—_——— 2} —_—__—_——_— sss ———————EE G~% 4 we? ies LD i ae aoe y ae Say fa! D 1 c } a eva A *) TAL hy TOURNAL ROYAL MICROSCOPICAL SOCIETY: CONTAINING ITS TRANSACTIONS AND PROCEEDINGS, AND A SUMMARY OF CURRENT RESEARCHES RELATING TO ZoDOoLoGeyvy AND BOTAN DT (principally Invertebrata and Cryptogamia), MICROSCOPY, &c. Edited by FRANK CRISP, LL.B., B.A., One of the Secretaries of the Society and a Vice-President and Treasurer of the Linnean Society of London ; WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND A. W. BENNETT, M.A., B.Sc., F. JEFFREY BELL, M.A., Lecturer on Botany at St. Thomas's Hospital, Professor of Comparative Anatomy in King’s College, 8. O. RIDLEY, M.A., of the British Museum, anv JOHN MAYALL, Joy., FELLOWS OF THE SOCIETY. ser. II—VOL. IIL PART 1. PUBLISHED FOR THE SOCIETY BY WILETANMS & NOKGAT E, LONDON AND EDINBURGH. TiO) ose bad y # ar A ina we art ry viay = Bc 9, Rees: JAN 20 1903 Hoval Microscopical Society. (Founded in 1839. Incorporated by Royal Charter in 1866.) The Society was established for the communication and discussion of observations and discoveries (1) tending to improvements in the con- struction and mode of application of the Microscope, or (2) relating to Biological or other subjects of Microscopical Research. It consists of Ordinary, Honorary, and Ex-officio Fellows. Ordinary Fellows are elected on a Certificate of Recommendation signed by three Fellows, stating the names, residence, description, &c., of the Candidate, of whom one of the proposers must have personal knowledge. The Certificate is read at a Monthly Meeting, and the Candidate balloted for at the succeeding Meeting. The Annual Subscription is £2 2s., payable in advance on election, and subsequently on Ist January annually, with an Entrance Fee of £2 2s. Future payments of the former may be compounded for at any time for £31 10s. Fellows elected at a meeting subsequent to that in February are only called upon for a proportionate part of the first year’s subscription, and Fellows absent from the United Kingdom for a year, or perma- nently residing abroad, are exempt from one-half the subscription during absence. Honorary Fellows (limited to 50), consisting of persons eminent in Microscopical or Biological Science, are elected on the recommendation of three Fellows and the approval of the Council. Ex-officio Fellows (limited to 100) consist of the Presidents for the time being of such Societies at home and abroad as the Council may recommend and a Monthly Meeting approve. They are entitled to receive the Society’s Publications, and to exercise all other privileges of Fellows, except voting, but are not required to pay any Entrance Fee or Annual Subscription. The Council, in whom the management of the affairs of the Society is vested, is elected annually, and is composed of the President, four Vice- Presidents, Treasurer, two Secretaries, and twelve other Fellows. The Meetings are held on the second Wednesday in each month, from October to June, in the Society’s Library at King’s College, Strand, Le (commencing at 8P.m.). Visitors are admitted by the introduction of ellows. In each Session two additional evenings are devoted to the exhibition of Instruments, Apparatus, and Objects of novelty or interest relating to the Microscope or the subjects of Microscopical Research. The Journal, containing the Transactions and Proceedings of the Society, with a Summary of Current Researches relating to Zoology and Botany (principally Invertebrata and Cryptogamia), Microscopy, &c., is published bi-monthly, and is forwarded gratis to all Ordinary and Ex- officio Fellows residing in countries within the Postal Union. The Library, with the Instruments, Apparatus, and Cabinet of Objects, is open for the use of Fellows every week-day except Saturday from 10 a.m. to 5 p.m., and on Wednesdays from 7 to 10 p.m. also. It is closed on Saturdays and during August. Forms of proposal for Fellowship, and any further information, may be obtained by application to the Secretaries, or Assistant-Secretary, at the Library of the Society, King’s College, Strand, W.C. a 2 p atron. HIS ROYAL HIGHNESS ALBERT EDWARD, PRINCE OF WALES, K.G., G.C.B., F.BS., &e. IO ae p ast-Presidents, Elected. Ricuarp Owen, O.B., M.D., D.C.L., LL.D., F.RS....... 1840-1 Jorn. bavpiny, Ph.D., VRS... 6.facie ae eetee > ee et sae 1842-3 nowas ant, WBS; ....<'s sa care ee ere miners sateen 1844-5 James Scott BowerBang, LL.D., F.R.S......... ..... 1846-7 eonoe ‘bugs, WARS. § .isc 5 pene ee as ee eee 1848-9 Aare (eAREE MT). ORS. Ssc evan sinters eit = 1850-1 Gkones JAOKSON, M.E-C.S.. 2. <2. coh e ee ooo aoe cine 1852-3 Wittiam Bensamin Carpenter, C.B.,M.D.,LL.D.,F.R.S. 1854-5 PSRGRGR SUADBOIUT so < s o/s.s. 120 Ancestral Form of the Chordata... .. os ae 629 Hypophysis cerebri in Vertebrata and T ee A a 630 Origin of the Follicular Cells 14 uu an une is x 630 Cells of the Ovarian Follicle Bee + 631 Bizzozero’s New Blood-corpuscle and Harris's T. hind Gee: puscular Element .. pec ho, TOM te 631 Colour-Markings of Pawnee ee aes ae ch 631 Retina of Ganoids ASarey LE x taint agree Moret are 632 Influence of Sea-water on Freshwater Animals, and of Fresh-water on Marine Animals .. 632 Development of Muscle-fibres and their union ous Ree Part 6 821 Cell Theory .. +» os snt® ook ® pa) ames mare emis 822 Xanthochroism of Parress os P tia nae’ precy |Y Se) bibaai eciene men 825 * In order to make the classification complete, (1) the papers printed in the ‘ Transactions,’ (2) the abstracts of the Bibliography, and (3) the notes printed in the Proceedings are included here. CONTENTS. ix PAGE Origin of the Individuality of Higher Animals .. .. . Part6 825 Occurrence of Chlorophyll in Animals.. s+ +6 ++ «8 826 Klein’s Elements of Histology «1 «+ «+ ++ #8 oe 49 827 B.— INVERTEBRATA. Anastomoses of the Striated Muscular Fibres of Invertebrates. Part 1 35 Apparently New Animal Type ecto oe .. Part 3 350 Chlorophyll of Animals.. +» «1 20 +s Meet sok ON ys 351 Division of Lower Invertebrates .. +1 +1 es ee wey 352 Structure of the Nucleus .. «+ « + «+ + « Part4 494 Radial and Bilateral Symmetry in Genes AG on oo JERR Gy (OBS) Symbiosis of Bryozoa and Actinie 4. «1 1 ee wey 635 Colouring Matters of Bile .. .. +6 ++ «» es +» Part 6 827 Mollusca. Digestion in Cephalopoda .. +» 2+ 6 +8 ee owe Part 1 36 Development of Bithynia tentaculata ., +. + «8 «6 4 36 Organization of Adriatic Chitons Se EEG a EnC Seiten eRe Ne 38 Generative Organs of Oysters .. 41 Development of Reproductive Organs of Behera Mollusca Part 2 192 Developmental History of the Prosobranchiata .. .. +» 4, 192 Norwegian Buccinide .. «+ ss 08 ee te ean 193 Sinisigera .. Oe in atobtveiens iat orca ten s(eSea as opegeess| staal 9 193 Green Colour of intars 2 5 194 Sucker on the Fin of the Heteropods ag a Sree Cha racteristic .. «. Bonet wecic co 60) oe 194 Growth of the “Molluscan Shell Bisa ett a Hoc Prop: MEDD. mcr eS ac 195 Chromatophores of Cephalopoda .. s+ ++ ++ «2 Part 3 352 Deep-Sea Solenoconcha 20 Agape woos ono: S ee 353 Vascular System of Naiade and Mytitide Bra tantis CO BO! baer 353 Generative Organs of the Oyster onMee Isat Snes Ons bs 354 Chromatophores of Cephalopoda ., 1 ss +1 +s we Part 4 494 Development of Chromatophores of ese sep Noss eg ars 494 Organization of Chitons .. +» +5 +4 oe on neg 495 Characters of Marionia BIW brn St tagte optic oh Phares stoku Mt ciclent 35 496 Digestive Processes in Cephalopoda «+ +1 s+ +4 + Part 5 636 Suckers of Cephalopods sick Wefepemgceh A Main Mey claMe Maier: 636 Development of Gastropoda .. +» «1 «5 +8 48 oe on 637 Liver of Gastropoda .. «» +8 «+: «8 «8 +8 8 499 637 Sensory Organs of Gastropoda .. +» «+ ++ +s 8 5 638 Pedal Nerves of Haliotis 1. «1 ++ 0» a8 we og 638 Pedal Glands of Mollusca .. «1 ss 00 ee newegg 639 Glands of Aplysia and allied Forms .. «» «1 6» ee 640 Sexual Characters of Oysters 1. «+ 66 se we we 640 Anatomy of the Marine iia 2c oc Paat 6 828 Differences between the Males and Females ae “ie Pearly Nautilus 5 BO ULIOD ae oo 830 Existence of a Shell m Notaralina: A ENED oonlarbs Bape dee 830 Molluscoida. Early Development of Salpide .. . RR er ed Betti pest! Compound Ascidians of the Bay of Naples. Beebe e Boe ci ea 42 New Diwision of Cheilostomatous Polyzoa .. +1 +s ++ 9 43 CONTENTS. New Type of Polyzoa—Cephalodiscus .. Vitality of Fresh-water Polyzoa .. Observations on Living Polyzoa . Individual Variation in Ascidians “6 Gemmation in Didemnide and Botryllide .. , Anatomy and Histology of Ciona intestinalis .. .. Mediterranean and Atlantic Bryozoa .. Development of Ova in Ascidians Structure of Ovary of Phallusiade Embryonic Development of Salpide Anatomy and Histology of Brachiopoda Testicardinia Ova of Ascidians .. « $a ot Oxycorynia, a new Syncsniain come sie x Calcarcous Stellates from off Deep-sea Organisms Hypophysis Cerebri in Vertebrata and Tunicata ag Origin of the Follicular Cells 4. 4s oe wt Symbiosis of Bryozoa and Actinie a) Gor) OO Development of Salpe and Pyrosomata .. us ae Structure of Anchinia .. Ad ao) MeGm ode” ac Development of Brachiopods BY lukisioa, W's MEMLeIe gers Structure of Tunicates.. om SCM “OD, Ore astoc Alteration of Ascidian Ova .. «4s se ee oe we Arthropoda. Olfactory Lobes in Vertebrates and Higher eae Structure of the Nucleus .. 6. «2 «6 Eyes of Arthropoda Results of Decapitation in ens oad i saapode Use of an adhesive substance by Arthropoda in jumping a. Insecta, Polar Cells of Insects .« +» oF « «2 oF of» Embryonic Development of the Ponbyoid a Asymmetry of the Nervous System in Larve .. .«. Vitality of Insects in Gases.. 1. 44 6s ue we Mouth-organs of Sucking Insects.. «1 +. «+ Scent-Organ of Papilio Hn! | Atha AO OLE Are ae Anatomy of Aphides ., «1 se « oe TMPyFIBe 1. oo oo 8 ce 56 08 8 Colour and Pattern of Insects .. 11 «+ +e . Partl » ” . Part 2 Lae) =) I ee ns ae" 3 oe sa) ear Development of the Excretory Generative Ducts in Insects, Anatomy and Development of the Ovary in Diptera .. Systematic Characters of the Labrum of Syrphide .. Genital Organs of the Orthoptera.. os Male Genital Appendages of the Saltatory Orticnens Circulation of Blood in the Larva of Hydrophilus. (Fig. Early Developmental Stages of Ovum in Insecta... Innervation of the Respiratory Mechanism in Insects Histology of Insect Wing-muscles «1 se veiw Flight of Insects 1. ss 00 00-= 02 «» | 2s ‘es Locomotion of Insects on Vertical Glass Surfaces .. Salivary and Olfactory Organs of Bees... we 35) 5 .- Parts PAGE 44 CONTENTS. xi PAGE Mimicry of Humming-birds by Moths... .. +» 41 +» Part 3 365 Histology and Development a WnSceist we toate aot | aera =! Le AFLe) 490 Markings on Podura Scales... ee ss 501 Relation of Light to Colour in Boaetier of Siar so on Jean) (azar Constancy and Methodic Habits of Insects in their Visits to Flowers .. SE osl Sammons 059 646 Rudimentary Wings m ‘the Galeonierea ac Aes are 647 Clasping Organs, accessory to Generation, in Ennis “5 648 Colour Preferences in Nocturnal Lepidoptera .. «+» +» 650 Fungus Parasitic on a Mature Coleopter .. .- +» ++ » 685 Flight of Insects .. .. a ge ay come cap Bac) ar On BS Antennary Rods of Vanessa Ip 9 832 B. Myriopoda. Existence of a Blastopore and Origin of the Mesoblast in Peripatus.. .. pad arte ly (OZ Formation of Prussic Aaa in a Mesos Beare “an eeere 53 Embryology of the Chilopoda «1 we wu we ee ee gg 54 Ventral Organ of Geophilus ar EE mee Serer’ walle Systematic Position of the rch etineds cy, Este sate tes barton ooo Anatomy and Development of Peripatus Capensis oe 366 New Species of Polydesmus with Eyes Ber Pine. Mice! = Reno irr 367 Dermal Appendages of Pes capt hats eles Meakbrero Ue Scolopendrella .. . Dj cqpdiican, beciet. aan 2 Ee OO Studies on the ipsa sen SOA al es meccracda ass haktoneed Development of Peripatus y. Arachnida. Observations on the Anatomy of the Oribatide. (Plates I. Onde TD ene sibling #8ks ioseieh. Saya a, oer ame ECR tas a Poison- Apparatus of Senge > 59 Snares of Orb-weaving Spiders Joh Ae tne? ceed cele ten as 55 Swiss Hydrachude .. . Jos Wise pecs Meee ae 38 56 Polymorphism and Parthonogenesi im ae Peeiicr a, iby beta ngon 7A Trombidium fuliginosum .. . Me 211 Pairing of Tegenaria guyonn — Soars in Wie “Wale Abdominal Sexual Region ae Re Re rr ei sas lz Anatomy of Pentastomum serene Seed suet sa -Com eer 503 Demodes phyllowdes, “se esl eel) eo) ny alas a Auditory Hairs of Arachnida .. .. « « « + Partd 692 Pentastoma Lari .. 1. «0 «» . Part 6 8395 6. Crustacea. Homologies of the Crustacean Limb .. .. « « « Partl 956 Characters of Nebalia .. .».» FAO SHEE tice ha o7 Nervous System of Paences CURIS hen ep DS epee 57 New Genus and Species of Lyncodaphnide .. Poets ar 58 Ecdysis of Apodemes in Crustacea .. «. «+ « « Part2 211 Blind Copepod of the Family aniacnene Bate ae re 212 Caprelide ..-.. | s- Seip eiyae ee ch oy eee een atonal Coloration of Idotea Peder. a re eS or 367 Larval Development of Phosichilidium Ragin i@ .. . Part 4 504 Relationships of the Malacostracua .. «sss ss ss 504 Xil CONTENTS. Circulatory Organs of Stomatopoda .. .. « Copepoda living in Molluscs and Ascidians .. .. «. American Parasitic Copepoda .. .. ss ss oe Integument of Decapod Crustacea 11 «1 ss oe Sense of Colour among some of the Lower aisahale . Part 4 ee ” Patt 5 New Cladocera of the English Lakes. ere XT. and IIL. ) Part 6 Researches on the Isopoda .. +. « Bo Moulting of the Shell in Limulus PRN Fine (00m “oC Vermes. Tubes of Sabellide So ck on Men co om Ot North-Sea Annelids .. ss co oc 08 oo ce Eclipidrilide a6 a © 00 Od OO co OL Ctenodrilus pardalis .. «s+ Distichopus .. «. 48. Oo) do ae Turriform Constr apne Dy Earthworms .. Hamingia arctica a5 Go oo 66 608 “66. Ge Anatomy of Prorhynchus .. oF «+ «s+ «8 Monograph on the Turbellarians .. Dinophilus apatris 50 Sette Ou Tao eoe Life-History of the Liver Fluke Peels, Wiss) aulels mals Ankylostoma and Dochmius.. «1 «+ 04 ews New Floscularie .. Five New Floscules, with a Wore on iar. Leidy? ys Gone of Acyclus and JDictyophora. (Plates III. and IV. Figs. 31 and 32.) «2 22 0 : Mode of Application of the aches of the Teach 40 Spermatogenesis in the Nemertinea .. «1 se we Pilidium-Stage of a Nemertine .. 1. ss os Teniade Parasitic in Birds ne Ba ow Mae Dicyemide .. Ho dos GG or Rotifera without Rotatiny Organs Bye on. Nad. She Annelids of the Canary Islands .. «+ 66 66 ws Anatomy and Histology of Terebellides Stroemii as Figogone Gemmipera 2. as 6 2» 0s 00 0 Structure and Development of Picrous Development of Borlasia vivipara «1 we nes New Human Cestode—Ligula Mansoni.. .. Development of Annelids .. 1. 26 02 oo Nervous System of Hirudinea .. Bie of the Leech -. .. <6 Development of Phoronis .. «6 ss we AC Development of Sipunculus nudus ete Sc tate Sternaspis scutata ae A OlnCoehyeh Bod. act Monograph of the Chagas J IC ution ge Owen sc Direct Reproduction of Tenia .. «. Asplanchna Ebbesbornii nov. sp. (Plates Ix. ant x. ) Anatomy and Histology of Polyophthalmus td Be Annelids from That 1. 22 oe Observations on Phreoryctes and Nais.. .. Glands of Morren in the Earthworm .. 1 se os Processes of Division and Regeneration in Earthworms ” Ap Lettie a 2 PAGE 506 507 507 652 654 am 835 836 369 369 371 507 621 655 CONTENTS. Excretory Organs of Hirudinea .. «1 +» 15 ae os Part 5 Nervous System of Solenophorus .. 1 +» 18 we wes Development of Planaria polychroa Development of Annelids 4. +2 se ne ne tw Part 6 Pleurocheta Voseleyi .. .. Seg hve Ar SOS ae Anatomy and Histology of pubis caren Oe), AOOe eer Anatomy of the Hirudinea .. .. . Gok RCO, pUCRmGErEr Spadella marioni .. «6 25 oe ae we newegg UNICORN CIYLELOLCE MN otter nico clown cleo oloMtN kas Wr eles fo a Wale of Oxyuris curvula .. .. Bar ReGlloe MEG. een Female Organs of Ascaris eee Bo eooey boa Coke ep New Worm with Remarkable Nervous System .. .. + Anatomy of Cestoda .. .. Ber toe | ber ar Development of the Ovum of Pitedine, LORIE Aee be Me ocey ay INGO SUISS PELOLQLOT:UC el aay cle) i =le)) ein olo el erol sy Echinodermata. ‘ Challenger’ Holothuroidea.. .. Mio alee Supposed Coral-eating Habits of Echols eit eee eh Othe Stalked Crinoids .. . Bele areata. ye ices aie) ow sieds Th 35 New Deep-Sea Stalked Crinoid Ae OL foo moe. Ihde = tto. meee Asterid from Great Depths .. 4. «5 0 ee ee oe Psolus and its Allies .. .. PRON nisiNian vette kakGtes Perivisceral Fluid of the Sea- Teas BS Chee dune ee ce eer TIUGUGHIOUS) Goo) 2h0S iG fod), 00", co. eG! OG GO ot or Arctic and Antarctic Oat BE cay re eee ae ay sot ae Classification of the Comatule .. . Oa 60 8) ee Spicules of Cucumaria hyndmanni, C. en, and two Allied Forms. (Plate VIII.) Ze] | oat opleacami nest Een Democrinus parfaiti ‘nies Mavis Mut sieeane aisles ome nga Physiology of Dagar sole jada Gael Pewee oouiees eee bee Organization of Echinoderms «1 4» +» ee we ogg ‘Challenger’ Ophiuroids «2 «1 «5 2 ee tt weg New Ophiuroids .. .. SIRO Ora) re Cees Te New Crinoid from the cadens Sea BN Tl ec lar 4 REC torr Histology of Echinodermata OD a he rice gy Bred ete Acanthology of Desmostichous Echinids .. +» ++ oe 9 Ophiurids of the‘ Gazelle? .. 1 6» we we te te Ccelenterata. Nematophores of the Hydroida .. .. ». « « +» Partl Green-cells of Hydra .. .. ae rast vale bss Development of the Ovum of Ber CORTICES ana ys ‘Challenger’ Deep-Sea Meduse .. .. +» +» ee ee os ‘Challenger’ Corals .. . SoM Okereh test seu echoed 09 Morphology of the Coral sictceam ne Cyclical Development and Relationships of the Siphonaphor Part 2 Celenterata of the Southern Seas Being Seats aru al Vaese 7 Observations on Hydre Be cat ene Ser, ons 4 tices ber ery Development of Renilla Bl Reg es he a W's oye teiex an > 99 Scotch Pennatulida .. .. ag ight ssi tars rs ” Origin of the Spermatozoa in diese Ek eee fire fais ato RNG xii PAGE 657 658 658 837 839 840 841 843 843 843 844 845 846 847 847 XiV CONTENTS. Endodermal Nervous System in Hydroids .. Development of the Tentacles of Hydra... Preserving the Fresh-water Medusa. (Fig. 20) Structure of Hydroid Polyps Pecan Os Development of Hydra... Alternation of Generations in Fh Ae ee Hydro-meduse without Digestive Organs Phylogeny of the Siphonophora : Embryonic Tentacular Knobs of certain Pion es Blue Colouring Matter of Rhizostoma.. Symbiosis of Bryozoa and Actinie Celenterates of the Southern Seas Observations on Meduse bef eae oe Reproduction of Hydroid Pana oo 8) New Hydroid Polyp .. « 5 be ar Hard Structures of the Pen Celenterates of the Southern Seas New Meduse from the Red Sea .. Development of Obelia .. American Anthozoa : Hard Structures of the nga Elevated Coral Reefs of Cuba Polymorphism of Alcyonaria .. Ciliated Groove SEE Lea in the Sinedeuge of the Alcyonarians Porifera. Vosmaer’s Porifera .. . 56 eas Fresh-water Sponges of Russia Fungus Parasitic on Sponges .. .. Australian Aplysinide .. ad) os Ovum of Marine Sponges... «- New British Sponge Vital Manifestations of the eons Spermatogenesis in Sycandra Fresh-water Sponges of Bohemia.. Bavarian Fresh-water Sponge African Fresh-water Sponges Protozoa. Suctociliata, a New Group of Infusoria, intermediate between the Ciliata and the Acinetina .. New Infusorian belonging to the Genus Pyne: Systematic Position of Amphidinium .. Evolution of the Peridinina New Thuricola .. Flagellata .. a Microsporidie or Prosi of Ween dasas Bs Development of Gregarine and Coccidia Gregarinide of Annelids .. .. 4. Intestinal Parasites of the Oyster oe PAGE . Part'S 376 a 377 . Part 4 485 39 Oe F 514 3 515 a 516 < 516 > 518 518 Part 5 635 5 663 - 664 p 665 AS 666 666 Part 6 830 x 852 5 853 s 854 3 854 5 854 t 855 855 Part 3 378 * 378 395 Part 4 519 Part 5 667 668 Part 6 856 és 857 a 858 ns 860 aS 860 Part 175 » TY, ” aa » re » 78 ” 79 ” 79 ” 80 9» 81 ” 81 ” 81 Perception of Liyht and Colour by the tien Orerinbhic Pee CONTENTS. XV PAGE Action of Tannin on the Cilia of Infusoria, with remarks on the use of Solution of Sulphurous Oxide in Alcohol. (Chigs 3a) Ont BD) iede mite een eek ised ven) 1 ae alt co BSD IHOREGUES TRUDE, de. oo oO eo 5) ed 221 Observations on Protozoa .. way Giese eee. sate 33 222 New Flagellate—Chlorodesmos isms Be tod ibe, Mica 223 Chologonium euchlorum, Ehrenberg. .. 11 1. 45 - 223 Biitschli’s Protozoa .. op oo Jenne) G7, Flagellate Infusorian, an eermaneere oF mae eeaecln ees 379 Gigantic Actinospherium Eichhornit .. .. .. .. 5 379 Dimorphism of Foraminifera .. . Paci iece Umrao tay ac 380 Vampyrella Helioproteus, a New Tioecear: ote Eee err: 380 ITIL OF SUSU 06 66 oe eo bo ee) ca eg 381 Characters of Infusoria- .. co fo een Ge GAY Development and Classification of ‘Pol vioma, E Tr oe ee te 521 Ophryocystis Bitschlii.. .. . He oe HuRDO BOGE Ee 522 Soci! JEQWOWH: 00 co co eo. cot 523 nving- Or ganisinsitit DIriChiOnke melee) celts a) en sa 5s 923 Eozoon Canadense from Sutherlandshire .. .. .. .. os 615 Covhunntan lata eins pec tseatep aver a a tee ve eee barton OOS RCE RUN GUNMOCCHN cou acc | cloud | tees West (east) reemnNs aee e 668 Nuclei of Protozoa... SO et MEO EES ee 668 Observations on Acdrospiconian ichornt. Teja Vache heres 669 Dimorphism of the Foraminifera.. .. 1. 1. 1. egy 671 New Type of Arenaceous Rhizopoda .. .. .. .» +» 49 672 Fully formed Embryos within a Rhizopod . bs fc 672 Detection of Polycystina within the Mermeticay Ose Cavities of Nodular Flimts .. 4. se 0s «0 «0 4 673 Endoparasitic Protista Hump e eee oe woe. Gude Ok tee 673 Studies on the Gregarinida .. .. 1. 4. 00 ee we gg 675 Chlorophyll in Vorticelle .. <. .» « «=» « « Part6 860 Action of Tannin on Infusoria .. .. «2 11 11 ey 861 NG US WISS Lief USOTIG eet eas 5 Pea rek, cere Staten ee 35 861 New Peritrichous Infusoria sie, PUcinn, Moon pucebe Us aienn teen Meee 861 Abyssal Tupavoy Orbitontes\-.. 2.0) so. oo sole sey) aa oa 862 Trypanosoma balbiant .. : 862 Chrysopysxis bipes Stein anon Seriulavia ihren) +5 863 BOTANY. A.—GeEnz=RAL, including Embryology and Histology of the Phanerogamia. Development of the Pollen of Orchidee .. .. .. .. Part1 84 Formation of the Pollen-grains in Gymnosperms .. .. 4, 84 Conduction of Pollen-tubes .. 2. 61 su ne ewe gy 86 Female Flowers of Conifere ae BopGos meee ieee 86 Flower adapted for Fertilization by Saatien oC GIS ce 87 Insects and the Cross-fertilization of lelaers co yates an Ph ep 87 Development of the Wing of the Seed of Rhinanthus.. .. ,, 87 Nature of the Growing Point ..) 6. 1. cw wes Apical Growth in Gymnosperms .. .. «2 ee newegg 88 Cell-Nucleus.. .. AG ici ee 88 Structure nie Feenation of the Cell- iia Bate Xvi CONTENTS. PAGE Superficial Growth of the Cell-wall .. . «.. « « Partl 90 Mechanism of the Structure of the Cell-wall 1. .. «2 yy 90 Function of Lime in Germination a6 Tei) 9 fafa) gis nS 90 Structure and Function of Epidermal Tissue An 91 Influence of different conditions on the Epidermis of ee 5D 91 Influence of Light on the Assimilating Tissue of Leaves Development and Structure of Sieve-Tubes.. 1. «2 «» 4 92 Anatomy of Bark.. .. SG Poe. tp 93 Absorption through the Epider mis : of Beri Braane SG. a 93 Protein-Crystalloids of the Potato .. .. « «1 «+ gy 94 Hypochlorin .. an AOL dae A 5 94 Crystals of Chlor pony Sooo, oe acess xp 94 (Ofeyytoillonre's Op COTRESOAB oy 50 00 95 Non-calcareous Cystoliths 5s 95 Sete Chel (MARE 55 bo 0 96 Phenological Inversions .. . co> Gee’ p) coke mS 96 Protection of Plants from the Toute Fungs gi ‘eG 97 Detmer's Vegetable Physiology: \s. fas ace se) fee) es 98 Living and Dead Protoplasm .. ac Part 2 225 Continuity of Protoplasm in the Motile ‘Or ae of Dena £ 225 Development of the Embryo of Ruppia and ETAT i ae 226 Plurality of Cotyledonsin Persoonia .. 2. 2» ss ss 4p 226 Division of the Nucleus and of the Cell .. 1 «ss 0» 55 227 Nucleus of the Cells of Secreting Tissue .. .. « +» 35 230 Analysis of Vegetable Tissues .. . G0 da adh 232 Chemical Composition of Vegetable Ticcueas, fae So fom: “Ap 232 Structure of Leaves in Relation to Nyctitropism tas 235 Transparent Dots in Leaves BG le cee LAO op 236 Epinasty of Leaves .. . SP md oop oh co. |p 237 Starch-generators and ant toe He COP CON Oe 5 238 Honey-glands of Crucifere .. .. «. TH ode 3 239 Organs intermediate between Root and Rae Pern Phe?) 55 239 Sieve-tubes .. .. Fee Agrercg! co 240 Adventitious Roots of teas ieilotis. sit) Hiioiey SoiS's ay Ee 241 Generation of Heat by Arum italicum SO ag OA eS 242 Hormicand Acetic Acids in Plants. 9... s< 0s 0 a» ~ 3p 243 Fertilization of Flowers by Insects... 9 243 Influence of the Electric Light on the Develnpment us bakes ns 243 Nature of the Process of Fertilization Aree ode Ag etic) Grell TOUR LBONIO) MAS ACEC ae) tive nl Viele Diels Mee Iiteol ley ies pis 382 Pollen-tubes .. .. ie Wit o) feck, SOeaenES 382 Autoxidation in Tirta Vegetable Cells aah Rieder twnas es 382 Structure of the Bundle-sheath .. 1. .0 see 5: 383 Buried Leaf-buds.. .. ate pes. Whee we tats *r 384 Structure of the Wood of Conifers TS Ca Shee tree 384 Medullary Rays of Conifers and Dicotyledons .. .. &p 384 Diagnostic Value of the Number and Height of the Reacts lary Rays in Conifers... Ay Beced pero bed ae ay" 385 Achenial Hairs and Fibres of Criouite eG.) pres soe ns 385 Crystals of Calcium oxalate in the Cell-wall .. «s 55 385 Influence of Sunny and Shaded Localities on the Dison: ment of Leaves Tees: We wee ceek ps5 et oml soul bse 9) ses 385 CONTENTS. XVil PAGE Position. of Leaves in respect to nue oo ono RR) Gi Photepinasty of Leaves Mab aelaiee car ie pata ihc a coca ou ainr a nares 386 Movements of Leaves and Fruits.. 1. «. 50. 6p 386 Distribution of Water in the Heliotropic Parts 7 Plants Bots iB 387 Excretion of Water from Leaves 60 00 a0. 60) = “Ee 387 Movements of Water in Plants .. «1 «2 + 26 «2 4 387 Permeability of Wood to Water .. +. # A OOh eae 389 Trichomatic Origin and Formation of some Cystoliths 0 oD 889 Formation of Starch out of Sugar .. 1. +» oe wey 389 Distribution of Energy in the Conon ieseceae 00 90 390 Colour and Assimilation 1. s« «© o6 «» «2 « 4 v0 Occurrence of Allantoin and Asparagin in Young Leaves.. ;, 391 Cholesterin, Phytosterin, Paracholesterin, fc. 1. +» «» 391 Respiration of Submerged Parts of Plants.. .. «2 «+ 4 391 Freezing of Liquids in Living Vegetable Tissue.. 1» « 4 391 Influence of Electricity on Vegetation Be Oh ORD 392 Continuity of Protoplasm through the Walls of Cells ro po lsthanc. ay-t- Pollination of Rulingia.. .. 00. 00 gf 525 Development of Gil wonlbarties baa Pee ears ARE es 25 Effect of Tension of the Bark on the Formation of the Annual Rings of Wood, and on the Lrection of the Medullary Raysi «wis wksesaa Sant eeeers Vceraee hese ois 527 Formation and Properties of Duramen 11 oo 06 «2 49 527 HS aie of Vegetable and Artificial Colloid- COUS oa a Vor IR Oe aC ance lteel aL BAN LOGY NOG ey EH 528 Origin of “ Cell- Teens OCR MET plat O i tee OO ere EZ Collenchyma .. +» as HOM DOEAO. sion een cane ep 529 Structure of the Pericarp of Orchitee 5 69 06 0p 530 Chemistnylof Woody) Lissuies se. sa =) es) ee) os 5s 530 Hirst Productspf Assimilation .. ss s. «« «6 «9 959 530 Selective Power of Absorption of Roots 1. .. « + 45 530 Movements of Water in Plants .. .. 6 6 «8 SD 531 Movements of Water in the Vessels .. .. .. «2 « gy 531 Euxudation of Water from Leaves ., .. «2 «6 « 9 531 Jal OPGOHUHD, UR 0G IROWHD co 532 Function of Tannin in Metastasis Ps de 60 gp 532 Laws which regulate the Production of Male and noe Y HODGES nS. ere, Moca tho hamaos roo" Sapo Neo ae dod. tee 532 Selenotropism of Plants .. . aoitapint Timor PapDa Sh 534 Withering of Flowers and Leafy ‘Shoots 86108 100) Ba sig 534 THOR PAG GOP AUTOS Gs po.) db. 00. 00" bo 0D. ac x 535 Influence of Mineral Substances on Germination .. .. 5 535 Occurrence of Zron in Plants AG eo ialtios PED caem ad a 536 Morphology of the Embryo .. 1. +» ae oe Swe Sw Patt 5 675 Ceilulin, « modification of Cellulose... .« Co Aes ate 676 Eavemsinp of the Endosperm through the Micropyle 60° oc. “Ef 677 Development of the Pollen of Juncacee and Cyperacee Fe 677 Continuity of Protoplasm through Walls of Vegetable Cells cf 677 Pores in the Outer Walls of Epidermal Cells 1. + « 3 678 Physiology of the Undulations of the Lateral Walls of the Eipidermis.. .. os ; aa Rieter ays “e 678 Structure and Function of the Apiiormal Tissue Fibra ee 679 Ser. 2—Vou. TIL. b XVill CONTENTS. Protective Sheath and its Be a gs . Part 5 Haptera fe ae a ee ware x Chlorophyll and Chior igi 5 Chlorophyll and the Distribution of ner “gy in Vi ‘Salar Spectrum .. ne 4 Crystalline Secondary Remuaahs of Ohlor "bh me PA Crystalloids in the Pyrolacee ; Ri woop Inulin in the Artichoke Ai Ue Se oe CORTE ERAS. 30 Mentzelia levicaulis as a Fly-catcher .. os Fertilization of the Borraginacee 56 Part 6 Pollinationvof (Cypeulayen ser. se) is ee i os |e sy ‘Pollination of Rutace@.. ss« ss 2» 0 ss eo se 3 Division of the Nucleus BS y ke ores! oy kore .or BS Albumen, Nuclein, and Plastin 5 Chemical Changes in the Germination of Bar aa a) Function of Amygdalin in Germination es Galvanic Phenomena in Germinating Seeds 2 re Mechanical Protection of Seeds against External Injury . a Lignification of Epidermal Membranes soon ” Protective Sheath and its SRS a Laticiferous Tubes a Medullary Vascular aes of § some Diootytoton a Wutating Internodes .. +. 2 « ad) on 3 Function of the Apex of Reus a0 00 A Transpiration and Ae. Zf Wailer o Bvaishin 4 in Winter —.. ac de = fk A ode od or Hydrotropism + Influence of canines Atmospheric Pavin eon oe Gronks of Plants... 5 Effect of Eada Beat on the Groin oP Plante a Colouring Matter of Flowers... «. Bo VOD ” Botanical Micro-Chemistry .. «+ +s as B.—CryPToGAmMIA. Paleontological Development of Cryptogams .. . Part 4 Organic Unicellular Bodies in Coal p op Rabenhorst’s Cryptogamic Flora of Germany, So. A lets Cryptogamia Vascularia. Chetopteridee .. . Dees Tube rise teh eee Development of the ae of Bae FAg Oo Pole yoce - op Peculiar Form of Stereome in Ferns .. ; . Part 2 Structure and Branching of Dorsiventral Pioodincas a Worth American Tsoctes 2. 01 06 08 »6 8 #0 99 Male Prothallium of Equisetum .. .. .. . «o « Part3 Reproductive Organs of Pilularia ie, WAL greta = tAcrighebrancnesiof Psion ss. fos ce se we egy Underground Branches of Psilotum .. .. BS So Sonu tas Fibrovascular Bundles of Vascular Cfetogainks .. Part 4 Cryptogramme and Pellea .. .. Si Lodhi es eee Part 6 Vascular Bundles of the Leaf of Sphenopyltm “eh ob Structure of Phylloglossum .. .. apa PAGE 679 680 680 682 682 683 683 683 864 864 864 864 866 866 866 867 867 875 CONTENTS. Muscineze. Structure and Classification of Muscinee .. .. .. «. Partl Male Inflorescence of Muscinee .. «1 «. « « «. Part3 Antheridium of Hepatice Bg ca Meee leis, er eres Anatomical Structure of Mosses .. .. .. .. « .. Part4 Hybrid Moss... oF Physiological Function a the Cont -al Burgin ¢ mm oie Stem Oj? JUGSSIEB oo co od G0. 0 Dos ET (E Characez. Monograph of Charace «=o» oe we Swe Swe Sl Part 3 Fungi. Minute Form of Parasitical Protophyte .. .. .. .. Partl Protection of Plants from the Lower Fungi AO. BOn' Seco = ane Abnormal Hymenomycetes 5. .. «+ «1 «2 se oF 45 JEUSUUORCENE MGC Go or oe oe Se ING@D AISCORCRIES o¢ on GO ee og ING AHP oo 00 SG | Go. pO. Ro) Mob © co do rp Coremium of Venecaiunes seit oils Ce nictt were Lib wieht Vcltates sin oat Exoascus .. . sisal soiothics ccrostiid) 'ojeHlve's/sAb craic L tale tttarey) ok ras Sporendonema casei > Das hie PCET Ueno el Serer eine are va Entomophthoree .. .. 5 Influence of Acids on lesen one on ‘the Darden of Torula.. .. oc OR gp Influence of Alcohol on ihe Deucionent of Torula 5 New Species of Mortierella (Mucorini) s Development of Mould-Fungi in the Bodies of Men one He Animals : Pe aeoO mavc. GES)” a Physiological £; ‘fects of t various Fermants Bet asian erg ce Carriage of Schizomycetes through the Air.. .. .. + Transition between Forms of Schizomycetes ch ot op Fatty Bodies as Generators of Bacteria i Phosphorescence caused by Bacteria : 2 Inoculation of Tuberculosis through Raphetn. Parasitic Myxomycetes - cc Spermogonia of Uredinee and their Belatiand to eee -. Part 2 Reproductive Organs of Ascomycetes .. .. : Fecundation of Achlya and Saprolegnia Morphology and Development of the Poriucun “ Meliola Selenosporium aqueductum .. A Hypholoma fasciculare, an enemy to Feces Paipalopsis Irmischie . Pathogenous Mould-Fungi BOD p De anD. ener Organisms in the Mould of Beer... .. 1. 22 as oe Schizomycetes and Schizophycee .. .. 2. ses Microphytes of Caries of the Teeth .. Bacilli in Condensed cee oe ae the BE of of Phthisical Persons .. . oe oo ‘BGGHIUS GUUCGUIOSES “Warm alco? (ratte “ais dt) oakt (Zak bees Bacteria of the Air and Soil Be Pee SR eS oe Bacterium photometricum .. b2 XIX PAGE 100 395 3995 038 538 876 396 26 97 101 101 102 102 102 102 102 103 103 104 104 104 105 106 106 106 106 106 107 246 247 247 248 249 249 249 250 252 253 254 255 255 255 256 B.9:¢ CONTENTS. PAGE Crystallizable Substance produced by a Bacterium . Part 2 258 Germinating Spores of Agaricus (Mycena) evipteragi Scop. ties sce so sobs § oc 318 Red Mould of Barley. ( Plates Y. Oe VI. )) Paecmemes . Bart 3 321 Cultivation and Life-History of the Ringworm Fangs (Trichophyton tonsurans). a VIL) 5 ss 329 Physiology of Fungi ss «+8 ow 59. o8 = 396 Fungus Parasitic on Sponges +2 +e an te ewe 396 Glycogen in the Mucorini 11 se oe oe ewe * 397 Hetercecism of the Uredines.. 11 1. 0+ ewe 5 398 Infectivity of the Blood 41 uu ve nets ” 399 New Species of Micrococcus... qo ae as 399 Influence of Light on the Deer of paaene x ” 399 Bacteria connected genetically with an Alga “6 400 Bacterial investigation of Sunlight, eee and the ale a Edison's Lamp... .« o« « Nees . “ 401 Microbia of Marine Fish «2. ws Peto © op 402 Movements of Minute Particles in Air and Waiter S/o iret NS 402 Miquel’s ‘ Living Organisms of the Atmosphere’ be) crow eS 403 Observations on three Human Contagia 41 ss weg 479 Localization of the Hymenium of Fungi. +e ws Part 4 538 Chemistry of “ Fairy-Rings” 4. ue oe we eg 539 Fungus Parasites of the Awrantiacee .. 42 « « «8 4 539 OCCU Moe) bet aie ele | ioe fees’) ps * 539 LOPPERESSG) Wee toe) Ustog oiap) delet, Get sleiet Wisin Wwe aioe) | Ways 540 Lophiostoma cespitosum 1 ae sew rH 540 Oidium albicans .. «s 2° BE eo ip 540 Investigation and Culture of Panhigewnss Babion 1B ine foes AN 541 Earthworms in Propagation of Charbon .. «6 «+ « 49 541 Transmission of Bacteria from the Soil into the Air .. x 541 Fresh Method of Vaccination for Symptomatic Anthrax .. 4, 542 Organic Particles in the Air of Mountains.. .. . «+ 4 542 New Myxomycete.. 1 oF aces boty ete was 543 Abstriction and Separation of the cee of Fiingi 7s oe Pattionoce Fungus parasitic on a mature Coleopter +. +. + 685 New or little-known Parasitic Fumgi .. «6 +6 +e oe 15 685 Exoascus of the Cherry PA uae ace ecce RCO Secor a 686 Hyacinth-diseases.. 6. 06 06 0 08 08 oF 8 3 686 Identity of Oidium monosporium West, Peronospora obliqua Cooke, and Ramularia obovata Fl... +2 oe +e egy 686 New Form of Potato Disease.» ss « of oF oF 9 687 Spermamebee of the Saprolegnice OM SP Grom Ao Se 687 Schizomycetes .» « ov o «oF ef 8 08 « 49 688 Action of Heat on Pathogenous Bacteria .. « « « 690 Fermentation of Bread Cee eg acc pescemecn, | ek 690 PRORMEE wcS ee i cs os) on Ge lee “ies Ge ee REO ee Brefeld’s Ustilaginew .. 11 +s se ee re te eo 877 New Ustilaginee .. 66 06 6 6 ve oe oe egg 878 Development of Ascomycetes .. oe to oh 878 Aspergillus and Eurotium, and their Relation to Otomycoats + 879 New Parasitic Fungi .. 01 oF oF 08 oF 0 oF 99 880 Chesinut Disease .» 0. ov 08 8 wh 08 00 es 880 OONTENTS. xxl PAGE GHEIGTES on 0G 00 Goo 600 oo dB SD) Zygospores of Mucorini. as 0G, 41G0) "to! 60-9) 881 New Schizomycete (Leptothria gigantea) ele Pesta ciety) ys 882 Bacterium LOPE cp sid ad at | dels eh se se) ae 9 882 Diastatic Ferment of Bacteria ov ss 1 «6 «i 06 49 883 WU erOUMROf Lisl aay cae ds Maxell Me eaeD tel Bam ee oes ey 287 Correction-adjustment for ae ye obo SG ABs. ae 288 Podura Scale oc sem erena uctehatatee wectee = a 290 Resolving Amphipleura pallutide.: - 230 Correction-collar to Zeiss’s Boerne arenes Objectives ~ 314 Heliotype Photo-micrographs of Mosses, &c. a eects 318 New Form of Abbe Condenser .. 319 Portable Form of Aéroscope and Leper. (Figs. 58 ror 59) Part 3 338 Bertrand’s Petrological Microscope. (Figs. 60-62) .. = 413 Fase’s Portable Binocular Dissecting and Mounting Micro- SCOpea | CHtgaiGS) in ec ee Rat ach 415 Klinne and Miiller’s and Seibert’s letersi Mie scopes. (Figs. 64 and 65) .. EN CE A hb. cr 417 Seibert’s Travelling Microscope. (Fig. 66). ne 418 Klénne and Miiller’s “* Pendulum Stage.” (Figs. 67 and 68) x 418 Leiter and Mikulicz’s Gastroscopes. (Figs. 69 and be AA 421 Cobweb Micrometers .. .. ne ; 422 Chevalier’s Camera Lucida. (Fig. 71) ea coasts Talkie amuane ce 423 Grunow’s Camera Lucida. (Fig. 72) ee Penewety: 423 Holle’s Drawing Apparatus.. .. Bey ibe ete 423 Manipulation of the Beck Vertical iiieinetor ae as 424 Pease’s “ Facility” Nose-piece. (Fig. 73).. Be wGOu apr 425 German “ Cylinder ee ” and Condensers. (Figs. Tell) eee cc a 426 Pinkernelle’s epee fe the (Reeensiannione of Fluids. (Pigs (Ses Fe okt os he ae poe Bee heen epee well Lez) Moist Time pape Ox Ff 428 Hartnack and Prasmionnets 4s Paleresing Pris (Figs. 79-82) cf 428 Apparatus for Rotating ee ae oe (Figs. 83 and SE) Be. ee Cte ici Bi ee cee occ 434 Abbe’s Guerin Seon (Fig. 85). eae x 435 Hartnack's Illuminating Apparatus for aieeaachiatraata Light. (Fig. 86) - 436 ee of Variable cee Magnification bv the Micro- scope . ss 437 XXIV CONTENTS. PAGE EARP Op IONICS “ra aa co 60 cu ou do Levande) 23) Home-made Substage Condenser .. .. 6 6 «2 «8 149 440 Work-table .. ovale aide eat? Spe Se meee 440 Testing Microscope Objectives ine feb Coe con Enel oG 441 Lamp-shade.. .. “ ames iene) es ms 441 Bausch and Lomb’s Optical Co? s eno etsian .. » Part 4 548 Fase’s Portable Dissecting Microscope. a, gs. 91 and a 6 550 Holman Lantern Microscope. (Fig. 93) . SD feta tips Pa 551 Nelson’s Student’s Microscope. (Fig. 94).. .. . « 459 554 Watson’s Portable Swinging Mirror and Substage Micro- SCONE Sm CHAGeLOO)) me elaer> 5G. ate Gon PtaGk Sp 554 Walmsley’s Photographic A Sparatie (Fig. WO oo 60° ° 556 Hauer’s Photographic Apparatus. (Fig. 97) .. 11 «6 yy 559 Seibert and Krafft’s Small Camera Lucida. (Fig. 98) 0 560 Winkel’s Small Camera Lucida. (Fig. 99) alas 5 560 Correction of the Distortions produced ‘ the Games Incida. (Figs. 100-102) ; 5 560 Measurement of Microscopical Marans Wea) OP 108) 567 Simple and Cheap Eye-piece Micrometer .. 53 OOD 570 Nelson’s New Nose-piece Adapter. (Fig. 104).. =) 572 Curties’ Nose-piece Adapter. (Fig.105).. .. " 572 Zeiss’s Stage-Micrometer. (Fig. 106) ay 573 Queen’s Holder for Woodward’s Prism. (Fig. 107). BOM cfs 573 Lineyaonpyanls COME BEP ago 00 co 574 UU LONNOUMSUNIGHE aivete) saison iels! NN fetel cio) ree ois ss 574 Blue-tinted Lamp-chimneys, Light-moderators, fc. .. ++ 5 579 Thompson's Polarizing Prism. (Figs. 108-112) sir Sage 575 oe of Vision in Photomicrography Moy deste 5 cine Ete ane 579 Talue of Photography in Microscopical Banatiy atone) SO eer 580 ass Refractometer. (Figs. 113-116) .. .. Cree; 581 Refractive Indices and Dispersive Powers of Solids and Fluids ae eae one ode eS) MeO Soo yy et 587 “ The Genus eee Re ae ce i one ee, Mon 4! Xp 589 SAU TUOMAS ACUMEN RLCING) Nerel Weis teen Witciots © se) lesan ael iss 593 Possible Error in Micropetrographic Dien aaeais Sem de kaetes 594 Amphipleura pellucida by Central Light .. 1. ws «oy 595 oroTISEO NM ONS ue | Meleuia Bove Mrelon, Wsaphe fae) (ele) Meio ace» pe 595 Rogers’ Standard Risin: SO Obes CO Oh EC. ache oy 619 Bailey’s Portable Microscope. (Figs. 120 and 121).. .. Part 5 697 Chevallier’s Inclininy Microscope (large model). (Figs. TVRETPADY. “ree So dog CO ORs Meee meu WemM ce GeicreL we 698 Chevalier’s Microscopes. (Fig.125).. .. . o 700 Hirschwald’s Microscope-Goniometer. (Figs. 126 a 127) 9 700 Pliss?’'s Large Stand. (Fig. 128) .. .. we a 703 Suift and Son’s Radial iia anaes gs 129 “pel TED) sy) 5a eee Ac ay Meo, ae. 8 704 Projecting Pane he rely ate 9 706 Assyrian Lens. (Figs. 131 po: 132).. SRR OD Varina Neth 707 Lindsay’s Microscope. (Pigs. 183 and 134) .. «. 3 708 Janssen’s Microscope, (Fig.185) .. .. .. « dp 708 CONTENTS. KKV PAGE “ Contribution to the History of the Be wre (igs: V6 and W371)... oan eat OmOe. Staniilepa! IBNGJUGGES on ce ct ct 711 Chips Glnugra IGuemle be pb oa) ee ee oa 460.) ee 713 Standard Body-tube for Microscopes .. .. «1 of « 4 713 Sliding Body-tubes 50 od Sy eeeaurcitih Oulton elie tare)! in ias 713 ACs S INOSEFIEEE? co 00 00 ce oc 713: Smith's Rotating Stage oc ae near 713 Bausch and Lomb Optical Co.’s Compress ties: 138 cmp) BE) Be oo doi" Ge At GobiRe bats Coma wch 714 Frog-plate. Gian 140) Fa, 2b Ss 715 Apparatus for Examining the Gentine & m ae ae we WMesentery of the Frog. (Figs. 141-147)... . 5 715 Madan’s Modification of Darker’s Selenite Holder. gs 148-150)... .. .. ae thee 718 Sternberg’s ‘ Photomicrogr “es ome hone to walie en mts 720 Photomicrography, by Lamplight .. .. .. ss se «+ 45 72k Focusing the Image in Photomicrography .. .. «=» ««. » 122 Aperture-shutter A sale tee Vas ntese “ 724 Central and Oblique Light for Beclation SPURAE Cap SC Hs EoTe —ieE 724 TeCrshHGS SHiOGS oo cc 0G oe 00g 724 Rogers’ Microscopic Scissors eye CEN EBD me Oe + ttn ho op 725 Llectric Light applied to the Bema oh evvaed oe (een imren iiss 125 Substitute for a Revolving Table.. .. -. « «se «+ 49 725: EEROGIUG AUGER. 95 99 00 tu tC (gh 726 Watson’s Shudent’s Microscope .. .. POMS Boge Ale 726 Relation of Aperture and Power in the Meuroscene ye) ee arto, 790 Schréder’s New Camera Lucida, (Figs. 152and153) .. 4, 813: se Opiicalelube= (crea tit a Cigale 4) sei iiteit nl -[ae eles 816 Beck’s Pathological Microscope. oe LOT) Mesa teres ite edeihiatss 894 Chevalier’s Microscopes ai alie Vosattenk greta oR AN oro Ea ont Ms 896 Swift & Son’s Pocket ieeecepes (figs. 158 and 159) .. 896. Mirands Revolver Microscope. (Fig. 160) .. «. «.. 4 897 Pelletan’s “* Continental” Microscope. (Fig. 161) .. .. 5 899 Zeiss’s Mineralogical Microscope. (Fig. 162) .. .. .. 3 900: Bausch and Lomb Optical Company’s Fitting for 2 Neutral Tint Camera Lucida. (Fig-163).. .. «. - 902. Testing the Binocular Arrangement .. ee 902. Bausch and Lomb Optical Company’s Safety Nose pic. Gig IG. bet sa det eda ees » 903: Matthews’ Device for Exchanging Objectives. (Fig. 165) 903. Watson’s Adapter Nose-piece. (Fig. 166) BaMuh iste patel Cee 9 904 Boecker’s Movable Stage. €Fig. 167)... .- « «= -» » 9O0t Polis Compressors (ig. (GS) wae) Yee tea) ae ioe) A) sy 905. Slack’s Tubular Live-box. (Fig. 169) iis oo, 00... gE 906 Wenham’s Reflex Elluminator .. .. « se « «» 4 907 Practical Benefits conferred by the Microscope... .. .«. 907 Bale’s Simple Eye-piece Micrometer .. .. « «+ «« y 908 Microphotographs of Transplanted Teeth .. «1 «+» «+ 49 909 Divisions of Micrometer Eye-piece 1. as ee we gy 902 ~y a7 XXV1 CONTENTS. PAGE Substitute for a Reading-table .. .. So se ae) Parole Spencer’s 1-10th Homogeneous Immersion Objective ay dase aS 911 American Society of Microscopists anes 3 935 g. Collecting, Mounting and Examining Objects, &c. Carbonic Acid as a Narcotic for Marine Animals .. .. Part 1 137 Corallin as a Microscopical Reagent .. oy ee Preparing Bacillus tuberculosis Sa) doa AO Oe =p 139 Staming Bacteria. (5. 5 a» 6s ¢s +5 «> = 5 139 Preparing Fatty Acids.. 3 141 Carmine Solution .. 55 141 Prussian Blue and Safronine for Plant Bectioe 5 er 142 Injection-Masses .... 5G tops, oe 142 Taylor’s Freezing hercioms. (Fg. 20) ae etn, Mecte ay 143 Mounting Media . Se Saito oo. 9 ch 144 Preparation of Dammar vor can ae) ed alee eee e ice Mans 145 Hunt’s American Cement os 145 * Mayer's Water Bath. (Fig. 30) ea 145 Packing Slides for Travelling .. «e+e ne we weg 146 Examination of Living Germs in Water ns. ucts Sees 146 Sinel’s Embryological Slides Hie Sas Scauneos . Gacusy 147 Search for “ Atlantis” with the Micr sce. . 148 Cole’s Studies in Microscopical Science ec sie s Get Bie 149 Cutting Sections of Dental Pulp.. .. «. St aes 150 Examination and Exhibition of Living Drains Bp 150 Mounting Plants in Glycerine and Water... «1 +e 155 J51 Preventing grovth of Mildew on Dry Mounts 33 151 Bleaching Fluid for Insects.. .. «2 «2 «1 «8 0 33 151 How to Preserve Urinary Deposits .. .. «+e «+e «8 499 152 Mounting in Glycerine . x 152 Action of Tannin on the Cilia of inflame with Ge on the use of Solution of so pandid Oxide in Alcohol. (Bigs. 33: and 34)... tes as se we oe MER Collecting Small Organisms... .. nee ee 290 Chloride of Gold and Cadmium for Rar minaian + 290 Monobromide of Naphthaline for Histological Preparations ss 291 Sulphocyanides of Ammonium and Potassium as Histological Reagents .. = 291 Preserving Insects, Oratiiea, vase, SF nati Tavertsirates * 292 Mounting the Proboscis of a Fly.. «1 + B; 292 Preserving and Staining Protozoa ep teet dese te Preservative for Fungi.. .. « She baie cy" 294 Osmic Acid for ss drcasinar Seca " 295 Carbolic Acid in Mounting . ot Voie eo ce, BINSeh + pe emmane 296 Injection Methods 29 ees eli Aen ele 297 Ceresine and Vaseline for Tete foe oS 298 Paul’s Modification of Williams’ Frescing Micotantts Bi as 298 Thoma’s Sliding Microtome eee nee baie: DLO) wal) Keil fee Ls 2: 3 298 Fixing Sections 4.0 20 on ps os ne pe eke 307 CONTENTS. XXVll PAGE Mounting Sceions ny SenicSxe ase 2+ ee 2s) ee HOTt 2 30S Creesé’s Turntable. (Fig.57) .. .. 5 308 Simple Method of Mounting Objects an eee Examination .. . hte sey Bl ane = 309 Hudson's Extract of Soap for Cleaning Slides seeriteemess sh 310 Preparations of Mineral Crystals Bs a CC A em Dee 55 312 Tapacr aly jptir JUOUTIGTEG on on eg 312 Removing Air from Diatoms .. Bes agit ix eg OCT nere 312 Preparing and Cutting Amphibian Bags Ba ics ree oige Wearim44 2, Preparing Sections of and Examining Embryos.. .. .. 4 443 Imbedding Small Bodies .. .. BOP soc See re 444 Mounting Insects in Balsam without Presse Bue bine ae as 444 Reagent for Simultaneous Staining and Hardening .. . a 445 Anilin Colouring Matters as Staining Media for aie and Animal Tissues... .. of 446 Double Staining Nucleated Bie atenanatacles with ‘Anilin DYES a0 0c re 447 Deecke’s Mi CHO Gitlin ae Monting Sections thr Wa the Entire Human Brain. ee 5G Ege ue Ie re 449 Schulze’s Section-stretcher. (Fig. 87). iad WO miaha, «letra wale 450 legyerorin Of Alene IMG oe eb ek be eg 451 AT ORG OUGUE Of IDTMGRE 5 05 os 00 ce tg 452 I OMCTH OCLISS Raa) mse me igies Newser ciom Nn cleh ecreak a istech Ie sepa el a 453 Atatineg Ranyoon GHB 25 te ce 5) eg 454 Ivory Drop-Black Pears Omron pen cou Or. ort) Sore. er 455 Selection of Cover-glass Penemers Wlooe tens ase Ty Woe corey 455 Labelling Slides .. .. sige kteteleel Soren dress es eee 456 Economical Cabinet for Slides ain: ek ele Ould aves aehecyond, Mtore lanes uamaatia 456 Moller’s Typen- ond Probe-Platten .. 2. .. . «» gy 457 Slack’s Silica Films .. . Wet de ee Swiss Hydrachnide Ay eee CM ame YT ee Mee ck Firmdlahice of the Orustacean Limb. 1. 5. 2. daa taay ena ee Characters of Nebalia.. — .. a {depos toa hea ec BIS yk aa ee en ta System yf Palemonetes variane.. 1... gi sedhere (sain ghia aa w Genus and Species of Lyncodaphnidzs PE EAREre er See AT ty neater ee righ of Sabellid z& e oe oo oe « oo «e oe oe on «e «a 58 ae C35 Summary or Current Resparones, &c.—continued. Norith-Sea Anireltds se = aes ow we = 0 PAG TT Es ce a ee Ce a seen ee ey Sick ar EO Ctenodrilus pardalis .. .. «. Distichopus ~.. “8 Turriform Constructions by Earth-worms .. Hamingia arctica ERR AE ee Pe OMe G Anatomy of Prorhynchus asics Ek: Monograph on the Turbellarians HiRes eater es Dinophilus apatris .. darian Life-history of the Liver Fluke tins rene nha Ankylostoma and Dochmnius bee eaeraian ean New Flosculariz.. .. SL ein bay a aiken ‘ Challenger’? Holeituroiden: <8 228 a Nematophores of the Hydrotda .. .. as ae Green-cells of Hydra .. .. ee Development of the Ovum of Podocoryne cc car ned ‘Challenger’ Deep-Sea Medusz aaron ‘Challenger’ Corals .. Sea Morphology of the Coral- Skeleton Suctociliata, a New Group of Infusoria, inter mediate ‘between the Ciliata and the Acinetina . New Infusorian belonging to the Genus Pyicol Systematic Position of ep ladinnin Spee Heolution of the Peridinina .. PI Rene New Thuricola .. per e es sca Flagellata 3 Microsporidiz or Psorospermize ‘of Anticulates ce Development of Gregarinz and Coccidia.. Ba Gregarinide of Annelids Bs Intestinal Parasites of the Oyster | Perception of Light and Colour by the lowest Organisms Botany, Development of the Pollen of Orchidew 4... Formation of the Pollen-grains in Gy Clie ate Conduction of Pollen-tubes ; Nera Female Flowers of Conifere .. Flower adapted for Fertilization by ‘Snails Insects and the Cross-fertilization of Flowers Development of the Wing of the Seed of . Fehinandin A Nature of the Growing Point .. .. oo Apical Growth in Gymnosperms Peri Cell-Nucleus .. ~ Structure and: Formation of the ‘Cell-Nucleus if Superficial Growth of the Cell-wall-.. .. .. Mechanism of the Structure of the Cell-wall .. Function of Lime in Germination 4 Structure and. Function of Epidermal Tissue. Influence of different conditions on the Tipidermis of Leaves Influence of Light on the Assimilating Tissue of Leaves Development and Structure of Sieve-Tubes .. * Anatomy of Bark A Absorption through the Epidermis of Aeréal Organs. _. Protein-Crystalloids of the Potato Re Sey his aaa eetae ~ Hypocklorin.. —.. Seg rtenintiwe ctaee yee apa Crystals of Chlorophyll. we tga obi) Weert tae Crystalloids of Cupressine® 2. tee te Non-ca lareous Cystolithe .. 9 140 - . ee ae “Tannin and Aleurone: 2. én oe Lice. ee a ne Phznological. Inversions. .. mangas Protection of Plants from the Love F ung nea Detmer’s Vegetable Physiology .. .. Chetopteridex .. ss hale Development of the Spores of Scdoinin. Rie and eeueie and, ase see of Museinex << Gf} Summary or Current Reszarcues, &¢.—continued, Abnormal Hymenomycetes .. 0 +e ee ee ee bee a nae Phosphorescent Agaric New Ascomycetes .. New Entyloma .. +s ee Coreineans of Verticillium .. Hxoascus aes Backer Sporendonema Saeed Diemar 22. ye Entomophthorex .. : ‘Say Influence of Acids on Fermentation and on n the "Development of Torula Influence of Alcohol on the Development of Torula ay New Species of Mortierella (Mucorini) .. Si Development of Mould-Fungt in the Bodies of Men and other Animals Physiological Effects of various Ferments es Carriage of Schizomycetes through the Air Transition between forms of Schizomycetes Fatty Bodies as Generators of Bacteria .. Phosphorescence caused by Bacteria : Inoculation of Tuberculosis through Respiration Parasitic Myxomycetes _.. Sart Marchesettia, a New Genus of Floridex es Pie SAAS Sie fame Chromophyton BOR ROMT Siok Say pee dS obo eee ee ae Phyllosiphon Arisarit .. «+ Say eax Argentine and Patagonian Algee SS Swedish Pediastrex, Protococcacex, and Palmellacex Re Crenothrix Kihniana as a Contaminator of Water Alga parasitic on a Snake . ete en Structure of Diatoms .. MIcROSscory. Boecker’s Air-pump Microscope (ig. 7) .. Improved Griffith Club Microscope (Figs. 8-10) “ Midget” Microscope (Fig. 11) : . Microscopes for the Examination of Divided Circles (Figs. 12 and 13) Abbe’s Camera Lucida... ae ier iaars of Nobert and of Doyere and ofl ititne-Faveards (Figs. 1 14 and 1 senor Grunow’s Cainer Tnicthdys ie ene ae Oe RS ae ea Objectives of Large Aperture a ad ear ae Abbe’s Method of Testing Objectives (Figs. 16-19). ase Sioa et Hardy's Chromatoscope (Figs. 20 and 3B eas Dees Oe Gundlach’s Substage Refractor ..~ .. Ue gir Be oa ag, Cee eas Tolles’ Frontal-prism Illuminator (Fig. 22) ESS ET I ee EN Warm and Moist Stages (Figs. Be 7?) Sh Tine ta eis i‘ Dibdin’s Hot Stage .. .. . x Caton’s Fish- Sinaigh (Fig. 26) = Here Dayton’s Modification of the Winhain Half- disk Illuminator igs 27-28) Carbonic Acid as a Narcotic for Marine Animals .. .. .. Keates Corallin as a Microscopical Reagent ets bast ebicesaiy oe gary, Ses NRL a Preparing Bacillus twherculosig «1 4 be we oe we ee ee as Staining Bacterta oi ee ee ee ak ic ne 8 | Nay eee om 3 Préparing Fatty Acids. ve ye) ne oe nee owe) ee aw Carmine Solution sis’ Salis ha nay ire ee Prussian Blue and Safranine for Plant-sections .. sae tea Na eer ee ea Injection Masses .. mig Se 9 bod ones SO Taylor's Freezing ‘Microtome (Fig: 29) Peet hes Sey e's | the mena Mounting Media... « Re She BATA Preparation of Dammar Varnish FeO SUE PEt ea Hunt's American Cement .. Ma eT ETE al een Cee er eRe eH, ih Mayer’s Water Bath (Fig. 30) Ug UTE aR EONS gyi Gala Satie bal agi hang no Packing Slides for Travelling .. BP Fe hige Tea eae Ca ANS SDE Examination of Living Germs in Water... 1. oe vn ee ke tk ee Sinel’s Embryological Slides... Teh TANG rp ek Site hy Care Search for “ Atlantis” with the Microscope Sapo Lae At ey Glee a hie Oole’s Studies in Microscopical REIONOD Nae ees ceive Wire ea es PROOBEDINGS OF THE SOCIETY ete eee ROYAL MICROSCOPICAL SOCIETY. COUNCIL. ELECTED 8th FEBRUARY, 1882. PRESIDENT. Progr, P. Martin Duncan, MB., F.B.S. VICE-PRESIDENTS. Rosert Brarrawatrs, Esq., M.D., M.BR.CS., F.LS. Roszrt Hupson, Esq., F.RS., F.LS. Joun Ware Stepuenson, Hsq., F.R.A.S. : TREASURER. Lionsn §. Beatz, Esq., MB, F.RCP., RS. i SECRETARIES. Cuartes Stewart, Esq., M.R.CS., F.LS. FRANK a me LL.B., B.A, V.P. & Treas. LS. - Twelve other MEMBERS of COUN IL. -Lupwie Drevrus, Esq. Cuartes James Fox, Esq. James GLaisHEr, Hsq., F.R.S., FRAS. J. Witiiam Grovzs, Esq. A. pg Souza Gumrarazns, Esq. Joun E. Inepey, Esq. — Joan Mayan, Esq., Jun. Atpert D, Micuann, Egq., F. LS. Joun Minar, Esq., L.B.C.P.Edin., FE.LS. _ Witu1am Txomas Surrorx, Esq. _- Frepericx H. Waxp, Esq., M.R.GS. - ‘T. Caanrers Warre, Esq., M.R.C.S., F.LS. ( 6) I. Numerical Aperture Table. The “ APERTURE” of an optical instrument indicates its greater or less capacity for receiving rays from the object and transmitting them to the image, and the aperture of a Microscope objective is therefore determined by the ratio between its focal length and the diameter of the emergent pencil at the plane of its emergence—that is, the utilized diameter of a single-lens objective or of the back lens of acompound objective. This ratio is expressed for all media and in all cases by n sin uw, m being the refractive index of the medium and w the — Semi-angle of aperture. ‘The value of n sin w for any particular case is the ‘numerical aperture” of the objective. Diameters of the Angle of Aperture (=2 w), Theoretical ; Back Lenses of various Wouinerical ! Tilumi- Resolving ee Pian tpnerion, | peruse: | ony | ifr, [Homage wating | Dome i | SAGs ne sa (nsin u=a.)| Obj-ctives, | immersion) Immersion ower. | Lines to an Inch. Power (4 in.) eed Objectiyes,). Objectives. | (a2.) (A=0°5269 w from 0°50 to 1°52 N. A. tree \(r = 1°33.)) (7% = 1°52.) =line E.) a 1°52 5 si 180° 0’ |2-310} 146,528 | -658 1:50 bs Ke 161° 23! | 2:°250 144,600 “667 1°48 o a 153° 39’ | 2:190 142,672 *676 1°46 of es 147° 42’ |2:132 140,744 "685 "44 a8 * 142° 40’ | "42 o Se 138° 12’ ‘40 vie oe 134° 10’. | °38 +s as 130° 26' ‘36 oe at 126° 57' "34 eis ae 123° 40’ ‘33 vs 180° 0'| 122° 6 "32 oi 165° 56’| 120° 33 °30 ve 155°..88"|.. 117° -34'.| *28 Se 148° 28’) 114° 44’ "26 as 142° 39!) 111-59! "24 A 137° 36'| 109° 20’ "22 oe 133° . 4"| 106° 45! *20 128° 55’| 104° 15° ‘18 res 125° 3’) 101° 50’ "16 ve 121° 26’) 99° 29° 14 AS 118° 00’}. 97° 11’ “12 Ss 114° 44") 94° 56’ ‘10 ms 111° 36") 92° 43° ‘08 Sis 108° 36’! 90° 33’ ‘06 “A 105° 42’| 88° 26' "904} 133,032 “725 *850| 131,104 *735 “796 | 129,176 “746 “690 |. 125,320 *769 123,392 “781 *5388 | 119,536 *806 Peer ft fet ed ek fe ed ft fred ed fd fre el ed feel fet ed et et EO DD DO HO HO for) oo oO +892) 113,752 *847 ‘94 140°. 6’ | 89° 56’) 76° 24" | +884 90,616 ‘92 133° 51’ | 87° 32’| 74° 30’ | “846 88, 688 ‘90 128° 19’ | 85°.10'| 72°: 36’ | +810 86,760 ‘86 118° 38’ | 80° 34’| . 68° 54’ | -740 82,904 "84 1149). 190) S782, 202} 672 2 Be 706 80,976 “82 110°°10' | 76°. 8'| » 65° 18’ | 672 79,048 : 6 ‘76 98° 56’ | 69° 42"; 66° 0’ | :578 73,264 | 1 316 74 95° 28’ | 67° 36’| 58° 16’ | +548 71,336 1:351 “72 92°. 6’ | 65° 32’) © 56° 32' | -518 69,408 1°389.- “70 88° 51’ | 63° 31’; 54° 50’ | +490 67,480 | 17429 ‘68 85° 41’ | 61° 30’| 53° 9’ | +462 65,552 Piles *70 ‘66 82° 36’ | 59° 30’) 51° 28’ | +436 63,624 1515 64 79° 35’ | 57° 31'| 49° 48'| +410] 61,696 | 1-562” ‘62 76° 38’ | 55° 34] 48° 9°| +384/° 59,768 | 1-613. ‘60 73° 44'| 53° 38'| 46° 30'| +360! 57,840 | 1-667 35 55,912 | 1724 43° 14’ | +314|. 58,984 | 1786 41° 37' | :292| 52,056 | 1-852. 40°. 0'| -270| 50,128 | 1-993 © 38° 24’ | +250). 48,200 | 2-000 — a 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 10) ae 147° 29" j.-929.-24") - 78° 207 | #922 92,544. | 1/042 0 18) 0 0 18) 0 0 0 18) 18) Oo 0 10) 19) 10) .o) Oo =) or @ ~] i) ce) or me or _ ° ~ Nm a M6 or Px, oo os ior) ‘074| 188,816 "694. ‘016| 136,888 “704 *960|} 134,960 “714: % ‘770 128,212 | °752 -742| 197,248 | +758" ig 1 1 ‘88 1239 175 822 51") 70? 440 Vc 774 84,832 1:136 > 1 : 1 1 -80 106°. 16’ | 73° 58’| 63° 31’ |. -640| © 77,120 | 1-250 - 78 102°. 31’ | 71° 49'| 61° 45’ | -608| . 75,192 | 1-982 — “588| 121,464 | +794 > : “ °488} 117,608 *820 *440| 115,680 *833 — -B46| 111,824 | +862. -300| 109,896 | +877 -254| 107,968 | +893. -210| 106,040 | +909 166} 104,112 | +926 © ‘124| 102,184 | 943 — -082| 100,256 | +962 -040| . 98,828 |. -980 — . 000} 96,400 | 1-000 ‘98 | 157° 2 | 94° 56’| 80° 17'| -960| 94,472 | 1:020 | Examrpre.—The apertures of four objectives, two of which are dry, one water-immersion, and one oil-immersion, ¥ would be compared on the angular aperture view as follows:—106° (air), 157° (air), 142° (water), 130° (oil)... "80 "98 1*26 1°38" or Their actual apertures are, however, as numerical apertures. thelr ieale showing he relation of Millimetres, c., to Inches. EEL CLEP UE EEE E ELLER LEEEELL NE BN Ke PT RN eS QR ERIE ARG a SEC I | I I eg Se nin) secs TY pat EL 5 TITHIFIIUIT TILL TEER PEE TEPC are ie DE a 2 _po. ma Jans 5 ond oy ee {0 * eRe = SERA - Ur Baie o. Setar eet ret eye, SOGK on CBT ey eed . ! & ‘a =] mm, mm,=1 cm, Jem. =1 dm f II. ee : KH OO OSIOP WOH = 12 13 14 15 16_ 17 18 19 20 21 99 23 24 25 a6 37 28 29 30 31 32 33 24 35 36 87 38 39 40 41 42 43 44 45 46 47 48 49 50 60 70 80 80 100 200. “|, 800 {| 400 600 600 760 800 900 ae Conversion of British and Metric Measures. |] mm. SO (9 cm.) | 100 (10 cm. ins, 3° 937043 7874086. 11811130 15° 748173 19°685216 ins, “007892 047262 086633 126003 * 165374 *204744 244115 * 283485 *322855 * 362226 *401596 *440967 480337 *919708 *909078 598449 *637819 *677189 716560 795930 *795301 *834671 *874042 *913412 *952782 *992153 *031523 70894 *110264 +149635 *189005 *228375 "267746 “307116 *346487 *885857 *425228 464598 *503968 043339 582709 622080 “661450 “700820 ‘740191 MN NPNWNMNPNPNHW HNNMNMNWNHMNbN bw ty COD C207 0o Coqpepcoco eco coco C9 09 09 69 bo DO bh bo bo bo . 8°779561 3°818932 3°858302 3°897673 |. =1 decim.) 23622259 ~ 27559302 31°496346 35° 433389 i.) Linea. Micromillimetres, §c., into Inches, &c. ins. mm. ins, -000039 1 *039370 *000079 2 *078741 °000118 |- 38 *118111 -000157 4 *197482 “000197 baka *196852 "000236 6 * 236223 *000276 @ * 2759593 7000315 8 *314963 *000354 9 *394334 -000394 | 10 (1em.) °393704 *000433) iL *433079 *000472 | 12 *472445 -000512 | 18 *511816 *000551'| 14 *501186 *000591 | 15 *990556 “000630 | 16 *629927 *000669 | 1'7. *669297 *000709 | 18 *708668 *000748 | 19 *748038 ‘000787 | 20 (2em.) .+787409 “000827 | 21 *$26779 -000866 | 28 °866150 °000906 | 28 *905520 ~ *000945 |. 84 *944890 *000984 | 25 “984261 -001024 | 26 1:0236381 “001063 | 37 1°0638002 -001102'| 28 — 1:102372 ~*001142 | 89 1°141743 “001181 | SO (3. cm.) 17181113 -001220 |} 81 1°220483 *001260 | 82 1: 259854 *001299 | 33 1°299224 ‘001339 | 834 1:338595 *0013878 | 35 ~1°377965 °001417 | 36 1-417336 -°001457.) 37 1°456706 *001496 | 88 1°496076 “001535 | 89 1°535447 *001575 | 40 (4 cm.) 1:574817 -001614 | 41 1°614188 “001654 | 42 ~ 1°653558 *001693 | 48 1°692929 ‘001732 | 44 1°782299 *001772 | 45 1:°771669 001811 | 46 1*811040 ‘001850; 4'7 1:850410 001890 | 48 1°889781 “001929 | 49 1:929151 “001969 | 50 (5 em.) 1°968522 *002362 § *002756.4 decim. ~ 008150 1 *003543° 2 ~*003937 3. “007874 4 *011811 | 5 *015748 6. ~*019685 v4 *023622 | 8 027559 | 9 "031496 1 035433 } din, =1 metre | 1000 (=1 mm.) cs 10(1 metre) 39°370432 3°280869 ft 1°093623 yds. Lnches, §¢., into Micromillimetres, | a] a} 9 cnr OleOle oO) ol s| of o B) tO) <=) iJ.) t-)) é| Cle o| | 1S) {>} eS) Zecmateo|e a ol ol I J ti) a colt 5 webs ale ba AlMop= oe B|H onl sleet bat bee S| i le est ala | ) o} Blacks CHOIR Whe lyd.= ge. be "015991 *269989 *693318 *D39977 *822197 *174972 *628539 *2383295 *079954 *349943 *466591 *699886 *399772 mm. 028222 °031750 *036285 *042333 -050800 *056444 *063499 *072571 084666 *101599 *126999 *169332 *253998 *907995 SUD COO Ot 00 09 DD De et et be 9°524915 em, 1.111240 1°269989 1°428737- 1°587486 1°746234 1+904983 2:063732 2°222480 2°381229 -2°539977 5°079954 7:°619932 decim. 1:015991 1°269989 1°523986 1°777984 2°031982 2°285979 2°539977 2°793975 3°047973 — metres. “914392 “_—_ 8 — -sommmesSoTIy S6SECh. = LOBES -F *sauIUTe130309T, FELEFES «3 *soTUMB.SvoIp C686LF +9 ‘SOURS C686LP-9 9061E8-S 9T6E8L-G LG6SES-F LE6L88-€ SF66E6-S SE616S-3 696EF6-1 616666 -T *SOULULBASIOOp C686Lh-9 900TE8-S 9T6E8L-S LZ6GES - F LE6L88-& 8t66E6-6 SS6I6E +3 696EF6-T 646966 - 1 *SOTALUIB.131}U99 C686LF-9 9U06TE8-S 9T6E8T-S LG6SES + F LE6L88-& 8h6686-E SS616G -Z 696876 -T 616966 +1 686LT9- *SOTLUBISI] [TUL CqI D (:z0 [) “1TOAv ‘of ‘sommoubyppy opue “of ‘sumey 000L : 0Z9F0G-G *“IIOAR "SQ ¢. LEP | F6EL26-E Oot 6SLECS - *1LOAB “ZO 6FESEP-ST FII688- ET 6LEGFS +41 #49608 - OT 60F6S6-6 © PLIQTL-L 6E62LL-9 GOL6G9-F OLF980-§ CScErs-1 rt AMHIoSr- DHS pos LL6888-T 88SFEs-T #96080 +1 1F6S66- LI9TLL- F6GLIO- OLOZIF- LE980E- GEPFSI- T688E1- 6SFEGI- LO. 9Z080T- 90: F$69660- c0- G9TLLO- F0- 6GL190+ 60- LOGOFO: G0. ¢98080- TO: GEFSLO- *survis *SULLIS jor) on A SO HIS 6 ECO SD D cS “LHDIDA (g) Caso 1) =~ ON00T (-180;~90q 1) —000T (ase09p T) 00 (‘13 1) i ra N OO HID Or DH “sae IS1ep (-t5100p T) 00T 06 (‘1o1}090 [) or MANO HID OMe HO “SOTMUABASIT UL ‘of ‘supp opur “of ‘sommnsbypyr “SOTJIT FSCEEC-F = CMPS 1) FLZ-LL] -G99889-T . OOF 96LPLF-T 06 Og60TS-T 08 FOOLFL-L ~ OL “SeI}TT ; FLELES-6 09 ITSS6T-8 0s 6F9FSS-9 OF L86S16-P 0§ CCELLZ-S 06 699869-T : Or 96LPLE- TE OS60TE -T PIOLFT-T “sorjploep FLOLE8 +6 TLIES6I-8 6F9FGS +9 L86S16.F GCSLLG-S 69989 -T 96LELF-T OS60TE-T FIOLFI-T *sor}|]I}U00 FLOTES -6 ITES6I-8 6F9FES-9 L86S16-F CCELLG-S 69989-T "SOT “sul ‘qno ‘of Ssoupuiyy opus “of ‘sayouy orgn mA OO sH 1d 60 ~-DO Wet AMNCD HIND MOD, ‘ponumjuoo—SEANSBEW OlIZOWL PUB YSTIIg JO MOTsIeATIOD ‘s[[e3 16002: ‘spurd FZL09L-1 Ml ‘yy ‘qno. cIgcg0- = L8E6Z0-19 SF86G6- FS 608028 -8F TLLLIL-GF GSZS19-9E 6961S - 0S CCLOLF- 46 9T9LOE-8T LLOGSOG- 61 6801-9 C8GZ6F -S TS0G88 - F LLLILZ °F ScS199-€ 696190 .& CLOLFF-S G9L0E8 -T 806066. FSZO19- 8ZC6FS- S0Z88F- SLILGF. GST99E - LOTS0s- GOLFFS- 9LOE8T- TSOZ6T- CZOT90- *suy “qno (e171 1) 0001 006 008° 00L 009 00¢ 00F 00g : 00 CTosp 1) 00r 06 0g (1089 1) OT rm OID HIN OPO *SO1}A TTYL “of ‘soyour orgng opm “of ‘soumpypeyy *“ALIOVAVO ('Z) aes Cage) _ Tif. Corresponding Degrees in the || IV. Refractive Indices, Dispersive Fahrenheit and Centigrade Powers, and Polarizing ~ Scales. Angles. eaaay oat Fahr. (1.) Rerkaotive Inpiczs. ie) fo} fo} 260° 0 100 212°0 23222 98 208-4 Diamond 204:44 96 204°8 176-67 94 Bora |e ees 148-89 92 197°6 Bisulphide of carbon 121-11 90 194-0 Flint glass 100-0 88 190-4 es 98-89 86 196+8 || Crown glass 96°11 84 183:2 Rock salt 98°33 82 179°6 deenate 90-56 80 Wee eo ee 87°78 78 172-4 Linseed oil (sp. gr. -932) 85°0 76 168°8 || Oil of turpentine (sp. er. -885) 82°22 74 165-2 79:44 72 16ke6 +|) coho! = 76°67 70 158-0 Sea water ) 73-89 68 154-4 || p Ba 71°11 66 Gel ee s 68°33 64. 147-9 ||. Air (at 0° C, 760 mm.) eS 65:56 62 1436 wee E 62°78 60 140°0 F 60:0 58 136-4 (2.) DIspPERsIvE PoweErs. a 57°22 56 132°8 z n 4-44 | 54 129-2 || Diamond 2 51°67 52 125°6 Phosphorus =] 48°89 50 122-0 ; - ae) 46-11 48 118-4 Bede of carbon = 43°33 46 114:g || Flint glass @ 40°56 44 111-2 || Crown glass ar) 37°78 42 107°6. |: Reck coe 35:0 40 ~ 104-0 AS a 32°22 - 38 100-4 Canada balsam rs) soe a oe Linseed oil (sp. gr. +932) s 93°89 39 89°6 Oil of turpentine (sp. gr. -885) o) 21:11 30 86:0 Alcohol GAS 3 18-33 28. 82-4 ac! 15°56 26 eg |) hoe water : 12:78 24° 75°2 Pure-water & ‘10-0 22 71:6 Aim 2 . 7-22 20 68°0 : . ; 4:44 18 64-4 (3.) Powarizine ANGLES, ’ 3 1:67 16 60°8 & 0:0 14 o7°2 Sil » eer 12 525 4 Demonde 2 — 3:89 10: (50 0 Phosphorus i naan A | fog || Bisulphide of carbon os = 12°22 we 39-9 || Flint glass. = ees 2 35°6 Crown glass — 17:°7 0 A 32° 0 oie: j ig aes ano 98°4 Rock salt SPIO eR ipl Geena. 9 94-8 Canada balsam : Peat hen esl 21-2 || Linseed oil (sp .gr. 932). = 28°89 Jo 8 17°6 ee — 31-67 | = 10 ay Oil of turpentine (sp. gr. -886) — 34:44 | — 12 10°4 || Alcohol — 37:22 ; — 14 68 — 40:0 = 46 3:9 Sea water — 42°78 | — 18 — 0-4 || Pure water — 45:56 | — ~.4:0 - Air ( 10 ) V. Table of Magnifying Powers. Zz OBJEC- | TIVES. _ EYE-PIECES. Beck’s 2, & Beck’s 1, | Powell’s 2, Beck’s 4, Beck’s 5 4 Powell’s 1, and Powell’s 3.} Ross’s C. | Beck’s 3. } Powell’s 4, %. | Powell’s5.§ Ross’s Fo Ross’s A, | Ross’s B, Ross’s D, Ross's Ee [ s [a nearly.* Focat LENGTH. Macniryine Power. = 20 | 25 | 30 ej eae Fs ss BAe | A zi ats Ea cs =| ins, | 5 2 | 10 4 23) 123 3 32) 162 2 5 | 25 13 65) 331 i 10 | 50 |; 123] 623 3 132] 662 eS oe to 75. 3 20 100 |. 25 125 2 30 150 #3,| S33] 1662 3 40} 200 2] 50 250 2 60 300 i}. 70 350 ; 80 | 400 1| 90] 450 ge, 100 500 <8 110 550 ae 120 600 z;| 180 650 ve 140 700 zs| 150 | 750 2, |160] 800 3,| 170] 850 3; | 180} 900 3;| 190] 950 3; | 200 4 1000 2.| 250 | 1250 4; |800}1 1500 3;|400 |} 2000 Zz; |500]] 2500 2;| 600 } 3000 2s {800 |} 4000 AMPLIFICATION OF OBJECTIVES AND EYE-PIECES 15 183 25 374 50 75 932 100 1123 150 1873 205 250 300 375 450 525 600 675 750 825 900 975 1050 1125 1200 1275 1350 1495 1500 1875 2250 3000 3750 4500} 6000 10000 | 12000 40 | 50 662 100 1332 200 250 2662 300 400 500 600 6662 800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000 3200 3400 3600 3800 4000 5000 6000 8000 10000 12000 16000 COMBINED. 25 30 313 372 | 412 50 622 15 83: | 100 125 150 156} | 1873 1662 | 200 1873 | 225 250 300 3123 | 875 375 450 4162 | 500 500 600 625 750 750 900 875 | 1050. 1000 | 1200 1125 | 1350 1250 | 1500 1375 | 1650 1500 | 1800 1625 | 1950 1750 | 2100 1875. | 2250 2000 | 2400 2125 | 2550 2250 | 2700 2375 | 2850 - 2500 | 3000 3125. | 3750 8750 | 4500 5000 | 6000 6250 | 7500 7500 |} 9000. * Powell and Lealand’s No, 2 = 7°4, anid Beck's No. 2 and Ross’s B= 8: respectively #, less and J more than the figures given in’this co 50 60 622 75 83: {| 100 125 150 1662 | 200 250 300 3122 | 875 3332 | 400 375 450 500 |. 600 625 750 750 900 8332 | 1000 1000 1200 1250 1500. 1500 1800 1750 | 2100 2000 | 2400 2250 | 2700 2500 | 3000 | 2750 |. 3300 3000 | 3600 | 3250 | 3900 3500 | 4200 | 3750 | 4500 4 6¢ 4000 | 4800 4250 | 5100 4500 | 5400 4750 5700 5000 | 6000- 6250 | 7500 7500 | 9000 10000 | 12000 } 160 12500 | 15000 - 15000 | 18000 © 20000 | 24000 | : nifying power, or ( u ) Gopal Microscopical Society, MEETINGS FOR 1888, At 8 Pm. 1888. Wednesday, January .. .. «2 «+ os « 10 - FEBRUARY EES eo Can er ime ee © & (Annual Meeting for Hleetion of Officers and Council.) i Mani 8A ae le a eee Pe APR te ee ae at Ses Ne Pew Le ea ME ee ee ee ae eee me DUN ret ee oe eee a < OctToBER SEs coped eager, a ee A NoyaMnig fos bo ek SR ee eA 55 Pyucemari.’ =. o ooo bigs Bate ae THE ‘SOCIETY’ STANDARD SCREW. The Council have made arrangements for a further supply of Gauges and Screw-tools for the “ Soorery ” Sranparp Screw for OsysEorives. The price of the set (consisting of Gauge and pair of Screw-tools) is 12s. 6d. (post free 12s. 10d.). Applications for sets should be made to the _ Assistant-Secretary. or For an explanation of the intended use of the gauge, see Journal of the _ Society, I. (1881) pp. 548-9. - . _ ADVERTISEMENTS FOR THE JOURNAL. _ Mr. Cuaruzs Brznoowz, of 75, Chancery Lane, W.C., is the authorized Agent and Collector for Advertising Accounts on behalf of the Society. (mR) CHARLES COPPOCK, WHOSE PARTNERSHIP WITH Ri od. BECK; HAS CEASED BY EFFLUXION OF TIME, WILL CONTINUE HIS BUSINESS AS A MANUFACTURING OPTICIAN, IN HIS COMMODIOUS PREMISES 100, NEW uN STREET, LONDON, W.; Materials for the preparation of Microscopical Objects, and all Scientific Instruments will =, be supplied upon the most aN reasonable terms. And not only , supply the Instruments manufactured a by his late firm, and | those of American and Foreign models, but those of the most recent and cheaper ¢ forms demanded by : a FULL CATALOGUE \ _- WILL BE ISSUED \ \ 2» WITHOUT DELAY. Amateurs and Histo- logical Students. Notably one constructed to data, derived from his late experience obtained in OCULISTS’ PRESCRIPTIONS RECEIVE PERSONAL ATTENTION. 100, NEW BOND STREET, LONDON, W. SOc. SER.II.VOL.IL PL.I. IRG C JOURN. R. MI Care a: “Sera ania West Newman & C2 imp. Michal ad nat, dely WRhein 0c Anatomy of the Oribatide. ye” ~~ » aa i ges A wy, oe “oe “1 _ * AD.Michael ad nat, del. WRhain se. JOURN. R. MICR. SOC. SER.I. VOL.M By \ Anatomy of the Onibatidie:, i 2 JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY. FEBRUARY 1883. TRANSACTIONS OF THE SOCIETY. I.—Observations on the Anatomy of the Oribatide. By A. D. Micuast, F.LS., F.R.MS. (Read 10th January, 1883.) Puates I. anv II. In preparing the work upon the British Oribatidz, which I am now writing for the Ray Society, it became desirable to deal, as far as I was able, with the leading features of the anatomy. It was EXPLANATION OF PLATES I. anp II. Puate I. Fic. 1.—Alimentary canal of Nothrus theleproctus. xX 50. a, cesophagus; 5, ventriculus; d d, ceca; e, small intestine; f, colon; g, rectum; 77, anal plates; 77, preventricular glands. 2.—Alimentary canal of Hoplophora magna. x 50. Same lettering. 3.—Alimentary canal of Dameus geniculaius. x 35. Same lettering, and ¢, ingluvies; A, labium; /, maxille; m, palpi. 4.—Part of the alimentary canal of Leiosoma palmicinctum. Same letter- ing, and m7, supposed ducts from preventricular glands. 5.—Ending of trachea in the acetabulum of the third leg of Dameus geniculatus. x 100. a, acetabulum, removed from the ventral plate; 6, coxa; c, femur; d, trachea, ending in a small air-sac in the acetabulum. 6.—Two trachez of Dameus geniculatus, uniting into a single trunk before their attachment to the acetabulum of the second leg, 7.—Air-sac near mouth of Nothrus theleproctus. x 350. 8.—A portion of the left side of Leiosoma palmicinctum, the dorsal shield and all the internal organs, except the super-coxal gland, having been removed. a, wall of rostrum; 4, first leg; c, second leg; d, veutral plate; e, super-coxal gland. 9.—The super-coxal gland of Leiesoma palmicinctum. x 350. a, gland; ___6, globular body (vesicle ?). », 10.—Mandible of Oribata globula (ordinary type in the family). x 180. », 11.—Mandible of Pelops pheonotus. x 600. Type of the genus Pelops. 5, 12.—Mandible of Serrarius microcephalus. xX 250. ;, 13.—Serrated end of same mandible. x 500. 5, 14.—Two teeth of same mandible, highly magnified. [Prate IT. Ser. 2.—Vot. III. B 2 Transactions of the Society. a subject upon which there were practically only three existing authorities. The first of these is Dujardin,* a keen-eyed observer, who saw a good deal, but unfortunately, as far as the Oribatide are concerned, drew conclusions from what he saw which have formed a stumbling-block for most later writers. The second is Nicolet, + and this may be treated as the only substantial work upon the subject. The third is Claparéde,t whose work is excellent as far as it goes, but it only deals with one very ex- ceptional species of this family, and that with a view to the development rather than the anatomy. When I first commenced, my idea was simply to verify Nicolet’s work before repeating his account in my own book; and to ascertain that it was correct, not only for the one or two species he had described, but also for others. As I advanced, however, I found so much variation in different forms, and so many points upon which I was not able to coincide with Nicolet’s descriptions, that I was led to devote the greater part of my leisure during the . summer and autumn of 1882 to the investigation: it has been Puate II. Fic. 1.—Male reproductive system of Nothrus theleproctus. x 50. a, a, lobes ” ” of the testis; 5b, flat portion, possibly vesicula seminalis; cc, vasa deferentia; d, ductus ejaculatorius, with penis, penial skeleton, and sclerites, &c. 2.—Penis and penial skeleton and sclerites of same species. x 600. a, penis. 3.—Penis of same species, side view. x 1500. 4.—Semen of Dameus geniculatus. x 1800. 5.—Female reproductive system of Oribata lJapidaria, taken when the creature has just emerged from the nymphal stage. x 40. a, ovary; bb, oviducts; c, vagina; d, ovipositor; e, genital plates; f, anal plates. 6.—Female reproductive system of Cepheus tegeocranus, mature, showing the oviducts full of eggs. x 60. Same lettering. 7.—Female reproductive system of Dameus geniculatus, mature, ovary nearly exhausted. x 50. Same lettering; and g, globular ex- pansion of oviduct ; 4, copulative suckers (so called) ; 17, tendons to genital plates; 77, muscles attached to same tendons, 8.—Portion of the ovary and portion of oviduct of same species, up to and including the globular expansion. x 120. Same lettering. 9,.—End of trachea in acetabulum of leg of Leiosoma palmicinctum. . “it a, edge of acetabulum; 4, coxa; c, trachea; d, muscles of leg. 10.—Anal sac of Nothrus theleproctus. x 100. aa, sac; 6b, genital plates ; ec, anal plates. * “Premier Mémoire sur les Acariens,” Ann. des Sci. Nat., 3rd ser. iii. p. 5. Journal de l’Institut, 1842, p. 316. + “ Histoire Naturelle des Acariens, qui se trouvent aux Environs de Paris,” Archives du Museum, vii. (1855). Paris. ¢ “Studien an Acariden,” Zeitschr. f. Wiss, Zool., xviii. (1868) p. 446. Observations on the Oribatide. By A. D. Michael. 5) suggested to me that the results may be of interest to one of the biological societies, I have therefore described some of them in the present paper, instead of waiting to include them for the first time in the future treatise. I do not propose, in these pages, to give any exhaustive account even of such portions of the anatomy as I am acquainted with, that would be hardly fitted for this Journal, and would certainly be too lengthy, but I shall confine myself to such portions as seem to me to be undescribed, or to vary sub- stantially from Nicolet’s account, and to such other parts as are necessary to the comprehension of the novelties. It is only fair to Nicolet to point out, that, in his beautiful work above quoted, he states, that, in consequence of the minute size, and the hard, opaque, chitinous, exo-skeleton of these creatures, he found the internal anatomy extremely difficult. Claparéde gives a similar reason for scarcely touching upon the internal anatomy. There cannot be any doubt that Nicolet and Claparéde were right as to the difficulty. The largest specimens are under a millimetre in extreme length, and many of the species which I have dissected are not above half that size; they are possessed of a chitinized cuticle which is nearly as hard and as brittle as glass, and which is usually quite opaque at all times except immediately after the ecdysis. I first tried observations at that period, but { soon found that 1 could not obtain much information this way, for, although, now that I am acquainted with the organs, I can frequently recognize many of them through the dorsal plate during its short period of transparency, yet the view is too imperfect, and the organs too much hidden by one another, for original inquiry. I endeavoured to stain them whole, but entirely failed in getting any stain to penetrate the chitin of the exo-skeleton, or even to run in at joints, stigmata, &., although I tried the air-pump, hoping it might assist. Finally, after a not very satisfactory attempt at section cutting, I determined to face the difficulty of the small size, and to rely entirely upon actual dissection—these notes are the result. I soon found, that, in order to produce a successful dissection, the creature must be in good, healthy, condition; it must not have been kept long in confinement, and it must be dissected immediately after death. The dissections have, in each instance, been frequently repeated, i.e. upon a considerable number of specimens of each species, as, in consequence of the difficulties, the naturalist would be too liable to error in judging from one or two instances. All the figures are made from actual dissections, they are not calculated, or put together, from the result of consecutive sections, The preparations from which the drawings are made, are, in almost all instances, now in my possession, stained with logwood, and B 2 + Transactions of the Society. mounted for the Microscope, so that their appearance can easily be verified by any one interested in the subject, although of course different opinions may be entertained as to the correctness of the conclusions which I draw from them. The dissections have chiefly been made under a Stephenson binocular, with powers varying from an inch to 3 in. and low eye- pieces; they have, however, in cases requiring it, been verified and examined under amplifications running up to over 1000 diameters. I think I may say that the tendency of my mind has been a desire to confirm previous writers, and not to upset their state- ments. Where I am not able to agree with them, it is that I have failed to obtain the same result, and that the actual organs before me do not seem to me to agree with the accounts. The principal differences which I find in the internal organs are in the respiratory system, and the reproductive system. I find differences of lesser importance in the alimentary canal; and I believe that I have traced some secreting organs not before re- corded ; these are the points upon which I intend to touch ; and, finally, I shall mention two matters in connection with the exo- skeleton which seem to me to be worthy of notice. It is necessary to describe the alimentary canal in order that the varieties, &c., which it displays may be understood, although Nicolet figured the greater part of it correctly in one species. The Alimentary Canal. In the Oribatidx the alimentary canal is somewhat short and simple, that is to say, there is a comparative absence of convolu- tions in the hind-gut, and the very numerous cecal prolongations of the mid-gut found in many allied groups, as the Aranea, Picnogonida, &c., are reduced to two, which, however, are usually of great size and importance. The proportions of the parts of the canal, and the size and arrangement of the ceca, vary greatly in different species, but, as far as my experience goes, the divisions of which it is composed are always the same. I say “as far as my experience goes, because I have not dissected anything like the whole of the species. The canal is composed of the cesophagus, the ventriculus, a short small intestine, the colon, and the rectum, terminating in the anus and anal plates ; of these the two first are almost horizontal, and are placed in a straight median line near the dorsal surface; the small intestine turns downward and slightly forward, and the colon and rectum are more or less perpendicular, and lie beneath the ventriculus, or almost so; the result of this is, that, when the dorsal shield is removed, the cesophagus and the ventriculus, with its Observations on the Oribatide. By A. D. Michael. 5 czca, are usually the only parts of the canal seen. The canal is, of course, firmly attached round the cavity of the mouth, and at the anus, but in other parts it seems to float freely in the general body-cavity, with only very slight attachments, if any. If the cesophagus be cut away from round the mouth, and the rectum from round the anus, a hair may easily be passed under the canal, and its whole length be drawn out on the hair without further injury. Taking Nothrus theleproctus as a convenient type :— The esophagus is a long, thin, almost straight, tract of the canal, extending from the mouth to the ventriculus, and having its lowest point at the former and its highest at the latter. It has thin walls, capable, however, of considerable expansion and contraction. The cavity of the mouth being larger in diameter than the lumen of the cesophagus, the latter necessarily widens somewhat as it approaches the former, and the widened portion might, not unfairly, be termed the pharynx; posterior to this the cesophagus continues of almost even circumference for the greater part of its course through the cephalothorax ; near its posterior extremity it widens, in some species this enlargement is considerable, and then forms an ingluvies or crop, the jabot of Nicolet ; this writer correctly gives the ingluvies as very much developed in Damezus geniculatus, plate I. fig. 3,¢; in Damzus clavipes it 1s even more developed and is almost as large as the ventriculus. I cannot say that I have ever seen it so large in other genera, but it is no doubt quite distinguishable in many others. Nicolet also, in the same drawing, depicts the cesophagus as being constricted at short intervals by circular bands of muscle, so that it presents a moniliform appearance. I have not been able to detect this moniliform effect in any other species which I have dissected, but the bands of muscle are usual. In the ingluvies of Dameus geniculatus these circular bands of muscle are beautifully seen after the preparation has been stained with logwood, and indicate that it is an expansion of the cesophagus, not a separate stomach. Nicolet further states that an air-bubble is invariably found floating in this ingluvies ; my own observations do not quite confirm this; a large air-bubble is certainly to be seen very frequently floating in the canal, but it appears to me that it ig not by any means invariably present, and that, when present, it is more frequently in the ventriculus than in the ingluvies; it is doubtless due to the creature’s living chiefly upon liquid materials derived from vegetable substances, and absorbed by a sucking process, which accounts for the presence of liquid in considerable quantities in the fore- and mid-guts, and for those parts not being quite filled with it. The cesophagus continues the whole length of the cephalothorax, and passes a very short distance into the abdomen; it is sharply 6 Transactions of the Society. constricted by a circular muscular arrangement at the point where it enters the ventriculus, forming a very perfect valve, which prevents any food material from returning from the ventriculus to the cesophagus; this may often be seen very well by the air-bubble, which, carried by the liquid in which it is floating, may be observed to pass down from the cesophagus to the ventriculus, but it is always stopped at the valve whenever it has a tendency to return. The cesophagus enters the ventriculus about the centre of the anterior end, which possibly it may not be proper to call cardiac in a creature which is not known to possess any heart. The ventriculus ig the largest and most important portion of the canal; it is a wide sac, occupying from half to about two-thirds of the length of the abdomen, near the dorsal surface (plate I. figs. 1, 2, 3, 4, b). In Nothrus theleproctus the sac is of a shape approaching pyriform, the narrower end being the anterior one, this however is rounded, although smaller than the hinder part; the posterior end has a tendency to a blunt median point. The walls of this viscus are thick and muscular, more so than any other part of the canal except the rectum, and it is here that digestion doubtless chiefly takes place, a food mass may, most frequently, be seen occupying the pyloric portion. From the widest part of the ventriculus, i. e. about two-thirds of the length from the anterior end, a large czecal diverticulum arises on each side, and, in the present species, after standing outward (laterally) so as to form a shoulder, proceeds almost straight backward. These diverticula are longer than the ventriculus itself, often more than half as long again, and nearly half its diameter; they are of almost even size throughout, so that they present a sausage-like appearance; their posterior ends are rounded. There are probably greater differences between the ventriculus and cecal appendages in different species and genera of the family than are found in any other part of the canal; this is especially true of the size and form of the ceca. In Hoplophora magna they have become very small in proportion to the ventriculus, which is widest anteriorly, and prolonged almost to a point behind. The ceca are globular, and are attached to the ventriculus by short peduncles (plate I. fig. 2, d). I mention this species, as Nicolet figures it without czeca, which is not correct in the specimens which I have dissected. In the case of Damzus clavipes, the ceca are not any longer distinctly visible, but are mere enlargements of the outer posterior angles of the ventriculus. Damzus geniculatus is an intermediate form in this respect. Nicolet treats the ceca as being simply diverticula of the stomach, without any special office, and this probably may be the most obvious and natural suggestion; as far, however, as my own judgment goes, I doubt the correctness of the view. In the very Observations on the Oribatide. By A. D. Michael. a numerous instances which I have examined, to the best of my ability, I have not ever been able to detect food in the ceca, either in specimens dissected out or in those observed in life where the transparency of the chitin enabled me to do so, which was frequently the case; whereas it is rare to find the ventriculus or colon without food contents. In addition to this, the structure of the walls of the ceca, particularly near their distal ends, is different from that of the ventriculus, they being thicker and much more glandular, and the lumen smaller in proportion, often very narrow. ‘These con- siderations lead me to infer that their function is secretory, and not simply that of an extension of the stomach, nor would there be any- thing extraordinary in this being so, as a very similar arrangement seems to exist in Apus, Limnadia, &., the ends of the cecal diverticula of the mid-gut being differentiated to form glandular organs, and the same arrangement, carried to a greater extent, prevails among the Malacostraca, &c. If these two large diverti- cula have, as I suppose, the office of secreting fluids necessary for digestion, it would explain to a great extent the apparent absence of the so-called hepatic tubes, an absence observed by Nicolet, who remarks that he was not able to detect any liver. In connection with this subject, however, must be taken the observations which will be found below as to the presence of diffused follicles, supposed by some writers to have-a hepatic function, over the surface of the canal. The small intestine (plate I. figs. 1, 2, 3, 4, e). This portion, forming the commencement of the hind-gut, may possibly be considered as simply a portion of the colon, from which it is not divided by any valve; but as, although short, it is always present, it may be convenient to treat of it under a separate heading. The entrance to the small intestine from the ventriculus is always closed by a very efficient valve, which may occasionally be seen to open in order to give passage to the balls of digested or partially digested food. The small intestine proceeds from the ventriculus at a point lying to the left of the median line and near the pyloric end, but not actually at the end; the entrance is situated either at the edge of, or slightly on the under surface of the stomach, but its position varies a little in different species. The colon (plate I. figs. 1, 2, 3, f), in all species in which I have examined it, is an elliptical enlargement of the hind-gut, very considerably smaller than the ventriculus, and usually clearly defined, particularly at the posterior extremity, where it is provided with a constriction or valve which usually completely closes the entrance to the rectum; it ordinarily turns downward, or slightly forward, so as to be brought more or less under the ventriculus. In a dorsal view when the notogastral shield has been removed without disturbing the position of the canal, only the anterior end 8 Transactions of the Society. of the colon is seen. In my figures of the alimentary canal the colon and rectum are extended into a horizontal position so as to be seen. Nicolet in his drawing of the alimentary canal of Hoplophora magna omits this portion of the canal altogether, but he gives one enlargement of the hind-gut almost as large as the ventriculus; this enlargement I presume he intends for the rectum. I can only say that I have not found such an arrangement in any of the specimens of this or any other species which I have dissected ; indeed Nicolet’s canal differs so materially from what I have met with, that I should think that we were dealing with different creatures, were it not that the species is an extremely well marked one. The walls of the colon are far less thick and less muscular than those of the ventriculus or rectum. The rectum (plate I. figs. 1, 2, 8, g) is usually pyriform, sometimes very small where it arises from the colon, as in Hoplophora magna, sometimes larger, as in Nothrus theleproctus, but always distinctly divided from the colon by a sharp constric- tion ; in some species, as Oribata punctata, it continues small for some little distance, gradually enlarging until near the anus, at, or within a short distance of which, it is closed by powerful sphincter muscles ; the actual anal end of the rectum is attached round the opening on the ventral surface which is defended by the anal plates; a series of longitudinal muscles also arise from the posterior parts of the rectum, and are inserted in the exo-skeleton near the anal plates; they doubtless assist in supporting the rectum and holding it in its place, and probably also assist in defecation. The rectum itself is muscular, with the bands of muscle arranged circularly ; this is very clearly seen in Nothrus theleproctus, where, as in the last-named species, the constriction is some little distance from the anal plates ; the portion of the canal between the two is comparatively very thin and delicate. The Accessory Glands.—There are two conspicuous glands, not I believe mentioned by any author, which I propose to call the “ preventricular glands” ; they frequently show like two black spots through the dorsal surface, when at all transparent, particularly in the nymphs, but they are seen equally well in the adults when the chitin is not too opaque, and they appear to me to be always present. When dissected out they are found not really to be black but to vary in colour from deep yellow to dark brown. These glands are shown in plate I. figs. 1, 2, 3, 4, 7, and are seated on the ventriculus at its extreme anterior part ; one on each side of the cesophagus, just where it enters the ventriculus. The edge of each gland is on the dorsal surface of the ventriculus; so that, from the dorsal aspect, they look globular, and often are so, but more frequently they are somewhat flattened and show a tendency Observations on the Oribatide. By A. D. Michael. 9 to a bilobed form, in which case they extend down the side of the ventriculus as far as their size renders necessary ; they are composed of large, loosely aggregated cells, and are easily broken up if disturbed in most species. Two similarly placed glands appear to exist in such Vermes as Prorhynchus fluviatilis. It was some considerable time before I could trace the ducts from these glands at all to my own satisfaction, they are usually so very delicate that it is extremely difficult to detect them, and, although I thought that they followed the course which I now suppose to be correct, yet I could not feel any certainty. After trying numerous species I experimented on Lecosoma palmicinctum, in which I was pleased to find the ducts apparently more distinct ; they seem, as far as I can at present judge, to run in an almost straight course along the surface of the ventriculus, which they appear to enter just above the ceca (this is shown in plate I. fic. 4, n), where they are delineated as separated from the ventriculus by dissection. If this course of the duct be correct, the office of these glands is doubtless the secretion of some fluid useful in digestion. The point cannot yet be considered as decided, as the glands have some attachment to the outer wall of the body. I have since found that they are equally well seen in Notaspis lucorum. Probably, if Burmeister’s views were to be followed, these glands, from the place where their ducts seem to discharge, should be called pan- ereatic, but as the Oribatcde are vegetable feeders the function would not be analogous. The glands and ducts possibly form the homologues of one pair of the anterior caca of the ventriculus present in so many of the Arachnida. The dorsal part of the anterior portion of the ventriculus and of the whole of the ceca is usually covered with a thickish layer of brown follicular-looking cells, which sometimes entirely cover the dorsal surface of the ventriculus. JI cannot say that I have ever succeeded in detecting any ducts from this mass; they would doubtless be very fine, but I think that they are identical with those which many authors have considered as having a hepatic function. Thus Megnin, in his able treatises on the Gamasinz,* and on the Sarcoptide of mammals, says that he regards this brown granular substance as being analogous to that which coats the hepatic tubes of insects, and as being in fact the liver. A similar organization in many annelids was pointed out long since by Quatrefages,t who assigned it a similar office. Claparede speaks of the ventriculus, &c., and coating of cells as the “lebermagen”’ in the Hydrachnide, and that most careful anatomist, Cronberg, * “Mémoire sur Vorganisation et la distribution zoologique des acariéns de la famille des Gamasides,” Journ. Anat. et Phys. (Robin) 1876, p. 315. “ Mono- graphie de la tribu des Sarcoptides psorique,” Revue et Mag. de Zool., 1877, p. 157. + “ Mémoire sur quelques Planariées marines,” Ann. des Sci. Nat., 1840. 10 Transactions of the Society. expressly states his complete adherence to Claparéde’s opinion, extending it to Trombidium.* On the other hand Leuckart ¢ con- sidered that a similar tissue in the leach was not hepatic, and Ledig in his histology agreed in this with Leuckart, and the more recent investigations of Professor E. Ray Lankester ¢ would seem to point rather to a blood-elaborating function for this “botryoidal ” tissue. I have not been able to find any salivary glands nor any appendages to the hind- gut. The Reproductive System. This, next to the alimentary canal, is the largest and most important set of organs in the body; the general arrangement is very similar in the two sexes. When the notogastral shield has been removed, the genitalia may be seen lying at the sides of the canal, and in some instances, in the female, when the oviducts are distended with eggs, they seem to have usurped the place of almost all the other organs, and to have pushed them out of position. The Male Organs of Generation.—These consist of a large central testis, or more probably one on each side, coalescing in the median line by being imbedded in, and united by, a flat mass, which appears to perform the double office of increasing the quantity of the secretion and acting as a yesicula seminalis; two vasa deferentia, a ductus ejaculatorius, a penis with its accessory organs, and three pairs of copulative suckers. The testis, treating the whole as one organ, is very large, sometimes appearing to half fill the body and force its lobes up to the notogaster ; it usually extends the whole width of the body, and forms a saddle-shaped mass, which underlies the ventriculus in the centre, there constituting an almost flat layer of considerable thickness, deeply indented, both anteriorly and posteriorly, as though it were two paired organs which have met and united ; no sign of suture or demarcation is however visible there (plate II. fig. 1, a,b). In addition to this, each side has a tendency to be bilobed, and the anterior lobe, which is part of the flat mass, in some species, or at some periods, rises much nearer to the dorsal surface than the posterior one; the whole varies somewhat in form in different species, in Nothrus theleproctus the anterior lobes are large and rounded, in Oribata lapidaria they are smaller and squarer. Along each side of the flat part already described, and partly imbedded in it, but not reaching its anterior edge, runs a raised, rounded portion, which is oval in Nothrus theleproctus, but varies a little in different species. I have not ever succeeded in * “ Ueber den Bau von Zrombidium,” Bull. Soc. des Nat. de Moscou, 1879. + ‘Die Menschlichen Parasiten,’ vol. i. I Quart. Journ. Micr. Sci., 1880, p. 317. Observations on the Oribatide. By A. D. Michael. 11 finding any demarcation on the inner side, where they join, nor in removing one from the other without tearing both to pieces. The substance of both is white, soft, and glandular, but the rounded lobes stain more deeply with logwood, and then exhibit a mottled appearance; these lobes are probably the true testes, the flatter central portion would seem to be more or less hollow, and to serve as a vesicula seminalis, as well, probably, as an organ secreting some fluid to increase the quantity of the spermatic material; at all events the walls are very thick and glandular. The coalescing of the testes into an unpaired organ is of course common amongst the Arachnida, e.g. Phalangiwm; it also reminds one considerably of the arrangement in Homarus, and in Plewroma and other free-living Copepoda, &c., among the Crus- tacea, and in insects a very close approach is to be found among the Lepidoptera, as in Pontia brassice, &c.; but if the flatter central portion acts also as a vesicula seminalis this would apparently be a departure from the crustacean type. Nicolet draws the testis in Damzus geniculatus as being four oval, free bodies, on each side, not imbedded in any flat central portion. I am not able to account for this; certainly, when they are seen through the dorsal surface in transparent specimens, or seen after the noto- gastral shield has merely been removed, they might be mistaken. It may of course be suggested that the raised oval portion is the true testis, and that the central portion has some hepatic or other function, and not that of a vesicula seminalis ; but the absence (as far as I have been able to ascertain) of any ducts except the vasa deferentia, and the fact that they lead out of the flat portion, and the intimate way in which the whole is fused into one mass, would seem to negative such a view. The vasa deferentia are substantial tubes of moderate length, not longer as a rule than the testis itself; there is one on each side, springing from the anterior part of the flat portion, close to the raised oval (plate II. fig. 1, ¢), and passing downward, and slightly forward, until they join, and open into the ductus ejacula- torius ; they have a great resemblance to the paired vasa deferentia proceeding from the unpaired testis in the above-quoted case of Pontia brassice. As a rule they are retracted towards the surface of the testis. There is but little variety in these organs in the species which I have dissected. The ductus ejaculatorius.—The two vasa deferentia unite, as before stated, at their distal extremities, and are continued by an azygos duct considerably larger in diameter, but short; it is usually slightly invaginated, like the finger of a glove, and wrinkled longitudinally, so that it is capable of comparatively con- eo extension and contraction. It is shown in plate II. e.1,, d. 12 Transactions of the Society. The penis and accessory organs.—Taking Nothrus theleproctus as an example, the penis is a small chitinous organ, broader near the distal than the proximal end, but almost pointed at each, the distal end being bulbous (plate II. fig. 3), Near this end there is a chitinous process to which the retractor and extensor muscles are attached. This penis, when retracted, rests in, and is protected by, a second chitinous piece (plate II. fig. 2), which is concave, like half a tube (cut longitudinally) ; the distal end, however, is closed by a semicircular return, or turning-up, of the half-tube, so as to form a shallow pocket, in the edge of which is a notch, evidently as a guide to the penis when protruded. The walls of the proximal portion of the half-tube are turned outward and expanded, so as to form pyriform blades, doubtless with the object of affording a firmer attachment. The whole arrangement, when not in action, is retracted within a membranous sheath, which is retained in an open or distended condition by two curved chitinous pieces (plate II. fig. 2). The penis is, of course, in communication with the ductus ejaculatorius. This intromittent organ and its adjuncts bear a striking resemblance to those of Carabus glabratus, &c., in the Coleoptera: the drawing of the penis of one would almost serve for the other ; the mem- branous tube is Burmeister’s praeputium, and the chitinous pieces are his horny ridges, or bones, distending the same. The whole of the male organs above described, particularly the testis, vasa deferentia, &c., have a marked similarity to those described by A, Cronberg for Nesxa coccinea.* The copulative suckers, genital plates, &c., have already been well described by Nicolet. As far as I have been able to observe, the spermatozoa are not mobile or flagellate. I have succeeded in obtaining them from Dameus geniculatus by breaking up the testis, and also by pressing the part which appeared to me +o act as vesicula seminalis, almost immediately after death ; they are small, elliptical, highly refractive, bodies, about the 1-10,000th of an inch in the long axis; they are figured in plate II. fig. 4, highly magnified. They closely resemble, except as to size, the semen of Tegenaria guyonit Guerin, one of the spiders which were shown to me by I’. M. Campbell, of Hoddesdon ; these were non-flagellate, although some spiders appear to have flagellate semen. Blane figures the semen of Phalangiwm cornu- twm and other species as non-flagellate.+ The Female Organs of Generation —The general arrangement and position of these, as before stated, greatly resemble those of the male; it is, however, unnecessary to say that the differences are numerous and important. The organs consist of the ovary, * ‘On Lylais extendens,’ Moscow, 1878 (in Russian). + Bull. Soc. Vaud. de Sci. Nat., xvii. pl. 6, fig..23. Observations on the Oribatide. By A. D. Michael. 13 the paired oviducts, terminating in an unpaired vagina, the ovi- positor, and the copulative suckers and genital plates. The ovary, or ovaries, for it is doubtful if they should be treated as paired or azygos, consist of a large central sac or gland, which underlies the ventriculus, in much the same position as that occu- pied by the testis; this I take to be the true ovary, from the walls of which the eggs are differentiated ; it will be found fully developed, even when the creature has only lately emerged from the nymphal skin, and when there are not any eggs in the oviducts or other genital organs. At this period the walls of the ovary are cellular, the ova being more or less rudimentary (see plate II. fig. 5). At a later period, when the eggs have become developed, and when their formation and deposition is in active progress, the ovary may be seen to contain numerous eggs in a considerably more advanced state (plate II. figs. 6, 7). This central ovary appears to me possibly to consist of two paired organs, which have coalesced in the central line, much in the same manner as the testes. It ig true that the ovary of Oribata lapidaria (plate II. fig. 5, a), Oribata globula, &c., is an elliptical organ, giving little, if any, indication of a dual origin, particularly when immature, but in Cepheus tegeocranus (plate Il. fig. 6, a), in the mature ovary, there is a decided indication of a paired origin, there being a marked central constriction, and an approach to the outline of the coalesced testes. In Nothrus theleproctus, when the eggs are developed, the ovaries, or portions of an ovary, from the two sides have so slight an attach- ment to each other that they easily separate, and then appear as paired structures, one attached to each oviduct. The oveducts.—These, like the vasa deferentia, are two paired ducts, arising, one from near each end of the central ovary; they are long, membranous tubes, which, before the eggs have commenced to mature, appear empty; they are then usually corrugated and plicated organs, of about even dimensions throughout; they are shown in this condition at plate II. fig. 5, b, but it must be under- stood that this and all the other figures of ovaries are drawn from preparations dissected out and partly extended; when in sitw they are so much doubled backward and forward that a drawing of them in their actual position would not give much information. As the eges are formed, and after they have increased a little in size in the ovary, they pass into the oviducts, where the principal growth takes place. The oviducts seem to perform the function of a uterus, and the passage of the egg through them is consequently very slow; the eggs will sometimes be found small in the portion of the ovi- duct between the ovary and the globular enlargement mentioned below, and large in that between those parts and the vagina; at all other times, or in other species, the eggs all appear about the same size, i.e. usually all fully grown. The oviducts with the 14 Transactions of the Society. egos mature are shown at plate IT. figs. 6 and 7,b; their size then is uite disproportionate to that when the eggs are still in the ovary. The whole oviduct is greatly expanded, and each egg is lodged in a pocket, or chamber, formed by the distension of the elastic walls of the duct, and the flattening of the corrugations. This chamber usually follows the egg in its progress along the duct; in Damezus geniculatus, and probably in some other species, the earlier cham- bers do not appear to follow, or to subside after the passage of the egs, but persist to some extent ; this may be due to the egg remain- ing an unusual time there while acquiring its chitinous shell. In Oribata globula, Dameus geniculatus, and some other species, there is, on each side of the central ovary, and joined to it by a short portion of the oviduct, which is of equal length on each side, an almost globular extension of the oviduct, containing a globular body, which has the appearance of an ovum which has not yet assumed the oval form or the chitinous shell, and which almost entirely fills the chamber; these, like the central ovary, are developed when the creature first emerges from the nymphal skin, and while the other portions of the oviducts are unexpanded and empty. Both the central ovary, and certain large cells lying on or in the exterior walls of the two globular extensions, where the latter exist, stain deeply with logwood, &c., whereas the other portions of the oviduct scarcely take the stain at all. Whether these globular chambers be simply uterine, each containing an ovum, which here attains full size, or whether they are, or also function as, spermathecz, or glands secreting a vitelline substance, or one destined to form the egg-shell, is a question which I have not been able to decide to my own satisfaction ; some light may be thrown on the question of whether they function as spermathece when we know how copulation takes place, a matter which is not recorded, and which I have not succeeded in ascertaining ; but it is certain that in Damzus geniculatus, the egg of which has a very hard chitinous shell, and other species having this globular enlarge- ment, the eggs in the ovary, and between it and the globular body, are small, white, and soft, and show large clear nuclei and one or more round, distinct nucleoli, yelk-division not having more than commenced, even if it has commenced at all ; but that, immediately they have passed this point, they have attained their full size, and the shell has become harder and darker, and yelk-division has largely progressed. This would seem to indicate that the globular body is an ovum and the enlargement a special point in the duct functioning as a uterus in these species. The only difficulty of this view would seem to be that the globular expansions, presenting similar appearance, are present in specimens just emerged, which have not any other eggs in the duct. A portion of the ovary with the part of one oviduct up to and including the globular chamber, is shown filled with eggs at plate II. fig. 8. Observations on the Oribatide. By A. D. Michael. 15 The duct, even when full of eggs, continues to be plicated longitudinally, so that the eggs, when i situ, often appear to lie at the side of the body, one over the other in a bunch; this however is a deceptive appearance, they really follow each other in single file along the duct. The ova sometimes lie end to end, sometimes obliquely across the duct, sometimes almost side by side (through the stretching of the duct); the position of the eggs in the duct is very irregular, I have not ever seen them all following one another end to end at regular distances, and regularly increasing in size from the first to the last, as figured by Nicolet, although the end to end arrangement is not unusual in the species he figures. These oviducts are what Nicolet calls the ovaries, and what I term the ovipositor is named oviduct by him; I regret using the words in a different sense, but in the first instance it seems to me that his term is scarcely correct, although very natural, he not having observed the central ovary ; and in the latter case, although the organ is unquestionably an oviduct, as far as the derivation of the word goes, yet it appears convenient to distinguish it by a name different from the duct between the ovary and the vagina. The vagina, if this be a correct name for an organ which probably does not receive the male one, is a short but wide azygos duct, into which the oviducts lead ; it is manifestly the homologue of the ductus ejaculatorius, and is of similar consistency to the oviducts of which it forms the continuation. It appears to vary but little in the different species which I have investigated ; its office is to conduct the eggs from the oviducts to the commence- ment of the ovipositor. ‘The egg does not remain in the vagina for any length of time. The ovipositor, or external vagina of Burmeister, has been described by me in a former publication, and one form of it is well figured by Nicolet. I therefore shall not repeat it here; the same thing applies to the genital suckers and plates. Nicolet figures the female. reproductive organs of Damzus geniculatus more on the insect type than the crustacean, 1.e. without the central ovary above named, treating my oviduct as the ovary, and drawing it as diminishing to a point at each side, with the eggs regularly increasing in size from the distal point to the vagina. I have not found any specimen in this condition. It is necessary here to notice a remarkable error, as to the reproductive organs of Oribatidx, for which Dujardin is responsible,* but which has somehow retained a place in modern English works of authority.t The usually keen-sighted French naturalist started with the initial error that the Orzbatidz were viviparous : he, having this idea in his mind, did not consider that they could * “ Premier mémoire sur les Acariens,” Ann. des Sci. Nat., 3rd ser. iii. p. 5. + Rymer Jones’ ‘ Animal Kingdom,’ 4th ed. p. 309. 16 Transactions of the Society. have an ovipositor, and as he found the organ he took it to be the penis—a curious idea, for although that organ certainly attains a great length in some of the Acarina, e. g. Proctophylodes (Derma- leichus) glandarinus Koch, yet a male organ longer than the whole body, and thicker than the leg, would be an anomaly. Having settled this to his own satisfaction, Dujardin declared the opening below the hinder pair of plates to be the vulva, and concluded that the Oribatide were hermaphrodite; in this view Dujardin entirely forgot that the animals required an anus, and these errors still survive although Nicolet and Claparéde have exposed them, Respiratory Organs. Nicolet * describes the respiratory system of the Oribatide as consisting of two conspicuous stigmata, one on each side of the posterior portion of the cephalothorax, each stigma being funnel-shaped, and opening, by a minute circular aperture, into an air-sac placed transversely in the body and bent upon itself in order to reach the stigma, and of four larger and two smaller trachee on each side, the longer ones being distributed two to the dorsal and two to the ventral surface, and forming many convolutions, and the two smaller being allotted to the cephalo- thorax; and he states that this arrangement is general to all the Oribatide, and only varies in other families of Acarina, I confess that until I began actually to dissect out the respiratory organs I never for an instant doubted the entire correctness of this description, and for a considerable time after my dissections had commenced, I thought that I must have missed the arrangement described by the French naturalist in consequence of the difficulty of the investigation. I found, however, that I could not, in any instance, trace the traches up to the position described, nor could I find any air-sac in this place from which they originated, although I found a sac or tube, apparently glandular, not far off, but with liquid contents instead of air and not connected with the trachese. In the course of this investigation I have dissected over fifty specimens belonging to numerous species: I find, with sincere regret, that although many parts of Nicolet’s descriptions are correct, yet I am not able to agree with him in other important particulars. The breathing organs in the adults are usually, as he correctly says, trachez (I omit the air-sac question at present) ; these trachee are very long, and so delicate that the slightest attempt to move or separate them, even with the finest badger-hair, usually breaks them, and as they are, as Nicolet says, considerably convoluted, and are interlaced amongst the other organs, I have not found it possible to ascertain with certainty exactly how many there are. * Loe. cit., p. 410. Observations on the Oribatide. By A. D. Michael. 17 I incline to think that it varies. J have also found that instead of being similar in all species the system differs materially. To commence with the more ordinary arrangement, such as that found in Oribata globula, a very good species for seeing the tracheee, Damzus geniculatus, &c. The main trachez are simple tubes, never anastomosing, and usually without any branches or dichotomous or other furcations or divisions ; indeed I doubt if such ever exist. These tubes are much convoluted, or serpentined, and interlaced amongst the other organs. One large trachea on each side, which I will call the great dorsal, winds above the alimentary canal, very close to the notogaster, until near the posterior margin, when it takes a deeper course, following the alimentary canal, and becomes very difficult to trace. Another large trachea on each side, which I will call the great ventral, passes in a serpentine line ‘along the ventral surface and is in connection with the sexual organs, winding about the oviduct and ovary in the female. Hither one or two large tracheze on each side proceed more along the lateral edges of the abdomen, between the two before described ; there are also two or more shorter and finer unbranched tracheze allotted to the cephalothorax on each side, one pair being distributed to the great muscles of the mandibles. The trachez are of almost even diameter throughout the principal part of their length, towards their ends they usually diminish and end in a point ; this is not, however, invariable, as the large trachezx, on the contrary, sometimes enlarge at their distal ends so as to form small bulbs. The large tracheze above described approach very near to each other at their origin, and if one does not actually follow them to their commencement (a matter of no slight difficulty), but is satisfied with their appearance after the removal of the notogaster, they unquestionably do look as if they were proceeding to the old so-called stigma (my pseudo-stigma) which seems to be the natural place for them to go to; if, however, the adipose tissue and muscle be removed, and the tracheze followed to their origin, it will be found that they turn away from the pseudo-stigma, and end separately in the acetabula of the legs. The trachez are often enlarged at the commencement so as to form a small air-sac, which either wraps round or is attached to the inner side of the acetabulum : this is seen in plate I. fig. 5 and plate I. fig. 9. One main trachea only usually proceeds from the acetabulum of each leg, but in some cases two proceed from that of the second leg, and more than one of the small cephalothoracic trachez from that of the first leg. In these cases they often join before reaching the stigma and form a very short joint trunk (plate I. fig. 6). In consequence of the interlacing of the trachee among the organs it is far from easy to ascertain which trachea proceeds from each acetabulum, but it appears to me, as well as I could trace Ser. 2.—Vot, III. Cc 18 Transactions of the Society. them, that the great ventral trachea proceeds from the acetabulum of the fourth leg, the great dorsal from that of the third leg, the lateral trachea or tracheze, which wind among the organs and cross right over the body, from the acetabulum of the second leg and the small cephalothoracic trachez from that of the first. I think it possible that the two small trachee belonging to the cephalothoracic system find their stigmatic opening at the base of the maxille. I should be extremely doubtful about this last point were I speaking only of the species whose trachez are described above, as in them these trachez, wherever they open, are extremely fine and delicate; but in Nothrus theleproctus, &c., referred to below, the air-vessels in this situation are more powerful, and seem as though they were proceeding to the mouth, and it must be remembered that this is the position of the principal stigma, or stigmata, in Cheyletus,* Trombidiwm,} Myobia,t the Hydrach- mdz, &ec. In other members of the family, such as Nothrus theleproctus, the respiratory system above described is greatly modified: the origins of the trachee are placed in the same situations as in the species above described, but the nature of the air-vessels is very different; we no longer have long winding trachee of small diameter and very delicate walis, we have instead much shorter organs, thicker and less regular in form, and of a stouter and different texture, by which they may be easily recognized when the body is opened, as they have a thick, silvery appearance not easy to describe. Under a low amplification they assume that slightly iridescent appearance characteristic of a lined object under a power insufficient to resolve it; using a higher power regular cross lines are strongly developed, and a still greater amplification will show an object thickly and regularly covered with small circular bosses which will remind the observer of such a diatom as Plewrosigma formosum: this may, however, possibly be a deceptive appearance. The trachez or air-vessels proceeding from the acetabula in the species now being described, are very much shorter and thicker than in the form before referred to, and are not convoluted or interlaced between the organs to the extent which we find in the longer and finer trachez of Oribata, &c. ; at their extremity furthest from the stigma (the blind end) they are usually suddenly diminished in diameter and carried on for a very short distance in a blunt point. In this form the air-vessels in the cephalothorax, which may * Fumose et Robin, ‘Mémoire anatomijue et zoologique sur les acariens des genres Cheyletus, &e.,” Journ. Anat. et Phys, (Robin) 1867, p. 563. + Pagenstecher, ‘ Beitrage zur Anatomie der Milben,’ Leipzig, 1860, Heft 1, 9. ‘ + Claparede, “ Studien an Acariden,” Zeitschr, f. Wiss. Zool., 1868, pl. 37. Observations on the Oribatide. By A.D. Michael. 19 possibly arise from oral stigmata, assume greater importance and become some of the largest; a short wide trunk leads into a chamber, from which proceed two cecal prolongations of unequal length (plate I. fig. 7); these share with the other trachee the characteristic of being short, and of the structure described above. It is very interesting to find this slightly developed and almost rudimentary condition of the trachez in the genus Nothrus, when we remember that the nymphs and larve all through the family usually have the trachee in a rudimentary state, and that in this genus the want of hard chitinization in the integument of the adults, their great resemblance to the nymphs, their carrying the cast skins in some species, and other indications, seem to point to creatures where the adult shows less progress from the nymphal stage than in other genera. In the genus Hoplophora I have hitherto failed to discover any tracheze whatever; Claparede was greatly surprised at the same thing,* he found, beneath Nicolet’s stigma, which he calls peritrema, three very minute sacs filled with air, which he says are not longer than the width of the stigma, and which, from his drawing, cannot be above the 1-25Uth of a millimetre in length (his entire creature being over a millimetre); he considers these to be the entire respiratory arrangement of the creature, and to be modified trachex, equivalent to the so-called lungs of spiders, scorpions, &c. Although he did not find any leaf-like arrangement within the sacs, or any blood-vascular vessels in connection with them, it must, however, be remembered that Claparéde was doubtless relying upon the statement of Nicolet, whose book he quotes, that the trachez in other species arose from this so-called stigma. Claparéde expresses his astonishment at the extremely rudi- mentary condition of these respiratory organs, and he well might do so; one naturally is diffident of questioning a conclusion on this subject arrived at by a man so extremely well acquainted with spiders’ lungs as Claparede, but I cannot think that a sufficient respiratory system is shown here; it seems to me far more likely that these minute sacs are connected with the functions of hearing or smell performed by these pseudo-stigmata as suggested by me in an earlier number of this Journal, and it seems to me that there are other means to be found by which aeration could take place in Hoplophora. We know that in many soft-skinned acari, as Tyro- glyphus, Sarcoptes, Dermaleichus, &c., respiration is performed by the general body-surface without special organs ; now in Hoplophora, in consequence of the movable ventral plate, so different to that of other Oribatide, its opening and closing must have a bellows-like action, and great quantities of air must be drawn inside the carapace * «Studien an Acariden,” Zeitschr. f. Wiss. Zool., 1868, p, 512. c 2 20 Transactions of the Soctety. and over the delicate lining membranes through which aeration of the blood may well take place. Before leaving the subject of the respiratory organs I will say a word more as to my not adopting the view held by Nicolet and Claparéde, and generally received, that the two organs which look like stigmata on the cephalothorax really are so. One hesitates greatly to attack a conclusion supported by so much authority, but Nicolet is really the only observer who has ever investigated beyond the external appearance; Claparéde only dissected Hoplo- phora, and there he did not find anything in connection with the so-called stigmata except the minute air-sacs referred to above. The matter is one of fact; of the trachez large enough to be traced I have not ever succeeded in finding one attached to the so-called stigma, or proceeding from any air-sac attached to it, and I have found them originating in other places, as detailed above. Again, the pseudo-stigmata are quite as highly developed in the larvee and nymphs as in the adults, although the tracheal system is quite rudimentary in the immature forms as far as the observations of other arachnologists and of myself extend, a circumstance (as to the absence of tracheze in immature forms) also observed by Pagen- stecher in Ixodes and Trombidiwm, and by Kramer in Gamasus, Tarsonemus, &c.; and again the extremely small internal opening of the pseudo-stigmata, which is almost or quite filled by the peduncle of the so-called protecting hair (my pseudo-stigmatic organ), is against the hypothesis of their being true stigmata. For what it is worth, it may also be mentioned that in Pygmephorus spinosus, a parasite of the mole, which possesses organs much resembling the pseudo-stigmata of the Orzbatidx, Dr. Kramer, its discoverer, could not trace any trachez to these organs; * although doubtless the weight of this is lessened by the fact that, in con- sequence of want of specimens for investigation, he was not able to trace the tracheze to any stigma. The Super-coval Glands. I have said above that Nicolet describes an air-sac which I can- not find, but that I do find a sac, which I believe to be glandular, not far from Nicolet’s position, although not attached at the point he names. ‘This sac I propose to call the super-coxal gland, and I have very little doubt, from Nicolet’s drawing, that this is the organ he saw and supposed to be connected with what he and others imagined to be the stigma. When the dorsal exo-skeleton of the cephalothorax, and the adipose tissue which underlies it, has been removed, what appears to be the enlarged, blind end of a fine * “Zwei Parasitische Milben des Maulwurfs,” Archiv f. Naturgesch., 48rd year, Bd. 1, p. 257. Observations on the Oribatide. By A. D. Michael. 21 colourless sac, may be seen on each side of the body, the seemingly blind end being nearest to the eye; the sac descending obliquely downward and slightly forward, and being attached close to the acetabulum of the coxa of the second leg; a closer examination shows that this is not the only attachment, but that the lower end is apparently bifurcated, and that the second branch is attached much nearer to the centre of the body, and higher in level than the coxal branch. On dissecting out this sac, and carefully ex- tending it, a matter by no means easy, it will be found that what seemed to be the blind end was not the end at all, but that the whole organ is an elongated, sausage-shaped sac, bent upon itself in the middle and taking a single turn, so that the two halves cross, but for some distance the two limbs of the horseshoe (if I may call them so) lie over each other, or are so closely pressed against one another as to appear one; it is only toward the ends that they stand free from each other when in situ. The general position of the organ in the body is shown at plate I. fig. 8; and the organ unfolded and showing so much of its minuter structure as I am acquainted with at plate I. fig. 9. The walls of the sac are colour- less but highly granular, and apparently of considerable thickness, and, it appears to me, decidedly glandular. Within the sac, i.e. either on its inside surface or in the substance of the wall, and near to the centre (long axis) of the sac, is a double row of highly re- fractive points, arranged at regular distances, those of the two rows not being opposite, but alternate. A fine distinct double line may be seen uniting these alternate points so as to form a double zig- zag line all along the organ, the refracting points being slight prolongations of the zigzags. Three possible explanations of this structure would seem to offer themselves. 1. That the double lines are tubules as in the nephridia of Vermes. 2. That the space between the fine lines is really the zigzag lumen of the sac, possibly running between cells projecting alternately from the opposite walls, and having a cuticularization at the refractive points. 3. That the whole (zigzag and points) is a cuticular strengthening on the interior wall of the sac, the cuticularization being greatest at the refractive points which may be intercellular. - Connected with this tube isa globular body, which has thick but less granular walls, and which is probably hollow; both the gland and this body, when pressed, discharge liquid. There is not any sign of air in either. What is the office of this organ? I cannot, of course, pretend to do much more than guess, but if a suggestion be allowable, I would point to the nephridia (segmental organs) in Vermes, and the green gland in Astacus and other crustacea, and the coxal glands in Scorpio and Limulus, as those where the analogy may be sought. ‘The resemblance to the former, in particular, is very 22 Transactions of the Society. considerable in the general form of the organ, and toa lesser extent in the minuter structure ; if the double lines be tubules they would be analogous to those in the nephridia.* The sac above described (super-coxal gland) would correspond with the gland in the neph- ridium, and the globular body with the vesicle. The position would seem to correspond fairly with that of the green gland and the coxal glands, in the former of which Will and Gorup-Besanez say that they found guanin,t+ and Huxley says that if this be so there can be little doubt that it represents the kidney, and its secretions the urinary fluid ;{ while Ray Lankester is inclined to look on the latter as homologous with the nephridia.§ I cannot say that I have succeeded in finding any actual opening of the super-coxal gland to the exterior, but the extremely small size of the creatures and of the gland, and the position of the latter, make it very difficult, and indeed Professor Lankester does not seem as yet to have been more successful in this particular respect with the larger forms which he has been dealing with. In Hoplophora magna, about in a similar place to the above- named super-coxal glands (as far as the peculiar form of Hoplophora will allow), I find, on each side of the body, a pyriform sac, haying the smaller end toward the legs, and the larger, blind end, toward the centre of the body; this sac has walls less finely granular than the glands in Leiosoma, &c., but very glandular; I have not found in it either the refractive points or the zigzag markings ; it is not bent nor doubled on itself nor twisted ; there is a’ globular vesicle, darker in colour than the sac, on each side of it. These organs require further investigation, but it would appear probable that they are the homologues of the super-coxal gland and vesicle, although presenting considerable differences. The Ezxo-skeleton. The only two points relative to the exo-skeleton which I intend to refer to are:—-1. The tectum; 2. The mandible of the species which Nicolet calls Lecosoma microcephala. The tectum is a part which owes its name to Nicolet; he alone has pointed out the existence of such an organ; as far as I know it does not exist in any other creatures, and it will be seen from the following remarks, that, in my opinion, it does not exist at all. Nicolet’s statement, when treating of the cephalothorax, is as follows :—“In a large number of individuals, forming the first division of the Oribatide, the upper part of the cephalothorax is * See A. G. Bourne, “ On the structure of the Nephridia of the Medicinal Leech,” Quart. Journ. Mier. Sci., 1880, pp. 283-302. + Gelehrte Anzeigen d. K. Baierischen Akad., No. 233, 1848. { ‘The Crayfish,’ 1880, p. 83. § Proc. Roy. Soc., xxxiv. (1882) pp. 95-101. Observations on the Oribatide. By A. D. Michael. 23 dominated, and sometimes entirely hidden, by a lamellar and tectiform expansion of its base, which advances forward, following its declivity (that of the rostrum), and assuming a form more or less triangular, according as the former is more or less angular, the sides of which expansion are raised oblique projections, often pro- longed beyond the front (of the expansion), and always terminated by two setiform hairs. This apparatus, of the functions of which J am ignorant, but which I consider as a protecting organ, and to which I have given the name of tectum, extends from the base of one stigma to that of the others. The lower face of this organ, where it is opposed to the upper surface of the cephalothorax, is not always free in all species; there even exist some in which it is adherent all its length, and then the tectum is only distinguished by its lateral wings, which in that case are usually more developed. In other species this same tectum presents itself as two sub-parallel blades, united by their inner edges, truncated.and rounded anteriorly, and through which the body of the cephalothorax may be seen ; in this last case the tectum has not any lateral expansions. If I notice these different modifications of the tectum it is because this eminently variable appendage is the best specific distinction that the Oribatide of the first division present.” Nicolet founds upon variations of the tectum, not only specific ° distinctions, but even those of sub-families. He describes it in several places, and evidently regards it as a chitinous shelf standing free in the air in many species, except that its basal edge is attached to the hinder part of the dorsal surface of the cephalothorax. This shelf, he says, has turned-up lateral edges in most species; these he sometimes calls the raised borders and sometimes the lateral wings of the tectum; for distinctness I shall give them a name, and I speak of them as the lamelle. I have always had great difficulty in distinguishing the species that Nicolet said had free tecta attached by their base only from those which he said had tecta attached by their whole under surfaces by this means of differentiation, but I presumed that Nicolet had satisfied himself that there was such a thing as a detached tectum, and it never struck me to doubt the existence of such an organ until I came to dissect for the purposes of the Ray book; had I doubted it, and trusted to inspection of the living creature, or of dead or mounted examples, I should probably have still considered Nicolet to be right, for certainly in such species as Cepheus tegeo- cranus (vulgaris), which is the very type of Nicolet’s free tecta, it looks so very like what he described, that I not only should have been, but was, deceived; when, however, I came to dissect the organ away from the cephalothorax in this type species, I found, to my amazement, that there was not anything to come. I then passed a hair under the long projecting ends of the lamella, and 24 Transactions of the Society. found that there was not any difficulty in carrying it back as far as the point where the tectum was supposed to commence, but there it stopped, and that nothing would get it any further, whereas it ought to have passed equally easily into the supposed space between the tectum and the dorsum of the cephalothorax (or vertex as Nicolet calls it). It then struck me that amongst all the very large number of specimens of Oribatide which I had examined I had not ever seen one where any dirt had got into this space, although it gets into every other place where there is a small hole or depression, and this would be a receptacle just fitted for it; but 1 thought that possibly a thin liquid, such as alcohol, or even water, might run in where a hair or solid matter would not pass. I accordingly tried, but could not get any to run under the supposed tectum; by these methods, but more especially by careful and frequently repeated dissection of various species, I at last became convinced that the tectum of Nicolet did not exist, and that the appearance of it in Cepheus, &c., was an optical delusion. In Oribata punctata, &c., the greatly enlarged and horizontal lamellee somewhat simulate a tectum ; this form is Nicolet’s sub-parallel blades. ; How does the appearance of Cepheus, &c., arise? It seems to me that the explanation is as follows :—The lamelle are real and exist- ing organs, easily seen by even the most superficial observer, and quite easy to get away, by cutting or breaking, but instead of being the upturned edges of a special, detached, horizontal, chitinous organ, they are simply outfoldings of the cuticle of the cephalothorax itself, just as the apodemata which serve as points of attachment for so many of the muscles, are infoldings of the same cuticle; in this manner it is natural that the base of each lamella should be thicker than its summit (or edge), which indeed does not include the true cuticle at all, but only the chitinous secretion from it, and the lamella, being a fold of the cuticle, does not spring sharply at right-angles from the surface of the cephalothorax, but rises ma curve, produced, so to speak, by the dragging up of the cuticle from each side; thus each lamella has a more or less triangular transverse section, the sides being curved and giving considerable extension to the base, particularly on the inner side. The dorsal surface of the cephalothorax, from which these lamelle spring, is convex, and the broad inner base of the lamella filling up the depression caused by the lower part of the convexity, causes the whole space within the lamelle to appear, and really to be, higher in level than the other parts outside the lamella. Again, the ends of the lamelle usually rise forming projections, sometimes very short, but often of considerable length, which stand quite free. At the point where the lamella cease to be attached by their lower edges, and rise to form the free projections, the two lamella are Observations on the Oribatide. By A. D. Michael. 25 most frequently joined by a transverse ridge of the same nature, which, in some species, as Orzbata setosa,'O. orbicularis, &c., is large and conspicuous, almost as much soas the lamellee themselves ; in most species, however, the cross ridge is much smaller, often a mere line, and it has then the appearance of being the anterior edge of the supposed tectum; as it does not rise sharply on its posterior edge, but slopes up gradually, it would seem to be a natural result of the folding of the cuticle to form the projecting end of the lamella. The last point I shall refer to is the exceptional mandible of one single species. The ordinary mandible of the family is a chelate mandible which, in all genera, except Pelops and the instance I am about to mention, is broadest in the middle and is terminated by a powerful chela (plate I. fig. 10). In Pelops there is marked difference in the shape of the mandible (plate I. fig. 11): the base is broad, almost quadrangular, then the organ suddenly narrows and is continued as a long thin rod, terminated by a very fine chela; this doubtless fits it for exploring small holes. In every recorded instance the mandible is chelate, and this is given as a leading characteristic of the family. One of Nicolet’s species is Lecosoma microcephala; in external appearance it is but slightly distinguished from other species of the same genus. It is rare, and I had only two or three specimens; it is my habit to draw the mandible, but this necessitates breaking up the creature, and as they usually vary but little I did not like destroying a specimen ; from what I could see, however, I suspected that there was something unusual in the trophi, and I sacrificed one of the three; to my astonishment I found a mandible (plate I. figs. 12, 13, 14), totally different from that of all other Orzbatidee which I know of ; having somewhat the form of the Pelops mandible, but longer in the shaft (or thin portion), and curved instead of straight, but not chelate at all, on the contrary, devoid of any moyable joint, and regularly serrated along the distal portion for a considerable length so as to serve as a sawing instead of a seizing or tearing organ. it seems to me that with this essential variation it is not possible to leave it in the genus Letosoma, and I propose to create a genus to be called Serrarius for its reception. Finally, I wish to express my thanks to Mr. Charles Stewart, of St. Thomas’ Hospital, both for his encouragement to persevere in what I feared might prove to be investigations too difficult for me, and for his able opinions as to the results I had obtained; and also to Mr. E. Bostock, of Stone, and Mr. C. F. George, of Kirton Lindsey, for supplies of living specimens which enabled me to continue the research in London. 26 Transactions of the Society. II.—On a Minute Form of Parasitical Protophyte. By G. F. Dowpeswett, M.A., F.R.MS. (Read 14th December, 1882.) Our knowledge of the minute forms of proto-organisms—pathogenic Bacteria, as they are frequently termed—which in some cases have been shown to be the cause, constituting the contagium, of infective diseases, has been greatly extended by recent advances in optical science, together with improved methods of preparation, and their presence has now been demonstrated where previously it was but suspected. Where recognized they were mentioned under general terms, without it being practicable to describe the characters which distinguished one form or species from another ; whereas now we are often able closely to examine and measure some of the forms so as readily to discriminate and define them. There are others, however, so minute as to tax our best csources : such is the microphyte now offered to notice. The preparation in which it is shown is a section of the lung of a mouse infected with a form of septicemia, in which this organism appears to constitute the contagium. From a micro- scopical point of view a principal feature of interest here hes in the circumstance of its ultra-minute size, being, I believe, the most minute independent organism yet described. The specific characters of this disease have been described by Dr. Koch in Germany * and by myself in this country. It has not been observed to occur spontaneously, though there is every probability that it does so, inasmuch as the contagium in this case unquestionably originates in contamination from the atmosphere, and it is a significant fact that specific infection, or in other words, the occurrence of this organism in the putrid blood used for inoculation, is far more uncertain and rare in the winter months than in the summer and autumn. This is accounted for by the fact that the lower fungi or their germs are far more abundant in the air in summer than in winter. In the section of lung shown occurs a large vein, in longi- tudinal section, in which amongst the red blood-corpuscles,t which are well preserved by absolute alcohol, there are seen several deeply stained round cells; these are the white corpuscles of the blood, somewhat swollen, and filled in varying numbers with the minute parasite here in question—in some, where not too crowded, they can be distinctly resolved ; on the inner walls of the vessel too * Untersuch. iib. d. AXtiol. d. Wundinfections-krankheiten. Leipzig, 1878. + Quart. Journ. Mier. Sci., xxii. (1882) p. 60. + Their diameter is about 1-4000th in., those of man being 1-3200th in. On a Parasitical Protophyte. By G. F. Dowdeswell. 27 they occur in vast numbers, and may also be recognized in most of the smaller blood-vessels or capillaries. The organism itself is a form of bacillus, the individual cells of which, allowing for foreshorten- ing, are almost exactly 1 micromillimetre (0°001 mm., 1-25,000th inch) in length; that is, just the breadth of some common forms of similar organisms, septic and pathogenic Bacteria, as e. g. the hay- bacillus—B. subtilis of Cohn. Their breadth, by estimation, is certainly less than a fourth of the length, i.e. less than 1-100,000th of aninch. To examine and measure these accurately it is neces- sary that the blood containing them should be spread in a very thin layer on the cover-glass, dried and stained. In the tissues, thin and completely decolorized as the section here is, they cannot be sufficiently clearly seen for individual examination. Judging from the relative position and appearance of the cells, it pro- bably possesses a flagellum ; * and no doubt, as other bacilli do, it must form spores, though not perhaps in the tissues of the living animal, where its usual method of multiplication is evidently by fission. ‘These spores would be mere points under the Microscope, circular bodies of only about the fourth or fifth of a micro- millimetre, i. e. less than 1-100,000th of an inch in diameter. The number in which these organisms may exist in the blood of an infected animal is incalculable; it may be even infinitely greater than in the case of Davaine’s Septiceemia in the rabbit, where, as stated at a previous meeting of this Society,t I found that in some cases one drop of infected blood contained upwards of 3000 millions of them. In this case the blood is as infallibly infective as in the other, in the smallest quantities in which it can be taken on the point of ascalpel or a needle. I have not, however, been able to test its infectivity quantitatively, as in the former case, on account of the small size of the animal here, and the blood being invariably much coagulated upon death. It is a remarkable circum- stance and one, I believe, peculiar to this disease, that the blood of an infected animal during life and within 18 hours, or even less, after inoculation, and previous to the occurrence of any apparent symptoms of disturbance, becomes itself infective, in as small quantities, and in all respects with similar results, as with inocula- tion by the blood of a dead animal. * The flagella, if they exist, are probably mere filaments of homogeneous substance: very different from complex independent cells. Many microscopical objects are not distinguishable with our present means unless stained, either on account of their being of the same refractive index as the tissues (as in the case of the nuclei of cells), or on account of their minute size (as in the case of this microphyte), and the possible occurrence of others yet unobserved and perhaps unsuspected is suggested by Koch’s remarkable discovery of the bacillus of tubercle, which, owing to the chemical reaction of its cell-wall, is not affected by the dyes which were previously supposed to stain all species of the Schizophytes. + See this Journal, ii. (1882) p. 310. 28 Transactions of the Society. A question often occurs as to the danger to man of infection with these highly virulent septic diseases. It may be said that in general they are only infective amongst animals nearly related generically. That Davaine’s septicemia in the rabbit is not infective to man, has been proved, accidentally of course ; experi- mentally, too, it has been shown that it is not communicable to cattle, horses, or sheep. It is certainly not infective to dogs or cats, though readily so to guinea-pigs and mice. With anthrax, however, it is otherwise; that is virulently infective to man, amongst whom it is known in this country as wool-sorters’ disease ; cattle and agricultural stock of all kinds are liable to it, as are most rodents ; also dogs and cats with difficulty ; and amphibia and birds under certain artificial conditions, as has lately been shown. Mouse septicaemia, I have found, though others have asserted differently, not to be infective to other animals, either rodents or others. All the circumstances of this affection, to some of the most prominent of which I have here called attention, are easily accounted for on the theory of the microparasitical origin of the disease, and as it appears to me on no other. As an objection to this view it has been asserted that specific pathogenic micro- organisms are normally present in the blood and tissues of healthy animals, and that they merely develope and multiply in the patho- logical or debilitated condition consequentupon inoculation with toxical matter. I have found this statement to be erroneous; the fact is that septic or putrefactive bacteria, as distinguished from patho- genic, are apparently normally present in the organs and tissues, which they invade, and develope in the blood, after death ; to distin- guish between these species is the province of microscopical obser- yation. To the neglect and inaccuracy of this, which in some cases is very remarkable, is due much of the obscurity which still involves this subject, and has prevented the recognition of the relations of these micro-organisms. On the discrimination of their distinctive morphological characters depend some of the questions which are of fundamental importance in bacterial physiology or, as the developing science has been more comprehensively termed, Schizomycology. In this view those engaged in investigating the subject look with warm interest to any improvement in the optical powers of the Microscope.* * The description of this organism was illustrated by drawings showing the relative size and form of some different species of pathogenic and septic bacteria, under an amplification of 2800. The large forms were drawn by the camera lucida and a 1-16th water-immersion objective of Messrs. Powell and Lealand, with an eye-piece of about 3-4ths in. focal length used with the micrometer. The objective with which the preparation was shown was a 1-20th homo- gencous immersion of Powell and Lealand (1°38 N.A.) constructed specially for the examination of these proto-organisms, for which it is most admirably suited and invaluable. (a ae Ill.—On the use of Incandescence Lamps as Accessories to the Microscope. By C. H. Sruarn, F.R.MLS. (Read 10th January, 1883.) As for the last ten years I have not followed the progress of micro- scopical science, I cannot but feel that in venturing now to speak on microscopical subjects, I am in a similar position to that of a colonist who, on returning to his native land, finds that the world has moved on and left him far behind. Yet it is my hope that from those fields of research in which my thoughts have of late years been straying, and in which my former microscopical pursuits have been discontinued, I may have been able to glean some infor- mation which, though not primarily connected with microscopical science, may, in its practical application, prove of some utility to microscopists. When, in 1871, I first commenced the study of the physics of high vacua, it was with the object of investigating the law governing the arrangement of the lines in the spectra of rarefied gases; but after my meeting with Mr. J. W. Swan, in 1877, I entered with him upon an investigation, having for its object the discovery of the conditions under which thin carbon conductors could be rendered permanent when made incandescent by an electric current in the most perfect attainable vacuum. With what success that investigation was attended, my colleague has already described in his lectures and pamphlets; and I presume that there are few here present to whom its practical results in the form of incandescence lamps are not by this time familiar. From a scientific investigation, the matter has now grown into a great commercial enterprise, and ere many months are over, there seems a probability that in many places gas will be entirely superseded by elecirical illumination. When this happy time arrives, the application of the incandescence electric lamp to the purposes of microscopical illumination will certainly become uni- versal, as it will then be not only the purest and most satisfactory light, but will be at the same time the most convenient. I hope, however, to show that microscopists need not wait for the realization of the hopes of the shareholders in electric companies, and the fears of those interested in gas companies, but may at once discard their troublesome oil or gas lamps, with many of their acces- sories, and proceed at once to avail themselves of the advantages of electric illumination. I am aware that Dr. Van Heurck, of Antwerp, has anticipated me in the application of our lamps to the Microscope; but, as those employed by him were of comparatively * 9 30 Transactions of the Society. large size,* the battery power necessary to render them incandescent would, till electricity is supplied from a central station, constitute a bar to their general use. There can be no advantage in using a large light at a distance from the object, when a small one near to it will give as good, or better, results, and will at the same time require the expendi- ture of so little electrical energy, that the trouble attendant on the use of the battery is almost inappreciable; and in this way ate can be made a permanent attachment to the Microscope itself. The lamps I have constructed for the purpose are shown full BREE raitiae size in figs. 1 and 2, and dn situ on the Micro- es _ scope in fig. 3 at A Band C. The length of 7-~. the incandescent filament is 1-10th of an inch, its diameter 1-166th of an inch, and its superficial area about 1-555th of a square inch. Two Bunsen or four Leclanché cells are sufficient to render them fully incandescent ; but for general purposes it will be best to use an additional cell, regulating the intensity of the light by means of the adjustable resistance coil D interposed in the battery cireuit and attached to the base of the Microscope. As the duration of the lamps is in an inverse ratio to the temperature at which they are maintained, it is desirable that the most intense light that the lamp will give should only be employed for a very short time when a special effect is required; such, for instance, as for purposes of micro-photography. If the lamp is at other times used no brighter than is necessary to obtain a white light, and the current turned off when observation is not going on, the lamps will last a very long time, as experience has shown that a life of more than 2000 hours of continuous and brilliant incan- descence is frequently exceeded by Swan lamps. It is possible to obtain a light of 2} candles from the tiny surface just mentioned, with an electro-motive force of 34 volts, and a current of 1} amperes. It would, however, at a safe temperature, give a light equal to one candle. , It will be found the most convenient plan to keep more than one, say three, of these lamps on the instrument, so that by merely turning a switch the position of the light may be varied. (1) For the illumination of opaque objects the lamp A (fig. 3) is attached by a jointed arm E, to an insulated collar a, which screws on above the objective. The source of light can then be rotated around the object while under examination, so that delicate surface markings can be readily brought out. * Since the above was written Dr. Van Heurck has informed me that he has used lamps requiring an electro-motive force of not more than 7 volts. On the use of Incandescence Lamps, &c. By C. H. Stearn. 31 (2) On moving the switch b from the central position to the right, contact is made with another stud, and the current passes to a second lamp B, mounted on a platform fitting into the substage, Fic. 3. and capable of rotation and lateral adjustment, so that direct or oblique illumination at any angle may be obtained. 32 | Transactions of the Society. As the source of light is almost a point, and the lamp can be brought very nearly into contact with the slide, a greater degree of obliquity of the illuminating rays can thus be obtained than by almost any other method, and hence black-ground illumination is shown with great beauty, and many of the diatoms display diffrac- tion colours with unusual splendour. The resolution of test objects becomes very much simplified, as most of them can be resolved by the lamp alone, without any accessory apparatus. (3) For use with the polariscope, a third lamp C, of slightly larger size, is placed in the position of the usual mirror. It is put in action by moving the switch to the left, so as to make contact with the third stud. This lamp requires an additional cell so as to develope a light of about four candles. As the sockets of the lamps are all made to a standard size, it is easy if more light be required than is given by the smaller lamp, to transpose the larger one to either of the other positions and use the full strength of the battery. If it is found desirable with the lower powers to give parallelism or convergence to the rays, a very small lens can be mounted in front of the lamp. If a more simple mounting is desired, the forms shown in figs. 4, 5, and 6 may be adopted; and the lamp can be thus placed in any position above or below the stage. If it is required to maintain the lamps for several hours at full incandescence, the most satisfactory battery to use would undoubtedly be a Bunsen or Grove. If, however, the switch is turned off whenever an observation is completed, a recent modifi- cation of the Leclanché answers admirably ; for if exhausted through polarization it recovers itself when left for a short time, and will, when once filled, keep in good order for several months. It is best to use five of these modified Leclanché cells, controlling the strength of the current by means of the resistance, and diminishing it as the potential of the battery falls. For all ordinary work these Leclanché cells will be found to meet all the requirements of the microscopist. ‘The Swan-Sellon, or Faure accumulator will also be found convenient, but these are at present rather expensive luxuries; and though they last for a considerable time when charged, the trouble of charging at intervals would probably counterbalance the advantages gained in other ways. I have been able to light these lamps satisfactorily with a small dynamo, about five inches in length; and if it be possible to obtain a spring which can be wound up by hand, and will drive it for about half an hour without occupying too great a space, this may probably be a very convenient method of obtaining the current when required. When, however, we consider that to obtain the amount of electrical energy represented by the product of 34 volts and 14 amperes, weshould haye to expend about 4 or 5 foot-lbs. of mechanical On the use of Incandescence Lamps, &c. By C. H. Stearn. 33 energy per second, the probability seems rather remote; and both for convenience and economy, the modified Leclanché cells carry off the palm at present, so far as microscopical illumination is concerned. Fig. 4. Zao — i iit a ————<——— ———— {To CC _—_—_————_— Ser, 2,—Vol. IIL. D 34 SUMMARY OF CURRENT RESEARCHES RELATING TO SUMMARY OF CURRENT RESEARCHES RELATING TO ZO OT;O GY AND BO F Awe (principally Invertebrata and Cryptogamia), MICROSCOPY, &c., INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.* ZOOLOGY. A. GENERAL, including Embryology and Histology of the Vertebrata. Sudden Destruction of Marine Animals.t—Professor T. Rupert Jones accounts for the manner in which large numbers of marine animals have in past ages suddenly perished in their own element and been entombed: 1. (fishes) by either unusual or periodical influx of fresh water from the land; 2. by volcanic agency; 3. by earthquake- waves; 4. by storms; 5. (fishes) by suffocation, when massed together in frightened shoals, or when burrowing in sand and mud and acci- dentally buried by other sands and mud; 6. (fishes) by being driven ashore by fishes of prey; 7. (fishes and molluscs) by too much and too little heat in shallow water; 8. (fishes and molluscs) by frost; 9. (fishes) diseases and parasites ; 10. (fishes and molluscs) miscellaneous causes: disturbance of equilibrium of living and dead organisms, ferruginous springs, poisons, lightning, &c.; 11. marine life surviving in fresh-water lakes. Apparent Bird-tracks by the Sea-shore.{—Mr. T. Meehan calls attention to what appeared to be the track of a three-toed bird in the sand, near low-water mark, at Atlantic City. They were generally regarded by observers as bird tracks. While looking at them, he noted that there were no birds about to make such recent tracks, and also that the tracks would have to be made in every case by a bird facing the water, which, in the nature of things, would be improbable. While reflecting on this, he noted on the face of the smooth receding waves, spots where the water sparkled in the light, and he found this was caused by little riplets as the wavelet passed down over the half- * The Society are not to be considered responsible for the views of the authors of the papers referred to, nor for the manner in which those views may be expressed, the main object of this part of the Journal being to present a summary of the papers as actually published, so as to provide the Fellows with a guide to the additions made from time to time to the Library. Objections and corrections should therefore, for the most part, be addressed to the authors. (The Society are not intended to be denoted by the editorial ‘‘ we.”) + Geol. Mag., ix. (1882) pp. 533-40. ¢ Proc, Acad, Nat. Sci. Philad., 1882, pp. 238-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. DO exposed bodies of a small crustacean, Hippa talpoidea, and that the water in passing over the bodies, made the trifid marks which had been taken for impressions of birds’ feet. This little creature took shelter in the sand near low-water mark, and entered head foremost in a perpendicular direction downwards, resting just beneath the surface. The returning wave took some of the surface sand with it, and thus the lower portions of the bodies, uppermost in the sand, were exposed. Often the creatures would be washed out, when, recovering themselves, they rapidly advanced in the direction contrary to the retreat of the wave, and entered the wet sand again as before, their sides being parallel with the shore. The body terminated in a caruncular point which, with the position of the two hind-legs, made a tridentate obstruction to the sand brought down by the retreating wave, and the water passing around the points, made the three toe- like grooves which resembled a bird’s foot from 13 to 2 in. long. The creatures in their scrambles for protection beneath the sand, managed to keep at fair distances from each other, and hence there was considerable regularity in the tracks as if they had really been produced by birds. He added that he presented the observation as a mere trifle, but he could not help remarking that if by any means these trifid im- pressions shonld get filled with mud, and the deposit become solid rock, it would be very natural for observers, ignorant of their origin, to mistake marks like these for the tracks of birds. B. INVERTEBRATA. Anastomoses of the Striated Muscular Fibres of Invertebrates.* —M. Jousset de Bellesme has endeavoured to determine the function of the anastomoses which are found in the primitive bundles of the striated muscles of Invertebrates, the same existing in Vertebrates only in certain special organs, such as the heart. As the result of his observations on the larve of Insects and on Crustacea (more particularly Amphipoda and Isopoda) it appears first, that there is no necessary relation between the striated condition and the accomplishment of voluntary movements, as striated fibres are found in the digestive tube and its glandular appendages, and secondly, that there is a constant relation between the fact of this anastomosing and the mode of contraction of the organs which have this arrangement. From the transparency of the Crustacea studied it was seen that the contraction of the fibres of the gastric ceca exactly resembled that of the Vertebrate heart. The products of secretion accumulate in the centre of these tubes and it is therefore essential that their walls should contract simultaneously (and not one part after another) in order to expel the secretion. It is this simultaneousness in the contraction that it is the function of the anastomoses to secure, and it is not without interest to see that the same effect is produced in the muscles of both Vertebrates and Invertebrates by the same organic arrangement. * Comptes Rendus, xcy. (1882) pp. 1003-4, p 2 36 SUMMARY OF CURRENT RESEARCHES RELATING TO Mollusca. Digestion in Cephalopoda.* — E. Bourquelot continues his researches on this subject,t referring particularly to (1) the digestion of amylaceous matters and (2) of saccharose, (8) the function of the salivary glands, (4) the liver, and (5) the mechanism of digestion. The food reaches the stomach direct ; the crop of the Octopus seems to be only a kind of surplus reservoir ; there it is subjected to the action of the digestive fluids which come from the liver and the pancreas passing by the cecum. The proteid matters and the hydrocarbons are digested, the fats emulsionized, and the chyle goes directly into the intestine without passing by the cecum. At the conclusion of digestion there is found in the cecum and often even in the hepatic canals a small brown column which might be taken for digested food. It is, however, only a mass of hepatic cells detached from the gland. A similar column has already been noticed by Plateau at certain periods of digestion in the excretory canals of the abdominal gland of the Spiders. Development of Bithynia tentaculata.j—P. B. Sarasin, in his introduction, points out that although the embryos of this fresh-water Pulmonate Gasteropod are small and opaque, it is possible to make a good series of sections, in consequence of the comparatively small amount of yolk-material which is found in the endodermal cells. These are always sharply marked off, and have a distinctly cylindrical form. The rounded yellowish ovum presents an elevation which appears to be, but is not, the point at which the directive corpuscle is extruded ; indeed it is only as it disappears that the corpuscle is to be seen at the opposite pole of the egg. A period of rapid cleavage appears to be followed by one of repose; four larger polar cells are soon to be distinguished from a number of smaller ones; the gastrula, after formation, closes up again, and forms a complete and solid sphere— the pseudogerm-sphere. At its thickened part there arise two solid processes, one of which is distinguished by a slight depression on it, which soon becomes converted into the mouth. At this stage there is no indication of any velum ; when the latter does come into existence it has at first the appearance of two rows of ciliated ectodermal cells. The process connected therewith forms the foot, while the other, by an ingrowth of cells, is the seat of the future shell-gland. The author, in opposition to the views of various embryologists, expresses his belief that in all Gasteropoda the original gastrula-mouth (blastopore) becomes closed up. In the second section the velum, and primitive kidney (anse) are dealt with ; the name of anse is applied to the chords of transparent vesicular ciliated cells, which are found inserted at the sides of the mouth, and which, in the embryo, have the function both of velum and of primitive kidneys; the author devotes some attention to demon- * Comptes Rendus, xcv. (1882) pp. 1174-6, + Cf. this Journal, ii. (1882) p. 30. t Arbeit, Zool.-Zoot. Inst. Wiirzburg, vi. (1882) pp. 1-68 (7 pls.), ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 37 strating this point, and, in describing their later history, states that they at first so alter their position that the right one comes to lie almost in the middle of the neck; the left approaches towards the lower side, but does not come so near the middle line. This change in position is to be explained by the torsion of the anterior part of the visceral sac. In time the right ansa becomes altogether lost, while the left is finally an aggregate of ciliated cells, in which irregular cavities may be made out, and which are perhaps due to an internal destruction of the cells. The liver is shown to be developed from the lower cells of the blastula, and from those which became invaginated to form the gastrula, and afterwards formed a solid sphere in the pseudo-gastrula. In- vagination gave rise to two unequal portions, of which one remained solid, while the other was excavated and filled with fluid. The author finds that the whole of the enteric canal derives its elements from the ectoderm, while the liver is directly derived from the endoderm, its cells retaining throughout the whole of embryonic life the characters of true endodermal cells, distinguished by drops of deutolecithin ; these last increase in size with the cells themselves, and filling them up, press the nucleus and protoplasm towards the outer wall ; the more they aggregate in the cells, the more mucous substance is collected in the cavity inclosed by the hepatic sac. The two lobes of the liver, which are at first almost spherical, elongate considerably with the growth of the embryo. The author is not able to demonstrate, though he is convinced of, the completely medioventral position of the developing enteron; at first the rudimentary intestine consists of nothing but a collection of ectodermal cells; later on a cavity is developed in them, and this pretty rapidly extends forwards and backwards; thus we get a tube bent at an oblique angle in the middle, and attached at either end. A little later, the fore-gut bends towards the left, and the hind- gut to the right side of the embryo; the former follows the hepatic lobes, just as these follow the visceral nucleus and all the organs. This torsion is easily explained on purely mechanical principles; an elastic cord growing regularly in length will, if its ends be fixed, form a loop by torsion through 180°; and thus tensions are avoided, which would otherwise affect it. This law is called the law of torsion, and would appear to be applicable not only to the phenomena observed in Gasteropods, but also in other animals, in no way closely allied to them. The body of the loop is formed by the widened portion of the hind-gut, which will become the stomach, and this portion is so twisted round that the anus comes to be near to, instead of at the opposite pole to, the mouth. A similar change in position is effected by the shell-gland. The earliest rudiments of the nervous system are seen in what is now generally called the trochosphere stage. 'The following are the leading peculiarities of this stage in Bithynia :—The body forms a slight swelling towards the left side, the herald of the torsion; the intestine is slightly bent forwards, and lies towards the right hand ; the fore-gut is hollowed out, and communicates with the buccal 38 SUMMARY OF CURRENT RESEARCHES RELATING TO cavity; the hepatic lobes are hollowed out, and the anse project con- siderably, The ventral surface is distinguished by the pedal process, at its anterior end. Right and left of the mouth there lie two ecto- dermal elevations, which may be known as the sensory plates ; from these the cerebral and pleural ganglia of either side are developed ; a ventral median growth gives rise from before backwards to two pedal, two visceral, and one abdominal ganglion. The first of these are only secondarily connected with the cerebral and pleural ganglia; the connection between the separate pairs was primitively effected by the median outgrowth, but this becomes lost, and a secondary connec- tion takes its place. The pair of buccal ganglia arise from the ceso- phagus, and the olfactory ganglion is either developed on the right or in the dorsal median line. Attention is directed to the resem- blances and the differences which obtain between the development of the nervous system of Bithynia and that of an Annelid. The larval heart lies a little to the right side of the neck; the permanent heart may be seen to pulsate during its existence, but the pulsations are not synchronous. At the same time as that of the development of the nervous system, an ectodermal thickening on the right side of the embryo gives the first indication of the permanent kidney ; under the effects of torsion, this organ comes in time to lie on the left side; at the same time, it elongates and becomes hollow. The pericardiac cavity is formed by mesodermal cells which become contractile, and from the solid cord of cells within it the permanent heart is formed; this lies almost perpendicularly to the kidney. With regard to the germinal layers, the author tells us that the ectoderm is remarkable for never being at rest during the develop- ment of the embryo; all the organs are formed either directly or indirectly from it; the mesodermal elements do not arise at any definite and single point, and there is no evidence of any cleavage in it, and still less of the formation of a true ccelom. As the endoderm so called does not give rise to the enteron, its homology with the similarly named layer in the chick is to be doubted. Many of the author’s statements could only be made clear by the reproduction of a number of his figures. Organization of Adriatic Chitons.*—B. Haller has examined chiefly Chiton siculus and C. fascicularis. Commencing with an account of the nervous system, he finds that, in the cesophageal ring, the primary pallial and pedal nerves form a connected whole, in which ganglia and commissures are not yet differentiated; any given transverse section exhibits a cortical layer of ganglionic cells, pro- cesses from which are either continued directly into the central nerve- plexus, or pass directly into the nerve-trunks. In the nervous system, and, especially, in the region of ganglionic cells, we may observe the well-known orange-yellow coloration, which is most intense where the cells are most largely aggregated. The nerves of the upper cesophageal ring either supply the cephalic portion of the mantle, or belong to the cephalic lobes, or innervate the lips, the epithelial layer * Arbeit, Zool. Inst. Wien, iv. (1882) pp. 323-96 (8 pls.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. a9 of the anterior buccal cavity, and the buccal musculature. Of the first of these there are no less than thirteen on each side, and, as it would seem, their function is mixed. There are the same number of nerves for the cephalic lobes, and they anastomose largely with one another. The third group supply the gustatory bulbs, among other structures. The commissures of the anterior visceral ganglia arise from the lower half of the cesophageal ring, and there is also a ganglion for the “ subradular organ.” After a detailed description of other parts of this system, which would be of interest only to those acquainted with the work of v. Ihering and Hubrecht, the author passes to the nervous supply of the heart and peritoneum. If pieces of fresh tissue from the auricle are placed in sea-water and then ex- amined, large yellow pyriform cells may be seen between the muscular plexus of the heart. An aid to study was found in the use of a mixture of glycerine with a little acetic acid and water; the nerve- cells were then seen to have a very large nucleus and a distinct nucleolus ; they are generally oval, and always have a protoplasmic process; they are placed between the epithelial investment and the musculature of the heart, where they form a fine nerve-plexus of small multipolar and large bipolar cells. Observations on the peri- toneum appear to indicate the presence in it of bodies which are, physiologically, comparable to the Pacinian bodies of the Vertebrata. In an account of the digestive apparatus, attention is directéd to extremely delicate unilobular buccal glands, which are formed on its upper surface, and are not very easy to detect. Glands, to which the name of “sugar-glands” is applied, were found to open into the cesophagus, and to have a truly embryonic form, for they were simple outpushings of the enteric wall, with a single large lumen; the wall of the gland is remarkable on account of the development of villi on it. Variations in the colour of these parts are to be detected, and it appears that in the course of secretion the green colour is converted into violet, or, in other words, before the metabolic changes in the gland-cells can be effected, a chemical process is gone through, which finds visual expression in the alteration of colour. Another pecu- liarity is to be found in the fact that the secretory vesicles are not formed within the cell, but are excreted from it, without being visible, as such, within it. No definite information can be given as to the function of these glands. The epithelium of the stomach is distin- guished from that of the cesophagus by the absence of cilia; into it there open, by separate orifices, the ducts of the liver, which consist of two unequal portions; the larger and lower portion, or that which primitively lies on the right side, is a large acinous gland, in which four several lobes can be made out. The most primitive arrangements possible are to be seen in the Chitons, for there are none of the longer efferent ducts, but the liver opens directly into the stomach ; the lower wall of the upper portion of the stomach forms an infundibular invagination, and is gradually continued into the wall of the primary lumen of the liver; the orifice itself is not wide; the high epithelium of the stomach gradually disappears, and four or five circular folds appear in the infundibulum. Attention 40 SUMMARY OF CURRENT RESEARCHES RELATING TO is directed to the variations in colour of the liver of individuals of the same species of the Placophora; a lighter colour would appear to be associated with an absence of secretory activity, and observa- tions were made which led to the conclusion that the brown pigment, which is at first regularly diffused through the protoplasm, disap- pears during the process of secretion; the drops of secretion are glass-green in colour. After describing the other parts of the enteric tract, the author passes to the renal organ, which has lately attracted the attention of vy. Ihering, who looks upon it as an unpaired structure; and of Sedgwick, who maintains its paired nature. Haller completely denies the presence of openings from the kidney into the pericardium, and supposes that the ciliated infundibular orifice becomes closed in the later stages of larval life—a view which receives support from an oral communication by Hatschek as to the course of development in Sipunculus. The kidney, but not its separate lobes, are invested by the peritoneum. The heart lies under the 7th and 8th scales, and consists of a long median ventricle, which is prolonged anteriorly into the aorta, and of two auricles, which pass into one another posteriorly ; it is here that they communicate with the ventricle. The cardiac musculature forms a plexus of many-branched anastomosing muscular bundles; in the auricles it is particularly thin, and the bundles may be there seen to consist of extremely delicate fibrils ; the fibres are set parallel, except at the points where the bundles branch. There is no appearance of striation or of any investing layer. At the opening into the ventricle the muscles form a distinct valve. The musculature is not covered by any endothelium, but the muscles and the nervous elements are directly bathed by the blood. As the auricles are not set freely in the body, they are by that fact to be distinguished from the similar organs of other Gasteropods. As to the course of the circulation, it is found that the blood is collected from the whole primary ccelom by a bilaterally disposed transverse lacuna, set a little behind that of the branchial vein; it passes into a longitudinal duct, which lies beneath the nerve-cord, and is set parallel to the long duct of the branchial vein. A rich lacunar system, in free communication with the primary cclom, is to be found in the foot. When the blood is driven out of the ventricle it makes its way into the aorta, whence by simple openings (?) it passes into the primary ccelom, or, by pedal vessels, into the foot. The venous blood from the latter is driven, by its contractions, into the branchial artery, and so to the auricles. The blood-corpuscles are uncoloured. he term secondary ccelom is applied to the cavity beneath the genital gland and the pericardium in which the liver and intestine appear to lie; owing to the reduction of the superior and inferior mesenteries, these organs have a closed investment. These partitions are, however, present on the rectum, and prove that there are two coelomic sacs into which the digestive apparatus is invaginated. The author concludes with some observations on the relation of ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 41 the Chitons to Neomenia, in which he opposes the doctrine of y. Ihering, that the former are derived from the latter, and holds that the two are separately evolved groups, related only by the posses- sion of a common ancestor. Generative Organs of Oysters.*—P. P. C. Hoek finds, as his most remarkable result, that the generative organs of oysters are not localized glands, but are distributed over the whole surface of the body ; they are not separated from the integument on the sides of the body, and in front of the pericardiac cavity there is a dorsal and a ventral connection between the two halves of the organ. We every- where meet with ramifications, which are in communication one with another, and have the internal wall forming internal culs-de-sac; the epithelial cells of these are converted into eggs or spermatozoa, both of which are produced from the same cell. The external longitudinal cleft, described by Lacaze-Duthiers, leads into a genital canal, which begins to ramify near the orifice; the branches ramify afresh, and extend over nearly the whole of the surface of the body. ‘There is no trace of any genital papilla, and the orifice serves also for the organ of Bojanus. As to this last, the author states that it does not form a very distinct organ; it is composed of intercommunicating mem- branous folds, which open into a cavity lined by ciliated epithelium, and leading by a small canal to the urogenital orifice. In the wall of this cavity there commences a narrow canal, which runs almost parallel to the genital duct, and opens into the so-called pericardiac cavity. The author believes that the female products are often ferti- lized before they escape, and that the oyster is not only morpholo- gically but also physiologically dicecious. Molluscoida. Early Development of Salpide.t— FF. Todaro, in his second preliminary communication, states that he has found that the follicle is divided into two sacs, which communicate freely with one another ; one is at first much larger than the other, and may be known as the ovarian sac, as it contains the ovum during the whole period of its maturation ; the other is very small and empty, and appears as though it were merely a small introflexion of the larger one. As the ovarian sac diminishes, it grows in size, so as to be able to receive the ovum, which remains in it during the period of segmentation. We may, therefore, call it the embryonic sac; it is provided with an organ of attachment, by means of which it is able to attach itself when it passes into the uterus. The author does not now go into detail with regard to the various stages of the development of the ovum, but merely states that he has observed the entrance of a single zoosperm, its conversion into a male pronucleus, and its fusion with the female pronucleus to form the segmentation-nucleus; the nutrient material of the egg is obtained from the epithelial cells of the ovarian sac. The same * Comptes Rendus, xcv. (1882) pp. 869-72. + Arch. Ital. Biol., ii. (1882) pp. 1-9. 42 SUMMARY OF CURRENT RESEARCHES RELATING TO layer in the embryonic sac furnishes the nutriment for the first six blastomeres; these then proliferate, and give rise to small lecithal cells; segmentation is unequal, and division alternates with gemmation; the lecithal cells form a peripheral layer to the morula, and also extend inwards between some of the blastomeres; growing rapidly, they at last surround each of the fourteen blastomeres; they then penetrate into the blastomeres themselves, and those that do so disappear. At a later stage the blastomeres become broken up into small protoplasmic cells, which are only distinguished from the nutrient ones by the characters of the protoplasm; they soon increase greatly in size, and again increase by gemmation. Meanwhile changes are being effected in the sac, and we get in time to an embryo which, larger in size, rounded in form, and placed in the uterus, begins to be differentiated into its separate parts; the primitive intestine, the blastoccel, and the amnios are set up, and then the embryonic and blastodermic membranes begin to be developed. The essential parts of all the subsequent changes not here described in detail are stated to lie in the multiplication of the segmentation cells, and in the absorption of the lecithal cells, which serve to nourish them; on the ruins, as it were, of these latter the segmentation cells give rise to embryos; first of all, to the solitary, and then to the compound Salpa ; in other words, there is a metamorphosis, and the details of the rela- tions of the proembryo to the true embryos differ in different species, on the comparative study of which the author promises to enter on another occasion. Compound Ascidians of the Bay of Naples.*—A paper on the anatomy and development of these animals by Dr. A. Della Valle is reported on by MM. Trinchese and De Sanctis. In the genus Distaplia Della Valle,{ the colony is either sessile or pedunculate ; the individuals are arranged in ramified masses resembling the Didemnide. The branchial sac has four series of openings; the stomachal walls are smooth; the heart is placed at the apex of the curve of the intestine; the sexual glands lie on the right side, somewhat above the heart; the testis is developed before the ovary and simultaneously in all the members of a colony, so that the colonies are always found either exclusively male or female. The mature ova are collected in the cloaca, whence they fall into a special diverticulum, which developes at this time and is subsequently detached from the animal. The larve are gigantic and produce buds; these are formed by a bending outwards of the external wall of the peritoneal sac, not far from the end of the endostyle; the bud soon separates from the individual which produced it and wanders towards the circumference of the colony, dividing by fission, and thus adding new individuals to the colony. Della Valle, dealing with the tail of the larva, finds by transverse sections that the axis consists of a cylindrical canal filled with a transparent liquid, which is perhaps * Atti Accad. Lincei (Rome) Trans., vi. (1881) pp. 14-5. + See this Journal, ii. (1882) p. 768, where an account of a paper on this genus is given from the author’s description, differing somewhat from the present one. eld 9 ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 43 identical with that which bathes the surrounding cellular structures ; Kowalewsky and Kupffer had described the corresponding structure in some other Ascidians as a solid gelatinous body. As observed by Hertwig, amceboid cells migrate from the ectoderm into the common mantle. A single Ascidiozooid was found to consist of an internal endodermal sac and of a bilobate peritoneal sac which communicates on one side with the endoderm by the branchial openings and on the other with the exterior by the cloacal tube ; the muscular fibres lie between the outer lamina of the peritoneum and the ectoderm, as also do the heart and the reproductive glands; the products of the latter are transferred direct to the body-cayvity. The existence of a mesentery and the method of development of the buds and of the embryo which results from the ovum, demonstrate con- elusively that the Ascidians belong to the enterocelic type. The glandular character of the endostyle is confirmed. The circulation of the blood is wholly lacunar. Special attention is given to the repro- ductive organs of the compound Ascidians; in particular may be noted the formation of a special oviduct in the Botryllide, analogous to that of the Salpe, and the remarkable form assumed by the testis in Aplidium; in the post-abdomen of the latter are found all the elements of the primordial body-elements, viz. ectoderm, endoderm, and peritoneal sacs. In a young Botryllid the nerve-ganglion was observed to be in direct connection with a prolongation of the ciliated fossa ; the muscular system in this form consists of smooth fibres, placed between the ectoderm and the outer wall of the peritoneum. The processes of rejuvenescence and of formation of new individuals in compound Ascidians are described with great clearness. Metsch- nikoff’'s discovery of the origin of the bud of Botryllus from the parietal layer on the right and left sides is confirmed, and the forma- tion of the enterocele described. In the simple Ascidians, the peritoneal sacs arise directly from the intestine and not from the ectoderm, as maintained by Kowalewsky. New Division of Cheilostomatous Polyzoa.*—Dr. J. Jullien considers that a character of capital importance has hitherto been neglected by all authors, 1. e. the ectocyst. The Membranipora lineata of Linnzus is constructed on an absolutely different type from that of M. antiqua of Busk, but both are united in the same genus with M. calpensis, which represents another type still, though derived from the second. Turning to the characters of the ectocyst we find in M. lineata a simple ectocyst that is not divided into two layers, and true avicularia ; in M. antiqua there are two ectocysts, one external and the other (cryptocyst) internal, having between them a solution of continuity or hypostegia, no spinules but onychocellaria or false avicularia. ‘To this latter type belong a number of cretaceous and some tertiary species which have hitherto been placed in numerous genera, according to the form of the zoarium. For the opening of the cryptocyst the author proposes the useful name “ opesia,” pointing out that the term “aperture” has been used both for the oral aper- * Bull. Sce.. Zool. France, vi. (1881) pp. 271-85 (5 figs.). 44 SUMMARY OF CURRENT RESEARCHES RELATING TO ture and for the large opening in the front of the calcareous wall of the Membraniporide, &c. The author proposes to divide the Cheilostomata into two tribes according to the character of the ectocyst, adopting the view of most embryologists that the ectocyst of the larva produces the calcareous test of the zocecium and the endocyst the polypide. We have then the two divisions of Monoprrmata (simple ectocyst) and DipLopER- maTA (double ectocyst). Itisintended at some future time to examine all the families of the Diplodermata, but at present the author only deals with one which he calls Onychocellide. The type of this is Membranipora angulosa, which he re-names Onychocella marioni Jull., considering the onycho- cellaria to be of great classificatory value. The family is divided into eight new genera; these, however, seem largely based upon the figures in D’Orbigny’s ‘ Paléontologie Francaise, and we think that Dr. Jullien would sometimes find that the older portion and the growing part of the same specimen would have to be placed in separate genera, as the shape of the zocecia and of the opesia is largely used as a generic character. This is certainly a suggestive paper, and although all the con- clusions of Dr. Jullien may not be accepted it may lead to several important characters receiving more attention, and the classification now in use may be much modified thereby. New Type of Polyzoa—Cephalodiscus.*— Prof. M‘Intosh describes a new type of Polyzoa allied to Allman’s Rhabdopleura dredged in the ‘Challenger’ expedition, for which the name of Cephalodiscus dodecalophus is proposed. It differs from Rhabdopleura in regard to the ccencecium, in the much greater size of the buccal shield, in the remarkable branchial or tentacular plumes, in the structure of the pedicle, and in the perfectly free condition of the polypides. Cephalodiscus and Rhabdo- pleura agree in the absence of the calyciform membrane connecting the bases of the tentacles, in the position of the mouth, which opens ventrally behind the buccal shield, in the general structure of the alimentary canal, and in the position of the anus. The development of the young buds is similar. Both connect the ordinary Polyzoa with Phoronis. Cephalodiscus naturally falls under Professor Allman’s section Polyzoa Aspidophora, and further demonstrates the correctness of that author’s opinion in regard to the systematic position of these anomalous forms. The following is the diagnosis of the genus:—Ccencecium con- sisting of a massive irregularly-branched, fucoid secretion resembling chitine, hispid with long spines of the same tissue, and honeycombed throughout by irregular apertures, channels, and spaces, in which the separate and independent polypides occur singly or in groups. Lophophore richly plumose, with an enormous buccal shield and large oral lamella, the mouth opening between the two. Anus on the interior dorsal prominence, behind the plumes. Two large eyes * Ann, and Mag. Nat. Hist., x. (1882) pp. 337-48. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 45 abutting on the ovaries. The homologue of the funiculus is short and quite free, its tip serving for the development of buds. Vitality of Fresh-water Polyzoa.*—Dr. H. Allen calls attention to tenacity of life as exhibited in a fresh-water Plumatella (P. vesi- cularia Leidy). The leaf of the lily on which the colony had fixed itself, had been, by accident, removed from the water of the aquarium, and had been exposed for sixteen hours to the air. The animals had apparently become dry, and the colony itself barely visible to the unaided eye. Upon being again immersed (in water that chanced to be impregnated with iron-rust), the animals revived and flourished for two weeks, at the end of which time they perished from the effects of the decay of the leaf on which they were growing. The following facts are of interest in this connection. First, that in these animals, relatively high in organization, aeration may go on for a number of hours by means of the retracted tentacles in the small amount of water contained within the cells. Second, that the presence of oxide of iron in the water does not interfere with the growth of the animals. And third, that the genus Plumatella may be found to resemble other mollusc-like creatures, not only in their plan of organization, but in their habits of sustaining life for long periods after removal of the animals from water. The last-named fact may possibly enter into questions of geographical distribution of this and allied forms. Observations on Living Polyzoa.t—Mr. C. M. Maplestone de- scribes observations made upon specimens either dredged, obtained from old piles, drawn up from the pier, or washed up on the beach. While some of those dredged, or carefully collected from the piles, and immediately transferred into bottles of sea-water, never expanded, many of those found on the beach and not expected to be alive did so. On filling a large bag with Polyzoa, and making a preliminary examination with a Coddington lens in the evening, some of the animals were found to be moving within the cells, and on transferring them to the zoophyte trough several species expanded. The author thinks it useful to mention this, as it may not be generally known that if Polyzoa are gathered soon after being washed up on the beach, or before getting dry, and are afterwards kept merely damp, there is a probability of finding them living, and he has often since found them so. Arthropoda. a. Insecta. Polar Cells of Insects.{—M. E. G. Balbiani has followed all the phases of the transformation of the polar cells in a Chironomus, and considers himself to be in a position to determine the precise signifi- cance of these elements. After tracing the process of development from their first appearance to the moment when the larva is hatched, * Proc. Acad. Nat. Sci. Philad., 1882, pp. 223-4. + Trans. and Proc. Royal Soe. of Victoria, xviii. (1882) pp. 48-51 (1 pl.). } Comptes Rendus, xev. (1882) pp. 927-9. 46 SUMMARY OF CURRENT RESEARCHES RELATING TO he points out that it is impossible not to recognize that we have to do with the generative organs of the animal, which have their origin in the polar cells. From this mode of development flow some interest- ing results with regard to the general morphology of the reproductive organs. There is first their very early formation, preceding that of all the other organs of the embryo, and indeed even that of the embryo itself in its most rudimentary form, the blastoderm. There is then the community of origin not only of the male and female sexual products, but of those and of the embryo, We may therefore say that the ovule, the spermatozoid, and the embryo have the fecun- dated ovum as their common origin; but whilst the latter is capable of being directly developed, the two former only acquire the aptitude for development by their reunion in a new fecundation. Embryonic Development of the Bombycini.*—The type chosen by S. Selvatico to illustrate this subject is Bombyx mori ; the ova of Attacus mylitta and Saturnia pyri were also examined. The following is the structure of the ovum at the end of winter :—(1) Solid globule, attached to an opaque substance on its inner aspect. (2) Transparent structureless membrane, considered by some as secreted by the blas- toderm, but found by Tichomiroff before the appearance of the blastoderm, (3) Serous envelope, consisting of large, flattened, nucleated, polygonal cells containing pigment. (4) Nutritive yolk, forming large spheres which contain one or more protoplasmic nuclei. (5) Blastoderm, the ventral side turned outwards and covered by the amnion. The amnion appears as a membrane with large nucleated cells like those of the serous envelope, but without pigment. The Malpighian vessels originate in the ectoderm. Selvatico was perhaps prevented by the thickness or large size of the blastoderm in the above Bombycini from noticing the early appearance of the rudiment of the genital glands, which was observed by Balbiani in Tinea crinella. Asymmetry of the Nervous System in Larve.j— Anna K. Dimmock, in dissecting a number of the larve of Harpyia (Bombyx) vinula, found that the nervous system, instead of extending in a direct line in the ventral region, as is common in insect larve, curved out- ward laterally between the first and second thoracic ganglia, This curving, which was toward the left in six larve examined, is to avoid interference with the duct from a sac, or gland, which opens out between the first and second thoracic ganglia. The gland secretes a liquid, said to contain salicylic acid, which the larva ejects, as a means of defence, when disturbed. The duct of this gland opens by a transverse cleft, figured by Miiller,{ on the ventral side of the first segment posterior to the head. * Bollet. Bachicultura, viii. (1881) (7 pls.). Cf. Bull. Soc. Entomol. Ital., xiv. pp. 250-1. + Psyche, iii. (1882) pp. 340-1 (1 fig.). O. F. Miiller, ‘Pile-Larven med dobbelt Hale, og dens Phalene,’ Kjobenhayn, 1772, pl. 2, fig. 3, d. Cf. also J. R. Rengger, ‘ Physiologische Untersuchungen iiber die thierische Haushaltung der Insecten,’ Tiibingen, 1817, pp. 35-6. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 47 In the earlier stages of the larve the nervous system turns con- siderably out of the direct line, in order to allow the duct of the gland to pass; but, in the full-grown or nearly full-grown larve, it is nearly straight, although still distinctly unsymmetrical. This lessening of asymmetry, as the larva grows, is due to the duct being somewhat smaller in larger larve, in proportion to the size of the larva, thus allowing the nervous system to settle back, more or less, into its normal position. ; This kind of asymmetry has not been found, the author believes, in any other Arthropod, but, upon the suggestion of Prof. Leuckart, she examined Hirudo medicinalis, the blood-leech, the nervous system of which has an analogous asymmetry. The genital organs are in such a position as to necessitate the pushing of the nervous system slightly to one side, near their outlet. Of four specimens of Hirudo examined, two had the nervous system to the right and two to the left of the genital organs; but of six specimens of Harpyia dissected, all had the commissure between the first and second thoracic ganglia deflected toward the left. Vitality of Insects in Gases.*—From the apparent indifference of some insects to foul and poisonous emanations, as well as the vary- ing sensitiveness of others under similar conditions, it would seem reasonable to conclude that there is a substantial difference in the delicacy of their respiratory functions, which might be indicated approximately by subjecting individuals of various groups to artificial atmospheres of deleterious or irrespirable gases. This opens a wide field of experimentation both in the methods employed, the reagents used, and the insects examined. More from curiosity than any other motive, Mr. L. P. Gratacap has made some trials in this direction, the results of which he tabulates, though they have not been extended enough to admit of any very interesting deductions. The gases used were oxygen, hydrogen, carbonic oxide, carbonic acid anhydride, prussic acid vapours, nitrous acid fumes, chlorine, laughing gas (nitrous oxide), illuminating gas, and ammonia. In oxygen the insects at first showed slight symptoms of exhila- ration, “ accompanied with a restless inclination to jump”; but this passed away, and they seemed totally unaffected by the excess of oxygen, and their vitality was impaired only after long exposure to its influence, due in some cases as much to the confinement. Flies (Musca domestica) lived 29 hours; Colorado beetles and meal bugs were con- fined 3 days, and then revived completely; Phalangium dorsatum lived 24 hours; Noctua 1§ day; and the common yellow butterfly (Colias philodoce) died in 12 hours, possibly as much from the effects of its own violence as from the gas. In hydrogen the flies were at once paralysed, and though apparently dead, were alive “for a lon time” afterwards. Noctua and a black wasp died at once, but Colorado beetles evinced wonderful vitality, and revived thoroughly after almost 2 days’ immersion. In carbonic acid anhydride, flies at once died, while Colorado beetles recovered after 3 hours’ exposure, * Amer, Natural., xvi. (1882) pp. 1019-22. 48 SUMMARY OF CURRENT RESEARCHES RELATING TO and after 45 minutes’ exposure in carbonic oxide. Prussic acid vapours and nitrous acid fumes killed quickly, though the Colorado beetle resisted the attacks of the former more stubbornly than any other insect. Dense chlorine was also very fatal, but the beetles lived in an atmosphere overpoweringly odorous of it for an hour, and partially recovered on their release. In nitrous oxide the beetles lived 2 hours only, while the young of the common grasshopper (Caloptenus femur- rubrum) were confined 2 hours, and were but little affected; Noctua died in 14 hour. In illuminating gas the beetles were instantly prostrated, but after an hour’s immersion some recovered ; croton bugs (Ectobia germanica) recovered after } an hour, the young grasshoppers after an hour, and flies after 5 minutes. Mouth-organs of Sucking Insects.*—Basing his remarks on the Aphide and Hemiptera, and especially on the Diptera, Dr. K. Kraepelin, in a preliminary account of his investigations, finds these three groups distinguished by characteristic arrangements of their sucking-tube. In Bombus the tube is composed of the labial palps and the maxilla, which are connected with them by strips of substance; near their lower margin the paraglosse intervene between the palps and the maxilla. The half-canal formed by the upward curve of the margins of the labium gradually disappears towards the posterior part of the latter, and allows liquid which has passed down it to escape between the labium and maxille into the mouth, at the point of origin of the paraglosse. Besides the tactile hairs certain peculiar clavate pale hairs are placed on the apex of the labium, which appear from observations to be analogous to the olfactory hairs of the inner pair of antenne of Crustacea, and as they carry a minute opening at their ends, must be considered as either gustatory or olfactory organs. ce that of butterflies, the sucking-tube of the Hemiptera is made up exclusively of the two maxille, which unite in such a way as to form a double cylinder, the upper division of which carries the food, the lower the salivary secretion. The mandibles le by the side of the maxille, and can move about on the tube. The end of the labium is provided with terminal nervous organs. In the proboscis of the Diptera the sucking-tube is formed mainly by the labrum, which con- sists of a demi-canal, closed below partly by the mandibles which are connected with it by a groove-and-ridge joint and partly by the hypo- pharynx, which runs below the mandibles, carrying the salivary canal ; on each side below the hypopharynx lie the maxille. Dealing with the mouth of Diptera at greater length, Kraepelin dissents from Dimmock’s and Meinert’s view, that the labrum is here made up of the labrum proper and the epipharynx; the paired organs described by Meinert in Hippobosca, &c., as an independently formed epipharynx, are here regarded as enormous developments of the cheeks, The muscles of the proboscis in Musca consist of—(1) Retractor of the fulcrum, and thus of the whole proboscis. (2 and 3) Extensor and flexor of the labium. (4 and 5) Elevator and depressor of the * Zool. Anzeig., v. (1882) pp. 574-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 49 labrum. (6 and 7) Upper and lower pairs of retractors and expanders of the labella. (8) An upper pair acting in opposition to 6 and 7. (9) Compressor of the end of each labellum. (10 and 11) Depressors of labial and labral channels respectively. (12) Band uniting apophysis of labrum to fulcrum. (13) Elevator and depressor of palps. (14) Dilator of pharynx. (15) Opener of salivary duct valve. The “ pseudo-traches ” of the labella appear to consist of a system of tubes, each provided with a narrow longitudinal slit, through which the saliva is rapidly spread over the surface of the labella, and which by the capillary action caused by their narrowness produce adhesion of the saliva to the surface; the tactile hairs of the labella are con- nected with nerve-endings; and between the “ pseudo-trachezx ” are sunk double chitinous cylinders entered by nerve-endings, and pro- bably to be regarded as taste-organs ; a large salivary gland lies at the base of the labella. With regard to the pumping arrangements of the salivary glands and the sucking apparatus of the pharynx, the author supports previous observers. Large air-receptacles are placed in the fulcrum, labium, and head. Scent-Organ of Papilio.*—Mr. H. Skinner has observed that the larvee of Papilio turnus and P. troilus, when irritated, project from a slit in the prothoracic segment an orange-coloured bifid organ. The apparatus is a scent-organ, and gives out a strong and disagreeable odour perceptible at some distance, and seems to be designed to defend the caterpillar from numerous enemies. The anatomy of the organ seems to have escaped investigation, as most authors merely mention its existence, one describing it simply as fleshy. It has the appearance of being a solid organ, but it is in reality hollow throughout the entire extent, and of very thin texture, tapering gradually to a point. It is drawn in by invagination, and is protruded after the same method. If the larva be held so that sunlight may pass through the extended organ, the progress of intus- susception may be distinctly seen. Anatomy of Aphides.t—E. Witlaczil describes the fat-body of the Aphides as being especially well developed in the abdomen, where it forms a thick layer under the skin; the large cells of this tissue contain a number of fat-drops, present in such numbers as to render the protoplasm and the nucleus scarcely recognizable in fresh specimens ; the whole tissue has a spongy appearance. The fat-drops are often coloured green or red, and frequently greatly affect the coloration of the species. As in other insects, the musculature of the abdomen is ‘ divisible into a motor and a respiratory group; from the stigmata there pass up obliquely a group of two or three muscles, while a second group passes towards the middle line, and another muscle, attached a little behind the stigma, passes up backwards to the dorsal surface. There are nine pairs of stigmata; from the first a well- developed tracheal trunk proceeds forwards to supply the head, and * Proc. Acad. Nat. Sci. Philad., 1882, p. 239. t Arbeit. Zool. Inst, Wien, iv. (1882) pp. 397-441 (2 pls.). Ser. 2.—Vot. III. E 50 SUMMARY OF CURRENT RESEARCHES RELATING TO gives off a number of branches. Three transverse anastomoses are to be found in the thorax. The brain is proportionately large, and nearly fills the head ; seen from above it is bilobed; and from the lateral lobes there arise the optic nerves. At the hinder end they are connected with a large cellular mass, which lies on the anterior end of the cesophagus, and is the frontal ganglion of the sympathetic nervous system. The median large lobes of the brain are continued backwards into two nerve-cords, which embrace the cesophagus, and unite below to form the sub- cesophageal ganglion. The large compound eyes contain nume- rous crystalline cones, pigmented at definite intervals; at the hinder margin three cones are separated off, and these, which are stronger but shorter than the others, are each surrounded by a con- tinuous layer, and, with a projecting stalk, form an eye. In the apterous generations of Pemphigus the optic organ is solely represented by these three cones, the compound eye being aborted, in correlation with their mode of life. The number of joints in the antenne have been wrongly used as a means of separating the genera; the author finds that there are constantly six joints, for in Pemphigus the winged forms have six and not five. The olfactory pits would seem to serve, not so much for finding the female as for detecting food. In Pemphigus bursarius the separate wax-glands are found at equal distances from one another on the back and sides of the animal; on the prothorax there are four, on the meso- and metathorax and the first six abdominal segments, six, on the seventh there are four, and on the restnone. The glandular tubes, which form a projection into the body- cavity, have each a cylindrical lumen ; the hollow wax-threads of one gland form a bundle; the development of these organs is found to be correlated with the abortion of the honey-tubes, and the habitation of galls by their possessors. The remarkable and characteristic sugar- tubes are placed on the fifth abdominal segment, and extend laterally to the hinder end of the body ; they vary in form in different genera, and may be well used as a means of distinction. The hypodermis of the body is continued into them, and secretes a cuticle ; the whole tube is traversed by a muscle which takes its origin from the hinder margin of the sternum of the sixth abdominal segment; by its contraction the tube is directed forwards, and some of the contained sugar-cells expressed. These last are of some size, and contain a finely granu- lated protoplasm, with nucleus and nucleolus; they secrete spheres, which, at first small, soon form a large, spherical, highly refractive and variously coloured mass. Under the influence of the air the sugar crystallizes into fine needles, which traverse the cell-wall and form a group outside it. With regard to the sucking apparatus, the author is of opinion that the rudiments of the mandibles and first pair of maxille are not lost, but are sunk into the body, where they form the so-called “ retort- shaped organs”; these, when fully developed, have an outer invest- ment of flattened cells, which is continued into the epidermis of the body, and consists of a compact mass of pretty large nucleated cells, which secrete at the periphery a chitinous substance, which hardens ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 51 in contact with air and forms the seta. The sucking apparatus of Aphides has much resemblance to, but is simpler than that of the Coccide. After a description of the digestive apparatus and the Malpighian vessels, the author states that the dorsal vessel cannot be made out either in adult or in larval forms; in the embryo, however, as Mecznikow has shown, it may be recognized as a long tube, the wall of which consists of a single layer of small flattened cells, fused with one another; very thin muscular fibres pass, rather irregularly, along and obliquely across it. With regard to the generative organs, the present investigations have led to results far from accordant with those of Balbiani; thus the “antipodal” cell could not be detected, but in an advanced stage of development a rounded protoplasmic-body at the hinder pole of the ege was observed to have the same characters as the peripheral pro- toplasmic layer. Germinal vesicles were on many occasions distinctly seen. The formation of the blastoderm proceeds from behind forwards, and cleavage is essentially equal. Lampyride.*—H. Ritter v. Wielowiejski finds that :— 1. The tracheal end-cells discovered by M. Schultze are not, as their name implies, true endings of the respiratory tubules, for they ramify into still finer capillary tubes, in which the chitinous spiral support is absent; these latter are very long, and, invested by their peritoneal membrane, are largely distributed in the luminous tissue. 2. It is only comparatively rarely that the “tracheal capillaries ” end blindly in the luminous organs; they more generally anastomose with one another, and form a kind of irregular plexus. 3. These structures do not, however, make their way into the interior of the parenchymatous cells, but extend richly over their surface, where they form irregular loops. 4, The “tracheal end-cells” are nothing more than the enlarge- ment of the membranous peritoneal layer at the base of the tracheal capillaries, which radiate out from a trachea with a chitinous spiral ; and the whole arrangement may be homologized with certain embryonal conditions of the tracheal system. 5. The “ end-cells”’ do not form the seat or the starting-point for the development of the light. Although this phenomenon may first appear in their vicinity this is only because a large store of oxygen has been laid up in them. 6. The luminous property is essentially connected with the parenchymatous cells of the luminous organs, and is due to the slow oxidation of a substance formed by them, under the control of the nervous system. 7. The parenchymatous cells, from which the two layers found on the ventral luminous organs are formed, are exactly comparable in their morphological characters; and the difference between them is solely due to the chemical characters of their contents. * Zeitschr. f. Wiss. Zool,, xxxvii. (1882) pp. 354-428 (2 pls.). E 2 52 SUMMARY OF OURRENT RESEARCHES RELATING TO 8. Some, if not all, of the parenchymatous cells are in connection with fine nerve-ramules. 7. The luminous organs are, morphologically, equivalent to the fat-body. The author’s most successful preparations were made with osmic acid, living and luminous specimens being placed in 0-1 tol per cent. solutions, or were subjected to its vapour; after washing with dis- tilled water they were placed in alcohol or in a mixture of alcohol and glycerine. Good preparations were obtained by colouring with hematoxylin or picrocarmine, or by the methyl-green solution recommended by Mayzel and Strasburger. It is of interest to observe that the author thinks that the layer of cells free from uric acid may become converted into an uric-acid series; and he bases this suggestion on the fact that the boundary line between the two is very irregular, and that the cells of the one set often project into the other; there is, too, a very considerable variation in the thickness, the dorsal being in some specimens much thicker than the ventral, and vice versd. Physiological evidence is, however, still wanting to complete the proof. The characters of the lateral luminous knobs found in the female of Lampyris splendidula are discussed, and it is pointed out that they occupy the only position in which it would be possible for their light to pass upwards and sideways; the organs of the larve of this species are distinguished from those of L. noctiluca by not being confined to one segment of the body, but existing over the whole of the abdomen ; in structure they appear to be similar to those of the female, but they are smaller in size. The adult species of Lampyris appears to be characterized by the frequent presence of organs which, in other Insects, are only found in the larve ; as examples, we may cite the tracheal end-cells, and the large cells which lie almost freely in the body-cavity, instead of being united with tissues ; so again in the fine, transversely-striated muscular fibres of the female of L. splendidula we find one or two large, clear, semilunar swellings, with granular contents and a large nucleus; these cannot be regarded as anything else than the remnants of the embryonic formative cells, from which the muscles have been differ- entiated. Yet again, the soft and wingless females are externally but little more highly developed than the larve. It cannot be doubted that the luminous power is a secondary sexual character, and its possession by the larvz is perhaps to be explained by their poisonous nature, so that they warn the insects that might attack them. 8B. Myriopoda. Existence of a Blastopore and Origin of the Mesoblast in Peripatus.*—The late Professor F. M. Balfour was just before his death engaged in the preparation of a monograph on the anatomy and development of the members of the genus Peripatus, together with an account of all known species, and he left a series of notes, com- * Proc, Roy. Soc., xxxiy. (1883) pp. 390-3. Cf, Nature, xxvii. (1882) p. 215. EE eg ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 53 pleted MSS., and drawings, which it is intended to publish in the ‘Quarterly Journal of Microscopical Science’ for April. His dis- coveries, however, on the early embryology of P. capensis are so interesting that a preliminary note has been communicated to the Royal Society. The results are shortly as follows :—That a widely-open slit-like blastopore is formed in the early oval embryo, which blastopore, occupying the median. ventral line, becomes closed in its centre, an anterior portion remaining open as a mouth, whilst a posterior portion apparently becomes the anus. The mesoblast is formed from the hypoblast at the lips of the blastopore, and makes its appearance as a series of paired hollow outgrowths from the cavity of the archenteron. This most primitive method of the formation of the mesoblastic somites, closely similar to that occurring in Amphioxus and other ancestral forms, is of the greatest morphological significance, and it is especially interesting to find that it survives in an entirely un- modified condition in Peripatus, the adult organization of which- proves that it is a representative of an animal stock of the most remote antiquity. Mr. A. Sedgwick, by examining some embryos in Prof. Balfour’s collection of material as yet uninvestigated, has been able to confirm his results, and also by finding earlier stages to verify certain points in the developmental history which rested, at the stage at which Prof. Balfour’s inquiry ceased, mainly on inference. In the discussion which took place on the paper, Mr. Sedgwick pointed out the close resemblance of the early embryo Peripatus with open blastopore to an Actinia, the mesoblastic pouches corresponding to intermesenterial cavities, and the blastopore to the mouth, and urged that the discovery tended to confirm Prof. Balfour’s published theory as to the origin of the bilateralia from the elongation trans- versely of a disk-like ancestor, the ventral nerve-cords having been formed by the pulling out into long loops of a circumoral ring. Prof. Lankester considered that the view that the blastopore represents a structure which in an ancestral form acted as a mouth, must be abandoned. The blastopore is very probably merely an aperture necessarily formed in the process of production of the hypoblast by invagination, and has never had any special function. Prof. Huxley also. pointed out the essential difference between the peripheral nerve- ring of Hydromedusz and a true circumoral nerve-ring. Formation of Prussic Acid in a Myriopod.*—A foreign Myriopod occurring in hothouses in Holland, and identified as belonging to the genus Fontaria, has the power of secreting this substance. Attention was called to this animal by its emitting a distinct odour of oil of bitter almonds when excited ; the odour is especially apparent when it is crushed. Maceration of specimens in water showed at once that the smell was due to this acid, it being detected in the water. A series of experiments have been made by C. Guldensteeden-Egeling to test re Pfliiger’s Arch. f. Physiologie, xxviii. p. 576. Cf. Naturforscher, xv. (1882) p. 433. 54 SUMMARY OF CURRENT RESEARCHES RELATING TO the hypothesis that the Myriopod secretes a material which under certain conditions is decomposed and gives rise to hydrocyanic acid as one of its products; the hypothesis has been entirely confirmed. By the use of various reagents a body has been shown to exist which is broken up by water and yields HCy among the products of its decomposition. Further, it seems probable that the species in question contains another substance which acts as a ferment; this may perhaps be isolated by future experiments. Embryology of the Chilopoda.*—N. Sograff’s account of the earlier stages of the development of the egg of the Chilopoda is derived from a study of two species of Geophilus (ferrugineus and proximus, Koch) whose ova are better than those of Lithobius for the purpose. The ova of G. ferrugineus have a fine ruby-red colour and are almost perfectly transparent; they are probably the same as those figured by Metschnikoff in his researches. Parthenogenesis appears to occur in this case, as males were not found at the end of April, but only females, of which three had empty receptacula seminis, whilst at the beginning of June eggs were produced by some of these females and commenced their development. While in the oviduct the egg is enveloped in a transparent coat which appears to consist of the united chorion and yolk-membrane, for these structures can be distinguished in young ovarian ova: At this stage the egg is filled with yolk, hiding the germinal vesicle and yolk-nucleus; but on one occasion a nucleated mass of protoplasm —the nucleus being spindle-shaped, and exhibiting division of its chromatin into two groups of rods—was found in the centre, probably derived from the germinal vesicle. The nucleus and protoplasm divide into a considerable number of portions ; the central cleavage- masses are round or polygonal, the peripheral ones stellate. Yolk- cleavage now takes place, the yolk breaking up into pyramidal masses, asin the Decapoda, these masses carrying portions of protoplasm upon their apices; the segmentation is not dichotomous; the number of pyramids was always the same and the only difference between the young and the perfect pyramid consists in an indefiniteness of outline in the apex of the former. The simultaneous origin of these masses is not an impossible circumstance, and is explained by the action of the central protoplasm in drawing in to itself the superincumbent yolk. The protoplasm-masses of the yolk now sink into the pyramids which form the primary endoderm, and the central protoplasm-masses come to the surface of the ovum and form the primary ectoderm. In the Chilognatha, judging from Polydesmus, the method of formation of the blastoderm more resembles that of the Crustacea and Arachnida ; the yolk-cleavage appears to have been correctly described by Metsch- nikoff. The blastoderm of Geophilus consists at first of large, pale, very thin cells, dividing very rapidly, so as to form, in the course of 24 hours, a number of very small cells, which are, however, smaller on one side of the ovum than on the other; on this side the primitive * Zool. Anzcig., v. (1882) pp. 582-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 55 streak appears, beginning at its anterior end, which developes the first segments and appendages before the hinder portion is clearly defined. Before the appearance of the primitive streak the mesoderm is divided off from the small-celled ectoderm and at the same time nuclei, in- vested by masses of protoplasm, emerge from the yolk-pyramids and apply themselves to the mesoderm; these masses seem to be derived from the nucleus of the ovum and to have hitherto remained at the centre. ‘The mesoderm, like the primitive streak, developes first in front. The conversion of the yolk-pyramids into endoderm, i.e. into the epithelium of the mid-gut, only takes place when the embryo is fully formed ; it commences during that stage which Prof. Metsch- nikoft did not observe, and at the same time as the commencement of flexion of the embryo. y. Arachnida. Poison-Apparatus of Scorpions.*—M. Joyeux-Laffuie finds that the poison-organ of the scorpion (S. occétanus) is formed by the last abdominal segment, where two small oval orifices serve for the exit of the poison: there are two glands, equal in size, and symmetrically arranged ; each occupies a space, covered externally by the chitinous skeleton, and having internally an anterior and a posterior mem- brane, formed by striated muscular fibres, which are inserted into the chitinous skeleton. By their contraction the poison is forced out- wards. The wall of the gland consists of a delicate layer, formed by cellular tissue and smooth muscular fibres: on its internal surface there are projecting lamelle, which increase the extent of the secreting surface; below this, is a layer of prismatic cells, which are filled with protoplasm containing in suspension and in abundance fine rounded granulations, which are characteristic of the poison of the scorpion, and hide the nuclei, which only become apparent on the addition of acetic acid; these are the cells which elaborate the poison, and from which it escapes, by the rupture of the cells, into the central cavity of the organ. Physiologically, this poison is very active, and that in direct relation to the quantity introduced ; one drop is soon fatal to a rabbit, and still more active on a bird ; seven to eight frogs may be killed by one drop, and the hundredth part of one is fatal to an ant of large size. It would appear to affect the nervous system, and has undoubt- edly a marked action on striated muscle, suppressing spontaneous and reflex movement. Snares of Orb-weaving Spiders.t—The Rev. H. C. McCook, ac- cepting Thorell’s arrangement of the true spiders into Sedentary (remaining for the most part in or upon their web and capturing their prey by means of snares), and the Wandering (hunting their food on the ground, the water, or trees), applies this principle of arrange- ment according to economy to the first section of the Sedentary Spiders—the Orb-weavers—which, whether “ simply tentative, and in its present form incomplete, is given with the hope that it may lead to * Comptes Rendus, xev. (1882) pp. 866-9. + Proc. Acad. Nat. Sci, Philad., 1882, pp. 254-7 (1 fig.). 56 SUMMARY OF CURRENT RESEARCHES RELATING TO something better, by fixing the attention of the very few students of our spider-fauna, among whom no such grouping has hitherto been proposed. Moreover, it is hoped that the arrangement may have some interest to naturalists generally as bearing upon the corre- spondence between structure and economy and the value of habit as a factor in classification.” An orb-web may be defined as a series of right lines radiating from a common centre, and crossed at intervals by other right lines attached at the point of contact and covered by viscid beads. Orb- webs are divided generally into vertical snares and horizontal snares, according as they are perpendicular to, or parallel with, the plane of the horizon. The vertical snares the author divides into (1) full orbs, (2) sectoral orb, (3) actinic orb, and (4) orb sector; the horizontal snares into (5) plane orb, and (6) domed orb. A table of these divisions is given, with sections and subsections, the former being mainly founded upon the character of the snare, as “ simple” or “compound,” and the latter being for the most part determined by the “hub” (the small open or meshed circle upon which the radii meet), which may be open, meshed, notched, &e. Swiss Hydrachnide.*—Dr. G. Haller gives an account of the Hydrachnide found in Switzerland, with descriptions of twelve genera, including one new genus (Forelia, dedicated to Prof. Forel of Morges) and three new species. 5. Crustacea. Homologies of the Crustacean Limb.t—Dr. A. 8. Packard, jun., commences by pointing out that, if we make a section of a typical Phyllopod, e. g. Apus, we see that the apparent bulk of the body is mostly due to the large size and nature of the foliaceous appendages ; these have broad attachments, altogether different to the small anal articulations with which we are all familiar in the crayfish. The appendages of Crustacea may be grouped under four heads: they are sensory (pre-oral), masticatory (post-oral), locomotor (thoracic), or natatorial and reproductive (abdominal). In a table the author gives an arrangement of the appendages in the three sub-classes of Tracheata, and the two sub-classes of Branchiata. The antennz of the Hexapoda are looked upon as the homologues of the mandible of the Arachnida, and the first pair of legs of the Merostomata; the second pair of antenne in the Crustacea as homologous with the mandibles of Hexapods, the “ chela” of Arachnids, and the “ maxilla” of Myriopods. The Cladocerous limb is thought to be intermediate between the Phyllopodous and Ostracodous limbs, and an ascending series may be seen from the Copepoda to the Ostracoda, and thence to the Phyllopoda. Hence, as the young of the Copepoda are all nauplii, and also those of the Phyllopoda, it follows that the ancestral form of all the Entomostracous Crustacea, as originally insisted on b F, Miiller, was a nauplius-like animal. The characters of the Decapod * MT. Naturforsch. Gesell. Bern., 1882, Abhandl. pp. 18-83 (4 pls.). + Amer. Nat., xvi. (1882) pp. 785-99 (2 pls.). ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 57 limb are so different to those of the Phyllopod as to lead to the view that the Decapoda have risen from the nauplius independently of the Phyllopoda ; and it would appear that the entire leg of the Phyl- lopod (without the gill and flabellum) is homologous with the endo- podite of the Decapod maxilliped and the gill and flabellum with those of the Decapoda. The appendages of Limulus may be brought into relation with those of other Crustacea by appending an exopodite to the coxopodite, and arranging the gills on the outer side of a more or less cylindrical epipodite, instead of having them set antero-poste- riorly. The ‘author insists that radical changes of structure and changes in function may be seen in the Malacostraca, and he argues that still greater modifications may have obtained in the Paleocarides, of which Limulus is the sole survivor. The resemblances to the Arachnida are looked upon as merely analogous, and it is urged that the synthetic characters of Limulus may be shown to be very striking when a longitudinal section of it is compared with one of Apus; there may be seen such resemblances as the lobules of the liver filling the front part of the head, the oblique, long, narrow cesophagus, the position of the stomach under the eye, the simple archi-cerebrum, the general form of the heart, and the “ gnathobases ” near the mouth. Characters of Nebalia.*—Dr. Packard also gives an account of the structure of Nebalia, a form which is of particular interest from “its composite nature,” and its relation to some fossils which are generally regarded as Phyllopods. After an examination of the appendages the author points out that there is only a general homo- logy between the thin, lamellar, thoracic foot of Nebalia and that of any Decapod; when the thoracic legs of the adult Nebalia are com- pared with the maxillipedes of the zoéa of the Decapods, a slight and interesting resemblance may be detected, but not so close a homology as between the maxille of the zoéa and the thoracic legs of the Phyllopods. In fine, the resemblances are so slight that we are forced to confess that Nebalia is not a Decapod. The form is, further, distinguished by the absence of a telson. During the history of its development the diagnostic ordinal characters of the Phyllocarida declare themselves: the large movable rostrum, the compressed pseudobivalvular carapace, the lack of maxillipedes, the eight pseudophyllopod thoracic feet, and four pairs of abdominal feet, out of the six of the adult. Mysis does not seem to be descended from a Nebalioid, but from a zoéa-form. The Phyllocarida have had no Decapod blood in them, so to speak, but have descended by a separate line from Copepod-like ancestors, and culminated and even began to disappear before any Malacostraca, at least in any numbers, appeared. Nervous System of Palemonetes varians.j—A. Garbini describes the different parts of the nervous system and the sense-organs. Of especial interest are certain bodies found on the endopodites of the * Amer. Nat., xvi. (1882) pp. 861-73 (3 pls.). + Atti Soc. Veneto-Trentina, vii. (1882) (6 pls.). Cf. Bull. Soc. Entomol. Ttal., xiv. (1882) p. 250. p 58 SUMMARY OF CURRENT RESEARCHES RELATING TO antenne where the tactile rods are placed in many Crustacea. They not improbably have an olfactory function here. New Genus and Species of Lyncodaphnide.*—Mr. C. L. Herrick describes Lyncodaphnia macrothroides from Lake Minnetonka, Minne- sota, the form of which is much as in species of Alonella, &c.: truncate behind; superior antenne like Macrothrix, attached movably to the end of a blunt prominence beneath the head; second or swim- ming antenne slender, four-jointed ramus with three long sete and a stout thorn at the end of distal segment, the joint following the short basal one with a thorn above, the following joint unarmed ; three-jointed ramus as in Macrothrix, the basal segment armed with a much-elongated seta; eye relatively small, pigment-fleck (macula nigra) present ; intestine twice convoluted, expanded in front of the rectum, opening in the “heel” of the post-abdomen; post-abdomen slender, subtriangular, margined behind with a double series of spines; terminal claws large, and furnished with a long and short spine near the base ; shell margined below by stout movable spines. Few more interesting forms than the one forming the type of this very peculiar genus have been found, since it combines in a curious manner those characteristics hitherto regarded as distinctive of the families Daphnide and Lynceide. Kurz says, “ Keine Cladoceren- familie bildet eine so streng in sich abgegrenztes natiirliches Ganze, wie eben die Lynceiden,” and this after recognizing the relationship of Macrothrix and Lathonura to the Lynceids, by placing them in the subfamily Lyncodaphnide. The form above referred to, however, has quite as close affinity to the Lynceide as to Macrothrix, though it resembles the latter rather more on a superficial examination; indeed, if one were to divide the animal back of the heart and examine the two portions independently, it would be impossible to avoid referring the head to Macrothrix and the body to some Lynceid genus. Thus is furnished another of those curious intermediate forms which remind us that the possibility of distinguishing families and genera, lies alone in the meagreness of our knowledge. There can be no doubt that this genus should stand next to Macrothriz, but it will be necessary to modify a little the diagnosis of the Lyncodaphnide to receive it, and it then appears that it cannot longer remain a subfamily of the Daphnidz, hence Mr. Herrick proposed to give it equal rank with that body and the Lynceids as an independent family, Lyncodaphnide, including the genera Macrothria, Lyncodaphnia, Drepanothrix, Lathonura (= Pasithea), Ilyocryptus. As thus limited a very natural group is formed, in size and isolation corresponding well with the other related families. Vermes. Tubes of Sabellide.t—E. Macé, struck by the great diversity of these structures in so homogeneous a group as the tubicolous * Amer. Natural., xvi. (1882) pp. 1006-7 (1 pl.). + ‘Dodekas neuer Cladoceren nebst einem kurzen Uebersicht der Cladoceren- fauna Bohmens,’ p. 30. t Arch. Zool. Expér. et Gén., x. (1882) pp. ix-xiv. a ake — ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 59 Annelids, has endeavoured to detect signs of a fundamentally iden- tical structure. The tube of Sabella penicillus is formed of two parts, different in origin and in function ; the former, which is external and accessory, is not secreted by the animal, but obtained from the sur- rounding medium; the other, which is essential and constant, is made by the Annelid; this is the tube proper. The very varying characters of the former are to be explained by the great differences in the nature of the surrounding medium, and this part of the tube may differ considerably in its different regions. When the materials for forming it are too large to be seized by the cirri the mucous portion is much thicker ; at the same time it is to be observed that the animal economizes as much as possible its own secretion. ‘The outer portion is very distinctly annulated transversely, apparently in corre- spondence with the segmentation of the Sabella; though it cleaves easily in all directions, it does not, owing to the structure of the inner layer, fall to pieces. This inner layer is formed of a colourless hyaline substance, which swells considerably when macerated in water, and becomes hard and brittle by drying. During life it is perfectly flexible and very resistent. Sections are most conveniently studied in salt solution, as glycerine makes them too transparent. They are not modified in structure by the action of alcohol. A transverse section reveals the presence of concentric strata of some thickness; these may be broken up into very fine fibrils which swell, and rapidly become invisible under the action of reagents. On the inner side there is a very delicate granular layer, easily coloured by carmine. After macera- tion in water, an external and an internal membrane can be made out ; these form a kind of sheath or cuticle, which resists the reagents which affect the median zone. The outer one is formed by large irregular plexuses, the bands of which have a fibrillar structure; the inner layer is continuous and is made up of excessively fine fibrils, crossing one another, but the majority have a longitudinal direction; among them there may be seen a large number of small hyaline rod-shaped bodies, similar to the so-called tactile organs which have been found in the integument of Vermes. The author compares this arrangement with the nematocysts found in the tube of Cerianthus by Haime. The greater part of the tube is formed by the median zone; the layers, of which it is composed, vary in number and size pro- portionately with the thickness of the layer; the bundles which make it up give off anastomoses and prolongations, which traverse the spaces in the plexus of the outer zone. Chemical structures show that it is formed by an albuminoid substance, very near to, if not the same as, mucin, and it appears to be secreted by special glands which lie at the base of the branchial cirri. The calcareous part of the tube of Serpula is regarded as the homologue of the mucous part of the tube of Sabella. North-Sea Annelids.*—G. A. Hansen, in Norwegian and English (in parallel columns), gives an account of the Annelids collected by * 4to, Christiania, 1882, 53 pp. (7 pls., 1 map). 60 SUMMARY OF CURRENT RESEARCHES RELATING TO the Norwegian North Sea Expedition of 1876-78. He criticizes Malmgren’s method of distinguishing and delimiting genera, of which he thinks he has made far too many and has used altogether unimportant characters; he points out that the pedal bristles do not differ in essential matters—* the type of the bristles is the same in all Polynoe, with the exception of Melenis loveni and Polynoe scolopen- drina.” The scales, in Hansen’s opinion, are much more valuable, being characteristically constant in each species, and a study of them shows that Mébius and Tauber have gone too far in the opposite direction of “lumping” Malmgren’s species and genera. Tables of distribution are given from which it is evident that but few families of Annelids are absent from the frigid area, and the species are the same as those found in temperate waters; P. globifera alone indicates that its favourite,.if not its sole, habitat is the cold bottom strata. As it is both coloured and provided with eyes it throws much doubt on the hypothesis of Ehlers that the deep-sea fauna has its numbers recruited from forms living in shallower water. Neither depth nor temperature appear to affect the development of Annelids. A number of new species are described. Eclipidrilide.*—G. Eisen gives an account of a new Oligochete which he discovered in 1878 in the Sierra Nevada ; the specimens that he took down with him dying before he reached a Microscope, he scaled the mountains again in the succeeding year, so as to be able to make an investigation into the characters of its circulatory system on the spot. The vascular system consists of two primary longitudinal vessels, of which the dorsal pulsates and is of nearly the same size as the ventral; there are secondary perigastric and gastric vessels, and the former are either connecting or free. The former of these are found in the anterior segments of the body, and connect the two primary vessels ; the two last are longer than the rest, and supply the generative organs; they are none of them dilated into hearts, but they all pulsate slightly. The free perigastric vessels are placed in the more posterior segments, and are derived from the dorsal vessel; they pulsate slightly, and their inner end is free. The gastric vessels are found in the segments in which there are no perigastrics, and connect the dorsal and ventral vessels. Resembling, therefore, on the whole the vascular system of Tubificide and Lumbriculide, that of the Eclipidrilide is distinguished by never having gastric and perigastric vessels in the same segment. The blood is of a reddish yellow colour. The digestive system is a simple duct, just as in the Tubificide. The testes form two saccular amorphous bodies in the 9th-13th segments, one on each side of the body ; they contain numerous cysts of spermatozoa, but no free ones, and each cyst forms a globular body, with a round wedge-shaped tail; it is always covered by globules, which are either partly separate, or which run together forming beautifully elevated ridges, which in regularity and beauty can only * Nova Acta Reg. Soc. Upsal., xi. (1881) 10 pp. (2 pls.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 61 be compared to the skeletons of certain diatoms. There are three pairs of very small ovaries, placed in the 3rd, 9th, and 10th segments ; the oviducts appear to be represented by two very minute and delicate organs in the 9th segment ; they are funnel-shaped, and the globular internal orifice is devoid of cilia. The efferent ducts are of enormous size, and each consists of two saccular ducts of nearly equal size, connected at the extremities by a short narrow tube, which is sur- rounded by spiral muscles; the longer of the two is the one which is directly connected with the body-wall, and it has near its inner end three very minute circular orifices. Inside this duct there is another, which is always full of spermatozoa, and evidently serves as a true seminal vesicle. “The total absence of efferent funnels is a character- istic of great value, not met with anywhere else in this class of worms, and which places Hclipidrilus in its decidedly isolated position.” The single known species is called H. fragidus, and has only as yet been found in the high Sierra Nevada of California at 10,000 ft. or higher. It is a true limicolide Oligochete, with its closest relations with the Tubificide and Lumbriculide. Ctenodrilus pardalis.*—J. Kennel, after a description of the external form of this Annelid, in which he directs attention to the variations in the arrangement of the sete, describes the histological characters; the central nervous system, throughout its whole length, lies in the epidermis, and exhibits the very simplest arrangements, comparable more to what is seen in Polygordius and Saccocirrus than in any higher form. The supra-cesophageal ganglion is formed by a transverse bridge of fine dotted substance, in which no fibrous bands are to be detected, and of surrounding ganglionic cells, which are collected into two lateral groups, without, however, being sharply separated off from the epithelial cells. On either side, the dotted substance of the ganglion is continued into a fine commissure which traverses the epidermis and becomes connected with the ventral medulla; these bands appear to be devoid of any ganglionic invest- ment. The ventral cord presents very much the same histological characters as the dorsal ganglia, for, just below the basal membrane of the epithelium, there is a fairly well developed cord of dotted sub- stance, with cells at its sides, which pass without any distinct demar- cation into the epidermal cells, between which and them no absolute difference can be said to exist. No peripheral nerves were detected, but, though their absence is not to be assumed, there would appear to be no absolute necessity for their existence ; inasmuch as it is pro- bable that here, as in many of the lower animals, the elements which form the tissues have many of the properties belonging to a simple living cell, and, among these, irritability. The only sensory organs are the two small ciliated pits which are placed at the sides of the cephalic lobe, on the dorsal ganglion ; their depression is very shallow, and only a few cells take part in their formation. Similarly, a great simplicity is to be seen in the musculature; immediately below the fine basal membrane of the epidermis there is * Arbeit. Zool.-Zoot. Inst. Wiirzburg, v. (1882) pp. 373-429 (1 pl.). 62 SUMMARY OF CURRENT RESEARCHES RELATING TO a single layer of longitudinal muscular fibres, which are not divided into arew, though they are found at regular distances all around the animal. The mesodermal tissue between the musculature and the enteron is, likewise, very slightly developed ; in connection with the peritoneum there is a thin layer of small cells in which gemmation may be seen; this, which may be looked upon as undifferentiated mesoderm, is most largely developed in the region of the dissepiments. The stomach and intestine are formed by a single layer of large epithelial cells; all the cells of the intestine are ciliated. The circu- latory system is not closed, and presents a greater simplicity than that known in any other Annelid; a thin membrane, with scattered spindle-shaped nuclei, forms the wall, and has no thickenings or additions even in the dorsal contractile portion; on the other hand, we find in this dorsal vessel a solid cord of cells, the function of which must remain very obscure, unless we are allowed to regard it as a hematopoetic organ ; it may be compared with the structure noted by Claparéde in Terebella. There is but one pair of segmental organs, lying directly behind the pharynx, and, as it seems, in the first, or, at least, in the second segment. Their walls are extraordinarily thin, and their lumen of pretty much the same width throughout. The account that has been given will be sufficient to show that in Ctenodrilus we have to do with an ancient and “collective” type which exhibits affinities to the Oligocheta on the one hand, and the Polycheta on the other; the very forward position of the segmental organs forbids us to look upon it as a degraded form. For its reception there may be formed a family Ctenodrilide, consisting of small marine Annelids, of a few segments, with two pairs of set#, a non-closed blood-vascular system, the dorsal vessel lying in the first body- segments, and opening into the ccelom in the first trunk-segment. A single pair of segmental organs in the head. Reproduction by division with gemmation. Sexual reproduction unknown. Ctenodrilus and Parthenope the two known genera. The rest of the paper is occupied by an account of the phenomena of gemmation. Distichopus.*—Prof. J. Leidy describes a new genus of Annelids— Distichopus, closely allied to Enchytreus, but with setapeds in a single row on each side ventrally, and not double as in the former genus. Turriform Constructions by Earth-worms,t—In his work on worms, Darwin has described some tower-like dejections which he never saw constructed in England, but which are attributed to an exotic species of Pericheta from Eastern Asia, naturalized in the environs of Nice. E. L. Trouessart has lately observed similar dejec- tions in gardens near Angiers. Having collected a large number of worms from where the towers were made, he found no species of Pericheta, nor of any other exotic genus. In two or three cases he surprised the worms at work, and they were Lumbricus agricola, * Proc. Acad. Nat, Sci. Philad., 1882, pp. 145-6, + Comptes Rendus, xcy, (1882) p. 739. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 63 It was the anterior part of the body that was lodged in the tower. After the rainy period at the end of September all the tubular interior of each tower (forming a continuation of the subterranean gallery) was quite free ; but a few days later it was obstructed by recent de- jections. M. Trouessart supposes that the calotte or cap of the tower, getting hard in air, a time comes when the worm can no longer burst the upper wall as before, to place its dejections outside (so increasing the height of the tower), but deposits them within. Thus a long period of rain is necessary for these towers to rise regularly. The towers probably serve to protect the galleries from rain, and to afford a breathing place for the worms, where they are not seen by birds. Hamingia arctica.*—This remarkable Gephyrean was first de- scribed by Koren and Danielssen + from a spirit specimen, and subsequently by Dr. Horst { from two sent to him. Prof. E. Ray Lankester having obtained a fresh specimen as well as one in spirit, is able to add to our knowledge of its character. He finds it is really intermediate in its combination of characters between Bonellia and Thalassema. Owing to their not having known the frontal hood or proboscis, Koren and Danielssen somewhat over-estimated the closeness of its relationship to Bonellia. On the whole it may be said that Hamingia has in internal organs a closer resemblance to Bonellia, but in external shape and characters a closer resemblance to Thalassema. 'The feature in which it is quite peculiar is the absence of genital sete in the female and the correlated existence of one or of two prominent papille which carry the genital pore or pores. The new facts recorded, additional to the observations of Koren and Danielssen and Horst, are briefly as follows :— 1. Hamingia arctica occurs on the Norwegian coast in latitude 60°, and at the comparatively small depth of 40 fathoms. 2. It has a frontal hood or proboscis resembling that of Thalassema, which is easily broken off, as in Thalassema and EHchiurus. 3. The corpuscles of the perivisceral fluid are coloured by hemoglobin. 4, The male (five of which, 1-12th in. long, were found within the dilated pharynx of the female) is a diminutive parasite living upon the female, as in the case of Bonellia ; it is provided with a pair of large genital sete, although such sete are absent in the female. 5. Though usually there are two, yet there may be only one uterus, and one genital pore, as in Bonellia. Anatomy of Prorhynchus.§—J. v. Keunel discovered specimens of Prorhynchus in the neighbourhood of Wirzburg, and has also examined examples from other localities. Unlike M. Schultze, who regarded it as a Nemertine, v. Keunel looks on this genus as belonging to the Rhabdoccela; the first point in favour of this view is the character of the digestive tract; the mouth lies at the most anterior end of the * Ann. and Mag. Nat. Hist., xi. (1883) pp. 37-48 (2 figs.). + Cf. this Journal, i. (1881) pp. 45, 890. t Ibid., p. 891, and ii. (1882) p. 50. § Arbeit. Zool.-Zoot. Inst. Wiirzburg, vi. (1882) pp. 69-90 (1 pl.). 64 SUMMARY OF CURRENT RESEARCHES RELATING TO body, and, in life, is a circular orifice largely capable of extension and contraction. The cesophagus is narrow and thin-walled; the pharynx, which is strongly muscular, may be elongated or shortened, or pro- truded through the mouth ; in histological characters it agrees gene- rally with the same organ in many Rhabdoceeles, e. g. Derostomum. The intestine makes but feeble curves, and ends blindly at the hinder end of the body. No less do the other characters—external covering, musculature, and so-called body-parenchyma—tell the same story of zoological affinity. The ciliated body-epithelium is composed of polygonal flattened cells, with finely dentated margins. Below this there is a single layer of longitudinal fibres, and then one of circular fibres, which is likewise single; none of the fibres have a nucleus, and they are all very long and fine. The parenchyma is very feebly developed on the hinder part of the body, or region of the true intestine ; anteriorly it presents a cellular structure with a number of nuclei, and between these, especially in the most anterior region, there are large vesicular spaces, which permit of the contractions of the body and the protrusion of the cesophagus, and copulatory organ. The body- wall appears to be remarkable from being traversed by numerous efferent ducts from small unicellular glands, which lie within the musculature, and are to be regarded as modified epidermal cells; they are perhaps homologous with the rod-cells of other Turbellaria. The nervous system is in every way that of a typical Turbellarian ; the cerebrum lies in front of the pharynx, above the cesophagus; it consists of three ganglia, which are not sharply separated from one another; one is median to the other two. The latter give off two longitudinal nerves, which are altogether devoid of ganglionic cells, and which very soon become thin ; they probably reach to the hinder end of the animal. All these ganglia give off groups of ganglionic cells anteriorly ; the dorsal series extend almost to the anterior end of the body, while the lateral pass to the lateral pits of the head. The brain of Prorhynchus is, then, to be distinguished only from that of other Rhabdoccela by the fact that the commissure is covered by ganglionic cells. The first-mentioned pits have a narrow orifice and are somewhat pyriform in shape; the longer cilia which invest them are placed on a fringe formed by fused epithelial cells. Such pits are known in certain Rhabdoceles, e. g. Microstomum and Stenostomum, &c. Although Prorhynchus, like the majority of known Rhabdoceela, is hermaphrodite, there is some reason for supposing that the male are mature before the female products ; the male organs consist of a pro- trusible penis, connected with a ductus ejaculatorius, which, after coils that vary with the state of contraction of the animal, passes to a thin-walled seminal vesicle; the whole apparatus is ventral in position, and ought not, therefore, fora moment to be compared to the pro- boscis of the Nemertinea; the male glands lie behind the vesicle, on either side of the intestine, where they have the form of small rounded follicles, without special walls ; they are filled with finely granular cells of various sizes, intermixed with ripe spermatozoa. The larger of the cells often contain two nuclei, and are peripheral in position; the smaller ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 65 cells are the products of their division. The female germ-gland forms a band-shaped organ, which lies beneath the intestine, and consists at its hindermost end of indifferent, and at its anterior end of ovarian, cells. The female orifice lies in the ventral median line, and there is a feebly developed vagina, with which are connected some glandular cells. The female organs are, on the whole, as much of the type of those of other Rhabdoccela as are the male. The excretory system opens, at the level of the female pore, on either side of the body; connected with this is a short terminal canal: with firm contractile walls. For other points reference is made to the accounts o* earlier observers. The paper concludes with the description of P. balticus n. sp. Monograph on the Turbellarians.*—Prof. L. von Graff has pub- lished a splendid monograph of this group, founded on elaborate personal investigations. Separating the Nemertines altogether from the Turbellarians, he divides the group into I. Rhabdoccelida, and II. Dendroccelida. In the definition given of the two sub-orders, an interesting point of difference is brought out, namely, that in the former the yolk-glands are always present in the form of a pair of compact glands, whereas in the latter they are always divided up into numerous separate follicles. The Rhabdoccelida are divided into three groups :—(1) Accela ; (2) Rhabdoccela ; (3) Alloioccela, which are thus defined :— (1) Accela. With digestive internal substance ; without differen- tiation of a digestive tract and parenchym tissue. Without nervous system or excretory organs. All forms as yet known provided with an otolith. (2) Rhabdoccela.—Digestive tract and parenchym tissue differ- entiated ; a roomy body-cavity usually present, in which the regularly shaped intestine is suspended by a small amount of parenchym tissue. With nervous system and excretory organ. Generative organs hermaphrodite (except in Microstoma and Stenostoma). Testes, as a rule, two compact glands. The female glands present as ovaries only, ovario-vitelligenous glands, or separate ovaries and yolk-glands. Genital glands separated from the body parenchym by a special tunica propria. Pharynx always present and very variously con- structed. Otolith absent in most cases. (3) Alloioccela.—Digestive tract and parenchym tissue differ- entiated, but the body-cavity much reduced by the abundant de- velopment of the latter. With nerve system and excretory organ. Generative organs hermaphrodite, with follicular tests and paired female glands, either ovaries only, or ovario-vitelligenous glands, or separate ovaries and yolk-glands. Yolk-glands irregularly lobular, rarely partially branched. Genital glands almost always without any tunica propria lodged in the spaces in the body parenchym. Penis very uniform, and either without chitinous copulatory organs, or with * Graff, L. von, ‘Monographie der Turbellarien. 1. Rhabdoccelida.’ Fol. Leipzig, 1882, 12 figs. and 20 pls. Cf. Prof. H. N. Moseley in ‘Nature,’ xxvii. (1883) pp. 227-8. Ser, 2.—Vot. III. EF 66 SUMMARY OF CURRENT RESEARCHES RELATING TO these very little developed. Pharynx a pharynx variabilis or plicatus. Digestive tract lobular, or irregularly broadened out. All marine except one, or possibly two species. (Under the Alloioccela come the genera Plagiostoma, Vorticeros, Monotus, and others.) The work commences with a complete list of the literature on Turbellarians from the time of Trembley, who, in 1744, figured a black fresh-water Planarian, to that of the publication of the last of Dr. Arnold Lang’s important memoirs last year. The list is followed ‘by a general treatise on the anatomy and physiology of the Rhabdocos- lida. The account of the nematocysts of some forms is very interesting ; their exact resemblance to those of Ccelenterata is fully borne out. Microstomum lineare appears to be the only species which, like Hydra and Cordylophora, possesses two kinds of nematocysts. The author thinks he has been abfe to detect on the surface of the cuticle, trigger hairs in connection with the nematocysts, like those in Hydroids. He considers the rhabdites or rod-bodies homologous with nematocysts, and refers, in connection with this question, to the nematocysts devoid of any thread which occur in many Ccelenterates, intermingled with fully developed ones. The structure of the pharynx is carefully gone into, and its different forms being of much use in classification, receive various names, such as Pharynx bulbosus, P. plicatilis, &e. The water-vascular system has been studied by von Graff with considerable success. It may consist of a single median canal with a single posterior opening (Stenostoma), or a pair of laterally placed canals with a similar single opening or two separate lateral canals with each a posterior opening (Derostoma), or there may be a pair of openings or a single one somewhat anteriorly placed. Ciliated funnel cells or flame cells, such as exist in Cestodes, Trematodes, and Triclad Dendroceeles, have been discovered by von Graff also in the Rhab- doccelida. ‘They do not, however, occur in connection with the tips of the ramifications of the water-vascular canals, but almost entirely on the larger canals forming the networks. It is impossible here to follow the work further, through the interesting sections devoted to the development of Microstoma by budding, and the habits of life and distribution of the Rhabdoccelida. In connection with the discussion on classification, a table of the pedigree of Turbellaria is given, with Proporus as the ancestral starting-point. In this family tree the Dendrocceles are shown as derived from Acmostoma, a new genus of Alloiocela, characterized by having a distinctly marked narrow ambulacral sole, the Polyclades directly, and the Triclades through Plagiostoma. The ascertained facts as to the structure of Turbellarians seem to point even more closely to their connection with the Celen- terata. The presence of two kinds of nematocysts in one of the Rhabdoccela, and the possible occurrence in members of that group of trigger hairs, is a remarkable fact. Dr. Lang, believing that a part of the nervous system in Dendrocceles is truly mesenchymatous, as in Ctenophora, and from other grounds, concludes with Kowalewsky that the Polyclada are “creeping Colenterates which have many points of structure in common with the Ctenophora, some with the Meduse.” Such being the case, naturalists wait with great impatience ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 67 Kowalewsky’s promised further information as to his extraordinary Celoplana, supposed to be intermediate between Ctenophora and. Dendroceelida. The peculiar azygos character of the otolith in so many Dendroccelida may perhaps be explained by the similar con- dition of the sense-organ in Cceloplana. Whether the second part of the work, dealing with the Dendro- coelida, will be published or not depends upon the extent to which Dr. A. Lang’s forthcoming work may cover the same ground. Dinophilus apatris.*—EH. Korschelt gives a full description of this new species of Turbellarian. After a short account of the known species, and the characters of the new one, as drawn from the female, he describes its habits, as observed in a marine aquarium. The body is covered by an epidermis, which consists of a layer of irregular polygonal cells; there would appear to be no rods, but, more especially in the young, we may see a number of small rounded bodies, which have the same refractive index, and possibly are comparable to them. From these cells there arise cilia, some of which are shorter than the others; the former are arranged in eight regular rings, and of the latter two well-marked pairs are to be seen at the anterior end of the head, with others on the tail and on the dorsal surface. From their position we may justly assume their tactile function. The expression body-space is expressly used for the purpose of marking the difference between it and the body-cavity of the “ Entero- celia”; itis a wide cavity, such as is seen in no other Turbellarian, and is traversed by only a few very fine connective bands, which arise from the body-wall and are inserted into the intestine; in the head these are more numerous and completely fill up its anterior portion ; the same is to be observed in the tail. Notwithstanding its apparent differences it has really a very close resemblance to the ccelom of other Platyhelminths. The ventral mouth forms a three-rayed cleft, placed near the anterior end ; it is extraordinarily extensile, on account, probably, of the great size of the protrusible proboscis; the pharynx forms a wide, richly ciliated cavity, and leads into the strong-walled crop; on either side lies a racemose “ salivary” gland. The stomach only opens to admit the nutrient balls, formed in the crop, and is much less strongly ciliated than the parts in front of it. The rectum and anus are richly ciliated. The proboscis consists of a solid, not hollow, mass, and lies beneath the crop; it is angulated in the middle, and so appears to consist of two halves; the anterior portion is completely devoid of muscles, but in the hinder we find circular fibres which are distinctly striated, and below them a layer of less well developed longitudinal fibres. The author agrees with Hallez in thinking that the function of this organ is to brush the surface of plants to detach débris and diatoms, and that it does not, as in some Turbellaria, seize on living animals. The eyes are well developed, and behind them, especially in * Zeitschy. f. Wiss. Zool., xxxvii, (1882) pp. 315-53 (2 pls.). - F 2 68 SUMMARY OF CURRENT RESEAROHES RELATING TO young transparent forms, there is a dark body, whence two trunks proceed forwards to the eyes, and two, which may be considered as the roots of the longitudinal trunks, pass backwards; elongated ciliated clefts, sometimes observable behind the second ciliated ring, probably correspond to the ciliated pits which have been noted in other species of this genus by Schmidt and Hallez. With a high power cilia in action may be detected at various points of the body, and here and there we may see a plexus of clear, extremely fine canals, whicb, after some continued pressure on the cover-glass, may be made out over the whole body; the primary canals appear to be represented by wider ducts, which were most often detected in the hinder parts of the body, and near the ovary an orifice was seen on the ventral surface. After describing the generative organs, and pointing out the lower organization of the male, and its shorter existence, which would seem to be in correlation with this, Korschelt passes to the developmental history ; in the ova there were two polar globules ; cleavage does not commence for some time after deposition, and is unequal ; the smaller sphere then divides equally, and then a smaller sphere is separated off from the larger one. The large one then divides equally, and one of these breaks up again. Later on, the large sphere again divides, and the two are gradually overgrown by the smaller cells. The two endoblastic, as well as the ectoblastic cells present pseudo- podial processes, and it is not for some time that cilia become developed. Later on, the eggs become very opaque. As to its systematic position, the author finds that Dinophilus has most resemblance to the Turbellaria, but it is remarkable for the indications of segmentation, the arrangement of the cilia, the proc- tuchous enteron, the position of the proboscis behind the mouth, and the structure of the generative organs; a new family must at least, be formed for it. Life-History of the Liver Fluke.*—Prof. A. P. Thomas under- took an investigation of this subject at the request of the late Professor Rolleston on behalf of the Royal Agricultural Society. The ravages made by the liver fluke have been very great (as many as 8,000,000 sheep being lost by it in this country in the year 1879- 80), and the search for the intermediate host had previously been futile. Mr. Thomas thoroughly searched meadows for every species of mollusc likely to be an intermediary host, dissecting them without success, until at length he succeeded in finding in the small Limneus truncatulus, a cylindrical Rédia, containing cercarie. The cercaria is of tadpole shape, and has the peculiar habit of encysting itself directly it is brought into contact with any solid object, the material for encystation being exuded from some lateral masses in the body of the larva. For some time the inquiry was arrested because of the author’s inability to find any more specimens of the Limneus, even where they had abounded in the previous year. In July last, how- ever, after floods, he found an ample supply. The snail in question is more truly amphibious than a water-snail, is very small—about * Quart. Journ. Mier. Sci., xxiii. (1883) pp. 99-133 (2 pls.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 69 1-4th in. long—and wandering along the damp roots of grass, its presence may readily be overlooked. The infection experiments proved that this mollusc was the sole intermediary host of the fluke. The fluke is very prolific, but so long as the ova remain in the liver they undergo no further change. In artificially hatching them, the embryo is seen to leave the egg by the sudden giving way of the operculum ; and once in water the cilia with which the body of the embryo is covered come into action. The free-swimming embryo has a spindle shape and is provided with a double eye spot (two masses of pigment), and is very sensitive to light. If the embryo comes in contact with a Limneus truncatulus it begins to bore into its shell, the head papilla becomes elongated and sharp, and by a sudden movement the boring is effected, and the body of the embryo passes into the snail. As soon as it gets into the snail the body contracts, its outer layer is cast off, and it degenerates into a sporocyst. By proliferation of cells lining the body-cavity and of cells in the body-walls, masses of germinal cells are formed from which the cercaria is developed. The sporocyst usually developes in the pulmonary cavities of the snail and the parasite gets into the liver, feeding on the liver cells. The cercaria is formed by the rounded germ-masses becoming elongated, one end being pinched off to form a tail, When the cercaria has escaped and become encysted, if remains quiescent until swallowed by the sheep; when, the cyst being dissolved, the embryo fluke finds its way into the liver ducts of the sheep. The real preventive of the disease is salt, a small quantity of which will not only kill the larve of the fluke, but the Limneus also. The salt should be scattered over all land where the snail is believed to be present. Ankylostoma and Dochmius.*—P. Méenin, in examining a number of dogs attacked by the anemia which decimates large numbers annually in France, found that three apparently different species were always present. One in which the buccal armature has straight teeth answering to Dochmius trigonocephalus of Dujardin ; another with hooked teeth like Ankylostoma duodenale of Dubini, which has pre- viously only been found in man; and a third with hooked teeth, within the inner pair of which is a small tubercle like Dochmius balsami of Grassi = D. tubeformis of Dujardin. As these three forms are constantly found living side by side in the same host and contributing to the same disease, the author con- siders that they represent one species in which the form of the teeth probably varies more or less with age. New Floscularie.—Dr. C. T. Hudson announces the discovery by Mr. J. Hood of Dundee, of a very large and strange Floscule, new to science, which he names F’. Hoodii after its discoverer. It is no less than 1-10th of an inch in length, and is therefore by far the greatest of all the Rotifera, exceeding F. trifolium as much as that does F. campanulata. It has only three lobes, very short set, a very peculiar outline to its trochal disk, and, strange to say, two * Bull. Soc. Zool. France, vii. (1882) pp. 282-9. 70 SUMMARY OF CURRENT RESEARCHES RELATING TO large conical hollow processes protruding one on each side of the anterior portion of the dorsal surface—perched right on the prominent dorsal lobe. Dr. Hudson will figure and describe this new rotifer in the April number of this Journal, together with another new species, also dis- covered by Mr. Hood, F. longicaudata ; the latter has its footstalk ending in a very long non-retractile pedicle, and forms also a peculiar tube. Echinodermata. ‘Challenger’ Holothuroidea.*—The first part of H. Théel’s Report on the ‘Challenger’ Holothuroidea is devoted to the new order Elasipoda, which name has with advantage been sub- stituted for that of Elasmopoda, used in the Preliminary Report. Seven years have scarcely elapsed since the discovery in the Kara Sea of the form for which this family was established, and now over fifty species are known. These species of Hlasipods are true deep-water forms, and they may with all the more reason be said to characterize the abyssal fauna, as no single representative, as far as is at present known, has been found to exist at a depth less than 58 fathoms. Only one form, Elpidia glacialis, has been dredged at such an inconsiderable depth, and even this was dredged in the Arctic Ocean, where true abyssal forms are to be met with at comparatively shallow depths. This species, too, can exist at immense depths, one from Station 160 having been dredged at a depth of 2600 fathoms; the greatest depth at which any Holothuroid has hitherto been dredged being 2900 fathoms. Among the more remarkable and distinguishing characteristics of this order, Herr Théel mentions the agreement in several important details—both in their internal anatomy and outer form—of the adult and larval states; an agreement more close than occurs in any pre- viously known Holothuroid. He does not agree with Danielssen and Koren in placing the Elasipods low in the series of the Holothuroids ; nay, in some respects he regards them as having attained to a higher development than all the other Echinoderms, because, among other facts, their bodies are distinctly bi-laterally symmetrical, with the dorsal and ventral surfaces distinct, and often with a cephalic region well marked. Only the ventral ambulacra are subservient to loco- motion ; these latter show a tendency to appear definite both as to place and number. The dorsal appendages are so modified as to perform functions different from the ventral ones. The report gives full details of all the new species. Coelenterata. Nematophores of the Hydroida.{—C. de Mereschkowsky has investigated the structure of the nematophores with regard to the * Reports on the Scientific Results of the Voyage of H.M.S. ‘Challenger’ during the years 1873-6, vol. iv. (1882) 176 pp. and 46 pls. Cf. Nature, xxvii. (1882) pp. 74-5. + See this Journal, iii. (1880) p. 268. ¢ Bull. Soc, Zool. France, vii. (1882) pp. 280-1. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 71 general view that they consist not of cellular tissue, but of a struc- tureless protoplasmic mass. He finds that these organs not only con- sist of cells, but that an ectoderm and endoderm and even a membrana propria are also present. The endoderm forms a solid axis, which at the base of the organ unites with the endoderm of the stem. The ectoderm, which covers it, is alone the seat of the amceboid move- ments, which take place chiefly at the superior extremity, where the endodermic axis is wanting. The cause of the movements is explained by the structure of the ectoderm. Its cells are immersed in a con- tractile protoplasmic mass, to whose contractility the movements are due. Though these organs have no cavity they may be considered as degenerated polyps: (1) because their tissues are the same; (2) because each has a calyx; and (3) because the polyps can in certain circumstances transform themselves into a nematophore. The author’s observations were made on one species of Plumularia, two of Antennularia, and two of Aglaophenia. In the case of one of the latter he found that the tissues constantly contained parasitic alge ; the endoderm “yellow cells,” and the ectoderm a green alga belonging to the Phycochromacez. Green-cells of Hydra.*—In a contribution to the interesting ques- tion of symbiosis, O. Hamann points out that while Brandt believes that chlorophyll in animals is always associated with the presence of algae, Geddes finds that supposed chlorophyll-containing animals may have (1) no chlorophyll, but green pigments—e. g. Bonellia; (2) forms with intrinsic chlorophyll—e. g. Convoluta, Hydra, Spongilla ; and (3) “those vegetating by proxy” in which alge live. The ques- tion that has to be answered is—How do the green-bodies enter the egg of Hydra, which for a certain time is free from them, and which itself arises from the ectoderm, in which green-cells are never found ? The author put some Hydre into a test-tube, and filled a quarter with water ; when the animals were fully extended he added two drops of 1 per cent. solution of acetic acid; to this drops of 5 per cent. solu- tion of chromic acid were added, until the water had a distinct yellow colour.» The test-tube was then filled up with 70 per cent. alcohol ; the solution drawn off, and alcohol gradually added until it was finally absolute. The animals were coloured by borax-carmine, then brought for a few minutes into absolute alcohol, cleared up with chloroform, and imbedded in paraffin. In sections the protoplasm of the cells is found to have a rosy colour, while the green-cells retain their original tint. If we direct our attention to the ovary, we see that, so soon as it begins to be formed, there commences an increase of the green-bodies at the corresponding point in the endoderm; and this is evident even to the naked eye, and from the exterior by the darker coloration of the animal at this point. At the time when, to use the words of Kleinenberg, the ovum has the form of a “butterfly with outspread wings,” the green-cells are to be observed in it ; they wander into the egg, from the endoderm, at the breaking-down of the supporting * Zeitschr. f. Wiss. Zool., xxxvii. (1882) pp. 457-64 (1 pl.). 72 SUMMARY OF CURRENT RESEARCHES RELATING TO lamella ; the migration continues, and their number increases. The migration would seem to be passive, and dependent on the stream of nutrition which enters from the endoderm. Cultivation-experiments led to the conclusion that we have to do here, as also in Spongilla and Paramecium, with the lowest unicellular alge, which multiply by tetrad-formation; starch-granules as well as chlorophyll (and a nucleus) may be made out in their interior. Basing himself on these observations, the author feels justified in expressing a belief that whenever chlorophyll is found in the animal kingdom we have to - do with green algx, which live in the animals. Prof. E. Ray Lankester * lodges a protest against the reception of Mr. Hamann’s conclusions as reasonable, and repeats the views he has previously expressed ¢ that there is no more and no less evidence for considering the green corpuscles of Hydra viridis as parasitic alge than there is for taking a similar view with regard to the green corpuscles in the leaf of an ordinary green plant. Development of the Ovum of Podocoryne carnea.{—In this species, A. de Varenne has already shown that the ova do not originate in the interior of the Medusa, but in an endodermic cell of the coenosare of the hydra-polyp itself. This cell differentiates and then passes into a diverticulum, which, developing, becomes a Medusa. This Medusa detaches itself from the polyp, and swims free, carrying the ova, which occupy the walls of the manubrium and there arrive at maturity. He now describes the development of these ova, few obser- vations only having hitherto been made on the species with free Medusz, and as the result concludes that, in Hydroida which have a free Medusa, the ovum presents the same development as in the species which have sporosacs that remain always attached to the colony. ‘Challenger’ Deep-Sea Meduse.§—The deep-sea Medusee, which are described by Prof. E. Haeckel, form one of the smallest and least important groups of the rich and remarkable deep-sea fauna discovered during the voyage of the ‘Challenger. The number of species described does not exceed eighteen, of which half are Craspedote and half Acraspedz. They were briefly diagnosed in the ‘System der Medusen’ in 1879, || but they are here described at great length and with a most splendid series of illustrations. The descriptive portion of the memoir is prefaced by a very elaborate sketch of the com- parative morphology of the Medusx, which is illustrated by many woodcuts, It would seem by no means certain that all the eighteen species are constant inhabitants of the deep sea. The method of capture by the tow-net, by which such delicate and fragile organisms are brought * Nature, xxvii. (1882) pp. 87-8. + Quart. Journ. Micr. Sci, xxii. (1882) pp. 229-54. + Comptes Rendus, xciv. (1882) pp. 892-4. § Reports on the Scientific Results of the Voyage of H.MLS. ‘ Challenger’ during the years 1873-6, vol. iv. (1882) ev and 154 pp., 32 pls. and 15 figs. Cf. Nature, xxvii. (1882) p. 74. || See this Journal, iii. (1880) p. 272. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 73 from great depths, is still imperfect, and it seems probable that the greater number brought up apparently from the greater depths really swim in shallow water, and are only taken in during the “ hauling-in” of the net. But Prof. Haeckel considers that those Medusze which have either adapted themselves by special modification of organization to a deep-sea habit of life, or which give evidence by their primitive structure of a remote phylogenetic origin, may with great probability be regarded as permanent and characteristic inhabitants of the depths of the sea; and as such he regards fourteen out of the eighteen described. With regard to the illustrations, the author states :—‘“It is of course impossible, from the imperfect state of preservation of the spirit specimens, to expect that they should be absolutely true to nature. I rather considered it my duty here, as in those figures in my ‘System der Medusen,’ which were drawn from spirit specimens, to take advantage of my knowledge of the forms of the living Medusze to reconstruct the most probable approximate image of the living forms.” ‘Challenger’ Corals.*—Mr. H. N. Moseley describes the Hydroid, Aleyonarian, and Madreporian Corals obtained by the ‘Challenger. The chief results embodied in the first and second parts have already been published in the author’s communications on the Hydrocoralline and Helioporide, though they have been recast, and contain both additions and alterations; but the third part comes as a fresh work, the preliminary catalogue of the deep-sea Madrepores having been necessarily very imperfect. We have now extended de- scriptions and figures of the entire series of species dredged during the voyage with thirty-three species described for the first time. These deep-sea Madrepores would appear to be very widely dis- tributed, some, as for example Bathyactis symmetrica, having a world- wide range. At present the only genera which seem restricted in range are Stephanophyltia and Stephanotrochus, which have as yet only been obtained from the seas of the Malay Archipelago, and in com- paratively shallow water, and the genus Leptopenus, which has been dredged throughout all the great oceans, but only south of the equator. The wide range of species in depth has now become a well-known fact, though none the less interesting for that, the world-distributed species above-mentioned ranging in depth from 70 to 2900 fathoms. The occurrence of the genera as fossils in Secondary and Tertiary deposits is also not without interest; but the deep-sea forms are not to be regarded as of greater geological antiquity than those found in shallow water. Morphology of the Coral-Skeleton.j—G. v. Koch, after a brief review of the opinions of previous writers, reminds us that the separate polyp is always a more or less cylindrical tube, with a mouth at one end; thence an internal tube passes into the cavity. Around the * Reports on the Scientific Results of the Voyage of H.M.S. ‘ Challenger’ during the years 1873-6, vol. ii. (1881) 248 pp. and 32 pls. Cf. Nature, xxvii. (1882) pp. 73-4. + Biol. Centralbl., ii. (1882) pp. 583-93. 74 SUMMARY OF CURRENT RESEARCHES RELATING TO mouth are the tentacles. The body-wall consists of ectoderm, meso- derm, and endoderm. The first and last are composed of epithelial cells, not separated by any intermediate substance. The mesoderm, on the contrary, always consists of a continuous plate of hyaline sub- stance, in which cells and groups of cells are very irregularly deposited. From it there proceed to the digestive tube a number of radially arranged, lamelliform processes, which are invested on either side by endoderm, and with a varying amount of muscular fibres. The number of these partitions is often constant for a whole group of corals. The skeleton, under which term all the hard parts may be included, consists either of numerous small particles, separated by soft substances, or of larger, connected pieces, which may belong to a single animal, or to a whole colony. The relative proportion of organic to inorganic substances varies greatly, and we have all stages between skeletons in which there is but a minimum of inorganie sub- stances (horny skeletons), and those in which the inorganic materials are superabundant (calcareous skeletons). The simplest forms of the latter are the isolated and often microscopic spicules, which are found in most Alcyonaria and in Polythoa. They are always found in the mesoderm, rarely project into the ectoderm, and never into the endo- derm. Occasionally simple, they are often very complicated in struc- ’ ture. Microscopic examination, after decalcification, shows that they are formed of concentric layers of more or less horny intermediate substance, and of calcareous crystals; the layers of the former are very thin, and can only be found in their natural positions with the greatest eare. In Gorgonia or Clavularia (the only two forms which have as yet been examined with regard to this point), it has been found that the spicules always arise in cells, which are always primitively ecto- dermal, and afterwards pass more or less deeply into the mesoderm. The spicules are at first smooth, often triangular, needles, which are at first perhaps hollow, and only take on their definite form by the gradual deposition of new layers. The nucleus of the mother-cell is long persistent, but the protoplasm becomes a very thin layer. The larger calcareous masses, which are found in the axes of the colonies of such forms as Corallium or Melithea, arise from separate spicules, which become connected together by the deposition of fresh calcareous substance; and that, without the spicules themselves becoming altered in character, With this may be associated the arrangements seen in Tubipora, where the separate spicules may be seen gradually passing into a connected lamella. We come next to the Madreporaria, and here, if we take a separate polyp, we may distinguish a sclerobase from the septa, which are con- nected with it, and may be regarded as direct continuations of it ; thirdly, there is a theca, which holds the same relation to the sclerobase and the body-wall, as do the septa, with the peripheral ends of which last it is fused; lastly, there is the exotheca, which is very frequently wanting, and which is nothing more than a continua- tion of the sclerobase. This skeleton consists of crystalline spheroids, which are either directly connected with one another by means of their ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 75 peripheral ends, or by small isolated crystals. According as the skeletal pieces are formed by solid masses, or by numerous lamellz, with intermediate spaces, we have the Madreporaria aporosa, or porifera. The development of the skeleton has only been worked out in Astroides calycularis, and there the ectoderm of the pedal disk gives rise to a thin calcareous plate—the sclerobase of the future polypary. The crystalline corpuscles, which make it up, appear to be secreted by the ectodermal cells, and they soon fuse with one another and take on a polyhedral form. The porcellanous membranes, which are found in such forms as Calliactis, probably belong to the skeletal series, and may be regarded as the analogue of the first rudiment of the skeleton. The horny skeletons are either connected secretions of an epithelium, or invest- ments, varying in thickness, of the calcareous corpuscles. The former, when simplest, are thin lamelle which present a striated structure, and are developed from the ectoderm of the foot-disk (some Actinie). In the Cornularide they are better developed, and form a more or less firm test, into which the whole polyp can be retracted. They are made up of thin lamelle, which are not separated by any interspaces, and are only with difficulty separated from one another. In the Antipathide and Gorgonide—e. g. Gerardia—the ectoderm secretes a horny lamella, which differs a good deal in the different families and genera, as to the extent to which inorganic substances enter into its composition. The study of Gorgonia shows that the simple polyps first secrete at their distal end a thin horny lamella. The growth of the axial skeleton is pari passu with the formation of polyps, till at last we have a colony of a number of separate animals, which appear to invest the axial skeleton, although this last is a product of the primitive ectoderm. The axis of the Pennatulide presents a consider- able resemblance to that of the Gorgonide, and in them, too, there is an axial epithelium. The horny sheaths of the spicules must be regarded as products of the cells, and not as hardenings of the intermediate substance ; this is demonstrated by their relations, both in early and late life, to the protoplasm of the cells. These sheaths often secondarily fuse with one another and then form pretty strong skeletal parts, as in the axes of Sclerogorgia, &c. Protozoa. Suctociliata, a New Group of Infusoria, intermediate between the Ciliata and the Acinetina.*—Well-marked characters separate the ciliated Infusoria from the Acinetina; and up to recently no intermediate form has been indicated as forming the passage between the two groups. In the Bay of Naples, however, Dr. C. de Meresch- kowsky met with an intermediate form, presenting at the same time the cilia of the ciliated Infusoria and the suckers of the Acinetina. At first glance it might be taken for a Halterine, to which it presents some resemblances. In size it does not exceed a small Halteria ; its body, which is rounded and somewhat pyriform, ter- * Comptes Rendus, xev. (1882) pp. 1232-5. 76 SUMMARY OF CURRENT RESEARCHES RELATING TO minates anteriorly in a slightly developed conical neck, at the ex- tremity of which there is an aperture. The body is clothed with a thick cuticular membrane, and this presents spirally arranged longitudinal folds. The neck, covered with a thin cuticle, is alone contractile ; at the will of the animal it can invaginate itself in the interior. At the base of the neck there is a collar of long cilia, by means of which the animal can execute two kinds of movements; one slow, as if the animal were creeping over various objects; the others are sudden rapid leaps. The cilia are about as long as the body, stout, rigid, and arranged in three circles placed one above the other ; each circle contains seven or eight cilia, so that the entire collar consists of from twenty-one to twenty-four. A nucleus and a contractile vacuole are present. The most interesting point in the organization of this animal is the constant presence of four suckers, arranged symmetrically upon the margin of the orifice of the neck. They are very short, not so long as the neck; and in structure are the same as the suckers of the Acinetina. When the neck becomes invaginated, the suckers are like- wise carried into the interior, and cannot then be observed. It is this position that the animal usually presents, and it is then easily mis- taken for a ciliated Infusorian. Sometimes the animal fixes itself, by means of its suckers, to various objects ; or it may creep slowly by the aid of its cilia, with the mouth open and the suckers directed forward. This Infusorian was first found by Cohn, who gave a very super- ficial description of it under the name of Acarella siro. The essential character of the presence of the four suckers, as well as several other characters, escaped him; and this led him to place it among the Ciliata. As, however, by some of its characters it is a ciliated Infu- sorian, and by others an Acinetine, it is necessary to form for it, at least, a distinct family, which the author proposes to name Suctociliata. This family may be arbitrarily arranged in either of the orders as an intermediate form ; or, if it be preferred, as a new order Suctociliata. It remains to be learned whether the Suctociliata are not ancient rimitive forms which may have given origin, on the one hand, to the Ciliata, by the disappearance of the suckers, and, on the other, to the Acinetina, by the suppression of the vibratile cilia ; or should we not rather regard Acarella siro as a Ciliate which has acquired suckers without having any genealogical relations with the Acinetina? or, lastly, as an Acinetine which may have retained its embryonic cilia until its adult age? We cannot choose any one of these three suppositions as being the most probable, all three of them having considerations in their favour. The developmental history of the Infusorian, which is very difficult to study on account of its rapid movements, can alone decide the matter with certainty. The last of the suppositions, however, seems the least probable. M. E. Maupas adversely criticizes* Mereschkowsky’s views, pointing out that Stein’s Actinobolus varians is a better intermediate form, and that the author is im error in saying that the Acinetide have vibratile cilia only in their embryonic state, as some Podophrye * Comptes Rendus, xcy. (1882) pp. 1381-4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 17 and all the Spherophrye are able to resume their cilia and become free. The form described is moreover very common, and has been previously published by Claparéde. and Lachmann, Fresenius, and Quennersted, as well as by Cohn. He also considers that the assimi- lation of the “suckers” to those of the Acinetide is a purely gratuitous assumption not resting on any positive observation, the so-called suckers never having been observed to act as such but solely as fixing organs. Further the vibratile appendages of the Acinetide are always simple vibratile cilia, whilst in Acarella they are compound or true cirri, and represent therefore the higher state of development. M. Maupas adheres to his view * that the ancestral affinities of the Acinetidz are with the Heliozoa rather than with the Ciliata. Dr. Mereschkowsky replies} to this criticism, maintaining the correctness of his original paper on all points. New Infusorian belonging to the Genus Pyxicola.[—Professor J. Leidy describes an infusorian, a species of Pyxicola, which ap- peared to be different from those previously described. It is of fre- quent occurrence, attached to the tubes of Plumatella, Urnatella, and Cordylophora, on stones. In shape it resembles Pya«icola pusilla and P. affinis, fresh-water forms of England, but is annulate as in P. socialis, a salt-water form. It presents the following characters :— Pysxicola annulata. Lorica urceolate, slightly curved, inflated towards the middle, tapering below, cylindrical and feebly contracted at the neck, and with the aperture oblique and circular, variably annu- late, mostly at the neck, often at the middle; colour chestnut-brown, but colourless when young ; pedicle short, always colourless. The eon- tained animalcule is of the usual shape, with an attached operculum, which is of the same colour as the lorica, and is protruded beyond this when the animal is fully extended. - Length of lorica, 0°52 to 0°792mm.; breadth, 0:02 to 0°0264 mm.; length of pedicle, -004 to -008 mm. Systematic Position of Amphidinium.$—R. §. Bergh supple- ments his previous observations on the Cilio-flagellata by a note, in which he places Amphidinium with the Gymnodinide, and not with the Dinophyide, as he originally proposed. Evolution of the Peridinina.||—M. Pouchet brings forward some observations which, he thinks, reveal a new order of phenomena in the genesis of the Peridinians. The different varieties of Ceratium Jurca and C. tripos always occurred, as usual, isolated, of equal size, and with no traces of any genesic operations, until, on October 9th, a single cast of the net furnished no fewer than three forms of Ceratia, namely, C. tripos and its var. megaceros, and C. furca, arranged in ‘chains of two, three, and up to eight individuals joined end to end. The boat was four or five miles off the shore; and the depth was 80-100 metres. These curious chains are probably formed at the bottom. The mode of union of the individuals is as follows :—The * Cf. this Journal, ii. (1882) p. 639. ; + Comptes Rendus, xcvi. (1883) pp. 276-9. t Proc, Acad. Nat. Sci, Philad., 1882, pp. 252-3 (2 figs. of a plate to follow). § Zool. Anzeig., v. (1882) pp. 693-5. || Comptes Rendus, xcv. (1882) pp. 794-6. 78 SUMMARY OF CURRENT RESEARCHES RELATING TO aboral or posterior horn (anterior of Stein) is inserted by a truncated extremity at the left-hand margin of the ventral depression of the succeeding individual, just at the point of termination of the transverse furrow. The individuals in chains were motionless, with neither flagellum nor cilia. This arrangement, and especially the apparent. anterior evolution, would seem to approximate the Ceratina to the Diatoms and Desmids, while other peculiarities appear to indicate a relationship between these creatures and the Noctiluce closer than that accepted by Stein, who places his groups Scytomonadina between the latter and the Peridinina. Some large Ceratia allied to C. divergens, and about 0:160 mm. in length, show remarkable characters. The protoplasm, pro- tected by the carapace, is slightly rose-coloured, with a large spherical nucleus and some drops of oily appearance and of a bright chamois- colour; the creature is asymmetrical, and as if twisted upon its axis ; the extremity (truncated as usual) of the aboral horn appears excavated into a groove; and on the right-hand side of the ventral depression there is a strong projection in the form of a lamp (Claparéde and Lachmann, Stein). All these characters occur in a striking manner in the Noctiluce, especially at the moment of an ascent of these creatures to the surface of the sea :—flagellum (Huxley, Robin, Stein) ; envelope hyaline, resistant, sometimes distinctly reticulated; rosy coloration of the protoplasm, with a nucleus and oily drops of the same dimensions and the same colour ; well-marked asymmetry in the basal piece of the tentacle and lip projecting on the right side (Huxley, Robin). Tie analogy becomes still more manifest if, instead of spherical floating Noctilucee, we take the forms which have already puzzled Busch, and which are not found at the surface, but at the bottom of the vessels in which the products of fishing have been collected. In these the internal framework (formed, not by a style or bacillus, but by two kinds of glumes) produces by its extremities, three processes or horns—two in front, pointed, and more or less recurved, and a third aboral, excavated into a groove. The size of these tricuspid Noctiluce (0°190 mm.) scarcely exceeds that of the large Ceratia from which they seem to have issued, to become subsequently swelled up by accumulation of water in lacune originally independent of their protoplasm. In these Noctiluce there is often a prominent curved projection, which seems to mark the contour of the ciliary circlet. Of the formation of the tentacle the author can say nothing, and he remarks that the suggested relationship is purely hypothetical. New Thuricola.*—Dr. A.C. Stokes describes a new species of Kent’s recently established genus Thuricola (T. innixa) found on the leaflets of Ceratophyllum. The lorica is sessile, transparent, sub-cylindrical, four to five times as long as broad, truncate, and somewhat tapering posteriorly, bearing at some distance from the orifice an internal valve-like appendage as in T. (Vaginicola) valvata, and an opposite, rigidly attached, but flexible, membranous organ projecting arcuately * Amer. Mon. Micr. Journ., iii. (1882) pp. 182-3 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 79 inwards, and acting as a support to the edge of the descending valve, the wall of the lorica being dilated laterally immediately behind this, in optical section bristle-like, valve-rest ; body pedicellate, hyaline, projecting when extended one-third its entire length beyond the orificé of the lorica; pulsating vesicle anterior, contracting once in fifteen seconds. Flagellata.*—J. Kiinstler’s extended article on this subject appears in the first part of the French Zoological Society’s Bulletin. This has only just been distributed to Societies exchanging, although pur- chasers have long been in possession of it. It is much to be wished that some of the foreign Societies could be induced to forward their publications (as the Royal Microscopical Society does) immediately on issue, instead of one, two, or even three years after date, as is now often the case. The present article has already been anticipated, and a brief extract of it appeared in Vol. IT. (1882) p. 62. We may add here that it comprises the following parts :— (1) Introduction and historical view (in which the various systems of classification are discussed). (2 and 3) Descriptive part (which deals with the exterior, flagella, integuments, physiological considera- tions, digestive apparatus, general cavity, vestibulary tube, contractile vesicle, oculiform point, reproductive apparatus, and development). (4) General considerations (cell, and protoplasmic spherule). (5) Sys- tematic considerations. (6) Bibliography. A “further contribution” on the same subject { was abstracted at p. 518 of Vol. II. (1882).+ Prof. O. Biitschli § ridicules the author’s views of the organization of the Flagellata, and his description of the complicated structures which he discovered in them in the way of stomach, intestine, uterus, &c., and in particular depreciates the value of his observations by point- ing out that the new genus Kiinckelia gyrans which he founded, and of which he gives elaborate woodcuts, is, in fact, neither more nor less than a Cercaria ! Microsporidie or Psorospermie of Articulates.||—E. G. Balbiani, as the result of investigations on their mode of reproduction, proposes to designate as “ Microsporidia” or Psorospermiz of the Articulates the “corpuscles” of the silk-worms which he considers to be nothing else than the spores of an organism having affinities with those for which Leuckart proposed the name of Sporozoa, which includes already (1) the Gregarinide, (2) the oviform Psorospermie or Coccidiz, (3) the tubuliform Psorospermiz or Sarcosporidiz, and (4) the Psorospermiz of Fishes or Myxosporidiz. The microsporidia of Attacus Pernyi is formed when young of a * Bull. Soe. Zool. France, vii. (1882) pp. 1-112 (8 pls.). + Ibid., pp. 230-6 (7 figs.). t In his first paper the author throughout calls the species to which his description refers, Cryptomonas ovata Ehrbg., though at the same time he ex- presses his opinion that his species was in reality a new one, Heteromitus olivaceus. Tn the second paper the latter name only is used. § Zool. Anzeig., v. (1882) pp. 679-81. || Comptes Reudus, xcy. (1882) pp. 1168-71. 80 SUMMARY OF CURRENT RESEARCHES RELATING TO small mass of homogeneous plasma, which grows, and clear nuclei appear in the interior, each of which is surrounded by a layer of plasma; these are the young spores. Their substance condenses, they take an oval form, and the nucleus ceases to be visible. The ripe spores are identical in size and appearance with the “ corpuscles” developed in silk-worms attacked with pelvine. They resemble the spores of some Bacilli, B. amylobacter for instance, and their mode of germination is nearly the same, that is, it is effected by the perfora- tion of the spore at one of its extremities and the exit of the interior plasma, but instead of taking the form of a rod, as in the Bacilli, it escapes as a small amceboid mass, which reproduces the vegetative phase of the parasite. Another species of microsporidia was found in an Orthoptera, Platycleis grisea, and like the former, in the epithelial cells of the stomach. Development of Gregarine and Coccidia.*—Gregarines of the genus Stylorhynchus are found by Schneider to produce rosary-spores ; the contents of these spores consist at first of granular protoplasm with large spherical nucleus, but subsequently become converted, in each case, into eight falciform bodies, each with a separate nucleus. If to the mature spores is added, under the Microscope, some fluid from the intestine of a Blaps, they open spontaneously along their convex border, and the sporozoites issue by the movements of their anterior extremity. If observed for some time, they seem to endeavour to penetrate the subjacent surface, which would under normal conditions be an epithelium. Observations of the tissues of the Blaps seem to Schneider to confirm this supposition; for on macerating the intestine, its cells are found each to contain, by the side of its nucleus, a body identical with a Coccidiwm, viz. provided with a nucleus of its own and occurring in all conditions from the earliest stage up to that at which it issues into the alimentary tract by bursting the cell which incloses it. In order to assume the Monocystis-form, it has now to divide into segments. The original nurse-cell persists as a cap on the head of the Stylorhynchus. Coccidia.—Spores of the genus Klossia develope as follows :— Directly after the formation of the cyst, the nucleus consists of a wall, a nuclear liquid, and a freely suspended nucleolus, consisting of an external, dense, and an internal, more fluid, layer; there is no reti- culum. In the following stages the nucleus buds out globules one by one—to the number of 30 in one instance observed—which form a bunch upon it. These bodies probably grow at the expense of the nuclear liquid; the nucleolus diminishes in proportion to their growth: they seem to undergo fission, for some are found constricted across the middle and inflated at their extremities. In the next stage the wall of the nucleus disappears, and the globules are set at liberty among the granular contents of the cyst. The globules reach the periphery, apparently by automatic movements; they subdivide frequently in the cortical zone of the cyst, and during the process * Comptes Rendus, xcvy. (1882) pp. 47-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 81 present the form of long ribbons expanded at the ends and very attenuated in the middle; their division results ultimately in the production of an enormous number of small nuclei, distributed over the external layer of the cyst at close and regular intervals. Soon each of these nuclei recedes from the cyst, causing a projection from its surface and drawing out with it a conical protoplasmic process ; this, inclosing the nucleus, becomes detached from the cyst by constriction of its base, and constitutes a spore. Gregarinide of Annelids.*—Professor J. Leidy describes and figures four new species: Monocystis mitis in Distichopus (remarkable from its frequently containing a variable number of curved elliptical bodies—spores ?), Anoplophrya modesta and A. funiculus in the body- cavity of Enchytreus, and A. melo in that of a species of Lumbricus. Intestinal Parasites of the Oyster.t—In a further communica- tion,t A. Certes describes the methods by which he obtained the con- tents of the stomach of the oyster. A narrow tube is introduced into the mouth of the animal, and the contents drawn out by suction ; in this way the misleading presence of hepatic and generative cells is completely avoided. Although the contents do not redden litmus paper, the calcareous tests of Foraminifera are dissolved in the stomach. The use of dahlia-violet, which colours living specimens and slows their movements, has resulted in the demonstration of the presence of a small oval nucleus. Attention is directed to the use of methyline blue, which the author uses either to colour organisms already killed and fixed by osmic acid, &c., or as a reagent for living protoplasm. In the latter case, a drop of the alcoholic solution is placed on a slip, and allowed almost to evaporate; a drop of the liquid to be examined is then added, and as soon as it begins to be coloured the solution is tipped over, and the presence of crystals thereby avoided. By this means it is not necessary to add distilled water or alcohol, which would immediately kill the organisms. There are some observations on Enchelyodon, but the author is not yet satisfied as to the family to which it belongs; and on Prorocen- trum micans, in which a nucleus has been detected; no observations could be made on its supposed phosphorescence. Perception of Light and Colour by the lowest Organisms. s— The instances in which these faculties are exhibited in the lowest forms, even extending to some true plants, are very numerous, but hitherto have met with little explanation. T. W. Engelmann has now turned his attention to the subject. The facts which he has dis- covered, or with which he is acquainted, appear to him to point to three principal modes by which light is able to affect these organisms, V1Z. :— * Proc. Acad. Nat. Sci. Philad., 1882, pp. 146-8 (4 figs.). + Bull. Soc. Zool. France, vii. (1882) 7 pp. (1 pl.). I See this Journal, ii. (1882) p. 804. § Pfliiger’s Arch. Physiol., xxix. (1882) pp. 387-400. Ser. 2.—Vot. III. G 82 SUMMARY OF CURRENT RESEARCHES RELATING TO 1. Directly, by modification of the interchange of gases, without apparent addition of a sensation. 2. By modification of the sensation of necessity for breathing, owing to modification of the interchange of gases. 3. By setting up a specific process, which probably answers to our sensation of light. Of these, the first may occur either alone or in combination with the second; simultaneous occurrence of the first and third may pos- sibly take place. 1. Navicula is taken as type of the first method, and most mobile Diatomacez and Oscillarinew belong to the same class. Péinnularia was also examined. Movement is here intimately connected with the presence of free oxygen, which, if not present, can be produced by these organisms in the light. It is for this reason that light is able to revive the movements when they have ceased through want of oxygen in the darkness, whereas when sufficient oxygen is present already in the water, the light exercises no distinct influence on the energy of the movements. After movements have ceased owing’to want of light, they may be made to recommence by placing the diatom in the red part of the spectrum. It is found that red between the lines B and C promotes movements the most actively, while ultra-red and ultra-violet are quite ineffective. The relation to the colours of the spectrum, together with the amount of light required (which is con- stant), agree with those indicated by the bacterium test. Taking that of the red between Band C as the maximum, the percentage of energy developed by the other colours is :— Extreme red (a) 22°7 Green (E 3 b) 14:1 Extreme blue (F) : 6:9 Violet (G) .. a 1°2 2. Paramecium bursariaa—When the proportion of oxygen is normal, or somewhat greater than the normal amount, the Infusorian is usually very quiet; if, however, it sinks ever so little below this degree, the animal becomes restless, and makes for places in which there is more oxygen (e. g. edge of cover-glass); in good light, but under otherwise similar conditions, the specimens distribute them- selves equally throughout the drop. Active swimming is the con- sequence of serious diminution of the oxygen ; if strong light is then applied for some minutes, the Paramecium courses rapidly about, and if insufficient supplies of oxygen are added from without, it shows itself very sensitive to alterations in the illumination in the spectrum ; it prefers red of between the lines BandC. The obvious explanation of this and other details is that, in default of oxygen from without, the chlorophyll contained in the mesoplasm acts as it does in plants— viz. excretes oxygen; it exhibits in its action the same dependence on amount and quality of light as do the movements of the animals. The energy of the excretion is as follows for different parts of the spectrum, taking the red between B and C as 100 :— ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 83 In sunlight. In gaslight. Outer red (a) 9°7 bs 24°7 » yellow (D) . 35°2 vs 23°3 » green (H § b) 14°6 Ae 6-2 Pom vlites (Hr es. 25°5 or 5:3 Pe violetc(G). <3. 8:2 a 0:8 High tension of oxygen reacts strongly on the movements, for the animals then tend to swim straight or in wide curves away from the point at which oxygen is present in abundance. Strong illumination applied suddenly at this time causes violent movements, and the Para- mecium often darts into the darkness, exhibiting the phenomenon of photophobia. Thus this animal is very highly sensitive to differences in the tension of oxygen. 3. Huglena viridis is taken as the third type. It appears that in both it, Colacium, Trachelomonas, and some allied forms, the tension of oxygen has little to do with the movements. In darkness and great dearth of oxygen gradual dissolution produces, naturally, an increasingly feeble sensitiveness to light; but even under high tension of oxygen the reaction with light appears to be always less than usual. When the drop of water is partially illuminated the Huglene gradually assemble in the lighted area, and usually remain there; if a shadow is thrown upon the anterior chlorophyll-less portion of the body the animal turns and behaves as if wholly in darkness. This is not due to the eye-spot which is placed here, as the reaction is effected when the darkness first reaches the protoplasm outside it. This sensitive- ness of the anterior end of the body is generally distributed amongst animals, and occurs in Paramecium bursaria, in spite of the greater amount of chlorophyll contained in the posterior part. The differ- ence between Paramecium and EHuglene in relation to light is more distinctly shown by the use of the spectroscope ; whereas the former prefers the slightly refrangible red rays, the latter prefers the blue end of the spectrum, whether gaslight or daylight is employed. The following is a good average sample of the way in which Euglene dis- tribute themselves over the spectrum, and should be compared with the tables given above :— Between A and C 3-4ths D (red to orange) .. 2 individuals. j » ©3-4thsDand D5-6ths EH (orangeto green) 0 - » D 5-6ths E and b 5-6ths F (green) i EG a » ©05-6ths F and F 4-7ths G (green to blue) 100 fr F 4-7ths G and G (blue to indigo) tes poe a 5 G and G 3 H (indigo to violet) .. Sees Fs ‘In the spectrum the individuals swim in all directions, as in com- plete darkness. The sensitiveness to minute differences in the quality of the light is decidedly greater in the red, yellow, and green than in the blue. Engelmann has not as yet succeeded in finding blind or colour-blind Huglene, but individuals from different localities and in different stages of development often show important variations in their sensitiveness to light. qe 2 84 SUMMARY OF CURRENT RESEARCHES RELATING TO BOTANY. A. GENERAL, including Embryology and Histology of the Phanerogamia. Development of the Pollen of Orchidee.*—L. Guignard has investigated the structure and mode of development of the pollen in Orchidew, especially in the Ophrydez and Neottiez. The primordial mother-cells of the pollen are formed from a hypodermal layer, each of whose cells divides into an outer and an inner cell, the latter becoming the pollen mother-cells. They constitute, therefore, at first a simple layer, and are distinguished from the other cells by their denser cell-contents. Hach of these cells further divides in different directions, and developes into one of the “ massule,” the peripheral cell-walls of which are much thicker than the inner walls. The outer hypodermal layer also undergoes numerous divisions, dividing into an inner layer, the “tapete,” and an outer layer the walls of which are strongly thickened, but do not, as in most other plants, become fibrous. The further development of the mother-cells of the pollen more closely resembles in some respects that of dicotyledons than of other monocotyledons. The cells do not divide completely, but only their nuclei, not even a cell-plate being formed. The two nuclei again divide into four, which are arranged either in one plane or in a tetrahedron. The true membrane of the pollen-grains is formed nearly simultaneous, on the side towards the mother-cell-wall, and in the equatorial plane of the nuclear spindle. It often has a granular extine composed of two layers, the outer one of which, however, occurs only at the periphery of the tetrahedron. During its formation the mother-cell-wall becomes absorbed. The author confirms Strasburger’s and Elfving’s account of the part played by the two nuclei in the act of impregnation. The process can be very well followed out with the assistance of colouring reagents, either in the process of fertilization itself, or by making the pollen- grains germinate in a 2 per cent. solution of sugar. The tetrahedra of Neottia ovata and nidus-avis are specially favourable for observa- tion. Colouring with hematoxylin immediately after the pollen- tube has burst through the extine shows the larger nucleus occupying the swollen extremity; at some distance is the elongated granular vegetative nucleus. At the moment of impregnation this latter has almost entirely disappeared, while the larger nucleus becomes resolved into an amorphous substance which is still coloured by hematoxylin, and passes through the thin wall at the extremity of the pollen-tube. Under artificial conditions the extremity of the tube may often be seen to be perforated. The protoplasm of the pollen-grain has in the meantime entered the tube along with the nuclei, and becomes aggre- gated into balls. Formation of the Pollen-grains in Gymnosperms.t—L. Juranyi has investigated the details of the mode of formation of the pollen in * Ann. Sci. Nat. (Bot.), xiv. (1882) pp. 26-45 (1 pl.), + Bot. Ztg., xl. (1882) pp, 814-8, 835-44. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 85 Ceratozamia longifolia and Zamia furfuracea among Cycadee, and in Pinus Laricio, sylvestris, Pumilio, and Strobus, and Abies excelsa among Conifere. The pollen-grains of Cycadez divide either successively or simultaneously ; both modes may occur in mother-cells from the same anther. In the case of successive division, after the new nuclei have been formed with their uniting-threads, and the cell-plate has already become visible in these latter, corresponding to the plane of division, the cellulose-ring makes its appearance as an externally projecting cushion on the mother-cell. The starch-grains are grouped round the new nuclei, especially on the side nearest the cell-plate. The cellulose-ring projects at a later period into the cell, and meets the cell-plate formed by thickening of the cell-wall. This ring had been previously described by Juranyi and others as the young division-wall. The stretched uniting-threads are by it constricted ; and it is possible that the cell-plate takes part in the formation of this ring. When it has attained a certain width, the new division is suddenly formed at once from the cell-plate, and the division is complete. The same process is then repeated in the daughter-cells, except that the cellulose-ring does not attain so great a breadth and thickness. In opposition to Treub, the author states that the division- wall of the daughter-cells is formed entirely from the cell-plate. In the simultaneous mode of division the process is the same up to the formation of the first cell-plate. The cellulose-ring is usually smaller than in the first case ; when it has attained its full width, the cell-plate is absorbed. The uwniting-threads become afterwards invisible, from the starch-grains becoming forced towards the first division-plane, so that the space between the two nuclear spindles is filled with them. They begin to disappear as soon as the halves of the nuclear plate reach the pole of the nuclear spindle, a few only remaining visible near the nuclei, the whole cell-cavity being occupied by uniting-threads. The cell-plates are now formed, partly between the nuclei, partly in the position of the first plate which has disappeared, and the division is completed by the appearance of a thin septum. After the thickening of the cell-walls, especially the septa, the tetrads remain in this condition for a considerable time. The form of the pollen-grains and the mode of formation of their membrane agree with those of some angiosperms (e. g. Allium odorum, senescens, and nutans, and Tradescantia pilosa, &c.), and the author’s observations agree in essential points with those of Treub. The inner layer of the wall of the mother-cell is always coloured by methyl- green. In Ceratozamia longifolia the mother-cells have not the capacity of swelling so strongly as in Zamia, and their membranes consist of only two layers; the inner one only, which becomes the wall of the pollen-cell, is coloured by methyl-green. After this layer has become detached from the outer layer of the cell-wall, an opening appears in the latter, through which the young pollen-grains escape. The membrane of the pollen-cell is therefore, as in other plants, the innermost layer of the wall of the mother-cell. The process is the same in Conifers, except that the projections 86 SUMMARY OF CURRENT RESEARCHES RELATING TO of cellulose are not nearly so strongly developed. The pollen-grains are unicellular till shortly before pollination. As this time approaches the starch-grains disappear. The single small cell which occurs in Taxus is then formed by division, constituting the unicellular pro- thallium. When the prothallium is multicellular its cells are produced by successive divisions of the large cell behind those previously in existence ; but this process is more readily seen in the Cycadezx than in the Coniferee. The author traces a close analogy between the formation of the prothallium of Gymnosperms and that of the male prothallium of Vascular Cryptogams, especially of Isoétes. The pigments used by the author are methyl-green, anilin-red, eosin, alum-carmine, and picric acid. Conduction of Pollen-tubes.*—Holzner ascribes to the outer integument of the ovule in Hordeum and Bromus an important function in assisting the pollen-tubes to reach the embryo-sac. The cells of this integument are of the same nature and have the same contents as those of the conducting tissue of the style, with which they are in direct connection. Female Flowers of Coniferee.t—Professor Hichler’s paper on this subject has induced L. Celakovsky to reinvestigate it. After reviewing the different theories and explanations enunciated since Robert Brown’s time, he dwells emphatically on the great importance of the study of the anamorphoses (as he calls those monstrosities which are the result of retrograde metamorphosis, in contradistinction to mere pathological changes) and of the teaching they convey. He comes to the conclusion that these are a much safer guide than the microscopic study of the genesis of the organs, which has often misled those who too implicitly relied on its teachings. Investigating the anamorphoses of the Norway spruce, he finds the two lateral carpellary leaves distinctly indicated, and more or less separated and developed. In a more mature state an anterior and then a posterior bract make their appearance; these, Professor Hichler had taken for a third and fourth lobe of his ligula (normally the posterior bract is the third and the anterior the fourth in order). Celakovsky comes to the conclusion that, at least in Abietinez, Hichler’s theory (that the carpellary scale is a mere emergence or ligule of the bract) is quite wrong, and that Mohl’s view of 1871 that the carpellary scale of these plants consists of the two connate lowest leaves of an axillary, other- wise undeveloped, bud connate at their upper edge and producing the ovules on their back, is amply vindicated by all known morphological facts, and is antagonistic to none of them. He further concedes that the same explanation may possibly be the true one for all conifers, and that all morphologists who have treated this question thus far, have, whatever their views, assumed a conformity in this respect in all the tribes of conifers, and a complete homology of their female organs. But he thinks that this is not * SB. Versammlung deutscher Naturforscher u. Aerzte in Eisenach, Sept. 19, 1882. See Bot. Centralbl., xii. (1882) p. 107. + Abh. K, Bohm. Ges, Wiss., xi. See Bot. Ztg., xl. (1882) p. 870. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 87 necessarily so, and that Sachs’ and Hichler’s emergence or ligular theory may be true as to Araucariex, and that thus the cone of these plants is really and truly a single flower. In regard to Taxodinex and Cupressinez he is convinced that an inner fruit-scale really exists, completely adnate to the bract and soon outgrowing it, but he does not venture to pronounce on its nature, because he thus far has no ocular demonstration of it through any anamorphoses. Celakovsky concludes that the arillus of Taxacez corresponds to the ligula of Araucaries. He speaks of the terminal position of the ovule in this tribe as of very little morphological importance, the ovule being really lateral but pushed to the top of an axis. O. Heer, the celebrated phyto-palzontologist, has shown that geologically Abietinese and Taxodinex are the oldest conifers now known, appearing in the Carboniferous period, while Araucaries come up much later, in the Triassic and Jurassic formations. But the relative geological age of the different tribes of plants is of much less importance for the appreciation of their degree of develop- ment and their position in the system, than some suppose. Thus the Cycadeze, the Phanerogams most closely allied to Vascular Cryptogams, are, as Heer states, very uncertain in the Carboniferous, and make their decided appearance first in the Permian rocks, there- fore much later than the more highly developed conifers. To these arguments A. W. Hichler replies,* supporting his previous conclusions by considerations founded by the position of the bracts in the female flowers, and the arrangement and structure of the scales in the mature cones. Flower adapted for Fertilization by Snails. — F. Ludwig describes the structure of the flower of Philodendron bipinnatifidum (Aroidez), which is malacophilous, i.e. incapable of self-fertilization, and fertilized only by the agency of snails, which, entering the spathe and creeping over the flowers, carry the pollen from the male to the female flowers. They appear to be attracted by an intense nutmeg- like odour, which suddenly pervades the inflorescence at the time of maturity of the stigmas, accompanied by a copious exhalation of carbonic acid. Insects and the Cross-fertilization of Flowers. + — H. Heckel adheres to his view that insects are not the cause of the luxuriance of the Alpine Flora, and considers that the observations of C. Musset,§ on the simultaneous existence of insects and flowers at great heights prove that there are insects there and nothing more. M. Heckel maintains that the true cause is to be found in the greater intensity of solar radiation at these altitudes than in the plain. Development of the Wing of the Seed of Rhinanthus.|| The descriptions by different botanists of the seed of Rhinanthus hirsutus * SB. Ges. Naturf. Freunde Berlin, 1882, pp. 77-92. + Kosmos, vi. (1882) p. 347. { Comptes Rendus, xev. (1882) p. 1179. § Cf. this Journal, ii. (1882) p. 653. || Bot. Centralbl., xi. (1882) pp. 362-7. 88 SUMMARY OF CURRENT RESEARCHES RELATING TO All. differ in the presence or absence of a wing. O. Bachmann finds, from the examination of a large number of specimens, a wing almost invariably present, though varying greatly in size; occasionally it is altogether wanting. In an early stage it is always present, its partial or entire disappearance being due to the rapid growth of the endo- sperm. A minute description is given of the mode of development of the wing. Nature of the Growing Point.*—J. Sachs discusses the consti- tution of the growing point in rudimentary in contrast to that in older tissues. Formative substances, such as albuminoids, oils, and carbo- hydrates, are not peculiar to them, but are present in the cellular tissues generally. The growing point, on the other hand, is charac- terized by the storing up of nuclein, and by the large size of the cell- nucleus in contrast to that in mature parenchymatous cells. It is in the tissue of the embryo that the large quantity of nuclein is especially observable; and this substance appears to have a special function in connection with the act of impregnation. The powerful action attributed to substances occurring in such small quantities is analogous to the action of ferments. If nuclein does play the part ascribed to it, it is probable that there are different kinds—one efficient in the formation of the growing points of roots, another in that of branches, and so forth. Apical Growth in Gymnosperms.t—H. Dingler disputes the accuracy of the statement usually made that there is a universal dis- tinction between the structure of the growing point in cryptogams and in phanerogams, in the presence of a single apical cell in the former and not in the latter. In order to elucidate the question, he has made a series of observations on the growing point of the stem of gymnosperms. The tissue was made transparent by maceration in water or treatment with potash. A seedling of a species of Ceratozamia showed an evident apical cell of considerable size, in which three segments were observed ; the first was undivided, the second divided into three, the third into several cells. In a seedling of Picea excelsa an apical cell could also be detected, but not in older plants. In Pinus inops a tetrahedral apical cell was also made out with less certainty, but not in Abies balsamea or Pinus sylvestris or Laricio, With young seedlings of Cupressus pyramidalis, growth by a single tetrahedral cell was deter- mined with certainty, but not with Juniperus communis. In the leaf- buds of Ephedra monostachya no apical cell could be detected, except in a single instance. Cell-Nucleus.}—E. Zacharias gives a very useful and complete summary of the results of the investigations of various workers as to the formation, structure, and function of the cell-nucleus in both * Arb. Bot. Inst. Wiirzburg, ii. (1882). See Bot. Centralbl., xii. (1882) p. 119. d + Dingler, H., Ueber d. Scheitel wachsthum des Gymnosperm-Stammes, 85 pp. (3 pls.). Miinchen, 1882. See Bot. Centralbl., xii. (1882) p, 154. ¢ Bot. Ztg., xl. (1882) pp. 611-6, 627-49, 651-63. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 89 animal and vegetable cells. His own observations lead him to the conclusion that the different elements of the active nucleus are deve- loped out of distinct portions of the nucleus when in a state of rest. Structure and Formation of the Cell-Nucleus.*—The result of a series of observations on this subject by L. Juranyi has led him to very much the same conclusions as those of Flemming f and the later ones of Strasburger. ‘The nucleus is composed of threads and a nucleolus. The former consists of two substances, a fundamental substance (matrix) which is not coloured, and corpuscles imbedded in it which take pigment. These increase and multiply, and finally coalesce; the threads then take the pigment along their whole length, and the nucleolus disappears. In the Cycadez the nucleoli are very large, and consist of a central strongly refringent corpuscle and a thick less refringent envelope, the latter being much less strongly developed in other plants. After the disappearance of the nucleolus the thread becomes gradually thicker, but one or sometimes two strongly refringent particles can be seen on the surface of the nucleus, resembling the nucleoli, but not receptive to pigment. After the threads have become much thicker and shorter they break up, the fragments either becoming applied to the wall, or touching it with one end, the rest dipping into the nuclear fluid. The protoplasm now takes the place of the nuclear fluid, and forces the fragments of the threads towards the plane of division, thus forming the nuclear plate, and the nucleus therefore consists originally of two halves. The fragments mostly take the form of a C or a U, their convex side facing the division-plane. The nuclear spindle now makes its appearance, its fibres being no doubt formed from the cell-protoplasm, as can clearly be made out in the Cycadezw. The elements of the nuclear plate are always fragments of filaments, but the structure of the plate may vary according as its elements remain distinct, approach one another, or coalesce in consequence of the action of reagents. Re- agents affect the form of the fragments so much that the plates of sister-cells may be composed of elements of quite different form, and even the elements of the same plate may differ from one another in this respect. The two halves of the nuclear plate, now fully developed, move to the pole of the nuclear spindle, the fibres of the spindle remaining behind and constituting from this time the uniting-threads. During this movement the fragments of the threads take up such a position that their concave surface faces the division-plane. After the elements of the plate have reached the pole of the spindle, they appear scarcely to move away from the uniting-threads. While this is going on, granular protoplasm is formed round them, which incloses both the fragments of the threads and a portion of the fluid between the uniting-threads and the elements of the plate, and thus is produced the vacuole in which the elements of the new nucleus lie free. The * Ungar. Acad. Wiss. Buda-Pest, Oct. 16, 1882. See Bot. Centralbl., xii. (1882) p. 215. + See this Journal, i. (1881) p. 11. 90 SUMMARY OF CURRENT RESEARCHES: RELATING TO elements which were derived from the plate arrange themselves into a thread, which elongates and has a serpentine form. When the daughter-nucleus divides, these processes are repeated, but the elements of the plate of the daughter-nucleus often differ in form from those of the parent-nucleus. When cell-division follows division of the nucleus, this takes place precisely in the way described by Strasburger. Superficial Growth of the Cell-wall.*—F. Schmitz adduces further evidence in support of his previously published view f that the increase not only in thickness, but also in superficies of the cell- wall, is due not to intussusception, but to apposition. The arguments are drawn chiefly from the structure of the cell-wall in Zygnema, Spirogyra, Ulothrix, and other filamentous alge, in which the outer surface of the cell-wall exhibits very fine markings or even puncta- tions due to very minute pores. If the cell-wall was constantly being stretched by intussusception, this marking would continually increase in scale, which, however, is not the case. On the contrary, the rupture of the outermost passively stretched layer is a very common pheno- menon with alge and other plants, a fact which is in complete accordance with the theory of apposition, while it is difficult to explain on that of intussusception. Mechanism of the Structure of the Cell-wall.t—F. v. Hohnel has carefully examined the behaviour, under various conditions, of the cell-walls of bast-fibres and other elements in the structure of vegetable tissues. From the facts observed, he draws a conclusion adverse to the theory that the cell-wall consists of crystalline micelle. The chief and efficient cause of the optical properties of the cell-wall he considers to be molecular tensions, which, however, occur only between the thinnest layers of the wall. The occurrence of these tensions can, he states, be absolutely proved ; and experiments on fine threads of other substances are sufficient to show that they are competent to produce the phenomena of polarization. The same facts will also account for many peculiarities of the phenomena of swelling which have not hitherto been explained. Function of Lime in Germination.s—Experiments by previous observers on Phaseolus multiflorus had led to the conclusion that lime has no function in connection with the transport of starch in germi- nating seeds; but that it is connected with the transformation of reserve into formative materials, as, for example, of starch into cellulose. A fresh series of experiments by A. von Liebenberg tends to show that plants may be divided into several groups in respect to the presence or absence of lime, and to its function in their germinating seeds, Viz. :— . 1. Lime is absolutely necessary when the reserve-materials are being * SB. Versammlung deutscher Naturf. u. Aerzte in Eisenach, Sept. 19, 1882. See Bot. Ceutralbl., xii. (1882) p, 108. + See this Journal, i. (1881) p. 908. + Bot. Ztg., xl. (1882) pp. 595-606, 616-25. : a Akad. Wiss. Wien, Ixxxiy. (1882) p. 405. See Naturforscher, xv. (1882) p: : ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 91 used up in germination :—Phaseolus multiflorus and vulgaris, Pisum sativum, Ervum lens and ervilia, Medicago sativa, Soja hispisa, Ricinus africanus, Cucurbita Pepo, Cucumis sativus, Brassica oleracea, Cannabis sativa, Helianthus annus, and Zea Mays. 2. The presence of lime is not absolutely necessary :—Brassica napus oleifera, Sinapis alba, Papaver somniferum, Carum Carui. It is very advantageous in Polygonum Fagopyrum and Linum usitatissimum. 3. All nutrient substances are advantageous for the development of seedlings:—Polygonum Fagopyrum, Brassica oleracea and napus oleifera, Sinapis alba, Ricinus africanus, Cucurbita Pepo, Papaver somniferum, Helianthus annuus, Carum Carui, and Zea Mays. 4. Nutrient substances promote the development of seedlings, even when lime is wanting, for a short time :—Polygonum Fagopyrum and Zea Mays. 5. One or two nutrient substances besides lime are required by the germinating seed for the consumption of the reserve-materials :— Medicago sativa. The researches did not positively determine whether lime is necessary for the formation of the skeleton of the cell-wall, or whether its only function is the transformation of starch into cellulose. Structure and Function of Epidermal Tissue.*—M. Westermaier has investigated the structure and function of the epidermal tissue of plants from an anatomico-physiological point of view. Three functions are especially traceable to the peculiarities of the structure of this tissue :—1. The watery contents of the epidermal cells and the thinness of their radial walls point to a function in connection with the interchange of fluid among the cells of the epidermis itself. They constitute, in fact, a system for the storing up of water. 2. The second function relates to the interchange of fluids between the epidermal and the assimilating systems. 3. The epidermal system Serves aS an énvelope or protection for the more delicate tissues beneath. A number of illustrations are given, in which each of these functions of the epidermis is well illustrated. Influence of different conditions on the Epidermis of Leaves. —In confirmation of his previous observations on the influence of abundant nutrition on the formation of stomata and of hairs,t E. Mer finds that the galls produced by insects on vine-leaves possess stomata, even when found on the upper side of the leaves, while, under normal conditions, stomata occur on the under side of the leaf only. The galls on the leaf-stalk of Populus pyramidalis have a thick-walled epidermis with a few stomata, though these are entirely wanting on the thin-walled epidermis of the uninjured part of the leaf-stalk. In Salix, on the other hand, the reverse is the case, stomata being present on the uninjured parts of the leaf, but not on the galls. Insolation has a marked influence on the form of the epidermal cells and on the formation of stomata, increasing the number of the latter, * SB. K. Preuss. Akad. Wiss. Berlin, xxxvii. (1882) pp. $37-48 (1 pl.). + Comptes Rendus, xcv. (1882) p. 395. } See this Journal, ii. (1882) p. 530. 92 SUMMARY OF CURRENT RESEARCHES RELATING TO while in the former the walls become straighter and thicker, the latter being especially the case with the cuticle. The author believes the production of stomata in these cases to be the direct result of the accumulation of nutrient substances. Influence of Light on the Assimilating Tissue of Leaves.*—As a sequel to the investigations of Haberlandt ¢ and others on the struc- ture of the palisade-parenchyma or assimilating tissue of leaves, H. Pick has studied the direct influence exercised on its development by the intensity of the light. In opposition to the statement of Stahl that the palisade-parenchyma is wanting on the upper surface of leaves growing in the shade, the author finds that it is in most cases present (in the case of beech-leaves and Hieracium villosum), but that in proportion to the want of light the length of the cells (in the direction at right angles to the surface) diminishes. In other cases the cells of this layer are round or even elongated in a direction parallel to the surface. Direct influence of sunlight on the development of the palisade-parenchyma was only rarely observed; in one case (Osmunda regalis) different leaves of the same plant, and even different parts of the same leaf, exhibited differences in this respect. The author regards, however, the palisade form of cells as, in most cases, an inherited peculiarity of the mesophyll of the upper side of the leaves exposed to the action of the sun, and very rarely as affected directly by the action of light; the peculiar form of cell is partially developed even in the bud-condition. This conclusion is perfectly in accordance with the fact that the palisade-tissue is present also, though less strongly developed, on the under side of the leaf. The formation of this assimilating tissue is not prevented by a dense covering of hair, the object of which is not so much protection from too intense light as the prevention of too rapid transpiration. In the case of “ compass-plants,” the structure of the leaves of which has recently been described by Stahl, light appears to exercise a direct influence on the form of the assimilating tissue in the nearly erect leaves, the palisade-cells being sometimes formed on one, some- times on the other side, according to the relative intensity of the light. The assimilating organs have the power of always assuming a definite position with respect to the direction of the incident light, either by the heliotropism of the leaf or leaf-stalk, or by the cells themselves placing themselves in a position at right angles to the incident rays, this latter taking place with stalked leaves which are less able to alter their position in relation to light. Development and Structure of Sieve-tubes.$—In pursuance of his previous investigations of this subject,|| E. Russow has now * Bot. Centralbl., xi. (1882) pp. 400-6, 438-46 (1 pl.). + See this Journal, ii. (1882) p. 368. t Ibid., p. 373. § SB. Dorpater Naturf. Gesells., 1882, pp. 257-827. See Bot. Centralbl., xi. (1882) p. 419. || See this Journal, ii. (1882) p. 218, ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 93 examined the structure of the sieve-tubes, and the development of the secondary cortex in dieotyledons and gymnosperms. In Pinus sylvestris the sieve-tubes are nearly square, or longer tangentially, especially in the autumn wood; their walls are thin and stratified, the tangential ones smooth, the radial and terminal pro- vided with sieve-plates. These are divided by irregular ridges into several compartments, each of which is perforated by from three to six pores. A mixture of chloriodide of zinc, iodine, and potassium iodide colours the cell-wall blue, the callus-structure reddish-brown. The contents of the sieve-tubes, while in a functional condition, consist of a parietal layer of protoplasm, mucilage, a watery fluid, and starch-grains. At an early stage they contain several nuclei. Later they lose their contents, and the sieve-tubes are either resorbed, or remain more or less changed. The sieve-tubes of dicotyledons may be divided into two classes : those which have sieve-plates on their more or less oblique terminal walls only, and those which have them also on their lateral walls. Those of monocotyledons agree with those of dicotyledons in essential points; they belong entirely to the second of these classes. ‘hey contain less mucilage, and usually no starch-grains. Those of Pteridophyta bear a close resemblance to those of monocotyledons, especially in the Equisetacee. In both cases they contain small shining spherical bodies which are coloured yellow by iodine. Anatomy of Bark.*—J. Moeller publishes the results of a very large number of observations on the structure of the bark of various trees. As a general result he thus describes the three parts into which bark may be divided :— 1. The outer bark. The formation of cork may take place either immediately beneath the epidermis, or in the epidermis itself, or it is a second or deeper layer of the primary cortex; the inner or outer wall of the cork-cells may be sclerenchymatously thickened; the periderm may be formed at an earlier or a later period; it may be sclerenchymatous or not; the superficial periderm is sometimes permanent. 2. The middle bark. There may or may not be a collenchy- matous hypoderm; the primary bundles may or may not contain bast-fibres and sclerenchymatous cells; crystals, single or in clusters, frequently occur in it, or there may be glands. 3. The inner bark. Bast-fibres and sclerenchymatous cells may both be either present or absent; there may or may not be crystals ; sleve-tubes are a frequent constituent of it. Absorption through the Epidermis of Aerial Organs.t—M. Mer states that in experiments on modes of destruction of the phylloxera, it was noticed that when the woodwork in a vinery was washed with coal-tar oil, the grapes acquired a strong flavour of coal-tar, while the vegetative organs suffered scarcely any injury. It was remarked that while the skin of the grapes remained nearly tasteless, the * Moeller, J., ‘Anatomie der Baumrinden,’ 447 pp. (146 figs.). Berlin, 1882. + Comptes Rendus, xev. (1882) pp. 511-4. 94 SUMMARY OF CURRENT RESEARCHES RELATING TO empyreumatic substances had penetrated into the flesh, and had accumulated chiefly near the centre round the pips, and were found even in the rachis of the bunch. The skin of the grapes was also covered with an external deposit of various hydrocarbons. The con- clusion to be deduced is that gaseous substances are able to penetrate even a thick epidermis, and to be absorbed by the subjacent tissue without previous solution in water. Protein-Crystalloids of the Potato.*—According to H. Karsten the crystalloids of the potato are cells in which other cells, the “nuclear cells,” are inclosed. Their growth is readily followed in boiled potatoes after digesting in slightly acid solutions of alkaline phosphates, from which treatment they in no degree lose their power of development; their cellular nature being very distinctly shown. In many respects they bear a strong resemblance to bacteria. Hypochlorin.j—Experimenting on the hypochlorin-crystals of Pringsheim,t A. Meyer agrees with the conclusion of Frank § that this substance is identical with Hoppe-Seyler’s chlorophyllan. He finds a convenient reagent for its solution to be glacial acetic acid. If leaves of Iris germanica are laid for three days in hydrochloric acid (1 part HCl and 4 parts water) until a few brown crystals appear, and then heated with glacial acetic acid, the green drops which had formed dissolve, and fresh brown crystals appear in addition to the old ones; or they can be obtained at once from the leaves by treatment with the acetic acid. The reaction of these crystals with various reagents is the same as that of those formed by the agency of hydrochloric acid, and is identical with that of chlorophyllan; a solution in castor-oil shows also precisely the same spectrum as that of this substance. Crystals of Chlorophyll.||—J. Borodin describes crystals obtained by the slow maceration of sections of green leaves in alcohol, and then slow drying under a cover-glass, which are not identical with the chlorophyllan of Hoppe-Seyler. They were obtained from a great variety of different plants, but only from about one-fourth of those examined, most constantly from the Pomacee and Amygdalez. They are probably a compound of chlorophyll with some unknown substance. They are much more abundant in leaves of middle age than in either the oldest or youngest. Their colour varies from pale green to nearly black, and their size and shape are very variable ; they have no effect on polarized light. Their properties are constant and uniform; they differ from chlorophyllan in being very stable under the influence of sunlight, as also under that of dilute acids ; they neither dissolve nor swell in hot or cold water, but dissolve * Pharm. Centralh. f. Deutschland, iii. (1882) pp. 185-8. See Bot. Centralbl., xi. (1882) p. 341. + Bot. Ztg., xl. (1882) pp. 530-4. t See this Journal, iii. (1880) pp. 117, 480; i. (1881) p. 479. § Ibid., ii. (1882) p. 528. || SB. Naturf. Ges. St. Petersburg (Bot. Sect.). See Bot. Ztg., xl. (1882) pp. 608, 622. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 95 readily in alcohol, ether, and chloroform; they are quite insoluble in benzin, petroleum-ether, and bisulphide of carbon. Crystalloids of Cupressinex.* — According to J. Dufour the erystalloids in the seeds of Conifer differ in some important respects from those of other plants. In Chamecyparis spheroidea the envelope of the aleurone-grains is at least partially soluble in water. The erystalloids inclosed in them are very small, about 6-12 » long and 5-8 » broad, and belong apparently to the tesseral system. Dilute potash-ley dissolves at first the envelope of the aleurone-grains, the erystalloids being then attacked. They increase in size, but more in one direction than the others, becoming greatly elongated, sometimes to eight or nine times their original length, before they are dissolved, and pointed at the ends. The angle also increases; and the alteration in angle and the stretching usually begin at the two ends, gradually advancing towards the middle; sometimes the stretching begins at one end only, less often inthe middle. As it proceeds transverse fissures often appear, not, however, usually completely dividing them. The inference may be drawn that the crystalloids consist of transverse layers of different capacities for swelling. Treatment with dilute acetic acid frequently causes the crystalloids to split up completely into these transverse layers. The solution of these then begins in the centre of the lamella, and advances gradually to the circumference. The results are also given of experiments on these crystalloids with hydrochloric and sulphuric acid, alcohol, and with polarized light. Non-calcareous Cystoliths.;—H. Molisch finds, in the parenchy- matous cells of Goldfussia isophylla, cystoliths, resembling the ordinary ones in the cortex, but altogether destitute of calcium carbonate. Among the ordinary thin-walled prismatic cells of the pith are poly- hedral or cylindrical sclerenchymatous cells with very thick walls, not unfrequently 1 mm. in length; each of these idioblasts contains a non-caleareous cystolith, occupying either a portion or the whole of the cell-cavity. Sometimes the cystoliths in several adjoining cells unite, and form what appears like a single one of great length per- forating the transverse cell-walls. They differ from all cystoliths - previously described in being usually attached to the cell-walls by several pedicels, which are always short. The non-calcareous cystoliths resemble the normal ones of the. same plant generally in form, except that they are marked externally © by wavy lines instead of ridges. The entire absence of calcium car- bonate is shown by their not effervescing even with concentrated acids, nor forming crystals of calcium sulphate with sulphuric acid. Cal- cination also shows that they are almost entirely destitute of any mineral skeleton. The light red colour produced on addition of phloroglucin and hydrochloric acid, and the deep violet colour by previous treatment with chromic acid on addition of chlor-iodide * Dufour, J., ‘ Etudes d’anatomie et de physiologie végétales’ (1 pl.). Lausanne, 1882. See Bot. Centralbl., xii. (1882) p. 157. + Oesterr. Bot. Zeitschr., xxxii. (1882) pp. 345-7. 96 SUMMARY OF CURRENT RESEARCHES RELATING TO of zinc, indicate that they are composed of slightly lignified cellulose. The non-calcareous cystoliths are found only in the sclerenchy- matous idioblasts of the medullary parenchyma, and are not, like those previously described in Ficus elastica and australis, of a pathological character. They occur also in similar situations in Goldfussia glomerata and Ruellia ochroleuca. Tannin and Aleurone.*—J. Dufour finds that the cells of the embryo of Borrago ave filled with aleurone-grains and drops of oil, and contain also a quantity of tannic acid. The size of the aleurone- grains varies from 1-25 p», the usual size being from 6-13 4. No trace of crystalloids was observed. The alcurone-grains of most Borraginez are insoluble in water, but dissolve at once on addition of potash-ley, with explosive phenomena. In opposition to previous statements, he found tannin present in large quantities, not only in the seeds of Borrago officinalis, but some also in those of the majority of the plants examined ; for example, in all species of Borraginee, and in some Composite and Cinotherex. In the former order Myosotis contained the largest quantity. From Ranunculacee and Solanez it appeared to be entirely absent. The reagent employed in detecting it was usually potassium chromate or ferric chloride, Fe,C],. The greater number of seeds which contained tannin were without endosperm ; it occurred in the embryo itself. In Mirabilis there is an endosperm the cells of which contain nothing but starch, both tannin and aleurone-grains being present in the embryo. The question whether tannin enters into the composition of the aleurone-grains when they are both present in the same cell, the author is unable at present to decide. Phenological Inversions.t—By this term L. Rahn understands the inversion of the ordinary succession of blossoming in flowers, caused by abnormal meteorological conditions. From observations extending over twenty years in the botanic garden at Giessen, he states that the time of the first opening of flowers depends not only on the minimum daily temperature, but also on the amount of precipita- tion of moisture, and lays down the following general rules :—(1) The blossoming of any particular plant depends on a certain sum of tem- perature, which should be reckoned in our latitudes from about the Ist of January; and, secondly, on the height of the mean daily minimum temperature. (2) A minimum above the mean corresponds to an earlier, a minimum below the mean to a later mean blossoming. (3) The influence of the daily minimum is balanced by a high daily sun-maximum, by precipitation of moisture at the time of blossoming, by general moisture, by a striking deficiency in the daily precipitation, by general dryness, and by the action of late frosts. (4) High sun- maxima may altogether counteract the retarding action of a low daily * Dufour, J., ‘Etudes d’anatomie et de physiologie végétales.’ Lausanne, 1882. See Bot. Centralbl., xii. (1882) p. 156. + Ber, Oberhess. Gesellsch. Nat. u. Heilkunde, xxi. (1882) pp, 113-44 (1 pl.). See Naturforscher, xy. (1882) p. 401. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 97 minimum. (5) Precipitations which take place with a high minimum always delay the first blossoming. (6) Precipitations with a low minimum always result in early blossoming. (7) Moisture preceding the first blossoming always causes retardation. (8) Deficiency of moisture causes early blossoming when the daily minimum is low, late blossoming when the daily minimum is high. (9) Frosts cause a delay in the first blossoming when they do not kill. (10) Irregu- larities in the normal succession are proportionate to the difference in organization of the species concerned and to the intensity of the factors which compensate the effects of the mean daily minimum. (11) Inver- sions are extreme cases of this irregularity, and are usually the result of precipitations of moisture. (12) Plants with deep roots are less affected by drought than by moisture ; the former acts chiefly on those which do not root deeply. Protection of Plants from the Lower Fungi.*—W. O. Focke points out that plants, especially in their older portions, and during the resting periods of their active life, are little fitted to withstand the attacks of the lower fungi, and that there are certain means of protection provided them against the attacks of these enemies, which accounts for their suffering so comparatively little from them. As such, he names a firm epidermis, especially when it is protected by a coating of wax against the retention of moisture. A further pro- tection, especially to stems, is the corky layer of the bark, which, besides being itself a very resisting substance, often contains chemical matters which are injurious to the lower organisms, for example, poisons, tannin, alkaloids, and wax. The underground portions of plants, especially of those growing in marshes, secure themselves, partly by a firm epidermis, partly by means of the chemical substances named (tannin for example in Alnus and Comarum, alkaloid in Cicuta, &e.). Evergreen leaves have also, besides their protection against plant- eating animals (spines, poisonous qualities, and leathery consistence), such safeguards as are necessary against the attacks of fungi, and which again consist of a firm epidermis (Ilex), and the possession of some one or more chemicals (poison, alkaloids, &c.). The durability of the succulent fruits which serve such a distinct purpose in the propagation of plants by animals (birds), appears in many cases like- wise to have been caused by these means; while in regard to seeds, which for the most part remain dormant during the winter, either in or upon the earth, these are both protected and preserved by their stout outer covering and by similar chemical substances. Further, the author believes that the fatty oil so frequently found is as valuable for protection as for nourishment. The oil, as well as the husks, checks the absorption of water at a low temperature, without which the dry seeds cannot be attacked by the fungi of putrefaction. The volatile oils also serve in many plants as a protection against injury by the sun. When there is any scarcity of water in the soil, by their evaporation they lower the temperature; and, according to Tyndall, when these oils are present only in a small degree in the air, they * Kosmos, y. (1882). See Bot. Centralbl., xi. (1882) pp. 64-5. Ser. 2.—Vot. III. H 98 SUMMARY OF CURRENT RESEARCHES RELATING TO deprive it to a great degree of its diathermancy, so that the fragrant clouds which in a dry neighbourhood spread themselves above odoriferous plants, protect them no less from the parching rays of the sun than from nocturnal radiation. Detmer’s Vegetable Physiology.* —The second part of W. Detmer’s ‘System of Vegetable Physiology, which forms a part of the ‘Encyklopedie der Naturwissenschaften,’ treats of the following subjects :—The general properties of the growing parts of plants, and the nature of the process of growth; the phenomena of growth caused by internal conditions of growth ; the essential conditions of growth, and the influence of external conditions on growth; the natural direction of the parts of plants; and the movements of variation, that is, those which take place only in the mature parts. B. CRYPTOGAMIA. Cryptogamia Vascularia. Chetopteridee.t—M. Kuhn divides the large order of Polypo- diacexw primarily into the two groups of the smaller Chetopteride and the larger Lopidopterides. The former are distinguished by the creeping rhizome having only a single closed vascular-bundle-tube, and being covered only with delicate few-celled pales ; while the latter have an erect or creeping rhizome, penetrated by one or more fibro- vascular bundles which do not form a closed tube, and bearing scaly pale instead of hairs. The following is an analysis of the tribes :— CumrorTERIDEZ. Rhizoma repens, setosum; pales e paucis cellulis formats, quasi setee Hymenophyllacearum, basi plana affixe ; tubus fasciculi vasorum in rhizomate semper clausum. A. Sori exindusiati. Tribus I. Gymnogrammee. B. Sori indusio vero s. spurio obtecti. Tribus IJ. Lindsayee. Sori in apice nervorum gs. in ana- stomosi nervorum complurimum indusio obtecti; recep- taculum nullum ; margo immutatus, non revolutus. Tribus III. Lonchitidee. Sori semper in anastomosi nervorum, margine revoluto (indusio spurio) obtecti; indusium verum minutissimum, basi anastomosis ner- vorum affixum. Tribus IV. Microlepiew. Sori singuli apicales s. sub- apicales, margine revoluto s. indusio infero vero obtecti ; receptaculum liberum. * Schenk’s ‘Handbuch der Botanik,’ ii. (1882) pp. 447-555. Cf. this Journal, ii. (1882) p. 223. + Festschrift z. 50 jahr. Jubil. d. Konigstidt. Realschule zu Berlin, pp. 321-48 (2 pls.) 1882, See Bot. Centralbl., xii, (1882) p. 188. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. OG The genera belonging to the first tribe are characterized as follows, viz. :— GymvnogrammMes. Rhizoma repens, setosum, setis basi affixis; sori exindusiati ; petiolus rhizomate continuus; nervi apice non incras- sati (excl. gen. Cheiropleuria). A. Fasciculi vasorum petioli 1-3 ; paraphyses sporangiis admixtee s. pedicellis sporangiorum inserte. a. Sori Gymnogrammes. 1. Aspleniopsis. Sori nervorum partem occu- pantes. 2. Trichiogramme. Sori omnes nervorum partes occupantes. B. Sori coste paralleli, medii inter costam et marginem. 3. Teenitis. y-. Sori Acrostichi. 4. Platytenia. Folia pinnatisecta, segmenta maculis Doodye. 5. Cheiropleuria. Folia indivisa s, dichotoma, nervi flabellati ramis Drynarie maculis junctis. B. Fasciculi vasorum petioli 1 s. 2; paraphyses nulle; sori Gymnogrammes. 6. Psilogramme. Folia in costis nervisque hir- suta; sori e basi nervorum versus apicem decrescentes. 7. Gymnogramme. Folia glaberrima; sori apicem nervorum occupantes. C. Fasciculi vasorum petioli 2; paraphyses pauce; sori apicem nervorum occupantes. 8. Monachosorum. Aspleniopsis contains 1 species (Polynesia); Trichiogramme 11 sp. (S. America, E. Indies, Polynesia) ; Tcenitis 1 sp. (Tropical Asia to Japan); Platytenia 1 sp. (Philippines) ; Cheiropleuria 1 sp. (China, Japan) ; Psilogramme 33 sp. (S. America, Tristan d’Acunha) ; Gymno- ie 4 sp. (1 occurring in Europe) ; Monachosorum 1 sp. (HE. India, Java). Of the remaining tribes Lindsayezx includes Lindsaya (43 sp.) ; Schizoloma (25 sp.); Wibelia (3 sp.); Odontosoria (3 sp.) ; and Lind- sayopsis (3 sp.) ; Lonchitidez includes Histiopteris (2 sp.), Lonchitis (6 sp.), Pteridium (Pieris 1 sp.), Antiosorus (2 sp.), and Paesia (5 sp.) ; and Microlepiex or Dennstaedties comprises Hypolepis (14 sp.), Microlepia (15 sp.), Leptolepia (4 sp.), and Dennstaedtia (24 sp.). Development of the Spores of Salvinia.*—According to H. Hein- richer, the octant-cells in the sporocarp of Salvinia are the mother- cells of the spores, of which there are therefore only eight. The octants of one half of the archespore occupy such a position with respect to those of the other half, that the walls which separate the * SB. K. K. Akad. Wiss. Wien, Ixxxy. (1882) pp. 494-522. H 2 100 SUMMARY OF CURRENT RESEARCHES RELATING TO octants form with one another an angle of 45°. When the octants, unequal in size, separate from one another, the formation of tetrahedra commences, but not simultaneously in all the octants. The macro- spore proceeds from a tetrahedron, which is always surrounded by a clear border, like that which distinguishes the tetrahedra, and which may be attributed to the conversion into mucilage of the wall of the special mother-cells. As the sporangial capsule grows, the proto- plasmic ball, with the macrospore, becomes more and more closely applied to one of the walls of the sporangium. The macrospore now grows more rapidly, and its membrane begins to thicken, forming the exospore. The tapetal cells still always retain their nuclei. In the hardened epispore there appear more strongly refringent particles between the vacuoles, which must be regarded as the remains of the nuclei of the tapetal cells. The microsporangia form sixteen spore- mother-cells. Each of the microspores is surrounded by a clear border ; and here also the tapetal cells still retain their nuclei. Two teratological examples at this point were observed. One con- sisted of a double sporangium, which was divided in a direction at right angles to its longer diameter, each half forming its separate archespore. The other was a hermaphrodite sporocarp, containing a number of microsporangia and five macrosporangia. The author considers that the facts here recorded still further accentuate the separation of the Rhizocarpew into the two groups of Marsileaces and Salviniacew. The sexual differentiation of the sori in Salvinia must be regarded, from a phylogenetic point of view, as an advance in structure in comparison with Marsilea; the occasional hermaphrodite sporocarps of Salvinia being referable to atavism. A further evidence of advance is the formation of only eight spore- mother-cells in the macrosporangium of Salvinia, in contrast to the sixteen in Marsilea, Another indication of advance is that from this point only one spore is required in order to produce a macrospore, while in Marsilea one spore from each tetrahedron grows more rapidly, one of these then developing into the macrospore. Whether the Marsileaces or the Salviniacez is considered as the more advanced group depends on the relative importance attached to the asexual or to the sexual generation. Possibly the two are derivations from a common ancestral form. Muscinee. Structure and Classification of Muscinee.* —S. O. Lindberg publishes a succinct account of the morphology of the entire group of Musciner, including both exotic and European forms. After con- trasting the earliest stages of development with those of vascular cryptogams, he describes the germination and the protonema-stage, the root, the stem, the leaves, the “ inflorescence,” the sexual organs, the sporogonium, and finally the spore-plant, composed of calceolus, seta, theca, and spores. Under each heading, the Hepatice, Sphag- * Lindberg, 8. O., ‘Europas och Nord Amerikas hvitmossor (Sphagna) jamte en inledning om utvecklingen och organbildningen inom mossornas alla tre grupper.’ (Swedish with Latin diagnoses.) 116 pp. Helsingfors, 1882. See Bot. Centralbl., xi. (1882) p. 373. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 101 nace, and Musci are fully described, and compared with one another. In accordance with his views previously published, Lindberg considers the organs of mosses which bryologists describe as the “ flower,” to correspond, not to the flower, but to the inflorescence of flowering lants. ‘ The Hepatice are divided by the author into two sections :— Calyptra gynogena, including Lejeunia, Frullania, &c., in which the archegonia are stalked; and Calyptra thalamogena, including Ric- cardia, Lepidolena, Trichocolea, &c.,in which the lower part of the imbedded archegonium is formed from the stem, which therefore takes part in the formation of the sporogonium. In Sphagnum Lindberg is unable to detect the two kinds of spore described by Schimper; they are all of the same size. In this family he gives accurate descriptions of transverse sections of the leaves. The following is his classification of the species of Sphagnum :— J. Eusphagnum. A. Sphagna palustria (S. portoricense, imbricatum, papillosum, and palustre). B. 8. subsecunda (S. tenellum, laricinum, and subsecundum). C. 8. compacta (S. Angstroemii, molle, and com- pactum). D. §. cuspidata (S. squarrosum, fimbriatum, strictum, nemoreum (acutifolium), Wulfiz, Lindbergi, and cuspidatum, with its varieties). II. Isocladus (S. macrophyllum and cribrosum n. sp.). III. Hemitheca (S. Pylaiei and cyclophyllum). The last section should probably be erected into a distinct genus, with the following characteristics :—Foliis et bracteis fere conformibus, eisdem trunci multo majoribus quam ramorum; ramis femineis brevibus, e medio trunci egredientibus; fibris cellularum inanium valde peculiaribus. Fungi. Abnormal Hymenomycetes.*— I’. Ludwig records several instances of abnormality in Hymenomycetes, resulting from sudden alternations in growth caused by the occurrence of occasional warm dry days in a very wet season. The species in which this was noticed were Hydnum repandum, Lactarius ichoratus, Russula depallens, Cantharellus cibarius, Agaricus (Dermocybe) cinnamoneus, A. (Inoloma) amethystinus, and A. (Citocybe) laccatus. ‘They consisted mostly of secondary pilei springing from the normal pileus, sometimes of secondary stipites springing from the normal stipes; these sometimes ended in pilei, sometimes were barren. The secondary pilei were frequently of different shape from the normal one, and sometimes did not bear lamelle. Phosphorescent Agaric.t—The phosphorescent species of Agari- cini are at present limited to those the mycelium of which constitutes the different kinds of so-called “rhizomorpha.” F. Ludwig is now able to add to the list Agaricus (Collybia) tuberosus, the resting condition of which is known as “ sclerotium cornutum.” The sclerotia may either develope into mycelium, or may form the fructification direct. In the dark the mycelium of this species is distinctly * Bot. Centralbl., xii. (1882) pp. 136-8. + Ibid., pp. 104-6. 102 SUMMARY OF CURRENT RESEARCHES RELATING TO phosphorescent, resembling that of the rhizomorph-forming fungi. It is probable that other allied species may exhibit a similar phenomenon. New Ascomycetes.*—W. Voss describes two interesting new Ascomycetes, Phacidium gracile, parasitic on Lycopodium chame- cyparissus, and Leptospheria Fuckelii, on Calamagrostis sylvatica, both from the neighbourhood of Laibach. The latter occurs on a number of grasses, and is distinguished from the most nearly allied species by the peculiar form of the spores. They are nearly cylindrical, broadly rounded above, and the projecting fourth cell lies about the middle of the spore, only two rather larger cells lying beneath it. In allied species the projecting cell is the second or third (from the top), from four to seven cells lying beneath it. Its habit is that of the much more common L,. culmifraga. New Entyloma.t—P. Magnus describes Entyloma Helosciadii, a new species parasitic on Helosciadium nodiflorum, only the second species of this genus known to be parasitic on plants belonging to the Umbellifere. It is distinguished from the most nearly allied species by the small size and long form of the spores. Coremium of Verticillium.t—E. Hidam describes the formation of coremia on Verticillium ruberrimum parasitic on potatoes. They form dry feathery tufts 1-1°5 cm. long, which are swayed by the least breath of wind. From 5 to 20 fertile hyphe unite in the formation of a coremium, from which radiate on all sides well- developed filaments of spores with the characteristic verticillate branches. Exoascus.§—R. Sadebeck discusses the characters of the various species of Exoascus, which are parasitic upon, and often very destruc- tive to, different trees. He points out that the statements that the formation of the asci is not preceded by that of a mycelium, rests upon inaccurate observation. The distinct genus Ascomyces proposed by Magnus must therefore fall to the ground. There are on the alder two parasitic species of this fungus, differing very much in appearance, but resembling one another in their course of development. Sporendonema casei Desm.||—In addition to the ordinary fructi- fication of this fungus, cultivated on a decoction of dung, E. Hidam observed hitherto undescribed reproductive organs. On anastomosing mycelial cells a quantity of small protuberances made their appear- ance, which unite into rounded pseudo-parenchymatous bodies. The cells composing these bodies are filled with oil and protoplasm ; they finally swell greatly, and the cortical portion of the mass passes * Oesterr. Bot. Zeitschr., xxxii. (1882) pp. 357-9. + Hedwigia, xxi. (1882) pp. 129-30 (1 pl.). ¢ JB. Schles. Gesellsch. vaterl. Cult. Breslau, lviii. (1881) pp. 137-8. See Bot. Centralbl., xi. (1882) p. 298. § Versamml. Deutsch. Naturf. u. Aerzte zu Hisenach, 1882. See Bot. Cen- tralbl., xii. (1882) pp. 179-81. || JB. Schles. Gesellsch. vaterl. Cult. Breslau, lviii. (1881) pp. 139-40. See Bot. Centralbl., xi. (1882) p. 298. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 1038 through brown to black. After remaining for some time at rest they produce smooth oval spores with a brownish-red nucleus, which germinates, reproducing the cycle of generations. Entomophthoree.*—L. Nowakowski gives the following as the chief results of a fresh examination of this class of fungi :— The resting-spores of Hntomophthora ovispora, curvispora, and conica 0. sp., are true zygospores, the product of an undoubted act of conjugation. In the formation of the resting-spores (azygospores) of E. radicans, a transition is seen from sexual to the non-sexual reproduction of the other Entomophthoree. In Empusa Grylli (Entomophthora Grylli Fr.), on Culex pipiens, C. annulatus, and Gomphocerus biguttulus, the resting-spores are formed non-sexually, the protoplasm escaping from the cells of the mycelium and becoming encysted. The young resting-spore is then separated by a septum from the empty mother-cell, the cell-wall of which becomes rapidly absorbed. Resting-spores formed in the autumn germinated the following spring. The endospore bursts through the outer layer and lengthens into a septated hypha, which detaches with violence a conidium from its apex. A columella similar to that of Pilobolus and of Completoria com- plens occurs also in the following species :—Entomophthora ovispora, curvispora, conica, aphidis, radicans, and Empusa Grylli, but is wanting in Empusa Freseniana, n. sp., parasitic on various aphides, and in Lamia (Empusa) culicis. The author considers the Entomophthoree to belong to the Zygomycetes, and divides them into three genera:—1. Entomophthora, conjugation evident or obscure. 2. Hmpusa, conidia-bearing hyphe unbranched, resting-spores formed as described above in EH. Grylli. 3. Lamia, conidia-bearing hyphz unbranched; mycelium filiform, with organs of attachment; resting-spores formed in the apex of the hyphez, like the conidia, but the conidia are larger and spherical. The warty opaque walls of the resting-spores of Tarichium differ from those of the other Entomophthoree, hence its true position is at present doubtful, especially as its conidia are still unknown. Entomophthora rimosa Sorokin is identical with Empusa culicis A. Br. and possibly his EF. conglomerata with E. Grylli Fr. Completoria complens, described by Leitgeb t as parasitic on the prothallia of ferns, probably belongs to this group. Influence of Acids on Fermentation and on the Development of Torula.;—M. Hayduck finds that different acids have a very different effect on the production of Torula, and that their influence on the process of fermentation is not always in proportion to this. A smaller quantity generally hinders the production of Torula than its * SB. Akad. Wiss. Krakau, March 20, 1882.- See Bot. Ztg., xl. (1882) p. 560. + See this Journal, ii. (1882) p. 377. { Zeitschr. f. Spiritusindustrie, iv. (1881) p. 341. 104 SUMMARY OF CURRENT RESEARCHES RELATING TO fermenting power, while very small quantities of acid may even have a beneficial effect on both processes. This fermentation is promoted by 0:02 per cent. of sulphuric and 0-2-1:0 per cent. of lactic acid ; hindered by 0-2 per cent. sulphuric, 0°1-0°18 per cent. hydro- chloric, 0°4—0°5 per cent. phosphoric, and about 2°5 per cent. lactic acid; and altogether prevented by 0°7 per cent. sulphuric, 0-5 per cent. hydrochloric, more than 1°3 per cent. phosphoric, and more than 4°6 per cent. lactic acid. The development of Torula is promoted by 0:02 sulphuric and 0°1-0°5 per cent. lactic acid; hindered by 0-07 per cent. sulphuric and 1°5 per cent. lactic acid ; and prevented by 0°2 per cent. sulphuric and 4:0 per cent. lactic acid. Influence of Alcohol on the Development of Torula.*—M. Hay- duck has experimented on the influence on the production of Torula of alcohol itself, and of the subsidiary products of fermentation, succinic acid, glycerin, nitrogenous excretory products, and fusel- oil. The small quantity of succinic acid produced in fermentation he finds to have no injurious effect on the production of Torula ; nor does glycerin hinder fermentation, when present to the extent of 10 per cent. The nitrogenous products are also without injurious effect; while fusel-oil acts most prejudicially if present to the amount of 0°5 per cent., 2 per cent. of it entirely stopping fermen- tation. Alcohol itself hinders fermentation when present in small quantities; a proportion of 15 per cent. entirely stopping it. From 2-6 per cent. of alcohol in a saccharine solution greatly injures the development of Torula, while an admixture of 10 per cent. appears to stop it altogether. New Species of Mortierella (Mucorini).|—J. 'Therry and Thierry describe two new species of Mortierella found in gardens in the neighbourhood of Lyons, one (M. arachnoides) in hothouses, the other (M. Ficarie) parasitic on the leaves of Ficaria ranunculoides. The former is remarkable for the very rapid growth of the mycelium, the filaments lengthening as much as several metres in a single night, without branching or anastomosing. Both have an extraordinarily rapid destructive effect on their hosts, killing the leaves in the open ground in three or four days, under a bell-glass completely disorganizing them in three or four hours. Development of Mould-Fungi in the Bodies of Men and other Animals.{—T. Leber records an instance of purulent ceratitis in the eye caused by a fungus-mycelium introduced into the cornea on a glume of anoat. Experimenting on rabbits, he found that the spores of Asper- — gillus glaucus introduced into the eye in the juice of fruits germinate freely ; and equally at a temperature of 14° or of 35°-37° C. This capacity of germination in the bodies of animals appears to take place whatever the previous condition of the fungus, and independently of * Zeitschr. f. Spiritusindustrie, v. (1882) p. 183. See Bot. Centralbl., xii. (1882) p. 4. + Revue Mycol., iv. (1882) pp. 160-2 (1 pl.). + Berl. klin. Wochenschr., 1882. See Bot. Centralbl., xi. (1882) p. 317. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 105 the assistance of man. Similar experiments with Penicillium altogether failed; but this was probably the result of conditions of temperature, _ a temperature of 34°-38° C. destroying the germinating power of the spores of Penicillium. Aspergillus nigrescens, on the other hand, while thriving at the temperature of the body, did not develope in the cornea; the cause in this case being possibly its alkaline reaction. Leptothrix buccalis, which occurs abundantly in the mouth, was found to develope also in the cornea, undergoing no change from its altered conditions. The author’s experiments on this point were altogether favourable to the view of the constancy of species. Physiological Effects of various Ferments.*—Ph. Van Tieghem reports the results of a series of investigations made by M. Gayon on the influence of various ferments on different fermentable liquids. Mucor circinelloides, when vegetating without free oxygen, behaves precisely like Saccharomyces cerevisie in contact with the wort of wine or beer; the beer obtained from it being very limpid and of a ' sweet somewhat plum-like taste. But with cane-sugar this organism produces no inversion, and consequently no fermentation. But if into the liquid is introduced a small quantity of invertine, or any fungus, like Penicillium, which produces invertine, fermentation of the inverted sugar immediately sets up; and the Mucor, acting from this time like Penicillium, destroys first the glucose, and then the levulose. In the absence of the power of inverting cane-sugar Mucor circinelloides resembles M. spinosus and Mucedo and Rhizopus nigricans , and these experiments determine directly for the first time that the inversion of cane-sugar must necessarily precede its fermentation, in other words, that it is not directly fermentable. The various species of Saccharomyces behave differently in relation to cane-sugar; some, like S. cerevisic, inverting it, while others, like S. apiculatus, are wanting in this power. From these facts M. Gayon draws some applications which may be of great importance from an economical point of view; as, for example, in the separation of cane-sugar from other saccharine fluids, for example molasses. The reducing sugar may be destroyed by fermentation with Mucor, while the cane-sugar remains unaltered, and may be crystallized. He is also able to account for the reducing sugar which gradually forms in crude cane-sugar, and sometimes in that of beet. This sugar is inactive, and if this results from its essential nature the mixture ought, when fermented by Mucor, always to preserve its primitive rotation to the right. If, on the contrary, it is neutral because it consists of a compensating mixture of glucose and levulose, then, when fermented with Mucor, the power of rotating to the right ought to diminish as the glucose disappears, then to increase from the destruction of the levulose, and finally reassume its original value. Experiment favours this latter conclusion, and proves that the reducing sugar is an inverting sugar, in which the opposite powers of rotation exactly neutralize one another, * Ann. Sci. Nat. (Bot.) xiv. (1882) pp. 46-9. 106 SUMMARY OF CURRENT RESEARCHES RELATING TO Carriage of Schizomycetes through the Air.*—C. v. Nageli and H. Buchner have determined that bacteria and similar organisms are not taken up into the air simply by evaporation of the fluids in which they live, nor are they detached from a solid substratum by currents of dry air only. In order for the germs to be dispersed through the air, they must first be scattered by drops of water, and are then taken up by currents of air. This view is of importance in connection with the spread of malarial fevers. Transition between Forms of Schizomycetes.t—C. v. Nageli is of opinion that all known forms of Schizomycetes are connected by intermediate links, and that any division into species, however con- venient for the purpose of description, has no scientific value. There is no doubt that the same species occurs in widely different forms dependent on the mode in which it obtains its nourishment. Fatty Bodies as Generators of Bacteria.{—T. Brisson de Lenharée points out that fatty substances on mineral bodies or used in the hair, such as oil, pomade, glycerin, &c., attract the numerous minute germs, especially those of parasitic fungi, which abound in the air; glycerin, however, is not so deleterious in this way as the other substances named. Hence a very common source of baldness. Building and funereal stones which had been soaked in oil in order to protect inscriptions on them from the influence of the weather were found to have been much attacked by minute fungi from the very means used to protect them. Phosphorescence caused by Bacteria.$—N. Patouillard describes a specimen of Agaricus acerbus Fr. from the Pyrenees which was strongly phosphorescent. A microscopic examination showed that the phenomenon was due to innumerable bacteria allied to Bacterium catenula Eh., mobile and colourless, composed of a variable number of cylindrical rods placed end to end, forming a straight or curved chain. They were accompanied by a great number of another organism allied to Saccharomyces, consisting of a hyaline refringent globule, often with a brilliant point in its centre, which increased by gemmation after the ordinary manner of a torula. Both of these organisms were found at a considerable depth in the tissue, as well as near the surface. The phosphorescence of fungi is therefore due to two causes: first, to the action of oxygen on the tissue of the fungus itself, as in the case of Agaricus olearius, rhizomorpha, and exotic luminous species; secondly, to the accidental presence of parasitic luminous organisms. Inoculation of Tuberculosis through Respiration.||—In order to ascertain whether the germs of tuberculosis, if present in the air, can * Med. Centralbl., xx. (1882) p. 513. See Naturforscher, xv. (1882) p. 364. Unters. iiber niedere Pilze aus dem pflanzenphysiol. Instituts Miinchen, i. (1882) pp. 129-39. . t Actes du Congres de la Rochelle, Sect. Bot., 1882. See Rey. Mycol., iv. 1882) p. 249. . § Rey. Mycol., iv. (1882) pp. 208-9 (1 pl.). || Comptes Rendus, xciy. (1882) p. 1391. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 107 be inhaled by respiration, Giboux prepared two boxes, in each of which he placed two young rabbits, and passed daily through each of them 20,000-25,000 c.c. of air, which had been exhaled by phthisical patients of the second and third degree. With one of the boxes the air was first filtered through a wad of cotton-wool. After about three and a half months, the rabbits in the unprotected box died, having suffered loss of appetite, thirst, diarrhcea, &c., and the lungs, liver, and spleen were found to be tuberculated. In the protected box, on the contrary, the rabbits were still perfectly healthy, and on autopsy not a trace of tuberculosis was to be found. Parasitic Myxomycetes.*—W. Zopf describes a new myxomycete, Haplococcus reticulatus, belonging to the Monadinea, and specially to the Vampyrellez, which settles in great quantities in the muscles of swine. Its structure is extremely simple, exhibiting two stages of development, sporangia and resting-spores. The sporangia are globular, and their membranes are thin in places where the delicate inner wall protrudes in the form of papillez. The protoplasmic con- tents break up into portions which display amceboid motions, and finally escape as amcebz through the gelatinized papille. The resting-spores are globular or tetrahedral with rounded corners, re- sembling the spores of some ferns. Their strongly thickened and cuticularized membrane is marked with ridges which form a beautiful network. The author has not determined whether the parasite has an injurious effect on the host, or renders its flesh unfit for food. Alge. Marchesettia, a New Genus of Floridex,{— Under the name Marchesettia spongioides, F. Hauck describes a new type from Singapore, Madagascar, and New Caledonia, belonging to the Areschougiacezx., The thallus is spongy and cartilaginous. The reproductive organs are placed on special fertile branches, which are sometimes scattered over the thallus, but more often collected into tufts at the apices of the branches, and are formed from the growth of the outer branches of the filaments of the thallus. The fertile have the same structure as the vegetative branches, but in their fertile portions the cells of the outer layers are considerably smaller. The cystocarps are sessile on the fertile branches, broadly ovate, with moderately thick cellular pericarp open at the apex, which incloses a simple or lobed roundish nucleus, composed of a large, branched, basal, placental cell, the peripheral branches of which radiate into crowded tufts of branched segmented carpogenous filaments, the upper cells of which become carpospores. The tetrasporangia are formed in somewhat club-shaped fertile branches, the upper portion of which is swollen into a nemathecium, which developes, by the growth of the cortical cells, into short rows vertical to the surface; between these are placed the longish, very irregularly divided tetrasporangia. * SB. Bot. Ver. Prov. Brandenburg, 1882, pp. 55-6. + Hedwigia, xxi. (1882) pp. 140-1. 108 SUMMARY OF CURRENT RESEARCHES RELATING TO Chromophyton Rosanoffii.*—N. Wille found, associated with Conferva, Orthosira, Spirogyra, and Mougeotia, a brown palmella-like organism which he identified with Woronin’s Chromophyton Rosanoffii.t As described by the discoverer, he found two kinds of zoospores, one smaller and rounder, the other larger and ovoid, each with a single cilium. After swimming about, they attach themselves by the anterior ciliated end to a filamentous alga, and become encysted ; the encysted form contains a red eye-spot, and again developes zoospores. The organism which proceeds from the ovoid zoospores is identi- fied by Wille with Ehrenberg’s flagellate Epipyxis utriculus, and the one which proceeds from the spherical zoospores with Stein’s flagel- late Chrysopyxis bipes. He concludes therefore that Chromophyton Rosanoffii is not an independent organism, but that it must be regarded as a palmella-form of two flagellate Infusoria. Phyllosiphon Arisarit—F’. Schmitz has undertaken a fresh ex- amination of this organism, parasitic in Italy on the leaves of Arisarum vulgare ; his results differing in some respects from those already obtained by L. Just.§ The thallus of the parasite spreads extensively through the inter- cellular spaces of the parenchyma immediately beneath the palisade- parenchyma of the leaf; and in these spaces the filaments branch normally and almost invariably dichotomously, lateral branches being very rarely seen. Their average diameter is from 25 to 385 ~; when the apical growth has ceased they increase in diameter to about 60 p, and the formation of spores commences. The filament dichotomises repeatedly, and thus becomes changed into a more or less ramifying tuft of branches of equal or unequal length, which are sometimes swollen into a club-shape at the extremity. The spores then begin to be formed in the interior. This portion is, however, never separated from the rest of the thallus by a septum. The vegetative and the spore-forming stage of the thallus are not sharply separated the one from the other. The wall of the filament is simple at the growing extremity, double in the older parts, the outer layer being cuticularized. The growing apices of the filaments contain a parietal layer of protoplasm, with strings of the same substance crossing the central cavity, and containing drops of oil. The protoplasm contains a number of nuclei of irregularly spherical or lenticular form, each of which has usually a nucleolus; the nuclei increase rapidly by division. In the growing apices the protoplasm is completely colourless, but further backwards it gradually assumes a yellowish green and ultimately green colour. This is not due toa general colouring of the entire protoplasm, but to a number of excessively minute disk- shaped chlorophyll bodies dispersed through it. It contains also a number of globular starch-grains, which vary greatly in size, and * SB. Bot. Ver. Prov. Brandenburg, 1882, pp. 49-50. + See this Journal, i. (1881) p. 100. ~ Bot. Ztg., xl. (1882) pp. 523-30, 539-55, 563-73, 579-83. § See this Journal, ii. (1882) p, 31. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 109 differ in some of their reactions from ordinary starch, and may possibly be sphero-crystals. The entire protoplasm of the filaments from the apex to the base of the last branch is used up in the production of the spores, with the exception of the outermost parietal layer, which remains behind between the spores. This always results from a small mass of proto- plasm surrounding one of the small nuclei and containing a single disk-shaped chlorophyll body becoming separated off to an independent existence. These are rapidly inclosed in a membrane, and become the ellipsoidal spores, which contain a colourless homogeneous proto- plasm, a single chlorophyll-disk attached to one of the longer walls, a nucleus, and drops of oil. The spores vary greatly in size, the average length being from 2-6, and the average breadth from 1:5-2°5 yp. The inal spores escape in vast numbers in a dark-green mucilage to the surface of the leaf, the outer layer of the wall of the filaments bursting in consequence of the eager absorption of water by the inner layer. Some, however, remain within the filaments, where they show the first indications of germination. Further stages of germination were not observed. With regard to the systematic position of Phyllosiphon, Schmitz is disposed to place it in or near the Siphonex. It differs, however, essentially from Vaucheria in the mode of reproduction and of forma- tion of the spores, and displays greater affinity to Udotea; Holimeda, and some allied genera. From the latter it differs chiefly in the spores being inclosed in a membrane and motionless instead of being naked and biciliated. Argentine and Patagonian Algw#.*—O. Nordstedt has examined algee sent by Professor G. Hieronymus from the Argentine Republic and Patagonia, some of which were found in the neighbourhood of Cordobas, in the Cordilleras of the province Rioja, and in the Sierras Famatina and Velasco; while others were collected by P. G. Lorenz and G. Niederlein on the military expedition of the Argentine General Roca to the Rio Negro. Thirty-seven kinds are determined, belonging to twenty-three genera, besides undetermined kinds (mostly sterile Zygnemacex) belonging to seven other genera. The following are the new forms:—Penium conspersum, Wittr. 8 americanum, with four chlorophyll-masses as in P. interruptum; Cosmarium gemmiferum Bréb., a form which resembles C. Quasillus ; Tolypothria penicillata (Ag.?) Thuret, 8 gracilis, and some other forms differing but slightly from the European. The alga-flora of the countries in question agrees very closely with the European, there being only three kinds which do not also appear in Europe: Huastrum quadratum Nordst., Vaucheria Hookeri Kitz., and Batrachospermum (Dillenii var.?) Puig- garianum Grun. Swedish Pediastreze, Protococcacee, and Palmellacex.j—G. Lagerheim describes 68 species, belonging to 29 genera, of alge from * Bot. Notiser, 1882, pp. 46-51. t_Ofversigt af kongl. Vetensk.-Akad. Férhandl. (1882) pp. 47-81 (2 pls.). See Bot. Centralbl., xii. (1882) p. 33. 110 SUMMARY OF CURRENT RESEARCHES RELATING TO the Hammarby lake and neighbouring rocks at Danviken near Stock- holm, of which several species and varieties are new. He gives also general critical remarks on the families named above. The genus Scenedesmus is divided into two sections, the first of which belongs to the true Pediastres, while the second is nearly allied to some species of Palmellaces, as Raphidium and Selenastrum. The following are given as their characters :—Sect. I. Obtusi. Cellule utroque polo plerumque obtuse vel rotundate. Ccenobium filiale ruptura membrane cellule matricali liberum fit. Membrana cellu- larum adultarum, cum membrana specierum Sectionis II. com- parata, subcrassa. S. béjugatus, radiatus, alternans, denticulatus n. sp., aculeolatus, Hystriz nu. sp., dispar, and quadricauda. Sect. II. Acutz. Cellule utroque polo plerumque plus minusve acute. Propagatio incerta. Membrana cellularum adultarum cum membrana specierum Sectionis I. comparata, tenuis. S. attenuatus and obliquus. The diagnosis follows of Actinastrum, a new genus of Palmel- laceze :—Cellule fusiformes, rarius fere obclavate vel cylindrice, a centro communi radiatim exeuntes, familias quadricellulares vel octo- cellulares, libere natantes, fermantes. Propagatio divisione succedanea cytioplasmatis cellularum fit, et familia filialis eo modo formata ruptura membrane cellule matricalis libera fit. Zoospore ignote. Only species A. Hantzschii; long. cell, 10-24; crass. 3-6 p. The previously unknown mode of reproduction of Selenastrum is thus described. In S. acuminatum n.sp. the cell-contents first divide lengthwise into two halves, the two daughter-cells again dividing by an oblique wall. These four cells sometimes directly constitute themselves into a new ccenobium, but usually only after another division, in which case either the whole eight cells may form a new ccenobium after the bursting of the membrane of the mother-cell, or they may constitute two ccenobia of four cells each. Selenastrum forms a connecting link between the Pediastrez and Palmellacee. In Urococcus insignis Kiitz., (Chroococcus macrococcus) B ferru- gineus Lagerh., neither the stipes nor all the integuments of the cell are coloured blue by chlor-iodide of zinc, but usually only the inner- most of the latter. The formation of new ccenobia of Dictyospherium reniforme takes place by each mother-cell dividing by repeated bipartition into eight daughter-cells, all the membranes of the original ccenobium and of the stipites being absorbed. In D. Ehrenbergianum and pulchellum, on the contrary, the mother-cells only divide into four daughter-cells arranged in a cross, which then separate, and finally form new ccenobia by repeated bipartition. Crenothrix Kihniana as a Contaminator of Water.* — The water which supplies Lille, from the springs at Emmerin, having become undrinkable in consequence of a red deposit and foetid taste and smell, was found by A. Giard to be infected with Crenothria Kiihniana, which precipitates oxide of iron from aerated water. He found the microgonidia formed by transverse division in the sporangia * Comptes Rendus, xiv. (1882) p. 247. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 111 or terminal swellings of the filaments to be endowed with active movement by means ofa cilium. From the gonidia was developed an irregular merismopodia-form, which soon passed into a zooglcea-like mass, and finally into regular cylindrical tubes of different lengths. The palmella-form described by Zopf he regards as a different organism belonging to Ascococcus. The only remedy he believes to be filtering ; but recommends that the water for the supply of large towns should be obtained from deeper sources, and from springs free of salts of ferrous oxide and far removed from industrial establishments. Alga parasitic on a Snake.*—P. Magnus describes, under the name Cladophora (Spongomorpha) ophiophila, a fresh-water alga found on the Siamese fresh-water snake, Herpeton tentaculatum. The dark- green plant branches profusely, three branches nearly in one plane springing from each node. From the lower cells of the main stem and of the lower branches spring unicellular fibres, which serve as organs of attachment, and enable the plant to resist the water through which the snake swims. Associated with the Cladophora is a characteristic vegetation consisting of a number of diatoms, a Chamesiphon and a Ulothrix. Structure of Diatoms.j—M. W. Prinz replies to the objections made by Mr. Deby, Count Castracane, and Prof. A. Grunow (Vol. I. (1881) pp. 508 and 509, and II. (1882) p. 246), to his view of the perforation of the valves of the species of diatoms examined by him in thin rock sections. He considers that his objectors have drawn their principal argu- ments from facts observed in different conditions and from the exami- nation of species different from those which he described. He agrees, however, that there are many species which present details of structure which teach nothing in regard to the conformation of other species of similar appearance. The details of the structure of Pleurosigma angulatum, for instance, are too complicated and delicate to decide the question. The thinnest sections of this species always comprise at least two rows of pearls or pores. The siliceous membranes which contain these details will give in section the image of two continuous lines, one inner and the other outer. It is this which causes Dr. L. Flégel t to maintain the existence of chambers closed by these membranes. This image is produced with all the sections, even those of the large species; but this aspect disappears when the section is sufficiently thin and it is examined by high powers. We then see that the black lines repre- senting the membranes are discontinuous, and cut by bright lines which correspond to the openings. To study these details the thin- ness of the section must have relation to the fineness of the markings to be resolved. The greater part of the beautiful work of Dr. Fligel has been put in doubt by the observations of Miiller,§ who has shown * SB. Ges. naturf. Freunde Berlin, June 20, 1882. See Bot. Centralbl., xii. (1882) p. 75. t Bull. Soc. Belg. Mier., ix. (1882) pp. 23-7, t Arch. f. Mikr. Anat., vi. (1870) p. 472. § Bot. Ztg., 1872, p. 242. ah SUMMARY OF CURRENT RESEARCHES RELATING TO that the sections of the former were too thick, and that the closed chambers which he described must be open, as they were filled up by the immersion in balsam. Miiller, however, only admits an aperture on the outer side. Impressions on collodion do not appear to have given the results expected by the authors who employed it. On the other hand, the submersion of the valves has equally furnished facts which are wanting in concordance. Photographs, again, give only illusory diffraction images, and the suggested examination of the valves by reflected light cannot oliminate these errors. To show the difficulty of these investigations it is sufficient to recall the fact that the parts which are much less delicate, such as the con- nective, the raphe, and the nodules, still give rise to very diverse inter- pretations. M. Prinz thinks that these divergences originate in great part from the want of distinctness in the sections obtained by cutting diatoms contained in a medium without consistency, such as gum arabic. The author is about to re-examine some diatomiferous rocks with the assistance of Dr. Van Ermengem. —+>——. MICROSCOPY. a. Instruments, Accessories, &c. Boecker’s Air-pump Microscope.—E. Boecker, of Wetzlar, manu- factures the air-pump Microscope shown in Fig. 7, which enables an object to be examined in a vacuum under the Microscope, and the progressive effects at- tendant upon the exhaustion - of the air watched, as well as serving for the more ordinary purposes of an air-pump in mounting. The apparatus is secured to the table by the clamp A, and the piston of the pump B is put in operation by the handle C acting on a rack and pinion D E. The chamber F (22 x 3 in. deep), in communication with the pump, is pierced with a central aperture which is closed by a piece of glass, allowing the light from the mirror G to reach the object placed in the chamber. The latter is made air-tight by a circular glass plate greased at its margin. H is the tap for readmitting the air. Hither a simple or a compound Microscope can be attached “Dhaf Li ese ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 113 to the arm I, and the object observed while the chamber in which it is placed is being exhausted.” Improved Griffith Club Microscope.t — The original “ Griffith Club Microscope” was described in Vol. I. (1881) p. 293. Since that time important changes have been made by Mr. EH. H. Griffith, so that very little of the original form is left, as will be seen on comparing figs. 8 and 9 with the earlier illustrations. It retains its original Fic. 8. Ty “name in appreciation of the honour conferred on the inventor by the “ Griffith” Clubs of Detroit and Danville, U.S.A. It is a full-sized * Since the above was in type we observe that a nearly identical instrument is described by Dr. L. Dippel (in ‘Das Mikyroskop,’ 2nd ed. 1882, p. 685, fig. 496) as made by Zeiss. + Proc. Amer. Soc. Micr., 5th Annual Meeting, 1882, pp. 149-52 (8 figs.). Ser, 2.—Votu. III. I 114 SUMMARY OF CURRENT RESEARCHES RELATING TO instrument and the main and draw tubes have the Society screw. The coarse adjustment is effected by rack and pinion on the “Jackson” principle, and has about 3 in. of motion. The fine adjustment, which appears to be both simple and efficient, is effected Fig. 9. fs ont by the application of a worm-wheel and tangent-screw to the axis of the pinion of the coarse adjustment. The worm-wheel is on this axis, near the limb, and it is acted upon by the tangent-screw being sprung against it, the milled head of which is shown behind the limb in fig. 8. When the coarse adjustment is in use, a “snail”-shaped Pléssl’s models. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. ts lever on the right of the limb (handle shown beneath the large milled head) forces the tangent-screw from contact with the worm-wheel, a spring latchet locking it in position. By releasing the “snail” lever the tangent-screw is pressed into the worm-wheel, and acts upon the coarse adjustment so slowly that objectives of high power can be focussed with it. It will of course be understood that when the Fic. 10. No COOOL Mena ia | , iil ~ aes con ie tangent-screw is sprung against the worm-wheel the coarse adjust- ment is no longer operative, which Mr. Griffith considers to be a pro- tection against breakage of slides. A similar system of fine focussing was adopted in England many years ago, and is still used in some of The stage clips are supported on a bar above the stage, allowing the slide to make almost a complete revolution. The r 2 116 SUMMARY OF CURRENT RESEARCHES RELATING TO mirror-bar is adjustable in length, and the mirror can be set at any angle above or below the stage, allowing any obliquity of illumina- tion for opaque and for transparent objects. The standard divides midway between the body and the foot, and the base may be detached, and the body set on an extra standard (fig. 9), with a screw at the end for fixing it in a tree, laboratory table, &e. The base being inverted and placed on a spindle, which is always in position in the box, becomes a turntable, provided with self-adjusting clips for holding the slide. Three rods, with silvered balls at one end, are the supports for the Microscope, and they give momentum to the turn- table when in use. Two small holes in the edge of the turntable foot allow the attachment of an adjustable lamp-holder, which is furnished with a lamp for class, lecture, and exhibition use. >> <=> wy uy borders of the separate partial images should not show any other tints than a very narrow edging of pure green, rose, or violet of the secondary colours of a spectrum. Spherical aberration is revealed, when, with the best focussing, the clear lines Fic, 19 appear as if immersed in the middle of a broader ae foggy streak, or when two images, more or less overlapping each other, merge on altering the focus, into one image, somewhat broader and more misty. A short and ready method of testing ap- proximately any objective is recommended by Professor Abbe, as it is applicable to all instru- ments without requiring any apparatus except the test object already described. This may be briefly explained as follows :— First, focus the test plate with central illuminating rays, then withdraw the eye-piece, and turn aside the mirror so as to give the utmost obliquity of illumination, which the objective under trial will admit of. This will be best determined by looking down the tube of the Microscope whilst moving the mirror, and observing when the elliptic image of light reflected from it, reaches the peri- pheral edge of the field. As soon as this is done, replace the eye-piece, and examine afresh the object plate without altering the focus. If the objective be perfectly corrected, the groups of lines will be seen with as sharply defined edges as before, and the colours of the edges must, as before, appear only as those of the secondary spectrum in narrow and pure outline. Defective correction is revealed when this sharp definition fails, and the lines appear misty and overspread with colour, or when an alteration of focus is neces- sary to get better definition, and colours confuse the images. A test image of this kind at once lays bare in all particulars the whole state of correction of the Microscope; it being of course assumed that the observer knows how to observe and what to look for. With the aid which theory offers to the diagnosis of the various 126 SUMMARY OF CURRENT RESEARCHES RELATING TO aberrations, a comparison of the coloured borders of the separate partial images, and an examination of their lateral separation and their differences of level, as well in the middle as in the peripheral zones of the entire field, suffices for an accurate definition of the nature and amount of the several errors of correction, each of them appearing in its own primary form. Therewith we also see that which arises from aberration, properly so called (faults of focussing function), clearly separated from such imperfections or anomalies as spring from mere differences of amplification between unequally con- verged and unequally refracted rays; and moreover we eliminate completely all influence of the ocular on the quality of the image. Hardy’s Chromatoscope.—Mr. J. D. Hardy describes a method of illumination by an instrument (figs. 20 and 21) which he calls the “ Chromatoscope ” :—“Its chief purpose is that of illuminating and defining objects which are non-polarizable, in a similar manner to that in which the polariscope defines polarizable objects. It can also be Fie. 21. Sp. Spot lens in its tube St. Ch. Chroma- The letters indicate the disposition toscope glass plate resting on the of the blue, red, and green stained inner flange of the tube A. glass. applied to many polarizable objects. This quality, combined with the transmission of a greater amount of light than is obtainable by the polariscope, renders objects thus seen much more effective. It is constructed as follows:—Into the tube of the spot lens (fig. 20) a short tube is made to move freely and easily. This inner tube has a double flange, the outer one (which is milled) for rotating, and the inner one for carrying a glass plate. This plate (fig. 21) is made of flat, clear glass, and upon it are cemented by a very small quantity of balsam, three pieces of coloured (stained) glass, blue, red, and green, in the proportion of about 8, 5, and 3, as shown in the figure. The light from the lamp is allowed to pass to some extent through the interspaces, and is by comparison a strong yellow, thus giving four principal colours. Secondary colours are formed by a combination of the rays in passing through the spot lens. The stained glass should be as rich in colour and as good in quality as possible, and a better effect is obtained by three pieces of stained glass than by a number of small pieces. The application of the chromatoscope is almost unlimited, as it can be used with all objectives up to the 1-8th. Transparent objects, ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 127 particularly crystals which will not polarize, diatoms, infusoria, palates of molluscs, &c., can not only be seen to greater advantage, but their parts can be more easily studied. As its cost is merely nominal, it can be applied to every instrument, large or small, and when its merits and its utility by practice are known, I am confident that it will be considered a valuable accessory to the Microscope.” Gundlach’s Substage Refractor.—E. Gundlach publishes direc- tions (with a table) for using this apparatus for the determination of the aperture of objectives from 1:13 N.A. to 1:51 N.A. (97° to 180° in crown glass). The refractor (described Vol. II. (1882) pp. 692 and 860) consists of a small cube of glass, having one blackened and several polished surfaces. To use it, screw on the objective, and in place of the eye-piece, put a diaphragm having an opening about 1-4th in. in diameter. Then to the front surface of the objective, with a very small drop of Canada balsam, make the refractor adhere by that surface which is opposite the blackened one, in such a position that the two polished side surfaces will stand vertical when the body is brought into a horizontal position. Let the balsam harden a little; place the body in a horizontal position, and turn the mirror to one side to get it out of the way. Then place two lights—flat-wicked oil lamps are best—at some distance from the Microscope, say six or eight feet, one on each side of the optical axis, and at first pretty near this axis. By looking through the diaphragm at the eye-piece end, towards the objective, the two lights will appear there as two small light-spots, presuming the angle of the objective to be large enough. If they do not appear, and also will not, or at least one of them, when the lights are brought very near together, then the angle of the objective is smaller than 96° or 97° in crown glass, according to the index of refraction of the crown glass used in the refractor ; and the angle cannot be determined with it. If they appear, move both lights slowly away from the axis and find carefully the place for each where its image in the objective will just disappear. Determine the angle described by the light-rays entering the refractor at each side from each lamp, either by measuring directly, or by measuring the distance of the lamps from each other and from the refractor, reducing the distance of the lamps by the thickness of the glass cube, and finding from these three measure- ments, as the sides of a triangle, the desired angle by calculation. Compare the angle thus found with those given in column A of the table, and find the one which is nearest to the determined angle. The corresponding angle of column B is the crown-glass angle of the objective, and the corresponding number of column C is its numerical aperture. The balsam may be removed easily and safely with a little benzine. Tolles’ Frontal-prism Illuminator.—Fig. 22 shows an arrange- ment devised by Mr. R. B. Tolles to be applied to the front of a 1-in. objective for illuminating opaque objects. 128 SUMMARY OF OURRENT RESEARCHES RELATING TO The segment of a plano-convex lens A has a curvature of 0:4 in. radius, and for convenience of mounting, the segment is somewhat longer than is optically necessary. To it is cemented an equilateral prism from which the greater portions of the basal angles have been cut off so as to leave only a small part of the original form of the prism at the apex B. The dimensions of the prism are :— Total length Boer Po, so Oe Oeeure Upper reflecting face... .. .. vin Surface of emergence... .. .. ‘075 ,, Mpiickness i st ae ee, | oe Breadth Sas De oars 2 NS The lens condenses the rays upon the upper internal face of the prism, whence they are totally reflected and Fic. 22, pass with slight refraction through the lower prism-face in the direction of an object placed under the centre of the front lens of the ob- | | jective. SS Mr. Tolles states that by this arrangement the effective aperture of the object is not A reduced, as the apex of the prism is placed AS just outside the cone of rays which the ob- jective transmits from the object. Such a device seems hardly needed for so low a power as 1 in., but it would be interesting to know if the plan can be successfully used with higher powers. Warm and Moist Stages—Dr. R. L. Maddox describes several forms of these stages which he has devised. A slab of ebonite 84 x 24 x 3 in. has a central hole 5-8ths in, in diameter, slightly countersunk on the under side (fig. 23), into Fig. 23. which is cemented a circle of stout cover-glass. On the upper side a deep groove is cut at about 1-12th in. from the aperture, 1-8th in. wide, and 3-16ths in. deep; another deep groove concentric with the former being turned out 1-12th in. from it, about 3-16ths in. wide and 5-16ths in. deep. Two holes are drilled through one end of the slab, 4 in. apart, ending in the outer groove. At the opposite end of the slab either a deep well is sunk to hold a small circular thermometer, or a hole is drilled through the end of the slab reaching nearly to the outer groove, to hold a clinical thermometer. The opposite holes have two small brass tubes 1} in. long screwed into them and cemented air-tight. Three screws, furnished with rather wide thin screw nuts, are screwed into the base-plate, one between the ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 129 two drilled holes and 6-8ths in. from the edge of the base-plate, the two others at 6-8ths in. from the opposite end and 5-16ths from the sides; the screws project through the top of the plate about 3-16ths of aninch. This completes the base-plate. The top-plate consists of a stiff thin plate of brass, 22 in. long by 21 in.. wide, with a central aperture of } in. countersunk or bevelled on one side, which forms the upper surface; three holes are drilled to permit the three screws to pass through, and if the circular thermometer be preferred a portion of the edge is cut away, half-moon shape, to permit of easy reading of the small thermometer. To the non-bevelled surface is cemented a thin circle 5-8ths in. wide; a plain ring of brass, which will drop easily into the middle of the imner groove flush with its upper surface, is soldered on to the under surface of the top-plate. This completes the top-plate, which should be platinum blacked. In use the top-plate is turned over, under surface up. On the thin cover is put the droplet, with the objects for study, and, if required, a very thin, small circle of mica or thin cover-glass is placed carefully upon it, which will adhere by capillary attraction. An indiarubber flat band, with an aperture that will just pass over the brass ring without undue stretching, is put on, the width of the band or a little sheet of pure indiarubber extending to the side edges of the top-plate. If the observation is likely to be carried on for any time, a little olive- oil or glycerine, or even water, is placed in the narrow groove, into which the ring fits easily. To the two tubes in the base-plate are attached two narrow indiarubber tubes about 8 in. long, into the opposite ends of which are fixed two glass tubes, drawn out at the free ends into almost capillary orifices. _The cover ready prepared is now put on the base-plate, the brass ring dipping into the fluid in the inner groove forming an air-tight trap, the nuts are screwed on to the three screws and pressure made on the top-plate, so as to render, by means of the wide flat band of indiarubber, the whole water-tight. A piece of thick grey or drab cloth, with a central aperture 3-4ths in. or 1 in. in diameter punched out of the centre, is placed on the stage of the Microscope, and on it is arranged the warm stage. A vessel containing hot water is supported on a tripod at one side or in front of the Microscope ; one of the tubes is put into it, reaching to the bottom; the end of the other tube is placed in the mouth and the water sucked through, and is then turned down into a vessel to receive the water that passes round the outer groove, the rate of discharge being in relation to the length of the lower limb of the siphon and the entering orifice for the flow of hot water, as in Professor E. H. Bartley’s plan.* To ensure the water flowing round the groove, it is best to place a partition in the outer groove between the two drilled holes for the brass tubes. The water in the vessel may be maintained at any required heat up to the boiling-point by means of a lamp or gas flame, but if kept steadily at 160° Fahr. the thermometer indicates a temperature of about 92° Fahr. Should plenty of moisture be * See this Journal, i. (1881) p. 672. Ser. 2.—Vot. III. K 130 SUMMARY OF CURRENT RESEARCHES RELATING TO required, a narrow strip of blotting-paper can be damped and placed round the central hole, making it adhere to the sides. Another form (fig.24) consists of a hollow ring of brass, 13 in. external diameter, the tube of the ring being about 1-4th in. outside diameter. A saw-cut is made almost through the ring, and into it is soldered a partition plate. On each side, about 1-4th in. from the partition, two holes are drilled into the tube, and into each is soldered a fine brass tube; at the opposite side of the ring is soldered another tube, closed at the end that is fixed in the ring. Into this, when in use, is placed the end of a small clinical thermometer. Indiarubber tubes are attached to the two brass tubes, as in the former, terminating in glass tubes with small orifices. Two flat plates of thin ebonite are also required, with central apertures of the same diameter as in the previous forms, the bottom one having its aperture closed with a stout cover circle, and the upper one with a thin cover circle cemented to the inner surface. To use the ring-stage, place a narrow ring of damp blotting-paper on the upper surface of the bottom plate, then a flat ring of india- rubber ; upon this carefully put the brass ring (which has its upper and under surface slightly flattened on the lathe), and on the top, place a similar indiarubber band; then, having put the material to be examined on the under surface of the thin cover, either protected with mica or otherwise, turn it over upon the indiarubber ring on the brass ring, and bind the two ebonite plates together by two stout indiarubber bands. This is then used in the same way as the former, the tempera- ture obtained being very similar; the thermometer is placed at any part of the upper plate, but preferably on the part over or between the two brass tubes. The brass portion of this form may be put to another use. Toa thin ebonite plate with a central aperture (fig. 25) is cemented and Fic. 24. Fig. 25. pinned a circular ebonite block of the same thickness as the ebonite stage of the first form. In the block is turned a central aperture wider at the base than at the top, which is slightly countersunk, and ZOOLOGY AND BOTANY, MICROSCOPY, ETC. It into it is cemented a small cover circle; round the central aperture is turned concentrically a deep groove to form an air-space, and into which a moistening thread can be placed if required. A brass cap with milled edge and central aperture has cemented to the inside, over the aperture, a thin circle cover, and on this the object is to be placed. Over the outside of the circular ebonite block is slipped a thin, narrow indiarubber ring; the brass cap must fit correctly over the ebonite block, the ring of the cap closing upon the indiarubber ring, making the whole air-tight, and bringing the free surface of the droplet of liquid to touch the surface of the small glass circle, in a similar way to the ordinary live-box. The brass ring warm stage is now placed over the circular block of ebonite. In this way it is found, if care be taken, that the circular thermometer placed on the thin cover indicates 90° Fahr. without the water boiling, and if protected from cooling by cloth above and below, the temperature can be equably maintained. ‘Another plan is to employ two thin ebonite plates 3 by 13 in., pierced with apertures about 5-8ths in. bevelled on one side; each is closed with a thin cover circle, one is used as the base-plate, the other as an ordinary slide. The object is put on the cover; upon this is gently placed a very thin cover-glass about 7-16ths in. in diameter ; one or two small indiarubber bands are placed flat on the lower plate, the upper one is reversed over them, and the two are - bound together by two indiarubber rings. An air-tight space is thus easily made, and if it be desired to add moisture, a thin circle of damp blotting-paper can be placed within the rings, or if between them, the edge of the ring of paper may project and be moistened as required ; but the pressure from the bands must not be too great. If increased temperature be required, the whole can be put on the brass ring stage without trouble. Dr. Maddox does not claim that there is much novelty in these different forms, but he believes they differ somewhat from any de- scribed, and may prove useful in the study of minute organisms, which has so largely developed within the last few years. Dibdin’s Hot Stage.*—Mr. W. J. Dibdin also describes a form of “Hot Stage” in which simplicity is probably carried to its furthest limit. It consists only of a square white glass bottle resting on the stage (which must be inclined 45°). In its cork is a thermometer and two siphon tubes, one serving as a waste-pipe and the other communicating (by a piece of indiarubber tubing) with another siphon-tube in the cork of a flask, which is kept heated on a tripod ~ over a spirit-lamp, and also has a thermometer. A constant stream of water is thus kept flowing through the bottle on the upper side of which the object is placed. Mr. Dibdin used the apparatus for observing the bursting-point of starch cells. Caton’s Fish-trough. — This (fig. 26) consists of an oblong or slightly conical box of ebonite, closed at one end and large enough to hold the body of a minnow or stickleback very loosely. This box is attached to a plate of ebonite, which can be placed on the stage of the * Journ. Post. Mier. Soc., i. (1882) pp. 177-8 (1 fig.). K 132 SUMMARY OF CURRENT RESEARCHES RELATING TO Microscope. The tail of the fish covers an aperture in the plate closed with a piece of glass, and it is held securely in its place by a ligature; the caudal fin, which rests on the glass, is further secured by a couple of springs. The box itself, which incloses the head and Fic. 26. Mh HV ib : | | | | gills of the fish, contains water which is constantly renewed by means of two tubes, the upper of which, guarded by a screw-clamp, com- municates with a vessel at a higher level, the lower conveying the water away as fast as it is supplied. The stage must be inclined at an angle of about 40°. “The excellency of this method” (according to Prof. J. Burdon-Sanderson *) “lies in the fact that the animal can be kept under observation, without the use of any narcotizing drug, for a long time in a perfectly natural condition.” Dayton’s Modification of the Wenham Half-disk Illuminator, Dr. R. Dayton, being convinced that the improved resolution of the markings upon diatoms, when the V-shaped diaphragm was used, consisted not so much in its cutting off the less oblique pencils of light reflected from the mirror, but in the total exclusion of the dif- fused rays emanating from the source of illumination, describes a modification by which the benefits arising from the use of the Wenham half-disk are combined with those of the Woodward prism and V diaphragm in a single apparatus. A brass slide, 8 in. by 1 in., A A (fig. 27, under-view; fig. 28, vertical section), has a circular bevelled opening, in which a corre- spondingly bevelled brass disk B fits from above. Two latchets F F are attached to the under surface of the disk, and allow it to rotate freely in its bed without slipping out of the slide. In the disk B is an opening exactly fitting the illuminator D. Dr. Dayton proposes to cut away a portion of the lenticular edge of the latter, leaving a * ‘Handbook for the Physiological Laboratory,’ 1873, p. 229 (1 fig.). In the fig. the shape of the box differs slightly from that in our text. + Proc, Amer. Soc. Mier., 5th Ann. Meeting, 1882, pp. 161-3 (3 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 133 plane face H (fig. 27) on one side, through which parallel rays making an angle of 68° with the optic axis may be transmitted without con- densation, as in Woodward’s prism. A swinging shutter-diaphragm H, of blackened brass, forming a shell-like quadrant exterior to the illu- minator, is suspended on pivots GG (fig. 27) on either side of the Fic. 27. ee ee MLL LMLUTEULUUL LULU Fic. 28. illuminator, so that it can be swung to shut off light from the plane or lenticular edge. The rotation of the disk B allows either edge of the glass disk D to be presented to the source of illumination. A slit-diaphragm cut through a very thin brass disk is placed on the upper surface of B, and completes the device. No plan of mounting the semi-disk, or prism, or hemisphere, can, we think, be considered advantageous in which they are not left entirely free of the rectangular mechanical motions of the object- stage. As regards the use of a slit-diaphragm in connection with the swinging shutter, we possess a device, made seven years ago by Tolles, in which the slit is cut through the swinging shutter, which we think will be found the more convenient arrangement. Apams, J. M.—The Microscope among Infinities. [Speculations on the limits of perception. | The Microscope, 11. (1882) pp. 164-5. ns % How to turn over Small Objects. [‘‘ A simple and convenient way of turning over small objects, as corpuscles, epithelium, diatoms, &c., in a liquid, is to half fill a live-box and revolve the stage or hold the instrument so that it can be swayed out of level or from one side to another. In this way all sides can be easily and readily seen.” ] The Microscope, 11. (1882) p. 165. BLAcKBURN, W.—The Theory of Aperture in the Microscope: a popular exposi- tion. North. Microscopist, 11. (1882) pp. 325-34 (11 figs.). BuackHam, G.—Presidential Addresses at the Elmira Meeting of the American Society of Microscopists. [The Evolution of the Modern Microscope, &c. Cf. Vol. II. (1882) p. 698. Appendix of leading facts in the lives of R. B. Tolles, E, Gundlach, W. H. Bulloch, and the Bausch and Lomb Optical Co.] Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 4-5, 5-8, 25-47. 134 SUMMARY OF CURRENT RESEARCHES RELATING TO Borcker, E.—See Dippel, L., infra. Brapgpury, W.—The Achromatic Object-glass, XIII., XTV. Engl. Mech., XXXVI. (1882) pp. 351-2, 421-2. Bradford, Microscopical Society for. Micr. News, II. (1883) p. 24. Brirrain, T.—The Beginnings of Microscopic Study in Manchester [from 183 -82.] Field Natural., I. (14882) pp. 142-50. Carpenter, W. B.—On Angular Aperture in relation to Biological Investigation. [Title only of paper read in the Microscopical Section of the Amer. Assoc. Ady. Sci. Same as IT. (1882) p. 698.] Amer. Natural., X V1. (1882) p. 1050. = 5 Remarks made at the dinner of the New York Microscopical Society. [Personal recollections of the first development of the achromatic Microscope in London.] Amer. Mon. Micr. Journ., TI1. (1882) pp. 203-5, 219-20. Crisp, F.—Notes sur l’Ouverture, la vision microscopique et la valeur des objectifs a immersion & grand angle. (Notes on Aperture, Microscopical Vision, and the value of wide-angled Immersion Objectives. )—contd. (Transl. of paper, ante, I. (1881) pp. 303-60. } Journ. de Microgr., V1. (1882) pp. 473-5. CruMBAUGH, J. W.—The History of the Microscope and its Accessories, IV. The Microscope, II. (1882) p. 145-9. CuvitueR, AW—Ein Mikrometer-Kaliber. (Micrometer-Callipers.) [Allows of exact measurements to 0°01 mm. or 0°0004 in.] Centr.-Ztg. f. Opt. u. Mech., III. (1882) p. 260 (1 fig.), from Scientific American, 9th Sept. 1882. Davies, A. E.— Microscopical. [Commendation of Tolles’ Amplifier, and suggestion that instead of being serewed into the draw-tube it should be fitted in a box and made to slip in and out like the prism in the Wenham binocular. ] Engl. Mech., XXXVI. (1882) p. 276. Davis, G. E.— Dr. Carpenter in America. [Criticism of remarks on the aperture of objectives at the meeting of the Amer. Assoc. Ady. Sci. at Montreal. Vol. IL. (1882) pp. 698 & 854. ] Micr. News, III. (1882) pp. 15-18. , Preparing drawings for the Microscopical News. [Deals with the value of Photo-zincography for illustrating microscopical literature, with directions for drawing. ] Micr. News, II. (1882) pp. 19-21 (1 fig.). Dayton, R.—Modification of the Wenham Half-disk Illuminator with an improved Mounting. ([Supra, p. 132.] Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 161-3 (8 figs.). Derckr, T.—Brief Description of Large Microscope and Apparatus for Photo- graphing large Sections. [Post.] Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 277-9. Disp, W. J.—Hot Stage. (Supra, p. 131.) Journ. Post. Micr. Soc., I. (1882) pp. 177-8 (1 fig.). Drpret, L.—Das Mikroskop und seine Anwendung. (The Microscope and its use.) 2nded. Part 1. Handbuch der Allgemeinen Mikroskopie. (Hand- book of General Microscopy.) Sec. 2, pp. 337-736 (figs. 190-506). 8vo, Braunschweig, 1882. » » . Hin neuer beweglicher Objecttisch. (A new movable stage.) [Devised by E. Boecker of Wetzlar. Does not appear to be specially novel.) Bot. Centralbl., XII. (1882) pp. 385-6. Feit, G. E—The Microscope and Medicine. {Remarks on the value of the Microscope in medical research. ] The Microscope, II. (1882) pp. 149-56, ” Fieminc, J.—Microscopical Studies. [Lecture to Mutual Improvement Society. St, Matthias’ (Salford) Parish Magazine, VIII. (1882) pp. 10-11. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 135 Frasse & Co.’s Mikrometer-Dickmesser. (Micrometrical-measurer of thickness). [Measures to 1-1000th in.] Centr.-Ztg. f. Opt. u. Mech., III. (1882) p. 274 (1 fig.). Gintay, E.—Ueber die Abbe’sche Camera Lucida und eine im allgemeinen an Cameras anzubringende Verbesserung. (On the Abbe Camera Lucida and an improvement applicable to Cameras in general.) [Post.] Bot. Centralbl., XII. (1882) pp. 419-22. Grirrita, E. H.—The improved Griffith Club Microscope. [Supra, p. 113.] Proc. Amer. Soc. Micr., 5th Ann. Meeting, pp. 149-52 (3 figs.). Cincinn. Med. News, XI. (1882) pp. 762-4 (2 figs.). Grunow’s (J.) New Camera Lucida. [Supra, p. 120.] Amer. Mon. Micr. Journ., III. (1882) p. 201 (1 fig.). Gunypiacu, E.—On Light and Illumination. Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 79-90, 255-61. Hasert, B.—Kombination von Okularlinsen welche die Achromatisirung eines einfachen Kronglas-Objektives direkt bewirken. (Combination of ocular- _ lenses which effect the achromatising of a single crown-glass objective.) [Title (only) of German Patent No. 20729, 4th April, 1882.] Centr.-Ztg. f. Opt. u. Mech., 111. (1882) p. 288. Hitcenporr, F.— Apparat fiir mikroskopische geometrische Zeichnungen. (Apparatus for microscopical geometrical drawings.) [ Post. ] Zeitschr. f. Instrumentenk., IL. (1882) pp. 459-60 (1 fig.). Hircucock, R.—Remarks on the Illumination of Insect Preparations mounted without pressure. [ Post.] Amer. Mon. Mier. Journ., Til. (1882) p. 219. 5 ; The Podura-scale. [Remarks on the different appearances with objectives of different makers. ] Amer. Mon. Micr. Journ., I11. (1882) pp. 224-5. x » Commendation of Spencer’s 1-15th in. ‘‘ Professional” objec- tives. Also of Tolles’ 1-6th in. on Amphipleura pellucida. Amer. Mon. Mier. Journ., 111. (1882) p. 238. 5 » Note on the aperture discussion at Manchester. Amer. Mon. Wier. Journ., IIL. (1882) p. 238. Hitcheock’s (R.) Journal. [Anonymous criticism of note on p. 177 of Vol. III.] The Microscope, 11. (1882) p. 166. Hoveuton, W.—The Microscope and some of the wonders it reveals. 4th ed. iy. and 128 pp. (47 figs.). 8vo, London, n. d. “ Jumbo” and “‘ Midget” Microscopes. [‘‘ Among the curiosities recently exhibited by a London Society was the Microscope of half a century ago, weighing 125 pounds, and the.‘ Midget,’ a modern invention, weighing only a few ounces,’ so says a newspaper.’ The Microscope, 11. (1882) p. 172. Kent, W. K.—Live Cage for dry objects. [“‘ It consists of a wooden slide, with a cover-glass set near one end, and a spring-clamp near the middle. In other half slides of different thickness cover-glasses were inserted (sic), and these, when placed under the spring- clamp, which held them firmly in place, made conyenient cells.’’| The Microscope, II. (1882) p. 172. Krvzss, H.—Die wissenschaftlichen Instrumente auf der Bayrischen Landes- Industrie-, Gewerbe-, und Kunst-Ausstellung in Niirnberg 1882. (The Scientific Instruments at the Bavarian Rural-Industrial, Trade, and Art Exhibition in Niirnberg 1882.) [Brief reference to a Microscope made by the Niirnberg Industrial School.] Centr.-Ztg. f. Opt. u. Mech., IIl. (1882) pp. 255-9. M°Catzta, A.—Circular (from the President) to the Members of the American Society of Microscopists. [Exhortation to co-operation with the officers of the Society to advance the cause of microscopical research and scientific progress. ] 14th October, 1882. 136 SUMMARY OF CURRENT RESEARCHES RELATING TO Menpenuatt, T. C.—On the Fasoldt Stage Micrometer. [Records results of measurements—500 or 600.] Proc, Amer, Soc. Micr., 5th Ann. Meeting, 1882, pp. 201-8 (2 pls.). Mercer, A. C.—Stereoscopic effects obtained by the high-power binocular arrange- ment of Powell and Lealand. [ Vol. II. (1882) p. 271.] Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 127-30. ‘ Microscopical News, and Northern Microscopist ’—Note “ to our readers” [on the change in title and as to future arrangements. ] Micr. News, IIL. (1883) pp. 1-2. Moors, A. Y.—Camera Lucida. [Vol. II. (1882) p. 865.] Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, p. 283. Nosert, F. A.—Die héchste Leistung des heutigen Mikroskops und seine Priifung durch kiinstliche und natiirliche Objecte. (The best performance of the present Microscopes and their testing by artificial and natural objects.) [Post.] M. T. Naturwiss. Ver. Neu-Vorpommern, XIII. (1882) pp. 92-105. Peasr’s (J. L.) new Method of Attaching Objectives. [A Nose-piece—* its operation resembles that of the self-centering chucks used by mechanics ; the objective is held firmly as in a vice, and its center- ing is perfect. Changing objectives is accomplished with great rapidity and ease.” |} Amer, Mon. Micr. Journ., III. (1882) pp. 237. PeLLETAN, J.—Criticism of Dr. Carpenter’s remarks on objectives of small and large aperture at the Montreal meeting of the Amer. Assoc, Ady. Sci. [Supra, p. 120.]} Journ. de Microgr., VI. (1882) pp. 543-4. Putin, J.—How to use the Microscope. 5thed. 264 pp. 12mo, New York, 1882. - Postal Microscopical Society.—Rules and Names and Addresses of Members. Supplt. to Vol. I. of Journ. Post. Micr. Soc. (1882) 17 pp. “ Prismatique.”—Object-glass working, IIT. Engl. Mech., XXXVI. (1883) p. 397. Pritchard, Andrew, Death of. Sci.-Gossip, 1883, p. 16. Projection-Microscopes. [Note @ propos of Dr. H. Schréder’s article II. (1882) p. 673. “ The perfecting of such Microscopes would be a desideratum.”] Journ. of Sci., TV. (1882) p. 753. Rosinson, W., junr.—Micro-photography. [Reply to “ Density,” II. (1882) p. 863.—* The distance between the visual and actinic foci is the same no matter how much the conjugate focus may vary.’’] Engl. Mech., XXXVI, (1882) p. 324. Rogers, W. A.—A study of the problem of fine rulings with reference to the limit of naked-eye visibility and microscopic resolution. pute oe) of paper read in the Microscopical Section of the Amer, Assoc. Ady. Sci. Amer. ee XVI. (1882) p. 1050. (Cf. Brief note, also pp. 1042-3.) a4 rr On the conditions of success in the construction and the com- parison of standards of length. Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 231-51 (1 fig.). §., W. J.—[Note on the desirability of a universal gauge for eye-pieces and substage fittings. ] Sci.-Gossip, 1882, p. 276. Scuroeper, H.—[Note recording the discovery of optical glass, by the use of which the secondary spectrum is removed, leaving only “an extremely small tertiary spectrum which under ordinary conditions is scarcely visible.” Centr.-Ztg. f. Opt. u. Mech., III. (1882) p. 261. Scorr, E. T.—Microscope Noses and Screws. [“‘ Don’t believe that one screw that is turned to fit one body, and is properly adjusted, will really be so for another body.” | Engl, Mech., XXXVI. (1882) p. 362. Scovill Manufacturing Co.’s apparatus for photographing microscopical objects, Note on, Amer. Mon. Micr. Journ., IIL. (1882) pp. 218-9. eames ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 137 SurrH, H. L.—Memoir of C. H. Spencer. Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 49-74 (Portrait). Spencer, C. A., Memoir of. See Smith, H. L. Srearn’s (C. H.) Incandescent Electric Light applied to microscopical illumina- tion. [ Supra, p. 29.] Engl. Mech., XXXVI. (1883) p. 403. SrowELL, C. H. and L. R.—Criticism of the prices asked for some second-hand apparatus. The Microscope, Il. (1882) p. 176. Stowell’s (C. H. and L. R.) election as honorary members of the Aurora Micro- scopical Club. The Microscope, II. (1882) p. 166. SurroLK, W. T.—Standard sizes for eye-pieces. [Calling attention to the recommendations of the Committee, II. (1882) p. 595. ] Sci.-Gossip, 1883, p. 17. SunpELL, A. F'.—Aenderungen in der Brennweite eines achromatischen Objectivs durch Temperatur-variationen. (Changes in the focal length of an achromatic objective through variations of temperature.) [Experiments on Telescopic Objectives. Description of Apparatus. Differ- ences of 28°1° C. and 31°9° C. produced changes of 1:72 mm. and 2°05 mm. } Zeitschr. f. Instrumentenk., IIL. (1882) pp. 410-1, from Astronom. Nachr., No. 2450. Taytor, G. C_—An Improved Lamp for use with the Microscope. [Vol. II. (1882) p. 866.] : Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 14 and 273. THOULET, —.—Heating Apparatus for the Microscope. [Post.] Amer. Natural., XVII. (1883) p. 76, from Bull. Soc. Mineral. France. Torrie, Prof. A. H.’s, Address delivered before the new Section of Histology and Microscopy of the Amer. Assoc. Ady. Sci. at Montreal. {In justification of the formation of the Section.] Amer, Mon. Micr. Journ., III. (1882) pp. 205-10, 218. Watmstey, W. H.—Micro-photography with dry-plates and lamp-light and its application to making lantern positives. [ Post. ] Proc. Amer. Soc. Mier., 5th Ann. Meeting, 1882, pp. 179-82, 273-5. Warp, RK. H.—Report of Committee on Eye-pieces. [Vol. II. (1882) p. 853.] Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, p. 16. a », Report of National Committee on Micrometry. [A ruling upon a platino-iridium bar has been tested by the Coast Survey, and will soon be in the hands of the Committee. ] Proc. Amer, Soc. Micr., 5th Ann. Meeting, 1882, p. 16. Warson’s Lithological Microscope. [ Described, Vol. II. (1879) p. 470.] Amer. Mon. Micr. Journ., III. (1882) pp. 226-7 (1 fig.). B. Collecting, Mounting and Examining Objects, &c. Carbonic Acid as a Narcotic for Marine Animals.*—Dr. H. Fol recommends carbonic acid as the best narcotic for marine animals go as to preserve their form and habit. The ordinary narcotics, if in small doses, do not render the animals immovable, whilst in large they act as poisons. The same applies to the solutions of ether, chloroform, &c. ; If the sea-water in which a Medusa is swimming is saturated with carbonic acid the animal soon becomes completely immovable and insensible, retaining at the same time its natural appearance. If it is left in an hermetically closed vessel it will remain hours and even days unchanged, but immediately becomes lively again when it is placed in pure sea-water. Starfishes remained immovable four days, and * Zool. Anzeig., v. (1882) pp.. 698-9. Bull. Soc. Belg. Micr., ix. (1882) pp. 35-36. 138 SUMMARY OF CURRENT RESEARCHES RELATING TO after half an hour in fresh sea-water were as active and healthy as if nothing had happened. The experiment fails, however, for fishes and Mollusca, and Crustacea only endure it for a short time. In addition to the value of this method for photography, it will prove useful for distributing living marine animals and for physio- logical purposes. Corallin as a Microscopical Reagent.*—I. Szyszylowicz distin- guishes the various descriptions of mucilage occurring in the vegetable kingdom as follows:—1. Mucilage, i.e. substances which swell in water, are nearly allied chemically to cellulose, are coloured blue by iodine and sulphuric acid or zine chloride, and which yield oxalic acid . when boiled with nitric acid; examples, salep, Symphytum, &e. 2. Gums, which also swell in water, dissolving at the same time, are not coloured blue by iodine even on addition of sulphuric acid and zine chloride, and which yield mucic acid when boiled with nitric acid ; examples, Tilia, Osmunda, &c. 3. Mixtures of mucilage and gum, which the author calls gum-mucilage; and which combine the properties of the two first kinds; these are the most common in the vegetable kingdom; examples, Linum, Plantago, Althea, &e. At present we have no microscopical reagent for gum, mucilage, or gum- mucilage, except the property of swelling, and the stronger refringence than the surrounding substances; but these are not always sufficient. Corallin (sometimes called rosolic acid) is obtained by the action of sulphuric acid on phenol in the presence of oxalic acid, and is strictly a pigment composed of aurin and rosolic acid. The author employs it only dissolved in sodium carbonate, when it is of a purple- red colour not changed by exposure to light. The reagent acts differ- ently on the mucilage derived from starch, as in the tubers of Orchidee, and on that derived from cellulose, as in the root of Symphytum. The colour imparted to starch-mucilage by corallin is remarkably durable ; even long-continued boiling in alcohol does not cause any change, which is the more characteristic from the cell-walls and the protoplasm remaining perfectly clear. Cellulose-mucilage is also coloured by corallin, but the colour is destroyed by cold, and still more by hot aleohol. The pigment has no effect whatever on gum. Gum- mucilage is more or less coloured, the shade and permanence of the colour depending on the proportion of the two ingredients. The re- agent enables one to detect the smallest quantity of mucilage, and its power of swelling, which has not been the case before. It is of especial value in the examination of the callus in sieve-tubes. In similar cases Russow uses anilin-blue to distinguish the callus-plate ; but the author maintains that corallin produces a better result when the callus is beginning to swell or is already dissolved. The preservation of preparations coloured by corallin is not always possible. The author has preserved very beautiful prepara- tions from starch-mucilage in Canada balsam, but others, and espe- cially those with gum-mucilage, have not been so successful, the * Osobne odbicie z Rozpran Akad. Umiej w Krakowie, x. (1882). See Bot. Centralbl., xii. (1882) p. 138. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 139 colour being attacked, as might be expected, by the preserving material. Preparing Bacillus tuberculosis.*—Prof. J. Brun proposes the following “‘ameliorations ” to Koch and Ehrlich’s processes. Ist. Not to coagulate the albumen by heat, avoiding desiccation at more than 80° C. At 100° or 120° C. the bacteria are contracted. 2nd. To render the organic matter transparent by acetic acid :— Concentrated nitric acid 5 parts, glacial acetic acid 10 parts, water 55 parts. 3rd. To neutralize the nitric acid which, remaining to a greater or less extent in the organic layer, at length decolorizes the bacteria and renders them invisible. For this purpose is to be used a con- centrated aqueous solution of aniline which neutralizes all the acid not removed by repeated washings. 4th. To avoid Canada balsam, the index of which (1-538) is too high, and to take a neutral liquid having the same index as the albuminoid substances (1°37):—Very white gelatine 14 parts, salicylic acid :25, distilled water 88. This has an index of 1-356 for the yellow rays. Castor-oil can also be used, though its index is 1:46. It is better to leave the field uncoloured than to colour it an orange-brown with vesuvine or other colouring matter, because the blue of the bacteria is rendered fainter by the complementary orange tint. Staining Bacteria.s—Professor C. Weigert adopts two distinct principles in the staining of bacteria for microscopical examination, according as they occur on the one hand in clear liquids or dried masses, or, on the other, in tissues of which, after hardening, sections can be made. For most Micrococci all nucleus-staining substances are suitable, viz. (red) all the modifications of carmine, also purpurin, fuchsin, and Magdala-red ; (brown) Bismarck-brown, vesuvin ; (violet- brown) carmine, the preparations being washed, after staining, in alcohol, to which some chloride of iron has been added; (green) methyl-green; (blue and violet) hematoxylin, iodine-violet, methyl- violet, dahlia, gentian-violet. For staining Bacilli and the rare Megacocci, anilin colours are alone recommended; carmine and hematoxylin produce no effect; of the anilin colours only those which stain nuclei, viz. the basic compounds (e.g. Bismarck-brown, methyl-violet, methyl-green, saf- franin, fuchsin, magdala, &c.) are applicable; gentian-violet appears to be especially suitable ; the objection to methyl-violet and fuchsin is that in decolorizing in order to leave only the nucleus stained, the * Bull. Soc. Belge Micr., viii. (1882) pp. clxixIxxvii. Journ. de Microgr., vi. (1882) pp. 500-3. + In Bull. Soc. Belge Micr. this is given as 15 parts. : { In Journ. de Micr. this formula is not given, but in place of it the follow- ing, which in Bull. Soc. Belge Micr. is said not to preserve so well the colour of the bacteria :—Glycerine 10, commercial glucose 40, camphorated alcohol 10, water 140. The index is 1°37. _ § Arch. pathol. Anat. (Virchow), Ixxxiv. (1881) pp. 275-94. 140 SUMMARY OF CURRENT RESEARCHES RELATING TO colour is apt to go altogether. Some of these colours are unsuited to certain bacteria, e.g. Bismarck-brown does not stain the bacillus of lepra at all, and that of splenic fever but badly. In order.to stain the bacteria, the sections are placed in a 1 per cent. watery solution of the dye; ina few moments they are deeply coloured, and may then be “ differentiated ” (the term applied by Professor Weigert to the process of removal of the colour from the body of the cell), by means of alcohol, in which they may be allowed to lie more than an hour; if oil of cloves is used, they may be left in it half an hour and upwards; then if there is not time to examine them, they may be put into water for as much as a day without losing their colour. The use of absolute alcohol for the washing is specially recommended ; for gentian-violet, which strongly resists the washing-out process, treatment with oil of cloves, and then with alcohol, transferring back to the oil, is the quickest way. Gentian-violet is particularly useful when it is uncer- tain what form of bacterium is present, but the colour is removed from the nuclei when placed in glycerine. Double-staining is very useful for colouring the nuclei and the bacteria differently; of all combinations picrocarmine was found to be the best ; it is used as made in the following way, in preference to commercial specimens of this reagent, which Professor Weigert finds are seldom entirely satisfactory :— Over 2 grammes of carmine are poured 4 grammes common ammonia, and the whole left 24 hours in a place protected against evaporation ; 200 grammes of a concentrated picric acid solution are then poured in; the mixture is left 24 hours until all soluble matters are dissolved. Very small quantities of acetic acid are then added until a slight precipitate comes down even after stirring; a rather copious precipitate is usually thrown down in the course of the next 24 hours ; it should be removed by filtration. A picrocarmine which does not stain readily may be improved by addition of acetic acid. After staining, the sections should be washed in pure water or water containing only a trace of acid. In applying double-staining to bacteria contained in the tissues, the sections should first be treated with gentian violet and alcohol, placed for a moment in water to remove the alcohol and then placed in the picrocarmine and kept there for half an hour or an hour; the- superfluous picrocarmine is washed away with water, and the specimen well washed with alcohol and mounted in Canada balsam, after passing through oil of cloves. This method may be applied to Micrococei, care being taken not to stain them red by a too protracted sojourn in the picrocarmine. Actinomyces is not stained by the usual nucleus-staining prepara- tions ; orseille is used as prepared by Wed], and the sections left in it for about an hour; they are then washed superficially with alcohol and transferred to gentian-violet. The wall and contents of the cell of Molluscum contagiosum are differentiated by this method. Sections of tissues containing bacteria may be made by Roy’s microtome. The frozen sections are examined either fresh or in salt solution ; if they are to be stained and mounted they are spread out ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 141 with glass needles on a spatula, the superfluous salt solution is removed with blotting-paper, and the section is slowly immersed in absolute alcohol and left there until all air-bubbles have been removed. In all studies of bacteria by staining sections it is important to remember that the staining is apt to fail in the case of some of the micro-organisms, and thus give misleading negative results; the addition of some acetic acid or caustic potash before staining will generally remedy this defect, although the sections are somewhat impaired by these reagents. It is hardly necessary to record Professor Weigert’s warning that really good objectives are an absolute necessity for this work. Preparing Fatty Acids.*—Mr. F. J. Allen boils up the fat or oil with a not too strong solution of caustic soda or potash (liq. sodee or liq. potasse) until the alkali is quite saturated and refuses to absorb any more fat. When it has cooled filter it and add dilute’ sulphuric or hydrochloric acid (stirring and warming at the same time) until no more fatty acid separates. Boil for a second or two, then set aside to cool. When cold, the fatty acid will be found in a solid mass on the surface, and the liquid part may be thrown away. Tt is well to boil the acid in fresh water to purify it, when, on cooling, it will be practically pure. To get crystals, it is simply necessary to melt a small quantity on a slide, and spread it very thin ; it crystallizes on cooling, and must be mounted “ dry.” Carmine Solution.j—Prof. H. Hoyer, believing in the great superiority in all respects of carmine for animal tissues, strongly recommends the following as avoiding the objections which exist to the simple solution on account of the difficulty of keeping it, and other disadvantages. He is able to speak from a year’s trial. Dissolve 1 gr. of carmine in a mixture of 1-2 c.cm. of strong liquor ammoniz and 6-8 c.cm. of water, and heat it in a glass vessel in a sand bath until the excess of ammonia has evaporated. So long as free ammonia is present large bubbles are formed in the fluid, and the latter shows the usual dark purple-red colour of carminate of ammonia. When the free ammonia has evaporated small bubbles appear, and the solution takes a brighter red tint. It is now left to cool and settle, and by filtering, the bright red deposit (to be used over again) is separated from the neutral dark fluid, which by the addition of chloral-hydrate can be kept for a long time. If the carmine solution is mixed with 4-6 times its volume of strong alcohol a scarlet-red precipitate is formed. This is separated by filtration, washed and dried, or made into a paste with alcohol in which some glycerine and chloral is dissolved. Both the powder and the paste can be kept several months unchanged ; they dissolve easily in distilled water, particularly the paste. The solution passes readily through the filter, whilst the ordinary carmine solution can * Journ. Post. Mier. Soc., i. (1882) p. 193. + Biol. Centralbl., ii. 1882) pp. 17-19. t Cf. infra, p. 142, as to its use in the preparation of a red injection-mass 142 SUMMARY OF CURRENT RESEARCHES RELATING TO only be filtered with difficulty ; it also keeps a long time unchanged, especially with the addition of 1-2 per cent. of chloral, and it has a much more intense colouring power. By dissolving the carmine powder in a concentrated solution of neutral picrate of ammonia a combination is obtained which unites all the advantages of ordinary “picrocarmine” without any of its disadvantages. Prussian Blue and Safranine for Plant Sections.*—Prof. J. Brun refers to the process of double staining for vegetable histology described by him to the Geneva Physical and Natural History Society, in which the action of Prussian blue alternates with that of safranine. The process is to be recommended for the clearness with which the preparations show all the minutest details, even in the interior of the cells. The chlorophyll retains its colour, while the cellulose, the layers of the cell-walls and their contents, the incrusting matter, and the fatty or resinous substances are, on the contrary, differently coloured and readily differentiated. He insists on the value of these histo-chemical processes in distinguishing very minute transparent bodies, and above all to differentiate organs scattered through opaline liquids or colourless histological elements. Injection-Masses.t—Prof. H. Hoyer describes several compounds which he has found useful for this purpose, the essential point being the use of gelatine, the great objection to which is remedied by adding to it chloral hydrate, which protects it from deteriorating by fungoid growths. It is thus possible to have a stock of different coloured masses eminently suited for injection purposes, and which only require to be warmed before immediate use. _ For a transparent red mass take a concentrated gelatine solution, and add to it a corresponding quantity of the carmine solution described supra p. 141. Digest in a water bath until the dark violet-red colour begins to pass into a bright red tint. Then add 5-10 per cent. by volumes of glycerine and at least 2 per cent. by weight of chloral in a concentrated solution. After passing through flannel it can be kept in an open vessel under a bell glass. A blue mass can be made by mixing a small quantity of a very dilute and warm solution of Berlin blue with an equally small quantity of a moderately dilute gelatine-solution, by which a clear homogeneous blue solution is obtained. This is again mixed with larger quantities of concentrated warm gelatine-solution, with the gradual addition of now only a moderately dilute solution of Berlin blue. A homogeneous transparent saturated mass is thus produced. The addition of chloral and glycerine enables it to be kept for a long time. For a fluid yellow in the capillaries and brown in the larger vessels the following is given. A concentrated solution of gelatine is mixed with an equal volume of a 4 per cent. solution of nitrate of * Bull. Soc. Belge Micr., viii. (1882) pp. clxix.-lxx. Journ, de Microgr., vi. (1882) p. 500. + Biol. Centralbl., ii. (1882) pp. 19-22. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 143 silver, and warmed. To this is added a very small quantity of an aqueous solution of pyrogallic acid, which reduces the silver in a few seconds; chloral and glycerine are added as before. It does not change either in alcohol, chromic or acetic acid, or in bichromate of potash, &c., so that the objects can be hardened in different fluids. Blue and yellow masses mixed give a very useful green. Prof. Hoyer recalls attention to two other formule previously described by him,* but “which have not received any notice in histo- logical text-books.” The one is ammonio-nitrate of silver, especially suitable for the endothelium of vessels and fine vessels generally, and much to be preferred to the simple nitrate of silver solution. The other is spirituous solution of shellac. Taylor’s Freezing Microtome.j—This microtome (fig. 29), the invention of Dr. T. Taylor, Microscopist of the Agricultural Depart- ment at Washington, is claimed to present “all the advantages of any plan heretofore employed in hardening animal or vegetable tissues for section cutting, while it has many advantages over all other devices employed for the same purpose. Microscopists who are interested in the study of histology and pathology have long felt the necessity for a better method of freezing animal and vegetable tissue than has been heretofore at their command. In hardening tissues by chemical agents the tissues are more or less distorted by the solutions used, and the process is very slow. ther and rhigolene have been employed with some degree of success, but both are expensive and they cannot be used in the presence of artificial light because of danger of explosion. Another disadvantage is that two persons are required to attend to the manipulations, one to force the vapour into the freezing box while the other uses the section-cutting knife. The moment the pumping of the ether or rhigolene ceases, the tissue operated on ceases to be frozen, so ephemeral is the degree of cold obtained by these means, * Arch. f. Mikr. Anat., xiii. (1877). + Amer. Mon. Micr. Journ., iii, (1882) pp. 168-9 (1 fig.). 144 SUMMARY OF CURRENT RESEARCHES RELATING TO The principal advantages to be obtained by the use of the Taylor Microtome are, lst, great economy in the method of freezing, and 2nd, celerity and certainty of freezing. With an expenditure of twenty-five cents the tissues to be operated on can be kept frozen for several hours at a time. Small objects immersed in gum solu- tions are frozen and in condition for cutting in less than one minute.” A is a revolving plate by which the thickness of the section is regulated, and in the centre of which is an insulated chamber for freezing the tissue. A brass tube enters it on each side. The larger one is the supply tube, communicating with a pail on a bracket above the microtome, whilst to the smaller one is attached a rubber tube, which discharges the cold salt water into a pail placed under it. The salt and water liquid, as it passes from the upper to the lower pail, is at a temperature of about zero. The water should not be allowed to waste, but should be returned to the first pail for continual use, or as long as it has freezing properties. As a matter of further economy it is necessary to limit the rate of exit of the freezing water. This is regulated by nipping the discharge tube with the spring clothes- pin supplied for the purpose. Should the cold within the chamber be too intense the edge of the knife is liable to be turned and the cutting will be imperfect. When this occurs the flow of water through the chamber is stopped by using a spring clothes-pin as a clip on the upper tube. In order to regulate the thickness of the tissue to be cut a scale is engraved on the edge of the revolving plate A, which, in conjunction with the pointer e, indicates the thickness of the section. Mr. C. P. Lyman, of the Department of Agriculture, writing in strong commendation of the apparatus, says :—“ There is no little box that must be kept full of ice and salt and constantly attended to ; neither is there any tiresome bulb to squeeze for a period of any- where from fifteen minutes to two hours, nor the expense and danger attending the general use of ether or rhigolene. The simplicity of the operation of freezing morbid material for sections, now obtainable through the use of this instrument, will, I think, remove from the study of pathology one of its hitherto greatest bugbears, viz. the great labour of preparation of material for section and the difficulty of obtaining good sections of soft tissues unaltered by the various chemical reagents hitherto used for the purpose of hardening them.” Mounting Media.*—Prof. H. Hoyer has found excellent mount- ing media not only in L. Bach’s solution of gum arabic in liquor ammonie aceti, but also in acetate of potash, as well as a third modi- fication with glycerine and chloral. The two former are more particularly suitable for preparations stained with aniline colours, especially bacteria. The latter is suitable for sections hardened in chromic acid, alcohol, &¢., and objects coloured with carmine or hematoxylin. * Biol. Centralbl., ii. (1882) pp. 23-4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 145 The solutions are thus prepared :—A high 60 ¢.cm. glass with a wide neck is filled two-thirds full with selected white gum arabic (in pieces, not powder), and then acetate of potash or ammonia is added, or a solution of chloral-hydrate (of several per cent.) to which 5-10 per cent. of glycerine has been added. The gum with frequent shaking dissolves in a few days and forms a syrupy fluid, which is slowly filtered for twenty-four hours. The clear filtered fluid will keep a long time, but if spores of fungi begin to develop a little chloral can be added and the fluid refiltered. Preparation of Dammar Varnish.*—C. J. M. says that none of the receipts given in books enable the amateur to prepare a satisfactory article. Dammar is not entirely soluble in ether, benzole, or turpen- tine, at ordinary temperatures. If heat be used, the solution is more complete, but, sooner or later, the product will become milky, and then it will be found impossible to clarify it. ‘ To obtain a perfectly limpid solution, permanently remaining so, proceed as follows: To 4 drachms of crushed Indian dammar add 8 liquid drachms ‘of pure benzole, and allow the resin to dissolve at the ordinary temperature. After a day or two, an insoluble residue will be found at the bottom of the vessel. Carefully decant the supernatant clear liquid, and add to it 80 minims (14 drachm) of spirits of turpentine. The preparation is thencomplete. The object of adding turpentine is to ensure toughness in the dried film. Without the turpentine the dried film would be brittle. He does not think that any advantage is derived from the addition of mastic to the preparation. Hunt’s American Cement.;—Mr. J. Ford has received from an American correspondent the following recipe for making the cement, so effectually used by professional mounters, and which has been regarded as a trade secret :— “Take some zinc white as sold for painters’ use, drain off the oil, and mix with Canada balsam, dissolved very thin with chloroform. If it does not flow freely from the brush, add a little turpentine. The mixture should be about the thickness of cream, and kept in a bottle with a glass cap.” Mr. F. J. Allen adds :—Having sealed the slide with the cement, paint on it with artists’ oil-colours, thinned if necessary with turpen- a and when dry varnish it with very dilute balsam to give it a gloss. Mayer’s Water Bath.t—A convenient form of water bath, devised by Dr. P. Mayer, is shown in fig. 30. It is a small brass box, 18 cm. long, 9 cm. wide, and 8 em. high. The tube A, through which the water is received, and the rod B serve as handles. The receiving tube is closed by a cork provided with a glass tube for the escape of steam, which is bent in the form of * Sci.-Gossip, 1882, p. 257. + Journ. Post. Micr. Soc., i. (1882) p. 193. t Cf. C. O. Whitman in Amer, Natural., xvi. (1882) p. 785 (1 fig.). Ser. 2.—Vot. III. L 146 SUMMARY OF CURRENT RESEARCHES RELATING TO a siphon to protect against dust. At 1-5 cm. from the base of the box is an oven (D) *7 cm. high, and 12 cm. long, which passes completely through the box, and serves for warming the slides when shellac is used. Above are two circular basin-like pits (P)5°5 em. in diameter, and 4 cm. deep, for receiving the Fic. 30. two tin paraffin holders. These are covered by circular plates of glass. There are also six tubular pits, one for a thermometer (T), the other for glass tubes. This water bath will be found useful for other purposes than those of imbedding and mounting. It will of course be understood that the only object of giving its exact dimen- sions is to furnish a guide where one is required. There are at least two important & advantages offered by this water bath over those in general use, viz. the slides are pro- O +p tected from dust, and the paraffin is not ex- I posed to the water. ) | i i Packing Slides for Travelling. — Mr. L. tj i i Dreyfus describes the mode in which he “A i } transported from London to Wiesbaden his /) | collection of over 5000 preparations without | a single breakage :— “T used no wadding whatever, but packed the whole in racked boxes, and over the ends of the slides in the racks only, I put, with the handle of my scalpel, on each side a length of the smallest indiarubber tubing, such as is used for feeding-bottles. When the slides were so packed, two more lengths on the top, under the lid, before the latter was fastened down by two of the stouwtest indiarubber bands across the box in both directions (sides and bottom.) This allowed so much spring in every direction that no breakage occurred, although I have no doubt the heavy cases were handled in the usual delicate way by railway porters and sailors on board the steamer. Besides minimizing the risk of breakage, this style of packing has the advantage of being very easy and expeditious in packing and unpacking, and perfectly clean. The preparations come out as clean as they were packed, and can be packed into the cabinets without the tedious wiping required after the use of cotton wool. Tubes and rings can be used over and over again, so that the extra expense is very small.” Examination of Living Germs in Water.*—At a recent meeting of the Manchester Literary and Philosophical Society, Dr. R. Angus Smith stated that Dr. Koch, of Berlin, advocated the use of gelatine ~ in preserving indications of organic vitality. About 2} per cent. of gelatine, well heated in a little water, is mixed with the water to be tested, and the mixture forms a transparent mass, in which * Chem. News, xlvi. (1882) pp. 288-90. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 147 soluble or unobserved matter, developed from the organic matter of the waters and made visible in a solid and insoluble form, does not fall to the bottom, but shows round each active point the sphere of its activity. The gelatine keeps a record, for a time, both of the quality and intensity of life in the liquid, every little centre of life making itself apparent to the eye. It seems, therefore, to Dr. Smith essential that all chemical examinations of water should be supplemented by an inquiry, like this of Dr. Koch’s, into the comparative activity of the living organisms. In some waters a centre makes around it a sphere, which has the appearance of a thin vesicle, and is filled with liquid. These spheres form in a day or two, according to the water, and at their bottom is a white mass, containing chiefly active bacteria. The liquid filling the spheres may be taken out by a pipette and examined, with the bacteria which lie at the bottom. Dr. Smith has not yet examined a sufficient number of waters to give general rules, but hopes to do so. He has as yet examined no chalk water for example, but has been confined chiefly to the Manchester district hill water, impure brook and pond water, Mersey, Irwell, and Medlock water, and canal water. In certain specimens of Manchester water the spheres appear on some days to be few in number, on other days the amount is enormous, the whole of the tube in which the experiment is made being filled with them. At such times the water is highly impure, and complained of by the public. Dr. Smith says that when the tests are sufficiently developed, ‘‘ chemists must prepare for a new condition of things.” Sinel’s Embryological Slides.—Sinel & Co. of St. Helier’s, Jersey, have issued a series of these slides, in the notice of which they refer to the difficulty of preserving delicate embryological objects for microscopical examination. “The favourite medium of the microscopist has hitherto been Canada balsam, and owing to the non-existence of a cement sufficiently powerful to hold fluid in a cell, this latter medium has been viewed with some suspicion. It -would, however, be useless to attempt the preservation of the ova of Crustacea or Mollusca in Canada balsam, but the medium used for -these slides, being of the same density as sea-water (and also of such an admirable preservative character that the living appearance of the objects is fully retained) is the most successful yet met with. “The slides are constructed with a cement of such power and hardness that they have stood a test that would even damage a balsam mount, viz. a temperature ranging from 28° to 120° F., without the slightest effect upon the slide or object, and of the numbers that have been prepared in this manner none have been found to leak, as is frequently the case with ordinary fluid mounts. No slides are sent | out till they have been left some considerable time to test and harden.” The list includes the ova, in various stages of development, and the young of Fishes, Mollusca, Insecta, Arachnida, Crustacea, and Echinodermata, with a series of six slides of the anatomy of Palemon varians. Eo yy 148 SUMMARY OF CURRENT RESEARCHES RELATING TO Search for ‘‘ Atlantis’ with the Microscope.* — Under this heading Dr. A. Geikie reviews a paper} by the Abbé Renard “ On the Petrology of St. Paul’s Rocks,” an island nearly on the equator, and about 500 miles east of the South American coast :— “« Are these rocks the last enduring remnant of ‘ Atlantis —a continent that has otherwise disappeared, or are they portions of a volcanic mass like the other islands of the same ocean? ‘To those who have not noted the modern progress of geological inquiry, it may seem incredible that any one should propose to solve this problem with the Microscope. To seek for a supposed lost continent with the help of a Microscope may seem to be as sane a proceeding as to attempt to revive an extinct Ichthyosaurus with a box of lucifer-matches. Yet in truth the answer to the question whether the St. Paul’s Rocks are portions of a once more extensive land depends upon the ascertained origin of the materials of these rocks, and this origin can only be pro- perly inferred from the detailed structure of the materials, as revealed by the Microscope. The importance of microscopical examination in geological research, so urgently pressed upon the notice of geologists for some years past, has sometimes been spoken of disparagingly, as if the conclusions to which it led were uncertain, and hardly worth the labour of arriving at them. We occasionally hear taunts levelled at the ‘ waistcoat-pocket geologists, who carry home little chips of rock, slice them, look at them with their Microscopes, and straightway reveal to their admiring friends the true structure and history of a whole mountain-range or region. That the sarcasm is often well- deserved must be frankly conceded. Some observers with the Micro- scope have been so captivated with their new toy as to persuade themselves that with its aid they may dispense with the old-fashioned methods of observation in the field. But there could not be a more fatal mistake. The fundamental questions of geological structure must be determined on the ground. The Microscope becomes an in- valuable help in widening and correcting the insight so obtained ; but its verdict is sometimes as ambiguous as that of any oracle. In any case it must remain the servant, not the master, of the field- geologist.” M. Renard has undertaken a most elaborate investigation (chemi- cally and microscopically) of sections of the rocks brought home by the ‘Challenger, with the view of determining whether they were to be considered as volcanic or to be classed among the crystalline schists. If they belong to the latter, they must once have lain deeply buried beneath overlying masses, by the removal of which they have been revealed. They would thus go far to prove the former existence of much higher and more extensive land in that region of the Atlantic ; - land, too, not formed of mere volcanic protrusions, but built up of solid rock-masses, such as compose the framework of the continents. Tf, on the other hand, the rock is volcanic, then the islets of St. Paul belong to the same order as the oceanic islands all over the globe. ‘The Abbé inclines on the whole to the side of the crystalline schists, * Nature, xxvii. (1882) pp. 25-6. + Ann. Soc. Belg. Micr., ix. (1882). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 149 but Prof. Geikie considers that the balance of proof is decidedly in favour of the volcanic origin of the rock. Cole’s Studies in Microscopical Science. — These have now reached the 40th number, and fully support the high praise which has been bestowed upon them in every direction, both for the informa- tion contained in the text, the beauty of the coloured illustrations, and the excellence of the accompanying slides. Mlicroscopists have long lamented that it was not possible to obtain a guide to the slides sold, so that the points of interest illustrated could be intelligently appreciated. Now that this is provided, it is to be hoped that they will bear in mind that something more is required than “ moral” support in order to ensure a continuation of the series. So many useful ventures have failed through microscopists trusting to their neighbours to provide substantial support, that it is necessary to urge that every one who believes in the value of Mr. Cole’s enterprise will himself subscribe to it. No more profitable return can, we are sure, be found for the small outlay required. ALLEN, F. J.—Dr. Hunt’s American Cement for Ringing Slides. [Supra, p. 145.] Journ. Post. Mier, Soc., 1. (1882) p. 193. Fatty Acids to prepare for the Microscope. [ Supra, p. 141.] Journ. Post. Mier. Soc., 1. (1882) p. 193. Buanc, H.—Encore une méthode pour conserver et colorer les Protozoaires. (Another method for preserving and colouring the Protozoa.) [Post.] Zool. Anzeig., VI. (1883) pp. 22-3. Boncuut, E.—Traité de Diagnostic et de Sémiologie comprenant l’exposé des procédés physiques et chimiques d’exploration médicale, auscultation, per- cussion, cérébroscopie, sphygmographie, laryngoscopie, microscopie, analyse chimique et l’étude des symptomes fournis par les troubles fonctionnels. [Chap. XIV. Emploi de la loupe et du Microscope. (Hmployment of the lens and the Microscope. ) pp. 155-76 (18 figs.). j 8vo, Paris, 1883, xi. and 692 pp. (160 figs.). Cuxrster, A. H.—Method of making Tin Rings ‘for Cells. [ Post. ] Proc. Amer. Soc: Micr., Sth Aun. Meeting, 1882, pp. 282-3. Couen, E., & J. Grimu.—Sammlung von Mikrophotographien zur Veranschau- lichung der Mikroskopischen Struktur von Mineralien und Gesteinen. (Collection of Microphotographs for the demonstration of the Microscopical Structure of Minerals and Rocks.) Part VII. 8 pls. 4to, Stuttgart, 1882. Cots, A. C.—Studies in Microscopical Science. No. 30 (pp. 209-216).—T. 8. Thallus of Lichen. Sticta aurata. Plate of 15 figs. No. 31 (pp. 217-220).—The Pancreas. T. 8. of Human Pancreas, injected carmine. Plate x 65. No. 32 (pp. 221-6).—Diabase. South Quarry, Corstorphine Hill, Edinburgh. Plate x 25. No. 33 (pp. 227-30).—The Spleen. T. 8S. of Human Spleen (of Infant), injected carmine and stained with hematoxylin. Diagrammatic Drawing. No. a (wr. 231-4).— Juncus communis var. effusus. T. S. of Stem. Plate xX 2 3 ” No. 35 ies 235-40).—The Spleen. T. 8. Spleen of Cat, stained logwood. Plate x 65. No. 36 (pp. 241-2).—Euphorbia splendens. L. 8. of Stem, stained logwood. Plate x 65 and 500. No. 37 (pp. 243-50).—The Salivary Glands. V.8. Submaxillary Gland of Dog, stained logwood. Plate x 500. No. 38 (pp. 251-6).—Section of Rock—Red Syenite. Ord Hill, Sutherland. Plate x 25. Description by Prof. M. F. Heddle. 150 SUMMARY OF CURRENT RESEARCHES RELATING TO Cornit & Ranvier.—Manual of Pathological Histology. Transl. by Hart. 2nd ed. Vol. I. 8vo, London, 1882. Cutting Sections of Dental Pulp. [** Harden in 1 per cent. aqueous solution of chromic acid, separated from the dentine ; or take fresh pulp from the extracted tooth, stain with car- mine, harden in glycerine to which add 1 per cent. acetic acid. In three to six months sections could be cut with a keen razor.” ] The Microscope, Il. (1882) p. 172, from New England Journal of Dentistry. DerckE, T.—Preparation and Mounting of Brain Sections. [ Post.] Proc, Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 275-80. Foi, H.—Ein Beitrag zur Technik fiir Zoologen am Meeresstrande. (A Contri- bution to Technics for Zoologists at the Sea-shore.) [Supra, p. 137.] . Zool. Anzeig., V. (1882) pp. 698-9. and in French in Bull. Soc. Belg. Micr., TX. (1882) pp. 35-7. Forp, J.—Dr. Hunt’s American Cement for Ringing Slides. [Supra, p. 145.] Journ, Post. Micr. Soc., I. (1882) p. 193. FreEMAN, H. E.—Grinding Sections of Teeth. {Employ ground-glass, using with it in the early stage fine-ground pumice- stone. } Journ, Post. Micr. Soc., I. (1882) p. 192. FrENzEL, J.—Beitrag zur Microscopischen Technik—Aufkleben der Schnitte. (Contribution to Microscopical Technics—Fixing the Sections.) [Post.] Zool, Anzeig., VI. (1883) pp. 51-2. FRIEDLAENDER, C.—Microscopische Technik zum gebrauch bei medicinischen und pathologisch-anatomischen Untersuchungen. (Microscopical Technics for use in medical and pathologico-anatomical investigations.) viii. and 132 pp., 8vo, Kassel and Berlin, n.d. Gacez, 8. H.—Observations on the Fat Cells and Connective-tissue Corpuscles of Necturus (Menobranchus). [Contains “ Methods of Investigation ” and making “ Permanent Microscopic Preparations.” ] Proc. Amer. Soc. Wicr., 5th Ann. Meeting, 1882, pp. 109-26 (1 pl.). GriesBacH, H.—Bemerkungen zur Injectionstechnik bei Wirbellosen. (Remarks on the Injection of Invertebrata.) [Post.] Arch, f. Mikr. Anat., XXI. (1882) pp. 824-7. Grimm, J. See Cohen, E. Hacer, H.—Arsennachweis auf mikroskopischem Wege. (Microscopical Analysis of Arsenic.) Chem. Centralbl., XIII. (1882) pp. 690-1, from Pharm, Centralh., X XIII. (1882) pp. 367-9. Havcr, F.—Die Meeresalgen Deutschlands und Oesterreichs. (The Marine Algz of Germany and Austria.) 8vo, Leipzig, 1883. [2nd vol. of Dr. L. Rabenhorst’s Cryptogamic Flora of Germany, Austria, and Switzerland. Ist part contains Introduction (pp. 1-6) on “ The Collection and Preparation of Marine Alge.”] Hircucocrk, R.—Examination and Exhibition of Living Organisms. [Place a drop of water containing the organisms on a cover-glass and invert over a ring of wax on a slide—melt the wax with a piece of wire to ‘make the cell air-tight. A small bit of Nitella, Anacharis, or some vigorously growing alga should be placed in the drop. In this way rotifers can be seen to develope and multiply for days. The plan is also recommended for showing cyclosis in a water plant. ] Amer. Mon. Micr, Jowrn., ILI. (1882) p, 222. es » The Mounting of Pollen Grains. [Dry—in wax cells (dusted in). Fluid—in castor-oil in shellac cells. Amer. Mon. Micr. Journ., III. (1882) p. 223. Horst, G. H.—The Microscopical Structure of Rocks. [Contains notes on the Microscope required and on preparing rock-sections.] Field Naturalist, I. (1883) pp. 169-71. Inepen, J. E.—Bleaching Leaves. [Note as to making chlorinated soda and mounting the leaves in glycerine jelly. anys Journ. Post. Micr, Soc., I. (1882) p. 191. RPE ag Ve aea.% ‘va ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 151 Kiuaasen, H. M.—To mount Plants in Glycerine and Water. [Add to the glycerine a few drops of carbolic acid to guard against fungoid growth—mix with equal parts water—don’t cement the cover- glass down, but let the water evaporate, and add more glycerine and water until the plant gets gradually filled with glycerine. Fasten the cover-glass by first ringing it with gelatine, to which any cement will adhere. | Journ. Post. Micr. Soc., 1. (1882) p. 192. Kossman, R.—Zur Microtomtechnik. (On Microtomes.) [Post.] Zool, Anzeig., VI. (1883) pp. 19-21. Lacamann, J. P.—See Poulsen, V. A. Lorrnovse, T. W.—Mounting the Proboscis of a Fly—Preparation. [ Post.] Micr, News, III. (1882) pp. 21-2 (1 fig.). MarcHat, H.—Des moyens matériels dans l’enseignement de la botanique. Le Microscope. 22 pp. (Materials for the teaching of Botany—The Micro- scope.) 8vo, Bruxelles, 1882. ~ » Hssai dune liste de préparations microscopiques destinées & Penseignement. 16 pp. (Attempt at a list of microscopical preparations intended for teaching.) 8vo, Bruxelles, 1882. Marlow’s (E.) Microscopical Compendium. [Cabinet for turntable, slides, brushes, bottles, &.] Sci.-Gossip, 1882, p. 277. Mikroskopische Praparate von Mikroorganismen, speciell v. pathogenen Bacterien. Collection I. (Unter Controle v. Fliigge in Gottingen angefertigt.) (Micro- scopical preparations of micro-organisms, especially of pathogenous Bacteria. Prepared under the direction of Fligge of Gottingen.) Cassel, 1882. Mosivus, K.—Kleine Mittheilungen aus der Zoologischen Technik. (Minor com- munications on Zoological Technics.) [Post.] Zool. Anzeig., VI. (1883) pp. 52-3. Moorz, A. J.—The preparation of Crystals. [The plan proposed has been found very unsatisfactory in England. ] The Microscope, 11. (1882) p. 164. Mouter, C. J.—On the discrimination of different species of wood by a micro- scopical examination of sections of branches. Sci.- Gossip, 1883, p. 9. Parsons, H. F.—Preventing. growth of Mildew on dry Mounts. [Paint the specimen and the interior of the cell with a solution of carbolic acid or corrosive sublimate in spirit before mounting. | Journ. Post. Micr. Soc., 1. (1882) p. 193. Paut’s (F. A.) Modification of Williams’ Freezing Microtome. [ Post.] Proc. Amer, Soc. Mier., 5th Ann. Meeting, 1882, pp. 283-4. Povutsen, V. A.—Microchimie végétale, guide pour les recherches phyto-histolo- giques a Vusage des étudiants.. (Vegetable Microchemistry, guide to phyto- histological researches for the use of students.) Translated by J. P. Lach- mann from the German edition. French edition, considerably enlarged (in collaboration with the author). xx. and 119 pp. S8vo, Paris, 1882. Reppine, T. B.—Osmic acid—its uses and advantages in microscopical investi- gations. [Post.]| Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 183-6. Rernscu, P. F.—Mikrophotographien iiber die Struktur und Zusammensetzung der Steinkohle des Carbon entnommen yon mikroskopischen Durchschnitten d. Steinkohle. (Microphotographs of the Structure and Composition of Coal from Microscopical Sections.) 73 photographs on 13 plates and a photographie frontispiece. Leipzig, 1882. Rogers, W. A.—On a new form of dry mounting. - Be ow) of paper read in the Microscopical Section of the Amer. Assoc. y. Sci.] - HE sues Amer. Natural., XVI. (1882) p. 1050. S., W. J.—Note on Mounting for Hot Countries. (Cf. II. (1882) p. 288—Report of satisfactory results with balsam and benzol and dammar and benzol. ] Sci.-Gossip, 1882, pp. 276-7. SARGENT, W., junr.—Bleaching Fluid for Insects. [Hydrochloric acid, 10 drops; chlorate of potash, 3 dr.; water, 10z, Soak for a day or two, Wash well.] Journ. Post. Mier. Soc., 1. (1882) p. 192. 152 SUMMARY OF CURRENT RESEARCHES, ETC. ScHIEFFERDECKER, P.—Ueber eine neue Injectionsmasse zur Conservirung der Leichen fiir dem Praparirsaal. (On a new injection-mass for preserving bodies for the preparing room.) Arch. f. Anat. u. Entwick., 1882, pp. 197-8 93 ,, Ueber die Verwendung des Celloidins in der Anatomischea Technik. (On the use of Celloidin in anatomical technics.) Arch. f. Anat. u. Entwick., 1882, pp. 199-203. Scuvutern, M.—Zur Technik der Histologie. (On histological technics.) [Post.] Zool. Anzeig., VI. (1883) pp. 21-%. Siack, H, J.—Pleasant Hours with the Microscope. [Disease Germs— Potato, Starches, &c., with Polarized Light.] Knowledge, VII. (1882), pp. 7-8, 34-5. Srirtinc, W.— The Sulphocyanides of Ammonium and Potassium as_histo- logical reagents. [Post.] Journ. Anat. § Physiol., XVII. (1883) pp. 207-10. StoweE.1, C. H.—How to preserve Urinary Deposits. [In Canada balsam, in glycerine, in a 1 per cent. solution of carbolic acid, in equal parts of glycerine and camphor-water, in a solution of naphtha and creosote, &c. Special directions as to the latter.] The Microscope, II. (1882) pp. 161-2. » ©. H.and L. K.—Microscopical Diagnosis, viii. 96, 114, 32 pp., 37, 78, and 16 figs., 10 pls. S8vo, Detroit, 1882. Taytor, T.—A new freezing Microtome. ([Supra, p. 143.] Proc. Amer. Soc. Micr., 5th Aun. Meeting, 1882, pp. 153-5 (1 fig.). TEASDALE, W.—Bleaching Leaves. [Leaves of Arabis albida bleach rapidly in chloride of lime, and give charming results. } Journ. Post. Mier. Soc., I. (1882) p. 191. VEREKER, J. G. P.—To mount in glycerine. {Heat indiarubber till it becomes sticky, dissolve it in benzol, ring both cover and slide, then let it remain till tacky ; arrange the object in glyce- rine, press down the cover, wash away spare glycerine, and run asphalte varnish or other finish. ‘The advantages are, the indiarubber sticks in spite of the glycerine, and is elastic, and so a great amount ef trouble is saved.”] : Journ. Post. Micr. Soc., I. (1882) p. 192. Wave-Witton, E.—Pond-hunting in winter. [Remarks on the importance of collecting in winter as well as summer, and notes of organisms to be obtained. | Journ. Post. Micr. Soc., I. (1882) pp. 183-5. Wa.msLey, W. H.—Some hints on the preparation and mounting of microscopic objects. 32 pp. and 16 figs. | Forms Part III. of Stowell’s ‘ Microscopical Diagnosis,’ supra.] 8vo, Detroit, 1882. Warren, R. §8.—Cleaning Diatoms. [Reply to Mr. Kitton, IL. (1882) p. 707, and agreeing that Mr. Kitton’s description of his process is very like that of the author, but that is an accidental coincidence. ] Amer, Mon. Micr, Journ,, I11. (1882) pp. 225-6. Wasse, G. M.—Continuous observation of Micro-fungi. [Inquiring for information about observing the germination of fungus-spores under the Microscope. ] Sci.- Gossip, 1882, p. 277. Wuirman, C. O.—Orientation in Microtomic Sections—The reconstruction of objects from sections—Method of reconstruction. [All in Vol. II. (1879) p. 71.] Amer, Natural., XVII. (1883) pp. 109-12. . 4 Gay 2 ‘t PROCEEDINGS OF THE SOCIETY. Meerrine or 131TH Decemper, 1882, at Kine’s Cottucz, Srranp,W.C., James GuaisHER, Esa., F.R.S., In THE CHatr. The Minutes of the meeting of 8th November last were read and confirmed, and were signed by the Chairman. The List of Donations (exclusive of exchanges) received since the last meeting was submitted, and the thanks of the Society given to the donors. From Schulze, F. E.—Ueber den Bau und die Entwickelung von Cordylophora lacustris (Allman). 52 pp., 6 pls. (4to. Leipzig, 1871.) Rabenhorst, L.—Beitrage zur naheren Kenntniss und Verbrei- tung der Alyen. Hefts land 2. 30 and 40 pp., 7 and 5 pls. (4to. Leipzig, 1863-5.) Wallich, G. C._—The North-Atlantic Sea-bed. Part 1. 106 pp., map, and 6 pls. (4to. London, 1862.) Krause, C. F. T. and W.—Handbuch der Menschlichen Ana- tomie, Nachtrage zur Allgemeinen und Microscopischen Anatomie. viii and 170 pp., 81 figs., and 1 pl. (8vo. Hannover, 1881.) Rossmassler, EH. A.— Das Siiswasser-Aquarium. 3rd ed. 96 pp., 53 figs. and 1 pl. (8vo. Leipzig, 1875.) Zaddach, HE. G.—De Apodis Cancriformis. viii and 76 pp. and 4pls. (4to. Bonne, 1841). Various reprints, including Milne Edwards’ ‘ Ascidies com- posées,’ 1839 (110 pp. and 8 pls.) ; Reichert’s ‘ Zoobotryon pellucidus,’ 1870 (106 pp. and 6 pls.); Dodel’s ‘ Ulothrixz zonata, 1876 (136 pp. and 8 pls.); Dumortier and Van Beneden’s ‘ Polypes composés d’eau douce,’ 1850 (96 pp. and 6 pls.); Zopf’s ‘ Conidienfriichte von Fumago, 1878 (75 pp. and 8 pls.); Cohn’s ‘ Untersuchungen iiber die Entwickelungsgeschichte der Mikroskopischen Algen und Pilze,’ i. (156 pp. and 6 pls.); Muller’s ‘ Classification des Lichens,’ 1862 (95 pp. and 3 pls.); De Bary and Woronin’s ‘ Morphologie und Physiologie der Pilze,’ 1864— 70, Parts 1-3, 96, 43, 36 and 95 pp., 6, 8, 6 and 6 pls.; Mobius’s ‘ Hozoon Canadense’ (20 pp. and 18 pls.); Gravenhorst’s ‘ Infusorienwelt,’ 1832 (66 pp. and 1 pl.); Brefeld’s ‘ Empusa musce and E. Aes 1871 GP PP- and 4pls.); and 12 others .._.. a Mr. Crisp. - The Chairman gave notice that the next meeting would be made special for the purpose of admitting of the nomination of Prof. P. Martin Duncan as President for a third year in succession, a proposal which he felt sure would be received with entire satisfaction. Mr. G. F. Dowdeswell read a paper on “A Minute Form of Parasitical Protophyte ” (see p. 26), descriptive of a section, exhibited 154 PROCEEDINGS OF THE SOCIETY. under a Microscope, of the lung of a mouse infected with a form of septicaemia. The Chairman thought the experiments described were very im- portant, from the fact of their having been conducted under such high powers. Investigations of this kind required an amount of time and a delicacy of manipulation which might well make the Society grateful to any one who bestowed upon them the necessary attention. He was very glad that Mr. Dowdeswell intended to continue the same line of investigation, and that he had promised they should hear the results of his further researches. Mr. Crisp exhibited (1) Martens’ Ball-jointed Microscope (Vol. I. (1882) p. 672); (2) Hartnack’s (or Recklinghausen’s) Demonstration Microscope (Ibid., p. 97) ; and (3) the latest form of Mr. E. H. Griffith’s Club Microscope (ante, p. 113). Mr. F. Kitton’s paper on “ Binocular Vision in the Study of the Diatomaceze” was read. Mr. Beck said, that with reference to the opening remarks of the author on the value of binocular over monocular vision, he could fully bear out all that had been said. A valuable means of convincing any one who was sceptical on the subject was to be found im a slide of Aulacodiscus ; and he remembered that when his brother Richard showed this diatom to Mr. Tuffen West for the first time under the binocular, that distinguished draughtsman looked at it for some time in silence, and then jumping up, exclaimed, “All the drawings of Diatomacee which I have done will have to be done over again.” Dr. Wallich said he could fully confirm the statement that nothing showed diatoms so well as the binocular. Indeed, from a study of these objects extending over many years, he could say that it was utterly impossible to see them in any other way. In one of the drawings of Hydrosira, he observed that Mr. Kitton had not noted the unsymmetrical formation consisting of a little dot which was gene- rally surrounded by a slight ridge on one side only. It occurred in Hydrosira and many of the discoidal forms, and, though often seen, he had never been able yet to detect what this peculiar structure was. It would be of advantage if some one would set to work to determine it. It seemed to him to have something to do with the communica- tion between adjacent frustules. Mr. Crisp said that Mr. Kitton had proved conclusively the superiority of the binocular, in that he had shown the true form of diatoms, which had previously been misinterpreted by most expe- rienced observers after observation with the monocular. Dr. Wallich, in reply to Mr. Badcock, stated that in examining these objects under high powers, he used the thinnest slide he could find and the thinnest cover-glass. Generally he used one of Hart- nack’s objectives; the only difficulty was to get the whole of the field illuminated, but it was not really necessary in by far the larger number of cases to use more than the central part of the field, which could always be illuminated. PROCEEDINGS OF THE SOCIETY. 155 Mr. James Smith said that, in working with high powers under the binocular, he had always found it of great advantage to use a finely-ground glass slip under the slide on which the object was mounted, Ifa 1-4th in. or a 1-8th in. were used under ordinary cir- cumstances, the black division across the field was seen, but the ground glass seemed to obliterate this entirely. He generally used a piece of very pale blue glass, ground on the upper surface. Mr. Stewart referred to the importance of approximating the back lens of the objective to the binocular prism. With the ordinary Wenham prism they were limited to powers of 400 to 500, but with the Stephenson arrangement it was quite easy to work with a 1-25th in. There seemed still to be persons who appeared to think that the binocular was a mere toy. It was, however, of really great import- ance, especially when working on an exceedingly transparent object, where the inner membranes could be seen distinctly separated from those above them; or in tracing out fine nerve-fibres, which, passing over or under each other, could be resolved in a way which was entirely impossible by any other means. Mr. Crisp pointed out the means that had been adopted for using the Wenham prism with the higher powers by fitting it into a tube which could be passed inside the objective. Mr. Beck believed they were only as yet in the infancy of the binocular Microscope, and he looked forward to the time when much more attention would be paid to its construction, and particularly to the question of ascertaining the best point at which the prism should be placed to get the full field without adventitious aid in the way of illuminators, by which improved results would no doubt be obtained. He believed that the binocular was the Microscope which would be used in the future. Dr. Wallich said that with reference to ground glass he might mention that some time ago he accidentally found some glass which had been near a guttapercha bottle of hydro-fluoric acid, the fumes of which had acted upon the glass and frosted it in a far finer manner than could be done with the finest emery powder. The condenser he used was the ordinary “Gillet,” with which he had no difficulty. Another thing which he found very useful with the bull’s-eye con- denser was to fix a piece of light-blue glass on the near side of it; the light from this was so good that he could confidently recommend the lan. 4 Dr. Gibbes said he could corroborate all that had been said on the subject of the binocular, and especially its value when used with a 1-12 in. in examining those very minute parasites to which his atten- tion had been given, as it enabled him at once to see whether they were outside or inside the tissue. Mr. Dreyfus’s Note was read, describing a safe method of packing slides in a cabinet for railway and sea transit (see p. 146). 156 PROCEEDINGS OF THE SOCIETY. The following Instruments, Objects, &c., were exhibited :— Mr. Bolton :—Pywicola affinis and Euglena oaxyuris. Mr. Crisp :—(1) Improved Griffith Club Microscope. (2) Hart- nack’s (or Recklinghausen’s) Demonstration Microscope. (3) Martens’ Ball-jointed Microscope. Mr. Dowdeswell : —Section of lung of septiceemic mouse. New Fellows :—The following were elected Ordinary Fellows :— Messrs. W. M. Bale, Abraham D. Balen, Walter H. Bulloch, C. E. Hanaman, J. Satchill Hopkins, J.P., William C. Ondaatje, L.MLS. Beng., C. H. Stearn, John L. Wall, and David Welsh. CoNVERSAZIONE. The first Conversazione of the Session was held on the 6th December last in the Libraries of King’s College, when the following objects, &c., were exhibited :— Mr. Baker: Zeiss’s Small Dissecting Stand, with Compound Objective, Large Dissecting Microscope, and Travelling Microscope. Hartnack’s Histological Microscope. Arranged Tests (Plewrosigma) in balsam. Mr. Badcock : Epistylis with Flagellata, and Lophopus crystallinus. Mr. F. P. Balkwill: 200 Foraminifera arranged and named on one slide. Mr. Blackburn : Cast skins of nymph and sub-imago of Heptagenia longicauda, one of the Ephemeride. Messrs. R. and J. Beck: New Petrological Microscope, and Bacilli in lung of cow. Mr. W. G. Cocks: Hydra vulgaris developing winter eggs. Pencil Tails (Polyxenus lagurus) and Volvow globator. Mr. A. C. Cole: Sporocarp of Pilularia globulifera in section. Mr. Creese : Pitcher of Nepenthes distillatoria showing acid glands. Mr. F. Crisp: Slides illustrating the views of Drs. Loew and Bokorny on the chemical difference between dead and living protoplasm. Mr. Curties : Notamia bursaria polarized. Mr. Dowdeswell : Nerve-fibre, showing the reticulated structure of the sheath, Mr. Enock : Tingis hystricellus from Ceylon, and Hzmatopinus suis. Mr. F. Fitch: Reproductive organs of a bee. ‘ RM NS, ag PROCEEDINGS OF THE SOCIETY. gel Lin Tf Mr. Guimaraens : Quartzite from S. America and sandstone from Cheshire, exhibited for comparison with the so-called “ Braunfels Meteorite.” Mr. Groves: Capillary network of trachez on duct of salivary gland of cock- roach. Improved Groves- Williams Ether Freezing Microtome. Dr. Gibbes: Bacillus tuberculosis in sputum, and injected human lung from a case of Acute Tuberculosis. Mr. H. F. Hailes: Arenaceous Foraminifera. Mr. Hardy: Chromatoscope. Mr. Hood : Floscularia ambigua Hudson. Mr. Ingpen: Professor Abbe’s Test-plate. Mr. Joshua : Bulbochete sessilis, and some Desmids. Dr. Millar: Mylinsia Fittelli, a Hexactinellous Sponge. Mr. Michael: Specimen of Mymar and Uropoda formicarice, a new species of predatory mite discovered by Sir John Lubbock, Bart. Mr. E. M. Nelson : Amphipleura pellucida (dry on cover), with Powell and Lealand’s oil-immersion 1-25th, N.A. 1°38 (130° in glass). Pleurosigma formosum (dry on cover), with Powell and Lealand’s low-angled dry 1-4th, N.A. *77 (100° in air). Mz. Priest : Statoblasts of two new Spongille described by Mr. Carter, S. Bombayensis and S. segregata. Messrs. Powell and Lealand : Scale of Podura with 1-20th oil-immersion, N.A. 1°38. Amphipleura pellucida with 1-12th oil-immersion, N.A. 1°43. Mr. Reed: Section of leaf of Hedychium Gardnerianum. Mr. G. Smith : Transparent photographs of rock sections by polarized light, and section of Nepheline Dolerite. Mr. J. Smith: Wing of peacock butterfly. Mr. C. H. Stearn : Microscopes illuminated by minute Swan incandescence lamps, Mr. Chas. Stewart : Botryllus sp. ? Messrs. Swift and Son : Eggs of parasite of Ground Hornbill. 158 PROCEEDINGS OF THE SOCIETY. Mr. H. J. Waddington : Lactate of copper and copper deposited by electrolysis. Mr. J. G. Walker : An undescribed British sponge; parasitic and coating. It has a new form of spicule sparsely distributed on membranes. Mr. F. H. Ward: Sections of Cycas revoluta, and dahlia root showing inulin. Mr. T. Charters White : Teeth of blow-fly, and the valve of salivary duct of blow-fly. Meetines or 107TH Janvary, 1883, ar Kine’s Cotteces, Stranp, W.C., Tur Presrpent (Proressorn P. Martiy Dvnoan, F.R.S.) mn THE CHAIR. The Minutes of the Meeting of 13th December last were read and confirmed, and were signed by the President. The List of Donations (exclusive of exchanges) received since the last meeting was submitted, and the thanks of the Society given to the donors. From Fromentel, E.de.—Introduction a l’étude des Polypiers fossiles. 357 pp. (8vo. Paris, 1858-61.) Klencke, P. F. H.—Ueber die Contagiositat der EHinge- weidewiirmer nach Versuchen und iiber das physiologische und pathologische Leben der mikroskopischen Zellen nach empirischen Thatsachen. iv. and 42 pp. (8vo. Jena, 1844.) Ziegler, M.—Lutte pour l’éxistence entre l’organisme animal et les Algues microscopiques. iv. and 80 pp. (8vo. Paris, N.D.) And 9 reprints on Milk, Foraminifera (6), Colouring Matter in Plant Cells, and ’Algse ue Mr. Crisp. Mason, J. J., M.D. ’ Minute Structure of the Central Nervous System ‘of certain Reptiles and Batrachians of America. 113 pboto- pore: Ss dame xxiv. pp. (Fol. Newport, U.S.A., 1879-82) . - ae The Author. Slide of Bugula ‘tur binata, with tentacles extended and stained Mr. H. C. Chadwick. Special attention was called by the President to the volume presented by Dr. Mason. Mr. Crisp exhibited (1) Mikulicz’s Stomach Microscope and (2) Crouch’s Portable Histological Microscope. r Mr. J. D. Hardy read a note on a method of illumination by means of the Chromatoscope (see p. 126). Mr. Stewart said that no doubt most of the Fellows who were present at their last Conversazione saw this apparatus exhibited and observed that it did most efficiently add to the beauty of objects shown, which were not amenable to the action of the polariscope. It was not demonstrated, however, that it enabled any one to find out the structure of objects better, though it certainly added to their beauty. _The President said that several of the Fellows had been in the PROCEEDINGS OF THE SOCIETY. 159 habit of using different tinted glasses, and there could be no doubt that a blue or red and perhaps even a violet glass placed on the mirror or bull’s-eye was of great use In many examinations. The violet tint seemed to be of less use than the others, because this colour was not so favourable to the eye. He had himself frequently used green with opaque illumination and found it enabled him to examine objects for a longer time than was possible by ordinary yellow light. There was, however, this important difference between the use of tinted light and polarized light, that it did not enable any one to see hidden structures which polarized light so often displayed. In corals, for instance, whilst coloured light was much better for their examination than common yellow light, yet polarized light gave an insight into their structural peculiarities—showing how the object had been originally built up—in a way which mere variety of tint was quite incapable of doing. He was glad to see this effort on the part of Mr. Hardy to add to the beauty of some of their favourite objects, especially as he felt that the attention given of late to high powers had caused the esthetics of the Microscope to become some- what neglected. Mr. J. Mayall, junr., exhibited the stage by R. B. Tolles, of Boston, U.S.A., which he thought would be of interest to the Fellows after the description of it which appeared in the Journal, I. (1881) p. 944. Mr. Beck exhibited an objective (without adjustment collar) of 1-6th in. focus, made specially for the binocular with very short setting, so that the back lens would lie close to the prism. Mr. Ingpen remarked that the difficulty of obtaining any adjust- ment for cover-glass was the great stumbling-block in the way of the manufacture of such lenses. Mr. C. H. Stearn read his paper “On the Use of Incandescence Lamps as Accessories to the Microscope” (see p. 29), the subject being illustrated by the exhibition of the arrangements. The President said he felt sure the Society was very much obliged to Mr. Stearn for having shown them this very excellent adaptation of electric lighting to the Microscope. It showed them very plainly what they would have to come to, and he hoped it pointed to a speedy annihilation of all rock-oil abominations. The great convenience of having a light so completely under command struck him as a great point about it; for in examining such objects as Echinoderms with a 2-in. objective, what was specially wanted was a light that could be twisted and twirled round the object in the way shown by Mr. Stearn. He sincerely hoped that the idea would be fully worked out, and that it would be taken up by some of their great makers. No doubt those who saw these little lamps exhibited at their last Conversazione would agree with him in thinking that it was one of the most interesting exhibitions ever brought before them. ; Mr. Stearn, in reply to questions from Mr. Beck and Mr. Crisp, said that the accumulators which were under the table in the room would work the lamps for several hours consecutively, but he was 160 PROCEEDINGS OF THE SOCIETY. unable to say how long they would last without recharging if they were put on one side, and not used for some days. He thought a good deal of the current might be dissipated meanwhile. Mr. A. D. Michael read a paper “On the Anatomy of the Oriba- tide” (see p. 1), the subject being illustrated by diagrams, and specimens shown under the Microscope. Mr. Stewart said when he considered the hardness of the cuticle of these creatures, and the softness of their internal structures, he could only express his admiration at the skill with which Mr. Michael had overcome the difficulties in the way of such investigations. Dr. G. C. Wallich read some “Notes on the Rhizopods,” pro- mising to continue the subject on a future occasion. Mr. Crisp said that the question of symbiosis between animals and plants was one which was exciting a great deal of attention, and Dr. Wallich’s remarks on the subject were of special interest. The Meeting was then declared by the President special, in pursuance of notice given at the previous meeting ; and it was then moved by Dr. Millar, and seconded by Mr. Crisp, that the bye-laws be suspended to enable the Council to nominate the President for election to a further term of office. The proposal having been put to the meeting, was carried unani- mously. Mr. Crisp read a list of Fellows who had been nominated by the Council for election at the February meeting as Officers and Council for the ensuing year. Mr. Badcock and Mr. Curties were elected Auditors of the Treasurer’s accounts. The following Instruments, Objects, &c., were exhibited :— Mr. Beck—Short 1-6th in. Objective for Binoculars. Mr. Bolton—Rhipidodendron Hualeyi. Mr. Chadwick—Bugula turbinata. Mr. Crisp ~—(1) Crouch’s Portable Histological Microscope. (2) Miculicz’s Stomach Microscope. Mr. Groves—Martens’ Ball-jointed Microscope. Mr, Hardy—Chromatoscope. Mr. J. Mayall, junr.—Tolles’ Stage. Mr. Michael—Slides illustrating the Anatomy of the Oribatide. Mr. C. H. Stearn—Apparatus for Electrical Illumination by Incandescence. New Fellows.—The following were elected Ordinary Fellows :— Messrs. John E. Fawcett, Arthur 8. Pennington, Samuel A. M. Satow, C. H. Trinks, Arthur W. Waters; and as Ex-officio Fellow, the President for the time being of the Essex Field Club. Water W. Reeves, Assist,-Secretary. aa ( 18 ) & J. BE OK. MANUFACTURING OPTICIANS. 68, CORNHILL, LONDON, E.C. 1016, CHESTNUT ST., PHILADELPHIA, U.S.A, FACTORY : | LISTER WORKS, HOLLOWAY, LONDON, N. “MICROSCOPES, MICROSCOPE OBJECT-GLASSES, : PATHOLOGICAL AND PHYSIOLOGICAL PREPARATIONS, : Materials and Instruments for Mounting | Objects, and for Students’ Use. ILLUSTRATED CATALOGUES ___._-* DESCRIPTIVE PAMPHLETS = Of the Cheaper Forms of Microscopes forwarded upon ae Application to e R. & J. BECK, ___ 68, CORNHILL, LONDON, E.C._ ( 14 ) JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY, Containing fits Crangattions and Proceedings, ay AND A SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY (principally Invertebrata and Cryptogamia), MICROSCOPY, &c. Edited aby Frang Crisp, LL.B., B.A., one of the Secretaries of the Society and’a Vice-President and Treasurer of the ai Linnean Society of London ; WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND A. W. Bennett, M.A., B:Sc., F. JEFFREY Bett, M.A., Lecturer on Botany at St. Thomas’s Hospital, | Professor of Comparative Anatomy in King’s College, S. O. Ripiey, M.A., of the British Museum, and JonN MayAt1, Jun., FELLOWS OF THE SOCIETY. Txu1s Journal is published bi-monthly, on the second Wednesday of the months of February, April, June, August, October, and December, It varies in size, according to convenience, but does not contain less than ~ 9 sheets (144 pp.) with Plates and Woodcuts as required. The price to non-Fellows is 5s. per Number. The Journal comprises: (1.) The TRANSACTIONS and the ProcEEDINGS of the Society: being the Papers read and Reports of the business trans- acted at the Meetings of the Society, including any observations or discussions on the subjects brought — 5 forward. (2.) Summary of CurRRENT RESEARCHES relating to ZooLoey ~ and Botany (principally Invertebrata and Cryptogamia, with the Embryology and Histology of the higher Animals. and Plants), and Microscopy (properly so called): being — abstracts of or extracts from the more important of the — articles relating to the above subjects contained in the — various British and Foreign Journals, Transactions, ry. from time to time added to the Library. Aes Authors of Papers printed in the Transactions are entitled to 20 cies, ‘ of their communications gratis. Extra copies can be had at the price o 12s, 6d. per half-sheet of 8 pages, or less, including cover, for a minimum ~ iS number of 100 copies, and 6s. per 100 plates, if plain. Prepayment. by P.0.0. is requested. All communications as to the Journal should be addraeieas to fhe Editor, Royal Microscopical Society, King’s College, Strand, W.C.. Published Jor the Society by WILLIAMS AND NORGATE, LONDON AND EDINBURGH. tee ox is . > Ae ee er LN . ay y Se A sey se an ea eas ( 15 ) EIESPERVUS LAMP, WITH EXTINGUISHER. EQUAL TO 45 CANDLES. Prize Medals—PARIS, THREE MEDALS, 1878. MANUFACTURED BY JONES & WILLIS, Patentees, 43, Great Russell Street, and 260, Euston Road, London, and Temple Row, Birmingham, The most brilliant and economical mode of illumination adapted to public and doniestic use, There is no lamp comparable to it for brilliantly giving three beautiful and vigorous flames of light. The wicks being in a triangular form, each wick is supplied with a separate thumb-screw,by which it can be either elevated or depressed. The illuminating power is 45 Candles, and the consumption of oil less in pro- portion than the Duplex, or any other Paraffine Lamp. THIS LAMP, SUITABLE FOR MIGROSCOPISTS, CAN BE SUPPLIED ON A LOWER STAND. Show-Rooms: 43, GREAT RUSSELL STREET, W.C. Works: 260, EUSTON ROAD, N.W. W. EMIL BOECKER, “MANUFACTURING OPTICIAN, WETZLAR, GERMANY, SENDS GRATIS HIS CATALOGUE OF MICROSCOPES, OBJECTIVES, MICROTOMES, AND APPARATUS FOR Scien Eee ee Sis) Heinr. Boscker s Microscopical Institute, at Wetzlar, Germany, SUPPLIES _MICROSCOPICAL PREPARATIONS In al branches of Natural History.. “A: ‘Large Selection of Injections, Stained Preparations, Insects, Crustacea, pintozes, and Lower Animals; Vegetable Anatomy, Woods, Articles of Food, Alg@, Mosses, Fungi, Digtoine, ~ and Sections of Rocks and Fossils. Instruments and Appliances for Mounting, &c. Sciopticon, with addi- ee for using microscopic objectives. Glass Photograms. Catalogue No. i, Gratis and Post-free. “THE BRITISH Moss. FLORA. By R. BRAITHWAITE, M.D. Piet . VL is now ready, price 4e. Subseriptions (10s. 6d.) may be sent to the . or ( 16 ) W. WATSON & SON’S . NEW MICROSCOPE STAND (PATENTED), - The most perfect Instrument for the employment of light at great x angle of f obliquity ever introduced. es W. & S.’s PATENT MECHANICAL STAGE ¥ Is graduated to degrees—Rotates concentric, and will revolve completely round, withany ~ instrument—has mechanical movements in vertical, horizontal, and oblique directions, — and is the thinnest and most perfect mechanical stage ever introduced. Be, See description in the Royal Microscopical Journal, April and June, 1881. Illustrated Catalogue of above, and all descriptions of Microscopes and Apparatus, post free 2d. ‘W. WATSON & SONS, 318, High Holborn, London, W.C. 4 LO MICROSC OPIS fs; * PREPARATIONS OF FRESH WATER ALGZ, re Including Desmiprem, DiaTomMAces, and CEDoGONIE®; also Funet, Mosszs, &e., showing well their Structural Development and Mode of Reproduction, 15s. per doz. slides. A few very good sets of Opaque Licuens, suitable for low powers with the Binocular. These will have especial interest to the Student, showing the true character of the thallus, its colour and mode of growth, and ag type specimens from which Herbaria may _ be named will be invaluable. $ Appty; W. JOSHUA, F.L.S., CIRENCESTER. % New and Second-hand Microscopes, Objectives, and Accessories. — A Large Assortment by Ross, Beck, Cottins, Swit, and other first-class Makers, on Sale, A) ata GREAT REDUCTION IN PRICE. eG MICROSCOPICAL OBJECTS in great variety. Spécialité. PuystoLocicaL and PATHOLOGICAL TISSUES, | A choice variety of prepared Physiological Sections ready for Mounting. Ny PHOTOGRAPHIC LENSES, CAMERAS, and APPARATUS, by Ross, DaLiuerer, and all other esteemed Makers, Largest, Cheapest, and Best Stock in London. New CATALOGUES Post 28 HUNTER & SANDS, 20, CRANBOURN STREET, LONDON. af = e LIVING SPECIMENS FOR THE MICROSCOPE. | = we THOMAS BOLTON, 357, Newhall Street, Birmingham. SPECIMEN TUBE, ONE SHILLING. A Series of TWENTY-srx TuBEs in course of Six Months (or as required) for a SUBSCRIPTION, in advance, of £1 1s. Portfolio of Drawings, Hight Parts, One Shilling each. Hints on the Preservation of Living Objects, and their Examination under the Bier eaeoRs, 3d. UNMOUNTED OBJECTS FOR THE MICROSCOPE. PREPARED FOR MOUNTING, WITH INSTRUCTIONS, : Will be ready immediately— Series D*—24 Australian Zoophytes. Series E*—12 Palates of Mollusca: Series F*—24 Mosses and Hepatics. PRICE 2s. EACH SERIES, POST-FREE, 2s, 1d. Brown Cement, the best for Microscopic Work, post-free, 1s. 3d. Every requisite for Microscopic work. EDWARD WARD, 29, BURLINGTON STREET, OXFORD ROAD, MANCHESTER. MICRO-PETROLOGY.— A Large Series of Rock Sections, comprising Anamesite, Aplite, Basalt, Diabase, — Diorite, Dolerite, Elvans, Gabbro, Gneiss, Granite, Granulite, Lava, Ses Liparite, Napoleonite, Neppelirite, Obsidian, Pikrite, Porphyry, PROnCHIG a Quartzite, Rhyolite, Syenite, Tachylite, &c., 1s. 6d. and 2s. each, Sections of Organic Rocks, showing Foraminifera, Boon Structure, Corals, Shells, be, THOMAS D. RUSSELL, 48, Essex Street, Strand, Wee neat SEES va eis fs ( WW ) - International Exhibition Prize Medals and Awards, 1851, 1855, 1862, 1873, 1878; and The Imperial Austrian Francis Joseph Order, for Excellence and Cheapness. ML. PILLISCHER’S NEW MICROSCOPE, “THE INTERNATIONAL,” - Is farnished with B and C Hye-pieces; a 5-8 and 1-7 Object-glasses of high defining nia penetrating quality, combining (by a draw-tube) a series of eight different powers, from 50 to 420 diameters; bull’s-eye con- denser; revolving diaphragm; pair of tweezers; plate- "Els See and thin ee plese, "and a well-made “be “mahogany box, 10 by 6 by 4, with lock and key .. . .. Price £7 10s. _ . With the addition of A Eye-piece, 14 or 2 in. Object-glass, Polarising a jaaebad ‘and Selenite, and a Camera Lucida.. . -. Price £10 10s. And all the Apparatus and ‘Accessories, as described above, with the addition of a D Bye-piece and a-1-9 Object-glass, giving a series of twenty- -eight masotiving powers, from 15 to 1000 diameters .. .. Price £14 Os. A Glass Stage, to prevent the instrument from being affected by the use of corrosive chemicals, to any of the above instruments, extra 6. 2. +s ++ ee ae we 12s. Gd. Illustrated Descriptive Catalogue on application to ss, NEW BOND STREET, LONDON, Ww. MICROSCOPICAL SPECIALITIES, ILLUSTRATING THE STRUCTURE, GROWTH, AND REPRODUCTION OF PLANTS. SPECIAL EDUCATIONAL SETS, illustrating Sachs’ and Thomé’s Text-Books of Botany, the preparations being copies of figures in those works. A large assortment of miscellaneous Botanical Objects. Test Diatoms mounted in Monobromide of Napthaline. x Chas. V. Smith, Carmarthen. p: SPECIAL [AL NWOTICE- “POWELL AND LEALAND’S NEW OIL IMMERSION CONDENSER can be adapted to any Microscope, and resolves all the most difficult test objects—price a Two Guineas. MICROSCOPES from £11 11s. to £200. cod ‘The £11 11s. Instrument consists of 1-inch and 3-inch Object-glasses, with Apertures of 30 and.95 deg. respectively, coarse and fine Adjustment, Glass Stage and Bull’s-eye x Condenser, fitted in mahogany case, and is most suitable for Students, Brewers, &c. a WATER AND OIL IMMERSION LENSES. aan 170, EUSTON ROAD, LONDON, N.W. . CHAS. COLLINS’ ‘ q | STO LOGICAL MICROSCOPE, oe . With 1-inch and }-inch Objectives of splendid Definition, _Eye-piece, and Case, £5 10s. Full particulars free per post. “ "Have Binocular Microcrres Dissecting Microscopes, Lamps, Objectives, Thin Glass Bers Slips, Mediums, and every requisite for the Study. Ps ia : oe a THIRTY- ‘SIX. PAGE ILLUSTRATED CATALOGUE ON APPLICATION, CHARLES COLLINS, “A157, eet Portland Street, London, Ww. ae —- ; ae P. Comune? Science Book Depot, adjoining the above. Catalogue on application. C 18 ) MICROSCOPIC OBIEHCTS.- Classified Catalogue. . NEW EDITION FOR 1880. Post Free and Gratis, A Specimens of the highest attainable perfection in every branch of Microscopy. New and Rare Diatomacee. Test and Binocular Objects. Moller’s Typen Plattes. Microscopes, Achromatic Objectives, and all Materials and Instruments for Mounting. EDMUND WHEELER, 48B, Tollington Road, Holloway, London, N. NATURAL HISTORY AND GENERAL SCIENCE. : THE LARGEST COLLECTION OF SECOND-HAND WORKS RELATING TO THE ABOVE. CATALOGUES TO BE HAD OF JOHN WHELDON, 58, Great Queen Street, London, W.C. A new Zoological List will be published shortly, post-free Three Stamps. SWHLET & SON pe Are now adapting to their ‘* Challenge ”’ and other Microscopes, 2 A NEW THIN MECHANICAL STAGE AND PATENT COARSE AND 4 FINE ADJUSTMENTS, Also SWINGING SUBSTAGE RADIAL ILLUMINATOR, as well as all the latest Improvements and Additions to the Microscope. Catalogue fully Illustrated, and Circular, containing particulars of the above, by post ae for six stamps, or mailed abroad free. UNIVERSITY OPTICAL WORKS, 81, TOTTENHAM COURT ROAD, LONDON, W.C. (formerly of 43, University Street). NOW PUBLISHING. STUDIES IN MICROSCOPICAL SCIENCE. wa Edited by ARTHUR C. COLE, F.R.MS., &c., assisted by several Eminent Specialists. 2 aa es RN ENE Oe CS i ee ete “ te Ms ZA e re A WEEELY Pertopicar for the use of Students, Teachers, Professors, and the Medical Profession, and others ~~ interested in the progress of the Natural Sciences, Each Number is illustrated and accompanied by— (1) A Microscopical preparation of the highest class and most perfect finish; (2) A description of the Speci-~ J” men, the methods of its preparation asa means of Study, the literature concerning it, &c.;.(3) A Chromo- ~~ lithographed, Photographed, or Engraved drawing or diagram of the Object, in the exccution of- which — Scientific accuracy and artistic detail are specially observed. po The terms of subscription, payable strictly in advance, including Postage, are—In Great Britain, Quarterly, 1l, 4s,; Half-yearly, 21. 4s.; Yearly, 41. 4s. Abroad, to Countries within Postal Union, Quarterly, ll. 6s. 64 3 Half-yearly, 21. 88,5 Yearly, 41. 12s. 6d. Those desirous of receiving a smaller number of Specimens, and i fortnightly, may, for 21. 2s. a year, receive either the series of 26 HisroLocicAL PREPARATIONS or the 26 BOTANICAL and PETROLOGICAL SEcTIONS, together with their accompanying essays and illustrations. Sica Rp) < Subscription will be 2/. 6s. 6d.) = ae ; Subscriptions to the Editor, Mr, A. C. Cote, St. Domingo House, Oxford Gardens, London, W. JAMES HOW & CO. SUCCESSORS TO GEO. KNIGHT & SONS, 73, FARRINGDON ST. (late of 2, Foster Lane, and 5, St. Bride St). HOW’S. MICROSCOPE LAMP. THE MINIATURE MICROSCOPE LAMP. a HOW’S STUDENTS’ MICROSCOPE, £5 5s. THE POPULAR BINOCULAR MICROSCOPE, £12 ay Rock SECTIONS AND OTHER Microscopic Oxpsecrs. - MR. FRED. EBNOC K, PREPARER OF MICROSCOPIC OBJECTS, . Late of 30, Russell Road, Seven Sisters’ Road, London, Me HAS REMOVED TO On MARCH Ist, 1883, Will be ready, and may be had of all Booksellers, Price 1/6, PART 5 (BEING THE FIRST PART OF You. 2,) THE Fournal of the Postal Microscopical Society. Amongst other interesting subjects, it will contain Papers on The Conduct of Scientific Inquiry. Notes on the Exhibition of Magnified Objects. The Maggot of the Blow-Fly. The Microscope in Medicine, A Method of Making and Mounting Transparent Rock-Sections for Microscopic Slides. Mounting Diatoms in Lines and Patterns. Photo-Micrography. Hali-an-Hour at the Microscope with Mr. Tuffen West, in which the following objects are discussed :— Polystomella crispa and P. umbilicatula, Antenne of Insects, Stomach of Blow-Fly, Flea from Cat, Saws of the Saw-Fly, Sting of Sand-Wasp, Acarus from Finch, Hypopus muscarum, Gamasus from House-Fly, Gamasus colecptratorum, Gamasus from Rat, Dermanyssus. Selected Notes from the Society’s Note-Books. Reviews, etc. etc. Six Lithographic Plates and a number of Wood Engravings. Strong Cloth Cases for Binding Vol. I. may also be had, price 1/6. [Vol. L., handsomely bound in Cloth, Gilt, Bevelled Edges, may be had of Publishers only, Post Free, 8/-.] W. P. COLLINS, SCIENCE BOOKSELLER, 157, GT. PORTLAND ST., LONDON, W. NOW READY, VOL. I. OF THE Fournal of the Postal Microscopical Society, Handsomely Bound in Cloth, Gilt, Bevelled Edges, Price, 7/6; Post Free, 8/- The following are some of the Articles contained— History of the Postal Microscopical Society. Numerical Aperture. The Microscopical Examination of Chlorophyll, Inulin, and Frotein Crystals. Tubifex Rivulorum. How to Prepare Foraminifera. 2 Papers. Lichens. Diatoms. An Hour at the Microscope, with Mr. Tuffen West. 3 Papers. A Supposed New Species of Caligus. Cutting Sections of Soft Tissues. Spiders, their Structure and Habits. 2 Papers, Holothurian Plates, from the Carboniferous Strata of the West of Scotland. Hydrozoa and Polyzoa, Photo-Micrography. Stylaria Paludosa. Larva of Tanypus Maculatus. New Method of Preparing Minute Microscopic-Organisms, The Embryology of the Stalk-eyed Crustacea. Adulteration of Coffee and the Microscope. Unpressed Mounting for the Microscope. Aquaria for Microscopic Life. The Structure and Economy of the Daphnia. The Size of Dust Particles of Wheat and Coal, Notes on the Bursting-point cf some Starch-cells. Pond Hunting in Winter. Selected Notes from the Society’s Ncte Books, 4 Papers, Etc. Ete. 19 Lithographic Plates, including a large Map, and numerous Engravings. LONDON: W. P. COLLINS, Science BOOKSELLER, No. 157, Great Portland Street, London, W. BATH : No. 1, CAMBRIDGE PLACE. i =n ~ (19 ) be Medal and Highest Award, Great Exhibition, London, 1851. ' Gold Medal, Paris Exposition, 1867. Medal and Highest Award, Exhibition, London, 1862, Medal and Diploma, Centennial Exhibition, Philadelphia, 1876. Medal and Diploma, Antwerp, 1878. Gold Medal and Diploma, Paris Exposition, 1878. Medal, Highest Award, Br eney 1879, ROSS & CO., MANUFACTURING OPTICIANS, 112, NEW BOND STREET (FACTORY, BROOK STREET), LONDON, W. MICROSCOPES, OBJECT-GLASSES, APPARATUS, MICROSCOPIC PREPARATIONS. DESCRIPTIVE CATALOGUE ON APPLICATION TO fa ROSS & CO. n 2, NEW BOND STREET, w. ie (One door from Brook Street), REMOVED FROM 164, NEW BOND STREET. ESTABLISHED 18380, / | ‘Biological or other subjects of Microscopical Research. oe Strand, iia THE ROYAL MICROSCOPICAL SOCIETY (Founded in 1839. Incorporated by Royal Charter in 1866.) The Society was established for the communication and discussi of observations and discoveries (1) tending to improvements in the ce struction and mode of application of the Microscope, or (2) Tol It consists of Ordinary, Honorary, and Ex-ofiicio Fellows. Ordinary Fellows are elected on a Certificate of Recommenda signed by three Fellows, stating the names, residence, description, & the Candidate, of whom one of the proposers must have personal km ledge. The Certificate is read at a Monthly Meeting, and the Candi balloted for at’the succeeding Meeting. The Annual Subscription is 21. 2s., payable in advance on electi and subsequently on Ist January. annually, with an Entrance Fee of 21, Future payments of the former may be compounded for at any time- 311.108. Fellows elected at a meeting subsequent to that in February only called upon for a proportionate part of the first year’s subseripti and Fellows absent from the United Kingdom for a year, or permanent residing abroad, are exempt from one-half the subscription during absence, ee Honorary Fellows (limited to 50), consisting of persons eminent in Microscopical or Biological Science, are elected on the recommendatior a of three Fellows and the approval of the Council. (a Ex-officio Fellows (limited to 100) consist of the Presidents the time being of such Societies at home and abroad as the Council m recommend and a Monthly Meeting approve. They are entitled to ree the Society’s Publications, and to exercise all other privileges of Fell except voting, but are not required to pay any Entrance Fee or A Subscription. The Council, in whom the management of the affairs of the Sc is vested, is elected annually, and is composed of the President, four V: Prosidents, Treasurer, two Secretaries, and twelve other Fellows. 3 _ The Meetings are held on the second Wednesday in each m from October to June, in the Society’s Library at King’s College, ‘Strand W.C. (commencing at 8 p.u.). Visitors are admitted by the introductic : Fellows. % In each Session two additional evenings are devoted to the exhib: 0 of Instruments, Apparatus, and Objects of novelty or interest relating ti the Microscope or the subjects of Microscopical Research. a The Journal, containing the Transactions and Proceedings of h Society, with a Summary of Current Researches relating to Zoology D Botany fernelpeny Invertebrata and Cryptogamia), Microscopy, published bi-monthly, and is forwarded gratis to all Ordinary ape ' Fellows residing in countries within the Postal Union.” — Ai, The Library, with the Instruments, Apparatus, and Ca . Objects, is open for the use of Fellows on Mondays, Tuesdays, Thursday and Fridays, from 11 a.m. to 4 p.m., and on Wednesdays from 7 to 10 It is closed during August. Forms of proposal for Fellowship, and any further information, may be application to the Secretaries, or Assistant-Secretary, at the Library of the Secei- ~~ The Journal is issued on the second Wednesday of February, April, June, August, October, and December. | APRIL, 1883. {fo Non Fellows, “ ol. III. Part 2. JOURNAL | ROYAL. -MICROSCOPICAL SOCIETY: CONTAINING ITs TRANSACTIONS AND. PROCEEDINGS, AND A SUMMARY. OF cORRENT "ee cae RELATING TO ee AND BOTANY (prineipally Invertebrata and Cryptogamia), MICROSCOPY, éc. 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 ; Sk : | WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND A. W. BENNETT, M.A., B.Sc., F, JEFFREY BELL, M. A. urer on Botany at St, Taye Hospital, Professor of Comparative Anatomy in King’s College, $0. RIDLEY, M.A., of the British Museum, asp JOHN MAYALL, Jun. FELLOWS OF THE SOCIETY. WILLIAMS & Wopekrte, LONDON AND EDINBURGH. . CLOWES AND SONS, LIMITED,] [STAMFORD STREET AND CHARING CROSS. Fes ye JOURNAL OF THE ROYAL MICROSCOPICAL SOCIRTY. — Sern 2 Vor. ii: PART 2: (APRIL, 1883.) CONTENTS. ——079400— TRANSACTIONS OF THE SooleTy— a IV.—Five New Fuosovtus; with A Nore on Pros. Lerpy’s GENERA or Acyotus AND DioryorHora. By C. T. Hudson, LL.D., F.R.M.S. (Plates III. and IV. and figs. 31 and 82)... V.—Tue Presment’s Appress. By Prof. P. Martin Duncan, MB. Lond., E.R.S. .. oe ee ee ee oe oe e ee e VI.—Tuz Aotion or Tannin on THE Cra or InFusoRIA, WITH REMARES ON THE USE OF SOLUTION or SuLPHUROUS OXIDE IN _ Auconon. By Henry J. Waddington, (Figs. 33 and 34).. Summary oF CurRRENT RESEARCHES RELATING TO ZOOLOGY AND Borany (PRINCIPALLY INVERTEBRATA AND Cryprocamta), Micro- SooPY, &c., INCLUDING ORIGINAL CoMMUNIOATIONS FROM FELLOWS | AND OTHERS ee ee oe es ee ee ee oe oe oo ZOOLOGY. Development of the Ovum of Arvicola arvalis.. +0 «s+ as Formation of the Embryonic Layers in the Trout .. 2 ee Distinctions between Organisms and Minerals Pe sera eH Development of Reproductive Organs of Pulmonate Mollusca... Developmental History of the Prosobranchiata «2 «1 we ws Norwegian Buocinidaa ie se i ae, og as) oe tg ep eee Binisigera ova ~ os ; Green Colour of Oystera OHN, Mavatn, Esq., Jun. Aupert D, Micaauz, -Esq., FLL. S. - Joun Mizar, Esq., LRP. Edin., BLS. Wiaiam Tuomas Surrorn, Esq. _ Freperics H. Warp, Esq., M.R.CS. fe) I. Numerical Aperture Table. The “ APERTURE” of an optical instrument indicates its greater or less capacity for receiving rays from the object and transmitting them to the image, and the aperture of a Microscope objective is therefore determined the ratio between its focal length and the diameter of the emergent pencil at the plane of its emergence—that is, the utilized diameter of a single-lens objective or of the back lens of acompound objective. 2 Oe ae This ratio is expressed for all media and in all cases by n sin u, n being the refractive index of the medium and u the semi-angle of aperture. The value of m sin wu for any particular case is the ‘‘ numerical aperture” of the objective. Diameters of the Angle of Aperture (= 2 u). : Theoretical P ae Back Lenses of various Biasrdal hee OL e eed Mlumi- Resolving trating 3 Dry and Immersion ‘Ancetire: Dr | . Water- | Homogeneous- nating | __ Power, in_ Powers Objectives of the same pe Me e. bi ¥ | Immersion) Immersion | Power. | Lines to an Inch. peer Power (¢ in.) (nsinw=a.) | Objectives. | Onicctives.| Objectives. | (a%.) | (A=0°5269 4 (ay a from 0-50 to 1°52.N. A. (M=1) | =1°33.)) (n= 1°52.) | =line E.). “|. NaZ ie See eer ee ——_ —_— ee oe / | > ee 1-52 | ve oe 180° 0’ | 2°310 146,528 fs eT Beg ware "| 161° 23’ 2-250) 144,600 182 hea eee 5 153° 39’ 2-190) 142,672 wo 1-46 | 147° 42’ 2-132) 140,744 1:44 | Ss ie 142° 40’ 2:074 | 138,816 1:42 *2 er 138°. 12’ | 2-016 136,838 1:40 | ss oe 134° 10’ .1:°960 134,960 - 1°38 ee ne 130° 26’ | 1-904 133, 032 1°36 oe = 126° 57’ | 1:850 131,104 1:34 ¥ of 123° 40’ 1°796 129,176 1°33 os 180°. 0’} 122° 6’ }1°770)|. 128,212 1°32 | Se 165° 56’; 120° 33 | 1-742 127,248 1°30 | Tr | 155° 38’) 117° 34! 1-690 125,320 1°28 ae | 148° 28’. 114° 44’ | 1-638 125 ,392 1:26. | ae | 142° 39°) 111° 59’-| 1°588 121,464 : 1:24 ae 137° 36’| 109° 20° | 1538 119,536 1:22 Se | 133° 4’; 106° 45’ | 1°488 117,608 ~ 1-20 5 | 128° 55’; 104° 15’ | 1-440 115,680 1:18 aa 125° 3’) 101° 50’.| 1°392 113,752 “8 1°16 == 121° 26’; 99° 29’ | 1°346 111,824 | <8 1:14 Ss 118° 00'| 97° 11’ | 1-300 109,896 1:12 zs 114° 44’| 94° 56’ (1°254) 107,948 : 1:10 : 111° 36, 92° 43’ | 1-210 106,040. = 1:08 ; 108° 36’; 90° 33° 1:166 104,112 1:06 ve 105° 42’; — 88° 26" | 1-124 102,184 . 1:04 re 102° 53’). 86° 21’ |1°082| 100,256. |~ > 1-02 $% 100° 10’) . 84° 18’ | 1°040 98,328 - 3 1:00 180° 0’ | 97° 31’; 82° 17' |1:000|} — 96,400 0:98 157° 2’ | 94° 56} 80° 17’ | -960 94,472 |. 0:96 147° 29'°| 92°.24'| 78° 20") °922 92,544 . 0:94 140° 6’ | 89° 56’| ~ 76° 24’ |. +884 90,616 ; 0:92 133° 51’ | 87°32’) 74° 30’| +846 88,688- ; 0-90 128° 19’ |. 85° 10’) 72° 36! | +810 86,760 | © 0-88 128° .1'7''|.. 82°. 51} 70° 44? | -=*774 832 0:86 118° 38’ | 80° 34’|° -68° 54’ |- +740 : 0:84 1149-17") 78°: 20’) 67°. 6! |'=:706 0:82 110° 10’ |- 76° 8’). 65° 18’ | --672 j = 0:80 | 106° 16’ | 73° 58’| 63° 31’ -640 0:78 ; 102° 31’! 71° 49’) 61° 45’ | -608 0°76 98° 56’ | 69° 42") 60° 0’ | +578 0:74 95° 28' | 67° 36'| 58° 16" |- +548 \ 0:72 92° 6! | 65° 82’| - 56° 32’ | .-518 “70 : 0-70 88° 51’ | 63° 81’) 54° 50’ | .°490 cee 0:68 - 85° 41’ |.-61° 30'| 53° 39" a ; 0°66 82° 36’: | 69° 30'| 51°. 28" ; 0:64 79° 35! | 57° 31'| 49° 48’ Sst 0°62 _ 76° 38’ | 55° 34’) 48°. -9" 0-60. 73° 44' | 53° 38’) 46° 30" |- “> 068 > 70° 54’ | 51° 42’; 44° 51’ cl OOO 68°. 6’ | 49° 48") | 43°. 14' : 0:54 65° 22" | 47° 54’| 41° 37' | +292 ; «| 952 - | 6240’ | 46° 2!) 40° 0" | -270} = 0°50 60° 0’ | 44° 10’| 38° 24’ | +250; Tixaupie.—The apertures of four objectives, two of which are dry, one water-immersion, and one r ~ > would be canpared on the angular aperture view as follows :—106° (air), 157° (air), 142° (water), 30° (0 _ [heir actual apertures are, however, a& abs baat mei. NRTA. TE pA 28 Ses ~ numerical apertures. : ; : a «Any showing elation of limetres, ;0 Inches. ' ey —ad e =) a eee PEEEEt ETL eeLeterleELELILIictriiriy Lana Poe ee ere ad a BRERURBAZRaS a a en TEE ELELEFELT | TTT RELL DELL ELD DULCE oh ae EEE eT ented ees =| Erineive 1000 (=1mm.) a SOON OMP WOR =e IT. Co) Conversion of British and Metric Measures. ins, *000039 *000079 “000118 *000157 *000197 *000236 *000276 -000315 -000354 70003894 “000433 000472 -+000512 -000551 “000591 -000630 “000669 “000709 “000748 “000787 *000827 *000866 - *000906 *000945 *000984 | “001024 --001063 -001102 -001142 -001181 -001220 “001260 “001299 “001339 -001378 “001417 “001457 “001496 “001535 *001575. “001614 “001654 “001693 001732 *001772 “001811 -001850 *001890 “001929. ~ +001969 “+ 002362 *002756 |. 003150 003543 “003937 “007874 011811 015748 | 019685 | mm, 69 70 (7-cm.) 71 ; 89 < 90 (9 cm.) 91 MNPNWNNWNMNNNh NNNWNWNNNHNDY EP ED Ed HED ED EOD EDO CODED CO OD CD CD DO HO DD POO bD ins. *007892 047262 086633 126003 *165374 “204744 244115 “283485 *322855 862226 401596 “440967 480837 *919708 +959078 “598449 *637819 bo *716560 “790930 “795301 834671 874042 “913412 “952782 -999153 “031523 “070894 “110264 -149635 *189005 *228379 267746 307116 346487 385857 425228 "464598 *503968 *943339 *582709 3°818932 3858302 3°897673 100 (10 cm,=1 decim.) ins. 3: 937043 7: 874086 11*°811130 15°748173 19°685216 23° 622259 27 7959302 31°496346 1.) LinEAt. Micromillimetres, Fe., into Inches, Fe. mm, ins. 1 *039370. 2 078741 3 *118111 4 °157482 5 *196852 6 *236223 7” *275093 § 314963 9 °304334 10 (lem.) °*393704 11. *433075 12 "472445 13 *511816 14 “551186 15 *590556 16 *629927 17 *669297 18 *708668 19 *748038 20 em.) *787409 21 *826779 22 “866150 23 *905520 24 *944890 25 *984261 | 26 1:023631 27 1°063002 28 1°102372 29 1°141743 30 (3. em.) 1°181113 ol 1:220483 o2 1°259854 83 1:299224 84 1°338595 35 1°377965 36 1°417336 37 1:456706 38 1°496076 39 1°535447 40 4 em.) 1°574817 41 _ 1°614188 AQ - 1°653558 43 1°692929 44 1°732299 45 _1°771669 46 » 1:811040 47 1°850410 48 - 1°889781 49 ~~ -1:929151 50 ( em.) 1°968522 decim. 4 2 3 4 5 6 re 4 . 8 9 =) 35433389 - 10 (1 metre) 39°370432 | 3°280869 ft. 1°093623 yds. “677189 - Inches, &c., into Micromillimetres, “th Pe) PL) ee) MAL) PLS) alnppowle els ale blnaivalElealolel- ee Hehs| He wales =) ie OOIGP NE wr esPalss Lyd: gc. 1 1 2 1 1 os 2 3 3 4 5) 6° 8 2 4) B *015991 * 269989 *693318 539977 *822197 *174972 *628539 *233295 "079954 349943 "466591 “699886 "899772 mm. 028222 *031750 *036285 042333 *050800 *056444 *063499 *072571 Se TONNE HEHE ONO RwWN Dee ee 1 1 2 2 2 2 3 * 084666 *101599 *126999 *169332 * 253998 *507995 *015991 *269989 “987486: *693318 *116648 “539977 * 174972 *233295 *762457 *079954 349943 *937429 - *524915 cm. ~ 111240 *269989 *428737 -587486 *746234 *904983 *063732 222480 381229 539977 079954 *619932 decim, *015991 *269989 "523986 “771984 *031982 *285979 *539977 "7193978 - - “047973 metres. *914392 ~~ ice) ~~ on “yeeres-2 (20.1) -“goulureZvo9p “ITOAR G686LE-9 | *SOULUVAD C686LP-9 906TE8-S 9T6E8L-S LOGSES-F LE6L88 +S 846686 +E 8S616E-% 696EF6-T 6L6966- 1 *souLUBAS ep S686LT-9 900TE8 +S 9T6E8L-S LB6GES-F LE6L88 -& 8h6686°E SS6L6E +6 696EP6-T 6L6666- 1 “SOU B.131}U00 C686LF-9 9U6TES-S 9T6E8T-S LO6SES +b LE6L88 +S 8h66E6-E SG6L6G +3 696EF6.- T 6L6966-T G86L49- *SOULULDID |] [TOT ‘of ‘sommpubypy o7ue ’ “op | 9gg¢0g-% LEP “MOAB “SQT FOGLE +S 00T 6ELZCE - - A DH 6 ED OD i 60. 80- LO» 90- G0. ¥0- 60- G0. 10- ‘sa “110A °ZO T 6FSZEP- ST FIT688- ST 6L8GFE 31 9608 - OL 60F6S6-6 PLIOTL-L 6E6ZLT-9 COL6Z9-F OLF980+& CSGEPG +1 we ANH OF-DaS T1688. 1 88ChE6-T $92080-T LP6S26- LIOTLL FEZLIO- OLEZIP- L¥9808- - (x801T D- (-180j00q 1) 000 Cxsvoop T) —- O01 (13 1) AAMHOOnR NAS *SOUULIBIBIOOp C1s1090p T) 00 06 08 ETSEST- (‘1st}U90 T) OL T688ET- 69FSSL- 9Z0801- F69660- G9TLLO- 66L190+ L6G9F0- 98060. GEPSTLO- 1n1Z *‘SUTWID PN HIOOr OO *SOUMULRAD ITIL ‘suImLy ‘of ‘suman opm “of ‘somupebyppge “wHDIT AA ("g) “panurzuo: Z99889- 1 96LELF+T O&60TS-T POOLFL-T ‘Sot PLELES-6 LIS&61 +8 6F9TSS 9 L86S16-% CCELLZ-S G998EI> T 96LELE-T OS60TS+T POOLFL-T ‘soaqt{100P FLGTES +6 TISS61-8 6FOFSS-9 L86S16-F CZELLZ:S. * Z99889-T 96LFELF-T OS60TS-T FOOLFL-T *g0.1}1[I}U0D FELOLE8-6 [LISS6L-8 6F9FSG-9 L86G16.F CCELLZ-S 299869 -1 *SOlgryy pe * 4 \ 6 8 L 9. G + & va Th , 2 ca “8F8ZE6- FS 006. 608028 SF 3 008 TELL CR SORE: BEZGI9-9E 009. $69GTS «08 00¢ COLOLF- 4% —00F- YI9L08+8L 00g LLOGOZ-3E_ 003 686201 -9 Crap, 13 oor C8CZ6F-S . es ORE. TS0Z88-F i 08 | LLLILG’P reOne: GZST99-S 09° 69ZIS0-S 2 =OG%: CLOIFE-S : OF ZOLOSS- TL. “oe OB: “80G0%G-L- 08 FS30T9- Cqyne9 D BI) os “8226S. , 65": GOZSSF. 3 QLILGPs wn Pe, = SCCTGOGs iat oy te eB SL PATROG «| are ¢ COTE oh Oe QUOGRY rh so ee Ras TSOCSL- Pi AES CZ0190+ — ! nue “suy"qno Sites ‘sur "qno| ‘of Ssouguuppy opm “OP ‘soyour a1qgng "KLIDVAYQ) ¢ @) I—SOINSBORY OJON PUB YStyIIg Jo WOISL9ATOD | Tahaan: 19 "nut D aie? ‘. BY ‘of ‘sayour ongng 07 sae ee c : IV. Refractive Indices, Dispersive _ Fahrenheit and Centigrade Powers, and Polarizing Scales. -- Angles. Cent, Cent, akoe (1.) Rerractive Inpiczs. oO ° ~~ 260° 0 100 212°0 232° 22 98 208°4 || Diamond — 204-44 96 204°8 =. 17667 | 94 re 448-89 92 197:6 || Bisulphide of carbon ~ 121-11 a 194°0 || Flint glass ~~ 100-0 8 190°4 "98-89 86 186-8 || Crown glass 96°11 84 - 183-2 || Rock salt 93°33 82 173°6 90:56 | 80 ooo 87°78 78 172-4 || Linseed oil (sp. gr. +932) o/,,80°0 76 168°8 || Oil of turpentine (sp. gr. *885) ~. 82°22 74. 165°2 Meghisl Pato ak (2 161°6 a 76° 67 70 158°0 ||} Sea water 80 73°89 68 154°4 A 71-11 | 66 08 Pee = 68°33 64 147-2 || Air (@at 0° C. 760 mm.) 65°56 62 143°6 62°78 60 140-0 60:0 58 136-4 (2.) DispERSIVE POWERS. 4 57°22 56 132°8 : n 54-44] 54 129° |} Diamond 5 51°67 52 125-6 || Phosphorus os » 48°89 50 122°0 : 7 46°11 48 118-4 ee of carbon > Ge 43°33 46 114°8 Int $1a8s8 Oo Ree 20°96 44 111-2 || Crown glass a 37°78 42 107°6 35-0 40. 104-0 Rock salt 2 82°22 38 100°4. || Canada balsam a) ee = ee . Linseed oil (sp. gr. +932) s 32 89°6 Oil of turpentine (sp. gr. *885) © 30 86°0 |; Alcohol ; = ae os : Sea water ae 24 75:2 || Pure water & ore 0 : 8 18 64°4 (3.) Ponarizine ANGLES, = 16 6023. 3 oe eet oe Diamond 8 -=10- “50:0 || Phosphorus . — oe oe 46°4 || Bisulphide of carbon aade 39-2 Flint glass - 35°6 || Crown glass. 520: Rock salt 94-8 || Canada balsam 21°2 || Linseed oil (sp .gr. +932) Tat fetal bel Ee: fe ; ee . Oil of turpentine (sp. gr. *886) 12. -10°4 || Alcohol - ie © “ois || Sea water 18 — 09°4 ||. Pure water 20 — 4:0 Air OBJEC- (10 ) V. Table of Magnifying Powers. EYE-PIECES. * * Powell and Lealand’s No. 2: = 7 ‘Ae ani Beck’s No. 2 ve Reis we -s'mago zg ; ; , respectiv’ ely 7x oad anid = more than the Aguas: given ‘in is columns f e + TIVES. Beck's 2, % Beck’s 1, Powell’s 2, Beck’s 4, Beck’s 6 | Powell’s 1, and Powell’s 3.| Ross’s C. | Beck’s 3. § Powell’s 4, Ross's B. | Powel { Ross’s A. & Ross’s B, Ross’s D. : nearly.* re ss Focau LENGTH. q | : S S 2 in [1b | lin 2 in 3 in. | yin, | yin =e: | Z Magniryinc Power 8 ay i eb Rene Coa jae eas * | 10 | 12k | 15-] 20 | 25 = AMPLIFICATION OF OBJECTIVES AND RYE-PIECE CBS . ; COMBINED. i ins. 5 2 |i 10 15 20 50 40 50 4. 23 122 | 183}. 25 37% 50 623 |. 8 Si} 162]. 25 F883 50 662 | 832] 2 5 25 | 374 50 75. 100 125 13 62 334 50 662 100 1335} 1662 1 10 50 75 100 150 200 250 | 122 62% | 932 125 1873 250 | 3123 3 133 662 100 1332 200 2662 3332 rs 15 75 1123 f 150 225 4 300 375 $ 20 100 150 }~ 200 300 400 500 4,| 25 125 1874 250 375 500 625 — zs 39 150. 225 300 450 600 750 | 9 3.| S344 1663 250 3332 500 6662 8332 | 2 40 4 200 300 400 600 800 1000. 2} 50 250 375 500 750 1000 f 1290 . a 60 300 450 600 900° # 1200 1500. 2} 70 350 525 700 1050 1400 | 1750 | 21 + 80 400 600 800 "1200 | 1600 2000 | 24 eae’ 90 450 675 900 1350 1800 4 ©2250 pi Re 100 500 750 1000 1500 2000 2500 |. pa 110 550 825 1100 . 1650 2200 2750 . tae 120 600 900 1200 1800 2400 3000. | 180. 650 975 1300 1950 } 2600 }| 3250 tz | 140 700 1050 1400 2100 2800 3900- : z;| 150 750 | 1125 1500 2250. 3000 3750 as 160 800 1200 1600. 2400 | 3200 | 4060: _ i F170 850 1275 1700 2550. | S400 4 4250 oe TBO. 900. # 1850 | 1800 "2700 f 8600" | 4500 3} 190 |} 950 | 1425 | 1900 2850. | 38800 | 4750 a; | 200 } 1000 | 1500 | 2000 3000 | 4000 | 5000 2 | 250 P1250 fF 1875 Ff. 2500 8750 | 5000 F625: ) 2; |800 | 1500 j 2250 | 3000 4500 1 6000 } 7500 3 g5|400 || 2000 | 3000 4000 6000. ¢ 8000. f 10000. gy | 500] 2500 | 38750 | 5000 | 7500 | 10000 | 12500 gy | 600 3000 4500 | 6000 9000 4 12000 15000. 800 4090 6000 at sae 2 Eine AON 20000 Ci} ~ Bomal Seopa Soci ees FOR 1888, At 8 P.M. ee Wednesday, JanuaRy .. .. .. «. « « 10 a FEBRUARY ... .. . 14 Annuat Meeting for Blection 5 Ofinees ‘and Council.) 5 WEAROH. oo S85 Sy" oe alaes ens i re es Re oa “ APRIEE Sac s OR ile ea eae eek M. 5 EAS ee ee oe ee Oe aoe e ; a PUNE Ek ee a ge ee ze . OCTOBER! oie eG genes ue LU ee See NOWEMBEH cy. 0s 2, ae ee a Bik aoe Deerings ee oan ae eS ae * So STANDARD SCREW. ne The Council have made arrangements for a ‘fatther supply of Gauges and Screw-tools for the “ Sooty * STANDARD Sorew for OssEorives. ‘The price of the set (consisting of Gauge and pair of Screw-tools) is 126. 6d. (post free 12s. 10d.). eee for sets should be made to the Assistant-Seerotary. : : ‘For an scplantion - ite ‘nfoided: use of the gauge, seo J ournal of the Society, 1 a? pp. 548-9. A a aeremtsl FOR THE JOURNAL. ae ‘M, Cuarnas BLENCOWE, of 76, Chakioaey Lane, wW. C.,, is the aubiovieed Agent =F Collector for oe Agoosints on behalf oe the Beets ( 12 ) CHARLES COPPOCK (LATE PARTNER WITH R. & J. BECK), 100, NEW BOND STREET, LONDON, W. OPTICIAN AND MANUFACTURER oF SCIENTIFIC INSTRUMENTS, - INCLUDING MICROSCOPES. ASTRONOMICAL AND OTHER TELESCOPES. STANDARD AND OTHER METEOROLOGICAL INSTRUMENTS. ; CLINICAL THERMOMETERS. OPERA AND FIELD GLASSES. SURVEYING, NAUTICAL, and DRAWING INSTRUMENTS, including ARTISTS’ MATERIALS. OPHTHALMIC INSTRUMENTS. SPECTACLES AND EYE-GLASSES. READING GLASSES. HAND MAGNIFIERS. . STEREOSCOPES. me POCKET AND CHARM COMPASSES, &c. N.B.—AGeENT FoR R. B. ToLLes, oF Boston, Mass., U.S.A. ‘3 W. H. BULLOCH, OF CHICAGO, ILLs., U.S.A. M. PRAZMOWSKI (Late HartNack & Prazmowski), PARIS. M. A. NACHET, PARIS, ano : JOINT AGENT FoR Dr. ZEIss, JENA. ne OCULISTS’ PRESCRIPTIONS RECEIVE PERSONAL ATTENTION, 100, NEW BOND STREET, LONDON, W. ee Se ae Sale ee, ee ee ~*~ Floscularia JOURN. R.MICR. SOC. SER.AL VOLA . Flos L ay c JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY. APRIL 1888. TRANSACTIONS OF THE SOCIETY. IV.—Five New Floscules ; with a Note on Prof. Leidy’s Genera of Acyclus and Dictyophora. By ©. T. Hupsoy, LL.D, FR.MS. (Read 14th March, 1883.) Puates III. anp IV. Unit quite lately there were only six known species of the genus Floscularia, viz. :—’. ornata Pallas, 1766; F. proboscidea Khren- berg, 1832; F. campanulata and F. cornuta Dobie, 1849; F. coronetta, Cubitt, 1869; F. cyclops Cubitt, 1871. To these have been added, during the last three years, no less than five other species, viz.:—F. trifoliwm Hudson, 1881; F. regalis Hudson, 1882; and F. ambigua, F. longicaudata, and F. Hood, which have not yet been described. Mr. Hood has also sent me from Dundee two specimens of what both he and I think is possibly another new species, called by Mr. Hood “the ringed Floscule,” but whose extremely short hairs and impoverished lobes made me fear that it might only be one of the old species in bad condition. As, however, Mr. Hood has promised to look out for it this summer, I think it better to leave it for the present undescribed. F. Hood. (Plate III. figs. 1, 2.) This beautiful and strange creature was sent to me by Mr. Hood on the 25th December last year. He had just found it in a ditch on Tent’s Muir in Fifeshire, along with PF. ambigua and Cicrstes pilula. It is the largest of all the rotifers, as adult specimens are quite 1-10th of an inch long from the top of the dorsal lobe to the extremity of the peduncle. Its great size and its possession (like F. trifoliwm) of only three lobes would make it sufficiently re- markable; but in addition to these peculiarities it has two extra- Ser. 2.—Vol. III. M 162 Transactions of the Socvrety. ordinary flexible processes, perched one on each side of the summit of the dorsal lobe. I cannot yet hazard a suggestion as to the function that these processes perform. No other species has anything in the least like them. They appear to be hollow, and to communicate with two sub-spherical spaces lying between the two surfaces of the dorsal lobe. Fine muscular threads pass down and across them, and the animal can contract and expand each independently of the other and throw them into all kinds of positions. ‘The upper end of each seems to be separated partly from the remainder by a constriction from which a muscular thread runs down to the base; but though I have tried many objectives and every kind of illumination, I have failed to see the slightest trace of setae in them. Besides, if these were two antenne, they would be in a unique position ; all other Floscules have their pair of setee-bearing antenne on their sides below the trochal disk, while the dorsal surface carries a solitary setigerous eminence on the medial line. Mr. Hood tells me that he has seen both a young and an adult specimen of F. Hoodi discharge through these processes granular matter which gathered round their free extremities, and which the creature got rid of with difficulty. Frequently when the animal is fully protruded from its case, one of the processes is invisible, having been permitted to collapse as it were on to the dorsal lobe. Then the upper end of the visible process may be seen to move so as to form almost a right ~ angle with the lower portion; or again, the whole of the one process will be slowly lowered on to the dorsal lobe while the other is gradually distended and raised. The thickened rim of the three lobes carries a double fringe of setee, set just as they are in F’. trifoliwm, the larger row stretching outwards and the smaller inwards; and I have on several occasions seen a rapid flicker run all along the smaller seta, not constant or regular enough to produce the phenomenon of “ rotation,” but still a very obvious motion of each separate seta. The gape of the mouth-funnel alters constantly, now opening in the characteristic way shown in the figure, plate III. fig. 2 (which is the ventral view) and then closing by means of its many muscular threads, so as to reduce the aperture to a mere slit, or even to shut it up in puckers. If the animal is so placed that the line of sight strikes the middle of the dorsal surface obliquely, it will be seen that a nearly transparent ridge or buttress runs up from either side of the body to the back of the dorsal lobe, ending at the base of the process. One of these is shown in the side view (plate III. fig. 1). Between these two ridges there is a deep hollow, bounded above by the dorsal lobe and below by the rounded surface of the body. At the lowest portion of this hollow, and Five New Floscules, &e. By Dr. Hudson. 163 close to the buttress ridges, are the two eyes. It requires a little eare and patience to get a sight of them, as they are of only a pale _ pink and are frequently obscured by other parts of the animal. It is easy to see the true rotatory organ which consists, as usual, of a ciliated horseshoe-shaped rim at the base of the mouth- funnel and on the ventral side of it, and which is continued in two long curved lines down the vestibule to the lips. The contractile vesicle is unusually large and plain, and in all the specimens which Ihave seen it contained a cluster of yellow globules, which appeared black by transmitted light. As Mr. Hood asked me to name this rotifer, I thought I could not do better than name it after himself, not only because its very shape suggested it, but also because it seemed only right that of the five very remarkable rotifers that Mr. Hood has discovered, at least one should bear his name. F. ambigua. (Plate IV. fig. 1.) F. ambigua was discovered by Mr. Hood on Sphagnum in a mossy pool on Tent’s Muir near Luchars in May 1881, and by Mr. Bolton in September 1881 near Birmingham. Since then Mr. Hood has found it in Loch Rea near Blairgowrie Perthshire, on a coarse species of Chara, along with Cicistes Janus. This is the least elegant of all the Floscules; it is broad and stumpy, and its trochal disk appears at first sight to have but three lobes. ‘There are however besides the three larger lobes two slightly raised setigerous eminences on either side. Like F. Hoodit it has two semi-transparent dorsal ridges running up from the body to the dorsal lobe. These indeed exist in some degree in all Floscules, but are unusually prominent in the two above-named species. Its body is generally thrown into coarse transverse folds at the lower extremity, so as to make quite a well-marked separation between itself and the foot, the latter appearing to possess but half the width of the body at the point where it joms it. At various points across the body, and especially round the base of the mouth-funnel, there are usually several thick corrugations obscuring the internal structure. The creature’s habits are curious, and have been so well described by Mr. Hood in a communication to myself, that I cannot do better than give his own words :— “This Floscule is not a beauty, but what it wants in grace it gains in interest, for it is most amusing to watch it feeding. As soon as it has fully expanded its large head, infusoria of various species may be observed to be drawn swiftly down the large cavity formed by the lobes. The inward-setting current thus formed by the cilia at the base of the cavity seems to be stronger in F. ambigua than M 2 164 Transactions of the Society. in the other Floscules, as large animalcules, such as Kolpoda, Paramecia, and even free-swimming rotifers will often fall victims to this big burly and voracious creature. It has an insatiable appetite: I have frequently seen the young of Cicistes pilula and CE. wmbella devoured by it, the young of the large rotifers making eyen less resistance than the infusoria. At first I thought that F. ambigua was wholly carnivorous, as I had seen it reject vegetable organisms, but I have since often seen it devour young Volvox globator. When once it has got a victim within its great mouth-funnel there is no possibility of its making its escape, although with a full stomach IF’, ambigua seems inclined to play with its prey as a cat would with a mouse, allowing it to swim about within the funnel and to try to escape over the margin. Whenever the animalcule approaches the setigerous rim a sharp stroke from one or more sete drives it back into the funnel. I have seen the attempt to escape repeated again and again, but always with the same result; in no single instance have I ever witnessed the escape of a captive. No one would credit the voracity of this Floscule who had not watched it. I have seen one eat in half-an-hour no less than twenty-four live infusoria of various sizes ; it only gets a rotifer or a young Volvox now and then as a change of diet. F'. ambigua is by no means a delicate rotifer, for it can be kept in a live-trough in good health with very little trouble during the whole period of its life by merely furnishing it with a few drops of water from an aquarium daily. It deposits from two to five female eggs, which take about six or seven days to hatch. The young female when hatched is furnished vith very delicate vibratile cilia on the head, and with two red eye-spots. The frontal lobes are entirely absent. Pro- pelled by the frontal wreath of cilia the young Floscule swims rapidly and gracefully through the water for about two or three hours, poking into corners and crannies in quest of a fitting place of abode. : It selects for its future residence either the axil of the plant or the concave side of a leaf. It seems to prefer an ambush to an exposed spot, for I have never met with it on the point of a leaf. The young Floscule when first fixed on the leaf is so like a young Stentor that it might easily be mistaken for one; but in a short time a collar begins to develope immediately under the wreath of frontal cilia; and, as it rises above the wreath, the lobes develope from the collar, increasing in size as the animal grows. If fed well, the young animal arrives at maturity about the twenty-fourth or twenty-fifth day, and will then deposit eggs, but it never ceases to increase in size till shortly before its death. Its whole lifetime in a Five New Floscules, &c. By Dr. Hudson. 165 trough, if carefully attended to, is from forty to forty-six days, but of course if may live longer in its natural habitat. When old age arrives it does not contract its lobes closely if alarmed, and it is slow in expanding them or in contracting its peduncle. At last it ceases either to close the lobes or contract the peduncle, its setz fall off, the internal organs cease to move, and it dies with the lobes fully expanded. In two hours after death it is surrounded by swarms of infusoria, and in a few hours more these leave not a vestige of it, the Floscule haying in its turn been devoured by the very prey on which it used to feed. I had the good fortune to witness the hatching of two males of F. ambigua—they were produced ag usual from smaller and rounder eggs than those of the females. The digestive organs and mastax were wanting, and the anterior portion of the body was transparent, bearing a wreath of long vibratile cilia and two red eye-spots; the posterior portion contained the sperm-sac, with a tube leading towards the foot. It is a most restless creature, so that it is difficult to get a good observation of all its parts. F. longicaudata. . (Plate IV. fig. 2.) F’. longicaudata was discovered by Mr. Hood in a pool on Tent’s Muir in May 1881, and in Loch Rea in July and August of the same year. Although a rather rare rotifer, it is more social than F, ambigua, forming small colonies of half-a-dozen individuals or more. It differs also from Ff. ambigua in its choice of habitat, for it prefers to perch itself on the exposed end of a leaf; whereas F’. ambigua forms its tube in the axils of the plant itis on, or on the concave side of the leaf. ‘The creature’s chief peculiarity is the very long non-retractile peduncle in which the foot ends. This peduncle exists in all Floscules, but is usually not more than 1-15th or 1-20th of the length of the foot; in F. longicaudata, however, the peduncle is often 1-3rd of the length of the foot. It is a thin transparent thread, and is frequently thrown into graceful curves and coils. The lobes of the mouth-funnel are usually more angular than those of any Floscule I am acquainted with ; the specimen from which the figure was drawn showed this pecu- larity ina marked way. The dorsal lobe is as usual the largest ; and the two ventral lobes are larger than the two side ones, which indeed are at times quite insignificant, though their presence is always indicated by the pencils of radiating sete. All the specimens which Mr. Hood sent me had neater and more compact tubes than those of other species; but, as they also differed considerably from each other, this may have been accidental. 166 Transactions of the Society. F. regalis. (Plate IV. fig. 3.) Mr. Bolton sent me this remarkable rotifer last September. Its trochal disk is quite unique, for hitherto all the known species of Floscules have had either five or three setigerous lobes. It is true that Ehrenberg credits his I’. proboscidea with six lobes and a flexible open-mouthed tube rising from the midst of them, all crowned with sete, and says that he has found F. ornata sometimes with five lobes and sometimes with six ; but hardly any other observer has seen a six-lobed Floscule. Mr. Slack, in ‘ Marvels of Pond Life,’ says that he has met with F. ornata bearing six lobes, with “six hollow fan-shaped tufts [of sete], one attached to each lobe.” Dr. Dobie also states that a friend of his, viz. Mr. Hallett of the Museum of the Royal College of Surgeons, had found F’. ornata “ with a six-lobed rotatory organ.” Such precise statements ought perhaps to settle the question; but Mr. Slack goes on to say that “for a long evening only five could be discerned in the specimen now described, but the next night six were apparent without difficulty or doubt,” and he attributes the discrepancy to the different positions which the Floscule held. It is quite possible then that Mr. Slack had F. regalis under observation, and not F’. ornata, and that the creature’s varying positions hid now one, now both, of the smaller lobes. Ehrenberg’s F. proboscidea may have been also the same creature; for though Ehrenberg describes it as having a flexible snout-like tube with an open mouth rising in the midst of the lobes, his figure shows merely a well-developed dorsal lobe with a clear space near the summit between its two surfaces. This clear sub-spherical space exists in several species of Floscule, and Ehrenberg seems to have mistaken it for the mouth of his “flexible tube.” His figure bears rather the broadly-curved lobes of F’. cam- panulata than the knobbed ones of F, regalis, but he distinctly says that the lobes were knobbed. Possibly there may yet be another species of seven-lobed Floscule with flattened lobes; at any rate, I think it not unlikely that Ehrenberg had some seven-lobed Floscule when he described F. proboscidea. The mouth-funnel of F. regalis is a deep cup with a nearly circular rim, from which project four knobbed processes on the ventral side, dividing that half of the rim into three equal spaces. They curve slightly outwards and widen as they approach the rim, so that their bases unite, and give to the edge of the cup a hexagonal appearance. On the dorsal surface rises a large triangular knobbed lobe bearing on each side of its base two very short recurved knobbed processes. All the seven knobs carry pencils of long radiating sete. Five New Floscules, dc. By Dr. Hudson. 167 It is worthy of remark that Cubitt’s F. coronetta carries two small pencils of radiating setze near the base of the dorsal lobe. In the specimens that I have seen it was easy to make out both the eyes and horseshoe-shaped row of vibratile cilia at the mouth-funnel. None of the specimens exceeded 1-50th of an inch in length. The ten (or eleven) species of the genus Floscularia may be arranged as follows :— * Lobes without knobs. Not separated by { Two processes on dorsallobe F. Hoodii. With 3 large iaios minute ones... | No processes co oe 00 IEE tayo Separated by two minute ones .. .. ., .. F. ambigua. Lobes broad, de-{Peduncle short .. .. .. F. campanulata. With 5 lobes { pressions distinct { Peduncle very long .. .. JF. longicaudata. Lobes round and small, depressions indistinct .. 2. Cyclops. ** Lobes knobbed. Flexible process on dorsal Lobes triangular WOIaS) ee 60 do ae ce PL Galmiiaey With 5 lobes INOprocess <2 =. ce) ee HL onnatas ROP OMEO AER OEE . LF. coronetta. Lobes linear .. With 7 lobes . F. regalis. and perhaps F., proboscidea. I find that I have omitted to mention that Mr. Hood found on one or two occasions a Floscule inhabiting a trumpet-shaped tube, and that he thinks this also isa true species new toscience. I have not had the good fortune to see the rotifer, as it died in the transit, but I have great hope that neither this species nor “ the Ringed Floscule ” will escape Mr. Hood’s energetic search and keen sight during the coming summer. Note on Prof. Leidy’s genera of Acyclus and Dictyophora. Professor Joseph Leidy has lately discovered and described * a very curious new rotifer, which ought, I think, to be placed near the Floscules. He says, “ While examining some Plumatella diffusa from the Schuylkill river below Fairmount Dam my attention was attracted to several groups of Megalotrocha alba attached to the tubes of the former, and surrounding another animal of strange and novel character. This, on examination, proved to be a remarkable rotifer without rotary organs. . . . This new rotifer I propose to name Acyclus inqwietus (fig. 31), from its being destitute of wheels or ciliated disks, and from its apparently restless habit. It is con- siderably larger than Megalotrocha, measures nearly a half line long, and can be readily distinguished in groups of the latter with * Proc. Acad. Nat. Sci. Philad., 1882, pp. 243-50 (1 pl.). 168 Transactions of the Soctety. the naked eye. It was observed in eight instances, in each alone, and always inclosed in a group of Megalotrocha, above which, from its greater size, it towered like a giant in a crowd. . . . Acyclus is translucent whitish, with the thicker part of the body yellowish or brownish, due to the colour of the capacious intestine shining through the integument. It was difficult to obtain a clear and accurate view of the exact mode of attachment and the internal structure of the animal, from its Fig. 31, Fic. 32. incessant motions, its becoming (=) wrinkled in contraction, and from its being obscured by the surrounding bunch of Megalo- n trocha. . . . The head is in the { form of a cup prolonged at the Head. mouth into an incurved beak. It is retractile, protrusile, con- \. tractile, and expansile. When pro- truded and expanded the mouth gapes ) = os widely, and the beak becomes more ex- tended, but always remains incurved, The mouth is bordered by a delicate membrane extending to the rounded end of the beak, and presenting a festooned appearance. . . . In contraction of the head or oral cup it is reduced to half the bulk of its expanded condition, while the mouth is constricted and the beak is rolled in a single spiral inwardly, as seen in fig. 832. The extension of the head below forms a narrowed and transversely eR, Se eee wrinkled neck, which expands into the Acyclus inquietus. body. The expansion and contraction Entire animal. of the head appear to be due to the flow of a milky liquid between the ccelum or body-cavity and intervals in the walls of the oral cup or head. The retraction of the latter is produced by longitudinal muscles, which may be seen in the wall of the cup extending from the wall of the body just below the neck to the festooned membrane bordering the mouth . . . The oral cavity converges in a funnel- like manner to a pouch occupying the neck. The pouch is seen to contract and expand from time to time, but it was indistinctly defined. At the bottom of the pouch there is a small mastax, or muscular pharynx, provided with minute jaws.” Professor Leidy goes on to say that the jaws have a parallel series of about twenty teeth, that the tail is occupied with retractor muscles extending from the walls of the body, that the interval between the stomach Five New Floscules, dc. By Dr. Hudson. 169 and wall of the body is occupied by the ovaries and ova, and that in the vicinity of the lower extremity of the stomach there were several yellow spherical balls. Most of the individuals observed were without a case, but in two instances the animal was included in a “copious colourless gelatinous sheath,” and had also adherent a large bunch of eggs, in one of which were as many as fifty. It is clear from this description that Acyclus inqwietus re- sembles the Floscules in many respects. Its “oral cup” with the “imeurved beak” may be fairly said to be the buccal funnel of a Floscule reduced to the possession of one lobe, viz. the dorsal one. The “oral pouch” in the wrinkled neck is the counterpart of “ the vestibule” of the Floscules, just above which, and generally hidden by the wrinkles, lies the true rotatory organ, and at the base of which is the true mouth. In both genera there are minute jaws just below the vestibule ; in both the buccal funnel is retracted by longitudinal muscles, which take their origin in its outer rim, spread over its wall, and pass down the body right to the end of the peduncle; and in both the buceal funnel is expanded by means of a fluid driven into spaces between the cuticle and dermis. To complete the points of resemblance Acyclus is attached when adult, and is occasionally surrounded by a gelatinous sheath, in which lie the extruded eggs. The main differences are the entire absence of setze from the rim of the buccal funnel, the apparent lack of any vibratile cilia, the edging of the buccal funnel with a delicate membrane, and the presence of about twenty parallel teeth in the jaws. The first of these differences is not one of much importance, for the length of the sete differs remarkably in the various species of Floscules. In some—as in F’. ornata and F. campanulata—they extend to quite the length of the animal’s body, while in F’. Hooda they are hardly half the width of the buccal funnel; and Mr. Hood thinks he has seen on several occasions a new species in which they are shorter still. The membranous edge of the buccal funnel and the numerous teeth in the jaws clearly mark off Acyclus from F'los- cularia, but the still more striking difference, viz. the absence of a rotatory organ, may, I think, be only an apparent one. As I have already remarked, this organ consists of a ciliated horseshoe-shaped ridge on the ventral side of the buccal funnel, just where it joins the vestibule, and it is in some species continued down the vestibule in two lines towards the mouth. In most of the species it can only be seen in some fortunate position of an unusually transparent specimen ; but in F’. trifoliwm and F. Hoodii it is quite easy to make it out. Now, considering the difficult circumstances under which Professor Leidy saw Acyclus, its restless habits, and its thickly-wrinkled cuticle, it is not impos- - sible that this rotatory organ may have been overlooked. 170 Transactions of the Society. That however does not seem probable in the case of another very strange rotifer, described and figured by Prof. Leidy in the same paper, and which he discovered and described in 1857, giving it the name of Dictyophora. As the animal is attached by a sucking disk, is almost motionless, very transparent, and free from wrinkles, the rotatory organ would not have escaped notice had it been present; yet neither Prof. Leidy nor Mr. S. A. Forbes, who probably described the same creature under the name of Cupelopagus bucinedazx,* could detect any vibratile cilia. Prof. Leidy says that “Dictyophora is oval or ovoid, with the narrower pole corresponding with the position of the mouth, truncated, and it adheres by a small disk or sucker to one side of the broader pole. . . From the truncated extremity of the body the animal projects a capacious delicate membranous cup, forming more than half a sphere, and more than half the size of the body. At will the cup is entirely withdrawn into the body, and the orifice of this becomes contracted and puckered into folds radiating from a central point or orifice. . . The prehensile cup opens into a capacious sac, which is within the body and occupies a good portion of its upper half. The sac at bottom communicates with a mastax nearly central in position. . . The mastax opens into a capacious sacculated stomach. . . Numerous ova in all conditions, from the earliest to those which contain fully developed embryos, occupy the body-cavity of Dictyophora, sometimes in such numbers as to obscure everything else from view.” This most curious animal still retains some likeness to the Floscules in spite of the degradation of so many parts. The “membranous edging” of Acyclus has here developed at the expense of the buccal funnel, which it has entirely supplanted, and the peduncle has shrunk down to a mere sucking disk; but the “capacious sac,” which lies between the mouth and the mastax, is the exact counterpart of a Floscule’s “crop” in which its food accumulates after slipping down the tube hanging from the mouth, and before passing the mastax into the stomach. On the other hand the mastax with its five teeth in each jaw, and also indeed the position of the sucking disk (which is on the side of the ventral surface towards its lower end instead of at its extremity) are decided points of difference, to say nothing of the complete absence of buccal funnel, lobes, setae, and vibratile cilia. Prof. Leidy quotes Cohn’s remark that a rotifer without a rotatory organ would be a “rude abnormity” (eine schroffe Abnormuitdt) ; and indeed it does seem at first sight a very nice question whether an animal that has no rotatory apparatus can be a rotifer. Yet Stephanoceros and all the Floscules are pretty nearly in this condition; for their generally motionless sete have * See this Journal, ii. (1882) p. 625. Five New Floscules, dc. By Dr. Hudson. 171 no sort of pretension to be considered as forming a rotatory organ, and their vibratile cilia are so few and inconspicuous that their loss alone would not be reason enough for removing these two genera from among the rotifers. It is among the Notommata and their allies that we find the most numerous instances of the degra- dation of the trochal disk, especially among the parasitic species ; and this, as might be expected, is often accompanied by the degradation or loss of other characteristic organs, until at length in Gosse’s Taphrocampa we arrive at a larva-like creature destitute alike of gastric glands, vibratile tags, contractile vesicle, and trochal disk; its sole connection with the Rotifera being its characteristic mastax. Prof. Leidy suggests that perhaps Taphrocampa may have a rotatory apparatus, which was concealed when Gosse observed it, just as it was in the case of Lindia torulosa when Dujardin discovered it. This of course is possible; but even the possession of such ciliated appendages as those of Lindia would leave Taphrocampa stripped of the greater part of a rotifer’s characteristics. In passing under review such a series of creatures as Lindia torulosa, Albertia vermiculus, Notommata Werneckii, Balatro calvus, Seison Gruber, and Taphrocampa annulosa, it naturally occurs to one that, in the case of animals departing so widely in other respects from the rotiferous type, the further loss of a few vibratile cilia would not seriously affect their classification; but if Cohn - merely meant that it would be a “rude abnormity ” for a rotifer to possess all the chief characteristics of its class, the mastax, vibratile tags, contractile vesicle, &c., and yet lack a trochal disk, he is certainly right; for no such rotifer is as yet known. But Prof. Leidy’s interesting discoveries make us acquainted with at _least two genera that are perilously near such an abnormal state of things: for, although no mention is made of the contractile vesicle and vibratile tags of Acyclus and Dictyophora, it is obvious that they may exist, as it would be at all times a very difficult thing to see them. 172 Transactions of the Society. V.—The President's Address. By Prof. P. Martin Duncan, M.B. Lond., F.R.S. (Annual Meeting, 14th February, 1883.) Every Fellow of this Society who has attended the evening meetings during the last twelve months, must have been struck with the very practical nature of our proceedings, and that the observations made, and the apparatus exhibited and described on those occasions, indicated a growing desire for the perfection of the Microscope. At the same time it must have been evident that the application of the instrument to its proper purposes is open to many sources of error, and that there is an amount of intelligence and knowledge required in the management of the Microscope, which is the result of much labour, thought, and experience. Common sense might tell everybody this, but it sometimes happens that when a man has invested a certain number of guineas in an instrument, he imagines he is correspondingly endowed with the abilities of a microscopist in the true sense of the term. On the other hand a very large number of able men become possessed of instruments humble in appearance and not costly in any sense, and they rest satisfied that a Microscope is a Microscope, and believe therefore that they see the true invariably. One of the benefits of belonging to our Society is the opportunity of seeing objects properly shown by the ablest manipulators, and of hearing com- munications on the imperfections and corrections of the instrument, and it would be well if our list, full as it is, were crowded by those scientific men who constantly use the Microscope in original re- search in biology. A considerable experience impresses me that the majority of students, and not a few professors, not only use indifferent instruments, but also carefully avoid all those practices which we know are absolutely necessary for correct microscopy. A thing is seen, therefore it must be real; one man sees a spiral line, another a circle, another a series of dots, using the same object and different Microscopes. They describe and debate and each is self-satisfied. Yet all the while had they had a master in microscopy, their differences could be terminated. We constantly read of wonderful researches involving great dexterity of preparation, tedious dissection, and elaborate mounting, consummated at last by a description of what is seen under a Microscope. Some one else follows the subject and cannot see what the previous observer has drawn. Here the difference clearly relates to the Microscope, and therefore it is worth while to pass in review and remark upon some of the results of the work of our Society during the {past year, so that workers may be stimulated The Presidents Address. By Prof. P. Martin Duncan. 173 to care more for the instrument than most of them have done hitherto. Most of the inexperienced, and not a few experienced Microscope- possessors illuminate, when transmitted light is used, in a manner exactly opposite to that which they follow with the unaided eye. They get all the light possible from a reflecting surface. Common experience teaches us that there is an exact relation between the possibility of seeing the half and lower tints and of searching the depths of shadows, and the intensity of the light entering the eye. It tells us that only outlines are well shown as sky lines, or when a brilliant light is passed around and through the body examined. Yet a pleasant evening with the Microscope generally means a painful time for the eye. A good glare of light, thanks to lamp, condenser, mirror, and forgotten diaphragm, appears to be almost invariably a desideratum to the beginner. Experiences teaches, however, and the advanced microscopist never uses more light than is absolutely necessary, and increases and diminishes the illumina- tion during the careful observation of an object, not only by employing a less intense source of light, but also by using diaphragms of different sizes. The employment of different tints of coloured light, especially pale blue and green, gives a wonderful relief to the eye when transmitted light is used with or without a dark black ground. In examining siliceous organisms the relief is great; but practice follows theory in rejecting purples and allied tints, the more delicate shades of which are not readily distinguished by the eye. One of our Fellows has lately introduced a very simple apparatus which enables a succession of colours or a group of tints to be used, and there is no doubt that it will be much valued. The method of application of the electric light to the Micro- scope, and the beautiful apparatus which has been exhibited before the Society, must have impressed everybody that it will be the light of the future. The brilliancy and coolness of the light, and the possibility of directing it readily in investigating opaque objects with low and very high powers, commend the method of illumina- tion. It will be of great use in investigating objects by means of high powers with reflectors within objectives, and in moving around opaque objects which are well in focus under low powers, and whose surfaces are difficult to define under ordinary circumstances in a short time and with the usual appliances. We may expect that on all occasions when there is an exhibition of a considerable number of Microscopes, the electric light will be used, and the dangerous and offensive rock-oils abolished. Since microscopy has been extended to the examination of sections of rocks composed of different minerals, the truth that Some can be roughly distinguished by their dichroism under the 174 Transactions of the Society. polarizing ray, the analyser not being used, has become apparent. The polarizer is also useful in another manner. [Researches have been undertaken to examine into the influence of the polarizing ray upon substances which may or may not give the usual phenomena under the analyser. Polarized light carefully manipu- lated is very useful in examining thin sections of corals which are made up of closely placed fusiform and long alternating prisms, with geometrical prisms of carbonate of lime in planes one over the other, and often radiating from different points. Shadow and high light succeed when the Nicol is rotated, and minute details become apparent which are not seen, or are only feebly defined, by ordinary light reduced in its intensity to that of the polarizing ray by the use of diaphragms. Some time since, in investigating the structure of a fossil which was composed of close radiating and occasionally inosculating tubes with very thin walls and a distinct lumen, all mineralized with calcite in the glassy, non-crystalline form commonly seen in fossils where there is much space unoccupied by structure, the polarizing ray certainly made the tubes more distinct than the ray reflected from the mirror alone, and by rotating the substage Nicol, the position of certain tubes which were invisible before could be ascertained; that is to say, dark lines appeared limiting tubes which were invisible under ordinary illumination. The application of the whole polarizing apparatus is very useful in working at the minute superficial structures made up of thin and highly refractive plates of organic carbonate of lime. The glare of light under ordinary illumination and even when the polarizer only is used, prevents the true surface being focussed, or if if is fortunately hit upon, it is more or less invisible. But the analyser being placed across the direction of the polarizing ray the true surface can be found by the definition and distinctness of the clear colours and the intermediate lines. Take away the analyser, and often new structures appear to the eye. Asa matter of practice I find that this method is exceedingly useful. Many a possessor of a valuable instrument has been discouraged at the outset of his work by the want of definition of his high powers and by the presence of glare in his field, and even of a spot where nothing is visible. He has everything at his command in the way of the instrument, or nearly so. But he works in a room full of diffused light, and probably uses no diaphragm or cap to his elaborate condenser. He suffers from reflection in many directions. One of the simplest troubles of the young worker arises from his not preventing the access of light upon his object when he is working by transmitted light, and the failure when employing high objectives relates to similar causes and requires similarly simple remedies. The President's Address. By Prof. P. Martin Duncan. 175 There certainly is a cause of error latent in many mirrors, and many Microscopes of the small type have their reflectors so made as to reflect light quite as much from the brass edge as from the glass. Carefully examined they are found to be badly silvered, and the result is unequal light. There is no doubt that many of our best practical microscopists use direct light whenever they can ; and it is equally true that mirrors and their reflected light are often very difficult to manage. Perhaps the re-introduction of plane silver mirrors will relieve workers from some trouble. Ii ig almost a presumption to remind those whom I have th honour to address that there is no gain by amplifying at the expense of definition, and that the short eye-piece with its high power searches out and makes the errors of the objective manifest. But it may be asserted that comparatively few microscopists select that eye-piece which produces the best results in combination with a given objective. The medium eye-piece is almost invariably used. Now there is, as we hope to hear clearly demonstrated shortly by Professor Abbe, a necessity for balancing the performance of the Microscope between the objective and eye-piece, in a manner which is not simply empirical. There ought to be (the length of the tube of the Microscope being invariable) a positive relation between the performances of the upper and lower system of lenses, and therefore between the magnifying power of the eye-piece and the numerical aperture and amplification of the objective. Experience proves that it is not the longest eye-piece or a regulation medium one which will always produce the best results with a given objective, and that it by no means follows that the eye-pieces supplied with a Microscope will suit the objectives which may be added from time to time, or even those originally put up with it. Without carrying this subject further I might state that in my own case a medium and a long eye-piece of excellent workmanship, and which usually give excellent results, do not evolve the qualities of a Zeiss objective (EK) which is of a moderate numerical aperture, so well as one of slightly higher power and shorter tube than the medium one just noticed. But this eye-piece does not do the same Service when a Gundlach water-immersion (1-12th in. focus) is used, and the longest eye-piece then answers, although the objective was made for the length of tube generally used in this country. Circumstances have brought me in contact with cheap Micro- scopes, and certainly whilst it may be said that some of the objectives are fairly good, the eye-pieces are on the miserable “par” with the rest of the apparatus. I cannot avoid believing that during the next few years attention will be paid to increasing the merits and adaptability of eye-pieces whatever may be their special character. 176 Transactions of the Society. It is pleasant in these days of free thought to have the mind, which has got rather into the “rest and be thankful” mood, suddenly awakened by the jarring sound of such assertions as those made with regard to the binocular Microscope by Professor R. Hitchcock. “The stereoscopic effects, while not of great practical importance, as already stated, certainly render many objects more attractive to look at. For this reason a Microscope for the entertainment and instruction of friends should certainly be a binocular.” * The Professor states that there is no advantage in a binocular Microscope in studying the form of objects, but the value of this opinion is shaken when he asserts, in the same sentence, that the appearance of relief the binocular gives is not necessary to enable us to form a correct idea of the true state of objects in which the appearance of relief is most striking. He qualifies his opinion, however, by writing :—“It is true that the binocular does reveal more of the form of an object at the first glance than the monocular, but it is a matter of experience that those who only use one eye in microscopical work, never make the mistake of supposing that an object is merely flat because it seems to be so. A few turns of the focussing screw soon give a correct idea.” The Professor considers that the value of the binocular is restricted to the comforts of vision. I do not think that these views will receive acceptation in the old world; on the contrary, it is to be hoped that the late admirable adaptation of an objective of high power by a distinguished Fellow of this Society to the binocular will pave the way to still more advantageous developments of the binocular system. Constantly using objectives of low power in examining objects of natural history, naturalists find that the binocular enables them to decide at once whether a series of markings are elevations or depressions or alternate elevations and depressions. With the monocular they must shift the illuminating beam as well as alter the focus, so that they can see the truth, revealed at once, by the other instrument. In the address which I had the honour of delivering to you last year I remarked upon the comparative values of object-glasses with high and low numerical apertures, and I took pains to defend the employment of lenses with wide apertures in examining minute objects, and also to state that both kinds of objectives are necessary for investigating into the structure of minute objects. I suggested what has commended itself to every advanced microscopist for years past, that an observer should provide himself with both classes of objectives, and that he should use those with a moderate aperture for common and preparatory work, and those with a high numerical aperture for subsequent and careful examination. * Amer. Mon. Micr. Journ., iii. (1882) p. 417. The President's Address. By Prof. P. Martin Duncan. 177 Subsequently Professor Abbe sent a communication to our Journal which pretty well sets at rest the former debates about the value of objectives with a high numerical aperture, and thoroughly defines the relative value of the two classes of lenses. He states “the obvious inference . . . is that the widest possible apertures must be used for the observation of objects or structures of very minute dimensions, low and moderate apertures for relatively large objects.” The ordinary microscopical investigation of the structures of animals and plants can be best done with lenses of low numerical aperture. But when minute structures require to be accurately defined there must be a wide aperture and also a corresponding amplifying power. Deficiency of power renders a high numerical aperture useless, and therefore wide apertures are necessary when a high amplification is required. Professor Abbe’s conclusion regarding the practical value of the two classes of objectives is quite consonant with the opinions which have often been expressed at the meetings of the Society: ‘“ Wide apertures (together with high powers) for those preparations only, which do not require per- ceptible depth of vision, i.e. for exceedingly flat or thin objects, and for transparent objects which can be studied by optical sections. Moderate and low apertures when a wide range of penetration cannot be dispensed with.” With great wisdom Professor Abbe explains the positive damage connected with the use of unnecessarily wide apertures and notices that increase of aperture may be prejudicial to the ease and con- venience of microscopical work. It necessitates a progressive reduction of the working distance of the objective, and this is still further diminished during the necessary correction, for increase of aperture is inseparable from a rapid increase of sensibility of the objectives for slight deviations from the conditions of perfect correc- tion. He impresses upon microscopists that the best wide-angled system, if not carefully adjusted when in use, is not better than a bad low-angled lens ; for the tolerably sharp image which could be still obtained through the central part of the aperture only (even under the imperfect state of correction) is disturbed by the coarse dissipation of light from the ineffective marginal parts of the aperture. Dividing microscopists into those who amuse themselves and those who work, Professor Abbe advises the latter never to use wider apertures than are necessary for the effectiveness of the power, because excess of aperture always involves waste of time and labour. It has always seemed an anomaly that when a good objective with a high numerical aperture has been obtained, many operators have diaphragms or stops added. The object of so doing is evident, but the practical difficulty arising from the small working distance is not removed. Moreover, there is a reason- able doubt whether an objective thus treated is really as effective as Ser. 2.—Vo1. ITI. N 178 Transactions of the Society. one of a lower numerical aperture and of the same amplification. Professor Abbe writes, in reference to stops and diaphragms in relation to high numerical apertured lenses, “The greater penetra- tion and insensibility of the low apertures may of course be attained thereby, but nevertheless this device is only a makeshift, and the result is inferior to that obtained by objectives originally arranged for a lower aperture. The low-angled lens which is made out of a good wide-angled one by means of a stop, is, in optical respects, a relatively bad objective—not nearly as well corrected as the same power would be if carefully adjusted for the lower angle.” There can be no doubt that microscopists will require most carefully made objectives with a low numerical aperture as much as ever, and no wise man will confine himself to nothing else in the way of ob- jectives than those of high numerical apertures, whatever may be the amplification. Clinching the argument, Professor Abbe con- cludes his essay with the remark, “Scientific work with the Microscope will always require not only high-power objectives of the widest attainable apertures, but also carefully finished lower powers of small and very moderate apertures.” One of the difficulties met with in the adjustment of objectives for correcting the aberration involved by the presence of a thin glass cover and a medium over the object, is caused by the awkward position and direction of movement of the screw-collar. A careful microscopist will of course keep the screw sufficiently easily move- able for his purpose, but unless this is done, the attempt to unscrew or screw up is often accompanied by drawing the objective out of the desired line of sight, and even by unscrewing it at the junction with the tube. In fact it is perfectly obvious to those who have the opportunity of working with other observers, that accidents readily happen to the object during the process of correction. ' These troubles have been noticed in every manual on microscopy. It appears, however, that the worm-wheel and tangent screw, suggested by Mr. J. Deby, when its application is made a little easier, will meet all difficulties, and it may be added to a screw- collar which could be used without the improvement in those rare instances when a rapid movement is required. Very few microscopists care to correct their objectives during ordinary work, and principally because they have not seen the difference made in the appearance of an object by the process when it has been carefully carried out. But when an object, hitherto unsatisfactorily defined, presents itself under a clear and definite aspect, conversion to the opinion that there is an absolute necessity for correction in all delicate investigations regarding minute structures speedily ensues. There is no doubt that with very few exceptions the microscopic work relating to the morphology of the animal and vegetable kingdom has been conducted either without - The President's Address. By Prof. P. Martin Duncan. 179 corrected objectives or with those which have an average adjust- ment. I pointed out in my last address how abnormally thick, slender and excessively minute bodies appear under a high ampli- fication ; this is partly due to a want of correction, and mainly to another cause which it is not necessary to revert to. Now I have no hesitation in saying that similar abnormalities are constantly recorded as truths, and for that same reason which causes excellent observers to differ in a most remarkable manner about the appear- ances of the same object under different Microscopes. Many microscopists do not know how to use the screw-collar, and I have taken the pains to inquire of several workers how they proceed to correct. A very general answer is, I focus the dirt on the top of the thin glass and then screw down until the object is in focus. So that this mistaken correction produces a double amount of error. No one doubts the necessity for correcting dry and water- immersion objectives, or that it ig very much less in the case of homogeneous-immersion systems, but in spite of Dr. Dippel’s lively assertions to the contrary, practice has shown that an object whose true shape has been learned has been seen all the better after correction for the index of refraction of the thin glass cover with a medium above it and one below. Doubtless this refraction is minimized by the homogeneous- immersion system, but even then there is the variable refractive index of the thin glass cover to be considered. For perfect work, correction is necessary in the instance of the oil-immersion objectives. Unfortunately the method of correcting, or rather the amount of approach of the front and back set of lenses of the objective which is required, has to be estimated empirically. Hither the - front lens and back pair are to be placed at a medium distance, and when the objective 1s focussed on the object this distance must be diminished or increased until what is believed to be the true shape of the object is seen; or what has the greater rudiments of exactitude in it, the focus having been taken with the lenses sufficiently distant for uncovered objects, the collar is worked to the left until the top of the thin glass is seen. Then the object is refocussed. ‘This last plan would be the best were it not a fact that a source of error is revealed by the increase of amplification during the correction. The method of Mr. Wenham, by which the hinder pair of lenses is pushed forward towards the stationary distal lens, in correcting for cover, is vastly superior to the old plan of moving the front lens. What exact relation there should be between the distance of the front and back series of lenses in the objective, and the thickness of the thin glass cover over the object, and that of the medium between N 2 180 Transactions of the Society. the object and the cover, must depend upon the refractive indices of the thin glass and medium, upon the aggregate of refraction due to their thickness, and the numerical aperture of the objective. Practically the relation is considered to be exact, and the distance between the objective series is made to equal the vertical distance between the top of the thin glass and the surface of the object during the process of correction. My impression, however, is that the distances are not equal in fact, and that that between the objective series is less than the vertical amount between the object _ and the top of the glass when a proper correction has been made. It. has been put very forcibly by Dr. Dippel that if the shape of the object is unknown, correction may be a mistake, and that when the focus is at a lower plane than the summit of the object, correction may positively mislead. There is no doubt that an image seen under a certain correction, and which is stated to be normal, is modified by under- and over- correction. How to get at the truth is difficult, except in the instance of geometrical bodies and definitely parted lines, but the examination of the same object by many observers with different instruments gives experience, and without indulging in calculations, including the method of least squares, it is finally settled that such and such is the real shape. The possibility of error remains, however, and it is perfectly evident that many a difference of delineation of carefully investigated objects results from non-correction and over- and under-correction. One cannot but help thinking that the difficulties in correcting dry objectives of high amplifying power and great numerical aperture, will lead to the almost constant employment of immersion objectives. And really the only researches which are rendered more difficult by the immersion principle, are those which have rendered the name of Dr. Dallinger so illustrious. There is no doubt that it is impossible to prevent the admixture of the medium with the water below the thin cover when minute organisms are followed here and there and often close up to the edge of the glass cover. Amongst the results of not correcting objectives are want of definition, haziness, and the production of certain colours, and this last phenomenon is often observed in objectives which are corrected up to a certain degree and fixed. It is the fashion to correct and fix so as to obtain a certain amount of chromatic aberration, a ruby tint being considered the best. This is to obviate the effect which the perfect achromatism of a glass of large numerical aperture has on the eye. Nevertheless this everlastingly recurring tint is objectionable and leads to misconception when dealing with extremely minute artificially coloured objects. The President's Address. By Prof. P. Martin Duncan. 181 Dr. G. E. Blackham has made some very practical remarks on the correction adjustment for homogeneous-immersion objectives,* which have appeared in our Journal. He meets the reasons for dispensing with an adjustment, viz. no risk of decentering, the existence of a one best position in all objectives, the cost of the adjustment, and the trouble. He very properly remarks that the decentering need not take place if the optician does his duty to the brass as well as to the glass, and that cost is quite out of the question if the thing is possible and is required. And he observes that although the shifting of the positions of the systems of lenses is only an expedient, yet if it can be shown that it reaches the desired end more certainly, speedily, and accurately than any other, the objection to it must fall to the ground. Dr. Blackham qualifies the term homogeneous immersion, stating that it is true as to the idea but not in practice, for there are differences between the refractive powers of the front lens of any objective and the medium, and the refractive powers of different samples of crown glass are not the same. In alluding to the method of correction he appears to favour Mr. Wenham’s mechanical process. He considers that the small adjustments can be made with more ease, rapidity, and accuracy by means of the screw-collar moving the back system of the objective than by means of the draw-tube. Our Honorary Fellow Dr. Dippel considers all this, and whilst admitting that the theory of correction is true, believes that most of the arguments in favour of correcting combinations of lenses on the homogeneous immersion are fallacious or of no value and weight. He admits that with the correction-collar we are not so strictly limited to an immersion fluid of a particular index of refraction, and also that the correction-collar allows the same objective to be used with a longer or shorter tube, whilst its absence entails the employment of an objective within very narrow limits of tube length. He would have an average correction made and all screwed down hard and fast, believing that more errors will ensue after meddling with the normal correction than occurred before without any attempt at correction. In concluding these references to the correction of objectives I cannot do better than quote Professor Abbe :—“ Increase of aperture is inseparable from a rapid increase of sensibility of the objectives for slight deviations from the conditions of perfect correc- tion. ‘The state of correction of an objective depends on the thickness of the refracting film between the radiant and the front lens, represented by the cover-glass and that portion of the pre- paration which is above the actual focus. This is a variable element independent of the objective itself. In order to avoid large aberrations which must result from the change of that element, * Proc. Amer. Soc. Micr., 1881, pp. 61-4. 182 Transactions of the Society. its variation must either be confined to narrow limits or must be compensated for by a corresponding change in the objective. Now there is a great difference in regard to this requirement between the objectives of low and wide aperture, in particular with the dry system. An objective of a few degrees is almost insensible, it may be focussed at the bottom of a trough of water without any loss of performance. With 30° differences in the cover-glasses within the usual limits are still inappreciable, and an object may be seen at the depth of a drop hanging on the under surface of a cover-glass. With 60° a deviation of the cover-glass from its standard thickness by not more than 0'1 mm., or a corresponding increase of the depth of the preparation above the actual focus, will introduce perceptible aberrations and a visible loss of definition if not com- pensated for. With an aperture exceeding 100° in a dry lens the same result will arise from a change of thickness of 0°02 mm. only. To preserve the best correction in such a system would necessitate a change of the correction-collar for almost every change of focus in the inspection of successive layers, unless the prepara- tion is exceedingly thin.” There can be no doubt that the majority of the recorded histology of the minuter structures will have to be worked over again with carefully corrected objectives. Amongst the many excellent inventions for facilitating earnest, and of necessity, rapid microscopical work the apparently trivial arrangement perfected by Mr. E. M. Nelson, for changing objectives, must commend itself to every one. It facilitates the rapid inter- change of objectives without the necessity of triple or quadruple nose-pieces and, in fact, will do away with the necessity of employing a nose-piece at all, a proceeding greatly to be commended, for those implements are often slip-shod abominations and bringers of error. It is interesting to find that the invention utilizes a warlike appliance, and that breech-loading cannon, those latest develop- ments of civilization in which, according to Herbert Spencer, the greatest admiration is obtained by those men who kill their enemies, have been studied and copied for the purposes of a pursuit which amongst others is making men more thoughtful and amenable to reason. Probably the Nelson adapter will replace the screw at some time or other, and it certainly cannot have some of the demerits of a coarse short thread, which is bound to interfere with the proper plane of the object-glass, and with the correct axial path of the rays into the body of the instrument. In concluding these remarks on the Microscope itself I must enter a protest against the clumsy method of pushing a glass slide with a valuable and important object upon it with the fingers, under the objective and moving it about. Cheapness of the instrument and The President's Address. By Prof. P. Martin Duncan. 183 want of scientific care are the temptations to and the causes of this very frequent source of error, which is intensified by the common fault of want of perfect flatness of the plane surface of the stand. The beautiful adaptation of a sliding glass restricted by a point, whilst it relieves the microscopist from the expenditure involved by a complicated brass movement, is so easily fitted that there is no excuse for employing the fingers alone. Some very remarkable communications have been made to the Society during the past twelve months, and one in particular marks an epoch in the science of microscopy. Whoever would have thought a few years ago of mounting objects in such media as bisulphide of carbon and phosphorus, and a solution of biniodide of mercury and iodide of potassium? Mr. Stephenson’s paper places the results of these solutions before the world, and his intro- duction is explanatory of the philosophy of the relation of the refractive media in which the object is mounted, to the numerical aperture of the objective. Almost as important as these new media, are the instruments which have been described in our Journal for slicing preparations. Some of these are marvels of ingenuity, and especially that one which employs the freezing apparatus as an adjunct. Mr. Michael has continued his remarkable studies of the British Oribatide, and it is difficult to know which to admire most, the beautiful construction of the objects or the extreme care and ingenuity displayed in dissecting and mounting them. The direction of microscopic research, however, has not been so much amongst the higher invertebrata, although great work has been done in them, as in relation to those legions of microscopic beings which are now shown to be a fertile source of misery to the human race. The most careful researches of old and the former study of the pathology of many fatal, so-called constitutional, diseases failed to bring their cause before the practitioner. Yet common sense and great experience had indicated to Holland, in the early part of this century, that germs or living entities were a vera causa. It required the present perfection of the Microscope and the development of the method of preparation and colouring to demon- strate bacteria in the tissues, to identify the bacteria of special diseases, and last, not least, to exhibit plainly and definitely the bacteria of phthisis pulmonalis. Researches on the bacteria of septicaemia by Mr. Dowdeswell, on organisms in the excreta of animals and birds, and in ice, by Dr. Maddox, have appeared in the pages of the Journal, and they form but a small fraction of the immense literature of these lowly organized things. Certainly the Microscope has not done all in these investigations, for an elaborate chemistry has enabled skilled workers to stain and decolour, the bacteria remaining tinted. 184 Transactions of the Society. A visible danger is better to face than the unknown: the one is possible of antagonism, the other is a terror. It may happen that now the Microscope has shown the minute bodies which accompany disease and which may produce it, it may lead to the discovery of the remedies. ‘The competition in the research just alluded to is immense, and new methods are constantly being invented. They are great additions to science and may be the beginning of a new era in the great profession of medicine. In concluding the former address which I had the honour of delivering to you at our last anniversary, I had the sorrowful duty of recording the death of one of the fathers of histological science, of a man who went to his rest full of honours and with the well merited reputation of a founder of a great theory. On this occasion I cannot help alluding to the loss this Society and science have sustained by the death of Professor F. M. Balfour, F.R.S., one of our Vice-Presidents. It is a saying as old as Grecian tragedy that those whom the gods love die young. Of rare promise, of gentle nurture, of singular modesty, this young but advanced student of nature will always be remembered with feelings of sincere sorrow and well merited admiration. He was a thorough scientist, and he laboured for truth’s sake, caring little for that personal distinction which a happy combination of circumstances gave him at his early age. Gear.) VI.—The Action of Tannin on the Cilia of Infusoria, with Remarks on the use of Solution of Sulphurous Oxide in Alcohol. By Hunry J. Wappineron. (Read 14th March, 1883.) I am desirous of bringing to the notice of the Society this evening a matter which, though small in itself, may be of some use in the hands of experts. The immediate subject is the peculiar action of tannic acid on the cilia of Paramecium Aurelia ; but I may, perhaps, be allowed to digress a little at starting, in order that I may call attention to the methods I have used for keeping Infusoria for microscopical observation. There are two methods which I have found very useful for this purpose. If small fragments of very hard burnt biscuit are dropped into water containmg Infusoria, and held in suspen- sion by pieces of weed or Conferve, these crumbs, after a short time, form a nucleus from which fungoid growths spring freely, so that from a fragment of biscuit 1-32nd in. in diameter we may have a spherical growth of 3-4ths in. in diameter. These growths seem to be peculiarly fitted for the development of certain kinds of Infusoria, and they have this advantage—that when lifted out of the water, the filaments necessarily collapse, and act as a net to inclose whatever may be among them. When placed on a slip, a portion of these filaments may be spread out with needles, and they then serve the purpose of so retarding the motions of the Infusoria that their observation is comparatively easy, the extreme fineness of the filaments allowing the highest powers to be successfully used. It is necessary that the biscuit should be very hard and well baked, otherwise the fragments disintegrate. This method applies to Tnfusoria in aquaria, or in comparatively large quantities of water ; but where they are contained in small troughs, I find that they thrive well on leaves of Anacharis or filaments of Conferve, which have been reduced to a pulp with a little water in a mortar. If a few drops of this are occasionally added to the trough con- taining the Infusoria, they may be kept satisfactorily for a length of time. The small trough I have here to-night hag been so kept for more than four months. . In trying the effect of various chemicals on Infusoria—princi- pally Paramecium Awrelia—I was led to use a solution of tannin, or tannic acid; and I was surprised to find that the immediate action of this chemical was to render the cilia visible without any manipulation of the light. It may have been noticed that when these Infusoria have been killed by ordinary means, such as heating the water in which they are contained, the cilia are very difficult 186 © Transactions of the Society. to observe, probably owing to their great transparency; so that no correct idea has, I think, been obtained of their size or quantity. On placing, however, a drop of water containnmg Paramecia on a slip side by side with a minute quantity of a solution of tannin, and making a junction of the two, it will be seen that the instant the Paramecia approach the mixed fluids their motion is arrested, of course in a greater or less degree according to the strength of the tannin. They are generally rendered perfectly quiescent, and the cilia begin to appear and continue to develope, until the body of the animalcule appears entirely surrounded by them. The symmetry of the cilia depends much upon the strength of the solution ; if it is too weak, it seems as if the animal had had time to slightly move the cilia, by struggling, as it were, as they appear crossed and crumpled; but if the solution of tannin happens to have mixed with the water in a better proportion, the cilia are more rapidly developed, and stand out almost parallel, hardly one being seen to overlap another. (See figs. 33 and 34.) * EiG. 30. Paramecium after treatment with weak Paramecium after treatment solution of tannin. with a stronger solution. To bring out the best appearance of the cilia over the whole of the surface of the Paramecium, the parabola is required; the animal then appears as if it were supported on the slip by its cilia. If the tannin solution is strong, the Paramecium is almost instantly rendered motionless, and the cilia appear to be entirely removed, remaining in a more or less confused state at the ex- tremity. I have shown this action to several microscopists; and so contrary is the remarkable development of the cilia to received ideas, that on nearly every occasion I have been met with the remark that they were not cilia but fungoid growths. This is, however, entirely disproved by the fact that they are developed, as it were, instantaneously. The action of the tannin on the cilia I believe to be analogous to its action on gelatine, rendering them leathery, and consequently * In fig. 33 the cilia should appear rather more crossed and crumpled than they are there shown to be. es The Action of Tannin, &c. By H. J. Waddington. 187 opaque. It does not appear to kill the Parameciwm itself—at least for some little time, unless the solution is very strong, as the rhythmical contraction and expansion of the contractile vesicles may be still observed. In the most successful observations it is probable that the tannin solution has been of sufficient strength to act upon the very delicate cilia, and, as it were, to paralyse them; while it has not been of sufficient strength to kill the animal outright. In the face of the accepted theory that ciliary motion is involuntary, it would be incorrect to say that the tannin acts upon the cilia in such a manner as to render them beyond the animal’s control; but the cilia are certainly rendered inert, while the functions of the animal are but little impaired for a time. The form of tannin which I have found most convenient to use is the glycerole of tannin, which is merely tannin dissolved in glycerine in the proportions of one part to four. It is a thick, viscid body, very stable, easily miscible with water, and conse- quently very manageable, as the quantity added to the water under examination can be well adjusted, and the action is more satisfac- tory than it would be if a solution of nearly the same specific gravity as water were used. Tannin in alcohol is not advisable on account principally of the repellent action between the alcohol and the water. That the immediate action of the tannin in moderate quantity is not to kill the Paramecium is, I think, apparent from the fact that Infusoria much more minute than Paramzcia seem to be little affected by it. I have constantly seen these become entangled in the cilia of Paramezciwm that had been rendered motionless by tannin, and extricate themselves after a time apparently little affected by it. But such Infusoria have not possessed cilia of the same character as Paramecium. On Stylonychia the tannin does not appear to have so decided an action, and whenever the cilia take the form of sete the Infusoria seem much more capable of resisting its paralysing action, the peculiar jerky motion of the setz being kept up for some time. I have made the remark that I think no correct ideas have hitherto been held as to the size and quantity of the cilia; at any rate, I have never seen any drawing, or read any description of Paramecium, as it is observed after the treatment by tannin. That the appearances observed are really cilia may be easily verified by the action of osmic acid, which kills the Paramecowm at once, and renders the cilia visible, but not to the extent that they are so rendered by the tannin. I may also make allusion to the action of another chemical body on Infusoria, and to the advantages it seems to possess in micro- scopical research. This body is sulphurous acid, or, in the form in which I have found it most useful, solution of sulphurous oxide in 188 Transactions of the Society. alcohol. The properties of sulphurous oxide are too well known to require any comment. I will merely mention that it is soluble to the extent of 30 volumes in 1 volume of cold water; but this solution soon changes into sulphuric acid by the action of air. If, however, the gas is passed into alcohol the quantity absorbed is greatly increased. If this saturated solution of the gas in alcohol is added to water, the gas, or the greater portion of it, is instantly thrown off. This alcoholic solution I have found most satisfactory in the observation of Infusoria. When a minute quantity is added to a drop of water or a slip, there is at first the repellent action between the alcohol and the water. This being overcome, the gas is given off, and its effect upon infusorial life is at once apparent. If the solution is strong, they are at once killed, and in most cases, if the Infusoria are ciliate, the cilia are rendered visible; but if the solution has been strong enough to be hurtful but not deadly, examination may be carried on very satisfactorily. The Infusoria are rendered almost motionless, while the ciliary action may be well observed. If, under these conditions, the slip containing Paramecia is allowed to become dry, the points of attachment of the cilia to the body of the animal are exceedingly well defined. Where the cilia have become detached, they almost resemble raphides. I think that this reagent—sulphurous oxide in alcohol—is one that may prove of great use in microscopy. It is not so deadly as osmic acid, but it has a very marked action on Infusoria ; while it is by no means so dangerous, and its cost is much less. The solution in water possesses very powerful bleaching properties, and the alco- holic solution, which is perfectly stable, furnishes a ready means of obtaining small quantities of sulphurous acid, for bleaching or other purposes. I would merely add in conclusion that I consider I ought almost to apologize for dealing with a subject so very foreign to my usual microscopical pursuits. The experiments I have described have been carried out more as a microscopical recreation than as a scientific research ; but they have appeared to me, and to those microscopists to whom I have shown them, to be of so much interest, and so capable in the hands of those more conversant with the subject. than myself of further extension, that I have been induced to bring them forward. (Gales SUMMARY OF OURRENT RESEARCHES RELATING TO ZQOL OGY AND. BOTANY (principally Invertebrata and Cryptogamia), MICROSCOPY, .&c., INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.* ZOOLOGY. A. GENERAL, including Embryology and Histology of the Vertebrata. Development of the Ovum of Arvicola arvalis.t—The following are the chief points of C. Kupffer’s investigation into the alleged reversal of the positions of the germ-layers in certain Rodents. 1. The ovum of the field-mouse forms a normal blastoderm, show- ing lamination in the region of the germinal disk, like the ovum of the rabbit. 2. The peculiarities of the field-mouse’s ovum are caused by the covering-layer, which, instead of disappearing, as in the rabbit’s ovum, proliferates and forms a plug which invaginates the active pole of the ovum. It is this invagination, thus brought about by an accessory growth, which causes the apparent reversal of the germ- layers. : 3. With the exception of this invagination the course of develop- ment is normal. A complete yolk-sac is produced, and, judging by early stages, an amnion also, in the usual manner. 4, The mesoderm appears in the neighbourhood of a swelling, which is formed at a point in the periphery of the area embryonalis, and is to be regarded as a cecal evagination of the ectoderm into the cavity of the yolk-sac. This swelling may with great probability be described as the commencement of the allantois. 5. Although differences have already been known to exist between the field-mouse’s ovum, after assuming the cylindrical form, and the corresponding stage of the guinea-pig’s ovum, it may nevertheless be stated as certain that Bischoff was right in interpreting the whole of the structure which he termed “ plug” or “ egg-cylinder,” as an ovum. * The Society are not to be considered responsible for the views of the authors of the papers referred to, nor for the manner in which those views may be expressed, the main object of this part of the Journal being to present a summary of the papers as actually published, so as to provide the Fellows with a guide to the additions made from time to time to the Library. Objections and corrections should therefore, for the most part, be addressed to the authors. (The Society are not intended to be denoted by the editorial ‘‘ we.”) + SB. Math.-phys. Kl. Akad. Wiss. Miinchen, xii. (1882) pp. 621-37 (1 pl.). 190 SUMMARY OF CURRENT RESEARCHES RELATING TO Reichert and Hansen held a different view, regarding as the ovum only a globular mass found in the free end of the cylinder. Formation of the Embryonic Layers in the Trout.* —L. F. Henneguy in dealing with the vexed question of the origin of the primary blastodermic layers in Teleostean Fishes, comes to con- clusions resembling those of Gétte. The first trace of the embryo appears as a thickening at one point in the margin of the germinal disk ; it is found from sections that the cellular layer which roofs in the segmentation-cavity, turns inwards towards the yolk at the margin of the disk, and penetrates this cavity ; the corneous layer forms no part of this fold, but ends on the surface of the yolk. At the projec- tion formed by the embryo, the blastoderm is thicker, and the inflected margin extends further into the cavity than elsewhere. At the pyri- form stage of the embryo, when the posterior extremity forms a slight projection on the edge of the disk, the cells are found to present a concentric arrangement around the axis of the embryo, as described by Oellacher ; the blastodermic layers are not distinct at this point, although in front of the caudal bud two are distinguishable in trans- verse sections made across the embryo, commencing at the caudal bud ; the three primitive layers are found in the lateral parts of the embryo and at the caudal end ; in the middle line only two, but below the axial cord (the commencement of the nervous system) is found the chorda dorsalis, formed from the lower part of the axial cord which originates from the primary endoderm at the same time as the meso- derm. In the anterior part of the embryo also, only the two layers are found. Longitudinal sections of this stage show the caudal bud to be formed of undifferentiated cells; in front of it, first two and then three layers are met with; the ectoderm increases in thickness from behind forwards, but suddenly becomes thin at the anterior ex- tremity. ‘The mesoderm, chorda dorsalis, and secondary endoderm only exist towards the middle of the embryo, and in front they become confounded with the primary endoderm. At that point in front of the caudal bud at which the three layers are developed, a peculiar vesicle appears in the secondary endoderm. The nervous axis is developed at the cost of the ectoderm and the corneous layer takes no part in its formation; from the first, it is clearly separated from the chorda dorsalis; when the medullary cleft is about to be formed, the central cells exhibit karyokinetic figures and divide; the daughter-cells separate, leaving between them a space, the future central canal. These cells are very delicate, whence has arisen the erroneous idea that they normally undergo destruction. Distinctions between Organisms and Minerals.t—Dr. H. Valin has repeated the interesting experiments of MM. Monnier and Vogt on the artificial production of organic forms. In a flask full of soluble glass were placed fragments of sulphate of iron, ten grains in weight, which immediately began to assume a * Comptes Rendus, xcv. (1882) pp. 1297-9. t Amer. Natural., xvii. (1883) pp. 233-4. t See this Journal, ii. (1882) p. 320. ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 191 colloid condition on the outside, and shot out tubular prolongations, colloidial and cellular, which grew at the rate of half an inch in twenty-four hours. Some attained to 2 in. in length, and were about 1-12th in. in diameter. All these prolongations shot out a number of slender filaments from various points of their surface, and these attained a length of a few inches in a few hours. After a few days or weeks all these assume a crystalline condition and become empty inside. Some of them rise to the surface of the liquid. They are insoluble in water, remain intact when exposed to air, and when introduced in a newly-prepared flask at the same time with fresh fragments, they hasten the metamorphosis of the latter. The addition of water to the soluble glass renders the experiments more easy and saves time. Watched under the Microscope, the fragments of sulphate of iron are seen to swell all around. An unctuous colloid mass is formed, which consists of fine granules perfectly similar to animal tissues. This mass stretches into prolongations, and fluid contents are seen to flow inside them. When the surface of some prolongations was opened, a semi-solid substance grew out of the opening into new prolongations. One of these mineral organisms, when placed on a fresh fragment, shot out new prolongations, as if real grafting had taken place. “ Organisms” of sulphate of copper, sulphate of zinc, alum, phos- phate of iron, &c., were similarly obtained, each possessing a form peculiar to itself and distinct from the others. Analogous forms grew in saccharated lime-water. Cellular bodies of the same mineral formed in solutions of alkaline carbonates. The following we transcribe verbatim from the report of the meeting at which the paper was read :— “These experiments relate to the almost unknown department of chemistry which treats of colloids, and as crystalline solutions grow into symmetrical crystals, so a colloid substance in process of forma- tion assumes a typical form, and must be the start of all forms in animals and plants. These so-called mineral organisms, viewed with the naked eye and the Microscope, or chemically tested, come as near to the lower animals and plants as these are from one another, and form a new field of investigation for the biologist. Wecan no longer say that only living things grow, unless we reckon these as living. “ Among the conclusions of Dr. Valin’s paper were these: ‘ That the vitality of growth of these mineral organisms consists in the passage of a crystal into a colloid, and is thus correlated, but not identical, with the kinetic process known as crystallization. That the molecule of the bodies consists of many elements, and that acid and alkaline polarities are always concerned in their growth, for only acid minerals in alkaline solutions gave rise to them. That we have a right to suppose that living protoplasm is nothing but a highly complex mineral organism in favourable media (water and air).’ “This would tend to confirm the growing belief among biologists, that life is nothing but the energy manifested by the forty and odd (Reinke) proximate principles which constitute protoplasm, when they pass from the crystalline or soluble into the colloid state in the proper media,” 192 SUMMARY OF CURRENT RESEARCHES RELATING TO B. INVERTEBRATA. Mollusca. Development of Reproductive Organs of Pulmonate Mollusca.* —H. Rouzaud finds that the reproductive organs of the Pulmonata arise from an ectodermic bud, which is primitively simple and clavi- form, and which he calls the primitive bud. The hermaphrodite gland is merely the free ramified apex of this bud. The bud itself is formed by the cutaneous envelope in the region which separates the head from the pallial “collar,” and always arises at the spot at which the common or the female orifice is afterwards developed. At first clavi- form, it becomes cylindrical, and, following the general integument, soon extends to the level of the liver. Its basal region soon gives rise to a secondary bud, the rudiment of the penis, of the male efferent canal, and of the flagellum. At its free end this bud soon presents a tract of muscular tissue which is connected with the wall of the body, and is the representative of the future retractor muscle of the penis. Inferiorly to this, there is developed another bud—the sagittal— which is the rudiment of the dart-sac. Ina large number of so-called Helices the base of the sagittal bud also proliferates and gives rise to a certain number of tertiary buds which form the glands or multifid vesicles ; these should, however, be regarded as parts of the dart-sace. The median region now presents two clefts, which are distinguished as the utero-copulative, and the utero-deferent. With the former there becomes connected the copulatory pouch, and with the latter the oviduct. The arrangement of the parts are such that the dart and the “ copulatory cellular layer” are the symmetrical homologues of the penis and the efferent canal. There are, then, three tracts of cells; the median one, which is the oviduct, gives rise to the albuminiparous gland. While these changes have been going on, the tip of the primitive bud has been actively proliferating, and has given rise to a number of rudimentary lobules of the hermaphrodite gland. The sexual products would appear to be derived from the ectoderm. Developmental History of the Prosobranchiata.t— Dr. Carl Rabl’s memoir is divided into two parts—the first treating of the question of the ultimate fate of the gastrula-mouth in Paludina vivipara, while the second relates to some later developmental pro- cesses in Bythinia tentaculata. The question of the fate of the gastrula-mouth is of great theoretical importance ; and there is at present scarcely a point in developmental history about which there has been more dispute, and upon which opinions are more divided. The author finds that in Paludina vivipara the gastrula-mouth gradually but completely closes in the median line of the ventral surface; that, further, soon after its closure the anus makes its appearance, but is in no way connected with the gastrula-mouth; and that, lastly, the permanent mouth * Comptes Rendus, xevi. (1883) pp. 273-6. y+ Anzeig. Akad. Wiss. Wien, Jan. 18, 1883, p. 13. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 193 appears at the spot where the last residue of the gastrula-mouth had closed up. These statements are certainly in contradiction to those ‘of some other authors, but show that a common mode of development may be set up, at least for the Gasteropoda. The second part treats of the structure of the velum, the origin of the upper cesophageal ganglion, the structure of the primitive kidneys and the intestine, and of the development of the persistent kidneys. The author finds that the velum in Bythinia is composed of large cells containing vacuoles, and differs in some other characters from the corresponding organ of other Gasteropod embryos; that the superior cesophageal ganglion originates in the form of a thickening of the outer germ-lamella (vertical plate); that the primitive kidneys are composed of a few, not very large, perforated cells; that the foundation of the persistent kidneys stands in no genetic relation to the ectoderm ; and, finally, that in some respects the intestine possesses interesting peculiarities. The author has endeavoured to bring these results into agreement with his previous statements upon the development of Planorbis, and to show that the same laws which had proved to prevail in the case of Planorbis apply also to Bythinia, and that the differences result from the greater abundance of nutritive vitellus which is presented by the germs of the latter. Norwegian Buccinide.*—H. Friele describes the Buccinide of the Norwegian Arctic Expedition, which may be said to be especially at home in the arctic and northern seas of both hemispheres. According to the views of the author, this family comprises the genera Jumala with one species, Volutopsis with one species, Pyrolo- fusus with one species, Neptunea (recte Neptunia sew potius Neptunina) with seventeen species, T'roschelia with one species, and Buccinum with twelve species; in all six genera and thirty-three species. The varieties of other species are also noticed. Ten species are for the first time described and figured. It may be doubted whether the grounds of distinction between these genera are sufficient, and whether they are not all merely sections of the Lamarckian genus Fusus and the restricted genus Buccinum. The author attaches con- siderable importance to the dentition as a generic character; but this is, at any rate, a difficult basis of classification. What are we to do with the fossil, and consequently now toothless, Gastropods? The _ structure, and even the presence of the odontophore, in that order of Mollusca depends on the nature of their food. Herr Friele has con- clusively proved that in the Buccinide “ diversity of dentition affords anything but a trustworthy guide” in distinguishing species. One important character of such distinction has not been lost sight of by him, viz. the shape of the apex or embryonic whorls. Sinisigera.j—A. E. Craven, who has published a monograph on this genus, now states that he has been satisfied as to the shells of * ——_ ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 965 MICROSCOPY. a, Instruments, Accessories, &c. Coppock’s Combination Microscope.—This Microscope has been constructed by Mr. C. Coppock mainly from data obtained from con- sultation with the leading teachers of science in Edinburgh. The general form of the instrument is shown in fig. 36, the stage ——————S ly \ i Hi | AY and body being carried upon a turned pillar, after the style of the Continental models, and the stage being as large as is consistent with the relative proportions of the whole instrument. The body-tube allows the highest objectives to be readily focussed by giving a slight spiral movement to the tube, and the draw-tube is stopped when drawn out to the normal nine inches. The side condenser is fixed by 266 SUMMARY OF CURRENT RESEARCHES RELATING TO a revolving annulus to the body. The revolving diaphragm plate is recessed into the stage. When the largest aperture is used, the thread in the stage will allow of a fitting being screwed into it to receive the various stage apparatus. For class demonstration it is found that the hinged joint to the limb is not essential, and it is therefore made in two forms, with and without joint. Crouch’s Portable Histological Microscope.—Mr. H. Crouch has Fia. 37. —— SS oz ™=a£=_“== == ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 267 issued the instrument shown in figs. 37 and 38, with the view of pro- viding a Microscope which shall combine portability with more steadiness than is usually found in “portable” forms. When set up for use the instrument is shown in fig. 37, and when folded in fig. 38. The modifications adopted to enable the instrument to be folded Fic. 38. up are as follows :—(1) The stage is made to turn laterally at right angles to the normal position, so as to be in a line parallel with the body-tube, which permits the latter to be reversed and inserted at the lower end of the socket; and (2) the two front “feet” of the tripod are made to fold outwards and backwards under the heel. ' In packing the instrument, a small milled screw beneath the stage is loosened, and the stage turned at right angles; the body-tube is removed, reversed, and put into the socket at the lower end; the limb 268 SUMMARY OF CURRENT RESEARCHES RELATING TO is inclined backwards on the trunnion axis as far as it will go, and the feet are turned back under the heel. Thus folded, the Microscope fits into a leather case 7 in. x 5 in. X 3 in. The stage, which is only } in. thick, contains between its upper and lower plates a diaphragm with four circular apertures, which is rotated by the finger acting on its projecting milled edge at the right- hand side. Deecke’s Large Microscope.—Dr. T. Deecke, special pathologist ot the New York State Lunatic Asylum, sends us a description of this instrument (figs. 39-41)* from which the following is condensed :— The stand became a necessity after he had succeeded in making Fic. 39. ie Coy Vn D | T | | | = Il ) Vi.: sections of 1-400th to 1-600th in. thickness, and upwards of 6 in. in _ diameter, in order to facilitate topographical investigations of minute * The figures are drawn to a scale of about 1-12th actual size. ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 269 anatomical structure. It was constructed in 1876, and has since been in constant use for ordinary observations and photomicrography. Fia, 40. The application of a mechanical stage nearly 12 in. square, per- mitting 4 in. of motion in all directions from the optic axis, necessitated sundry modifications of design and construction from the usual models Fig. 41. ii Aa 22 QinunuUistite in order to secure the utmost freedom for the various manipulations, to- gether with the accuracy of movement required in using high powers. 270 SUMMARY OF CURRENT RESEARCHES RELATING TO The chief novelty is the system of inclining the Microscope from the vertical to the horizontal. The foot is a heavy triangular plate, the base 14 in. and the two sides 19in. There are two short pillars at the angles of the base which support by pivots a second triangle connected at the truncated vertex by a hinge with a shoulder-piece encircling the main column in which the coarse adjustment slides; the continuation of this shoulder in front is the fixed stage-plate carrying the mechanical stage. The lower end of the main column is provided with a female screw in a pivoted sliding box-fitting, in which acts a powerful 12 in. screw attached to the base-plate and controlled by a crank at the back. This screw causes the main column to travel from the vertical to the horizontal, the suspended triangle at the back moving correspondingly as a hinged stanchion. The coarse adjustment is similar to that in the older Ross model ; but two racks are applied to the column and two pinions are set on the same axis so that the teeth grip alternately in the racks, by which it is stated that lost motion is obviated. The fine adjustment is also on the older Ross principle. In consequence of the great length of the arm (133 in.) carrying the body-tube, and to avoid flexure and tremor, the lever is constructed of two strong double bars connected by cross-bars like the beam of a chemical balance. It moves between conical steel fulcrum-points placed considerably in front of the centre, and very strong flat springs press against each end. Upon the posterior arm of the lever a micro- meter-screw of sixty threads to the inch, acts, giving a focussing range of 1-8th in. The mechanical stage rests upon the fixed rectangular plate which forms one piece with the shoulder encircling the main column. The mechanical movements (4 in. in all directions from the optic axis) are obtained by means of two sliding plates of the usual construc- tion, but with modifications in the mechanism necessitated by the increase of size and greater range of motion. The lower stage-plate is 12 in. from behind forward and 11} in. wide, and the upper 12 in. by llin. The ordinary rackwork motion of the upper plate was found to be too coarse when high powers were employed, and an arrange- ment was therefore devised by which this rackwork can be discon- nected and the plate then moved by a system of four endless screws on the left of the stage. Stage clips of somewhat peculiar form allow a slide of any size from the ordinary one to upwards of 10 in. by 8 in. to be securely held. At the lower end of the upper stage- -plate a pair of movable legs (like compasses) are applied on one axis, and can be set by a screw at any angle from 10° to 160°, the end-pieces being provided with grooves for the reception of the slides. An adjustable right- angled arm is attached to the upper left-hand corner of the same plate, and can be pressed against the slide. A centering substage, carrying accessory apparatus, is also applied ; it is provided with rack and pinion movement actuated by the small milled head on the right in fig. 40. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. Zia The mirror has seven jointed arms, and can be used above the stage for illuminating opaque objects. The whole instrument stands upon a strongly made tripod 15 in. high with revolving top 20 in. in diameter. When at an inclination of 45° the eye-piece is 33 ft. from the floor. - The Microscope was constructed under Dr. Deecke’s supervision, and from plans drawn by himself, at the “ Utica Engine and Boiler Works” of Mr. P. 8. Curtis, Utica, N.Y. Dr. Deecke also sends us a description of a stage for use in photo- micrography for the purpose of rendering possible the focussing of large areas of sections when low magnifying powers are used. An ordinary photographic lens can be successfully employed instead of the microscopic objective. It gives at a proper distance, of from 10 to 20 or even 40 ft. from the lens, a picture of Fic, 42. excellent definition, but the great difficulty is to bring all parts of a field of such dimensions into the proper focus. Assuming that this ed difficulty probably origi- nated in slight inequalities in the thickness of the sections in their different parts, or that it was due to their position in the mounting fluid between the slide and the cover-glass, Dr. Deecke corrected the defect by constructing a stage on which the speci- men may be placed in any desired plane slightly oblique to a vertical plane drawn through the centre of the magnifying lens, and thus arrived at results which gave perfect satis- ==) \ _ = faction.* =i Lys Robin’s (Chevalier) Tm TTT TT Dissecting Microscope— == This (fig. 42) is another form (by A. Chevalier) of ore Prof. C. Robin’s Dissecting Microscope, that made by MM. Nachet having been figured on p. 100, Vol. IT. (1882). * Description supplied by Dr. Deecke. See also brief note in Proc. Amer. Soc. Micr., 5th Ann. Meeting, 1882, pp. 277-9. No little credit is due to Mr. G. W. Ruffle for engraving the above woodcuts from photographs very much wanting in clearness. ~+ Cf. also C. Robin’s ‘ Traité du Microscope,’ 1877, p. 75. 272, SUMMARY OF CURRENT RESEARCHES RELATING TO The stage is intended to be used with transparent objects. The central aperture receives either a wheel of diaphragms or a glass disk. An erecting prism is shown in place over the eye-piece. When opaque objects are required to be observed they are placed on the base-plate, the plate carrying the two pillars, mirror, and stage being then removed by loosening the two clamp screws at the corners. Rollet’s Polari-spectro-microscope.*—This instrument was de- vised by Dr. A. Rollet, of Graz, and is a combination of a compound Microscope with a spectral and polarizing apparatus, he having observed, whilst experimenting on the spectra of the colours of thin plates, and the polarization colours of selenite films, that such a combination might be exceedingly useful for certain histological examinations. The description of the instrument and its use is prefaced by some remarks on the spectroscopic eye-pieces hitherto designed, beginning with the original plan by which parts of a spectrum (or a small spectrum suiting the field) were projected in the plane of the micro- scopical object. This was effected by spectral apparatus fixed in front of the objective, and thus observations could be made on the behaviour of microscopical objects in monochromatic light. Later the spectroscopic eye-piece was adopted, on the suggestion of Dr. W. Huggins, on the model of a star spectroscope, and after- wards improved by the spectroscopic eye-pieces, especially adapted for the Microscope, of Sorby and Browning, Zeiss, and others. Each of these methods, however, serves different purposes; and careful consideration shows that it is only the older manner of examina- tion which is adapted for true microscopical studies of a more extended application, the use of the spectroscopic eye-piece being much more circumscribed. In the latter the slit is at the point where the inverted image is formed by the objective and field-lens. A linear strip of this image is then spectrally analysed by a direct vision prism. Such an apparatus is excellently adapted for studying the absorption-spectra of uniformly coloured microscopical objects con- taining no inner contours, and whose images cover the slit either entirely or to a definite extent. It can also be used for the same purpose in the case of the absorption-spectrum of one particular absorbing substance which is associated with delicate bodies uniformly distributed in a liquid, as with the red blood-corpuscles or chlorophyll- grains. But in these cases the action of the eye-piece is satisfactory only if the object is somewhat above or below the focus of the Micro- scope. It is easy to see the reason for this, but an example will explain it more clearly. Place a drop of blood, spread out on a slide, under the Microscope, remove the prism of the eye-piece, and with the slit wide open focus so that the image of the blood-corpuscles may be as sharp as possible, then narrow the slit and replace the prism. A spectrum of unequal brightness will be seen, crossed by numerous dark lines and shadows at right angles to the direction of the slit, and in which both the Fraunhofer lines and the absorption-bands * Zeitschr. f. Instrumentenk., i, (1881) pp. 366-72 (3 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 273 will be indistinct and fragmentary. ‘This will also occur if the edges of the slit are defective or if particles of dust have got in. In the case we are considering it is caused by the sharp outlines of the blood- corpuscles. If the Microscope is placed out of focus a uniformly bright spectrum will be obtained with sharp Fraunhofer lines, and the distinct absorption-bands of the hemoglobin. A band of the Fie. 44. € SSH Uffisrarrrary TSA J Hp i HUAI EM CIN gs sharp image of the object is of course no longer spectrally analysed, but only a band of the circles of confusion, which now fall in the plane of the slit, forming there an indistinct image of the corpuscles. We have, however, in this way, removed the injurious action of their sharp outlines upon the clearness of the absorption spectrum.* * Besides the value of the spectroscopic eye-piece for the study of absorption- spectra, Dr. Rollet mentions the use he has made of it in the examination of Newton’s rings, and the polarization colours of crystalline plates. Ser, 2.—Vou. IIL. ay 274 SUMMARY OF OURRENT RESEARCHES RELATING TO “By the above remarks,” Dr. Rollet says, “I imagine I have sufficiently shown that the use of the spectroscopic eye-piece in microscopy is somewhat limited, but if it be objected to this that Sorby has made exceedingly numerous observations by this means, it may be replied that these researches were concerned only with the discovery of the characteristic absorption-spectra of colouring matters, that is, always for the solution of a particular problem for which this eye-piece is eminently fitted. There are, however, a large number of problems in micro-spectroscopic research for which the eye-piece is not suitable, i.e. all those in which it is not merely required to examine the absorption-spectra of the colouring matters occurring in microscopical objects, but the objects themselves in monochromatic light, whether in any particular part or all parts of the spectrum. For such purposes the spectrum projected in the plane of the object must be used as it was employed before the introduction of the more recent eye-piece.” The following description is then given of the polari-spectro- microscope which was constructed by Schmidt and Haensch of Berlin, according to Dr. Rollet’s directions. To a Microscope (fig. 43) in which the stage is further than usual from the base, the following pieces of accessory apparatus are fixed. I. Beneath the stage ¢, is a small spectroscope b attached to it by means of a metal plate a with an oval hole, and movable by the screw c horizontally from right to left in a slide applied to the metal plate. The spectroscope consists of the following parts (fig. 44):— (1) The slit s adjusted by the screw d; (2) a collimator lens e; (3) a direct-vision prism f; and (4) above the prism a convex lens of short focus g, which is intended ‘to project a small spectrum in the plane of the object on the stage. That this may be easily done with different objects, on slides of different thicknesses, the prism and the convex lens can be moved vertically, they being in one piece of tubing, while the slit and collimator lens are in another, This movement is effected by a screw h cut in the inner tube, and a ring ¢ (figs. 43 and 44) on the outer, which act like the correction-adjustment of objectives. (The amount of the vertical movement can be registered on a millimetre scale, divisions on the ring showing fractions of mm.) The dispersion of the prism is such that with a medium magnifying power, the small spectrum projected in the plane of the object, can be completely seen in the field of the Microscope, from the red to the violet end and the Fraunhofer lines also clearly visible. (5) In front of the slit is a polarizing (Hartnack-Prazmowski) prism k, and (6) above the convex-lens is fixed a selenite film e (Red I. Ord. or Red II. Ord.). II. Over the tube of the Microscope is an eye-piece o (fig. 43), above which a Hartnack-Prazmowski analysing prism is fixed. This is movable over the eye-piece by its tube p and its correct position is shown by an index g on the tube moving over a circular scale r fixed to the eye-piece. ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 275 The instrument, when intended to be used for the purposes here- after mentioned, must be adjusted as shown in fig. 45, which represents a projection upon a horizontal plane of the parts inter- posed between the eye and the mirror. ss Direction of the slit. pp 3 vibration of the polarizer. aa k es ri analyser. ; 00 ‘s es 5, ordinary ray in the selenite film. ee a 5 » extraordinary ray in the same. In this arrangement of the instrument, when sufficiently strong parallel rays are received from the mirror (either bright, diffused daylight, direct sunlight, petroleum- or gaslight), a dark interference- band will be seen in the spectrum in the field at the point corre- sponding to the Fraunhofer line EH, which moves from E to F or E to D, more or less according to the tint of the selenite film. The resulting intensity of the light proceeding from the analyser (apart from the loss at the surface) is under the above condition for every given colour R? = r? sin? a [On making vinegar and the vinegar plant. ] Knowledge, (11. (1883) pp. 114-5. a [Tool and implement-making processes” in lower organisms. (Sponges and Insects). ] Knowledge, III. (1883) p. 163. SuitH, J.—A Method of Making and Mounting Transparent Rock-sections for Microscopic Slides. Journ. Post. Micr. Soc., I. (1883) pp. 28-33 (2 figs.). Tscurrcu, A.—Micro-chemical reaction Methods. [ Post.] Journ. Chem. Soc. Abstr., XLIV. (1883) pp. 376-8, from Arch. Pharm., XX. (1882) pp. 801-12. Van Brunt, C.—Removing air from Diatoms. [The frustules are dried on the cover-glass, which is then placed on a slide, diatoms up, and plain balsam is dropped upon them. By heat the balsam is caused to flow round the diatoms. It does not replace all the air within them, but by alternately heating the balsam up to the boiling-point and then cooling it, two or three times, all the air can be expelled. | Amer. Mon. Micr. Journ., TV. (1883) p. 39. Vorce, C. M.—The Detection of Adulteration in Food. Illustrated. Amer. Mon. Micr. Journ., TY. (1883) pp. 24-6, Watmsiny, W. H.—Some hints on the preparation and mounting of microscopic objects. IV. [Fluid mountings—best method of using the fluids and rendering the mount permanent. | The Microscope, II. (1883) pp. 179-86 (5 figs.). Wincue.., A.—The use of the Microscope in Geology. {Suggestions to use the Microscope for the examination of fossil corals and Brachiopoda, Hozoon, and rock sections. | The Microscope, II. (1883) pp. 177-9. Wyss, H. von. See Ranvier, L. ti ESD 3) PROCEEDINGS OF THE SOCIETY. Awynvat Meetine oF 141TH Fepruary, 1883, at Krne’s CoLiece, Srranp, W.C., tHE Presipent (Pror. P, Martin Duncay, F.RS.), IN THE CHAIR. The Minutes of the meeting of 10th January last were read and confirmed, and were signed by the Chairman. The Treasurer (Dr. Beale, F.R.S.) read his Statement of the Income and Expenditure of the Society for the past year (see p. 316). The adoption of the Treasurer’s Statement was moved by Dr. Millar and seconded by Mr. Groves, and carried unanimously. The Report of the Council was read by Mr. Crisp (see p. 315). The adoption of the Report was moved by Mr. Curties and seconded by Mr. Beck, who said that he did so with very great pleasure as he felt that the energy which was shown in the conduct of the Society’s affairs was deserving of the highest praise. Mr. Beck also made some remarks on the loan of books from the Library, to which Mr. Crisp replied. The List of Fellows proposed as Officers and Council for the ensuing year was read as follows :— President—Prof. P. Martin Duncan, M.B., F.R.S. Vice-Presidents—Robert Braithwaite, Esq., M.D., M.R.CS., F.LS.; *James Glaisher, Esq., F.R.S., F.R.A.S.; Robert Hudson, Esq., E.R.S., F.L.S.; *Charles Stewart, Esq., M.R.C.S., F.L.S. Treasurer—Lionel 8. Beale, Esq., M.B., F.R.C.P., F.R.S. Secretaries—F rank Crisp, Esq., LL.B., B.A., V.P. & Treas. LS. ; *Prof. F. Jeffrey Bell, M.A., F.ZS. Twelve other Members of Council—*John Anthony, Esq., M.D., F.R.C.P.L.; *Alfred William Bennett, Esq., M.A., B.Sc., F.L.S.; *William John Gray, Esq., M.D.; J. William Groves, Esq.; A. de Souza Guimaraens, Esq.; John H. Ingpen, Esq.; *John Matthews, Esq., M.D.; John Mayall, Esq., jun.; Albert D. Michael, Esq., F.L.S.; John Millar, Esq., L.R.C.P., F.L.8.; William Thomas Suffolk, Esq.; Frederick H. Ward, Esq., M.R.C.S. Mr. Beck and Mr. Reed having been appointed Scrutineers by the President the ballot was proceeded with, and the Scrutineers having handed in their certificate of the result of the ballot, the President declared the Fellows who had been nominated to be duly elected as Officers and Council for the ensuing year. Mr. Glaisher said it would be noticed that in the list just read the name of Mr. Stewart no longer appeared as one of their Secretaries ; * Have not held during the preceding year the office for which they were nominated. 314 PROCEEDINGS OF THE SOCIETY. and he rose to ask the Meeting to give to that gentleman the very warmest possible vote of thanks for the eminently’valuable services which he had rendered to the Society. They all knew his readiness to assist at their meetings, and how ably he had come forward at all times to illustrate not only his own but the communications of other Fellows, and in this and other ways had laid all the Fellows of the Society under the greatest debt of gratitude to him. Mr. Beck seconded the motion as it had been his privilege ten years ago to propose Mr. Stewart as Secretary, and most cordially agreed with the mover of the vote of thanks as to the value of the services which had been so efficiently rendered to the Society. The President, having put the vote to the Meeting and declared it to be carried by acclamation, said that he could only express his entire concurrence with the terms of the resolution and his personal regret that they were about to lose Mr. Stewart's compantonship. He hoped, however, that it would be found that Mr. Stewart’s engage- ments would not prevent him on some future occasion from accepting some other office in connection with the Society. Mr. Stewart in acknowledgment said he could only thank the Fellows for the very hearty way in which they had acknowledged his efforts to serve them, having, however, a strong sense of his own shortcomings, so that he could hardly recognize the description given by the mover of the resolution as applying to himself. The President then read his Address (see p. 172). Mr. Michael said he felt it was hardly necessary for him to ask the Meeting to join in a cordial vote of thanks to the President for the useful address to which they had just been listening, reminding them of many points which they were apt to let slip from their memories. Dr. Millar having seconded the motion, it was put to the Meeting and carried unanimously. Mr. Crisp moved a vote of thanks to the Auditors and Scrutineers, which being duly seconded, was put to the Meeting and carried unanimously. Mr. Beck, in returning thanks, said he could not sit down without alluding to the loss which had been sustained by science in the death of Professor Balfour, whom their Society was honoured by counting as one of their Vice-Presidents, and whose memory would not for a long time fade away. Mr. Creese exhibited a new turntable, which was described by Mr. Stewart (see p. 308). Mr. John Mayall, jun., called attention to the fact that Dr. Zeiss had adapted the correction-collar to his homogeneous-immersion objectives, the first of which class he exhibited. The correction was not, however, so much intended to correct the effect of the cover-glass PROCEEDINGS OF THE SOCIETY. 315 as to enable the objective to be used upon instruments haying the longer tubes with which English instruments as compared with Con- tinental ones were furnished. The tube-length allowed for was from 20 cm. to 40 cm. Mr, Crisp made a statement in explanation of the non-publication of the paper by Prof. Abbe, which was laid before the Society in June 1880, the author not having found an opportunity to put it into shape for printing, and preferring in consequence to withdraw it trom publication. Some remarks were made by Mr. Curties, Mr. Beck, and others, and a letter from Prof. Abbe on the subject read. New Fellows :—The following were elected Ordinary Fellows :-— Messrs. W. J. Beaumont, J. W. Dunkerley, James Fleming, and J. H. Haselwood. REPORT OF THE COUNCIL FOR 1882. Fellows—The number of new Ordinary Fellows elected during the year was 40, while 15 died or resigned (12 subscribers and 3 com- pounders), giving a net increase on the year of 25 as against 28 in 1881. One Honorary Fellow has died and two have been elected, so that the list of Fellows now stands as follows:—526 Ordinary, 50 Honorary, and 83 Ex-officio, or 659 in all. Officers—The assiduous attention given by the President (Prof. P. Martin Duncan, F.R.S.) to the affairs of the Society and the effective manner in which he has presided over the meetings induced the Council to recommend a suspension of the Bye-Laws to enable him to be elected for a further term. The unanimity with which the proposal was received leaves no doubt as to the approval by the Fellows of the Council’s action in the matter. The Council regret that Mr. Stewart, after having filled the office of Secretary for ten years, has found himself obliged by the pressure of his professional engagements to resign his office. On receiving his resignation the Council unanimously resolved that they “ deeply regret Mr. Stewart’s resignation and desire to record their sense of the very valuable services rendered by him to the Society during the term of his Secretaryship.” The Annual Meeting will no doubt think it right also to warmly acknowledge Mr. Stewart’s services to the Society. Meetings—The attendance at the meetings has been fully main- tained, and the subjects on the Agenda so numerous that the time available has proved insufficient to deal with them. The Conver- sazioni have also been largely attended, but the Council regret that the impossibility of obtaining increased accommodation is at present an insuperable obstacle to their further extension. PROCEEDINGS OF THE SOCIETY. 316 SaILNNQ SVNOHT, NC { moooavg “f ‘eggy ‘yap Aawnaqeyy “yoor100 puUNo} puL poUTUTexd JUNODDW [wnUUY SuloSer0y oy, (pun [eILOMMOTT FOTN “700L Surpnyour) sjoswoy “yoo Jod oomyT, “PE “SET 1LGOL *898V5}LOJ PLOYOT “200ZT "EQQT ‘uaquiasay #8TS ‘sqUuaULpsaQuy oo ——— waunspaty, “HIVE “ST G FL &88F G FL &88F O= e17s0c * Z8ST ‘Loqueoay 4sTg Sururemer oouvpeg “ OF AZ : sol}OG §,U0ypog “Ay, 0} UoTydr1osqng “ Vane. SQ) 40 : ELeUTe jo osvysog pus ysep Ayog “ 0 G 0 oe oe . oe oe oe yoo enboyy “ 0 } T oe oe oo ee - * * oe 9ouBInsUuy Cham f “ec 0 (g I a oe “- - ra * * oe pros S]00} AOIOG “ Sout RD ~" “* ‘* °° °* s8umooTy Surueagy 48 oerog ’ 6 GT Axeyoro9g- AWUHELEY, 4g Piss Pied pue speumor “ @ rg oe eae uD utr snoouvjoostyy pue Arauoryeyg “ e ie laps CE * '* suorrsodui0g “ (1) Mths Ne Ee Se jeumor jo sosuedxgy “ 0/8 es¢° °° ott 8h ee STOTT ogee nae IL (Y aL oe oe oe oe oe oe oe sulpulg pues syood 66 0 5 a L9 * oo ee of * * ee 8007 UOISSTULp VW “ ao se apr UOISsIMMMIOH puv ‘Surytodey ‘sortepeg “ € eles ‘ ‘ ‘ ‘ ** syueuyseAuy uo ysexreyay * br Sll6 " ft eoUBpueyY pur ‘sey Guoy Ag L FL OGL ** “IST ‘toquiooogl ySTg Woy FYSRorq souR[VE OT, DENS PS “C881 (oy “6881 me “aD ‘C88T UOT CNNOOOV SHHMOSVAUL CAL “AGE PROCEEDINGS OF THE SOCIETY. 317 Library. —The Council have hitherto found it impracticable to carry out their desire to allow the books to circulate. They are, however, directing their attention to the matter, and hope to be able hereafter to announce the completion of the necessary arrangements. Donations to the Library have been received from a few only of the Fellows. The Council will be glad of further donations of suitable books. The Journal—The Journal has been continued during the past year upon substantially the same plan as in the preceding. In compliance with the desire expressed by several of the Fellows the Council sanctioned the restoration of the Bibliography, so far as it relates to either branch of Microscopy, and they understand that this arrangement has given satisfaction to the Fellows at large. Special attention has been directed to the section devoted to the pre- paration of objects, and it is believed that the portion of the Journal dealing with Microscopy is now as complete as it can be made having regard to the space available, and that the Fellows have before them a very comprehensive record of all that is being done in microscopy in all parts of the world. The question of space presents a difficulty which the Council see no prospect of being able to overcome. Mr. Crisp has informed the Council that twice the present number of pages are necessary to do only bare justice to the subjects treated of, but after giving the matter full consideration it does not appear to the Council that the limit of 1000 pages which they formerly laid down can be prudently exceeded, unless the funds placed at their disposal are considerably augmented. As notwithstanding the increase in the number printed on the commencement of the new series some of the parts are already nearly out of print the list of exchanges has been somewhat reduced, and the price of each part to non-Fellows raised to 5s. Meetine or 147TH Maron, 1883, ar Kine’s Cottzean, Stranp, W.C., James GLAISHER, Hsq., F.R.S. (Vicz-PresipENT), IN THE CHAIR. The Minutes of the Meeting of 14th February last were read and confirmed, and were signed by the Chairman. The List of Donations (exclusive of exchanges and reprints) re- ceived since the last meeting was submitted, and the thanks of the Society given to the donors. From Dippel, L.—‘ Das Mikroskop und seine Anwendung.’ 2nd ed. Pant We ssec: lee CAnteips LOD, nu eee Se beeen ee The Author. Malley, A. C.—‘ Micro-photography.’ (Ante, p.289) .. .. The Publisher. Wilder, B. G., and Gage, 8. H.—‘ Anatomical Technology as applied to the Domestic Cat.’ xxyi. and 575 pp. (130 figs.). 8vo, New York and Chicago, 1882 .. .. .. Mr. Crisp. 3 Heliotype Photomicrographs of Mosses Buje Bhan atau wate Led Ex Ob Meera. SORSlicesronG Oldy Gc cae ae lesen cen) chen ie Mr. Hanks. 1 Slide of Diatomaceous deposit from Barbadoes .. .... Dr, Rae. 318 PROCEEDINGS OF THE SOCIETY. Mr. G. Massee’s letter was read by Mr. Bennett, descriptive of a slide of the germinating spores of Agaricus (Mycena) epipterygius Scop., exhibited under a Microscope in the room. “ As nothing up to the present is known respecting the germina- tion of spores belonging to the Agaricini, I forward a slide with germinating spores of Agaricus (Mycena) epipterygius Scop. ; it shows no detail, and is only corroborative of the fact that the spores have been induced to germinate. The accompanying sketch shows suc- cessive stages, drawn from germinating isolated spores of same species. Germination commences after the spores have been about twelve hours in a mixture of glycerine and water. Usually only one thread is given off from the basal (apiculate) end of the spore. This continues to grow for some distance in a straight line, after which lateral branches are given off, ending in slightly swollen tips, which are filled with granular protoplasm. Rarely threads spring from both ends or from the sides of the spores. The spores of Coprinus radiatus Fr. germinate after a few days when placed in dilute liquid manure. The germinating tubes present much the same appearance as those described above, only the tendency to form vesicles at the tips of the secondary branches is yet more marked than in Ag. epipterygius.” Prof. Bell called the attention of the Meeting to nineteen slides received from the Zoological Station at Naples, the points of which he explained. The Chairman congratulated the Meeting upon the communication made by Prof. Bell as being the first breaking of ground by their new Secretary. Mr. H. G. Hanks’ letter (State Mineralogist of San Francisco) accompanying thirty slides was read by Mr. Crisp. Dr. James Rae’s letter, accompanying a slide of diatomaceous deposit from Barbadoes, was read by Mr. Crisp. Mr. J. Mayall, junr., exhibited a new polarizing prism, con- structed after the formula devised by Prof. Silvanus P. Thompson, D.Se., by which an angle of 18° was obtained, or nearly double that of the ordinary “ Nicol” form. He believed it would be found a very practical addition to microscopical apparatus. Dr. F. C. Kier’s letter was read by Mr. Crisp, accompanying three heliotype photomicrographs of mosses, &c. “J send a copy of my paper, ‘ Genera Muscorum Macrohymenium et Phegmatodon, &c., with three heliotype microphotographs. The objects are magnified by Nachet’s objectives Nos. 1, 3, and 5, from 27 to 175 diameters. From the photographic negatives are taken positives, which are put together on the inclosed photographic plates, I. II. and III. ; from these again negatives of the same size as the PROCEEDINGS OF THE SOCIETY. 319 originals, and from these negatives the plates have been heliotyped. I am aware that the heliotypes have many faults, and I am only fully satisfied with the plate III. fig. 5. However, I should be pleased to have them presented to the Royal Microscopical Society if you think them of sufficient interest. My negatives have not all the same power of light, and this circumstance makes it difficult to obtain good prints of more from the same plate ; the double process of photo- graphing the plates—which was rendered necessary because my negative glass plates had not all the same thickness—has also tended to impair the heliotypes. That will easily be seen by comparing the plate III. fig. 5 with the inclosed plate IV., which is heliotyped direct from my negative. In the future I shall only use plate-glasses of the same thickness for my sensitive plates.” Dr. Braithwaite thought the photographs were very excellent but feared that the plates were not sharp enough. Mr. Crisp exhibited a new form of Abbe’s condenser, the mounting allowing it to be used with the smaller stands, and the diaphragm consisting only of a sliding plate pierced with four apertures of different sizes. Mr. Ingpen, in reply to a question, said there would be no diffi- culty in using this condenser with a proper rotary stage. He could not say that it would be in all respects as convenient as the larger form, but against this must be set the fact that there were many small instruments in use upon which the larger one could not be used at all. Mr. Crisp read the leading points in Prof. Thoma’s description of his microtome (see p. 298). Mr. Groves exhibited and described a new form of frog-plate. Mr. Busk’s note on Paper Cells was read. Dr. Hudson’s paper on “Five New Floseules, with a Note on Prof. Leidy’s Genera of Acyclus and Dictyophora” was read (see p. 161) and illustrated by drawings enlarged upon the board by Mr. Stewart. Mr. Crisp thought it a matter for remark that at this day five new species of such a Rotifer as Floscularia should have been found. Mr. Ingpen said that they had been obtained from quite new ~ ground near Dundee. : Prof. Bell remarked that one of the five had since been found by Mr. Bolton near Manchester. Mr. Badcock thought it ought to encourage collectors to search much more carefully in their old localities, though these, unfortu- nately, were becoming more and more reduced in consequence of encroachments. Mr. Waddington read his paper on “ The Action ‘of Tannin on the Cilia of Infusoria ” (see p. 185). 320 PROCEEDINGS OF THE SOCIETY. Mr. Crisp thought that those Fellows who saw the slide of Para- meecium exhibited by Mr. Waddington would be struck by the very extraordinary appearance it presented. Mr. Ingpen inquired if Mr. Waddington had been able to mount the Infusoria, and what medium would be likely to prove the best chemically for the purpose. Mr. Waddington thought he should prefer dense gelatine, but no doubt a great deal of washing would be required previously in order to get rid of the tannin. Mr. Badcock asked if Mr. Waddington could account for any difference between the action of the acid on the cilia of the Para- meecium and the setze of other Infusoria. Mr. Waddington said he could not explain the difference, except that possibly the sete being thicker might require a longer exposure to the action of the tannin. Mr. Stewart thought the explanation would probably be found in the difference of development of the cuticular layer which in some species was much thicker than in others; the more exposed bodies of the Paramecia would cause them to succumb almost at once to the action of the acid. Mr. Webb’s paper “On Diamond and other Jewel Lenses for the Microscope” was taken as read, The following Instruments, Objects, &c., were exhibited :— Prof. Bell:—19 slides from the Naples Zoological Station. Mr. T. Christy :—Seed of Protea cynaroides. Mr. Crisp:—(1) Abbe’s Condenser for small stands. (2) Gund- lach’s Substage Refractor. (3) Gundlach’s Symmetrical Illuminator. (4) Chevalier’s Camera Lucida for vertical Microscopes. Mr. Groves :—New Frog-plate. Messrs. How & Co. :—Pocket Lamp. Mr. G. Massee :—Germinating Spores of Agaricus (Mycena) epi- pterygius. Mr. J. Mayall, jun. :—Dr. 8. P. Thompson’s Polarizing Prism. Mr. T. Powell :—1-12th in. Oil-immersion Objective 1:47 N.A., the front being set in the usual way, without a thin plate of glass. Dr. J. Rae :—Slide of Diatomaceous deposit from Barbadoes. Mr. Waddington :—Infusoria treated with Tannin. New Fellows :—The following were elected Ordinary Fellows :— Messrs. George W. Carter, M.A., George F. Chantrell, William Saunders, and William Stanley, And as ex-officio Fellow the President for the time being of the Carlisle Microscopical Society. WartTer W. ReEeEvEs, Assist,-Secretary. ( 138) R&I BECK, MANUFACTURING OPTICIANS. 68, CORNHILL, LONDON, E.C. “1016, CHESTNUT ST., PHILADELPHIA, U.S.A > FACTORY: LISTER WORKS, HOLLOWAY, LONDON, N. ‘MICROSCOPES, MICROSCOPE OBJECT-GLASSES, PATHOLOGICAL AND PHYSIOLOGICAL PREPARATIONS, — “Materials and Instruments for Mounting - Objects, and for Students’ Use. | ILLUSTRATED CATALOGUES AND 2 "DESCRIPTIVE PAMPHLETS Be Of the Cheaper Forms of Microscopes forwarded upon fo | | EephoneT to P68, CORNHILL, LONDON, E.C. ( 14 ) JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY, Containing its Crangactions and Proceedings, AND A SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY (principally Invertebrata and Cryptogamia), MIOROSOOPY, &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.So., F, Jerrrry Brut, M.A, Lecturer on Botany at St. Thomas's Hospital, | Professor of Comparative Anatomy in King’s College, 8. O. Riptey, M.A., of the British Museum, and JonN Maya, Jun., FELLOWS OF THE SOCIETY. Tus Journal is published bi-monthly, on the second Wednesday of the months of February, April, June, August, October, and December. It varies in size, according to convenience, but does not contain less than 9 sheets (144 pp.) with Plates and Woodcuts as required. The price to non-Fellows is 5s. per Number. The Journal comprises: (1.) The TRANSACTIONS and the ProcEEDINGs of the Society: being the Papers read and Reports of the business trans- acted at the Meetings of the Society, including any observations or discussions on the subjects brought forward. (2.) Summary of CurRENT RESEARCHES relating to ZOOLOGY and Borany (principally Invertebrata and Oryptogamia, with the Embryology and Histology of the higher Animals and Plants), and Microscopy (properly so called): being abstracts of or extracts from the more important of the ~ articles relating to the above subjects contained in the various British and Foreign Journals, Transactions, &c., from time to time added to the Library. Authors of Papers printed in the Transactions are entitled to 20 copies of their communications gratis. Extra copies can be had at the price of 12s. 6d. per half-sheet of 8 pages, or less, including cover, for a minimum co number of 100 copies, and 6s. per 100 plates, if plain. Prepayment by — P.0.0. is requested. All communications as to the Journal should be addressed to the : . fe Editor, Royal Microscopical Society, King’s College, Strand, W.C. — Published for the Society by WILLIAMS AND NORGATE, LONDON AND EDINBURGH, ( 15 ) FIESPERVUS LAMP, WITH EXTINGUISHER. EQUAL TO 45 CANDLES. Prize Medals—PARIS, THREE MEDALS, 1878. MANUFACTURED BY JONES & WILLIS, Patentees, 43, Great Russell Street, and 260, Enston Road, London, and Temple Row, Birmingham, The most brilliant-and economical mode of illumination adapted to public and domestic use. There is no lamp comparable to it for brilliantly giving three beautiful and vigorous flames of light. ‘he wicks being in a triangular form, each wick is supplied with a separate thumb-scr ew, by which it can be either elevated or depressed. The illuminating power is 45 Candles, and the consumption of oil less in pro- portion than the Duplex, or any other Paraffine Lamp. THIS‘LAMP, SUITABLE FOR MICROSCOPISTS, CAN BE SUPPLIED ON A LOWER STAND. Show-Reoms: 43, GREAT RUSSELL STREET, W.C. Works: 260, EUSTON ROAD, N.W. W. EMIL BOECKER, a MANUFACTURING OPTICIAN, WETZLAR, GERMANY, SENDS GRATIS HIS CATALOGUE OF MICROSCOPES, OBJECTIVES, MICROTOMES, AND APPARATUS FOR SCIENTIFIC RESEARCH. eee DAAALZS ‘Hein. Boecker's Microscopical Institute, at Wetzlar, Germany, SUPPLIES. MICROSCOPICAL PREPARATIONS “In all branches of Natural History. A Large Selection of Injections, Stained Preparations, Insects, Crustacea, . Entozoa,; and Lower Animals; Vegetable Anatomy, Woods, Articles of Food, Algx, Mosses, Fungi, Diatoms, and Sections of Rocks and Fossils. Instruments and Appliances for Mounting, &e. Sciopticon, with addi- _ tion for using microscopic objectives. Glass Photograms. ‘ Catalogue No. =. Gratis and, Post-free. " PREPARER OF MICROSCOPIO OBJECTS, -Late of 80, Russell Road, Seven Sisters’ Road, London, W., HAS REMOVED TO "FERNDALE, BATH ROAD, WOKING STATION, SURREY. Ready this day, with Tiluseritions: Crown 8yo, 5s. “MICRO- -PHOTOGRAPHY ; Taoading a Description of the Wet Collodion and Gelatine:Hecutille ; Processes. By A. COWLEY MALLBY, B.A., MB., B.Cu, T.GD. LONDON: H. K. LEWIS, 136, GOWER STREET, W.C. : & THE BRITISH MOSS FLORA. SE Rae at By R, BRAITHWAITE, M.D. — eS Pant Vi. is now ay peice 43. re a (10s. 6d.) may be sent to the ‘ “Author. < ~The previous Pants, with three Plates, n may ie had from the Author, at 303, Ghanian Road, London. = 3 - * ad ( 16 ) W. WATSON & SON’S fos: NEW MICROSCOPE STAND (PATENTED), The most perfect Instrument for the employment of light at great angle of obliquity ever introduced. W. & S”’s PATENT MECHANICAL STAGE Is graduated to degrees—Rotates concentric, and will revolve completely round, with any instrument—has mechanical movements in vertical, horizontal, and oblique direetions, and is the thinnest and most perfect mechanical stage ever introduced. See description in the Royal Microscopical Journal, April and June, 1881. Illustrated Catalogue of above, and all descriptions of Microscopes and Apparatus, post free 2d. W. WATSON & SONS, 313, High Holborn, London, W.C. TO MICROSCOPISTS. PREPARATIONS OF FRESH WATER ALGZ, Including Desmiprem, DiaToMAcE®, and CEDOGONIEZ ; also Funai, Mosszs, &c., showing well their Structural Development and Mode of Reproduction, 15s. per doz. slides. A few very good sets of Opaque LicreEns, suitable for low powers with the Binocular. These will have especial interest to the Student, showing the true character of the thallus, its colour and mode of growth, and as type specimens from which Herbaria may be named will be invaluable. Arpty: W. JOSHUA, F.L.S., CIRENCESTER. b. New and Second-hand Microscopes, Objectives, and, Accessories. A Large Assortment by Ross, Beck, Couinys, Swrrt, and other first-class Makers, on Sale, at a GREAT REDUCTION IN PRICE. MIGROSCOPICAL OBJECTS in great variety. Spécialité. PHysiotocicaL and PATHOLOGICAL TISSUES. A choice variety of prepared Physiological Sections ready for Mounting. PHOTOGRAPHIC LENSES, CAMERAS, and APPARATUS, by Ross, DALLMEYER, and all other esteemed Makers. Largest, Cheapest, and Best Stock in London. New Caratocues Post Free. 2 HUNTER & SANDS, 20, CRANBOURN STREET, LONDON. LIVING SPECIMENS FOR THE MICROSCOPE. THOMAS BOLTON, 57, Newhall Street, Birmingham. SPECIMEN TUBE, ONE SHILLING. A Sertes of TWENTY-sIx TuBEs in course of Six Munths (or as required) for a SUBSCRIPTION, in advance, of £1 1s. ; Portfolio of Drawings, Eight Parts, One Shilling each. Hints on the Preservation of Living Objects, and their Examination under the Microscope, 3d. UNMOUNTED OBJECTS FOR THE MICROSCOPE. PREPARED FOR MOUNTING, WITH INSTRUCTIONS, Will be ready immediately— Series D*—24 Australian Zoophytes. Series E*—12 Palates of Mollusca. Series F*—24 Mosses and Hepatics. . PRICE 2s. EACH SERIES, POST-FREB, 2s. 1d, Brown Cement, the best for Microscopic Work, post-free, 1s. 3d. Every requisite for Microscopic work. ize oe EDWARD WARD, 29, BURLINGTON STREET, OXFORD ROAD, MANCHESTER. MIiCRO-PETROLOGY. A Large Series of Rock Sections, comprising Anamesite, Aplite, Basalt, Diabas Diorite, Dolerite, Elvans, Gabbro, Gneiss, Granite, Granulite, Lava, Liparite, Napoleonite, Neppelirite, Obsidian, Pikrite, Porphyry, Phonolite, _ Quartzite, Rhyolite, Syenite, Tachylite, &c., 1s. 6d. and 2s. each. Sections of Organic Rocks, showing Foraminifera, Sponge Structure, Corals, Shells, THOMAS D. RUSSELL, 48, Essex Street, Strand, W.C Ph hae Ra Ue, Fae Oey et See ae ( W7 ) yy International Exhibition Prize Medals and Awards, 1851, 1855, 1862, 1873, 1878; and _ The Imperial Austrian Francis Joseph Order, for Excellence and Cheapness. - M. PILLISCHER’S NEW MICROSCOPE, “THE INTERNATIONAL,” - Is furnished with B and C Eye-pieces; -a 5-8 and 1-7 Object-glasses of high defining ae penetrating quality, combining (by a draw-tube) a series of eight different powers, from 50 to 420 diameters ; bull’s-eye con- denser; revolving diaphragm; pair of tweezers ; plate- Els su and thin poses. glare, and a well-made mahogany box, 10 by 6 by 4, with lock and key... .. Price £7 10s. With the addition of A Eye-piece, 14 or 2 in. Object-glass, Palatine epieta aan Selenite, and a Camera Lucida >. —.. . Price £10 10s. _ And all the Apparatus and ‘Accessories, as described above, with the addition of a D Eye-piece-and a 1-9 Object-glass, giving a series of twenty- ene PeECUINE powers, from 15 to 1000 diameters .. . Price £14 Os. A Glass Stage, to prevent the instrument from being affected: byt the use of corrosive Sunes to any of the above instruments, extra .. . 12s. 6d. a Illustrated Descriptive Catalogue on application to ; ss, NEW BOND STREET, LONDON, Ww. MICROSCOPICAL SPECIALITIES, ILLUSTRATING THE STRUCTURE, GROWTH, AND REPRODUCTION OF PLANTS. - §PECIAL EDUCATIONAL SETS, illustrating Sachs’ and Thomé’s Text-Books of Botany, the preparations being copies of figures in those works. A large assortment of miscellaneous Botanical Objects. Test Diatoms mounted in Monobromide of Naphthaline. Chas. V. Smith, Carmarthen. SPECIAT NOTICE. POWELL AND LEALAND’S NEW OIL IMMERSION CONDENSER ean be adapted to any Microscope, and resolves all the most difficult test objects—price Two Guineas. -_._ MIGROSCOPES from £11 11s. to £200. The £11 lis. Instrument consists of l-inch and. 23-inch Object-glasses, with Apertures of 30 and 95 deg. respectively, coarse and fine Adj ustment, Glass Stage and Bull’s-eye ondetes, fitted in mahogany case, and is most suitable for Students, Brewers, &e. _ WATER AND OIL IMMERSION LENSES. Manufactory : 170, EUSTON ROAD, LONDON, N.W. CHAS. COLLINS’ : HISTO LOGICAL MICROSCOPE, With 1l-inch and 1-inch Objectives of splendid Definition, Eye-piece, and Case, £5 10s. Full particulars free per post. é 3 Harley Binocular Microscopes, Dissecting Microscopes, Lamps, Objectives, Thin Glass Slips, Mediums, and every requisite for the Study, THIRTY-SIX. PAGE ILLUSTRATED CATALOGUE ON APPLICATION. ss @HARLES COLLINS, 157, Great Portland Street, London, W. e WP, Conuins’ Science. Book Depdt, adjoining the above, Catalogue on application. F. E. BECKER & CO’S PRICE LIST OF MICROSCOPIC REAGENTS AND SUNDRIES (Among the former, Stains for Bacillus Tuberculosis and all the latest novelties for Staining) will be sent post-free on application to— F. E. BECKER & CO., 34, Mammen Lanz, Covent GarpEN, Lonpon, W.C. MICROSCOPTOC OBIHCTS. Classified Catalogue. NEW EDITION FOR 1880. Post Free and Gratis. Specimens of the highest attainable perfection in every branch of Microscopy. New and Rare Diatomacee. Test and Binocular Objects. Moller’s Typen Plattes. Microscopes, Achromatic Objectives, and all Materials and Instruments for Mounting. EDMUND WHEELER, 488, Tollington Road, Holloway, London, N. NATURAL HISTORY AND GENERAL SCIENCE. THE LARGEST COLLECTION OF SECOND-HAND WORKS RELATING TO THE ABOVE. CATALOGUES TO BE HAD OF JOHN WHELDON, 58, Great Queen Street, London, W.C. A new Zoological List will be published shortly, post-free Three Stamps. Swit T & SON Are now adapting to their ‘* Challenge ”’ and other Microscopes, A NEW THIN MECHANICAL STAGE AND PATENT COARSE AND FINE ADJUSTMENTS, Also SWINGING SUBSTAGE RADIAL ILLUMINATOR, as well as all the latest Improvements and Additions to the Microscope. Catalogue fully Illustrated, and Circular, containing particulars of the above, by post for six stamps, or mailed abroad free. UNIVERSITY OPTICAL WORKS, 81, TOTTENHAM COURT ROAD, LONDON, W.C. (formerly of 48, University Street). NOW PUBLISHING. STUDIES IN MICROSCOPICAL SCIENCE. Edited by ARTHUR OC. COLE, F.R.M.S., &., assisted by several Eminent Specialists. A Weexty Perropioat for the use of Students, Teachers, Professors, and the Medical Profession, and others interested in the progress of the Natural Sciences, Each Number is illustrated and accompanied by— — (1) A Microscopical preparation of the highest class and most perfect finish; (2) A description of the Speci- . men, the methods of its preparation as a means of Study, the literature concerning it, &c.; (3) A-Chromo- lithographed, Photographed, or Engraved drawing or diagram of the Object, in the execution of which Scientific accuracy and artistic detail are specially observed. The terms of subscription, payable strictly in advance, including Postage, are—In Great Britain, Quarterly, * 2 1l. 4s,; Half-yearly, 21. 4s.; Yearly, 41. 4s. Abroad, to Countries within Postal Union, Quarterly, 11. 6s.6¢; Half-yearly, 21. 8s.; Yearly, 4l. 12s. 6d. Those desirous of receiving a smaller number of Specimens, and Fortnightly, may, for 21. 28. a year, receive either the series of 26 HistorocicAL PREPARATIONS or the 26 _ BoranicaL and PerroLocicar Sections, together with their accompanying essays and illustrations. (Abroad this Subscription will be 21. 6s. 6d.) Subscriptions to the Editor, Mr, A. C. Corx, St. Domingo House, Oxford Gardens, London, W. JAMES HOW & CO... SUCCESSORS TO GEO. KNIGHT & SONS, ‘ 73, FARRINGDON ST. (late of 2, Foster Lane, and 5, St. Bride St). HOW'S MICROSCOPE LAMP. THE MINIATURE MICROSCOPE LAMP, = 5 mo UG x HOW’S STUDENTS’ MICROSCOPE, £5 5s. THE POPULAR BINOCULAR MICROSCOPE, £12 12s, Rock SECTIONS AND OTHER Microscoric OxsEcTs. Z eet = ee 3 ( 19 ) Douncit Medal and Highest Award, Great Exhibition, London, 1851. Gold Medal, Paris Exposition, 1867. Medal and Highest Award, Exhibition, London, 1862. s ‘Medal and Diploma, Centennial Exhibition, Philadelphia, 1876. : Medal and Diploma, Antwerp, 1878. Gold Medal and Diploma, Paris Exposition, 1878. Medal, Highest Award, Sydney, 1879. ” MANUFACTURING . OPTICIANS, 112, NEW BOND STREET (FACTORY, BROOK STREET), LONDON, W. “MICROSCOPES, : OBJECT-GLASSES, APPARATUS, ‘MICROSCOPIC PREPARATIONS. IN VW DESORIPTIY: CATALOGUE on APPLICATION TO Z ROSS & CO; on 1 2, NEW BOND STREET, W. Po “(One door from Brook Street, "REMOVED FROM. 164, NEW BOND STREET, ss BSTABIISEZED 1680. a tees THE ROYAL MICROSCOPICAL SOCIETY. (Founded in 1839. Incorporated by Royal Charter in 1866.) The Society was established for the communication and discussion — of observations and discoveries (1) tending to improvements in the con-~ struction and mode of application of the Microscope, or (2) relating to Biological or other subjects of Microscopical Research. 4 It consists of Ordinary, Honorary, and Ex-officio Fellows. 3 Ordinary Fellows are elected on a Certificate of Recommendation — signed by three Fellows, stating the names, residence, description, &c., of — the Candidate, of whom one of the proposers must have personal know- ~ ledge. The Certificate is read at a Monthly Meeting, and the Candidate — balloted for at the succeeding Meeting. The Annual Subscription is 2/. 2s., payable in advance on election, and subsequently on Ist January annually, with an Entrance Fee of 21, 28. Future payments of the former may be compounded for at any time for 811. 10s. Fellows elected at a meeting subsequent to that in February are — only called upon for a proportionate part of the first year’s subscription, — and Fellows absent from the United Kingdom for a year, or permanently — residing abroad, are exempt from one-half the subscription during absence. Honorary Fellows (limited to 50), consisting of persons eminent — in Microscopical or Biological Science, are elected on the recommendation — of three Fellows and the approval of the Council. 4 Ex-officio Fellows (limited to 100) consist-of the Presidents for : the time being of such Societies at home and abroad as the Council may recommend and a'Monthly Meeting approve. They are entitled to receive — the Society’s Publications, and to exercise all other privileges of Fellows, except voting, but are not required to pay any Entrance Fee or Annual | Subscription. The Council, in whom the management of the affairs of the Society. . is vested, is elected ‘annually, and is composed of the President, four Vice- Presidents, Treasurer, two Secretaries, and twelve other Fellows. ee The Meetings are held on the second Wednesday in each month, — from October to June, in the Society’s Library at King’s College, Strand, — W.C. (commencing at 8 p.m.) Visitors are admitted by the introduction of Fellows. x In each Session two additional evenings are devoted to the exhibitiot of Instruments, Apparatus, and Objects of novelty or interest relating the Microscope or the subjects of Microscopical Research. The Journal, containing the Transactions and Proceedings of. Society, with a Summary of Current Researches relating to Zoology : Botany ee Invertebrata and Cryptogamia), Microscopy, &c., 18 published bi-monthly, and is forwarded gratis to all Ordinary and Ex- officio Fellows residing in countries within the Postal Union. $i: The Library, with the Instruments, Apparatus, and Oabi Objects, is open for the use of Fellows on Mondays, Tuesdays, Thur: and Fridays, from 11 a.m. to 4 p.m, and on Wednesdays from 7 to 1 It is closed during August. " Forms of proposal for Fellowship, and any further information, may be obtai: application to the Secretaries, or Assistant-Secre at the Library of the “oe College, Strand, W.C. : ie es ie AT ‘The Journal is issued on the second Wednesday o ef February, April, June, August, October, and December. — fAA e MAS Yat _ Ser. II. To Non-Fellows, ea IIT. Part 3.} JUNE, 1883. | Reena b JOURNAL OF THE a ROYAL MICROSCOPICAL SOCIETY; CONTAINING ITS TRANSACTIONS AND PROCEEDINGS, AND A SUMMARY OF CURRENT RESEARCHES RELATING TO ZOoOLoGyT AND BOTANYDT (principally Invertebrata and Cryptogamia), MICROSCOPY, Sc. | Edited by 3 FRANK CRISP, LL.B., B.A., Oné of the Secretaries of the Society a a Vice-President and Treasurer of the Linnean Society of London ; WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND ‘ we WwW, ‘BENNETT, M. A, B.8c., F, JEFFREY BELL, M.A.,, Lecturer on Botany at St, Thomas's Hospital, Professor of Comparative Anatomy in King’s Ccllege, ae O. RIDLEY, M.A., of the British Museum, asp JOHN MAYALL, Jon., _ FELLOWS OF THE SOCIETY, WILLIAMS & NORGATE, | HEV LONDON AND EDINBURGH. ZAG | RIN TED y WM, CLOWES AND SONS, LIMITED,] [STAMFORD STREET AND CHARING CROSS. Ea att FP AG Tae ca i a4 " VITIL—Txue Contivation AND AND OTHERS .. a es ee oe ee JOURNAL OF. THE ROYAL MICROSCOPICAL SOCIETY. Ser. 2.—Vo.u. III. PART 38. (JUNE, 1883.) CONTENTS. ——10:9200— TRANSAOTIONS OF THE SoormTy— Lire-History oF THE RimnGwoRM Fonevus (Trichophyton tonsurans). By Maleolm Morris, F.R.C.S. Ed., and G. ©. Henderson, M.D., M.R.C.P. (PTBLG NAT) ie Sissi aie ve a ss TX.—On A Portaste Form oF Ma AND ened R. L. Maddox, M.D., Hon. F.R.M.S. (Figs. 58 and 59) By Summary or Current RESEARCHES RELATING TO ZooLoGy AND Borany (PRINCIPALLY INVERTEBRATA AND Cryprocamia), Mroro- scopy, &c., INCLUDING OrigINAL CoMMUNICATIONS FROM F'ELLOWS ZOoLoGy. Mesoblast of Vertebrata : Inversion of Blastodermic Layers é in Rat ‘and “Mouse Spermatozoon of the Newt .. .. peavi rere Development of the Red Blood-corpuscles .. Beat eG Origin and Destiny of Fat-cells.. 1. sc ue news Embryology of the Milk-glands .. «se ee ae Caudal End of Vertebrate Embryos ne serene Influences which Determine Sex in the Embryo Sense of Direction in Animals .. .. ve Cerebral Homologies in Vertebrates and Invertebrates “is Apparently New Animal Type Set erat i adherens) .. Chlorophyll of Animals .. aE ep an wey te eh Sia.e Division of Lower Invertebrates. eee cask epee toereates Chromatophores of Cephalopoda... ee uw awe Deep-Sea Solenoconcha .. Pests: Vascular System of Naiadz and, Mytilidee Sees vel Generative Organs of the Oyster 44 +s se a Development of Ova in Ascidians .. ++ ae as oo Structure of Ovary of Phallusiad# .. ue ae Embryonic Development of Salpide.. — .. ee Anatomy and Histology of Brachiopoda Testicardinta.. ‘Early Developmental Stages'of Ovum in Insecta .. .. Innervation of the Respiratory Mechanism in Insects .. Histology of Insect ig iene Ke eh he eee oes Flight of Insects . PALO, Locomotion of Insects on Vertical Glass Surfaces ae tes Salivary and Olfactory Organs of Bees .. 1 we ve -Mimicry of Humming-birds by Moths .. «1 as us Systematic Position of the Archipolypoda .. 4s Anatomy and Development of Peripatus Rogereala dor ee New Species of Polydesmus with Byes .. os Ca elli dx oo se *e ee oy Coloration of Idotea tricuspidata Me aah ae ae tee PAGE 329 388 (3) _Annelids of the Canary Islands... Anatomy and Histology of Ter: ebellides Strocmit Exogone gemmifera’ .. Bh Structure and, Development of Phoronis .. Development of Borlasia vivipara .. 1. New Human Cestode—Ligula Mansont .. Psolus and its Allies .. SAE Hy Perivisceral Fluid of the Sea-Urehin —.. S . Hudiocrinus.. -. Bee eee ~~! Aretic and Antarctic Crinoids BARA Classification of the Comatule .. .. Origin of the Spermatozoa in Meduse Bndodermal Nervous System in Hydroids Dewelopment of the Tentacles of Hydra Vosmaer’s Porifera ». Bin Sao eis abet Nee Fresh-water Sponges of Bussia . Lp ree A * Biitschli’s Protozoa. Summary or Current Reszarouns, &¢.—continued. Flagellaie Infusorian, an Ectoparasite of Fishes - Gigantic Actinesphzrium Hichhornii .. Dimorphism of Foraminifera. §.: +. 4s Vampyrella se ahs a New Moneron Hematozoa of Fishes... .. + Borany. Nature of tI the Process of Fertilization .. Pollination of Aracce.. 1. 1. es Pollen-tubes .° ~.. i Autoxidation in Living Vegetabie Cells zs Structure of the Bundle-sheath 1... +s Buried Leaf-buds .. BiG eh Structure of the Wood of Conifers ee Medullary Rays of Conifers and Dicotyledons. Pengo Value of the Number and. ee Conifers sd A 6 Achenial Hatrs and Fibres of Composite . pie ak 1s Influence of Sunny and Shaded Localities on the Deva lopment of Leaves . Crystals of Calcium oxalate in the Cell-wall _ ‘Position of Leaves in respect to pide Photepinasty Of MECOUERT Ea a entail esa Sra Movements of Leaves and Brute as Movements of Water in Plants . ay as Distribution of Tinergy in the Cilorophyl-spectruan Colour and Assimilation. .. .. AH of Liquids in Living Vegetable Tissue ence of Electricity on Vegetation .. «, ste Prothallium of Equisetum eee ear ‘Reproductive Organs of Pilularia 660.6 Aerial Branches of Psilotum ..0 1.0 1s Underground Branches of Psilotum ... .. ~* Male Inflorescence of Muscinee =». sss > Antherididim of Hepatior (x. 215 vo ee es Monograph of Characee .. .. +. >. P42) Physvology-of Pungi ... 4660s av ~ Fungus Parasitic on Sponges. a bie Glycogen in the Mucorint 1.0 1.0 se oa Hetereecism of the Uredines ., 4. ss ee. Of: the Blood Wie eni en ies Distribution of Water in the Se id Parti. of Plants ' Exoretion of Water from. Leaves. us ss l Trichomatic Origin and Hormation Of 201 Zine: : Cystotths 4p Permeability of Wood to Water... ., es * Formation of Starch out of Sugar | Occurrence of Allantoin and Asparagin in Young Lewes Bh Cholesterin, Phytosterin, Paracholesterin, &e. .. ee eer of Submerged Parts.of Plants... of the “Medul lary y Ba ays ; 396 396 397 398 399 ee Silas Summary or Current Resuarcues, &c.—continued. New Species of Micrococcus _. tot ee Se Leena Influence of Light on the Development of ‘Bacteria... a8 it os hia teagan meas Bacteria connected genetically with an Alga .. a Bacterial investigation of ede Gaslight, and the light of. Eason’ 8 ‘Lamp ; Microbia of Marine Fish .. bib Seine Movements of Minute Particles tn: Air and Water vcs. ae Wiad ee oe Miquel’s < Living Organisms of the Sees ee ite Caer tee Oh ee Reproductive Organs of Lichens .. ~. Ban oie nee aor aes Chromatophores of Algae +s ss ee eet ne ee a we we Phycochromacez .. San SORE. Sealy Saal eee rae Spee peieaves Bangiacex of the Gulf of Ne aples Bosna.) Lav op 00-inch) AO pS Spherozyga Jacobi. ET re tage Algoid Structures in the Coal of Central Russi. 0 eee zs cpu maa cy of 8 vee radians by Caustic Potash .. .. ‘s+ es» Jew Xanthidium.. a0 da i cael pee ea Fiisiee of Diatoms in the Jutland “ Cement-stone” =... sae ae Motion of Diatoms 44° 2s ee ae es ne we te be ee aw Pfitzer’s Diatomaces i. se sce an be se he ee ee nk) ne ae Microscopy. Bertrand’s Petrological Microscope (Figs. 60-62) .._.. 3 Be Fase’s Portable Binocular Dissecting and Mounting Microscope (Fie. 68)... Klénne and Miiller’s and Seibert’s Demonstration Tirta (Pes, 64 and 65).. res Sy Sri Seibert’s Travelling Microscope (Fig. 66). eo eee ee Elénne and Miiller’s “‘ Pendulum Stage” (Figs. 67 and 68) Ope an Leiter and Mikulic?s Gastroscopes Bigs. | 69 oF 70). shes Cobweb Micrometers.. Se ces ee eget Cabs Chevalier’s Camera Lucida (Fig. 71) Mais ata REPRE te ee IT Sie oe Grunow’s Camera Lucida (Fig. 72) TRIER TE Holle’s Drawing Apparatus. va: Ls Hi a BR at FS Ltt at is] V ERS 1 le Ril Lt}. RAR ae a) & ber Cy s, | | GRASS, Poets pee ce ord EE Ir, et) Conversion of British and Metric Measures. C1.) Linzat. Micronuttimetres, gc., into Inches, &c. a * ios. ~ "| mm. ins. mn, ins, 1 -000039{ 1 -039870| 51 — 2°007892 2 -000079) 8 “078741 | 52 2047262 8 -000118| 383. *118111 | 538 2086633 4 -000157| 4 157482 | 54. 2-126003 5 000197) 5 -196852| 55 2165374 6 --000236| .6 936993 | 56- 2°204744 @. :000276| 7 975593 | 57 2°244115 8 -000315| 8 -314963| 58 2°283485 9 §-000354 9 354334 | 59 2°329855 10. -000394 | 10 (1em.) *393704| 60 (6 cm.) 2°362226 11. -000483 | 11 433075 |. 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" SZ6FS~ 6~ 9TGEST- 80. 6SFEZL- 8 FIOLFL- TL Le GOZSSF- 8-5 LEGSSS-F LO. 9Z080T- Vs “sorqT[I}U0d SLILGP He oi LE LE6L88- 90- #6260. 9 FLOTES 6 9. BGIOOE Seve L29F 4 SF668S-S C0. | @9TLLO- ¢ LISS6T-8 c. LCTEOS 5 Oe 2 . SE616S-3 0. 6ZL190- ? 6F9FES-9 F- GOIFES- ae 2 696846: T er G0e L6Z9F0- $ L86S16-F g: OLOSST- ag 6L6663-T 30+ C98080- j CZELLB-E ° 3: TCOZBI- o 686LF9- 10- BSFSLO- I Z99889-T pan i GzOI90« = I “SOUUUBADT] [TUL ‘surmas *SULUUD *SOTUUBAISIT TU *SOAgTTE [LU ‘sul "quo © “Suzy ‘qno © *BOIg TT [LUE ‘of Ssomumabypyg ogre “of ‘sui of ‘summa ome “oh ‘soumunsboj Op ‘saupiueen ogua “aL Ssayoug o2qng- Of ‘soyour ann) ome “OH “Soa “~HDITM (§) "KLIOVEVQ) CR) ‘ponuyju0o—SOIMSBOY OIIJOWL PUB YSIFIIg JO WoIs1oAMOH CAoo Seales. Angles, Cent. a ahaa (1.) Rerraorryn Inpices. fe) 100 2120 Linseed oil (sp. gr. *932) Oil of turpentine (sp: gr. +885) Alcohol || Sea water Pure water = Air | S (3.) Povarizina Axcis, 98 208-4 || Diamond - 6 204°8 94 901°2 p Hcepuores 92° 197°6 Bisulphide of carbon 90 194°0 || Flint glass 88 190-4 86 186-8 || Crtown glass 84 183°2 || Rock salt : Be mee Canada balsam _ "8 172°4 Linseed oil (sp. gr. *932) = tees Oil of turpentine (sp. gr. 885) 72. 161-6 || Alcohol a 158:0 || Sea water 154°4 66 150-8 Pere sees 64 147-2 || Air (at 0° C. 760 mm.) 62 143°6 ra a6) (2.) Dispersive Powers. Pe aes : Diamond 52° 125-6- || Phosphorus 50 122-0 sree 48 1184 os of carbon 46 114°8 Flin¢ glass 35 : oe Crown glass 40 Aen Rock salt 38 100°4 Canada balsam 8 “2 24 - Diamond |) Phosphorus -Bisulphide of carbon Flint glass. ||| Crown glass “|| Rock salt -g |) Canada balsam Linseed oil (sp .2r. 932) Oil of turpentine (sp. gr. *886) “Aleohol — ; Sea water - - _ Pure water Ais gee \ a S198 OO Se He GORA? i Hy Sih —, PAYS . OO ns Corresponding Degrees in the || IV. Refractive Indices, Dispersive Fahrenheit and Centigrade Powers, and Polarizing [Exact data for these tables ‘are at "present wanting.) ( 10) V. Table of Magnifying Powers. tee | ’ EYE-PIECES. me Beck's 2, : [poweirsi, al Powell’s 3,} Ross’s C. | Beck’s 3. oe aad bas me Powell’s 5.4 Ross’s FL Ross’s A, § Ross’s B, Ross’s D. erage nearly.* Pe = Foca, LENGTH, Soe o 5 m4 x 12 : = As 2. 1% 4 : . 1 S 2 in. 5 in. |. Lin. | 2in. |} Fin. | dine fin gin, | fin. 4 ps : 2 z Maeniryine Power. a s | 3 7 a — Game ee 7 | 10 | 12, | 15 | 20 | 25 80 1-408 ‘AMPLIFICATION OF OBJECTIVES AND EYE-PIECES — COMBINED. a "5 2 10 15 | 20° | - 25 30 40 50 4 214 «128 182 25 312 37k 50 623 3 eit 162 25 334] . 412 50 662 832 2 5 25 373 50 623 75 100 125.) |: 13 32 382 50 662 831 | 100 1332} 1662. 1 10 50 75 100 125 150 200 250 8| 123). .623 932 125 1561 1872 250 3122 |. 3 181} - “662 4 ~ 100 1332 | 1662}. 200 2662 | 3832 ve) 15 ee 45 1123-4.» 150 1873 | - 225 {300 375 2 20 } 100 150 200 250 300 400 500 | 25 ft 125 1872.4 250 3122)| 875 500 | . 625 2 30 ~ 150 225 300]. 875°} 450 600. | “750 |. 9 3 $33) 1662 4- 250 3232 | 4162 | . 500 6662 | ~ 8832 | 1 40 i 200 300 4 =400 500° | =. 600 800 $ 1000. . 2| 50 i 950 375 500 625 750 §-1000 $1250 2 60} 300 450 600 750 co} 1260 } 1500 a2} 70} 330 525 700 875 | 1050 4 1400 4. 1750 et 80 i} 400 600 8c0. } 1000} 1200 | 1600 } 2000. | 2} 90% 450 675. | 900 | 1125 | 1350 | 1800. § 2250} 27 3, -| 100] 500 750 j 1600 | 1290}. 1500 f 2000. f° 25007 |. See AR gD 550 €25 |. 1100 |..1375-]. 1630 | 2200 | 2750: |. “3, ~| 120-600 4 900.4 1200 | 1500 -}. 1800 } 2400 | 3000. | ~~ 21°930 9 650 4 975 4 1800 | 1625. | 1950: f 2600 | 3250, ¢ os; | 1407-700 7 1050 } 1100 | 1750 | 2100°} 2800 | +3500. | ° 3; |)150 I 750 | 1125 1500 | 1875 | 2250 | 3000} 3750 |. 1160 } ~800°4 1200 f- 1600 2000 2400. | 3200 4 4000 | : “2,170 i} 850 -§ 1275 4 1700 |} 2125 | 2550 |. 3400 bf = ope. | 180} 900.1850 f-1800° | 2250 | 2700 fF 3600 | / {1904 950° 4 1425 7 1900 |} 2875 | 2850 | 3800: -f 2; | 200 | 1000° | 1500 { 2060 |» 2500 | 8000 4 4000 | ~ +d} 250 9 1250 | 1875 4 2500 | 3125 | 3750 7 5000 § 6250. | 7 2 (800 f 1500 }- 2250 § 2000 | 3750 | 4500 4 6000 | 7500° |>-¢ q;|400 } 2009 | 3000 }~ 4000 | 5000 |. 6000 jf. 8000 § ee gs | 500. 2500 4 38750 | 5000 | 6250. | 7500 £10000 4. ,} 600 f. 3000 4 4500 | 6000-| 7400. | 9000 412090 § 150 2 800 |. 4010 pn ae AGO ne eve et a “Powell and Lealand’s No, 2 aa aa ‘and 1 Becks No. 2 and Ross f = Sine pve or. ee he peneeetvely, v less. and 7; More than the: fois sve in, this SON ; a Author. Ca) ‘Bol EHlicroscopical Society. MEETINGS FOR 1888, At 8 Pm. 1883. - Wednesday, Finca le es, 10 FEBRUARY .. Atego: 5 (Annual Meeting for Wedien of Officers and Council.) Aye Wau 8S oo ee ee ead s BRIG pt My eye sor Ra ok eee aL SPO oe RAVER Ce eee Se ee uta) SRS et he CeO PONS ee te CRS ire ase eee lO OcTOBER ee eae eek LO NovEMeMn i 3. fo cs ae oes DROMMERR eet Beas ree on ke THE “ SOCIETY” STANDARD SCREW. ; ce Tho Council have made arrangements for a further supply of Gauges and Screw-tools for-the “Socrmry” SranparD Soruw for OpsEcrivEs. The price of the set (consisting of Gauge and pair of Screw-tools) is 12s. 6d. (post free 12s. 10d.). Applications for sets should be made to the Assistant-Secretary. For an explanation of the intended use of the gauge, see Journal of the " Society, I. (1881) pp. 548-9. THE BRITISH MOSS FLORA. By R. BRAITHWAITE, M.D. yee VI. is now ready, se 4s; Subscriptions (10s. 6d.) may. be sent to the yee The Bea Parts, with three as may. be had from the ‘Author at-303, Clapham Road, London. New Edition, very much enlarged, 21s, : HOW TO WORK WITH THE MICROSCOPE. i BY LIONEL Ss. BEALE, F.RS., “TREASURER AND FORMERLY PRESIDENT OF THE ROYAL MICROSCOPICAL SOCIETY, ; : THH FIFTH EDITION. © Sheselyt bound and enlarged to 530 pages, with 100 Plates, some of which are Coloured. HARRISON AND SONS, PALIO MADIL "ADVERTISEMENTS FOR THE JOURNAL. ‘ ‘Mr Gracin BuEncows, of 75, Chanel Lane, W.C., is the authorized Agent oes Collector for Advertising Ropounts on behalf of the merges ( 12 ) CHARLES COPPOCK (LATE PARTNER WITH R. & J, BECK), 100, NEW BOND STREET, LONDON, W. OPTICIAN AND Manufacturer of Scientific Instruments, INCLUDING MICROSCOPES. ASTRONOMICAL AND OTHER TELESCOPES. STANDARD AND OTHER METEOROLOGICAL INSTRUMENTS. CLINICAL THERMOMETERS, OPERA AND FIELD GLASSES. | SURVEYING, NAUTICAL, and DRAWING INSTRUMENTS, including ARTISTS’ MATERIALS. OPHTHALMIC INSTRUMENTS. SPECTACLES AND EYE-GLASSES. READING GLASSES. HAND MAGNIFIERS. STEREQSCOPES. POCKET AND CHARM COMPASSES, &c. N.B.—AGENT For R. B. ToLLes, oF Boston, Mass., U.S.A. W. H. BuLLocn, oF CHIcAGo, ILLs., U.S.A. rae M. PRAZMOWSKI (Late HarTNack & Prazmowski), PARIS. 99 M. A. NACHET, PARis, ano JOINT AGENT FOR Dr. ZEIss, JENA. ¥ 3 OCULISTS’ PRESCRIPTIONS RECEIVE PERSONAL ATTENTION, = 100, NEW BOND STREET, LONDON, W. 64 ge a iva ao eer eh Ty shea a JOURN. R. MICR. SOC. SER.I. VOLO, PL.Via _ Red Mould of Barley. re! girs Me See Lannie mihi eee JOURN. R. MICR. SOC. SER IL VOL. a — 7 EF en Red Mould of Barley. \ & pad 1. of JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY. JUNE 1883. TRANSACTIONS OF THE SOCIETY. VII.—On the Red Mould of Barley. By Cuartes Gzrorce Marraews, F.C.S8., F.L.C. ait (Read 11th April, 1883.) PLaTes VY. anp VI. Dounrine the malting season of 1879-80, when the quality of the majority of samples of English-grown barleys was decidedly inferior, my attention was directed to the frequent occurrence of so-called “red corns” amongst the couches at a small malt-house where various samples of English barley were being worked up. Since it was evident, on a very cursory inspection, that the red corns owed their peculiar appearance to a definite mould-growth, I made search in such treatises on the moulds as were at my command, for information bearing on this mould in particular ; but was unable to find any reference to it. It then occurred to me to communicate EXPLANATION OF PLATES V. ann VI. PuatTe Y. Fic. 1—Barley corns with and without red mould. 2.—Pseudo-sporulation of red mould. 3.—Crescent spores of red mould. 4.—-Spores dividing at septa; a, 6, peculiar forms. 5.—Germinating crescent spores of red mould. 6.—Red mould as detached from the corn. ” 99 Piate VI. Fie. |.—Red mould growing as a ferment. 2.—Third sporulation of red mould. 3.—Germinating spores of red mould. 4.—Melon mould; a, submerged portion. ao is growing as a ferment. + | Ol—— a spores sprouting. Ser. 2.— Vor. III. Yo L 322 Transactions of the Society. with Dr. Chr. Hansen, of the Carlsberg Laboratory, Copenhagen, who has given much time and attention to the microscopic fungi. Dr. Hansen kindly informed me that the mould I had described to him was either Fusarium graminearum or some closely allied species; and that its life-history had not been traced. Seeing that this was the case, and feeling an interest in the matter, I endeavoured to obtain a closer knowledge of the mould by cultiva- tion on natural and artificial nutrient substances, and frequent examination under the Microscope at different stages of its growth. Where a low magnifying power was required, a combination of a Ross's B eye-piece, and 1-in. objective was used; for a more minute examination the same eye-piece and 1-5th in. objective (Ross) were employed. To the maltster the appearance of these red corns is probably not unfamiliar, though they are only seen in any quantity during the malting of inferior barleys. The mould is chiefly at the germinal end of the corn, and exhibits a conspicuous crimson colour. I will reserve further remarks on the character of the affected corns till a later part of these notes. To proceed now to the examination of the crimson-coloured matter on the exterior of the corns affected with the mould. A small quantity was detached and gently stirred into a drop of water on a glass slide, a cover-glass being then pressed on to it. On applying a high magnifying power large numbers of crescent- or spindle-shaped bodies were perceived, together with filamentary fragments, starch-granules, and amorphous matter tinted with the red colouring (see plate V. fig. 6). The question naturally arises as to the origin of this and commoner forms of mould, to which barley and other cereals, under certain conditions, fall a prey. It is well known that the air of populous districts contains various and mul- titudinous ‘particles in suspension, which are being constantly deposited on resting surfaces as dust, and it has been shown by eminent scientists, that the dust (which consists for the most part of microscopic particles) includes various organisms such as bacteria, infusoria, ferment-cells, and spores of the commoner moulds, gene- rally in a state of desiccation. An experiment was made to determine the constituents of the dust adherent to barley. A quantity of barley (about 50 gms.) was steeped ina suitable volume of water for about 12 hours, the containing vessel being occasionally well shaken ; at the end of the time and after shaking once more, the water was poured off, a little fresh water being then added, which after shaking up and separating from the barley (which was neglected), was added to the first portion and the whole put into a glass cylinder, the suspended matter being allowed to settle. After a minute or two had elapsed the liquid was poured off from the coarse particles and put intoa second cylinder, where it was allowed On the Red Mould of Barley. By C. G. Matthews. 323 to remain for a few hours, when a deposition of the finer particles in suspension took place. The deposit in each case was examined under the Microscope ; that from cylinder No. 1 showed only earthy particles, humus, and sand, and was neglected. ‘The deposit from No. 2 cylinder yielded several objects of interest, such as bacteria, infusoria, and mould spores. Among the latter were crescent spores of the red mould now under consideration. Various kinds of barley, including Saale, French, Chilian, and Californian samples, were treated as above, and yielded similar bodies, though in varying quantities. An examination of the accumulated dust under barley-heaps was also made: the greater portion consisted of earthy matter, but in addition, mould spores, infusoria, and bacteria were found similar to those obtained from barley. The washings of oats, horse-beans, and the ripe ear of wheat also yielded some or other of the organisms described. There can be little doubt, then, that in the first stage of the malting process the spores of various moulds are present in quantity in the “steep,” being introduced into the cistern with the barley, and although the greater portion may be removed on withdrawal of the steep-water, yet even if the air did not furnish fresh spores, there would be left, in all probability, sufficient to cause a mould- growth on injured or weakly corns whilst on the malting floor, other conditions being favourable thereto. In order that a thorough examination of the growing red mould might be made, it was necessary to find convenient methods of cultivation, and to this end various experiments were undertaken. The first thing tried was the crushing and moistening of the affected corns, the mass thus formed being allowed to develope the mould under a glass shade. In this way small tufts of the mould were obtained, but it appeared desirable to grow it on a larger scale, and to do this, germinating barley from the fifth day and upward out of steep was worked into a stiff paste by pestle and mortar, a little water being added to assist the operation. This paste was then put into small dishes, and a few red corns were partially imbedded in each quantity, the dishes being placed in a wire frame, resting on an ordinary china plate containing a little water, the arrangement being completed by covering with a bell-glass. Very fine silky tufts of the red mould were thus obtained from 1-2 to 3-4ths in. in height and nearly 2 inches in diameter, spread over the nourishing surface, and with no tendency, during the winter months, to invasion by the commonly occurring moulds. In each cultivation there was a considerable production of the crimson colouring matter which was diffused amongst the plasma, and the hyphe were tinged with it where they sprang from the B24 Transactions of the Society. nutrient surface, though their extremities were colourless. These growths constituted very interesting objects. Various plasmas were impregnated with the mould, the results obtained being detailed below. Crushed malt worked with water ) “oie anto a stiff paste very indifferent growth. Slices of cooked turnip and potato. . Fairly well; invasion of other moulds. », Yaw turnip and potato .. Hardly any growth. » melon -» os ‘es So Very anditferentiy Cooked meat .. [30a eee 2 Raw meat .. .. .. «.. «. Hardly any-growthk For the following microscopical observations the mould under consideration was cultivated on crushed germinating barley, the best growths being obtained with this form of nourishment. The tufts of mould, which formed in about ten days from the time of sowing, consisted of a mass of hyphe, indistinguishable as such from those of many other moulds. These hyphe gradually become interlaced, and in two or three weeks’ time, owing to their increasing weight, begin to droop and the tuft flattens “down; just at this time a kind of sporulation was observed (fig. 2). I would here make a few remarks as to the method employed for the collection and treatment of small portions of the mould- growths for microscopical observation, as some difficulty was at first experienced in removing portions from the growing mass, owing to the tendency the hyphie have to adhere persistently to each other when disturbed. After examining the growth with a low power (55 diameters), small glass hairs rounded at the ends in a Bunsen flame were used to detach portions for examination under the higher power (500 diameters). A drop of dilute alcohol was allowed to fall upon them from a small pipette, a cover-glass being gently pressed on. Dilute alcohol is preferable to water for general use, for the portion of mould under treatment has less tendency to alter its existing contour on immersion in the former than in the latter. To revert again to the sporulation shown in fig. 2, I spoke of this purposely as a kind of sporulation, for as two more methods of sporulation were observed of a true character, and seeing that in no case was the regeneration of the mould perceived from the bodies depicted as escaping from the hyphe, I have been led to regard this as an abortive sporulation, and the minute bodies as pseudo- spores. : Up to this point no crescent-shaped bodies were noticed in any of the cultures, despite the extensive production of colouring matter similar to that on the red corns. On the Red Mould of Barley. By C. G. Matthews. 325 Shortly after the flattening down of the tuft of mould a pink dust was perceived in minute patches on the whitish surtace. On examination this was found to consist of clusters of crescent- shaped spores (fig. 3), attached by their pointed ends so as to form fasces, these again being attached to the plasma by short irregular hyphe. On touching or wetting, the arrangement is at once disturbed, and the crescents falling loose, are then seen to be of varying size. The crescents are doubtless developed by sprouting at the extremities of short hyphee, developed on the flattened surface of the mould-growth, and not from spores discharged from an ascus (for as yet no kind of ascus had been seen), though observations made at a further stage in the development of the mould indicated that this in a limited way was quite possible. Sometimes the pink patches spoken of became moistened by the condensation of minute drops of water on the surface of the mould, causing a reddish-orange coloured spot to be formed consisting of a mass of the crescent bodies in a resting state. From these spores, fresh growths of the mould could be obtained by sowing on a suit- able nutrient surface. The colouring matter was found to be in the material surrounding the crescent spores, which are in most cases colourless, though sometimes they are faintly tinged with colour. The formation of these crescent- or spindle-shaped bodies thus con- stitutes a second kind of sporulation, and we may now consider the way in which they reproduce the original mould, for this they are capable of doing, thus differing from the bodies produced in the first or pseudo-sporulation. Some of the pink-dust patches or reddish-orange spots were removed and placed ina small quantity of water ; the crescent spores sink slowly to the bottom of the containing vessel, and by careful decantation can be separated from adherent matters, the water being renewed once or twice, the spores being finally left in contact with pure distilled water in a covered vessel and examined daily. Interesting changes occurred, for in the absence of nutriment, some of the spores divided at the septa (fig. 4), in some cases a short length of tube, or an abortive hypha was formed between two segments (a, a, a) or a swelling of some of the seg- ments took place (0, b) distorting the crescent. In the meantime other of the crescent spores began to throw out hyphe ; some of the segments even doing the same (fig. 5). Shortly after these observa- tions the water was poured off and the germinating spores were put on fresh plasma, when an active reproduction of the red mould shortly took place. Several growths of the mould were allowed to go on for some few weeks, and were subjected to frequent examination, remaining at the same time free from the invasion of other moulds; for on a 326 Transactions of the Society. suitable plasma the red mould is capable of holding its own for a considerable time against common species like Pendcilliwm and Mucor, excepting in the summer months, when the plasma being quickly attacked by Mycoderma vini, Mucor, or bacteria, rendered a pure cultivation of the red mould a matter of some difficulty. Afte? a time it became evident that asci or sporangia were being formed, and these eventually attained a fair size (see plate VI. fig. 2). On moistening a single ascus with water, its contents were dis- charged and the spores exhibited considerable variety in shape, though they were for the most part spherical ; some had a tendency to an elliptic form, and a few showed an incipient crescent shape. The elongated and irregular appearance of some of the spore- clusters (fig. 2) was caused by the rupture of the ascus, consequent on its coming into contact with the moisture which occasionally formed as a dew on the tufts. The spores were successfully sown on fresh plasma and gave rise to an undoubted growth of the red mould. Fig. 3 shows the germination of the spores. By a chance coincidence I was led to examine a mould: growth on a bruised portion of a Spanish melon, and was surprised to find that in several respects it resembled the red mould of barley. The first portion of the mould removed from the melon showed a quantity of crescent spores distributed amongst hyphe (aerial and submerged), some of them identical in form with those of the red mould, others showing a variation (fig. 4). Parings of the rind of a perfectly sound melon were washed with water, at the same time going gently over them with a camel’s hair brush to detach any adhering substances ; the washings were examined, and showed a quantity of crescent bodies (fig. 5), which unquestionably were capable of giving rise to a mould-growth similar to that observed on the bruised melon. This melon mould also produces the crimson colouring matter; on referring again to fig. 4, a portion of the growth (a) will be seen which I have no doubt was caused by the submerging of some of the hyphe in the juicy portion of the fruit. On exhausting the spores with pure water, as in the case of those of the red mould, their behaviour was dissimilar, for no separation into segments took place, and the sprouting was of a very limited character, the hypha terminating in a spherical or rounded cell, which in some cases sent out a bud, thus forming a pair of cells which sometimes became detached from the crescent spore (fig. 6). Distortion of the crescents occasionally ensued. ‘he mould was regenerated from the crescent spores, and allowed to grow freely for some weeks, during which time crescent spores were formed in bundles attached to the hyphe (fig. 4), no ascus On the Red Mould of Barley. By C. G. Matthews. 327 being formed. Colouring matter was produced as before. The melon mould had little or no tendency to grow on the crushed germinating barley food, whilst the barley mould in the same way declined to flourish on pieces of melon. The close likeness existing between the crescent spores of each mould is the chief point of interest—indeed, spores of each may be selected that are indis- tinguishable. In many other respects the moulds are dissimilar. Each of the two moulds described was introduced into sterilized beer-wort of specific gravity 1-057 in separate flasks, and gave rise to characteristic ferments, closely resembling each other, and re- markable for the extraordinary size of the cells. These ferments produce alcohol and carbonic acid gas, but act in a very sluggish manner, being far less active than the ferment Mucor. The re- sulting beer has a mawkish flavour resembling that produced by the ferment just mentioned. To refer again to the sprouting of the crescent spores from the melon given in fig. 6, it would appear that the spherical bodies produced are ferment-cells, and on these becoming detached and finding themselves in a suitable fluid, reproduction by budding takes place. The ferment in each case collects into leathery flocculent masses consisting of interlaced tubes similar to Mucor, and inclosing in their meshes quantities of detached cells, such as in figs. 1 and 5. To conclude with a few general remarks on the behaviour of the red mould in the “ Maltings.” The growth of the mould commences at the germinal end of the corn, and spreads towards the opposite end, the rate of growth being determined by the supply of nourishment from the interior of the corn, and this again is determined by the extent of the injury the corn has received by crushing, &c. On some corns a very slight coloration is apparent, whilst others are almost covered by a crimson paste, from which hyphe are sometimes seen spring- ing. The corns which are subsequently the worst affected are just distinguishable amongst the dry stored barley, but many others that look like “idlers” develope the mould when on the “ floors”; but it is not until they have been four or five days out of steep that their presence is observed ; from this period till the time of loading the kiln the mould grows with some rapidity. The affected corns are always such as are from various causes incapable of proper germination, having perhaps been injured by heating in the stack and sprouting, or by being split or crushed during the threshing, and are generally discoloured, misshapen, and indicate by their appearance that little is to be expected of them. Occa- sionally in such corns an abortive growth takes place, one or more sickly brownish-looking rootlets may appear whilst the acrospire remains inactive ; in others the reverse occurs, the acrospire growing to some length, the rootlets not appearing, having been shrivelled 328 Transactions of the Society. up during a premature sprouting. Such are the corns which are found with this particular mould developed upon them. The mould is never seen on a healthy, germinating, perfect corn, and this is no doubt equally the case where the commoner moulds, e. g. Penicillium and Mucor are concerned, for although these, especially the former, spread at times with some rapidity amongst the couches, it is only when the corns are exposed to abnormal conditions of temperature causing a reduction in their vitality. It will be understood from the foregoing remarks that the red mould does not spread from corn to corn excepting where injured corns lie for some time in contact; this is probably owing to the fact that the spores are not disseminated like those of the common moulds, owing to their greater weight and their tendency to remain adherent to the original mould-growth. Corns seriously affected with the mould may be distinguished among finished malt, being rendered conspicuous by the colouring matter still adherent tothem. Mould- spores can have little or no influence of themselves in the mashing process, and are undoubtedly destroyed during the boiling in the wort-copper. Nevertheless, malt exhibiting red corns must be of an inferior quality, having been prepared from an indifferent sample of barley, besides which the mould-growth will have acted in a prejudicial manner on the constituents of the corn, using up extractible matters and imparting peculiarity of flavour. I have left the consideration of the colouring matter produced by this and other moulds to the light of future experiment. ‘ JOURN.R. MICR.SOC. SER ILVOL.ULPL Vi. ~ 2 ee ' A he eat 4 Ringworm Fungus | Trichophyton tonsurans) — NE ils eat cae miami aide (i Lig aan ( 329 ) VIII.—The Cultivation and Life-History of the Ringworm Fungus (Trichophyton tonsurans). By Matcorm Morris, F.R.CS. Ed., and G. C. Henprrson, M.D., M.R.C.P. (Read 11th Apri’, 1883.) Puate VII. Tue life-history of the ringworm fungus, first discovered by Malmsten and Gruby in 1844, and its exact botanical position, still remain a matter of uncertainty. Some observers hold strongly to the belief that this fungus is a distinct species, whilst others consider it merely a variety of one of the commoner Hyphomycetes ; and these again hold different opinions, ascribing it variously to Penicillium, Aspergillus, Oidium, and Mucor. We commenced the present investigation without any bias for or against any of these views, and have been led to our conclusions by the results of our experiments alone. Kuperiment 1. Cell cultivation with aqueous humour.—The aqueous humour was placed on the under surface of the cover-glass, which formed the top of a putty cell. In some cells an air-passage was left, while others were closed. A small quantity of distilled water was placed at the bottom of each cell to maintain the moisture of the chamber. Hairs were removed from typical patches of untreated ring- worm and were inclosed in a glass tube. One hair was floated on a drop of aqueous humour in each cell. Spores adhering to the hair and root sheath were seen under the Microscope to be those of typical ringworm. Placed in the incubator at a temperature of 23° C., in 24 hours the two preparations with air-passages were completely dried up. The spores showed no signs of growth, and were surrounded with masses of bacteria and micrococci. In the closed cells, the spores were swollen, and some of them presented minute protrusions from the sides, as if due to commencing growth. As in the open Specimens bacteria were abundant. After 48 hours the pro- cesses had become distinct and were about twice the length of the spores. Subsequent examination showed no further develop- ment, the bacteria present apparently preventing growth. Haperiment 2. Cell cultivation with vitreous humour.— Vitreous humour was used in the place of the aqueous, the hairs being taken from the same case, and the experiments were similarly conducted. Five in all, one open and four closed. Placed in the incubator at 23° C., swelling and budding of spores took place _ within 48 hours, and in 80 hours buds had grown out into distinct mycelial filaments. The fluid, however, contained very numerous micrococci, bacilli, and some triple phosphate crystals, which obscured Ser. 2—Vor. TIT. ¥—2 330 Transactions of the Society. the growth. No further growth took place during the eight days in which the preparations were under observation. Experiment 3. Cell cultivation with Gelatine peptone— Gelatine peptone, as suggested by Koch, but with a larger portion of gelatine, was used in the place of aqueous and vitreous humours, as being more easily obtained, sterilized, and more uniformly solid. A small portion of the jelly was cut out and placed on a cover-glass with a ringworm hair on its surface. The cover-glass was then inverted so as to form the roof of a putty cell, air being admitted by a narrow passage. ‘I'wo preparations were put up in this way and two closed. After 24 hours in the incubator at 23° C. spores were seen to be swollen in all the specimens, and in the closed cells they had begun to develop buds. After 72 hours these buds had elongated into distinct mycelial filaments, which were longest towards the end of each hair where the jelly had accumulated. The open specimens contained micrococci and bacteria, and had shown no further sign of growth. On the sixth day the mycelium had extended into long filaments, showing septa in places. Experiment 4.—Six more specimens were mounted, all in closed cells as before. Swelling and budding took place within 48 hours. On the third day mycelial growth was distinct in four. One specimen had dried up ; in the other, bacteria had developed and obscuted the spores. The mycelium became septate during the next four days, but as the fluid gradually evaporated, growth ceased, and by the ninth day all were dried up. Experiment 5.—Six more specimens were prepared in the same manner. Growth took place in all within 72 hours. On the fourth day oil from the putty had mixed with the fluid of the jelly in three, while the remaining three had dried up. Experiment 6.—At this point putty cells were given up and hollow glass cells, circular and oval, were used instead. Hairs from the same case were placed at the bottom of the cell and completely covered with the gelatine peptone. Cell was closed with a cover-glass. Three specimens were placed in the incubator at the temperature of 23°C. In 24 hours the spores had swollen and begun to bud. In 48 hours distinct filaments were growing ~ from sides of the hairs, chiefly towards the ends. Specimens were then left at room temperature, and on the fourth day filaments had grown twice the length, and showed septa. Isolated spores, which had been separated from the hair, had also produced filaments. On the sixth day contents of filaments were becoming granular, and highly refractile spaces began to appear near the ends, in the midst of the protoplasm. In places two filaments or more were seen arising from one spore. ‘The protoplasm next became aggregated in the centre of the filaments, and further growth ceased. Frag- Ringworm Fungus. By M. Morris & G.C. Henderson. 331 ments of jelly containing these bodies were transferred to fresh slides and gelatine peptone, but no growth took place from them. Hzperiment 7.—Ten specimens were prepared in a similar manner to the last mentioned, with uniform results in every case. Growth ceased before formation of definite fructifying organs. Experiment 8.—Seven new specimens from a fresh case of typical ringworm were prepared as before and placed in the incubator at 24° C. After 24 hours spores were pear-shaped. In these specimens several isolated spores were watched from day to day. In 48 hours the buds had elongated into filaments, no bacteria or adventitious fungus having appeared in the meantime. In three of the specimens growth ceased on the sixth day, but in the remaining four, which had a less amount of peptone, growth extended to the margin of the jelly, branching freely, and finally sending off twigs at an angle of 45°. Some filaments presented pear-shaped enlargements at their ends. During the next three days these enlargements underwent no further change, but the other terminal filaments commenced to form basidia, sterigmata, and chains of spores in a manner similar to Penzeci/limm. Some of the spores, when removed to fresh gelatine peptone, grew into exactly the same forms of filaments and fructification. They also produced when placed on the human skin beneath a watch-glass fixed by plaster, a crop of itching papules on the third day, and these about the sixth day coalesced to form an erythe- matous patch, the centre of which gradually faded and desquamated, while the margin spread centrifugally, like a typical patch of ring- worm. After washing the surface, scales of epidermis were removed — from the margin, and on soaking in liquor potassee, were found to contain numerous spores, identical in appearance with Trichophyton tonsurans. The second generation of spores also produced a typical patch of ringworm, which contained fungus. Haperiment 9. Cultivation in tubes—Twelve tubes, six with hairs at the bottom of the tube, six with hairs floating on the surface of the gelatine peptone. The tubes had been sterilized with care by heating in the flame of a spirit-lamp to dull redness and then plugged with wool. In 24 hours spores in both sets were swollen, pear-shaped, and some had short filaments. During the next day mycelial growth continued. On the sixth day the hairs on the surface had begun to throw up whitish aerial hyphe, which in two days developed abundant spores. The spores on the submerged hairs produced very long fila- _ ments, the protoplasm of which began to become granular and aggregated in places about the seventh day, then ceasing to grow. _ Healthy hairs submerged and floating in the same way showed no results. Experiment 10.—Spores were removed from the fructifying 332 Transactions of the Society. hyphe of the previous experiment, and planted in fresh tubes in a similar manner. They grew into mycelium, which fructified exactly as in Experiment 9. These experiments have been repeated several times with uniform results. Lire- History. A. Spores as met with in ringworm hairs are small, round or ovoid bodies, which vary in size from 3 yw to 7 pw, and are highly refractile in appearance. ‘They are arranged in lines in the substance of the hairs, while on the surface they form a thick coating obscuring the mycelium from which they spring. (Plate VIL. fig. 1a.) B. 12 hours’ cultivation—After 12 hours the spores become swollen to three or four times their original size. Their contents are more hyaline and less refractile, and at one or ‘more points of the circumference a minute protrusion appears, making the spore pear-shaped. (Fig. 10.) C. 24 hours’ cultivation—In 24 hours the protrusion becomes elongated into a retort-shaped body. In many cases a distinct constriction marks the spot at which the filament arises from the spore. (Fig. 2.) D. 48 hours’ growth.—In 48 hours some of the filaments had reached a length of 0°7 to 0°9 mm., becoming more or less tortuous. (Fig. 3.) E. Third day—During the third day growth of filaments and twisting continues. F. Fourth and fifth days—During the fourth and fifth days the filaments increase in length and branching takes place. No other change. G. Siath, seventh, and eighth days.—By continued branching of filaments a dense network is formed, and in preparations in which entire hairs were placed it was impossible to trace an individual filament from spore to termination. (Fig. 4.) This, however, we have done in specimens in which isolated spores have been sown. At this stage, in portions of the mycelium, the protoplasm shows in its centre brightly refractile spots varying in size, and septa are seen immediately above the point of branching. (Fig. 5.) H.—The end of some of the filaments show bulbous and pear- shaped enlargements, but these do not in any case go on to spore formation. I. Aerial hyphex and fructification.—As soon as the filaments reached the margin of the jelly and were exposed to air they divided into two or three short branches, on the extremities of which a basidium and sterigmata were developed. (Fig. 6.) Ringworm Fungus. By M. Morris & G. C. Henderson. 333 These spores in size and appearance resemble those of ring- worm. In some instances the filament ends in a single chain of spores instead of the usual brush. K. Second generation—Spores taken from the fructifying growth of the first generation, when placed in fresh cells, swelled and grew in exactly the same way as those derived from ringworm patches. Spores, when removed from the fructification of the second generation, produced, when planted on the human skin, a typical patch of ringworm. Remarks.—One of the main difficulties which previous ob- servers have had to contend with in their attempts to determine the botanical position of the ringworm fungus, has been the frequent development of adventitious fungi on and in the medium used for the cultivations. In order, therefore, to obviate this difficulty it appeared to us necessary that the medium used for cultivation should possess the two following properties :—1. Perfect sterilization. 2. Sufficient consistence to retain spores in a fixed position for continuous observation. 1. The gelatine peptone was sterilized by boiling it ten minutes daily for a week. The cells and cover-glasses were heated in the flame of a spirit-lamp to dull redness. The forceps, needles, &c., were heated also. ‘he only opportunity for accidental entry of germs was during the brief interval of transferring to the cells the gelatine and ringworm spores from the closed tubes in which they were kept. In our earlier experiments with aqueous and vitreous humours we found, like other observers, that the growth of the fungus was interfered with by the presence and rapid development of micrococci and bacteria. We therefore discarded these media for the gelatine peptone, which could be more easily and thoroughly sterilized. 2. In our next experiments with spores placed on the surface of gelatine peptone, we were unable to exclude the possibility of the simultaneous deposition of spores from the airin which the jelly was exposed, nor could we follow the growth of individual spores after about 48 hours. However, by growing the spores entirely imbedded in the substance of the jelly, we were able to watch from day to day the gradual alteration in the shape of the spores, and the subse- quent growth of mycelium from them. In fluids, on the other hand, the diffusion which takes place causes a complete intermixture of the accidentally introduced fungi with the growth derived from the _ spores implanted, while in the jelly the growth from each centre retains a fixed position. If, then, the original spore was a ring- worm spore, the growth which we have traced from it to fructifica- tion must belong to the same plant as that causing the disease. 334 Transactions of the Society. With the exception of the rmgworm spores, and any accidentally admitted with them into the cell, adventitious fungi can only enter from the margin, where they can be easily detected and removed. In control experiments with healthy hairs no fungoid growth at all took place, and many specimens remained absolutely barren, while in others a few stellate masses of Penicilliwm and Aspergillus made their appearance at the margin. When a portion of a ringworm hair crowded with characteristic spores was placed in the incubator, the mycelial growth sprouted luxuriantly from all parts of its surface and soon formed the dense network described. Isolated spores when scraped from a typical ringworm hair (first proved microscopically) germinated and grew in the same way as those attached to the hair. The figures of this commencing growth will be seen to agree with those of Grawitz, Atkinson, and Thin. It is only in the further development of the fungus that our results are different to these authors. In nearly all our culti- vations the temperature of the incubator was maintained at about 23° to 24° C., the growth of the rmgworm spores being sufficiently free and the stages of development somewhat prolonged so as to allow more easy observation. Though the fungus germinated at from 35° to 38° C., the greater number of the preparations were spoiled by the development of bacteria. The premature drying up of the jelly led us after several trials to fix the limit of heat at 24° C. When the temperature fell below 10° C., the growth of filaments ceased and no fresh spores germinated. Some of the experiments of previous observers for the object of comparison :— 1. Neumann, about 1871. 2. Grawitz, in 1877. 3. Atkinson, in 1878. 4, Thin, in 1881. Neumann* used the following method. On a glass slide were cemented two parallel slips of glass, on which was laid a cover-glass with a drop of nutrient material on its under surface. The cover- glass, as well as the slide, was moistened with pure water. The objects to be cultivated were placed close by or on the surface of the nutrient material. ‘To purify the cover-glass and slide, they were washed carefully, rubbed dry with writing paper, and finally bathed in ether and alcohol. As media, Neumann used egg-albumen alone, or in combination with sugar of milk, with or without tartrate of ammonia; tartrate of ammonia and sugar of milk; also paste, starch, phosphate of * Arch, f, Dermatol. u. Syph., 1871. ‘Lehrbuch der Hautkrankheiten,’ 1871. Ringworm Fungus. By M. Morris & G. C. Henderson. 335 ammonia, phosphate of potash and soda, phosphate of lime, sulphate of quinine, sulphate of magnesia, and glycerine alone or variously combined and frequently with the addition of organic acids, especially citric. ‘These substances had been sterilized, with the exception of albumen, by being kept in a powdered state for a long time in absolute alcohol. Albumen was used only after its freedom from fungi had been ascertained by some days’ observation. “The results of my experiments confirm the clinical observation of Hebra as to the origin of Herpes tonsurans and Favus from one organism, viz. Penicilliwm. In some cases I also demonstrated Trichothectum as the cause, but never succeeded in obtaining Aspergillus.” Neumann’s results were obtained after cultivations extending over weeks and months. Grawitz * took great precaution to sterilize his slides and all the apparatus used after the manner of Brefeld, that is by boiling or heating to redness. One or two drops of the medium were placed on a slide mixed with the spores to be grown, and covered with a watch-glass to keep off dust and foreign spores. These preparations were placed on a stand under a bell-glass. The medium used was gelatine dissolved in sufficient boiling distilled water to form when cool a trembling jelly, and slightly acidulated with lactic or citric acid, to check development of bac- teria. He also used an acid solution of meat extract. He noticed germination of spores and formation of branched filaments from them, but as will be seen from his figures, the sub- sequent mode of growth differed in the three experiments in which the fungus came from different sources. Atkinson} used cell-cultivation. A glass ring fastened with Canada balsam on a slide formed the cell, at the bottom of which a drop of distilled water was placed to secure moisture. A small quantity of the nutrient material with the fungus sown in it was placed on a cover-glass, this was inverted to form the roof of the cell and kept in position with oil. The oil, water, and nutrient fluid were sterilized by boiling, and the cell and cover-glass were made scrupulously clean. Pasteur’s fluid, with or without sugar, decoction of horse-dung, aqueous humour, gelatine, currant jelly, and meat infusion, were used, but orange juice seemed to be the most suitable. In the majority of cases the cell remained quiescent. When successful, growth begins in 24 to 36 hours, or several days. The spores swell, but form filaments, which spring medusa-like from the hair, branch, form septa (third day), and become bulbous at the ends and throw off short sporangium-bearing hyphe. On the fifth day * Virchow’s Archiv, lxx. (1877). + New York Medical Journal, 1878. 336 Transactions of the Society. hyphz and mycelium become vacuolated, sporangia show “aggre- gations of protoplasm, the future spores, and occasionally bud.” Sporangia were most frequent in under-fed cultivations. Atkinson believes Trichophyton to be a Mucor, presenting some differences from Mucor mucedo. Thin* used cells, the hair being placed on under surface of the cover-glass and a drop of fluid placed over it, sometimes so as to cover it, at others only to moisten it. ‘To prevent evaporation a ring of damp blotting-paper was put at the bottom of the cell, which was then kept in an incubator at 92° F. to 98° F. (83°3° C. to 36°6° C.), most usually 96° F. to 98° F. (85°4° to 36°6° C.). He also carried out mass cultivations in protected flasks, on the surface and in the deep. No mention made of sterilization. Aqueous and vitreous humour, the latter chiefly in successful experiments. Several other fluids were used but with no success. In cells, spores elongated after a few hours and formed mycelium during two following days, which ceased to grow after having attained a very moderate length, spore formation soon taking place. In flasks, similar results. Bacteria appeared in all cases, adventitious fungi frequently avoided (in 9 out of 12). Haperiments.—Three cells, twelve flasks, in eight of which Trichophyton developed. In one case, after being at room tempera- ture in flask from April 20 to May 3rd, it had grown only as much as two days in the incubator. “Growth observed consisted in a development of mycelinm from spores, and in the formation of spores within the mycelium, as is portrayed in the drawings. No organs of fructification were observed.” Hairs which had been immersed in water for six days, or which had been submerged in vitreous humour showed no sign of growth. Thin’s conclusions are, i. That Trichophyton is not one of the common fungi. ii, That it can be cultivated artificially when moistened with vitreous humour. ii. When covered with vitreous humour it does not grow. REMARKS. In comparing the above-described experiments, we notice that Neumann’s method, though giving results which coincide with our own, is open to the objection that adventitious fungi could find their way by means of the air to the medium in which the cultivation was then taking place, as his cells were not closed and had to be frequently removed from the incubator for purposes of observation. ‘The long interval which elapsed before growth took place also rendered it more probable that the various fungi observed by him were adventitious. To Grawitz we are indebted for the idea of using gelatine as one of the constituents of our medium. ‘The difference between * Proc. Roy. Soc., 1881. Ringworm Fungus. By M. Morris & G.C. Henderson. 3837 his results and ours may possibly be due to the acidity of his medium. We can offer no other explanation of the great differences between the three specimens which he figures. Atkinson’s results, as shown in his first figure, exactly corre- spond with our own. It is only in the latter stages we differ. The large sporangium-like bodies and lateral buds, which led him to assign ringworm to the Mucors, seem to correspond with the terminal masses described in section H. In Thin’s cultivations, the swelling and budding of spores and the early formation of mycelium agree with the facts previously described by Grawitz and Atkinson, and now confirmed by our- selves. We are inclined, however, to think the appearances which he considers to be spores, are spaces in the protoplasm of the mycelium, filled with highly refractile fluid, as in the longest filaments, which were observed by us for some weeks, these bright roundish spaces gradually enlarged and coalesced, while the proto- plasm shrivelled up and disappeared. Kobner * believes that these so-called spores within the filaments and terminal buds are only oil-globules. In using vitreous humour we found, like Thin, a very abundant develop- ment of bacteria, and in proportion to their growth a coincident cessation of that of the ringworm. CoNCLUSIONS. We think that the experiments we have described warrant the following conclusions :— 1. That the spores of Trichophyton tonswrans grow freely on the surface, and in the substance of gelatine peptone at tempera- tures between 15° and 25° C. 2. That the mycelium only will grow on the substance of the jelly, and that the hyphe require air to produce conidia. 3. That the branching, septa formation, and fructification are identical with those of Penicilliwm. 4, That spores of the second generation reproduce ringworm on the human skin. 5. That outgrowths resembling “ resting-spores” appear on some of the filaments. * Virchow’s Archiv, xxii. (1861). + We have to express our great obligation to Dr. Maddox for the photo- micrographs which he has produced to illustrate this paper. The power used was a Beck 1-5th, and the amplification was 1000. Ser. 2.—Vot. III. Z, 338 Transactions of the Society. IX.—On a Portable Form of Aéroscope and Aspirator. By R. L. Mappox, M.D., Hon. F.R.MS. (Read 11th April, 1883.) Serious attention to the ordinary and morbific conditions of the atmosphere having, at last, gained a place in the study of such causes as may be supposed to originate or accompany zymotic and contagious diseases in their course, I venture to offer to those inter- ested in such studies a portable form of aéroscope and aspirator combined. It was found capable, with a single aéroscope, of de- livering 12 to 16 pints of air by the use of one pint of water. For exhibiting it in action, I have adapted two aéroscopes, the air being drawn through each by one trompe or aspirator. To Dr. Miquel, of the Microscopical Department at the Observatory of Montsouris, in Paris, we are largely indebted for some most interesting articles in the late yearly publications of the ‘ Annuaire de | Observatoire de Montsouris, on the microbes of the atmosphere, and who, by the continued, laborious, and patient study of the air, dust, water, &c., in different localities, reduced to comparative and statistical data, has been enabled to publish separately, a very enlarged, well-illus- trated and comprehensive work on this most difficult subject.* Iam indebted to Dr. Miquel for considerable information about the simplest and best form of trompe, and I have here adopted in a simple way the form he has so successfully used. Dr. Miquel writes to me that by carefully proportioning the size and length of tubes, and the inflow of the water, a large delivery of air can be secured. In his letter he figures a form he employed in the country: a tank holding ten litres of water being suspended from’a stout branch of a tree, to which also the aspirator is fixed, whilst the aéroscope is placed on a tripod set up at a little distance, the water and air passing from them to another tank on the ground; 10 litres of water sufficing to obtain the passage through the aéroscope of 10 cubic metres of air, delivering from 10 to 11 litres per hour. In the form ex- hibited, the whole is in rather a limited area. The object being to lessen weight and the chance of breakage, bladders are employed as vessels for the water and air collected. The description of the double form is given, as from it the arrangement of the single one can be readily deduced. I venture to suggest that the plan could be easily utilized in the wards of hospi- tals, or in the fermenting or other chambers of large breweries when requiring only a temporary or qualitative examination of the air. *<*Les Organismes vivants de l’Atmosphtre, par P. Miquel, Docteur és. Sciences, Docteur en Médecine, Chef du Service Micrographique & 1l’Observatoire de Montsouris, Paris, 1883, 308 pp, avec figs. See also infra, p. 403. On a Portable Form of Aéroscope, &c. By Dr. Maddox. 339 When long examinations are needed, it would be better to use a larger form of apparatus, or at any rate a larger supply of water and some form of meter to register the exact amount of air trans- mitted in a definite time. The aéroscope A (fig. 58) is made of a short wide glass tube, brass mounted at each end, and rendered air-tight by indiarubber washers. The parts are separable. The brass tube that holds the short ground neck of the glass funnel inside the cap, supports a bent Fie. 58. wire platinum cradle, which car- ries a thin glass cover, smeared —> in the centre of the surface to- wards the funnel, for about half an inch, with glycerine simply, or mixed with gum or glucose. The brass cap at the opposite end to the funnel is pierced by a short metal tube 3-8ths of an inch bore. The aéroscope B is a turned boxwood box, the top unscrew- ing below the shoulder—one of the boxes sold by chemists made to contain a stoppered short 1- ounce or 10-drachm bottle, the bottle beg removed; the bottom is turned out to fit a small pointed conical glass funnel, which is cemented into the box; a small metal cradle, the spring sides of which press against the inside of the box, carries the thin cover - glass smeared with some sticky ma- terial, and can be pushed nearer to the point of the funnel or withdrawn as required, being usually placed about the 1-30th | K of an inch. The distance much depends upon the force of suc- tion of the aspirator. The aper- tures of the funnel vary from about the 1-50th to the 1-80th of an inch. The top of the box has screwed into it a short metal tube. The aspirator or trompe is a small conical, round-shouldered glass vessel, of about one ounce capacity, open at both ends. On the larger end fits tightly Zz 2 ——— 340 Transactions of the Society. a laboratory caoutchouc cap with two tubes; into the smaller or neck end fits air-tight a short (14 inch) ground metal tube. The two aéroscopes are fixed to a small base-board by two stout indiarubber bands, which pass through two saw-cuts at each end of the board. ‘This board is fastened on the top of a 53-feet tripod stand. A bladder or a small can containing a certain quantity of water is hooked to the under surface of the board, a flexible siphon tube dips into the water, reaching to the bottom of the vessel, the long leg of the siphon being fitted with a small stopcock with a long conical nozzle. On the lower end of the short metal tube of the aspirator is fitted an indiarubber tube about 9 inches long and 2-8ths of an inch bore; a complete loop is turned on the tube almost close to the metal tube, being held in place by a letter S zinc clasp; the other end of the tube slips over a piece of glass tube of the same bore, about 9 inches long, this forming the index- tube. To the lower end of this glass tube is adapted another caoutchouc tube, which at the opposite end fits on a small stopcock fastened into and passing through the neck of a second bladder, which in use rests on the floor against one of the legs of the tripod. In the neck of the same bladder is a short metal tube, to which is fixed another indiarubber tube that leads to and is fixed on a small stopcock secured in the neck of a third and much larger bladder, suspended by its neck, with stout twine, between the legs of the tripod. The stopcock tube and the second tube are best soldered into a brass tube before it is fixed in the neck of the second bladder ; corks do not answer well. The exit ends of the aéroscopes are each joined by caoutchouc tubes to the spread branches of a Y-shaped metal tube, the lower end of which fits into one of the two tubes of the indiarubber cap of the little aspirator, which is held at a convenient height against one of the legs of the tripod by a couple of elastic bands. All the junctions must be made air- tight, and the top of the wooden aéroscope screwed down upon an indiarubber or greased leather washer. In use, the bladder or small vessel, No. 1, with its siphon, is filled with water, wholly or partially, and suspended from the under surface of the small base-board. The siphon being made to act by suction, and its stopcock turned off, the conical end of the nozzle is at once fitted into the unoccupied tube of the cap of the aspirator. The two other bladders (No. 2 and No. 3) are squeezed empty of air, and their stopcocks turned off and fitted to their respective tubes, The stopcock of the siphon is now opened, so that a drop of water may either drop at the rate, say of 70 to 100 per miaute, or else trickle along the side of the little aspirator; this, I think, gives more uniform results than when dropping. The stopcocks of the other two bladders are at once opened. The slow dripping of the water into the looped tube sucks over a considerable amount of air which On a Portable Form of Aéroscope, dc. By Dr. Maddox. 341 has passed through the aéroscopes; the air and water descend together pretty uniformly through the index tube, where the rate of flow is estimated, and pass into the bladder on the floor, the collected air soon passing off by its proper tube into the sus- pended bladder. This eventually gets filled, or if not quite filled, by the air-pressure, the stopcock of the bladder on the floor is turned off, and slight pressure made by hand. The stopcock is then turned on again and the stopcock of the air-bladder closed, released from its tube, and the air discharged; the bladder is then refixed as before, and the suction of the trompe continued until the water is expended, or as long as required. No. 1 and No. 2 bladders can be easily made interchangeable by temporarily suspending the action of the siphon. The capacity of the large air-bladder being known, and it being filled once or oftener, furnishes a rough esti- mate of the air drawn over. The time occupied can be also noted. The bladders are rendered flexible by being well impregnated with glycerine. N.B.—Since exhibiting the double form of aéroscope and aspirator I have constructed an instrument in which the aéroscope and aspirator are combined in one. For compactness it has advan- tages. It was exhibited in action at the Scientific Meeting of the Society on the evening of May 2nd. The instrument consists of two large brass tubes A, B (fig. 59), which screw together air-tight. A has cemented into it a small glass funnel C, drawn to a point. B is rather longer than A, and has a small brass tube D, open at both ends, soldered obliquely into it. Fic. 59. Near the inner end of this tube a portion is cut away, into which freely passes the fine end of another smaller tube EK, which is fitted air- tight into the closed end of B, and projects into the tube, go as almost to touch the opposite side. ‘The cover- glass with sticky material is held in a small cradle near to the fine orifice of the funnel. Air enters by C, and water by HE, which by gently dropping or escaping by the fine orifice into D, sucks the air through the funnel, and they both together pass off through the outer end of D, to which is attached the looped indiarubber tube, as in the double form. It can be used with the funnel looking downwards or horizontally. ‘To increase the fall and the air spaces between the drops of water passing through the index tube, an upright, about 15 in. high, was screwed to one side of the base board. To the top of the upright was hung an oblong tin vessel (box), into the lower end of which was fixed a small stopcock connected with the projecting end of the tube E, by a short caoutchouc tube. 342 Transactions of the Society. This plan was adopted instead of the bladder with siphon suspended beneath the base board, to hold the water supply. The box can be easily made of a length and size to hold the aéroscope, bladders, and tubes, for easy carriage. I tried suspending a bladder contained in a calico sac, for the sake of lessening the weight in the place of the metal box, but gave the preference to the box for the reasons given. With this simple form of aéroscope I have drawn over 460 measured ounces of air by seven ounces of water. Details have been dwelt upon, so that any one, after obtaining a proper funnel of glass, metal, or metal enamel-covered, can easily construct the rest. Care must be taken to see that the sticky material used does not contain any microphytes, or the results will be falsified. The tripod is not even a necessity, as by a little ingenuity the parts of the apparatus can be otherwise held in position. Careful regulation of the water- flow is necessary to obtain the greatest quantity of air sucked through the aéroscope by the least quantity of water. To increase the length of the fall tube, it was wound round one of the legs of the tripod, but without advantage, as friction appeared to delay the flow. The thin covers with the dust collected are placed down on a clean slide for microscopical examination. G284870) SUMMARY OF OURRENT RESEARCHES RELATING TO ZOO OGY AND BOLL AN ¥ (principally Invertebrata and Cryptogamia), MICROSCOPY, &c., INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS* ZOOLOGY. A. GENERAL, including Embryology and Histology of the Vertebrata. Mesoblast of Vertebrata.j — O. Hertwig discusses several im- portant points. 1. We have had statements to the effect that the mesoblast has a paired, and others that it has an unpaired rudiment. These con- flicting views are due to the fact that some authors regard the median set of cells as belonging to the mesoblast, while others look upon it as part of the endoblast; against this latter it may be urged that the set of cells in question cannot be separated off from the mesoblast, and against the former it may be said that there is no special peri-enteric cell-layer lying below it. In connection with this we observe that some authors regard the notochord as having a mesoblastic origin, but O. Hertwig believes that before long it will be generally allowed that, so long as the notochord is not definitely differentiated, the embryo, in the middle line, is still diploblastic. The dorsal median set of cells should not be called either mesoblast or endoblast, but the names of chorda-endoblast and enteric endoblast should be ascribed to the two parts in this region. 2. Taking next the vexed question of the origin of the mesoblast from the endoblast or ectoblast, we find that an explanation is afforded by the “ccelom-theory,” for both endoblast and mesoblast arise by the infolding of a membrane, which primitively bounded the surface of the blastula. In Amphioxus the gastrula-formation comes to an end before the endoblast has become more complicated, and then it seems as if the mesoblast arose from the endoblast. But in the higher * The Society are not to be considered responsible for the views of the authors of the papers referred to, nor for the manner in which those views may be expressed, the main object of this part of the Journal being to present a summary of the papers as actually published, so as to provide the Fellows with a guide to the additions made from time to time to the Library. Objections and ' corrections should therefore, for the most part, be addressed to the authors. (The Society are not intended to be denoted by the editorial ‘‘ we.”) + Jen. Zeitschr. f. Naturwiss., ix. (1882) pp. 247-328 (5 pls.). 344 SUMMARY OF CURRENT RESEARCHES RELATING TO Vertebrata the lateral mesoblastic masses begin to be developed before the gastrula-invagination is completed, and here it seems as if the mesoblast arose from the ectoblast. However, in both cases the final result is the same, and we cannot justly speak of any real difference in the genesis of the middle layer. 3. The explanation of the difference of opinion as to the origin of the notochord is partly to be found in the fact that the observers of some stages have examined embryos at a time when the median band passes directly on either side into the mesoblast ; and they, therefore, have ascribed a mesoblastic origin to the chord. Others have studied development more particularly at the period wken the chorda-endo- blast has become separated from the mesoblast and lies above the enteric glandular layer in the form of a thickened band of cells ; and they have asserted the hypoblastic origin of the chord. The following considerations appear to have an important bearing on the questions at issue. (1) Before the notochord becomes de- veloped the embryo is in part bilaminate, consisting of an ectoblast (medullary plate), and of chorda-endoblast which takes part in the delimitation of the enteric cavity. (2) On either side of this portion (median band) the embryo is trilaminate, if we regard the mesoblast as a simple layer, and quadrilaminate if we regard the mesoblast as consisting of parietal and visceral cell-layers, which only become distinctly separated on the appearance of the celom. (3) In no Vertebrate does the mesoblast arise by cleavage. (4) The mesoblast is only connected with the bounding cell-layers at the blastopore or at the primitive groove, where all three germinal layers are connected together, and at the two sides of the chorda-endoblast. (5) The mesublast arises peripherally and extends forwards, backwards, and ventrally ; in front of the blastopore it forms a paired rudiment separated by the chorda-endoblast, while behind the blastopore it is unpaired. (6) As the chief portion of the material for the growth of the mesoblast is derived from the cells, which, at the blastopore, or at the primitive groove, pass from without inwards, we are entitled to say that the process of invagination which commences with the forma- tion of the gastrula is carried on into later stages of development. (7) The process by which the paired mesoblastic bands separate from the neighbouring cell-layers and undergrow the notochord to inclose the enteron, may be so far modified that a lamella of cells from the chorda-endoblast may take part in it (Anura). The author supports the important doctrine that the ingrowth of the mesoblast may be looked upon as an invaginative process of epithelial lamelle by the following facts: (2) The mesoblast arises as a con- nected mass from masses of epithelial lamella. (f) In all Vertebrates a cleft appears early in the mesoblast which is bounded by epithelial cells, of a cylindrical or cubical form. The parietal and visceral mesoblast are, as is well seen in Elasmobranchs, at a very early stage epithelial lamella. (y) From these there arise true epithelial mem- branes and glands. (4) This view is supported by what is seen in Amphiowzus. («) The objection that the mesoblast of the Vertebrata arises as a single cell-mass and cannot therefore be regarded as equi- ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 345 valent to two epithelial layers, will have no weight for those who remember that in the Chetognatha the mesoblast appears, is lost, and again appears; that in Bony Fishes the nerve-cord is at first solid; or the mode of development of various sensory and glandular organs. Hertwig concludes by entering into a detailed criticism of the remarks of His on the “ccelom-theory ” of his brother and himself. The earlier part of the paper is occupied with the Amphibia— where Rana temporaria is taken as the type; in dealing with meso- blastic ova (Hlasmobranchs, reptiles, birds, and mammals) the author confines himself to discussing the observations of his fellow- workers, and drawing from them lessons which bear on his general conclusions. Inversion of Blastodermic Layers in Rat and Mouse.*—A. Fraser finds that in the common grey rat and the house-mouse we find the same arrangement of blastodermic layers as in the guinea-pig. The decidua appears to differ in the mode of its formation from that which ordinarily obtains, and the very early, rapid, and voluminous forma- tion of its solid mass appears to have some close and constant relation to the peculiar inversion of the blastodermic layers which is found in these rodents. Spermatozoon of the Newt.t—Mr. G. F. Dowdeswell describes a minute barb at the extreme point of the “head” of the spermatozoon of the newt, which has hitherto escaped notice. It is 2 » long and 1:5 w» broad. A similar structure was not found in other sperma- tozoa. It is suggested that the function of the barb is to attach the spermatozoon, and enable it to penetrate into the ovum in the early stages of fertilization, as has been shown to occur by Fol and others. Development of the Red Blood-corpuscles.{t—W. Feuerstack finds that nucleated red blood-corpuscles arise from colourless blood- cells ; the forms most closely allied to them are the ordinarily spherical coloured cells with an often disproportionately large nucleus—the so- called hematoblasts. Among these we meet with forms which present us with a series of intermediate stages between the ordinary red blood- corpuscle and the typical smaller hematoblasts with a proportionately large peripheral nucleus. The hematoblasts are derived directly from the colourless cells, in which the nucleus is much smaller. In Amphibia (e. g. Triton) and, to a less degree, in fishes, the formation of the red blood-corpuscle is not so regular as in birds, and we find therefore in them a much greater variety in the size of the hemato- blasts. The answer to the question where this blood-formation goes on is based on the supposition that we must look for it at such points as those in which we find the largest number and youngest stages of forms intermediate between coloured and colourless cells. In the pigeon these points are the osseous medulla, the spleen, the portal system, and the medulla of the young quills of the feathers. * Proc. Roy. Soe., xxxiv. (1883) pp. 430-7. + Quart. Journ. Micr. Sci., xxiii. (1883) pp. 336-9 (1 fig.). ¢ Zeitschr. f. Wiss. Zool., xxxviii. (1883) pp. 136-64. 346 SUMMARY OF CURRENT RESEARCHES RELATING TO In the frog they are the osseous medulla and the spleen, but in this animal the differences between the blood of these and other parts is not so well marked as in the pigeon. The osseous medulla appears to be the most important factor in the modification of the develop- ment of the colourless blood-elements, but it must be remembered that, without this medulla, there are developed colourless cells, which, taking up hemoglobin, become converted into red blood-corpuscles. In some of the cases where the medulla is wanting or reduced we find that the spleen is of considerable size (eels) ; at the same time, this organ may be extirpated and fresh cells be still produced. No unimportant part appears to be played by the lymph-sinuses, and attention must be given to such causes as are due to the slowing of the blood in some of the organs in which white corpuscles seem to be most largely developed. Origin and Destiny of Fat-cells.*—Some light is thrown upon the problem of the origin and destiny of fat-cells by the observations of Mr. 8. H. Gage upon those of Necturus. In the subcutaneous connective tissue of this creature the Microscope revealed the presence of fat-cells in all stages of growth: large branched cells with one or more fat-drops; cells containing one or two small fat-drops and a large one; and some large unbranched cells entirely gorged with fat. The pigment-cells were sometimes partly gorged with fat, and some small round or oval cells also con- tained fat. Thus it would appear that, as maintained by Virchow, Frey, Klein, and others, fixed or branched connective tissue corpuscles may become modified into fat-cells, and also, as asserted by Czajewicz, Rollett, and others, migratory corpuscles may become quiescent and turn into reservoirs of fat. After a Necturus has been kept upon sparse diet for some time, the adipose tissue shows but few gorged cells, many transitional forms, and a greater proportion of branched cells without fat, thus proving that the fat-cell is simply a store of food, and that, when their store is used, the cells revert to their primitive condition of branched or unbranched cells. Embryology of the Milk-glands.;—G. Rein summarizes the results ‘of his extended researches on the development of the milk- glands. The same type of formation was found in all the species investigated. Gegenbaur has maintained that the majority of mammals have their teats formed by an upgrowth of the area in which the lactic glands are developed; but that in ruminants there is another type, the glandular area forming a depression, the walls of which grow up around it intoa teat. Rein, however, demonstrates that the ruminants conform to the usual development. His investigations may be sum- marized as follows :— The first trace of the milk-gland appears very early, usually when the visceral clefts are closed ; in man, during the second month. The gland first appears as an ingrowth of the epidermis. The connective * Amer. Natural., xvii. (1883) p. 444. ¢ Arch. f. Mikr. Anat., xxi. (1882) p. 678. Cf. Science, i, (1883) p. 53. ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 347 tissue of the nipple is next formed; the teat may be developed early (ruminants, horse, &c.), or at the end of foetal life (man). Next secondary outgrowths arise from the primitive epidermal bud, as many as there are ducts in the adults. At this period the differentiation of the stroma from the mesoderm begins. Most of the primitive in- growth disappears, a little remaining as the common orificial duct. The secondary epithelial growths, on the other hand, grow farther, become tubular, branch, and finally form the ducts (sinus and ducts proper) and the acini. In the human foetus all the parts of glands are developed by the time of birth. The development is according to this same plan in all the animals investigated, comprising species of Primates, Insectivora, Carnivora, Ungulata, Glires, and Didelphyda. The so-called Montgomery glands are rudimentary milk-glands. The view advanced by Creighton and Talma, that the acini are developed from the mesoderm, is incorrect. The milk-glands cannot be regarded as modified sebaceous glands, but are organs sui generis. Caudal End of Vertebrate Embryos.*—In his studies on the development of Melopsittacus, Braun observed that a constriction is formed around the end of the tail which leads to the construction of a terminal knob, connected by a thin stalk with the base of the tail. Into this nodulus caudalis the chorda and medullary tube originally extend; but they afterwards withdraw from it, leaving the nodulus, a ball of mesoderm covered by epithelium, to be finally resorbed. This discovery led Braun to search for similar structures in mammals, and he now publishes his results. His investigations were made prin- cipally on sheep embryos, and observations were also made on those of other species. He finds an homologous structure, having, how- ever, more usually a thread-like form. In sheep it may be readily seen in most cases when the tail is from 1:5 to 3 mm.long. His general results are :— 1. The tail of mammalian embryos consists of two parts, an anterior or basal vertebrate ; and a posterior invertebrate and smaller portion, which, from its usual form, may be called the caudal thread. 2. The vertebrate portion may be partly or wholly imbedded in the body (internal tail), and terminates at the sacral vertebre in front ; the division of the tail which protrudes is the external tail. 3. The caudal thread contains originally the terminal portions of the chorda dorsalis, the medullary tube, and the caudal gut (Schwanzdarm), These are the first parts of the thread to be resorbed; the rest dis- appears later, the epidermal covering lasting longest. 4. The caudal gut is a rectal cecum; before it is resolved it breaks up into single parts, of which those in the tip of the tail endure the longest. 5. The chorda dorsalis projects beyond the last vertebra, its ending being often forked or contorted. 6. The medullary tube reaches to the tip of the tail or the base of the caudal thread, and its posterior end is probably resorbed. Braun further believes that he has found traces of a neurenteric _* Arch, Anat. u. Physiol., Anat. Abth., 1882, p. 207. Cf. Science, i. (1883) _ p. 261. 348 SUMMARY OF CURRENT RESEARCHES RELATING TO canal in sheep embryos. He adds a discussion of the tail in human embryos. Finally he homologizes with the embryonic caudal thread, the soft ceceygeal appendix of Inuus pithecus, and similar structures found abnormally in the chimpanzee, orang-outang, and man, and gives citations to prove that the caudal thread exists in human embryos. Influences which Determine Sex in the Embryo.*—Prof. E. Pfliiger publishes at length an account of experiments, performed with the greatest care, with the object of throwing light upon some of the most prominent of the obscure problems of the physiology of generation. He made use of frogs in his experiments; many hundreds of the creatures were obtained from various neighbourhoods, and were maintained while under observation under conditions made as nearly normal as possible. The first question dealt with is: Does the concentration of the spermatic fluid of the male influence the sex of the offspring? Much care is necessary in handling frogs’ eggs, for they are exceedingly susceptible of mechanical injury. The pair of frogs are parted during the sexual embrace, and therefore at a time when the products of the generative organs are presumably ripe, the animals are killed, and the spermatic sacs of the males are emptied into a watch-glass. A second watch-glass, filled with water, is impregnated with sper- matozoa by dipping into it the tips of the fine pair of scissors which has just been used to cut open the spermatic sacs and has, therefore, some of their contents clinging to it. The dilute spermatic fluid of the second watch-glass was often further diluted from ten to twenty volumes, and from these new mixtures fresh quantities of water in watch-glasses were impregnated by the transference of a film of fluid clinging to the scissors’ tips. Into these watch-glasses, filled with the fluid of a single male in different states of concentration, there were allowed to glide some of the eggs of the female taken from the right uterus. The experiments established two facts, first, the fertilizing power of the spermatic fluid was not diminished by dilution, all the ova were fertilized in each observation; second, dilution of the male fluid had no effect on the sex of the frogs which came to maturity after the artificial fertilization. In young frogs there are three varieties of sexual character, male, female, and hermaphrodite. The hermaphrodites become finally either male or female, but in their earlier stages they have the sexual organs of the female only; in those which are finally to become males, the testicles gradually develop round the ovaries and the latter are resorbed. This apparent numerical predominance of the female in early stages of the fuller formed frog has led some investigators astray. The author finds that no Batrachian egg segments without previous fertilization. The fertilizing power of the male fluid diminishes greatly and progressively after the season for sexual union. * Pfliiger’s Archiv, xxix. Cf, Amer. Natural., xvii. (1883) pp. 441-2. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 349 It is impossible to produce offspring by the union of the male and female products of two different Batrachian species, though seg- mentation of the egg, frequently of abnormal type, may be started by this artificial union. Sense of Direction in Animals.*—The remarkable faculty which cats, dogs, pigeons, and other animals possess, of returning in a straight line to a point of departure, has awakened much curiosity on the part of naturalists. Some refer it to instinct, some to intelligence similar to that of man, some to an internal mechanism which makes the animals simply automata; but none of these attempted explana- tions do anything towards solving the mystery. Wallace supposed that when an animal is carried to a great distance in a basket, its fright makes it very attentive to the different odours which it encounters upon the way, and that the return of these odours, in inverse order, furnishes the needful guide. Toussenel supposes that birds recognize the north as the cold quarter, the south as the warm, the east (in France) as the dry, and the west as the moist. Viguier, in the ‘ Revue Philosophique,’ publishes an original memoir upon the sense of orientation and its organs, in which he attributes the faculty to a perception of magnetic currents. Cerebral Homologies in Vertebrates and Invertebrates.{—In this very interesting contribution Prof. Owen distinguishes between the neurcesophageal and the hemcesophageal aspects of an animal’s body; and speaks of the side of the body of a cuttle-fish denoted by the neurcesophageal (“ subcesophageal” so-called) brain-part, with the chief nervous extensions therefrom along the trunk, as the “neural aspect,” and the opposite side to which the hemcesopha- geal (“supra-cesophageal”) brain-part has been turned by the course of the gullet, as the “hemal aspect.” What is usually called the upper surface in Invertebrates is the “hemal” one, and the lower the “neural” one. So the heart in man indicates the “hemal” aspect, the myelon the “neural” part of his body, as in the animals below him whether vertebrate or invertebrate. Attention is directed to the fact that in Invertebrates there is not the same concentration of sensory organs as in Vertebrates, an1 that among the latter themselves we find (e. g. Cyprinoids) the olfactory separated by long cords from the optic ganglia. Tho “ suboesophageal ganglion” is regarded as the homologue of the medulla oblongata, or “so much of that myelencephalous tract as may be in connection with the trigeminal and hypoglossal nerves,” or, in other words, with the part that affects the vertebrate mouth. The ear in Orthoptera is found in the first pair of legs. Basing himself on these and other facts, the author concludes that “the collective neural centres and their intercommunicating tracts in Invertebrates are the homologues of those centres and tracts called ‘brain and spinal cord’ in Verte- brates, and that such ‘neural axis’ marks, in both grades of the * Chron. Industr., Nov. 2, 1882. See Journ. Frankl. Institute, cxv. (1883) p- 314. + Journ. Linn. Soc. (Zool.), xvii. (1883) pp. 1-13. 350 SUMMARY OF CURRENT RESEARCHES RELATING TO animal series, the same position in the body, and the same local relations to the vascular centre and the alimentary canal.” The fore- most portion in Arthropods is simply displaced by the course of the gullet in order to open by a mouth on the neural aspect of the body. Where, as in Vertebrates, there is no cesophageal obstacle, the main cerebral centres become more closely approximated. In fact, the difference between the central nervous system of Vertebrates and Invertebrates is to be found in the “altered relation thereto of the gullet and mouth.” B. INVERTEBRATA. Apparently New Animal Type (Trichoplax adherens). *— Prof. F. E. Schulze records the discovery of an animal quite different from anything hitherto known. It was observed in the sea-water aquarium of the Zoological Institute at Graz. It is a thin plate about 0-02 mm. thick, and only a few millimetres in diameter. It constantly changes its form. It is translucent, and greyish-white in colour. At rest it is rounded in outline, but may draw itself out into a long thread, which may so curl and twist that it recalls a Persian or a Turkish letter. The movements are usually so slow as to be barely perceptible as the animal creeps along upon its under surface. Microscopical examination shows that the whole surface of the body is ciliated. Close under the upper surface is a layer of highly refractile balls from 5 to 8 p in diameter, and distributed pretty evenly. Besides these there are other balls nearer the under surface, which seem to be essentially different from those first mentioned. There is no indication of internal organs, nor of only bilateral or radiate symmetry: the organism is uniaxial. Schulze names it Tricho- plax (the ciliated plate), with the specific name adherens, because it clings so closely to the surface on which it is moving. Such an organism one would expect to find related to the Protozoa; far from it, for two different epithelial layers of cells form its upper and lower surfaces, and contain between them a fully developed layer of connective tissue. The upper epithelium is composed of large, flattened, polygonal cells; the lower epithelium, on the contrary, is composed of cylinder-cells, whose outer ends form a mosaic of small polygons, but whose inner ends terminate in processes that are lost in the connective tissue. This last, forming the middle layer of the body, consists of spindle-shaped and branching nucleated cells, which are probably contractile, and are imbedded in a hyaline basal sub- stance. The balls above mentioned are contained in large cells. There are, then, three layers, which from their relations would natu- rally be compared with the ectoderm, mesoderm, and endoderm of other metazoa: but the justification of this comparison must await a knowledge of the development of the organism. Professor Schulze speculates as to the relationship of the creature, but finds it impossible to assign it to any known class. Although it has been watched for a year, no sign of metamorphosis or of repro- * Zool. Anzeig., vi. (1883) pp. 92-7 (2 figs.). ZOOLOGY AND BOTANY, MIOROSOOPY, ETO. 351 duction has been observed; but he thinks it possible that it may have multiplied in the autumn by division. Mr. C. S. Minot thinks* that the animal bears a strong resem- blance to a sponge-larva. Chlorophyll of Animals.;—In the introduction to this very im- portant paper on the morphological and physiological significance of chlorophyll in animals, K. Brandt resumes the results of his earlier investigations, in which he set himself to demonstrate that chlo- rophyll formed by animals is never found; that, where present, it is due to the presence of unicellular alge; and that the animal hosts may be nourished owing to the assimilative power of these alge. Commencing with an account of the “ yellow-cells,” he gives a list of the animals in which they have been observed—Foraminifera, Radiolaria, Flagellata, Ciliata, Sponges, all three groups of Ceelen- terata, two Echinoderms, one Bryozoon, three Turbellaria, and one Annelid. The algal nature of the yellow-cells is next discussed, the views of Geddes criticized closely, and the algal nature upheld ; the organization of these bodies is discussed in detail, and the characters of the different forms found in various animals described and criticized. This section of the essay concludes with a discussion of the question, to what group of alge these yellow-cells belong, and the result is arrived at that they are the resting-stages of various marine algze, and especially of the Melanophycee. The further detailed result may be left to professed physiologists. After some account of the pseudo-chlorophyll bodies, the author passes to the symbiosis of animals and alge; animals may live inde- pendently of alge, and alge of animals, but the Radiolaria appear to be very dependent on their guests. After having convinced himself of the fact that yellow-cells can nourish their animal hosts, Dr. Brandt turned to the mode in which this is effected; in the Collozoa he found, after treatment with iodine, numerous small granules of starch in the protoplasm of the animal. As these were specially numerous on the outer surface of the yellow-cells and in the neigh- bourhood of completely intact yellow-cells, and agreed in all their important characters with those found in the cells, they may fairly be regarded as assimilative products of the yellow-cells that have become free. From these observations it is clear that the assimilation pro- ducts of the living yellow-cells may partly serve the animals, and it is possible that in animals the assimilative processes of the alga go on more actively, inasmuch as they are there more richly provided with carbonic acid than they are when free in the water. In fine, the author has no doubt that the guests do provide starch for their hosts. Some experiments have been made on the production of oxygen which have led to the following conclusions :—Alga-containing Actinie, if brought from diffused into direct sunlight, exhibit no irritation, if means are taken to prevent a rise in temperature. If the * Science, i. (1883) p. 305. + MT. Zool. Stat. Neapel, iv. (1883) pp. 191-302 (2 pls.). 352 SUMMARY OF CURRENT RESEARCHES RELATING TO Actinie are gradually heated from 26--27° to 35-36° C., the movements of alga-bearing or alga-free Actinize become more lively, and this is true whether the change is due to sunlight or to artificial heating, with careful exclusion of the light. If alga-bearing Anthozoa’ are subjected to direct light they are killed, and this not because of the great production of oxygen or the influence of the light, but in con- sequence of the heating; the production of oxygen does not seem in any way to affect the result. All alga bearing Actinize throw off a number of yellow-cells when subjected to heat; treatment at 30° for some time or at 35° for a shorter resulting in the presence in the surrounding water of irregular brown masses, which contain a large number of yellow-cells, which were still completely capable of development or of assimilation; and this even obtained when the Actinize were themselves killed. Yellowish-green and yellow Zooxanthelle are only found in animals living on the surface of the sea (Radiolaria, Globigerine, Siphonophora, Rhizostomide) ; brown cells in those which live ata slight depth, and red alge in sponges, which live somewhat deeper (15-35 m.). Division of Lower Invertebrates.*—C. Biilow gives in a collected form some of the scattered information and theories which affect the question of the apparently voluntary division, with subsequent re- generation, of Cclenterates, Echinoderms, and Worms, and gives some unpublished observations as to regeneration in the Gephyrea. Examining some living’ specimens of Phascolosoma vulgare and Aspidosiphon muelleri, he removed from five of the former and three of the latter a portion of their proboscis; the cesophageal ring was separated from the rest of the body, as well as the tentacles, the mouth, part of the retractor muscles, &c. In from three to five weeks all the lost parts were replaced, and the only apparent difference was to be found in a brighter colour and a greater transparency. Mollusca. Chromatophores of Cephalopoda.t—R. Blanchard finds that the chromatophore of the Cephalopod does not differ in the general characters of its structure from that of Fishes, Batrachia, or Lizards (Chameleo) ; it is a simple connective-cell charged with pigment, and possessing to a high degree the power of protruding amceboid pro- cesses from the centre of its amorphous central mass. All the activity is seated in the chromatophore itself, and the surrounding tissues take no part in accomplishing its movements; in fact, it may be well com- pared to an amoeba, charged with pigment, and independent of the dermis which incloses it. This amceba, however, is under the influence of the nervous system, as the observations and experiments of Briicke, Bert, and others have already demonstrated ; but it is not possible to agree with Harting in thinking that the radiating fibres seen in Cephalopods are * Biol. Centralbl., iii. (1883) pp. 14-20. + Comptes Rendus, xevi. (1883) pp. 655-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 353 nervous terminations ; they are nothing more than mere fibres of con- nective tissue, which have no connection with the chromatophore. Henceforward the chromatophores of the Cephalopoda will not be allowed to form an exception to the general rule that muscular fibres never become inserted into cells, connective or other, and the whole phenomena of their change in coloration will be brought into asso- ciation with what is seen in other forms. Deep-Sea Solenoconcha.*—P. Fischer points out that the mollus- can fauna of great depths is characterized by the great abundance of individuals, but the small number of genera and families; among the Mollusca best represented are the Solenoconcha or Scaphopoda, opis- thobranch and prosobranch Gasteropoda and Lamellibranchs. The first of these seem to be well adapted for living in the bottom of the ocean ; ordinarily without eyes, they capture by the aid of their tentacular filaments the surrounding Foraminifera; they would seem to be present in great numbers, and the best represented species is the Dentalium agile, described by Sars from dredgings in the Northern Seas. A gigantic specimen, dredged by the ‘Travailleur, and now named D. ergasticum, was, when alive, more than 9 cm. long, and its shell is very thick and solid; another, which was probably still larger, cannot be specifically distinguished from an Italian pliocene fossil, and other cases of the same kind lead to the belief that many pliocene fossils supposed to be extinct still live at the bottom of the Mediterranean. Indeed the pliocene Mediterranean must have had a contour and fauna very little different from that of to-day, though there must have been a great difference in the Southern European sea of the miocene period. Vascular System of Naiade and Mytilide.t—In this essay H. Griesbach considers the vascular system and the ingestion of water in some Lamellibranchs. He finds that the peripheral tracts of the vascular system are not closed, but that between the arterial and venous portions there are intercalated spaces without walls or endo- thelium—that is, lacunz in the gelatinous tissue. True capillaries are never found, except in the gills of a few forms, among Lamelli- branchs. The venous portion of the vascular system is complete, and represents the remainder of the ccelom, while the lacunz are ceelom par excellence. The so-called vesicles of Langer, or mucous cells of Flemming, do not exist as such, but are the true lacunz. In the interior, as af the periphery, the vascular system is not closed, but it there communicates with the surrounding medium. The fluid circulated in the vascular system is a mixture of hemal constituents and water. The water enters by the port aquifer, and passes out through the organ of Bojanus. There is no special water-vascular system, but the ingestion is a constant phenomenon. After pointing out the present condition of the question, the author gives a detailed account of the work of his predecessors, and then proceeds to adduce facts in favour of the above-mentioned con- * Comptes Rendus, xevi. (1883) pp. 797-9. + Zeitschr. f. Wiss. Zool., xxxviii. (1883) pp. 1-44 (1 pl.). Ser. 2.—Vot. ILI. Ay 354 SUMMARY OF CURRENT RESEARCHES RELATING TO clusions. Much of what is of value in his history of the vascular system will be found to be due to his recognition of the fact that, in this question, there is a limit to macroscopical inquiries, and that the assistance of the Microscope is necessary. He has thus been able to make out the great size of the so-called capillary tubes. By the aid of experiment he was able to deprive the heart of the greater part of its blood, and to force on himself the question, whither has that blood gone? and in this to convince himself of the presence of hemal spaces in the gelatinous tissue. The blood in the lacunar system would appear to be gradually collected from the most various parts of the body by venous vessels; from the lacune of the foot and of the anterior portion of the mantle, it passes into the truncus venosus, which lies below the rectum, and opens into the pericardium. The veins are true vessels, with a lining of endothelium, but they are not so highly differentiated as is the arterial portion. Although there can be no doubt that the vascular system of Lamellibranchs is, in all its parts, capable of enormous ex- tension, there does not appear to be any sufficient ground for believing that there is a special tissue at the points where this extension more particularly takes place. For this we must look especially to the presence of lacunar spaces. As to the arrangement of these last, it does not seem possible at present to arrive at any generalizations. The author points out the differences between true capillaries and such lacunez as those which he describes. A suitable object for the study of the ingestion is afforded by Cyclas cornea, examined by low power, when placed in a watch-glass. The cilia will be found to be in active movement, working at the respiratory cavity from without inwards, and in a reverse direction at the cloacal orifice. Experiments with carmine will, if rapidly per- formed, make this still more obvious. The author enters into an account of the best way of observing the phenomena, and of the special experiments which he undertook. The Naiadz have three port aquiferi in the foot, and by these the water passes directly into the blood; the slit-like pores in Mytilus and Dryssena lead into a canal-like duct, which is wider in the former than in the latter; in both we find a ciliated cylindrical epithelium surrounding the pore. The duct appears to be nothing more than a lacuna, with which a number of vascular-like lacune are connected, and the whole water-tube is traversed by numerous muscular fibrils, to the presence of which the vascular appearance of the lacune may be ascribed. ‘lhe author believes that this ingestion of water is a true part of the respiratory activity of the Lamellibranchs, and he thinks that, of necessity, the action must be a constant or permanent one. Generative Organs of the Oyster.*—After an elaborate biblio- graphical account, P. P. C. Hoek investigates the structure of these organs in detail. He finds that the reproductive organ of the oyster consists of the genital gland, and its efferent ducts, without any accessory organs. * Tijdschr. Nederl. Dierk. Ver., Suppl. i. 1 (1883) 253 pp. (1 pl.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 355 The gland is not compact and confined to a definite area, but it extends over nearly the whole of the part which may be strictly called the trunk. Separated from the integument by a delicate layer of con- nective tissue, it forms a system of ducts which anastomose with one another, and have their inner wall developed into cecal processes which are set vertically to the surface of the body, and extend into the connective tissue. The genital products are developed on the walls of the ceca, and spermatozoa and ova are developed side by side in the same cecum. They appear to arise from epithelial cells which may be considered as the sister-cells of those which invest the walls of the genital ducts. Their prime origin would appear to be ectodermal, and it is a very difficult matter to make out any mesenchymatous portion. As in other cases, a cell is entirely metamorphosed into an egg-cell, while the spermatozoa arising from one mother-cell form a characteristic ageregation. The ducts of the gland communicate either directly or indirectly with a chief efferent duct, which opens at the anterior termination of a cleft which extends along the muscle of the valves. The organ of Bojanus so far agrees with the genital organ that it is not, as in other Lamellibranchs, compact, but is formed of an assem- blage of ducts and ceca, which form a flattened layer of great extent, but of slight thickness. The wall of the cavity into which the pro- ducts of these two glands open also has an excretory function, and it may therefore be spoken of as the urinary chamber, and its ducts as the ureter. There is no communication between the orifices of the genital and renal organs. The “reno-pericardiac canal” effects a communication between the urinary chamber and the pericardium, and. it seems probable that the auricles have some excretory function. At the time when the ova are laid they are not only fecundated but have passed through the earlier stages of segmentation, but the sperm necessary for this fecundation does not arise from the same oyster. The water which passes over these Molluscs brings from oysters the escaped spermatozoa; some of these pass into the cavity of the mantle, penetrate the generative orifice, and not only make their way into the principal duct, but also into the larger branches connected with it. The oysters of the Eastern Scheldt may have fry in their gills when they are only two years old, but, as a rule, the oysters with fry are older than this, and those of four or five years have the most. Similarly, oysters two years old may produce sperma- tozoa, but as arule, these last arise from older forms. As has already been discovered, oysters of one year may develope spermatozoa, and we find in the Eastern Scheldt that the number of oysters which develope spermatozoa is larger than that of those which give rise to ova. The eggs of a mature oyster are, if properly developed, all laid at once; the spermatozoa seem to be evacuated during a longer period. The evacuation of ova appears to exceed that of spermatozoa. Culti- vation does not show itself favourable to the procreative capabilities of the oyster. In old examples the liver is much more developed than in younger specimens, and this in correlation with the degeneration of the reproductive organs. Pike 2 356 SUMMARY OF CURRENT RESEARCHES RELATING TO Molluscoida. Development of Ova in Ascidians.*—A. Sabatier, who has investi- gated a large number of Ascidians, finds that :— The ovary is composed at first of nuclei arising from the mesoderm and connected together by a small amount of clear intermediate sub- stances. This structure is seen in the adult in those regions of the ovary in which there is a fresh formation of ova. The ovum arises primitively from one of the corpuscles of this tissue, and this, in which one or two granulations appear to form nucleoli, constitutes the nucleus of the future egg. Around this a layer of transparent colour- less protoplasm becomes arranged, and thus the essential elements of the egg are connected together. A delicate membrane, which appears to arise from the intermediate substance of the embryonic connective tissue of the ovary, forms a capsule for the egg. Below this and on the surface of the yolk, cellular elements arise ; these are formed in the yolk and not from outside it. Below them and at their expense is developed a second vitelline membrane. The so-called granular cells are, as Kuppfer and Semper have taught, likewise of vitelline origin ; the intra-vitelline corpuscles are also not immigrated bodies, but they owe their origin to a concentration of granules within the yolk itself. Structure of Ovary of Phaliusiade.j—L. Roule, after stating that he is able to confirm the accounts given by Fol and Sabatier of the ova of Ciona intestinalis, states that the ovules are derived from endothelial cells, which have a protoplasmic layer around their nucleus and an external enveloping membrane ; this last becomes the very delicate vitelline membrane, while the protoplasm and nucleus, increasing in size, form the yolk and the germinal vesicle. The ovules may be found at all stages of development and appear to radiate round a centre of formation. We may then see that the germinal vesicle of young ova contains, in addition to the large nucleolus, two or three smaller nucleoli; in larger eggs there are five or six; gradually these approach the periphery, and appear to pass to the exterior. Those that pass into the yolk may be further traced as cells of the egg- covering, and the testa thus formed may be looked upon as a remnant of the ovular excretion which has produced the follicle ; in some cases the last formed “nuclei” are sufficiently numerous to form a complete layer of the testa, while in others they only produce separate masses. This phenomenon is the cause of variation in the appearance of the ova of different species of Ascidians, and in some cases of different individuals, Embryonic Development of Salpide.t—W. Salensky finds that in the earliest stages the processes of maturation of the ovum of Salpa consists in the shortening of the ovarian pedicle, and in the formation of polar cells which appear before the process of shortening is com- * Comptes Rendus, xcvi. (1883) pp. 799-801. + Ibid., (1883) pp. 1069-72. t MT. Zool. Stat. Neapel, iv. (1882) pp. 90-171 (12 pls.). ZOOLOGY AND BOTANY, MICROSCOPY, ETO. ool pleted. This phenomenon leads to the supposition that fertilization takes place some time after the development of the polar cells, and this view is supported by the fact that spermatozoa only appear in the oviduct when that shortening is over. After the ova consist of four parts the follicular cells begin to proliferate, and completely surround the blastomeres, forming the chief mass of the embryonic cells. In connection with the ovarian products there appears an epithelial investment, derived from the thickened portion of the wall of the respiratory cavity, which, later on, separates into an ectodermal and a placental portion, and plays an important part in the formation of the embryo. Cleavage goes on very slowly; the oviduct continues to shorten, and ends by converting the follicle into a saccular structure, to the inner surface of which the cells become attached. As the oviduct contracts, the follicle passes into the cavity of the ectodermal portion of the epithelial outgrowth, and concludes by completely filling it. After the separation of the epithelial outgrowth has com- menced the wall of the respiratory cavity rises up around its base, in the form of a fold, which later on embraces, with the placenta, the whole of the embryo. The author points out that these results do not agree with those of Todaro,* whose observations he discusses in some detail. The processes just described may be regarded as those of the first developmental period, and we now come to a description of the external _form of the embryo in its different stages. The body is at first pyra- midal in form, it then increases in length and breadth more than in height, and so becomes flattened out; a little later the placenta becomes gradually separated from the embryo, until at last they are only connected together by a short round stalk, which itself finally disappears. Hand in hand with these changes the rudiments of the organs begin to be laid down; the heart appears very early, and the pericardiac cavity is at first very large. The boundaries of the respi- ratory cavity are, at first, very difficult to make out, as it is filled with and lies in a mass of follicular cells. The internal cell-mass is gradually absorbed, when the outer contours of the cavity become, of course, better marked. Simultaneously with the appearance of the egestive orifice we get the first signs of the musculature of the body. This arises in the form of eight muscular bands which commence at the upper end of the body and extend to about its middle. Somewhat later we see the commencement of the ventral folds, which gradually pass into the lower wall of the respiratory cavity. The enteric canal is one of the last organs to appear, and the nerve-ganglion can only be made out with difficulty before it has assumed the form of a vesicle and lost its relations to the outer cell-layers, The eleoblast is not developed early but grows rapidly so soon as it has begun to put in an appearance. The history of these organs is carefully discussed, and several points of disagreement with the accounts given by Todaro appear in its course. - In the latest periods of development we find a thickening of the follicular wall, and the definite formation of the organs. In conse- * See this Journal, iii. (1883) p. 41. 358 SUMMARY OF CURRENT RESEARCHES RELATING TO quence of this thickening the secondary follicular cavity is completely filled by cells, and forms a mass between and from which the muscles and the blood are derived; it may, therefore, be looked upon as analogous to the mesoderm, from which it is to be distinguished by the fact that it takes no part in the formation of the heart. The embryo, at this period, increases in length and approaches its definite form. The preceding observations deal with what has been seen in Salpa pinnata, and in concluding his account of the latest development of the organs, Salensky directs attention to the history of its nervous system, which is important for the early connection which obtains between the rudimentary nervous system and the enteric tract. The history of Salpa africana is not so fully dealt with as that of S. pinnata, but an opportunity is taken to refer to the services rendered by Barrois, and to point out the differences in the two sets of observations. The important, or apparently important, distinction between S. africana and S. pinnata lies in the presence of a body-cavity in the former; this would seem to depend on the greater poverty of cells in part of the mesoderm, and in the absence of that proliferation of the cells of the wall of the follicle to which attention has already been directed in speaking of S. pinnata. In other words, the embryos of S. pinnata are provided with a body-cavity, but it is very early filled up with cells, The paper concludes with a few words on the characters of the placenta, and speaks in terms of approbation of Barrois’ work on this subject. Anatomy and Histology of Brachiopoda Testicardinia.*—J. F. van Bemmelen, after an exhaustive survey of the work of preceding students of this group, deals in detail with the various organs. Treating of the shell, he finds that the perforations in it do not alter with age, and, since new canaliculi are not formed, it follows that the shell of the Brachiopoda does not grow by intussusception, but only at the margin. The so-called shell-papille have often been compared with the vascular outgrowths in the cellulose-mantle of the Tunicata, but as the spaces in the former do not communicate with the vessels in the mantle, it is obvious that no close comparison is possible between the two sets of organs. The shell of the Brachiopoda is only a cuticular structure, comparable to that of Annelids and Arthropods, and is not of the same nature as that of the Mollusca, which arises from a shell-gland. The proper body-wall is to be distinguished from the mantle ; the ectoderm forms a single layer of epithelial cells which have large nuclei, but are themselves relatively small. The layer of connective tissue consists of a true supporting substance lying between the ectoderm and the parietal mesoderm; varying in thickness, according to its relations to different organs, it has always a homoge- neous structure with interspersed connective-tissue cells. Distinct bands of tissue are to be made out in some genera, but they all seem to be nothing more than differentiations of the homogeneous supporting * Jen. Zeitschr. f. Naturwiss., ix. (1882) pp. 88-161 (5 pls.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 359 substance ; and this remark applies even to the “ stalk.” The compli- cated lacunar system, described by Hancock, would appear to be merely due to the mode of connection of the stellate connective-tissue cells ; and this is the more probable as an explanation, since Hancock, in his very careful account, never mentions the connective-tissue elements. 'To the author just mentioned we owe our first exact know- ledge of the nervous system of this group. On either side, the wall of the pharynx gives rise to a fold which carries the cesophageal ring; below the pharynx is the ventral ganglion, in which we find two continuous lateral aggregations of ganglionic cells, connected with one another by nerve-fibres. From this there is given off, on either side, a thick nerve which at once divides into two branches; one of these, the thicker, passes to the dorsal half of the mantle, the other {and thinner) to the commissure. The lateral commissures curve over in front of the pharynx, towards the body-wall, and thence pass into a nerve-cord, which extends into the walls of the arms and expands, above the mouth, into a ganglion. It follows, therefore, that there are supra-cesophageal arm-nerves, and these are much larger than the sub-cesophageal. After describing the minute structure of the parts of the nervous system, the author passes to the genital organs. Here, again, we find the remarkable researches of Hancock duly noted; but the more modern author has been able to make out that there is no sharp distinction between the epithelium of the body- cavity and the ovarian cells; and that, therefore, the ova of the Brachiopoda may be said to be metamorphosed ccelomic cells. It is true also of the spermatozoa that they arise from a germinal epithelium which is directly continuous with the epithelium of the body-cavity. This ccelom is lined by a single layer of flattened epithelial cells, and the genital glands are placed in folds of the sup- porting substance, in which cavities are developed. It seems certain that the Brachiopoda Testicardinia have the sexes separate. The muscles consist of parallel simple fibres of contractile sub- stance, which for the most part are not connected together, and which apparently extend through the length of the whole muscle. Nuclei are to be found on their outer side, and these are surrounded by a very small amount of granular protoplasm. ‘The only difference between the plain and striated muscles is to be seen in the structure of the latter. Coming to the discussion of the systematic position of these difficult forms, the author finds that, in the histological structure of their body-wall, musculature, and genital organs, they present all the characters of the Enteroccelia of the Hertwigs; the mesenchymatous layer is but feebly developed. Instead of being allied to the Mollusca, they appear to present the closest resemblance to the Chetognatha. Not only do the ectoderm, the enteric canal, and the body-cavity present just the same develop- _ mental history, but in both we observe a feeble development of connec- tive tissue; the only differentiation in this layer is the formation of supporting fibres. Further, we find that epithelia are always simple, and the generative products are directly produced from one of them 360 SUMMARY OF CURRENT RESEARCHES RELATING TO A similar kind of agreement is to be seen in the minute structure of the nervous system; in both the ganglia are made up of simple small nerve-cells and nerve-fibres ; the latter alone form the peripheral tracts, and these are simple flat bands. The resemblance in the mode of forming plexuses is no less striking. ‘The nervous plexus under the ectodermal epithelium of the arms of the Brachiopoda is to be compared to the stellate ganglionic cells connected with the neighbour- ing nerve-trunks which are to be found under the epidermis of the Cheetognatha. As is well known, both the groups under discussion exhibit the formation of an enteroccele; both present a very symme- trical structure, and have a spacious celom. The segmentation into three metameres in the Brachiopoda is, in the adult, exhibited by the gastroparietal and ileoparietal bands; in both groups the second and third metameres stand in relation to the reproductive organs. The vasa deferentia of the Chetognath belong as much to the type of seg- mental organs as the infundibular ducts of the Brachiopod. In both groups we find the enteric canal supported by dorsal and ventral mesenteries ; in both, the central organ of the nervous system consists of an cesophageal ring with an upper and a lower pair of ganglia. From the latter arise two large nerve-trunks which pass backwards and branch largely, without, however, giving any signs of a ladder- shaped nerve-cord. The upper ganglion of the Brachiopod inner- vates the arms and that of the Chetognath the short tentacles. Though there is a difference in the characters of the sensory organs, there are indications of a degeneration of these parts in the Brachiopod, The important differences are the possession by the Brachiopod of a shell and of a stalk; but the former has been shown to be merely a thickening of the cuticle, and the secondary value of the latter is spoken to by the differences between the Testi- and Ecardines. Arthropoda. a. Insecta. Early Developmental Stages of Ovum in Insecta.*—Dealing first with the Hymenoptera, A. Weissmann finds that in Rhodites rose the shell of the mature egg is provided with a long peduncle; the germinal vesicle is replaced by a transparent nucleus, the first seg- mentation-nucleus, devoid of a membrane. The yolk contracts, and the nucleus becomes a whitish streak, which divides into two halves; these shorten, constituting the “polar nuclei” of the author; they perform amceboid movements; the posterior nucleus gives rise, by elongation and fission, to about thirty nuclei. The nuclei now migrate to the periphery and become surrounded by the yolk, which forms a superficial layer to the ovum, and soon assumes a cellular character, forming the blastoderm, the cells of which are uniform in character, and all have a large nucleus directly invested by deutoplasm- granules; the periphery of the cell is formed of clear protoplasm. The anterior polar nucleus buries itself in the yolk at the period at * Beitrage z. Anat. u. Physiol. als Festgabe Jacob Henle, Bonn, 1882. Cf. Rey. Sci. Nat., ii. (1882) pp. 135-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 361 which the nuclei derived from its fellow migrate to the circumference ; it then divides in the same manner as the posterior nucleus, pro- ducing a long line of nuclei, which are directly invested with proto- plasm, and constitute the vitelline cells. The blastoderm of the ventral aspect thickens, forming the ventral plate, while it becomes attenuated dorsally ; the amnion makes its appearance as a single fold or prolongation of the dorsal part of the head end, consisting of a single layer of cells extending round to the ventral side. Shortly after the amnion is formed, the germinal plate becomes grooved by a transverse linear furrow, which, after deepening, remains stationary for a time, and then disappears; it is considered by Weissmann as a gastric in- vagination homologous with the longitudinal groove found in other insects. The mouth and cephalic constriction then appear, and a little later the proctodeum. At first sight the mesoderm seems derived wholly from the so-called vitelline cells; but in reality it is derived from certain globose cells from the middle of these, behind the transverse groove and near the anterodorsal aspect, which become detached, and range themselves below the blastoderm as a definite layer. : The mesenteron is bounded by large granular endodermic cells which inclose the remains of the yolk. At the moment of hatching the larva has thirteen segments; it cannot be determined whether the anterior division corresponds to a single segment, or to the whole head, as in all insects but the Muscide. Three pairs of tubercles, placed behind the mouth, are the rudiments _ of the mouth-organs: the first pair form the mandibles; the second, which become rudimentary, represent the maxillary palps; the third pair fuse into a median plate, which protects the mandibles. The antennee appear as tubercles on the procephalic lobes, and remain in this condition during larval life. No trace of limbs occurs on the segments of the body at any stage. Biorhiza aptera differs from Rhodites in developing a vitelline membrane; as in Rhodites, the yolk penetrates into the peduncle of the egg, but it is retracted again. The first segmentation-nucleus — lies in a transparent mass of protoplasm situated at the anterior pole; after performing amoeboid movements, it elongates in a transverse or oblique direction, and divides into the two polar nuclei, and almost immediately after this the posterior of the two itself begins to divide, while the anterior remains for a time inactive, and then divides; the two sets of nuclei derived thus are indistinguishable. It appears that when about 100 nuclei have been thus formed they become the centres of cells, part of which move to the surface and form the blastoderm. The anterior cells of this membrane emit slender anastomosing pseudopodia like those of Radiolaria, which project into the space beneath the vitelline membrane, but disappear after a short time. The amnion is formed as in Rhodites; no gastric invagination has been observed; the development of the segmental appendages cor- responds with that of Khodites, and here also there are no thoracic appendages ; the small anterior segment of the larva represents the entire head. 362 SUMMARY OF CURRENT RESEARCHES RELATING TO Diptera.—In Chironomus sp. the freshly laid ova show a con- siderable contraction of the yolk to have taken place ; a superficial layer of protoplasm is also distinctly differentiated. Before the formation of any traces of a blastoderm, masses of protoplasm, with or without nuclei, become detached (usually at the anterior pole), and subdivide, thus forming polar globules. Later are formed the polar cells, a mass of twelve cells, at the posterior pole. The plasmatic cortex is now occupied by nuclei, and takes on a cellular character, forming the blastoderm; after this an anterior nucleus buries itself in the vitellus, and there divides, as in Rhodites. Orthoptera—In Gryllotalpa the ova are large, and there is no plasmatic cortex. Cells composed of clear protoplasm are found in the yolk soon after fertilization; they make their way to the surface and there divide, forming islands of smaller cells; these islands become connected together, and eventually form a continuous blasto- derm. Three types of blastoderm formation are distinguished in the above insects. 1. Gryllotalpa.—Ova large; cells appear in yolk and pass to the surface. 2. Rhodites, Biorhiza.—F ree nuclei pass to the surface and there collect around them cell-bodies rich in nutritive yolk. 3. Chironomus.—The nuclei pass to the surface, to find there a layer of protoplasm already differentiated. 4, The Poduride present a fourth case. The small ovum forms a blastodermic sac by total segmentation. It is noteworthy that the nuclei form no karyokinetic figures in the process of division; their amceboid movements have a purely nutritive object ; the nuclei are not necessarily centres of attraction for proto- plasm, for they remain for a considerable period independent of any cellular bodies. Innervation of the Respiratory Mechanism in Insects.*—Dr. O. Langendorff denies Dénhoft’s statement that respiratory movements in insects cease after decapitation. Experiments on humble-bees, wasps, cockchafers, and dragon-flies, show that these movements con- tinue in the abdomen after removal of the head, and even of the thorax. Indeed, in some cases, sections of the abdomen of a dragon- fly, as small as one ring and a half, continued the rhythmical respira- tion. It is therefore evident that the nerve-centre for respiration is not in the head. A decapitated cockchafer breathed for an hour. Heat was found to increase the activity of respiration in mutilated as in healthy individuals. Graphic illustrations are given of normal respiration, and compared with those obtained from decapitated specimens. Histology cf Insect Wing-muscles.t—G. V. Ciaccio finds that in most insects the wing-muscles may be decomposed into fibrille (in others, into striated fibres: Sphinx, Libellula, &c.), In the former * Arch. Anat. u. Phys., 1883, p. 80. See Science, i. (1883) pp. 316-7. + Arch. Ital. Biol., ii. (1882) p. 131. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 363 case the fibrille are united into bundles of various sizes by a cement- ing substance, in which the nuclei lie either both in the interior and upon the surface of the bundle (Hydrophilus, Dytiscus), or upon the surface only (flies). The bundles are held together by tracheex, and sometimes also by fat-cells. In the cement, further, are always found distinct particles (Aubert’s masse grumeleuse interfibrillaire), which do not occur in the other muscles. The fibres are composed of fibriJle, and have nuclei either upon the surface (Cicada) or in the middle (Libellula). In some insects the fibrillz are arranged as in a folded lamella, the leaves of the folds running out from the centre of the fibre towards the surface, seen in cross-sections. The nerve-fibres terminate in motor plates (probably several for each fibre), consisting of a granular basal substance, in which are imbedded the ramifications of the axis-cylinder. The wing-muscles are more readily dissociated into fibrillee than those of the rest of the body, from which they are further differentiated by the absence of a true sarcolemma. Flight of Insects.*—M. Amans thinks that in the theories of artificial wings, propounded by Marey and Pettigrew, both observers have failed to see that the base of the wing is formed of two planes set af an obtuse angle in such a way that, when the wing is descending, the posterior plane presents its concavity to the column of air struck. The author has made some anatomical observations on Aischna, Siren, and Locusta, which seem to confirm his view. Locomotion of Insects on Vertical Glass Surfaces.t—H. Dewitz supports the explanation already advanced by Blackwall of this pheno- menon, viz. that a glutinous liquid is exuded from the apices of hairs which surround the lobes of the feet. He resorts to direct observation of the living insect, fixing it feet uppermost to a glass slide which is placed under the Microscope. By this means the ends of the hairs surround- ing the lobes of the feet are seen to emit a transparent substance by which the foot adheres to the glass ; if the foot is then drawn away, drops are seen to be left on the glass, corresponding in position to the hairs of the foot-lobes. In cases where there are no hairs, as in the bugs, the adhesive material proceeds directly from pores in the foot. Many larve (e. g. Muscide, the alder-leaf beetle, and the saltatory Dipterous larve) use a similar substance in their movements, pro- bably also half the total sum of perfect insects, including most Diptera and Hemiptera, many Hymenoptera and Coleoptera, and probably those Orthoptera which neither leap nor fly. The same author t has examined the structure of the foot of a beetle, Telephorus dispar, and other insects with the same object. The hairs on the foot run out to sharp points, below which are placed the openings of the canals. The glands are chiefly flask-shaped unicellu- lar organs, lying in the hypodermis of the chitinous coat ; each opens into one of the hairs; they are each invested by a structureless tunica propria, and they contain granular protoplasm, a nucleus placed at * Comptes Rendus, xevi. (1883) p. 1072. + SB. Ges. Naturforsch. Freunde (Berlin), 1882, pp. 5-7. { Tom. cit., pp. 109-13. 364 SUMMARY OF CURRENT RESEARCHES RELATING TO the inner side, and a vesicle, prolonged into a tube which, traversing the neck of the gland, is attached to the root of the hair; the vesicle receives the secretion. Each gland is connected with a fine nerve- twig. Secretion is probably voluntary. In Telephorus this power is soon weakened and not rapidly renewed. Among the adhesion-hairs are distributed others, supplied by nervous twigs; a ganglionic swelling is placed just below the end of each of these. On the hairless globular tarsi of many Orthoptera almost all the cells of the hypodermis of the sole form unicellular glands ; each sends out a long fine chitinous tubule, which is connected with its fellows by very fine hairs and is continuous with the chitinous coat of the foot and opens through it. Thesole of the foot is elastic and adapts itself to minute inequalities of surfaces; the interior of each tarsal joint is almost entirely occupied by an enlargement of the trachea, which acts on the elastic sole like an air-chamber, rendering it tense and at the same time pliant. The apparatus found on the front legs of the male of Stenobothrus sibiricus must have the function of causing the legs to adhere closely to the female by the excretion of an adhesive material ; gland-cells and enlarged trachez are found here also. The hairs of the anterior tarsi of male Carabi appear also to possess the adhesive function. The adhesion of pollen to bees appears to be similarly effected. The excretion is effected from the glands in Telephorus by contraction of the protoplasm, which when the parts are teased in in- different solutions exhibits active movements; the secretion has been seen to be driven from the internal vesicle into its neck ; many facts as to vital contraction are given in support of this view of the cause of the exudation of the glutinous matter. Salivary and Olfactory Organs of Bees.*—P. Schiemenz in this elaborate paper commences with the ordinary bibliographical résumé ; he describes in detail the structure of the parts of the digestive tract which bears on the question of the salivary glands, and discusses their developmental history and their function. He points out that all glands have to supply a secretion, and that the more the separate cells take a larger share in this, the richer the secretion from a smaller number of secreting cells. In bees there are two essentially ditterent modes by which this is effected, and the two types may be appropriately spoken of as the intracellular, and the intercellular. In the simplest case of the latter we find a sac lined bya simple layer of cells, so arranged that each cell presents a proportionately broad surface to the common cavity ; the material is obtained from the blood at the opposite ends of the cells. If the sac elongates, its diameter diminishes and we get the tubular form. In these two “systems ” the cells are widest in a direction parallel to the lumen of the sac or tube. If the cells become spheroidal, there is a proportionate diminution in the secreting surface, and efferent canals appear between the cells. As a matter of fact, glands of this kind of construction do, among the Apide, stand remarkably close to the saccular or the tubular. * Zeitschr. f. Wiss. Zool., xxxviii. (1883) pp.-71-135 (3 pls.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 365 The intracellular type obtains in what the author calls his first, fourth, and fifth systems ; here the cells are attached to long stalks and float in the coelom; and thus it happens that the whole of their surface is able to take up the necessary matter from the blood. In connection with the consequent large secretion, secretory canaliculi are developed, which make their way into the cells, surround the plasma, and so afford a correspondingly large surface for excretion. To this type a much greater secretory activity must be ascribed than to that in which secretion is intercellular. In the so-called fourth system we find that the intercellular spaces are very rare, and in the first (Bombus) the free cells are arranged inacini. Both these arrange- ments must be due to the large number of cells present. The author concludes that the so-called crop has, in honey-bees, the function of, at times, completely shutting off the honey-stomach from the chyle-intestine, while the small intestine forms the means of com- munication between the latter and the rectum. ‘The salivary glands vary considerably both in genera and species, and it seems probable that their functions are also very varied. While one system of glands is formed within the propria of the first portion of the larval spinning- glands, two others are derived from its efferent canals, and the other two are fresh structures formed by an invagination of the epidermis, The olfactory mucous gland of Wolff is salivary in function. Mimicry of Humming-birds by Moths.*—The striking resem- blance in size, form, and movements, of the South-American Macro- glossa Titan to humming-birds, which has been noticed by Bates, Fritz Miller, and others, and referred to the similarity in their habits, is believed by Dr. Krause to be a case of protective mimicry, the moths benefiting by their resemblance to the birds, which have few winged enemies. The closeness of the resemblance is supposed also to protect the moths from the humming-birds, which always give chase when they recognize them. ‘To do away with an objection that might be urged from the similar appearance of European Macroglosse, which have no Trochilidz to imitate, it is assumed either that these birds occurred in Europe in late tertiary times, or that the moths are recent importations from the new world. 8B. Myriopoda. Systematic Position of the Archipolypoda.t—Dr. A. 8. Packard, jun., has some observations on the recent paper by S. H. Scudder on the Archipolypoda, a group of fossil Myriopoda, from the Carboniferous formation. These forms had a fusiform body largest near the middle of the anterior half or third; the head appendages were carried on a single segment. Connected with each of the ventral plates of the other segments are a pair of long jointed legs, with large spiracles outside them; the mouth isset transversely. Dr. Packard has lately been studying the Lysiopetalide, ‘“‘a rather aberrant and synthetic family of Chilognatha,” and he points out that Scudder must. have had, * Kosmos, Nov. 1882. Cf. Science, i. (1883) p. 203. t+ Amer. Natural., xvii. (1883) pp. 326-9. 366 SUMMARY OF CURRENT RESEARCHES RELATING TO in his comparisons, the Julide in view, as some other Chilognaths have a fusiform body. He doubts the accuracy of the statement that the head appendages are carried on a single segment. The legs are a little longer than in the Lysiopetalide, and several of the characters indi- cated are to be found in them also. Owing to the possession of spinulate spines the fossils have a somewhat remarkable appearance, but an approach to them is probably to be found in the barbed set on the segments of the embryo Strongylosoma, and in Polyxenus fasciatus. Dr. Packard thinks that the fossils form a group nearly equivalent to the Lysiopetalide, but below them. They are truly of an ancient type, as is shown by the retention and enlargement of the spiny sete which occur in embryonic and larval Chilognaths, and by the presence of a pair of spiracles on each segment (and not on alter- nate ones, as in Chilognaths and Chilopods). The characters of their appendages are in keeping with this view. The legs would appear to have had sharp claws, and there is no evidence to justify us in thinking that they were swimming organs. The peculiar organs regarded by Scudder as supports for branchie are, in Packard’s opinion, suggestive of this idea, and “it is to be hoped that fossils will be discovered, with remains of the branchiz themselves; though it is hard to see how they could have been associated with such large spiracles.” Dr. Packard would divide the order of Chilognatha into two sub-orders, one of the Archipolypoda and the other of Chilognatha vera. In the latter the possession by each segment of two pairs of legs is a secondary and acquired character. A parallel may be found in the Phyllopod Crustacea, where “ from two to six pairs of legs in post-larval life arise from a single segment.” Anatomy and Development of Peripatus Capensis.* — Prof. F. M. Balfour’s memoir on this species (a preliminary note of the em- bryological portion having already appeared) is now published, edited by Prof. H. N. Moseley and Mr. A. Sedgwick, and illustrated by eight beautifully executed plates. The more important facts of the early development of Peripatus Capensis are as follows:—1. The greater part of the mesoblast is developed from the walls of the archenteron, 2. The embryonic month and anus are derived from the respective ends of the original blastopore, the middle part of the blastopore closing up. 3. The embryonic mouth almost certainly becomes the adult mouth, i.e. the aperture leading from the buccal cavity into the pharynx, the two being in the same position. The embryonic anus is in front of the position of the adult anus, but in all probability shifts back and persists es the adult anus. 4. The anterior pair of mesoblastic somites gives rise to the swellings of the pre-oral lobes and to the mesoblast of the head. It is intended that the present memoir should be followed by others, comprising a complete account of all the species of the genus Peripatus. * Quart. Journ. Micr. Sci., xxiii. (1883) pp. 213-59 (8 pls.). + See this Journal, ante, p. 52. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 367 New Species of Polydesmus with Eyes.*—The species of Poly- desmus, a genus embracing some of the most common Myriopods, are, as a rule, eyeless. Dr. A. 8. Packard, jun., has, however, found at Portland, in Oregon, a form in which eyes are present. The characters in general are such as not, perhaps, to warrant a separation from the genus, and he proposes to name it P. ocellatus. It might be easily mistaken for a T'richopetalus. The individuals were mature, or nearly so, as they were horn-brown. The 12-13 ocelli were conspicuous and black. In the cylindrical body and thick antenne it approaches P. cavicola Pack., from a cave on the shores of the Great Salt Lake. It differs from that species, which is eyeless, in the fusiform body, much thicker antenne, and the finer granulations as well as the larger number of segments. 6. Crustacea. Caprellidet—P. Mayer commences with an account of the systematic characters of these Crustacea, reviewing the work of his predecessors, and showing how these have advanced the study of the group. An account of the families, genera, and species then follows, more especial attention being, of course, given to the forms found in the Bay of Naples. This section concludes with an alphabetical list of the genera and species. An account of the little that is known as to the geographical distribution then follows; and this is succeeded by a series of chapters on the anatomical and histological characters. The difficult question of the relation of the Caprellide to the Cyamidz is in conclusion discussed, though we have no paleontological and but little embryological evidence to assist us. Some answer, how- ever, must be given to the question: Are the Cyamide really allied to the Caprellide, and is the group of the Lemodipoda a natural one? We find that the external and internal organization of a Cyamid is similar to that of a Caprellid; in both the abdomen has undergone a like kind of degeneration, and there is much in common in the characters of the liver, the external generative organs, and the general segmen- tation of the body. The group, then, of the Lemodipoda being a natural one, we have to see whether the ancestor of the group stood closer to the Caprellidz or the Cyamide. ‘The result of the inquiry is in favour of the former, and leads to the view that the latter were derived from a form not unlike Caprella. The genus Platycyamus appears to be a very lately developed Cyamid. The Lemodipod ancestor seems to stand in closest alliance to the Gammaride amongst the Amphipoda, but the cause of the peculiarities in its organization cannot be certainly defined; there is not as yet sufficient evidence to justify us in ascribing it to their more sessile mode of life. Coloration of Idotea tricuspidata.t—C. Matzdorff divides his essay into three portions; in the first or descriptive part he gives an account of the coloration of these Isopods, which he arranges in five * Amer. Natural,, xvii. (1883) pp. 428-9 (6 figs.). + Fauna u. Flora des Golfes Neapel, vi. 4to, Leipzig, 1882. 201 pp. (10 pls. and 39 zincographs). } Jen. Zeitschr. f. Naturwiss., ix. (1882) pp. 1-58 (2 pls.). 368 SUMMARY OF CURRENT RESEARCHES RELATING TO groups; in the first all the examples have the same colour, whatever that may be; in the second we have those with bright lateral bands, and a broad dark median band; in the third there are bright lateral bands, but there is a delicate white median one, and between it and each edge there is a broader dark longitudinal band; in the fourth group the examples are spotted, and in the fifth there is a kind of transverse striation. In some rare cases individuals were observed which could not be brought into any one of the above categories. The separate groups are fully described. In the second or anatomical portion an attempt is made to bring these colours into relation with histological characters; it has been found that all green or greenish colours are not due to the animal itself, but to lower alge; similarly diatoms influence the coloration in the direction of yellowish-brown, but other animals, such as the Infusoria under the carapace, do not appear to affect the appearance of the animal. The reddish or greenish-grey colours seen along the median line are due, not to the tissues of the animal, but to the vegetable remains in their intestine. The unpigmented or non- coloured spots are referable to the histological elements; if pale yellow or reddish they have been affected by the chitin; oil-drops in the hypodermis give rise to a yellow coloration. White, red, and brown bands are to be referred to the chromatophores in the hypo- dermis ; these consist of an upper layer of chitinogenous cells and of a lower layer formed of a granular protoplasmic mass with nuclei regularly distributed, but without cell-walls. The chromatophores, which are regularly arranged, have a diameter of from 60 to 80 uz They clearly belong to the series of amceboid cells, and though two kinds of them can be distinguished they are histologically equivalent to one another. In the third, or physiological. section the author discusses the influence of the constituents of the environment; he finds that food has no influence on the coloration, while temperature is frequently seen to be of importance. Light, of course, is still more a factor, while the proportion of salines in the water often greatly affects the form, size, and coloration. As to the coloration itself, we may see that there is no proof of any warning or protective aim, nor does sexual selection seem to have been of any influence. All the colours and markings of [dotea must be regarded as being sympathetic and referable to adaptations to environment, The colours are found to change rapidly, stages from bright yellowish-brown to dark brown succeeding one another in one and the same animal; or there may be a direct passage from a light to a dark shade; brightly coloured specimens, placed in dark vessels, gradually dilate their chromato- phores, while dark examples placed in white porcelain vessels contract their colouring cells. The white chromatophores change less rapidly, and moreover function in an opposite sense to the dark ones, for they dilate when the animals become lighter, and contract as they become darker. The change in colour appears to be associated with the presence and functional activity of the optic organs. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 369 The author discusses the advantages and characteristics of the different kinds of coloration, and concludes by suggesting that the phylogenetic development of the separate varieties is to be explained by supposing that the unicolor examples are the oldest. When the dark contents of the intestine became apparent, “ white chromato- phores ” must have been developed. Bands would appear in relation to a habitation among marine grasses, and doubly-banded forms would imitate the marking of the Zostera-leaves. A further change of environment would add to the advantage of the possession of spots in the markings. Vermes. Annelids of the Canary Islands.*—P. Langerhans has some observations on the anatomy of Syllidesw, where he has found in all species of the genera examined a canal in the strong cesophageal teeth ; in Syllis aurantiaca he has been able to make out the poison-gland, which is a paired tube lying dorsal of the cesophagus. He has studied the process of reproduction by fission, and has addressed himself to the question as to whether the same individual once or repeatedly produces, asexually, sexual forms. The result is in favour of the latter, or Krohn’s view; the time between the productions varied from 25 to 49 days, but he never observed the production of more than two sexual forms. Each bud, as it broke away, carried with it a number of the parent-segments; nearly all the segments of the new person contain generative products. There does not seem to be any difference between males and females, but three forms of head are to be distinguished. Of the 57 species noticed 9 at most are new. Anatomy and Histology of Terebellides Stroemiit—J. Steen, in describing the cephalic region of this annelid, says that it is extremely interesting to observe under the Microscope the working of the delicate tentacles; they are pushed out in all directions, and may become extended so much as to be longer than the body. They carefully test all the bodies they desire before they seize them. They are provided with a delicate cuticle, below which is an hypodermis, consisting of elongated cylindrical cells. Below these there is a thin transversely striated membrane, comparable to the supporting lamella of hydroid polyps. Below this, again, are the longitudinal muscles, separated by interspaces of various sizes. ‘The spaces thus included are filled by a plexus of connective tissue, and the separate fibres are thickened at various points, and are provided with distinct nuclei. The transverse dissepiments, seen by M‘Intosh in the tentacles of Magelona, could not here be detected. After some account of the thoracic and abdominal regions, and a description of the characters which distinguish Terebellides from Terebella, the author passes to his histological observations. The dermo-muscular tube consists of the ordinary four layers ; * Nova Acta -Acad. Caes. Leop.-Carol., xlii. (1881) pp. 95-124 (2 pls.). + Jen. Zeitschr. f. Naturwiss., ix. (1882) pp. 201-46 (3 pls.). Ser, 2.—Vot. III. 2B 370 SUMMARY OF CURRENT RESEARCHES RELATING TO no pores could be detected in the hyaline cuticle, nor were the rod- shaped or spindle-like structures which are so often to be made out in the hypodermis of Annelids detected in this form. In correspond- ence, possibly, with their tubicolar habit, the muscular layers are not thick; the division of the body-cavity into three longitudinal chambers, owing to the development of muscular plates, such as has been signalized by Claparéde in various Terebellae, could not be here demonstrated. The ccelom is well developed, especially in the more anterior regions, but the so-called dissepiments marking off the separate seg- ments were not observed. The body-cavity is continued not only into the parapodia, but also into the lobes of the head, the gills, and the filiform tentacles ; with the exception of the first, the outgrowths are traversed by a connective-tissue plexus. A large lacuna at the base of the tentacles supplies those organs with fluid, and they then become extended. The general cavity is filled with a colourless fluid, which exhibits a constant lively movement, not marked by any regularity in direction. A number of discoid elliptical corpuscles, which are never coloured, are always to be found in it. The liver is made up of lamellee, which are set longitudinally, and it has the same cylindrical epithelial cells as the cesophagus; the muscular stomach is regarded as being homologous with the similarly named organ in Iumbricus ; sections made across the anterior portion of the intestine (or “hindgut”) exhibit the presence of a number of inwardly pro- jecting folds, the largest of which is to be seen on the dorsal side; these folds are richly provided with blood-vessels, and when the dorsal vessel becomes smaller and divides into two, as it does in the 22nd segment, the folds become proportionately smaller. The author takes the same view as Claparéde with regard to the tubicolar functions of the salivary glands. The “ventral medulla” is intermediate in character between {the step-ladder form, seen in Serpulide and others, and the fused cord found in Scoloplos, for here the two longitudinal cords are only sepa- rated by a connective-tissue sheath ; in the hinder portion of the body it passes into the hypodermic area. Special ganglionic enlargements are not developed in each body-segment. Unlike what obtains in the earthworm, but just as in the oligochetous Enchytreids, the investing membrane consists of a homogeneous, and not striated, neurilemma, but there does not appear to be any cellular structure in this neurilemma. The most conspicuous portions of the blood-vascular system are the two large dorsal and ventral vessels, and, in addition to these two, there are two longitudinal vessels on either side of the body; of these the upper is more delicate than the lower. The blood is corpus- culated ; the corpuscles being numerous, and of an elliptical form. The females appear to be more numerous than the males, and are distinguished by their yellowish-green colour; the ova are developed in a tissue of the segments, which seems to be homologous to the ovaries described by Grube in the Terebellide, The germinal ZOOLOGY AND BOTANY, MICROSCOPY, ETC. O71 vesicle is of some size. The spermatozoa, like the ova, are developed in large masses, and, like them, pass into the spaces in the thoracic parapodia. They are generally found aggregated, and separate spermatozoa are but rarely detected; they resemble in form those of Magelona. The segmental organs are confined to the 5th and 6th segments, and serve as efferent ducts for the genital products; they consist of an infundibular and a spherical portion, and the cilia are confined to the former. The latter apparently serves as the secreting organ of the matter by means of which the genital products become attached. The external pore resembles that seen by Cosmovici in Pectinaria. Exogone gemmifera.*—C. Viguier, after a brief account of the work of Pagenstecher and others on this annelid, states that he has frequently found both males and females in the sexual condition ; some of these have, and some have not seta, so that the view of Pagenstecher that the asetal forms are agamic, and the setose sexual is not confirmed ; so, again, H. martinsi may or may not have long sete. The author enters into some detail with regard to the history of this development, as this form has served as the basis of Pagenstecher’s doctrine of lateral buds; such an exception to the general rule that germination takes place in a longitudinal direction deserved recon- sideration ; and the author proposes to deal fully with the matter in a more extended memoir, Structure and Development of Phoronis.t—W. H. Caldwell, in a preliminary note on this Gephyrean, points out that the epistome lying in the short line between the mouth and anus is the persistent pre-oral lobe of the larva, and that this line is the median dorsal line. The ventral surface is produced into a foot, which constitutes the main part of the animal. The central nervous system retains its primitive epidermic condition, and concentrations take place round the mouth to form a post-oral nerve-ring ; in front of this are situated a pair of sense-organs, which may be spoken of as the “ ciliated pits” ; the protuberances in Rhabdopleura, figured by Sars, may be their homologues. The body-cavity is divided by mesenteries into three chambers, and there is, further, a septum which passes from the line of the nerve-ring into the cesophagus. The genital pores of Kowa- levsky are the external openings of a pair of nephridia, each of which consists of a simple ciliated tube, the cell-walls of which are filled with brown concretions. These tubes open into the posterior chamber of the body-cavity. There is a closed system of blood-vessels, con- taining nucleated red corpuscles, and the walls of all the vessels are contractile. The sexes are united in the same individual, and the generative products are formed from cells of the efferent blood-vessel which runs in the left anterior chamber of the body-cavity, and the generative cells, like the nerve-cord, are asymmetrically placed. * Comptes Rendus, xcvi. (1883) pp. 729-31. + Proc. Roy. Soc., xxxiv. (1883) pp. 371-83. 2832 372 SUMMARY OF CURRENT RESEARCHES RELATING TO In the history of development we see that segmentation is unequal, and that the gastrula is invaginate ; the mesoblast is formed bilaterally from the endoderm on either side of the blastopore; from the time when two or three mesoblast-cells are budded off on either side a cavity is present in each mass so formed ; these cavities are the two halves of the body-cavity, and the author regards the mode of origin as a modification by simplification of the enteroccel type, as seen in Argiope. The mesoblastic diverticulum into the pre-oral lobe grows rapidly, and distinct somatic and splanchnic layers soon become apparent; the muscle-cells in this region have all the histological character of the mesenchyme of the Hertwigs. The endoderm becomes thickened in the pre-oral lobe to form the future nerve-ganglion, and as a post-oral ring indicating the position of the line of future ten- tacles in the circumcesophageal nerve-ring of the adult. The anus is, from the first, terminal in position, and the four divisions of the alimentary canal early become apparent; the cells of the first stomach, though ciliated, are much more ameboid than in the adult, and throughout larval life digestion goes on in this region. The whole mesoblast arises as two endodermic sacs, the walls of which form somatic and splanchnic layers. The vessels were seen to arise as splits in the splanchnopleure. The author is of opinion that the life-history of Phoronis offers a solution of many morphological problems; the pre-oral ring, corre- sponding to the velum of a Trochosphere, is from the earliest stages reduced relatively to the post-oral; the latter persists throughout life as a cireumcesophageal ring; the ganglion of the pre-oral lobe disappears with the change from a free to a fixed mode of life. The whole body-cavity is an enteroccel; the intracellular portion of the excretory system atrophies when the vascular system is developed. The identity of the Phoronis-larva, up to the formation of the nephridia and before the outgrowth of the anal region, with the Tro- chosphere-type of Hatschek is complete; the distinction drawn by the brothers Hertwig between the histological characters of the mesen- chyme and mesoderm utterly breaks down in Phoronis, and it may be suggested that the other Trochospheres are enteroceeles. The author discusses briefly the relations of Phoronis to the Brachiopoda and Polyzoa, and suggests that the larve of these forms are modified from the Trochosphere by the earlier attainment of the relation of the ventral surface which in Phoronis is only accomplished during the metamorphosis. Development of Borlasia vivipara.*—W. Salensky finds that, though the males are much smaller than the females, the generative organs are in both sexes formed on the same type, being constituted by paired sacs which open to the exterior by pores at the sides of the body. These sacs are lined by a secretory epithelium, the ovum is fertilized in situ, and there remains till the larva is developed. Seg- mentation is complete and unequal, and before the blastula is con- * Bull. Sci. Dép. Nord, v. (1882) pp. 462-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 373 verted (by invagination) into the gastrula, a certain number of meso- dermic cells put in their appearance. The position of the blastopore is with difficulty distinguishable, and its ultimate fate is unknown. The anterior end is early distinguished by a small ectodermal thickening, which is the rudiment of the future cerebral ganglion. This thickening soon separates from the ectoderm and takes on the form of a transversely widened plate, soon to be distinguished into two halves. At the inferior pole a mass of cells begin to give rise to a pyri- form organ, which is, physiologically, an excretory organ, and mor- phologically interesting from its relations to the proboscis and its resemblance to a similarly placed organ in the larve of Annelids. The mesoderm forms at first a simple layer, but soon gives rise to a muscular and a splanchnopleuric layer, but at the anterior end of the body no celom is developed, and here the mesoderm forms the connective tissue which surrounds the different organs of the head. Before the cleavage of the mesoderm a saccular cavity is formed around the proboscis, which grows very rapidly and extends to the hinder end of the body. This is the sheath of the proboscis, and it is absolutely independent of the ccelom. Its first rudiment has the form of a thick layer of cells surrounding the rudiment of the pro- boscis; it then divides into two layers, which are only single, for the future, at the lower end. The three blood-trunks arise before the formation of the body-cavity, and a rhythmical contraction is apparent very early. In the intestine the digestive cells appear to multiply during the whole of the life of the Borlasia, and to lead to a complete disappearance of the lumen of this canal. The lateral nerves appear from comparative data to be the homologues of the ventral chain of Annelids, but em- bryological facts offer certain difficulties to this interpretation; the rudiments of the lateral nerves are always distinctly separated from the ectoderm, and seem to be direct prolongations of the cephalic plate ; the author is inclined, therefore, to believe that the lateral nerves of Nemertines are the homologues not of the ventral chain, but of the peripharyngeal commissure of Annelids; in connection with this, we would quote the late Prof. Balfour: “A circumoral nerve-ring, if longitudinally extended, might give rise to a pair of nerve-cords united in front and behind, exactly such a nervous system, in fact, as is present in many Nemertines.”* New Human Cestode—Ligula Mansoni.;—Dr. T. 8. Cobbold describes a Cestode, twelve of which were found in a Chinese, lying in the subperitoneal fascia, about the iliac fosse, and behind the kidneys, a single one being found lying free in the right pleural cavity. They were from 12 in. to 14 in. long, 1-8th in. broad and 1-64th in. thick. The Cestode comes nearer to Ligula simplicissima, frequently found in * Comp. Embryol., ii. p. 312. + Journ. Linn. Soe. (Zool.) xvii. (1883) pp. 78-83 (4 figs.). 374 SUMMARY OF CURRENT RESEARCHES RELATING TO the abdominal cavity of fresh-water fishes, than to any other species, and without asserting positively that it may not be a variety of that form, the author thinks, from the unique character of its habitat associated with certain differences of form, that it may properly be regarded as the immature representative of a totally distinct species. Echinodermata. Psolus and its Allies.*—Prof. F. Jeffrey Bell, after giving the reasons which justify the use of the name Psolus as against Cuvieria, and a list of the known species and well-established synonyms, proceeds to give some account of some of the forms of that genus of Holothurians. He finds that in Psolus fabricii the younger are more strongly imbricated than older specimens, and that the species has a circumpolar distribution, being found in the Japanese seas. A new subgenus—Hypopsolus—is formed for a specimen remarkable for having a comparatively small number of covering plates which are invested in a thick integument in which there are some calcareous deposits. Psolus (Hypopsolus) ambulator is found in the Australian seas. He finds that the Polian vesicle is not, as might have been supposed, better developed in the more heavily than in the less heavily armed species, and he concludes that, for the purposes of systematic zoology, it is most convenient to recognize three sub-genera—Psolus 8. Str. (Hupsolus) with granular plates, a median row of trivial suckers, and no basal web to the tentacles ; Lophothuria with large granulated plates, no median row, and a basal web; while Hypopsolus has a very rich supply of trivial suckers and the scales invested in a thick integument. Perivisceral Fluid of the Sea-Urchin.}—Prof. E. A. Schafer finds that if the perivisceral fluid of an Echinus, which has about the same specific gravity and chemical composition as sea-water, be drawn from the “ shell” it rapidly undergoes what appears to be a sort of coagula- tion ; this coagulation now shrinks until it is reduced to a small shred of coloured substance, and in this respect it closely resembles that of vertebrate blood. Examined with the Microscope, the clot is found to contain all the corpuscles, and these are so closely arranged and their processes are frequently so long and ramified, that it is difficult to make out the material in which they are imbedded. This material has been overlooked by Geddes, but by experiment it is possible to see that there is a clear substance in which the corpuscles are im- bedded ; this coagulable material does not appear to be fibrine, but to be a body more nearly allied to mucin, “although the possession by it of the remarkable property of spontaneously shrinking after its first formation gives it a deceptive similarity to fibrine.’” ‘The author promises a more detailed account of his investigation. * Proc. Zool. Soc., 1882, pp. 641-50 (1 pl.). + Proc. Roy. Soe., xxxiv. (1883) pp. 370-1. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 370 Eudiocrinus.*—Professor E. Perrier signalizes the presence of Mr. Herbert Carpenter’s new genus Hudiocrinus (so called from its known four species having been found in the Pacific Ocean) in the Atlantic ; and he proposes to call the new form (discovered by the ‘ Travailleur’) #. atlanticus. The five arms, which alone are possessed by this genus, are here greatly elongated, and only diminish slowly in diameter. It is distinguished by the number and size of the saccular organs ; it would not seem to be able to attach itself by its cirri, as do most of its allies, but to lie with arms and cirri extended on the slime of the ocean, where it fears neither waves nor currents. Hudiocrinus is not a primitive, but a modified Comatulid, and the author takes again the opportunity of pointing out that the simplest forms of all types appear to be capable of forming colonies by gemmation; and that the abyssal fauna is, in great part, made up of forms descended from littoral and shallow regions. The conditions of existence becoming more and more constant, or even altogether uniform, species from very different stations have, when a certain zone is passed, been able to distribute themselves largely, and so to give to the deep-sea fauna a monotony remarkable as compared with what obtains in the neigh- bourhood of the shore. Arctic and Antarctic Crinoids.t—Prof. F. Jeffrey Bell describes a specimen of Antedon from the Straits of Magellan which he is unable to distinguish as more than a variety from the very well known Arctic form A. eschrichti. After pointing out such differences as there are, he confesses his inability to believe that the Magellan variety and the northern form could ever have had an ancestor of the species A. eschrichtt. He concludes that a case of this kind forces on the mind the difference between the objective and the subjective view of what constitutes a species, or in other words, the differences between a Linnean and a genetic conception of specific relationship. He “ would not like to be thought to have failed to recognize that in the discrimination of the homogenetic and the homoplastic factors of species, we have at present no criterion other than what even a friendly critic might call our ignorance. Chorology and paleontology will have to do for species what comparison and embryology are doing for organs.” Classification of the Comatule.t—P. Herbert Carpenter here discusses and criticizes parts of Prof. Jeffrey Bell’s ‘Attempt to apply a Method of Formulation to the Species of the Comatulide.’ § After allowing the necessity of some method of formulation, he dis- cusses especially the formule given for those species which he has himself described. Confusion has arisen from preceding writers, himself included, having not sufficiently recognized the different * Comptes Rendus, xcvi. (1883) pp. 725-8. + Proc. Zool..Soc., 1882, pp. 650-2. { Ibid., pp. 731-4. § See this Journal, ii. (1882) p. 791. 376 SUMMARY OF CURRENT RESEARCHES RELATING TO morphological values of a syzygy in the proximal and in the distal portions respectively of the rays and their subdivisions. A fresh mode of formulation is given which it is hoped will be found more elastic, and is based upon seven important generalizations, which are formally stated. He indicates the presence of ten arms only by the number 10; assumes that, unless otherwise stated, the first syzygy on the arm is on the third brachial; if it is on the second, 2 6 is placed in the formula: 2d or 2 p indicates that there are two distichals or two ; d palmars, of which the axillary is a syzygy, and g oF f that the two distichals or palmars are united by a syzygy. Like Bell, he uses R to denote the syzygial union of the two outer radials, and he accepts the proposal for the cirri. Ceelenterata. Origin of the Spermatozoa in Meduse.*—In a short paper on this subject C. Merejkowsky calls attention to the interesting fact that the mature reproduction-follicle of Cassiopea or Rhizostoma bears a close resemblance to the same organ of Pelagia during its very young stages. Ata very early stage of development the immature follicles are almost exactly alike in all three genera, but in Cassiopea they undergo very little change. The mature organ is a simple ovoidal pouch, lined with endoderm-cells, and filled with spermatozoa. Accord- ing to the brothers Hertwig, Pelagia passes through a similar stage long before maturity is reached; but its development in this genus does not stop here, and it finally becomes a long, irregular pouch, the tortuous ramifications of which are interlaced in an inextricable tangle. “it is easy to discern that the simple pouches of Cassiopea open, when mature, into the genital sinus, into which Merejkowsky has seen the ripe spermatozoa escape. He believes that similar openings pro- bably exist in Pelagia ; and he thinks the failure of the Hertwigs to find them is due to the great complexity of the mature follicle in this genus, rather than to the absence of openings. The paper also contains a minute illustrated account of the transformation of the endoderm-cells which line the follicle into spermatozoa. Endodermal Nervous System in Hydroids.;—Dr. Lendenfeld states that he independently discovered in Australian species of Eudendrium and Campanularia the ring of glandular cells which has been recently described by Weissmann and Jickeli in Hudendriwm. He also finds in all the Campanularide which he has examined a well- developed nerve-ring of endodermal origin, running around the proboscis, just inside the oral opening. In this region a number of sensory cells are found, with stiff hairs, which project among the cilia * Arch. Zool. Expér. et Gén., x. (1882) pp. 577-82 (1 pl.). Cf. Science, i. (1883) pp. 287-8. + Zool. Anzeig., vi. (1883) pp. 69-71. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. Ott of the endoderm-cells. The study of sections shows that these sensory cells are connected with the ganglion-cells, and the processes which are given off from these ganglion-cells anastomose with each other in such a way as to form a complete nerve-ring around the mouth. This ring he regards as the central nervous system of Hydroids, and he calls attention to the fact that it not only originates from the endoderm, but is without a homologue in the Medusz, since none of the Medusz are known to have a nerve-ring in this position. Development of the Tentacles of Hydra.*—The great variability of fresh-water hydre demands that the order of development of the tentacles should be tabulated in a great number of specimens, in order to discover the law of their appearance. Jung has thus studied nearly 250 specimens of three species; and he concludes that, while there is no fixed order, each species does have a typical or average mode of development, which is more or less closely followed by the majority. The law varies with the species, and the results of Jung’s researches are shown in the following diagrams :— Hydra grisea. Hydra oligactis. Hydra viridis. 6 3. 1 4 3 6 3. b) 4 oe SSS — = & S| = 7 2 J 2 1. 3 2 5) 4, 6 6 3. 4 4 3. 1 4) 8. b) ee ee —. 1, —— Ie 2 1. 6 1 6. 7 5 4. 3 The vertical line is that axis of the bud which passes through the axis of the parent. The upper series of diagrams shows the typical order of appearance in normal buds of the three species named. This order was followed in 46 per cent. of 156 specimens of H. grisea, in 83 per cent. of seven specimens of H. oligactis,and in 55 per cent. of 21 specimens of H. viridis. The second line shows the order of re-appearance in specimens after cutting off the oral end of the body with the tentacles. It was followed in 69 per cent. of 48 specimens of H. grisea, in 3 specimens of H. oligactis, and in 47 per cent. of 12 specimens of H. viridis. * Morph. Jahrb., viii. (1882) pp. 339-50. Cf. Science, i. (1883) p. 81. 378 SUMMARY OF CURRENT RESEARCHES RELATING TO Porifera. Vosmaer’s Porifera.—The second part of this work on sponges, with plates V. and VI., has appeared; the whole of the text is devoted to the history of the investigation of this subject, and is not yet completed. Plate V. is filled with figures borrowed from Zittel, and some of that paleontologist’s figures, with others from Haeckel, and two new ones are to be found on plate VI. Fresh-water Sponges of Russia.*—The 12 nominal European species of the Spongillide are considered by Dr. W. Dybowski to be reducible, by exclusion of synonyms, to five, viz. S. lacustris auctt., fluviatilis auctt., vespa Martens, erinaceus Lieberkihn, muelleri Lieberkiihn. Of these species S. lacustris is the only one recognized by Dr. Dybowski from the Russian Empire; it appears to extend to near Lake Baikal and to Kamtschatka, although some hook-like appendages upon gemmules of specimens from the latter country throw some doubt on their identity. Besides this is described a new species, Spongilla sibirica, from Lake Pachabicha (near Lake Baikal) and a lake in the Caucasus, distinguished from other species by the proportions of the spicules and structure of its gemmule ; also three species of Meyenia, to which, in consideration of his want of informa- tion as to the characters of previously described species, the author with praiseworthy prudence refrains from assigning specific names ; of these Meyenie, No. 1, from Livonia and Southern Russia, is dis- tinguished by the often, and deeply, cleft margin of the amphidisk- spicules; No. 2, from Esthonia, Poland, and the Dnieper, has similar amphidisks, but has the skeleton-spicules shorter; in No. 3, from Kamtschatka and Minsk, in Western Russia, the ends of the amphi- disks are deeply cleft into a few large teeth and some or all of the skeleton-spicules are spined; the specimens from the two localities differ in small points from each other. In the last species Dr. Dybowski finds the same phenomenon as Mr. J. G. Waller (in 1878) did in S. fluviatilis, viz. the occurrence of both spined and smooth skeleton spicules in the same specimen. As in the genus Lubomirskia in 1880,} so in Spongilla and Meyenia now, the author finds a considerable range of variation in the sizes of the spicules, e.g. the skeleton-spicules of S. lacustris may range from -114 mm. to -25 mm. in length, and from -002 to ‘01 mm. in thickness in different specimens, those from salt water (Gulf of Finland) all bearing smaller spicules than the other specimens; the gemmule-spicules of fresh-water examples range from ‘024 to -05 mm. in length, and from -02 to 04 mm. in thickness. Of Spongilla sibirica, the only specimens of which spicule-measurements are given exhibit a comparatively low range of variation, but here, as in the other species described, the range of variation appears to be intimately connected with the number of localities from which specimens were examined, and in none of the species does the variation of the skeleton- * Mem. Acad. Sci. §t. Petersburg, xxx. (1882) No. 10, 23 pp. (3 pls.). + See this Journal, i. (1881) pp. 257-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 379 spicules reach so high a pitch as in S. lacustris, although in Meyenia No. 2, the length of the amphidisks and the diameter of their end- disks both vary from -006 to -014 mm. The diameter of the gem- mules of S. lacustris ranged in the Russian specimens from ‘28 to ‘4mm. The gemmule of S. sibirica is remarkable for its two layers, the inner firm, structureless, yellow, the outer thin, colourless, trans- parent, and made up of non-nucleate, polygonal cells. A useful list of 84 papers dealing with this group is appended. Protozoa. Butschli’s Protozoa—Parts 17-19, with plates XXIX. to XXXVIII. of this work have appeared. The text deals with the Sporozoa. The Gregarinida are divided into the two orders of the Monocystidea and of the Polycistidea, each with 13 genera. The three genera of the latter order lately described by Schneider are subsequently noticed. The wide distribution among the Invertebrata of these parasites is noted, and their common occurrence among mammals is pointed out. The next chapter deals with the Myxo- sporidia or so-called fish-psorosperms, and the spore-formation is carefully described. The lately suggested name of Sarcosporideia (Balbiani) is applied to the “tubes” (sarcocysts) of Miescher and Rainey, the correct relations of which to the Gregarinida must still remain an open question. The figures illustrating the Radiolaria are completed, and those of the Sporozoa commenced. Flagellate Infusorian, an Ectoparasite of Fishes.*—L. F. Henneguy describes an ectoparasite of young trout, which seems to cover their surface. When fixed these infusoriform parasites have the appearance of small pyriform cells, fixed by their narrower end. A clear line divides the body into longitudinal asymmetrical halves, and this line corresponds to a groove in which is placed a long flagellum. When the animal is free it expands and has the form of a Haliotis- shell. If the fish dies the infusorian guest abandons it and disappears, probably to take up its abode on another. In ordinary infusions the parasite cannot live, for fresh water appears to be a necessity of its existence. Most nearly allied to Bodo (Amphimonas) caudatus, it is dis- tinguished by having three, instead of two, flagella; the new form may be called B. necator. This, which appears to be the first de- scribed ectoparasitic flagellate infusorian, seems to cause the death of its host by giving rise to an alteration in the activity of the cells of the epithelium; for in a young trout the cells appear to be under- going active division, which ceases when it becomes attacked by this parasite. Gigantic Actinospherium Eichhorniit—Professor J. Leidy noticed in an aquarium what appeared to be eggs adherent to the - edges of the leaves of Vallisneria. On examining the egg-like bodies * Comptes Rendus, xevi. (1883) pp. 658-60. + Proc. Acad. Nat. Sci. Philad., 1882, p. 260. 380 SUMMARY OF CURRENT RESEARCHES RELATING TO with a lens, they were observed to be covered with delicate rays. On transferring some of the bodies to the field of the Microscope, they proved to be giant specimens of the larger sun-animalcule, Actino- spherium Hichhornii. They measured from three-fourths to one milli- metre in diameter, independent of the rays, which extended from one- fourth to half a millimetre more. One of the smaller individuals contained four water-fleas (Daphnia), a third of a millimetre long ; and one of the larger contained six of these. The Actinospherium appears to be tenacious of life, several specimens having been retained alive and in good condition for three days in a drop of water in an animalcule cage. They had discharged the Daphnia, but retained their original size. One of oval form measured 1 mm. long by 0:75 mm. broad. The smaller ones measured 0°75 mm. in diameter. After another day they appeared in good condition; but the rays were contracted so as to be about half the original length, and many had a minute granular ball at the end, apparently effete matter thrown off from them. At this time the animalcules were returned to the aquarium. Dimorphism of Foraminifera.* —MM. Meunier-Chalmas and Schlumberger, attracted by the discovery by one of them of the pre- sence of two forms in every species of Nummulite, have lately directed their attention to the Miliolide, where they have observed similar phenomena; so that dimorphism is to be detected in both the great divisions of the Foraminifera-Perforata and Imperforata. The di- morphism of the Foraminifera is characterized by a difference in the size and arrangement of the primary chambers; the smallest and those of a median size have a central chamber, which is relatively very large (orm A), while in larger forms this cavity is only visible when highly magnified (Form B). In a given species no external character, save that of size, would give the least suspicion of this difference. The authors proceed to give some details of the distinctive cha- racters of the two forms, and promise in a further communication to discuss the hypotheses by which this remarkable difference may be explained. Vampyrella Helioproteus, a New Moneron.{—T. W. Engelmann describes this new organism, which he found among Conferve in the neighbourhood of Utrecht. It is distinguished from all previously known forms by the “heliozoa-form” (globular, with long pseudo- podia), being able to pass over into the round flat discoid amceba- form. ‘This metamorphosis was observed in three instances, and extended over about five minutes. In the heliozoa-form the organism moves by means of its long contractile pseudopodia, like an Actino- spheerium ; in the amceba-form it creeps without pseudopodia or change of form. It bears a very close resemblance to Hyalodiscus rubicundus (Hertw. and Less.), differing only in the absence of a nucleus and of * Comptes Rendus, xevi. (1883) pp. 862-6. + K. Akad. van Wetensch. Amsterdam, Nov. 25, 1882. See Bot. Centralbl., xiil. (1883) p. 214. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 381 contractile vacuoles. The author adduces, from the discovery of this organism, a fresh argument against drawing any sharp line between the different sections of the Protista. Heematozoa of Fishes.*—P. Mitrophanow gives some account of new monadiform parasites in the blood of fishes, and discusses their relations to the blood-corpuscles. He points out that, in consequence of their having been looked upon as “curiosities,” the literature that deals with the presence of foreign organisms in the blood of healthy animals is in a very fragmentary condition. The author has dis- covered in the blood of Cobitis fossilis and of Carassius vulgaris an organism which, at first sight, appeared to be a Nematode, but which exhibited, on closer examination, no internal differentiation, and some amoeboid characters. Of about 30-40 » long, it was only 1-1} p broad, and moved with great rapidity ; at its anterior end there was a flagellum of considerable length, and the anterior was narrower than the hinder end. When dying, or less active, the organism became much shorter, and an undulating membrane became apparent. The body of the organism, the membrane, and the flagellum, all ex- hibited a homogeneous highly refractive protoplasm of great contrac- tile power. Some striking varieties of this form are described. The hematozoon found in Carassius vulgaris was at first sight similar to that found in C. fossilis, and just described, but it differed from it in its somewhat larger size, and in the more distinct appearance of its undulating membrane. For the reception of these forms a new genus must be established which may be known as Hematomonas, and the two species as H. cobitis and H. carassii. After giving an exact definition of these forms, the author proceeds to refer to the views of Gaule, and states that he comes to the conclusion that he has here to do with organisms, and not with the derivates of anatomical elements, and he agrees with Prof. Ray Lankester that we have here Cytozoa. In consequence of the paper of the last-mentioned naturalist,t he feels it would be superfiuous to discuss in detail his objections to Gaule’s views. BOTANY. A. GENERAL, including Embryology and Histology of the Phanerogaimia. Nature of the Process of Fertilization.t—EH. Strasburger gives a résumé of the various modes in which the sexual elements, whether “ planogametes”” or “aplanogametes,” unite in various classes of alge. He repeats his previously expressed view that impregnation consists essentially in the union of the morphologically equivalent parts of the two cells that unite. This union is, however, confined to the cell-protoplasm and cell-nucleus, and does not extend to the chro- * Biol. Centralbl., iii. (1883) pp. 35-44. + See this Journal, ii. (1882) p. 519. { Niederrhein. Ges. f. Natur- u. Heilkunde, Bonn, Dec. 4, 1882. 3882 SUMMARY OF CURRENT RESEARCHES RELATING TO matophore. The fact that the reduction in size of the spermatozoid is accompanied by a loss of protoplasm, and that the nuclear substance predominates in the mass of the spermatozoid, has led to the conclusion that what takes place in impregnation is chiefly a transport of nuclear substance, while the cell-protoplasm in the zygote or impreg- nated oosphere plays the part of a storage of force. Impregnation is therefore essentially a union of cell-nuclei, although any union of cell-nuclei is not necessarily an act of impregnation. The coalescence of the plasmodia of Myxomycetes he does not regard as an act of impregnation. The ordinary mode for the protoplasm of the male element to reach that of the female element is by permeation through pores already in existence, though in certain instances it would seem as if it made use of pores specially prepared for the occasion, Pollination of Aracex.*—G. Arcangeli has observed the mode of pollination of several species of Aracez, especially Arum italicum, Dracunculus crinitus, vulgaris and canariensis, and Sauwromatium gutta- tum. In all of these a very great rise of temperature is observable within the spathe for a very short time at the moment of flowering, accompanied by a powerful odour. The object of these is to attract insects to assist in the fertilization. These are detained by the parastemona as in a cage from the time when the stigmas are mature until the dehiscence of the anthers; A. italicum at least being distinctly proterogynous. The author does not consider there is sufficient evidence to warrant the theory of the carnivorous habits of these plants, there being a complete absence of any digestive fluid and of any special digestive glands in the spathe. Pollen-tubes.t—J. Kruttschnitt disputes the ordinary view that the ovule is fertilized by the entrance of the pollen-tube into the embryo-sac. He has never been able to detect that such an entry actually takes place. He believes, on the contrary, that the pollen- tube discharges the fovilla or contents of the pollen-grain into the conducting tissue of the style, whence it is conducted by the funicle to the papillz which surround the micropyle, and then absorbed by endosmose. In the case of Cereus grandiflorus he states that the ovary contains on an average about 38000 ovules, and that it is impossible, on the ordinary theory, that all these ovules could become fertilized, for there is not nearly space, either in the conducting tissue of the style or in the ovarian cavity, for this number of pollen- tubes. Autoxidation in Living Vegetable Cells.t—Traube has given the name of autoxydable Koérper or, as we must clumsily translate the new term, autoxidizable substances, to those bodies which, at a low temperature, and by the action of free passive oxygen, can be oxidized, forming, in the presence of water, peroxide of hydrogen. Starting * Nuoy. Giorn. Bot. Ital., xv. (1883) pp. 72-97. + Amer. Mon. Micr. Journ., iii. (1882). } Bot. Ztg., xli. (1883) pp. 65-76, 89-103. Cf. Science, i. (1883) pp. 229-30. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 383 from Traube’s statement of the changes which accompany oxidation, especially the formation of peroxide of hydrogen, J. Reinke gives the following as a sufficient basis on which to build a theory of oxidation in living cells. (He has himself shown that there exists in certain plants, notably in the beet, a very easily oxidizable body, which he has named rhodogen. This substance is one of Traube’s autoxidizable bodies, and is only one of many which may be reason- ably assumed to be present in cells.) 1. In every active cell, autoxidators are formed; that is, sub- stances which, at a low temperature and with absorption of molecular oxygen, can be oxidized by the decomposition of water. 2. By oxidation of these substances, peroxide of hydrogen is produced. 3. This peroxide of hydrogen can, under the influence of diastase, and probably of other ferments, cause oxidations as energetic as atomic oxygen can. Lastly, the seat of this activity is the periphery of the proto- plasmic body of the cell; and this body possesses an alkaline reaction. Structure of the Bundle-sheath.*—The cells of the typical bundle-sheath are, according to 8. Schwendener, parenchymatous and of variable length; the pores, when present, are mostly round, though occasionally oval and oblique. Like the mestome-bundles, the sheaths form a continuous system. The impermeability of the walls of the sheaths is no invariable characteristic, since portions only of them are often cuticularized. It is, however, the rule for the bundle-sheaths to be, when mature, less permeable than ordinary cellular tissue, this being due to a relatively impermeable lamella, which bounds the inner surface of their tangential walls; in consequence of this the sheaths often assume the functions of the epidermis. The formation of pores on the inside of the sheaths stands in close relationship to the mode in which their permeability decreases in the course of their development. When the inner wall has become so thick as to be impermeable there are no pores. In many monocotyledons, dicotyledons, and ferns, the cells of the bundle-sheath of the root are of two kinds; opposite the primordial vessels are “ transmission-spots” more permeable than the rest of the sheath, from the cells having thinner walls. The vessels are water- conducting tubes, and these transmission-spots serve to keep up a connection between this system and the fresh bark; they are the sluices of a system of irrigation. In the mestome-sheath of mono- cotyledons these passages are found at two symmetrical points, while in ferns they always correspond, in number and position, to the groups of primordial bundles. These passages appear never to occur in the bundle-sheaths of rhizomes. Besides the suberization of the radial and transverse walls of the bundle-sheaths, the tangential walls remaining unchanged, Schwen- * Abhandl. K. Akad. Wiss. Berlin, 1882 (5 pls.). See Bot. Centralbl., xiii. (1883) p. 77. 384 SUMMARY OF CURRENT RESEARCHES RELATING TO dener distinguishes several modes of mechanical thickening, viz. of the cell-walls of the sheath itself; of the walls of the neighbouring cortical cells, as is usually the case in ferns; of both these; of the cells of the sheath, and of the layers of cells which bound it on the inside, &e. The bundle-sheaths are formed, in the most various ways, from a true cambium as well as from a meristem ; and the thickenings are also either of parenchymatous or of cambial origin. Buried Leaf-buds.*—F. Hildebrand describes several cases of adventitious leaf-buds which have become completely covered over by the surrounding tissue, and concealed by the bark, breaking out, how- ever and developing in the following season. They occur in Actinidia polygama, Rhus glabra, Ptelea trifoliata, Virgilia lutea, Calycanthus floridus, and Philadelphus inodorus. Structure of the Wood of Conifers.t—E. Russow publishes a very detailed account of the structure of the wood, especially of Picea excelsa and Larix sibirica, with especial reference to the development of the pits and of the membrane of the wood-cells. The general conclusions arrived at are as follows :— The vessels and tracheides act as pumps, which, either by suction or pressure, force the water in the wood from the root to the leaves. The suction is first caused by transpiration, by means of the bilateral pits in the wood; the positive pressure by the osmotic force of the contents of the paratracheal cells of the medullary rays, and paren- chyma of the wood by means of the unilateral pits. The latter manifests itself especially at the time when negative pressure prevails in the vessels or tracheides, in order to bring about filtration of diffi- cultly diffusible substances in the cells of the medullary rays and of the wood-parenchyma. Medullary Rays of Conifers and Dicotyledons.j—P. Schulz describes the pores in 48 species of conifers occurring in the con- tiguous walls of the tracheides and in the cells of the medullary rays, by which these elements communicate with one another. Those in the medullary rays are always unbordered, while those in the tracheides are sometimes bordered, sometimes not. In some species of Pinus the tracheides which border the medullary rays have I-shaped thickenings, the medullary rays having at the same time large oval pores. They protect the tracheides from the pressure exercised by the turgidity of the medullary cells. The medullary tracheides occur only in the Abietinez, and are of two forms. In Pinus these cells are thickened in a jagged way, and are arranged in several rows; in Cedrus, Larix, and many species of Abies, they are narrowed, have not these jagged thickenings, and are usually arranged in one or two rows in each medullary ray. The bordered-pit-cells are dead and * Bot. Centralbl., xiii. (1883) pp. 207-12. + Ibid., pp. 29-40, 60-8, 95-109, 166-73 (5 pls.). ¢ Schulz, P., ‘Das Markstrahlengewebe u. seine Beziehung zu den leitenden Elementen des Holzes,’ 23 pp. (1 pl.) Berlin, 1882. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 385 have no power of turgidity, performing the function of receptacles for water. In dicotyledons the medullary rays are also connected with the vessels by pores, which sometimes attain a very great size. The woody parenchyma and medullary rays stand in a close relationship with the vessels, and together furnish a channel for the transport of solutions of organic compounds; the sap is conducted through the former, while the vessels serve as reservoirs to which the former give up their superfluous sap, and take it up again from them when wanted. Diagnostic Value of the Number and Height of the Medullary Rays in Conifers.*—B. Essner points out that these characters cannot be used for the determination of the species of fossil coniferous woods, as has been proposed, since both the number and height of the medullary rays are subject to considerable variation in the same species according to age; they are most numerous in the first annual ring, then decrease, and subsequently again increase. Their height increases regularly with their age. Achenial Hairs and Fibres of Composite.t—G. Macloskie describes the peculiar hairs attached to the achenes of many Com- posite. Duplex hairs are characteristic of the families Asteroidee, EKupatoriex, Vernoniex, Helianthoidex, Helenioidese, Arctotidex, and Mutisiex ; but do not occur in Anthemidee or Cichoriesx. Each hair consists of two tubes with a partition between, like the two flues of a double chimney ; they contain special fibres or elaters which are rapidly uncovered on access of moisture, swelling and escaping by the tips of the tubes, as by the lifting of a pair of trap-doors. There are also similar fibres contained in superficial cells of the pericarp in Cichorieze, which aid in the dehiscence of the seed-vessel (generally described as indehiscent), and the pressing out of the seed. Crystals of Calcium oxalate in the Cell-wall.t—Crystals of calcium oxalate in the cell-wall have hitherto been observed in Mesembryanthemum, Sempervivum, Dracena, Araucaria, Welwitschia, and Ephedra. WH. Molisch records an additional instance in Nuphar and Nymphea. 'They occur especially in the walls of the well-known stellate hairs of the fundamental parenchyma which surrounds the intercellular spaces of the leaf and leaf-stalk. The crystals vary greatly in size from all but invisible points to 6-6 » in length. Influence of Sunny and Shaded Localities on the Development of Leaves.$§— Haberlandt, in an examination of the comparative anatomy of the assimilating tissues in plants, came to the con- clusion that light is almost without influence in governing the shape of leaves or the arrangement of the chlorophyll-cells. On the other * Abhandl. Naturf. Ges. Halle, xvi. (1882). See Bot. Centralbl , xii. (1882) p. 407. + Amer. Natural., xvii. (1883) pp. 31-6. t Oesterr. Bot, Zeitschr., xxxii. (1882) pp. 382-5. § Jen. Zeitschr. f. Naturwiss., ix.(1882) pp. 162-200 (1 pl.). See Amer. Journ. Sci., xxv. (1883) pp. 313-4. Cf. this Journal, ii. (1882) pp. 368, 373; ante p. 92. Ser, 2.—Vok. III. pal © 386 SUMMARY OF CURRENT RESEARCHES RELATING TO hand, Pick has shown that the shape and arrangement of assimilating tissues are certainly controlled to some extent by the presence of full sunlight or of shade. Both of the foregoing works were preceded by a paper by E. Stahl in which the influence of the intensity of ight on the structure and arrangement of chlorophyll-parenchyma was pointed out. It may be further stated that the same author had previously studied the effect of the direction and intensity of light on some movements in plants. In a paper just published E. Stahl incorporates some of the earlier results obtained by him, and adds several facts of considerable interest. The thesis may be stated as follows: The elongated or palisade cells are best adapted for hght of high inten- sity; the looser parenchyma for that of low intensity. (To this in passing may be added Areschoug’s observation that the looser or spongy parenchyma is that best adapted for transpiration, and characterizes the foliage of moist climates; where either local or climatic relations render too rapid transpiration undesirable, these layers are protected by a palisade system.) 'The author has devoted most attention to plants which can endure shade as well as bright sunlight, and here wide differences are alleged to exist between the forms growing in light and those found in shade. All the differences are of the character above described, namely adaptation to sunlight by the development of a better palisade system. The critical point of the investigation is plainly that leaves developing in sunlight have a less strongly characterized spongy parenchyma, and a better marked palisade system. In view of the fact that these two systems are generally found as stated in the thesis, the author asks whether this ought not to influence our treatment with plants in greenhouses, Position of Leaves in respect to Light.*—E. Mer states that certain parts of the leaf, usually the limb, receive luminous impres- sions, while other parts, as the petiole, the motile organs, &c., execute movements for the purpose of placing the former in a favourable position for receiving light. The mechanism of these movements consists in an augmentation of growth, or only of turgidity, resulting in curvatures and torsions. The presence of light seems indispensable to these movements. Photepinasty of Leaves.|—W. Detmer proposes the term “ phote- pinasty ” for the epinastic position of leaves induced by light. The normal unfolding of leaves is due to paratonic nutation. Light first induces stronger growth in the upper side of the leaf; and it is to this phenomenon that he proposes to apply the term. Movements of Leaves and Fruits.t—The movements of leaf- and flower-stalks in virtue of which they assume an inclined or horizontal position are attributed by H. Véchting to various causes, geotropism, heliotropism, and the weight of the flowers or fruit. In addition to * Comptes Rendus, xevi. (1883) pp. 1156-9. Sce also this Journal, ante, pp. 235, 237. + Bot. Ztg., xl. (1882) pp. 787-94. ¢ Vochting, H., ‘Die Bewegungen der Bliiten u, Friichte,’ 199 pp. (2 pls.) Bonn, 1882. See Bot. Ztg., xli. (1883) p. 13. ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 387 these external, there are also internal causes, which he classes under two heads :—“ rectipetal,” those which tend to straighten the organ in question ; and “curvipetal,’ those which tend to cause it to curve. Distribution of Water in the Heliotropic Parts of Plants.*— A. Thate derives the following conclusions from experiments on Coleus, Clematis, Phaseolus, Dahlia, Sambucus, and Silphium :— 1. In the parts of plants with positively heliotropic curvature, no difference can be detected between the amount of water in the illuminated and the shaded side. 2. It cannot, however, be positively asserted that no such difference exists. 3. Very nearly exact determinations of the amount of water in the parts of plants which curve heliotropically can be obtained by Kraus’s method. Excretion of Water from Leaves.j-—-G. Volkens describes the structure of the portion of the tip of the leaf of Calla adapted for the excretion of water. In addition to the ordinary stomata, the epidermis of the cylindrical apex of the leaf is provided with very large modified stomata, which he terms water-fissures. The internal tissue is com- posed of assimilating parenchyma surrounding the extremities of the spiral bundles, which are in close contact with a tissue composed of thin-walled cells with watery contents which the author terms “epithem.” The cells of the epithem form a spongy tissue, the large and numerous intercellular spaces of which are always filled with water. The closed ends of the spiral vessels are inserted between the cells of the epithem. ‘The excretion of water in the fluid state on the surface of the leaves is due chiefly to root-pressure. The Aroides is the only order of monocotyledons that possess a true secretory apparatus. In other orders the epidermis gives way at the apex of the leaf, and the vessels discharge their superfluous water into the fissure. Where a special excreting organ is present, it usually occupies the apex and teeth of the leaf; but sometimes, as in Crassula and Urtica, is dispersed over the surface of the leaf. Movements of Water in Plants.t—-J. Vesque has devised a simple method of demonstrating the transfer of water in the stems of plants, which promises to have a wide application. The stem is cut obliquely during immersion in water, and the thin part of the severed stem is placed in the field of the Microscope, of course completely wet on the cut surface. After the cover-glass is adjusted and the stem securely fastened, so that it cannot be easily disturbed by subsequent treatment, a very little freshly precipitated calcium oxalate, or other finely divided substance, is introduced under the cover. If the leaves have not been removed from the stem, a rapid current is at once observed _* Pringsheim’s Jahrb. f. Wiss. Bot., xiii. (1882) pp. 718-29. + Volkens, G., ‘ Ueber Wasserausscheidung in liquider Form an den Blattern hoherer Pflanzen,’ 46 pp. (3 pls.) Berlin, 1882. See Bot. Centralbl. xii. (1882) . 893. : g t Ann. Sci. Nat. (Bot.) xv. (1882) pp. 5-15. See G. L. G. in Amer. Journ. of Sci., xxv. (1883) pp. 237-8. : 2.62 388 SUMMARY OF CURRENT RESEARCHES RELATING TO to flow towards the cut surface. The insoluble salt collects at the open mouths of the vessels, often passing into the capillary tubes after a temporary arrest, and the same phenomenon is repeated several times as the minute plugs are formed and then sucked in. With low powers of the Microscope it is possible to use a second slip instead of the thin cover, and then the simple apparatus can be held more firmly in its place. In any case it is possible to measure the rapidity of the current by means of a micrometric eye-piece ; and several such measurements are given. When the stem is quickly stripped of its leaves, the current is stopped at once. But when, on the other hand, a leaf or a part of the stem is pinched, there is immediately a backward flow of water. It is well known that two conflicting views have been held by physiologists as to the channel by which the upward movement of water in wood takes place. Some think that the transfer is solely by imbibition, and that no free water is carried from cavity to cavity of the wood-element, or rather, that no free water exists in the cavities. Others have held that free water is carried from one wood-elemeut to another, and that the walls themselves play only a subordinate role. To these opposed views may be added a third, which appears to be a compromise ; namely, that water in a free state actually exists as a thin lining on the cell-wall. The chief advocate of the latter view has, however, abandoned it in favour of the imbibition theory. A recent publication by Elfving* details the results of experiments which considerably strengthen the “cavity” theory. Now just at this point come observations of Vesque, in a continuation of the paper regarding the method of direct demonstration, which go far towards showing that here, as was long ago suspected, the truth is to be found between the extremes. These experiments,“ which need to be care- fully repeated, indicate that under certain circumstances the transfer of water takes place by means of the cavities themselves, but that in all cases they may serve the part of reservoirs. Moreover, the calibre and length of the vessels regulate the rate of transpiration ; resistance to the movement of the water following the law of Poiseuille, so that the resistance is inversely proportional to the fourth power of the diameter, and directly proportional to their length. We give in full the close of Vesque’s paper. “Tt is evident that p having reached its maximum, that is to say the suction resulting from transpiration not being able to increase without changing our conditions, because the air dissolved in the water becomes disengaged, the quantity of water which arrives at the organs of transpiration across a vessel filled with water is expressed 4 by Ta From this we can see why climbing plants have such large vessels; in fact, the increase in diameter can alone compensate that of the length. And, further, the quantity of water which can pass through a vessel in a given time bears a certain relation, varying for each species, with the water which it contains. This, which I have * See infra, p. 389. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 389 called the transpiratory reserve, it might be better to term the vas- cular transpiratory reserve. I propose to publish a work on water reservoirs in general. A study of this apparatus very often gives the key as to the resistance of certain plants to certain surroundings, and permits us to indicate at once the conditions under which we must cultivate plants. Anatomy, I am convinced, will open the way to rational culture.” Permeability of Wood to Water.*—Examination of the structure of the wood in a number of gymnospermous and angiospermous trees and shrubs has led F. Elfving to the conclusion that the wood loses its permeability for water as soon as the cell-cavities become completely closed. The water of transpiration cannot therefore be conducted through the cell-walls, but filters from cell to cell. In the tracheides of the Conifers it is clear that the largest part of the cell-wall serves as a support for the separate tracheides; while the filtration can take place only at definite spots, viz. the bordered pits. Trichomatic Origin and Formation of some Cystoliths.}— _ J. Chareyre saw in a very young leaf of Morus alba that the hairs, which were very long and a little swollen at their base, were gradually filled with a striated mass incrusted by calcareous matter. With age these hairs become absorbed, their extremity undergoing atrophy, and their lower portion swelling and becoming globular. The cystolithic mass became detached from their walls, and, in the adult leaves, the extremity of the hair disappearing entirely, the basal portion, now inclosed in epidermis, formed a true cystolithic cell. We here, then, have cystoliths which are of epidermal origin and are most frequently developed at the expense of a hair, though in rarer cases from the outer wall of an epidermal cell. There is another category, examples of which are to be found in some Acanthacee and Procridex, in which the cystoliths exist in all the tissues,and are developed at the expense of the cell which contains them. The two categories may perhaps be connected together by the linear cystoliths of some Ortiz. Formation of Starch out of Sugar.j—J. Boehm contests the ordinary view that the starch formed in chlorophyll-grains is a direct result of the decomposition of carbon dioxide; he believes it to be in many cases formed out of other organic substances, especially sugar, which have found their way into the chlorophyll-grains. Starch is in this way often formed in the absence of light in grains of chlorophyll or of etiolin. In order to confirm this hypothesis, leaves and pieces of the stem of the scarlet-runner, containing no starch, were exposed to the action of a solution of sugar, when they were found, after twenty- four hours, to contain abundance of starch; the quantity depending on the concentration of the solution of sugar; the temperature, between the limits of 10° and 20° C., appearing to make no difference. In leaves of Galanthus, Hyacinthus, Iris, &c., starch was produced in * Bot. Zte., xl. (1882) pp. 707-23. + Comptes Rendus, xcvi. (1883) pp. 1073-5. t Bot. Ztg., xli. (1883) pp. 33-8, 49-54. 390 SUMMARY OF CURRENT RESEARCHES RELATING TO the same way in from eight to ten days, as well as in many other cases. The author believes, therefore, that the first demonstrable product of the decomposition of carbon dioxide is not starch, but sugar, and in all probability this is really the first product formed. Distribution of Energy in the Chlorophyll-spectrum.*—C. Timi- riazeff points out the intimate relationship between the absorption of light by chlorophyll and the intensity of the chemical phenomena produced, the curves of absorption of light and of the decomposition of carbon dioxide presenting an almost exact concurrence. This last function may be considered as dependent on the energy of radia- tion as measured by its effect on the thermopile. Langley has definitely fixed the position of maximum energy in the solar spectrum to be in the orange, exactly in that part which corresponds to the characteristic band of chlorophyll, between B and C. It results, therefore, that chlorophyll may be regarded as an absorbent specially adapted for the absorption of those solar rays which have the greatest energy; and its elaboration by the vegetable economy is one of the most striking examples of the adaptation of organized beings to the conditions of their environment. , Under the most favourable conditions 40 per cent. of the solar energy corresponding to the rays of light absorbed by the charac- teristic band of chlorophyll, is transformed into chemical work. Chlorophyll therefore constitutes an apparatus of great perfection, capable of transforming into useful work 40 per cent. of the solar energy absorbed. Colour and Assimilation.j—T. W. Engelmann has made an extensive use of the so-called bacteria method for investigating the effect of light on chlorophyll-cells, and he now gives further details of his experiments, with some of his conclusions. The effect of free oxygen upon quiescent bacteria is so great that by their presence the trillionth of a milligram of the gas can be detected. When a green cell in water is evolving oxygen, even to an extremely minute amount, the movements of the bacteria afford instantaneous indication of its presence. Moreover, when the ray of light, shining through or on the green cell, is unfavourable to the process of assimilation and evolution of oxygen, the effect on the bacteria is at once shown. All of Engelmann’s experiments were checked by control observations. The results are mainly as follows :— Only those cells which contain particles of coloured protoplasm evolve oxygen in the light. When colourless protoplasm was screened by a coloured solution, or was illuminated by light coming through a green leaf, no oxygen was evolved. It will be seen that this has a direct bearing upon some of Pringsheim’s views. In the case of cells of different colours, e.g. green, Sphagnum and Spirogyra; yellowish- brown, Navicula and Pinnularia; bluish-green, Oscillatoria and Nostoc; red, Callithamnion and Ceramium; distinct relations between the colour and the amount of assimilation under different rays were made out. * Comptes Rendus, xevi. (1883) pp. 375-6. t Bot. Ztg., xli. (1883) pp. 1-13, 17-29. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 391 The maximum activity for green cells was in the red between B and C (the place of the most striking of the chlorophyll absorption bands); for yellowish-brown, in the green, at D } EH; for bluish-green, in the yellow ; for red, in the green. Hence there must be a series of colours other than that of chlorophyll which possess the power of assimilation in different parts of the spectrum. The maximum activity for a given colour is found in rays complementary to that colour. The author gives also an account of the possible bearing of the above on the distribution of organisms at different depths of water. Occurrence of Allantoin and Asparagin in Young Leaves.* —E. Schulze and J. Barbieri removed branches of the birch, plane, and horse-chestnut provided with buds, and placed them in water at the ordinary summer temperature until growth had ceased in the buds. In the extract from the buds, asparagin could be detected in all three cases. In that from the chestnut there was also an amide with the reaction of leucin, and in that from the plane a substance identical in composition and properties with allantoin, C,H,N,O,. Cholesterin, Phytosterin, Paracholesterin, &c.t—E. Schulze and J. Barbieri found a considerable quantity of cholesterin in etiolated seedlings of Lupinus luteus, the substance obtained from the seeds and cotyledons exhibiting to a great degree its ordinary properties. On the other hand that obtained from the root and tigellum showed essential differences, especially in a considerably higher fusing-point. The authors propose for it the term “ caulosterin,” and regard it as a distinct member of the group, with the probable formula C,,H,,O. The group will then consist of five members, with the following fusing-points :—cholesterin 145°-146°, phytosterin 132°-133°, para- cholesterin 134°-134-5°, caulosterin 158°-159°, and isocholesterin 138°-188 : 5°, Respiration of Submerged Parts of Plants.[—A. Barthélemy records observations on Nymphea and Nelumbium, which confirm his previously published view that the disengagement of bubbles of gas is not a normal property of submerged leaves, but is the result of accidental circumstances, and that, in consequence, the special respira- tion of green leaves has not the importance to the plant which is usually attributed to it. Freezing of Liquids in Living Vegetable Tissue.§—T. Meehan, referring to the prevalent opinion that the liquid in vegetable tissues congeals as ordinary liquids do, and expanding, often causes trees to burst with an explosive sound, states that experiments on young and vigorous trees, varying from one foot to three feet in diameter, demonstrated that in no instance was there the slightest tendency to expansion, while, in the case of a large maple (Acer * Journ. prakt. Chem., xxv. (1882) pp. 145-58, See Bot. Centralbl., xiii. (1883) p. 263. _t Journ. prakt. Chem., xxv. (1882) pp. 159-80. See Bot. Centralbl., xiii. (1883) p. 264. Cf. Liebig’s Ann. Chem., cexi. (1882) pp. 283-4, { Comptes Rendus, xcvi. (1883) pp. 788-90. § Proc. Acad. Nat. Sci. Philad., 1883. 392 SUMMARY OF CURRENT RESEARCHES RELATING TO dasycarpum), 3 ft. 113 in. in circumference, there appeared to be a contraction of 1-8th in. In dead wood soaked in water there was an evident expansion, and the cleavage with explosion, noted in the case of forest-trees in high northern regions, may result from the freezing of liquid in the centre of less vital parts of the trunks. In some hardy succulents, however, instead of expansion under frost, there was a marked contraction. The joints or sections of stem in Opuntia Rafinesquei and allied species shrink remarkably with the lowering of the temperature, so that the whole surface in winter is very much wrinkled. Assuming as a fact that the liquids in plants which are known to endure frost without injury do not congeal, it might be a question as to what power supplied the successful resistance. It was probably a vital power, for the sap of plants, after it was drawn from them, congealed easily. In the large maple tree already referred to, the juices not solidified in the tree exude from the wounded portion and then freeze, hanging from the trees as icicles, often 6 in. long. Influence of Electricity on Vegetation.*—M. Macagno has experimented near Palermo upon the influence of atmospheric elec- tricity on the growth of grape vines. Sixteen feet were submitted to the action of an electric current, by means of a copper wire inserted by a platinum point in the extremity of a fruit-bearing branch, while another wire connected the branch at its origin with the soil. The experiment lasted from April to September. The wood of the branches which were experimented upon contained less potash and other mineral matters than the rest of the vine, but the leaves had an excess of potash under the form of bitartrate; the grapes collected from the electrized branches furnished more must, contained more glucose, and were less acid. B. CRYPTOGAMIA. Cryptogamia Vascularia. Male Prothallium of Equisetum.t—D. H. Campbell describes the development from the spore of the male prothallium of Hquisetum arvense. When the spores are sown under glass or on damp earth, they germinate almost immediately. They first put out a nearly colourless rhizoid, the body of the spore then dividing into two cells by a longitudinal septum. Directly after germination, the chlorophyll begins to collect into distinct chlorophyll-bodies ; the mode of sub- sequent cell-division varies considerably; some of the prothallia showing a tendency to branch quite early. Some of the prothallia send out a second rhizoid from one of the lower cells; finally they become somewhat club-shaped. The first mature antherozoids were observed nearly six weeks after the sowing of the spores. The structure of the antheridium is extremely simple, consisting simply of a cavity or excavation in the end of a branch of the pro- thallium. It commences by a concentration of protoplasm at the spot, * ‘Tes Mondes.’ See Journ. Frankl. Institute, exy. (1883) p. 311. + Amer. Natural., xvii. (1883) pp. 10-15 (2 pls.), ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 393 the cavity being gradually formed, at first indistinct, but finally assuming a nearly regular oval shape. The protoplasm soon breaks up into small round bodies which are discharged as antherozoids. The first antheridia are formed singly; but later two or three are formed almost simultaneously at the end of a single branch. When the antherozoids are mature, the cells surrounding the interior cavity of the antheridium separate, leaving an opening by which they escape. Usually the whole mass of antherozoids is discharged in a few minutes, but sometimes the discharge is more gradual. Each antherozoid is inclosed in, and les coiled up within, a membrane. After resting for a few moments this sac bursts, freeing the inclosed antherozoid, which immediately swims rapidly away, with a peculiar undulatory move- ment due to its spiral form. ‘The antherozoids are of comparatively very large size. ‘The body is long and slender, tapering to a point at one end, and bearing the remains of the enveloping sac on the inner side. They are quickly killed by iodine ; the cilia becoming rigid, and standing out in all directions from the thicker end of the antherozoid. Reproductive Organs of Pilularia.*—K. Goebel has examined the development and structure of the fructification of Pilularia globulifera. A longitudinal section of the young fructification shows that the chambers in which the sporangia are formed are not closed, but have an opening at the apex. The chambers are therefore not of endo- genous origin, but are merely depressions in the surface. A placenta springs from the outer wall of each chamber in the form of a cushion ascending from below upwards, on which the sporangia are developed, usually in ascending succession. The placentz are therefore, as in Marattiacez, also products of superficial cells. The four projecting ridges which correspond to the four chambers do not meet in the centre of the fructification, but are separated by a moderately large mass of tissue, which, when the fructification is ripe, separates into four sections. Goebel does not agree with Juranyi in regarding these projections as tips of leaf-segments, but simply as outgrowths of the outer margin of the four pits in which the sporangia are formed. The entire fructification of Pilularia is, according to this view, a simple leaf-segment, in depressions of which the sori are developed, as in the homosporous Filicinee. The central mass of tissue which separates the pits from one another does not at first present any differentiation into four pits. This view of the structure of Pilularia is confirmed by a comparison with Marsilea. The idea that the fructification of Pilularia is composed of four leaf-segments has originated from the structure of the mature organ, which splits into four parts. But this results from the central tissue between each pair of soral chambers splitting intotwo. In the centre of the fructification is often a cavity caused by the violent rupture of the tissue; but this was always occupied originally by starch-con- taining tissue. The lines where the rupture subsequently takes place * Bot. Ztg., xl. (1882) pp. 771-8 (1 pl.). 394 SUMMARY OF CURRENT RESEARCHES RELATING TO are formed of narrow tabular amylaceous cells, and are in direct connection with the placental tissue. 'The whole of the rest of the tissue goes to the formation of the mucilage which brings about the opening of the fructification. The tissue bounded by the lines of separation, which surrounds the séparate soral chambers, is sometimes termed in Marsilea the indusium, a term which is correct physiologically, but not morpho- logically. It is in the Marsileacee formed by differentiation of definite portions of the tissue of the leaf and the splitting up of these ; and is not, as in the other Filicinex, either a development of the surface of the leaf or the recurved margin of the leaf itself. In the pedicel of the young fructification is a vascular bundle, which branches above into two arms; in the mature organ are twelve branches. The true position of the fructification has been a matter of con- troversy. When mature it appears as if placed in the axil of a leaf and independently of it. But that it is not in fact axillary is shown by the presence in addition of a true axillary shoot, and also by the structure of the vascular bundles. The examination of young stages shows clearly the foliar origin of the fructification. As in Marsilea, the sori of Pilularia spring from the upper side of the fertile portion of the leaf; as is shown by the position and structure of the pits. In all essential points the origin of the macrosporangia and micro- sporangia corresponds to that in Marsilea; and the same is the case with the origin of the sori; in this respect the author differs from Russow’s conclusions. The soral canal can be made out at the time when the placenta is being formed, and is a direct continuation of the pits. As in Marsilea the placente are formed out of superficial cells in depressions in the young fructification, corresponding to the structure in the homosporous ferns and in Salviniacee. Aerial Branches of Psilotum.*—C. E. Bertrand divides the aerial branches of adult Psilotwm into the following classes, differing in their morphological value :—(1) Aerial branches of the first order: Cladode- or branch-stocks ; (2) Aerial branches of the second or a higher order: Cladodes of the order in question; (8) Terminal branches or terminal cladodes; (4) Simple aerial branches; (5) Sporangiferous branches or sporangiferous cladodes. Underground Branches of Psilotum.{—C. E. Bertrand states that any transverse section of the median region of a simple underground branch of adult Psilotum shows the following parts :—(1) A bicentral slightly elliptical vascular bundle, the centre of which corresponds to the centre of the section. (2) A protecting sheath surrounding the bundle. (3) Between this sheath and the superficial layer a thick zone of primary fundamental tissue, not differentiated into distinct layers. (4) A superficial layer of epidermal cells, some of which are prolonged into hairs, separated by a septum from the supporting cell. The structure of the vegetative tissue of a simple branch remains * Comptes Rendus, xcvi. (1883) pp. 390-2. + Ibid., pp. 518-20. ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 395 unchanged as long as it continues to elongate, whatever the length of the branch ; and the structure of the median region is always the same from the base to the summit. It follows that the tissues at different levels from the vegetative zone indicate the different stages of differentiation in the tissues of any given level of the median region of asimple branch. The cone of growth of a simple underground branch never has a pileorhiza ; it is of exogenous origin. The conclusion drawn from these observations is that the simple underground branches of Psilotum are stipites with a single central vascular bundle; these stipites have no appendages or roots, and perform the physiological function of roots. In certain regions the plant is therefore reduced to a condition of extreme simplicity ; the stipes playing the part of a root; and the resemblance to a true root is extremely close. Among the Lycopodiacez, finally, there are some species entirely destitute of root. Muscineee. Male Inflorescence of Muscineee.*—H. Leitgeb points out that the order of development from the lower to the higher forms of Muscinez is indicated by the position of the sexual reproductive organs on the vegetative shoots. The advance may be described as an acropetal movement of development; the reproductive organs originating in segments nearer and nearer to the apex as we ascend in the scale, The shoot loses in consequence more and more of its vegetative character, and becomes differentiated as a special fertile shoot, which _ again becomes more and more shortened. In the lowest forms of Hepatice, the Ricciez and Riellez, the vegetative shoot assumes at particular times reproductive functions without essentially altering its character. A good example of a higher stage is afforded by Plagiochasma, where the transformation is indicated by the reduction of the assimilating tissue. In the greater number of Muscinez we get the still higher stage of development, where the vegetative shoot closes with a special “inflorescence ” of sexual organs, while in Mar- chantia and Lunularia a still more complete differentiation of the fertile shoot takes place. lLeitgeb then states that in the true mosses also the first archegonium is derived from the apical cell, and there- fore forms the direct conclusion of a vegetative shoot; and argues that in Polytrichum the male inflorescence is composed of partial inflorescences, each of which corresponds to a reduced lateral branch ; the leaves being simple protective organs to the antheridia. Antheridium of Hepatice.t—H. Satter describes the structure and development of the antheridium in Pellia, Monoclea, and Corsinia. In Pellia epiphylla the antheridia are imbedded in the thallus, as in Marchantiacee, but are of the true Jungermanniacee type; from which he concludes that the depression of the antheridium has no in- fluence on its structure. In Monoclea and Riella, on the other hand, * Flora, xv. (1882) pp. 467-74. + SB. K. K. Akad. Wiss. Wien, Ixxxvi. (1882). See Bot. Centralbl., xiii. (1883) p. 227, 396 SUMMARY OF CURRENT RESEARCHES RELATING TO the Marchantiaceew type of antheridium occurs. The author considers, therefore, that the mode of development of the antheridium cannot be used as a systematic character. The abnormal structure in Corsinia is regarded as a reversion, and the mode of development in the Junger- manniacee is the older phylogenetically. Characee. Monograph of Characee.*—A MS. by the late A. Braun, edited by O. Nordstedt, gives a monograph of the species of Characez, in- cluding several forms not previously published. There are here enumerated 70 species of Nitella, 8 of Tolypella, 1 of Lamprothamnus, 3 of Lychnothamnus, and 60 of Chara. In Tolypella nidifica Braun describes, in the mature cells, the original rows of chlorophyll-grains as being no longer clearly distinguishable, their locations being inter- rupted by large, clear, disk-shaped bodies, which, when the chloro- phyll-grains are removed, are seen to be thickenings of the cell-walls. Fungi. Physiology of Fungi.j—Gaston Bonnier and L. Mangin discuss the results of their studies on respiration and transpiration in plants without chlorophyll. Throughout their experiments they found that the volume of oxygen absorbed is greater than that of the carbonic acid produced. Contrary to the results of some other experimenters, they find that, for a given species, there is no sensible variation with a varying tem- perature, and they ascribe the different result to a neglect by others of the consideration of the phenomena of true fermentation. Differ- ences in hygrometric conditions have a sensible influence on the intensity of the respiratory phenomena. Diffused light diminishes the respiratory activity, and the intensity is greater for the rays of higher than for those of less refractive power. In examining into the question of transpiration they placed the fungi under conditions in which the quantity of water absorbed was very nearly equal to that transpired. After having verified the considerable influence of an elevation of temperature and a depression of the hygrometric con- ditions, they made an inquiry into the influence of diffused light, which resulted in the demonstration that transpiration is greater with diffused light than in darkness. Fungus Parasitic on Sponges.t—J. Dufour has examined the black patches which are formed on skeletons of the officinal sponges which have been in use for some time, and in presence of which they often become useless. He finds the appearance to be produced by a minute fungus which disintegrates the fibre of the sponge, blackening it and producing quantities of dark spores. He assigns this form to the genus Torula as a new species, T. spongicola. The spores are round or suboyal, -004 to ‘007 mm. in diameter. The cell-membrane * Abhandl. K. Akad. Wiss. Berlin, 1882 (7 pls.). See Bot. Centralbl., xiii. (1883) p. 41. + Comptes Rendus, xevi. (1883) pp. 1075-8. t Bull. Soc. Vaud. Sci. Nat., xviil. (1882) pp. 144-7, ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 397 of old spores thickens and becomes brown; they often contain a large central vacuole or some oil-drops. Chains of spores or fragments of mycelium are found among them when in situ. When cultivated in a detached fragment of infected sponge beneath a watch-glass, the spores germinate, producing either chains of spores or a mycelium, the ramifications of which produce simple or branched strings of young spores by successive budding (by which the terminal spore is always the youngest). The terminal spore not unfrequently gives rise to a mycelium-thread. The fungus has also been cultivated upon gelatine. The reason why it occurs in dense masses on particular parts of an infected sponge appears to be that at such points occur the masses of bacterian zoogloea and remains of sponge-sarcode, which in point of fact are almost always to be found on damp sponges, and that these present favourable localities for the growth of the fungus. Experiments tend to show the presence of soap to be rather unfavour- able than otherwise to this organism. From the history of the plant it is easy to understand how one sponge infects another. To cure affected sponges they should be soaked for some hours in somewhat strong solutions of carbolic or salicylic acid, or treated with boiling water. Glycogen in the Mucorini.*—In continuation of his observations on the presence of glycogen in various plants, L. Errera now finds it in all the Mucorini which he has examined. In Phycomyces nitens it occurs in the mycelium, fertile filaments, and young sporangia; it appears to pervade the protoplasm, and not to be locally aggregated, as is usually the case in the asci of the Ascomycetes. Its abundance varies in different parts of the cell. When Phycomyces is subjected to the action of strong alcohol, the protoplasm contracts, and expels the glycogen, which then distributes itself through the cell-sap, and can be detected by iodine. In very young filaments the glycogen is distributed through the whole proto- plasm, but is most abundant in the apical region of the cell; and this is especially the case at the moment when the sporangium is about to be formed. It does not diminish during the formation of the sporan- gium; and when this is definitely constituted, but before the separa- tion of the spores, it is very rich in glycogen, and but little remains in the filament. In the formation of the spores it is taken up chiefly by their protoplasmic contents, and not by their cell-wall. It is possible that a certain quantity of glycogen is required for the respi- ratory combustion of Phycomyces, and by the growth of the cell- wall of the filament, sporangium, and spores; but the greater part is taken up by the protoplasmic contents of the spores; it probably exists there partly in the form of glycogen, while a portion is trans- formed into other substances. Mucor Mucedo and stolonifer also contain glycogen, but in smaller quantities than Phycomyces, and it is more difficult of detection. Its distribution through the filaments at different stages corresponds to * Bull. Acad. R. Sci. Belg., li. (1882) pp. 451-7. + See this Journal, ii. (1882) p. 824. 398 SUMMARY OF CURRENT RESEARCHES RELATING TO that of Phycomyces ; the spores are coloured by iodine a mahogany brown. In WM. stolonifer it is especially difficult to detect, because of the extreme sensibility of the protoplasm to coagulate with iodine ; it permeates the protoplasm of the stolons, fertile filaments, and young sporangia. It accumulates locally in opalescent masses, similarly to the epiplasm of Peziza and Ascobolus; the cell-walls of the fertile filaments are coloured a dirty rose by iodine. M. Errera also records the occurrence of glycogen in Pilobolus erystallinus, and in other species of the same genus; and in Cheto- cladium Jonesti, Piptocephalis Freseniana, and Syncephalis nodosa and minima. As a control experiment, glycogen was extracted from the Phyco- myces, by a method which is described in detail, and recognized by the ordinary chemical tests. Hetereecism of the Uredines.*—C. B. Plowright gives his ex- periments on the connection of certain ecidial and teleutosporic forms of Uredinee. His experiments were started in 1881 with cultures of the spores of Aicidium Berberidis on wheat; but as Uredo linearis, which is the uredo-stage of Puccinia graminis, appeared on the control plants as well as on those on which the ecidial spores were sown, he was not able to confirm the connection between Afcidium Berberidis and Puccinia graminis which is accepted by Continental botanists. In 1882 he repeated his experiments on a larger scale, and with a more satisfactory result. In the case of Puccinia graminis, the mildew of wheat, he not only succeeded in producing Uredo linearis on wheat by sowing the ecidial spores, the control plants remaining healthy; but he reversed the experiment, and produced Avcidium Berberidis by sowing the Puccinia spores. He also sowed the spores of Podisoma Sabine and P. Juniperi on pear and Crategus seedlings, and produced Roestelia cancellata and R. lacerata respectively. The spores of Gymnosporangium Juniperi, sent from a distance of several hundred miles, when sown on Sorbus Aucuparia, were followed by a growth of Roestelia cornuta, a species never before seen by Plowright in Norfolk, where the experiment was made. He also experimented with other species of Puccinia, Peridermium, and Uromyces, and suc- ceeded in confirming the views of Continental writers as to their secondary forms, in one instance producing a Puccinia not before known in Britain, and in the case of Uromyces Junci, showing the relation to Aicidium zonale which was suspected by Fuckel. No writer since De Bary has shown more successful results in this difficult subject, and Mr. Plowright deserves great praise for his careful experiments. Except in one series of cultures, the fully developed zcidial form was obtained, and not the spermogonia alone, as had been the case with some other investigators. Although most of the experiments were rather in confirmation of those of other botanists, in a very important respect he has added to our previous knowledge. One great difficulty in the way of accepting the connec- tion between Aicidium Berberidis and Puccinia graminis has been that * Grevillea, xi. (1882) pp. 52-7. See Amer. Journ. Sci., xxv. (1883) pp. 314-6. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 399 the Puccinia is very common in districts where the barberry is un- known, and according to De Bary the Puccinia spores cannot be made to germinate and grow upon grasses. Mr. Plowright, however, was able in a limited number of cases to make the Puccinia spores grow upon wheat, especially on young seedlings. Infectivity of the Blood.*—G. F. Dowdeswell discusses the in- fectivity of the blood and other fluids in some forms of septic disease, and the reputed occurrence therein of an increase of virulence in successive inoculations, and he comes to the conclusion that in the cases in which he has experimented, Davaine’s septichemia in the rabbit and the so-termed Pasteur’s septichemia in the guinea-pig, there is no increase of infective virulence in the septic fluids in suc- cessive generations, either in respect to the minimal quantities required in the incubation period, nor as to any constant difference in the length of the incubation period. Inflammatory products are more variable, and this is probably partly due to differences in the severity of the cases affording the infective matter (Burdon-Sanderson), and partly, as the author states, to constitutional idiosyncrasy in the animal inoculated. In Davaine’s septichemia there can be little doubt but that the microphyte constitutes the actual contagium, but in Pasteur’s septichemia the microphyte is not simply or per se the contagium, though, no doubt, it may modify the pathological con- ditions. The author states that he has relied greatly on the Micro- scope, and he looks to the use of its greatly increased powers for the advancement of our knowledge of this subject. New Species of Micrococcus.t—T. J. Burrill describes M. amy- livorus, found in the tissues of plants, and causing the so-called “fire-blight.” By the action of this organism the stored starch is destroyed by fermentation, and carbonic acid, butyric acid, and hydrogen given off. It may be cultivated in pure starch in water at a moderately warm temperature. M. toxicatus is found in species of Rhus, and is believed to be the peculiar “poison” for which these plants are known. If transferred to the human skin they multiply rapidly, penetrate the epidermis, and give rise to inflammation. M. insectorum has been found in the digestive organs of Blissus leu- copterus; the insect may be sometimes observed to die off in great numbers, and to present every appearance of suffering from a conta- gious disease, of which these organisms are no doubt the true element. The name of WM. gallicidus is given to the organism which appears in the blood of the domestic fowl when suffering from “ chicken cholera,” and which, though often described, does not seem to have been ever named. Similarly the name of M. suis is given to the form which appears to be the dangerous element in “ hog cholera.” Influence of Light on the Development of Bacteria.{ — In con- nection with the sanitary state of the hospital at Melbourne, J. Jamieson has carried out a series of experiments on this subject. He inoculated * Proc. Roy. Soc., xxxiv. (1883) pp. 449-69. + Amer. Nat., xvii. (1883) pp. 319-20. t Proc. Roy. Soc. Victoria, June 8, 1882, 400 SUMMARY OF CURRENT RESEARCHES RELATING TO Cohn’s solution with drops of putrid flesh-liquid full of Bacterium termo. The questions which he endeavoured to solve were :—1l. Whether ordinary diffused light exercises any influence on the de- velopment of bacteria in Cohn’s solution; 2, whether any influence is produced by the direct rays of the sun; 3, whether the direct rays of the sun rapidly kill bacteria in a dry state. In accordance with earlier observatious, it was first ascertained that the bacteria were killed by direct but not by diffused sunlight. Experiment was then made as to the effect of temperature on these results; and the con- clusion arrived at was that at moderate and low temperatures the direct rays of the sun not only do not kill bacteria, but even have no prejudicial influence on their development. This will account for the want of harmony in the results of previous experiments, As regards the effect of direct sunlight on dry bacteria, Jamieson arrived at the conclusion that, under conditions very favourable for rapid and complete drying up,as when the bacteria are freely exposed to both sun and air, they may be destroyed in a comparatively short time, which, however, is not less than from two to four days, even in summer, Any direct influence of the rays of light as such on bacteria must therefore be regarded as not established. Bacteria connected genetically with an Alga.*—Among the alge which abound on the damp walls of greenhouses, one of the com- monest is, according to H. Zukal, Drilosiphon Julianus Ktz., belonging to the Scytonemezx, and distinguished by its thick outer calcareous sheath, which is partially or entirely wanting in places. The fila- ments have a tendency to produce hormogonia of two different kinds. In the formation of the most common kind, the filament within the outer sheath splits up into small pieces, which ultimately escape, and each carries on an independent existence. These develope into filaments which again produce hormogonia ; but in this process the original comparatively thick form of filament is never reproduced ; each resulting filament is slenderer than the last; till finally they become invisible except to the highest powers. The second kind of hormogonium has a fusiform shape, and thick brownish cell-wall, and consists usually of from four to eight cells. These may remain dormant for a long time after their escape from the sheath, and may hence be termed resting hormogonia. On germinating, they reproduce the ordinary thick filaments. The gradually thinner filaments resulting from the ordinary hormogonia manifest a tendency for their constituent cells to sepa- rate within the external sheath in a moniliform manner, which becomes more pronounced in the succeeding generations, the sheath at the same time gelatinizing, and the whole organism assuming a nostoc- like character. The cells finally become differentiated into larger and smaller, and in this state the filament is known as Nostoc parieti- num Rabenh. The cells of the filament eventually separate, and assume the character of an Aphanocapsa. Or in other cases Glao- capsa-like structures result from the nostoc-filaments, which constitute * Oesterr. Bot. Zeitschr., xxxiii. (1883) pp. 78-8 (1 pl.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 401 the Gleocapsa fenestralis ; or very slender threads are produced, the Leptothria parasitica Ktz. The identity of this form with Drilosiphon has been fully established by the author; instances are not infrequent where a filament which is at the base a typical Drilosiphon terminates at the upper end in a Leptothrix thread, then described as Leptothriz muralis Ktz. These leptothrix-hormogonia have a tendency to break up into detached cells, some of which soon assume a rapid motion and partake altogether of the nature of a vibrio. Others again agree altogether with the structure and phenomena exhibited by Bacillus subtilis Cohn, closing with the formation of spores and micrococci. The germination of these has not been followed. Bacterial investigation of Sunlight, Gaslight, and the light of Edison’s Lamp,*—T. W. Engelmann continues his investigation of the quality of different lights, as displayed by the difference in their effect on the assimilating powers of bacteria. He finds that the relationship between the assimilating effects of different wave-lengths of sunlight, and the effect of corresponding wave-lengths of gaslight on green, yellow, and blue-green cells of plants, is the same. The following are given as the numbers for the assimilating effects at four different spots of the prismatic spectrum of sunlight and gaslight respec- tively :— (a.) With Green Cells. ; BC. D. Et 8. F. Sunlight .. 100 (61) 34-0 (56) 13°9 (44) 24°6 (38) Gaslight .. 100 (208) 22°4 (111) 5°6 (105) 3°8 (50) (6.) With Yellow Cells. BC. Dd. Et 6. F. Sunlight .. 100 (50) 55°1 (47) 40°5 21) 40°4 (7) Gaslight .. 100(196) 35°1 (136) 15°5 (65) 7°6 (70) (c.) With Blue-green Cells. Bi C. D. Et b. Sunlight .. 100(29) 75-4 (82) 19-9 (24) Gaslight .. 100(113) 50-7 (99) 7-6 (49) The figures between brackets denote the number of measurements, from the average of which the numbers are derived. If from these numbers the relative assimilating energy of gaslight is calculated in a percentage of the energy of the corresponding wave- lengths of sunlight, the two energies being taken as equal in B} C, the following results are obtained :— With green cells; 65-9 per cent. at D; 40° 3 per cent. at EZ 6; 19°5 per cent. at F. ” 38: ” yellow bb) 63°7 ” ” 18° 8 ” z ae » 68°8 : 38-2 ‘ The coincidence between the corresponding numbers in these three rows is so great that, reckoning possible sources of error, they ; * K. Akad. Wetensch. Amsterdam, Nov. 25, 1882. See Bot. Centralbl., xiii. (1883) p. 214. * Ser. 2.—Vot. III. 2D 402 SUMMARY OF CURRENT RESEARCHES RELATING TO may be regarded as identical. It furnishes at the same time an objec- tive proof of the practicability of the bacterial method for quantitative photometric determinations. These figures confirm the long-known result that the energy of gaslicht falls rapidly at the most refrangible end of the spectrum, in comparison to sunlight. This fall does not, however, appear to be so rapid with the clear white flame of a large Sugg’s burner as with a Bunsen burner. The light of an Edison’s lamp, produced by a constant stream from twenty Grove’s elements, has a similar effect to that of a Sugg’s burner. Their relative assimilating energies with a green alga (Scenedesmus quadricaudatus) were determined immediately after one another at four different spots of the microspectrum, as follows :— Bi C. D. * Et OD. F. Gaslight .. 100(5) 15'1(5) 4:2(4) 2°9() Edison’s light 100(5) 15°5(5) 4:3(6) 3:0(6) The absolute energy of Edison’s lamp was somewhat less than that of Sugg’s burner. Microbia of Marine Fish.*—At the zoological station recently established at Havre, L. Olivier and C. Richet have carried on an extensive series of experiments on the presence of microbia in the tissues of living fish. With one or two exceptions, they find these organisms universally present in the peritoneal fluid, the lymph, the blood, and, in consequence, in the tissues. They have all the charac- ters of terrestrial microbia, and are reproduced in the same way, by division and by spores. They are most numerous in the peritoneal fluid, less so in the blood and lymph. The most common form is that of bacilli, longer or shorter, endowed with oscillatory movements; they are coloured by ammo- nium picrocarbonate and by aniline pigments; some are provided with spores, either in the middle or at the extremity of the rod. Movements of Minute Particles in Air and Water.t—C. v. Nigeli discusses the laws which regulate the ascending, descending, and dancing movements and the power of floating of minute particles in air and water, as bearing on the question of the transport of the patho- genous Schizomycetes. ‘The movements depend entirely on currents of air, combined, in the case of descending movements, with the attrac- tion of the earth. If there is no current in the air below a certain minimum rapidity, the air once free of fungus-germs must remain free as long as these conditions last. This minimum rapidity is estimated at 2cm. per second. The movements of minute particles in water are subject to much more complicated laws. The passage of particles such as the Schizomycetes and other fungus-spores from water to air takes place by the drying of moist surfaces, not by simple evaporation from the surface of a fluid; also by the bursting * Comptes Rendus, xevi. (1883) pp. 384-6. + Untersuch. iiber niedere Pilze aus dem pflanzen-phys. Inst. Miinchen, i. (1882) pp. 76-128. See Bot. Centralbl., xii, (1882) p. 345, ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 403 of bubbles, by which particles of water are violently thrown into the air. Miquel’s ‘Living Organisms of the Atmosphere.’ * — Aérial micrography is a study of comparatively recent date, and so beset with difficulties that we hail with pleasure the advent of a work devoted exclusively to the subject, especially from the pen of Dr. Miquel, who for several years, as chief of the micrographic staff at the Observatory of Montsouris, has contributed important articles to the Annuaire de Observatoire de Montsouris, Paris. As far as we know it is the only work that embraces comparative seasonal and statistical data. The first attempts of this kind were made we believe in this country by Dr. R. L. Maddox in 1871, who for several months counted, tabulated, cultivated, and figured the air-borne germs entrapped by a self-acting vane or “ Aeroconiscope,” figured in the Monthly Micro- scopical Journal, June 1870. Owing to the little interest which then existed upon this subject, and the increasing labour it needed, he was obliged to relinquish the study. It was then taken up in a more comprehensive manner in 1872 by Dr. D. Douglas Cunningham of the sanitary service of the Government of India, and the results officially published at Calcutta. The subject has fortunately appeared of such importance to the municipal authorities in Paris, as to lead them to create for it a special department, and they have been most fortunate in selecting Dr. Miquel, who has brought to the task un- tiring energy, skilful manipulative talent, and unbiassed predilections, his sole aim being to arrive by repeated careful observations at some useful data in connection with the floating morbific matter of the air. To attain this object much laborious work is still required. The author now gives us, from his collated researches, a better knowledge of the various microbes to be found in the air, the best method for collecting them and studying their action upon solutions of different materials, and the effect of recognized so-called antiseptics upon the life of the different organisms. After sundry trials Dr. Miquel set up his permanent aéroscope and aspirators at the park of Montsouris, which became the basis for comparisons of the number and kind of microbes found in the air at different localities, the air of sewers, hospitals, cemeteries, and apart- ments, as also that of the laboratory in daily use: and some startling results were obtained. The floating air-dust was collected and ex- amined at every forty-eight hours’ interval. A formula was established for counting the number of spores, &c., found in a given space on the surface of the glass that retained them, and corrected for the quantity of air drawn through the aéroscope in a given time. The dusts that had settled in undisturbed places, in apartments, in the laboratory, &c., were examined and contrasted. The infective powers of the soil and of the waters of the Seine and of sewers were compared, and lastly a method of fractional cultivation in certain special sterilized liquids or broths was adopted. The experiments have accumulated * Miquel, P., ‘Les Organismes vivants de l’Atmosphere,’ Paris, 1883, 308 pp. and numerous figs, PAR Di 404 SUMMARY OF CURRENT RESEARCHES RELATING TO to the number of very many thousands. The effects of rain and dry- ness, heat and cold, upon the number and kind of the atmospheric germs drawn into the aéroscope are given statistically ; the months and seasons are compared amongst themselves and with previous years. Dr. Miquel employs means for comparisons, and shows some interesting coincidences, as the increase in the number of atmospheric germs and the increase of the death-rate at certain times, though he does not say they stand related as cause and effect. Long and patient inquiry is necessary, and an unbiassed judgment in the examination of this special point. It would be impossible in the short space we can devote to it to deal with the details contained in this excellent work, replete with illustrations of different germs and various forms of apparatus employed for collecting, sterilizing, and cultivating. Mention is made of the improvements in the apparatus as the difficulties increased, and we believe that much more delicate and elaborate instruments and selected cultivating fluids are now in use for dealing especially with the bacterial element of the air, to which much attention is at present being given by the medical pro- fession, especially in relation to the bacillus of tubercle. It is to be regretted that a similar department is not created in this country, which is supposed to lead in all matters connected with hygiene, and that some basis upon which to carry out the objects in view is not established by different governments in the hope of attaining, if possible, to better preventive measures against zymotic and contagious diseases. Such works as the present will lead us nearer to the realization of more effective measures for the prevention and extension of disease, whether of plants, animals, or man. Lichenes. Reproductive Organs of Lichens.*—The most recently published part of Minks’s ‘Symbol licheno-mycologice’ treats of the Hys- teriacee, Acrospermes, and Stictidee. The author still maintains his opposition to the view that a lichen is a compound organism, made up of a fungus and an alga. On the asci and paraphyses together Minks bestows the term “thalamium”; the “thecium” being that portion of the apothecium which includes these organs. The structure of this portion of the lichen may be referred to three different types:—(1) the asci and paraphyses are both fertile hyphe, which, in the latter case, have undergone arrest of development ; and there are all intermediate stages between the two. (2) The paraphyses are formed a shorter or longer time before the fertile hyphe. They are at a certain period indis- tinguishable from the hyphz of the fundamental tissue of the fructifi- cation, and there is here no true thalamium. To this class belong the true Stictidee and the greater part of the Hysteriacee. (3) Certain genera exhibit an intermediate structure between the first and second. * Minks, A., ‘Symbol licheno-mycologice.’ Part II. Cassel and Berlin, 1882. ~ ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 405 The structure and mode of formation of the spores are described in detail ; and it is shown that in the anthonimorphous type (Hysterium Smilacis, Stictis versicolor, &c.) the mother-membrane takes no part in the abstriction of the spores; but that a new membrane is formed, the old one becoming gelatinized. The formation of the multi- cellular filiform spores of Habrostictis rubra, Stictis nivea, &c., is also described in detail. The germination is described of the spores of Lophium leviusculum. After the destruction of the asci, the spores remain for a shorter or longer time in the fructification, where they germinate ; passing over ultimately into a chroolepis-like gonidema, and not, as would be the ‘case if Schwendener’s hypothesis were true, developing into a fungus. The two different forms of ascus correspond to the two different forms of spore. When the ascus has a double wall, the inner layer of which ultimately gelatinizes, then the spore has only a single membrane ; while when the ascus has only a single wall, the spores have a double membrane, the outer layer of which gelatinizes. Algee. Chromatophores of Alge.*— By the term Chromatophores, ‘F. Schmitz designates chlorophyll-bodies, coloured (not green) pigments, and other analogous colourless bodies. With the exception of the Phycochromacee, all alge possess chromatophores—the colour never being due to a green cell-sap—though they are often difficult to detect from the delicacy of their envelope or from their being concealed by other cell-contents. The form of the chromatophores is very various, but remains constant for the same species, and furnishes also distinguishing characters for the genera. Their arrangement is either irregular or more or less regular. In the latter case they may form straight rows, as in Characez ; beautiful nets, as in the medullary cells of the stem of Laurencia, &c.; or curves, as in many Floridex, &e. &c. They are never in direct contact with the cell-wall or cell-sap, but are always surrounded by a thin, often scarcely perceptible layer of protoplasm. The living chromatophore has, as a rule, a perfectly homogeneous appearance; but those of Spircgyra majuscula exhibit, under high powers, an evident punctation. A similar structure is often visible after fixation with picric acid; in other cases they appear, after hard- ening, to consist of a uniformly dense and very opaque substance. The wide-meshed reticulate appearance which they assume after treatment with acids and other reagents is the result of dis- organization. The colourless ground-substance of the chromatophores agrees altogether in its reactions with the cell-protoplasm, and is simply a portion of it adapted for special functions. Sometimes it constitutes the whole chromatophore, which is then colourless; but this, which is very frequent with the higher plants, occurs but rarely with alge. _ * Schmitz, F., Die Chromatophoren den Algen, 180 pp., 1 pl., Bonn, 1882. See Bot. Centralbl., xiii. (1883) pp. 289-94. 406 SUMMARY OF CURRENT RESEARCHES RELATING TO As a rule they are permeated by green, brown, or red pigments, with which oily substances are possibly mixed. The chromatophores of certain groups of alge are characterized by containing a colourless strongly refractive substance, which exhibits a striking resemblance to the chromatin-bodies of the cell-nucleus in its reactions, and espe- cially in its behaviour towards pigments. These bodies, which are of by no means universal occurrence among alge, and which have elsewhere been observed only in Anthoceros, are termed by the author Pyrenoids. Pyrenoids occur in brown, red, and green alge; they have usually a spherical form, and are imbedded, either singly or in rows, in the substance of the chromatophore. In the green alge they are com- monly surrounded by starch, and then constitute the starch-generators. They result from the formation of starch-grains in the substance of the chromatophore, in close proximity to the pyrenoid; they are at first distinct, but finally coalesce into a hollow sphere. True starch- generators are wanting in the red and brown alge and in Euglena. Pyrenoids are capable of growth and of division; they result from the division of other pyrenoids, rarely from rejuvenescence. They divide by constriction. When enveloped by a layer of starch, com- pound pyrenoids sometimes arise from division, without the envelope dividing at the same time. The chromatophores vary in form, size, and colour according to their age. In young cells they are often smaller, paler, and of simpler structure than in the mature parts of plants; in other cases they lose their colour, as in many hairs and rhizoids, and in secondary meristem. In the antheridia of Characez they are at first colourless, afterwards red. They have only a limited power of growth before dividing. They divide either by constriction or bisection ; but there is no sharp distinction between the two modes; or occasionally by multisection. The division of the pyrenoid or starch-generator pre- cedes that of the chromatophore. The chromatophores always increase in number by division, never by rejuvenescence from the cell-protoplasm ; as can easily be proved in the simpler forms; with greater difficulty in the case of multi- cellular alge. The chromatophores of apical cells and of meristem are the direct result of the division of similar structures occurring in the reproductive cells. In certain cases, as in male sexual cells and in many hairs, they are resorbed. Where both sexual cells contain chromatophores, they may either coalesce or remain distinct after conjugation. The author regards the chromatophores as an essential constituent of the cell in alge, never absent except when the cell is destined to a special biological function, for which their possession would be unnecessary. As regards inclosures in the chromatophores, true starch-grains oceur only in the green alge, and there in most species. As a rule it is only green—but in the central cells of Characez colourless— chromatophores that have the power of forming starch-grains. They are either distributed uniformly through the entire mass of the ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 407 chromatophore, and then may ultimately completely replace it, or are formed only on the surface of the pyrenoids. Both modes may occur in the same chromatophore. The starch-grains of Floridez differ from ordinary starch-grains by the brown or red colour imparted to them by iodine. Their mode of formation is also peculiar, being produced not inside but outside the chromatophore. In the Pheophycee starch-grains are formed, as in the Floridex, around the chromatophore, but they are not coloured at all by iodine. The “paramyl-grains” of Huglena and similar organisms are chiefly distinguished from ordinary starch by not being coloured by iodine ; they are produced, like the starch-grains of red and brown alge, outside the chromatophore. They form a closed envelope round it, completely resembling that of true starch-generators. The pseudo-starch-generators of certain Floridex, e.g. the Nemaliex, have the same origin. In some chromatophores the starch is replaced by substances soluble in alcohol, occurring in the form of small drops on the surface, never in the interior. They may also occur in addition to starch. Finally, the author compares the chromatophore with the cell- nucleus. Both are composed of a reticulate framework, closely resembling protoplasm in its properties. The nucleoli, or inclosures in the nucleus, agree in their reactions and behaviour with the pyrenoids of many alge. Both arise only by division, never by rejuvenescence. Nuclei and chromatophores may be regarded as two series springing from a common origin, but developing afterwards in different ways to adapt them to different biological functions. Phycochromacee.*—Proceeding with his detailed account of the Phycochromacee, A. Borzi now describes the two families Rivula- riaceze and Chamesiphonacee. The former consists of the following genera :—Calothri« Thr., Sacconema nov. gen., Leptochete nov. gen., and Rivularia Roth. The two new genera are thus described : — Leptochete. Trichomata simplicia, sepius tenerrima, erecta, thallum indefinite crustiforme, tenue, plerumque late effusum effi- cientia; heterocystis nullis. Multiplicatio hormogoniis et conidiis chroococcoideis ex articulorum basalium transmutatione ortis. Three species :—L. crustacea, fonticola, and parasitica. Sacconema. Trichomata irregulariter ceespitoso-ageregata, 2-plura vagina communi fuscescente, lamelloso-stratificata, valde ampliato- saccata, demum apice soluta, involuta et thallum exiguum gelatinosum laciniato-lobulatum constituentia ; pseudo-ramulis brevibus, monili- formibus, discretis, heterocystide basilari globoso instructis ; sporis aureo-fuscis, articulos vegetativos duplo superantibus, exosporio cras- siusculo, scabro. One species :—S. rupestre. The new family of Chamesiphonacee consists of the genera Chamesiphon A. Br., Clastidiwm WKirchn., Cyanocystis noy. gen., and Dermocarpa Crouan. It has the following diagnosis :— * Nuov. Giorn. Bot. Ital., xiv. (1882) pp. 272-315 (2 pls.). 408 SUMMARY OF CURRENT RESEARCHES RELATING TO Algz typice unicellulares, aque dulcis incole, rarius marine, contento phycochromaceo, subhomogeneo, ceruleo vy. violaceo aut chalybeo-purpurascente. Cellule vegetative globose, sepe minute, primum liberze et in familias chroococcoideas consociate, deinde stipite obconico plerumque exiguo, substrato adfixe, et in coccogoniis globosis vy. piriformibus aut plus minus elongato-cylindraceis trans- mutate. Conidia 4—plura in quoque coccogonio, contenti divisione repetita binaria, modo totali, modo partiali et basipeta ortis, demum, membrana matricali ad apicem soluta, raro transverse scissa, liberata. The author prefers the term coccogonium to sporangium for the conidiferous cells of this family. The new genus is described as follows :-— Cyanocystis. Coccogonia globosa aut subglobosa, plerumque ses- silia, substrato arcte adherentia; membrana tenui, dein transverse scissa. Conidia 4—8, raro 16,e contenti divisione totali ad tres direc- tiones alternante orta. One species :—C. versicolor. Bangiacee of the Gulf of Naples.*—G. Berthold publishes a monograph of the species of Bangiacex found in the Bay of Naples, belonging to the genera Bangia, Porphyra, and Erythrotrichia, with the addition of the anomalous genus Goniotrichium. The structure of the thallus in the first three genera is explained in detail, including the non-sexual spores or tetraspores. They are described as having a spontaneous motility for about forty-eight hours after their escape (in the case of Bangia fusco-purpurea), at the expiration of which period they begin to germinate. They do not, however, exhibit any amceboid change of form. The male organs or “ spermatia” of Porphyra and Bangia exhibit a close resemblance to those of other Floridee. In B. fusco-purpurea and P. laciniata they proceed, as a rule, from all the cells of certain individuals; in P. leucosticta from parts only of the thallus, which may be regarded as male; the rest of the thallus producing non- sexual spores or procarps, among which the male cells are dispersed in different ways. There are also intermediate structures between non-sexual spores and spermatia. In Erythrotrichia the spermatia and non-sexual spores are formed in precisely the same way. In none of the genera have the spermatia any spontaneous motility ; in Hrythro- trichia they are larger than in the two other genera. The formation and structure of the female cells or procarps is also described in detail, as well as the process of fertilization, result- ing in the production of cystocarps. The procarp-cells differ in no essential respect from ordinary vegetative cells. The usual number of cystopores formed is 8, the “ octospores” of Janczewski; but they may be only 4 or 2, or possibly only a single one. In female speci- mens of P. laciniata the ripe procarps have a blackish, the ripe cysto- spores a beautiful red colour; while the unfertilized and perishing © procarps go through various green and yellow tints, finally becoming colourless. * Berthold, G., ‘Fauna u. Flora des Golfes von Neapel. 8te Monographie: Bangiaceen. Herausgegeben von der Zoolog, Station zu Neapel.’ 28 pp. (1 pl.). 4to, Leipzig, 1882. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 409 The author regards the non-sexual spores, spermatia, and cysto- spores of the Bangiacez as undoubtedly homologous, the procarp corresponding to the mother-cells of the non-sexual spores and of the spermatia. It follows that the procarp is homologous, not with the oosphere of the Chlorosporee and Melanosporee, but with its mother- cell. i The germination of both kinds of spore has been well followed out. The above details show that the Bangiacez constitute unquestion- ably a lowly organized family of Floridee. The true position of Goniotrichium must at present remain doubtful; the non-sexual spores correspond closely to those of Bangiacee; but no mode of sexual reproduction is known. Spherozyga Jacobi.*—P. Richter now identifies the rare nostoc- like alga Spherozyga Jacobi Ag. with Cylindrospermum polyspermum Ktz.; and since Wittrock has shown good ground for regarding Trichormus Rlfs., Dolichospermum Vhw., Spherozyga Rlfs., and Cylin- drospermum Rlfs., as subgenera of Anabena, it must in future be known as Anabena (Spheerozyga) Jacobi. Algoid Structures in the Coal of Central Russia.j—P. F. Reinsch states that the combustible substance of coal consists of various bodies of constant microscopical composition. They exhibit no crystalline character, but the arrangement of their particles is nevertheless so uniform that it is difficult to assign to them any but an organic origin. They are not completely decomposed and carbon- ized, exhibit a certain elasticity, and with a very dilute solution of caustic alkali they manifest a certain power of swelling, similar to many cartilaginous alge belonging to the Melanospermee and Phycochromacex, as Scytonema, Hormosiphon, and Hopalosiphon ; with iodine they take a distinct yellowish brown colour. These characteristics strongly indicate that they are remains of alge. Along with these bodies are found others, probably unicellular, of triangular shape, and manifesting uniform trisection, the nature of which is more obscure, but which are also probably of algoid origin. They are quite distinct from the spores of vascular cryptogams, with which they are often intermixed. Decomposition of Synedra radians by Caustic Potash.—C. J. Miller calls attention to the action of a solution of caustic potash on the frustules of Synedra radians, fresh gathered, or, at least, in a living state. The solution used is composed of 50 grains of caustic potash dissolved in 1 ounce of distilled water. Having placed the diatoms (more or less intermixed with other forms) in a moist state upon a glass slide, and allowed the mass to get nearly dry, apply the solution of potash freely and cover with thin glass. After the lapse of a few hours (more or less according to tem- perature) it will be seen—in the case of a front view of a frustule— * Hedwigia, xxii. (1883) pp. 3-6. + Flora, Ixvi. (1883) pp. 113-20 (2 pls.). 410 SUMMARY OF CURRENT RESEARCHES RELATING TO that the connective will separate as two fine siliceous films in a curved form, one belonging to one half of the frustule, the other to the other half. In the case of a side view of a frustule in the process of division, the two portions will separate at the extremities, expanding therefrom in a curvilinear form. After a further time it will be seen that the portion of the siliceous shell which contains the striation will be entirely separated from the endochrome, and in many cases greatly curved. After the lapse of 24 or 36 hours, it will generally be noticed that the siliceous portion containing the striation has broken up into fragments which are exactly like the iron cramps of carpenters. In fact, the striation is due to the juxtaposition of a number of these little cramps along the length of the frustule, probably cemented together originally. Synedra radians may be described as a long four-sided box, two of the sides (top and bottom) consisting of a siliceous film without any markings, and the other two sides of a structure made up of cramps holding the upper and lower side in position. Mr. Miiller adds: “I should have liked to illustrate this dis- covery, but any one familiar with microscopical manipulation will be able to see all that I have described better on the stage of the Micro- scope than in a drawing on paper. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. Leiter and Mikulicz’s Gastroscopes, — J. Leiter * has devised a great variety of instruments intended for inspecting various more or less inac- cessible parts of the body, including the mouth, larynx, cesophagus, stomach, intestines, urethra, bladder, vagina, rectum, ear, nasal fosse, &e. They all agree in providing for the introduction of a small electric light into the cavity to be examined, with a special provision for preventing any incon- venience from heat by the circulation of a stream of water—a plan originally suggested by Dr. Bruck. Most of the instruments also provide for the introduction of an objective, which forms an image of the part examined, the image being received by an eye-piece either direct or, where necessary, after being diverted in the proper direction through prisms. Leiter’s original gastroscope in particular was a marvel of ingenuity in the various arrangements for allowing the walls of the stomach to be illuminated and examined by the aid of lenses, but has apparently been found too complicated for practical use, and a simplified form is described by Dr. J. Mikulicz + (with a great elaboration of detail on all points), which has been devised by him in collaboration with Herr Leiter. The tube A (fig. 70) is 65 em. long and 14 mm. thick, and is bent at F atanangle of 150°. AtB is the platinum wire for the electric light covered with a glass plate and connected, by wires running up the tube, with the key C and a Bunsen battery. Two water-tubes also run up the main tube, their ends being shown at D, a constant stream of water being maintained during the observation so as to prevent the lower end of the tube becoming heated. There is an additional tube for pumping water into * Leiter, J., ‘ Elektro-Endosko- pische Instrumente. Beschreibung und Instruction zur Handhabung der von Dr. M. Nitze und J. Leiter construirten Instrumente und Appa- rate zur direkten Beleuchtung menschlicher K6rperhéhlen durch elektrisches Gliihlicht.’ 65 pp. and 82 figs., 4to, Wien, 1880. Cf. also Engl. Mech., xxxiii. (1881) pp. 27-8 (9 figs.). + Mikulicz, J., ‘Ueber Gastro- skopie und Oesophagoskopie.’ (Sep. Repr. from ‘Wiener Medizinischen Presse, 1881.) 32 pp. (3 figs.) 8vo, Wien, 1881. = SSS eee Ve GEtPER= pre MICULICZ———\ Fic. 70. 422 SUMMARY OF CURRENT RESEARCHES RELATING TO the stomach, which commencing at the indiarubber balls K passes into the main tube at L and is continued to L’ where there is a small aperture. The optical apparatus consists of a prism and an objective at E (the prism being right-angled and acting as a reflector to transmit the rays from the side of the instrument up the tube), a second prism at the bend at F, and an eye-piece at G. ‘To prevent the glass plate at B from being smeared whilst the instrument is passed down the cesophagus a metal shutter H slides over it and can be drawn back by moving the collar at J. The fact is enforced in italics that the instrument can be intro- duced into the bottom of the stomach without difficulty, and fig. 69 is given in illustration of the statement; another figure showing the advantage of the bent end in allowing different parts to be illuminated and observed by simply rotating the tube, the stomach being distended to facilitate the excursions of the tube. The author’s pamphlet con- tains not only a very full description of the instrument, but minute directions for its use. Dr. T. Oliver describes * a successful experiment of examining the interior of a patient’s liver by one of the small Swan incandescent lamps described by Mr. Stearn ante, p. 29. The apparatus used was an electro-plated brass tube 93 in. by 11-16ths in., closed at the lower end by glass, down which was inserted a narrow cylinder carrying a lamp and wires. Mr. J. B. Payne (a Fellow of this Society), who devised the arrangement, considers it to be much simpler than Leiter’s platinum wire as it gives a perfectly pure light and developes less heat. He says “a Swan’s electric lamp is used—the filament of which is carbon, and rendered incandescent by means of battery power. It is hermetically sealed in a glass shade; and water, con- veyed to and fro through very small brass tubes, is made to circulate round the lamp. The light from this lamp is perfectly pure, and exhibits the condition of things in their true and natural colour. For prolonged observation I should prefer to use either a Grove’s or Bunsen’s battery, but in the demonstration just referred to, four cells of a modified Leclanché battery were employed and answered ad- mirably. It is advisable to have as great a pressure as possible for the water supply, so as to insure perfect circulation, and for this I suspended from a hook fixed near the ceiling of the room a tin can containing water, connecting it with the brass tubes by means of lengths of indiarubber tubing.” Cobweb Micrometers.j—Mr. G. F. Dowdeswell prefers a cobweb micrometer which has the second web movable instead of being fixed as in the usual form. This both saves time and promotes accuracy, as when only one web is movable it is almost impossible, by means of the mechanical stage, to bring an object into exact contact with the fixed web, which is done at once with ease and certainty by the second movable one. * Brit. Med. Journ., 1883, Jan. 27. + Quart. Journ. Micr. Sci., xxiii. (1883) p. 337. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 423 Chevalier’s Camera Lucida.—Dr. Carpenter describes * a form of this camera intended to be used with the horizontal Microscope. Fig. 71 shows a modification de- signed by Dr. A. Chevalier} for a Fig. 71, ( vertical Microscope. The reflect- ing prism is made much larger and is brought close to the small perforated metal speculum. The whole field is readily seen without any part being obstructed. iin Grunow’s Camera Lucida.— This camera (ante, p. 120) was the subject of discussion at the May meeting of the Society, and for convenience of reference we add fig. 72, showing its con- struction. A and B are the lenses of the eye-piece; DCE, DFE, and GHJ three right-angled prisms, the first two having their hypothenuses cemented together with balsam to make a cube. Prior to cementing, the Fic. 72. upper of the two prisms has its hypothenuse silvered, but a small spot, not more than 1-16th in. in diameter, is afterwards denuded of silver as nearly as may be in the geome- trical centre of the silvered face at M. The prism GHJ is movable on an axis, to pro- Ss vide for its use when the instrument is either upright or inclined. Rays from Z, the table, ! are totally reflected from the face G H (say at } K), and entering the upper prism, are reflected ! to the eye at X by the silvered surface D E, | while the object is seen at the same time : through the unsilvered spot in the middle of H | I z =e the same face. A writer in the ‘ English Mechanic’ { says that it is not a sine quad non to silver the surface, but the effect is wonderfully im- proved by doing so, the blue tint that other- wise appears to cover the object being almost entirely eliminated by the white reflection from the silver; and that this form of apparatus can be used with less straining and eye-fatigue than any he ever tried. Holle’s Drawing Apparatus.$—The device of Dr. H. G. Holle differs essentially from all other forms of drawing apparatus, and was * and Sections of Rocks and Fossils. Instruments and Appliances for Mounting, &c. Sciopticon, with addi- tion for using’ microscopic objectives. Glass Photograms. - Pie Catalogue No. IX., Gratis and Post-free. AS ER EIN OC ; PREPARER OF MICROSCOPIC OBJECTS, Late of 80, Russell Road, Seven Sisters’ Road, London, N.., : : HAS REMOVED TO 5 : FERNDALE, BATH ROAD, WOKING STATION, SURREY. Stee 3 JUST PUBLISHED. Say: : HILEFSBUCK ZUR AUSFUHRUNG - MIKROSKOPISCHER UNTERSUCHUNGEN ek : _ IM BOTANISCHEN LABORATORIUM. ; Von WILHELM: BEHRENS. * 2 Plates and'132 Wood Engravings, 8vo, 12s.; Cloth, 13s. 6d. ~ ‘Fhis book has been written with a view to its use by the Botanical Microscopist on his working table. It + contains the principal methods of preparing and conserving Botanical objects, Is also treats in extenso the so-called “ Botanical Micro-Chemistry.”— © - _- Brunswick: SCHWETSCHKE & SON. London and Edinburgh: WILLIAMS & NORGATE, : JAMES HOW & CoO., Strate _ SUCCESSORS TO GEO. KNIGHT &-SONS, . 73, FARRINGDON ST. (late of 2, Foster Lane, and 5, St, Bride $t,), orig See pe .. HOW’S ‘MICROSCOPE LAMP. 'THE MINIATURE MICROSCOPE LAMP. - HOW'S STUDENTS’ MICROSCOPE, £5 5s. THE POPULAR BINOCULAR MICROSCOPE, £12 19s, Air eo eens © Rocx SEcTIONS AND OTHER Microscorie Opsects, 5 ( 16 ) W. WATSON & SON’S NEW MICROSCOPE STAND (PATENTED), The most perfect Instrument for the employment of light at great angle of obliquity ever introduced. W. & S.’s PATENT MECHANICAL STAGE Is graduated to degrees—Rotates concentric, and will revolve completely round, with any instrument—has mechanical movements in vertical, horizontal, and oblique directions, and is the thinnest and most perfect mechanical stage ever introduced. See description in the Royal Microscopical Journal, April and June, 1881. Tustrated Catalogue of above, and all descriptions of Microscopes and Apparatus, post free 2d. W. WATSON & SONS, 313, High Holborn, London, W.C. TO MiIiCROSCOPISTS. PREPARATIONS OF FRESH WATER ALGZ, Including Desmiprez, DrATOMACEZ, and CépoGoNniEz; also Funer, Mosszs, &., showing well their Structural Development and Mode of Reproduction, 15s. per doz. slides. A few very good sets of Opaque Licuens, suitable for low powers with the Binocular. These will have especial interest to the Student, showing the true character of the thallus, its colour and mode of growth, and as type specimens from which Herbaria may be named will be invaluable. Avpiy: W. JOSHUA, F.LS., CIRENCESTER. New and Second-hand Microscopes, Objectives, and Accessories. A Large Assortment by Ross, Beck, Cottrns, Swirt, and other first-class Makers, on Sale, at a GREAT REDUCTION IN PRICE. MICROSCOPICAL OBJECTS in great variety. Spécialité. PuystorocicaL and PATHOLOGICAL TISSUES, A choice variety of prepared Physiological Sections ready for Mounting. PHOTOGRAPHIC LENSES, CAMERAS, and APPARATUS, by Ross, DaLiMEYER, and all other esteemed Makers. Largest, Cheapest, and Best Stock in London. New Cata.ocuss Post Free. HUNTER & SANDS, 20, CRANBOURN STREET, LONDON. LIVING SPECIMENS FOR THE MICROSCOPE. THOMAS BOLTON, 57, Newhall Street, Birmingham. SPECIMEN TUBE, ONE SHILLING. A Series of TWENTY-Six TUBES in course of Six Munths (or as required) for a SUBSCRIPTION, in advance, of £1 1s. Portfolio of Drawings, Eight Parts, One Shilling each. Hints on the Preservation of Living Objects, and their Examination under the Microscope, 3a. UNMOUNTED OBJECTS FOR THE MICROSCOPE. PREPARED FOR MOUNTING, WITH INSTRUCTIONS, Will be ready immediately— Series D*—24 Australian Zoophytes, Series E*—12 Palates of Mollusca. Series F*—24 Mosses and Hepatics. : PRICE 2s. EACH SERIES, POST-FREF, 2s. 1d. Brown Cement, the best for Microscopic Work, post-free, 1s. 3d. Every requisite for Microscopic work. EDWARD WARD, 29, BURLINGTON STREET, OXFORD ROAD, MANCHESTER. Sct GRO AE A PREG EEA PEER. CE SO EN SEIS IRS I ORES I TE PELE - MICRO-PETROLOGY. : A Large Series of Rock Sections, comprising Anamesite, Aplite, Basalt, Diabase, = Diorite, Dolerite, Elvans, Gabbro, Gneiss, Granite, Granulite, Lava, ins, Liparite, Napoleonite, Neppelirite, Obsidian, Pikrite, Porphyry, Phonolite, Quartzite, Rhyolite, Syenite, Tachylite, &c., 1s. 6d. and 2s.each. - eee Sections of Organic Rocks, showing Foraminifera, Sponge Structure, Corals, Shells, &c, __ es THOMAS D. RUSSELL, 48, Essex Street, Strand, W.C. reps, ( WW ) International Exhibition Prize Medals and Awards, 1851, 1855, 1862, 1873, 1878; and The Imperial Austrian Francis Joseph Order, for Excellence and Cheapness, _M. PILLISCHER’S NEW MICROSCOPE, “THE INTERNATIONAL,” Is furnished with B and C Hye-pieces; a 5-8 and 1-7 Object-glasses of high defining ae penetrating quality, combining (by a draw-tube) a series of eight different powers, from 50 to 420 diameters; bull’s-eye con- denser; revolving diaphragm; pair of tweezers; plate- Blass Slips and thin es Blass ‘and a well-made mahogany box, 10 by 6 by 4, with lock and key ... .. .. Price £7 10s. With the addition of A Bye-piece, 14 or 2 in. Opieeerins. Polatising eaaaraens oa * Selenite, and a Camera Lucida... -» Price £10 10s, And all the Apparatus. and Accessories, as described above, with the addition of a D Bye-piece and a 1-9 Object-glass, giving a series of twenty- oat magnifying powers, from 15 to 1000 diameters .. . .. Price £14 Os. A Glass Stage, to prevent the instrument from being affected’ by the use of corrosive - chemicals, to any of the above instruments, extra .. . eetcals 12s. 6d, Illustrated Descriptive Catalogue on application to ss, NEW BOND STREET, LONDON, Ww. MICROSCOPICAL SPECIALITIES, ILLUSTRATING THE STRUCTURE, GROWTH, AND REPRODUCTION OF PLANTS. SPECIAL EDUCATIONAL SHTS, illustrating Sachs’ and Thomé’s Text-Books of Botany, the preparations being copies of figures in those works. A large assortment of miscellaneous Botanical Objects. Test Diatoms mounted in Monobromide of Naphthaline. Chas. V. Smith, Carmarthen. SPECIAL NOTICE. POWELL AND LEALAND’S NEW OIL IMMERSION CONDENSER can be adapted to any Microscope, ee resolves all the most difficult test objects—price Two Guineas. MICROSCOPES from £11 11s. to £200. The £11 11s. Instrument consists of l-inch and }-inch Object-glasses, with Apertures of 30 and 95 deg. respectively, coarse and fine Adjustment, Glass Stage and Bull’s-eye Condenser, fitted in mahogany case, and is most suitable for Students, Brewers, &e. WATER AND OIL IMMERSION LENSES. ‘Manufactory : 170, EUSTON ROAD, LONDON, N.W. CHAS. COLLINS: HISTOLOGICAL MICROSCOPE, With 1-inch and }-inch Objectives of splendid Definition, : Eye-piece, and Case, £5 10s. Full particulars free per post. ‘Harley Binocular Microscopes, Dissecting Microscopes, Lamps, Objectives, Thin Glass ob Oia ~ Slips, Mediums, and every requisite for the Study. THIRTY- SIX PAGE ILLUSTRATED CATALOGUE ON APPLICATION. CHARLES COLLINS, i AST, Great Portland Street, London, W. W. P. Corus’ Science Book Depit, adjoining the above. Catalogue on application. ¢ 18.) F. E. BECKER & CO’S PRICE LIST OF MICROSCOPIC REAGENTS AND SUNDRIES (Among the former, Stains for Bacillus Tuberculosis and all the latest novelties for Staining) will be sent post-free on application to— F. E, BECKER & CO., 34, Maren Lanz, Covent Garpren, Loypoyx, W.C. MICROSCOPIC OBJECTS. Classified Catalogue. NEW EDITION FOR 1880. Post Free and Gratis, Specimens of the highest attainable perfection in every branch of Microscopy. New and Rare Diatomacex. Test and Binocular Objects. Modller’s Typen Plattes. Microscopes, Achromatic Objectives, and all Materials and Instruments for Mounting. EDMUND WHEELER, 48B, Tollington Road, Holloway, London, N. Just Published, PARTS I. and II, of JOHN WHELDON’S ZOOLOGICAL CATALOGUE, Containing Entomology, Ornithology; Mammalia, Anthropology, Sporting, General Zoology, and Transactions of Scientific Societies. HAY BE HAD, ON APPLICATION, FOR TWO STAMPS. ~ JOHN WHELDON, 58, GREAT QUEEN STREET, LONDON. SwWwWierT & SON Are now adapting to their ‘‘ Challenge ”’ and other Microscopes, A NEW THIN MECHANICAL STAGE AND PATENT COARSE AND FINE ADJUSTMENTS, : Also SWINGING SUBSTAGE RADIAL ILLUMINATOR, as well as all the latest Improvements and Additions to the Microscope. - Catalogue fully Illustrated, and Circular, containing particulars of the above, by post. for six stamps, or mailed abroad free. - UNIVERSITY OPTICAL WORKS, 81, TOTTENHAM COURT ROAD, — a LONDON, W.C. (formerly of 43, University Street). NOW PUBLISHING. STUDIES IN MICROSCOPICAL SCIENCE. — Edited by ARTHUR ©. COLE, F.R.MS., &c., assisted by several Eminent Specialists. _ A Wrex ty Periopicat for the use of Students, Teachers, Professors, and the Medical Profession, and others - interested in the progress of the Natural Sciences. Each Number is illustrated and accompanied by— — - (1).A Microscopical preparation of the highest class and most perfect finish; (2) A description of the Speci-» - ~ ee men, the methods of its jon a5 a means of Study, the literature concerning it, &c.; (3) A Chromo- ~~ lithographed, Photograp! or Engrayed drawing or diagram of the Object, in the execution of which — Scientific accuracy and artistic detail are specially observed. The terms of subseription, payable strictly in advance, including Postage, are—In Great Britain, Quatbesty, a , ee 63.645 © 11, 4s.; Half-yearly, 21. 4s.; Yearly, 41. 4s. Abroad, to Countries within Postal Union, Quarterly, 1 Half-yearly, 21. 88.; Yearly, 41. 12s. 6d, Those desirous of receiving a smaller number of Specimens, and — of fortnightly, may, for 21. 2s. a year, receive either the series of 26 HisToLocicaL Preparations or the 26 ~ BOTANICAL and PeTROLOGICAL Szctions, together with their accompanying essays and illustrations. (Abroad ee this Subscription will be 21. 6s. 6d.) ; Bo Subscriptions to the Editor, Mr. A. C. Corz, St. Domingo House, Oxford Gardens, London, W. ~ Se & ( 19 ) Council Medal and Highest Award, Great Exhibition, London, 1851. Gold Medal, Paris Exposition, 1867. Medal and Highest Award, Exhibition, London, 1862. Medal and Diploma, Centennial Exhibition, Philadelphia, 1876. Medal and Diploma, Antwerp, 1878. Gold Medal and Diploma, Paris Exposition, 1878. Medal, Highest Award, Sydney, 1879. ROSS & CO., MANUFACTURING OPTICIANS, 112, NEW BOND- STREET. (FACTORY, BROOK STREET), LONDON, W. MICROSCOPES, OBJECT-GLASSES, APPARATUS, MICROSCOPIC PREPARATIONS. NEW ‘DESCRIPTIVE CATALOGUE. ON APPLICATION TO — ROSS & CO., 112, NEW BOND STREET, W. (One door from Brook Street), REMOVED FROM 164, NEW BOND STREET. ESTABLISHED 1850. THE ROYAL MICROSCOPICAL SOCIETY. (Founded in 1839. Incorporated by Royal Charter in 1866.) The Society was established for the communication and discussion of observations and discoveries (1) tending to improvements in the con- struction and mode of application of the Microscope, or (2) relating to Biological or other subjects of Microscopical Research. It consists of Ordinary, Honorary, and Ex-officio Fellows. Ordinary Fellows are elected on a Certificate of Recommendation signed by three Fellows, stating the names, residence, description, &c., of the Candidate, of whom one of the proposers must ‘have personal know- ledge. The Certificate is read at a Monthly Meeting, and the Candidate balloted for at the succeeding Meeting. The Annual Subscription is 2]. 2s., payable in advance on election, and subsequently on Ist January annually, with an Entrance Fee of 21, 2s. Future payments of the former may be compounded for at any time for 311.10s. Fellows elected at a meeting subsequent to that in February are only called upon for a proportionate part of the first year’s subscription, and Fellows absent from the United Kingdom for a year, or permanently residing abroad, are exempt from one-half the subscription during absence. Honorary Fellows ae to 50), consisting of persons eminent in Microscopical or Biological Science, are elected on the recommendation of three Fellows and the approval of the Council. Ex-officio Fellows (limited to 100) consist of the Presidents for the time being of such Societies at home and abroad as the Council may recommend and a Monthly Meeting approve. They are entitled to receive the Society’s Publications, and to exercise all other privileges of Fellows, except voting, but are not required to pay. any Entrance Fea or Annual ‘Subscription. The Council, in whom the management of the affairs of the Society is vested, is elected annually, and is composed of the President, four Vice- Presidents, Treasurer, two Secretaries, and twelve other Fellows. The Meetings are held on the second Wednesday in each month, from October to June, in the Society’s Library at King’s College, Strand, — iy (commencing at 8 p.m.).. Visitors are admitted by the introduction of | ellows. In each Session two additional evenings are devoted to the exhibition of Instruments, Apparatus, and Objects of novelty or interest relating to | _ the Microscope or the subjects of Microscopical Research. j The Journal, containing the Transactions and Proceedings of the Society, with a Summary of Current. Researches relating to Zoology and Botany (principally Invertebrata and Orpen): Microscopy, &c., is — published bi-monthly, and is forwarded gratis to all Ordinary and Ex-officio — Fellows residing in countries within the Postal Union. The Library, with the Instruments, Apparatus, and Cabinet of — Objects, is open for the use of Fellows on Mondays, Tuesdays, Thursdays, — and Fridays, from 11 a.m. to 4 P.m., and on Wednesdays from 7 to 10 p.m. — It is closed during August. in . Forms of proposal for Fellowship, and any further information, may be obtained by — application to the Secretaries, or Assistant-Secretary, at the Library of the Society, King’s — allege, Strand, W.C. poe SLES FPS EES PT Oa Sa FPO Moe Laceres a> Tn 8 9185 00266 | Bie Ban Ma Bt Wa rene ES atin ‘ ICS SN BEN a Oe LTE DA EY ad LOE STEEN E SEES RS GF po ge Re! ee tee er oe bx oe x 3 és , 7 ie il i OT ay Serial A ral hee ; . he!