufts.

In Polyides rotundus the antherids are formed in tetrads on filaments
resulting from the prolongation of cortical cells. Their mode of forma-
tion recalls that of tetraspores, or even of the pollen-grains of flowering
plants. In Chondria tenuissima the antherids result from the trans-
formation of hairs which cover the branches, and are produced in a
dense row.

In the Melobesiacese and Corallinacez the form of the antherids and
pollinoids is very remarkable. In Melobesia membranacea the male con-
ceptacles are clothed with hairs, each of which becomes segmented into
a row of antherids. The greater part of the contents of each antherid
contracts into a pollinoid, each of which, when it escapes, is furnished
with two appendages having the appearance of wings, the remains of the
walls which divided the filaments into antherids. In Corallina officinalis
the antherids are produced in tufts, and are of a very elongated club-
shape; and the pollinoid, when it escapes from the antherid, is an oval

Rey. Bryol., xvi. (1889) p. 37.

4, ?
+ Bot. Ztg., xlvii. (1889) pp. 197 206. Cf. this Journal, 1888, p. 981.
+ Rey. Gen. de bot. (Bonnier), i. (1889) pp. 175-86 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 675

body with a very slender tail-like appendage, the remains of the proto-
plasm of the narrow stalk-like portion of the club-shaped antherid. The
body of the pollinoid is inclosed in a very thin membrane which does
not include the tail.

Antherozoids of Fucacew.*—M. L. Guignard has investigated the
mode of development of the antherozoids of several species of Fucus,
Pelvetia, Halidrys, and Cystosira, which he finds to agree in all essential
particulars ; Fucus serratus may be taken asatype. Each antherid gives
birth to sixty-four antherozoids; the nucleus of the antherid divides
first of all, by repeated karyokinetic bipartition, into sixty-four nuclei,
distributed uniformly through the protoplasm. In forming the anthero-
zoids, the protoplasm divides and collects round the nuclei; and to each
nucleus is attached a chromatophore, at first uncoloured, which becomes
subsequently the coloured so-called “ pigment-spot.” The two cilia of the
antherozoid are formed from a delicate peripheral protoplasm-ring. The
anterior cilium is fixed, for a portion of its length, to the body of the
antherozoid, and serves, when in motion, as an oar; the posterior cilium
is inserted at the point of contact of the “ pigment-spot” with the proto-
plasm, is twice as long as the anterior cilium, and serves as a rudder.
The mature antherozoid is pyriform, and is, in its origin, a naked cell
provided with two cilia and with a “ pigment-spot”; and differs there
fore in its homology from that of the Characeef and other higher Crypto-
gams, which is derived from the nucleus only of the mother-cell.

Ectocarpus.{—M. EH. Bornet adopts Kjellman’s distribution of the
species of Ectocarpus among three gencra,—Isthmopiea, in which the
unilocular sporanges are partially buried in the frond; Kctocarpus, in
which they are entirely external; and Pylaiella, in which they are
interealary, in a longitudinal row To the last section belong EF.
fulvescens, Hooperi, and wanus ; and he now gives a detailed description
of Pylaiella fulvescens. 'The only known mode of propagation is by
zoospores contained in unilocular zoosporanges. These are the largest
known among the Pheeosporee, measuring 13-17 » in thickness, and
20-35 p in length, resembling those of Cutleria multifida. They have
two unequal vibratile cilia; the longer one, pointing forwards, does not
exceed the length of the zoospore ; they germinate without conjugation.
The species is also remarkable from the protoplasmic cell-contents
being arranged in stars, resembling the appearance in Zygnema except
in colour.

Desmarestia aculeata.S—Herr EH. Séderstrém gives a careful
description of the anatomical structure of this seaweed. The stem
springs from the base of the true thallus or attachment-disc, and
branches regularly. The so-called “thorns ” are the result of the arrest
of growth of certain lateral branches, and afterwards fall off. Some of
the branches are clothed with very delicate silky hairs, which result
simply from very fine branching of the thallus, and contain abundance
of chlorophyll; they also are deciduous, and must be regarded as organs
of assimilation. Besides these lateral hairs, the young branches also

* Comptes Renduas, eviii. (1889) pp. 577-9; and Rev. Gén. de Bot. (Bonnier), i.
(1889) pp. 137-45 (1 pl.).

+ Cf th's Journal, unte, p. 417.

t Rev. Génu. de Bot. (Bonnier), i. (1889) pp. 1-10 (1 pl.).

§ Bib. Svensk. Vet.-Akad. Handl., xiv., Afd. iii, (188) No. 3 (16 pp and 1 pl.).

676 SUMMARY OF CURRENT RESEARCHES RELATING TO

terminate in hairs which are likewise branched. Growth takes place
from the activity of a growing point situated at the point of junction of
the thallus and the terminal hair. In the mature thallus three primary
tissues may be distinguished, viz. :—(1) the assimilating-tissue, which is
outermost, and consists of 8 or 4 layers of cells; (2) the intermediate
tissue (Fiillgewebe), composed of larger cells, with thicker walls;
and (8) the central cylinder, consisting of only a single row of
cells. Of these the second, which constitutes the principal mass of the
thallus, gives birth to two new secondary tissues, the hyphal tissue or
conducting hyphe, and an inner assimilating tissue.

Delamarea, a new genus of Pheosporee.*—In the Algz collected
in the island of Miquelon by Dr. Delamare, M. P. Hariot finds a
pheeosporous seaweed, which he makes the type of a new genus, named
after the collector, with the following diagnosis :—Thallus cylindraceus,
tubulosus, simplicissimus, subcoriaceus, fibris radicalibus affixus, stratis
duobus cellularum contextus; cellulis interioribus majoribus elongatis,
versus peripheriam minoribus et brevibus, corticalibus in paranemata
inarticulata saccata libera demum evolutis; sporangia unilocularia ovata,
magna, inter paranemata per totam superficiem thalli sparsa; sporangia
plurilocularia. The species described, Delamarea paradoxa, resembles
certain Chordariacee in its fructification and the structure of its frond,
but is distinguished by its non-articulated paraphyses. It differs from
Scytostphon in having both multilocular and unilocular sporanges, and in
its attachment to the substratum by means of articulated filamentous
rhizoids instead of a lobed disc.

Pheodermatium.}—Dr. A. Hansgirg describes a new genus of fresh-
water Pheeophyces, Pheodermatium, with the following diagnosis :—

Thallus submembranaceus, parvus, punctiformis v. plus minus in
substrato expansus, e cellulis pluristratosis (initio unistratosis) pseudo-
parenchymatice coherentibus constitutus. Cellule vegetative rectangu-
Jares v. polygone y. subspherice, in cytoplasmate chromatophorum
laminiforme parietale, luteo- v. aureo-fuscescens et guttas (granula?)
oleose nitentes includentes, membrana crassiuscula achroa subhomogenea
preedite. Membrana in mucum gelatinosum mutata, cellule modo
Syngeneticearum in statum palmellaceum transeunt. Propagatio fit
bipartitione cellulorum in statu palmellaceo (zoosporee non vise). The
only sp., P. rivulare, was found in small streams in Bohemia, attached
to a Chantransia and coated with lime.

Frond of Chordariacez.t—According to Prof. F. R. Kjellman, the
frond of species belonging to this family of seaweeds, although uniform
throughout the family in its mature form, yet belongs, according to the
history of its development, to four different types, as represented in (1)
Chordaria and Leathesia, (2) Elachista, (3) Scytothamnus and Coilodesme,
and (4) an undescribed genus from the Japanese seas.

Distribution of Desmidiacee.s—Herr R. Boldt describes in detail
the 125 species of desmids found in Greenland, including several new

* Journ. de Bot. (Morot), iii. (1889) p. 156 (1 fig.).

+ Notarisia, iv. (1889) p. 658.

{t Naturv. Studentzalsk. Upsala, Feb. 9, 1888. See Bot. Centralbl., xxxviii.
(1889) p. 697.

§ Bih. K. Svensk. Vet.-Akad. Handl., xiii. (1888) Afd. 3, Nos. 5 and 6, 158 pp.
and 4 pls. See Bot. Centralbl., xxxvili. (1889) p. 736.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 677

species. From a comparison of these with the desmid flora of other
northern countries, he comes to the following conclusions on the
distribution of the Desmidiacee.

The desmid-flora of Greenland is very nearly related to that of
other neighbouring countries, especially Scandinavia. Only one arctie
species occurs in Nova-Zembla, Spitzbergen, and northern Greenland which
is well distinguished from that of more southern countries. The flora
of Norway agrees more closely with the arctic flora than does that of
Sweden and Finland. The constitution of the desmid-floras of Spitzbergen
and Greenland does not favour the theory of an interchange of species
between these countries: but both can be well explained on the
supposition of a previous land-connection between these countries
and the continent of northern Europe.

Volvox globator.*— According to Drs. M. L. Mallory, G. W. Rafter,
and J. EH. Line a peculiar odour and taste of fresh fish which has been
observed in the water of the Hemlock Lake, near Rochester, N.Y., is
due to the presence of vast quantities of Volvow globator, though whether
in the living state or in process of decay they are unable to say.

Fungi.

Conjugation of Nuclei in the Impregnation of Fungi.t—Herr W.
Chmielewskij has been able, by the use of clearing-reagents, to make the
zygotes of Basidiobolus ranarum transparent during the process of
impregnation. After two weeks he finds the nuclei still distinct; but
after four weeks they had completely coalesced. The coalescence of the
nuclei is therefore an extremely slow process; and even after this is
completed, the zygote has apparently to go through a period of rest
before it can germinate. Unripe zygotes, in which the nuclei are still
distinct, will germinate, and there are then two nuclei in the germi-
nating filament.

In Cystopus candidus the oogone contains, before impregnation, only
a single nucleus, and that of the antherid is the same size as that of the
oogone. After the entrance of the male gonoplasm into the oogone, two
nuclei could still be distinguished; but these gradually coalesce, and
the mature oosperm always contains only one.

Saccharine matters of Fungi.t—M. E. Bourquelot has investigated
the composition of the saccharine substances found in Boletus aurantiacus,
and in several species of Lactarius. He finds the results differ according
to the mode of extraction, whether by drying, boiling, or distillation,
from which he infers that when fungi are simply dried, the vital
processes and consequent chemical changes go on for a considerable
period after they are gathered. The results also differ from year to
year in the same species, probably in consequence of varying atmospheric
conditions. When dried at 100°C., the author found in the various
species of Lactarius & proportion of mannite, varying between 2°14 and
15-0 per cent.; while the extract with boiling water yielded a certain
amount of trehalose, which is probably entirely consumed in the process
of drying or ripening.

* ¢ Volvox globator, as the cause of the fishy taste and odour of the Hemlock
Lake Water in 1888,’ 10 pp. and 2 pls., Rochester, N.Y., 1889.

+ Arb. Neu-russ. Naturf. Gesell., xiii. (1888) pp. 113-21. See Bot. Centralbl.,
XXXvili, (1889) p. 789. {~ Comptes Rendus, eviii. (1889) pp. 568-70.

678 SUMMARY OF CURRENT RESEARCHES RELATING TO

Mycorhiza-forming Fungi.*—Herr F'. Noack finds the stratum of
humus beneath the peridium of Geaster fimbriatus, which is abundant
in pine-woods, to be penetrated by coral-like rootlets of Abies eacelsa or
Pinus sylvestris, and these to be invested and permeated by a true
mycorhiza springing from the Geaster, the filaments of which vary in
thickness between 0°3 and 9°0 yp. The following is the history of
development of the mycorhiza.

The exceedingly fine hyaline unseptated hyphe of the mycele unite
into thick bundles coloured white by concretions of calcium oxalate,
resembling in these respects the structure of young peridia. The
hyphe increase in diameter, and become septated, loop-cells being at
the same time also formed, and they gradually become covered with a
dense clothing of papille. When the rootlet of a conifer penetrates
into this mycele, it becomes entirely enveloped by a felt of hyphe,
forming a pseudo-parenchymatous cap over the tip of the root. The
root-cap and the root-hairs of the root then nearly or entirely
disappear, and it branches into the well-known coral-like form. Geaster
fornicatus forms a similar mycorhiza, but not G. striatus.

The mycele of the following fungi has been observed by Herr Noack
to form mycorhiza :—Agaricus (Tricholoma) Russula on beech; A. (T.)
terreus on pine and beech; Lactarius piperatus on beech and on Quercus
pedunculata ; L. vellereus on beech; Cortinarius callisteus on pine; C.
czrulescens on be:ch; C. fulmineus on oak. Experiments on species of
Lycoperdon, Scleroderma, and Amanita all produced negative results.

Structure of Saprolegniacee.t—Prof. M. Hartog has carefully

examined the structure of the Saprolegniacez in the cases of Saproleqnia
Thureti, torulosa, and corcagiensis n.sp., Leptomitus lacteus, and Achlya
prolifera and recurva. He finds the nucleus to be always vesicular, con-
taining a large central mass of nuclein surrounded by a less refringent
layer of hyaloplasm. The nucleus is usually situated in the parietal
layer of protoplasm, but may also be found in the strands which traverse
the cavity in the larger filaments. The protoplasm contains proteina-
ceous particles or microsomes. The apex of the filament, whether
vegetative or re;roductive, contains no nucleus, but a homogeneous
hyaloplasm without vacuoles or microsomes. ‘The nuclei divide by
constriction. but the phenomena of karyokinesis may also be observed.
The formation of zoospores is not preceded by division of the nucleus,

_ but consists essentially of a segregation of the apocytal protoplasm into
distinct cells. ‘The so-called vacuoles in the young oogone are rather
nuclei in every stage of conjugation. Achlya prolifera and recurva are
truly parthogenetic, the “ spermamcebe” of Pringsheim being in reality
parasitic organisms,

Germination of Teleutospores.{— Dr. P. Dietel enumerates the
species of Uredinez, the teleutospores of which germinate on the living
host-plant immediately after maturing, and which can therefore produce
several teleutospore-generations in succession in the course of one year.
Exclusively of the subgenera Leptopuccinia, Lepturomyces, and Lepto-
chrysomyxa, of Puccinia, Uromyces, and Chrysomyxa respectively, only
one other species is known, viz. Hamaspora Ellisii. The author sums

* Bot. Ztg., xlvii. (1889) pp. 389-97 (1 pl.).
+ Comptes Rendus, eviii. (1889) pp. 687-9.
¢ Bot. Centralbl., xxxviii. (1889) pp. 577-81, 609-12, 657-60.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 679

up his observations with the conclusion that the production of lepto-
forms of Puccinia and other genera of Uredinee has no connection with
either the systematic position or the anatomical characteristics of the
host-plant ; it appears rather to depend on climatal conditions.

Tuberacee and Elaphomycstes.*—Dr. R. Hesse makes the re-
markuble statement that the Tuberacee and Elaphomycetes should be
placed, if among fungi at all, on the extreme limits of the Mycetozoa.
In all of them the structure which is known as the receptacle or fructifi-
cation owes its origin to swarm-cells, which possess the capacity, under
certain conditions, of associating themselves into compound bodies,
varying greatly in form, size, and colour, but which normally go through
certain regular stages of development, and finally, after a variety of
changes in furm, combine into the characteristic fructifications of the
Tuberacee and of Hlaphomyces. That which has hitherto been regarded
as the close of the development of these fungi, their process of deliques-
cence or decay, is in reality the commencement of the true period of
reproduction. The small masses of swarm-cells into which these bodies
break up resemble quartz-grains in appearance, but are as soft as wax.
They are formed especially from the dissolution of the glebe and of
warts and scales, and are found in enormous quantities in the humus of
the soil, wherever these fungi are decaying.

The author’s observations were made on Tuber maculatum and exca-
vatum, Balsamia fragiformis, and a number of other Tuberaceze and
Elaphomycetes ; aud he believes these observations to hold good with
regard to the Hymenogastree generally and the typical Lycoperdacee,
such as Lycoperdon, Bovista, Geaster, Polysaccum, aud Scleroderma ;
and also that the warts on the receptacle of the Hymenomycetes may
have a much more important signification than has been generally
ascribed to them.

The author disputes the parasitic nature which has been assigned to
the true Tuberacex, believing them all to be true saprophytes, while
Elaphomyces may partake of both characters.

Synthesis of Lichens.t—M. G. Bonnier records the results of a
series of experiments on the synthesis of lichens, in which care was
taken to avoid previous errors by using only perfectly pure spores of
Algze previously determined, and by preventing the access of other
spores. ‘The mode of culture was in Pasteur-flasks or in cells specially
prepared, and the substratum employed was pieces of rock or bark free
from other organisms and sterilized at a temperature of 115°C. Still
the results were sometimes negative, or foreign organisms resulted from
the access of air at the moment of sowing. In others lichens were
obtained by synthesis corresponding in every respect to those the spores
of which were sown.

The Algz employed were Pleurococcus vulgaris, Protococcus botryoides,
P. viridis, Trentepohlia umbrina (?), T. abietina, T. aurea, Stichococcus
bacillaris, and Vaucheria sessilis ; and the lichens obtained by sowing in
conjunction with them the spores of the corresponding species were as
follows :—With Protococcus—Physcia parietina, P. stellaris, and Parmelia
Acetabulum ; with Pleurococeus — Lecanora ferruginea, L. subfusca,

* Bot. Centralbl., xxxviii. (1889) pp. 518-20, 553-7.
t Ann. Sci. Nat. (Bot.), ix. (1889) pp. 1-34 (5 pls. and 6 figs.)

680 SUMMARY OF CURRENT RESEARCHES RELATING TO

L. sophodes, L. cotilocarpa, and L. cesio-rufa; with Trentepohlia—
Opegrapha vulgata, Graphis elegans, and Verrucaria muralis,

The development of Physcia parietina is described as follows :—
Two spores only were sown, with about thirty Protococcus-cells. The
germinating filament from the spore elongates at its extremity; the
terminal portion swells, often becomes cut oif by a septum, and puts out
lateral swellings which develope into slender branches; these envelope
the alge, until the latter are completely surrounded by hyphe of three
kinds, viz. swollen filaments, clamp-filaments in immediate contact with
the algw, and elongated filaments which extend towards the periphery
apparently in order to search for fresh alg ; the swollen hyphe are the
origin of the pseudo-parenchyme of the lichen.

It is frequently asserted that a constant and essential difference
exists between fungi and lichens in the much greater thickness of the
cell-walls of the latter; but M. Bonnier has watched the gradual
thickening of the walls as the hyphe of the lichen come in contact with
the nourishing alge; it is not strongly manifested until the pseudo-
parenchyme is already partly formed.

Development of Lichens on the Protoneme of Mosses.*—M. G.
Bonnier has observed that when the spores of lichens germinate in con-
tiguity with the protoneme of a moss, they may completely invest it and
carry on a parasitic existence upon it. He has succeeded in obtaining a
parasitism of this kind by inducing the spores of Parmelia aipolia and
physodes to germinate on the protoneme of such mosses as Hypnum
cupressiforme, Barbula muralis, Funaria hygrometrica, Mniwm hornum,
Dicranella varia, and Phascum cuspidatum. The lichen-byphe will in
such circumstances completely envelope the protoneme and ultimately
destroy it, but without producing any fructification. But the protoneme
will sometimes produce buds or propagules with very thick cell-walls
which offer a resistance to the attacks of the lichen-filaments and preserve
the life of the moss. This occurs specially with Mnium hornum. The
lichen-spores will also sometimes germinate on the leaves of the moss,
but will not develope into a perfect lichen unless they meet with algal
gonids.

Pilophorus.t—Prof. T. M. Fries unites together the three species
of this genus of lichens previously known, viz. P. robustus, acicularis,
and cereolus, and describes a new species from Vancouver’s Island,
P. clavatus, distinguished by the very unusual form of the apotheces,
which are no less than four or five times higher than broad.

Fungus-parasites of the Alder.t—Prof. R. Sadebeck states that the
grey spots on the leaves of Alnus incana are produced by Exoascus
epiphyllus—identical with Taphrina borealis—which also settles on leaves
of A. glutinosa already attacked by E. alnitorquus, producing its asci
among those of the latter. The scales of the female catkins of both
species of alder are subject to the attacks of an undescribed Haoascus,
which the author proposes to call H. amentorwm, resembling Ascomyces
endogenus, but marked as belonging to Eoascus by its abundant
mycele.

* Rey. Gén. de Bot. (Bonnier), i. (1889) pp. 165-9 (1 pl.).
+ Naturvetensk, Studentsillsk. Upsala, March 27, 1888 (1 fig.). See Bot.
Centralbl., xxxviii. (1889) p. 764. t Ber. Gesell. Bot. Hamburg, 1888, p. 90.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 681

Rhizoctonia.*—Herr E. Hidam and Herr E. Rostrup f have studied
the mode of parasitism on the beet of the destructive fungus Rhizoctonia
Betz. On the roots of the clover, carrot, and beech are frequently found
little balls, at first red, afterwards blackish, which become transformed
in the spring into pycnids. Rostrup suggests that Rhizoctonia is in fact
the mycele of fungi belonging to the Ascomycetes.

Parasitic Fungus on the Lombardy Poplar.t—M. P. Vuillemin
describes a destructive disease of the Lombardy poplar as being caused
by the attacks of Didymosphzria populina, which in the summer assumes
its pycnidial form of Phoma.

M. E. Prillieux§ confirms this observation, and further identifies
the parasite with one which attacks the leaves of the aspen in the
conidial state, and which is then known as Fusicladium or Napicladium
Tremule. This fructifies in the summer as a Phoma, in the winter as a
Didymospheeria.

Entophytes in Myriopods.||—Prof. E. G. Balbiani describes three
new species of entophytes found in the alimentary canal of the myriopod
Crypteps. One of these, which appears to have been observed by Plateau,
he calls Omphalocystis Plateaui. It occurs in the cesophagus of Cryptops
punctatus and C. hortensis ; moniliform filaments are attached by a basilar
cell to the cuticle; and the parasite grows by budding from the said
basilar cell by acrogenous or intercalary growth in the filaments, and
by lateral budding on the same. Balbiani regards it as a special type
of fungi. The second form, also from the cesophagus, he names Mono-
nema moniliforme ; it has simple moniliform filaments, without a basilar
cell, without ramification, and is less frequent than the former species.
A third form, Khabdomyces Lobjoyi, was also found in the cesophagus, but
only in Cryptops hortensis. It consists of isolated cylindrical rods, and
is referable to the Blastomycetes. The conids are nucleated, multiply by
gemmation, and occur in the walls of the cesophagus, without spreading
to other parts of the body. The author also observed in the same hosts
what he believes to be a new Gregarine, perhaps the Dactylophorus noted
by Schneider, and he noticed, furthermore, a Coccidian in the mid-gut.

Heliotropism of Phycomyces.{—M. J. Massart has establishsd a
curious fact in connection with Phycomyces nitens. He found that this
fungus, when submitted to the opposite actions of illuminations of the
same nature, but of unequal intensity, always bent towards the stronger,
thus verifying the psycho-physical law of Weber for heliotropism.

Puccinia vexans.**—Herr P. Dietel records the existence in this
species of two kinds of teleutospore and two kinds of uredospore. The
teleutospores are either unicellular or bicellular. In addition to the
ordinary uredospores, there are others which resemble teleutospores, not
only in their appearance, but also in the fact that they will apparently
germinate only after hibernating; the author proposes for these the
term mesospere.

* Jahrb. Schles.. Vaterl. Cultur, 1888. See Bonnier’s Rev. Gén. de Bot., i.
(1889) p. 156.
t+ Overs. K. Dansk. Vidensk. Forhand]., 1888. See Op. cit., p. 156.
{~ Comptes Rendus, eviii. (1889) pp, 632-5. § T.c., pp. 1133-5.
|| Journ. Anat. et Physiol. (Robin), xxv. (1889) pp. 5-45 (2 pls.).
§| Bull. Acad. Roy. Sci. Belgique, xvi. (1888) pp. 550-2.
** Hedwigia, xxviii. (1889) pp. 177-9.
1889. 3B

>

682 SUMMARY OF CURRENT RESEARCHES RELATING TO

Saprophytic development of parasitic Fungi.*—Herr B. Meyer
finds that the following fungi, which are normally parasitic on living
plants, can be induced to develope as saprophytes, though they do not
then always develope their organs of propagation :—Polystigma rubrum,
Ramularia asperifolia, Claviceps purpurea, and Protomyces macrosporus,
the last only imperfectly and with difficulty.

Haplobasidion, a new genus of Dematiee.—tIn the fifth fascicle
of his ‘ Fungi parasitici Scandinavici exsiccati’ Herr J. Eriksson gives
the following diagnosis of this new genus :—Hyphee fertiles e mycelio
endophyllo assurgentes, breves, simplices, basidioidex, apicem versus
incrassate, ibique (8—) 4 ramis conidiigeris coronatz, demum replicate,
deciduisque conidiis cicatricose. Conidia globosa, fuliginea, levia. It
is most nearly allied to Stachybotrys, Periconia, and Cephalotrichum.
H. Thalictri grows on Thalictrum flavum.

Lactarius piperatus.|—MM. R. Chodat and P. Chuit describe the
anatomical structure and chemical properties of Lactarius piperatus
Scop. It is of a dull whitish yellow colour, the lamelle being slightly
deeper. The fungus is compact and hard, and the fracture irregular but
not fibrous. The authors succeeded in obtaining from the fungus a
substance with a very biting taste, to which they have given the name
of piperone. It is soluble in alcohol, ether, and chloroform, and becomes
fluid at 100°. L. piperatus ought not then to be eaten without bein
prepared in a manner that will cause it to lose its acridity. ;

Mycetozoa.

Myxomycetes of Denmark.{—Herr C. Raunkizr proposes the
following classification of the Myxomycetes :—
A. Without capillitium.
I. HomopERMEZ.
Liceaceze (Tubulina, Lindbladia).
II. HetERopERMEz.
Clathroptychace (Hnteridium, Clathroptychium).
Cribrariaceze (Cribraria, Dictydium).
B. With capillitium.
Ill. Ca.onemez.
Arcyriacesee (Perichena, Lachnobolus, Arcyria, Cornuvia, —
Lycogala).
Trichiaceee (Hemiarcyria, Trichia).
IV. STeRrEoNEME.
Physaraceze (Badhamia, Physarum, Tilmadoche, Fuligo,
Léocarpus, Craterium).
Didymiacezee (Chondricderma, Lepidoderma, Didymium,
Spumaria).
Stemonitacezee (Lamproderma, Enerthenema, Ancyrophorus,
Comatricha, Stemonitis, Brefeldia, Reticularia).

The Danish species, 96 in number, are described in detail, and a

* Landwirthsch, Jahrb., 1888, 35 pp. and 4 pls. See Bot. Centralbl., xxxviii.
(1889) p. 827.

+ Arch. Sci. Phys. et Nat., xxi. (1889) pp. 385-403 (1 pl.).

+ Bot. Tidskr., xvii. (1888) 88 pp. and 4 pls. See Bot. Centralbl., xxxvyiii.
(1889) p. 676.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 683

large number of them figured. Seven new species are described, and
one new genus, viz. :—

Ancyrophorus. Sporocysts stalked; the stalk is prolonged into
a columel which reaches to the apex of the sporocyst, and there
broadens into a circular disc coalescent with the peridium, the capilli-
tium-threads proceeding from the under side of this disc, and from the
upper half of the true columel; these threads branch dichotomously
towards the apex; the outermost bend outwards, and are covered with
numerous subulate points.

New Myxomycetes.*—Herr M. Raciborski describes the followinz
new species of Myxomycetes from the neighbourhood of Cracow, Poland:
—Lamproderma Staszycii, L. tatricum, Chondrioderma exiguum, Hetero-
dictyon Bieniaszii, Arcyrella cornuvioides, Pericheena Krupiti.

Protophyta.

a. Schizophycee.

Cyclophora.j—This genus of diatoms (Tabellariem), formed by
Count Abbé F. Castracane in 1872, he now proposes to sink altogether in
Diatoma, regarding his C. tenuis simply as a variety of D. hyalinum.
The character on which he relied for the formation of the genus, the
peculiar small circle on each valve, he now finds to have not even a
specific value, since it has been observed by himself or others on several
species of Cocconeis, as well as in Amphora and Nawicula.

Diatoms of African Tripoli.t—Count Abbé F. Castracane describes
the constitution of a tripoli from the elevated valley of Dopi, in North
Africa. He finds twenty-four species of diatoms, all referable to existing
types, except one new one, Cymbella Assabensis. Among them is the
very rare Hpithemia clavata, which has been found also in Lake Nyanza.

B. Schizomycetes.

Number of Bacteria in the Contents of the Gastro-enteric Tube of
some Animals.§—Prof. de Giaxa finds that in eight out of ten herbivorous
animals there is an increase, which is generally considerable, in the
number of bacterian colonies which are developed in a decigramme of
the contents of the small intestine, compared with the number found in
an equal part of the contents of the stomach. In the large intestine
there is always a very considerable increase in the number of micro-
organisms as compared with the stomach, and generally an increase as
compared with the small intestine.

Among ten omnivorous and carnivorous animals, only one was found
to exhibit a slight increase in the small intestine as compared with the
stomach; in the other there was always a diminution, and that was
generally considerable. In these therefore, in opposition to the herbivora,
the small intestine is not a medium which is very favourable for the
reproduction of bacteria. In all cases the greatest reproduction of
microbes is effected in the large intestine, as may be proved by the
quantities found in the rectum.

* Hedwigia, xxviii. (1889) pp. 115-24.

t Atti Accad. Pontif. Nuovi Lincei, xlii. (1889) 9 pp.
{rc Sopp:

§ Arch. Ital. Biol., xi. (1889) pp. 229-36.

684 SUMMARY OF CURRENT RESEARCHES RELATING TO

New Pyogenetic Bacillus.*—MM. Rietsch and du Bourguet describe
a bacillus observed by the latter in the affection called the ulcer of Yemen
at Beyrout. The bacillus varies a good deal in length, and its width is
by no means constant; its mean length is 1°5 pw, and it is ordinarily
twice as long as wide; sometimes it is so short as to look almost like a
coccus. In gelatin it forms colonies under the form of yellowish spots,
which soon become mammillated in appearance, and rapidly liquefy their
medium. When inoculated hypodermically its action is almost nil on
pigeons, fowls, and white mice ; it produced, in two guinea-pigs, tumours
which were absorbed after a few days. The rabbit is more sensitive,
and in the pus produced in it the bacillus was found; this gave pure
cultures in gelatin. <A rabbit killed by it had a large number of the
bacilli in the peritoneal fluid, the heart, the liver, and particularly the
lung.

New Species of Chromogenous Microbe.|—Mr. G. F. Dowdeswell
describes under the name of Bacterium rosaceum metalloides a new microbe
which forms a remarkable pigment altogether similar to magenta-red. It
developes best in solid cultures; and when in full vital activity it
varies from 6-8 » in breadth, and is about twice as long as wide, but
may be large~, so that it presents considerable variations, in this respect.
In this stage it is invariably immobile, and developes rapidly by repeated
transverse divisions, but never forms chain, or zooglaée of any kind.
When it passes into a quiescent stage it forms densely aggregated
masses of cells. After a few days it may exhibit the metallic brightness
which distinguishes it, and after a month or six weeks it ceases to grow.
It developes most vigorously and gives the most richly coloured colonies
when inoculated on slices of boiled potato. In certain liquids it gives
rise to the formation of gas, and if cultivated in a confined space produces
a disagreeable odour. As it cannot resist any elevation in tempera-
ture, it cannot have any direct pathogenetic action on warm-blooded
animals. It is probably a saprophyte on vegetable materials.

* Comptes Rendus, evili. (1889) pp, 1273-4.
t+ Ann. de Micrographie, ii. (1889) pp. 310-22.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 685

MICROSCOPY.

a. Instruments, Accessories, &c.*
(1) Stands.

Binocular Microscopes (Ahrens, Goltzsch, and Holmes).—It is no
doubt somewhat rash to attempt to assert that we have reached a
final point with regard to any branch of microscopy, but at the
same time we are inclined to think that when this notice has been
published, all the forms of Binocular Microscope will have been de-
scribed that it can be at all worth any one’s while to invent—at any rate,
for any purpose of practical use. The only forms which have hitherto
stood the test of use, are those of Nachet, Wenham, and Stephenson.

Ahrens’s Polarizing Binocular Microscope.—Hitherto there has been
some difficulty, Mr. C. D. Ahrens considers, in using binocular Micro-
scopes with polarizing apparatus, mainly on account of the practical
difficulties attending the use of analysing prisms with the double tube
for the two eyes. “My invention has for its object the construction of
binocular Microscopes in which the difficulty of analysing the light is
obviated by ewploying actual polarizing surfaces r
to divide the rays as they emerge from the object- ae
glass. This I prefer to accomplish in the follow-
~ ing manner:—Over the object-glass is set a prism
of black glass having * horizontal side upwards as
close to the object-glass as is convenient, and having
its two faces symmetrically inclined to the axis of /
the object-glass at angles of about 57°, which is
approximately the angle of complete polarization.
The bundle of rays is thus reflected at the proper
angle, and divided at the same time into two parts.
These parts or fays, passing obliquely right and
left, are then reflected up the two tubes to the two
eye-pieces, either by two total reflection prisms or
by polished metal surfaces. Light polarized by a
suitable polarizer before traversing the object, will
be analysed by the said prism or prisms placed
above the object-glass.” The prisms are shown in
fig. 74.

Golizsch’s second Binocular Microscope. — We
have already described { Herr H. Goltzsch’s first binocular Microscope,
one of the features of which was the use of small telescopes for eye-
pieces. He subsequently announced an improvement, by which the
inconvenient vertical stage is dispensed with.

Close above the objective a rectangular prism is placed, the anterior
acute angle of which is in the axis while the hypothenuse surface is
inclined at an angle of 35°, so that half the pencil from the objective is
diverted, to the extent of 7° from the axis, by total reflection. Behind the

* This subdivision contains (1) Stands; (2) Eye-pieces and Objectives; (3) Iu-
minating and other Apparatus; (4) Photomicrography ; (5) Microscopical Optics
and Manipulation ; (6) Miscellaneous.

+ Carl’s Rep. f. Exper.-Physik, xviii. (1882) pp. 27-32 (1 fig.).

¢ See this Journal, 1882, p. 95.

686 SUMMARY OF CURRENT RESEARCHES RELATING TO

first prism is a second one, rather larger, but of similar form, the anterior
acute angle of which projects slightly over the axis. This prism also
diverts the other half of the rays to 7° from theaxis. The pencils diverge
upwards at an angle of 14° and at about 8 inches above the apex of the
angle they are separated from each other by approximately the medium
distance of the eyes apart. The telescopes which replace the eye-pieces
have achromatic object-glasses and the usual double eye-lenses, and by
means of rackwork can be moved so far on their axes as may be requisite
for a decrease in the width of the eyes. The prisms are inclosed in a
box, which, like the tube of an ordinary Microscope, can be raised or
lowered by rackwork or a micrometer-screw. The size of the lower
prism must be regulated according to the largest objective-lenses em-
ployed ; the other may be somewhat (or even considerably) larger; this
is advantageous in that a longer path of the rays in the glass moves the
apex of the diverging axes lower down, and thus aids in limiting the
height of the whole instrument. An aperture on. the upper side of the
box, central with the principal axis, allows of the insertion of a tube
with a small opening, or an ordinary eye-piece, by means of which an
exact adjustment of the prisms is made, it being necessary that a point
of the object seen through the eye-piece in the centre of the field of
view after the prisms are removed should also be in the
Fig. 75. centre of the telescopic field when the prisms are used.
The question of illumination is an important point.
The plane-mirror is never sufficient alone for any kind
of binocular Microscope. The concave can be employed
if it is movable freely in the axis without lateral move-
ment. Still better is a plane-mirror in conjunction with
a movable convex lens, which can be removed from the
stage to double its focal distance. This mode of illumi-
nation is, however, very disadvantageous for the produc-
tion of sharp images; the light is often far too dazzling,
i ie and small diaphragms are consequently necessary.
BY ue With the Stereo-Microscope these should never have the
ale apertures round, but in the form of slits, placed at right
angles to the edges of the prisms; seven or eight of
these (from the narrowest to about 2 mm.) may be
arranged radially upon an ordinary wheel of diaphragms.
The plano-convex illuminating lens shown in fig. 75,
used with a plane mirror, is, however, a much more
suitable arrangement. Upon the plane surface of this
lens two prisms are so placed that their thicker sides
unite in the central line, this being parallel with the
edges of the prisms. Such a lens forms two separate
images of the illuminator ; the two sets of rays intersect
at a point a little above the lens, where the object is
to be placed. Both fields of view are in this way equally
illuminated with diffused light without showing an image
of the illuminator itself. The lens has a radius of curvature of 32 mm.
and a diameter of 40 mm., and the angle of the prisms is 84°; for the
movement of the lens in the axis a space equal to twice the radius of
curvature is sufficient. It can also be made in a quadrangular oblong
form instead of round; in this case a central piece half as wide as long
is sufficient; the light has then freer access to the mirror.

|

PLANE

;
MIRROR\

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 687

The author adds some remarks as to the special objectives necessary
for a Microscope with telescopic eye-pieces. It must not be expected,
he says, that proper images can be obtained with objectives which are
suitable for ordinary Microscopes; for not only does the bisecting of
the rays influence the quality of the images, but the course of the rays is
quite different. We must have, therefore, objectives specially corrected
for parallel pencils. The lenses of an ordinary objective are placed
closer together, as though to suit very thick cover-glass. The object
is of course at the focus of the objective instead of being outside it, as
in the ordinary compound Microscope, or within it, as in the simple.
The results already obtained justify, it is said, the hope that the mode-
rate magnifying powers hitherto reached (scarcely above 200) can be
considerably increased. With a power of 120 the striz on the scales of
Hipparchia Janira were well seen, with an eye-piece power equal only
to the weakest now used; with stronger eye-pieces the power could
easily be doubled.

Fic. 76. Fic. 77.

Holmes’s Isophotal Binocular Microscope.—This is shown in fig. 76.
The optical principle of the instrument was described at p. 870 of
Vol. III. (1880). A peculiarity of the mechanical arrangement is that
the tubes are made to rock from side to side on a socket. The object

688 SUMMARY OF CURRENT RESEARCHES RELATING TO

of this is to enable one of the tubes to be brought in a line with the
optic axis, when the Microscope is to be used as a monocular. The
tubes are clamped in any given position (whether for monocular or
binocular use) by a screw working in the short vertical piece shown
behind them. The screw at the top of the standard acts on the stage
and forms the only adjustment for focus. The isophotal prism slides
inside the crossbar and is pushed forward over the objective, or with-
drawn again when not required to be used, by the screw at the back of
the bar.

There is a second body-tube also of peculiar construction (fig. 77)
which has three tubes. The two outer ones are for use with the bino-
cular prisms, while the central one serves for monocular observation.

Blix’s Microscopes for measuring the radii of the curved surfaces
of the eye.*—Dr. M. Blix uses two compound Microscopes for
measuring the radii of the curved surfaces of the eye. Hitherto the
surfaces have been considered as mirrors, in which, the smaller the
image of any object, the smaller are the radii. The principle which
Dr. Blix makes use of is the following :—

The image of a point in the axis of a spherical mirror, lies in the
axis at a distance from the reflecting surface, which is determined by the
distance of the luminous point from the mirror, and by the radius of the
latter. Ifa compound Microscope, which transmits a ray of light from
a point in the centre of the plane of the eye-piece to the objective, be
placed in the direction of the normal to the reflecting surface and
then adjusted so that the point of intersection of the normal with
the reflecting surface—the principal point—is focused, then the image
of the illuminating point will be at the same place as the point itself.
If the centre of curvature of the reflecting surface is then focused the
image will again coincide, but this will not take place in any inter-
mediate position. If the displacement of the Microscope along its
axis in the two cases is measured it will enable the radius of curvature
of the mirror to be determined by calculation.

This result, however, is not so easily obtained in practice, as the
field of view is too strongly illuminated by the light reflected from the
surfaces of the objective-lenses. Two Microscopes are therefore em-
ployed by Dr. Blix, one to transmit the light and the other to observe
its image. The axes of these two Microscopes intersect each other, so
that the angle between them is bisected by the normal to the reflecting
surface; they can be moved towards the reflector in such a manner that
the point of intersection of their axes coincides with that of the normal
and the reflector. The object (e.g. a diaphragm with a punctured cross
brightly illuminated) in the field of the first tube, is by the shifting of
the tube so adjusted that the image projected by the Microscope falls on
the reflecting surface. By moving the second tube along its axis, the
image of the cross is brought into its field also. If the Microscopes
are now moved together in the direction of their axes, the image of the
cross will disappear from the field of the second Microscope but will re-
appear as soon as the tubes are focused on the plane of the centre of
the reflecting surface. By measuring the extent of movement of the
tubes, the radius of curvature can be obtained.

* Zeitschr. f. Instrumentenk., i. (1881) pp. 381-90 (6 figs.). Cf. also Centr.-Zte.
f. Optik u. Mechanik, iii. (1882) pp. 33-4,

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 689

Figs. 78 and 79 will serve to illustrate the two positions of the
Microscopes T and T,, when adjusted first to the surface of the reflector
AB (H being the “principal point”) and afterwards to its centre C,
o and 0, being the objectives; d the eye-piece of the Microscope, and
d, the diaphragm in the other, and aa, the points in the plane of the
centre of curvature to which the Microscopes are directed in the second
position.

The complete instrument with the two Microscopes is shown in
fig. 80. It is fixed on a cast-iron table T which also supports F, Q, R
for holding the head of the patient in the required position. Hach
Microscope has a tube for the objective 0, and an inner eye-piece-tube

Fic. 78. Fig. 79.

Cc

d and d’. In the right tube the eye-piece is replaced by a small round
plane mirror from the centre of which the silvering is removed in the
form of across. The left tube has a Huyghenian eye-piece, with cross-
threads. Both objectives are of equal power with a focal length of 40
mm. The Microscopes are placed in two short tubes h, attached to
supports ss, which rest on the plate P. In the latter are guides, which
regulate the movements of the tubes, so that they can only move in the
direction of their axes. For displacing the tubes an eccentric movement
is employed consisting of a cylindrical steel axis A, with a radius of
12 mm., protected by a brass sheath H attached to the stand, so that
it lies horizontal and immediately under the plate P, at right angles
with the vertical plane bisecting the angle between the tubes. At the
sides, semi-cylindrical portions / 1, are removed, in order to give room
for the lowering of the triangular pieces ¢¢, connected with the tubes.
From the apices of these pieces is cut a slit at right angles to their base
in which slides (pressed with a spring) a cylindrical steel rod +, 4 mm.
thick, which lies within the periphery of A, parallel to it and at a dis-
tance of 10 mm. This distance can be regulated by four screws ¢, ¢y C3 ¢,.
If the axis is revolved on its centre by the handle X, the rod will

690 SUMMARY OF CURRENT RESEARCHES RELATING TO

describe a curve, and sliding in the two slits, will move the triangular
pieces and with them the tubes forward in a horizontal plane.

An index z (with a vernier) on the axis A serves to measure the
angle made by the revolution of the axis, on a scale graduated from the

Fic. 80.

central point of the are to 90° in either direction, whence the length of
the radius can be calculated by appropriate formule given by the
author.

If however what is required is to determine the distance between the
principal points of two reflecting surfaces on the same axis—for instance,
to measure the thickness of the cornea—an arrangement is necessary by
which the point of convergence can be moved from the principal point
in the one surface to that in the other, the common axis of the two sur-
faces bisecting the angle between the tubes. The latter must therefore
be capable of being moved parallel with this axis without changing their
relative position. For this the same eccentric mechanism is used as
described above. The plate P is not fixed immovably to H, but a thin

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 691

plate b soldered to the latter, is inserted between them and on this the
plate P moves (see fig. 81); screws f and f, fix P to b, and by means of
two other screws the tubes and P can be firmly united. H is attached to
the column B which can be lengthened, thus raising the plane of the
tubes. The plate D is connected with the table T in a special manner
(movable by the hand or by screws) which needs no particular descrip-
tion here—the mechanism is shown at g, i, k, m, m,, n, q, v, and w.

Fig. 81.

In a later form Dr. Blix has simplified the instrument, principally
by the omission of the cylindrical axis A and the parts in connection
with it.

Andrew Ross’s Screw and Pinion Coarse- and Fine-Adjustment.—
Amongst an accumulation of pieces of experimental mechanism devised
in connection with the Microscope at various times during the past sixty
years, we recently found one of the earliest fine-adjustments designed
by the late Andrew Ross, which is shown in figs. 82 and 83, and which
comprises a coarse- and fine-adjustment in one piece of mechanism.

In place of an ordinary rack for the coarse-adjustment there is a long
screw the thread of which serves as a rack. The screw is sunk in a
groove cut vertically in the back of the stem F supporting the cross-arm
and body-tube, leaving about one-third of its transverse section to be
acted upon by the pinion D (and milled head E) for the coarse-adjust-
ment. The upper end of the screw passes through the cross-arm B,
and a milled head A is applied on the top by which it can be turned, the
screw-thread then engaging the teeth of the pinion after the manner of
a tangent-screw, so that the screw, together with the stem and body-tube,
travels slowly up or down, forming a fine-adjustment.

692 SUMMARY OF CURRENT RESEARCHES RELATING TO

We found the mechanism as left by Andrew Ross, and it has since
been applied to a stand by Mr. Anderson, who informs us that he
assisted in the original construction about fifty years ago.

Fie. 82. Fie. 83.

M‘Intosh’s Microscope-Attachment.*-—Dr. L. D. M‘Intosh devised
this apparatus for use with solar or artificial light for projecting or
photographing microscopic objects with oblique illumination, or pro-
jecting opaque objects, and before describing it he explains the con-
struction of his solar Microscope and stereopticon combination (fig. 84).
The optical parts can be used with either solar or artificial light, with
only slight changes. To use sunlight, there is a plane mirror M, 12 by
14 in., which turns on a vertical horizontal axis by means of spur-wheel
gears connected with rods R, R. ‘The gears are supported by a bracket,
which is securely clamped to a perpendicular board F. On the front of
this board is an opening to receive the condensing lens, which is
mounted in a brass tube C, with draw-tube. The draw-tube E has a
screw-thread to receive either the microscopic attachment K, for pro-
jecting microscopic objects, or a stereopticon lens for projecting photo-
graphic transparencies. By means of the thumb-wheels V, W, the

* Proc. Amer. Soc. Micr., x. (1888) pp. 155-8 (4 figs.),

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 6938

mirror can be adjusted at any angle desired for illuminating a trans-
parency or microscopic object.

To use the solar Microscope or stereopticon, place it in a window
exposed to direct sunlight, and adjust the mirror so that the light enters

Fic. S84.

A

BAKER- CO

the condensing lens parallel with its axis; adjust Microscope or stereop-
ticon lens; place the object on the stage, or, if a transparency, in front
of the condenser, and a well-defined image is seen on the screen. To
use the optical parts of the instrument just described with artificial

694 SUMMARY OF CURRENT RESEARCHES RELATING TO

light, viz. oxy-hydrogen or electric, remove the brass tube C, containing
the condensing lens and draw-tube, from the mirror attachment and
connect to the combination stereopticon (fig. 85), using either the stereop-
ticon lens or Microscope as desired. The light is centered and adjusted

Fig. 86.

by means of thumb-screws on the oxy-hydrogen jet. The adjustment is
the same as with solar light. The only change (two condensing lenses
are used with artificial light), one of these
Fic. 87. lenses is removed and only one used, and a
small secondary condenser placed under the
stage of the Microscope. With this com-
bination just described we can only project,
with transmitted light, transparent objects.
The attachment, fig. 86, is for photo-
graphing and projecting objects with oblique
illumination, or projecting opaque micro-
scopic objects. It is constructed as fol-
lows:—To the base of the combination
stereopticon is clamped a triangular piece
of brass U, by means of thumb-screws, with
a slot X near its apex, to hold a movable
hollow pillar I. This pillar is slotted on
one side, and has a screw and clamp G to
hold a perpendicular pinion P, which in
tnrn receives the stage and working part of
the stand (fig. 87). This is securely clamped
by means of the screw G, fig. 86. Hx-
tending through from the lower end of the
pillar I is a screw h for raising or lowering
the stage of the Microscope and body-tube.
The body-tube K of the Microscope is in a horizontal position, and the
stage S vertical. These are directly in front of the condensing lens. By

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 695

means of the pinion P in the pillar I, the Microscope can be rotated
horizontally to the right or left. The centre of an object on the stage
corresponds with the centre of motion. By

means of this rotation any angle, either of Fic. 88.

solar or artificial light, can be obtained for

photographing and projecting, also projecting i |

opaque microscopic objects, or projecting with
transmitted light. |
To use the attachment with solar light, the
plate U can be removed from the stereopticon,
and attached by means of a bracket to the
front of the mirror-board (fig. 84, F) of the
solar instrument, adjusted the same as with
artificial light. For photographing micro-
scopic objects a camera-box must be con-
nected with the tube K, the same as is used
with transmitted light to illuminate the ob-
ject.

Old Italian Microscope.—In the Museo
Copernicano, Rome, we noted the Microscope
shown in fig. 88, which is reproduced from
a photograph that we obtained by the courtesy
of the Curator, Dr. A. Wolynski. The origin
is unknown, but it may, we think, be
inferred with some probability to be a
very early form of Microscope from the
fact that it was evidently devised for
viewing opaque objects only. Our con-
jecture is that, from the peculiar design
of the nose-piece, it may have been a very
early modification of a “ Divini” Micro-
scope. The body-tube slides through the
tube-socket, which is supported by orna-
mented tripod scrolls on a raised base;
the whole is of brass. The eye-piece
lenses are held in their cells by a thin
plate of brass notched out, the teeth being merely folded on the edges
of the lenses.

AMATEUR.—Notes on the Microscope-stand and some of its accessories.
[The foot or base—The supporting pillars—The arm—The body.]
The Microscope, 1X. (1889) pp. 264-75.
BrHrens, W., A. Kosseuu, and P. ScHIrFFERDE,CKER.—Die Gewebe des
menschlichen Korpers und ihre mikroskopische Untersuchung. Band I. Das
Mikroskop und die Methoden der mikroskopischen Untersuchung. (The tissues
of the human body and their microscopical examination. Vol. I. The Microscope
and the methods of microscopical research.)
viii. and 315 pp., 198 figs. 8vo, Braunschweig, 1889.
Martuews, C. G., and F. E, Lort.—The Microscope in the Brewery and Malt-
house. xxi. and 198 pp., 30 figs., and 22 pls. S8vo, London and Derby, 1889.
Microscope, The New Acme No. 5 with rack and pinion.
Queen’s Micr, Bulletin, VI. (1889) p. 25 (1 pl.).
Watson & Sons’ Edinburgh Student’s Microscope.
Engl. Mech., XLIX, (1889) p. 471 (3 figs.).
WooumAn, G. §8.—Selecting a Microscope.
Amer. Mon, Micr, Journ., X. (1889) p. 182.

696 SUMMARY OF CURRENT RESEARCHES RELATING TO

(3) Iuminating and other Apparatus.

Taylor’s Oleomargariscope.*—During the prosecution for violation
of the Butter Laws of the District of Columbia, it was found necessary
in jury trials to have a simpler form of microscopic and polariscopic

combination than the cumbrous stand,
Fic. 89. Fic. 90. with polariscope, in general use,
; m5 since each of the parties interested
—judge, jurymen, and attorneys—
A desired to see for themselves the
crystalline forms seen in the fatty
compounds known as oleomargarine.
To this end Dr. J. Taylor contrived
the oleomargariscope, illustrated by

the accompanying figs. 89 and 90.
Fig. 89 represents its general
appearance when not in use. Fig.
90 represents a sectional drawing

2 showing its internal structure.

A, an ordinary eye-piece.

B, a 1/2 in. objective of the
usual constructiou.

a, Nicol’s prism or analyser.

B b, polarizer firmly secured in

tube c, which tube may be rotated
@ as desired, thereby changing the
Z prismatic colours.

d, two discs of thin plate glass,
between which a small portion of
butter or oleomargarine is placed,
ce the discs held in position by ring f.

e, a disc of selenite held in posi-
tion by ring q.

h, a lens for the double purpose of illuminating the polarizer and
protecting it from dust.

A lens is also placed over and above the polarizer b, which concen-
trates the light on the object between the dises d.

It will be seen from the drawing that the objective is readily focused
by means of the draw-tube.

When the object is held up to a strong light, if the butter is pure
and free from adulteration, an even green or red colour only will be
observed, depending upon the character of the selenite used. If “oleo”
or lard is used instead of pure butter, a fine display of prismatic colours
will be observed.

Recent Improvements in Electric Lighting applied to Micrography
and Photomicrography.t—Dr. H. van Heurck describes the Radiguet
battery and electric lamp of Prof. Engelmann, a combination very service-
able for the microscopist, since it affords a bright light whose intensity
is under perfect control, and the cost of maintenance is very trifling.

Each element of the Radiguet battery comprises a stoneware jar, a
carbon cylinder, a porous pot, and an amalgamating support with ite

i]

ul

Dio yao) ee aaa

REESE

* Proc. Amer. Soc. Micr., x. (1888) pp. 159-60 (2 figs.).
+ Bull. Soc. Belg. Miecr., xv. (1889) pp. 24-31 (4 figs.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 697

reservoir. The construction of the latter, in which alone the battery
differs from that of Poggendorf, depends on the fact observed by Radiguet
that when mercury containing traces of zinc is in contact with copper,
the current tends to transport the mercury over the whole surface of the
copper. It consists of a copper tube, coated with zinc, carrying a sort
of basket which holds the zinc in the form of small balls. Beneath the
basket is a porcelain dish which contains the amalgam, and is connected
by a copper rod to the two metal pieces forming the base of the basket.

To start the battery an acid solution of sodium bichromate is poured
into the outer jar and pure water into the porous pot. The liquid in
the latter requires changing
every week, and that in the Fie. 91.
outer jar every month. This
is easily effected, without
dismounting the battery, by
the use of the Radiguet
siphon. The larger arm of
the siphon is connected by
tubing with a caoutchouc
ball, and incloses the nar-
rower tube which forms the
other branch. The lower
extremity of the larger arm
is narrowed, so that when
the ball is gently pressed,
the increase of pressure in
the tube forces the liquid
into the narrow branch and
the siphon functions. By
a strong quick pressure, on
the contrary, the liquid is
driven completely out of
the tube, and the action is
stopped at will.

The EMF of the battery
is about two volts, and the

best arrangement for main- ei <i

taining a steady light for a —<—<—
considerable time is to unite i
for quantity two series of NN
three elements.

The apparatus designed
by Prof. Engelmann (fig. 91) consists of a copper base M carrying the
rheostat Rand lamp. The path of the current is seen from the figure,
connection between rheostat and lamp being made by a rod of copper.
The lamp can be adjusted in height by means of the two copper tubes
S sliding one within the other, and can be brought into any position by
means of the ball-joint. The rheostat consist of a cylinder of copper
insulated from the base by ebonite or serpentine, and containing a pile
of thin discs formed by a mixture of graphite and gelatin. By means
of the screw the discs can be more or less compressed together, and
thus the resistance regulated with great nicety.

An improved form of the apparatus, constructed by wr Kagenaar,

1889. Cc

698 SUMMARY OF CURRENT RESEARCHES RELATING TO

consists of a copper plate, 20 cm. by 10 cm., supporting at one end the
lamp as described above, and on the rest of its length a horizontal com-
plementary rheostat. The latter consists of a long tube of serpentine
inclosing 120 discs of graphite, and gives a range of resistance from
1/4 ohm to 1000 ohms.

Lracu, W.—A substage Condenser for the Microscope.
Trans. Manchester Micr. Soc., 1888, pp. 76-8 (6 figs.).
Mites, J. L. W.—Sub-stage Illumination by simple devices.
Ibid., 1888, pp. 78-80 (1 pl.).
(4) Photomicrography.

“Artistic Photomicrography attained.’*—Dr. W. X. Sudduth
recently gave a lecture on histology before an American Dental Society,
illustrated with the aid of the stereopticon, which is reported as
follows :—

“ He exhibited the results of his experiments in colouring slides in
facsimile of the stained specimens which had been photographed. The
Microscope is undoubtedly valuable in investigating tissues; never-
theless the reported discoveries of microscopists are not always reliable.
Great obstacles arise in the use of the instrument, even after the speci-
men has been mounted, not the least being the fact that focusing is
necessary, and that no two men see exactly alike. Therefore, when A
focuses on a specimen to show a certain peculiarity, which he claims to be
able to discern, he finds it difficult to demonstrate his discovered fact to
B, because B cannot tell when he focuses whether he is viewing the

same plane seen by A. Of course, when examiners are experienced .

microscopists the difficulties are lessened, because the trained eye is
familiar with the appearances of different tissues, and this materially
assists in obtaining the true focus. For example, suppose A claims to
show lacune and canaliculi in a specimen of cementum. B is ac-
quainted with the microscopic appearance of dentine, and in focusing
aims to get the tubuli of the dentine which is adjacent to the cementum
distinctly outlined, and having done so, knows that the cementum also
is in focus, and should be able to see the lacune if present. Again, it
is only the trained eye which is able to distinguish breaks, tears, or
foreign bodies (as shreds of lint, &c.), and the surfaces of the tissues
from the sides or thickness; profile views look flat, not only at the
edges of the specimen, but at all points over the surfaces; shadows
become lines, and resemble special features of tissues. To lessen these
difficulties various methods of staining are resorted to, it being known
that different kinds of tissues are differently acted on by the same agent,
thus producing various tints, and materially aiding in the differentiation
of tissues, which may thus be recognized by their known colours if the
stain used be known. It also shows plainly breaks, tears, and foreign
bodies.

“ Having prepared and mounted a specimen, in order to show what
he sees with his instrument, the investigator may reproduce as accurately
as possible with his pencil the picture in the field of his vision. These
drawings from specimens, however, only carry weight in proportion to
the honesty and ability of the artist. Therefore, as Dr. Sudduth truly
says, drawings mae by photolithographic processes are the more
valuable, being above suspicion of inexactness or perversion through

* Odontographic Journal, x. (1889) pp. 44-8.

‘

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 699

bias. The tissues themselves have been used as lantern slides, but high
lantern power and intensity of light are requisite, and he knows of but
two lanterns capable of such demonstration, one being the Stricker
lantern. ....

“ Having stained a specimen, and thus made distinct the differentia-
tion of tissues, the advantage is again lost in the photomicrograph,
because, of course, the colouring is not reproduced, the picture being
only one of lights and shades, This has been remedied to some extent
by having the lantern-slides painted by hand, and by re-touching, thus
making more prominent the outlines. Some have attained high excel-
lence in this art, but it is open again to the objection of bias. An artist
might colour his slide to prove his theories. Dr. Sudduth has experi-
mented arduously, hoping to find a method by which he could colour
slides by such a process as would dispose of this objection, and enable
him to project on the screen facsimiles of the stained specimens, making
the lantern picture appear as does the specimen itself under the Micro-
scope. His exhibit proved that he has succeeded marvellously well. He
has done this not by hand-work, but by a process of toning in the dark
room. He has been specially successful in reproducing the purple and
pink of hematoxylin and eosin, Bismarck brown and gentian-violet.

“He showed on the screen not only coloured slides, but also some
untinted. Conspicuous among these were beautiful specimens of the
forming blood-corpuscles in the mesoblast of the pig embryo, white
and red corpuscles of human blood, oval corpuscles from the thrush,
similar but larger ones from salmon, oyster-shaped corpuscles from the
frog, and a most beautiful slide showing the enormous corpuscles from
the Amphioma (a species of lizard). As showing comparative analogies
and differences between blood of various species these slides were
specially gratifying... .

“Then began the specimens in colour. A slide showing stellate
reticulum exemplified how well he reproduces the hematoxylin and
eosin stains. Next followed the apex of a tooth, showing Tomes’s fibres
retouched. Several slides were shown of the rete Malpighii coloured
by hand, and also by the Doctor’s method, which latter seemed vastly
more satisfactory and truthful. One of these in Bismarck brown
demonstrated how a single stain may be used, the lights and shadows
being differently affected; for which reason he thinks this particular
stain will prove most valuable. A specimen showing the pigment layer
of the retina in gentian-violet was much admired. A segment from the
mesentery was very clear and distinct. Stained with silver the result
was dark lines against a yellow background. Nuclei show as brown
points. A few slides in gentian-violet were shown, but this we were
told is the most difficult of the colours to manage. A very beautiful
slide was from a macroscopic specimen, stained methyl-green, a section
of the finger showing the soft tissues and the bone, also the forming
nail of a three months’ human foetus. This was shown because it is the
only colour with which he has succeeded in differentiating the nail,
which usually appears so light that it is very indistinct. In this picture
it was quite plainly seen. Some slides followed showing developing
bone, cartilage, &c., and then one of special interest, showing the meso-
blastic tissue forming periosteum and pericementum, which is the first
differentiation into a membrane; these two tissues, which so many claim
to be different, are shown to be similar, being similarly developed.

\ aoe Dag

700 SUMMARY OF CURRENT RESEARCHES RELATING TO

“In the discussion which followed the termination of Dr. Sudduth’s
talk, Dr. Allen admitted that much credit was due to Dr. Sudduth for
his success in colouring slides, but whilst the staining of specimens was
of value as aiding the differentiation of tissues, he, Dr. Allen, could not
see what was gained by colouring slides. Whilst this is undoubtedly
true, the plain photomicrograph being perfectly intelligible to the trained
eye, it was the general opinion among the members present that the
coloured pictures were more satisfactory to those not so well acquainted
with the tissues.”

Photomicrography and the Chromo-copper Light-filter.*—Dr. H.
Zeltnow claims that his light-filter fulfils the two conditions required of
it, namely, it only allows rays clearly visible to the eye and those of a
definite wave-length to pass through, and when used in a concentrated
form wave-lengths of from 570 to 550 only traverse the filter, so that
the light may be fairly called monochromatic. With ordinary objectives
perfectly sharp negatives are obtained. The filter is made by dissolving
160 grm. of pure dry nitrate of copper and 14 grm. of pure chromic acid
in water up to 250 ccm. A solution more easily made and sufficient for
almost all cases in a layer of 1 to 2 cm. thick is composed of 175 grm.
sulphate of copper, 17 grm. bichromate of potash, and 2 cem. sulphuric
acid in water up to 1/2 litre. With a mineral-oil lamp the latter fluid
may be diluted with an equal or double volume of water.

Since ordinary dry plates are but little sensitive to light which has
passed through this filter, erythrosin plates must be used. ‘These are
produced by bathing the former in a weak solution of erythrosin (1 grm.
erythrosin dissolved in 500 ccm. spirit and 5 ccm. of this solution with
200 ccm. of water are used for each bath). These plates will only keep
for three or four weeks at the most, but erythrosin plates can be obtained
from the makers which will last from three to six months. Owing to
the erythrosin the plates are very sensitive to yellow-green rays with a
wave-length of 560.

A fluid very similar in outward appearance to the chromo-copper
filter can be made by the supersaturation of copper salts with ammonia
and dilution with chromate of potash. This, however, only allows such
green rays (510-455) to which the erythrosin plates are little sensitive
to pass through. Preparations stained red, blue, green, blue and violet,
are easily photographed by aid of the chromo-copper filter, since in
consequence of the extinction of these colours the preparations appear
black on a green ground.

Simmons, W. J.—Magnification in Photomicrography.
Amer. Mon. Micr. Journ., X. (1889) p. 180.

(5) Microscopical Optics and Manipulation.

Simple Apparatus for measuring the Magnification of Optical
Instruments.|—The usual method of measuring magnifying power con-
sists in comparing the image of an object of known dimensions, seen by
one eye through the instrument, with another object seen at the same
time by the other eye. By a simple optical arrangement, however, both
can be seen simultaneously by the same eye, which is the principle of
the apparatus constructed by Dr. A. Oberbeck. Two rectangular mirrors

* Eder’s Jahrb. f. Photogr. u. Reproductionstechnik, 1889.
+ Central.-Ztg. f. Opt. u. Mech., x. (1889) pp. 176-7 © figs.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 701

(fig. 92), 25 mm. long and 15 mm. broad, are set in a rectangular frame
at a distance of 6 cm. apart. They are movable about the axes A B and
C D and can be fixed in any required position by means of the screws A
and C. The frame is fastened to a stand adjustable in height, and is
movable about the axis EF. The mirror AB has a portion in the
middle plain. For determining the magnifying power of a Microscope
the frame is set horizontally, and both mirrors are fixed at 45° to the
horizontal with AB directly above the eye-piece, and C D above the
object intended for comparison which lies by the side of the Microscope .
and is seen by double reflection at the same time as the image of the

Fig. 94.

Fic. 92.

object beneath the Microscope. For the latter the author uses a
micrometer scale with lines at distances of 1/10 mm. and 1/100 mm.,
and for the comparison object an isosceles triangle, with base 20 mm.
and height 100 mm., printed on grey paper. It is easy to see how many
micrometer divisions correspond to one of the triangle, thus in fig. 93,
4 mm. divisions fall on the No. 8 division which would correspond to a
magnification of 20 times where the micrometer divisions are tenths.
The proper magnifying power is then this number multiplied by the
ratio of the distance (a + 6) of the object of comparison from the eye to
25 cm. (least distance of distinct vision). (Cf. fig. 94.)

Brapy, N.—Illustrations of Diffraction.

[‘‘ My purpose this evening is to show by actual experiment how even a simply
constructed Microscope may be made a most valuable instrument in ex-
amining the phenomena of this branch of Physical Optics, and to illustrate
how cheaply and how easily many interesting diffraction experiments may
be made.”’}

Paper read before the Western Microscopical Club, March 4th, 1889, 10 pp.
Licuton, W.—Instantaneous Changes of Field.

(Instantaneous changes from dark field to light field and back again with the
largest numerical aperture possible. ]

Amer. Mon. Micr. Journ., X. (1889) p. 164.
NeE.son, E. M.—Diatom Structure.
Trans. Middlesex Nat. Hist. Soc., 1889, 13 pp. and 1 pl. of photomicrographs.

702 SUMMARY OF CURRENT RESEARCHES RELATING TO

Netson, E. M.—On the Formation of Diatom Structure. II.
Journ. Quek, Micr. Club, III. (1889) pp. 308-9 (1 pl.).
en » An instrument for exhibiting the 1/2500 in. without a lens.
Journ. Quek. Micr. Club, TV. (1889) pp. 20-1, 46-7.
Nevuporr, F., Jr.—Charles Fasoldt Sr.’s Rulings.
[Claim to have resolved 220,000 lines to the inch.]
The Microscope, 1X. (1889) pp. 157-9.
Editorial Note, pp. 148-9.
See also St. Louis Med. and Surg. Journ., LVI. (1889) pp. 289-90.
PETTIGREW, J. B.—On the use of the Camera Lucida.
Trans. Manchester Micr. Soc., 1888, pp. 80-3.
Royston-Picott, G. W.—WMicroscopical Advances. XLVII.
[ Apochromatie Hidolic dots and Chromatic Beads. ]
Engl. Mech., XLIX. (1889) p. 315-6 (© figs.).
Suitu, T. F.—On the Abbe Diffraction-plate.
Journ. Quek. Micr. Club, TV. (1889) pp. 5-8.
Tuompson, J. C.—President’s Address to the Liverpool Microscopical Society.

[Deals largely with Prof. Abbe’s theory of the Microscope, “the distinguishing
feature of the microscopical science of the last twenty years.” ]

Journ. Liverpool Micr. Soc., I. (1889) pp. 1-24 (2 figs.).

Warp, R. H.—Micrometry by the Camera Lucida.
Queen's Micr. Bulletin, V1. (1889) p. 24.

Wenuam, F. H.—Large Apertures in Microscopy.

[Characteristic letter in reference to the old aperture controversy. ‘I have
long since turned out or destroyed every paper or journal that contained
matter relating to the subject.” ]

Engl. Mech., XLIX. (1889) pp. 438-9. -

(6) Miscellaneous.

Celebration of the Third Centenary of the Invention of the
Microscope.—The executive committee of the International Exhibi-
tion of Geographical, Commercial, and Industrial Botany, which will be
held at Antwerp in 1890, have decided to celebrate the third centenary
of “one of the most fruitful inventions of which science can boast, that
of the Microscope.”

With this object the committee propose to organize (1) a retrospective
exhibition of the Microscope; (2) an exhibition of the instruments of all
existing makers, of accessory apparatus, and of photomicrography.

A series of lectures, illustrated by the photo-electric Microscope will
be given during the exhibition. They will include (1) the history of the
Microscope; (2) the use of the Microscope; (3) the projection Micro-
scope and photomicrography ; (4) the microscopic structure of plants ;
(5) the microscopic structure of man and animals ; (6) microbes; (7) the
adulteration of alimentary substances, &c., &e.

It is intended to place the exhibition under the patronage of a
“Comité d’honneur,” which will be “composed of persons who have
rendered the greatest services to microscopical science, and who hold
the most honoured rank.”

Cronin Mystery, the Microscope in the. Amer. Mon. Micr. Journ., X. (1889) pp. 187-8.

Dallinger, Rev. W. H., an Interview with—Science and Christianity.
Quiver, 1889, pp. 351-5 © figs.).
Desy, J., Bibliotheca Debyana, being a catalogue of books and abstracts relating
to Natural Science, with special reference to Microscopy, in the Library of.
(Vol. I. 1. Serial and Periodical Publications. 2. The Microscope and its
Technicalities. 3. The Protozoa.) iv. and 151 pp. S8vo, London, 1889.
Fasoldt, Charles—Obituary Notices of. The Microscope, 1X. (1889) pp. 173-4.
Queen’s Micr. Bulletin, V1. (1889) p. 22.
St. Lovis Med. and Surg. Journ., 1889, p. 366.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO, 703

Laboratoires de Micrographie a l’Exposition universelle de 1889. (Microscopical
Laboratories at the Paris Exhibition of 1889.)
Ann. de Micrograplie, II. (1889) pp. 426-8, 483-5, 520-3.
Martin, N. H.—A Plea for the Microscope, being the Annual Address delivered
before the North of England Microscopical Society by the President.
16 pp. 8vo, private circulation, 1889.
Mascart, M. E.—Traite d'Optique. (Treatise on Optics.)

[Microscopes, p. 137.] Vol. I., viii. and 638 pp. (199 figs.). 8vo, Paris, 1889.
PELLETAN, J.—La Micrographie a l’Exposition universelle de 1889. (Microscopy
. at the Universal Exhibition of 1889.)

Journ. de Micrographie, XIII. (1889) pp. 366-9, 403-7, 430-6, 464-7.
» [Distinction between ‘“micrographes”’ and ‘‘ microscopistes.”
‘English and American Microscopy compared with French and German. ]

(“For the one the microscopic object is the subject of study, the Microscope is
the means. . . . For the others the object is only the means, the subject of
study is the Microscope itself.”’]

(“In England and in America the Microscope is not in the same hands as with
us. Whilst in France and in Germany the Microscope is only in the hands
of professional scientists, and amateurs are rare, it is quite the contrary with
the English, where the Microscope is much more common. The world of
amateurs is there extremely numerous, fervent, and, it must be recognized,
generally rich. These devotees of the Microscope form many powerful
societies and clubs, and support numerous microscopical publications, often
luxurious, always prosperous.” ]

Ibid., pp. 225-9, 321-6.
Royston-Pigott, the late Dr.—Obituary Notice.
Journ. of Microscopy, II. (1889) p. 254.
Engl. Mech., L. (1889) pp. 89-90.
ScuortT—veber Glasschmelzerei fiir optische und andere wissenschaftliche Zwecke.
(On glass-melting for optical and other scientific purposes.)

Central-Ztg. f. Opt. u. Mech., X. (1889) pp. 221-38 (1 fig.), 232-4 (1 fig.).
Cf. also Queen’s Micr, Bulletin, VI. (1889) p. 15,
from ‘ Science of Photography
and ‘ Ber. Vereins Férderung Gewerbfl.,’ 1888, p. 162.

Tyson, J. —Ignorance of the Microscope among Physicians.
St. Lowis Med. and Surg. Journ., LVI. (1889) pp. 368-9,
from ‘ Philadelphia Med. News.’

B. Technique.*
(1 Collecting Objects, including Culture Processes.

Culture of Infusoria.,—M. E. Maupas recommends as damp chambers
low flat-bottomed dishes with vertical sides, about 20 cm. in diameter.
The dish is partly filled with fine well-washed sand, and in this are
planted longitudinally two upright strips of glass, of such a height that
the superior edge is 4 or 5 mm. below the level of the edge of the dish.

On these upright pieces as supports are placed three others, the
middle one having a width of 4-5 cm., the two others 2 cm. only. It is
on these three slips that are placed the slides bearing the infusoria. The
whole is covered by a glass plate fitted as hermetically as possible to the
edge of the dish. The dish being filled with rain-water up to the hori-
zontal strips, the air-space is reduced to a layer of 4 or 5 mm. in thick-
ness. This layer of air is always saturated with moisture, and the
preparations suffer only an extremely feeble evaporation.

After each operation with a pipette, it should be washed with care, by
forcing fresh water through it several times. Some infusoria have a
strong adhesive power, and it often happens that they are left adhering

* This subdivision contains (1) Collecting Objects, including Culture Pro-
cesses; (2) Preparing Objects; (3) Cutting, including Imbedding and Microtomes ;
(4) Staining and Injecting; (5) Mounting: ; including: slides, preservative fluids, &c. ;
(6) Miscellaneous. iy Arch, Zool, Exper. et Gén., xvi. (1888) p, 179.

“

704 SUMMARY OF CURRENT RESEARCHES RELATING TO

to the internal surface of the tube; hence the importance of washing
after each experiment.

In order to supply carnivorous species easily with food, it is neces-
sary to find among the more common infusoria a species of small size
that can be readily cultivated. Cryptochilum nigricans answers perfectly
these conditions. Itis herbivorous, and occurs everywhere in abundance.
In order to utilize it as food for carnivorous species proceed as follows:
—Prepare an infusion by cutting up a few pinches of hay in water, and
heat the same for a few minutes to a temperature of 60° C. for the pur-
pose of destroying strange species. Allow the infusion to stand two,
three, or four days, according to temperature, until Schizomycetes have
developed in it, then sow some Cryptochila in it, taking care not to intro-
duce other species at the same time. The vessel containing the infusion
should always be covered by a closely fitted plate of glass. The Crypto-
chila, finding abundance of food in the Schizomycetes, thrive and multiply
by myriads. When the culture begins to decline, as it always will in
regular course, it can be revived two or three times by adding crumbs of
bread in small quantity. Too much bread causes acid fermentation,
which destroys the infusoria. Instead of hay, pepper might be employed
for these infusions, but it would be necessary to determine by experiment
the quantity that could be safely mixed with a given volume of water.
Too large quantities have been found to give infusions that checked the
development of the infusoria.

Having thus obtained a well-stocked infusion, the mode of serving
the Cryptochila to the carnivorous species isolated in the manner above .
described is as follows :—Place a drop of the infusion on a slide, and
cover it with a cover-slip. It will then be seen that the Oryptochila
collect round the edge of the cover, and in this position they are easily
drawn into a pipette, and then delivered over to the carnivorous species.
This mode of feeding enables one to make sure that no foreign species is
introduced into the culture. Other species would undoubtedly serve the
purpose of food as well as Cryptochilum—for example, Colpidium colpoda.

In the culture of herbivorous species, M. Maupas used boiled flour as
food. A pinch of flour is placed in a sufficiently large quantity of rain-
water, and boiled two or three minutes. With this pap one can easily
supply the needs of Paramecium, Colpidium, Glaucoma, Vorticella, and
probably all species that ordinarily feed almost exclusively on Schizo-
mycetes. This food is easily prepared, and is readily served by allowing
it to flow in small quantity under the cover-slip of the preparation. It
keeps only a short time, and hence must be renewed every day or two.*

Foster, R. A.—Investigation of Bacteria by means of Cultivation.
i Amer. Mon. Micr. Journ., X. (1889) pp. 124-6.
Fourrvr, A.—Etude sur la culture des microorganismes anaérobies. (Culture of
anaerobic micro-organisms.) 73 pp., 25 figs. S8vo, Paris, 1889.
Jurrries, J. AW—A new method of making Anaerobic Cultures.
Med. News, 1889, pp. 347-8.

(2) Preparing Objects.

Preparing Eggs of Petromyzon.t—Dr. A. A. Bohm treats artificially
fertilized eggs with Flemming’s fluid, containing a larger admixture of
osmic acid than is prescribed in the original formula.

* Amer. Nat., xxiii, (1889) pp. 277-9.
+ Arch. f. Mikr, Anat., xxxii. (1889) pp. 634-5.

lod

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 105

After thirty minutes the eggs are washed in distilled water, passed
through 30 per cent. and 70 per cent. alcohol (three hours in each),
preserved in 90 per cent., and cut in paraffin. The sections are fixed to
the slide with albumen, stained with safranin, and mounted in xylol
balsam.

Preparing and Mounting with Pressure Insects entire, as Trans-
parent Objects.*—Mr. T. W. Starr adopts the following method :—

After procuring the insect, place it under a tumbler with a few
drops of ether. When dead, wet it with alcohol, and place it in liquor
potasse, U.S.P., and let it soak until the skin is soft, and until, on
slight pressure, the contents of the intestine can be pressed out through
the natural or, if necessary, an artificial opening. This is best done
under water in a white plate.

When this is effected the object is to be cleaned. Have a camel’s
hair brush in each hand; with one hold the object, and with the other
brush every part of the insect on both sides. Float it on to a glass
slide, and dispose each part in a natural position, either creeping or
flying. Cover this with another glass slip of the same size, and press
gently together, using only sufficient force to make it as thin as possible
without crushing or destroying it. Confine the glasses, with the insect
between them, with a fine brass wire, and place them in clean water, to
remain twenty-four or thirty-six hours; this will give the insect a posi-
tion that is not easily changed, and it is therefore proper that the position
be such as you desire when the insect is finished. Rembve the wire and
open the glasses carefully under water, and float the insect off; give it
another brushing, and let if remain a few hours to remove the potassa.
Transfer it to a small but suitable vessel containing the strongest alcohol
that can be obtained, pursuing the same course as with the water, placing
the specimen between glass slips tied together, and let it remain about
twenty-four hours.

Transfer to a vessel containing spirits of turpentine. It is to remain
in this, kept between the glasses, until all the water is removed. While
in the spirits of turpentine the insect is to be released several times, and
the moisture removed from the glasses, and the insect again confined.
When no moisture is seen to surround the insect, heat the glass slips
containing the insect over a spirit-lamp until the contained turpentine
nearly boils, when, if any moisture is present, it will show its presence
when the glasses are cold.

If free from moisture it is ready for mounting. Floatit on to a suit-
able glass from the turpentine, drop a sufficient quantity of balsam upon
it, examine and see that no foreign substances are present, heat the cover
slightly, and apply in the usual way. After a day or two heat the slide
moderately, and press out the surplus balsam, and place a small weight
upon the cover while drying. After the lapse of a suitable time remove
the surplus balsam, and clean the slide.

In all the operations the utmost cleanliness is essential. The liquids
should be frequently filtered and kept from dust, and a large share of
patience will be found necessary.

After sufficient time has been given to allow the balsam to harden, so
that the cleaning will not displace the cover, remove the surplus from
around the cover-glass with a warm knife, and then moisten a soft tooth-

* Queen’s Mier. Bull., vi. (1889) p. 29.

706 SUMMARY OF CURRENT RESEARCHES RELATING TO

brush with a mixture of equal parts of alcohol and aqua ammonie, and a
slight rubbing will clean the slide with very little danger.

After removing the superfluous balsam and cleaning the slide, finish
by spinning a ring around the cover with a transparent cement.

Preparing Central Nervous System of Lumbricus.*—If the earth-
worm is to be sectioned in toto, it is necessary to remove the sand from
the alimentary canal. For this purpose, place the worm in a glass
cylinder partly filled with fine bits of wet filter-paper. As the papcr is
swallowed the sand is expelled, and at the end of about two days the
alimentary tract is cleansed.

In the study of the ventral cord, Dr. B. Friedlander employed the
following methods :—

Place the worm in water, to which a little chloroform has been
added, and it soon becomes stupefied in an outstretched condition.
Then cut open the body-wall along the median dorsal line, and pin the
edges down in a dish covered with paraffin or wax. After removing
the alimentary canal, the specimen may be treated with a preservative
fluid.

1. Osmic acid 1 per cent. After an exposure of about half an hour,
the worm is sufficiently stiffened to allow the pins to be removed, and it
may then be cut into pieces of any desired length. The pieces are then
left twenty-four hours in the same solution, then washed and passed
through the usual grades of alcohol. Preparatory to imbedding in
paraffin the pieces are saturated with chloroform or toluol. This
method is excellent for the study of the neuroglia-like elements, and is ©
the best for the brain.

2. Preparations treated thirty minutes with osmic acid (1 per cent.)
are transferred to a dilute solution of pyroligneous acid (one part to
three parts water), which reduces the osmic acid very quickly. This
is followed by alcohol as before. The ganglion cells are well
preserved.

3. The preparation is first treated with weak alcohol, then with
stronger grades. After half an hour in 70 per cent. alcohol, it is stiff
enough for removing the pins and for cutting into small pieces. Nerve-
fibres are somewhat contracted by this method, and are thus more easily
distinguished from the surrounding connective tissue.

4, Corrosive sublimate (aqueous sol.) and 50 per cent. alcohol in
equal parts (thirty minutes) gave good preparations of the nerves and
the neural tubes.

For preparations according to No. 3, the best stain is a modified
form of Mayer’s alcohol-carmine, absolute alcohol being substituted for
80 per cent. Sublimate preparations are successfully stained with
Grenacher’s hematoxylin. After half an hour in this staining-fluid, the
preparations are transferred to acidulated alcohol (50 per cent., with a
little hydrochloric acid) half a minute, then placed in alcohol containing
afew drops of ammonia. Connective tissue and nerves are unstained,
while ganglion cells are stained deep blue. ;

The last two methods of staining may be followed by picric acid,
which stains the uncoloured elements yellow. The process is as follows:

After the sections have been fixed to the slide with collodion and the

* Zeitsehr. f. Wiss. Zool., xlvii. (1888) p. 48.

ZOOLOGY AND BOTANY, MIOROSCOPY, ETC. 707

paraffin dissolved with turpentine or xylol, the slide is placed in turpen-
tine containing a few drops of a solution of picric acid in absolute
alcohol. In a few seconds, nerve-fibres, connective tissue, and muscles
are stained yellow. The slide is next to be placed in turpentine con-
taining afew drops of alcohol, to wash away the excess of picric
acid, then in pure turpentine or xylol preparatory to mounting in
balsam.*

Preparing Sections of Spines of Echinus.;—Mr. J. D. Hyatt says
that it is much easier to grind down a number of such sections at one
time than to grind one singly, and he therefore fills a glass tube with
spines, cementing them in place with balsam, and then by means of a
circular diamond-saw slices both tube and contained spines into thin
discs. A number of these discs are cemented by balsam to a glass slip,
and all are ground down together. In order to successfully turn them
over to continue the grinding, they are cemented to the first slip with
thin balsam. The slip to which they are to be transferred is supplied
with thick balsam and inverted over the sections, whereupon, with
proper manipulation, the sections will leave the first slip and adhere to
the second. He mounts seven or eight sections of spines under one
cover, returning them to their desired positions, if displaced in mounting,
by inserting under the cover a needle ground flat and very thin upon
an emery wheel.

Examining a Shell-bark Hickory Bud.{—Dr. H. Shimer writes :—
Cut a longitudinal section near the middle (a somewhat thick section,
1/100 to 1/300 in., is easily cut), transfer it to a slide, apply glycerin
with a brush; after it has pretty well soaked, drain off the superfluous
fluid, warm the slide, apply glycerin-jelly, or better, the author’s new
mounting formula :—Glycerin-jelly, 1 part; Farrant’s medium, 1 part;
glycerin, 1 part, thoroughly mixed. Apply a heavy cover-glass, press it
down a little, at length seal the edges with cement, and the result is a
very beautiful specimen permanently mounted. -

Examine it with a 1 in. objective, the stand being in the sunshine
with a piece of sky-blue blotting-paper over the mirror for a background,
and we have a more beautiful and instructive specimen than a 1/1000 in.
section made in celloidin. The arrangement of the leaves and the hairs
are all that could be desired. Even the cellular structure can be studied.
This process is given, not to supersede other fine methods, but only as
an easy method to aid in the study of a beautiful bud. If it isa side
bud it will show the origin of the bud in the side of the limb and its
progress to the surface.

White’s Botanical Preparations.§—Mr. C. W. Smiley deseribes the
botanical preparations of Mr. Walter White. Though not pretending to
take the place of objects mounted in the usual way, yet, being inclosed
in a transparent envelope, they are available for immediate examination,
either without or with magnification, in many cases even with the higher
powers of the Microscope.

* Amer. Nat., xxiil. (1889) pp. 189-90.

+ Journ. New York Micr. Soc., v. (1889) p. 44.

{ Amer. Mon. Micr. Journ., x. (1889) p. 104. Sce also p. 136.
§ T.c., pp. 110-1.

708 SUMMARY OF CURRENT RESEARCHES RELATING TO

The following items from the catalogue will give some idea of the
objects prepared :—
3. Orchid leaf. Fibro-spiral cells.
19. Yew. Isolated wood cells.
27. Brake fern. Scalariform vessels.
53. Pampas grass. Closed vascular bundles.
75. Mistletoe. 'Thickened cuticle cells.
99. Hucalyptus. Oil glands in leaf.

134. Begonia. Axile placentation.

In many cases the objects have been stained, either singly or doubly,
and some stained three years ago have not faded. Their very low cost
commends them to every student of biology or collector of microscopic
objects.

They may be mounted in either resinous media (dammar, benzol-
balsam), or glycerin or glycerin-jelly. Mr. White’s instructions for
mounting are as follows :—“ Carefully separate the inclosing films, and
remove the object. If for resinous media, soak in spirit of turpentine
till clear, rinse in a fresh portion of the same, then drain, transfer to
the cover or slide, and finish in the usual way. For glycerin :—If the
object be oily, first wash out the oil with strong methylated spirit till
clear, transfer to a mixture of glycerin and water, equal parts, in which
let it remain an hour or two, then mount.

“Minute objects, such as isolated cells, should be transferred on the
point of a scalpel to a slide (or cover), and separated with a needle in a
drop of spirit; then, if for glycerin, mount while still moist; but if for —
resinous media, allow to dry, then moisten with a drop of turpentine
before applying the medium. Spiral and other vessels, and long fibre
cells, which mat together, should be soaked in a drop of weak spirit, and
a few of the most perfect picked out under a simple lens.”

Bacteriological Technique.*—Dr. C. Giinther suggests that agar
plate cultivations may be preserved on slides by cutting out a thin layer
and then imbedding in glycerin. The specimen is to be mounted on the
slide in the usual way.

The author also suggests that the condensation water of potato culti-
vation in test-tubes may be prevented from coming in contact with the
potato by resting the latter upon a piece of glass tube about 2 cm. long.
The latter lies on the bottom of the test-tube. In other respects the
author advises Hueppe’s technique.

Beck, J. D.—A Slide of Hints and Suggestions.

[Cleaning slides—How to dispose of excess of media on slides—Clipping
covers—Centering and ringing clipped covers—Cements—Final cleaning of
slides—Double-staining animal tissues—Pale copal varnish—Black elastic
varnish—Aluminium palmitate copal varnish. ]

The Microscope, 1X. (1889) pp. 205-12.
CANFIELD, W. B.—On the Microscopical Examination of Urinary Sediment.
Queen’s Micr, Bulletin, VI. (1889) p. 26.
CHADWICK, H.—Mounting Insects in Balsam without pressure.
Queen’s Micr. Bulletin, VI. (1889) pp. 31-2.
Dvurour, L.—Revue des travaux relatifs aux Methodes de Technique publiés en
1888 et jusqu’en avril 1889. (Review of the works relating to methods of
Technique published in 1888 and down to April 1889.)

[1. Methods of preservation and culture. 2. Processes for treating the
sections. 3. Microscopy. 4. Photomicrography. 5. Various. ]

Revue Gen, de Botanique, I. (1889) pp. 280-92, 343-56 (4 figs.).

* Deutsch. Med. Wochenschr., 1889, No. 20.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 709

HAaukYArp, E.—The Collection and Preparation of Foraminifera.
Trans. Manchester Mier. Soc., 1888, pp. 53-9 (1 pl.).
LatTHaAm, V. A.—Histology of the Teeth—Notes on Methods of Preparation.
Journ. of Microscopy, II. (1889) pp. 137-52.
RANVikER, L.—Traite technique @’histologie. (Treatise on histological technique.)
2nd ed., 870 pp. and 444 figs. S8vo, Paris, 1889.
Rogers, F. A.—Preparation of Drug Sections for Microscopical Examination.
Queen’s Micr, Bulletin, VI. (1889) pp. 12-3,
from ‘Rocky Mountain Druggist.’
Tyas, W. H.—Methods of Hardening, Imbedding, Cutting, and Staining Animal
Sections, and Methods of Mounting the same.
Trans. Manchester Micr. Soc., 1888, pp. 83-5.
W HITELEGGE, T.—On Collecting, Cleaning, and Mounting Foraminifera.
Ibid., pp. 12-4.
“2 » Notes ofa Method of killing Zoophytes and Rotifera.
[Chloroform and spirits.] Lbid., pp. 14-5.

(3) Cutting, including Imbedding and Microtomes.

King’s Microtome.*—Mr. J. D. King claims for his microtome no
superiority over other first-class instruments for ordinary histological
work in animal tissues, but it is designed especially for hard service in
botanical work or for cutting any hard material, which requires absolute
rigidity in the instrument.

The knife e is attached to a heavy nickel-plated iron carriage A, by a

Fic. 95.

a

Hil

steel clamp and shoe b and ¢, with milled-head screws a. The carriage
runs on a solid iron track h and B, which is held to a table by clamp
screw k.

For cutting very hard objects, like the wiry stems of plants or the

* The Microscope, ix. (1889) pp. 76-7 (1 fig.).

710 SUMMARY OF CURRENT RESEARCHES RELATING TO

chitinous skeletons of insects, there is an attachment with a very stout
blade, on the principle of a carpenter’s plane d, which screws on to the
carriage in place of the knife, and like the knife it can be used straight
across or obliquely.

Diameter of well 7, 7/8 in.; depth of well, 1} in.; depth of well with
chuck L, 1 in.

For cutting soft material, paraffin may be cast directly into the well,
or into a chuck (not shown) which is held firmly by being screwed into
the bottom of the well. The adjustable chuck L is intended for harder
material.

Microtome No. 1 gauges to 1/10,000 of an inch by turning the
rachet g one click, but can be set to any desirable thickness less by the
adjustable are N. No. 2 gauges to 1/2000 inch, adjustable like No. 1.

Paoletti’s Improved Microtome.*—In Sig. V. Paoletti’s improved
microtome the advantage aimed at consists in reducing the number of
movements, and thus to diminish the tendency to inequality in the thick-
ness of the sections. With this intent the knife is kept fixed, and the
object-carrier alone moves. The microtome stand consists of a heavy
cast-iron base, to which is fixed a vertical upright. To this latter is
pivoted a largish steel plate at the end of two horizontal arms. To this
plate is fixed the object-carrier, which receives horizontal and vertical
movements from a micrometer screw placed beneath it, and with which
it is connected by means of a special arrangement.

The knife is fixed by a clamp in any desired position to the vertical
upright.

On a dial-plate, the index of which points against the steel plate, are
marked numbers from 1-12; these correspond to hundredths of a milli-
metre, and serve to indicate how far the object-carrier ascends while it is
moving horizontally at the same time.

Method for keeping Serial Sections in order during manipula-
tion.|—Dr. L. Darkschewitsch has used the following method for four
years for keeping sections of brain and cord in their proper order. A
glass tube or wine-glass of the diameter of the sections to be cut is filled
with spirit. Discs of filter-paper are also cut of the size to conveniently
fit within the vessel. These paper slips are numbered, and having been
arranged in their proper order, soaked in spirit. As the sections are
made, the paper slip is laid thereon, the two drawn off together, and laid
in the vessel, the paper side downwards.

When the vessel is full of the serially arranged sections, the whole
series may be stained in situ. For this purpose the spirit is poured off,
and, if necessary, the series is washed with distilled water before the
staining solution is poured in. If Weigert’s hematoxylin method is to be
used, the solution is poured in after the spirit has been removed, and the
glass vessel is then placed in a hot box for twenty-four hours. The
staining solution is then poured off, and the series washed with distilled
water until no more dye is given off. ‘The sections are next taken out
separately, and placed on a flat vessel (e.g. a plate) filled with the
decolorizer, wherein they remain until the decoloration is complete.
After having been thoroughly washed they are returned to the glass

* Atti della Societa Toscana di Scienze Naturali, vi. (1888) p. 180.
+ Zeitschr, f. Wiss. Mikr., vi. (1889) pp. 43-5,

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. ve kil

vessel, where they are dehydrated with spirit. The rest of the treatment
(clearing up and mounting in balsam) is done in the usual way.

Suimer, H.—Section-cutting in the Cold. The Microscope, 1X. (1889) pp. 275-7.

(4) Staining and Injecting,

New Method of Staining the Flagella and Cilia of Micro-
organisms.*—Prof. F. Loeffler has devised a new method for staining
micro-organisms, and which is especially intended to demonstrate cilia
and flagella. That the method is successful is shown by the results,
and in photographs the flagella are perfectly seen, as also are cilia of
infusoria and monads. The method essentially depends on submitting
the preparations to the action of a mordant.

From previous experience it had been found that the capsule of
pneumonia cocci were stained grey by ink. Hence tannate of iron sug-
gested itself, and after many trials the author hit upon the following
procedure which he pronounces to be satisfactory.

The mordant is prepared by adding a watery solution of iron
sulphate to an aqueous 20 per cent. solution of tannin, until the whole
fluid turns a black violet. To this fluid is then added 3-4 ccm. of log-
wood solution (1 part wood to 8 parts water). The solution should be
kept in well-stoppered bottles and 4-5 ccm. of a 5 per cent. solution of
carbolic acid added in order to keep it.

The staining fluid is made by adding 1 ccm. of a 1 per cent. hydrate
of soda solution to 100 ccm. of anilin-oil water. This alkaline anilin
water is then mixed with 4-5 g. of methyl-violet, methylen-blue, or
fuchsin (solid) in a flask, and the ingredients mixed by shaking. When
required the requisite quantity of fluid is filtered off.

The material to be examined must form a very thin layer upon the
cover-glass ; hence the fluid, &c., containing the bacteria must be diluted
with distilled water, and from the solution the specimen taken, so that
the film upon the cover is very thin.

After having been dried in the air and fixed in the flame, the
mordant is poured over the film, and then the cover is held over the
flame until the fluid begins to evaporate. The mordant is then washed
off with distilled water, especial care being taken to remove all traces
from the edge of the cover.

The next step is to filter a few drops of the stain (fuchsin best) upon
the film. This is allowed to act for a few minutes and then the cover
is very carefully warmed over the flame. As the fluid becomes warm
the film darkens, and when it is of a black-red hue the stain is washed
off with distilled water, and the preparation is then ready for micro-
scopical examination.

Such is the principle of the author’s method, but certain variations
are also given. One of these is for showing delicate spirals in prepara-
tions of typhoid and potato bacilli. Here a few drops of acetic acid
13 per cent. are added to the solutions. It was also noticed that ferri-
tannate gave more satisfactory results with these bacilli than ferro-
tannate, but with other bacteria, such as those of cholera, the reverse
was the case.

* Centralbl. f. Bakteriol. u. Parasitenk., vi. 1889) pp. 209-24 (8 photos.).

712 SUMMARY OF CURRENT RESEARCHES RELATING TO

Staining differences in resting and active Nuclei in Carcinoma,
Adenoma, and Sarcoma.*—Dr. A. Kossinski who has been investigating
the chromoleptic substances in cell-nuclei, comes to the conclusion that
the resting nucleus is differently constructed from the active one. The
author examined twenty different tumours, and pieces of these were
hardened in sublimate solution or 97 per cent. alcohol, imbedded in
paraffin and cut up into sections 0:01 mm. thick. Of the numerous
stains used the preference is given to safranin and dahlia. The former
was used in a 0°5 per cent. watery-spirituous solution; the latter in
concentrated alcoholic solution. If, however, a double stain were used,
a combination of hematoxylin with after-staining with safranin gave by
far the best result. With this method the resting nuclei were coloured
blue-violet, the karyokinetic or active nuclei a deep red. The method
adopted was to stain the section which had been fixed on the slide for
nearly a minute with the logwood solution: then to wash it with a 1 per
cent. watery alum solution for two to four minutes, then with distilled
water for three to five minutes, and lastly with alcohol for one to
three minutes. The safranin solution was then allowed to act for
twenty to thirty minutes, after which the excess was extracted with
alcohol.

Other combinations such as nigrosin and safranin, indigo-carmine and
safranin, and eosin or crocein with dahlia sometimes gave fair results.

Rapid method of Staining the Tubercle Bacillus in liquids and
in tissues.t—-This method, the invention of Dr. H. Martin, depends on
the combination of heat and the proper dyes. The pigments used are ~
crystal violet (hexamethyl violet) and eosin as a contrast stain. The
stain is made in two solutions:—(1) Crystal violet, 1 g.; alcohol, 95 per
cent.,30ccm. (2) Carbonate of ammonia, 1 g.; distilled water, 100 ccm.
Some of solution 2 is poured into a watch-glass, and so much of No. 1
added until the mixture stains filter-paper deeply. This solution is
heated until it almost boils.

Cover-glass preparations put up in the usual way are stained in this
solution for about one minute, and are then decolorized in 10 per cent.
nitric acid (four to five seconds), washed in 95 per cent. spirit, dried or
after-stained with the following solution :—Eosin, 1 g.; alcohol, 60 per
cent., 100 ccm. This last stain only requires half a minute (cold), The
staining of sections is the same as the foregoing, except that the author
recommends that after alcohol the sections should be passed through oil
of cloves, then turpentine and xylol. The solution of nitric acid should
be 25 per cent. instead of 10 per cent. .

Staining and Detection of Gonococci.t—Dr. J. Schiitz gives the.
following process for differential staining of gonococci :—Prepare the
cover-glasses in the ordinary manner and immerse them for from five to
ten minutes in a saturated solution of methyl-blue in a 5 per cent.
aqueous solution of carbolic acid. Wash in distilled water and immerse
for a few seconds in very dilute acetic acid (one minim of the acid to
drachm of water). Washing in distilled water completes the process,
though if desired, a dilute solution of safranin may be employed as a

* Wratsch, 1888, Nos. 4, 5, 6. Cf. Zeitschr. f. Wiss. Mikr., vi. (1888) pp. 60-2.

+ Annales de l'Institut Pasteur, 1889, p. 160.

+ St. Louis Med. and Surg. Journ,, Ivii. (1889) p. 44, from ‘Miincher Med.
Wochenschrift,’ 1889, No. 14.

Ld

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 113

complementary stain. Otherwise the gonococci will appear stained blue
on a quite decolorized background.

Dr. F. L. James says * that this process differs in scarcely any degree
from that which he has used for a long time for staining gonococci, and
he has found it quite good. The ordinary alkaline solution of methyl-
blue stains the gonococci a deeper blue than the surrounding tissues,
and does not readily bleach out from the latter.

Simple and rapid Method of staining Bacillus tuberculosis in
sputum.j—M. E. Dineur gives the following as being a very convenient
method for clinical purposes for staining the tubercle bacillus :—

(1) Saturated alcoholic solution of fuchsin.
ta 25 per cent. solution of carbolic acid in glycerin.

(3) Pure glycerin (or diluted with an equal quantity of water).

(4) Sulphuric acid, 1 in 5.

Several drops of sputum are placed in a watch-glass and then mixed
with two or three drops of the fuchsin solution. A drop of the car-
bolated glycerin is then mixed up with the stained sputum. The mix-
ture is then heated for several minutes to a temperature of 80°-100°. A
piece the size of a pin’s head is then removed with a needle to a drop of
glycerin, placed on a slide, and the cover-glass imposed. A drop of the
sulphuric acid is then run under the cover-glass. As the acid eats its
way in, everything but bacilli are decolorized. These retain the stain
sufficiently long to be easily recognized by microscopical examination
made in the usual manner.

New Method for staining the Tubercle Bacillus.t—Dr. K. A.
Norderling has devised the following method, which he states is very
safe and easy :—

The staining is done in the usual way by means of the Ehrlich
fuchsin solution. The cover-glass is then washed in distilled water
and afterwards immersed in a saturated solution of oxalic acid. It must
remain therein until it is completely decolorized, when it is taken out,
dried, and immersed in a weak solution of methylen-blue until it has
received a light-blue colour (about one-half to two minutes). After this
it is dried again and finally mounted in balsam. All is now coloured .
blue except the bacilli, which have a beautiful red colour.

Staining and mounting Elements which have been treated with
Caustic Potash or Nitric Acid.§—At the Buffalo meeting of the
American Society of Microscopists, a communication was read on this
subject from Professor Simon H. Gage and Mrs. §. P. Gage. ‘I'he main
features of the technique of mounting histological elements which have
been treated during the process of isolation with either nitric acid or
potassium hydrate, is as follows :—

When nitric acid has been the agent in isolating the elements, the
first step is to soak the latter in water, to remove all traces of free acid ;
then transfer to a slip of glass on which has been placed a drop of
picrated glycerin. Separate or arrange the fibres, and remove excess of
glycerin with blotting-paper. If desired to stain, place in Koch’s red

* St. Louis Med. and Surg. Journ., lvii. (1889) p. 44, from ‘Muncher Med.
Wochenschrift,’ 1889, No. 14.
t+ Bull. Soc. Belg. Micr., xv. (1889) pp. 59-62.
t Queen’s Micr. Bulletin, vi. (1889) p. 21, from ‘ Medical Record.’
St. Louis Med, and Surg. Journ., lvii. (1889) p. 233.

1889. 3 D

714 SUMMARY OF CURRENT RESEARCHES RELATING TO

tubercle bacillus stain (dilute), and leave for twelve hours, remove to a
slip containing alcohol of 20°; replace latter by alcohol of 50°, and
finally of 90°; clear, and fix with clove-oil collodion and mount in
Canada balsam. If it is not desired to mount the object at once, it can
be placed in saturated alum water after removal of the glycerin, after-
wards stained with hematoxylin and mounted in any way desired.
Where caustic potash has been used as the isolating material the
latter may be neutralized by the use of a 60 per cent. solution of acetate
of potassium. There should be a plentiful supply of the neutralizing
agent used, changing the charge two or three times. After pouring it
off for the last time, wash with plenty of a saturated aqueous solution of
alum, stain with alum carmine, or hematoxylin, and mount as desired.

Staining the Walls of Yeast-plant Cells.*—In demonstrating the
two membranes of the cell of the yeast-plant, Prof. 8. H. Vines found that,
by first staining the cells in methyl-violet, washing in distilled water,
and then transferring to anilin-green for some hours, in some instances
the inner membrane appears of a violet colour, while the outer layer
takes a slight green.

Solubility of Fat and Myelin in Turpentine Oil after the action
of Osmic Acid.|—Prof. W. Flemming states that fat having been
blackened with pure osmic acid uever loses colour, even though exposed
to direct sunlizht for hours and afterwards treated with turpentine. This
statement is made in consequence of a communication of M. C. Dekhuyzen,
who found that preparations treated with Flemming’s chrom-osmium- .
acetic acid mixture became decolorized when treated with turpentine oil
or turpentine balsam. M. ©. Dekhuyzen’s explanation of the action is
that turpentine oil acquires oxydizing properties by exposure to direct
sunlight. This may or not be, but if the author’s observations are
correct it is obvious that the decoloration must be due to the association
of the acetic or chromic acid,

Couw’s (A. C.) New Slides.

[‘‘ New method of staining tissues, and particularly nervous structures. This
method is strikingly brought out by the slide showing sections of the lumbar
and dorsal region of the human spinal cord in four colours. This new stain
is particularly effective for photomicrography, as is proved hy another slide
mounting a transverse section of the left median human nerve. The other
slides, mounted with the new staining, are very interesting :—Transverse
section through the spinal cord and stomach of a snake, showing a semi-
devoured lizard, and also section of the lizard’s spinal cord ; section through
the cervical region of snake, showing spinal cord, cesophagus, &c.; and an
effective mount (for microscopic purposes), giving vertical and horizontal
sections of the human scalp, showing the hair-follicles, &e.’’]

Sci.-Gossip, 1889, p. 184.
Staining Tubercle-Bacilli. Journ. of Microscopy, II. (1889) pp. 165-6,
from ‘ National Druggist.’

(5) Mounting, including Slides, Preservative Fluids, &c.

Hints on Mounting Objects in Farrant’s Medium.t—Mr. C. M.
Vorce writes :—Attention is being turned again to this old but too much
neglected medium, the preparation of which by all the published formule
is attended with much trouble and vexation. The chief difficulty is in

* Journ. of Microscopy, 1888, p. 12.
+ Zeitschr. f. Wiss. Mikr., vi. (1889) pp. 39-40.
${ Amer. Mon. Micr. Journ., x. (1889) pp. 149-50.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 715

filtering the viscous mass, for, notwithstanding the caution always given
against stirring the mass to mix it thoroughly, in my own experience the
bubbles formed in stirring have uniformly disappeared on long standing
in a warm room. Air-bubbles in the completed mount, however, exhibit
all the obstinacy with which they have been credited when the mass is
prepared on the formula commonly given, viz. two parts each by weight
of gum acacia and distilled water, and one part of glycerin. ‘lhe gum
is dissolved in the water, the glycerin added, the mass filtered, and a little
camphor added to prevent mould. This makes a quite viscous mass which
quickly dries around the edge of the cover, but from which air-bubbles
cannot be driven out nor poked out if once imprisoned under the cover.

For such objects as are usually mounted in pure glycerin a much
thinner preparation of Farrant’s medium is very convenient, and is made
by simply increasing the proportion of glycerin to gum. Another useful
medium, which dries readily but shrinks more than the others, is made
by taking by weight 6 parts gum, 4 parts white sugar, 16 parts water,
and 6 parts glycerin, prepared as described, A still further modification
is made by taking 8 parts gum, 4 parts white sugar, 2 parts gelatin,
20 parts water, and 12 parts glycerin. Dissolve the gelatin first, then
add the gum and sugar, and lastly the glycerin. This mass never dries
completely hard, but only to a tough, leathery consistence. In all cases
a little gum camphor, phenol, clove-oil, or thymol should be added to
the completed mass to prevent fungoid growth.

In the preparation of Farrant’s medium on any formula, much time
and annoyance may be saved by making the watery solution of gum, &c.,
much thinner than it is required to be, and after filtration evaporating it
to the consistence desired, and then adding the glycerin. I always add
to the water in the beginning an ounce or so of a weak solution of chloral
hydrate, and add gum thymol to the finished mass; a piece the size of a
large pin-head will do for an ounce of medium.

In mounting in any of these gum media, much trouble is saved by
first macerating the object in some of the thin medium for a longer or
shorter time according to its nature—longer for dense objects than for
thin ones—and then arranging the object on the slip in some of the thin
medium, allowing most of the water to evaporate (protected from dust),
and then adding the thick medium and applying the cover, using a light
spring clip to retain it in place. Air-bubbles will not be included by
this method.

If a surplus of the medium was used so that much has escaped around
the cover, this excess should be cleaned away within twenty-four hours
after the cover was placed, while it is still soft and tough. If the clean-
ing is delayed until the mass outside the cover is hard, the cover will
often be moved or pulled out of position by the removal of the outer
mass. As soon as the partially cleaned slide has become quite dry, the
slip should be placed on a turntable, and the slide cleaned close up to
the cover, using a knife-blade or chisel-point to cut away the gum, and a
moist rag or folded blotter to finish. Then add successive finishing rings
of some resinous cement. Objects thus mounted will prove as durable as
balsam mounts; there will be no shrinkage or distortion of soft parts,
as often occurs with objects in glycerin; the most delicate and colourless
of structural details are well shown, and the objects photograph extremely
well.

Air-bubbles need not be included in the mounts, but if unfortunately

716 SUMMARY OF CURRENT RESEARCHES RELATING TO

present they may be removed by placing the slide in a beaker or glass
vessel in which it can lie flat, putting in distilled water to cover the slide,
and after standing a few minutes, place the vessel on a sand-bath, when
the bubbles will soon emerge from under the cover and rise to the sur-
face of the water. The slide is then to be carefully removed, wiped, and
some of the thick medium spun round outside the edge of the cover,
which will in drying fill the space under the cover without admitting
any air. This is much better than to remove the cover or to try to poke
out the bubble, as the removal or displacement of the cover is very likely
to tangle up and destroy the object.

New Cell.#—Mr. C. H. H. Walker, of Liverpool, has devised a new
cell for large mounts. They are rectangular in shape, and are made of
one standard size, 11 in. by 5/16 in. They are also made with three
sides only for use as live-troughs, &c. The thickness varies from 1/24 in.
to 1/12 in. Ifa deeper cell be required, two or more can be cemented
together.

Mounting in Fluosilicate of Soda.j—Mr. E. P. Quinn states that
sodium fiuosilicate, which is sold as a disinfectant under the name of
Salufer, is a very good medium for preserving the green colouring
matter of plants, and that owing to its slight solubility in water
(0-4 parts in 100) it possesses the further advantage of causing little
alteration in the shape of the cells.

The Bidwell Cabinet.t—In this cabinet, the invention of Dr. W. D.
Bidwell, “the drawers contain twelve slides each, and are made of a
single piece of seasoned black walnut, 74 in. by 8 in. and 3/8 in. thick.
The compartments are made with a 1-in. chisel, making six cuts 1/4 in.
apart and 1/4 in. from the side on each side, and then cuts corre-
sponding to these 3 in. towards the middle of the drawer. Then a piece
is easily chipped out between each pair of cuts, leaving twelve drawers
which easily hold the slides, separated down the centre by a ridge 3/4 to
lin. wide. Taking a single cut with a gouge out of this ridge opposite
each trough makes a convenient place to slip inthe finger-nail to raise a
slide. Then the drawers are complete, strong and firm, and very easily
and cheaply made. Cut a shoulder on each side of the drawer, and a
cabinet is made which will take less than half the time or expense to
make of any other, and when done the slides are firmly held, each in its
own compartment, and available for inspection or removal, and no
danger of removing the cover-glass or label by hasty removal or the
motion incident to carrying.”

(6) Miscellaneous.

Microscopical Atlas of Bacteriology.s—Dr. C. Fraenkel and Dr.
A. Pfeiffer are issuing in parts an atlas which is intended to show the
microscopical appearances of micro-organisms. The illustrations have
been reproduced from photomicrographs, and possess at the same time
the faults and virtues of this process. The cover-glass preparations are
shown under a magnification of 1000, and sections of 500. Colonies

* Sci.-Gossip, 1889, p. 184. + Trans. Manchester Micr. Soc., 1888, p. 75.
~ Amer. Mon. Micr. Journ., x. (1889) pp. 184-5.
§ ‘ Mikroskopischer Atlas der Bakterienkunde, 8vo, Berlin, 1889 (pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 717

from plate cultivations are represented under a low power, and those
from test-tube cultivations of the natural size.

As the authors of the work are Koch’s assistants, their work may be
accepted as representing micro-organisms faithfully.

Detecting Alterations in Manuscripts.*—As an accessory to the
use of the Microscope, photography is recommended by Mr. G. G.
Rockwood. He has for years been in the habit of photographing manu-
scripts, models, books of accounts, cheques, and drafts, whenever their
genuineness was questioned. The process sometimes makes legible
figures, amendments, and alterations which even the Microscope does
not fully bring out. This is due to the extreme sensitiveness of photo-
graphic plates to shades of colour. With the new “auto-chromatic” or
colour-sensitive plates almost imperceptible stains on old yellow paper
have been made clear and legible.

Cock, G. B.—The Microscope in the Mill. Queen’s Micr. Bulletin, VI. (1889) p. 10.

* Amer. Mon. Micr. Journ.,, x. (1889) p. 126.

(748 )

PROCEEDINGS OF THE SOCIETY.

Tur first Conversazione of the Session was held on the 28th November,
1888.

The following objects, &c., were exhibited :—

Mr. C. Baker :—(1) Portable Medical Microscope. (2) Zeiss’s Apo-
chromatic Objectives.

Messrs. R. and J. Beck :—(1) Amphipleura pellucida, with new 1/12 in.
Oil-immersion Objective. (2) Circulation of Sap in leaf of Vallis-
neria, with 1/6 in. Binocular Objective.

Mr. Bolton :—Limnias annulatus.

Mr. Crisp :—Griffith Club Microscope with new fine-adjustment.

Mr. F. Fitch:—(1) Anatomy of Golden-banded Fly 9. (2) Repro-
ductive Organs of 9 Harwig.

Mr. H. E. Freeman :—(1) Section of Eye of Tadpole. (2) Section of
Flower of Horse Chestnut.

Mr. H. F. Hailes:—Longitudinal Section of Fuselina from Iowa,
U.S.A.

Mr. J. D. Hardy:—(1) Nummulitic Limestone from the Pyramids.
(2) Eozoon canadense.

Mr. J. Hood :—WMelicerta jairus and M. tubicolaria.

Mr. S. W. Ireland: —(1) Nodosaria scalaris Batsch, var. separans
Brady. (2) Webbina clavata J. & P., parasitic on grain of quartz.

Rev. T. 8. King :—Insects in Amber.

Mr. R. T. Lewis:—(1) Lecanium acuminatum. (2) Living Larve of
two species of Psychide from Natal.

Mr. R. Macer :—Ciniflo atrox, showing spinnerets of a living Spider.

Mr. 8. J. M‘Intire :—(1) Pupa of Cat Flea. (2) Section of Eye of Privet
Moth.

Mr. G. E. Mainland:—Braula ceca. Parasite of the Hive Bee.

Mr. A. D. Michael :—Principal Ganglionic Chain and Proventriculus
(Gizzard) of Staphylinus (Coleoptera), one of the very minute forms.

Mr. B. W. Priest :—Internal Casts of Foraminifera. Macassar Straits,
45 fathoms.

Messrs. A. Pringle and C. Lees Curties.—Photomicrographs of Bacteria,
Physiological preparations, Diatoms, &c., exhibited with the Oxy-
hydrogen Lantern.

Mr. ©. Rousselet :—Limnias cornuella, a new Rotifer.

Mr. G. J. Smith:—(1) Olivine Dolerite, Glacial ° Drift, Finchley.
(2) Basalt (columnar ) with Olivine, Erpel, Linz, Rhine. (8) Micro-
pegmatite. (4) Pikrite, Tringenstein. (5) The Fayette Meteorite,
Bluff Settlement, Colorado River, Bluff Co., Texas. (6) Hjected
blocks of Trachytic Lava from the Tuff of the Lacher See, Eifel,
Prussia.

Mr. W. T. Suffolk:—Scale of Morpho menelaus mounted in oil of
cassia.

Mr. J. J. Vezey :—Salivary glands of Hristalis tenax.

Messrs. Watson and Sons:—(1) Amphipleura pellucida, with 1/12 in.
Apochromatic Objective by Reichert. (2) 'l'entacle of Sea Anemone
(Actinia). (3) Trans. Section of Lamprey through region of Ovary,

PROCEEDINGS OF THE SOCIETY. 719

Kidneys, &c., double stained. (4) Long. Section of Vertebrae of Human
Fetus, two months, showing centres of ossification. (5) Group of
Diatomacee ; wheels of Chirodota, Butterfly scales, &c.

Mr. C. West:—(1) Nodosaria consobrina @’Orb. (2) Cristellaria tenuis
Bornemann.

The second Conversazione of the Session was held on the lst May,
1889.
The following objects, &c., were exhibited :—

Mr. J. Badcock :—Lophopus cristallinus.

Mr. C. Baker :—(1) Zeiss’s new cheap Oil-immersion Objective 1/12 in.
N.A. 1°20. (2) Zeiss’s Apochromatic 8-0 mm, (1/3 in.). (3) Zeiss’s
Apochromatic 6°0 mm. (1/4 in.). (4) Nelson Model Microscopes.
(5) Portable Binocular Microscope. (6) Portable Medical Micro-
scope. (7) Asterina gibbosa. (8) Actinomycosis in tongue of Cow.
(9) Zeiss’s Apparatus for Monochromatic Light.

Dr. G. P. Bate:—(1) Amphipleura pellucida, with 1/16 in. (2) Podura
scale with 1/16 in.

Messrs. R. and J. Beck:—(1) Human Spermatozoa showing filament.
(2) Podura scale with 1/12 in. Oil-immersion.

Mr. W. A. Bevington :—Planchonia fimbriata, a new coccid from British
Guiana.

Mr. Bolton :—(1) Cristatella mucedo, young stage. (2) Larve of Lepto-
phlebia marginata. ;

Mr. W. G. Cocks:—(1) Epistylis. (2) Stephanoceros Eichhornii.

Mr. A. C. Cole:—(1) Section of Hye of Infant. (2) Ditto of Pike.
(3) Series of sections of Snake which was killed soon after it had _
devoured a Lizard. Sections through the Lizard are seen in the
stomach of the Snake, whilst the stomach of the Lizard is full
of Insects, so little digested that the species are recognizable.
(4) Triceratium undulatum, Oamaru.

Mr. E. Dadswell :— Conochilus volvow.

Mr. J. Deby:—(1) Microscope by Baker and Son, London. (2) Ditto
by Chevalier, Paris. (8) Ditto by Oberhauser, Paris, 1838. (4) Ditto
by Plossl, Vienna. (5) Ditto by Seibert, Wetzlar. (6) Brugsmannia
Lowi. Stained sections of the ovary and stamens, exhibiting the
gradual development of the male and female organs out of apparently
homogeneous axial parenchyma. (7) Sponge spicules, the cavities
of which are filled by a siliceous coloured core, supposed to have
replaced the original living protoplasm.

Mr. F. Enock :—Slides showing life-history of the Hessian Fly, Ceei-

domyia destructor.

Mr. R. T. Lewis:—(1) Male of Icerya purchasi from Natal. (2) Spinous
hairs on Larva sp. (?) from Natal.

Mr. R. Macer :—Carchesium polypinum ?

Mr. G. E. Mainland :—(1) Linyphia montana g , Eggs and Pupal Organs.
(2) Walckenaera acuminata 9, Eyes on prominence.

Mr. E. M. Nelson :—Apparatus for exhibiting 1/2500 of an inch without
a lens.

Mr. F. A. Parsons : —Cordylophora lacustris.

Messrs. Powell and Lealand:—Amphipleura pellucida, with 1/12 in.

720 PROCEEDINGS OF THE SOCIETY.

Apochromatic Oil-immersion, N.A. 1:40, and Apochromatic Oil-
immersion Condenser, N.A. 1°40.

Mr. B. W. Priest :—Polyzoa, &c., recent and fossil.

Messrs. A. Pringle and E. M. Nelson:—Photomicrographs of Bacteria,
Physiological preparations, Diatoms, &c., exhibited with the Oxy-
hydrogen Lantern.

Mr. C. Rousselet:—(1) Notops brachionus. (2) Brachionus pala.
(3) Brachionus argularis. (4) Triarthra longiseta, &e.

Mr. G. J. Smith :—Basalt (Rowley Rag), with contemporaneous vein of
more acid rock, Rowley, Staffordshire. Enstatite Diabase, Pen-
maenmawr. ( 2) Hornblende Porphyrite (altered Andesite), Old Red
Sandstone conglomerate, Stonehaven, Scotland. Polarized light.
(3) Olivin Dolerite, Knitellan, Scotland; fissures in Olivin filled
with secondary Magnetite. (4) Pitchstone, Island of Ponza; —
state of tension. Polarized light.

Mr. T. F. Smith:—(1) Abbe Diffraction Plate with central stops.
(2) Photographs of Diatom structure.

Mr. W. T. Suffolk :—Cireulation in Anacharis alsinastrum. Oil-immersion
1/12 in.

Mr. W. H. Tyas:—Series of Histological Slides prepared by Mounting
Section of the Manchester Microscopical Society.

Mr. J. J. Vezey:—(1) Larva of Hchinus (Pluteus). (2) Arbacia
pustulosa.

Messrs. W. Watson and Sons :—(1) Pollen and sexual organs of Scarlet
Lychnis. (2) Type slide of Diatoms from Simbirsk. (8) Kidney -
of Snail. (4) Meibomian glands in human eyelid. (5) Seed of
Maize, showing Embryo, Endosperm, &c. (6) Tentacle of Cuttle-
fish showing suckers in vertical section.

The Journal is issued on the second Wednesday of
February, April, June, August, October, and December.

‘ed To Won-Fellows, |
f 1889. Part 6. DECEMBER. {Price Bs.
JOURNAL
OF THE

ROYAL
MICROSCOPICAL SOCIETY;

CONTAINING ITS TRANSACTIONS AND PROGEEDINGS,

AND A SUMMARY. OF CURRENT RESEARCHES RELATING TO

ZOCOLOGS AND BOtA NS
(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.L.S., F, JEFFREY BELL, M.A., F.ZS.,
Lecturer on Botany at St. Thomas's Hospital, Professor of Comparative Anatomy in King’s College,

JOHN MAYALL, Jon., F.Z.8.; R. G. HEBB, M.A., M.D. (Cantab.),
AND
J. ARTHUR THOMSON, M.A.,
Lecturer on Zoology in the School of Medicine, Edinburgh,
FELLOWS OF THE SOCIETY.

WILLIAMS & NORGATE.
LONDON AND EDINBURGH.

Abs

PRINTED BY WM. CLOWES AND SONS, LIMITED,] [SFAMFORD STREET AND CHARING CROSS,

CONTENTS.

——

TRANSACTIONS OF THE Socrery—

‘PAGE.

XI.~-On tur Errrot or ILLUMINATION BY MEANS OF “Wintawece”: a

Conzs or Licut. By Prof. E. Abbe, Hon, F.R.MS. —
SON

GSgOR) see A s/ oes

. SUMMARY OF CURRENT RESEARCHES. —

ZOOLOGY.

A. VERTEBRATA: —Embryology, Pee and General.

a. Embryology.

M‘Cuvrn, C. F. W—Primitive Segmentation of Vertebrate Nan fs
Ziecier, H. H,—Origin of Blood of. Vertebrates .. ae.
WauppyEer, W.—Placenta of Inwus nemestrinus ..
TornuR, Sir WitLiam—Placentation of the Dugong ..
Herneriorvs, G. eae of Placenta in Dog

eo

Suorz, T.. W., & J. W. Pickrrtnc—Pro-amnion and Amntin Mm the Chick

Morean, T: H., & BE. C. Appirucartu—Fate of Amphibian Pips
Massart, J.— Penetration of Spermatozoa into Ova of Frog
Granvis, V.—Spermatogenesis during Inanition .. | ..

oe

¢e ae oe

B, Histology.

ee 7 a eo » oe

eo

ee

Barsacct, O.—Phenomena of Indirect Nuclear Fission in Investing Hpithelia

DeMARBAIx, H.— Division and Degeneration of Giant-cells of Medulla or Bone

es

Haswewi, W. A.— Comparative Study of Striated Muscle ..
Friix, W.—Growth of Transversely Striated Muscle .. ae
Van Der Srricut, O.— Fundamental Structure of Osseous Whee si
Biscuit, O,—Structure of Protoplasm Mae

Y General.

CrarKke, J.—Protoplasmic Movements and their Relation to Obggen: Pressuré

Lozs, J.—Orientation of Animals towards Light..
» » Orientation of Animals towards Gravity <9

B, INVERTEBRATA.

M‘Cor—Zooloqy of Victoria
Srun~mann, A. F.—Fr esh-water Fauna ‘of East A frica

Mollusca.
Locarp, A. ee Malacology ..
PELSENEER, Pi— Innervation of Osphradium ‘of Mollusca

oo on

*

a, Cephalopoda. :
Wartase, S.—New Phenomenon of Cleavage in Ovum of Cophalopods ‘f

8, Pteropoda.

Peck, J. 1.—Anatomy and Histology of Cymbuliopsis calceola ..
PELSENEER, eae Position of Desmopterus papilio

y- Gastropoda.

DatL, W, H. baa and Scaphopoda of the West peal Seas
Bateson, W.—Variations of Cardium edule ae

Dexots, R.—Luminous Phenomena in Pholas dactylus ; :
GaARstanc, W.—Nudibranchiate Mollusca of pan’: Sound

© Fou, H —Microscopic Anatomy of Dentalium

ef

ee ae eo” oe

(8)

5. Lamellibranchiata.

M‘Axrine, D.—Movements of Bivalve Mollusca .. 6. 65 ce ae as
Dau, W. H.—Abranchiate Lamellibranchiata BAe eiiy des et a RN
‘Molluscoida,
a. Tunicata,
Morean, T. H.—Origin of Test-cells of Ascidians 4... skeen ees
8B. Bryozoa.
Brnuam, W. B.~—Anatomy of Phoronis australis Peery Macey egy ON Te Fol BC ew
_ Arthropoda.
BepparD, F. E.—Origin of Malpighian Tubules in Arthropoda...»
Carrikre, J.— Hye of Decapod Crustaceans and Arachnids .. .. ..
a. Insecta.
Wasmann, E.—Function of Palps in Insects ate Be Sheen aera

- Haagen, H. A.—Double Plexus of Nervures in Insects’ Wing Boa ve
Graber, V.—Structure and Piaeneite Significance. of Himbryonio 2 ‘Abdominal

Appendages in Insects .. ace oe
Fioxrert, C.—Markings of Lepidoptera tn the Genus Or nithoptera Me Waa
Puiarner, G.—Spermatogenesis in Lepidoptera .. Wayheee

Sxertcuiy, 8S. B. J,—Habits of certain Borneo Butterflies ity eee

Gitson, G.—Odoriferous Glands of Blaps mortisaga .. .

WHEELER, W. <4 —Glandular Structure on Abdomen gf Embryos of Hemiptera
ee ie .— Life-history of Chermes

MinGazzini, P.— Hypodermis of Periplaneta nd

Grirrirus, A. B.—Malpighian Tubules of Libellula depressa

y. Prototracheata,
Sarnt-Remy, G.—Brain of Pertpatus .. 2. ke a

6. Arachnida.
Guirrrius, A. B., & A. Jounstone—Malpighian Tubes and “ Hepanie cole ” of

Araneina .. agent “a
_ Grrop, P.—Anatomy of Ataw ypstlophorus and A. Bonwé $3 Ae canary
Louman, H:—Halacaridz cs bE neces

Warasz, S.—Structure and Development of Eye of Limulus Sen ee

«. Crustacea.

Bartrson, W.—Senses and Habits of Crustacea... ., MO Waa er Pee. ee

We.pon, W. F. R.—Funetton of Spines of Crustacean Zowe Oe Sera
Celom and Nephridia of Palzmon serratus... «> ..

GraRD, A. —Phosphorescent Infection of Talitrus and other Orustacea .. 1. vs

Bouvier, L.— Nervous System of Decapod: Crustaceas os -.0 pe OS ae

Grirrirus, A, B.— Liver” of Carcinus menas.. 660 ea ee ae

FarNANI, J.—Genital Organs of Thelyphonus .. .. 4. aes

Broon, G.—Lucifer-like Decapod Larva... tt a inert

Brooxs, W. KK. & F. A: Heenrox—Life-history of Stenopus Peat RUNES 6

Brooxr, G., & W. E. HoyLe—Metamorphosis oh: hho: Euphauside ia

Cuun, C. — Male of Phronima sedentaria .. Gaeearcine ptt ee

Bourne, G. C.—Pelagic Copepoda of Plymouth .. :
List, J. H.— Female Generative Organs and Oogenesis in Parasitic Copepoda

Vermes.
Mavpas—Agamic Multiplication of Lower Metazoa .. .. on
$ a, Annelida,
Saint-Loup, BR: —Polyodontes MANDA COSU Be LO SEO og SCA Sc a NR ey dE
Bepparp, EF. E.— Notes on Oligocheta .. —. RENAE ik ae
4 +5 Oligochztous Fauna of New Zealand =e

Anatomy and Histology of Phreoryctes i
Ph ATNER, G:—Polar Body 'y Formation in Aulastomum

PAGE

739
740

740

740

742
742

742
742

143
743
743
744
744
745
745
745
745

745

746
746
747
747

748
748
749
749
750
750
750
751
752
752
753
753
753

753

754
754
754
755
755

(4)

B. Nemathelminthes.

Vitior; A.— —Ovary and Oogenesis of Gordius :
Montez, R. ik -history-of a Free Nematode .,

Ramer, A —Filaria medinensts in Animals
Linstow, O. v.—Pseudalius alatus : +.
ZscHoRKE, F .—Spiroptera alata, a new Nematode found in Rhea americana ..

GIBIER, P.— Vitality of Trichinz

7: a Sete ie

SeKera, H.—Fresh-water Turbellaria
Boumic, L.—Microstoma papillosum
Mowricetur, F. S.—WNotes on Entozoa ..
Sonsino—Helminthological Notices...
Braun, M.—Tristomum elongatum..

ee

5. Incertze Seais.

Harmer, 8. F.—Anatomy of Duels
Hopson, C. T.—Rotifera..

Tel dees

‘Semon, R. Tip aonees within the Hchinoderm- Shee
Epwe ~ C. L.—Embryology of Muelleriu Agassizit ..
Joun, G.—Boring Sea-Urechins
Grirrirns, A. B., & A. J onnstonn—Saceular Diverticula Be Asteroidea
Ives, J. E —New Ophiurids . j

GacWuterata,
Curn’s (C:) Coelenterata .. Ba ,
Witson, H. V.—Occasional Presence of ¢ a Mouth ‘and: Anus. 0 Actinozoa
Fiscuer, P.— Arrangement of Tentacles in Cerianthus Bee a sr as
Ortuann, A .—Madrepore Corals from Ceylon 2. 6. an wt ee et
Dixon, G. Y., & A. F,—Bunodes and Tealia ar
McMvrricu, J.P. — Kdwardsia-Stage in Free-swimming Embryos of | a Fesaninan
Broo, G. —New Type of Dimorphism found in Antipatharia .. ..

Ciavus, C.—Organization and Phylogeny of Siphonophora .. :

Porifera.

LENDENFELD, R. v.—Monograph ef Horny Sponges... «2 se ee te se we
Maas, O.—Metamorphosis of Larva of Spongilla.. 3

Protozoa.
Bbrscu.i's Protozoa .. . EF
Romanes, G. J. — Psychology of Protozoa
Grirritss, A. B.—Method of Demonstrating Presenee eof Urie Acid in Contractile:

Vacuoles of lower Organisms 5 Z Bee

Famintzin, A:—Symbtiosis of Algz and Animals -. ie geste oe
ScuEWwrAKorr, W.—Holotrichous Infusoria .. 1.0 fe te wee
Garoin, A. G. —Pigment of Euglena ee Sf
KCUNSTLER, J.—New Proteromonas.. —. f
Smumons, W. J.—Podophrya from Caleutta ..
Dreyer, F.—Structure of Rhizopod Shells.
Mosivs, K.—Rhizopod-Fauna of Bay of Kiel
Astart, A.—Nuclearia delicatula ..
SCHLUMBERGER, C.—Reproduction of Foraminifera
ScHUBERG, A.—Grassia ranarum Be Cay

BOTANY.

A. GENERAL, including the Anatomy and Physiology
of the Phanerogamia.

a. Anatomy.

(1) Cell-structure and Protoplasm.
Nou, F.—Structure of the Cell .. UCL, ARR Fp cee omar
Korpren, O. W.—Nucleus in Dormant Seeds
GuicnarD, L.—Pollen of the Cycadex ..

772
772
772

eros)

(2) Other Cell-contents (including Secretions).
Arcancrtt, G.— Composition of Chlorophyll
REINITzER, F'.—Composition of Tannin., 16> +e ee ee teen wt
Ropier, Be Seren ais eee Sire oe
NADELMANN, H.—Mucilage in the Endosperm of “Leguininose Berra Plater pe py
Prrorra, R.—Starch in the Epiderm .. Sie gnee want bales ean Os akin agri
JOHANNSEN, W.—Gluten in the Grain of Corn aM ALE iae yhewe

AcQua, C.- Formation of Calcium oxalate in Plants ..
Werumer, C.—Calcium oxalate in Plants

Bionpet, R.— Perfume of the Rose

Crepin, F.—QOdour of the Glands in Rosa

(8) Structure of Tissues.

Groom, P.—LEaticiferous Tubes :
Renv.eE, A. B—Vesicular Vessels of the Onion ..
Marrrroxo, QO.. & L. Buscationi—Intercellular Spaces é in the Tegument of the

Seed of Papilionacer .. *
sd eda ye Lilet Pag Appar atus in the Stem of Savifragacez .. "Gaia
Gyentscu, F.—Radial Union of Vessels and WORE NS
Kny, L.— Formation of Healing Periderm
Wrexer, A Sig Shite and Development of Libriform Fibres ..

Scamipt, E Ape ae Medullary Rays bien Breas
Macartiti, L.— Foliar Medullary Bundles of Ficus Ma
(4) Structure of Organs.
Derrino, F.—Ovuliferous Scales of Conifer — .. se ae we ees
Hatstep, B. D.—Sensitive Stamens in Composite Ge SL a ea

Danre., L.—Bracteoles of the Involucre in the Cy ynarocephalee ..
Meruan, T.—Secund Inflorescence Ph Sah pen atopepSer ec

Crerin, F.— Ovaries and Achenes of Pachhee ee oe ee
Rosz, J. N.—Achenes of Coreopsis .. iets ier re

Drnaier, H:—Floating-orqans abate a crea nceas ties RU ae Lani ese eat al Oh la peed dg
Bower, F. O.—Pitcher of Nepenthes .. eh aye Mane oneal Wels
MAcrarbAne, J. M.—Pitchered Tasceleporous: Plants. ean Sees See
Meeuan, T.— Homology of Stipules edt aka toa os saad oe
GorBEeL, K.—Stem and Leaf of Utricularia . sp Ra

Vines, §. H.—Opening and. Closing of Stomates ..
Merxer, P.—Oolleters and Glands of Gunnera

Vocutine, H.—Abnormal Formation of Rhizome..
Witson, W. P.— Aerating Roots Shi de

B. Physiology.

(1) Reproduction and Germination.

ROBERTSON, C.—Floweis and Insects 0 be ne ne et
Merenan, T.—Dimorphism of Polygonum... 6s be ene ee
HILDEBRAND, F'.—Properties of Hybrids .. .. Fale iee Pet ae ees
(2) Nutrition and Growth (including Movements of 2 Fiaide).
Miiurr, T.—Influence of “ Ringing” on Growth
HeuirizceL, H., & H. Winitrarta—Obtaining of Nitrogen Le " @raminex e and
Leguminosce q : Se
FRANK, B.—Power of plants to absorb Nitrogen from theip es ce eve ae
Kroricnt, P.—Movements of Gases in Plants ss 44 ae oe wee ee

Wortmann, J.—Curvature of Growing Organs

(4) Chemical Changes (including Respiration and Fermentation).
PALLADIN, W.—Influence of Oxygen in the Decomposition of Albuminoids

SAPOSCHNIKOFF, W.—Formation of Starch out of Sugar eS
Ducitaux & Apametz—Alcoholic Fermentation of Milk .. .. 4. ss
y- General.

JUMELLE, H.—Development of Annual Plants
Curistiz, J.—LEsparto-grass

PAGE

773

773
773
773
713
774

775
779

B. CRYPTOGAMIA.
Pror, DE Bary’s Microscopical Slides

Cryptogamia Vascularia..

Bexaserr, W.—Antherozoids of Vascular Cryptograms <i. eels ty ee .
MEuNIER—Sporocarp of Pilularia .. ae eevee :
Sasion, Lecterc pu—Hndoderm of the ‘Stem of Selaginellacee Peasy ie
TrecuL, A.—Root of the Filiciner.. .. ras .
Alge.
Tont, G. B. —Phyllactidium, Phycopeltis, and nara fap beg ee eer
ATWELL, C. B.—Conjugation of Apnea wESS gay Sie Dae Mata ete es ce
Ryper, J. A.—Volvox minor .. sevice oh Piken Ove onl laa ele ae
Fungi.

Cosrantin, J., & Rutnanp—Blastomyces .. ss we ce te as
THOMAS, F.—Synchytrium alpinum Laity tevin ubrate oo piace clan ene eaetges

BREFELD, O.—Ustilaginer — ... kg esate va tal ee ae

Linpt— Pathogenic Fungus from ‘the Eman ‘Hor oS Soho gs Sear
Bonnet, H.—Parasitism of the Trufie .. 1. 2. sews rE
TuBEur, C. v.— Fungi parasitic on Trees oe

Tutmnn, F. v.—Fungi parasitic on Rice.

Costantin, J.—LHchinobotryum and Stysanus een cee Nees
BeEr.ese, A. N.—Prolification in the Hyphomycetes ean Dapy Dalb

is Laboulbeniacer .. Ses

Vovisrers, J.—Contemporaneous action of different hinds of Suiechiiromyees. .

Barciay, A,—Himalayan Uredinee _.. Escola suey tee

LAGEREEM, G. v.—Rostrupia, a new genus of Ur os ue che ee cae pee

Boutey, H. L.—Subepidermal Rusts .. —. RSS ne tH cae ioe ms

THAXTER, R.—Cultures of Gymnosporangium pd RET e PBS Behe ae atin cs
CunnincHam, D, D.—Ravenelia 1... clk teehee ee ae OE US Ree OC EN
Barotay, A.—Cxoma Smilacinis «1.6 se vee men

‘SapiLey, A. E.—WMacrosporium ‘parasiticum ni Leb Nea we say Go ia NR aes
Smitu, EH. F.—Peach-Yellow .. .. ee Be Sea Wg es Peat
Fayop, V.—Boletopsis, a new Genus of Hymenomycetes Teh Ai ree

Fuiton, T. W.—Dispersion of the Spores of Fungi by Insects .. .. 4. ss

Mycetozoa.

ZorrF,
- Protophyta.

a, Schizophycez.

Correns, C.—Growth of the Cell-wall by Intussusception in some 1 Behizophyees is

ImnAvser, L.—Prasiola .. «. seen ete stein

Bornet, E.—Heterocystous Nostocaceze . eo) ite Us sae wr ck nao aan Lara Cap Paiag

Miter, O.—Movements of Diatoms’ 1. we ae
», Ausxospore of Terpsinoé. .. fae gbe AV eb eeneie Sd Minton pas
WEED, W. H.—Diatom-beds of the Yellowstone .. .. -. es esi ea eabas

B. Schizomycetes.

GairritHs, A. B.—WMicro-organisms and their Destruction
Lupwic—Micro-organism found.in the mucous flux of Trees
MeETScHNIKOFF—Pleomorphism of Bacteria ..

Aui-Congen, C. H.—Movements of Micrococet, -. -.. ey su ne ewe

Cuavveau, A.—Variability of Bacillus anthracis... 1s te in
Covurmont, J.—New Bovine Tubercle Bacillus

VouItLemin, P.—Relation of the Bacilli of the Aleppo Pi Pine io the living tissues aioe

CunnincHam, D. D.—Cholera Bacillus...
Roux, EH. —Preventive Inoculations ..
FREUDENREICH, H. pe—Antagonism. of the Bacillus of ‘Blue Pus and Anthrax

W.—Oolowring-matters of Mycetozon :. 1. sx. es at as se oie

7.

798 tae

Coe
MICROSCOPY.

a. Instruments, Accessories, &c.

(1) Stands.

Anperson’s (R. J.) “Panoramic Arrangement for the oh cca Me Cig: a.
NELSoN-CURTIES Microscope (Large Model) (Fig. 98) . Fe hTs
EpinsurGnu Students’ Microscope (Figs. 99 and 100) .. 2
Lxacu’s (W.) Improved Lantern Microscope (Figs. 101- 103) if

(2) Eye-pieces and Objectives.
1/10 in. Apochromatic Objective of NA. 1°63 eee ee ae as

(5) Microscopical Optics and Manipulation.

Lowne, B. T., & E. M. Netson—Diffraction Theory (Figs. 104-107)... 4. «.
Suirz, T. F.—Ultimate Structure of the Pleurosigma Valve (Figs. 108 and 109) .,
Leroy, C. J. A.— Disturbances of Vision consequent on Microscopic Observations
DineLor, L.—Amplifying Power of the Microscope (Figs. 110-112).. .

(6) "Miscellaneous.

Rocers, W. A.—The late Chas. Fasoldt =e
Scorrisy Microscopical Society .. aa Ty

B. Technique.

: (2) Preparing Objects.
Sorerr, B.—Demonstrating Mitosis in Mammalia... ..

Dusors, F.—Mounting Fish-scales .. 21 su veo

Bepor, M.—Preserving Marine Animals CE Ia> IW RP ara k Day eer
Faxae-Domnreur—LHzxamination of Protozoa ie Te eee taget ip opr eee EN Ley eit
Scuewianorr, W.—Investigation of Infusoria’ .. Bat RUNS pore ae, aay Selb
Harerrr, C. W.—Mounting Infusoria .. Wig RE GE oie, & PRES tare
Brown, ‘A. P.—Medium for mounting Starches and Pollens ery a aoa
‘Git, C. Havcutron—Preparing Diatoms .. pixie ine Miao tte ek

Fayop, F.— New Application of Photography to Botany Reon
Astiuy, Wricht—Production and Preservation of Saccharine Crystals ..

(3) Cutting, including aap mar and Microtomes.
Pout, A.—Imbedding in Glycerin Soap... 0, eee dee a ak
Wess, T. L.—Dextrin Mucilage for Inbedding Sige eee CHa) ae ee ee
Winxs’ (G.) Improved Microtome .. ., Mier Sahay SEM ods et ep eRe Cg whee s
Hoveu, R. B.—Thin Sections of Timbers. ey a ke

(4) Staining and Sra ah
Sanretice, F.—Todized Hematoxylin. .. Dante
TRENKMANN—Staining the Flagella of Spirilla and Bacilli e
_ Docier, A. 8.—Impregnating Tissues by means of Meshalen lie ¢s
Fiot—Impregnation in Black of Tissues .. +» Seat see te

(5) Mounting, including Slides, Preservative Fluids, &c.
GALLEMAERTS—Method for fixing Serial Sections to the Slide... a
Dionisio, L—Apparatus for fixing down Series of Sections (Fig. 113) ¥
Bonpurant, E. D.—Section-fixing..

Dawitz, J.—Slide-rest for the Manipulation ‘of Serial Sections Og, a4)
Moxr.iannp, H.—Mounting “selected” Diatoms .. .. ee a
CuapMan, FE. T.—Carbolic Acid in Mounting .. 5 «ss :

(6) Miscellaneous.
Beurens, W. rages for Isolating Objects (Fig. 115)...

Forst2rter, E.—New Method for the Bacteriological Examination of Air
(Figs. 116 and 117)

Hovenven, F'.— Examining thin Films of Waiter i020 ee ray are #3

Kurzs_ (W.) Transparent Microscopical Plates .. 1 es ee te ke

PROCEEDINGS OF THE SooIETY Pam er gN Wek a gd ASL oy ase KC cl a

799
800
802
803

805

806
812
817
818

829
830

831

Numerical ||

Aperture.
(n sin u= a.)

1°52
1°51
1:50
1:49

0:82

APERTURE TABLE. a eee

Corresponding Angle (2 w) for Limit of Resolving Power, in Lines to an Inch. ; “FT Pene-
Monochromatic trating
Air Water | Homogenens White Light. | (Blue) Light. | Photography. SNe
|) (v= 1°00). | (2 =1°33)..) (= 1°52). X Tine E.) #4) Tine F) ve einen ()
180° 0’ 146,543 188,845 193,037 ‘658
166° 51’ 145,579 157,800 191,767 4° 662
| 161° 23’ 144,615 156,755 190,497 | - “667
157°. 12’ 143,651 155,710 189,227 2 » 671
153° 39’ 142,687 154,665 187,957 | 7676
150° 32’ 141,723 153,620 186,687 4- *680
147° 42’ 140,759 152,575 185,417 ia 685,
145° 6! 189,795 151,530 184,147 $ “690
142° 39’ 138, 830 150,485 182,877 of “694
140° 22° 137,866 149,440 181,607 “04, “699
188° 12’ 136,902 148,395 180,337 ‘ ~7104
136° 8’ | 135,938 147,350 179, 067. f -709 -
134° 10’ | 134,974 146,305 177,797 . 74
-132° 16’ # 134,010. | 145.260 176,527 ‘ “719
136° 26’ 133,046 144,215 175, 257 ; ©2725
128° 40’ 132,082 143,170 173,987 “729
126° 58’ 131,118 | 142,125 172,717 : +735
125° 18’ | 130,154 141,080 171,447 "825 741
a 123° 40’ | 129,189 140,035 170,177 “TI6 *746
180° 0’ | 122° 6! 4 128,225 138,989 168,907 1-7/6 Shoe
165° 56’ | 120° 33’ § 127,261 137, 944 167, 637 i ‘ *758
155° 38’ | 117° 35’ f 1255333 135,854 165, 097 za ~7169
148° 42’ | 114° 44" 9} 123,405 133,764 162,557 ; : “781
ar 142° 39’ | 111° 59’ § 121,477 131,674 160,017 sg le “794
of 137° 36’ -| 109° 20’ {- 119,548 129,584 157,477 : f. °806
133° 4’ | 106° 45’ 117,620 | 127,494 154,937 ‘ “fF +820
128° 55’ | 104° 15’ # 115,692 125,404 | 102,397 ae +833.
125°. 3’ | 101° 50” | 113,764 123,314 149,857. | 1:38 | 847
121° 26’ 99° 29’ f 111,835 121,224 147,317 | 1:346 *862
118° 0’ 97° 11’ 9 109,907 119,132 4 ae Tr oe g heel oA
114°. 44’ 94° 55’ 4 107,979 117,044 1492387) Al: 4 7893
111° 36’ 92° 43" | 106,051 114,954 139,698 “2 : *909
108° 36’ 90° 34’ f 104,123 112, 864 137,158 “hs 926
105° 42’ 88° 27’ f 102,195 110,774 134,618 el _ 19438
102° 53’ 86°21’ # 100,266 108, 684 132,078 3 962

SS 100° 10’ | $4° 18° 98,338 | 106,593 | 129,538 . -980
180° 0’ | 97° 31. | 82°17 | 96,410 | 104,503 | 126,998 }- -000
157° 2’ | 94° 56’ | 80° 17° 94.482 | 102,413 | 124,458 “020
147° 29' | 92° 24’ | 78° 20" 92.554 | 100,323 | 121,918 “042
140° 6’ | 89° 56 | 76° 24’ | 90,625 98,233. | 119,378 “064
133° 51’ | 87°32" | 74° 30! 88,697 96,143 |. 116,838 “087
128° 19’ | 85° 10’ | 72° 36' | 86,769 94,053 | 114,298 “111
123° 17" | 82° 51’ | 70° 44’ 84,841 91,963 | 111,758 -136

118° 38’ | 80° 34" | 68° 54’ 82,913 89,873 | 109,218 “163 -
114° 17’ | 78° 20! | 67° 6' | 80,984 87,788 | 106,678 -190

110° 10’ | 76° 8’ | 65° 18! 79,056 85,693 | 104,138 “290 ~
106° 16 | 73° 58’ |. 68° 31 | 77,128 83,603 | 101,598
102° 31’ | 71° 49’ | 61° 45’ | . 75,200 81,513 99,058 -
98° 56’ | 69°42’ | 60°. 0’ | 73,272 79,423 96,518

95° 98’ | 67° 87 | 58° 16’ | 71,343 17,338 93,979
99° 6! | 65° 32’ | 56° 32’ 69,415 75,942 | 91,489

88° 51’ 63° 31’ 942 50’ 67,487 73,102 88, 899 429
85° 47’ 61° 30’ 03° =—9! 65,559 71,062 86,309 471
82° 36’ 59° 30’ D1° 28’ | 63,631 68,972 83,819 515.
719° 36! 57° 31’ 49° 48’ 61,702 66,882 81,279 562
76° 38’ 50° 34! 48° 9’ f 59,774 64,792 78,739 613
73° 44! 53° 38’ 46° 30’ 57,846 62,702 76,199 667
70° 54’ D1° 42’ 44° 51’ | 955,918 60,612 73,699 724

68° 6’ 49° 48’ 45° 14’ 93,990 58,522 71,119
65° 22! 47°. 54 Co hears 02,061 56,432 68,579 -

Pa tt et et ee
(St)
—
jor)

62° 40’ re Cobia 40° 0’ 50,133 54,342 66,039 923
60° 0’ 44° 10’ 38° 24’ . 48,205 52, 252 63,499 : 4 2:000
58° 30’ 39° 33’ 34° 27’ 43 385 47,026 57,149 fF * 2°222
Aina Y 35° (0! 30° 31’ 38,564 41,801 50,799 : - 4 2°500
40° 58’ 30° 30’ 26° 38’ 33,744 36,076 44,449 +123. 2°857_
34° 56’ 26° 4’ 22° 46° 28,925 31,351 38,099 ‘ 37333
28° 58’ 21° 40' 18° 56’ 24,103 26,126 31,749 : 4°000°
23° 4! i bed Wolf 10937’ 19,282 20,901 25,400 ; 5-000
172% 14’ 12° 58’ 112 19% 14,462 15,676 19,050 : 6°667
112,29" 8° 38’ 7? 84 9,641 10,450 12,700 : 10:000—
5° 44’ 4° 18’ 3° 46’ 4,821 5,229 6,390 :005 420°000 ~

COMPARISON OF THE FAHRENHEIT AND CENTIGRADE THERMOMETERS.

Fahr. Centigr. Fahr, Centigr. Fahr Centigr Fahr, Centigr. Fahr. Centigr,
es Rea Vales oe ied arate teks a Se Bonn
° ° ° ° ° ° ° ° °
212 100 158 70 104 40 10 - 4 - 20
210°2 99 156+2 69 102°2 39 2 9 - 5:8 =21
210 98+ 156 68-89 102 38°89 8:89} - 6 - 21°11
208°4 98 154°4 68 100°4 38 “4 8 - 7°6 - 22
208 97° 154 67°78 100 37°78 7778) - 8 — »22°22
206°6 97 152°6 67 98°6 37 “6 Ws — 94 - 23
206 96 152 66°67 98 | . 36°67 6°67 | - 10 — 23°33
204°8 96 150°8 66 96°8 36 2°8 6 - 11:2 | -24
204 95 150 65°56 96 35°56 5°56 7 - 12, — 24°44
203 95 149 65 95 35 5 - 13 - 25
202 94° 148 64°44 94 34°44 4-44] - 14 — 25°56
201.*+2 94 147°2 64 93°2 34 22 4 — 14°8 - 26
200 93° 146 63°33 92 33°33 3°33} - 16 = 26°67
199°4 93 145°4 63 91°4 33 “4 3 — 16°6 - 27
198 92° 144 62°22 90 32°22 2:22 -~18 = 27°78
197°6 92 143°6 62 89°6 32 "6 2 - 184 | = 28
196 91 142 61-11 88 31°11 1-11 |} -— 20 —, 28°89
195°8 91 141°8 61 87°8 ol 3°8 1 — 20°2 - 29
194 90 140 60 86 30 O =~ 22 - 30
192°2 89 138°2 59 84:2 29 2 - 1 - 23°8 - 31
192 88: 138 58°89 84 28°89 - lll} -24 = 3111
190°4 88 13674 58 82°4 28 +4 - 2 - 25:6 | —-32
190 87° 136 57°78 82 27°78 — 2:22) -26 — 32°22
188°6 87 134°6 57 80°6 27 6 - 3 — 2774.| = 33
188 86 134 56°67 80 26°67 — 3:33] - 28 — 33°33
186°8 86 132°8 56 78°8 26 8 - 4 — 29°2 |= 34
186 85 132 55°56 78 25°56 - 4-444 - 30 — 34°44
185 85 131 55 17 25 - 5 = 31 - 35
184 84- 130 54:44 76 24°44 — 5°56} - 32 — 35°56
183+2 84 129+2 54 75*2 24 2 - 6 — 32°8 | - 36
182 83° 128 53°33 74 23°33 — 6°674 -— 34 — 36°67
181-4 83 127°4 53 73°4 23 4 Cae f — 34°6 | - 37
180 82 126 52°22 72 22°22 - 7:78) - 36 - 37°78
179°6 82 125-6 52 71:6 22 “6 - 8 —- 36°4.| - 38
178 81 124 5111 70 21°11 - 8°89} -38 — 38°89
177°8 81 123°8 51 69°8 21 8 - 9 - 38:2 | -39
176 80 122 50 68:2 20 - 10 - 40 - 40
174:2 79 120-2 49 66 19 Pe = 11 — 41°80} - 41
174 78: 120 48°89 66:4 18°89 - ll'll} -42 = Alot
172-4 78 118°4 48 64 18 i 4 -12 — 43°60} - 42
172 7 118 47°78 64°6 17°78 — 12:22] - 44 — 42°22
170°6 17 116°6 47 62 17 6 -13 — 45°40) — 43
170 76° 116 46°67 62°8 16°67 — 13°33 } — 46 — 43°33
168°8 76 114°8 46 60 16 8 -14 — 47:20| - 44
168 75° 114 - 45°56 60 15°56 — 14-44] - 48 — 44°44
167 75 113 45 59 15 5 -15 - 49 - 45
166 74° 112 44°44 58 14°44 4 — 15°56} -— 50 — 45°56
165:°2 74 1-2 44 5772 14 3°2 - 16 — 50-80| - 46
-164 73°3: 110 43°33 56 13°33 2, = 16°67} —-52 | — 46°67
1634 73 109°4 43 55°4 13 1*4 - 17 — 52°60) - 47
162 72° 108 42°22 54 12°22 oO — 17°78} -54 — 47°78
161°6 72 107-6 42 53°6 12 - 0-4 -18 - 54°40; - 48
160 cae 106 41-11 52 ll‘ll. | -2 — 18:89} -56 = 48°89
159-8 71 105°8 41 51°8 11 — 2:2 -19 — 56°20| — 49
; -58 | -50
FAHRENHEIT

AQ 30 20 ae o 0 id 30 40 50 60 10 80 ae eae 150 160 170 180 190 200.212

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110 | -4; inch 95 5 0 0 150 240 | 450 600 750
111 i ATIC ee ora) are 75 310 0 | 200 | 320 600 | 800 |. 1000
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Lbs o7 Dinehe ea ci 290% | 5 -0 O| 400 | 640 | 1200 | 1600 | - 2000
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Revised Catalogue sent on application to
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JOURNAL

OF THE

ROYAL MICROSCOPICAL SOCIETY.

DECEMBER 1889.

TRANSACTIONS OF THE SOCIETY.

XI.—On the Effect of Illumination by means of
Wide-angled Cones of Light.

By Prof. E. Assz, Hon. F.R.M.S.
(Read 9th October, 1889.)

Tue diffraction theory leads to the following conclusions in regard to
the mode of illumination in question.

(1) A wide-angled illuminating cone must be considered as com-
posed of a multitude of (infinitely) narrow pencils, which have very
different directions of incidence upon the object—from perpendicular
incidence (the axial pencil) to a certain degree of obliquity, with all
intermediate directions in gradual change.

(2) Provided the structure under observation admits of a per-
ceptible diffraction-effect, every single (i.e. infinitely narrow) beam
of incident light is “split-up” in its transmission through the
structure, into the “ diffraction-pencil” (or “fan”) which is peculiar to
the structure ; and gives rise to a certain diffraction-spectrum at the
back of the objective.

According as this elementary diffraction-fan of every incident ray
has more or less angular extension, and according as the incident ray,
to which it belongs, is more or less oblique—both these points con-
sidered with regard to the aperture of the objective—a smaller or
greater part of such an elementary diffraction-spectrum is admitted to
the objective, and utilized for the formation of the image.

(8) In the case of a sufficiently wide-angled illuminating cone
(at all events, when the incident light fills the whole aperture) the
multitude of elementary diffraction-pencils, corresponding to the
multitude of elementary incident rays, mingle together at the back of
the preparation—and the diffraction-spectra at the back of the
objective—overlapping one another to such an extent, that nothing
else but white light, filling out the whole aperture, can be ohserved.

Nevertheless these various elementary diffraction-pencils, mingled
together within the objective, produce images of the object quite
separately ; every single elementary pencil gives rise to its own

1889. 3 E

722 Transactions of the Society.

image; the rays of different elementary pencils being unable to
co-operate.

For the projection of an image is based on the re-collection (into
one point) of an undulatory motion which is derived from one
luminous point (one element of the original source of light). Rays
which originate from different luminous centres (as is the case with
diffracted rays appertaining to the diffraction-pencils of different
incident beams) are incapable of interfermg—the undulatory motions
of those rays are quite independent of one another, “ incoherent” ;
they cannot add their undulations according to the interference
principle; but can add only their “ vis viva,” i.e. the intensity of
illumination.

For explanation: In fig. 96 let (a, a, a, ... ) and

(b, Bs, Bo... ) be the cross sections of the diffraction-pencils of
any two different incident rays a, b, a, Bi, a2, Bz... denoting
Fic. 96.

corresponding diffracted rays within these pencils, or let the same be
a representation of any two elementary spectra at the back of the
objective, isolated (mentally) from the whole multituce: then only the
rays from the group @, a, a2 . . . act together by way of interference
at the plane where the image is projected —and project such an image ;—
and also the rays emanating from b, 8,, 8... . im the same way;
but no ray of the first pencil unites with any one of the others.

Consequently, the image which is obtained by means of the wide
illuminating cone is a mere superposition of a multitude of elementary
images, produced quite separately by the various narrow beams; and
this superposition consists of a mere addition of the quantities of
light, which the various elementary images obtain at one point of the
field, and does not involve an addition of the amplitudes of oscillatory
motions according to the interference-principle (as is the case in the
formation of every single elementary image).

(4) The elementary images produced by the various narrow

On the Effect of Illumination, &e. By Prof. BE. Abbe. 723

beams of which a wide incident cone is composed, are dissimilar
images in general ; and this for two reasons: —

(i.) Provided the diffraction effect of the structure is not confined
to very small angles, the admission to the objective of pencils of
different obliquity (i.e. pencils which result from incident rays of
different obliquity) is different—or a different part of every elementary
diffraction-fan is lost. That belonging to an axial incident beam is
admitted in its central position, and a peripheral portion only is lost ;
that which belongs to an oblique ray is stopped off up to a full half,
one from the left hand, another from the right. As the admission of
different parts of the total diffraction pencils of a structure makes the
images always different (at least in the more minute features), their
different obliquity of incidence alone would be sufficient to make the
resulting image a mixture of different (and, in general, differently
dissimilar) images; and this will be so, even in the cases where the
diffraction-effect itself (not considered the different mode of partial
admission to the aperture) is the same for an axial and an oblique
incident ray.

(ii.) But this diffraction effect by itself is not the same for rays
of different obliquity, except with such structures as act solely by
means of absorption of light (total or elective), i.e. with such struc-
tures the detail of which shows simply a difference of transparency
of the elements. In all structures, the elements of which show at the
same time difference of refraction (or of density), rays of different
obliquity are subjected to different amounts of retardation during the
transmission ; and owing to this, the diffraction-pencils arising from
incident rays of different obliquity are of unequal constitution. ‘Theory
and experiment show that the images, projected by means of two
beams of different obliquity of a structure of that kind, may be very
widely dissimilar, in such a degree that in one partial (elementary)
image there is a maximum of light at the same point of the field
where the other has a minimum, or darkness. ‘The mixture of a
variety of elementary images of that kind must, consequently, produce
more or less confusion, or even total suppression of structural detail.

This is practically made use of with great success in the method
of R. Koch of Berlin, in the observation of tinted preparations. He
recommended, twelve years ago, the use of a wide-angled cone of light,
in order to suppress in the image of a preparation all the elements
which have no colour, and to enhance in that manner the image of
the coloured elements. The latter ones act merely by absorption,
and therefore give rise to equal diffraction spectra for rays of different
obliquities ; the former ones (the histological tissues, uncoloured) act
merely by means of different refraction and different retardation of the
transmitted light, and give rise to dissimilar diffraction-pencils and
dissimilar elementary images, the mixture of which is obliteration.

(5) The result of this consideration is:—The resulting image,
produced by means of a broad illuminating beam, is always a mixture
of a multitude of partial images which are more or less different (and

3E 2

724 Transactions of the Society.

dissimilar to the object itself). There is not the least rational ground
—nor any experimental proof—for the expectation that this mixture
should come nearer to a strictly correct projection of the object (be
less dissimilar to the latter) than that image which is projected by
means of a narrow axial illuminating pencil. ‘This latter image has
the most favourable conditions in regard to similarity to the object,
because in its production nothing is lost of the diffraction-pencil but
the peripheral portions (which in most cases are of relatively small
intensity). All the other images with which it is mixed in the
case of a wide-angled cone, are liable to greater dissimilarity, com-
pared to a strictly true image, because they depend upon a more
incomplete admission of the diffracted light. And it is against all
rules of reasoning to assume that a mixture, or superposition, of a
variety of images, all of which are more or less dissimilar to a true
projection, should be less dissimilar than that constituent which is
the least dissimilar one (whatever this one may be).

This conclusion is in no way in contradiction to the fact, that in
many cases a broad illuminating pencil may exhibit indications of
structure which remain occult to a narrow axial one, because oblique
rays are in that respect more effective than the axial ray. ‘The
above discussion turns solely on the approach to perfect similarity of
image and object.

eo

SUMMARY

OF CURRENT RESEARCHES RELATING TO

OO, OG YAN D BOT A NY
(principally Invertebrata and Cryptogamia),

MICROSCOPY, &c.,
INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.’

ZOOLOGY.
A. VERTEBRATA :—Embryology, Histology, and General.
a. Embryology.ft

Primitive Segmentation of Vertebrate Brain.{t—Mr. C. F. W.
M‘Clure considers that the primitive vertebrate brain consisted of a
series of segments, similar to those found in the embryonic spinal cord,
and that the encephalomeres probably held the same relation to the
mesoblastic head-segments as the myelomeres do to their respective
mesomeres, that is, they were intersomitic, the centre of each neuromere
being opposite the space between two somites, and giving off a mixed
nerve from the apex.

The region known as the encephalon is the result of a great differen-
tiation and specialization of the anterior segments of this primitive
structure. That differentiation first began and has been greatest in the
most anterior segments, and this may account for the greater size of the
folds in this region than in the hind-brain, in which less differentiation
has taken place, and which, therefore, conforms more to the vertebrate
type.

Origin of Blood of Vertebrates.s—Dr. H. HE. Ziegler considers that,
phylogenetically, the blood- and lymph-vascular-systems were derived
from the primary ccelom; in ontogeny it may be seen that some of the
first vessels to arise are parts of the primary ccelom, and are gradually
shut off from it. The red blood-corpuscles arise ontogenetically from
solid venous rudiments, and in histological regeneration they similarly
arise from venous capillaries; the red blood-corpuscles, the specifically
respiratory cells, belong both in origin and function to the blood-
vascular-system ; they do not arise from the white corpuscles in the
blood, but have a similar origin with them, insomuch as they are derived
from the histogenetic foundation of all the mesenchymatous tissues.

* The Society are not intended to be denoted by the editorial “ we,” and they do
not hold themselves responsible for the views of the authors of the papers noted,
uor for any claim to novelty or otherwise made by them. The object of this part of
the Journal is to present a summary of the papers as actually published, and to
describe and illustrate Instruments, Apparatus, &c., which are either new or have
not been previously described in this country.

+ This section includes not only papers relating to Embryology properly so called,
but also those dealing with Evolution, Development, and Reproduction, and allied
subjects. t Zool. Anzeig., xii. (1889) pp. 435-8.

§ Ber. Naturf. Gesell. Freiburg, iv. (1889) pp. 171-82.

726 SUMMARY OF CURRENT RESEARCHES RELATING TO

Placenta of Inuus nemestrinus.*—Prof. W. Waldeyer is able to con-
firm Turner’s statement as to the resemblance of the human and simious
placenta ; the spongy layer of Inwus is more like that of Homo than is
that of Macacus. A continuous layer of endothelium is found on the
placental surface of the decidua, and passes on one side into the fetal
villi, and on the other into the maternal placental vessels. The author
shows that the chorion and villi have a double cellular investment, and
that the blood in the intervillous spaces is of a normal character.

Placentation of the Dugong.j —Prof. Sir William Turner bas had
the opportunity of examining the placenta of the Dugong, and has added
to, and in some points corrected, the observations of Harting, who stated
that the placenta was diffused and non-deciduate. The author finds that
should the placenta be non-deciduate, in the sense that the vascular
part of the maternal mucous membrane is not shed, the placenta of the
Dugong gives a new type, one which is both zonary and generally non-
deciduate. The diffused character of the placenta in the specimen
described by Harting was due to its comparatively early stage of deve-
lopment, for the villi had not as yet limited themselves to a definite zonc.

Development of Placenta in Dog.{—Dr. G. Heinricius gives an
account of the growth of the placenta in the dog. The uterine mucous
membrane includes two kinds of tubular glands—superficial crypts and
leng glands reaching to the muscular layer. With the entrance of the
fertilized egg into the uterus, both crypts and long glands elongate and
ramify. This is especially marked in the long glands which expand -
inferiorly into cyst-like spaces. When the foetal ectoderm comes in
contact with the uterine wall, the epithelium of the latter degenerates,
and is apparently absorbed ; foetal villi grow into the connective tissue
septa of the crypt-stratum ; then the epithelial layer of crypts and glands
also degenerates, and the villi come to be surrounded by a syncytium.
The deep stratum of long glands remains unaltered, while the upper
has been modified into the maternal placenta. The villi of the chorion
consist of a gelatinous tissue surrounded by a simple epithelium very
closely adherent to the maternal syncytium. Even when the embryo is
only 1:5 em. in length, there may be seen round each pole a pair of
narrow zones, the “ lateral blood-sinuses.” When the epithelium of the
chorion comes into contact with these, its cells contain blood-corpuscles,
which suggests an important nutritive réle. In the cystic enlargements
of the long glanas, great cellular activity sets in, “uterine milk,” or
plasmic secretion is formed, the villi eventually reach this, and when
they do so, their epithelium becomes adaptively altered in order to
utilize the special nutritive material.

Pro-amnion and Amnion in the Chick.§—Dr. T. W. Shore and
Mr. J. W. Pickering find that there is a diblastic pro-amnion in the
chick, of the same nature as that of mammals. It is bounded at the
sides by the anterior vitelline veins, and so agrees with that of mammals.
The sinus terminalis, unlike that of mammals, is venous. The headfold
is formed by the forward growth of the head over the diblastic pro-
amnion, and not by a folding-off from the blastoderm. The head, tail,

* SB. K. Preuss. Akad. Wiss,, 1889, pp. 697-710.

+ Proc. R. Soc. Edinb., xvi. (1889) pp. 264-5.

~ SB. K. Preuss. Akad. Wiss., 1889, pp. 111-17.

§ Journ. of Anat. and Physiol., xxiv. (1889) pp. 1-21 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 727

and lateral amnion-fold are not formed by a rising up of the blastoderm
round the embryo, but are determined by the growth of the embryo and
its sinking towards the yolk-sac. In ontogeny the amnion owes its
origin to purely mechanical causes, the most important of which are the
weight of the embryo and the resistance of the zona in the presence of
the active forces of growth. The pro-amnion in the chick disappears at
about fifty hours’ incubation, and subsequently contributes to the ventral
part of the head-end of the true amnion and to the wall of the yolk-sac.

Fate of Amphibian Blastopore.*—Mr. T. H. Morgan, with Mr. E. C.
Applegarth, has examined the eggs of Amblystoma punctatum, Rana
halecina, and Bufo lentiginosus. Just before the disappearance of the
hypobiast beneath the epiblast, the blastopore elongates in the direction
of the primitive streak between the medullary folds. The anterior end
of the blastopore is directly continuous with the primitive streak; except
in the region of the blastopore the medullary folds are widely separated,
but in it they almost unite, though at the posterior end a distinct opening
remains visible. In the next stage the neural folds have met everywhere
except at the posterior end, and at this point a cavity is left which seems
from surface-views to remain permanently open. A complete set of
longitudinal sections shows conclusively that, in Amblystoma, part of the
blastopore becomes the anus; from a study of surface-views it was seen
that the elongated blastopore must | ave been in part arched over by the
closing walls of the neural tube. The question of any relation to the
neurenteric canal next suggested itself; some sections were seen in which
the neural tube dips in suddenly and becomes continuous with the cavity
of the mesenteron, and it became evident that the elongated blastopore
gives rise anteriorly to the neurenteric canal and posteriorly to the
permanent anus, while it closes in the middle part. Such a condition
is very transitory. In Rana halecina the blastopore closes and a new
anus is furmed by a downward extension of the mesenteron meeting the
epiblast, and an opening appearing at the point of fusion.

The hypothesis has already been advanced that the anus as formed
in frogs is an example of abbreviated development, and the author
believes that a study of Amblystoma clearly indicates along what road
such a process has gone. If, instead of the blastopore itself elongating
and remaining open, the cells of its posterior wall should extend back-
wards, and subsequently should separate to form a new opening, a
condition such as is found in the frog and toad would be reached, and
would be merely an abbreviation of what takes place in Amblystoma. A
study of this last-named form suggests that the neurenteric canal is that
portion of the primitive blastopore which has been closed in or caught
by the folding over of medullary folds. If this rising up of epiblast is
a secondary phenomenon or an abbreviation of an earlier condition, we
can see how by an elongation of the primitive blastopore its posterior
part escaped from being shut in, and remained as the anus of the adult.

Penetration of Spermatozoa into Ova of Frog.t—M. J. Massart
has shown that the spermatozoa of the frog are retained by the surfaces
with which they come into contact, and that they seek to increase their
surface of contact. Dewitz has observed somewhat analogous phenomena
in the spermatozoa of the cockroach. Massart is able, however, to

* Cire. John Hopkins Univ., viii. (1889) pp. 31-2.
+ Bull. Acad. R. Sci. Belg., xviii. (1889) pp. 215-20.

728 SUMMARY OF CURRENT RESEARCHES RELATING TO

propose a more thorough explanation of the entrance of the spermatozoon.
The jelly round the egg, swelling in contact with water, presents from
the surface inwards more and more dense strata. The spermatozoon,
once attracted to the ovum, tends to penetrate wholly in order to
experience the contact over its whole surface, and that as long as it meets
strata of increasing density. When the absorption of water by the jelly
is complete, the attraction which the strata of increasing density
exercised upon the spermatozoon ceases, and by this time a penetration
has probably occurred. M. Massart experimented with various gelatin-
ous substances, some of which worked as well as the jelly of the ova
themselves.

Spermatogenesis during Inanition.*—Dr. V. Grandis has experi-
mented with pigeons, and finds that a fast of a few days is sufficient to
alter the production of spermatozoa. When fasting it probably happens
that there is a cessation of the production of the elements which should
be converted into nematosperms, and that those only continue to grow
which have already begun to be developed. The new formation of cells
which is observed after the twelfth day of inanition is not destined for
the production of new nematosperms. During inanition spermatozoa
die in the interior of the seminiferous canaliculi. The elements of which
the testicle is composed break up when the loss of weight undergone by
the fasting animal is more than 40 per cent.; it is probable that this
alteration is effected to maintain the animal alive with the products
which result from the reduction of the testicle. The constituent
elements of the spermatic canaliculi which resist the effects of fasting
are, in decreasing order, the spermatozoa, the elements of the central,
and the elements of the median layer. The cells which are preserved
longest have the character of those which line the walls of these
canaliculi ; this important fact shows that, although the testicle may be
reduced to a third of its primitive dimensions, the elements which are
capable of giving rise to all the others are the last to disappear.

B. Histology.-+

Phenomena of Indirect Nuclear Fission in Investing Epithelia.t{—
Dr. O. Barbacci finds that the phenomena of indirect nuclear fission
persist completely in all the investing epithelia of the guinea-pig,
rabbit, and dog. The intensity with which the regenerative processes
are effected varies with the different organs to which the epithelium
belongs, with different animals, and with different individuals. Of the
three animals examined, the guinea-pig exhibits the most active processes
of regeneration; the other two are much less, although about equally,
active. The intensity with which the karyokinetic processes are
developed in investing membranes exhibits a complete independence of
the morphological characters of the epithelia themselves. There does
not appear to be any constant relation between the activity with which
regeneration is accomplished and the degree or quality of the function.
Although it cannot be absolutely demonstrated, it is very probable that
the phenomenon of indirect nuclear division, in investing epithelia, is not
continuous but intermittent, and this less for reasons of space than for
those of time.

* Arch. Ital. Biol., xii. (1889) pp. 215-22.
+ This section is limited to papers relating to Cells and Fibres.
t Arch, Ital. Viol., xii. (1889) pp. 184-6.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 129

Division and Degeneration of Giant-cells of Medulla of Bone.*—
M. H. Demarbaix has investigated the history of myeloplaxes or giant-
cells of the medulla of bone. He finds that during life, and for a short
time after death, they consist of a vesicular nucleus, formed of a mem-
brane, achromatic filaments, chromatic bodies, and a fluid or enchylema.
Arnold’s nuclei rich in chromatin do not exist during life; they appear
a short time after death, and are the altered form of the nuclei seen
during life. The alteration commences with a swelling of the chromatic
bodies ; the colourable part soon forms, on the inner face of the nucleus,
a continuous layer, which thickens more and more, and ends by occupying
the whole cavity of the nucleus. This change is quite independent of
micro-organisms, and occurs some time before the similar alteration of
the small cells of the medulla. Degenerated nuclei offer the same kind
of resistance to decolorizing ayents as do nuclei in kinesis; this appears
to indicate that the chromatin has undergone a modification by which it
becomes analogous to, if not identical with, the chromatin of karyokinetic
figures. The phenomena which Arnold has described under the name of
indirect division in the lymphatic cells of the medulla, the spleen, and
the lymphatic ganglia, are also post-mortem changes.

Multiple kinetic division was normally observed in the myeloplaxes
of all the animals examined by the author, and must therefore be re-
garded as a physiological process; the statement of Cornil that there is
no binary division in the giant-cells is incorrect. Multiple kinetic
division is the only well-established mode of division, and the proofs of
direct division are capable of other interpretations, among which the
hypothesis of phagocytosis must be taken into consideration.

In the normal state a certain number of cells present phenomena of
retrograde development; these are of two kinds ; in the first the nucleus
is converted into a drop of homogeneous semi-liquid substance, which
may further divide into a number of smaller drops, and these are some-
times expelled from the protoplasm; in the second method the proto-
plasm disappears rapidly ; the colourable part of the nucleus forms on
its inner surface a refractive, continuous, and homogeneous layer.

Comparative Study of Striated Muscle.,—Mr. W. A. Haswell comes
to the conclusion that there are two principal types of striated muscle
in the Animal Kingdom—the simple and the compound—whieh are not
in any way genetically related to one another. Compound striated
muscular fibres are found in their most primitive, as well as in a more
highly developed, form in certain Polycheta, where they occur as the
equivalents of bundles of simple non-striated fibres found in a cor-
responding situation in related forms. Each compound striated fibre is
derived from a bundle of simple non-striated fibres. In its simplest
form (in the pharynx of a species of Syllis) the compound striated fibre
has only a single transverse network running through a zone of singly
refracting substance situated at about the middle of the fibre, with two
doubly refracting zones, one on either side of it. Ina slightly higher
stage two other transverse networks are added, one on either side of the
middle one; in other species of Syllis the fibres present from half-a-
dozen to twenty transverse networks. In Syllis coruscans, the species
in which the fibres are most highly developed, they have all the essential

* La Cellule, v. (1889) pp. 27-57 (2 pls.).
t+ Quart. Journ. Micr. Sci., xxx. (1889) pp. 31-50 (2 pls.).

730 SUMMARY OF CURRENT RESEARCHES RELATING TO

characteristics of the striated fibres of the Arthropoda, differing only in
the greater coarseness of the fibrils and of the networks. The develop-
ment of the primitively simple transverse network from intranuclear
filaments of adjacent intrinsic nuclei of the non-striated fibres is ren-
dered probable by the correspondence of the transverse band of nuclei
with the transverse network, and the replacement of the former by the
latter. The author proposes to deal with the simple type of striated
muscular fibre in another memoir.

Growth of Transversely Striated Muscle.*—Dr. W. Felix has made
some observations on the growth of transversely striated muscle, chiefly
based on the study of human embryos.

He finds that the young muscular fibre is hollow, and that the time
when it becomes solid is different for the same muscles in embryos of the
same age and for different muscles in one and the same embryo. The
nuclei lie in the central cavity (axial nuclei), in the transversely
striated mantle-layer (mantle nuclei) and in the periphery of the fibre
(contour nuclei). The transversely striated mantle of young muscular
fibres is not complete, but often exhibits clefts of various leneths. The
diameter of the several fibres of one muscle often varies considerably ;
it increases a great deal till the third month, between the third and
fourth month there is a considerable fall, and then again a regular
increase. From the middle of the third month till the end of feetal life
we find in each muscle fibres with multiplying nuclei arranged in series.
These fibres fall into two groups. In the first the fibre possesses several
rows of nuclei in its mantle layer, and the brightly coloured nuclei of
the rows differ in form, size, and distance from one another. In the
median part of the row they are closely packed and pressed into all
possible forms ; this is the site of the greatest growth-energy (and in all
probability corresponds to the nerve-ending) ; away from this they are
round, and then elongated. The fibres break up into daughter-fibres,
each of which contains a row of nuclei. Around the fibre there is
formed a sheath rich in nuclei and vessels; this appears before the
formation of the rows, increases gradually in thickness, and becomes
concentrically striated. With increasing growth the sheath disappears.
Longitudinal division of fibres occurs not only in lately born infants,
but also in later years of life.

The muscular fibres of the second group contain only one row of
nuclei in the central cavity. The dark-coloured nuclei are arranged
transversely, and differ little in size, form, or distance from one another.
There is no spot of greatest growth-energy, and there are no relations
to the nerves. Longitudinal division of the fibres has not been observed.
These fibres are found in the muscles of embryos two or three months
old. The rows of nuclei are found almost regularly at the ends of the
fibres, and are the expression of an active increase in length. Parts of
the fibres of the second group break up, and their products resemble the
sarcoplasts of Margo and Paneth.

While the muscular system is being laid down new fibres of the
embryonic type are constantly being formed. As soon as all the fibres
are developed there is a pause in the increase of tlhe number of fibres;
this occurs in the third month. When increase begins again it is only

* Zeitschr. f. Wiss. Zool., xlviii. (1889) pp. 224-59 (2 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. Tal

effected by lonzitudinal division of the fibres already present, and that
appears to be henceforward the only method.

Fundamental Structure of Osseous Tissue.*—-M. O. Van der Stricht
has examined the fundamental structure of osseous tissue. He finds
that it presents great analogies to hyaline cartilage so far as its texture
and the arrangement of its histological elements are concerned. In
cartilage the fibrils have a tendency to form plexuses, and this tendency
is seen in the typical adult osseous tissue of long bones, at least in the
peripheral and complemental lamelle; it is less pronounced in the
circummedullary lamelle and in the Haversian systems; the tendency
exists, in a pronounced form, in the tissue of the foetal perichondrial bone
and in that which enters into the composition of the cochlea,

Tn this last the fibrils and bundles of fibrils are grouped in such a
way as to form a very finely fibrillated osseous substance surrounding
the Haversian canals, while others form an alveolar system which is
continuous across a wide extent of bone. The fibres and bundles of
fibrils are very closely connected with the bone-cells, and are, so far,
comparable to the intercapsular bundles of hyaline cartilage. These
close relations are to be explained by the mode of origin of the osseous
tissue ; in its formation two kinds of cells probably take part; “ fibrillo-
genous” connective cells giving rise to the fibrils, and osteoblasts to the
calcareous deposits.

Structure of Protoplasm.}—Prof. O. Biitschli sums up his conclusions
as to the vacuolar constitution of protoplasm which ke has repeated‘y
emphasized in regard to Amecebz, Noctiluca, marine Rhizopods, and
Ciliata. He has mimicked this structure by a fine emulsion of soap
with benzin and xylol. The vacuolar foam which results is very stable,
remaining in one case unaltered for two months. Again, acting cna
suggestion due to Quincke, he sought for fine foam which would remain
persistent in water or aqueous solutions. He reduced sugar or salt to
the finest powder, mixed it with some drops of old olive oil, and watched
under a Microscope the behaviour of drops of the mixture when immersed
in water. The water diffused into the oil, attracted by the crystal
particles, and changed these into minute vacuoles of salt or sugar
solution. In twenty-four hours the drops became milky white, and a
fine vacuolar structure resulted ; they were cleired with glycerin and
studied. The optical appearance of a network, of knots, of granulations,
of microsomata indeed was clearly exhibited. Moreover a fine limiting
membrane, like that of many cells, was formed. Still better results were
obtained by using finely pulverized potassium carbonate mixed with oil.
The slight evolution of carbonic acid gas from the free fat acid aided in
the process, and the mimic cells when slightly pressed showed streaming
movements like those of Ameba limax or Pelomyxa; in one case the
streaming lasted twenty-four hours, and after forty-eight hours was
restored by increased temperature. Biitschli explains the physics of
this interesting phenomenon, and emphasizes his conviction that such
artificial cells really shed much light alike on the structure and behaviour
of real organisms.

* Arch. de Biol., ix. (1889) pp. 27-53 (2 pls.).
+ Verh. Nat.-Med. Ver. Heidelberg, iv. (1889) pp. 12.

Ay SUMMARY OF CURRENT RESEARCHES RELATING TO

y. General.

Protoplasmic Movements and their Relation to Oxygen Pressure.*
—Mr. J. Clarke has made a long series of experiments in order to
ascertain the minimum pressure of oxygen necessary to restore the
streaming, ameeboid, and ciliary movements of protoplasm after they
have come to rest in the absence of that gas. The minimum for the
streaming movement in the plasmodia of Myxomycetes, and in the cells of
hairs and other tissues was found to vary from 1 mm. to over 3 mm.
With the vegetable cells the variation was much more extensive. The
age of the cell, and the conditions under which it has been developed,
influence to some extent the minimum oxygen pressure necessary to
restore movement. The time taken by the protoplasm to recover its
streaming movement is too short to be measured in cases where the
conditions are favourable, but increases as the cell-wall thickens, or the
cell ages, or as the length of time between the cessation of movement
and the introduction of the necessary oxygen supply. After ciliary
movement is arrested in any healthy infusorian by the absence of oxygen
the organism soon begins to disintegrate. The introduction of an
oxygen supply of about 1 mm. is sufficient to arrest disintegration and
restore ciliary movement, provided the breaking-up has not proceeded
too far. The growth of the plant, and the streaming of protoplasm in
the active cells thereof appear to be parallel phenomena; streaming, or at
least the power of very rapidly assuming the streaming movements,
is possessed by the parenchyma and, probably, the phloem of plants
so long as they continue to grow in an atmosphere of hydrogen.
Inability on the part of the protoplasm to continue these movements,
seems to be always associated with total cessation of growth.

Orientation of Animals towards Light.;—Herr J. Loeb has made
some observations on “animal heliotropism,” from which he concludes
that the same luminous stimuli as we consider to produce sensations in
ourselves affect all, and even the lowest eyeless animals, and this not-
withstanding the great differences in the development of specific helio-
tropic organs. The differentiation of these organs has, therefore, been
due to the fact that the laws of luminous stimulation remain unaltered.
Their influence must be due to a fundamental peculiarity of living
matter.

Orientation of Animals towards Gravity.{[—The same author dis-
cusses also the phenomena of “animal geotropism” ; he thinks it highly
probable that the muscular vibrations are of importance for orientation
in space, but he proposes to extend his inquiries.

B. INVERTEBRATA.

Zoology of Victoria.S—The eighteenth decade of this work edited
by Prof. M‘Coy contains figures and descriptions of a number of Polyzoa,
and of the Great Red King-Crab (Pseudocarcinus gigas). The male of
this crab is much larger than the female, having a carapace nearly a
foot in width, and is provided with immense powerful pincers. The
descriptions of the Polyzoa are, as before, drawn up by Mr. M‘Gillivray,

* Proc. Roy. Soc., xlvi. (1889) pp. 370-1.
+ SB. Physik. Med. Gesell. Wiirzburg, 1888, pp. 1-5. $ T.c., pp. 5-10.
§ ‘Prodromus of the Zoology of Victoria,’ xviii. (1889) pp. 171-80.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 133

and refer to, inter alia, Tesseradoma magnirostris, the zoarium of which is
covered by a thick epitheca, on which the only mark seen is the tubular
opening of the zocecial pore; when the epitheca is removed, the surface
is seen to be covered by large perforations, which, in old specimens, may
be filled in, or even become tubercular from the heaping up of calcareous
matter. Flosculipora pygmza forms tufts about 1/12 in. high, and
resembles a micrescopic bouquet of flowers; it is attached to the
zocecia of Catenicella. Three species of a well-marked group, for which
the name of Craspedozoum is proposed, are described ; the genus is allied
to Flustra and Psiflustra. Rhabdozowm Wilsoni forms small phytoid,
branching tufts an inch or more in height. In addition to the radical
fibres, there are a few hollow chitinous rods which arise from the sides of
the shoots, are beautifully transparent, glassy, and strongly convoluted
towards the summit.

Fresh-water Fauna of East Africa.*—Dr. A. F. Stuhlmann con-
tinues his account of the fresh-water fauna of East Africa.t He was much
interested by a species of Dero which he found in the sexual stage, when
the gills presented a different form to those of a-sexual individuals, A
new species of Aeolosoma with red oil-drops was observed. Two new
forms of leeches were seen, one of which was almost always ectoparasitic
on Ampullaria. Females of a species of Rhabditis were very common.
The fresh-water fauna of Quilimane does not differ essentially from that
of Zanzibar ; here again the greatest wealth of individuals was presented
by the Cypridz ; Copepods were rare, but a new species of Moina suddenly
appeared in enormous numbers in a Protopterus tank; males did not
appear for ten days. Very large Ampullarias (Lanistes) were present
everywhere ; the tip of their shell is nearly always eaten off and covered
by a thick network of Algz, mud, and débris. Various species of
Leeches were observed; of the Oligocheta Dero was very common ;
Eudrilus, Digaster, allies of Titanus, and Acanthodrilus were also seen.
In one case Conochilus volvox appeared in enormous quantities. ‘The
author is certainly making many very interesting discoveries.

Mollusca.

French Malacology.{—M. A. Locard has three contributions to our
knowledge of the Mollusca of France; the first consists of a series of
scattered notices on various marine species; the second is a monograph
of the species of the family Buccinide ; about fifty species are recognized
as living on the French coasts, a few of which are new. In the third
memoir the species of the genus Pecten are described ; of these there
are about thirty-five known forms. The author discusses the characters
which seem to be of specific value. The relative position of the auricles,
and the presence or absence of the byssal sinus are good characters for
forming groups, but lose their importance when species are being dis-
criminated.

Innervation of Osphradium of Mollusca.s—M. P. Pelseneer points
out that the osphradium appears to differ from other sensory organs in
not being innervated by the central ganglia ; it is further removed from
these than is the otocyst, and always seems to have relations with one

* SB. K. Preuss. Akad. Wiss., 1889, pp. 645-60. +t Ante, p. 494.
¢ Ann. Soe. Linn. de Lyon, xxxii. (1886) pp. 191-263; xxxiii. (1887) pp. 17-127
C1 pl.); xxxiv. (1888) pp. 133-287. § Comptes Rendus, cix. (1889) pp. 533-4,

734 SUMMARY OF CURRENT RESEARCHES RELATING TO

of the visceral ganglia. The osphradium may be more or less widely
separated from the visceral ganglion with which it is connected, as in
the Gastropoda, or quite close to it as in the Lamellibranchiata.
The second arrangement is the better for testing whether the nerve-
fibres which end in the osphradium arise from the visceral ganglion
itseif or from the cerebral ganglion. Transverse sections through the
cephalic extremity of the visceral ganglion of Mactra show that some of
the fibres of the cerebro-visceral connective do not penetrate into the
visceral ganglion, but go outside it and directly to the osphradium,
into which no nerve coming from the visceral ganglion passes. The
osphradium, therefore, does not differ from the other sensory organs of
the Mollusca in the origin of its nerve-supply.

a. Cephalopoda.

New Phenomenon of Cleavage in Ovum of Cephalopods.*—Mr. S.
Watase has a preliminary communication on a curious phenomenon in
the cleavage of the blastoderm of Loligo pealii. The ovum exhibits
distinct bilateral symmetry. In some preparations the nuclei in the left
half were found to be dividing, while those on the right side were at
rest, and in others the phases of activity were reversed. The author has
followed up the alternating phases of activity and rest in the two halves
of the bilateral blastoderm, until 116 segments were formed. The
phenomenon, whether pathological or normal, probably has some im-
portant bearing upon the problem of bilateral symmetry, and may .
possibly throw light on the bilateral symmetry of form and function in
all its degrees of evolution.

B. Pteropoda.

Anatomy and Histology of Cymbuliopsis calceola.j—Mr. J. I.
Peck has had the opportunity of making serial sections of this Pteropod.
The muscular system is almost entirely limited to the regularly inter-
crossing separate bands that furnish the fin; the outer layers of these
lie diagonally at the sides. Just within them there is a layer, the fibres
of which pass from cue edge of the fin across to the other in arcs of
concentric circles. Still more deeply there is a layer of muscle-bands
that radiate from the proboscis to the margin. Hach edge of the
proboscis is rolled outwards into two diverging folds that form a ciliated
groove leading to the large mouth. This is devoid of any remnant of
buccal armature or salivary glands; mucous secreting cells are abundant
in the cesophagus; the “liver” does not open into the stomach by any
proper duct, but by a single, wide, direct communication, The herma-
phrodite gland almost completely envelopes the visceral mass; the
accessory reproductive glands are large and much compressed into folds ;
the genital ducts are strongly pigmented and are ciliated throughout.

In addition to the parts of the nervous system already described for
Cymbulia there is an additional commissure connecting the large pedal
ganglia.

Systematic Position of Desmopterus papilio.j—Prof. P. Pelseneer
discusses the characters of this Pteropod lately described by Chun, and
placed by him in a new family of the Gymnosomata. It appears that it

* Circ. John Hopkins Uniy., viii. (1889) pp. 33-4. +t T.c¢., pp. 32-3.
{ Zool. Anzeig., xii, (1889) pp. 526-6.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. Too

is a well-marked Cymbulid which has lost its pseudoconch, and it differs
from a Gymnosomatous Pteropod in the following characters :—It has a
single pair of tentacles; the cerebral ganglia are on the sides of the
cesophagus, and not dorsal or applied one to the other; the foot has not
the characteristic horse-shoe shape, and there is a single hepatic duct.
It belongs to the family of the Cymbuliide, because it has no shell and
a deciduous pseudoconch ; the head exhibits a ventral flexure, and the
tentacles are symmetrical.

y. Gastropoda.

Gastropoda and Scaphopoda of the West Indian Seas.*—Mr. W.
H. Dall has issued the second part of his report on the Mollusea collected
in the Gulf of Mexico. A large number of new species are described,
and it is found that three families, the Pleurutomide, Ledide, and
Dentaliide, furnish nearly 28 per cent. of the species of the abyssal
fauna collected by the ‘Blake.’ Mr. Dall points out that the most
important characteristic of abyssal life is that it, and it alone, exhibits a
fauna in which the reciprocal struggle is nearly eliminated from the
factors inducing variation and modification. There is no mimicry or
sexual selection where all is dark. In the struggle for life of the
abyssal animal he is pitted against the physical character of his environ-
ment, and not against his neighbour or the rest of the fauna. Hence
we should have, and really do have, the process of evolution less obscured
by complications in the abyssal fauna than is possible elsewhere. From
a study of these animals in the light of their environment much may be
hoped towards the elucidation of great questions in biology, and
naturalists should strive to promote deep-sea dredging as essential to
the progress uf science. The rain of food from the sinking of weak or
dead surface forms is unquestionable, and the supply must, in the nature
of things as we know them, far exceed the demand. This is illustrated
by the absence or disappearance of protective devices in deep-sea species.
The genus most abundantly represented of all is Mangilia, which is
devoid of an operculum, and the diminution in size and solidity of these
protective appliances is marked in all the deep-sea Gastropods. Nearly
all the species are carnivorous by hereditary tendency. Those which
are not become so by necessity. The ornamentation of the shell in
deep-sea Gastropods may be explained in some cases as providing
buttresses for the strengthening of the fragile and delicate structures
that bear them. Their strength has to be sought for in corrugations of
their shell envelope. In the depths where every portion of the shell
must be permeated by the surrounding element to equalize the external
pressure, and where carbonic acid exerts its usual malign influence on
the limy parts of all organisms, we find a protective epidermis developed
in most unexpected places. ‘his is the explanation of the fact that in
characteristic abyssal animals we find those puzzling and remarkable
counterparts of land and fresh-water species of totally diverse groups,
which have astonished every student of the Mollusca who has seen
them.

Variations of Cardium edule.j—Mr. W. Bateson has investigated
in the Aral Sea and in Egyptian lagoons the variations of Cardium

* Bull. Mus. Comp. Zool. Camb., xviii. (1889) pp. 1-492 (21 pls.).
t+ Proc. Roy. Soc. Lond., xlvi. (1889) pp. 204-11.

736 SUMMARY OF CURRENT RESEARCHES RELATING TO

edule which appear to be correlated with the conditions of life. He
regards as the most important result the fact that the shells of each
sample, whether it be from a separate lake or only from a particular
level, have special characters, and are more like to each other than to
the shells of one of the other lakes or of another level. Again, the
shells which have lived under similar conditions, i.e. in very salt water,
resemble each other, having the characters of thinness, light colours,
small beaks, ribbing on the inside of the shell, and great relative length.
Similarly, the shells from the two isolated and independent fresh-water
lakes at Ramleh also present similar characters, viz. thickness, similar
texture, and shape. It is to be noted that the resemblance between the
cockle-shells from an Asiatic lagoon and those from Abu Kir becomes
still more striking when it is remembered that their immediate ancestry
is very different; the Asiatic shells had been living for many generations
in the brackish water of the Aral Sea, and had already become a well-
marked variety before being subjected to the new conditions, while those
which are found in Abu Kir must clearly be the immediate descendants
of animals of the type found in the Mediterranean. The author suggests
that in so far as any variation (as, for example, that of texture) occurs
universally among the shells of a given sample, it may be legitimately
supposed that they are correlated to the conditions under which they
lived. The terraces of Shumish Kul give an opportunity for the com-
parison of several distinct stages in the origin of a natural variation,
which appears to be almost unique.

Luminous Phenomena in Pholas dactylus.*—M. R. Dubois. has
been much struck with the sensitiveness to light exhibited by the eyeless
Pholas dactylus. The contractile warning apparatus is made up of
muscular segments which are merely the continuation of the pigmented
epithelial elements which form a continuous layer on the siphon, beneath
the cuticle. The pigmented segment and the muscular segment together
form the photomuscular element. This warning apparatus is in more
or less direct relation to the sensory elements of the periphery. When
a ray of light falls on the surface of the siphon (“photodermatic
retina”), it traverses the cuticle and exercises its action on the proto-
plasm of the pigmented segments. The modifications caused by this
luminous radiation also determine a contraction of the muscular segment.
This contraction disturbs the peripheral nervous elements just as if the
siphon had been excited mechanically by touching its surface, and pro-
vokes a reflex contraction analogous to that of the iris when a ray of
light strikes the retina. The mechanism of vision is, therefore, reduced
to a true tactile phenomenon.

The constituent elements of the organs of Panceri, in place of being
covered by a refractive cuticle, carry vibratile cilia. They are formed
of a calyciform epithelial segment which is directly continuous with a
muscular segment, and make up the myophotogenic segment. In the
fresh state the calyciform epithelial elements are filled with a substance
which they extrude when excited; in the midst of these, in the mucus
which has become phosphorescent, there are numerous migratory blood-
cells and the Bacterium pholas which the author has already described.

The most striking point is the great resemblance in structure and
function between the parts which perform the photodermatic function

* Comptes Rendus, cix. (1889) pp. 233-5.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. tat

and those for the photogenic function. The former, however, is provoked
by luminous vibrations from without, while the latter has, as its final
result, the emission of luminous radiations into the surrounding medium.

Nudibranchiate Mollusca of Plymouth Sound.*—Mr. W. Garstang
enumerates twenty-four genera and thirty-six species of nudibranchiate
Mollusca from Plymouth Sound. Among the valuable captures are two
examples of Idalia aspersa and three of Lomanotus. The author has
endeavoured to furnish facts regarding the life-conditions of this group.
Evidence is rapidly accumulating to prove that, in it, colour, whether
conspicuous or dull, has a very important value for the individual and
the species. Some cases of what appear to be mimicry are reported.
With regard to the bright colours of the papille of Aeolids the author
suggests that, in addition to their main purpose of warning enemies of
the presence of disagreeable qualities (e. g. nematocysts), there is another.
The bright colours are confined to the pspille which can be detached
from the body with the greatest ease and are reformed to their full size
in two or three days; this arrangement must be serviceable in directing
the experimental attacks of young and inexperienced enemies to the non-
vital papille, and away from the vital, inconspicuously coloured parts of
the body.

Microscopic Anatomy of Dentalium.t—Prof. H. Fol considers that a
genus which represents by itself a class of the Animal Kingdom always
deserves close study, but we cannot, we fear, give him all the space
which his detailed monograph demands.

The ectoderm forms a simple epithelium over all the free surface of
Dentalium, but the thickness of the layer varies in different regions and
with the condition of retraction or extension in which the parts are
found ; the cells are in some parts flattened, and in others cylindricai.
As in Lamellibranchs, there are a number of cutaneous glands, all of
which are unicellular, and of which there are two types, which are
respectively distinguished as the hyaline and the granular glands.

It is probable that the glandular tissue plays a part in the formation
of the shell, but this may not be its only function. All the ectoderm
except that covered by the shell is ciliated. The epithelium of the
digestive tract forms a single layer which is comparatively deep, for the
cells are elongated in the perpendicular direction ; some of the cells are
ciliated and some glandu'ar, but it is probable that all are ciliated when
young. The ciliated cells present an interesting peculiarity which the
author believes to be very common in the Animal Kingdom, though not so
well marked as in Dentalium. The cilia are implanted in a layer which
is more transparent than the subjacent part of the cell; when this trans-
parent layer is closely examined, it is seen to be crossed by pale lines
which appear to correspond exactly to the cilia. In the middle of each
of these strie there is to be seen, in preparations which have been
treated with carmine after Grenacher’s method, a small corpuscle
coloured a deep red like the nucleus. Finally, the part of the cell which
is situated between the nucleus and the transparent layer is traversed by
strize almost perpendicular to the surface, which seem to have a relation
to the cilia. The author gives some details as to the structure of the
radula and the parts connected with it. The liver is a collection of czeca

* Journ. Marine Biol. Assoc., i. (1889) pp. 173-98.
¢ Arch. Zcol. Expér. et Gén., vii. (1889) pp. 91-148 (4 pls.).

1889, 3 °F

738 SUMMARY OF CURRENT RESEARCHES RELATING TO

which open into the stomach, and though the mucous membrane of these
two organs sirikingly differs, there is a gradual transition which makes
it difficult to mark the boundary between them. The protoplasm of the
hepatic cells has a spongy texture; in section there is revealed a system
of large spaces, the trabecule of which are irregular in appearance.

No one has yet described the histology of the nerve-ganglia, the
general arrangement of which has been so well explained by Lacaze-
Duthiers. They are composed of large ganglionic cells, small ganglionic
cells, and fibrillar tissue, all of which are regularly arranged. The two
cerebral ganglia are really one ganglion subdivided by a constriction
in the sagittal plane; the substance, which consists of large and small
ganglionic cells, extends uninterruptedly from one ganglion to the other ;
the tissue with large ganglionic cells forms the cortical layer below and
at the sides; that with small cells is found on the dorsal surface. The
fibrillar substance, which corresponds to the white substance in the
brain of Vertebrates, occupies the whole of the interior of the ganglia.
In the pedal ganglia there is not the same distinction between the two
kinds of ganglionic tissue; the whole of the cortical layer, except at
the points of origin of the nerves, is formed by cells of medium size, and
the whole of the interior is occupied by the fibrillar substance; the
latter alone extends uninterruptedly from one ganglion to the other, and
so we have really a pair of ganglia. The other ganglia do not, from the
histological point of view, deserve their name; ganglionic cells are only
scattered on their surface, and there is no continuous layer. The author
enters into a good deal of detail in this portion of his memoir.

Histologically, all the muscular fibres of Dentalium, to whatever
organ they belong, are of the same structure ; they are very long fibres,
oval or circular in section, and rendered more or less polyhedral by
mutual pressure. They only vary in length; the very long fibres are
found in the locomotor organs, and the shortest in the region of the
intestine. The nucleus of the fibre is always excentric in position; the
amount of granular sarcode which surrounds the nucleus, especially at
its extremities, is reduced in the fibres of the adult to a scarcely per-
ceptible minimum. The several muscular organs are fully described.

The blood of Dentalium is colourless, and contains nucleated cells
which recall the white blood-corpuscles of Vertebrates. The state-
ment of Lacaze-Duthiers that there is no heart is too absolute. Physio-
logically, it is true that Dentalium has no heart comparable to that which
propels the blood in higher Molluscs, but, on the other hand, M. Fol
shows that the “perianal sinus” is provided with muscles, which, from
the morphological point of view, he cannot imagine any one refusing to
regard as the homologue of the heart of other Molluscs. ‘This circum-
anal sinus (as it had better be called) has a delicate wall formed by an
epithelium with flattened and spread-out cells ; externally to this there
are ribbon-like muscular fibres which are generally arranged parallel to
one another, and leave between them free spaces which are about four
times as wide as a fibre. Most of the fibres are set longitudinally, but
a few run across and make angles with the rest. The other sinuses do
not seem to possess either muscles or a true endothelial layer, and such
are true sinuses. In a transparent Dentalium the author has seen, under
the Microscope, the contractions of the circumanal vessel, The question
as to whether the simplicity of the cardiac arrangements of Dentalium is
acquired (or degenerated) or primitive must as yet remain open.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 739

The glandular epithelium of the kidney is distinguished, at first
sight, from that of the liver by the wider and less elongated form of the
cells which compose it; as in all the glands, these cells are arranged in
a single layer; the texture of the protoplasm is reticulated or spongy in
the region of the nucleus, while the apical part has a more complex and
very variable structure. In each cell one sees one to three balls of a
very granular substance, distinctly yellowish in colour; there may also
be, though they are rarer, colourless bodies. The apical part of the
cell is very fragile, and it is almost impossible to get really satisfactory
sections ; there do not appear to be cilia in the renal celis, for Lacaze-
Duthiers, Plate, and the author have all failed to find them.

The gonads are exceedingly simple, being in the form of a longi-
tudinal fascicle, which has on its lateral edges a number of dilatations ;
the sac has a delicate wall, and is, primarily, closed. There are no
traces at all of hermaphroditism. The gonad of the adult contains cells
in all stages of differentiation, but the transition is always made in the
most simple and natural manner, “sans aucune de ces complications
romanesques qu'il est de mode de trouver et de rendre incompréhensibles
a V’aide d'une nomenclature qui varie 4 la fantaisie de chaque auteur.”
With regard to the vexed question of the presence of an efferent duct to
the gonads, the author says that there is no doubt as to the existence of
the excretory canal which Lacaze-Duthiers described as extending along
the whole length of the gonad, but it is not a canal from the histological
point of view ; it is merely an excavation of the axial part of the gonad
and its lobes, hollowed out in the genital products and quite devoid of
any epithelial or cuticular membrane. The canal may be followed in a
series of sections, but it can only be seen when the sexual products are
on the point of maturity.

The author concludes with an account of the tentaculiform filaments,
but does not find himself able to speak definitely of their morphology ;
he endorses, therefore, Lacaze-Duthiers’ condemnation of the group-
name, Cirribranchiata, which has been proposed for Dentalium, and
states that he is in complete accord with that naturalist as to the
systematic position of the genus.

6. Lamellibranchiata.

Movements of Bivalve Mollusca.*—Mr. D. M:Alpine communicates
some observations on the movements of the entire detached animal, and
of detached ciliated parts of bivalve molluscs, viz. gills, mantle-lobes,
labial palps, and foot; these studies were made on Mytilus edulis. He
finds that the entire animal, when removed from the shell, moves, the
movements being rotatory, and at an average of fifteen minutes per round ;
the power of movement was retained for twenty-one hours in one case
and fifty and a half in another. Detached mantle-lobes, gills, labial
palps, and foot, either entire or in parts, also move. These the author
describes in some detail. The movements are not entirely due to the
action of cilia, for muscular contraction plays a most important réle in
altering the shape and dimensions of the part, and in giving it outlines
which enable it to get rid of obstacles or to make a more judicious use
of its motive power. The ciliary and other activity of all these parts is
stimulated by direct mechanical irritation. It appears that there is just

* Proc, R. Soe, Edinb., xv. (1887-8) pp. 173-204.
Si ke

740 SUMMARY OF CURRENT RESEARCHES RELATING TO

as much reason to recognize volition in the detached parts as in the
ciliated Infusoria, from the fact that the direction of the moving pieces
of the gill is so frequently changed as they pass from point to point on
a moistened plate. In the common sea-mussel there is a latent power of
independent movement in the entire animal, as well as in the detached
parts, which has hitherto escaped notice.

Abranchiate Lamellibranchiata.*—Mr. W. H. Dall calls attention
to his work on Cuspidaria and allied forms, which was ignored, he thinks,
by M. P. Pelseneer.t| Of this M. Pelseneer { offers an explanation, and
proceeds to discuss some other points raised by Mr. Dall. The latter
had doubted whether the Belgian naturalist had really seen examples of
Lyonsiella Sars and Silenia Smith, to which the answer is that the ex-
amples of Lyonsiella were named by Mr. Sars, and those of Silenia were
the types. There cannot be, as Dall supposes, any progressive develop-
ment of the gill from Cuspidaria to Lyonsiella, but the contrary, for the
gill is a more archaic organ than the muscular septum. The septa of
the Septibranchiata are not, as Dall says, delicate membranes, but thick
muscular septa, and the spaces seen are not artifacts, but, as the plates
in the ‘ Challenger’ Report show, constant and symmetrical holes, with
definite lips.

Molluscoida.
a, Tunicata.

Origin of Test-cells of Ascidians.s—Mr. T. H. Morgan has a pre-
liminary notice of his investigations on this disputed question. Obser-
vations were very satisfactorily made on Cynthia partita. Ova and
follicular cells, in their earliest condition, appear as nuclei in the
flattened epithelial membrane which forms the wall of the oviduct. One
of the nuclei enlarges, protoplasm is formed around it, and it becomes
an ovum, around which some of the other nuclei arrange themselves. At
the same time the surrounding nuclei collect protoplasm about them-
selves, and this spreads over the ovum; in the layer thus formed the
follicular nuclei le as in a syncytium. These follicular nuclei increase
in number by division, and the peripheral zone of protoplasm widens;
at certain places this zone next projects slightly into the yolk, and at
the same time the follicular nuclei migrate into the projections. These
plugs of protoplasm, with the contained nuclei, become gradually con-
stricted off from the follicular zone and form the test-cells just within
the follicle. The ovum, test-cells, and follicular cells are all homologous.

In Clavellina the young follicular nuclei remain on the outside of the
protoplasmic zone; later, some of the nuclei niigrate into the zone and
the follicular membrane is formed in the centre of this protoplasmic
ring; it encircles the‘egg, and test-cells become separated from follicle-
cells.

B. Bryozoa.

Anatomy of Phoronis australis. ||—Dr. W. B. Benham has had an
opportunity of studying the anatomy of this comparatively large species
of Phoronis. The mouth is a wide, though compressed, funnel-shaped
opening, the corners of which are continued as grooves between the

* Bull. Soc. Zool. France, xiii. (1888) pp. 207-9.

+ This Journal, 1888, p. 564. { Buil. Soc. Zool, France, xiv. (1889) pp. 111-3.
§ Cire. John Hopkins Uniy., viii. (1889) p. 63.

|| Quart. Journ. Mier. Sei., xxx. (1889) pp. 125-58 (4 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. TAL

tentacles. The lophophore varies in shape in different species, and the
tentacles vary in length. Hach tentacle has an epidermis consisting
of a single row of cells over the greater part of the surface, but on
the inner surface it is two or three cells deep, and those of the
outer layer here carry long cilia. Within the epidermis is a ring of
tissue which forms the skeleton ; this encloses a spacious cavity, which
is continuous below with the celom. A nerve passes up each tentacle
on its inner side. The tentacles are not united by a true membrane, as,
for instance, in Plumatella, but are merely connected together by the
trabeculz of basement-tissue.

The pit at the base of the inner series of tentacles does not seem, as
some authors have thought, to be sensory, but rather glandular. The
epistome has not the appearance figured by Allman, whose representa-
tion conveys quite a wrong idea. Its dorsal surface is covered by a
cubical epithelium, continuous with and similar to the surrounding
epidermis ; its oral surface agrees with the epithelium of the cesophagus,
and consists of very elongated, narrow, columnar cells carrying cilia.
At the base of these is seen nervous tissue.

The nervous system lies immediately below the epidermis; between
the basement tissue and the epidermis there is a narrow layer of granular
substance, which is not stained in borax-carmine; in this layer there are
a few rounded nuclei belonging to small nerve-cells, and numerous
delicate fibres crossing the granular substance from the overlying
epidermal cells. This is the nerve-band; it follows the lophophore,
passing all round the oral side of the animal, and curves round at the
sides of the nephridial ridges, following the spiral course of the lopho-
phore. From this band a nerve goes to each tentacle and nephridium.
There is no concentration to form a ganglion anywhere. After giving
some further details, the author describes the digestive system. The
ceelom is divided into two very unequal cavities by a septum, the histo-
logical structure of which is of some interest. It consists of a nearly
homogeneous dense matrix, sometimes fibrous, in which are imbedded
small spindle-shaped cells with rounded nuclei. Here and there are
larger and smaller spaces, lined by cells, which appear to place the
supraseptal in communication with the infraseptal cavity.

After some observations on the vascular system, nephridia, and
gonads, the author enumerates and defines the known species of Phoronis,
and then passes to consider the relations of the genus to other animals.
So far as the Brachiopoda are concerned, resemblances are certainly to
be seen in the arrangement of the tentacles and the division of the
ceelom into a visceral and a tentacular cavity, but detailed comparison
of adults, of larvae, of the modes of development, shows that there is no
close relation between Phoronis and the Brachiopods. At first sight
Phoronis has a great resemblance to the Polyzoa, but the differences in
structure are very considerable. Thus Phoronis has a closed vascular
system, and the Polyzoa have none; the Polyzoa have a suboesophageal
ganglion, while the nervous system of Phoronis is in an embryonic
condition. The gonads of Phoronis are unpaired, of the Polyzoa paired,
and the mode of origin of the mesoblast is very different in the two groups.
On the whole, this difficult form seems to stand nearest to the Sipunculids,
especially in the developmental history, where there are many, some
important, points of similarity. The arrangement of the alimentary canal
is the same in both, and it has the dorsal flexure found in the trochosphere.

742 SUMMARY OF CURRENT RESEARCHES RELATING TO

Arthropoda.
Origin of Malpighian Tubules in Arthropoda.*—Mr. F. H. Beddard

points out that in a species of Acanthodrilus minute cecal diverticula
arise at irregular intervals from the gut. They are at first tubular in
character, and are lined by an epithelium identical with that of the
intestine ; as they get further away from their point of opening into the
intestine they lose their tubular character and become continuous with
undoubted nephridial tubules, with a duct excavated in the substance of
their cells ; the tubules, which are at first intercellular, become afterwards
intracellular; they are absolutely indistinguishable from the nephridia,
and appear to join the general nephridial network of their segment.
These nephridial appendages are branched and anastomose with one
another, and they may certainly be compared to the anal nephridia of
the Gephyrea. It is only necessary to limit their number and arrange
them regularly to convert them into Malpighian tubules.

Eye of Decaped Crustaceans and Arachnids.j—Prof. J. Carriére
makes a critical review of recent observations by Reichenbach, Patten,
Kingsley, Bertkau, Mark, Parker, and Herrick, on the structure and
development of Arthropod eyes. He does not commit himself in the
meantime to definite conclusions, which he leads us, however, to expect
from a forthcoming work.

a. Insecta.

Function of Palps in Insects.t— Herr E. Wasmann cannot accept
the conclusion of Plateau that the palps are useless to gnawing insects
in the ingestion of food. The fact that the palps of such insects as
are fed hy others are reduced or completely aborted seems to show that
the palps must play an important part when food is independently
acquired. On this point the author enlarges with a good deal of detail.
We can only suppose what the function of the palps is; it is probable
that they seek for and test suitable food ; in forms such as Atemeles or
Lomechusa, which have a semiparasitic mode of life, the labial palps are
reduced, while the maxillary palps are long and well developed.

Some Coleoptera regularly use their maxillary palps as fingers by
means of which they push the morsel into the mouth, e. g. Hydrophilus
piceus ; this same species is unable to take in food when all its palps are
removed, while others, as Dytiscus marginalis, take food with less care.
If the antenne of D. marginalis are removed, that insect can find food by
means of its palps, but if they also are removed the creature will die of
hunger.

Double Plexus of Nervures in Insects’ Wings.§—Dr. H. A. Hagen
gives a photograph of a split wing of Aeschna heros. The wings of any
insect can be split before the membranes become closely connected ;
the period varies with the size of the object and the temperature on the
day of development, but is rarely more than twenty-four hours. The
necessary operation is very simple; the wing is cut off at its base and,
under water, is blown out by means of a small tube, and is then cut
along its hinder margin. It is spread out on paper or glass under water,
and is then carefully dried.

* Ann. and Mag. Nat. Hist., iv. (1889) pp. 290-2,
+ Biolog. Centralbl., ix. (1889) pp. 225-34.
¢ Biol. Centralbl., ix. (1889) pp. 303-8. § Zool. Anzeig., xii. (1889) pp. 377-8.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 743

Structure and Phylogenetic Significance of Embryonic Abdominal
Appendages in Insects.*—Prof. V. Graber remarks that there are two
facts which seem to show that the present meropodous Insects are derived
from forms that had appendages on all their trunk-segments. The
first of these is the presence of appendages on all the segments of the
lower apterous Insects, and the other is the presence of ventral abdomi-
nal appendages in the embryos of the most various kinds of Insects,
It is, however, to be noted that these embryonic appendages often
disappear before they have passed beyond an altogether indifferent stage,
and that, therefore, they tell us nothing as to the nature of the structures
which have disappeared; the appendages on the first segment lead us
to suppose that they are the remains of myriopodiform legs. The
ventral appendages in Stenobothrus have a large lumen, and the cells of
their outer wall are of enormous size; the coagulation found on making
sections seems to be partly, at least, secreted by cells of the ventral
saccules which are not limited by any chitinous membrane; or, in other
words, these appendages appear to be truly glandular. A number of the
statements and arguments used by Cholodkowsky in his recent memoir
are traversed.

Markings of Lepidoptera in the Genus Ornithoptera.t—Dr. C.
Fickert has investizated this subject with great minuteness, comparing
species with species, and variety with variety, in intricate details of
shades and dimensions. He believes that the varieties and species can
be arranged in a series so orderly, that the notion of fortuitous variation
is excluded, and that of progressive constitutional growth, as emphasized
by Eimer, confirmed. In Ornithoptera priamus, to which special atten-
tion is paid, the author finds a species in process of rapid phyletic
progiess. Some of its varieties—O. arruana, richmondia, priamus, and
lydius are now constant; others, e.g. O. pegasus, are still very unstable
in both sexes ; while in others, e.g. O. cresus, the males are constant,
but the females are unstable. Specific change is like varietal, the direc-
tions in both are few and definite, separation in space has been of much
importance, and the females conserve longest the original characteristics.
The interesting fact is pointed out that the caterpillar stage may some-
times in its markings advance beyond what is attained by the adult
butterfly, the progressive variability being in such cases apparently
predominant in one phase of life. The paper affords interesting corro-
boration of Eimer’s results.

Spermatogenesis in Lepidoptera.t—Herr G. Platner finds (1) that
the centrosoma of the spermatocyte forms the apical portion of the
spermatozoon, (2) that the rest of the head is formed solely from the
chromatin of the spermatide nucleus, and (3) that the accessory nuclear
body arising from the substance of the nuclear spindle (in the sperma-
tocyte) is modified as a sheath for the axial filament of the spermato-
zoon.

Following a now well-established terminology, Platner distinguishes
—(1) the last generation of cells as spermatides, (2) the penultimate as
spermatocytes of the second order, (8) the antepenultimate as sperma-
tocytes of the first order, and (4) previous generations of cells as

* Biol. Centralbl., ix. (1889) pp. 355-63.
+ Zool. Jahrb., iv. (1889) pp. 692-770 (8 pls.).
} Arch. Mikr. Anat., xxxiii. (1889) pp. 192-293 (1 pl.).

744 SUMMARY OF CURRENT RESEARCHES RELATING TO

spermatogonia. The spermatocytes correspond to ova; the two divi-
sions which they exhibit represent the extrusions of polar bodies. In
both cases there is a reduction of the chromatin to one-fourth of the
original quantity, and the second division follows on the heels of the
first without an intervening resting stage. The author works out in
detail the parallelism between ovum and spermatocyte, and points out
that Weismann’s distinction between the first and second polar body,
should logically hold true also for the products of spermatocyte division.
These, however, are all equal and similar. In regard to the formation
of polar bodies, Platner notes that the ovum at the time of extruding the
first polar body contains only the naked centrosoma without any trace
of archoplasma. The latter appears for the first time on the origin of
the polar radiations round each centrosoma, and its previous absence
may perhaps explain the inequality of the division in the formation of
the polar bodies. In addition to the above-mentioned parallelism
between ovum and spermatocyte, one of the most interesting facts con-
firmed by Platner’s research is the importance of the centrosoma as a
cell-centre.

Habits of certain Borneo Butterflies.*—Mr. 8. B. J. Skertchly
finds that in the forest depths butterflies are rare, most delighting either
in the sunshine, or flying where it is close at hand. It is not the case
that a number of butterflies are to be found high overhead on the forest-
tops; nowhere, even where trees were in flower, were butterflies seen in
numbe”, although other kinds of insects were not rare. The majority of
butterflies still fly near the ground, and possibly all did so originally.
In Borneo neither does heavy weather debar them, nor do flowering
creepers attract them to fly high; “this seems to point, as many facts
do, t» butterflies being still as much terrestrial as aerial creatures.”

In dealing with the habits of particular species, the author notes
that, in some cases, the females woo the males, and in some cases are
both wooerand chooser. As there seems to be so little relation between
the habits, beauty, and numbers of the sexes, and the sex of the wooer,
it is difficult to see why we should introduce the complex machinery of
sexual selection to perform what the ordinary laws of evolution seem
equally capable of carrying out. Leptocircus curius has the habit of
pushing its proboscis into wet sand, taking long steady drinks, and
pu nping the water out astern in rhythmic squirts.

Odoriferous Glands of Blaps mortisaga.|—Prof. G. Gilson has
examined the structure of the odoriferous glands of this Coleopteron,
and of some other species. In Blaps the odoriferous apparatus is very
well developed, and consists of cutaneous unicellular glands; these cells
are so arranged as to form lobes which resemble glandular tubes, from
which they essentially differ in that each cell has a special excretory tube.
In each cell four parts can be distinguished ; there isa radiated vesicle, a
central ampulla, a delicate excretory tube, and a tube-sheath. The
solid portions of these parts are intimately connected with the reticulum
of the cytoplasm. The internal rays of the vesicle, and of the sheath
are orderly, and strengthened by radial trabecule of the cytoplasm.
The membrane of the vesicle, and those of the sheath, tube, and ampulla,
are formations which are analogous to cellular and nucleated membranes,

* Ann. and Mag. Nat. Hist., iv. (1889) pp. 209-18.
+ La Cellule, vy. (1889) pp. 3-21 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 745

and are formed from the cytoplasm. The radiation of the reticulum has
not necessarily its centre in the nucleus of the cell; very different
cytoplasmic formations, such as the radiated vesicle, the sheath, and the
excretory tube, may afford insertion for the greater number of the radial
trabecule.

Glandular Structure on Abdomen of Embryos of Hemiptera.* —
Mr. W. M. Wheeler describes on the first abdominal segment of embryos
of Cicada septemdecim a pair of invaginate glandular structures
apparently homologous with similar, but evaginate appendages on other
insects. In relation to the latter, there has been much diversity of
opinion, but the author’s investizations on Blatta have convinced him
that they are neither sensory nor branchial organs, but glands. bo is it
with the invaginations seen on Cicada and Nepa. The function of the
apparently degenerate glands was probably odoriferous.

Life-history of Ghermes.t—Herr N. Cholodkovsky has continued
his observations on the life-history of Chermes. He finds that C. strobi
has no relation to C. coccineus, but to a new and undescribed “ species”
which he names provisionally C. sibiricus. C. coccineus is found to
wander from the pine to the white fir, and in the succeeding summer
returns to the pine, where it lays the eggs which give rise to the black
males and females. Another “species” which the author calls C.
lapponicus, wanders, in St. Petersburg, on to the larch, and, therefore, is
an ally of C. hamadryas. The author must be understood to use these
new species merely for the purpose of better discrimination. Further
details are promised.

Dr. L. Dreyfus} has a critical and destructive article on Prof.
Blochmann’s recent essay on the Cycle of Generations in Chermes abietis.
For the details of the dispute, reference must be made to the original.

Hypodermis of Periplaneta.s—Dr. P. Mingazzini investigated the
hypodermis of Periplaneta orientalis to see if Minchin was right in his
conclusion that the dorsal hypodermis of the abdominal segments con-
sisted of two strata of cells, the outer chitinogenous, and the lower
ganglionic. There are indeed large inferior cells, but these are not
nervous, but merely epithelial, derived from the outer layer, and greatly
increased in size. They are apparently specialized glandular cells of
the epidermis, branched in form, large in size, and segregated from the
chitinogenous layer. As to a special gland discovered by Minchin on
the dorsal intersegmental membrane of the sixth abdominal ring, its cells
are quite homologous with those of the general stratum under discussion.

Malpighian Tubules of Libellula depressa.||—Dr. A. B. Griffiths
adds the dragon-fly to the number of animals in which he has found uric
acid; it is to be found in the Malpighian tubes, in which no other
ingredient could be detected.

y. Prototracheata.

Brain of Peripatus.1.—M. G. Saint-Remy chiefly describes the
internal structure of the brain of Peripatus, as Balfour's account is very

* Zool. Anzeig., xii. (1889) pp. 500-4. t T. c., pp. 387-91.
t Biol. Centralbl., ix. (1889) pp. 363-76.

§ Atti R. Accad. Lincei (Rend.), v. (1889) pp. 573-8.

|| Proc. R. Soc, Edinb., xv. (1887-8) pp. 401-3.

—{ Comptes Rendus, cix. (1889) pp. 315-7.

746 SUMMARY OF CURRENT RESEARCHES RELATING TO

incomplete. The neurilemma is a very thick, hyaline membrane, which
almost always breaks away from sections, and so escaped the notice of
Balfour. The cerebral cortex is almost completely made up of small cells
which are very poor in protoplasm ; some, almost reduced to their nuclei,
form a considerable aggregation—the anterior ganglionic mass—in each
half of the brain. ‘he cephalic ganglion corresponds to the “ prote-
cerebrum” and “ deutocerebrum” of Insects, but forms a very homo-
geneous whole. The author gives the name of optic lobe to a ganglionic
region which, contrary to the description by Carriére of P. edwardsi,
exists behind the retina. There is no true optic nerve, but a short
pedicle of dotted substance traverses the cerebral cortex and passes at once
into the eye. The two symmetrical regions whence the optic pedicles arise
are connected by a commissure. The anterior medullary mass is large,
ovoid, and formed of dotted substance ; it sends forward into the anterior
ganglionic mass some large ramifications, which divide there and receive
the continuations of the small cells. 'The medullary mass appears to be
connected with its homologue of the opposite side by a small commis-
sural cord. ‘The whole system reminds the author of the pedunculated
body of Insects; there is a dorsal pad which resembles in its structure
the stratified organ of the Araneida. ‘lhe olfactory lobe is characterized
by the presence of numerous spherical or ovoid olfactory glomeruli.
The enigmatic appendage on the ventral surface of the brain is not
stalked ; its essential elements are elongated cells which differ from the
nerve-cells, and bound an excentric lenticular space which is occupied by
a mass of chitinous substance. There are no nerve-fibres, but elongated
cells, which are probably destined to facilitate the nutrition of the organ,
penetrate into the cerebral cortex.

5. Arachnida.

Malpighian Tubes and “ Hepatic Cells” of Araneina.*—Dr. A. B.
Griffiths and Mr. A. Johnstone have examined the Malpighian tubes and
hepatic cells of Tegenaria domestica; the secretion of the former was
found to yield uric acid, which was found in combination with sodium;
no urea, guanin, or calcium phosphate could be detected in the secretion.
The chemical tests applied to the secretion of the so-called liver show
that this organ in the Araneina is similar in its functions to the pancreas
of the Vertebrata.

Anatomy of Atax ypsilophorus and A. Bonzi.j—Dr. P. Girod has
examined the anatomy of these Hydrachnids, parasitic in Anodonta and
Unio. There are three pairs of buccal glands ; into the stomach there open
two large lateral czeca and one larger superior or cephalic cecum. The
excretory organ lies dorsally to the stomach and is Y-shaped; there is
no terminal intestine, and no anus; nor is there a cloaca common to
the rectum and the exeretory organ ; the latter opens by a special pore.

In the dorsal wall of the pharynx there are large rounded cells,
glandular in appearance ; the independent buccal glands are formed of
a delicate tunica propria and a single row of large cylindrical cells; the
protoplasm of these is homogeneous, and the nucleus is well marked.
The walls of the stomach and ceca are lined by a single layer of cells,
some of which are parietal and some secretory: the former contain

* Proc. R. Soc. Edinb., xv. (1887-8) pp. 111-4.
t Bull. Soc. Zool. France, xiv. (1889) pp. 107-10.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 747

greenish granulations and a large nucleus; they form groups of four
cells, which alternate with the large secreting club-shaped cells. These
are fixed to the wall by a filamentar extremity, and are supported by the
neighbouring parietal cells ; the free end dilates into an ovoid head, and
is supported by its neighbours, the whole forming a villosity which
projects into the cavity of the stomach. These giant-cells have a
granular protoplasm and a large basal nucleus; in addition there are
other masses in the interior, which vary with the cell under examination.
Sometimes there is a rounded body staining with carmine, or the body
may be larger and brownish; in other cases, there are two brownish
globes which appear to be formed by the transverse division of a single
body ; and in other cases there is a rounded group of brownish spheres
of which there may be as many as eight or ten. The excretory organ
has its wall lined by a layer of pavement-cells, filled with fine yellowish
eranulations ; these are set free by the breaking up of the cells, the
débris and nuclei of which are found among the free granulations.

Halacaride.*—Dr. H. Lohman has a monographic memoir on these
marine Arachnids. After detailing the history of our knowledge of
the group, the author discusses its morphological and anatomical
characters, and its systematic position; a convenient table is given, in
which the form of the body, the skeleton of the body, of the legs, and
of the capitulum, and other anatomical characteristics are enumerated
under the Prostigmata, peculiarities common to the Trombidiide,
Hydrachnida, and Halacaride, peculiarities special to the Halacaride,
peculiarities which they have in common with the Hydrachnida, and
those that they have with the Trombidiide. The conclusion arrived
at is that the Halacaride form a subfamily of the Prostigmata allied
to the Hydrachnida.

In the systematic portion the subfamily is defined, and the group
divided into four genera, of which Aletes and Agaue are new, the two
others being Halacarus and Leptognathus. The genera and species are
next systematically described ; of the latter there are twenty, ten of
which are new.

In the fourth division of his memoir the author deals with biological
results; these are treated of under the heads of distribution, and
peculiarities of mode of life; the latter is divided into: relation to
external influences, where we note that these creatures have a remark-
able want of sensitiveness towards cold; movements of the animals; and
relation to other plants and animals. In the fifth part the ova and the
developmental stages are described; there is a remarkable resemblance
between the larve and the imagines.

Structure and Development of Eye of Limulus.t—Mr. S. Watase
has a preliminary notice on this subject. When he compares his results
with those of Lankester and Bourne, he finds that they seem to have
overlooked the existence of one large ganglion cell in the centre of each
ommatidium of the lateral eyes, which, in the author’s opinion, is the
most important morphological element. By using the depigmenting
process they failed to make out the important differentiation into the
pigmented and non-pigmented parts existing in each rod-bearing cell, or
in the retinula. What they have called the intrusive connective tissue

* Zool. Jahrb., iv. (1889) pp. 269-408 (3 pls.).
+ Cire. John Hopkins Univ., viii. (1889) pp. 34-7.

748 SUMMARY OF CURRENT RESEARCHES RELATING TO

cells in the lateral eyes are the exceedingly elongated ectodermic cells,
each with its own nucleus, which closely indent the outer parts of the
rod-bearing cells. The entire structure of such elongated cells can only
be brought out by maceration of the retina, for sections are necessarily
misleading. The similarly named cells in the median eyes are also five
ectodermic cells not derived by secondary migration from the mesoderm.
The number of retinula-cells in the ommatidia of the lateral eyes is not
constant, but very variable. ‘The axial cavity inclosed by the rods, and
by the rhabdom, is not empty, but is occupied by the axial process of the
central ganglion cell.

«. Crustacea.;

Senses and Habits of Crustacea.*—Mr. W. Bateson, in the course of
his investigations on the perceptions of fishes, has made some interesting
by-observations on Crustacea. All in the tanks at the Plymouth
laboratory, except Carcinus mznas and Portunus depurator, are more
active by night than day, and many rarely come out by day at all.
Excepting the shrimps, nearly all the individuals of the other forms
observed have each its place to which it retires when morning comes,
and in which it remains during the whole day. ‘To the shrimp it is of
paramount importance to know the difference between night and day, for
it is not safe for it to hunt till darkness comes. Strangely enough it
seems that this knowledge is not obtained by the eyes, or at all events
not entirely through them, for there is no observable difference when |
the eyes are extirpated. Prawns, shrimps, and others find their food
almost exclusively by scent, but they do not seem to haye a very accurate
knowledge of the direotion of it; it is not even certain that they can see
each other. In some cases the eyes were observed to be particularly
sensitive to shadows. ‘Though it seems probable that the sense of smell
is by the antennules in shrimps, at any rate, it is not exclusively so,
for a shrimp with no antennules will hunt if a piece of worm be put
very near it.

A very interesting description is given of the method by which
certain crabs fasten pieces of weed and so on to their backs and appendages.
The crab takes a piece of weed in his two chelz, and neither snatching
nor biting it, deliberately tears it across as a man tears paper with his
hands. He then puts one end of it in his mouth, and, after chewing it
up presumably to soften it, takes it out and rubs it finely on his head
and legs until it is caught by the peculiar curved hairs which cover
them. The whole proceeding is most human and purposeful. The
various substances used are nearly always symmetrically placed on
corresponding parts of the body. Curiously enough not only are all
these complicated processes gone through by night as well as by day,
but a Stenorhynchus cleaned and deprived of sight will immediately
begin to clothe itself again with the same care and precision as before.

Function of Spines of Crustacean Zocee.{—Mr. W. F. R. Weldon,
by comparing the behaviour of such zocee as have long spines and of
those that are devoid of them, has been led to suggest a function for
these organs. A larva that has them swims in an absolutely straight
line towards the light, moving with great rapidity, and neither changing
direction nor losing equilibrium during @ journey of several feet. Larvee

* Journ, Marine Biol. Assoc., i. (1889) pp. 211-4. t+ T.¢, pp. 169-70 (I pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 749

without spines move towards the light in a very different manner ; all
forward movement is spiral and so indirect, an is frequently impeded
by somersaults, which appear to be involuntary ; after each of these the
zocea will hang for a moment vertically in the water, as if to recover its
sense of direction.

Celom and Nephridia of Palemon serratus.*—Mr. W. F. R.
Weldon commenced his investigations into the celom and nephridia of
Palzmon serratus by an attempt to repeat the experiments on secretion
recently described by Kowalevsky ; { the colouring matter is taken up
by the ccelomic and nephridial cells. Ifa prawn so stained be dissected
in strong alcohol, it will be seen that a blue area in the thorax is
connected by a deeply stained band of tissue with each nephridium ; the
blue area in the thorax is a sac which contains a clear fluid that is not
blood ; at its anterior extremity this sac gives off a pair of tubular
processes, one on each side, each of which passes downwards to open
into the urinary bladder of its own side. At its hinder end this sac is
in close contact with the gonad ; in other words, it is precisely similar
in all its relations to the celomic sac of a Mollusc.

The long narrow tube which connects the ccelom and the nepbridia
is beset with small ceca, and, from about its middle point, gives off a
long branched tube, which ramifies among the tissues of the base of the
eyestalk and of the first antenne. Similar tubules are given off from
the bladder. All there cecal appendages of the ccelomic system are
lined throughout by an epithelium which is perfectly characteristic.
‘Lhe spaces found by Lankester in the limbs of Astacus are possibly
derived from processes of the nephridio-ccelomic apparatus of the same
nature as those in Palemon. Mr. Weldon describes the structure of the
nephridial apparatus, and points out that the comparison so often made
between the glomerulus of the vertebrate kidney and the end-sac of the
crustacean green-gland is abundantly justified, each glomerulus being the
termination of a cecal outgrowth from a bent nephridial tube, which
communicates on the one hand with the body-cavity, and on the other,
either directly or indirectly, with the exterior.

Phosphorescent Infection of Talitrus and other Crustacea.t{—M.
A. Giard reports that he observed at Wimereux a Talitrus which was
so phosphorescent that he conld not accept the explanation of Quatrefages
that it was due to the presence of Noctiluce on the carapace. The
animal was, further, observed to be moving slowly. Microscopical
examination of an appendage showed that there were microbes in the
muscles, the structure of which had been considerably altered. Treated
with gentian-violet the microbe was seen to be a Diplobacterium 2 pw long.
Specimens of the same genus and of Orchestia littorea were injected with
these microbes, and the results surpassed the expectations of the author.
Of ten Talitri inoculated on the 6th of September, six commenced to
shine on the 8th, and on the 9th were as brilliant as the first specimen
observed. The action of the microbe does not seem to become attenuated
in successive generations, and is not modified by being inoculated into
Orchestia. ‘The light becomes so brilliant that two Talitri are quite
sufficient to illuminate the face of a watch. After some days the creature
dies, but its corpse remains phosphorescent for some hours; during the

* Journ. Marine Biol. Assoc., i. (1889) pp. 162-8 (3 pls). ¢ Ante, p. 368.
=~ Comptes Rendns, cix. (1889) pp. 503-6.

750 SUMMARY OF CURRENT RESEARCHES RELATING TO

course of the affection the power of the muscles becomes considerably
affected. Such examples as did not become phosphorescent after being
inoculated remained in perfect health. Other Crustacea, including the
common Crab, have been rendered phosphorescent by the inoculation of
this microbe.

Nervous System of Decapod Crustacea.*—M. L. Bouvier has
studied the Decapod Crustacea in an ascending order, and, as a result,
he comes to the conclusion that in a natural classification they would
not be all placed in this order. The fresh-water Astacide, for example,
appears to be a side branch of the marine Astacide; the Thalassinide
appear to be marine Astacide which have sheltered themselves in the
sand, and have ended by giving rise to the Paguride which take refuge
in shells and form the third term of another branch. So, again, the
Porcellanide, and perhaps the Anomura, are chiefly connected with the
Galatheide, and serve as the point of departure for the true Brachyura.
When the nervous system of the Macrura and Anomura is studied in
these three branches, we see that the nervous system presents its
maximum of condensation in the transverse direction in the “ Salicoques ”
which are placed at the base of the suborder; in the Astacide this
condensation is much diminished, especially in Nephrops; finally, in
the Porcellanids and Galatheidze, or the Paguride and Thalassinide,
this transverse dissociation becomes more and more marked. In the
Decapods, therefore, the concentration of the nervous system in the
transverse direction diminishes as we approach the Brachyura. ;

This law is absolutely exact if the abdominal chain is considered ; it
is only relatively so if the thoracic ganglia are studied. But this
difference can be easily explained. As the nervous system is dissociated
transversely, it has a tendency to condense longitudinally. In the
thoracic region, as compared with the abdominal, the ganglia are larger
and more closely approximated, and the connectives which unite them
are consequently shorter. And we may say, generally, that the conden-
sation of the nervous centres and connectives in the longitudinal direc-
tion is inverse to that in the transverse direction ; in the longitudinal it
increases aS we approach the Brachyura, and in the transverse it
diminishes.

These statements are not true of other Crustacea or Arthropoda; the
law is peculiar to the Decapoda, and may perhaps he of use in studying
the affinities of the constituent members of the group.

In passing from the macruran to the brachyuran forms, an abdominal
ganglion becomes part of the thoracic mass, the ganglionic chain
shortens and is placed in the thorax, and this reduced chain enters into
close contact with the centres of the thoracic region. The Galatheide
and Paguride are at the first, the Porcellanide at the second, and the
Crabs at the third stage.

“Liver” of Carcinus menas.t—Dr. A. B. Griffiths describes a
number of chemical investigations which seem to show that the so-called
liver of the crab is pancreatic in function.

Genital Organs of Thelyphonus.{—Herr J. Farnani has observed
that the male sexual organs of Thelyphonus asperatus undergo remark-

* Ann. Sci. Nat., vii. (1889) pp. 78-106 (1 pl.).
+ Proce. R. Soc. Edinb., xvi. (1888-9) pp. 178-81.
t Biol. Centralbi., ix. (1889) pp. 376-82.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 751

able changes during sexual maturity. The female organs consist of two
longitudinally folded saccular ovaries which extend throughout nearly
the whole length of the abdomen, and have a rather large cavity; the
dorsal side of the ovaries has no ovarian follicles; the second pair of
ovaries described by Blanchard could not be found. The walls of the
uterus are formed by a high glandular epithelium and a highly developed
porous chitinized intima; at the sides are the openings of two receptacula
seminis; near its hinder end the uterus forms two hollow, wing-like,
highly chitinized outgrowths, which serve for the attachment of the
muscles which are stretched vertically between the dorsal and ventral
wall. The male organs of immuture individuals consist of two tubular
testes, which pass anteriorly into very narrow vasa deferentia; these
open on the inner side of two reservoirs, which, again, are each con-
nected by a short efferent duct with the anterior end of an unpaired
cavity (uterus masculinus); this last opens into the genital cavity.
This uterus has an unpaired blind sac on its upper wall and a seminal
vesicle on each side; at its anterior end there is a circular chitinized
pad. In sexually mature animals the genital cavity alters somewhat,
numerous fulds appearing in its walls. The epithelium of the uterus
masculinus and its appendages becomes extraordinarily high, and the
chitinous investment much thicker; on its lower wall a groove becomes
distinctly noticeable, which extends from the opening of the blind sac to
the hinder end of the uterus, where it diminishes remarkably in breadth.
The reservoirs become much larger and fill up the anterior part of the
abdomen, while the walls between them become absorbed and an unpaired
reservoir is formed.

Transverse sections of sexually mature males reveal the presence of
tubular glands with very characteristic contents on the dorsal surface
of the whole abdomen ; these glands open into the unpaired reservoir.
‘The contents consist of small, rounded corpuscles with a central nucleus,
of a homogeneous material which, in spirit-specimens, becomes converted
into a yellow, hard, chitin-like mass, and of another homogeneous mass,
which in spirit often breaks up into rounded corpuscles. This body is
partly formed by the epithelial cells of the glands, which form two or
three layers; the inner part of each cell breaks up into five or more
pieces, and the final result is the formation of at least sixteen cor-
puscles, each of which contains a nucleus, and may therefore be regarded
as acell. Whether the other contents of the gland and of the reservoir
are products of the further metamorphosis of these cells cannot yet be
determined.

In conclusion, the author discusses, with figures, the homologies of
the various parts of the generative apparatus in the two sexes.

Lucifer-like Decapod Larva.*—Mr. G. Brook took in the tow-net
off the West Coast of Scotland a peculiar Decapod larva, which seems to
be unlike any which has yet been described; in general appearance it
is very like semi-adult forms of Lucifer, the development of which has
been worked out by Brooks. It differs, however, in having five pairs of
pereiopods, while Lucifer has only three in the adult and four in the
embryo; the telson is triangular in form, as in the normal Zoea of
Decapods; and the pereiopods and uropods are not developed till a
relatively much later period than in Lucifer. As it has an elongated

* Proc. R. Soc. Edinb., xv. (1887-8) pp. 420-3.

fe2 SUMMARY OF CURRENT RESEARCHES RELATING TO

neck, the author proposes to call it Trachelifer ; as to its affinities, he is
unable to speak definitely.

Life-history of Stenopus.*—Prof. W. K. Brooks reports on the
investigation made by Prof. F. H. Herrick and himself on the young of
this crustacean. The larve are very much larger than ordinary pelagic
larvee, and quite different from any known forms of Macrura. The chief
locomotor organs are the fifth thoracic legs, which are extremely slender,
as long as the entire body of the larvee, and ending in flattened elliptical
paddles, which are used as “sweeps” for rowing through the water.
Stenopus hispidus has a cosmopolitan range, and in structure, habits,
colour, and external appearance is one of the most highly specialized
of Crustacea ; its antenne are long and slender, and the acuteness of its
senses, together with its very remarkable alertness, the quickness with
which it perceives danger and the rapidity with which it escapes, have
undoubtedly aided it in holding its own whenever it has gained a footing
in a suitable locality. The upper surface of its body and limbs is
covered by a thorny armour of hooked spines, and as these all point
forwards, the attempt to swallow a Stenopus must be difficult and
painful. The length of its pelagic life is unquestionably an aid to its
wide dispeisal and to the discovery of new homes.

The eggs, which are very small, are laid at night, and during seg-
mentatiou the yolk remains undivided. At the time of its escape the
larva is a Protozoea, and its later history is of great interest, as it unites
features of resemblance to Lucifer, Sergestes, Peneus, and to the prawns
in general. At the time of hatching it has sessile eyes, locomotor
antenne, an enormous mandible, a deeply forked pleon, a long rostrum,

and a complete series of appendages as far as the first pereiopods; the

long hind-body has no appendage, and is only vaguely divided into
somites. Five or six hours after hatching it changes into a true Zoea,
much like that of an ordinary Macrouran.

In the Mastigopus-stage the eyes are greatly elongated, and the third
maxillipeds are extremely long, while the huge oar-like fifth pereiopod
of the preceding stage is reduced to a bud, and the fourth is also reduced
and has only two joints. As in the Sergestide, therefore, the last two
pairs of “walking legs” are shed after the Mysis-stage, to be again
reconstructed in the Mastigopus-stage. After several months this last
larval stage gradually assumes the adult form, the principal changes
being the shortening of the eyes and the reacquisition of the fourth
and fifth pereiopods.

Metamorphosis of British Euphausiide.|—Messrs. G. Brook and
W. E. Hoyle give an abstract of their observations on the metamorphosis
of British Euphausiide; the two most frequent forms are probably
Nyctiphanes and Boreophausia. They give for the first time an account
of one almost complete series of moults for one species. In their meta-
morphosis the Euphausiide stand almost alone, none of the later larval
stages being identical with the Zoea and other larve of Decapods. They
commence their life in the Nauplius condition, a type of larva frequent
in other groups. The larval formation of the antenne is retained until
the commencement of the Cyrtopia-stage, a feature which is not usual
among the Crustacea. The Calyptopis-stage, in which the compound

* Cire. John Hopkins Univ., viii. (1889) pp. 29-80.
+ Proc. R. Soc. Edinb., xv. (1887-8) pp. 414-20.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 7538

eyes, while undergoing development, are covered by an anterior expansion
of the carapace, is a remarkable one, which, so far as the authors know,
is only met with in one other group—an aberrant section of the Decapoda,
inclusive of Lucifer and others, where this condition obtains in the
Protozoea-stage.

Male of Phronima sedentaria.*—Prof. C. Chun has a note on the
male of Phronima sedentaria and observations on other species of the
genus. ‘Till quite recently this male had not been detected; it is very
probable that it makes no special house for itself, as does the female.
When they are sexualiy mature they develope the lower pair of antenne;
at the same time remarkable changes obtain in the appendages of other
segments ; the first joint of the flagellum of the anterior antenne becomes
enormous, and gets a thick covering of hairs. The tibia and metacarpus
of the fifth thorac’c appendage become wider, and on the metacarpus,
with its complexes of glands, of the oldest males three teeth become
apparent. By these and other changes in form the male of P. sedentaria
becomes very much like that of P. diogenes, as described by Claus,
though there are, it is true, several points of distinction. ‘The changes,
often rap'dly effected, in the appearance of Phronimids should make us
very careful of forming new species, and the author comes to the con-
clusion that P. atlantica Guérin-Ménéville and P. pacifica Streets are
young stages of P. sedentaria, while P. nove-zealandiz Powell and
P. borneensis Sp. Bate are adult stages of the same widely distributed
species,

Pelagic Copepoda of Plymouth.t—Mr. G. C. Bourne bas investi-
gated the Copepod fauna of the sea near Plymouth. He has been led to
this owing to the important part played by these minute Crustacea in
the change of material in the sea. Sixteen species were taken in the
tow-net, nine of which belong to the family Calanide. Onceea mediter-
ranea is here for the first time recorded north of the Mediterranean.

Female Generative Organs and Oogenesis in Parasitic Copepoda.{
—Dr. J. H. List has investigated the history of the female organs in
the Gastrodelphyidz, parasitic Copepoda intermediate between the
Notodelphyidez and the Siphonostomata. The ovaries and oviducts are
paired, there is a receptaculum seminis, and two canals with external
orifices. The formation of the egg-cells is effected in the Gastrodel-
phyide in the ovary which is filled with polygonal cells. When formed
the eggs are cut off in rows and pass into the oviduct where they receive
the yolk-masses. The eggs which are given off are replaced by others
formed in the anterior part of the ovary. The hinder part of the gonad
forms a kind of latent germinal layer, the function of which is to provide
cells for the anterior part. The ripe eggs, when set free, must pass the
receptaculum seminis to reach the maternal cavity, and they are fertilized
in it. In conclusion the author makes some observations on the similar
parts in the Notodelphyide.

Vermes.

Agamic Multiplication of Lower Metazoa.§—M. Maupas, who has
shown that, by methodical cultivations of ciliate! Infusoria indefinitely

* Zool. Anzeig., xii. (1889) pp. 378-82.
¢ Journ. Marine Biol. Assoc., i. (1889) pp. 144-52 (2 pls.).
{ Biol. Centralbl., ix. (1889) pp. 327-33.
§ Comptes Rendus, cix. (1889) pp. 270-2.
1889. 3 G

754 SUMMARY OF CURRENT RESEARCHES RELATING TO

prolonged, it is possible to produce senile degeneration, has made experi-
ments of a similar kind with some of the Metazoa which multiply
parthenogenetically and by budding. He has succeeded with some
species of Rotifers and oligochetous Annelids. Cyclogzena lupus, a car-
nivorous Rotifer, was nourished on Rotifer vulgaris, and was kept at a
temperature of 19-20° C. The ova were incubated in fifty-two or three
hours, and the young took sixty-five to seventy hours to mature their first
ovum, The maximum number of ovipositions was three a day. A
herbivorous species of Notommata was followed through twenty-two
uninterrupted generations from February the 6th to May the 18th; the
length of incubation of the ova was from forty-seven to forty-eight hours
at 15° C. and thirty-five at 19° C. Callidina vaga was followed through
twenty-nine generations. Of Oligocheta, Nais elinguis and Pristina sp.
were followed through a few generations only, but Chztogaster dia-
strophus through an uninterrupted series of forty-five generations. In no
one of these cases was sexual generation observed. The author is not,
at present, able to continue these investigations.

a, Annelida.

Polyodontes maxillosus.*—M. R. Saint-Loup has discovered near
Marseilles the large Aphroditid which is called Polyodontes mazillosus.
It is two metres long, and the diameter of the bidy near the head
20 mm.; further back it is only slightly attenuated. Various errors in
Claparéde’s figure of the external characters are pointed out. The.
proboscis, when extruded, is rather wider than the body; it has, in front,
four denticulated jaws, and the longest denticle is 4mm. ‘The cephalic
lobe carries the eyes at the end of two stalks, which are fused along their
line of contact; the projection of these organs is such that the worm can
see in front of it, even when the proboscis is protruded. The delicate
fringes which ornament the extremity of the proboscis are provided with
ultramarine, phosphoresceut granulations, which probably serve as a
lantern at night.

Notes on Oligocheta.t| —Mr. F. EH. Beddard states that in the sexual
form of Dero there are invariably two sete only in each of the ventral
bundles of the fifth segment; this worm appears to differ from other
Naidomorpha by the entire absence of ventral sete from the sixth
seoment; there isa single unpaired sperm-sac and egg-sac. In a new
large species of Perichzta from Borneo the spermatheca showed a marked
asymmetry. Some remarks are made on Dr. Rosa's recent criticism of
some of Mr. Beddard’s descriptions and systematic views.

Oligochetous Fauna of New Zealand.{—Mr. ¥’. E. Beddard points
out that, though all the species from New Zealand described by
Dr. Hutton are referred to the genera Lumbricus and Megascolex, most
belong to other genera and especially to Acanthodrilus. Fourteen
species, several of which are new, are enumerated in the present paper.
Rhododrilus is a new genus which comes nearest to Cryptodrilus and
Megascolides ; its atria are tubular, penial sete are present, and the
clitellum occupies segments xiy.-xvil. It would appear that the oligo-
chetous fauna of New Zealand differs markedly from that of Australia ;

* Comptes Rendus, cix. (1889) pp. 412-4.
+ Zool. Anzeig., xii. (1889) pp. 533-6.
t Proc. Zool. Soc. Lond., 1889, pp. 377-82.

ZOOLOGY AND BOTANY, MICROSUOPY, ETC. too

the characteristic form is evidently Acanthodrilus; Rhododrilus and
Neodrilus may be peculiar genera, and Deinodrilus has not been met
with elsewhere. The fauna of New Zealand presents a marked agree-
ment with that of Kerguelen, Marion Island, Patagonia, the Falkland
Islands, and South Georgia; so that with regard to the terrestrial
Oligocheta it seems permissible to speak of an “antarctic fauna.”

Anatomy and Histology of Phreoryctes.*—An abstract has been
published of Mr. F. E. Beddard’s memoir on this Oligochete. Among
the new points discovered by the author are the absence of genital and
penial sete; the clitelium occupies three to four segments, from the
tenth to the thirteenth; its epidermis is formed by a single layer of
cells, differing from those of the epidermis generally by their greater
length and glandular character. The nephridia of the sexually mature
worm commence in the sixteenth segment. In both vasa def-rentia and
oviduets the distal section is lined with a chitinous membrane, which is
continuous with that covering the body; they are in other respects
closely similar, and the position of the external orifice of the second
pair of vasa deferentia is intermediate between that of the first pair of
vasa deferentia and of the oviducts. The ova, which are, when fully
mature, of large size (one-half the diameter of the body), and loaded
with yolk-granules, undergo their development in egg-sacs which are
contained in the fourteenth to the sixteenth segments. ‘The ova and
ega-sics are more like those of the Tubificide than those of earthworms.
The author agrees with Vejdovsky in regarding Phreoryctes as the type
of a distinct family; this must be placcd between the earthworm and
the lower Oligocheta.

Polar Body Formation in Aulastomum.}—Herr G. Platner describes
the formation of the first polar body in Aulastomum gulo, with special
reference to the so-called achromatin substances. The centrosoma,
which he regards as a constant characteristic of the cell, is recognizable
as a definite body, but in the ripe ovum it is quite naked without
distinct ensheathing archoplasma. The polar body extrusion is intro-
duced by the division of the centrosoma, round the products of which
the yolk spherules become radially disposed. Soon, however, two
typical archoplasmic spheres are established round the two daughter
centrosomata. Contrary to Boveri’s opinion that the ripe ovum was
without centrosoma, Platner maintains that spermatozoon and ovum are,
as regards nucleus and division centres, exactly equivalent at the time
of formation of the first segmentation spindle.

8. Nemathelminthes.

Ovary and Oogenesis of Gordius.j|—M. A. Villot describes the
long ovarian tubes of the female Gurdius as consisting of a very delicate
outer layer of the nature of connective tissue, and a much thicker inner
layer formed of epithelial cells. The ova are not developed in the
cavity of the ovarian tubes, but in lateral diverticula which are an
essential part of them, and which are furmed by exogenous budding of
their wall. The contained ova are nothing but isolated and modified
epithelial cells. The ova do not pass into the cavity of the ovarian

Proc. R. Soc. Edinb., xvi. (1888-9) pp. 117-9.
Arch. Mikr. Anat., xxxiii. (1889) pp. 204-16 (1 pl).
~ Comptes Rendus, cix. (1889) pp. 411- z.
342

“+ *

756 SUMMARY OF CURRENT RESEARCHES RELATING TO

tube until they are mature, and this passage is the natural consequence
of their development, increase in size, reciprocal pressure, and the
elasticity of the wall of the ovigerous diverticula.

The fatty degeneration of the embryonic cells of the parenchyma
which furnish the necessary food for the generative products is much
more extensive in the female than in the male. In addition to the
circumintestinal cavity, a cavity appears in the dorsal middle line; the
complete degeneration at the time when the ova are deposited is very
marked. The parenchyma does not become regenerated, and does not,
as Vejdovsky supposes, form fresh gonads. Gordius reproduces only
once in its life, and the females, shatterel by oogenesis, die soon after
they have deposited their eggs.

Life-history of a Free Nematode.*—M. R. Moniez has made a
study of the metamorphosis and migration of Ehabditis oxyuris. After
the young have acquired a certain size, they fix themselves to various
Acari, and particularly to Holostaspis marginatus, in considerable
numbers; sometimes, indeed, there are as many as sixty worms on one
Acarid. The young Rhabditis secretes a large chitinous plate, to which
it is suspended by a short pedicel; the tissues and organs are detached
from the skin, which becomes altered in character, though remaining
perfectly transparent; its e'ements fuse, and the refractive granules
which mark the rudiments of the reproductive organs disappear. ‘There
is thus formed an ovoid bedy which is much smaller than the larve
at the expense of which it was formed, is completely detached from,
its old skin, and has the digestive tube in the form of a narrow longi-
tudinal cleft.

From the commencement of metamorphosis a long tail begins to
appear; in time the new larval form breaks away from the old one.
The author has not yet been able to trace the further history of the
second larva. i

Filaria medinensis in Animals.t—Prof. A. Raillet points out that,
although Filaria medinensis is generally considered a human parasite
it is found in other Mammals. such as the Dog, Horse, Cow, and Jackal.
Though the pathological conditions which it determines are much the
same, it does not produce the painful complications seen in Man.

Pseudalius alatus.t—Dr. O. v. Linstow gives a description of the
form which, in 1848, Leuckart called Strongylus alatus ; the new account
differs considerably from the original, which was drawn up when our
methods of research were less perfect. The author remarks that the
six known species of the genus appear to flourish where there is an
abundant supply of oxygen, since they live in air-containing organs or
in the blood-vascular system; thus P. alatus is found in the pharyngeal
cavities, mouth, and Eustachian tube of Monodon monoceros ; four species
are found in the air-cavities and blood-vessels of the Porpoise, and
P. ovis pulmonalis in the bronchi of sheep.

Spiroptera alata, a new Nematode found in Rhea americana.§—
Dr. F. Zschokke found in the crop of a Rhea americana a male specimen
of Spiroptera. Apart from the size, it is distinguished from S. uncipenis,

* Conptes Rendus, cix. (1889) pp. 506-7.

+ Bull. Soc. Zool. France, xiv. (1889) pp. 73-6.

{ Proc. R. Soc. Edinb., xvi. (1888-9) pp. 15-7 (1 pl.).

§ Centralbl, f. Bakteriol. u. Parasitenk., vy. (1889) pp. 792-4.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. reay |

which was found by Molin in the same host, by the presence of wing-
like appendages which project from the head. There are also minor
differences both at the anterior and posterior ends. The animal is about
30 mm. long and about 1 mm. broad, and a minute description is given
of it.

Vitality of Trichine.*—M. P. Gibier finds that if small fragments
of trichinized flesh be exposed to a temperature of 20 or 25 degrees
below zero, they exhibit a characteristic activity such as is not seen in
trichine of salted meat before refrigeration.

y. Platyhelminthes.

Fresh-water Turbellaria.t—Dr. E. Sekera first d'scusses the sexual
relations of Microstoma ; sexual and asexual reproduction may be seen in
the same individual, and at the same time. The gonads are found both
in separate individuals and in the zooids, and are generally of one sex
only; in rare cases, however, hermaphroditism obtains, and this is a
condition which the author is inclined to regard as atavistic ; in such
cases the male gonads are developed before the female.

The genus Stenostoma should be removed from Graff's family of the
Microstomide, and form an independent group of Stenostomide, in
which should also be placed the genera Catenula and Rhynchoscolex. In
the third part of his work the author gives an account of some new or
little known species—these are Mesostoma hirudo Schmidt, Vortex
coronarius Schmidt, V. paucispinosus and Bothrioplana alacris spp. un.

Microstoma papillosum.{—Dr. L. Bihmig finds that in Microstoma
gapillosum the genital products are produced in two (sexual) indi-
viduals; that the colonies are moncevious, and that, in all proba-
bility, asexual reproduction ceases during sexual reproduction, and
that chains, the individuals of which possess genital organs, consist of
two individuals of the first order. Sections must be made to determine
whether the separate individuals of the chain are unisexual or herma-
phrodite.

Notes on Entozoa.S—Signor F.S. Monticelli has notes on some new
and rare species in the collection of the British Museum. Distomum
microporum is a new species found in Plagyodus ferox ; Trematoda have
not before been observed in the Plagyodont na. Pelichnobothrium
speciosum sp. n., from Alepidosaurus ferox, is the type of a new genus in
which the head has a large pyramidal haustellum, truncated anteriorly
and provided with a well-developed terminal sucker; there are four
bothria which have the form of a basin, and are completely adherent to
the head; each has an accessory scrobiculiform sucker, and they are
arranged in couples on either side of the head. Teenia falciformis Baird
was, with a query, said to have an unarmed rostellum ; Signor Monticelli
finds that it is armed with eight very slender and long hooks of charac-
teristic form. Similarly, Tzenia calva Baird from the grouse (Lagopus
scoticus) has not an unarmed rostellum, but one which is provided with
a small crown of very numerous minute hooks. JT’. bifaria, enumerated

* Comptes Rendus, cix. (1889) pp. 533-4.

+ SB. K. Bohm. Gesell. Wiss., 1888 (1889) pp. 304-48 (G4 pls ).
{ Zool. Anzeig., xii. (1889) pp. 479-83.

§ Proce. Zool. Soc. Lond., 18359, pp. 821-4 (1 pl.).

758 SUMMARY OF CURRENT RESEARCHES RELATING TO

in Baird’s Catalogue as a species of Von Siebold’s, does not appear to
have ever been described ; the author now gives an account of it.

Helminthological Notices.*—Dr. Sonsino has given an account of
the entozoa of the Long-eared Fox (Megalotis cerdo) of Egypt. Among
them are Tenia echinorhynchoides sp. n., on the rostellum of which there
are twelve to sixteen transverse rows of hooks similar to those of T.
cucumerina ; Echinorhynchus pachianthus, which is much smaller than
E. gigas; Physaloptera cesticillata and Heterakis crassispiculum spp. nn.
A larval form of cestode found in the subcutaneous connective tissue of
the Jackal (Canis aureus) is suspected to be the young of Bothriocephalus
Manson.

Tristomum elongatum.|—Prof. M. Braun makes some additions and
corrections to v. Baer’s description of this Trematode. The excretory
organs open by a large flask-shaped vesicle in the region of the pharynx ;
numervus fine anastomosing vessels may be easily seen in the anterior
transparent parts of the body, but ciliated infundibula could not be
detected. All the vessels are, on each side, collected into an anterior
and posterior primary trunk, which open separately into the base of the
excretory vesicle. In front of the pharynx the brain may easily be seen,
as well as four thick nerve-trunks, which soon break up into anastomos-
ing branches and supply the very mobile anterior part of the body;
posteriorly there arise two thick trunks, which soon bifureate and can be
followed to the hinder end, where they pass into the sucker. There are
two larger and two smaller black eyes on the brain. Numerous yolk- «
follicles are to be found among the enteric appendages ; they pour their
secretion into two anterior shorter, and two posterior and longer yolk-
ducts; the latter unite and pass into the yolk-reservoir, which lies in
front of the ovary; from this a canal takes a somewhat winding course
to the uterus. In front of this last lies the cirrus, the nature of which
was misunderstood by von Baer. No vagina could be found in the fresh
animal, and the author doubts whether one is present. Further, histo-
logical, details are promised.

5. Incertee Sedis,

Anatomy of Dinophilus.{—Mr.8. F. Harmer gives an account of the
anatomy of Dinophilus teniatus, a new species found at Plymouth.
With regard to the affinities of the genus, the author agrees with pre-
vious observers, and especially Weldon, as to its archi-annelid relation-
ships. He points out that the presence of two rings of cilia on each
seoement is common to the new species and to Protodrilus leuckarti.
There is a close resemblance in the nervous systems of these two genera,
save that that of Dinophilus (like that of Histriobdella, an undoubted
archi-annelid) is segmented. The nephridia of D. teniatus closely
resemble those of Protodrilus, as described by Hatschek. In many of
its features Polygordius ditters from Dinophilus far more than does
Protodrilus, but, on the other hand, Histriobdella is probably more
closely related to Dinophilus than is Protodrilus. Although it seems so
clearly an archi-annelid, we may agree that Dinophilus gives evidence of
having been derived from Platyhelminth-like ancestors. In the per-

* Arch. Ital. Biol., xii. (1889) pp. 295-6.
{ Zool. Anzeig., xii. (1889) pp. 433-4.
$ Journ. Marine Biol. Assoc., i. (1889) pp. 119-45 (2 pla,).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 759

sistence of the prw-oral ring of cilia, probably of the head-kidneys, as
well as in the general characters of the enteric canal, the adult Dino-
philus may be considered to remain in a condition which is practically
that of a trochosphere.

Rotifera.*—Dr. C. T. Hudson has issued a supplement t the well-
known work by himself and Mr. Gosse on the Rotifera. He gives in it
a description of every known foreign species, as well as of such British
ones as have been discovered since 1886, More than 150 species are
here described, and more than 40 doubtful or imperfectly described
forms are briefly discussed and occasionally illustrated.

Echinodermata.

Homologies within the Echinoderm-phylum.f—Dr. R. Semon com-
pares the several organs of the representatives of different orders of the
Echinodermata with one another. Some of them he regards as com-
pletely homologous—such are the enteric system, the enteroccel, the
water-vascular, and the nervous systems. Other structures are merely
analogous or homoplastic, as are, for example, many parts of the skeletal
apparatus. Other structures are neither homologous nor analogous, for
the common organ from which they were derived was of so indifferent a
nature that from it there have been independently developed in the
various classes organs which are sometimes similar and sometimes very
different. Under this head may be placed the musculature ; it is in all
cases derived from the typical dermomuscular tube, but presents great
differences in Holothurians, Starfishes, and Sea-urchins; here, too, come
parts of the water-vascular apparatus and of the nervous system of
Holothurians. If we suppose that the primary tentacles of Holothurians
correspond to those of the other classes, the water-vessels of the body
and the nerves of Holothurians have only a general and not a special —
homology with those of the other classes; if, on the other hand, we
regard the secondary tentacles of Holothurians as strictly comparable to
those of the other classes, then the primary tentacles have only a general
homology.

In the present state of our knowledge it is impossible to decide how
far the blood-vascular systems of the various classes are generally or
specially homologous or merely homoplastic; the dorsal organ has
probably a general homology.

Comparative anatomy indicates that the classes of the Echinodermata
were certainly derived from a common stem-group, but this, in its
general structure, exhibited somewhat indifferent characters, and the
various Glasses have diverged in their development from this point of
origin. The history of development appears to support this view. The
author congratulates himself that the views he has already expressed
have been confirmed by the investigations of the Drs. Sarasin.

The simplitied Synapta of the Sarasins is not very different to the
pentactula-like stem-form of the author; bnt they are not quite correct
in speaking of this as a Holothuria-stage.

Neumayr is also inclined to recognize a very early divergence of
the classes from simple stem-forms, but he regards the Echinoids and

* <The Rotifera or Wheel Animalcules,’ by C. T. Hudson, assisted by P. H.
Gosse. Supplement, London, 1889, 64 pp., 4 pls.
+ Morphol, Jahrb., xv. (1889) pp. 253-307.

7TE0 SUMMARY OF CURRENT RESEARCHES RELATING TO

Asterids as having been longer and more closely connected than, in the
opinion of Dr. Semon, the facts warrant. It does not seem to be
justifiable to identify the Cystids with these indifferent stem-forms. We
know nothing of their internal organization, and what we do know of
their skeleton does not support this view.

Embryology of Muelleria Agassizii. *«_Mr. C. L. Edwards has
investigated the development of this common Holothurian. The eggs
are quite opaque, of a brownish colour, and surrounded by a struc-
tureless zona radiata. Three polar globules, one considerably larger
than the other two, are extruded; the segmentation is total and nearly
regular ; a gastrula is formed on the beginning of the second day. The
embryo ‘becomes ciliated, and during the next day appears to pass through
an abbreviated auricularia-stage. By the fifth day the embryo developes
five oral tentacles and the beginning of the calcareous skeleton of the
larva, while green pigment-spots also appear. On the fifth or sixth day
the embryo, by means of its tentacles, breaks the tough investing coat
and begins to creep about. On the sixth day an ambulacral foot arises
at the posterior end and grows so rapidly that, on the eighth day, it
exceeds the oral tentacles in length. On the eleventh day a second, and
on the fourteenth a third ambulacral foot appears, and in such positions
as to differentiate the ventral surface.

In the meantime the calcareous rods have been getting longer and
branching; the branches anastomose to make rosette forms, while from
the centre of each of these rosettes arise two vertical spines, which are at
first free and are then joined to one another by cross-bars. The intestine
is plainly visible as an orange-red body, and the anus is guarded by two
valves, formed of fused calcareous rods, running longitudinally to the
body, which wave, fan-like, from side to side with the cloacal respiratory
moyements. Quite early a circulation of granules and corpuscles may
be noted in the ambulacral system.

By the thirtieth day a fourth ventral foot has become developed, and
the budding fifth appears, while, near to the base of the oral tentacles,
dorsally and laterally, there appear respectively the beginnings of a pair
of ambulacral feet. By the forty-second day a fifth ventral foot has
partially developed, and two additional pairs of lateral feet have
budded from the middle and posterior portion of the sides.

In the first day after hatching the sucking discs of the oral tentacles
have shown the beginning of division into two lobes; somewhat later
these each divide into two lobes, giving the basis for ‘the dichotomous
division of the tentacles in the adult.

These Holothurians are not difficult to rear, and some were under
observation for eighty-four days.

Boring Sea-Urchins.{—Herr G. John has an essay on the somewhat
vexed question of the manner in which sea-urchins bore into rocks. He
comes to the conclusion that the cavities which they inhabit have been
formed by themselves, and that they produce them by means of their
masticatory apparatus, which is aided to some extent by their spines, as
the creatures move round and round. ‘These cavities are formed as a
protection against the action of the sea. ‘The calcareous alge which
cover the rocks inhabited by the sea-urchins are deposited mechanically,

* Cire. Jolin Hopkins Univ., viii. (1889) p. 37.
{ Archi. f. Naturgesch., ly. (1889) pp. 268-302 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 761

and have no influence on the chemical character of the surface of the
rocks, and they cannot therefore be supposed to have any connection
with the origin of the Echinus holes.

Saccular Diverticula of Asteroidea.*— Dr. A. B. Griffiths and
Mr. A. Johnstone find that the saccular diverticula are pancreatic in
function ; the same tests were applied as to Tegenaria.t

New Ophiurids.{—Mr. J. E. Ives describes a new genus of Ophiurids,
which he calls Ophioncus (O. granulosus sp. n.); it is the only genus,
except Ophiura, that has the genital slit divided; but it differs in having
the inner opening larger and not smaller than the outer one. In general
characters and in structure of its arm-bones the new genus seems to be
nearest to Ophiozona.

Ceelenterata.

Chun’s Celenterata.s—Prof. C. Chun has commenced a new edition
of such of Bronn’s Klassen u. Ordnungen as dealt with the Coelenterata.
The first part deals only with the history of the group.

Occasional Presence of a Mouth and Anus in Actinozoa.|| —Mr.
H. V. Wilson calls attention to the occasional occurrence of actinians or
corals in which there are permanently separate openings into the gastric
chamber. If the theories of Sedgwick and E. B. Wilson are correct, this
is precisely the variation which must have occurred in the ancestral
radiate, and to which bilateral animals owe their existence. Among
many examples of the large actinian which is called Cereactis bahamensis,
one had the free lips of the csophagus grown together along the
sagittal axis, except where the sagittal furrows opened into the gastric
chamber. Here there were two small circular openings. The concres-
cence was an actual and perfect union of tissue, and the animal was an
adult of normal size, and thoroughly healthy. The union of the lips
must, however, have affected its feeding, for it must have made it
impossible fur the creature to eat small gastropods, such as are often
found in the gastric chamber of these anemones. A similar variation
was observed in a single swimming larva of the coral Manicina areolata.

Arrangement of Tentacles in Cerianthus. { —Dr. P. Fischer points
out that the view that the tentacles of Cerianthus membranaceus vary in
number, but are always paired, is incorrect, for there is always an odd
number of them; this is due to the presence of an unpaired tentacle,
which is constantly found near one of the angles of the mouth, and
serves to determine the ventral side of the animal. He finds that the
marginal tentacles of the first cycle correspond to the buccal tentacles
of the second; that the marginal tentacles vf the second correspond to
the buccal tentacles of the third, and that the marginal tentacles of the
third cycle correspond alternately to the buccal tentacles of the first and
third cycles.

The bilateral symmetry of Cerianthus is demonstrated by the
arrangement of the buccal tentacles, while, on the contrary, the marginal
tentacles generally indicate a radial symmetry. On the other hand, the

* Proc. R. Soc. Edivb., xv. (1887-8) pp. 114-5. + See ante, p. 746.
+ Proc. Acad. Nat, Sci. Philad., 1889, pp. 143-6.

§ Bronn’s Klassen u. Ordnungen, ii., 2, Coelenterata (1889), pp. 1-48.

|| Cire. John Hopkins Univ., viii. (1889) pp. 37-8.

{ Bull. Soc. Zool. France, xiv. (1889) pp. 24-7.

762 SUMMARY OF CURRENT RESEARCHES RELATING TO

existence of an unpaired ventral tentacle, either marginal or dorsal, the
form of the mouth, the arrangement of the mesenteric septa, and the
prolongation of two of these septa as far as the pedal pore, together with
the mode of development of the embryo, furnish an accumulation of
proof in favour of that bilateral symmetry of Cerianthus which has
already been urged by Haime.

Madrepore Corals from Ceylon.*—Dr. A. Ortmann describes the
collection of madrepore corals, brought by Prof. Haeckel from Ceylon,
and has been led to some new conclusions in regard to the systematic
relations and morphology of these Anthozoa. Of Athecalia, ten new
species are described ; of Pseudothecalia, two ; of Euthecalia, one; while
a great number of forms, previously recorded, are briefly diagnosed. As
will be seen from these names, the investigator follows Heider’s division
of the Madreporaria, and distinguishes the three orders as follows :—

|
ATHECALIA. | PSEUDOTHECALIA. EUTHECALIA.
Theca 0 | 0 compact.
Synapticula | present, sometimes | meeting in a false | 0
forming a ccenen- | wall, otherwise ab-
| chyma or a porous | sent. |
wall.

Ceenenchyma | from united synap- from costal-ccenen- absent, or compact
ticula, or absent. | chyma, or absent. and not distin-
| | guishable from the
| wall, or forming a
vesicular exotheca.

Bepta those of adjacent | those of adjacent not evalescing, not (?)
calices coalesce, or | calices meet, or are | trabecular, compact,
loce themselves in | prolongedaskeeled margin entire.

the conenchyma | ribs over the false |

or porous. wall, wall, trabecular, |

trabecular, porous | compact, rarely |

or compact, toothed.| somewhat porous |

above, toothed. |
}
Traversals, | present or absent. usually numerous. present or absent.
Floors or
Dissepiments
Extra material 0 0 sometimes a solid
mass of lime in the
calyx.

The Athecalia are then divided into Thamnastreacea, Madreporacea,
and Fungiacea ; the Pseudothecalia include especially the Astreine and

* Zovl. Jahrb., iv. (1889) pp. 493-590 (8 pls.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 763

Echinoporineg, most of Duncan’s Astreide, and all the Lithophylliacea ;
while the Euthecalia comprise apparently all the genera of Oculinida,
many if not all Turbinolide, Eusmiline, and Euphylloide.

After a chapter on the nomenclature of coral structures, Dr. Ortmann
proceeds to discuss the formation of the coral stock or colony, with
special reference to Fungia, which he regards “as a true stock with
division of labour such that in the centre there is situated a large, radiate
person with an oral aperture, and round about this numerous smaller
individuals, of each of which only a tentacle persists.”

A discussion of the radiate symmetry and the development of septa
leads on to the question of the Tetracoralla, in regard to which Ortmann
urges (1) that there is no essential difference between them and Hexa-
coralla, (2) that bilateral corals are predominantly solitary forms,
(8) that since Paleozoic times the bilateral type has been on the wane,
and that in the development of the Hexacoralla the bilateralness is
pushed back to a very early embryonic stage, (4) that the Hexacoralla
have sprung directly from Tetracoralla.

Milne-Edwards’ law of the increase of the septa is modified into the
following :—In 6-radiate corals, the number of septa grows in such a
way that new septa arise throughout where there is room for them. If
a coral has a more or less regular shape, then the new septa conform,
but always in the closest connection with the external form of the coral,
and directly explicable in relation to the same.

The author thinks that twelve (certainly not six) is the fundamental
number for Hexacoralla, and finally sums up with a few modifications
his previously published conclusions on the general pedigree of the
Hexacoralla.

Bunodes and Tealia.*—Messrs. G. Y. Dixon and A. F. Dixon have
some notes on Bunodes thailia, B. verrucosa, and Tealia crassicornis.
The first of these resembles Tealia bunediformis in the possession of
‘endodermal saccules,” the form and arrangement of the mesenteries,
- and the nature of the circular muscles. In order to ascertain the generic
and specific value of these characters the other two species were investi-
gated, and the conclusion was arrived at that if B. thallia and T. bunodi-
formis are not identical, they are at least more closely allied to each
other than to either of the two other forms with which they have been
compared. According to the present systematic arrangement of Hertwig,
an adult Tealia crassiformis with its parts in multiples of five, an adult
Bunodes verrucosa with its parts in multiples of six, and an adult B. thallia
with no apparent numerical symmetry, are all relegated to the same
family.

Edwardsia-Stage in Free-swimming Embryos of a Hexactinian.}—
Mr. J. P. McMurrich, in studying some swimming embryos of Aulactinia
stelloides, found that they passed through a stage with e'ght mesenteries,
the longitudinal muscles of which were arranged as in Kdwardsia. The
hexactinian arrangement is derived from this by the formation of the
fifth and sixth pairs of mesenteries, which make their appearance respec-
tively between the dorso-ventro-lateral and the ventro-lateral and ventral
directive mesenteries.

* Scient. Proc. R. Dublin Soc., vi. (1889) pp. 310-26 (2 pls.).
~ Cire. John Hopkins Uniy., viii. (1889) p. 31.

764 SUMMARY OF CURRENT RESEARCHES RELATING TO

New Type of Dimorphism found in Antipatharia.*— Mr. G. Brook
reports that a study of the ‘Challenger’ collection of Antipatharia has
shown that some of the genera are dimorphic, while others are not. In
Antipathes the zooids are of the normal sextentaculate type, but show a
tendency to become elongated in the transverse axis ; in Parantipathes
the transverse mesenteries become enormously clongated, so that the
length in the transverse axis is three or four times that in the sagittal ;
this elongation has the effect of carrying the “lateral” tentacles further
away from the stomodzum, so that they now appear as three pairs some
distance apart; in P. larix the peristome becomes somewhat depressed
on each side of the oral prominence, so that the zooid presents indications
of a division into three lobes: one central, containing the stomodeum
and the proximal ends of all the mesenteries, and two lateral, which
contain the greater part of the transverse mesenteries; it must be re-
membered that the reproductive elements are borne on the transverse
mesenteries only, and in Parantipathes they are confined to such portions
as are situated within the lateral lobes. In Schizopathes the three lobes
of the zooid become separated from each other by a further depression
in the peristome and by the formation of a mesogleal septum; each
lobe of the primitively simple zooid thus becomes separated from its
neighbour, and in Schizopathes may be considered as dimorphic forms.
The middle one, which contains the stomodeum, may be called the
gastrozooid, while the lateral, which contain the two reproductive organs,
may be distinguished as gonozooids. In Bathypathes the differentiation
is carried a step further, for the individual zooids are separated from
one another by considerable intervals, though still connected together
by axial prolongat ons of their ceelentera.

The author proposes to divide the Antipathide into the two sub-
families of the Antipathinz and the Schizopathine ; Parantipathes, which
is placed in the former, being the link between them. This is the first
observed case of dimorphism of this kind in the Zoantharia generally,
and is, further, of interest, as being brought about by the division of one
zooid into three, and not by a specialization of different individuals; it
differs, therefore, essentially from the dimorphism of Madrepora Durvillei,
or that of Hydroids.

Organization and Phylogeny of Siphonophora.t—Prof. C. Claus
has a somewhat severe review of “HE. Haeckel’s so-called Medusome-
theory.” { He points out that eleven years ago he showed that the
Medusa-theory and the Hydroid-theory are not as irreconcilably opposed
to one another as Haeckel asserts ; this statement is supported by various
quotations. It is urged that the Medusome-theory is a new variety of
the Medusa-theory, but it loses probability in the same degree that
Haeckel’s new special assumption appears arbitrary and unfounded.
The proposed new classification, the basis of which is the assumption of
a special stem-form for the Discoidez, which may be esily and naturally
derived from the Physophoridz, will have to be rejected as a novelty by
no means justified by the state of the case. Prof. Claus raises similar
objections to the many new names proposed and to the new nomenclature
for the parts and appendages of the Siphonophora. He thinks that the

* Proc, R. Soc. Edinb., xv. (1888-9) pp. 78-83.
t Ann. and Mag. Nat. Hist., iv. (1889) pp. 185-98.
} This Journal, 1888, p. 741.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 765

special descriptive part of Haeckel’s work is much more valuable than
the general, though too many genera have been proposed, and that there
was no need to make a special order for the remarkable deep-sea genera
Stephalia, Auralia, and Rhodalia.

Porifera.

Monograph of Horny Sponges.*—Dr. R. v. Lendenfeld has pub-
lished a monograph of the Horny Sponges; there are 1641 (not always
correct) bibliographical references. In investigating sponges it is re-
commended that for the study of the canal system longitudinal sections
perpendicular tv the surface should be made, as they give a much clearer
insight into the structure than any others; some of the sections should
be as much as 0°3 mm. thick, as particularly thin sections are generally
useless for the purpose of studying the canal system. It is important to
prepare portions of the skin, and the skeleton should always be studied
both dry and wet. Skeletons macerated in the sea and thrown up on
the beach are, as a rule, superior for the purpose of studying the rough
anatomy of the skeleton to those artificially prepared. In the general
accounts of the genera the author ordinarily gives a historical intro-
duction, and accounts of shape and size, colour, surface, rigidity, canal-
system, skeleton, histology and physiology, affinities of the genus,
statistics of the species, key to the spec'es and varicties, and distribution.

The author does not consider that the Horny Sponges form a natural
order, but that different groups of them are structurally allied more
closely to other groups of not horny sponges than to each other. An
artificial group, of new extent, that of the Monoceratina, is formed for
the Aulenide, Spongidee, and Spongelide, each of which represents a
natural group allied to a family of siliceous Cornacuspongiz.

In the synthetical portion of his work the author discusses the mor-
phology, histology, and physiology of Sponges, their embryology, and
the homology of the embryonic layers; he also enters into the question
of the phylogeny of the Sponges in general, discusses their systematic
position, and gives a system of Sponges.

The plates give photographic illustrations of the general appearance
of various Horny Sponges, and figures of preparations of chiefly the
skeleton and the canal-systems.

Metamorphosis of Larva of Spongilla.j—Herr O. Maas has inves-
tigated the development of Spongilla. He describes the young larve as
swimwing about by the active movement of their flagella, and as secking
the darker parts of the aquarium in which they were being studied. In
form they are distinctly ovate ; the ectoderm consists of high cylindrical
cells with elongated nuclei; the interior of the larva is too dense to
allow of much being made out. The larve become fixed at the anterior
pole, and their contour becomes much changed owing to the enlargement
of the surface; at the same time the whole ectoderm becomes flattened,
and in time the boundaries between the cells disappear. This flattening
of the ectoderm results in great changes in the form of the cilia, which,
at first closely packed, become in time widely separated. After this a
peculiar change occurs in the ectoderm; its sharp wavy boundaries
appear to be broken at various points; this is due to the ectoderm at

* London, for the Royal Society, 4to, 936 pp., 50 pls., 1889.
t+ Zool, Anzeig., xii. (1889) pp, 483-7.

766 SUMMARY OF CURRENT RESEARCHES RELATING TO

the apparently broken points becoming converted into an extremely thin
hyaline layer, which sends out pseudopodia-like processes. As a result
of all its changes, the ectoderm of the larva of Spongilla becomes
completely converted into the epithelium of the young Sponge.

Sections through young oviform larvee show that the so-called endo-
dermal nucleus is not an indifferent mass of tissues, but contains more
or less perfect flagellate chambers, as well as spicules and other meso-
dermal elements. The spindle-shaped cells which Goette describes as
lying immediately beneath the ectoderm were also found by Herr Maas
to be always separated from it by a layer of mesodermal cells. Sections
made after the larva has become fixed show this relation of parts very
distinctly.

Protozoa.

Biitschli’s Protozoa.*—Prof. O. Biitschli has brought to completion
the work on which he has been engaged for the last ten years. In
the presence of this great undertaking, so successfully completed, we
may be allowed to depart a little from the reserve which characterizes
the abstracts in this journal and offer him, in the name of general
biological as well as specially microscopical students, our congratula-
tions and thanks for this monumental work.

The pages which remain to be reported on treat of the Suctoria,
which are fully dealt with; to these there are appended a shoft notice of
Haeckel’s system of the Radiolaria published in 1887, a very interesting
postscript relating to the history of the work, a systematic index of names
extending over sixty columns, an index of authors, a useful note as to
the pages at which some general questions are discussed, and a few
corrections and additions.

Psychology of Protozca.t—Dr. G. J. Romanes reviews the two
works whose titles are cited below;{ of the first he declares that but
for the title-page he would have doubted the authorship of the work.
'The second is “charged throughout with the experimental work of a
physiologist, and with the analytical powers of a well-instructed mind.”
There does not seem to be any evidence at all of even the lowest degree
of mental life in any unicellular organisms. The Protozoa afford an
exception to the general rule that in excitable tissues the principal seat
of excitation is the kathode on closing and the anode on opening a
galvanic circuit. When a galvanic current is closed through a drop of
water containing a number of Protozoa, they will all begin to travel
rapidly and directly to the negative pole, and, if the current be left
closed for a few seconds, will all become congregated thereat. On now
opening the current they will all begin to travel towards the positive
pole, but then soon segregate. By using a movable kathode of harmless
material the Protozoa may be led about like a flock of sheep following
their shepherd. No evidence, but rather the contrary, was collected as
to the value of the nucleus as a co-ordinating centre of movements,
ciliary or otherwise, for unnucleated portions continue to exhibit all the
same spontaneous movements as the nucleated.

* Bronn’s Klassen u. Ordnungen, i., Protozoa (1889) pp. 1841--2035 (pls.
Ixxvi.-ix.). + Nature, xl. (1889) pp. 541-2.

t{ A. Binet, ‘The Psychic Life of Micro-organisms.’ ‘Translated from the
French (Chicago, 1889). Dr. Max Verworn, ‘ Psycho-physiologische Protisten-
Studien: expcrimentelle Untersuchungen’ (Jena, 1889).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 767

Method of Demonstrating Presence of Uric Acid in Contractile
Vacuoles of lower Organisms.*—Dr. A. B. Griffiths has been able, by
direct experiment, to show that’ at certain times the contractile vacuole
of the Prot»zoa performs the function of a true kidney. A number of
Amcbx were placed on a microscopic slide and covered by a thin glass
slip; alcohol was run in to kill them, and was followed by nitric acid.
The slide was gently warmed and ammonia introduced. In a few
minutes prismatic crystals of murexide, having a beautiful reddish-
purple colour, made their appearance. Similar results were obtained
with Vorticella and Paramecium,

Symbiosis of Algee and Animals.t—Prof. A. Famintzin states that
the Alga with which Tintinnus inquilinus is symbiotic, is not, as
previously supposed, an Hctocarpus, but a diatom belonging to the genus
Cheetoceros. It unites itself with a 1—5-celled colony of the diatom,
its envelope becoming completely welded with it. When the union takes
place at an early stage, the horns of the diatom frequently fail to
develope.

The yellow cells of the Radiolaria are identified by the author with
Zooxanthella extracapsularis and intracapsularis, the former only of which
is known to develope outside the host. In opposition to the statement
of Brandt, the author finds that the Radiolaria, especially Collozoum
terme and Spherozowm punctatum, live on the yellow cells not only
immediately before the formation of the spores, but at all times, im-
parting to them their golden yellow or rusty brown colour; and the
same is the case also with several Actiniz.

Holotrichous Infusoria.t—In the introduction to his description of
some Holotrichous Infusoria, Dr. W. Schewiakoff defines certain terms
which he uses. Very small forms are those which do not measure more
than 0°04 mm.; small, those not more than 0:07 mm.; of medium siZe,
those less than 0°12 mm.; the large are not more than 0°25 mm., and
very large those that are more, But these definitions are, of course,
conventional. Stiff Infusoria are those whvse bodies undergo no altera-
tion in form; elastic those which do not change of themselves but are
altered in consequence of some external pressure, on the cessation of
which they return to their former form. Flexible Infusoria have the
power of independently altering without making any noticeable change
in their general form; while contractile Infusoria are those which can
lengthen or shorten one dimension at the expense of others, and are,
consequently, able to alter their form very considerably ; in such cases
special contractile elements are generally present.

The ectoplasm of Infusoria has generally the appearance of a thin,
sharply limited layer of protoplasm, which is distinguished from the rest
by its greater density and its higher refractive power; it is either homo-
geneous or has the special alveolar structure first described by Biitschli.
The name of pellicula is suggested in place of the ordinary term cuticula,
as this bounding lamella is not a dead secretory product, but merely a
metamorphosis-product of the protoplasm. Between the alveolar layer
and the endoplasm a specially differentiated layer can, in some cases, be
distinguished, and for this we may well use Biitschli’s name of cort'cal

* Proc. R. Soc. Edinb., xvi. (1888-9) pp. 131-5.
+ Mem. Acad. Imp. St. Pétersbourg, xxxvi. (1889) 36 pp. and 2 pls.
t Bibliotheca Zoolog., y. (1889) 78 pp. (7 pls.).

768 SUMMARY OF CURRENT RESEARCHES RELATING TO

protoplasm. This is either homogeneous or alveolar in structure; in
this layer trichocysts or trichocyst-like structures and pigments may be
deposited. The author gives detailed accounts of twenty-five forms,
among which are Glaucoma macrostoma sp.u., Urozona Biitschlii g. et
sp. n., and Balantiophorus minutus g. et sp. n.

Pigment of Euglena sanguinea.*—M. A. G. Carcin has studied the
colouring matter of this organism, regarded by Ehrenberg as a distinct
species, by Stein and Kent as a form of E. viridis, with which latter
view the author agrees. He gives its spectroscopic properties, and finds
it to be composed of extremely fine granulations, insoluble in water or
cold-alcohol, soluble in chloroform and concentrated nitrie acid, and
turning blue under the action of sulphuric acid. This substance, to
which the author gives the name rufin, is identical with Rostafinski’s
chlororufin, the colouring matter of Hzmatococcus, Chlamydomonas,
Trentepohlia, the antherids of Characez, and the oospheres of Bulbochete.
It is not, however, ideutical with Liebermann’s chrysoquinone, nor with
the colouring matter of the pigment-spot (eye-spot) of the lower alge,
which is not turned blue by sulphuric acid.

New Proteromonas.t—M. J. Kunstler gives a description of a new
Proteromonas which was found living commensally with the Green
Lizard in Gascony. The filiform body isabout 15 » long. The body is
more or less of an S-shape, and is at the same time twisted on itself.
The hinder extremity terminates in a fine point which may be of some
length. At the anterior end there is a single long flagellum the base of
which varies somewhat in character. This flagellum may be two to five
times the length of the body, is of some thickness, and often undulating
or spiral in shape. The author proposes to call it P. dolichomastia. It
is somewhat smaller than P. Regnardi.

Podophrya from Calcutta.t—Mr. W. J. Simmons gives a short
account of a species of Podophrya from Calcutta. The body is from
1/800 to 3/4000 in. in length, is about 1/1000 in. broad, and the stem
is about 1/1500 to 1/2000 in. in length. The form of the body appears
to vary somewhat. The colour is whitish, and in only one case were
the tentacles observed to present a knobbed appearance.

Structure of Rhizopod Shells.§s—Herr F. Dreyer, after explaining
the most important points in the structure of the shel!s of the Rhizopoda,
attempts to give some explanation of the phenomena. ‘The chief cause
of the form-types of the soft body and of the shell is to be sought for in
the mode of life of the Rhizopoda. Those that have shells belonging to
the perforate type and with pseudopodia radiating uniformly on all sides,
live free and rotating in the water. The monaxonic and amphitect
shells of the pylomatic type belong to Rhizopoda, which, in swimming
or creeping, maintain a definite perpendicular principal axis. The
eudipleural development owes its origin to creeping in a particular
direction. The specific evolution of the form-type once selected is
independent of the shell-material ; in the selection of this type, however,
the latter plays an important part, and this applies in a still higher

* Journ. de Bot. (Morot), iii. (1889) pp. 189-94 (2 figs.).
+ Comptes Rendus, cix. (1889) pp. 578-9.

t~ Amer. Mon. Mier. Journ., x. (1889) pp. 145-6.

§ Biol. Centralbl., ix. (1889) pp. 333-52.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 769

degree to the growth-type, for the structural material plays an
important part in determining the mode of growth of the Rhizopod
shell.

Some of the Thalamophora construct their shells of agglutinated
foreign bodies, partly of inorganic (sand, mud), and partly of organic
nature, while the greater part of the Thalamophoran shells are formed
by secretion of carbonate of lime; the skeletons of the Radiolaria
consist of silica. As the two first constituents are far less firm than
silica, there is a corresponding difference in the habit and mode of con-
struction of the two great primary groups of the Rhizopoda. Even a
slight examination shows that the shells of the Thalamophora are far
stouter and more massive than the Itadiolarian skeletons, which are
often exceedingly complicated, graceful, and elegant. The compara-
tively soft material which is employed by the former does not permit
them safely to erect such airy and complicated structures as the skeletons
of the latter, which are composed of solid, more or less elastic,
siliceous rods.

The distinctions, however, are still more profound, and affect the
whole structural plan of the shells and skeletons. In the Radiolaria
both growth-types appear widely distributed, but there is an unmis-
takable preponderance of the concentric growth, while in the
Thalamophora the terminal growth-type is exclusively represented.
The cause of this difference is to be found in the fact that these two
modes of construction make different demands upon the solidity of the
material; it is in the essence of the perforate-concentric mode of con-
struction that it requires to be carried out more lightly. As there is no
principal orifice the passage of the sarcode is by the pores of the shell,
which must not be too narrow, nor the intervening skeletal parts too
massive ; further, the union of the latticed spheres concentrically nested
one within the other is only possible by means of free radial rods,
which, again, must not exceed a certain thickness. The conditions of
the pylomatic-terminal mode of construction are, obviously, very
different.

The author quotes with approval the recent speculations of Neumayr,
as he proposes a phylogeny which agrees better with both the morpho-
logical and paleontological facts than is the case with the older systems.

In conclusion, attention is drawn to the interesting and significant
fact that Molluscan and Thalamophoran shells follow the same laws of
circumvolution. This form must have its cause, not in the nature of the
organisms, but in the circumstances of the external world, and is
dependent on statical and mechanical requirements.

Rhizopod-Fauna of Bay of Kiel.*—Dr. K. Mobius, who has already
described the Infusoria of the Bay of Kiel,f now gives an account of the
Rhizopoda; of the latter twenty-five species are now known, and as
sixty-three Infusoria have been described, it is clear that there are more
than eighty-eight Protozoa in this bay. In Actinolopus pedunculatus, as
F. E. Schulze observed, the nucleus is near the top of the more acute
pole of the oviform body. Vampyrella pallida sp. nu. is provided with
pseudopodia which have the power of moving from side to side in
pendulum-fashion ; it lives chiefly on the small diatom Navicula elliptica ;

* Phys. Abhandl. K. Akad. Wiss. Berlin, 1888 (1889) Abh. ii., 31 pp., 5 pls.

t¢ Ante, p. 234.

1889. 3H

770 SUMMARY OF CURRENT RESEARCHES RELATING TO

the species requires further investigation. A rather full account is
given of the incompletely known Dendrophrya radiata, first described by
Strethill Wright. Gromia gracilis is a new species with an oviform or
spherical, colourless test; the protoplasm is colourless, and the pseudo-
podial stalk has no roots. There aie a number of vacuoles, one con-
tractile vesicle, and:one nucleus. Reproduction is effected by transverse
and probably also by longitudinal division. Trichosphrocium sieboldi is
described at some length, and a special group is made for it, which is
called Trichosa, and thus defined:—Pseudopodia lobate; test flexible,
with pore-canals, but no large orifice and bilaminate; the outer layer
consists of special organic rodlets, the inner of a chitinous membrane.
The group vccupies a low position among the Testacea, and appears to
form a connecting link between the Perforata and the Amoebea. A
description is given of Biomyxa vagans, but it remains to be shown
whether it is an adult Rhizopod, or a developmental stage in the life
of a Protist. A new species of Amaba—A. prehensilis—is shortly
described.

Nuclearia delicatula.*—M. A. Astari finds that, in its vegetative
phase, Nuclearia delicatula is spherical, pyriform, oviform, and elongated,
but it is often irregular in form, and may be lobed. The protoplasm is
generally rich in vacuoles, and contains several nuclei. Needle-shaped,
simple, rarely branched, pseudopodia are given off from the body, which
is often surrounded by a mucous investment, the surface of which is
covered with granules.

The ground-mass of the body is formed by a homogeneous and
hyaline substance, the hyaloplasm ; in this, small granules are imbedded,
which together make up the granular plasma ; this latter is distributed
regularly through the body} as it generally reaches the periphery there
is no division of the body into an outer andaninner layer. The number
of food-vacuoles varies from four or five to so many that they give a
frothy appearance to the body, and they vary also considerably in size.
The author has failed to find contractile vacuoles.

Specimens may be quite colourless, or bright red, yellowish or
brownish; and the coloration of the body is dependent on the food.
‘The gelatinous investment is coloured reddish by Hanstein’s anilin-
violet, and can, as a rule, be seen only in free-living individuuls ;
Nucleariz which are put into the moist chamber lose their investment,
and become naked.

The process of ingestion of food is very interesting; when a short
filament of Oscillaria is seized, the organism ordinarily draws the alga
as a whole into the interior of its body; to effect this it approaches the
alga and touches it with its pseudopodia, and then gradually flows round
it; if the algar filament is too long, the Nuclearia either seizes part of it,
when the rest remains outside its body or breaks off, or it takes it ina
different way. It places itself at the end of the filament, and the
granular protoplasm begins to be depressed ; after a short time the cell-
membrane disappears at the point of junction, as though it had been
destroyed; the granular structures of the cell-contents alter their
position, and pass into the interior of the body of the Nuclearia. Later
on, the same fate happens to the second cell, then to the third, and so on,
In another case the author observed that a Nuclearia had attached itself

* Zool, Anzeig., xil. (13$9) pp. 408-16.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. ChE

closely to the end of a filament of Oscillaria, and flowed around two of
its cells ; after some time the contents of these two cells passed, in the
form of two granular layers, into the interior of the body of the Nuclearia ;
the remains of the cell-membrane were seen on the filament.

In all the cases observed, the Nuclearia attacked tle filament from
the end ; the cell-membrane was dissolved at the point of junction with
the hyaloplasm, and probably under the influence of some secretion of
that layer. ‘The undigested remains are got rid of in the form of balls
of various sizes and colours. In one case the hyaloplasm was seen to
send out outgrowths, in the interior of which small granules were
inclosed ; these outgrowths elongated, got narrower and narrower, and
were again drawn in, but the granules remained outside the body of the
Nuclearia.

Tn conclusion, the author deals with the phenomena of fusion and
division ; under certain, but not yet understood, conditions, Nucleariz
fuse with one another; it generally happens when several individuals
are collected together; the individuals that fuse are rarely of the same
size, one being generally larger than the other. Division is also to be
seen, but only in large individuals which are probably plasmodia formed
by repeated fusions.

Nuclearia is most closely allied to Vampyrella, but the systematic
position of these and some allied forms is still uncertain; Biitschli
places them with the Heliozoa; Zopf is doubtful as to the position of
Vampyrella ; the author thinks they should go with the Myxomycetes.

Reproduction of Foraminifera.*—M. ©. Schlumberger thinks that
Mr. Brady’s observations on Orbitolites complanata var. laciniata, which
formed the subject of a paper in this Society’s Transactions,t prove
without doubt that Orbitoliies is viviparous, and that the embryos are
formed in the chambers of the adult; to escape they have to injure the
parent, but this is of no account, as Orbitolites is easily able to repair its
“ plasmostracum.” As to the question of dimorphism, on which MM.
Schlumberger and Munier-Chalmas suggested two hypotheses, the
observations of Mr. Brady show that the one which explained the dimov-
phism by supposing that at a given moment the individual absorbs the
megalosphere, and replaces it by a new arrangement of more numerous
chambers, is the more correct.

Grassia ranarum.{—Dr. A. Schuberg brings forward evidence to
show that Grassia ranarum, with regard to whose position in the
systematic arrangement of the Ciliate Infusoria there has been some
difficulty, is not a definite organism at all. Similar appearances to it
may be obtained by scraping the mucous membrane of the frog. On this
Prof. B, Grassi § makes some remarks in the way of answer.

* Bull. Soc. Zool. France, xiii. (1888) pp. 222-4.
+ This Journal, 1888, p. 693.
¢ Biol. Centralbl., ix. (1889) pp. 284-7. § T. c., pp. 424-5,

Tl? SUMMARY OF CURRENT RESEARCHES RELATING TO

BOTANY.

A. GENERAL, including the Anatomy and Physiology
of the Phanerogamia.

a. Anatomy-*

(1) Cell-structure and Protoplasm.

Structure of the Cell.;—Dr. F. Noll gives a very useful résumé of
the more important researches during the last fifteen years on the
structure of the vegetable cell.

Nucleus in Dormant Seeds.{—From an examination of the cell-
nucleus in the seeds of a large number of species belonging to a great
variety of natural orders, M. O. W. Koeppen has come to the following
conclusions :—The best reagent for staining the nucleole is an aqueous
solution of methylen-blue, and this is also useful for the nucleus. A
nucleus is always present in the embryo cells, and almost always in the
cells of the seed which contain reserve-materials ; but is wanting in those
of the Typhacee and Phytolaceacee ; in the latter it becomes absorbed
before the ripening of the seed. In Monocotyledons and Dicotyledons
there is almost always only one nucleus in each endosperm-cell; in
Coniferee almost always more than one; in the embryo-cells almost
invariably only one. The absolute size of the nucleus varies very
greatly according to the species. Its form is usually regular in seeds
which contain no starch, very irregular in those whichdo. On germina-
tion the nuclei with irregular form sometimes assume a regular form,
sometimes remain unchanged. ‘The nucleus does not perish until after
the reserve-materials have passed out of the cell. A nucleole was
observed in most cells of the ripe seed which do not contain starch,
never in those which do. Its form is always spherical. The nucleus
never contains more than one nucleole.

Pollen of the Cycadex.§—M. L. Guignard states that the pollen of
the Cycadez has been studied of recent years by Juranyi and by Treub,
who carefully followed the development from the youngest stage, and by
Strasburger, who studied the membrane. Certain abnormal or ex-
ceptional facts described by Juranyi in relation to nuclear division
in the pollen-mother-cells appeared to want confirmation; and inci-
dentally the author’s attention has been directed to the structure of
the nucleus while ina state of repose. According to Juranyi the longi-
tudinal doubling of the primary segments in Ceratozamia longifolia
takes place immediately after their arrival at the poles, and not at the
stage of the nuclear plate. The author, however, has shown that the
doubling takes place at this latter stage. The question as to whether
the nucleus in a state of repose incloses a single chromatic filament is
then discussed ; and the paper concludes by describing in detail the
successive stages of structure of the nucleus in a state of repose, and the
different stages of division as occurring in Ceratozamia mewicana.

* This subdivision contains (1) Cell-structure and Protoplasm; (2) Other Cell-
conteuts (including Secretions); (8) Structure of Tissues; and (4) Structure of
Organs. t+ Flora, Ixxii. (1889) pp. 155-68.

{ ‘Ueb. d. Verhalten d. Zellkernes im ruhenden Samen,’ Jena, 1887, 50 pp. See
Bot. Centralbl., xxxix. (1889) p. 86.

§ Journ. de Bot. (Morot), iii. (1889) pp. 222-6, 229-36 (1 pl.), and Bull. Soe. Bot.
France, xxxvi. (1889) pp. 206-11.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 773

(2) Other Cell-contents (including Secretions).

Composition of Chlorophyll.*—Prof. G. Arcangeli has repeated
_Kraus’s experiments on chlorophyll with benzol, substituting for the
benzol petroleum benzine (benzina di petrolio), and has obtained similar
results. He concludes that chlorophyll is not a simple compound of two
substances, pure chlorophyll and xanthophyll, but rather of a series
of green and a series of yellow pigments.

Composition of Tannin.j—Commenting on Kraus’s paper} on the
physiology of tanniu, Herr F. Reinitzer states that under the name of
tannin a variety of substances are known in vegetable physiology, which
by no means exhibit similar chemical reactions. Thus the tannin of
oak-apples consists of a mixture of digallic acid and a glucoside of
digallic acid. He suggests that the terms “ tannins” and “ tannic acids ”
should be banished from vegetable physiology and vegetable chemistry.

Sphero-crystals.§—M. E. Rodier states that in Senecio vulgaris
sphero-crystals are produced in ali the tissues of the stem, but princi-
pally in the cortical and medullary parenchyme. They are more
regularly spherical than those of inulin, but are arranged in nearly the
same manner in the cells. The colour of these bodies is a more or less
deep yellow. Anilin colours do not affect spherocrystals; but they
are easily soluble in cold, and still more readily in hot water. When
treated with ammonium oxalate, they are destroyed and replaced by
crystals of calcium oxalate, thus showing that spherocrystals contain
lime. By the application of various reagents it may be seen that sphero-
crystals are composed of a nucleus and an amorphous envelope, probably
of organic nature, separated by a crystalline cortex containing lime.

Mucilage in the Endosperm of Leguminose. ||—Herr H. Nadelmann
states that the mucilage which is frequently found in the cells of the
endosperm of Leguminose, together with starch, aleurone, and a fatty
oil, serves in the first place as a reserve food-material, the secondary
thickenings of the cell-wall which are composed of cellulose being
absorbed and consumed in the process of germination. They are pro-
duced directly in the form of mucilage, and not as the result of a
modification of cellulose. The secondary thickenings, which often occur
also in the cells of the cotyledons, are, on the other hand, never com-
posed of mucilage.

Starch in the Epiderm.{[—Prof. R. Pirotta finds, in several species
of Rhamnus, considerable quantities of starch in the epidermal cells,
where it remains during the dead season, to be used up again on the
resumption of vegetative activity. The epiderm appears, therefore, to
act, in these cases, as a reservoir of starch for purposes of nutrition.

Gluten in the Grain of Corn.**—According to Herr W. Johannsen,
gluten forms the main portion of the protoplasm in the amylaceous endo-
sperm-cells of wheat, and is not the result of the action of a ferment.

* Malpighia, iii. (1889) pp. 3-14.
+ Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 187-96.
t Cf. this Journal, ante, p. 654. | § Comptes Rendus, eviii. (188) pp. 906-9.
|| Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 248-55.
{ Malpighia, iii. (1889) pp. 61-6.
** Résumé du compte-rendu d. travaux d. laboratoire d. Carlsberg, ii. (1888)
pp. 199-208 (2 figs.). See Bot. Centralbl., xxxix. (1889) p. 22.

TT4 SUMMARY OF CURRENT RESEARCHES RELATING TO

The so-called “gluten-layer” beneath the pericarp contains neither
gluten nor any ferment, but small grains of a nitrogenous substance
imbedded in fatty protoplasm, as well as diastase.

Formation of Calcium oxalate in Plants.*—Dr. C. Acqua discusses
the mode and place of formation of the crystals of calcium oxalate in
plants. He decides against the hypothesis that it may be formed in
all the turgid cells of the parenchyme, from whence it is carried in the
cell-sap to those where it is ultimately deposited in the crystalline form.
He believes, on the contrary, that the calcium oxalate, though not the
oxalic acid, is formed in the crystalliferous cells. The acid may be
formed in all the turgid cells of the cortical and medullary parenchyme,
where it combines with potassium, and circulates chiefly through the
intercellular spaces. It is there prevented from combining with the
calcium-salts in the cell-sap by the coating of ectoplasm ; while the cell-
walls of the crystalliferous cells possess the property of accumulating in
them calcium-salts, which then decompose the potassium oxalate, and
cause the deposition of crystals of calcium oxalate. This hypothesis is
confirmed especially by observations on Mesembryanthemum acinaciforme
and Euonymus japonicus.

Prof. A. Poli} replies to strictures made by Dr. Acqua on his previous
writings on this subject.

Calcium oxalate in Plants.t—In opposition to the statement of
Schimper, Dr. C. Wehmer finds that in Symphoricarpus, Alnus, and
Cratzgus, there is no transference of the calcium oxalate from the leaves
to the leaf-stalk, branch, or stem, nor from the mesophyll to the vascular
bundles ; but that, on the other hand, the oldest leaves always contain the
largest amount of this salt.

In Cratzgus the buds are found to be filled with calcium oxalate in
the autumn ; and this is not deposited with the first growth in spring ; but
only at a later period of the formation of the new organs.

The absence of calcium oxalate in certain parasites (Rafflesia, Lathreza,
Cuscuta, Cassytha) he attributes to the suppression of the production of
plastic substances from distant organs.

In reply, Dr. F. G. Kohl § points out that the explanation is hardly
satisfactory, since we have to do with the absence, not of oxalic acid, but
only of calcium oxalate; and that Lathrea squamaria does at certain
times contain large quantities of starch. He also dissents from
Wehmer’s conclusions as to the distribution of calcium oxalate in
Symphoricarpus, &c.

Perfume of the Rose.||M. R. Blondel states that the odour of
the rose is found to be principally developed in the group Centifolia,
and particularly in R. centifolia. The Canina group possesses an
analogous odour, which is, however, generally much more feeble.
The hybrids produced by crossing Tea Roses (RB. fragrans) and Ben-
galese Roses (R. semperflorens) with RR. centifolia give a great
variety of odours; while the Noisette Roses (hybrids of R. moschata

* Malpighia, iii. (1889) pp. 17-48, 160-6 (1 pl. and 1 fig.). Cf. this Journal, ante,
p. 655. + T. ¢., pp. 173-5.
+ Bot. Ztg., xlvii. (1889) pp. 141-55, 169-78; Bot. Centralbl., xxxviii. (1889)
pp. 648-9 ; and Ber. Deutsch. Bot. Gesell., vil. (1889) pp. 216-33 (1 pl.).

§ Bot. Centralbl., xxxviii. (1889) pp. 649-52.

|| Bull. Soe. Bot. France, xxxvi. (1889) pp. 107-18,

ZOOLOGY AND BOTANY, MICROSCOPY, ETC, Tho

and R. semperflorens) are generally scentless. In the Banksia group,
R. Banksia alba possesses a very pronounced odour of violets, while
R. Banksia lutea has no marked odour. The Cinnamomex, with one or
two exceptions, do not possess a strong odour, and the Pimpinellifoliz are
likewise almost scentless. In the Villosz the flowers are nearly scent-
less, but the leaves are glandular, and omit an odour of tercbinthin
(RB. villosa). The section Rubiginose are also remarkable only on
account of the peculiar perfume emitted by the leaves of several species.
The author then describes in detail the tissues inclosing the fragrant
principle. In the petals the essential oil resides in the cells of the two
layers of the epiderm; its presence may be easily detected by using
osmic acid.

Odour of the Glands in Rosa.*—M. F. Crépin calls attention to the
interest connected with the substances contained in the glands of different
species of Rosa, which deserve closer observation than they have at pre-
sent received, He points out that the odour of the substance contained
in the glands of the sweet-briar (R. rubiginosa) and of the species nearly
allied to it which make up the section Rubigine, is totally different from
that of all other species of the genus.

(8) Structure of Tissues.

Laticiferous Tubes.t—Mr. P. Groom has investigated the distribu-
tion of laticiferous tubes, with reference to their function, in several
species of Huphorbiaceew, Papayaces, Artocarper, Asclepiadesw, and
Composite. He finds that the tubes may be distributed throughout the
whole of the leaf, and may end in contact both with the epiderm and the
mesophyll. In some leaves the endings of the tubes are chiefly in con-
tact with the epiderm; in others chiefly or exclusively away from it.
In the leaves the tubes may leave the assimilating tissue altogether, as
they do in the Artocarpez, when they pass through the aquiferous tissue
to the epiderm. There is, therefore, no essential connection between
the endings of the laticiferous tubes and any particular tissue of the
leaf. From these facts the author draws the conclusion that no conduc-
tion of carbohydrates takes place through the laticiferous tubes, as has
been supposed by some, this process being effected, in the leaves, mainly
through the parenchyme of the veins.

Vesicular Vessels of the Onion.{—Mr. A. B. Rendle finds that the
structures which go by this name are not correctly so-called, being
enlarged cells in which no cell-fusion has taken place. He proposes
that they should be termed in future laticiferous cells. Their resem-
blance to sieve-tubes is simply structural; in the great majority of
instances the pits in their walls are not perforated. With regard to
their function, they contain no ordinary food-material, and have no
connection either with the assimilating parenchyme or the vascular
bundles. Their contents is a more or less granular turbid fluid of the
nature of latex, and must probably be regarded simply as an excretory
product.

Intercellular Spaces in the Tegument of the Seed of Papilionacez.§
—Dr. O. Mattirolo and Sig. L. Buscalioni find in the tegument of the

* CR. Soc. R. Bot. Belgique, 1889, pp. 64-7.
+ Ann. of Bot., ili. (1889) pp. 157--68 (1 pl.). ¢ T.c., pp. 169-77 (1 pl.).
§ Malpighia, iii. (1889) pp. 143-59 (1 pL). ;

HUG SUMMARY OF CURRENT RESEARCHES RELATING TO

.seed of many species of Papilionacese a structure hitherto known only
among Ferns; for the wall of the intercellular spaces is clothed with a
number of filiform processes. These processes are most common in
the neighbourhood of the micropyle and hilum, and, when most fully
developed, take the form of capitate rods, or sometimes of elongated
filaments. The mierochemical reactions of these substances are given
in detail; and the authors conclude from them that these rods are identical
in nature with those of the Marattiaces, and are formed of a substance
different from cellulose; or rather, of two different substances, one of
which composes the mass of the process, the other its investing mem-
brane; neither are they composed of protoplasm. The substance of
these processes, like the secretion of glands, is deposited in the cell-
wall and investing membrane, which latter is continuous with the
investing membrane of the intercellular space.

Strengthening Apparatus in the Stem of Saxifragaceze.*—M. Thou-
venin describes the variations in the structure of the stereome to be
found in the underground stems of Saxifragaceze, which he groups under
eight heads, dependent on the degree of development of the pith, cortex,
and medullary rays, and on the structure of the pericyele and endoderm.

Radial Union of Vessels and Wood-parenchyme.j—Herr F.
Gnentsch describes several different ways in which the vessels of two
successive annual rings unite, as well as differences in the distribution
of the vessels. He draws the general conclusion that the annual ring is
not so completely closed as is usually supposed. On the contrary, the
vessels, one of the most important constituents of the xylem, regularly
unite at the boundary of two successive rings, either directly or by
tracheides. Through this union a regular interchange of formative
material takes place, especially in the spring, when the medullary rays
are unable to perform this function to any large extent. 'The wood-
parenchyme-cells, on the other hand, are in general concerned only with
tangential and not with radial conduction.

Formation of healing Periderm.t—Herr L. Kny has investigated
the influence of light, temperature, moisture, pressure, and other external
agencies on the formation of periderm which follows the infliction of
injuries on the tubers of many plants. He finds that the cell-divisions
which inaugurate the formation of the periderm take place indifferently
in diffused daylight and when light is excluded; and that the later
processes and the suberization in the periderm-cells are not materially
influenced by the amount of light. These cell-divisions are promoted
by a medium moisture of the air. The position of the cut surface,
whether facing upwards or downwards, or whether vertical or horizontal,
does not affect the cell-division. The free oxygen of the air is essential,
both for the commencement of the cell-division and for the formation of
cork.

Formation and Development of Libriform Fibres.§—Herr A. Wieler
has investigated the phenomena connected with the development of the
libriform fibres in the xylem of the stem of dicotyledonous plants,

* Bull. Soc. Bot. France, xxxvi. (1889) pp. 125-33.

+ ‘Ueb. radiale Verbindungen d. Gefasse u. d. Holz-parenchyms u.s.w.,’ Regens-
burg, 1888. See Bot. Centralbl., xxxix. (1889) p. 34.

} Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 154-68.

§ Bot. Ztg., xlvii. (1889) pp. 517-28, 533-40, 549-61 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. rgd

especially Urtica dioica, Robinia pseudacacia, Quercus sessiliflora, and
Phaseolus multiflorus, and finds the development of this tissue greatly
dependent on external conditions. These conditions determine the
proportion in which the various tissues or kinds of cells are developed
from. the initial cambium-cells; but the extent of this variability is
limited for each species. The formation of the libriform fibres, or of
the fibre-cells which replace them, appears to be in all cases a
mechanical one.

Secondary Medullary Rays.*—Herr HE. Schmidt has investigated
the mode of formation of the secondary medullary rays, especially in
Pinus sylvestris. They originate in the cambium, but not from any
sudden change; rather as the final result of a series of changes
eradually leading up to them.

Foliar Medullary Bundles of Ficus.|— Conte Dr. L. Macartili finds
no trace of medullary bundles in the stem of any species of Ficus ex-
amined; on the other hand, they are numerous in the leaf-stalk and
veins of the leaf. They always originate from the node, and are
portions of leptome which separate, for a longer or shorter distance,
from the leptome of the normal bundles, towards which they then turn,
to be reunited with them.

(4) Structure of Organs.

Ovuliferous Scales of Coniferee.t—Prof. F. Delpino discusses the
morphological value of the ovuliferous scales of the Abietinez and other
Conifere. He states that in the Pteridophyta, Gymnosperms, and
Angiosperms the evolution of the carpid or fertile leaf is manifestly
homologous, with slight differences. The carpid or fertile leaf must be
regarded as a phyllome ideally divisible into three, and frequently
actually tripartite, with the median division sterile, and the two lateral
divisions fertile and ovuliferous or sporangiferous. If the phyllome
remains entire we have the pleurosporangium of many ferns, or pleuro-
spermy, which is normal in the Cycadez and in nearly all Angiosperms.
But frequently in the fertile leaf the sporangiferous divisions separate
from the median sterile plane of division into a bundle opposed and
superposed to the median division, as occurs in Aneimia. It may then
happen that, from the first, all the fertile divisions coalesce into a single
fertile body opposed and superposed to the sterile division ; and to this
phenomenon the author applies the term antixporangism in Pteridophyta,
antispermy in Phanerogams.

Antisporangism occurs in at least two sections of the Pteridophyta,
and independently of one another—in the Marattiaceze and the Ophio-
glossacee. The axillary sporangism of the Lycopodiacez is also a case
of antisporangism reduced to its simplest form, with the production of
three sporanges in Psilotum, two in T'mesipteris, and only one in Lyco-
podium, Selaginella, and Phylloglossum. ‘he axillary sporangism of the
fsoetez is derived directly from the antisporangism of Ophioglossum.

The antispermism of the Gymnosperms is manifested in Salisburia,
in the archaic Sciadopitys, and in the Abietine, Cupressinee, Arau-
carieze, and Podocarpez, but with a singular difference of development
in the median and the two fertile portions of the carpid. In the

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 143-51 (1 pl.).
+ Malpighia, ili. (1889) pp. 129-33. { T.¢., pp. 97-100.

778 SUMMARY OF CURRENT RESEARCHES RELATING TO

Abietinez, Cupressinex, and Sciadopitys the median region of the carpid
(bract of authors) is very small, while the two placente are thick and
large, and are fused into one body. In the Podocarpee, on the other
hand, and especially in Araucaria, the median region is well developed,
the fertile body small and more or less connate with the median region.
The barren leaf of Ophioglossum stands in precisely the same relation to
its fertile leaf as the barren leaf or median barren portion of the carpid
of Salisburia to its fertile portion.

Although pleurospermy is far the most prevalent phenomenon in
Angiosperms, yet there are instances of antispermy, as in the true
central placentation of the Primulacee and Plumbaginex. Here there
are five tripartite carpids. The five median portions coalesce and form
the unilocular ovary with its single style or five styles; the ten lateral
ovuliferous portions combine into a large central placentary body,
resulting evidently from the fusion of five antispermic bodies. Anti-
spermy occurs also in the Juglandez, Loranthacee, and Santalacez.

Sensitive Stamens in Composite.*—Prof. B. D. Halsted records
the occurrence of sensitive or elastic stamens in the following species of
Composite :—Echinacea angustifolia, Heliopsis levis, Lepachys pinnata,
and Rudbeckia hirta. The movements appear to be in all cases con-
nected with the distribution of the pollen.

Bracteoles of the Involucre in the Cynarocephale.j—M. L. Daniel
describes the variations in the nature of the foliar parenchyme in this
section of Composite. The absence of stomates in the parts of the bract
placed in obscurity is a consequence of the sclerification of the epiderm,
and not of the obscurity. The structure of the parenchyme depends
on the influence of the surroundings in which the bract or bracteole is
placed.

Secund Inflorescence.{—Tracing the development of various instances
of this mode of inflorescence (excluding the scorpioid), Mr. T. Meehan
finds that it is common in perennial, but not in annual plants. He
believes it to be a comparatively recent stage in evolution, in which a
geotropic stem has assumed an erect condition, and arises from the
alternate twisting of the pedicels in contrary directions.

Ovaries and Achenes of the Rose.s—M. F. Crepin states that in
the sections of Rose known as Carolinw, the ovules, and later the
achenes, will be found situated at the bottom of the receptacle, while in
Cinnamomez the ovaries or their achenes will be found situated not only at
the bottom, but also to a certain height on the lateral walls. This affords
a character for separating the section Caroline from the Cinnamomez.

Achenes of Coreopsis.||—-Mr. J. N. Rose describes the various forms
of achene (cypsela) to be found in Coreopsis, one of the Composite. They
may be flat or somewhat four-sided, straight or curved, orbicular to
linear-oblong in outline, glabrous to pubescent, winged or wingless,
with entire or laciniate toothed margin, the apex truncate or emarginate,
the pappus of two awns or of teeth or scales, these generally hispid on

* Bot. Gazette, xiv. (1889) pp. 151-2. Cf. this Journal, ante, p. 544.

+ Bull. Soc. Bot. France, xxxvi. (1889) pp. 133-43. Cf. this Journal, ante,
p- 408. { Proc. Acad. Nat. Sci. Philad., 1889, pp. 53-6 (2 figs).

§ OR. Soc. Bot. Belgique, 1889, pp. 87-8.

|| Bot. Gazette, xiv, (1889) pp. 145-51 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 779

the upper part; or all these are wanting. A list of the species of
Coreopsis is given, with descriptions founded on characters drawn from
the achenes.

Floating-organs. *—After a discussion of the mathematical problems
connected with contrivances for hindering the descent to the ground of
parts of plants, Herr H. Dingler classifies the various kinds of floating
organs under twelve distinct heads, viz.:—(1) Dust-like (Schizomycetes,
spores of Fungi, Vascular Cryptogams, &c., the pollen-grains of anemo-
philous plants); (2) Grain-like (seeds of Papaveracew, Orobanchacee,
&c.); (3) Furnished with bladders (fruit of Valerianella, seeds of
Orchidew, achenes of Cynara Scolymus, &c).: (4) Hair-like (many Bro-
meliacez) ; (5) Disc-like and flat (fruit of elm, seeds of some Iridew
and Liliacee); (6) Disc-like and convex (fruit of Paliurus aculeatus ;
seed of Hecremocarpus scaber ; (7) Parachute-like (achenes of Dipsa-
caceew, Plumbaginew, and many Composite; (8) Cylindrical and
winged (fruit of many Polygonacew and of Halesia) ; (9 and 10) With
ridges which give a sail-like form (Ailanthus and some Bignoniacew
and Ternstrcemiacee); (11 and 12) Samaras and other fruits and seeds
which fall with a helicoid motion (samara of ash, maple, &c., fruit of
Liriodendron tulipifera, seeds of many Coniferz).

Pitcher of Nepenthes.j—From a study of the development of the
leaf of several species of Nepenthes, Prof. F. O. Bower has come to the
conclusion that the leaf is not a simple but a branched one, the space at
the back of the lid being its organic apex; the whole leaf consists
of :—(1) a phyllopode, winged throughout its whole length, terminating
in the spur, and developing the pitcher itself as an involution of its
upper surface; and (2) a pair of pinne. which show congenital coales-
cence across the frontal face of the phyllopode, and constitute the lid of
the pitcher. By phyllopode he understands the main axis of the leaf
(including petiole), exclusive of all its branches.

Pitchered Insectivorous Plants.{—From observations on species of
Nepenthes, Heliamphora, Sarracenia, Darlingtonia, and Cephalotus, Dr.
J. M. Macfarlane has also come to the conclusion that in the first four
genera the leaf is compound, and consists of from two to five pairs of
leaflets, exhibiting a marked tendency to dorsal fusion of the leaflets
from apex to base. This is demonstrated by comparison of the seedling
with the adult leaves. The pitcher is, in these genera, a deep dorsal
involution of the mid-rib just above the termination of the fused under
pair of leaflets. The lid itself is made up of two leaflets produced on
either side of the median mid-rib, which may afterwards be excurrent,
or the leaflets may fuse distally to form a median dorsal process. Tho
pitchers of Cephalotus appear to differ in every respect from those of the
other genera, and probably represent one of a chain of forms otherwise
lost.

Homology of Stipules.s—Studying the development of the parts of
the flower in Magnolia and many other plants, Mr. T. Meehan assigns

* «Die Bewegung. d. pflanzlichen Flugorgane, Miinchen, 1889, 342 pp. and
8 pls. See Flora, lxxii. (1889) pp. 169-79.

+ Ann. of Bot., iii. (1889) pp. 239-52 (1 pl.).

} T.c., pp. 253-66 (1 pl.). Cf. this Journal, ante, p. 408,

§ Proc, Acad. Nat. Sci. Philad., 1889, pp. 62-4.

780 SUMMARY OF CURRENT RESEARCHES RELATING TO

reasons for regarding the petals and sepals, not as modified entire leaves,
but as modifications of the base of the petiole or stipule, the main
purpose of both organs being the protection of the tender parts of the
flower. It is not uncommon in the rose for the ordinarily suppressed
lamina of the leaf to reappear, in cultivation, at the apex of the sepals.

Stem and Leaf of Utricularia.*—According to Prof. K. Goebel
several exotic species of Utricularia exhibit a remarkable absence of
differentiation between axial and appendicular organs. We have here
leaves which have the power of developing into organs, the stolons, which
have all the characters of a shoot; while, on the other hand, in some
species, large cylindrical bladdcr-bearing stolons become flattened off at
their apices into leaves.

Opening and Closing of Stomates.j—Prof. 8. H. Vines assigns
reasons for his conclusion, derived from observation of the phenomena
connected with the opening and closing of stomates, that the openixg is
not due to stimulation by light or any other agent of the irritable
protoplasm of the guard-cells, but is a purely passive one, depending on
the formation of osmotically active organic substances in the chloro-
phyllaceous guard-cells when exposed to light; while, on the other
hand, their closing is an active process determined by the stimulating
influence of a certain relation between loss and supply of water on the
irritable protoplasm of the guard-cells.

Colleters and Glands of Gunnera.t—Herr P. Merker describes the
colleters on the leaves of various species of Gunnera as being formed —
originally of three epidermal cells, other parenchymatous cells immedi-
ately beneath the epiderm subsequently taking part in their formation,
and forming their foot. The mucilage in the glands of the stem is
the seat of the peculiar colonies of Nostoc so often found in several -
species. The author does not regard these as carrying on a symbiotic
existence, but rather as parasitic, and inflicting injury on the host.

Abnormal Formation of Rhizome.s—Herr H. Vochting describes
the production of rhizomes on aerial stems of Stachys tuberifera and
S. palustris. These resembled the normal rhizomes in all essential
particulars, differing chiefly in the greater length of the imternodes, in
the scales being replaced by leaves, and in the presence of chlorophyll.
They serve to show the close morphological connection between under-
ground and aerial stems.

Aerating Roots.|—Prof. W. P. Wilson describes the mode of growth
in the excrescences known as “ knees” which characterize the American
cypress, Taxodium distichum, when growing in swamps. He finds that
they are undoubtedly for the purpose of aerating the plant; and that it
is quite possible to produce similar aerating organs in other plants by
crowing them in very swampy localities. “

* Flora, Ixxii. (1889) pp. 291-7 (1 pl.). Cf. this Journal, ante, p. 545.

+ Ann. of Bot., iii. (1889) pp. 271-4. { Flora, lxxii. (1889) pp. 211-32 © pls.).
§ Bot. Ztg., xlvii. (1889) pp. 501-7 (1 pl.).

|| Proc. Acad. Nat. Sci. Philad., 1889, pp. 67-9.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 781

B. Physiology.*
(1) Reproduction and Germination.

Flowers and Insects.|—Mr. C. Robertson describes the mode of
fertilization and the insect visitors in the following American plants :+-—
Delphinium tricorne, Nuphar advena, Nymphza tuberosa, N. odorata,
Dicentra Cucullaria, Viola pubescens, V. palmata var. cucullata, V. str iata,
V. pedata var. bicolor, V. lanceolata, Claytonia virginica. The inversion
of the flower of most species of Viola appears to be particularly favourable
to bees of the genus Osmia, the flowers of V. pubescens, palmata, and
striata being specially adapted to them. The bearded violets are
sternotribe, while V. pedata, which is mainly visited by long-tongued
bees, has become nototribe.

Dimorphism of Polygonum.{—Mr. T. Mechan finds several American
species of Polygonum (inciuding the European P. Persicaria, aviculare,
and Hydropiper) to b: dimorphic, with larger and smaller flowers. The
smaller flowers are perfectly formed, and are abundantly nectariferous
and polliniferous, and apparently constructed for self-fertilization, but
never produce seed. The larger flowers are apparently adapted for cross-
fertilization, and are abundantly fertile, but are never visited by insects.
They are, in fact, fertilized in the bud, and are frequently cleistogamous.

Properties of Hybrids.§—Dr. F. Hildebrand gives details of a long
series of experiments on hybridization, chiefly between different species
of Cistus, Abutilon, Chameedorea, and Owalis. In the case of Chameedorea,
a genus of palms, he finds the hybrids to be perfectly fertile with one
another, although the original parents belonged to sharply differentiated
species. In Ovxalis the hybrid presented a mingling of the character of
the parents in an immense varicty of ways. The hybrids generally
exhibited a more luxuriant growth than the pure forms, and blossomed
earlier.

(2) Nutrition and Growth (including Movements of Fluids).

Influence of “‘ Ringing” on Growth.||\—According to Herr T. Miiller,
“ringing” of branches produces a more active growth above, a less
active growth below the ring; this is chiefly displayed in the wood, less
in the secondary cortex and periderm. Starch is usually entirely absent
from the portion below the ring, and tannin is more abundant above
than below, while the reverse is the case with calcium oxalate.

Obtaining of Nitrogen by Graminee and Leguminose.§—Herren
H. Hellriegel and H, Willfarth maintain, as the result of a long series of
experiments, an essential difference in the mode in which G Graminex and
Leguminose obtain their nitrogen. The growth of barley and oats is in
direct proportion to the amount of nitrates contained in the soil, and they

* This subdivision contains (1) Reproduction and Germination; (2) Nutrition
and Growth (including Movements of Fluids); (8) Irritability ; and (4) Chemical
Changes (including Respiration and Fermentation).

iT ‘Bot. Gazette, xiv. (1889) pp. 120-6, 172-8 (4 figs.).

t Proc. Acad. Nat. Sci. Philad., 1889, pp. 59-61.

§ Jenaisch. Zeitschr. Naturw., xxiii. (1889) pp. 413-548 (2 pls.).

|| ‘Ueb. d. Hinfluss d. Ringelschnittes auf d. Dickenwachsthum u. d. Stoffver-
theilung,’ Halle, 1888, 53 pp. See Bot. Centralbl., xxxix. (1889) p. 31.

4] ‘ Unters. iib. d. Stickstoffnahrung d. Gramineen u. Leguminosen,’ Berlin, 1+88,
234 pp. and 6 pls. See Bot. Centralbl., xxxix. (1889) p. 138; and. Ber. Deutsch.
Bot. Gesell., vii. (1889) pp. 138-43.

782 SUMMARY OF CURRENT RESEARCHES RELATING TO

appear to have no other source of nitrogen; while, on the other hand,
this is not the case with vetches, which may grow luxuriantly in a soil
containing no nitrogen. They must, therefore, obtain this element from
some other source, which appears to be the free nitrogen of the atmo-
sphere. They are not, however, able to obtain it directly from the air ;
this is effected by microbes, which carry on a symbiotic existence with
several species of Leguminose, usually stored up in special tubercles on
the root; they are not able to make use, for this purpose, of the microbes
contained in the soil.

Power of plants to absorb Nitrogen from the air.*—Herr B. Frank
replies to the statements of Hellriegel and Willfarth, and maintains his
previous assertion,{ that all plants possess the power, under certain
circumstances, of assimilating directly the free nitrogen of the air. The
contrary results obtained by Hellriegel and Willfarth in the case of
plants belonging to any other order than the Leguminose, he attributes
to the plants being in a weak or unhealthy condition, in which state
they are entirely dependent for their nutrition on previously formed
organic nitrogenous compounds. He points out that there is no single
direct observation to connect the “bacteroids” in the root-tubers of
Leguminose with this supposed function, that the fact of their being
living organisms is subject to very considerable doubt, and that their
structure and mode of life are altogether different from those of
““mycorhiza,’ in which a symbiosis between the fungus and the
enveloped root has been satisfactorily demonstrated.

Movements of Gases in Plants.t—Herr P. Kruticki finds the per-
meability of different plants for air to vary exceedingly, and to bear no
relationship to their permeability for water. In winter the air contained
in the branches contains less oxygen and more nitrogen, and a con-
siderably larger proportion of carbon dioxide than atmospheric air. At
the beginning of spring the proportion of oxygen increases, while that
of carbon dioxide decreases ; until, when the buds begin to open, the
composition of the contained air is nearly that of the surrounding
atmosphere. This indicates a decrease in the activity of the physio-
logical processes within the plant in the winter.

Curvature of Growing Organs.$—-Pursuing his investigations on
this subject, and replying to the observations of Noll,|| Herr J. Wortmann
sums up the main results as follows :—The three variables which deter-
mine the growth of a cell are turgor, extensibility of the cell-wall, and
the presence or access of water; every alteration in any one of these
forces brings about a change in the growth. As long as a cell grows,
the production of osmotic substances in the cell-sap and of elements of
the cell-wall, and absorption of water must continue. The increased
extensibility of the cell-wall of the under-side of a cell which is curving
upwards (epinastic) is the result of a diminished formation of cell-wall,
while the diminished extensibility of the cell-wall of the upper side is
the result of an increased formation of cell-wall.

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 234-47.

+ Cf. this Journal, ante, p. 550.

{ Script. Bot. Horti Univ. Imp. Petropolitane, ii. (1888) pp. 115-53. See Bot.
Centralbl., xxxix. (1889) p. 30.

§ Bot. Ztg., xlvii. (1889) pp. 453-61, 469-80, 485-92. Cf. this Journal, ante,
p. 92. || Cf. this Journal, ante, p. 413.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 783

(4) Chemical Changes (including Respiration and Fermentation).

Influence of Oxygen in the Decomposition of Albuminoids.*—
Prof. W. Palladin maintains the view that the carbohydrates, especially
starch and cellulose, result from the decomposition of the proteids ;
the amides, especially asparagin, being secondary products. This is
the cause of the accumulation of asparagin during germination,
which is again converted into proteid when the newly-formed carbo-
hydrates are assimilated. ‘The author dissents entirely from the theory
of Pfetfer that the nitrogenous substances are translated through the
plant in the form cf asparagin. ‘I'he breaking up of proteids into
asparagin and carbohydrates must be accompanied by a considerable

consumption of oxygen, which is actually the case. In the respiration,
a

especially of germinating seeds, the proportion O - is considerably less

than unity. The carbohydrates must therefore be regarded as products
of oxidation of the albuminoids.

Formation of Starch out of Sugar.;—Herr W. Saposchnikoff has
determined the direct production of starch out of cane-sugar in the
leaves of many plants, and not as the result of the metastasis of other
substances already present in the leaf.

Alcoholic Fermentation of Milk.t—It had been shown by Duclaux
and Adametz, that the alcoholic fermentation of milk can be effected
without inducing coagulation by means of certain yeasts. It was after-
wards found that milk fermented with the yeast described by Duclaux
coagulated on boiling. M. Martinaud now states that under certain con-
ditions the two phenomena, the alcoholic fermentation of the sugar and
the coagulation of the milk, can be brought about with any kind of yeast.
If a 10 per cent. solution of glucose or maltose, added to milk in
quantities varying from 10 to 8U per cent., be sown with the Duclaux
ferment, or with any one of the following species of Saccharomyces,
cerevisiz, ellipsoideus, pastorianus, or apiculatus, the milk coagulates in
from 17 to 116 hours. The same phenomenon is observed if saccharose
be used, except with S. apiculatus.

The conditions which retarded or fayoured this coagulation were
examined by varying the quantities of water and of sugar, separately and
together, and also by adding more sugar than milk naturally contains.
In this way it was shown that when fermentable sugar is present in
large quantities, the milk coagulates more rapidly with an increasing
dilution.

- With regard to the process of coagulation, it was found that when
pure milk passed through a Chamberland filter is fermented, before an
appreciable quantity of alcohol is formed, the liquid became cloudy from
the appearance of a fine precipitate. This coagulation does not take place
suddenly when unfiltered milk is used, but a deposit of casein which goes
on increasing until the end of fermentation.

A similar condition of things is observed if the casein which has

* «Der Einfluss d. Sauerstoffs auf d. Zerfall d. Eiweissstoffe in d. Pflanzen’
(Russian), Warsaw, 8vo, 1889, 93 pp. See Bot. Centralbl., xxxix. (1889) p. 23;
also Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 126-30.

+ Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 258-60.

¢ Comptes Rendus, eviii. (1889) pp. 1067-9. Cf. this Journal, ante, p. 426.

784 SUMMARY OF CURRENT RESEARCHES RELATING TO

been precipitated be redissolved in a saccharated solution passed through
a Chamberland filter and fermented. Hence the action of the yeast
upon the soluble casein, the casein in suspension, and the precipitated
and redissolved casein, is the same.

y. General.

Development of Annual Plants.*—In a further paper on this sub-
ject M. H. Jumelle states that when plants are grown in a medium
deprived of salts, the absence of the salts not only causes a natural
diminution of dry substance which is directly due to this absence, but
the proportion of water in relation to the dry weight of the plant is also
diminished. This results in certain anatomical and morphological modi-
fications, which always accompany the diminution of the quantity of
water ina plant. The large proportion of water in plants rich in salts
is due to the slowness of the transpiration, and especially to the augmen-
tation of the absorption. When a plant is provided with salts, but is
grown in complete darkness, the absorption of mineral substances is
excessively feeble, and takes place especially at the commencement of
vegetation. The large proportion of water present which characterizes
a plant grown in darkness is here also due to the slowness of the tran-
spiration, and especially to the increase in the absorption.

Esparto-grass.{—Mr. J. Christie gives a careful description and
drawing of the appearance presented under the Microscope of a trans-
verse section of the leaf of the esparto-grass, Macrochloa tenacissima. On
the upper surface of the leaf are a number of deep grooves or furrows,
characteristic of grasses growing in very dry localities. These are
clothed with unicellular hairs. Bands of fusiform cells, with strongly
thickened and lignified walls, stretch from the upper to the lower epiderm,
giving strength and rigidity to the leaf.

B. CRYPTOGAMIA.

Prof. de Bary’s Microscopical Slides.—The collection of micro-
scopical slides made by the late Prof. de Bary in the course of his work
has been purchased by the Trustees of the British Museum. A few
duplicate slides in use for teaching purposes had been acquired by the
Botanical Institute in Strassburg University, and the slides of Bacteria
have been kept by Dr. A. de Bary, of Frankfurt, in whose hands, as a
skilful experimenter in this department of work, they will no doubt
prove fruitful of results. The collection is therefore complete except
the Bacteria, and the following statement of its contents may be of
interest:—The slides of Fungi are 1220 in number, consisting of
283 Peronosporex, 59 Saprolegnieee, 76 Mucorini, 54 Entomophthoree,
321 Ascomycetes, 217 Uredinew, 10 Chytridiex, 67 Ustilaginee,
73 Hymenomyeetes, and 60 Gastromycetes. Of other Cryptogams and
Vascular Plants there are 1808 slides, representing Lichens, Characez,
Algz, Mosses, and Vascular Plants, making in all 8028 belonging to
what may be called for Museum purposes the systematic series, though
of course everybody knows the importance of these slides to the student
of morphology. In addition there are 1112 slides illustrating anatomical

* Rev. Gén. de Bot. (Bonnier), i. (1889) pp. 359-89, 430-7 (2 pls. and 1 fig.).
Cf. this Journal, ante, p. 668. + Paper-trade Rev., xii. (1889) 2 pp. and 1 pl.

ZOOLOGY AND BOTANY, MIOROSCOPY, ETO. 785

and histological subjects, and 289 slides which for convenience may be
classed under Varia. This gives a full total of 4429 slides. Prof. de
Bary’s researches into the life-histories of Fungi, Conjugate, the anatomy
of Vascular Plants, &c., are so well known to be of fundamental import-
ance, that students of Botany in this country may be congratulated on
having access to the authentic material used by the late distinguished
botanist in his work.

Cryptogamia Vascularia.

Antherozoids of Vascular Cryptogams.*—From observations made
chiefly on Ferns (Pteris, Gymnogramme, Aneimia) and Equisetacee,
Herr W. Belajeff supports the conclusion previously arrived at by others,
that in all Vascular Cryptogams the body of the antherozoid is an achro-
matic ribbon, in which a chromatin-filament or body is inclosed. The
chromatin-body is in all cases derived from the nucleus of the mother-
cell, the cilia and the so-called vesicle from the cell-protoplasm.

Sporocarp of Pilularia.t—M. Meunier has followed out in detail the
development of the sporocarp of Pilularia globulifera, which he finds to
agree with the account given by Goebel and Juranyi, except that he was
unable to detect in the youngest conditions examined any connection
with the leaf. Its vascular bundle appears, on the contrary, to spring
directly from the cauline bundle. He agrees with Juranyi in regarding
the sporocarp as corresponding to four divisions of the leaf, rather than
with Goebel, who looks upon it as representing a single division only.
He describes, moreover, the development of the peculiar refringent pris-
matic layer of cells beneath the epiderm of the sporocarp. The appear-
ance is due to a continuous layer of albuminoid granules on the lateral
walls of these cells, which become inclosed in the cell-wall when this
increases in thickness. The development of the envelope of the spores
out of the protoplasm which surrounds them differs in some respects from
that described by Strasburger in the case of Marsilia.

Endoderm of the Stem of Selaginellacew.{—In the stem of Sela-
ginella no definite endoderm has at present been described. M. Leclere
du Sablon finds one in the species examined, S. hortensis, inzequalifolia,
caulescens, and triangularis, but in a position different from that in which
it is ordinarily found. The cells of the trabecules have a suberized
framework, and this constitutes the endoderm ; this framework is slightly
thickened, but does not generally exhibit plication. The external
layer of the central eylinder is the pericycle, in direct contact with the
liber. The cells of the endoderm are therefore, in Selaginella, com-
pletely isolated from one another, and cannot perform their ordinary
mechanical function.

Root of the Filicinee.§s—M. A. Trécul gives the following reasons
in favour of his opinion on the radicular nature of the stolons of Nephro-
lepis, in reply to the views of Lachmann and Van Tieghem: ||—(1) The
different arrangement of the bundles in the mother-stem, and in the
stolons; they are disposed round the pith in the stem, while they forma

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 122-5. Cf. this Journal, ante, p. 552.
+ ‘La Pilulaire, Louvain, 83 pp. and 6 pls. See Bot. Ztg., xlvii. (1889) p. 592.
t Journ. de Bot. (Morot), iii. (1889) pp. 207-8 (1 fig.).

§ Comptes Rendus, eviii. (1889) pp. 1288-91. || Cf. this Journal, 1885, p. 1033.

1889. 31

786 SUMMARY OF CURRENT RESEARCHES RELATING TO

central group in the stolons; (2) the difference in structure of the
bundles in the stem and in the stolons; (3) the absence of roots on the
mother-stem, if the stolons are regarded as of a cauline nature; (4) the
structure is always similar in the roots and in the stems of Ferns; (5)
the roots of second and third order are monostelous, like the stolons.

Algee.
Phyllactidium, Phycopeltis, and Hansgirgia.*—Dr. G. B. Toni

assigns reasons for regarding Phyllactidiwm arundinaceum Mont. as
a species of Phycopeltis, which must now be known as Phycopeltis arun-
dinacea. He does not agree with Hansgirg in identifying Hansgirgia
flabelligera with Phycopeltis. He affirms an important difference between
the two genera, Phycopeltis being reproduced by non-sexual zoospores,
Hansgirgia by sexual zoogametes, like Trentepohlia. Mycoidea he regards
as occupying an intermediate position between the Coleochetacez and
the Gidogoniacee.

Conjugation of Spirogyra.t—Mr. C. B. Atwell describes a case of
conjugation in Spirogyra longata,in which, in two instances, the contents
of a male cell have passed into two female cells, forming a zygosperm
in each.

Volvox minor.{—Prof. J. A. Ryder discusses the fore and aft poles,
the axial differentiation, and a possible anterior sensory apparatus in
V. minor. In every colony there was an empty pole, which was always
anterior ; the direction of the rotation of the colonies is not constant,
and may be either sinistral or dextral; but the direction of progress
always coincides with an imaginary axis passing through the centre
of the anterior empty pole and the posterior germ-bearing portion
of the nearly spherical colony. The diameter of a colony is slightly
longer along the axis round which it revolves than in the direction
transverse to it, so that the form of the whole is that of a very slightly
oblong spheroid. The “eye-spots” found in the flagellate cells of the
anterior pole of the colony were the largest, and as one passes in suc-
cession backwards the spots are seen to gradually diminish in size, until
at last they are barely distinguishable. This arrangement revives the
question as to whether these eye-spots. are not really sensory organs.
Prof. Ryder remarks that he has been unable to find any notice of any
of the features of Volvo here described, and he expresses a hope that
some microscopist will take up the study of Volvox anew, and publish a
well-executed drawing of it.

Fungi.

Blastomyces.§ —MM. J. Costantin and Rolland describe a new genus
of Mucedineze to which they have given the name Blastomyces. The
following is the diagnosis:—A filamentous fungus forming at its ex-
tremity short branches which give rise both to the primary and secondary
spores. Each fructifying branch is thus transformed into a pulverulent
sporiferous mass. Aquatic and aerial chlamydospores on the mycele.

* Bot. Centralbl., xxxix. (1889) pp. 182-4. Cf. this Journal, ante, p. 419.
+ Bot. Gazette, xiv. (1889) p. 154 (1 fig.).

~ Ann. and Mag. Nat. Hist., iv. (1889) pp. 253-4.

§ Rey. Mycol., xi. (1889) p. 166.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 787

One species only is known, to which the authors have given the name of
B. luteus.

Synchytrium alpinum.*—Herr F. Thomas describes this new species
of Synchytrium, parasitic on Viola biflora, on which it produces a large
number of galls on all the parts of the plant above ground.

Ustilaginew.t—Herr O. Brefeld has studied the development of
about forty species of Ustilagineee which he has induced to grow in
artificial nutrient solutions. They exhibit various important differences.
Conids were produced in great quantities,—in Ustilago carbo, U. cruenta,
and U. Maydis beneath the fluid, in Tilletia caries in the air. In the
latter species and its allies mould-like tufts were formed from the conids
of the first culture; in the species of Ustilago named the conids formed
on the short germinating filament of the ustilagospore multiplied rapidly
by direct sprouting at the two ends. Other species, as U. longissima,
grandis, and bromivora, formed conids on the bicellular myceles of the
germinating ustilagospores, which did not sprout directly, but developed
first into new promyceles, on which fresh production of conids took
place. Other species again, as U. Crameri and hypodytes, formed no
conids from ustilagospores which germinated in nutrient solutions, but
only sterile germinating filaments which developed into sterile myceles.

In the case of U. carbo the sprout-conids are produced in an unin-
terrupted succession of generations as the only product in nutrient
solutions outside the host-plant, while within it produces only ustilago-
spores. When the fluid is exhausted the conids put out germinating
filaments. The power of the conids to produce ustilagospores, on which
the infectious property of the fungus depends, was found to be weakened
by time and by continued propagation outside the host-plant.

Ustilago carbo attacks the sheaths only of the oat, and only in a
young state; and this parasite does not attack barley, the rust of this
cereal being caused by a hitherto undescribed species U. Hordei ; its
spores germinated in nutrient solution without producing conids. On
the other hand, all young parts of Sorghum saccharatum are attacked by
U. cruenta. In the oat and millet the germs of the parasite (U. carbo
and cruenta respectively) remain latent in the plant in the first stage of
germination until the production of the sexual organs, when they develope
in the young ovary and destroy the fructification. All parts of the
maize are subject to the attacks of its parasite, U. Maydis, but the
infection remains local.

Pathogenic Fungus from the Human Ear.{—Dr. Lindt has culti-
vated from the human ear a fungus which belongs to the genus
Aspergillus, and has the following characteristics :—Fine short septate
mycele; very short conidiophores, with pyriform ends of 22-24 w in
diameter, and these bear colourless unbranched sterigmata arranged
raliately. The chains of spores are slightly bent away from one
another. The spores, which are small, have a faint green colour. The
colour of the fungus is bluish-green. The peritheces are round,
whitish, 40-60 » large, and enveloped by a thick mycele. ‘The wall
consists of several layers of polyhedral cells. The asci are 14-18 »

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 255-8.
+ ‘Neue Unters. iib. d. Brandpilze u. d. Brandkrankheiten, Band ii., Berlin, 1888.
See Bot. Centralbl., xxxix. (1889) p. 15.
t Arch. f. experiment. Pathologie u. Pharmakologie, xxv. (1889) p. 257.
: ae a

788 SUMMARY OF CURRENT RESEARCHES RELATING TO

large, bizonvex to spherical, and contain eight sporids of 6-8 pu in size.
The fungus developes best at the temperature of the body ; the peritheces
copiously on bread and potato in warmth. When introduced into the
circulation of rabbits the spores killed the animals, which died in three
to four days of a general mycosis.

Parasitism of the Truffile.*—M. H. Bonnet gives several instances
in which truffies have been known to grow quite unconnected with the
roots of any tree. They are generally found under the holm-oak, or
chestnut, and in Europe, Africa, and the United States in the neighbour-
hood of all non-aquatic oaks. The author quotes M. Boudier’s opinion
on the parasitism of the truffle, which is that they must be rather con-
sidered as saprophytes than parasites, and that they live on the humus
occurring in the neighbourhood of roots rather than on the roots them-
selves. As to the mycele, M. Condamy states that there is a female
mycele, a white thread which produces the fruit, and a male mycele
fixed on the roots, the concurrence of which is indispensable for the act
of fecundation.

Fungi parasitic on Trees.t—Herr C. v. Tubeuf describes the fungi
which cause a number of diseases on various trees in Germany. A
prevalent disease of the Douglas-pine t is caused by Botrytis Douglasit
n.sp. Trichospheria parasitica, hitherto known only on the spruce-fir,
occurs also on Picea eacelsa ; and Lophodermium brachysporum must be
added to the enemies of the Weymouth-pine. Two new species are
described :—Pestalozzia Hartigii, parasitic on young plants of Picea
excelsa and Abies peciinata; and P. conorum Picee, on fallen cones of
Picea excelsa.

The author has observed the mycorhiza on the roots of Pinus Cembra
at an altitude of 2200 m., in Tirol. It assumes two forms :—a coral-like
form consisting of fine white and coarser brown filaments, with loop-
cells, penetrating the bark as far as the endoderm; and fine filaments in
the vessels of the swollen lateral roots which have been destroyed by the
fungus.

Fungi parasitic on Rice.§—Herr F. v. Thiimen enumerates thirty-
four species of fungus parasitic on the rice-plant. Of these by far the
most destructive is Spherella Malinveriana, producing the disease known
as ‘‘bianchella,” “selone,’ “crollatura,’ “ brusone,” or ‘“ carolo,”
which annually destroys a large portion of the crop in Austria and
Ttaly.

Echinobotryum and Stysanus. ||—M. J. Costantin claims to have
determined the identity of Echinobotryum atrum and Stysanus Stemonitis.
This result he has obtained by the repeated careful culture of spores of
Echinobotryum. At the end of the fifth day hemispherical tufts make
their appearance, and these are shortly followed by a large number of
conids, and then by the pseudo-capitula. By a series of insensible
transitions the ramifications then appear, the pedicel elongates, and the
transformation to the Stysanus-form takes place.

* Rey. Mycol., xi. (1889) pp. 124-7. Cf. this Journal, 1888, p. 780.

+ ‘ Beitr. z. Kenntniss d. Baumkrankheiten,’ Berlin, 1888, 61 pp. and 5 pls. See
Bot. Centralbl., xxxix. (1889) p. 132. t Cf. this Journal, 1888, p. 471.

§ ‘Die Pilze d. Reispfiinze, 1889, 19 pp. See Bot. Centralbl., xxzix. (1889)
p. 131. | Journ. de Bot. (Morot), iii. (1889) pp. 240-3, 245-7 (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 789

Dr. A. N. Berlese,* has come to the same conclusion, and regards
Echinobotryum atrum as the secondary or chlamydosporal form of Stysanus
Stemonitis. Of the four known species of Echinobotrywm, E. atrum,
leve, Citri, and parasitans, all but EH. leve occur also in a Stilboid form,
E. Citri as Stysanus monilioides, and E. parasitans as S. caput-Meduse.
Stysanus and Pachynocybe differ from one another in the spores being
in chains in the former genus, solitary and acrogenous in the latter.

Prolification in the Hyphomycetes.t—Dr. A. N. Berlese states that
it is not uncommon, in the hyphomycetous fungi, after the production of
conids, for the conidiferous filament to renew its growth, and develope a
second series of filaments. This appears to be a contrivance for main-
taining the fungus in a latent condition until favourable conditions for
germination occur. The phenomenon was observed in Acrothecium atrum,
Hormodendron cladosporioides, Botrytis vulgaris, Rhinotrichum sp. and
Sporochisma mirabile.

Laboulbeniacez.{—Dr. A. N. Berlese gives a careful monograph of
all the known species of this little-known order of Fungi, parasitic on
insects and a few other animals, fifteen in number, mostly found in
Austria, but some also in France, Russia, and America. They are
characterized by having a perithece formed of a small number of cells,
supported on a longer or shorter stalk, and provided laterally with
filiform bodies varying in structure according to the genus. Within the
perithece are fusiform hyaline sporids, septated in the middle and usually
inclosed within asci. They are therefore abnormal Pyrenomycetes, and
must be regarded as an appendix to that order.

A description follows of a new species, Laboulbenia armillaris,
parasitic on Antennophorus, a genus of Acari, in Paraguay; and the
following diagnoses are given of the order and of its six genera.

LABOULBENIACEH. Stipes plerumque inferne bicellularis, nodulose
terminatus. Perithecium conicum, longe ovoideum vel subcylindraceum,
seepe inequilaterale, apice ostiolatum. Sporidia fusiformia, bicellularia,
hyalina. Pseudoparaphyses filiformes, e latere perithecii orientes,
simplices vel ramose.

Laboulbenia. Perithecium apice mammillatum, perforatum. Pseudo-
paraphyses simplices vel ramosz, articulate, tiliformes. 10 species.

Stigmatemyces. Perithecium in parte media incrassatum, in collum
crassum tuberculo conoideo breviter bilobo terminatum desinens.
Appendix lateralis perithecii, sive pseudoparaphysis, curvata, pluriarti-
culata, superne (hoc est in latere convexo) appendiculis acutis ornata,
1 species. ;

Helminthophana, Perithecium subcylindraceum, in collum cylin-
drium poro pertusum desinens. Ostiolum e corona cellulari multilobata
formatum. Pseudoparaphysis ad basim stipitis inserta, subcylindrica,
articulata, appendiculis acutis ornata. 1 species.

Appendiculinz. Perithecium fere globosum, in collum prelongum
fere cylindricum productum. Pseudoparaphysis basi perithecii inserta,
articulata, appendiculigera, Ostiolum (saltem ex diagnosi et figura)
simplex. 1 species. ;

Chitonomyces. Perithecium apice trilobum. Lobus medius apice

* Malpighia, iii. (1889) pp. 243-51 (1 pl.). ‘+t T.¢., pp. 251-9 (1 pl.).
t T.c., pp. 44-60 (1 pi.).

790 SUMMARY OF CURRENT RESEARCHES RELATING TO

ruptus et sporidia emittens. Pseudoparaphysis lateralis, simplex, non
articulata, coe nonnullis appendiculis tuberculiformibus preedita.
1 species.

Heimatom yces. Perithecium apice in cornu lateraliter pertusum
productum. Pseudoparaphysis lateralis uniarticulata. 1 species.

Cotemporaneous action of different kinds of Saccharomyces.*— It
has already been shown, says M. J. Vuylsteke, by Hansen, that in a
mixture of low ferments and wild Saccharomyces the proportion of the
cells of the latter was always greater at the end of fermentation than at
the beginning. The comparison was made with the low yeasts
Carlsberg i. and Carlsberg ii., with §. Pastorianus i. and iii., and
S. ellipsoideus ii. The author's experiments were made with one high
and two wild ferments, S. cerevisiz 1. and S. Pastorianus i. and iii. The
results obtained by the author were as follows:—a ereater infection at
the end than at the beginning of fermentation was not always found with
S. cerevisie i. and S. Pastorianus 1., but the law laid down by Hansen
for the low and wild species was found to hold good for S. cerevisiz 1.
and Pastorianus ili.

The method adopted by the author in his experiments was to take
vessels holding about two litres, and fill them two-thirds with hopped
wort of a density of 14 per cent. Balling. These vessels and contents
were then sterilized more or less, by heating them for two or three hours
to 70°-90° C. From the scum obtained by inoculating with pure
cultivations of the different yeasts, a certain quantity was pipetted off at
the beginning of fermentation, and also at the end.

The proportion was calculated by two methods, the first of which was
based on direct enumeration, and the second on the formation of
ascospores. ‘The second method is compulsory when a Burton or
Carlsberg i. ferment is used, since these latter tend to assume the
elongated form during the principal fermentation. In both cases the
method given by Hansen was adopted.

Himalayan Uredinexw.t—Dr. A. Barclay describes sixteen species of
Uredinez from Simla (Western Himalaya). The following are new :—
Aicidium Sanicule on Sanicula europea (probably connected genetically
with Puccinia Pimpinelle), Puccinia Fragarie on Fragaria vesca, Aicidium
Jasmini on Jasminum humile, Monosporidium Euphorbiz gen. et sp. nov. on
Euphorbia cognata, M. Andrachnis on Andrachne cordifolia. Monospori-
dium is characterized by the spores being abstricted in rows, but behaving
in germination somewhat like teleutospores. The germ- tube produces at
its extremity a secondary non-deciduous spore without the intervention
of a sterigma.

Rostrupia, a new genus of Uredines.t—Prot. G. v. Lagerheim
identifies Puccinia triarticulata B. & C. with P. Elymi West., and estab-
lishes it as a type of a new genus of Uredinez (Rostrupia) with the
following diagnosis :—Sori uredosporiferi explanati, ureodosporis apice
pedicelli solitariis; sori teleutosporiferi explanati; teleutospore sim-
plices, 2-pluries septate (rarissime uniseptate), quoque loculo porum
singulum germinationis gerente. Aicidia adhuc ignota, veresimiliter (ut
in generibus Uromyces et Puccinia) pseudoperidio instructa et paraphysibus

* Ann. de Microgr., ii. (1889) pp. 190-218.

+ Journ. Asiatic ‘Boe. Bengal, lvi. (1887) pp. 350-75 (4 pls.).
{ Journ. de Bot, (Morot), ii. (1889) pp. 185-9 (1 fig.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 791

destituta. Two species are described :—R. Elymi parasitic on Elymus
arenaria and E. mollis, and R. tomipara (Puccinia tomipara Trel.) parasitic
on a Bromus.

Subepidermal Rusts.*—Mr. H. L. Bolley states that he has been
making a structural study of the teleutospore stage of Puccinia coronata
and P. rubiga-vera, upon different hosts, with the hope of being able to
obtain some differentiating structural characteristics. The results
obtained, however, have been negative; for structural variations which
were often quite marked upon some hosts were either absent from others
or so slight as to be of no comparative value. In most species of
Uredinex, the teleutospores break through the epiderm of the host-
plant; but in both the species mentioned they reach maturity in the
matrix or sorus without rupturing the inclosing epiderm, a condition
which is typical of a number of other species, and which, for the con-
venience of this paper, has been termed “subepidermal.” These
species present many common peculiarities of form and structure. In
some cases, as P. coronata and P. rubigo-vera, species grade the one into
the other so closely as to nearly defy separation upon a structural
basis. The author also describes the various spore-forms to be found
among the subepidermal rusts; and concludes by discussing in detail
the development and structure of the stroma.

Cultures of Gymnosporangium.{—From the cultivation of various
American species of Gymnosporangium, Mr. R. Thaxter has come to the
conclusion that the true Roestelia penicillata is not at present known in
that country; that R. lacerata is incorrectly named, and is the ecidium
of G. globosum; and that R. botryapites is genetically connected with G.
biseptatum, and R. aurantiaca with G. clavipes. RR. cornuta is connected
with either G. globosum or G. conicum.

Ravenelia.t—Dr. D. D. Cunningham describes in detail the lif>-
history of two species of Ravenelia common in the neighbourhood of
Calcutta, R. sessilis and R. stictica. Each species produces two forms of
uredospore and two forms of teleutospore, as well as “ spermatia ” con-
tained in spermogones, but the ecidial generation is apparently entirely
wanting. Otherwise they correspond to the normal type of Uredinee.

Czeoma Smilacinis.s—Dr. A. Barclay describes a hitherto unknown
species of Czoma which attacks the leaves of Smilaw aspera at Simla
(N.W. Himalayas). He believes it to be the first completely autcecious
species of Cxeoma yet described, the uredo-form and ecidio-form being
parasitic on the same plant. The ecidial form begins to appear in June
or July, and the leaves which bear it drop off in October or November.
In October the uredospore-form begins to appear in distinct patches
on the same leaves. The formation of teleutospores commences in
November.

Macrosporium parasiticum.||—Mr. A. E. Shipley describes the life-
history of this fungus, found abundantly on diseased onions in the

* Bot. Gazette, xiv. (1889) pp. 139-44 (1 pl.).

+ T.c, pp. 163-72. Cf. this Journal, 1887, p. 445.

t Scient. Mem. by Medical Officers of the Army of India, 1889, 15 pp. and 2 pls.
Cf. this Journal, 1887, p. 446.

§ Scient. Mem. by Medical Officers of the Army of India, 1889, 9 pp. and 2 pls

|| Ann. of Bot., ili. (1889) pp. 268-71. Cf. this Journal, ante, p. 562,

792 SUMMARY OF CURRENT RESEARCHES RELATING TO

Bermudas. He shows, however, that the very destructive disease to
which the crop is subject in those islands is due to the attacks of the
white mildew, Peronospora Schleideniana ; the black mildew, or Macro-
sporium parasiticum, appearing only on-plants already enfeebled by
disease.

Peach-Yellow.*—Mr. E. F. Smith gives a preliminary report on a
disease which affects peach-trees in the United States. It is not certain
whether peach-yellow is due to a fungus or to bacteria, but the author gives
a list of the fungi which attack peach-trees. Taphrina deformans Tul. is
found on the leaves; Sphzrotheca pannosa Levy. also attacks the leaves ;
while Puccinia Pruni spinose P. brings about their premature fall;
Oidium fructigenum Kaze. et Sch. attacks the fruit; Cladosporium
carpophyllum Thiim. developes on the surface of the leaves and fruit ;
Ascospora Persice Sacc. is found on the lower surface of the leaves;
and finally Capnodium elongatum Bk. et Desm. and Polyporus versicolor
Fr. are also found on the peach.

Boletopsis, a new Genus of Hymenomycetes.;—M. V. Fayod
separates from the genus Polyporus P. meluleucus Pers., in consequence
of the character of the spores, which, instead of being white and ovoid,
are angular, and when seen in quantities, flesh-coloured. The following
is his diagnosis of the new genus :—

Boletopsis. Thallus carnoso-lentus subnudus (cuticula pilei adum-
brata), pileo (semper) centraliter stipitato, strato tubulifero tenui, carneo,
inseparabili. Poris albis, minutis, dein laceratis. T'rama homomorpha,
densa, e hypbis tenuibus plus minusve dispersis, subbymenio carens.
Basidia 2—4 stigmatica, parvula. Spore gibbose-angulose, carnee.

Dispersion of the Spores of Fungi by Insects.{—Dr. T. W. Fulton
describes the rapid growth, immediately before maturity, of the hymeno-
phore of Phallus impudicus, and the mode in which it deliquesces when
the spores are ripe. The fetid fluid thus formed is exceedingly
attractive to flies, which carry away enormous numbers of spores,
both attached to and within their bodies. It was ascertained by experi-
ment that passage through the body of a fly does not destroy the vitality
of the spores.

Other contrivances for attracting flies for a similar purpose, such as
a flower-like form or bright colour of the receptacle, are, according to
the author, manifested by others of the Phalloidee and by species of
Coprinus.

Mycetozoa.

Colouring-matters of Mycetozoa.S—Prof. W. Zopf gives an account
of the lipochromes or fatty pigments found in various species of
Mycetozoa, especially in the following :—Stemonitis ferruginea, 8. fusca,
Lycogala epidendron, L. flavo-fuscum. The more important general
results of the investigation are stated to be that the pigment in all these
four species belongs to the yellow series. The spectrum of the pure
lipochrome of Lycogala shows several peculiarities. Besides the two
well-known absorption-bands, one in F, the other between F and G,

‘ Peach-yellow,’ Washington, 1888. See Rev. Mycol., xi. (1889) pp. 160-3.
Malpighia, iii. (1889) pp. 69-73 (3 figs.).

Ann. of Bot., iii. (1889) pp. 207-37 (1 pl.).

Flora, Ixxii. (1889) pp. 353-61 (1 fig.). Cf. this Journal, «ante, p. 560.

Qt qe ¥

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 793

belonging to all yellow fatty pigments, there are two additional ones,
one at G, the other between E and b. In addition to the lipochrome,
there was found, in each of the four species examined, an amorphous
pigment soluble in water, and of an acid character.

Protophyta.
a, Schizophycee.

Growth of the Cell-wall by Intussusception in some Schizo-
phycee.*—Herr C. Correns states that in Gleocapsa and Petalonema
certain definite layers of the cell-wall increase in volume, although
separated by similar layers from the protoplasm of the cell. .Since this
is not accompanied by swelling, it can only be brought about by the
intercalation of water and particles of substance between those already
in existence. The proofs that the increase in size is not the result of
swelling are given in detail.

In Petalonema it is not the apical cell alone, but all its segments to
a certain distance from the apex that divide. The gelatinous sheaths
are formed from the apex, and are usually of a funnel-shape, and
probably formed by apposition. The entire sheath is inclosed in a
pellicle, which, through growth by intussusception, keeps pace in
volume with the sheath, and is not burst or broken through by the
growth of the funnels. The sheath, and especially the junction of the
inner and outer sheath, is coloured yellow or brown-yellow by scyto-
nemin. The presence of the pellicle and the thickness of the sheath
distinguish Petalonema from Scytonema.

Prasiola.t—Herr L. Imhiuser separates Prasiola from the Ulvacee,
and erects it, possibly along with Protoderma and Schizomeris, into a
distinct family of PrastoLacea@, nearly allied to Palmellacee. All the
species consist, when mature, of a larger or smaller plate of cells; and
are distinguished from the Ulvacez by the mode of reproduction, which
is a purely non-sexual one, and takes place by the plate breaking up
into larger or smaller areole, or more usually into single cells; less
often filaments of cells are split off. From the isolated cell is always
developed a filament, which then grows into a plate. Hormidium and
Schizogonium are merely stages in the development of these plates.
The following six species are described, the first alone being free, all the
rest attached :—P. crispa, furfuracea, stipitata, Sauteri, calophylla, and
mexicana.

Heterocystous Nostocacee.{—Supplementing Bornet and Flahault’s
monograph of the heterocystous Nostocacez contained in the herbaria of
France, M. E. Bornet now describes the specimens contained in the
herbarium of Agardh, many of which are the type-specimens of the
Systema Algarum.

Movements of Diatoms.§—From observations made on various species
of Navicula, especially of the sub-genus Pinnularia, Herr O. Miiller
confirms his previous hypothesis that the movements of these diatoms
are connected with perforations in the cell-wall. He finds that immer-

* Flora, Ixxii. (1889) pp. 298-347 (1 pl.?. + T.c¢, pp. 233-90 (4 pls.).

{ Bull. Soc. Bot. France, xxxvi. (1889) pp. 144-57. Cf. this Journal, 1888,
p. 472. ;
§ Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 169-80 (1 pl.).

794 SUMMARY OF CURRENT RESEARCHES RELATING TO

sion in a weak solution of sodium chloride causes immediate suspension
of the movement, which commences again on immersion in pure water ;
from which he concludes that it is nct the result of osmotic processes.
The interior protoplasm appears to have a tension of 4-5 atmospheres,
which would cause it to rush out through the openings in the valve, if
the channels which lead to these openings were not of a winding and
complicated character. He believes rather that the movement itself and
the direction of this movement are the result of motor forces which
are manifested on the surface, residing in the protoplasm which is pro-
truded through the raphe.

Auxospore of Terpsinoé.*—Herr O. Miiller describes the auxospore
of Terpsinoé musica from St. Domingo. The length of the valve of the
auxospore varies between 223 and 257 yp, while that of the mother-cell is
only from 92 to 106 ». The formation takes place on the same general
plan as that of Melostra, and is a process of simple rejuvenescence rather
than of sexual reproduction. The mass of protoplasm which expands
and projects between the valves of the mother-cell fills up the older half
of this cell, withdrawing itself entirely from the younger half; the
perizone surrounding the portion of the protoplast which adheres to
the older half. The new girdle is formed in the portion of the proto-
plasm surrounded by the perizone which faces the younger half, and
this is followed by the excretion of the second auxospore-valve. In
the genus Terpsinoe the cavity of the valves is divided by septa, the
purpose of which is to bring the chromatophores into a profile-position
under the powerful tropical insolation.

Diatom-beds of the Yellowstone.;—Mr. W. H. Weed describes the
composition of the enormous diatom-marshes and diatom-beds of the
Yellowstone National Park, U.S. He finds them to consist mainly of
the following species :—Denticula valida and elegans, Navicula major
and wiridis, Epithemia argus and var. amphicephala and HE. Hyndmannii,
Cocconema cymbiforme, Achnanthes gibberula, Mastigloia Smithii, and
Fragillaria sp., of which the first is the most abundant.

B. Schizomycetes.

Micro-organisms and their Destruction.t—Dr. A. B. Griffiths, who
has continued his researches on micro-organisms, thinks that as the
microbes, which are the real cause of certain contagious diseases, may be
destroyed by various germicides, we ought, by further investigation, to
discover remedies for such scourges as consumption and syphilis. The
author finds that the vitality of Bacillus tuberculosis is considerable, and
that it is capable of being dried up in the atmosphere for many weeks
without its vitality being impaired. The electric current destroys the
vitality of certain microbes. Dr. Griffiths has discovered that a new
microbe, which he calls Bacterium allium, is the cause of putrefaction in
the onion, and that it liberates small quantities of sulphuretted hydrogen.
The soluble zymoses secreted by living microbes are capable of being
destroyed by germicidal agents, and are thus rendered incapable of pro-
ducing chemico-pathological changes in the blood-tissues.

* Ber. Deutsch. Bot. Gesell., vii. (1889) pp. 181-3 (1 pl.).
+ Bot. Gazette, xiv. (1889) pp. 117-20.
{ Proc. R. Soc. Edinb., xv. (1888-9) pp. 33-65.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 795

Micro-organism found in the mucous flux of Trees.*—In 1886 Prof.
Ludwig described an alcoholic fermentation and mucilage which he had
observed in certain trees, and expressed the opinion that the fermenta-
tion was due to a fungus which he called Endomyces Magnusii. Besides
this, two other Saccharomycetes and a new Schizomycete, Leuconostoc
Lagerheimii, were noted. From further observations, published in 1888,
Prof. Ludwig concluded that the mucilage was due to Bacteria.

Dr. E. C. Hansen now describes the mucilage which he has observed
in seventeen cases, and in only one of these was the Endomyces Magnusii
found; hence this author points out that it cannot be considered the
cause of the flux. Owing to the number of different animal and
vegetable parasites in these seventeen cases, Hansen concludes that it
would uot be safe to infer that any one was the specific cause of the
mucilage, but is of opinion that, considering the cause of “ pear-blight”’
has been shown to be a bacterium, the Micrococcus amylovorus, it is
probable that a bacterium should be sought for as the cause.

He then goes on to discuss one of the Saccharomycetes found by
Ludwig in the seum on the trees. The latter considered this Saccharo-
myces to be a developmental stage of Endomyces and its Oidium. The
question Hansen resolves into:—Can the Oidium-form be made to
develope into the Endomyces-form ? can the Saccharomyces be developed
from the Oidium, and conversely, if starting from the Saccharomyces,
can the Oidiwm and Endomyces be obtained? These questions are
answered in the negative.

Still more recently, Prof. F. Ludwig ¢ has made further contributions
to the pathogenesis of this disorder, and he states that the mucous flux
is produced by the symbiotic schizomycete, Leuconostoc Lagerheimit.

Considering, however, the number of micro-organisms and their
great differences, the question would not appear to be at present
answered satisfactorily.

Pleomorphism of Bacteria.{—M. Metschnikoff replies in an article
on the pleomorphism of Bacteria to the theories enunciated by Wino-
gradsky.

Spirobacillus Cienkowski, which was made the subject of examination,
justifies its name, as it passes successively through the stages of Bac-
terium, Bacillus, and Spirillum. This parasite attacks the small aquatic
crustacean Daphnia, and imparts to it its red colour.

The author was able to follow the transformation of the Bacteria
through the different phases of the disease: the stages figured seem to
form tue transition between the most distant forms. The author’s results
were, however, not obtained by cultivations, consequently they are not
altogether convincing.

Movements of Micrococci.$—It is usualiy accepted, says Dr. C. H.
Ali-Cohen, that micrococci are not endowed with any characteristic
movements. There are, however, no a priori considerations why this
kind of Bacteria should differ from other kinds; that is, why a spheroidal
microbe should be iucapable of motion, while an oval or rod-like one
should be gifted with specific movements.

* Centralbl. f. Bakteriol. u. Parasitenk., v. (1889) pp. 632-40, 663-67, 693-6.
Cf. this Journal, 1887, p. 285. t J..c., vi. (1889) pp. 133-7, 162-5.

{ Ann. Inst. Pasteur, 1889. Cf Bull. Soc. Bot. France, xxxvi. (1889) p. 51.

§ Centralbl. f. Bakteriol. u. Parasitenk., vi. (1889) pp. 33-6.

796 SUMMARY OF OURRENT RESEARCHES RELATING TO

The author has been able to breed from drinking-water cocei which
are possessed of a high degree of movement. Though almost always
diplococci, they sometimes appear as streptococci, and betimes as tetrads ;
their diameter is 1 ». The double cocci are clearly divided by a fissure,
and, both in the unstained and in preparations stained with fuchsin or
by Gram’s method, their coccus form is indisputable. Their form is
easily cultivated at the ordinary temperature in gelatin-agar, potato-
paste, &c., but does not grow at the body temperature. They liquefy
gelatin, but only very slowly. Though the cocci themselves seem to be
colourless, they always produce a rose-coloured pigment. The peculiar
motion with which they are endowed is easily observed in drop-culti-
vations. This is best seen in 5 per cent. milk-sugar-agar, wherein it is
kept up for several days.

The movements are swimming in character, various in direction, and
of a rapidity of about 10 asecond. Anything which lessens the vitality
of the cocci diminishes the movements, and they cease altogether in
1 per 1000 HgCl,, 5 per cent. carbolic acid, dilute sulphuric acid, or if
killed by heat, though the molecular movements still go on.

These two kinds of movements can be differentiated by increasing
the viscosity of the fluid ; for, as this is increased, so the molecular move-
ments diminish. Again, the more the drops are cooled down, the more
the viscosity increases, until finally the Brownian movements cease
altogether. At this point the specific movements are still going on, and
only cease when the drop has become solid.

To this fungus the author gives the name of Micrococcus agilis.

Variability of Bacillus anthracis. *—M. A. Chauveau has continued
his important investigations into the conversion of pathogenetic microbes.
He finds that by continuing the action of compressed oxygen on cultiva-
tions of developing Bacillus anthracis, he is able to form races or types,
which offer less resistance than the primitive Bacillus, and are particularly
sensitive to the action of the attenuating agent to which the Bacillus owes
its new properties. If the influence of the attenuating agent is continued,
the new types finally lose their power of growing when brought into con-
tact with it; but so long as the Bacillus does not pass the limits of vege-
tability, it remains among pathogenetic agents. It is true that it loses
all its virulent properties, but it completely preserves the vaccinal
property, and preserves it almost intact during the whole period of its
existence. These new characters are definite, and may be easily brought
about by cultivation in successive generations. If we were to take
no account of their origin, we might regard these types by themselves as
forming distinct species. It is not impossible that special types of
Bacillus anthracis do exist in nature with properties absolutely identical
with those of the races which have been made in the laboratory.

New Bovine Tubercle Bacillus.t—M. J. Courmont has found a new
tubercle bacillus in the pleura of an ox attacked with “ pommeliére.”

The bacillus is short and broad, and consists of a clear median zone,
slightly constricted, and of two terniinal nuclei (? spores). It is very
mobile, grows rapidly on all the media usually employed, and does not
liquefy gelatin. Cultivations were obtained at 46°, and in vacuo. It is
easily stained and decolorized. The tubercles of the ox, when not mixed
with the bacillus of Koch, gave pure cultivations straight away.

* Comptes Rendus, cix. (1889) pp. 554-9. t+ T.c., pp. 160-2.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 797

Rabbits inoculated with juice from the tubercles became tuberculous
in fifteen to twenty-four days; while guinea-pigs died in the first ten
days, presenting simply a local oedema and swelling of the spleen. The
tubercles from the rabbits gave pure cultivations of this bacillus, never
that of Koch; but the blood of both rabbits and guinea-pigs swarmed
with the microbe.

A particular point in the history of this new bacillus relates to the
action of the secretions produced in the organism. Far from vaccinating
the inoculated animal, these secretions prepare the soil for the multipli-
cation of the microbe.

Relation of the Bacilli of the Aleppo Pine to the living tissues.*—
M. P. Vuillemin, who had previously demonstrated that the excrescences
on the Aleppo pine were due to the penetration of a bacillus into the
cambium, has now shown the way in which the microbes arrive there,
and what relations they contract with the living elements. On the
diseased branches are seen crateriform projections about the size of pins’
heads. In the centre of these bosses is a canal, which would seem to
have been made by the proboscis of some insect. The tissue of the boss,
that which bounds the central canal, is practically cicatricial, and when
attacked by the bacillus, the regularity of the healing process is inter-
rupted. It would appear that the bacilli gain entrance through the
canal, although in the youngest wounds the zoogloa are not in imme-
diate contact with the crater. They are, however, close to it, and seem
to occupy exclusively the intercellular spaces; and in their immediate
neighbourhood there is evidence always of considerable inflammation.
Owing to the manner in which the cicatrization tends to impede the
progress of the development of the bacillus, three varieties of tumour
are distinguished: tumours originating from the cambium and from the
cortex, and those of a mixed type. In every case the bacilli remain
confined between the cells as long as these are alive. Hence it is through
the cellulose wall that specific action is exerted, and the history of this
disease affords support to the doctrine which attributes a toxic influence
to the fluids excreted by pathogenic bacteria.

Cholera Bacillus.t—Dr. D. D. Cunningham has made a series of
experiments with the cholera bacillus, in order to determine if the microbe
be the efficient cause of epidemic cholera,

The experiments indicate that when introduced into soil and water
of very different qualities, the comma bacilli tend to disappear very
rapidly.

The author then proceeds to discuss the theories of Koch and Hueppe,
and finally concludes that, “ view the question as we may, the paramount
importance of local conditions, and the subordinate and secondary role
which the comma bacilli must play in reference to epidemic diffusion of
cholera, is very evident.”

Preventive Inoculations.t—We can only call attention to Dr. E.
Roux’s “Croonian Lecture,” which may be recommended as giving a
general conspectus of the theories and mode of work of M. Pasteur.

* Comptes Rendus, evii. (1888) pp. 1184-6.
t Scieut. Mem. by Medical Officers of the Army of India, 1889, 20 pp.
$ Proc. Roy. Soc., xlvi. (1889) pp. 154-72.

798 SUMMARY OF CURRENT RESEARCHES RELATING TO

Antagonism of the Bacillus of Blue Pus and Anthrax.*—Dr. E. de
Freudenreich confirms in the main the results of Prof. Bouchard on the
antagonism between the bacilli of blue pus and anthrax. The experi-
ments of the latter gave a resistance of 46 per cent., but the author’s
percentage falls to 28. The greater the amount of the blue pus virus
injected, the greater the immunity. On the other hand, it was found
that if the quantity injected was small, the anthrax pursued its fatal
course unchecked. It is suggested, basing the supposition on the
doctrine of phagocytes, that the cells had not been sufficiently stimu-

lated by the blue pus, and hence were not fully awakened to their
responsibilities.

* Ann. de Microgr., ii. (1889) pp. 465-9.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 799

MICROSCOPY.
a, Instruments, Accessories, &c.*
(1) Stands.

Anderson’s “Panoramic Arrangement for the Microscope.” t—
Prof. R. J. Anderson’s apparatus (fig. 97) “consists of a circular dise,

Fic. 97.

which is made to revolve by means of ahandle. The disc is fixed to one
extremity of an axle, and the handle to the other. The axle has a

* This subdivision contains (1) Stands; (2) Eye-pieces and Objectives; (3) Ilu-
minating and other Apparatus; (4) Photomierography; (5) Microscopical Optics
and Manipulation ; (6) Miscellaneous.

t Internat. Monatschr. Anat. u. Physiol., vi. (1889) 2 pp. and 1 pl.

800 SUMMARY OF CURRENT RESEARCHES RELATING TO

telescopic arrangement by which the disc is approximated to the handle
or removed farther from it. The disc is brought near to the handle by
means of a screw-nut fixed at the end of the inner part of the axle, and it
is moved away by means of a concealed spring. The amount of this
motion is not more than three millimetres. The disc and axle are fitted
on a strong iron stand, supplied with levelling screws.

The frame is so arranged that the disc may be used in the vertical or
in the horizontal position. The vertical position is, perhaps, the most
convenient for museum demonstration. The apparatus, when used in
this position for museum demonstration, is placed in a closed case. The
handle, with its binding screw and focusing button, are the only parts
of the apparatus outside the case.

The disc is furnished with slides. These are clipped to the face of
the disc by means of a segmented ring. The upper surface of each
specimen is turned towards the observer, so that the thickness of the
slide is not involved in the focusing adjustments. ‘The disc must be so
placed that it will be perfectly parallel to the front of the case, and the
light must fall on the face of the disc. The former condition is secured
by means of the levelling screws and a square, and the latter by having
the case in front of a window.

The Microscope is fitted to a brass plate which slides in a second
plate fixed to the front of the case on the same level as the axle of the
apparatus, and at a distance equal to the semi-diameter of the disc. A
lateral motion of the Microscope is best caused by a wheel and rachet
arrangement. ‘The possible movement is one inch.

The Microscope, then, being fixed for any specimen, it is evident
that the screw button on the axis serves to focus the specimen, and is
similar to a fine-adjustment. Secondly, a specimen may be examined
from side to side by means of the lateral motion of the Microscope.
Thirdly, the specimen may be swept from above down by the handle
moving the disc ; and lastly, a whole series may be examined one after
another. It is quite safe to place the instrument in a museum case.
No one can injure the slides or spoil the Microscope, as the limits of
motion are fixed, and the student can thus study a series of specimens
without supervision.

The instrument may be used in the same position for class demon-
stration, or it may be turned, levelled, and thus used in the horizontal
position by means of an ordinary arrangement for reflected light.

The Microscope tube is, under ordinary circumstances, so close to the
vertical portion of the stand, that a special stand is necessary for use in
the horizontal position.

The museum case should be provided with curtains, as some preserved
specimens are injured by the light and heat.”

Nelson-Curties Microscope (Large Model).— This Microscope
(fig. 98) is the joint production of Mr, E. M. Nelson and Mr. C. L.
Curties.* It stands on a firm tripod foot, the extremities of which are
plugged with cork, diminishing vibration and preventing it slipping or
injuring a table. Depending from the trunnions is a kind of stirrup, to
which the Microscope is attached. This stirrup lowers the centre of
gravity when the Microscope is vertical or in an inclined position, and
gives a better balance when the instrument is horizontal for photo-

* See this Journal, 1888, p. 691. 7

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 801

micrography or other purposes. The body can be clamped by means of
a lever attached to one of the trunnions. The body is specially con-
structed to work with Abbe-Zeiss apochromatic objectives, and is
fitted with a rackwork draw-tube for lens adjustment; it will rack out
sufficiently to adjusteshese lenses on the thinnest covers,

Fig. 98,

There is the usual rackwork coarse-adjustment. The fine-adjust-
ment is a Campbell differential screw. ‘This fine-adjustment, while
being very strong, works with great smoothness and delicacy. It is
claimed that the differential screw solves the difficulty which has always

1889. 3K

802 SUMMARY OF CURRENT RESEARCHES RELATING TO

existed with direct-acting screw fine-adjustments, viz. that of providing
a slow movement by means of coarse strong threads; in all other direct-
acting screw fine-adjustments, if they are slow enough to work wide-
angled oil-immersion objectives, the movement is obtained by means of
a micrometer-screw with a very fine thread, which is too weak to stand
the usual wear and tear. The milled head of the fine-adjustment is
placed below the limb. In this new position it is found to be quite con-
venient for ordinary work, while it is steadier when a cord is attached
for phetomicrography.
The stage is plain rotary, having Mayall’s mechanical movement
attached ; it can be clamped
Fic. 99. ; by the screw in front. The
substage has centering
movements, rack-and-pinion
coarse - adjustment, and
differential - screw fine-ad-
justment, admitting of
wide - angled condensers
being easily focused. The
usual plane and concave
mirrors on a double-jointed
arm are carried on an ad-
justable hinged tail-piece.

Edinburgh Student’s
Microscope.—This Micro-
scope (figs. 99 and 100) has
been made by Messrs. W.
Watson and Sons, on lines
suggested by Dr. Hdington,
Lecturer on Bacteriology
at Edinburgh University.
Fig. 99 shows the instru-
ment in its simplest form,
with sliding body for
coarse-adjustment, Conti-
nental horse-shoe foot, and
body - tube of the Conti-
nental size, fitted with
draw-tube, which, when ex-
tended, gives the full
English length of 10 in.
The fine-adjustment—a part
often neglected in instru-
ments of Continental make
—is worked by the rota-
tion of a milled head acting
on a lever moving the
entire body. A tenth of a

turn of the milled head
only moves the body 1/8000 in. so that a precise adjustment
can be made.

Another point is the hanging of the under-stage, fitted on a pivot
so that it can be lifted aside with a condenser in it, and direct light

|

= a |

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 803

from the mirror obtained at once. Fig. 100 is view of the under side,
and shows the way in which it is done. This is a distinct advantage,
and workers with the ordinary form of instrument, in which the con-

Fic. 100.

f)
i )
TDILUTNONENREDNATATULUUIHL

Hi
—

denser must be withdrawn if direct light from the mirror is required,
will at once appreciate it. The stage of the instrument is 3} in.
square, permitting of the use of large slips. The eye-pieces supplied
with the instrument are nickel-plated.

Leach’s Improved Lantern Microscope.—The principle upon which
this Microscope (figs. 101-103) is constructed, was briefly described in
a paper which Mr. W. Leach read before the Manchester Microscopical
Society in 1887, an abstract of which appeared in this Journal.*
There was no thought when this paper was read of placing the Micro-
scope in the market; but the great amount of private correspondence
which followed its publication, led to the instrument being manufactured
for sale.

The stage used in it was an old and well-known form; but it failed
to give satisfaction on account of the obstacles which the object-holder,
with its four arms and the springs coiled round, offered both to the
changing of the sub-condensers through the stage, and to the attachment
of a rotating tube for polarizing prism. To get rid of these obstacles a
new arrangement of object-holder has been devised and placed under-
neath the stage, the arms passing through slots in the bottom, so as to
hold the objects against the inside surface of the front of the stage.
The new object-holder is thus placed out of the way of all the mechanism
and all the material used in the stage. In changing the sub-condensers,
all which it is now necessary to do is to take out the one in use and
substitute the other, neither object, objective, nor wheel of diaphragms
being disturbed in doing so.

The compound wheel of diaphragms is peculiar in its construction.
One part of it has a large single aperture, and moves by means of an
arm upon a pivot, so that it can be lifted up out of the field or dropped
into it, just as it is or isnot wanted. A spring catch holds it up in its
place, so that it cannot fall by its own weight. ‘To the armed wheel is
attached a second wheel with five concentric apertures, any of which can

* See this Journal, 1887, p. 1019.

on ke 2

804 SUMMARY OF CURRENT RESEARCHES RELATING TO

be turned into the centre of the field at pleasure. When the compound
wheel is lifted up as shown in fig. 103, the whole field of the Microscope
can be utilized for showing objects up to 14 in. diameter. Thus the
compound wheel, 24 in. diameter, yields just as large a field as can be
obtained by one of the ordinary form when 5 in. diameter.

Fig. 101,

When, as in using polarized light, it is not desired to be incommoded
with the wheel of diaphragms, the detachable plate carrying the com-
pound wheel can be instantly taken out of the stage, and when taken
out can be as quickly put in again. It should be noted that one stage
serves for all classes of objects, whether ordinary slides or polariscope
crystals shown with narrow-angle rays or the convergent system of
lenses. The tube for the polarizing prism is fitted for entire rotation,
and all the phenomena of polarized light can be demonstrated by the

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 805

iastrument. It is also equally useful for photomicrography, as the
optical principle is based upon the system introduced by the late
Rev. T. W. Kingsley, but greatly improved in both optical and
mechanical effects.

Fig. 101 will give an idea of the way in which the arrangement is
made, a paraffin lamp with 1/2 in. wick being the source of illumination

for this purpose. ‘The instrument having been constructed by a
working man (an operative photographer) who has devoted to it all his
leisure hours for a period of over ten years, it has been deemed only
fair that he should seek some remuneration for his labour, and he has
therefore secured his improvements to himself by a patent.” *

«“ AMATEUR.’—Notes on the Microscope Stand and some of its Accessories. III.
The Microscope, 1X. (1889) pp. 330-6.
Crisp, F.—Ancient Microscopes. Proc. Royal Institution, XII. (1889) p. 201.

Seibert’s Microscope.

(“By means of an improved Microscope made by Seibert of Wetzlar the
internal structure of the anthrax bacillus can be made out. This consists of
a series of pearl-like corpuscles, which can be plainly seen to undergo
division. The magnifying power of the Microscope is said to be 2250
diameters.” Lancet, II. (1889) p. 887.

(2) Eye-pieces and Objectives.

1/10 in. Apochromatic Objective of N-A. 1° 63.—Prof. Abbe has
designed, and Dr. Zeiss has produced a 1/10 in. apochromatic objective
of the large numerical aperture of 1-63, the limit hitherto reached having
been N.A. 1°50 in the case of an objective made by Mr. T. Powell.
Monobromide of naphthaline is used as the immersion fluid, and the
slides and cover-glass are made of flint glass.

An immersion condenser of N.A. 1+60 has also been constructed by
Dr. Zeiss in order to secure approximately the full aperture of the -
objective.

Dr. H. van Heurck reports { that the objective allows of the
resolution of all known tests by axial illumination, and shows new
details in certain Bacteria.

* Of. Eng. Mech., 1. (1889) pp. 242-3 (3 figs.).
+ Bull. Soc. Belg. Micr., xv. (1889) pp. 69-71.

806 SUMMARY OF CURRENT RESEARCHES RELATING TO

Dr. J. Pelletan refers* to the price of the objective as beimg
10,000 franes, or 4001., but we have no verification of this statement.

Apochromatic Objective stolen. [“From the K. mechanisch-technischen Versuchs-~
Anstalt in Berlin-Charlottenburg has been lately stolen an a) oehromatic objec-
tive of Carl Zeiss of Jena, homogeneous immersion, numerical aperture 1°30,
focal length 2mm. Besides the name of the firm and the usual data, the objec-
tive has the maker’s number 555 engraved in small figures. It is requested that
the objective may be retained should it be offered for sale.”]

Central.-Ztg. f. Optik «. Mechanik, X. (1889) p. 148.

Hervurcs, H. van—La nouvelle combinaison optique de Zeiss et les perles de
VAmphipleura. (The new optical combimation of Zeiss, and the beads of
Amphipleura.) Bull. Soc. Belg, Micr., XV. (1889) pp. 69-71.

(5) Microscopicat Optics and Manipulation.

Diffraction Theory.—Prof. B. T. Lowne and Mr. E. M. Nelson
have been in controversy on this subject, the former attempting to ex-
plain the phenomena of microscopic vision on a dioptric basis, while
the latter supports Prof. Abbe’s views.

Prof. Lowne explains as follows} the advantages arising from the
use of lenses with a large numerical aperture, and of immersion lenses
respectively.

“The images seen with the Microseope are either brighter or
darker than the illuminated field. An opaque object appears black, when
illuminated from below it gives a negative image. <A transparent object
seen by transmitted light is less bright than the field, i. e. gives a negative
image, whenever it absorbs much light, and whenever it has a lower
refractive index than the medium in which it is mounted, except when it
acts as a concave lens; it is brighter than the field whenever it has a
higher refractive index than the medium in which it is mounted, except
when it acts as a concave lens, 1. e. it gives a positive image.

Diatoms have a lower refractive index than balsam, and seen by
transmitted light should give, in the majority of cases at least, a negative
image. Such a negative image is always complicated with diffraction
images, and is only seen with object-glasses having a low numerical
aperture. The dioptric image is necessarily feeble, as the diatom
permits much light to pass through it, and delineation is only possible
by means of diffraction images.

The case is, however, very different with high angles of aperture,
and especially with immersion lenses; the diatom image is then positive ;
it is brighter than the field. How can this arise? The diatom is self-
luminous, i. e. in the same sense as a piece of white paper is self-luminous.
Every point of the diatom radiates light, and every point is an inde-
pendent source of light, that is, the light radiates independently from
every point, the vibrations proceeding in every possible phase at every
instant, such light producing no visible interference phenomena,

The cause of the positive image is that the diatom is illuminated
from above, not from below, It is illuminated by reflected light from
the upper surface of the front lens of the objective.

It is well known that the pencil of light which falls upon a plate of
glass is partially reflected chiefly from the surface of emergence. This
surface of emergence of the front lens is a concave mirror, which con-
denses the reflected pencil upon the object. A very simple experiment

* Journ. de Microgr., xiii. (1889) pp. 481-2.
+ Journ. Quek., Mier. Club, iii. (1889) pp. 360-72 (4 figs.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 807

will convince the most sceptical of the great illuminating power of the
back of the front lens of an objective. Take a black-handled pocket-
knife, the smaller the better, with a bright stud upon it, hold it up
between the eye and a gas-burner, near the source of light; the stud is
invisible. Take an ordinary pocket-lens of an inch focal length or
thereabout, and without moving the knife, focus it upon the stud; it
will be brilliantly illuminated.

Any convex lens will give a brilliant inverted image of a flame upon
a small screen placed between it and the source of light, by reflection
from its back surface. Moreover, if we look at the lens the virtual erect
image of the flame seen on its back surface is nearly as bright as the
source of light, although, of course, much smaller.

With objectives of large numerical aperture, the working distance is
short, and with a large pencil much light is reflected upon the object.
With immersion lenses the reflection from the cover-glass and the front
of the objective is practically done away with, so that all the light
reflected from the upper face of the front lens falls upon the object.

Five per cent. of the light which falls normally on the back surface
of a glass lens is reflected, whilst the quantity which is reflected by
oblique incidence rapidly increases ; much light is totally reflected, the
whole converges after reflection once, twice, or thrice towards the object,
and it must be remembered that only the centre of the pencil falling
upon the back surface of the front lens is transmitted to the eye, whilst the
whole pencil is concerned in the illumination of the object from above.

I believe that this is the great advantage derived from high angles
of aperture, and more especially from immersion objectives.. The
elimination of the false diffraction images resulting from the large
illuminating pencil, and the reflection of light from the object, appear
to me to be the causes of the great increase of definition attained by their
use. The view propounded by Professor Abbe that they collect out-
lying diffraction pencils, appears to me quite inadequate to explain the
increase of definition.”

Mr. E. M. Nelson refutes Prof. Lowne’s suggestion by the following
considerations : *—“ One great objection to the dioptric theory is, that it
is unsupported by experiment. ‘I'he single experiment put forward may
be said to touch the subject only in an indirect manner. I allude to
the reflex from the objective front, to which I shall refer later.

(1) The point with regard to the images of the condenser diaphragm
at the back of the objective has nothing to do with the question.

Let us take a simple case—viz. an oil 1/8 of large angle focused
on a’P. angulatum, illuminated by edge of flame, centered and focused by
stopped-down condenser on object in usual manner. Now, if we examine
the back of the objective we shall see the usual picture of the diopiric
beam and the six spectra round it. The size of the dioptric beam—i.e.
the dise of light at the back-lens of the objective—will depend on the
size of diaphragm and angle of condenser. 'The size of the spectra will
equal the size of the dioptric beam. If the object be now taken away,
we shall lose the spectra, but not the dioptric beam. Now, no one
imagines for a moment that this image of the diaphragm is projected to
a focus at the objective conjugate ; what is projected there is an erect
image of the edge of the flame. If the object be replaced, there will be

* Eng. Mech., xlix. (1889) pp. 425-6 (4 figs.),

808 SUMMARY OF CURRENT RESEARCHES RELATING TO

an inverted image of it, in the erect image of the flame, independently
of any spectra.

Now with regard to the spectra. I well remember that the first
experiment I performed when the diffraction theory was new was to
receive the images on a piece of oiled tissue-paper at the objective back.
If my memory serves me right, you can trace an image of P. angulatwm
about half an inch from the objective back. The images will necessarily
be much out of focus, but, nevertheless, they can be made out. ‘There
were black outlines on a light ground in the dioptric beam, and a green
image in each of the six spectra. Remove the greased paper screen
further back from the back lens, and the six spectral images were seen
to coalesce with the central dioptric image. The point to be learned
from an examination of the back of the objective is the size of the cone,
or cones, which form the image at the objective conjugate.

Thus, the dioptric image of a point in the object is formed by a
cone, the base being the bright disc at the objective back. A spectral
image is formed by a cone, the spectral dise being its base, and so on.
I am of opinion that Prof. Abbe has established experimentally and
theoretically that the delineation of this microscopic image of the fine
structure of P. angulatum depends on the fusion of these green spectral
images with the dioptric beam and with one another.

(2) The next point is the extinction of the spectra by the dioptric
beam, or, more correctly, the effect of the spectra is so feeble in com-
parison to that of the dioptric beam, that their power to influence the
image is practically nil.

The answer to this is, that just as much as you increase the diameter
of the dioptric beam, so do you increase that of the spectra—a fact which
may be experimentally verified in two minutes. Thus, expand the
illuminating cone until it nearly touches the expanded spectra, now
stop out the dioptric beam, and look at the brightness of the spectral
image. Then, without moving the stop, reduce the illuminating cone,
and watch the diminution in the brightness of the spectral image.

Of course, it is impossible to carry on the experiment when the
dioptric beam overlaps the spectra, as it is impossible to cut out the
dioptric beam without cutting out the spectra as well. But it is for the
‘« dioptricians” to show why the brightness of the spectral image should
cease to increase at the point when the dioptric beam overlaps the spectra.
The brightness of the spectral image most certainly increases as you
increase the dioptric beam as far as you can carry on the experiment,
and I can see no possible reason why it should not go on increasing
until you reach your maximum cone.*

(3) The following experiment, although not proving, the matter,
points very strongly in favour of the diffraction and against the dioptric
theory. Examine a P. angulatum with a lens which, when illuminated
by a narrow pencil, will not grasp the six first-order spectra, and enlarge
the cone until the dioptric beam occupies, say, 3/4 of the back. Now,
if a lens of suitable angle has been chosen, the expanded spectra will just
cut into the peripheral zone of the objective. If the eye-picce is replaced,
delineation will be seen; but if a stop be placed over that peripheral
zone, although the large dioptric beam remains the same, the delineation
will have vanished. Ifthe image is a dioptric one, why, in the presence

_* Unless the experiment has been tried, one would hardly believe the great
brilliance of the epectral image when the dioptric beam has been stopped out.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 809

of such a large dioptric beam, are those little edges of spectra in the
peripheral zone so supremely important ?

(4) You cannot have an irregular picture from a spectral image. A
short time ago I also held this view, and I used to assign the irregu-
larities in the microscopic image to a function of the dioptric beam; but
special experiments, made with a view to determine this point, have
altered my opinion. Ina purely spectral image I have seen irregularities
in the microscopic image, such as a missing dot, &c. These differences
are not clearly seen, and yet they are seen. I do not for one moment say
that the dioptric beam has no influence on the image—it has a very great
influence ; in fact, a greater influence than perhaps any spectrum taken
by itself; but that is quite another matter altogether to saying that the
microscopic image is a purely dioptric one.

(5) The reflex from the front_lens. This is the only part of the
dioptric theory which has been supported by experiment. It is very well

Fie. 104. Fic. 105. Fic. 106.
CFS
O O

Sa
2 O S Fic. 107.

8 Ae ®,

EXPLANATION OF Fics.

Fig. 104.—Shows back of objective, with spectra of first order of P. angulatum,
the dioptric beam of small angle being stopped out. The diatom will be resolved on
a dark ground, and will be fairly bright.

Fig. 105.--The sume, with a dioptric beam of larger angle. The diatom will be
resolved and intensely lighted on a dark ground.

Fig. 106.—The same, with a smaller aperture, so as to admit only the edges of
the expanded spectra. The dioptric beam is now present, and the diatom is resolved

on a light ground.
Fig. 107.—The same, aperture of lens reduced, so as to cut out the edges of the
spectra; dioptric beam same as in fig. 106. The diatom is not resolved.

known that an object, such as a diatom, illuminated by a central axial
cone, appears brighter than the field.

The “ dioptricians” explain this fact by saying it is caused by light
reflected from the front lens of the objective, and this statement is sup-
ported by the experimental examinations of opaque objects mounted in
balsam.

I have very grave doubts as to the opacity of some of these objects
which shine so brilliantly; therefore, let us pass on to one object upon
which there can be no doubt—viz. the mercury globule.

On examination, a mercury globule exhibits a feeble illumination from
the reflected light. A great deal depends, however, on the curvature of
the front lens, which, of course, differs in lenses of different construc-
tions. It was found on trial that a certain dry.1/4 gave brighter
illumination than another dry 1/4, also both 1/4’s gave more brilliant
results than a certain oil-immersion 1/8. It was also found that the

810 SUMMARY OF CURRENT RESEARCHES RELATING TO

effect was heightened by racking up the condenser much within its
focus.

It is not difficult to calculate to what focus light, radiating from the
principal focus of the lens, will be brought by reflection from its
posterior surface.

Let us examine a particular case, say a hemispherical lens of 1/10 in.
radius, of crown glass, ref. index 1:5. Then by ordinary formula—

1 pilpy aes: b
Ft Cis) (ares
Wily oe

Now we have to find the apparent curvature of the concave surface as
seen through the plane. ;

ae
Rogoy

By formula—

where R is radius of curvature, F principal focus, and f the apparent
radius of reflecting surface seen through the plane—

1/10 = ues
f=1/15.

The next point we have to determine is the focus of a concave mirror
of 1/15 radius for rays coming from a radiant 1/5 in. in front of it. By
formula for a concave mirror—

1 dag

ae dea

dn ole Se
joer hy faa 0) 1175)
p = 1725.

Therefore we see the reason why the illumination by reflection from
the posterior surface of the lens should be feeble ; because it is brought
to a focus within the lens, and by the time the rays come to the object —
they are greatly dispersed.

When the condenser is racked up, the radiant is placed nearer the
concave surface, and its conjugate focus brought nearer to the object, and
consequently the illumination of it is strengthened. Therefore we can
see that the single experiment put forward in support of the dioptric

theory fails.
6th and last point. It is an established fact that the most critical of
all images are those on a dark ground. Here an objective is put on its
mettle, and its resolving power strained to the utmost, It is a great
pity that certain technical difficulties come in the way of this kind
of illumination with wide-angled lenses. Here we have no dioptric
beam, nothing but spectra, and we get a “true” image—i.e. one that

* Formula by C. V. Boys, F.R.S., in ‘‘ Measurement of Curvature and Refractive
Index,” ‘ Philosophical Magazine, July 1882.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. S11

behaves like a daisy under a 4-in. on focal alteration. Such a case is
quite inexplicable by a dioptric theory; but is quite consistent with
the views put forward in my last paper. When the back of the objective
is examined, it will be seen entirely covered with spectra, so no
zonal differences can exist, and consequently focal alterations will not
produce different images. The above seem to me to be the chief
objections to the dioptric theory.

In conclusion, let me say that the author of the dioptric theory has
done excellent work, although according to my own view he has failed to
establish his case. First, he has given the most concise and lucid
explanation of the interference phenomena that is extant in our
language. Secondly, he has given testimony to the fickleness of images
derived from a small cone of illumination.”

Mr. L. Wright * also writes on the same subject :—“I have myself
very grave doubts if this new theory is correct; but it is a singularly
interesting one. I draw attention to it partly as a proof that speculation
is not yet at an end, but chiefly to point out that there is one most
simple experiment, easily made, which will determine it with absolute
certainty. That is, to silver the back of the front lens, and then remove
the silver from the centre of the back only. The reflection from the
margin will be, if anything, rather increased ; and whatever becomes of
the theory in question, I believe the expedient may prove of some service
as an illuminator of certain objects, and may give valuable resolution of
structure by the modification in this point. But the silver will really
stop off all but the central pencil, which it will allow to pass unaltered ;
and if Prof. Lowne’s theory is correct, the ‘high’ resolution will be
unaffected. I hope such an experiment will be made without delay, and
it will be well worth while merely as one in illumination, if no one has
attempted it before. I am afraid, however, it will demolish the theory,
for if the latter be sound, one would say that all lenses with hemi-
spherical fronts ought to give equal resolution, irrespective of aperture,
which belongs to the back portion of the lens. This is not the case, and
I fear we have yet to find a theory which shall reconcile the undoubted
facts with conclusions that seem forced upon us by the phenomena of
physical optics.”

In reference to Mr. Wright’s suggestion, Mr. Nelson t points out a
way in which the experiment may be performed without silvering the
front lens of an objective.

An inch objective with a Lieberkiihn ought to resolve more than the
same lens without a Lieberkiihn with transmitted light, supposing the
hypothesis to be correct. If the increase of aperture is only useful for
illuminating the object by reflected light, and no rays pass through the
increased portion to the eye, it is abundantly evident that those conditions
are fulfilled by a Lieberkiihn. The experiment can therefore be easily
tried.

Prof. Lowne remarks { on Mr. Wright’s paper as follows:—*“I fear
the theory which I have suggested to account for the efficacy of large
apertures in microscopy cannot be so easily verified or disposed of as
Mr. Lewis Wright supposes. Before giving my reasons, I must correct
the impression which may evidently be made by an expression of mine,
and which it was far from my intention to convey.

* Enel, Mech., xlix. (1889) p. 391. ‘Te Le Ce pats f Te. pp: 487-8:

812 SUMMARY OF CURRENT RESEARCHES RELATING TO

In using the words quoted by Mr. Lewis Wright, ‘Only the centre
of the pencil falling on the back surface of the lens reaches the eye,’ I
was speaking of the intensity of the light illuminating each portion of
the object, and all I meant was that the effective emergent pencil which
enters the pupil is small as compared with the angular aperture of the
object-glass.

I admit that the eguetes is ambiguous, and should have been more
clearly worded ; but I never intended to convey the idea that the back
face might be silvered, leaving only a small aperture.

The idea of silvering the lens, as Mr. Lewis Wright suggests, did
cross my mind when I was working at the subject, but I saw at once
that it could not be used as a means of settling the question, and for
this reason. The object-glass is made experimentally, and the outer
zone is of the utmost importance, as it is far more easily corrected to
give’a sharp image than any other part of the lens.

It will be readily seen that if the lens surface be divided into a
number of concentric zonular elements, the more nearly these approach
the centre of the lens, the less the angle their normals make with direct
incident light.

If the aperture were small enough the lens would have practically
plane surfaces, and could not give any distinct. image other than that
given by a pinhole. The outer zones are so corrected that the pencils
passing through them come to the same foci as the central pencils—that
is, their chromatic and spherical aberration is reduced to a minimum,
whilst the intermediate zones are left uncorrected. If by any diaphragm
or other appliance the outer zone is rendered ineffective, the next outer-
most zone must be corrected.

I do not know whether it would be possible to reduce the apertures
of an objective, and re-correct the glass without increasing its working
distance. If this were possible, the glass might regain the definition
lost by the reduction of aperture, provided this reduction were not
great; but the experiment would be one of great practical difficulty, and
could only be carried out by one of the best makers of lenses, and then
only with great expenditure of time. I fear we shall have to be satisfied
with some less direct method of settling the question.

In my own mind there is no doubt whatever that all definition
would be destroyed by silvering the back face and reducing the aperture,
which is practically the same thing as putting a diaphragm behind the
objective, whether the image is a purely dioptric or a diffraction
phenomenon, unless some compensatory change could be made in the
glasses without altering the curve of the front lens or its working
distance.

I would remind microscopists that what I have said applies only
to critical images with high powers, and I would ask them to compare
such images with those seen by dark-ground illumination and lower
powers. The resemblance between the images produced by the two
methods of illumination is very striking.”

Prof. Abbe himself has also sent a paper to the Society (now in
process of translation) refuting Prof. Lowne’s suggestions.

Ultimate Structure of the Pleurosigma Valve.—At the October
meeting Mr. T. F. Smith read the following paper :—
Twelve months ago I had the honour of bringing before you some

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 813

researches on the valve of Pleurosigma, and claimed to have discovered
that what up to that time had been considered a single plate of silex
was really built up of two or three layers of structure. I also claimed
to be the first to call attention to this fact, but this claim I must now
withdraw, for the simple reason that I find on page 680 of the Journal
of this Society for 1879 the following passage from a paper by Herr
Grunow—with additional notes by Mr. Kitton—on the Diatomacee of
the Caspian Sea :-—

Speaking of Pleurosigma attenuatum and P. hippocampus, Herr Grunow
says :—‘‘ The structure of these allied forms under high powers appears
very similar; between the strongly marked lines of beads faint outlines
of other beads may be seen, Whether these delicate puncta belong to
a second valve or are an optical delusion must remain for the present
undecided; it is certain, however, that the valves of Pleurosigma are
composed of two layers, which separate when acted upon by long boiling
in acids.” And then between brackets, I suppose by Mr. Kitton, “I have
seen this in P. angulatum.” Then follows this note by Mr. Kitton :—
“The faint markings here alluded to have been seen by other observers.
It is most probable that the valves of Pleurosigma have a similar struc-
ture to many other diatoms in possessing what I call secondary valves,
which in some genera are like, and in others unlike the primary valve.”

The above passages show how remote the chances are of any single
individual being the sole discoverer of any new fact, whether important
or trivial; and although the only positive evidence given here is the
separation of the layers by boiling in acids, it is enough to bar my claim
to be the first to call attention to the compound structure. I think,
however, I may still claim to be the first to figure the structure of the
different layers, and am pleased to feel that my attempts in this direction
will derive additional weight from being corroborated by the testimony
of two such eminent observers as Herr Grunow and Mr. Kitton.

It is almost necessary to apologize for bringing this subject before
you to-night, as for some reason the study of diatoms in the present
day is almost a discredited one, and the microscopist who indulges in it
is looked upon as nothing better than a trifler in science. But I think
this stigma is an unjust one if we look at the important part the
resolution of diatoms has played in the development of the modern
objective, and thus placed in the hands of microscopists generally an
efficient instrument of research, without which many pages of Nature
must have remained a sealed book. The study of diatoms has also its
value—and with many its chief value—in their being one link in the
great chain of existence ; but it is purely from a brass-and-glass point of
view I wish to approach them to-night, and using them as a standard
of value, try to prove by the results of my investigations on the Pleuro-
sigma valve, how much further it is possible, by the use of the new
optical glass and proper methods of illumination, to push our researches
into the nature of all minute structures.

Practically, the resolving power of our objectives on lined objects
had reached its maximum before the advent of the new glass. The
Amphipleura pellucida marks now, as it marked then, the finest known
regular structure of any regular object. There was nothing further,
then, to be gained in resolution, but possession of one of the new
apochromatics, with its entire absence of colour, soon convinced me that
it possessed a power of separating different layers of structure altogether

$14 SUMMARY OF CURRENT RESEARCHES RELATING TO

outside the grasp of the ordinary achromatics. The result of this
increased power in my hands was to enable me to split up the supposed
one plate of silex forming the valve of P. formosum into three, and thus
add two more vertical notches to the standard by which we measure
our objectives.

The advantage of applying such increased power to the elucidation
of minute structure generally is so evident, that it is only necessary for
me to place the existence of the compound structure and its character
beyond a doubt to leave the matter in your hands to apply for yourselves.

When I had the honour of bringing this question before you twelve
months ago, I was met by the objection that the appearances I described
were diffraction effects—meaning false effects—and was asked if I had
examined the diatoms mounted in a dense medium as well as when
mounted dry. After the exhaustive manner in which diffraction has
been discussed within the last twelve months, and the modification of
opinion to which that discussion points, I do not think it necessary to
meet the first objection ; but on the second point I may say that I have
since examined a slide of Plewrosigma formosum mounted in phosphorus,
and found all my previous opinions confirmed. There has also cropped
up from time to time the objection that the interference of light coming
through a grating, and the impossibility of separating two such gratings
—if they existed—from each other must vitiate any conclusions that
might be drawn from mere visual appearances. I recognize the force
of the last objection, but at the same time beg to point out that within
certain limits it applies rather to the old dry objectives of narrow aper-
ture than to the new oil-immersions. With the latter the depth of
penetration is so little that if two layers are separated by ever so narrow
an interval, for all chance of interference they might as well be a mile
apart. Of course, in asserting this I am supposing a large central cone
of light, as being the only correct method of illumination with such a
glass, the slightest deviation from which will produce error. But even with
an oil-immersion of wide aperture it is still possible for two layers to be so
closely connected that interference occurs, and no doubt, under such cir-
cumstances, it would be impossible to be sure of the structure. Had no other
method been adopted by me than to record an appearance as true simply
because it appeared such under the Microscope, I should deserve all the
censure you could apply to such a method of working. Such, however, has
not been my method, but when there has been the slightest doubt, I
have formed no definite opinion of any structure until seeing it isolated
from everything which could interfere with the definition. Thus three
layers of structure have been figured by me in Plewrosigma formosum,
because I have been enabled to isolate them, but I have never ventured
upon describing more than two in the other species of this genus,
although one might be led by analogy to suppose there were three.
Leaving out the question, then, of the middle layer in. the finer forms as
one on which I can offer no direct evidence, the task is much simplified
when trying to prove the existence of two layers in Pleuwrosigma an-
gulatum, it being necessary only to deal with the two opposite sides of
the valve. On looking over a spread slide of this diatom, mounted dry,
we at once discover that different valves present different optical ap-
pearances, and on further examination shall also find that the different
valves have different curves, and that the same curves and appearance
always belong to each other. The prints here to-night marked 1 and 2

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 815

will illustrate this. Both are taken across the nodule, and while No. 1
starts straight from the median line and slopes down towards each edge,
No. 2 starts straight from the edge and slopes down towards the median
line. Now, if these two curves are placed opposite each other, there
will be a considerable space between them, and we are driven to this
conclusion, that either each side represents a different layer of structure,
or we have one very thick plate of silex—a supposition quite at variance
with what we know of diatom structure generally.

I have said that the same appearance is always identical with the
same curve of the valye—No. 1 showing white, and No. 2 black inter-
spaces ; but this only on condition that the largest cone of light possible
is poured into the objective. With a narrow cone of illumination the
two sides present the same image, but by using the largest aperture of
the achromatic condenser, and. placing the bull’s-eye condenser between
it and the mirror, the valves become at once differentiated in a manner
unmistakable.

I may state here incidentally that it is not possible to develope the
structure such a glass is capable of showing ; with only the edge of the
flame and dry achromatic condenser the bull’s-eye added between is
necessary, and with this the use and expense of an oil-immersion con-
denser is quite unnecessary. Of course I am aware that the aperture is
measured by the back lens of the objective. I know that the back lens
of an oil-immersion of 1:4 N.A. can only be filled with the use of an
oil-immersion condenser on an object mounted in the same refractive
index ; but I also know that the objective has not yet been made which
will allow the back lens to be so filled with light without utterly
breaking up the image. The full aperture of sucha lens, then, can never
be utilized, and the use of the bull’s-eye condenser will allow as much of
it to be used as is practicable.

IT am aware that my prints of Pleurosigma angulatum do not agree
with the celebrated print by Dr. R. Zeiss, exhibited here at the meeting
held on April 11th of last year, and which received the highest praise
at that time from some of our leading microscopists as being the greatest
advance yet made in the delineation of that diatom. I admit it to be a
very striking picture, that photographically it is deserving of all praise ;
but the conditions of its production are in violation of every principle
laid down by Dr. Abbe himself in his different papers on the theory of
microscopic vision. First it isa most flagrant example of what Dr. Abbe
calls empty magnifying power; and secondly, the image is false, for the
reason mentioned in his paper on the Relation of Aperture to Power,
wherein he shows that where the magnifying power of an objective is
pushed up much beyond the number of diameters necessary to show the
details resolved by the aperture, all details under such circumstances,
whether square, triangular, or lozenge shape, acquire the same appear-
ance of being round or oval. What then has happened in this particular
instance? The aperture of the objective by which the photograph of
Dr. Zeiss was produced has been narrowed down by insufficient illumi-
nation from 1:3 N.A. to 0°70; the power has been forced up to 4900
diameters, and the result is circles where there should be squares or
hexagons. 4900 diameters is more than 40 times the initial power of
the objective used, even if all the aperture had been utilized ; what then
can be the value of such an image as a truthful interpretation of
structure when produced with little more than half that aperture? In

816 SUMMARY OF CURRENT RESEARCHES RELATING TO

taking up this position with regard to the relative truth of the respective
prints, I am asserting nothing but what is within my own knowledge;
both Mr. Nelson and myself having produced exactly the same photo-
graphic image as Dr. Zeiss with the dry apochromatic 1/4 in.

But to recur to the proofs of the compound structure of the Pleuro-
sigma valve. It is not necessary that I should weary you by giving in
detail all the evidence I have collected, but will call your attention to
two prints only of a valve of one of the Pleurosigma I have taken at two
different planes. In both prints a bit of the valve is shown chipped
away, but while in the print taken at the lower level, the hole is clean
through, in the upper a fine grating is seen projecting over the hole,
and nothing, I think, can be more conclusive of different layers. Having
done my best to establish the existence of different layers in the
Pleurosigma valve beyond a doubt it now remains to determine, if
possible, the ultimate structure of each layer in one species, and then to
establish the nature of the ultimate structure as between one species
and another in the same genus. When a number of forms agree in
shape and their leading features, and the only difference between them
is the relative coarseness or the fineness of their structure, you cannot
draw a line and say, “Here ends truth and here begins error.” It must
be true throughout or false throughout, and to establish the truth of the
one will establish the truth of the other. Let us see then; first, what
are the leading features common to all the Pleurosigma, and secondly,
how far we can make sure of the ultimate structure of the coarsest form,
that is of Pleurosigma formosum. It is not necessary to say anything
about the common shape which gives name to the genus, or the median
line, to an assembly like this, but I may mention one peculiarity of the
nodule common to all the species having the diagonal markings which

I do not think has been mentioned before. On one side

Frc. 108. of the valve there is simply a cavity at that point, but on

the other side the median line at the nodule is joined as in

—_ > fig.108. My attention was first called to this by examining

a type-slide of the Plewrosigma, where I found it in form

after form. Another feature common to the same forms,

is two rows of perforations larger than the others running lengthways

on the valve, one on each side of the median line and two similar

rows, one on each outer margin. Lastly, in all the species having

diagonal markings there is the common feature of the structure being

composed of a square grating with a focal image formed in each

alternate square. This is enough, I think, to show that whatever the

structure may be it is of the same character throughout, and it now

remains by examples to find out if possible, what is the unit of that
structure.

Whatever difference of opinion there may be about the truth of the
image of a structure when it recurs at regular intervals, there can be
none when you get an isolated particle or fibril, which, existing already
as a unit, cannot be the double or the quadruple of another unit. Such
a unit I have found of the structure of Pleurosigma formosum floated
entirely away from the valve. It seems to consist simply of a series of
short bars of silex placed lengthways on the valve, side by side, in such
a manner as to leave alternate interspaces between them (see fig. 109).
It will be seen from a study of this diagram how the ordinary appearance
of the Pleurosigma is produced. The larger interspaces, being produced

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 817

alternately, are seen running diagonally across the valve, and an image
of the larger interspaces, thrown there from the under layer as on a
screen, gives rise to the appearances which have produced so much con-
troversy as to whether the ‘‘markings”” are beads or perforations. As
a matter of fact they are neither,

but simply a collection of focal Fic. 109.

images or ghosts, and you may
as well speak of the picture
thrown by the optical lantern on
a screen as the structure of that Fees A | fe = Se oe
screen, as speak of these focal

images as the structure of the Ag
diatom. I have a valve of Pleuro-
sigma formosum under the Microscope here to-night which shows finely
the arrangement of the fibrils on the valve. In some parts of the valve
the fibrils are seen lying loose, in other parts close together, form-
ing regular structure, while in other parts they are wanting altogether.
A print of the same valve shows in parts a regular collection of white
“beads,” which are ghosts and utterly wanting where the outer membrane
is torn away. The distance apart of the alternate squares from the
centre of each other on Pleurosigma formosum is double that of Pleuro-
sigma angulatum, and our difficulty is enormously increased when we try
to determine the structure of the latter. To me it is sufficient that the
two images present the same characteristics to convince me that the
structure is the same, but I know that other observers want more positive
evidence, which for a long time I was unable to give. What was wanting
was corresponding torn structure, and at last I am able to put that in
evidence also—not, I confess, in Pleurosigma angulatum proper, but in
an allied species, which for our purpose is practically the same. Thé
strie are of the same fineness—50,000 to the inch; there is the same
arrangement of large perforations on each side of the median line and
the margins; and the finer structure shows the same focal images formed
in alternate squares. On one corner of the valve of which I show a
print, the outer layer is stripped off, leaving the under one intact—found
on focusing down—while on the lower corner the fibrils are lying in
strips, and are of exactly the same character as those we have seen in
Pleurosigma formosum.

Disturbances of Vision consequent on Microscopic Observation.*—
M. C.J. A. Leroy has noted a peculiar disturbance of vision which
affects exclusively the eye which has not been employed during micro-
scopic observation. Letters seen at the usual testing distance of 5 m.
were blurred, and this effect was not corrected by spherical glasses or by
efforts of accommodation. In the table of radiating lines used as
diagnostic for astigmatism, the horizontal lines were disturbed while
the vertical ones remained clear, and no cylindrical glasses modified
the difference: thus the disturbance was not due to defect in accom-
modation or to simple astigmatism. The author was led to the con-
clusion that it is a diplopia always produced in a vertical direction
by noticing the fact that the horizontal lines of the curtain traversing
the top of the machine gallery in the Paris Exhibition was distinctly
double. This diplopia has its origin in the dioptric apparatus (cornea or

* Comptes Rendus, cviii. (1889) pp. 1271-3.
1889. 3 i

818 SUMMARY OF CURRENT RESEARCHES RELATING TO

crystalline) of the eye and not in the cerebro-retinal centres, for on ex-
amining a horizontal line through a small hole from 0°8 mm. to 1 mm.
one of the images only was seen, but both became successively visible on
displacing vertically the hole, and on impressing a suitable velocity on
this displacement an undulatory appearance was given to the line. No
phenomena of double refraction were observed on examining with a
nicol. In certain instances triplopia was also obtained, the third image,
however, being very pale. The energy and duration of the disturbance
was naturally found to vary with the length of microscopic observation,
and its disappearance was progressive and continuous. ‘Thus, on one
occasion, when the author began work (observation of diatoms) at 10
in the morning, at 10.30 there was diplopia, and at 11 triplopia. The
separation of the images was then measured and amounted to 4' for the
second and 8! for the third. At noon the triplopia had disappeared,
but diplopia still remained.

Apart from microscopic observation diplopia was also found to
result from observing across a small hole a phenomenon difficult to catch
at the moment of its appearance or disappearance in a very limited field,
and also in some degree from examining ophthalmometric images.

M. J. J. Landerer,* in reference to M. Leroy’s note, claims to have
been the first to call attention to this phenomenon, and adds the fol-
lowing remarks concerning it :—

(1) Although the effort experienced by the eye seems to be of the
same nature for microscopic as for telescopic vision, yet the disturbance
consequent in the closed eye is much more marked in the first case
than in the second. This difference is maintained not only when the
telescopic object is so difficult a one to catch with a telescope of 108 mm.
aperture as the shadow of the second satellite of Jupiter as it is pro-
jected on the edge of the planet, but also when the image has considerable
brightness, as when the granulation of the sun’s surface or the spots are
examined through only a slightly blackened glass. This difference is
not due to the different inclination of the head in each case, for it still
persists when the telescopic observation is made by means of the bent
eye-piece.

(2) That during microscopic observation there is a crossing of the
optic axes of the two eyes, producing an effect similar to that of strabism,
is proved by the fact that by giving them this disposition, and then
applying the eye to the eye-piece, the image is seen with perfect dis-
tinctness.

It is the simultaneous effort of both eyes which explains the dis-
turbance undergone by the closed eye. But as this effort acts in an
unconscious way, and has struck no one’s attention, it has been supposed
that there is here only an effect of accommodation producing the defi-
nition of the image at the distance of the punctum proaimum. The
above facts appear really to show that this is not the case, or, at least,
that there is no reason to affirm that the image is not defined at the
distance of distinct vision properly so called.

Amplifying Power of the Microscope.}---Dr. L. Didelot has applied
to the Microscope the notions and formule concerning the amplifying

* Comptes Rendus, cix. (1889) pp. 74-5.

+ Didelot, L., ‘Du Pouvoir amplifiant du Microscope: détermination théorique

et experimentile suivie d’une table a quatre décimales des inverses des 1000 premiers
nombres de 0°01 a 10°00,’ 2nd ed., 8vo, Paris, 1887, 86 pp. (1 pl.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 819

power of optical instruments as given in the latest discussions on the
subject, and gives an experimental determination of the dioptric, and
thence the amplifying power of the Microscope by the methods used in
the Laboratory of Medical Physics of the Faculty of Lyon. At the end
of his paper he gives a table of the inverses of 1000 numbers from
0°01 to 10°00, by which dioptrical calculations are much simplified.

The conditions of visibility of an object seen by the naked eye and
under constant illumination depend on the linear dimensions of the
object, its distance from the eye, and on the acuteness of vision. If y
is the absolute length of the object, and J its distance from the eye, the
y
T°
inverse ratio to the minimum visual angle under which two separated
luminous impressions are distinguished, so that if v denote the degree
of visibility of an object seen by an eye of acuteness V, we have

visual angle is proportional to The acuteness of vision is in the

— vi :
For an eye assisted by any optical apparatus, the four magnitudes
v, V, 1, y will take new values v', V',/' y', y' denoting the image of y. The
ratio of visibility of image and object W is then given by the equation

a> ON gt
Wari kei Tick @)
which may be written
ai! Ge
Cre @)

by replacing the ratio of the trigonometrical tangents and 5 by the
angles a’ a under which image and object are seen, or by the ares which
they intercept on the retina. For the same eye V = V' and the ratio of
visibility becomes the amplifying power I’, which M. Monoyer defines
as “the ratio in which an instrument increases the apparent magnitude
of objects,” and we have

a

i
a.

The object of a magnifying instrument is to increase the visibility
of objects. Formula (1) shows that this can be attained either by
diminishing J’, as in the simple magnifier, or in augmenting y' as in the
projection-lens or solar Microscope, or, finally, in uniting both, as in
the compound Microscope. The degree of visibility, then, does not
depend solely on the magnification (grossissement), i.e. on the ratio of the
absolute dimensions of image and object, but also on the distances from
the eye; and it is to a confusion between magnification and amplifying
power (pouvoir amplifiant) that many erroneous results are to be attri-

buted. Thus, the formula given by many authors,G = 1 + a introduces

the distance of distinct vision D, but neglects the distance of the lens
D

from the eye. The older formula G = :. in use up to the beginning of

eerliere

820 SUMMARY OF CURRENT RESEARCHES RELATING TO

the century, is still more inaccurate. It is of little importance, in order
to distinguish the details of an object, that its aerial image should be
much magnified, since it is so much the further from the eye, and so its
apparent diameter is diminished. It is the image on the retina which
should be magnified, and the effect of a lens will be measured by com-
paring the retinal images of the same object seen successively through
the instrument and by the naked eye. By following up this principle,
which had been previously grasped by Verdet and Guebhard, M. Monoyer
has obtained a general formula applicable to all optical instruments.

Thus, taking the case of a simple lens represented by its principal
planes reduced to a single plane H K (fig. 110) at a distance d, from
the nodal points of the eye united at the point O, let PQ=y be an
object situated perpendicularly to the optical axis of the eye at a
distance from the lens less than its principal focal length FH =f. Join
P and its image P’ to O, and prolong these lines as far as the retina;
let a and a! be the angles which these rays make with the optic axis, and
let J and /' be the distances of object and image from O. Then if T
denote the amplifying power, G the magnification, and L' the inverse
of 7’

i.e. the amplifying power of an optical instrument is equal to the
product of the magnification by the ratio of the distances of the eye
from the object and its image. In the case of the simple lens M.
Monoyer distinguishes several kinds of amplifying power.

(a) Relative amplifying power, corresponding to 1 = 1, i.e. com-
parison of the retinal images when the object is situated at an invariable
distance of 1 metre from the eye.

We have then |
Lae (Ce Ibi (4)
But

G9 alt (5)

where F ate and q' is the distance of the image from the second
principal focus F’ and = 1’ + f — d).
.'. by substitution

r=U+f—da)F.U=F+U1'0 - dF). (6)

This expression is identical with that which gives the dioptric power
®,,, of a binary system composed of two diopters of powers F' and L’.

In the case of the compound Microscope the dioptric power and focal
length are of opposite sign. Denoting these by ® and ¢ respectively,
we have

r= (oe = loa) (7)

Formula (6) serves to show the influence of accommodation ; for take
the case of the lens close to the eye and d, < f; then the term 1 — d, F
is positive, and the amplifying power augments with L’. The accommo-

821

ZOOLOGY AND BOTANY, MICROSCOPY, ETC.

822 SUMMARY OF CURRENT RESEARCHES RELATING TO

dation, therefore, should be as large as possible, so that the image might
form as near as possible to the eye. If, on the other hand, d, >/f,
1 —d,F is negative, and to augment the amplifying power L' must
diminish, i.e. I’, the distance of accommodation, must be as large as
possible. The most advantageous case is that of a hyperpresbytic eye,
in which case L’ is negative. For the Microscope the conditions are
inverse.

(b) Comparative amplifying power corresponding to the case in
which /' = J, i.e. the image is compared with the object supposed to he
placed at the same distance from the eye.

In this case we have

ea

(c) Absolute amplifying power, which represents the proper action
of the instrument supposing the object placed at the same distance from
the eye assisted by the instrument as from the naked eye.

We have

l=d,+f— 4:
where q is the distance F Q,
2
= dy = 7. = - 2 (8)

Substituting in formula (8) we have
2
r= GLi(d, +f-5)

1 gd lead oa (9)

on replacing G and q' by their values q' F and l’ + f — d, respectively.
Where the principal space « cannot be neglected,

L=d,+f—Q+s5

and the formula becomes
T,=1+d,FQ —4d,L’)+eT,.

When either the relative or absolute amplifying power is known, the
other can be determined by the connecting formula

P= Tax. (10)

For the simple lens, Microscope, or ophthalmoscope the consideration
of the relative is of more importance than that of the absolute amplifying
power; but for telescopes or spectacles, in the use of which we are not
free to modify the distance of the object from the eye, the absolute
amplifying power alone can be used.

For the case of the astronomical telescope, where the dioptric power
is zero, M. Monoyer * has given the formula

* Comptes Rendus, June 18th, 1883.

2

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 823

F, and F, denoting the dioptric power of objective and eye-piece, d, the
space between the first principal point of the objective and the second
principal point of the eye-piece, d, the distance of this latter point from
the first nodal point of the eye, l’ the distance of accommodation, and q
the distance of the object from the first focus of the objective.

More recently M. Monoyer has arrived at a formula more particularly
applicable to spectacles, viz.

1 —d,L
em ra (12)

A comparison of different formule for the magnification shows that
the majority of authors, such as Martin, Deschanel, Jamin, use formule
belonging to the form

in which I’ is the distance of distinct vision.

The magnification thus defined answers to the comparative amplifying
power, if we make / = /'.

The consideration of the formule proposed by Rees, Verdet, and
Guebhard shows that these authors, in order to appreciate the influence
of the lens on the visibility of an object, have had recourse either to the
magnification or to the relative amplifying power. M. Panum alone has
calculated the absolute power. The conclusion drawn by the author is
that M. Monoyer’s formula possesses a degree of generality and simplicity
which warrants its adoption in preference to all others.

In the experimental determination of the amplifying power of the
Microscope, use is made of the fact shown by formula (6) that under
two circumstances the amplifying power I becomes equal to the
dioptric power F, viz. when L’ = 0 or when d, = f. A determination
of the dioptric power for the latter case when the second focus coincides
with the first nodal point of the eye, consequently gives the amplifying

ower. ;
z Two methods for determining the dioptric power are given, dis-
tinguished as the method of precision and the rapid method.

The method of precision depends on the first formula of magnification

ear,

Two measurements of the magnification are taken with the object
placed successively at two different arbitrary distances. The cor-
responding magnifications are

G, = f
Nn
ehes
qr
whence
I 1.
a-a-F(g-q)
and

G, — G,
(q2 = q:) G, G,

§24 SUMMABY OF CURRENT RESEARCHES RELATING TO

q, and g, denoting the successive distances of the object from the first
focal point of the Microscupe, though only their difference, i.e. the
displacement of the object, need be known.

In the experimental determination the apparatus employed comprises
a Helmholtz ophthalmometer A B (fig. 111), and a diffraction bank AS
as constructed by Duboscq. On the bank directed parallel to the
horizontal optic axis of the ophthalmometer are three vertical supports,
carrying respectively the dioptric system L L', a micrometer P, and a
screen of ground glass beyond which is the source of light 8. To
apply the above formula a first magnification G, made by LL’ of the
micrometer P, is measured with the ophthalmometer. ‘The micrometer
is then placed at P,, and the second virtual image P,’ measured by the
ophthalmometer gives the second magnification G,. The displacement
P,P, = @ — q, is read off on the bank.

The rapid method for determining the dioptric power, which makes
use of the camera lucida to measure the magnification of a micrometer,
depends on the other expression for the magnification, viz.

G, = q,' ¥ = (i) +f—- dy) ¥.

Two processes can be employed.
(1) Keeping d, constant and displacing the object, its image is
formed at a new distance I,’ from the eye, and a second magnification is

given by
G, = q.P = (1, +f- dy) Ls

whence by subtraction

Gi Gi:
mea

In the experimental determination the image of the micrometer is
projected by means of the camera lucida on a plane containing a divided
scale, and the ratio of the lengths superposed gives the magnification.

(2) The second process consists in making d, = f, which reduces
the above formula to

Gal F,
whence

T Ps

so that only one determination of the magnification is necessary. The
apparatus employed consists of a horizontal scale (fig. 112) one metre in
length, a Wollaston camera P, and a micrometer M, illuminated by a
source of light S situated on the other side of a screen of ground glass EH.
‘The scale, clearly graduated in centimetres and half-centimetres from
0 to 50 starting from the middle, is strongly illuminated by two gas-
burners placed at each end. The camera lucida is placed at the same
height as the scaie on the perpendicular to its middle point, and at a
distance from that point a little less than 5 metres, so that the eye at N
may be accurately at that distance from the scale.

The reflecting face mn of the camera is inclined at an angle of 45°
to the axis N O, and one of the faces of the right angle only intercepts
half the cone of rays falling on the eye from the scale.

The micrometer M has for weak magnification a length of one centi-

i

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 825

metre divided into half-millimetres ; the four central divisions are sub-
divided into 10ths of a millimetre; it is engraved on horn. For strong
magnifications the micrometer engraved on glass has a length of
1 millimetre divided into 50ths or into 100ths of a millimetre.

In order to see, before making a determination, that the camera itself
gives rise to no magnification, at A’ B’ is placed a second scale 1 metre
in length, of which the middle point M’ is at the same distance from the
camera as the middle point O of the other scale. When M’ F’ is exactly
equal and perpendicular to N O, the eye placed at N sees whether the
virtual image of the scale seen by reflection in the camera is exactly
superposed over the first scale seen directly.

A camera lucida in which only one reflection occurs, is more suitable
than one in which two reflections take place, such as that of Oberhausser
and Nachet, since in the former the exact point N occupied by the
summit of the cone of reflected rays is known, whereas in the latter a
graphical construction would be necessary to determine it. The author
draws attention to the error which can follow from neglect of this point
and demonstrates how with cameras like those of Nachet and Oberhausser
two equal figures drawn in the same plane can never be exactly superposed
for an eye which receives them both at the outlet of the camera.

In making a determination, the dioptric apparatus to be examined is
placed in front of the camera with its optic axis F’ M’ at right angles to
the line of vision N O, and passing through the middle point M of the
micrometer. A preliminary observation by the aid of the sun’s rays gives
the position F’ of the second principal focus. The distance of the
diopter from the camera is then regulated so that the focus F shall,
after total reflection and deviation through 90°, coincide with the nodal
point N of the eye. For systems of very short focus, the eye is armed
with a spectacle-glass, as recommended by M. Monoyer.

The number of divisions are then read off on the scale which are
exactly covered by a given number of divisions of the micrometer. The
ratio of these two gives the magnification at 5 metres. In taking the
fifth we have in dioptrics the power of the system.

The preceding method is not applicable to the eye-piece on account of
the image being virtual. The difficulty is obviated in the following
way. Observation is taken of the magnification of the Microscope with
the eye-piece in place, which gives, say, dioptric power ®,. A second
observation is then taken with the eye-piece completely drawn out,
which gives a second dioptric power @,. The extent of the drawing out
of the eye-piece is measured. The formula for a system of two lenses of
dioptric power F, and F,, and at distances d, and d, apart, gives

&,—6,),2,= d,F,¥, — (F,+ F,)
®, = 6, F, F, = dF, F, — (F, + F.)
whence by subtraction

&, — 9%, = (3: —d;) F, F, = (d, = d;) F, F,
and
®, — ®, Pod ®,

Tae Gee = dB

For any system of lenses on the same axis can be substituted

826 SUMMARY OF CURRENT RESEARCHES RELATING TO

theoretically one single lens defined in position on the same axis by four
points, viz. the two focal points and the two principal points. If one of
these pairs of points has been determined, a knowledge of the dioptric
power gives the other pair.

Two methods are given for the experimental determination of the
focal points of a centered dioptric system.

(1) The first process depends on the formula of magnification

C= f

al

If p denote the distance of the object from the nearest face of the
diopter, p, the distance of the first focal point from the first face of the
diopter, we have

{=P — Pp;
Then
G = if )
P— Pr
and
et tf
Pr =P = Gi

Thus, in order to know p, it is necessary, during the determination
of the magnification, to measure the distance p of the object from the first
face of the diopter.

The determination of the second focal point is made in the same
manner by reversing the system.

(2) The second method depends on the formula,

Grae
in which q = p' — p';,
p' being the distance of the image from the nearest face.

The practical operation consists in the employment of a sufficiently
powerful Microscope. The image and refracting surface are brought
successively into focus for that Microscope; the displacement, measured
by a micrometer-screw, gives the absolute position p’ of the image, and
thus the second focal point is obtained. The first is found in the same
manner by reversing the apparatus.

The position of the focal points being known, that of the principal
points is obtained by measuring off the focal length from these points.
Finally, the principal space (distance between the principal points) is
obtained by measuring the thickness of the system i. e. the distance
between the summits of the extreme refracting surfaces. These pro-
cesses for determining the optical constants have the advantage over
those of M. Cornu, who uses the formula of conjugate foci, in that the
apparatus under examination can be kept in a constant position.

When great precision is not required, the following simple method
may be used :—An object strongly illuminated at the side of the observer
throws its rays on a small plane mirror at a distance of about 5 metres.
The beam reflected nearly normally traverses the Microscope under
experiment, and gives a very small image of the object, as if the latter
were disposed at a distance of 10 metres. The image is situated so near
to the principal focus that the difference is negligible.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 827

Finally, the focal points can be determined correct to some tenths of
a millimetre, by the aid of the sun’s rays without the use of a Microscope,
in the following way :—The diopter under examination is fixed with wax
to the slide of a slide-rule furnished with a vernier reading to tenths of
a millimetre, and the optic axis is brought parallel to the rule. A piece
of black paper is gummed on the rule at the zero of the graduation, and
the surface of the diopter is brought in contact with it; a first reading
is taken, and then, with optic axis turned towards the sun, the diopter is
separated from the paper until the observer, with the aid of a lens, sees
the refracted cone reduced to a brilliant point. A second reading is taken,
and the difference gives the distance of the focus from the first refracting
face.

Microscopes are usually provided with a set of eye-pieces and objec-
tives, which can be associated in different ways. To calculate in
advance the dioptric power of any associated system, we have the formula
for a binary system of diopters F,, F,

@= dF, F, — (F, + F;),

where d is the distance between the second principal point of the first
diopter and the first principal point of the second. If e¢,¢, and E denote
the thickness of objective, eye-piece, and whole Microscope respectively,
nthe distance of the second principal point of the objective to its last
face, and y, the distance of the first principal point of the eye-piece to
its first face

d=EH— (e+ 6) +m +

Just as the dioptric power of the eye-piece was obtained from those
of the objective and of the Microscope complete, so by an analogous
method can its cardinal points be obtained.

Thus supposing known

Ei, @1, €2-

™ m' the distances of the principal points of the objective to the
corresponding refracting surfaces.

® the dioptric power of the Microscope.

die ve ‘a objective.

F, ee a eye-piece.

p'» the distance of the second focal point of the Microscope to
the last refracting surface.

We have, to determine ,, d = E — (e,; + e) + m + 1»

but
®+F,+F, £4©
d=—y ep, tht

Therefore 7, is known, and by adding algebraically the focal length
fy the distance of the first focal point from the first face is obtained :

i= > (n: = fa):

To determine the second principal point, denoting by p' and q¢
the distances of the second focal point of the Microscope from the last
refracting surface and from the second focal point of the eye-piece

828 SUMMARY OF CURRENT RESEARCHES RELATING TO

respectively, and by p'y, the distance of the latter point from the nearest
refracting surface, we have

Po — Co = Pye
But the formula of conjugate foci gives
glide Sf?

LO dee =f,

Thus p'y, is known since pg is given by experiment, and so also
n'. Since
1's = So — P'fe
In the following table are given the results of applying the preceding
experimental methods and calculations to a Vérick Microscope with
objective No. 2 and eye-piece No. 1.

Experimental Data.

BE = 176™ Dh =e ol of. = om

Pret ESS) ®, = 250° Fires OTL

€, = 46™™9 ®, = 365° po = 1b" ab
dy = d, = (yaya 5)

where ©,, ©, denote the dioptric power of the whole Microscope with
eye-piece in place and drawn out through 62™-5 respectively, po the
distance of the first focal point of the whole Microscope from the first
face, and p'f; the distance of the second focal point of the objective from
its last face.

Caléulated Results.

ts = 197-5 Vo = AD LA = DIB ED S155
i = Agets/() Pf, = 165 16 = lips 2) Le}
F, = 23? y = 10™-87 pi, = lean
i ee ae i eo ng = — 427-246
d = 191™"°8 R= 6722: 33

where. q@ denotes the distance of the first focal point of the whole
Microscope to the first focal point of the objective, and pf, the distance
of the first focal point of the objective to its first face.

The author concludes by pointing out the advantages which would
result if constructors of Microscopes would take care to provide the
micrometer-screws with a graduation, and ‘would furnish with every
instrument the optical constants which alone determine its scientific
value.

The author arranges his conclusions under the following twelve
heads :—

I. The magnification of an optical instrument does not give the
measure of its useful effect.

II. The amplifying power is equal to the product of the magnification
by the ratio of the distances of the eye to the object and to its image.

TII. Two kinds of amplifying power may be distinguished: the
absolute and the relative. For the Microscope the latter is the more
important.

IV. The relative amplifying power is equal to the dioptric power

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 829

of a binary system formed by the association of the instrument with a
diopter equivalent to the state of accommodation of the eye.

V. Most authors have treated the influence of an instrument on the
visibility of objects by the consideration of magnification ; some by the
relative amplifying power; M. Panum alone has given an expression
equivalent to that of the absolute power. The formula of M. Monoyer
has the advantage of being more simple, of being applicable to all optical
instruments, and of taking account of all conditions of distance, of the
instrument, of the object, and of the accommodation.

VI. The relative amplifying power becomes equal to the dioptric
power only under two circumstances; when the distance of accommo-
dation is infinite, whatever the distance of the instrument from the eye,
or when the second focal point coincides with the first nodal point of
the eye, whatever the distance of accommodation.

VII. The dioptric power can then serve to measure the power of the
instrument.

VIII. The dioptric power of an instrument situated at an invariable
distance from the eye is obtained by dividing by the displacement given
to the object the difference of the two magnifications which result from it.

IX. The dioptric power of a system of which the second focus
coincides with the first nodal point of the eye is equal to the quotient of
the magnification by the distance of accommodation. Thence follows a
very simple method for experimentally determining the dioptric power.

X. The determination of the cardinal points of a centered dioptric
system, hitherto obtained by the application of the formula of conjugate
foci, is advantageously obtained by the aid of the formula of magni-
fication.

XI. This determination can be effected by the aid of simple apparatus
without making very important errors. It would be facilitated if instru-
ment-makers would furnish the micrometer-screw with a graduation.

XII. Every Microscope offered by a maker ought to be accompanied
by the optical constants most accurately ascertained, which alone deter-
mine the value of the instrument.

Royston-PraotTt, G. W.—Microscopical Imagery.
[Brilliant miniatures and minute molecules—Colias Cesonia.]
Journ. of Microscopy, Il. (1889) pp. 205-9 (1 pl.).

(6) Miscellaneous.

The late Chas. Fasoldt.*—The following obituary notice is from
the pen of Prof. W. A. Rogers.

“‘ Microscopists will hear of the death of Mr. Fasoldt with unfeigned
regret. The work which he has done in fine rulings and in micrometry
entitles him to a better recognition than he has received. While there
may be a difference of opinion in regard to his skill in the production of
test-plates, as compared with Nobert, it must, I think, be admitted that
he has made some plates which are quite as good as the best of Nobert’s.
When it is remembered that he must have been more than fifty years of
age before he took up the problem of micrometric rulings, and that he had
had no previous knowledge of the subject, his success has certainly been.
most remarkable.

Two circumstances have acted as a hindrance to the recognition to

* The Microscope, ix. (1889) pp. 174-5.

830 SUMMARY OF CURRENT RESEARCHES RELATING TO

which he is really entitled. Both of these circumstances have affected
his reputation abroad somewhat unfavourably.

The first is the very large claims in regard to his work put forth for
Mr. Fasoldt by some of his friends, and to a certain extent, it must be
admitted, by Mr. Fasoldt himself. The second is a rugged and some-
what unusual style in his public communications. The latter must be
charged wholly to the fact of his inability to convert into felicitous
English an essentially German style of speech.

Mr. Fasoldt was a mechanician of rare skill, and he had that element
of character which is almost always found associated with real genius—
supreme confidence in his own work. This striking trait of his character
was of real advantage to him, since it led him to answer criticism by
doing better work in new ways. The improvement in his micrometers
is especially noticeable. At one time he claimed that his micrometers
had no measurable errors. This was simply an expression of faith in
his own work at that time. With more experience he found that he had
been too sanguine, and so he set for himself the problem of finding the
best way to overcome these errors. It will be admitted by all who have
used his micrometers, especially those made within the last five years,
that his success in this direction has been remarkable. The fact that
Mr. Fasoldt, at one time, thought he had reached a degree of perfection
greater than is in reality possible, ought not to be remembered against
him. He is not the only person who has had, at different times, too
great a degree of confidence in his own work, as the writer can testify
from personal experience.

Mr. Fasoldt maintained great secrecy in regard to his methods of
ruling. The writer believes that the secret of his success consisted
wholly in his skill in the preparation of his ruling diamonds. There is
some evidence, derived from measurements of his rulings, that he did
not use a screw. According to my own experience, there is no difficulty
whatever in making the mechanical subdivisions of the ruled spaces far
beyond the ability of the ruling diamond to cut a clean line, which has
a width less than the interlinear space. But whatever method Mr. Fasoldt
may have employed, the results which he obtained must always command
the admiration of microscopists, and the service which he has rendered
in micrometry deserves grateful recognition.”

Scottish Microscopical Society.—We are glad to note that a Micro-
scopical Society has been founded at Edinburgh under this title with
every prospect of a successful career. The following gentlemen are the
office-bearers for the current year :—

President—Prof. Sir William Turner, M.B., F.R.S., LL.D.,Edinburgh.

Vice-Presidents—Prof. D. J. Hamilton, M.B., F.R.S.H., Aberdeen.
Adolf Schulze, F.R.S.H., F.R.M.S., Glasgow.

Secretaries—Alexander Edington, M.B., C.M., Edinburgh. George
Brook, F.R.S.H., Edinburgh.

Treasurer—-John M‘Fadyean, M.B., B.Sc., F.R.S.E., Leith.

Curator—German §. Woodhead, M.D., F.R.C.P.E., F.BRS.E.,
Edinburgh.

Council—Prof. T. Annandale, F.R.C.S.E., Edinburgh; Prof. I. B.
Balfour, M.D., F.R.S., Edinburgh; Prof. W. 8S. Greenfield, M.D.,
F.R.C.P., Edinburgh; Prof. J. B. Haycraft, M.D., D.Sc., Edinburgh ;
James Hunter, F.R.S.E., F.R.A.S., Edinburgh; Robert Kidston,

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 831

F.R.S.E., Stirling; Prof. W. C. M‘Intosh, M.D., F.R.S., St. Andrews ;
Robert Peel Ritchie, M.D., P.R.C.P.E., Edinburgh; Prof. William
Rutherford, M.D., F.R.S., Edinburgh.

The following list of papers at the second Ordinary Meeting on
15th November shows the nature of the work the Society propose to
undertake :—

1. On the histology of the Zoantharia, with demonstration, by George
Brook. 2. Demonstration of the histology of the Whale’s Stomach, by
G. Sims Woodhead, M.D., and R. W. Gray. 3. On the use of Blood-
serum as a medium for injection-masses, with microscopic demonstration,
by J. Carrington Purves, M.B., C.M., B.Sc. 4. A new Inoculating
Syringe for Bacteriological purposes, with exhibition, by Alexander
Edington, M.B., C.M.

American Society of Microscopists—Buffalo Meeting.
Amer. Mon. Micr. Journ., X. (1889) pp. 156, 223-35, 237-8.
St. Louis Med. and Surg. Journ., LVI. (1889) pp. 288 and 367.
The Microscope, IX. (1889) pp. 214, 244-5, 328-30.
HoveENnDEN, F.—Presidential Address to the South London Microscopical and
Natural History Club.
[A theory of the continuity of life.]
18th Ann. Rep. South London Micr. and Nat. Hist. Club, 1889, pp. 20-7.
Lewis, W. J.—Forensic Microscopy, or the Microscope in its Legal Relations.
[Annual Address to American Society of Microscopists, Buffalo, 1889. ]
Amer. Mon. Micr. Journ., X. (1889) pp. 197-207.
Lowne, B. T.—Presidential Address to the Quekett Microscopical Club.
[On the Anatomy of Insects.] Journ. Quek. Micr. Club, III. (1889) pp. 373-86.
PELLETAN, J.—La Micrographie a l’Exposition universelle de 1889. (Microscopy
at the Universal Exhibition of 1889.)
Journ. de Micrographie, XIII. (1889) pp. 481-93. (Conel.)
Scuort, O.—Ueber Glasschmelzerei fiir optische und andere wissenschaftliche
Zwecke. (On glass-melting for optical and other svientific purposes.)
Central-Ztg. f. Optik u. Mechanik, X. (1889) pp. 243-5. (Concl.)
Zune, A.—Traite de Microscopie médicale et pharmaceutique. (Treatise on
medical and pharmaceutical microscopy.)
[I. Description, choice, employment, and preservation of the Microscope and
accessory apparatus, &c. |
136 pp. and 41 figs. 8vo, Bruxelles and Paris, 1889.

B. Technique.*
(2) Preparing Objects.

Demonstrating Mitosis in Mammalia.{—Dr. B. Solger recommends
the amnion of the rat for demonstrating the mitosis of Mammalia to a
class. The freshly cut-out membranes are placed in a saturated aqueous
solution of picric acid for twenty-four hours. It is then washed in dis-
tilled water previous to immersion in 70 per cent. spirit, the strength of
which is to be gradually increased. The preparations are easily stained
in five minutes in Ehrlich’s hematoxylin, diluted one-half with distilled
water.

Instead of fixing with picric acid and staining with hematoxylin,
excellent results are obtainable by means of Flemming’s mixture and
safranin.

* This subdivision contains (1) Collecting Objects, including Culture Pro-
cesses; (2) Preparing Objects; (8) Cutting, including Imbedding and Microtomes;
(4) Staining and Injecting; (5) Mounting, including slides, preservative fluids, &ec. ;
(6) Miscellaneous. t Arch. f. Mikr. Anat., xxxiii. (1889) pp. 517-8.

832 SUMMARY OF CURRENT RESEARCHES RELATING TO

Mounting Fish-scales.*—Mr. F'. Dubois gives the following directions
for preparing and mounting fish-scales. Place the scales in a small
wide-necked bottle of caustic potash for forty-eight hours, then boil for
a few minutes in plain water and afterwards wash in hot water. Partially
dry the scales between blotters and place in alcohol for a quarter of an
hour to remove all moisture. The scales are then transferred to clove
oil for clearing. Now breathe on a clean cover-glass and apply side
breathed-on to a glass slip to which it will adhere. Place a small drop
of benzol balsam on the cover, put the scale on this, cover it with
another drop of balsam, and set aside for twenty-four hours. By the
following day the balsam will have become thick from evaporation of
the benzol. Now place a drop of fresh balsam on the slide, invert the
cover-glass over it, and the mount is ready for ringing as soon as the
balsam is dry. Dry mounts should be made on cells, the scales having
previously undergone the same treatment.

Preserving Marine Animals.;—M. M. Bedot preserves Siphono-
phora, &., in the following manner :—A 15-20 per cent. solution of
sulphate of copper is made in distilled water. In this the colony to be
fixed is immersed. At the same time as the Siphonophora are plunged
in the copper solution sea-water is also poured in along with them, and
in such bulk that the copper solution is ten times as great. When the
animals are fixed (this happens in a few minutes) a few drops of nitric
acid are added to the solution and the mixture is gently stirred up with
a glass rod in order to prevent the formation of any precipitate. The
Siphonophora are left in the solution for four or five hours, and may
then be hardened. Hardening is best done with Flemming’s mixture :—
1 per cent. chromic acid, 15 parts; 2 per cent. osmic acid, 4 parts;
glacial acetic acid, 1 part. In order to avoid touching the animal or
removing it from the vessel, the fluids should be changed by decanting.
The Flemming’s mixture should be allowed to act for twenty-four hours
and should be twice the volume of the copper solution.

The next operation, that of transferring the animal to alechol, should
be done very gradually. A few drops of 25 per cent. spirit are first
mixed with the fluid by means of a pipette. Gradually the quantity
and strength of the spirit are to be increased, until in fifteen days 70 per
cent. spirit may be used. After this 90 per cent. spirit may be
employed.

Examination of Protozoa.t—The technique to be observed in the
examination of the Protozoa, says Dr. Fabre-Domergue, is divisible into
three heads, the examination during life, fixation, staining, and mounting.

In examining the animals while alive, should they be sufficiently
large as to be visible with the naked eye, then no cover-glass is
necessary, and by gradually diminishing the quantity of water, they are
at last rendered sufficiently motionless to be examined with facility. If
the animals be found too lively they should be left for some hours in
the warm chamber until they have settled down, and this they do usually
at a little distance from the edge either of the drop of water or of the
cover-glass. Certain colouring matters are very useful, especially

* The Microscope, ix, (1889) pp. 184-5, from The Garner, May 1889.
+ Arch, Sci. Phys. et Nat., xxi. (1889) p. 556.
{ Annales de Micrographie, ii. (1889) pp. 545-551.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 833

Bismarck-brown and anilin-violet. The solutions must be perfectly
neutral. The Bismarck-brown stains the organisms without affecting them,
while the anilin-violet stains and slowly kills them at the same time. In
diphenylamine-blue in concentrated solution the animals swim about
unstained and uninjured, hence they show up well against a dark-blue
ground,

For fixation, the author advises osmic acid or a mixture of equal parts
of 1 per cent. osmic acid and 20 per cent. acetic acid. The animal to
be fixed should be placed between slide and cover-glass and observed
through the Microscope. When rendered sufliciently motionless by
pressure on the cover-glass this latter should be prevented from moving
by drops of molten paraffin. ‘lhe fixative may then be run under the
cover-glass in the usual way.

For staining the author recommends picrocarmine, Beale’s carmine,
alum-carmine or methyl-green. If stained with methyl-green the speci-
mens may be mounted in dilute glycerin or Bram’s fluid (water 100,
glycerin 10, glucose 40, camphorated spirit 10). The index of refraction
of the latter is higher than that of the glycerin, and is proportionately
more useful.

The specimens may be mounted in balsam ; if so, care must be taken
to increase the strength of the dehydrating spirits very gradually ; then
creosote, and finally xylol-balsam.

Investigation of Infusoria.*—Dr. W. Schewiakoff gives an account
of his method of studying Infusoria. He always began his observations
with living specimens, which were isolated in a drop of water and fixea
to one spot. The necessary pressure was regulated by the removal or
addition of water. ‘The best water in which to place the organisms is
that in which they were found, and which had been filtered. Observa-
tions can best be made on starving specimens. As soon as the animals
were completely free of food, artificial feeding was commenced; this of
course varies with the habit of the infusorian; those that live on uni-
cellular plants may well be provided with drops of animal fat, which
can be easily enough obtained by squeezing a small crustacean. Those
that live on Bacteria were provided with indigo or carmine which showed
up the characters of the digestive system. When the animals had had
enough food they were again placed in clean water and observed further ;
by this means the position of the anus may, among other things, be made
out.

By pressing on the cover-glass with a dissecting-needle the animal
is forced to break itself up. As this happens the trichocysts may be
observed, the mouth and pharynx be more conveniently examined, and
the macro- and micro-nuclei isolated.

To kill specimens the best reagent is the vapour of 1 per cent. osmic
acid; larger forms, such as Dileptus, must be put in fine tubes with as
little water as possible and be placed for some seconds in 1 per cent.
osmic acid, when death will be found to follow very suddenly. Pre-
parations thus made are well adapted for the study of the strie of the
body and the protoplasmic structures. When cilia, sete, or mem-
branelle are to be studied a 5-10 per cent. solution of soda is recom-
mended. The organisms should be put in glycerin when we desire to
study them from different sides. A solution of 1 per cent. acetic acid,

* Bibliotheca Zool., vy. (1889) pp. 5-7.
1889. 3M

834 SUMMARY OF CURRENT RESEARCHES RELATING TO

to which a trace of iodine-green has been added, is a good staining
reagent.

Mounting Infusoria.*—Prof. C. W. Hargitt places some water con-
taining the animals (paramecia, vorticella, hydroids) on a watch-glass,
and removes as much as possible with a pipette, and completes the
reduction by means of a thread siphon. The animals are next killed
with a saturated solution of corrosive sublimate, Lang’s fluid, which is
essentially the same as the foregoing plus a small quantity of acetic
acid, osmic acid, or picrie acid. After killing, it is only necessary to
harden the protoplasm by the ordinary method of alcohol of increasing
strength, then to stain them, and afterwards mount in balsam.

Transference from one medium to another is best effected by means
of the thread siphon. By this method the author has secured amoebee
naturally expanded, and exhibiting almost every phase of their life-
history.

The final mounting may be done with equal success in glycerin or
glycerin-jelly.

Medium for mounting Starches and Pollens.;—Mr. A. P. Brown
advocates the use of the following medium for starches, pollens, and
vegetable tissues :— Selected gum arabic, 2 oz.; glycerin and distilled
water, each 14 oz.; thymol, 1 gr. Put in a wide-mouthed well-corked
bottle, and place in a warm situation. Stir occasionally until perfectly
dissolved. Then strain through linen and set aside for about a week to
get rid of air-bubbles, or filter through a “hot filter.”

To mount starches or pollens a clean slide is breathed on and then
dusted over with the starch or pollen, excess of which is to be removed
by tapping the slide gently against the table. A drop of the mounting
medium is then placed on the slide and the cover-glass imposed. If any
air-bubbles are in the medium they must be picked out with the needle.
The cover-glass may be ringed round with cement directly.

Preparing Diatoms.— Mr. C. Haughton Gill writes :—When cleaned
and dry diatoms are soaked in a concentrated solution of ferric chloride
(perchloride of iron) for some time aJl hollow spaces contained in the
frustules become charged with the iron salt. If they be now transferred
to an acid solution of potassium ferrocyanide, Prussian blue will be
formed both outside and inside all hollows and cavities. On washing
and levigating with water the outside unconfined portion of the precipi-
tate can be washed away in great part, while those portions which are
more or less surrounded by walls of silica remain in place, and serve tu
clearly mark the position and limits of the spaces containing them.

Evaporating a solution of sodium platinum chloride on cleansed
diatoms, and igniting the whole with addition of some crystals of oxalic
acid, serves to charge the minute cavities, to be described later, with
a deposit of spongy platinum.

Pinnulariz under either of these treatments show their coarse ribbing
to consist of ribbon-shaped tubes contained in the walls of the frustule.
Pleurosigma, Stauroneis, Cocconema, &c., show their “dots” to be
spaces which can be filled by foreign bodies. Coscinodisci have the
openings into their lacune so large that the precipitates for the most

* Amer. Mon. Micr. Journ., x. (1889) pp. 183-4.
+ Amer. Journ. of Pharmacy, April 1889.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 835

part get washed out in the course of mounting, but the cell-walls take so
much of colour that their shape and parts can be clearly distinguished.

New Application of Photography to Botany.*—M. F. Fayod pro-
poses a new application of photography for the purpose of obtaining
accurate representations of leaves, &c., in order to study the arrangement
of the vascular bundles. The method consists in employing the leaf
itself as a negative. It is placed on a perfectly clean plate in an ordinary
photographic frame, and covered by a sensitized leaf of albuminized
paper, such as is usually employed for positive prints. The sensitized
paper is pressed close against the leaf, and exposed to the sun in the
ordinary way, generally for from 5-20 minutes. The veins being
nsually more translucent than the mesophyll, the portions of the sen-
sitized paper situated immediately below them become black more
rapidly than those below the mesophyll, the green colour entirely
absorbing the rays of light; the leaf is reproduced in white on the black
groundwork of the paper; every-vein being represented by a black line
of intensity in proportion to its strength.

Production and Preservation of Saccharine Crystals.{—Mr. Wright
Astley states that saccharine may be crystallized by two methods and two
differently shaped crystals produced. In the one they are nearly always
cube-shaped, in the other nearly always rhomboidal. The first method
is performed on an ordinary slide. Take about 6 grams of the pure
powder and mix in a 2 oz. bottle three-fourths filled with water. Then
pour two or three drops of the mixture on a slide ; surmount this with a
cover-glass, which clip lightly, and hold over a spirit-lamp until it just
boils. It is better to have too much than too little fluid on the slide.
Upon cooling crystals will have formed. A similar result is also
obtained by putting 6 grains of the pure powder in a 2-oz. bottle and
pouring boiling water over this and keeping up the temperature for
4 or 5 minutes. On cooling crystals will have formed.

After a good mount has been secured by crystallizing on the slide,
brush off the loose powder round the edge of the cover-glass, and this,
with care, will adhere while a ring of brown cement is run round; then
finish in the usual way.

Crystals formed in the manner above mentioned may be kept in the
mother liquid in a cell. Or make « cell and place in it a drop from the
bottle containing the crystals; leave it until the water has evaporated
from the cell (24 hours) ; then finish in the usual way.

Latuam, V. A.—Practical Notes on Histology.
(Special methods for examination of the eye.]
Journ. of Microscopy, II. (1889) p. 217.

(8) Cutting, including Imbedding and Microtomes.

Imbedding in Glycerin Soap.{—This method, says Prof. A. Poli,
has two great advantages, the soap is very soluble in water and is very
transparent. Hence for delicate botanical objects it is invaluable.

* Malpighia, iii. (1889) pp. 120-8 (1 pl.).

t+ Trans. Manchester Micr. Soc., 1888, pp. 15-7.

¢ Journ. de Mier., xiii. (1889) pp. 337-40, from ‘ Malpighia.’
3M 2

836 SUMMARY OF CURRENT RESEARCHES RELATING TO

The procedure for imbedding is as follows. A mixture of equal
volumes of glycerin and 96 per cent. spirit are heated in a water-bath
from 60°-70° C. Into this are dropped as many small pieces of glycerin
soap as will dissolve. The vessel best suited for the foregoing is a
flask, the neck of which may be plugged with cotton-wool in order to
prevent the spirit from evaporating too rapidly. The liquid thus
obtained is yellow and transparent, but with a slight opalescence. It is
then poured into a capsule or paper box. While it is still warm the
object to be cut, and which has been removed from strong spirit, is fixed
in the desired position by means of needles until the soap has solidified.
Large pieces must be soaked for some time in a cold saturated solution
of soap before they are removed to the hot fluid.

The imbedding mixture, which should be kept in a stoppered bottle,
melts easily at about 40° C. ;

Very small objects may be readily imbedded by placing them in a
drop of the warm solution on a cork, and then covering them with
another drop. These small quantities of soap get quite hard in about a
quarter of an hour. -

The sections are easily freed from the soap by merely washing them
in lukewarm water, while the alkalinity of the soap aids in clearing up
the specimen.

In practice it is found advisable to use two solutions, one for firm,
the other for delicate objects. The ingredients of the former are :—90 per
cent. spirit, 82 cem.; pure glycerin, 32 ccm.; soap, 64 gr. The second
contains only 32 ccm. of soap, and is consequently much softer. The
harder mass may be sectioned in a Ranvier microtome.

Dextrin Mucilage for Imbedding.*— For those who use the freezing
microtome it will be found useful, in the present high price of gum-
arabic, to know that gum dextrin answers just as well as the latter, and
costs only about one-fifteenth as much. Mr. T. L. Webb writes upon
this point to the ‘ Provincial Medical Journal’ as follows :—“TI find that
by making an aqueous solution of carbonic acid (about 1 part of the acid
to 40 parts of water) and dissolving therein sufficient dextrin to make a
thick syrup, a medium is obtained which is superior to the time-honoured
gum and sugar in three ways. It freezes so as to give a firm support
without becoming too hard; it keeps better than gum, in which several
kinds of fungi are apt to grow; and it is much cheaper, costing only
about fourpence per pound, while powdered gum acacia costs five
shillings. Dextrin dissolves but slowly in cold water, so that a gentle
heat is advisable when making the mucilage.”

Wilks’ Improved Microtome.}—Mr. G. Wilks describes an improved
form of microtome designed by himself, the principal feature of which is
that the cutting-plate, or head, is removable; it is fitted to the lower
part by a socket-joint, and secured either by a bayonet-catch or a screw.
The hole in the plate or head is bored taper, and is 1/16 in. less in
diameter at the outside than in the well or tube of the microtome, thus
effectually counteracting the effect of shrinkage in the imbedding
material. ‘The diameter of the well is also much less than in the older
form of microtome.

* St. Louis Med. and Surg. Journ., lyii. (1889) pp. 231-2.
+ Trans, Manchester Micr. Soc., 1888, pp. 86-7.

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 837

Thin Sections of Timber.*—For showing the structure of timber
Mr. R. B. Hough employs frames made of cardboard holding three
samples of wood, each being about 2 in. wide and 5 in. long, and from
1/80 to 1/200 in. thick. These exhibit the wood in three relations; one
slice being transverse across the grain, another running radially from
the outside towards the heart, and a third is a tangential section. The
first and second show both the sapwood and the heart. They also reveal
the grain and the structure of the wood in a most beautiful manner.
These various frames are arranged in book form for the purposes of
study and examination. They retain all the characteristics of wood and
are easily recognized, while the effect of the light shining through them
is to show the peculiarities of the grain even more emphatically than
would be the case if one were looking at a mass of the wood,

(4) Staining and Injecting.

Iodized Heematoxylin.j—Sig. F. Sanfelice having noticed that tissues
which had been treated with tincture of iodine stained more uniformly,
devised a compound of logwood and iodine. This mixture possesses the
advantage of giving the same stain as Boehmer’s hematoxylin to tissues
previously treated with tincture of iodine, and of thoroughly penetrating
pieces to be stained in toto.

Another advantage is that, owing to its antiseptic qualities, it keeps
better than most hematoxylin solutions. It is prepared by dissolving
0:70 gr. hematoxylin in 20 gr. absolute alcohol, and 0°20 ger. alum in
60 gr. distilled water. The first solution is poured drop by drop into the
second. The fluid is then exposed to the light for 3-4 days; 10-15 drops
of tincture of iodine are added, the fluid is shaken up and allowed to
stand for some days. ‘Tissues stain in this solution in 12-24 hours;
they are then transferred to 90 per cent. spirit acidulated with acetic
acid, in which they are left for the same time.

Staining the Flagella of Spirilla and Bacilli.t—Dr. Trenkmann’s
method for staining flagella is as follows :—

A small drop of fluid containing spirilla is placed on a cover-glass ;
to this is added a large drop of distilled water, and the two intimately
mixed. When dry, the cover-glass is placed at once in a fluid which
consists of 1 per cent. tannin and 1/2 per cent. hydrochloric acid. In
this fluid the preparation remains 2-12 hours, and then having been
washed is stained in dahlia (2 drops of a saturated alcoholic solution
to 20 water), fuchsin (2-4 drops of a saturated alcoholic solution to
20 water), gentian-violet (1 drop to 80 water), methyl-violet (1 drop to
80 water), methylen-blue, iodine-green, methyl-green, vesuvin, Victoria-
blue. In the staining solution the preparation remains 2—4 hours, it is
then washed in water and examined. By all these anilin dyes cilia
are stained, most strongly by dahlia, fuchsin, or methyl-violet, but still
better by carbolic fuchsin (2 drops to 20 of a 1 per cent. carbolic acid).

Another method of staining is by means of catechu. Excess of
powdered catechu is macerated in water for some days and the extract
filtered. To 4 parts of this catechu solution are added 1 part of a
earbolic acid solution, and in this the cover-glass, prepared as before, is

* Amer. Mon. Micr. Journ., x. (1889) p. 187.
+ Journ. de Micrographie, xiii. (1889) pp. 335-7.
} Centralbl. f. Bakteriol. u. Parasitenk., vi. (1889) pp. 433-6.

838 SUMMARY OF CURRENT RESEARCHES RELATING TO

placed for 2-12 hours. The best stains after this were dahlia and
fuchsin.

A third method is by using a strong solution for 2-12 hours of
extract of logwood. After this mordant fuchsin is the best dye. This
process is improved by the addition of acids, as hydrochloric acid, 1 per
cent.; gallic acid, 1/2 per cent.; carbolic acid, 1—2 per cent.

By these methods the author has been able to show not only cilia,
but tufts of them in many spirilla. The micro-organisms specially
alluded to are Spirillum undula, Vibrio vagula, and small vibrios.

Impregnating Tissues by means of Methylen-blue.*—Prof. A. S.
Dogiel says that methylen-blue is an excellent substitute for silver
nitrate for the purpose of impregnating tissues such as those made up
of connective tissue, and also serous membranes. The method of
impregnation is as follows:—A 4 per cent. solution of methylen-blue is
made in physiological salt solution. In this is placed the piece of tissue
quite freshly cut out for 10-20-30 minutes, according as it is desired
to show merely the boundaries between the cells, or to obtain a negative
picture of the lymph-spaces and vessels.

In the former case it is sufficient to leave the tissue in the solution
for only a few minutes; in the second it is better to remove the super-
ficial epithelium from the serous membranes, and leave the tissue in the
solution for fifteen to thirty minutes, in order that it may be thoroughly
saturated with the dye. At the expiration of this time the preparation
is removed and transferred to a saturated solution of picrate of
ammonia, wherein after having been carefully washed, it is allowed to
stay for half an hour or longer. It is then washed again in some fresh
picrate of ammonia, and examined in dilute glycerin.

If it be desired to preserve the preparation for some time, it is
advisable to place it in glycerin saturated with picrate of ammonia.
The plate shows that the method gives satisfactory results.

Impregnation in Black of Tissues.t—M. Flot adopts the following
methods for impregnating tissues, wherein a coloured chemical precipi-
tate is formed by the reaction of two different bodies on each other, and
it is therefore owing to this chemical deposit that the preparations are
stained :—

1) Perchloride of iron and tannin. In this are required a concen-
trated solution of iron perchloride and a solution of tannin in alcohol,
made to a syrupy consistence. Ina watch-glass are placed two drops of
tannin, and in another three or four drops of perchloride of iron; both
are filled up with distilled water. The section previously treated with
hyposulphate of soda and washed is placed for a minute in the tannin, and
then after being passed through water, transferred to the perchloride,
whereby it is stained a deep black. As soon as this occurs, it is removed
to water and left there for five minutes. Afterwards it is mounted in
the usual manner.

(2) Sulphate of copper, bichromate cf potash, and extract of logwood.
Ten per cent. solutions of copper sulphate and of bichromate of potash
are prepared. Five drops of each solution are placed in a watch-glass,
and this is then filled up with distilled water. Another watch-glass 1s
filled with a strong solution of extract of logwood. The section is first
placed in the logwood solution for about five minutes, and is then

* Arch. Mikr. Anat., xxxili. (1889) pp. 440-5 (1 pl.),
+ Revue Gen. de Botanique, i. (1889) pp. 290-1.

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 839

transferred to the copper and bichromate solution, wherein it becomes
stained black. Sections stained in this way are extremely valuable for
photomicrography. ‘The sections thus stained may be mounted in
acetate of potash, glycerin, or in balsam.

(5) Mounting, including Slides, Preservative Fluids, &c.

Method for fixing Serial Sections to the Slide.*—Dr. Gallemaerts
recommends Drash’s method for fixing sections to the slide. It is per-
formed as follows :—

(1) Make a saturated solution of gun-cotton in acetone, and then add
enough absolute alcohol to the solution to make a very thin fluid.

(2) Cover the slide with a thin layer of the liquid.

(3) Arrange the sections, then moisten the slide with a brush dipped
in absolute alcohol in order to dissolve the coat.

(4) Mop up the sections with blotting-paper by pressing several folds
down on the slide with the finger.

(5) Warm the slide until the paraffin melts.

(6) When cool dissolve the paraffin in xylol and mount in balsam.

(7) If the preparations are not stained, after the xylol wash with
alcohol ; then place them in the stain. When stained, wash in water,
and then pass through alcohol and xylol to balsam.

Apparatus for fixing down Series of Sections.j—Dr. I. Dionisio
has devised an apparatus for facilitating the manipulation of series of
sections. ‘The idea of the apparatus consists in keeping the sections on
the slide during the manipulation by means of a fine wire sieve, the
meshes of which are proportionate to the size of the preparations.

The apparatus consists of a circular flat ring of metal a, upon which

Pre. 13:

<=) —
SS rae
iM

lies the oblong frame b. From the long sides of b two pieces d d extend,
and end in rounded extremities, through which pass two screws ce.
These connect the two movable parts, and when the screw-head e is
turned down, these two parts are firmly fixed together.

Sections fixed up in this way can be treated thoughout the various
stages of staining, washing, dehydration, &., but it is obvious that the
instrument cannot be employed with reagents which act upon it (acids,
&c.); hence its use would appear to be somewhat limited.

* Bull. Soc. Belg. de Micr., xv. (1889) pp. 56-7.
+ MT. Embryol. Instit. Univ. Wien, 1888, pp. 80-4 (1 fig.).

840 SUMMARY OF CURRENT RESEARCHES RELATING TO

Section-fixing.*—Dr. E. D. Bondurant suggests the following slight
variation of the method generally adopted in the use of the clove-oil-
collodion process, which he has found to combine the convenience and
readiness of application of a liquid fixative with the undoubted advan-
tages offered by the dry-film methods, in that it allows the preliminary
arrangement of the section or a number of sections on the slide, and the
easy removal of folds and wrinkles, which latter, especially with large
thin sections, is often impossible if tissue must lie as it falls,

Place the section (paraffin imbedded) on a perfectly clean slide.
Arrange and smooth out folds with 2 camel’s-hair brush dipped in
alcohol. Hold an instant over an alcoholic flame until the paraffin
partially melts and the section adheres. Paint over the section and
slide a thin film of the collodion mixture. Press down with the thumb
a bit of tissue-paper coated with same mixture, in the manner recom-
mended by Dr. Reeves, to insure close contact. Planish with mounting
forceps, remove the paper, and place the slide on the brass table or water-
bath at the melting-point of paraffin, until the clove oil is evaporated, when
the section will be’ found firmly attached, and the slide can be passed
through benzol, alcohol, stains, &c., without danger of separation.

Mayer’s albumen process can also be used as above, and is satisfactory.

Frenzel’s gutta-percha and Threlfall’s

Fig. 114. caoutchoue methods are also reliable, but

the author thinks the collodion process,

used in the manner described, is most

available and most certain in its results,

and he, for one, feels no need of a better
plan.

Slide-rest for the Manipulation of
Serial Sections.| — The apparatus in-
vented by Dr. J. Dewitz for the manipu-
lation of several slides at a time, is made
of glass rod, and can therefore be easily
constructed by any person who possesses
a blow-pipe and some glass rod or tubing.
An inspection of it will show at once the
easiness of the manufacture. Glass rod of
two different thicknesses is required ; the
thicker is for the external part of the
frame, the thinner for the internal. The
illustration shows a frame suitable for
five slides, or ten if placed back to back,
but of course, as any number of turns
can be given to the parallel bars, an apparatus might be constructed for
an indefinite number of slides. ‘The slides are slipped in from above, ©
and it will be seen that they can be kept in good position without danger
of interfering with one another.

Mounting “selected ’ Diatoms.t—Mr. H. Morland “ has two methods
of preparing slides of selected diatoms,” one where the diatoms are gummed
down, the other where no cement is used. Choose only the finer and

* The Microscope, ix. (1889) p. 191.
+ Arch. f Mikr, Anat., xxxili. (1889) pp. 416-8 (1 fie).
{ Journ. Quekett Micr. Club, iii. (1889) pp. 318-30 (2 figs.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 841

flatter diatoms. First allow a drop of water containing the material to
evaporate on a slide, taking care that the diatoms are not crowded
together. By aid of a mounting-bristle, select and lay aside a number of
diatoms. Transfer as many as required to the slide, placing them about
half an inch to one side of the ruled glass disc in an inked square or
circle, so that they can be readily found when wanted. Next breathe on
a cover-glass and press it down on the slide, to which it will adhere
sufficiently long and firmly for all practical purposes. Place the slide
under the Microscope and then arrange the diatoms, as desired, on the
cover-glass, and if necessary, owing to dirt or bits of broken diatoms,
previously wash in drop of distilled water.

Should the diatoms be concave, the concavity must be placed away
from the cover-glass, otherwise when the styrax is applied an air-bubble
may be included.

When arranged, breathe gently on the diatoms through the breathing-
tube, watching them the while through the Microscope. This causes the
diatoms to adhere: too much moisture is easily removed by reversing
the process.

The mounting-slip is now placed on the turntable and carefully
centered, and then a small “ guide-ring,” about 1/10 in. in diameter, is
traced round the arranged diatoms with a mixture of gum and some
colouring matter, such as lampblack. The slip intended for use with
the cover can also now be ringed on the under side.

The next thing is to have an iron block heated to 180° F. On this
are placed two small pieces of brass about 1 in. apart, on one of which
is placed the prepared cover. A drop of styrax is now placed on the
centre of the slide; another is then laid on the hot block in order to
remove all traces of its benzole solvent. While still hot it is turned
over and lowered gently down on the cover-glass. If any air-bubbles
are included, let the slide remain on the hot block until they disappear.
If balsam be used instead of styrax, it must be applied cold.

If the diatoms be large, heavy, much concave, or beset with spines,
they must be fixed down with some cement. The author, who recom-
mends gum, first applies the minutest drop of gum arabic dissolved in
water by means of a glass rod to the centre of the cover-glass, after this
has been fixed to the ruled disc by means of the breath. This drop is
then allowed to dry, and any desired consistence may be imparted to it
through the breathing-tube. The diatoms are then arranged in the
manner desired, and mounted in balsam.

Carbolic Acid in Mounting.*—Mr. F. T. Chapman considers that
carbolic acid is superior to the ordinary media used for mounting
insects. The strongest uncoloured acid should be used: small insects
can be cleared therein in a few minutes, and immediately mounted in
balsam without further treatment.

The solid acid may be liquefied either by the addition of 5-10 drops
of water to the ounce, or if it can be used warm, by the aid of heat.
The time required for clearing an object varies, the head of the common
house-fly taking about a week.

Objects to be mounted in benzole balsam should be first passed
through oil of cloves in which they are allowed to remain until all
surface agitation has disappeared.

* Amer. Mon, Micr. Journ., x. (1889) pp. 127-8.

842 SUMMARY OF CURRENT RESEARCHES RELATING TO

The disadvantage inherent to carbolic acid of becoming embrowned
by time and exposure to light is retarded by using 95 per cent. aleohol
as the liquefying agent instead of water.

SHERMAN, W. W.—Notes on Balsam Bottles.

[Simple and effectual device for preventing the smearing of balsam and other
resinous and sticky substances, with the consequent adhesion of the cork to
the neck cf the bottle. A piece of soft whalebone is bent and placed in the
bottle, so that superfluous fluid may be removed on its arch. Also suggests
the use of a glass-capped bottle. ]

The Microscope, 1X. (1889) p. 277.

(6) Miscellaneous.

Apparatus for Isolating Objects.*—-Dr. W. Behrens gives an account
of an ingenious apparatus intended to save the labour of shaking out or
removing certain parts from a specimen. It consists of a circular tin
box, fig. 115 6, containing a water-wheel to which water is carried

Fic. 115.

through the tube a, and removed by a similar tube not shown in the
illustration. The water-wheel drives a circular metal dise c, in which,
in one radius, is a series of holes. Into any of these holes is fixed a
screw which connects the forked end of a long lever d to the apparatus.
At the other end of the long piece d is a clamp for holding the test-
tube, which is plugged when the apparatus is in motion.

The amplitude of the movement imparted to the test-tube depends of
course on the distance of the screw from the end of the lever.

a Behrens, Kossel, and Schiefferdecker, ‘Das Mikroskop,’ i, (1889) pp. 161-2
C1 fig.).

ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 8438

New Method for the Bacteriological Examination of Air.*—The
microbiometer of Dr. HE. Forstetter consists essentially of a U-shaped
glass tube (fig. 116) E H, at one end of which isalargish bulb M. The
latter is connected by a short neck with a test-tube B, the inferior
extremity G of which is made bulbous in order to contain a sufficient
quantity of gelatin. C is the aperture of entrance, and B that of exit.

Into the U-shaped tube is introduced about 10 ccm. of distilled
water E E, and into the bulb G 15 cem. of 12 per cent. nutrient
gelatin. The apertures having been plugged with cotton wool, the
apparatus is sterilized in the usual manner. When required for analysis
the plug is removed from © and the aspirator fitted in B, and air drawn
through at the rate of about 10 litres an hour. The experiment over, the

Fig. 116. Fie. 117.

Fictas
iG \
u
“C
4
We ?
or

iy -

orifices are replugged, and then the gelatin melted by the aid of very
gentle heat. ‘The instrument is then placed in the horizontal position,
fig. 117, so that the water and gelatin mix together in the bulb M. When
thoroughly mixed, the fluid is dispersed over plates for the cultivation
of this organism. The removal of the gelatin mixture is easily effected
through the opening B.

The aspirator employed by the author is a portable one capable of
drawing in 20 litres of air an hour. It consists of a clockwork arrange-
ment acting on two rubber bellows, shaped like a Chinese lantern. A
needle on a dial-plate indicates the quantity of air which has passed
through.

Examining thin Films of Water.|—Mr. F’. Hovenden draws attention
to the interesting phenomena presented by a thin film of water under
the Microscope. The film may be obtained by simply breathing on the

* Annales de Micrographie, ii. (1889) pp. 567-71 (2 figs.).
+ 18th Ann. Rep. South London Mier. and Nat. Hist. Club, 1889, pp. 10-1.

844 SUMMARY OF CURRENT RESEARCHES, ETC.

blade of a knife, when the steam will condense and the disappearance of
the water can be observed with a half-inch power. As the globules
evaporate, they appear to leap into the air, the actual point of final
disappearance, however, being difficult to detect. Some curious
questions as to molecular action are raised by this expcriment, as well
as by those which he suggested should be made in connection with thin
sections of iron.

Kurz’s Transparent Microscopical Plates.— Dr. W. Kurz, of
Vienna, has edited plates which contain representations true to nature
of typical preparations intended to produce the impression of a micro-
scopic image. They are printed in transparent colours, and during
observation are turned towards the light. The special advantages
claimed for this mode of demonstration over the use of the Microscope
are that a whole school can observe at the same time the object
described, so that the pupils need not leave their seats and the teacher
can draw their attention to every single part of the object represented.

Duncan, A. W.—The Microscopical Examination of Food for Adulteration.
Trans. Manchester Micr. Soc., 1888, pp. 49-52.
FREEBORN, G. C.—Histological Technique of the Blood. .
Amer. Mon. Micr. Journ., X. (1889) pp. 217-22 (1 pl.).
WuHELPLEY, H. M.—Microscopical Laboratory Notes.
The Microscope, 1X. (1889) pp. 189-40.

( 845 )

PROCEEDINGS OF THE SOCIETY.

Mretina or 9TH Ocrosrr, 1889, ar Kine’s Cotiecr, Srranp, W.C.,
THE PresIDENT (Dr. C. T. Hupson, F.R.S.) In THE Cuarr.

The Minutes of the meeting of 12th June last were read and con-
firmed, 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.

Braithwaite, R., The British Mo-s Flora. Pt. xii. pp. 57-184, From
Repl Sree CS VOs WOnGGnemhe sO) yee acriect a tots, lige eekesh vate Ne The Author.
Cooke, M. C., Toilers in the Sea. viii. and 373 pp., 4 pls., and{ _ 7%¢ Society for
70 figs. (Svo, London, 1889)... .. .. «ww 4.) Promoting Christian

Knowledge.

Deby, J., Bibliotheca Debyana. Catalogue of Books in the
Library of J. Deby, M.E., F.R.MLS., vol. i., 151 pp. (8vo,
houd ons SSS) heres Lehman fee eras ial rape eelL oe\ e @ 2
Hudson, C. T., and P. H. Gosse. The Rotifera or Wheel-ani-
malcules, Supplement. vi. and 64 pp. and 4 pls. (8vo,
WMondon-slSSO)\ey ems wataacemeescn ince Jaed,) sat W's eet
Matthews, C. G., and F. E. Lott. The Microscope in the
Brewery and Malt House. xxi. and 198 pp., 22 pls. and
30 figs. (8vo, London and Derby, 1889) .. .. .. .

The Author.
Messrs, Lonyman.

The Authors.

The President said, with reference to the ‘Supplement, that the
original notion of Mr. Gosse and himself was to have made their book
on the Rotifera complete; but whilst it was in progress of publication
so much was done, and so many new species were added by Mr. Cosse,
that they found it was not possible to include all, and the foreign
Rotifera had also to be put on one side. Later on, when he had the
foreign species under consideration, he began to be afraid that they
would have to be permanently left out; bnt he found that their own
list contained so many foreign forms, that it was eventually possible to
include the others, and although this part had been done briefly, it had,
he believed, been done completely, so that the ‘Supplement’ included
everything which was not contained in the original work.

Mr. Crisp called attention to the confusion in ‘The Microscope in
the Brewery’ in connection with working distance and magnifying
power. He also called attention to the publication of Part 12 of
Dr. Braithwaite’s ‘ British Moss Flora,’ which came fully up in point
of excellence to those which had preceded it.

Mr. Crisp said he had to trouble the meeting with a personal matter,
and that was to announce that he was obliged to retire from the
Secretaryship of the Society, and from the eonduct of the Journal. The
Council had been aware for some years that his continuance in office
was contingent upon certain business arrangements, and though that
contingency had happily been long deferred, it had now taken effect,

846 PROCEEDINGS OF THE SOCIETY.

and the whole of his attention was absorbed to an extent that would not
allow of his offering himself for re-election. There would, he anticipated
be no difficulty in continuing the Journal on its present lines, while he
was sure there were many Fellows both able and willing to undertake
the duties of microscopical Secretary. It was with the greatest reluctance
that he had found it necessary to resign, but, at the same time, he had
always felt that twelve years of one régime was as much as was good for
a society.

Mr. John Meade’s communication was read on ‘‘ Stereoscopic Photo-
micrography,” in which he claimed to have been the first to produce
stereo-photomicrographs. Specimens were sent in illustration.

Mr. J. D. Hardy said he had a photo-micrograph which he had made
on the same principle about seven years ago. It was of the eggs of the
domestic fly.

Mr. E, M. Nelson said that the plan of taking stereoscopic photo-
micrographs in this way had been known for a long time. One way in
which they were done, was to cover up alternately each half of the
objective, taking a photograph from each, the two being afterwards
mounted as a stereoscopic picture.

Mr. Crisp said the subject had been exhaustively dealt with many
years ago by Dr. Fritsch in his ‘Ueber das stereoskopische Sehen im
Mikroskop und die Herstellung stereoskopisher Mikrotypien auf photo-
graphischem Wege” (1873), while Dr. Stein’s ‘ Das Licht’ contained a
good summary of the subject.

The President said he had brought with him for inspection three
photomicrographs of one of the new rotifers mentioned in his ‘Supple-
ment ’—Gomphogaster areolatus. They were unfortunately not good
specimens, but though very indistinct, they were sufficiently like the
drawing shown at a previous meeting to enable the creature to be recog-
nized as the same. It was necessarily very difficult to get a good
photograph of an object of this sort.

Mr. E. M. Nelson said he had brought for exhibition a new
elementary centering substage which he thought was likely to be useful...
It was fitted in the simplest manner by placing two lugs under the main
stage, and the movement was given to it with the finger; it was very
inexpensive, and was only designed to render the ordinary student's
Microscope of a higher degree of efficiency by providing it with an easy
method of correctly centering the condenser and diaphragm.

Mr. J. Mayall, jun., thought that in this case Mr. Nelson had really
hit upon a novelty of design. The need of a simple and accurate
centering substage for inexpensive Microscopes had long been a serious
impediment to the skilful use of such Microscopes. Mr. Nelson’s new
substage would add greatly to the efficiency of students’ Microscopes at
small cost. He believed that a few hours’ practice would enable any one
to master the use of the new substage, and he thought Mr. Nelson was
very much to be congratulated upon its production.

The President said Mr. Rousselet was showing under his Microscope
a specimen of Limnias curnuella, a new and very pretty creature which

PROCEEDINGS OF THE SOCIETY. 847

they would find well worth looking at. In this animal the tube, instead
of being made with a simple bore, sometimes with a straight axis and
sometimes curved, was in the form of a screw, being twisted round upon
itself. Mr. Rousselet’s drawing showed this very clearly. Mr. Western
also had a curious rotifer for exhibition.

Mr. Western said it was a specimen of Rotifer citrinus which was
found by Mr. Chapman on Wimbledon Common.

The President mentioned that Pedalion was to be had in many places
in the neighbourhood of London about a month ago, where it had not
been previously found, though Mr. Shepherd had found it repeatedly in
the lily tank at Eaton Hall, near Chester. It was very curious to note
how, when a rotifer made its appearance in one locality it was generally
found in a number of other places surrounding, as if the eggs were
carried about and distributed by the wind along with the dust. He also
wished to draw a picture of what Mr. Rousselet had called his attention
to in connection with the small vibratile tags attached to the lateral
canals, the use of which had been so difficult to make out in the case of
Asplanchna. He had not mentioned it in the Supplement to the
‘Rotifera,’ but he found that in Daday’s last memoir, printed in
Hungarian, it was shown quite plainly. Having made and explained
drawings of the structure on the blackboard, the President said that the
conclusion he had come to was that the hairs were intended to protect
the openings from the intrusion of any bodies which might tend to
obstruct the tubes, and if this was so it would seem to demonstrate that
there were openings. He had seen these hairs frequently loaded with
matter apparently strained out from the water.

Mr. Ahrens’s description was read of his new patent polarizing
binocular Microscope for obviating the difficulty of using analysing
prisms with the double tube. The inventor uses for an analyser a black
glass prism, set above the objective with a horizontal side upwards.
Two faces are symmetrically inclined to the optic axis at the polarizing
angle. The pencil is thus reflected at the proper angle, and at the same
time divided into two parts, which are then reflected up the two tubes
either by prisms or by plane reflectors (ante, p. 685). |

The President said the Fellows must have heard with great regret
of the deaths of the Rev. M. J. Berkeley and Dr. G. W. Royston-Pigott,
the former an Honorary, and the latter formerly an Ordinary Fellow of
the Society. They were both too well known to need any statement
from him as to their work.

Mr. Crisp said they had also heard of the death in America of
Mr. C. Fasoldt, sen., so well known as a ruler of fine lines.

Prof, Abbe’s paper, “ Notes on the Effect of Illumination by means
of Wide-angled Cones of Light,” was read (supra, p. 721).

The President thought it would be obvious that a paper like that of
Prof. Abbe’s could hardly be followed when read to the meeting—
although full justice had been done to it in that respect by Mr. Crisp.
It could only be fairly dealt with when seen in print in connection with
the figures which illustrated it.

Mr. T. F. Smith said that personally he had never objected to the

848 PROCEEDINGS OF THE SOCIETY.

diffraction theory itself; but only to certain conclusions which some
persons had drawn from it.

Mr. T. F. Smith read a paper “On the Ultimate Structure of the
Pleurosigma Valve” (supra, p. 812).

Prof. Bell said he was disappointed to find that a specimen which he
had brought for exhibition at the meeting was dead. It was a fine
specimen of Virgularia mirabilis, which had been sent to him by post
from the west coast of Scotland by Mr. Gathorne Hardy. He had to
attend a committee during the afternoon, and, having the tube in his
pocket, the warmth had proved too much for it, and it had broken up
and disintegrated. He regretted that he was in consequence unable to
show what was certainly a very interesting and beautiful organism, so
that for the moment they would have to be content with the knowledge
gained by his experience, namely, that it was now possible to get living
specimens delivered in London from Scotland in a healthy condition by
the parcel post.

The following Instruments, Objects, &c., were exhibited :—

Prof. Bell :—Virgularia mirabilis.

Dr. Hudson :—Three Photomicrographs of Gomphogaster areolatus.

Mr. J. Meade :—Stereoscopic Photomicrograph of head of Crane Fly.

Mr. Nelson:—Baker’s Student’s Microscope with new elementary
centering Substage.

Mr. Rousselet :—Limnias cornuella.

Mr. IT. F. Smith :—Valve of Pleurosigma formosum in illustration of
his paper.

Mr. Western :—Rotifer citrinus.

New Fellows :—The following were elected Ordinary Fellows:—
Surg. P. W. B. Smith, R.N.; and Surg. V. Gunson Thorpe, R.N.

Mrrtinc or 137TH Nov., 1889, at Kine’s Contece, Srranp, W.C.,
THE PresipenT (Dr. C. T. Hupson, F.R.S.) in THe Cuarr.

The Minutes of the meeting of 9th October 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
Behrens, W., A. Kossel, and P. Schiefferdecker, I’as Mikroskop

und die Methoden der mikroskopischen Untersuchung.

Band i., viii. and 315 pp., 193 figs. (8vo, Braunschweig, 1889) Dr. W. Behrens.
Dowling, C. H., Series of Metric Tables BAO cea ee Mr. Crisp.

The Rev. Henry Armstrong Hall said that he had brought for ex-
hibition a preparation which he thought would be found of interest. In
January of the present year Dr. Bullock—who was at the meeting that

PROCEEDINGS OF THE SOCIETY. 849

evening—gave him a sample of urine which, when examined under the
microscope, was found to contain a particular bacillus. After the
ordinary process of preparation, and after staining by the method of
Neilson, on the eighth or ninth slide being examined, he found a bacillus
which resembled very closely in appearance Bacillus tuberculosis.
Having afterwards obtained another sample from the same source, he
found in the albuminous residue a still larger proportion of the same
bacillus ; but although it showed the same beaded appearance, and had
the same power of retaining the stain in the presence of nitric acid, he
could not, of course, say yet that it was B. tuberculosis, though it very
strongly resembled it in appearance. He believed that it was very rare
to find it in this way in the urine, though it was said that in some cases
of tubercular disease of the kidney it was to be found. The patient
from whom the specimens came was alive, and the case was looked upon
as one of great interest by Dr. Bullock, and if it subsequently proved
that this bacillus was really identical with B. tuberculosis, it would show
the importance of its being looked for in similar cases. The preparation
shown under the Microscope in the room would be seen to be full of the
bacilli, lying mostly in groups.

Dr. Bullock said the case to which Mr. Hall had referred had been
under his care for some time, and had presented considerable difficulty
in diagnosis, Several opinions had been taken upon it; and the
question was whether it was a case of calculus in the kidney, or whether
it was one of tuberculosis. This was obviously of great importance to
determine, since if it was calculus it would be remediable by operation,
whereas if the case was one of tuberculosis nothing could be done.
After seeing the bacillus, and considering the specific gravity of the
water, he was inclined to think that there was tuberculosis.

Mr. G. C. Karop said it was well known that tuberculosis of the
kidney could be detected by the examination of the urine, the presence
of bacilli having been observed since about 1882. The morphological
characters of bacilli were, however, so very variable, that it was hardly
safe to rely simply upon the appearance they presented. He would
not, of course, venture to say that those which were obtained in this
case were not Bacillus tuberculosis; but he should not like it to be
thought that this method of examination in suspected cases. of this
disease was uncommon or usually neglected.

A Fellow asked if there had been any attempt made to cultivate the
bacillus ?

Mr. Hall said that this had not yet been done, though it was in con-
templation. He had shown it to Prof. Crookshank, and though he very
properly declined to commit himself to any opinion at present as to what
specific form it was, he proposed to follow up the matter by cultivation,
and eventually to test it by inoculation.

Dr. Hebb inquired if Dr. Bullock would state the age of the patient,
also how long the case had been under treatment; whether there was
any tubercular disease of the lungs, or any in the family history ?

Dr. Bullock said that the patient was twenty-one years of age, and the
symptoms were of about 45 years’ duration. The first complaint was
of pain in the right kidney, and then for a long-continued period there
was pain in the left kidney. He found there was lithic acid present in
the urine, and there had been some symptoms of stone in the bladder,
as well as several symptoms of stone in the kidney; but at present

1889. 3.N

850 PROCEEDINGS OF THE SOCIETY.

there was the very low specific gravity of 1:0004, though some time ago
it had been 1:009. There seemed no trace of tubercular disease of the
lungs, and there was none in the family history, except possibly in one
sister.

Mr. J. D. Hardy exhibited and described a little apparatus which
he had devised for the purpose of photographing an object under the
Microscope without having to alter the position of the instrument in
any way. It was, in some respects, the same as one which he exhibited
at the Quekett Club about three years ago; but whereas that one was made
of metal, and was found to be too heavy, the one before them was made
of wood, and its weight was only about 1 oz., the cost being nothing at
all beyond the trouble of making it. He thought that its simplicity and
lightness would hardly fail to recommend it, especially as most of the
commercial instruments of that sort were evidently designed by those
who did not understand the requirements of the case. Having described
the modus operandi, and stated that with the ordinary Ilford plate the
exposure required with a 1/4 in. objective was about four minutes, he
handed round some specimens of the photographs taken by the apparatus.

Messrs. Watson and Son exhibited and described a new pattern
microscope for students (the Edinburgh Student’s Microscope), and a
student’s petrological Microscope, made upon the same lines. Also a
small box for holding slides, which presented some features of novelty,
and for which a provisional patent had been obtained by Mr. Moseley,
its inventor. The slides were held in flat trays, in the usual way, but
they were so arranged that upon opening the front of the box the trays
were drawn forward, so as to form a series of layers overlapping suffi-
ciently to expose the labels at the front end of each row, and enabling
the position of any particular slide to be seen without the necessity for
removing the trays in search of it.

Mr. Crisp said this seemed to be a real novelty in cabinets, and until
he saw it he certainly had thought they must have got to the end of
anything new in the way of putting objects into cabinets.

The President said the Fellows present should all take a look at the
box, as it was a model of ingenuity, and met a want which all must have
frequently felt.

Mr. Crisp said they had from time to time commented unfavourably
upon the late Mr. C. Fasoldt, in connection with his claim to have seen
lines 250,000 to the inch. He had received a copy of an obituary
notice of Mr. Fasoldt, written by Prof. Rogers, which dealt with the
deceased’s work, and accorded him a high measure of praise for what
he had done, and, under those circumstances, he thought it would be
proper to read it now, and to publish it in extenso in the next number of
the ‘ Journal’ (supra, p. 829).

Mr. Crisp called attention to a statement published by M. Pelletan,
on the authority of Dr. Eyrich, of Mannheim, to the effect that
Dr. R. Zeiss had produced a 1/12 in. immersion objective with a
numerical aperture of 1:60, using monobromide of naphthaline. This
was higher than anything which had hitherto been accomplished ; but

PROCEEDINGS OF THE SOCIETY. 851

the use of such objectives was likely to be restricted, owing to the price,
which was 10,000 fr. or 4001.

Mr. T. Powell, in reply to a question as to the possibility of pro-
ducing such an aperture, said it would be quite possible to make it with
such a medium as the immersion fluid named, that was, of course,
supposing its refractive index was as high as 1-6.

Mr. Ingpen said that the refractive index of this medium was 1°8.

Mr. Crisp said that it would be remembered that some time ago an
extraordinary description was read at one of their meetings from the
Proceedings of the American Association for the Advancement of
Science, a society having the same object as our British Association,
in which it was proposed to convert a Microscope into a microtome by
placing the imbedded substance in the lower end of the tube and
cutting sections by means of a blade fitted to move upon the stage-plate,
the material being moved forward by the action of the fine-adjustment.
He had now brought the apparatus described for exhibition, as it might
well be thought that the original account was written as a joke, and
that it could not be seriously put forward. Having fitted up the con-
trivance in the manner described, he showed the way in which it was
proposed to be used.

Mr. Karop and Mr. J. Mayall, jun., made several suggestions as to
possible conversions of a Microscope to domestic and other uses if it
was not considered necessary to confine it to its original purpose.

Mr. J. Mayall, jun., described the various Microscopes and acces-
sories which he had examined at the Paris Exhibition, pointing out that
whereas at former international exhibitions most of the best makers in
England, America, and other countries, were exhibitors, on this last occa-
sion they had been rather conspicuous by their absence. He had seen very
little that was new in the matter of design. The French opticians were
fairly well represented as to numbers, but the instruments they exhibited
were for the most part of the old, not to say antiquated types. Where,
perchance, one or another had ventured to add an adjustable substage
to his Microscope, this had been done in what English microscopists
would regard as a clumsy and ineffective way, by no means up to the
standard that would be required in England. When French opticians
were questioned why they did not produce Microscopes more suitable
for the critical microscopy of the present day, they replied that there
was no amateur scientific class in France as in England, and that they
were therefore obliged to restrict themselves to what was suitable for
medical use; that medical students there used the Microscopes very
roughly, and the instruments had consequently to be made strong and
heavy, without much regard to delicacy of adjustment. Comparing
the French exhibits with those of previous exhibitions, he thought the
advance shown was principally in the direction of finer lacquering or
nickelizing, or more elaborate upholstery. Here and there ingenuity
was shown in packing a portable Microscope in a very small space, or
in making a large number of appliances fit into dainty-looking velvet-
lined partitions, so that the eye at least was pleased; but the solid
merits of construction and design, as evidenced by good mechanism
giving the microscopist perfect command of all necessary adjustments,

852 PROCEEDINGS OF THE SOCIETY.

seemed to be almost wholly neglected. Some little attention had been
given to photo-micrographic combinations of apparatus; but here again
the main essentials of steadimess and facility of adjustment were lost
sight of, or were so encumbered with useless fittings that one could only
view them as eccentricities of ingenuity. The German opticians were
wholly absent, as also were the American. The English were represented
by Ross & Cv., Dallmeyer, Pillischer, and Watson & Sons. The Grand
Prix had been awarded to Ross & Co., presumably for the variety and
importance of their exhibits, which included a new pancratic eyepiece
for the telescope, doing away with the necessity of altering the focal
adjustment, sundry improved photographic lenses and cameras, and
Wenham’s radial Microscope. Of course the award of the Grand Prix
did not commend itself to the less successful competitors, and some dis-
satisfaction was expressed at the appointment of M. Alfred Nachet as
the microscopical expert to advise with the jury. It seemed to him,
however, that no more competent man was known in Paris than M. Nachet,
and it was a matter of course that the expert should be a Frenchman.
He (Mr. Mayall) had endeavoured to set aside all prejudice, and to
estimate the quality of the exhibits impartially, and he was bound to say
the award of the Grand Prix to Ross & Co. seemed to him equitable,
for their apparatus, viewed as a whole, was the most important of the.
optical exhibits. He could have wished there had been more of com-
mendable novelty in the Wenham radial Microscope, as exhibited in its
latest form; still, when compared with the other Microscopes in the
exhibition, it had really no worthy rival. He thought it much to be
regretted that Messrs. Powell and Lealand did not exhibit; had they
done so they would easily have carried the palm for Microscopes. There
appeared to have been a great many unnecessary difficulties thrown in
the way of the English exhibitors. They were shunted up into the
galleries, where their exhibits were practically unseen, and all sorts of
vexatious conditions were imposed at the outset that dismayed the bulk
of intending exhibitors. In the face of these unfavourable conditions he
could well understand the reluctance of Messrs. Powell and Lealand,
Beck, and Swift to compete, especially with the experience they had of
the difficulties of being properly represented at the Paris Exhibition of
1878.

The President said they must all feel greatly indebted to Mr. Mayall
for the trouble he had taken in explaining what he had seen as well as
in looking at the exhibits for this purpose.

The President announced that the Conversazione would take place
on November 27th.

The following Instruments, Objects, &c., were exhibited :—

Mr. Crisp :—Hart’s Microtome Microscope.

Rey. H. A. Hall :—Bacillus from Urine.

Mr. J. D. Hardy :—Photomicrographic Apparatus.

Messrs. Watson and Sons :—(1) Edinburgh Students’ Microscopes,
(2) Moseley’s Slide Cabinet.

New Fellows:—The following were elected Ordinary Fellows :—
Mr. H. C. B. Chamberlin, and the Rey. P. W. Hart-Smith, M.A.

€° 853 )

INDE X.

———

° A.

Abbe, E., Effect of Illumination, &c.; 847.

—, 1/10 in Apochromatic Objective of
N.A. 1°63, 805.

——, Notes on the Effect of Illumination
by means of Wide-angled Cones of
Light, 721.

Abbe Achromatic Condenser, 609.

Abietinez, Fruit-scales of, 407.

scales of, 88.

— Polymorphism of the Leaves of, 245,

Abranchiate Lamellibranchiata, 740.

Acalephe, Eyes of, 532.

Acanthocephala, Female Genital Ducts,
519.

Acarid, New, 638.

Acarina, Marine, Coasts of France, 509.

, of Wimereux, 211.

Acephala, Edge of Mantle of, 198.

Achenes of Coreopsis, 778.

— of the Rose, 778.

Achorion Schonleinii, Culture of, 296.

Acids, Effect of dilute, on Alge, 418.

Acqua, C., Formation of Calcium oxalate
in Plants, 774.

Acroblaste, 421.

Actiniz, British, Revision of, 647.

Actinian, Remarkable, 530.

Actiniaria, Two new Types of, 70.

Actinida, North Atlantic, 230.

Actinomyces, Staining, 150.

Actinospheerium eichhorni, Development
of, 400.

Actinozoa, Occasional Presence of a Mouth
and Anus in, 761.

Adametz, L., Saccharomyces lactis, 426.

Adams’s large Projection and Compound
Microscope, 438.

Address, President’s, 169.

Adelphotaxy, 192.

Adenoma, Staining differences in resting
and active nuclei i in, 712.

Aderhold, R., Forces which determine the
Movements in the Lower Organisms,

Adjustable Safety-stage,.121.
Adlerz, G., Morphology and Larvee of
Pantopoda, 509,

1889,

Hygroscopic Movements in the Cone-"

Aducco, V., Red ,Colouring Matter of
Eustrongylus gigas, 225.

Adulteration and Microscope, 136.

Aegyria oliva, 74.

JHolidiide, Genera of, 374.

Aeolosoma tenebrarum, Green Cells in
Integument of, 515.

Afghan Delimitation Commission, Zoology
of, 626.

Africa, East, Fresh-water Fauna, 494, 733.

African Tripoli, Diatoms of, 683.

Agalma Clausi, 393

Agamic Multiplication of Lower Metazoa,
753.

Agardh, J. G., Apical cell of Lomentaria
and Champia, 556.

Agaricus olearius, Phosphorescence of, 564.

Ahrens’ (C. D.) Giant Microscope, 273.

modification of Delezenne’s Polarizer,
276.

— Polarizing Binocular

85

Microscope,

Air, Bacteriological Examination of, 843.

, Number of Micro-organisms in, 603.

Aitchison, J. E. T., Zoology of Afghan
Delimitation Commission, 626.

Albumen, Decomposition of, in the absence
of free oxygen, 92.

Albuminoids, Influence of Oxygen in
Decomposition of, 783.

» Products of the Decomposition of,
in the absence of free oxygen, 253.

Albuminous Composition of Cell-walls,
Growth of, 402.

Alburnum, Conduction of Fluids through,
90.

Alcoholic Fermentation of Milk, 783,

Alder, Fungus-parasites of, 680.

Aleppo Pine, Relation of the Bacilli of, to
the living tissues, 797. ;

Aleurone-grains, 81.

and Hydroleucites, 239.

Algee, fresh-water, preparations of, 139,
140.

See Contents, xxvii.
Algophaga pyriformis, 106.
Ali-Cohen, C. H., Movements of Micro-
cocci, 795.
Alimentary Canal of Larval Lamellicorns,
504.
30

854

Almquist, S., Nectarial Scales of Ranun-
culus, 662.

, Production of Honey in Convallaria,
650.

Alpheus, development of compound eye of,
382.

Alpine Climate, Influence of, on Vegeta-
tion, 414.

Alternation of Generations in Salpa and
Pyrosoma, 47.

Aluminium in Vascular Cryptogams, 551.

Amann, J., Leptotrichic Acid, 553.

, Mycose on the Sporange of Mosses,

565.

, Preparation of Muscineee, 301.

Amans, P. C., Organs of Aquatic Loco-
motion, 35.

Amateur, 695.

, Microscope Stand and some of its
aecessories, 805.

Amateurs, Microscopical Work for, 136.
Ambronn, H., Optical Properties of the
Cuticle and Suberized Membranes, 78.

American “ Bitter-rot,” 563.

Rotifera, 523.

Society of Microscopists, 136, 831

Amnion and Pro-amnion in Chick, 726.

Ameebocytes of Crustacea, 54.

Amorphophallus Rivieri, Fertilization of,
411.

Amphibia, Division
corpuscles in, 191.

Amphibian Blastopore, Fate of, 727.

Eggs, Solvent for the Gelatinous
Envelope, of, 138.

Amphibians, Development
Nervous System of, 188.

, The Species of Distomum in, 521.

Amphioxus lanceolatus, Structure of, 363.

, Nervous System of, 36.

, Peripheral Nervous System of, 625.

Amphipoda, British, 511, 639.

— ‘Challenger,’ 383.

——, Development of, 510.

, Indian, 53.

Amphiptyches, Nervous System of, 522.

Amphiura, New Parasite of, 54.

Amthor, C., Saccharomyces apiculatus, 98.

Anatifer and Pollicipes, 'Tegumentary
Coverings of, 513.

Ancylus fluviatilis, Mouth-parts of, 197.

Anderson, H. H., Anoplophrya aeoloso-
matis, 535.

—, R. J., Panoramic Arrangement for
the Microscope, 799.

, §., Development of the Vascular
bundles of Monocotyledons, 656.

Andersson, O. F., Genetic Connection of
Draparnaldia glomerata and Palmella
uveeformis, 95.

Andrews, E. A., Reproductive Organ of
Phascolosoma Gouldii, 518.

Angelopsis, 648.

of Red Blood-

of Central

in the Phisem of, 405.

INDEX.

Angiosperms, Mode of Union of the Stem
and Root in, 84:

Annelida. See Contents, xvi.

Annelidan Affinities in Ontogeny of
Vertebrate Nervous System, 192.

Annual Plants, Development of, 668, 784

Anomura of the ‘ Challenger,’ 382.

Anoplophrya aeolosomatis, 535.

Antherids of Floridez, 674.

Antherozoids of Characeee, 417.

of Ferns, 552.

—— of Fucacez, 675.

of Hepaticee and Mosses, 554.

of Vascular Cryptogams, 785.

Anthers of Cycadez, Opening of, 86.

Anthocyan, Change in Colour of Leaves
containing, 404.

Anthozoon, New, 393.

Anthrax, Antagonism of the Bacillus of
Blue Pus and, 798.

Antipatharia, New Type of Dimorphism
found in, 764.

Ants, Examining, for Intestinal Parasitic
Infusoria, 461.

——., Observations on, 49.

— , White, Holotrichous Infusoria para-
sitic in, 399.

Aperture Table, 292, 454.

Aplysia, Anatomy of, 199.

Aplysize, Hermaphroditism of, 373.

, Reproductive Organs of, 628.

Apochromatie Condenser, Powell and Lea-
land’s, 125.

—— Objective, 1/10 in. of N.A. 1°63, 805.

stolen, 805.

Apocynacee, Structure of, 660.

Apospory in Pteris aquilina, 256.

Apotheces of Lichens, Origin and Devel-
opment of, 262.

Apple, Mildew of, 563.

Applegarth, E. C., Fate of Amphibian

- Blastopore, 727.

Apstein, C., Structure and Function of
Spinning Glands of Araneida, 637.

Apus cancriformis, Nyctotherus in Blood
of, 75.

Aquatic Locomotion, Organs of, 39.

—— Plants, Mechanical System in the
Roots of, 659.

Arachnida. See Contents, xv.

Ayraneida, Brain of, 211.

——, Siructure and Function of Spinning
Glands of, 637.

Araneina, Malpighian Tubes and “ Hepatic
Cells” of, 746.

Arcangeli, G., Composition of Chlorophyll,
tds

——, Flowering of Euryale ferox, 250.

——, Germination of the Seeds of Huryale
ferox, 250.

——, Kefir, 99.

, Panic Fermentation, 253.

¢ | ——-, Phosphorescence of Pleurotus ole-
Angiosperms, Development of Sieve-plates |

arius, 426.

_ ——, Seed of Victoria, 663,

INDEX,

Arcangeli, G., Seeds of Nympheacese, 407.

, Trophilegic Function of Leaves, 670.

Arenaceous Polyzoon, Anatomy of, 499.

Argulus foliaceus, 383.

Arion empiricorum, Fertilization in, 372.

Aristolochiaceze, Comparative Anatomy of,
660.

Arloing, —., Apparatus for the Bacterio-
logical Examination of Water, 605.

Arthropoda. See Contents, xiii.

Artistic Photomicrography attained, 698.

Ascaris marginata, Maturation and Ferti-
lization of Ova in, 223.

megalocephala, Fertilization
Segmentation in, 220.

Ascomycetes, Eremothecium, a new genus
of, 425.

——,, Penicilliopsis, a new genus of, 424.

Asexual Reproduction of Microstoma, 388.

Askenasy, E., Algz of the ‘Gazelle’ Ex-
pedition, 555.

Askenasya polymorpha, 418.

Asparagin in Tubers of the Dahlia, 81.

Assimilation, Chemical process in, 92. ~

Astari, A., Nuclearia delicatula, 770.

Asterias, Development of Calcareous Plates
of, 61.

Asterovidea of the Voyage of the ‘ Chal-
lenger,’ 645. ;

, Saccular Diverticula of, 761.

Astley, W., Production and Preservation
of Saccharine Crystals, 835.

Astrorhizidee, New Type of, 400.

Atax ypsilophorus and A. Bonzi, Anatomy
of, 746.

Athorybia, New, 532.

Atkinson, G. F., Phosphorescent Mush-
room, 565.

Atlantic, North, Actinida, 230.

Atmospheric Germs, Methods for ascer-
taining the Number of, 158.

Atwell, CU. B., Conjugation of Spirogyra,
786.

Aulastomum, Polar Body Formation in,
759.

Australia and New Zealand, Algee of, 97.

Australian Earthworms, 515.

Hydroida, New or rare, 71.

—— Mollusea, Anatomy and Life-history
of, 626.

Auxospore of Terpsinoé, 794.

Avrainvillea, 558.

Axis-cylinders and Nerve-cells. Demon-
strating Transverse Striations in, 297.

Azolla filiculoides, 417.

and

B.

Babes, V., Migrations of Pentastomum
denticulatum in Cattle, 212.

Baccarini, P., Coniothyrium diplodella,
425.

Bacillar Tumours of the Olive, 546.

on Pinus halepensis, 243, 546.

Bacilli, Cholera, Flagella of, 571.

855

Bacilli of Rhinoscleroma, Staining, 307.

of the Aleppo Pine, Relation of, to
the living tissues, 797.

——,, Staining Flagella of, 837.

‘ Tubercle, on Slides, 602.

Bacillus Anthracis, Spore-formation in,
429.

—— — , Variability of, 796.

——., Cholera, 797.

from Urine, 848.

muralis and Glaucothrix gracillima,

Relationship of, 103.

and Grotto-Schizophycesx, 428.

—— murisepticus pleomorphus, a new
pathogenic Schizomycete, 570.

——, New Pyogenetic, 684.

of Blue Pus and Anthrax, Antago-
nism of, 798.

—— of Glanders, Staining, 468.

of Leprosy, 568.

of Typhoid Fever, Spore-formation

in, 269.

pneumoniz, Staining the Capsule of,
601.

——.,, Tubercle, New Bovine, 796.

—, —., New method for staining, 713.

——, ——, Rapid Method of staining in
liquids and in tissues, 712.

Tuberculi, New Rapid Process for

Staining, 468.

tuberculosis, Cultivation of, on Po-
tato, 598.

—— —— in Sputum, Simple and rapid
method of Staining, 713.

, Varieties of Koch’s Comma, 269.

Bacteria, Cholera, Method for Distinguish-
ing and Isolating, 150.

5 , Resistance of to Heat and
Drying, 270.

——, Ferment from putrefactive, 104.

, Method of using with ease Objec-
tives of shortest working distance in the
clinical study of, 287.

——, Microscopical Examination of Urine
for, 313.

, Number of, in Contents of Gastro-

enteric Tube of some Animals, 683.

, Nutritive Media for the Cultivation
of, 456.

— of Fodder and Seeds, 268.

of Tubercles of Papilionacess, 430.

——,, Pleomorphism of, 795.

——, Purple, and their relation to Light,
105,

——, Sulphur, Morphology and Physics
logy of, 567.

which produce Sulphuretted Hydro-
gen, 567.

Bacteriological Purposes, Simple Appa-
ratus for Injecting Fluids for, 308.

Technique, 708.

Bacteriology of Snow, 572.

, Photomicrographic Atlas of, 107.

Bacterium Balbianii, 104.

——,, Pathogenic, found in Tetanus, 105.

302

856

Baker’s (C.) Portable Medical Microscope,
161.

Balbiani, E. G., Entophytes in Myriopods,
681.

, Merotomy of Ciliated Infusoria, 397.

Bale, W. M., New or rare Australian
Hydroida, 71.

Ballowitz, E., Structure of Spermatozoa,
36.

Balsam Bottles, 842.

Mounts, A beautiful and durable

Cement for ringing, 309.

, Cement (“ inside”) for, 309.

——, Preparing and Mounting Insects in,
600.

Bandler, —., Development of Pathogenic
Microbes on Media previously exhausted
by other Micro-organisms, 458.

Bangia, Colouring-matter of, 418.

Baranski, A., Staining Actinomyces, 150.

Barbacei, O., Phenomena of Indirect
Nuclear Fission in Investing Epithelia,
728.

Barbaglia, G. A., Oil of Bay-leaves, 405

Barber, C. A., Bulb of Laminaria bulbosa,
596.

Barclay, A., Czeoma smilacinis, 791.

, Himalayan Uredinez, 790.

Bark, Influence of Light on the Develop-
ment of, 549.

Barnsby, D., Cultivation of Bacillus tuber-
culosis on Potato, 598.

Bary’s (A. de) Microscopical Slides, 784

, Saprolegnies, 99.

Bastelberger, —., Uses of Photomicro-
graphy, 404.

Bastia, Two Infusorians from, 398.

Bateson, W., Senses and Habits of Crus-
tacea, 748.

, Variations of Cardium edule, 735.

Batrachian Larve, Epithelial Glands in,
190.

Baumgarten’s Triple Staining Method,
149)

Bausch and Lomb Optical Co., Adjustable
Hemispherical Illuminator, 126.

Bay-leaves, Oil of, 405.

Beard, J., Annelidan Affinities in Onto-
geny of Vertebrate Nervous System,
192.

, Early Development of Lepidosteus
osseus, 622.

Beck, C., The Construction of Photo-
graphic Lenses, 276.

, G. R. v., Poroptyche, a new genus of

Polyporeze, 565.

, J. D., A beautiful and durable Ce-
ment for ringing Balsam Mounts, 309.

; , A Slide of Hints and Sugges-
tions, 708.

Beddard, F. E., Anatomy and Histology
of Phreoryctes, 755.

Coccidium infesting Pericheta, 76.

, Green Cells in Intezgument of Acolo-

soma tenebrarum, 515.

INDEX.

Beddard, F. E., Marine Oligocheta of
Plymouth, 515.

——, Notes on Oligocheta, 754.

, Oligochetous Fauna of New Zea-

land, 754.

, Origin of Malpighian Tubules in
Arthropoda, 742.

——., Reproductive Organs of Eudrilus, 58.

, Structure of Clitellio, 387.

—, of Graafian Follicle in Didel-
phys, 622.
—, of Urocheta and Dichogaster,

and Nephridia of Karthworms, 218.
——, Three new Species of Harthworms,

oT.

Bedot, M., Agalma Clausi, 393.

, Preserving Marine Animals, 832.

Bees and Flowers, 505.

, Number of Polar Globules in Eggs

of, 634.

, Observations on, 49.

Begonia, Leaves of, 245.

Behme, T., Anatomy and Development of
Renal Apparatus of Pulmonate Gastro-
pods, 628.

Behrens, W., Apparatus
Objects, 842.

Behrens, W., A. Kossell, and P. Schieffer-
decker, The Microscope and the Methods ~
of Microscopical Research, 695.

Belajeff, W., Antherozoids of Vascular
Cryptogams, 785.

Belfanti, —., Pathogenic Bacterium found
in Tetanus, 195.

Bell, F. J., Large Starfish, 529.

Bellarminow, —., Shellac Injection for the
Vessels of the Kye, 150

, Technique of the “Corrosion” of
Celloidin Preparations, 151.

Bellonci, J., Examining the Central Ter-
mination of Optic Nerve in Vertebrata,
460. -

Benda, C., Hardening Method, 142.

, Macroscopical and microscopical pre-
parations for a new hardening process,
303.

Benecke, F., The importance of the micro-
scopical investigation of strengthening
fodder for practical agriculture, 471.

Beneden, P. J. v.. New Cestodes from
Lamna cornubica, 390.

Benedikt, —., On shellac, 309.

Benham, W. B., Anatomy of Phoronis
australis, 740.

Bennett and Murray’s Cryptogamic Botany,
415.

Benoist, L., Nutritive Media for the Cul-
tivation of Bacteria, 456.

Berger, E., Method for determining the
true Shape of Microscopie Objects,
158.

Bergh, R., Genera of Aiolidiide, 374.

Berlese, A. N., Echinobotryum
Stysanus, 788.

——, Linboulbeniaces, 789-

for Isolating

and

INDEX.

Berlese, A. N., Prolification in the Hypho-
mycetes, 789.

Bermuda Islands, Actinology of, 648.

, Marine Invertebrates of, 194.

Bertkau, P., Hermaphroditism in Gastro-
pacha, 503.

. Parasites of Spiders, 638,

Bessey, C. E., The need of making Mea-
surements in microscopical work, 454.

, Vacation Notes upon some Botanical
Laboratories, 158.

Beyendal, D., Male Copulatory Organs on
first Abdominal Appendage of some
female Crayfishes, 53.

Beyer, H., Spontaneous Movements of
Stamens and Styles, 251.

Beyerinck, M. W., Bacteria of the Tu-
bercles of Papilionaces, 430.

Bézu, Hausser and Co.’s Photomicrographic
Apparatus, 452.

Bialle de Langibauditre, —, Mounting
Diatoms, 469.

Bible, Micro-organisms of, 314.

Bidwell, W. D., A Land Title settled by
the Microscope, 471.

Bidwell Cabinet, 716.

Bielkowsky, —., Diosmose through the
Cellulose-pellicle of Phragmites com-
munis, 539.

Bigelow, R. P., Structure of the Frond of
Champia parvula, 418.

Bignoniacee, Vegetative Organs of, 410.

Billet, A., Bacterium Balbianii, 104.

Binuclearia, 259.

Biondi, D., Spermatogenesis in Man, 365,

Bipalium, Structure of, 226.

Birds’ Eggs, Colour of, 30.

, Insects supposed to be distasteful to,
633.

—,, Nerve-cells in, 494.

Bitter, H., Doctrine of Phagocytes, 267.

“ Bitter-rot,” American, 563.

Black, impregnation of tissues, 838.

Blanc, H., Tapeworms with Perforated
Joints, 225,

Blaps mortisaga, Odoriferous Glands of,
744.

Blastodermic Layers in Isopoda, 639.

Blastomyces, 786.

Blattidz, Anatomy of, 506.

Bleaching Agents, Action on Glass, 314.

Blix’s (M.) Microscopes for measuring the
radii of the curved surfaces of the Hye,
688.

Blochmann, F., Number of Polar Globules
in Fertilized and Unfertilized Eggs of
Bees, 634.

, Simple Method of freeing Frog’s
Ova, 599.

Blondel, R., Perfume of the Rose, 774.

Blood, Distinguishing Stains of Human,
158.

— of Apus cancriformis, Nyctotherus in,

eae of Dog, Nematode in, 58.

857

Blood of Vertebrates, Origin of, 725.

Blood-corpuscles in Amphibia, Division of
Red, 191,

» Red, of Adult and Larval
Lampreys, 494.

Bohm, A. A., Maturation and Fertilization
of Ovum in the Lamprey, 189.

—., Preparing Eggs of Petromyzon,
704.

—., J., Formation of Starch in the
Leaves of Sedum spectabile, 541.

Bohmig, L., Microstoma papillosum, 757.

Bokorny, T. Chemical process in Assimila-
tion, 92.

» Reduction of Silver in the living-
cell, 539.

Boldt, R., Distribution of Desmidiacez,
676.

Boletopsis, a new genus of Hymenomycetes,
792.

Bolley, H. L., Subepidermal Rusts, 791.

Bombyx, Respiration of Ova of, 635.

Bondurant, E. D., Section-fixing, 840.

Bone, Division and Degeneration of Giant-
cells of Medulla of, 729.

Bonnet, H., Parasitism of the Truffle, 788.

Bonnier, G., Development of Lichens on
the Protoneme of Mosses, 680.

» Influence of Alpine Climate on

Vegetation, 415.

» Morphology anil Systematic Position
of the Dajide, 513.

——,, Parasitic Crustacea, 512.

—,, Synthesis of Lichens, 679.

, —— of Physcia parietina, 561.

Boodle, L. A., Avrainvillea, 558.

, Spongocladia, 557.

——,, Struvea, 260.

Booth, M. A., Finishing Slides, 471.

Bordzilowski, J., Development of Berry-
like and Fleshy Fruits, 662.

Born, G., Plate Modelling Method or
Plastic Reconstruction of the Object,
144.

, Segmentation in Double Organisms,
366.

Borneo Butterflies, Habits of certain, 744.

Bornet, E., Ectocarpus, 675.

, Heterocystous Nostocacex, 103, 793.

Borragoid Inflorescence, 663.

Borzi, A., Eremothecium, a new genus of
Ascomycetes, 425.

——, Lateral Roots of Monocotyledons,
547.

——, Xerotropism in Ferns, 256.

Bostock, E., The Presidential Address [to
the Postal Microscopical Society], 455.

Botanical Microscope, Pfeffer’s, 272.

Bottle, Improved Form of the “ Wright ”
Collecting, 295.

Bourne, C. G., Pelagic Copepoda of
Plymouth, 753.

——.,, Tornaria in British Seas, 523.

Bourquelot, E., Saccharine matters of
Fungi, 677.

858

Boutan, L., Ventral Nervous Mass of
Fissurella, 496.

Bouvier, L., Nervous System of Decapod
Crustacea, 750.

Boveri, T., Fertilization and Segmentation
in Ascaris megalocephala, 220.

Bovine Tubercle Bacillus, New, 796.

Bower, F. O., Pitcher of Nepenthes, 779.

Bract in Tilia, 407.

Bracteoles of the Involucre in the Cynaro-
cephale, 778.

Bracts of the Involuere in Cichoriacez, 408.

Brady, H. B., New Type of Astrorhizide,
400.

—,, N., Illustrations of Diffraction, 701.

—,58., Ostracoda of North Atlantic and
North-western Europe, 512.

Braem, F., Formation of Statoblasts in
Plumatella, 377.

Braemer, L., New micro-chemical reagent
for Tannin, 606.

Brain of Araneida, 211.

of Peripatus, 745.

of Somomya erythrocephala, Pre-

paring, 301.

, Vertebrate, Primitive Segmentation
of, 725.

Brandes, G., Helminthological Notes, 520.

Braun, M., Tristomum elongatum, 7 58.

Brazil, Coffee-Nematode of, 518.

Brazilian Batrachia, Cystodiscus immersus
—a Myxosporidium found in the gall-
bladder of, 537.

Brefeld, O., Ustilaginez, 787.

Brick, C., Litoral Plants, 82.

Briosi, G., Mineral Substances in Leaves,
240.

Brisbane, New Species of Megalotrocha
from, 610, 613.

Brock, J., Neurology of Prosobranchiata,
372.

—, Ophiurid Fauna of Indian Archi-
pelago, 66.

——,, So-called Organ of Verrill in Cepha-
lopoda, 496.

Bromeliaceze, Anatomy of, 411.

Brongniart, C., Entomophthorez and their
use in the destruction of noxious Insects,
261.

Brook, G., Lucifer-like Decapod Larva,
751.

, Metamorphosis of British Huphau-
siidee, 752.

——, New Type of Dimorphism found in
Antipatharia, 764.

Brooks, H., Life-history of Stenopus, 752.

, Structure of Siphon and Funnel of
Nautilus Pompilius, 495.

Broom, R., Abnormal Earthworm, 387.

, Medium for mounting Starches and
Pollens, 834.

Brown, A. P., New Medium for Mounting
Pollens and Starches, 602.

—-~, F. W., A Course in Animal His-
tology, 158, 314, 471.

INDEX.

Briicke, —., On the behaviour of congo-
red with some acids and salts, 308.

Brussels, Scientific instruments at the
International Exhibition at, 136.

Bryozoa, preparing freshwater, 138.

See Contents, xiii.

Buchanan, F., Ancestral Development of
Respiratory Organs of Decapodous
Crustacea, 381.

Bud of the Tulip-tree, 245.

Buds, Protection of, in the Tropics, 86.

Buj wid, OF Method for Distinguishing and
isolating Cholera Bacteria, 150.

“ Bulblets ” of Lycopodium lucidulum, 255.

Bulloch, C., New Medium for Mounting
Pollens and Starches, 602.

Bunodes and Tealia, 763.

Birger, O., Nervous System of Nemer-
tines, 519.

Bury, H., Embryology of Echinoderms,
390.

Buscalioni, L., Intercellular Spaces in the
Tegument of the Seed of Papilionacez,
7709.

Biisgen, M., Structure and Function of the
Bladders of Utricularia, 545.

Butler, A. G., Insects supposed to be dis-
tasteful to Birds, 633.

Biitschlis (O.) ‘ Protozoa,’ 234, 397, 649,
766

——,, Structure of Protoplasm, 731.

Butterflies’ Enemies, 504.

——, Habits of certain Borneo, 744.

Butterfly, Changes of Internal Organs in
Pupa of Milkweed, 379.

Byssus of young of common Clam, 375.

C.

C., W. S., Micro-organisms of the Bible,
B14.

Cactacen, Secretion receptacles in, 656.

Ceoma smilacinis, 791.

Calanida of Finland, 215.

Calcium oxalate, Formation of, in plants,
655, 774.

, Influence of Light on, 655.

, in Plants, 774.

Calcutta, ‘ita, Podophrya from, 768.

Calves, Micro-organisms of Pneumonia of,
270.

Cambium, Periodical Activity of, in the
Roots of Trees, 549.

Camera, Kibbler’s Photomicrographie, 127.

— Lucida, Thoma’s, 119.

Camerano, L., New Species of Gordius,
225.

Cameras, Robinson’s Photomicrographic,
128.

Campbell, D. H., Clearing and Staining of
Vegetable Preparations, 306. —

——, Demonstration of Embryo-sac, 600.

——, Development of Pilularia, 254.

——, Germination of Marsilia egyptiaca,
254.

INDEX.

Campbell, D. H., Systematic Position of
the Rhizocarpes, 254.

Canary Islands, Siphonophora of, 530.

Cancer of the Cinchona, 100.

Canfield, W. B., Microscopical Examina-
tion of Urinary Sediment, 708.

Cankers in Coniferse, Pezize causing, 263.

Canu, E., New Family of Commensal
Copepods, 53.

Cape and New Zealand Species of Peri-
patus, Maturation of Ovum in, 507.

Caprella ferox, Investigation of Ova of,
599.

Capsicum, Epiderm of the Seeds of, 244.

Carbolic Acid in Mounting, 841.

Carcinoma, Staining differences in resting
and active nuclei in, 712.

Carcinus meenas, Liver of, 750.

Cardium, edule, Variations of, 735.

Carlet, G., New Mode of Closing Traches
of Insects, 205.

—,, New Organ of Hymenoptera, 205.

——., Stigmata of Hymenoptera, 500.

Carminic Acid Stain, 305.

Carnelly, T., New Method of Determining
the number of Micro-organisms in Air,
603.

Carpenter, P. H., Comatulids of Kara Sea,
227.

——, Eye of Decapod Crustaceans and
Arachnids, 742.

Carritre, J., Eyes of Mollusca, 626.

, Parasitic Trichodina, 650.

Carter, F. B., Desmids; Life-history and
Classification, 462.

—, H. J., New British Species of
Microciona, 396. __

Carter’s Genera and Species of Sponges,
List of, 397.

Caryophyllacee, Glands on the Stamens
of, O44,

Caryophyllia rugosa, 530.

Castracane, F., Antiquity of Diatoms,
266.

—, Composition of the Marine Tripolis
of the Valley of Metaurus, 102.

— , Cyclophora, 683.

— , Diatoms of African Tripoli, 683.

—, of Hot Springs, 102.

——, Reproduction and Multiplication of
Diatoms, 22.

Castration, Parasitic, of Lychnis dioica,
412.

Cattaneo, G., Amcebocytes of Crustacea,

——,, Intestine of Decapoda and its Gland,
639.

Cattle, Migrations of Pentastomum denti-
culatum in, 212.

Caulerpa, Cellulose-fibres of, 558.

Cavara, F., American “ Bitter-rot,” 563.

——, New Fungi of the Vine, 100.

, New Parasitic Fungi, 264.

Cave Animals, Factors in the Evolution
of, 191.

859

Cell, living, Reduction of Silver in, 539.

, New, 716.

— , Structure of, and Phenomena of its
Division, 366.

Cell-body and Nucleus, Relation between,
493.

—— -division, Embryonic, 624.

—— -structure, Investigation of, 459.

—— . See Contents, x.

—— -Theory, The Modern, 193.

—— -wall, Formation of, 653.

-——,, Growth of, 538, 653.
-——, Structure of, 538.

Celli, A., Internal Structure of the Plas-
modium Malariz, 651.

, Ordinary Foodstuff as Media for pro-
pagating Pathogenic Micro-organisms,
296.

Celloidin Preparations, Technique of the
“ Corrosion” of, 151.

Cells and Cement Varnishes, 470.

, Green, in Integument of Aeolosoma
tenebrarum, 515.

— , Living, Vital Processes in, 492.

— , New Formation of, 493.

, Process of Oxidation in Living,
590.

Cellulose, Iodine Reactions of, 467.

Cellulose-fibres of Caulerpa, 558.

Cement, Copal, 4/0.

for ringing Balsam Mounts, 309.

— (“inside”) for Balsam Mounts, 309.

Varnishes and Cells, 470.

Cephalopoda. See Contents, xi.

Cercaria setifera, 522.

Cercomonas intestinalis, 76.

Cerianthus, Arrangement of Tentacles in,
761.

Ce-tes, A., Micro-organisms in Paunch of
Ruminants, 651.

Cestodes, Embryology of, 389.

, New, from Lamna cornubica, 390.

Ceylon, Madrepore Corals from, 762.

Chabry, —., Monstrous Larve of Echinus,
392.

Chadwick, H., Mounting Insects in
Balsam without pressure, 708.

Cheetopeltis, 259.

Chalande, J., Spinnerets of Myriopoda,
507.

‘Challenger,’ Amphipoda, 383.

, Anomura, 382.

——, Asteroidea, 645.

» Polyzoa, 629.

——,, Siphonophora, 394,

——, Tunicata, 376.

Champia, Apical cell of, 556.

parvula, Structure of Frond of, 418.

Chapman, F., Additional note on the
Foraminifera of the London Clay, 483.

, FE. T., Carbolic Acid in Mounting,
841.

Characes. See Contents, xxvii.

Charles I. Microscope, 440.

Chaulnes’, Duc de, Microscope, 118.

860

Chauveau, A., Variability of Bacillus
anthracis, 796.

Chermes, 380.

and Phylloxera, 379.

—, Biology of Gall-producing, 506.

, Life-history of, 745.

Cherries, “‘ Tan-disease”’ of, 551.

Chestnut-trees, Disease of, 562.

Chick, Pro-amnion and Amnion in, 726.

Chionyphe, 558.

Chitin Solvents, 303.

, Experiments with, 141.

Chuit, P., Lactarius piperatus, 682.

Chlorophyll, Chemistry of, 79, 539.

, Composition of, 773.

, Formation of, by Coniferes in the

dark, 541.

in Animals, 649.

——,, Pure, 653.

Chlorophyll-bands of Spirogyra, Contrac-
tion of, 557.

-bodies of Selaginella, 93.

—— -grains, Structure of, 78.

Chlorophyllous Assimilation and Transpi-
ration, 669.

Chlorosis, 671.

Chmielewskij, W., Absorption of Water by
Leaves, 671.

— Conjugation of Nuclei in the Impreg-
nation of Fungi, 677.

Chodat, R., Lactarius piperatus, 682.

Cholera Bacilli, Flagella of, 571.

— Bacillus, 797.

— Bacteria, Method for Distinguishing
and Isolating, 150.

, Resistance of, to Heat and Dry-
ing, 270.

Cholodkovsky, N., Chermes, 380.

——, Embryology of Insects, 377.

, Life-history of Chermes, 745.

Chordariacez, Frond of, 676.

Christie, J., Esparto-grass, 784.

Christy, T., Koch and Max Wolz’s Lamp,
160.

Chromatology of British Sponges, 396.

Chromatophores of Pheosporee, 95.

Chromo-copper Light-filter, 133, 700.

Chromogenous Microbe, New Species of,
684.

Chromoleucities, 79.

Chun, ©., Amphipod Family of Scinida,
512.

— Coelenterata, 761.

——, Male of Phronima sedentaria, 753.

, Siphonophora of Canary Islands, 530.

Church, A. H., Aluminium in Vascular
Cryptogams, 551.

Chytridiacez, Biology of, 422.

— Olpidiella, a new genus of, 262.

Cichoriaceze, Bracts of the Inyolucre in,
408.

Cilia and Pseudopodia, 237.

Ciliata, Maupas’ Researches on, 534.

Circulatory System of Fishes, Injecting and
Preparing, 307.

———

INDEX.

Cirripedes, Formation and Number of
Polar Globules in, 385.

Cladocera of Hungary, 215.

Cladosporium herbarum, 563.

Clam, Byssus of young, 375.

Clark, J., Protoplasmic Movements, 78.

Clarke, J., Protoplasmie Movements and
their Relation to Oxygen Pressure,
732.

of the Visual Area in the Trilobites,
212.

Claus, C., Marine Ostracoda, 214.

, Nebaliidee and Leptostraca, 213.

——,, Organization and Phylogeny of Si-
phonophora, 764.

Cleistogamic Flowers, 412.

Cleistogamous Flowers of Tephrosia heter-
antha, 85.

Cleavage, New Phenomenon of, in Ovum
of Cephalopods, 734.

Climatal Conditions, Adaptation of Ana-
tomical Structure to, 89.

Cliona, 534.

Clione limacina, Anatomy of, 497.

Clitellio, Structure of, 387.

Clubb, J. A., Nudibranchiata of Liverpool
District, 627.

Cobb, N. A., Anatomy and Ontogeny of
Nematodes, 224.

, Examination of Nematodes, 300.

Coccidium infesting Pericheta, 76.

Cock, G. B., Microscope in the Mill, 717.

Coelenterata. See Contents, xxviii.

Ccelom and Nephridia of Paleemon serratus,
749.

, Development of, in Enchytroeides
Marioni, 387.

Coffee-Nematode of Brazil, 518.

Coleopuccinia, 564.

Cole’s (A. C.) New Slides, 714.

Colin, —., Reservoirs of Gum in Rham-
nances, 241.

Collembola and Thysanura, 208, 299.

Colman, W.S., Section Cutting and Stain-
ing, 147.

Colouring Matter of Drosera Whittakeri,
240.

—— —— of Leaves and pllomens 80.

—— —— of Mycetozoa, 792.

er RR. Red, of Eustrongylus gigas,

Colours of Flowers, Spectrum-analysis of,
403.

Comatulids of Kara Sea, 227.

Composite, Elastic Stamens of, 544.

——, Extrafloral Nectaries in, 87.

——, Sensitive Stamens in, 778.

Concarneau, New Ciliate Infusoria from,
398.

Condenser and Objective, Back of, 288.

——, Apochromatic, Powell and Lealand’s,
125.

Cone-seales of Abietinew, Hygroscopic
Movements in, 88.

INDEX.

Confervoides, Classification of, 419.

Conifers, Closing of the Bordered Pits in,
542.

—., Formation of Chlorophyll by, in the
dark, 541.

— , Ovuliferous Scale of, 777.

—, Pezize causing Cankers in, 263.

—, Stomates of, 546.

, Transfusion tissue of, 657.

Conifers, Bordered Pits of, 242.

, Influence of Exposure on the Growth
of the Bark of, 669.

Coniothyrium diplodella, 425.

Conjugation of Nuclei in the Impregnation
of Fungi, 677.

— of Spirogyra, 786.

Conyallaria, Production of Honey in, 655.

Convolyulacez, Pollen of, 406.

Cooke, M. C., New Development of
Ephelis, 562.

Copal Cement, 470.

—— Solution, Limpid, 154.

Copepod, New Parasitic, 641.

Copepoda, Parasitic, Female Generative
Organs and Oogenesis in, 753.

— , Pelagic, of Plymouth, 753.

Copepods, New Family of Commensal, 53.

——, New Pelagic, 640.

——,, Two new, parasitic on Echinoderms,

Copulatory Apparatus, Male, of Pompi-
lidze, 205

Organs, male, on first Abdominal

Appendage of some female Crayfishes,

53.

Corals, Madrepore, from Ceylon, 762.
Coreopsis, Achenes of, 778.

Cork-wings, Development of, 242, 405.
— -—— on certain Trees, Development

of, 84.

Corks in Imbedding, Substitute for, 305,
462.

Corn, Gluten in the grain of, 773.

Cornulariz, New, 230.

Correns, E. C., Extrafloral Nectaries of
Dioscorea, 543.

, Growth of the Cell-wall by Intussus-
ception in some Schizophycea, 793.

Corymbifere, Structure of the Bracts and
Bracteoles in the Involucre of, 662.

Corynites Curtissii, Development of, 264.

Costantin, J., Blastomyces, 786.

, Cladosporium herbarum, 563.

— ,, Echinobotryum and Stysanus, 788.

——, New method of recognizing small
quantities of Invertin, 607.

——, Simple Mucedinez, 422.

, Tulasnella, Prototremella,
Pachysterigma, 554.

Cotyledons, Water-pores in, 546.

Coulter, J. M., Continuity of Protoplasm
in Plants, 601.

——, §., Leaf of Taxodium, 664.

Council, Report of, 315.

Courchet, L., Chromoleucites, 79

and

861

Courmont, J., New Bovine Tubercle
Bacillus, 796.

Cover-glasses, Fixing Objects to, 308.

of Mounted Preparations,
Determining the Thickness of, 154.

Cox, C. F., Letter of Darwin to Owen,
454,

Coxal Glands of Arachnida, 210.

Crania, Modified Ectoderm in, 48,

Crayfish, Monstrosity in a, 213.

Craytishes, male Copulatory Organs on
first Abdominal Appendage of some
female, 53.

Crenacantha, 420.

Crépin, F., Odour of the Glands in Rosa,
775.

——, Ovaries and Achenes of the Rose,
778.

Crety, C., Structure of Solenophorus, 523.

Crinoids, Anatomy of, 525.

— , Morphology of, 528.

Crisp, F., Ancient Microscopes, 305.

, on Zeiss’ 1/12 immersion, 850.

Croneberg, A., Anatomy of Pseudo-
scorpions, 211.

Cronin Mystery, The Microscope in, 702.

Cross-fertilization in Hydrangea, 250.

Crotalocrinus, 228.

Crouch’s (H.), Petrological Microscope.
113.

Crustacea. See Contents, xv.

Cryptogamia. See Contents, xxvi.

Crystals, Apparatus for measuring very
minute, 277.

, Saccharine, Production and Preser-
vation of, 835.

Cuccati, J., Preparing the
Somomya erythrocephala, 301.

Cuénot, L., Lymphatic Glands of Cephalo-
pods and Decapodous Crustacea, 495.

Culpeper Microscope, 166.

Cultivation plates, Rest for, 602.

Culture Processes. See Contents, xxxiv.

Cumulative Segregation, Divergent Evolu-
tion through, 33.

Cunningham, D. D., Cholera Bacillus, 797.

, Lrritability of Mimosa, 252.

——, Ravenelia, 791.

—, Rhamphospora, a new genus of
Ustilaginez, 423.

, Stomatochytrium, a new genus of
Endophytic Protocoecacex, 565.

——, J. T., Reproduction and Develop-
ment of Teleostean Fishes, 491.

K. M., Preparation of Type-plates
and arranged Groups of Diatoms, 152.

Cunoctantha and Gastrodes, 232.

Curties, C. L., Nelson-Curties Microscope
(Large Model), 800,

Curtis, F., Development of Nail in Human
Foetus, 620.

Curvature of Growing Organs, 782.

— , Phenomena of, 92.

Cuscuta Gronovii, 410.

Cuticle, Optical Properties of, 78

Brain of

862

Cyanophyces, Classification of, 102.
Cycadez, Opening of the Anthers of, 86.
—., Pollen of, 772.

Cyclophora, 683.

Cyclops, Method of investigating, 300.

—, Morphology of, 215.

Cymbuliopsis calceola, Anatomy and His-
tology of, 734.

Cynarocephalez, Bracteoles of the Inyolucre
in, 778.

Cyperaceze, Stomates of, 545.

Cyprinoids, Development of Germinal
Layers, Notochord, and Mid-gut in, 31.

Cypris, Cysticercoids in the body-cavity
of, 322. :

Cystodiscus immersus, a Myxosporidium
found in the gall-bladder of Brazilian
Batrachia, 537.

Cystoliths in Hxostemma, 405.

Cyttaria, 424.

Czapski, 8., Compensation Ocular 6 with
1/1 micron graduation for use with
Zeiss’s apochromatic objectives, 119.

——, Determining the Thickness of Cover-
glasses of Mounted Preparations, 154.

——,, Ear (Tympanum) Microscope, 112.

D.

Daguillon, A., Polymorphism of the Leaves
of Abietinese, 245.

Dahl, F., Vision of Insects, 502.

pena Asparagin and Tyrosin in Tubers
of, 81.

Dajidz, Morphology and Systematic Posi-
tion of, 513.

Dall, W. H., Abranchiate
branchiata, 740.

, Gastropoda and Scaphopoda of the
West Indian Seas, 735.

Dallinger, Rev. W. H., Interview with,
702.

eevee robusta, Scars on the Stem of,

46.

Dammer, M., Diclinism and Hermaphyro-
ditism, 667.

pesca, P. A., Biology of Chytridiacee,
422.

——., Chlorophyll in Animals, 649.

—,, Formation of Subterranean Swellings
in Hranthis hyemalis, 247.

, Inferior Algee, 95.

—, Mode of Union of the Stem and Root
in Angiosperms, 84.

—,, Sexuality among the Lower Alex,
260.

Daniel, L., Bracteoles of the Inyolucre in
the Cynarocephale, 778.

, Comparative Anatomy of the Bracts

of the Involucre in Cichoriacez, 408.

. Structure of the Bracts and Bract-
pols in the Inyolucre of Corymbiferz,

Danielssen, D. C., North Atlantic Acti-
nida, 230.

Lamelli-

INDEX.

Darkschewitsch, L., Method for keeping
Serial Sections in order during manipu-
lation, 710.

Darwin, Letter of, to Owen, 454.

Darwinism, 619.

Davidoff, M. v., Developmental History
of Distaplia magnilarva, 498..

Davidson’s (T'.) Recent Brachiopoda, 202.

Davies, W. Z., Copal Cement, 470.

Davis, G. E., Practical Microscopy, 294.

Dawson, W., Nematophyton, 560.

Death’s-head Moth, Parthenogenesis of,
208.

Deby, J., Bibliotheca Debyana, 702.

——, Description of a New Dipterous
Insect, Psamathiomya pectinata, 180.

, “On a new Dipterous Insect, Psa-

mathiomya pectinata,”’ 322.

, Structure of Diatom-valves, 101.

Decapoda, Intestine of, and its Gland, 639.

Deés, H. D. de, Cladocera of Hungary,
215.

Degagny, C., Nuclear Origin of Proto-
plasm, 239

Deichler, C., Parasitic Protozoa in Hoop-
ing Cough, 651.

Delagia Cheetopteri, 377.

Delamarea, a new genus of Pheogsporee,
676.

De la Rue, Warren, Death of, 473.

Delezenne’s Polarizer, Ahrens’ Modifica-
tion of, 276.

Delpino, F., Ovuliferous Scales of Coniferee,
lide

, Tubercles on the Roots of Galega
officinalis, 546.

Demarbaix, H., Division and Degenera-
tion of Giant-cells of Medulla of Bone,
729.

Dematiex, Haplobasidion, A new genus of,
682.

Dendy, A., Anatomy of an Arenaceous
Polyzoon, 499.

— List of Mr. Carter’s Genera and
Species of Sponges, 397.

——, Sponges from the Gulf of Manaar,
396

, Stelospongus flabelliformis, 233.

Denmark, Myxomycetes of, 682.

Dennert, E., Anatomy and Chemistry of
Petals, 542.

——,, Protoplasm considered as a Ferment
Organism, 107.

Dentalium, Microscopic Anatomy of, 737.

Desert Plants, Comparative Anatomy of, 82.

Desmarestia aculeata, 675.

Desmidiaceze, Distribution of, 676.

, New Genus of, 420. :

Desmids from Massachusetts, U.S.A., List
of, 16.

, Variation in, 557. ;

Desmopterus papilio, Systematic Position
of, 734. ;

Detlefsen, H., Absorption of Light in assi-
inilating leaves, 412.

INDEX.

Detmers, H. J., American and European
Microscopes, 276, 455.

——,, Photography with High-powers by
Lamplight, 283.

Devaux, H., Exchange of Gases in Sub-
merged Plants, 670.

——,, Modification in the Roots of Grasses
growing in Water, 666.

Development. See Embryology in Con-
tents, vii.

Dewitz, H., Structure of Silurian Cephalo-
pods, 369.

.J., Slide-rest for the Manipulation
of Serial Sections, 840.

Dextrin Mucilage for Imbedding, 836.

Diagrams of Microscopical Objects, 605.

Diatom-beds of the Yellowstone, 794.

-valves, Structure of, 101.

Diatomaceous Material, Clearing recent,
302.

Diatoms, Antiquity of, 266.

, Collecting, 137.

. Fossil Marine, 566.

, Mediterranean, 427.

, Mounting, 469, 840.

, Movements of, 566, 793.

of African Tripoli, 683.

of Hot Springs, 102.

I

|

ranged Groups of, 152.

, Preparing and Mounting, 469, 834.

—,, Reproduction and Multiplication of,

Dichogamy, 548.

Dichogaster, Structure of, 218.

Dick’s (A.) Patent Petrological Micro-
scope, 432.

Diclinism and Hermaphroditism, 667.

Dicotyledons, Petiole of, 408.
, Primary Cortex in, 658.
Dicranochete, a new genus of Protococ-
eaceze, 101. f
Dideiphys, Structure of Graafian Follicle
in, 622.

Dietel, P., Germination of Teleutospores,
678.

——., Heterospory of Gymnosporangium,
563

bo

—, New Melampsora, 266.

——, Puccinia vexans, 681.

Dietz, S., Influence of the Substratum on
the Growth of Plants, 90.

Diffraction, Illustrations of, 701.

Images, A means for the detection of

spurious, 612.

Theory, 806.

Digestion in Hydra, 395.

Dimorphism of the Flowers of the Horse-
chestnut, 85.

Dinard, Polycheta of, 55.

Dineur, E., Simple and rapid method of
Staining Bacillus tuberculosis in sputum,
713.

Dingler, H., Mechanical Structure of
Floating-organs, 243.

, Preparation of Type-plates and ar-

863

Dingler, H., Floating Organs, 779.

Dino-Flagellata, 399.

Dinophilus, Anatomy of, 758.

Dionisio, I, Apparatus for fixing down
Series of Sectious, 839.

Dioscorea, Extrafloral Nectaries of, 543.

Dioscoreaceze, Anatomy of, 660.

Diosmose through the Cellulose-pellicle of
Phragmites communis, 539.

Dippel, L., Apochromaties and Compensa-
tion Eye-pieces, 119.

Dipteron, A Spinning, 506.

Discopus Synapte, Parasitic Rotifer, 60.

Diseases of the Vine, 100.

Dissecting Microscope, Binocular, 275.

, Leitz’s large, 275.

Distaplia magnilarva, Developmental His-
tory of, 498.

Distomum in Amphibians, The Species of,
O21,

Dixon, G. Y. and A. E., Bunodes and
Tealia, 763.

Dog, Development of Placenta in, 726.

» Nematode in Blood of, 58.

Dogiel, A. S., Impregnating Tissues by
means of Methylin-blue, 838.

Dor, L., Method of rapidly staining the
bacilli of tuberculosis and leprosy, 308.
Douliot, H., Intluence of Light on the

Development of Bark, 549.
, Origin of Rootlets, 664.
, Researches on the Periderm, 406.
Dowdeswell, G. F., New Species of Chro-
mogenous Microbe, 684.
Draparnaldia glomerata and Palmella
uveformis, Genetic Connection of, 95.
Dreyer, F., Structure of Pylomata of Pro-
tista, 238.

—, of Rhizopod Shells, 768.

Dreyfus, L., Biology of Gall-producing
Species of Chermes, 506.

, Chermes and Phylloxera, 379.

, Life-history of Chermes, 745.

Drogoul, —., Process of Ossification, 367.

Drosera Whittakeri, Colouring Matter of,
240.

Dry Mounts, 309.

Drying, Prevention of Cultivations from,
459

Dubois, R., Influence of Light on Pholas
dactylus, 39.

, Luminous Phenomena

dactylus, 736.

, Mounting Fish-scales, 832.

* Due de Chaulnes’” Microscope, 442.

Dufour, L., Review of works relating to
Methods of Technique published in
1888-1889.

Dugong, Placentation of, 726.

Duncan, A.W., Microscopical Examination
of Food for Adulteration, 844.

Dupetit, G., Toxic Principles of Fungi,
421.

Dyck, F. C. van, Binocular Dissecting
Microscope, 275.

in Pholas

864
E.
Ear, Human, Pathogenic Fungus from
787.

——, (Tympanum) Microscope, Czapski’s,
112.

Earthworm, Abnormal, 387.

——,, Formation of Spores of Gregarine of,
536.

—, Genital and Segmental Organs of,
57.

—.,, New, 220.

Earthworms, Australian, 515.

, Nephridia of, 218.

—, Three new Species of, 57.

Eberdt, O., Palisade-parenchyme, 82, 241.

Ebner, Vv. v., Protovertebre and the Seg-
mentation of the Vertebral Column, 302,

Ecdysis of Spiders, 380.

Echinobotryum, 788.

Echinoconid, New, 67.

Echinodermata. See Contents, xviii.

Echinoderms, Two new Copepods para-
sitic on, d+.

Echinus, Monstrous Larve of, 392.

—— Spines, Preparing Sections of, 707.

Ectocarpus, 679.

Ectoderm, Modified, in Crania and Lin-
gula, 48.

Edinburgh Student’s Microscope, 802, 850.

Edwards, C. L., Embryology of Muelleria
Agassizil, 760.

Edwardsia-stage in Free-swimming Em-
bryos of a Hexactinian. 763.

Egg ‘of Melolontha vulgaris, 506.

— of Musca vomitoria, Development in,
505.

Eggs, Amphibian, Solvent for the Gela-
tinous Envelope of, 138.

——,, Colour of Birds’, 30.

of Bees, Number of Polar Globules
in, 634.

— of Insects, Formation and Fate of
Polar Globules in, 502.

—— of Petromyzon, preparing, 704.

Ehlers, E., Delagia Cheetopteri, 377.

Eidam, E., Rhizoctonia, 681.

Eimer, G. HL AME Markings of Mammals,
30.

——,, Origin of Species, 31.

Elzomyces, a new type of Fungi, 561.

Elaphomycetes and Tuberacez, 679.

Elastic fibres, reaction of, with Silver
Nitrate, 137.

Elder, Development of the Endocarp in,

244.

Electric Lighting applied to Micrography
and Photomicrography, Recent Improve-
ments in, 696.

Electricity, Application of, to Microscopy,

277.

Eliot, W. G., Trimorphism of Oxalis, 667.
Embryo of Umbelliferz, 244.

——,, Study of a Human, 362.

Embryo- sac, Demonstration of, 600.

INDEX.

Embryology of Cestodes, 389.

of Echinoderms, 390.

— of Insects, 377.

See Contents, vii.

Embryonic Abdominal Appendages in
Insects, Structure and Phylogenetic
Significance of, 743.

Embryos of Hemiptera, Glandular Struc-
ture on Abdomen of, 745.

Emerton, J. H., Changes of Internal Organs
in Pupa of Milkweed Butterfly, 379.

Emery, H., Bud of the Tulip-tree, 245.

Enchytroeides Marioni, Development of
Ccelom in, 387.

Endocarp in the Elder, Development of,
244,

Endoderm of the Stem of Selaginellacez,
785.

Endosperm, Doubling of, in Vascular
Cryptogams, 254.

— of Leguminose, 773.

Engelmann, T. W., Electric Illumination
with the Microscope, 450.

—., Electric Lighting applied to Micro-
graphy and Photomicrography, 696.

, Microspectrometer, 122.

——, Purple Bacteria and their relation
to Light, 105.

Enteric Canal of Ephemeride, 206.

Entocladia, 259.

Entocolax Ludwigii. Parasitic in a Holo-
thurian, 197.

Entomophthoree and their use in the
destruction of noxious Insects, 261.

——,, New, 9561.

Entophytes in Myriopods, 681.

Entozoa, Notes on, 757.

Entz, G., Nyctotherus in Blood of Apus
caneriformis, 75.

Eozoon Canadense, 401.

Ephedra, Stem of, 82.

Ephelis, New Development of, 562.

Ephemeridx, Enteric Canal of, 206.

Epiderm of the Seeds of Capsicum, 244.

— ., Starch in, 773.

Epidermis, Cellular, of Nematodes, 225.

of Serpulide, 515.

Epiphytic Vegetation of the Tropics, 414.

Epithelia, Investing, Indirect Nuclear
Fission in, 728.

Epithelial Glands in Batrachian Larva,
190.

Epps, H., Culpeper Microscope, 166.

Equisetum, Structure of the Commissure
of the Leaf-sheath of, 256.

Eranthis hyemalis, Formation of Subter-
ranean Swellings in, 247.

Eremothecium, a new genus of Ascomy-
cetes, 425.

Ergosterin, New Principle from Ergot of
Rye, 240.

Ergot of Rye, New Principle from, Ergo-
sterin, 240.

Eriksson, J., Haplobasidion, a new genus
of Dematiezx, 682.

INDEX.

Esmarch Plate, Counting the Colonies in,
471.

Roll Cultivation, Two Modifications
of, 458.

Esparto-grass, 784.

Eudrilide, New Genus of, 220.

Eudrilus, Reproductive Organs of, 58.

Euglena sanguinea, Pigment of, 768.

Euglypha alveolata, Karyokinesis in, 139.

Euphausiide, Metamorphosis of British,
752.

Eupbhrasia, Fertilization of, 89.

Euryale ferox, Flowering of, 250.

, Germination of Seeds, 250.

Eustrongylus gigas, Red Colouring Matter
of, 225.

Evans, W. H., Stem of Ephedra, 82.

Evolution, Divergent, through Cumulative
Segregation, 33.

Ewell, M. D., American Objectives and Dr.
Zeiss’s Apochromatie Objectives, 276.

, Glass versus Metal Micrometers, 445.

, Micrometer Measurements, 447.

Excretory Organs, 368.

Exostemma, Cystoliths in, 405.

Eye, Compound of Alpheus, Development
of, 382.

, Heteropod, 196.

of Decapod Crustaceans and Arach-

nids, 742.

of Limulus, Structure and Develop-

ment of, 747.

, Shellac Injection for the Vessels of,

50

Eye-pieces. See Contents, xxxilii.
Eyes of Acalephe, 532.

— of Gastropods and of Pecten, 38.
— of Mollusca, 626.

F.

F. C. 8., Beginner’s Guide to Photography,
283.

Fabre - Domergue, —.,
Protozoa, 832.

, First principles of the Micro-

scope, 136.

- ——, Functional Differentiations in

Unicellular Beings, 534.

, New Ciliate Infusoria from

Conearneau, 398.

, Reserve Substances in the

Protoplasm of Infusoria, 74.

, Two New Infusorians, 535.

Falter’s (G.) Rotating Ubject-holder, 276.

Falzacappa, E., Nerve-cells in Birds, 494.

Famintzin, A., Symbiosis of Algze and
Animals, 767.

Farlow, W. G., Apospory in Pteris aquilina,
256.

Farmer, J. B., Development of the Endo-
carp in the Elder, 244.

, Germination of the Megaspore of

Tsoetes, 551,

Examination of

865

Farnani, J., Genital Organs of Thely-
phonus, 750.

Farrant’s Medium, Hints on Mounting
Objects in, 714.

Fasoldt, C., Obituary Notices of, 702, 829.

, * Patent Microscope,” 109.

Favus (Achorion Schonleinii), Culture of
Fungus of, 296.

Fayod, V., Boletopsis, a new genus of
Hymenomycetes, 792.

—, Hymenoconidium, 427.

, New application of Photography to
Botany, 835.

Fecundation and Segmentation of Ova of
Rats, 490.

Felix, W., Growth of Transversely Striated
Muscle, 730.

Fell, G. E., Report of Committee on
Micrometry, 294.

Ferment from putrefactive Bacteria, 104.

— Organism, Protoplasm considered as
a, 107.

Fermentation, Sarcine of, 106.

Ferns, Antherozoids of, 552.

See Cryptogamia Vascularia, Con-
tents, xxvi.

Ferria, L., 308.

Fertilization and Maturation of Ova in
Ascaris marginata, 223.

of Ovum in the Lamprey, 189.

and Segmentation in Ascaris megalo-
cephala, 220.

——,, Cross, in Hydrangea, 250.

in Helix aspersa and Arion empiri-

corum, 372.

in the Nyctagineex, 249.

— of Amorphophallus Rivieri, 411.

— of Euphrasia, 89.

— of Lonicera japonica, 249.

Fewkes, J. W., Angelopsis, 648.

——,, Development of Calcareous Plates of
Asterias, 61.

——, New Athorybia, 532.

——, —— Marine Larva, 644.

—, Parasite of Amphiura, 54.

, Stalked Bryozoon, 201.

Fibres in Monstera, 661.

, Libriform, Formation and Develop-
ment of, 776.

Fibrovascular Bundles in the Petiole of
Nierenbergia rivularia, 242.

Fickert, C., The Markings of Lepidoptera
in the genus Ornithoptera, 743.

Ficus, Foliar Medullary Bundles, 777.

Fig, Respiration of, 550.

Filaria medinensis in Animals, 756.

Filicine, Root of, 785.

Finder, 121.

Finland, Calanida of, 215.

Firtsch, G., Variations of Vibrio proteus,
570.

Fischer, C., French Pennatulids, 393.

—, E., Cyttaria, 42+.

——., K., Distribution of Unio margaritifer,
376.

866

Fischer, P., Arrangement of Tentacles in
Cerianthus, 761.

Fish-scales, Mounting, 832.

Fishes, Bony, Development of, 3

, Injecting and Preparing fe Cireu-
latory System of, 307.

—-, Teleostean, Reproduction
Development of, 491.

FVissurella, Ventral Nervous Mass of, 496.

Flagella of Cholera Bacilli, 571.

of Spirilla and Bazilli, Staining,

and

837.

Flagellated Chambers in Sponges, 648.

Flal hault, C., Heterocystous Nostocacez,
103.

Flask Cultivations, 458.

Flemming, W., Solubility of Fat and
Myelin in Turpentine Oil after the
action of Osmic Acid, 714.

Fletcher, J. J., Australian Harthworms,
515.

Floating-leaves, Development of, 88.

-Organs, 779.

, Mechanical Structure of, 240.

Floral Axes, Anatomy of, 656.

Floridez, Antherids and Pollinoids of,
674.

, Development of Tissues in, 555.

Flot, L., Impregnation in Black of Tissues,
838.

, Tigellum of Trees, 546.

Flowers and Bees, 505.

, Cleistogamic, 412.

——,, Colouring-matter of, 80.

——, Constancy of Insects in visiting,
249,

——.,, Perforation of, by Insects, 667.

, scent of, 253.

, Spectrum analysis of colours of, 403.

Fluids, Conduction of, through the Albur-
pum, 90.

Flustrella hispida, Structure and Metamor-
phosis of Larva of, 501.

Fly-catching Habit of Wrightia coccinea:
412

Focusing up or down too much in the
Microscope, Optical Effect of, 134.

Fodder and Seeds, Bacteria of, 268.

Foerster, —., Proposals for the establish-
ment of a public telescopic, spectroscopic,
and microscopic observatory, 294.

Foetus, Human, Development of Nail in,
620.

Foex, G., Structure of White Rot, 100.

Fol, H., Microscopie Anatomy of Denta-
lium, 737.

Foliar Organs of a, new species of Utricu-
laria, 245.

Foodstuff, Ordinary, as Media for propo-
gating Pathogenic Micro-organisms,
296.

Foraminifera of the London Clay, 483.

, Reproduction of, 771.

Forces which determine the Movements in
the Lower Organisms, 90.

INDEX.

Formad, H. F., Liquids for Re-moistening
Blood, 159.

Forstetter, E., New methed for the Bac-
teriological Examination of Air, 843.

Fossil Marine Diatoms, 566.

Foster, R. A., Investigation of Bacteria by
means of Cultivation, 704.

Foureur, A., Culture of Anaerobic Micro-
organisms, 704.

Fowl-embryo, Tuberculous Infection of,
569.

Fowler, G. H., Pennatulida of Mergui
Archipelago, "529,

The Remarkable Crustacean Parasite,
641.

——, Two new Types of Actiniaria, 70.

Fraenkel, C., Photomicrographic Atlas of
Bacteriology, 107.

Fragaroides aurantiacum, Monograph, 40.

, Method of Examining, 138.

France, Marine Acarina of Coasts, 509.

Franchet, A., Primula with Anatropous
Seeds, 663.

Frank, B., Absorption of Nitrogen by
Plants, 412.

, Assimilatioa of Free Nitrogen by

the Lower Organisms, 550.

, Physiological Significance of My-

corhiza, 261.

, Power of Plants to absorb Nitrogen
from the air, 782.

Freeborn, G. C., Carminic Acid Stain,
305.

—, Histological Technique of the Blood,
844.

—, Macerating Fluid for Nerve-cells,
298.

——, Notes on Histological Technique,
159.

——, Notices of New Methods, 314, 471.

, Staining Connective Tissue with
Nigrosin (Indulin, Anilin Blue-black),
305.

——, Substitute for Corks in Imbedding,
305, 462.

Freese, W., Anatomy and Histology of
Membranipora pilosa, 4

French Malacology, 733.

Pennatulids, 393.

Fresh-water Bryozoa, Preparing, 138.

Freudenreich, H. de., Antagonism of the
Bacillus of Blue Pus and Anthrax, 798.

Friedlander, B., Central Nervous System
of Lumbricus, 56, 706.

Fries, T. M., Pilophorus, 680.

Fritze, A. , Enteric Canal of Ephemerida,
206.

Frog, Ova Penetration of Spermatozoa, 727.

, Simple Method of freeing, 599.

Frommann, C., Vital Processes in Living
Cells, 492,

Fruit of Grasses, 663.

Fruit-scales of Abietines, 407.

Fruits, Development of Berry-like and
Fleshy, 662.

INDEX.

Fucacez, Antherozoids of, 675.

Fulton, T. W., Dispersion of the Spores of
Fungi by Insects, 792.

Fungi, mounting, 461.

See Contents, xxviii.

Fungia, Natural History of, 231.

Fusari, R., Peripheral Nervous System of
Amphioxus, 625.

- G.

G. H. C., Glycerin Mounts, 309.

Gabbi, U., New and rapid. method of
staining the capsule of Bacillus pneu-
moni, 601.

Gage, S. H., Form and Size of Red Blood-
corpuscles of Adult and Larval Lam-
preys, 494.

, and §. P., Staining and Mounting
Elements which have been treated with
Caustic Potash or Nitrie Acid, 713.

Galeazzi, R., Nervous Elements of Adduc-
tor Muscles of Lamellibranchs, 201, 299.

Galega officinalis, Tubercles on the Roots
of, 546.

Galileo, Compound Microscope invented

Gall-producing Species of Chermes, Bio-
logy of, 506.

Gallemaerts, —., Method for fixing Serial
Sections to the Slide, 839.

Galls produced on Typhlocyba rose, 636.

Gamaleia, N., Natural mode of infection of
Vibrio Metschnikoyi, 430.

Garbini’s (A.) small Steam-generator for
Microscopical Technique, 155.

Garcin, A. G., Pigment of Euglena san-
guinea, 768.

, Structure of Apocynacez, 660.

Gariel, C. M., Studies in Geometrical
Optics, Dioptrics, Centered Systems,
Lenses, Optical Instruments, 294.

Garman, H., New Earthworm, 220.

Garnault, P., Fertilization in Helix
aspersa and Arion empiricorum, 372.

, Reproductive Organs of Valvata
piscinalis, 498.

Garstang, W., Nudibranchiate Mollusca of
Plymouth Sound, 737.

Gartner, A., Chemical and Bacteriological
Examination of Water, 605.

Gases in Plants, Penetration and Escape
of, 549.

ae Submerged Plants, Exchange of,
670.

, Movements of, in plants, 782.

Gaskell, W. H., Origin of Nervous System
of Vertebrates, 360.

a G., Fermentation of Palm-wine,

66.

Gastrodes and Cunoctantha, 232.

Gastropacha, Hermaphroditism in, 503.

Gastropoda. See Contents, xii.

‘ Gazelle’ Expedition, Algz of, 555.

867

Geheeb, A., Mosses from New Guinea,
999.

Gelatin, Kaiser’s, for arranging micro-
scopical preparations in series, 153.

, Method of Preparing Nutritive, 457.

, Nitric Acid in, 603.

——, Presence of Nitric Acid in Nutrient,
457.

Generative Apparatus of Lymnzus, 195.

Cells, Female, in Podocoryne, Origin

of, 231.

, Organs, Female, and Oogenesis in
Parasitic Copepoda, 753.

Geneva, Rotifera from, 59.

Genital and Segmental Organs of Earth-
worm, 57.

Ducts, Female, of Acanthocephala,
519.

-— Organs of Thelyphonus, 750.

Genoa, Rhizopods of Gulf of, 237.

Geotropism of the Rhizoids of Marchantia
and Lunularia, 554.

Geraniacez, Integument of the Seed of, 88.

Germinal Layers, &c., in Cyprinoids, 31.

in Rana fusca, 30,

Germination of Phanerogamia.
tents, XXiv.

Germs, Methods for ascertaining the
Number of Atmospheric, 158.

Giacomini, C., Neurenteric Canal in the
Rabbit, 29.

Giard, A., Galls produced on Typhlocyba
rose by a Hymenopterous Larva, 636.
—., Morphology and Systematic Position

of the Dajide, 513.

, New Entomophthoracez, 561.

——, New Infusorian, 235.

—, Parasitic Castration of
dioica, 412.

, Crustacea, 512.

, Phosphorescent Infection of Talitrus
and other Crustacea, 749.

Giaxa, —., de, Number of Bacteria in the
Contents of the Gastro-enteric Tube of
some Animals, 63.

Gibbes, H., Logwood Staining Solution,
462.

Gibier P., Vitality of Trichine, 757.

Giesbrecht, W., New Pelagic Copepods,
640.

Giles, G. M., Indian Amphipoda, 53.

Gill, C. H., Preparing Diatoms, 834.

Gills, Movements of Detached, 40.

Gilson, G., Odoriferous Glands of Blaps
mortisaga, 744.

Giltay, E., Adaptation of Anatomical
Structure to Climatal Condition, 89.

Girod, P., Anatomy of Atax ypsilophorus
and A. Bonzi, 746.

Gland, Pericardial, of Annelids, 215.

Glanders, Staining the Bacillus of, 468.

Glands, Coxal, of Arachnida, 210.

——, Epithelial, in Batrachian Larve, 190.

on the Rhizome of Lathrea, 89.

Glass, Action of Bleaching Agents on, 314,

See Con-

Lychnis

868

Glass versus Metal Micrometers, 445.

Glaucothrix gracillima and Bacillus mu-
ralis, Relationship of, 103.

Glischrobacterium, 571.

Gluten in the Grain of Corn, 773.

Glycerin Mounts, 309.

Soap, Imbedding in, 835.

Glyciphagus domesticus and G. spinipes,
Life-histories of, 508.

—— , Encystation of, 509.

Gnentsch, F., Radial Connection of the
Vessels and Wood-parenchyme, 83, 776.

Gobi, C., Peroniella, a New Genus of
Schizophycee, 565.

Goebel, K., Stem and Leaf of Utricularia
780.

, Young State of Plants, 550.

Goehlich, G., Genital and Segmental
Organs of Harthworm, 57.

Goldi, E. A., Coffee-Nematode of Brazil,
518.

Goltzsch’s (H.), Second Binocular Micro-
scope, 685.

Gonococci, Staining and Detection of, 712.

Cordii, Cireum-intestinal Cavity of, 308.

Gordiids, Hypodermis and Peripheral
Nervous System of, 388.

Gordius, New Species of, 225.

, Ovary and Oogenesis of, 755.

Gourret, P., Two Infusorians from the Port
of Bastia, 398.

Govi, G., The Compound Microscope
invented by Galileo, 574.

Graafian Follicle in Didelphys, Structure
of, 722.

Graber, V., Structure and Phylogenetic
Significance of Embryonic Abdominal
Appendages in Insects, 743. ;

Graminex, Obtaining of Nitrogen by, 781.

, Stomates of, 545.

Grandis, V., Spermatogenesis during Inani-
tion, 728.

Granel, —., Origin of the Haustoria in
Parasitic Phanerogams, 660.

Graphidew, 263.

Grasses, Fruit of, 663.

growing in Water, Modifications in
Roots of, 666.

Grassi, B., Ancestors of Myriopods and
Insects, 630.

——, Embryology of Cestodes, 389.

—,, Grassia ranarum, 771.

, Intermediate Host of Tzenia cucume-

rina, 226.

, New Acarid, 638.

——, Preparing Megastoma entericum, 301.

——., Replacement of King and Queen of
Termites, 50.

-——, Termites, 50, 635.

Grassia ranarum, 771.

Gravet, F., Colouring-matter of Sphagna-
cee, 674.

Gray, W. M., Photomicrography, 283.

Greenland, Fresh-water Fauna of, 367.

Greenwood, M., Digestion in Hydra, 395.

INDEX.

Gregarine of Earthworm, Formation of
Spores of, 536.

Gregarines, New, 400.

Gregory, E. L., Development of Cork-
wings, 84, 242, 405.

Grenacher, H., Heteropod Eye, 196.

Greppin, L., Notes on some of the recent
methods of investigating the central
nervous system, 303.

Greig, J. A., New Cornularie, 230.

Griesbach, H., Demonstration .of micro-
scopical stained preparations, 308.

—, Double, Triple, and Quadruple
Staining, 464.

Griffiths, A. B., Liver of Carcinus mznas,
750. ;

——, Malpighian Tubules of Libellula de-
pressa, 745.

——, Method of Demonstrating Presence
of Uric Acid in Contractile Vacuoles of
Lower Organisms, 767.

, Micro-organisms and their Destruc-

tion, 794.

, saccular Diverticula of Asteroidea,
761.

——, Tubes and “ Hepatic Cells” of Ara-
neina, 746.

Grobben, C., Morphology of Pteropods, 194.

, Pericardial Gland of Annelids, 215.

Gréuwall, A. L., Inflorescence of Ortho-
trichum, 673.

Groom, P., Laticiferous Tubes, 775.

Grotto-Schizophycez and Bacillus muralis,
428.

Growth of Phanerogamia.
KOK

Gruber, A., Maupas’ Researches on Ciliata,
534.

, Rhizopods of Gulf of Genoa, 237.

Guerne, J. de, Fresh-water Fauna of
Greenland, 367.

Guignard, L., Antherids and Pollinoids of
Floridez, 674.

See Contents,

——, —— of Characee, 417.
——— of Ferns, 552.
——, —— of Fucacex, 675.

——, of Hepatices and Mosses, 554.

——, Pollen of the Cycadez, 772.

——, —-~—, Reservoirs of Gum in Rham-
naceex, 241,

Guignet, C. E., Soluble Prussian Blue, 463.

Gulbe, L. A., Periodical Activity of the
Cambium in the Roots of Trees, 549.

Gulick, J. T., Divergent Evolution through
Cumulative Segregation, 33.

Gum, Reservoirs of, in Rhamnaceex, 241.

Gunda ulvee, 519.

Gunnera, Colleters and Glands of, 780.

Giinther, C., Bacteriological Technique,
708.

Gymnosporangium, Cultures of, 791.

——, Heterospory of, 563.

INDEX.

H.

Haberlandt, G., Chlorophyll-bodies of
Selaginella, 92.

—, Leaves of Begonia, 245.

—, H., Geotropism of the Rhizoids of
Marchantia and Lunularia, 654.

Haddon, A. C., Irish Marine Fauna, 194.

, Revision of British Actinize, 647.

Haeckel, E., ‘ Challenger’ Siphonophora,
394.

Hematoxylin, Iodized, 837.

Haenseh’s Apparatus for Photographing ~

the Tarnish Colours of Iron Surfaces,
453.

Hagen, H. A., Double Plexus of Nervures
in Insects’ Wings, 742.

Halacaridie, 747.

Halkyard, E., Collection and Preparation
of Foraminifera, 709.

Hall, H. A., Bacillus from Urine, 848.

Halsted, B. D., Demonstration of Pollen-
mother-cells and Pollen-tubes, 600.

» Pollen-grains, 661.

——., Sensitive Stamens in Compositze, 778. |

Hamann, O., Anatomy of Ophiurids and
Crinoids, 525.

, Morphology of Crinoids, 528.

Hanausek, T. F., Epiderm of the Seeds of
Capsicum, 244.

Hanitsch, R., New British Sponge, 649.

Hansen, A., Pure Chlorophyll, 653.

, H. C., Micro-organism found in the
mucous flux of Trees, 795.

Hansgirg, A., Bacillus muralis and Grotto-
Schizophycee, 428. |

, Classification of Confervoides, 419.

—, of Cyanophyceee, 102, 567.

—., Crenacantha, Periplegmatium, and
Hansgirgia, 420.

— , Entocladia, 259.

—, Morphology and Physiology of the
Sulphur Bacteria, 567.

——, Pheodermatium, 676.

——,, Phyllactidium, 419.

, Tetraedron, 566.

Hansgirgia, 419, 420, 786.

Haplobasidion, a new genus of Dematies,
682.

Huaplocrinus, Ventral Structure of, 228.

Hardening Method, Benda’s, 142.

Hardy, J. D., Photomicrographic Appa-
ratus, 850.

, Syrup for keeping Rotifera quict,
475.

= We By
Sponges, 456.

Hargitt, C. W., Mounting Infusoria, 834.

Hariot, P., Delamarea, a new genus of
Pheeosporeze, 676.

Harmer, 8S. F., Anatomy of Dinophilus,
7958.

Hartig, R., Accumulation of Reserve-
substances in Trees, 242.

1889.

Collecting Salt-water

869

Hartig, R., Conduction of Fluids through
the Alburnum, 90.

——,, Diseases of Trees, 551.

, Movement of Sap in the Wood, 670.

Hartog, M. M., Adelphotaxy, 192.

, Functions and Homologies of Con-
tractile Vacuole in Plants and Animals,
192:

—, Method of investigating Cyclops,
300

, Morphology of Cyclops, 215.

——,, Structure of Saprolegniaces, 678.

Harz, C. O., Fixing of the Spores of
Hymenomycetes, 461.

——,, Fungi of Mines, 266.

Hasse, E., Anatomy of Blattide, 506.

Haswell, W. A., Comparative Study of
Striated Muscle, 729.

, Psilotum and Tmesipteris, 672.

Hatch, F. H., Rosenbusch’s Petrographical
Tables, 603.

Haustoria of Rhinanthacee, 665.

, Origin of, in Parasitic Phanerogams,
665.

Hazel, Germination of, 251.

Heath, A., Modified Ectoderm in Crania
and Lingula, 48.

Heathcote, F. G., Anatomy of Polyxenus
lagurus, 637.

Heckel, E., Cystoliths in Exostemma, 405,

——,, Pitchers of Sarracenia, 408.

Hegler, L., Thallin, a new reagent for
Lignin, 606.

Heidenhain, R., Preparing small Intestine,
298.

Heilprin, A., Marine Invertebrates of
Bermuda Islands, 194.

Heimerl, A., Fertilization in the Nycta-
gines, 249.

, Fruit of Nyctaginex, 544.

Heinricher, E., Influence of Light on the
Origin of Organs in the Fern-embryo,
Ot.

Heinricius, G., Development of Placenta in
Dog, 726.

Heinz, A., Mucous Disease of Hyacinths,
572.

Heliotropism of Phycomyees, 681.

Helix aspersa, Fertilization in, 372.

, Descent of Ova in, 497.

Hellriegel, H., Obtaining of Nitrogen by
Graminez and Legumiuosex, 781.

Helminthological Notes, 520, 758.

Helotium parasitic on Sphagnum, 263.

Hemiptera, Embryos of Glandular Struc-
ture on Abdomen of, 745.

Henderson, J. R., Anomura of the ‘ Chal-
lenger,’ 382.

Henking, H., Formation and Fate of Polar
Globules in Eegs of Insects, 502.

Hennéguy, F., Development of Bony
Fishes, 363.

——, Formation of Spores of Gregarine of
Earthworm, 536.

— , Influence of Light on Noctiluca, 75,

«

ee

870

Hennéguy, F., Sareosporidia in Muscles
of Palemon, 76.

Henrici, J. F., An Old Microscope of the
Culpeper Type, 276.

Hepatic Cells and Malpighian Tubes of
Ayaneina, 746.

Hepatic, Antherozoids of, 554.

——,, New, 257.

Hepworth, T. C., Book of the Lantern, 294.

Herdman, W. A., Nudibranchiata of Liver-
pool District, 627.

—, Tunicata of the Voyage of the
‘Challenger,’ 376.

Heredity, 34, 619.

Hericourt, J., Staphylococcus pyosepticus,
269.

Hermaphroditism and Diclinism, 667.

in Gastropacha, 503.

— of Aplysiz, 373.

—— of Lychnis dioica when attacked by
Ustilago, 85.

——, Protandric, of Myxine, 188.

Herrick, F. H., Development of Compound
Eye of Alpheus, 382.

, Life-history of Stenopus, 752.

Hesse, R., Tuberacez and Elaphomycetes,
679.

Heterospory of Gymnosporangium, 563.

Heurck, H. van, Recent Improvements in
Electric Lighting applied to Micro-
graphy and Photomicrography, 696.

——., New Optical Combination of Zeiss,
and the Beads of Amphipleura, 806.

-——, The Apochromatics judged in
America, 276.

Hexactinian, Edwardsia-stage in free-
swimming Embryos of, 763.

Heydenreich, —., Structure of Staphylo-
coccus pyogenes aureus, 270.

Hibernation of Peronosporee, 261.

Hickory Bud, Examining a Shell-bark,
707.

Hieronymus, G., Cleistogamous Flowers of
Tephrosia heterantha, 85.

» Dicranochete, a new genus of Proto-
coccacee, 101.

Hildebrand, F., Properties of Hybrids, 781.

gone —., Bacteria of Fodder and Seeds,

Himalayan Uredinex, 790.

Hirudinea, Anatomy of, 516.

Hisinger, E., Tubercles of Ruppia and
Zannichellia, 547.

Histology. See Contents, x.

Hitcheock, R., The making of Apochro-
matics, 455.

Holmes’s (—.) Isophotal Binocular Micro-
scopes, 687.

Holotrichous Infusoria parasitic in White
Ants, 399.

Holothurian, Entocolax Ludwigii Para-
sitic in, 197.

Holothurians of Indian Archipelago, 67.

Holschewnikoff, —., Bacteria which pro-
duce Sulphuretted Hydrogen, 567.

INDEX.

Holway, E. W. D., Use for the Microscope
during the winter months, 314.

Honey, Production of, in Conyallaria, 655.

Hooker, H. E., Cuscuta Gronovii, 410.

Hooping Cough, Parasitic Protozoa in,
651

Hope, R., New British Species of Micro-
ciona, 396.

Horse-chestnut, Dimorphism of the Flowers
of, 85.

Hot Springs, Diatoms of, 102.

Hough, R. B., Thin Sections of Timber,
837.

Hovelacque, M., Vegetative Organs of
Bignoniaces, Rhinanthacee, Oro-
banchez, and Utriculariacez, 410.

Hovenden, F., Examining Thin Films of
Water, 843.

—, Theory of the Continuity of Life,
831.

Hoyle, W. H., Metamorphosis of British
Kuphausiide, 752.

Hubrecht, A. A. W., Demonstration of the
De Groot Microtome, 305.

Hudson, C. T., 598.

, Australian Rotifera, 322.

——, Models of Rotifera, 473.

——, President’s Address, 169.

——, Rotifera, 759. j

Hueppe’s (F.) Bacteriology, 569.

Hughes’s (W. C.) Improved Microscopic
Attachment—Cheap Form, 116.

——, Patent Oxyhydrogen Microscope,
115

——, Special Combination Scientist
Optical Lantern, 117.

Human Embryo, Study of a, 362.

— Spermatozoa, Observations on, 190.

Humulus Lupulus and H. japonicus,
Order of Appearance of the first vessels
in the Leaves of, 84. ;

Hungary, Cladocera of, 215.

Hyacinths, Mucous Disease of, 572.

Hyatt, J. D., Preparing Sections of Spines
of Hchinus, 707.

Hybrids, Properties of, 781.

Hydra, Digestion in, 395.

Hydrachnida, Marine, 509.

——, New Genus of, 509.

Hydrangea, Cross-fertilization in, 250.

Hydrodroma, Anatomy of, 51.

Hydroida, New or rare Australian, 71.

Hydroleucites and Grains of Aleurone,
239.

Hygroscopic Movements in the Cone-
scales of Abietines, 88.

Tensions, 403.

Hymenoconidium, 427.

Hymenomycetes, Boletopsis, a new genus
of, 792.

——, Fixing of Spores, 461.

——, New Type of, 99.

Hymenoptera, New Organ of, 205.

— , Stigmata of, 505.

Hyphomycetes, Prolification in, 789.

INDEX.

Hypodermis and Peripheral Nervous
System of Gordiida, 388.
in Periplaneta orientalis, New Organ

and Structure of, 204, 745.

1
Ianovsky, F. G., Bacteriology of Snow,
972.

Illuminating. See Contents, xxxiii.

Illumination by means of Wide-angled
Cones of Light, Effect of, 721.

Illuminator, Adjustable Hemispherical,
126.

Imbedding. See Contents, xxxvi.

Imhiuser, L., Prasiola, 793.

Immersion Medium, Monobromide of
Naphthaline as, 119.

Inanition, Spermatogenesis during, 727.

Indian Amphipoda, 53.

Archipelago, Holothurians of, 67.

, Ophiurid Fauna of, 66.

Perichetide, 220.

Inflorescence, Secund, 778.

Infusoria, Ciliated, Multiplication of 72.

, Culture of, 703.

—., Examining Ants
Parasitic, 461.

, Fauna of the Bay of Kiel, 234.

—., Fresh-water, 398.

— ., Holotrichous, 767.

; » parasitic in White Ants, 399.

——, Investigation of, 833.

— , Merotomy of Ciliated, 397.

—, Mounting, 834.

— , New Ciliate, from Concarneau, 398.

—. or Little-known, 235, 535.

, Peritrichous, from the Fresh
Waters of the United States, 447.

——, Reserve Substances in the Proto-
plasm of, 74.

—, Two, from the Port of Bastia, 398.

Injecting. See Contents, xxxvi.

Inoculations, Preventive, 797.

Insectivorous Plants, Pitchered, 779.

Insects and Flowers, 781.

—, Constancy of, in visiting Flowers,
249.

, Mounting entire, 705.

International Competition in Microscepy,
455.

Tntestine, Preparing small, 298.

Inuus nemestrinus, Placenta of, 726.

Tnvertin, New method of recognizing small
quantities of, 607.

Todine Reactions of Cellulose, 467.

Trish Marine Fauna, 194.

Tron Surfaces, Schmidt and Haensch’s
Apparatus for Photographing the
Tarnish Colours of, 453.

Trritation-curvatures, Physical Explana-
tion of, 413.

Ishikawa, C., Origin of Female Generative
Cells in Podocoryne, 251.

for Intestinal

871

Isoctes, Germination of the Megaspore
551.

Isolating Objects, Apparatus for, 842.

Isopoda, Early Development of Blasto-
dermic Layers in, 639.

Istvanffi, G., Preparation of Fungi, 141.

Ives, J. E., Variation in Ophiura pana-
mensis and O. teres, 529.

—, New Ophiurids, 761.

J.

Jackson, C. Q., Bacillus of Leprosy, 568.

» H., Monobromide of Naphthaline as

an Immersion Medium, 119.

, R. T., Development of Oyster and
Allied Genera, 375.

Jadin, F., Secretion-reservoirs, 241.

Jakimoyitch, J. Demonstrating Transverse
Striations iu Axis-cylinders aud Nerve-
cells, 297.

James, F. L., Biographical Sketch of W.
J. Lewis, M. D., 136.

——,, Limpid Copal Solution, 154.

ee Philosophy of Mounting Objects,

62.

——, Red Stain for Vegetable Sections,
307.

——.,, Sharpening the Section Knife, 462.

, Staining and Detection of Gonococci,

712.

» The Old Nonsense still on its

Rounds, 276.

, Walue of the Microscope to the

Physician, 294.

, J. F., Development of Corynites
Curtissii, 264.

Jefiries, J. A., A new Method of making
Anaerobie Cultures, 704.

Jentys, 8., Action of Oxygen under high
pressure on growth, 90.

Jickeli, C. F.,Nervous System of Ophiurids,
527.

Jodin, V., Culture of Unicellular Algae,
137.

Johannsen, W., Gluten in the Grain of
Corn, 773.

John, G., Boring Sea-Urchins, 760.

Johnson, T., Reproduction of Sphero-
coccus, 258.

, W., Sporids of Lichens, 97.

Johnstone, A., Malpighian Tubes and
* Hepatic Cells” of Araneina, 746.

—, Saccular Diverticula of Asteroidea,
761.

Joliet, L., Alternation of Generations in
Salpa and Pyrosoma, 47.

, Structure of Pyrosoma, 46.

Jonsson, B., Presence of a Sulphurous Oil
in Penicillium glaucum, 426.

Jordan, K., Anatomy and Biology of
Physapoda, 203.

Joseph, M., Vital Reaction of Methyl-
blue, 463.

3P 2

872

INDEX.

Journal, Changes in the Botanical Section | Klaatsch, H., Double staining of Ossifica-

of, 167.

Joyeux-Laffuie, J., Delagia Cheetopteri,
377.

Juel, H. O., Structure of Maregraviacez,
248.

Jumelle, H., Chlorophyllous Assimilation
and Transpiration, 669.

—, Development of Annual Plants, 668,
784.

— , Fruit of Grasses, 663.

——,, Influence of Mineral Substances on
the Growth of Plants, 669.

Jungersen, H. F. E., Structure and
Development of Colony of Pennatula
phosphorea, 229.

Jungner, J. K., Anatomy of Dioscoreacez,
660.

K.

Kain, C. H., Collecting Diatoms, 137.

, Fossil Marine Diatoms, 566.

Kaiser’s Gelatin for arranging micro-
scopical preparations in series, 153.

Kalide, G., Eyes of Gastropods
Pecten, 38.

Kara Sea, Comatulids of, 227.

Karlinski, J., Bacillus murisepticus pleo-
morphus, a new pathogenic Schizo-
mycete, 570.

Karlsson, G. A,
Coniferee, 656.

Karsten, G., Development of floating-
Leaves, 88.

Karyokinesis in Euglypha alveolata, 139.

Kastschenko, W., Cutting Microscopical
Objects for the purpose of Plastic Re-
coustruction, 146.

Kefir, 99.

Kellicott, D. S., American Rotifera, 523.

— , Annual Address of the President of
the American Society of Microscopists,
294,

, Fresh-water Infusoria, 398.

Kerner y, Marilaun, A., Scent of Flewers,
253.

Kibbler’s (A.) Photomicrographic Camera,
127.

Kiel Bay Infusorian Fauna, 234.

Rhizopod Fauna, 769.

King’s (J. D.) Microtome, 709.

Kingsley, C. 8., Classification of Myrio-
poda, 209.

— , Minot’s Automatic Microtome, 143.

T. W., Leech’s meron Lantern

~ Mier oscope, 805.

Kirchner, O., Eleeomyces, a new type of
Fungi, 561.

Kitasato, S., Musk-fungus, 560.

iesistance of the Cholera Bacteria to
Heat and Drying, 270.

Kitton, F., New Species of Navicula, 101.

Kjellman, F. R., Frond of Chordariacee,
676.

and

Transfusion-tissue of

‘Kolliker, A.,

tion Sections, 308.

, Radial Micrometer, 447.

Klebahn, H., Cause of violent Torsion,
253.

—, Dissemination of the Spores in
Rhytisma acerinum, 426.

, Uredinee of Pinus Strobus, 564.

Klein, L., Diagrams of Microscopical
Objects for Class Teaching, 605.

——, Mounting Fresh-water Alge, 140.

-——, Permanent Preparations of Fresh-
water Algze, 139.

, Volvox, 558.

Klercker, J. E. F. af, Tannin-vacuoles,
404.
Klotz, J., Generative Apparatus of

Lymneeus, 195.

Knoblauch, E., Anatomy of the Wood of
Laurineee. 83.

Knipffer, P., Female Genital Ducts of
Acanthocephala, 519.

Kny, L., Formation of healing Periderm,
776.

Koch, G. v., Caryophyllia rugosa, 530.

-——, L., Haustoria of Rhinanthacez, 665.

and Max Wolz’s Lamp, 126.

Koch’s Comma Bacillus, Varieties of, 269.

Koehler, R., Double Forms of Spermatozoa,
371.

, Tegumentary Coverings of Anatifer
and Pollicipes, 513.

Koenike, F., New Genus of Hydrachnids,
509.

Koeppen, O. W., Nucleus in Dormant
Seeds, 772.

Kohl, F. G., Formation of Calcium oxalate
in plants, 655, 774.

, Growth of Albuminous Composition

of Cell-walls, 402.

Transyersely Striated
Muscular Fibre, 193.

Konkoly’s (N. vy. ), Microscope for observing
the Lines in Photographed Spectra, 436.

; for Reading the Knorre-Fuess
Declinograph, 437.

Kononezuk, P., One-sided hardness of
of Wood, 669.

Korotneff, A., Cunoctantha and Gastrodes,
23

Korotnewia desiderata and the Phylogeny
of Horny Sponges, 649.

Korschelt, E., Formation of Mesoderm in
Echinoderms, 645.

Kossinski, A., Staining differences in
resting and active Nuclei in Carcinoma,
Adenoma, and Sarcoma, 712.

Kowalevsky, A., Excretory Organs, 368.

Krabbe, G., Fixed daylight position of
Leaves, 545.

Krasan, F., Parallel Forms, 415.

Kraus, G., Physiology of Tannin, 654.

Kronfeld, M., Bees and Flowers, 505.

, Constancy of Insects in visiting

Flowers, 249.

INDEX.

Kronfeld, M., Fertilization of Euphyrasia,
89

Kruticky, P., Diosmose through the
Cellulose-pellicle of Phragmites com-
munis, 539.

, Movements of Gases in Plants, 782.

Krysinski’s (8.), Eye-piece Micrometer
and its uses in Microscopical Crystal-
lography, 448.

Kuhne, H., Staining of Sections to show
Micro-organisms in situ, 601.

: , The Bacillus of Glanders, 468.

Kiikenthal’s, —., Process of Staining
Sections simplified by mixing the
Staining fluids with turpentine, 463.

Kultschitzky, N., Maturation and Ferti-
lization of Ova in Ascaris marginata,
223.

Kunstler, J.,
Infusoria, 235.

, New Proteromonas, 768.

Kurz’s, W., Transparent Microscopical
Plates, S44.

New or Little-known

Ibe

Labarie, —., Anatomy of Floral Axes, 656,

Laboulbeniacex, 789.

Lactarius piperatus, 682.

Lagerheim, G., New Urocystis, 266.

, Olpidiella, a new genus of Chytri-
diacez, 262.

——,, Rostrupia, a new genus of Uredinez,
790.

Lahille, F., Relation of Tunicata to Verte-
brata, 376.

Lambs, Micro-organisms of Pneumonia of,
270.

Lamellibranchiata. See Contents, xii.

Lamellicorns, Larval, Alimentary Canal
of, 504.

Laminaria bulbosa, Bulb of, 556.

Lamna cornubica, New Cestodes from,
390.

Lamounette, —. Fibrovascular Bundles in
the Petiole of Nierenbergia rivularia,
243.

Lamp, Koch and Max Wolz’s, 126, 160.

Lamprey, Form and Size of Red Blood-
corpuscles, 404.

, Maturation and Fertilization of,
Ovum in, 189.

Landerer, J. J., Disturbances of Vision
consequent on Microscupie Observation,
817.

Lanyibaudiére, Bialle de, Mountain Dia-
toms, 469.

Lankester, E. R., Structure of Amphioxus
lanceolatus, 363.

Lantern, Hughes’ Special Combination
Scientist Optical, 117.

Illustrations of Microscopical Sub-

jects, 136.

Micrescope, Leach’s Improved, 803.

Larvee, Lepidopterous, 206.

873

ef V. A., Histology of the Teeth,

709.

me Methods for examination of the Eye,

35.

—, Notes on Practical Examination of
Muscle-fibres, 159.

Lathrea, Glands on the Rhizome of, 89.

Laticiferous ‘Tubes, 775.

Lattermann, G., Apparatus for measuring
very minute Crystals, 277.

Laurent, E., Cladosporium herbarum, 563.

, Formation of Starch from Organic
Solutions, 414.

Laurinee, Anatomy of the Wood of, 83.

Lauterbach, C., Secretion-receptacles in
the Cactacex, 656.

Laux, W., Vascular Bundles in the
Rhizome of Monoeotyledons, 243.

Leach, W., A Substage Condenser for the
Microscope, 698.

, Improved J.antern-Microscope, 803.

Leaf and Stem of Utricularia, 780.

Leat-sheath of Equisetum, Structure of
Commissure of, 256.

Leaves, Absorption of Light in assimilat-
ing, 412.

i of Water by, 671.

——, Anatomy of, 544.

——,, Colouring-matter of, 80.

containing Anthocyan, Change in

Colour of, 40+4.

, Decurrent and Winged Stems, 244.

——.,, Fixed daylight position of, 545.

—., Floating, Development of, 88.

——, Mineral Substances in, 240.

—— of Abietinez, Polymorphism of, 245.

of Begonia, 245.

of Humulus Lupulus, and H. japo-
nicus, Order of Appearance of the first
Vessels in, 84.

— of Sedum spectabile, Formation of
Starch in, 541.

, Photo-position of, 91.

——,, Trophilegie Function of, 670.

Lebrunia neglecta, 529.

Leckenby, —., Preparing and Mounting
Insects in Balsam, 600.

Leclere du Sablon, —., Endoderm of the
Stem of Selaginellacese, 785.

——,, Origin of the Haustoria in Parasitic
Phanerogams, 665.

, Stem of Ferns, 552.

Lecomte, H., Development of Sieve-plates
in the Phloem of Angiosperms, 405.

Lecythidacex, Structure of, 542.

Lee, A. B., Preparing ‘Tetrastemma
melanocephala, 139.

Leguminose, Mucilage in the Endosperm
of; 773:

, Obtaining of Nitrogen by, 781.

——,, Root-tubercles of, 246.

——, Tubercles of, 247.

Lehmann, O., Molecular physics, with
special reference to microscopical in-
vestigations, 294.

874

Leidy, J., Cliona, 534.

, New Gregarines, 400.

Parasitic Copepod, 641.

Leitzeb, H., Asparagin and Tyrosin
in Tubers of the Dahlia, 81.

, Spheerites, 81.

Leitz’s large Dissecting Microscope, 275.

No. 1 Stand, 438.

—— “Support” Microtome, 304.

Lemna trisulea, Photolysis in, 79.

Lendenfeld, R. v., Coelenterata of the
Southern Seas, 67.

, Monograph of Horny Sponges, 765.

——,, Structure of Flagellated Chambers
in Sponges, 648.

Léon, N., Nucina as a Staining Agent,
149.

Lepidoptera, Markings of, in the genus
Ornithoptera, 743.

—, Pollination by, 667.

, Spermatogenesis in, 743.

Lepidopterous Larvee, 206.

Lepidosteus osseus, Early Development of,
622.

Lepismid, Abdominal Appendages of, 636.

Leprosy, Bacillus of, 568.

Leptostraca and Nebaliide, 213.

Leptotrichic Acid, 553.

Leroy, C. J. A., Disturbances of Vision
consequent on Microscopic Observation,
817.

Lesueria vitrea, 71.

Letellier, A., Black Injection-mass, 151.

, Purple of Purpura lapillus, 627.

Leven, —., Staining Muscle with Saffron,
467.

Lévy, A. M, The Minerals of Rogks, 294.

Lewin, A., Baumgarten’s Triple Staining
Method, 149.

, A. M., Spore-formation in Bacillus
anthracis, 429.

Lewis, G., Mouth-organs of two species of
Rhysodidee, 208.

, W. J., Forensic Microscopy, 831.

Leydig, F., Argulus foliaceus, 333.

, structure of Nervye-fibres, 624.

Libellula depressa, Malpighian Tubules of,
745.

Liber-fibres, Primary, in the Root of
Malvacez, 84.

Lichenoporee, Ovicells of, 377.

Light, Absorption, in assimilating leaves,

, Effect of Illumination by means of

Wide-angled Cones of, 721.

, Influence of, on Pholas dactylus,

39.

,»——, on the Development of Bark,

549.

i , on the formation of Calcium

oxalate, 655.

, , on the Origin of Organs in the
Fein-embryo, 94.

Bias Orientation of Animals towards,
732

INDEX.

Light, Purple Bacteria and their relation
to, 105

Light-filter, Chromo-copper, 133, 700.

Lighton, W., Instantaneous changes of
Field, 701.

Lignier, M. O., Structure of Lecythidacez,
942.

Lignin, Thallin, a new reagent for, 606.

Liliaceze, Arborescent, Increase in thick-
ness of, 657.

Lily Disease, 265.

Limulus, Eye Structure and Development
of, 747.

Lindau, G., Origin and Development of
the Apotheces of Lichens, 262.

Lindner, P., Sarcine of Fermentation,
106.

Lindt, —., Pathogenic Fungus from the
Human Ear, 787.

Line, J. E., Volvox globator, 677.

Lingula, Modified Ectoderm in, 48.

Linstow, O., v., Anatomy of Phylline
Hendorfii, 521.

—, Helminthological Notes, 520.

——, Pseudalius alatus, 756.
List, J. H., Female Generative Organs and
Oogenesis in Parasitic Copepoda, 753.
Lister, J. J., Natural History of Fungia,
231.

Litoral Plants, 82.

Liver of Carcinus meenas, 750.

Liverpool, Nudibranchiata of district, 627.

Locard, A., French Malacology, 733.

Locomotion, Organs of Aquatic, 35.

Loeb, J., Orientation of Animals towards
Gravity, 732.

Loebel, O. Anatomy of Leaves, 544.

, Light, 732.

Loeffler, F., New Method of Staining the
Flagella and Cilia, 711.

Legwood Staining Solution, 462.

Lohman, H., Halacaride, 747.

“ Loiterer,” Notes on the Substage Con-
denser, 450. 7

Loman, J. C. C., Coxal Glands of Arach-
nida, 210.

, Structure of Bipalium, 226.

Lombardy Poplar, Parasitic Fungus on,
681.

Lomentaria, Apical cell of, 556.

London Clay, Foraminifera of, 483.

Lonicera japonica, Fertilization of, 249.

Lott, F. E. and C. G. Matthews, The
Microscope in the Brewery and Malt-
house, 695.

Lovén, S., New Echinoconid, 67.

Low, F., Biology of Gall-producing
Species of Chermes, 506.

Loew, O., Reduction of Silver in the living-
cell, 539.

Lowe, E. J., Varieties in Ferns, 552.

Lowne, B. T., Anatomy of Insects, 831.

, Diffraction Theory, 806.

Lubbock, J., Observations on Ants, Bees,
and Wasps, 49.

INDEX.

Lucas, A. H. §., Colour of Birds’ Eggs,
30

Luciani, L., Respiration of the Ova of
Bombyx, 635.

Lucifer-like Decapod Larva, 751.

Ludwig, F., Fertilization by Snails, 548.

, Micro-organism found in the mucous

flux ot Trees, 795.

, H., Echinodermata, 227, 524, 644.

—, —, Holothurians of Indian Archi-
pelago, 67.

» —, Ophiopteron elegans, 66.

—, —, Rhopalodina lageniformis, 392.

——, R., Microscopic twining Fungus, 563.

Lukjanow, 8. M., Club-shaped Nucleoli,
36

Lumbricus, Central Nervous System of, 56.

, Preparing Central Nervous System
of, 706.

Lumia, C., Respiration of the Fig, 550.

Luminosity of Noctiluca miliaris, 236.

Luminous Phenomena in Pholas dactylus,
736.

Lunularia, Geotropism of the Rhizoids of,
554.

Lustig, A., Micro-organisms of Mytilus
edulis, 429.

Lutz A., Cystodiscus immersus—a Myxo-
sporidium found in the gall-bladder of
Brazilian Batrachia, 537.

Lychnis dioica, Parasitic Castration of,
412.

, when attacked by Ustilago,
Hermaphroditism of, 85.

Lycopodium lucidulum, “Bulblets” of,
255.

— , Prothallium of, 94.

Lymnezus, Generative Apparatus of, 195.

Lymphatic Glands of Cephalopods and
Decapodous Crustacea, 495.

Lyon, H. N., Cements, Varnishes and
Cells, 471.

——, Improved Form of the “ Wright ”
Collecting Bottle, 295.

M.

Maas, O., Metamorphosis of Larva of
Spongilla, 765.

Macalpine, D., Movements of Bivalve Mol-
lusea, 40, 739.

Maeartili, L., Foliar Medullary Bundles of
Ficus, 777.

Macchiati, L., Synedra pulchella, Ktz., var.
abnormis, 566.

, Xanthophyllidrine, 240.

Macfarlane, J. M., Pitchered Insectivorous
Plants, 779.

McClure, C. F. W., Primitive Segmenta-
tion of Vertebrate Brain, 725.

M‘Coy’s, F. M., Zoology of Victoria, 35,
194, 732.

Macerating Fluid for Nerve-cells, 298.

M‘Gillivray, P. H., Zoology of Victoria, 35.

875
M‘Intosh’s (.D.) Microscope Attachment,
692

—, W. C., Development of Mytilus
edulis, 40.

——,, Lesueria vitrea, 71.

, Phoronis Buskii, 376.

M‘Kendrick, J. G., The Modern Cell-
Theory, 193.

Macloskie, G., Poison-apparatus of Mos-
quito. 51.

McMahon, C. A., Mode of using the
Quartz Wedge for estimating the
Strength of the Double-Refraction of
Minerals in thin slices of Rock, 286.

MacMunn, C. A., Chromatology of British
Sponges, 396.

MecMurrich, J. P., Actinology of the
Bermudas, 648.

——, Edwardsia-stage in Free-swimming
Embryos of a Hexactinian, 763.

——, Lebrunia neglecta, 529.

Macrosporium parasiticum, Life-history of,
562, 791.

Maddox, R. L., On the application of some
photomicrographic methods, 454.

Matucci, A., Tuberculous Infection of the
Fowl-embryo, 569.

Magzi, L., Protozoa on Mosses of Plants,
72,

Magnesium Light, Photomicrography with,

Magnifying Power, The Determination of,
A prevalent Error, 294.

Magnin, A., Hermaphroditism cf Lychnis
dioica when attacked by Ustilago, 85.
Maguus, P., Hibernation of Peronosporex,

261.

, Urophlyctis Kriegeana, sp. n., 561.

Malassez, L., Rest for Slides and for Culti-
vation Plates, 602.

Malerba, P., Glischrobacterium, 571.

Mallory, M. L., Volvox globator, 677.

Malpighian Tubes and “ Hepatic Cells ” of
Araneina, 746.

— Tubules in Arthropoda, Origin of,
742.

— of Libeilula depressa, 745.

Malvacez, Primary Liber-fibres in the
Root of, 84.

Mammals, Markings of, 30.

, Spermatogenesis in, 623,

Man, Spermatogenesis in, 365.

Manaar Gulf, Sponges from, 396.

Mangin, L., Iodine Reactions of Cellulose,
467.

, Penetration and Escape of Gases in
Plants, 549.

-——, Structure of the Cell-wall, 538.

Manicina areolata, Development of, 231.

Mantle of Acephala, Edge of, 198.

Manton, W. P., and others — Lantern
Illustrations of Microscopical Subjects,
136.

——, Microscopical Outfit for Physicians’
use, 4909.

876

Manton, W. P., Reagents in Microscopy,
159.

— , Rudiments of Practical Embryology,
159. :
Manuscripts, Detecting Alterations in, 717.

Mareceraviacex, Structure of, 248.

Marchantia, Geotropism of Rhizoils, 554.

Marine Animals, Preserving, 8382.

Markings of Mammals, 30.

Marktanner’s (G.) Instantaneous Photo-
micrographie Apparatus, 129.

Marshall, A. M., Pennatulida of Mergui
Archipelago, 529.

Marsilia e¢yptiaca, Germination of, 254.

Martelli, U., Dimorphism of the Flowers
of the Horse-chestnut, 85.

, Phosphorescence of Agaricus olearius,
564.

Martin, H., Rapid Method of Staining the
Tubercle Bacillus in liquids and in
tissues, 712.

——, N. H., Plea for the Microscope, 703.

Martinaud, —., Alcoholic Fermentation of
Milk, 783.

Martinotti, C., Reaction of Elastic Fibres
with Silver Nitrate, 137.

, G., Xylol-dammar, 153.

Mascart, M. H., Treatise on Opties, 703.

Masius, J., Placenta of Rabbit, 28, 621.

Maskell, W. M., Optical Effect of Focusing
up or down too much in the Microscope,
134.

Massa, C., Parthenogenesis of Death’s-head
Moth, 208.

Massachusetts, Desmids from, 16.

Massalongo, C., Germination of the Spores
of Spheeropsideze, 263.

Massart, J., Heliotropism of Phycomyces,
681.

, Penetration of Spermatozoa into Ova
of Frog, 727.

Massee, G., New Development of Ephelis,
562.

—, Revision of the Trichiacez, 325,
472.

Mattei, G. H., Pollination by Lepidoptera,
667.

Matthews, C. G., and F. EH. Lott, The
Microscope in the Brewery and Malt-
house, 695.

Mattirolo, O., Intercellular Spaces in the
Teeument of the Seed of Papilionacez,
T70.

, Polymorphism of Pleospora herb-
arum, 42,5.

Maupas, E., Agamic Multiplication of
Lower Metazoa, 753.

, Culture of Infusoria, 703.

—, Multiplication of Ciliated Infusoria,
72.

Researches in Ciliata, 534.

Maurice, C., Method of Examining Fraga-
roids, 138.

, Monograph of Fragaroides aurantia-

cum, 40.

INDEX.

Maury, P., Comparative Anatomy of Desert
Plants, 82.

Mawson and Swan’s Photomicrographic
Apparatus, 128.

Mayall, J., jun., Microscopes at the Paris
Kxhibition, 851.

Mayer, P., Injecting and Preparing the
Circulatory System of Fishes, 307.

Mazzarelli, G. ., Reproductive Organs of
Aplysiz, 628.

Meade, J., Stereoscopic Photomicrography,
846.

Measurements in microscopical work, The
need of making, 454.

Media for propagating Pathogenic Micro-
organisms, Ordinary Foodstuif as, 296.

, Solid, prepared from milk, 297.

Mediterranean Diatoms, 427.

Medullary Bundles, Foliar, of Ficus, 777.

Rays, Secondary, 777.

Medusze, Semzostomatous and Rhizosto-
matous, 530.

Meehan, F., Bract in Tilia, 407.

——, Cruoss-fertilization in Hydrangea,
250.

——,, Dichogamy, 548.

——, Dimorphism of Polygonum, 781.

——, Elastic Stamems of Composite, 544.,

——., Fertilization of Lonicera japonica,
249.

—, Glands on the Stamens of Caryo-
phyllaceze, 544.

——, Homology of Stipules, 779.

— ., Life-history of Yucca, 250.

, Secund Inflorescence, 778.

Megalotrocha, new species of, from Bris-
bane, 610, 613.

Megascolides australis, Anatomy of, 216.

Megaspore of Isoetes, Germination of, 551.

Megastoma entericum, Preparing, 301.

Méenin, P., Encystation of Glyciphagus,
509.

Melampsora, New, 266.

Melle, G., Staining Bacilli of Rhinoscle-
roma, 307.

Mellor, C. C., An Old Microscope of the
Culpeper Type, 276.

Melolontha vulgaris, Hge of, 506.

Membranipora pilosa, Anatomy and His-
tology ol, 47.

Menégaux, A., Morphology of Teredo, 498.

, Furgescenuce in Lamellibranchs, 375

Mer, E., Influence of Exposure on the
Growth of the Bark of Conifers, 669.

Mercer, A. C., “Method of using with
ease Objectives of shortest working dis-
tance in the clinical study of Bacteria,”
287.

Mergui Archipelago, Myriopoda of, 507.

, Pennatulida of, 529.

Merker, P., Colleters and Glands of
Gunuera, 780. ,

Merotomy of Ciliated Infusoria, 397.

Merrifield, F., Incidental Observations in
Pedigree Moth-breeding, 379.

INDEX.

Merrill, G. P., Eozoon Canadense, 401.

Meslin, G., 294.

Mesoderm, Formation of, in Echinoderms,
645.

Metaurus, Composition of the Marine Tri-
polis of the Valley of, 102.

Methyl-blue, Vital Reaction of, 463.

Methylen-blue, Impregnating Tissues by
means of, 838.

Metschnikoff, —., Pleomorphism of Bac-
teria, 795.

Meunier, —., Sporocarp of Pilularia, 785.

Meyer, A., Septated Vittze of Umbelliferz, |

662.

——., Structure of Chlorophyll-grains, 78. |

—, B., Saprophytic Development of
Parasitic Fungi, 682.

, E., Morphology of Annelids, 385.

Mez, C., Embryo of Umbellifere, 244.

s New Myrmecophilous Plant, 253.

Michael, A. D., Life-histories of Glyci-
phagus domesticus and G. spinipes,
508.

, Observations on the Special Internal
Anatomy of Uropoda Krameri, 1.

Michel, A., Cellular Epidermis of Ne-
matodes, 225.

Microbes, Development of Pathogenic, on
Media previously exhausted by other
micro-organisms, 458.

, Staining, black for Photomicro-
grapliy, 148.

Microciona, New British Species of, 396.

Micrococci, Movements of, 795.

Micrometer, The Anti-diffraction, 277.

, Glass versus Metal, 445.

— , Klaatschb’s Radial, 447.

, Krysinski’s Eye-piece, and its uses
in Microscopical Crystallography, 448.

—., Measurements, 447.

, Rogers’ Eye-piece, 443.

Micro-organisms and their Destruction,
794.

Microscope, Adams’s Large Projection
and Compound, 438.

, Akrens’ Giant, 273.

—. Polarizing Binocular, 685.

— and Adulteration, 136.

, Anderson’s Panoramic Arrangement

for, 799.

, Apparatus. See Contents, xxxiii.

—— Attachment, McIntosh’s, 692.

——, Binocular Dissecting, 275.

, Celebration of the ‘Third Centenary
of the Invention of, 702.

— , Charles L, 440.

, Compound, Invented by
574.

— , Crouch’s Petrological, 113.

——, Culpeper, 166.

—., Czapski’s Ear-(Tympanum), 112.

—, Duc de Chaulnes’, 118, 442.

during the winter months, 314.

—, Edinburgh Student’s, 802.

——.,” “ Fasoldt’s “ Patent, 109.

Galileo,

877

Microscope for Observing the Lines in
Photographed Spectra, Konkoly’s, 436.

— for Reading the Knorre-Fuess De-
clinograph, Konkoly’s, 427.

——,, Goltzsch’s Second Binocular, 685.

——, Hughes’ Patent Oxyhydrogen, 115,

— , Isophotal Binocular, 687.

——,, Lantern, Leach’s Improved, 802.

——,, Leitz’s large Dissecting, 275.

SS No. 1 Stand, 438.

—— Makers, A Good Hint to, 294.

——, Moreau's Monkey, 113.

——,, Nelson-Curties, 805.

| ——, Old Italian, 695.

, Petrological, Dick and Swift's
Patent, 432.
—., Pfeffer’s Botanical, 272.
——, Practical Utility of, to Textile

Workers, 309.
—, Queen’s Acme, No. 5, 695.
——,, Reichert’s Petrological, 113.
, Seibert’s 805.
——, Selecting, 695.
—, Stands. See Contents, xxxii.
> Stuart, 321.
——,, Substage Condenser for, 696.
——,, Swift’s Mineral, 274.
, Watson’s Edinburgh Student’s, 695.
reais American and European,
455.
at the Paris Exhibition, 851.
—— for Measuring the Radii of the
Curved Surfaces of the Eye, 688.
Microscopic Attachment, Cheap Form,
Hughes’ Improved, 116.
Microscopical Society, Scottish, 830.
Microspectrometer, Engelmann’s, 122.
Poe Asexual Reproduction of,
88.
papillosum, 757.
Microtome, King’s, 709.
—-—, Leitz’s “ Support,’ 304.
——, Minot’s Automatic, 143.
——,, Paoletti’s, Improved, 710.
—, Taylor’s Combination, 304.
, Wilks’ Improved, 836.
Microtomes, 305.
Mid-gut, &e., in Cyprinoids, 31.
Migula, W., Effect of Dilute Acids on
Algz, 418.
, Mode of Distribution of Alge, 95.
Mik, J., A Spinning Dipteron, 5v6.
Mildew of the Apple, 563.
Miles, J. L. W., Substage Ilumination by
simple devices, 698.
Miliakaris, 8., Tylogonus Agave, 427.
Milk, Alcoholic Fermentation of, 783.
, Solid Media prepared from, 297.
Milne, W., Rotifers Parasitic in Sphag-
num, 923.
Mimosa, Irritability of, 252.
Minchin, E. A., New Organ and Structure
- Bypedeess in Periplaneta orientalis,
| Mineral Microscope, Swift's, 274.

878

Mineral Substances in Leaves, 240.

, Influence of, on the Growth of
Plants, 669.

Mines, Fungi of, 266.

Mingazzini, P., Alimentary Canal of Larval
Lamellicorns, 504.

, Hypodermis of Periplaneta, 7495,

Minot’s, C. 8., Automatic Microtome, 143.

, Uterus aud Embryo, 489.

Miguel, P., Methods for Ascertaining the
Number of Atmospheric Germs, 158.

Mistletoe, Morphology of, 248.

Mitosis in Mammalia, Demonstrating, 831.

Miyabe, K., Life-history of Macrosporium
parasiticum, 562.

Mobius, K., Infusorian Fauna of the Bay
of Kiel, 234.

——, Red Organisms of the Red Sea, 236.

——, Rhizopod Fauna of Bay of Kiel,
769.

——, Swelling of Foot of Solen pellucidus,
201.

——, M., Askenasya polymorpha, 418.

——, —, Chetopeltis, 259.

, —, New Alge from Porto Rico, 97.

Moeller, H., Mode of occurrence of Tannin
in Plants, 541.

——, Photomicrographic Apparatus, 450.

—. Tests for Tannin, 606.

Molisch, H., Change in Colour of Leaves
containing Anthocyan, 404.

——,, Formation of Chlorophyll by Coni-
ferze in the dark, 541.

Mollusca, See Contents, xi.

Molluscoida, See Contents, xiii.

Monad, Parasitic, 399.

Moniez, R., Accidental Parasitism on Man
of Tyroglyphus farine, 509.

——,, Life history of a Free Nematode,
756.

Monkey Microscope, Moreau’s, 113.

Monobrachium parasiticum, 394.

Monobromide of Naphthaline as an Immer-
sion Medium, 119.

Monocotyledons, Lateral Roots of, 547.

——, Vascular bundles of, 243, 656.

Monstera, Fibres and Raphides in, 661.

Monteverde, N. A., Influence of Light on
the formation of Calcium oxalate, 655.

Monticelli, F. S., Cerearia setifera, 522.

—, Nervous System of Amphiptyches,
522.

——, Notes on Entozoa, 757.

Moore, N. A., Method of Preparing Nutri-
tive Gelatin, 457.

, 8. Le M., Photolysis in Lemra tri-
sulea, 79.

Moreau’s Monkey Microscope, 113.

Morgan, 'T. H., Chitin Solvents, 141, 303.

, Fate of Amphibian Blastopore, 727.

ep Origin of Test-cells of Ascidians,
740.

Morland, H., Mounting “selected” Dia-
toms, 840.

Morpurgo, B., New Formation of Cells, 493.

INDEX.

Mosquito, Poison-apparatus of, 51.

Mosso, A., Critival investigation of the
methods used in the study of blood-
corpuscles, 303.

Moth-breeding, Incidental Observations in
Pedigree, 379.

Mounting. See Contents, xxxvii.

Mouth-organs of two species of Rhysodide,
208.

-parts of Ancylus fluviatilis and
Velletia lacustris, 197.

Mucedinex, Simple, 422.

Mucilage in the Endosperm of Legu-
minose, 773.

Miiller, C., Structure of the Commissure of
the Leaf-sheath of Equisetum, 256.

——, G. W., Spermatogenesis in Ostracoda,
640.

——., J., Graphidee, 263.

—,, K., The utility of the His Embryo-
graph, 443.

—, N. J. C., Spectrum-analysis of the
Colours of Flowers, 413.

Miller, O., Auxospore of Terpsinoé, 794.

Influence of “Ringing” upon

Growth, 781.

, Movements of Diatoms, 793.

Muelleria Agassizii, Embryology of, 760.

Munnich, A. J., Culture of Fungus of
Fayus (Achorion Schonleinii), 296.

Murray, G., Avrainvillea, 558.

, Spongocladia, 557.

——,, Struvea, 260.

Musca vomitoria, Development in Egg of,
505.

——.,, Preparing, 299.

Muscinex, Preparation of, 304.

See Contents, xxvii.

ee Growth of Transversely Striated,
730.

——,, Staining, with Saffron, 467.

——,, Striated, Comparative Study of, 729.

, Structure of, 35.

Muscles, adductor, of Lamellibranchs,
nervous elements of, 201, 299.

Muscular Fibre, Transyersely Striated, 193.

Mushroom, Phosphorescent, 565.

Musk-fungus, 560.

Mycoidea, 419.

Mycorhiza, New Cases of, 422.

——,, Physiological Significance of, 261.

Mycorhiza-forming Fungi, 678.

Mycose on the Sporange of Mosses, 505.

Myriopoda. See Contents, xiv.

Myrmecophilous Insects, 503.

Plant, New, 253.

Mytilus edulis, Development of, 40.

, Micro-organisms of, 429,

ee, Protandric Hermaphroditism of,
188.

Myxomycetes, New, 683.
— of Denmark, 682.

INDEX.

iN.

Nadelmann, H., Mucilage in the Endo-
sperm of Leguminose, 773.

Nail, Development of, in Human Foetus,
620.

Nansen, F., Protandric Hermaphroditism
of Myxine, 188.

Nautilus Pompilius, Structure of Siphon
and Funnel of, 495.

Navyicula, New Species of, 101.

Nawaschin, §., Helotium parasitic on
Sphagnum, 263.

Nebaliide and Leptostraca, 213.

Nectarial Scales of Ranunculus, 662.

Nectaries, Extrafloral, 543.

,» ——, in Composite, 87.

» ——,, of Dioscorea, 543.

Nelson, E. M., A means for the detection
of Spurious Diffraction Images, 612.

, Amphipleura pellucida, 321.

—., An Instrument for exhibiting the
1/2500 in. without a lens, 702.

—, “Back of the Objective and the
Condenser,” 288.

——,, Diatom Structure, 701.

—,, Diffraction Theory, 807.

——,, Elementary Centering Substage, 846.

— , Formation of Diatom Structure, 702.

, Nelson-Curties Microscope (Large
Model), 8v0.

—,, Observations on Human Spermatozoa,
190.

——,, Popular Explanation of Interference
Phenomena, 294.

—, The Action of the Wide-angled
Illuminating Axial Cone, and its rela-
tion to the Diffraction Theory, 472.

Nematiielminthes. See Contents, xvii.

Nematode, Free, Life-history of, 756.

in Blood of Dog, 58.

Nematodes, Anatomy and Ontogeny of,
224.

—., Cellular Epidermis of, 225.

, Examination of, 300.

Nematophyton, 560.

Nemertines, Nervous System of, 519.

Nepenthes, Pitcher of, 779.

Nephridia and Ccelom of Palzmon serratus,
749.

of Earthworms, 218.

Nerve-cells and Axis-cylinders, De-
monstrating Transverse Striations in,
297.

in Birds, 494.

—— -— ,, Macerating Fluid for, 298.

—— -—,, New Methods for Preparing,
598.

- fibres, Structure of, 624.

Nervous Elements of Adductor Muscles
of Lamellibranchs, 201, 299.

Mass, Ventral, of Fissurella, 496.

— System, Central, of Amphibians,
Development of, 188.

879

Nervous Mass, Ventral, of Lumbricus, 56,
706.

——, — _, of Vertebrata, Evolution

of, 187.

of Amphioxus, 36.

—— — of Amphiptyches, 522.

of Annelids, Influence on

Symmetry of Body, 514.

of Nemertines, 519.

—— —— of Ophiurids, 527.

—— —— of Vertebrates, Origin of, 360.

, Peripheral, and Hypodermis of

Gordiide, 388.

» ——, of Amphioxus, 625.

—— ——,, Vertebrate, Annelidan Affinities
in Ontogeny of, 192.

— Systems, Preserving, 460.

Tissue, Carmine Staining of, 148.

Nervures, Double Plexus of, in Insects’
Wings, 742.

Neudorf, F., Jr., Charles Fasoldt, Sr.’s
Rulings, 702.

Neuhauss, R., Flagella of the Cholera
Bacilli, 571.

—, Guide to preparing Photomicro-
graphs, 283.

——,, Staining Microbes black for Photo-
micrography, 148.

Neumayr, M., Origin of Unionide, 498.

Neurenteric Canal in the Rabbit, 29.

Neurology of Prosobranchiata, 372.

New Guinea, Mosses from, 553.

South Wales, Bryozoa of, 629.

— Zealand and Australia, Algee of, 97.

—— and Cape Species of Peripatus,

Maturation of Ovum in, 507.

, Oligochetous Fauna of 754.

a

3
Nickel, E., Staining reagents for Wood,
“7. 60L:
Nierenbergia rivularia, Fibrovascular

Bundles in the Petiole of, 242.

Niessing, G., Spermatogenesis in Mam-
mals, 623.

Nigrosin, Staining
with, 305.

Nitric Acid, Presence of, in Nutrient
Gelatin, 457.

Nitrogen, Absorption of, by Plants, 412.

, Free Assimilation of, by the Lower
Organisms, 550.

— in Putrefaction,
414.

— in the soil, Relation between the for-
mation of Tubercles and the presence
of, 251.

, Obtaining of, by Graminez and Legu-

minose, 781.

Power of Plants to absorb, from the
Air, 782.

Noack, F., Mycorhiza-forming Fungi, 678.

Noctiluca, Influence of Light on, 75.

— miliaris, Luminosity of, 236.

Noll, F., Cellulose-fibres of Caulerpa,
508.

—,, Colouring-matter of Bangia, 418.

Connective Tissue

Development of,

880

Noll, F., Influence of Position on the
Morphological Development of some
Siphonocladacee, 421.

——, Physical Explanation of Irritation-
curvatures, 413.

, Shining of Schistostega osmundacea,

257.

Structure of the Cell, 772.

Norderling, K. A., New Method for
staining the Tubercle Bacillus, 713.

Nordquist, O., Calanida of Finland, 215.

Nordstedt, O., Algzee of New Zealand and
Australia, 97.

Norman, A. M., British Amphipoda, 511,
639.

—, Ostracoda of North Atlantic and
North-western Europe, 512.

Nostoc, Parasitism of, 567.

Nostocaceze, Heterocystous, 103, 793.

Notochord, &c., in Cyprinoids, 31.

in Rana fusea, 30.

Nucina as a Staining-Agent, 149.

Nuclear Fission, Indirect, in Investing Epi-
thelia, 728.

Origin of Protoplasm, 239.

Nuclearia delicatula, 770.

Nucleoli, Club-shaped, 36.

Nucleus and Cell-body, Relation between,
493.

—— in Dormant Seeds, 772.

or nucleoid bodies of Schizomycetes,
429.

Nudibranchiata of Liverpool District, 627.

Nussbaum, M., Formation and Number of
Polar Globules in Cirripedes, 385.

, Heredity, 34.

Nutrition of Phanerogamia.
tents, XXv.

Nutritive Gelatin, Method of Preparing,
457.

— Media for the Cultivation of Bacteria,
456

See Con-

Nyctaginee, Fertilization in, 249.

, Fruit of, 544.

Nyctotherus in Blood of Apus cancri-
formis, 75.

Nympheacez, Seed of, 407.

O.

Obdiplostemonous Flowers, 661.

Oberbeck, A., Simple Apparatus for
Measuring the Magnification of Optical
Instruments, 700.

Object-holder, Falter’s Rotating, 276.

Objective “ Back of, and the Condenser,”
288.

Objectives. See Contents, xxxiii.

Odoriferous Glands of Blaps mortisaga,
7A.

Oil, Presence of a Sulphurous, in Peni-
cillium Glaucum, 426.

Oleomargariscope, Taylor’s, 696.

Oligochzta, Notes on, 754.

INDEX.

Oligochata of Plymouth, Marine, 515.

Oligochetous Fauna of New Zealand, 754.

Olive, Bacillar Tumours of, 546.

Olpidiella, a new genus of Chytridiacez,
262. ;

Onion, Vesicular Vessels of, 775.

Ontogeny and Anatomy of Nematodes,
224.

Oogenesis in Parasitic Copepoda, 753.

of Gordius, 755.

Ophiopteron elegans, 66.

Ophiura panamensis and OQ. teres, Varia-
tion in, 529.

Ophiurid Fauna of Indian Archipelago,
66.

Ophiurids, Anatomy of, 525.

, Nervous System of, 527.

, New, 761.

Optic Nerve in Vertebrata, Examining the
Central Termination of, 460.

Optical Properties of the Cuticle and
Suberized Membranes, 78.

Ordmann, —., Value of Bacteriological
Examination for Estimating the Purity
of Drinking Water, 604.

Orientation of Animals towards Gravity,
and Light, 732.

Origin of Species, 31.

Ornithoptera, Markings of, 743.

Orobanchee, Vegetative Organs of, 410.

Orr, H., Development of Central Nervous
System of Amphibians, 188.

Orthotrichum, Inflorescence of, 673.

Ortmann, A., Madrepore Corals from Cey-
lon, 762.

Oscillaria and Diatoms, Movements of,
566.

Osphradium of Mollusca, Innervation of
133.

Osseous Tissue, Fundamental Structure of,
731.

Ossification, Process of, 367.

Ostracoda, Marine, 214.

— of North Atlantic and North-western
Europe, 512.

, Spermatogenesis in, 640.

Otoplana intermedia, 643.

Oudemans, J. T., Abdominal Appendages
of a Lepismid, 636.

, Thysanura and Collembola, 208, 299.

Ores Eee Simple Method of freeing,
099.

— in Ascaris marginata, Maturation and
Fertilization of, 223.

— in Helix, Descent of, 497.

— of Bombyx, Respiration of, 635.

eae Caprella ferox, Investigation of,
599.

—— of Rats, Fecundation and Segmenta-
tion of, 490.

of Sepia, Investigation of, 460.

Ovaries of the Rose, 778.

Ovary and Oogenesis of Gordius, 755.

Ovicells of Cyclostomatous Bryozoa, 377.

of Lichenopore, 377.

INDEX.

Ovuliferous Seales of Coniferze, 777.

Ovum in Lamprey, Maturation and Fer-
tilization of, 189.

of Cephalopods, New Phenomenon of
cleavage in, 734.

Owen, Letter of Darwin to, 454.

Oxalie Fermentation, 550.

Oxalis, Trimorphism of, 667.

Oxidation, Process of, in Living Cells,
550.

Oxygen, Action of, under High-pressure
on Growth, 90.

, Free, Decomposition of Albumen in
the absence of, 92.

——, ——, Products of the Decomposition
of Albuminoids in the absence of, 253.
——,, Influence of, in the Decomposition

of Albuminoids, 783.
—— Pressure, Protoplasmic Movements
and their Relation to, 732.
Oxyhydrogen Microscope, Hughes’ Patent,
115

Oyster and allied Genera, Development of,
375.

P

Paoleiti’s (V.) Improved Microtome, 710.

Pachysterigma, 564.

Packard, A.S., Factors in the Evolution
of Cave Animals, 191.

Palemon, Sarcosporidia in Muscles of,
76,

— serratus, Coelom and Nephridia of,
749.

Palisade-parenchyme, 82, 241.

Palladin, W., Decomposition of Albumen
in the absence of free oxygen, 92, 253.

, Influence of Oxygen in the Decom-
position of Albuminoids, 783.

Palm-wine, Fermentation of, 266.

Palmella uveformis and Draparnaldia
glomerata, Genetic Connection of, 95.

Palps in Insects, Function of, 742.

Pammel, L. H., Perforation of Flowers by
Insects, 667.

Pangenesis, Intracellular, 547.

Panic Fermentation, 253.

Pantocsek, J., Finder, 121.

Pantopoda, Morphology and Larve of, 509.

Papilionaceze, Bacteria of the Tubercles of,
430.

—-, Intercellular Spaces in the Tegument
of the Seed of, 775.

Pappenheim, K., Closing of the Bordered
Pits in Conifere, 542.

Paraffin, Imbedding in, 462.

Oven with Simple Arrangement for
Maintaining a constant Temperature,
156.

Parallel Forms, 415.

Parasite, New, of Amphiura, 54.

Parasites on Trees, 93.

Parasitic Fungi, new, 264.

on lower animals and plants,

423.

881

Parasitic Mollusca, New Genus of, 374.

Monad, 399.

Paris Exhibition of 1889, Microscopical
Laboratories at, 703.

Parthenogenesis of Death’s-head Moth,
208.

Pathogenic Fungus from the Human Ear,
787.

Pathology, Vegetable, 105.

Patouillard, N., Coleopuccinia, 564.

Patten, W., Segmental Sense-Organs of
Arthropods, 504.

Peach-yellow, 792.

Pear, Sclerenchymatous Cells in the Flesh
of, 242,

Peck, J. I., Anatomy and Histology of
Cymbuliopsis calceola, 734.

Pecten, Hyes of, 38.

Pelletan, J., Distinction between “ micro-
graphes ” and “ microscopistes,” 703.

, Microscopy at the Universal Ex-
hibition of 1889, 703, 831.

Pelseneer, P., Abranchiate Lamellibran-
chiata, 740.

— Anatomy of Deep-sea Mollusca, 369.

Innervation of Osphradium of Mol-

lusea, 733.

, Morphology of Spinous Sacs of Gym-

nosomatous Pteropoda, 496.

Systematic Position of Desmopterus
papilio, 734.

Penard, E., Dino-Flagellata, 399.

Penhallow, D. P., Nematophyton, 560.

Penicilliopsis, a new genus of Ascomy-
cetes, 424.

Penicillium glaucum, Presence of a Sul-
phurous Oil in, 426.

Pennatula phosphorea, Structure and De-
velopment of Colony of, 229.

Pennatulida of Mergui Archipelago, 529.

Pennatulids, French, 393.

Penny, R. G., Microscope Objectives—
Angular Aperture, 135.
Pentastomum denticulatum

Migrations of, 212.
Peragallo, —., Mediterranean Diatoms, 427.
, Preparing and Mounting Diatoms,

169.
Pereyaslawzewa, 8., Development of Am-

phipoda, 511.

, Investigation of Ova of Caprella

ferox, 599.

Perez, J., Descent of Ova in Helix, 497.
Pericardial Gland of Annelids, 215.
Pericheta, Coccidium infesting, 76.
Perichetidz, Indian, 220.

Pericycle, 659.

Periderm and Assimilating Tissue in

leafless plants, 541.

, Formation of healing, 776.

——,, Researches on, 406.

Peripatus, Brain of, 745.

Maturation of Ovum in, 507.

— Nove-Zealandiz, Development of,

210.

in Cattle,

882
Periplaneta orientalis, Hypodermis of, 204,

Periplegmatium, 420.
Peristome of Mosses, 257, 673.

Perken, Son, and Rayment’s Photomicro- |
| Photomicrography. See Contents, xxxiii.

graphic Apparatus, 283.
Peroniella, a New Genus of Schizophycez,
565.
Peronosporese, Hibernation of, 261.
Perroncito, E., Cercomonas intestinalis,
76.
Pescarolo, ms

Pathogenic Bacterium
found in Tetanus, 105.

Petals, Anatomy and Chemistry of, 542.

Petiole of Dicotyledons, 408.

Petit, E., Chlorosis, 671.

, Petiole of Dicotyledons, 408.

Petri, R. J., Nitric Acid in Gelatin, 457,
603.

—, Simple Apparatus for Injecting
Fluids for Bacteriological Purposes,
308.

Petrographical Tables, Rosenbuscl’s, 603.

Petrological Microscope, Crouch’s, 113.

——,, Dick and Swift’s Patent, 432.

—— ., Reichert’s, 113.

Petromyzon, Preparing Egzs of, 704.

Pettigrew, J. B., On the Use of the
Camera Lucide, 702.

Pezizee causing Cankers in Coniferz, 263.

Pfeffer, W., Botanical Microscope, 272.

, Process of Oxidation in Living Cells,

550.

, Reduction of Silver in the living-
cell, 539.

Pfeiffer, A., Microscopical
Bacteriology, 716.

, Photomicrographic Atlas of Bacteri-
ology, 107.

Pfuhl, —., Spore-formation in the Bacillus
of Typhoid Fever, 269.

Pheodermatium, 676.

Pheosporezx, Chromatophores of, 95.

Phagocytes, Doctrine of, 267.

Phanerogamia, Anatomy and Physiology
of. See Contents, xxi. °

Phascolosoma Gouldii, Reproductive Organ
of, 518.

Philibert, —, Peristome of Mosses, 257,
673.

Phisalix, C., Study of a Human Embryo,
362

Atlas of

Pholas dactylus, influence of light on, 39.

, Luminous Phenomena in, 736,

Phoronis australis, Anatomy of, 740.

-—— Buskii, 376.

, New Species of, 644.

Phosphorescence of Agaricus olearius, 564.

of Pleurotus olearius, 426.

Phosphorescent Infection of Talitrus and
other Crustacea, 749.

Mushroom, 565.

Photo-position of Leaves, 91.

F bolgesepule Lenses, Construction of,

| Photography,

INDEX.

New - Application of, to
Botany, 839.

Photolysis in Lemna trisulea, 79.

Photomicrographie Apparatus, 850.

Atlas of Bacteriology, 107.

Phragmites communis, Dicsmose through
the Cellulose-pellicle of, 539.

Phreoryctes, Anatomy and Histology of,
755.

Phronima sedentaria, Male of, 753.

Phycoerythrin, 258.

Phycomyces, Heliotropism of, 681.

Phycopeltis, 786.

Phyllactidium, 419, 786.

Phylline Hendorfii, Anatomy of, 521.
Phyllotaxis, Relationship of the Twisting
Action of the Vascular Bundles to, 88.

Phylloxera and Chermes, 379.

Phymosoma varians, 642.

Physaloptera, 518.

Physapoda, Anatomy and Biology of, 203.

Physcia parietina, Synthesis of, 561.

Physiology of Growth, 548.

Piccone, A., Connection of the geo-
graphical distribution of Algze with
the chemical nature of the substratum,
555.

Pickering, J. W., Proamnion and Amnion
in Chick, 726.

Piersol, G. A., Continental Microscope,
276.

, Imbedding in Paraffin, 462.

Pigment of Euglena sanguinea, 768.

Pigments of Fungus, 560.

Pilinia, 421.

Pilophorus, 680.

Pilularia, Development of, 254.

——-, Sporocarp of, 785.

Pinus halepensis, Bacillar Tumour on,
243, 546.

Strobus, Uredinez of, 564.

Pirotta, R., Fertilization of Amorpho-
phallus Rivieri, 411.

, Starch in the Epiderm, 773.

Pitchers of Sarracenia, 408.

Pittion, —., New Rapid Process for
Staining Bacillus tuberculi, 468.

Piutti, A., Respiration of the Ova of
Bombyx, 635.

Placenta in Dog, Development of, 726.

of Inuus nemestrinus, 726.

of Rabbit, 28, 621.

| Placentation of the Dugong, 726.
| Planta, A., Composition of the Tubercles

of Stachys tuberifera, 665.

Plants, Descending Current of Water in,
548.

Plasmodium malariz, Intimate Structure
of, 651.

Plastic Reconstruction, Cutting Micro-
scopical Objects for the purpose of, 146.

Plate, L., Aegyria oliva, 74.

, Luminosity of Noctiluca miliaris,

236.

INDEX.

Plate, L., New Vorticelline, 74.

Plate Modelling Method, or Plastic Re-
construction of Object, 144.

Plateau, F., Vision of Arthropods, 202.

Platner, G., Import of Polar Globules,
365.

——., Investigation of Cell-structure, 459.

Polar Body Formation in Aulas-

tomum, 755.

, Role of the Accessory Nuclear Body
in Secretion, 625.
—, Spermatogenesis

743.

——, Structure of the Cell and Phenomena
of its Division, 366.

Platyhelminthes. See Contents, xvii.

Plaut, H., Prevention of Cultivations from
Drying, 459.

Pleomorphism of Bacteria, 795.

Pleospora herbarum, Polymorphism of,
425.

Plessis, G. du, Otoplana intermedia, 643.

Pleurosigma angulatum, Structure of, 166,
566, 812.

Pleurotus olearius, Phosphorescence of,
426.

Plowright’s (OC. B.), British Uredinew and
Ustilaginez, 424.

Plumatella, Formation of Statoblasts, 377.

Plymouth, Marine Oligocheeta, 515.

Pelagie Copepoda, 753.

Sound, Nudibranchiate Mollusca, 737.

Pneumonia of Lambs and Calves, Micro-
organisms of, 270.

Pocock, R. I., Myriopoda of Mergui Archi-
pelago, 507.

Podocoryne, Origin of Female Generative
Cells in, 231.

Podophrya from Calcutta, 768.

Poison-apparatus of Mosquito, 51.

Poisons, yeast, 108.

Polar Bodies, Number of, 193.

— Globules, Import of, 365.

in Cirripedes, Formation and
Number of, 385.

—— —— in Eggs of Insects, Formation
and Fate of, 502.

——, Number of, in Eggs of Bees, 634.

Polar-Body, Formation in Aulastomum,
755.

Polarity and Dorsiventral Structure of
Plants, Influence of External Agents on,
668.

Polarizer, Ahrens’ Modification of Dele-
zenne’s, 276.

Polarizing Apparatus for the Microscope,
610, 617.

Poléjaeff, N., Korotnewia desiderata and
the Phylogeny of Horny Sponges, 649.
Poli, A., Formation of Calcium oxalate in

Plants, 774.

——, Imbedding in Glycerin Soap, 835.

—,, Kaiser’s Gelatin for arranging micro-
scopical preparations in series, 153.

——,, Notes on Microscopy, 294.

in Lepidoptera,

—

883

Poli, A., The Microscope and its theory,
294, 454.

Pollen of the Convolvulacez, 406.

of the Cycadew, 772.

Pollen-grains, 661.

-mother-cells, Demonstration of, 600.

-tubes, Demonstration of, 600.

Pollens, Medium for mounting, 602, 834.

Pollicipes and Anatifer, Tegumentary
Coverings of, 513.

Pollination by Lepidoptera, 667.

Pollinoids of Florides, 674.

Polycheeta of Dinard, 55.

Polydesmus petalicolor, sp. n., 265.

Polygonum, Dimorphism of, 781.

Polymorphism of the Leaves of Abietines,
245.

Polyodontes maxillosus, 754.

Polypore, Poroptyche, a new genus of,
565.

Polysiphonia, Frond of, 556.

Polyxenus lagurus, Anatomy of, 637.

Polyzoa. See Bryozoa, Contents, xiii.

Pompilide, Male Copulatory Apparatus of,
205.

Poplar, Lombardy, parasitic fungus on, 681.

Porifera. See Contents, xix.

Poroptyche, a new genus of Polypore, 565.

Porto Rico, New Algee from, 97.

Potato, Cultivation of Bacillus tuberculosis
on, 598.

Potonié, H., Sclerenchymatous Cells in the
Flesh of the Pear, 242.

Pouchet, G., Monstrous Larvee of Echinus,
392.

Poulton, E. B,, Lepidopterous Larvee, 206.

Powell and Lealand’s Apochromatie Con-
denser, 125.

Prantl, K., Parasitism of Nostoc, 567.

Prasiola, 793.

Prazmowski, A., Root-tubercles of Legu-
minose, 246.

Prentiss, A. N., Hygroscopic Movements
in the Cone-scales of Abietinez, 88.

President’s Address, 169, 317.

Prillieux, E., Bacillar Tumours of the
Olive and of Pinus halepensis, 546.

—, Ligneous Tumours in the Vine, 410.

, Parasitic Fungus on the Lombardy
Poplar, 681.

Primula with Anatropous Seeds, 663.

Prize offered to Medical Microscopists, 314.

Proceedings of the Society, 160, 315, 472,
608, 718, 845.

Prolification in the Hyphomycetes, 789.

Prosobranchiata, Neurology of, 372.

Proteromonas New, 768.

Prothallium of Lycopodium, 94.

Protista, Structure of Pylomata of, 238,

Protococcacew, Dicranochete, a new genus
of, 101.

——, Stomatochytrium, a new genus of
Endophytic, 565.

Protoneme of Mosses, Development of
Lichens on, 680.

884

Protophyta. See Contents, xxxi.

Protoplasm considered as a Ferment
Organism, 107.

— ,, Continuity of, in Plants, 601.

—, Movements of, 28.

See Cell-structure and Protoplasm.

Contents, xix.

, Structure of, 731.

Protoplasmic Movements, 78.

and their Relation to Oxygen
Pressure, 732.

Prototracheata. See Contents, xiv.

Prototremella, 564.

Protovertebree and the Segmentation of the
Vertebral Column, 362.

Protozoa. See Contents, xix.

Prouho, H., Reproduction of Ctenosto-
matous Bryozoa, 629.

Structure and Metamorphosis of
Larva of Flustrella hispida, 501.

Prunet, A., Foliar Vascular Bundles, 655.

Prussian Blue, Soluble, 463.

Pruyot, G., Formation of Stolons in Sylli-
dians, 642.

Psamathiomya pectinata, A New Dipterous
Insect, 180, 322.

Pseudopodia and Cilia, 237.

Pseudoscorpions, Anatomy of, 211.

Psilotum and Tmesipteris, 672.

Psorospermium Lucernarie, 75.

Pteris aquilina, Apospory in, 256.

Pteropoda. See Contents, xii.

Puccinia vexans, 681.

Pupa of Milkweed Butterfly, Changes of
internal organs, 379.

Purpura lapillus, Purple of, 627.

Puteren, V., Solid Media prepared from
Milk, 297.

Putrefaction, Development of Nitrogen in
414.

Pylomata of Protista, Structure of, 238.

Pyralide, New Genus of, 207.

Pyrosoma and Salpa, Alternation of
Generations in, 47.

, Structure of, 46.

Psychology of Protozoa, 766.

Q.

Quartz Wedge, Mode of using for estima-
ting the Strength of the Double Refrac-
tion of Minerals in thin slices of Rock,
286.

Quincke, G., Movements of Protoplasm, 28.

Quinn, EH. P., Mounting in Fluosilicate of
Soda, 716.

Vise

Rabbit, Formation of Placenta of, 621.

—, Neurenteric Canal in, 29.

, Placenta of, 28.

Rabenhorst’s Cryptogamic Flora of Ger-
many (Fungi), 101.

— (Musci), 95.

—-— —— (Vuscular Cryptogams), 553.

INDEX.

Raciborski, M., New Myxomycetes, 683.

Radial Connection of the Vessels and
Wood-parenchyme, 83.

Radoszkowski, —., Male Copulatory Ap-
paratus of Pompilide, 205.

Rafter, G. W., Volvox globator, 677.

Raillet, A., Filaria medinensis in Animals,
756.

Rana fusca, Development of Germinal
Layers and Notochord in, 30.

Ranunculus aquatilis, Case of Germina-
tion of, 89. :

, Nectarial Scales of, 662.

Ranvier, L., Histological Technique, 709.

Raphides in Monstera, 661.

Rathay, E., Distribution of the Sexual
Organs in the Vine, 249.

, Extrafloral Nectaries, 548.

Rats, Fecundation and Segmentation of
Ova, 490.

Raunkier, C., Myxomycetes of Denmark,
682.

Ravaz, L., Diseases of the Vine, 100.

, Structure of White Rot, 100.

Ravyenelia, 791.

Rawitz, B., Edge of Mantle of Acephala,
198.

Recknagel, G., Compendium of Experi-
mental Physics, 294. :

Red Sea, Red Organisms of, 236.

Rees, J. v., Preparing Musca vomitoria,
299. S

Reiche, K., Winged Stems and Decurrent
Leaves, 244.

Reichert’s (C.) Petrological Microscope,
113.

Reinhard, W., Development of Germinal
Layers, Notochord, and Mid-gut in
Cyprinoids, 31.

Reinitzer, F., Composition of Tannin,
773.

Reinke, J., Chromatophores of Pheo-
spores, 95.

, Tilopterideze, 419.

Renal Apparatus of Pulmonate Gastropods,
Anatomy and Development of, 628.

Renard, A., Value of the Microscopic
Analysis of Rocks, 310.

Rendle, A. B., Vesicular Vessels of the
Onion, 775.

Rennie, E. H., Colouring Matter of Drosera
Whittakeri, 240.

Report of the Council, 315.

Reproduction of Phanerogamia. See Con-
tents, XXiv.

Reserve-substances, Accumulation of, in
Trees, 242.

Resistance of plants to causes which alter
the normal state of life, 89.

Respiration, Changes of Substance and
Force connected with, 671.

of Phanerogamia. See Contents, xxvi.

Respiratory Organs of Decapodous Crus-
tacea, Ancestral Development of, 381.

Rhamnacee, Reservoirs of Gum in, 241,

INDEX.

Rhamphospora, a new genus of Ustila-
gines, 423.

Rhea americana, Spiroptera alata, a new
Nematode found in, 756.

Rhinanthaces, Haustoria of, 665.

, Vegetative Organs of, 410.

Rhinoscleroma, Staining Bacilli of, 307.

Rhizocarpex, Systematic Position of, 254.

Rhizoctonia, 681.

Rhizome, Abnormal Formation of, 780.

of Monocotyledons, Vascular Bundles
in, 243.

Rhizopod Fauna of Bay of Kiel, 769.

— of Gulf of Genoa, 237.

— Shells, Structure of, 768.

Rhopalodina lageniformis, 392.

Rhysodide, Mouth-organs of two species
of, 208.

Rhytisma acerinum, Dissemination of the
Spores in, 426.

Rice, Fungi parasitic on, 788.

Richard, J., Fresh-water Fauna of Green-
land, 367.

Richet, C., Staphylococcus pyosepticus,
269.

Ridley, H. N., Foliar Organs of a new
species of Utricularia. 245.

Rietsch, —., New Pyogenetie Bacillus,
684.

“Ringing,” Influence of, upon Growth,
781.

Robert, E., Hermaphroditism of Aplysia,
373

Robertson, C., Flowers and Insects, 781.

——, Zygomorphy and its Causes, 85.

Robinson’s (J., & Sons) Photomicrographic
Cameras, 128.

Rocks, Value of the Microscopic Analysis
of, 310.

Rockwood, G. G., Detecting Alterations
in Manuscripts, 717.

Rodewald, H., Changes of Substance and
Force connected with Respiration, 671.

Rodier, E., Sphero-crystals, 773.

Roeser, P., Two Infusorians from the Port
of Bastia, 398.

Rogers’ Eye-piece Micrometer, 443.

, KF. A., Preparation of Drug Sec-

tions for Microscopical Examination,

709.

, W. A., The late Chas. Fasoldt, 829.

Rohde, E., Nervous System of Amphioxus,
36

Rolland, —., Blastomyces, 786.

Rollett, A., Siructure of Muscle, 35.

Romanes, G. J., Psychology of Protozoa,
766.

Root and Stem in Angiosperms, Mode of
Union of, 84.

— of the Filicine, 785.

Root-tubercles of Leguminosa, 246.

Roots, Aerating, 780.

—,, Lateral, of Monocotyledons, 547.

- ae ae Plants, Mechanical System

in, 659.

1889.

885

| Roots of Galega officinalis, Tubercles on,

546.

| —— of Grasses growing in Water, Modifi-

cations in, 666.

—— of Trees, Periodical Activity of the
Cambium in, 549.

Rosa, D., Indian Perichxtidsx, 220.

, New Genus of Eudrilide, 220.

Rosa, Odour of the Glands in, 775.

Rose, J. N., Achenes of Coreopsis, 778.

Rose, Ovaries and Achenes of, 778.

——, Perfume of, 774.

Roseler, P., Increase in thickness of the
Arborescent Liliacese, 657.

Rosenbusch, H., Microscopical Physiology
of the Rock-making Minerals: an aid to
the Microscopical Study of Rocks, 295.

, Petrographical Tables, 603.

Rosenyinge, L. K., Frond of Polysiphonia,
556.

——,, Influence of External Agents on the
Polarity and Dorsiventral Structure of
Plants, 668.

Rosoll, A., Two new Copepods parasitic on
Echinoderms, 54.

Ross, H., Assimilating Tissue and Peri-
derm in leafless plants, 541.

Ross’s (A.) Screw and Pinion Coarse- and
Fine-Adjustment, 691.

Rosseter, T. B., Cysticercoids in the body-
cavity of Cypris, 322.

Rossiiskaya, M., Development of Amphi-
poda, 510.

Rostrup, E., Rhizoctonia, 681.

Rostrupia, a new genus of Uredinex, 790.

Rotation of Protoplasm, 402.

Rotifer, New, 227.

——, Parasitic, Discopus synapte, 60.

Rotifera, 759.

——, American, 523.

from Geneva, 59.

Parasitic in Sphagnum, 523.

Roule, L., Development of Coelom in En-
chytroeides Marioni, 387.

——, Early Development of Blastodermic
Layers in Isopoda, 639.

, Influence of Nervous System of
Annelids on Symmetry of Body, 514.

——., New Species of Phoronis, 644.

Roumegueére, —, Disease of Chestnut-trees,
562.

Rousselet, C., New Rotifer, 227.

Roux, E., New Rapid Process for Staining
Bacillus tuberculi, 468.

——, Photomicrography with Magnesium
Light, 129.

—, Preventive Inoculations, 797.

Rovelli, G., Embryology of Cestodes, 389.

, New Acarid, 638.

Royston-Pigott, G. W., Anti-diffraction
Micrometer, 277.

—, Microscopical Advances, 136, 295,
454, 702.

» Microscopical Imagery, Solar Splen-

dours, 454, 829.

3 Q

886

Royston-Pigott, G, W., New Apochromatic
Test, 454.

, Obituary Notice, 703.

Roze, —., Azolla filiculoides, 417.

Ruminants, Micro-organisms in Paunch of,
651.

Ruppia, Tubercles of, 547.

Rusts, Subepidermal, 791.

Ryder, J. A., Byssus of young of common
Clam, 375.

——, Volyox minor, 786.

8.

S. D., Microscopist’s Table, 159.

Sablon. See Leclere du.

Saccharine Crystals, Production and Pre-
servation of, 835.

matters of Fungi, 677.

Saccharomyces Allii, sp. n., 265.

—— apiculatus, 98.

, Cotemporaneous action of different
kinds of, 790.

— lactis, 426.

Sadebeck, R., Fungus-parasites of the
Alder, 680.

——, Preserving-fluids for Fleshy and
Succulent Plants, 154.

Saffron, Staining Muscle with, 467.

Saint-Joseph, —, Polycheeta of Dinard, 55.

Saint-Loup, R., Anatomy of Aplysia, 195.

, Hermaphroditism of Aplysiz, 373.

—,, Polyodontes maxillosus, 754.

Saint-Rémy, G., Brain of Araneida, 211.

of Peripatus, 745

Salkowski, E., Ferment from putrefactive
Bacteria, 104.

Salpa and Pyrosoma,
Generations in, 47, 629.

——, Branchial Homologies of, 376.

Salt-water Sponges, Collecting, 456.

Sanders, A., Preserving Nervous Systems
460.

Sanfelice, F., lodized Hematoxylin, 837.

Sanna-Salaris, G., Glischrobacterium, 571.

Sap, Movement of, in Wood, 670.

Saposchnikoff, W., Formation of Starch out
of Sugar, 783.

Saprolegniee, 99.

Saprolegniacex, Structure of, 678.

Saprophytic development of Parasitic
Fungi, 682.

Sarcinee of Fermentation, 106.

Sarcoma, Staining differences in resting
and active nuclei in, 712.

Sarcosporidia in Muscles of Paleemon, 76.

Sarracenia, Pitchers of, 408.

Sauvageau, ©., Intercellular Protoplasm,
239.

, Mechanical System in the Roots of

Aquatic Plants, 659.

, Staining of Vegetable Tissues, 306.

Saxifragaceze, Stem of, Strengthening Ap-
paratus in, 776.

Alternation of

INDEX.

Scenedesmus, 427.

Scent of Flowers, 253.

Schaffer, C., Histology of Insects, 633.

Schalfejeff, P., Anatomy of Clione limacina,
WO

Schaub, R. y., Anatomy of Hydrodroma,
51.

——, Marine Hydrachnida, 509.

Schertfel, A., Glands on the Rhizome of
Lathrea, 89.

Schewiakoff, W., Eyes of Acalephe, 532.

, Holotrichous Infusoria, 767.

——,, Investigation of Infusoria, 833.

-—, Karyokinesis in Euglypha alveolata,
112).

——, Preparing Megastoma entericum,
301

Schicht, A., New Cases of Mycorhiza,
422.

Schiefferdecker, P., 305.

Schill, —., Flask Cultivations, 458.

——, Preserving Plate and Tube Culti-
vations, 458.

——, Staining Tubercle Bacilli on Slides,
602

——, Wafers for Cultivation Purposes, 458.

Schimper, A. F. W., Epiphytic Vegetation
of the Tropics, 414.

Schistostega osmundacea, Shining of, 257. _

Schlumberger, C., Reproduction of Fora-
minifera, 771.

Schmidt and Haensch’s Apparatus for
Photographing the Tarnish Colours of
Tron Surfaces, 453.

, ., Secondary Medullary Rays, 777.

Schmidt’s Atlas der Diatomaceenkunde,
428. |

Schnetzler, J. B., Case of Germination of
Ranunculus aquatilis, 89.

, Resistance of plants to causes which

alter the normal state of life, 89.

, Rotation of Protoplasm, 78, 402.

Schénland, 8., Morphology of the Mistle-
toe, 248.

Schott, O., On glass-melting for optical
and other scientific purposes, 703, 831.

Schott & Co., New optical glass, 136.

Schottelius, M., Nucleus or nucleoid bodies
of Schizomycetes, 429.

Schrodt, J., Opening of the Anthers of
Cycadee, 86.

Schuberg, A., Grassia ranarum, 771.

Schultze, E. A., Fossil Marine Diatoms,
566.

— , O., Development of Germinal Layers
and Notochord in Rana fusca, 30.

Schulz, A., Cleistogamic Flowers, 412.

, H., Yeast-poisons, 108.

Schulze, F. E., Epithelial Glands in
Batrachian Larvee, 190.

Schumann, K., Borragoid Inflorescence,
663.

——, Obdiplostemonous Flowers, 661.

Schunck, E., Chemistry of Chlorophyll, 79,
Dau

INDEX.

Schiitt, F., Phycoerythrin, 258. 1
Schiitz, J., Staining and Detection of
Gonococci, 712.

Schwarz, E., Embryonic Cell-division, 624. /

Schwendener, 8., Stomates of Graminez
and Cyperacez, 545.

|
|

Scientific instruments at the International |

Exhibition at Brussels, 136.

Scinide, Amphipod Family of, 512.

Sclerenchymatous Cells in the Flesh of
the Pear, 242.

Sclerotinie of Vaccinium, 263.

Scottish Microscopical Society, 830.

Sea-Urchins, Boring, 760.

Secretion, Role of the Accessory Nuclear
Body in, 625.

Secretion-reservoirs, 241.

Section-cutting. See Contents, xxxvi.

-fixing, 839, 840.

Sections, Easy Method for “ Photograph-
ing,” 133.

, Serial, Manipulation of, 840.

Sedum spectabile, Formation of Starch in
the Leaves of, 541.

Seed of Geraniacez, Integument of, 88.

of Papilionacez, Intercellular Spaces
in Tegument of, 775.

Seeds and Fodder, Bacteria of, 268.

——, Dormant, Nucleus in, 772.

‘—— of Capsicum, Epiderm of, 244.

—— of Euryale ferox, Germination of,
250.

—— of Nympheacee, 407.

— with ruminated Endosperm, Structure
and Development of, 87.

Seeliger, O., Alternation of Generations in
Salpze, 629.

Segmental and Genital Organs of Earth-
worm, 957.

Segmentation and Fecundation of Ova of
Rats, 490.

and Fertilization in Ascaris megalo-

cephala, 220.

in Double Organisms, 366.

Sehlen, —. v., Fixing Objects to Cover-
glasses, 308.

, Microscopical Examination of Urine
for Bacteria, 313.

Sehrwald, E., Paraffin Oven with simple
arrangement for maintaining a constant
temperature, 156.

Seibert’s Microscope, 805.

Sekera, E., Fresh-water Turbellaria, 757.

Selaginella, Chlorophyll-bodies of, 93.

Selaginellacew, Endoderm of Stem of, 785.

Semmer, E., Micro-organisms of Pneu-
monia of Lambs and Calves, 270.

Semon, R., Development of Synapta
digitata, 62.

—, Homologies within the Echinoderm-
pylum, 759.

——, Secretion of Sulphuric Acid by
Marine Gastropods, 627.

Sense-Organs, Segmental of Arthropods,
501.

887

Senses and Habits of Crustacea, 748.

Sensory Organs, Abdominal, in Lamelli-
branchiata, 374.

Sepia, Development of. 370.

, Investigation of Ova of, 460.

| Serpulidee, Epidermis of, 515.

Sewell, P., Colouring-matter of Leaves
and Flowers, 80.

Sexual Organs in the Vine, Distribution
of, 249,

Sexuality among the Lower Alga, 260.

Shank, S. G. Cement Varnishes and
Cells, 470.

Sharp, D., Vision of Insects, 502.

Shattock, 8. G., Sears on the Stem of
Dammara robusta, 246.

Sheldon, L., Development of Peripatus
Nove Zealandiz, 210.

——, Maturation of Ovum in Cape and
New Zealand Species of Peripatus, 507.

| Shellac Injection for the Vessels of the

Eye, 150.

Shenstone, J. C., How to take Photomicro-
graphs, 455.

Sherborn, C. D., Additional Note on the
Foraminifera of the London Clay, 474,
483.

Sherman, W. W., Notes on Balsam Bottles,
842

Shimer, H., Examining a Shell-bark
Hickory Bud, 707.

——, Section-cutting in the Cold, 711.

Shipley, A. E., Macrosporium parasiticum,
791.

——, Phymosoma varians, 642.

Shore, T, W., Pro-amnion and Amnion in
the Chick, 726.

Sieve-plates in the Phloem of Angiosperms,
Development of, 405.

Silurian Cephalopods, Structure of, 369.

Silver Nitrate, Reaction of Elastic Fibres
with, 137.

——, Reduction of, in the liying-cell,
539.

Simmons, W. J, Examining Ants for
Intestinal Parasitic Infusoria, 461.

——, Holotrichous Infusoria parasitic in
White Ants, 399.

——, Magnification in Photomicrography,
700.

, Podophrya from Calcutta, 768.

Siphonocladacez, Influence of Position on
the Morphological Development of
some, 421.

Siphonophora, ‘Challenger,’ 394.

of Canary Islands, 530.

—,, Organization and Phylogeny of, 764.

Skertchly, 8. B. J., Butterflies’ Enemies,
504.

——. Habits of certain Borneo Butterflies,
744.

Sladen, P. W., Asteroidea of the Voyage
of the ‘ Challenger,’ 645.

Slide-rest for the Manipulation of Serial
Sections, 840.

a Q-2

888

Slides, Finishing, 471.

Sluiter, C. P., Remarkable Actinian, 530.

Smiley, C. W., White’s Botanical Prepara-
tions, 707.

Smith, E. A., New Genus of Parasitic
Mollusea, 374.

——., E. F., Peach-Yellow, 792.

, T. F., Fine grating in Pleurosigma

angulatum, 166.

On the Abbe Diffraction-plate,

2 7
702.

——, ——, Photomicrographs, 320.

, , Ultimate Structure of the
Pleurosigma Valve, 566, 812, 848.

Snails, Fertilization by, 548.

, Protection of Plants against, 93.

Snow, Bacteriology of, 572.

Soap, Glycerin, Imbedding in, 835.

Soda, Fluosilicate of, Mounting in, 716.

Séderstr6m, E., Desmarestia aculeata,
675.

Soil, Relation between the formation of
Tubercles and the presence of nitrogen
in, 251.

Solen pellucidus, Swelling of Foot of, 201.

Solenophorus, Structure ot, 523.

Solereder, H., Comparative Anatomy of
the Aristolochiaces, 660.

Solger, B., Demonstrating Mitosis in Mam-
malia, 831.

Solms-Laubach, Graf zu., Penicilliopsis,
a new genus of Ascomycetes, 424.

, Ustilago Treubii, 99.

Somomya erythrocephala, Preparing the
Brain of, 301.

Sonsino, P., Helminthological Notices, 758.

, Nematode in Blood of Dog, 58.

Sorauer, P., Mildew of the Apple, 563.

, “ Tan-disease ” of Cherries, 551.

Sorokin, W., Algophaga pyriformis, 106.

, Polydesmus petalicolor, sp. n., 269.

, Saccharomyces Alii, sp. n., 265.

——, Sorosporella Agyrotidis g. et sp. n.,
266.

Sorosporella Agrotidis g. et sp. n., 266.

Soulier, A., Epidermis of Serpulide, 515.

Southern Seas, Coelenterata of, 67.

Soyka, —., Development of Pathogenic
Microbes on Media previously exhausted
by other micro-organisms, 458.

—, Rice-milk, a new solid culture
medium, 137. :

Species, Origin of, 31.

Spectrum-analysis of the
Flowers, 403.

Spencer, W. B., Anatomy of Megascolides
australis, 216.

Spermatogenesis, 364.

— during Inanition, 728.

— in Lepidoptera, 743.

— in Mammals, 623.

—— in Man, 365,

in Ostracoda, 640.

Spermatozoa, Double Forms of, 371.

, Human, Observations on, 190

Colours of

INDEX.

Spermatozoa, Penetration of, into Ova of
Frog, 727.

, structure of, 36.

Spheerites, 81.

Sphzerococcus, Reproduction of, 258.

Spheropsidez, Germination of the Spores
of, 263.

Sphagnaces, Colouring-matter of, 674.

Sphagnum, Acutifolium-Section of, 94.

, Helotium parasitic on, 263.

, Rotifers Parasitic in, 523.

Sphero-crystals, 773.

Spines of Crustacean Zocexe, Function of,
748.

Spinnerets of Myriopoda, 507.

Spirilla, Staining Flagella of, 837.

Spirogyra, Conjugation of, 786.

, Contraction of the Chlorophyll-bands
of, 557.

Spiroptera alata, a new Nematode found
in Rhea americana, 756.

Sponges, collecting salt-water, 456.

See Porifera, Contents, xix.

Spongilla, Metamorphosis of Larva of,
765.

Spongocladia, 557.

Spore-formation in the Bacillus of Typhoid
Fever, 269.

Spores of Fungi, dispersion of, by Insects,
792.

of Spheeropsidez, Germination of, 263.

Sporids of Lichens, 97.

Sporocarp of Pilularia, 785.

Springer, F., Crotalocrinus, 228.

, Ventral Structure of Taxocrinus and
Haplocrinus, 228.

Stachys tuberifera, Composition of the
Tubercles of, 665.

Stage, Adjustable Safety, 121.

Stahl, E., Protection of Plants against
Snails, 93.

Staining. See Contents, xxxvi.

Stamati, G., Monstrosity in a Crayfish, 213.

Stamens and Styles, Spontaneous Move-
ments of, 251.

——, Elastic, of Compositee, 544.

—— of Caryophyllacex, Glands on, 544.

, Sensitive, in Composite, 778.

Staphylococcus pyogenes aureus, Structure
of, 270

pyosepticus, 269.

Starch, Formation of, from Organic Solu-
tions, 414.

, ——, in the Leaves of Sedum specta-
bile, 541.

—— ——,, out of Sugar, 783.

in the Epiderm, 773.

Starches, New Medium for Mounting, 602,
834.

Starfish, Large, 529.

Starr, T. W., Preparing and Mounting
with Pressure Insects entire, as Trans-
parent Objects, 705.

Statoblasts, Formation of, in Plumatella,
377

INDEX.

Steam Funnel, Stein’s, 157.

Steam-generator for Microscopical Tech-
nique, Garbini’s Small, 155.

Stebbing, T. R. R., Amphipoda of the
‘Challenger,’ 383.

Stedman, J. M., Development of Actino-
spherium eichhorni, 400.

Stein’s (L. v.) Steam Funnel, 157.

Steinbrinck, C., Connection of the Direction
of Hygroscopic Tensions with the Struc-
ture of the Cell-wall, 403.

Stelospongus flabelliformis, 233.

Stem and Leaf of Utricularia, 780.

— and Root in Angiosperms, Mode of,
Union of, 84.

of Dammara robusta, Scars on, 246.

—— of Saxifragacex, Strengthening Ap-
paratus in, 776.

Stems, Winged, and Decurrent Leaves,
244,

Stenopus, Life-history of, 752.

Stenzel, G., Tubicaulis, 553.

Stephani, F., New Hepatice, 257.

Sterns, E. E., “ Bulblets” of Lycopodium
lucidulum, 255.

Stigmata of Hymenoptera, 505.

Stipules, Homology of, 779.

Stockmayer, 8., New Genus of Desmi-
diacex, 420.

Stokes, A. C., Microscopical Work for
Amateurs, 136.

——.,, New Peritrichous Infusoria from the
Fresh Waters of the United States, 474,
477.

, Pollen of the Convolvulacex, 406.

Stomates of Conifers, 546.

, Opening and Closing of, 780.

Stomatochytrium, a new genus of En-
dophytic Protococcacez, 565

Stossich, M., Helminthological Notes, 521.

——, Physaloptera, 518.

——, The Species of Distomum in Am-
phibians, 521.

Strasburger, E., Growth of the Cell-wall,
538.

Striibing, O., Stomates of Conifers, 546.

“Struggling Microscopist,” 450.

Struvea, 260.

Stuart Microscope, 321.

Stuhlmann, F., Fresh-water Fauna of East
Africa, 494, 733.

Stur, D,, Calamariex, 673.

Styles and Stamens, Spontaneous Move-
ments of, 251.

Stysanus, 788.

Suberized Membranes, Optical Properties
of, 78.

Substage, elementary centering, 846.

Substratum, Influence of, on the Growth of
Plants, 90.

Subterranean Swellings, Formation of, in
Eranthis hyemalis, 247.

Sudduth, W. X., Artistic Photomicro-
graphy attained, 698.

Sugar, Formation of Starch out of, 783.

889

Sulphuretted Hydrogen, Bacteria which
produce, 567.

Sulphuric Acid, Secretion of, by Marine
Gastropods, 627.

Sutton, J. B., Evolution of the Central
Nervous System of Vertebrata, 187.

Swift’s (J.) Mineral Microscope, 274.

——, Photomicrographic Apparatus, 283.

Syllidians, Formation of Stolons in, 642.

Symbiosis of Algze and Animals, 767.

Synapta digitata, Development of, 62.

Synchytrium alpinum, 787.

Synedra pulchelJa, Ktz., var. abnormis, 566.

Synthesis of Lichens, 679. '

he

Tacke, B., Development of Nitrogen in
Putrefaction, 414.

Tenia cucumerina, Intermediate Host of,
226.

Tafani, A., Fecundation and Segmentation
of Ova of Rats, 490.

Talitrus and other Crustacea, Phosphores-
cent Infection of, 749.

** Tan-disease” of Cherries, 551.

Tangl, F., Relation between Cell-body and
Nucleus, 493.

Tannin, Composition of, 773.

in Plants, Mode of occurrence of, 541.

——,, New Micro-chemical reagent for, 606.

—.,, Physiology of, 654.

——,, Tests for, 606.

Tannin-vacuoles, 404.

Tapeworms with Perforated Joints, 225.
Tate, A. N., The Application of the Micro-
scope to Technological Purposes, 471.
Tauret, C., New Principle from Ergot of

Rye, Ergosterin, 240.
Tavel, —., Counting the Colonies in an
Esmarch Plate, 471.
Taxocrinus, Ventral Structure of, 228.
Taxodium, Leaf of, 664.
Taylor’s (J.) Oleomargariscope, 696.
—— (T.) Combination Microtome, 304.
Tealia and Bunodes, 763.

| Tedin, —., Primary Cortex in Dicotyle-

dons, 658.

Teitz, P., Relationship of the Twisting
Action of the Vascular Bundles to Phyl-
lotaxis, 88.

Teleostean Fishes, Reproduction and De-
velopment of, 491.

Teleutospores, Germination of, 678.

Tenison-Woods, J. E., Anatomy and Life-
history of Australian Mollusca, 626.

Tephrosia heterantha, Cleistogamous
Flowers of, 85.

Teredo, Morphology of, 498.

Termites, 50, 635.

, Replacement of King and Queen of,

Terpsinoé, Auxospore of, 794.
Terry, W. A., Movements of Diatoms and
Oscillaria, 566.

890

Test-ceils of Ascidians, Origin of, 740.

Tetanus, Pathogenic Bacterium found in,
105.

Tetraedron, 566.

Tetrastemma melanocephala, Preparing,
139.

Textile Workers, Practical Utility of the
Microscope to, 309.

Thallin, a new reagent for Lignin, 606.

Thanhoffer, L. y.. New Methods for Pre-
paring Nerve-cells, 598.

Thaxter, R., Cultures of Gymnosporan-
gium, 791.

Thelyphonus, Genital Organs of, 750.

Thiele, J.. Abdominal Sensory Organs in
Lamellibranchiata, 374.

Thoma’s (R.) Camera Lucida, 119.

Thomas, F., Synchytrium alpinum, 787.

Thompson, J. C., President’s Address to
the Liverpool Microscopical Society, 702.

——, J.P., Polarizing Apparatus for the
Microscope, 610, 617.

Thomson, J. A., Heredity, 619.

Thorpe, V.G., Description of a new species
of Megalotrocha, 610, 613.

Thouvenin, —, Strengthening Apparatus
in the Stem of Saxifragacesx, 776.

Thumen, F. y., Fungi parasitic on Rice,
788.

Thysanura and Collembola, 208, 299.
Tieghem, P. V., Doubling of the Endo-
sperm in Vascular Cryptograms, 254.

, Hydroleucites and Grains of Aleu-

rone, 239.

, Origin of Rootlets, 664.

——, Primary Liber-fibres in the Root of
Malvacez, 84.

Tiemann, F'., Chemical and Bacteriological
Examination of Water, 605.

Tigellum of Trees, 546,

Tilia, Bract in, 407.

Tilopteridese, 419.

Timber, Thin Sections of, 837.

Tmesipteris and Psilotum, 672.

Tee F., Branchial Homologies of Salpa,

76.

Tomaschek, H., Relationship of Bacillus
muralis and Glaucothrix gracillima,
108.

Tomes, A., Fly-catching Habit of Wrightia
coccinea, 412.

Toni, G. B. de., Chionyphe, 558.

, Integument of the Seed of Ge-
raniacez, 88.

——, Mycoidea, Hansgirgia, Phyllac-
tidium, and Phycopeltis, 419, 786.

——., Pilinia and Acroblaste, 421.

Topsent, E., Notes on Sponges, 396.

Tornaria in British Seas, 523.

Torék, L., Division of Red Blood-corpuscles
in Amphibia, 191.

Torsion, Violent Cause of, 253.

Toxic Principles of Fungi, 421.

ee of Insects, New Mode of Closing,

INDEX,

Trambusti, A., Hasy Method for “ Photo-
graphing” Sections, 133.

Transfusion-tissue of Coniferse, 657.

Treasurer’s. Account for 1888, 316.

Trécul, A., Order of Appearance of the
first Vessels in the Leaves of Humulus
Lupulus, and H, japonicus, 84.

, Root of the Filicine, 785.

Trees, Accumulation of Reserve-substances
in, 242,

, Development of Cork - wings on
certain, 84.

——, Diseases of, 551.

——, Fungi, Parasitic on, 788.

, Micro-organism found in the mucous

flux of, 795.

, Parasites on, 93.

——, Periodical Activity of the Cambium
in the Roots of, 549.

, Tigellum of, 546.

Trelease, W., Trimorphism of Oxalis, 667.

Trentepohlia, 420.

Treub, M., Protection of Buds in the
Tropics, 86.

-—., Prothallium of Lycopodium, 94.

Trenkmann, —, Staining the Flagella of
Spirilla and Bacilli, 837.

Trichiaces, Revision of, 325.

Trichine, Vitality of, 757.

Trichodina, Parasitic, 650.

Trilobites, Structure and Development of
the Visual Area in, 212.

Trimorphism of Oxalis, 667.

Tripolis, Marine, of the Valley of Metaurus,
Composition of, 102.

Tristomum elongatum, 758.

Trophilegic Function of Leaves, 670.

Tropics, Epiphytic Vegetation of, 414.

Trouessart, E. L., Marine Acarina of
Wimereux, 211,

, Marine Acarina of the Coasts of
France, 509.

Truffle, Parasitism of, 788. ;

Tschernich, F., Form of Pollen-grains,
661.

Tuberacese and Elaphomycetes, 679.

Tubercle Bacilli, Staining, 714.

—— ——, ——, on Slides, 602.

Tubercle Bacillus, New Bovine, 726

—— —— New Method for Staining, 713.

, Rapid Methods of Staining, in |
liquids and in tissues, 712.

Tubercles of Leguminosm, 247.

— of Ruppia and Zannichellia, 547.

— on the Roots of Galega officinalis,
546.

Relation between the formation of,
and the presence of nitrogen in the soil,
251.

Tuberculous infection of the Fowl Em-
bryo, 569.

Tubeuf, C. v., Fungi parasitic on Trees, 93,
788.

Tubicaulis, 553.

Tulasnella, 564.

INDEX.

Tulip-tree, Bud of, 245.

243.

Tumours, Ligneous, in the Vine, 410.

Tunicata. See Contents, xiii.

Turbeliaria, Fresh-water, 757.

Turgescence in Lamellibranchs, 375.

Turnbull, R., Water-pores in Cotyledons,
546.

Turner, Sir W., Placentation of the Du-
gong, 726.

Turpentine Oil, Solubility of Fat and
Myelin in, after the action of Osmic
Acid, 714.

Tyas, W. H., Methods of Hardening, &c.,
709.

Tylogonus Agave, 427.

Type-plates and arranged Groups
Diatoms, Preparation of, 152.

Typhlocyba rose, Galls produced on, 636.

Typhoid Fever, Spore-formation in the
Bacillus of, 269.

Tyroglyphus farinew, Accidental Parasitism
on Man, 509.

Tyrosin in Tubers of the Dahlia, 81.

Tyson, J., Ignorance of the Microscope
among Physicians, 703.

of

U.

Ulitny, J., Mouth-parts of Ancylus
fluviatilis and Velletia lacustris, 197.

Umbelliferze, Embryo of, 244.

——,, Septated Vittz of, 662.

Unicellular Algze, Culture, 137.

—— Beings, Functional Differentiations
in, 534.

Unio margaritifer, Distribution of, 376.

Unionide, Origin of, 498.

United States, New Peritrichous Infu-
soria from the Fresh Waters of, 447.

Upson, H. S., Carmine Staining of Nervous
Tissue, 148.

Urea, Permeability of Protoplasm for, 539.

Uredinez, Himalayan, 790.

of Pinus Strobus, 564.

, Rostrupia, a new genus of, 790.

Urie Acid, Demonstrating Presence of,
in Contractile Vacuoles of Lower Organ-
isms, 767.

Urine, Microscopical Examination of, for
Bacteria, 313.

Urocheta, Structure of, 218.

Urocystis, New, 266.

Urophlyctis Kriegeana sp. n., 561,

891

| Utricularia, Stem and Leaf of, 780.
Tumour, Bacillar, on Pinus halepensis,

Uropoda Krameri, Internal Anatomy of, 1. |

Urospora, 557.

Ustilaginee, 787.

Ustilago, Hermaphroditism of Lychnis
dioica when attacked by, 85.

Treubii, 99.

Uterus and Embryo, 489.

Utricularia, Foliar Organs of a new species
of, 245.

, Structure and Function of the Blad-
ders of, 545.
Utriculariacex, Vegetative Organs of, 410.

Vs

Vaccinium, Sclerotinie of, 263.

Vacuole, Contractile, in Plants and Ani-
mals, Functions and Homologies of, 192.

Vacuoles in Alge, 674.

Vaillant, L., Natural History of Annelids,
642.

Vallentin, R., Psorospermium Lucernariz,
75.

Valvata piscinalis, Reproductive Organs
of, 498.

Van der Stricht, O., Fundamental Struc-
ture of Osseous Tissue, 731.

Van Dyck, F. C., Binocular Dissecting
Microscope, 275.

Vanhiifen, E., Semzostomatous
Rhizostomatous Meduse, 530.

Varnishes, Cement, and Cells, 470.

Vascular Bundles in the Rhizome of
Monocotyledons, 243.

Vegetable Pathology, 105.

Preparations, Clearing and Staining
of, 306,

— Sections, Red Stain for, 307.

— Tissues, Staining of, 306.

Velenovsky, J., Fruit-scales of Abietines,
407.

Velletia lacustris, Mouth-parts of, 197.

Verson, E., Spermatogenesis, 364.

Vertebral Column, Segmentation of, and
the Protovertebrie, 362.

Vessels and Wood-parenchyme, Radial
Union of, 776.

Viala, P., Diseases of the Vine, 100.

and

| Vialleton, L., Development of Sepia, 370.

, Investigation of Ova of Sepia, 460.

Vibrio Metschnikovi, Natural mode of
infection of, 430.

—— Proteus, Variations of, 570.

Victoria, Seed of, 663.

— , Zoology of, 35, 194, 732.

Viguier, C., New Anthozoon, 393.

Villot, A., Circum-intestinal Cavity of
Gordii, 388.

——, Hypodermis and Peripheral Nervous
System of Gordiide, 388.

——, Ovary and Oogenesis of Gordius,
755.

Vine, Diseases of, 100.

——, Distribution of the Sexual Organs
in, 249.

——, Ligneous Tumours in, 410.

, New Fungi of, 100.

Vines, S. H., Opening and Closing of
Stomates, 780.

, Relation between the formation of

Tubercles and the presence of nitrogen

in the soil, 251.

892

Vines, 8. H., Staining the Walls of Yeast-
plant Cells, 714.

Vision, Disturbances of, consequent on
Microscopic Observation, 817.

— of Arthropods, 202.

— of Insects, 502.

Visual Area in the Trilobites, Structure
and Development of, 212.

Vize, J. E., Mounting Fungi, 461.

Vochting, H., Abnormal Formation of
Rhizome, 780.

, Photo-position of Leaves, 91.

Voeltzkow, A., Development in Egg of
Musca vomitoria. 505.

=, wie of Melolontha vulgaris, 506.

Voigt, A , Structure and Development of
Seeds with ruminated Endosperm, 87.

—,, W., Entocolax Ludwigii, Parasitic in
a Holot thurian, 197.

Volvox, 558.

— elobator, 677.

minor, 786.

Vorce, C. M., Hints on Mounting Objects
in Farrant’s Medium, 714.

Vorticelline, New, 74.

Vorworn, M., Preparing
Bryozoa, 138.

Vries, H. de, Contraction of the Chloro-
phyll-bands of Spirogyra, 557.

——-, Intracellular Pangenesis, 547.

os Permeability of Protoplasm for Urea,

9.

Vuillemin, P., Bacillar Tumour on Pinus
halepensis, 243.

, Parasitic Fungus on the Lombardy

Poplar, 681.

, Pezize causing Cankersin Conifere,

263.

, Relation of the Bacilli of the Aleppo
Pine to the Living Tissues, 797.

——, Tubercles of Leguminose, 247.

, Vegetable Biology, 671.

Vuylsteke, J., Cotemporaneous action of
different kinds of Saccharomyces, 790.

Fresh - water

W.

W., The scientific instruments and appa-
ratus at the Cologne Naturalists’
Meeting of 1888, 295.

Wachsmuth, C., Crotalocrinus, 228.

—,, Ventral Structure of Taxocrinus and
Haplocrinus, 228.

Wafers for Cultivation Purposes, 458.

Wagner, F. v., Asexual Reproduction of
Microstoma, 388.

——., J., Monobrachium parasiticum, 394.

, W., Eedysis of Spiders, 381.

Wakker, J. H., Contents of the Cell, 402.

Contributions to Vegetable Path-
ology, 105.

Waldeyer, W., Placenta of Inuus nemes-
trinus, 726.

Walker, C. H. H., New Cell, 716.

INDEX.

Wallace, A. R., Darwinism, 619.
Waller, S. H., Micro-chemical Methods
for the Examination of Minerals, 462.
Walsingham, Lord, New Genus of Pyra-
lidee, 207.

Warburg, O., Cancer of the Cinchona, 100.

Ward, H. M. , Lily Disease, 265.

Roi H., Micrometry by the Camera
Lucida, 702.

eece —., Rogers’ Eye-piece Micrometer,

Warnstorf, C., Acutifolium-Section of
Sphagnum, 94.

Wasmann, E., Function of Palpsin In-
sects, 742.

, Myrmecophilous Insects, 503.

Wasps, Observations on, 49.

Watase, 8., New Phenomenon of Cleavage
in Ovum of Cephalopods, 734.

, structure and Development of Eye
of ‘Limulus, 747.

Water, Absorption of, by Leaves, 671.

——, Bacteriological Examination of, 604,
605.

——, Conduction of, through Wood, 251.

——, Examining thin Films of, 843.

Water-pores i in CGotyledons, 546.

Waters, A. W., Bryozoa of New South
Wales, 629.

——, Ovicells of Cyclostomatous Bryozoa,
377,

r)

of Lichenoporee, 377.

—, Polyzoa of the Voyage of H.M.S.
‘ Challenger,’ 629.

Watson & Sons, Edinburgh Students’
Microscope, 695, 802, 850.

Webb, T. L., Dextrin Mucilage for Im-
bedding, 836.

Weber, EH. F., “ Notes on some Rotifera
from the neighbourhood of Geneva,”
59.

Weed, W. H., Diatom-beds of the Yellow-
stone, 794.

Wehmer, C., Calcium oxalate in Plants,
iil

Weir, F. W., Clearing recent Diatomaceous
Material, 302.

Weismann, A., Number of Polar Bodies,
193.

Weldon, W. F. R., Coelom and Nephridia
of Palzemon serratus, 749.

——, Functions of Spines of Crustacean
Zoceee, 748.

Welford, W. D., The “Indispensable
Handbook” to the Optical Lantern:
a Complete Cyclopedia on the subject
of Optical Lanterns, Slides, and Acces-
sory Apparatus, 295.

Wendt, A., Gunda ulve, 519.

Wenham, R. H., Large Apertures in
Microscopy, 702

Went, F. A. F. C., Vacuoles in Algze, 674.

Werminski, 1M Aleurone- -grains, 81.

West, W., List of fg from Mas-
sachusetts, U.S.A.,

INDEX.

West Indian Seas, Gastropoda and Scapho-
poda of, 735.

Westermaier, M., Physiology of Tannin,
655.

Wettstein, R. v., Extrafloral Nectaries in
Composite, 87.

Wevre, A. D., Anatomy of Bromeliacez,
411.

, Pericycle, 659.

Wheeler, W. M., Glandular Structure an
Abdomen of Embryos of Hemiptera,
745.

Whelpley, H. M., Action of Bleaching
Agents on Glass, 314.

, Iumination, 127.

——,, Microscopical Laboratory Notes, 471,
844.

—., Microscopy of the United States
Pharmacopeeia, 159.

White Rot, Structure of, 100.

White’s (W.) Botanical Preparations, 707.

Whitelegge, T., Collecting, Cleaning, and
Mounting Foraminifera, 709.

—, Method of Killing Zoophytes and
Rotifera, 709.

Whitman, C. O., Anatomy of Hirudinea,
O16,

——,, Solvent for the Gelatinous Envelope
of Amphibian Eggs, 138.

Wieler, A., Conduction of Water through
Wood, 251.

, Formation and Development of
Libriform Fibres, 776.

Wiesner, J., Descending Current of Water
in Plants, 548.

Wigand, A., Protoplasm considered as a
Ferment Organism, 107.

Wildeman, E. de, Mycoidea and Hans-
girgia, 419.

— _, Scenedesmus, 427.

——, Trentepohilia, 420.

——, Variation in Desmids, 557.

Wilks’ (G.) Improved Microtome, 836.

Wille, N., Apical cell of Lomentaria and
Champia, 556.

——, Bordered Pits of Conifers, 242.

——, Development of Tissues in Floridex,
555.

Willfarth, H., Obtaining of Nitrogen by
Graminex and Leguminose, 781.

Wilson, H. V., Development of Manicina
areolata, 231.

——, Occasional Presence of a Mouth and
Anus in Actinozoa, 761.

—, T., New Method of Determining
the Number of Micro-organisms in Air,
603.

— _, W. P., Aerating Roots, 780.

Wimereux, Marine Acarina of, 211.

Windle, W. 8., Fibres and Raphides in
Monstera, 661.

Winkler, A., Germination of the Hazel,
251.

Winogradsky, 8., Morphology and Physi-
ology of the Sulphur Bacteria, 567.

895

Wittrock, V. B., Binuclearia, 259.

Wood, Conduction of Water through, 251.

, Movement of Sap in, 670.

—, One-sided Hardness of, 669.

, Staining reagents for, 601.

Wood-parenchyme, Radial Connection of
the Vessels and, 83, 776

eee J. E. T. See Tenison-Woods,

26.
ba G. S., Selecting a Microscope,
OD:

Woronin, M., Sclerotinie of Vaccinium,
263.

Wortmann, J., Curvature of Growing
Organs, 782.

, Phenomena of Curvature, 92.

» Physical explanation of Irritation

curvatures, 413.

, Physiology of Growth, 548.

Wothtschall, E., On the microchemical
reactions of solanin, 159.

Woltke, G., Urospora, 557.

“ Wright” Collecting Bottle, Improved
Form of, 295.

Wright, L., Diffraction Theory, 811.

Wrightia coccinea, Fly-catching Habit of,
412.

24
Xanthophyllidrine, 240.
Xerotropism in Ferns, 256.
Xylol-dammar, 153.
Ne
Yeast-plant Cells, Staining the Walls of,
714.

-poisons, 108.
Yellowstone, Diatom-beds of, 794.
Yucca, Life-history of, 250.

Z.

Zabriskie, J. L., A Nest of Watch-glass
Covers, 471.

Zacharias, E., Formation and Growth of
the Cell-wall, 653.

——, O., Pseudopodia and Cilia, 237.

Zannichellia, Tubercles of, 547.

Zaslein, S., Varieties of Koch’s Comma
Bacillus, 269.

Zeiss. C., Death of, 135.

, Obituary Notice of, 295.

—., C. F., Obituary Notice of, 455.

—, R., Immersion Condenser of N.A.
1:60, 805.

Zeiss’s large Photomicrographic Appara-
tus, 278.

Zelinka, C., Parasitic Rotifer, Discopus
Synapte, 60.

Zentmayer, J., Death of, 135.

Zetinow, E., Chromo-copper Light-filter,
133, 700.

894

Ziegler, H. E., Origin of Blood of Verte-
brates, 725.

Zoceee, Crustacean, Function of Spines of,
748. .

Zoology of Victoria, 35, 732.

Zopf, W., Colouring-matters of Mycetozoa,
792.

Fungi parasitic on the lower Animals
and Plants, 423.

——,, Fungus-pigments, 560.

——, Oxalic Fermentation, 550.

INDEX.

Zoptf, W., Parasitic Monad, 399.

Zschokke, E., New Stains for Microscop-
ical Purposes, 147.

, F., Spiroptera alata, a new Nematode
found in Rhea americana, 756.

Zukal, H., Hymenoconidium, 427.

, New Type of Hymenomycetes. 99.

Zune, A., Medical and Pharmaceutical
Microscopy, 831.

Zygomorphy and its Causes, 85.

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Supplementary Number, containing Index, &c.

py 1889. Part 6a. DECEMBER.

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