HARVARD UNIVERSITY. ^yj/fccx/U: viL — jxk,7\mxO^ ^) ) Journal OF THE Royal Microscopical Society; CONTAINING ITS TRANSACTIONS AND PROCEEDINGS, AND A SUMMARY OF CURRENT RESEARCHES RELATING TO Z O O L O O ~¥T AND BOTANT (principally Invertebrata and Cryptogamia), MICROSCOPY, Szo. Edited by A. W. BENNETT, M.A. B.Sc. F.L.S. Lecturer on Bota?iy at St. 7 homos'1 s Hospital ; WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND R. G. HEBB, M.A. M.D. F.R.O.P. J. ARTHUR THOMSON, M.A. F.R.S.E. Lecturer on Pathology at Westminster Lecturer on Zoology in the School of Medicine , Hospital , I Edinburgh , FELLOWS OF THE SOCIETY. FOR THE YEAR 1897. s LONDON : TO BE OBTAINED AT THE SOCIETY’S ROOMS, 20 HANOVER SQUARE, W. ; of Messrs. WILLIAMS & NORGATE ; and of Messrs. DULAU & CO. • / THE (Established in 1839. Incorporated by Eoyal Charter in 1866.) The Society was established for the promotion of Microscopical and Biological Science by the communication, discussion and publication of observa- tions and discoveries relating to (1) improvements in the construction and mode of application of the Microscope, or (2) Biological or other subjects of Microscopical Research. It consists of Ordinary, Honorary, and Ex-officio Fellows of either sex. Ordinary Fellows are elected on a Certificate of Recommendation, signed by three Ordinary Fellows, setting forth the names, residence, and description of the Candidate, of whom the first proposer must have personal knowledge. The Certificate is read at two General Meetings, and the Candidate balloted for at the second Meeting. The Admission Fee is 2 1. 2s., and the Annual Subscription 2/. 2s., payable on election, and subsequently in advance on 1st January annually, but future payments may be compounded for at any time for 317. 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. The annual Subscription of Fellows permanentlyresiding abroad is 1/. 11s. 67., or a reduction of one-fourth. Honorary Fellows (limited to 50), consisting of persons eminent in Microscopical or Biological Science, are elected on the recommendation of five Ordinary Fellows and the approval of the Council. Ex-officio Fellows (limited to 100), consisting of the Presidents for the time being of any Societies having objects in whole or in part similar to those of the Society, are elected on the recommendation of ten Ordinary Fellows, and the approval of the Council. The Council, in whom the management of the property and affairs of the Society is vested, is elected annually, and is composed of the President, four Vice-Presidents, Treasurer, two Secretaries, and twelve other Ordinary Fellows. The Meetings are held on the third Wednesday in each month, from October to June, at 20 Hanover Square, W. (commencing at 8 p.m.). Visitors are admitted by the introduction of Fellows. In most Sessions there is a Conversazione 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, and a Summary of Current Researches relating to Zoology and Botany (principally Invertebrata and Cryptogamia), Microscopy, Ac., is published bi-monthly, and is forwarded post-free 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 daily (except Saturdays), from 10 a.m. to 5 p.m. and, irom November 1st to June 30th, on every Wednesday evening from G p.m. nicl Septe ^ Ce^ ^ee^nS nights). It is closed- for four weeks during August F°rr)}s of proposal for Fellowship , and any further information , may he obtained by 20* Hanover ? ^ feretories, or Assistant-Secretary, at the Library of the Society, a 2 af r o it HIS ROYAL HIGHNESS ALBERT EDWARD, PRINCE OF WALES, K.G., G.C.B., F.R.S., Ac. |)ast-|)rcsibents. PRected *Sir Richard Owen, K.C.B., D.C.L., M.D., LL.D., F.R.S. 1840-1 *John Lindley, Ph.D., F.R.S 1842-8 *Thomas Bell, F.R.S 1844-5 *James Scott Bowerbank, LL.D., F.R.S ^ 1846-7 *George Busk, F.R.S 1848-9 * Arthur Farre, M.D., F.R.S 1850-1 ^George Jackson, M.R.C.S 1852-3 * William Benjamin Carpenter, C.B., M.D., LL.D., F.R.S. . 1854-5 George Shadbolt 1856-7 *Edwin Lankester, M.D., LL.D., F.R.S 1858-9 *John Thomas Quekett, F.R.S 1860 ^Robert James Farrants, F.R.C.S 1861-2 ^Charles Brooke, M.A., F.R.S 1863-4 James Glaisher, F.R.S 1865-6-7-8 *Rev. Joseph Bancroft Reade, M.A., F.R.S 1869-70 * William Kitchen Parker, F.R.S 1871-2 ^Charles Brooke, M.A., F.R.S 1873-4 Henry Clifton Sorby, LL.D., F.R S 1875-6-7 *Henry James Slack, F.G.S 1878 Lionel S. Beale, M.B., F.R.C.P., F.R.S 1879-80 *Peter Martin Duncan, M.B., F.R.S 1881-2-3 Rev. William Hy. Dallinger, M.A., LL.D., F.R.S. 1884-5-6-7 Charles Thos. Hudson, M.A., LL.D. (Cantab.), F.R.S. 1888-9-90 Robert Braithwaite, M.D., M.R.C.S., F.L.S 1891-2 Albert D. Michael, F.L.S 1893-4-5-6 * Deceased. COUNCIL. Elected 20th January, 1897. |)rcsibmt. Edward Milles Nelson, Esq. ^ .^itc-lpresibents. Robert Braitkwaite, Esq., M.D., M.R.C.S., F.L.S. Rev. Edmund Carr, M.A., F.R.Met.S. * Frank Crisp, Esq., LL.T3., B.A., Y.P. & Treas. L, ^Albert D. Michael, Esq., F.L.S. treasurer. William Thomas Suffolk, Esq. .Secretaries. Prof. F. Jeffrey Bell, M.A. Rev. W. H. Dallinger, LL.D., F.R.S. Ortmunm HI embers of Co illicit. C. Edmund Aikin, Esq., B.A., M.R.C.S. Conrad Beck, Esq. Alfred W. Bennett, Esq., M.A., B.Sc., F.L.S. Edward Dadswell, Esq. Richard G. Hebb, Esq., M.A., M.D., F.R.C.P. * George C. Karop, Esq., M.R.C.S. Prof. E. Ray Lankester, M.A., LL.D., F.R.S. The Hon. Sir Ford North. Thomas H. Powell, Esq. Charles F. Rousselet, Esq. John Jewell Yezey, Esq. Thomas Charters White, Esq., M.R.C.S., L.D.S. * Members of the Publication Committee. - CON T E N T S. TRANSACTIONS OF THE SOCIETY. PAGE I. A New Calculating Machine. By Edward M. Nelson, F.R.M.S. (Fig. 1) . . 1 II. On the Male of Rhinops vitrea. By Charles F. Rousselet, F.R.M.S. (Plate I.) 4 III. Second List of New Rotifers since 1889. By Charles F. Rousselet, F.R.M.S. 10 IV. Presidential Address : Suggestions as to Points connected with the Micro- scope and its Accessories still needing Improvement. Resume of the Anatomy of Bdella. By A. Michael, F.L.S., &c 97 V. On a New Mechanical Stage (Figs. 11-15. By Edward M. Nelson, President R.M.S 185 VI. On the Development and Structure of Dental Enamel. By J. Leon Williams, D.D.S., L.D.S., F.R.M.S. (Plates I r.-V.) 261 VII. The Limits of Species in the Diatomacese. By Thomas Comber, F.L.S., F.R.M.S 455 VIII. A Contribution to the Freshwater Algse of the South of England. By W. ' West, F.L.S., and G. S. West, A.R.C.S. Communicated by A. W. Bennett, F.L.S., F.R.M.S. With Appendix by A. W. Bennett, F.L.S., F.R.M.S. (Plates VI. and VII.) 467 SUMMARY OF CUBRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY (PRINCIPALLY INVERTEBRATA AND Cryptogamia), Microscopy, &c., including Original Communications from Fellows and Others.* 16, 107, 182, 188, 255, 269, 351, 512 ZOOLOGY. VERTEBRATA. a. Embryology. Heape, W. — Menstruation and Ovidation of Mcicacus rhesus 16 Floderus, Matts — Amitotic Nuclear Division in the Egg of the Hedgehog .. .. 17 Lange, J. — Oogenesis in the Mouse 17 Janosik, J. — Division of Ovarian Ova 17 Fischel, A. — Embryonic Variations and Growth 17 Tims, H. W. Marett — Tooth- Genesis in Canidse 18 Kukenthal, W. — Dentition of Manatee 18 Tiemann, H. — Development of Nostrils in Mammals 19 Meves, Fr. — Spermatogenesis in Salamander 19 Flemming, W. — Influence of Light on the Pigmentation of Salamander Larvae .. 19 Neal, H. V. — Segmentation of Nervous System in Squalus Acantliias 19 Schneider, G. — Genital Ducts of Teleosteans 20 Dean, Bashford — Larval Development of Amia calva 20 Kopsch, Fr. — Blastoderm Margin in Salmonidse 21 Sobotta, J. — Syncytium in Cleavage of Belone acus 21 * In order to make the Contents complete, the papers printed in the ‘ Transactions ’ and the notes printed in the ‘ Proceedings ’ are included here. nil CONTENTS. TACK Weismann, A. — Germinal Selection 107 Eimer, G. H. Th. — Evolution on Definite Lines 108 Beard, J. — Problems of Vertebrate Embryology .. 100 Houssay, F. — The Recapitulation Doctrine 109 Wilson, J. T., & J. P. Hill — Development of Teeth in Perameles 110 Assheton, R. — Experiments on Groivth of Blastoderm of Chick 110 Bauer, R. W. — Proportions of Yolk, Albumen , and Shell 1101 Mitsukuri, K. — Blastopore of Chelonia 119 Grassi, G. B., & K. Knaethe — Reproduction and Development of the Common Eel 111 M‘Lntosh, W. C. — Life- Histories of British Fishes Ill Heape, W. — Artificial Insemination 18S Lrusdew, W. S. — Artificial Fertilisation of Rabbit's Ova 188 Nussbaum, M. — Egg-laying in Rana fusca 189 Gemmil, J. F. — Oogenesis in Anura 189 Haiimar, J. A. — Development of Liver and Pancreas 189 Streiff, J. J. — Development of Thyroid Gland in Man .. 189 Bonnet, R. — Prochorion of the Dog 190 Strahl, H. — Placenta of Weasel 190 Hoffmann, C. K. — Development of Selachii 190 Poli, C. — Development of Auditory Vesicle in Vertebrates 191 Kathariner, L. — Fangs of the Adder j 192 Eblanger, R. yon — Attraction-Spheres in Spermatogenesis 192 Petersen, C. G. J., & G. B. Grassi— Life-History of the Eel 192 Emery, C. — Lines of Variation and Germinal Selection 193 Baldwin, J. Mark— Organic Selection 193 Bumpus, H. C. — Study in Variation 193 Schlater, G. — Problems of Heredity 19i Hill, L. — Experiments on Supposed Inheritance of Acquired Characters . . .. 194 Brandes, G. — Alleged Modification of Bird's Stomach 194 Flemming, W. — Influence of Heat and Light on Pigmentation of Salamander Larvae 195 Brandt, A. — Hypertrichosis 195 ■ „ Viragines .. . . ^ 195 Wilder, H. H. — Epidermis Folds on Palms and Soles of Primates 195 Hertwig, O. — Experimental Embryology 269 Fere, Ch. — Removal of Shell from Developing Ova 269 Hammar, J. A. — Protoplasmic Connections between Blastomeres 275 Montgomery, T. H., Jun. — Mesoderm and Body-Cavities 275 Rosenstadt, B. — Epitricliium of the Chick 279 Cunningham, J. T. — Recapitulation "51 Kochs, W. — Regeneration of Organs in Amphibia 352 Sobotta, J. — Maturation and Fertilisation in Amphioxus 353 Carnoy, J. B., & H. Lebrun — Germincd Vesicle and Polar Bodies in Batrachia .. 353 Cunningham, J. T. — Ovary and Ovarian Ova in Marine Fishes 353 Meves, F. — Development of Spermatozoa in Salamander 354 Sabatier, Armand — Spermatogenesis in Selachians 354 Loyez, M. — A Two-Headed Tadpole 355 Giglio-Tos, E. — Blood-Formation in the Lamprey 355 Andrews, R. R. — Development of Dental Enamel 355 Rex, H. — Mesoderm of the Anterior Region of the Head in the Duck 355 Price, G. C. — Development of Excretory Organs in Bdellostoma 355 Grassi, B., & S. Calandruccio — Further Researches on Metamorphosis of Murie- noids 356 „ „ ,, Development of Eels 356 Franz, K. — Development of Hypochorda and Ligamentum longitudinale ventrale in Telcostei 356 Klaatsch, H. — Morphological Nature of the Hypochorda 357 „ „ Gastrula of Amphioxus 357 Ruge, G. — Skeletal Cartilage of Outer Ear in Monotremcs 357 Brauer, A. — Development of Gymnophiona 357 Wolff, G. — Present Position of Darwinism 358 Davenport, C. B., & C. Bullard — Correlated Variation 359 Romanes (the late) Darwin , and after Danvin 512 Galton, Francis — Law of Heredity .. 514 CONTENTS. IX PAGE Bell, A. S. — Influence of a Previous Sire 514 Werner, F. — Regeneration of Tail in Lizards 514 Giard, A. — Hypotypic Regeneration 515 Ewart, J. Cossar — Critical Period in Development of Horse 515 Foot, K. — Origin of the Cleavage Centrosomes 515 Schultze, 0. — Directive Influence of Gravity on Development 516 Benedex, E. van — Historical Note as to Polar Bodies 516 Wilson, H. V., & J. E. Mattocks — Lateral Sensory Rudiment in Salmon .. . . 516 Hoffmann, 0. K. — Development of Selachii 516 H aswell, W. A. — Early Development of Cestracion 516 Nishikawa, T. — Passage of the Eye in a Flat-Fish 517 Ward, R. H. — Ovum in Testis of Lamprey 517 Brachet, A. — Liver and Pancreas in Ammoccetes 517 Hatta, S. — Development of Heart in Petromyzon 517 Ohlin, Axel — Development of Teeth in Bottle-nose Whale 518 Kopsch, Fr. — Double Gastrula in Lizard 518 0. Histolog-y. Kostanecki, K., & Siedlecki — Relation of Centrosomes to Cytoplasm 21 Ramon y Cajal, S. — Protoplasm of Nerve-Cells 22 Szymonowicz, L. — Nerve-Endings of Duck's Bill 22 Gunther — Inner Root-Sheatli and Papilla of the Hair 22 Fischel, A. — Pigment-Cells 22 Ramon y Cajal, S. — Phagocytosis by Blood-Plates 23 Plato, J. — Function of Interstitial Cells of Testis 23 Sacerdotti, C. — Regeneration of Mucus Epithelium of Intestinal Tract in Amphibia 23 Wilson, E. B. — The Cell in Development and Inheritance Ill Giglio-Tos, E. — Blood of Lamprey 112 Ruffini, A. — New Nerve-Sheath 112 Marchesini, R. — Centrosomes and Attraction-Spheres in Leucocytes of Newt .. .. 112 Scupin, H. — Minute Structure of Ganoid Scales J 112 Henneguy, L. F. — Text- Book on the Cell 196 Dahlgren, U. — Giant Ganglion-Cells in Spinal Cord of Flat-Fishes 196 Schaffer, K. — Structure of Cerebral Cortex and Function of Nerve- Cell Processes 196 Dahlgren, U. — Centrosome Artifact in Nerve-Cells 196 Bunker, F. S. — Sensory Organs of the Lateral Line 196 Giglio-Tos, E. — Red Blood-Corpuscles 197 Ranvier, L. — Behaviour of Leucocytes in Injured Cornea 197 Marchesini, R. — Muscle-Fibres ; 197 Andeer, J. J. — Peritoneal Ostioles 197 Vincent, Swale — Suprarenal Capsules 197 Verworn, M. — Relation between the Form and the Metabolism of the Cell .. .. 270 Bambeke, Ch. van — Cell-boundaries 270 Eisen, Gustav — Plasmocytes 271 Trambusti, A. — Distinction between Leucoblasts and Erythroblasts 271 Juschtschenco, A. J. — Sympathetic Ganglion-Cells 271 Demoor, J. — Plasticity of Cerebral Neurones 272 Maurer, F. — Blood-Vessels in Epithelium 360 Volf, Pierre — Uterine Mucosa of Bat during Gestation 360 Triefel, H. — Cell-Bridges in Unstriped Muscles 361 Holm, J. F. — Comparative Histology of the Liver 361 Traube-Mengarini, Margherita — Permeability of the Skin 361 Schaffer, J. — Structure and Development of Cartilage in Cyclostomes 362 Botezat, E. — Nerve-Endings in Tactile Hairs of Mammals 362 Reinke. Fr. — Structure of the Neuroglia of the White Matter of the Spinal Cord .. 363 Bisogni, C. — Lingual Glands of Vipers 363 Cuenot, L. — Nuclear Degeneration and Renewal 363 Rutherford, W. — Structure of Striped Muscular Fibre 518 Kolliker, A. von — Cells and'Energids 519 Schaffer, J. — Centrosomes in Ganglion and Cartilage Cells 519 Boveri, Th.— Conditions of Cell-Division 519 Rosenstadt, B. — Formation of Skin Pigment 519 X CONTENTS, TAGE Kapsammer, G. — Periostal Ossification 520 Gehuchten, A. van — Dorsal Cells of Spinal Medulla 520 Tomes, C. S .—Tubidar Enamel 521 Mayer, F. — Nervous System of Ammoccetes 521 Studnicka, F. K. — Intercellular Connections in Notochord Tissue 522 y, General. Kennel, J. — Sexual Dimorphism and Variation .. .. .. 23 Ortmann, A. E. — “ Bipolarity ” in Distribution of Marine Animals 24 M‘Intosh, W. C. — Contrasts in the Marine Fauna of Great Britain 24 Ward, H. B. — Biological Examination of Lake Michigan 25 Dubois, R. — Poisoning of Freshwater Animals by Hypochlorite of Lime .. .. .. 25 Ortmann, A. E. — Natural Selection and Separation .. 113 Meldola, R. — Specific Characters 113 Yerrill, A. E. — Nocturnal Protective Coloration , .. .. 113 Kukenthal, W. — Explorations in the Moluccas and in Borneo 113 Davenport, C. B. — Experimental Morphology 198 Sandeman, G. — Problems of Biology ,. .. 198 Semon, R. — Bionomics of Australasian Animals 198 Frenzel, ,T. — Plankton Pump 199 Fowler, G. Herbert — Plankton of Faeroe Channel 199 Hjort, J. — Variation of the Plankton 199 Watase, S. — Physical Basis of Animal Phosphorescence 199 Fuhrmann, Otto — Fauna of Alpine Lakes 2C0 Jaeger, G. — Problems of Nature 272 Pearson, K. — Chances of Death 272 Hyatt, A. — Ontogeny and Phytogeny 273 Yerrill, A. E. — Nocturnal Protective Coloration 274 Varigny, H. De — Air and Life 274 Gill, Th. — Some Questions of Nomenclature 274 Quinton, R. — Influence of the Gradual Cooling of the Globe on Evolution .. .. 275 Zacharias, H. C. E. — Evolution of Head-Scales in Boidae 275 Stahr, H. — Function of the Lateral Organs 275 Weber, M. — Freshwater Fauna of South Africa 275 Willey, A. — New Ampliioxus 275 Parker, W. N. — Comparative Anatomy of Vertebrates 364 Poulton, E. B. — Anticipation of Modern Views on Evolution 364 Thilenius, G. — So-called Accessory Parts of the Skeleton 364 Hewlett, R. T. — Venoms of Toad and Salamander 365 Mitsukuri, K. — Japanese Zoology 366 Murray, George — Natural History of the Sea 366 Morris, C. — Life in the Primeval Ocean .. .. 366 Brewster, E. T. — Measure of Variability 522 Sweet, G., & H. Adolphi — Variations in Spinal Nerves of Hyla 522 Kohlbrugge, J. H. F. — Muscular Variations in Primates 522 Cattaneo, G. — Inheritance of Acquired Characters in Camels 523 Scharff, R. F. — Origin of European Fauna 523 Sutherland, A. — Temperatures of Reptiles , Monotremes, and Marsupials ' .. 523 Lucas, A. H. S. — Distribution of Terrestrial and Freshwater Vertebrates in Victoria 524 Bedriaga’s, J. von, Monograph of European Amphibians 524 Hoernes, R. — Fauna of Baikal Lake 524 Bruhn-Fahr^ius, — Number of White Corpuscles 524 Tunicata. Borgert, A. — Distribution of Doliolum 25 Todaro, F. — Development of Anterior Portion of Sal pa • • H4 Hvitfeldt-Kaas, H., & others — Tunicata of Norwegian North- Atlantic Expedition 115 Roule, L., & M. Caullery — Tunicata of the ‘ Caudan ’ Expedition 115 Lefevre, G. — Budding in Ecteinascidia 366 Caullery, Maurice — Compound Larva of a Synascidian 367 Metcalf, M. M -Follicle- Cells in Salpa 367 CONTENTS, XI INVERTEBRATA. page Richard, J. — Freshwater Fauna of the Azores 26 Monticelli, F. S. — Adelotacta Zoologica 26 Scott, T. — Brook’s Collection from the West Coast of Scotland 116 Brandt, K. — Fauna of the Kaiser Wilhelm Canal 116 Gratacap, L. P. — Hard Parts of Invert ebrata 276 Call, R. E. — New Discoveries in the Mammoth Cave 276 Ortmann, A. E. — Distribution of Marine Organisms 276 Kramer, A. — Microfauna of Samoa 368 Mollusca. Smith, E. A. — Indian Deep-Sea Molluscs 26 Gilchrist, J. D. F. — Mode of Life of Lima Mans 26 Baker, F. C. — Pulsations of the Heart in Molluscs 276 Thiele, J. — Shin- Glands of Molluscs 368 Sarasin, P. & F. — Molluscan Fauna of Freshwater Lakes in Central Celebes.. .. 368 Willey, A. — Notes on Nautilus 525 a. Cephalopoda. Verrill, A. E. — Gigantic Ceplialopod 116 W illey, A. — Embryology of Nautilus 116 Willey, A. — Opposition of Nautilus 200 Willey, A. — Notes on Nautilus 277 Verrill, A. E. — The Florida Sea-Monster 277 Goodrich, E. S. — Indian Cephalopods 369 y. Gastropoda. Gemmill, J. F. — Hermaphroditism of Limpet 27 M‘Murrich, J. Playfair — Yolk- Lobe and Centrosome of Fulgur .. .. .. .. 117 Bergh, R. — The Genus Doriopsilla 117 Bouvier, E. L., & H. Fischer — Structure and Affinities of Pleurotomaria .. .. 277 Hecht, E. — Multiple Reno-Pericardial Canals in Elysia viridis ». 277 Ludwig, H. — New Gastropod in an Antarctic Holotliurian 369 Gilchrist, J. — Nervous System of Molluscs 369 MacFarland, F. M. — Phenomena of Fertilisation and Maturation in Gastropod Ova 369 Collinge, W. E. — Structure of Apera Burnupi 370 Car, L. — Movements of Freshwater Gasteropods 525 Lee, A. Bolles — Spermatogenesis of Snail 525 Wierzejski, A. — Mesoderm of Physa fontinalis 526 D’Ailly, Adolf — Terrestrial and Freshioater Molluscs of Kameroon 526 Thiele, J. — Two Australian Solenogastres 527 5. Lamellibranchiata. Carazzi. D. — Green Oysters again 27 Frenzel, J. — Dreissensia polymorpha 117 Drew, G. A. — Anatomy of Sphserium soleatum 117 Chatin, J. — Clasmatocytes in Lamellibranchs 278 Rice, E. L. — Classification of Lamellibranchs based on the Gills 278 Bernard, F. — -Embryonic Shell of Bivalves 279 Bernard, Felix — Hinge-Teeth in Lamellibranchs 370 Boyce, R., & Herd, W. A. — Green Leucotyosis in Oysters 527 Plate, L. — “ Septibranchial ” Bivalves 527 Simroth, H. — Plankton Lamellibranchs 527 Bernard, Felix — Lamellibranch with an Internal Shell 528 Nagel, W. A. — Siphonal Papillae of Cockle 528 Bryozoa, Harher, S. F. — Notes on Cyclostoma 118 Maitland, R. T. — Eschara lapidescens van Baster 118 Xii CONTENTS. Arthropoda. tag Holmgren, E. — Tegumentary Innervation in Arthropods 118 Jaworowski, A. — Appendages of Arthropods 279 a. Insect^. Urech, F. — Colour-Variation in the Vanessas 28 Froggatt, W. W. — Bag-Shelter of Larvae, of Australian Moths 28 Xambeu — Metamorphoses of Beetles 29 Kenyon, F. C.— Brain of the Bee 29 Campbell, Jas. — Wasps 29 Middleton, R. M. — Bemarhdble Use of Ants 30 Gilson, G. — Thoracic Glands in Larvae of Trichoptera 30 „ „ & J. Sadones — Larval Gills of Odonata 30 Ris, F. — Gizzards of Odonata 31 Br andes, G., & others — Parasitic Beetles 31 Stone, G. E. — Resemblance of an Insect-Larva to a Lichen-Fruit , .. 32 Ihering, H. yon — Social Wasps of Brazil 32 Ruser — Life-History of Larvae of (Estrus 32 Bordas, L. — Nervous System of Mecopodinae 33 Porritt, G. T. — Larvae of British Butterflies and Moths 118 Dyar, Harrison G. — Larvae of the Higher Bomhyces 119 Henseval, Maurice — Mandibular Glands of Cossus ligniperda 119 Meves, F. — Structure of Nuclei in Spinning Glands of Caterpillars 119 Heymons, R. — Abdominal Appendages 119 Beijerinck, M. W. — Cynips Calicis 119 Garbasso, A. — Coloration of Scales in Beetles 120 Menegaux, A., & Cochon, J. — Life-History of Dendr act onus micans 120 Verhoeff, C. — Abdomen of Scolytidse 120 Williams, J. L. — Bees Intoxicated with Honey 120 Berlese, A. — Italian Coccidae of Fruit-Trees 121 Henseval, Maurice — Buccal Glands of Larval Trichoptera 121 Plateau, F. — How Flowers attract Insects 121 Kellog, Y. L. — Mallopliaga from Land-Birds 122 Cuenot, L. — Means of Defence in Insects 200 Leon, N. — Labium of Hemiptera .. 201 Linden, Maria von — Evolution of Lepidoptera 201 Luciani & Lo Monaco— Growth of Silkworms 201 Alexandrini, G. — Unusual Case of M?jiasis 201 Pantel, J. — Larva of Thrixion Halidayanum 201 Nassonow, N. — Notes on Strepsiptera 201 Goddard, M. F. — Second Abdominal Segment in Libellulidae 202 Porritt, G. T., & others — Lorvae of British Lepidoptera •. 202 Hart, C. A. — Aquatic Insects of the Illinois River 279 Lallier, P. — Myasis of Alimentary Canal in Man 279 Heymons, R. — Viviparity in Ephemerids 279 Muraoka, H. — Luminosity of Glowivorms 280 Butler, A. G. — Seasonal Dimorphism in African Butterflies 280 Laboulbene — Zeuzera JEsculi 280 Kenyon, F. C. — Optic Lobes of Bee's Brain 280 Rostrup, S. — Danish Galls 280 Kellicott, D. S. — Odonate Nymph from a Hot Spring 280 Smith, J. B. — Mouth-Parts of Insects 280 Bordas, L. — Classification of Ortlioptera 281 Heymons, R. — Development of Apterygota 281 Cockerell, T. D. A. — Check-List of Coccidae 281 Morse, E. S.— Mosquito-Bite 281 Alcock, A. — Natural Repellent Effect of “ Warning Colours ” 282 Izquierdo, Y. — Ejection of Offensive Liquids by Insects 282 Mayer, A. G. — Colours of Lepidoptera 282 Czerwinski, K. — Notes on Termites 282 Johnson, W. G. — New Scale-Insects 283 Gkassi, B., & A. Sandias — Castes in Termites 970 CONTENTS. Xlll PAGE Grassi, B. — Embiidse 372 Heymons, R. — Development of Lepisma 372 Uxel, H. — Development of Campodea 373 Klapalek, Fr. — Gonads and External Genital Appendages of Plecoptera . . .. 374 Coggi, A. — Viviparity of an Ephemerid 374 Bordage, Edmond — Tetrameric Regeneration of the Tarsus in Phasmidae .. .. 374 Janet, Charles — Natural History of Ants 374 AVasmann, E. — Notes on Ants 375 Janet, Charles — Relations of Antennophorus and Radius 376 Reuter, E. — Palps of Butterflies 376 Hanks, H. G. — A Californian Book-Worm 376 Janet, Charles — Tendons and Muscles of Hymenopter a 376 „ „ Association of Mites and Ants 377 Latter, O. H. — Prothoracic Gland of Dicranura Vinula 377 Bordas, L. — Sympathetic System of Orthoptera 378 Escherich, K. — Function-Change in Moulting Hairs of Insects 378 Matsumara — The Pear-Borer 379 Bordage, Edmond — Autotomy in Phasmidse 528 Yerhoeff, C. — Life-History of Halictus 528 Meinert, Fr. — Mouth-Parts of Insects 529 Nagel, W. A. — Taste-Organ in Lepidoptera 529 Genthe, K. W. — Mouth-Parts of Microlepkloptera 529 Ficalbi, E. — Revision of European Culicidse 529 Enock, F. — Male of Prestwichia aquatica 529 Thomas, F. — Mimicry in Oak-galls .. 530 Tubeuf, C. y. — Larch-galls 530 Meves, F. — Centrosomes in Spermatocytes of Lepidoptera 530 Adensamer, Th. — New Dipterous Parasite 530 /3. Myriopoda. Yerhoeff, C. — Notes on Lysiopetalidx 33 Yeriioeff, C. — Investigations on Diplopoda 202 Nemec, B. — Ovum of Diplopoda 202 Brolemann, H. W. — A Mysterious Myriopod 379 Silvestri, Filippo— Oviparity of Scolopendra 379 Verhoeff, C. — Morphology and Classification of Diplopoda , 379 Verhoeff, C. — Rheno-Prussian Diplopoda 530 Nemec, B. — Bohemian Diplopoda 531 Pocock, R. I. — New Indo- and Austro-Malayan New Diplopoda 531 Brolemann, H. W. — Algerian IuUdse 531 5. Araehnida. Blanchard, R. — Dermatobia noxialis 33 Piersig, R. — Hydrachnida of Germany 122 Neri, F. — Structure of Gamasidae 122 Jourdan, S. — Pseudo-Larval Copulation of some Sarcoptulie 123 Trouessart, E. — Halacarina of the ‘ Caudan ’ Expedition 123 Caullery, M. — Pycnogonida of the 1 Caudan ’ Expedition 123 Cambridge, O. Pickard — New Spiders 202 Janet, Ch. — Epizoic Mite on an Ant 203 Bambeke, Ch. van — Oogenesis in Photcus 283 W ASM ANN, E. — Mites and Ants 283 Pereyaslawzewa, S. — Development of Phrynidse 379 Bernard, H. M. — Galeodidse 380 Soar, C. D. — Notes on Hydrachnidx 381 Pocock, R. I. — African Solifugae 531 Pereyaslawzewa, Sophie— Development of Pedipalpi 531 Thorell, T. — New Spiders from Southern Asia 532 Kcenike, F. — New Hydrachnids 532 Trouessart, E. L. — Wine-Mite 532 XIV CONTENTS. e. Crustacea. 1)AGE Rosenstadt, B. — Eyes of Decapods 33 Warren, E. — Variation in Portunus depurator 34. Thompson, H. — Changes in the Carapace of Carcinus Msenas 34. Rosenstadt, B. — Lucifer Reynaudi 35 Nemec, B. — Peripheral Nervous System 35 „ „ Visceral Nervous System of some Isopods 35 Roule, L. — Development of Asellus 35 Guerne, J. De, & J. Richard — Freshwater Copepoda and Cladocera of Portugal.. 36 Garstang, W. — Functions of certain Diagnostic Characters of Decapod Crustacea .. 123 Zonnier, J., & others — Crustacea of the 4 Caudan ’ Expedition 124 Zograf, N. de — Embryonic Nervous System of Crustacea 124 Rizzardi, N. — Enlomostraca of Lake Mezzola 124 Richard, J. — Revision of Cladocera 124 Garstang, W. — Notes on Crabs 203 Hansen, H. J. — Development and Species of Sergestes . . . 203 Man, J. G. de — Malayan Decapods and Stomatopocls 204 Walker, A. O. — Notes on Distribution of Amphipoda .. .. 204 Hjort, J. — Sarcotaces arcticus 204 Caullery, Maurice — New Epicarid Parasite 204 Giesbrecht, W., & others — Development of Monstrillidas 204 Thompson, I. C. — Free-Swimming Copepods from West Coast of Ireland . . . . 205 Carlton, E. P. — Brain and Optic Ganglion of Leptodora hyalina 205 Sars, G. O. — South African Entomostraca 205 Beecher, C. E. — Classification of Trilobites 205 Newbigin, M. I. — Pigments of Lobster 283 Parker, G. H. — Photomechanical Changes in Retinal Pigment-Cells of Pdlsemonetes 284 Ortmann, A. E. — Trapeziidx 285 Henderson, J. R. — Neio Paguridee 285 Weber, M. — Freshwater Crustacea of South Africa 285 Bars, G. O. — Mysidas of the Caspian 285 Nemec, B. — New Cave lsopod 285 Sars, G. O. — Ampliipods of the Caspian 285 Alcock, A. — New Species of Branchipus 286 Sharpe, R. W. — North American Freshwater Ostrcicods 286 Scourfield, D. J.' — Olfactory Setae of Cladocera 286 Ross, L. S. — Some Manitoba Cladocera 286 Topsent, E. — Pycnogonids 286 Butschinsky, P. — Segmentation of Nebalici Ovum 381 Dollfus, Adrien — New Subterranean Isopods 381 Y ire, Armand— Sense-Organs of Subterranean Crustaceans 382 Steuer, A. — Eye of Corycxus 382 Milne-Edwards, A., & E. L. Bouvier — The Genus Sympagurus 383 Giesbrecht, W. — Systematic Notes on Copepocls 383 Walker, A. O. — New Edriophthalma from Irish Seas 383 Wat an abe, H. — Phosphorescence of Cypridina Hilgendorfii 384 Brady, G. S. — New Ostracods 384 Nusbaum, J., & W. Schreiber — Peripheral Nervous System in Crayfish 532 Bohn, Georges — Respiration of the Crab * 533 Spencer, Baldwin, & T. S. Hall— New Terrestrial Isopod 533 Forbes, E. B. — North American Species of Cyclops 533 Matile, Paul — Copepods of Moscow 533 Schmeil, O. — Freshivater Copepods of Germany 534 Marsh, C. Dwight — Limnetic Crustacea of Green Lake 534 Annulata. Malaquin, A. — Epigamy and Schizogamy 36 Michel, A. — Combined Nucleoli 36 Kowalevsky, A. — Lymphatic Glands of Nereids 37 Benham, W. B. — Earthworms from Celebes 37 Roule, L. — Marine Annulata of the 4 Caudan ’ Expedition 125 Horst, R. — Polychasta of the Netherlands 125 CONTENTS. XV pagk Smith, F. — North American Oligochseta 125 Beddard, F. E. — Oligochseta of South America 125 Rosa, D. — Lymphocytes of Earthworms 125 Bolsius, H. — Unpaired Gland of Hxment aria 125 Kunstler, J., & A. Gruvel — “ Urns ” of Sipunculus 126 Haecker, Y. — Pelagic Larvae of Polychseta 206 Caullery, Maurice, & F. Mesnil — Asymmetry of Spirorhis 206 Smith, F. — New American Species of Megascolides 207 Wagner, F. yon — Regeneration of Fore-gut in Lumbriculus 207 Kowalevski, Al. — Species of Acanthohdella 207 Mead, A. D. — Ovum Centrosome in Chsetopterus 286 Hescheler, K. — Regeneration and, Autotomy in Earthworms 287 Smith, F. — New North American Oligochseta 287 Michaelsen, W. — New Oligochseta 287 Nusbaum, J., & Jan Rakowski — Heart-Body of Enchytrseidx 287 Hesse, R. — Eyes of Hirudinea 288 Goodrich, E. S. — Nephridia of Polychseta 384 Cantacuzene, J. — Phagocytic Organs in Marine Annelids 385 Schwely, A. — Structure and Development of Spirorhis borealis 385 Gilson, G. — Septal Valves of Owenia 386 Benham, W. B. — New Species of Perichseta 386 Michaelsen, W. — New Species of Earthworm 386 Aida, T. — Chsetognatha of Misaki 386 Goodrich, E. S. — Structure of Sternaspis 534 Ehlers, E. — East African Polychseta 534 Moore, J. Percy — Nephridium af Discodrilidx 534 Andrews, E. A. — Plasmic Processes emitted from Serpida Eggs 535 M‘Intosh, W. C. — Notes on Polychseta . . 535 Aida, T. — Growth of Ovum in Sagitta 535 Rotatoria. Rothert, W. — Notommata wernecki 41 Zograf, N. de — Locomotor Apparatus of Rotifers 126 Hempel, Adolph — New Species of Rotifers from the Illinois River 207 Kofoid, C. A. — Trochosphsera solstitialis 207 Kellicott, D. S. — Rotifera of Sandusky Bay 207 Collin, Anton — Rotatoria from East Africa 208 Scorikow, A. S. — Rotatoria of the Neighbourhood of Kharhow 208 Stokes, A. C. — Some new Forms of American Rotifera 288 Shephard, T. — Lacinularia elongata, a new Rotifer 288 Rousselet, C. F. — Brachionus hakeri and its Varieties 288 Dunlop, M. F. — Metopidia pterygoida , a new Rotifer 289 Scherren, Hy. — Rotifer Commensal with Caddis- Worm 387 Zacharias, O. — Mastigocerca hamata sp. n 387 Nematohelminthes. Henry, F. — Fflaria nocturna 37 Stossich, M. — The Genus Ascaris 126 Brandes, G. — Life-History of Ascaris lumbricoides 126 Graefe — Ascaris megalocepliala as Cause of Death 126 Colucci, V., & L. Arnone — Simondsia paradoxa in the Stomach of Wild Boars .. 127 Stossich, M. — Helminthological Notes 127 Geisse & others — Life-History of Trichina 208 Woodworth, W. McM. — Filaroides in Frontal Sinuses of Skunks 208 Linstow, v. — Classification of Nematoda 289 Nassonow, N. — Excretory System of Nematodes 289 Chatin, J.— Alleged Nematode-Parasites of Truffles 289 Linstow, v. — Molin' s Genus Globocephalus 289 Romer, F. — Classification of Gordiidx 290 Lataste, F. — Gordius and Mantis 290 Dad ay, E. v. — Freshwater Nematodes of Hungary 296 Chatin, Joannes — Epidermic Nuclei of Anguillulidie . . 387 XVI CONTENTS. PAGE Camerano, L. — New Classification of Gordiidse 387 Spengel, J. W. — Excretory Organs of Ascarids 388 Collett, O. — Nematode Parasite from Mantis 388 Shipley, A. E. — Excretory Cells of Ascaridae 535 Sabaschnikoff, M. — Chromatin deduction in Oogenesis of Ascaris 536 Yalentini, L. — Ascariasis 536 Platyh.elminth.es. Montgomery, T. H., Jun. — New Freshwater Nemertean 38 Woodworth, W. M‘M. — Turbellaria of the Michigan State Fish Commission .. 38 Sabussow, H Haplodiscus 38 Otto, R. — Anatomy and Histology of Amphistomidae 38 Stafford, J. — Aspidogaster conchicola 39 Paroni, C., & Y. Ariola — New Species of Bilharzia 39 Lutz, A. — Distoma Opisthobrias 39 Sonsino, P. — Distomum felinum .. .. 39 Magalhaes, P. S. de — Hymenolepis diminuta Rudolphi found in Man 40 Linstow, 0. vox — Twnia (Hymenolepis) nana v. Siebold and Taenia murina Duj. 40 Schroeder, A. E. vox — Cysticerci of Bothriocephalus latus 40 Ward, H. B. — New Human Tapeworm 41 Bavay, A. — Remarkable Pseudhelminth 41 Bohmig, L. — Excretory Organs and Blood- Vascular System of Tetrastemma graecense 127 Muhling, P. — Notes on Trematoda 127 Scagliosa, G. — Taenia Botrioplitis in the Intestine of the Fowl 128 Luhe, M. — Nervous System of Ligula in its Relations to the Arrangement of the Musculature 128 Willey, A. — Ctenoplana 128 Brown, A. — Fragmentation in Lineus gesserensis 208 Montgomery, T. H., Jun. — Connective-Tissues and Body-Cavities of Nemerteans . . 209 Klinckowstrom, A. vox — Maturation and Fertilisation in Prostheceraeus vittatus 210 Sabussow, H. — Male Organs of Stenostoma leucops 0. Schm 210 Jagerskiold, L. A. — New Ectoparasitic Triclad 210 Lebedinski, J. — Development of Nemerteans 290 Montgomery, T. II., Jun. — New Metanemerteans 291 „ Nephridia of Stichostemma 292 Villot, A. — Species of Opliryocotyle 292 Hausmann, L. — Trematodes of Freshwater Fishes 292 Diamare, V. — Eutozoic Tuberculous New Formations 293 Bensley, R. R. — Two Forms of Distomum cygnoides 293 Hesse, R. — Eyes of Turbellaria and other Flat Worms 293 Willey, A. — Remarkable new Planarian .. .. 293 Plehn, M. — Three new Poly clads 294 Jacobi, A. — Diploposthe laevis 388 Diamare, Y. — Gonads of Amabilia . . * 389 Rosseter, T. B. — Cysticercus venusta 389 „ „ Cysticercus of Taenia liophallus 389 Pintner, Th. — Studies on Tetrarhynchci 389 Bettendorf, II. — Muscidature and, Sensory Cells of Trematodes 390 Jander, R. — Epithelium of Triclads . . .. , 390 Francaviglia, M. C. — Helminthological Notes 536 Mrazek, A. — Cysticercoids of Freshwater Crustacea 536 Bott, A. — Budding Cysticercus from Mole 536 Takakura, U. — New Species of Malacobdella 537 Steel, T. — Neiv Land Planarians 537 Incertae Sedis. Mastermann, A. T. — Structure of Actinotrocha 42 Willey, A. — Ptycliodera 294 „ „ Ctenoplana 295 Masterman, A. T. — Structure of Actinotrocha 537 „ „ Structure of Cephalodiscus 53S Harmer, S. F. — New or Rare British Marine Polyzoa 539 CONTENTS. XVII Echinoderma. tage Uexkull, J. von — Function of Polian Vesicles in Sea-Urchin 42 Perrier, R. — Elasipoda of the 4 Travailleur * and 4 Talisman ’ 43 Herotjard, E. — Holothurians of the ‘ Princess Alice ’ 43 Goto, S. — Embryology of Starfish 129 Gregory, J. W. — Echinocystis and Palxodiscus 129 „ „ Affinities of Echinoth uriidse 130 Ostergren, Hj. — Holothuriidx of Norway 130 „ „ Synallactinx 130 Andrews, Gwendolen F. — Pseudopodia in Ecliinoderm Ova and Embryonic Cells 211 Gregory, J. W. — Palaeozoic Ophiuroids 211 Iwanzofp, N. — Muscle-Fibres of Holothurians 211 Perrier, E. — Asferoidea of the North Atlantic 296 Kohler, R. — Deep-Water Ophiuridae from Indian Ocean 296 Ostergren, Hj. — Use of the Anchors in Synapta 296 Dendy, A. — New Zealand Holothurians 297 Ludwig, H. — Brood Care in Holothurians 391 Mitsukuri, K. — Changes in Calcareous Deposits of Stichopus 391 Kirk, T. W. — New Zealand Echinoderms 391 Yoshiwara, S. — New Species of Asthenosoma 391 Koehler, R. — New Ecliinothurid 539 Schenk, S. L. — Abnormalities in Ecliinoid Ova after Fertilisation 539 Ludwig, H. — Mediterranean Asteroids 510 Coelentera. Jaderholm, Elof — Extra-European Hydrouls 43 Iwanzoff, N. — Stinging-Cells 131 Sollas, W. J — Coral Reef at Funafuti 131 Roule, L. — Coelentera of the 4 Caudan ’ Expedition 131 Grieg, J. A. — Funiculina and Kophobelemnon 132 Agassiz, A., & W. M*M. Woodworth — Variations in Eucope 132 Parker, G. H. — Diversity of Structure in Metridium 211 Schultze, L. S. — Classification of Antipatharia 297 Schenk, A., & Kukenthal — New Alcyonaria 298 Germanos, N. K. — Gorgonacea of Ternate 298 Kwietniewski, 0. R. — Actiniaria of Ternate 298 Ostrooumoff, A. — Craspedota 298 Cam pen hausen, B. v. — Rydroids of Ternate 298 Hickson, S. J. — Ampullae in Millepora 299 Collcutt, M. C. — Structure of Hydractinia 392 Lendenfeld, R. von — Stinging-Cells 392 Duerden, J. E. — Aliciidae 393 Browne, E. T. — Tubularia crocea in Plymouth Sound .. . 540 Schneider, K. C. — Taxonomy of Hydroids 540 Brundin, J. A. Z. — New Alcyonaria 540 Seitaro, Goto — New Family of Hydromedusae 540 Bernard, H. M. — Interrelationships of Madreporidae 541 Porifera. Minchin, E. A. — Natural Classification of Asconidx 43 Breitfuss, L. — Calcareous Sponges from Ternate 44 „ „ New Calcareous Sponge 44 Topsent, E. — Sponges of the 4 Caudan ’ Expedition 132 Dendy, A. — Non-Calcareous Sponges from Port Phillip Heads 132 Topsent, E. — Sponges of Amboina 211 Doderlein, L. — Lithonina 299 Minchin, E. A. — Position of Sponges in the Animal Kingdom 393 Ijima, J. — Hexactinellids with Discoctasters 393 Dendy, A. — Non- Calcareous Sponges of Victoria 541 Schulze, F. E. — Revision of Asconematidae and Rossellidx 541 b XV111 CONTENTS. Protozoa. tage Greenwood, M. — Nucleus of Protozoa 44 Kofoid, C. A. — Protozoa of Lake Michigan 45 Lindner, G. — Hygienic Importance of Parasitic Vorticellse 45 Leyden, E. v., & F. Schaudinn — New Amoeboid Rhizopod 45 Weisser & A. Maassen — Mtiology of Texas Fever 46 Sanfelice, Fr. — Sarcosporidia in Muscle-Fibres of the Tongue of Cattle and Sheep 46 Silvestri, A. — Foraminifera of the Adriatic 132 Rouget, J. — Trypanosomata of Mammalia 133 Labbe, A. — Monograph on Coccidia 212 Yerworn, M. — Physiology of the Cell 299 Meyer, Hs. — New Flagellata 299 Butschinsky, P. — Protozoa of Salt Lakes 300 Karawaiew, W. — New Radiolarian 300 Kimsky-Korsakow, M. — New Holotrichous Infusorian 300 Wallengren, Hs. — Species of Tricliodina 300 Labbe, A., & E. G. Racovitza — New Gregarine 300 Leger, L. — Coccidia of Myriopods 300 „ „ Life-Cycle of Coccidia 301 Yasuda, A. — Influence of Various Solutions upon Infusoria 394 Dallinger, W. H. — Biflagellata 394 Grassi, B., & A. Sandias — Parasitic Flagellata of Termites 394 Le Dantec, Felix — Regeneration of the Micronucleus in Ciliata 395 Leger, Louis — Experimental Study of Coccidia 395 Mesnel, F., & E. Marchoux — New Type of Sporozoa 395 Cuenot, L. — Gregarines of the Cricltet 396 „ „ Double Use of the Name Diplocystis 396 Simond, P. L. — Life-History of Coccidia 397 Leger, L. — New Myxosporidium 397 Penard, Eugene — A Swimming Heliozoon 541 Nussbaum, M. — Revivification of Infusoria 542 Thomas, F. — Euglenia sanguinea .. 542 Sterki, Y. — Stichospira paradoxa 542 Wasielewski, Yon — Guide to Sporozoa .. 542 Marchoux, E. — Malaria in Senegal 542 Grigorjew, A. — Nature of the Parasite of Rabies 543 Sasaki— Pebrine 543 BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-structure and Protoplasm. Degagny, C. — Respiratory Function of the Nucleus 47 Ztmmermann, A., & J. B. Farmer — Vegetable Cytology 47 Tswett, M. — Structure and Physiology of the Cell 134 Gerassimoff, J. J. — Non-Nucleated Cells 134 Kny, L. — Influence of Traction and Pressure on the direction of Partition- Walls .. 134 Lohmann, W. — Influence of Light on Cell-Division 213 Sargant, E. — Heterotype Divisions in Lilium Matagon 213 Buscaliont, L. — Formation of the Endosperm in Lreucojum 213 Pfeffer, W. — Influence of the Nucleus on the Formation of the Cell-Wall .. .. 302 Calkins, G. N. — Chromatin-reduction and Tetrad-formation in Pteridophyta .. 302 Molliard, M. — Cell-hypertrophies produced by Galls 302 Sargant, E. — Spermatogenesis in Lilium Martagon 398 Puriewitsch, K. — Honeycomb Structure of Vegetable Substances 398 Potter, H. B. — Streaming of Protoplasm in Pollen-Grains 399 CONTENTS. xix PAGE Green, J. Reynolds. — Cell-Membrane 399 Muller, C. — Inclusions in the Living Cell-icall 399 Townsend, C. O. — Influence of the Nucleus on the Formation of Cell-Wall .. .. 544 (2) Other Cell-contents (including Secretions). Etard, A. — Spectrum of Chlorophyll 48 Butschli, O., & A. Meyer — Artificial Starch 48 Keller, Ida A.— Colouring-Matter of the Aril of Celastrus 48 Green, J. R. — Reserve Food-Materials .. .. 48 Tschirch, A. — Formation of Secretions 134 Buscalioni, L. — Fncapsuling of Starch-Grains 135 Beijertnck, W. — Peculiarity of Soluble Starch 135 Couvreur, E. — Reserve- Stores of Seeds 135 Lewin, L. — Arrow-Poisons 135 Newbigin, M. J. — Pigments of Plants 214 Lutz, L. — Formation of Gum by Aralia spinosci 214 Ehring, C. — Colouring-Matter of the Tomato 214 Rywosch, S. — Oil in Leaves 303 Curtius, T., & J. Reinke — Volatile Reducing Substance in Green Cells 303 Gerber, C. — Tannins in Fruits 303 Lutz, L. — Production of Hydrocyanic Acid in the Pomex 303 Keeble, F. W. — Red Pigment of Flowering Plants 399 Rothert, W. — Structure of Starch-Grains 399 Guerin, P. — Soluble Starch 400 Jacquemin, G. — Aromatic Principles in Leaves 400 Chauliaguet, J., & others — Active Principles of the Aroidex 400 Biffen, R. PI. — Latex and its Function 400 Effront, J. — Caroubinase, a new Hydrolytic Enzyme 401 Etard, A. — Doubling of the Fundamental Rand of Chlorophyll 401 Macchiati, L. — “ Fncapsuling ” of Starch-Grains 544 Lotsy, J. R. — Localisation of the Alkaloids in Cinchona 544 (3) Structure of Tissues. Metzger, P. — Wood, of the Oak 48 Briquet, J. — Secreting Pockets of the Myoporcicex . . . . 48 Barth, F. — Structure of Trigoniacex and Chailletiacex 49 Rathay, E. — “ Gommose bacillaire ” of the Vine 49 Pieters, A. J. — Influence of Fruit-bearing on the Development of Mechanical Tissue 135 Gwynne-Vaughan, D. T. — Fibrovascular Bundles of Nymphxacex 136 Belli, S. — Endoderm and Pericycle in Trifolium 136 Worsdell, W. C. — Anatomy of the Stem of Macrozamia 136 Futterer, W. — Anatomy of the Zingiberacex 137 Brandis, D. — Structure of Dipterocarpacex 137 Drude, O. — Structure of Umbelliferx 137 Ramaley, F. — Anatomy of Onagracex 137 Boubier, A. M. — Anatomy of Betulacex 137 Czapek, F. — Leptome of Angiosperms 303 Tittmann, H. — Formation of Periderm and Epiderm 304 Matteucci, E. — Cork- Growths 304 Paratore, E. — Supernumerary Vascular Bundle in a Root 304 Kuster, E. — Anatomy of Chrysobalanex 304 Grevel, W. — Structure of Diapensacex 305 Jumelle, H. — Anatomy of Cissus gongylodes 305 Ahlfvengren, F. E. — Stem of Compositx 401 Cornu, M. — Stem of Cuscuta 401 Candolle, A. de — Structure of P iperacex 402 Vaughan, D. T. Gwynne — Polystely in Primula 402 Weisse, A. — Lenticels of Monocotyledons 402 Schoennett, M. — Resinocysts 402 Anderson, A. P. — Abnormal Formation of Resin-Ducts 403 Parmentier, P. — Anatomy of the (Enotherex and Haloragex 403 Rothert, W. — Membranes of Vessels 544 b 2 XX CONTENTS. I’AGE W orsdell, W. C. — Transfusion Tissue 545 Kuhla, F. — Origin and Distribution of Plielloderm 545 Schubert, B. — Parency Time- Sheath in the Leaves of Dicotyledons 545- Grelot, P. — Staminal Vascular Bundles 516 Cormack, B. G. — Polystelic Boots of Palms 546 Burgerstein, A. — Wood of Pomex and Amygdalese 546. Wieler, A. — Stem of the Sugar-Cane 546" Dangeard, P. A., & L. Armand — Changes produced by My corhiza in the Cells of the Host-Plant 547 Wier, A. — “ Sereli” -Disease of the Sugar-Cane 547 (4) Structure of Organs. Parmentier, P. — Importance of Anatomiccd Characters in Classification .. .. 49’ Bailey, L. VL.— Flower of Canna . 40 Rowlee, W. W. — Stigma and Pollen of Arisxma . . . . 49 Bessey, C. E. — Compound Ovaries 50 Girard, A. — Fruit of Phoenix melanocarpa 50 Ciiatin, A. — Symmetry of the Axis 50 Rothdauscher, H. — Stem and Leaf of Phyllanthex 50 Migliorato, E. — Spines of the Aurantiacex 50 Day, R. N. — Position of Leaves 50 IVIacDougal, D. T. — Beaction of Leaves to continuous Ba infall 51 Bossebceuf, F. — Petiole of Quercus 51 Keeble, F. W. — Anatomy of Loranthacex 138 Tieghem, P. van — Floral Leaves without Vascular Bundles 13S H aaoke, \V. — Variation in Flowers of Salix 138 Hansgirg, A. — Protection of Pollen from Bain 138 Robinsohn, I. — Twisting of Filaments 139 Ule, E. — Elongation of the Axis 1391 Grevillius — Xerophilous Plants 139 Jonsson, B. — Leaves of Xerophilous Plants 1S9> Schellenberg, H. C. — Structure and Function of Stomates 139 Meyer, G. — Tubers of the Artichoke 140 Goebel, K. — Young Form of Plants 214 Rimbach, A. — Geophilous Plant 215. Planchon, L. — Opening of the slower of (Enothera 215. Trail, J. W. H. — Deviations in the Flower of Polygonum 215 Fujii, K. — Flower and “ Nipples ” of Salisburia 215 Tieghem, P. van — Hairs on the Sepals of the Santalacex 216' „ Phanerogams with an Ovule destitute of Nucellus 216. Waiil, C. von — Winged Fruits and Seeds 21® Schniewind-Thies, J. — Septcd Nectaries r- .. 217 Bitter, G. — Leaves of Bcinunculacese and Umbelliferx 217 Arcangeli, G. — Leaves of Arum italicum 217 Molisoh, H. — Influence of the Soil on the Colour of Flowers 305 Clos, D. — Homology of the Anther 305 Gaucher, L. — Ovary of the Pomegranate 306 Worsdell, W. C. — Ovule of Christisonia 306 Macchiati, L. — Seeds of Papilionacese 306 Chatin, A. — Symmetry of the Appendicular Organs 306 Mattej, G. — Bed, Spots on Leaves 306 Went, F. A. F. C. — Dimorphic Branches of Castilloa 307 Baldrati, I. — Scales of the Bulbs of Allium 307 Keller, I. A. — Underground Bunners 307 Rimbach, A. — Contractile Boots of Arum 307 Thiselton-Dyer, W. T. — Evolution of the Cyclamen 307 Tieghem, P. van — Structure and Affinities of the Grubbiacex 308 Candolle, C. de — Vegetable Teratology 308 Rosen- — Belationship between the Structure and Function of Organs 403 Day, R. N. — Position of Dorsiventral Organs .. .. 403 Celakovsky, L. J. — Development of the Flower 403 Balazs, J. — Structure of Pollen- Grains 404 CONTENTS. XXI 1 AGE Wiegand, K. M. — Structure of the Fruit in Ranunculacex 404 Coufin, H. — Micropyle of the Seed in Leguminosx 404 -Robertson, C. — Crests of Seeds 405 Hamilton, A. C. — Domatia 405 Wachter, W. — Morphology of Aquatic Plants 405 Perrott, E. — Leaves of Aquatic Gentianacex 405 Hesselman, H. — Metamorphosed Buds of Lilium bulbiferum 406 Meehan, T. — Pellucid Dots in Hypericum 406 „ „ Honey-Glands in Plants 406 Goebel, K. — Glands of Tozzia and Lathrxa 406 Meehan, T. — Spines of the Aurantiacex 406 Sablon, Leclerc du — Tubers of Orchidese 406 Hartwich, C. — Tubers of Aconitum 407 Boiriyaut — Replacement of the Primary Root by a Secondary Root 407 Scott, D. H. — Spinous Roots 407 Muller, F. — Structure of Bromeliacex 407 Balicka-Iwanowska, G. — Morphology of Thelygonum Cynocrambe 407 Weisse, A. — Inflorescence of Compositx 547 Maly, G. W. — Cohesion and Chor'.sis of Foliar Leaves 547 Pampalont, L. — Underground Fruits 54S Gjokic, G. — Fruit and Seed of Viscum 548 Cornu, M. — Fruit of Argania Sideroxylon . . 548 Tieghem, P. van — Ovide and Seed of Hydnoracex 548 Merz, M. — Seeds of the Utriculariex 549 Marliere, H. — Seed of Ceratonia siliqua 549 Gregory, A. — Pericarp of the Ri^e 549 Reinke, J. — Assimilating Organs of Leguminosx 549 Arcangeli, G. — Spotted Leaves 550 Koorders, S. H., & H. Hallier — Hydathodes of Tropical Plants 550 Burrage, J. H. — Adhesive Discs of Ercilla 550 Warming, E. — Structure of Halophytes 551 Kramer, H., & V. B. Wittrock — Morphology of Viola 551 Rimpach, A. — Contractile Roots 551 Fron, G. — Root of Suxda and Salsola 552 Schrenck, H. v. — (Edema of Roots of Salix 552 B. Physiology. (1) Reproduction and Embryology. Tieghem, P. van — Embryology of Balanophoracex 51 D’Hubert, E. — Embryo-Sac of Succulent Plants 51 Coulter, J. M. — Significance of Chalazogamy 52 Day, D. F. — Parthenogenesis in Thalictrum 52 Hirase, S. — Fertilisation of Salisbu-ria 140 Ikeno, S. — Fertilisation of Cycas 140 Borzi, A., & others — Cross- Fertilisation and Self -Fertilisation 141 Familler, J. — Degradation and Transformation of Sexucd Organs 141 Hildebrand, F. — Influence of Nutrition on the Colour and Sex of Flowers .. .. 142 Ule, E. — Fertilisation of the Bromeliacex 218 Meunier, A. — Embryogeny of Veronica 308 Chamberlain, C. J. — Embryogeny of Salix 309 Coulter, J. M. — Embryogeny of Conifers 309 Hart, J. H. — Pollination by Bats 309 Burrill, J. H. — Fertilisation of Spring Flowers 309 Hansgirg, A. — Germination of Pollen- Grains 310 Moerius, M. — Reproduction 407 Schaffner, J. H. — Embryogeny of Sagittaria , 408 Meehan, T. — Cleistogamy in Umbelliferx 408 Muller, F. — Double Pollination .. •• 408 Hildebrand, F.— Pollination of Cyclamen 409 Robertson, C., & P. Knuth — Cross-Pollination and Self-Pollination 409 Coulter, J. M , and others — Embryogeny and Fertilisation in Lilia n 552 XXII CONTENTS. PAGE Koernicke, M. — Fertilisation and Embryogeny of Triticum 553 Webbek, H, J. — Antherozoids of Zamia 554 Ishikawa, C. — Development of Pollen-Grains of Allium 555 Schaffner, J. H. — Development of Sexual Cells in Typlia 555 Hegelmaier, F. — Polyembryony in Allium odorum 555 Movements of Fluids). Hartig, R. — Growth of Pines 52 MacDougal, D. T. — Relation of the Groivtli of Foliage Leaves and the Chlorophyll Function 52 Stutzer & others — Recent Literature relating to Leguminosse Tubercles and the Fixation of Free Oxygen 53 Naudin, C.— Physiology of the Root- Tubercles of the Leguminosse 53 Bouiliiac, R. — Fixation of Atmospheric Nitrogen by Algx and Bacteria .. .. 54 Copeland, E. P. — Influence of Light and Temperature on Turgor 54 Coupin, H. — Absorption and Emission of Water by Seeds 54 Muller, N. J. C. — Rontgen Rays and Vegetation 142 Thouvenin, 'hi.— Influence of Electricity on the Growth of Plants 142 Tolomei, G. — Influence of Electricity on Germination 142 Gruss, J. — Germination of Barley 142 Muller-Thurgau, E. — Influence of Nitrogen on the Formation of Roots 142 Macloskie, G. — Antidromy 143 Darwin, F., & others — Ascent of Water in Trees 143 Krober, E. — Transpiration 143 Bokorny, T. — Organic Nourishment of Green Plants 218 Stmeroff, K. — Influence of Light on the Growth of Plants 218 Laurent, E., & others — Assimilation of Ammoniaccd Nitrogen and Nitric Nitrogen 219 Krauss, G. — Function of Calcium oxalate 219 Day, T. C. — Germination of Barley 219 Riviere, G., & G. Bailbache — Influence of the Stock on the Graft 219 Ewart, A. J. — Vitality of Seeds 219 Candolle, C. de — Latent Life of Seeds 220 Huie, L. — Changes in the Tentacles of Droserci produced by Feeding 220 Pfeffer, W. — Temporary Suspension of the Action of Chlorophyll 220 Kohl, F. G. — Assimilating Energy of the Blue and Violet Rays of the Spectrum .. 310 Daniel, L. — Reciprocal Influence of Stock and Graft on one another 310 Vandervelde, A. J. J. — Influence of Chemical Reagents and of Light on Germina- tion 310 Burnett, K. C. — Influence of Light on Dorsiventrcil Organs 311 Ewart, A. J. — A ssimilatory Inhibition 311 Reiche, K. — Biology of Woody Plants 311 Lopriore, G. — Regeneration of Split Roots 311 Bubgerstein, A. — Transpiration of Tropical Plants 312 Montemartini, L. — Laics of Growth 409 Meehan, T. — Rhythmic Growth in Plants 410 Rimpach, A. — Growth of Allium ursinum 410 „ „ Growth of Colchicum autumnale 410 Goebel, K. — Germination of Cryptocoryne 411 Schneider, A. — Phenomena of Symbiosis 411 Dassonville, C. — Effect of Mineral Scdts on Development 411 Kinney, Asa S. — Effect of Electricity on Vegetation 412 Nilsson, N. H. — Influence of the Dark Heat-Rays on the Growth of Plants .. .. 556 Heinricher, E. — Germination of Parasitic Phanerogams .. 556 Daniel, L. — New Mode of Grafting 556 Davenport, C. B. — Role of Water in Growth 556 Giltay, E. — Transpiration in the Tropics 556 Tschermak, E. — Currents of Pigments and Saline Solutions in Dicotyledons .. 556 Nestler, A. — Excretion of Drops of Water from Leaves 557 Rowlee, W. W. — Mration of the Stem of Mikania 557 CONTENTS. XXlll (3) Irritability. page Newcombe, F. — Rlieotropism 54 MacDougal, D. T. — Transmission of Irritation in Sensitive Plants 143 Hart, J. H. — Irritability of Catasetum 144 Hansgirg, A. — Gamotropic and Carpotropic Movements of the Flowers of Grasses . . 144 ,, „ Phyllocarpy 144 Borzi, A. — Mechanism of the Phenomena of Sensitiveness 220 Oltmanns, F. — Positive and Negative PLeliotropism 221 Ewart, A. J. — Aerotropism of Roots 221 Jost, h. -Periodic Movements of the Leaves of Mimosa in the Dark 312 Bullot, G. — Growth and Curvature of Phycomyces 312 Kolkwitz, R. — Movements of Swarm-Spores, Antherozoids, and Plasmodes . . . . 412 Hansgirg, A. — Gamotropic and Carpotropic Movements 412 „ „ Ombrophoby of Flowers 412 Macdougal, D. T. — Curvature of Roots 413 Clifford, J. B. — Rlieotropism and Thermotropism in a Plasmode 413 Stahl, E. — Sleep of Plants 557 Schwendener, S. — Sensitive Cushions in Mimosa 558 (4) Chemical Changes (including Respiration and Fermentation). Lidforss, B. — Physiology and Biology of Winter-Green Plants 55 Hansteen, B. — Formation of Proteids from Asparagin 144 Gruss, J. — Formation and Dissolution of Hemicellulose 145 Richard^, H. M. — Respiration of Wounded Plants 145 Godlewski, E., & others — Nitrification 145 Kosutany, T. — Formation of Proteids in Plants 221 Sablon, Leolerc wdu — Formation of N on-nitrogenous Reserve-Substances in the Almond .. .. 221 Richards, H. M. — Evolution of Heat by Wounded Plants 221 Green, J. R. — Action of Light on Diastase 222 Brown, A. J. — Fermentative Power 222 Buchner, E. — Alcoholic Fermentation without Yeast 222 Lafar, F. — Technical Mycology 222 Pfeffer, W. — Formation of Diastase 312 Sablon, Leclerc du — Germination of the Almond 312 Emmerling, O. — Fermentation produced by Moulds 313 Gerber, G. — Influence of Temperature and Nutriment on the Respiration of Fungi 313 Gruss, J. — Action of Diastase on Reserve-Cellulose in Germination .. .. .. .. 414 Buchner, E. — Alcoholic Fermentation without Yeast-Cells 414 Deherain, P. P. — Reduction of Nitrates 414 Schulze, E. — Nitrates in Seedlings 415 Coupin, H. — Mucilage Excreted by Seeds 558 Gruss, J. — Secretion by the Scutellum 558 Cummins, H. A. — Function of Antitoxins 559 Buchner, E. — Advances in the Chemistry of Fermentation 559 Emmerling, O. — Butylalcohol Fermentation 559 yt General. Bessey, C. E. — Divergence of Monocotyledons and Dicotyledons .. 55 Wille, N. — Graft- Hybrid 55 Williamson, W. C., & D. H. Scott — Fossil Plants of the Coal-Measures .. .. 55 Tieghem, P. van — New Classification of Flowering Plants .. .. 313 Fry, Sir E. — Alternation of Generations 314 Schroter, C. — Plankton-Flora of the Swiss Lakes 314 Wiesner, J. — Mechanical Effect of Rain on Plants 560 Molisch, H. — Freezing of Plants 560 XXIV CONTENTS. B. CRYPTOGAMIA. Cryptogamia Vascularia. K Arnold, W. — Female Prothallium o f the Ileterosporous Lycopodiacex 55 Lang, W. H. — Sporanges on Prothallia 56 Lowe, E. J. — Division of the Prothallium of a Fern 56 Gibson, R. J. Harvey — Leaves of Selaginella 223 Lang, W. H. — Apogamous Reproduction in Ferns 223 Steinbrinck, C., & J. Schrodt — Opening of the Sporange of Ferns 223 Scott, D. H. — Cheirostrobus a new Type of Fossil Cone 314 David, E., & L. Weber — Anatomy of Lycopodium 415 Jeffrey, E. C. — Oophyte of Botrycliium 415 Osterhol’T, W. J. V. — Formation of the Karyolcinetic Spindle in Equisetum .. .. 416 Shaw, W. R. — Parthenogenesis in Marsilia 560 Behrens, J. — Regeneration of Selaginella 560 Charceae. Giesenhagen, K. — Bulbils of the Characese 147 Migula, W. — Rabenhont’s Cryptogamic Flora of Germany ( Characese ) 147 Debski, B. — Division of the Nucleus in Cliara 416 Giesenhagen, K. — Shoot-Nodes of Characese 416 Muscineae. Lorch, W. — Mucilaginous Paraphyses in a Moss 56 Brizi, U. — Rhynchostegium 146 Limpricht, K. G. — Rabenliorst's Cryptogamic Flora of Germany (JMusci) 146 Campbell, D. H. — Development of Geotliallus 146 Steinbrinck, C., & R. Kolkwitz — Swelling of the Peristome of Mosses 224 Bryhn, N. — Distribution of Spores in the Splachnaceae 224 Nyman, E. — ( Edipodium 224 Braithwaite’s British Moss-Flora 224 Barnes, C. R., & F. De F. Heald — Genera and Species of Mosses 224 Nawaschin, S. — Dissemination of the Spores in Sphagnum 225 Gayot, L. A. — Archegone of Muscinese 315 Bescherelle, E. — Ochrobryum 315 Howe, M. A. — Gyrothyra, a new Genus of Hepaticae 315 Solms-Laubach, H. Graf zu — Exormotheca 316 Muller, C. — Levierella , a neio Genus of Musci 416 „ „ Gemmae of Aulacomnium 417 Steinbrinck, C. — Hygroscopic Mechanism of the Peristome of Mosses 560 Familler, J. — Non-Sexual Propagation of Campylopus flexuot-us .. 561 Kamerling, Z. — Biology and Physiology of March antiacese 561 Algae. Bosse, A. Weber van — Sarcomenia 56 Gruber, E. — Fucaceas 57 Gomont, M. — New Genus of Freshwater Phaeosporeae 57 Went, F. A. F. C. — New Ceplialeuros 57 Bosse, Weber van — Pseudocod turn, a new Genus of Siphoncae 57 Rothert, W. — Rotifer Galls on Vaucheria 57 Klebs, G. — On Reproduction in Algae and Fungi 147 Tieghem, P. van — Verticillate Ramification 148 Agardh, A. G. — Analecta Algologica 148 Davis, B. M. — Procarp and Cystocarp of Ptilota 14S Wellheim, F. P. R. v. — Thorea 148 Tilden, Josephine E. — Pilinia and Stigeoclonium 148 Chodat, R. — Snow-Flora of Mont Blanc 149 Heydrich, F. — Corallinaceae 225 Brannon, M. A. — Structure and Development of Grinnelliu 225 Schmitz, F .—Gloiopeltis 226 CONTENTS. XXV PAGE Chodat, R. — Evolution of the Green Algx 226 Sauvageau, C. — Reproduction among the Plixosporex 226 Schmidle, W. — Epiphyllous Algx . 227 Nordstedt’s Index of Desmids 227 Gotz, H. — Characters of Vauclieria 227 Meyer, A. — Protoplasmic Communications in Volvox 228 Chmilewskij, W. — Structure and Multiplication of Pyrenoids in Algx 316 Sauvageau, C. — Antherids of Taonia 316 West, W. & G. S. — New African Genera of Freshwater Algx 316 Lommen, 0. P. — Conjugation of tivo Zygotes 317 Tilden, J. E. — Calcareous Algx 317 France, R. H. — Chlorogonium 317 Schmidle, W. — New Gongrosira 318 Moore, G. T. — Uroglena 318 Murray, G., & Y. H. Blackman — Coccospheres and Rhabdospheres 318 Chodat, R. — Encrusting and Perforating Algx 417 Eschle— Iodine in Algx 417 Foslie, M. — Melobesiacex 417 Oltmanns, F., & G. Berthold — Conjugation of Swarm-spores 418 Bokorny, T.- — Food-material of Algx and Fungi 562 Schmidle, W. — Arboreal Algx 562 Rothpletz, A. — Fossil Algx 562 Kuckuck, P. — New Marine Algx 562 Williams, J. Ll. — Antherozoids of Piety ota and Taonia 563 Schmidle, W. — Arrested Condition of Zygnema 563 Fungi. Wagner, G. — Distribution of Fungi by Snails 58 Bambeke, C. van — Membranaceous Mycele 58 Dangeard, P. A. — Chytridium simulans sp. n 58 Bresadola, J., & P. Hennings — New Genera of Fungi 58 Harper, R. A. — Behaviour of the Nucleus in the Development of the Fructification of the Ascomycetes 58 Dangeard, P. A. — Reproduction of Sphxrotheca Castagnei 59 Rabenhorst’s Cryptogamic Flora of Germany — Tuberacex 59 Neger — Fructification of Antennaria 59 Prillieux, E., & others — Parasitic Fungi 59 Buscalioni, L. — Saccliaromyces guttidatus Rob 60 Sappin-Trouffy — Fertilisation of the Ur edinex 60 Richards, H. M. — Development of JEcidia 60 Sappin-Trouffy — Parasites of the Uredinex 61 Ericksson, J. — Puccinia graminis 61 Sappin-Trouffy — Auricularia auriculx-Judx 61 Fox, T. C., & F. R. Blaxall — Ringworm Fungi 61 Meyer, A. — Protoplasmic Connection in Fungi 149 Wehmer, C. — Acid-loving Fungi 149 Goebel, K. — Dissemination of Spores by Rain 149 Schostakowitsch, W. — Mucor proliferus sp.n 149 Tanret, C. — Action of Nitrate of Ammonia on Aspergillus niger 149 Wehmer, C. — Rotting of Fruits 150 Underwood, L. M., & others — Parasitic Fungi 150 Went, F. A. F. C. — Sugar-Cane Diseases 150 Stoklasa, J. — Parasites of the Beet 151 Zoff, W. — Fungi Parasitic on Lichens 151 Horn, M. E. C. — Organs of Attachment of Botrytis 151 Nichols, M. A —Development of Teichospora and Ceratostoma 151 Laborde, J. — Eurotiopsis Gayoni 152 Shukow, J. — Consumption of Acids by Yeasts 152 Aderhold, R. — Fusicladium 152 Galloway, B. T. — Coleosporium Pint 152 Wagner, G. — Melampsora Tremulx 153 Roze, E. — Rhizoctonia 153 xxyi CONTENTS. PAGE Fischer, E. — Tuberacex, and Gasteromycetes 153 Burt, E. A. — Receptacle of Clatlirus 153 Gasperini, G. — Actinomycosis 153 Jona, G. — Protection of the Organism against Blastomycetes 154 Lendner, A. — Influence of Light and of the Substratum on the Development of Fungi 228 Zopf, W. — Parasymbiosis of Fungi 228 Chodat, R. — Effect of Low Temperatures on Mucor Mucedo 228 Matruchot, L. — Protoplasm of Mortierella 229 Dietel, P. — Characters of Ustilagineae . . . . 229 Marschall — Composition of the Mycele of Mould-Fungi 229 Sappin-Trouffy — Histology of the Uredinese 229 Woronin, M., & others — Parasitic Fungi .. 230 Viala, P., & A. Prunet — Blach-Rot of the Vine 230 Viala, P. — White-Rot of the Vine 231 Vuillemin, P., & P. Magnus — “ Leprosy ” of the Beet 231 Escombe, F.— Cell-membrane of Lichens 231 Jatta, A. — Minks’ s Lichen-Theory 231 Darbishire, O. V. — Roccellece 231 Eriksson, J. — Latent Life in the Uredineoe 232 Freudenreich, Ed.de — Kefir 232 Sanguinetti, J. — Amylomyces Rouxii and other Starch Ferments 232 Sanfelice, F. — Pathogenic Action of Blastomycetes 233 Steiner, M. — Pathogenesis of the Soar Fungus 233 Jennings, A. Y. — Mycorhiza of Corallorhiza 233 Janse, J. M. — Endophytic Mycorhiza 318 Thaxter, R. — Laboulbeniacese 319 Patouillard, N., & others — New Genera of Fungi 320 Tubeuf’s Parasitic Diseases of Plants 320 Ericksson, J. — Rusts of Corn 321 Boulanger, E. — New Conidial Form of Chsetomium 321 Aderhold, R. — Venturia and Fusicladium 321 Magnus, P. — Mycele of AEcidium magellanicum 321 Defendorf, A. R. — Relation of Yeasts to Malignant Tumours 321 Clements, F. — Origin of Lichens 322 Darbishire, O. Y. — Pertusariex, 322 Matruchot, L. — Structure of Agaricus (Pleurotus') ostreatus 322 Burnap, C. E. — Calostoma 322 Gilchrist, T. C., & W. R. Stokes — Presence of an Oidium in Pseudo-lupus vulgaris 322 Vuillemin, P. — Association of Chsetophoma oleacina and Bacillus Olese 323 Staub, M. — Fossil Fungi 323 Lesage, P. — Action of Alcohol on the Germination of the Spores of Fungi .. .. 418 Leger, M. — Mucorini 418 Schostakowitsch, W. — Mucor agglomeratus sp. n 419 Tepper, J. G. 0. — Entomogenous Fungi 419 Massee, G. — Geoglossese 419 Bucholtz, F. — Development of the Tuberacese 419 Aderhold, R. — Sclerotinia 420 McAlpine, D., & H. J. Webber— Sooty Mould of Citrus 420 Prillieux, E., & others — Parasitic Fungi 420 Minks, A. — Microgonids 420 Klocker, A., & H. Schionning — Origin of Saccliaromyces 421 Roncali, D. B. — Pathogenic Blastomycete found in Carcinoma 421 Wehmer, C. — Herring-Brine Yeast 421 Casagrandi, O. — Morphology of Blastomycetes 422 Ray, J., and others — Influence of Nutrient Media on the Development of Fungi . . 563 Johan-Olsen, O. — Pleomorphism of Fungi 564 Dangeard, P. A. — Classification of the Spores of Fungi 564 Hennings, P. — New Genera of Fungi 564 Hansen, E. C. — Fungi inhabiting Excrement 565 Zopf, W., & E. Kernstock — Fungi Parasitic on Lichens 565 Dangeard, P. A. — Red Pigment in Mucor 566 Thaxter, R. — Syncephalastrum and Syncephalis . . . . 566 CONTENTS. XXV11 PAGE Sappin-Trouffy — Systematic Position of Protomyces . . . . 566 Dangeard, P. A. — Sexual Reproduction in the Ascomycetes 566 Massif, G., and others — Parasitic Fungi 566 Ellis, W. G. P. — Fungus Parasitic on Pellia 567 Boulanger, E. — Development of Volutella 567 Bucholtz, F. — Meliola . . . . 567 Peglion, V. — Exohasidium Vitis 567 Zukal, H. — Morphology and Biology of Lichens 567 Burt, E. A. — Lengthening of the Receptacle of the Phalloideze 568 Simoni, A. de — Blastomycetes in Hypertrophied Tonsils 568 Myxomycetes. Dangeard, P. A. — Sappinia, a new Genus of Acrasieze. 62 Schilbersky, C. — Cribraria and Physarum 62 Zukal, IT,, & F. Ludwig — Myxobotrysaceze, a new Order of Myxomycetes .. .. 154 Roze, E. — Amylotrogus , a new Genus of Myxomycetes 154 Morgan, A. P. — Cytidium, a new Genus of Myxomycetes 155 Roze, E. — Vilmorinella, a new Genus of Myxomycetes .. 323 Zukal, H. — Myxobotrys 323 Roze, E. — Pseudocommis Vitis 422 ProtopRyta. a. Schizophyceee. Whipple, G. C. — Growth of Diatoms 62 Klebahn, H. — Formation of Auxospores in the Diatomaceze 62 Castracane, F. — Sporulation of Diatoms 63 Roze, E. — New Genera of Cyanopliyceze 63 Richter, P. — Nostocaceze 64 Gomont, M. — Hassallia and Tolypothrix 64 Murray, G. — Reproduction of Marine Diatoms 155 David, T. W. E. — Diatomaceous Earth 155 Zukal, H. — Structure of Cyanopliyceze and Bacteria 156 Chodat, R. — Oscillatoria rubescens 156 Karsten, G. — Auxospores of Diatoms 233 Lauterborn, R., & O. Muller — Structure , Division , and Movements of Diatoms 234 Van Heurck’s Synopsis of the Diatomaceze 235 Schmidt’s 1 Atlas der Diatomaceen-Kunde ’ 235 Zacharias, E. — Structure of Cyanopliyceze 235 Schmidle, W. — Development of Sphzerozyga 235 Castracane, F. — Rhizosolenia 323 Kolkwitz, R., & C. Correns — Movements of Oscillatoriaceze 324 Gran, H. H. — Protopliyta of the Norwegian Nordliavs Expedition, 1876-78 .. .. 422 Fischer, A. — Structure of Cyanophyceze and Schizomycetes 423 Gomont, M., & others — New Genera of Cyanopliyceze 423 Chodat, R. — Pelagic Flora of the Swiss Lakes 568 Kozlowski, W. M. — Movements of Diatoms 569 Migula, W. — Gallionella 569 Schmidle, W. — Resting-Spores in a Ccdothrix 569 B. Scliizomycetes. Copeman, S. M., & F. R. Blaxall — Action of Glycerin on the Growth of Bacteria 64 Pesina & Honl — Associated Action of Bacteria 64 Friedenthal, H. — Influence of the Induced Current on Bacteria 65 Klein, E. — Relation of Immunising Substances to Specific Microbes 65 Pammell, L. H. & E. — Gases produced by certain Bacteria 65 Klein, E. — Abilities of certain pathogenic Microbes to maintain their existence in icater 66 Freudenreich, E. von — Bacteriological Examination of Water for Coli Bacteria.. 66 Losener, W. — Pathogenic Bacteria in Buried Bodies . . 66 Sanfelice, F. — Epidemic among Pigeons caused by Bacillus coli communis . . . . 67 Nicolle, M. — Pigmentary Functions of Bacillus pyocyaneus 67 XXV111 CONTENTS. PAGE Delepine, S., & others — Agglutinative Action of Typlioid-Serum 67 Trumpp, J. — Diphtheria or Diphtheroid Bacilli in Empyema Pus 68 Wittlin, J. — Effect of Rbntgen Rays on Bacteria 156 Pfeffer, W. — Loose Combination of Oxygen in certain Bacteria 156 Renault, B. — Fossil Bacteria 157 Smith, E. F. — Bacterial Disease of Solanaceas 157 Peglion, V. — Bacteriosis of the Hemp ' 157 Drossbach, G. P. — Influence of the Cerium and Zirconium Groups on the Growth of Bacteria 157 Maze. — Fixation of Free Nitrogen by Bacilli of Root-Tubercles 158 Stutzer, A., & others. — Adaptability of Bacillus radicicola to Foreign Nutritive Media 158 Mecray, P. M., & J. J. Walsh — Bacteriology of Mumps 158 Calmette, A., & A. Delarde — Non-Microbic Toxins 159 Remlinger, P., & G. Schneider — Ubiquity of the Typhoid Fever Bacillus .. .. 159 ZENONr, C. — Homology of Streptococci 160 Nicolle, Cil, & A. Hebert — Tonsillitis caused by Friedlander's Bacillus .. .. 160 Grimbert, L. — Presence of Pneumobacillus of Friedldnder in Water 160 Pammel, L. H., & R. Combs — Micrococcus cyanogenus 161 Zeidler, A. — Termobacterium Aceti 161 Jennings, A. V. — New Genus of Schizomycetes with Longitudinal Fission .. .. 235 Beijerinck, W. — Emulsion and Sediment Figures produced by Motile Bacteria . . 236 Stutzer, A., & R. Hartleb— Nitre-Fungi 236 Burri, R., & A. Stutzer —Denitrifying Bacteria and the Loss of Nitrogen caused by them 236 Nobbe, F., & L. Hiltner — Inoculation of Nodule-Bacteria in different Host-Species 237 Smith, E. F. — Bacterial Diseases of Plants 237 Brizi, Ugo — Bacteriosis of Celery 237 Duggar, B. M. — Bacterial Disease of the Squash-Bug 237 Dobrzyniecki, A. R. y .—Leptothrix placoides 238 Rullmann — Cladothrix odorifera 238 Macchiati, L. — Silkworm Microbe 238 Krassilschtchik, M. — Rejuvenescence of Effete Pebrine Corpuscles 238 Goegg, G. — Bactericidal Action of Tannin 239 Bose & Delezenne — Mechanism of Immunity imparted by Anti- Coagulating Sub- stances 239 Kolle — Bacteriology of Plague 239 Janowski, W. — JEtiology of Dysentery 239 Pound, C. J. — Chicken-Cholera in Australia 240 Wickham, L. — Microbial Origin of Baldness 240 Martini, L. de — Differentiation of Diphtheria from Pseudo-Diphtheria Bacilli . . 240 Tictin, J. — Spirillum Obermeieri and Relapsing Fever Blood 240 Emmerling, O. — Bacillus forming Butyric Acid from Glycerol .. 241 Keferstein, G. — Pigment-forming Micrococcus from Red Milk 241 Schierbeck, N. P. — Influence of Carbonic Acid on the Growth of , and Toxin-for- mation by Diphtheria Bacilli 241 Vaughan, V. C., & G. D. Perkins — Pathogenic Bacillus found in Ice-Creams and Cheese 241 Leichmann, G. — Spontaneous Coagulation of Milk 242 Foulerton, A. G. R. — Agglutination Phenomenon in Glanders 242 Salimbeni, A. Taurelli — Agglutination Phenomenon and the Cholera Vibrio .. .. 242 Jones, A. C. — Biological Status of Bacillus Tuberculosis 242 Billings, J. S., & Adelaide W. Peckham — Influence of certain Yeasts in Destroy- ing the Vitality of the Typhoid and Colon Bacilli 243 Pakes, W. C. C. — Bacillus of Friedlaender in Tonsillitis and Pharyngitis .. .. 243 Lembke, W. — Bacterium coli anindolicum and Bacterium coli anaerogenes .. .. 243 Markusfeld, St. — Trichorrhexis nodosa 244 Paul, Th., & B. Kronig — Behaviour of Bacteria to Chemical Reagents 324 Charrin, A. — Plurality of Morbific Products from a single Pathogenic Microbe .. 325 Freudenreich, E. de — Microbic Agents of Cheese-Ripening 325 Branner, J. C. — Bacteria and the Decomposition of Rocks 326 Catterina, G. — Bacteria in Ice 326 Renault,!}. — Baderiacex of Bogheads 326 CONTENTS. XXIX PAGE Quest: & Landel — Evolution of Mucus in Cancer Cells 326 Abel, R., & W. M. Haffkine — Plague Bacillus 326 Dineur — Epidemic of Botulism 327 Forbes, S. A. — Bacteria normal to Digestive Organs of Hemiptera 327 Dyar, H. G. — Variation of Bacteria from Age 328 Dunham, E. K. — Bacillus capsulatus aerogenes 328 Dubois, L. — Action of Currents of High Frequency on the Virulence of Streptococci 328 Kedzior — Thermophilous Cladotlirix 328 Axenfeld, Th., & S. Stephenson — Bacteria of Conjunctivitis 329 Babes, V., & C. Levaditi — Actinomycotic Form of the Tubercle Bacillus .. .. 329 Widal, F., & A. Sicard — Serum Diagnosis with Agglutination Beaction in Typhoid Fever 329 Achard, Ch., & R. Bensaude — Presence of the Agglutinative Property in the Blood- Plasma and other Body-Juices « 329 Memmo, G. — YEtiology of Rabies 329 Cellt, A., & F. S. Santorini — Cattle Malaria 330 Lewkowicz, X. — Classification of Malaria Parasites 330 Sanarellt, G., & Havelburg — Microbes of Yellow Fever 330 Salmon, P. — Parasites of Vaccinia and Variola 331 Miyoshi, M. — Sulphur Bacteria of the Hot Springs of Yumoto 421 „ ,, Iron Bacteria in Hot Springs at Ihao 424 Ward, H. Marshall — Ginger-beer Plant 425 Stedman, J. M. — Bacterial Disease of Cotton , 425 Sormani, G. — Influence of the Rontgen Rays on Bacteria 425 Halban, J. — Resorption of Bacteria after Local Infection 425 Cotton, F. J. — Excretion of Bacteria by the Animal Body 426 Ward, H. M. — Pathogenic Water Bacteria 426 Facciola, L. — Micrococci of Malaria 426 Ogata, M. — Plague Bacillus 426 Hoff, H. J. van’t — Spirillum Maasei 427 Thomassen, W.—Septicsemia of Calves 427 Dobrzyniecki, Arpad R. v. — Two Cliromogenic Microbes from the Mouth .. .. 427 Ghadially — Micrococcus Ghadiallii 428 Malvoz, E. — Agglutination of Bacillus typhosus by Chemical Substances 428 Beauregard, H. — Bacteriology of Ambergris 428 Marie, A. — Fate of the Tetanus Toxin 429 Klein, E. — Staphylococcus lixmorrliagicus 429 Rullmann, W. — Nitroso- Bacterium with new Growth-Form 429 Flexner, S. — Pseudo-Tuberculosis Hominis Streptotricha 430 Keith, S. C. — Flavour-producing Micrococcus of Butter 439 Thaxter, R. — Myxobacteriacese 569 Ewart; A. J. — Evolution of Oxygen from Coloured Bacteria 569 Marpmann, G. — Ferrophilous Bacteria 570 Zinsser, O. — Root-Tubercle and other Bacteria in their Relation to Vegetable Tissue 570 Deyell, D. V. — Sensitiveness of Frogs to Infection with Plague 570 Fraser — Antivenomous and Antitoxic Qualities of the Bile of Serpents and of other Animals 570 Russell, H. L., & J. Wetnzirl — Rise and Fall of Bacteria in Cheddar Cheese .. 571 Migneco — Effect of Sunlight on the Virulence of Tubercle Bacilli 571 Bataillon and others — New Type of Tuberculosis 571 Schweinitz, E. A. de, & Dorset — Products of the Tuberculosis Bacillus .. . . 572 Bataillon & Terre — Saprophytic Form of Human and Avian Tuberculosis .. .. 572 Lohoff — Congenital Tuberculosis in the Calf 573 Auclair, J. — Human Tuberculosis in the Pigeon 573 Spiegel — Differential Diagnosis of Leprosy and Tubercle Bacilli 573 Unna — Fattiness of Lepra and Tubercle Bacilli 573 Sanfelice, F., and others — Barbone Disease of Cattle and Pigs 574 Smith, E. F. — Pseudomonas campestris ( Pammel ) 574 Loeffler & Frosch — Report of the German Commission on the Foot and Mouth Disease 574 Christmas, J. de — Gonotoxin 575 Ampola, G., & E. Garino — Bacillus denitrificans agilis and Denitrification .. .. 575 Babes, V., & G. Proca — YEtiology of Foot and Mouth Disease 575 XXX CONTENTS. PAGE Koplik, H. — Bacteriology of Pertussis 576 Glogner, M. — i Etiology of Beri-Beri 576 Sanarelli, J. — JEtiology of Yellow Fever 576 Nicolaysen, L. — Toxicity of Gonococcus 576 Nuttall, G. H. F. — Dissemination of Plague Bacilli by Insects 577 Hirsh, J. L., & E. Libman— Streptococcus of Enteritis 577 Binaghi, R. — Streptococcus capsulatus 577 Conn, H. W. — Story of Germ Life 577 MICROSCOPY. Text-Books of Histology 69 A. Instruments, Accessories, &c. (1) Stands. Stands and various Equipments 162 Stands and Optical Equipments 245 Nelson, E. M. — Evolution of the Microscope 332 Leiss, C. — Simple Microscope for Direct Observation and for Photography (Fig. 21) 332 Reichert’s Hand-Microscope (Fig. 22) 333 „ Stand and Illuminating Apparatus for Opaque Objects (Fig. 23) . . 333 Druner, L., & H. Braus — Preparation and Horizontal Binocular Microscope (Fig. 32) 431 Reichert, C. — New Stand (Fig. 33) 432 Cobb, N. A. — Method of Using the Microscope (Figs. 34-36) 433 Leiss, C. — New Stand, with Polariser and Large Illuminator (Fig. 44) 578 Nebelthau, E. — Stand for the Examination of Large Sections 579 12} Eye-pieces and Objectives. Stokes, A. C. — New Objective by Queen & Co 70 Rawlings, R. B. L. — Apertures of Objectives 162 (3) Illuminating: and other Apparatus. Tutton, A. E. — Monochromatic Light Apparatus 162 Leiss, C. — Lens-Support, with Polarising Apparatus (Fig. 8) 163 Karawaiew, W. — Thermostat heated by Mineral Oil for Paraffin Imbedding .. 163 Leiss, C. — Ocular-Dichroiscope (Fig. 16) .. ,. 245 Reichert’s Improved Illuminating Apparatus (Figs. 24-27) *. . 334 Rheinberg, J. — Coloured Illumination 336 Goodwin, W. — Portable Microscope Lamp (Fig. 28) 336 Jagger, T. A., Jun. — Simple Instrument for Inclining a Preparation in the Micro- scope 337 Schurmayer, B. — Modification of the Automatic Gas-Stop for extinguishing the Burner of Incubators . . 337 Robertson, S. — Slide and Cover-Glass Holders (Figs. 29 and 30) 337 Mohlenbruck, H. — Projection Lantern 438 Stokes, A. C. — Light-Filters and Colour-Screens 438 Smith, D. W. — Simple Machine for Micrometer Rulings (Fig. 37) 438 Brauns, R. — Covered Rectangular Motions for Stages (Figs. 38 and 39) 439 Reichert, C. — Lens-Support for Examining Seeds (Figs. 40 and 41) 440 Hesse, R. — Knife-Holder for Microtomes (Fig. 42) 441 Bolley, H. L. — Apparatus for Bacteriological Sampling of Well Waters (Fig. 45) 579 Meyer, A. — Bottle for Immersisn-Oil and for Canada Balsam (Fig. 46) .. .. 580 Reid, F. J. — Flash for Bacteria and High Tension (Fig. 47) .. .. 580 Ziegler, H. E. — Compressorium 581 Kantorowicz, R. — Heating Arrangement for Compressorium (Fig. 48) 581 Apathy, S. — New Knife-holder for Microtomes 582 Cheap Condensing Lens 582 CONTENTS. XXXI (4) Photomicrography. page Todd, G. B. — Use of Colour-Screens for Photomicrography 70 Giles, G. M. — On a Simple Method of Photomicrography by an inexpensive Apparatus (Figs. 9 and 10) 164 Eismond, J. — Photomicrographs 170 Gebhart, W. — A Simple Arrangement for talcing Slightly Enlarged Stereoscopic Photographs 170 Wright, A. E. — Method of Projecting a Micrometric Scale upon a Microscopic Specimen (Figs. 17-19) 245 Bray, T. J. — Photomicrography 338 Walmsley, W. H. — Acetylene Gas in Photomicrography 338 Mercer, A. C. — Astronomical Photography with Photomicrographic Apparatus . . 338 „ „ Photomicrograph v. Micropliotograph 339 Marktanner-Turneretscher, G. — Advances in Microphotography 339 Shearer, J. B. — Systematic Photomicrography (Fig. 43) 441 Golden, M. J. — Simple Apparatus for Photomicrography 582 (5) Microscopical Optics and Manipulation. Stoney, G. J. — Microscopic Vision (Figs. 2-6) 71 Marpmann, G. — Knife and Strop for Microtomes 247 Stokes, W. B. — Multiple Images in Mirrors 339 (6) Miscellaneous. Cori, C. J. — Diamond for Cutting Glass Discs 582 B. Technique. Cl) Collecting Objects, including Culture Processes. Kasparek, Th. — Simple Method for Excluding Air from Liquid Media used for Anaerobic Cultures 78 Capaldi, A. — Egg-yolk as an Adjunct to Nutritive Media 78 Edwards, A. M. — Growing-Cell 79 Fox, T. 0., & F. R. Blaxall — Cultivation Medium for Bingworm Fungi . . . . 79 Wroblewski, N. — Cultivating Pathogenic Schizomycetes on Media containing Supra- renal Extract 79 Richter, L. — Changes affecting Soil from Sterilisation 80 Wortmann, J. — New Stopper for Fermentation Flasks (Fig. 7) 80 Airol, a new Antiseptic 80 Practical Method for Preparing Agar for Cultivation Purposes 171 Uschinsky, N. — Cultivation of Diphtheria Bacilli on Non- Albuminous Media .. 171 Maurizio, A. — Culture of Saprolegnicicese 171 Schottelius, M. — Growth of Diphtheria Bacilli in Milk 171 Simmonds, W. — Keeping' Potatoes for Culture Purposes 171 Sawyer — Examining Bectal Mucus for Tubercle Bacilli ,, 172 Pfuhl, E. — Simple Method for the Sero -Diagnosis of Enteric Fever 172 Jackson, D. D., & G. C. Whipple — Improvement in the Sedgwick-Bafter Method for the Microscopical Examinaiion of Drinking Water 172 Klebs — Nutritive Medium for Algze 247 Sabouraud — Cultivating the Bacillus of Seborrlicea 248 Lustig. A., & G. Galeotti — Preparing Plague-Serum 248 Smirnow — New Method of obtaining Diphtheria Antitoxin 248 Delefine, A. S. — Technique of Serum Diagnosis 248 Ewell, E. E. — Apparatus and Method of Manipulation for the Preparation of Boll Cultures of Anaerobic Organisms (Fig. 31) Reed, R. C. — Preparation of Culture Media and their Sterilisation 311 London, E. S. — Bapid and Easy Method for Preparing Nutrient Agar 341 Schionning, H. — Apparatus for Cultivating Yeasts on Plaster Blocks 342 Casagrandi, O., & P. Barbagallo — Amoeba Culturesaeg 342 Tischutkin, N. — Culture Medium for Alee and Amoeb 313 Dorset, M. — Crystal Formation in Cluture Media 343 Frenzel, J., & V. IIensen— Plankton-Methods XXX11 CONTENTS. PAGE Kashida, K. — Medium for Differentiating the Bacillus typhosus from Bacterium coli commune 442 Christmas, J. de, & F. R. Hayner — Cultivating Gonococcus 443 Schardinger. F. — Protozoa Culture 444 Cori, C. J. — Closing Fishing Net (Fig. 49) 582 „ „ Mud Collector (Figs. 50 and 51) 584 Frosch, P. — Cultivation of Amoeba 584 Marpmann, G. — Silk-Glue as a Medium for the Cultivation of Bacteria 584 Michel, G. — Growth of Diphtheria Bacilli on Different Media .. .. .. .. 585 Steinschneider — Egg-yolk Agar for Cultivating Gonococcus 586 ( 2 ) Preparing- Objects. Kenyon, F. C. — Study of the Brain of the Bee 80 Aievole, E. — Method for Demonstrating Blastomycetes in Neoplasms 81 Arnold, J. — New Method for Examination of Blood 81 Meyer, Semi — Connections of Neurones 81 Gebhardt, W. — Isolation of the Elements of the Crystalline Lens 173 Zograf, N. de — Method of Preparing Rotifers 173 Brizi, TJ. — Preparing and Staining Celery for Demonstrating Bacteria 249 Zacharias, E. — Microchemical Methods for Examining Cells 249 Wright, A. E., & D. Semple — Employment of Dead Bacteria in the Serum Diagnosis of Typhoid and Malta Fever 250 Meyer, A. — Methods for Demonstrating the Continuity of Protoplasm 343 Cullen, T. S. — Rapid Method of making Permanent Specimens from Frozen Sections by the TJse of Formalin 344 Kischensky, D. — Method for rapidly Examining for Bacteria in cover-glass pre- parations 444 Osterhout, W. J. V., & Debski, B. — Observing Nuclear Division in Equisetum and Char a 445 Sargant, E. — Fixing, Imbedding, and Staining for Nuclear Division in Pollen- Grains 445 Hesse, F. — Agar as Medium for Bacteriological Examination of Water 446 Wasielewski, y. — Fixation and Staining of Cytoryctes vaccinre 447 Melnikoff-Raswedenkoff, N. — Method of Preparing Anatomical Specimens .. 586 Marpmann — Preparation and Use of Klein's Fluid for Separating Minerals and Diatoms 586 Ivopsch, F. — Modification of Golgi's Method 587 Schaper’s Reconstruction Method 587 Zograf, N. de — Method of Preparing Rotifers 588 Gordon, M. — Demonstrating presence of Flagella of the Plague Bacillus .. .. 588 Rousseau, E. — Decalcifying and Desilicating Sponges 588 (3) Cutting, including Imbedding and Microtomes. VVortmann, J. — Gelatin Method for Imbedding Objects for Exhibition 82 Schaffer, J. — New Microtomes by Fromme 173' Aubertin, G. — Manipulation of Celloidin Sections 174 Hyatt, J. D. — Cutting and Mounting of Sections of Cereal Grains 250 Flatters, A. — Simple Microtome for Biological Work 344 Rawitz, JB. — Proper Angle of Microtome Knife 447 Tandler, J. — Technique of Celloidin Serial Sections 447 Dollken, A. — Imbedding of Tissues ivithout hardening in Alcohol 448 Gebhardt, W. — Straightening of Paraffin Sections 449 Erbe, C. — Improved Cathcart Microtome (Fig. 52) 589 „ „ Weigert's Microtome 590 „ „ Microtome with Metzner's Double Support Guidance (Fig. 53) .. .. 590 (4) Staining and Injecting. Morrill, A. D. — Methylen-Blue 82 Bethe, A. — Methylen-Blue Methods 82 List, Th. — Differentiating Nucleolar Structures 83- Szymonowicz, L. — Nerve-endings of Duck's Bill 83 CONTENTS. XXX1U TAGE Pollack, B. — Weigert's Neuroglia Method 83 Bergh, Dr. H. van den — Staining Gonococcus by Gram's Method 84 Ernst, P. — Gram's Method St Knaak — Method for Contrasting Staining in Bacteriological Work 84 Marpmann — Staining Anthrax Cells in Blood 84 Hofmeister, J. — Sterilising of Syringes by Boiling . . 84 Catois — Investigation of Brain of Fishes 174 Zograf, N. de — Preparation of Embryonic Nervous System of Crustacea 174 Gulland, G. L. — Rapid Method of Fixing and Staining Blood-Films . . 175 Robertson, W. F. — Modification of Heller's Method of Staining Medullated Nerve- Fibres 175 Abel, R. — Staining Coccidium oviforme 175 Gerassimoff, J. J. — Method for Staining Unnucleated Cells 175 Rondelli, A., & L. Busoalioni — New Method of Staining Tubercle Bacilli . . . . 175 Schiefferdecker, P. — Decoloration of Celloidin in Orcein Preparations . . . 176 Marchesini, R. — Staining Centrosomes 176 Hierocles, G. X. — Effect of certain Chemical and Physical Agents on the Staining of Sporous and Asporous Bacteria 250 Raoiborski, M. — New Hsematoxylin-Stain 251 McCrorie, D. — Flagella Staining . . . . 251 Claudius — Simple Method for Contrast-Staining Micro- Organisms 344 Ivelsey, F. D. — Staining Vegetable Sections 345 Manson, P. — Method of Staining the Malaria Flagellated Organism 345 Craig, C. F. — Staining Diphtheria Bacilli 345 Roloff — Combination of Weigert's Fibrin Method and the Tubercle Bacillus Stain 345 Semonowicz, W., & F. Marzinowsky — Special Procedure for Staining Bacteria on Films and in Sections 449 Triepel, H. — Orcein Staining 449 Mayer, P. — Picrocarmine 449 Honsell — Differential Staining of Tubercle and Smegma Bacilli 450 Ivanoff, N. A.— Staining of Microbes and Phagocytes 450 Makchoux, E. — Staining Hsematozoa, of Malaria 450 Bremer, L. — Staining Reaction of Diabetic Blood 451 Eisen, G. — Notes on Fixation , Alcohol Method , Stains , Ac. 590 Wermel, M. B. — Combined Method of Fixing and Staining Microscopic Preparations 591 Pfeiffer, H. — Double-Staining Vegetable Tissue 592 Graberg, J. L. — Triple Stain for Animal Tissues 592 Yastarinl-Oresi — Method of Staining Nervous Tissue for Microscopic Purposes . . 592 (5) Mounting:, including Slides, Preservative Fluids, &c. Schiefferdecker, P., & E. Schoebel — Marking Preparations 176 Milani, A. — To Prevent Freezing of Formol 341 Melnikow-Raswedenkow — Preservation of Pathological Preparations 451 Gravis, A. — Fixation of Celloidin Sections 451 (6) Miscellaneous. Marpmann — Adhesive Material for Labels on Glass 84 Cement for Porcelain 85 Wortmann, J. — btain for Laboratory Tables 85 Schaper, A. — Plate Modelling . . .. 176 Zetzsche, F. — Tests for Ligneous Tissue 177 Marpmann, G. — Demonstrating Presence of Agar 177 Schab, von — Disinfection of Books 178 Keutmann, L. — Demonstration of Small Quantities of Formaldehyd 178 Wright, A. E., & D. Semple — Method of extemporising a Blowpipe for making Sedimentation Tubes 25] Istvanffy, J. — Botanical Application of the Rontgen Rays .. 251 Palmer, T. C. — Demonstration of the Evolution of Oxygen by Diatoms (Fig. 20) .. 252 Schroeder van der Kolk, J. L. C. — Microchemical Reaction for Nitric Acid .. 253 Wilson, L. A. — Dead-Black Surface on Brass 253 Goebel, K., & M. Raciborski — Laboratory Notes 253 • Bausch & Lomb— Reversible Mailing Cases 253 c XXX1Y CONTENTS. £ Ml . 1'AfiK Hoff, H. J. van’t — Bapid and Improved Method for Counting Plate Colonies .. 346 Macleod, N. — Method for Examining Malarial Blood 34 C Johnston & Jamieson — Bacteriological Diagnosis of leprosy .. 346 Bange, R., & A. Teantenroth— Diagnosis of Smegma and Tubercle Bacilli .. .. 847 Widal & others — Notes on the Agglutination Phenomenon of Typhoid Serum . . 817 Wiesner, J. — Photometric Determination of Heliotropic Constants 847 Burchardt, E. — Bichromates and the Nucleus ... 452 Woodworth, W. McM. — Method of Graphic Reconstruction from Serial Sections 452 Iwanoff, W. A. — Penetrating Power of Formalin Vapour 453 Stanton, A. T. — Process for Soldering Aluminium in the Laboratory .. 453 Cunningham, K. M. — Brownian Movement 154 Ballowitz, E. — Demonstrating the Electric Organs of the Bay 502 Bujwid, O. — Concentration of Therapeutic Sera by Freezing ■ 503 Pastes and Cements for General Purposes 503 Mondil — Bronzing of Copper .. .. 503 Browning Iron or Steel it .. 504 PROCEEDINGS OF THE SOCIETY. Meeting, December 16, 1896 89 Annual Meeting, January 20, 1897 ' 89 Report of the Council for 1896 99 Treasurer’s Account for 1806 .. .. 99 Sleeting, February 17, 1897 • 1/9 „ March 17, 1897 I81 April 21, 1897 -. 254 „ Slay 19, 1897 259 June 16, 1897 848 October 20, 1897 595 „ November 17, 1897 Index of New Terms in Zoology and Botany General Index to Volume 603 ■ 605 JOUBNAL OF THE EOTAL MICROSCOPICAL SOCIETY. FEBRUARY 1897. TRANSACTIONS OF THE SOCIETY. I. — A New Calculating Machine. By Edwabd M. Nelson, F.R.M.S. (l?em? lbth December , 1896.) This calculating machine, which has been made by Messrs. Watson, was designed by Mr. Tamblyn- Watts, and as it possesses much interest I ask leave to bring it before the Society, for the particular calculation that is performed by it is specially important to optical workers, and hence also to microscopists. The equation which this instrument is designed to solve is 1 ■x it not only is the focus of two lenses in contact as well as the position of conjugate foci found, but also many other problems are determined. To solve then the equation by the ordinary method the reciprocals of two figures have to be looked up, these have to be added or subtracted from one another, and lastly the reciprocal of the answer must be found. Now all these several steps are performed at one time by this instrument, which consists, as you will observe, of two scales placed at right angles to one another. Each of them is divided into 100 similar divisions, and each division is sub- divided into 5 smaller divisions. Now as a half of one of these small divisions can be easily estimated, these scales may be read to three significant figures. The third scale bisects the right angle, and is divided into 50 equal parts, each of which is subdivided into 5 smaller ones. These divisions, however, are not the same as those on the other two scales; in fact this third scale is not essentially necessary, it is only inserted for convenience, as will be presently seen. In order to solve the equation by means of this instrument all that is required is to stretch a piece of cotton thread from the point where (a) (fig. 1) is indicated on A C to the point where ( b ) is indicated on BC; the answer is found at the point where the thread crosses I) C (see dotted line). The correctness of the result may be 1897 b - ± - ; this is of frequent occurrence in optical formulae, for by i 2 Transactions of the Society. demonstrated as follows. Let AC = a and BC = 6; from the point D, where the thread (dotted line) cuts the diagonal, draw D E and D F perpendicular to A C and B C respectively. Call A E, p; EC,?/; and B F, s. Fig. l. /I Because the ang’ie D C E is half a right angle, and D E C a right angle, therefore CDE is also half a right angle, and consequently equal to DCF. Therefore DE=EC=y and D E C F is a square. Because A B meets the two parallels D F, A C the angle B D F is equal to the angle D A E, consequently their tangents are equal, thus £=», and y p ?/ 2 s = — a = T^v\ Therefore 6 = V + s = y + y (p + y) V - 4- - = 1 I 2 = 1. a h p + y y{p + y) y In order to find then the sum of — f- - place a T-square against A C to find the point E, where the perpendicular D E from the point D meets A C ; then E C is the required answer. The scale on the diagonal line therefore is not required to obtain a solution, but it is obvious that the scale EC may be transferred to C D, then the answer can be read off directly at the point D without the use of the T-square. For as x=yx/ 2 it is only necessary to make the divisions on CD 2 times larger than those on A C or B C. For example, if the A New Calculating Machine. Bij Edward M. Nelson. 3 divisions on A C or B C were one inch apart those on CD would have to be 1 * 4142 inches apart. To solve — = - — T , whilst taking out (a) on A C as before take x a b ° w (b) out on D 0, instead of on B 0, and read the answer on B C. Let then if but if Examples. a — 2*1, and b = 6 ' 5; -=-+b a = 1-59; x a b 1 _ 1 x a 1 b9 x = 3-10. By having the diagonal line graduated much trouble and incon- venience is thereby saved. I am sure the thanks of all optical workers are due to Mr. Tamblyn-Watts for such a simple labour-saving machine. 4 Transactions of the Society. II. — On the Male of Rhinops vitrea. By Charles F. Bousselet, F.B.M.S. (Bead 1 Zth December , 1896.) Plate I. Although Ehrenberg actually figured two male rotifers in 1838 lie did not recognise them as such, but described them as new species, and for ten years after the publication of his great work the Botifera were all considered hermaphrodite. The male of Hydatina senta Ehrenberg named Enteroplea hydatina , and he noted particularly that this was the only rotifer of which he could with certainty say that it had no trace of mastax and jaws. His second male rotifer he named Notommata granularis ; it is the male of a Brachionus, probably pala. Ehrenberg found some B. pala and also Notommata ( Notops ) brachionus , carrying clusters of small eggs unlike the ordinary eggs, and out of these small eggs he saw his N. granularis emerge ; and he came to the extraordinary conclusion that N. granu- laris laid its eggs on the back of N. brachionus, Brachionus pala, and other species of Brachionus, which reminded him of the story of the cuckoo, and for a time these small eggs were called cuckoo’s eggs . All through his work Ehrenberg has described the contractile vesicle and lateral canals as the male organs of rotifers, and he was so convinced of the monoecious character of the class, that the idea of a separate male rotifer never for a moment entered his head. In 1851 Dr. J. Weisse had repeated all these observations, and in addition had discovered the new species Biglena gramdaris, whose eggs, as he thought, he found lying amongst those of Biglena catellina, and he also noted that B. granularis had no jaws. After- wards he came to the conclusion that Enteroplea hydatina, Notommata granularis, and Biglena granularis were not different species, but that they were imperfectly developed, as yet toothless, young (“ unvol- lendete, noch zahnlose Junge ”) of respectively Hydatina senta, Brachionus pala and urceolaris, and Biglena catellina. But before this date, in 1818, Mr. Brightwell had made the important discovery and recognised the first male rotifer in As- planchna brightwelli, and in 1850 Mr. Gosse had found the male of A. priodonta. Then, in 1854, Dr. Leydig discovered the male of Asplanchna sieboldi, and declared his opinion that Enteroplea hydatina , Notommata gramdaris, and Biglena granularis were the males of the species with which Weisse had already associated them, although he himself had had no opportunity of seeing these males. In 1855 Prof. Cohn confirmed Dr. Leydig and more fully figured and described the males of Hydatina senta and B. urceolaris, and in 1856 Mr. P. H. Gosse published his celebrated paper, ‘ On the Dioecious Character of the Botifera/ in wThich he figured and 5 On the Male of Rhinops vittrea. By G. F. Rousselei. described the males of Braehionus pala, rubens , amphieeros, baker i , angular is, dorcas , and mulleri , Sacculus viridis, Polyarthra platy- ptera and S 'ynchseta tremula, which fully established the dioecious character of the Rotifera. Of late years a large number of other male rotifers have been discovered, and quite lately (in April last) our Journal reproduced two fine drawings of the male of Stephanoceros eichhorni , the discovery of which is due to Mr. John Hood ; the total number of species of which the males have been recorded is now about 64, a few of which, however, are doubtful. The chief characteristics of all male rotifers so far described are : their diminutive size, and the total absence of a mouth, mastax, jaws, oesophagus, gastric glands, stomach, and intestine, the ovary being replaced by a large sperm-sac. In the male of Rhinops vitrea (plate I. fig3. 1 and 2) which it is my privilege now to describe, the conditions are altogether at variance with what have so far been considered the essential characters of male rotifers, and quite a new type of male is here found to exist. At an excursion organised by the Quekett Microscopical Club to Esher on the 2nd of May last, we came upon a small pond which was found to contain Rhinops vitrea in considerable numbers, and as usual I filled a bottle of strained water from this pond. Upon examination of this water at home in a trough I observed a small elongated rotifer of somewhat different shape swimming swiftly among the more bulky and slower female R. vitrea ; it attracted my attention and I thought it might possibly be the as yet unknown male of this species, espe- cially as it played round the females according to the most approved fashion in Rotiferland, and a number of females had large spiny resting eggs, known to be the result of fertilisation, in their body-cavity. I therefore isolated a few specimens in a compressor for examination with a high power, and soon discovered that it was not only a male, but a male possessing fully developed jaws and functional digestive organs. The internal organs differed in no way from those of the female, except that the ovary on the ventral side was replaced by a rounded sperm-sac, in which the spermatozoa could be seen wriggling, prolonged into the usual copulatory organ. It was next necessary to demonstrate that this was really the male of Rhinops, so I isolated two stout females, the young in this species being always developed in the uterus within the body and brought forth alive, as in Asplanchna, and after a few hours I found several of the same males swimming about with the two females. I also isolated some other females so as to get some quite young females to compare as to size and shape with the males, and from these I found that the newly born females are considerably larger in bulk than the males, and that they resemble absolutely the adult females in shape, though somewhat smaller in size ; moreover, the ovary with bright germ-cells is seen very distinctly in the young female. As will be seen by the accompanying figures, for which I 6 Transactions of the Society . am indebted to my friend, Mr. F. E. Dixon-Nuttall, and also by the mounted slide under the Microscope in the room, the shape of the male of Bhinops vitrea differs somewhat from that of the female ; the body becomes suddenly narrower in the lumbar region, whilst in the female it tapers very gradually down to the toes. The body is very lithe and soft, bending constantly in every direction. The corona with its proboscis-like dorsal projection resembles that of the female in every way, and two red eyes are in the same manner situated near the extremity of the proboscis, each having a minute spherical crystalline lens imbedded in the red pigment. A dorsal antenna is seen on the dorsal side, a little below the eyes (this antenna is also present in the female), and the two lateral antennae are very conspicuous at the projecting angle of the lumbar region, each furnished with a brush of abnormally long setae ; in the female the lateral antennae are very small. The foot is short, consisting apparently of one joint containing the two foot-glands, and terminating in two minute toes. The chief characteristic and the most abnormal feature about this male is the possession of functional jaws and intestine. The jaws are like those of the female in structure, but in one specimen I thought the right malleus shorter than its companion on the left side. The oesophagus is a thin, narrow tube leading to an elongated thick-walled stomach, with two gastric glands attached, and continued behind into a narrow intestine, all ciliated in the interior. The jaws were frequently moving, but the contents of stomach and intestine were very slight and of a greenish tinge, without solid particles of large size. It seems clear, however, that the male of Bhinops can take in some food, and therefore sustain life and live longer than all other known male rotifers. No trace of an ovary could be found, but in its place, ventral to the intestine, is a rounded sperm-sac, at the lower end of which the spermatozoa could be plainly seen in motion, terminating in a duct with the usual retractile and ciliated copulatory organ. A small contractile vesicle and lateral canals with flame-cells attached are present as usual. In swimming the movements of these males were very lively, turning, bending, and twisting continually, and contrasting markedly with the slower gliding motion of the females. In size the males are 1/135-1/120 in. (0*188-0 *212 mm.), or a little over half the size of the females, and much more slender, on account of the narrower posterior part of the body. The discovery of this male opens up interesting questions as to the evolution of the male rotifers, which in the great majority of cases are little more than perambulating bags of spermatozoa, living a very short and merry life. The most rudimentary male I have yet seen is that of Polyarthra platyptera, which can hardly be distinguished from a Vorticella which has become detached from its stalk. It seems evident, however, that the males are simply degenerated forms, though why degeneration should have occurred at all must still remain 7 On the Male of Rhinops vitrea. By G. F. Rousselet. a mystery; in some species degeneration lias been carried further than in others, whilst in Rhinops vitrea it seems to have yet scarcely begun. In a large number of families the males are now known ; the Philodinidae, however, form a conspicuous exception, as no single male of the genera Philodina , Rotifer , Gallidina , or Adineta has yet been discovered. It has been proved by M. Maupas that the so-called winter eggs (which occur at all seasons) are those which have been fertilised by males ; both Dr. Janson and Mr. D. Bryce have observed spiny resting eggs in several species of Gallidina, and it is therefore not too much to infer that male Gallidina must exist. May it not be possible that the males in this family have jaws like the females, and have been overlooked, because the moment a Philodine was seen to have jaws it has been dismissed as an impossible male ? I would suggest to those who have made this family their special study to look for males, with sperm-sac instead of ovary, amongst Philodine3 showing fully developed jaws and digestive tract. I conclude this paper with a list of all Rotifers, 64 in number, whose males are known, with the names of the authors who have figured and described them : — Stephanoceros eichhorni Western, Dixon-Nuttall. Floscularia campanulata Hudson, Weber. „ mutabilis Hudson. „ calva Hudson. „ ambigua Hudson. „ coronetta Hudson. „ gossei Hood. „ pelagica Rousselet. „ cucullata Hood. Apsilus lentiformis Metschnikoff. Melicerta ringens Hudson. „ conifera Gosse. „ tubicolaria Hudson. „ janus Hudson. Limnias ceratophylli Gosse. I Fcistes mucicola Western. Lacinularia socialis Hudson. „ natans Western. Megalotrocha alboflavicans Anderson. „ semibullata Thorpe. „ procera Thorpe. Trochosphsera seguatorialis Thorpe. Gonochilus volvox Cohn, Hudson. „ unicornis Rousselet. Asplanchna briglitwelli Brightwell, Dalrymp^. „ priodonta Gosse. 8 Transactions of the Society. Asplanchna sieboldi Leydig, Daday. „ ebbesborni Hudson. „ intermedia Hudson. „ amphora Western. „ triophthalma Daday. Asplanclmopus myrmeleo Western. Ascomorpha ( Saccidus ) viridis Gosse. Microcodon claims Gosse. Synchseta tremula Gosse. „ gyrina Hood. Polyarthra platyptera Gosse, Plate. Triarthra breviseta ( = T. cornuta ) Plate. Bhinops vitrea Eousselet. Uydatina senta Hudson, Weber. Cyrtonia tuba Eousselet. Notops brachionus Hudson. „ clavidatus Western. Triphylus lacustris Western. C opens pachyurus Dixon-Nuttall. Proales parasita ( = Hertwigia volvocicola ) Plate. Diglena catellina Weisse, Weber. „ mustela Milne. Seison Grubii Claus. Paraseison asplanchnus Plate. Ploesoma huclsoni ( Bipalpus vesiculosus ) Zacharias, Wierzejski. Salpina mucronata Hudson. Euchlanis dilatata Cohn. Metopedia lepadella Gosse. Brachionus pala Gosse. „ rubens Gosse. „ bakeri Gosse. „ angular is Gosse. „ dorcas Gosse. „ mulleri Gosse. „ urceolaris Colin, Weber. „ furculatus Thorpe. Anuraea aculeata Plate. Pedalion mirum Hudson. In addition to the above list the males of the following 31 species have been seen at various times by Mr. John Hood, Mr. G. Western, Mr. P. E. Dixon-Nuttall, or myself, but no figures or descriptions of them have yet been published. Floscularia ornata. , , cornuta. t „ trilobata. 9 On the Male of Bhinops vifrea. By G. F. Bousselet. CEcistes umbella. „ pilula. „ crystallinus . * „ stygis. „ velatus. Synchseta pectinata. „ laltica (Gosse’s species, wbicb is not Ehrenberg’s). „ tavina. Triarthra longiseta. Notops minor. „ liyptopus. „ pigmasus. Notommata naias. Copeus collar is. ] Proales sordida. „ petromyzon. Eosphora digitata. Furcularia ensifera. Diaschiza semiaperta. Euchlanis lyra. „ oropha ( = parva ). ,, triquetra. Scaridium eudactylotum. Distyla gissensis. Pterodina patina. „ clypeata. „ elliptica. / 10 Transactions of the Society. III. — Second List of New Rotifers since 1889. By Charles JF. Rousselet, F.R.M.S. {Bead 1 6th December , 1896.) In August 1893 I published in this Journal a list of 186 new species of Rotifers described since the publication of the Supplement to the Rotifera by Hudson and Gosse in 1889. Since then 109 more new names have been added, which I have tabulated in the list below, and I append a Bibliography of the works in which those new species are described or discussed. My warning to avoid making new species out of slight varieties, and my recommendation to supply good figures and descriptions have unfortunately had very little effect. Out of 19 new species of Brachionus not less than seven are mere varieties of B. baheri , and Mr. C. H. Turner has named a new American Asflanchna merely because he could find only one point at the extremity of the jaws of some A. brightivelli instead of two, the normal but variable form; if he were to examine all the dogs he could find for such minute differences it is certain he would have to make a distinct species out of every Canis familiar is living. Some authors, again, have made new species with contracted spirit specimens of soft-bodied illoricate rotifers, such as Floscularia, Notom- mata, CEcistes , &c., of which they could not possibly know any real distinctive character ; and an empty shell of Gosse’s Pomjohohjx com - flanata has been absurdly described as a new species of Notholca, “ with a posterior opening for the passage of the foot ” when a foot does not exist at all in this genus ! In a number of other cases the figures and descriptions are quite useless as aids to future identi- fication. If the duplication of names goes on at this rate it is certain great confusion will follow. A few protests against the practice have indeed been raised, and it would be very desirable and in the interest of science if students of the Rotifera would exercise more care and dis- cretion, and avoid giving new names on the slightest pretext, when it is well known that in many cases the original figures and descriptions are not perfect or complete, and that most species are liable to con- siderable variation. Where in the following list there is no doubt about the identity of the species with a known form that name has been added in brackets, and I have marked with a (?) those species which are bad, or quite insufficiently figured and described. The numbers refer to the Bibliography at the end. List of New Rotifers since 1889. By C. F. Rousselet. 11 Rhizota. Floscularia atrochoides Wierzejski (93). „ libera Zackarias (96). „ cucullata Hood (68). „ brachiurus Barrois and Daday (60, 82) (?). „ trifidlobata Pittock (80). (Ecistes syriacus Barrois and Daday (60, 82) (?). Lacinularia elongata Shephard (87). Conochilus leptopus Forbes (66) (=(7. unicornis Rousselet). Bdelloida. Rotifer for fcatus Barrois and Daday (60, 82) (?). Gallidina fusca Bryce (59). „ plena Bryce (59). „ habita Bryce (59). „ angusta Bryce (59). „ eremita Bryce (59). New Genus. Cypridicola parasitica Daday (63). Ploima. I. Il-loricata. Asplanchna cincinnatus Turner (92) ( = A. brightwelli). Sacculus cuirassis Hood (69). Synchseta triophthalma Lauterborn (78). Polyarthra platyptera var. remata Skorikow (99). Triarthra ihranites Skorikow (99) (?). Notops macrourus Barrois (60, 82) (?). Taphrocampa viscosa Levander (79). „ clavigera Stokes (88). Pleurotrocha littoralis Levander (79). „ sigmoidea Skorikow (99). Notommata monopus Jennings (74). „ truncata Jennings (74). „ mirabilis Stokes (88, 84) ( = N. tripus). Copeus quinquelobatus Stokes (89, 90). Proales caudata Bilfinger (58). „ ( Notops ) laurentinus Jennings (74, 75). Furcularia longiseta var. grandis Rousselet (81). Bothriocerca longicauda Daday (62). New Genera. Adactyla verrucosa Barrois and Daday (60, 82) (?). Microcodides doliaris Rousselet (81). Ploima. II. Loricata. Mastigocerca hudsoni Lauterborn (77) ( = M. capucina Wierzejski) „ setifera Lauterborn (77). 12 Transactions of the Society. Mastigocerca lata Jennings (74). „ dubia Lauterborn (78). „ fusiformis Levander (79). „ curvata Levander (79). ., mucosa Stokes (88). Battulus sulcatus Jennings (74, 75, 58). „ palpitatus Stokes (88, 84). „ bicornis Skorikow (99) ( = B. bicornis Western). „ collaris Rousselet (83). Biurella neapolitana Daday (62) „ brevidactyla Daday (62) (?) Dinocharis truncatum Whitelegge (95) Stepha?iops emarginatus Bilfinger (58) ( = St . intermedins Burn). „ bisetatus Ternetz (91). „ variegatus Levander (79). Salpina macrocera Jennings (74). „ similis Stokes (88, 84) ( = S. macracantha Gosse). Diplax videns Levander (79). Diplois trigona Rousselet (81). Euchlanis plicata, Levander (79). Cathypna leontina Turner (92) ( = Distyla ichthyoura Shephard). „ appendiculata Levander (79) ( = Dislyla ichthyoura Shephard). ,, affinis Levander (79). Distyla spinifera Western (94). „ signifera Jennings (75). Monostyla truncata Turner (92) (?). „ tentaculata Cosmovici (61). „ lamellata Daday (64). ,, ovata Forbes (66) (?). „ hamata Stokes (88). „ robusta Stokes (88). „ bipes Stokes (88). Colurus margoi Kertesz (76). „ agilis Stokes (89). Metopedia elliptica Turner (92) (?). ,, dentata Turner (92) (?). „ pterygoida Dunlop (98). „ lepadella var. collaris Levander (79). ,, collaris Stokes (88). Pterodina incisa Ternetz (91). 5, parva Ternetz (91). „ bidentata Ternetz (91) ( = L. emarginata Wierzejski). „ crassa Levander (79). Brachionus rhenanus Lauterborn (77, 86, 97) { — B. brevispinus var. Ehrb. „ tuberculus Turner (92, 97) ( = B . bakeri var.). List of New Botifers since 1889. By G. F. Bousselet. 13 Brachionus melhemi Barrois and Daday (60, 82, 97) ( = B. balceri Ehrb.). ,, bur savins Barrois and Daday (60, 82). „ caudaius Barrois and Daday (60, 82) ( = Schizocerca diversicornis var. ? Daday. „ obesus Barrois and Daday (60, 82, 97) ( = B . bakeri var.). „ pyriformis Barrois and Daday (60, 82). „ angusticollis Kertesz (76). ,, quadristriatus Kertesz (76). „ bidentatus Kertesz (76). ,, quadridentatus Kertesz (76). „ granulatus Kertesz (76, 97) ( = B . bakeri). „ reticulatus Kertesz (76) ( = B. quadratics ? Bousselet). „ entzii France (67, 86, 97) ( = B. brevispinus). „ pentacanthus France (67, 86) ( = B . pala var.). „ cluniorbicularis Skorikow (85, 86, 97, 99) ( = B . baker i var.). „ lineatus Skorikow (99) ( =B . punctatus Hernpel). „ variabilis Hempel (71). ,, punctatus Hempel (71). „ mollis Hempel (71). Anursea aculeata var. platei Jagerskiold (72). „ cochlearis var. recurvispina Jagerskiold (72). „ eicliwaldi Levander (79, 81) ( = A. cruciformis Thomp- son). „ frenzeli Eckstein (65) { = A. aculeata). Notholca equispinata Cosmovici (61). „ orientalis Barrois and Daday (60, 82) ( = Pompholyx complanata Grosse). New Genera. Dictyoderma hypopus Lauterborn (77) ( = Ploesoma hudsoni Imliof). Cliromogaster testudo Lauterborn (77). " Gastroschiza truncata Levander (79). BIBLIOGRAPHY. N.B. — The works here enumerated contain the descriptions of the New Rotifers in preceding list, hut they are not, and do not pretend to be, a complete list of papers on Rotifera in general that have appeared during the period covered by the list. 57. Bergendal, Dr. D. — Gastroschiza triacantha n. g. and n. sp. Eine neue Gattung und Familie der Raderthiere. Bihang till K. Svenska Vet.-Akad. Handlingar, Band 18, IV. No. 4, 1893, 2 pis. 58. Bilfinger, L. — Zur Rotatorienfauna AYurtembergs. Jahreshcfte des Yereins f. Yaterl. Naturkunde in AYiirtt., 1894, pp. 35-65, 2 pis. u Transactions of the Society. 59. Bryce, David. — Further Notes on Macrotrachelous Callidinse , Joura Quekett Micr. Club, Y. pp. 436-55, 1894, 2 pis. 60. Barrois, Dr. Theod., and E. von Daday. — Resultats scientifiques d’un voyage entrepris en Palestine et en Syrie. Contribution a l’etude des Rotiferes de Syrie. Revue Biologique du Nord de la France, 1894, 1 pi. 61. Cosmovici, L. M. — Rotiferes, Organisation et Faune de la Roumanie. La Nature, 1892, pp. 41-5, 58-9, 70-1, 83. 62. Daday, Dr. E. von. — A Napolyi obol Rotatoriai (Rotifers of the Bay of Naples) (in Hungarian). Budapest, 1890, 2 pis. 63. Cypridicola parasitica. Ein neues Raderthier. Termeszetrajzi Fuzetek, XVI. (1893) 1 pi. 64. Beitrage zur Kenntniss der Microfauna der Natronwasser des Alfoldes. Math. u. Naturw. Berichte aus Ungarn, XT. ( 1893) 2 pis. 65. Eckstein, Dr. Karl. — Die Rotatorienfauna de.s Muggelsees. Ze it- schrift fiir Fischerei und deren Htilfsw., Heft 6, 1895, 5 pp., 7 figs. 66. Forbes, Prof. S. A. — Preliminary Report on the aquatic Invertebrate Fauna of Yellowstone Park, &c. From the Report of the U.S. Fish Commission for 1891 (published 29th April, 1893), p. 256 (no figures). 67. France, R. H. — Adatok Budapest Rotatoria faunajahoz. (Contri- bution to a Knowledge of the Rotatoria of Budapest.) Termes. Fuzetek, XYII. pp. 112-29, 2 pis. (in Hungarian and German). 68. Hood, John. — On Floscularia cucullata sp. n. Journ. Quekett Micr. Club, V. (1894), pp. 333-4, 1 pi. 69. Sacculus Cuirassis. International Journ. of Micr. and Nat. Sci., Oct. 1894, 1 pi. 70. On the Rotifera of the County Mayo. Proc. of the Royal Irish Academy, III. No. 4, 1895, pp. 664-706, 2 pis. 71. Hempel, Rudolph. — Description of New Species of Rotifera and Protozoa from Illinois River and adjacent waters. Bulletin of the Illinois State Laboratory of Natural History, IY. (1896) pp. 310-17, 5 pis. 72. Jagerskiold, Dr. L. A. — Ueber zwei baltische Varietaten der Gattung Anuraea. Zool. Anz., No. 438 (22 Jan. 1894) pp. 17-20, 2 figs. 73. Jennings, H. S. — Rotifers related to Euchlanis lynceus Ehrbg., Zool. Anz., No. 440 (Feb. 1894) pp. 55-6. 74. - — - A List of the Rotifera of the Great Lakes and of some of the Inland Lakes of Michigan. Bull, of the Mich. Fish Commission, 1894, No. 3, pp. 1-34, 1 pi. 75. Report on the Rotatoria. A biological examination of Lake Michigan. Bull, of the Mich. Fish Commission, No. 6, Appendix III. 1896, pp. 85-93, 1 pi. 76. Kertesz, K. — Budapest es Kornyekenek Rotatoriafaunaja. (The Rotifer fauna of Budapest and neighbourhood.) Inaug. Dissert., Budapest, 1894, 55 pp., 1 pi. 77. Lauterborn, Robert. — Beitrage zur Rotatorienfauna des Rheins und seiner Altwasser. Zool. Jahrbiicher, VII. (1893) pp. 254-73, 1 pi. List of New Rotifers since 1889. By C. F. Rousselet. 15 78 Lauterborn, Robert. — Die pelagischen Protozoen unci Rotatorien Helgolauds. Wissenschaftliche Meeresuntersueliungen aus der Biolog. Anstalt auf Helgoland, I. (1891) pp. 207-13, 2 figs. 79. Levander, K. M. — Materialien zur Kenntniss der Wasserfauna in der Umgebung von Helsingfors. Acta Societatis pro Fauna et Flora Fennica, XII. No. 3, 1-72, 3 pis., Helsingfors, 1891 (pub. July 1895). 80. Pittock, Dr. Geo. M. — On Floscularia trifidlobata. Journ. Quekett Micr. Club, VI. (Nov. 1895) pp. 77-8, 1 pi. 81. Rousselet, Charles F. — On Diplo'is trigona sp. n. and other Rotifers. Journ. Quekett Micr. Club, VI. (Nov. 1895) pp. 119-26, 2 pis. 82. Syrian Rotifers. Science Gossip, April 1895, pp. 29-31, 15 figs. 83. Battulus collaris sp. n. and some other Rotifers. Journ. Quekett Micr. Club, VI. (Nov. 1S96) pp. 2G5-70, 1 pi. 81. Structural Features in Rotifera. Science Gossip, Dec. 1896, p. 189. 85. Skorikow, A. S. — Preliminary Report of Observations on the Ro- tifers and Thysanura of the neighbourhood of Kharkow (in Russian). 1891, 9 pp. (no fig.). 85. Sniezek, Prof. Johann — Bemerkungen zu den jfingst aufgestellten Brachionus Arten. Biol. Centralblatt, XV. No. 16 (1895) pp. 602-5. 87. Shephard, J. — A new Rotifer, Lacinulciria elongata. The Victorian Naturalist; XIII. No. 2 (May 1896) pp. 22-1, 1 pi. 88. Stokes, Dr. A. C. — Some new Forms of American Rotifera. Annals and Mag. of Nat. Hist., July 1893, pp. 17-27, 2 pis. 89. Notes on the Genus Apsilus and other American Rotifera. Journ. Royal Micr. Soc., 1896, pp. 269-78, 1 pi. 90. Structural Features in American Rotifera. Science Gossip, 1896, pp. 121-2 and 118-9. 91. Teijnetz, Carl — Dio Rotatorien der Umgebung Basels. Basel, 1892, 51 pp., 3 pis. 92. Turner, C. H. — -Notes upon the Cladocera, Copepoda, Ostracoda, and Rotifera of Cincinnati, with descriptions of new Species. Bull. Denison University, VI. (1892) Rotifers, pp. 57—66, 1 pi. 93. Wierzejski, Prof. A. — Floscularia alrochoides. Zool. Anz., No. 126 (1893) 1 fig. 91. Western, G. — On Distyla spiniferci sp. n. Journ. Quekett Micr. Club, V. (Dec. 1891) pp. 127-8, 1 pi. 95. Whitelegge, Thomas — List of the Marine and Fresh-water Fauna of Port Jackson and Neighbourhood. Sydney, 1889, 161 pp. (no figs.) 96. Zacharias, Dr. Otto — Forschungsberiehto aus der Biol. Station zu Plon. II. Theil (1894) p. 83, 2 figs. 97. Rousselet, C. F. — On Brachionus baikeri and its Varieties. Journ. Quekett Micr. Club, VI. (to be published April 1897) 1 pi. 98. Dunlop, M. F. — On Metopcdia pterygoida , a new Rotifer. Journ. Quekett Micr. Club, VI. (to be published April 1897) 1 pi. 99. Skorikow, A. S. — Rotatoria of the neighbourhood of Kharkow (in Russian). Kharkow, 1896, 168 pp., 1 pis. 16 SUMMARY OF CURRENT RESEARCHES RELATING TO SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY (principally invertebrata and cryptogamia), MICROSCOPY, Etc. Including Original Communications from Fellows and Others .* ZOOLOGY. VERTEBRATA. a. Embryology*! Menstruation and Ovulation of Macacus rliesus.J — Mr. W. Heape has published an abstract of the results of his investigations made on specimens of this monkey collected in Calcutta in 1891. The creature seems to have a definite breeding season, but it is quite certain that in different parts of India the breeding season occurs at different times of the year. Menstruation is marked by a number of prominent signs, and there is a regular menstrual flow. The tissue changes which take place during the menstruation of 31. rhesus are very similar to those which the author has already described for Semnopithecus entellus. The results arrived at by the study of the second species entirely confirm the results led to by a study of S. entellus. The changes which take place in the eight stages into which the process of menstruation is divided are sketched. The author feels warranted in asserting that the regular occurrence of menstruation without ovulation, even though it be in the non-breeding season, is sufficient evidence that ovulation is a distinct process, and that it depends upon a law or laws other than those which govern menstruation. No trace of a blood-clot within the follicle was seen, and therein the ruptured follicles of 31. rhesus differ from what is usually described as a normal ruptured follicle in the human female. This difference between two animals, both of which undergo menstruation, is remarkable and * The Society are not intended to be denoted by the editorial “ we,” and they do not hold themselves responsible for the views of the authors of the papers noted, nor for any claim to novelty or otherwise made by them. The object of this part of the Journal is to present a summary of the papers as actually published , and to describe and illustrate Instruments, Apparatus, &c., which are either new or have not been previously described in this country. f This section includes not only papers relating to Embryology properly so called, but also those dealing with Evolution, Development and Reproduction, and allied subjects. X Proc. Roy. Soc. Loud., lx. (1896) pp. 202-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 17 worthy of special attention. The author has some reason for believing that the difference may be due to the presence or absence of the breeding season in monkeys, and to periods in the human female which are in the one case favourable and in the other case not favourable to conception. If this be true the period of the human female which is unfavourable to conception would be comparable to the non-breeding season of monkeys, and the period favourable to conception with the breeding season of monkeys. It is not of course maintained that amongst civilised peoples at the present day there are definite breeding and non-breeding times. The comparison is in harmony with the view that at one period of its existence the human species had a special breeding season. Amitotic Nuclear Division in the Egg of the Hedgehog.*— Mr. Matts Modems gives a report of some observations on the ovary of the hedgehog, which appear to indicate the presence of an amitotic process of nuclear division in the germinal vesicle. Only a few instances of this process have been observed, especially in Vertebrates, and, as for Mam- mals, there is no other indication than that of Flemming, and the egg with which that observer had to deal was not normal. Under these circum- stances, the author believes that his case presents some interest, although no general conclusions can be drawn from it. It is perhaps merely abnormal, and we will content ourselves with directing our readers’ attention to the paper. Oogenesis in the Mouse.f — Dr. J. Lange finds that two phases of oogenesis and follicle-formation must be distinguished in the mouse. The first is embryonic, the second begins after birth, and continues for a prolonged period. (1) A large number of germinal cells in the embryonic ovary form primitive ova ( Ureier ). At the time of birth the undifferentiated germinal cells form a membrana granulosa around the primitive ova. Thus arise primordial follicles. At an age of about four weeks complete follicles are found, but of these a large number atrophy. (2) At an age of 6-8 weeks a new proliferating phase sets in. Individual cells of the germinal epithelium differentiate into primitive ova; along with the adjacent indifferent germinal epithelial cells these are sunk into the stroma, and form primordial follicles. The formation of fresh follicles continues to an advanced stage in the life of the mouse. Division of Ovarian Qva4 — Prof. J. Janosik has made some remark- able observations on the ovarian ova of various Mammals, guinea-pig, rabbit, &c. The ovarian ovum may form, especially in young animals, regular polar bodies, or precisely similar bodies. Thereafter, without any fertilisation, it may divide into nucleated segments either equal or unequal. Besides these actual divisions, there are often fragmentations*, especially in older animals. As division goes on, the membrana pellu- cida is lost, as in normal development after fertilisation. Embryonic Variations and Growth. § — Dr. A. Fischel has studied the variability and growth of duck-embryos. Individual variations in length occur at all stages, and affect both the whole and its parts. An * Bill. K. Svenska Vet. Acad. Handlgr., xxi. iv. No 2 (1S95) 12 pp. and 1 pk f Verb. Phys. Med. Ge3. Wurzburg, xxx. (189(5) pp. 55-76 (1 pi.). X Arch. f. Mikr. Anat., xlviii. (1896) pp. 169-81 (1 pi.). § Morph. Jahrb., xxiv. (1896) pp. 369-401 (1 pi. and 10 figs.). 1897 c 18 SUMMARY OF CURRENT RESEARCHES RELATING TO embryo may be more tban one-balf larger than another of the same stage, and one with a single protovertebra may be as long as another with twelve. His results, taken along with those of Bonnet, Keibel, Mehnert, and Oppel, lead him to conclude that the variations in size also repre- sent differences in the internal structure of the parts. There seems to be no constant relation between the total length and the length of individual regions. In other words, proportions vary widely. Variations are commonest in the youngest stages, and decrease as differentiation increases. The correlations of the developing organs seem to have a regulating influence, narrowing the limits of variations in size and proportions. Fischel agrees generally with His, that absolute and relative growth in younger and older stages vary inversely, the former being greatest at first, but gradually decreasing. He adds that the intensity of growth varies with the individual, though there is always a relation of depend- ence between the intensity of relative growth and the total length of the embryo. Zones of intense growth are distinguishable, and the growth Foth of the whole length and of the several regions is periodic. A • “ plus ” of growth-energy in one region seems to imply a “ minus ” in another. The reasons for this remain obscure. Tooth-Genesis in Canid se.* — Hr. H. W. Marett Tims, in treating of the tooth-genesis in the Canidse, tells us that his main object was to trace the order of cusp-development, and the interrelationships of the various cusps in the tooth of the dogs, and to examine into the evidence, thereby obtained, bearing upon important and interesting problems of phylogeny. The author has been led to profound disagreement with Prof. Osborn, and he thinks that there are still other objections which may be urged against the tritubercular theory. These we need not sum- marise here. Suffice it to say that neither the tritubercular theory nor the multitubercular theory satisfies the author, and he proposes instead the theory of “ cingulum cusp-development.” This theory, we are told, is supported both by palaeontological and embryological evidence. The following are said to be the points in its favour : — (1) It har- monises more fully with what is known of the development of the teeth than either the tritubercular or multitubercular theory, the primary cone representing the reptilian cone and being always present. (2) It is quite possible and easy thus to homologise the cusps of all teeth, except perhaps the derivatives of the multituberculate type. (3) It is in accordance with palaeontological history. (4) No supposed rotation of cusps is required. Dentition of Manatee.t — Prof. W. Kiikenthal has studied an embryo of Manatus latirostris G*85 cm. in length, and establishes as the dental 3003 formula of the embryo — • In the course of phylogeny, reductions took place first in the upper jaw, canines and premolars disappearing, while the incisors became rudimentary sooner than those of the lower jaw. The teeth of the lower jaw retained their function longer, but also became useless; the third premolar was the first to disappear; there- * Journ. Linn. Soc., xxv. (189G) pp. 445-80 (8 figs.), f Anat. Anzeig., xii. (1896) pp. 513-26 (10 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 19 after tlie teeth in front of it were also reduced. In relation to the back teeth, Kiikenthal finds evidence of no fewer than three successive dentitions taking part in the formation of the definitive tooth. The main mass is due to the first dentition, with its labial wall the prelacteal fuses ; the second dentition forms the rudiment of a lingual papilla. Development of Nostrils in Mammals.*' — Dr. H. Tiemann has studied this in various Mammalian embryos. Olfactory areas, thicken- ings of ectoderm in the front of the head, become pits and then pockets. There is no groove or furrow communicating with the mouth, nor does the maxillary process share in forming the primitive nasal cavity. The modification of pits into nasal cavities is mainly due to marginal growth and to epithelial fusion of the lateral and median nasal process. This epithelial fusion is replaced in the anterior region by a mesodermic mass which forms firm tissue ; posteriorly in the part towards the mouth the epithelial bridge persists for a time. But by separation of the side walls it becomes reduced to a thin membrane (membrana bucco-nasalis) ; and it is only when this at length ruptures that a communication between nasal cavity and primitive mouth-cavity is established. Spermatogenesis in Salamander.f — Dr. Fr. Meves follows the suc- cessive generations of sperm-cells in Salamandra maculosa. He begins with the period of multiplication, describing the spermatogonia at rest and during division. The period of growth is next discussed. The third chapter has to do with maturation. The first maturation-division is heterotypic, the second homootypic, and there is no strict resting-stage between. Both are equation-divisions, not reduction-divisions. We have not been able to summarise this elaborate paper, but in a general way it may be said that the account given brings the spermatogenesis of the salamander into line with that observed in other cases. There is much agreement with Flemming, and very complete disagreement with vom Bath. Apart from the particular theme and such particular results as the absence of any reducing division, the memoir includes much general discussion of the cell and its parts and the processes of mitosis. Influence of Light on the Pigmentation of Salamander Larvae.}: — Prof. W. Flemming comments on Fischel’s recent research as to the influence of temperature on the pigmentation of salamander larvae. Flemming’s observations, repeated year after year, show that the larvae kept in dark aquaria remain dark, while those exposed to light, e.g. in porcelain dishes, become light, the temperature remaining fairly constant. Flemming also notes that the processes of the pigment-cells may persist in contraction, though they escape observation. Segmentation of Nervous System in Squalus Acanthias.§ — Dr. H. Y. Neal has made a study of the neural segments and their relations to nerves in embryos of this fish, and he has been led to the conclusion that in it there exists in early stages a continuous primitive segmen- tation, serially homologous through the head and trunk. This is the neuromeric segmentation. In later stages there appears in the brain a * Verh. Phys. Med. Ges. Wurzburg, xxx. (1890) pp. 105-23 (1 pi.), f Arch. f. Mikr. Anat., xlviii. (1896) pp. 1-83 (5 pis.), j Tom. cit., pp. 369-74. § Anat. Anzeijr., xii. (1896) pp. 377-91 (6 figs.). c 2 20 SUMMARY OF CURRENT RESEARCHES RELATING TO secondary segmentation, which gives rise to an anterior cephalic tract which is a region sui generis. The author traces the development of the neuromeres, compares the structures of the segments of the brain with those of the spinal cord, and notes the relation of the neuromeres to the sensory and motor nerves, to the mesodermal somites, and to the visceral arches. Dr. Neal thinks that the most important conclusion to which he has been led by his studies is that there is a serial homology between preotic and postotic segments in the Vertebrate head. The reason for this is to be found in the unbroken continuity of the postotic and preotic neuromeres ; their exact similarity on the grounds of rela- tions with nerves, somites, and visceral arches ; and, thirdly, the distri- bution of postotic fibres to preotic musculature. Genital Ducts of Teleosteans.* — Herr G. Schneider has studied the development of the genital ducts in Cobitis taenia and Phoxinus laevis. The oviducts arise from nephridial funnels in the same manner as the Mullerian ducts of other Vertebrates. The vasa deferentia are homo- logous with the oviducts, and, like them, correspond to the Mullerian ducts in other types. In respect of this homology between vasa deferentia and oviducts, the Teleosteans are primitive. Schneider is also inclined to derive the central testicular canal in higher Vertebrates from the cavity of the testes in Teleostei, which, again, is homologous, with the ovarian cavity. Larval Development of Amia calva.j — Mr. Bashford Dean has an interesting paper on the larval development of Amia calva. He describes the habits of tho larvm, the typical stages from the second day before hatching to the end of the fifth week, and some features of the organo- geny. The larvae of the fifth week, though scarcely an inch long, have practically attained their adult conditions, even as to fins, scales, and teeth. In the aquarium, the newly hatched fish remain inactive for several days lying on their side, attached to the floor by the sucking disc. Before the end of a week they have become restless, and in the second week (in natural conditions) they attend the male in immense swarms. There is ground for believing that the guardian’s care of the young lasts for about four weeks. Passing over the author’s description of the larvae of successive days* we shall note a few of his results as regards organogeny. The formation of the mouth differs little from that in Lepidosteus . sturgeon, and Telcosts. At no time do the appearances add evidence to the view that the mouth is of gill-slit origin. The anus is formed about the beginning of the second day ; a hint of a proctodaeum occurs ; throughout the early stages in the growth of the tail region there is no trace of a neurenteric canal, the neural axis being solid to begin with. The author gives a careful account of the origin of the liver as a broad dorsal fold of the gut, and amplifies his previous notes on the relation of yolk-sac to gut. Jungersen’s results as to the pro- and mesonephros are virtually confirmed. Brain and spinal cord originate from a solid ectodermic thickening ; * Mem. Acad. St. Petersb., ii. (1895) 20 pp. and 2 pis. t Zool. Jal.rb. (Abth. Syst.), ix. (1896) pp. 639-72 (3 pis. and 17 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 21 Amici differs from the sturgeon in the mode of its brain development, mainly in its tendency to differentiate the roof of the epencephalon and to reduce the calibre of the infundibulum. The transitions towards Teleostean conditions are noteworthy. In fact the brain of the bony fish is so closely Amioid that it may reasonably be looked upon as but a high degree of specialisation of this neo-ganoidean type. The ap- pearance of the hypophysis is late and inconspicuous. There appears to be no evidence that the auditory sac appears as in Serranus. The sucking discs are s|)ecialised pit-organs or sense-buds, precociously developed and enormously enlarged. Indeed precocious development is one of the most striking general features in the organogeny of Amia. The general systematic conclusion is that the development of Amia confirms the palaeontological evidence as to the derivation of Clupeoid Teleosts from Amioid Ganoids. Blastoderm Margin in Salmonidas.* — Herr Fr. Kopsch describes some experiments on trout embryos, which go to show that a concrescence in the manner formulated by His does not occur in Salmonidae. On the cellular ring or margin of the blastoderm an embryogenic region must be distinguished from a portion which is not directly formative. In the embryogenic portion, which lies in the position of the first invagination, the portion near the middle line, whose cells form the head, must be distinguished from the cell-groups on each side, which in the course of development meet in the middle line and form the kuob or Knopf. This represents a centre of growth from which trunk and tail are formed. In this formation, cells belonging to the non-formative portion do in the course of the growth round the yolk reach the Knopf and are there used in the formation of the embryo. Syncytium in Cleavage of Belone acus.t — Herr J. Sobotta describes an interesting stage in the development of this fish. When there are about eighty cells formed, the centre of the blastoderm develops quickly and becomes several layers thick, while the periphery remains a single layer. A few minutes later the peripheral cells become indistinct and form a syncytium. This happens repeatedly. The whole yoke syncytium in this case is observably due to a fusion of blastomeres. jS. Histology. Relation of Centrosomes to Cytoplasm.;]; — Herren K. Kostanecki and M. Siedlecki report at great length on the results of their study of Ascaris ova. The attraction spheres merely represent areas free from vitelline substance. It is important, however, to distinguish the c; microsphere,1 ” a particular portion of the whole mitom or aster, representing a special differentiation of the rays in the centre of the radiation. A detailed discussion of the archoplasm results in the conclusion that this conception, in Boveri’s sense, cannot be sustained. Throughout the whole cell there is a fine framework of plasmic threads, ending peripherally in a distinct marginal zone. The plasmic * Verh. Anat. Ges. X. in Anat. Anzeig. Erg. Hft., xii. (189G) pp. 113-27 (10 figs.). •f Tom. cit., pp. 93-100 (5 figs.). % Arch. f. Mikr. Anat., xlviii. (1896) pp. 181-273 (2 pis.). ] 22 SUMMARY OF CURRENT RESEARCHES RELATING TO fibrils of mitosis arise by a differentiation of this framework. A reti- cular arrangement is suggested, but not conclusively demonstrated. The fibrils around tbe centrosomes have an exquisite microsomal structure. The microsomes occur in groups on the fibrils at equal distances from the centrosome, and thus a concentric system appears. This mitom- system is indubitably the seat of the contractile forces of the plasm. The interfilar substance is probably trophic. The centrosomes are specific and essential parts of the cell, morphologically independent and persistent “ organs,” serving as insertion centres for the radii. The authors support on the whole the conclusions of Flemming, vanBeneden. and Heidenhain ; andjbesides stating their own results, give a useful — if somewhat prolonged — account of the views of others. Protoplasm of Nerve-Cells.*' — Dr. S. Ramon y Cajal finds that the cytoplasm of many nerve-cells, both of Vertebrates and Invertebrates, includes numerous chromatin patches. These are possibly of nutritive value, for the conducting part is the achromatic spongioplasm. The phy- logenetic and ontogenetic phases of the distribution of chromatin in the cytoplasm of nerve-cells are : — (1) diffuse and inconspicuous, (2) peri- pheral, (3) circumnuclear and peripheral, (4) throughout the whole cell. There is a relation between the dimensions of the patches and the volume of the protoplasm, but not between the chromatin differentiation and the functional dignity of the cell. The nucleus of nerve-cells becomes simpler as differentiation advances, the nuclein being concen- trated to one or two spherical nucleoli. Nerve-Endings of Duck’s Bill.| — Dr. L. Szymonowicz finds (1) that the tactile cells ( Tastzellen ) of Grandry’s and Herbst’s nerve-corpuscles are of connective-tissue origin ; (2) that this differentiation of connective cells occurs under the influence of the nerve-fibres; (3) that Merkel’s corpuscles (of epithelial origin) are sharply distinguished from Grandry’s and cannot be brought into the same histological or histogenic group. Inner Root-Sheath and Papilla of the Hair.}-— Herr Gunther shows that the several layers of the skin are represented not parallel to the longitudinal line of the hair and the inner root-sheath, but at right angles thereto. In the inner root-sheath the basal cell = stratum cylindricum ; the adjacent cells without keratohyalin = the lower cells of the stratum dentatum ; the cells with keratohyalin = the upper cells of the stratum dentatum and the cells of the stratum granulosum. The limit of cornification in the internal root-sheath corresponds to the stratum lucidum, and the horny part to the stratum corneum. The inner root-sheath, [with its matrices, is to be considered as an elongated piece of epidermis of protective, guiding, and fixing function. Pigment-Cells.§ — Dr. A. Fischel refers to a recent paper by Prof. Lubarsch, where his views are placed in incorrect antithesis to those of Reinke. The main difference between Fischel’s conclusions and Reinke’s seems to be that Fischel finds two kinds of pigment-cells in the sala- mander’s peritoneum, while Reinke finds only one kind. Fischel’s two * Ann. Soc. Espan. Hist. Nat., v. (1896) pp. 13-46 (6 figs.). f Arch. f. Mikr. Anat., xlviii. (1896) pp. 329-58 (1 pi.). X Verb. Anat. Ges. X. Vers, in Anat. Anzeig. Erganzhft. xii. (1896) pp. 183-9 (5 figs.). § Anat. Anzeig., xii. (1896) pp. 526-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 23 kinds are unconnected by transitional forms and behave differently under the influence of warmth. Phagocytosis by Blood-Plates.* * * § — Dr. S. Kamon y Cajal has demon- strated the occurrence of phagocytosis (of carmine particles and Bacteria) in the blood-plates of lower Vertebrates, such as the frog. Function of Interstitial Cells of Testis. f — Herr J. Plato has studied the testes of cat, mouse, &c., and has been led to the conclusion that, in the cat at least, the interstitial cells serve for the absorption and storage of fat, which is used in the nutrition of the ripening spermatozoa. He has discovered fine canals, which conduct the stored material to where it is used up. Regeneration of Mucus Epithelium of Intestinal Tract in Amphi- bia.!— Dr. C. Sacerdotti finds that in the oesophagus and stomach of the frog and in the intestine of the newt, the mucus epithelium is formed from elements which acquire their function of mucus-secretion before they reach their final position. Their centre of formation is in the deeper strata of the gut-wall, whence the elements reach the surface, partly by the wearing off of the old superficial epithelium, partly because they are pressed out by younger elements which arise beneath them. Thus he confirms Bizzozero’s conclusion that the mucus-cells are specific elements, and that the intestinal epithelia do not usually arise where they are seen in their fully differentiated state. y. General. Sexual Dimorphism and Variation^ — Prof. J. Kennel gives the following summary of an interesting essay : — Male and female are normally similar in those external characters which are not in direct relation with reproductive functions (sexual homomorphism). The two sexes usually show parallel variations, a parallelism which may be due to the similar action of similar causes, or may be the result of transference from one sex to the other. Deviations from previous characters may be gradually increased, or they may be of sudden origin (saltatory variation). Variations are not planless, but arise according to the species in definite directions, not always in one, yet not in very many. It is thus that varieties and new species arise. Variations in a definite direction may sometimes be increased in a high degree, even beyond the limits of utility and advantage (evolution- tendencies). Conditions may arise in which external organs regress or degenerate to the advantage of reproductive function. This is especially true of the female sex, in which the reproductive function demands more material sacrifice and more complex substances. Thus arises “individually conditioned ” sexual dimorphism. At first this need not be transmitted, as it arises from similar causes * Ann. Soc. Espan. Hist. Nat., v. (1896) pp. 5-12 (2 figs.), t Arch. f. Mikr. Anat., xlviii. (1896) pp. 280-801 (1 pi.), j Tom. cit., pp. 359-69 (1 pi.). § Schriften Nat. Ges. Jurjeff (Dorpat) ix. (1896) pp. 1-64. 24 SUMMARY OF CURRENT RESEARCHES RELATING TO in successive generations of females, yet it may become predominant, habitual, and hereditary, with transference to the males as well. If the transference to the males does not hinder in any way the male reproduc- tivity, it may become a constant character, and thus arises a secondary similarity of the sexes. But if the transference be in any way antago- nistic to the male reproductive functions, those forms which exhibit it will be eliminated. In established sexual dimorphism the secondary sexual characters cease to be mixed, since the essential reproductive differentiation limits this both positively and negatively. If the gonads become rudimentary the limits arc removed, and one sex may show the characters of the other, as in many, perhaps most, casual hermaphrodites. The frequently regular occurrence of male and female characters on the two sides of the body 'depends upon a preponderance of one half of the body. Useless organs degenerate not in consequence of disuse, but only in consequence of the greater use or development of other organs, by which their substance is claimed. In Lepidoptera, sexual selection has but a slight role, if any, in the phenomena of dimorphism. “Bipolarity” in Distribution of Marine Animals.* — Ur. A. E. Ortmann begins an interesting essay by stating the general interpretation of the similarity between Arctic and Antarctic marine animals. It has been expounded especially by Theel, Pfeffer, and Murray, and is as follows : — In association with the climatic differentiation which occurred at the poles at the beginning of the Tertiary period, certain polar members of the universal tropical fauna adapted themselves to the change. This adaptation occurred in a similar fashion at the two poles, and the gradual cooling having done its work, produced conditions of environmental uniformity which inhibited further change. As varia- tion continued more abundantly in the warmer waters the distinctions between polar and tropical fauna became more and more marked' Ortmann objects (1) that there is no warrant for supposing a de- creasing transformability in polar animals ; (2) that in many cases the similarity of north and south polar forms is secondary, and depends upon abyssal migration from one pole to the other; (3) the apparent bipolar distribution of deep-sea animals is only apparent, the facts are insufficient to warrant the induction ; (4) in some cases the bipolarity is due 'to littoral migration from north to south ; (5) the theory breaks dowrn entirely when applied to Decapod Crustaceans. Contrasts in the Marine Fauna of Great Britain, f — Prof. W. C. MTntosh has put together some of the impressions made by an exami- nation of the littoral fauna, and that within a few miles of the shore, at the four points of the compass in the British area ; for the north, the Shetlands, for the south, the Channel Islands, for the east, St. Andrew’s, and for the west the Outer Hebrides have been selected. It is, of course, impossible for us to analyse a paper which is full of details and names, so that we must content onrselves with quoting the conclusion. “ Limited * Zool. Jalirb. (Abth. Syst.), ix. (1896) pp. 571-95. t Ann. Mag. Nat. Hist., xviii. (1896) pp. 400-15. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 25 as the area we have been considering is, it is apparent that, while some forms are common to all, certain restraining influences check the spread of others, so that they become more or less characteristic of the several regions. Moreover, the mixed nature of the fauna shows that we have to do with several sources of origin, some of which date back to geo- logical periods marked by a different arrangement of the land, and a consequent change in the temperature of the water.” Biological Examination of Lake Michigan.* — Dr. H. B. Ward edits a bulletin on this subject, describing the lake with its fauna and flora, and with speciaPreference to the plankton. His general conclusions in regard to the plankton are the following: — The plankton is the source of food supply ttf all lake fish ; its rapid reproduction affords a constant supply in spite of continued destruction. The amount of plankton in Lake Michigan in tho (Transverse Bay) region examined is limited. The enormous area compensates for this limited amount. The plankton is uniformly distributed horizontally. In summer it is accu- mulated near the surface, and very little occurs below 25 metres, except near the bottom. The uniform horizontal distribution of the plankton indicates that the plankton-eating fish find food in limited quantities everywhere. The bottom flora and fauna are not enough to support large numbers of bottom-feeding fish within circumscribed areas. The well-known migrations of whitefish schools along shore seem thus to be correlated with the non-localised food supply. There is a plentiful supply of whitefish food on the old fishing-grounds. No reason can be assigned for the diminution in numbers except overcatching. By intro- ducing suitable vegetation, the fish-producing powers of the lake might be vastly increased. Dive appendices contain brief accounts of the aquatic plants, by H. D. Thompson ; Protozoa, by C. A. Kofoid ; Rotifera, by H. S. Jennings ; Turbellaria, by W. M£M. Woodworth ; and Mollusca, by Bryant Walker. Poisoning of Freshwater Animals by Hypochlorite of Lime.f — Prof. R. Dubois has investigated this not uncommon event. Trout are particularly susceptible, being readily asphyxiated. Other fishes resist longer, but eventually succumb. Crayfish and other freshwater animals also perish. Trout killed by hypochlorite of lime are readily recognised by their discoloration, &c., and should never be bought. Not that they are injurious, but the practice of thus poisoning them is quite fatal to the stream. Tunicata. Distribution of Doliolum.J — Dr. ^ • Borgert has worked over the specimens of Doliolum collected on the ‘Yettor Pisani’ expedition. No new species were found, but the recording of D. tritonis and D. nationalis in the Pacific is new. The number of species found in the Atlantic Ocean is the same as that from the Pacific, but the actual species are not quite the same. Thus D. 7-arum Grobben is not known from the Pacific, nor D. ajfline Herdman from the Atlantic. * Bull. Michigan Fish Comm., No. 6 (1896) 100 pp. and 5 pis. t Ann. Soc. Linn. Lyon, xlii. (1895) pp. 49-52. t Zool. Jahrb. (Abtli. Syst.), ix. (1896) pp. 714-9. 26 SUMMARY OF CURRENT RESEARCHES RELATING TO INVERTEBRATA. Freshwater Fauna of the Azores.* — Mr. J. Richard gives an account of the freshwater fauna of the Azores, as observed on the visits of the yacht £ Princess Alice.’ A short account is here given of the Ostra- coda, Copepoda, and Cladocera. Attention is called at the same time to the presence in the islands of Plumatella repens , and the discovery in them, for the first time, of the genus Mermis. It appears to be certain, notwithstanding some doubts, that the remarkable rotifer Pedalion mirum does exist in the Azores. The author recommends the study of the island of Flores, the peculiarities of which show that it merits a thorough zoological exploration. Adelotacta Zoologiea.f — Sig. F. S. Monticelli describes under this title ( = of doubtful classification) two remarkable forms, Pemmatodiscus socialis g. et sp. n. and Treptoplax reptans Montic, The former is a very simple organism, corresponding to the gastrula type, with two layers of epithelium separated by a coelomic cavity. The outer layer is a high ciliated epithelium with characteristic rhabditoid structures : the inner layer is lower and non-ciliated. A distinct ciliated mouth puts the gastrular cavity in communication with the outer world. There are no traces of organs or sexual elements, but the organism multiplies by division, which is, of course, an argument against its being a larva. It was found in cysts in the jelly of Rhizosloma pulmo. The author com- pares it to Korotneff’s Gastrodes parasiticus. The second form, which the author described in 1893, is also very simple, and has three strata — an external dorsal of flattened non-ciliated cells ; an external ventral of elongated, clavate, flagellate cells ; a me- dian of large, irregularly polygonal elements in three rows. Adhering to the lower surface of the dorsal stratum are numerous refractive cor- puscles or globules enclosed in modified cells. The animals were found adhering to the sides of the aquaria at the Naples Station. They change their form incessantly, like Amoebae, and multiply by division. Monti- celli compares it in detail with other forms, especially Trichoplax ad- hserens. He concludes that Trichoplax , Treptoplax, and Pemmatodiscus must at present remain Adelotacta. Mollusca. Indian Deep-Sea Molluscs.:} — Mr. E. A. Smith describes twelve new species of deep-sea molluscs, collected by the survey steamer ‘ Investi- gator.’ Some of these are extremely interesting on account of their re- markable form and surface ornamentation ; others are peculiar on account of their close similarity to species which occur in the North Atlantic ; in one instance the author can find indeed no distinguishing features between the Atlantic and Indian Ocean specimens. Mode of Life of Lima hians.§— Dr. J. D. F. Gilchrist has an inter- esting article on this mollusc, great quantities of which are to be obtained by dredging off Millport. The two organs of most importance are the * Bull. Soc. Zoo!. France, xxi. (1896) pp. 171-8. f MT. Zool. Stat. Neapel, xii. (1896) pp. 432-62 (2 pis.), i Ann. Mag. Nat. Hist., xviii. (1896) pp. 367-75. § Trans. Nat. Hist. See. Glasgow, iv. (1896) pp. 218-25. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 27 foot and the mantle, and the author gives an account of the chief purposes to which these are put. He points out that, in trying to understand the habits and mode of life of this animal, he has but raised a few questions which he cannot answer, and that many more questions remain to be raised. He is quite right, we think, in considering that this line of re- search is one that deserves increasing attention, and though it may be admitted to be a difficult work, it certainly offers a key to the solution of many scientific questions of the present day. It is a return to the older methods of Natural History study, but with increased means at our disposal for appreciating the significance of our observations. y. Gastropoda. Hermaphroditism of Limpet.* — Mr. J. F. Gemmill reports some causes of hermaphroditism in the limpet, and makes some observations regarding the influence of nutrition in this mollusc. As is well known, the sexes are ordinarily separate, and the sexual apparatus is of the simplest kind. The author has lately found at Millport several limpets in which a gonad was not purely ovarian or testicular, but of a mixed character. Under the Microscoj>e there were at once seen not only ripe ova and spermatozoa, but also segmenting ova, and even ciliated free- swimming embryos. This hermaphroditism is of a kind much simpler than is usually found in hermaphrodite species of the same order, and rather approaches the type seen in the common oyster. The peculiar habits and structure of the limpet may give a key to this occasional variation. As the limpet is solitary and practically fixed, and as it has no organs of copulation, and as no sexual congress of any kind has been observed, the meeting of ova and spermatozoa would seem to depend on chance, so that occasional hermaphrodites might be of benefit to the species. The number of such variations, however, is too small to allow this consideration much weight. Apparently they have till now escaped observation altogether, and out of about 250 specimens the author found only three hermaphrodites. With regard to the stations they occupy, limpets may be divided into high-level, middle-level, and low-level forms, and it is clear that the amount of nutrition which these three kinds would get would differ considerably. One might expect that if nutrition has any influence on sex, such an influence would make itself seen in the different proportions of male and female specimens at different tidal levels. In accordance with current theories it may be thought that the low-level limpets, with their richer nutrition, would show a relatively greater proportion of females over males. Figures, however, show that this is not so ; and the conclusion must be come to that — in the limpet, at any rate — more abundant nutrition does not predispose to the female type. It must, however, be borne in mind that the female gonad of the limpet is not larger in bulk than the male, and does not, therefore, make special demands on nutrition. 8. Lamellibranchiata. Green Oysters again.f — Sig. D. Carazzi has made an elaborate study of the green oysters of Marennes. His chief conclusions are the * Anat. Anzeig., xii. (1896) pp. 393-4. f MT. Zool. Stat. Neapel, xii. (1896) pp. 381-431 (l pi.). 28 SUMMARY OF CURRENT RESEARCHES RELATING TO following. Lankester and Cliatin were in error in believing that the secreting cells or macroblasts contained the green pigment. These cells function as JBecherzellen , secreting a substance physically, but not chemi- cally like mucus. The opinion that the green coloration of the palps and gills is due to a transport of material from the gut by means of the amcebocytes of the blood is completely erroneous. De Bruyne’s facts, for instance, deal with pathological conditions. The presence or absence of the green diatom Navicula is of little moment in coloration. The green substance, or marennine, is a product of metabolism, and may be formed in a great variety of epithelial cells, though not in the BecJier- zellen and claviform cells. It is an organic substance, of peculiar com- position, with iron as one of its principal elements. It is perhaps a nutritive substance, and is carried by amoebocytes from epithelial cells to the liver. One of the results of the author’s studies is to show that the amcebocytes are of essential importance in nutritive transport. Arthropoda, a. Insecta. Colour- Variation in the Vanessas.* — Dr. F. Urcch adopts the view, especially emphasised by Eimer, that organisms are to be regarded as very complex material systems, and that therefore any change at one point must be accompanied by compensatory changes at other points. This view he illustrates by a tabular survey of the artificially produced colour-variations in Vanessa. His conclusions are — (a) that in ontogeny the effect of warmth is to deepen the tint of pigmentary colours by a concentration of the pigment at special points, rather than by an actual increase in amount ; and ( b ) that the continued action of heat through- out many generations produces an increase in amount of pigment and a deepening of tint, and of cold, a decrease in amount and a diminution of intensity of tint. The increase in amount may manifest itself either directly or indirectly as an increased complexity of chemical structure. In other words, colour-changes occurring during ontogeny are to be regarded merely as new positions of equilibrium ; but an increased temperature acting through many generations may lead to absorption of energy, and so to actual increase of pigment production. In estimating colour-change Urech emphasises the importance of realising that optical colours usually occur in non-pigmented scales, so that an increase in blue or violet (optical) colours may be due to an actual decrease in the amount of pigment present. If this be kept in mind, he is of opinion that almost all artificially produced colour- changes in the Vanessae mny be explained as correlated or compensatory changes. The paper contains also some additional arguments in favour of the author’s view, that the progression of colours observable during develop- ment in the Vanessae is to be regarded as a case of recapitulation. Bag-Shelter of Larvae of Australian Moths.j — Mr. W. W. Froggatt states that, in many parts of the Australian bush, one frequently comes across brown, liver-coloured silken bags, of an irregular funnel shape, * Zool. Anzeig., xix. (1896) pp. 163-74, 177-85, 201-6. t Proc. Linn. Soc. New South Wales, xxi. (1896) pp. 258-60 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 29 spun round a stout twig. They vary in size from 3-8 inches in dia- meter at the broad end. Upon examination, if freshly constructed, they will be found full of very hairy caterpillars, mixed up v/ith their castings and moulted skins. These curious structures are woven round twigs by the larvae of several different species of moths belonging to the genus Teara. They are constructed for shelter during the day, and are not used for pupating purposes. Hiding in them during the day, the cater- pillars issue forth at dusk, feeding all night, and return to cover at day- break. When moving about they travel in procession. The author gives a description of T. contraria. The larvse of this species live in communities of one hundred or more. About fifty speci- mens were collected and placed in a glass jar in the museum, where they remained huddled together in a mass, unless disturbed, when they would all set off in a procession round the walls of their prison. In about a fortnight they began to burrow into the loose sand at the bottom of the jar, constructing soft felted cocoons out of the hairs upon their bodies. Metamorphoses of Beetles.* — M. le Capitaine Xambeu describes, in a fifth memoir on the subject, the metamorphoses in numerous families of beetles. His twofold object is to aid towards securer classification, and to work out for economic reasons the exact life-history of practically important forms. Brain of the Bee.f — Dr. F. C. Kenyon has made a study of the brain of the common bee. A thousand or more brains were put into requisition. It appears to be evident that, though there are more diffi- culties in the way of obtaining good results than with Vertebrates, patient application of the bichromate of silver method will throw as much light upon the organisation of the hexapod nervous system as it has iq)on that of the higher animals. The minute structure of the so-called mushroom bodies has been brought to light, and it is now almost clear to demonstration that the function of these peculiar bodies is that of enabling the insect to intelligently adapt itself to its surroundings. The cups of these bodies are connected with two pairs of tracts of fibres from the optic lobes, with three from the antennary lobes, and with one from the ventral nervous system. The roots are very probably con- nected with the inner terminals of motor, or possibly of other efferent fibres, but the exact course of the connection and the number of cellular elements composing it remains to be demonstrated. The central body is plainly shown to be connected with the fibrillar arch and with the fibrillar mass in front and with that below it. Motor cells have been found in a ventral position in the ventro-cerebron, which does not accord with the distinction, based upon physiological experiments, of a dorsal motor and a ventral sensorial area for each ganglion of the ventral cord. The author reconciles the discrepancy by pointing out that it is the fibrillar connections that are destroyed, in the lesions produced dorsally, and the association cells and fibres and the terminals of sensory fibres in ventral lesions. Wasps. { — We would recommend all who are interested in these in- sects to read the short paper by Mr. Jas. Campbell, which breathes * Ann. Soc. Linn. Lyon, xli. (1894!) pp. 107-56 ; xlii. (1895) pp. 53-100. f Journ. Comp. Neurol., vi. (1896) pp. 133-210 (9 pis.). t Trans. Nat. Hist. Soc. Glasgow, iv. (1890) pp. 265-7. 30 SUMMARY OF CURRENT RESEARCHES RELATING TO throughout the true spirit of the field naturalist. He points out as an interesting fact, that away from human habitations wasps act differently towards people from those we meet near houses or by the roadside. The author thinks that perhaps the love of the wasp for what we call bad smells determines its best sphere of usefulness. The “ wet heap- rubbish, the emptying drain, the oozing cesspool, are evils that cry aloud for redress, and their cries are all the louder till vegetation comes to clothe them. On sewage-laden rivers, the herbage covers much that is unsightly, and lessens the effect of the hurtful odour. If it is better to have such places clothed with a mantle of green, and if we know that the wasp is a willing worker among the flowers that graciously cover places so uninviting, we cannot well fix the limit to the work it is doing, both openly and out of sight.” Remarkable Use of Ants.* — Mr. R. M. Middleton jun. records a re- markable use of ants in Asia Minor. He has made the acquaintance of a Greek gentleman who fell from his horse in Smyrna six years ago, and received a severe but clear cut on the forehead. In accordance with the custom of the country, he went to a Greek barber to have the wound dressed, and the barber employed at least ten living ants to bite the sides together. Pressing together the margins of the cut, which was rather more than an inch long, with the fingers of the left hand, he applied the insect by means of a pair of forceps held in the right hand. The man- dibles of the ant were widely opened for self-defence, and as the insect was carefully brought near to the wound, it seized upon the raised surface, penetrated the skin on both sides, and remained tenaciously fixed while the barber severed the head of the ant from the thorax, and so left the mandibles grasping the wound. These were left in position for three days, when the cut was healed and the heads removed. It is not yet certain what the species used is. The author refers to some obser- vations on the subject by Sir John Lubbock in his well-known work on ants, bees, and wasps. Thoracic Glands in Larvae of Trichoptera.f — Prof. G. Gilson gives an account of segmentally disposed glands in these insects. He comes to the conclusion that in larval Trichoptera each of the thoracic segments may be provided with more or less complex glandular organs, more nearly representing nephridia than the coxal glands of Annelids and Peripatus, and he carries this further by saying that in the Hexapoda re- mains of segmentally glandular organs, be they coxal or nephridial, are now known for the whole length of the body, from the mandibular to the posterior abdominal segments. Larval Gills of Odonata. * — Prof. G. Gilson and M. J. Sadones state the results of their investigations on the larval gills of the Odonata in the following terms : — (1) The rectal tracheal gills of larval Odonata are prevented from adhering to one another by the presence of three conical pillars. (2) The main tracheal tubes alone are lodged between the two that form the gill. The terminal loops, i.e. the functional part of the system, run through the protoplasm of the subcuticular layer. * Journ. Linn. Soc. Lend., xxv. (1896) pp. 405-6, t Tom. cl fc. , pp. 407-12 (2 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 31 (3) A blood-space communicating with the body-cavity exists in the rectal gills. (4) The oxygen seems to be absorbed through the tracheal loops by the action of the subcuticular protoplasm only, and to be discharged from this into the general tracheal system. (5) Carbonic acid, on the contrary, appears not to be carried to the gills by tracheal tubes, but by the blood alone. (6) In any case the blood would appear to play an important part in the excretion of carbonic acid, and a very unimportant part in the ab- sorption of oxygen. Gizzards of Odonata.* — Dr. F. Ris has studied the structure of the gizzard in a large number of dragon-flies, both adult and larval. The primitive form, as seen in Calopteryginae, has sixteen longitudinal areas, eight broad and eight narrow, which bear an armature of irregularly dis- posed teeth. In the typical Agrioninae the areas are more complicated, and the spines more regular; in Pyrrhosoma minium there is greater elaboration and concentration. In Lestes the areas are reduced to eight, which are differentiated into four broad and four narrow, each with peculiar and specialised armature. Among Anisoptera, Gomphus and JEschna show a reduction or concentration to four similar areas. Finally, Cordulegaster and the Libellulidm differentiate the four areas to two pairs of teeth, so that a primitively radial arrangement has become bi- lateral. These conditions are clear in the larvm, but obscured in the imagines, where the organ tends to be reduced. The reduction is least in Calopteryx, much more in Agrion, most in Gomphus and JEschna. In Cordulegaster and the Libellulidae there is in the adult but little trace of the larval conditions. On the basis of his researches, the author suggests the following scheme of relationships : — • Parasitic Beetles.f — Dr. G. Brandes notices an account of the beaver of the Elbe by H. Friedrich, to which is appended remarks on Platypsyllus castoris Ritsema. The history of this insect dates back to 1868, when it was brought before the Ashmolean Society by Westwood, * Zool. Jahrb. (Abth. Syst.), ix. (189G) pp. 596-621 (tigs. A-N). t Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 297-305. 32 SUMMARY OF CURRENT RESEARCHES RELATING TO who called it PI. castorinus . Priority of publication was, however, ob- tained by Ritsema by a period of 14 days. Both these naturalists located the insect among the Fleas. In 1872 the American coleopterologist Le Conte pointed out that the beaver parasite was a Beetle, and his conten- tion was supported later on (1886) by Riley in a communication entitled c Systematic Relations of Platypsyllus as determined by the Larva/ Thus it seems that the beaver of the Old and New Worlds is infested hy parasitic beetles which, according to some, belong to the same species. In the skin of the Alaska beaver another parasitic beetle, Leptinilhis validus Horn, having only rudimentary eyes, has been found, and in the skin of mice a perfectly blind example of the same family, Leptinus testaceus Mull. Megnin has described two other beetles parasitic on Rodents, Arnbly- cpinns Jelslrii and A. Mniszechi , but the author holds that their real parasitism is not proved. Resemblance of an Insect-Larva to a Lichen-Fruit.* — Mr. G. E. Stone points out the remarkable resemblance — which may possibly be mimetic — between the larva of the elm-leaf beetle, Gossyparia ulmi, re- cently imported into the United States from Europe, and the apothece of a lichen, say, PJiyscia hypoleuca ; the resemblance extending to size, form, and colour. Social Wasps of Brazil.f — A short note by Dr. H. von Ihering is of interest, as, with the exception of one note by him, all the facts we know with regard to social wasps have been learnt from the observation of European species, In some genera the societies are not dissolved in winter, but are perennial. Unlike what happens in Polistes and Vespa , where each society has but one fecundated female, which is much larger than the workers, there are in the societies of Polybia a number of fecundated females, and these females do not differ from the workers in size. The presence of a number of fecundated females is an important fact, and represents a condition which is relatively primitive. At first, of course, there were no workers in a colony, but only males and females. Specialisation could not have started with the immediate reduction of the fecundated females to one queen, but there must have been a partial reduction in numbers. These fecundated females became reduced in number, and at the end of the process there was only one. In Polybia we see one of these stages — numerous fecundated females with no difference between them and the workers. Life-History of Larvae of (Estrus4 — Dr. Ruser reports that he found in four oxen, which gave the ordinary external signs of being affected by this fly, transparent larvae in the loose connective tissue between the oesophagus and the body-wall. It would appear that the larvae arc able to bore through the wall of the oesophagus, and so to make their wray to the great vascular trunks in the region of the neck. It would appear, therefore, that the view' that the larvae of this fly enter- hy the mouth is correct. * Bull. Torrey Bot. Club, xxiii. (1896) pp. 454-5. f Bull. Soc. Zool. France, xxi. (1896) pp. 195-62. i See Centralbl. f. Bakteriol. u. Parasitenk, xx. (1896) p. 548, ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 33 Nervous System of Mecopo&inse.* — M. L. Bordas lias made a study of the stomatogastric nervous system of this tribe of Orthoptera. He has had the advantage of examining a large species — Platyphjllum giganteum. The stomatogastric system of this species consists of a frontal ganglion, a subcerebral ganglion, a pair of latero-oesophageal or intes- tinal ganglia. The large number of centres and the numerous branches which are given off from them, indicate clearly enough that this system must play a large part in the accomplishment of the digestive functions, and especially of those movements which are necessary for the complete trituration of the food. The author gives a sufficiently detailed account cof the facts of the anatomy of this species. £. Myriopoda. Notes on Lysiopetalidse/j’ — Dr. C. Yerhoeff describes Lysiopetalum lendenfeldi, a new species from Bosnia. Among his many detailed results, we note that the copulatory apparatus of Lysiopetalidae is formed from a single pair of segmental appendages, that the parts previously called Vorderarme are differentiations of the coxal parts, and that the Lysiopetalid® are, as regards their copulatory organs, far removed from lulidae, but near Polydesmidae. H. Arachnida. n Dermatobia noxialis.f — Dr. B. Blanchard has published some new 'observations on the larvae of this creature. Dermatobia noxialis is dis- tributed throughout the whole of intertropical America, but may extend north and south beyond the tropics. Notwithstanding the many obser- vations which have been made in the most varied countries and on the most diverse animals, and, notwithstanding the variety of names under which it is known, the cuticolar larvae of the genus Dermatobia , observed until now in man and domestic animals, belong to one species only — Dermatobia noxialis ; the two larval forms which have such distinctive characters are only two successive stages in the development of one species, and are separated the one from the other by an ecdysis, which ttakes place in the tumour where the larvae is developed. Another species of Dermatobia is found in South America, and, although apparently widely distributed, its larva is not yet known. It does not appear to attack either man or domestic animals. e. Crustacea. Byes of Decapods.§ — Herr B. Rosenstadt has studied the eyes of numerous Decapods, especially as regards (1) the pigmentation and its displacement, and (2) the relation of the crystalline cones and the optic rods (rhabdoms) to one another and to their matrix cells. Species of Lucifer , Sergestes , Virbius, Palsemon, Astacus , Pagurus, Ac. were included in his investigations. In each ommatidium there are (a) four iris-pigment-cells beside the * Comptes Rendus, cxxiii. (1896) pp. 562-4. t Zool. Anzeig., xix. (1896) pp. 465-77 (4 figs.). X Bull. Soc. Centr. Med. Vete'rinaire, 1896, 14 pp. and 3 figs, (separate copy). § Arch. f. Mikr. Anat., xlvii. (189G) pp. 748-70 (2 pis.). 1897 D 34 SUMMARY OF CURRENT RESEARCHES RELATING TO crystalline cones or cells, (b) two retinal-pigment-cells (four in GalatJiea ), while (c) the retinule-cells themselves are more or less pigmented according to illumination. The changes observed according to illumi- nation are described. Except in Lucifer and Sergestes , a granular, dirty-yellow “ tapetum ” was observed, associated with two cells in the posterior joart of each ommatidium. Following Exner, the author distinguishes and discusses eyes forming an apposition-image, a superposition-image, or the former in light and the latter in darkness. The rods are quite independent of the cones, the former arising from a group of retinule-cells, the latter from the epidermic crystalline cells. Variation in Portunns depurator.* — Mr. E. Warren has made on this crab seven’ measurements on each individual male, corresponding to those made by Prtf. Weldon on the male of Carcinus msenas. The total number of crabs measured was 2300, and the measurements were recorded to the tenth of a millimetre. Since the crabs were growing and varied much in size, it was found necessary to reduce the measures to percentages of some standard dimension. The carapace length was selected, and all the measurements are expressed as thousandths of this dimension. On glancing down the mean of the several dimensions it will be seen that a stable equilibrium is in no way reached, except, perhaps, in the case of the total breadth ; thus, throughout life, this crab- is gradually changing its shape, and it appears to be clear that, when all its organs are in a rapid state of change, the crab can protect itself. Here is an argument, Mr. Warren thinks, against the transmission of acquired characters, for otherwise the earlier brood would tend to have a somewhat different shape to the later, and this is scarcely probable. From the measurements which the author records, he believes himself to have proved that the mutual relationships of the organs measured are almost as closely similar between the two genera Porlunus and Carcinus as one or two more sharply marked off races of a single species* Of course, a considerable number of such comparisons would have to be made before any safe conclusion could be drawn, and the meaning of the differences observed by such comparative treatment of a large series of genera. The larger duration probably indicated real differences in the correlation constant, and are possibly associated with changes in the habit or environment. For example, it is conceivable that a crab which swims might require to be more symmetrical than one that only crawls between tide-marks. Changes in the Carapace of Carcinus Msenas.f— Mr. H. Thompson has made a study of certain changes observed in the dimensions of parts of the carapace of this common crab. The methods followed were those of Prof. Weldon. On comparing two sets of measurements it appeared that the average size of the “ frontal breadth ” of the crabs collected in the year 1893 exceeded that of the crabs collected in 1895. The de- ficiency in frontal breadth in 1895 appeared to be compensated for by the possession of a larger right dentary margin. As the results seemed to indicate that a change in regard to these dimensions was taking place in the species, it was thought desirable to compare similar measurements * Proc. Ptoy. Soc. Loud., lx. (1896) pp. 221-14 (6 figs.), f Tom. cit., pp. 195-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 35 in tlie adult. Two hundred and fifty-four specimens of the male of the crab had been collected in 1892-3 and were available for examination, while 493 individuals were collected at Plymouth in January of the present year. The results fully confirmed those arrived at for the young. It is not possible at present, of course, to say whether we have here indications of a permanent change, or whether there is mere oscillation such as, for all we know, may be constantly going on in the relative dimensions of the various parts of the members of all species. It is clear that a similar set of measurements must be taken two or three years hence. Lucifer Reynaudi.* — Herr B. Rosenstadt has made a study of the organisation and post-embryonic development of this very interesting decapod. After treating of its general form and integument, the author describes in considerable detail the extremities, the musculature of the body, and the nervous system. The intestine and its appended glands are also fully dealt with. The condition of the specimens did not allow him to dissect the blood-vessels. Special attention is called to the com- plete want of gills in Lucifer. With regard to the excretory organs, it is of interest to know that they have some resemblance to the glands described some time since by Mr. E. J. Allen, in the axis of the gills of Palsemoneies varians. In conclusion, the structure and development of the reproductive apparatus is dealt with. The author finds that the vasa efferentia are morphologically modified portions of the testis. The two spermatophoral glands may be referred to that portion of the rudiment of the generative apparatus which connects the rudiment of the testis with the ejaculatory duct. The azygous condition of the testis and its site below the intestine are secondary morphological peculiarities which appear in the course of post-embryonic development. At the end of his paper the author calls attention to a case of com- plete hermaphroditism. Peripheral Nervous System: | — Dr. B. Nemec describes the peri- pheral ganglionic strands which occur in certain Isopods. They are especially well seen in Titanethes, a blind genus. A thoracic segment shows a central ganglion directly connected by a nerve with the ventral cord, and from the central ganglion branches go to two lateral ganglionic plexuses lying under the hypodermis. Similar structures occur in Orcliestia among Amphipods. Visceral Nervous System of some Isopods.f — Dr. B. Nemec finds that Isopods ( Porcellio , &c.) have an anterior and a posterior visceral system, the former innervating oesophagus, gizzard, and hepatopancreas, the latter supplying mid-gut and bind-gut. The anterior starts from the circumoesophageal commissure, has a ganglion near the upper lip, another in front of the gizzard, and so on. The posterior system arises from the fused post-abdominal ganglia, and is without any gang- lionic differentiation. * Development of Asellus.§ — Prof. L. Roule adds to his previous embryological studies of Crustacea an account of the development of Asellus ciquaticus. In spite of the amount of yolk, segmentation is virtually * Zool. JB. (Abth. Anat.), ix. (1896) pp. 427-76 (6 pis.). t Anat. Anzeig., xii. (1896) pp. 434-8 (2 figs.). % Zool. Anzeig., xix. (1896) pp. 477-9. § Ann. Sci. Nat. Zool., ser. viii., i. (1896) pp. 163-96 (3 pis.). 36 SUMMARY OF CURRENT RESEARCHES RELATING TO total ; the conical blastomeres surround an undivided core. After the preliminary cleavages, the blastoderm (blastolecithe) becomes distinct from the yolk (deutolecithe) ; a zone of small cells surrounds a non- nucleated internal vesicle. The blastoderm becomes immediately double, differentiating the two primary layers. This is comparable to the ex- tension of the “ cicatricula ” in Porcellio and its conversion into the blas- toderm. The vitelline membrane disappears quickly, and is replaced by a cuticular layer, perhaps corresponding to a cuticle of a nauplius moult. The body of the embryo diminishes in size as the yolk is absorbed ; and splits dorsally in a peculiar fashion, as if bent on itself. At the two ends of the cleft there develop two rigid annexes, transversely elongated. These dorsal organs are adaptations peculiar to the embryo and without significance for the adult. The dorsal cleft and the separa- tion of the two regions which result from it has its homologue in the development of the crayfish, though its precocious appearance there has led to its being misinterpreted as gastrular. It is evident, the author concludes, that an acquaintance with the development of Asellus is necessary to an understanding of the other forms ; and a full comparison is promised. Freshwater Copepoda and Cladocera of Portugal.* — MM. J. De Guerne and J. Richard give a first list of these Crustacea. They enumerate in all 25 species, all of which are known and most of which are common in Europe. This appears to be the first list which has been given of these Crustacea from the fresh waters of Portugal. Annulata. Epigamy and Schizogamy.f — M. A. Malaquin discusses these two phenomena in Annelids. In epigamy the whole sexual individual is affected, the eyes increase in size, the notopodia of the median and pos- terior regions change and acquire natatory setae. Such changes, first observed in Nereidae, are also known in Syllidae and Hesionidae. In schizogamy, only a part of the animal acquires the characters of sexuality, separating off and swimming freely. The part may acquire a differen- tiated head with appendages and large eyes, but it has no mouth, and is wholly reproductive. Various aspects of this schizogamy (which must be carefully distinguished from schizogenesis, are illustrated by Syllis (// aplosyllis) hamata Clp., Trypanosyllis , S. prolifer a Krohn, S. arnica Qtrfs., and S. ( Typosyllis ) hyalina. What the author particularly insists on is that in Autolytus longeferiens St. Joseph and Exogone gemmifera Pag. both epigamy and schizogamy are included in one life-cycle. Combined Nucleoli.f — M. A. Michel treats particularly of combined nucleoli, as observed in the eggs of the Annelids. These bodies have been found in the tissues of various animals, but the author has confined his researches to the eggs of Nephtliys and Spiophanes. The bodies in question contain one part which is solely granular, and stains with safranin more than the rest of the egg, and another clear refractive * Bull. Soc. Zool. France, xxi. (189G) pp. 157-9. t Zool. Anzeig., xix. (1896) pp. 420-3. X Coniptes Rendus, cxxiii. (1896) pp. 903-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 37 part, almost oily in appearance, which does not stain. The author gives some details as to his observations, and remarks that, as to the origin of these nucleoli, no one has been able to give a definite account of how they became connected. Lymphatic Glands of Nereids.* — Prof. A. Ko wale vsky demonstrated both by sections and by injections of carmine, &c. that a pair of lymphatic or phagocytic glands occur regularly in each segment (of Nereis cultri - fera and other forms) just above the parapodia. He responds to Mr. E J. Goodrich, who regarded the alleged organs as accidental agglomera- tions of leucocytes. Earthworms from Celebes.f — Dr. W. B. Benham remarks that, al- though a considerable number of species of Perichseta have been de- scribed from the Malay Archipelago, none seem to have been collected on the island of Celebes or from Jampea, which is due south of it. Mr. H. Everett made a collection of twelve worms, which fall at least into six groups, none of which agree with any species hitherto known. We are glad to add that Dr. Benham has appended to his description of the anatomy of the individual a summary of what he regards as the charac- teristic features in the form of a diagnosis. He, like others, has much felt the absence of such a brief resume in many instances, while reading through the literature of the genus. N emat ohelminthes . Filaria nocturna.j — Mr. F. Henry reports an interesting case of indigenous parasitic cbyluria with Filaria nocturna in the blood. This is the first case that has been observed in Philadelphia, and was intro- duced from the south. The patient; came under treatment to be delivered of a child, who was born healthy. Before delivery, she had complained of pains in the region of the kidneys. The urine was milky, and contains signs of albumen, but no sugar. On microscopic examina- tion of the blood, the author discovered in it Filaria sanguinis. At first about five Filarise could be seen in the preparation, but later on they were more numerous. They were only found in the blood at night. The author made use of several leeches to see whether they would serve as intermediate hosts. The parasite only lived for three or four days in the leech and then died. In the course of six weeks the blood and the urine were repeatedly examined, and during this time Filaria nocturna was always found in the blood, and often in the urine. The parasite was not killed either by treatment with chinin, thymol, or metbylen-blue. The use of the last reagent caused colouring of the blood-serum, and of the parasite itself, while the stools and urine of the patient were coloured, as were also the stools of the child whom the patient suckled. According to the author’s observations, Filaria nocturna rebelled against all medicines that were tried. The parasite appears also to have a great power of withstanding cold. It lives for ten days in * CR. Congr. Internal Zoel. Leyde, 1896, pp. 526-30 (1 pi.). f Ann. Mag. Nat. Hist., xviii. (1896) pp. 429-48 (2 pis.). X Med. News, 2nd May, 1896. See Centralbl. f. Bakteriol. u. Parasitenk., lta Abt., xx. (1896) pp. 619-20. 38 SUMMARY OF CURRENT RESEARCHES RELATING TO a cold chamber. The author recommends the careful filtration of water, as he thinks it possible the parasite may be introduced by this fluid. Platyhelminthes. New Freshwater Nemertean.* — Dr. T. H. Montgomery jun. de- scribes a freshwater Nemertean from Pennsylvania, to which he gives the name of Stichostemma asensoriatum. This barbarous specific name is, we are told, given in consequence of absence of the supraoral sense-pit, though we don’t think that this is any excuse. A few details are given as to the characters of these worms, which are remarkable for having been found in a stream less than a yard in breadth and at no place more than a foot in depth. Most freshwater Nemerteans, it will be remembered, have been found in larger streams and rivers. Only three other Nemerteans are known from the fresh waters of North America. Turbellaria of the Michigan State Fish Commission. -f — Mr. Yd. M‘M. Woodworth has a short report on the Turbellaria collected by the Michigan State Fish Commission, during the summers of 1893 and 1894. The collections, though few in number, contributed to the Tur- bellarian fauna of the United States four new species. The author points out that it is a matter of regret that in many cases new species have to be described from alcoholic material, for the action of killing and preserving reagents tends to destroy or bleach the pigments, and alter the shades of the animal, so that descriptions of this kind make sub- sequent identification difficult. The descriptions of the worms contain no point of any general interest. Haplodiscus.J — -Herr H. Sabussow has studied some specimens of Haplodiscus obtained from Naples, which are not only the first recorded European forms of this pelagic Atlantic genus, but represent a new species, H. Ussowii. The body is flat and lens-like, with almost circular outline; the dimensions are *8 mm. in length, *86 mm. in breadth, 160 /x in height ; the anterior end is quite rounded, the posterior end invaginate ; the mouth lies in the second third of the body ; pharynx and frontal organ are absent ; the brain lies far forward ; otocysts occur ; the ovaries form two compact ventral strands connected in the middle line ; the testis is unpaired and dorsal ; there are no vasa deferentia, but there is a seminal vesicle and a tubular penis, covered with small warts. The new species is nearest H. orbicularis. Anatomy and Histology of Amphistomida0.§ — Dr. B. Otto has had the opportunity of investigating seven species of this group belonging to the genera GastrocTiscus, Ampliistomum , and Gastrothjlax. In the first part of his work the author deals with the anatomy of these forms, while in the second part he treats the organs from the standpoint of compara- tive histology. He regards the cuticle of these worms, which ordinarily consists of two layers, as an excretory product of the parenchyma. There are no tegumentary glands. The musculature of this group does not differ from that of other Trematodes. Especial attention appears to * Zool. Anzeig., xix. (1896) pp. 436-8. t Bull. Mus. Comp. Zool., xxix. (1896) pp. 239-43 (1 ph). J MT. Zool. Stat. Neapel, xii. (1896) pp. 353-80 (2 pis.). § See Zool. Centralbl., iii. (1896) pp. 769-71. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 39 liave been paid to tbe nervous system. Throughout the group the generative apparatus appears to be similarly formed. All species have two testes, the number of lobes of which increases with age. Aspidogaster conchicola.* — Dr. J. Stafford gives a lengthy memoir on the anatomical structure of this worm which, as he rightly remarks, has already been the subject of frequent observation. Its organs, how- ever, have not been subjected to the methods of modern research. The author does not provide any summary of his conclusions, and it is im- possible for us to do more than indicate the details on which he reports. The parenchyma is the name applied to a mass of cells placed directly under the subcuticular system of muscles hitherto not observed in this genus, though frequently described under various designations in others. It seems to have had, indeed, more than a dozen names already. It appears to be the site of active reproducing cells from which modification takes place in two directions. The elements towards the cuticle remain mostly small and indefinite, while those towards the centre of the animal increase rapidly in size, and are transformed into glands, &c. The anterior end is called a mouth-sucker, although it is recognised that it is a much less specialised organ than the mouth-sucker of nearly all Trematodes. It is likely that its form in the adult has more relation to the needs of nourishment than to those of locomotion. The author describes the difficulty that he had in recognising the presence of slime- glands. The parasites themselves are to some extent bathed in their own secretion, and must carry some of it into their intestines. As may be supposed, the author’s account of the excretory system extends over a number of pages. He is not yet able to give an approximately com- plete description of the nervous system. Hew Species of Bilharzia.j — Sigg. C. Parona and V. Ariola report the discovery of a new species of this parasite in the blood of the black- headed gull ( [Lams melanocephalus'). They call it B. Icowalevslcii. The male reaches the length of 14 mm. ; the surface of the body is smooth, and there are no spines or tubercles. The gynaecophoral canal begins just behind the ventral sucker, and extends as far as the caudal end. The intestine is forked in front of this sucker, and does not unite again into an unpaired canal as in B. hsematobia, but the arms of the intestine run separately to the hinder end, although they cross one another re- peatedly. Distoma Opisthobrias.j; — Herr A. Lutz describes a new species of fluke from a Brazilian Opossum. It belongs to the gronp in which the genital pore lies in the hinder end of the body, but is not terminal. Its close ally is a fluke found in the common European Hedgehog. It is probable that the intermediate host is some land snail. Distomum felinum.§ — Prof. P. Sonsino twice found Distomum felinum in dogs, and once in a cat, who had bitten a girl without obvious cause, * Zool. JB. (Abth. Anat.), ix. (1896) pp. 477-542 (6 pis.). f Boll. Mus. Zool. Genova, 1896, No. xlv. See Centralbl. f. Bakteriol. u. Parasi- tenk., lte Abt., xx. (1896) p. 620. t Revista Mus. Paulista, i. (1895) pp. 180-88 (1 pi.). See Centralbl. f. Bak- teriol. u. Parasitenk., lte Abt., xx. (1896) p. 623. § Gaz. d. Ospedali e d. Cliniche, xvi. (1895). See Centralbl. f. Bakteriol. u. Para- sitenk., lte Abt., xx. (1896) p. 709. 40 SUMMARY OF CURRENT RESEARCHES RELATING TO and had, therefore, been suspected of rabies and killed. Large numbers of Distoma were found in the liver. The possibility of human infection is pointed out, and the suggestion made that in cases of Cirrhosis hepatica careful search should be made, more especially as Winogradoff has already shown that in Siberia, D. felinum occurs in man, and causes Cirrhosis parasitaria hepatos. The author also mentions some recent observations on D. Westermanni. His chief object appears to be to point out the danger of human infection from the diffusion of these parasites. Hymenolepis diminuta Rudolphi found in Man.* — Prof. P. S. do Magalhaes records a second instance of the occurrence of Hymenolepis diminuta Rudolphi ( Taenia flavopunctata Weinland) in man. The patient was a mulatto, twenty months old, living at Rio de Janeiro. The worm passed was 18 cm. long and 3J mm. broad. The broadest part was some 18-20 links before the posterior end, the links there being 0*3 mm. long. Altogether, about 1300 links were counted. The head was 0 '56-06 mm. broad, and was furnished with four suckers, close to the rostellum. The neck was short and 0*34 mm. broad. The genital pores were on one side. The eggs were round, with a diameter of 59*5 p, and that of the embryos was about 34 p. The last eight links- of the chain, which were quite empty, were 0 • 6 mm. long and 1 * 5 mm. broad. The case is recorded on account of the rarity of this Tsenia as a human parasite. Tsenia (Hymenolepis) nana v. Siebold and Taenia murina Duj.f — Prof. O. von Linstow is of opinion that Tsenia nana and T. murina are distinct species. He relies on differences of size and anatomy. The number, shape, and size of the booklets are different in both examples. The cortical layer is more strongly developed in the human tapeworm than in the parasite of the rat. On the other hand,. T. murina has larger testes than T. nana. Other differences occur in the disposition of the receptaculum seminis in the ripe proglottides, and in the structure of the eggs. In T. nana the ova are spherical and double shelled, and on the inner investment are two thread-like processes. The ova of T. murina are triple shelled and elliptical. The inner coat has a knob-like process at both poles. Tsenia nana has a universal dis- tribution, while the allied cestode of the rat and mouse has hitherto been found only in Europe. The hosts of both worms are different, and whether the direct development of T. murina occurs also in T. nana of man, the future can only decide. Cysticerci of Bothriocephalns latus.J — Mr. A. E. von Schroeder gives, in Russian, an account of his studies on the broad-worm in Russian fishes. Out of 80 two-year-old perches examined only 28 were infected, and these only in very small quantities. It appears likely that the fish becomes directly, and at various ages, again and again infected with the free-swimming larvae of this parasite. The spring and summer months appear to be those in which infection most frequently occurs. * Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1806) pp. 673-4. f Reference given is 12 pp. and 8 figs. See Centralbl. f. Bakteriol. u. Parasitenk , lte Abt., xx. (1896) p. 708. t Prakt. Medizin, iii. (1896) Beil. See Centralbl. f. Bakteriol. u. Parasitenk.,. lte Abt., xx. (1896) p. 621. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 41 New Human Tapeworm.* — Mr. IT. B. Ward has a preliminary de- scription of a new human Tsenia, of which two examples have been found. It is proposed to call the new species T. confusa. The terminal joints are 27-35 mm. long, and 3 * 5-5 mm. broad. This length is, of course, considerably greater than that of the joints of the two common tapeworms which infest mankind. The scolex has four suckers and a retractile rostellum, which has six or seven closely set rows of small hooks. It is to be hoped that other practitioners will keep an eye on this parasite, and give us a fuller knowledge of it than we have at present. Remarkable Pseudhelminth.f — M. A. Bavay gives an account of a remarkable form which was found in the fasces of a patient. The bodies found had the form of brown, jointed ribbons, wider at one end than the other, which became almost transparent. Each ring, or what appeared to be a ring, carried a pair of curved short feet. The only questions that suggested themselves were — are these marine annelids, or are they myriopods? They were, of course, nothing of the kind. By a happy thought the author recalled the relatively large lingual ribbon of the limpet, and this is what they were ; the patient had eaten limpets and digested their flesh, but the horny and spiral radulse had merely become unrolled. Rotatoria. Notommata wernecki. J — Prof. W. Rothert describes this form, which makes galls on VaucJieria- filaments, as has been known since the beginning of the century. To Balbiani’s careful description (1878) the author has some results to add. The masticatory apparatus is not reduced, and the unci may be seen protruded from the mouth. Entrance into the filament seems to be effected by the growing point. The parasite eats not only the colourless protoplasm, but also fat-drops and chlorophyll grains. The females cannot complete their development outside of the galls. As Balbiani observed, the same female may lay summer and winter ova. The winter ova have a delicate external and a firmer internal envelope, the latter formed some time after laying and alone persisting during the resting period. Only a few winter ova are produced, but over sixty summer ova may be laid by one female. In favourable condi- tions, not wholly dependent on temperature, summer ova as well as winter ova may be produced in late autumn and winter. In winter ova, segmentation occurs immediately after laying ; before it stops the inner envelope is formed ; during the resting period the egg contains a fairly well-developed embryo. This is probably true of other winter ova of Rotifers. Prof. Rothert was fortunate enough to find the males. They are remarkable in having a normal masticating- apparatus, though the alimentary canal is rudimentary. They thus approach Seisonidm. Female and male summer ova are laid normally by the same female, the former usually predominating; and the same is probably true of the winter ova. The parthenogenetic development of the male summer ova is quite certain, but it is not likely that all summer ova are unfertilised. * West. Med. Keview, i. (1896) pp. 35-6 (2 figs.). t Bull. Soc. Zool. Franco, xxi. (1896) pp. 162-3. % Zool. Jahrb. (Abth. Syst.), ix. (1896) pp. 672-713 (4 figs.). 42 SUMMARY OF CURRENT RESEARCHES RELATING TO Incertse Sedis. Structure of Actinotrocha.* — Mr. A. T. Masterman has a memoir on the structure of Actinotrocha , considered in relation to the suggested chordate affinities of Phoronis. He points out the close harmony of structure which is to he found between the larval forms of Actinotrocha and Tornaria. The chief of these are the following : — A much overhanging preoral lobe and, in some cases, two eye-spots ; a preoral ciliated ring ; a postoral ring ; a circumanal ring of cilia ; mesoderm forming five coelomic pouches, one preoral and two pairs postoral. Mr. Masterman thinks that the study of the structure of Phoronis and of its larval form Actinotrocha entirely points to the close alliance of the genus to the members of the group of the Hemichordata, and Balanoglossus in parti- cular. The present structure of Phoronis points to a marked degenera- tion, due to a sedentary life, for the highest stage of the organs is reached in Actinotrocha just before the metamorphosis, which results in the transformation to the adult condition. In the next place, the struc- ture [of Actinotrocha conforms to the hemichordate type extremely closely, even to minute particulars. As a general result of his work, the author proposes a further arrangement of the Chordata, forming the grouj) Diplochorda for Phoronis. He appends the following view : — Chordata. A. Trimetamera. 1. Diplochorda. Phoronis. 2. Hemichorda. Balanoglossus , Cephalodiscus} % Bhabdopleura. B. Polymetamera. 3. Urochorda. 4. Cephalochorda. 5. Holochorda. Echinoderma. Function of Polian Vesicles in Sea-TJrchin.j — Herr J. vonUexkiill uses the term “ Polian vesicles ” in the sense in which Delle Chiaje used it, in reference to the five interradial bladders ( Zahnblasen ) which lie above the lantern. The history of the term and of what has been said and figured in regard to the organs in question is sketched in an instruc- tive, if somewhat humiliating, fashion. The only figure which the author finds to commend is that given by Romanes and Ewart. The radial bladders ( Gabelblasen ) between the interradials ( Zahnblasen ) have suffered similar maltreatment. Both Gabelblasen and Zahnblasen are diverticula of the membrana limitans lanternae. Uexkiiirs investi- gation concerns their function. After discussing the conditions of pressure within Sphser echinus, he shows that the bladders are not to be interpreted as otolithic, nor as locomotor. The “ compass ” muscuHture serves solely to regulate the pressure within the bladder system of the membrana limitans ; the regulated changes of pressure subserve respira- tion and the masticating movements. Increase of pressure within the vesicular space serves to protrude the oesophageal papillae ; the changes * Proc. Roy. Soc. Edinburgh, xxi. (1896) pp. 129-37 (4 figs.). f MT. Zool. Stat. Neapel, xii. (1896) pp. 463-76 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 43 of pressure serve to fill and empty tlie gills. The compass muscles are inspiratory, the Gabel-muscles expiratory. Apart from its discussion of the bladder system, the paper includes some interesting physiological observations, e.g. on the sensitiveness of sea-urchins to carbonic acid gas. Elasipoda of the ‘ Travaiileur ’ and ‘ Talisman.’ * * * § — M. E. Perrier has a preliminary report on the Elasipoda collected by these two vessels in 1882 and 1883. Among the deep-sea forms the Holothurians were represented by more than 700 individuals. Of these no less than 354 belonged to the Elasipoda. Altogether there were 9 genera, 2 of which are new, and 14 species, 10 of which are new. The new genera are called Periamma and Tutela, both belonging to the tribe Elpidiinae. The former has on its dorsal surface a transverse row of four papillae, while the latter has three small dorsal papillee in each ray, which are often hardly visible. Holothurians of the £ Princess Alice.’ t — M. E. Herouard gives an account of Holothurians collected by the Prince of Monaco in the Atlantic. Only 14 species were collected, of which 3 are new. Coelentera. Extra-European Hy droids, if — Mr. Elof Jaderholm has a report on the extra-European Hydroids contained in the Zoological Museum of the University of Upsala. In addition to some new species, he describes as new genera Spongocladium and Antennellopsis. The former belongs to the family Solanderiidoe ; there are no signs of hydrophores, and the polypes arise directly from the intermediate space of the reticulate skeleton ; the skeleton itself is flexible. S. Iseve is a new species from Japan. Antennellopsis is a form likewise from Japan, whose exact posi- tion is somewhat difficult to define, as it has a distinct resemblance to the Plumulariidae on the one hand, and the Aglaopheniidm on the other. The difficulties of determination are increased by the fact that all speci- mens at present observed are sterile. Porifera. Hatural Classification of Asconidse.§ — Mr. E. A. Minchin has a preliminary notice on these calcareous sponges, on the study of which he has been engaged for some years past. He begins with a protest against a notion which has been prevalent since Haeckel’s writings, and due largely to them, that the form of Ascon colony is useless for purposes of generic or specific determination. Indeed, Mr. Minchin thinks that most writers on these sponges have been acquainted only with preserved specimens. It is his experience that almost any species of Ascon can be identified at sight when one is acquainted with it, and that the mode of growth of the colony is a character of great generic value. It is true, he adds, that “ it is almost hopeless to recognise an Ascon by its exterior from the figures given by Haeckel, but that is hardly the fault of the * Comptes Rendus, cxxiii. (1896) pp. 900-3. t Bull. Soc. Zool. France, xxi. (1896) pp. 163-8 (2 figs.). t Bih. K. Svenska Yet. Acad. Handlgr., xxi. iv. No. 6 (1896) 20 pp. and 2 pla. § Ann. Mag. Nat. Hist., xviii. (1896) pp. 349-62. 44 SUMMARY OF CURRENT RESEARCHES RELATING TO Ascons” The author recognises three genera : — Clcitlirina with nine spe- cies, Leucosolenia with four species, and Ascandra with one. There re- main many other known species of Ascons to which this classification must be fitted if it is to be rendered complete. The relations of the genera are indicated by the genealogical tree which we reproduce below : — Calcareous Sponges from Ternate.* — Herr L. Breitfuss has a pre liminary communication on the calcareous sponges collected at Ternate by Prof. Kukenthal. The material is said to have been well preserved, and the ten examples collected belong to six species and five genera, none of which appear to be new. New Calcareous Sponge.f — Herr L. Breitfuss has a short prelimi- nary contribution on the new heteroccelous calcareous sponge which he calls Amphoriscus semoni. It has the form of a delicate silvery cylin- drical tube, attached by means of a thin curved stalk to the shell of Avicula. Though found at Amboina, it calls to mind two Adriatic spe- cies, from which, however, it is to be distinguished by the character of its spicules. Protozoa. Nucleus of Protozoa.J — Miss M. Greenwood has published the first part of a study on structural changes in the resting nuclei of Protozoa. Sbe now treats of the macronucleus of Carchesium polypinnm. This creature was selected on account of the size and distinctness of its nuclear constituents, and from the fact that long use has made the author familiar with the structure and habits of the animal. This macronucleus has a strong affinity for stains, and consists in its maturity of four structural elements : — (1) The protomacrosomes, (2) the protomicrosomes, (3) the nucleochyme, and (4) the nuclear membrane. The first of these con- stituents are complex mobile bodies, especially prominent in the majority of stained specimens. Their complex character and action are suggested by, firstly, their reaction with dyes ; for, staining selectively with eosin, they may also colour deeply with methylen blue. In the second place, * Zool. Anzeig., xix. (1S9G) pp. 433-5. f Tom. cit., pp. 435-6. % Journ. of Physiol., xx. (18J6) pp. 427-54 (l pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 45 they have a remarkable capacity for vacuolation. The protomicrosomes are less strongly chromatophilous than the macrosomes, but their affinities are distinctively for basic dyes. The structural constituents of the ma- cronucleus are free from inorganic iron, but iron maybe unmasked in the nucleus by appropriate treatment with acid. The variation which has been observed in nuclear structure may be correlated in part with the condition of nutrition of Carchesium ; thus specimens nourished on in- termittent bacterial diet have scattered macrosomes of medium size ; with abundant artificial nourishment the macrosomes increase in size. The association of nuclear change with varying nutrition is more than coincidental, as may be seen, not only by experimental results repeatedly obtained, but by examination of senile or moribund nuclei on the one hand, and of the macrosomes during reproduction on the other. Miss Greenwood looks forward to the results of histological work which shall correspond to and complement the suggestive experiments of Yerworn — to study of structural change bound up with those demands on nuclear activity which he has associated with the reconstitution of divided cells. Protozoa of Lake Michigan.* — Mr. C. A. Kofoid has a report upon the Protozoa observed in Lake Michigan and the neighbouring inland lakes during the summer of 1895. The present paper makes no pre- tensions to completeness, being merely a compilation from the daily record of work ; it gives the distribution and relative abundance of such species as were identified during the six weeks the author studied at the laboratory. The list records 81 forms, this number being made up of 76 species and 5 varieties. They were thus distributed among the different groups : — Kliizopoda 22, Heliozoa 5, Mastigophora 20, and Infusoria 34. Hygienic Importance of Parasitic Vorticellse.! — Herr G. Lindner makes a new communication relative to Vorticella ascoidea. It appears that he has succeeded in transferring stalked to unstalked Vorticellse, and observed their further development. In the unstalked Vorticellse the author sees the direct or indirect cause of disease to animal organisms, and several cases are enumerated. Among these was a malady of ty- phoid type affecting two labourers, in whose stools Vorticellse were found. The author has found Vorticellse in the blood of dogs which had been fed with Vorticella. He is of opinion that Miescher’s tubes are Vorticella cysts. In eczema of the scalp (from which he suffers himself ), the author has found Vorticellse. The cause of muscle poison- ing is also assigned to Vorticellse , which convert the albumen into tox- albumen. From sarcoma, carcinoma, and cowpox-lymph the author has bred cercomonads, but failed to reproduce them from their encysted stage. ew Amoeboid Rhizopod.* — Herren E. v. Leyden and F. Schaudinn have found in the ascitic fluid of living men an amoeboid Rhizopod, * Bull. Michigan Fish Coram., No. 6, Appendix ii. pp. 76-84. t Deutsche Medizinal-Zeitung, 1896, No. 65. See Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 705-6. x Situngsber. Konigl. Preuss. Akad. d. Wiss. zu Berlin, xxxix. (1896) p. 13 (1 ph). See Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 465-6. 43 SUMMARY OF CURRENT RESEARCHES RELATING TO Leydenia gemmipara Schaudinn. The organisms are round or poly- morphic, with radiating or hair-like processes. They are considerably larger than leucocytes, and contain fat-globules and pigment. Repro- duction took place by budding and by fission. The specimens were obtained by centrifuging the exudate, which was examined at 25° and on the hot- stage. iEtiology of Texas Fever.* — Herren Weisser and A. Maassen ex- amined blood from the kidneys of oxen imported from America to Hamburg. No bacteria were found, but within the red corpuscles peculiar bodies were observed. Transfer and cultivation experiments were negative. The red corpuscles contained spherical bodies — usually single, occasionally in pairs, and rarely more than two. Not infre- quently the parasites were found free in the plasma. As a rule, the parasites were spherical, but sometimes elongated and pyriform. They stained readily, but not equally, with anilin dyes. The parasites were also met with in the blood and juices of spleen, liver, heart, and lym- phatic glands. Thus the observations of the authors confirm those of Smith and Kilborne, who first described the parasite of Texas fever under the name of Pyrosoma bigeminum. Sarcosporidia in Muscle - Fibres of the Tongue of Cattle and Sheep. | — Prof. Fr. Sanfelice found in sections of tongues of cattle and sheep almost invariably sarcosporidian tubes which, under a power of 15-20, are seen as small white spots. As a rule, fully developed tubes, occupying the half to the whole thickness of the muscle fibres, pre- dominate, the early stages of development being of rare occurrence. The larger tubes are invested in a very delicate structureless membrane and contain sickle-shaped bodies composed of two substances, one of which has an irregular distribution and the other is highly refracting. In stained preparations, uncoloured places are brought out, but no nuclei. The youngest stage of development consists of a protoplasmic mass without structure. Infection continues by bursting of the ripe tubes, the escape of the sickle-shaped bodies, and the invasion of fresh muscle-fibres. Herein they form new tubes, after enlargement and fis- sion. As a further stage of development, the author found protoplasmic masses containing nuclei, which, as they increased in size, became oval, and were finally converted into sickle-shaped bodies. * Arb. a. d. Kaiserl. G-esundheitsamte, xi. p. 411. See Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 704-5. f Zeitschr. f. Hygiene u. Infektionskr., xx. p. 13. See Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) p. 754. ZOOLOGY AND BOTANY* MICROSCOPY, ETC. 47 BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-Structure and Protoplasm. Respiratory Function of the Nucleus.* — In further notes on the process of nuclear division, M. C. Degagny lays stress on the fact that (in Spirogyra and Liliurn candidum) during the formation of the nuclear plate, the length of the spindle is reduced by one-half. The energy re- quired for this contraction has its origin in the respiration of the cell, the seat of this respiration being the outer threads of the spindle and the adjacent parts of the cytoplasm. The filaments do not merely contract, but become at the same time rigid and tetanised. They subsequently lose their rigidity, and the phenomena attending these processes are de- scribed in great detail. The principal function of the nucleus during division appears to be to prepare a substance destined for respiration ; this protoplasmic substance, capable of easy digestion and of contracting while respiring, is furnished by the fine filaments of the spindle. In Lilium candidum, owing to the enormous mass of protoplasm which fills the embryo-sac, respiration is greatly reduced in the central part. In Spirogyra, on the other hand, where the nucleus is in immediate relation with the external medium, it is much more evident. Vegetable Cytology .f — In a new work on the morphology and physio- logy of the nucleus in plants, Prof. A. Zimmermann gives a summary of all the more important recent observations in this subject. The book is divided into three main parts ; the first dealing with technique, and with the chemistry and physiology of the nucleus in general ; the second, with the structure and behaviour of the nucleus in the different groups of the vegetable kingdom, including its history in fertilisation and em- bryogeny ; while the third part consists of a copious bibliography. Prof. J. B. Farmer J gives an account of the more important ad- vances recently made in the study of Vegetable Cytology. He lays stress on the fact that the two methods — microchemical and staining — should both be employed. While the staining exhibits more or less completely the structural arrangement of the substances present, the microchemical method not only indicates some at least of the important differences which exist between the different structures revealed by the action of staining, but it teaches us that certain of these same structures are by no means so homogeneous in their nature as one might be led to suppose from the evidence derived from staining alone. * Bull. Soc. Bot. France, xliii. (1896) pp. 310-4, 332-16. Cf. this Journal, 1896, p. 535. f ‘ Die Morph, u. Phys. d. pflanzischen Zell-kernes,’ Jena, 1896, 188 pp. See Nature, lv. (1896) p. 147. X Science Progress, v. (1896) pp. 22-37 ; i. (1897) pp. 141-66. 48 SUMMARY OF CURRENT RESEARCHES RELATING TO (2) Other Cell-Contents (including: Secretions}. Spectrum of Chlorophyll.* * * § — M. A. Etarcl describes in detail the spectrum of several different kinds of chlorophyll. He classifies the various kinds of chlorophyll in two groups, to which he gives the formulae C28H45N04 and C34H53N012. These are found in different plants, and have different spectra. Artificial Starch. — Dr. 0. Biitschli f claims to have produced artifi- cially sphaerocrystals of starch by the very slow evaporation of a mixture of gelatin and an aqueous solution of starch, and maintains his previous view that starch and inulin have both a honeycomb structure. These researches are subjected to a very unfavourable criticism by Herr A. Meyer . J Colouring-Matter of the Aril of Celastrus.§ — Dr. Ida A. Keller finds the colouring-matter of the aril of Celastrus scandens to be a sub- stance resembling carotin, but differing from it in not being precipitated by alcohol after dissolving in carbon bisulphide. Reserve Food-Materials. || — Prof. J. R. Green gives the results of recent investigations on the mode of formation and the function of the various food-materials of plants. With regard to the alkaloids, he arrives at the conclusion that the greater number of them, and probably all, must be regarded not as reserve-materials, but as bye-products or ex- creta, appearing coincidently with the active metabolic processes of the growing plant. (3) Structure of Tissues. Wood of the Oak.^i — Herr P. Metzger states that the duramen and alburnum of the oak contain the same tannin, with the approximate formula C15H16On, that of the bark being different ; they are both glucosides. The alburnum, duramen, and bark contain the same oil, be- longing to the series of palmitic, stearic, carotic, and oleic acids ; no cholesterin or wax was detected. Oxalic, malic, and tartaric acids were found in all three tissues ; also glucose and cane-sugar, but starch only in the duramen and alburnum. Secreting Pockets of the Myoporacese.** — In contrast to the state- ments of previous observers, M. J. Briquet has established that these structures are of schizo-lysigenous origin, a mode of formation of similar bodies which seems to be very widely distributed. Their first origin is schizogenous ; but the mode of escape of the oil into the central cavity and the subsequent processes must be termed lysigenous. The site of formation of the oil is always the cell-walls which are in process of gelification ; and the nucleus, wdiicli is always situated near the walls which bound the central cavity, appears to take part in the process. * Comptes Rendus, cxxiii. (1896) pp. 824-8 (1 fig.). t Ber. Versamml. Deutsch. Naturf. u. Aerzte, 1896, Bot. Sect. See Bot. Cen- tralbl., lxviii. (1896) p. 213. X Bot. Ztg., liv. (1896) 2te Abt , pp. 328-35. § Proc. Acad. Nat. Sci. Philadelphia, 1896, pp. 212-6 (1 fig.). II Science Progress, v. (1896) pp. 60-76. ‘Beitr. z. cliem. Charakt. d. Holzkorpers der Eiclie,’ Heilbronn, 1896, 34 pp. ,See Bot. Centralbl., lxviii. (1896) p. 48. ** Comptes Rendus, cxxiii. (1896) pp. 515-7. Cf. this Journal, 1895, p. 190. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 49 Structure of Trigoniaceae and Chailletiaceae.* — An examination of a number of species belonging to these two small orders of Thalamitlorae leads M. F. Barth to the conclusion that they are nearly related to one another, and that the Trigoniaceae should be separated from the Vochy- siaceae. The epiphyllous inflorescence of certain Chailletiaceae results from the fact that a bud-bundle, instead of detaching itself from the foliar bundle in the stem, is drawn up to a certain height along with the latter. “ (rommose bacillaire ” of the Vine.f — In opposition to the view of Prillieux and others, Herr E. Rathay maintains that this disease is not due directly to the attacks of a bacillus The gum is formed in the ordinary way for the protection of a part injured by a wound or by un- favourable vital conditions. (4) Structure of Organs. Importance of Anatomical Characters in Classification.! — M. P. Parmenticr insists on the importance of using characters derived from the internal anatomy, as well as morphological characters, for determining both the bounds of critical species, and the position of difficult genera. A number of illustrations of both kinds are given. It is shown that, on anatomical grounds, Trctpci must be placed among the Ilalorageae and not among the (Enotliereae, and that the Eupeteleae have no genetic con- nection with the Magnoliaceae. The most important anatomical characters are ; in the leaf : — the general presence or absence of crystals, especially in the epiderra ; the pattern of the cell-walls of the cuticle ; a single or multiple epiderm ; the presence or absence of hypodcrm ; the centric, sub-centric, or bifacial structure of the mesophyll ; the presence or absence of vesicular reservoirs, of fibres running through the mesophyll, and of sclerified cells ; and the mode of increase and localisation of the latter. In the stem : — the general plan of the vascular bundles ; the presence or absence of periderm, of mechanical fibres, of sclerified cells, and of crystals, and the localisation of these various elements ; the form and orientation of the cells of the conjunctive parenchyme, &c. Flower of Canna.§ — Prof. L. H. Bailey calls attention to the pre- vailing want of symmetry in the Scitamineae. The reduction in the number of stamens is carried to excess in the Zingibereae, where there is only one, and still more in the Canneae, where the stamen is represented by what is apparently a single loculus, the other loculus being developed into a foliaceous organ, and the remaining five stamens into petaloid staminodes. Stigma and Pollen of Ariseema.|j — Mr. W. W. Rowlee describes the structure of the stigma and pollen in Arissema triphyllum and A. Dracunculus (Araceae) ; the principal peculiarity being that the stigmatic papillae are continued down the inner surface of the open stigmatic tube, * Bull. Herb. Boissier, iii. (1896) pp. 481-520 (33 figs.). f JB. K. K. Oenol. u. Poinol. Lehranslalt Klosterneuburg, 1896. See Bot. Ceil- tralbl., Ixviii. (1896) p. 54. Cf. this Journal, 1896, p. 100. X Ann. Sci. Nat. (Bot.), ii. (1896) pp. 1-36. § Lot. Gazette, xxii. (1896) pp. 222-3. j| Bull. Torrev Bot. Club, xxiii. (1896) pp. 369-70 (2 pis.). 1897 E 50 SUMMARY OF CURRENT RESEARCHES RELATING TO and form a stigma-like tuft at tlie summit of the ovary, close to the micropyle of the erect ovule. Compound Ovaries.* * * § — Prof. C. E. Bessey discusses the origin of the compound ovary, which he considers as differing in different cases. Apocarpous plants he regards as lower than syncarpous. Ovaries may be primitively simple, or may have become simplified from a more com- plex structure, as in the case of grasses and sedges. The Amentiferse, notwithstanding their apparently simple floral structure, are not to he regarded as among the lowest of the dicotyledons. Fruit of Phoenix melanocarpa.j — M. A. Girard describes in detail the composition of the fruit of a very remarkable date-palm, grown near Nice, which ripens its fruit in April, instead of in July, as is the case with the African date-palm. The chief chemical peculiarities are that the saccharose is entirely replaced by levulose, and the complete absence of acids, and of the tannin group of substances. Symmetry of the Axis.j; — M. A. Chatin lays stress on characters derived from the structure and origin of the roots as indicating the relationship of the primary divisions of the vegetable kingdom. In Dicotyledons there is always a true perennial descending axis originating from the embryo ; in Monocotyledons there is a system of primary roots, of temporary duration, succeeded by adventitious roots ; in Acotyledons, all the roots are adventitious. The root is fibrovascular in the Dico- tyledons, Monocotyledons, and higher Acotyledons ; cellular in the lower Acotyledons. The Dicotyledons alone produce from their primary descending axis secondary roots arranged symmetrically, comparable to the arrangement of leaves on the stem. Stem and Leaf of Phyllanthese.§ — Dr. H. Rothdausclier goes into great detail respecting the structure of the leaf and axis in the various genera belonging to this family of Euphorbiacese, excluding the Euphyl- lan these. Among the more general characters may be mentioned the absence of latex-tubes, the absence of glandular hairs, with the exception of peltate hairs in one genus, the occurrence of companion-cells parallel to the fissure of the stomates, the comparative or complete absence of hairs, &c. Spines of the Aurantiace9e.|| — Sig. E. Migliorato discusses the anatomical nature of the spines in Citrus Aurantium and other species of the order. From the occasional occurrence of subtending bracts and from other characters, he concludes that they are of axial and not of foliar origin. Position of Leaves.1T — According to’ Mr. R. N. Day, the position of the leaf is the result of internal physiological, not of external mechanical forces. The predominating force is always the lieliotropic tendency. * Bot. Gazette, xxii. (1896) p. 224. f Comptes Rendus, cxxiii. (1896) pp. 720-4. % Bull. Soc. Bot. France, xliii. (1896) pp. 267-72. § Bot. Centralbl., lxviii. (1896) pp. 65-79, 97-108, 131-6, 161-9, 193-203, 248-53, 280-5, 305-15, 338-46, 385-93. || Nuov. Giorn. Bot. Ital., iii. (1896) pp. 436-8 (7 figs.), ^ Bot. Gazette, xxii. (1896) p. 222. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 51 Reaction of Leaves to continuous Rainfall.* — From a series of experiments made by Prof. D. T. MacDougal on tbe influence of a continuous rainfall upon leaves, be concludes that a direct effect on the structure of the leaf is produced, but that the nature of this change differs in different species. In addition to the hitherto recognised characters of adaptation to a heavy rainfall, the author adds an upwardly convex form of the lamina of the leaf. Petiole of Qnercus.f — M. F. Bosseboeuf distinguishes two distinct types in the petiole of different species of oak (1) At the base of the petiole the numerous isolated vascular bundles are arranged in a circular line, flattened above, or nearly triangular ; at the back of each of the bundles is a mass of sclerenchyme proceeding from the pericycle, with very strongly thickened walls. (2) The vascular bundles, also isolated at the base, but less numerous, soon unite to form a complete ring, flattened above, composed of a layer of internal xylem and one of phloem, and surrounded by the strongly thickened pericycle; this arrangement continues through the rest of the petiole and the median vein of the lamina ; there is never any internal arc. Varieties of each type are described ; and there are also intermediate forms, 0. Physiology. CP Reproduction and Embryology. Embryology of Balanophoracese.J — M. P. van Tieghem describes the structure of the male and female flowers in the different genera of this order. They may be classified under three families, characterised by the structure of the ovary in the female flower. In the first (Sarcophy- tideae) there are as many rudimentary and transitory ovules as there are earpels ; they are orthotropous, pendant, and basigamous, and the ovary is plurilocular, with axile placentation. In the second (Helosidese) there are no ovules, but only a placenta, enclosing as many endosperm mother- eells as there are carpels ; they are acrogamous, and the ovary is unilo- cular, with central placentation. In the third (Balanophorideae) there are neither ovules nor placenta ; but the monocarpellary ovary produces, beneath the epiderm of its base, a single acrogamous endosperm mother- cell. The order must be placed in the sub-class of Dicotyledons destitute of ovules, i.e. in the Loranthinese. Embryo-Sac of Succulent Plants.§ — A detailed study of the repro- ductive organs of succulent plants— especially the Cactacem, Mesem- bryanthemaceae, and Crassulaceae — leads M. E. d’Hubert to the conclusion that there are several features characteristic of this class of plants, though not absolutely confined to it. In the Cactaceae the ovules are so arranged as to fill up as completely as possible the cavity of the ovary ; they are amphitropous and bitegu- mented. The funicle is always strongly developed ; it is coiled round it, forming a complete envelope (the aril of Opuntia), and is loaded with starch ; it serves both to protect and to nourish the ovule. The embryo- sac is formed only at a late period, the axile hypodermal cell of the * Bot. Gazette, xxii. (1896) pp. 232-3. f Bull. Soc. Bot. France, xliii. (1896) pp. 260-6 (8 fio-s.Y % Tom. cit., pp. 295-310. § Ann. Sci. Nat. (Bot.), ii. (1896) pp. 37-128 (3 pis. and 61 figs.). 52 SUMMARY OF CURRENT RESEARCHES RELATING TO nucellus giving birtli to it directly. Starch is rapidly formed in the- embryo-sac, and plays a very important part in the nutrition Of the- embryo ; it is the antipodals that store it up for this purpose. The synergids take no part in this process ; the nucleus of one of these goes to meet the pollen-tube ; that of the other one drops to the neighbour- hood of the oosphere, and remains there until the first bipartition of the nucleus of the oosperm. The synergids supply nutriment to the nucleus of the pollen-tube, and to the oosperm at the moment of its formation. The two polar nuclei, first of all placed at the periphery of the sac, serve for its increase ; subsequently they contribute to the nourishment of the oosphere. The ovule of the Mesembryanthemaceae is also amphitropous- and bitegumented, and displays striking resemblances to that of the Cactaceae. The funicle is again strongly developed, and there is a large formation of starch in the embryo-sac. The principal differences are — the presence of a three-celled cap in the ovary, and the possible fusion of the polar nuclei without the pollen-tube reaching the ovule. In the Crassulacete the ovule is characterised by the hood of the. embryo-sac formed by the epiderm of the nucellus, by the regression of the nucellus, and by the presence of an axial conducting system from the chalaza to the embryo-sac. The ovule is anatropous and bitegu- mented ; the nucellus is greatly reduced ; the embryo-sac is protected* but is isolated in the micropylar region ; it receives the nutrient material only in its enlarged lower portion. The embryo-sac of other succulent plants — Asclepiadese, Euphor- biacem, Portulacacese, Liliaceoe, Amaryllideae — likewise contains starch * but this is also the case with some plants that are not succulent. Significance of Chalazogamy.* — Prof. J. M. Coulter regards ehala- zogamy as a purely physiological phenomenon, not involving any such change of structure as defines a natural group or indicates a line of descent. It ought not, therefore, to be used as an indication of phylo- geny, as suggested by Nawaschin. Parthenogenesis in Thalictrum.f — Mr. D. F. Day reports the fre- quent occurrence of parthenogenesis in the dioecious species Thalictrum Fendleri from Colorado. (2) Nutrition and Growth (including- Germination, and Movements of Fluids). Growth of Pines4 — Prof. R. Hartig has investigated the effect on the growth of pine-stems of various external influences, such as wounds* and the attacks of insects and fungi. Pines attacked by the larva of the moth Psilurn monacha show a smaller yearly growth in all parts of the stem, especially the lowest. Young trees so attacked may regain their strength after a time. A stronger growth on one side of the stem is not. the result of a greater development of foliage on that side ; the strongest growth is always on the side opposite to the prevalent wind. Relation of the Growth of Foliage-Leaves and the Chlorophyll Function.! — Prof. D. T. MacDougal gives the results of a series of experiments on this subject, made on a variety of plants, especially in * Bot. Gazette, xxii. (1896) pp. 227-8. f Tom. cit., p. 241. % Forfct. Nat. Zeitschr., 1896, pp. 1-15, 33-45. See Bot. Ztg., liv. (1896) p. 295. § Joum. Linn. Soc. (Bot.), xxxi. (1896) pp. 526-46 (1 pi. and 1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. r o Oo relation to the deteriorating effect of placing them in an atmosphere devoid of carbon dioxide. The power of developing inactive leaves is not constant in the same species, being dependent on the availability of the reserve-food for this purpose. Material constructed in active chloro- phyll areas, and stored in special organs, may be transported to inactive chlorophyll organs in some plants in light and in darkness, and may be used in such a manner as to allow of the perfect development of those •organs. It is possible for some plants to form perfect leaves in darkness ; some when a portion of the stem only is darkened, and others when the •entire plant is darkened. Placing a leaf under such conditions that it cannot construct food-material, sets on foot the specific regulatory mechanism of the organism in such a manner that the plastic material may be withdrawn and the organ cast off. An exaggerated development of the petiole in darkness may be induced by this mechanism. Recent Literature relating to Leguminosse Tubercles and the Fixation of Free Oxygen. — Prof. Stutzer * reports on some of the most recent papers on the root-tubercles of the Leguminoste. Herren F. Nobbe and L. Hiltuer | continue their experiments on the adaptability of root-tubercle bacteria of unlike origin to different genera of Leguminosae. The experiments showed that an effective inoculation was obtainable with certainty only when inoculations were made from like species. From these experiments two important conclusions are arrived at, namely, that the tubercles have no influence so far as aerial growth is concerned, so long as the plants obtain sufficient nitrogen from the soil, and that, directly the soil-nitrogen begins to fail, those Leguminosse which are devoid of or possess only imperfect tubercles show their want of oxygen ; hence the leaves of the Leguminosse can hardly be considered as organs for assimilating oxygen. M. Gonnermann J obtained pure cultures of tubercle-bacteria in a medium composed of 100 grin, of expressed lupin juice, 10 grm. gelatin, and 3 grm. meat pepton. Salfeld § observed that burnt chalk prevents the formation of tubercles on peas, but B. Tackc,|] who has also investigated the question, finds that Salfeld’s results must be due to some other cause, for chalk seems to favour the formation of root-tubercles. ; Physiology of the Root-Tubercles of Leguminosse. H — From the results of a series of experiments carried on for two years in the S. of F j ance on a number of different sjiccies of Leguminosie, M. C. Naudin doubts the correctness of the prevalent hypothesis that the bacteria of the root-tubercles have the power of absorbing the free nitrogen of the atmosphere, or that they are of advantage to the host-plant. He finds that some species thrive quite as well in sterilised soil, the seeds some- times germinating earlier, and producing stronger plants, than those sown in ordinary soil. The plants grown in sterilised soil had some- times a large number of root- tubercles, sometimes only a few, sometimes * Centralbl. f. Bakteriol. u. Parasitenk, 2tc Abt., ii. (189G) pp. G50-3. f Landwirt. Versuchstat., xlvii. p. 257. % Landw. Jahrb." xxiii. p. 652. § Deutsche Landw. Presse, 1894, No. 83. Ii Mitt. d. Yereins. z. Forderung d. Moorkultur, 1895, p. 3S9. % Comptcs Eendus, cxxiii. (1896) pp. 666-71. 51 SUMMARY OF CURRENT RESEARCHES RELATING TO none at all. No evidence could be obtained of tlieir increasing the richness of the soil in nitrogen. Fixation of Atmospheric Nitrogen by Algse and Bacteria.* * * § — M. R. Bouilhac has experimented on the power of the three algas Schizo- ihrix lardacea , Ulothrix flaccida, and Nostoc punctiforme to absorb free nitrogen from the atmosphere in pure cultures in the presence of the bac- teria of the soil. With the first two species the results were negative ; but the cultivation of the Nostoc in association with the bacteria resulted in a vigorous development of both species and the fixation of atmospheric nitrogen. The power of this alga to absorb nitrogen may be compared to that of the Lcguminosse. Influence of Light and Temperature on Turgor.f — According to experiments made by Mr. E. P. Copeland — on mosses and on seedlings of Vida Faba — the turgor is affected by temperature in a variety of different ways, both direct and indirect. Turgor is regulated by rapidity of growth, rather than the converse. With regard to the connection between etiolation and turgor, the turgor of the root is influenced by the amount of light which the aerial parts receive. Turgor is not affected by the removal of carbon dioxide from the atmosphere ; it is as high in etiolated as in illuminated parts of the plant. Absorption and Emission of Water by Seeds.J — As the result of experiments made on a number of different seeds by M. H. Coupin, it appears that the absorbing power for water of the same species varies greatly, as also does the extent to which the water penetrates the seed. In some saturated seeds there is water which does not belong either to the testa or to the embryo. Dormant seeds absorb, as a rule, as much water as living seeds. The absorbing power of seeds is only slightly influenced by the temperature. Aqueous vapour can be absorbed directly by seeds, especially by the embryo. The bursting of the testa of seeds cannot be attributed entirely either to the increase in size of the embryo or to the direct force of the germinating radicle ; it is probably due to a diastase, which decreases the resistance of the testa by disorganising it. When seeds are plunged in water dilatation takes place, followed by contraction, if the seed has a thin folded testa ; but contraction only if the seed adheres to the embryo. The contraction is due to a chemical combination of the reserve-materials with water; dilatation to rapid imbibition by the testa. When ripening, seeds become desiccated by transpiration, not simply by evaporation. (3) Irritability. Rheotropism.§ — Mr. F. Newcombe has experimented on the existence of rheotropism in Phanerogams. The experiments were made on the roots of suspended seedlings dipping in water. Out of 17 species of Monocotyledons and Dicotyledons, 8 were found to be positively rheo- tropic, i.e. they bent the tips of their roots directly or obliquely against * Comptes Rend us, cxxiii. (1896) pp. 828-30. t ‘ Ueb. d. Einfluss v. Licht u. Temperatur a. d. Turgor,’ Halle, 1896, 59 pp. See Bot. Centralbl., lxviii. (1896) p. 177. t Ann. Sci. Nat. (Bot.), ii. (1896) pp. 129-222 (31 figs.). § Bot. Gazette, xxii. (1896) pp. 212-3. ZOOLOGY AND BOTANY* * * § MICROSCOPY* ETC. 55 the stream. Nine species were indifferent ; none negatively rheotropic. The curvature appeared to be a response to irritation. (4) Chemical Changes (including1 Respiration and Fermentation). Physiology and Biology of Winter-Green Plants.* — Understanding by “ winter-green ” plants not only evergreen perennials, but also such biennial or annual herbaceous plants as maintain the activity of their leaves in the winter, e.g. Senecio vulgaris , Geranium robertianum , Dr. B. Lidforss states that they are characterised by the entire absence of starch from the guard-cells of the stomates during the cold season ; it has already completely disappeared by December ; but its formation is at once induced by a higher temperature. The same is true of the mesophyll-cells of the leaf. These contain, on the other hand, large quantities of a soluble carbohydrate, probably glucose ; and the author regards the transformation of starch into glucose as a protection against cold, similar to the formation of oil in many trees. Submerged plants, mosses, and green algae exhibit similar phenomena. y. General. Divergence of Monocotyledons and Dicotyledons.! — Prof. C. E. Bessey points out that Monocotyledons and Dicotyledons cannot have diverged from one another at what are generally regarded as the lowest members of each group, viz. the Typhaceae, Pandanaceae, Naiadaceae, &e. on the one hand, and the Piperaceae, Chloranthaceae, Salicaceae on the other hand ; since these orders show no kind of affinity with one another. He considers, on the other hand, that external anatomy, histology, and embryology point to a genetic relationship between the apocarpous Monocotyledons (AlismaceaB, Naiadaceae, &c.) on the one hand, and the Thalamifloral Ranales (Ranunculacese, Magnoliaceae, Nymphaeaceae, &c.) on the other hand. Graft-Hybrid.^ — Prof. N. Wille records a remarkable instance of apparent graft-hybridism of a pear on a whitethorn. The fruits are small, pear-shaped, with the colour of the fruit of Crataegus, 5-celled, but usually sterile ; the leaves have all the appearance of pear-leaves. Fossil Plants of the Coal-Measures.§ — Parts 2 and 3 of this important work, by the late Prof. W. C. Williamson and Dr. D. H. Scott, comprise the detailed account of their researches on the roots of Calamites and on Lyginodendron and Heterangium , which appear to belong to a fossil group on the border-land of Ferns and Cycadete. B. CRYPTO GAMIA. Cryptogamia Vascularia. Female Prothallium of the Heterosporous Lycopodiaceae.[| — From observations on the germination of the megaspores of Isoetes malinverniana * Bot. Centralbl., lxviii. (1896) pp. 33-44. f Bot. Gazette, xxii. (1896) pp. 229-32. X Mitt. Biol. Gesell. Christiania. See Biol. Centralbl., xvi. (1896) p. 126. § Phil. Trans. R. S., clxxxvi. (1896) pp. 683-779 (15 pis.). Cf. this Journal, 1895, pp. 338, 660. || Bot. Ztg., liv. (1896) lta Abt., pp. 159-68 (1 pi.). 56 SUMMARY OF CURRENT RESEARCHES RELATING TO and Selciginella ruspidata var. elongata, Herr W. Arnold maintains that the development of the female prothallium presents no essential difference in these two genera. The single nucleus of the spore divides gradually into daughter-nuclei, which are imbedded in the parietal part of the protoplasm, and determine the formation of cells in the prothallium. The mature prothallia closely resemble one another ; they are colourless, and bear only unicellular rhizoids ; the spores germinate while still in the sporange, falling out, in Selaginella, at the time of impregnation; while in Isoetes the young plants are produced within the sporange. The process is compared by the author to the development of the endosperm in Phanerogams. Sporanges on Prothallia.* — Mr. W. H. Lang describes the production of sporanges on prothallia of two ferns, Lastrea dilatata var. cristata gracilis, and Scolopendriwm vulgare var. ramulosissimum. In the case of the former species the midrib of some of the prothallia was elongated into a peculiar cylindrical process containing tracheids. On this pro- cess are produced sexual organs of both kinds ; also sporanges, either on the process or immediately behind it, and either isolated or collected into groups resembling sori ; also single sporanges on the edge of the pro- thallium. Beneath the sporanges a few tracheids were always found. In the hart’s-tonguc the prothallium was prolonged into a similar cylindrical process, which bore a large number of sporanges as well as sexual organs. The author adduces reasons for regarding the production of sporanges on the prothallium as a special case of apogamy. Bivision of the Prothallium of a Fern.f — Mr. E. J. Lowe records some interesting results from the repeated division of the prothallium of Scolopendrium vulgare var. crispum. Some of the fern-plants which sprang from the divided prothallia had a remarkably Marcliantia- like appearance. These fronds appear to have characters intermediate be- tween the sporophoric and the oophoric. Apospory was also observed, as also the formation of antherids and archegones on an entirely new growth of repeatedly divided prothallia. Muscineae. Mucilaginous Paraphyses in a Moss.J — In some of the paraphyses of Diphyscium foliosum , Herr W. Lorch finds bell-shaped membranes attached to the septa. In their youngest stages, an accumulation of mucilage takes place between the cuticle and this membrane, which dis- tends and finally splits the cuticle, producing the bell-shaped structures. Algae. Sarcomenia.§ — Mdmo. A. Weber van Bosse describes minutely the structure of Sarcomenia miniata (Florideae) from South Africa. The cells of the central tube are connected by a very strong strand of proto- plasm. Secondary pores and smaller strands of protoplasm also con- nect the pericentral tubes with one another and with the central tube. * Proc. Roy. Soc., lx. (1896) pp. 250-60. t Journ. Linn. Soc. (Bot.\ xxxii. (1896) pp. 529-39 (2 figs.), f Jahrb. Naturw. Yer. Elberfeld, viii. (1896) p. 86 (1 fig.). See Hedwigia, xxxv. (1896) Rep., p. 121. § Journ. of Bot., xxxiv. (1896) pp. 281-5 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 57 Antlierids occur on the same plant as the cystocarps. The branches are the result of endogenous growth, as in Pytiphlcea and other genera. Fucaceae * * * § — Herr E. Gruber describes in detail the structure of a number of species of Fucaceae, and classifies the genera into six groups, viz. the Durvilleae, Hormosirere, Fuceae, Loriformes, Cystosireae, and Sargasseae. The Durvilleae comprise the genera Durvillsea (including SarcopJiycus and Ecldonia ) and SplacJinidium (?) ; the Hormosirem, Hor- mosira and Notheia ; the Fuceae, Fucus, Pelvetia, Xiphophora, Ascophyllum , Axillaria, Seirococcus, Scytothalia , Phyllosporci, and Marginaria ; the Loriformes consist of Himanthalia alone ; the Cystosireae are divided into Bilaterales and Badiares ; the former including Halidrys, Eifurcaria , Carpoglossum , Myriodesma (?), Platythelia, and Platyldbium ; the latter Cystoseira , Cystophyllum, 1 tormophysa, Coccophora, Scaberia (?), Cysto- pliora , and Langsburgia ; the Sargasseae comprise Anthopliycus , Carpo- phyllum , Contarinia , Pterocaulon , Sargassum, and Turbinaria. Hew Genus of Freshwater Phseosporese.t — Under the name Ueri- baudiella, M. M. Gomont establishes a new genus of Halfsiaceae, with the following diagnosis : — Planta phaeosporina, Crustacea, e strato initiali arete appresso et filis erectis inde ortis formata ; stratum initiate mono- stromaticum, ambitu crescens, cellulis connatis secus series dichotomas flabelliformiter arcuatas ordinatis constitutum ; fila erecta libera, ar- ticulata, monosiphonia, abundanter et plerumque dichotome ramosa, ramis fastigiatis, arete appressis ; sporangia unilocularia in soros baud aggregata, transformatione cellulse superioris filorum ascendentium orta, poro apicali vacuefacta ; sporangia plurilocularia usque adhuc ignota aut nulla. The genus is nearly allied to Symphyocarpus and Litlioderma. H. arverneiisis sp. n. forms a brown coating on mica-schists in running water in Haute Auvergne, Hew Cephaleuros.J— Under the name Ceplialeuros Coffcse, Herr F. A. F. C. Went describes a new species of this genus of Chroolepideae parasitic on leaves of the coffee plant, and follows the various stages of its development. The pigment is blood-red. It causes black spots on the leaves, and the blackening and drying up of the fruit. Pseudocodium, a new Genus of Siphonese.§ — Under the name Pseudocodium De Vriesii g. et sp. n., Mdme. Weber van Bosse describes a new Siphoncan Alga from S. Africa, with the following diagnosis : — Frondes virides, dichotomi ; rami cylindrici, omnino consimiles, ex filis tubulosis subparallelis longitudinaliter dispositi, apice iterum atque iterum divisi, contexti, articuli exteriores apice in vesiculos oblongos evo- luti, corticem pseudoparenchymaticam formantes ; rhizini filiformes cum granulis sabulosis et inter se dense intertextis ; propagatio ignota. Notwithstanding its outward resemblance to Codium, the authoress con- siders the genus more nearly related to Halimeda. Potifer- Galls on Vaucheria.|] — Herr W. Kothert describes in great detail the structure and development of the galls produced on species * Biblioth. Bot. (Luerssen u. Frank), Heft 38, 34 pp. and 7 pis. Cf. this Journal, 1890, p. 69. f Bull. Soc. Bot. France, xliii. (1896) pp. 388-91 (1 pi.)., X Centralbl. f. Bakt., Parasit. u. Infektionskr., 2te Abt., i. pp. 681-7. § Journ. Linn. JSoc. (B .t.), xxxii. (1896) pp. 209-12 (1 pi.). II Jahrb. f. wiss. Bot. (Pfeifer u. Strasburger), xxix. (1896) pp. 525-94 (2 pis.). 58 SUMMARY OF CURRENT RESEARCHES RELATING TO of Vaucheria by Notommata Wernecki. The outgrowths caused by the parasite branch dichotomously or tricliotomously, while the normal Vaucheria- filaments branch only monopodially. The membrane of the gall ditfers from that of the ordinary thallus in thickness and stratifi- cation, and contains substances peculiar to it. The gall is surrounded by a thin layer of mucilage resulting from the disorganisation of the outer layers. The galls probably arise from lateral branches of the thallus formed in consequence of the destruction of the growing point by the parasite. The protoplasm of Vaucheria displays a remarkable resistance to the attacks of the Notommata , which is a true parasite, having nothing but an injurious effect on the host. A new species, Vaucheria Walzi, is described. Fungi. Distribution of Fungi by Snails.* * * § — According to Herr G. Wagner, the carriage of spores by snails plays an important part in the propa- gation of Fungi. This was established in the cases of Plasmopora nivea , the oidium of Erysiphe communis , Puccinia Garyophyllearum , &c. Membranaceous Mycele.| — M. C. van Bambeke describes a mycele which forms extensive white pellicles. The separate hyphae contain irregular flat swellings, which the author regards as spores, and believes that they perform a function as reservoirs of reserve food-material. Chytridium simulans sp. n.J — M. P. A. Dangeard describes this new species of Chytridiaceae, parasitic on an aquatic fungus, probably a species of Pytliium , It is nearly allied to C. suhangulosum, and consists of a zoosporange, with a rudimentary nutrient filament at its base. New Genera of Fungi. § — Abbe J. Bresadola describes the following new genera from Brazil : — Hydnochsete : — Beceptaculum resupinatum, suberoso-coriaceum, hymenium aculeato-dentatum, aculeis subulatis fulvis prseditum ; basidia tetraspora ; sporse hyalinae. In Hydnaceae, near to Asterodon. H. hadia on wood. Molleria : — Stroma subcarnosa, verruciforme, parenchymati foliorum innatum ; perithecia plus minusve immersa; asci polyspori, sporidia subfusoidea, continua, hyalina. In Hypocreacese, near Polystigma . H. sulphurea on living or dead leaves of trees. Herr P. Hennings || finds the following new genus of Gasteromycetes among fungi from New Zealand : — Clavogaster : — Perithecium subcoria- ceum, persistens, e stratis binis discoloribus efformatum, clavatum, stipi- tatum ; capillitium subfasciatum, in cellulas favosas polyedras ; sporis levibus, ellipsoideis, coloratis, pedicellatis. Near to Hippoperdon. Behaviour of the Nucleus in the Development of the Fructifica- tion of the AscomycetesA — Mr. B. A. Harper has followed out the process of nuclear division in the formation of the ascus, especially in Sphserotheca Castagnei , Erysiphe communis , and Ascobolus sp. The ascogones of these three genera resemble one another in essential points. * Zeitsclir. f. Pflanzenkr., 1896, p. 144. See Hedwigia, xxxv. (1896) Rep., p. 110. t Bot. Jaarb. Dodonaea, viii. (1896) p. 121 (1 pi.). See Hedwigia, xxxv. (1896) Rep., p. 118. X Le Botaniste (Daugeard), v. (1896) pp. 21-6 (1 fig.). § Hedwigia, xxxv. (1896) pp. 287 and 298. || Tom. cit.. pp. 303-4 (4 figs.). 1 Jahrb. f. wiss. Bot. (Pfeifer u. Strasburger), xxix. (1896) pp. 655-84 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 59 The ascogenous cell of Ascobolus corresponds to the cell from which most, and probably all, the ascogenous hyphse of Erysiphe spring, and to the ascogenous cell of Sphserotlieca. In the two latter genera a portion of the nucleus resulting from the division of the fertilised oosphere has a purely vegetative function, and finally disappears, the other portions forming the ascospore ; while in Ascobolus , the entire contents of the ascogone are used up in the production of the ascospores. The asco- genous hyphse of Erysiphe and Ascobolus are undoubtedly of the same morphological value; and the formation of asci from these hyphse presents essentially the same process in both. In the case of the Erysiphete at least we may assume that the ascus-fructification is a non-sexual spore- fruit, originating from an impregnated oosphere. Reproduction of Spheerotheca iCastagnei.* * * § — M. P. A. Dangeard confirms the statement of Harper, that a fusion takes place between the two nuclei of the ascus in this fungus ; but disputes his assertion that the ascus is itself the result of the conjugation of a nucleus derived from an antherid, and the nucleus of the oogone. Tuberacese.f — Parts 57, 58 of Rabenhorst’s Cryptogamic Flora of Germany are mainly occupied by a monograph, by Dr. E. Fischer, of the German Tuberaceoe. The order is divided into three families, viz. : — (1) Eutuberineae ; receptacle with passages either hollow or filled with a weft of liyphae (less often a single cavity), opening outwards, the walls covered by the ascogenous layer ; (2) Balsamiese ; receptacle with hollow closed chambers, not opening outwards, the walls covered by the asco- genous layer ; (3) Elaphomycetineae ; asci imbedded in clusters or bands, or regularly distributed through the receptacle. The Eutuberineae com- prise the genera Genea (6 spp.), Hydnotrya (3), Stephensia (1), Pachyphloeus (3), and Tuber (16). The Balsamieae are composed of the single genus Balsamia, with 3 spp. The Elaphomycetineae include Thjdnobolii.es (3 spp.), Choiromyces (1), Terfezia (1), Picoa (3), Elaphomyces (21), and Onygena (5 spp.). The small group of Hemiasceae — Ascoidea (1 sp.), Protomyces (4), Monascus (3) and Endogone (4 spp.) — follows. The illustrations are numerous and excellent. Fructification of Antennaria4 — In addition to the forms of fructi- fication of Antennaria scoriadea already known, Dr. Neger describes a new one, found on several trees in Chile, on which the fungus is parasi- tic. It resembles a conidial form of Cladosporium Fumago , known as coniothece, and consists of small black cushions, resembling peritheces, from the margin of which multicellular bodies become detached, and these develope, in certain conditions, into a mycele. Parasitic Fungi. — M. E. Prillieux§ traces a destructive disease of the chicory to Phoma albicans , the pycnid generation, of which Pleospora albicans is the perithecial form. Herr G. Wagner II confirms the observation of Magnus of the identity * Le Botaniste (Dangeard), v. (1896) pp. 27-31. Cf. this Journal, 1896, p. 339. t ‘ Kryptogamen-Flora v. Deutschland u.s.w.’ (Rabenhorst), ler Bd., 5te Abt., Lief. 57, 58, Leipzig, 1896, 131 pp. and many figs. X Centralbl. f. Bakteriol. u. Parasitenk., 2te Abt., ii. pp. 613-5. § Bull. Soc. Mycol. France, 1896, p. 82 (1 fig.). See Bot. Centralbl., lxvii. (1896) p. 215. || Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 212-5. 60 SUMMARY OF CURRENT RESEARCHES RELATING TO of Puccinia sylvatica and P. sessilis. A number of other “ species sorores ” •are also included in the same cycle of development. Herr P. Magnus * * * § describes a new species of Cintradia, C. Seymour - iana, parasitic on Panicum crus-galli in N. America. Prof. M. Shirai f describes four new species of Exobasidium from Japan, viz.: — E. Camellise, parasitic on Thea japonica , E. japonicum on Phododendron indicum, E. hemisphsericum on P. Metternichii , and E. pen- tasporium on P. indicum. A common disease of the Lombardy poplar is attributed by M. P. A. Hangeard J to a different cause from that assigned to it by MM. Vuille- min and Prillieux. He finds on the living branches a species of Cali- cium , C. populneum, belonging to a genus usually placed among the Lichens, but here wanting its algal constituent, and therefore carrying on a parasitic existence on the living tissues. On the young roots he found also an undescribed species of Chytridiaccte, which he names Phizophagus populinus. Herr K. Starback § describes the development of Sphserulina halophila, belonging to the Pyrenomycetes, parasitic on the leaves of Heliantlius peploides. Saceharomyces guttulatus Hob.|] — Dr. L. Buscalioni describes the structure and life-history of this species, found in the intestinal canal of rabbits and other herbivora. He finds it to be a true Saccharomycete, capable of multiplication by spores and by gemmation. It is furnished with a nucleus which divides during the processes both of gemmation and sporulation. The mode of nuclear division is very different from that observed in other fungi, and appears to resemble more or less that which takes place in certain Algos ( Valonia, Godiuni). The process is probably one of karyokinesis, greatly reduced during sporulation, and of fragmen- tation during gemmation. The mode of life of Saceharomyces guttulatus is parasitic, or at least endophytic. Fertilisation of the Uredinese.l — M. Sappin-Trouffy repeats his ob- servations on this process, and points out that the reduction in the num- ber of the chromosomes and in the chromatic substance is a phenomenon of impregnation both in flowering plants and in the Uredinese ; but that in the latter it takes place after, instead of before, fecundation. The result is the same. The “ egg ” (oosperm) in both cases preserves the proper- ties of the species, and transmits them in their integrity to the descend- ants with the same number of chromatic elements. Development of iEcidia.** — Mr. H. M. Kichards has studied the de- velopment of the aecidia of the Uredineae, especially that of Uromyces Galadii. He states that the hymenium is formed by budding from seve- ral fertile primary filaments. The basids are produced especially on the * Tom. cit., pp. 216-21 (1 pi.). t Bot. Mag. (Tokyo), x. (1896) pt. ii. pp. 51-4 (1 pi.). X Le Botaniste (Dangeard), v. (1896) pp. 38-43. Cf. this Journal, 1889, p. 681. § Bih. K. Svensk. Yet. Ak. Hand!., Afd. iii. 1896 (1 pi.), See Hedwigia, xxxv. 0896) Rep., p. 115. \\ Malpigliia, x. (1896) pp. 281-327 (1 pi.). If Le Botaniste (Dangeard), v. (1896) pp. 32-7 (1 tig.). Cf. this Journal, 1S96, p. 342. ** Proe. Amer. Acad. Arts and Sci., xxxi. (1896) pp. 255-70 (1 pi.). See Bot. Centralbl., lxviii. (1896) p. 87. ZOOLOGY AND BOTANY* * * § MICROSCOPY, ETC. 61 periphery of the hymenium ; but in certain cases young basids also ap- pear in the more central region between the older ones. The formation of the peridium commences by the differentiation of the apical cells of the older chains of spores, advancing from the centre towards the peri- phery. The author found two nuclei, not only in the spores, but also in all the other parts of the eecidia, in the hyphse, the peridia, and the pseudo-parenchyme of the early stage ; in the spores three nuclei were sometimes observed. Parasites of the Uredineae.* — M. Sappin-Trouffy describes two spe- cies of fungus-parasites found on the Uredinese : — Tubercularia persicinat on the aecidia of a number of different species ; and Darluca Jilum , on uredospores and teleutospores of species of Puccinia. Puccinia graminis.f — Pursuing his investigations on the various forms of this parasite, Herr J. Eriksson finds that their mcidium-stages on Berber is and 3Iahonia are distinct, as well as their teleuto- and uredo- stages. Although the Berberis may bear a number of different mcidium- forms, each one can, as a rule, give rise only to its special teleuto- or uredofform, and can therefore infect only those species of grass on which it grows. The forms previously described as ff. Airse, Pose, and Agros - tidis appear to be quite innocuous to corn-crops. Auricularia auriculae- Judse 4 — M. Sappin-Trouffy describes the struc- ture and development of this fungus (popularly known as Jew’s-ear or Judas’s-ear), which he regards as forming a link between the Uredineas and the Protobasidiomycetes. The basids are septated transversely, the probasid being homologous to the teleutospore of a Goleosporium ; the promycele is formed within it. Ringworm Fungi.§ — Drs. T. C. Fox and F. R. Blaxall have made a conjoint inquiry into the plurality of fungi causing ringworm in human beings, as met with in London. The authors’ work was carried out on lines similar to those of Sabouraud, of whose observations the present researches are both a confirmation and a criticism. Sabouraud divided ringworms into microsporous and macrosporous. The latter were fur- ther subdivided into Trichophyton megalosporon endothrix and Tr. meg . ectothrix , or rather endo-ectothrix. The ectothrix ringworms were stated to be of animal origin. In London, from 80-90 per cent, of ringworms were found to be due to microsporcn ; those due to endothrix were about 4 per cent. (14 in all) and the remainder to ectothrix. The chief points in which the authors differ from Sabouraud are that eircinate lesions of the glabrous skin accompany the invasion of the hairy scalp by micro- spora much more frequently than Sabouraud allows. They do not agree with Sabouraud as to the arrangement of the mycele in hairs invaded by microspera. They find his descriptions to be incomplete in many respects, and that he is too dogmatic on many points. In the Ectothrix Tricho- plytci they find that the hairs themselves are very often implicated. * Le Botaniste (Dangenrd), y. (1896) pp. 44-52 (2 figs.). t Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxix. (1896)’pp. 499-524. Cf. this. Journal, 1895, p. 209. % Le Botaniste (Dangeard), v. (1896) pp. 53-8 (4 figs.). § Brit. Journ. Dermatol., viii. (1896) pp. 241-55, 291-308, 337-59, 377-84 (11 pis.). 62 SUMMARY OF CURRENT RESEARCHES RELATING TO Similar results to those described by Sabouraud were onfy attainable by using exactly the same media ; hence it would seem that ringworm fungi are very sensitive to their environment. The authors found that the duration of life on potato was longer than three weeks, and might be maintained for at least a year. They differ as to the mycology of ring- worm, finding in Microspora spore-bearing hyphse and spores exactly similar to those seen in the Endotlirix and Ectothrix Trichophyla. The characteristic pectinations were observed, but only on the submerged liyphas. In all the groups the aerial hyphae show the same fructifica- tion. In Microspora chlamydospores were always present, generally in Ectothrix , and never in Endotlirix Trichophyta. Myxomycetes. Sappinia, a new Genus of Acrasiese.* — Under the name Sappinia pedata g. et sp. n., M. P. A. Dangeard describes a new type of this family of Myxomycetes, found on old cultures of horsedung. The separate Myxamoeba3 may become encysted, or they become fixed at the end of stalks ; resting cysts are also formed. Some of the Myxamcebae enclose spherical endogenous germs, composed of a large number of small rounded corpuscles ; they are apparently produced by a parasitic Micrococcus. Cribraria and Physarum. f — On the ground of the structure of the sporange, Dr. C. Schilbersky proposes to detach Cribraria mirabilis from that genus, and to place it under Dictydium. He also describes a new species, Physarum mucoroides, parasitic on the stem and leaves of Sedum carneum. Protopliyta. “• Schizopliycese. Growth of Diatoms.f — Further experiments by Mr. G. C. Whipple show that abundant food-supply is not the only condition for the rapid increase of diatoms ; temperature, amount of light, and other factors also influencing their growth. In common with all other chlorophyllaceous plants, they will not grow in the dark ; while, on the other hand, bright sunlight kills them. The intensity of the light below the surface being affected by the colour of the water, diatoms are found most abundantly in light-coloured waters. Different genera, however, differ in this re- spect ; Melosira does not require so much light as Synedra . Weather has a marked influence on their growth. They increase most rapidly during those seasons of the year when water is in circulation throughout the vertical ; during these periods not only is food more abundant, but the vertical currents keep the diatoms near the surface, where there is light enough to stimulate their growth, and where there is abundance of air. Some species display very strong positive heliotropism. Formation of Auxospores in the Diatomacese.§ — Herr H. Klebahn gives a resume of all the cases hitherto described of the formation of auxospores in diatoms, which he classifies under five heads, viz. : — (1) Re * Le Botaniste, v. (1896) pp. 1-20 (4 figs.). t Bot. Centralbl., lxvi. (1896) pp. 81-6 (1 pi.). t Technology Quarterly (Boston), ix. (1896) pp. 145-68. Cf. this Journal, 1895, p. 315. § Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxixT (1896) pp. 595-654 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 63 juvenescence of a single cell, accompanied by an increase in size; the simplest and a common type. (2) Two daughter-cells are produced from the protoplasm of a mother-cell, and from these arise two auxospores (. Achnanthes longipes , Rhabdonema arcuatum). (3) Two cells, lying side by side, cast off their old valves, and each grows into an auxospore, without any previous fusion or any visible interchange of contents ; much the most common type. (4) A true conjugation takes place ; the protoplasts of the two cells fuse together into one, and this grows into an auxospore ; also common. (5) Before conjugation the protoplasm of each of the two cells divides beforehand into two daughter-cells, and two auxospores are formed by the fusion of a daughter-cell from each mother-cell with the daughter-cell of the other one lying opposite to it ( Amphora ovalis, Epithemia Argus, RJiopalodia gibbet, &c.). The process is then described in detail of the formation of two auxospores in Rhopalodia ( Epithemia ) gibba, which was found abun- dantly imbedded in the gelatinous envelope of Schizochlamys gelatinosa at PI on. The fixing of the cells during conjugation is assisted by peculiar gelatinous caps at their apices. Since the two nuclei which unite to form the nucleus of the auxospore are derived from two cells which have no near relationship to one another, the author regards the conjugation which results in its production as a true sexual process. Sporulation of Diatoms.* — Comte Abbe F. Castracane proposes to collect together all the recorded instances of the multiplication of diatoms by means of internal spores, and to found, on the variations in this mode of propagation, a new and more natural system of classification. He would classify e.g. the species of the present genus Synedra under two distinct genera, one terrestrial, the other marine, differing from one another in exhibiting an entirely different mode of sporulation. New Genera of Cyanophycese.f — Floating on the surface of a dark well, M. E. Roze found a gelatinous mucus, with very pale yellow spots, caused by an organism for which he constitutes a new genus of Chroo- coccacese Aplococcus, nearly allied to Aphanocapsa , and forming the lowest member of the family, with the following diagnosis: — Cellulae sphaericse, liberie, absque integumentis, in thallis mucosis homogeneis amorphis v. formge definitae nidulantes; cellularum divisio in unam solam directionem. The cells of A. natans sp. n. have a diameter of about 0*5 fx. They are largely attacked by a Micrococcus, probably undescribed, which appears to live on the gelatinous thallus of the Nostocaceee. From an adjacent well was obtained a filamentous organism, which becomes the type of another new genus of Cyanophyceae, Clonothrix , alied to Cladotlirix. C. fusca sp. n. is characterised by remarkable flask- shaped swellings of the branches. The diagnosis of the genus is as follows : — Trichomata elongata, articulata, simplicia v. pseudoramosa, plus minusve distincte vaginata; propagatio cellulis articulorum dis- junctis v. e medio fractarum vaginarum emergentibus ; generatio dubia, ampullis exiguis, apice evanescentibus, in quibus plasma fere hyalinum primo vacuolas deinde granulos paucos continet. * Atti Accad. Pont. Nuovi Lincei, xlix. (1896) pp. 107-13. f Journ. de Bot, (Morot), x. (1896) pp. 319—23, 325-30 (14 figs.). 64 SUMMARY OF CURRENT RESEARCHES RELATING TO Nostocaceae.* — Herr P. Kichter prefers the division of the Nosto- caceae into Psilonemeae and Trichophoreas, adopted by Thuret and Bornet, rather than that proposed by Hansgirg, Bornet, and Flahault, into Heterocysteae and Homocysteae ; the presence or absence of heterocysts not being of a sufficiently constant character to use for a primary classi- fication. He gives reasons for identifying Aphanizomenon incurvum specifically with A. flos-aquse, and for regarding Oscillatoria Agardhii as a sterile form of the same species. A new species, Aphanizomenon hol- saticum , is described. Hassallia and Tolypothrix.f — M. M. Gomont proposes the following new diagnosis for distinguishing these two genera : — Hassallia. Fila fragilia ; articnli diametro trichomatis semper breviores. Tolypothrix. Fila flexilia ; articuli diametro longiores, vel sub-quadrati. £. Schizomycetes. Action of Glycerin on the Growth of Bacteria.J— Drs. S. M. Copeman and F. K. Blaxall give a preliminary account as to experiments on the action of glycerin on the growth of bacteria. The experiments had special reference to the bacteriology of small-pox and vaccinia, and to the purification and preservation of vaccine lymph. The method pursued was to add known quantities of glycerin to tubes of beef-pepton- brotli, and subsequently to inoculate these with equal quantities of pure cultivation, and incubate at blood-heat and at room-temperature. Control inoculations in ordinary beef-broth were invariably made. Inocula- tions were afterwards made from the broth-tubes to solid media at vary- ing intervals of time, in order to see whether the particular microbe was still capable of growth or not. The micro-organisms used were St. py . aureus , St. py. albus, Sir. pyogenes, B. pyocyaneus, B. subtilis, B. coli com- munis, B. diphtherise, and B. tuberculosis. Small-pox and vaccine material in the form of “crusts” and lymph were also used. The results were that no visible development took place when more than 30 per cent, of glycerin was used. All micro-organisms were killed in it in less than a month with 30-40 per cent, of glycerin, except B. coli com. and B. subtilis, when kept in the cold. B. coli com., unlike B. typhosus, resists the action of 50 per cent, glycerin in the cold for a considerable period, a fact which might be used for differentiating these microbes. Small-pox and vaccine material are completely sterilised, so far as extraneous microbes are concerned, in a week by the presence of 40 per cent, of glycerin in the broth- tubes. Associated Action of Bacteria.§ — Herren Fesina and Honl think that secondary infection and mixed infection should be sharply demar- cated. By secondary infection they understand a process wherein a. second pathogenic organism, usually a coccus and most frequently strepto- coccus, is associated with the first, and, without aiding in the develop- ment of the primary process, excites quite independently a second new septic condition. Of mixed or multiple generalised infection, some cases * Hedwigia, xxxv. (1896) pp. 263-75. f Bull. Soc. Bot. France, xliii. (1896) p. 382. $ Proc. Brit. Assoc , 1896. § Intern. Klin. Rundschau, 1891, Nos. 49 and 50. See Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 689-90. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 65 are mentioned where two quite different microbes combine to produce a definite pathological process ; the combined action is far more serious than that of either alone. Thus, in a case of meningitis from otitis- media, Friedlander’s bacillus and B. pyocyaneus were isolated. Alone, it is quite rare for either of these to excite meningitis. Two or several microbes do not invade the body simultaneously ; a definite pathological condition has already declared itself at the time of the invasion of the second. The latter immediately excites its own peculiar action, and does this, not by superadding a different pathological condition, but by in- tensifying the action of the first. As an example is quoted the case of simultaneous bacillar meningitis and croupous pneumonia. All at once the symptoms indicated a vertical meningitis as well. The autopsy re- vealed the presence of tubercle bacilli at the base of the brain, and pneumonia cocci over the vertex. Influence of the Induced Current on Bacteria.* — Dr. H. Friedenthal reports on some experiments he has made by exposing suspensions of M. prodigiosus (5) and of beer yeast (2) to the action of the induced current. The electric current had little or no effect. The exposure was for about one hour and a half, and the strength varied from 14 to "20 amperes. The current was passed along a spiral round the tubes filled with the fluid containing the bacteria, a low temperature being maintained by a stream of cold water. Relation of Immunising Substances to Specific Microbes.f — Dr. E. Klein finds that when suspensions of virulent diphtheria bacilli in bouillon are injected into the peritoneal sac of guinea-pigs, most of the animals remain healthy, the minority dying on the third or fourth day. The survivors are eventually able to tolerate a large dose, and their blood serum is so strong that 0*25 ccm. is able to neutralise a fatal dose administered subcutaneously. It was further found that the sub- cutaneous injection of antitoxin had the same effect, and that no morbid action occurred from the subcutaneous injection of a fatal dose of a gelatin culture previously mixed with 0*1 ccm. of antitoxin. This resistance would therefore seem to be due to germicidal substances arising directly or indirectly out of the bacteria themselves. Gases produced by certain Bacteria.^ — Mr. L. H. Pammel and Miss E. Pammel, after discussing the work of previous observers, narrate the method of their own procedure, aud give the results of their experi- ments with certain gas-forming bacteria. Bacillus aromaticus , obtained from rotting cabbage, coagulated milk in 48 hours, and produced on potato a yellowish-white growth. Grown in pepton-bouillon-glucose and saccharose, there was copious develop- ment of gas ; with lactose none. Bacillus gasoformans , obtained from water, coagulated milk with alkaline reaction, the growth on potato being copious, granular, and wrinkled. This bacillus, like the preceding, developed gas copiously on pepton-bouillon containing glucose and saccharose, but none with lactose. Bacillus mesentericus vulgatus coagulates milk with acid reaction, * Centralbl. f. Bakteriol. u. Parasitenk., lta Abt., xx. (1896) pp. 505-8. 4 Tom. cit., pp. 417-20. % Op. cit., 2te Abt., ii. (1896) pp. 633-50 (1 pi.). 1897 F 66 SUMMARY OF CURRENT RESEARCHES RELATING TO and forms on potato a shining white growth. There is no gas formed with glucose, but copious development with lactose and saccharose. Bacillus coli communis developed gas in all three media. Negative results were obtained from a micrococcus. All the four bacilli were mobile, and all produced an acid reaction of the medium. The gases produced were carbon dioxide and hydrogen. Abilities of certain pathogenic Microbes to maintain their exist- ence in Water.* — From the observations of Dr. E. Klein it seems that cholera bacteria can live in Thames water for at least 42 days, and that they are demonstrable therein for a longer period than the typhoid fever bacilli, which could not be found after 36 days. The foregoing results were obtained with natural Thames water ; but when the water was filtered and sterilised these bacteria survived for a longer period. Bacteriological Examination of Water for Coli Bacteria.f — Dr. E. von Freudenreich has made experiments for the purpose of ascertaining whether coli bacteria multiply with great rapidity in water. The specimens were cultivated in milk-sugar-bouillon, and then inoculated in sterilised and unsterilised water. The sources of both kinds of water were various. In series A (sterilised water) there was increase six out of seven times. In series B (unsterilised water) there was increase in ten, and decrease or absence in four cases. No definite conclusion appears to be possible from the as yet too few experiments, though they are sufficient to suggest that when water is to be examined for coli bacteria (by Parietti’s, the milk-sugar-bouillon, or any other method), the exami- nation should be made at once. Pathogenic Bacteria in Buried Bodies.}: — Prof. W. Losener has made some experiments with pathogenic bacteria relative to the time these organisms retain their vitality in buried corpses, and the dangers supposed to be incurred by contamination of the soil and the soil-water by these microbes. The method adopted was to insert the virus into pigs, which were wrapped up in linen cloths, placed in wooden coffins, and buried in a soil partly sandy, partly clayey. The bodies were infected by injecting into the axillary artery dilute cultures, or by inserting into the thoracic or abdominal cavity cotton- wool saturated with cultures, and even by inserting infectious viscera, such as tuberculous lungs or typhoid spleen. The bodies were buried at a depth of 1 J-2 metres ; they were only dug up once, and measures were taken for obtaining samples of the soil-water and the soil in their immediate vicinity after varying intervals of time. The microbes used were those of enteric fever, cholera, tuberculosis, tetanus, suppuration, and anthrax. It would seem that the typhoid germ may retain its vitality under the conditions mentioned for at least 96 days. The cholera vibrio was demonstrable up to the 28th day, but only in the fluid taken from the abdominal cavity wherein a cotton-wool plug had been inserted. The observations on tuberculosis were carried on for two years. In only two * Ann. Rep. Loc. Gov. Board, 1894-5. See Centralbl. f. Bakteriol. u. Para- sitenk., lte Abt., xx. (1896) pp. 688-9. f Centralbl. f. Bakteriol. u. Parasitenk., lt0 Abt., xx. (1896) pp. 522-7 ; also Ann. de Microgr., viii. (1896) pp. 415-23. X Arb. a. d. Kaiserl. Gesundheitsamte, xii. See Centralbl. f. Bakteriol. u. Para- sitenk., lte Abt., xx. (1896) pp. 454-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 67 cases (dug up at 60 and 95 days) were tubercle bacilli found, and then only in remains of introduced viscera. Tetanus microbes were not found after the 234th day. Staphylococci and Streptococci were regularly found during the first six months. M. teiragenus, pyocyaneus, and B. Friedlaender soon succumbed. The experiments with anthrax were intended to ascertain if there was any dissemination of the germs owing to the rise and fall of the soil-water, for the resistance of anthrax spores to putrefaction was settled long ago. One experiment gave positive results, and that was probably more or less accidental. The main result of the author’s work seems to be that, provided the soil around a corpse have good filtering properties, though the layer be not thick, there is practically no chance of dissemination of a virus, whether there be permanent or variable saturation of the soil. Epidemic among Pigeons caused by Bacillus coli communis.- — Prof. F. Sanfelice records an epidemic among pigeons caused by Bacillus coli communis. There were peritonitis, enlargement of the spleen, and suppurative inflammation of the mucosa of the oviducts. B. coli com- munis was found in the spleen, liver, and heart-blood. Pigmentary Functions of Bacillus pyocyaneus.f — Dr. M. Nicolle and Dr. Zia Bey record observations, made from four different samples of Bacillus pyocyaneus , relative to the pigmentary functions of this organism. The general characters of the four samples were as follows : — Mobile; not staining by Gram’s method; liquefying; presenting the classical aspect on potato; exhaling the characteristic odour; in vacuo growing with difficulty and without pigment. All were pathogenic to rabbits. All four samples produced more pyocyanin than the typical bacillus, and on one medium, the composition of which is not given, the pigment was greenish and non-fiuorescent, on the other four media green and fluorescent. The authors also found that the presence of phosphates in the media, while extremely favourable to the formation of fluorescent pigment, is not an indispensable condition thereof. While the pyocyanin, the greenish pigment, and the rusty-brown pigment (resulting from the oxidation of the fluorescent green) pass readily through the Chamberland filter, the fluorescent green pigment is entirely held back. Agglutinative Action of Typhoid-Serum. — The agglutinative action of the blood-serum of persons suffering from enteric fever on cultures of the typhoid bacillus, has been largely made use of for the diagnosis of this disease since it was introduced by Widal. J The method of Widal is simple, rapid, and effective. It merely consists in adding a drop of serum or of blood to ten drops of a young bouillon culture of Bacillus typhosus. If there be “clumping” and immobilisation of the micro- organism the diagnosis of enteric fever is confirmed. Prof. S. Delepine and Dr. E. J. Sidebotham § record the results of their investigation by this method on twenty-five cases of undoubted * Zeitschr. f. Hygiene u. Infektionskr., xx. p. 23. See Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) p. 753. f Ann. Inst. Pasteur, x. (1896) pp. 669-71. % Lancet, 1896, ii. p. 1371. § Tom. cit., pp. 1587 and 1665. F 2 68 SUMMARY OF CURRENT RESEARCHES RELATING TO typhoid fever, on ten cases of other febrile diseases, and on normal blood. Positive results were obtained with the typhoid fever cases only. The reaction is usually obtained from the fourth day to long after the fifth week. After the ninth day the reaction is usually in- stantaneous. Though the action can be obtained with dry serum, its immobilising and agglutinative properties are sooner lost than those of fluid serum. According to Dr. H. E. Durham, * the reaction is not always obtainable, for in a series of ten cases no reaction occurred in four, and he concludes that an absolute diagnosis cannot always be made by this method. The best procedure for obtaining serum is to prick the lobule of the ear and allow 0 • 2-0 * 3 ccm. of blood to trickle into a test-tube held horizontally. After the blood has clotted, the serum can be removed, or the blood may be slowly centrifuged. Dr. A. S. Griinbaum,'j' who made experiments on the agglutinative action, states that it is only in cases of enteric fever that the serum shows a distinct agglutinative action within 30 minutes, when diluted sixteen (or more) times. The method recommended is to take blood from the ear, and centrifugalise it in a U-shaped capillary tube. The serum is afterwards blown on to a slide and then mixed with bouillon. An emulsion of typhoid bacilli in bouillon is then made, and the mixture examined to make certain there are no clumps therein. A small drop of the diluted serum and a similar drop of the emulsion are mixed on a cover- glass and examined as a “ hanging drop.” If the bacilli aggregate in 'dumps with impaired or lost mobility within 30 minutes, the reaction indicates enteric fever. The reason for diluting the serum is that if undiluted the serum of enteric fever patients may exhibit a stronger re- action with the cholera vibrio or Bac. coli com. than with B. typhosus. The time limit is necessary, because almost every human serum, even when diluted, will eventually produce an agglutinative action. Diphtheria or Diphtheroid Bacilli in Empyema Pus.f — Dr. J. Trumpp records a case of empyema from which was isolated, among other microbes, a bacillus having the morphological characters of Ba- cillus diphtherise Loeffler. Even grape-sugar bouillon became acid in 24 hours, and showed a flocculent deposit. Experiments on animals showed, however, that the cultures were devoid of virulence. This absence of virulence raised the question whether the bacillus was that of true diphtheria, pseudodiphtheria, or a diphtheroid organism. The question was answered by injecting a guinea-pig with 0*35 ccm. of diphtheria toxin as well as the cultivation. In this way virulence was regained, and by the third remove the animal died in 12 hours. This method of restoring the virulence is apparently new, and is certainly simple. * Tom. cit., p. 1746. f Tom. cit., pp. 806 and 1747. X Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 721-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 69 MICROSCOPY. Text-Books of Histology.* — Both the books mentioned below are excellent examples of the progress of modern histology, and of the fact that enthusiasm for details and the minutiae of methods has not thrown out of perspective a comprehensive and even philosophical treatment of a great subject. As a science, histology is dependent wholly on mani- pulative details ; but it is a notable fact that, in these two latest books which deal with it, its relations to biology as a whole are steadily, and with philosophical acumen, kept in view. The entire ground is covered by each of these books, and both jDresent much more of the earnestness of the teacher and the enthusiast than is to be found in the majority of even good text-books. In Mr. Clarkson’s treatise the practical side of histology is well and carefully presented. His treatment of “ General Methods,” in- volving the examination of tissues, and including dissociating, softening, hardening, imbedding, freezing, cutting, staining, and mounting, is concise but sufficient, while his treatment of £i Simple Tissues ” we may commend with supreme confidence to the student. It however includes t; The Animal Cell,” and as this involves its nature, its nucleus, and the whole subject of karyokinesis, we might have desired a more expansive treatment ; but we are bound to remember that, relatively large as the book is, nothing was easier than to lose perspective in dealing with the descriptive and practical aspects of such a wide sub- ject, which, as the author himself tells us, “ cannot aspire to be of the nature of an exhaustive treatise on any part of it.” But even this part has the advantage of great clearness, and shares with the entire book the quality of not being merely descriptive, but, at least to the limits required by the student, thoroughly practical. Moreover, the illustra- tions, from their accuracy and excellence, must prove of great value to those for whom the book was written. Considering the professed object of the work, the whole subject of Histology is dealt with in successive chapters, which we venture to think represent honest and sincere work. Everywhere the least has been said consistently with intelligibility, so that on the whole subject the most might be said ; and we believe that the student who will as conscientiously work through the pages of this book as its author has conscientiously prepared it, will at least have a general mastery of his subject, and if such be his object, he will have laid a good foundation for future original research. Prof. Duval’s “ Precis d’Histologie ” has a larger and higher aim than Mr. Clarkson’s manual ; it is, indeed, one of the most compre- hensive and philosophical treatises of the general subject with which we are acquainted. It contains more than twice as much matter as the * ‘A Text-Book of Histology, Descriptive and Practical. For the Use of Students. By Arthur Clarkson, M.B., C.M. Edin., with 174 original coloured illus- trations. Bristol, Wright & Co. ; London, Simpkin & Co., 1896,’ xx. and 554 pp. ‘Precis d’Histologie. Par Mathias Duval, Professeur a la Faculte de Medecine de Paris, Membre de l’Academie de Medecine. Ouvrage accompagne' de 408 figures. Paris, Masson et Cie., Editeurs-Libraires de l’Academie de Medecine, 120 Boulevard Saint-Germain, 1897,’ xxxi. and 956 pp. 70 SUMMARY OF CURRENT RESEARCHES RELATING TO English work, and is yet not complete. It is the purpose of Prof. Duval to publish a further portion so that the combined work shall he what would appear to us to be much more than a Handbook on Histology and eared in this J ournal (1896, p. 681), the generality of Abbe’s method of studying the images formed by Microscopes is not sufficiently appreciated. In the present memoir, therefore, his object is to offer a fuller account of this generality than he has given elsewhere.f The author begins by contrasting two of the many possible methods of resolving the disturbance of the tether in front of and close to the object. The most obvious resolution into spherical waves is the foun- dation of Airy’s method of studying the images formed by telescopes, while the mode of resolution into plane waves is the foundation of Abbe’s method of studying the images formed by Microscopes (the Diffraction Theory). As fundamental principles, seven propositions are then discussed, with the help of which, and the more familiar laws of optics, it is claimed that nearly everything in microscopic vision may be explained. Proposition 1. However complex the contents of the objective field , and whether it or parts of it be self luminous or illuminated in any way , however special , the light which emanates from it may be resolved into undulations , each of ivhich consists of uniform plane waves. This is practically an extension of Fourier’s theorem. By the objective field is to be understood the whole of the object and its sur- roundings, of which an image is formed by an instrument, or in the eye of the observer. To prove this proposition the author conceives a plane through the object, perpendicular to the line of sight (the Objective Plane), to be divided up into squares, one containing the projection of the objective field, and the others replicas. The proof then follows from the fact that a point in the objective field with the corresponding points in the replicas forms a system which by the theory of diffraction gratings will produce a disturbance of the aether resolvable into plane waves. Proposition 2. The standard image may be regarded as resulting from the superposition and mutual interference of uniform luminous rulings of equidistant parallel bright lines , extending over the whole field of view ; each ruling being pro- duced by the convergence upon it, after the reversal, of two or more of the undulations of uniform plane waves, into which the light emitted by the object may be resolved. By the standard image is meant the image formed by imagining the undulations to travel backwards to the positions that had been occupied by the original object. The image thus formed will therefore be the most perfect which the light from the object is capable of forming, and may be used as a standard of perfection which cannot be exceeded by the images formed by any optical contrivance. In the microscopic image, owing to the fact that the angular aperture of the objective is less than 180°, the amount of detail falls short of that in the standard image. With the best immersion lenses with aperture 120° * Phil. Mag., xlii. (1896) pp. 332-49, 423-42, 499-528. f See ‘On the Foundation of the Diffraction Theory,’ English Mech., December 13, 1895, p. 380. 72 SUMMARY OF CURRENT RESEARCHES RELATING TO or 130°, little more than half the light would be caught by the objective, and the light excluded is that which brings out the finest details in the standard image. This leads to — Propositions 3 and 4. When, of the light emitted by the object, only part is employed to form the microscopic image , then features may intrude themselves into the microscopic image which are not present in the standard image , and which do not represent anything upon the object ; and the partition of the light between the portions received by and excluded from the objective , will in general be different for different ivave-lengths ; and when the difference is marked, a colourless object will appear to be coloured in the Microscope. In connection with the use of the condenser we have — Proposition 5, The standard image is the outcome, partly of the features upon the object, and partly of the state of the light by which the object is illuminated. It may be improved by increasing the degree in which the first of those fac- tors, and by decreasing the degree in ivhich the second, contributes to produce, to modify , or to efface detail in the image. Proposition 6. Mounting the object in a medium of extra high refractive index will, cseteris paribus , increase the conspicuousness of the finer detail to be seen upon it. Proposition 7. If a microscopic object, mounted dry, is so close to the cover-glass that the chink of air between it and the cover-glass is less than the thickness of the Stokes's layer, then light from it can pass up through the cover-glass and the oil above it at angles both within and beyond the critical angle. The peculiar optical properties of a thin layer (Stokes’s layer) of a rare medium in contact with a denser were investigated by Sir George Stokes.* In the application of the above principles to the Microscope 'the author starts with the consideration of the illuminating apparatus. The source of light and the condenser are so far good as they enable the whole of the light of each wave-length which is brought to bear upon a point of the object to reach that point at each instant in the same phase- Efforts to attain this end should not be confined to the improvement of the condenser and to the cutting of thin sections. A further advance may be made by attending to the source of light, which ought to be confined to a thickness small compared with a wave-length. The appearance presented under the Microscope by the diatom Pinnularia nobilis is brought forward as an illustration of the confusion into which the light is thrown by traversing the substance of the object. Matters would be improved by mounting the diatom between two media, of which the under one has the same refractive index as silex, and the upper one- a refractive index as much as possible exceeding this. The successive stages of the transformation from the object to the image delineated on the retina (see fig. 2) are then carefully traced out. These stages are as follows : — A. Object A, the actual microscopic object, to which corresponds the * Stokes’s ‘ Collected Papers,’ ii. p. 5G. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. ideal image A, reproducing all possible detail, which only light of infinitesimal wave-length would be competent to produce. B. Image B, the standard image. C. Image C, standard image No. 2, is the image which the light taken in by the objective would, if reversed, produce. D. Image D, the focal image formed by the objective, is an enlarge- ment with distortion of image C. E. Image E, the visual image , is the virtual image formed by the eyc-piece, an enlargement with slight distortion of image D. F. Finally, image F is the image actually produced on the retina of the observer. Fig. 2. The consideration of the transition from A to B leads to the conclu- sion that any speck in the image, when best seen, will have an apparent diameter of A/4 ; consequently the corresponding portion of the object (viz. a globe with diameter A/4) contains an enormous amount of detail, all of which is massed together in the standard image as one speck. The investigation of the other transitions (from B to C and so on) shows that it is upon image C, the standard image No. 2, that we must fall back to determine what is the detail in the image E and its true nature ; and that the adjustments of the Microscope must be made with a view to the improvement of this image C. The course of an individual beam from this standard image C (fig. 2) is then traced. The dark line in the figure represents the axial ray. The beam is brought to a focus at x , then diverges and helps to form the image D, and after passing through the eye-piece is brought to a second focus at y , where the eye-piece can form an image of x. The light of the beam advancing in the direction qy will enter the eye as if it had come direct from the whole extent of the image at E. After passing y , the beam again diverges, but is bent by the action of the front half of the eye so as to again intersect the optic axis of the Microscope where that axis pierces the retina of the observer ; and there it assists in the forma- 74 SUMMARY OF CURRENT RESEARCHES RELATING TO tion of tlie image F. At x is formed the image which can be seen on removing the eye-piece. As regards the illumination of the object, the light from the iris- diaphragm and stops should be such as would be emitted in the reverse direction downwards from a perfectly featureless self-luminous plane occupying the position of the objective field. The ideal position for the iris-diaphragm and stops would be a position z (corresponding to x and y ) where beams of uniform plane waves emitted downwards from the supposed luminous plane would be brought to a focus by the con- denser. This position is very close to the condenser, and the author suggests that it would be a marked improvement in Microscopes if the iris-diaphragm and stops were brought nearer to this ideal position than is usually the case. A consideration of the composition and resolution of undulations leads to the following modification of Proposition 1 : — The whole of the light emitted from the objective field may be resolved into beams of uniform plane leaves; these beams may be divided into smaller groups , each an elementary sheaf of beams, and each elementary sheaf of beams may have a single beam substituted for it . According to the author, the great advantage of this Abbe method of resolution into plane waves is that it substitutes uniformity for that want of uniformity which exists in all other methods of resolution in just those places where we are unable to assign the law of this want of uniformity. Part III. of the memoir commences with a discussion of the Numerical Aperture, or, as the author prefers to call it, Grasp. Let c denote the medium between the cover-glass and the objective. Everything below the objective, except medium c which is to be extended downwards, may be supposed to be removed and replaced by image C (i.e. standard image No. 2, formed in medium c by two reversals of the light.) The Fir*. 3. light from C is resolvable into beims of uniform plane waves, each with its axial ray. If a and /3 (see fig. 3) are the angles which one of these rays makes with the optic axis at o and s, then by Lagrange’s theorem n sin a = M sin /3 , where M denotes the magnification, and n sin a is the aperture or grasp of the beam. The author represents the grasp by G (instead of the usual N.A.) in the case of the most inclined beam, whose axial ray can be caught by the objective, and by g in the case of any less inclined beam. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 75 In fig. 4 let o b and o V be the axial rays of two beams lying in the same meridian plane, Jcq the front of the objective, and o the middle Fig. 4. of image C. These beams, if reversed, will produce a ruling in image C, the spacing of which is given by the formula V = o- (sin a -j- sin a), where X' is the wave-length in c, . * . n X' = X (the wave-length in air) = cr (9 +’ CO I— I r— I 1-1 O o o CM O CO -*H a © © 3 ci - © !5 be bol c p T3 P >h'W c3 °,S to ©^ to 5 g © Sotf =4-1 o M — , • *g s a s §r?£ § J§ § S .2 H >>• * ‘ © © .3 r— ’ >>'5 _ o ft-±! -g P 53 a ^ c3ok©^.3©o ^ . s . r j -e « <=> ^ 05 CM Qom CM CM <#MNN0300KJ OCOOCOOOCCOC1 CC lO O ■>+• CM O I— I CM O © © O O COCOt'HH^ © © rt ■ . <3 §23- ^ c *1 o 02 •3 o tfl 2 So •o 1" c; C5 00 00 CO CO Q0 O o © © r9 5 Kj OT 3 W C-J 9 © g ^ o ^ © > .g _ , o!1-, « *-1 02 <3 O H CC i to g g! •-a - •g 02 -3 r© •P CO o Ci CO a aa © -£ . O g » *hQ 8 8 ^ p p j i ® o « H S w © -3 ‘ H 8 6 Ms- *2 © ps 2 CO ^3 ft' o( o3 . Q ? I s: <© 5> *$ o lO O o CO — < O o CC CO ^ a J ^<£ c3 -£ P 3 °1 o >2 © 4- © © ◄ •s bCcg *o J2 bo 2«« J3 ° *- n © c ■5 ’35 •+* K © CC .s a I* © ? I 94 PROCEEDINGS OF THE SOCIETY. Treasurer — William Thomas Suffolk, Esq. Secretaries — Prof. F. Jeffrey Bell, M.A. ; Rev. W. H. Dallinger, LL.D., F.R.S. Twelve other Members of Council — *C. Edmund Aikin, Esq., B.A., M.R.C.S. ; Conrad Beck, Esq. ; Alfred W. Bennett, Esq., M.A., B.Sc., E. L.S. ; Edward Dadswell, Esq. ; *R. G. Hebb, Esq., M.A., M.D., F. R.C.P. ; George C. Karop, Esq., M.R.C.S. ; *Prof. E. Ray Lankester, M.A., LL.D., F.R.S. ; the Hon. Sir Ford North; Thomas H. Powell, Esq.; Charles F. Rousselet, Esq.; Jolm Jewell Yezey, Esq.; Thomas Charters White, Esq., M.R.C.S., L.D.S. The President said he had one other matter of business only re- maining to be performed, and that was the very pleasurable duty of inducting the newly elected President, their old friend Mr. E. M. Nelson, and in so doing he felt that he was installing one who would fill the chair with great ability, and with great credit to the Society. Mr. E. M. Nelson, who was cordially received on taking the chair, said he sincerely thanked the Fellows for the honour they had done him in electing him their President, to occupy the chair that had been so ably filled by Mr. Michael during the past four years. It was usual at this point for the new President to adjourn the meeting until the next month ; but he proposed to depart from that custom, and to ask their kind attention to a few remarks on the present condition of the Society ; and begged their indulgence if he seemed to be too plain- spoken. He had no wish to pose as a pessimist ; nevertheless, he re- garded the present time as a very critical one in the history of the Society. There were difficulties ahead that would require very careful and skilful handling ; and it was because he firmly believed they might all be overcome, if the Fellows, when made acquainted with them, would only resolve to work together and support the Council, that he was addressing them in that way. The Balance Sheet which they had just heard read, though it gave a true statement of cash receipts and payments for the past year, did not really place them in a position to realise the present financial posi- tion of the Society. When he told them that, on the 31st of December last, there was owing to the Society a sum of nearly 500Z. for arrears of subscriptions, he felt sure they would agree with him that this was a most improper state of things. It was not in accordance with the dignity of the Society that this should be the case, neither was it fair to the Council, who were quite unable to meet their obligations (which amounted to a larger sum) without trespassing on investments which have been prudently put by in former years. A reference to the Balance Sheet would also show that a legacy left to the Society during the past year, which it would have been right to have treated as capital, had been absorbed in the year’s expenditure. Before proceeding further, he therefore appealed earnestly to the Fellows of the Society to remove the present anxieties of the Treasurer and Council by promptly paying their subscriptions, both due and overdue. * Those with an asterisk (*) had not held during the preceding year the office for which they were nominated. PROCEEDINGS OF THE SOCIETY. 95 It must next be pointed out that there were only fourteen Fellows elected last year — a number far below that of the resignations and deaths for the same period. It was therefore incumbent on them all to do their best to increase the present roll of Fellowship. He must also draw attention to the expenditure of the Society. The largest item, as they were well aware, was for the publication of the Journal. He believed it was considered that the Society’s Journal was unique among those of the other learned Societies ; for not only did it deal with Microscopical work proper, but it gave an abstract index of current Zoological and Botanical Literature. This entailed an enormous amount of work and expense, and he thought it was but right that the Fellows should know that the outlay on the Journal exceeded 900Z. per annum. One of the first and most pressing duties of the new Council would be to deal with that question ; and he thought it would materially assist them in their deliberations if the Fellows would express their views as to the value to them, as Microscopists, of the Journal in its present form ; that, however, he was asking on his own responsibility. He should like to state that his policy as President would be to endeavour, at all costs, to keep the Society’s expenditure well within its income ; and he felt sure he might confidently ask the Fellows to give their hearty support to the Council and Officers to carry out that course. On the other hand, he wished it clearly to be understood that, if the Fellows disapproved of the views he had expressed, and were not pre- pared to render their loyal support to such plans as the Council might decide upon to extricate the Society from its present somewhat difficult position, he trusted they would inform him, and allow him to vacate that chair at ^once, in favour of some one who would better represent them. He had only one more duty to perform, and that was to ask them to accord a very hearty vote of thanks to their old friend Mr. Michael, for the very able address with which he had favoured them that evening. In it he had touched upon both branches with which the Society was accustomed to interest itself, and it would therefore, no doubt, be read with great interest by all. He was very glad to hear Mr. Michael say that he was going still to be with them, because it was too often the fact that when a Fellow ceased to be President, they saw very little of him afterwards ; but, although Mr. Michael had made some allusion to his work as to some extent affecting his attendance, it was (he thought) very seldom that he had been absent from their meetings. Mr. Yezey said he should like to second the vote of thanks to Mr. Michael, whom he was afraid he must now call the ex-President ; and in doing so he would point out that the duties devolving on the President were not simply those of presiding at the meetings held in that room, but he was ex-officio Chairman of the Council, and in this respect Mr. Michael’s duties had been anything but light in the past year, and his wise counsel and guidance had been invaluable. Although, therefore, it was quite true that they cordially welcomed the new President, it was equally true that they parted from the late President with great regret. Mr. Michael felt he need not say more than that he thanked the Fellows present very heartily for the way in which his Address had 96 PROCEEDINGS OF 1HE SOCIETY. been received — as, indeed, they had always received everything lie had done for the Society during his period of office. The meeting was then adjourned. The following Instruments, Objects, &c., were exhibited: — • Mr. E. M. Nelson — An old Microscope, presented to the Society by Mr. James More, juu. ; a small Lamp for the Microscope, designed by Mr. Goodwin. Mr. Rousselet — Stephanoceros EiMorni, with fertilised resting eggs. New Fellows. — The following were elected Ordinary Fellows: — Mr. Sydney T. Klein, Rev. Fredk. Joseph Laverack, and Mr. James H. C. Steward. JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY. APRIL 1897. ■ - - MAY 14 1897 TRANSACTIONS OF THE SOCIETY. IY. — Presidential Address : Suggestions as to Points connected with the Microscope and its Accessories still needing Improvement. Resume of the Anatomy of Bdella. By A. D. Michael, F.L.S., &c. {Read 20 th January , 1897.) When, a year ago, your Council did me the entirely unexpected honour of asking me to he your President for a fourth year, I explained to them that, not having in any way anticipated such a request, I had undertaken about as much scientific work as I could manage to get through during the then coming twelve months ; and that therefore I was only able to accept the honour upon condition that they, and the Society, would be very indulgent to me in the matter of the Annual Address, for it would be impossible for me to devote as much time to its preparation as I had done in former years. Work of this class is apt to turn out more, not less, than we anticipate ; I fear, therefore, that what little I have to offer you to-night may be somewhat disjointed and less carefully worked up than the addresses of earlier years. Another reason for its being rather disconnected is, that this is the last occasion on which I shall occupy this chair as your President, and there are a few things which I should like to say to you before I leave it. The first of these is to thank you all for the unvarying kindness and courtesy which I have received from Council, Officers, and Fellows alike, from the first day of my presidency to the last. I shall always look back to the past four years with the greatest pleasure, and with gratitude to my fellow Members of this Society who have combined to render it pleasant. Next, I wish to make a few observations, which I hope may be of some little practical service, as to the Microscope itself and one or two of the articles which are frequently used in connection with it. These remarks will be directed entirely from the point of view of a constant worker with the instrument who feels the want of certain 1897 n 98 Transactions of the Society. things, not from that of the optician. All matters of scientific optics •will doubtless be dealt with by my successor, who is far more compe- tent to do so than I am. The optical construction of a Microscope has made vast strides during the last few years, and although I am not one of those who believe that perfection has been reached, or even approached, or that there is not any field left for improvements in the future, yet it must be admitted by all impartial minds which have been occupied with the subject that such field has been substantially diminished ; and it is also indisputable that the perfecting — or rather, improving, for nothing is perfect — of the optical combinations of a Microscope is by far the most important part of its construction, and has rightly claimed the greatest share of attention. But I am not sure that, while eagerly pursuing this subject of paramount impor- tance, and while rejoicing in such brilliant discoveries as homogeneous immersion and apochromatic lenses, we have not somewhat neglected other parts of the instrument, which might very well receive atten- tion in the lull after these great optical successes. It must be remembered that the finest gem is half wasted if badly set, and it must also be borne in mind that the perfecting of these lenses is only a means to an end ; that end is not only the examination of test objects and of objects requiring the highest powers of the instrument, nor of show objects; these are all matters of great value and of the highest interest ; but behind them is the supreme necessity of enabling the thousands of scientific workers who now use the Micro- scope as their everyday instrument of research to do their work in the best, the most convenient, and the quickest manner possible. Another element for consideration is that a large number of these investigators are not men of large means, who can afford to be continually pur- chasing new and expensive apparatus ; if they make an effort to buy it, it must wear well. Now I think that in the race for optical excellence and for low initial cost, the importance of some of these points has not been kept as rigidly before the eyes of makers and designers of Microscopes as it might advantageously have been. The first instance which I will refer to is the coarse-adjustment. This is of the highest importance, for it is used by the average of workers far more than the fine, and it is manifest that the most perfect optical arrangements are wasted if the coarse-adjustment of the instrument which supports them will not hold its focus. When our Microscopes come home from the makers’ hands they usually do hold their focus, and the coarse-adjustment works admirably ; but do they continue to do so ? My experience is that, as a rule, they do not. I am the possessor of several Microscopes, and my instruments are not put away in a glass case to be looked at or preserved ; they are pretty constantly used ; there is only one of them with which I have not had trouble over the coarse-adjustment, and that one is the oldest of them all, and has had quite equal work with the others during the shorter period they have been used in. I will not mention instru- Presidential Address. By A. ID. Michael. 99 ments nor makers’ names, but possibly some of my bearers will not be slow to guess what it is. The others have all ceased to hold the focus after a time, and although the tightening of the screws intended to remedy this will cure matters temporarily, it soon ceases to do so. Then the instrument goes back to the makers, and returns better, but not as good as it was at first, and the period for which it will retain its improvement gets shorter and shorter. Why is this ? It will be said, “ from the natural tendency of all things to wear out.” This is quite true ; but the oldest instrument does not wear out, or, at all events, only very little ; therefore I may repeat the question, Why is this ? Ami entirely wide of the mark in suggesting that possibly better workmanship and harder metal may have something to do with it ? It appears to me that in the struggle to reduce cost we forget the great importance of having the working parts made of the most enduring, and consequently, as a rule, the hardest, metal possible. The balance wheel of a watch has a pivot of the hardest steel pro- curable, and it rests upon something equally hard ; but have we followed this excellent example ? I fear not ; cost has come in the way, and although the pinion of our coarse-adjustment is usually, I imagine, made of steel, yet the rack is made of something, not only softer, but often very considerably softer. The harder metal naturally wears away the softer to some extent, and after a period of use the teeth or screw of the pinion which fell sweetly into the rack at first do not quite do so any longer ; then comes increased wear, and the evil goes on even faster than before ; moreover, it seems to me that diagonal racks wear as fast as straight ones. It is true that the rack may usually be replaced at some considerable expense and trouble, but it is desirable to avoid this if possible, and a good deal of incon- venience is usually put up with before deciding to change the rack. It is not the rack alone that wears ; the shaft that carries it wears away also, and the softer it is the faster it wears. Fine instruments are made commonly with the parts near the angles slightly project- ing, the central part being planed away. This is doubtless the best construction, but it does not wholly cure the evil unless the metal be very hard and highly finished ; the projecting part wears, and what is worse, it wears unequally. At least nine-tenths of each man’s work is usually upon a small part of the rack, according to the objectives he most frequently uses, and the parts which receive the pressure when the Microscope is in this position wear most. There must always be a portion of the shaft and rack which is above the collar of the stand when the instrument is in use, and therefore does not wear at all ; thus the projecting angles, although they project equally all the way along at first, gradually cease to do so ; this is a much worse evil than the rack, for it produces an uneven motion and a difficulty in holding the focus ; and these angles are usually of the same piece of metal as the shaft itself, and cannot be replaced. It seems to me that where these projecting angles exist, as it is desirable that they should do, they might h 2 100 Transactions of the Society. be removable like the rack and be replaced when worn. I am aware that there are certain difficulties of fitting, but with care and good workmanship these may be overcome. It will be said that the collar through which the shaft passes may be, and usually is, sprung ; that is doubtless an advantage, but my experience is that it is not entirely a remedy. Again, it will be said that every Microscope has tighten- ing screws to meet this very difficulty ; so it has, and very admirably they act the first time they are used ; but afterwards something wears away ; if the screw be of harder metal than the shaft, or whatever it presses on, it gradually cuts a little channel, and that channel is cut in the place where it touches when the Microscope is at the elevation at which it is most frequently used ; so that the instrument will hold its focus beautifully in every position except the one in which its owner requires to use it. I suggest that these screws should be of much softer metal than what they press upon, so that they may wear away instead of wearing it, and that a few duplicate screws should be supplied with each Microscope, which could be substituted when the original ones are worn out ; and they might well have some mark on the outside to show when they have been inserted to the extent of their capacity, and are no longer useful. The moral of all this is that the coarse-adjustment is as important as it ever was ; and that hard metal and good workmanship are not less valuable to-day than they were years ago, and are worth paying something to obtain. There is, however, another aspect to this matter; and I venture to ask a question which I fear many of my hearers will consider rather a wild one ; namely, Is it absolutely necessary that the whole weight of the movable part of the instrument should be borne by the coarse-adjust- ment ancl the tightening screws ? Is it beyond the power of human ingenuity to find some satisfactory method of supporting that weight without having recourse to pressure on the faces of the shaft ? Can- not we hope for the time when all the coarse-adjustment will have to do will be gently and evenly to move parts the weight of which is supported or balanced by other means ? I do not see that it is impossible, and it seems to me to be well worthy of the careful consideration of constructors ; the Wale stand was an ingenious step in this direction, but failed for want of rigidity, &c. If we could attain this end we might then indeed have an absolutely efficient coarse-adjustment which practically would not wear out. The next point which I wish to mention is the working distance afforded by the objective. I fear that in the struggle for definition this is a good deal lost sight of ; it is quite true that with high-power objectives, by which, for this purpose, I mean everything above a quarter of an inch, if one has distance enough for the object and the medium, if any, which it is immersed in, and the cover-glass, that is all that is requisite ; unless indeed we could obtain sufficient distance to use reflected light with high powers, of which there does not appear any immediate prospect ; but the requirements of modern ana- Presidential Address. By A. D. Michael. 101 tomy and research are daily becoming greater, and notwithstanding the immense assistance obtained from section-cutting it continually becomes more and more important to work upon very minute objects under a Microscope. To meet these requirements there should be objectives of half-inch focus, under which a knife or other instrument can be freely used ; but how few there are, and they are rather diminishing than increasing ; it is true that they would not probably give the definition which is obtained by objectives which have less working-distance, but there is ample field for both ; and a serious effort should in my opinion be made to produce half-inch objectives with more working distance than is possessed by most of those at present supplied, combined with the best possible definition which can be obtained at that distance. The effort should not cease here ; human skill persistently directed to a desired object does many things, and I trust that the time may come when we may be able to dissect under higher powers than a half-inch. It is true that apochromatic lenses and compensating eye-pieces have done a good deal for us in this connection ; for they have enabled us to use deeper eye-pieces, and consequently lower objectives, to obtain the same amplification ; but these eye-pieces, excellent as they are, have some disadvantages, among which is not being very suitable for the Stephenson binocular, which is, in my opinion, still facile 'princess among dissecting instru- ments. The next point is one which I have mentioned before from this chair ; namely that in these days when section-cutting is one of the greatest, if not absolutely the greatest, means of biological research, and when we are anxious as far as possible to mount a whole series of sections on one slide, it is most desirable to have a good mecha- nical stage that has a motion of 3 in. by 1 in., or very close to that measurement. Only those who themselves use serial sections to discover what was previously unknown can thoroughly grasp the importance of this ; serial sections are not a book which everyone who runs may read ; in minute and complicated anatomy the information is there, but it is written in a language which it requires the closest attention to understand ; the eye and the mind have to follow the individual organ which is being traced from section to section, often through a great number of sections, and preserve clearly in the mental vision the result of the combination of these numerous and varying pictures. The continual shifting from row to row of sec- tions, or worse still from slide to slide, distracts the attention, and interferes seriously with the powers of realising the results ; therefore the longest mechanical movement of the stage is of substantial impor- tance ; and it is equally important that whatever movement there is shall be capable of being exerted without bringing any part of the apparatus up against the substage condenser and upsetting that. Since I called attention to this subject before, two very ingenious arrangements have been brought forward with a view to remedy the 102 Transactions of the Society. defect — one by Messrs. Swift, the other by Messrs. Zeiss ; but although these are great improvements they do not quite overcome the difficulty, and I urge upon those gentlemen and other makers and designers not to relax their efforts before complete success is obtained. Until that success arrives the inconveniences may be somewhat modified by a very simple contrivance, which, however, is rarely met with on our Micro- scopes. It is so simple that one hardly likes to mention it here, and yet it is very helpful. The slide should (and usually does) rest upon a sliding bar at the proximal side of the stage ; for the old plan of resting it on two pegs, so that when the end of the slide has passed one peg the slide tumbles off the stage, is now, I hope, happily superseded. At the left end of this sliding bar is a stop, which is most useful — indeed, almost essential — for measuring, finding, drawing, &c. ; but this stop prevents the slide being pushed on with the fingers when the move- ment of the mechanical stage is exhausted, before the end of the line of sections is reached. If this stop be hinged, and capable of being turned downward through an angle of 90 degrees, so that instead of being at right angles to the bar it forms an extension of it, the slide can be pushed along this extension, and the remainder of the row of sections seen. Of course, it is far inferior to a mechanical stage which will travel the whole distance, but it is a good deal better than nothing. The stop should have a little spring to cause it to stand firmly in these two positions and not between them. Anyone who has worked with this simple contrivance will appreciate the comfort of it as stages now exist. Another matter that I think does not receive as much attention as it might do in our Microscope-stands is the revolving stage. It is known how convenient it is for it to revolve right round; but this is very often neglected, or sacrificed to other things, and great * inconvenience is caused thereby. It does not usually matter very much while we are simply examining an object ; but when we come to draw it, we frequently find that we cannot turn the stage far enough to get it into the right position. Then the slide must be taken off* the stage and reversed, the object re-found, and the instru- ment re-focused (not without some danger of injury if the object be unmounted) ; and, after all, we perhaps find that we are not any better off, because the right position is just ’ that small piece of the circle which the stage will not pass, whichever side it be turned from. Another thing which, it seems to me, is too frequently neglected, is allowing sufficient space between the substage and the table for the mirror to be turned at any requisite angle when the Microscope is upright. And it is desirable that we should be able to turn it with- out (if we are using the flat mirror) reflecting the image of the milled heads of the apparatus which focuses the substage condenser, and throwing it on to the object. It is true that we can get rid of the image by turning the mirror ; but that limits the power of searching Presidential Address. By A. B. Michael. 103 the sky for a good light when working by daylight. The zenith is often blue, and the best light is often found not very far from the lowest part of the sky visible ; but it is exactly in this position that we get the image. It would be convenient if the milled heads could revolve out of the way, and I think it might be done. Now a few words about some articles which, although not part of a Microscope, are often used with it. We are extremely careful to achromatise our substage condensers : why should we not do a little in the same direction for our stand-condensers ? The two cases are not altogether similar, and the latter is far less important ; but I fancy that something might advantageously be done more frequently than it is. Then there is the question of knives. No knives are manufactured for microscopical work ; the ordinary scalpels sold are utterly unsuited for microscopical purposes. The finest knives that one can buy are those made for oculists ; but even these are much too coarse for delicate microscopical work. It might be worth while for the makers of Microscopes to see if they cannot get some knives made fit to use with them. Then knives want sharpening. Good dissect- ing— and, to an even greater degree, good section-cutting — depends greatly upon the sharpness of the knife and the smoothness of its edge. Probably the best thing we have for sharpening is an Arkansas stone ; and something may be done by using soap instead of oil ; but might we not possibly manufacture something of even finer grain ? Of course, I am not alluding to finishing-strops. Finally there are lamps. These have received a good deal of attention, but still I fancy there is much room for improvement. A lamp otherwise well manu- factured, frequently — perhaps I might say usually — has a badly made and flimsy burner ; and it is desirable to be able to get the image of the flame without the image of the metalwork overlapping it when the lamp is some distance above the mirror. Sufficient care is not always taken to prevent the paraffin from sucking up by capillary attraction and spreading all over the outside of the reservoir, &c. ; and in lamps with metal chimneys, there should be some simple means of taking the chimney off while the lamp is alight without burning one’s fingers. The chimney should be left off until the lamp is re- lighted, which greatly diminishes the unpleasant smell otherwise arising upon lighting it. I propose to occupy what little time remains to me in giving you a very brief resume of some portions of the microscopical work which has occupied most of my time during the last three years. The re- sults were laid before the Linnean Society in April last, and have just appeared in their Transactions ; but, as the greater number of our Fellows here do not belong to the Linnean, and had not the oppor- tunity of hearing them there, they may take some little interest in doing so now ; particularly as, when last year I addressed you on the anatomy of the Acarina, I was obliged, in justice to the Linnean Society, to be wholly silent respecting that of the Bdellinae, which 104 Transactions of the Society. was the subject of the paper to he laid before them, and in which (as it had been very little investigated before) I was able to make a few discoveries, I hope of rather more than passing interest. The first point which I will mention is the construction of the pharynx, which is the great sucking organ in such Acari as live by suction ; and the principal interest in what I am about to mention lies, I think, in showing how small a variation will sometimes profoundly affect the action of the parts. In order that you may understand this variation in BdeJla, I will shortly remind you of what the pharynx usually is in allied families, such as the Hydrachnidae. Imagine two chitinous half-tubes, like the gutter-pipes round roofs, fitting one inside the other, and soldered at the edges, the lower one fixed, the upper slightly flexible, so that it can be raised by perpendicular muscles. When the roof of the pharynx is so raised, a partial vacuum is left between it and the floor ; the food rushes in from the mouth ; a valve closes the entrance of the pharynx ; then some transverse muscles, which run from one upper edge of the half-tubes to the other, contract, driving the upper half-tube down on the lower, and consequently (as the opening to the mouth is closed) driving the food on into the ventriculus. In Bdella the variation is that the roof of the pharynx is not chitinised ; consequently the muscles would not raise the whole roof, hut each muscle would raise only the piece it was attached to. Therefore a new arrangement is made : the muscles, in- stead of acting together, act successively, and the food is carried back by the undulation produced, much as in a cat’s lapping. Then the transverse muscles, if attached to the upper edges as in other cases, would not force the upper half-tube down, they would simply crumple it ; therefore they have the ends attached below the pharynx, and pass in an arch over it, so that when they straighten, also successively, they compress the whole pharynx, and restore it to its original condition. The pharynx passes into the oesophagus, which in all known Acarina, except Bdella, is a mere straight tube. In Bdella alone, I have dis- covered that at the oesophageal end of the pharynx there is a ring- constrictor muscle, and immediately behind this ring the oesophagus bifurcates ; one branch is the ordinary tube to the ventriculus, the other leads into a large blind sac at the end of the tubular stalk, and this sac is a reservoir in which food is stored before passing into the stomach. The interest of this, to my mind, lies not in the arrangement itself, but in the fact that it is unknown amongst other Acari, and even, as far as I remember, amongst other Arachnida, while it is well known in a totally different class of the Arthropoda, namely the Insecta, where it is common amongst Diptera, Lepido- ptera, Hymenoptera, Ac. How are we to account for the sudden reappearance of this organ in one solitary genus so widely removed from those groups where it is typical ? Are we to suppose that a common want has produced a similar development in both cases ? But if so, how is it that none of the other sucking Acari have it, and 105 Presidential Address . By A. D. Michael. that it is not found in Spiders or Phalangiidae ? Or are we to go back to some common ancestor, which we suppose to have had the organ, which has lain dormant in all the numerous stages over vast periods of time, until Bdella was reached, and then suddenly reap- peared in full vigour? Or are we to suppose the Acarina to be derived from the Insecta ? If so, where is any trace of the organ in the intermediate stages, and why does it die out suddenly after Bdella without there being a trace of it in the most nearly allied creatures ? A very pretty little piece of apparatus which is peculiar to Bdella, although structures serving a similar purpose are known elsewhere, is the epipharynx. This is an organ which is somehow much neglected by anatomists, both in Insects and Arachnida, and yet it is of con- siderable interest, and of some importance. Oddly enough, it is frequently called the “ lingua,” although the two organs often co-exist in the same creature, and although a true lingua arises from the door of the mouth below the pharynx, while the epipharynx, as its name implies, is above the opening of the pharynx, and in the Acarina usually springs from the anterior upper edge of the pharyngeal tube, and projects freely into the mouth-cavity, forming a kind of pent-house overhanging the entrance to the alimentary canal, and probably guiding the food into the opening. It is usually a stiff, more or less elongated, lanceolate or triangular blade ; the latter is the shape in Bdella, but from its sides in that creature a broad membranous border hangs down like a curtain at the side of the food-stream. It must be remembered that Bdella is a predatory creature living by suction, and is a member of that group of Acari where no certain connection has been found between the ventriculus and the hindgut. It does not appear to pass solid dejecta, and therefore it is important that none should enter the canal. This is effected in the Acari of this genus which I have dissected by the epipharynx in the following manner. The lancet-shaped piece with its membranous edge is not the whole of the apparatus ; some little way below it is a thin horizontal semi- lunar membrane with its convex edge forward ; its upper surface and its curved edge bear regular series of teeth like those of a saw. The membrane is very transparent, and quite flexible, so that in its ordinary position it falls downward, making the upper surface the anterior, and of course, presenting the teeth towards the mouth. The largest teeth are at the edge ; they fall in front of the opening of the pharynx, and their points fall between a set of minute wart-like ele- vations on the floor of the mouth ; thus a grating is formed which effectually strains all solid particles out of the fluids which are sucked into the pharynx. The brain in Bdella has a peculiar interest for the following reason. When last year I showed you a picture of the almost globular brain of one of the Hydrachnidee, w7ith the nerves springing from it, and the small round hole in the centre affording a passage for the oesophagus right through it ; and when I told you at 106 Transactions of the Society. the same time that that nearly spherical mass had been derived from distinct supra- and subcesophageal ganglia, you might well he excused if you felt somewhat incredulous. My mouth was then closed as to the anatomy of Bdella, a creature of a closely allied sub-family ; now I am able to show you a drawing of it carefully made from actual dissections. You will see here that the large sub-oesophageal ganglion is a flattened, almost oblong, sheet of nervous matter, with the actual nerves penetrating far into it in plainly discernible courses ; while the small, almost cubical, supra-oesophageal ganglion is perched on the anterior end of the lower ganglion, and is sharply demarcated from it. Both are slightly excavated for the passage of the oesophagus between the two. We should be inclined to say from this that Bdella was a primi- tive form amongst Acari, and one of the nearest to other groups such as the Insecta, from a phylogenetic point of view, but the result of further inquiries into the anatomy of the creature shows how difficult such tracings of phylogeny really are, and how complicated are the questions that arise during the inquiry ; and we may also learn how easy it is to draw up phylogenetic trees if we confine our attention to the particular organs which we are thinking of at the time, and how delusive those trees may be when so drawn up ; for in spite of the somewhat primitive character of the brain in Bdella, as compared with that in most other Acari, some other systems of organs in this animal are far more specialised and complicated than the correspond- ing parts in any other known Acarine ; I think I might say, than those in any other known Arachnid. These highly specialised portions of the anatomy are the male genital organs and the salivary glands. The great size, variety, and peculiarity of the latter are very remarkable, while the complication of the former, and the variety, size, and unexpected and special characters of the numerous accessory glands and other organs included in them are really quite startling. I wish I had time to describe to you even a few of the many inter- esting features of those organs, but it would be hopeless to attempt to do so to-night ; anyone interested in them will find them described in the Transactions of the Linnean Society. And now I have only to thank you once more for the unfailing courtesy and kindness which I have received at your hands during my long occupation of this chair, and to bid you farewell as your President, although I hope to remain for many years one of those connected with your Society in a humbler capacity. SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY (principally invertebrata and cryptogamia), MICBOSCOPY, Etc. Including Original Communications from Fellows and Others.* ZOOLOGY. VERTEBRATA, a. Embryology, f Germinal Selection.^ — Prof. A. Weismann in tliis important essay seeks to remove “ the patent contradiction of the assumption that the general fitness of organisms, or the adaptations necessary to their ex- istence, are produced by accidental variations — a contradiction which formed a serious stumbling-block to the theory of selection.” “ Though still assuming that the primary variations are ‘ accidental ,’ I yet hope,” he says, “ to have demonstrated that an interior mechanism exists which compels them to go on increasing in a definite direction the moment selection intervenes.” In this sense definitely directed variation exists. The interior mechanism referred to is germinal selection, i.e. the selection of vital units within the germ-cells ; and the central idea of the essay is that “ the variations presented to personal [better individual or organismal ?] selection must themselves have been produced by the principle of the survival of the fit.” This is effected by profound processes of selection in the interior of the germ-plasm. In short, Weismann has extended to the determinants in the germ the conceptions of struggle, elimination, and survival. With his usual adherence to logic he has extended Roux’s “ struggle of parts ” and histonal selection to the farthest possible point. A few quotations will make his position clear. * The Society are not intended to be denoted by the editorial “ we,” and they do not hold themselves responsible for the views of the authors of the papers noted, nor for any claim to novelty or otherwise made by them. The object of this part of the Journal is to present a summary of the papers as actually published , and to describe and illustrate Instruments, Apparatus, &c., which are either new or have not been previously described in this country. f This section includes not only papers relating to Embryology properly so called, but also those dealing with Evolution, Development and Reproduction, and allied subjects. t ‘ On Germinal Selection,’ Chicago, 1896, 8vo, xii. and 61 pp. ; C. R. Congr. Internat. Zool., 1896, pp. 35-70. 108 SUMMARY OF CURRENT RESEARCHES RELATING TO “A part is not only nourished but also actively nourishes itself, and the more vigorously, the more powerful and capable of assimilation it is. Hence powerful determinants in the germ will absorb nutriment more rapidly than weaker determinants. The latter, accordingly, will grow more slowly, and will produce weaker descendants than the former.” “ Minus variations repose on the weaker determinants of the germ, that is, on such as absorb nutriment less powerfully than the rest. And since every determinant battles stoutly with its neighbours for food, that is, takes to itself as much of it as it can, consonantly with its power of assimilation and proportionately to the nutrient supply, therefore the unimpoverished neighbours of this minus determinant will deprive it of its nutriment more rapidly than was the case with its more robust ancestors ; hence it will be unable to obtain the full quantum of food corresponding even to its weakened capacity of assimilation, and the result will be that its descendants [“ ancestors ” in the translation] will be weakened still more. “As soon as personal [individual] selection favours the more power- ful variations of a determinant, the moment that these come to predomi- nate in the germ-plasm of the species, at once the tendency must arise for them to vary still more strongly in the plus direction, not solely because the zero-point has been pushed further upwards, but because they them- selves now oppose a relatively more powerful front to their neighbours, that is, actively absorb more nutriment, and upon the whole increase in vigour and produce more robust descendants. From the relative vigour or dynamic status of the particles of the germ-plasm, thus, will issue spontaneously an ascending line of variation, precisely as the facts of evolution require.” “ Thus, I think, may be explained how personal selection imparts the initial impulse to processes in the germ-plasm, which, when they are once set agoing, persist of themselves in the same direction, and are therefore in no need of the continued supplementary help of personal selection, as directed exclusively to a definite part.” There is much else in the essay which deserves careful attention, — the general vindication of the selection-principle, the modification of his theory of panmixia, the apology for hypotheses, and so on, but in our limited space we have thought it better to give prominence to the main idea. Evolution on Definite Lines.* — Prof. G. II. Th. Eimer delivered a lecture on this subject at the International Congress in Leyden, which may be fitly noticed in connection with Weismann’s. Two more anti- thetic utterances it is difficult to conceive. Orthogenesis, or progressive variation in definite direction, is a fact : and a fact destructive to Darwinism. The causes of orthogenesis are to be found in the action of environ- ment upon the constitution of the organism. Evolution is a larger aspect of growth. The facts of orthogenesis lead us to recognise certain laws of evolution, of which Eimer states ten, as in his book. The origin of species depends not on selection, but (1) on stoppage (Genepistasis) at given stages in the evolution-process, (2) on saltatory * CK. Internat. Congr., 1896, pp. 145-69. ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 109 evolution or halmatogenesis, (3) on reproductive isolation (Kyeamechanie), as Eimer pointed out in 1874. Prof. Eimer gives concrete illustrations of liis position, and criticises Weismann’s. We cannot, however, enter into the discussion, interesting as it is ; the antithesis, roughly stated, is that to Eimer almost every- thing depends upon growth, to Weismann almost everything depends upon selection ; but it is perhaps more accurate to say that there is no antithesis, only a difficulty in appreciating the relative values of the two. Problems of Vertebrate Embryology.* — Dr. J. Beard has followed up his more concrete and technical papers with a general essay on some problems of Vertebrate embryology. The thread uniting its different parts is the idea of a substitution of organisms in Vertebrate ontogeny. He begins by stating the characters of “ the critical stage ” in Elasmobranch fishes. The embryo is beginning to show definite adult characters, and at this stage it annexes (into the gut) the external yolk- sac. In other Ichthyopsida, the critical stage is also found — nay more, all through up to Mammals. Thus the author points out most suggestively the correspondence of the critical stage in Scyllium with the birth-period in Didelphys , when, as before, a new mode of nutrition is initiated, and with the 15th day stage in the rabbit’s development, when the change to an allantoic placenta is realised. Valuable tables at the end of the essay make it easy to compare a variety of types at their critical stage. The author states von Baer’s laws, so often misstated, and would replace them by the following : — “ There is a stage [the critical stage] in the development of every Vertebrate embryo, during which, and only then, it resembles the embryo of any other Vertebrate in a corresponding stage in certain general features. But, while it thus agrees exactly with any other embryo in this stage in characters which are common to all Vertebrate animals, it differs from the embryo of any other class in certain special class-features, and also from any other embryo of the same class but of a different order in other and ordinal characters. Immediately before this stage is reached, it begins to put on generic and specific characters, and thus it then begins to differ from all other embryos in these.” “ The whole of this has its explanation in an antithetic alternation of generations as underlying the development ; for it is the stage at which the embryo first has acquired such an independence as will enable it to set about the task of suppressing the larval or asexual foundation, the phorozoon.” The Recapitulation Doctrine.f — Prof. F. Houssay has been prompted by Dr. Beard’s results and theories to discuss some aspects of ontogenetic recapitulation. While very appreciative of Beard’s work, he has some criticisms to make. The most important propositions are the following : — (1) The idea of “ a substitution of organisms ” (Beard) does not exclude a modified belief in ontogenetic recapitulation of phylogenetic stages ; (2) Beard has tended to confuse (in part, deliberately) the conception of alternation of generations on the one hand and of metamorphosis on the * ‘ On Certain Problems ofVertebrate Embryology,’ 8vo, Jena, 189G, vi. and 77 pp. t Anat. Anzeig., xiii. (1897) pp. 33-9. 110 SUMMARY OF CURRENT RESEARCHES RELATING TO other ; (3) alternation of generations is “ a fragmentation of the indi- vidual,” a division of the specific individuality into two stages ; (4) meta- morphosis or metahole is the result of a diminished vitality in ontogeny, of a period of local asphyxia, and is associated with phenomena of necrobiosis ; (5) what Beard regards as an alternation of generations in Vertebrata seems to Houssay rather a metabole. It may be noted that this paper does not take account of Beard’s paper summarised above. Development of Teeth in Perameles.* — Prof. J. T. Wilson and Mr. J. P. Hill base on their observations on the development of the teeth of this Marsupial a simpler view of the dentition of these animals than that now in vogue. They regard the permanent teeth of Marsupials as the homologues of the permanent or replacing teeth of other Mammals. They find the deciduous premolar to be a true milk-tooth, while the so-called prelacteal teeth are in reality milk-teeth which have undergone reduction. The lingually situated downgrowths of the dental lamina by the sides of the developing teeth are not rudimentary enamel-germs. They are merely portions of a quite indifferent “ residual dental lamina ” ; the swelling of the distal portion exhibits no differentiation which is really characteristic of actual enamel-organs. Experiments on Growth of Blastoderm of Chick. + — Mr. R. Assheton set himself to test by actual experiment Duval’s theory of the formation of the primitive streak, and to try and determine experimentally whether the whole or only part of the actual embryo is developed by the activity of the primitive streak. The result of the first set of experiments seemed to be that the primitive streak is not formed from the posterior edge of the blasto- derm, as Duval maintains. It further seems clear that all the parts of the chick in front of the first pair of mesoblastic somites (that is, the heart, brain, olfactory, optic, and auditory organs and foregut) are developed from that portion of the blastoderm which lies anterior to its centre, while all the rest of the embryo is formed by the activity of the primitive streak area. Proportions of Yolk, Albumen, and Shell.J — Hr. R. W. Bauer continues his painstaking estimation of the proportionate weights of yolk, albumen, and shell in birds’ eggs. In Columba romana, the yolk weighed 4*967 gr., the albumen 15*648 gr., the shell 3*355 gr. ; or, in percentages, 20*72, 65*29, and 13*99 respectively. Blastopore of Chelonia.§ — Prof. K. Mitsukuri, in this part of his contributions to the embryology of Reptiles, treats of the “ fate of the blastopore, the relations of the primitive streak, and the formation of the posterior end of the embryo in Chelonia, together with remarks on the nature of mesoblastic ova in Vertebrates.” The author has made a study of the surface changes and of what may be seen in sections of Chelonia caouana , Clemmys jajoonica, and Trionyx japonicus. He is led by his investigations to suggest a reclassi- fication of the eggs of Vertebrates : — * Quart. Journ. Micr. Sci., xxxix. (1897) pp. 427-588 (8 pis.). t Proc. Roy. Soc. Lond., Ixi. (1896) pp. 349-56 (5 figs.). % Biol. Centralbl., xvi. (1896) p. 848. § Journ. Coll. Sci. Imp. Univ. Japan, x. (1896) pp. 1-118 (11 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. Ill I. Primary Type. Archi-holobastic — Amphioxus. Proto-holoblastic — Eggs that have never acquired a large yolk-mass, and hence have retained the primary condition nearest to Amphioxus — Cyclostomi. Proto-mesoblastic. (a) Eggs that have acquired a large primary yolk-mass — Elasmobranchii. ( h ) Eggs that, having lost the large primary yolk-mass, have retained the mesoblastic mode of segmentation — Teleostei. Meso-holoblastic. — Eggs that had a large yolk-mass, but have returned to the holoblastic condition — Amphibia (?). II. Secondary Type. Meta-mesoblastic. — Eggs that, having had a large primary yolk- mass, have lost it and now reacquired it — Reptilia, Aves. Meta-lioloblastic. — Eggs that have passed through the pre- ceding stage, but again lost the yolk-mass, and returned to the holoblastic mode of segmentation — Mammalia. Reproduction and Development of the Common Eel.* — Prof. G. B. Grassi has made a series of most interesting observations on the life- history of Anguillula vulgaris. Four years of continuous research have enabled him to dispel the great mystery which has hitherto surrounded the reproduction and development of this common fish. That which has hitherto been known as Leptocephalus hrevirostris is the larva of the eel. The eel spawns in the sea, and the eggs float ; maturity is reached in the depths of the sea. Herr K. Knauthe f remarks that light is beginning to dawn on the “ eel-question,” and that it might soon be clear if the zoologist would make friends with the fisherman. In 1894, Herr A. Feddersen declared that the broad-nosed eel was resident and capable of reproduction in Swedish lakes. Herr Knauthe maintains that the same may be said for Brandenburg and elsewhere. He regards the land journeys of May and June as certainly reproductive in aim, and cites some cases which it seems difficult to interpret, except on the theory that reproduction may occur in fresh water. Life-Histories of British Fishes.J — Prof. W. C. MTntosh treats of the spawning of the lesser sand-eel, the eggs and young of the Pollack, the life-history of the Lumpsucker, the eggs and young of the bimacu- lated Sucker, and the life-history of Cottus scorpio. A number of useful details are given, but there are no generalisations of any kind. Essen- tially the same results are reported on elsewhere.§ £. Histolog-y. The Cell in Development and Inheritance. || — We cannot do more than call attention to this work by Prof. E. B. Wilson. The author * Quart. Journ. Micr. Sci., xxxix. (1896) pp. 371-85 (4 figs.). t Biol. Centralbl., xvi. (1896) pp. 847-8. % Ann. and Mag. Nat. Hist., xix. (1897) pp. 241-61. § 14th Annual Kep. Fishery Board for Scotland, pt. iii. pp. 171-85 (1 pi.). j| New York and London, 1896, 8vo, xvi. and 371 pp., 142 figs, in text. 112 SUMMARY OF CURRENT RESEARCHES RELATING TO acknowledges liis indebtedness to Prof. Oscar Hertwig’s “invaluable book,” but tbc rapid advance of discovery bas made it seem desirable to amplify tbe original plan of the work. It does not profess to be an exhaustive account of the cell, but to consider those features that seem more important and suggestive to the student of development. The author fears that the botanists will complain of gaps. Prof. Wilson concludes with a glossary, which will not only be useful to those who have forgotten their Greek, but to the student of the history of the subject, as in nearly all cases the name of the author of the term and the date of its invention aro added. Blood of Lamprey.* * * § — Dr. E. Giglio-Tos finds that the red blocd- corpuscles of the lamprey are unusually simple, like young stages, in fact. They are spherical vesicles, filled with haemoglobin in sparse cytoplasm. They are derived from erythroblasts, within which haemo- globin-forming granules — of nuclear origin — appear as usual. The erythroblasts in circulation show no indirect division, but in rare cases may divide directly. The erythrocytes do not divide. Leucocytes with simple nucleus and leucocytes with polymorphic nucleus arise from similar leucoblasts, which multiply by direct division. The fine “neutrophilous” granulations of the leucocytes with poly morphic nuclei are probably of nuclear origin. The amitotic nuclear division of these adult leucocytes is not followed by cell-division. New Nerve-Sheath.^ — Dr. A. Ruffini describes in the terminal tract of peripheral nerve-fibres a new sheath — the subsidiary sheath — which occurs between Henle’s sheath and Schwann’s. Centrosomes and Attraction-Spheres in Leucocytes of Newt.i — Dr. R. Marchesini finds that the centrosome and its attractive sphere have a quite definite form and occurrence. Even in the resting cell they have a direct relation with tbe nucleus, and may perhaps be regarded as a differentiation of the same. He believes that they not only preside over division, but have to do with plasmic movements and the nutrition of the cell. By using a mixture of malachite and saffranin greens he was able to differentiate the centrosome and its sphere instantaneously while the cell was still living. Minute Structure of Ganoid Scales.§— Dr. H. Scupin has studied the scales of a large number of fossil Ganoids. His chief results are the following : — The enamel is no necessary component of the Ganoid-scale, and may be absent in otherwise typical Ganoids. The interpretation of the “ lepidine tubes ” of Williamson as traces of connective tissue fibrils is confirmed. In the various families of Ganoids the minute structure of the scales is usually characteristic. The degeneration of the enamel in the Rhynchodontidae makes it necessary to separate this family from the others included in the sub-order of Lepidosteidei ; the nearest relations are rather with the Saurodontidae. * Mem. R. Accad. Sci. Torino, xlvi. (1896) pp. 219-52 (1 pi.), f Anat. Anzeig., xii. (1896) pp. 467-70 (1 fig.), t Boll. Soc. Korn. Stud. Zool., v. (1896) pp. 89-96 (1 pi.). § Arch. f. Naturges., lxii. (1896) pp. 145-86 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 113 y. General. Natural Selection and Separation.* — Mr. A. E. Ortmann attempts to show that only separation can effect differentiation of species. He thinks we should distinguish four factors — (1) all organic beings vary ; (2) these variations may be transmitted to descendants ; (3) upon the material produced by variation and inheritance there acts Natural Selection. But (4) Natural Selection does not form species ; it only preserves or transforms already existing species. “ Different species are formed by bionomic separation ; separation does not always imply differentiation of the conditions of life, and accordingly does not always form new species ; but if there is a differentiation into species it is always due to separation under different bionomic conditions.” Specific Characters.! — Prof. R. Meldola, in his annual address to the Entomological Society of London, took occasion to discuss the utility of specific characters and physiological correlation ; dealing, that is, with a question which was the subject of lively discussion during the year 1896. Prof. Meldola’s object was to suggest that physiological correlation may profitably form the subject of experimental investigation. He very justly remarks that, at present, discussions as to which out of a group of correlated characters is to be regarded as the cause of the survival of a living being are likely to prove barren. His hope is that his remarks may bring about a closer rapprochement between systematists and physio- logists. Nocturnal Protective Coloration.* — Prof. A. E.Verrill points out that very little attention has been paid to the colours of animals, as seen by twilight, moonlight, and starlight. Yet many animals only move by night, and those that roost in trees, bushes, or reeds need to be protected against their foes. When looked for, it is expected that instances of nocturnal protective coloration will be found to be numerous. The author cites a few examples, and concludes that the colours have been acquired by natural selection in consequence of the protection that they afford. Explorations in the Moluccas and in Borneo. §— Prof. W. Kfiken- thal has much to record concerning his visit to tho Malayan region in- 1893-94. The detailed description of the collections made will be given in special monographs ; the first part is a general Beisehericht. The plankton of the Indian Ocean was studied during the voyage. Careful observations were made of the flying-fishes, and led to the con- clusion that they do move their pectoral fins a little, but only so as to alter their course. In the littoral region of Ternate, three zones were well marked : — (1) The region of coral reef and sea-grass, very rich in species, but less thickly peopled than the arctic littoral region ; (2) the almost lifeless * Proc. Amer. Phil. Soc., xxxv. (1896) pp. 175-92. t Trans. Entomol. Soc. Loncl., 1896 (1897) pp. lxiv.-xcii. f Amer. Jouru. Sci., iii. (1897) pp. 132-4. § ‘ Ergebnisse einer zoologischen Forschungsreise in den Molukken und in Borneo.* I. Reisebericht. Abh. Senckenberg. Ges., xxii. (1896) 321 pp., 63 pls.r 4 maps and 5 figs. 1897 i 114 SUMMARY OF CURRENT RESEARCHES RELATING TO sand ; and (3) tlie region of horny corals and sponges. About 40 new species of Antliozoa ( Alcyonium , Sarcophylon , &c.) were found. Note- worthy were a number of Gastropods parasitic on Echinoderms. The second region yielded a little lancelet. A small Gephyrean was found as a commensal of a small single coral. The author has a good deal to say in regard to the wondrous colours of the “ sea-gardens ” — protective colours, warning colours, mimetic colours, sexual colours — originating in the course of metabolism, influ- enced by environment, and fixed by selection. The theory of the polar origin of faunas is rejected on various grounds ; in fact, too simple generalisations are fallacious ; distribution is a function of very numerous factors. A discussion of the Malayan distribution, e.g. of such features as Wallace’s line, is full of interesting material. But a summary of such a large work is obviously out of the question here. We must be content to congratulate the author on his magnificent and important work. Tunicata. Development of Anterior Portion of Salpa.* — Signor F. Todaro divides the development of Salpa ( S . africana maxima) into two periods. The first period embraces the formation of the gut, the endoderm of which, completely closed, is surrounded by ectoderm. Between these two membranes, separated by mesenchyme, there arise the peribranchial sac, the cerebral vesicle, the pericardial sac, and in the chain-embryo some traces of reproductive organs. The second period is initiated by the formation of the primitive buccal cavity, and includes the differen- tiation of the organs mentioned above into their adult state. The primitive buccal cavity or paleeostome shows palingenetic sim- plicity in its origin. In its first stage it is an open ectodermic invagina- tion ; in a second stage the external aperture is shut, and the palasostome is a closed sac ; thereafter, when the brain shows three vesicles, a communication between buccal sac and gut is effected ; an opening is formed between the anterior cerebral vesicle and a dorsal diverticulum of the paleeostome — the anterior neurenteric canal of Kupffer, the “ palaeoneural canal ” of Todaro ; much later, a secondary ectodermic invagination forms the stomedseum, or neostome, or definitive mouth. The communication between cerebral cavity and palseostome is subsequently lost, the diverticulum of the latter becoming a ciliated pit, the palseoneural canal becoming a blind infundibular canal. From the infundibular vesicle are formed two hypophysial vesicles, while two ectodermic diverticula give rise to the tubular part of the hypophysial gland. Thus ike paired hypophysial or subneural gland of Salpa has a double origin — from the cerebral infundibulum and from the ectoderm of the palaeostome. The last thing to be formed from the paheostome is the peripharyngeal groove. Cerebral ganglia, olfactory ganglia, eyes, and peripheral nerves are derived from a mass of indifferent cells in the cerebral region. The paired olfactory ganglia are first mapped out and separated from the cerebral rudiment ; the originally small cells become large, and two nerves are given off to the ciliated pit. * At ti R. Accad. Lincei Bend., vi. (1897) pp. 51-61 (1 fig.) ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 115 In the remaining mass continued cell-multiplication goes on. A stratum of white matter appears dividing an upper part — the optic lamina — from a larger lower part — the cerebral ganglion. From the optic lamina there differentiates in the solitary form the horseshoe- shaped unpaired eye ; in the aggregate form there arise the optic spheres which give origin to the rudimentary posterior eye and the two com- pletely developed anterior eyes. Grey and white matter are differentiated in the brain. From a zone of large nerve-cells motor nerves arise ; very small cells, present in great abundance, are probably sensory. From the anterior surface of the ganglion there arise two mixed nerves with two roots — an inferior in the large motor cells, a superior in the small sensory cells. The nerves supply the buccal muscles and the sensitive epithelium of the buccal cavity. Tunicata of Norwegian North- Atlantic Expedition.* — The hand- somely illustrated volume which deals with these forms consists of five parts. The Synascidiae are discussed by Mr. H. Hvitfeldt-Kaas, the Ascidise Simplices and Composite by K. Bonniere, who deals also with the budding of Distaplia magnilarva and Pyrosoma elegans. Mr. J. Kiser gives a list of Norwegian simple Ascidians ; while Mr. J. Hjort has an essay entitled “ Germ-layer Studies based upon the Development of Ascidians.” Of the 24 species of Synascidians, a third are new to science, but the slight amount of literature on the subject has made the determination of the forms a matter of some difficulty. Eleven species of Simple and ten of Compound Ascidians were col- lected by the Expedition, and most were represented by a single speci- men, not always in a good state of preservation. The development of the buds of Pyrosoma was found to proceed according to the same laws as those which govern gemmation in the Synascidiaa ; the outer vesicle has no share in the development of the bud, the most important organs being formed from the inner vesicle. The peribranchial cavities and the nervous system are not formed, as in the Synascidim, by a simple evagina- tion of the wall of the inner vesicle, but this is due to the great thickness of the layer of cells. The difference between the present results and those of Seeliger may be well explained by the difficulties of the inves- tigation of Pyrosoma. Our space does not permit us to give a full account of Mr. Hjort’s memoir ; we must content ourselves with saying that, after describing the embryonic development of Ascidians, the bud-rudiment in the various groups, and the formation of the organs in the bud, he compares larval and bud development and discusses gemmation in Ascidians and the germ-layer theory, as well as Ascidian development and the biogenetic fundamental law. Tunicata of the ‘ Caudan ’ Expedition. — The few Tunicata col- lected by Prof. Koehler in the Bay of Biscay are divided between Prof. L. Roule, who takes the simple forms,! and M. M. Caullery,* who deals * DenNorske Nordhavs-Expedition, xxiii. (1S96). I. 27 pp. and 2 pis. ; II. 16 pp. and 2 pis. ; III. 23 pp. and 1 pi. ; IY. 15 pp. and 3 pis. ; Y. 72 pp. and 4 pis. t Resultats Scient. de la Campagne du ‘ Caudan,’ fasc. ii. (1896) pp. 355-8. x Op. cit., pp. 359 and 60. 116 SUMMARY OF CURRENT RESEARCHES RELATING TO with the only Compound Ascidian that appears to have been col- lected. The simple forms belong either to Ascidia or Ascidiella, but the sole species of the latter, A. scabra , has not till now been known to be more than littoral in its habitat. Ascidia guttulata sp. n. is very near to A. mentula , and appears to represent it at great depths. M. Caullery has some instructive notes on a phase in the reconstitu- tion of a colony of Biazona violacea. INVERTEBRATA. Brook’s Collection from the West Coast of Scotland.* * * §— Mr. T. Scott has a report on a collection of marine dredgings and other natural history materials made on the West Coast of Scotland by the late George Brook. About 344 species of Invertebrates, chiefly Mollusca, Crustacea, Echinoderma, and Eoraminifera, have been determined ; nearly all the Amphipods are said to be of interest. Echinus norvegicus was taken in the deep water of Loch Buy, Mull. Fauna of the Kaiser Wilhelm Canal. t — Prof. K. Brandt has studied the rapid peopling of this canal (from the lower Elbe to the Bay of Kiel) with marine animals. The sea-water was admitted in May 1895, and already five animals are found throughout the whole canal (100 kilo- metres), viz. Balanus improvisus, Gammarus locusta, Mysis vulgaris , Polydora ciliata , and Membranipora pilosa. Others, such as the edible mussel, the cockle, My a arenaria , were found only in the eastern part. Others, namely, species of Enchytrseus , Carchesium , and Vorticella, were found only in the western part. Two freshwater forms — a Perlid and a beetle larva — were found near the opening of a stream into the canal* but otherwise freshwater forms were absent, Mollusca. a. Cephalopoda. Gigantic Cephalopod.J — Prof. A. E. Verrill has received informa- tion of an immense “Octopus” having been cast ashore not far from St. Augustine, Ela., XJ.S.A. The body measured 18 ft. by 10. Prof. Verrill thinks it was a Squid, which probably weighed 4 to 5 tons. In a further note § Prof. Verrill reports that he has seen photographs of this huge creature, which show that it was probably a true Octopus of colossal size. The revised weight is given as at least 6 or 7 tons, and “this is doubtless less than half of its total mass when living.” The species appears to be undescribed, and it is proposed to call it 0. giganteus. It is probably one of the kinds on which the sperm-whale regularly feeds. Embryology of Nautilus. ||— Dr. A. Willey has been successful in observing the first stages of the ova of Nautilus macromphalus at Lifu. The eggs are laid singly and at night in concealed situations ; they are * Proc. Roy. Phys. Soc. Edinb., xiii. (189G) pp. 166-93 (1 pi.). t Zool. Jabrb. (Abtli. Syst.), ix. (1896) pp. 387-408 (2 maps). I See Ann. and Mag. Nat. Hist., xix. (1897) p. 240. § Amer. Journ. Sci., iii. (1897) pp. 162-3. || Proc. Roy. Soc. Lond., lx. (1897) pp. 467-71 (6 figs.); and Nature, lv. (1897) p. 402 and 3 (6 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 117 enclosed in two capsules ’of a milk-wliite colour and cartilaginous con sistency. The egg, with its outer covering, may be as much as 45 mm. long ; the yolk is of a rich-brown colour and very fluid ; the large quan- tity present points to the occurrence of a long period of incubation. The breeding of this creature, as of so many other forms, appears to be subject to a definite law of periodicity. y. Gastropoda. Yolk-Lobe and Centrosome of Fulgur.* * * § — Prof. J. Playfair M‘Mur- rich described some years ago (1886) the occurrence of a single large yolk-nucleus in Fulgur carica, but he now finds that this was a mistake. What he took to be a large polar globule is simply a small yolk-lobe comparable to that which occurs in many Gastropods. There are two or three true polar bodies. He describes the centrosomes and “ astrocoels ” observed at the stage preparatory to the appearance of four cells, and notes that the rapid increase in size of centrosomes and astrocoels begins just when the formation of the equatorial plate is completed, i.e. just when the movement of the chromatin towards the equator of the spindle ceases. The Genus Doriopsilla.'j' — Hr. B. Bergh established this genus in 1880, on the strength of two specimens from Lesina, in Dalmatia, but he has not until recently been able to procure any others. Two more have been found by Dr. A. Nobre (Foz do Douro-Porto), and their dis- tinctiveness from Doriojpsis is confirmed. They are stiff and almost brittle animals, and the back has a granular appearance, thus differing from the soft and smooth-backed Doriojpsis. The buccal ganglia, instead of being behind the central system, are shunted forwards towards the end of the suctorial apparatus. A general description is given. 5. Lamellibranchiata. Dreissensia polymorpha.f— Prof. J. Frenzel maintains, on the basis of many observations, that the colonies of Dreissensia can move en bloc , without separation of the individuals being necessary. When winter approaches the colonies move gradually from the shallower regions, and no isolated individuals are to be found. As to the actual movement, Frenzel notes that the young forms have three modes of motion (1) they fix their foot and draw the body after it ; (2) they push their way with their foot behind ; and (3) they clap their valves. The movement of the colony is probably altogether due to the younger members, for the foot eventually degenerates. Perhaps the strangest fact is the apparent unanimity within the colony, whose bond is little more than that of chance association. The author acutely suggests that the dissenting members break themselves off. Anatomy of Sphsermm soleatum.§ — Mr. G. A. Drew has recently sent us a short account of the anatomy of this Cyrenid, which is intended as an introduction to an account of the comparative anatomy of the * Anat. Anzeig., xii. (1896) pp. 534-9 (4 figs.). f Zool. Jahrb. (Abth. Syst.), ix. (1896) pp. 454-8. X Biol. Centralbl., xvii. (1897) pp. 147-52. § Proc. Iowa Acad. Sci., iii. (1895) pp. 173-82 (3 pis.). 118 SUMMARY OF CURRENT RESEARCHES RELATING TO Cyrenidse. The byssal gland is much reduced, the inner gills alone function as brood-pouches ; digestion is thought to be a continuous pro- cess, and it has seemed worth while to put on record that “ the regular three pairs of Lamellibranch ganglia are present.” Bryozoa. Notes on Cyclostoma.* — Mr. S. F. Harmer is able to confirm the normal occurrences of embryonic fission in these forms by an account of Idmonea serpens , the ovicell of which is shown to be a modified zooecium. Dealing next with the lately expressed view of Dr. J. W. Gregory that there are no true genera among Cyclostoma, Mr. Harmer urges that that naturalist has not sufficiently noticed the ovicells, the value of which in classification has been urged by Mr. Waters and himself. Dealing with various recent species the author shows that they may be distinguished by means of their ovicells, and he expresses the opinion that it is possible to draw precise diagnoses of recent Cyclostomatous genera. There is probably a law of growth common to all recent species. Eschara lapidescens van Baster.j* — Mr. R. T. Maitland discusses this calcareous zoarium from the brackish water of Zeeland. It seems — so far as we understand the paper — to be a form of Membranipora ; but the author points out that neither Lamarck, nor Johnston, nor Hincks, nor P. J. van Beneden have taken knowledge of van Baster’s observa- tions (1759). Arthropoda. Tegumentary Innervation in Arthropods.^ — Herr E. Holmgren re- fers to his work (published in Swedish §) on the integument of cater- pillars. The larger nerves show an arborescent branching, the smaller are dichotomous. The fine twigs end partly in bipolar sensory nerve-cells, the unbranched terminal process of which runs out into a hair or passes between two epidermic cells up to the cuticle. In caterpillars there seems to be no trace of a ganglionic grouping of nerve-cells such as is often seen in Crustaceans ; and another difference is that the nerve-cells in caterpillars are much more superficial. Most of the hairs on the body are provided with sensory nerve-cells ; they are at once glandular and sensitive. Sometimes, as Rina Monti has also shown, the nerve-cells in the skin of insects are multipolar, and a plexus arrangement, as in Ctenophora, is sometimes demonstrable. Like Retzius and vom Rath, the author has found only bipolar sensory nerve-cells in the Crustacean skin. Ramified connective and pigment-cells may be seen sending processes into the hairs. Perhaps the multipolar nerve-cells described in Astacus by Bethe are really connective. a. Insecta. Larvae of British Butterflies and Moths.|| — Mr. G. T. Porritt con- tinues the editing of the late William Buckle’s work ; this, tho seventh, * Proc. Cambridge Phil. Soc., ix. (1897) pp. 208-14. t Tijdschr. Nederland. Dierk. Ver., v. (1896) pp. 10-14. X Anat. Anzeig., xii. (1896) pp. 449-57 (7 figs.). § K. Svensk. Vetenskaps-Akad. ITandl., xxvii. (1895) No. 4. || London, printed for the Ray Society, 1897, xv. and 176 pp., pis. cvi.-cxxvii. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 119 volume deals witli part of the Geometry. It is too late in the day to praise the plates, the excellence of which is known to every entomologist. The volume concludes with a list of parasites bred from larvae or pupae included in this part ; of these there are more than one hundred. Larvae of the Higher Bombyces.* * * § — Mr. HarrisomG. Dyar describes the larval setae of the Bombycides (this older name must be used instead of Noctuina or Agrotides), and applies his results to taxonomic purposes. He gives a genealogical tree of the family, and appends a synopsis of the superfamilies of Lepidoptera. Mandibular Glands of Cossus ligniperda.f — M. Maurice Henseval describes the mandibular glands enormously developed in the larvae of Cossus ligniperda. They open at the internal angle of the mandible ; they include a secretory portion, a reservoir, and a duct ; and they probably correspond to the coxal glands of Peripatus. The secreting part is lined by a cuticle like that in Gilson’s glands in the Trichoptera. Like these, they secrete a substance oily in appearance, containing an aromatic nucleus, and composed of carbon, hydrogen, and sulphur in the propor- tions C22H35S. The substance does not attack wood, nor is it toxic ; but it is perhaps protective against certain fungi, and against insects with parasitic larvae. In another paper J the author discusses more fully the physical and chemical characters of the secretion. Structure of Nuclei in Spinning Glands of Caterpillars.§ — Dr. F. Meves finds that the nuclei of these glands are extraordinarily rich in chromatin. This is in the form of small, almost equal-sized granules (Korschelt’s microsomes), and exceptionally in clumps. But the nuclei also contain an unusual number of nucleoli (Korschelt’s macrosomes), often several hundreds. These are frequently irregular in form, an- gular, spindle-shaped or rod-like, and may contain a large vacuole or several small vacuoles. Abdominal Appendages.|| — Herr R. Heymons shows that there is very little evidence — either anatomical or embryological — in support of the opinion, held by Verhoeff for example, that gonapophyses are derivable from locomotor appendages. The styles seem to be skin processes replacing appendages ; the cerci and the antennae are on a higher level retaining vestiges of their appendicular nature. But what Heymons makes clear is that no strict line can be drawn between hypo- dermic processes and appendages. The facts of nature will rarely admit of rigid distinctions. Cynips Calicis.^f — Herr M. W. Beijerinck discusses the formation of galls and the alternation of generations in the case of Cynips calicis. He has shown that the Cynips calicis of the Stielleiche ( Quercus pedunculata ] has as its second generation Andricus cerri of the Zerreiche ( Quercus cerris'). He describes what he has observed of this heterogenesis and the development of the galls. A digression is then made to discuss the * Proc. Boston Soc. Nat. Hist., xxvii. (1896) pp. 127-47. t La Cellule, xii. (1897) pp. 19-29 (1 pi.). X Tom. cit., pp. 169-83. § Arch. f. Mikr. Anat., xlviii. (1897) pp. 573-9 (1 pi.). || Biol. Centralbl., xvi. (1896) pp. 854-64. Verh. K. Akad. Wetenschap. Amsterdam, v. (1896) pp. 1-43 (3 pis.). 120 SUMMARY OF CURRENT RESEARCHES RELATING TO circulans-gall due to Andricus circulans in whose life-history hetero- genesis is also probable, though not exactly demonstrated. Of galls in general the author notes that the higher the final differen- tiation, the younger must be the initial cells of the vegetable tissue which are affected by the animal excreta. All Oynipid-galls arise from a group of vegetable cells, 250-2000 in the case of Cynips calicis. Any theory of the formation of the gall must keep in view the diffusion of the irritant substance through a cell-complex. The facts seem to Beijerinck to show that variation is a function of multicellular relations in the case of most galls. It seems to us that most biologists would regard galls as phenomena of modification rather than of variation, but the author is no doubt right in emphasising their importance in connection with the general problems of organic growth and organic change. Coloration of Scales in Beetles.* * * § — Sig. A. Garbasso has been in- vestigating the physical coloration of certain insects, but has, he notes, been in part forestalled by Walter’s book on Schillerfarben. In this paper he confines himself to a description of the structure of the scales in the Curculionid Entimus imperialis, and to showing that its brilliant colours are due to phenomena of interference. Life-History of Dendroetonus micans.j — MM. A. Menegaux and J. Cochon call attention to the biology of this largest of xylophagous insects, which was unknown fifty years ago, and was long thought to be innocuous. The great danger connected with it is that it never attacks dead trees or trunks, but always healthy trees ; a tree weakened by it may be subsequently attacked by other xylophagous forms, such as Bostrichus. Abdomen of Scolytidse.i — Dr. C. Verlioeff has studied the abdomen of Scolytidee, with special reference to the work of Prof. C. Lindemann (1875) on the same subject, and with general reference to the morphology of the insect-abdomen. As the tersest possible summary of his results fills three pages, we cannot do more than refer to the general tenor of Verhoeff’s paper. Bees Intoxicated with Honey.§ — Mr. J. L. Williams describes the remarkable effect produced on humble-bees by the honey of certain flowers with dense capitulate inflorescence belonging to the Composite and Dipsacaceae : — Centaur ea nigra , C. scabiosa, Car duus lanceolatus , C. nutans, and Scabiosa succisa. The species chiefly observed were neuters of Bombus lapidarius. After extracting the honey, the insect suddenly turned on its side and moved the second pair of legs convulsively in the air ; some even turned on their backs and rolled on the flowers. After a time a few tried to fly away, but their wings seemed powerless to raise them into the air, and they fell on the ground instead. As a rule, when driven away, they were eager to return. During this proceeding the bees invariably became covered with pollen, and the author suggests that the habit may be useful to the flower in promoting cross-pollination. * Mem. R. Accad. Sci. Torino, xlvi. (1896) pp. 179-86 (1 pi.). 1 1 Comptes Rendus, exxiv. (1897) pp. 206-9. X Arch. Naturges., lxii. (1896) pp. 109-44 (2 pis.). § Journ. Bot., xxxv. (1897) pp. 8-11. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 121 Italian Coccidse of Fruit-Trees.* * * § — Prof. A. Berlese deserves to be congratulated on bis memoirs dealing with Coccid insects living on fruit-trees in Italy. These insects are interesting in their structure and life-history; they are not less interesting to the practical man whose orchards they infest. Both aspects receive due consideration from Prof. Berlese, who furnishes on the one hand a most detailed morpho- logical account, and on the other hand what we may call a system of practical lore. As will be seen from our reference the abundance of illustrations is a feature of these memoirs. The first deals with the genus Dactylopius, with two species, D. citri Bisso and D. longispinus Targ. Tozz. The second deals with the genus Lecanium, with two species, L. hesperidum Linne, and L. olese Bernard. The third deals with six species of Diaspitidae — Mytilaspis fulva Targ. Tozz., M. pomorum Bouche, Parlcitoria Zizyphi Lucas, Aspidiotus dimonii Signorot, A. Ficus Kiley, and Aonidiella Aurantii Mask. Buccal Glands of Larval Trichoptera.-j* — M. Maurice Henseval finds that the larvae of Trichoptera may exhibit at the base of their masticu- latory organs one or two pairs of glands with intracellular canals. They were absent in the Phryganid larvae examined, but these have “ Gilson’s glands ” much developed. The organs in question probably represent the coxal glands of the anterior metameres. How Flowers attract Insects.^ — Pursuing his researches on this subject, Prof. F. Plateau has come to a different conclusion from that of Darwin, who held that it is chiefly the bright colour of the corolla that attracts insects to flowers for the purpose of pollination. His experiments were made chiefly on Dahlia variabilis (single), Lobelia Erinus , (Eno - thera biennis , Delphinium Ajacis , Ipomsea purpurea, Centaurea Cyanus, and Digitalis purpurea. In the case of the Dahlia and other Composite the removal of the conspicuous ray-flowers had very little effect in diminishing the number of insects which visited them ; these cannot therefore play the part of signals or banners attributed to them by Darwin and others. Similar results were obtained by removing the conspicuous part of the corolla in the other flowers which were subjected to observation. Covering up of the flower by leaves also had but little hindering effect on the visits of insects. The author concludes that insects are attracted to flowers chiefly by some other sense than that of sight, probably by that of smell. Prof. Plateau further states as the result of experiments on these points, that insects visit indifferently flowers of different colours belong- ing to the same species ; § that they light without hesitation on flowers habitually neglected when these are artificially supplied with honey ; and that they at once cease their visits to the customary flow'ers when the nectary has been removed from them. * Part I. ex Piivista Patologia Vegetale, ii. (1893) 106 pp., 3 pis. and 45 figs. ; Part II. ex op. cit., iii. (1894) 201 pp., 12 pis. ; Part III. ex op. cit., iv. and v. (1896) 477 pp., 12 pis. and 200 figs. f La Cellule, xii. (1897) pp. 7-15 (1 pi.). J Bull. Acad. R. Sci. Belgique, xxx. (1895) pp. 466-S8; xxxii. (1896) pp. 505-34 (1 pi.) ; xxxiii. (1897) pp. 17-41. Cf. this Journal, 1896, p. 305. § Similar results were obtained by Mr. A. W. Bennett (Journ. Linn. Soc. ; Zool., xvii. (1883) p. 175). 122 SUMMARY OF CURRENT RESEARCHES RELATING TO Mallophaga from Land-Birds.* — Prof. Y. L. Kellogg not only de- scribes some new Mallopbaga from American land-birds, but gives an account of the mouth-parts of these ectoparasites. The parts in question are found to be distinctly fitted for biting ; there is nothing which lends any probability to the old theory that the Mallophaga suck their food. The author has, indeed, seen these parasites biting off and eating bits of feathers, and the crop always contains tiny bits of feathers. The Mallophaga seem to certainly belong to the group Platyptera, and it is, therefore, with other members of that group that the author compares their mouth-parts. There is a peculiar and interesting simi- larity of mouth-structures between the Mallophaga and the Psocidee ; the latter, it is important to note, have somewhat similar feeding habits to the former, for they live on dry dead organic matter, such as wood and paper, dried insects, dried bird and mammal skins. The author concludes with a list of hosts and parasites. S. Araclinida. Hydraehnida of Germany.^ — Dr. R. Piersig has published the first part of a beautifully illustrated monograph on the Hydraehnida of Germany. He gives a history of previous researches dealing with this group. The family Hydrachnidae is divided into five sub-families : — Hygrobatinse, Hydryphantinre, Eyla'inae, Hydrachninre, and Limno- charinae. The Hydrachnidse live wholly in water, almost all in fresh water. They are marked by the compressed body, unsegmented trunk, 5-jointed palps, and 6-jointed feet usually ending in a double claw. The mouth-parts form a suctorial proboscis ; the mandibles are distinctly 2-jointed except in Hydrachninae. There are four anterior lateral eyes, usually fused into a double eye on each side ; and there may also be an unpaired median eye-spot. There are two tracheal stigmata above the mouth-opening, leading into air-reservoirs, and thence (except in Atax) into tracheae. In addition a skin respiration is probably general. There is no heart nor vascular system. The alimentary system has marked resemblances with that of Trombidia. A ganglionic mass pierced by the gullet represents brain and nerve-cord. The sexes are separate and the females oviparous. The animals live on Crustaceans, dipterous larvae, and Infusorians. They are very hardy; thus many can resist considerable salinity. Their distribution seems mainly due to insects. Structure of Gamasidse.J — Sig. F. Neri describes the common Der- manyssus gallinse Redi ; the soft, depressed, oval body ; the membranous, transparent, slightly chitinised integument; the variable coloration, partly depending on the contents of the ?gut ; the rapid movements of the four pairs of limbs ; the strongly developed striped muscles ; the rostrum, buccal cavity, pharynx, oesophagus, stomach, stomachic diverti- cula, and intestine ; the tracheal respiration ; the two dorsal tubes which seem to be excretory ; the sexual differences ; the copulation ; the * Proc. Calif. Acad. Sci., vi. (1896) pp. 431-548 (14 pis.) ; also separately Leland Stanford jr. University. t Bibliotheca Zool. (Leuckart and Chun), Heft 22, pp. 1-80 (8 pis.), Stuttgart, 1897. X Atti Soc. Tosc. Sci. Nat., x. (1896) pp. 126-38. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 123 colourless elliptical ova ; tlie larvm and the nymphs. A detailed account with figures is forthcoming. Pseudo-Larval Copulation of some Sarcoptidse.* * * § — M. S. Jourdan has made a study of three forms of plumicolous Sarcoptids, often found on the domestic pigeon. In these forms the male copulates with an octopod larva, which has no sexual apparatus ; this paradoxical arrange- ment cannot he understood till it is seen that beneath the skin of the larva a perfect female is being formed, and it is into this that the fer- tilising fluid passes ; hence the suggested term “ pseudo-larval.” Halacarina of the ‘ Caudan ’ Expedition^ — Dr. E. Trouessart has a full and interesting report on the marine A carina collected by Prof. Koehler in the Bay of Biscay ; they are the first of their kind known from great depths, and these latter extended from 180 to 1410 metres. They were chiefly found attached to Amphihelia prolifera and Soleno - smilia varicibilis ; when these corals fail the halacarine fauna becomes excessively poor. As a fact, examples were dredged at five stations only, and representatives of new species were out of all proportion more numerous than those of old ; by far the most abundant was Halacarus abyssorum sp. n. ; there is a single representative of a new genus, Atelopsalis tricuspis sp. n. The halacarine fauna of great depths is remarkable for the complete absence of phytophagous types, the scarcity of predacious or carnivorous forms, the frequency of types with a feeble rostrum and styliform palps, the thinning of the chitinous integument, and the variations in the development of the eyes. Pycnogonida of the ‘Caudan’ Expedition.^ — M. M. Caullery re- ports on the three Pycnogonids collected by Prof. Koehler in the Bay of Biscay. One of these, Paranymphon spinosum , is a new genus and species, but it is to be observed that the sole distinguishing generic character given is the presence of six joints to the palp instead of five, as in Nymphon. g. Crustacea. Functions of certain Diagnostic Characters of Decapod Crus- tacea^— Mr. W. Garstang discusses the value of certain characters used by systematists to distinguish species and genera. For example, the frontal area of Crabs is frequently either 3- or 5-toothed, that is, either 2- or 4-notched. This is an arrangement by which the antennce and antennules, which are organs of great importance, are specially protected against injury. In sand-burrowing species the denticulated margins have the function of sieves. It is not, says the author, generally known that a crab’s chelipeds are in many cases important agents in the process of respiration ; this is explained and illustrated. It appears, to conclude, that many of the specific and generic charac- teristics of Crustacea, which have been hitherto regarded as features of trivial significance, are really of primary importance to their possessors. * Comptes Rendus, cxxiv. (1897) pp. 209 and 10. f Resultats Scient. de la Campagne du ‘Caudan,* fasc. ii. (1896) pp. 325-53 (3 pis.). + Tom. cit., pp. 361-4 (1 pi.). § Rep. Brit. Ass., 1896, 2 pp. (sep. copy). 124 SUMMARY OF CURRENT RESEARCHES RELATING TO Crustacea of the ‘ Caudan ’ Expedition. — M. J. Bonnier * * * § gives an account of the Hedriophthalmia collected by Prof. Koehler in his deep- sea dredgings in the Bay of Biscay. Of the fifty-two species collected many are new, but we notice that a number of them are based on single specimens, and many of the exanqfies are said to be considerably injured.- Specimens were taken from depths varying from 200 to 1700 metres. There are three new genera of Cumacea, two of Isopoda, and two of Amphipoda. In conclusion the author describes a new Copepod of the family Choniostomatidse, which was taken from the branchial apparatus of a Cumacean ; this is, it would seem, the first time that a member of this family has been observed to lead a parasitic life. The Schizopoda and Decapoda j* found during the expedition were entrusted to M. M. Caullery, who has distinguished forty-eight species, five of which are new and representative of two new genera and one subgenus. A number of the already described forms have not till now been known to inhabit the Bay of Biscay. The Copepoda J generally fell to the care of M. E. Canu, who reports on a small but interesting collection, which is attractive as leading to the hope that a large number of interesting additions will be made to the “ French Oceanic Fauna,” when a more complete and methodical study is made of the pelagic life of the French shores. Neoscolecithrix is a new genus formed for N. Koehleri sp. n. Embryonic Nervous System of Crustacea.§ — M. N. de Zograf has made a fresh investigation of this system in the Nauplius of fresh-water Oopepods by the aid of the method of Ramon y Cajal. He has found by it, under the chitinous covering layer, special cells arranged in the same way and in the same places as he found by the aid of methylen-blue. These cells are continued into long nervous filaments, which are con- nected with one another by very thick branches, and which terminate in the sub- oesophageal ganglion. In one exceedingly successful preparation the author can demonstrate two rows of subcuticular cells, connected with one another by the branchings of their filaments. Entornostraca of Lake Mezzola.|| — Dr. N. Rizzardi gives a list of these in an appendix to Prof. P. Pero’s recent monograph on the lake in question. There are eight pelagic species, including Linceus sjphsericus and Cypris ovum, said to be rare in Italy. The genus DapJinia seemed to be unrepresented. Revision of Cladocera.^ — M. J. Richard has undertaken'and completed a work for which he will receive the thanks of microscopists. Dealing, as it does, freely with details, we cannot do more than call the attention of our readers to it. The extent of the author’s work may be somewhat estimated by the fact that he cites no less than 587 titles in his biblio- graphy, which is brought down to 1896. * Resultats Scient. de la Campagne du ‘ Caudan,’ fasc. iii. (1896) pp. 527-689 <13 pis ). f Op. cit., ii. pp. 365-419 (5 pis.). X Op. cit., ii. pp. 421-37. § Comptes Rendus, cxxiv. (1897) pp. 201-3. II Boll. Soc. Rom. Stud. Zool., v. (1896) pp. 126-9. H Ann. Sci. Nat., ii. (1896) pp. 187-363 (6 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 125 Annulata. Marine Annulata of the ‘ Caudan ’ Expedition.* * * § — Prof. L. Roule reports that fifty species were collected by Prof. Koehler in the Bay of Biscay, but nearly a third of them cannot, for various reasons, be deter- mined ; this is especially the case with the tubicolar forms. There are only five new species, and three new varieties ; the facts of bathymetric distribution recall what has been observed in other groups of animals. Polychaeta of the Netherlands.-]-— Dr. R. Horst gives a list of forty- one species of Chaetopoda (including Sagitta bipunctatd) known to belong to the Netherlands. It is interesting to compare it with the British list. North American Oligochseta.f — Mr. F. Smith has notes on various earthworms collected at Havana, 111., by the University of Illinois Biological Station. Additional information to that of Ude, whose speci- mens were poorly preserved, is given concerning Geodrilus singularis ; corrections are made in the account of Diplocardia riparia , first described by the author. Thinodrilus is a new genus formed for T. incrustans, a Lumbriculid from Quiver Lake. il lesopodrilus asymmetricus is another new Lumbriculid from the same lake. Oligochaeta of South America.§ — Mr. F. E. Beddard has a report on the Naidae, Tubificidse, and Terricolae collected by the Hamburg Expe- dition to the Strait of Magellan. The material was in excellent condition for microscopic examination, and the author has been able to describe a number of new forms. Hesperodrilus is a new genus with four new species, and a large number of Acanthodrilus are described ; in all seventeen species of that genus are recorded. Microscolex is also well represented. Lymphocytes of Earthworms.lt — Dr. D. Rosa distinguishes and describes four different kinds of lymphocytes in Oligochceta: — (1) In Allolobophora rosea ( = A. mucosa ) there are non-amoeboid mucous elements; (2) in A. foetida , A. chlorotica, & c., there are non-amoeboid oily elements ( eleociti ) ; (3) a third type is distinguished as vacuolar ; and (4) thero are the ordinary amoeboid lymphocytes. Unpaired Gland of Haementaria.^f — Herr H. Bolsius describes a peculiar gland which lies above the proboscis of Hsementaria officinalis , a leech which, though without teeth or tooth-plates, seems to be used for medicinal purposes in Mexico. The posterior part of the gland is delicate and coiled, the middle part is large and straight, the anterior part is an efferent canal which bifurcates behind the cerebral ganglia, re- unites its branches, and ends on the upper lip. It is peculiar in being unpaired. Its lumen seems to be intra-cellular. Its cells are remark- * Resultats Scient. de la Campague du ‘ Caudan,’ fasc. iii. (1896) pp. 439-71 (7 pis.). t Tijdschr. Nederland. Dierk. Yer., v. (189G) pp. 15-28. j Bull. Illinois State Lab. Nat. Hist., iv. (1895 and 6) pp. 287-97, 396-413 (4 pis.). § Hamburg, L. Frederichsen & Co., 1896, 8vo (sep. copy), 62 pp. and 1 pi. || Mem. R. Accad. Sci. Torino, xlvi. (1896) pp. 149-78 (1 pi.). 1 La Cellule, xii. (1897) pp. 101-12 (1 pi.). 126 SUMMARY OF CURRENT RESEARCHES RELATING TO able in showing a preponderance of the circular (as opposed to radial and longitudinal) components of the cytoplasmic trabecular framework. “Urns” of Sipunculus.* — MM. J. Kunstler and A. Gruvel have traced the history of these peculiar bodies found in the perivisceral fluid of Sipunculus nudns. Some have regarded them as parasitic Infusorians, but that they are in reality free epithelial cells has been proved by Brandt, Bay Lankester, Cuenot, and others. The normal “ urn ” most frequently seen is but one stage in a series. It becomes a disc, and gives rise to amoeboid cells, which gradually grow into urns. The authors also describe the “ enigmatic vesicles ” found along with the urns, but, as they confess, it is very difficult to follow the complex transformations without figures, for which we must wait. Rotatoria. Locomotor Apparatus of Rotifers.j — M. N. de Zograf finds in all the Rotifers which he has examined that the cells which carry the vibratile cilia are connected by nerve-filaments with the nerve-ganglion of these animals ; Floscularia and Stephanoceros are said to be excep- tionally interesting, as the cells in question show very markedly the characters of distinct nervous cells. Nematohelminthes. The Genus Ascaris4 — Prof. M. Stossich has published a systematic monograph of the genus Ascaris. The list of species amounts to 218, and the list of hosts to 432. This compact account should prove useful to workers in this difficult field. Life-History of Ascaris lumbricoides.§ — Dr. G. Brandes notes that almost all the text-books are misty in regard to the mode in which man is infected by this common parasite, while others cite von Linstow’s (quite theoretical) opinion that Julus guttulalus is the intermediate host. But in 1881 Prof. Grassi showed by experiment on himself that direct infection by eggs was effective. In 1888, Lutz showed the same, if the external shell is preserved. With this Davaine (1877) also agrees. Further experiments by Lutz and by Epstein (1892) were quite conclusive ; and the results got by Epstein also show that mature females may develop in 10-12 weeks. To this we may add that Prof. Stossich, in his monograph on Ascaris, credits von Linstow with suggesting that Polydesmus complanatus (as well as Julus guttulalus') as an intermediate host, while he mentions Calandruccio (1889 ?) as having experimentally proved the effectiveness of direct infection. Ascaris megalocephala as Cause of Death. || — Herr Graefe describes the case of a seven-year-old horse which suffered from progressive ema- ciation and cramps. A post-mortem examination revealed peritonitis, caused by two maw-worms (Asc. megalocephala) which had perforated the wall of the intestine. In the small intestine, the mucosa of which * Comptes Rendus, cxxiv. (1897) pp. 309-12. f Tom. cit., p. 203. X Boll. Soc. Adriat. Sci. Nat. Trieste, xvii. (1896) pp. 9-120. § Biol. Centralbl., xvi. (1896) pp. 839-41. || Deutsche Tierarztl. Wochenschr., 1896, pp. 29-30. See Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) p. 932. ZOOLOGY AND BOTANY* MICROSCOPY, ETC. 127 was mucli inflamed, were found a couple of pailfuls of Ascarides. There were none in the large gut. In the stomach was about another pailful of worms which had probably migrated there after death. Simondsia paradoxa in the Stomach of Wild Soars.* — Sigg. V. Colucci and L. Arnone found in the stomachs of three wild boars nume- rous Simondsia paradoxa. The males were not free in the stomach, for the middle part of the body lay beneath the mucosa from which the ends projected. The authors believe that Cobbold confused the male of Spiroptera strongilina with that of Simondsia paradoxa. The latter has not two spines and two lobes on the tail. The posterior end of the female is mulberry-shaped. The histology of the worms is described at some length. In the streams of the woods inhabited by the boars the authors found some nematode larvae 0 • 65 mm. long and 0 • 02-0 • 025 mm. broad, devoid of sexual organs but possessed of a digestive system very similar to that of Simondsia paradoxa. The posterior end is thick and globose. The authors believe that they had to deal with a female of Simondsia paradoxa . Helminthological Notes, f — Dr. M. Stossich notes seven worm- parasites from a large specimen of Orthagoriscus mola. The list includes AnchistrocepJialus microceplialus Rudolphi, Dibothriorhynchus gracilis Wagner, and Echinostoma lydise Stossich. In another paper f he records the occurrence of about eighty forms, e.g. Ichthyonema jiliformis Stossich in the ovary of Pagellus erythrinus and Trachinus draco , Strongylus ersilise Stossich in a python, Distoma vallei Stossich in Falco subbuteo, and so on. Platyhelminthes. Excretory Organs and Blood-Vascular System of Tetrastemma graecense.§ — Dr. L. Bokmig has a preliminary account of this freshwater Nemertine which he has found in abundance at the Botanic Garden at Graz. On either side of the body there is a system of clear, arborescent, and interconnected canals which extends through the whole length of the worm. At the anterior end of the body there is a single larger canal which ends in a fine closely-meshed plexus of very small vessels. The excretory organs may be considered under the three heads of terminal canaliculi connected with the terminal organs, connecting canals, and primary canals ; these are all briefly described. There is not the close connection between the nephridia and the blood-vessels in T. gracense , which Burger has described for the marine Metanemertines. The blood-vascular system consists of two lateral and one dorsal vessel ; anteriorly the latter opens into the right lateral vessel, and posteriorly into the anal commissure of the two lateral vessels. Notes on Trematoda.|| — Herr P. Muhling describes Distomum flexu- osum Bud. from the intestine of the mole ; D. longicauda Bud. from the * Mem. B. Accad. d. Sci. dell’ 1st. di Bologna, serie v. tomo vi. (1 pi.). See Centralbl. f. Bakteriol. u. Parasitenk., lt0 Abt., xxi. (1897) p. 215. t Boll. Soc. Adriat. Sci. Nat. Trieste, xvii. (1896) pp. 189-91 (1 pi.). + Tom. cit., pp. 121-36 (2 pis.). § Zool. Auzeig., xx. (1897) pp. 33-6. 11 Arch. f. Naturges., lxii. (1896) pp. 213-79 (4 pis.). 128 SUMMARY OF CURRENT RESEARCHES RELATING TO gall-bladder of the grey crow ; D. Mans Eud. from the gullet of the white stork ; D. tenuicolle Eud. from the liver of the grey seal ; D. cirratum Eud. from the intestine of the carrion crow ; D. platyurum sp. n. from the intestine of the long-tailed duck ( Harelda glacialis) ; and Cyatho- cotyle prussica g. et sp. n. from the same. Taenia Botrioplitis in the Intestine of the Fowl.* — Taenia botrioplitis is a tapeworm discovered by Piana, and is, says Herr G. Scagliosi, from 50 to 200 mm. long, has a circlet of hooks and roundish suckers on its head. The neck is unsegmented, and there are sexual organs in each of the proglottides of the segmented body. This specimen of Taenia was found by the author in numerous small nodules in the serosa of a fowl, the head of the worm being buried in the nodule. Microscopical examination of the gut in the neighbourhood' of the Taenia showed necrosis of the intestinal wall, associated with a small-celled infiltration and the presence of giant-cells. In those nodules which contained no worm the necrosed parts had become encapsuled in connective tissue, and hung by a pedicle attached to the outer wall of the intestine. Nervous System of Ligula in its Eelations to the Arrangement of the Musculature.! — Herr M. Liihe has shown that the longitudinal muscles of Taeniae can always be differentiated into an inner, an outer, and a subcuticular layer, and that the two latter have a common origin. Similar relations are found in the Botliriocepliali , though in them the separation of the muscular layers is much less obvious than in the Taeniae. Yet in Ligula the inner layer of muscle is somewhat sharply differen- tiated from the outer. This is owing to the position of a band of longi- tudinal nerves which separate the two layers of muscle. The nerves of this separating layer are connected with one another and with the main lateral nerves by commissures. Owing to this, the nervous system of Ligula is much more complicated and more nearly approaches that of the Trematoda than has been hitherto supposed. The observation is all the more noteworthy, inasmuch as, up to the present, commissures uniting the longitudinal nerves have been found only in a few Cestoda. Ctenoplana.J — Dr. A. Willey has been able to make an interesting and important study of this remarkable genus, which presents affinities both to the Turbellaria and the Ctenophora. The most important generalisation to which the author is led is that the group Bilateralia have had a diphyletic origin, and he exhibits his results in the following table : — f Ctenophora o 'Archiplanoidea. .Cerianthidao . [ Platy helminthes {Anthozoa Coelomata * Virchow’s Arcli. f. Path. Anat., cxliv. pt. iii. See Centralbl. f. Bakteriol. u. Parasitenk., P® Abt., xxi. (1897) pp. 35-6. t Zool. Anzeig., 1896, No. 511. See Centralbl. f. Bakteriol. u. Parasitenk.,, llc Abt., xx. (1896) p. 931. X Quart. Journ. Micr. Sci., xxxix. (1896) pp. 323-42 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 129 One advantage of this view is, the author urges, that theories which at one time “ appeared to be logical necessities, will be quite ruled out of the field of possibilities.” The new group Archiplanoidea is for the reception of the families Ooeloplanidge and Ctenoplanidse. Off New Guinea the author found, at any rate, one new species of Ctenoplana , and as his specimens were active, he was able to see that the ctonophoral plates are the sole organs of locomotion. The circlet of sensory tentacles was found to consist of two distinct and separate halves, and this observation is crucial for deciding upon the homologies of the axes of Ctenoplana with those of other bilateral animals. Cilia do not appear to be as generally distri- buted as Korotneff thought. Dr. Willey was so fortunate as to discover the male genital organs of this creature. The author thinks he has proved that — (1) The tentacle axis of Ctenoplana = the longitudinal axis of Planarians. (2) „ stomachal „ „ = the transverse „ „ (3) „ main axis of Ctenoplana and Ctenophores = the dorsoventral axis of Bilateralia. Ctenoplana would, finally, appear to be an ancestral form, and not a highly modified creeping Ctenophore. Echinoderma. Embryology of Starfish.* — Mr. S. Goto has a preliminary note on the development of Asterias pallida , which he has studied at Newport, R.I. From a careful examination of the axes of the larva the author concludes that the oral side of the adult is the anterior, the aboral the posterior, the inadreporic (interradius) the dorsal, and the side opposite this the ventral, side of the larva. Both definite mouth and anus are new formations. With Mr. Bury the author distinguishes four portions in the body-cavity of the larva. The formation of the water-vascular ring is found to be not a mechanical result of the breaking through of the adult mouth, for this ring exists as such some time before the mouth is formed. In agreement with both Mr. Bury and Mr. M‘Bride, Mr. Goto distinguishes sharply the pore-canal and the stone-canal. There is a stage when the first of these alone is present; the two canals are, probably, distinct phylogenetically, and, in comparing Echinoderms with Enteropneustans it seems right that the pore-canal alone should primarily be taken into consideration. It seems likely that the openings of these canals into the body-cavity persist throughout life in all starfishes. Bury’s t{ dorsal organ ” arises as a tube from the left posterior enterocoel, and, as M‘Bride has taught, it forms the perioesophageal portion of the body-cavity of the adult. The perihaemal spaces (with the exception of the inner ring) as well as the peribranchial spaces are reported to be of true schizoccel origin. Echinocystis and Palseodiscus.-f — Dr. J. W. Gregory has some very interesting observations on these two enigmatical Echinoderms; he * Proc. Amer. Acad. Sci., xxiii. (1896) pp. 833-5. f Quart. Joum. Geol. Soc., liii. (1897) pp. 123-34 (2 figs.). 1897 K 130 SUMMARY OF CURRENT RESEARCHES RELATING TO does good service in redescribing the structure of both these Silurian genera. As to the first, he concludes that it is an Echinid and not a Cystid ; and as to the second, that it also is an Echinid and not an Asterid. The diagnoses of the Cystoidea lately offered by Prof. v. Zittel and Prof. Haeckel are considered, and it is strongly urged that they do not enable us to draw any sharp line of distinction between the Cystoidea and the Echinoidea. The masticatory apparatus of the two genera is described and discussed, and it is shown how they may be found to explain the origin of the same apparatus in gnathostomatous Echinoids. Dr. Gregory joins in the attack on the Lovenian doctrine of the homologies of the “ calycinal plates,” and suggests that the plates so called in Echinoids are homologous with the plates of the valvular pyramid of the Cystoidea. Affinities of Echinothuriidae.* — Dr. J. W. Gregory comes to the conclusion that the apparently primitive features of these Echinoids are secondarily acquired and are not primeval. The recent genera, therefore,, are extremely specialised and not primitive forms. The family should be regarded as belonging to the order Diademoida, and as derived from the Pedinidse. The oldest member of the family appears to be Pelane- chinus, and the flexibility of the tests of the existing Asthenosoma and Phoronosoma is regarded as due to a diminished calcification of the plates. The author describes a new genus Pcdinothuria, and gives reasons for regarding it as a connecting link between the Pedinid® and the Echino- thuriidse ; another new genus — Helikodiadema — has a flexible test, duo apparently to its deep-sea life ; it is a modified form of Pseudodiadema. Holothuriidse of Norway.! — Mr. Hj. Ostergren reports that Stichopus griegi sp. n., S. tremulus, and H. ecalearea are the only Norwegian Holothurians that belong to the true Holothuriidee. The new species is said to be closely allied to S. tremulus , but, though he has only a single specimen on which to found his judgment, the author appears to have satisfied himself that it is specifically distinct. Synallactinae.! — Herr Hj. Ostergren has made a study of some forms thought to be well known, and finds that their anatomy has not been thoroughly investigated. For example, the long known Holothuria intestinalis is shown to be a Mesothuria , of which a fresh diagnosis is given. Similarly Sars’ Stichopus natans is found to belong to the sub- family lately instituted by Professor Ludwig, and it is necessary to make for it a new genus which the author calls Bathyplotes ; Stichopus tizardi of Theel must be put into the same genus, and apparently others also. With regard to the systematic position of the Synallactinee the author does not agree with Prof. Ludwig : the latter, it will be remembered, regarded them as a sub-family of the Holothuriidge, and as forming a link with the Elpidiidae. Herr Ostergren thinks that their points of resemblance to the Elpidiidas are so great that they ought to be placed in that order ; the two families just named may, with the Pelago- * Quart. Journ. Geol. Soc., liii. (1897) pp. 112-22 (3 figs.), f Bergens Mus. Aarbog, 1896, No. 12, 10 pp. and 1 pi. j- Festskrift for Lilljeborg, Upsala, 1896, pp. 347-60 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 131 thuriidse, form a group for which the old name of Aspidochirotae will be appropriate. Ccelentera. Stinging-Cells.* — Dr. N. Iwanzoff has investigated the stinging- cells of a large number of Coelentera. All are modified epithelial cells (cnidoblasts), and each encloses a single nematocyst. The nematocyst, or capsule, may be round, oval, or cylindrical in form ; the thread is a tubular invagination of the capsule-wall. Only in Anthozoa are there threads which are ruptured out instead of being evaginated. There are always two kinds of stinging-cells in an animal, and in most Siphono- phora there are four or five kinds. The capsule-wall has two layers — the inner thicker, the outer con- tinuous with the lasso. At the opening of the capsule there is usually a plasmic lid. Within the capsule there is a gelatinous, not fluid sub- stance, which stains with anilin dyes, swells up in water, and has corrosive, acrid qualities. It is the swelling which expels the lasso. Water enters when the lid is thrown off, or when the beginning of the lasso is protruded in consequence of external pressure. The proximal part of the thread is often stronger, and may then be called the axis body ; it lies straight in the capsule, while the rest of the thread is coiled. Both axis-body and thread may be smooth, or beset with roughnesses, bristles, or spines arranged in three spirals. The smooth thread is doubtless the more primitive. The nematocysts have both a mechanical and a chemical effect. The spines of the axis-body may fix firmly in the victim, and the poisonous gelatinous material may enter the wound. Herr Iwanzoff describes the structure of the cnidoblast in detail — the peripheral layer, the distal fringe of bristles or the single cnidocil, the supporting (non -muscular) processes at the proximal end, and so on. The development is also described. No nematocysts were found in sponges, though Eimer has described their occurrence. Those in Turbellaria are noticed, and those in iEolididae. Coral Reef at Funafuti.! — Such borings as Prof. W. J. Sollas was able to make on this reef lead him to think that its structure is that of a coarse “ sponge ” of coral with wide interstices, which may be either empty or filled with sand. The chief constituents of this sand appear to be large Foraminifera, of the genera Orbitolites and Tinoporus. Though the boring proved a failure, a thorough investigation of the fauna and flora was successfully made, while important soundings were taken by Captain Field, K.N. ; these appear to Prof. Sollas to support Darwin’s theory of the coral atolls, but the bathymetrical limit of coral life is a subject which stands in need of renewed investigation ; our accepted conclusions rest on too frail a basis. Ccelentera of the ‘ Caudan ’ Expedition 4 — The report on the Coelen- terates collected by Prof. Koehler in the Bay of Biscay has been drawn * Ex Bull. Moscow, 1896, 99 pp. and 3 pis. t Proc. Boy. Soc. Lond., lx. (1897) pp. 502-12. Nature, lv. (1897) pp. 373-7 (5 figs.). x Kesultats Scient. de la Campagne du { Caudan,’ fasc. ii. (1896) pp. 299-323. 132 SUMMARY OF CURRENT RESEARCHES RELATING TO up by Prof. L. Roule. Forty-five species were collected, and the groups best represented were the Alcyonaria, Antipatliidas, and Hexacoralla. No new species are described, but the collection is of great importance as confirming the doctrine of the extreme uniformity of abyssal, faunae. Funiculina and Kophobelemnon.* — Mr. J. A. Grieg has taken the opportunity of studying a young (175 mm. long) specimen of Funiculina quadrangularis , to compare it with Leptoptilium gracile var. norvegicum , and he comes to the conclusion that they are identical ; but he is careful to limit himself to the variety in question, and does not at present ven- ture to strike out the whole genus and species. The author significantly remarks that it can hardly be a mere accident that two such charac- teristic forms as Funiculina and Kophobelemnon occur in both the Northern and the Southern Seas. Variations in Eucope.f — Prof. A. Agassiz and Dr. W. M‘M. Wood- worth have been engaged in a study of the variations of this jelly-fish, and for that purpose have examined nearly four thousand specimens. Into the statistical details it is, of course impossible for us to enter, but we may say that there is no such general correlation between the number of segments, of genital sacs, of buccal lobes, and of tentaculocysts in Eucope as there is in Aurelia. Neither multiplication nor abortion of parts in Eucope is symmetrical. The suppression of genital sacs, which is rare in Aurelia , is quite common in Eucope. Porifera. Sponges of the ‘ Caudan ’ Expedition.^ — M. E. Topsent dismisses most of the Sponges collected by Prof. Koehler in the Bay of Biscay as “ banales,” but he finds points of interest in Pliegadrella phoenix 0. S., in Hyalonema infundibulum and Leptosia Koehleri, which are new, and in some others ; attention is drawn to the wide geographical distribution of Gellius flag el-lifer of Ridley and Dendy. Non-Calcareous Sponges from Port Phillip Heads.§ — Prof. A. Dendy has published the second part of his catalogue of the Sponges collected at Port Phillip Heads by the late Mr. Bracebridge Wilson. He here deals with the Monaxonid family Desmacidonidae, which are very abun- dant in Victorian waters ; no less than fifty-eight species are here cata- logued, of which twenty-eight appear to be new. For the three new genera which Prof. Dendy finds himself called upon to establish the names Microtylotella , Ampliiastrella and Fusifer are proposed. Protozoa. Foraminifera of the Adriatic.|| — Sig. A. Silvestri has published his first contribution to this subject, which does not appear to have excited the interest of any modern investigator. The author here enumerates sixty-two distinct “ forms ” which belong to forty-six species, and these * Bergens Museums Aarbog, 1896, No. iii., 11 pp. t Bull. Mus. Comp. Zool., xxx. (1896) pp. 121-50 (9 pis.). j Resultats Scient. de la Campagne du 4 Caudau,’ faac. ii. (1896) pp. 273-97 (1 pi.). § Proc. Roy. Soc. Victoria, viii. (1896) pp. 14-51. | |j Atti Acad. Sci. Acireale, vii. (1896) pp. 27-63. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 133 to twenty-two genera ; tlie genus which is far the best represented is Miliolina of Williamson. The author appears to have collected at ten stations. Trypanosomata of Mammalia.* — Dr. J. Rouget has studied Trypano- somata for two years and a half from a series of inoculations in different animals, the original source being a Barb stallion which died of the disease called “ dourine.” Trypanosoma , as observed in the blood of the horse, is an extremely mobile wormlike body composed of homogeneous protoplasm, bounded by an undulating membrane, and having at its anterior extremity a small bright sphere. It is from 18-26 p long and from 2-2*5 p broad. Morphologically it resembles the parasites de- scribed by Lewis, Evans, and Chalachnikow as occurring in the blood of mules, horses, camels, and rats. The author’s attempts at artificial cultivation were unsuccessful. With direct transference from animal to animal there was marked success in the case of white and grey mice, white rats, rabbits, and dogs, while others, such as snakes, lizards, frogs, birds, and bats, were refractory. Mice offer the best field for the study of the parasite, which swarms in the blood a few hours after inoculation. In rabbits, dogs, and horses there is marked affection of the genitalia. The parasite was never found in sections of viscera and organs of animals affected with the disease. Very good preparations of the parasite are easily made in blood-films on cover-glasses, the best stain being eosin and methylen- blue after Chenzinski’s method. The best fixative is alcohol, or equal parts of ether and alcohol. * Ann. Inst. Pasteur, x. (1896) pp. 716-28 (3 figs.). 131 SUMMARY OF CURRENT RESEARCHES RELATING TO BOTANY. A. GENERAL, including tlie Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-Structure and Protoplasm. Structure and Physiology of the Cell.* — According to researches made on vegetable cells ( Anacharis , Hydrodictyon ) by M. M. Tswetfc, strongly plasmolytic solutions determine the accumulation in the proto- plasts of the polioplasm (the circulating portion of the cytoplasm) and of the plastids included in it. To this process he applies the term plas - mosynagy. It is a phenomenon of irritability, a vital reaction of the protoplasm to plasmolytic irritation. The chloroplasts ( Elodea ) are composed of a network of dense re- fringent substance ( chlorojplastin ), the sole support of the chlorophyll, and of an uncoloured interstitial substance ( metaxin ) ; both substances are of a proteid character. Tlie chloroplasts have no differentiated proto- plasmic membrane resembling that of the vacuoles. Their chemical composition varies with the season of the year. Non-Nucleated Cells.j — Herr J. J. Gerassimoff states that cells without a nucleus can be obtained, not only, as previously indicated, by exposure to a low temperature during the process of cell-division, but also by the action of certain reagents, as chloral hydrate, ether, or chloroform. The daughter-cell which contains no nucleus exists only for a short time, but contains normal chlorophyll-bands of a somewhat darker colour, and may form starch in the light. These phenomena had been observed chiefly in Spirogyra, but occur also in Zygnema. Influence of Traction and Pressure on the direction of Partition- Walls. :j; — As the result of experiments on potatoes and on tap-roots, Herr L. Kny confirms, as a general rule, Hofmeister’s law that the position of newly formed septa is determined by the preceding growth, the dividing-wall standing at right-angles to the direction of the strongest previous growth of the cell. This is, however, modified by the law that the orientation of the nuclear figure, and consequently that of the septum, may be affected by giving an arbitrary direction, through traction or pressure, to the preceding most intense growth. (2) Other Cell-contents (including Secretions). Formation of Secretions. § — According to Prof. A. Tschirch, resin, oil, and other secretions are never formed within the cell-membrane, but in a special layer known as the resinogenous layer. The septa which occur in the vittse of Umbelliferse are remains of this layer. The sub- stance of the layer, which the author calls vittin , is of a pectinaceous * Arch. Sci. Phys. et Nat., ci. (1896) pp. 228-60, 467-86, 565-74 (1 pi.). t ‘ Ueber ein Verfaliren kernlose Zellen zu erkalten,’ Moskau, 1896, 4 pp. X Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 378-91 (2 figs.). § SB. 68 Yers. Deutscker Naturf. u. Aerzte. See Bot. Centralbl., Ixviii. (1896) p. 212. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 135 character, and appears to be identical with the substance of mucilage. In schizo-lysigenous oil-passages, like those of the Rutaceae, there is first a cap-like formation of the resinogenous layer, followed by a dissolution of the cells, and a resorption of the protoplasm. Encapsuling of Starch-Grains.* * * § — In the lowest of the three layers which Macchiati describes f as constituting the testa of the seeds of Vida narbonensis — a description which applies equally to the seeds of all Leguminosae — Dr. L. Buscalioni finds starch-grains which display the curious phenomenon of encapsulation. Some of the cells of this tissue contain single starch-grains of colossal size, while in others are a number of much smaller grains. Connecting these grains with the protoplasm in which they lie is a ring composed of a substance coloured brown by tannin, consisting of short rods placed perpendicularly to the plane of the ring. This peculiar membrane is formed with great rapidity. A similar phenomenon, but not so well marked, was observed in the seeds of Eschsclioltzia californica. Peculiarity of Soluble Starch4 — Prof. W. Beijerinck remarks that soluble starch in aqueous solution will not mix with an aqueous solution of gelatin even at boiling heat. When the two are shaken together an emulsion is formed — an emulsion of gelatin droplets in starch solution. The gelatin droplets in their turn contain very minute starch droplets, as may be shown by treatment with iodine and microscopical inspection. It is quite possible that this observation may lead the way to new researches and new views as to the nature of colloidal bodies. Reserve-Stores of Seeds.§ — M. E. Couvreur finds that during the ripening of the seeds of Pidnus, the stores of oil and starch have a parallel increase. Even when separated from the plant, the seeds show for a time an increase in reserves, the increase of oil and starch being still parallel. The author compares this to the increase of glycogen within the silkworm chrysalis. During germination, the starch dis- appears very rapidly, the oil much more slowly. Arrow-Poisons. || — Herr L. Lewin gives a detailed account of the source of the various poisons used for arrows. The order from which the greatest number are derived, is the Apocynaceae ; next follow the Legu- minosae, Loganiaceae, and Euphorbiaceae. Among the Apocymaceae, the most important poisons are obtained from the genera Adenium , Aco- hanthera , and StropJianthus ; of Leguminosae, the genera Erythrophloewn and Physostigma supply the most important poisons. Antiaria toxicaria (Moraceae), Pothos (Araceae), Aconitum , and Helleborus also yield im- portant arrow-poisons. (3) Structure of Tissues. Influence of Fruit-bearing on the Development of Mechanical Tissue.lF — Mr. A. J. Pieters has made a series of experiments on this * Malpighia, x. (1896) pp. 479-89 (1 pi.). t Cf. this Journal, 1892, p. 63. t Centralbl. f. Bakteriol. u. Parasitenk., 2te Abt., ii. (1896) pp. 697-9. § Ann. Soc. Linn. Lyon, xlii. (1896) pp. 145-8. H ‘Die Pfeilgifte,’ Berlin, 1894, 152 pp. See Bot. Centralbl., Ixviii. (1896) p. 328. 1 Ann. Bot., x. (1896) pp. 511-29. 136 SUMMARY OF CURRENT RESEARCHES RELATING TO subject, in the case of some fruit-trees, especially varieties of the appler pear, peach, and plum. Among the conclusions arrived at are the follow- ing : — One-year old fruit-bearing shoots of the apple and pear had less wood in proportion to their diameter than vegetative shoots of the same age. This is largely due to an increase of the cortex of the fruit-bearing shoot, which is also well supplied with supplementary mechanical tissue. In the peach, the fruit -bearing has more wood than the vegetative shoot. The effect upon the tissues is generally local. This local effect of fruit- bearing tends to an increase of cells, with a decrease in the thickness and lignification of the walls of the xylem-cells. In all cases the in- crease in growth is greatest on the side nearest the fruit-stalk. The local effect of fruit-bearing on the xylem-cylinder disappears with time. Fruit-bearing has a temporary local effect on the lignification of the walls of the xylem-cells, preventing it wholly or in part, according to their distance from the fruit-stalk. The lignification of other cell-walls is promoted by fruit-bearing. Fibrovascular Bundles of Nymphseacese.* — Further examples of the occurrence of several steles in the Nymphaeacese are given by Mr. D. T. G wynne- Vaughan, in the stalks or stolons which bear small tubers at their ends in Nymphsea flava and tuberosa. The tubers bear buds, which grow into fresh rhizomes, containing six or seven vascular bundles. Endoderm and Pericycle in Trifolium.t — Dr. S. Belli has made a very detailed study of the stele-theory in reference to the genus Trifolium. Histogenetic researches lead him to conclude that in Trifolium there is no pericycle in van Tiegliem’s sense. The elements referred to this layer belong to the bast and to the interfascicular cambium. A general endoderm and pericycle arc to be found only in the liypocotyl; after that disappears there is none. The memoir concludes with a general criticism of the stele-theory. Anatomy of the Stem of Macrozamia.J — Mr. W. C. Worsdell calls attention to the resemblances and differences in the structure of the stem of Macrozamia as compared with that of other genera of Cycadese. The pith possesses a well-developed network of vascular bundles similar to that of Encephalartos ; it has a distinct adventitious origin, and is not directly continuous with the primary leaf-trace system. The normal cylinder is surrounded by two or three anomalous zones of secondary thickening, the innermost of these being the best developed. The stem is characterised by the presence of a tertiary cambium, producing bundles with inverted orientation. In the abeve points the author points out the resemblance to the fossil group Medullosse. Other characters are referred to which are characteristic of the genus, viz. the presence of leaf-traces in the cortex, which run directly inward to the vascular rings after very short courses ; the structure of the girdles during their tan- gential course ; and the structure and mode of action of the periderm at the [periphery of the cortex ; the phelloderm being largely composed of stone-cells, and producing subsequently a second phellogen in its midst. * Ann. Bot., x. (1896) pp. 624-5. Cf. this Journal, 1896, p. 537. t Mem. R. Accad. Sci. Torino, xlvi. (1896) pp. 353-441 (6 pis.). t Ann. Bot., x. (1896) pp. 200-20 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 137 Anatomy of the Zingiberacese.* — Herr W. Futtercr has investi- gated the anatomy and development of the stem, leaf, leaf-slieath, and root, in many species of Zingiberaceae. The following are some of the more important general results. Where the leaf possesses a hypodermal tissue, the epiderm consists of small cells ; but where the hypoderm is wanting, which is uncommon, the epidermal cells are considerably larger, and assume the form of hypodermal cells. There is almost always a clear differentiation between palisade-cells and spongy parenchyme ; rarely does one pass into the other. In the interior of the stem there is, in almost all the species, an inner sheath, composed of from one to six layers of small cells, usually running in a regular circle parallel to the periphery of the stem. The structure of the rhizome resembles that of the aerial stem, but is simpler. The crystals of calcium oxalate belong to the monoclinic system ; they are never in the form of raphides. Nearly all the species examined possess in the mesophyll of the leaf cells filled with a volatile oil. The hypoderm is especially charac- terised by the presence of tannin. The growing-point of the stem is the result of the activity of a meristematic layer. Structure of Dipterocarpaceae.f — Prof. Sir D. Brandis describes in detail the structure and geographical distribution of this arborescent order, of which the most marked characteristics are the vascular bundles in the cortex and the resin-passages. The latter contain a volatile oil wThich hardens in the air into a resin. Structure of Umbelliferae.J — From the anatomical structure Prof. O. Drude classifies the genera of Umbelliferae in three groups, — the Hydrocotylineae, Saniculineee, and Apioineae. In the first section there are no oil-passages ; the fruit has a woody endocarp covered with cells that contain crystals. In the second section there is no woody endocarj), and the oil-passages are generally wanting. The Apioineae, in which oil- passages are always present, are again divided into a number of families. Anatomy of 0nagrace8e.§ — From a study of the anatomy of the stem of several genera of Onagraceae, Mr. F. Bamaley draws the con- clusion that no anatomical characters can be used to distinguish the species, or even the genera. Bicollateral vascular bundles were found in all the species examined. Intraxylar phloem-islands occur in the stems of all the robust species. Baphides of calcium oxalate are also present ; generally in the cortex or pith, often in the peri cycle and phloem. Anatomy of Betulace9e.|| — From their anatomical structure M. A. M. Boubier divides the Betulaceae into two groups, the Betuleae and Corylese ; the former comprising Betula and Alnus, the latter Corylus and Carpinus . The fibrovascular system of the leaf is open in Betula , closed, at least at the base of the lamina, in the other genera. Various other anatomical characters of the stem and leaf are given, by which the genera can be distinguished. * Bot. Centralbl., Ixviii. (1896) pp. 241-8, 273-9, 346-56, 393-400, 417-31 ; lxix. (1897) pp. 3-10, 35-46 (1 pi.). t SB. Niederrkein. Gesell. Bonn, 1896, pp. 4-42. t SB. 68 Vers. Deutscher Naturf. u. Aerzte. See Bot. Centralbl., Ixviii. (1896) p. 211. § Minnesota Bot. Studies, 1896, pp. 674-90 (3 pis.). || Malpighia, x. (1896) pp. 349-436 (24 figs.) (French). 138 SUMMARY OF CURRENT RESEARCHES RELATING TO (4) Structure of Organs. Anatomy of Loranthaceae.* — Mr. F. W. Keeble calls attention to the following anatomical details in the Cingalese Loranthaceae. In Loranthus neelglierensis the hypocotyl of the fully developed embryo is densely covered with green columnar emergences, the cortical cells of which contain chlorophyll, starch, and tannin. A single stomate occurs on the free surface of each emergence. In this species there is not, as in most, a well-developed suctorial disc at the free end of the hypocotyl, the sucker obtaining entrance in another way. Floral Leaves without Vascular Bundles.f — H. P. van Tieghcm applies the term meristele to the branch of the cauline stele which enters the lamina of the leaf, and there branches into the veins. He further states that the non-ovulate orders of Phanerogams comprised in the LoranthineaB, which exhibit such remarkable simplicity of structure in other ways, are further characterised by a frequent entire absence of meristele in the foliar leaves ; these being then reduced simply to cortex and epiderm. In the majority of the dicblamydeous families, the Loranthaceae, &c., this is the case with the sepals. In those in which the corolla is wanting, the Viscaceae and the Arceuthobiaceae, the calyx is not reduced to this simple condition, but reduction is frequently presented by the stamens. In the Arceuthobiaceae and Balanophoraceae, again, the carpels present a similar simplicity of structure, being entirely destitute of meristele. Variation in Flowers of Salix.J — Dr. W. Haacke has studied the variations which occur in the groups of catkins borne by branches of Salix caprea when the undergrowth of the tree has been cropped for years. The main catkin of a group gives up its female character much less frequently than the accessory catkins, and the apex of the catkin loses its female character much more readily than the other part. Both facts are explained as due to differences of position in relation to nutritive supply. From the fact that definite forms, e.g. male flowers, occur at definite places, Dr. Haacke argues in favour of the definiteness of organic reactions. Protection of Pollen from Rain.§ — Prof. A. Hansgirg classifies under four types the flowers in which the pollen is protected against rain by phytodynamic contrivances, viz.: — (1) Flowers which close their perianth in rainy weather, so as to prevent the entrance of rain-drops without changing the position of the flower-stalk or stalk of the in- florescence. (2) Flowers with erect flower-stalks, which curve in rainy weather so as to alter the position of the opening of the corolla and pre- vent the access of rain to the pollen and nectar. (3) Flowers in which a curvature of the axis or stalk of the inflorescence serves the same purpose of protecting the flowers against the access of rain. (4) Flowers which are erect and open in fine weather, but, during rain, both close their perianth and at the same time protect the pollen by a curvature of the flower-stalk. * Ann. Bot., x. (1896) pp. 626-7. t Rev. Gen. de Bot. (Bonnier), viii. (1896) pp. 481-90. Cf. this Journal, 1896, p. 327. X Biol. Centralbl., xvi. (1896) pp. 817-25 (8 figs.). § Oesterr. Bot. Zeitscbr., xlvi. (1896) pp. 357-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 139 Twisting* * * § of Filaments.* — Herr I. Robinsohn calls attention to the peculiar torsion of the filaments of some of the stamens in some Labia- tiflorae (Labiatae, Scrophulariaceae, Acanthaceae) and Irideae ( Gladiolus ). This appears to be connected with contrivances for pollination. In Digitalis , e.g., the two shorter filaments are quite straight, while the two longer ones are twisted in their lower part, the effect of the torsion being to bring the anthers of the longer filaments into a position imme- diately above those of the shorter filaments, where the pollen will be carried away by the visiting insects from the proterandrous anthers while the stigmas in the same flower are still closed. Elongation of the Axis.f — Herr E. Ule describes the remarkable elongation of the flower-stalk after flowering which takes place in a Brazilian orchid, Wullschlaegelia Ulei, but only if the flower has been fertilised. The purpose of the growth appears to be the dissemination of the seeds. Similar elongations of the flowering axis occur also in CJievreulia acuminata (Composite) and TJtricularia nelumbifolia. Xerophilous Plants. J— Herr Grevillius has studied the character- istics of the xerophilous vegetation of the Swedish island of Oeland. The most prominent are a csespitose habit, shoots or rosettes of leaves growing closely adpressed to the soil, and the great thickness of the leaves in proportion to their surface. Protection against excessive transpiration is afforded by a clothing of hairs, a covering of wax, or the thickening of the cuticle. The mechanical tissue in the lamina of the leaves is either feebly developed or entirely wanting. The internodes of the stem are generally shorter. Leaves of Xerophilous Plants. § — Herr B. Jonsson describes a peculiar form of leaf characteristic of certain tropical xerophilous genera, consisting in a great reduction of the assimilating tissue and a great development of tbe system for protection against transpiration. The palisade-parencliyme consists of a single layer of cells ; the chloro- plasts are usually few, but of large size ; the upper half of each cell is usually destitute of chlorophyll-grains, and often contains a cluster of crystals of calcium oxalate. This peculiar position of the chlorophyll- grains does not change with the varying direction of the light, and is apparently connected with the storing up of acids in the aquiferous tissue which lies above this layer. Structure and Function of Stomates.||— Herr H. C. Schellenberg classifies stomates under two types, viz. : — (1) The Amaryllis- type, in which each guard-cell may be regarded as a sac with two thickening- bands on one side only of the opening ; (2) the IZeZZe&orMS-type, in which the cavity of the guard-cell presents, on transverse section, an inequilateral obtuse-angled triangle. As concerns their function, the author regards stomates as assisting in assimilation, in transpiration, and in the interchange of gases, the * Oesterr. Bot. Zeitsclir., xlvi. (1890) pp. 393-401 (1 pi.). f Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 255-60 (1 fig.). % Engler’s Bot. Jahrb., xxiii. (1896). See Bot. Centralbl., lxviii. (1896) p. 223. § Acta Univ. Lund, xxxii. (1896) 20 pp. and 2 pis. See Bot. Centralbl., lxviii. (1896) p. 324. 11 Bot. Ztg., liv. (1896) l,e Abtheil., pp. 169-85 (1 pi.). 140 SUMMARY OF CURRENT RESEARCHES RELATING TO first of these functions being indicated by the presence of chlorophyll in the guard-cells. He supports the view of Schwendener,* that the opening and closing of the stomates is brought about by changes in the turgor of the guard-cells, rather than that of Leitgeb,t that an important part in this process is played by the adjacent colls ( Nebenzellen ), whether these be of the form of ordinary epidermal cells or not. In opposition also to Leitgeb, he finds the stomates to be always closed at night ; light is the only factor in causing the opening of the stomates, and acts through the increase of turgor due to the assimilation of the guard-cells. Stahl’s “ cobalt-test ” for the intensity of assimilation J the author does not regard as wholly satisfactory in determining whether the stomates are open or closed. Tubers of the Artichoke. § — According to Herr G. Meyer, the tubers of the artichoke are formed by the thickening of the lowermost of the stolons which spring from the underground stem. This thickening is due to the activity of the original cambium which produces new masses of parenchyme ; to the production of parenchyme from interfascicular cambium ; and to the subsequent elongation of the parenchymatous cells. Glucose is found in the young tuber ; inulin is a subsequent formation, both in the tuber and in the aerial plant ; starch is found in the vascular bundle-sheath, and disappears only in the autumn from the lower part of the tuber. j8. Physiology. (1) Reproduction and Embryology. Fertilisation of Salisburia.|| — According to Dr. S. Hirase, the mode of impregnation of Salisburia adiantifolia (Ginglco biloba) differs from that of other Conifers, being effected by antherozoids formed within the pollen-tube. The two nuclei resulting from the final division of the generative nucleus of the pollen-tube become transformed, before enter- ing the oospliere, into motile antherozoids. These differ somewhat in form from the antherozoids of the higher Cryptogams. They are ovoid, 82 /x long by 49 fx broad; the nucleus is placed in the middle, and is entirely surrounded by cytoplasm. The head consists of three spiral coils, which are never completely unrolled, and on them are seated a number of cilia ; there is also a sharp tail. As soon as the antherozoids have escaped through the apex of the pollen-tube, they swarm with a rapid twisting movement. The attraction-spheres which accompany the final division of the pollen-tube-nucleus were well observed. Fertilisation of Cycas.^ —Prof. S. Ikeno has made a similar obser- vation with respect to the mode of impregnation in Cycas revoluta. The antherozoids are somewhat larger than those of Salisburia , and consist of a central nucleus completely surrounded by cytoplasm. The head is composed of four coils, and bears a large number of cilia. Two nuclei are found in each pollen-tube, resulting from the division of the generative * Of. this Journal, 1882, p. 216. f Op. cit., 1887, p. 261. J Op. cit , 1895, p. 130. § Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 317-62 (1 pi.). || Bot. Centralbl., lxix. (1897) pp. 33-5. Of. this Journal, 1896, p. 328. Tom. cit., lxix. (1897) pp. 1-3. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 141 nucleus. No swarming motion was actually observed. The phenomena of impregnation in Cycas revoluta resemble those of Salisburia adianti- folia , and differ from those in all other Gymnosperms at present known in this respect, that the pollen-tube does not penetrate deeply into the archegone, but remains at some distance from it, even at the time of impregnation. It would hence be impossible for the male nuclei to impregnate the oosphere were they not previously transformed into motile antherozoids. The conveying fluid is supplied by the water which is copiously excreted by the female organ at the time of impregnation. Cross-Fertilisation and Self-Fertilisation. — Prof. A. Borzi* * * § describes a type of Epacridese, Cystanthe sprengelioides , which is anemophilous, the corolla dropping as soon as it has opened. Mr. C. Bobertson f describes the mode of pollination, and the insect- visitors, in species of Bhus, Bhamnus, and some other genera. In another paper { the same author gives the results obtained from the investigation of the genera Hepatica, Asimina, Podophyllum, Solea, Euonymus, AEsculus, Astragalus, Stylosanthes, Gymnocladus, Spirsea, Gillenia, Viburnum, Symphoricarpos , Aster, Silphium, Heliopsis, Bud- beelda, and Cacalia. In the Crnciferae there are, according to Herr F. Hildebrand, § all gradations between entire self-fertility in Alliaria officinalis and perfect self-sterility in Cardamine pratensis. Mr. B. Fink || records the results of a series of experiments on cas- trating a number of varieties of the tomato, and finds that they are not then visited by bees, which seek them for the sake of the pollen. They were in all cases readily fertilised by cross-pollination. The period required for the pollen-tube to pass through the style after pollination is about 12 hours. M. J. Briquet^ describes the contrivance for entomophilous pollina- tion by bees in Erythronium dens-canis and E. Smithii. Degradation and Transformation of Sexual Organs.** — According to Herr J. Familler, arrest or transformation of the floral organs takes place at various stages of their development ; there may be a great difference in this respect even in different flowers on the same plant. In the male organ the archespore may remain in its primitive condition, although other normal processes of division proceed as usual. In the female organ the embryo-sac is often present when the integument is greatly reduced. The degradation of pollen is usually indicated by the smaller number of grains rather than by their diminished size. Filiform staminodes often exhibit a survival of the formation of an anther in this early stage. Transformed male organs serve for various purposes, such * II Naturalista Siciliano, i. (1896) pp. 65-6. t Bot. Gazette, xxii. (1896) pp. 154-65. X Trans. St. Louis Acad. Sci., vii. (1896) pp. 151-79. § Ber. Deutsck. Bot. Gesell., xiv. (1896) pp. 324-7. || Minnesota Bot. Studies, 1896, pp. 636-43. ! Mem. Soc. Sci. Nat. Cherbourg, xxx. (1896) pp. 71-90 (1 pi.). See Bot. Centralbh, Ixix. (1897) p. 120. ** ‘ Biogenetische Unters. iib. verkummerte u. umgebildete Sexual-organe,’ Miin- sl.en, 1896, 38 pp. See Bot. Centralbl., Ixviii. (1896) p. 404. 142 SUMMARY OF CURRENT RESEARCHES RELATING TO as increased conspicuousness, a guide to tlie visits of insects, tlie formation of nectar, &c. Organs may undergo actual transformation in the course of their development. The author attributes these transformations to an inner force originating in the protoplasm. Influence of Nutrition on the Colour and Sex of Flowers.* * * § — As the result of experiments on Dahlia variahilis and Petunia hyhrida , Herr F. Hildebrand finds that the nature of the soil has a considerable influence on the colour of the flowers in hybrids, a more or less diffused etiolation being the result of a diminished supply of nutriment. The monoecious or dioecious condition of Busciis aculeatus appears also, in part at least, to be determined by conditions of growth. (2) Nutrition and Growth (including: Germination, and Movements of Fluids). Rontgen Rays and Vegetation.}* — Herr N. J. C. Muller asserts that ordinary sunlight contains no Rontgen rays ; their presence not being indicated either by the help of photographic reagents or by any helio- tropic effect on the growth of Lepidium sativum. Influence of Electricity on the Growth of Plants.}; — As the result of a series of experiments made on aquatic plants, M. M. Thouvenin has arrived at the conclusion that a continuous electric current promotes assimilation by accelerating the decomposition of carbon dioxide by the plant. Influence of Electricity on Germination.§— From a series of experi- ments on different seeds, Sig. G. Tolomei comes to the conclusion that currents of electricity of great frequency exercise an injurious effect on the vitality, and consequently on the germination, of seeds ; and that the intensity of this injurious action varies with the species. Germination of Barley.] — Pursuing his investigations on the chemical changes which take place during germination, Herr J. Griiss states that in barley the solution of the cell-walls of the endosperm commences in the neighbourhood of the scutellum, and advances to- wards the apex of the grain, most actively in the outer part : a small portion at the apex usually remains intact. The cell-walls are not dissolved, but corroded ; they are rendered permeable to enzymes by alloolysis. Congo-red stains intact cell-walls an intense red, while those that have been affected take only a slight light-red tint. The starch- grains are attacked only after the corrosion of the cell-wall, and first in the neighbourhood of the scutellum. Diastase may be produced sponta- neously in the endosperm of ungerminated seeds from which the embryo has been removed. Influence of Nitrogen on the Formation of Roots.! — As a result of a series of experiments on the growth of different plants in soils contain- * Ber. Deutsch. Bot. Gesell, xiv. (1896) pp. 327-31. f Tom. cit., Gen.-Versamm.-Heft, pp. 66-72 (1 pi.). j Bev. Gen. de Bot. (Bonnier), viii. (1896) pp. 433-50 (9 figs.). § Malpighia, x. (1896) pp. 493-511 (3 figs.). || Wochenschr. f. Brauerei, 1896, 4 pp. and 1 pi. See Bot. Centralbl., lxviii. (1896) p. 323. Cf. this Journal, 1896, p. 652. ^1 JB. d. Versuchs-Stat. in Wadensweil, iv. pp. 48-52. See Bot. Centralbl., lxviii. (1896) p. 298. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 143 ing or destitute of nitrogenous substances, the late Prof. B. Miiller- Thurgau concludes that nitrogen has both a direct and an indirect influence on the growth of plants; the former by the supply of material for the formation of proteid substances ; the latter by increasing the strength of the root-system, and thus enabling the plant to draw a larger amount of nutriment from the soil. Antidromy.* * * § — Mr. G. Macloskie gives further illustrations of this mode of growth, both dextrorse and sinistrorse. A forking rootstock (in Nuphar ) may produce antidromic plants on the two branches of the fork. The same phenomenon is illustrated in the stem of the fossil Lepido- dendron Sternbergii , and in the cones of Encephalartos Altensteinii. Ascent of Water in Trees. — Prof. F. Darwin gives a resume of all the more important observations and theories on this subject, including those of Sachs, Boehm, Strasburger, Schwendener, Dixon and Joly, and Askenasy,f pointing out the great importance of the discovery of Dixon and Joly that a confined column of water possesses a power of resisting tensile stress. According to the most modern views, imbibition, this re- sisting power of suspended threads of water, and the turgescence of the cells of the mesophyll, all play their part in the phenomenon. Prof. S. H. Y ines J calls special attention to the fact that a very considerable suction-force is developed by a branch independently of leaves or of life ; this force continues even after the branch has been actually killed. Prof. Joly § sums up his and Mr. Dixon’s conclusions as follows : — We have in the tracheal system of the plant a water-way which is freely open to water-movement, while closed to the movement of free gas. Every bordered pit is an open door to the sap, and a closed one to the gas-bubble, and one wdiicli locks and bars itself against the exit of an imprisoned bubble. In a word, it is a structure semi-permeable towards matter in the three states — the solid, the liquid, and the gaseous. Transpiration. || — Herr E. Krober contests the statement of Miiller- Thurgau that the energy of transpiration of a plant may be taken as the measure of its capacity for absorbing water. The amount of transpira- tion for different branches of the same tree differs as widely as that for different individuals of the same species, or even as much as that for different species. The energy of transpiration depends largely on the external conditions, both at the time of observation and at preceding periods. (3) Irritability. Transmission of Irritation in Sensitive Plants.! — Prof. D. T. Mac- Dougal describes an arrangement by which the effect of increased or decreased pressure on the sensitiveness of sensitive plants can be ob- * Bull. Torrey Bot. Club, xxiii. (1896) pp. 420-3, 536-7. Cf. this Journal, 1896, p. 541. f Ann. Bot., x. (1896) pp. 630-43. Cf. this Journal, 1895, p. 550. i Tom. cit., pp. 644-7. Cf. this Journal, 1896, p. 650. § Tom. cit., pp. 647-60. Cf. this Journal, 1896, p. 542. t| Landwirthsch. Jahrb., xxiv. (1895) pp. 503-37. See Bot. Centralbl., 1896, Beih., p. 330. ! Bot. Gazette, xxii. (1896) pp. 293-300 (1 pi.). Cf. this Journal, 1896, p. 89. 14 i SUMMARY OF CURRENT RESEARCHES RELATING TO served. A fresli series of experiments on Mimosa pudica and Oxalis sensitiva confirm his previous statement that the irritation is not trans- mitted through the vesicular cells, and lead to the following conclusions. Impulses may be transmitted through dead portions of stems or petioles in which the conditions are such that a transmission by the cell- wall or the water in the wall only is possible. Great variations in the pressure exerted on portions of the plant in such manner as to set up hydrostatic disturbances extending throughout the entire plant are not followed by reactions ; hydrostatic disturbance, therefore, does not constitute an impulse. Irritability of Catasetum.* * * § — Mr. J. H. Hart contests Darwin’s state- ment of the irritability of the flowers of Catasetum tridentatum. He states that the ejection of the pollinia can be caused by other means than the irritation of the “ antennas ” by insects ; a concussion of the flower, the removal of the anther-cap, or pressure exerted on almost any part of the column, and especially any irritation on the margins of the stigmatic pit, will effect this readily if the flower is at a favourable stage of maturity. The expulsion of the pollen does not depend on any special irritability, but on mechanical action alone. The “ antennae ” are merely a pro- longation of the edges of the stigmatic pit. When the flower opens, they become turgid, stiff, and non-elastic. In this state they furnish levers which are amply sufficient to cause a disturbance of the grip they hold on the margin of the caudicle. Gamotropic and Carpotropic Movements of the Flowers of Grasses.! — Prof. A. Hansgirg finds a common type of these movements to be that displayed by Avena, in which the flowers, which are closely crowded together in the bud-condition, become widely separated from one another before flowering by the curving of the flower-stalk or of the axis of the raceme or panicle. After flowering, the ripening fruits may either remain in the same position, or may revert to that which the buds occupied before flowering. A large number of species are mentioned in which the carpotropic movements are especially conspicuous. Phyllocarpy.J' — By this term, Prof. A. Hansgirg proposes to desig- nate the movement which takes place of the flower-stalk, after flowering, in many climbing plants ( Tropseolum , Cobsea, &c.), by which the ripening fruit is hid in the foliage for its better protection. (4) Chemical Changes (including Respiration and Fermentation). Formation of Proteids from Asparagin.§ — By a series of experi- ments, chiefly on Lemna, Herr B. Hansteen has determined that when asparagin and grape-sugar occur together in the same cell, they combine rapidly, the result being the formation of proteids. If, however, the grape-sugar is replaced by cane-sugar, no considerable chemical combi- nation takes place. The contrary is the case with glycocoll ; with grape- sugar, this amide is inactive, while with cane-sugar, an abundant forma- * Bull. Misc. Inform. R. Gard. Trinidad, ii. (1896) p. 225. See Bot. Gazette, xxii. (1896) p. 505. t Oesterr. Bot. Zeitschr., xlvi. (1896) pp. 320-5. Cf. this Journal, 1893, p. 69. X Oesterr. Bot. Zeitschr., xlvi. (1896) pp. 401-2. § Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 362-71. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 145 tion of proteid takes place. In the formation of proteids from grape- sugar, ammonium chloride or sulphate may take the place of asparagin. Contrary to the statement of some other observers, Hansteen asserts that light has no, or very little, direct influence on the formation of proteids. Formation and Dissolution of Hemicellulose.* — Dr. J. Griiss has studied the formation and dissolution of cell- walls composed of cellulose, and its connection with the formation of gum. He states that the hemi- celluloses mannan, galactan, and araban are formed directly or indirectly as reserve-substances. In the first case, this takes place as thickened walls in the endosperm ( Phoenix , Phy telefilms), or as secondary thick- ening-layers in libriform and wood-parenchyme cells ( Primus , Acacia , Astragalus). They take the form of indirect reserve-substances when they compose the walls of starch-bearing cells, as in the endosperm of grasses. In a cell-wall composed of a mixture of two hemicelluloses, one of the two constituents is decomposed sooner than the other by the action of diastatic enzymes. The hemicelluloses galactan and araban are transformed by enzymes into the gums arabin and galactin, and may pass as such into the tissue before they become converted into the sugars arabinose and galactose. These gums occur in the dormant re- serve-reservoirs in PrunuSj Acacia, and Astragalus , and may be termed “ reserve-gums.” Respiration of Wounded Plants.f — Mr. H. M. Richards gives the results of a series of experiments on the effect of injury to the tissue on respiration in the case of a number of plants, the potato, bean, carrot, and others. The general immediate result of injury is a greatly increased respiration, falling to the normal intensity as the wound heals. This increase may be ascribed to an effort on the part of the plant to recover from the injury, by which the ordinary functions are stimulated, thereby necessitating an increased supply of oxygen. In bulky tissues there is, in the natural condition, a certain amount of enclosed or absorbed carbon dioxide, some of which is given off very suddenly during the first two or three hours after injury. The ratio of the absorption of oxygen and production of carbon dioxide does not appear to vary within very wide limits before and after injury. The amount of oxygen absorbed is always in excess of the amount theoretically required for the quantity of carbon dioxide evolved. Nitrification. — In confirmation of previous results Herr E. Godlewski J concludes, from a fresh series of experiments, that nitrifying organisms derive their carbon from free carbon dioxide and not from carbonates. The amount of free nitrogen produced varies with the conditions of the experiment. As the result of experiments M. Mareille § states that the energy with which a soil is nitrified depends not only on the temperature, aeration, and humidity of the soil, and on the energy of the organisms present, but also on the nature of the organic matter to be nitrified. * Biblioth. Bot. (Luerssen u. Frank), Heft 39, 1896, 15 pp. and 1 pi. t Ann. Bot., x. (1896) pp. 531-82 (2 figs.). % Anzeig. Akad. Wiss. Krakau, 1895, pp. 178-92. See Journ. Ohem. Soc., 1896, Abstr., p. 6(J8. § Ann. Agron., xxii. (1896) pp. 337-14. See Journ. Chem. Soc., 1896, Abstr., p. 669. 1897 L 146 SUMMARY OF CURRENT RESEARCHES RELATING TO In tlieir works on the micro-organisms of nitrification Herren A. Stutzer and B. Hartleb * * * § have alluded to a mould-fungus characterised by a much-branched mycele, and by having both mega- and microspores. In the three stages of development the fungus exerts different actions. Hence, for exciting definite effects, the composition of the medium and the presence or absence of atmospheric air are of great importance. Under certain circumstances the fungus lives on organic nitrogenous compounds, and is then able to set up nitrification directly, under other conditions to produce nitrite, and under still others nitrate. The mycele may split up into indifferent cells which resemble bacteria. B. CRYPTOGAMIA. Muscineae. Rhynchostegium.f — Sig. U. Brizi gives a monograph of this genus of Musci, which he divides into two subgenera, Eurhynchostegium and Eiirhyncliium. Twenty-eight species in all are described, with a large number of sub-species and varieties. There are two new species, B. romanum and Pirottse. Itabenhorst’s Cryptogamic Flora of Germany (Musci>4 — Parts 28-30 of this important work by Herr K. G. Limpricht are still occupied with the Hypnacese. After the completion of Brachythecium , the following genera are treated of : — Bryhnia (1 sp.) ; Seleropodium (4 sp.) ; Hyocomium (1 sp.) ; Eurhynchium (21 sp.) ; Bhynchostegiella gen. n. (5 sp.), with the following diagnosis : a central bundle, leaves narrowly lanceolate, not or scarcely decurrent, basal cells not broadened, rib single, cells of the leaf-wings not or scarcely different from the basal cells, stomates 2-celled, epidermal cells collenchymatous, seta curved, usually warty ; Bhynchostegium (6 sp.) ; Bliapliidostegium (2 sp.) ; Thamnium (2 sp.). The third group, Hypnese, then follows, consisting of the genera Plagiothecium , Amblystegium , Hypnum , and Hyloconium , and a commencement is made of Plagiothecium with 18 species. Development of Geothallus.§ — Pursuing his investigations into this new genus of Hepaticee, Prof. D. H. Campbell describes in particular the germination of the spores and bulbils, and the structure of the antherid and archegone, as well as that of the sporogone. He regards the genus as most nearly allied to Sphserocarpus , agreeing both with that genus and with Biccia in the form of the apical cell, and the general position and structure of the sexual organs, including the characteristic envelope with which each is surrounded. In the structure and development of the sporogone there is a close resemblance between Sphserocarpus and Geothallus. Geothallus differs from Sphserocarpus chiefly in the more massive thallus, the sessile archegone, the development of true leaves, and the formation of bulbils by which the plant becomes perennial. It has also some affinities with Fossombronia, and may be regarded as intermediate between that genus and Sphserocarpus. * Centralbl. f. Bakteriol. u. Parasitenk., 2te Abt., ii. (1896) p. 701. f Malpighia, x. (1896) pp. 227-57, 437-78 (1 pi.). X Cf. this Journal, 1896, p. 212. § Ann. Bot., x. (1896) pp. 489-510 (2 pis.). Cf. this Journal, 1896, p. 441. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 147 Characese. Bulbils of the Characeae.* — Dr. K. Giesenhagen has studied the structure and mode of formation of the clusters of bulbils formed at the nodes of the roots of various species of Chara, especially G. stelligera, aspera , baltica , and fragifera. Their development is fully described in the case of C. aspera. The bulbils in this species occupy a somewhat intermediate position in structure between the truly unicellular bulbils of Lamprothamnus alopecuroides and Lychnothamnus macropogon, and the multicellular bulbils of Chara baltica , fragifera, and delicatula. The remarkable regularity and uniformity which characterises the structure of the Characeae in other points is not subject to any exception in the case of these organs. Rabenhorst’s Cryptogamic Flora of Germany (CharaceseXf — Dr. W. Migula’s exhaustive and admirable monograph of the Central European species of Characese is now completed. Besides a description of every species and of the very numerous forms of some of the species — all of the former and many of the latter being admirably figured — it contains a full account of the morphology and history of development of the family, an essay on the position of the Characese in the natural system, an account of their geographical distribution, and instructions as to their collection, examination, and determination. All the non-German Euro- pean species are also referred to. Algae. Klebs on Reproduction in Algse andFungi.J — In this most important work Dr. G. Klebs gives the results of many years’ observations on the relation between the sexual and non-sexual modes of propagation in certain Algse and Fungi. He finds that, as a general law, it is the ex- ternal conditions which determine the production by any species of zoospores on the one hand, or of gametes on the other hand. With Vaucheria , zoospores are always produced when filaments which have been kept moist for some days are soaked with water, or when they are removed from a dilute nutrient solution into pure water, or when cultures in water or in a very dilute nutrient solution are darkened. If the filaments are placed in a 2-4 p.c. solution of cane sugar in bright light, gametes are always produced. Similar results were obtained with Hydrodictyon and some other Algae. In Spirogyra parthenogenetic resting-spores can be produced by placing filaments with long conjuga- ting-tubes in a strong solution of sugar. With fungi ( [Eurotium , Mucor) the results are more complicated and less clear than with Algae. Under the name Botrydium granulatum the author asserts that two quite distinct organisms have been confounded. On one of these he founds the new genus Protosiphon, distinguished from Botrydium by its propagation by means of gametes and non-motile spores instead of by uniciliated zoospores. * Flora, lxxxii. (1896) pp. 381-433 (1 pi. and 25 figs.). t Vol. v. Die Characeen, Leipzig, 1897, 765 pp. and very numerous figs. Cf. this Journal, 1896, p. 212. X ‘ Die Bedingungen d. Fortpflanzung bei einigen Algen u. Pilzen,’ Jena, 1896, 543 pp., 3 pis. and 15 figs. 148 SUMMARY OF CURRENT RESEARCHES RELATING TO Verticillate Ramification.* * * § — M. P. van Tieghem points onfc a devia- tion in certain Algae from the ordinary mode of verticillate ramification, where homologous elements are superposed at each node. The excep- tional mode has been observed only in certain Algae belonging to the Florideae ( Ptilota , Euptilota, Pterota, Bonnemaisonia'), and consists in the superposition of homologous elements only in pairs. Agardh’s Analecta Algologica.| — In “ Continuatio III.” of this work Prof. A. G. Agardh establishes four new genera of Algae, viz. : — Homceo- stroma, founded on Punctaria latifolia ; Endarachne, near to Phyllitis ; Hooperia , founded on Chylocladia Baileyana; and Diplocystis ( Agardhinula De Toni), on Callophyllis Brownese. The trichosporanges of Dictyota crenata , the cystocarps of Cordylecladia furcellata, and the antherids of Sarcomenia dasyoides , are described. The genus Cystoseira is divided into three subgenera, — Bapidophora, Thcsiophyllum , and Eucystoseira ; and Liagora into two, — Euliagora and Goralict. Procarp and Cystocarp of Ptilota.j — Mr. B. M. Davis describes in detail the structure and development of the procarp and cystocarp in this genus of Florideae, especially in two American species, P. serrata and plumosa. The structure and development of these organs agree in general features with those of allied genera, e.g. Callitliamnium , Ceramium , &c., but differ in some interesting points ; and the author considers there is strong evidence that the ordinary mode of reproduction of Ptilota is non-sexual or apogamous. In no case were any pollinoids found attached to the trichogyne. The procarp consists of a trichogyne, a carpogenous cell, and an intermediate portion composed of one or two cells, the trichoplioric apparatus. The distance between the trichogyne and the carpogenous cell is so great that it is difficult to conceive of the sexual fusion being transmitted from one to the other without the inter- vention of an ooblastema-filament ; and no trace can be detected of a structure of this character. In P. serrata the cystocarp is always developed from a single carpogenous cell ; in P. plumosa from one of two cells, Thorea.§ — Herr F. P. R. v. Wellheim describes several points in the structure of Thorea ramosissima, especially the gelatinous sheath which envelops both the medullary filaments and the basal cells as well as the monosporangial filaments. The sheaths of the separate filaments are seldom to be clearly distinguished, and have then usually only a single septation ; more often they are more or less confluent. Pilinia and Stigeoclonium.|j — Miss Josephine E. Tilden has cultivated the rare alga Pilinia diluta, and finds it to be a stage in the development of Stigeoclonium flagelliferum or some nearly allied species, which also has a CfisetopJiora-form ( C . pellicula) and a Palmella- form. The Pilinia stage is characterised by a calcareous secretion; bristles are formed under cultivation. In Pilinia the authoress observed conjugation between microzcogametes, resulting in the production of a planozygote. In * Ann. Sci. Nat. (Bob), ii. (1S96) pp. 350-71. f Acta R. Soc. Phys. Lund, xxxii. (1896) 140 pp. and 1 pi. X Bot. Gazette, xxii. (1896) pp. 353-78 (2 pis.). § Oesterr. Bot. Zeitschr., xlvi. (1896) pp. 315-20 (1 pi.). I! Minnesota Bot. Studies, 1896, pp. 601-35 (5 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 149 Pilinia the number of megazoospores in a gonidange is usually four ; in Stigeoclonium it may be as high as sixteen. Snow-Flora of Mont Blanc.* * * § — Prof. R. Ohodat records the following low forms of life observed on the snow-field of the Col des Ecandies. An organism corresponding closely to Hsematococcus lacustris , consisting of ellipsoidal cells of a brick-red to purple-red colour, the contents frequently dividing into spores, and producing zoospores under culture. The author considers it probable that Sphserella nivalis is a stage of the same organism. Generically it can hardly be distinguished from Clilamydococcas. A new species, Raphidium nivale , is described, not associated into colonies. A little known desmid Ancylonema Norden- sJcidldii , found also in Norway, was also met with. Fungi. Protoplasmic Connection in Fungi.f — Herr A. Meyer asserts that filaments connecting the protoplasts of adjoining cells are common in the higher Fungi, as in all the larger plants. They are especially readily recognised in the mycele of Hypomyces rosellus, in which cells of the septated hyphas have from 3 to 5 nuclei, and the septa are traversed by protoplasmic threads. The same occurs in the sclerotes of Claviceps purpurea. The cytoplasms of hyphrn which are at first isolated become in this way combined and capable of carrying on a common work. The fusion of the spores in Hypomyces may be compared to that of the myxamoebae into a plasmode in the Myxomycetes. Acid-loving Fungi.J — In dilute solutions of citric acid, Herr C. Wehmer finds a fungus-mycele which he determines as belonging to Verticillium glaucum. In solutions containing tartaric acid, Citrorayces makes its appearance. Renicillium luteum was found when nutrient solutions containing sugar were treated with citric acid ; and Aspergillus niger when tartaric acid was added. Dissemination of Spores by XLain.§— Prof. K. Goebel calls attention to the fact that not only the spores of Mosses, but those also of Fungi (Geaster) are greatly aided in their dissemination by the action of rain- drops. This appears to be the object of the highly hygroscopic property of the fructification. Mucor proliferus sp. n.j] — Under this name Herr W. Schostako- witsch describes a new species readily cultivated on bread or liorse- dung, distinguished by the form of the columel, the mode of branching, the tendency to prolification, and the dimorphism of the sporanges ; those which terminate the main branches being larger and having a thicker wall than those which occur on the secondary branches. Action of Nitrate of Ammonia on Aspergillus niger.H — M. 0. Tanret finds that by doubling or trebling the amount of nitrate of * Bull. Herb. Boissier, 1896, pp. 879-89 (1 pi.). f Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 280-1. X Beitr. z. Kcnnt. einheimischer Pilze, ii. (1895). Sec Bot. Centralbl., 1895, Beih., p. 414:. § Flora, lxxxii. (1896) pp. 480-2. Cf. this Journal, 1895, p. 660. || Ber. Deutscli. Bot. Gesell., xiv. (1896) pp. 260-2 (1 pi.). *11 Comptes Rendus, cxxiii. (1896) pp. 948-50. 150 SUMMARY OF CURRENT RESEARCHES RELATING TO ammonia in Raulin’s fluid, the growth of Aspergillus niger is much altered. At a temperature of 30°-40° C. the mycele grows* profusely, but forms no spores. At 20°-22°, even with 1 gr. of ammonium nitrate to 100 ccm., the fructification is retarded, but is not entirely arrested, while the growth of the mycele still goes ou. The author notes the appearance of free nitric acid in the culture-fluid in which the vegetating Aspergillus is growing. Moreover starch (though not in grains) is formed in the mould, both in light and darkness. Rotting of Fruits.* * § — Herr C. Wehmer asserts Penicillium glaucum to be much the most common cause of the rotting of fruits. In apples and pears it is accompanied by Mucor pyriformis , and in the case of medlars the latter species is the most common fungus. In lemons, oranges, and most tropical fruits, P. glaucum is associated with two other closely allied species, P. italicum and olivaceum. In plums Mucor racemosus was also observed. Botrytis cinerea forms grey tufts on walnuts. This last species and P. glaucum are the common fungi on grapes. Parasitic Fungi. — Messrs. L. M. Underwood and F. S. Earle f clear up the difficult synonymy of the species of Peridermium which are para- sitic on pines. In the eastern United States there are two species which inhabit leaves, P. acicolum and orientale ; and one, P. cerebrum , which is found only on stems, producing extensive gall-like swellings, often of enormous size. M. N. Patouillard J describes a remarkable deformation of a pine- cone produced by the attacks of an apparently new species of Uredineae which he names Cseoma conigenum. A disease of the sugar-cane very similar to that known as “ red-rot ” ( Bothfdule ), is attributed by Herr J. H. Wakker § to the attacks of a new species of Marasmius which he names M. Sacchari. Mr. J. J. Davis || describes a new species of Uredineae Burrillia globu- lifera, parasitic on culms of Glyceria fluitans. Prof. M. C. Pottert details the development and nature of the conidial stage of Botrytis cinerea , a saprophyte which is the initial cause of the rotting of stored turnips. Sugar-Cane Diseases.** — Prof. F. A. F. C. Went gives details of the life-history of two fungi which cause destructive diseases of the sugar- cane, Colletotrichum falcatum and Tkielaviopsis ethaceticus, producing respectively the “ red smut ” and “ pineapple disease.” The first is a saprophyte on the leaves of the sugar-cane, but can become a wound- parasite. It does not appear to produce any other disease besides the red smut of Java. The second is a general saprophyte, behaving sometimes as a wound-parasite, and causing the pineapple disease of J ava. The evi- dence is at present insufficient which proposes to identify this latter * Beitr. z. Kentniss einheimisclier Pilze, ii. (1896). See Bot. Centralbl., Ixviii. (1896) p. 267. t Bull. Torrey Bot. Club, xxiii. (1896) pp. 400-5. X Journ. de Bot. (Morot), x. (1896) pp. 386-8 (1 pi.). § Centralbl. f. Bakteriol. u. Parasitenk., ii. (1896) 2te Abt., pp. 45-56. || Bot. Gazette, xxii. (1896) pp. 413-4. ^ Journ. Board Agric., iii. (1896) 14 pp. and 4 pis. See Bot. Gazette, xxii. (1896) p. 503. ** Ann. Bot., x. (1896) pp. 583-600 (1 pi.). Cf. this Journal, 1894, p. 380 ; 1896, p. 550. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 151 fungus with Trichosphseria Sacchari and Melancomium Sacchari. The author was unable to obtain positive evidence that either of these forms can give rise to the other. Parasites of the Beet.*' — In addition to a number of animal parasites, Herr J. Stoklasa describes the following fungi as attacking the culti- vated beet in Bohemia : — Rliizoctonia violacea, the most destructive of all, the mycele attacking the root, and causing enormous losses ; Cerco - spora beticola, attacking the leaves ; PJioma Betse, the cause of dry-rot ; and Peronospora beticola. Fungi Parasitic on Lichens.f — Prof. W. Zopf gives a detailed list of all the lichens on which parasitic fungi have been observed, amounting to 309 species. The parasites themselves belong to 344 species and 76 genera. In the greater number of cases each fungus attacks only a single kind of lichen, though this is not always the case, Trichothecium pygmseum having been found on as many as forty different species. Similarly each kind of lichen is, as a rule, attacked by only a single species of parasitic fungus, though there are many exceptions also to this rule. Organs of Attachment of Botrytis4 — From a series of observations on Botrytis 'dnerea, Miss M. E. 0. Horn comes to the conclusion that the organs of attachment and the conidiospores are equivalent both physiologically and morphologically, having, in fact, the same origin. The formation of the organs of attachment appears to be determined by external conditions, which may be artificially produced by placing a hard substance in proximity to the hyphae. Development of Teichospora and Ceratostoma.§ — Miss M. A. Nichols describes the morphology and development of these two genera of Pyrenomycetes. In Teichospora no male organ could be detected (in Teichosporella there is a possible rudimentary antherid), and there is no probability of any process of fertilisation. A single cell of the mycele forms, by successive division and growth, a solid sphere of parenchy- matous tissue. Certain of the inner cells of this tissue become en- larged and differentiated into asci. Each ascus contains at first a single large nucleus, which, by successive karyokinetic divisions, fur- nishes a single smaller nucleus for each compartment of the multiseptate spores. In Ceratostoma and Hypocopra the spores, upon germination, send out multinucleated mycelial threads, which become septate, branch, and form circular colonies. Upon the mycele are borne short thick branches, which become curved, or sometimes several times coiled, and perform the function of archicarps. Near these archicarps are usually found long slender branches, the antherids. These intertwine with the archi- carps, and their tips meet and fuse. But in some cases the archicarps appear to develop without fertilisation. The archicarp furnishes, by growth and division, the cells which make up the interior of the peri- thece ; and the asci arise from certain of these cells of the interior. In each young ascus there is a single primary nucleus ; this divides karyo- * Zeitschr. f. Zuckerindustrie in Bohmen, 1896. See Bot. Centralbl., 1896, Beih., p. 464. t Hedwigia, xxxv. (1896) pp. 312-66. X Bot. Gazette, xxii. (1896) pp. 329-33 (1 pi.). § Tom. cit., pp. 301- 28 (3 pis.) 152 SUMMARY OF CURRENT RESEARCHES RELATING TO kinetically, the daughter-nuclei dividing in the same manner, to furnish a nucleus for each spore. Nuclear division probably continues within the spore after the formation of the spore-wall. The wall of the peri- thece is formed from surrounding filaments. Eurotiopsis Gayoni.* * * § — M. J. Laborde describes, chiefly from the physiological side, a new mould which was found growing on starch. The fungus was discovered from the presence of red patches resembling those produced by Micrococcus prodigiosus. Microscopical examination disclosed a red-coloured mycele ramifying through the starch, which in its turn was stained by the pigment secreted by the mycele. Morpho- logically, the new fungus belongs to the Ascomycetes, and it is denomi- nated Eurotiopsis Gayoni sp. n. Besides the mycele and the red pigment, other facts noted are that reproduction is aerial, and the presence of peritheces and conids. Eurotiopsis Gayoni is cultivable on artificial media, Baulin’s fluid being especially suited to it. Certain carbo- hydrates, such as ethylic alcohol, glycerin, mannite, and lactose, are utilisable, while saccharose and inulin are not. The experiments, which are numerous and physiological, show that Eurotiopsis is a most perfect example of the class of fungi connecting on the one hand the moulds which are pure agents of combustion, with the yeasts whose chief function is to effect the alcoholic fermentation of sugar. This ferment function seems highly elastic in Eurotiopsis, as it was found to vary from 1 to 10. Consumption of Acids by Yeasts.f — Herr J. Shukow finds that yeasts are capable of taking up and using citric, malic?5 tartaric, and succinic acids : citric acid is that which is most easily assimilated, then malic, tartaric much less so, and succinic least of all. Different races of yeasts use up different quantities of acid under the same conditions. The intensity of the consumption depends on the presence of nitrogenous substances and of ash ; the richer the medium is in these substances, the better it is for the nutrition of the yeasts, and the more acid they can consume. Fusicladium. — Dr. B. Aderhold J identifies the various parasitic species of Fusicladium as the conidial form of corresponding species of Ventura. F. dendriticum , common on the leaves of the apple, is referred to V. clilorospora , while the ascoform of F. pirinum , parasitic on the leaves of the pear, is erected into a new species under the name Ventura pirina. The identity was, in both cases, established by inoculation. The same author § describes a new species, which he names Fusi- cladium Betulse, parasitic on tbe leaves of several species of Betula, and identifies it as the conidial form of Ventura ditricha f. Betulae. Coleosporium Pini.ll — Prof. B. T. Galloway gives details of the life- history of this fungus, and of the injuries inflicted by it, resulting in a casting of the leaves, on Pinus virginiana , tbe only pine which it attacks in America. The full development of the fungus lasts through twelve * Ann. Inst. Pasteur, xi. (1897) pp. 1-43. t Centralbl. f. Bakteriol. u. Porasitenk., 2te Abt., ii. (1896) pp. 601-12. X Landwirth. Jahrb., 1896, p. 875. See Bot. Centralbl., lxix. (1897) p. 247. § Centralbl. f. Bakteriol. u. Parasitenk., 2te Abt., ii. (1896) pp. 57-9. || Bot. Gazette, xxii. (1896) pp. 433-53 (2 pis. and 3 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 153 months, and during a large part of this time it does not seriously interfere with the functions of the host. The ultimate result of the attacks of the parasite is to rupture the tissue of the leaves, causing excessive evapora- tion. This brings about a loss of turgidity and other physiological changes which lead to the gradual death and casting of the leaves. Melampsora Tremulae.* — According to Herr G. Wagner, different forms of this parasite of the aspen are connected genetically with three distinct aecidioforms, viz.: — (1) Cseoma pinitorquum on Pirns sylvestris, and C. Laricis on Larix europsea ; (2) C. Mercurialis on Mercurialis perennis; and (3) G. Chelidonii on Chelidonium majns. The last two forms he names Melampsora Eostrupii and M. Magnusiana respectively. Rhizoctonia.t — M. E. Eoze calls attention to the frequent con- currence of Phizoctonia Solani and Oospora scabies in potato-plants affected with the scab, and suggests that the chains of small spherical hyaline cells which constitute the latter fungus are a form of fructifi- cation of the Phizoctonia. Tuberacese and Gasteromycetes.* * § — Following out his division of the Tuberacem into the three families, Eutuberineae, Balsamieae, and Ela- phomycetineas, Dr. E. Fischer seeks to draw out a parallel between these and corresponding members of the Gasteromycetes. Parallel forms to the Eutuberineas are to be found among the Gasteromycetes ; on the one hand, in the genera Gautieria and Hysterangium ; on the other hand, in Hymenog aster. But while in the Tuberacese the differentiation does not advance beyond Tuber or Pachyphlceum, the development of the fructifi- cation attains, among the Gasteromycetes, a much greater height in the Clathreae and Phalleae. The Balsamieae may be compared to the Lyco- perdaceae among the Gasteromycetes. Among the Elaphomycetineae, certain families present parallel forms to genera of Sclerodermeae among the Gasteromycetes. Receptacle of Clathrus.§ — Pursuing his investigations on the Phal- loideae, Dr. E. A. Burt now describes in detail the development of the receptacle of Clathrus columnatus , differing in several points from the conclusions of Fischer. || The resemblances and differences between the two families of the Phalloideae, the Phalleae and the Clathreae, are further elucidated ; one of the most important differences is that in the mature stage, the position of the glebe is outside the receptacle in the Phalleae, while it is within it in the Clathreae. The author believes that the Phalleae and Clathreae have both arisen independently from lower forms outside the family ; the highest specialised forms in each family resemble one another from being adapted to the same end. ~ In another paper, ^ Dr. Burt gives a’synopsis of all the Phalloideae of the United States. Actinomycosis.** — Dr. G. Gasperini protests against confounding several quite distinct species of Actinomyces. Bovine actinomycosis is * Oesterr. Bot. Zeitschr., xlvi. (1896) pp. 272-3. t Comptes Eendus, cxxiii. (1896) pp. 1017-9. + Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 301-11. Cf. this Journal, ante , p. 59. § Bot. Gazette, xxii. (1896) pp. 273-92 (2 pis.). Cf. this Journal, 1896, p. 661. || Cf. this Journal, 1891, p. 78. *|j Tom. cit., pp. 379-91. ** Atti Soc. Tosc. Sci. Nat., x. (1896) pp. 144-9. Cf. this Journal, 1896, p. 221. 154 SUMMARY OF CURRENT RESEARCHES RELATING TO not solely due to A. bovis , but to several distinct species ; of which he has isolated A. albus } sulphur eus, and luteo-roseus. In man, infection has been observed by A. albus, asteroides, and carneus. He confirms the opinion that Madura foot is a form of actinomycosis, and that this is not solely due to A. ruber. He shows the aetiological identity of lesions with clavate and those with filamentous forms of the micro-organism ; and emphasises the practical importance of the simulation of true tuberculosis by actinomycosis in man. Protection of the Organism against Blastomycetes.* — Dr. G. Jona injected Saccharomyces apiculatus into the blood-circulation, the peritoneal sac, and beneath the shin of rabbits, for the purpose of ascertaining how the animals get rid of the germs. In the first case, it was found that the Saccharomyces was killed, and finally absorbed by the blood itself, by means of its inherent physiological properties ; thus negativing the supposition that the parasites were excreted by the kidneys, or had be- taken themselves to the viscera. Injections of suspensions of Saccharo- myces cultures in water into the peritoneal sac showed the effect of the agglutinative action of the peritoneal fluid on the parasites, which in a few hours were either destroyed or rendered incapable of reproduction. Similar results were obtained from subcutaneous injections. Myxomycetes. Myxobotrysacese, a new Order of Myxomycetes.f — On the bark of a willow, Herr H. Zukal found an organism belonging to the Myxomy- cetes, Myxobotrys variabilis, which he makes the type of a new order, Myxobotrysacese. The Exosporese are divided into two orders, the Ceratiomyxaceae, of which Ceratiomyxa is the type, and the Myxobotrys- aceae, which are characterised by the spores arising by budding from the plasmode, without any previous breaking up of the protoplasm into dis- tinct portions. In Myxobotrys , the spores are of two kinds, larger and smaller. The former are the result of the creeping plasmode forming itself into nearly spherical branches, which ultimately become elliptical, and transform themselves into spores by the excretion of a delicate membrane. These spores are either sessile on the substratum or on a membranous hypothallus, or have a very short stalk ; the contents are orange-red. In the latter case, the plasmode puts out conical or cylin- drical processes, at the apex of which are developed the ellipsoidal shortly-stalked orange-red spores. The swarmspores and myxamoebae were not observed. The author describes a peculiar process which takes place in the plasmode. At the time when the ingesta are expelled, and the formation of spores begins, the rod-shaped microsomes disappear, and are replaced by a great number of long filaments. According to F. Ludwig, J the alleged new genus is identical with Berkeley’s Chondromyces, placed by Thaxter § in the Myxobacteriaceae, in which Zukal’s Myxobotrysaceae must be merged. Amylotrogus, a new Genus of Myxomycetes.|| — M. E. Roze finds in gangrenous potatoes a parasite which attacks the starch-grains, be- * Centralbl. f. Bakteriol. u. Parasitenk., xxi. (1897) pp. 147-50. t Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 340-7 (1 pi.). X Bot. Centralbl., lxix. (1897) p. 352. § Bot. Gazette, xvii. (1892) p. 389. Cf. this Journal, 1893, p. 370. || Comptes Rendus, cxxiii. (1896) pp. 1323-4 ; exxiv. (1897) pp. 248-50 ; Journ. de Bot. (Morot), x. (1896) rp. 424-6 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 155 longing to a new genus of Myxomycetes, which he names Amylotrogus. It attacks also the starch of wheat, and several distinct species are described. Some of these species develop their plasmodes superficially, others within the starch-grains; in the former case, they frequently branch and anastomose. The plasmodes can retain their vitality for a long period in a desiccated condition. They have a discoid form and a pale violet-red colour. Two species are specially described, A. ramulosus and discoicleus. Cytidium, a new Genus of Myxomycetes.* — In a list of Myxomy- cetes from the Miami Valley, Ohio, Mr. A. P. Morgan describes the new genus Cytidium , with the following diagnosis : — Sporange globose or rarely ellipsoidal, stipitate ; wall a thin membrane, with an external layer of minute granules of lime, ruptured irregularly. Stipe more or less elongated, tapering upwards, and entering the sporange as acolumel. Capillitium of slender tubules, arising from the columel, repeatedly branching and anastomosing to form a regular network, the extremities attached on all sides to the wall of the sporange, the tubules containing at intervals nodules of lime. Spores globose, violaceous. Near Phy- sarum, but distinguished by the columel, which gives origin to the capillitium. Protopliyta. a. Schizophyceae. Reproduction of Marine Diatoms. f — Mr. G. Murray describes a re- markable mode of propagation observed in certain pelagic diatoms chiefly belonging to the genera Bidduljpliia , Coscinodiscus , and Clisetoceros. In Biddulpbia mobiliensis “cysts” were observed within the parent-cell, with only slightly silicified wall, and without the characteristic spines. They appear to have the power of dividing and multiplying before assuming the characteristic parent-form. A similar phenomenon was observed in Coscinodiscus concinnus, but here the protoplasm divides before the production of the “ cysts,” two of which were found within the same parent-frustule, differing from one another in form, and in the width of the girdle-zone. It is not uncommon to find the young Coscinodisci in “ packets ” of eight or sixteen, resulting apparently from further binary division within the frustules, which are found accompanying them in an empty state. These young forms have their membranes either very slightly silicified or not at all, and are, therefore, capable of increasing in size. A similar formation of “ packets ” of eight or sixteen young indi- diduals within the parent-frustule was observed in several species of Clisetoceros. Diatomaceous Earth.J — Mr. T. W. E. David gives particulars of the position and composition of the diatomaceous earth found in various localities in N.S. Wales. He states that they are always found in association with volcanic rocks, probably in consequence of the large amount of silica contained in solution in the hot springs. One of the most important deposits, that of the Warrumbungle Mountains, is asso- ciated with trachytic lavas and tuffs of early Tertiary, possibly of late Cretaceous Age. * Journ. Cincinnati Soc. Nat. Hist., xix. (1896) pp. 1-44 (3 pis.). t Proc. Roy. Soc. Edinburgh, xxi. (1896) pp. 207-19 (3 pis.). Cf. this Journal, 1896, p. 704. X Proc. Linn. Soc. N.S. Wales, xxi. (1896) pp. 261-8 (2 pis.). 156 SUMMARY OF CURRENT RESEARCHES RELATING TO Structure of Cyanophycese and Bacteria. * * * § — While agreeing with many of Biitsckli’s conclusions, especially with his pronouncement of the honeycomb structure of protoplasm and of the cell-wall, Herr H. Zukal dissents from his view as to the nature of the “ central body ” in the Cyanophycese and Bacteria, which he maintains to have no relation to the true nucleus in higher plants. He points out that the protoplasm has naturally a denser consistency in the smallest organisms. From his observations of the phenomena in Fungi, he has convinced himself that the nucleus has been gradually developed from microsomes by differen- tiation and specialisation. Oscillatoria rubescens.f — Prof. R. Chodat has studied in detail the structure of this rare organism, which appears occasionally (in warm sea- sons) on the surface of Lake Morat, in Switzerland, in such quantities as to impart a pink colour to the water. The protoplasm contains a number of corpuscles, similar to those which have been taken for sulphur in other Algae ; they are, however, vacuoles filled with a gas. The pig- ment is not in a state of solution, but is intimately associated with the protoplasm, filling up the vacuoles ; although nearly invisible under the Microscope, it can readily be detected by the spectroscope. It appears to be identical with Sorby’s cc pink phycocyanin,” and Chodat proposes for it the term myxojporphyrin. The vacuoles have a remarkably re- sistant membrane. 13. Schizomycetes. Effect of Rontgen Rays on Bacteria.^ — Hr. J. Wittlin exposed several kinds of pathogenic bacteria to the influence of the Rontgen rays for a full hour, and found, from bacteriological examination, that the action of these was nil. Exposure of the medium before inoculation to the rays was also without influence. Loose Combination of Oxygen in certain Bacteria.§ — Prof. W. Pfeffer remarks that, as a rule, plant-cells do not store up oxygen in a loose combination, so that the streaming of the protoplasm very soon ceases when oxygen is absent. The author has made the theoretically important discovery that there are both coloured and colourless bacteria which, after the manner of haemoglobin, are able to pick up a consider- able quantity of oxygen, retaining it, however, in loose combination ; and that they are able to gradually give up this oxygen when they are confined in places devoid of it. Bacterium termo was used as a test of the presence of oxygen. B. termo was placed in a hanging drop in a gas chamber, on the floor of which the organism to be examined was put. Hydrogen was then passed through until B. termo stopped moving. When the organism gave off oxygen, B. termo began to move again. It was found that oxygen could be given off for twelve hours. The presence of C02 and the volume of oxygen were also determined in the course of these experiments. From the fact that these ^bacteria, even when dead, will form a combination with oxygen, it would seem possible that the * Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 331-9. Cf. this Journal, 1896, p. 662. f Journ. de Bot. (Morot), x. (1896) pp. 341-9, 405-9 (1 pi. and 1 fig.). " % Centralbl. f. Bakteriol. u. Parasitenk., 2te Abt., ii. (1896) pp. 676-7. § K. Sachs. Gesell. Wiss. Leipzig, July 1896, 5 pp. See Centralbl. f. Bakteriol. u. Parasitenk., 2te Abt , ii. (1896) pp. 763-4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 157 effective substance may be chemically isolated; and this view is sup- ported by tbe fact that a cold alcoholic extract combines with oxygen in a remarkable manner. Fossil Bacteria.* — M. B. Renault, in an exhaustive memoir dealing' with fossil bacteria, claims to have proved that Bacteriaceae are coeval with the first living organisms. The coccoid form appears to have been more frequent than the bacillar, and the cocci to be divisible into small and large. The action of both kinds of cocci is essentially destructive ; for in most cases disorganisation of structure is associated with their presence. According to this, it would seem to follow that coal contain- ing skeletons of organised structures is not the result of a complete microbic fermentation, while amorphous coal may be so. As certain bacilli, B. Tieghemi, B. vorax, B, gramma , and others are found only where there is evidence of considerable decomposition, the inference is that they appear after microbic fermentation has been set up by cocci. The cocci and bacilli found in fossil bone, teeth, scales, and coprolites have much the same size and appearance as those described by Yignal, Miller, and others in caries of bone and teeth. Certain bacilli, such as B. ozodeus , and B. gramma , are constantly found inside the sporanges of ferns, attacking first the spores and later the spore-cases. The destructive action of bacilli seems also to be great, and the reason why so much has been preserved is apparently the presence of ulmic acid in con- siderable quantity. In regard to coal formation, the presence of a coccus of a very dark colour, measuring 0 * 4 fi, is mentioned, but it is not affirmed that there are specific coal-forming bacteria. Before cell- destruction is complete, the bacteria often assume the zoogloea form ; and under these conditions spheroliths are formed. In the space at our disposal it would be difficult to impart an adequate notion of the author’s researches in the little known field of fossil bacteriology, but it is obvious that there is a future before it. The numerous illustrations are extremely effective. Bacterial Disease of Solanacese.f — Mr. E. F. Smith finds several species of Solanacese — the potato, tomato, and egg-plant, Solarium melon - gena , attacked by a disease which he calls “ brown-rot,” due to an unde- scribed parasite, Bacillus Solanacearum , resembling B. tracheiphilus and that known as “ Kramer’s bacillus,” but differing in several characters. Bacteriosis of the Hemp.J — Dr. Y. Peglion describes a disease which attacks the stem of the hemp, and which, though always accom- panied by a number of mould-fungi, he believes to be primarily due to the attacts of a Schizomycete. This organism, which is of the nature of a bacillus imbedded in mucilage, closely resembles B. cubonianus, a parasite of the mulberry, and may possibly be identical with it. Influence of the Cerium and Zirconium Groups on the Growth of Bacteria.§ — Dr. G. P. Drossbach states that the salts of cerium, didymium, lanthanum, yttrium, erbium, thorium, and zirconium have * Ann. Sci. Nat. (Bot.), ii. (189G) pp. 275-349 (46 figs.). Cf. this Journal, 1S96, p. 555. f U.S. Department Agriculture, Div. Yeg. Phys., Bull. No. 12, 1896, 26 pp. and 2 pis. % Malpighia, x. (f896) pp. 556-60. § Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xxi. (1897) pp. 57-8. 158 SUMMARY OF CURRENT RESEARCHES RELATING TO a marked inhibitory and preventive action on the growth and deve- lopment of bacteria, and suggests that these substances will possibly be used as antiseptics. Fixation of Free Nitrogen by Bacilli of Root-Tubercles.* — M. Maze made some experiments which show that when the bacilli of the root- tubercles of Leguminosae are placed in a suitable medium and under con- ditions which correspond as nearly as possible to those in the tubercles, they develop in quite a surprising way, and fix free nitrogen from the air. Hence the fixation of nitrogen belongs to the bacillus alone, and it is no longer necessary to explain this fixation by means of symbiosis. The cultivation media were solid surface cultures, composed of an infusion of haricots blancs, saccharose, gelose, with some sodium chloride and bicarbonate. The medium was placed in thin layers in fermentation flasks, and air supplied by aspiration. The air was purified from nitrogen in combination by passing it over heated copper shavings and sulphate of copper, and the moisture restored by causing the air stream to bubble through water. The inoculation was made by means of a spraying pipette, so that the surface of the medium was uniformly covered with germs. In another series the medium was devoid of gelose, but the results obtained were the same, that is to say, the weight of nitrogen at the end of the experiment was greater than at the beginning. It was, therefore, proved that the bacilli of the root-tubercles of Leguminosae have the power of fixing the free nitrogen of the air. Adaptability of Bacillus radicicola to Foreign Nutritive Media, j — Herren A. Stutzer, R. Burri and R. Maul made experiments with Bacillus radicicola for the purpose of ascertaining whether it could adapt itself to an unaccustomed environment. After obtaining pure cultures from strong and healthy lucerne plants grown in a medium made from lucerne, grape-sugar, and gelatin, the cultures were sown on a medium the basis of which was white mustard. It was found that, after several transferences on this latter medium, B. radicicola lost its vitality. Success was, however, attained by gradually accustoming the microbe to the mustard medium, and this was done by starting with a lucerne medium containing 5 per cent, of mustard medium, the propor- tion being gradually increased until B. radicicola grew well on the pure mustard medium. The success of these experiments shows that B. radici- cola possesses a high degree of adaptibility to unaccustomed nutritive conditions. Bacteriology of Mumps. if — Messrs. P. M. Mecray and J. J. Walsh j examined the secretion from the parotid and the blood in some cases of mumps. A coccus resembling that described by Laveran and Catrin, occurring in pairs chieliy, but also in fours and in larger groups, and about the same size as the ordinary suppuration cocci, was isolated. The colonies are circular white shiny points, with slow growth and gradual liquefaction of the gelatin. On potato the growth resembles at first thin white streaks, gradually extending to form a thin film. On * Ann. Inst. Pasteur, xi. (1897) pp. 44-54. t Centralbl. f. Bakteriol. u. Parasitenk., 2te Abt., ii. (1896) pp. 665-9. X Med. Record, Sept. 26, 1896. See Centralbl. f. Bakteriol. u. Parasitenk., l*e Abt., xxi. (1897) p. 68. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 159 blood-serum the growth is more rapid, but the colour of the colonies less white. Litmus milk turns red on the third day and coagulates. Milk is an excellent medium. Of eight cultures made from blood, two were negative; three gave pure cultures of the diplococcus; while the remain- ing three contained other cocci, notably a Staphylococcus , probably St. epidermidis albus. Non-Microbic Toxins.* — From an elaborate series of experiments made for the purpose of ascertaining the mechanism of immunity, M. A. Calmette and M. A. Delarde draw conclusions which may be summarised as follows : — The serum of animals naturally refractory to the toxins used (abrin and venin) rarely possesses antitoxic properties against these toxins. It may be remembered that the same phenomenon has been observed with regard to microbic toxins (tetanus). When the serum is antitoxic, as in the case of the hedgehog and mongoose, to serpent venom, the antitoxic power is but slightly marked, and bears no relation to the degree of immunity. Hence there is no correlation between the naturally refractory condition possessed by certain animals, and the antitoxic powers of their juices with regard to the toxins to which they are in- sensible. While warm-blooded refractory animals are able to form antitoxins under the influence of repeated injections of non-fatal doses of toxin, cold-blooded refractory animals are unable to do so. Cold- blooded refractory animals may acquire immunity to fatal doses of toxin without their serum becoming antitoxic. Antitoxic non-microbic serums may be practically employed for imparting passive immunity to man and animals against abrin and venin, and for the diagnosis of toxins in toxicological inquiries. The active substance of antitoxic serums is not altered by certain chemical reagents which destroy or profoundly alter the toxins ; when mixed in vitro with toxins the latter are unaf- fected. It seems to exist normally and abundantly in the protoplasm of leucocytes of vaccinated animals, whence it becomes diffused in the blood- serum and other organic fluids. It does not dialyse, and it has an energetic action on the leucocytes of fresh animals. Certain other substances devoid of specific action against toxins, such as meat-broth, normal serum, &c., appear to be able to impart preventive properties when injected into fresh animals. The authors further generalise their results and conclusions by pointing out that the antitoxic function is independent of immunity, as the latter may exist in the absence of the former, and that the two kinds of immunity, natural and acquired, are derived from a special property of the cells. The action of the toxins on the cells is compared to that of a magnet on a bar of soft iron. Ubiquity of the Typhoid Fever Bacillus.f — MM. P. Eemlinger and G. Schneider have made a series of observations which tend to show that the bacillus of typhoid fever has a universal distribution, that it exists in the soil, in water, and in the intestinal canal of persons unaffected with typhoid fever. Their remarks are preceded by an enumeration of the test characters of Eberth’s bacillus ; of these, eleven well-known and generally accepted criteria are merely mentioned, while two more are discussed at some length. These are the difficulty which the typhoid * Ann. Inst. Pasteur, x. (1896) pp. 675-707. f Op. cit., xi. (1897) pp. 55-66. 160 SUMMARY OF CURRENT RESEARCHES RELATING TO bacillus experiences in developing in a cultivation medium previously used for typhoid cultures, and the mode of action of the serum of immunised animals ; that is to say, the agglutinative action on cultures and the preventive action against infection. Out of 37 samples of water of various sources, 9 contained bacilli presenting all the characters of typhoid bacilli. In soils of different origin, 7 samples out of 13 showed typhoid bacilli. In five out of ten persons unaffected with typhoid, the stools contained bacilli identical with Eberth’s bacillus. Independent of the foregoing, bacilli were frequently met with, which while they presented the greatest resemblance to the typhoid bacillus, were distinguished therefrom by the absence of pathogenic properties and their indifference to typhoid serum. These organisms, the authors believe, are not only closely related to, but are possibly identical with, the Bacillus typhosus. According to the view laid down, typhoid fever is the result of depressing circumstances, which lead to a lowered vitality of the body. This depression allows the typhoid germs to assume the offensive, and overcome the resistance of the tissues of the body. Homology of Streptococci.* — Dr. C. Zenoni records some observa- tions on a Streptococcus obtained from the peritoneal exudation of a man suffering from peritonitis and orchitis. The coccus was of large size, and formed chains. It stained with Gram, and had the cultural appearance of Streptococcus . In different cultivation media the size varied consider- ably, as also did the length of the chains. The effect of virulent cultures was neutralised by means of Marmorek’s anti-streptococcous serum. The author regards his results as supporting the doctrine of the homology ot Streptococci. Tonsillitis caused by Friedlander’s Bacillus.-)- — MM. Ch. Nicolle and A. Hebert record the fact that they have met with eight cases of membranous tonsillitis caused by Friedlander’s bacillus ; six times in a state of purity, and twice associated with the diphtheria bacillus. The bacilli isolated Trom these membranes were examined as to their morpho- logical, cultural, and fermentative characteristics ; their virulence was also tested, and attempts made to reproduce a membrane in animals. Presence of Pneumobacillus of Friedlander in Water.J— According to M. L. Grimbert, the bacillus described by Mori under the name of B. capsulatus is identical with B. pneumoniee Friedlander. B. capsulatus was isolated from water in which, the author points out, the pneumo- bacillus of Friedlander may be frequently met with, and there in conjunc- tion with B. coli. These two species have frequently been confounded, from a general similarity of appearance, and a not too critical examina- tion. Neither stains by Gram’s method, nor liquefies gelatin ; both fer- ment lactose ; Friedlander’s bacillus is devoid of movement, and does not form indol. The author shows that these two organisms, B. coli and pneumobacillus, may be distinguished, first by the pneumobacillus never producing indol in a pep ton solution, and secondly, by its ability to fer- ment glycerin. On the other hand, B. coli does produce indol, and does not attack glycerin. The bacillus of Friedlander is easily isolated from * Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xxi. (3897) pp. 10-19 (3 figs.). t Ann. Inst. Pasteur, xi. (1897) pp. 67-79. t Op. cit. (1896) pp. 708-15. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 161 water by Pere’s method, in which procedure carbolic acid is added to the bouillon. Micrococcus cyanogenus.* — Messrs. L. H. Pammel and R. Combs obtained Micrococcus cyanogenus from a culture of B. aromaticus in milk. Within three or four days, the milk assumed a blue colour. M. cyano- genus is a small aerobic coccus which liquefies gelatin. The growth on agar is white, with faint blue colour. The blue colour imparted to milk disappears later on, and the milk is coagulated. In twenty-five days the coagulated milk is liquefied. No colour was developed on Dunham’s pep ton. Termobacterium Aceti.f — Herr A. Zeidler describes a bacterium Termobacterium aceti, the first prominent characteristic of which is its power to convert alcohol into acetic acid. Morphologically and cul- turally it resembles the Termobacteria as described by Cohn, except that it has a great tendency to produce involution forms. Its vitality is less than that of most acetifying bacteria, and it does not appear to have any particularly harmful qualities as far as brewing is concerned. * Proc. Iowa Acad. Sci., iii. pp. 135-40. See Centralbl. f. Bakteriol. u. Para sitenk., 2te Abt., ii. (1896) pp. 764-5. f Centralbl. f. Bakteriol. u. Parnsitenk., 2te Abt., ii. (1896) pp. 729-39. 1897 M 162 SUMMARY OF CURRENT RESEARCHES RELATING TO MICROSCOPY. a. Instruments, Accessories, &c.* Cl) Stands. ' Stands and various Equipments .f — Attention may be called to an editorial article in which recommendable stands are described from the catalogues of Zeiss, Schieck, Leitz, and others. General remarks are made concerning apertures, eye-pieces, magnifying power, apochromatic lenses, focusing arrangements, and the methods of using Abbe’s aperto- meter and test-plate. (2) Eye-pieces and Objectives. Apertures of Objectives.^ — Mr. R. B. L. Rawlings describes a simple method for roughly comparing the apertures of objectives, to be used when the Abbe apertometer is not available. As in the Abbe instrument, § a 3 in. auxiliary objective is attached to the under part of the draw-tube ; but in place of the bevelled semicircular glass plate, a sub-stage condenser and an iris diaphragm are used. The objective to be examined is first focused on the upper surface of the condenser, and then, without disturbing this adjustment, the auxiliary objective is screwed to the draw-tube, which is slid into such a posi- tion that the diaphragm is clearly seen ; when the margin of the dia- phragm is brought to the edge of the field of view, the diameter of the opening is in direct ratio to the aperture of the objective. Examining another objective in the same way, the apertures of the two are propor- tional to the diameters of the diaphragm openings in the two cases. It is suggested that a direct reading of the aperture could be made by combining the iris diaphragm with a graduated arc and index pointer ; this would give a measure of the diameter of the opening, and so a measure of the aperture of the objective. ' £3) Illuminating and other Apparatus. Monochromatic Light Apparatus.il — Mr. A. E. Tutton describes an instrument of precision for producing monochromatic light of any de- sired wave-length, and explains its use in the investigation of the optical properties of crystals. It consists essentially of a spectroscope, with one large 60° prism, in which the eye-piece of the telescope is replaced by a fixed slit. Light of different colours is caused to pass through this slit by rotating the dispersing apparatus, the position of which can be read off on the graduated circle, and this, after the instru- ment has been empirically graduated, will give an indication of the * This subdivision contains (1) Stands ; (2) Eye-pieces and Objectives ; (3) Illu- minating and other Apparatus ; (4) Photomicrography ; (5) Microscopical Optics and Manipulation ; (6) Miscellaneous. t Zeitschr. f. ang. Mikr., ii. (1897) pp. 321-35 (2 figs.). % Amer. Mon. Micr. Jourm, xviii. (1897) pp. 3-6 ; and English Mechanic, lxv. (1897) pp. 57-8. § This Journal, 1878, p. 19; 1880, p. 20; 1896, p. 247. || Phil. Trans., clxxxv. (1894) A, pp. 913-41 ; and Zeits. f. Krystal]., xxiv. (1895) pp. 455-74 (7 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 163 wave-length of the light passing through the slit. The light, after being diffused by a plate of finely ground glass, passes directly into the observing instrument — axial angle apparatus, goniometer or Micro- scope, &c. As a strong light is necessary, a lime-light lantern is used. Lens-Support, with Polarising Apparatus.* — Dr. C. Leiss describes an instrument for examining large mineral, rock and paleontological sections in polarised light, which is also useful for examining crystal groups, separating minerals, &c. ; it is made by Fuess after the designs of E. Kalkowsky. To the foot are hinged an illuminating mirror Sp, and a glass plate P, which acts as the polariser. The glass plate O, Fig. 8. which may be replaced by metal plates having suitable openings, carries the object. The lens can be moved about in a horizontal plane by means of an arm jointed at and s, and the rack and pinion T gives an extended range of vertical motion. The analysing nicol, a Glan- Thompson prism, fits over the lens, and a slot is provided for inserting a mica or gypsum plate. Two Steinlieil lenses, giving a large flat field and magnifying four and eight times, are supplied with the instrument. Thermostat heated by Mineral Oil for Paraffin Imbedding.f — Herr W. Karawaiew describes a thermostat devised by him, which is heated by petroleum or benzoline, and regulated automatically by elec- trical contact. When the temperature for which the apparatus is adjusted ascends above the desired degree, the mercury column of an air thermo- meter inserted in the interior of the thermostat rises until it comes into contact with a platinum point, thereby making a current which acts on an electro-magnet. The power of the magnet is exerted on a movable metallic plate, which is inserted between the source of heat and the bottom of the thermostat. In this way direct heating is prevented until, * Neues Jalirb. Mineral., i. (1897) pp. 81-2; and Zeitschr. ang. Mikr., ii. (1897) pp. 289-90. f Zeitschr. f. 'wise. ?T’kr., xiii. (1896) pp. 289-99 (3 figs.). M 2 161 SUMMARY OF CURRENT RESEARCHES RELATING TO by the sinking of the thermometer, contact is again dissolved. The apparatus is of small size (about 17 cm. square) and made of copper. It is stated not to vary more than J° during the 12 hours. (4) Photomicrography. On a Simple Method of Photomicrography by an Inexpensive Apparatus.* — Except for bodies of inappreciable thickness, photomicro- graphy will never be able to compete with accurate drawings made by the aid of the camera lucida. As the finger plays on the focusing-screw the eye is capable of fixing its attention on the portions of the image in sharp focus to the exclusion of those that are outside the focal plane, but no mere optical instrument is capable of doing this, and the result is that, where a body is of any thickness, the distinctness of the photographic image of the plane actually in focus is blurred, and marred by the hazy images of planes outside or within that plane. Something of the same kind is seen in ordinary landscape photo- graphy when lenses of long focus are employed ; either the foreground is blurred and the background sharp, or vice versa. Now, as the eye is accustomed to at once focus each object, whether near or distant, as it plays over a landscape, and cannot do this as it glances over the photo- graph, the result is unsatisfactory and unnatural. For this reason an enlargement from a view taken with a short focus lens, albeit it has special faults of its own, is often more satisfactory. If this be so patent in the ordinary photography of opaque objects, how much more unsatisfactory will be the result when, owing to the trans- parency of the objects, images of different degrees of sharpness are not merely juxta- but super-posed. Nevertheless, although for most ob- jects photomicrographs can never equal good drawings, especially for purposes of demonstration, the method presents great advantages on account of its facility and quickness, and is of special value in meeting the objections of that pestilential person, the sceptical negative observer. The man who, because he can find no free “ plasmodia ” in cases of Indian fever, refuses to believe that Laveran ever saw such bodies in Algeria, will be more convinced by a single photomicrograph than by a whole atlas of drawings. These latter may, or may not, be representations of the numerous fallacious appearances with which one becomes quickly familiar after working for a while at the examination of blood under high magnifica- tions ; but as a photograph must be a correct representation of some one aspect of the body, i.e. of the combination of the images of planes in and out of focus, its identity or otherwise with any known fallacy can be established in a way which is quite out of the question in the case of drawings. To be really useful, a photomicrographic apparatus should be so simple that it can be applied at once to the delineation of any object that may chance to be in the field of the Microscope ; and the difficulty of attaining this lies in the fact that ordinary illumination, such as is * By G. M. Giles, M.B., F.R.C.S., F.R.M.S., Surgeon I.M.S. Read February 17th, 1897. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 165 most convenient for ordinary observation, is far too feeble to be visible on the focusing-screen of the camera. In the early days of the art, when gelatin-bromide plates were yet unknown, direct sunlight was the only practicable illumination for anything but the most moderate amplifi- cations. To secure this a heliostat was indispensable, and it is now more than twenty years ago since the writer described in the Monthly Journal of this Society a plan in which this necessity was overcome, by em- ploying a condenser of such long focus that the image of the sun was vivid enough to give one time to insert one’s dark slide and expose before it had passed across the object. The wet collodion-plate, if not used quickly, was utterly spoiled. With the dry plate, on the other hand, apart from its greater sensitive- ness, length of exposure is a matter of no moment. The difficulty, how- ever, of obtaining adequate light to sufficiently illuminate the ground glass remains, and the method I am about to describe overcomes this by doing away with the focusing-screen altogether. No special camera is required. Almost any quarter-plate or 5 X 4-in. landscape camera will serve for the purpose ; but it is most convenient to select one with a conical bellows, in which the front is completely detachable from the standards that attach it to the base-frame when set up for ordinary work. The one I am using is an Adam’s “Victor” camera. The movable front carrying the lens is only 2 in. square, and a spare one, to receive the collar that is to connect camera and Micro- scope, is of course necessary. Take a piece of black velvet about 2 in. wide, and have it sewn round the draw-tube of the Microscope, not too tightly. Then take a long strip of brown paper 1 in. wide dipped in paste or gum, and wind it round the middle of the velvet till it is about 1/16 in. thick. When this has dried thoroughly, fold down the projecting part of the velvet over the outside of the pasteboard tube we have thus made, and sew the edges together so as to neatly cover the outside of the tube. Nothing more is required but to cut a hole in the spare front just large enough to tightly hold the velvet-covered pasteboard tube. If the hole be made the right size, the joint will be quite light-tight without any packing or cement of any sort. The Microscope is always used in the vertical position, and the camera is supported above it by means of a telescopic upright jointed vertically into a heavy base-board on which the Microscope stands. The base-board should be about 1 ft. square, and at least an inch thick, standing on four low studs placed at the corners, or, better still, with studs at three corners, and the fourth stud replaced by a coarse- pitched, blunt-ended screw, so as to allow for inequalities of the surface on which it may be placed, as it is important that the apparatus be as little liable to vibration as may be. The upright consists of two stout drawn metal tubes, sliding one within the other, of such lengths that the inner tube can be fixed, by means of a clam ping- screw, at any length between 15 and 20 in. The inner or sliding tube ends in a square metal plate about 2J in. square, with a central hole large enough to take the screw which ordinarily fixes the camera to its tripod. This plate must project a little clear of the surface of the tube, so that the base-board 166 SUMMARY OF CURRENT RESEARCHES RELATING TO of flie camera may clear the outer tube when it is being lowered. The upright is fixed nearly in the middle of the base-board, and the inner or sliding tube should be graduated to inches and tenths or millimetres, as may be preferred. Any good Microscope-stand will serve, but it is essential that the fine-adjustment should have a graduated head, and a revolving stage is a great convenience. The above dimensions are calculated for the largest but one of Zeiss’ stands. I have not a catalogue by me, but it is, I believe, deno- Fig. 9. Camera attached to Microscope. minated IIa. In this stand the milled head of the fine-adjustment is divided into 50 parts, marked from 2 to 100. If the Microscope which it is desired to use be not provided with a graduated fine-adjustment, a special one must be fitted, which can easily be done by turning up a flat button of hard wood, with a cavity below just large enough to slip tightly over the milled head, and with the upper surface flat, on which can be gummed a paper disc graduated to 2° or 4°, as may be convenient. The provision of an index carried on some part of the arm of the ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 167 Microscope will not greatly tax ingenuity, but its position will neces- sarily vary with the type of Microscope employed. When it is desired to use the apparatus, it is placed in front of an open* window, and the Microscope is placed on the base-hoard at such a distance from the vertical pillar that the axis of the camera, when placed in position, may coincide with that of the Microscope. Having found this position, make a pencil outline of the foot of the Microscope on the Fig. 10. Camera swung aside to admit of adjustment of light, focusing, &c. base-board, so that it can be, in future, removed and replaced without further trouble. The camera is now screwed on to the plate of the upright, and adjusted so that its focusing-screen is accurately parallel with the base-board and the stage of the Microscope ; but it is not, at this stage of the proceedings, placed over the Microscope, but turned aside out of the way, by twisting the inner tube of the standard within the outer one, 168 SUMMARY OF CURRENT RESEARCHES RELATING TO so that one is able to examine an object under the Microscope as easily as if it were standing on the table, quite clear of any photographic attachment. The pasteboard tube carrying the camera front is, however, fitted on to the draw-tube, as, owing to its sm^ll size, it does not interfere with the use of the Microscope any more than a micrometer eye-piece or other ocular attachment. The easiest way to indicate the principles of the method I wish to advocate, will be to describe the method in a specific case. Say it is desired to obtain a photograph of an object under Zeiss’ C with oc. 3, the draw-tube at its full length. The object is placed in position, accurately focused, and lighted to the best advantage by means of the concave mirror. If great exactitude be desired, exact parallelism may be secured by levelling the stage of the Microscope and the focusing-screen with a spirit-level. The camera, with the bellows hanging loose and unattached, is now swung round, so that it is suspended over the Microscope, and fixed at such a height that the length from the eye-piece to the focusing-screen may be about 8 in. Its front frame is now gently fitted on to the movable front already attached to the Microscope. If the ground glass be now examined under a focusing-cloth it will be found that there is too little light on the plate to enable one even to see the position of the object, far less whether or no it is in focus ; but, as a matter of fact, it will be nearly so — though, in all probability, the error, combined with the difference between actinic and visual foci, will necessitate the lens being focused a little away from the object to obtain a sharp picture. Suppose now we focus the lens out four-hundredths, i.e. two divisions of the Zeiss milled head, and, having inserted an Ilford ordinary plate in the camera, proceed to expose for about one minute. On develojnng the plate, if the lenses used at all correspond to those I am using, a very fairly sharp picture will result. Now examine the plate closely for any portion of the picture that may be in sharp focus, and, having noted this, detach the camera front and swing the camera out of the way, and note exactly the number of divisions through which the milled head must revolve to bring this into sharp visual focus as one looks through the Microscope. A few experiments may be necessary before this correction is accu- rately obtained; but, once it has been ascertained for any given combination of objective, ocular, and length of camera, sharply focused photographs may be obtained with far greater certainty than in the ordinary way, because it is far easier to focus sharply an object observed in the ordinary manner through the Microscope, than when the image is dulled by being examined through a ground-glass surface. The weaker the objective, the larger will he the correction necessary ; for instance, with draw-tube fully out, oc. 3, and a camera-length of 8 in., I find that I have for objective A to focus out 25 mm., for B 10 mm., for C 4 mm., and for D 2 * 5 mm. The exposure, of course, must be increased as the square of tho linear amplification or, given that one minute suffice for C, about 3 ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 169 minutes will be required if D be substituted for it, which magnifies not quite twice as much. B, on the other hand, will require but 15 seconds, and A only 4 or 5. The length of exposure will, of course, vary greatly with the quality of the light obtainable, but, as long as one has sufficient to see the object for ordinary purposes of microscopic observation, it is merely a question of so many minutes or seconds exposure more or less, and it is as easy to get a good photograph in an English November as in the brightest day of summer. The correction necessary for each combination requires, of course, a few careful experiments ; but this effected, is done once for always ; and, as each experiment helps greatly towards the next combination, one soon obtains a table of corrections for all the combinations one is likely to require. The photomicrographic expert will doubtless object that it is better to dispense with the eye-piece,* and employ the image given by the objective directly ; but though this may be so in the case of difficult objects, such as diatoms under high amplification, it necessitates the use of a camera of unwieldy length, and is, moreover, an almost hopeless task, unless the tube of the Microscope be done away with altogether, and the objective be made to screw directly on to the camera-front ; for, however carefully the tube may be blacked, the reflection from its sides produces an unbearable glare in the centre of the plate, and, in the case of a Microscope in regular use, the portion in contact with the eye-piece becomes so polished, that little else but central glare is visible on a negative given by the objective alone. For the purposes, there- fore, of the working biologist, it is far better to use the eye-piece, in spite of the small theoretical disadvantages of the plan. If the camera-length beyond the eye-piece be about 8 in., the scale of the resulting negative will be somewhere about the nominal mag- nifying-power of the combination in the case of Continental outfits. English opticians, however, calculate their amplifications at 10 in. from the eye-piece ; so that, in the case of English Microscopes, the amplification will be a good deal less than the nominal power of the combination. I cannot, however, recommend working with any greater extension, as very few lenses will bear the test. The plates used should be the slowest obtainable. The more rapid the plate, the coarser is the grain of the film, and therefore the less suited it is for our purpose. In this respect, gelatin plates compare ill with the old wet collodion, the grain of which was so fine that a sheet of the c Times ’ reduced to a square about half an inch square could still be easily read under a sufficiently powerful lens. Collodion emulsions are, however, coming a great deal into use once more for a variety of purposes ; and, though slow, would be doubtless to be preferred for photomicrographical wrork. A waiter in the current c Photographic Almanac ’ praises highly the Hill-Norris collodion-plate (medium speed) for photomicrography ; but * [The general practice of the best photomicrographers in this country is to use an eye-piece.] 170 SUMMARY OF CURRENT RESEARCHES RELATING TO as I can find no reference to these plates in the advertisement-sheets of the Almanac, I have not been able to put them to practical trial. To shut off the light preparatory to exposing, I employ simply a piece of black velvet gummed on to a visiting card, slipped on top of the ring that carries the Abbe condenser ; but it would be undoubtedly better to use a flap-shutter working inside the camera just behind the eye-piece ; as under all but the highest powers the object is more or less visible as an opaque object, after the light has been cut off from below ; and though the amount of light so thrown is too small to have much effect during the short time that elapses between drawing the shutter of the dark slide and exposing, it must have a certain more or less fogging effect, and should therefore be avoided by those who have sufficient micro work to set aside a camera specially for the purpose. As will be seen, the apparatus described need cost but little. Simple as it is, it may be further simplified by using a simple wooden upright, mortised into the base-board, to carry the camera. One misses the great convenience of being able to instantly swing the camera out of the way when changing objects and focusing ; but, apart from the delay involved in having to unscrew and replace the camera on such occasions, such an appliance is quite as efficient as that first described, aud reduces the cost of the appliance required to connect one’s camera and Microscope to a few pence. Many biologists are unhandy with their pencils, and, looking upon “ micro ” work as a particularly recondite branch of photography, are debarred from employing this means of illustrating their observations. If a few such can be induced to discover how simple a matter photo- graphic recording can be made, I believe the space I have occupied in the Journal will not be wasted. Photomicrographs.* — Dr. J. Eismond discusses the pros and cons in regard to photomicrographs. He suggests a compromise between them and drawings. A faint copy of the negative is taken on platinum paper or the like ; and this is touched up with ink, pencil, or colours, so as to differentiate any particular structure. A Simple Arrangement for taking Slightly Enlarged Stereoscopic Photographs.-]- — Dr. W. Gebhart points out that with an ordinary stereoscopic camera, in which the two objectives are fixed at only a small distance apart, the object cannot be brought close enough to the camera to produce an enlarged picture ; this could be done by using two cameras having their axes converging to the object, or by moving one camera into two positions about a vertical axis passing through the object. In the majority of cases (except, for example, with a polished sphere) the same result would be obtained if the camera remained fixed and the object be turned through a small angle. For this purpose the object is placed at the centre of a wooden disc, which can be turned about a vertical axis, through the required angle, this angle, of 6-15°, depending on the distance of the camera, being indicated by graduations on the disc and an index-pointer. * Eiol. Centralbl., xvi. (189(5) pp. 864-5. f Zeitschr. f. wiss. Mikr., xiii. (1896) pp. 419-23 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. J 71 £. Technique.* (1) Collecting- Objects, including Culture Processus. Practical Method for Preparing Agar for Cultivation Purposes.! — 100 grm. of agar are first washed with cold water and then placed in a kettle containing 50 litres of boiling water and 200 grm. of Carraghen powder previously rubbed up with cold water. The boiling is continued until all the agar is dissolved, after which it is allowed to cool down to 50°, when ten whole hen’s eggs, previously well beaten up, are added. The fluid is boiled for a further 5—10 minutes and then strained through linen. One per cent, of glycerin is added to the agar mass, which, after distribution into five litre flasks, is sterilised. When required for use a flask is liquefied in a steamer and the hot fluid poured through a thick layer of cotton-wool. The filtrate after subsequent sterilisation should be clear. If, however, the glass vessel be of inferior quality it may render the medium turbid owing to giving up alkali. On this medium, even without addition of pepton and nutritive substances, most fission and yeast fungi will grow. Cultivation of Diphtheria Bacilli on Non- Albuminous Media.! — Herr N. Uschinsky states that he has succeeded in obtaining cultiva- tions of diphtheria in his medium. § The toxin therefrom was copious and strong, 1 • 5 ccm. of a 4-6 weeks old culture killing a guinea-pig in 36-40 hours. The previous non-success was due to not recognising that young cultures are unsuitable, while old ones grow easily in non- albuminous media. The appearance of the cultures in Uschinsky’s fluid resembles those in bouillon. The filtrate gives a distinct albu- minous reaction, though, of course, it does not follow that this is due to the toxin. Culture of Saprolegniace8e.|| — Dr. A. Maurizio recommends pollen- grains (of a great variety of plants) as a favourable medium for the cultivation of Fungi belonging to the genera Adilya and Sajprolegnia. Growth of Diphtheria Bacilli in Milk.lf — Prof. M. Schottelius shows that for diphtheria bacilli raw warm cow’s milk is an extremely favour- able growth-medium, as compared with sterilised milk or alkaline bouillon. The figures, which speak for themselves, are, at room temperature, raw milk 21, sterilised milk 2, bouillon 7 ; at incubation temperature, raw milk 50, sterilised milk 6, bouillon 18. Keeping Potatoes for Culture Purposes.** — Dr.W. Simmonds states that potatoes may be kept for quite a long time without getting mouldy or dry by the following method, which he has practised for a year and * This subdivision contains (1) Collecting Objects, including Culture Pro- cesses; (2) Preparing Objects; (3) Cutting, including Imbedding and Microtomes; (4) Staining and Injecting ; (5) Mounting, including slides, preservative fluids, &c. ; (6) Miscellaneous. t Marpmann’s Bakt. Chem. Laborat. in Leipzig*; Zeitschr. f. ang. Mikr., ii. (1896) p. 237. X Centralbl. f. Bakteriol. u. Parasitenk., xxi. (1897) pp. 146-7. § See this Journal, 1893, p. 796. (| Arch. Sci. Phys. et Nat., ci. (1896) pp. 599-601. Cf. this Journal, 1896, p. 446. 1" Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 897-900. ** Op. cit., xxi. (1897) p. 100-1. 172 SUMMARY OF CURRENT RESEARCHES RELATING TO a half. After having been cleaned and boiled in the usual way, the potatoes are, when cold, bound round with twine and suspended close together. They are then immersed in shellac solution thrice at intervals of half an hour. In the course of another hour they are quite dry, and may be stored away for future use. Examining Rectal Mucus for Tubercle Bacilli.* — According to Dr. Sawyer, it is useful for diagnostic purposes to examine the mucus from the rectum if there be no sputum, or if tubercle bacilli cannot be demonstrated in the pulmonary excreta. The author quotes three cases in which he found tubercle bacilli in considerable numbers in the rectal mucus, but none elsewhere. Simple Method for the Sero-Diagnosis of Enteric Fever.f — Prof. E. Pfuhl takes a drop of blood from the ear and mixes it in the hollow of a slide with ten times the quantity of water. This not only dilutes the blood, but gets rid of the red corpuscles. To the serum is then added an equal quantity of a bouillon culture of typhoid bacilli. This is done by dabbing the culture on a cover-glass and inverting it over the serum in the ground- out slide. Improvement in the Sedgwick-Rafter Method for the Microsco- pical Examination of Drinking Water 4 — The Sedgwick-Rafter method, now extensively employed in America for the analysis of drinking waters, is, says Mr. D. D. Jackson, as follows : — A definite quantity of water, usually 250 ccm., is filtered through Berkshire sand placed in a funnel. The size of the grains is such that while they will pass through a sieve of 60 meshes to the inch, they will not through one having 120 to the inch. The organisms adhere to the sand, while the water passes through a hole at the bottom of the funnel closed by fine bolting cloth. The sand is dropped into a test-tube containing 5 ccm. of sterile water. The tube is then shaken and the water decanted with another test-tube. The micro- organisms are distributed by blowing into the water with a pipette, and 1 ccm. removed to a cell 50 mm. long by 20 mm. wide and 1 mm. deep. The Microscope is graduated so that each field examines one cubic millimetre of water. The improvement made by the author consists in altering the shape of the funnel, which has a diameter of 2 in., and a length to the beginning of the slope of 9 in. The length of the slope is 3 in. The leg of the funnel is 2J in. long, and its internal diameter 1/2 in. The lower end is closed by a rubber plug, perforated by a small hole, and the latter covered with fine bolting cloth. Above the plug is a layer of fine sand about 3/4 in. thick. The most important errors to which this method is liable, says Mr. G. 0. W hippie, § arise from the concentration of the sample. These are (1) the funnel error, or that caused by the adhesion of the organisms to the sides of the funnel ; (2) the sand error, or that caused by the organ- isms passing through the sand ; (3) the decantation error, or that caused by the organisms adhering to the particles of sand, and by the water used in washing the sand being held back by capillarity during decan- * Med. News, May 23, 1896. See Centralbl. f. Bakteriol. u. Parasitenk., lte Alt., xxi. (1897) p. 71. t Centralbl. f. Bakteriol. u. Parasitenk., xxi. (1897) pp. 52-7. t Teclinol. Quarterly, ix. (1896) pp. 271-4 (1 ph). § Tom. cit., pp. 275-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 173 tation. The decantation error is minimised by the shape of the funnel devised by Mr. Jackson. The amount of sand error depends on the character of the organisms, upon the size of the sand-grains, and the depth of the sand. The decantation error chiefly depends on manipu- lation, and arises from some of the organisms remaining attached to the sand-grains. C2) Preparing- Objects. Isolation of the Elements of the Crystalline Lens * — Dr. W. Geb- hardt places the eyeball in a 4 to 10 per cent, solution of formalin for one or two days. All the transparent parts retain their transparency, and the vitreous its muco-gelatinous consistence. The bulb, which may be preserved in the formalin solution, is then transferred to 50-60 per cent, alcohol for a couple of hours. The lens is then taken up and gently squeezed between two fingers. By slight pressure it is broken up into separate lamellae, which can be easily teased out in water or glycerin. Both the toothed and smooth fibres are easily isolated, the teeth being extremely clear. The preparation may be stained, and mounted in glycerin-gelatin. Method of Preparing Rotifers.j — M. N. de Zograf has a note on this subject, in which he states that, after trying Mr. C. F. Rousselet’s method of preserving rotifers, he found that formalin preserved the animals for a very short time only. To this it must be remarked that, while M. de Zograf’s experience cannot have extended for more than twelve months, in this country the rotifers mounted by Mr. Rousselet in formalin for the last three years have kept extremely well, and look at present as if they were going to keep a great number of years more. The only difficulty experienced has been to prevent the evaporation of the watery fluid, which has now apparently been overcome by using thickened gold size and Bell’s cement for sealing the slides. M. de Zograf mentions a method by which he has succeeded in mounting rotifers in balsam. After narcotisation with cocain, killing, and fixing with *25 per cent, osmic acid, a rather large quantity of a weak (10 per cent.) solution of raw wood vinegar is added, and the ani- mals left therein from five to ten minutes ; they are then washed in three changes of distilled water, which is gradually replaced by alcohol of progressive strengths, finishing with absolute alcohol. In this way the rotifers do not shrink, and can be passed into glycerin or Canada balsam in the usual way. The protoplasm and organs are coloured by this method a bluish-grey or deep black, but the histological structure is well shown. (3) Cutting, including Imbedding and Microtomes. New Microtomes by Fromme.J — Prof- J- Schaffer described two new microtomes, made by Fromme Brothers, of Vienna, for cutting large sections : — 1. For Paraffin-Imbeddings. — The object is carried at the side of a rectangular frame, which is fixed to a horizontal axis working in bearings * Zeitschr. f. wiss. Mikr., xiii. (1896) pp. 306-7. t Comptes Rendus, cxxiv. (1897) pp. 245-6. % Zeitschr. f. wiss. Mikr., xiii. (1896) pp. 1-9 (3 figs.). 174 SUMMARY OF CURRENT RESEARCHES RELATING TO in the heavy foot of the instrument ; the knife is fixed to the foot in a vertical position. The small side-movement of the object is effected by a micrometer screw and toothed wheel carried within the rectangular frame. 2. For Celloidin-Imbeddings and for Cutting in Liquids. — Here the knife is carried horizontally on a rectangular frame, which, in this in- strument, works about a vertical axis ; the object is fixed to the foot of the instrument, and the small movement is given to the knife by the micrometer arrangement within the rectangular frame. For cutting in liquids, a small bath is arranged round the object-holder, and the knife is carried on an arm bent twice at right angles and projecting over the edge of the bath. Manipulation of Celloidin Sections.*— By the following procedure, devised by Dr. G. Aubertin, the chief inconveniences inherent in the ceiloidin-section may be avoided. The sections, cut in 70 per cent, alcohol, are arranged on the slide. The celloidin is then dehydrated, first in 70 per cent., and finally in absolute alcohol. When perfectly de- hydrated, the celloidin is dissolved by dropping on very carefully a mix- ture of ether and alcohol in equal parts, with which the whole surface of the slide should be just covered. The ether-alcohol mixture may be re- newed until the whole slide is covered with a very thin layer of celloidin. The ether-alcohol is allowed to evaporate, but not to complete dryness of the celloidin. The membrane thus formed is not only firm, but so delicate that staining is easily effected. The after-treatment sug- gested is — 70 per cent, alcohol, water (20 minutes), dilute solution of borax-carmine (some hours), water (10 minutes), haematoxylin (10 minutes), hydrochloric acid-alcohol until the celloidin is decolorised. The pre- parations should be dehydrated in 95 per cent, spirit, cleared up in xylol-carbolic acid (3-1), and mounted in balsam. (4) Staining- and Injecting. Investigation of Brain of Fishes.f — M. Catois has made use of a process which he describes as a combination of the injection-methods of Ehrlich and Meyer with the immersion-method of Dogiel, and the diffu- sion-process of Cajal. Into the living animal there were injected 1 to 2 ccm. of concentrated salt solution of methylen-blue ; on the brain being removed, sections were made of it, and the pieces placed for about half an hour in a saturated solution of methylen-blue, after which they were treated in the ordinary way. Preparation of Embryonic Nervous System of Crustacea.! — M. N. de Zograf has made use of Prof. Ramon y Cajal’s method of double impregnation ; he reports that he had many difficulties to overcome before succeeding with the larvae of Copepoda. He could not cover the Nauplius with a layer of glycerin and gelatin to .preserve it from the silver precipitate, as is often done with minute objects, for this reagent dehydrates the larvae, and makes it impossible to recognise their struc- * Anat. Anzeig., xiii. (1897) pp. 90-3. f Comptes Rendus, cxxiv. (1897) pp. 204-5. J Tom. cit., p. 202. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 175 ture. He succeeded, however, by enveloping the Nauplii in pieces of cigarette paper. Rapid Method of Fixing and Staining Blood-Films.* — Dr. G. L. Gulland fixes and stains blood-films in the following way : — The covers are dropped film-side downwards into the fixative, which is composed of absolute alcohol saturated with eosin 25 ccm., ether 25 ccm., sublimate in absolute alcohol (2 grm. to 10 ccm.) 5 drops. After an immersion of three or four minutes, the covers are removed with forceps and washed in water. The film is then stained for just one minute in a saturated aqueous solution of methylen-blue, after which it is washed in water, dehydrated in absolute alcohol, and mounted. Modification of Heller’s Method of Staining Medullated Nerve- Fibres.f — Dr. W. F. Robertson first treats healthy or morbid nervous tissue with Weigert’s chrome-alum-copper fluid for ten days or longer. The fluid is composed of 2 • 5 per cent, chrome-alum, 5 per cent, copper acetate, 5 per cent, acetic acid, and formalin 2 per cent. The chrome-alum is boiled in the required amount of water, and when dissolved the acetic acid and copper acetate are put in. When cold the solution is filtered and the formalin then added. The author has reduced the quantity from 10 to 2 per cent., as too much formalin impairs the staining reaction. Sections of material may be obtained by the celloidin or gum-freezing method, and they are stained by placing them in 1 per cent, osmic acid for half an hour in the dark, then in 5 per cent, pyrogallic acid for half an hour, 0 * 25 per cent, potassium permanganate for 3-4 minutes, 1 per cent, oxalic acid for 3-5 minutes. Wash in water after treatment with each solution, dehydrate, then mount in balsam. Staining Coccidium oviforme.J — Dr. R. Abel stains Coccidium ovi- forme with the Ziehl-Neelsen solution for tubercle bacilli. The parasites may be stained on cover-glasses, or in sections. After staining with hot phenol-fuchsin, the preparations are to be decolorised in 5 per cent, sulphuric acid and 70 per cent, alcohol. Any contrast stain may be used. Method for Staining Unnucleated Cells.§— Herr J. J. Gerassimotf states that if a Sjpirogyra cell be treated with chloroform, ether, or with chloral hydrate during fission, two daughter-cells will be obtained, one being devoid of nuclear substance, the other containing excess thereof, i.e. there is one large nucleus or two of ordinary size ; in fact, the results are exactly the same as those induced by the action of a low temperature. To 100 ccm. of the water containing the algas were added 0 • 25—1 • 5 ccm, of saturated chloral hydrate solution, or 0-42-2*5 ccm. of ether, or 1 • 25-7 -5 ccm. chloroform water. The time required varied from fifteen minutes to some hours, after which the algte were removed to fresh water. New Method of Staining Tubercle Bacilli. ||— Drs. A. Rondelli and L. Buscalioni propose the following method for staining tubercle bacilli, which they say is extremely rapid and simple : — The decoloriser is a * Brit. Med. Journ., 1897, i. p. 652. f Tom. cit., pp. 651-2. % Centralbl. f. Bakteriol. u. Parasitenk., lte Abt., xx. (1896) pp. 904-5. § Moscow, 1896, 4 pp. 11 See Centralbl. f. Bakteriol. u. Parasitenk , lte Abt., xxi. (1897) pp. 70-1. 176 SUMMARY OF CURRENT RESEARCHES RELATING TO modified eau de Javelle, made by mixing two solutions. The first is composed of calcium hypochlorite 6 grm. in 60 grm. of water. The second is composed of 12 grm. of potassium carbonate dissolved in 40 grm. of water, and after filtration is mixed witb the first solution. The combination is stirred up for some time, then filtered and preserved in blue glass bottles. After the film has been prepared and stained in the] usual way, the cover-glass is immersed in the Javelle decoloriser until it looks brownish-yellow. Decoloration of Celloidin in Orcein Preparations.* — It is very difficult, says Prof. P. Schiefferdecker, to decolorise the celloidin when celloidin-sections are stained with orcein to show the elastic fibres. This inconvenience may be avoided by transferring the preparations, after they have been decolorised in hydrochloric acid alcohol, to water containing some liq. ammon. caustici. In this the sections become blue and give up some pigment. As soon as the dye ceases to be given off, the preparations are put back into the hydrochloric acid alcohol. The process is to be repeated until the celloidin is sufficiently decolorised. Staining Centrosomes.j — Dr. R. Marchesini recommends, for a study of centrosomes and attraction-spheres in the leucocytes of the newt, a thorough mixture of 1 part of malachite-green solution to 2 parts of saifran in-green. (5) Mounting-, including- Slides, Preservative Fluids, &c. Marking Preparations.^— Prof. P. Schiefferdecker advises that slides should be permanently marked in black or white by writing on the glass and then varnishing the surface. The liquid Chinese ink does well for the black, while Eremser white or permanent Chinese white is recom- mended for white. The Eremser white should be rubbed up with a sufficient quantity of gum-water. When the writing is dry it should be brushed over with water-colour varnish. Herr E. Schoebel § points out that the method proposed by Schiefferdecker of writing on glass with Indian ink and then varnishing over, is much the same as that used for many years at the Zoological Station of Naples; here, however, the writing is done over the varnish. Schiefferdecker’ s objections to the author’s method || of writing on glass , with a mixture of sodium silicate and fluid Indian ink are answered. (6) Miscellaneous. Plate Modelling.! — Dr. A. Schaper, in preparing his models, uses Born’s ** method, but takes special precautions for properly orientating the object, so that sections are made in known and definite directions. The details of the method, as applied to embryos, are described at length. * Zeitsclir. f. wiss. Mikr., xiii. (1896) p. 302. t Boll. Soc. Rom. Stud. Zool., v. (1896) pp. 89-96 (1 pi.). % Zeitsclir. f. wiss. Mikr., xiii. (1896) pp. 299-301. § Tom cit., pp. 425-8. || Op. cit., xi. (1894) p. 331. Cf. tliis Journal, 1895, p. 707. ! Zeitschr. f. wiss. Mikr., xiii. (1897) pp. 446-59 (10 figs.). ** This Journal, 1889, p. 144. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 177 Tests for Ligneous Tissue.* — Dr. F. Zctzsche enumerates twenty- eight different methods which have been used and recommended by vari- ous experimentalists for the detection of woody tissue. Out of these the following eight are commended: — (1) indol with hydrochloric acid; (2) phloroglucin-hydrochloric acid ; (3) carbazol-sulphuric acid ; (4) anilin sulphate ; (5) toluidin-diamin-hydrochloric acid ; (6) ammoniacal fuchsin; (7) Bismarck-brown-lisematoxylin ; (8) solid-green deltapurpurin. The best results are obtained from the following : — (1) The indol- hydrochloric reaction gives a brick-red to chocolate-brown colour ; may be used successfully in from 1/100 to 1/1000 per cent, solution; and has the great merit of allowing the objects to be mounted in glycerin and in balsam. (2) Phloroglucin is used in 2—3 per cent, alcoholic solution, together wTith an equal volume of dilute hydrochloric acid. The colour is brownish -red. Preparations do not mount well in either glycerin or balsam. (3) A mixture of equal volumes of alcoholic solu- tion of Bismarck-brown and Bohmert’s hasmatoxylin has the special merit of not requiring differentiation, but care must be taken not to overstain. Lignification is shown by the brown staining, the non-ligneous tissue being blue. The preparations should be mounted in glycerin- gelatin. (4) The ammoniacal fuchsin solution is made by freely diluting a saturated alcoholic solution of fuchsin with water, and then adding ammonia until the fuchsin just begins to precipitate. The objects are immersed therein for 1/2 minute, and, after having been well washed, are contrast-stained in saturated anilin-blue solution (1 minute). After dehydration in alcohol they are mounted in balsam. The intensity of lignification is determinable by the use of solutions of phloroglucin-hydrochloric acid, of varying strengths, allowed to act for a definite time. Three minutes is suggested as the time limit, and 1/40 to 2 percent, for the solution. The latter is made by dissolving the phloroglucin in 1 vol. of 90 per cent, alcohol and 1 vol. of strong hydrochloric acid. The phloroglucin is first dissolved in the alcohol, and the acid afterwards added very gradually in the cold. Eight degrees tf lignification are made by the author from this method, at the top of the list standing Abies pectinata , at the bottom, Musa paradisiaca. Demonstrating Presence of Agar.j — According to Herr G. Marp- mann, there are many edible alga3 in tropical seas. These belong to the group of Floridem, with red, lcaf-like or membranous growth and upright thallus. Among these are Gracilaria lichenoides Ag., Eucheuma spinosum and E. gelatmse Ag. All these, when boiled with water, pro- duce a thick jelly, which in the dried condition is known as agar-agar. This agar appears to be chemically identical with the alga-mucus of Gclidium corneum. The agar jelly and Gelidium jelly, dissolved in boiling water, filtered through cotton-wool and precipitated with alcohol, form horny masses when dried, the former being known as gelose, the latter as gelinose. As pectin, or vegetable jelly, appears to be of the same, or very nearly the same chemical composition as agar, and as fruit jelly is often adulterated with agar and gelatin, it becomes important to have a ready test to distinguish the presence of agar. This may be done micro- * Zeitsclir. f. ang. Milcr., ii. (189C) pp. 225-3G. f Tom. cit., pp. 257-G1. 1897 N 178 SUMMARY OF CURRENT RESEARCHES. scopically owing to the presence of the siliceous envelopes of the algae having resisted destruction. The mass to be examined should be treated with dilute sulphuric acid and a few crystals of permanganate of potash. In this way a thin fluid is formed which is easily sedimented, the sili- ceous envelopes of the algae being found in the deposit. Disinfection of Books.* — Dr. von Schab records some experiments made for the purpose of testing the value of Pict.etys gas-mixture and formaldehyd for disinfecting books from lending libraries. Pictetrs mixture consists of equal volumes of sulphurous acid and carbonic acid gases. The test objects used were Bacillus pyocyaneus, B. anthracis , Staphylococcus pyogenes aureus, and tubercular sputum. Neither disinfectant gave satisfactory results. Demonstration of Small Quantities of Formaldehyd.f — According to Herr L. Keutmann, a solution of hydrochlorate of morphia in strong sulphuric acid is very convenient for showing the presence of formal- dehyd. One decigram of morphia hydrochlorate is dissolved in 1 cem. of strong sulphuric acid. This solution will detect the presence of 1 part of formaldehyd in 5000 or 6000 parts. The solution to be tested is poured upon (but not mixed with) the morphia solution, and within a few minutes assumes a red-violet hue. * Centralbl. f. Bakteriol. u. Farasitenk., xxi. (1897) pp. 141-6. f Zeitschr. f. ang. Mikr., ii. (1896) p. 267. 179 PROCEEDINGS OF THE SOCIETY. MEETING Held on the 17th of February, 1897, at 20 Hanover Square, W., The President (E. M. Nelson, Esq.) in the Chair. The Minutes of the Anniversary Meeting held 20fch of January last were read and confirmed, and were signed by the President. The Secretary said he regretted that the February number of the Journal was not ready for issue to the Fellows that evening. The delay was due to the impossibility of getting the plates as early as necessary, but he believed these would be delivered at once, so that the Journal would probably be ready for delivery by the following Monday. The List of Donations to the Society (exclusive of exchanges and reprints) received since the last meeting was read, and the thanks of the Society were given to the donors. From A Slide-carrier for the Lantern The President. Dr. E. B. Wilson, The Cell in Development and Inheritance. (Svo, New York, 18U6) The Publishers. The President said that on the occasion of Mr. Michael’s very able address to the Society at their last meeting, be could hardly help having his attention attracted to the slide-carrier, and the unsatisfactory way in which it worked in the lantern, and he had therefore much pleasure in presenting to the Society a new carrier, which he hoped would be found to work more smoothly and with less trouble to the operator. Prof. Bell said he should like to call attention to a book included in the list of donations, for which the Society was indebted to Messrs. Macmillan, ‘ The Cell in Development and Inheritance,5 by Dr. E. B. Wilson. This was the fourth volume of a very interesting series of biological works now being issued by the Columbia University. It was exceedingly interesting and important to have a compendious account of all that was known at present about the cell ; but though of great value now, at the rate at which researches were being made in these subjects, it was quite 180 PROCEEDINGS OF THE SOCIETY. possible that, ten years hence, the information given in this book might be regarded as too antiquated to be of farther service. The President said that Mr. Curties had sent for exhibition a nose- piece which had been devised for rapidly attaching an objective to obviate some of the disadvantages in the older form of a similar con- trivance where the attachment was made by a pinion, which might happen to be in some inconvenient position. The new form was made with a ring, which was much more easy to work. The article described was exhibited to the meeting, and the method of its application practically demonstrated. The thinks of the meeting were given to Mr. Curties for sending, and to the President for exhibiting and explaining, this useful piece of apparatus. The President said they had received a paper, ‘On a Simple Method of Photomicrography,’ from Dr. G. M. Giles, who was at present in India. Having read the principal portions of the paper to the meeting, the President further remarked that it would be seen that the author described what he might call a contrivance for rough-and-ready work. In India they would not be likely to have at hand any of the appliances we had, and Dr. Giles in his paper had described how he had managed without them. His remarks as to low-angled lenses would, no doubt, bo the portion of the paper most likely to be criticised by those who were practically acquainted with the subject, and his use of these would no doubt largely accouut for the unfavourable comparisons made between jihotographs and drawings; for he thought it would be admitted by all who knew anything about the subject, that if photomicrographs were taken properly, no drawing could at all compare with them for accurate scientific work. Where, however, the best modern apparatus was not available, one had, of course, to make use of what was ready to hand, and that described in this paper was a cheap way of making a “ rough- and-ready ” vertical photomicrographic apparatus The thanks of the meeting were unanimously voted to Dr. Giles for his communication, and to the President for reading it to the meeting. The following Instruments, Objects, &c., were exhibited:— * Mr. E. M. Nelson: — Mr. Baker’s Changing Nose-Piece. Mr. J. E. Ingpen Tegmen of Flala sp. Natal, showing chordotonal papillae? New Fellows. — The following gentlemen were balloted for and duly elected Ordinary Fellows : — Mr. Jonathan Pollard and Dr. Siegfried Czapski. PR CEEDINGS OF THE SOCIETY. 181 MEETING Held on tfte 17tii of March, 1897, at 20 Hanover Square, W. E. M. Nelson, Esq, President, in the Chair. The Minutes of tlie meeting of 17th February last were read and confirmed, and were signed by the President. The List of Donations to the Society since the last meeting was read, and the thanks of the meeting were given to the donors. A. C. Cole, The Methods of Microscopical Research. (8vo, London, 1895) Mr. W. D. Colver. An old Microscope Mr. Jas. More, jun. The Secretary gave notice, on behalf of the Council, that the next meeting, which would be held on Wednesday, April 21st, would be made special for the purpose of making alterations in Bye-laws Nos. 10 aud 20. Rule 20 read at present as follows : — “ Every ordinary Fellow of the Society shall pay an admission fee of two guineas, and a further sum of two guineas as an annual subscription.” It was now proposed to alter this so far as the first portion, relating to the admission fee, was con- cerned, by inserting after the words “ admission fee of two guineas ” the words “ or at his option an annual sum of 10s. for a period of five years in lieu thereof.” This would necessitate an alteration in Rule 10 also, and it was proposed to insert after the words “ shall pay the admission fee ” the words “ or the first instalment thereof as provided by Rule 20.” The Secretary said that it appeared there was not a copy of the second edition of Mr. A. C. Cole’s c Methods of Microscopical Research ’ in the Society’s Library, and Mr. Colver had kindly supplied the want by presenting them with a copy. The President said that Mr. More, who had some time since pre- sented them with an old Microscope for the Society’s museum, had just sent them another, with a letter asking him to present it to the Society on his behalf. This instrument, which he exhibited to the meeting, was a very perfect example of the old Culpeper and Scarlet type, but it was evidently not so old as the one which Mr. More formerly presented to them, because this one had a rack work focusing arrangement which was not found in the earlier types. It had the usual box stand with drawer and accessories, and was in very good condition. He felt sure the Society would be very pleased to possess what was a very handsome model of this old form of Microscope, examples of which were becoming rather scarce just now. The Secretary said there had for some time been a vacancy on their list of Honorary Members, consequent upon the death of Prof. Pasteur. 182 PROCEEDINGS OF THE SOCIETY. It was now proposed to fill this by the election of Dr. G. B. do Toni, and he gave notice on behalf of the Council that the ballot for this purpose would be taken at the next ordinary meeting. The President said he wished to exhibit a lens which he had com- puted, of the loup type, giving a magnifying power of ten, but con- structed upon an entirely new formula. The working distance, as compared with Zeiss’s, was 60 per cent, greater, being no less than 8/10 in. He also exhibited a new achromatic aud aplanatic bull’s-eye condenser for use with the Microscope. He thought it was likely to be very useful to those who were doing any special work in photomicrography, or wherever a really achromatic parallel beam was required. Prof. A. E. Wright brought forward a method of measuring and counting microscopic objects. He was uncertain whether the method was a new one, but he had not seen it described, and he thought that the method was one which compared favourably with the micrometric methods which were described in the text-books, and which were ordinarily in use. The method consisted in projecting, by means of the substage condenser, a minified image of a scale or of a system of squares upon the plane upon which the microscopic objects were disposed. By means of diagrams which were drawn upon the blackboard, it was explained that the scale or the system of squares could be placed in any one of the three following positions : — (a) On a glass plate (or on the window), which was interposed between the source of light and the plane mirror; (6) on the surface of the plane mirror; or (c) on a plate interposed between the plane mirror and the substage condenser. Under any of these circumstances it was shown that the image of the scale could, by proper focusing of the condenser, be superposed upon the microscopic object. It was suggested that this method of projecting a system of squares upon the microscopic preparation might be employed with advantage in the enumeration of red blood-corpuscles. The employment of this method would obviate the necessity for the micrometric ruling on the bottom of the haemocytometer cell. It was further shown that the proposed method of mensuration pre- sented advantages over the methods of mensuration which are at present in use, inasmuch as the value of the divisions of the scale did not vary with the magnification which was applied, but was a constant so long as no change was made in the relative positions of the Microscope and the scale. The value of the divisions of the scale could thus be deter- mined once for all for a particular Microscope, comparing them with the divisions of a stage micrometer. It was further explained — first, that the same scale, if set up at different distances from the Microscope, could be made to give either large or small micrometric divisions ; and secondly, that the foreshorten- ing of the interspaces between the horizontal divisions could readily be corrected for by disposing the glass plate upon which the scale was inscribed in a plane exactly parallel to the plane of the mirror. PROCEEDINGS OF THE SOCIETY. 183 It was shown that this correction for foreshortening was essential in cases where a system of squares is to be projected upon the microscopic specimen ; and further, that it can be made in a very simple manner by suspending the ruled glass plate in such a manner as to allow its upper margin to tilt forward until an equal number of vertical and horizontal squares appear in the field of the Microscope. These points were illustrated by setting up a Microscope in such a manner as to show the image of a system of squares superposed upon a film of blood. Prof. Wright also called attention to a Microscope made by Messrs. Swift, in which a very simple plan had been adopted of swinging the substage condenser in and out of the optical axis. Dr. J. L. Williams read a paper ‘ On the Formation and Structure of Dental Enamel,’ the subject being illustrated by a large number of photomicrographs of mounted sections shown upon the screen, some of these showing an amplification of x 3000. Mr. J. Howard Mummery said he felt sure that all the Members present who did any work in photomicrography would appreciate the great beauty of the slides shown by Dr. Williams, especially when they recognised the extreme difficulty of photographing the microscopic structure of enamel. It had always been a matter of some difficulty to understand how the growing enamel was nourished during the earlier part of its development, the blood-vessels being then separated from the stratum intermedium and ameloblasts by the stellate reticulum ; but if, as Dr. Williams suggested, the meshes of the stellate reticulum are occupied at this time by large cells, the matter was explained. In the photograph shown it was rather curious to notice that all the nuclei of these cells seemed to be at the intersections and not in the middle of the cell ; but this might be only an accidental result of the preparation of the speci- men. In the later stages of enamel development the slides showed very distinctly the presence of an abundant blood supply in the stratum intermedium, and he certainly considered that Dr. Williams’ communi- cation demonstrated these points in the development of enamel very clearly, and he looked upon it as the most valuable contribution to the study of the development and structure of enamel that had been made for many years. The President said he could most heartily concur in the opinion expressed by Mr. Mummery as to the great excellence of the slides which had been exhibited, and all would agree with him as to the very lucid way in which the subject had been presented. He had great pleasure, therefore, in moving a very hearty vote of thanks to Dr. Williams for his communication, and for one of the most beautiful lantern exhibitions that they had seen for some time. The vote of thanks was put to the meeting, and carried by acclama- tion. PROCEEDINGS OF THE SOCIETY. 184 The following Instruments, Objects, &e., were exhibited:— Prof. A. E. Wright : — Method of Measuring and Counting Micro- scopic Object^, illustrating his paper ; An easy Method of Moving the Substage Condenser into and out of the optical axis. The President: — An Achromatic Loup multiplying 10; an Achro- matic and Aplanatic Bull’s-eye; an old Microscope, presented to the Society by Mr. James More, jun. New Fellows: — Mr. George Peter Dincen and Mr. John Blakeway Wolstenholme. UUl 2 1897 JOURNAL OF TI1E ROYAL MICROSCOPICAL SOCIETY. JUNE 1897. TRANSACTIONS OF THE SOCIETY. Y. — On a New Mechanical Stage. By Edward M. Nelson, President R.M.S. {Bead 2Ut April, 1897.) I have the honour to bring before the Society an improved mecha- nical stage which Messrs. Watson and Sons have made from my drawings. The improvement consists in converting my semi-mechanical horse-shoe stage, figs. 11, 12, and 13 (exhibited here in February 1893 *) into a completely mechanical movement.! This has been carried out in the following manner. The sliding bar has been slotted, fig. 14, and a movable piece, which may be called the shuttle, has been fitted in the slot ; this shuttle has diagonal rack-work at the back, and a vertical spiral pinion gears in it, fig. 15. Above this pinion there is a horizontal bevel-wheel, which is geared by friction to a vertical wheel fixed on the usual horizontal pinion. The cock which holds, and is close to, the ver- tical bevel wheel in fig. 15 is slotted underneath; a capstan-headed screw (not shown in the figure) is fitted for the purpose of compress- ing this spring part ; the amount of friction between the copper bevel wheels can therefore be regulated at will. This capstan-headed screw is placed some distance from the bearing, so that the length of the bar between it and the bearing may form a stiff spring ; this renders the motion equable. It will be noticed, therefore, that the transverse movement is confined to the sliding bar. This sliding bar can be removed so as to leave the stage perfectly plain. The heads of the pinions which control the vertical movement have been kept below the level of the stage, so as to be out of the way of culture-plates (fig. 12). In deference to the views expressed by Mr. Michael in his last * Journ. R.M.S., 1893, p. 236. f The 1893 stage was itself an improvement on a previous model I had designed and exhibited in 1888. All the main ideas in the plan of the 1888 stage are em- bodied in this new one, the alterations and improvements being in the mechanical details. See Journ. E.M.S., 1888, p. 477. 1897 0 186 Transactions of the Society . Presidential Address, -no less than 3J in. of transverse movement have been given to the stage. This will greatly facilitate the exami- Fig. 11. Fig. 13. nation of serial sections. The manner in which the slip is held is entirely novel : on the shuttle there are two sliding pieces, and these On a Neiv Mechanical Stage, By Edward M. Nelson. 187 hold the slip by the two lower comers, fig. 14. This method obvi- ates all gripping of the slip, and does not interfere with the feeling of the working distance by the finger. Slips from 2h in. to 4J in. can he taken. Fig. 14. The stage has been made of aluminium for lightness, and its size is 4J x 7 in. The stand has a spread of tripod of 8 x 8 in. The length of the body when closed, including the rotating nose-piece, is •5J, and when extended by means of the rack-work and sliding draw- Fig. 15. tubes is 11 J in. long, so that it will work equally well with objectives -corrected for either the long or short tube. The weight of the instru- ment is 7 lb. 10 oz. o 2 SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY (principally invertebrata and cryptogamia), MICROSCOPY, Etc. Including Original Communications from Fellows and Others* * * § ZOOLOGY. VERTEBRATA. a. Embryologry.f Artificial Insemination.* — Mr. W. Heape lias made experiments which, so far as they go, point to the conclusion that both copulation and the presence of spermatozoa in the uterus are necessary to induce ovulation in the virgin rabbit when she is in “ heat.” But this is not so in certain other mammals, such as mice and dogs, as the results of artificial insemination show. The author summarises the experiments of Spallanzani, P. Rossi, Sir Everett Millais, and others, besides noting some which he has himself made. “ It has been ascertained that if spermatozoa be placed artificially in the vagina of certain female mammals at the right season, they may conceive ; it has been ascer- tained also that if spermatozoa be placed artificially within the uterus of certain individual mammals which have failed for particular reasons to breed by natural means, they may become pregnant in consequence.” From one emission by a dog several bitches may be inseminated. “ There is little doubt that an extended study of the subject will throw light on the physiological relations of coition and insemination, ovulation and fertilisation, and on certain of the causes which induce sterility in mammals, which will be of great interest to physiologists and of great value to practical breeders.” The experiments should also- facilitate the study of hybridisation and telegony. Artificial Fertilisation of Rabbit’s Ova.§— Herr W. S. Grusdew has followed Spallanzani, Schenk (1878), and Ott (1882), in making * The Society are not intended to be denoted by the editorial “ we,” and they do not hold themselves responsible for the views of the authors of the papers noted,, nor for any claim to nOvelty or otherwise made by them. The object of this part of the Journal is to present a summary of the papers as actually published, and to describe and illustrate Instruments, Apparatus, &c., which are either new or have not been previously described in this country. f This section includes not only papers relating to Embryology properly so called, but also those dealing with Evolution, Development and Reproduction, and allied subjects. t Proc. Roy. Soc., lxi. (1897) pp. 52-63. § Arch. f. Anat. u. Entwicklgesch. (His u. Braune), 1896, pp. 269-304 (1 pl.)j. See Zcol. Centralbl., iv. (1897) pp. 217-9. SUMMARY OF CURRENT RESEARCHES. 189 experiments on artificial fertilisation. Ova and sperms were artificially placed in the oviduct ; but out of 88 cases only 28 were in tlie least suc- cessful. The susceptibility to fertilisation seems to depend on invisible changes in the vitellus and zona pellucida. Ova in which the ger- minal vesicle is still visible are not fertilisable. In no case was more than one polar body seen. The movement of the ova through the tubes takes 22-47 hours. As many as 20 spermatozoa may be found asso- ciated with one ovum. The actual penetration of the ovum by a sperma- tozoon was observed. An albuminoid sheath is formed around the ovum only when the rabbit is in heat or in natural pregnancy. Egg-laying* in Eana fusca.* — Prof. M. Nussbaum adds to a pre- viously reported communication a note to the effect that isolated females of Hana fusca produce spawn apart from the presence of males. Even with the presence of males the edible frogs do not spawn in captivity ; both sexes become sterile. Oogenesis in Annra.f — Herr J. F. Gemmil describes this in Pelo - ■bates. In the young ovary the primitive germ-cells lie superficially; genital strands grow inwards into the internal tissue and form a some- what sponge-like structure with wide meshes lined by genital epithelium ; the partitions disappear and a single cavity is formed. Thereupon the internal germ-cells form nests of cells by mitosis, and a struggle for existence occurs in these nests. Some of the cells form the granulosa or internal follicle cells, others disintegrate into nutritive material, usually only one forms an ovum. If there is abundant space, several ova occur in a nest. In the formation of the granulosa some indifferent cells of the genital epithelium also take part. The growing ova press towards the central cavity and protrude the genital epithelium before them as the external follicular envelope. Development of Liver and Pancreas.}: — Prof. J. A. Hammar says that the divergences in the early development of the liver cannot be spoken of as due to the presence of one primary duct or of two. “ Primary liver-ducts,” in the usual sense, occur only in birds. The common feature is not the development of a duct or of ducts, but the develop- ment of a liver-fold or “ liver-prominence ” caudal to the heart, and the constriction thereof into a duct running cranialwards. In Amphioxus the simplest condition persists throughout life. In other Vertebrates, the duct forms the ductus choledochus ; the cranial portion of the liver- fold forms the hepatic parenchyma ; a diverticulum of the ventral wall of the liver-fold forms the gall-bladder and its duct. The author then discusses the various forms of the hepatic parenchyma in Vertebrates. In another paper § Hammar denies that there is a double ventral rudiment of the pancreas in the rabbit, dog, &c. From its first emer- gence the rudiment is a single caudally directed diverticulum of the ductus choledochus. Development of Thyroid Gland in Man.|| — Herr J. J. Streiff finds that the thyroid begins as a branched tubular gland. But the tubules * Arch. f. Mikr. Anat., xlviii. (1897) pp. 545-50 (1 pi.). f Arch. f. Anat. u. Entwicklgesch . 1890, pp. 230-8 (2 pis.). See Zool. Centralbl., iv. (1897) p. 184. % Anat. Anzeig., xiii. (1897) pp. 233-47 (14 figs.). § Tom. eit., pp. 247-9 (2 figs.). j[ Arch. f. Mikr. Anat., xlviii. (1897) pp. 579-86 (1 pi.). 190 SUMMARY OF CURRENT RESEARCHES RELATING TO enlarge into vesicles, and are separated from one another by proliferating vessels and connective-tissue strands. Thus the secretory parts dis- charge their secretion separately. It passes by pressure through the walls of the follicles into the lymph spaces of the connective tissue. Prochorion of the Dog.* — Prof. R. Bonnet describes the blasto- dermic vesicle in the dog in its earlier stages, with special reference to the so-called “prochorion.” Until it exceeds 11 mm. in length the ovum lies surrounded by the oolemma (zona pellucida) — at first wholly, afterwards less completely — and by an external gelatinous sheath or “ prochorion ” of Hensen. On eggs immersed in water a large number of transparent threads are seen floating out from the gelatinous sheath. These are merely secretion-threads from the uterine glands, of which the prochorion is a product. Placenta of Weasel.f — Prof. H. Strahl concludes, from his study of the early attachment of the mammalian ovum to the wall of the uterus, that the syncytial formations occurring during this process arise from modifications of the uterine epithelium. Part of this is used in the formation of the placenta, and part is disintegrated into what may serve as nutritive material. The author has confirmed these conclusions by a study of the placenta of Putorius faro. Development of Selachii4 — Prof. C. K. Hoffmann begins by de- scribing the process of gastrulation and the rudiments of the two primary germinal layers. He finds a large gastrular invagination at the posterior end of the blastoderm of Acanthias. It is at first a more or less spherical vesicle, readily visible to the naked eye ; but the blastopore becomes a long narrow cleft, and the archenteric cavity extends forwards between the blastoderm and the yolk. The blastopore closes, and from its fused lips arises the embryonic rim which forms the first rudiment of the embryo. Many authors have mistaken the primitive archenteric cavity for the segmentation cavity. None have distinguished it as the primary gastrula cavity. But none of it passes into the embryo ; indeed, of the whole blastoderm only the embryonic rim is persistent. A “ secondary archenteron ” is subsequently formed. The yolk-sac represents the last vestige of the original or archi-gastrula. Prom the appearance of the segmentation-cavity on to the time when the embryo proper begins to develop, no mitotic divisions are demonstrable in the yolk-nuclei, though amitotic divisions occur; but after the establishment of the embryo begins there is an abundance of mitotic divisions in the yolk-nuclei, which certainly have a direct share in the development of the germinal layers and embryo. The bilateral mesoderm and the notochord arise from the embryonic rim ( TJrmund ) ; the gastral or axial mesoblast seems to arise as a paired outgrowth from the archenteric wall. The protovertebrse of the anterior head-region. In young stages the embryonic archenteron extends as a broad solid strand beneath that part of the brain which corresponds to the future thalamencephalon, and is continued on to the neuropore. This strand is soon divided into * Anat. Anzeig., xiii. (1897) pp. 161-70 (1 fig.). t Op. cit., xii. (1896) pp. 539-43. X Morpliol. Jalirb., xxiv. (1896) pp. 209-86 (4 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 191 a median and two lateral portions, which probably correspond to the portions which give rise further back to gut and notochord on the one hand, and to mesoblast plates on the other. The axial portion, beneath the thalamencephalon, degenerates ; the paired portions seem to form the foremost palingenetic pair of somites, or anterior head-cavities of Platt. What van Wijhe has reported as to the three foremost palingenetic head-somites in Scyllium and Pristiurus is confirmed by Hoffmann in regard to Acanthias. He promises a future discussion of the three posterior palingenetic and the four coenogenetic protovertebrae. Olfactory organ and nerves. Apart from the optic nerve, the olfactory diverges from all the other cranial nerves. As van Wijhe has shown, both the olfactory organ and its nerve arise from the anterior neuropore. Mouth and hypophysis. The hypophysis is formed very late, long after the oral opening. Development of Auditory Vesicle in Vertebrates.* — Dr. C. Poli has studied this in a variety of types. In Sauropsida, the first hint of the ear is a zone of thickened ectoderm alongside of the still open medullary groove. This zone proliferates and thickens, perhaps repre- senting a rudimentary somite. In relation to the segmentation of the medulla, the invagination occurs between the fourth and fifth neuro- meres. On the appearance of the gill-pouches the auditory zone extends ventrally by thickening of the branchial zone. The ventral and dorsal margins of the invagination fuse, and a vesicle is formed. The space occupied is at first the dorsal portion of the posterior half of the hyoid arch rudiment ; but when the vesicle is closed, the second branchial aperture corresponds to the boundary between the anterior two-thirds and the posterior third of the vesicle. The appearance of the auditory nerves is preceded by the development of a strand of spindle-shaped cells which forms the supporting tissue for the facial and auditory group. But these two nerves arise quite separately. The histogenesis of the auditory neuro-epithelium resembles in its earlier stages that of the me- dullary canal, supporting spongioblasts becoming distinct from the neuroblasts. In Selachians a thickened ectoderm-ridge appears in the earliest stages alongside of the medullary groove, and in this the auditory zone arises. Goronowitsch’s interpretation of the ganglion-ridgo in birds is corroborated in Selachians, — it gives off supporting elements to the peripheral nervous system. The first histogenetic changes in the audi- tory epithelium, which indicate the maculae acoustic®, begin earlier than in fowl-embryos. Two-thirds of the auditory vesicle lie in the posterior half of the hyoid arch region. After the vesicle has been formed there is still no appearance of lateral organs. In Anura there is no sensory-plate common to the three upper sense- orgaDs; what Goetto described as such is the ganglion-ridge. The invagination arises from an insinking of the lower layer of the ectoderm, and is thus from the first bounded in front by the superficial layer of the ectoderm. The vesicle is closed by a proliferation of the margins of the invagination. Before the vesicle is closed, the recessus labyrinth'i * Arch. f. Mikr. Anat., xlviii. (1897) pp. 6H-86 (2 pis.). SUMMARY OF CURRENT RESEARCHES RELATING TO ■102 is visible in rudiment. The space occupied is between tbe second and third of Goette’s segments. The author regards the ear as representing a segment, and finds its 'remote homologue in the cirrhi dorsales of Annelids. Fangs of the Adder.* * * § — Prof. L. Kathariner has made some interest- ing observations on the growth of the reserve teeth in the adder, especially in regard to the growth of the mucous membrane folds which brings the opening of the poison-duct into functional connection with each succes- sive fang. Anatomically the poison-duct always opens into the mouth, hut the sheath of mucous membrane around the base of the tooth secures practical, though never organic, continuity between the poison-duct and the canal of the tooth. Ten is the usual number of reserve fangs ; each seems to last about six weeks ; the separation of an old fang is effected by odontoclasts in the pulp-cavity. The tooth consists of cement, dentin, fibro-dentin, and an enarrel-cuticula, but there is no enamel. But the most important part of the paper is that which elucidates the establishment of the connection between a new fang and the poison-duct. Attraction-Spheres in Spermatogenesis.f — Dr. R. von Erlanger summarises and discusses some of the recent papers — by Niessing, Rawitz, Wilcox, and others — on the role of attraction -sphere and cen- trosome in spermatogenesis. He concludes that the centrodeutoplasm [= archoplasm] consists of a special substance which is not present in the centroplasm ( = attraction-sphere) of ova and of somatic cells. It collects around the centrosome when that has played its active part in cell-division, and it attains considerable dimensions only when the genital cells have passed through a long resting period. Thus there is ti marked contrast between the centrodeutoplasm and the centroplasm (van Beneden’s sphere), for the latter is formed de novo around each active centrosome in each division, unless, indeed, the divisions succeed one another very rapidly. Where a centrodeutoplasm occurs, it is dif- fused in the prophases of division by the fresh centroplasm ; it is scat- tered in the cytoplasm by the growing spindle ; it only collects again around the centrosome or centrosomes during the anaphases or telophases. Life-History of the Eel. if — Dr. C. G. J. Petersen regards the three so-called varieties of eel as representing three stages in development. The yellow eels comprise both males and females, but are all young fish, which have not yet commenced to assume the bridal dress of the adult, and in which the generative organs arc little developed. The frog-mouthed eels are larger females still in the same conditions ; while the silver eels comprise both males and females which have taken on the bridal dress, and are about to migrate to the sea to spawn. Prof. G. B. Grassi § has shown that Anguilla vulgaris , the common eel, matures in the depths of the sea and spawns there, that its eggs float, and that the young pass through a larval form known as Leplo - cephalus brevirosiris. * Zool. Jahrb., Abtii. Anat., x. (1897) pp. 55-92 (3 pis., 5 figs.). t Zool. Centralbl., iv. (1897) pp. 153-71. t Cited in Journ. Mar. Biol. Ass., iv. (1897) pp. 375-9, from ‘ Report of the Danish Biological Station to the Home Department,’ v. (1894). § Proc. Roy. Soc , lx. No. 363, Dec. 1896. Cf. Quart. Journ. Micr. Sci., xsxix. .{1897) part 3 ; and Journ. Mar. Biol. Soc., iii. (1896) pp. 278-87. ZOOLOGY AND BOTANY. MICROSCOPY, ETC. 193 Lines of Variation and Germinal Selection.* — Prof. C. Emery emphasises the importance of Weismann’s recent essay on Germinal Selection. A new departure may be due to germinal selection alone ; personal selection will not influence its origin ; there may be a conflict between germinal and personal selection, as when a strong new character exceeds the optimum. Emery does not agree with Weismann that all organic structure is adaptive ; many characters appear to him to be quite indifferent. Nor does he admit the necessity of assuming an un- failing supply of fit variations ; the extinction of races is eloquent proof of the reverse. He also points out that if an environmental change (e.g. of climate) influenced not only the body, but the determinants of the germ-plasm as well ; and if it influenced not a fraction of similar determinants (which might lead to germinal struggle between the changed and the unchanged), but influenced all alike ; and if the same factor operated for several generations ; and if the resulting change was indifferent, i.e. without selection-value ; then there is a logical possibility of the origin of a character without any selection. Organic Selection.! — Prof. J. Mark Baldwin uses this phrase, which can hardly be called self-explanatory, to express “ the perpetuation and development of congenital coincident variations in consequence of accom- modation.” By “ accommodation ” is here meant an adaptive reaction of the organism to its environment, which may result in a “ modifica- tion.” The idea is that congenital variations coincident or in the same line with adaptive modifications, are screened by the modifications, and thus indirectly selected. (Perhaps “ indirect selection ” might be sug- gested instead of “ organic selection.”) The results of organic selection are included under the term ortlioplasy, which has, however, a wider con- notation. Prof. Baldwin’s contribution contains other suggestions to- wards a more definite terminology. Study in Variation.^ — Mr. H. C. Bumpus has used X-rays in the investigation of the variations which occur in the vertebral column of Necturus maculatus Raf. A hundred specimens were examined. There is an average of 35 per cent, of liomoeotic variation, i.e. where a .vertebra, for instance, assumes a structure which is proper to another in a different ordinal position in the series. These variations are all in the pelvic region. There is also considerable meristic variation, i.e. in the total number of segments in the column. The two forms of variation are as- sociated; for specimens with abnormally placed sacra (homoeotic) present -a considerably increased meristic variation ; and extremes in meristic vertebral variation tend towards homoeosis. There is a ratio between the absolute length of the animal and the number of vertebras. Some suggestions are made to show that forward homoeosis is, so to speak, easier than backward homoeosis, which is less frequent. The author maintains that the differentiation of the sacral vertebra is the result of centripetal influence from the growing Anlage of the appen- dage, whose primitive position may readily vary a little, thus inducing an unsymmetrical sacrum. Pie argues that the appendage appears at a definite topographical point, without respect to the location of certain * Biol. Centralbl., xvii. (1897) pp. 142-6. f Nature, Iv. (1897) p. 558. t Journ. Morphol., xii. (1897) pp. 455-84 (8 pis.). 194 SUMMARY OF CURRENT RESEARCHES RELATING TO segments of the neighbouring axial area. Variations in the pectoral arch and in other parts of the skeleton are associated with the pelvio variations. The pelvic variations were commoner in the, females. In- tercalation, in the sense of the introduction of new segments, does not take place. Problems of Heredity.* — Herr G. Schlater has published a lecture on the problems of heredity. These, he says, must first be solved in the domain of the single cell, wherein, like many others, he finds an array of structural units or cytoblasts — five different kinds in the nucleus, three in the body of the cell. There are three large questions : — The structure of the hereditary substance; the individuality or specific nature of this in different organisms ; and the mechanism of transmission. In discussing Weismann’s position, the author notes the difficulty involved in the fact that the hereditary substance in the germ-cell is to that in the adult (in man) as 1 : 25,000,000,000. During this increase there is opportunity for change or specialisation under the influence of the “ chief factors of development.” The chief factors in ontogeny include (1) the sum of external condi- tions ; (2) the organisation of the living matter ; and (3) the conditions of co-ordination and co-operation dependent on these. The chief determinant of inheritance is to be found in the specific individuality of the cytoblasts of the germ-cells. Experiments on Supposed Inheritance of Acquired Characters.! — Dr. L. Hill tested Brown-Sequard’s conclusion that, after section of the cervical sympathetic nerve in guinea-pigs, a droop of the upper eyelid is acquired, and that this droop is transmitted. In March 1895, six normal guinea-pigs were operated on, a droop of the eyelid was established, and has persisted. They were allowed to interbreed, but in none of the young was a persistent droop of the eyelid observable. Further ex- periments have proved absolutely negative. The author suggests that the apparent transmission of a droop in Brown-Sequard’s cases may have been due to individually acquired conjunctivitis, which seems common enough in young guinea-pigs. Alleged Modification of Bird's Stomach.! — Dr. G. Brandes finds a mare’s nest in the reputed modification of the bird’s stomach as the result of altered diet. His own experiments on pigeons, gulls, &c., yielded quite negative results. Holmgren’s were much the same, showing at most a general degeneration in the muscularity of the gizzard in the pigeons which he fed on flesh. Sir Everard Home seems to be responsible for the familiar results usually attributed to Hunter, who seems to have said little on the matter, though he made a preparation showing unusually strong musculature in the stomach of a gull fed for a year on corn. The other records are equally unsatisfactory. The nature of the stomach is doubtless variable, but “ there is not the slightest evidence ” of a gizzard being modified into a soft stomach, or conversely. Brandes suggests scepticism as to some other cases of alleged direct modification. * Biol. Centralbl., xvi. (1896) pp. 689-94, 732-41. t Proc. Zool. Soc. London (1896, published 1897), part 4, pp. 785-6. I Biol. Centralbl., xvi. (1896) pp. 825-38 (7 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 195 Influence of Heat and Light on Pigmentation of Salamander Larvae.* — Professor W. Flemming finds that lighter pigmentation of salamander larvae may be induced ley increased temperature (Fischel), as well as by increased illumination (Flemming). The experiment was as follows : — I. (a) A number of larvae, in a cellar at 4°-5° C., in a white vessel in the window. Result in 8 days — light brownish colour. ( b ) In a grey, covered vessel, in same cellar in the dark. Result in 8 days — as dark as usual. II. (a) A number in a warm room (19°-20° C.), in a white vessel in the window. Result in 8 days — the lightest larvae. ( b ) In a brown, half-covered stoneware vessel, in the same room. Result in 8 days — light-brownish colour as in I (.a). Hypertrichosis. f — Prof. A. Brandt has written an interesting essay on so-called dog-men, or more technically on hypertrichosis universalis. We refer to it merely in respect of its aetiological interest. The abnormal hairiness is regarded by some, e.g. Yirchow, Bartels, and Waldeyer, as a post-embryonic growth ; it is regarded by others, e.g. Darwin, von Sie- bold, Ecker, Unna, as a persistence and exaggeration of the lanugo foetalis. Brandt’s view is that an inhibitory influence, weakening the integumentary system, results in a hypertrichosis lanuginosa foetalis , the primitive hairs remaining, like the antlers on a castrated stag. The same weakness which caused the retention of the primitive hair may also express itself in defective dentition. Brandt recognises, however, that another kind of hypertrichosis may result from an exaggerated formative activity in the skin. But the two states are quite distinct. Viragines.'j — Prof. A. Brandt discusses the aetiological significance of the beard in Yiragines, which some — e.g. Kennel — interpret as a re- version-phenomenon, which the author, on the other hand, regards as a prophetic variation, expressing a tendency on the female’s part to gain a characteristic which many males have long since acquired. Epidermis Folds on Palms and Soles of Primates.§ — Dr. H. H. Wilder concludes that the callous pads on the feet of walking pentadac- tylous mammals become reduced in certain monkeys to fleshy mounds without definite boundaries. Over these mounds the folds, which are elsewhere approximately parallel, are distorted (from this primitive pattern) into whorls, spirals, or loops. In some Primates, including man, the mounds are reduced, so that only the epidermic figure or centre is left, or even that may disappear. In man the apical centres on the finger tips are fairly constant, Galton’s “ simple arch ” being the most reduced form. The palmar, thenar, and hypothenar centres are of un- certain occurrence. As a working hypothesis, Wilder suggests that the epidermic ridges were primitively even and parallel ; that pads evoked by pressure caused divergence of the primary ridges and the formation of secondary ridges y and that in modern walking forms the hypertrophy of the epidermis has obliterated the markings, which arboreal life has retained in the Primates. * Arch. f. Mikr. Anat., xlviii. (1897) pp. 690-2. t Biol. Centralbl., xvii. (1897) pp. 161-79. % Tom. cit., pp. 226-39. § Anat. Anzeig., xiii. (1897) pp. 250-56. 196 SUMMARY OF CURRENT RESEARCHES RELATING TO He does not mean, however, to commit himself to a Lamarckian theory, believing that the facts may be equally well interpreted in terms of selection. There is no reference in the paper to Dr. D. Hepburn’s work 'on the papillary ridges of monkeys and men (1895) — an omission which is surely inadvertent. j3. Histology. Text-Book on the Cell.* — M. L. F. Henneguy has published a series of lectures on the cell, the result being a volume which must take its jplace beside the similar works of Hertwig, Bergh, and Wilson. Giant Ganglion-Cells in Spinal Cord of Flat-Fishes.| — Mr. U. Dahlgren finds a system of giant ganglion-cells in the spinal cord of Paralichthys dentatus, P. oblongus, Bothns maculatus , Plcuronectes cimeri- canus , and other flat-fishes. It consists of a row of very large nerve-cells in the median dorsal fissure and of their processes, which pass backwards and form an isolated fibre tract on the mesial side of each dorsal horn. They are the first ganglion-cells to become diiferentiated in the embryo flat-fish ; they are not preceded or accompanied by a really transient apparatus, and are the only large nerve-cells that appear in the dorsal median fissure. It is suggested that these cells are connected with the sense-organs of the dorsal fin, and that they may be the same as the transient ganglion-cells in the embryos of Salmo, Baja , &c. Structure of Cerebral Cortex and Function of Herve-Cell Pro- cesses.:]:— Dr. K. Schaffer describes the superficial nerve-cells in the brain, and the relations of the axons and their collaterals. He maintains — (1) that nervous stimulus is always propagated only through the axons and their collaterals, the dendrites being nutritive ; and (2) that impulse from a cell passes by the axons, while stimulus to a cell passes by those collaterals whose contact-relations enable them to function as receptive structures. A Centrosome Artifact in Herve-Cells.§ — Dr. U. Dahlgren describes -certain appearances in the spinal ganglion-cells of the dog, which looked exceedingly like centrospheres and centrosomes, but which candid exa- mination showed to be artificial and due to some structural change pro- duced by crystals of sublimate. Sensory Organs of the Lateral Line.|j — Dr. F. S. Bunker has studied these in the bull-head, Ameiurus nebulosus Le Sueur. At the base of the sensory organs, outside the basement membrane, the nerve-fibres lose their medullary sheath, branch repeatedly, and spread out over the whole bottom and sides of the organ. They pierce the basement membrane in jmany places, and rise, still branching, to the bases of the sensory cells, around which they intertwine in a basket-like network, from which fibrillations rise still higher, nearly to the free border of the organ. Other fibres take no part in this basket-like plexus, but extend upwards, still branching, in close apposition to the sensory cells. The latter end in bristles, and are in the strictest sense nerve-elements conforming to .the type of anaxionic neurons. * ‘ Lemons sur la cellule, morpliologie et reproduction,’ 8vo, Paris, 541 pp., 3G2 figs. t Anat. Anzeig., xiii. (1897) pp. 281-93 (4 figs.). X Arch. f. Mikr. Anat., xlviii. (1897) pp. 550-72 (2 pis.). Anat. Anzeig., xiii. (1897) pp. 149-51 (2 figs.). || Tom. cit , pp. 25G-G0. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 197 Red Blood-Corpus sles.* * * § — Dr. E. Giglio-Tos distinguishes four kinds of red blood-corpuscles in Vertebrates : — (1) Primitive erythrocytes , as seen in earliest development. (2) Granular erythrocytes , as seen in the lamprey throughout life, and in embryonic or larval life in other Vertebrates. These are spherical cells with membrane and nucleus, with protoplasm rich in haemoglobin, and with a certain number of granules or drops of haemoglobigenous substance (of nuclear origin). (3) Nucleated ringed erythrocytes ; lenticular elliptical biconvex cells, with a median nucleus surrounded by a stratum of haemoglobigenous substance. Around this central mass is a ring of elastic substance con- taining the haemoglobin. These occur in Sauropsida and Ichthyopsida, except in the lamprey. (4) Non-nucleated ringed erythrocytes ; circular or elliptical discs, in which the haemoglobigenous substance forms a single central mass, around which there is a ring of elastic substance containing the haemoglobin. Behaviour of Leucocytes in Injured Cornea.f — Prof. L. Ranvier describes the role of the leucocytes in the reparation of an injured cornea. As he says, he has previously discussed the migration, nutrition, transporting power, and dissolution of these cells ; as indeed others have done. He objects to the term phagocytes, for that is only a new name for familiar elements, and he objects to that emphasis on phagocytosis which loses sight of the fact that all cells may in certain conditions take in solid particles. He insists on the important role which the leucocytes play in supplying nutritive material to the tissues, and on the view that inflammation is a return to embryonic conditions. Muscle-Fibres.J — Prof. R. Marchesini discusses the structure and development of muscle-fibres in a variety of types. Whether smooth or striped, the muscle-fibre results from the union of embryonic cells (caroblasts), which remain in their primitive state in the smooth fibres, and are transformed into fibrils in the striped. The difference in the structure of the so-called two kinds is wholly due to the degree of development. Peritoneal Ostioles.§ — M. J. J. Andeer maintains that the peri- toneum of the frog, &c., has a fine gauze-like structure, being studded with minute pores or ostioles, which are important both physiologically and pathologically. As he says, they have hitherto escaped the observa- tion of histologists. Suprarenal Capsules. || — Mr. Swale Vincent concludes that the suprarenal capsule of Mammals corresponds to two distinct glands in Elasmobranchs, the medulla corresponding in structure and function to the “paired segmental” suprarenal bodies, while the cortex corresponds to the interrenal body. In Teleosteans, and probably in Ganoids, the suprarenal bodies (“ corpuscles of Stannius ”) consist entirely of cortical substance, and correspond to the interrenal of Elasmobranchs. * Anat. Anzeig., xiii. (1897) pp. 97-109. Atti K. Accad. Sci. Torino, xxxii.. (1897) pp. 237-9. t Comptes Kendus, cxxiv. (1897) pp. 386-91. X Toll. Soc. Kom. Stud. Zool., v. (1896) pp. 198-210. § Comptes Kendus, cxxiv. (1897) pp. 577-80. 11 Proc. Koy. Soc., lxi. (1897) pp. 61-73. 198 SUMMARY OF CURRENT RESEARCHES RELATING TO y, General. Experimental Morphology.* * * § — Mr. C. B. Davenport lias published the first of four volumes which are to bear this title, and which have for their aim to explain what may be called the physiology of growth and development. The present volume deals in a careful and scholarly manner with the reactions of protoplasm to external influences, chemi- cal, mechanical, and dynamic, and with the modifications which these influences sometimes induce. In spite of the author’s preface, we cannot agree that he has found the correct title for his book, which, however, promises to be a very useful one. Problems of Biology. f — Mr. G. Sandeman has published a book which may be called a criticism of some of the categories of biology. After a chapter on biological method, the author criticises three familiar postulates : — (1) That the qualities of the individual are discrete, numer- able, constituent elements, of which the organism is the total sum ; (2) that all the qualities of the organism and all its stages are the mani- festation of, and are related to one another only through an agent or system of agents within the known body ; (3) that everything organic exists only by reason of, and is to be explained only in relation to, some special external use which it now has, or which a similar structure has had in former times. The fifth and last chapter discusses the unity of the organism, which is the central idea of the book. Even by those who maintain that biology has nothing to do with philosophy, and vice versa , Mr. Sandeman’s book will be found stimulating ; while those who believe that to science without philosophy the world remains a broken mirror, will welcome it warmly. And even the least ambitious of biologists may realise from this little book that in his use of the most familiar words, such as “ organism,” “ function,” “ development,” “ evolution,” he is dealing with big and difficult concepts of which progress demands an ever-recurrent criticism. Bionomics of Australasian Animals. :f — Dr. R. Semon has given a popular account of the journeyings which he undertook in order to obtain the young stages of Ceratodus, Echidna , &e. From a review § of the book we select a few illustrations. The chief food of Ornithorliyn- chus consists of a bivalve, Corhicula nejpeanensis. The Monotremes repro- duce once a year. Ripe and fertilised eggs are found only in the left oviduct. When the egg of Echidna is placed in the pouch it measures 5 mm. in length, the newly hatched embryo measures 15 mm., the young one remains in the pouch until about 80-90 mm. in length. It is pro- bable that the dingo is responsible for the disappearance of Thylacinus and Sarcophiius. A remarkable circular nest of stones is made by Arius australis. The importance of drift wood in distribution is very great. In many west- Javanese animals (e.g. Manis javanica, Ptychozoon homalo- cephalum ) there seems to be no special reproductive season. Under the * ‘ Experimental Morphology,’ The Macmillan Co.. New York, 8vo, 1896, xiv. and 280 pp., 74 figs. f ‘Problems of Biology,’ 8vo, London, 1896, 213 pp. X ‘Im Australischen Busch und an der Kiiste des Korallenmeeres. Reise- Ergebnisse und Beobachtungen eines Naturforschers in Australien, Neu-Guinea und den Molukken,’ 8vo, Leipzig, 569 pp., 85 illustr., and 4 maps. § Zool. Centralbl., iv. (1897) pp. 84-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 199 umbrella of a Bhizostomid the fish Caranx auratus was found ; other small fishes seek shelter among the extraordinarily long spines of Diadema setosum. The Plankton Pump.* * * § — Prof. J. Frenzel describes the use (in lakes) of the Plankton pump, which has proved itself advantageous on ice- eovered waters, and is probably capable of much wider utilisation. For slight depths it is both cheap and practicable ; but the cost of the india- rubber tube mounts up with every yard, and what the pump can do in deep water explorations remains to be seen. So far as it has been used, fit compares favourably with even Ilensen’s net. Plankton of Faeroe Channel-t — Dr. G. H. Fowler, in the first of a series of notes on the Plankton of the Faeroe Channel, describes Sagitta Whartoni sp. n., which differs from all other species yet described in the approximation, almost fusion, of the paired lateral fins ; Sjpadella ( Krohnia ) hamata Mobius, of which a better outline figure than has hitherto been given is furnished ; and Salpa asymmetrica sp. n., the eighteenth now recorded from the N. Atlantic. Variation of the Plankton.}: — Dr. J. Hjort has published a very interesting memoir describing his hydrographic-biological studies off the Norwegian coast. He has much to say in regard to the diversity of the Plankton at different seasons. The conditions on wrhich the periodi- cally diverse appearance of the Plankton depends are many and various. Of greatest importance are (1) the ocean currents and the variations in salinity ; (2) the propagating period of the various organisms concerned ; and (3) the variations of wind and light. Physical Basis of Animal Phosphorescence.! — Mr. S. Watase has pub- lished an entertaining lecture on this subject, and promises a monograph. In some historical notes he quotes largely from Faraday, who surmised the results of later workers, showing that a chemical substance, probably a secretion, in the glow-worm and the firefly, shines when exposed to air, independently of the insect’s life, though the insect does in some way control its luminosity. Mr. Watase clears the ground by insisting on the continuity of heat and light phenomena, which differ subjectively rather than objectively. Usually the organism produces heat without light, the firefly produces light without heat. The proximate cause of luminosity in the animal kingdom may be due to a variety of secondary circumstances : — (1) there maybe luminous bacteria present pathologically ; (2) there may be symbiotic luminous bacteria ; (3) the food may be phosphorescent. In fireflies, the luminous cells contain granules, secretions of a fatty nature, 'which oxidise readily in alkaline media. Phosphorus has nothing to do with the phenomenon. The product of cell-metabolism is oxidised in situ and independently of the cell-life, by the inspired oxygen. Through its respiratory mechanism the insect may and does control the process ; but the last step is the oxidation of a dead substance. Watase closes * Biol. Centralbl., xvii. (1897) pp. 190-8. t Proc. Zool. Soc. London, 1890 (published 1897), part 4, pp. 991-G (1 pi.). X Skrift. Yidenskabs. Christiania, 1895, part 1, No. 9 (published 1896), pp. 76 and 75 (15 maps, &c.). § Wood’s Holl Biological Lectures, 1896, pp. 101-18 (1 fig.). 200 SUMMARY OF CURRENT RESEARCHES RELATING TO with the question whether the relation of oxygen to life may not alwayo he of this nature. Fauna of Alpine Lakes.* — M. Otto Fuhrmann gives faunistic lists* which represent a vast amount of work, relating to the Alpine lakes of Tessin. He has discovered numerous forms hitherto recorded only in the plains ; indeed, out of 67 forms, 34 have not been noticed hitherto in these high-lying waters. In short, the Alpine lake fauna is less peculiar than was supposed. Fuhrmann gives an interesting illustration of the- diversity that may exist in adjacent lakes. The Lago Punta Nera (2456 m.) and the Lago Scuro (2453 m.), are separated by 100 m. and united by a stream. The former is small and not deep, the latter is large and deep, otherwise they are much alike. From the former 33 species were obtained, from the latter 17, only 9 common to the two. Of the pelagic forms, only Cyclops strenuus and Diaptomus were common to the two lakes. The littoral forms were even more distinct. INVERTEBRATA. Mollusca. a. Cephalopoda. Oviposition of Nautilus.-f — Dr. A. Willey describes the oviposition of Nautilus macr omphalus, the species characteristic of the New Caledonian Archipelago, differing from N. pompilius in the umbilical region of the shell. The eggs are laid singly and at night, in concealed situations,, and are firmly attached to a suitable surface by a sponge-like reticulate area of attachment placed towards their hinder inflated extremity,, usually on one face of the egg-case, but sometimes quite posteriorly. The ovum is enclosed within a double casing, an inner closed capsule, and an outer capsule more or less freely open in front. These cap- sules are formed of a bright milk-white material, of firm cartilage-like consistency. The egg with outer covering complete is of remarkably large size, attaining a length of 45 mm. and a maximum height of 16-25 mm. The vitellus does not fill the entire cavity of the inner- capsule, but is surmounted by a layer of cloudy viscid albumen. The yolk is of a rich brown colour, very fluid and sub-translucent. The breeding seems to be periodic. Arthropoda. a. Insecta. Means of Defence in Insects4— Prof. L. Cucnot gives a detailed account of reflex bleeding in insects, e.g. in Timarcha , Galeruca, Megalo- pus, Eugaster, and Ephippiger. A preliminary note was previously sum- marised. When disturbed these insects emit drops of blood from the mouth, or from the femoro-tibial articulations, or from the attachment of the elytra. The blood contains toxic, caustic, or repellent substances,, such as cantharidin, and is effectively protective against lizards and amphibians. A flow may be induced by slight chloroforming or other excitation. Compressed by the contraction of the abdomen the blood bursts through the cuticle at the points of least resistance. There is * Eev. Suisse Zool., iv. (1897) pp. 489-543. t Proc. Roy. Soc., lx. (1897) pp. 467-71 (4 figs.), t Arch. Zool. Exper., iv. (1896) pp. 655-80 (4 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 201 some interesting variability : — Thus the place of rupture may be different in the same species ( Timarcha ); some individuals do not show any bleeding ; it seems to occur in specimens of Melasoma at Halle, but not in those of France. Labium of Hemiptera.* — Dr. N. Leon confirms what he discovered in 1887 and in 1892, that the Hemiptera have not only labial palps, but also rudiments of the external and internal lobes. He has investigated Benacus griseus Say, ZaitJici anura , Gerris Najas, Velia rivulorum , &c., and maintains the complete homology between the labium of Hemiptera and that of biting insects. The first joint corresponds to submentum and cardines, the second to mentum and stipites ; the third and fourth joints represent paraglossae or ligulae, or, more probably, both united. Evolution of Lepidoptera.f — Dr. Grafin Maria von Linden discusses Prof. Eimer’s work on the origin of species in Lepidoptera, and especi- ally of the lines of evolution disclosed by a study of the markings. “ It has been shown,” she says, “ that a large number of changes in the individual animal arise from the operation of external influences, that these variations are similar to those observed in nature, and occur like- wise in definite directions. It is also shown that the variations which arise by organic growth are transmitted to descendants, and that the different stages of variation which are exhibited in the phylogeny as specific characters are recapitulated as transient stages in the ontogeny.” “ If Prof. Eimer’s claims are correct,” says Minot, “ his researches mark one of the great epochs of biological discovery.” Growth of Silkworms4 — Sigg. Luciani and Lo Monaco have inves- tigated the progressive increase in the weight and nitrogenous content of silkworms, considered in relation to the nutrition at successive stages. Unusual Case of Myiasis.§ — Dr. G. Alexandrini reports an unusual case of myiasis due to the larvae of Sarcophaga carnaria Meig. in the nasal cavity of man. After describing the case and the treatment, he notes some similar occurrences. Larva of Thrixion Halidayanum.|| — M. J. Pan tel describes some of the structural peculiarities of this Dipterous larva. The gut is sim- plified in adaptation to parasitism ; thus the oesophagus and the hind-gut ■are short, the stomach and gastric appendages are suppressed, and the place of the proventriculus is taken by a hard cushion (with associated musculature) on the upper wall of the oesophagus. The heart— a mus- cular tube closed behind — is also described. More interesting, perhaps, is a metameric organ in the seven abdominal segments. It is formed in -each side of a somite by a twin group of giant-cells, and possibly repre- sents a closed excretory organ. Notes on Strepsiptera.H — Prof. N. Nassonow criticises Prof. F. Meinert’s recent denial of the existence of a cephalothorax in Strepsiptera, .and his identification of the cephalothorax as the posterior end. The * Zool. Anzeig., xx. (1897) pp. 73-7 (5 figs.). t Biol. Centralbl., xvii. (1897) pp. 179-90, 213-2G. X Atti (Rend.) R. Accad. Lincei, vi. (1897) pp. 155-32. § Boll. Soc. Rom. Stud. Zool., v. (1896) pp. 191-7. II Comptes Rendus, exxiv. (1897) pp. 580-2. 1 Zool. Anzeig., xx. (1897) pp. 65-6. 1897 p 202 SUMMARY OF CURRENT RESEARCHES RELATING TO author has confirmed the conclusions of Erichson and Siebold as to the presence of a true cephalothorax. He gives a figure of Xenos Bossii7 showing (a) the supra-oesophageal ganglion with its optic lobes, (b) the oesophageal nerve-ring, (c) the sub-oesophageal ganglion, and (d) the abdominal ganglion, which is fused with (c) in the larvae, but connected with it by a commissure in the adult female. Second Abdominal Segment in Libellulidse.* * * § — Miss M. F. Goddard describes the second abdominal segment and the penis in a few male Libellulinae, species of Diplax, Celithemis , Libellula , and Plathemis. Some general suggestions are offered — e.g. that the hamules may be homologues of abdominal appendages ; and that the bifid condition of the hamules in Libellulinae is secondary, transitions occurring towards the uniramous condition in the other sub-families. Larvae of British Lepidoptera.f — The seventh volume of ‘ The Larvae of the British Butterflies and Moths,’ by (the late) Mr. W. Buckler, published under the editorship of Mr. G. T. Porritt, deals with the first portion of the Geometrae. Mr. G. C. Bignell supplies a list of parasites known to affect the species treated of. It is needless to say more in regard to this well-known work. j8. Alyriopoda. Investigations on Biplopoda.J — Dr. C. Yerhoeff discusses — (1) the comparative morphology of the first pair of appendages in male Iulidm ; (2) the well-marked differences of coloration in the sexes of Brachyiulus projectus Yerh., B. projecins var. aliicolus Yerh., and B. rosenauensis < Yerh., the males being the darker in all three cases ; (3) the occurrence of Schalt-males in Pachyiulus hungaricus Karsch and in Brachyiulus pro- jectus Yerh. ; and (4) three new forms from Siebenbtirgen, viz. Poly- desmus hamaius Yerh., P. illyricus montanus Daday, and P. illyricus Yerh. [= complanatus Daday]. Ovum of Diplopoda.§ — Dr. B. Nernec has investigated the structure of the ovum of Polyzonium germanicum Brdt., Blaniulus guttulatus Boscy and some other Diplopoda. A medium-sized ovum contains a large well-defined cap-like body, on the concave side of which lies the nucleus. The latter shows an achromatic reticulum, and a large round nucleus including a still smaller body. Beside the cap there is also a much smaller corpuscle, around which the plasma is radially disposed (the- attraction-sphere). The cap in question arises from one of two cor- puscles which lie near the nucleus in the young ovum ; it becomes very definite, and embraces the nucleus ; thereafter it becomes vacuolated and breaks up. It is possible that cap and sphere are both differentiations of an originally single corpuscle which divides. 5. Arachnida. New Spiders.|| — The Kev. 0. Pickard Cambridge describes two new spiders, both of which require new genera. The first, Aetius decollates * Proc. Am. Philos. Soc. Philadelphia, xxxv. (1896) pp. 205-12 (2 pis.). t Ray Society, London, 8vo, pp. xv. and 176, pis. cvi-cxxvii. (1897), volume for 1894. % Zool. Anzeig., xx. (1897) pp. 78-88. § Anat. Anzeig., xiii. (1897) pp. 309-12 (15 figs.). U Proc. Zool. Soc., part 3, 1896 (published 1897), pp. 1006-12 (1 pi.): ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 203 (fam. Myrmecidae), is from Ceylon; the second, Friula Walladi (fam. Gasteracanthidae), was found by Dr. A. R. Wallace at Sarawak many years ago. It is a remarkable form, the exterior angle of the diamond- shaped abdomen being prolonged on each side (for more than the width of the abdomen) into a strong cylindrical spine-like projection, directed rather backwards, and enlarged or clavate at the extremity, ending in a group of six or seven small conical prominences. The author also gives an account of the males of Labdacus monastoides Cambr. and StepJmnojpoides brasiliana Keys, the females only having been hitherto described. Epizoic Mite on an Ant.* — M. Ch. Janet describes the occurrence of a mite, Antennophorus Uhlmanni Haller, beneath the head and on the sides of the abdomen of Lasius mixtus Nyl. It feeds on nutritive fluid disgorged— willingly it would seem — by the ant. €. Crustacea. Notes on Crabs.f— Mr. W. Garstang discusses the function of the antero-lateral denticulations of the carapace in sand-burrowing crabs, such as Batliynectes longipes and Atelecyclus heterodon. They subserve a sieve-like function, and the extent of the denticulated area corresponds with the extent of the inhalant gap between the carapace and the cheli- ped, when the latter appendage is approximated to it in the flexed position. In the sand-burrowing crabs with these denticulations, the chelipeds" act as organs temporarily subservient to the respiratory pro- cess by providing a broad oj^erculum to the exostegal channel. Mr. Garstang also describes the systematic features, habits, and respiratory phenomena of Portumnus nasutus Latreille, which has not been previously recorded as an inhabitant of British seas. Again he shows the utility of apparently trivial specific characters. Development and Species of Sergestes.t — Dr. H. J. Hansen gives a brief account of this genus, in regard to which more complete observa- tions are much to be desired. Of the 50 (or 60) hitherto described species, only about 20 have been established on sexually mature forms, and almost all the other species are larval stages, some of them of species previously established on adult specimens. Of the 20 species founded on adult specimens, 2 are excluded for good reasons, and 4 are cancelled as synonyms. When a species is mature, the male always possesses a large petasma, and — so far as we know — a peculiar development of the exterior flagellum of the antennulae. In all larvae ( 3Iastigojpus ) the eyes are yellowish or whitish, and black pigment, when present, is found only in the interior, and very remote from the cornea ; while in the adults the eyes are totally black. With one exception ( S . arcticus) all the species are found in tropical and sub-tropical seas, to lat. 42°-43° N. in the Atlantic. All the larvae are essentially surface forms, but at least two-thirds of the species in- habit the depths of the sea when mature. * Comptes Kendus, cxxix/(1897) pp. 583-5 (1 fig.). t Journ. Marine Biol. Ass., iv. (1897) pp. 396-407 (2 figs.). X Proc. Zool. Soc. London, 1896, part 4 (published 1897) pp.' 936-70. * p 2 204 SUMMARY OF CURRENT RESEARCHES RELATING TO Malayan Decapods and Stomatopods.* * * § — Dr. J. G. de Man con- ' tinues his report on a collection from Malacca, Borneo, Celebes, and the Java Sea. He describes several new species. Notes on Distribution of Amphipoda.t — Mr. A. 0. Walker has made some studies on the proportion of species to genera in small and large areas, and on the distribution of species at various depths. He finds that the proportion of species to genera increases with the area, and that a far greater number of species are found at depths less than 100 fathoms, than at that or a greater depth. From below 50 fathoms, 208 species were recorded, against 74 between 50 and 100 fathoms ; and 57 above 100 fathoms. Sarcotaces arcticus.f — Dr. J. Hjort discusses this strange parasite — perhaps a new type of Cirripedia — which was discovered by Collett (1873), in the flesh of Molva abyssorum , and referred by him to the genus Sarcotaces established by Olsson (1872). The life-history is pro- bably somewhat as follows : — The small ova give rise to nauplius larvae which swim about at a depth of over 100 fathoms ; they perhaps attain to a metanauplius stage, and then fasten themselves to Molva ; after a period of growth they begin to be encapsuled by connective tissue strands developed in the musculature of their host ; this capsule cuts off nutrition, and the parasite lives on the store of blood accumulated in its large digestive cavity; the ovaries, however, ripen, and the eggs are fertilised, perhaps by a rudimentary male ; degeneration sets in, an open- ing to the surface of the host is formed, and nauplius-larvse escape. But much remains quite uncertain as regards both structure and develop- ment. New Epicarid Parasite.§ — M. Maurice Caullery describes Branchio- phryxus nyctiphanse g. et sp. n., one of the Dajidas, which he found on the last gill of Nydiphanes norvegica. In the female, the number of thoracic appendages is reduced to eight (ten being the usual number), and the pleural plates have disappeared ; in both sexes the abdomen is atrophied. The type is thus more degraded than Aspidophryxus, Dajus, or Noto- pliryxus. It shows most resemblance, in part perhaps the result of con- vergence, to Notophryxus lateralis G. O. Sars. Development of Monstrillidae.|| — Dr. W. Giesbrecht calls attention rto Giard’s ^ solution of the riddle involved in the fact that these Cope- pods do not feed during their mature pelagic life, when, however, they are very active and very productive. The solution is found in the earlier life of these animals, when they are entoparasites in Annelids ( Polydora ), and accumulate material for future use. Malaquin ** has recently con- firmed this, but states that the young are found in Filigrana and Salma - cyna in a blastula-like stage. Giesbrecht, on the other hand, finds that the young of Monstrillidae, like other Copepods, leave the egg as nauplii. Jit is possible, however, that after the nauplius stage they lose their * Zool. Jahrb. (Abth. Syst.), ix. (1897) pp. 725-90 (3 pis.), f Proc. and Trans. Liverpool Biol. Soc., x. (1896) pp. 178-80. % Skrift. Yidenskab. Christiania, 1895, i. (published 1896) 14 pp. (2 pis.). * § Zool. Anzeig., xx. (1897) pp. 88-92 (2 figs.). || Tom. cit., pp. 70-2. Comptes Rendus, cxx. p. 937 ; cxxiii. p. 836. ** Op. cit., cxxiii. p. 1316; exxiv. p. 99. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 205- appendages, undergo histolysis, and become the ellipsoid bodies which Malaquin has described. Free-Swimming Copepods from West Coast of Ireland.* — Mr. I. C. Thompson describes the Copepods of some tow-net material from off Valencia. Of 22 species, 6 were rare, viz. Meiridia armata , Candace pectinaia, Pseudocalanus armatus , Monstrilla rigida, Corycseus speciosus, and Oncsea mediterranean The occurrence of the two last, which are southern species, may indicate Gulf Stream influence. The collection, like another made by Prof. Herdman, illustrates the relatively large number of different genera, for the 22 species represent 18 genera. Brain and Optic Ganglion of Leptodora hyalina.f — Mr. E. P. Carl- ton has made a study of the minute structure of these parts. The brain is covered with cortical cells, except at the superficial origin of the nerves and over an area located dorsolaterally. The interior is com- posed of the medulla, or Punldsubstanz, which is divided by commissures and cells into distinct subdivisions, and of three groups of nerve-cells. In the optic ganglion, likewise, there is a superficial layer of cortical cells and a central medulla. The author describes the various parts in detail. South African Entomostraca. J — Prof. G. 0. Sars reared 20 species of Entomostraca from some dried mud obtained from a swamp at Knysna, some distance east of the Cape of Good Hope. Nothing has been hitherto published about the freshwater Entomostraca of that remote region, hence the special interest of this paper. The mud yielded 9 Cladocera, 10 Ostracoda, and 1 Copepod, of which 11 species were apparently new to science. Classification of Trilobites.§ — Mr. C. E. Beecher completes his out- line of a natural classification of the Trilobites. Order A. Hypoparia ord. n. Free cheeks forming a continuous marginal ventral plate of the cephalon, and in some forms also extending over the dorsal side at the genal angles. Suture ventral, marginal, or sub-marginal. Compound paired eyes absent ; simple eyes may occur on each fixed cheek, singly or in pairs. Includes the families Agno- stidae, Harpedidae, and Trinucleidae. Order B. Opisthoparia ord. n. Free cheeks generally separate,, always bearing the genal angles. Facial sutures extending forwards from the posterior part of the cephalon within the genal angles, and cutting the anterior margin separately, or rarely uniting in front of the glabella. Compound paired holochroal eyes on free cheeks, and well developed in all but the most primitive family. Includes the families- Conocorypliidae, Olenidee, Asaphidae, Proetidae, Bronteidae, Lichadidae, and Acidaspidae. Order C. Proparia ord. n. Free cheeks not bearing the genal' angles. Facial sutures extending from the lateral margins of the ceph- alon in front of the genal angles, inward and forward, cutting the ante- rior margin separately or uniting in front of the glabella. Compound * Proc. and Trans. Liverpool Biol. Soc., x. (1896) pp. 92-102. t Anat. Anzeig., xiii. (1897) pp. 293-301 (28 figs.). t Skrift. Yidenskabs. Christiania, 1895, part i, No. 8 (published 1896), 56 pp ,. 8 pis. § Amer. Journ. Sci., iii. (1897) pp. 181-207. 206 SUMMARY OF CURRENT RESEARCHES RELATING TO paired eyes scarcely developed or sometimes absent in the most primitive family, well-developed and schizochroal in tbe last family. Includes tbe families Encrinuridae, Calymenidae, Cheiruridae, and Phacopidae. The Hypoparia probably culminated in the pre-Cambrian times, the Opisthoparia during the Cambrian, and the Proparia during the Ordo- vician. The Opisthoparia are represented by about 85 genera in the Cambrian, 45 in the Ordovician, 19 in the Silurian, 10 in the Devonian, 4 in the Carboniferous, and 1 in the Permian. Annulata. Pelagic Larvae of Polychseta.* — Dr. Y. Haecker describes many of the pelagic larvae of Polychaeta which are to be found in spring in the Gulf of Naples. He distinguishes the trochophore (without hint of metameres), the metatrochophore (in which segments are beginning to be defined), the nectochaeta (with reduced ciliation, but with strong setose natatory appendages), and the protrochophore (without mouth or anus, with broad pre-oral zone bearing short cilia), a stage antecedent to or replacing the trochophore. After defining the various regions of the larval body, the author describes the larvae of the different families. The assumption of a pelagic stage is interpreted as an alternative to the acquisition of a store of yolk. Both are adaptations to secure the nutrition of the young. All possible transitions occur between those forms which become sedentary immediately after being hatched, and those which are from the first pelagic. The author distinguishes four groups : — I. Tubicolous forms with non-pelagic larvae (Terebellidae, Ariciidae, Arenicolidae (?) ; II. Tubi- colous forms with strictly pelagic larvae (Chaetopteridae, Spionidae, Ser- pulidae, Archiannelidae) ; III. Errantia without pelagic larvae (some Eunicidae and Syllidae) ; IV. Errantia with strictly pelagic larvae (Nephthyidae, Nereidae, Phyllodocidae, and Aphroditidae). Not the least important part of this valuable memoir is the third chapter, iu which the author discusses the comparative histology and physiology of the integument — the pigmentation, the primary sense- organs, the locomotor apparatus, the primary^glandular and skeletal tissue. Asymmetry of Spirorbis.j — MM. Maurice Caullery and F. Mesnil describe the asymmetry of Spirorbis induced by its habitat in the interior of a spiral tube. The direction of the turn of the spire is con- stant for a given species ; the operculum is always on the concave side ; the longitudinal muscle-fibres are strongest on the same concave side ; the viscera are thrown towards the same side ; the uncini on the thorax and abdomen are larger and more numerous on the concave side ; the ovules in course of maturation are always on the convex side ; and so on. All can be explained by the movements made by the animal within the tube. The authors distinguish right-handed and left-handed species, and in a detailed memoir (referred to) have applied the facts to a phyloge- netic consideration of the group. In a note on the above, Prof. E. Perrier £ directs attention to some previous observations which he made bearing * Zeitschr. f. wiss. Zool., Ixii. (1896) pp. 74-168 (3 pis., 8 figs.). t Ann. and Mag. Nat. Hist., xix. (1897) pp. 411-3. Comptes Rendus, cxxiv. jjp. 48, 50. % Tom. cit., pp. 50-1. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 207 •on the question of asymmetry, and on the resemblance between Cephalo- branchiate Annelids and Gasteropods. “ The initial asymmetry is no doubt due to an active cause like that which shows itself in Molluscs ; when once the tube is formed, it can accentuate itself by reason of the special conditions of existence it imposes on the animal.” New American Species of Megascolides.* * * § — Mr. F. Smith gives a brief description of Megascolides americanus sp. n., from Pullman, Washington. It is said to be very abundant, and to make burrows •sometimes over fifteen feet deep. It differs from its North American relatives in the presence of numerous small nophridia in each somite instead of two large ones, in the extent of the clitellum, and in several other characters. Regeneration of Fore-gut in Lumbriculus.f — Dr. F. von Wagner described this in 1893 as occurring without the help of the ectoderm. He finds, however, that an unmistakable invagination of ectoderm occurs. At the point where the endoderm of the gut is for a time in contact with the superficial ectoderm, forming a provisional mouth, a true stomodaBal insinking develops. Species of Acanthobdelia4 — Prof. Al. Kowalevski has studied the structure of Acantliobdella peledina Grube, found by Middendorf as a parasite on the fishes of the J enissei, and Acantliobdella Esmontii, found D 7 0. Grimm in the Caspian. The chief interest of the first species is its likeness to Cksetopods ; it may be considered as a transitional form. 1 1 has setae and a body-cavity. The second species is much more like Ncphelis. Rotatoria. New Species of Rotifers from the Illinois River. § — Mr. Adolph Hcmpel gives a short description, with figures, of three new species of Brachionus : — B. variabilis, B. mollis , and B. punctatus. The first is rather a bad name, since all Rotifers vary, and none more so than the different species of Brachionus. B. mollis is peculiar in having a very thin soft glassy transparent lorica, with no spines at all, either anteri- orly or posteriorly. B. punctatus has, since its discovery in America, been found near London by members of the Quekett Club, and also in Russia by Mr. A. S. Scorikow. Trochosphaera solstitialis.il — Dr. C. A. Kofoid reports the finding in the Illinois River and adjacent swamps of this rare and peculiar rotifer, first discovered by Surgeon Y. Gunson Thorpe, R.N., in China, .and described in this Journal in 1893 (p. 147). Rotifera of Sandusky Bay.^T — Dr. D. S. Kellicott gives a prelimi- nary list of rotifers observed at the lake laboratory provided for him by the Trustees of the Ohio State University on Lake Erie. Sixty-seven species are enumerated, with notes of their occurrence. One species, Melicerta flocculosa , is described as new, but no figure is given, which is ■always a great drawback to future identification. * Amer. Nat., xxxi. (1897) pp. 202-4. t Zool. Anzeig., xx. (1897) pp. 69-70 (1 pi.). + Bull. Acad. Sci. St. Petersbourg, v. (1S9G) pp. 1-4. § Bull. Illinois State Laboratory Nat. Hist., iv. 1896. il Science, iv., Dec. 1896, pp. 985-6. 1 Proc. Amer. Micr. See., 1896, pp. 155-64. 208 SUMMARY OF CURRENT RESEARCHES RELATING TO Rotatoria from East Africa.* * * § — Dr. Anton Collin gives an account of some Rotifers observed in East Africa by Dr. Stuhlmann during bis journey with Emin Pasha. The account is based on short notes and drawings, and a very few specimens preserved in spirit, and is therefore very fragmentary, and in many cases the animals cannot be identified. Sixteen species are enumerated, four of which are considered to be new : — Philodina (?) emini , Euchlanis longicaudaia, Bracliionus tetracanthus,. and Noteus Stuhlmanni. Rotatoria of the Neighbourhood of Kharkow.-]* — In this pretentious memoir, entirely in the Russian language, Mr. A. S. Scorikow enume- rates and describes 140 Rotifers found in his neighbourhood, of which the following six are considered new species and varieties: — Polyarthra platyptera var. remata , Triarthra iliranites , Pleurotrocha sigmoidea, Battulus bicornis, Brachionus cluniorbicularis, and BracMonus lineatus. The claim to specific rank appears very slight with most of these, and B. lineatus is certainly identical with Hempel’s B. punctatus mentioned above. Nematohelminthes. Life-History of Trichina.J — Herr Geisse finds, by means of feeding- experiments, that the impregnated females bring forth their embryos in the- tubular glands of the small intestine, and that the embryos pass into the body more by the vascular system than by active migration. Herren R. Hertwig and Graham § find that embryos reach the intra- muscular connective tissue eight days after infection. When the Trichina enters the muscle-fibre, the striping disappears, and the nuclei multiply and grow. The worm is surrounded by a gelatinous modifica- tion of the sarcolemma, proliferating connective tissue, and leucocytes. As the capsule is formed the muscle-fibre disappears at that place. Filaroides in Frontal Sinuses of Skunks.|| — Mr. W. McM. Wood- worth calls attention to the occurrence in America of Filaroides muste - larum van Ben., which is common in martens and weasels in Europe. It causes swellings of the frontal bones of skunks, and probably in other Mustelidre. Platyhelminthes. Fragmentation in Lineus gesserensis.f — Dr. A.*:Brown finds that the zones of fission in Lineus gesserensis coincide with the transverse markings ; that the fission is a process of digestive solution (by the fluids of the gut), and proceeds from within outwards ; that there are- circular outgrowths of intestinal epithelium corresponding to external grooves; that, as the result of opposing pressures outwards and inwards, atrophy, disintegration, and disappearance of the outermost cells of the intestinal outgrowth take place, bringing the body-wall into contact with the digestive cavity ; that the ruptured surfaces are at once covered. up by the intestinal outgrowth, and by proliferation of the subjacent * ‘ Rotatorien, Gastrotrichen und Enlozoen Ost-Afrikas, von Ant. Collin,’ 14 figs. t ‘ Rotatoria of the Neighbourhood of Klmrkow,’ 1896, 168 pp., 3 pis. (in Russian). % Miinchener med. Wochenschr., xlii. (1895) p. 655. Zool. Centralbl., iv. (1897)> pp. 96-7. § Miinchener med. Wochenschr., xlii. (1895) pp. 504-5 (4 figs.). Zool. Centralbl., iv. (1897) p. 97. || Amer. Nat., xxxi. (1897) pp. 231-5. T Proc. Roy. See., Ixi. (1897) pp. 28-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 20$ connective tissue wliich aids in healing the fragments. The intestinal epithelium changes in character as it takes up its new external position. The whole process of fission has evident relationships to the process of reproduction. Connective-Tissues and Body-Cavities of Nemerteans.* — Dr. T. H. Montgomery, jun., has investigated species of Carinella , Cerebratulus Linens , Amjohiporus , Tetrastemma, and Stichostemma , and draws the fol- lowing general conclusions : — The connective tissue with dense intercellular substance, the paren- chyma, and the intracapsular tissue of the nervous system, occur in all these genera. A true mesenchyme tissue was found only where there was- an evident perivisceral body-cavity. A pigmented connective tissue with- out intercellular substance, situated in the muscular body wall, is possessed only by Lineus. The branched connective tissue cells with a more or less dense intercellular substance form the basal membranes of the epithelia and endothelia, the elements between the muscle-fibres or bundles, the nerve-sheaths, &c. True parenchymatous tissue with walled cells, without intercellular substance and extraneous cell-fibres, reaches its greatest quantitative development in Carinella and Cerebratulus , and is least in Stichostemma ; it is absent on the lateral blood-vessels in Lineus and the Metanemertini, and in the head and oesophageal regions in all the species. It probably functions as a layer for the mutual transfusion of the rhynchocoelomic and blood fluids. The cells of the intracapsular connective tissue of the nervous system are, in all species except perhaps Stichostemma, divisible into two categories : — (a) those between the outer and inner neurilemma ; and (b) those around and within the fibrous core. A noticeable body-cavity is undoubtedly present in Carinella and Cerebratulus , and in a more reduced state in Lineus gesserensis, Amphi - porus, and Stichostemma. It consists of a slit between the intestine and proboscis-sheath, and the body-wall ; in Cerebratulus it is a very evident cavity, with both fixed and free mesenchyme cells. There is none in Metanemertini. The gonadal membrane is apparently always a product of the con- nective tissue cells, with dense intercellular substance ; the genital cells are either derivatives of cells of this tissue (in Lineus and the Metanemer- tini), or of mesenchyme cells (in Carinella and perhaps Cerebratulus). In the adult Nemertean, amitotic division is seen in the mesenchyme- cells ; but no cell-divisions occur in the other connective tissues, except those true mitotic divisions (in the tissue with intercellular substance)- which give rise to the genital cells. The relationships of the various Nemertean connective tissues may be- illustrated graphically as follows : — I. Parenchyma. II. Mesenchyme. 1. Intracapsular ] connective U A tissue I B. Connective tissue with intercellular substance. 2. Interstitial I tissue of body ><- epithelium ) 3. Pigment-tissue of body- wall (Lineus). * Zool. Jahrb. Abtli. Anat., x. (1897) pp. 1-46 (4 pis.). 210 SUMMARY OF CURRENT RESEARCHES RELATING TO [Maturation and Fertilisation in Prosthecerseus vittatus.* — Dr. A. von Klinckowstrom describes these processes in the ova of this large marine Planarian, which appears to afford very excellent material for such studies. About half an hour after oviposition the first polar body is given off. It shows active amoeboid movements for four or five hours. Two or three hours after the first the second polar body is given off. In an hour or two the cleavage is in active progress ; in 15-20 hours the 16-cell stage has been reached. The peculiar nuclear metamorphosis which Selenka described in Thysanozoon does not occur in Proslhecerseus ; the division-figure in the uterine ovum is simply the first directive spindle. The author gives the following scheme of the maturation- process, the letters meaning chromosomes, of which there are typically twelve, admitting of 853,776 possible combinations in fertilisation : — , ... Id ) I 1st directive spindle with six l bivalent chromosomes. I’ •* ' Yin — - — equation division I a b , c cl, ... Id \ f 2nd directive spindle with /« c k\ | reduction division V cV in m , n, o, p , q , r a, c, e, g, i, h b, cl, ... I 2nd polar body male pronucleus female pronucleus m, n, o, p, q, r, a, c, e, g, i, 1c 1st cleavage spindle. Male Organs of Stenostoma leucops 0. Schm.f — Herr H. Sabussow points out the defectiveness of our knowledge in regard to the reproduc- tive organs of Turbellarians. He sets himself to remedy this by a careful description of the male organs of Stenostoma leucops O. Schm., which consist of five parts — an unpaired testis, an almost spherical vesicula seminalis, a tubular penis without chitinous parts, a penis- sheath, and a small antrum masculinum. Hew Ectoparasitic Triclad4 — Herr L. A. Jagerskiold describes Micropharynx parasitica, found on Baja clavata and B. batis. It is a quite typical Triclad, without marked adaptation to ectoparasitic life, except that it has no eyes, thus differing, inter alia, from the other para- sitic Triclad Bdelloura limuli v. Graff. a b, ci /ah c V7V c ab, cd, ... Id 1st polar body * Arch. f. Mikr. Anat., xlviii. (1897) pp. 587-605 (2 pis., 3 figs.), t Zool. Jahrb. (Abtli. Syst.), x. (1897) pp. 47-54 (1 pi.). X Ufversigt K. Yetensk. Akad. Forhandl., 1896, pp. 707-14 (3 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 211 Echinoderma. Pseudopodia in Echinoderm Ova and Embryonic Cells.* * * § — Gwendolen F. Andrews observes that the ova, polar bodies, blastomeres, and even later embryonic cells, of starfish and sea-urchins, give off delicate ana- stomosing pseudopodial filaments like those of Rhizopods. It is claimed that these are concerned in the formation of the egg-membrane, that they connect the cells during cleavage and gastrulation so that the protoplasm is continuous, and that they may be the basis of cytotropism and of co- ordinating communication in embryonic cell-aggregates. The obser- vations are described under the title, “ Spinning powers of certain eggs.” Palaeozoic Ophiuroids.-j-— Dr. J. W. Gregory gives a synopsis of a classification with diagnoses of some of the genera. He recognises two orders : — (1) Lysophiurae (ambulacral ossicles alternate, free ; no ventral arm-plates) ; (2) Streptophiurae Bell (vertebral ossicles present with more or less Streptospondyline articulations). The first order includes Protasteridae and Palaeophiuridae ; the second includes Ophiurinidae, Lapworthuridse, Eoluidse, Onychasteridae, and Eucladiidae. Muscle-Fibres of Holothurians.J — Dr. N. Iwanzoff finds that if the internal organs of Holothuria tubulosa and Stichopus regalis be treated intra vitarn with methylen-blue, by injection or otherwise, certain muscle-elements react like nervous elements. It seems as if those elements which behave in this way were in a normal state of exhaustion, marked by the presence of a granular product of metabolism, which has a strong affinity for methylen-blue. Perhaps the same is true of nervous elements. Ccelentera. Diversity of Structure in Metridium.§ — Prof. G. H. Parker shows that uniformity of structure is by no means a general characteristic of Metridium marginatum Milne Edw. As in some other Actinians, there are variations in the number of siphonoglyphs and in the number and relations of the mesenteries. The author distinguishes monoglyphic and diglyphic types ; but it is uncertain whether these are varieties or whether the species is dimorphic. It is possible that the two forms may be associated with sexual and asexual reproduction. Porifera. Sponges of Amboina.|] — Dr. E. TopSent describes a collection from the Bay of Amboina. It included more than 80 species, of which 27 were new species or varieties. The collection was made in the Madre- pore zone, and was characterised by the absence of Hexactinellida, the abundance of Monaxonida (especially Haploscleridas), a sparse represen- tation of Calcarea, a notable proportion of Tetractinellida and Mono- ceratina. The Carnosa were represented by three interesting forms : — * Journ. Morphol., 1807, pp. 367-89. See Amer. Nat., xxxi. (1897) pp. 242-5. t Proc. Zool. Soc., part 3, 1896 (published 1897), pp. 1028-14. X Arch. f. Mikr. Anat., xlix. (1897) pp. 103-13 (1 pi.). § Bull. Mus. Comp. Zool. Harvard, xxx. (1897) pp. 259-73 (1 pi.). U Rev. Suisse Zool., iv. (1897) pp. 421-87 (4 pis.). 212 SUMMARY OF CURRENT RESEARCHES RELATING TO Chondrosia reniformis, not hitherto recorded from the Far East, Placortis simplex , hitherto known only from the Mediterranean, and Placinoloplia Bedoti g. et sp. n. Protozoa. Monograph on Coccidia.* — M. A. Labbe completes his systematic account of the various species of Coccidia, and gives a diagnostic key,, with a list of their hosts. The second part of the memoir is devoted to a discussion of the structure — the areolar cytoplasm, the reserve-gra- nules in the meshes, the nucleus, and the centrosome. In the next chapter the author describes the life-history of these parasites, (a) the penetration of the sporozoite into a cell ; ( b ) its transformation into a spherical Coccidium ; (c) the nutrition and growth of this phase ; and (d) its encystation and reproduction by internal division or by sporulation. In the sporulation there is a distinct chromatin reduction, comparable to the expulsion of a polar body. No conjugation has been observed, though its occurrence is suggested by the dimorphism of the spores in Pfeifferia. The last chapter discusses some general features of the life of Coccidia : — their habitat in Vertebrates rather than Invertebrates, their restriction to cpithelia, the manner of infection, the adaptation of parasite to host, individual and phylogenetic variations, relationship with Gre- garines, and so on. * Arch. Zool. Exper., iv. (1896) pp. 549-654 (7 pis., 19 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 213 BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-Structure and Protoplasm. Influence of Light on Cell-Division.* — Herr W. Lohmann has made experiments relative to the influence of intense light on Saccharomyces cerevisise and other yeasts. As source of light, a 15-ampere arc lamp and direct sunlight were used. Pure cultivations equally disseminated in wort-gelatin were exposed to the light, and after a certain exposure the newly formed cells were counted. From a great number of countings it was found that strong electric light exerted an inhibitory influence on cell-division in S. cerevisise. Direct sunlight acted in a similar way. Heterotype Divisions in Lilium Martagon.t — According to Miss E. Bargant, there are two series of nuclear divisions in the life-history of Lilium Martagon which exhibit 12 chromosomes instead of 24, viz. : — I. Spermatogenesis. (1) First division of pollen-mother-cell nucleus ; (2) second division of pollen-mother-cell nucleus ; (3) division of pollen- grain nucleus into vegetative and generative nuclei ; (4) division of generative nucleus in pollen-tube. II. Oogenesis. (1) Division of primary embryo-sac nucleus into micropylar and chalazal nuclei ; (2) division of micropylar daughter-nucleus; (3) division of both daughter-nuclei of micropylar nucleus. The second and third divisions in both series are precisely similar to vegetative nuclear divisions, except in possessing only half the number of chromosomes ; they are called homotype. The first nuclear division on either side is termed lieterotype , because the process of karyokinesis differs from that of the vegetative nucleus. The chief points which distinguish it are : — (1) The resting nucleus, after some increase in size, passes into a contracted state called synapsis ; (2) the chromatic ribbon of the spirem is not homogeneous, but is composed of an erythrophilous ribbon bearing a double row of cyanophilous dots; (3) longitudinal fission appears in the spirem ribbon before its division into chromosomes ; (4) a second longitudinal fission appears in each segment of the immature chromosomes ; (5) the segments •of each chromosome are tightly twisted on each other, and separate from near the middle or from either end; the chromosomes of the diaster stage are usually V-shaped. Formation of the Endosperm in Leucojum-J — Dr. L. Buscalioni records some anomalous instances of karyokinetic division of the nucleus in the formation of the endosperm in Leucojum vernim. During mitosis he has constantly observed, at the poles of the secondary nuclei or at the sides of the equatorial disc, a protoplasmic cord strongly stainable by haematoxylin, which advances more or less towards the periphery of the * Inaug.-Diss. Rostock, 1896. See Centralbl. Bakt. u. Par., 2te Abt., ii. (1S96) _pp. 797-8. t Kep. 66th Meeting Brit. Ass., 1896, p. 1021. Cf. this Journal, 1896, p. 640. X Atti R. Aecad. Lincei, vi. (1897) pp. 187-8. 214 SUMMARY OF CURRENT RESEARCHES RELATING TO cell, sometimes finally reaching the cell -wall. Another anomalous process- is termed by the author gemmation. The nucleus puts forth emergences,, which subsequently become detached. This was observed especially with nuclei of very large size, and sometimes all stages of the process were met with in the same cell. It is probably a process of degeneration. (2) Other Cell-Contents (including Secretions}. 1 Pigments of Plants.* * * § — Miss M. J. Newbigin gives a detailed account of the various colouring matters of plants, dividing them into lipo- chromes, which are insoluble, and anthocyans, which are soluble in water. There is no evidence that lipochromes are in any way deriva- tives of chlorophyll. The authoress groups them in two classes — eucarotins and carotinins. Anthocyans are probably derivatives of tannins. The usual theory, that their purpose is to prevent the decom- position of chlorophyll in . a strong light, is scarcely in harmony with some of the conditions under which they are commonly formed, as, for instance, in young shoots in spring and in autumn leaves. Etiolin is probably nearly allied to chlorophyll, which it resembles in containing nitrogen, while most other plant-pigments are non-nitrogenous. Formation of Gum by Aralia spinosa.f — M. L. Lutz finds the seat of formation of gum in this species to be almost exclusively the phloem of the vascular bundles ; the cortex, pericyclo, xylem, and pith are almost unaffected by it. It is formed alike in the root, the stem, and the leaves. The process goes through two stages ; the first is very rapid, resembling the formation of mucilages ; the second is much slower, partaking more of the character of the production of a true gum. „ Colouring-Matter of the Tomato.J — Herr C. Ehring finds the pig- ment of the tomato to be a cholesterin closely allied to the carotin of the petals of Calendula. (4) Structure of Organs. Young Form of Plants.§ — Prof. K. Goebel adduces a variety of instances, chiefly belonging to the Muscinem and Pteridophyta, in which the young form — protoneme, prothallium — is more or less retained in later life, or in which it can be again called into existence, especially by placing the plant in unfavourable vital conditions. This is especially well seen in Funaria hycjrometrica. If the rudimentary buds are culti- vated in the dark, they revert to a protoneme condition, even after the wedge-shaped apical cell has already been formed, the cells growing out into filaments. In Schizostega osmundacea a similar process takes place in nature, shoots of limited growth being formed, the rudimentary leaves of which, together with their apical cell, are of only temporary duration. In Ferns, shutting off the light will cause the prothallium to revert to * Trans. Bot. Soc. Edinburgh, xx. (1896) pp. 534-50. t Bull. Soc. Bot. France, xliii. (1896) pp. 513-6 ; Journ. de Bot. (Morot), xi. (1897) pp. 91-5 (2 figs.). Cf. this Journal, 1896, p. 81. + ‘Ueb. d. Farbstoff d. Tomate,’ Munster, 1896, 35 pp. See Bot. Centralbl.,lxix. (1897) p. 154. § SB. Iv. Bayer. Akad. Wiss. Munchen, 1896 (97), pp. 447-97 (16 figs.). Cf. this- Journal, 1889, p. 550. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 215 a filamentous form. Analogous results were obtained with flowering plants (Monocotyledones and Dicotyledones), a reversion to the early form of leaf being brought about by unfavourable conditions of air or soil. In some Gymnosperms (Biota, Chamsecyparis) the young form appears to have become fixed. Geophilous Plants.* * * § — Herr 'A. Rimbach has studied the structure and biological phenomena of geophilous plants, i.e. of those in which stem-structures penetrate the soil for the purpose of assisting in the nutrition of the plant, or for purposes of propagation. These differ from one another in a variety of ways. Thus the main underground cauline axis may be vertical or horizontal ; it may be persistent or may die at an early period ; the roots may be contractile or not, and may break up into fragments or not ; the accumulation of reserve-material may be chiefly in the stem, the leaves (bulbs), or the root. Nearly allied species may differ widely in these respects ; while, on the other hand, similar biological characters may be exhibited by species in no way re- lated to one another. Thus Banunculus bulbosus and Gladiolus communis closely resemble one another in these respects ; also Anemone nemorosa and Paris quadrifolia; and again, Oxalis elegans and Tigridia pavonia. Opening of the Flower of (Enothera.j — M. L. Planchon has inves- tigated the phenomena connected with the sudden opening in the evening of the flowers of CEnothera Lamarckiana, and suggests the following interpretation : — At sunset the afflux of sap and decrease of transpiration cause a general swelling of the bud, and especially of the corolla. This accounts for all the phenomena of opening. By their swelling the petals detach the calyx, and tbe reflex of the sepals is the result of a swelling of their upper surface in consequence of a special anatomical arrange- ment. The opening and unfolding of the petals is then effected by further swelling of their lamina, accompanied by enlargment of the disc. The fall of the flower the next day is the result of dissociation of the cells which unite the calvcine tube with the ovary. Deviations in the Flower of Polygonum.J— Prof. J. W. H. Trail gives a description of the variations in the flower of several species of Polygonum , especially in P. Persicaria and aviculare . These include suppression of one or more of the segments of both perianth-whorls ; cohesion of two or more segments; chorisis of segments; cohesion, chorisis, and abortion of stamens ; adhesion of stamens to perianth ; and petalody of stamens. The variability appears to express the result of an innate tendency to vary where not subject to the check of loss of fertility. The pistil frequently exhibits reduction to two carpels ; the single ovule in the ovary appears to be a constant character. Flower and “Nipples” of Salisburia.§ — Prof. K. Fujii has studied the nature of the excrescences known as “ nipples ” (chichi) on the stem and branches of Salisburia adiantifolia (Gingko biloba ). They form pendent cylindrical or conical bodies on the under side of the branches, occurring also on the root. They are apparently formed from the coaii- * Ber. Deutsch. Bot. Geselh, xv. (1897) pp. 92-100. f Bull. Soc. Bot. France, xliii. (1896) pp. 455-76 (10 figs.). Cf. this Journal, 1896, p. 330. X f'eP- 66th Meeting. Brit. Ass., 1896, pp. 1016-7. § Bot. Mag. (Tokio), ix. (1895) pp. 440-4 (1 pi.). 216 SUMMARY OF CURRENT RESEARCHES RELATING TO tion of a number of adventitious buds, and rre probably of a purely pathological character. The same author * * * § gives an account of the different views hitherto held regarding the morphology of the flower in the same species. Hairs on the Sepals of the Santalaceae.f — M. P. van Tieghem calls attention to the remarkable fact that the tuft of hairs which springs from the sepals behind the stamens in plants belonging to this order, is not trichomic, but is of endogenous origin, springing from large exodermal cells. This is well seen in Thesium Jmmifusum, and is general throughout the order ; but in the allied families, Arionacem and Schoep- fiaceas, the hairs, though occupying the same position, have an ordinary epidermal origin. Phanerogams with an Ovule destitute of Nucellus.j; — M. P. van Tieghem gives further details of this group of Phanerogams (or of Dicotyledones), the Inovulat^: or Loranthineae, characterised by the absence of any true ovule, and composed of ten orders, the Nuytsiaceae, Elytranthaceae, Dendrophthoaceae, Treubellaceae, Loranthaceae, Arceu- thobiaceoe, Helosaceae, Grinalloaceie, Yiscaceae, and Balanophoracefe. Of these orders the first five, comprising the Loranthales, have hermaphro- dite and dichlamydeous, the remaining five, the Vise ales, unisexual and apetalous flowers. The greater number are clilorophyllaceous parasites ; the Helosacem and Balanophoraceae are non-chlorophyllaceous root- parasites. Closely related to the Inovulatae, and forming a border-land between them and those endowed with perfect ovules, are a group of orders •which the author names the Innucellatas, or Santalinese , in which the ovule is reduced, not to a nucellus, as stated by previous authors, but to the funicle or ovular leaf not differentiated into petiole and lamina; the nucellus and the integument being both entirely wanting. To this group belong nine orders, viz. : — the Santalaceae, Arionaceie, Schcepfiacese, Sarcophytacese, Myzodendraceae, Opiliaceae, Olacacese, Aptandraceie, and Harmandiaceae, the characters of each of which are described in detail. Tn all of them the mother-cell of the endosperm and of the oosphere (improperly called the embryo-sac), originates directly beneath the epi- derm in the cortex of the foliar leaf, without this cortex becoming elevated above the surface and forming the emergence known as the nucellus. These nine orders comprise about fifty genera, five of them mew. The last-named three orders possess a corolla, and constitute the alliance of the Olacales ; the remaining seven, which are apetalous, make up the alliance of the Santalales. They all agree with the Loranthineae in the ripe fruit containing no true seed. The Anthobolaceae, comprising four genera, are distinguished from the above-named orders in possessing a nucellus, but no integument ; they constitute a new group, the Integminat-e or Anthobolinea:. Winged Fruits and Seeds. § — Dr. C. von Wahl classifies the contri- vances for assisting in the carriage of seeds or fruits through the air by * Op. cit., x. (1896) pp. 7-8, 13-5 (1 pi.). f Journ. de Bot. (Morot), xi. (1897) pp. 41-5. ~ X Bull. Soc. Bot. France, xliii. (1896) pp. 543-77 ; Comptes Bendus, exxiv. <1897) pp. 655-60, 723-8, 803-5. Cf. this Journal, 1896, p. 206. § Biblioth. Bot., Heft 40, 1897, 25 pp. and 5 pis. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 217 the agency of the wind under six types, viz. (1) The Acer-type ; (2) the Fraxinus- type ; (3) the Dipterocarpus-tyige ; (4) the Halesia-tyipe (5) the Ulmus-typc ; (6) the Bignonictcese type. The nature of the me- chanical contrivance is uniform in each type, whether it belong to the fruit or the seed, and is often entirely independent of the systematic affinities of the species. To the first type, which the author regards as presenting the most perfect construction for attaining the desired end, belong the samarae of the various species of Acer ; those of a number of species of Malpighiaccae ; of Securidaca among Polygalacese ; of several species of Leguminosae and Sapindaceae ; of Bajania among Dioscoreaceae ; and the seeds of many Coniferae, such as Finns and Larix ; and of many Cedrelacere and Melinceae. The second type occurs in Fraxinus and Liriodendron. The third, which bears a strong resemblance to a shuttle- cock, is generally diffused through the Dipterocarpaceae. The fourth occurs in Halesia and Combretum. The TJlmus type occurs also in Ftero- carjpus and Paliurus . To the sixth type, which is represented chiefly by the seeds of the different genera of Bignoniaccae, belongs also the fruit of Welwitschia. Septal Nectaries.*— Herr J. Schniewind-Thies treats of the nectaries situated in the septa of the ovary which are peculiar to certain orders belonging to the Liliiflorae and Scitamineae. The author classifies them under a number of different groups ; the simplest form occurring in Tofieldia 'palustris, where the nectar is excreted from the entire outer wall of the ovary; while in T. calyculata the secretion is limited to the furrows in the ovary which correspond to septa. The nuclei of the secreting tissue are distinguished from those of the parenchyme by the large amount of chromatin which they contain, and usually by the greater number of nucleoles. In most nectaries the nuclei are erythro- philous. Unusual positions of the nectaries occur ; — in the apex of the style of Leucojum vernum ; in the apex of the ovary of Galanthus nivalis ; and as club-shaped, or some other form of outgrowth on the ovary of the Zingiberaceae. Leaves of Ranunculacese and Umbellifer80.| — Herr G. Bitter points out, in a great number of examples, the remarkable similarity in the types of leaves in these two families. In both orders the phyllotaxis is, with very few exceptions, alternate (spiral) ; stipules are almost invari- ably wanting, and the petiole is commonly expanded laterally. A very deep and complicated division of the lamina is common ; hut in both orders we have species with narrow undivided lamina, and nearly parallel venation ( Banunculus gramineus , Bupleurum). On the other hand a heath-like foliage occurs in a large group of Umbelliferse in the Cape and Australia, but is altogether wanting in the Banunculaceae ; while pedate leaves occur in the latter, but not in the former family. Leaves of Arum italicum.J — Prof. G. Arcangeli discusses the cause of the variability in the leaves of this plant, which are sometimes fur- nished with a number of white or yellow spots, sometimes entirely * ‘Beitr. z. Kenntn. d. Septalnektarien,’ Jena, 1897, 88 pp. and 12 pis. See Bot Centralb]., lxix. (1897) p. 216. t Flora, lxxxiii. (1897) pp. 223-303 (31 figs.). t Bull. Soc. Bot. I tal., 1896, pp. 321-4; 1897, pp. 46-8. 1897 Q 218 SUMMARY OF CURRENT RESEARCHES RELATING TO without spots ; and suggests that it may be connected with the attrac- tion of insects for the purpose of pollination. £. Physiology. (1) Reproduction and Embryology. Fertilisation of the Bromeliacese.* — Herr E. Ule has examined the structure of the flower in connection with fertilisation in several species of Brazilian Bromeliaceae belonging to the genera Nidularium, Quesnelia , . JEchmea , and Chevallieria. They frequently exhibit the phenomenon of cleistopetaly or pseudo-cleistogamy , i.e. the corolla is nearly or quite closed, and the flowers are nevertheless habitually cross-pollinated, usually by humming-birds, which open the corolla by their beaks, being attracted either by the scent, or by the bright colour of the corolla or of the bracts. Self-pollination is, however, not impossible ; and cleisto- petaly may often be a step towards cleistogamy. With the Bromeliaceae these flowers pass gradually into ordinary open flowers. (2) Nutrition and Growth (including Germination, and Movements of Fluids). Organic Nourishment of Green Plants, j — Dr. T. Bokorny discusses the reason why chlorophyllaceous plants are able to assimilate certain organic compounds, while others are useless to them. Thus C02 is readily ^converted into CeH^O^; while plants cannot form any carbohydrate out of CsH803 (glycerin). As a general rule, compounds with one atom of C are readily assimilable, the difficulty increasing with the increase in the atoms of C ; those which contain C and H only are not so favour- able as those which consist of C and 0 only, or of C, H, and 0. Pepton is a peculiarly excellent food-material for Fungi, and probably also for Algae. Starch can often be formed from grape-sugar or cane-sugar only through the influence of light. Free acids are always injurious to the protoplasm. Asparagin is readily converted into proteids in the dark. CH20 (formic aldehyd) is probably always the first product of assimi- lation. Influence of Light on the Growth of Plants.^ — A series of experi- ments on this subject by Herr K. Stameroff leads him to the following- conclusions : — The vegetative hypliae of Mucor and Saprolegnia grow with equal rapidity in light and in dark. Light has a retarding effect on the growth of the reproductive hyphae of Mucor. The rhizoids of the bulbils of Mar chantia] poly morpha grow more slowly in the light than in the dark. Light has no effect on the rapidity of growth of the pollen- tubes of Colutea arborescens or 1 lobinia pseud-acacia. The vegetative hyphae of Mucor and Saprolegnia and the rhizoids of the bulbils of Mar- cliantia grow entirely at the apex. The pollen-tubes of Colutea and Bobinia exhibit irregularities in their growth, the variations following the law of the great period. The rate of development of the pollen- tubes, and their size, depend on the supply of sugar. c * Ber. Deutsch. Bot. Gesell., xiv. (189G) pp. 407-22 (1 pi.). t Biol. Centralbl., xvii. (1897) pp. 1-20, 33-48. % Flora, lxxxiii. (1897) pp. 135-50. Cf. this Journal, 1896, p. 540. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 219 Assimilation of Ammoniacal Nitrogen and Nitric Nitrogen.* * * § — MM. B. Laurent, E. Marchal, and E. Carpiaux report the results of a series of observations on the assimilation of ammoniacal nitrogen and nitric nitrogen by the higher plants. The general conclusions are that, in the higher plants, the assimilation of nitrates does not take place in the dark ; the action of the ultra-violet rays is necessary for it. For the assimilation of ammoniacal salts, the action of the same rays is predomi- nant, but the luminous rays may incite a feeble assimilation of ammonia in etiolated leaves. The action of chlorophyll is not necessary ; etiolated leaves assimilate ammoniacal nitrogen even better than green leaves. The assimilation of nitric nitrogen gives rise to a temporary production •of ammonia. Function of Calcium Oxalate.j — From a series of observations, made chiefly on the rhizome of Humex obtusifolius, grown in various soils and in the dark, Herr G. Kraus has arrived at the conclusion that calcium oxalate is by no means invariably an excretory product, but that it performs the function of supplying the necessary lime for the aerial portions of the plant. Similar results were obtained as to the function of this substance in the bark of various trees and shrubs. With the Cactacese the results were mainly negative, though not conclusive. The only possible solvent for calcium oxalate in the cell-sap is a free -acid. Germination of Barley.J — Mr. T. 0. Day publishes a series of ob- servations on the germination of barley with restricted moisture, the results being shown in a number of tables. An increase of moisture during germination always induces a corresponding increase in the carbon dioxide produced. Taking the production of carbon dioxide as the measure of growth during germination, the period of greatest activity, with varying quantities of moisture, is generally about the third or fourth day. Influence of the Stock on the Graft.§ — By grafting the same variety ■of the pear on two different stocks, the wild pear and the quince, MM. G. Riviere and G. Bailbache have attempted to determine the question of the influence exercised by the stock on the graft. They find, as a general result, that the mean weight of the fruit produced is con- siderably greater in the plants grafted on the quince ; that the density •of the fruit is also greater, and that the amount of free acid and of sugar is also larger. Vitality of Seeds.|| — As the result of further observations on this subject, Dr. A. J. Ewart states that the resistant power of a seed to desiccation is partly dependent on the nature and thickness of the seed- coats, partly on the form in which the reserve food-material is stored. Other conditions being similar, albuminous seeds are the least resistant to desiccation, oily seeds next, and starchy seeds most resistant. * Bull. Acad. Roy. Sci. Belgique, xxxii. (1896) pp. 815-65. t Flora, lxxxiii. (1897) pp. 51-73 (2 figs.). x Traus. Bot. Soc. Edinburgh, xx. (1896) pp. 492-501 (2 figs.). § Comptes Rendus, cxxiv. (1897) pp. 477-80. | Proc. Liverpool Biol. Soc., x. (1896) pp. 185-90. Cf. this Journal, 1895, p. 72. 220 SUMMARY OF CURRENT RESEARCHES RELATING TO Latent Life of Seeds.* — Pursuing his experiments on this subject, M. 0. de Candolle finds that if seeds of maize, oat, fennel, Mimosa ]?u- dica, Gloxinia , and other plants, are exposed for 118 days to a tempera- ture of — 40° F., the majority will still germinate. The protoplasm of the seeds is described as not actually living, but as having reached a stage of inaction in which it is still endowed with potential life. Changes in the Tentacles of Drosera produced by Feeding-! — Miss L. Huie describes the remarkable changes produced in the cells of the tentacles of Drosera rotundifolia by feeding the leaves with white of egg. As the result of this stimulation the basopliile cytoplasm is used: up, and is represented ultimately by a very scanty eosinophilous plasm. The restoration of the cytoplasm is brought about by the nucleus absorb- ing food-material, and then excreting it into the protoplasm. Temporary Suspension of the Action of Chlorophyll.! — Prof. W. Pfeifer calls attention to the arrest of the assimilating function of chlo- rophyll-grains under unfavourable vital conditions, or through the action of reagents, which is only temporary, if these conditions last but for a short time. During this period they undergo no change of form or colour ; respiration becomes feeble, but is not entirely suspended. Iso- lated chlorophyll-grains can assimilate for a time when exposed to light. (3) Irritability. Mechanism of the Phenomena of Sensitiveness. § — Prof. A. Borzi sums up as follows his conclusions as to the mechanism of the motile phenomena resulting from a blow or from sharp concussion. The cause lies in special protoplasmic elements, differentiated physio- logically as organs for the reception and transmission of the irritation. They consist of very delicate fibres, and in general of cells arranged in longitudinal rows in the direction followed by the irritation, and consti- tute definite anatomico-physiological plexi. The cells have a very thin membrane which is very contractile, and is endowed with well-marked osmotic properties. Minute perforations, adapted for the passage of very fine protoplasmic threads, often traverse their walls. The action of stimuli which induce variations in the state of imbibition of the proto- plasm is followed by a rapid change in the turgor and tension of the cells, thus changing the position of the irritated organ. For the purpose of retaining temporarily the water expelled from the protoplasm during the variation in its osmotic condition, every sensitive plexus is traversed by intercellular spaces, which form a connected system, varying in its special character in different cases. Occasionally the median layer of the membrane of the sensitive cells is transformed into a semi-fluid sub- stance, and forms a receptacle for water. The gelatinisation of this layer sometimes fills the spaces with an absorbent colloidal substance. The rapidity with which the sensitive plexi respond to the action of stimuli depends on the presence of this substance, and on its density. The water which fills the intercellular spaces contains various organic sub- * Rep. 66th Meeting Brit. Ass., 1896, pp. 1023-4. Cf. this Journal, 1895, p. 655. t Quart. Journ. Micr. Sci., xxxix. (1897) pp. 387-425 (2 pis. and 1 fig.), j Ber. K. Sachs. Ges. Wiss. Leipzig, June 1st, 1896. See Bot. Centralbl., Ixix. (1897) p. 72. § 11 Naturalista Siciliano, i. (1897) pp. 168-90. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 221 •stances, mostly of the nature of glucose. Sometimes they contain air or some other gas. The sensitive organs chiefly observed were : — The stigma of Martynia , Mimulus, Bignonia, Tecoma , &c. ; the stamens of Portulaca grandiflora, of Opantia amyclea , and other Cactaceae, and of the Berberideae ; the leaves of Mimosa. Positive and Negative Heliotropism.* — Herr F. Oltmanns confirms his previous statement of the existence of au optimum intensity of light for heliotropic curvatures for each species. With the fructification of Phy corny ces he found the curvature to be negative, indifferent, or positive, according to the distance from the source of light ; the former being the case when the distance is least, the latter when it is greatest. Green barley seedlings were more sensitive to light than etiolated ones. The horizontal position of many stems and aerial stolons is the result of purely geotropic causes, often entirely uninfluenced by light. Aerotropism of Roots.f — Dr. A. J. Ewart gives further examples of the aerotropic, or, as he prefers to term it, the oxytropic irritability of the apices of roots. This property is especially well marked in seed- lings of Rcliantlms , Cucurbita , and Pisum ; but it is probably very general. (4) Chemical Changes (including Respiration and Fermentation). Formation of Proteids in Plants.^ — According to Herr T. Kosu- tany, leaves contain a somewhat larger amount of nitrogen by night than by day ; there are then also more amraoniacal salts, and as large a propor- tion of proteids. There is, on the other hand, a larger amount of nitrates in the daytime ; from which it would appear probable that the nitrogen of nitrates is converted into proteids more by night than by day. No asparagin could bo detected in the night, being probably converted into proteids. The nett result is that the raw materials for the production of proteids are absorbed by the plant in greater quantities during the day, but that the final process takes place chiefly at night. Formation of Non-nitrogenous Reserve-Substances in the Almond.§ — From a series of analyses of almonds made at different stages of their ripening, M. Leclerc du Sablon draws the geueral conclusion that, as the amount of oil increases, that of the fatty acids diminishes, the former being apparently formed at the expense of the latter. Glucose is, in the same way, used up in the formation of the reserve food-materials; sac- charose, on the other hand, being found only in the ripe seed ; the same is the case also with the amyloses. Evolution of Heat by Wounded Plants. || — Mr. H. M. Richards gives further results of his experiments on the effects of mechanical injury on potatoes, onion bulbs, and other structures, with a description of the apparatus used to measure the rise in temperature. He finds in- variably a rise in temperature of the adjacent tissue, which attains its * Flora, lxxxiii. (1897) pp. 1-32. Cf. this Journal, 1892, p. 513. t Proo. Liverpool Biol. Soc., x. (189G) pp. 190-3. j Landwirthsch. Versuclis-Stat., xlviii. (1896) pp. 13-33. See Bot. Centralbl., 1890, Beih., p. 488. § Comi-tes Rendus, cxxiii. (1896) pp. 1084-6. |1 Ann. Bot , xi. (1897) pp. 29-63 (2 figs.). Cf. this Journal, ante, p. 145. 222 SUMMARY OF CURRENT RESEARCHES RELATING TO maximum about 24 hours after injury. This maximum was always between two and three times the ordinary plus temperature of the plant. In tubers (potatoes) the effect is local ; while in onion bulbs and other foliar tissues a much greater extent of tissue is affected. Action of Light on Diastase.* * * § — From a series of experiments on the action of light on various solutions containing diastase, Prof. J. B. Green comes to the conclusion that there exists in the leaf and in the various extracts examined, a certain amount of zymogen which is con- verted by the infra-red and the red, orange, and blue rays of the spec- trum into active diastase. The violet and ultra-violet rays, on the other hand, cause a destruction of the diastase, or at least such a change in the configuration of its molecule that it is unable to effect the hydro- lysis of starch. The enzyme is apparently not located in the chloro- phyll grain, but in the protoplasm of the cell. The author advocates the theory that the red colouring of certain leaves is a material help to the translocation of starch in them by screening off the rays which destroy the diastase. There appears also to exist in plants a power of absorbing and utilising the radiant energy of light, sometimes to a considerable extent, without the presence of a chlorophyll apparatus. Fermentative Power.f — Mr. A. J. Brown replies to Duclaux’s criti- cisms of the author’s views on Pasteur’s theory of fermentation. Mr. Brown had brought forward evidence to show that the argument on which Pasteur rested his theory was unsound, and that consequently that theory was untrustworthy. Pasteur had omitted to take time into con- sideration ; and as time enters into and governs the results from which the fermentative'power was calculated, the calculation was therefore erro- neous. The®author would abolish the expression fermentative power or S on the ground that it can never be applied to experimental work with S living organisms, and would retain fermentative activity, — , to express the fermentative powrer of an organism in a unit of time. Alcoholic Fermentation without Yeast.f — It seems probable that Herr E. Buchner has obtained an alcoholic diastase capable of converting sugar into alcohol and carbonic acid without the intervention of yeast. Yeast is pounded up with infusorial earth to break down the cell-walls, and then submitted to hydraulic pressure. In this way is obtained what maybe called a solution of protoplasm, which, when mixed with a 20 to 40 per cent, sugar solution, causes the evolution of gas bubbles in a few minutes, accompanied by the presence of alcohol in the liquid. Technical Mycology.§ — Herr F. Lafar has just brought out the first volume of his handbook on the physiology of fermentation. The work appeals to the chemist, brewer, farmer, and pharmacist. The first volume, with a preface by E. 0. Hansen, deals with Schizomycetes. * Proc. Roy. Soc., Ixi. (1897) pp. 25-8. t Central bl. Bakt. u. Par., 2te Abt., iii. (1897) pp. 33-40. t Bor. Deutsch. Chem. Gesell., xxx. (1897) p. 117. See Aun. Inst. Pasteur, xi. (1897) p. 287. § Jena, 1896. See Centralbl. Bakt. u. Par., 2t0 Abt., iii. (1897) pp. 22-3. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 223> B. CRYPTOGrAMIA. Cryptogamia Vascularia. Leaves of Selaginella.* * * § — Prof. R. J. Harvey Gibson has made a care- ful study of the comparative anatomy of the leaf in the various species of Selaginella. The various forms may be arranged under four principal types, viz.: — (1) the Martensii- type (36 sp.) ; the epiderm is dissimilar on the ligular and aligular surfaces of the leaf ; there is a mesophyll consisting of reticulate parenchyme ; (2) Braunii- type (3 sp.) ; the epiderm of both surfaces consists of elongated sinuous cells, and has a distinct palisade layer as well as reticulate mesophyll; (3) Galeottii- type (9 sp.) ; the epiderm of both surfaces is composed of quite or nearly similar cells with wavy margins, and is much elongated in the long axis of the leaf ; (4) Spinosa-type ( 3 sp.) ; resembles the last, but the leaves are similar and are arranged spirally. S . Lyallii forms am anomalous type. The distribution of the stomates is very variable in the genus, but they are more abundant, as a rule on the aligular surface. The epi- dermal ceils are of three types : — conical, elongated with square ends, and sclerotic warty elongated fibres. The mesophyll varies very greatly in amount and in the form of its cells. The vascular bundle is almost invariably of very simple structure. All the species which have the Martensii-type of leaf belong to the monostelic and tristelic series as regards stem-structure ; while those in which the two epiderms are similar have two laterally placed steles. Apogamous Reproduction in Ferns.j — Mr. W. H. Lang has endea- voured to determine the connection between apogamous reproduction in Ferns and the “cresting” of the frond. With N eplir odium filix-mas there appears to be no such necessary connection ; with Scolopendrium vulgare, Athyrium filix-femina, and Aspidium angular e, the results were more variable. A prolongation of the mid-rib of the prothallium, similar to that described in a variety of Scolopendrium vulgare , was observed also in a variety of Lasirea dilatata ; it also bore sporanges, isolated or collected into sorus-like groups, as well as arehegones and antherids. Opening of the Sporange of Ferns. — Herr C. Steinbrinck J de- scribes the phenomenon of the bursting of the sporange of ferns, by which the spores are scattered, as consisting of three processes, viz. — (1) the opening of the sporange by the folding of the membrane, the annulus first stretching and then bending outwards ; (2) the return of the annulus to nearly its original form ; (3) a final shrinking in consequence of the complete evaporation of the water contained in it. By the use of the same apparatus § as that employed in the case of Mosses, Herr J. Schrodt || shows that the bursting of the sporange cannot be due to the pressure of the air in the intercellular spaces, since it takes place equally under a receiver when the air has been almost entirely pumped out. * Ann. Bot., xi. (1897) pp. 123-55 (1 pi.). Cf. this Journal, 1896, p. 331. t Rep. 66tli Meeting, Brit. Ass., 1896, pp. 1019-20. Cf. this Journal, ante, p. 56. % Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 86-90. Cf. this Journal, 1896, p. 538.. § Vide infra, p. 224. ||. Tom. cit., pp. 100-6. SUMMARY. OF CURRENT RESEARCHES RELATING TO "224 Muscinese. Swelling of the Peristome of Mosses.* * * § — Herr C. Steinbrinck con- tests Biitschli’s theory that the shrinking of the teeth of the peristome of Mosses on drying is due mainly to the contraction of very small cavities which are emptied by the external pressure ; their expansion on imbibition, to the meshes becoming again tilled with water. His con- clusion is based on the fact that the contraction takes place under the air-pump just as it does under the ordinary pressure of the air. He is disposed rather to revert to the micellar theory of Nageli as an explana- tion of the phenomenon. Herr R. Kolkwitz j describes the apparatus employed by Steinbrinck for his experiments. Distribution of Spores in the Splachnaceae.j — Herr N. Brylm calls -attention to the part played by flies in the distribution of the spores of the Splachnese ( SplacJinum , Tetraplodon). These mosses are saprophytes, growing on excrements or on decaying organic matter. The insects lay their eggs in the decaying or foetid organic matter, and are apparently attracted by the bright colour of the hypophyse (apophyse) of the moss, carrying away the spores in large numbers. W itliout this agency ger- mination does not appear to take place. (Edipodium.§ — Herr E. Nyman describes in detail the structure of the oophyte and sporophyte generations of (Edipodium Griffithianum. The cortical parencliyme of the stem is destitute of pores. The central bundle is only rudimentary, and is scarcely differentiated from the cor- tical parencliyme, and can have but little importance for the conduction of water. The rhizoids have sometimes a bulbous swelling at the apex. The great characteristic of the genus, and one quite peculiar to it among Mosses, is the presence of a spongy parencliyme and of stomates in the seta, which thus serves a very important function as an assimilating organ. As regards the systematic position of the genus, the author is disposed to agree with Lindberg in erecting it into a distinct family intermediate •between the Splachnaceae and Tortulacese. Braithwaite’s British Moss-Flora. ||— Tart xvii. of this work com- mences the third and concluding volume, which is to include the Pleuro- carpous Mosses and the Sphagna. The Pleurocarpous Mosses consist of three families, the Hypnacese, Pterygophyllaceae, and Neckeraceae. Of the Hypnaceae the present part treats of the following genera: — Thuidium (6 sp.), Leslcea (3 sp.), Anomodon (3 sp.), and Amblystegium , of which 19 species are included in the present part. Genera and Species of Mosses. t— Prof. C. R. Barnes and Mr. F. Dc F. Heald give a complete Analytic Key to the Genera and Species of North American Musci (including Spliagnacem). Descriptions are appended of * Ber. Deutsch. Bot. Gesell., xiv. (1896) pp. 401-7 ; xv. (1897) pp. 29-33. t Op. cit., xv. (1897) pp. 106-10 (2 figs.). + Biol. Centralbl., xvii. (1897) pp. 48-55 (4 figs.). § ‘ Ona byggnaden ocli utvecklingen af CE 'dipodium G rijfithianum,' Upsala, 1896, 3 pp. and 2 pis. See Bot. Cenlralbl., lxix. (1897) p. 206. || Pt. xvii., 1896, 36 pp. and 6 pis. Cf. Ibis Journal, 1895, p. 457. ^ Bull. IJniv. Wisconsin, No. 5, 1897, x. and 211 pp. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 225 •all the species and varieties published between 1884 and 1896, 603 in number. Dissemination of ddie Spores in Sphagnum.* — Herr S. Nawaschin describes the mode in which the spores escape from the sporange in Sphagnum, which he states to have features unknown elsewhere in the vegetable kingdom. The scattering of the spores is effected by the sudden expansion of the strongly compressed air within the sporange. Differences of tension in the upper parts of the wall of the sporange play a secondary part in the process, bringing about the detachment of the opercuie. Connected with this process is the remarkable abortion of the stomates in the wall of the sporange, there being no actual fissure between the guard-cells. Algae. Corallinaceae. f — Herr F. Hcydrick gives a detailed account of the structure and development of the Corallinaceae, especially of the Melobesieae. Choreonema differs from all the other genera in having no true attachment-disc, the rhizoids penetrating independently into the tissue of the host-plant. In Melobesia the entire thallus usually consists of a layer of rhizoids. The thallus displays no distinct differentiation of tissues, as is the case with the other Florideae. Vegetative propaga- tion takes place in the Melobesieae by growths of various kinds at definite spots in the basal disc ; but this is not the case with the Corallineae. The sexual conceptacles are always dioecious, and consist of cystocarps and antherids. The tetrasporanges are produced (except in Sporolithon ) in non-sexual conceptacles. The author regards the Cryptonemiaceae as the family to which the Corallinaceae arc most nearly allied. The species are arranged under nine genera, viz. : — Choreonema (1 sp.), Melobesia (12 sp.), Mastophora (5 sp.), Litliophyllum (12 sp.), Litho- thamnion (60 sp.), Sporolithon g. n. (1 sp.), besides three genera of Corallineae, Amphiroa, Cheilosporum , and Corallina. A number of new species of Melobesieae are described. Sporolithon g. n. differs from Lithothamnion in the tetrasporanges not being formed in true con- ceptacles, but in layers which permeate the thallus. Structure and Development of Grinnellia.l — Mr. M. A. Brannon has made a detailed study of the life-history of Grinnellia americana belonging to the Delesseriaceae. The cells, both vegetative and reproduc- tive, are connected with one another by protoplasmic pits, or, in the case of those of the procarp, by open pores. The plant is very sensitive to light ; mutilated plants proliferate readily. Plants may originate vegetatively by regeneration of the frond. Pollinoids are developed in enormous numbers by the abstriction of the terminal portion of the apical cells of the antherids. The three-celled procarp is developed from the supporting thallus-cell of the young cystocarp ; its apical cell becomes the carpogone. Fusion of the pollinoid with the trichogyne results in great stimulation to the thallus-cell at the base of the procarp, * Flora, lxxxiii. (1897) pp. 151-9 (1 pi.). t Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 31-70 (1 pi. and 3 figs.). X Ann. Bot., xi. (1897) pp. 1-28 (4 pis.). 226 SUMMARY OF CURRENT RESEARCHES RELATING TO and rapid disintegration of the trichogyne, which is a very evanescent organ, and is often branched. No fusion of cells takes place in the basal region of the cystocarp, as is the case in Gracilaria and other allied genera. The fertilised contents of the carpogone are transferred through the open pores, connecting the procarpic cells with the support- ing thallus-cell, which becomes the central one of the five auxiliary cells. Gloiopeltis.* — The late Prof. F. Schmitz has investigated the struc- ture of this genus of Florideae, and maintains that the alleged genus Endotrichia must be merged in it. G. furcata produces non-sexually bodies closely resembling cystocarps in appearance and structure ; while G. capillaris bears normal sexual cystocarps. From the form and mode of development of the true cystocarps, Gloiopeltis must be placed among the Gloiosiphonacese. Evolution of the Green Algse.f — Prof. R. Chodat, dissenting from many of the views at present current respecting the genetic connection with one another of the various families of Chlorophyceae, makes the following suggestions : — The principal groups may all be traced back to the Palmellaceae, comprising the genera Palmella, Tetraspora , Gloeocystis and Apiocystis. The gelatinous general envelope of the Palmellaceae is produced by the confluence of the special gelatinous cell- walls. Cell- division may take place in three different ways : — irregularly in all direc- tions (Palmella-condition) ; in one plane only ( Te^mspora-condition) ; or tetrahedrally (Gfasocysfo’s-condition). From these three principal con- ditions are derived the three important tendencies which govern the lower Chlorophyceae : — (1) The zoospore-condition (Volvocineae) ; (2) the sporange-condition (Pleurococcoideae) ; (3) the Tetraspora-st&gQ (Ul- vaceae and filamentous green algae). The Volvocinese are derived im- mediately from the unicellular species of Chlamydomonas, to which is nearly related Gonium, where the tetrasporoid-stage is undergone in a motile condition. In Pandorina the earliest stage is the larval condi- tion ; Eudorina and Volvox have a very similar origin. In the Proto- coccoideae the motionless sporange- stage is the most important. All the genera, Oocystis, Nephrocytium, Scenedesmus, Baphidium, &c., can be reduced to globular unicellular colonies, which behave like the sporanges- of Palmella or Dactylococcus. The Pediastreae, Goelastrum , Sorastrum 9. Pedia strum, Hydrodictyon , &c., constitute a parallel group, arranged in. several series. The IJlvaceae and Chaetophoraceae are united with the ancestral forms through Monostroma and Pleurococcus. The latter is a reduced type, existing as a lichen-gonid, and may develope branched filaments, zoosporanges, gametes, or spores. The highest development of the filamentous green algae is reached in the Coleochaeteae. Reproduction among the Phaeosporeae.f — M. C. Sauvageau points out how many lacunae there still are in our knowledge of the different modes of propagation, sexual and non-sexual, in this order of Algae. Especially Berthold’s observations of the conjugation of the zoospores in Ectocarpus siliculosus have not at present been confirmed by any other * Trans. Bot. Soc. Edinburgh, xx. (1896) pp. 554-70. t Ann. Bot., xi. (1897) pp. 97-121. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 227 authority. The author classifies the numerous families in three groups, viz. : — (1) Unilocular sporanges only Laminariacese (except the Chordese), Sporochnacem, Spermatochnacem, Dictyosiphonaceae, Desmarestiaceae, Striariaceae ; 37 genera and 145 species. (2) Pluri- locular sporanges only : — a portion of the Scytosiphonaceae ; 4 genera and 7 species. (3) Both unilocular and plurilocular sporanges : — Lithodermaceae, Balfsiaceae, Stilophoraceae, Chordariaceae, Elachisteaceae, Myriotrichiaceae, Eucoeliaceae (the greater part), Sphacelariaceae, Choris- tocarpaceae, Ectocarpacete, Tilopterideae, Nemodermaceae, Cutleriaceae ; 70 genera and 200 species. The last five families have also other repro- ductive organs, besides ordinary unilocular and plurilocular sporanges. In another paper * the author confirms the observation of Berthold of the conjugation of the zoospores (gametes) formed in the plurilocular zoosporanges of Ectocarpus siliculosus, and gives further details respecting the heterogamous impregnation of E. secundus. E. Lebelii has both antherids and unilocular sporanges, which are probably oogones; the zoospores appear not to have completely lost their sexual character. E. Padinse ( Giffordia Padinse ) possesses antherids, and two kinds of sporange, meiosporanges and megasporanges. The author further calls attention to the fact that in E. tomentosus , and in some other species of the order, the zoospores of the unilocular sporanges are, in opposition to what is generally the case, larger than those of the plurilocular sporanges, and that their mode of germination differs from that of the latter. Epiphyllous Algee.j — Herr W. Schmidle gives a clavis of nine species of Trentepohlia, classified under the two subgenera Eu-Trente- pohlia and Heterothallus. He regards the genus as strongly poly- morphic ; the following new species are described : — T. ellipsicarpa , pinnata , and minima. The author finds an epiphytic species of Scytonema the only one at present known, which he names S. tenuissima , epiphytic on the upper surface of leaves. A new species of Pithophora , P. clavifera , from New Guinea, is also described. Nordstedt’s Index of Desmids.f — This most useful work consists of a Bibliography of the Desmidieae down to the year 1896, and of an alphabetically arranged list of the genera and species. Under each specific name is a chronological series of records of the species and of all the well-marked varieties. Characters of Vaucheria.§— Herr H. Gotz describes the structure and various modes of reproduction in the genus Vaucheria , confirming the observations of previous writers. He adopts Hansgirg’s classification of the species into four groups, viz. : — Corniculatse, Tubuligerae, Pilo- boloideae, and Anomalae ; and describes in detail the characters of the species belonging to three of them as follows : — (1) Tubuliger®, V. orni- * Journ. de Bot. (Morot), x. (1896) pp. 357-67, 388-98 ; xi. (1897) pp. 5-14„ 24-34, 66-76 (12 figs.). Cf. this Journal, 1896, p. 656. f Flora, lxxxiii. (1897) pp. 304-26 (4 figs.). t ‘ Index Desmidiacearum citationibus locupletissimis atque Bibliograpliia, Berlin, 1896, 310 pp. § Flora, lxxxiii. (1897) pp. 88-134 (55 figs.). 228 SUMMARY OF CURRENT RESEARCHES RELATING TO tJiocepJiala, polyspermia , aversa , and dichotoma ; (2) Corniculatse, (a) Ses- siles, V. repens , sessilis, clavata, and pachy derma ; (6) Racemosae, V. hamata, terrestris , uncinata , and racemosa ; (3) Anomaly, F. geminata and . de Bar y ana. Protoplasmic Communications in Volvox.* * * § — Prof. A. Meyer lias studied the nature and purpose of the protoplasmic connections between the cells in Volvox globator, V. aureus , and V. tertius sp. n., the last species characterised by a stratification of the gelatinous membrane, and displaying also different heliotropic properties. Both the optical and the microchemical phenomena indicate that the protoplasmic fila- ments which connect cell with cell are threads of normal cytoplasm displaying no special structure. These threads occur in very much greater numbers in the generative than in the trophic hemisphere. Comparing the protoplasmic communications in Volvox with those which have been detected in other families of the vegetable kingdom, the author regards them of the same nature as those of Angiosperms, as well as those which occur in the animal kingdom, and probably also of the Rhodophyceae, Phaeosporeae, and Schizophyceae. It is probable that such connections exist between all the cells of an individual, and that every individual, both vegetable and animal, is a unit-mass of cytoplasm. Fungi. Influence of Light and of the Substratum on the Development of Fungi. t — M. A. Lendner has experimented on the effect of the access •and withdrawal of light on various Fungi, chiefly Mucorini and Ascomy- ectes, grown on different media. The results differ with different species. All the Mucorini developed sporanges under the influence of light when grown on solid substrata ; in liquid media the results varied with the species. In the case of the conidial forms of the Ascomycetes, conids were always formed under the influence of alternate day and night ; under continuous light, the results varied with the species. The author •regards all the phenomena of heliotropic sensitiveness in Fungi as con- nected simply with nutrition. Parasymbiosis of Fungi.f — Prof. W. Zopf finds fresh confirmation ►of his theory that many of the fungi which grow on lichens are not true parasites, but have a kind of symbiotic relationship to the host, which he terms parasymbiosis , the hypbae of the “ parasite ” enveloping the algal constituent of the liclieD, without inflicting any injury upon it. The observations were made on Bhymbocarpus punctiformis, which attacks Bliizocarpon geographicum, and on Conida punctella and C. rubescens , growing on Diplotomma alboatrum. The hyphae of the parasite were distinguished from those of the lichen by the fact that the latter are ►coloured a beautiful blue by iodine solution, while the former arc not. Effect of Low Temperatures on Mucor Mucedo.§— Prof. R. Fhodat finds that this fungus is not killed by subjection to very low * Bot. Ztg., liv. (1896) ]te Abt., pp. 187-217 (1 pi. and 7 figs.). Gf. this Journal, 1895, p. 662. f Ann. Sci. Nat. (Bot.), iii. (1897) pp. 1-61 (7 figs.). t Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 90-2. Cf. this Journal, ante, p. 151. § Bull. Herb. Boissier, 1896, pp. 8D0-7. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 22^ temperatures ( - 70° to — 110° C. for 36 hours). The mycele continues to develop, though much more slowly than at ordinary temperatures, and normal sporanges are formed. Since respiration is entirely suspended at this temperature, the ordinary theory that respiration is a necessary condition of vegetable life must be abandoned. Protoplasm of Mortierella.* * * § — M. L. Matruchot states that in a species of this genus of Fungi the older parts of the hyphse contain no protoplasm ; or, if there is any, it is granular, without structure, and encloses drops of oil. In the younger parts, on the other hand, the cytoplasm consists of a hyaline portion, not sensitive to staining reagents, penetrated by filaments which are only slightly granular, and which take up stains readily. These threads vary in number from 2 to 10, but do not constitute a network. They vary considerably in thickness, and are the seat of the streaming of the protoplasm, which does not tako place in the denser surrounding hyaloplasm. Characters of Ustilagineae.t — Herr P. Dietel describes the characters of Ustilago IscJisemi, parasitic on Andropogon Ischsemum. It possesses two kinds of hyphae : — the peripheral, which arise in a somewhat thick layer immediately beneath the epiderm of the host-plant, and develop into colourless sterile epidermal cells ; and the fertile, which run at right angles to the former, produce the ustilagospores by successive abstric- tions, and exhaust themselves in the formation of them. The species must belong to the genus Cintractia , if the centripetal order of formation of the spores can be retained as a distinctive generic character. But the author shows that it cannot be so retained. Other species of TJstilago exhibit the same differentiation of hyphse into the envelope-producing and the spore-producing kinds. A similar basipetal formation of clusters of spores occurs in Tolyposporium Junci. Composition of the Mycele of Mould-Fungi. :J — Herr Marschall has investigated the composition of the mycele of typical mould-fungi — Aspergillus niger, Penicilliim glaucum , Mucor stolonifer— and finds the average percentage of proteid substances to be as high as 38, while of cellulose there is only 5*03 per cent., and of substances soluble in alcohol 14*03 per cent. As regards their composition, mould-fungi occupy an intermediate position between bacteria and the higher plants, containing more nitrogenous matter and less carbohydrates than the latter, more carbohydrates and less nitrogenous matter than the former. As contrasted with the spores of Penicillium glaucum , the mycele contains- a larger proportion of proteids, while the spores contain nearly twice as much cellulose, starch, and substances soluble in alcohol. Histology of the Uredineae.§ — M. Sappin-Trouffy has again followed' out carefully the history of development of the Uredinese in the following genera : — Uromyces, Puccinia , Gymnosporangium, Triphragmium, Phragmi- dium, Melampsora , Thecopsora, Cronartium , Endophyllum, Coleosporium y * Comptes Rendus, cxxiii. (1896) pp. 1321-3. t Flora, lxxxiii. (1897) pp. 77-87 (1 pi.). X Arch. f. Hygiene, xxviii. (1896) p. 16. See Bot. Centialbl., 1896, Beili., p. 483. § Le Botaniste (Dangeard), v. (1896) pp. 59-244 (70 figs.''. Cf. this Journal, 1893, p. 342. 230 SUMMARY OF CURRENT RESEARCHES RELATING TO in most cases, in several species of each genus. The following is given as an analytic key to the characters of the genera : — Promycele external. Teleutospores pedicellate, independent. Teleutospores 1-celled ,, 2-celled „ 3-celled „ 4-1 1-celled Teleutospores pedicellate, gelatinous. Teleutospores 2-celled Teleutospores sessile, united into a crust. Teleutospores 1-celled „ 4-celled Teleutospores sessile, confluent in a row Promycele internal (probasid) Pseudo-promycele In all these genera there is great uniformity in the structure of the nucleus and in its behaviour during division, and especially in the process already described under the name of pseudo-fecundation. Uromyces Puccinia Triphragmium PJiragmidium Gymnosporan gium Melampsora Thecopsora Cronartium Coleosporium EndopJiyllum Parasitic Fungi. — Herren M. Woronin and S. Nawaschin * * * § confirm their statement of the specific distinction of Sclerotinia heteroica and S. megalospora. The former produces sclerotcs on Ledum palustre, the latter on Vaccinium uliginosum, and not vice versa . Mr. G. Pirn j describes a new parasitic fungus, Bamularia Lapse, growing on the leaves of the rape. Under the name Schinzia scirpicola , Herr C. Correns J describes a new species parasitic on Scirpus paucijlorus, and distinguished by the sculp- ture of the spore-membrane. Prof. A. S. Hitchcock and Mr. J. B. S. Norton § give a detailed account of the life-history and parasitism of the common smut of Indian corn, Ustilago Zese Mays, together with a complete bibliography and synonymy. They state that infection takes place only through the conids, which germinate in soft growing tissues of the host. A descrip- tion is also given of the less common “head smut” of Indian corn, Ustilago Beiliana . Black-Rot of the Vine. — M. P. Viala || states that, of Guignardia Bidtvellii, the parasitic fungus which causes this decay, pycnids, spermo- gones, peritheces, conidiophores, sclerotes, and chlamydospores are known. The peritheces hibernate, as well as the sclerotes ; chlamydo- spores are formed only under abnormal conditions. The pycnids play the most important part in the reproduction of the fungus. M. A. Prunet f finds that the sclerotes may germinate in the autumn of the year in which they are formed, instead of in the following spring, * Zeitschr. f. Pflanzenkr., vi. (1896) pp. 199-207 (2 pis.). See Bot. Zt g., lv. <1897) 2te Abt., p. 28. Cf. this Journal, 1895, p. 81. t Journ. Bot., xxxv. (1897) pp. 57-8. % Hedwigia, xxxvi. (1897) pp. 37-40 (1 fig.). § Kansas State Agric. Coll. Bull. No. 62, 1896, 44 pp. and 12 pis. |1 Comptes Rendus, cxxiii. (1896) pp. 905-7. 11 Op. cit., cxxiv. (1897) pp. 250-2. 4 ZOOLOGY AND BOTANY, MICBOSCOPY, ETC. 231 as is the case with most sclerotes. A high temperature is not required for their germination, if the air is sufficiently moist. White-Rot of the Vine.* * * § — M. P. Viala has followed out the produc- tion of the hitherto unobserved spermogones and conidiophores, as well as the pycnids and peritheces, of Charrinia Diplodiella , the fungus which produces the white-rot of the vine. “Leprosy” of the Beet. — M. P. Vuilleminf differs altogether from the conclusion of Saccardo and Mattirolo as to the systematic position of the parasitic fungus which produces this disease, and which they name (Edomyces leproides , and place near to Entyloma among the Ustilaginese. The author states the disease to be due to a well-known species of Chytridiacea3, CladocJiytrium pulposum, which infests many species of Chenopodiaceae. In another notej the same author points out the remarkable re- semblance in appearance of the protoplasm of the nutritive apparatus of the Cladochyirium to the striated muscular fibres of animals. Prof. P. Magnus § regards the fungus as belonging to the genus TJrophlyctis (Chytridiaceae). The spores are formed by the conjugation of two cells arising from different filaments. Cell-membrane of Lichens.|| — According to Herr F. Escombe, the membrane of the hyphae of Cetraria islandica , after the extraction of oils, colouring matter, astringent substances, lichenin, &c., consists mainly of an insoluble anhydride of galactose, which the author terms paragalactan. No chitin or cellulose could be detected. The membrane of Peltigera canina contains no cellulose, but apparently a small amount of chitin. The algal cells of Evernia prunastri contain cellulose. Minks’s Lichen-Theory .If — Sig. A. Jatta criticises, on the whole favourably, Minks’s theories of syntrophy and protrophy in lichens. Although restricted in their influence, the phenomena belonging to them are among the most important in the life-history of lichens. Roccellese.** — Herr 0. V. Darbishire gives a monograph of this tribe of the Graphidaceae, a family of fruticose lichens. He classifies them under eight genera, viz. : — Boccella with twelve species ; and seven monotypic genera, Pentagenella g. n., Combea , Schizopelte , DendrograpJia , Boccellaria g. n., Dictyographa g. n., and Ingaderia g. n. The following are the diagnoses of the new genera : — Pentagenella. Thallus fruticulosus, strato corticali distincto con- glutinatis ex hyphis formato transversalibus, strato gonidiali et strato medullari stuppeo ; apothecia lateralia, orbicularia, hypothecio et peri- thecio decolorato, amphithecio thallino gonidia continente, intra hypo- fheeium strato gonidiali instructa, sporis decoloribus ; soralia nulla. * Comptes Rendus, exxiv. (1897) pp. 105-6. Cf. this Journal, 1895, p. 209. t Comptes Rendus, cxxiii. (1896) pp. 758-9 ; Bull. Soc. Bot. France, xliii. (1896) pp. 497-505. % Comptes Rendus, exxiv. (1897) pp. 905-7. § Ann. Bot., xi. (1897) pp. 87-96 (2 pis.). il Zeit. Phys. Chem., xxii. (1896) pp. 288-306. See Journ. Chem. Soc., 1897, Abstr., p. 155. Cf. this Journal, 1896, p. 656. f Bull. Soc. Bot. Ital., 1896, pp. 255-60, 315-21; 1897, pp. 12-18. Cf. this Journal, 1896, p. 439. ** Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 2-10 (1 pi.). 232 SUMMARY OF CURRENT RESEARCHES RELATING TO Boccellaria. Tballus fruticulosus, strato corticali non valde distincto*. cx liyphis formato longitndinalibus conglutinatis, strato mcdullari gonidia continente, infra corticem densissima; apothecia lateralia, orbicularia, liypotbecio et peritbecio fusco-nigro, ampbitbecio tballino nullo, infra liypotbecium gonidia pauca strati medullaris ; sporis decoloribus ; soralia nulla. Dictyographa. Tballus fruticulosus, complanatus, reticulatus, strato corticali nullo distincto, sed ex axibus chondroideis, ex bypbis formatis longitudinalibus conglutinatis constante, strato medullari intra axes longitudinales stuppeo gonidia continente; apotbecia lateralia. orbicu— laria, bypotbecio et peritbecio decolorato, ampbithecio tballino gonidia continente ; sporis fuscescentibus ; soralia nulla. Ingaderia. Tballus fruticulosus, teretus, strato corticali nullo dis- tincto, sed ex axibus cbondroideis, ex liyphis formatis longitudinalibus conglutinatis constante, strato medullari intra axes longitudinales stuppeo, gonidia continente ; apothecia lateralia, elongata, simplicia aut ramosa, bvpothecio et peritbecio fusco-nigro, ampbitbecio tballino nullo, infra hypothecium saepius gonidia pauca, strati medullaris ; sporis decoloribus ; soralia nulla. Latent Life in the TJredineae.* — In the chlorophyll aceous cells of the leaves of wheat infested with Puccinia glumarum , M. J. Eriksson finds exceedingly minute protoplasmic corpuscles, which be regards as the- primordial form in which the protoplasm of the parasite becomes differentiated. He considers this to be a latent or my coplasmatic condition of the fungus in the protoplasm of the host-plant, mingled with the latter in a symbiotic mode of existence which may be termed my coplasm- symbiosis. Kefir.f — Dr. Ed. de Freudenreich, who has been for some time occu- pied in researches relative to the bacteriology of Kefir, finds that this barm owes its properties to four micro-organisms, Sac cliar omyces Kefir, Streptococcus a and b, and Bacillus caucasicus. The yeast, which is com- posed of large oval cells and is easily stainable, ferments maltose and glucose, but not milk. Streptococcus a coagulates milk, and forms lactic acid, while Streptococcus b does not clot milk, though producing abundant acid. B. caucasicus is a small slightly mobile rodlet, which does not clot milk, though it turns it acid and imparts to it an astringent flavour. The main result of the author’s observations is to show that Kefir is a mixed ferment, the effect of which is due to the co-operation or symbiosis of several micro-organisms. The chief part is played by Sacch. Kefir r the streptococci rendering indispensable assistance. What share B. caucasicus has in the process is difficult to say, though it may help to form Kefir-grains. The fact that it is found always, and in consider- able numbers, in Kefir shows that its presence is not accidental. Amylomyces Rouxii and other Starch Ferments.^ — M. J. Sangui- netti, who made a comparative study of Aspergillus oryzse of Koji, of the Mucor alternans Gayoni, and of the Amylomyces Bouxii of Chinese yeast, * Coinptes Rendus, cxxiv. (1897) pp. 475-7. t Ann. de Micrographie, ix. (1897) pp. 1-33; and Centralbl. Bakt. u. Par., 2te Abt., iii. (1897) pp. 47-52, 87-95, 135-41 (2 figs.). Of. this Journal, 1889, p. 99j X Ann. Inst. Pasteur, xi. (1897) pp. 264-76. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 233 lias found that these three Mucedineae possess a very energetic sacchari- fying power : that of A. Oryzse being the most intense, Amylomyces next, and Mncor alternans last. In all the media examined, Amylomyces left more hydrates of carbon untransformed than the other two, owing to its combustive power being much less. Amylomyces possesses a more •considerable fermentative power than the other two, owing to its feebler combustive properties ; and it is the only one useful in practice for indus- trial purposes, either for direct fermentation of amylaceous substances or for the utilisation of distillery residue. The three Mucedineae were cul- tivated at 30° C., and in the following media : — (1) sterilised sucrase-free yeast-water, to which were added starch, dextrin, saccharose ; (2) brewery wort; (3) distillery wort; (4) distillery “ vinasse,” i.e. the residue after alcoholic fermentation. Pathogenic Action of Blastomycetes.* — Prof. F. Sanfelice, in a further communication, supports his contention that the bodies found in certain neoplasms, and described by numerous authors as Sporozoa, are nothing else than Blastomycetes. The results of inoculation with cul- tures of Sciccliaromyces neof ormans on Mus musculus, white rats, rabbits, •dogs, and fowls, were confirmatory of the author’s view. Tumours were developed not only at the primary injection site, but were found also as secondary deposits. S. neof or mans was found in the primary and secondary deposits ; the Blastomycetes were usually free and not intra- cellular. In one dog the tumours were epitheliomatous. Pathogenesis of the Soor Fungus.f — Dr. M. Steiner has shown by experiments on rabbits, that the Soor fungus may be pathogenic to animals. By injecting suspensions of pure cultures of the Soor fungus in •0* 6 per cent, salt solution, into the ear or jugular vein, a general my- cosis was induced, but not in all cases. The dose injected was 1 ccm. per kilogram of animal. The fungus was found in pure cultivation in every organ and part of the body where the injection was successful. The foci where the fungus was deposited were surrounded by a small- celled infiltration. Mycorhiza of Corallorhiza.J — Mr. A. Y. Jennings describes the mycorhiza which infests the parenchymatous tissue of the rhizome of {Jorallorliiza innala, and spreads out for a long distance into the surround- ing soil. The hyphae of the mycorhiza penetrate the epidermal cells of the host through long tufts of hairs, which serve for their collection and transmission. The mycorhiza appears to belong to an agaric, probably a Tricholoma or Clitocybe. Protophyta. a. Schizopiiyceee. Auxospores of Diatoms.§ — Herr Gr. Karsten describes the mode of “formation of the auxospores in Dickiea crucigera , Nitzschia longissima, * Annali d’lgiene Sperimeutalc, vi. (1896) p. 265. See Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 158-9. Cf. this Journal, 1896, p. 552. t Centralbl. Bakt. u. Par., xxi. (1897) pp. 385-8 (1 pi.). X Bep. 66th Meeting Brit. Ass., 1S96, pp. 1011-2. § Flora, lxxxiii. (1897) pp. 33-53, 203-22 (3 pis.). Cf. this Journal, 1896, p. 662 ; ■ante, p. 62. 1897 R 234 SUMMARY OF CURRENT RESEARCHES RELATING TO Melosira Borreri , and Gallionella nummuloides. In the first-named species the process differs from that in other Naviculeae in that the two conjugating individuals always place themselves with their valve- sides next one another. Gallionella exhibits a departure from Pfitzer’s statement that in the Melosirese each of the cells which goes to the for- mation of an auxospore has first been formed by division. In this instance the nucleus passes from the older into the younger cell. The mode of formation of the auxospores in the Melosirese coincides with that in Synedra affinis, with only unimportant differences. It is, in fact, a modification of the process of cell-division. In Synedra affinis two auxospores are formed from each cell by longitudinal division. Each auxospore has two well-developed nuclei,, each with a large nucleole. In Brebissonia Bceclcii the two conjugating diatoms are always so placed that their girdle-bands lie side by side or one on the other. In Achnanthes brevipes two mother-cells take part in the formation of each auxospore. The author believes that in all cases- the formation of an auxospore is but a modified form of longitudinal division, conjugation of the daughter-cells of two individuals taking the place of the conjugation of nuclei within one and the same individual. He argues in favour of the near relationship of the Diatomaceae to the Desmidiem. The author distinguishes two types of auxospore-formation in dia- toms : — (1) That of the Melosireac, in which the auxospores are formed by the agency of a single cell-division, usually greatly reduced ; (2) that of the Naviculeae, Cymbelleae, Achnantheae, and Fragilarieac, in which a double cell-division takes place, the second division being often reduced. He derives the conclusion that originally diatoms multiplied only by division, and that the formation of auxospores is a mode of increase and rejuvenescence derived from a purely vegetative multiplication in two different ways. Structure, Division, and Movements of Diatoms.* — Herr R. Lauter- born publishes a detailed treatise on the structure of the protoplasm in diatoms, especially in reference to the division of the nucleus and of the cell. The “ red corpuscles ” are regarded as reserve-substances employed by the cell for building up new matter, as, e.g., in the process of cell- division. The centrosome has been observed in other species besides- the one in which it was originally detected, viz. in Surirella splendida,. S. biseriata, Pinmdaria major, and P. nobilis. The division of the nucleus and of the cell are described in detail in several species, especially in Surirella calcarata, where the process attains a great degree of com- plexity. The paper is accompanied by a careful bibliography. Dr. 0. Miillerf criticises in several points Lauterborn’s explanation of the causes of the movements of diatoms. He regards the movements a& taking place by means of currents of a mucilaginous substance project- ing through the raphe on to the outer cell- wall. He has never seen any trace of the threads described by Lauterborn as springing from the central node. * * Unters. iib. Bau, Kernlheilung, u. Bewegung d. Diatomeen,’ Leipzig, 189G,. 165 pp., 10 pis., and 2 figs. See Bull. Soc. Beige de Microscopic, xxi. (1897) p. 27. Cf. this Journal, 1894, p. 606. t Ber. Deutseli. Bot. Gesell., xv. (1897) pp. 70-8. • ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 235 Van Henrck’s Synopsis of the Diatomacese.* * * § — An English trans- lation of this important work has appeared in advance of the original treatise in French. It makes up a volume of nearly 600 pp., illustrated by 35 pis. containing 917 figs., besides 300 inserted in the text. In addition to the systematic portion, it contains a full account of the structure, movements, multiplication, and reproduction of diatoms. The author regards it as an established fact that a substance passes from the cell-cavity through canals or pores in the silicified coat. Schmidt’s ‘Atlas der Diatomaceen-Kunde.’ — Hefts 52, 53 of this magnificent work, just published, contain 8 plates, Nos. 205-212, chiefly devoted to various species of the genera Surirella, Plagiogramma, and Navicula. Structure of Cyanophyceae.f — Prof. E. Zacharias confirms his pre- vious conclusion that the central body of the Cyanophycese differs in important points from the nucleus of other organisms. He now consi- ders it doubtful whether the central substance contains nuclein like the chromosomes. In Gloiotrichia pisum it is probable that the central body of the spore and of the cells immediately above it contains glycogen. The cell-protoplasm contains, at different stages, varying quantities of granules, which are chemically different from the central substance. The cell-division takes place without showing karyokinetic processes,, the disposition of the constituents of the central body being variable and without rule. The granules in the cell-protoplasm appear to increase in size and number when the cells are able to assimilate carbon. Development of Sphaerozyga.J — In addition to the ordinary Nostoc- form of Sphserozyga oscillarioides, Herr W. Schmidle finds, growing on Vaucheria sessilis , a form in which the cells which usually develope into resting-spores, remain in a purely vegetative condition, or become disor- ganised. Other cells, on the other hand, in the middle of the filament,, grow to a large size, and in these appear a number of very minute cells or spores. These do not swarm out, as described by Zukal in other Cyanophyceae, but escape through the gradual gelatinisation of the mem- brane of the mother-cell. In this condition the Sphserozyga resembles a colony of Aphanotliece. From other cells filaments arise which produce liormogones, and which are indistinguishable from a Calothrix. All intermediate stages occur between this and the Aphanothece-form. £. Schizomycetes. New Genus of Schizomycetes with Longitudinal Fission.§ — Mr. A. V. Jennings records the existence of a Schizomycete, Astrohacter Jonesii, found by Mr. A. C. Jones in fresh water. Its chief characteristic is that it divides longitudinally, thus eventually producing a distinctly stellate arrangement. Simple rod-like forms were observed, but more frequently V- or Y-shaped cells, resulting from longitudinal fission. After division the new segments become more and more widely separated * ‘ A Treatise on the Diatomacese,’ by Dr. H. Van Heurck, translated by W. E. Baxter, 1896. 8ee Bull. Soc. Beige de Microscopie, xxi. (1897) p. 24. f Rep. 66th Meeting Brit. Ass., 1896, pp. 1021-2. Cf. this Journal, ante , p. 156. X Ber. Deutsch. Bot. GeselL, xiv. (1896) pp. 393-401 (1 pi.). § Rep. 66th Meeting Brit. Ass., 1896, p. 1012. R 2 236 SUMMARY OF CURRENT RESEARCHES RELATING TO at tlie ends, till regular three- or four-rayed stars (and later on six- or eight-rayed) were produced. There was no tendency to the pear-shaped swelling seen in Pasteuria ramosa, and no spores were noticed. Emulsion and Sediment Figures produced by Motile Bacteria.* — Prof. W. Beijerinek states that motile bacteria, when occurring in great numbers in thin layers of a nutrient solution, form, after being allowed to rest for a few minutes, characteristic accumulations. These accumulations are either columnar in shape and run up and down right through the whole thickness of the fluid, or are flat and lie at the bottom of the vessel. In either case the groups or accumulations are sharply defined, and are separated from one another by fluid poor in bacteria, or devoid of them. The columnar groups are called emulsion-, the flat- groups sediment-figures. The former most commonly originate in thick fluid media, such as liquefied gelatin ; the latter in thin liquid media, such as bouillon. In any case the figures are the result of the specific properties of the bacteria, though all mobile bacteria are not equally suit- able for the production of emulsion-figures. The emulsion-figures are probably caused by local currents ; in the interspaces fluid saturated with carbonic acid ascends, while within the columns a liquid medium saturated with oxygen descends. The author, after describing Bacterium termo, proceeds to discuss the changes caused by currents, by dilution, and by chemotaxis. In the course of his remarks the author introduces a new word, “ tonotaxis,” or sensitiveness to osmotic variations, and con- cludes by describing the influence of an oil-drop. Kitre-Fungi.| — In their reply to Winogradsky, who asserted that Ihc results obtained by Prof. A. Stutzcr and Heir K. Ilartleb were due to unskilful manipulation, these writers give a short retrospect of the points at issue, and then clearly state their own view, which is to the effect that nitrification is a transitory function of a definite organism, which under certain conditions can thrive on organic nutrient media. The proof of this is promised later. Meanwhile they mention an inter- esting observation which tends to support their view. A pure culture of the nitrate organism was transferred to nutrient fluid, the source of nitrogen being sodium nitrite. Through the vessels a current of air was transmitted. For the first flask the air w’as filtered through cotton- wool ; for the second it was passed through a thick layer of strong caustic soda solution ; so that, in the one flask, carbonic acid was present, in the other not. In the latter vessel had been placed a small quantity of glycerin. The vessels were kept in the dark at a temperature of 25°— 30° C., and after a lapse of about 12 days the microbes in the first flask had produced nitrate and had undergone no morphological change. In the second flask there was no nitrate, the medium was turbid and con- tained numerous rodlets and cocci, and also a raycele similar to that which had so frequently spoilt the aqueous nutrient media of previous experiments. Denitrifying Bacteria and the Loss of Nitrogen caused by them.t — Herren K. Burri and A. Stutzer isolated from horse-dung two bacteria * Centralbl. Bakt. u. Par., 2te Abt., iii. (1807) pp. 1-6, 40-7 (1 fig. and 1 pi.). t Op. cit., ii. (1897) pp. 6-9, 54-7. Cf. this Journal, ante, p. 145. X Ann. Agroii., xxii. (1896) pp. 491-4. See Journ. Cliem. Soc., 1897, Abstr., p. 114. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 237 which together, but not singly, dccompos3 nitrites with liberation of free nitrogen. One was identified as B. coli commune , whilst the new one was designated B. denitrificans i. Another variety, B. denitrijicans ii., which liberates nitrogen from nitrates and nitrites, was isolated from old straw. This microbe throve in artificial solutions as well as in nitrate- broth, and destroyed the nitrate in the same length of time. B. coli with B. denit . i. caused no turbidity in the artificial solution in a week, and did not decompose the nitrate in the least. With B. coli and B. denit. i., and also with B. denit . ii., the destruction of nitrate is checked when the amount of nitrate exceeds 0 * 5-0 • 6 per cent., owing to excessive alkalinity. Phosphoric acid (0*06-0 *07 per cent.) checked the fermen- tation by B. coli and B. denit. i. ; whilst B. denit. ii. was active with 0*14 per cent, of acid. B. denit. i. and B. coli reduce nitrates com- pletely in the absence of oxygen, but without evolution of nitrogen, the nitrate being converted into nitrite. But with even a limited access of air these organisms will produce free nitrogen. B. denit. ii. decom- poses nitrates normally in complete absence of air ; whilst with aeration the fermentation is hindered or prevented. Inoculation of Nodule-Bacteria in different Host-Species.* — Herren F. Nobbe and L. Hiltner have carried on a series of experiments on the inoculation of bacteria from the root-tubercles of one to those of a dif- ferent species. The results were, as a rule, negative, the inoculation being certain only from one plant to another of the same species. An exception is afforded by the Yicieae, where inoculation, without essen- tially lessened effect, is possible from one species to another. The effect of inoculation was increased vigour and development cf the plant ; in- creased production of flower and fruit was observed, especially in the case of peas and red clover. The authors state that root-tubercles have no essential influence on the growth above ground, so long as the soil contains sufficient nitrogen. Bacterial Diseases of Plants.f — Mr. E. F. Smith gives a resume of the diseases of plants ascertained to be due primarily to the attacks of Schizomycetes, arranged according to the host-plant which they attack. Five of these belong to the beet aud two to the hyacinth. The bacterial disease of the potato is referred to an unnamed organism (Kramer’s potato bacillus), which differs from both Bacillus amylobacter and B. butyricus in not being anaerobic. Bacteriosis of Celery. :J — Dr. Ugo Brizi describes a disease which affected the celery plants in North Italy in the past year. The parts of the plant (Apium graveolens) most attacked were the stems, which first showed the malady, presenting yellow to brownish spots, which after- wards ulcerated. Microscopical examination showed the presence of a large bacillus ( Bacterium Apii), which was easily cultivated on various media. Bacterial Disease of the Squash-Bug.§ — Mr. B. M. Duggar found that squash-bugs ( Anasa tristis), kept for laboratory purposes, died in * Landwirth. Vers.-Stat., xlvii. (1896) pp. 257-68. See Journ. Chem. Soc., 1897, Abstr., p. 61. f American Naturalist, xxx. (1896) pp. 626-43, 716-30, 796-804, 912-24; xxxi. (1897) pp. 34-41, 123-38. % Atti R. Accad. Lincei, vi. (1897) pp. 227-34. § Bull. Illinois State Laboratory Nat. Hist , iv. (1896) pp. 340-79 (2 pis.). 238 SUMMARY OF CURRENT RESEARCHES RELATING TO considerable numbers ; and on microscopical examination discovered a bacillus to which the mortality was due. This organism ( Bacillus ento- motoxicon) occurs in the blood and tissues of the insect. It is 1 • 2-1 • 8 ^ long by 0 • 6-0 • 8 /x broad ; it is motile, does not form spores, and stains well with most anilin dyes. It is aerobic, and potentially anaerobic. The colonies on agar are white, with fanlike radiations. Gelatin is liquefied. Milk is rapidly coagulated, with a highly offensive odour. It grows well at room temperature, and is killed by exposure to high temperatures. The infected insect becomes sluggish, swells, and after death rapidly liquefies. The toxin is lethal to many species of insect. The disease is easily communicated to healthy squash-bugs by contact with the fluids of infected insects, or with agar cultures. The young insects are easily infected, the older ones being more resistant, and the larvae apparently quite refractory. Leptothrix placoides.* * * § — Dr. A. R. v. Dobrzyniecki describes a species of Leptothrix ( L . placoides) which was isolated from an old tooth stop- ping. It consists of long delicate structureless threads, which, when stained, seem to be made up of chains of rodlets, and in which spore-like bodies were observed. The Leptothrix-iodine reaction (iodopotassic iodide acidulated with lactic acid) was successful. The organism was cul livable on agar, blood-serum, and gelatin, the latter being liquefied, but not in bouillon or on potato. The colonies are white, firm, and discoid. Ciadothrix odorifera.f — Herr Rullmann regards this organism, to which the odour of freshly turned-up soil is largely due, as a variety of (7. dichotoma. Silkworm Microbe.* — Sig. L. Macchiati gives reasons for identify- ing the microbe which has been named Streptococcus Pastorianus, the cause of the flaccid condition of silkworms, with the earlier described S. Bombycis. Rejuvenescence of Effete Pebrine Corpuscles.§ — It is well known, says M. M. Krassilschtchik, that pebrine corpuscles, when old, lose the power of exciting the disease in silkworms. Their activity and virulence may, however, be restored if they are swallowed by the common sparrow. Infected moths kept over from the preceding year are pounded up in a mortar with a little water. Pieces of bread soaked with tbe mixture are given to sparrows. On the third day the excrement is found to con- tain active pebrine germs. Silkworms fed on mulberry leaves contami- nated with the fresh excrement acquire pebrine. On the other hand, dried excrement does not excite pebrine ( Microsporidium ), but sets up flacherie ( Streptococcus Pastorianus) and grasserie ( Micrococcus larda- rius ), or even a mixed infection of the twro diseases. It would seem therefore that birds contribute to the propagation of pebrine, their intervention being indispensable for rejuvenating inactive corpuscles. Some of the sparrows fed on the infected moths died, the control birds remaining quite healthy. * Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 225-9 (4 figs.). t Op. cit., 21e Abt., ii. (1896) pp. 116-7. % Bull. Soc. Bot. Ital., 1896, pp. 292-7. § Comptes Rendus, cxxiii. (1896) pp. 358-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 239 Bactericidal Action of Tannin.* * * § — Prof. G. Goegg records a large series of elaborate experiments with tannins of various derivation on five microbes, for the purpose of testing their bactericidal properties. The microbes were B. anthracis, B. pyocyaneus , B. coli. com., B. prodigiosus, St. aureus ; and the tannins, aspidospertannic, coffee-tannic, catechu- tannic, gallic, kino-tannic, rhatany-tannic, and tannic acids. Extract of rkatany and kino resin were also used to determine the difference between the pure tannins and preparations containing tannin. The author’s work clearly establishes that officinal tannin is less energetic than other tannins termed physiological. Aspidospertannic acid, for example, is far more bactericidal than officinal tannin. Hence there is some relation between the bactericidal action and the remarkable tan- ning action which Quebracho Colorado (from which aspidospertannic acid is obtained) has in the leather industry. Kino-tannic acid acts more powerfully than the kinos themselves ; and rhatany-tannic acid exerts a considerable bactericidal action on B. pyo- cyaneus and St. py. aureus. Spore-forming bacteria appear to be little sensitive to the action of tannin ; on the other hand, St. py. aureus is extremely so. Mechanism of Immunity imparted by Anti-coagulating Sub- stances.f — MM. Bose and Delezenne made experiments relative to the immunity imparted by anti-coagulating substances. They found that leech extract or pepton, when injected into the blood, is able to produce certain modifications which increase the defensive powers of the organ- ism against infectious agents. These modifications are characterised by a remarkable increase in the vitality and phagocytic properties of the white corpuscles, and by augmentation of the bactericidal power of the blood. The intravenous injection of the anti-coagulating substances into rabbits and dogs 15-45 minutes before the injection of coli bacillus or of Streptococcus , is able to confer on these animals a real immunity, and even to impart an action absolutely inhibitory against experimental infection. Bacteriology of Plague.J — Herr Kolle states that the pus in the bubos contains bacilli with rounded ends. Both ends stain deeply, the central portion hardly staining at all. This bacillus is also found in the blood and in the spleen. It does not stain by Gram’s method. On agar the colonies are whitish grey ; on gelatin, which is not liquefied, they are light brown and finely granular. In grape-sugar bouillon the organism thrives. No spore-formation was observed. The cultures are killed in a few minutes at 100°, and at 58° in a few hours. iEtiology of Dysentery .§ — Dr. W. Janowski concludes, from an exhaustive review of 84 works on dysentery by different writers, that this disease is the result of a co-operation of several parasites, and is not due to the pathogenic action of a single microbe. Two varieties of •dysentery are distinguished, the ordinary malady caused by the associ- * Ann. de Micrographie, ix. (1897) pp. 49-144. t Comptes Rendus, cxxiii. (1896) pp. 500-3. X Deutsch. Med. Woekenschr., March 4, 1897. See Brit. Med. Journ., Epit., April 3, 1897, p. 56. § Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 88-100, 151-8, 194-202, 234-55. 240 SUMMARY OF CURRENT RESEARCHES RELATING TO ated action of bacteria, and the tropical, wLich has certain peculiarities in its clinical and anatomical aspects. This form is probably excited by the co-operation of a definite species of amoeba with bacteria. Chicken-Cholera in Australia.* * * § — Mr. C. J. Pound reports the dis- covery of chicken-cholera in Australia. The birds (ducks and fowls) had died with the symptoms and phenomena of Septicsemia lisemorriiagica u The blood was fatal in about 14 hours to rabbits and mice. The bio- logical characters of the isolated organism are, that it docs not spore, is non-motile, is aerobic, the colonies on gelatin at 70° F. are at first white and spherical, afterwards becoming yellowish and irregular in shape. On potato, at incubation temperature, the growth is yellowish and waxy looking ; growth in beef-broth is rapid, the medium becoming turbid,. As the organism was found to be so fatal to rabbits, the author advised that cultures should be used for the purpose of destroying these rodents ; and the report to the Government of Queensland mainly deals with the methods of cultivating the microbe and of employing the disease for the destruction of rabbits. It also deals with the transmissibility of the disease, the practical working of the scheme, and contains reports of a large number of experiments with chicken-cholera on domesticated and wild birds and animals. Microbial Origin of Baldness.} — Dr. L. Wickham describes how Sabouraud, who has been occupied with the subject for three years, dis- covered that alopecia areata and seborrhcea are probably due to the: action of the same organism, a bacillus, which, cultivated on acid gly - cerinised gelose, gives brick-red colonies. The mechanism of the process appears to be that the bacillus invades the hair-follicle, exciting sebor- rhcea , in consequence of which the papilla atrophies, and, pari passu, the hair. Experiments made with the toxin of the seborrhcea bacillus, obtained by filtration from cultures in liquid media, showed conclusively its specific action. Differentiation of Diphtheria from Pseudo-Diphtheria Bacilli.} — Dr. L. de Martini, who has been trying to obtain a practical test for differentiating the true diphtheria bacillus from the organism which so closely resembles it, started with two types of non-virulent bacilli, one of which (a) acidified neutral bouillon, while the other (b) rendered this medium distinctly alkaline, and that within 24 hours. On ordinary liquid serum, bacillus a grew well, but in liquid diphtheria serum, not at all. Bacillus b did badly in both. Both a and b, and also virulent diphtheria bacilli, grew well on coagulated ordinary and diphtheria serums at 70°. The author infers from the foregoing that there is the greatest probability that the type a was a degenerated form of the diph- theria bacillus, and that type b must be regarded as a pseudo-diphtheria bacillus. Spirillum Obermeieri and Relapsing Fever Blood.§— Dr. J. Tictin records some observations he made with the blood of relapsing fever- patients. Attempts were made to keep the spirillous blood at room tem- * ‘ Report relating to the Microbes of Chicken-Cholera,’ Queensland, 1897, 22 pp. and 3 figs. f Brit. Med. Journ., 1897, i. pp. 1028-30. X Centralbl. Bakt. u. Par., l,e Abt , xxi. (1S97) pp. 87-S. § Tom. cit., pp. 179-86. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 241 perature in glass vessels. Under these conditions the movements of the spirilla soon ceased, the microbes died, their bodies degenerated, and finally disappeared. Cover-glass preparations made from such blood showed Spiroclisetse in leucocytes. As phagocytosis was not observed in the blood of patients or of apes suffering from relapsing fever, the author concludes that leucocytes can only attack spirilla successfully when the latter are enfeebled. Observations on splenectomised apes are alluded to, but the results are not yet published. An interesting observation made by the author, namely, that spirilla are demonstrable within the bodies of bugs, led to the suggestion that the disease might be transferred through the agency of these insects. Bacillus forming Butyric Acid from Glycerol.* * * § — Dr. 0. Emmer- ling isolated from cow-dung by Fritz’s method a bacillus which is named B. boocopricus. It is very similar to B. subtilis, and grows well on gelatin. With beef-broth it does not form indol. With glycerol at 36°, in the presence of calcium carbonate, methylic alcohol, acetic acid, butyric acid, and traces of formic and succinic acids, are produced. From grape-sugar, ethylic alcohol and lactic acid are produced. Pigment-forming Micrococcus from Red Milk.j — Dr. G. Keferstein describes a coccus which imparts a reddish hue to milk. The colour first appears five or six days after inoculation, and attains its maximum degree in about two weeks. The coccus grows slowly, but best on agar at 22° C. The formation of the pigment is dependent on the presence of air. On gelatin the colonies are small and rose-coloured, afterwards deepening in hue ; the medium is not liquefied. The cocci have no special arrangement, and are easily stained by the usual methods. The coccus is not pathogenic to mice, and is resistant to dry heat. Influence of Carbonic Acid on the Growth of, and Toxin-formation, by Diphtheria Bacilli.}: — it is usually held that bacteria thrive best on faintly alkaline media ; the medium, however, is only alkaline at first ; for as soon as germination begins the alkalinity diminishes, and finally gives, place to acidity. According to the experiments made with diphtheria, bacilli by Herr N. P. Schierbeck, an alkaline reaction, even of minimum degree, is positively harmful, while an acid reaction of the medium exerts a favourable influence, provided that there be free carbonic acid present. When C02 is absent, or when the reaction of the medium is neutral, the author found that bacterial development was far less than with C02 and an acid reaction. Under the influence of C02 toxin forma- tion appeared to be more rapid, and the contradictory results obtained' by different observers relative to toxin formation under the influence of currents of air appear to be explained by the author’s experiments. Pathogenic Bacillus found in Ice-Creams and Cheese.§ — MM. Y. C. Vaughan and G. D. Perkins found in ice-cream and cheese a bacillus which grows aerobically and anaerobically. Numerous persons who had * Ber. Deutsch. Bot. Geaell., xxix. (1896) pp. 2726-7. See Journ. Chera. Soc.r 1897, Abstr., p. 113. f Centralbl. Bakt. u. Par , lte Abt., xxi. (1897) pp. 177-9. X Arch. f. Hygiene, xxvii. No. 4. See Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 165-6.' § Arch. f. Hygiene, xxvii. No. 4. See Centralbl. Bakt. u. Par., 2‘e Abt., ii.. (1896) pp. 799-800. 242 SUMMARY OF CURRENT RESEARCHES RELATING TO partaken of the creams and of the cheese were seized with vomiting and diarrhoea and other symptoms of toxin poisoning. Though greatly resem- bling B. coli communis , it is distinguished therefrom by the absence of the indol reaction ; it coagulates milk more quickly ; the agreeable ethereal odour of milk cultures of the ice-cream bacillus is not developed by the coli bacillus in the same medium ; on carrots, onions, and some other vegetables the ice-cream bacillus grows quickly and develops an acid smell. Milk stained with rosolic acid is more quickly decolorised by this bacillus than by B. coli com . The ice-cream bacillus is patho- genic to guinea-pigs, rabbits, cats, dogs, mice, and rats, and its virulence is increased by passage through animals. The toxin was not isolated. Spontaneous Coagulation of Milk.* — Dr. G. Deichmann states that he has discovered a coccus which, from frequent observations, he believes to be one of the causes of the spontaneous souring of milk. In some samples it is quite as numerous as Bacterium lactis acidi. This discovery will serve to explain the presence of optically inactive lactic acid ; for, while B. lactis acidi produces recto-lactic, the coccus forms lsevo-lactic acid, so that by a combination of the two latter the inactive acid results. Though the two bacteria are not unlike in form and size, they are dis- tinguished, not only by the difference in their products, but also by the fact that the coccus forms gas. Agglutination Phenomenon in Glanders.f — Mr. A. G. R. Foulerton states that agglutination of the glanders bacillus can be brought about by contact with a serum, (1) from a case of active infection by the glanders bacillus, (2) from active infection of typhoid bacillus, (3) from a horse immunised against diphtheria. No such action is manifested by either normal human or equine serums. On reversing the experiments, it was found that a certain though decidedly less active agglutination of the typhoid bacillus was caused by both antidiplitheritic and glanders serums. Thus the serum reaction in glanders as an aid to clinical diagnosis is extremely doubtful ; and the foregoing results suggest that the absolute specificity of serum agglutination in different diseases has yet to be proved. Agglutination Phenomenon and the Cholera Vibrio.^ — From a series of experiments made with the cholera vibrio, Dr. A. Taurelli Salimbeni finds that the agglutination, as far at least as this microbe is concerned, is produced exclusively outside the organism. Agglutination was not observed either in the subcutaneous tissue or in the peritoneal sac of animals which had been actively or passively immunised. In another series, in which the serum and vibrios were mixed together in vitro and in vacuo, it was found that the tubes remained unchanged, while in control tubes in contact with air the ordinary agglutination took place. Biological Status of Bacillus Tuberculosis.§ — Mr. A. C. Jones sug- gests that the so-called tubercle bacillus is really a stage in the life- history of some higher form of fungus with a definite mycelial growth, and that it would be more appropriately designated Tuber cidomyces. * Centralbl. Bakt. u. Par., 2te Abt., ii. (1896) pp. 777-80. t Lancet, 1897, i. p. 1201. X Anu. Inst. Pasteur, xi. (1897) pp. 277-86. § Rep. 66tli Meeting Brit. Ass., 1896, pp. 1015-6. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 243 This view is supported by the fact that incipient branches may be observed not unfrequently in samples from sputa or cavity contents. More rarely there are definite threads or hyphae, which exhibit true branching, and often contain one or two spores, forming oval, highly refracting, deeply stained swellings on the course of the filaments. These spores have a close resemblance to chlamydospores, and are not to be confounded with the unstained intervals in the common rodlet, and described by Koch and others as spores. These spaces are really the result of plasmolysis. Old cultures, examined as sections, do not show separated rodlike forms isolated from one another, and lying at all angles, but strands of parallel filaments frequently exhibiting dichoto- mous branching. Influence of certain Yeasts in Destroying the Vitality of the Typhoid and Colon Bacilli.* — Dr. J. S. Billings and Dr. Adelaide W. Beckham made a series of researches upon the influence of light, of desiccation, and of the products of certain micro-organisms, upon the vitality of the typhoid and colon bacilli. Insolation of plate cultures was found to destroy all the germs in from three to six hours, while diffuse daylight, gaslight, or electric light, produced little or no effect. Bouillon tubes inclosed in coloured glass tubes showed an increase up to the eighteenth day, after which the numbers began to decrease. Inso- lation not only affects pathogenic bacteria, but also the culture media, so that they become less capable of supporting the growth of these organisms after periods of insolation varying from 1 to 60 days. Desiccation experiments showed that these organisms retained their vitality for at least five months. Further researches made to ascertain the influence of the common water bacteria or their products upon the vitality of the typhoid and colon bacilli showed that this influence was practically nil. Bacillus of Friedlaender in Tonsillitis and Pharyngitis.f — Mr. W. C. C. Pakes has found the pneumobacillus in five cases out of 500 examinations of patients suffering from tonsillitis and pharyngitis. The morphological characters were, non-motility, polymorphism, decolora- tion by Gram’s method, presence of a capsule. Cultures on gelatin, agar, blood-serum, and in bouillon were characteristic ; the gelatin was not liquefied, gas production in glucose-gelatin, formation of acid in lactose bouillon, coagulation of milk with acid reaction, were exhibited. Mice inoculated with cultures died, the typical bacillus being found in the heart-blood and in the spleen. Bacterium coli anindolicum and Bacterium coli anaerogenes.J — Herr W. Lembke reports on two bacteria isolated from dog’s faeces, which, in their appearance and growth-characters, resembled B. coli commune , and differed therefrom in that the one forms no indol, and the other produces no gas in media containing grape-sugar. The growth of the two differed on gelatin, potato, and in bouillon. Their length was 0*002 mm. and their breadth 0*001 mm. They were mostly in pairs, * Smithsonian Report for 1894 (1896) pp. 451-8. t Brit. Med. Journ., 1897, i. p. 715. j Arch. f. Hygiene, xxvii. pt. 4. See Centralbl. Bakt. u. Par., lte Abt., xxi. <1897) pp. 281-2. 214 HUMilARY OF CURRENT RESEARCHES RELATING TO though not unfrequently several were linked together. B. anindolicunv is motile and flagellated, while B. anaerogenes is motionless and devoid of flagella. B. coli anindolicum gives in bouillon with potassium nitrite and strong sulphuric acid a red colour which can be extracted with amyl alcohol. It ferments grape and milk sugars with formation of gas- and acid. B. coli anaerogenes also ferments both these sugars, but without production of gas. On account of the quantity of acid produced, the two organisms were held to belong to the coli group. Only B. coli anaerogenes was pathogenic to mice, guinea-pigs, and rabbits. Trichorrhexis nodosa.* — Dr. St. Markusfeld finds that the disease- of the hair known as Trichorrhexis nodosa is produced by a bacillus which cau be demonstrated in all cases by staining and cultivation, and which will infect healthy hairs. The bacillus is endosporous, about 2 p, long and 0*5 p broad, and has rounded ends. It often forms filaments,, and is a facultative anaerobe. It is cultivable on bouillon, agar, and gelatin, the latter being liquefied. It coagulates milk. Pure agar cul- tures suspended in bouillon and inoculated on healthy hairs reproduced the disease. * Contralbl. Bakt. u. Par., lte Abt., sxi. (1897) pp. 230-4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 245 MICROSCOPY. A. Instruments, Accessories, &c.* (1) Stands. Stands and Optical Equipments.! — In an editorial article figures of two stands are reproduced from the latest catalogue (No. 20) of Reichert of Vienna. General remarks are made concerning oculars, and a list is given of the numbers, focal lengths, amplifications, and prices of the oculars of various firms. The apertures, 16 focal lengths, and prices of achromatic, apochromatic, and semiapochromatic objectives, both dry and immersion, are quoted from catalogues and compared. C3) Illuminating: and other Apparatus. Ocular-Dichroiscope.J — Herr C. Leiss figures a com- bined eye-piece and dichroiscope (fig. 16), with the aid of which the two colours shown by crystals of microscopic dimensions may be seen side by side, and so directly com- pared. This is an improvement on the usual method of rotating the polariser or the crystal. A rectangular dia- phragm is placed behind the calcite prism I\, as in the ordinary dichroiscope. (4) Photomicrography. Method of Projecting a Micrometric Scale upon a Microscopic Specimen. — The accompanying figure (fig. 17) illustrates the apparatus ■contrived by Prof. A. E. Wright for measuring and counting microscopic objects, described on p. 182, and exhibited at the March meeting of the Society. The window-pane and the projection-scale (which is etched upon a piece of plate glass) are shown in optical section at A and B respectively. The method of suspending the scale, so that it may be at right angles to the beam of light which is thrown upon the microscopic mirror, is shown at C. The scale is allowed to tilt forward until, as in medallions A and B, an equal number of vertical and horizontal divisions appear within 'the microscopic field. The minified image of the projection-scale, which is superposed upon the microscopic object, is shown in optical section at G. The adjustment of the condenser, which is essential to the super- position of the minified image upon the microscopic specimen, is most easily achieved by first focusing the microscopic objective upon the microscopic specimen, and then, while keeping this plane under observa- ^ * Tliis subdivision contains (1) Stands ; (2) Eye-pieces and Objectives ; (3) Illu- minating and other Apparatus; (4) Photomicrography; (5) Microscopical Optics .and Manipulation ; (6) Miscellaneous. t Zeitschr. f. angew. Mikr., ii. (1897) pp. 351-60 (2 fig?.). X Op. cit., iii. (1897) pp. 5-6 (1 fig.). 246 SUMMARY OF CURRENT RESEARCHES RELATING TO tion, making the necessary adjustment in the vertical height of the condenser. Medallion A (fig. 18) shows the figure of squares superposed upon the micrometric ruling of an ordinary stage micrometer, which is ruled in tenths of millimetres. Any line in the projection-scale can be super- posed upon any line of the stage micrometer by a mere movement of the mirror round its vertical or horizontal axis. When any one line of the projection-scale has been superposed upon any line of the stage micro- meter, all the other lines can be made to correspond by adjusting the distance between the projection-scale and the Microscope. Medallion B (fig. 19) shows the application of the projection-scale * to the enumeration of red and white blood-corpuscles. The appearances shown in the medallion are obtained by substituting for the stage micro- meter, shown in medallion A, a specimen of 200-fold diluted blood, which has then been filled into an unruled hasmc-cytometer-cell of a depth of 0*2 mm. The white bl col -orpuscles are most conveniently enumerated by * Projection-scales of this pattern maybe obtained from Mr. A. E. Dean, jun.^ 73 Hatton Garden, E.C. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 247 counting the number that fall within the area of the block of 25 squares. The red blood-corpuscles are most conveniently enumerated by counting the number which fall within the central square, which, to facilitate enumeration, is here divided into four smaller squares. The number of red and white blood-corpuscles in one cubic millimetre of blood can be conveniently arrived at by superposing the scale in turn Fig. 18. Fro. 19. upon ten different portions of the microscopic specimen, and by then multiplying the total red and white blood-corpuscles which were found in the areas which have just been specified by 10,000 and 400 respec- tively. In fig. 17, D represents the substage condenser, E the slide or haemo- cytometer-cell, and F the cover-glass. (5) Microscopical Optics and Manipulation. Knife and Strop for Microtomes.* — Herr G. Marpmann mentions the advances made in section-cutting since the introduction of the micro- tome ; he figures a knife made during the last 17-18 years by W. Walb of Heidelberg, and mentions a sharpening strop with rounded surface, also made by W. Walb. B. Technique.! (1) Collecting- Objects, including- Culture Processes. Nutritive Medium for Algae. — In his important work on Repro- duction in Algae and Fungi, J Dr. Klebs recommends, for the culture of Algae, the employment of both fluid and solid media. As a fluid medium he finds Knop’s the best, viz.: — 4 parts calcium nitrate, 1 part magne- sium sulphate, 1 part potassium nitrate, 1 part potassium phosphate. * Zeitschr. f. angew. Mikr., iii. (1897) p. 6 (1 fig.). ''***''' f This subdivision contains (1) Collecting Objects, including Culture Pro- cesses; (2) Preparing Objects; (3) Cutting, including Imbedding and Microtomes; (4) Staining and Injecting; (5) Mounting, including slides, preservative fluids, &c. ; (6) Miscellaneous. % Vide ante , p. 147. 248 SUMMARY OF CURRENT RESEARCHES RELATING TO In preparing it, a concentrated solution (B) may be made of the last three salts, and another (A) of the first. A proper amount of A is to be added to B after dilution to the desired percentage. By this method only a small part of the insoluble calcium phosphate will be precipitated. Solutions containing 0*2 to 0*5 per cent, of salts were found most useful. Cultivating the Bacillus of Seborrhcea.* — M. Sabouraud has over- come the difficulty of isolating the bacillus of seborrhoea and of alopecia areata by cultivating in a very acid medium, the ingredients of which are as follows : — Pepton, 20 grm. ; glycerin, 20 grm. ; acetic acid, 5 drops ; water, 1000 grm. ; gelose, 13 grm. The temperature used was 35° C. A white coccus was disposed of by using immunised gelose ; i.e. by preparing the gelose with fluid in which the coccus had been cultivated. The same result was obtained by heating the cultures to 65° C. for 10 minutes. Preparing Plague-Serum.f — Prof. A. Lustig and Dr. G. Galeotti prepare a vaccine from the plague bacillus which has the chemical characters of a nucleo-proteid. The bacillus, the virulence of which has been ascertained, is cultivated on large agar plates for three days at 37°. The surface is then scraped, and dissolved in 1 per cent. KHO. After filtration through paper, the vaccine is obtained by precipitation with acetic or hydrochloric acid, or by saturation with sulphate of am- monium after neutralisation. The precipitate, having been repeatedly washed, and dissolved in a very weak solution of sodium carbonate, is ready for use. Transit through the Chamberland filter deprives the vaccine of much of its activity. The minimum lethal dose of the acid precipitate is 5*28 mgrm. per 100 grm. weight of animal. Animals vaccinated with very small, or with one-half or one-third of the smallest fatal dose, injected subcutaneously at intervals of two days, are rendered quite indifferent to large injections of virulent cultures. The immunity lasts about five weeks. From animals thus rendered immune, is obtained, after 14 days, a preventive and curative serum, of which 1 ccm. suffices to prevent peritoneal infection and to cure a rat weighing 180-200 grm., which had been peritoneally injected with four to five loopfuls of virulent culture. The authors are endeavouring to obtain a prophylactic and antidotal serum from the horse. New Method of obtaining Diphtheria Antitoxin.^ — Dr. Smirnow, of St. Petersburg, has succeeded in obtaining a diphtheria antitoxin, which is stated to be of considerable effective value, by electrolysing virulent diphtheria broth cultures. In itself the antitoxin appears to be quite harmless, and its preparation simple and rapid. Technique of Serum Diagnosis.? — Dr. A. S. Delepine, after alludiug to the methods used since the beginning of 1896 for demonstrating the action of blood or blood-serum on the corresponding microbes, states that he has finally adopted the following simple but effective procedure, for * Brit. Med. Journ., 1897, i. p. 1029. f Tom. cit., pp. 1027-8. X Arch. Sci. Biol. Petersburg, iv. (1S96) No. 5. See Nature, April 22, 1897, pp. 597-8. § Brit. Med. Journ., 1897, i. pp. 967-70. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 249 which all the apparatus required consists of (a) a sterilised lancet-shaped needle ; (b) the small pipette in which the blood has been collected, and of such diameter that after it has been broken across (the platinum loop, which is used for measuring the serum, can easily be introduced into it if necessary) ; (c) a platinum loop, measuring about 1 mm. in diameter, and holding about 1 mgrm. of fluid ; (d) slide and cover-glass ; (e) a tube- culture of the typhoid bacillus in neutral bouillon. The culture should not be more than 24 hours old, should be free from clumps, and the bacillus actively motile. The procedure is as follows : — With the sterilised loop nine drops of the culture are deposited separately on slide or cover-glass. One drop of blood is then added, and the 10 drops thoroughly mixed together. The phenomena observed differ according to whether the serum is potent or not. If the serum be potent, all the bacilli will be agglomerated in from five to thirty minutes ; if feeble, the clumps form gradually, but positive diagnosis can be made in from about a half to two hours. For further information and details the original should be consulted. (2) Preparing- Objects. Preparing and Staining Celery for Demonstrating Bacteria.* — Dr. TJ. Brizi hardened the diseased parts for 48 hours in a liquid composed of 100 parts of water, to which were added 1 part of glacial acetic acid and 1 part of chromic acid. The pieces were further hardened in 75 per cent., and then in absolute alcohol. The sections were cut by the par- affin method, and after the paraffin had been removed by means of chloro- form, were washed in warm water and then immersed in an aqueous 1 per cent, solution of methyl-green for three or four hours, after which they were treated with water acidulated with hydrochloric acid. In this way -everything but the bacteria was decolorised, and then the sections were contrast-stained in an aqueous solution of picrocarmin, in which they were allowed to remain for about an hour. The sections, having been washed and dehydrated, were mounted in balsam. Another good stain was gentian-violet and acetic acid (water 100, acetic acid 10, saturated alcoholic solution of gentian-violet 20). The sections were treated with this solution for about an hour, and then placed in strong spirit to which a few drops of hypochlorite of soda were added. By this procedure the tissue was quite decolorised, the bacteria being stained violet. Microchemical Methods for Examining Cells.j — According to Prof. .E. Zacharias, a mixture of methylen-blue and fuchsin S maybe used with great advantage to study the distribution of nuclein in the cell. If tissues of different origin are treated with dilute hydrochloric acid, and this mixture afterwards added, the constituents of the cell which contain nuclein are stained a deep blue, the parts without that substance being red. Sperm-cells of the Rhine-salmon were treated with dilute hydro- chloric acid to remove protannin, and then stained with the above mixture. Instantly the envelopes of the heads which contain the nucleic acid were beautifully stained bright blue ; the inner part of the heads seemed to be colourless ; the tails were stained red. Similarly treated, 1897 * Atti R. Accad. Lincei, vi. (1897) pp. 229-34. t Rep. 66th Meeting Brit. Ass., 1896, p. 1022. S 250 SUMMARY OF CURRENT RESEARCHES RELATING TO the chromatin bodies of all the nuclei which have as yet been examined were stained blue, the rest of the nuclei and the cell-protoplasm red. Employment of Dead Bacteria in the Serum Diagnosis of Typhoid and Malta Fever.* — Prof. A. E. Wright and Surgeon-Major D. Semple confirm Widal’s observation that the agglomeration phenomenon is equally characteristic with dead bacteria, and they further find that it also holds good for Micrococcus melitensis. Emulsions of fresh agar cultures were drawn up into small glass capsules, and these exposed to a tempera- ture of 60° C. for five to ten minutes. The dead bacteria capsules were laid aside for three to nine weeks, and then, having been well shaken up, were used for serum diagnosis. Microscopical observation did not reveal any differences in the method in which agglomeration occurred in the living and dead cultures after addition of dilute serums ; and the experi- ments with capillary sero-sedimentation tubes gave even more interesting results. (3) Cutting-, including1 Imbedding and Microtomes. Cutting and Mounting of Sections of Cereal Grains.f — Mr. J. D. Hyatt says that, for making satisfactory sections of grains, the main precaution consists'in slightly moistening the kernels. Indian corn may be kept moist for 24 hours, wheat four or five hours, rye five or six, barley ten or twelve, and oats not more than one or two hours. For imbedding, paraffin is the best material, as it holds the grain so firmly that it may be cut in any direction. Any section-cutting contrivance will serve, provided the knife be sharp. If the sections be too thin the starch-grains will fall out, and if too thick the gluten cells will be disagreeably opaque. Glycerin-jelly is the best medium for mounting. The sections are best removed from the knife by a camel’s hair brush, and are then deposited in water, from which they are transferred to the centre of a horizon- tally placed slide. Warm glycerin-jelly is then put on, after which a cover-glass, slightly heated over a spirit-lamp, is carefully deposited on the gelatin. The cover-glass must be allowed to settle gradually and by its own weight, no pressure being applied. If the gelatin have become too hard to allow the cover to settle, the cover may be pressed, and then heat applied to the under-surface of the slide. (4) Staining and Injecting. Effect of certain Chemical and Physical Agents on the Staining of Sporous and Asporous Bacteria.f — M. C. X. Hierocles exposed the following bacteria, B. mycoides , B. subtilis} drumstick bacillus, a thermo- philous species cultivated at 56° C., typhoid and diphtheria bacilli, to the influence of certain agents, to ascertain whether the action of the latter improved or deteriorated the absorption of pigments in solution. Aqueous and anilin-water fuchsin solutions were used. Dry and moist heat increased the stainability of sporogenous bacteria and their rest- ing forms for anilin-water fuchsin. B. subtilis and B. mycoides stained * Brit. Med. Journ., 1897, i. pp. 1214-5. f Journ. New York Micr. Soc., xiii. (1897) pp. 19-24 (1 pi.). $ Arch. f. Hygiene, xxviii. p. 163. See Centralbl. Bakt. u. Par., lte Alt., xxi, (1897) pp. 416-7. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 251 better with aqueous solutions. Chlorine and bromine water increased the power of anilin-water fuchsin, and somewhat decreased that of aqueous fuchsin. Bromine vapour was detrimental to spores and bacilli; while chlorine gas seemed to make the spores and bacilli of B. subtilis and the drumstick bacillus stain more easily. Formalin and iodopotassic iodide solution had no effect ; and sunlight diminished the stainability of subtilis bacilli and spores. Chlorine gas was detri- mental to typhoid bacilli for aqueous fuchsin solution, and bromine vapour destroyed the cell-plasma. The effect of the agents used was to make diphtheria bacilli swell up, and their staining paler. = New Haematoxylin-Stain.* — The following process is recommended by Herr M. Baciborski. Leave the preparation for from 2-20 minutes in Delafield’s haematoxylin ; then wash with water, and for 2-5 minutes with iron-alum, then again with water, alcohol, and toluol, and imbed in canada-balsam. This process affords very good results for botanical purposes, and has the advantage of a great saving of time. Secondary staining with saffranin (in anilin water), and washing in 1 per cent, alcoholic acetic acid, affords a good double-stain. Flagella Staining.! — Mr. D. McCrorie stains flagella with “ night- blue,” an anilin pigment which shows as well in artificial as in sun- light. The formula used is, 10 ccm. of a concentrated solution of night-blue, 10 ccm. of a 10 per cent, solution of alum, and 10 ccm. of a 10 per cent, solution of tannic acid. The addition of 0-1-0 *2 grm. of gallic acid seems to impart additional value, but excellent results are obtainable without it. The method adopted is to dry the film in an incubator for two minutes ; then pour on the stain and incubate again for two minutes, or hold the cover for the same time about two feet above a Bunsen burner ; wash off the excess of stain, and, after drying- in an incubator, mount in balsam. (6) Miscellaneous. Method of extemporising a Blowpipe for making Sedimentation Tubes.! — Prof. A. E. Wright and Surgeon-Major D. Semple use an ordi- nary spray producer, such for instance as an ether freezing apparatus ; the reservoir is filled with methylated spirit. The flame produced in this way is quite hot enough for any ordinary glass-working apparatus. It is quite hot enough to draw out glass tubing into capillary sero-sedi- mentation tubes. Only two points in connection with the working of the flame required to be attended to, viz. (1) the spirit must be finely divided, i.e. the spray must not be too coarse, otherwise the flame will not be sufficiently hot ; (2) the spirit must be fed into the spray tube in sufficient quantity and in a regular manner. Botanical Application of the Rontgen Rays.§ — Herr J. Istvanffy has experimented on the effect of the light of Crookes’s vacuum-tubes on plants. He finds that the rays penetrate only the woody tissue, as can be made manifest in a leaf of Camellia , the veins of which appear white * Flora, lxxxiii. (1897) p. 75. t Brit. Med. Journ., 1897, i. p. 974. % Tom. cit., p. 1215. § SB. K. Ungar. Naturw. Gesell. Buda-Pest, Feb. 12, 1897. See Bot. Centralbl., xlix. (1897) p. 267. 252 SUMMARY OF CURRENT RESEARCHES RELATING TO in the image. All other tissues, whether containing chlorophyll or not, are impermeable to these rays. Demonstration of the Evolution of Oxygen by Diatoms.* — Mr. T. 0. Palmer has succeeded in demonstrating the absorption of carbon dioxide and the elimination of oxygen by diatoms experimentally by the following process, dependent on the property of hematoxylin of assuming a yellow colour with a tinge of brown when absorbing C02, while, in the presence of nascent oxygen, the red hue gradually deepens, finally becoming a deep blood-red. In the apparatus here figured (fig. 20), the dish is filled up to the line D E with water tinted with a freshly made solution of luematoxylin, sufficient to stain it a pale red. The tube A is then filled with the same solution, stopped with rubber, through which is passed a quill tube, and the tube suspended, the very fine end of the quill dipping into the water. Another portion of the hematoxylin Fig. 20. solution is acidified by C02 from the lungs, blown into it through a glass tube, till it assumes a brownish-yellow tint, and the tubes B, C, prepared in the same way, are filled with this solution ; living diatoms {Eunotia major ) having been placed in tube C. The apparatus is now exposed to bright light, preferably to direct sunlight. Gas arises from the diatoms in tube C, and simultaneously the colour of the liquid, which is at first like that in B, begins to change. Within 15 minutes the colour has again become almost or quite as red as that in tube A. The C02 has now, in large measure, disappeared from the solution. The action continues, and the colour in tube C deepens rapidly, showing oxi- dation, and this action continues until the colour is blood-red. Still more striking results are obtained as follows : — In tube A is placed a living snail ; in B live diatoms ; C being left for comparison. Under the influence of sunlight, in the course of a few minutes, A pales * Proc. Acad. Nat. Sci. Philadelphia, 1897 pp. 142-4 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 253 rapidly from the C02 given out by the snail ; B as rapidly darkens and reddens ; while C remains unchanged. Microchemical Reaction for Nitric Acid.* — Mr. J. L. C. Schroeder van der Kolk has for several years used the following test, which is somewhat similar to that recently proposed by R. Brauns, j The sub- stance to be tested is placed with a drop of sulphuric acid in the hollow of a glass slide, and from the cover-glass hangs a drop of barium hy- droxide solution ; when nitric acid is driven off, typical crystals of barium nitrate appear in the drop on the cover-glass. As the substance tested does not come into contact with the barium solution, the presence of sulphates, phosphates, &c., does not affect the result. Dead-Black Surface oil Brass. J — To 2 grains of lamp-black in a saucer add, says Mr. L. A. Wilson, just enough gold-size as will hold the lamp-black together, and mix thoroughly. Dip a lead pencil into the gold-size, and the right quantity will be obtained; add drop by drop. After the lamp-black and size are thoroughly mixed and worked up, add 24 drops of turpentine, and work up again. Apply the mixture with a camel’s hair brush. When thoroughly dry, the brass will look as if it had just come from the optician’s hands. Laboratory Notes. — Prof. K. Goebel § recommends the follow- ing objects for the purposes specified : — The leaves of Elatostemma sessile for the exudation of drops of water. Klugia notoniana for the forma- tion of the embryo within the ovule. The protoneme of Mosses for the formation of starch out of sugar. The germination of the protoneme from the spore can be well followed out in Fanaria Jiygrometrica. Herr M. Baciborski || finds the epidermal cells of the perianth- leaves of cultivated species of Albuca favourable objects for observing the formation of crystalloids in the vacuoles within the endosperm. No fixing or staining of the object is necessary. The elaioplasts can also be demonstrated in the same cells. Reversible Mailing Cases.lf — Messrs. Bausch and Lomb have brought out new mailing cases for microscopical slides. All the pieces are similar and interchangeable, thus avoiding the use of “ tops ” and “ bottoms.” An ample depression in the face of each piece allows the stowing of a slide with a large cover. Any number of slides and cases may be adjusted and piled one above the other, or one slide may be held securely by simply reversing one piece of wood. * Neues Jakrb. Mineral., i. (1897) p. 219. t Cf. this Journal, 1896, p. 687. X The Microscope, v. (1897) pp. 43-4. § Flora, lxxxiii. (1897) pp. 74-5. || Tom. cit., p. 75. Journ. New York Micr. Soc., xiii. (1897) pp. 41-2 (2 figs.). 254 PROCEEDINGS OF THE SOCIETY. MEETING Held on the 21st of April, 1897, at 20 Hanover Square, W., The President (E. M. Nelson, Esq.) in the Chair. The President having, in ' pursuance of notice given at the last meeting of the Society, declared the present meeting to be special for the purpose of making alterations in two of the Society’s rules, called upon Mr. J. J. Yezey — in the absence of Prof. Bell — to read the notice and the proposed alterations. Mr. Yezey then read the notice by virtue of which the special meet- ing was constituted, and also read Buies 10 and 20 in their altered form as follows : — “ Buie 10. Every person elected an Ordinary Fellow shall sign the following form of declaration, and shall pay the admission fee, or the first instalment thereof, as provided by Rule 20, and first annual sub- scription or composition, within two months from the date of election, or within such further time as the Council may allow. In default of such signature and payment the election of such Fellow shall be void. I, the undersigned , having been elected a Fellow of the Royal Micro- scopical Society, hereby agree that I ivill be governed by the Charter and Bye-laws of the Society for the time being ; and that I will advance the objects of the Society as far as shall be in my power. Provided that when I shall signify in writing to one of the Secretaries that I am desirous Donax trunculus j Capsa | Donax politus Psammobia Asaphis — Donax serra Petricola ] Venus — —Tapes \ Yeneridae Cytherea ' Cardita 1 Dreissensia 1 Cyprina 1 Astarte Mytilus OstreidsB Limidae I Anomiidae — j Primitive Astartidae ? Odontopsis Modiola — Arcidae Aviculidae Pectinidae | Rkombopteria -Nueulidae Nuculoid Stammform ? Nuculites and Praearca * Comptes Rendus, cxxiv. (1897) pp. 693-5. f Jen. Zeitschr. f. Naturwiss., xxxi. (1897) pp. 29-89 (2 pis.). 200L0QY AND BOTANY. MICROSCOPY, ETC. 279 Embryonic Shell of Bivalves.* * * § — M. Felix Bernard describes the em- bryonic shell or “ prodissoconque ” in a number of Lamellibranch types. The stage which shows it is well marked, it is a period of rapid embryonic growth and differentiation, it is terminated by a short period of arrest. He argues that the larva with the prodissoconque represents an ancestral type — with its two adductors, its pedal muscles, its three pairs of ganglia, its creeping foot, its mantle with free lobes and no siphon, its gills situated far back, its velum, and so on. Antecedent to the prodissoconch is the protostracum without cardinal differentiation, as seen in the Glochidium larva ; this earliest stage he has succeeded in demonstrating at the apex of all the prodissoconques studied. Arthropoda. Appendages of Arthropods.f — Herr A. Jaworowski returns to his theory that Arthropod appendages [and gills in Crustacea] are refer- able phylogenetically to respiratory insinkings of the skin. Anatomical, developmental, and pathological facts all seem to him to point to the conclusion that mouth-parts, limbs, wings of insects, eye-stalks of Crus- tacea, &c., are referable to primitive folded lung-like insinkings of the skin. His arguments do not appear to us in any way conclusive, but they are of the sort often used in speculative phylogenetic studies, and are nothing if not ingenious. They lead him to renewed confidence in the unity of the Arthropod Ur stamm. a. Insecta. Aquatic Insects of the Illinois River .J — Mr. C. A. Hart publishes the first paper of a memoir on the insect fauna of the Illinois River and adjacent waters. It is designed partly as a basis for further work, and partly for the use of Illinois students. It is admirably conceived as a faunistic guide, giving prominence to the nutritive and other bionomical relations of the forms described, and to their life throughout the year. Myasis of Alimentary Canal in Man.§ — Dr. P. Lallier has pub- lished his thesis on this subject. He has compiled a very complete record on the subject, and furnishes a useful bibliography. There is no doubt that larvae of Antliomyia, Sarcophaga, Musca, Calliphora, Teichomyza, &c,, may live for some time in the food-canal of man. The author discusses their introduction, effects, and distribution, and the medicinal treatment of cases. Viviparity in Ephemerids.|| — Dr. R. Heymons directs attention to M. Causard’s IT observation of viviparity in Cloeopsis diptera Latr., and points out that von Siebold noted the viviparous birth of an Ephemerid in 1837, and Calori (in Cloeon dipterurn) in 1841. Causard’s observation is very welcome, but not altogether novel. Heymons notes further that viviparity may be more frequent in southern regions, for Cloeon dipterurn is demonstrably oviparous in Berlin. * Comptes Rendus, exxiv. (1897) pp. 1165-8. f Zool. Anzeig., xx. (1897) pp. 177-84 (3 figs.). X Bull. Illinois Lab. Nat. Hist., iv. (1897) pp. 149-284 (15 pis.). § ‘Etude sur la My asedu tube digestif cliez rhomme.’ These. 8vo, Paris, 1897, 120 pp., 1 pi. || Zool. Anzeig., xx. (1897) pp. 205-6. t Comptes Rendus, cxxiii. (1896) p. 705. U 2 280 SUMMARY OF CURRENT RESEARCHES RELATING TO Luminosity of Glowworms.* — Dr. H. Muraoka lias studied tlie phy- sical character of this light. In its natural state it behaves like ordinary light. The filtered rays, like Becquerel’s fluorescence rays, seem to have characters midway between ultra-violet rays and Rontgen rays. Seasonal Dimorphism in African Butterflies.! — Mr. A. G. Butler re- turns to his thesis, in answer to some criticisms by Mr. G. A. K. Marshall.^ His point is this : — “ In a country which is hot and dry throughout the year, wet-season forms will be naturally extremely rare (if present at all), whereas the reverse will be the case in a uniformly moist climate. Now, where a species ranges throughout Africa to Arabia, it exhibits in one locality a single type (say dry-season), and perhaps in abnormal seasons, when light showers fall, a second type (intermediate between dry and wet) ; or, if the country be moist, a wet-season and an inter- mediate-season form occur, but no dry-season form.” Zeuzera iEscu!i.§ — M. Laboulbene describes the caterpillar of this butterfly. It is a borer and wood-eater, and has been doing much damage to trees in Morocco. Optic Lobes of Bee’s Brain. || — Mr. F. C. Kenyon gives an account of the minute structure of these bodies. It is too complex to be profit- ably summarised without a diagram ; but the following sentence may be cited : — •“ It appears that, setting aside the outer or retinal elements, there are concerned in the transmission of visual stimuli to the central portion of the brain some six or seven neural elements, and that such stimuli may reach (1) the optic body, (2) the mushroom bodies, and (3) the hinder lower portion of the brain, and that they may pass over one or other of the optic commissures — provided the upper one is a real commissure — to the inner fibrillar body of the opposite lobe, and thus indirectly reach the mushroom bodies, the optic bodies, and the posterior region of the brain on the opposite side.” Danish Galls.1T — Sofie Rostrup gives a list of the Danish gall-forming animals and of the plants infested. The list includes, besides insects {Coleoptera, Hymenoptera, Lepidoptera, Diptera, and Phytophthires), a number of Acarina and Nematoda. Odonate Nymph from a Hot Spring.** — Mr. D. S. Kellicott notes the occurrence of dragon-fly nymphs in a hot spring. The exact tem- perature at the time and place of capture was not ascertained, but the water in the pool (45 ft. long) was near the boiling point at one end, as low as blood-heat at the other. Some of the nymphs were taken at the hottest part of the pool. As the larvae are carnivorous, other animals must be present. Mouth-Parts of Insects.f f — Dr. J. B. Smith has studied the develop- ment of the mouth-parts in a large number of insects. As to the labial structures, he concludes that mentum and submentum may unite and * Journ. Coll. Sci. Imp. Univ. Japan, ix. (1897) pp. 129-39. t Trans. Entom. Soc. London, 1897, pp. 105-11. f Op. cit., 1896, p. 551. § Bull. Soc. Nat. d’Agriculture de France, Ivi. (1896) pp. 646-52. H Amer. Nat., xxxi. (1897) pp. 369-76 (1 pl.). ^1 Yidensk. Med. Kjobenhavu, 1896, pp. 1-64. ** Journ. Cincinnati Soc. Nat. Hist., xix. (1897) pp. 63-5 (2 figs.), ft Trans. Amer. Philos. Soc., ix. (1897) pp. 175-98 (3 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 281 tend to become internal head-structures. The ligula is rarely paired, may be rigid or flexible, and has closely associated with it the hypo- pharynx. The paraglossre are never jointed, and tend to become obso- lete. The labial palps are essentially tactile. From the most generalised type, found in the Blattidae, the modification is first from a divided to a single ligula ; next to a disappearance or obsolescence of the paraglossse ; later the labial palps also disappear, and finally the hypopharynx is dis- pensed with. As to the maxillte, the sclerites form three series, each of which has its own possibilities of development. The lacinia never develop except as chewing or piercing organs, the galea varies in the direction of form- ing an enveloping organ for all the other mouth-parts, and the subgalea eventually unites along one margin for that purpose. There is a ten- dency to develop a ridged membrane on the inner surface of the galear joints, which culminates in the pseudotrachea of the muscid labella. The palpifer has a small range of development, from an unjointed flexible tactile organ to a rigid piercing structure, and, as this becomes useless, to a process for the attachment of muscles used to flex the proboscis. Classification of Orthoptera.* * * § — M. L. Bordas divides Orthoptera into — (I.) Acolotasia, ivithout diverticula at the anterior end of the mid- gut (Phasmidee and Forficulidae), and (II.) Colotasia, with intestinal diverticula, more or less numerous (Blattidae, Mantidae, Acrididae,. Locustidae, and Gryllidae). The classification, primarily based on the absence or presence of caeca, is elaborated in reference to the number and arrangement of the Malpighian tubules, the structure of the giz- zard, &c. Development of Apterygota.f — Dr. B. Heymons has studied the development of Lepisma saccharina L. The segmentation is peripheral, not total, and an amnion and serosa are developed. Thus the Inseeta apterygota are not exclusively anamnia, as is usually said. At the same time, it must be noted that in Lejpisma the amnion-cavity is a large space between the blastoderm and the surface of the egg, and that there is no complete separation of amnion and serosa, an amnion pore being left. The antithesis between the Pterygota and the Apterygota is thus lessened by Lepisma and its relatives. Check-List of Coccidae.f — Mr. T. D. A. Cockerell points out that, there is at present, as the ‘ Zoological Record ’ shows, unusual activity among coccidologists. A check-list, complete to date, has been a deside- ratum, and this he has now supplied. In his list he ignores all £; nomina nuda ” (names without description), and separates off the “ nomina serni- nuda” (with inadequate description) from the “ nomina valida,” of which 773 are recorded. Mosquito-Bite. § — Mr. E. S. Morse has an interesting letter in Nature on acquired immunity from mosquito-bite and insect stings. Mr. G. Macloskie, in the same number, describes the mosquito’s three pairs * Comptes Kendus, cxxiv. (1897) pp. 821-3. t SB. Akad. Wiss. Berlin, 1896, pp. 1385-9. X Bull. Illinois Lab. Nat. Hist., iv. (1896) pp. 318-39. § Nature, lv. (1897) pp. 533-4. 282 SUMMAIlY OF CURRENT RESEARCHES RELATING TO of salivary glands, and the union of their six ductules into a common duct which leads into the hypopharynx. This injects the toxin into the wound. Natural Bepellent Effect of “Warning Colours.”* * * § — Dr. A. Alcock describes the behaviour of a very docile young Himalayan bear, which showed a marked appetite for grasshoppers. It crunched with every sign of relish the common bright-green and dull-brown grasshoppers found in Calcutta. On the other hand, it strongly objected to the glaring- coloured and evil-smelling Autarches miliaris L., which has an abdomen with alternate stripes of black and scarlet, and black fore- wings with canary-yellow spots. This insect secretes a most peculiarly pungent-smelling frothy fluid ; but after the bear had once smelt it, the mere sight of it seemed to be enough for him. Dr. Alcock does not, however, say at what distance the bear could smell the grasshopper. So far as the observation goes, it seems to him to support the belief £t that when an insect has been found by experience to be unpleasant to (taste and) smell, it has only to be seen to be avoided ; and that any conspi- cuous markings that lead to the immediate recognition of such an insect by eyesight and at a distance are likely to be of such benefit to the insect as to be acted on by Natural Selection.” Ejection of Offensive Liquids by Insects. f — Sig. Y. Izquierdo has observed various cases of the defensive ejection of irritant fluids by insects. Colours of Lepidoptera.J — Mr. A. G. Mayer has made some interest- ing investigations on the colours and colour-patterns of moths and butterflies. He has analysed the colours in many cases by means both of the spectroscope and of Maxwell’s discs, and finds that pure colours are very rare, a percentage of black being almost always present. He has further studied the development of colour in the wings of Callosamia yrometliea and Danais plexijpus Fab., and has confirmed the results of previous authors as to the order of development. A series of experiments with the wings of butterflies with and without the scales failed to show that the latter in any way affect the power of flight, and the author therefore concludes that the scales are only of importance in connection with colour-production. The second part of the paper contains a detailed account of colour-variation in the Heliconidac, the observations, in the author’s opinion, all tending to support the theory of mimicry. The paper includes a copious bibliography and numerous tables of variation. Notes on Termites.§ — Herr K. Czenvinski has found the larvae of the “ soldiers” and “nasuti” in a species of Eutermes from Brazil. He has also found the frontal gland in imago, nymph, and worker. It is multicellular, most complex in the “ nasuti,” and opens at a white spot or ££ fontanelle ” where the chitin is very thin. There is a paired and an unpaired system of sympathetic nerves, both arising as short strands * Journ. Asiatic Soc. Bengal, lxv. (1896) pp. 539-40. f Actes Soc. Scient. Chili, 5tli part of vol. v. (1895, published March 1897 !) pp. 257-G1 (1 fig.). J Bull. Mus. Comp. Zool. Harvard, xxx. (1897) pp. 169-256 (10 pis.). See also Proc. Boston Soc. Nat. Hist., xxvii. (1897) pp. 243-330 (10 pis.). § Zool. Anzeig., xx. (1897) pp. 199-202. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 283 from the brain. In front of the superior oesophageal ganglion lies the frontal ganglion, from which the oesophago-gastric nerve runs backwards beneath the brain close to the oesophagus. Behind the brain it becomes connected with the paired system. From the head it extends to the thorax, and forms a stomach ganglion. The paired system consists of two pairs of ganglia, close behind the brain, connected by commissures with one another and with the unpaired system. In short, the system is like that of Orthoptera. New Scale-Insects.'* * * §' — Mr. W. G. Johnson describes five new species of scale-insects : — Aspidiotus forbesi on cherry, apple, pear, plum, &c. ; A. comstocki on sugar maple ; A. sesculi on buckeye ; A. ulmi on white elm ; and Chionaspis americana on the same. 8. Arachnida. Oogenesis in Pholcus.f — Prof. Ch. Van Bambeke describes the changes in the ovarian ovum of Pholcus phalangioides Fuessl. during the period of growth. Four stages may be distinguished, especially as regards the formation of the nutritive vitellus. (1) First there is the appearance and development of a structure which probably represents the vitelline body of Balbiani. (2) Then follows the disintegration of this vitelline body. (3) The third stage is marked by the fact that the elements derived from the disintegration of the vitelline body are transformed into fatty drops and granules. (4) In the fourth stage the germinal vesicle loses its definite wall, and comes into more intimate relations with the cytoplasm. The latter, becoming more active, secretes or elaborates the materials which give rise to the vacuolisation of the vitellus. The adipose granules pro- bably furnish the material which renders the cytoplasm more capable of forming the vitelline spheres or true nutritive vitellus. Mites and Ants.J — Herr E. Wasmann discusses the myrmecophilous mites which infest ants. They occur in the Hypopus- form, and it seems difficult to refer them to their proper genus, Tyroglyphus or some other. A single ant may bear hundreds or even thousands of mites, all lying in the same way, with their head pointing to the apex of the part on which they are fixed. Wasmann also speaks of the “ syntrophy ” of Lselaps oophilus Moniez, which occurs freely on the surface of the eggs of ants ( Formica sanguinea and F. rufobarbis ), but without doing them any damage, apparently depending on the salivary secretion of the ants, which are always licking their eggs. e. Crustacea. .Pigments of Lobster. — Miss M. I. Newbigin § has investigated the pigments of Homarus , Nephrops, and Astacus. She succeeded in obtain- ing a blue pigment in solution from the exoskeleton of Homarus and Astacus , and believes that this pigment is of the nature of an unstable * Bull. Illinois Lab. Nat. Hist., iv. (1896) pp. 380-95 (6 pis.), t Bull. R. Acad. Belg., xxxiii. (1897) pp. 307-21, % Zool. Anzeig., xx. (1897) pp. 170-3. § Journ. Physiol., xxi. (1897) pp. 237-56. 284 SUMMARY OF CURRENT RESEARCHES RELATING TO combination between a red lipocbrome and an organic base, probably derived from tlie muscle. The red colour of the shell in Nephrojps is due to the same red lipochrome in combination with lime. The green colour of the eggs of the lobster the author finds to be due to the mingling of the blue pigment of the shell with a yellow pigment, which also occurs in the liver and shell, and which does not give the lipochrome reactions. There is some evidence to show that this yellow pigment is capable of being transformed into the red lipochrome. The author is of opinion that the yellow pigment of the liver (hepatochrome) is widely distributed among the Decapod Crustacea, that it may be modified into the red lipochrome which may directly colour the shell, or may become converted into the blue compound. The numerous colour variations of the group are thus in part accounted for. Photomechanical Changes in Retinal Pigment-Cells of Palsemc- netes.* — Dr. G. H. Parker gives the following general summary of his results. (1) The only parts of the retina in Palsemonetes that exhibit photomechanical changes are the three kinds of pigment-cells. (2) The proximal retinular cells contain black pigment-granules. In the light these are diffused with slight concentration at the distal end and around the rhabdome ; in the darlc the jugment is limited to the retinal nerve- fibres. (3) The change from the dark to the light condition takes 30-4.5 minutes ; the reverse change 45-60 minutes. (4) The changes are probably due to the internal protoplasmic movements. (5) The accessory pigment-cells have a yellowish-white pigment ; in the light this is massed partly at the base of the retina, partly near the distal surface of the first optic ganglion ; in the darlc it is almost wholly at the base of the retina. (6) The change from dark to light condition takes 45-60 minutes; the reverse change 105-120 minutes. (7) The changes are probably due to amoeboid movements of the cells. (8) The distal retinular cells contain black pigment granules. In the light they are contracted, and occupy a proximal position in the retina surrounding the axis of the ommatidium near the outer ends of the proximal retinular cells ; in the darlc they are expanded (flattened), and occupy a distal position in the retina, surrounding more or less completely the sides of the cone. (9) The change from dark to light condition takes 90-105 minutes ; the reverse change 105-120 minutes. (10) These changes are produced in part by an amoeboid movement of the cell, and probably in part by a muscle-like contraction of its axial portion. (11) Each set of photomechanical changes in the light is more rapid than the reverse set in the dark. (12) The conditions of the two eyes are quite independent. (13) The photomechanical action within the retina is localised, small groups of pigment-cells responding to local stimulation. (14) The changes may occur even if optic nerve is cut. (15) They may occur almost completely even on excised retinas, (16) Incompleteness in such cases is probably due to the death of the retinal tissue. (17) The three kinds of retinal pigment-cells probably respond to direct stimulation from without, and are not influenced by nervous impulses from within. There is no good evidence in favour of normal double conduction of nervous impulses. * Bull. Mus. Harvard, xxx. (1897) pp. 275-300 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. •285 Trapeziidse.* * * § — Dr. A. E. Ortinann furnishes a systematic revision of this family of Decapods — a revision which seems to be much needed. He brings structural characters (of shape) into the foreground, and corrects the undue emphasis which has been laid upon colour. Three genera are recognised, — Trapezia , Tetralia, and Quadrella. The Tra- pezikke live among living corals, excepting only Quadrella coronata from among pearl-mussels. They are strictly littoral animals of the low- tide mark zone, the deepest habitat recorded being 22 fathoms for Trap, cymodoce. They occur in the whole Indo-Pacific region where there are coral-reefs ; they are entirely absent, however, from the east side of America. The conclusions to be drawn from the distribution are discussed at some length. Hew Paguridse.'f — Prof. J. R. Henderson reports on fourteen species collected by the £ Investigator ’ in 1893-4 in the Indian Ocean. Of the fourteen, no less than seven are newr — Eupagurus pergranulatus, Pylo- pagurus magnimanus, Gdtapagurus muricatus , Paguristes pusillus, P.puni- ceus, Parapagurus andersoni , and P. minutus. The large proportion of new species is not remarkable when the deep-water habitat of the majority is taken into consideration. Freshwater Crustacea of South Africa.^ — Prof. M. Weber’s memoir on the freshwater fauna of South Africa includes an account of the Crustacea collected. In this he was helped by Dr. J. C. PI. de Meijere and Dr. J. G. De Man. The new forms are Sesarma eulimene De Man, and Leander capensis De Man. The whole collection included only twelve species, and of these only Telphisa is regarded as genuinely “ re- gional and local.” Other forms, such as species of Palsemon and Caridina , Sesarma eulimene , and Varuna litterata, are regarded as immigrants from the sea. Mysidse of the Caspian. § — Prof. G. 0. Sars describes a collection made by Dr. Grimm. The largest is a very magnificent form, Paramysis Eessleri, nearly 40 mm. in length. Between Paramysis and Mesomysis, a new genus Metamysis is established. The collection includes six new species. New Cave Isopod. j| — Dr. B. Nemec describes Trichoniscus stygius sp. n. from the Gabroviza grotto near Trieste. It certainly belongs to the genus Trichoniscus , but it is probably identical with Joseph’s Typhloniscus stygius. The author discusses in a very unprejudiced manner the possible origin of blind cave animals, like this Isopod, whether (1) from congeni- tally blind ancestors who found the caves safe and congenial, or (2) from ancestors whose eyes degenerated in darkness, either (a) by direct modification, or (b) indirectly, the absence of light determining the direc- tion of intra-selection and germinal selection. Amphipods of the Caspian.1T — Prof. G. 0. Sars describes 25 species of Amphipods from the Caspian, which raises the number of carefully * Zool. Jahrb. (Abth. Syst.), x. (1897) pp. 201-16. t Journ. Asiatic Soc. Bengal, lxv. (1896) pp. 516-36. t Zool. Jahrb. (Abth. Syst.), x. (1897) pp. 135-200 (1 pi.). § Bull. Acad. Imp. Sci. St. Pe'tersbourg, iii. (1895) pp. 433-58 (8 pis.). || Yerh. K. K. Zool. Bot. Gesellscli. Wien, xlvii. (1897) pp. 58-64 (1 pi.). 1 Bull. Acad. Imp. Sci. St. Petersbourg, iv. (1896) pp. 421-S7 (12 pis.). 286 SUMMARY OF CURRENT RESEARCHES RELATING TO examined forms to 53. They belong to four different families — Lysia- nassidae, Pontoporeiidse, Corophiidae, and Gammaridae, the last being most abundant. The collection described included 15 new species. New Species of Branchipus * * * § — Dr. A. Alcock describes and figures a large and beautiful form — Brancliijpus ( Streptocephalus ) hengalensis sp. n., — found in flooded rice-fields near Calcutta. It is most closely related to Br. rubricaudatus Klunzinger from Arabia, and, through the female, to Br. torvicornis Waga from Warsaw, The body is rather over an inch long. The antennae of the male are more than half as long as the body ; those of the female form a pair of short broad leaf-like lobes, bending, in repose, over the eyes, like curtains. North American Freshwater Ostracods.t — Mr. R. W. Sharpe gives an account of North American Cytheridae and Cyprididae, discussing 22 species. Fourteen of these are new to America, and about a dozen new to science. Two of these new forms belong to the genus Limnicythere , itself new to America. The systematic part of the paper is preceded by an interesting account of local and seasonal distribution prepared by Mr. C. A. Hart. Olfactory Setse of Cladocera.J — Mr. D. J. Scourfield gives a short account of the structure, number, and arrangement of the peculiar little setae on the first pair of antennae in the Cladocera, usually considered to be olfactory. It appears that in the females the number of such setae on each antennule is characteristic of families and groups of families. Thus the Polyphemidae have 5, the Holopedidae 6, and the remaining families, namely Sididae, Daphnidae, Bosminidae, Lyncodaphnidae, Lyn- ceidae, and Leptodoridae, 9 olfactory setae in each tuft. The number in the males is sometimes the same as in the females (Daphnidae), but often greater (Lynceidae). As regards the arrangement of the setae, cases are mentioned where it is possible to distinguish closely allied species simply by the relative lengths and positions of these minute structures. Some Manitoba Cladocera.§ — Mr. L. S. Ross has the honour of writing the first systematic paper on the Entomostraca of Manitoba, and it is on this account that we notice his contribution, which deals with 30 species, including Ceriodaphnia acanthinci , which is new. Pycnogonids.|| — M. E. Topsent reports on the Pycnogonids collected in 1894-6 in the North Atlantic by the Prince of Monaco. The collec- tion was very small, comprising only two species, Colossendeis gigas Hoek and C. leptorhynchus Hoek. The latter species was found by the * Challenger 5 only in the South Pacific and Indian Oceans. Annulata. Ovum Centrosome in Chsetopterus.f — Mr. A. D. Mead has convinced himself that the asters and centrosomes in the ovum of Chsetopterus pergamentaceus arise by a modification of the cytoplasmic reticulum. * Journ. Asiat. Soc. Bengal, lxv. (1896) pp. 538-9 (1 pi.), t Bull. Illinois Lab. Nat. Hist., iv. (1897) pp. 414-81 (10 pis.), j Journ. Quekett Micr. Club, vi. (1896) pp. 280-88 (1 pi.). § Amer. Nat., xxxi. (1897) pp. 293-303 (1 fig.). 11 Bull. Soc. Zool. France, xxii. (1897) pp. 106-7. 1 Journ. Morphol., xii. (1897) pp. 391-4 (3 fig3.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 287 The phenomena of their origin, and their relation to the secondary asters, are similar to those described by Reinke in the tissue-cells of the larval salamander. Regeneration and Autotomy in Earthworms.* * * § — Herr K. Hescheler made experiments in 1896 which showed that (in Lumbricus Herculeus , L. rubellus, Allolobophora foetida, All. caliginosa, All. terrestris) the rege- neration of a lost anterior end only occurred within narrow limits. When more than ten segments are lost, the regeneration decreases rapidly in completeness, and in most cases only four or five new seg- ments are formed. Morgan got similar results; but Joest and Korschelt reported extraordinary regenerative pow’er, far exceeding what Hescheler observed. As further experiments have confirmed Hescheler in his results, he suggests, in explanation of the discrepancy, that Joest and Korschelt must have worked with different species. Hescheler has also shown that autotomy ( Selbstamputation ) occurs in the posterior region of Lumbricus Herculeus , L. rubellus , Allolobophora foetida , All. clilorotica, All. caliginosa , All. terrestris , and All. cyanea . It is a general, habitual, and adaptive phenomenon, which may be in- duced by discomfort, by mechanical, chemical, and electrical stimuli, and in dying. The author compares what occurs in earthworms with obser- vations on Nephthys scolopendroides and Clisetopterus. What is limited in Lumbricus and Allolobophora is more pronounced in Allurus, and yet more so in Criodrilus , while Lumbriculus is reproduced by fission at certain seasons. New North American Oligochseta.f — Mr. Frank Smith describes from the Illinois river, at Havana, a new Naidomorph Pristina leidyi sp. n., closely allied to P. longiseta Ehrenb. ; also Mesoporodrilus asym - metricus g. et sp. n., in some important respects allied to Eclipidrilus frigidus Eisen. A Florida collection yielded Microscolex hempeli sp. n., which combines characters that seem to bring the genera Phododrilus and Leltania very near together, and to emphasise the necessity of com- bining them with Microscolex , as Beddard has done. In a previous paper J the author described Thinodrilus inconstans g. et sp. n., a new Lumbriculid. New 01igochgeta.§ — Dr. W. Michaelsen describes Prof. Kukenthal’s collection from Halmahera, Ternate, Borneo, &c. It includes among Oeoscolecidae Glypliidrilus KueJcenthali sp. n., and among Megascolecidae Pleionog aster ternatse sp. n. and seven new species of Perichseta. Among these there seems to be much variability ; thus no fewer than six sub- species of Perichseta halmaherse are distinguished. Heart-Body of Enchytrseidse.fl — Prof. J. Nusbaum and Herr Jan Rakowski have studied the structure of the dorsal vessel and the so-called Herzkorper in Fredericia and Mesenchytrseus, and conclude that the u heart-body ” is derivable from the blood-gland known in other Enchy- trmidse. The similarity of the histological characters and the similarity * Vierteljahrschr. Nat. Gesellsch. Zurich, xlii. (1897) pp. 51-61. f Bull. Illinois Lab. Nat. Hist., iv. Art. 11, pp. 396-113 (1 pis.). % Tom. cit., pp. 285-97. § Abli. Senckenberg. Gesellsch., xxiii. (1897) pp. 193-213 (1 pi., 1 fig.). {| Biol. Centralbl., xvii. (1897) pp. 260-6 (1 figs.). 288 SUMMARY OF CURRENT RESEARCHES RELATING TO of position — within the vessels, in association with the endothelium — point to the conclusion that all these structures in Enchytraeidse arc moiqohologically alike. What their functional import is remains obscure. Eyes of Hirudinea.* — Dr. R. Hesse describes the optic organs in about a dozen species of Hirudinea. He begins with the Gnatlio- bdellidae, where the eye-structure is simplest, and discusses Piscicola , Branchellion , Pontobdella , Clejpsine, &c. Among Ehynchobdellkke he describes Nephelis , Hirudo, &c. In many cases his descriptions are only supplementary to previous work by others. The optic cells form the structural basis ; they occur diffusely, or in stretches, or in close aggregates. They differ, of course, in detail, but they are all alike in being continued into a nerve-fibre, and in having vacuolar structures in their plasma. These vacuoles are the specific characteristics of# the optic cells, analogous to rods and cones. The pigment accumulations associated with tho optic cells are, as usual, “ Blendungsv or richt ungen .” In all Hirudinea, even in those without eyes, there are scattered optic cells ; in Clejpsine bioculata and Cl. sexoculata the number of free cells decreases as the eyes increase ; in Ichthyobdellidse only Piscicola has true eyes, in Pontobdella there are scattered optic cells, while Branchellion is between the two states. These and similar facts point to the conclusion that the eyes of Hirudinea have arisen by aggregation of optic cells, and by the closer association of these with pigment accu- mulations. Rotatoria. Some new Forms of American Rotifera.j — Dr. A. C. Stokes gives a description, with plate, of the following six “ presumably ” new species of Rotifers : — Proales hyalina , Notommata vorax, Biglena contorta, Mas - tigocerca sjpinifera , Cathy jpna scutaria , and Cathy pna glandulosa. The first-named, P. hyalina , is certainly Ehrenberg’s Notommata tuba , which Mr. C. Rousselet has recently described and renamed Cyrtonia tuba.% N. vorax seems to have considerable resemblance to Dujardin’s N. torulosa with its globular auricles, if it is not identical with it. Diglena contorta seems to have much in common with Ehrenberg’s N. forcipata , and, as it Das no eyes and possesses auricles, it is questionable if it be a Biglena. Dr. Stokes gives this form two dorsal antennm, which is a very unusual feature. Lacinularia elongata. a new Rotifer.§ — Mr. T. Shephard, in de- scribing this new Lacinularia , gives the following principal charac- ters : — Clusters fixed, with a dense matrix of adherent tubes of dirty brown colour ; body of individual narrow and much elongated ; corona only little wider than the body, slightly oval. A plate of five figures accom- panies the description. Brachionus bakeri and its Varieties.! — Mr. C. F. Rousselet’s object in figuring all the principal varieties of this Rotifer has evidently been * Zeitschr. f. wiss. Zool., lxii. (1897) pp. 671-707 (2 pis.). f Ann. and Mag. Nat. Hist , June 1897, pp. 628-33 (1 pi.). X Of. this Journal, 1895, p. 317. § Victorian Naturalist, May 1896 (1 pi.). II Journ. Quekett Micr. Club, vi. (1897) pp. 328-32 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 289 to check the growing practice of giving new names to every slight variety ; for this purpose, and also for reference, his plate of fourteen figures is very instructive and useful. Metopidia pterygoida, a new Rotifer.* * * § — Mr. M. F. Dunlop de- scribes and figures this pretty and peculiar new species with wing-like expansions of the lorica, but otherwise allied to Perty’s Notogonia ehrenbergi. N ematohelminthes. Classification of Nematoda.t — Dr. von Linstow criticises Schneider’s old classification into Polymyarii, Meromyarii, and Holomyarii, the de- fects of which have been previously indicated by Biitsckli and others. Yon Linstow distinguishes three families : — I. Secernentes. The lateral line bears a ridge or cushion with a narrow base, which expands internally and projects beyond the muscles. In both cushions or in one there is a longitudinal vessel opening ven- trally at the excretory pore. Examples : — Ascaris osculata, Oxyuris vermicularis, Ankylostomum duodenale, &c. II. Pesorbentes. The lateral lines have broad areas, about as thick as the musculature, without a vessel, and apparently suctorial. These forms do not, when mature, inhabit the food-canal of their host. Ex- amples:— Filaria tricuspis, Dracunculus medinensis, Eustrongylus gigas , &c., &c. III. Pleuromyarii. The lateral lines have neither cushions nor special lateral areas ; the oesophagus lumen is often a narrow chitinous tubule, and in some there is no intestine. Examples : — Trichocephalus unguiculatus, Gordius tolosanus, &c. The same paper includes a description of several new species. Excretory System of Nematodes.! — Prof. N. Nassonow has followed Kowalewsky’s injection method in studying the excretory organs of Ascaris megalocephala and Oxyuris flagellum. Powdered carmine or sepia injected into the cavity of the body of A. megalocephala is found aggregated in two pairs of giant stellate cells, connected with the lateral lines, and by irregular branches with the intestine. The lateral lines of Oxyuris flagellum consist of three rows of cells, the innermost cells being traversed by the excretory canal. Alleged Nematode-Parasites of Truffles.§ — M. J. Chatin examined a number of truffles (Tuber melanosporum and others) in which Nematodes occurred, and found that the worms were Pelodera strongyloides Schm. and Leptodera terricola Duj. ; that is to say, two saprophytic forms which had taken to a new habitat. They are not truly parasitic in the truffle, nor are they possible parasites of man. Molin’s Genus Globocephalus.|| — Dr. von Linstow has studied the intestinal parasite of the pig, to which Molin gave (1861) the name Globocephalus longemucronatus. His careful investigation shows that the parasite belongs to the genus Ankylostomum . * Journ. Quekett Micr. Club, vi. (1897) pp. 325-7 (1 pi.), t Arch. f. Mikr. Anat., xlix. (1897) pp. 608-22 (1 pi.). X Zool. Anzeig., xx. (1897) pp. 202-5 (3 figs.). § Comptes Bendus, cxxiv. (1897) pp. 903-5. il Zool. Anzeig., xx. (1897) pp. 184-7 (4 figs.). 290 SUMMARY OF CURRENT RESEARCHES RELATING TO Classification of Gordiidse.* * * § — Dr. F. Bomer describes Chordodes bara- mensis sp. n. from Borneo, out of a Mantid ( Hierodulci basalis ), Cli. com - pressus sp. n., also from Borneo, and C. moluccanus sp. n. from Halmahera. He proceeds to a taxonomic survey of the family, describing 16 well defined species of Gordius (with notes of 9 doubtful forms) and 16 well defined species of Gliordodes (with notes of 4 doubtful forms). Then follows a valuable diagnostic table. Gordius and Mantis.! — M. F. Lataste describes the emergence of a living specimen of Gordius chilensis from a wounded Mantis , its suspected host. Freshwater Nematodes of Hungary.! — Dr. E. v. Daday gives a list of no less than 64 species. Forty-two are confined to fresh water, six occur in damp earth and in fresh water, nine live solely in earth saturated with fresh water, six are restricted to earth saturated with fresh and brackish water, one is confined to earth saturated with brackish water. The list of strictly freshwater forms includes 12 found else- where in Europe, and 30 which are recorded from Hungary alone. Platyhehninthes. Development of Nemerteans.§ — Herr J. Lebedinsky describes the direct development of Tetrastemma vermiculus and Drepanophorus spec- tdbilis. The laid egg has two envelopes. It gives off two polar bodies, the first with four, the second with two chromosomes. One of them, pro- bably the first, divides again. They often get into the segmentation- cavity. The segmentation is total and approximately equal, and a segmenta- tion-cavity exists in the 8-cell stage. The resulting bipolar blastula becomes bilaterally symmetrical, an elongated oval with the upper pole turned to the anterior end and the lower pole to the posterior end. At the upper pole the cells multiply and form the head-gland-area ; at the lower pole is formed the endoderm area, bounded by four large round cells. The mesoderm is represented by four large round cells, the mother-cells of the body mesoderm. The bilaterally symmetrical blastula becomes an invaginated gastrula. A ^ear-shaped gut arises from an invagination of the endoderm area. Subsequently the gut-wall acquires several layers by the transverse division of the endoderm cells, and the gastric cavity is much reduced. In later stages the gut re-acquires its single-layered wall. The gut^ opens by the blastopore, and is connected therewith by a tubular process, the future caecum. The gut forms a diverticulum which communicates with the rectum. The blastopore, at first large, gradually decreases in size, moving forwards, and closes very late. As it closes, the tubular process of the gut separates from the ectoderm, and forms the caecum. The head-groove, or frontal organ, begins as a group of highly * Abh. Senckenberg. Ges., xxiii. (1897) pp. 250-95 (1 pi.), f Actes Soc. Scient. Chili, vi. (1896) pp. 71-3. j Zool. Jalirb. (Abth. Syst.), x. (1897) pp. 91-134 (4 pis.). § Arch. f. Mikr. Anat., xlix. (1897) pp. 503-56 (3 pis.); also pp. 623-50. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 291 vacuolated cells ; this rudiment is invaginated, and the cells bear a strong tuft of cilia ; subsequently the groove is gradually reduced in size. The head-gland begins as an area of round ectoderm cells ; these become cylindrical, and the area is invaginated, increasing in Tetrastemma , dwindling in Drejpanojphorus. A thickening of ectoderm is invaginated to form the proboscis. In Tetrastemma the invagination divides, a dorsal portion forming the pro- boscis, a ventral portion forming the secondary stomodaeum which communicates with the oesophagus. The oesophagus arises as a group of much elongated cells, which are invaginated and form a tubular cavity. In Tetrastemma this is con- stricted off from the ectoderm, and communicates with the secondary stomodaeum. The rectum is formed like the oesophagus, and communicates with the diverticulum of the gut. The four primitive mesoderm cells, which lie before and behind the blastopore, divide karyokinetically, and each forms a mesoderm band, which differentiates into a somatic and a splanchnic layer. The paired anterior mesoderm bands subsequently form an anterior (ventral) mesoderm sack ; the paired posterior mesoderm bands form a posterior (dorsal) mesoderm sack ; the two sacks unite ; the splanchnic layer clothes the gut, the somatic joins the ectoderm ; the cavity between is the body-cavity. The mesoderm of the proboscis arises from two mother-cells, which lie at first at the margin of the proboscis invagination, but subsequently migrate into the segmentation cavity. Each divides karyokinetically and forms a mesoderm band. Both of these differentiate into two layers with a cavity between. The bands envelop the proboscis and unite, the inner layer joining the proboscis, the outer forming the proboscis- sheath, with the rhynchocoelome between. The brain arises from two pairs of ectodermic thickenings, the dorsal and ventral ganglia. The ventral longitudinal strands arise from two thickenings of ectoderm, each connected with the corresponding ventral ganglion by a slight ectodermic thickening. Behind the dorsal ganglia the dorsal longitudinal strands arise in a similar manner, but they soon cease to elongate, and finally coalesce with the dorsal ganglia. The cerebral organs arise as invaginations of the ectoderm. The ectoderm is gradually differentiated into covering, flask-like, and other elements. In a continuation of the paper the author compares his results with those of others, and discusses the systematic position of the Nemertines. New Metanemerteans.* — Dr. T. H. Montgomery, jun., describes some American forms, beginning with Zygonemertes virescens Yerr. g. n. ( = Amphiporas virescens Yerr., 1892). The rhynchocoel extends to the posterior end of the body, while the thickened proboscis (with the exclu- sion of its retractor muscle) does not extend quite half the length of the rhynchocoel. The basis of the central stilet is very large, considerably elongated, flattened, or slightly concave posteriorly ; the basis is con- stricted near its posterior end. The central stilet is straight, massive, not half the length of its basis. There are ten or eleven longitudinal * Zool. Jakrb. (Abth. Syst.), x. (1897) pp. 1-14 (1 pi.). 292 SUMMARY OF CURRENT RESEARCHES RELATING TO proboscis nerves. A few elongated subepithelial gland-cells occur in the head region. Numerous small ocelli lie behind the brain on the dorsal and lateral aspects of the lateral nerve-cords. On these grounds this form has been separated from Ampliiporus. Mr. Montgomery also describes Proneurotes multioculatus g. et sp. n. The lateral nerve-cords unite posteriorly below the intestine about 1 mm. from the hind end ; both rhynchoccel and blood-vessels are continued for some distance behind the nerve-commissure, a condition which occurs in no other Metanemertean. Very characteristic are five unpaired diver- ticula of the voluminous rhynchocoel. It is otherwise, except in the very small size of its blood-vessels, related to Amphiporus. The author next describes Amphiporus greenmani sp. n., Tetrastemma jlagellatum sp. n., and has notes on some other forms which are not new. Nephridia of Stichostemma.* — Dr. T. H. Montgomery finds that the nephridia of Stichostemma eilhardi are very aberrant. Instead of one j)air there are several pairs, from the anterior to the posterior end, but all have not ducts. Other peculiarities are the following : The terminal bulbs have a closed cavity, not in open communication with the lumen of the ductules ; the presence of a closed cuticular structure immediately surrounding the cavity of the bulb, produced probably by the cells of the latter ; the probable absence of a ciliary flame within the cavity of the bulb ; the comparatively great length of the ductule connecting the bulb with the main ducts, and the absence of nuclei in its walls ; and the presence of a cuticula, of considerable thickness, on the epithelium of the main ducts. The explanation of these remarkable differences can probably be given only in terms of the adaptation of this descendant of marine ancestors to a life in fresh water. The occurrence of numerous separate nephridia cannot be regarded otherwise than as a secondary condition in Nemer- teans. Species of Ophryocotyle.f — Prof. A. Villot corrects some of the previous descriptions of this genus. The triple series of hooks is situated on the anterior margin of the sucker ; there are jive frontal suckers ; there may be over a hundred proglottides. As to species : — 0. proteus is quite distinct from 0. Lacazei , but 0. insignis Lonnberg is synonymous with 0. Lacazei. Trematodes of Freshwater Fishes.}: — Herr L. Hausmann has studied these in their faunistic and bionoinic relations. The following are some of his general conclusions. All kinds of fishes, whether vege- tarian or carnivorous, may be hosts of Trematodes ; but the carnivorous forms contain the sexually mature stages, the vegetarian forms usually the immature stages only, while those which live on microscopic animals may contain both stages. The number of parasites varies with the time of year, diminishing, for instance, in the cold season, when the fishes eat little. There are also fewer during the spawning season when the nutrition is slight. When a fish is brought into conditions of captivity, it tends to lose its parasites. The prevalent parasites vary somewhat * Zool. Jahrb. (Abtli. Anat.), x. (1897) pp. 265-76 (1 pi). t Zool. Anzeig., xx. (1897) pp. 197-9. % Rev. Suisse Zool., v. (1897) pp. 1-42 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 293 according to the habitat of the fish, a fact which probably depends upon the distribution of the intermediate hosts. There is an antagonism between different kinds of parasites, e. g. between Distomum and Echino - rhynchus ; and the number which one host can sustain seems to be limited. Experiments, like those made by Bunge, show that entoparasites require only a minimum oxygen supply. Iu the second part of his paper, Herr Hausmann describes a few new and rare species. Entozoic Tuberculous New Formations.* — Dr. Y. Diamare describes certain appearances in the internal organs of Thalassochelys caretta which are due to the presence of the ova of a small Distomum, Mesogonimus constrictus. The subserous tissue is studded all over with miliary no- dules attached to the blood-vessels of the gastric and intestinal perito- neum. A closer examination shows that an egg occupies the centre of the nodule, the ovum or its remains being surrounded by a zone of giant- cells, and the whole included in a fibrous investment. Two Forms of Distomum cygnoides.f — According to Dr. R. R. Bensley, it would seem that under the specific name cyynoides , Pagen- stecherand Loossliave confused two forms of Distomum. One form pos- sesses an ovary divided into several lobes, nine testes, of which five are on the same side of the body as the ovary, four on the opposite side, and a vitellogen subdivided into several small lobules. The other possesses an undivided reniform ovary, two testes, and a much simpler vitellogen. It also attains a greater size, and is provided with a relatively smaller ventral sucker. Eyes of Turbellaria and other Flat Worms.:} — Dr. R. Hesse finds great dissimilarity of structure even within narrow range ; thus the eye of Planaria torva , which is taken as a starting point, is almost as different from the eye of Euplanarians as from that of Polyclads and Nemertines. In all cases, however, the eye is composed of sensory cells, which on part of their course are surrounded by a pigment cup, and are at this region specially modified for the perception of light. Thus the end towards the cup may bear fine filaments or fibrillar rods. These optic cells are always so disposed that the sensitive ends are turned ctwaij from the entrant rays of light. The differences between the various types depend mainly on the number and modification of the optic cells. In the case of the simplest eyes with one optic cell or with only a few, no power of image -forming can be thought of as possible. Quantitative and qualitative differences of illumination may, however, be perceived. Even in the eyes of Dendroccelum and Eujplanaria image-forming is not probable ; for, owing to the arrangement of the optic elements, a ray must in many cases meet several elements. In Polyclads only do the rods lie in one plane, but they are not separated by pigment sheaths, and image- forming is very improbable. The author describes numerous types in detail. Remarkable new Planarian.§ — Dr. A. Willey found at Lifu a new type of Planarian, which he calls Heteroplana Newtoni. It presents * Centralbl. f. Bakt. u. Par., lte Abt., xxi. (1897) pp. 459-65. t Tom. cit., pp. 326-31 (1 pi.). X Zeitschr. f. wiss. Zool., lxii. (1897) pp. 527-82 (2 pis , 3 figs.). • § Quart. Joum. Micr. Sci., xl. (1897) pp. 203-5 (1 fi PP- 145-87 (4 pis.). § Tom. cit., pp. 321-45 (2 pis.). 11 Bull. Acad. Imp. St. Petersbourg, iv. (1896) pp. 389-408 (1 pi.). ^ Abb. Senckenberg. Nat. Gesellsch., xxiii. (1897) pp. 297-318 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 299 Another feature is the enormous size, as seen in Hebella contorta and H. scandens. Many forms are symbiotic ; thus, on Acanthella effusa there sits a Sertulariau, and on both Hebella contorta grows. Ampullae in Millepora.* * * § — Prof. S. J. Hickson has found these cavities (in which he discovered a male medusiform gonophore in 1890), not only in Millepora Murrayi , but in other museum specimens, labelled M. Schrammi , M. alcicornis , M. complanata. Porifera. Lithonina.t — Prof. L. Doderlein describes Petrostroma Schulzei, re- presenting a new group of Calcareous Sponges (Lithonina). The new form is Millepore-like or Polyzoon-like, and was found in deep water (200-400 m.) off the Japanese island of Enoshima. Only dry specimens were studied. The cortical layer consists of numerous free tetracts and triacts, besides dense bundles of peculiar forked spicules. In the deeper portions a connected framework has been formed by the fusion of tetracts with plump arms. It presents marked resemblances to the fossil Phare- trones, which are the only known calcareous sponges with a coherent skeleton. With these Dendyhas also associated Lelapia australis Carter, in which forked spicules are united in rigid strands. But Doderlein points out that, in spite of the likeness of Petrostroma to certain Phare- trones, there is this great difference, that in the latter the spicules are united in bundles by some cementing substance, while in this new form a real fusion of spicules has occurred. Protozoa. Physiology of the Cell.J — Dr. M. Verworn has continued his inter- esting observations and experiments on Protozoa. He has studied the phenomena of contractility and irritability in Eed Sea Phizopods — Orbitolites complanatus , Amphistegina Lessonii, Hijalopus ( Gromia ), Du- jardinii , and a new form, Phizoplasma Kaiseri. Among his conclusions we note the following : — (a) The transport of plasmic material in the cell is quite distinct irom the propagation of a stimulus ; (6) removal of oxygen acts first on the expansion of pseudopodia, secondly on their retraction, and ends in inducing paralysis of both ; (c) the change from positive to negative thermotropism after a certain temperature is exceeded is due to the fact that the expansion and retraction phases have different limits. At 30°-32° C. for Phizoplasma the expansion and retraction phase are equally stimulated ; below this optimum of movement the ex- pansion phase is most strongly stimulated, above the same optimum the contraction phase is most stimulated. New Flagellata.§ — Herr Hs. Meyer describes the following new species: — Mastigamceba commutans, Dimorpha digitalis , D. bodo, Monas minima , M. amoebina , 31. sociabilis , Ochromonas tenera, O. granulosa, O. variabilis, and O. chromata. He also gives useful diagnoses of the * Mem. and Proc. Manchester Lit. Phil. Soc., xli. part 2 (1897) Mem. 5, pp. 1-4. t Zool. Jahrb. (Abth. Syst.), x. (1897) pp. 15-32 (5 pis.). t SB. Akad. Wiss. Berlin, 1896, pp. 1243-54. § Rev. Suisse Zool., v. (1897) pp. 43-89 (2 pis.). 300 SUMMARY OF CURRENT RESEARCHES RELATING TO securely defined species in these four genera, and briefly discusses the Flagellata in general. Protozoa of Salt Lakes.* — Dr. P. Butschinsky has studied the Pro- tozoa found in two salt lakes or Limans near Odessa. They are more abundant in the lake with the less salinity, and they consist partly of freshwater and partly of marine species. The fauna of the two lakes is not the same, and in both cases very striking fluctuations occur. New Radioiarian.f — Herr W. Karawaiew has secured another speci- men of the remarkably simple new Eadiolarian which he described last year, from Villafranca.J It has six diametral spicules in pairs, and is a spherical cell with a delicate external pellicle covered with minute papilliform elevations. New Holotrichous Infusorian.§ — Herr M. Rimsky-Korsakow de- scribes Dinobrya cylindrica sp. n., found in the water tank of the Zoo- logical Institute of St. Petersburg. The position of the mouth, the general shape, the ciliation, &c., point to its being a species of Dinobrya, of which D. LieberJdihni has been hitherto the only named form, though Lieberkiihn and Eberhardt seem both to have observed the species under discussion. It differs from D. LieberJdihni in its cylindrical shape, in having 1G rows of 20-22 cilia instead of 20 rows of 16-18, and in the shape of the macro-nucleus, which is not spherical but slightly horse-shoe-shaped. The author refers the genus, as Schewiakoff does, to the family Cyclodina, in which it represents a fiist stage in the ten- dency to reduction of cilia. Species of Trichodina.|j — Herr Hs. Wallengren describes Trichodina pediculus Ehrenberg, which he found on Gastrosteus punzitius and other freshwater fishes, as Zvennerstadt also did. The same form was found by H. James-Clark on Hydra, and minutely described. The previous description is in part amplified and in part corrected by Wallengren. He also describes Trichodina miira v. Siebold from Planaria lugubris. New Gregarine.^ — MM. A. Labbe and E. G. Racovitza describe Pterospora maldaneorum g. et sp. n., parasitic in Leiocephalus leiopygos and (?) Clymene lumbricoides at Roscoff. It is an acephalous pyriform Monocystid, with two groups of four digitiform retractile prolongations at the narrow end. Two individuals always occur together, united by the swollen ends. Spherical or oval cysts are formed after the encap- suling of two individuals. They do not sporulate separately. The cysts dehisce by simple rupture. The spores have dissimilar poles and eight (?) falciform sporozoites. Coccidia of Myriopods.** — M. L. Leger finds in Lithobius impressus a new polysporous monozoic Coccidian parasite, allied to Barroussia. The genus Coccidium , characterised by a strong tetrasporous cyst with dizoic spores, is not quite confined to Vertebrates, as is usually believed ; * Zool. Anzeig., xx. (1897) pp. 194-7. t Tom. cit., pp. 190-4. t Cf. this Journal, 189G, p. 427. § Biol. Ceutralbl., xvii. (1897) pp. 257-60 (1 fig.). i| Tom. cit., pp. 55-G5 (6 figs.). *1 Bull. Soe. Zool. France, xxii. (1897) pp. 92-7 (4 figs.). ** Comptcs Rcntlus, exxiv. (1897) pp. 901-3. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 301 it is frequently represented in Centipedes. As to the trisporous forms and the genus Bananella of M. Labbe, an abortion of one of the tetra- spores of the Coccidium- type may be sufficient explanation. Life-Cycle of Coceidia.* — M. Louis Leger has studied various Coc- cidian parasites in Myriopods and Insects, and has come to the conclu- sion that in Arthropods the genus Eimeria does not represent a distinct parasite, but rather a stage in the life-cycle of a Coccidian. There seems to be no ease known in which an Arthropod with Coccidia does not also include phases of an “ Eimerian ” cycle. The life-history of a Coccidian may thus be summed up : — “ Eimerian sporozoite, encapsuled form, tetrasporous cyst (Coccidian), coccidian sporozoite (penetrating into the host), Eimerian budding, and then the Eimerian sporozoite again.” The author proposes to show that the Eimerian sporozoite corresponds to the sporoblast of Gregarines, and the tetrasporous cyst of a Coccidian to the spore of Gregarines. * Comptes Rendus, cxxiv. (1897) pp. 966-9. 302 SUMMARY OF CURRENT RESEARCHES RELATING TO BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-Structure and_Protoplasm. Influence of the Nucleus on the Formation of the Cell-wall.* — Prof. W. Pfeffer contests the statement of Palla f that an isolated non- nucleated mass of cytoplasm can form a cell- wall. This erroneous obser- vation has arisen from overlooking connecting threads of protoplasm. From observations made on rhizoids and leaves of mosses, prothallia, Clfiara , leaves and hairs of flowering plants, pollen-tubes, &c., it would appear that the irritation necessary for the formation of a cell- wall is caused by the extremely fine protoplasm filaments which 'pass through the cell-wall and which constitute a living connection between neigh- bouring protoplasts. The same function belongs to masses of cyto- plasm which lie in close apposition to a cell-wall, and which there- fore maintain their connection with the protoplasmic filaments of tho neighbouring cells. The existence and healthy life of an organism are dependent on the co-operation of the nucleus and cytoplasm. Chromatin-reduction and Tetrad-formation in Pteridophyta.f — Mr. G. N. Calkins describes the following phenomena in the formation of spores in Pteris tremula and Adiantum cuneaium , tracing their analogy to the corresponding processes in animals. The process of spore-forma- tion can be divided into the three periods of division, growth, and matura- tion. The division period is the interval between the archespore and the 16-cell stage of the sporange. The growth period is the interval during which the 16 cells enlarge, and tetrads are formed. The maturation period includes thejjwo successive divisions of the nuclei in the 16-cell stage and the formation of the spores. The cells of the division period are commonly known as the archesporial cells. For those of the growth-period the author proposes to replace the term spore-mother-cell by primary sporocyte, using also secondary sporocyte for the daughter-cells of the primary sporocyte. In the growth-period the chromatin forms a delicate moniliform spireme before the nucleole has disappeared. A much thicker spireme is subsequently formed from this moniliform thread. The thickened spireme then splits longitudinally. It next breaks up into half as many double spireme-segments as there are chromosomes in the somatic cells ; each of these double elements forms a tetrad. Three types of tetrad-formation are found in each nucleus — the rod type, the ring type, and the cross type. In all three types, the tetrads are finally formed by a transverse division of the halves of the double spireme -segment. Cell-Hypertrophies produced by Galls.§ — M. M. Molliard describes the pathological hypertrophy of cells caused by the attacks of species of * Ber. K. Sachs. Ges. Wiss. Leipzig, 1896 (1897) pp. 505-12. f Cf. this Journal, 1890, p. 475. i Bull. Torrey Bot. Club, xxiv. (1897) pp. 101-15 (2 pis.). § Kev. Gen. de Bot. (Bonnier), ix. (1897) pp. 33-44 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 303 Phytoptideae on Geranium sangnineum, G. dissedum, species of Bromus , and Galium Mollugo , The changes which take place in the nucleus are especially striking. It is frequently increased enormously in size ; and, in addition to the normal nucleole, contains a number of accessory or pseudo-nucleoles. In many of the cells attacked there are also bodies having the appearance of secondary nuclei. The nucleus frequently divides by simple constriction, without mitosis, or by a process of budding. (2) Other dell- Contents (including1 Secretions). Oil in Leaves.* — According to researches made by Herr S. Rywosck on deciduous and evergreen flowering plants, Muscineae, and Algae, the oil contained in leaves (or other green organs) has an entirely different function from the oil contained in the stem, and cannot be regarded as a reserve food-material. Instead of being stored up in the winter and disappearing when the period of vegetative activity recommences, it remains, and even increases in amount, during the spring and summer, being very large even when the leaves have turned yellow in autumn. Its purpose appears to be to take up the xantliophyli. The diameter of the oil-drops usually varies between 5 and 18 /x, and there are most commonly several in a cell. The chemical nature of the oil, whether it belongs to the fatty or to the essential series, was not determined. Volatile Reducing Substance in Green Cells.*)* — Herren T. Curtins and J. Reinke discuss the nature of the volatile reducing substance which is the first product of assimilation in green cells, and which they decide to be of the nature of an aldehyd. They propose for it the formula C7HuO.CHO, or occasionally C7H9O.CHO. Further details are given with regard to its chemical and physical properties. Tannins in Fruits, f — From experiments made chiefly on the fruit of Biospyros, M. C. Gerber concludes that one object of the presence of tannins in fruits is to prevent the formation of pectic substances, and hence the fermentation of their saccharine contents. The tannins finally disappear by oxidation, without giving rise to carbohydrates. Production of Hydrocyanic Acid in the Pome8e.§ — M. L. Lutz states that amygdalin and emulsin are present in the seeds of plants belonging to the genera Malus, Cydonia, and Sorbus, but not in those of Pyrus , Mespilus , and Cratsegus. In the Pomeae emulsin was found in the paren- chymatous cells of the cotyledons, especially in the neighbourhood of the vascular bundles, but not in the palisade-cells ; none was found in the hypocotyl, plumule, or radicle. Amygdalin occurs in the cells of the cotyledons which contain emulsin, trituration giving rise to the odour of bitter almonds ; it is also present in the hypocotyl, plumule, and radicle. (3) Structure of Tissues. Leptome of Angiosperms.]! — Herr F. Czapek describes the highly differentiated leptome of Angiosperms as consisting of three distinct physiologico-anatomical tissue-systems, viz. : — (1) The transport system, * Ber. Deutscli. Bot. Gesell., xv. (1S97) pp. 195-200. f Tom. cit., pp. 201-10. X Comptes Rendus, cxxiv. (1897) pp. 1100-8. § Bull. Soc. Bot. France, xliv. (1897) pp. 26-82. || Ber. Deutscli. Bot. Gesell., xv. (1897) pp. 124-31. 304 SUMMARY OF CURRENT RESEARCHES RELATING TO composed of the sieve-tubes and the traces of the cambiform cells ; (2) The absorption- system, consisting of the companion-cells, whose func- tion is to take up the substances transported in the sieve-tubes, or to carry formative materials from the storing tissue, and to transfer them to the sieve-tubes ; (3) The storing system, represented by the longitu- dinal parenchyme-traces of the leptome and by the leptome medullary rays, which store up in themselves the assimilated substances. The characteristic function of the leptome of the l^igher plants is the trans- port of both nitrogenous and non- nitrogenous formative materials ; the conduction of the carbohydrates and oils taking place chiefly through the sieve-tubes and cambiform traces. Formation of Periderm and Epiderm.* — From a series of experiments made by imbedding in gypsum on a number of different plants, Herr H. Tittmann finds a marked difference in their power of regeneration between the periderm and the epiderm. A regeneration of the periderm was found to take place in many cases under favourable circumstances, but not of the epiderm. The cuticle is, however, frequently re-formed afresh. A power of regenerating the layer of wax exists in some plants, but not in others. The process is independent of light. Cork-Growths.f — Sig. E. Matteucci discusses the various kinds of cork-growth found in the leaves and other organs of plants, and classifies them, after Bachmann,J under two types, passing into one another by insensible gradations. In the first the cork-growth forms a prominent excrescence on the surface of the leaf, the cells being arranged in regular rows, with their walls parallel to the surface of the leaf. In the second type it extends deeper into the tissues of the leaf, and is of a spherical or hemispherical form, the cells arranged in rows radiating from the centre. The first type was the more frequent in the plants examined by the author. He supports the view of Bachmann and Borzi that these struc- tures are morphologically and physiologically of the nature of lenticels. Supernumerary Vascular Bundle in a Root.§ — Hr. E. Paratore calls attention to the occurrence of this rare phenomenon in a secondary root of Daphne melanoplithalmus. The bundle is intercalated between the elements of the secondary phloem, and was composed, in the example examined, of four dotted vessels, formed by the special activity of cambi- form cells of the secondary phloem, and directly from cambial cells. Anatomy of Chrysobalanese.|| — Dr. E. Kiister describes the minute anptomy of a number of genera and species of this order, with special reference to the deposition of silica. This deposition of silica is, as a rule, strictly localised. In the greater number of genera the cell- walls are strongly silicified, and there are in addition minute granules of silica deposited within the cell. These occur in the leaves, especially in the neighbourhood of the veins, and in the axis. Other points of structure are also treated of in detail. In another paper ^ the author gives further particulars of the charac- * Jahrb. f. wiss. Bot. (Pfeifer u. Strasburger), xxx. (1897) pp. 11(3-51. t Nuov. Giorn. Bot. Ital., iv. (1897) pp. 224-43. J Cf. this Journal, 1881, p. 74. § Malpighia, xi. (1897) pp. 82-4. I! Bot. Centralbl., Ixix. (1897) pp. 46-54, 98-106, 129-39, 161-9, 193-202,225-34 (1 pb)* * Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 134 8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 305 teristics of the two modes of deposition of silica, which he terms t: Kieselkorper ” and “ Kieselfiillungen.” The latter agree in character with the peculiar “ tabaschir ” of the Bambusese. Structure of Diapensacese.* * * § — Herr W. Grevel describes the anato- mical and histological structure of several species belonging to this order of Ericales. Among the general characteristics of the order is the entire absence of secondary medullary rays in the stem. The primary vessels have, as a rule, but slightly thickened walls. The epidermal cells of the leaves- have always wavy walls. The elements of the xylem, except the primary annular vessels, have, for the most part, bordered pits. No mycorhiza could be detected in the roots. The points of resemblance and difference with the allied orders of Ericales are pointed out. Anatomy of Cissus gongylodes.f — M. H. Jumelle describes in detail the structure of this remarkable climber from Brazil, belonging to the Ampelidese, of which the most striking characters are the broad winged stem, the red aerial roots springing from the nodes, and the tubercles formed at the ends of the branches, which become detached and serve to propagate the plant. These tubercles are modified internodes, in which are stored up large quantities of food-materials, especially starch and mucilage, The aerial roots, if uninjured, remain unbranched until they reach the soil, when they branch copiously. The exposure to the air has a tendency to increase the thickness of the central cylinder, with an increase of the size of the pith and of the medullary rays. In the light there is a large formation of calcium oxalate. (4) Structure of Organs. Influence of the Soil on the Colour of Flowers.^ — Herr H. Molisch has experimented on the influence of the chemical composition of the soil in changing the natural pink colour of the flowers of Hydrangea liortensis to blue. He finds that this change is invariably brought about by the presence of alum in the soil, and that the efficient constituent in the alum is aluminium sulphate, which has the same effect as alum. Ferric sulphate has a similar effect ; while the result with other salts of iron was mostly negative. The blue colour is due to a chemical combi- nation of the salts in question with the anthocyan, which is the cause of the natural red colour of the flowers. The most sensitive part of the flower to the change in colour is the filament. Homology of the AntherJ — According to M. D. Clos, the filament of the stamen only very rarely represents the petiole of a leaf. In most Apopetalie it corresponds to a linear petal, to the median veinr to a narrow longitudinal band of a broad sessile petal (Ranunculaceae, Berberidese), or to the claw of an unguiculate petal (Sileneae, many Cru- ciferae). In the Apopetalte with polyadelphous stamens the staminal vessels are very frequently analogous to the veins of the petals, the number of these very often corresponding to that of the staminal phalanges. The anther, whether sessile, dorsifixed, or basifixed, is a * Bot. Centralbl., Ixix. (1897) pp. 257-67, 309-15, 312-7, 369-77, 401-11^(1 pi.). t Rev. Gen. de Bot. (Bonnier), ix. (1897) pp. 129-19 (8 figs.). X Bot. Ztg., lv. (1897) lte Abt., pp. 49-61. § Comptes Rendus, exxiv. (1897) pp. 808-10. 306 SUMMARY OF CURRENT RESEARCHES RELATING TO structure without analogy among vegetable organisms. It finds its nearest equivalent in the nucellus of the ovule ; both structures being necessitated by their sexual functions. The author further reminds botanists that he had anticipated van Tieghem in pointing out that in Lepidoceras (Loranthacese) the ovary is destitute of ovules, and that Decaisne had still earlier called attention to the absence of an ovarian cavity in the mistletoe. Ovary of the Pomegranate.* * * § — M. L. Gaucher describes the struc- ture and development of the ovary of Punica Granatum. The chief peculiarity is that, in the course of development of the ovary, the recep- tacle undergoes a remarkable hypertrophy by which the loculi, at first horizontal, become basilar, and the axile placentation assumes the appearance of being parietal. An inferior row of three loculi is then formed below the original five ovarian cavities. Ovule of Christisonia.* — Mr. W. C. Worsdell has followed out in detail the development of the ovule in this genus of Orobanchese, and finds that it differs in no important respect from that in Orobanche. No tapetal cells were seen to be cut off from the archesporial cell. This cell first divides by a transverse wall into two equivalent cells. Each of these cells then divides again, so forming a row of four cells. Of these the hindermost, the one furthest from the apex of the ovule, alone increases in size, and gradually crushes and absorbs the three others. This is the young embryo-sac. Seeds of Papilionacese.J — Reverting to the structure of the seeds of Vicia narbonensis , Sig. L. Macchiati disputes the statement that they present no peculiarities of structure as compared with other allied species. The “twin tubercles” in the seeds of the Papilionacefe are not correctly described as identical with a strophiole, although in many Phaseoleae they present the appearance of two small projecting papillae. In Vicia Faba the strophiole is rudimentary. Symmetry of the Appendicular Organs. § — M. A. Chatin calls attention to the importance of the symmetry of the appendicular organs as an indication of the degree of organisation. The general superiority of the Dicotyledones to the Monocotyledones is indicated by the rarity of verticillate leaves and the very frequent absence of a corolla in the latter. Among Dicotyledones a lower stage is indicated by the spiral arrangement of the carpels in some orders of Thalamiflorae (Ranuncu- laceae). Further indications of a high type of structure are presented by the twisted or valvate aestivation of the corolla and the valvate aestivation of the calyx in some orders of Dicotyledones. Red Spots on Leaves. [| — Sig. G. Mattej has investigated the nature of the red spots on the foliage-leaves, petals, and other organs of many plants, 3Iyrsine, Lysimachici, Oxalis, &c. The pigment is composed essentially of a gum-resinous substance, coloured by a yellowish-red essential oil, its chemical constitution varying in different cases. They * Journ. de Bot. (Morot), xi. (1897) pp. 121-4 (7 figs.). f Journ. Linn. Soc. (Bot.), xxxi. (1897) pp. 576-84 (3 pis.). X Bull. Soc. Bot. Ital., 1897, pp. 104-10. Cf. this Journal, 1893, p. 62. § Comptes Rendus, cxxiv. (1897) pp. 1061-8. || Bull. Soc. Bot. Ital., 1897, pp. 83-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 307 are not, as a rule, found in tlie earliest stages of the development of the organ, and are evidently formed by transformation from leucites. They arc often surrounded by a membrane, and are always imbedded in the parenchyme, and surrounded by ordinary cells. Dimorphic Branches of Castilloa.* * * § — M. F. A. F. C. Went describes the peculiar habits of Castilloa elastica , a native of Java, belonging to the Urticaceae, of producing, in addition to the ordinary branches, others which are cast off. These branches differ from the ordinary ones in their phyllotaxis, and bear no leaf-buds, although they may produce inflorescences in their leaf-axils. When the deciduous branches are thrown off, they leave a hollow in the stem. The purpose of the arrangement appears to be that the tree may form a crown of leaves at the summit of the stem. Scales of the Bulbs of Allium.f — Dr. I. Baldrati discusses the morphological character of the hard scales found in the bulbs of certain species of Allium ( [neajpolitanum , Chamsemoly , roseum ), and determines them to be of an essentially foliar nature. They are always provided with a sclerotic stratum, and appear to serve a protective purpose to the remainder of the bulb. In A. nigrum all the stages of transformation can be followed, from the ordinary leaves to these fleshy structures, the green tissue being the first to disappear. Underground Runners.^; — From observations made chiefly on Enj - tlironium americanum and Arissema tripliyllum , Miss Ida A. Keller con- cludes that the production of underground runners or stolons in plants which possess these organs is in inverse proportion to the energy ex- pended in the production of fruit and seeds. Contractile Roots of Arum.§ — Herr A. Rimbach describes the con- tractile roots which appear on the two-year-old rhizomes of Arum maculatum. The contractility is confined to the basal portion of the root, and may amount to as much as 50 per cent, of the length of this portion. The tendency is to drag the growing point further and further below the surface. A contraction to the extent of 18 mm. was measured on one root. On a mature rhizome only about one-half of the roots are contractile, and these are about double the diameter of the non-contractile ones. The contractile tissue is the cortical parenchyme ; the central vascular cylinder and the outermost part of the cortex remaining passive. Evolution of the Cyclamen.|| — Mr. W. T. Thiselton-Dyer traces the development under culture of the various varieties of the Cyclamen from C.persicum ; the most remarkable forms consisting in the fimbriation of the petals and in the appearance of a plumose crest on each petal. The author regards the general tendency of a plant varying freely under artificial conditions to be atavistic, i.e. to shed adaptive modifications which have ceased to be useful, reverting to a more general type. * Ann. Jard. Bot. Buiteuzorg, xiv. (1896) pp. 1-16 (3 pis.). t Nuov. Giorn. Bot. Ital., iv. (1897) pp. 214-23 (1 pi.). X Proc. Acad. Nat. Sci. Philadelphia, 1897, pp. 161-5 (1 pi.). § Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 178-82 (1 pi.). 11 Proc. Roy. Soc., lxi. (1897) pp. 135-47 (10 figs.) ; Nature, lvi. (1897) pp. 65-8 (10 figs.). 308 SUMMARY OF CURRENT RESEARCHES RELATING TO Structure and Affinities of the Grubbiaceae.* — M. P. van Tieghcm points out that this small order, composed of the two genera Grubbia and OpMra, usually included in, or placed near, the Santalaceae, is not really nearly allied to that family. The bilocular ovary contains a true seed,, and the order must be placed among the unitegminate apopetalous Seminatae with inferior ovary ; its nearest ally is the Bruniaceae. The structure of the anther presents a fortuitous resemblance to that of the Hamamelideae. Vegetable Teratology. j — M. C. de Candolle classifies the various examples of vegetable teratology under two heads, ataxinomic and taxi- nomic. The former includes such abnormal structures as are not repre- sented among plants in a normal condition, for example fasciation, torsion, chloranthy (when it does not result from the action of parasites), doubling of flowers (when resulting from the substitution of petals for stamens and carpels), and other less common abnormalities. The latter class comprises those abnormalities which correspond to taxinomic differ- ences between species, such as the concrescence of leaf-sheaths usually distinct, the transformation of leaves or leaf-sheaths into pitchers, the formation of emergences or supernumerary laminse, proliferation, the concrescence of cotyledons, synanthy, peloria, the arrest or abortion of some of the floral whorls, &c. The author points out that the general tendency of teratological structures is towards a greater simplicity of development. £. Physiology. (1) Reproduction, and Embryology. Embryogeny of Veronica.^ — Prof. A. Meunier has followed out the process of impregnation and the changes which take place during the development of the endosperm and the growth of the embryo and of the seed, in several species of Veronica. The embryo-sac is derived from the hypodermal cell at the summit of the ovule, the nucleus of which at once undergoes its first bipartition, followed, with great rapidity, by fresh divisions. When the pollen-tube enters the embryo-sac, the male nucleus penetrates the substance of one of the synergids, afterwards passing into the oosphere. After impregnation lias taken place, the embryo-sac becomes completely divided into two parts by a constriction ; the lowermost of these portions (which contains the antipodals) taking no part in the formation of the endosperm ; and the same is the case with a portion which is divided off at the micropylar end of the sac. Of the eight nuclei which result from the third bipartition of the primary nucleus of the embryo-sac, only two take part in the formation of the endosperm, four remaining in the chalazal, and two in the micropylar portions of the sac, in which no endosperm is formed. The variations in the further development of the embryo and of the seed are traced out in Veronica hedersefolia, agrestis, jjersica, triphjllos , and arvensis. * Journ. de Bot. (Morot), xi. (1897) pp. 127-38. t Arch. Sci. Phys. et Nat., iii. (1897) pp. 197-208. X La Cellule, xii. (1897) pp. 297-334 (2 pis.). Cf. this Journal, 1894, p. 225. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 309 Embryogeny of Salix.* — Mr. C. J. Chamberlain has followed out the development of the male and female organs and the process of im- pregnation in several American species of Salix. In the development of the pollen-grains, the division of the original nucleus into generative and pollen-tube nucleus takes place before the breakdown of the tapete. There is no dividing wrall between the nuclei, as is the case in Populus. The cells of the tapete often contain two nuclei. The embryo-sac originates in a hypodermal cell at the apex of the nucellus. There are sometimes two or three archesporial cells, but it is rare for more than one to develop. The primary tapetal cell usually gives rise to a tier of three or four cells, but sometimes does not divide. The first division of the primary division of the embryo-sac is transverse. The antipodals apparently disappear at a very early period. The synergids have fre- quently a strongly developed “ filiform apparatus.” The egg-apparatus breaks through the wall of the embryo-sac, and projects into the micro- pyle. No tendency to chalazogamy could be detected, the pollen-tubes always entering the embryo-sac through the micropyle. The first division of the fertilised oosphere is always transverse ; the second division is usually longitudinal, but sometimes transverse ; the third is at right angles to the second. Embryogeny of Conifers.! — Prof. J. M. Coulter publishes notes of a number of observations on the impregnation and embryogeny of Conifers, among which are the following : — In Pinus Bariksiana there was observed, after the entrance of the apex of the pollen-tube into the oosphere, a peculiar bulging of the larger (female) in the direction of the smaller (male) nucleus, before conjugation. In P. Laricio a single embryo is frequently developed at the end of two, or even of four sus- pensors; occasionally two embryos at the end of a single suspensor. In P. Banksiana it appears to be the rule for the first one or two .segmentations to be transverse. Pollination by Bats.{— -Mr. J. H. Hart states that the flowers of Bauhinia magalandra sp.n., a large tree native of Trinidad, are pollinated by the agency of bats. The flower is white and strongly scented, and opens only in the evening, when it is visited by several species of bat, apparently not in search of the nectar, but of the insects which are attracted to the flower by its odour. They alight upon and hold fast to the protruded stamens, and appear to attack the erect and recurved petals, which are often completely destroyed ; and in so doing carry the pollen from the anthers to the stigma. Fertilisation of Spring Flowers.§— Mr. J. H. Burrill records the results of a long series of observations on the fertilisation of spring flowers on the Yorkshire coast, with a careful record of the visiting insects observed. As a general result he states that short-tongued flies predominate in early spring, and that they visit freely flowers with honey, whether hidden or exposed. Some early flowering species appear to derive no advantage from this precocity. Thus Cajpsella bursa-pastoris * Bot. Gazette, xxiii. (1897) pp. 147-79 (7 pis. and 1 fig.). t Bot. Gazette, xxiii. (1897) pp. 40-8 (l pi. and 1 fig.). t Bull. Misc. Information R. Bot. Gar, den Trinidad, iii. (1897) No. 10, pp. 30-1. § Jouru. of Bot., xxxv. (1897) pp. 92-9, 138-45, 184-9. 1897 Y 310 SUMMARY OF CURRENT RESEARCHES RELATING TO frequently lias abortive stamens ; Ranunculus Ficaria is generally infer- tile ; Petasites vulgaris is nearly always male ; TJlex eurojpseus and Primula vulgaris set but little fruit. In other cases the advantage of the early flowering is clearly in the flowers opening before the appearance of the leaves, which obstruct pollination, whether by wind or by insects. Germination of Pollen-Grains.* * * §— Prof. A. Hansgirg contests the opinion of Lindforss,! that those plants the pollen- grains of which perish in water, have their anthers and their stigmas protected in the flowers against the access of rain. He gives two long lists of plants whose pollen germinates readily in pure water ; one of these lists being of species whose sexual organs are protected against rain, while in those of the other list there is no such protection. In a very large number of other plants the pollen-grains either do not germinate in water, or only with great difficulty. (2) Nutrition and Growth, (including: Germination, and Movements of Fluids). Assimilating Energy of the Blue and Violet Bays of the Spec- trum.:]:—As the result of a series of experiments, chiefly on Elodea ( Anacharis ), Herr F. G. Kohl states the following general conclusions as to the part taken by the different rays of the solar spectrum in the evolution of oxygen from leaves. The assimilating energy of the red rays is about one-half that of undecomposed sunlight. The action of the blue rays is but little less than that of the reel. The amount of oxygen given off in the green rays is not more than half that in the blue. The energy of the yellow rays is less, and that of the violet least of all. The author distrusts both the eudiometric method of measuring the energy of the process of assimilation, and the bacterium method of Engelmann. He prefers the results obtained by counting the bubbles of oxygen given off, and describes a process by which the actual volume of gas thus eliminated can be determined. Beciprocal Influence of Stock and Graft on one another.§ — M. L. Daniel records the results of grafting Heliantlms annuus (annual and few-flowered) on H. Isetiflorus (perennial and many-flowered) and vice versa. He finds a direct reciprocal influence of stock and graft. The predominant effect of the stock is on the form of the assimilating tissue of the graft ; it is also manifested in the flowering ; the graft exercises an influence especially on the mode and duration of the development of the stock. In the passage of species of Helianthus to the latent state there may possibly be a substitution between lignification and the for- mation of tubers. Influence of Chemical Beagents and of Light on Germination.il— Dr. A. J. J. Vandervelde states that all chemical reagents used (salts of potassium, sodium, ammonium, barium, strontium, iron, and copper) have a prejudicial influence on the germination of seeds. Nitrates are more * Oesterr. Bot. Zeitschr., xlvii. (1897) pp. 48-52. Cf. this Journal, ante, p. 138. + Cf. this Journal, 1896, p. 437. i Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 111-24 (3 figs.). § Comptes Rendus, exxiv. (1897) pp. 866-8. [|| Bot. Centralbl., Ixix. (1897) pp. 337-42. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 311 injurious than chlorides ; sulphates less injurious than either. Salts of barium and strontium are less prejudicial than those of calcium. Potas- sium chromate and bichromate, cupric sulphate, and ferric sulphate, are especially poisonous. Light appears to have no influence on the germination of seeds. Influence of Light on Dorsiventral Organs.* * * § — From observations made by Miss K. C. Burnett on leaves of Salix alba , it appears that when palisade tissue has once been formed on the surface of a leaf exposed to light, it cannot be changed, but that the parenchymatous tissue of the under surface, if exposed for a sufficiently long time to the action of light, will take on the characteristics of palisade tissue. Gemmae of Lunularia will develop rhizoids on the morphologically upper surface when placed in contact with the soil, but only when the gemma is in a very young stage of development. Assimilatory Inhibition.j* — From a further series of observations made on a variety of plants, Dr. A. J. Ewart states that chloroplastids developed in darkness, whether they become green or are etiolated, may possess a fairly active power of assimilation corresponding to their size and depth of colour. The power of assimilation is absent whilst the etiolated leaf is quite young, and finally disappears again after the leaf has been kept for a long time in darkness. Etiolated leaves exposed to light in an atmosphere entirely deprived of C02 turn green, and may acquire an active power of assimilation, which, however, soon begins to weaken, and is in most cases rapidly lost. From experiments on CJiara he finds that cells from which nearly all the chloroplastids had escaped could nevertheless still remain living, though incapable of regenerating fresh chlorophyll, for a period of a year. Biology of Woody Plants.J — Herr K. Reiche has investigated the structure and physiology of the wood of many plants belonging to widely separated natural orders, natives of Chile. He finds that the evergreen and the deciduous condition pass into one another by insensible gradations. They can, however, be classified into those which display an. uninterrupted increase in thickness, and those in which the increase in^ thickness is periodically interrupted by periods of repose. The activity which brings about the increase in thickness precedes the unfolding of the leaves. When first formed, the new tissue is free from starch, while it' is found abundantly up to the close of the previous period of growth. Regeneration of Split Roots. § — As the result of experiments on plants belonging to widely separated natural orders — Zea Mays , Vicia Faba , Philodendron robustum, &c. — Herr G. Lopriore states that the regeneration of split roots always takes place by apical growth, the exact process being greatly dependent on the mode in which the section has been made. Regeneration may take place in all the tissues, — epiderm, cortex, and vascular system. A healing-tissue is formed in the inter- * Bull. Torrey Bot. Club, xxiv. (1897) pp. 116-21 (1 pi.). t Journ. Linn. Soc. (Bot.), xxxi. (1897) pp. 554-76. Cf. this Journal, 1896, p. 649. % Jakrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 81-115. § Abhandl. K. Leopold.-Carol. Deutsch. Akad. Naturforscher, lxvi. (1896) pp. 209-86 (8 pis.). 312 SUMMARY OF CURRENT RESEARCHES RELATING TO cellular spaces of the layers of pith and cortex adjoining the wounded surface. Transpiration of Tropical Plants.* * * § — Herr A. Burgerstein gives the result of observations on the transpiration of plants growing in the hot moist climate of Java when protected both from direct insolation and from rain. He does not confirm the statement of Haberlandt that in these conditions the amount of transpiration is much less than in the temperate climate of Central Europe. (3) Irritability. Periodic Movements of the Leaves of Mimosa in the Dark.f — From a series of observations on the periodic movements of the leaves (chiefly of Mimosa pudica) in the dark, Herr L. Jost comes to the conclusion that they are dependent entirely on changes in temperature ; the effect being tho reverse of that which takes place in the case of flowers. An increase of temperature induces the nocturnal, a decrease of temperature the diurnal position. The phenomena are the same with etiolated as with green leaves. Growth and Curvature of Phycomyces.J — According to M. G. Bullot, the following laws govern the growth and curvature of the sporangio- phores of Phycomyces niiens. At the commencement of the heliotropic or geotropic curvature, there is no accumulation of protoplasm on the concave or decrease on the convex side of the filament ; these take place only at a later period of the curvature. When two mycelial filaments, at any period of their development, come into contact with one another, their growth is at once or very quickly arrested, and the apices of the filaments become gradually more slender. The sporangiophores grow more rapidly in a continuous light than in the dark. (4) Chemical Changes (including Respiration and Fermentation). Formation of Diastase,§ — Prof. W. Pfeffer describes the result of experiments made for the purpose of determining the conditions under which diastase is formed in plants. The subjects were Penicillium glau- . cum , Aspergillus niger , and Bacterium megaterium. An increase in the amount of sugar in the substratum had always the effect of decreasing the production of diastase ; but this result was not produced when the sugar was replaced by another carbohydrate or by glycerin or tartaric acid. The arrest in the production of diastase is not a purely chemical or physical phenomenon ; it is rather a phenomenon of irritation exerted on the organism by a solution of sugar of a certain degree of concentration. Germination of the Almond. || — M. Leclerc du Sablon states that the changes which take place in the germination of the almond conform to those which are characteristic of oily seeds in general. The oil is gradually digested, a certain quantity of fatty acids being at the same time set at liberty. The chief product of the decomposition of the oil is a * Ber. Deutsch. Bot. (resell., xv. (1897) pp. 154-65. t Bot. Zlg., lv. (1897) pp. 17-48 (5 figs.). i Aim. Soc. Beige Microscopie, xxi. (1897) pp. 61-93 (1 pi. and 1 fig.). § Ber. K. Sachs. Ges.'Wiss. Leipzig, 1896 (1897) pp. 513-8. || Iiev. Gen. de Bot. (Bonnier), ix. (1897) pp. 5-16. Cf. this Journal, 1895, p. 551. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 313 non-reducing sugar which may he included among the saccharoses, and which is, in its turn, transformed into a glucose which can be directly assimilated. Fermentation produced by Moulds.* — Herr 0. Emmerling states that by the action of Mucor racemosus on 100 grm. of sugar-cane in a Solution containing 2 grm. potassium phosphate, 1 grm. magnesium sulphate, and 5 grm. potassium nitrate, in 1500 grm. of water, large quantities of C02 are produced, together with about 1 * 46 per cent, of ethylic alcohol. Influence of Temperature and Nutriment on the Respiration of Fungi.f — As the results of a series of experiments on mould-fungi (Sterigmatocystis nigra ), M. G. Gerber has demonstrated that the special CO value of the proportion observed in the case of ripe fruits which aro not acid, and of those which have lost their acidity in the process of ripening (less than unity), is due to the absence of a vegetable acid. The same is the case with acid fruits at a low temperature. The special property of malic acid — that of being consumed at a low temperature in the presence of sugar — is probably the reason why apples ripen at a lower temperature than oranges or grapes. y. General. New Classification of Flowering Plants.^ — M. P. van Tieghem proposes a fresh classification of Phanerogams, dependent on the struc- ture of the seed. The first division is into the Seminate or Perovulate, and the Inseminate. The first of these, comprising the vast majority of flowering plants, furnished with true seeds, is again divided, according as the seed has one or two integuments, into the Bitegminatae and tho Unitegminatee. In the Inseminatae the fruit does not contain any distinct seed which can be separated or which completely detaches itself at maturity. In order to germinate, the fruit must be sown entire. The embryo is formed only at a comparatively late period. These are again divided into 5 groups, the lowest being the Inovulatae already described, which are entirely destitute of true ovules. The remaining 4 groups, the Trans- ovulate, are furnished with transitory ovules. The lowest of these 4 groups is the Jnnucellate ; the other 3 being designated, according to the number of coats of the temporary ovules, the Integminate, Uni- tegminate, and Bitegminate. In the Unitegminate or Icacininee are comprised 10 orders — the Leptaulaceas, Iodaceae, Phytocrenaceas, Sarcostigmataceae, Icacinaceae, Pleurisanthaceie, Emmotaceae, Strombosiaceae, Ximeniaceae, and Tetra- stylidiaceae ; the first 7 comprising the Icacinales in which the carpels are hi-ovulate, the remaining 3 the Ximeniales with uniovulate carpels. The total number of genera is 52. They are all dichlamydeous, with anatropous ovules; the fruit is always a drupe, with endosperm and usually an oily embryo. * Bcr. Deutscli. Chem. Gesell., xxx. (1897) pp. 454-5. See Journ. Chem. Soc., 1897, Abstr., p. 223. t Comptes Rendus, exxiv. (1897) pp. 162-4. + Comptes Rendus, exxiv. (1897) pp. 590-5, 839-44, 871-6, 919-26. Bull. Soc. Bot, France, xliv. (1897) pp. 99-139. Cf. this Journal, ante, p. 216. 314 SUMMARY OF CURRENT RESEARCHES RELATING TO Tlie Bitegminatae comprise at least 315 genera. Of the 7 orders included in it, the Coulaceae, Heisteriaceee, Cathedraceae, Scorodocarpaceae, Ohaunochitaceae, and Erythropolaceae are dicotyledonous, and make up the family Heisterinejs. They are all dichlamydeous ; the pistil is com- posed of syncarpous carpels forming a plurilocular ovary, the carpels are uniovulate, and the fruit is a drupe with fleshy exocarp. The re- maining (monoeotyledonous) order is the Gramineae, forming the family Graminine^j. The author further points out the inaccuracy of the accepted terms for the primary divisions of Phanerogams, the Angiosperms and Gymno- sperms; seeing that in the Epliedraceae, Welwitschieas, Gnetaceae, Araucarieae, and Podocarpeae, all of which are usually included in the Gymnosperms, the seed is as completely enveloped in an ovary as it is in the Angiosperms. He prefers a primary classification into those with and those without a stigma, the Stigmata and the Astigmat^, the latter being identical with the Archegoniatae ; but even this character is not without exception, the Welwitschieae being actually stigmatic and an- archegoniate. Alternation of Generations.* — Eight Hon. Sir E. Fry brings for- ward objections to the theory of an alternation of generations in the higher Cryptogams. He maintains, in the first place, that there is no fixed and impenetrable barrier between the oophore and the sporophore genera- tions, one of them not unfrequcntly passing over into the other. The different generations in the life-history of any given plant are not sepa- rate organisms, but different parts or stages of the same organism. The reproductive energy operates in plants in such a variety of ways as to render it improbable that the facts of reproduction can, with our present knowledge, be reduced to any one scheme, or referred to any single archetype. Plankton-Flora of the Swiss Lakes.j — Dr. C. Schroter gives a com- parative account of the plankton-flora (Bacteria, Cyanopliyceae, Peri- dineae, Diatomaceae, Chlorophyceae, Phanerogamia) of the lakes of Zurich, Constance, Lucerne, and Geneva. The conditions favourable or otherwise for the appearance of these organisms are discussed, and the Variations which some of them exhibit in form and structure in the different lakes, and in others outside the limits of Switzerland. B. CRYPTOGAMIA. Cryptogamia Vascularia. Cheirostrobus a new Type of Fossil Cone.J — Dr. D. H. Scott de- scribes a remarkable fossil from the Calciferous Sandstone near Burnt- island, which he makes the type of a new genus Cheirostrobus , from the palmate division of the sporophyll-lobes, the sporophylls themselves being arranged in crowded whorls. He regards it as most nearly allied to Sphenojphyllum among the Pteridophyta. * Nature, lv. (1897) pp. 422-7. t Neujahrsbl. (1897) v. d. Naturf. Gesell. Zurich (60 pp., 1 pi., and 3 figs.). X Proe. Roy. Soc., ix. (1897) pp. 417-24. Ann. of Bot., xi. (1897) pp. 168-75. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 315 Muscineae. Archegone of Muscineae.* — M. L. A. Gayot regards the archegone of the Muscineae as altogether homologous with the same organ in the Vascular Cryptogams, and gives the following results of observations on its embryogeny. The archegone of the Hepaticae developes not only by intercalary, but also by terminal growth. In the Musci this terminal growth con- tributes greatly to the elongation of the female axis. The canal-cells are not derived from the terminal cell, either in the Hepaticae or in the Mosses. The neck-canal-cells always have the same origin, viz. an initial detached from the mother-cell of the oosphere. The mode of development of the archegone differs in the Anthoceroteae from that in the other families of Muscineae. The archegone of the Sphaerocarpeae has brows of neck-cells, as in the Jungermannieae ; they are sessile, like those of the Riccieae. The pedicel cell is but little developed in the Targionieae, indicating a passage from the Riccieae to the Marchantieae. The archegone of the Targionieae is asymmetrical, like that of the Sphaero- carpeae and of many Marchantieae. In the Marchantieae the number of neck-canal-cells is 8, not 4. In Marchantia it is possible for the ventral canal-cell to be impregnated. In the thallose Jungermannieae the neck of the archegone has as often 6 rows of cells as 5. In the Sphagnaceae the ventral portion of the archegone has not always 4 layers of cells ; the neck has usually only a single layer, except in its lowest portion. The archegone of Anthoceros has 4 canal-cells. In the dioecious Muscineae, the tufts of male and female plants are often at considerable distances from one another, fecundation being effected by animals. Ochrobryum.f — M. E. Bescherelle gives a monograph of this genus of Leucobryaceae, with the following diagnosis : — Theca in pedunculo brevissimo immersa, hemisplierica, cyathiformis ; operculo e basi conica longe subulato, rostrato ; peristomio nullo ; calyptra longissime anguste subulata, basi lacera laciniis breviter fimbriatis. Sixteen species are described, of which seven are new, from Asia, Africa, and America. Gyrothyra, a new Genus of Hepaticae.f — Under this name Mr. M. A. Howe describes a new genus from California, nearly related to Nardia, with the following diagnosis. Stem creeping, foliose, somewhat branched. Leaves succubous ; under-leaves free, bifid ; walls of the leaf -cells with triangular thickenings at the angles, Antherids shortly stalked, in the axils of smaller saccate leaves, forming short median or at first terminal spikes. Involucral leaves in 2-4 pairs. Perianth terminal, confluent for half its length or more with the bases of the involucral leaves, the greater part of the calyptra, and the tissues of the stem, to form a thick-walled perigyne, with a small bulbous or saccate base. Perigyne erect or ascending, making, when mature, nearly a right angle with the stem. Capsule cylindrical, long-exserted, dehiscing spirally by four very long and slender valves; capsule-valves of two * Comptes Rendus, cxxiv. (1897) pp. 781-5. f Journ. de Bot. (Morot), xi. (1897) pp. 138-53 (7 fig3.). X Bull. Torrey Bot. Club, xxiv. (1897) pp. 201-5 (2 pis.). 316 SUMMARY OF CURRENT RESEARCHES RELATING TO layers of cells ; the walls entirely destitute of spiral, semi-annular, or other local thickenings. Elaters free, bi-spiral, acute or bluntly pointed. Spores minutely papillose. Involucel of the sporogone-foot well de- veloped. Exormotheca.* * * § — H. Graf zu Solms-Laubacli has studied in detail the structure of this little-known genus of Hepaticae from Madeira and Teneriffe, in which he includes also Myriorliynchus (Miccici) fimbriatus from Brazil, and corrects the descriptions of previous observers on several points. The systematic position of the genus he considers to be in the Marchantieae, nearest to Lunularia in the structure of the carpoce- phalum. It presents also analogies with the Corsinieae, and especially with Bosclria ; but the elaters are of quite normal structure. Algae. Structure and Multiplication of Pyrenoids in Algae.f— According to observations made by M. W. Chmilewskij, chiefly on Spirogyra, the pyrenoids of Algae multiply exclusively by division. The granules of the starch-envelope are not separated from the pyrenoid by chromato- pliore substance ; the two are in close apposition. The pyrenoid has a stellate form, its arms extending between the granules of the starch- envelope. This was observed also in other Conjugatae, in (Edogoniumr Cladophora , and many Protococcaceae. After division of the nucleus and of the cell has taken place (in Zygnema), each daughter-cell con- tains a single chromatophore and pyrenoid. After about 1^ hours the chromatophore begins to divide centrifugally. The pyrenoid increases somewhat in size, and gradually divides, the nucleus becoming forced into the cavity thus formed in it ; and the starch-envelope divides into two. In a very few instances the division of the pyrenoid preceded that of the cell. The division of the pyrenoid is followed by a longi- tudinal splitting of the protoplasm filaments which radiate from the nucleus. In the zygotes the pyrenoids of the female chromatophores are still to be detected, their starch-envelopes not having entirely dis- appeared. Antherids of Taonia4 — M. C. Sauvageau describes the male organs of Taonia atomaria, which agree, in essential points, with those of Dictyota. The plants which bear antherids are distinguishable, even at a distance, from those which produce tetraspores. New African Genera of Freshwater Algae. §— In a paper on the Freshwater Algae of Africa, chiefly Angola, Messrs. W. and G. S. West describe a large number of new species, together with the following new genera : — Psephotaxus. Thallus subfilamentosus, epiphyticus ; fila brevissima, serie 3-7 cellularum formata, solitaria, subirregularia, et flexuosa, sim- plicia v. pseudoramosa, in muco firmo achroo nidulantia ; cellulae forinarum et magnitudinum variarum, subglobosae, ellipticae, oblongae * Bot. Ztg., Iv. (1897) lte Abt., pp. 1-16 (1 pi.). + 10 pp., 1896 (Russian). See Bot. Centralbl., Ixix. (1897) p- 277. X Journ. de Bot. (Morot), xi. (1897) pp. 86-90 (1 fig.). § Journ. of Bot., xsxv. (1897) pp. 1-7, 33-42, 71-89, 113-22, 172-83, 235-43 (5 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 317 v. subpyriformes, saepe curvatae ; membrana cellularum crassissima et insigne lamellosa ; contentum cellularum granulosum. Incrementum plantarum bipartitioue cellularum intercalari. Under Ulotrichaceae. Temnogametum. Cellulae vegetativae ut in Mougeotia, cylindricae, cbromatophoro elongato complanato, pyrenoidibus uniseriatim dis- positis. Propagatio zygosporis, conjugatione scalariformi lateralive cellularum brevium specialium abstrictarum format's. The type of a new family of Conjugate, Temnogametacea:, characterised by the con- jugation taking place only between cells specially abstricted. Pyxispora. CellulaB vegetativae ut in Zygnema, conjugatione scalari- formi ; zygosporae tubam conjugantem totam inter filamenta complentes ; zygosporas e parte solum contenti cellularum formatae, elliptico-oblongae v. ellipsoid ae, cum porca cingente in planitie diametrorum brevissimorum et rima circumscissa secundum porcam. Under Zygnemaceae. Ichthyocercus, Cellulae cylindrico-fusiformes, subelongatae, ad medium leviter constrictae ; a fronte visae lateribus subparallelis, apicibus basibus- que semicellularum in latitudine subaequalibus (nonnunquam apicibus paullo angustioribus v. paullo latioribus), depressione late minime pro- funda ad apices per latitudinem totam, spina brevi leviter divergente ad angulum unumquemque instructae ; a vertice visae subcirculares. Among Desmidieae, near Teimemorus and Enastrum. Athroocystis. Planlae aquaticae, familias parvas formantes, in strato denso pulverulento aggregatas ; familiis e cellulis numerosissimis com- positis, intra tegmentum tenuissimum firmum non mucosum dense confertis. Propagatio ignota. Placed in Palmellaceae. Conjugation of two Zygotes.* — Herr C. P. Lommen has observed the conjugation with one another of two zygotes in a fertile filament of a Spirogyra sp. Calcareous Algae.f — Miss J. E. Tilden enumerates and describes the algae which live in a calcareous or siliceous matrix found in Min- nesota. One side of a tank was found to be covered by a calcareous incrustation exhibiting various colours, and permeated by three algae (Protophyta) belonging to the Cyanopliyceae, Dicliothrix calcarea , Lyng- bya martensiana calcarea , and L. nana. With them is associated a fungus corresponding to the chlamydospore- filaments of PseudoJielotium granulo- sellum. The other three sides of the tank were covered by a coating of Chaetophora calcarea , together with a Lyngbya, the two appearing to carry on a kind of symbiotic existence. The five algae have apparently, either alone or in combination, the power of causing the precipitation of calcium carbonate from the water. On white sandstone cliffs above the Mississippi river, and imbedded in the rock to the depth of at least half an inch, was found another remarkable alga, ScMzothrix rupicola. Chlorogonium.* — Herr R. H. France describes the structure of this little known genus of Algae. The chromatophores form, in the simplest case, a regular or irregular annular band, which may split into a single or double spiral. The chromatophores of the swarm- cells and those * Arcli. Mikr. Anat., xlix. (1897) p. 462 (1 fig). t Bot. Gazette, xxiii. (1897) pp. 95-104 (3 pis.). i Termeszetrajzi Fuzetek, xx. (1897) pp. 287-308 (1 pi.). See Bot. Centralbl., lxx. (1897) p. 197. 318 SUMMARY OF CURRENT RESEARCHES RELATING TO of the microgametes exhibit no essential difference. The cell-wall is striated, the striation consisting of two intercrossing systems of lines. The cilia are inserted in a tubular sheath. The pulsating vacuoles remain for a time in the zygotes. The author unites with Clilorogonium Dangeard’s genus Cercidium. New Gongrosira.* — Under the name Gongrosira trentepohliopsis, Herr W. Schmidle describes a new species of this genus with two different forms of zoosporange, one of which bears a close resemblance to those of Trentepohlia. Different species of Gongrosira are regarded by algologists as stages of development of species belonging to Vaucheria , Cladophora, and other species of algae. TJroglena.j — Mr. G. T. Moore gives the following amended descrip- tion of the remarkable organism Uroglena americana , which he con- siders (if a plant) to belong to the multicellular Chrysomonadaceae of the class Syngeneticae : — Coenobe irregularly spherical, varying greatly in shape and size, averaging 200-300 p ; no peripheral canals nor in- ternal network of threads; revolving slowly through the water by means of the cilia of individual cells ; individual cells spherical or occasionally slightly elliptical, never produced into an appendage at the end towards the centre of the colony ; two cilia of unequal length, 15-20 p and 2-4 /x respectively, the longer one with decided undulatory motion ; a red spot at the base of the cilia, and a single chromatophore of a yellowish-green colour, usually occupying one side of the cell and clinging close to its wall ; nucleus, non-contractile vacuoles, and numerous oil-globules present. Under certain conditions it is possible for an individual cell to lose its cilia, and to go into a resting stage, often forming a thick gelatinous wall. No mode of sexual reproduction was observed. Coccospheres and Rhabdospheres.J — Mr. G. Murray and Mr. V. H. Blackman record the dredging of these organisms, which they regard as incrusted Algae, from the West Indian seas. In the coccospheres the calcareous scales or coccoliths overlap each other. This arrangement, unlike that of diatoms, admits of the growth of the organism. Each coccolith is attached to the cell by a button-like projection on its inner surface. In the rhabdospheres with projecting rods, the plates do not fit into each other, but their bases are imbedded in the surface of the cell, each by itself without contact. A granular protoplasmic substance was detected within both the coccospheres and the rhabdospheres, but no colouring matter. Eungl. Endophytic Mycorhiza.§ — M. J. M. Janse has examined the roots of 75 species of plants (including Gymnosperms, Pteridophyta, and one liverwort) in the forests of tropical Java, and finds 69 of them in- fested with an endophytic mycorhiza, the arborescent species examined affording no exception. The filaments offer a close resemblance in all cases; and the author discusses the resemblances and differences between * Oesterr. Bot. Zeitsclir., xlvii. (1897) pp. 41-4 (1 fig.), f Bot. Gazette, xxiii. (1897) pp. 105-12 (1 pi.), j Nature, lv. (1897) pp. 510-11 (8 figs.). § Ann. Jard. Bot. Buitenzorg, xiv. (1896) pp. 53-201 (10 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 319 the structure of these and that of Bacillus caucasicus, ffliizobium, Frankia , and Clostridium Pasteurianum. With the exception of the tubercles of Lycopodium cernuum, the fila- ments of the parasite always enter the tissue by perforating the external wall of an epidermal cell. The roots thus attacked are usually, though not always, destitute of root-hairs. It is most commonly the younger parts of the roots that are attacked, but the position of the tissue chiefly infected differs in different cases. The intercellular spaces may also be attacked, or may be left free. The attacking kyphse are in some cases characterised by the formation of “ vesicles,” apical swellings which appear to assist in their penetration of the tissues. Within the cells of the internal layers of the infected tissues, they also form bodies which the author terms “ sporangioles,” globular structures varying in diameter from 2 • 5 to 23 /*,, filled at first with a hyaline substance which subse- quently becomes granular, and is composed of spherical corpuscles, which he designates “ spherules,” varying between 1 * 5 and 6 p in diameter. The author regards the connection of parasite and host as one of true symbiosis, the parasite furnishing to the host nitrogenous food-materials, which it obtains by assimilating the free nitrogen of the atmosphere, while it receives protection in return, as well as food-material in the form of carbohydrates. It is in fact a facultative aerobe, which pene- trates living tissues for the purpose of avoiding oxygen. Laboulbeniaeese.* — Mr. B. Thaxter publishes a monograph of this remarkable family of Fungi, belonging to the Ascomycetes, but display- ing singular affinities with the Floridem. They are all parasitic on living insects, mostly aquatic, and are for the most part American. Of the 28 genera only 9 have at present been found in the Old World. The genera are arranged in two groups — the Endogenee, in which the antherozoids are formed endogenously in antherids, 26 genera ; and the Exogenas, in which the antherozoids are formed exogenously, 2 genera. The Endogense are again divided into the Peyritschielleae, 11 genera, with compound antherids, and the Laboulbenieae, 15 genera, with simple an- therids. Each of these orders includes monoecious and dioecious genera. The main body of the fungus is usually quite simple in structure, composed of several cells, and is attached by a disc-like base to the chitinous integuments of the insect ; there is no mycele in the body of the host. Towards the summit of the filament are filamentous appen- dages which bear the antherids ; lower down is the procarp, a multicel- lular structure containing a carpogenic cell, and bearing a trichogyne. After fertilisation the carpogenic cell divides several times, and develops the asci ; while these are being differentiated, the sterile cells of the procarp form the wall of the perithece. The perithece is usually a flask- shaped body, opening by a pore at the apex, and resembling in many respects the cystocarp of the Florideac. The ascospores are usually dis- charged in pairs from the perithece. The antherozoids (pollinoids) are very minute, and are often rod-shaped ; they attach themselves in large numbers to the trichogyne, but the actual fusion has not been observed. The trichogyne may be simple or much branched, and may consist of a * Mem. Amer. Acad. Arts and Sci., xii. (1896) pp. 187-429 (2G pis.). See Bot. ■Gazette, xxiii. (1897) p. 216. Cf. this Journal, 1896, p. 218. 320 SUMMARY OF CURRENT RESEARCHES RELATING TO single cell, or may be a compound multicellular structure. It is never attached directly to the carpogenic cell ; the fertilising process must be carried through one or through several cells before it reaches the carpo- genic cell. The cells of the trichogyne communicate with one another through strands of protoplasm ; and the author believes that the nucleus of the antherozoid must pass the length of the trichogyne from cell to cell before finally fusing with the female nucleus of the carpogenic cell. New Genera of Fungi.* * * § — M. N. Patouillard describes, under the name Gyclostomella , a new genus of Hemi-hysteriaccae from Costa Rica, with the following diagnosis : — Stromata foliicola, orbicularia, dimidiato- scutata, centro adfixa ; peritliecia radiantia, in stromate circulariter dis- posita, ostiolis hvsterioideis donata ; sporidia ovata, simplicia, brunnea ; mycelium superficial nullum. Cryptophallus g. n. is separated from Ithyphallus by Mr. C. H. Peck,! on the ground of the volva rupturing in a somewhat circumscissile manner, the upper part of it being carried up and remaining on the pileus, persistently concealing the stratum of spores. It consists of a new American species, C. albiceps. Mr. J. D. Ellis and Mr. F. D. Kelsey J separate from JEcidium a new genus JEcidiella , distinguished by its uniseptate spores. Several species are described. From Java, M. E. de Wildeman§ has obtained a new genus of Mucorini, which he names Massartia, with the following diagnosis : — Mycele ramifying in the substratum fthe mucus of terrestrial Algae) ; zygospores produced in a ball of interwoven filaments, which are thicker than the other portions of the mycele, globular, formed by the fusion of the apices of two mycelial branches; membrane which separates the zygospore from the mycelial filaments often thickened ; zygospores smooth, with a comparatively thick wall. Sporanges unknown. Endophytic in the roots of a Celtis in the forests of Java, M. J. M. Janse || finds a fungus, which he regards as the type of a new genus of Elaphomycetacem, and names Celtidia duplicispora. The genus differs from others of the order in its (probably) parasitic habit, and in its sep- tated spores, which do not occur in any other member of the Tuberaceae. Tubeuf’s Parasitic Diseases of Plants.^ — An English edition has now appeared of this standard work on the Gryptogamic diseases of Plants. The 1st part is divided into 9 chapters, viz. : — The Parasitic Fungi ; Reaction of Host to parasitic attack ; Relation of Parasite to substratum ; Natural and artificial infection ; Disposition of Plants to disease ; Preventive and combative measures ; Economic importance of diseases in plants ; Symbiosis : Mutualism ; and Symbiosis : Nutricism. The 2nd part is devoted to a Systematic Arrangement of the Cryptogamic * Bull. Herb. Boiss., iv. (1896) pp. 655-6. t Bull. Torrey Bot. Club, xxiv. (1897) p. 147. X Tom. cit., p. 208. § Ann. Soc. Beige Microscopie, xxi. (1897) pp. 25-7 (1 pi.). || Ann. Jard. Bot. Buitenzorg, xiv. (1896) pp. 202-6 (1 pi.). ‘ Diseases of Plants induced by Cryptogamic Parasites/ by Dr. Karl Freiherr v. Tubeuf; English edition by W. G. Smith. London, 1897, xvi. and 598 pp. and 330 figs. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 321 Parasites ; all the known species being fully described the higher and lower Fungi ; the Pathogenic Slime-Fungi (Myxomycetes) ; the Patho- genic Bacteria; the Pathogenic Algae. The book is admirably illus- trated ; and there is a copious index. It may be regarded as a complete monograph of the Fungi and other cryptogamic parasites which are pathogenic to plants. Rusts of Corn.* — Herr J. Ericksson sums up the present state of our knowledge respecting the species of Puccinia parasitic on corn-crops. There are now known 10 forms belonging to 5 r&puted species, viz. : (1) P. graminis, one form on rye and barley, another on oat, and a third on wheat ; (2) P. dispersa, one form on rye and another on wheat ; (3) P. glumarum , one form on rye, another on. wheat, and a third on barley ; (4) P. simplex, on barley ; (5) P. coronata, on oat. Of these 10 forms it is only those of P. graminis on rye and barley which occur also on other kinds of grass, viz. both of them on Triticum repens, T. caninum , Elymus arenarius, Bromus secalinus, Hordeum jubatum, &c. ; the latter also on JDadylis glomerata, Alopecurus pratensis, Milium effusum, Arena elatior, A. sterilis, &c. He confirms observations already made as to the my coplasm- condition assumed by certain parasitic fungi. New Conidial Form of Chgetomium.f— On a Brazilian bark, M. E. Boulanger finds a hitherto undescribed fungus, which he names Dicyma ampullifera . Under certain conditions of culture, this fungus can be re- duced to an atrophied Sporotrichum form, while its most perfect form is a Chsetomium , which will develop only on banana-leaves or on wood. The perithece produced in this form is that of a Pyrenomycete belonging to the family of Sphaeriacese. The author names it Chsetomium Zopfii , Dicyma ampullifera being its conidial form. Venturia and Fusisporium.t — Dr. R. Aderhold gives a resume of the species of this family of Pyrenomycetes, the perithecial forms of which are known as Venturia , and establishes the connection with the respective conidial forms which comprise the genus Fusicladium. Several new species are described, including V. Tremulse, of which both forms are found on the leaves of the aspen, and F. Fraxini, both forms of which occur on leaves of the ash. Mycele of AScidium Magellanicum.§ — Herr P. Magnus has traced the growth of the mycele of this fungus in the wood, cortex, and pith of the “ witch-broom ” of the barberry, as well as that of the haustoria, and confirms previous statements as to the intercellular growth of the hyphse. It was not found in the cambium. Relation of Yeasts to Malignant Tumours.il— Dr. A. R. Defendorf, after reviewing the literature of cancer-bodies, most of which have been noticed in this Journal, considers that it is justifiable to draw certain conclusions as to the relationship of fungi to malignant tumours in man. The first is that the parasitic Protozoa described by numerous investi- * Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 183-94. Cf. this Journal, ante, p. 61. f Eev. Gen. de Bot. (Bonnier), ix. (1897) pp. 17-26 (3 pis.). Cf. this Journal, 1895, p. 557. X Hedwigia, xxxvi. (1897) pp. 67-83 (1 pi.). Cf. this Journal, ante, p. 152. ■§ Ber. Deutsch. Bot. Gesell., xv. (18£7) pp. 148-52 (1 pi ). || Trans. Amor. Micr. Soc., xviii. (1897) pp, 219-45. 322 SUMMARY OF CURRENT RESEARCHES RELATING TO gators during tlie past eight years are probably yeast-fungi. The second is that yeast-fungi have been found in man and in lower animals affected with malignant tumours. These, when isolated, grown on nutrient media, and, when inoculated into other animals, gave rise to malignant tumours which showed the same characteristics as the original tumours. Origin of Lichens.* * * § — Mr. F. Clements criticises very unfavourably Reiuke’s view that Lichens must be regarded as a distinct class of Cryptogams, independent of the Fungi. They may, he considers, be traced back in all cases to distinct Fungus-ancestors. The Ascolichenes, to which the great majority belong, were derived from the Ascomycetes at an earlier period than the Hymen olichenes from the Hymenomycetes. Their great specialisation and the interval of time that has elapsed, have, however, to a considerable extent, obscured the points of de- parture. Pertusariese.f — Herr 0. Y. Darbishire gives a monograph of the German species of this family of lichens, 31 in number, belonging to 7 genera, viz. : — Pertusaria, Pionospora, Ochrolechict, Vciriolarici, Mega- lospora, Varicellaria, and Phlyctis. He then enters into a full descrip- tion of various points in their anatomical structure, especially the formation of the soredes and of the apotheces. In Variolaria and Oclirolechia , and probably also in all the other genera, the sorales, or clusters of soredes, appear to be metamorphosed apotheces. Structure of Agaricus (Pleurotus) ostreatus.J — M. L. Matruchot has followed out the development of this fungus in various media, with the following results : — There are three different modes of fructification : — by budding carpophores ; the cauliflower fructification ; and the coralloid fructification. The cystids appear to be deformed basids. The normal basids, the hymenial cystids with 1, 2, or 3 sterigmas, the extra-hymenial cystids or pseudo-conids, and probably also the normal conids, must be regarded as differentiations from a single elementary type. Calostoma.§— Mr. C. E. Burnap gives a review of the American species of this genus of Gasteromycetes, and sums up in favour of its affinity with Tulostoma rather than with Geastei\ In both Calostoma and Tulostoma the spores are borne laterally on the basids, which is not the case with Geaster , nor w ith any other genus of Gasteromycetes. Presence of an Oidium in Pseudo-lupus vulgaris.il — Mr. T. C. Gilchrist and Mr. W. R. Stokes report the discovery of an oidium in the diseased tissue taken from a case of pseudo-lupus of eleven years duration. Sections showed hypertrophy of the epidermis, abscesses, and, in the deeper parts of the corium, tuberculoid nodules. In the abscesses round and oval cells 10-20 /x in diameter were observed. Many of these cells showed buds, a doubly contoured membrane, and occasionally vacuoles. Very few giant cells were noticed. From the pus was cultivated, on glycerin-agar and on potato, an oidium, having at * Amer. Naturalist, xxxi. (1897) pp. 277-84. Cf. this Journal, 1895, p. 82. t Engler’s Bot. Jahrb., xxii. (1897) pp. 593-671 (39 figs.). X Rev. Gen. de Bot, (Bonnier), ix. (1897) pp. 81-102 (1 pi. and 19 figs.). § Bot. Gazette, xxiii. (1897) pp. 180-92 (1 pi.). || Bull. Johns Honkins Hosp., vii. No. 64. See Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 692-4! ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 323 times a short mycele. The colonies were at first grey, afterwards be- coming white and granular. Another characteristic feature was the formation of a membrane which gradually spread over the surface of the medium. Experiments made on animals with the affected skin were negative, but injections resulted in the formation of growths in the abdominal cavity, lungs, and bronchial glands. Pure cultures were obtained from the deposits. Association of Chsetophoma oleacina and Bacillus Olese.* — Under the name of Chsetophoma oleacina , M. P. Vuillemin had described a hyphomycete usually found in company with Bacillus Olese ; the two appearing to play a similar part in causing the disease of olive trees to that played by Mycogone rosea and Tricholoma terreum — that is to say, the fungus paves the way for the bacteria into the host-plant. Recently the author has verified the existence of Ch. oleacina and of B. olese in cankered ash trees of France and Germany. This is another example of the commensalism of a schizomycete and a hyphomycetous fungus on trees. Fossil Fungi. j— From the evidence drawn from the remains of Fungi found in the different geological formations, Herr M. Staub supports the view that the aerial forms have sprung from marine ancestral types belonging to the Phycomycetes. The oldest known fungus, Palseoachlya penetrans , was a parasite on coral in the Silurian period. Other Phyco- mycetes were abundant in the Carboniferous period ; and remains of Discomycetes also occur. A Bhizomorpha , an JEcidium , and members of various families of Ascomycetes, are found in the Chalk. The fungi of the Csenozoic period present a very close resemblance to those which exist at the present time. Myxomycetes. Vilmorinella, a new Genus of Myxomycetes.f — Parasitic on the mucus of several species of Micrococcus on gangrenous potatoes, M. E. Eoze finds an organism which he regards as the type of another new genus of Myxomycetes characterised by its extreme simplicity. It consists of a naked spherical rudimentary plasmode, which, under certain conditions, becomes encysted. Myxobotrys.§ — Recurring to his account of this genus, Herr H. Zukal admits its identity with Cliondromyces. He maintains, however, in opposition to Thaxter, || that the genus belongs to the Myxomycetes, and not to the Schizomycetes. Protophyta. a. Schizopliycese. Rhizosolenia4 — Under the name Bhizosolenia Peragalloi , Count Abbe F. Castracane describes a new species of this genus from the * Bull. Soc. Mycol. de France, xiii. (1897) pp. 44-5. See Centralbl. Bakt. u. Par., 2te Abt., iii. (1897) p. 256. f SB. K. Ung. Naturw. Gesell. Budapest, Feb. 12, 1897. See Bot. Centralbl., Ixix. (1897) p.267. X Comptes Kendus, cxxiv. (1897) pp. 417-8. § Ber. Deutscb. Bot. Gesell., xv. (1897) pp. 17-8. Cf. this Journal, ante, p. 151. II Cf. this Journal, 1893, p. 370. Atti Accad. Pont. Nuovi Lincei, 1. (1897) pp. 53-8. 324 SUMMARY OF CURRENT RESEARCHES RELATING TO Atlantic, characterised by having four terminal setae ; and points out that West’s monotypic genus Attheya has been erroneously regarded as nearly allied to Bhizosolenia, whereas, in reality, the former genus belongs to the Eaphideae, the latter to the Cryptoraphideae. Movements of Oscillatoriacese. — Herr K. Kolkwitz * describes in detail the nature of the oscillating movements in several species of Spirulina and Oscillatoria. These are of two kinds, a movement of nutation and a movement of rotation ; the two movements may be ex- hibited in the same filament, one end of which may rotate, while the other nutates. Herr C. Correns f offers a somewhat different explanation, from observations made chiefly on Oscillatoria princeps . The outer wall of the cells exhibits a distinctly reticulate structure. The outer layers have a marked positive tension. No movement could be detected in the cytoplasm. The direction of the torsion may be to the right or to the left, but is constant in the same species. The funnel-formation at the end of creeping filaments is due to a curvature (often very slight) of the extremity, combined with the resistance of the water. The author never observed any movement of nutation. The filaments move only when closely attached (not merely iii contact) to a solid substance. External granules remain but slightly attached to the filament, and may move along it, the movement being quite as rapid along isolated dead cells. The author concludes that the filaments excrete a colourless jelly, which surrounds them in the form of a very soft sheath. They never swim freely in the water, the sheath taking no part in the move- ment. The filament may consist of active and inactive zones. The movements cannot, he considers, be attributed either to cilia, to a peri- pheral layer of pi-otoplasm, or to the expulsion of water. B. Schizomycetes. Behaviour of Bacteria to Chemical Reagents.f — Herren Th. Paul and B. Kronig made experiments for the purpose of testing the effects of various acids, bases, oxidising agents, and metallic salts, on bacteria, the bacteria employed being Staphylococcus pyogenes aureus and the spores of Bacillus anthracis. The salts of mercury, gold, and silver were found to exert a specific poisonous effect, while those of platinum had little, if any action. The disinfecting action of metallic salt solutions, in which the metal is present as a complexion, is very small. The effect of mer- curic chloride is greatly decreased by the addition of sodium and other chlorides, but is not affected by other salts, such as sodium nitrate. The acids only act as disinfectants in concentrations of the gram molecular weight per litre, and exhibit a specific action which is not proportional to the concentration of the hydrogen ions. The weak organic acids appear to act according to the degree of dissociation. The action of the hydroxides of lithium, sodium, and potassium is about equal, and that of ammonium very slight. Of the ordinary agents, nitric acid, chromic acid, chloric acid, and permanganic acid, act in the order stated. The halogens have * Ber. Deutsch. Bot. Gesell., xiv. (189G) pp. 422-31 (1 pi.). + Op. cit., xv. (1897) pp. 139-48. % Zeit. Physikal. Cliem., xxi. (1896) pp. 414-50. See Jouru. Chem. Soc., 1897, Abstr. p. 155. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 325 also a specific action, which is most powerful in the case of chlorine. Phenol acts better in 5 per cent, solution than at higher concentrations, and the effect is increased by the addition of metallic salts, especially sodium chloride ; it is diminished if mixed with alcohol, and is never as great as that of mercuric chloride. Plurality of Morbific Products from a single Pathogenic Microbe.* — M. A. Charrin contends for the plurality of morbific products from a single pathogenic microbe, asserting that the present notion which assigns the power of a micro-organism over the animal body to a single product, a toxin, is insufficient to explain the phenomena. The contention is supported from experiments made with cultures of B. pyocyaneus. The substances precipitated by alcohol induce emaciation, enteritis, and fever, and also act as excito-motors of the spinal cord. The substances which are soluble in alcohol principally affect the heart ; while the volatile aromatic principles act as constrictors on the capillaries. Besides the foregoing, there is some evidence of the presence of a ferment which is capable of decomposing asparagin. The fact that the B. pyocyanens consumes much oxygen which is necessarily drawn from our tissues, and that it elaborates ammoniacal compounds and traces of methylamin, points in the same direction. The part played by the blue or green pigment, though inconsiderable, cannot be overlooked. From the foregoing considerations, and while admitting that there is a principal toxin, usually albuminoid, more important than the rest, it is none the less true that other morbific agents are called into existence by a single microbe. Such data afford an easy explanation of the multiplicity, the variety, and the occasional predominance of certain symptoms. Microbic Agents of Cheese-Ripening.f — Experiments made by M. E. de Freudenreich relative to the maturation of cheese tend to show that the lactic ferments are endowed with the power of attacking casein and of transforming it into soluble albuminoid substances and amides. Taking into consideration the enormous increase in the number of lactic ferments in cheese during the process of maturation, it becomes evident that this variety of bacteria plays the most important part in the ripen- ing of cheese, at any rate of hard cheese. In soft cheese, Oidium lactis and yeasts are equally active. It is further pointed out that in ripening cheese the lactic acid ferments are quite different from those in sponta- neously coagulated milk ; hence it would seem possible that there exists a special class of ferments which, in virtue of their less intense lactic acid formation, are specially adapted for decomposing casein. Bacteria and the Decomposition of Rocks, f — Mr. J. C. Branner dis- cusses the question whether bacteria are important agents of rock decay, a notion promulgated by Muntz in 1890. This writer stated that the nitrifying organism was always present in decomposed rocks ; and this view was generally accepted. From a review of numerous observations made by competent persons, the author is of opinion that it is quite improbable that bacteria are responsible for any considerable part of the * Comptes Rendus, cxxiv. (1897) pp. 1047-9. t Ann. de Micrographie, ix. (1897) pp. 185-93; and Centralbl. Bakt. u. Par., 2te Abt., iii. (1897) pp. 23L-5. Cf. this Journal, 1896, p. 224. X Amer. Journ. Sci., iii. (1897) pp. 438-42. 1897 z 326 SUMMARY OF CURRENT RESEARCHES RELATING TO decay. For, in tlie first place, it is now known that nitrifying bacteria do not penetrate the soil to a depth of more than three or four feet, and, secondly, that granite rocks are often decomposed to depths of more than 100 feet. Bacteria in Ice.* * * § — A bacteriological examination of ice sold in Padua, made by Dr. G. Catterina for the purpose of testing its purity, showed that there were about 10,000 bacteria per ccm. of the ice water. Numerous non-pathogenic water bacteria were isolated, and one organism with the biological and morphological characters of B. coli commune. In addition to the Schizomycetes, Algae, Protozoa, Vermes, and larvae of certain dipterous insects were also observed. Bacteriaceae of Bogheads.f — According to M. B. Eenault, Boghead coal contains large numbers of micrococci, often difficult to distin- guish owing to their smallness and the slight difference between their colour and that of the surrounding substance. The cocci are found scattered about irregularly in the broken down and disorganised thalli, or arranged along the course of the median membranes, the invasion having proceeded step by step from the periphery to the centre. To the different micrococci of Bogheads the name M. pelrolei is given, the varieties being distinguished by the letters A to F. The description of the species is Spherical cells measuring from 0*4-0 *5 /x, the walls being visible under magnification of 1000-1200 diameters; colourless or only faintly coloured, often resembling bright highly refracting spherules imbedded in the surrounding medium, or, at a different focus, as hemi- spherical cavities of the same diameter. Evolution of Mucus in Cancer Ceils. Prof. Quenu and M.Landel draw the following interesting and novel conclusions relative to the for- mation of pathological mucus, from a histological investigation of a u colloid” cancer of the rectum. Two epitheliums of different form and origin may co-operate to form a single tumour by the simultaneous pro- duction of similar elements. The presence of mucus in cancerous elements is not to be regarded as indicative of degeneration, but as a normal function of these elements, not lessening their vitality in the least. In cancer cells derived from squamous epithelium, the formation of mucus is due, not to an alteration or secretion of cytoplasm, but to a transformation of the chromatic elements of the nucleus into a substance having the characters of mucus. The authors point out that Lukjanow had observed precisely the same kind of transformation under normal conditions, viz. in the goblet-cells of the intestine of the salamander. Plague Bacillus. — Dr. E. Abel § records the results of an exhaustive investigation into morphological and cultural characters of the jfiague bacillus. In size the bacillus varies from 1 to 4 or 5 /x in length, and is about 1 /x broad. In old cultures involution forms are frequent. It is quite motionless, and is easily stained with the usual anilin dyes, but not by Gram’s method. Neither capsule nor spore formation was observed. Cultures were successful in the ordinary fluid and solid media ; the best * Aiti Soc. Veneto-Tventina, Padua, iii. (1897) pp. 221-9. t Comptes Kendus, cxxiv. (1897) pp. 1315-8. X Ann. de Micrograpliie, ix. (1897) pp. 145-65 (3 pis. and 35 figs.). § Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 497-517. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 327 being a 2 per cent, pepton solution, with 1 or 2 per cent, of gelatin. The optimum temperature was 37°, and growth took place under aerobic and anaerobic conditions. Cultures were fatal to mice and guinea pigs, but not to pigeons, the animals dying from pyogenic septicaemia. Experi- ments as to the resistance of the plague bacillus showed that the best method for disinfecting was moist heat at 100°, i. e. steam. According to Ur. W. M. Haffkine,* the plague bacillus is easily recognised by a stalactite growth in broth. The broth, richly inoculated with the bacillus, must be kept in an absolutely quiet position, as the slightest jar destroys the reaction. In from 21-48 hours flakes appear underneath the surface, forming little islands of growth ; from these long stalactites grow downwards, the liquid always remaining clear. If after 5 or 6 days the flask be shaken, the whole growth falls to the bottom, the islands retaining their form, while the stalactites are perfectly dis- integrated. The bacillus is also recognisable by involution forms on agar. The medium must not contain glycerin, must not be freshly pre- pared, the surface must be perfectly dry, and the reaction alkaline. The surface must be inoculated abundantly. In usually from 3 to 4 days the individual microbes swell up, forming large round, oval, or pear- shaped bodies, which eventually are quite unstainable. The bacilli become unrecognisable, acquiring the appearance of a yeast cell or an alga. The swelling may continue until the body is twenty tirms larger than the original bacillus. Similar forms are demonstrable in the tissues of animals dead of the disease, and then they resemble modified blood- corpuscles, or disintegrated tissue-cells, or stained drops of albumen. Epidemic of Botulism.f — By means of a bacteriological examination of fragments of sausages suspected of causing an outbreak of botulism among troops in a Belgian artillery barrack, Dr. Dineur isolated three varieties of coli bacillus, one of which (variety A) was also isolated from the body of a mouse fed on the same sausages. By continued cultivation the virulence of this variety A was reduced and even abolished. The source of the bacteria was probably the flesh of an infirm or diseased animal, from which the sausages Were made. Bacteria normal to Digestive Organs of Hemiptera4 — Prof. S. A. Forbes gives a preliminary account of the caecal appendages of certain Hemiptera, which were found to be invariably loaded with myriads of bacteria, differing in genus and species in the different insects, but always confined to these organs. The bacteria were cocci and bacilli ; they responded to the ordinary stains, and were cultivated in fluid and on solid media. Variation of Bacteria from Age.§ — Dr. H. G. Dyar replanted the “ new species ” of bacteria described by him after intervals varying from one to two years, for the purpose of ascertaining if there had arisen any differences of form and function. The conclusions arrived at from these replantings are : — (1) species under long cultivation tend to be con- stant in their characters ; (2) some species lose in vigour; (3) some gain * Brit. Med. Journ., 1897, i. p. 1461. t Bull. Soc. Beige de Microscopie. xxiii. (1896-7) pp. 47-66. X Bull. Illinois State Lab., iv. (1895) pp. 1-7. § Trans. New York Acad. Sci., xv. (1895-96) pp. 148-53. z 2 328 SUMMARY OF CURRENT RESEARCHES RELATING TO in vigour, exhibiting certain characters more strongly, or even acquiring new characters. Cultures of 9 species died ; of 6 became less vigorous ; of 14 were constant ; while 9 became more vigorous, with more positive or new characters. Bacillus capsulatus aerogenes.* * * § — Prof. E. K. Dunham records five fatal cases of infection with B. capsulatus aerogenes, the special symp- toms of which are mortification attended with blackening of the affected parts, considerable emphysema from decomposition gas, and the absence of pus. The bacillus is a large straight rod about 0 • 9 /x in diameter, with rounded ends. It is easily stained. In the subcutaneous fluid of animals it possesses a capsule, but not on artificial media. It is a motion- less anaerobe which produces gas (about two-thirds H and one-third C02). On blood-serum it forms spores, which cause a central bulging of the rodlet. It coagulates milk in 24 hours, producing gas and souring the milk. It grows well in bouillon to which 1 per cent, of glucose is added. Experiments on animals with pure cultures gave positive results, the animals dying within 24 hours, with development of much gas in the tissues and organs. Action of Currents of High Frequency on the Virulence of Strepto- cocci. | — M. L. Dubois shows that electrisation of cultures of Streptococcus reduces the vitality and virulence of this microbe. The apparatus used for electrising the serum cultures was that employed by d’Arsonval and Charrin. After eight daily exposures of 20 minutes, the effect of inocu- lating 2 ccm. of culture was practically nil. The effect produced was due to attenuation of the toxin, and not to the formation of antitoxin. Thermophilous Cladothrix.J — Herr Kedzior describes a species of Cladothrix which grows between the limits of 35° and 65°, the optimum temperature being 55°. It forms spores which are very resistant to heat, insolation, desiccation, and disinfectants. The original source was sewage water. Cultivated in equal bulks of the water and bouillon . at 55°, it turned the medium turbid, and in 16 hours formed flakes from which the thermophilous bacteria could be isolated by plate cultures. Bacteria of Conjunctivitis. — According to Dr. Th. Axenfeld,§ con- junctivitis is commonly of three kinds, viz. the acute, caused by the Koch-Weeks bacillus, the gonorrhoeal, and the chronic, produced by a diplobacillus. The latter organism, with which the author is principally concerned, is about 2 /x long by 1 /x broad, usually occurs in pairs, has much resemblance to the bacillus of Friedlaender, and is easily stained, though decolorised by Gram’s method. It grows best at incubation temperature in media having a distinctly alkaline reaction and containing some human body-juice, such as ascitic, hydrocele, or ovarian fluid. It is essentially aerobic, is devoid of movement, does not form spores, and liquefies the medium, though slowly. Experiments made on the human subject gave positive results, the incubation period being four days. * Bull. Johns Hopkins Hosp., viii. (1897) pp. 68-74. t Comptes Rendus, cxxiv. (1897) pp. 788-90. X Arch. f. Hygiene, xxvii. No. 4. See Centralbl. Bakt. u. Par., 2,s Abb, iii. (1897) p. 154. § Centralbl. Bakt. u. Par., lt0 Abb, xxi. (1897) pp. 1-9 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 329 Dr. S. Stephenson * confirms the observations of Weeks, Moran, and Beach relative to contagious ophthalmia. In all such cases a bacillus 75 fx-1 /i long is demonstrable, the numbers of the organism present being directly proportional to the severity of the case. This bacillus is found in and upon the cells of the discharge, and also free in the liquor. It is easily stained with alkaline methylen-blue, but is decolorised by Gram’s method. The most suitable cultivation medium was found to be Kanthack and Stephens’ serum-agar. Actinomycetic Form of the Tubercle Bacillus.f — According to MM. Y. Babes and C. Levaditi, the bacillus of tubercle should be definitely placed in the same group as Actinomyces. This view is based on obser- vations made on the brains of rabbits which had been infected by sub- virulent cultures of human tubercle. In these, clumps of bacilli were found to have undergone a peculiar modification. The centre of the clumps, when stained by the Ehrlich method, showed a network of fila- ments resembling in general appearance a mycele of tubercle bacilli. The central mycele is surrounded by a zone of clubs, not infrequently connected with the ends of the mycele. The clubs do not stain by the Ehrlich method, and are about the same size as those of Actinomyces. The clubs are resistant to the action of acids and alkalies, and can be stained by the methods adopted for demonstrating the clubs of Actino- myces. Serum Diagnosis with Agglutination Reaction in Typhoid Fever, f— The agglutination reaction, say Prof. F. Widal and M. A. Sicard, is nothing else than a reaction of the infection period, and is usually mani- fested during the first days of the malady ; and, though sometimes delayed, is but rarely wanting. Moreover the agglutination phenomenon is not a vital reaction, at least as far as the microbes are concerned. When a negative result is obtained from the examination of a suspected case, the probability is against typhoid ; but the examination should be repeated on several consecutive days. The probability against typhoid increases directly with the duration of the disease ; that is to say, a nega- tive result at a late period is final. On the other hand, a positive result should be considered as a certain sign of typhoid. Presence of the Agglutinative Property in the Blood-Plasma and other Body-Juices. § — MM. Ch. Achard and R. Bensaude made experi- ments which tend to show that the agglutinative property of blood-plasma does not reside in the leucocytes. The blood used was rendered incoagulable by means of leech extract/and then filtered through cotton- wool. The cotton-wool was washed with normal serum, and the fluid thus obtained was found to contain 3000 white to 6000 red corpuscles per cubic millimetre. This fluid, so rich in leucocytes, was not found to possess a stronger agglutinative action than the serum devoid of white corpuscles. Aetiology of Rabies. 1 1 — Dr. G. Memmo isolated from the cerebro- spinal fluid, from the parotid, and from saliva of man and animals, * Lancet, 1897, i. pp. 1531-3. ; f Comptes Rendus, exxiv. (1897) pp. 791-3. X Ann. Inst. Pasteur, xi. (1897) pp. 353-432. § Comptes Rendus, cxxiii. (1896) pp. 503-5. |] Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 657-64 (1 pi.). 830 SUMMARY OF CURRENT RESEARCHES RELATING TO a Blastomycete which is cultivable in bouillon containing glucose and tartaric acid, and also on solid media with an acid reaction. The acidity of the culture medium is an interesting feature, inasmuch as the reaction of central nervous tissue is acid. Injection of pure cultures into animals (guinea-pigs, dogs, rabbits) proved fatal after a lengthy incubation period. The symptoms of the disease resembled those of rabies, the most prominent phenomenon being paralysis. Cattle Malaria.* — Herren A. Celli and F. S. Santorini describe a disease affecting cattle in the Roman Campagna, which is characterised by fever, anaemia, occasionally by haemoglobinuria, and always by the presence of endoglobular parasites in the blood. This disease is apparently identical with Texas fever (Smith, Kilborne), haemoglobi- nuria (Babes), and hematinuria (Sanfelice). The parasite appears under two forms, one exhibiting merely local movements within the red corpuscles, the other manifesting amoeboid movements. The former is from 1—1*5 /x in size, and the latter two or three times as large. The amoeboid form often exactly resembles the Pyrosoma bigeminum (Smith). The exact relationship between the two forms and the reproduction stages were not clearly made out. Classification of Malaria Parasites.f — Dr. X. Lewkowicz divides the htemosporidia of malaria into two groups. In Group I. the develop- mental stage of the sporidia lasts for 2 to 3 days ; development is endo- globular, and the adult form spheroidal. The species of this group are H. tertianee , having a developmental period of 2 days, and H. quartcinse, with one of 3 days. In Group II. the developmental period is more than 3 days, and development is extraglobular, the adult being crescent-shaped. Four species of this group are enumerated : — H. undecimanse , with a develop- mental period of 10 days ; H. sedecimanse , of 15 days ; H. vegesimo- tertianse, of 22 days ; and H. (?), with an undetermined period of sporidia develo|)inent, the adult form of this variety being cigar-shaped. Microbes of Yellow Fever. — Prof. G. Sanarelli + has isolated from the blood of persons affected with yellow fever a bacillus varying in size from 2-4 /x, and as a rule twice or thrice longer than broad. Its ends are rounded, it is very pleomorphous, and is mostly found in little groups in the capillaries of the kidney, liver, &c. The best way to demonstrate it is to begin by incubating a piece of fresh liver at 37° C. for 12 hours. The bacillus grows well on gelatin, which is not lique- fied. Agar cultures afford an important means of diagnosis; for when incubated at 37°, the colonies are roundish, grey, smooth, and transparent ; but if grown at 20°-22°, the colonies are like drops of milk, opaque, prominent, and with pearly reflections. The bacillus is a facultative anaerobe, stains well, ferments sugar, but does not coagulate milk ; it strongly resists drying, dies in water at 60°, but lives for a long time in sea water, and is killed in 7 hours by sun-rays. It is pathogenic to most domestic animals, except birds, the chief lesions found after death being fatty degeneration of the liver, hematogenous gastro-enteritis, * Centralbl. Baht. u. Par , lta Abt., xxi. (1897) pp. 561-72 (1 pi. and 56 figs.).. t Tom. cit., pp. 129-33. X Brit. Med. Journ., 1897, ii. pp. 7-11 ; and Ann. Inst. Pasteur, xi. (1897) pp. 433-514 (9 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 331 splenic tumidity, and parenchymatous nephritis. The toxin, which is prepared by simply filtering broth cultures 24 days old, when injected into some animals, gives positive results, and in man reproduces typical yellow fever (amarillism). The toxin is scarcely affected by heating to 70°, though boiling sensibly attenuates it. The toxic power of cultures sterilised with ether is markedly increased. Bacillus icteroides, as the organism is named, is able to live on or in company with Hyphomycetes. This remarkable feature is easily demonstrable in cultures which are apparently quite dead. Dr. Havelburg * has found in the contents of the stomachs of persons dead of yellow fever at Rio de Janeiro a bacillus 1 fx long and from 0*3- 0*5 fx broad. It is easily stained, but not by Gram’s method. It grows easily on gelatin, which is not liquefied. The growth is white on gelatin, and also on agar. Bouillon becomes turbid in 24 hours, with the forma- tion of a grey cloudy sediment. Saccharated media are fermented, with the formation of gas. Milk is coagulated in 24 hours. Parasites of Vaccinia and Variola, f — M. P. Salmon infers, from his researches into the nature of the infective agent of vaccinia aud variola, that the appearances observed by himself and others merely simulate a parasite, and that this pseudo-parasite is nothing but a ball of chromatin more or less condensed and of no particular form. The pseudo-parasite is not of endogenous, but of extra-epithelial origin, being derived from the migratory polynuclear leucocytes, the nucleus of which becomes trans- formed into the vaccinia granules. A table giving the colour reactions of the epithelial cell, the parasitic corpuscles, and the polynuclear leucocyte, shows that the two latter bodies invariably exhibit identical colour appearances, and that the nucleole of the epithelial cell not infrequently corresponds. * Lancet, 1897, ii. pp. 59-60 ; and Ann. Inst. Pasteur, xi. (1897) pp. 515-22. f Ann. Inst. Pasteur, xi. (1897) pp. 289-307 (1 pi.). 332 SUMMARY OF CURRENT RESEARCHES RELATING TO MICROSCOPY. A. Instruments, Accessories, &c.* (1) Stands. Evolution of the Microscope.t — Mr. E. M. Nelson, on behalf of a sub-committee of the Quekett Microscopical Club, proposes in a series of articles : — (a) to investigate a good type of instrument ; ( b ) to give a study of modern instruments, showing wherein, and why, they either follow or depart from the selected type; (c) to collate the other material bearing on the development of modern Microscopes, though not falling within the limits of a and b. For the type, Powell’s No. 1 is to be taken, since to this the best modern Microscopes are more and more conforming ; and, as it has remained Fig. 21. in its present form for upwards of twenty years, it is a permanent type. In the present paper several old forms, which are of importance in the evolution of the Microscope, and which have probably influenced the design of Powell’s No. 1, are de- scribed. Figures are given of the instruments of Jansen (about 1660), Descartes (1637), Hooke (1665), Divini (1667), Cherubin d’Orleans (1671), Bonanni (1691), Hartsoeker (1694), and John Marshall (1704). Of importance are Hooke’s, Bon- anni’s, and Marshall’s. Simple Microscope for Direct Observation and for Photography.^ • — Herr C. Leiss describes the in- strument shown in fig. 21, which is made by Fuess. The arm o, sup- porting the lens, is rigidly fixed to the foot, and the stage and mirror are made movable. Above the lens the small camera T may be fixed by the screw S. For direct observation, and for photographs which need not be very sharp, ordinary Steinlieil lenses are used ; but for better photographic work, two photographic objectives of 41 and 25 mm. focus are supplied; these fit into the arm o. * This subdivision contains (1) Stands; (2) Eye-pieces and Objectives; (3) Illu- minating and other Apparatus; (4) Photomicrography; (5) Microscopical Optics and Manipulation ; (6) Miscellaneous. t Journ. Quekett Micr. Club, vi. (1897) pp. 349-56 (9 figs.). X Zeitschr. f. angew. Mikr., iii. (1897) pp. 39-40 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. n oo OOO The stage has an aperture of 35 mm. diameter, and a smaller diaphragm can be laid over it if wished. A blackened disc e shuts off or admits light when photographing. A tabic of the focal lengths of the lenses used, amplifications, times of exposure, &c., is given. Hand-Microscope.* — The accompanying fig. 22 represents a Hand- Microscope made by C. Reichert; it is simpler and more convenient than many other demonstration instruments to be handed round in an audience. The tube slides easily in the sleeve, and, if necessary, can be replaced by another giving higher magnification. The extension of the stage is for carrying a drawing of the object shown. Stand and Illuminating Apparatus for Opaque Objects.f — HerrC. Reichert describes the instrument shown in fig. 23. The stand, with coarse and fine adjustment, is hinged to the heavy foot ; the stage is of white glass, with a white background. Light passes through the tube * Zeitschr. f. angew. jMikr., iii. (1897) pp. 44-5 (1 fig.). t Tom. cit., pp. 40-1 (1 fig.). rihe same instrument is also described by Prof. A. Rejto, Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 1-4 (1 fig.). 334 SUMMARY OF CURRENT RESEARCHES RELATING TO Z>, which is fitted with an iris-diaphragm, and is reflected by a mirror at a on to the object. The instrument is especially designed for studying the structure of etched and fractured surfaces of metals and alloys; it will also be useful for observing the surface characters of minerals, rocks, &c. (3) Illuminating- and other Apparatus. Improved Illuminating Apparatus.* — Herr C. Eeichert describes an improved form of the Abbe substage illuminating apparatus, of * Zeitschr. f. angew. Mikr., iii. (1897) pp. 33-5 (4 figs.). Cf. this Journal, 1896, p. 373. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 335 which several modifications have been made since it was first introduced. The special point of the present form is that it is independent of the mirror; it can also he swung to one side and other accessories attached. Fig. 24. Fig. 25. The whole apparatus swings about the axis D (figs. 24 and 25), as shown by the outline drawings to the light, and I it has a vertical motion 336 SUMMARY OF CURRENT RESEARCHES RELATING TO by means of gearing T. On the upper part of the main arm is a sleeve into which the condenser C, or other accessory, fits. On the under side of the same arm the iris-diaphragm is carried by the pivoted arm d, and can be swung out of position as shown on the left. For oblique illumination the diaphragm may be moved from side to side by the rack Fig. 26. Fig. 27. and pinion t. The whole apparatus is held in a central position by a pin, which projects from the under side of the stage, fitting into the hole a , when the apparatus is screwed upwards by the arrangement T. In cases where it is necessary to quickly change from convergent to parallel light, the condenser and diaphragm are hinged together, as is shown in figs. 26, 27. Owing to the size of the apparatus, it can only be fitted to the larger stands. Coloured Illumination.* — Mr. J. Kheinberg describes a new form of “ sub- stage differential colour illuminator,” con- sisting of a box containing nineteen metal slides, which can be moved in or out independently of one another by means- of small handles. Each slide has two circular apertures, one of which is fitted with a colour disc or other stop. The kind of stop is indicated on the handle. When the slides are pushed in, only the blank apertures are in the path of the light, but when pulled out, one or other of the stops is brought into use. The stops for giving coloured backgrounds, and for illuminating the object with various stops, include a dark-ground stop, various colours, parti-coloured stops, stops for oblique light, several annuli, and a ground-glass stop. The various combinations of stops which can be brought into use are almost endless. Portable Microscope Lamp.t — Mr. W. Goodwin has designed a lamp made by Mr. Hinton (fig. 28). The metal chimney has two circular aper- tures 1 in. in diameter, one of which is glazed with signal green and the * Journ. Quekett Micr. Club, vi. (1897) pp. 346-7. f Tom. cit., p. 345 (1 fig.). Fig. 28. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 337 other with steel-blue glass. The cylindrical reservoir is 2 in. diameter, and the total height of the lamp is 7 in. A blotting-paper wick is used. Simple Instrument for Inclining a Preparation in the Micro- scope.*— Mr. T. A. Jagger, jun., has devised an instrument for use in petrography, especially in connection with the optical methods of Michel-Levy and Fedorow for the determination of felspars ; it will also be of use in cases where it is necessary to examine the edges of objects in reflected light. The object-holder clip is supported by a ball-and-socket joint on a foot-plate, which may be fitted to the stage of the Microscope. This allows the object to be turned into any desired azimuth, and the various minerals in rock sections can then be brought into definite orientations, as is done in the more complicated “ universal stage ” of Fedorow. The optic figures seen in convergent polarised light may also be brought into the centre of the field of view. Modification of the Automatic Gas-Stop for Extinguishing the Burner of Incubators.f — Dr. B. Schiirmayer has devised a modification of the gas-stop to incubators which prevents the escape of gas and the danger of its exploding. The supply tube is fitted with a metal spiral lever which acts on a stopcock, so that if there be any fault in the work- ing of the apparatus beyond this point, and the gas supplied to the burner fail, the lever acts on the stopcock, and thereby prevents further access of gas to the apparatus. The most important feature of the in- vention is that all the parts of the apparatus are of metal. Slide and Cover-Glass Holders.^ — Herr S. Robertson has devised holders for slides and cover-glasses, the construction of which may be Fig. 29. grasped from an inspection of the illustrations (figs. 29 and 30). The former is merely a spring-forceps made of nickelled wire, the inside of the fangs being grooved for the reception of the slide. The cover-glass * Amer. Journ. Sci., iii. (1897; pp. 129-31 (2 figs.), t Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 400-1 (1 fie.X % Tom. cit., pp. 589-91 (2 figs.). 338 SUMMARY OF CURRENT RESEARCHES RELATING TO forceps lias a trifurcate lower fang between which the slip is inserted. The two upper teeth of the fang are grooved, and are set at a right angle, so that a square cover fits in accurately., and is held firmly by the upper fang. (4) Photomicrography. Photomicrography. ' — Mr. T. J. Bray considers the practical employ- ment of ordinary objectives in photomicrography; he shows that for ordinary work it is not really necessary to have specially corrected lenses, and that with ordinary objectives of low power good results can be obtained. The objective he finds most useful is Bausch and Bomb’s student’s 3 in. to 6 in. variable ; this with a long bellows camera gives a wide range of amplification, which may be further increased by the usual methods of photographic enlargement of the negative. For large nega- tives a dark room takes the place of the camera, the Microscope and light being arranged outside. With the long bellows camera, the focusing arrangement of Dr. Mercer is adopted. This consists of a wire from the back of the camera, which is connected by a vertical lever to a horizontal extension of the pinion shaft of the Microscope coarse-adjustment. The picture is focused, with the aid of a 2 in. eyc-pieco, on thin cover-glasses cemented on the ground-glass screen of the camera, as is done by Walms- ley. Many details can only be brought out by using a colour screen ; this is a bichromate cell, as is used in cloud photography. Photographic details are given in the paper. Acetylene Gas in Photomicrography, j — Mr. W. H. Walmsley has previously suggested the use of acetylene gas as an illuminant in photo- micrography/! The light which it gives is white, very brilliant, and absolutely steady ; there is little heating and no smell ; it is portable, simple, cheap, and safe, and is always ready for use. All these advan- tages are not combined in sun, lime, magnesium, electric, or other lights. The flame, which consumes one-tenth to one cubic foot of gas per hour, is enclosed in a metal case with a glass front ; the flat flame is placed end on, or pencil flames are placed behind each other with diaphragms between. The author, for his own use, renders the light monochromatic by means of a cobalt blue cell placed in the substage of the Microscope. The use of an acetylene flame as a standard unit of light is suggested. An automatic machine for generating the gas from calcium carbide is supplied by Walmsley, Fuller & Co., of Chicago. Astronomical Photography with Photomicrographic Apparatus.§ — Dr. A. C. Mercer obtained photographs of the partial eclipse of the sun seen at Syracuse, N.Y. on Oct. 20, 1892. The heliostat and a portrait lens of 8 in. focus were arranged to throw a stationary image of about 1/12 in. diameter of the sun’s disc in the plane usually occupied by the object on the stage of the Microscope. This image was projected by a 1J in. Microscope objective to form a second image, 2§ in. diameter, on the ground-glass of the camera. As far as compactness is concerned, this arrangement is more convenient than telescopic methods, but it is in- ferior in illumination and separating power. The results obtained are * Trans. Amer. Micr. Soc , xviii. (1897) pp. 107-16. f Tom. cit., pp. 136-41. X Cf. this Journal, 1896, p. 126. § Trans. Amer. Micr. Soc., xviii. (1897) pp. 132-5 (2 figs.). 339 ZOOLOGY AND BOTANY, MICROSCOPY, ETC. compared numerically with those obtained with the Lick photographic objective. Photomicrograph v. Microphotograph.* * * § — Dr. A. C. Mercer, in the present note on his paper of 1886, points out that the word photomicro- graph was first used in 1858. An account of its origin is to be found in the ‘Liverpool and Manchester Photographic Journal’ (now ‘ British Journal of Photography ’), August 15, 1858, pp. 203 and 414 ; also in 1 Sutton’s Photographic Notes,’ iii. pp. 205 and 208. Advances in Photomicrography. t — Herr G-. Marktanncr-Turneret- scher collects together under this title a series of abstracts of recent papers relating to Photomicrography ; these have already been noticed in this Journal. (5) Microscopical Optics and Manipulation. Multiple Images in Mirrors.J — Mr. W. B. Stokes explains the origin of multiple images seen in plate-glass mirrors. The brightest image is due to reflection from the silvered back, another to reflection from the front glass surface, and others are due to more than one reflection within the glass. When the mirror is rotated in its own plane, these images will change their position, owing to the fact that the surfaces of the plate are not truly parallel. For a particular angle of inclination of the two surfaces of the plate, the first two images may be made to coincide. 33. Technique. § (1) Collecting- Objects, including- Culture Processes. Apparatus and Method of Manipulation for the Preparation of Roll Cultures of Anaerobic Organisms. ||-In using the apparatus invented by Mr. E. E. Ewell (fig. 31), the tube is inoculated with the requisite number of organisms in the usual way, and is placed in the water-bath B, the temperature of which is kept at some convenient degree between the solidifying point of the medium and the thermal death point of the organism to be cultivated. The cotton plug P is pushed into the tube to make room for the rubber stopper carrying the glass tubes a and a\ The stopper is carefully sealed with sealing-wax, and the connections made with the thick rubber tubes N and 0, the latter being secured with wire. E leads to a vacuum service pipe, or to some form of vacuum pump ; F leads to a hydrogen gas generator. I and H being closed, open L until the air is removed, then close L and open H. The mercury con- tained in the bottle 0 passes up the tube D until an equilibrium is established where the point at which it comes to rest is marked. If all parts of the apparatus are tight, the column of mercury will remain stationary ; if it falls, all the connexions must be re-examined. In order * Trans. Amer. Micr. Soc., xviii. (1897) p. 131. Cf. this Journal, 1887, p. 665. t Jalirb. f. Photographie u. Reproductionstechnik, 1897, 12 pp. and 4 figs. j Journ. Quekett Micr. Club, vi. (1897) pp. 322-4 (3 figs.). § This subdivision contains (1) Collecting Objects, including Culture Pro- cesses ; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; (4) Staining and Injecting; (5) Mounting, including slides, preservative fluids, &c. ; (6) Miscellaneous. 11 Centralbl. Bakt. u. Par., 2te Abt., iii. (1897) pp. 188-90 (1 fig.). 340 SUMMARY OF CURRENT RESEARCHES RELATING TO to remove all j)0ssibility of leakage around the stopper A, the flame of a Bunsen’s burner is applied to the sealing-wax until it is sufficiently softened for the pressure of the atmosphere to force it into any crevice that it has not reached. When the column of mercury in D becomes stationary, admit hydrogen by means of I, until the vacuum in A is Fig. 31. destroyed. Close I and Id and open L until exhaustion is complete ; close L and open H and I successively. The alternate exhaustion and tilling are repeated until there is no possibility of any air remaining in A, when the tubes a and a! are drawn apart and sealed in the flame. In order that the pressure within A may be only very slightly different from that of the atmosphere, H is not opened after the last exhaustion. ZOOLOGY AND BOTANY* MICROSCOPY* ETC. 311 I is opened, and when the acid reaches the same level in both parts of the gas generator, quickly close M, and then close I just as soon as the change of level in the generator shows that there is a slight excess of pressure in A. After sealing, the tube is transferred to the ice block and rolled until the agar or gelatin is solidified. In case of agar, the rolling must be very rapid to ensure good results. The apparatus is also of service for displacing the air from other forms of anaerobic cul- ture apparatus. If the vacuum pump used is capable of giving a column of mercury 635 millimetres high in the tube D, five-sixths of the gases in the tube A will be removed at each exhaustion. A simple calcula- tion will satisfy the operator in regard to the number of exhaustions necessary. Preparation of Culture Media and their Sterilisation.* — Mr. R. C. Reed recommends the following methods for the preparation of nutrient media. Pejotonised Bouillon. — To 1000 grm. of finely divided meat, add 2000 grm. of distilled water, and place in an agate or iron dish, and then heat in a water-bath at from 60°— 65° C. for two hours, or allow it to macerate in a cool place for 24 hours. Strain through a coarse cloth, and bring the amount of liquid up to 2000 ccm., adding water if necessary. Then add 0*5 per cent, pepton, and 0*5 per cent, sodium chloride ; and, if a neutral or alkaline medium be desired, add enough of a 1 per cent, solution of caustic soda. Boil in a water-bath for half an hour. Cool, and filter through ordinary filter paper, and distribute in sterilised flasks. Nutrient Agar. — Dissolve 5 grm. of finely cut agar in 100 ccm. of water, and then add it to 500 ccm. of bouillon and boil for 20 minutes. Cool down to 45°-50° C., and add the whites of two eggs. Return to the water-bath and boil for 20 or 30 minutes. In this way the clot will be got rid of, and a perfectly clear liquid left. Filter through ordinary filter paper wdiile hot, and distribute into sterilised tubes. Nutrient Gelatin. — To 500 ccm. of bouillon add 50 grm. of gelatin, and heat in a water-bath until the gelatin is dissolved. Cool to about 45° C., and then add the whites of two eggs, mixing the lot thoroughly. Boil in a water-bath for about 20 minutes. Filter, and distribute in sterilised tubes. Care must be taken not to boil the gelatin too long, lest it will not set when cold. The author goes on to point out that lengthy discontinuous sterilisa- tion may be overdone ; for he has found that sterilising for one day for 30 minutes usually suffices. All that is necessary is to incubate afterwards for several days, and then reject the few tubes which are contaminated. Rapid and Easy Method for Preparing Nutrient Agar.f — Herr E. S. London prepares agar in 33 minutes in the following way : — To 1 litre of meat water are added 5 grm. of salt, 10 grm. of pepton, and 15 grm. of agar, and the mixture placed in a flask which is heated in an autoclave until the temperature rises to 130°. The steam is then gradually slacked off, and when the temperature has sunk to 100° the * Amer. Monthly Micr. Journ., xviii. (1897) pp. 149-54. f Centralbl. Bakt. u. Bar., lte Abt., xxi. (1897) pp. 686-7 2 A 1897 342 SUMMARY OF CURRENT RESEARCHES RELATING TO flask is removed, and its contents filtered through a Diakonow’s appara- tus. The clear filtrate is then poured into flasks and neutralised. For Diakonow’s apparatus may be substituted a simple arrangement con- sisting of a flask, the neck of which is closed by a caoutchouc plug with two holes. One of the holes receives the stem of a filter ; the bottom of the hopper is covered with a piece of gauze upon which is placed a layer of glass wool and then a layer of fine sand. To the second hole is fitted a bent glass tube connected with an exhaust pump. Apparatus for Cultivating Yeasts on Plaster Blocks.* — M. H. Schionning has, by combining the advantages of the plaster block and a Hansen’s flask, devised an ingenious apparatus for obtaining pure ascosporous cultures of yeasts. A cylindrical block of plaster, reach- ing to about two-thirds up the flask, and made by mixing 2 volumes of plaster with 3/4 volume of water, is fixed to the bottom of the flask. The top of the plaster pillar is slightly hollowed for the reception of the yeast. The side tube having been plugged with cotton- wool, the apparatus is sterilised at 115° for an hour and a half. When cooled, the cap is removed and the culture placed in the hollow on the top of the pillar. The cotton-wool plug is then removed, and through the lateral tube sterilised water is introduced in quantity sufficient to reach half- way up the plaster cylinder. When the top of the pillar shines from imbibition of water, the whole apparatus is incubated at a temperature favourable for the production of spores. A piece of rubber tubing is previously fitted on the lateral tubulure, its free end being plugged with cotton-wool. By this procedure, perfectly pure cultures, quite free from bacteria and other contamination, are easily possible. Amoeba Cultures.! — Dr. 0. Casagrandi and Dr. P. Barbagallo report on the different kinds of media suitable for Amoeba cultures, on the re- action of the substrata, on the necessity for the presence of organised constituents therein, and on cultivable and non-cultivable Amoebae. With regard to fluid media, there is no doubt, they say, that Amoebae will develop in hay, straw, and hemp infusions, on decoction of faeces, and in thin albumen ; but it is practically impossible to obtain a pure cultivation, partly owing to the difficulty of sterilising the medium, and partly on account of the impurity of the inoculation material. Of solid media, egg-albumen with some pepton and carbonate of soda was found extremely serviceable. Media composed of the above mentioned infusions solidified with agar or gelatin were failures. A medium containing 5 per cent, of Fucus xrispus was found to possess the advantages of inhibiting the growth of bacteria, and of affording opportunity to the Amoebae of completing the stages of iheir life-cycle. The most suitable reaction was found to be slightly alkaline to neutral ; strongly alkaline or acid reaction being unfavourable. Acidity of the medium did not, however, prevent certain species, such as A. coli , from becoming acclimatised to the reaction. With regard to the asso- ciation of protozoa, bacteria, fungi, and yeasts, with Amoeba in the cultures, which some observers seem to regard as necessary and irremov- * Ann. de Micrographie, ix. (1897) pp. 191-8. f Otntralbl. Baht, u. Par , lt9 Abt., xxi. (1897) pp. 579-89. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 343 able evils, the authors, while acknowledging the difficulty of obtaining pure cultivations, do not seem to consider this as impossible. From faeces were obtained cultures of A. coli, A. guttula , A. spinosa ; from Blatta-ex crement, A . blattarum ; from muddy water, A. guttula , nodosa , diffluens, arborescens, gracilis , spinosa, and oblonga ; from damp earth in unhealthy places, A. guttula, spinosa, and arborescens ; from beer yeast, A. guttula and spinosa. Culture Medium for Algse and Amoeba.* — Dr. N. Tischutkin recom- mends 1 percent, aqueous solution of agar for the cultivation both of Algae and of Amoebae. Crystal Formation in Culture Media. -j* — Dr. Marion Dorset regards the early formation of crystals in freshly prepared agar as a special characteristic of Bacillus pyocyaneus. Other bacteria produce crystals in culture media, but only when the media are old, and therefore partially dried. (2) Preparing- Objects. Methods for Demonstrating the Continuity of Protoplasm.} — In discussing the various methods adopted for demonstrating the continuity of protoplasm, Herr A. Meyer first makes a few remarks on fixation Of the tissue. For this 1 per cent, osmic acid is recommended, though strong iodopotassic iodide (iodine 3, iodide of potassium 3, water 20) and potassium-bismuth iodide solutions give favourable results. For soften- ing membranes sulphuric acid is the best agent (H2S04 1 vol. to O’ 5-3 vols. water). A very strong solution of iodine made by dissolving 1 vol. of iodine and 1 of iodide of potassium in a few drops of water, and then adding 200 ccm. of water, is useful occasionally for staining the threads of protoplasm. By staining with Hoffmann’s blue or Bavarian blue, the continuity of the protoplasmic processes was rendered distinctly visible. The sections were placed for a few minutes in a solution of 1 grm. of pigment and 150 grm. of 50 per cent, spirit, and examined in glycerin. Permanent preparations can be made from tissue fixed and hardened in osmic acid or alcohol by over-staining the sections in Delafield’s haema- toxylin (24 hours), and, after washing in 60 per cent, spirit, decolorising in 0 • 5 per cent. HOI. The sections must then be immersed in 60 per cent, spirit rendered alkaline by the addition of ammonia (10 drops to 100 ccm.). After this they are transferred to absolute alcohol, xylol, and mounted in balsam. A method for staining after mordanting with iodine is described at some length. The reagents required are : — • (1) Iodopotassic iodide solution (iodine 1, iodide of potassium 1, water 200) ; (2) sulphuric acid (1-3), which has been saturated with iodine by standing over some iodine ; (3) a solution of 1 grm. of pyoktanin coeruleum (Merck) in 30 ccm. of water. The sections are immersed in solution 1 for some minutes, and then placed on a slide and covered with a slip. Solutions 2 and 3 are added at the side of the cover ; and having been allowed to act for about three minutes, the slide, section and cover- glass are immersed in a large quantity of water. Having been quickly washed, the section is placed on a clean slide and examined in glycerin. * Centralbl. Bakt. u. Par., 2te Abt., iii. (1897) pp. 183-8. t Op. cit., lte Abt., xxi. (1897) pp. 473-4. X Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 166-77. 2 a 2 344 SUMMARY OF CURRENT RESEARCHES RELATING TO If the staining has been successful, the membrane is pale blue, while the protoplasm and its connections are blackish blue. Rapid Method of making Permanent Specimens from Frozen Sec- tions by the Use of Formalin.* — The method described by Dr. T. S. Cullen is as follows : — A piece of the fresh tissue is sectioned on an ether freezer, and the sections placed in 5 per cent, solution of formalin for 3-5 minutes, then in 50 per cent, alcohol for 3 minutes, and in absolute alcohol for 1 minute. Wash in water; stain in liEematoxylin for 2 minutes ; decolorise in acid alcohol ; rinse in water. Stain with eosin ; transfer to 95 per cent, alcohol ; then pass through absolute alcohol, creosote or oil of cloves, and mount in balsam. Or as an alternative method, should it be desired to retain the blood in the sections, a piece 1x5x2 cm. is placed in 10 per cent, formalin for 2 hours, after which the procedure is as before. (3) Cutting-, including Imbedding and Microtomes. Simple Microtome for Biological Work.| — Mr. A. Flatters de- scribes an improved form of the simple microtome originally designed by him. The carrier is moved upwards in the cylindrical well by a screw carrying at its lower end a notched disc, against which works a clicking arrangement ; three of these discs with different numbers of notches may be used, so that sections of any desired thickness may be cut. The aperture of the razor plate is, on the under-side, of the same diameter as the well, but on the upper side it is slightly less, this being for the purpose of firmly holding the imbedded mass in position as it is screwed up. The razor plate, which is held in position over the well by a clamp, may be swung on one side to enable the uncut material to be removed. For larger or longitudinal sections a special razor plate, with a rectangular aperture and a corresponding holder, may be fitted to the instrument. (4) Staining and Injecting. Simple Method for Contrast-Staining Micro-Organisms.* — Dr. Clau- dius stains microbes on covers and in sections by the following pro- cedure. The reagents used are (1) 1 per cent, aqueous solution of methyl-violet ; (2) 1 vol. of saturated aqueous solution of picric acid plus 1 vol. of water ; (3) chloroform ; (4) oil of cloves. Cover-glass prejjarations are stained in the methyl-violet solution for 1 minute, washed in water, mopped up on blotting-paper, immersed in the picric acid solution for 1 minute, washed and mopped up again, then decolorised in chloroform, and, after having been dried, mounted in Canada balsam. Sections are stained and treated very similarly, but the two solutions are used for two minutes instead of one ; and, after having been very carefully mopped up, are decolorised by means of oil of cloves, after which they are passed through xylol, and then mounted in balsam. Twenty-six species were tried by this method : 17 were stained and 9 were not ; among the latter being B. typhi, B. coli com., Sp. cholerse asiat., Pneumobac. Friedlaenderi. * Bull. Johns Hopkins Hosp., viii. (1897) pp. 108-9. t Pharmaceutical Journ , lviii. (1897) pp. 485-6 (4 figs.), f Ann. Inst. Pasteur, xi. (1897) pp. 332-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 345 Staining Vegetable Sections.* — Prof. F. D. Kelsey recommends that vegetable sections should be stained with pigments dissolved in clove oil. After staining, remove to pure clove oil or Gage’s fluid, and mount in balsam. It is hardly necessary to point out that the section must be perfectly dehydrated before it is immersed in the clove oil stain. A dilute clove oil stain acts better than a concentrated one. Method of Staining the Malaria Flagellated Organism.f — Dr. P. Manson has succeeded in staining the flagellated malaria parasite by the following method, which shows the pigment and certain details of struc- ture with ease and certainty. Thirty or forty strips (3 by 1J inches) of thick blotting-paper, each having an oblong hole (1 by inch) cut lengthwise in its centre, are prepared. They are then slightly moistened with water and laid in rows on a sheet of window glass. A droplet of blood, the size of a large pin’s head, is then obtained by puncturing the finger of a person in whose blood the crescent form of the malaria parasite abounds. A Microscope-slip is then breathed on once, and the droplet of blood dabbed on the centre of the breathed-on surface. The blood is then spread out with a needle so as to cover an area of f by h inch, and the slip immediately inverted over a blotting-paper cell. The slip is then pressed down, care being taken to prevent the blood coming in contact with either the wall of the cell or the floor of what is now a very perfect moist chamber. In from half to three-quarters of an hour the slips are removed, and dried by gently warming them over a spirit-lamp. When dry, the films are fixed with absolute alcohol. After five minutes the alcohol is dried off, and a few drops of acetic acid (10-20 per cent.) are laid on the film, and left long enough to dis- solve out the haemoglobin. The slips are then washed in water and dried. After this they are stained with 20 per cent, phenol-fuchsin, the stain being dropped on and the slip covered with a watch-glass. After six hours it is washed off, the slide dried, and a cover-glass applied with xylol-balsam. Most of the slides will show numbers of spheres and several or many well-stained flagellated bodies. Very few crescents remain untransformed. If the slips are removed and dried in from five to ten minutes after being placed on the blotting-paper cells, only crescents, ovals, and spheres will be found ; if left for more than three- quarters of an hour, free flagella and spent pigment may be found. Staining Diphtheria Bacilli.^ — Dr. C. F. Craig states that Crouch of Denver has found that, if 24 hours old culture of diphtheria be treated for a few seconds with 1 per cent, methyl-green solution, the majority of the bacilli will be faintly stained green, and will show at both ends a well defined round body of a distinctly red colour. The following solu- tion was found to be very serviceable : — 1 per cent, methyl-green, 5 parts ; 1 per cent, solution of dahlia, 1 part ; distilled water, 4 parts. Only a second is required for staining ; if left in longer, the staining is too intense. Combination of Weigert’s Fibrin Method and the Tubercle Bacillus Stain.§ — Herr Roloff stains tubercle bacilli and fibrin in the same section * The Microscope, v. (1897) p. 69. t Biit. Med. Journ., 1897, ii. pp. 68-70 (15 figs.). X Trans. Amer. Micr. Soc., xviii. (1897) pp. 274-5. § Arb. a. d. Pathol.-Anat. Inst, zu Tubingen, ii. (1896) p. 261. See Centralbl. Bakt. n. Par., lte Abt., xxi. (1897) p. 749. 346 SUMMARY OF CURRENT RESEARCHES RELATING TO by the following procedure. The sections are stained for twenty-four hours in an incubator in carbol-fuchsin, and then decolorised with Ebner’s fluid. After having been washed in 70 per cent, spirit, they are trans- ferred to acetic acid vesuvin solution (Kahlbaum) for some hours. Next they are washed in water and in 70 per cent, spirit, and are then stuck on a slide, after which they are stained by Weigert’s method. The anilin-xylol should be allowed to act for some time, otherwise the nuclei will be blue instead of brown. If the differentiation be successful, the nuclei are brown, the fibrin blue, the tubercle bacilli red, and other bacteria blue. (5) Mounting-, including- [Slides, Preservative Fluids, &c. To Prevent Freezing of Formol.* — Dr. A. Milani finds that the addition of 25-35 parts of glycerin to the formol solution prevents the danger of freezing. (6) Miscellaneous. , ; Eapid and Improved Method for Counting Plate Colonies.f— Dr. H. J. van’t Hoff has devised the following method for counting bacterial colonies on plates : — On the middle of a gelatin plate having a diameter of about 15 cm. is dropped about 0*2 ccm. of water. The water is then distributed over the surface of the gelatin by merely rolling the capsule about, care being taken to prevent the water from reaching the side. Distributed in this way, the colonies develop quite separately, and so rapidly that in two days it is possible to obtain a better quantitative result by this method than in five or six days by the ordinary procedure. Method for Examining Malarial Blood. f — Dr. N. Macleod uses strips of ordinary note-paper 0*5 in. wide and about 1J in. long for smearing cover-glasses with malarial blood. The straight edge is drawn its full half inch through a drop of blood not larger tjian a pin’s head, and then the edge drawn across the cover-glass. In this way a thin film which dries very rapidly may be spread on cover-glass or slide. The film must be mounted dry. With a 1/4-in. objective crescents and the larger pigmented parasites, and with a 1/12 oil immersion the smaller pigmented forms, can be easily seen. The method, however, cannot be relied on for the detection of unpigmented forms without very con- siderable experience, and should be supplemented by staining, or the examination of fresh undried films. Bacteriological Diagnosis of Leprosy.§ — The method advocated by Messrs. Johnston and Jamieson for the bacteriological diagnosis of leprosy is extremely simple, and consists in smearing a cover with a drop of serum obtained by scraping one of the leprosy nodules. This is stained with carbol-fuchsin, and decolorised with sulphuric acid and methylen-blue. The bacilli of leprosy are found in large numbers, and this fact alone is sufficient to distinguish leprosy from tubercle bacilli. Lepra bacilli also stain readily with simple anilin dyes, while tubercle bacilli do not. * Zool. Anzeig., xx. (1897) pp. 206-8. t Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 731-3 (1 fig.). X Lancet, 1897, ii. pp. 85-6. § Montreal Med. Journ., 1897. See Epit., Brit. Med. Journ., 1897, p. 92. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 317 Diagnosis of Smegma and Tubercle Bacilli.* — Herren R. Bange and A. Trantenrotli state that tlie only satisfactory method for distin- guishing the smegma from the tubercle bacillus is the following : — Immersion in absolute alcohol for not less than three hours, in 5 per cent, chromic acid not less than 15 minutes, in phenol-fuchsin, acid, sulph. dil. 2-3 minutes, and in saturated alcoholic solution of methylen- blue at least 5 minutes. Notes on the Agglutination Phenomenon of Typhoid Serum. — According to Widal and 8icard,j the agglutination phenomenon can be obtained with dead bacilli hilled by heat (57°-60°), or better still with certain chemical agents, such as formalin. By adding a drop of formalin to 150 drops of 1-2 days old typhoid culture, the bacilli are killed, though they perfectly retain their sensitiveness to the serum for a week. These authors also state if that from a drop of blood drawn from the finger and received into a sterile tube, a qualitative and quantitative test can be made. Ferrand § cites a case wherein the agglutination reaction with typhoid culture was obtained from the serum of a person who died of streptococcus septicaemia, and Nicolas || states that the same phenomenon occurs in patients who have been treated with antidiphtheritic serum. Dr. M. W. Richardson f finds that dried typhoid serum acts well for the purpose of diagnosing typhoid cultures from those of B. coli com- munis, B. pyogenes foetidus, and mouse typhoid. It is only necessary to take blood from the heart of a person dead of typhoid fever, and after obtaining the serum, pour it through a filter paper and dry it. Dr. W. Johnston ** confirms the value of Pfahl’s modification of Widal’s test ; in this the dried blood of a patient suspected of enteric fever is dissolved in water. Kolle || states that the virulence of the culture should always be taken into consideration, as normal serum in dilutions of 1-10 or 15 often produces an agglutinative effect on cultures which are but slightly virulent. Photometric Determination of Heliotropic Constants.!! — Prof. J. Wiesner recommends that the measurement of the heliotropic source of light should be determined by the photochemical method and the Bunsen- Roscoe unit of measure. In this way the intensity of those rays which act on silver chloride may be measured. The values obtained are gene- rally comparable; for they hold good for gaslight, electric light, and daylight. By this method it was determined that organs very little heliotropically sensitive will even react to a fraction of a millionth of the Bunsen-Roscoe unit. * Fortschr. d. Med., 189G, Nos. 23 and 21. See Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 353-4. f La Semaine Med., 1897, p. 38. t Tom. cit. p. 69. § Torn, cit., p. 30. || Tom. cit., p. 37. ^ Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 445-6. 511 * Tom. cit., pp. 523-6. ft Deutsche Med. Wochensclsr., 1897, No. 9. See Centralbl. Bakt. u. Par., I1* Abt., xxi. (1897) pp. 484-5. XX Bot. Centralbl., lxix. (1897) pp. 305-9. 348 PBOCEEDINGS OF THE SOCIETY. MEETING Held on the 16th of June, 1897, at 20 Hanover Square, W.? The President (E. M. Nelson, Esq.) in the Chair. In the absence of both the Hon. Secretaries, the minutes of the meet- ing of May 19th last were read by Mr. J. J. Yezey, and having been duly confirmed, were signed by the President. The List of Donations to the Society (exclusive of exchanges and reprints) received since the last meeting was read, and the thanks of the Society were voted to the donors : — From A. C. Abbott, M.D., The Principles of Bacteriology. (3rd edition, 8vo, Philadelphia, 1895) j Rev. TF. Arthur Bird. Aanteekeningen van de Sectie-Vergaderingen 1896. 1 La Societe provinciate des Arts Yerslag der Algemeene Vergaderingen 1896 .. J et Sciences e'tahlie a Utrecht. The President said the Fellows would remember that they had already had two exhibition meetings — in April and May — which he believed were very much appreciated by those who were present ; the success of those meetings was due in no small degree to the fact that a large number of excellent Microscopes were then placed at the disposal of the Society by Messrs. Beck and Mr. Baker ; on the present occasion the Microscopes upon the table had been provided by Messrs. Watson & Son ; and he thought the Fellows present would be very pleased to join in passing a very hearty vote of thanks to the members of these firms for bringing down so large a number of good instruments, and in this way enabling the Society to give such fine exhibitions. The motion having been put from the chair, was carried by acclama- tion. The President said he had brought down to the meeting a few things which he thought might be of interest to those present. The first of these was a series of photographs of microscopic objects enlarged from some of his own negatives, the point about them being that they were all enlarged to make pictures of the same diameter, the magnifying power being indicated below each. Most of them had stood this ampli- fication fairly well, but they began to go off a little after from 7000 to 7500 diameters had been reached. The next thing was one of his lens-mirror loups ; this was practically the same thing as he had previously exhibited, so far as its optical con- struction and magnifying power were concerned, but it had the mirror PROCEEDINGS OF THE SOCIETY- 349 added, and this rendered it very effective and useful when illuminated by daylight, or by the flame of a paraffin lamp. Unfortunately, it was of little use in that room, as the incandescent filament of an electric lamp was quite unsuitable for this hind of illumination. The other item which he had brought to show them was a new Micro- scope lens, viz. a semi-apochromatic 1/10 of 1*3 N.A. by Leitz corrected for the long tube. The optical index of this lens was 13, against 10 of the old semi-apochromatic 1/12, and 17 of Zeiss’ apocliromatic 1/8 of 1-4 N.A. He said that, in looking back upon the past, it will be readily con- ceded that the greatest revolution in the history of the Microscope was caused by the introduction of achromatism ; but if the period was limited to the recent past, it might be said that a new epoch began with Prof. Abbe’s invention of apochromatism. His own opinion, however, was that the production of the new Jena glasses which enabled semi-apochromatics to be constructed, wos of equal, if not greater, importance to microscop- ists than the introduction of apochromatism. Apochromatism under present conditions required the use of fluorite, a rare mineral, and one difficult to work, consequently apochromatics were expensive ; but here we had a lens before us, the optical qualities of which were only slightly below those of the best apochromatics in existence, and yet its price was SI. 15 s. Of course the resolving power of this lens was less than that of the 1*4 apochromat in the proportion of 13 to 14, but he doubted whether there was any ordinary test-object which a 1 *4 apochromat would resolve, that this objective would not resolve also. The introduction of such an ex- cellently corrected semi-apochromat encouraged him in the hope that before very long he would be able to announce to them that the word “ semi ” might be omitted from the title of this class of objective. He had given this lens an exhaustive testing, and there were only one or two excessively difficult secondary diatomic structures in his pos- session which it failed to resolve. They could remember that a little time back he announced the dis- covery of a difficult structure on the hoop of a Navicula major ; that structure, which was so difficult with an apochromat of 1*4 N.A., was strongly shown by this lens. This indicates not only the advance made by the lens itself, but also the improvement in the methods of using modern wide-angled oil immersions. Mr. Vezey said that it had frequently happened at the last meeting of the session that they had no paper upon the Agenda. This was the case on the present occasion ; but they had upon the table for exhibition a large number of specimens of palates of Mollusca selected from the collection presented through Mr. Rousselet at the last meeting ; these being shown, as the President had already mentioned, under Micro- scopes kindly provided for the occasion by Messrs. Watson and Son. He also intimated that the Rooms of the Society would be closed from Monday to Wednesday, June 21st to 23rd inclusive, and that they would be closed for the usual vacation from August 13th to September 13th. 2 B 1897 350 PROCEEDINGS OF THE SOCIETY. Mr. Vezey also gave formal notice on behalf of the Council that the next meeting would be made special, to consider the desirability of adding the following bye-law to those in existence : — Bye-law 65 to read : — “ The Council shall, at the Annual Meeting, propose a Fellow of the Society to act as curator of the instruments, tools, and such other objects as may from time to time be confided to his care ; he shall be elected by the Society, and shall make an annual report of the condition of the objects under his charge.” The President, again reminding the Fellows that this was the last ordinary meeting of the session, wished them a very pleasant vacation, and hoped they would not only greatly benefit by their holidays, but would also endeavour to benefit the Society by obtaining materials for some good papers, and by doing what they could to induce new Fellows to join the Society when they met again in October. The following Instruments, Objects, &c., were exhibited:— The President : — A series of Photographs of Microscopic Objects en- larged from some of his own negatives. A Lens-mirror Loup, power 10. A 1/10 in. oil- immersion semi-apochromatic Objective by Leitz, N.A. 1 • 3, corrected for the long tube. The Society : — The following slides of Palates of Mollusca : — Ampul- laria fasciata , ditto sp., Bullia digitalis, Chiton siculus, ditto spiniger ? Chlorostoma brunneum , Cyprsea caput- serpentis, ditto cervinetta (young). Doris tuberculata , Helix Hopetonensis , Janthina rotundata, Labio zebra , Livona pica , Neritina punctulata, Paludomus phasicanus, Patella vulgata, Polydonta radiata, Siphonaria Zealandica , Trochus lineatus, Urosalpinx cinerea. New Fellows: — The following were elected Ordinary Fellows: — Mr. S. C. Mahalanobis, Mr. Frank Orfeur, and Dr. Ezra H. Wilson. NOV 4 1337 JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY. OCTOBER 1897. SUMMARY OF CURRENT RESEARCHES I Relating to Zoology and Botany (principally Invertebrata and Crypto- gamia), Microscopy, &c., including Original Communications from Fellows and Others * ZOOLOGY. ] VERTEBRATA. a. Embryology.! Recapitulation.^ — Mr. J. T. Cunningham discusses the recapitu- lation-doctrine, which he regards as “a hasty generalisation.1’ He begins with a brief note — too brief as regards von Baer — on the history of the idea, and then turns to Sedgwick’s recent criticism. A number of particular cases are discussed as tests of the recapitulation-theory, — the life-history of Amphibia, the development of the tail in fishes (whereon a considerable digression from the theme), and the development of flat fishes — and it may be allowed that the theory in its usual form does not stand the test very well. Finally, Mr. Cunningham discusses the “ re- capitulation ” of the eye in the development of the more or less blind animals which live in caves or in similar conditions. The recapitulation is very imperfect and incomplete. “ The following conclusions,” at least so the author says, “ follow necessarily from the facts.” (1) “ The blindness of cave animals has certainly not been produced by the selection or survival of individuals in which the eyes were de- fective from their first development. If it is due to selection at all, it is the selection of individuals in which the eyes underwent progressive deterioration after the commencement of independent life.” .(2) “ The eyes, even in the stage in which they are most developed, "are far from being as well developed as in the ancestors which lived in * The Society are not intended to be denoted by the editorial “ we,” and they do not hold themselves responsible for the views of the authors of the papers noted nor for any claim to novelty or otherwise made by them. The object of this part of the Journal is to present a summary of the papers as actually published , and to describe and illustrate Instruments, Apparatus, &c., which are either new or have not been previously described in this country. f This section includes not only papers relating to Embryology properly so called but also those dealing with Evolution, Development, and Reproduction, and allied subjects. % Science Progress, i. (1897) pp. 483-510, 1897 2 o 352 SUMMARY OF CURRENT RESEARCHES RELATING TO daylight, but are only somewhat more developed than in the adult animal. Recapitulation does not therefore occur except when the ex- ternal condition to which the ancestral structure was adapted continues to act at an early period of life.” The article is a very interesting one, but we cannot silence the wish that expert embryologists, such as the writer, would, in writing on re- capitulation, bring the discussion to a more definite focus. Is this recapitulation-doctrine, with its long pedigree going back far beyond von Baer, who was as much its critic as its exponent, and with its pro- longed and surely not wholly disastrous influence on embryology, an entirely mistaken interpretation ? If not, what precisely is wrong with it, and what restatement may for a time fill its place ? If yes, do we not require a franker confession of ignorance as to the meaning of such structures as the gill-slits of Mammals, and a more strenuous physio- logical embryology ? Regeneration of Organs in Amphibia.* — Prof. W. Kochs has ex- perimented with tadpoles of Rana fusca and Bombinator igneus , and also with salamanders and newts. He found a platinum needle and galvanic cautery the most serviceable instrument. Immediately after the operation the tadpoles swam about as if nothing had happened, and on the second day they ate white bread and frog-flesh as usual. When an eye was wholly destroyed, no hint of regeneration could be observed, even after three months. Kochs generalises this result in the conclusion that regeneration of an organ occurs only when a portion of the organ is left. The author cites some interesting historical notes from a paper by Y. Colucci which seems hardly to have received the attention it deserves. Thus Bonnet and Blumenbach proved the regeneration of the newt’s eye when a remnant was left in connection with the optic nerve ; Philip- peaux (1880) showed that no regeneration occurred (in 40 cases) when no remnant was left ; Colucci (1891) has priority over Gustav Wolff and Erik Muller in demonstrating the regeneration of an extirpated lens from a centre of formation situated in the anterior border of the iris. The experiments which Kochs himself made on this interesting question of lens-regeneration lead him to the suggestion that the new lens may arise from epidermic cells brought into the interior of the eye by the operation. He thinks it unlikely that the iris could remain quite uninjured by the operation, as Erik Muller maintains. This result is certain, that in tadpoles the lens is regenerated as it is in newts ; but a secure conclusion as to the precise formative tissue of the new lens is still to seek. In general, Kochs concludes that in regeneration a restitutio in integ- rum never occurs, the regenerated part being always smaller ; that in forms other than larvte there is during regeneration a hypertrophy of the part which compensates for that which has been removed ; that repro- ductive power is greater and more rapid when only small parts of the extremities are amputated. The appearance of extra parts is more probable, as Barfurth has shown, the nearer the amputation is to the proximal end of the appendage. * Arch. f. Mikr. Anat., xlix. (1897) pp. 441-61 (1 pi. and 3 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 353 Maturation and Fertilisation in Amphioxus.* — Dr. J. Sobotta has been able to make an essentially complete series of observations on tbe fertilisation-process in tbe eggs of Amphioxus lanceolatus. He also gives a detailed account of tbe formation of tbe second polar body,* but is unable to contribute anything to tbe question of reducing divisions. Tbe fertilisation processes conform to tbe usual plan ; tbe centrosomes of tbe fertilised ovum are wholly of paternal origin ; the chromatin is in half paternal and in half maternal ; no bint of a centre- quadrille or the like was to be seen. Tbe author finds bis results very different from those reached by 0. Van der Stricht, and believes that this careful Belgian investigator worked unconsciously with markedly polyspermic ova. Germinal Vesicle and Polar Bodies in Batrachia.j — MM. J. B. Carnoy and H. Lebrun began a study of these structures in 1887, and they speak of their patient work as ten years of bard labour. They start with a general essay on tbe structure of tbe cell, especially of tbe nucleus, comparing their own observations and conclusions with those of others. There are two other general chapters in tbe memoir, one entitled “ tbe karyoplasm and tbe cytoplasm,” and one dealing with nucleoli. Tbe first type discussed is Salamandra maculosa , in tbe eggs of which they find four types, characterised by tbe different resolutions of tbe nuclear filament. In order of frequency these types are : — (1) Besolution serpentine , (2) Besolution en houdins, (3) Besolution filamenteuse etoilee , and (4) Besolution en plumeaux. Tbe second type discussed is Pleuro- deles Waltii Mich. Here there are three types, characterised by tbe nucleolar figures of tbe first period. Ovary and Ovarian Ova in Marine Fishes.! — Mr. J. T. Cunning- ham deals especially with tbe development of tbe yolk. In fishes with pelagic ova and an annual spawning period, tbe formation of yolk com- mences some months after tbe close of tbe preceding spawning season. Tbe active development of tbe annual crop of ova does not take much more than six months. Tbe formation of yolk always begins near tbe surface of tbe cytoplasm, and extends inwards. If there are separate oil- globules, a few small ones are present before tbe yolk begins to be formed, except in tbe mackerel. In immature sole, turbot, brill, &c., examined during tbe spawning season, tbe largest ova in tbe ovaries con- tain scattered oil-globules. Tbe same is true in tbe largest transparent ova in spent ovaries of these species. When tbe formation of yolk takes place in such eggs, tbe oil-globules form a zone internal to tbe yolk. Tbe essential peculiarity of tbe spent ovary is tbe presence of rup- tured follicles ; tbe follicular epithelium seems to disintegrate and dissolve; tbe cavity is obliterated by tbe contraction of the follicle,, which forms a mass of cells and fibres, and is finally absorbed soon after yolk begins to be formed in tbe eggs of tbe following season. Some eggs which have never matured die. and are absorbed in situ. In tbe fresh state they are seen as opaque amorphous masses. Tbe same is true in unripe ovaries where spawning has never occurred. The vitelline nucleus is first seen as a stained corpuscle in contact * Arch. f. Mikr. Anat., 1. (1897) pp. 15-71 (4 pis.). t La Cellule, xii. (1897) pp. 191-295 (5 pis.). X Quart. Journ. Micr. Sci., xl. (1897) pp. 101-63 (3 pis.). 2 c 2 354 SUMMARY OF CURRENT RESEARCHES RELATING TO with the germinal vesicle ; it is probably identical with the centrosome which remains in the ovum after the last division of the germ-cell. In ova of plaice and flounder it moves to the inner border of the yolk-layer, and becomes surrounded with yolk. In Syngnathus acus there are often two or more vitelline nuclei in one ovum. The germinal vesicle in Teleostean ova shows at first a single large nucleolus, a nuclear network, and a membrane. At the next stage the vesicle is larger, and there are several peripheral nucleoli ; in still larger ova the nucleoli are still peripheral, but there is a central region with separate feathery fibrils, the centrosomes of Riickert. After the forma- tion of yolk has begun, the nucleoli are found around and among the central fibrils ; and in the turbot there are hints that the substance of the nucleoli is absorbed into the central fibrils to form the chromosomes of the polar mitoses. Development of Spermatozoa in Salamander.* — Dr. F. Meves has reinvestigated the much studied development of the spermatozoon in Salamandra maculosa. He attended particularly to the role of the central corpuscle and the sphere in the formation of the spermatozoon. That there is some relation between the middle part of the spermatozoon and the central corpuscle has been quite clear for several years. For in numerous cases it has been shown that after the spermatozoon enters the ovum, a radiate system develops around the middle part. From this the inference has been drawn that the middle part of the spermatozoon con- tained the centrosome. What Meves claims to have proved is that the middle part is formed wholly of centrosome-substance. Spermatogenesis in Selachians.^ — Prof. Armand Sabatier has pub- lished a lengthy memoir on the spermatogenesis of Selachians, as ex- hibited by Scyllium, Acanthias , and Raja. He compares his results throughout with those obtained in his study of Crustaceans. The origin of the germ-cells is the same in the two cases. They occur in groups or nests of nuclei lying in a plasmodium. These primary nests are formed by the direct division of the nuclei of the germinal connective tissue. Secondary nests are formed by the direct division of flattened nuclei contained in the connective membrane of the acinus or testicular cul-de-sac. The direct division occurs by pulverisation of the nuclein and by cleavage. The undivided protoplasm is disorganised. The nuclear germs are transformed into protospermatoblasts, each acquiring a zone of protoplasm. By indirect division the protosperma- toblasts give rise to deutospermatoblasts, and these to tritospermato- blasts. There are thus two successive mitoses. The head of the spermatozoid and its cap arise from the nucleus, which is differentiated in two directions. The middle part and caudal filament of the spermatozoid arise from the reticulate protoplasm of the tritospermatoblast, but there is in this some “ nuclein-dust,” and at the posterior end of the middle part there is a special “ caudal granule.” There is, of course, in this long memoir, much more than we have been able to summarise ; we have merely noted some of the essential points. * Arch. f. Mikr. Anat., 1. (1897) pp. 110-41 (2 pis.), f Mem. Acad. Montpellier, ii. (1896) pp. 53-238 (9 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 355 A Two-headed Tadpole.* * * § — Mile. M. Loyez describes a tadpole of Itana temjporaria hatched with two heads. These were at first equal and symmetrical, and each bore on its outer side the usual external gills. When the external gills were replaced by the internal set, only one spiracle was formed — to the left side. Very soon the left head began to gain the preponderance. There were four adhesive organs, but the tadpole was never seen to fix itself. It swam well enough, and lived for three weeks. It ate by its left mouth only, at least after the inequality began to be apparent. Its size at death was less than that of the others of the same brood. Blood-formation in the Lamprey.j — Dr. E. Giglio-Tos finds that the hsematopoetic organ of the larval lamprey is the so-called spiral valve of the intestinal wall. The parenchyma of this fold includes three kinds of cells : — (a) the mother-cells, which give rise to (b) hacmocytogenous cells, from which are derived (c) the elements of the blood, the erytliro- blasts and the leucoblasts. Thus the red and white cells have in this case a common origin. Mitosis is the mode of division of all the elements as long as they are included in the stroma of the valve ; the erythroblasts do not contain haemoglobin in their early stages when they are within the stroma of the valve ; the pigment begins to be produced when they reach the plasma of the blood. Development of Dental Enamel.J — Dr. R. R. Andrews gives an account of his researches on the development of dental enamel and a criticism of the results reached by Dr. J. L. Williams.§ In the con- clusion of his paper he expresses his belief that the formation of the enamel is in a sense a secreting process, though he does not believe that secreting papillae have been found in the stratum intermedium in all cases. This requires further investigation. There are two distinct products of the enamel-forming layers. One of these products, from which the enamel-rods themselves are built, is formed in the amelo- blasts, but not by nuclear formation. In the formed enamel-rod the globular bodies are nearly or quite melted into one another at their extremities. As the globular bodies pass from the ameloblasts, they are placed in a network of what appear to be epithelial fibres, which pass within, between, and across the globular masses. Around the scaffolding thus formed the protoplasmic exudate flows, thus supplying the cement sub- stance. Calcification then takes place, and enamel is formed. Mesoderm of the Anterior Region of the Head in the Duck.|| — Prof. H. Rex has made a contribution to this difficult subject. It is not easy to make a summary intelligible without the author’s figures, but the main — though tentative — result is as follows. The Anlagen of the paired pre-mandibular head-cavities (and the canal connecting them) are formed as lateral outgrowths from the degenerate and solidified apical part of the anterior region of the gut. The hollowing out of these rudiments * Bull. Soc. Zool. France, xxii. (1897) pp. 146-8 (4 figs.). f Atti E. Acc. Torino, xxxii. (1897) pp. 362-76 (1 pi.). X Internal. Dental Journal, April 1897, 20 pp., 12 figs. § Cf. this Journal, ante, p. 261. l| Arch. f. Mikr. Anat., 1. (1897) pp. 71-110 (Fpl. and 12 figs.). 356 SUMMARY OF CURRENT RESEARCHES RELATING TO is effected only after the notochord-rudiment associated with the above- mentioned Scheitelrest has been differentiated, and is probably to be regarded as the reappearance of the cavity which originally traversed the Scheitelrest, Development of Excretory Organs in Bdellostoma.* * * § — Mr. G. C. Price was fortunate enough to secure a few embryos of Bdellostoma stouti Lockington. The “ mesonephros ” forms, as is known, the functional excretory organ of the adult, and has 26-81 tubules opening into the relatively large segmental duct ; the part called the jmonephros lies on each side in the pericardial cavity, but in the adult the lumen of its central duct has lost continuity with the lumen of the segmental duct. As in other Vertebrates, the rudiments of the pronephric segmental tubes grow into the rudiment of the segmental duct, and the lumen of the duct is formed in continuity with the lumina of the tubules ; in Bdellostoma , however, this is true not only of the pronephric part, but of the entire system, which is therefore primitive in a much more funda- mental sense than has hitherto been supposed. The author finds in the development and structure of Bdellostoma strong evidence in favour of Biickert’s theory that primitively the excretory system consisted of seg- mental tubules, wrhich opened independently of one another along the side of the body, and that the segmental duct has been formed from these tubules. Further Researches on Metamorphosis of Mursenoids.f — Prof. B. Grassi and Dr. S. Calandruccio are now able to say that they know the larval and semi-larval forms of all the Mediterranean Mursenoids ex- cept the very rare Cldopsis bicolor and the occasional Mursenesox savanna . They have followed the metamorphosis of Leptocephalus brevirosiris into adults, and note that the Leptocephalus stage of Myrus vulgaris is very like that of Ophichthys hispanus (syn. 0. remicaudus), and that the “ Tiluri ” are probably referable to Serrivomer. Development of Eels.J — Prof. G. B. Grassi and Dr. S. Calandruccio have a note on two transitions between Leptoceplialus brevirostris and the young eel. The one had the dental teeth still intact; the other had lost them, but had not acquired the final set. Development of Hypochorda and Ligamentum longitudinale ven- trale in Teleostei.§ — Dr. K. Franz corroborates, in reference to trout and salmon, what other investigators have stated, that the hypochorda develops from the endoderm. It separates from a ridge springing from the dorsal wall of the gut. The separation is associated with the for- mation of segmentally arranged bridges, similar to those which Stolir has described in the frog. No lumen is ever demonstrable in the hypo- chorda. The ligamentum longitudinale ventrale arises from the cells of the axial mesoderm without the elements of the hypochorda taking any share in its formation. The hypochorda disappears (more rapidly in the salmon than in the trout) without contributing to any organ. * Zool. Jahrb. (Abtli. Anat.), x. (1897) pp. 205-26 (2 pis.), f Atti R. Acad. Lincei (Rend.), vi. (1897) p. 43. i Tom. cit., pp. 239-40 (2 figs.). § Morph. Jalirb., xxv. (1897) pp. 143-55 (1 pi. and 2 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 357 Morphological Nature of the Hypochorda.* — Prof. H. Klaatsch has studied this enigmatical structure in embryos of Torpedo and Pristiurus, and, comparing these with AmpMoxus , comes to the conclusion that the hypochorda of Craniota is a rudiment of the epibranchial groove, which is functional in the lancelet. Both have an endodermic origin on the dorsal wall of the gut beneath the notochord and between the paired aortge. The occurrence of a hypoehordal groove in development is also noteworthy. In the adult lancelet the organ is restricted to the pharyngeal region; in young forms it extends further back. In higher forms the rudiment is extended far back over the gut ; but this is regarded as a secondary character. There is no warrant for deriving the hypochorda from meta- rneric dorsal diverticula of the gut. As to its degeneration from a functional groove to a mere band in part elastic, the modification of the respiratory pharynx may have something to do with it ; and it should also be noticed that its reduction makes the development of an unpaired aorta possible. Gastrula of Amphioxus.f — Prof. H. Klaatsch has studied this stage, especially in relation to the concrescence theory. The main result is that the blastopore of the lower Chordata is not closed by the concres- cence of lateral parts, that there is as little of a gastrula-raphe in AmpMoxus as in the higher Vertebrates. What occurs is a gradual narrowing of the blastopore, wherein the “ instreaming ” of cell-material plays its part, as Kopsch has shown for Amphibia. Skeletal Cartilage of Outer Ear in Monotremes.f — Prof. Gr. Ruge has made an interesting discovery in connection with this. The carti- laginous skeleton of the external ear in Echidna is closely associated with the hyoid arch. In Ornithorhynchus the condition is confirmatory, though more primitive. Thus the hyoid arch, before forming the rudi- ment of the stapes by the separation of a dorsal portion, manifests its formative activity in giving origin to the cartilaginous external ear in the Promammalia. Development of Gymnophiona.§ — Dr. A. Brauer has studied the ■development of Rypogeophis rostratus and R. alternans from the Sey- chelles. The segmentation, unlike that of other amphibian types, is meroblastic. One side of the egg showed several layers of blasto- meres ; the other parts showed nuclei with cell boundaries visible peri- pherally ; these nuclei are derived from blastomeres which wander into the yolk. A segmentation cavity was represented merely by gaps between the deeper cells. In the next stage, in the laid eggs, some of the blastomeres form a superficial epithelial layer, while the others are scattered in the enlarged segmentation cavity. The former (the f‘ animal ” cells) arrange them- selves more regularly, and assume a cylindrical form at the future pos- terior end of the embryo. At the posterior margin a broad transverse groove is formed, and there the animal cells are turned downwards and forwards. The lower “ animal layer ” thus formed grows forwards, and * Morph. Jalirb., xxv. (1897) pp. 156-169 (1 pi.). f Tom. cit., pp. 224-43 (1 pi. and 4 figs.). % Tom. cit., pp. 202-23 (6 figs.). § Zool. Jahrb. (Abtli. Anat.), x. (1897) pp. 389-472 (4 pis. and 26 figs.) 358 SUMMARY OF CURRENT RESEARCHES RELATING TO a cleft appears between it and tlie yolk. At this stage there are there- fore two cavities, the anterior segmentation-cavity, and the quite distinct posterior cavity formed as above, and opening at the blastopore. The two come together by a rupture of the separating partition, and an archenteron is formed. The roof of the archenteron usually gives clear evidence of its twofold origin in the different structure of its two sets of cells. In fact, the anterior and posterior regions of the roof do not lose their distinctness of character. The anterior (vegetative) layer grows backwards from the line of contact, insinuating itself beneath the posterior layer, and forming the definitive epithelium of the gut. Before the beginning of this undergrowth, the margin of inturning shows a posterior curvature of its edges, so that an anterior blastopore- lip and two lateral walls are formed. A posterior lip is formed after the complete incurving and coalescence of the two outermost ends of the margin of inturning. Bound the whole of the blastopore margin the ectoderm passes into the mesoderm ; the latter forms a unified rudiment, which (before the above-described undergrowth of the endoderm) con- stitutes part of the roof of the archenteron. From this region, as the endoderm grows under, the rudiments of the notochord and the lateral, plates are formed. At the same time the medullary plate, groove, and canal appear successively. The closure of the blastopore takes place from in front backwards ; by the closure of the anterior part the external communication of the neurenteric canal is shut off ; the internal com- munication with the archenteron remains open for a considerable time \ the most posterior part of the blastopore becomes the anus directly. Present Position of Darwinism.* — Herr G. Wolff has under this title published a lecture, which is almost wholly concerned with a criti- cism of Weismann’s £Neue Gedanken zur Vererbungsfrage,’ an emphatic, compliment to the Freiburg professor, with whose views the lecturer finds himself much at variance. After emphasising the fact that Dar- winism postulates as data quantitative , rather than qualitative variations, Wolff seeks to show that Weismann’s doctrine of Panmixia is inconsis- tent with the Darwinian postulate, since Panmixia cannot be an effective factor except in regard to qualitative variations. It appears to us, how- ever, that a way out of this apparent dilemma has been already indi- cated by several writers on Panmixia, and by one at least — the late Mr. Bomanes. Herr Wolff proceeds to a criticism of the Panmixia idea, resting his argument very largely on the alleged fact that the ontogeny of dwindling structures points not to weakened development of the rudiments, as the doctrine of Panmixia might lead us to expect, but rather to a retrogres- sive metamorphosis. We must confess our inability to see any obvious difficulty ; and as to the case he selects — the occurrence of rudiments of teeth in modern birds— we think any authentic cases of this are far to seek. In support of Panmixia, Weismann has made use of the conclusion that unfavourable variations are more frequent than favourable variations ; but Wolff points out that there is no reason to believe that this is true of purely quantitative variations, such as Darwinism postulates. To avoid this difficulty Weismann has restricted the conclusion as to the * ‘ Der gegenwartige Stand des Darwinismus,’ Leipzig, 8vo, 1896, 30 pp^. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 35& greater frequency of unfavourable variations to quantitative variations among the parts of an organ, and lias committed himself to the sen- tence that “ an organ at the height of adaptation cannot vary in the direction ‘ better/ for every independent deviation of its parts must have the import of 4 worse.’ ” But this seems to Wolff to be sawing at the branch which supports the whole Darwinian theory of pro- gressive evolution. What applies to the disappearance of an organ must also apply to its establishment ; Weismann postulates for both no longer a fortuitous crop of variations, but a definite variation-tendency towards plus when an adaptive character is being evolved, towards minus when it is disappearing. But even this concession may, according to Weismann, be made to consist with Darwinism ; he tries to effect this by an ingenious combina- tion of his Germ-plasm theory with Roux’s theory of the struggle of Parts. Of these two theories Wolff then gives a short account. The main idea of germinal selection is that the determinants, like other parts of the organism, are subject to struggle and intra-selection, in the course of which the stronger become stronger (in assimilative power, &c.), and the weaker become weaker, so that an internal tendency is established which emphasises lines of variation already started and sanctioned by the ordinary selection of individuals. To this Wolff answers as follows : — (1) The theory leaves the be- ginnings of the “ adaptive variation-tendency ” unexplained, thus resem- bling Darwinism in general, the fundamental error of which is that it works only with continuations, not with beginnings. But this is an old story. (2) Supposing that a smaller determinant corresponds to a smaller organ, does it follow that the determinant is weaker in assimilative power ? Smallness and atrophy cannot be identified. If smaller organs arise from determinants which have been weakened in their assimilative power, then, according to Weismann, this assimilative power must con- tinually decrease. But how then can we understand that a small organ persists at all, and may in certain cases even increase again ? Moreover, by what conceivable process — functioning, trophic stimulus, &c. — can the assimilative power of the primarily stronger determinants be further increased ? (3) Finally, Wolff asks what are the real competitors or combatants in the alleged process of germinal selection. Are they the component parts of the germ-plasm ? But these stand in a quite different relation to one another from that occupied by individual organisms in nature, or even by the parts of the body. The factor of “ over-production ” is inap- plicable to the germ-plasm, in which the essential parts of the future organism are represented only once. The author ends by expressing his conviction that the attempt to find a “ mechanical ” explanation of adaptive variation has proved a failure. That may be ; but we miss in this lecture any indication of how the author himself proposes to meet the acknowledged difficulties of the evolution-problem. Correlated Variation.* — Messrs. C. B. Davenport and C. Bullard have studied the variations in the Mullerian glands that are found on. * Proc. Amer. Acad., xxxii. (1896) pp. 87-97. 360 SUMMARY OF CURRENT RESEARCHES RELATING TO the wrist of the fore-legs of swine. These glands occur, when there are several of them, in a linear series, the number of which is variable. Reduction in number takes place generally from the distal end, rarely in the middle of the series. When the number is large, some of them occur outside the main row, either in a row parallel with the main one, or 'at right angles to it. The highest total number observed in one leg is 10, never more than 9 in a row. The total number of swine examined was 4000, 2000 of each sex, 8000 fore-legs. The index of variability is the average departure in the number of glands of any set of legs from the mean number of that set. Galton’s method of finding the index of correlation was used. Results. The average number of glands is tolerably but not strik- ingly close on the two fore-legs and in the two sexes. The glands are nearly 1 per cent, more abundant in the male than in the female. The variants are distributed in close accord with the probability-curve. The variability in the two legs is very similar, especially in the male. The 'males are 2*5 per cent, more variable than the females. The glands are 0*8 per cent, more variable on the left side than on the right side. The relative variability of the same leg in the different sexes is about 1 • 6 per cent, greater than that of the two legs in the same sex. The degree of correlation in the variability of the right and left legs is about 0 • 777. b. Histology. Blood-Vessels in Epithelium.* — Prof. F. Maurer found on examin- ing the buccal mucous membrane of Amphibians (frog, newt, &c.), that the capillaries do not end in the sub-epithelial layer, but pass between the cells of the basal layer, and sometimes (in Anura) even through the middle layer, to the basal surface of the superficial ciliated cells. In the region of the jaw-margin there is neither sub-epithelial nor intra-epithelial capillary plexus. The facts have a threefold interest. (1) They complicate our histological conception of epithelium. (2) To the comparative morpho- logist the intra-epithelial vascular plexus above described is suggestive, since respiratory organs in Vertebrates are associated with the anterior part of the gut. (3) Maurer believes that the intra-epithelial plexus is primarily concerned with the nutrition of the several layers of the epithelium, but that it may come to have secondarily a respiratory significance, e.g. in the lungless Amphibians studied by Wilder, Camerano, and Lonnberg. Uterine Mucosa' of Bat during Gestation, t — M. Pierre Nolf ends his memoir on this subject with a comparative survey. (1) In Insecti- vores, Carnivores, Rodents, and Bats, the essential phenomenon observed in the uterine mucosa during gestation is the destruction of a more or less important part — a destruction often preceded by a phase of hyper- trophy. (2) There is a rapid destruction of the lining epithelium of the uterus, which may be preceded by a very short phase of prolifera- tion. (3) In Carnivores, the modifications induced by gestation affect especially the superficial part of the glandular tubes ; the mucosa * Morph. Jahrb., xxv. (1897) pp. 190-201 (1 pi.). f Arch. Biol., xiv. (1896) pp. 561-693 (7 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 361 remaining, as Duval lias sliown, normal through the gestation. (4) In Insectivores the destruction of the mucosa is almost complete during gestation, and the reaction varies with the genera, being sometimes mostly epithelial, sometimes mostly dermic. (5) In Rodents there is a rapid disappearance of the glands (after a short phase of hypertrophy in the rabbit), and the modifications of the dermis are most prominent. Here again the destruction extends into the deep dermic layers (Duval). (6) In bats ( Vespertilio murinus), the hypertrophy affects the dermis, and the necrosis penetrates through the whole thickness of the dermis, except to some elements intimately applied to the musculature. (7) In the bat there is a complication. A limited portion of the dermis, in immediate contact with the external placental* surface, differentiates from the deep layers, and undergoes independent modification. It forms a vascularised para-placentar layer. (8) When there is a not- able difference between the volume of the fertilised ovum and the uterine cavity, and when the swelling of the mucosa is strongly marked, the ovum is surrounded in a reflected decidua. Cell-Bridges in TJnstriped Muscles.* — Dr. H. Triepel notes that many investigators have described intercellular bridges in the unstriped muscle of Mammals. He has added to the list of cases by finding them very distinctly in the longitudinal intestinal musculature of the ox. He fixed his material in 4 per cent, formol solution, and stained with haema- toxylin and neutral orcein. The appearance of bridges is not due to longitudinal ridges, for there are none ; but a longitudinal striation nr fibrillation does occur in the cells. He observed spiral ridges with two or three turns on a cell, but these are contraction phenomena. The intercellular bridges are not to be confused with marginal irregularities which ^correspond to the spiral ridges, nor with certain long threads, which are probably due to insinuated connective tissue elements. Comparative Histology of the Liver.f — Herr J. F. Holm has compared Myxine , Ammocoetes , Petromyzon, and Scyllium , as regards the structure of the liver. As long as the liver is directly secretory, it has the character of a tubular gland, as is plainly seen in Myxine. In the larval lamprey the same condition occurs, but it is lost as the secretory function ceases. In the dog-fish there does not seem at first sight much ;hint of a glandular character, but this comes out when embryonic stages are observed. The primitive state of the liver was doubtless that of a tubular gland. Permeability of the Skin.i — Margherita Traube-Mengarini has experimented on the osmotic permeability of the skin. There can be but little, else fresh-water animals would swell up and marine animals would shrink. Only in parasites which live in a solution of constant esmotic pressure is the skin markedly permeable. Thus a living Opalina may be readily penetrated by eosin, if the medium is other- wise suitable. In Metazoa, the intestinal tract alone shows osmosis. Thus, if frogs swallow the coloured water in which they are placed, they are gradually coloured through and through ; but if the mouth * Anat. Anzeig., xiii. (1897) pp. 501-3. t Zool. Jahrb. (Abth. Anat.), x. (1897) pp. 277-86 (2 pis.). % Rend. Acc. Lincei, v. (1S96). See Biol. Centralbl., xvii. (1897) pp. 29-30. 362 SUMMARY OF CURRENT RESEARCHES RELATING TO remains shut, none of the colouring matter passes below the outermost epithelial layer. In special cases, e.g. frogs in 5 per cent, salt solution or patients in mineral baths, water may diffuse outwards through the skin ; but this is abnormal. Structure and Development of Cartilage in Cyclostomes.* — Herr J. Schaffer begins by discussing the soft or “ blue ” cartilage as seen, for instance, in the branchial skeleton of Ammocoetes. Its ground- substance is a simple honeycomb or alveolar system separating the cells; and these component cells or chondroblasts are able not only to secrete cartilaginous substance around themselves, but also to assimi- late the adjacent tissue, and to modify it into chondrogenic substance. In Ammocoetes , the primary cement-substance and the capsular substance produced by the cells are quite indistinguishable. In the soft or grey cartilage of Myxine, however, the intercellular septa show, in some places at least, a distinction between the primary cement-substance and the secondarily deposited capsular substance. Schaffer places this kind of cartilage between the branchial and the cranial cartilage of the larval lamprey. In the hard or “ yellow ” cartilage of Myxine , Schaffer interprets the capsular substance which fills the alveoli of the cement-substance, as the analogue of a cell- chamber, since acid anilin stains demonstrate an internal well-defined zone, the capsule proper, and an external unstained layer. By regressive changes, however, the capsules may be changed into ground-substance. The variety of cartilage, even in the same animal, is probably due to the diverse development of the components, — primary cement-substance, capsule-proper, and cell-chamber. As to the development, the author emphasises the assimilatory function of the chondroblasts. In the metamorphosis of the lamprey, the new cartilage is not formed by direct change — metaplasis — of the larval tissue, but there is new formation or immigration of chondro- blasts which form the new cartilage. Schaffer compares his results in detail with those of Studnicka who has recently worked at the same subject. Nerve-Endings in Tactile Hairs of Mammals. f — Herr E. Botezat has studied the innervation of the tactile hairs in mouse, rat, cat, pig, and other forms, chiefly by means of the methylen-blue method. His most important new results are the following : — (1) The nerve-fibres of the deep plexus of the inner hair follicle penetrate the vitreous or homogeneous membrane (between the outer root-sheath and the internal follicle), and form tactile menisci internal to it. These menisci occur not only in the lower part of the root-sheath swelling, but also in the deeper parts of the root-sheath which reach down to the papilla and form no swelling. (2) The real endings of the sensory hair nerves are the terminal fibres into which the sensory menisci pass. These project into the interior of the root-sheath and end freely between its cells. (3) From the annular plexus (of epidermic and follicular nerves)* which occurs in several animals, processes of the axis-cylinders pene- trate the vitreous membrane and form free endings internal to it. * Arch. f. Mikr. Anat., 1. (1897) pp. 170-88. f Tom. cit., pp. 142-69 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 363 Tlius the external root-sheath of the tactile hairs is seen to be much more richly innervated than has been hitherto recognised, and the terminal sensory apparatus expands within the entire vitreous membrane. Structure of the Neuroglia of the White Matter of the Spinal Cord.* * * § — Herr Fr. Reinke concludes that the framework of the supporting substance or neuroglia in the white matter of the adult human spinal eord consists of both cells and fibrils. A. The cells have numerous partially branched protoplasmic pro- cesses, which run in part transversely and obliquely, but for the most part vertically, parallel with the nerves. They are well shown by Golgi’s method. B. The fibrils are morphologically, physically, and chemically, quite different from the cells and their protoplasmic processes. They are, however, formed from the protoplasm, lie in and partly on it, and in adult man run in an essentially opposite direction to the protoplasmic processes. In great part these fibrils, as to the length of which nothing is known, have become quite free from the cell-body. Similarly there are cells which are in connection with only a few fibrils or with none. The fibrils are of very unequal thickness and perhaps without ana- stomoses. They are beautifully shown by Weigert’s method. Lenhossek with Golgi’s method, and Weigert with his own staining, both reached accurate results ; all that was wanting was a combination. This was effected by Kolliker, whom the author corroborates. Lingual Glands of Vipers.f — Dr. 0. Bisogni describes a superior lingual gland lying in the tongue-sheath of Vipera JEtedii , V. chersea , V. Ammodytes, V. Asjpis ocellata, and V. Asjpis maculata. It is probably of more general occurrence. Its function is to assist the inferior lingual gland common to all Ophidians. The histological structure resembles that of ordinary salivary glands. Secretory tubes, lined by cylindrical glandular epithelium, are united by abundant connective tissue. The glandular cells have their nuclei at their base, and appear granular when in secretory activity, homogeneous when in repose. In a second paper, J which is somewhat beyond the scope of this Journal, Bisogni calls attention to the exact anatomical correspondence in non-venomous snakes between the group of sub-lingual glands and the jugular plates which form the cutaneous covering of the lower jaw. Nuclear Degeneration and Renewals — L. Cuenot directs attention to the degeneration of the macronucleus in the Gregarine Biplocystis. It remains intact during the enormous increase of the cell, from 8 to 1300 /x, when for about four months reserves are accumulated. There- after, presumably as the result of its share in metabolism, it is as it were used up and incapable of division. Degeneration follows, and the micro- nucleus enters upon its distinctly reproductive role. Similar phenomena are known in Infusorians, in Thalassicola, and in Coccidia. Cuenot compares them with processes which occur or, as he says, ought to occur * Arch. f. Mikr. Anat., 1. (1897) pp. 1-14 (1 pi.). ; + Anat. Anzeig., xiii. (1897) pp. 490-94 (3 figs.). ' % Tom. cit., pp. 495-8 (3 figs.). § Comptes Rendus, cxxv. (1897) pp. 190-3. 364: SUMMARY OF CURRENT RESEARCHES RELATING TO in the eggs of Metazoa. Thus the egg of Salamandra maculosa accumu- lates reserves for four years, and grows from 28 to 3500 /ul, and is, he says, in the same sort of state as the full-grown Gregarine. It may be that the rejection of used-up material is effected by the first polar body ; but apart from this it is noted that Haecker has described some possibly analogous process in JEquorea, and Wheeler in Myzostoma. The author ventures the suggestion that “l’epuration nucleaire” is of general occurrence. c. General. Comparative Anatomy of Vertebrates.* — Prof. W. N. Parker has edited a second English edition of this well-known text-book by Prof. R. Wiedersheim. It has been almost entirely re-written, so as to incorporate the new material of the third German edition without too great increase of size. Continually, however, as the history of this book shows, the “ Grundriss” tends to grow into the “ Lehrbuch.” The excellencies of the book are well known ; it is enough to say that, good as it was before, it is better now. Anticipation of Modern Views on Evolution.! — Prof. E. B. Poulton calls attention to the importance of the evolutionary views of James Cowles Prichard, the anthropologist. In the second edition of his ‘ Researches into the Physical History of Mankind ’ (1826), he argued forcibly in favour of organic evolution ; he recognised the operation of artificial and natural selection ; and he not only drew a clear distinc- tion between acquired and congenital characters, but sought to show that the former were not transmitted. He was not rigidly consistent, and in after years his convictions seemed to have weakened, but some of his sentences might have been written by Darwin and others by Weismann. We shall quote two: — “It appears to be a general fact, that all connate varieties of structure, or peculiarities which are congenital, or which form a part of the natural constitution impressed on an individual from his birth, or rather from the commencement of his organisation, whether they happen to descend to him from a long inheritance, or to spring up for the first time in his own person — for this is perhaps altogether in- different— are apt to reappear in his offspring.” ... “On the other hand, changes produced by external causes in the appearance or consti- tution of the individual are temporary, and, in general, acquired characters are transient ; they terminate with the individual, and have no influence on the progeny.” We may note that Prichard’s position on this question is referred to very explicitly by Lucas in his great work on Heredity (1847-50). So-called Accessory Parts of the Skeleton.! — Dr. G. Thilenius begins an interesting discussion by criticising Emery’s classification of “ accessory ” skeletal parts, i.e. novel additions to the primitive skeletal system. Emery’s first division includes parts which are only found in ‘ Elements of the Comparative Anatomy of Vertebrates,’ adapted from the German of Dr. Robert Wiedersheim by W. N. Parker. 2nd edition, founded on the third German edition. London and New York, 8vo, 1897, xvi. and 488 pp., 333 figs. f Science Progress, i. (1897) pp. 278-96. % Anat. Anzeig., xiii. (1897) pp. 483-90. ZOOLOGY AND BOTANY* MICROSCOPY* ETC. 365 particular genera or families, to which. Thilenius objects that this pre- supposes a complete knowledge of comparative anatomy. Thus, a few years ago the radiale externum would have been ranked in this division, but no one would now admit this. Emery’s second division includes parts which are typical for Mammals, but have been secondarily added, for instance to the original chiridium, as is shown by their absence in other Vertebrates. He gives the metacarpo-phalangeal sesamoids as an example ; but Thilenius notes that he has suggested the presence of sesamoids in the anomodont Keirognatlius cordylus, and that Nassonov has described hyaline cartilage preformations of metacarpo-phalangeal sesamoids in the ostrich. Emery’s third category includes accessory parts falsely so-called ; and to this Thilenius has no objection, except that he questions whether it does not include all the cases. An appeal has been made in this connection to the supposed ontogenic recapitulation of phylogeny, but the author places little confidence in this. The phyletic time-succession is not observed ; the Vertebrate central nervous system appears in the gastrula stage, the heart is present and functioning before there are capillaries, the wisdom-tooth is surely not phyletically younger than the others. In fact, the ontogenic suc- cession is influenced by the physiological importance of the parts, unim- portant parts being slowed, important parts being hastened. Therefore one «cannot determine phyletic age by time of ontogenic appearance. At the same time, ontogeny is of much importance in showing the process by which the adult state is reached, by revealing parts which are absent or rudimentary in the full-grown form, and by exhibiting structural conditions of ancient date, as in the pentadactyl Anlage of the bird hand. “ Accessory,” like other parts of the skeleton, may be represented in the embryo by preformations in connective tissue, e.g. the Wormian bones of the skull, or by preformations in hyaline cartilage, e.g. the metacarpo-phalangeal sesamoids. Neither here nor in histological dis- tinctions can the conception of strictly novel accessory parts find at present any secure basis. Venoms of Toad and Salamander.* — Dr. E. T. Hewlett gives an account of recent researches and of his own investigations into the cutaneous secretions of the toad and salamander. Both animals secrete, from special skin-glands, an intensely bitter venom, differing entirely from snake-poison in that it is alkaloidal, not proteid. The venom of both, if subcutaneously injected, is fatal to birds, dogs, and guinea-pigs ; administered by the mouth, that of the toad produces only vomiting, that of the salamander is toxic only in large quantities. Phrynin, or bufidine, the active principle of toad-venom, has an action on respiration and cir- culation not unlike that of digitalis; salamandrine is predominantly convulsive in its action, and has no direct effect upon the heart. The venom is fatal to the animal which secretes it only when administered in comparatively large doses ; but an ordinary dose of the venom of the toad or the newt kills the salamander, and an ordinary dose of salaman- drine is fatal to the newt and the toad, though all the secretions have a general similarity in action. * Science Progress, i. (1897) pp. 397-405. 366 SUMMARY OF CURRENT RESEARCHES RELATING TO Japanese Zoology.* — Prof. K. Mitsukuri, in introducing ‘ Annota- tions Zoologicae Japonenses,’ which is referred to in detail in this number of the Journal, takes an interesting retrospect of the progress of zoology in Japan. In the eighth century Japan had its Imperial Uni- versity; in the ninth century the Imperial Library contained 16,790 volumes, some with “ very modern sounding titles ” ; early in the eighteenth century there was a treatise on Natural History, in 1000 parts ; and the naturalist Ono Ranzan, at the beginning of this century, had nearly one thousand pupils. Over 300 Japanese works on Botany existed before 1868, and the Botanic Garden of the Imperial University was established in 1681. The treasury of Western civilisation was first opened by a Dutch key. The visits of Thunberg (1775) and Siebold (1821) had their due effect on natural history studies. A work on the use of the Microscope was published in 1801. With the restoration in 1868 a new period began, and the modern Japanese school of zoology dates from the appointment of Prof. E. S. Morse to the chair of Zoology in Tokyo in 1877. Prof. Whitman introduced modern technical methods. Since 1881 the development of zoology in Japan has been entirely in the hands of Japanese, and a vigorous school has sprung up, as all zoologists are now aware. Natural History of the Sea.f — Mr. George Murray has written an interesting article with this title. It contains some account of pre- £ Challenger ’ work, discusses some of the conclusions and suggestions of the final £ Challenger ’ volumes, and notices some post-£ Challenger * re- searches, e.g. Fischer’s study of Bacteria in the sea, Schiitt’s study of Peridinese, and the evidence which Prof. McIntosh and Mr. George Murray have furnished, that, as “ all flesh is grass,” so all fish appears to be diatom. The article ends with a note on a simple method of con- verting a mail steamer into a Plankton expedition. Life in the Primeval Ocean.J — Mr. C. Morris draws a necessarily speculative picture of the primeval ocean. As its waters ‘‘slowly cooled, and inorganic eliemism declined in activity, organic chemistry probably set in, aided by the solar rays, then perhaps first freely reaching the waters. The material for this new phase of action had been prepared before, and existed abundantly in the water and air. . . . Certainly organic forms appeared in the waters of that period, and conditions favouring their formation must have existed. . . . Seed-forms of organic substance may have first appeared — simple carbon compounds. These would serve as the basis of more complex molecules, and there may have been a long-continued process of de-oxidation and formation of higher carbon and nitrogen compounds, till true organic matter appeared. . . . The conditions favouring the development of organic material were transitory, and no longer exist.” Tunicata. Budding in Ecteinascidia.§ — Dr. G. Lefevre comments upon the absence of parallelism between embryonic and bud-development, which * ‘ Annotation es Zoologicse Japonenses, Auspiciis Societatis Zoologies Tokyo- nensis, seriatim editse,’ i. (1897) Tokyo, pp. i-xi. t Science Progress, i. (1897) pp. 379-96. j Proc. Acad. Nat. Sci. Philad., 1897, pp. 12-17. § Anat. Anzeig., xiii. (1897) pp. 473-83 (6 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 367 many recent researches have made prominent, and which his own study of Ecteinascidia turbinata, one of the Clavelinidte, confirms. The bud- development of this form is very like that of Perophora annectens , though without the peculiar rotation or transverse shifting of the inner vesicle which occurs in the latter. The absence of an epicardium, with which the formation of the pericardium is closely connected, sharply contrasts these two genera with Glavelina. In Ecteinascidia and Perophora annectens the pericardium, dorsal tube, and ganglion (and in the former the gonads also), are all formed, in greater part at least, from cells which wander out from the wall of the inner vesicle into the rudiments. The primitive vesicle is the all-important part of the bud-rudiment, providing material for all the internal structures, for the ectoderm has no active role except as regards the test. Whether derived from an ectodermic or an endodermic larval structure, it gives rise to all the organs derived in embryonic development from the two primary germinal layers, and in some cases it also furnishes cells to the blood, as in the two forms last-mentioned. But although it is undifferentiated, like a blastula, it is mapped out into areas which form particular structures ; and it is possible to make a series showing varying degrees of this differentiation. Thus, at the lowest end stands Perophora viridis; a step higher we find Ecteinascidia and Peropliora annectens ; a still higher grade is illustrated by Botryllus and many others. Compound Larva of a Synascidian.*— M. Maurice Caullery has studied Diplosomoides Lacazii Giard, a Synascidian of the family Didem- niae, which, as Lahille has observed, begins to bud during the develop- ment of the oozo'id. According to Lahille, the hatched larva is already a colony of three individuals — the oozoid and two blastozoids. Accord- ing to Caullery, the hatched larva includes (a) the oozoid, typical, except that the terminal part of the digestive tube is atrophied ; (b) a typical abdominal bud ; and (c) two complementary thoracic half-buds. Perhaps it is most correct to say that there are two individuals— the oozoid and diverse parts of a blastozoid. It has a twofold interest, (1) in the precocity of the budding, and (2) in the separation of the two halves of the thoracic bud. The latter peculiarity may be explained by the presence of an abundant vitellus ; it may be an illustration of the mechanical influence of the vitellus on the processes of morphogenesis. Follicle-Cells in Salpa^ — Mr. M. M. Metcalf discusses these cells, which have been the subject of such discrepant interpretation. Salensky believed that the fertilised ovum merely served as food for its unfertilised sister-cells — the follicle-cells — which he regarded as truly formative. Brooks believed that the embryo was blocked out in follicle-cells, which were afterwards replaced by blastomeres. Heider and Korotneff have continued the inquiry. What Metcalf has shown may be very briefly stated. He finds that the disputed bodies within the blastomeres have a distinctly nuclear character, and he interprets them, with Brooks, but against Heider and Korotneff, as the ingested nuclei of the follicle-cells. Heider regarded the bodies as nucleated cells, Korotneff found no trace of a nucleus within them, Metcalf says they are nuclei in process of digestion. * Comptes Rendus, cxxv. (1897) pp. 54-7. f Zool. Anzeig., xx. (1897) pp. 210-17(1 fig.). 1897 2 d 368 SUMMARY OF CURRENT RESEARCHES RELATING TO INVERTEBRATA. Microfauna of Samoa.* — Dr. A. Kramer gives a picturesque de- scription of a wood-lake in Samoa, enclosed by a crater-wall and encircled by palms. It abounds in vegetable debris, but contained few animals. He collected two new species of Cyclops , and another Copepod ; Dapli- nella, Macrothrix , Alona , and other Cladocera ; a small Nematode, and some insect larvae. The point of his note is rather to emphasise the im- portance of studying the freshwater Plankton in these regions, for it seems to be one of the last things that even the naturalist traveller thinks of doing. Mollusca. Skill-Glands of Molluscs.f — Dr. J. Thiele discusses the minute structure and homologies of the skin-glands in a large number of Molluscs. Thus he compares Haliotis and Area as follows : — Haliotis. Area. Anterior foot-gland. Lip-gland. Sole-gland. Peripheral goblet-cells. Sole. Anterior foot-gland. Mucus gland in foot-groove. Byssus-gland. Posterior mucus-gland. Peripheral mucus-glands. Foot-groove and Byssus-cavity. All the skin-glands have this character in common, that they are composed of glandular cells and supporting cells. The latter constitute a meshwork in which the former are wholly or partly imbedded. The author proposes to use this character as a means of distinguishing the skin-glands from those of the mesoderm and endoderm, and gives a number of examples corroborating the distinction. Molluscan Fauna of Freshwater Lakes in Central Celebes.}: — Plerren P. and F. Sarasin direct attention to the remarkable molluscs which live in the large and deep inland lakes of Celebes. The forms they were able to capture point to the existence of a fauna perhaps as interesting as that of the Lake of Baikal. The authors begin with a new Gasteropod — Miratesta celebensis, for the reception of which it seems necessary to establish not only a new genus, but a new family (Mirates- tidse). The structure, which is briefly described, shows a combination of characters distinctive of various families. The animal is nearest the freshwater Pulmonates, especially the Limnseidse, as is suggested by the Planorbis- like structure of the radula, the nervous system without chiastoneury, the hermaphroditism, and the absence of an operculum. But any very close affinity is impossible, as is shown by the large gills, the very peculiar pouched feelers, and the structure of the shell. Dis- tant relations may perhaps be found in the so-called Thalassophilac ( Amphibola and Siplionaria'). In any case, the family is phylogenet- ic ally old, near the base of the freshwater Pulmonates. * Zool. Anzeig., xx. 1897, pp. 135-6. t Zeitschr. f. wiss. Zoo]., lxii. (1897) pp. 632-70 (2 ids.). X Zool. Anzeig., xx. (1897) pp. 241-5 (2 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 369 a. Cephalopoda. Indian Cephalopods.* — Mr. E. S. Goodrich reports on a collection of cuttlefishes received from the Calcutta Museum, and for the most part collected by the ‘ Investigator.’ Eleven new species are described, belonging to the genera Inioteutliis , Sepia, Loliolus , Sepioteuthis, Abralia , Cheiroteuthis, Histiopsis, Taonius , and Octopus. No new genus has been founded, but four genera included are new to the Indian region. y. Gastropoda. New Gastropod in an Antarctic Kolothurian.f — Prof. H. Ludwig has found in two specimens of Chiridota Pisanii, a new Gastropod para- site, which, in its habit and mode of fixation, resembles a form which he previously discovered in Myriotrochus Pinlcii, and which Voigt described under the title Entocolax LudwigiL Whether the new form is really related to Entocolax or to the more familiar Entoconcha remains to be seen. Nervous System of Molluscs.]: — Dr. J. Gilchrist has studied this by the methylen-blue method. He injected a nearly saturated solution into the living animal by the foot or by the blood system. The tentacles baffled the method until the device of first injecting cocain (5 per cent, in sea-water) was discovered. Good results w’ere obtained with Aplysia, but not with Doris , Patella, or Lamellibranclis. Each case seems to require some special treatment. The ganglia of Aplysia showed (1) typical motor-cells, each with a long axis-process leading away into the nerve, and other processes which break up into fine branches in the ganglia; and (2) cells, the smaller processes of which break up in one ganglion, while the main process passes over into another, probably breaking up there. Fibres passing into the ganglia were seen to break up into branches. An investigation of peripheral parts showed hints of a hypodermal nerve-plexus. Various attempts have been made to discover the connection between the osphradial epithelium and the underlying ganglion ; Gilchrist has demonstrated the existence of intra- epithelial structures — the peripheral endings of sensory cells, the nucleated bodies of which lie at a greater or less depth under the epithelium, and the lower offshoots of which pene- trate the ganglion. The rhinophore shows an arrangement of ganglionic cells somewhat similar to that of the osphradium. Phenomena of Fertilisation and Maturation in Gastropod Ova.§— Dr. F. M. MacFarland begins by describing the fertilisation phenomena in the Opisthobranch Pleurophyllia calif ornica (Cooper) Bergb. The centrosomes which form the poles of the first segmentation spindle arise exclusively from the spermatozoon ; they retain their independence throughout, though they are not continuously visible. There is no quadrille of the centres. The central spindle in the first cleavage arises by the approximation of two ray-systems, which are at first quite separate, * Trans. Linn, Soc. Zool., vii. (1896) pp. 1-24 (5 pis.). t Zool. Anzeig., xx. (1897) pp. 248-9. X Journ. Linn. Soc. (Zool.), xxvi. (1897) pp. 179-86 (1 pi.). § Zool. Jahrb. (Abth. Anat.), x. (1897) pp. 227-64 (5 pis.). 2 D 2 370 SUMMARY OF CURRENT RESEARCHES RELATING TO and by the fusion of certain groups of their radii. Here the author’s results entirely agree with Driiner’s. Secondly, MacFarland describes the behaviour of the centrosomes in the maturation of the eggs of another Opistliobranch, Diaulula sandie- gensis (Cooper) Bergh. The second directive spindle with its centro- somes (but not including the mantle-fibres) arises by gradual growth and associated change of form from the inner centrosome of the first directive spindle. The daughter centrosomes arise from the division of the mother centrosome, but a residue is left which forms the central spindle. In short, as Heidenhain has said, “ central spindle and centro- somes are in their origin one whole.” The same is probably true in the case of the first polar body, but the difficulties of observation prohibit a certain conclusion. Structure of Apera Burnupi.* — Mr. W. E. Collinge describes the alimentary canal, pedal gland, and reproductive organs of this Natal slug. That Apera has affinities with the Testacellidee admits of little doubt, but there is a wide gap between it and either Testacella or Daudebardia. In the generalised character of its reproductive organs, it resembles in some ways the genus Schizoglossa, but here again there is a wide gap. 5. Lamellibranchiata. Hinge-Teeth in Lamellibranchs.} — M. Felix Bernard discusses the morphology of the hinge-teeth. The Mytilidre furnish a starting pointy they and the other Anisomyaria illustrate the state which Neumayr called dysodont. From the normal dysodont type a regressive and a pro- gressive developmental series may be said to emerge. The former is illustrated by Plicatula and oysters ; the latter begins in Crenella and Aviculidao, becomes pronounced in Arcidae and Carditaceae, and is more and more accelerated in Lucinacete, Cyrenaceae, and other families, which show the division of the primitive plate into cardinal and lateral teeth. Considered mechanically, the evolutionary process is roughly this : — at first, the provinculum was enough to secure the fixity of the hinge ; dysodont teeth prevented dorso-ventral slipping ; the hinge grew,, the fine dentations became insufficient, the primitive plates curved and prevented both horizontal and vertical slipping ; division of labour occurred between the different segments, becoming always more precise in its effect, and precocious in its ontogenetic appearance. The total disappearance of the pro vinculum in the majority of Heterodonts is the natural consequence of this acceleration. Arthropoda. a. Insecta. Castes in Termites.} — A translation (by W. F. H. Blandford) is pub- lished of the second portion of the valuable memoir by Prof. B. Grassi, in collaboration with Dr. A. Sandias, on the constitution and development of Termite societies. The paper embodies the result of a long series of observations on Calotermes and Termes. From his study of these and * Arm. Nat. Hist., xx. (1897) pp. 221-5 (1 pi.). f Comptes Rendus, cxxv. (1897) pp. 48-51. % Quart. Journ. Micr. Sci., xl. (1897) pp. 1-75. ZOOLOGY AND BOTANY, MICBOSCOPY, ETC. 371 from tlie results of other workers. Prof. Grassi has been led to conclude that all the species of Termitids® belong to two main types. These are : — (1) A colony presided over by a king and queen, which have possessed and shed fully developed wings. When orphaned, it is headed by a pair of royal substitutes or neoteinic forms. (2) A colony at the head of which are numerous neoteinic queens, the kings — also neoteinic — being present for short periods only. The colony is not founded by the royal forms which govern it ; the neoteinic forms have been raised by a detached portion of a pre-existing colony, which thus founds a new and independent society. Many fully winged insects emerge every year from the nest of Calo- termes flavicollis and Tevmes lucifugus. A certain number of those belonging to the former species succeed in founding new colonies ; but those of the latter are all irretrievably lost under natural conditions — at least in Sicily. The males and females swarm separately, and con- sanguineous pairing is thereby rendered difficult. The winged Calotermes settle on decayed trees, get rid of their wings, and begin to burrow. The sexes meet and pair, and each pair begins to found a fresh colony. Such pairs have the antennae mutilated, and these organs are never found intact in a royal pair either of Calotermes or Termes. Termites com- municate among themselves chiefly by a jerking convulsion of the whole body. The tibial organ, discovered by Fritz Muller, is tympanic, and probably auditory. Termites appear to hear the sounds produced by the convulsive movements. Members of the same nest recognise each other. The food of Termitidae consists of — (1) Triturated particles of dead or decayed wood. (2) The material disgorged by their fellows, wood-particles mixed with saliva. (3) The excrement of their fellows : this is their favourite food, and they solicit it by caressing the abdomen of another insect with their feet. It is not sufficient to maintain life unless wood is procurable. Thus a colony of soldiers which cannot gnaw wood soon dies of starvation ; but one large larva which is constantly burrowing can keep eight or ten soldiers alive. (4) Dead, moribund, or even healthy but superfluous individuals of the same species. (5) The salivary secretion of their fellows (a transparent alkaline liquid). Occa- sionally they imbibe water, but not habitually. The colony can modify the development of a certain number of in- dividuals, which would normally become perfect insects, by varying the quantity and proportion of their nutriment. It thus obtains workers, soldiers, and neoteinic forms. The neoteinic forms become sexually mature without fully acquiring the perfect instar, and thus preserve the facies of the larva or nymph ; they consist of substitute or complementary kings and queens. These transformations can take place without limita- tion as to age in the individuals selected. The larvae and nymphs administer a large quantity of saliva to individuals destined to become neoteinic. This causes the disappearance of the parasitic Protozoa otherwise always found within the alimentary canal. The importance of this is not clearly understood ; but it is not sufficient in itself to pro- duce neoteinia. Newly born larvae receive nothing but saliva ; those in process of becoming workers or soldiers receive little or none. Termes lucifugus often migrates from one tree to another, carrying eggs and 372 SUMMARY OF CURRENT RESEARCHES RELATING TO young ; but as long as communication with the main colony is kept up, may not provide new queens ; but as soon as this is lost, many substitutes are provided, and thus new colonies arise. In Calotermes , strangers of the same species are readily received into a nest ; and even a royal pair may be received if they are orphaned. Jealousy is most conspicuous among royal forms, but is less marked than among bees. Several sub- stitute pairs are provided to replace the true royal pair ; but only one usually survives the conflict which takes place. The paper also contains a historical survey of earlier works on the same subject, and appendices on the Protozoa parasitic in Termites, and on the Embiidas. Embiidge.* — Prof. B. Grassi, in an appendix to his memoir on Ter- mites, makes a contribution to the study of the Embiidae. He gives a detailed account of the external features of the larva and the adult male and female of Embia solieri , which is widely distributed in Italy, but of which only the larval form has hitherto been known. There is no trace of wings in either sex at any stage. The insects live from November till May in ramifying silken galleries which they construct under stones. From May to July they make their galleries 10-15 cm. under ground, to avoid too great dryness. The spinning of a gallery takes from 12-15 hours, and is accomplished with the fore-legs either alternately or to- gether, with intervals of rest. The silk is extruded as a liquid ; and from its structure and the method in which the insect works, Prof. Grassi concludes that it is secreted in the anterior legs, which have well developed glands. The Embiae become adult about the middle of June, pair at the end of that month, and probably die during summer. The species in question is degenerate in being wingless. This is probably due to the fact that the climate of Europe is not so hot as that of the countries where most species occur. The insects do not acquire wings before summer drought sets in, and there is a precocious maturation of the generative organs (neoteinia). The authors give an account of the internal anatomy, which the trans- lator supplements from his study of Embia uricliii. The systematic posi- tion remains doubtful. They are very remote from Termitidae, and have no more definite affinity with Perlidae ; nor is the much-mooted relation- shop with Psocidae more than problematical. Grassi thinks that they should be ranked among Orthoptera (s. lat.) as a special sub-order parallel with Orthoptera (s. str.). The translator is inclined to assign them a position intermediate between the Thysanura and the Orthoptera Oursoria. Development of Lepisma.j — Dr. P. Heymons has studied the de- velopment of this primitive form (L. saccliarina L.). The eggs are laid by means of a long and extremely narrow ovipositor ; their form is a long oval ; their colour changes from whitish to yellowish-brown ; the shell consists of a delicate colourless exochorion, and a firm resistant endochorion ; the content shows yolk-balls and fat-drops between them ; the segmentation is peripheral. * Quart. Journ. Micr. Soi., xl. (1897) pp. 55-75 (the date of the original paper is 1S88-9). t Zeitschr. f. wiss. Zool., Ixii. (1897) pp. 583-G31 (2 pis. and 3 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 373 Tlie relatively small germinal streak develops ventrally ; the rela- tively extensive extra-embryonic area is covered by very large flat cells (= serosa-cells). In the middle of the embryonic disc a dark spot appears where the mesoderm cells wander into the interior. The very early incurving of the germinal streak into the yoke is noteworthy. It can hardly be doubted that this had to do with the development of the amnion. The amnion-cavity has a persistent amnion-pore, secondarily closed by a chitinous membrane produced by the serosa. As regards the segmentation of the body, the results confirm what has been estab- lished in Orthoptera and Odonata ; indeed, the resemblances between the entire development of Lepisma and that of Orthoptera are very close. At the end of embryonic development, the head acquires a brownish chitinous egg-tooth, which serves to open the shell. The young larva is whitish ; even the eyes are but slightly coloured. It seeks out a daik corner and subsists for some days on its yolk. On the seventh day the first moulting occurs. The differences between the larva and the adult, though relatively trivial, are quite distinct, and are duly enumerated. The author proceeds to a description of the development of par- ticular parts. We can only notice a few points. (1) The styles do not arise until some time after hatching ; they develop from a part of the body which has directly arisen from rudiments of embryonic appendages. (2) The origin of the mesoderm and its derivatives, though in some respects peculiar, bears a strong resemblance to what is known in Orthoptera. (3) The ganglion-cells are formed, as in Orthoptera, from large neuroblasts which appear in the neural ridges on each side of the deep and narrow neural groove. There is at first but a slight development of the longitudinal commissures of the nerve-chain ; even when the young form leaves the egg, the whole ventral cord is a con- tinuous strand. (4) The tracheae are late in developing. Besides the meso- and meta-thorax, the first nine abdominal segments have stigmata, and even the tenth segment has a hint of one. As the adult has only ten (Grassi), the ninth abdominal stigma is probably lost. The appear- ance of stigmata or stigma-rudiments beyond the eighth abdominal segment is a primitive character. (5) The genital cells make their appearance very early. There is no evidence of homology between gonapophyses and appendages. (6) The origin of the mid-gut is quite different from that in Orthoptera. It is formed from the yolk-cells. In two concluding chapters, the author points out particularly (a) the resemblance between the development of Lepisma and that of Orthoptera, and (6) the bearing of his observations on some vexed questions in the comparative morphology of insects. Development of Campodea.* — Dr. H. Uxel continues his pre- liminary account of the development of Campodea staphylinus Westw. The most important results are the following : — (1) On the intercalary (pre-maxillary) segment of the embryo there are appendages which form part of the oral apparatus in the adult, namely the intercalary lobes. (2) Each of the rudiments of appendages on the second to seventh abdominal segments gives origin to a ventral style and to an eversible vesicle. (3) The tergites of the maxillary segments take but little part * Zool. Anzeig., xx. (1897) pp. 125-8, 232--7. 374 SUMMARY OP CURRENT RESEARCHES RELATING TO in the dorsal covering of the head, bnt they form most of the cheeks. (4) The “ sutures ” on the head of the adult only partially correspond to the original regions in the embryo ; in fact they appear also in places where in embryonic life there are no boundaries. (5) The “ dorsal organ” appears internally in the posterior region of the head. (6) What have been hitherto called labial palps are the lobi externi ; Meinert’s “ verruca oblongae ” are the labial palps. (7) What is called the ligula is formed from the sternite of the first maxillary segment ; the two parts called paraglossae arise from the sternite of the mandi- bular segment ; and the three parts together should really he regarded as hypopharynx. Gonads and External Genital Appendages of Plecoptera.* * * § — Herr Fr. Klapalek was led to study these organs because of their value in classification. This is particularly true of the Plecoptera or Perlidse. He describes a dozen species as regards the structure of the parts in question, and then discusses some related morphological questions. He comes to the general conclusion that both the internal organs and the external parts are more primitive in Perlidse than in any other insects, including the Apterygota. Viviparity of an Ephemerid.f — Sig. A. Coggi returns to a discus- sion of the discovery of viviparity in Cloeon dipterum L. We need not enter into the details, though they have doubtless their interest; the point is that the viviparity of this mayfly, vaguely announced by Siebold, was discovered and studied by Luigi Calori in 1848, and, after having been for long ignored by many, has been recently confirmed. Tetrameric Regeneration of the Tarsus in Phasmidse.J — M. Edmond Bordage has shown that, after autotomy or amputation of a limb in larvae or nymphs of Phasmidse, a regeneration occurs in which the tarsus has only four instead of the usual five joints. He gives particular details in regard to Monandroptera inuncans. Bateson and Brindley have cited such cases in Blattidae as examples of discontinuous variation (“ variation brusque ”), but Bordage thinks it “ much more logical ” to regard the occurrence as an atavism, as a return to an ancestral condition similar to that which may still be seen among the Locustidae. Natural History of Ants.§ — M. Charles Janet publishes an admirable lecture on the habits and life-history of ants. Taking as his type the common little red ant, Myrmica rubra , he first describes the successive stages in the life of the individual, noting, as an instance of abrupt change in animal habit, that while many larvae spin a perfect cocoon, others of the same species spin none at all. He then discusses poly- morphism, comparing the functions and status of the queens and workers of an ant-colony with those of bees and wasps, and tracing the fate of males and young queens after the nuptial flight. The males are allowed to die or are pitilessly killed, while such of the females as can be found are brought back to the nest to add to the number of its queens, and the rest creep away into holes to lay their eggs and laboriously found a new * SB. Akad. Wiss. Wien, cv. (1896) pp. 683-738 (5 pis.). : t Anat. Anzeig., xiii. (1897) pp. 498-9. X Comptes Rendus, cxxiv. (1897) pp. 1536-8. § Paris, 8 vo (au siege de la Soc. Zool. de France), 1896, p. 36. ZOOLOGY AND BOTANY. MICROSCOPY, ETC. 375 colony. Various types of nest are described, and cases are cited where two colonies apparently nest together. Such cases may be (1) mere acci- dental juxtaposition, when two or more colonies seek to take advantage of a specially favoured spot, but have no true association ; (2) there may be double nests, as where Solenopsis fugax makes its tiny galleries within the more massive walls of the nest of Formica fusca, and from that position of vantage steals and devours its neighbours’ nymphs. Or they may be (3) genuine mixed colonies, where two different species live in harmony in one nest. After giving full instructions for the making of an artificial nest which will allow of constant observation of the inmates, the author gives a very graphic account of the daily life of an ant-colony, and the relatively enormous amount of labour required to make and maintain the nest, feed the entire community, and attend to the young. No small portion of this labour consists in daily moving all the eggs and young from chamber to chamber, according to the changes of temperature, The eggs, which are adhesive, are removed in packets, the smaller larvee in bundles attached together by the hooked hairs ( poils d' accrochage) borne among the ordinary defensive hairs, but the larger larvm and the pupee have to be carried one by one. Descriptions are given of the alimentary canal, the changes it undergoes in the larval and pupal stages, and its final adaptation to the"collecting of food and carrying it for distribution ; of the structure of the antennae and their role as sensitive organs, of the organ of stridulation, the man- dibles, and the sting ; of the secretion of the poison-gland, and of the alkaline gland beside it, which may, the author thinks, neutralise the acidity of any venom left in the sting after it has been used. Animals which are parasitic on ants in varying degrees, the relations of colonies among themselves, the development of the instinct of slave-making, and the keeping of pets are all treated of ; and the paper concludes with an account of some remarkable exotic species, e.g. the honey-ants ( Myrme - ^ocystus ) of Mexico and Colorado, and the leaf-cutting ants (Atta fervens and A. discigera ) of Texas and Brazil. Notes on Ants.* — Herr E. Wasmann makes some remarks on a small collection of ants from Madagascar. There were several new species, which will be described by Eorel. In the nests of Cremasto- gaster JRanavalonse For. var. Paulinse-Banavalonee there were numerous myrmecophilous insects of different orders. The beetles seemed to be all new forms, and will be described. Of much interest were some cases of myrmecoidie ” or mimetic resemblance to ants. A form belonging to the Phanapterid Orthoptera, and related to Myrmecopliana fallax Brunn, resembles a small worker of a black Camponotus. Another form belonging to the Hemiptera, suggesting Alydns calcaratus L., is mimetic of a PolyrTiachis. A third form, a spider of the family Attidse, related to Salticus formicarius , resembles a red-headed Odontomachus. In a second short paper,']' Wasmann describes from the same col- lection an ergatoid (worker-like) female of Champomyrmex Coquereli Bog., and gives a list of the species in which ergatoid or ergatomorph forms are known. They are the rule in Tomognathus sublsevis Nyl., * Zool. Anzeig., xx. (1897) pp. 249-50. f Tom. cit., pp. 251-3. 376 SUMMARY OF CURRENT RESEARCHES RELATING TO frequent in Polyergus rufescens Latr., very rare in Myrmica sulcinodis , and so on. The author proceeds to a brief discussion of pseudogynous forms, and notes, in regard to their frequency, that in 315 Sanguinea- colonies in the neighbourhood of Exaeten, 30 contained these interesting transition-forms. Eelations of Antennophorus and Lasius.* * * § — M. Charles Janet gives the results of his observations on the relations of Antennophorus Ulil- manni Haller and Lasius mixtus Nyl. The former is an Acarid which is epizoic upon the ant. It fixes itself on the lower surface of the head, or on the sides of the abdomen by means of the carunculte in which its feet terminate, and which are furnished with an adhesive substance. These mites are blind ; but the first pair of feet is transformed into long antenniform appendages provided with very sensitive olfactory organs. A working ant usually carries only one parasite, but may carry several without beiug hindered from taking part in the work of the colony. The mite attaches itself to the naked nymphs, but never to a- nymph enveloped in a cocoon. Its shows a marked preference for newly hatched nymphs, probably because these are the recipients of much care from the older workers. The presence of the mite is tolerated by the ants, which apparently give it food willingly, and the mite subsists solely on the fluid disgorged by its bearers ; so that it is a case of very advanced myrmecophily. Palps of Butterflies.f — Herr E. Eeuter has studied the palps of 670 species of butterfly, belonging to 302 genera, paying special attention to the external form, the hairy or scaly covering, and the basal spot — a bare space on the inner side of the basal joint — which is striated, pitted, and set with numerous conical hair-scales. The importance of this patient task is of course taxonomic, and the author applies his results to the elaboration of a genealogical tree. The Hesperiidae are regarded as a distinct suborder, and are separated from the Rliopalocera under the name of Grypocera. A Californian Book-Worm.J — Mr. H. G. Hanks describes and figures a larval insect which he found burrowing in his books, and apparently feeding upon the skins and glue used in the binding. It was 5-8 mm. in length, with 13 or 14 silvery-white segments with sparse hairs. The head was amber-coloured, with two antennse which could be retracted into a sheath. Mandibles, three pairs of clawed legs, and five pairs of sucker-like appetfdages, were present. The author does not pretend that his description is a scientific one. Tendons and Muscles of Hymenoptera.§ — M. Charles Janet de- scribes the articular membranes, the tendons, and the muscles, of ants, bees, and wasps. Each muscle consists of a group of fibres, almost always divergent ; one of the insertions is usually expanded, and the other con- densed. At the expanded insertion each fibre is fixed by its whole dia- meter to the chitinous skeleton ; at the condensed insertion each fibre is * Comptes Rendus, cxxiv. (1897) pp. 583-5. Ann. Nat. Hist., 1897, pp. 620-3. t Acta Soc. Fenn., xxii. (1896) 6 pis. Ann. Nat. Hist., xx. (1897) pp. 111-5. j Read at a meeting of the San Francisco Micr. Soc., June 16, 1897 (1 pp., 1 ph). § ‘Etudes sur les Fourmis, les Guepes et les Aheilles,’ 12me note, Limoges, 8vo, 1895, 25 pp. and 11 figs. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 377 received into a little capsule which may be sessile, but is more fre- quently continued into a long chitinous stalk. These fine stalks fuse to form a tendon, which is covered by hypodermis, and has an axial cavity more or less reduced, two details which suggest its origin as an integumentary invagination. Each fibre may be considered as a multinucleated cell, the sarco- lemma representing the cell-membrane. The semi-fluid homogeneous hyaline doubly refractive substance which fills the sarcolemma-tube, has a nutritive function in relation to the longitudinal and radiating fila- ments which are imbedded in it. The longitudinal filaments run parallel to the long axis, and are of course the essential contractile ele- ments ; the radiating filaments follow the surfaces of van Gehuchten’s reseau transversal , and are attached to the sarcolemma, acting as anta- gonists to the pressure of the internal substance, and supporting the longitudinal filaments. The author believes that they also transmit the nervous stimulus to the longitudinal filaments, and restore these to their position after contraction. Association of Mites and Ants.* — M. Charles Janet discusses the association of Discopoma comata Berlese and Lasius mixtus Nylander. Too little, he says, is known in regard to these interesting associations ; the most connected observations are those of Michael, who showed that Lselaps cuneifer , found in the nests of Cam^onotus herculeanus, ate the corpses of the ants and other insects. The Uropod which Janet observed occurs sparsely in the galleries, and in great numbers on the lame of males and queens, and especially on the abdomen of adult workers. An ant may bear from one to six mites. When Janet placed a mite in the nest, the ants attacked it with fury* though they seem to resign themselves to those they carry about. The attack may end fatally ; but very frequently the ant’s mandibles slip on the resistant and flexible carapace of the mite, which is then projected to a distance of 3-4 cm. The mites do not eat either the living larvae or the corpses of the ants ; they use their chelicerse to make minute punctures in the articular membranes of their host, and are true external parasites, absorbing the blood. Prothoracic Gland of Dicranura Vinula.f — Mr. O. H. Latter gives an account of investigations into the function, structure, and homologies of prothoracic glands. Experiments with Dicranura vinula have led him to conclude that in that species there exists a special relation between the undischarged silk and the formic acid secreted by the larva, and that the formic acid is utilised not only for defensive purposes during larval life, but also for rendering the cocoon extremely tenacious, hard, and waterproof. Similar experiments with the silk- glands of other species gave quite different results, and it is probable that the chemical composition of the silk in various species is far from constant. After a resume of the work of other investigators, from De Geer, who in 1745-6 accurately described the main features of the organ in question, the author gives a detailed description of the structure of the * Comptes Eeudus, cxxiv. (1897) pp. 102-5 (4 figs.). t Trans. Entom. Soc. London, 1897, pt. ii. pp. llo-23 (1 pi.). 878 SUMMARY OF CURRENT RESEARCHES RELATING TO prothoracic gland of D. vinula ; and, after a discussion of the homologies of prothoracic glands, he concludes that there exists a fairly complete series which commences with projecting setiparous warts or tubercles surround- ing a glandular opening, and leads up to invaginated spiny (setiparous) tubes placed laterally to the opening of the median gland. This evidence appears to him sufficient to justify the supposition that these lateral structures are directly derived from setiparous projections of a Choetopod ancestor, and he maintains that the spines now present in the lateral tubes of D. vinula and other species are the actual representatives of original setae. The glands under discussion, he concludes, are the homologues of the coxal glands, and of the acicular gland sacs of Chaetopods, while the lateral appendages (spiny projections or tubes) represent groups of parapodial setae. Sympathetic System of Orthoptera.* — L. Bordas has studied the sympathetic nervous system of 25 species belonging to the Phasmidae, Blattidae, Mantidae, Acridiidae, Locustidae, and Gryllidae. There is great uniformity throughout. The system begins at the anterior end of the pharynx in a large dorsal ganglion, the frontal or buccal. This is connected by two large cords with the oesophageal connectives just below the brain, and it gives off from its posterior surface the unpaired re- current or medio- anterior nerve, running to the oesophageal or hypocerebral ganglion, which varies greatly in degree of development. There is also a lateral ganglionic system in the oesophageal region, with two pairs of ganglia with which the unpaired ganglion is connected. The anterior pair are connected with the lower surface of the brain, and with the posterior pair ; they give off numerous branches to the lateral walls of the oesophagus and to the salivary glands. There is indeed an oesophageal plexus. The hypocerebral ganglion gives off posteriorly a posterior recurrent nerve or pair of nerves, with which the paired or unpaired abdominal ganglia are connected. Function-Change in Moulting Hairs of Insects. | — Dr. K. Escherich describes two cases where the cuticular processes or hairs which are of use in loosening the old cuticle take on a new function. (1) In the expanded end of the invaginated ductus ejaculatorius, which Verhoeff calls the praeputium, there are fine spines, hooks, and the like, which help to secure the hold in copulation. These correspond to moulting hairs. (2) On the pleural and intersegmental membranes of some Meloidse (Meloe variegatus, &c.), where there is considerable strain, due to the large number of eggs, there is a variable arrangement of ridges running parallel to the folds of the skin, i.e. at right angles to the folding force. These ridges are, without doubt, strengthening struc- tures, which do not interfere- with the necessary elasticity ; and the author compares their effect to that of a string wound round an india- rubber tube. They also protect the regions left uncovered by the short and delicate elytra. Now it is interesting to find that these ridges sometimes consist of small lamellae, and are doubtless, in all cases, derived from moulting hairs. * Comptes Rendus, cxxv. (1897) pp. 321-3. 1 ^ f Biol. Centralbl., xvii. (1897) pp. 542-4 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 379 The Pear-Borer.* * * § — M. Matsumara describes the adult and the life- history of Nephopteryx rubrizonella Bag., the larger pear-borer of Japan, which destroys 30-50 per cent, of the fruit every year. It was identified by Mr. W. J. Holland of Pittsburg, and belongs to the Microlepidoptera, group Pyradina, family Phycidse. The remedies are, pruning off the branches which bear eggs, the use of kerosene emulsion, and, as a last resource, pouring carbon bisulphide into the hole made in the fruit. j8. IMCyriopoda. A Mysterious Myriopod.f — M. H. W. Brolemann refers under this title to Scolopendra ( Scolopendropsis ) bahiensis Brandt, 1841, the only Scolopendra with 23 segments and possessed of ocelli. No one seems to have observed it since Brandt received it from Bahia in 1840, until Brolemann recently found a specimen in a collection made by M. Gounelle in 1889, in the environs of Bahia. He gives a description of the external characters, and refers, as Pocock has done, to the extra- ordinary resemblance between it and Pithoptus calcar atus Pocock. One slight difference is that the armature of the tarsi in P. calcaratus is absent in Scolopendropsis bahiensis ; but Pocock’s P. inermis , also with- out armature, seems to show that the difference referred to is unim- portant. There remains the fact that Brandt’s species has 23 segments, while Pocock’s has 21, but it may be that the individuals with 23 seg- ments simply express dimorphism or some peculiarity of development. Oviparity of Scolopendra.J — Sig. Filippo Silvestri has observed the female of Scolopendra cingulata Latr., guarding its eggs, which it does most assiduously, and has thus disproved the statement of Gervais and Lucas, not to speak of many text-books, that these Myriopods are viviparous. The eggs had a pale-yellow colour and an elliptical form. It is possible that the mistake arose as an erroneous inference from the way in which the mother animal guards its young ones. Morphology and Classification of Diplopoda.§ — Dr. C. Verhoeff concludes his prolonged series of studies on Diplopoda. This part deals with (a) Chordeumidae (including descriptions of two new genera* Heterobraueria and Bielzia, and several new species), and ( b ) Iulidee (including the new genus Stenophyllum , and several new species). S. Araclmida. Development of Phrynidae.|| — Mdlle. S. Pereyaslawzewa has studied the first stages in the development of Tarantula palmata Herbst, Phrynus niedius Herbst, and Pliryniscus bacillifer Gerstaecker. (1) In the first form the spherical ova showed a white spot covering about a third of the surface. Sections demonstrated this to be a blasto- derm, with the three embryonic layers, and with the rudiments of thoracic limbs and nervous system. (2) In the second form the blastoderm surrounded the whole egg ; * Annot. Zool. Japon., i. (1897) pp. 1-3 (1 pi.). f Bull. Soc. Zool. France, xxii. (1897) pp. 142-6. X Atti E. Acead. Liucei (Rend.), vi. (1897) pp. 56-7. § Zool. Anzeig., xx. (1897) pp. 97-125 (14 figs.). II Comptes Rendus, cxxv. (1897) pp. 319-21. 380 SUMMARY OF CURRENT RESEARCHES RELATING TO the thoracic limbs and the two lateral organs above the third pair were already large, and the embryo was folded in two halves. A very thick cuticle covered the embryo, and bore papilla) into which the ectodermic cells protruded ; the mesoderm was thickest in the dorsal median line where the heart appears ; the nervous system consisted of two distinct bands of nerve-cells ; the segmentation of the abdomen was very faint ; the endoderm was not yet a continuous layer ; a deep invagination above each chelicera formed the ganglion of the median eye. (3) In the third form the appendages were much longer ; the lateral organs still existed ; the cephalothorax was defined from the abdomen ; the ganglia were established ; the segmentation of the abdomen w'as marked only by lateral mesodermic buds; the mesoderm cells of the appendages were beginning to form muscle groups, and the somatic layer was distiuguishable from the splanchnic ; the oesophagus and rectum had not yet united with the slowly developing endoderm. Galeodidse.* — Mr. H. M. Bernard gives a very interesting account of the Galeodidae or “ wind-scorpions.” The popular name is translated from the Arabic, and refers to their swiftness of movement. One observer compares them to “ a piece of thistle-down driven before the wind.” They do not make webs like spiders, but “ run down ” various insects, even hard beetles. Some feed on scorpions, others are reported to hunt bed-bugs. Some are nocturnal, others “ run about the streets in broad daylight.” The jaws consist of a pair of stout pincers, projecting straight out in front, with sharp curved points, inner teeth, and external bristles. Size apart, they are the most horrible jaws in the whole animal kingdom. They are worked alternately in a sort of sawing motion, cutting deeper and deeper into the victim. The next pair of limbs, remarkable for their length, wave in the air as if to “ interrogate space,” and bear in an invagination at their tips a remarkable protrusible “ smelling ” organ, which some have mistaken for a sucker. The mouth is a very minute aperture at the end of a rigid beak, which has at its tip a lattice-like sieve of fringing bristles. Lich- tenstein has suggested that the “ mice ” and the “ emerods ” by which the Philistines were punished on a memorable occasion were respectively wind-scorpions and the sores caused by their bites. The fact seems to be that they only bite men accidentally, but if they bite, they bite badly. The German name for Galeodes is “ Gift-Kanker,” but no poison-glands are known. Perhaps the violent inflammation set up by the bite is due to exudation of (excretory) matter through the setal pores. It seems likely that the very varied bristles and hairs on the body, especially on the legs, are protective. The legs have long curved claws with movable tips. In some species there are stridulating ridges, different in character from the apparatus in spiders. The last pair of legs bear stalked fan-shaped sensory “ raquet ” organs, five on each. Like the pectines of the scorpion, they are pro- bably associated with reproductive processes. Mr. Bernard confirms Johannes Muller’s discredited observation that there are six eyes ; the lateral pairs are degenerate, and difficult to find. The female is said to attack and devour the male as soon as she has * Science Progress, i. (1897) pp. 317-43. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 381 received tlie spermatophores, but she takes good care of the eggs and young. After this introduction the author proceeds to consider the anatomy of the Galeodidm in its relation to that of other Arachnids, in order to show how near we may thus come to “ a reconstruction of an ancestral form capable of producing all the known Arachnids.” He discusses the segmentation, the waist or diaphragm, the degeneration of the abdo- minal limbs, the tracheae, the number of stigmata, the endo-skeleton, and the possible connection between bristle-formation and gland-forma- tion. We must content ourselves, however, with citing the author’s “ reconstruction.” “We must picture to ourselves a loosely segmented hairy creature, showing a slight waist-like constriction between the sixth and seventh segments. The first three segments are fused together, and distorted in such a way as to range two pairs of limbs round an anterior mouth which is at the tip of a kind of beak, These limbs are specialised for seizing prey and crushing it in front of the mouth. The four following pairs of limbs are used for locomotion, while those of the segments behind the waist, which are often swelled up by liquid food, are more or less riseless and degenerating. This, in brief, would represent the form from which, by modification and specialisation in various directions, all the existing Arachnida could be derived.” Notes on Hydrachnidse.* — Mr. C. D. Soar has 'collected in one season 32 species, representing 15 genera, within a radius of 20 miles round London. He makes brief notes on (1) the eggs and the variable period (12-38 days) required for hatching in different genera ; (2) the hexapod larvae and their diverse habits ; (3) the free-swimming nymphs with eight legs; and (4) the adults with their well-known brilliant colouring. g. Crustacea. Segmentation of Nebalia Ovum.f — Dr. P. Butschinsky describes the segmentation and the formation of the blastoderm in the eggs of this Crustacean. There is a large quantity of yolk, the main mass of which forms a granular clump in the centre, enclosing the nucleus. A thin protoplasmic layer lies peripherally around the egg. The mode of cleavage is of an intermediate character between the discoidal and the peripheral types. New Subterranean Isopods.]: — M. Adrien Dollfus first describes Sphseromides Raymondi g. et sp. n., found by P. Raymond in a Cevennes grotto. The body is oval and elongated (16 mm.); the first pair of antennae are shorter and more delicate than the second pair ; the mesepistoma is narrow and elongated ; the eyes are absent ; the pereion has the coxal parts well developed on segments 2—7 ; the posterior pereiopods are delicate, and those.of the first three pairs are prehensile ; the pleon has five free segments, the sixth having fused with the telson ; the uropods are subequal. The author then describes Stenasellus Virei g. et sp. n., a vermiform * Journ. Quekett Micr. Club, vi. (1897) pp. 318-21. t Zool. Anzeig., xx. (1897) pp. 219-20 (1 fig.). J Compte3 Rendus, cxxv. (1897) pp. 130-31. 382 SUMMARY OF CURRENT RESEARCHES RELATING TO Asellid, found by A. Vire in a Cevennes well. The body is very narrow ; the head is closely united to the first pereial segment ; the first pair of antennas are shorter than the second ; there are olfactory hairs, but no eyes ; on the segments 2-7 of the pereion, the coxal parts are very small ; the first pair of pereiopods have elongated protopodites ; the succeeding limbs are delicate ; the pleon has the first three segments free and much developed ; the pleotelson is oblong and elongated ; the uropods are greatly developed. It is premature to say that these are archaic forms, relics of a Tertiary marine fauna ; but there is no doubt as to their interest. Sense-Organs of Subterranean Crustaceans.* — M. Armand Vire has previously noticed in regard to cave-animals that, as the eye disappears, other sense-organs become hypertrophied and acquire a new delicacy. He confirms this in reference to the two Isopods described by Dollfus. In Sjphseromides Baymondi there are remarkable tactile hairs ; some are straight, rigid, and unbranched ; others, especially on the antennae and limbs, are slightly jointed at the base, and, about half-way up, swell and give off minute secondary hairs of great mobility and delicacy. The author does not give any histological or other proof that the hairs are tactile ; but one must remember the preciousness of the specimen. The olfactory organs were crushed. In Stenasellus Virei the tactile hairs resemble those above mentioned. The olfactory organs consist of flattened lamellae supported on a stalk which is articulated to the end of each segment of the antennule. A very interesting series is noted. In Asellus aquations, from the brooks round Paris, the organ is hardly half the length of one of the segments of the antenna ; in the same species living in darkness in the subterranean water-conduits of the city it is almost as long as a segment ; in those from the catacombs of Paris it exceeds the length of a segment ; in Stenasellus it is more than one-and-a-half times the length of a segment. The reverse is true of the eye : it is black and well-developed in the Asellus of the brooks ; it is paler in those from the conduits ; it is re- presented only by red points in those from the catacombs ; in Stenasellus it is quite absent. The series confirms “ Geoffroy Saint-Hilaire’s law of the balance of organs, and Darwin’s theories of the influence of environ- ment.” Eye of Corycseus.j* — Dr. A. Steuer makes a preliminary communica- tion as to the structure and function of the eye in Corycseus anglicu & Lubbock, a Copepod related to Copilia which Exner investigated. The frontal margin shows the usual large lens, connected by a conical tube (eye-sheath), with the internal pigment-rod, which bears a Secretkugel ( Secretlinse ) at its cup-shaped anterior end. As in other Corycseidse, the frontal lens consists of two parts, and on the inner side there is a non-cellular part hitherto overlooked, The eye-sheath is a complete, finely fibrous tube, containing only blood. At the end of the pigment- rod are seen the optic cells and the cylindrical optic rods. At the upper part of the pigment-rod and to the ventral side, lies the so- * Comptes Reiidus, cxxv. (1897) pp. 131-2. f Zool. Anzeig., xx. (1897) pp. 229-32. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 383 called accessory lens, probably comparable to the pigmented “ clear sphere ” in Copilia, and apparently innervated by the optic nerve. The pigment not only surrounds the optic rods, but forms partitions and tubes in the interior. There are three optic rods, of unequal thick- ness, and twisted like a screw round 360°. The pigment-rod itself is notched in the middle, and thereabouts the optic nerve enters. Gegenbaur compared this remarkable eye to a telescope, and sup- posed that rhythmic longitudinal movements of the pigment-rod secured accommodation by bringing the crystalline sphere ( SecretJcugel ) nearer the cornea. Exner fixed his attention on supposed lateral movements of the pigment-rods, which he suggested might enable the terminal nervous apparatus to sample the image which is formed by the frontal lens, but is too large to be appreciated as a whole. But Steuer was unable to detect anything but the rhythmic movements of the gut which have an influence on the eyes. He cannot accept either Gegenbaur’s or Exner’s theory, but refrains from suggesting as yet what his own view is. The Genus Sympagurus.* — MM. A. Milne-Edwards and E. L. Bou- vier discuss this genus, which closely resembles Parapagurus, except that the branchial lamellae have become biserial, and the false genital appen- dages have a tendency to disappear. Eight species are known, and of these a diagnostic table is given. A new species, Sympagurus Grimaldii, is described. Systematic Notes on Copepods.f — Dr. W. Giesbreclit makes a number of corrections and additions. Boeck’s insufficiently described Pseudocalanus elongatus is not the same form as that which Brady de- scribed by that name ; the latter must be referred to a new genus Bradyidius, related to Aetidius. Scott’s Amallophora , proposed as a sub- genus of Scolecithrix Brady, belongs to the genus Xantliocalanus Giesbr. ; Scott’s Pleuromma princeps belongs to Metridia ; in both these cases the specific name must be changed ; and Giesbrecht proposes Scotti. The hitherto unknown female of Arietellus setosus Giesbr. is described. Tlio form which Scott describes as Labidocera Darwinii Lubbock is a distinct species, L. Scotti. As to Scott’s Paracartia spinicaudata and P. dubia , they are respectively the female and male of a species of Acartia (A. dubia), nearly related to I. C. Thompson’s A. verrucosa. New Edriophthalma from Irish Seas.J — Mr. A. O. Walker describes Leuconopsis g. n., resembling Leucon in many ways, but distinguished as follows. The female has a distinct two-jointed appendage to the fourth pair of feet, not furnished with natatory setas ; the lower antennae are short, with the third joint conical, with three minute one-jointed rudimentary flagella ; the rami of the uropods are subequal ; the male has a pair of curved blade-like processes on the second joint of the third pair of feet. One species is known, L. ensifer. * Bull. Soc. Zool. France, xxii. (1897) pp. 131-6. t Zool. Anzeig., xx. (1897) pp. 258-5. + Journ. Linu. Soc. (Zool.), xxvi. (1897) pp. 226-32 (2 pis.). 2 E 1897 384 SUMMARY OF CURRENT RESEARCHES RELATING TO He also describes Apseudes liibernicus sp. n., Stenothoe crassicornis A. O. Walker, and Parapleustes megacheir sp. n., a form which may be at once distinguished from all other species of the genus by the shape and large relative size of the second gnathopods. Phosphorescence of Cypridina Hilgendorfii.* — Mr. H. Watanabe finds that the phosphorescent organ of this Ostracod, “ the sea firefly,” is a group of elongated unicellular epidermal glands opening to the exterior symmetrically on either side of the median line, on the outer edge of the upper lip (Claus’s Oberlippendriise, 1873). They secrete transparent colourless “ secretive vacuoles ” and yellow homogeneous granules, which are stored in the necks of the glands. Physical and chemical stimuli cause contraction of the muscles of the upper lip, and the secretion of the glands is thereby squeezed out. The phosphorescence is a chemical phenomenon accompanying the contact of the pigment of the granules with the sea-water. Free oxygen in any considerable quantity is not essential, but the presence of water, unless it be strongly acid, is a necessary condition. “ As the phos- phorescent organs of the Metazoa seem to be generally derived from a glandular transformation of the ectoderm, so physiologically they are attributable to a pigment-producing change in the glands; the phosphorescence being simply a collateral phenomenon due to con- tact of a yellowish pigment, capable of changing into red or green, with water. It is, generally speaking, a means of frightening other animals, possessed by certain aquatic organisms, or those living in a moist medium.” New Ostracods.f — Prof. G. S. Brady describes some Ostracods — residues of the ‘ Challenger ’ collection and from other sources — belong- ing to the section Myodocopa. In the family Cypridinidae, the new genus Cyclasterope is established beside Asterope, with two new species. The following are also new : — Cypridina castanea , C. (?) armata, C. (?) squamosa , Philomedes corrugata. Annulata. Nephridia of Polychseta.J — Mr. E. S. Goodrich describes the nephridia of Hesione sicula Dch., TyrrJiena Claparedii Quatref., and Nephthys scolopendroides Dch. He begins with the ciliated organ of Hesione. It is crescent-shaped, with two free horns, and lies at the point where the dorso-lateral blood-vessel first touches the hinder edge of the oblique muscles. The surface which faces backwards and away from the muscle is deeply grooved and densely ciliated ; the anterior surface towards the muscle is lined with flat ccelomic epithelium. There is no trace of glandular structure. A pair of ciliated organs occurs in the anterior region of every segment after the third parapodium. The nephridium opens into the coelom by a simple funnel with long stiff curved cilia ; a narrow neck leads to a wide and somewhat twisted tube ; this becomes narrower and more convoluted, forming a mass * Annot. Zool. Japon., i. (1897) pp. 69-70. f Trans. Zool. Soc. London, xiv. (1897) pp. 85-100 (3 pis.), j Quart. Journ. Micr, Sci., xl. (1897) pp. 185-95 (4 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 385 flattened dorso-ventrally, stretching backwards on the floor of the segment. Finally it widens slightly, and opens below the base of the parapodium. Nephridia occur in all the segments which have ciliated organs, and the lip of the nephrostome is directly continuous with the ventral prolongation of the ciliated organ. In Tyrrhena the condition of ciliated organs and nephridia is very much the same as in Hesione. In Nephthys the ciliated organ is somewhat like the shell of Peclen , smaller and more rounded than in Hesione, with no communication with the lumen of the nephridium. In both sexes there is a pair of ciliated organs in every segment except about the first ten. The nephridium of Nephthys is remarkable. It has no internal opening, but ends in a hunch of short blind branches, composed of unique “ tube-b6aring ” cells with flagella. There is an internal cur- rent towards the external pore, and it seems likely that excretion takes place through the walls. Possibly the thin-walled tubes in which the flagella work act as osmotic filters, while solid excretory products may be conveyed to the lumen of the canal by the cells themselves. The morphological interest of the facts will be discussed in a subsequent paper. Phagocytic Organs in Marine Annelids.* — Dr. J. Cantacuzene has made observations on Nephthys margaritacea, Glycera convoluta, Arenicola piscatorum , and Spirographis Spallanzanii , as regards their phagocytosis. His method was to inject carmine (in suspension in sea-water) into the body-cavity, and to investigate the points where the colour was tem- porarily localised. It may be noted at the outset that the carmine was never found free after 48 hours. The phagocyte apparatus is represented by (1) the amcebocytes ; (2) the endothelial cells of the coelome and their fixed derivatives, the lymphoid glands or masses ; and (3) the nephridial cells. The endo- thelial cells which act as phagocytes lose their flat shape, and project singly or in groups into the general cavity, especially in the parapodia. The lymphoid masses result from the proliferation of endothelial cells, and occur both irregularly and quite symmetrically. In the nephridial cells the carmine was always localised between the nucleus and the free margin of the cell. In all cases the solid particles are enclosed in a vacuole or lacuna, the contents of which become rose-coloured as the carmine passes into liquid form. Structure and Development of Spirorbis borealis.f — Mary A. Schwely has studied this Chsetopod. There are 14-20 segments; the prostomium bears eight branchiae (including the operculum ; prostomium and peristomium coalesce in a buccal somite; thoracic and abdominal regions are distinguishable ; the parapodia are very slightly developed ; the alimentary system consists of a short fore-gut, a short hind-gut, and a long mid-gut ; the gut is surrounded by a blood-sinus ; the shell-gland lies in the anterior thoracic region, in the median ventral line. The body undergoes considerable modification during development, being greatly influenced by the shell. The animal is hermaphrodite, and has * Comptes Rendus, exxv. (1897) pp. 326-8. t Proc. Acad. Sci. Philad, 1897, pp. 153-60 (2 pis.). 2 E 2 386 SUMMARY OF CURRENT RESEARCHES RELATING TO two breeding periods in summer ; the gonads lie on each side of the gut on the walls of the body-cavity ; the eggs pass into the operculum, where they are fertilised ; the operculum does not, however, serve as a brood- pouch, as in Sp. spirillum ; the encapsuled eggs lie in a long mem- branous sac along the mid-dorsal furrow. The eggs are telolecithal, with considerable nutritive yolk. The blastula has a small blastocoele ; a gastrula is formed by invagination. Nine larval stages are described, which follow one another in rapid and direct succession in the three days between the first segmentation and the emergence of the free-swimming ciliated form. Septal Valves of Owenia.* * * § — Prof. G. Gilson continues his study of Oivenia. (1) The perivisceral compartments are less numerous than the metameres; details of the relation are given. (2) The septa are not complete ; some show gaps at their attachment to the body-wall, others have perforations, others have holes surrounded by a muscular sphincter. Several septa have both marginal gaps and sphinctered apertures. (3) The coelomic cavity of certain metameres is in communication with the exterior. The sixth shows in the female a ciliated funnel applied to the third septum, and provided with a short canal which perforates the wall and enters an epithelial sinuous tube lodged in the epidermis. In the male there are two pairs. In both cases they are genital. At the level of septa v. and vii. there are two epidermic invaginations in the ^thick- ness of the septa ; each ends at the sphincter, and perhaps opens into the body- cavity. Less developed structures occur in most of the septa. (4) The genital funnels arc probably modified nephridia. The epithelial tubes may have the same significance. Perhaps the septal canals and Ihe sphincters may be vestiges of nephrostomes. The secretory function of the true nephridia has totally disappeared. New Species of Perichaeta.f — Dr. W. B. Benham describes and gives diagnoses of five new species — Perichseta novse britannicse, P. Sedgiciclcii, P. Arluri, P. Floweri, and P. Madelinse. The first three are from New Britain, the other two from Singapore and Borneo respectively. He also describes P. malamaniensis, which he named in 1891. At the end of his paper, Benham offers some remarks on Michaelsen’s criticism of the value of certain specific characters of the genus. New Species of Earthworm.^ — Dr. W. Michaelsen describes three new species obtained from the Hamburg Botanic Garden, but really belonging to the West Indies and South America, viz. Tykonus pere- grinus, T. wiengreeni, Criodrilus breymanni. Chaetognatha of Misaki.§ — Mr. T. Aida gives a list, with descrip- tive notes, of twelve species of Chastognatha which he collected in Misaki harbour. He follows the classification of Langerhans, and describes four of the forms he found as new, viz. Sagitta neglecta , a very small form * La Cellule, xii. (1897) pp. 377-416 (3 pis). t Journ. Linn. Soc. (Zoo!.), xxvi. (1897) pp. 198-225 (2 pis. and 4 figs.). X Zool. Jalirb. (Abth. Anat.), x. (1897) pp. 359-88 (1 pi.). § Annot. Zool. J&pon., i. (1897) pp. 13-21 (1 pi. and 1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 387 (7 mm. in length) ; S. regularise in which the tactile prominences are exceedingly regular, and the epidermis is especially thick anteriorly, so that the head is not constricted from the body as in other species ; Krohnia foliacea , with a single pair of lateral fins of remarkable size, extending from before the abdominal ganglion to the middle of the caudal segment; and K. pacifica, which is easily distinguished by its faintly yellowish-green epidermis, and ovaries of the same colour. Rotatoria. Rotifer Commensal with Caddis-Worm.* — Mr. Hy. Scherren re- cords having found Callidina parasitica inside the case of the larva of Phryganea grandis. This Callidina is usually found attached to the gill- plates of Gammarus pulex and Asellus aquaticus, where it takes advantage of the current of water over the gills. Mastigocerca hamata sp. n.f — Dr. 0. Zacharias figures and describes this new species found in a gathering of plankton from a small lake in Upper Silesia. Its principal characteristic is a long curved frontal hook ; the toe is nearly as long as the body. Nematohelminth.es. Epidermic Nuclei of Anguillulidse.J — M. Joannes Chatin discusses the structure of the epidermis or hypodermis of Nematodes, concerning which there has been prolonged dispute. The integument of a Nema- tode in the adult state, or in some types at certain stages of development, shows beneath the cuticle a granular layer of a plasmodial appearance, with scattered nuclei. This epidermis is interpreted by some as a case of free nuclei without protoplasmic territories. Others regard it as only secondarily syncytial, produced by a coalescence of cellular elements. The second view was maintained by Chatin in 1888 and 1891 ; but, as he has been recently cited as an upholder of the first interpretation, he has restated his position. Moreover, he has found clear corroboration in studying Tylenchus , Heterodera , and various Anguillulidas. There the epidermis or hypodermis is at first distinctly cellular, but as it becomes older the boundaries disappear and the territories fuse. New Classification of Gordiidae.§ — Prof. L. Camerano divides Gor- diidae into four genera, the diagnoses of which take especial account of the posterior ends of male and female, and of the external structure of the cuticle. These genera are : — Chordodes (Creplin) Mobius, with 27 species, Parachordodes g. n., with 15 species, Paragovdius g. n., with 4 species, and Gordius Linn., with 13 species. There remain 30 species inquirendae. The author thinks the family should be made into an order Gordiacea, with, as H. B. Ward suggests, two families: — Nectonemidae and Gord:- idae. His views as to general relationships are indicated in this Stamm - baum : — * Nature, lvi. (1897) p. 224. t Forschungsberichte Biol. Station Plon, v. (1897) p. 8. j Comptes Kendus, cxxv. (1897) pp. 57-9. § Zool. Anzeig., xx. (1897) pp. 225-9. 388 SUMMARY OF CURRENT RESEARCHES RELATING TO Gordiacea Nematoda Gordiidas Nectonemidae o B Si o' fcJ- c B B' Kinorhyncha Acantliocepliala I Annelida Provermalia (Haeckel) Excretory Organs of Ascarids.* — Prof. J. W. Spengel has some notes on a recent paper by N. Nassonow, which described four peculiar stellate organs in the body-cavity of Ascaris megalocephala and A. lumbri- coides. Spengel and his assistant, Dr. K. Camillo Schneider, also observed these organs, and on looking up the literature, found them described in Anton Schneider’s Monograph on Nematodes. Thus, Nassonow is hardly their discoverer, especially as Schneider refers to a description of them by Bojanus in 1818 and 1821, and by Lieberkiihn in 1855. They were afterwards noted by Leuckart, Hamann, and Linstow. The moral is a painfully obvious one, that discovery must be preceded by an adequate study of the literature, to which this Journal is a readily available aid. Prof. Spengel says in conclusion, that he will add only one item of fact to the previous studies of the remarkable structures in question, namely, that they are not always lateral, between the gut and the lateral lines, but are sometimes also median, on or under the gut. Nematode Parasite from Mantis.! — Mr. 0. Collett describes an aproctous Nematode of the family Mermithidae, 1/30 in. in diameter, 2 ft. 3J in. in length, found in the stomach of a specimen of Mantis religiosa which measured 2^ in. in length. Platyhelminth.es. Diploposthe lsevis.* — Dr. A. Jacobi describes this remarkable tape- worm which occurs as a parasite in wild ducks. It is noteworthy because in each proglottis the genital ducts (vas deferens and vagina) are double, while the essential reproductive organs are single. The author describes the skin and musculature, the excretory system and nerves, and the gonads in particular. In sj)ite of the partial duplication of the repro- * Zool. Anzeig., xx. (1897) pp. 245-8. f Journ. R. Asiatic Soc., xiv. (1896) 2 pp. (1 pi.). J Zool. Jahrb., x. (1897) pp. 287-306 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 389 ductive apparatus, and several less obvious peculiarities, tlie structure of Diploposthe Isevis Dies, is essentially simple, and recalls the Micro- taenia; of mammals, e.g. Tsenia diminuta Rud. and T. relicta Zsch. Gonads of Amabilia.* * * § — Dr. Y. Diamare describes the gonads of the remarkable tapeworm Amabilia lamelligera ( = Tsenia lamelligera Owen, and probably = T. macrorhyncha Rudolplii). Owen noted the remark- able lamellar structures on the sides of the proglottides, and the presence of a penis on each side ; but the peculiarities do not end here. The author sums up in the following diagnosis: — There are two penes, the end-organs of a single vas deferens, which runs in a zigzag from one end of the joint to the other ; the testes are in the form of fine clusters like grape-bunches, and occupy the upper surface of the joint ; the single almost straight vagina lies across the vas deferens ventrally, and is in close connection with it ; it opens on the middle line both dorsally and ventrally ; the ovary is single and median, and the oviduct is also single ; the yolk-gland has many lobes and a long yolk-duct ; the uterus is like a flattened cage enclosing the ovaries : the eggs are enclosed in spindle- shaped capsules. In the course of some systematic notes, the author expresses his conviction that the genus Diploposthe , recently proposed by Jacobi, is an unnecessary synonym for Amabilia , and that T. Isevis St. is either A. lamelligera or a related species. Cysticercus venusta.f — Mr. T. B. Rosseter found this new Cysii- cercus in Cypris cinerea , along with Cysticercus gracilis and C. coronula. After repeated failures he succeeded in rearing the tapeworm in the domestic duck. After comparing it in detail with the other (six) tape- worms of birds whose rostellum bears eight hooks, he finds himself justified in establishing a new species — Tsenia venusta. Cysticercus of Taenia liophallus.f — Mr. T. B. Rosseter has succeeded in finding the hitherto unknown Cysticercus stage of Tsenia liophallus , a parasite of the swan and probably also of the duck. The bladder-worm was found in Cypris cinerea in an old pond near Canterbury. Studies on Tetrarhyncha.§ — Dr. Th. Pintner describes a Tetra- rhynch larval form found in the muscle of a fish which was in process of digestion in the stomach of species of Heptanchus. His study is espe- cially noteworthy, because of the discovery of a new organ. On each side of the body-margin, sometimes just above the excretory vessels, sometimes between these and the more lateral nerve-strand, there is a canal with delicate walls and variable diameter. At the anterior end it bends round in an arch, like the excretory vessels and nervous system. On the margin of the bladder posteriorly it becomes more irregular, and gives off small branches which, by uniting again with the main canal, enclose little islands. In the region of the excretory vesicle it seems to break up into a sort of plexus. Sections show that the whole canal is * Centralbl. f. Bakt. u. Par., xxi. (1897) pp. 862-72 (8 figs.). t Journ. Quekett Micr. Club, vi. (1897) pp. 305-13 (2 pis.). X Tom. cit., pp. 314-7. § SB. K. Akad. Wiss. Wien, cv. (1896) pp. 652-82 (4 pis.). 390 SUMMARY OF CURRENT RESEARCHES RELATING TO formed from a strand of cells united in a kind of syncytium, and traversing the lumen with a complex series of bridges and strands. At tho boundary between scolex and bladder the canal in question is doubled, but it could not be followed up into the scolex, where perhaps the riddle of its nature may be solved. That it is not part of the excre- tory system seems the only certainty. The paper ends with a discussion of the excretory system in other Cestodes. Musculature and Sensory Cells of Trematodes.* — Dr. H. Bettendorf has investigated Distomum hepaticum L., D. cylindraceum Zed., D. crys- tallinum Hud., D. clavigerum Rud., Diplodiscus subclavatus Goeze, and Polystomum integer rimum Frol., and various young stages of Trematodes, with particular reference to the musculature and sensory cells. He used Golgi’s chrome-silver method and Ehrlich’s methylen-blue method. His main results are the following: — (1) The muscles of Trematodes retain very markedly their cellular character, the contractile elements remaining in connection with the large nucleated formative elements or myoblasts. The latter are either in direct contact with the fibres, or are united to them by plasmic pro- cesses. Thus transitions from the Nematoid to the Annulate type are in evidence. The innervation of the muscles is partly through the myoblasts, partly by direct connection with the fibres. (2) The whole body of the Trematode is surrounded by a richly ramified nervous plexus, which lies directly beneath the peripheral muscles. The nerve-fibres which arise from this plexus, as also from the longitudinal nerves and the annular commissures connecting them, pass either to the musculature (motor fibres) or to specific sense-cells (sensory fibres). These sense-cells, which have terminal vesicles in the cuticula, are distributed over the whole body, but are most numerous in the suckers. Epithelium of Triclads.j — Dr. R. Jander has studied the peculiar state of the epithelium in Dindrocoelum lacteum Orst., D. punctatum Pallas, Planaria polychroa 0. Selim., Polycelis nigra 0. F. Miill., Gunda ulvse Orst., &c. He describes the structure of the pharyngeal lining and its connection with the other tissues of the pharynx, the modifica- tion of the simple epithelial cells of the completed embryonic pharynx into the peculiar lining found in the adult, and the new formation of the pharyngeal lining after injuries. llis most important result is that tho pharynx in Triclads (and Polyclads as well) is lined by a genuine epithelium of ciliated cells, which have by no means lost their cellular character, though they are much modified. The cells which line the completed pharynx in the embryo persist in the adult, but they are divided into (a) a part which serves mainly to protect the pharynx, viz. the ciliated plate, and (h) a part which sustains the cell-life, viz. the deep-growing nucleated process. Many analogous differentiations are known in epithelial cells, and the author suggests the application of his results to other Platyhel- minthes. * Zool. Jahrb. (Abtli. Anal.), x. (1897) pp. 307-58 (5 pis., 1 fig.), t Tom. cit., pp. 157-201 (3 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 391 Echinoderma. Brood. Care in Holothurians.* — Prof. H. Ludwig has discovered some new cases of this interesting habit. In Chiridota contorta , in which the sexes are separate, the genital tabes function as brood- chambers in which the whole development occurs. Thus this species is practically viviparous. The author also finds f that Psolus antarcticus carries its young on the ventral surface which is flattened for creeping purposes. On the best specimen there were 22 young ones fastened by their tube-feet to the naked area of the sole. By this discovery the number of Holo- thurians exhibiting prolonged attachment between the young ones and the mother is raised to nine. Five of these are antarctic and one is arctic. The relatively large number of antarctic forms is remarkable ; but even more interesting is the fact that each of the five has its young attached in a different way. In Psolus ephippifer the young develop among the dorsal plates; in Cucumaria' crocea on the modified dorsal ambulacra ; in Cucumaria Isevigata in ventral pouches ; in Cliirodota contorta in the genital tubes ; and in the present case on the ventral sole. Changes in Calcareous Deposits of Stichopus.j: — Prof. K. Mitsukuri has observed interesting changes which occur with advancing age in the calcareous bodies in Stichopus japonicus Selenka, of which, it may be noted in passing, Theel’s variety typicus is only a growth-stage, and Selenka’s Holothuria armata a northern variety. The form of the calcareous bodies (apart from the terminal discs and supporting rods of the tube-feet, which are not discussed) changes with age. The youngest individuals have most perfectly formed large-sized tables, and nothing but these. As the animal grows, perfectly formed tables decrease in number and size, and occur mixed with various stages of arrested development. In fully grown individuals there are only small perforated plates, representing merely a small central part of the basal disc and without any trace of the spire. In comparison with the thickly crowded or even overlapping tables of the young forms, those of the adult are sparsely scattered. As Mitsukuri notices, it is unlikely that these changes occur only in Stichopus japonicus ; if they are general the fact will have an important bearing on the classification of Holo- thurians. New Zealand Echinoderms.§ — Mr. T. W. Kirk describes a collection of these, including Evechinus chloroticus Valenciennes, of which Prof. Jeffrey Bell’s E. rarituberculalus is said to be the young form; Ophiopeza Danbyi sp. n., distinguishable from all other species of the genus by the small number of arm-spines (4) and their large size ; Ampliiura pusilla sp. n., very nearly allied to A. constricta Lyman ; Asteropsis imperialis sp. n. ; and some others. New Species of Asthenosoma.|| — S. Yoshiwara describes two new species of these Echinoids — Asthenosoma longispinum , from 313-376 * Zool. Anzeig., xx. (1897) pp. 217-9. t Tom. cit., pp. 237-9. 1 Annot. Zool. Japon., i. (1897) pp. 31-42 (3 fig?.). § Journ. Linn. Soc. (Zool.), xxvi. (1897) pp. 186-98 (2 pis.). || Annot. Zool. Japon., i. (1897) pp. 5-11 (1 pi.). 392 SUMMARY OF CURRENT RESEARCHES RELATING TO fathoms in the Sagami Sea, distinguishable by the presence of very long spines on the abactinal, and of hoof-capped spines on the actinal side ; and A. Ijimai , distinguished by the peculiar arrangement of the primary tubercles. Ccelentera. Structure of Hydractinia.* — Miss M. C. Collcutt has studied the structure and relative positions of the coenosarc and chitinous parts in Hydractinia echinata. The chitinous skeleton is for the most part a continuous irregular crust attached to some foreign body, and overlaid by a coenosarc consisting of two layers of ectoderm, enclosing between them a number of branching and anastomosing endodermic tubes. These tubes are connected at intervals with the endodermic canals of the polyps, the upper layer of ectoderm being continuous with the ectoderm of the polyps. As is well known, the colonies are common on whelk-shells inhabited by hermit-crabs. A large colony may cover the whole shell except the roundish patch which rubs along the ground ; a small colony is usually situated near the edge of the shell ; a Polychaete worm, Nereis bilineata , was always found along with the hermit crab. A colony consists of— (1) gasterozooids or nutritive polyps, (2) blasto- styles or reproductive polyps, (3) dactylozooids or spiral polyps, and (4) tentacular polyps. The gasterozooids are naturally most numerous, but in early spring and in summer the blastostyles increase greatly in numbers, and at these times give rise to the genital products. The colonies are either male or female. The dactylozooids are situated around the shell mouth ; they are capable of coiling themselves spirally, and may function as defensive polyps. Miss Collcutt has succeeded in demonstrating the presence of a mouth, which Allman and Strethill- Wright failed to notice. She also gives evidence of the migration of ova between ectoderm and endoderm in the blastostyle. The histology of the two layers is described in detail. Stinging Cells, f — Prof. R. von Lendenfeld furnishes an up-to-date account of the stinging-cells of Cnidaria. He gives a list of the litera- ture since 1887, and then sums up the facts in regard to the structure, development, and function of the elements in question. Among the steps of progress the following may be noted. The stinging cells are either modified gland-cells (Lendenfeld and Schneider), or modified epithelial cells (Iwanzoff). There is an essential difference between nematocysts and spirocysts (Bedot). The muscular nature of the stalk (Chun) has not been confirmed ; it is doubtful whether even the mantle is muscular. All later authors agree that the wall of the capsule is two-layered. According to the majority, the thread is a con- tinuation of the inner layer ; Iwanzoff represents the opinion that it is a continuation of the outer, or of both. The spirocyst thread is always smooth; the nematocyst-thread has normally three spiral ridges of spines, usually larger at the base. They probably increase the thread’s power of penetrating and boring. As to the explosion, the hygroscopic nature of the capsule contents explains the increased tension when water * Quart. Journ. Micr. Sci., xl. (1897) pp. 77-99 (1 pi. and 3 figs.), t Biol. Centralbl., xvii. (1897) pp. 465-85, 513-30. ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 393 enters through the wall of the thread and of the capsule, hut there is some other cause of the actual shooting out of the thread. The author adheres to his theory that the sub-epithelial nerve-plexus inhibits the expulsion, which he regards as reflex. He concludes less optimistically than he did in his summary of ten years ago, when he spoke of our knowledge of the functioning of the stinging cells as satisfactorily complete. Aliciidae.* — Mr. J. E. Duerden recalls his study of Alicia costse Pane, and Cystiactis tuberculosa Quoy and Gaim., which showed the necessity of separating them from the Bunodidae, and the erection of a new family Aliciidae. He has since been fortunate in obtaining an authentic speci- men of A. mirabilis (the type of the genus) from Mr. J. Y. Johnson, who founded the genus in 1861. He also describes a new species of Bunodeojpsis, B. antilliensis, and compares it with the type B. strumosa. To Alicia, Cystiactis , and Bunodeojpsis, the genus Thaumactis Fowler has also to be added. The family diagnosis is as follows : — Hexactinece, with a large flat contractile base. Tentacles simple, subulate, and entacmaeous. Column with simple or compound hollow outgrowths or vesicles over more or less of its surface, arranged mostly in vertical rows. No cinclides. Sphincter muscles endodermal and diffuse, variable in amount of development. Perfect mesenteries few or numerous. No acontia. Porifera. Position of Sponges in the Animal Kingdom.f — Mr. E. A. Minchin has a learned article on this difficult problem. He states the case for Sponges, as (1) Protozoa, (2) Metazoa, and (3) neither. The majority are in favour of sponges being Metazoa ; but then the alternatives crop up — are they Coelentera, or do they represent a distinct phylum ? The four points of primary importance in the discussion of the affinities of Sponges are : — (a) The unfailing possession of collar-cells, and their great resemblance to Choanoflagellata ; ( b ) the reproduction by ova and spermatozoa ; (c) the formation of two germ-layers by pro- cesses not specially characteristic of sponges, and the possession of a larva very similar to the coelenterate planula ; and (d) the reversion of the germ-layers at metamorphosis — a fact which is quite subversive of the coelenterate theory. We have but two theories, the author says, to choose between : — either to regard sponges, with Biitschli, Sollas, and Delage, as descended from choanoflagellate ancestors independently of the Metazoa ; or to regard them, with Maas and, apparently, Balfour, as true Metazoa, whose two primary germ-layers have become reversed in position in the adults. The author inclines to the second alternative, but says we should be cautious in pinning our faith to either. Perhaps there is yet another. Hexactinellids with Discoctasters.J — Prof. J. Ijima gives a general description of the structure of the Hexactinellida which have those strongly modified discohexasters which F. E. Schulze called discoct- asters. This peculiar kind of spicule has hitherto been known to occur * Arm. Nat. Hist., xx. (1897) pp. 1-15 (1 pi.). f Science Progress, i. (1897) pp. 426-60. X Annot. Zool. Japon., i. (1897) pp. 43-59. 394 SUMMARY OF CURRENT RESEARCHES RELATING TO in four species of Kossellidae, viz. Acantliasciis cactus F. E. S., Rhabdo- calyptus mollis F. E. S., Bh. Roeperi F. E. S., and Bh. Dowlingi L. M. Lambe. To this list Prof. Ijima adds two new species of the last- named genus, viz. Bh. capillatus sp. n., Bh. victor sp. n., and three others belonging to a new genus Staurocalyptus . In this he includes Schulze’s Bh. Roeperi , Lambe’s Bh. Dowlingi , and his own new forms which he names St. heteractinus , St. glaber , and St. pleorhaphides. The diagnosis of the new genus reads — “ Discoctasterophorous Rossellids with pentactin hypodermalia, the para tangential rays of which never possess hook-like prongs, but are either smooth or minutely and uni- formly rough.” Protozoa. Influence of Various Solutions upon Infusoria.* — Mr. A. Yasuda has experimented as to the effects of placiDg Infusorians ( Colpidium , Chilomonas3 Euglena , Paramoecium, &c.) in solutions of milk-sugar, cane- sugar, grape-sugar, glycerin, and common salt. The action depends more upon the chemical nature of the substance than upon its concentra- tion ; for isotonic solutions of the five substances mentioned above do not produce corresponding effects. In solutions of higher concentra- tion a contraction of the Infusorians takes place, which disappears after some hours, when tbe organisms begin to accommodate themselves to the new media. Higher concentration of the medium retards first the multiplication, and then the movement of the organisms. In sugar- solutions of higher concentration, some Infusoria seem to increase in size only till a certain limit is reached. The vacuoles or the corpuscles in the cells increase in diameter as the concentration of the medium becomes stronger. The more the concentration of the medium increases, the more rounded become the organisms. Biflagellata.f — Dr. W. H. Dallinger replies indirectly to B. France’s criticism of the well-known studies which he and the late Dr. Drysdale made on biflagellate organisms. The point seems clear that the investi- gators refrained from nomenclature or classification, but observed (first independently and then jointly) seven definite living micro-organisms passing through a continuous series of cyclic changes. Whether the “ biflagellate ” of Dallinger and Drysdale is identical with the Polytoma of France’s paper remains uncertain, and therefore cannot form a basis of criticism. Dr. Dallinger adheres to the conclusions reached with great care and patience many years ago, and questions the competence and suitability of France’s methods as modes of criticism of the joint work of Dr. Drysdale and himself. Parasitic Flagellata of Termites.^ — Prof. B. Grassi and Dr. A. Sandias described in 1890 the parasitic Protozoa in Termites. An edited translation is now available. Of Lophomonadidse, there are three — Joenia annectens g. et sp. Grassi (in Calotermes lucifugus), Tricho- nympha agilis Leidy (in Termes lucifugus), and Microjoenia hexamitoides g. et sp. Grassi = Leidy’s immature Trichonympha (in T. lucifugus) ; of Cercomonadidae, there are two — Monocercomonas termitis Grassi (in * Annot. Zool. Japon., i. (1897) pp. 23-9. See Bot. Mag. Tokyo, xi. (1897). t Biol. Centralbl., xvii. (1897) pp. 305-11 (4 figs.). j Quart. Journ. Micr. Sci., xl. (1897) pp. 43-54 (1 pi. in vol. xxxix.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 395 T. flavicollis and T. lucifugus), and Dinenympha gracilis Leidy (emend.) ; probably = Pyrsomympha vertens Leidy ( pro parte), in T. lucifugus ; of Pyrsonymphidae, there are two — Pyrsonympha flagellata Grassi (in T. lucifugus ), and Holomastigotes elongatum g. et sp. Grassi in the same. It is remarkable that none of these were seen encysted or clearly in process of reproduction. They all ingest solid particles of wood, except the last named ; and it is the only one without the rods and rodlets which probably serve as an endoskeleton for the support of the cell and pro- tection of the nucleus. These parasites may aid in digestion ; they die or disappear in individuals fed with saliva ; and it is only when they disappear that the gonads of the Termite mature. Regeneration of the Micronucleus in Ciliata.*— M. Felix Le Dantec has experimented with portions of ciliated Infusorians which contained the macronucleus or a fragment thereof, but no trace of micronucleus. He does not regard his results as quite conclusive ; but, in some cases at least, it seems as if a new micronucleus could be formed within artificially produced pigments (merozoites) which con- tained no trace of the original micronucleus. Experimental Study of Coccidia/f — M. Louis Leger has made some experiments in order to test his theory that the primitive Coccidian sporozoite has not a dimorphic development resulting on the one hand in Eimeria and on the other hand in Coccidium ; but that it exhibits a continuous cycle leading to the formation of Cystozoites (sporozoite of Eimeria according to other authors), and continuing into sporocysts (or cysts with lasting spores). Starting from the fact that the adults of Scolopendra cingulata usually contain a polysporous Coccidian (Adelea dimidiata Schneider) and numerous groups of Eimerian sporozoites, while the young are but rarely infested, Leger took two young forms which seemed to bo free from parasites, and made them swallow cysts of Adelea in a state of perfect maturity. After 25 days one was sacrificed, and showed a mid- gut crowded with Eimerian sporozoites free or in groups ; the second specimen, killed twenty days afterwards, showed young forms of Adelea already furnished with a protective sheath. The experiments show the specific unity of Eimeria and Adelea. They also confirm the view that the primitive sporozoite, issuing from a cyst of Adelea, gives rise first to Eimerian cysts whose sporozoites afterwards become the cysts of Adelea or sporocysts. The results also explain why Eimeria should be abundant in Myriopods in spring, and Adelea in autumn ; they are stages, not different forms. The sporozoite of Coccidia probably corresponds to the Gregarine sporoblast, and the coccidian sporocyst to the octozoic spore of Grega- rines.. Perhaps the difference in the cycles is due to the absence°of sufficient nutritive material in the Eimerian cyst of Coccidia, whereas in Gregarines the cyst is abundantly furnished with reserves which are amply sufficient for the further development of the sporoblasts. New Type of Sporozoa-J— MM. F. Mesnil and E. Marchoux describe Coelosporidium chydoricola g. et sp. n., which they regard as intermediate * Comptes Rendus, exxv. (1897) pp. 51-2. f Tom. cit., pp. 329-30. X Tom. cit., pp. 323-6 (6 figs.). 396 SUMMARY OF CURRENT RESEARCHES RELATING TO between tbe Sarcosporidia and Amoebidium Cienkowsky. It is an internal parasite of Cliydorus sphsericus O. F. Muller — a Crustacean belonging to tbe family Lynceidue and order Cladooera — which occurs in the ponds in the woods of Bellevue, near Paris. One part of the life-history takes place in the cavity of the body, where rounded young forms increase in size, become ovoid and almost crescent-shaped, show great nuclear multi- plication, and acquire a thick and resistant envelope. The division of the protoplasm is effected slowly, but the result is a cyst with numerous ovoid or spindle-shaped corpuscles, which doubtless correspond to the reniform bodies of the Sarcosporidia. They probably infect other indi- viduals after tbe death of their host. Within the tissue, however, on the dorsal surface of the gut, another phase of the history has its seat. Elongated cylindrical forms occur, with fewer and larger nuclei than the free forms, and without their refractive and fatty globules. They probably increase the infection within the individual host. As this new type shows a close resemblance to Amoebidium, an ecto- parasite of freshwater Crustacea, the authors propose to include the latter along with Coelosporidium in a new sub-order of Sarcosporidia. They suggest that Amoebidium is an exceedingly primitive form, and they point out the interest of the double developmental cycle in their new type. Dimorphism seems to be very general in Sporozoa. Two biological facts are of much interest, (a) All the infected Crustaceans were non-reproductive ; there seemed to be parasitic castra- tion ; (b) the parasite is confined to this particular species. Gregarines of the Cricket.* — L. Cuenot has found two new species of Diplocystis (D. minor and D. major) and a new Clepsidrina (O. gryl- lorum) in Gryllus domesticus. He showed experimentally that crickets are infected by eating other crickets with ripe spores ; the sporozoites take up their position in the epithelium of the mid-gut, and the cycle recommences. The author notices the “ positive cytotropism ” expressed in the association of the Gregarines in pairs, and what seems like a micronucleus. When two individuals unite before sporulation, the membranes persist on to an advanced stage, so that there cannot be any karyogamic fertilisation. The nuclear phenomena of sporulation include (1) degeneration of the macronucleus, which loses its membrane and nuclear sap, while the central karyosome slowly dissolves in the cytoplasm; and (2) the division of the micronucleus (in a manner midway between the mitotic and the amitotic fashion) to form the archispores. Double Use of the Name Diplocystis. j — B. Cuenot notes that in Schaudinn’s Heliozoa in the new ‘ Thierreich,’ a genus is recorded as Diplocystis Penard (1890). The name was, however, applied in 1887 by Kiinstler to a Gregarine found in the body-cavity of Periplaneta americana. Only one species, D. Schneider i, was noted ; and as it was not re-observed, the validity of the genus has been doubted. But Cuenot has recently found two coelomic parasites in Gryllus domesticus which evidently belong to Kiinstler’s genus. Therefore Diplocystis Penard must be changed. * Comptes Rendus, cxxv. (1897) pp. 52-4. t Zool. Anzeig., xx. (1897) pp. 209-10. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 397 Life-History of Coccidia.* — Dr. P. L. Simoncl lias studied Coccidium oviforme, Coccidium ( Karyophagus ) Scdamandrse. and C. proprium. The facts seem at first to point to a polymorphism rather than a dimorphism ; but all the forms of the asporulate state are simply phases of one process, polymorphic in relation to particular conditions, and contrasted, not with one another, but only with the sporulating state. The latter, especially in its final resistant stage, exhibits a fixity of characters which makes it the essential and typical mode of reproduction. The two modes are morphologically and physiologically distinct, like fission and the forma- tion of endospores in Bacteria ; the one is a rapid temporary multiplica- tion in a suitable environment ; the other, which probably requires an antecedent sexual process, secures the rejuvenescence and perpetuity of the race. Those forms which seem to have but one mode of multiplica- tion require further investigation. All the asporulate forms may be considered as one individual or generation which undergoes repeated fragmentation ; the true specific reproduction is confined to the sporulate condition. The new facts shed light upon the life-history of the parasite of paludism discovered by Laveran, and corroborate^Metschnikoff’s indica- tion of the affinities between this Hasmatozoon and Coccidia. The motile stage of Coccidium explains the flagellate bodies of the paludism parasite and of Polymitus in birds. In short, the life-histories of Coccidia and Haematozoa should be carefully correlated. New Myxosporidium.t — M. L. Leger describes a Myxosporidium which affects the larvae of Simulium ornatum Meig. It inhabits the general body-cavity, the intestinal tract being quite free. It occurs in masses, which often have the appearance of thin-walled cysts. Micro- scopic examination of these masses shows them to be composed of a pro- digious number of spores which are ovoid ’and refracting, and have a large vacuole at the expanded end. Under the influence of iodine, a filament, twenty times as long as the spore itself, shoots out from the pointed end, a fact which indicates that these parasites belong to the family ‘ Glugeidse . The spores are of two kinds, small (4-5 yd) and large (8 y). Some sacs contain only microspores, and then usually in little groups of eight, while others have only macrospores. * Ann. Inst. Pasteur, xi. (1897) pp. 545-81 (2 pis.), f Comptes Rendus, exxv. (1897) pp. 260-2. 398 SUMMARY OF CURRENT RESEARCHES RELATING TO BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-structure and Protoplasm. Spermatogenesis in Lilium Martagon.* — Miss E. Sargant supple- ments her previous observations on this subject by a detailed account of the processes which take place in the nuclear divisions of the pollen- grain. They are strictly parallel to the corresponding stages in oogenesis. The first division of the pollen-mother-cell nucleus is similar in every detail to that of the primary embryo-sac nucleus, and may be termed heterotype ; the three later divisions are homotype. When the pollen-mother-cell is differentiated, its nucleus is built up of 24 chromosomes. The whole interval between the complete differen- tiation of the pollen-mother-cell and the formation of the young pollen- grains within it may conveniently be divided into four periods, viz. : — (1) The nucleus of the pollen-mother-cell grows larger and alters in structure, finally assuming the well-known spirem-condition ; (2) Twelve chromosomes are formed from the spirem- ribbon, and lie loose in the nuclear cavity; (3) The first karyokinesis of the pollen-mother-cell nucleus separates the two halves of each chromosome ; cell-division follows this nuclear division ; (4) The second karyokinesis divides the nucleus of each daughter-cell into two, and is followed by a correspond- ing cell-division. The various stages of these processes are described in great detail. The four nuclear divisions included in the spermatogenetic series of Lilium Martagon present one important characteristic in common with each other, with the three oogenetic divisions, and with ordinary vege- tative division. In each of these cases the effect of the whole process of karyokinesis is to divide each parent chromosome into a pair of daughter- chromosomes by longitudinal fission, and to build up duplicate daughter- nuclei from the duplicate sets of daughter-chromosomes thus formed.! Honeycomb Structure of Vegetable Substances.! — Herr K. Purie- witsch brings forward evidence in opposition to Biitschli’s theory of the honeycomb structure of protoplasm. In a large number of cases ex- amined by him — starch-grains of arrowroot, potato, and wheat, cotton- fibres, bast-fibres of Nerium Oleander, stone-cells of Podocarpus salicifolia, &c. — he found the structure to agree more with Nageli’s micellar theory than with Butschli’s. An argument against Biitschli’s theory is that if vegetable structures consisted of a meshwork containing fluid, they would present different optical properties when dry to what they do when moist, which does not appear to be the case. * Ann. Bot., xi. (1897) pp. 187-224 (2 pis.). Cf. this Journal, ante , p. 213. t The processes of fixing, imbedding, and staining employed by Miss Sargant will be found at p. 445. ( X Ber. Deutsch Bot. Gesell., xv. (1897) pp. 239-47. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 399 Streaming of Protoplasm in Pollen-Grains.* — According to Miss H. B. Potter, many pollen-grains — those of the foxglove are a good example — are convenient illustrations of the streaming of protoplasm. The granules of protoplasm move in opposite streams side by side, turning at the lower end of the tube and inside the grain. The rate of motion may be calculated at 1 mm. in 1J-2 minutes. The pollen-tube itself was observed to grow at an average rate of 0 * 1 mm. per hour. Cell-Membrane.f — Prof. J. Reynolds Green reviews the present state of our knowledge of the constitution and chemical properties of the cell-wall. It may be stated as certain that the cell-wall is originally far from homogeneous ; and that, while cellulose enters very prominently into its composition, there are present in it a number of other substances which have hitherto been somewhat loosely described under the names of pectose, pectine, and compounds of pectic acid. The modifications of cell-wall which give rise to gums and mucilages, all of which are pro- bably very complex, may well be derived from these, and not from the cellulose constituents. These compounds may be arranged in two series, neutral and feebly acid. Of the former the most important are pectose and pectine ; of the latter, pectic and metapectic acids. There is a marked difference between cellulose and pectic substances in their be- haviour towards staining reagents. Cellulose acts as a feeble base, and takes up acid stains, especially those which contain nitrogen. Pectic compounds, on the other hand, act as acids, and require basic stains. Haamatoxylin, methylene-blue, vesuvian-brown, and quinolin-blue, stain the pectic constituents of the wall, not the cellulose. Inclusions in the Living Cell-Wall. J — Herr C. Muller finds, in the walls of certain cells in the root of Spiraea Filipendula , crystal-like masses, which give none of the reactions of calcium oxalate or calcium carbonate, but, on the contrary, those of cellulose. He concludes that these crystalline masses are cellulose, and believes their occurrence to be very general. (2) Other Cell-contents (including Secretions). Red Pigment of Flowering-Plants. § — Mr. F. W. Keeble gives a resume of the observations and theories of various writers on the red pigments of the floral organs known under the general term anthocyan, and of their functions. He dismisses, as unsupported by sufficient evi- dence, the theory that the red pigment acts as a screen to the chlorophyll, preventing its destruction by the action of the sun. On the other hand, lie strongly supports Stahl’s view, that its main function is the absorp- tion of heat. Hence its very frequent presence in the perianth, anthers, or styles of anemophilous trees and shrubs, as in the poplar, hazel, Itumex, and Poterium . In the case of the red stigmas of the hazel, it may materially accelerate the growth of the pollen-tube towards the ovary. Structure of Starch-Grains. || — Herr W. Rothert criticises in several points Meyer’s views as to the structure of starch-grains, and the nature * Nature, lvi. (1897) p. 248. t Science Progress, i. (1897) pp. 344-64. X Ber. Deutscli. Pharm. Gesell., 1897, p. 11. See Bot. Gazette, xxiii. (1897) p. 388. § Science Progress, i. (1897) pp. 406-23. Cf. this Journal, 1896, p. 543. || Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 231-9. Cf. this Journal, 1896, p. 80. 1897 2 f 400 SUMMARY OF CURRENT RESEARCHES RELATING TO of tlie phenomena connected with their swelling. He regards as unne- cessary the use of the terms a-amylose and /3-amylose, as proposed by Meyer, the former being practically identical with the farinose, the latter with the granulose of earlier writers. The term amylose might then be retained for the substance resulting from the conversion of granulose into paste. He dissents further from Meyer’s theory as to the mode in which water penetrates into the substance of the starch- grain. The author does not agree with Meyer as to the difference between ordinary swelling and conversion into paste ; both consist in an absorption of water into the substance of the starch ; but while, when starch dissolves in cold water, the unchanged granulose absorbs but little water, and preserves its solid consistence and its crystalline structure ; when converted into paste it passes over into a different substance which absorbs much more water, and forms, in the swollen condition, dimorphic mucilaginous drops. Swelling is simply a special case of solution, in which a fluid substance is dissolved in a solid substance. Bodies capable of swelling are those which are able to dissolve certain fluids. The author does not consider that Meyer brings forward satisfactory evidence of his statements that every starch-grain is completely and constantly surrounded by the substance of its chromatophore, and that the cliroma- tophore-envelope is also the sole seat of the formation of diastase. In all probability it is formed in the cytoplasm. Soluble Starch.* — M. P. Guerin finds a substance possessed of the chemical properties of starch dissolved in the cell-sap in Cola acuminata and C. Ballayi, belonging to the Sterculiacese. The cells in which this substance occurs are almost exclusively epidermal; but it has been found also in the mucilage canals. In the lower epiderm of the leaves, starch-grains of the ordinary kind are present in the same cells as the soluble starch. Aromatic Principles in Leaves.f — M. G. Jacquemin finds that with plants which bear fragrant or sapid fruits — as the apple, pear, raspberry — if the leaves are placed in a saccharine fluid with Saccharomyces or some other enzyme, the fluid will acquire the flavour and odour of the fruit, and the alcohol obtained by distillation from this liquid will possess the corresponding bouquet. Active Principles of the Aroidese.J — Mdlle. J. Chauliaguet and MM. A. Hebert and F. Heim have investigated the nature of the poison- ous principles in several species of Aroidese, chiefly Arum maculatum, A. italicum, and Arisarum vulgar e. They find the constant presence of a glucosidc, with the characters of a saponin, in the underground organs and the leaves. The alkaloid was extracted, and was found to correspond in all its properties with the conicin of the hemlock, though somewhat less active. A similar volatile alkaloid exists in the tubercles of Cala- dium bulbosum and Amorjdiophallus Bivieri. The author was unable to confirm the occurrence of hydrocyanic acid, affirmed by previous writers. Latex and its Function. § — From the fact that some of the chief constituents of latex are starch, proteids, and sugar, and that the pro- * Bull. Soc. Bot. France, xliv. (1897) pp. 91-5. t Comptes Rendus, cxxv. (1897) pp. 114-6. j Op. cit., cxxiv. pp. 1368-70. § Ann. of Bot., xi. (1897) pp. 334-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 401 teids are typical circulatory forms, and that the quantity of sugar varies with the plant’s assimilation, Mr. R. H. Biffen argues that one function of latex must be to transport reserve-materials in the plant. The blind endings of the laticiferous system are generally connected with the pali- sade-cells. The result is given of determinations of the amount of sugar i^resent at different periods of the day in several species of Euphorbia. Caroubinase, a new Hydrolytic Enzyme.* * * § — M. J. Effront finds, in the seeds of the carob, Ceratonia siliqua , a hitherto undescribed diastase formed during germination, to which he gives the name caroubinase. It is produced especially after the seedling has developed a considerable amount of chlorophyll, and possesses strong liquefying and saccharifying properties. Doubling of the Fundamental Band of Chlorophyll.-)- — According to M. A. Etard, the number of the bands of chlorophyll and the wave- length of their mean axis may be accurately counted by the method of successive dilutions, and may serve to characterise the exact kind of chlorophyll. The diversity of the chlorophylls is shown by the wave- length of the axis of their bands either already existing or incited by the action of reagents. The fundamental band of the chlorophylls is not always uniformly dark ; it may be double or triple. The special charac- teristics are described in detail of “ loliophyll,” the chlorophyll derived from Lolium perenne and other grasses. (3) Structure of Tissues. Stem of Compositse.J — Herr F. E. Ahlfvengren has examined the anatomical structure of the stem of 230 species belonging to 125 genera of Composite. He finds no single character belonging to the entire group. The following are some of the more interesting points. The sieve-plates are horizontal, or only slightly oblique ; there are none on the side- walls. There is always an intraxylary cambiform. The Cicho- riaceee have invariably septated latex-tubes ; most of the Tubifloraa have oil-canals. In the Cynarese oil-canals occur in those genera and species which have no latex-idioblasts in the vascular bundles. The quantities of starch and inulin are in inverse proportion to one another in the stem of Composite ; the younger parts are richer in starch, the older parts in inulin. Starch appears to be transformed into inulin during its migra- tion. Stem of Cuscuta.§ — M. M. Cornu finds several peculiarities in the stem of a species of Cuscuta from Turkestan, C. Lehmanniana , parasitic on j Robinia pseud-acacia. These are as follows : — The formation of secondary elements in the fibro-vascular bundles, and in the inter- fascicular zones. The nature of these elements, especially of the tracheids, which vary in their origin according to their position. The deposition of a special substance, of the nature of cellulose, in the cells which border the primary or secondary vascular elements and the * Comptes Rendus, cxxv. (1897) pp. 116-8. f Op. cit., cxxiv. (1897) pp. 1351-4. Cf. this Journal, ante, p. 48. t (Swedish) Lund, 1896, 86 pp. and 28 figs. See Bot. Centralbl., lxx. (1897) p. 208. § Bull. Soc. Bot. France, xliii. (1897) pp. 699-720 (2 pis. and 2 fi<”s.). 2 f 2 402 SUMMARY OF CURRENT RESEARCHES RELATING TO internal lacuna. Tlie increase, either in diameter or in thickness, of certain elements near the haustoria, and a considerable increase in the size of the nuclei. The large size and the nature of the sieve-tubes, which vary in form, and which recall the general type in woody plants. The large size and the number of the laticiferous tubes, which are very distinct from the pericyclic fibres. Structure of Piperaceae.* * * § — M. A. de Candolle calls attention to several interesting points connected with the structure of the stem of climbing plants belonging to the Piperaceae, especially to the large size of the vessels compared to those of allied species which are not climbers. Polystely in Primula. f — Mr. D. T. G wynne Vaughan finds remark- able variations in structure as to polystely within the same species in the genus Primula , even in different regions of one and the same plant. In P. japonica, obtusifolia, denliculata , and involucrata , the normal stem- structure of 2-4 anastomosing steles is by no means universal ; all the steles are very often defective or imperfect. In P. japonica and denti- culata certain structures were invariably found in the petiole which are similar in all essential respects to normal and perfect steles. Lenticels of Monocotyledons.^ — Herr A. Weisse describes the oc- currence of true lenticels in a variety of plants belonging to different orders of Monocotyledons : — in the aerial roots of Aroideae ( Monstera deliciosa , Philodendron , Anthurium) ; in arborescent Liliaceae ( Aloe, Bracsena, Cordyline) ; and in the rhizome of Iris germanica . In the Pandanaceae and Palmae, on the other hand, no true lenticels could be detected, either in the stem or in the root. Neither is any true periderm- found in these plants. In the aerophilous roots of the Pandanaceae, the peculiar pneumathodes assume the function of lenticels. Resinocysts.§ — Herr M. Schoennett describes under this name bodies of a very peculiar nature found in the stem, leaf-stalk, and lamina of a species of Begonia . They are usually hemispherical structures, in close apposition to the cell-wall, always in pairs, one on each side of the wall. They have a characteristic stellate appearance. They are always found in the fundamental parenchyme, in immediate proximity to the primary vascular-bundle system. They vary in breadth between 8 and 12 /a, and in length between 12 and 20 /x. They are attached to the cell- wall by a very short stalk. With regard to their chemical constitution, they are undoubtedly of a resin-acid nature. They are completely solu- ble in alcohol, and take up stains very readily. Other chemical reactions are given in detail. The stalk consists of pure cellulose. As regards their function, they must be regarded as in the main products of excre- tion, though the author is of opinion that they may in certain cases take part in the formation of food-materials for the plant. They have not, at present, been detected elsewhere in the vegetable kingdom. * Ann. Sci. Phys. et Nat., iii. (1897) pp. 514-5. t Ann. of Bot., xi. (1897) pp. 307-26 (1 pi.). % Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 303-20 (1 pi.). § Kosmos, xviii. pp. 382-98 (2 figs.) (Polish). See Bot. Centralbl., lxx. (1897) p. 50. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 403 Abnormal Formation of Resin-Ducts.* * * § — Dr. A. P. Anderson de- scribes the conditions under which resin-ducts are formed abnormally in Conifers. This may be due either to the effects of frost, or to the attacks of AEcidium elcitinum , the fungus which produces “ witch-broom,” or to infection by other fungi, such as Agaricus melleus, Phoma abietina, and Pestalozzia Hartigii. He regards the resin as in all cases an excretory product, haying no further use in the metabolism of the plant. When- ever resin-reservoirs are found in the wood of Abies pectinata , they are a sure indication of some pathological condition existing in the plant. Anatomy of the (Enotherege and Haloragese.f — A study of the anatomical structure of the stem and leaves leads M. P. Parmentier to divide tho order Onagraceae into the two families (Enotheraceae and Haloragaceae — the former being again subdivided into the Ludwigieae and the (Enotliereae ; the latter into the Halorageae and the Gunnereae. Details are given of the histology of each genus. Gayophytum and Glarkia are sunk in (Enothera , and Jussisea in Lndwigia ; while Scliizo- carya is separated generically from Gaura. There are distinct modes of crystallisation of the calcium oxalate characteristic of the two fami- lies (Enotheraceae and Haloragaceae. Ludwigia possesses both kinds. Another difference between the two families is in the nature of the hairs. The root of Gunnera presents a remarkable peculiarity in having secondary vessels enclosed in its pith. Stomates occur on both surfaces of the leaf, even in the aquatic species. (4) Structure of Org-ans. Relationship between the Structure and Function of Organs*! — Herr Rosen gives a brief resume of the facts respecting the degeneration or other modification of the floral and vegetative organs of plants, and their consequent adaptation to special functions. Position of Dorsiventral Organs.§ — From an examination of the forces which determine the position of leaves in a number of plants, Mr. R. N. Day derives the following conclusions : — The prevalence of an epinastic or hyponastic condition in any organ is due entirely to inde- pendent causes, and may be said to be spontaneous. In many plants leaves are epinastic in an earlier- and hyponastic in a later period of growth, or vice versa. It is entirely independent of light ; there is no such thing as photo-epinasty. All dorsiventral leaves are diaheliotropic. They may be either diageotropic or apogeotropic. The position of the organ is determined by the relative intensity of the geotropic and the trophic forces acting upon it. Development of the Flower. || — Prof. L. J. Celakovsky traces the phylogenetic development of the flower of Phanerogams from the sporo- phyll of the Lycopodiaceae and Equisetacese. The lowest stage is seen in the flower of the Gymnosperms, — naked in the Cycadeae and Coniferae, * Forst.-naturw. Zeitschr., 1896, 38 pp. and 7 figs. See Bot. Gazette, xxiii. (1897) p. 292. f Ann. Sci. Nat. (Bot.), iii. (1896) pp. 63-149 (6 pis.). t J-B. Schles. Gesell. vaterl. Cultur (No. 71); Bot. Sect., pp. 33-42. See Bot. Centralbl., lxx. (1897) p. 125. § Minnesota Bot. Studies, 1897, pp. 743-52 (1 pi.). H S.B. K. Bohm. Gesell. Wiss., 1896, 91 pp. and 4 figs. 404 SUMMARY OF CURRENT RESEARCHES RELATING TO but provided with a perianth in the Gnetacese. The absence of a perianth in the two first-named orders is not the result of degeneration. The “ cones ” of the Araucariese are not flowers, but spike-like inflorescences. The separation of the sexes is, on the other hand, a phenomenon of reduc- tion, the oldest forms having hermaphrodite flowers. The Gnetacese exhibit also reduction of the gynaeceum to a single carpel, and also in the number of the stamens. The Araucarieae have always only a single integument ; the outer integument of the Taxaceae is homologous to the carpid of the Araucarieas. Doubling of the stamens occurs for the first time in the male flowers of the Gnetaceae. We get in the Gymno- sperms the first manifestation of the spiral arrangement of the phyl- lomes, so common in Angiosperms. In the Monocotyledones we have a further advance in the differentia- tion of the perianth into calyx and corolla ; both whorls may be sepaloid, the outer sepaloid and the inner petaloid, or bctli petaloid. They cannot be regarded as metamorphosed stamens (except in Halophila). The old- est forms are unquestionably hermaphrodite. The typical flower of the Cyperaceae has 6 perianth-bristles, 6 stamens, and a 2-3-merous whorl of carpids ( Lejpidosperma ), the smaller number in other genera being the result of reduction. The Gramineae also exhibit all stages of reduction in the gynasceum from numerous carpels ( Ochlandta ) to 3 ( Strepto - chdeta), and 1 with a single stigma ( Nardus ) ; a corresponding reduc- tion taking place also in the number of the stamens. Structure of Pollen-Grains.* — Herr J. Balazs describes the form and structure of the pollen-grains of a number of plants belonging to the Angiosperms. He classifies them under 4 types, viz. : — (1) renifornT; (2) ellipsoidal ; (3) spherical ; (4) ellipsoidal, abruptly rounded at both ends. Structure of the Fruit in Ranunculaceae.t — Herr K. M. Wiegand classes the genera of Banunculaceae into 8 groups according to the struc- ture of the fruit, a classification which he believes also to represent their genetic affinity. The form and size of the embryo, the nature of the endosperm, the histology of the two integuments of the seed, and the form and structure of the pericarp, are described in detail for each genus. The author believes that the achene represents a reduced capsule (follicle), resulting either from contraction of the upper part and reduction of the ovules to one, as in Ranunculus, or from expansion of the ovary below with almost complete closing of the upper part, as in Clematis , Anemone, and other genera with pendent seeds. Micropyle of the Seed in Leguminosae.ij: — M. H. Coupin has studied the structure and development of the micropyle in a number of species of Leguminosae. He classifies the various forms under 4 types, viz. : — (1) a cup ( Vida Faba ) ; (2) a canal ( Cytisus ) ; (3) a closed cavity ( Lwpi - nus ) ; (4) indistinct ( Arachis ). In all cases the micropyle undergoes considerable changes during the development of the ovule into a seed. Except in the case of Abrus, the epiderm of the micropylar canal has * ‘Ueb. d. Pollen,’ Kolozsvar, 1896, 61 pp. See Bot. Centralbl., lxx. (1897) p. 156. t Proc. Amer. Micr. Soc., 1894, pp. 69-100 (8 pis.). See Bot. Centralbl., lxx. (1897) p. 211. X Rev. Gen. de Bot. (Bonnier), ix. (1897) pp. 175-80 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 405 entirely disappeared in the ripe seed, and the cavity is surrounded immediately by the parenchymatous cells, thus communicating directly with the intercellular spaces of the parenchyme. The canal is usually obliterated in its lower portion. Crest of Seeds.* * * § — Mr. C. Robertson suggests that the purpose of the crest of many seeds, where it is not sufficiently large to add to their attractiveness to frugivorous birds or other animals, is to furnish a handle by which they can be carried away by ants, and their dissemina- tion thus secured. Domatia. I — Mr. A. C. Hamilton gives an account of the occurrence of these structures in a number of Australian and other plants. Their most common form is that of a tuft of hairs in the axil of a vein on the under surface of the leaf, with which is connected an opening through the epiderm. The author classifies them under 5 heads, viz. : — (1) Circular lenticular cavities on the under side of the leaf, each with a small open- ing and a thickened rim ; (2) pouches formed by a widening of the principal and lateral veins at the axils, the space being filled in with tissue so as to form a triangular pouch or pocket ; (3) depressions or hollows formed by a thinning of the leaf-substance at the axils ; (4) bunches of hairs in the axils of the principal and secondary veins ; (5) denser bunches of hairs at the vein-axils of hairy leaves. The author gives the number of species in which domatia have been observed by himself or others as nearly 300, about one-half of these belonging to two natural orders, Rubiaceae (107) and Tiliaceae (40). The domatia are generally, but not always, inhabited by mites ; but the author does not accept Lundstrom’s view that their main object is connected with com- mensalism. He considers it more probable that their primary function is concerned with the absorption of gas, vapour, or water. Morphology of Aquatic Plants.^ — The conclusion arrived at by Goebel that the narrow ligulate leaves of Sagittaria sagittsefolia are the results of a reversion of the mature sagittate leaves to an earlier and simpler type, is applied by Herr W. Wachter to other aquatic plants. In S. natans there are two forms of leaf ; the earlier ones are ligulate, and (in contrast to those of S. sagittsefolia) are persistent, the mature leaves having an elliptical lamina. These merely represent different forms of the same leaf, the difference being apparently due to conditions of light. The results were not so decisive with S. chinensis, Eichliornia azurea, or Hydrocleis nymphoides. A detailed description is given of the anomalous Weddellina squamu - losa , belonging to the Podostemaceae. Leaves of Aquatic Gentianace8e.§ — M. E. Perrot describes a pecu- liarity in the structure of the leaves of certain species of Villarsia and Limnanthemum, In L. nymphdeoides the under surface of the floating leaves exhibits a number of brown spots, formed of cells with straight somewhat thickened walls, containing a brown pigment of the nature of tannin, and numerous grains of chlorophyll. At these spots the epi- * Bot. Gazette, xxiii. (1897) pp. 288-9. t Proc. Linn. Soc. N. S. Wales, xxi. (1896) pp. 758-92 (1 pi.). Cf. this Journal, 1888, p. 87. % Flora, lxxxiii. (1897) pp. 367-97 (21 figs.). § Journ. de Bot. (Morot), xi. (1897) pp. 195-201 (4 figs.). 406 SUMMARY OF CURRENT RESEARCHES RELATING TO dermal cells are much smaller than elsewhere, and the subjacent layers are rich in chlorophyll. The normal epidermal cells are thin-wa'lled, and are charged with a violet pigment. The spots with the small thick-walled cells become “ domatia ” for epiphytic algae and aquatic animals. ; Metamorphosed Buds of Lilium bulbiferum.* * * § — Herr H. Hesselman describes a very remarkable development of the buds of Lilium bulbiferum , in which the scales are transformed into floral leaves — perianth-leaves and stamens. In some cases the former completely assumed the form and colour of ordinary perianth-leaves, while the latter even produced pollen-grains capable of germination. The pliyllotaxis of the metamor- phosed bulbils was always spiral. Pellucid Dots in Hypericum.f — Mr. T. Meehan calls attention to the occurrence of two kinds of dots on the leaves and other organs of many species of Hypericum , black and pellucid, the abundance of each kind being often in inverse proportion to that of the other. He regards the pellucid dots as “ the initial steps taken by the plant in the formation of veinlets and veins.” Honey-Glands in Plants.^ — Mr. T. Meehan describes the nectar- glands in a Nepalese orchid, Cymbidium aloeifolium, in which the exuda- tion of saccharine matter appears to be absolutely useless to the individual plant. In Phlox paniculata also (p. 179), the most abundant flow of nectar takes place long after pollination has been effected, the stigma appearing to be self-pollinated. Glands of Tozzia and Lathrgea.§— On the leaves and leaf-scales of Tozzia alpinci and Lathreea squamaria, Prof. K. Goebel finds two kinds of gland, peltate and capitate. As is the case with other Rhinantheae, these plants possess the property of exuding water from the leaves ; and the glands — certainly the peltate, and probably also the capitate kind — appear to be the organs by which this exudation is effected. Spines of the Aurantiaceae.|| — From observations made on the orange, Mr. T. Meehan concludes that the spines in this order of plants are not of axial, but of foliar origin, being in fact, strongly developed bud-scales. Tubers of Orchideae-IF — M. Leclerc du Sablon states that in the Orchidese ( Ophrys aranifera ), during the period when the tubers are being formed, they contain an increasing quantity of starch ; the sugars, which are at first abundant, disappearing almost entirely. When the tubers give up their reserve food-material, the amyloses are first transformed into saccharose, then into glucose. Like many other perennial plants, the period of greatest vital activity is the winter months, from September to May ; the summer months from May to September being a period of comparative repose. * Acta Horti Bergiani,iii. (1897) 19 pp. and 1 pi. See Bot. Centralbl., Ixx. (1897) p. 292. t Proc. Acad. Nat. Sci. Philadelphia, 1897, pp. 181-3. X Tom. cit., pp. 183-5 (1 fig.). § Flora, lxxxiii. (1897) pp. 441-53 (7 figs.). || Proc. Acad. Nat. Sci. Philadelphia, 1897, pp. 174-5 (1 fig.). 1 Comptes Rendus, exxv. (1897) pp. 1 34-6. ZOOLOGY AND BOTANY, MICRO 3COPY, ETC. 407 Tubers of Aconitum.* — Dr. C. Hartwich describes several different kinds of abnormality in the tubers of species of Aconitum , natives of Switzerland, and derives from them conclusions as to the genetic relation- ship of the species. They comprise irregularities as to the disposition of the cambium and of the elements of the vascular bundles, and in the occurrence of a layer of cells in the cortex distinguished from the rest of this tissue by a difference in their refractive power. Replacement of the Primary Root by a Secondary Root.| — Accor- ding to M. Boirivaut, it very frequently happens when the primary root of a Dicotyledon is destroyed, that a secondary root takes its place, and this secondary root then assumes very much the structure of the primary root. This is especially manifested in an increase in the number of vascular bundles. Spinous Roots 4 — Dr. D. H. Scott records two instances of this un- usual structure, — in Dioscorea prehensilis, and in Morseci sp. belong- ing to the Irideae. In the former case these spinous roots are produced entirely underground ; in the latter they spring from the swollen base of the stem. In both cases they resemble true roots in their anatomical structure. Structure of Bromeliaceae.§ — The late Dr. F. Muller records his observations on several species of this order, natives of Brazil. The honey-glands of Vriesia are described, situated on the septa of the ovary. In many species of Tillandsieae the author finds bracteoles ( Vorblatter'), the existence of which has not been detected by previous observers. Morphology of Thelygonum Cynocrambe.jj — Of this remarkable plant of the Mediterranean flora, of uncertain affinities, placed by Lindley among the Chenopodiaceae, Dr. G. Balicka-Iwanowska has made a detailed examination, of which the following are the more important results. The stem is monopodial. The male flowers have no rudiments of bracts or supporting leaves, while the female flowers have both. The ovules, which are at first horizontal and anatropous, assume later a horseshoe shape. A large amount of mucilage is present in the colleters and in a circular swelling of the leaf-stalk. £. Physiology. Cl) Reproduction and Embryology. Moebius on Reproduction .t — Prof. M. Moebius has brought together in one volume all his previous observations on the various modes of reproduction in the vegetable kingdom, and has added some new obser- vations and theories. Instead of the primary classification of modes of reproduction into sexual and non-sexual, he proposes one into reproduction by buds and by germs ; the distinction lying in the rejuvenescence of the cell or cells in the case [of germs, while no such rejuvenescence takes place in the * Bot. Centralbl., lxx. (1897) pp. 114-20, 14G-52, 178-84 (2 pis.). f Coraptes Rendus, exxv. (1897) pp. 136-8. + Ann. of Bot., xi. (1897) pp. 327-32 (2 pis.). § Flora, Ixxxiii. (1897) pp. 454-86 (2 pis.). || Tom. cit., pp. 357-66 (10 figs.). % ‘ Beilr. z. Lehre v. d. Fortpflanzung d. Gewachse,’ Jena, 1897, vi. and 212 pp. and 36 figs. 408 SUMMARY OF CURRENT RESEARCHES RELATING TO case of buds, but only growth by ordinary cell-division. An individual is a body which cannot be divided in such a way that the division gives rise immediately to two or more entirely new bodies. He combats the prevalent idea that continuous vegetative multiplication necessarily results in degeneration. The banana, date-palm, &c., are never repro- duced sexually in cultivation. Cultivated plants which are reproduced by seeds (cereal crops, &c.) are as liable to injury from parasitic fungi as those which are propagated from buds or cuttings. In most cases vegetative propagation has been the result of un- favourable conditions for the production of sexual organs or for the ripening of the seed. The advantages presented by sexual reproduction are : (1) the type of the species is more readily preserved by unispecific crossing; (2) by bispecific crossing the production of new species is (not made possible, but) rendered more easy; (3) it is a means for the development of more highly organised forms. There is no relation- ship between the complexity of the vegetative structure and that of the sexual organs. Embryogeny of Sagittaria.* — Mr. J. H. Schaflher finds the deve- lopment of the pollen-grain, embryo-sac, and embryo of Sagittaria variabilis to agree in general terms with that in Alisma Plantago. The generative nucleus divides into the twro male nuclei long before the dehiscence of the anther, making a trinucleated pollen-grain. The two polar nuclei usually fuse completely before impregnation, the centro- spheres and nucleoles appearing also to fuse. The three antipodal cells are usually surrounded by cell- walls before impregnation. The embryo- sac becomes divided, after impregnation, into two parts, the growth and curving of the embryo-sac taking place practically entirely above the division-wall. The pollen-tube expands, as it enters the embryo-sac, and passes down on one side past one of the synergids, which disappears at this time. The two male nuclei both enter the embryo-sac with the pollen-tube, but only one of them leaves the tube and takes part in fer- tilising the oosphere. Two very distinct centrospheres precede the male nucleus as it passes through the end of the tube. The apex of the tube appears to be ruptured by the passage of the nucleus. As the male nucleus approaches the oosphere, the latter developes a large bulge on the side facing the pollen-tube, two centrospheres sometimes appearing on the bulge. Centrospheres appear in resting nuclei and in division- stages; and, just before the contact and during the fusion of the male and female nuclei, two pairs of centrospheres appear, which seem to fuse simultaneously with the male and female nuclei. Cleistogamy in Umbel lifer se.f — Mr. T. Meehan describes a peculiar kind of cleistogamy in Cryptotsenia canadensis . It has two kinds of flower, male and hermaphrodite. In the latter the stamens, with short filaments and polliniferous anthers, are all enveloped in an extremely fugacious corolla, beneath which pollination is effected before the flowers open. Double Pollination.J — From experiments made on the hybridisation of several species of Marica , natives of Brazil, the late Dr. F. Miiller contests the assertion of Gaertner that the mixed pollination of a stigma * Bot. Gazette, xxiii. (1897) pp. 252-72 (7 pis.). Cf. this Journal, 1896, p. 436. t Proc. Acad. Nat. Sci. Philadelphia, 1897, pp. 177-8. t Flora, lxxxiii. (1897) pp. 474-86. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 409 by different kinds of pollen produces no mixed types, but that each kind of pollen, on tbe contrary, exercises its own effects entirely independently of tbe others. He confirms, on the other hand, Kolreuter’s statement that, when different kinds of pollen act at the same time, on the same stigma, forms result which present intermediate characteristics ; half- bastards or “ tinctures ” when a small quantity of a plant’s own pollen and a large quantity of a foreign pollen are used. Pollination of Cyclamen.* — Herr F. Hildebrand describes a peculiar contrivance for aiding cross-pollination in the spring-flowering species of Cyclamen ( C . persicum , coum, ibericum, &c. When the pollen first escapes from the terminal orifice of the anther, the pollen-grains adhere together in lumps by an oily secretion, which prevents their falling on to the stigma in the same flower. The first portion of the pollen leaves the anther in this condition, and is abundantly carried away by the numerous visiting insects. The oily secretion, however, rapidly dries up ; and when the later portion of the pollen falls from the anther — at which time insects are no longer visiting the flowers — the grains are dry, and are readily carried by the wind to other flowers. The autumn-flowering species of Cyclamen ( C . grsecum , neapolitanum, africanum) appear not to be visited by insects. In most species of Cyclamen (e.g. C. persicum) the stigma ends abruptly in a flat surface, which is not papillose or hairy, but has a deep depression in which the pollen collects. In C. ibericum and coum , on the other hand, the stigma is provided with a tuft of papillae, from which the stigmatic fluid secretes that detains the pollen-grains. Cross-Pollination and Self-Pollination.— Mr. C. Robertson’s f latest contribution to this subject treats of the adaptations for pollination and the insect-visitors of a number of species belonging to different natural orders growing in Illinois. JDr. P. Knuth X has investigated the pollination phenomena of the flora of Heligoland. Out of 174 species of flowering plants, 50, or about 30 per cent., are anemophilous ; Zostera marina is hydrophilous ; Lemna trisulca does not flower. The pollinating insects are chiefly flies ; there are a few Lepidoptera, but no honey-bees or humble-bees. The same writer § describes the mode of pollination in Matthiola incana and Lunaria biennis. In both species the two shorter stamens seem designed for cross-pollination by insects, the four longer ones for self-pollination when cross-pollination fails. Both species are visited by butterflies : — the former by Vanessa TJriicse ; the latter both by the small tortoise-shell and by Pieris Brassicse , also by a bee, Anthophora pilipes. In this case also, a bee, Andrena Gwynana , and a hover-fly, Syritta pipiens, are efficient in self-pollination. In both species the male and female organs mature synchronously. (2) Nutrition and Growth (including- Germination, and Movements of Fluids). Laws of Growth. || — From observations made on a variety of plants, Sig. L. Montemartini concludes that the activity of the growing point * Ber. Deutscli. Bot. Gesell., xv. (1897) pp. 292-8(4 figs.). t Trans. Acad. Sci. St. Louis, vii. (1893) pp. 151-79. i X Bot. Jaarb. Gent, 1896, 47 pp. and 1 pi. See Bot. Centralbl.,lxx. (1897) p. 274. § Bot. Centralbl., Ixx. (1897) pp. 337-40 (6 figs.). U Atti 1st. Bet. r. Univ. Pavia, v. (1896). See Bot. Centralbl., Ixx. (1897) p. 276. 410 SUMMARY OF CURRENT RESEARCHES RELATING TO exhibits a great period, dependent on internal causes. There is a con- nection between the apical and the secondary growth, the two curves coinciding ; the maximum of apical activity corresponds to the greater length of the zone of growth ; both processes are influenced by external agencies. Similar laws apply to the growing point of the root. In the case of annual woody plants, growth in thickness (growth of the secondary meristem) exhibits a periodicity dependent on internal causes, corresponding to the periodicity of the primary meristem, but indepen- dent of it. The formation of an annual ring is the immediate con- sequence of spontaneous and periodic changes in the activity of the cambium ; the periodicity in the activity of the cambium is indepen- dent of that of the primary meristem, although both are influenced by external conditions. Rhythmic Growth in Plants.* — Mr. T. Meehan adduces a number of examples of the effect of “rhythmic growth ” in producing apparent irregularities in the growth of plants. To this he attributes the occasional irregularity and the dimorphism in the flowers of Phlox and other genera of Polemoniaceae. The so-called “ polarity ” of the leaves of Silphium laciniatum and other “compass-plants” is due to the same law. In many cases (e.g. Gleditschia) , glands are the result of the arrested de- velopment of a branch — another illustration of the action of this law. The author points out also the small amount of evidence of the occur- rence of hybrids in nature, even when the conditions appear to be specially favourable to the crossing of different species. The forms often regarded as hybrids he believes to be varieties dependent on the operation of the law of rhythmic growth. Growth of Allium ursinum.j — Herr A. Rimpach notes a periodicity in the development of this plant. In the autumn, slender roots which are not contractile spring from the primary axis ; also slender lateral roots from those formed in the previous spring. At the same time the bulb, consisting of a bud and a single leaf, begins to grow ; the foliage- leaves developing in the course of the winter. In the spring the leaves appear above ground, and quickly unfold, the old bulb-leaf disappearing. Contractile roots are now formed, which drag the plant downwards into the soil. The foliage-leaves, the innermost of which is transformed into a receptacle for food-material, continue their function till August, when they wither. Growth of Colchicum autumnale.J — In this plant Herr A. Rimpach finds that the gradual sinking of the corm in the soil is not effected by the agency of contractile roots, or not to any appreciable extent. This de- pression takes place year after year, until the corm has sunk to a depth of about 15 cm., which may require about 20 years. After that it remains nearly stationary. Growth begins in the late summer or autumn, by the production of numerous slender roots at the time when the flowers expand. The assimilating period of the leaves lasts from April till July. Fleshy roots make their appearance in April or May, which have a strong resemblance to the contractile roots of other underground stems, but . * Proc. Acad. Nat. Sci. Philadelphia, 1897, pp. 178-81, 191-3, 194-6, 196-9. t Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 248-52 (1 pi.). j Tom. cit., pp. 298-302 (1 pi.). _ ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 411 which appear to have no contractile property. The growing point and the whole corm are constantly forced downwards by the growth of the new buds which are formed on its upper surface. Germination of Cryptocoryne.* — Prof. K. Goebel describes the structure of Cryptocoryne spiralis and ciliata , marsh plants, species of Aroideae, in which the embryo germinates while still attached to the plant. The small spadix is completely hidden within the spathe; an outgrowth from the spathe above the spadix prevents the access of larger animals, while small insects enter freely, and effect the carriage of the pollen to the stigma. The ovules are characterised by the very strong development of the outer integument. When the embryo begins to ger- minate, the cotyledon serves as an absorptive organ, and after the endo- sperm has been consumed, the embryo derives the greater part of its nutriment from the outer integument of the ovule. Phenomena of Symbiosis.f — Mr. A. Schneider classifies the phe- nomena of symbiosis under the following heads : — I. Incipient Symbiosis (Indifferent Symbiosis). 1. Accidental Symbiosis. 2. Contingent Symbiosis. II. Antagonistic Symbiosis. 1. Mutual Antagonistic Symbiosis (Mutual Parasitism). 2. Antagonistic Symbiosis (Parasitism). a. Obligative Antagonistic Symbiosis. b. Facultative Antagonistic Symbiosis. 3. Saprophytism. a. Facultative Saprophytism. b. Obligative Saprophytism. III. Mutualistic Symbiosis. 1. Nutricism (Semi-mutualistic Symbiosis). 2. Mutualism. 3. Individualism. a. Semi-individualism. b. Complete Individualism. IV. Compound Symbiosis. Accidental symbiosis represents the least specialised form, and is of wider occurrence than all the others combined. Contingent symbiosis ( Raumparasitismus ) involves a preference displayed by one organism for living in contact with another. Nutricism is illustrated in myco- rhiza, such as that of the roots of Cupuliferte ; mutualism in the root- tubercles of the Leguminosse. The two forms of individualism occur in the lower and the higher forms of lichens. Compound symbiosis is found especially in the animal kingdom. Effect of Mineral Salts on Development.! — M. C. Dassonville has experimented on the effect of solutions of mineral salts (chiefly Knop’s solution) on the growth of different grasses (wheat, rye, oat, maize, &c.) as compared with that of pure water. He finds the general result to * Flora, lxxxiii. (1897) pp. 426-35 (12 figs.), f Minnesota Bot. Studies, 1897, pp. 923-48. t Comptes Rendus, cxxiv. (1897) pp. 1467-70. 412 SUMMARY OF CURRENT RESEARCHES RELATING TO be that, with distilled water, the tissues are less fully developed, while, on the other hand, they are more strongly lignified. Thus, in a saline solution, both the roots and the stem become larger ; the size, both of the vessels and of the air-cavities, is increased ; while the walls of the former are less strongly lignified. Effect of Electricity on Vegetation.* * * § — Mr. Asa S. Kinney records the results of a series of observations on the effect on germination of a continuous electric current. With a small alternating current of moderate frequency and high voltage, there was in all cases an increase in the rapidity of germination and elongation of the radicle and hypo- cotyl. There was a distinct optimum above and below which the treat- ment was less effective, though never injurious. (3) Irritability. Movements of Swarm-Spores, Antherozoids, and Plasmodes.j* — Dr. R. Kolkwitz gives a resume of the literature published during the years 1885-1896 under the following heads: — Mechanics of the move- ments of Diatoms, Swarm-spores, Bacteria, Antherozoids, Oscillatoriacese, Desmidiacese, Gregarinese, Plasmodes, Amoebae, Flos-aquae, Phycochro- maceae and Radiolarieae ; the influence on the movements of Light, of Chemical substances, of Heat, of Moisture, of Gravitation, and of Electricity. Gamotropic and Carpotropic Movements.:*: — Prof. A. Hansgirg gives a further very extended list of plants in which the parts of the flower, or the flower-stalk or fruit-stalk, exhibit movements of curvature for the protection of the reproductive organs, or to assist in pollination, or to place the fruit in a more favourable position for the ripening of the seeds. The gamotropic movements are arranged under the follow- ing classes : — (1) plants [in which the flowers or inflorescences open or close periodically ; (2) plants with ephemeral or pseudo-ephemeral flowers which open only by day or only by night ; (3) plants with non- gamotropic flowers which open only once, and remain open until they wither; (4) plants with pseudo-cleistogamic and hemi-pseudo-cleisto- gamic flowers. Of carpotropic movements the following 8 types are recognised : — (1) the Arena- type; (2) the Oxalis- type; (3) the Primula-type; (4) the Coronilla-type ; (5) the Veronica- type; (6) the Aloe- type; (7) the Frag aria- type ; (8) the Aquilegia-type. Special attention is paid to the carpotropic curvatures of sepals and bracts. Further observations are also described on nyctitropic and para- heliotropic movements, on the irritable movements of stamens and stigmas, and on irritability in general. Ombrophoby of Elowers.§ — By this term Prof. A. Hansgirg de- signates the phenomena of curvature by which many flowers protect * Bull. Hatch Exp. Station (Amherst, Mass.), No. 43, 32 pp. See Bot. Gazette, xxiii. (1897) p. 302. t Bot. Centralbl., lxx. (1897) pp. 184-92. X S.B. K. Bohm. Gesell. Wiss., 1896, 111 pp. and 1 pi. Cf. this Journal, ante, p. 144. § Tom. cit., 67 pp. and 2 pis. Cf. this Journal, 1890, p. 484. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 413 themselves against injury from long-continued rain or other exposure to moisture. Such plants belong mostly to the xerophilous vegetation of temperate climates. They may be arranged under four types, viz. : — (1) Plants whose flowers close their perianth in rainy weather in such a way that drops of rain cannot enter (or only with difficulty) the flowers which are open in fine weather ; the position of the flowers or inflorescence not being altered. (2) Plants in which, after the flower opens, the flower-stalk curves in rainy weather, in such a way that the opening of the flower, previously directed upwards, changes its position so as to protect the pollen or nectar against the rain. (3) Plants in which a similar movement takes place in the stalk of the inflorescence. (4) Plants in which the movements characteristic of the second and third type are accompanied by a closing of the perianth. In addition, the author gives a list of flowers in which the protection of the pollen against rain does not depend upon a photo-dynamic principle. Curvature of Roots.* — Prof. D. T. Macdougal has carried out a series of observations on the localisation of the curvature of roots, and the causes which give rise to it. Curvatures in general he regards as due to changes in the cell-wall rather than in the osmotic activity of the cell-contents. But the curvatures of stems are not identical with those of most tendrils or of many roots. The curvature of roots is due tto the excessive active elongation of the internal layers of the cortex of the side becoming convex, made feasible by the increased stretching capacity of the longitudinal membranes. In consequence of the stretching, the membranes of the convex side become thinner ; and, as a later effect, the membranes of the concave side become thicker. The organs of the irritable mechanism of roots exhibit a physiological rather than a morphological differentiation. The part of the root affected may be divided into a sensory zone and a motor zone. The movement of a root is caused by changes in the region in which the energy of the periblem is turned from cell-division to cell-enlargement. The sensory zone consists of a cup-shaped mass of periblem extending 1-2 mm. axially, from which the bottom, representing the growing point, is wanting. The sensory zone extends approximately to the forward edge of the motor zone. The motor zone includes a length of 2-3 mm. The curvatures of roots apical and basal to the motor zone are me- chanical accompaniments of the action of the motor zone. Rheotropism and Thermotropism in a Plasmode.j — Mr. J. B. Clifford has studied these phenomena in the sclerote of a Myxomycete, probably Fuligo varians , which could be induced to assume the active plasmode condition by supplying it with abundant moisture. Up to a certain point the plasmode was found to be positively rheotropic, but a very slight increase in the strength of the current of water caused it to become negatively rheotropic ; any considerable increase in the strength of the current induced it to move entirely away from the water. As to thermotropism, the plasmode will live in an atmosphere ranging from — 2° to 52°-53° C. ; it remains positively thermotropic up to 33°-34° C., becoming negatively thermotropic above that point. * Bot. Gazette, xxiii. (1897) pp. 307-66 (1 pi. and 7 figs.). t Ann. of Bot., xi. (1897) pp. 179-86 (3 figs.). 414 SUMMARY OF CURRENT RESEARCHES RELATING TO (4) Chemical Changes (including Respiration and Fermentation). Action of Diastase on Reserve-Cellulose in Germination.* — Dr. J. Griiss describes this process in further detail, the species specially- studied being the date-palm. During germination the diastatic enzyme passes from the cell-cavity into the thickened cell-wall, especially in the neighbourhood of the scutellum. This is followed by a partial hydrolytic solution, by which the galactan is removed from the cell- wall. In this manner the hyaline marginal zone is formed. The mannan which remains in this zone undergoes alloolysis ; the mass which is permeated by the enzyme passes over into the various mannin stages, and finally into mannose. According to the reactions a leuco- mannin and a cyanomannin can be distinguished. Alcoholic Fermentation without Yeast-Cells.f — Herr E. Buchner finds that the aqueous extract loses its fermentative properties when kept for two days at 0°, or for one day at the ordinary temperature. This deterioration, which is accompanied by a loss in coagulable albumen, is attributed to the presence of peptonic enzymes. The extract retains its activity much longer in the presence of strong solutions of cane- sugar. When the extract is mixed with its own volume of a 50 per cent, solution of cane-sugar, fermentation continues for 7 days at moderate temperature, and for 14 days at 0°. That the activity is not due to the presence of plasma particles in the extract, is proved by the fact that the activity of the solution is not destroyed by antiseptics, such as chloroform, benzene, sodium arsenite, &c. The extract may also be evaporated to dryness at 30°-35° under reduced pressure ; and an aqueous solution of the residue is also capable of fermenting cane-sugar. The dried extract may be kept for at least 20 days without losing its active properties. Only on one occasion was it found possible to precipitate the active substance, zymase, by the aid of alcohol. Well warmed yeast was dried at 37°; one portion was mixed with water and heated to 100°; plate cultures proved that all the cells had been destroyed, and yet the solution was capable of fermenting a sterilised cane-sugar solution. The second portion was heated to 140°-145° for one hour ; it was found to be incapable of bringing about fermentation, owing to the de- struction of the zymase. Reduction of Nitrates.* — M. P. P. Deherain made a number of experiments in which solutions ofjfpotassium nitrate were inoculated with straw, fresh manure, horse-dung, and peat manure. Nitrate-reducing organisms were found in straw and fresh manure, but not in peat manure. Horse-dung contained sufficient to reduce nitrates at 30°, but there was very slight reduction at the ordinary temperature. The denitrifying organisms develop rapidly in solutions containing starch and potassium nitrate, but not at all in pure nitrate solutions. The organisms will live in starch alone ; but in absence of nitrate the starch is only very slowly destroyed. Solutions exhibiting the most rapid reduction contain starch (0*25), potassium nitrate (0*2), and potassium phosphate (0*01 * Bot. Central bl lxx. (1897) pp. 242-61 (2 pis.). Cf. this Journal, 1895, p. 200. t Ber. Deutsch. Chem. Gesell., xxx. (1897) pp. 1110-3. See Journ. Chem. Soc.,. lxxi. and lxxii. (1897) pp. 380-1. Cf. this Journal, ante , p. 222. X Ann. Agronom., xxifi. (1897) pp. 49-79. See Journ. Chem. Soc., lxxi. and lxxii. (1897) pp. 381-2. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 415 per cent.). Experiments with soil showed the presence of denitrifying organisms, and that by adding starch a considerable amount of the nitrates present in the soil could he destroyed, while the addition of straw had very little effect. The amount of nitrogen utilised by the reducing organisms is very slight, nearly the whole of the nitric nitrogen being liberated as gas, chiefly free nitrogen. Reduction takes place more readily in closed vessels than in the open air, and is retarded by passing air through solutions containing starch and potassium nitrate. There is no danger of loss of nitrogen by the application of the usual amounts of manure. Reduction of nitrates would only take place when the manure amounted to 400,000-800,000 kilos, per hectare. Hence it is quite unnecessary to treat stable manure with sulphuric acid before using it. Nitrates in Seedlings.* — Herr E. Schulze finds potassium nitrate in very small quantities in etiolated seedlings of gourd and lupin grown in soil which does not contain nitrates. This may be the result of the oxidation in the soil of nitrogenous substances excreted by the root, the resulting nitrates being then again absorbed ; or it may be the result of the air of the laboratory containing small quantities of nitrates resulting from the oxidation of atmospheric impurities. B. CRYPTOGAMIA. Cryptogamia Vascularia. Anatomy of Lycopodium.t — According to MM. E. David and L. Weber, the ultimate ramifications of the vascular bundle consist (in Lycopodium clavatum) of a xylem-bundle and two halves of a bast-bundle. The central cylinder is surrounded by a pericambium composed of three or four layers. The outer and inner layers of the cortical tissue have sclerotised cell-walls. The phloem completely surrounds the xylem in each bundle. The sporange consists of a cup, from the hypodermal layer of which are developed the spore-mother-cells. The outer wall is composed at first of a single layer, which subsequently splits into three ; the innermost of these three is the nutrient layer of the spores. Oophyte of Botrychium.f — Mr. E. C. Jeffrey has studied th& structure and development of the gametophyte (oophyte) generation of Botrychium virginiamm. The middle of the upper surface of the pro- thallium is occupied by a well-defined ridge, upon which the antherids are situated. The archegones are found on the declivities which slope away from the antheridial ridge. The cells of the tissue which composes the lower surface of the prothallium are filled with a yellow oil, and contain an endophytic fungus. The antherids project but little above the ridge ; the antherozoids are large, and resemble those of typical ferns ; only the neck of the archegone projects above the surface. The first division of the oospore (oosperm) is at right angles to the long * Zeitschr. f. Phys. Chemie, xxii. (1896) pp. 83-9. See Bot. Centralbl., lxxii. (1897) p. 361. f Bull. No. 15 Soc. syn. d. Pharmaciena de la Cote d’Or, 1897. See Bot. Cen- tralbl., lxx. (1897) p. 359. X Proc. Canadian Inst,, i. (1897) pp. 8-10. Ann. Bot., xi. (1897) pp. 481-6. 897 2 g 416 SUMMARY OF CURRENT RESEARCHES RELATING TO axis of the archegone ; the second is at right angles to the first. The prothallium is very long-lived, apparently living as much as six years. Formation of the Karyokinetic Spindle in Equisetum.* — Herr W. J. V. Osterhout gives the following as the main results of observa- tions in the first nuclear division in the spore-mother-cells of Equisetum limosum. At the time when the chromosomes separate, there is formed in the cytoplasm, close to the nuclear wall, a layer composed of fibres which at first run irregularly, but at length place themselves at right angles to the wall. Tufts of filaments are produced by the union of the polar ends. After the wall of the nucleus has disappeared, these filaments reach the nuclear cavity and combine with the fibres of the linin-framework. New groups are formed by fusion of the original groups, and then separate into two opposite divisions. Each division consists of several such groups, which finally fuse together and form a bipolar spindle. There appears to be a complete absence of centro- somes in this mode of formation of the spindle. Characeee. Division of the Nucleus in Chara.j — Herr B. Debski has investi- gated the mode of nuclear division in the vegetative cells and antheridial filaments of Chara fragilis. His conclusions differ materially from those of Johow, who was, he believes, led into error by mistaking the substance of the nucleoles for chromatin. The main results are as follows : — No distinct centrosomes could be detected in the process of division of the nucleus. Nucleole-like bodies are formed in the protoplasm, probably composed of nucleolar substance, and which show remarkable relationships to the spindle-fibres and the formation of the cell-plate. No reduction in the number of chromosomes takes place in the antherids. The process of karyokinesis exhibits much greater resemblance to that in the higher plants than to that in Algae. In Chara , as in the Archegoniata, the nuclear membrane is absorbed; while in most Algae karyokinesis takes place within the nuclear membrane, which is absorbed only at a later period. In Chara the formation of the cell-plate takes place centri- fugally. Shoot-Nodes of Characeae.J — Hr. K. Giesenhagen describes in detail the structure and mode of formation of the nodes in the aerial stems of the Characeae, especiallyfin Nitella gracilis and N. sy near pa. While the earlier stages in their formation show a remarkable uniformity through- out the family, a variety of differences are exhibited in the later stages, according to the species. Muscineee. Levierella, a new Genus of Musci. — Dr. C. Muller § defines as follows a new genus of Fabroniaceae from the Himalayas: — Cespites latos depressos entodontoideos sistens; caulis vage ramosus tenuis, ramis brevibus secundifoliis robustioribus, anguste subcomplanatis, et junioribus multo tenerioribus sparsifoliosis, valde divisus; folia e basi * Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 159-68 (2 pis.). (For method see p. 445.) f Tom. cit., pp. 227-48. Cf. this Journal, 1882, p. 79. (For method see p. 445.) % Flora, lxxxiii. (1897) pp. 160-202 (1 pi. and 17 figs.). Cf. this Journal, ante, p. 147. § Bull. Soc. Bot. Ital., 1897, pp. 73-4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 417 brevi subspathulata, cellulis alaribus quadratis subpellucidis ornata, in laminam ovato-acuminatam tenuiter serrulatam carinatam attenuata, nervo angustissimo evanido exarata, e cellulis fabroniaceis reticulata ; tlieca parva longius pedunculata entodontoideo-cylindrica rostrata oper- culata ; calyptra minuta dimidiata ; annulus latus persistens grande- cellulosus; peristomium duplex ; dentes externi 16, angustissimi lineares articulati pallide flavocornei, in dentes 4 coaliti latere parum cristati, intorni membranam adglutinatam obsolete dentatam sistentes; inflo- rescentia monoica. It is named Levierella. Gemmae of Aulacomnium.* — Herr C. Muller has studied in detail the formation of the gemmae or bulbils in Aulacomnium androgynum. It in all cases depends on the production of a two-edged (wedge-shaped) apical cell at the end of a leafless pseudopode or gemmophore, but the number of segments which are produced from this cell varies. Usually this apical cell divides into a large number of segments by walls alternately inclined in different directions. But not unfrequently the terminal cell first of all divides transversely into two at about half its length, and the apical cell then results from the further segmentation of the upper of these two cells. The basal cell also always undergoes further division. Algae. Encrusting and Perforating Algae.* — Prof. R. Chodat enumerates the Algae (and Protophyta) which form calcareous deposits on objects immersed in water. The Cyanophyceae coming under this head belong chiefly to the genera Calothrix and ScMzothrix ; species of the latter genus may penetrate calcareous rocks to a depth of 1-2 *5 mm. To them is commonly due the caries of pebbles. They also frequently attack bivalve shells. Species of Hyella living in consortism with a Gongrosira, a Gomontia, or a fungus known as Ostracoblabe , attack the shells of marine molluscs. Perforating properties to a very high degree are possessed by an alga apparently belonging to the genus Gongrosira , which invades the shells of Anodon in the Lake of Geneva. Iodine in Algae. :f — According to Herr Eschle, the iodine in Algae ( Fucus vesiculosus , Laminaria digitata ) is almost entirely in the form of an organic compound. Melobesiaceae.§ — Herr M. Foslie criticises, on several points, Hey- drich’s monograph of the Melobesiaceae. He maintains that there are no good generic characters by which LitJiophyllum can be separated from Lithothamnion. Sporolithon ptychoides must also be referred to the same genus. The alleged “ layers of tetrasporanges ” overgrown by new thallus- layers, are, according to the author, abnormal structures caused by the attacks of a Rhizopod, which either preys upon existing conceptacles, or bores for itself chambers having a close resemblance to con- ceptacles. Several also of Heydrich’s species are sunk by Foslie in previously described species. * Ber. Deutsch. Bot. Gosell., xv. (1897) pp. 279-91 (1 pi.). t Arch. Sci. Phys. et Nat., iii. (1897) pp. 512-4. + Zeitschr. Phys. Chem., xxiii. (1897) pp. 30-7. See Journ. Chem. Soc , 1897, Abstr., p. 339. § Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 252-60. Cf. this Journal, ante, p. 225. 2 G 2 418 SUMMARY OF CURRENT RESEARCHES RELATING TO Conjugation of Swarm-spores. — Herr F. Oltmanns* contests the accuracy of the well-known observations of Berthold on the conjugation of the swarm-spores (gametes) from the plurilocular sporanges of Edo - carpus siliculosus. From observations, made chiefly on E. criniger , he is able to state that, especially in cultivation, it is exceedingly common for the swarm-spores of this and of other algae to be attacked and devoured by Flagellata, and he believes this phenomenon to have been mistaken by Berthold for a conjugation of swarm-spores. Especially he calls attention to the rarity of observations of the germination of the assumed zygotes by Berthold or others. In reply, Dr. G-. Berthold f entirely denies the accuracy of Oltmanns’ interpretation of the observed phenomena, and gives further details, not hitherto published, of his own observations. He states that the swarm- spores exercise an influence on one another even before the female comes to rest. Fungi. Action of Alcohol on the Germination of the Spores of Fungi.J — According to M. P. Lesage, alcoholic solutions up to a concentration of 6-8 per cent, do not prevent the germination of the spores of Fungi ( Penicillium glaucum , Sterigmatocystis nigra). Above this limit alcoholic solutions impede germination, and finally kill the spores. A rise of temperature increases the toxic action. Mucorini.§ — M. M. Leger has studied the structure of the cell and the phenomena of conjugation in a large number of genera of Mucorini, and finds in all a great uniformity. In the hyphse the nuclei are very numerous, varying in diameter from 0*5 to 5 p ; they have a central deeply staining nucleole, sur- rounded by a peripheral layer which does not stain (with haematoxylin), the whole enclosed in a nuclear sac. The vegetative nuclei always divide directly ; mitotic divisions occurring only in the spores at the period of germination. The young zygosperm contains a very large number of nuclei de- rived from each gamete, which gradually disappear. As soon as the last have disappeared, two groups of bodies make their appearance, one at each end of the zygosperm, which the author terms “ embryogenic bodies ” ; they are naked masses of protoplasm apparently derived from the nuclei ; later, they fuse together in each group. These bodies, the “embryogenic spheres,” surround themselves with a double wall, and constitute the “ embryonic spheres ” of the mature zygosperm. When the zygosperm is about to germinate, these spheres lose their walls and unite to form a single central mass with numerous nuclei. In the for- mation of the azygospores, exactly the same process takes place, except that there is only one group of embryogenic bodies, and one embryonic sphere. The author regards the union of the embryogenic bodies as a true sexual process ; the azygospores are therefore as truly sexual bodies * Flora, lxxxiii. (1897) pp. 398-414 (1 pi. and 4 figs.). t Tom. cit., pp. 415-25. t Ann. Sci, Nat. (Bot.), iii. (1896) pp. 151-9. § ‘ Rech. s. 1. structure d. Mucorinees,’ Poitiers, 1896, 151 pp. and 21 pis. See Bot, Gazette, xxiii. (1897) p. 389. Cf. this Journal, 1895, p. 461. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 419 as the zygosperms. The phenomenon of conjugation is thus held to be a matter of secondary importance, "and not sexually significant in the group. Two new species of Mucor are described, M. rigidus, and M. rubescens with bright red sporanges. MucorSagglomeratus sp. n.* * * § — Herr. W. Schostakowitsch finds a new species of Mucor in putrid milk in Siberia. On bread it forms very dense greyish tufts, in which the much-branched sporangiophores are so densely crowded as to be indistinguishable by the naked eye. Each sporangiophore ends in a sporange, and the latter are also collected in nearly sessile clusters on lateral branches. Entomogenous Fungi.f — Mr. J. G. 0. Tepper enumerates the ento- mogenous fungi natives of Australia, all belonging to the genus Cordiceps. Thirteen species have been described, of which G. Gunnii is the most widely diffused. The species of larva which they attack are at present entirely unknown. Geoglossese.J — Mr. G. Massee gives a monograph of this family of the Discomycetes, consisting of the eight genera Geoglossum, Spatliularia, Vibrissea, Mitrula , Leotia , Spragueola , Hemiglossum , and Neolecta. The family is thus defined: — Ascophore stipitate, erect, aseigerous portion terminal, clavate, spathulate, or pileate ; asci elongated, narrowly clavate, eight-spored, dehiscing by an apical pore ; spores coloured or hyaline, septate or continuous; paraphyses present. Of Massee’s own genus Spragueola , the following diagnosis is given : — Ascophore sessile, sub- globose, irregularly nodulose, glabrous, solid, hymenium covering the whole surface, attached to the substratum by radiating mycelium ; asci narrowly cylindric-clavate, apex slightly truncate or obtuse, pore blue with iodine ; spores eight, obliquely 1-seriate, continuous, hyaline, smooth, elliptical ; paraphyses slender, septate. The author considers the family as most nearly allied to the Bulgarieae ; but there is an affinity with the Pezizese through Helotiumt and with the Helvelleae through Verpa. Development of the Tuberaceae. § — Herr. F. Bucholtz traces in detail the development of Tuber excavatum , belonging to the subgenus Aschion. He finds that it has a gymnocarpous origin, the hymenium becoming enclosed only in the course of its development. This establishes the close relationship of the subgenus to the genera Stephensia , Pachy- phloeus, and Genea , and renders highly probable the affinity of the Eutuberineae to the gymnocarpous Helvellaceae. Two isolated hyphal systems are present in the receptacle of Tuber excavatum , one of them ascogenous, the other resinigerous, indicating the great internal differ- entiation of the Tuberaceae. Similar resin-hyphae were found also in Hymenogaster decorus , confirming the view already put forward || of the parallelism of the two families Tuberaceae and Gasteromycetes. * Ber. Deutscli. Bot. Gesell., xv. (1897) pp. 226-8 (1 pi.), f Bot. Centralbl., lxx. (1897) pp. 305-7. x Ann. of Bot., xi. (1897) pp. 225-306 (2 pis.). § Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 211-26 (1 pi.). J| Cf. this Journal, ante, p. 153. 420 SUMMARY OF CURRENT RESEARCHES RELATING TO Sclerotinia.* * * § — Herr R. Aderhold describes in detail the structure, development, and mode of propagation of the “ Vermehrungspilz,” so destructive especially of gardeners’ cuttings. He regards it as a Peziza belonging to the form Sclerotinia , and nearly allied to S. sclerotioram. Sooty Mould of Citrus. — Mr. D. McAlpine f has determined the cause of the disease of various species of Citrus in Australia known as sooty mould to be a hitherto undescribed fungus which he names Capnodium citricolum. It is a polymorphic species, having Torula, Conio- thecium, and Heterobotrys-stages. There are two different kinds of hyphee — thin-walled, colourless or slightly coloured ; and thick -walled, distinctly coloured. The colourless hyphse produce conids, gemmte, aud glomerules ; the coloured hyphae produce conids and gemmae, also sper- mogones, pycnids, and peritheces. The fungus is saprophytic, living on the sweet excretion from scale-insects, and its spread has been materially promoted by the destruction of honey-eating birds. Mr. H. J. Webber,| on the other hand, attributes the “ sooty mould ” so destructive to the orange crop in Florida, to two species of Pyre- nomycetes, Meliola Penzigi and M. Camellise . These fungi are also saprophytes, deriving their nourishment entirely from the honeydew secreted by certain insect pests, which the fungus invariably follows. The most destructive of these insect pests is the mealy-wing, or white fly, Aleyrodes Citri ; and the author describes another fungus, Aschersonia Aleyrodis, which is parasitic on the larva and pupa of this insect. The principal reproductive bodies of the Meliola are conids, pycnids, stylo- spores, and peritheces. Parasitic Fungi. — MM. E. Prillieux and Delacroix § find a disease of mulberry trees in European Turkey to be due to the attacks of Scle- rotinia Libertiana, which forms sclerotes in the branches. A parasitic fungus which attacks the stems of many cultivated orchids, is determined by M. M. Mangin || to be Gloeosporium macropus. Under the name Acremoniella verrucosa sp. n., Sig. F. Tognini If describes a parasitic fungus destructive of the haulms of wheat and oat. Miss M. E. Olson ** has found a parasitic fungus on the leaves of Selaginella rupestris, belonging to the family Acrospermaceae, which oc- cupies an intermediate position between the Pyrenomycetes and the Discomycetes. It is named Acrospermum urceolatum sp. n. Mr. H. T. Soppitt || confirms his previous statement that Puccinia Diagrapliidis developes its aecidioform only on Convallaria majalis. * Minks’ s Microgonids.|| — Dr. A. Minks makes a vigorous reply to Darbishire’s criticisms on his theory of microgonids. He charges his critic with misrepresentation, with misinterpretation of observed phe- * Gartenflora, xlvi. (1897) pp. 114-26 (1 pi.). See Bot. Centralbl., lxx. (1897) p. 166. f Proc. Linn. Soc. N.S. Wales, xxi. (1896) pp. 469-99 (12 pis.). J Bull. No. 13 U.S. Department of Agriculture (Div. Veg. Phys. et Patk.^ 1897, 34 pp. and 5 pis. § Comptes Rendus, xxiv. (1897) pp. 1168-70. U Tom. cit., pp. 1038-40. *[ Rend. r. 1st. Lomb. sci. e lett., xxix. (1896) 4 pp. See Bot. Centralbl., lxx, (1897) p. 168. ** Bot. Gazette, xxiii. (1897) pp. 367-71 (1 pi.). tt Zeitschr. f. Pflanzenkr., vii. (1897) pp. 8-10. See Bot. Centralbl., lxx. (1897) p. 200. Hedwigia, xxxvi. (1897) pp. 177-89. Cf. this Journal, 1895, p. 665. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 421 nornena, and with the drawing of erroneous conclusions from insufficient experience. Origin of Saccharomyces.* — Under the title What do we know about the origin of Saccharomyces ? MM. A. Klocker and H. Schionning again discuss the hotly debated question of whether there is a genetic connection between the Saccharomycetes and the Hyphomycetes, or whether typical Saccharomycetes are to be regarded as independent fungi. They made numerous experiments with Aspergillus Oryzse, A. glaums, A. repens, with Dematium, Gladosporium , with four species of Penicillium, &c., but in no case obtained Saccharomyces-cel\& . Similar results1 were obtained from observation made on mould fungi growing under natural conditions. The main conclusion arrived at is that the Saccharomycetes are not a developmental phase of some other fungus, but that, like Exoasceae, they are independent organisms. Pathogenic Blastomycete found in Carcinoma.^ — Dr. D. B. Roncali publishes the results of a histological and bacteriological examination of an adenocarcinoma of the colon, with secondary deposits in the peri- toneum. In the juice of the deposits were observed round and oval highly refracting bodies, branched hyphae, and hyaline cells with double contour. Stained preparations of the juice gave evidence of Blasto- mycetes, and microscopical examination of a piece of tissue incubated for 56 hours showed that the Blastomycetes had increased in number. By treating masses of the highly refracting bodies with saturated solu- tions of caustic soda or potash, no effect was produced ; while in 4 per cent, hydrochloric or nitric acid they were dissolved without effervescence, and with 40 per cent, sulphuric acid needle-like crystals resembling those of gypsum were deposited. Histological examination of the cancerous tissue revealed the para- sites in astonishing numbers. By incubating some of the juice in a dilute acid solution of sugar, a Blastomycete was isolated in 47 out of 60 tubes. The parasite, which caused death in guinea-pigs in from 15-30 days, was recognised by the author as Blastomyces vitrosimile degenerans. Herring-Brine Yeast.J — The brine used for pickling herrings is, says Dr. C. Wehmer, unusually rich in living germs, the predomi- nating organism in that used at Emden being a Blastomycete termed by the author salt-yeast. The organism was easily isolated and culti- vated in gelatin containing 10 per cent, of salt, a quantity sufficient to prevent the growth of all fungi except Penicillium glaucum. Morphologically the cells are spherical, oval, or elongated, invested in a delicate colourless membrane enclosing homogeneous or granular contents, wherein, according to age or other circumstances, may be ob- served a vacuole. The yeast was easily cultivated on solid or in liquid media without or with salt (3-15 per cent.). About eight millions of cells appear to be' contained in each cubic millimetre of brine. Esti- mated by means of nitrate of silver, the Emden brine was found to contain 23-24 per cent, of salt. To a great extent cultural experiments confirmed the expectation that salt would, at least up to a certain per- * Ann. de Micrographie, ix. (1897) pp. 233-50. Cf. this Journal, 1896, p. 339. t Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 517-23. X Op. cit., 2te Abt., 1897, pp. 209-22 (1 pi.). 422 SUMMARY OF CURRENT RESEARCHES RELATING TO centage, be favourable to tbe growth and multiplication of tbe yeast; for 10 and even 15 per cent, was found not to be deleterious. Besides this insensitiveness to the presence of salt, even in large quantity, this organism also possesses an unusual resistance to conditions extremely unfavourable to vegetation, such as exclusion of air, concentration of the medium, or the presence therein of alcohol or acetic acid. The exact source of the yeast is undetermined, though a marine origin is the most probable. Morphology of Blastomycetes.* — In his researches on the mor- phology of Blastomycetes Dr. O. Casagrandi discusses at some length the membrane and the granules. The membrane is declared to be not a simple structure, but composed of two or more layers, both in the old and young ferments. Chemically the membrane is closely allied to pectin, and its principal characteristics are that it does not give the cellulose reaction with iodine ; it is soluble in strong chromic and sul- phuric acids ; is insoluble in Schweizer’s reagent, even if previously treated with hydrochloric acid, alcohol, or 2 per cent, acetic acid ; and is only stained with difficulty by carminic or anilin dye solutions. The granules are represented as protoplasmic vesicles filled with a fatty substance which, according to the age of the cell, is liquid or solid. While these granules exhibit microchemical reactions proper to fatty substances, they also give some of the reactions indicative of proteid or nuclein. The latter are stated to be due to the investment, the former to the contents. With regard to the nucleus, the author expresses his certain belief in its existence. Myxomycetes. Pseudocommis Vitis.f —This Myxomycete, detected by M. Debray in the leaves of diseased potatoes, has now been observed by M. E. Roze in the hypodermal cells of the tubers, in the form both of plasmoaes and of cysts. It attacks both the nucleus and the starch-grains. The author finds its occurrence very common in garden and greenhouse plants. The black and brown spots that indicate the malady known by gardeners as “ burning ” are due to the attacks of this parasite. It is often over- looked, owing to its very rudimentary structure, consisting of plasmode- like mucus, which becomes encysted in certain conditions. As long as this plasmode is in a living condition, it is able to escape, under favour- able conditions, and infect other vegetable tissues. The author further records the presence of this parasite in the leaves of Elodea canadensis , in the marine flowering plants Zostera and Bujppia, and in Fucus serratus and vesiculosus. Protophyta. o. Schizophycese. Protophyta of the Norwegian Nordhavs Expedition, 1876-784 — Herr H. H. Gran’s contribution to this publication includes the Diato- * II Naturalista Siciliano, ii. (1897) pp. 1-24. t Comptes Rendus, exxiv. (1897) pp. 704-5, 1109-11, 1470-2; exxv. (1897), pp. 362-63, 410-11. Cf. this Journal, 1896, p. 215. X Christiania, 1897, 36 pp. and 4 pis. (Danish and English). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 423 macese, Silicoflagellata, and Cilioflagellata. After some general remarks, the species are described in detail. The Diatoms belong chiefly to the genera Ghsetoceros and Coscinodiscus. The modes of reproduction of Ghsetoceros are described in detail, and the species are arranged in two subgenera, Plneoceros, with thick, often spinous setae, hollow, and filled with protoplasm and chromatophores ; and Hyalochaete, with slender colourless setae. There are a number of new species. The Silicoflagel- latum found is Bistephanus speculum ; and the Cilioflagellata are Cera - Hum tripos and C . fusus. Structure of Cyanophycese and Schizomycetes.* — After a detailed account of the researches and views of other observers on the structure of these organisms, Herr A. Fischer expounds his own views, which are in strong opposition on several points to those of Biitschli. In the first place he contends that staining reactions are dependent on the physical rather than the chemical structure of the object ; that, in particular, there is no true nuclear pigment ; and that the staining pro- perties offer no certain indication of the place of the object stained in any special group of proteid-substances, or of the morphological value of a cell-element. The Cyanophycese possess a true parietal chromatophore, which is usually cylindrical ; in it lies the so-called central body. This cannot be regarded as the phylogenetic ancestor of the nucleus of higher plants ; it possesses no true chromatin ; its granulations are simply collections of reserve-substances. In the sulphur-bacterium Chromatium the pigment is not collected into a peripheral layer, but colours the cell-contents uniformly ; there is no differentiation into a cortical and central portion. Neither in Chro- matium nor in Beggiatoa is there any structure which can be regarded as a nucleus. The figment of a central nucleus is the result of plasmo- lysis. The bacterium-cell consists of a parietal layer of protoplasm, and an inner cell-sap-cavity which may be traversed by septa of proto- plasm. The author regards the Bacteria as more nearly allied to the Flagel- lata than to the Cyanophycese. New Genera of Cyanophycese. — Under the name Loefgrenia anomala g. et sp. n., M. M. Gomont j* describes what he regards as probably the type of a new family of Nostocacese. The following is the diagnosis of the genus : — Planta myxophycea, filamentosa ; trichomata evaginata, basi affixa, pilifera, in parte inferiori passim ramosa, ramificatione vera; heterocystse nullse ; homogonia et sporae usque adhuc ignota. Among a large number of new species from tropical Africa, Messrs. W. and G. S. West J find the following new genera : — Camptothrix. Plantm minutse, filamentosse et epiphytic® ; fila brevis- sima, haud ramosa, e serie singula cellularum irregularium formata, supra algas majores aquaticas repentia, irregulariter flexuosa et sub- moniliformia, vaginata ; vagina delicata, arcta et hyalina ; cellulse sub- * ‘Unters lib. d. Ban d. Cyanophyceen u. Bakterien,’ Jena, 1897, 136 pp. and 3 pis. See Bot. Centralbl., Ixxi. (1897) p. 62. Cf. this Journal, ante, p. 235. f Wittrock, Nordstedt, and Lagerkeim; Algse aqu® dulcis exsiccatce, fasc. 26-9, Stockholm, 1896. X Journ. of Bot., xxxv. (1897) pp. 261-72, 297-301 (l pi. and 2 figs.). 424 SUMMARY OF CURRENT RESEARCHES RELATING TO globosse, rotundo-quadratae v. subrectangulares, apicem versus filorum minores, prope apicem filorum vaginis indistinctis v. destitutis ; pro- toplasma pallide aerugineum et liomogeneum. The authors make this genus the type of a new family, Campto- triche2e : — Ordo novus Homogonearum Homocystearum. Fila brevia, vaginata, irregulariter flexuosa, extremitates versus attenuata, serie ir- regulari, singula cellularum intra vaginam unamquamque, cellulis baud uniformibus, vaginis delicatis et achrois. Polychlamydum g. n. Yaginariarum. Plantae aquaticae; fila subbrevia (4-6 mm.), flexuosissima et sine ramis ; vaginae amplissimae e serie tubarum concentricarum constitutae, tubis interioribus firmissimis et coloratis, iis exterioribus hyalinis et plus minusve diffluentibus, apice aperto et leviter expanso ; trichomata solitaria, nonnunquam 2 v. rarius 3 intra vaginam; apice trichomatis recto; cellulae brevissimae. Proterendothrix g.n. Lyngbyearum. Plantae minutae, primum endo- phyticae, turn epiphyticae, fila solitaria v. 2-3 associata, brevia et sim- plicia ; vaginae achroae, hyalinae et amplae, marginibus irregularibus ; trichomata solitaria intra vaginam unamquamque. B. Schizomycetes. Sulphur Bacteria of the Hot Springs of Yumoto.* — Prof. M. Miyoshi found in the hot springs of Yumoto, in Japan, the following colourless sulphur bacteria : — Thiothrix nivea , and a new variety thereof, Th. nivea var. verticillata , the cells of which are from 2*5-3 y long; also Thiothrix tenuis and Beggiatoa alba. The following red sulphur bacteria are enumerated : — Chromatium Weissii, Chr. minus, Chr. venosum , Chr. minutissimum, and Thioderma roseum sp. n. The cells of the latter are spheroidal, 2*5 y long and 1*5 y broad, are of a pale red colour, and contain minute sulphur granules. It forms a thick red-purple scum, and is found on vegetable matter at 27° C. It would appear that in quick-flowing streams the sulphur is deposited in amorphous granules or imperfect crystals, the tufts then being more white than yellow. When the current is slow the sulphur is deposited usually in longish rhombic octahedra, the tufts then being yellow. In the zoogloea-masses there are numberless sickle-shaped bacteria, asso- ciated with a greater or less number of other species ; these have been already alluded to. Much attention was paid to the chemotactic sensi- tiveness of Chr. Weissii , which was found to be attracted by dilute solutions of H2S, ammonium tartrate and phosphate, and potassium nitrate, while stronger solutions of these substances repelled these organisms. Chr. Weissii is somewhat sensitive to movement, and then often forms closely packed accumulations. Iron Bacteria in Hot Springs at Ikao.f — Prof. M. Miyoshi has found that the muddy deposit in the chalybeate hot springs of Ikao con- sists of the remains or skeletons of iron bacteria, and chemically of iron oxide. Microscopically it is distinguished from ferruginous earth by the fact that the latter is of a dirty brown hue, is finely granular, * Journ. Coll. Sci. Imp. Univ. Japan, x. (1897) pp. 143-73 (1 pi. and 26 figs.). f Tom. cit., pp. 139-42. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 425 easily suspended in water, and sediments with difficulty ; the bacterial deposit being homogeneous, of a pale yellow colour, and of a fleecy- mucoid character. Microscopically the mud is seen to consist of bac- terial cells, from 0 • 5-1 //, in diameter, straight or curved, of variable length, and of variable aggregation. The bacteria appear to have much in common with Leptothrix ochracea . The action of micro-chemical reagents (HC1 and ferrocyanide of potassium) seems to indicate that the iron oxide is deposited not merely on the bacterial cells, but in their substance, and consequently that the muddy deposit is of purely bacterial origin. Ginger-beer Plant.* * * § — From fresh observations, Prof. H. Marshall Ward has now como to the conclusion that there are several distinct varieties of kephir and of other ginger-beer plants. In all cases the schizomycete Bacterium vermiforme appears to be concerned, but asso- ciated with different yeasts. An organism closely resembling kephir wras found to be an aerobic bacterium capable of fermenting sugar to carbonic acid and some other organic acid. Very little yeast was pre- sent, and that apparently did not increase. Bacterial Disease of Cotton.j — Mr. J. M. Stedman ascribes a disease which attacks the capsules of the cotton-plant to an undescribed microbe which he names Bacillus gossypinus sp. n. It consists of short straight rods abruptly rounded at the ends, 1*5 by 0*75/*, usually solitary, sometimes in pairs, less often in chains of 3 or 4. The bacillus is motile, aerobic, forms spores, and does not liquefy gelatin. The dis- ease does not make itself evident by external brown patches, as is the case with the anthracnosc produced by Colletotrichum Gossypii. Influence of the Rontgen Rays on Bacteria. if — Prof. G. Sormani experimented with sixteen species of bacteria, most of which were patho- genic, for the purpose of ascertaining the effect of the X-rays. Broth cultures were exposed to the influence of the rays at a distance of 2-5 centimetres for periods varying from one to nine hours. After the pro- cedure, the cultures were transplanted into new media, whereon they developed with quite normal characters. The pathogenic action of the exposed cultures was also found to be undiminished. The author con- cluded that the X-rays have no sensible effect on the cultural and patho- genic characters of the bacteria employed. Resorption of Bacteria after Local Infection.§ — Dr. J. Halban made experiments for the purpose of ascertaining how long bacteria take to reach the nearest lymphatic glands, and the circulating blood from the inoculation site, and also for ascertaining what histological changes arise in the lymphatic glands after the resorption of the bacteria. A general answer is returned to the first question. The time taken by the different species of bacteria to reach the nearest lymphatic glands varies with the bactericidal power of the alexins, being slower when the power is strong and quicker when it is weak. The time * Ann. Bot., xi. (1897) pp. 341-4. Cf. this Journal, 1892, p. 524. t Agric. Exp. Stat., Auburn, Alabama, Bull. No. 55, 12 pp. and 1 pi. See Bot. Centralbl., lxx. (1897) p. 35. X Rendiconti Reale 1st. Lombardo, xxix. (1896) pp. 517-20. § S.B. K. Akad. Wiss. Wien, cv. (1896) pp. 349-452 (2 pis.). 426 SUMMARY OP CURRENT RESEARCHES RELATING TO bacteria take to reach the blood is also very variable, though it was fairly well ascertained that an infection of a bleeding wound may remain local for about 2^ hours (anthrax). The chief histological changes were haemorrhage, exudation of fibrin, hyperplasia, presence of leucocytes, pus-cells, and bacteria. Excretion of Bacteria by the Animal Body.* * * § — Dr. F. J. Cotton made a series of experiments on animals for the purpose of ascertaining under what conditions, at what time, and in what quantity, bacteria are excreted in the bile, and by the intestine after intravenous injection. The animals employed were rabbits, and the bacteria selected were B. anthracis, subtilis, prodigiosus , and Pneumoniae , Staphylococcus aureus , and Diplococcus pneumoniae. Suspensions in bouillon of fresh agar cultures were injected into an ear vein, and the animals killed at various intervals. Cultivations were then made from the different secretions and viscera. From the results of his experiments the author concludes that certain bacteria, if present in large numbers in the blood, may be excreted by the bile without any perceptible changes having previously taken place in the liver or bile ducts, but the presence of large numbers of bacteria in the bile is almost necessarily associated with pathological changes. So too with regard to the intestine and the urine, the presence of bacteria in their case is evidence of pathological changes in the intestine or in the urinary tract. Pathogenic Water Bacteria.^ — The most prominent feature of Prof. IT. M. Ward’s report on the bacterial flora of the Thames is that many river bacteria are pathogenic or become so on culture, and that patho- genicity, like other characters, is variable. The author’s work includes the consideration of some eighty forms, which for investigation purposes are aggregated into groups. Each of the groups contains a type, which is regarded by the author as probably a species of which the other forms included are varieties. The massing into groups was the outcome of finding that slight extrinsic and intrinsic changes, i.e. alterations in the cell or its environment, wrere immediately followed by distinct and often marked variations in the colonies and inferentially in the individual cells, and that characters derived from the behaviour of -colonies are not sufficient for the determination of species. The report also points out that the effects of definite changes in the environment on the media and on the growing organism are important, and that this importance is not sufficiently recognised. Micrococci of Malaria.* — Dr. L. Facciola describes appearances which he has observed in the blood of malarious persons, and depicts these appearances very copiously. The bodies observed vary consider- ably in size and shape, and from the illustrations have nothing in common with Micrococci except the name. Plague Bacillus.§ — From observations made during an epidemic of plague in Formosa, Prof. M. Ogata thus summarises his results. In the lymphatic glands of plague patients, and in the organs and blood of * SB. K. Akad. Wiss. Wien, cv. (1896) pp. 453-512. + Proc. Hoy. Soc., lxi. (1897) pp. 415-23. % Atti Soc. Toscana Sci. Nat., xv. (1897) pp. 220-9 (84 figs.). § Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 769-77. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 427 plague corpses, there can be constantly found a bacillus which reproduces in animals a disease closely resembling plague. In the blood of plague- patients the presence of the plague bacillus is not constant. It may be often found in the urine and bile of plague corpses. Insects, such as the flea and mosquito, are capable of transporting it. It is constantly pre- sent in the blood and viscera of rats naturally or artificially infected with plague. Fleas found on plague rats often contain virulent plague bacilli. The blood, lymphatic glands, and other organs of plague patients and corpses, may contain various other bacteria as well as plague bacillus. The plague bacillus is but little resistant to antiseptics such as 5 per cent, carbolic acid, one per thousand sublimate, or even strong lime-water. Direct sunlight killed an agar-culture after an exposure of four hours. Inoculation experiments on animals seemed to show that the soil of plague-districts was not infected. Spirillum Maasei.* — Dr. H. J. van’t Hoff isolated from the Rotterdam Waterworks a choleroid organism which has the following characters : — It has two or more turns ; it liquefies gelatin with extraordinary rapidity, and the colonies are round and transparent. Milk is not coagulated, nor bouillon acidified. On liquid medium a scum is formed sooner or later. There is no gas production. The indol reaction is quite like that of cholera. The spirilla are short and thick, 1-1*15 fi ; these have one or two flagella, and are mobile. The spirillum is virulent to guinea-pigs. Septicaemia of Calves.f — Prof. M. Thomassen describes a new sep- ticaemia of calves which is associated with nephritis and urocystitis. The disease, which lasts about five or six days, is marked by considerable enlargement of the spleen, and by parenchymatous nephritis and cystitis. From the blood, the peritoneal fluid, and from various organs, a bacillus closely resembling in appearance the bacillus of typhoid or B. col . com. was isolated. From the latter it is distinguished by its great mobility, by its moist-looking growth on potato, by its slow growth on gelatin, by almost negative production of indol and carbonic acid, by its inability to ferment lactose and to coagulate milk, and by the absence of a dis- agreeable odour when cultivated in pepton-bouillon or on gelatin. From the bacillus of typhoid it is distinguished by the serum reaction ; for although typhoid serum agglutinates the bacillus of calves’ bacteriseraia, the agglutination effect is much less strongly marked, and is different in character. Two Chromogenic Microbes from the Mouth.J— Dr. Arpad R. v. Dobrzyniecki describes two micro-organisms found in the mouth: — (1) Micrococcus latericeus is about 1 yu, in diameter, is devoid of move- ment, and has no special arrangement. It grows slowly in bouillon, the medium becoming cloudy, and after 2—3 days a granular brick-red sediment appears at the bottom of the culture-vessel. On gelatin plates rose-coloured colonies develop. The gelatin is not liquefied. On agar a similar growth develops. The micrococcus is easily stained, and is not pathogenic. (2) Bacillus luteus is found in carious teeth. It is a * Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 797-8. t Aim. Inst. Pasteur, xi. (1897) pp. 523-40. X Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 833-5. 428 SUMMARY OF CURRENT RESEARCHES RELATING TO rodlet about 1*5^ long. In bouillon a yellow deposit is noticeable in 2-3 days. On gelatin wbicb is not liquefied the growth is yellow. On agar, albumen, and potato the growth is also yellow. The bacillus is easily stained, and is not pathogenic to animals. Micrococcus Ghadiallii.* — Dr. Ghadially has discovered a coccus which has the power of slowly destroying the enteric fever microbe in water and milk, and to some extent in bouillon. It also seems to have some power of destroying the Bacillus coli communis in water. The enteric fever microbe in water and milk died out within 24 hours after inoculation with M. Ghadiallii. Pains were taken in these experiments to acclimatise the enteric microbes before the micrococcus was added. Agglutination of Bacillus typhosus by Chemical Substances.f — M. E. Malvoz records some interesting experiments made with certain chemical substances on cultures of the bacillus of typhoid. Formalin, corrosive sublimate, oxygenated water, and alcohol, all produce well marked agglutination. With these substances concentra- tion is an important feature, while with safranin and vesuvin the reaction obtains with very dilute solutions, one per thousand being sufficient to produce clumping of the bacteria. Salicylic acid and per- manganate of potash were found to possess a slight agglutinating action. Caustic soda and ammonia mixed with a hard water have strongly agglutinating action, but not when mixed with distilled water. As might be expected, the addition of a little safranin solution to. a normal serum not possessing an agglutinating power readily imparts this property. The agglutinating property of these chemical substances was used by the author to distinguish the typhoid bacillus from B. coli communis. For this purpose formalin is especially effective ; for with the typhoid cultures the bacilli are agglutinated into clumps, while the colon bacilli are immobilised and isolated. Safranin gives very similar results. From further experiments made after washing off the outer layers of the bacteria, it would seem that the ciliated envelope is re- sponsible for the phenomenon of agglutination. Bacteriology of Ambergris.^ — Ambergris, says M. H. Beauregard, is an intestinal concretion developed in the rectum of the Cachalot, and is composed of ambrein crystals, mixed with a greater or less quantity of black pigment. When fresh, the mass is rather soft, and has a highly stercoraceous odour which disappears with lapse of time. From one of the nuclei, of which these intestinal calculi are aggregations, cultiva- tions on various media were made. Two tubes were fertile, one of gelose and one of bouillon. From these cultures was isolated a microbe, morphologically closely resembling the bacillus of cholera. This micro-organism, Spirillum recti Physeteris , has the following general characters. The microbe is extremely polymorphic, presenting itself as straight rodlets or spirals according to the cultivation medium. It is extremely mobile. It varies in length from 1*4 to 4 • 2 /*, and in breadth from 0*5 to 0*8 /x. It is easily stained, but is decolorised by Gram’s method. * Brit. Med. Journ., 1897, ii. pp. 418-9. f Ann. Inst. Pasteur, xi. (1897) pp. 582-90. X Comptes Rendus, cxxv. (1897) pp. 254-6. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 429 The optimum temperature is about 37°, and in bouillon it forms a pellicle on the surface of the medium. The existence of this microbe affords some support to the notion that calculi may have a microbic origin. Fate of the Tetanus Toxin.* — Dr. A. Marie, after pointing out that if tetanus toxin be injected into a vein it requires a dose 7 or 8 times greater to kill an animal than if injected under the skin, explains that this toxin is easily and effectively carried to the central nervous system along nerve-paths. If injected directly into the circulation, the poison is materially altered by the cells and plasma of the blood. Experi- ments made for the purpose of discovering what becomes of tetanus toxin, show that the toxin, when injected into animals, remains in their blood for a variable time, and when the time is past, inoculations from the organs and from secretions of glands do not excite tetanus. The author mentions that frogs were easily tetanised during winter when the water oscillated between 18° and 18° C., by injecting the toxin or cultures. With 0*5 milligram, the symptoms appear between the 18th and 25th day, and with 6 milligrams on the 9th to 15th day. Staphylococcus hsemorrhagicus.-f — Dr. E. Klein describes a coccus pathogenic to man and animals, isolated from a vesicular eruption, on the hands of persons who had been skinning sheep dead of “ gargle ” a few days after lambing. The coccus belongs to the group which comprises Stapli. pyogenes aureus ; it is 0 • 4-0 • 6 //, in diameter, and grows freely on all the ordinary media. It slowly liquefies gelatin, and coagulates milk in about a week. Alkaline broth rapidly becomes turbid, aud its reac- tion acid in from 2 to 4 days. On agar and gelatin the growth is whitish, becoming somewhat yellow with age and increasing size. Cultures of this coccus -were virulent to guinea-pigs and sheep, the chief morbid phenomena being a haemorrhagic oedema of the subcutaneous and mus- cular tissues, and the presence of sanguinolent fluid in the peritoneal sac. Inoculations of the agar culture which proved fatal to sheep gave positive results on the author’s hand. Nitroso-Bacterium with new Growth-Form.:-: — Dr. W. Kullmann describes a nitrite-forming bacterium which, cultivated on nitrite-agar, presents itself as thick, anisodiametric rodlets. It is devoid of move- ment and of flagella. Nitroso-hacterium foi'mse novse, when grown on gelatin, develops into filaments of greater or less length. The individual links are short rodlets with very marked polar staining, and much the same size as when grown on agar. If transferred to nitrite-agar or to liquid inor- ganic media, there appeared in the course of a few days forms exhibiting simple and branched processes. When retransferred to ordinary media the rodlet shapes reappeared. The processes, after an incubation period of four days at 37°, were observed to develop from one pole, the other pole becoming expanded or bulbous. At 22° the processes appeared on the sixth day. On the solid medium the processes were simple, in the liquid nutrient inorganic fluid only were they branched. That these * Arm. Inst. Pasteur, xi. (1897) pp. 591-9. t Brit. Med. Journ., 1897, ii. pp. 385-7. X Centralbl. Bakt. u. Par., 2te Abt., iii. (1897) pp. 228-31 (1 fig.). 430 SUMMARY OF CURRENT RESEARCHES RELATING TO processes are not flagella is obvious from their being easily stained ; that the organisms are non-motile, from the branchings, and also from their being of the same thickness throughout. It is suggested that these outgrowths are to be regarded in the light of organs for taking up oxygen, which thus aid in the nitrification process. Pseudo-Tuberculosis Hominis Streptotricha.* — Dr. S. Flexner gives a brief account of a bacteriological find in the lungs and peritoneum of a negro who died with symptoms of tuberculosis. The lungs were con- solidated and breaking down ; while on the peritoneum, in the liver and in the spleen were nodules resembling tubercles. Cover-glass prepara- tions showed no microbes resembling the Bacillus tuberculosis in their morphology. Cultures from different sites were negative, both as regards B. tuberculosis and the fungus found in the lungs. This organism was a branching one, often occurring in clumps or in convoluted masses among which no ordinary bacillary forms were discovered. From the lesions in the lungs and peritoneum, and from the intimate relation of the masses of Streptothrix to the pathological process, and also from the symptoms resembling those of phthisis florida, the organism is designated pseudo- tuberculosis hominis Streptotricha. Flavour-producing Micrococcus of Butter.f — Mr. S. C. Keith has isolated a micrococcus which produces a decided butter flavour and aroma when grown in milk or cream, and to this new species the name M. butyri-aromafaciens is given. The general characters of this coccus are that it occurs usually in pairs ; it is 0 • 5-1 p ; is not motile ; grows'well at 37° and at 20° ; is aerobic and liquefies gelatin slowly. On agar the growth is white and abundant. It does not coagulate milk, but imparts to it a slightly sourish pleasantly aromatic buttery flavour. The reaction of the milk is acid. It does not produce gas in Smith’s medium ; it does not grow well on potato ; it renders bouillon turbid, forming at 37° a surface growth. It reduces nitrates to nitrites. * Bull. Johns Hopkins Hosp., viii. (1897) pp. 128-9. t Technology Quarterly, x. (1897) pp. 247-8 (2 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 431 MICROSCOPY. A. Instruments, Accessories, &c.* Cl) Stands. Preparation and Horizontal Binocular Microscope.^ — Drs. L. Driiner and H. Braus describe an improved form of their binocular Microscope which has been especially useful for the dissection of nerves and muscles. The present improved stand (fig. 32), also made by Zeiss, enables the optical portion of the instrument to be placed in any desired position, this being for the purpose of facilitating the dissection of large surfaces, and, when the Microscope is placed horizontally, for observing the movements of small organisms through the vertical sides of aquaria. The optical portion may be moved with respect to the fork h by the rack and pinion r. The forks h and Ji are connected by a ball-joint I supplied with the necessary clamps ; the whole of this rotates with the collar li' about the horizontal rod /. This rod has a longitudinal motion * This subdivision contains (1) Stands ; (2) Eye-pieces and Objectives ; (3) Illu- minating and other Apparatus ; (4) Photomicrography ; (5) Microscopical Opt.ic6 and Manipulation ; (6) Miscellaneous. f Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 5-10 (2 figs.), p. 580. 1897 Cf. this Journal, 1895, 9 H 432 SUMMARY OF CURRENT RESEARCHES RELATING TO by means of the rack and pinion g , a vertical motion by tbe rack and pinion c, and it can be rotated in a horizontal plane with the collar d. The two erecting oculars and o2 are carried eccentrically, so that they can be accommodated to the distance between the eyes. The two objectives slide into grooves t. With the various oculars and objectives supplied with the instrument, amplifications of 6 • 5 to 48 are obtained. For use as a monocular, one of the tubes may be brought parallel to the rack by means of the turn-plate q. New Stand.* — Herr C. Reichert describes the new stand (No. VII 6) shown in fig. 33, which forms a cheap instrument for mineralogical and * Zeitschr. f. angew. Mikr., iii. (1897) pp. 74-5 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 433 geological purposes. The foot and column are east in one piece, so that the instrument can safely be held and carried by the upper portion. Roberval’s micrometer-screw is used for the fine adjustment, this being an advantage in small, though not in large, stands. The usual acces- sories for parallel and convergent polarised light are added. Method of Using the Microscope.* — Mr. N. A. Cobb describes, in the following terms, an apparatus which he has found useful in the application of the Microscope to agricultural inquiries: — “ The apparatus I have to describe has been so very useful to me that I cannot but think it will be also useful to others in this and other countries, engaged as I am on the various scientific problems presented by agriculture ; and if it turns out useful to them, even the farmer, who looks upon this technical article as of no service to him, will — whether he knows it or not— be indirectly benefited. “ This method of mounting and using a Microscope is one that has been gradually perfected through almost daily use since 1888. I have frequently been asked to publish the details, and have so far refrained from doing so only because I found that on each new Microscope mounted I was enabled to make a number of improvements ; and so long as this was the case, any description would soon be antiquated, and so become — to me, at least — only a source of annoyance. On no less than ten separate occasions has this device been remodelled to suit differing cir- cumstances, and it now stands in five laboratories under my supervision, viz. Sydney, Moss Yale, Wagga, Bathurst, and Pymble. “ The following is a key to the illustration (fig. 34) a a a, architrave of a window facing the sun. bbb, 1/4-in. runners, 4 in. wide, in which the blind d slides. c c, runners for the arm j, which carries the camera m. d , perfectly opaque blind, made of American leather or enamelled cloth running on a spring roller at the top of the window. By raising this blind the whole apparatus may be flooded with sunlight if necessary. e, a 1/4-in. board, 8 in. wide, hanging in an inch-deep slot in the board/, and riveted to the blind d, and hence rising and lowering with the blind. This board e slides in the runners bbb. f f, an inch board, 8 in. wide, fitted to the side of the window and receiving the board e, into a median slot 1/4 in. -wide, and 1 in. deep in its upper edge. {/, two sliding pieces of thin ebonite, placed one behind the other, each with a diamond-shaped opening cut out in the middle. By sliding these ebonite shutters, the opening h can be made of various sizes. i i, the runners in which the two ebonites g slide. Behind the ebonites an elongated opening is cut in the board e , and this opening has a ground glass sliding over it in runners similar to ii, but fastened to the back side of e. All these latter appliances are for the purpose of varying the amount and character of the light coming through the diamond- shaped opening h. j , wooden arm,. 1 in. thick and 3 in. wide, carrying the micro-camera m, and sliding in the ways c c, capable of being clamped by the set-screws w. Any position of j may be recorded by means of scales marked on c c. 7;, photographic plate-holder, half-plate size, as used on an ordinary tripod camera. 7, frame iuto which the slide It is pushed, in construction similar to the back of an ordinary tripod camera. in, leather bellows of micro-camera, capable of extension to four or five feet. * Reprint from Agric. Gaz. N.S. Wales, March 1897. 2 H 2 434 SUMMARY OF CURRENT RESEARCHES RELATING TO ??, wooden front or head of camera, into which the barrel of the Micro- scope fits. This head is hollowed out, and carries a light ebonite shutter, actuated from the outside, by means of which the exposures are made. The wire lever actuating this shutter is shown as a dotted white line near n (see also fig. 35). o, mirror of the Abbe camera lucida. 2>, barrel of the Microscope. q q, vertically sliding tables, the right-hand one being used as a drawing- board when the camera lucida is in use. Being adjustable, various magnifications can be secured. The higher q is placed the less magnification the drawing will show. A scale drawn on the archi- traves enables any position of q to be registered. The left-hand table is similarly adjustable, and is usually kept on a level with the Microscope stage. Both these sliding tables are cut away to suit the observer’s body resting on the stool v. Both are braced so as to be quite rigid under the weight of the arms in drawing, &c. r, head into which the foot of the Microscope is firmly clamped by means of easily removable wooden wedges. s , pillar bearing the Microscope, preferably of iron and planted in cement beneath the building, and coming through the floor without contact with the building. If this is not feasible, r may be fixed to the window-sill. In three of my laboratories the ways c c are fixed to iron or wooden beams, also planted in the earth and coming through the floor without contact, thus making a very perfect arrangement for long photographic exposures with high powers where all tremor must be avoided. t f, halves of wooden hand-clamps of large size (15 in. long and 2£ in. square), grooved to slide in the ways u u, and carrying the well-braced tables q q. u u, two wooden table-ways, firmly fastened to the side of the building. v , stool. ic, set-screw, to clamp the camera in position. x x , four set-screws, to clamp the tables q q in position. y, opaque cloth, sewed on to a rectangular opening cut in the board / to admit the light to the mirror of the Microscope. Slots to hold coloured glasses are arranged on the back side of this opening, to furnish mono- chromatic light for photography, &c. The various substage adjust- ments can be worked through the cloth, which, however, can be lifted in a second when necessary. “ After having made the different features of the drawing (fig. 34) clear, it will only remain to explain some of the advantages of this system of utilising the Microscope. Having used the Microscope for purposes of investigation almost daily for nearly twenty-five years, I feel justified in calling particular attention to opinions based on such extensive experience. “ The apparatus is adapted to the best of all lights — daylight. The perfection of the image as formed on the retina of the eye is very great ; for if the room be darkened, and the blind d be closed, no light but that from the Microscope enters the eye. Few, even among experts, according to my observations, realise the evil effects of extraneous light when observing with the Microscope. Those who do realise this evil are usually found advocating the use of artificial light by night so as to avoid the evil. Here is a way to avoid it and still keep to the use of daylight. It need scarcely be pointed out that the cloth y is for the purpose of excluding extraneous light. “ The window faces the sun, so that, whenever it is desired, by simply raising the blind d , sunlight can he obtained on the top of the stage as well as under it. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 435 “ The whole apparatus is quite rigid. The arrangement for drawing with the camera lucida is of a high degree of perfection. I am often struck with the complication of the Fig. 34. Perspective view of Microscope mounted for purposes of investigation by daylight. Dimensions may be gauged by the diameter of the top of the stool v , which is 1 foot. various more or less expensive devices (always more or less imperfect too) attached to the camera lucida as now made, and having for their object the graduation of the light, so as to equalise the lights coming 436 SUMMARY OP CURRENT RESEARCHES RELATING TO from the object and the drawing-paper respectively. This object is usually accomplished by inserting between the drawing-paper and the eye a glass having the correct neutral tint. It is usually found that the exact tint required cannot be obtained, either because the properly tinted glass has been lost or broken, or never existed. In any case, such glasses are in the way, and can only have been regarded as a necessary evil. In the system here described, the light coming through the Microscope is first graduated so as to be as perfect as possible, then the diamond-shaped opening h is set so as to exactly equalise the lights coming from the Microscope and from the drawing-paper located on the circle under the pencil shown in the illustration. This can be done in an instant and with the utmost precision. The ground glass behind h serves to destroy the image of outside objects which are formed when the aperture li is reduced m size. Fig. 35. The difficulty of using the camera lucida with very high powers is well known. With this system there is no difficulty ; whatever cah be clearly seen can be drawn. “ When the left-hand table q is arranged on a level with the Microscope stage, the moving of objects on to and off the stage is conveniently accomplished. “ The sliding adjustment of the drawing-board or table (right- hand q) will commend itself at once to anyone who has used a camera lucida. Already a number of patents exist on this head, but all that I have seen are lack- ing in stability and convenience. Here, however, the artist may lie stretched at ease, and, having so adjusted the drawing-board as to secure the desired magnification, can work with comfort and with great precision. “ The nice working of the fine adjustment is facilitated by the fact that the ball of the hand may at the same time rest on the table. “ The Microscope can be clamped in position, and is movable within limits. “ The photographic camera is in readiness for instant use, and is as rigid as possible. Being arranged on a vertical system, it is most con- venient. Few, I imagine, having once fairly tried a good vertical system, will ever revert to any other. Its advantages are obvious. For instance, the stage remaining horizontal, the object does not tend to float and get out of focus ; liquid backing on the plate does not flow ; the focusing can be most easily and accurately done, especially when the ground glass is dispensed with, and a lens used instead ; the bellows never bothers by sagging when long drawn out ; and so forth, and so forth. My whole apparatus is made as low as possible, so that in focusing on the ground at Z it is only necessary to stand up. If the camera has to be ex- Section of heart of Microscope-camera, one- lialf size — a, vulcanite shutter; 6, arm or lever for opening aud shutting the shutter a (this arm is outside the head) ; c, slot into which a is set ; d, rabbited opening into wrhieh the draw-tube of the Microscope fits in a light-tight manner. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 437 tended to 5 feet, it will be necessary to provide steps, as l thus comes up above the bead of the standing operator. The focusing lens can rest on the ground glass, or swing on a vertical pivot fastened into the frame l , or be carried on a rack-stand resting near h. “ For long focusing, when it is inconvenient to reach the fine adjust- ment with the hand, I use a stick, the end of which carries a piece of metal Fig. 36. Back view of white screen having universal movements; d,e,f, and h, same as in fig. 34 — that is: d, opaque blind ; e, 1/4 in. board, 8 in. wide, attached to d, and rising and falling with it ; /, 1 in. board, 8 in. wide, top of which is slotted to receive e ; h , the same diamond-shaped opening shown in fig. 34 ; g, top of screen ; i, forked wrought-iron spindle, shown black, except where it enters the post — the dots show its continuation ; l /, uprights imbedded in the ground and passing up into the building without touching it, and supporting the Microscope-camera above the operator’s head ; m, pillar supporting the Microscope, imbedded in the ground, and passing up into the building without touching it. The cords and pulleys are for the purpose of moving the screen from inside the building. The small mirror mentioned in the text is placed on the front of the screen near g. that fits into a slot filed in the top of the fine adjustment screw. When the adjustment is secured, the stick is removed. This convenient arrange- ment has often enabled me to take photomicrographs with great rapidity. “ The pillar e forms a model support for a dissecting stand, the tables q q being then placed at equal heights to serve as arm-rests. “ The light is obtained from a white screen, having universal move- 438 SUMMARY OF CURRENT RESEARCHES RELATING TO ments, placed outside in tlie sunlight, and workable from the interior by means of cords and pulleys. The screen is a broad frame covered with bleached sheeting. On one end of the screen is a small mirror, so fastened as to indicate, by the sun’s reflection, when the screen is re- flecting the maximum amount of sunlight. This light reflected from the screen is superior to the proverbial white cloud, and eclipses any artificial light. “ I feel sure that, in the right hands, the appliances I have here de- scribed, if patented, could be made a source of profit ; and the moral right to so use them is hereby freely given to whomsoever chooses to accept. “ It is with much pleasure that I acknowledge the aid, during the last few years, of Mr. E. M. Grosse in executing a number of the details of this system of using the Microscope. The accompanying illustrations are from his hand.” (3) Illuminating' and other Apparatus. Projection Lantern.*— M. H. Mohlenbruck describes an ordinary form of projection lantern for showing microscopic preparations and photographs. Light-Filters and Colour-Screens. | — Dr. A. C. Stokes points out the unsatisfactory nature of the ordinary coloured glasses and fluid-cells. The best he has used is Clifford’s malachite-green screen, but for con- tinual use the light of this is trying to the eyes. For general use the author has a particular kind of blue glass (from Lovibond’s tintometer) coated with a layer of “Walpole green” cement; this is pleasanter to the eyes, but does not give so good a definition as the Clifford screen. Simple Machine for Micrometer Rulings.} — Mr. D. W. .Smith has devised a simple inexpensive machine for producing fine rulings, up to Fig. 37. thirty or forty thousand to the inch, on glass. The micrometer-screw A (fig. 37), with graduated head E, imparts a longitudinal motion to a metal wedge B, which, for each turn of the screw, gives a lateral motion * Arch. Sci. Pliys. et Nat., iii. (1897) pp. 590-3. f Journ. New York Micr. Soc., xiii. (1897) pp. 5G-63. X Tom. cit., pp. 53-5 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 439 of 1/1000 in. to tlie metal block C. The diamond-carrier D, which is worked to and fro by hand, is kept in contact with the block C by springs. The working surfaces are formed by slips of plate-glass. The necessary clamps and springs are not represented in the figure. Covered Rectangular Motions for Stages.* — Dr. R. Brauns de- scribes an improvement on the usual rectangular stage-motions when used Fig. 38. p7 p xsl in connection with a graduated circle. The ordinary forms, in which the rectangular motions are above the circle, have the disadvantage of the graduations being often partly hidden and shadowed by the screws and slides ; the mechanism is further unprotected from dust and reagents. To the base-plate of the circle K (fig. 38) eight guides S are fixed, and between these the four prisms P move. To the last are fixed the * Zeitschr. f.^wiss. Mikr., xiv. (1897) pp. 11-3 (2 figs.). 440 SUMMARY OF CURRENT RESEARCHES RELATING TO it the rectangular movements are im- parted by the micrometer-screws M which work in two of the prisms P. All this mechanism lies within the body of the graduated circle, and is protected from dust by the annulus D. The eccentric E clamps the circle, and B is the fine-adjustment of the same. The same arrangement can also be used with non-rotating stages. It is made by P. Brunnee, of the firm Yoigt and Hochgesang, of Gottingen. Lens-Support for Examining Seeds * — Herr C. Reichert briefly describes the lens-support shown in fig. 40, which has been made according to the designs of Dr. von Weinzierl for the examination of seeds. The arms c and c', carrying low-power lenses, are capable of horizontal and vertical movements, and are supported on a heavy base. The lens-support shown in fig. 41 is mentioned here. The lens slip * Zeitschr. f. angew. Mikr., iii. (1897) pp. 72-3 (2 figs.). Fig. 41. four prisms P' which move between the prismatic edges of the frame R and the four guides S'. The frame R is fixed to the stage T, and to Fig. 40. R^iCHtRT,.' WIEN. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 441 easily into a sleeve which is carried on the movable arm D, this being fixed, with the object-clips, to the ebonite hand-frame H. Knife-Holder for Microtomes.* — Dr. R. Hesse describes a knife- holder (fig. 42), with which it is possible to vary the inclination of the knife from the horizontal position. The sliding arc has a radius of 15 cm. The graduations at the side are millimetres, 1 mm. correspond- ing to a movement of O’ 8° of the knife. The holder is made by R. Jung, of Heidelberg. Fig. 42. (4) Photomicrography. Systematic Photomicrography.^ — Mr. J. B. Shearer points out that the time of exposures, &c., in photomicrography depends too often on guess-work, and suggests a systematic keeping of records of exposures which have been successful, in order to serve as a guide in future cases where the conditions are more or less similar. For this purpose he has had printed a book of forms to be filled in with the details as to lenses used, distances of the light and photographic plate, time of exposure, colour of object, &c. The apparatus used by the author consists of a turntable L (fig. 43) carrying the Microscope, Welsbach lamp, and bull’s-eye condenser. After the light, &c., has been arranged, the turntable is swung round, and the Microscope-tube is inserted in the camera front. The image is focused from the back of the camera by a rod D, which passes the whole length of the camera-bed and actuates a band passing over the fine adjustment of the Microscope. For the illumination of opaque objects, the lamp can be moved with respect to the Microscope. An arrangement, in * Zeitsclir. f. wiss. Mikr., xiv. (1897) pp. 13-5 (1 fig.), f Trans. Amer. Micr. Soc., xviii. (1897) pp. 117-130 (5 pis.). 442 SUMMARY OF CURRENT RESEARCHES RELATING TO which the body of the Microscope is vertical, for photographing objects in liquids, is figured. The procedure of developing the photographic plates is described. Fig. 43. B. Technique.* (1) Collecting- Objects, including- Culture Processes. Plankton-Methods. — Prof. J. Frenzel j discusses at some length the merits and demerits of the silk-gauze net. Even the details of the block- ing of the gauze come to have importance in exact quantitative estimates of the Plankton. He recommends repeated use of hot water for cleaning the net, which he regards as fully useable when it remains constant in hot water. Prof. Y. Hensen t also discusses the use of the silk-gauze net. To free it from adhering particles which tend to close the pores, the best plan is to rub it under water with a bath-sponge. This is much better than boiling, which Frenzel recommended. Medium for differentiating the Bacillus typhosus from Bacterium coli commune.§ — Dr. K. Kashida recommends the following medium for easily distinguishing between Bacterium coli commune and the bacillus * This subdivision cod tains (1) Collecting Objects, including Culture Pro- cesses ; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; (4) Staining and Injecting ; (5) Mounting, including slides, preservative fluids, &c. ; ^ M i cnol Ion onn a t Biol. Centralbl., xvii. (1897) pp. 364-71. % Tom. cit., pp. 540-42. § Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 802-4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 443 of typhoid fever : — A 1 • 5 per cent, agar solution, made by dissolving the agar in bouillon, is first prepared. This is then cleared up, strained, and filtered. To the filtrate are added 2 per cent, lactose, 1 per cent, urea, and 30 per cent, litmus tincture. This is then distributed into test- tubes (10 ccm.) and steam sterilised for 10-20 miuutes. Cultivated in this medium, the difference as to production of acid between the two bacteria is rendered very striking. After inoculation, the medium may be poured into capsules and incubated at 37°. In from 16-18 hours, coli turns the blue colour of the medium quite red, the reaction of the condensation water being also acid. After 24 hours the medium again becomes blue, owing to ammoniacal decomposition of the urea. The colonies also turn blue, and the presence of ammonia can easily be ren- dered evident by touching the medium with a glass rod moistened with hydrochloric acid. When inoculated with typhoid bacilli there is no reaction to litmus, and the blue colour remains unchanged for 72 hours or more. The differences between the two may be rendered strikingly obvious by sowing them side by side in the same capsule. Cultivating Gonococcus. — Dr. J. de Christmas,* in an interesting communication on Gonococcus and gonotoxin, states that he has found rabbit serum to be an excellent medium for the cultivation of this microbe, and that human albuminous fluids, such as blood-scrum, ascitic fluid, or pleuritic exudation, mixed with peptonised gelose in the pro- portion of two to one, give abundant cultures. The preference is giveu to ascitic fluid, which is easy to obtain and easy to sterilise, as it will stand, without coagulating, a higher degree of heat than blood-serum. The mixture with gelose is perfectly clear, and stroke cultivations in- cubated at 35° develop abundantly in 24 hours. The cultures, how- ever, die off in 3 or 4 days, and have, therefore, to be resown every 48 hours. This inconvenience is obviated by the use of coagulated rabbit serum, on which the microbe not only thrives freely but lives for at least 3 or 4 weeks. The difficulty in connection with rabbit serum is that it is obtainable only in small quantity, about 60 ccm. for one animal. For the study of gonotoxin such small amounts are quite insufficient, and the author used ascitic fluid mixed with peptonised bouillon in the proportion of 1 to 3. The bouillon was ordinary veal- bouillon, or was made with Liebig’s extract (0*5 grm. to the litre). The reaction of the medium should be slightly alkaline. Pure cultivations of Gonococcus were obtained by spreading a drop of the fresh pus upon the rabbit serum medium and incubating at 36^. In about 12 hours colonies of Gonococcus are well in advance of other organisms which may be present, and it is therefore quite easy, by once resowing, to obtain pure cultures. On rabbit serum the colonies are small, round, transparent, raised in the centre, isolated or confluent. Their chief characteristic is viscosity, which is well shown by the adhesion of the growth when touched with a platinum wire. The author explains the character of the distribution on cover-glass pre- parations as being due to this viscosity. It is also stated that the classic shape of Gonococcus always met with in pus is the least frequent in cultures. * Ann. Inst. Pasteur, xi. (1837) pp. 60D-.T3. 444 SUMMARY OF CURRENT RESEARCHES RELATING TO Dr. F. R. Hayner * has successfully cultivated Gonococcus from the fluids in joints and tendon-sheaths in the following media: — (1) Albuminous urine agar. Acid urine containing .0*05 albumen or more is allowed to stand for 24 hours, and then boiled. The pre- cipitate is then removed by filtration. The filtrate is again boiled, and agar, pepton, beef extract, and sodium chloride added in the pro- portions used for making ordinary agar. The reaction should be neutral or very slightly acid. The advantages of using albuminous urine are, firstly, that such urine contains albumens that are not coagu- lated by heat; and, secondly, the albumen that is coagulated acts as a clarifying agent in the removal of the salts that usually cause the cloudiness of the urine-agar. (2) An ordinary agar-tube was melted and cooled to 46° C., and then about 5 ccm. of human blood-serum added, making the proportion one- third blood-serum and two- thirds agar. The resulting medium, which was perfectly clear, was then inoculated with three loopfuls of fluid from a joint. The inoculated medium was poured into a Petri’s capsule and incubated at 37°. Colonies were observed after 48 hours. (3) Pig-foetus agar. This medium is prepared from fresh pig- foetuses not exceeding 5 cm. in length, and free from placenta and membranes. The foetuses are minced in a sausage machine, and then placed in an equal volume of distilled water, the mixture being allowed to macerate in a cool -place for from 6-12 hours. The fluid is then passed through a Chamberland filter under a presssure of 150-200 lbs. Two per cent, sterilised agar is then melted and cooled down to 40°, and to it one- third of its volume of foetus infusion is added. The tubes are then slanted. Protozoa Culture.! —Dr. F. Schardinger now uses a medium prepared in the following way : — To a suspension of about 30 grm. of hay in 1 litre of water, 1-1 • 5 grm. of powdered calcium hydrate are added, and, after having been well shaken, the mixture is incubated for 24-36 hours. The fluid is then filtered, and, the chalk having been precipitated with phosphoric acid, an equal quantity of meat infusion (made without pepton or salt) is added. The mixture is then alkalised with soda, and 1-1*5 per cent, of agar added. In this medium quite pure bacteria-free cultures of a Mycetozoon (Protomonas Spirogyrse Borzi) were obtained ; and, if gelatin be substituted for agar, the above described fluid serves well for the preparation of a cultivation medium suitable for bacteria cultures. (2) Preparing- Objects. Method for rapidly Examining for Bacteria in cover-glass pre- parations.:}:— Dr. D. Kischensky recommends the following method for examining for micro-organisms in pure cultures, and also in pus, blood, urinary sediment and faeces. A drop of phenol-fuchsin solution (10 drops to 10 ccm. of water) is placed on a cover-glass or slide and mixed with a minute quantity of the culture. The cover-glass is then gently warmed and the mixed drop spread all over so as to make a film which will dry * Bull. Johns Hopkins Hosp., viii. (1897) pp. 121-4. t Centralbl. Bald,, u. Par., l‘e Abt., xxii. (1897) pp. 3-5 (2 pis.). X Tom. cit , xxi. (1897) pp. 876-7. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 445 rapidly. By this procedure the bacteria are not only fixed, but deeply stained, and are quite ready for microscopical examination. For staining bacteria, in pus, faeces, and in urinary sediment, a better result is obtained by using a mixture of phenol-fuchsin and alcoholic solution of methylen- blue ; for thereby the nuclei of the cells and the bacteria are stained blue, while the cell-protoplasm and degenerated bacteria are stained red. Observing Nuclear Division in Equisetum and Chara. — Herr W. J. Y. Osterhout* finds Flemming’s mixture the best fixing material for observing the division of the nucleus in the spore-mother-cells of Equi- setum (see p. 416). Microtome-sections 5 /x thick were stained with safranin, gentian violet, and orange G, and mounted in Canada-balsam. The processes employed by Herr B. Debski f in observing the division of the nucleus in the vegetative cells and in the antheridial filaments of Chara (see p. 416) are described in the general sameness in the form and structure of the root in vascular plants. But in Areca Catechu , instead of the normal central stele of small diameter, four other types may be recognised, passing into one another by insensible gradations ; and a similar variation was observed also in other species of palm. Aerial roots are not infrequently poly- stelic in their thicker older parts ; and this difference in structure is due to a continuous change in the mode of differentiation of the apical meristem. The whole structure of the older aerial parts is such as to fit them for withstanding both pressure as props and tension as stays ; while the thinner subterranean parts are normal in conformity with the nor- mality of their functions and environment. In correlation with the bulk of these roots and the absence from them of pneumatodes, there is a conspicuous formation of pneumatophores. Wood of Pomeae and Amygdaleae.f — Dr. A. Burgerstein continues his observations on the structure of the wood of the Pomeae. On histo- logical grounds he advocates the retaining of Cotoneaster as a distinct genus, with which Pyracantha should not be associated. Mespilus also should not be united with Cratsegus. He enters into further details with respect to the structure of the wood of the Amygdaleae ( Prunus ), which differs from that of the Pomeae in no essential respect, though there are minor points, especially in the size of the vessels. Stem of the Sugar-Cane.§ — Herr A. Wielerhas examined the struc- ture of the stem in a number of different varieties of the sugar-cane, * Rev. Ge'n. de Bot. (Bonnier), ix. (1897) pp. 273-81. t Trans. Linn. Soc., v. (1896) pp. 275-86 (2 pis.). X SB. K. Akad. Wiss. Wien, cv. (1897) pp. 552-82. Cf. this Journal, 1896, p. 642. § Beitr. z. wiss. Bot. (Funfstiick), ii. (1897) pp. 141-65 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 547 especially in reference to the deposition of silica. In addition to the silicification of the walls of the epidermal cells, there occur in the epiderm special “ silica-cells,” the contents of which consist of a white mass of amorphous silica. Similar structures are found also in other grasses. The arrangement of the vascular bundles is the normal arrangement of Monocotyledons. Changes produced by Mycorhiza in the Cells of the Host-Plant.* * * § — MM. P. A. Dangeard and L. Armand have studied the effects produced on the tissues of the root of OpJirys aranifera by its endotrophic myco- rhiza. The filaments of the fungus penetrate the outer layers of cells, forming a ball in the cortical layers. They produce hypertrophy not only in the nucleus of the cells invaded, but in those also of adjoining cells. The cytoplasm of the cells attacked is gradually for the greater part consumed, 'while the nucleus remains active and intact. In the meantime the hyphae of the invading fungus become more or less disor- ganised, the small nuclei disappear, and a gummy exudation of an unknown character takes place. The nucleus of the host-cell, when attacked by the parasite, breaks up by fragmentation, the fragments pressing towards the surface of the ball by rhizopod-like prolongations. In the cells attacked there are two kinds of nucleus, some with ordinary reticulate structure and numerous vacuoles, others whose substance is finely punctated and without vacuoles. The nuclei of the invaded cells maintain their activity after the parasite has become completely disor- ganised. “ Sereh-”Disease of the Sugar-Cane, f — From a very exhaustive examination of a great number of varieties of the sugar-cane grown under many different conditions, Herr A.Wieler contests Janse’s theory that this wide-spread disease is due to stoppages in the conducting tissue caused by a parasitic schizomycete, Bacillus Sacchari, The gummy stoppages are of the same nature as those frequently found in other plants under healthy conditions, the gum being exuded into the vessels and intorcellular spaces from living cells. Schizomycetes are frequently present, but they are saprophytic, not parasitic, the result rather than the cause of disease. (4) Strupture of Org-ans, Inflorescence of Compositae.J — Herr A. Weisse finds the number of ray-flowers in the capitule of Composite to be subject to similar laws to those of the phyllotaxis of leaves. It is to a certain extent dependent on nutrition. Cohesion and Chorisis of Foliar Leaves.§ — According to observa- tions made by Herr G. W. Maly (chiefly on Weigelia rosea , which varies greatly in the number of parts of the flower), the normal number and arrangement of the vascular bundles is not departed from when either cohesion or chorisis takes place of members of the same whorl. A pri- mary vascular bundle enters into each member of the calycine, corolline, and staminal whorls ; those belonging to the sepals and stamens being * Le Botaniste (Dangeard), v. (1897) pp. 289-313 (8 figs.). J t Beitr. z. wiss. Bot. (Fiinfstuck), ii. (1897) pp. 29-140 (1 pi. and 23 figs.). X Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 453-83 (1 pi.). § SB. K. Akad. Wiss. Wien, cv. (1896) pp. 269-80 (2 pis.). 548 SUMMARY OF CURRENT RESEARCHES RELATING TO united for a considerable distance. The normal course of tbe bundles is maintained also in those flowers in which the number of parts of the flower is changed by cohesion or chorisis. Underground Fruits.* * * § — Sig. L. Pampaloni distinguishes two classes of plants which mature their fruits underground, amphicarpogenous and hypocarpogenous. In the former the flower is produced above-ground, and by some mechanical contrivance, the seed-vessel is buried in the soil before ripening ; in the latter the flowers as well as the seed-vessels are produced underground. To the former class belong Vida amplii- carpa , Lathyrus amphicarpus, Cardamine chenopodifolia , Polygala poly- gama, and Scrophularia arguta. Under the latter class he names thirteen species, belonging to seven different natural orders, viz. : — Amphicarpsea monoica , Arachis hypogsea, Astragalus hypogseus, Trifolium subterraneum, Trigonella Aschersoniana, Voandzeia subterranea (Leguminosae), Geococcus pusillus , Morisia hypogsea (Oruciferae), Cyclamen europseum (Primulaceae), Ohenia hypogsea (Nyctagineae), Nephrophyllum abyssinicum (Convolvu- laceae), Amphicarpum Purshii (Gramineae), and Ceratanthera Beaumetzii (Zingiberaceae). Fruit and Seed of Viscum.t — Herr G. Gjokic states that the threads of viscin which are formed when mistletoe berries are opened, are the membranes of cells which have been artificially drawn out. They give all the staining reactions of cellulose. The mucilage which surrounds the hypocotyl of the seedling is not identical with viscin ; it is stained yellow by chlor-zinc-iodide, and a beautiful red by ruthenium sesqui- cliloride. The lignified elements of the endocarp of Viscum album are reticulated cells and spiral vessels. The cells of the endocarp of tropical species of Viscum {articulatum and orientate) are neither lignified nor reticulately thickened. The exceptionally strong protection of the seeds of the mistletoe against evaporation, which enables them to germi- nate even in the exsiccator, depends on the development of a thick- walled cuticularised epiderm to the endosperm, covered by a thick coat of wax. The tropical species have no such contrivance. Fruit of Argania Sideroxylon.j: — According to M. M. Cornu, the seed and fruit of this species differ in several respects from those of typical Sapotaceae, both in the structure of the seed itself, and in the placentation. The seed contains a number of laticiferous cells, some of which branch in an arborescent manner, while some become sclerified. The mature seed is enclosed in a thick hard testa, resulting from a special layer of the ovary itself. Ovule and Seed of Hydnoraceae.§ — According to M. P. van Tieghem, the ovules of Prosopanche are not, as stated by de Bary, reduced to an embryo-sac imbedded directly in the parenchyme of the placenta, but resemble those of typical Hydnoraceae in being orthotropous and integu- mented. The embryo-sac, or mother-cell of the endosperm, contains an oosphere, two synergids, and three antipodals. The ovules are imbedded in, but not completely surrounded by, the placental parenchyme. The * Bull. Soc. Bot. I tal., 1897, pp. 190-3. t SB. K. Akad. Wiss. Wien, cv. (1896) pp. 447-64 (1 pi.), j Bull. Soc. Bot. France, xliv. (1897) pp. 181-7 (5 figs.). § Journ. de Bot. (Morot), xi. (1897) pp. 233-8 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 549 integument of the seed is differentiated into two layers. The develop- ment of the ovule into the seed presents this peculiarity in Prosopanche , that there is no absorption or digestion of any part of the ovule ; with the exception of the synergids and the antipodals, every constituent por- tion of the ovule is found in the mature seed. Seeds of the TTtriculariese.* * * § — Herr M. Merz has studied the deve- lopment of the seed in a number of tropical species of Uiricularia. No rudiment of a root could be detected in the embryo. The vascular bundles end in the placenta, not passing into the seed. The ordinary endosperm cell-division takes place in the central portion of the embryo- sac, while the two extremities swell up into haustoria, in which lie the enormously large endosperm-nuclei. The suspensor disappears after the abstriction of the haustorial portions of the embryo-sac. In the ripe seed the endosperm has entirely disappeared. There is only one integument. In the place of the chalaza are a number of cells which supply the upper swelling of the embryo-sac with nutritive material. The nucellus is completely absorbed during the development of the embryo-sac. The embryo of Pinguiculci vulgaris differs from that of TJtricularia in the absence of the constriction of the endosperm. Seed of Ceratonia siliqua.f — Dr. H. Marliere has studied the struc- ture and development of the remarkably thick membranes of the cells of the endosperm of the carob. He states that, at an early stage, the cell- wall is composed entirely of cellulose, with the exception of a very small quantity of pectic substance ; but that, after the secondary thickening has commenced, there are an outer and an inner layer of cellulose, and, between the two, a mucilaginous product of transformation still perme- ated by unchanged cellulose. When the seed is mature, this secondary membrane has become completely transformed into mucilage ; the cellu- lose can be detected only in the outermost tertiary layer. The mucilage is a product of the reduction of cellulose, the reticulate structure cha- racteristic of cell-walls being at least partially retained. In the coty- ledons the cell-walls are composed of cellulose, without any admixture of amyloid. The chemical reactions of the mucilage are given in detail. Pericarp of the B.ye.4 — Herr A. Gregory states that the well-known thickening of the transverse walls in the “ transverse cells ” of the peri- carp of the rye takes place only in the very last stage of ripening, and affords a practical test to distinguish ripe from unripe grains. In wheat and other cereals this thickening does not place. Assimilating Organs of Leguminosge.§ — Herr J. Eeinke has under- taken an exhaustive examination of the leaves and other assimilating organs in a large number of species belonging to the different tribes of Leguminosae. The ancestral type of leaf in the order was probably tri- foliolate, as in Trifolium ; but this became modified in a very large number * Flora, lxxxiv. (1897) Erganzbd., pp. G9-87 (34 figs.). t La Cellule, xiii. (1897) pp. 1-60 (2 pis.). X Beitr. z. wiss. Bot. (Fiinfstuck), ii. (1897) pp. 165-8. § Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 1-70, 528-614 (96 figs.). 550 SUMMARY OF CURRENT RESEARCHES RELATING TO of cases, as a means of adaptation to changed conditions, especially to a drier climate. From this] are derived the unifoliolate forms through the disappearance of the lateral leaflets, the imparipinnate by multiplication of the lateral leaflets. Special attention is paid to the structure of the leaves in Mimoseae, and especially in the genus Acacia , with its very large number of species in which the leaves are replaced by phyllodes. All the phyllodineous species of Acacieae are heterophyllous ; but the heteropliylly is usually limited to the youngest stages of the seedlings, and the appearance of pinnate leaves must be regarded as a phenomenon of reversion. The reduction of the leaves is commonly accompanied by the appearance of wings on the stem, which may be metamorphosed lower leaflets or meta- morphosed stipules. They serve, like the leaves, as organs of assimila- tion. Spotted Leaves.* * * § — Prof. G. Arcangeli refers to a number of other instances (in addition to Arum italicum) of plants with spotted leaves, and suggests that the variegation may serve different purposes in differ- ent cases, viz. : — in promoting the functions of transpiration and respi- ration ; in protecting the assimilating tissue from too intense radiation ; in defending the parts affected from the injurious effects of cold ; in promoting the visits of pollinating insects ; in contributing to the beauty and elegance of the leaf, and thus promoting the dissemination and dif- fusion of the species. Hydathodes of Tropical Plants. — Herr S. H. Koorders + describes the adaptation of the calyx for the exudation of water in 13 tropical species, of which 6 belong to the Bignoniaceae, 3 to the Solanaceae, 2 to the Verbenaceae, and one each to the Scrophulariaceae and the Zingiberaceae. The exudation always takes place on the inner surface of the calyx, sometimes also on the outer surface of the corolla. The hydathodes are multicellular capitate hairs, the surface of which is covered by a cuticle through which the exudation takes place. The water remains in the calyx throughout the development of the flower, and in one case till the fruit is formed ; during this period the floral organs are covered with a coat of mucilage like the young organs of aquatic plants. On the inner side of the calyx the stomates are very few or entirely wanting. Bacteria or fungus hyphae were invariably found within the water-calyx, but never more than one kind in the same species. There is the closest con- nection between hydathodes and nectaries, these organs differing only in the nature of their secretion. The same trichome may perform different functions at different periods. Herr H. Hallier j calls attention to another example of a water-calyx in Leea amabilis, belonging to the Ampelideae. Adhesive Discs of Ercilla.§ — Mr. J. H. Burrage describes the adhe- sive discs borne immediately above the axils of the leaves in Ercilla volubilis, belonging to the Phytolaccaceee. They have several points in common with those of the Virginian creeper, attaching themselves to a * Bull. Soc. Bot. Ital., 1897, pp. 198-203. Cf. this Journal, ante , p. 217. t Ann. Jard. Bot. Buitenzorg, xiv. (1897) pp. 354-4:77 ( 7 pis.), t Tom. cit., pp. 241-7. § Journ. Linn. Soc. (Bot.), xxxiii. (1897) pp. 95-102 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 551 support by means of a mucilaginous secretion, which exudes only at early contact from the apices of hairs which cover the whole surface of the disc. Their sole function appears to be to assist the plant in climbing. The discs are developed endogenously immediately above the axils of the leaves. Each is made up of a parenchyme with a central plate of tracheids, in connection with the bundles of the stem at the base of the disc. When growing in a moist atmosphere the discs will sometimes put out roots. Structure of Halophytes.* * * § — Prof. E. Warming describes the struc- tural peculiarities of salt-loving plants from various climates, comparing them with xerophytes, between which two classes there is no well- marked division-line. Reference is made to 90 species, which are arranged under 16 classes. The leaves are usually fleshy and succulent, with thick cuticle and depressed stomates. Spongy parenchyme is rare. The mechanical tissue is, as a rule, feeble, and the plant is but seldom covered with hairs. Morphology of Viola. — Herr H. Kramer f has undertaken a careful examination of the structure of the various organs of Viola , especially of V. tricolor and its allies. Among the more interesting of the results are the following : — Many of the epidermal cells, e.g. those which lie between the guard-cells of the stomates, are divided by a tangential wall into two cells, the outer one of which remains as an epidermal cell, while the inner one is connected into a mucilage-cell. The wall of the mucilage- cell consists of pure cellulose, and is very frequently provided with simple dots. These mucilage-cells appear to occur in all species of Viola , and in all the foliar organs except the stamens. Prof. V. B. Wittrock t records the results of a similar examination of the species belonging to the section Melanium of Viola. The flowers differ remarkably, both in size and marking, at different periods of the year ; the pollen-grains are also dimorphic or trimorphic. V. tricolor is (in Sweden) as a rule cross-pollinated by Lepidoptera and Hymenoptera ; while the nearly related V. arvensis is usually self-pollinated ; and there are corresponding differences in the two species in the arrangement and markings of the parts of the flower. The author enters into further details respecting the vegetative organs of the species of Viola in question, and then discusses their phy- logenetic relationships, and the origin of the various cultivated forms. Contractile Roots.§ — Herr A. Rimpach sums up the facts known with regard to contractile roots, which he finds in 70 species belonging to 20 orders of Monocotyledons and Dicotyledons. They have been observed only in herbaceous, and especially in geophilous plants. The greatest amount of contraction was to the extent of 70 per cent. In Monocotyledons it is only the inner parenchyme of the cortex that takes * D. K. Dansk. Vidensk., viii. (1897) pp. 173-272. See Bot. Centralbl., lxxi. (1897) p. 455. f ‘ Viola tricolor L., in morph., anatom., u. biol. Beziehung,’ Marburg, 1897, 67 pp. and 5 pis. See Bot. Ztg., Iv. (1897) 2te Abth., p. 177. X Acta Horti Bergiani, ii. (1896, 97) Nos. 1 and 7, 78 and 142 pp., 15 pis. and 87 figs. See Bot. Centralbl., lxxi. (1897) pp. 133, 140. § Beitr. z. wiss. Bot. (Fiinfstuck), ii. (1897) pp. 1-28 (2 pis.). Cf. this Journal, ante, p. 307. 1897 2 q 552 SUMMARY OF CURRENT RESEARCHES RELATING TO an active part in the contraction ; in many Dicotyledons the parenchyme within the vascular system appears also to have its share in the process. The power of contraction may he confined to roots of a particular order, or to those produced at one time only of the year. They may be found in some species of a genus and not in other closely allied species. The orders in which they have at present been found most frequently are the Liliaceae, Irideae, Amaryllideae, and Araceae. Root of Suaeda and Salsola.* — M. G. Fron reports the results of an examination of the structure and development of the roots of species of these genera of Chenopodiaceae, anomalous from the develop- ment at a more or less early period of a generative fibro vascular layer in the pericycle. He states that the root, when young, presents an asymmetry of structure, which is exhibited from the earliest formations, and is developed further in the secondary formations, especially in those which are anomalous. (Edema in Roots of Salix.f — In the roots of Salix nigra , growing in water, Mr. H. v. Schrenk finds, in the winter, peculiar structures pre- senting a superficial resemblance to lenticels, but differing from them in structure and function. They consist of a collection of cells elongated radially, and in some cases bursting the epiderm. They appear to be formed from a very strong absorption of water in consequence of an ab- normally high temperature, which was unable to escape in the ordinary way from the absence of transpiring leaves. j3. Physiology. (1) Reproduction and Embryology. Embryogeny and Fertilisation in Lilium.J — Prof.1 J. M. Coulter, Mr. C. J. Chamberlain, and Mr. J. H. Schaffner have followed out the development of the sexual cells and the process of impregnation in several species of Lilium , especially L. pliiladelpliicum. The following are some of the more important points noted : — In the development of the embryo-sac, a single large hypodermal archesporial cell makes its appearance very early, and there is no evidence of the cutting off of a tapetal cell. The sequence of cell-divisions usual in Angiosperms is entirely suppressed, and the archesporial cell develops directly into the macrospore or embryo-sac. The persistence of the spindle-fibres is a common phenomenon in the embryo-sac divisions, and often helps to indicate the shifting of the freed nuclei. When the pollen-tube has reached and passed the synergids, it comes under the con- trol of an influence powerful enough to bend it sharply towards the oosphere. The first division of the oosperm is always transverse, re- sulting in a small apical cell and a comparatively large and somewhat vesicular basal cell. The tissue of the suspensor is erythrophilous as compared with the embryo, showing its close relation to nutritive sup- plies. In the development of the endosperm, the sexual and polar pairs of nuclei were observed to fuse simultaneously ; but when division begins the endosperm nuclei divide more rapidly than the cells of the embryo. In their early spirem-stages the nuclei of the mother-cells of the * Comptes Rendus, cxxv. (1897) pp. 366-8. f Bot. Gazette, xxiv. (1897) pp. 52-4 (2 figs.), i Op. cit., xxiii. (1897) pp. 412-52 (8 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 553 pollen-grains ( L . tigrinum) show a single much-twisted ribbon with a row of chromatin granules on each edge. In many cases the chromatin granules appear to be arranged in opposite pairs. Centrospheres were observed in connection with both the pollen-tube nuclei and the genera- tive nucleus. In many cases the pollen-tube nuclei were seen to divide. In L. philadelpJiicum the nucleus of the archesporial cell appears during the first division with 12 chromosomes. At an early stage the linin-thread of the chromatin-network begins to thicken, and the granules undergo transverse fission. After division of the granules the whole chromatin band undergoes longitudinal splitting, and the double threads thus produced begin to twist upon each other. The twisted band finally manifests itself as a single continuous spirem, which doubles up and twists into twelve loops. These break apart and give rise to the twelve chromosomes. The two linin-threads with their granules, which com- pose the loop, continually become more intimately associated, so that the loop appears like a single linin-thread with two irregular rows of chromatin-granules. The chromatin-loops become shorter by contrac- tion, and receive a thick deposit of some substance which stains light at first, but later takes the same colour as the chromatin. The chromo- somes arrange themselves in the equatorial plane in such a manner that the end containing the two free ends of the original chromatin-loop is untwisted and finally cut in two by a transverse division. The nucleus has at first about three nucleoles, each with one or more large granular vacuoles. After the longitudinal splitting of the chro- matin-band, there arise in the nuclei numerous small vacuolated bodies. These are successively abstricted from the mother-nucleole by a process of budding, and give rise to numerous micronucleoles, which all pass out into the cytoplasm before the formation of the mother-star ; and later, at about the beginning of the close daughter-skeins, these micro- nucleoles all pass back into the daughter-nuclei, and by aggregation form the new nucleoles of the daughter-nuclei. This process is re- peated for every division of the female gametophyte. At about the time of the division of the chromatin-granules, there appear in the cytoplasm peculiar cytoplasmic threads which pass from one side of the cell to the other, and are mostly tangent to the nucleus. At a later stage, at about the beginning of the nuclear migration, these threads have disappeared, and numerous radiating threads pass out at right angles from the nuclear surface and extend to the cell-walls. Similar radiations appear round the daughter-nuclei; and the micro- nucleoles, as they are drawn into the daughter-nuclei, seem to be in contact with these cytoplasmic threads. Two centrospheres appear beside the resting nucleus, and, in the mother-star stage, a single centrosphere appears at each pole of the spindle ; while a little later, during metakinesis, a centrosphere appears at each point with a double centrosome. In the daughter-skein stage there are two centrospheres at each pole, which are often quite distinct, and can easily be differentiated from the micronucleoles. Fertilisation and Embryogeny of Triticum.*— Herr M. Koernicke has made a detailed examination of the processes which take place before * Yerhandl. Naturhist. Ver. Preussen Kheinl., liii. (1896) pp. 149-85 (1 pi. and 3 figs.). v 2 Q 2 554 SUMMARY OF CURRENT RESEARCHES RELATING TO and after impregnation in the embryo-sac of a variety of the cultivated wheat. The following are the more important results. The mother-cell of the embryo-sac divides into four superposed daughter-cells, separated from one another by strongly swollen septa. The terminal one of these four cells develops into the embryo-sac, while the remaining three become gradually disorganised. It is rare to find in the embryo-sac of Triticum only three antipodals ; usually one of the three divides into a very large number, apparently by direct division. While the secondary nucleus of the embryo-sac is being formed, the membranes of the synergids and of the ovum-cell become somewhat thicker ; the former differ from the latter in their more elongated form. In the divisions which take place in the pollen-mother-cells, it appears certain that the greater part of the spindle-fibres are derived from the surrounding protoplasm. In the vegetative portion of the inflorescence the number of chromo- somes in a nucleus is usually 16, though as many as 24 have been observed. In the nucleus of the mother-cell of the embryo-sac and in the pollen-mother-cells there are only 8. In the fertilised ovum-cell the normal number of 16 is again attained. The object of the remarkable increase in the number of antipodals appears to be to supply nutrient material to the endosperm rather than to the fertilised ovum-cell. Antherozoids of Zamia.* — Mr. H. J. Webber announces the discovery of motile antherozoids in Zamia integrifolia , and describes a peculiar structure of the pollen-tube. After the pollen-grain has germinated, there are found in the pollen- tube, near its basal end, two cells, one in front of the other. The pos- terior of these cells is spherical or slightly elongated. The nucleus of the original cell has divided into two, one of the daughter-nuclei forming within the parietal utricle a new and wholly distinct utricle which delimits a cell lying entirely within the mother-cell, and surrounded on all sides by a layer of protoplasm of nearly uniform thickness. The anterior is much larger than the posterior cell, and is provided with two small spherical organs, situated at the opposite ends of the nucleus, outside the nuclear wall, and somewhat resembling centrosomes. Each of the daughter-cells formed by the division of the generative cell develops into a motile antherozoid, two being thus formed in each pollen-tube. They are encircled by a spirally arranged band of cilia developed from the centrosome-like body. The membrane formed by the wall of this body in its disintegration forms a band lying free in the cytoplasm of the cell. It becomes greatly extended in length, and forms a spiral band or ribbon with five or six coils. On the outer side of this band are very numerous protuberances which develop into the motile cilia of the mature antherozoid. The mature antherozoids pass into the arche- gone through a rupture in the end of the pollen-tube, the watery 'contents of the tube supplying a drop of water in which they can swim. They are of very large size, visible to the naked eye, 258-332 /x by 258-306 /x. There is no free tail. The nucleus is very large, and is surrounded on all sides by a thin layer of cytoplasm. The motion of the antherozoids * Bot. Gazette, :xxiii. (1897) pp. 453-9; xxiv. (1897) pp. 15-22 (1 pi. and 5 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 555 is a rotating one, tlie cilia continuing to vibrate for a considerable period after the rotation has ceased. Development of Pollen-Grains of Allium.* — M. C. Ishikawa has studied the development of the pollen-grains in Allium Jistulosum. On the first division of the pollen-mother-cells each of the eight chromosomes splits longitudinally, and many of the chromosomes thus formed become bent into a Y-shape. These gradually shorten, and unite into groups of four at the joints. When such a group of chromosomes assumes an equatorial position, the separate chromosomes of each pair are so arranged in the equatorial plate that one faces each pole. After nuclear division we have at each pole of the karyokinetic spindle eight Y-shaped daughter- chromosomes. Each of these daughter-chromosomes is now broken through at the point where the two arms meet, the mode of division being transverse, not longitudinal. In the first division, therefore, each pollen- mother-cell undergoes in succession a longitudinal and a transverse division, so that we get finally eight pairs of chromosomes or 16 separate chromosomes at each pole. Then each chromosome of the daughter- nuclei breaks up into microsome grains. The second division, which finally produces four pollen-cells, proceeds heterotypically. The chromosomes take the form of rings, and are eight in number. No longitudinal division takes place ; the nucleus of each pollen-cell contains eight simple chromosomes. The formation of the vegetative and generative nuclei in the pollen-cell is usually completed by each chromosome undergoing longitudinal division. Development of Sexual Cells in Typha.j — Mr. J. H. Schaffner has followed the development of the stamens and carpels in Typha latifolia. Notwithstanding the primitive type of flower, it presents a highly modified archesporial region. There is only a single archesporial cell, from which a single primary tapetal cell is cut off, this again dividing into two cells by a vertical wall. Polyembryony in Allium odorum.t— Herr F. Hegelmaier is able to confirm, in all the main points, the account given by Tretjakow § , of the occurrence of several embryos in the embryo-sac of Allium odorum. The adventitious embryos are never the result of direct impregnation by a pollen-tube, and may be regarded as parthenogenetic, being apparently due to an excitation resulting from the impregnation of the ovum-cell. These adventitious embryos are of 3 kinds : — (1) Derived from the egg- apparatus, i.e. from the abnormal development of one or both of the synergids. (2) Derived from the antipodals. In only one case did two of the antipodals develop into embryos ; never more than two. The author was unable to detect any predisposition in one of the antipodals over the others. (3) Parietal adventitious embryos, springing from the inner surface of the ovule at different, apparently arbitrary, spots, but usually at some distance from the egg-apparatus. The author was not successful in tracing these adventitious embryos back to the unicellular condition. Two may occur in the same ovule, or one accompanied by one of either of the other kinds. * Journ. Coll. Sci. Tokyo, x. (1897) 31 pp. and 2 pis. See Bot. Centralbl., Ixxi. (1897) p. 211. t Bot. Gazette, xxiv. (1897) pp. 93-102 (3 pis.), i J Bot. Ztg., lv. (1897) pp. 133-10 (1 pi ). § Cf. this Journal, 1895, p. 450. 556 SUMMARY OF CURRENT RESEARCHES RELATING TO (2) Nutrition and Growth (including1 Germination, and Movements of Fluids). Influence of the Dark Heat-Rays on the Growth of Plants. * * * § — By growing plants beneath a concentrated solution of alum, Herr N. H. Nilsson has tested the effect on their growth of the dark heat-rays as compared with that of ordinary sunlight. Among the more important uniform results are the following : — The epidermal cells are larger, and have more wavy walls, the outer and radial walls being thinner ; the quantity of hairs is reduced ; the palisade-cells are shorter radially ; and the intercellular spaces in the palisade-parenchyme are larger. Different species showed different results as respects the size of the leaves and of the stomates, and the absolute size of the spongy parenchyme. Germination of Parasitic Phanerogams.f — Herr E. Heinricher states, as the result of experiments on various species of Rliinanthege, that the germination of the seeds takes place independently of any chemical irritation from a host-plant ; but that the haustoria are produced only as the result of the chemical irritation exercised by a second living root. New Mode of Grafting.^ — M. L. Daniel advocates a new process of grafting which he terms the greffe en flute-apjproche, and which he claims to combine the advantages of the “ flute-method ” (greffe en flute') and the “ shield-method” (greffe en ecusson). It is described as being certain in its results, but it takes more time than the methods already in use, and is applicable rather to the perpetuation of special varieties than to use for ordinary purposes of cultivation. Role of Water in Growth.§— Mr. Co B. Davenport compares the developmental processes occurring at the tip of a twig and those in the animal embryo. In both there is first a period of rapid cell-division with slow growth ; next a grand period of growth in which the general form of the embryo is acquired, the rudiments of the organs are estab- lished, and the organism increases rapidly in size by the imbibition of water ; and lastly, a period in which histological differentiation is carried on, while the absolute growth increments cease to increase. Transpiration in the Tropics.|j — Erom series of observations made in Java and at Wageningen (Holland), Herr E. Giltay doubts the accuracy of Haberlandt’s statement % that transpiration is much less energetic in the Tropics than in the temperate climate of Central Europe. He does not, however, consider that any of the experiments as yet made are on a sufficiently extended scale to settle the question. Currents of Pigments and Saline Solutions in Dicotyledons.** — Herr E. Tschermak finds a remarkable difference between the paths taken by coloured solutions and by solutions of salts in the ascending current in dicotyledonous, woody, and herbaceous plants. The pigments employed were aqueous solutions of sodium-indigo sulphate, fuchsin, saffranin, * SB. Bot. Yerein Lund, Nov. 14, 1896. See Bot. Centralbl., lxxii. (1897) p. 21. f Ber. Naturw.-med. Ver. Innsbruck, xxii. (1896). See Bot. Centralbl., lxxi. (1897) p. 318. X Rev. Gen. de Bot. (Bonnier), ix. (1897) pp. 213-9 (12 figs.). § Proc. Boston Soc. Nat. Hist., xxviii. (1897) pp. 73-84. || Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 615-44. Cf. this Journal, 1893, p. 208. ** SB. K. Akad. Wiss. Wien, cv. (1896) pp. 41-70. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 557 gentian-violet, and eosin ; the saline solutions, lithium chloride, barium chloride, strontium nitrate, calcium nitrate, sodium chloride, and ferric chloride ; the first-named in each group giving the best results. In both herbaceous and woody dicotyledons the vascular bundles acted, in all the cases examined, as the sole conductors of soluble pigments, which never spread beyond them into the adjacent tissues. In woody species particular branches or parts of the plant appeared to be in connection, as far as the absorption of pigments is concerned, only with definite portions of the root. The saline solutions, on the other hand, after ascending through the vascular bundles, diffused themselves after a time through the adjacent tissues and finally through the whole plant. In the absorption of nutrient substances any particular part of the plant is not dependent on the activity of any special portion of the root, but rather on the entire accumulation of salts in the stem, which again is derived from the activity of the entire root. Excretion of Drops of Water from Leaves.* — Dr. A. Nestler states that, while the excretion of drops of water from the leaves of plants is often effected by special organs (hydathodes), this is not always the case. In Agapanthus umbellatus , which has neither epitheme nor water-pores, it takes place partly on the upper side of the leaf, partly on the under side of the apex. In grasses it may be brought about in various parts of the leaf. In Tradescantia viridis the exudation is effected through water-clefts placed in a row on the margin of the upper side, the only stomates on this side of the leaf. In Phaseolus multiflorus the club- shaped hairs do not appear to have this function. Aeration of the Stem of Mikania. j — Mr. W. W. Rowlee finds that the primary root of Mikania scandens gives rise to a great number of slender lateral roots, especially on the upper side, which grow towards the surface of the water of the marshes in which the plant flourishes. He regards these as aerotropic organs. When planted in dry soil, these roots appear as small erect knees, containing a large number of schizo- genous air-passages, which appear every year. (3) Irritability. Sleep of Plants.]; — Pursuing his investigation on the advantages afforded to plants by the nocturnal position of the leaf or leaflets, Herr E. Stahl finds, in a large number of plants examined, that it acts as a protection against the deposition of dew. The effect is to promote transpiration, and thus increase the amount of nutriment conveyed to the assimilating organs. He does not favour the view that the main object is a protection against excessive radiation. The nocturnal position of leaves or leaflets may be classed under two heads : — (1) They are directed downwards, so that the under side is better protected than the upper side against the deposition of dew (Bio- phylum sensitivum , Oxalis Acetosella , Bobinia pseudacacia , Hedysarum gyrans, Impatiens noli-tangere, &c.). (2) They are so placed that the * SB. K. Akad. Wiss. Wien, cv. (1896) pp. 521-50 (2 pis.). t Proc. Amer. Micr. Soc., xv. pp. 143-56 (6 pis ). See Bot. Centralbl., 1897, Beih.,p. 95. * X Bot. Ztg., lv. (1897) lte Abth., pp. 71-109. Cf. this Journal, 1895, p. 657. ^58 SUMMARY OF CURRENT RESEARCHES RELATING TO upper side is better protected than the under side against the deposition of dew ( Colutea arborescens , Trifolium repens , Impatiens glanduligera, &c.). This difference is usually correlated with a difference in the disposition of the stomates, as is well seen in the different species of Impatiens ; but there are exceptions to this rule. Geotropism no doubt plays some part in promoting the vertical nocturnal position. Hydathodes are very abundant in the Oxalideee and other nyctitropic families. It is probable that the spontaneous movements in the leaflets of Desmodium gyrans, Trifolium pratense , and other plants, which have no relation to nyctitropism, and the easily provoked trembling of the leaves of the aspen, have also an advantage to the plant in promoting transpiration. Sensitive Cushions of Mimosa.* — In the primary cushions of the leaves of Mimosa pudica , Prof. S. Schwendener finds that the stereome- sheath which surrounds the central vascular bundle is composed of true collenchyme. The “ swelling parenchyme ” has on its inner side a zone, consisting of only a few layers of cells, with large intercellular spaces which are always filled with air. The larger peripheral portion has only very small intercellular spaces. The sensitive (lower) half of the cushion has always much thinner cell-walls than the other portion. The secondary cushions of the pinnee have essentially the same ana- tomical structure as the primary cushions, but the central bundle has always a ribbon-like form, and is composed of a collenchyme plate with about five vascular bundles lying side by side. On the sensitive side of the tertiary cushions are a number of stomates, which are, however, not in any way connected with their irritability. The difference between the cylindrical central bundle of the primary cushion and the ribbon- shaped bundle of the secondary cushions is connected with a difference in the mode of curvature. The upper and lower halves of the cushiony react in opposite direc- tions towards changes in the light. The upper half loses, while the lower half gains, in expansive power with loss of light, and vice versa. The mathematical conditions of the changes in position are discussed in detail. (4) Chemical Changes (including Respiration and Fermentation). Mucilage Excreted by Seeds.j — According to M. H. Coupin nearly all seeds excrete mucilage by a process of osmose when placed in water for the purpose of swelling. In the case of peas and haricots, the loss of weight by this process may be as much as from two to three per cent. The mucilage is derived both from the nucellus and from the integument, and the excretion is promoted by a high temperature. Secretion by the Scutellum.J — From a series of experiments made on the scutellum of grasses (chiefly Zea Mays), Herr J. Griiss has come to the conclusion that when the endosperm has been removed during germination, the seeds have the power of converting starch into sugar, even without the agency of bacteria. * SB. K. Preuss. Akad. Wiss. Beilin, xiv. (1897) pp. 228-57 (1 pi.). t Rev. Gen. de Bot. (Bonnier), ix. (1897) pp. 241-4. j Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger^ xxx. (1897) pp. 645-64 (1 fig.). Cf. this Journal, 1895, p. 200. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 559 Function of Antitoxins.* — Dr. H. A. Cummins suggests tliat the principal purpose served by the formation of antitoxins (alkaloids and others) in plants is to protect them against the attacks of injurious bac- teria in the soil. This is confirmed by the fact that the production of poisonous principles varies in the same species with the nature of the soil. The antiseptic principles appear usually to be produced as the result of irritation of the cells by the entrance of organisms which cause fermentation of the juices of the plant, the antitoxin then killing the invading organism. Advances in the Chemistry of Fermentation.! — In an introduc- tory address, Prof. E. Buchner, after reviewing the history of the physio- logy of fermentation, alluded to Traube’s idea of the existence in yeast-cells of a body capable of exciting fermentation. The ill success of numerous experimenters in isolating this fermenting substance from the yeast-cells in the same way that invertin was isolated, resulted from the difficulty in crushing the thick cell-membrane in all the cells of a large quantity of yeast, and therefore of quickly emptying the cells of their contents. The author mixed the yeast with quartz sand. After long rubbing the mash becomes moist, and the fluid portion of the cell-contents escapes. Water is then added, and the whole mass exposed to a pressure of 500 atmospheres. From the press runs out an almost clear yellow fluid, which amounts to nearly half of the whole of the cell- contents. In six hours 500 cubic cm. of juice can be obtained from one kilogram of beer yeast. This juice possesses the property of fermenting carbohydrates without the presence of organisms. Mixed with one volume of strong saccharose solution, the development of C02 begins in a quarter of an hour, and in a refrigerator continues for more than 14 days. In this way alcohol is formed. Cane-, grape-, fruit-, and malt-sugars are fermentable just as well as with a living ferment, but not mannite or milk-sugar. The fer- ment, which is designated zymase, has the characters of albuminous bodies. It is not living protoplasm, as chloroform does not inhibit its action. Under natural circumstances it is apparently excreted by the yeast-cells, and becomes diffused in the fluid, and in this way effects the decompo- sition of sugar. Zymase is diffusible through parchment paper. By precipitation with alcohol it is rendered insoluble in water. When heated to 40°-50° there is a copious deposit of albumen, and the filtrate has no fermenting power. The ferment is so inconstant that after standing for five days in the refrigerator in half full flasks, its efficiency disappears. Hence the author thinks that zymase is more closely allied to the living protoplasm of the yeast-cells than to invertin, and belongs to the genuine or native proteids. Butylalcohol Fermentation.^ — Induced by Fitz’s works, Herr 0. Emmerling sought in cow-dung and in hay for the ferment which decom- poses glycerin in butylalcohol ic fermentation. After frequent failure he finally succeeded in obtaining this fermentation from hay grown in Alsace. The Butyl-bacillus thus found is identical with that described by Fitz, but not with the Granulobacter saccharobutyricus of Beyerinck. * Proc. Asiatic Soc. Bengal, 1897, pp. 15-21. f Tubingen, 1897, 23 pp. See Bot. Centralbl., lxxi. (1897) p. 38. Cf. this Journal, ante, p. 414. ‘ J Ber. Deutsch. Chem. Geselh, 1897, No. 4. See Centralbl. f. Bakt. u. Par., 2te Abt., iii. (1897) p. 322. 560 SUMMARY OF CURRENT RESEARCHES RELATING TO y. General. Mechanical Effect of Rain on Plants.* * * § — From observations made in Java, Herr J. Wiesner altogether disputes the injurious effects alleged to be produced on leaves and flowers even by tropical rain. He never observed any splitting or tearing of leaves or petals even by the heaviest rain, when not accompanied by strong wind. When flowers or leaves are bodily torn away by rain, it is because their tissues had already undergone the change which made them nearly ready to fall. The im- munity from the effects of heavy rain is due to the elasticity of the flower-stalk or leaf-stalk. If these organs are fixed so as to have no power of movement, the impact of a falling body of only one-thousandth the weight of a heavy drop of rain will have a destructive effect. A moderately heavy rain has no effect on the leaves of Mimosa pudica. Freezing of Plants.^ — From a series of observations made on tropical plants, Herr H. Moliscli states that the freezing of plants at a temperature above zero (C.), independently of their transpiration, is the result of chemical rather than of physical changes in the living substance ; some chemical processes, such as the formation of chlorophyll and of etiolin, respiration, and the assimilation of carbon dioxide, being largely dependent on the temperature, while other processes are not. B. CRYPTO GAMI A. Cryptogamia Vaseularia. Parthenogenesis in Marsilia.J — Mr. W. R. Shaw lias succeeded in cultivating embryos of Marsilia Drummondii from female protliallia in which the archegones were completely isolated from any possible access of anthcrozoids. About one-half of the megaspores thus sown ger- minated. The embryos were slightly smaller than those produced in the ordinary way. Regeneration of Selaginella.§ — Dr. J. Behrens describes the two modes of regeneration which occur in Selaginella, especially in S. in - sequalifolia, viz. by the independent growth of fragments of the stem, and by proliferation of the sporange. Muscineae. Hygroscopic Mechanism of the Peristome of Mosses.[| — Herr C. Steinbrinck compares the mechanism by which spores are thrown out of the sporange of a Moss with those which govern the bursting of a capsule or an anther in flowering plants. Like seeds, the spores of mosses are usually protected against rain by the outer teeth forming a dense cover- ing over the mouth of the sporange, due to the hygroscopic movements of its outer teeth. But in some cases the dissemination of the spores is promoted by rain. According to the behaviour of the peristome-teeth on drying, Mosses may conveniently be classified under three groups, * Ann. Jard. Bot. Buitenzorg, xv. (1897) pp. 277-353. t SB. K. Akad. Wiss. Wien, cv. (1896) pp. 82-95. i Bot. Gazette, xxiv. (1897) pp. 114-7. § Flora, lxxxiv. (1897) Erg'anzbd., pp. 159-66. || Tom. cit., pp. 131-58 (13 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 561 viz. : — (1) Those in which the outer teeth mostly or exclusively bend inwards ( Ceratodon , Barbula, Pylaisia ) ; (2) those in which they mostly or exclusively bend outwards ( Orthotrichum , Grimmia, Dicranum, Dicranella, Funaria , Fissidens ) ; (3) those in which the outer teeth have an oscil- lating movement on contracting and swelling (. Hypnum , Amblystegium , Plagiothecium , Bhyncliostegium , Brachythecium , Camptothecinm , Neckera , Homalia , Bryum , Mnium ). Examples of each of these groups are de- scribed in detail. The direction of the curvature of the teeth on an alteration in the moisture is determined, as in the sporange of a fern or in an anther-lobe, by the unequal solidity of their inner and outer surfaces. This property resides especially in their radial walls, which are capable of great swelling. Non-Sexual Propagation of Campylopus flexuosus.* — Hen* J. Familler has investigated the mode of propagation of this moss, by the separation of very slender small-leaved branches, which become detached at the slightest touch. These do not develop directly into a new moss- plant, but produce a protoneme on which the leafy plant arises in the ordinary way as a lateral outgrowth. The moss grows in swampy places, and is probably partially saprophytic. It rarely produces fructification. Biology and Physiology of Marchantiaceae-t — Herr Z. Kamerling has studied several points in the structure and development of the Mar- cliantiacese and allied families. The rhizoids with peculiar conical outgrowths on the inner side of the cell-wall (. Zapfclienrhizoiden ) are found in several species ( Mar - cliantia and Lunularia ). Rejecting the theories of previous observers as to the function of these rhizoids, the author believes at least one pur- pose of the projections to be to counteract the injurious effects of bubbles of vapour in hindering the circulation of water through the rhizoids. In accordance with this view, the development of this kind of rhizoid is largely correlated with the nature of the habitat of the species. The strongest development of the conical projections was seen in the stalk of the inflorescence of Preissia commutata. In Marchantia polymorplia they frequently have a spiral arrangement. The rhizoids spring from the under side of the thallus, and are protected by scales. The air-chambers of the Ricciese and Marchantieae are described. The stomates are of two kinds, according as the divisions in the mother- cell take place at right angles or parallel to the surface of the thallus, the canal-shaped stomates being the result of the latter process. The structure of the stomates differs in minor details in different genera. In reference to their habits and biology, the author classifies the Marchantiales under six types, viz. : — The ephemeral type ( Biccia glauca , Bicciocarpus natans, & c.) ; (2) the xerophytous type (Biccia lamellosa, Oxymitra py rami data, Targionia Tiypopliylla , &c.) ; (3) the alpine type ( Clevia , Sauteria, Peltolepis) ; (4) the Lunularia type ( Marchantia pal- mata , Lunularia cruciata, Fimbriaria stahliana, &c.) ; (5) the hygrophilous type ( Fegatella conica, &c.) ; (6) the bog type (Marchantia polymorpha alone). * Flora, Ixxxiv. (1897) Erganzsbd., pp. 174-5 (2 figs.)- f Tom. cit., pp. 1-68 (3 pis.). 562 SUMMARY OF CURRENT RESEARCHES RELATING TO Algae. Food-Material of Algae and Fungi.* * * § — Dr. T. Bokorny gives the results of a series of experiments on the limits of dilution of sub- stances which can be taken up by the lower plants. Among the more noteworthy are the following : — In a 1 : 100,000 solution of fuchsin, Mesocarpus and Spirogyra became strongly coloured, and soon died ; a solution of 1 : 1,000,000 produced no effect. In a 1 : 100,000 solution of potassium biniodide, starch-grains assumed a violet tint in 24 hours ; with a solution of 1 : 500,000, the starch-grains were not coloured, but the cells ( Spirogyra ) were killed. Caffein produces the aggregation- reaction in the protoplasm with a dilution of 1 : 10,000 ; ammonia pro- duces the same result with a dilution of 1 : 100,000. A proportion of 1 : 100,000 of a mixture of potassium phosphate, magnesium sulphate, and calcium nitrate in water is sufficient to afford a supply of the neces- sary mineral ingredients of the food of Algae. Arboreal Algse.l — Among a collection of Algae gathered on trees in Samoa, Herr W. Schmidle finds the following new species Phycopeltis microcystis, Hansgirgia polymorpha , and H. irregulare, all on leaves ; also the following : — Dendronema confervaceum g. et sp. n. Cellulae minim ae, 2-3 p latae, 6-12 p longae, cylindricae et utrinque rotundatae, aut raro longe ellipticae, vix se attingentes, et praecipue materia firma hyalina non v. vix visibili in filum breve conjunctae ; fila simplicia, aequicrassa, paucicellulata, foliis Muscorum Hepaticorum aut Scytonematibus basi affixa, patentia, plerumque appropinquata, raro singula ; contentus chlorophyllosus (ut videtur) axialis, membrana pro ratione firma ; pyrenoidibus et nucleolis adhuc ignotis ; multiplicatio zoogonidiis rima e cellula effugientibus (ut videtur). Epiphytic on Hepaticae. Fossil Algae. | — Herr A. Rothpletz classifies the Fucoideae (or probably rather the Phaeophyceae) of the Flysch under six genera, viz. Phycopsis (including Chondrites , Chondrides , and Gigartinites ), Granularia (including Halymenites, Caulerpa , and Miinsterici), Keckia , Squamularia , Gryllophyllites, and Taonurus. A new genus, Siphonothallus , is also described, belonging apparently to the Siphoneae. New Marine Algae.§— Herr P. Kuckuck gives a more detailed description of the newly discovered genus Milcrosyphar from Kiel and Heligoland, with two new species, M. Porphyrse and M. Polysiphonise , growing on the respective seaweeds from which they are named. Two new species of PhaBosporeae are also described, Ectocarpus lucifugus and Lepto- nema lucifugum, growing in dark hollows, as well as other new species of Phaeosporeae and Florideae, and a new genus of Chlorophyceae, Sporo - cladus , resembling a small Cladophora, and developing sporanges from the terminal cells of primary and secondary branches, containing from * Biol. Centralbl., xvii. (1897) pp. 417-23. + Hedwigia, xxxvi. (1897) pp. 277-87 (4 pis.). X Zeitschr. Deutsch. Geol. Gesell., 1896, pp. 854-914 (3 pis.). See Bot. Cen- tralbl., lxxi. (1897) p. 71. § Beitr. z. Kennt. d. Meersalgen, 42 pp. and 7 pis. ; also Bemerk. z. marinen Algen -vegetation v. Helgoland, ii., 28 pp. and 21 figs. See Bot. Centralbl., lxxi. (1897) pp. 96 and 311. Cf. this Journal, 1896, p. 91. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 563 six to ten swarmspores. The swarmspores of Codiolum Petrocelidis have four cilia. Antherozoids of Dictyota and Taonia.* * * § — Mr. J. LI. Williams has detected motility in the antherozoids or pollinoids of Dictyota and Taonia, hitherto supposed to be immotile. On escaping from the antherid, the antherozoids were seen to swarm, and to display as great activity as those of Fucus. The cilia were clearly displayed on staining ; but it is stated that there are striking differences between the phenomena and those of the Fucaceae. Arrested Condition of Zygnema.|— Herr W. Schmidle describes a peculiar condition of a Zygnema from Australia, in which the protoplasts of the cells have undergone contraction into a spherical form, giving a torulose appearance to the filament. It appears to mark a transition between Zygnema and Zygogonium, to which latter genus it should pro- bably be referred. Fungi. Influence of Nutrient Media on the Development of Fungi. — M. J. Ray J has grown examples of the lower Fungi, chiefly Sterigmatocystis alba, in a variety of nutrient media, and finds the one character which remains constant to be the size of the spores. Almost all other charac- ters which are relied on as specific are liable to vary, while those which are regarded as generic are for the most part constant. The size of the cells of the filaments which compose the thallus is especially variable. When cultivated in liquids in motion, the cells are liable to assume a spherical form, or the thallus itself becomes rounded. In nature the vegetative elements springing from spores of the same origin may vary greatly, according to the conditions of germination and development. Herr A. Schmidt § gives full details of the effects of various nutrient fluids of different degrees of concentration on the development of the conids, gemmae, and ascus-fructification of Sterigmatocystis nidulans. Herr W. Schostakowitsch || has investigated the changes produced in Mucor proliferus ^ by external conditions. It varies exceedingly according to the temperature and the nature of the nutrient fluid. It may vary in height between 0’5 mm. and 7 cm. Swellings may appear below the sporanges, as in Pilobolus. The wall of the sporange may lose its deli- quescent property. The spores are subject to extraordinary variation in size, viz. between 2 and 67 /x ; they may become curved or lobed, hour- glass-shaped or cylindrical, and may germinate within the sporange. As the result of experiments made on some of the lower Fungi, Aspergillus niger , Penicillium glaucum, and Botrytis cinerea, Mr. H. M. Richards ** finds that many nutrient substances, both organic and inor- * Journ. of Bot., xxxv. (1897) pp. 361-2. f Flora, lxxxiv. (1897) Erganzbd., pp. 167-70 (11 figs.). i Rev. Ge'n. de Bot. (Bonnier), ix. (1897) pp. 193-212, 245-59, 282-304 (6 pis. and 4 figs ); Comptes Rendus, cxx. (1897) pp. 193-4. § • Ueb. d. Bedingungen d. Conidien-, Gemmen-, u. Schlauehfrucht-Production bei Sterigmatocystis nidulans ,’ Halle, 1897 (1 pi.). See Bot. Centralbl. lxxi. (1897) p. 98. || Flora, lxxxiv. (1897) Erganzbd., pp. 88-96 (1 pi.). «|[ Cf. this Journal, ante , p. 149. ** Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 665-88. 564 SUMMARY OF CURRENT RESEARCHES RELATING TO ganic, have a distinct influence on their growth. An increased activity of growth of the mycele is, however, frequently accompanied by a retardation in the production of conids. The colour of the conids is sensibly affected by the chemical composition of the nutrient medium. Pleomorphism of Fungi. * — In reviewing the question of pleo- morphism, Dr. 0. Jolian-Olsen follows the lead of Brefeld, who laid down the proposition that parasitism is to be regarded as an adaptation phenomenon ; and the author’s view is that, as a rule, the primary form of a fungus lives on dead matter, is a saprophyte in fact, and that if there be a parasitic form, this cannot exist for ever as a parasite, but must return to the saprophytic condition in order to regain the power of invading living tissue. A large number of examples of the variations of fungi under natural and artificial conditions are referred to, and these certainly lend colour to the view that so little is known as yet about these fungi that it would be wise not to dogmatise too strongly. Hence it would be better to regard most bacteria as adaptation forms, and not as independent species, and, after Coppen Jones, speak of Tuber culomyces just as we do of Actinomyces. Classification of the Spores of Fungi. | — M. P. A. Dangeard suggests a classification of the spores of Fungi, from the point of view of their origin, different from any of those which now prevail. Conids (e.g. Penicillium crustaceum ) he defines as spores which are derived from the continued division of the single nucleus of a mother-cell. These conids may, however, be of two kinds : — (1) they are the result of the budding of the mother-cell (. Aspergillus , Trichoderma lignorum , and many Mucedineae, spermogones of Uredineae, Saccharomyces'), and this is the most common mode of production ; (2) they result from the division of the mother-cell ( Sphserotheca Castagnei). The conid is, in its origin and structure, a nonsexual spore in every sense of the term. In the Coremium-st&ge of Penicillium the spores are not produced from a mother-cell, but by the breaking up into cells of multinucleated fertile branches, as in Oidium lactis ; and for this kind he proposes the term oidia ; they are not necessarily the result of the division of a nucleus. Chlamydospores are encysted oidia. The Ascomycetes and the Basidiomycetes produce both conids and oidia. Uredospores and aecidiospores must be regarded as conids. Both conids and oidia may be compound. Conids are altogether analogous to the spores of the Muscineae and Filices ; while oidia have more analogy to bulbs, gemmae, and similar structures. New Genera of Fungi. — In a collection of Fungi from South America, Herr P. Hennings J finds a number of new species, and the following new genera : — Ditella (Uredineae). Sporae continuae, catenulatae, sine cellulis inter- stitialibus, pseudoperidio tectae ; sori subtremelloidei, subglobosi, basi immersi. D. verruciformis , on leaves of Sida macrodon. Hypocreodendron (Hypocreaceae). Stroma carnosum, truncatum, fruticiformite ramosum ; perithecia stromatis parte superiori disciformi tantum immersa, subglobosa ; asci baud conspicui ; basidia ramosa ; * Centralbl. Bakt. u. Par., 2te Abb, iii. (1897) pp. 273-84 (1 ph). t Le Botaniste (Dangeard), v. (1897) pp. 313-7. j Hedwigia, xxxvi. (1897) pp. 190-246 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 565 conidia bacillaria, kyalina, continua. H. sanguineiim, in crevices of a trunk. Phseophacidium (Pkacidiaceae). Mycelium intercellulare ; ascomata superficialia, submembranacea/pulvinato-applanata, irregulariter laciniato- debiscentia, atra ; asci clavati, 8-spori, parapbysati ; sporae oblongae, continue, fusco-atrae. P. Escallonise , on leaves of Escallonia rubra. Septorella (Sphaeropsideas). Peritbeciis superficialibus, carbonaceis, opacis, nigris ; sporulis anguste fusoideis, curvulis, guttulatis, byalinis ; basidiis caespitosis, brevibus. S. Salacise on leaves of Salacia. Allescheriella (Hypbomycetes). Hypbae repentes, septatao, ramosm, hyalinas, subflavescentes ; conidia apice ramulorum oriunda, singularia, continua, subglobosa, ovoidea v. oblonga, laete colorata. A. uredinoides , on corticolous mosses. Negeriella (Hypbomycetes). Stromata filiformia, rigida, lateraliter ramosa, e bypbis atrofuscis septatis ramosisque composita; conidia apicibus ramorum singularia, subfuscoidea, pluriseptata, colorata. N. cJiilensis, on dead bougbs of a Eugenia. Didymoclilamys (Ustilagineae). Massa sporarum (?) in floribus nidulans, sacculo membranaceo inclusa ; sporae (?) continue, membrana duplici tectae, coloratae. I). ustilaginoidea, in the inflorescence of a Rhynchospora. From Marasmius Herr A. Scherffel * * * § separates those species which have coloured, especially brown, spores, constituting them into a new genus with tbe name Phseomarasmius , g. n. Eungi inhabiting Excrement. | — Prof. E. C. Hansen describes tbe structure and biology of several species of Coprinus found on the dung of Mammalia, viz. C. stercorarius, niveus, and Bostrupianus sp. n. Tbe latter species and C. stercorarius form types for two different modes of develop- ment, tbe one with obligatory, tbe other with facultative, formation of sclerotes. Tbe fungus previously described by tbe author as Eurotium stercorarium be now constitutes as tbe type of a new genus under tbe name Anixiopsis stercorarius , distinguished from Anixia by tbe absence of parapbyees, and by tbe spores being united into a more or less spherical group. Enngi Parasitic on Lichens. — In further investigation of this sub- ject, Prof. W. Zopf J describes a fungus parasitic on Pertusaria sulphurella , a Pyrenomycete with groups of peritbeces, wbicb be describes as a new species, Bosellinia Groedensis. It has tbe property of forming gemmae. Tbe fungus described as Bhymbocarpus punctiformis , parasitic on BJiizo- carpon geographicum, is tbe type of a new genus belonging to tbe Artko- nieae. Another new genus is represented by Dicothecium stigma , parasitic on several lichens, but effecting no injury in tbe gonids. Many other examples of parasitism are described. Prof. E. Kernstock§ makes a number of additions to Zopf’s list of Fungi parasitic or epiphytic on Lichens. * Hedwigia, xxxvi. (1897) pp. 288-90 (3 figs.). t Bot. Ztg., lv. (1897) lte Abth., pp. 111-32 (1 pi.). X Nova Acta K. Leopold.-Carol. Deutsch. Akad. Naturf., lxx. (1897) pp. 97-190, (2 pis.). See Bot. Centralbl., lxxi. (1897) p. 280. Of. this Journal, ante, p. 228. § Oesterr. Bot. Zeitschr., xlvii. (1897) pp. 9-11. 566 SUMMARY OP CURRENT RESEARCHES RELATING TO Red Pigment in Mucor.* * * § — M. P. A. Dangeard records the occur- rence, in a culture of Mucor racemosus, of an abundant red pigment, in- soluble in water and in alcohol, resembling that of Micrococcus prodigio- sus. The pigment is in oleaginous globules, or dispersed throughout the filaments. Syncephalastrum and Syncephalis.t — Mr. R. Thaxter discusses the relationship of these two little-known genera of Mucorini, and advo- cates the retention of the former as a distinct genus. The zygosperms of Syncephalis nodosa are described in detail. Diagnoses are given of the following new species : — Syncephalis Wynnese, on Wynnea macrotis ; S. pycnosperma, on dung of mice and sheep ; S. tenuis , on Sphagnum. Systematic Position of Protomyces.^ — From a study of the de- velopment of Protomyces macrosporus, parasitic on various Umbelliferae, M. Sappin-Trouflfy rejects all the hypotheses that have) at present been proposed with regard to its systematic position, viz. among the Usti- lagineee, among the Uredineae, and among the Exoascaceae. The spores do not contain two nuclei which subsequently conjugate, like those of Entyloma and of the asci of Exoascus ; the nuclei of the spores have a totally different origin, viz. from the thallus, and display no phenomenon of conjugation. He regards the genus as more nearly allied to the Chy- tridineae, and especially to Cladochytrium, where propagation takes place by cysts and by sporanges. Sexual Reproduction in the Ascomycetes.§ — From a fresh exami- nation of the mode of formation of the ascus in Spliserotheca Castagnei, M. P. A. Dangeard confirms his previous view of the inaccuracy of Harper’s statement || that there is an actual passage of a male reproduc- tive nucleus from the antherid into the archegone through an opening in the wall of the latter, and a fusion with its nucleus. He finds, on the contrary, that the cell which becomes segmented off at the apex of the antheridial branch exhibits degeneration of its protoplasmic contents from the moment of its segmentation. Nor was he able in any case to detect an orifice in the wall of the ascogone. The ascogone has at first only a single nucleus, which subsequently divides into two daughter- nuclei of equal size. Usually each of these again divides, and two septa appear, dividing the ascogone into a middle binucleated and two uni- nucleated cells, one at each end. The ascus is always derived from the binucleated cell after fusion of the two nuclei. Parasitic Fungi. — Under the name Bhizopus necans sp. n., Mr. G. Massee IT describes a parasitic fungus very destructive to the bulbs of lilies in Japan, but attacking them only when already injured. Mr. J. B. S. Norton** describes 33 species of Ustilagineae from Kansas, together with the results of experiments on the germination of the spores on different host-plants. There are two new species. * Le Botaniste (Dangeard), v. (1897) pp. 318-9. t Bot. Gazette, xxiv. (1897) pp. 1-15 (2 pis.). i Le Botaniste (Dangeard), v. (1897) pp. 285-8 (1 fig.). § Tom. cit., pp. 245-81 (17 figs.). Of. this Journal, 1894, p. 719. || Of. this Journal, 189G, p. 339. \\ Bull. Misc. Inform. R. G. Kew, 1897, pp. 87-90 (1 pi.). ** Trans. Acad. Sci. St. Louis, vii. pp. 229-41 (5 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 567 (Jredo Goebeliana * is a new parasitic fungus found by Herr F. Magnus on tbe leaves of a species of Parietciria in Venezuela, the first known to attack that genus. The “ soft spot” of the rind of oranges is, according to Mr. R. E. Smith,j due to the attacks of a fungus apparently identical with Peni- cillium digitatum , rather than with P. glaucum. Two little known parasitic fungi are described by Herr E. Rosen t ' Graphiola Phoenicis , on Phoenix deidylifera, a fungus of very uncertain affinities, possibly allied to the Ustilagineae, but differing in having a closed double peridium and a spore-distributing column ; and Botrytis longihranchiata, on Bleclmum hrasiliense and succulent flowering plants ; chiefly saprophytic, but facultatively parasitic. Fungus Parasitic on Pellia.§ — Mr. W. G. P. Ellis finds a fungus parasitic on the thallus of Pellia epiphylla , which proved to be the conidial form of an Ascomycete apparently identical with the Triclio- derma-phase of Hypocrea. It may be regarded as a saprophytic fungus taking on a parasitic phase. Development of Volutella.|| — On a rotten livacinth-bulb M. E. Boulanger finds a very polymorphic species of Volutella to which he gives the name V. scopula sp. n. Under cultivation in different media it assumes three different fertile forms, viz. : — a simple filamentous form ; a normal tubercular form or “ sporodochium ” ; and a filamentous form adapted to liquid media and bearing chlamydospores. Meliola.^F — On the ground of its basal asci collected into tufts, and of the presence of an ostiole, Herr F. Bucholtz separates Meliola from the Plectascinese, where it was placed by Fischer, and relegates it to the true Pyrenomycetes, where it must probably be accompanied also by Testudina , Zulcalia , and Ceratocarpia, Exobasidium Vitis.** — D. V. Peglion describes the structure and development of this parasite of the grape, preferring this nomenclature, rather than Aureohasidium Vitis. It differs from the other genera placed by Brefeld in the Hypochnacem in the spores giving birth, on germinat- ing, to numerous buddings, instead of developing directly into a myce- lial tube. Morphology and Biology of Lichens.jf — Pursuing the subject of the dependence of Lichens upon light, Herr H. Zukal points out that an exceedingly thin layer of chlorophyllaceous tissue will use up almost completely all the rays of light that promoto assimilation. The cortex of a lichen will absorb, on the average, about ten times as much light as the epiderm of higher organisms. The very large superficial develop- ment of Lichens in comparison to other Ascomycetes is due to the * Flora, lxxxiv. (1897) Erganzbd., pp. 17G-7 (2 figs.). + Bot. Gazette, xxiv. (1897) pp. 103-4 (1 pi.). X JB. Schles. Gesell. Vaterl. Cult., 1896 (1897). Zool.-bot. Sect., pp. 37-8. § Journ. Linn. Soc. (Bot.), xxxiii. (1897) pp. 102-17 (2 pis.). || Eev. Gen. de Bot. (Bonnier), ix. (1897) pp. 220-5 (1 pi.). 1 Bull. Herb. Boissier, v. (1897) (1 pi.). See Bot. Centralbl., lxxi. (1897) p. 271. ** Atti R. Accad. Lincei, vi. (1897) pp. 35-9. tt SB. K. Akad. Wiss. Wien, cv. (1896) pp. 196-264. Cf. this Journal, 1896, p. 658. 1897 2 r 568 SUMMARY OF CURRENT RESEARCHES RELATING TO enclosed Algae (gonids). With regard to the pigments of lichens, the author is unable to say whether they act in the same way as phycoery- thrin in the Elorideas, in promoting assimilation. Each species is adapted for a special intensity of light and combination of the coloured rays. The simplest form of ascus, such as that which occurs in Endomyces, is morphologically equivalent to the lateral chlamydospores ; both are apical swellings of a lateral branch. In the asci the ascospores are formed by endogenous cell-division ; while in other cases the mycelial cells are transformed in toto into chlamydospores or oidia. The author discusses further the various modes of propagation of Lichens ; the influence on their development of climate and substratum ; and the diseases to which they are subject. Lengthening of the Receptacle of the Phalloideae.* — According to experiments made by Mr. E. A. Burt on Dictyophora duplicata , the very rapid elongation of the receptacle after the “ egg,” or half-developed stage of growth, is largely dependent on an abundant supply of water. During the elongation, and coincident with the disappearance of the abundant store of glycogen present in the receptacle, there is a very rapid and general growth in size of the pseudo-parenchymatous cells which constitute its walls. The bursting forth of the receptacle from the volva and the straightening of its folded walls are due to this process of growth of the pseudo-parenchyme, during which the cells at the angles of the folds grow somewhat more spherical, and so become to some extent presumably active agents in the process of elongation. Blastomyeetes in Hypertrophied Tonsils.j* — Dr. A. de Simoni exa- mined twelve cases of hypertrophy of the tonsillar glands, and in all of them bodies which were recognised as Blastomyeetes %were observed. In the fresh condition the bodies are described as round, homogeneous, highly refracting, and of variable size. When stained they were found to be free and also endocellular, and not unfrequently budding. The stains used were lithium carmine and Gram’s method. Mostly the bodies were violet when stained, but some were surrounded by a rose- coloured halo. The bodies described are stated to be identical with the Blastomyeetes isolated by Sanfelice. Protopbyta. a. Schizopliycese. Pelagic Flora of the Swiss Lakes.f — Prof. R. Chodat gives some results of a comparison of the pelagic or plankton flora of the Swiss lakes, wdiick varies with the elevation, the composition of the water, and other conditions. The flora of the Jurassic lakes presents many features in common, independently of their altitude. Among these is the great abundance, in most of them, of Wiizolenia (sic) longiseta, and in some of them of Stephanodiscus Astrsea , and the great rarity of desmids. Oocystis IcicMsiris is one of the most abundant organisms. Of the floating Cyano- phyceee (flos aquae) Anabsena flos-aquee is the most widely distributed. Oscillatoria rubescens was only rarely met with. Many of the lakes pre- * Bot. Gazette, xxiv. (1897) pp. 73-92. f Centialbl. Bakt. u. Par., lte Abt., xxii. (1897) pp. 120-2. t Arch. Sci. Phys. et Nat, iv. (1897) pp. 166-73. ZOOLOGY AND BOTANY* MICROSCOPY* ETC. 569 sented characteristic features in the species of the plankton-flora peculiar to themselves. Movements of Diatoms.* — Mr. W. M. Kozlowski reviews the various theories which have been proposed to account for the movements of dia- toms, and sums up in favour of the efficient cause being assimilation. The chief ground of this conclusion is the dependence of the movements on the intensity, the colour, and the direction of the light. The author doubts whether the periodicity of tbe movements occurs in nature ; it may be the result of the artificial disposition of the light in the Microscope. Galiionella.f— Prof. W. Migula has had the opportunity of examin- ing the structure and development of the rare organism Gallionella ferru- ginea, found occasionally in water containing iron. He rejects the conclusions previously drawn as to its systematic position, whether among the Diatomaceae or the Confervaceae, and assigns it a place in the Cyanophyceae, between Leptotlirix and Spirulina. It has two dis- tinct forms. In one the threads are extremely fine, simple, yellowish, unsegmented, and irregularly coiled, about 1 p in diameter ; the other form has threads of about twice the thickness, which are distinctly segmented. These latter are seen, under a high magnification, to be ar- ranged in a double coil. The author does not believe in any genetic connection with Leptothrix ochracea. Re sting- Spores in a Calothrix.J — In a new species of Calothrix from the Sandwich Islands, C. sandwicense sp. n., Herr W. Schmidle finds resting-spores, resembling those described by Gomont in C. stagnalis. They occur in the cell immediately behind the basal heterocyst, one only in each cell. £. ScMzomycetes. Myxobacteriacea8.§ — Mr. R. Thaxter dissents from Zukal’s view |j that the Myxobacteriacece (Myxobotrysaceae) are Mycetozoa, and also throws doubt on several points in that writer’s account of the develop- ment of the organisms observed by him. Thaxter adheres to his former view that the Myxobacteriacese are Schizomycetes. Further details are given with regard to the germination of the spores and other points in the life-history of the group, and the following new species are described : — Chondromyces cipiculatus, on antelope-dung ; G. gracilipes, on rabbit- dung ; Myxococcus stipitatus, on dung of sheep, pig, &c. ; M. cirrltosus, on grouse-dung ; M. cruentus , on cow-dung. The author’s genus Myxo- bacter is sunk in Schroeter’s earlier Cystobacter. Evolution of Oxygen from Coloured Bacteria.^ — The experiments made by Dr. A. J. Ewart show that “ a number of coloured bacteria possess the power, under appropriate conditions, of evolving oxygen in greater or less amount. In certain of these the oxygen evolved appears to be occluded oxygen absorbed from the air by the pigment-substance * Bot. Gazette, xxiv. (1897) pp. 39-46. t Ber. Deutscli. Bot. Gesell., xv. (1897) pp. 321-7 (1 ph). + Flora, lxxxiv. (1897) Erganzbd., pp. 170-3 (3 figs.). § Bot. Gazette, xxiii. (1897) pp. 395-411 (2 pis.). Cf. this Journal, 1893, p. 370. |] Cf. this Journal, ante, p. 154. t Journ. Linn. Soc. (Bot.), xxxiii. (1897) pp. 123-55. 2 R 2 570 SUMMARY OF CURRENT RESEARCHES RELATING TO excreted by the bacteria. The process is not a vital one. Tbe substances contained in an alcoholic extract appear to have, though to a less extent, the same power of occluding oxygen, though this property is soon lost. The purple and green bacteria, in which the pigment forms an integral part of the bacterial plasma, show, when exposed to radiant energy, a very weak evolution of oxygen, continuing for an indefinite length of time if conditions are favourable. In the former of these the assimilat- ing pigment is bacterio-purpurin, in the latter chlorophyll. The pro- cess is a vital one, and the oxygen evolved is apparently derived from the assimilation of carbon dioxide.” Ferrophilous Bacteria.* — Herr G.Marpmann describes an iron bac- terium, which was isolated on silk-jelly. The rodlets, which are motion- less and devoid of cilia, are from 2-3 /x long and 0 • 8-1 /x broad. The ends are rounded, and there are polar black chromatophores with intervening grey granules. Many of the cells are black throughout. The pigment, which is insoluble in alcohol, ether, bisulphide of carbon, and benzin, contains both sulphur and iron. When cultivated on pepton-gelatin, the colonies were colourless, and did not give the iron reaction. Hence the iron must have been selected from the medium and assimilated by the bacteria. Root-Tubercle and other Bacteria in their Relation to Vegetable Tissue.j" — The chief results of the experiments made by Herr 0. Zinsser to determine more closely the relation of root-tubercle and other bacteria to living vegetable tissue, were that there is no hereditary infection of the seeds of Leguminosee ; for when cultivated under sterile conditions Leguminosae are devoid of root-tubercle. The bacteria are not to be met with in the internal parts of the rootlets, nor in the portions of the plant above the earth ; and even when artificially introduced they seem neither to wander very far from the inoculation site, nor to live very long. Other kinds of bacteria seem to behave in very much the same way towards healthy plants. The root-tubercle bacilli do not appear able to form nitrogenous compounds necessary for their existence, by assimilation of free nitrogen. Besides the mere presence of rhizobes, certain associated conditions are necessary for the development of root- tubercles. Sensitiveness of Frogs to Infection with Plague. J — Herr D. V. Devell states that frogs ( Hana temporaria) are sensitive to the virus of plague, both in summer and in winter. They may be infected by the introduction of cultures, or bits of organs of animals affected with plague, into the lymph-sac. Spontaneous infection of frogs may occur if the skin be wounded. From infection with bacilli of constant viru- lence for white mice (death in 2-2^ days), frogs die of plague in from 13-19 days. After one passage through the frog, the plague bacilli kill frogs in 12-14 days, after a second passage in 7-8 days, and after a third in 5 days. Antivenomous and Antitoxic Qualities of the Bile of Serpents and of other Animals.§ — Prof. Fraser has shown that the bile of certain * Centralbl. Bakt. u. Par., lte Abt., xxii. (1897) pp. 124-7. + Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 423-52. X Centralbl. Bakt. u. Par., lte Abt., xxii. (1897) pp. 382-5. § Brit. Med. Journ., 1897, ii. p. 595. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 571 animals possesses tlie property of rendering venoms and toxins inert. The experiments were made with diphtheria toxin and rabbit’s bile, and with cobra venom and ox gall. Rise and Fall of Bacteria in Cheddar Cheese.* — Mr. H. L. Russell and Mr. J. Weinzirl thus summarise the results of their analytical study of the bacterial changes that take place in the curing of American Cheddar cheese. There is at first .a marked falling off in the number of bacteria in the green cheese for a day or so ; this is followed by a rapid increase, the number of bacteria being scores of millions per gram. After this the numbers sink until they become insignificant. The maximum development is hastened or retarded by external conditions, such as temperature, moisture, square across. The other parts are — 8, a steel spring clip, and h, the knob which fastens R and U together. A, fig. 45, shows the collecting tube after the water sample is pro- perly taken ; and C, another form of sampling tube. The total weight of the apparatus is about six pounds, and it is thus self-sinking. A complete vacuum should not be made in the tube, because it is not desirable that the latter should be entirely filled with water. There is always water enough left in the small tube (A) to shut off the ex- ternal air. Bottle for Immersion-Oil and for Canada Balsam.* — Herr A. Meyer has invented a glass dropping-bottle which appears to be very suit- able for immersion-oil and for Canada balsam. Its construction and appearance will be easily understood from the above illustration (fig. 46), from which may also gathered that it is dust- proof, and that if upset, the contents will not run out. Elask for Bacteria and High Tension. — Mr. F. J. Reid sends the accompanying sketch (fig. 47) of a flask which he has found most use- ful with bacteria and high tension currents. Its advantage consists in its having the short neck at the side, into which a thermometer can be * Zeitsclir. f. wiss. Mikr., xiv. (1897) pp. 174-£ (3 figs.). Fig. 47. ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 581 inserted. Witli this flask there is no danger of injury to the bacteria by heating the culture through overcharge of current; any rise ot tem- perature is indicated by the current being cut off when this becomes excessive. . Compressorium.* — Prof. H. E. Ziegler describes his circular form of compressorium, through which a current of fresh water is made o flow and which has already been figured in this Journal. He also de- scribes a rectangular form constructed on the same principle hut large enough for the examination of relatively large objects, e.g. frog-larvae and small fishes. Heating Arrangement for Compressorium.t— Hr. R. Kantorowicz describes an arrangement for warming to a definite temperature the Fig. 48. water which is to he passed through Ziegler’s compressorium. + The vessel shown in the figure (fig. 48) contains a quarter of a litre ; into it * Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 145-53 (4 figs.). Of; th^s Journal c 759- 1895, p. 367. f Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 154 7 (2 fiQs.), P' \ Of. this Journal, 1894, p. 759 ; 1895, p. 367 ; and preceding abstract. 582 SUMMARY OF CURRENT RESEARCHES RELATING TO water flows by the tube a as quickly as it flows out through h to the compressorium. As the water does not remain long in the heating apparatus, it is not deprived of much of its dissolved air. A thermo- meter and thermostat also dip into the vessel. Another form of apparatus suggested by Prof. Ziegler consists of a long glass worm contained in the heating apparatus. As the water passing through this worm does not acquire the same temperature as the bath, its temperature is taken before it enters the compressorium. New Knife-holder for Microtomes.* — Prof. S. Apathy gives the following requirements for a perfect knife-holder for a sliding micro- tome:— (1) It must hold the knife quite firmly ; (2) the knife-edge may be set at any desired angle in the plane of motion ; (3) the knife-edge to be parallel to the plane of motion ; (4) the blade of the knife may be inclined at 0°-20° ; (5) the knife may be taken out of the holder and replaced again in exactly the same position. A holder satisfying these conditions — especially (2) and (4) — is described in detail. The in- clination of the knife to the plane of motion is effected by means of wedges. Cheap Condensing Lens. j — Instructions are given for making a cheap mount for a bull’s-eye condenser. A spectacle maker’s cataract lens is fixed by sealing wax in a loop made from a strip of metal ; this is attached by a wire passing through a cork to a vertical wire on a wooden base. (4) Photomicrography. Simple Apparatus for Photomicrography.]: — Mr. M. J. Golden de- scribes a simple wooden base, consisting of a long board, to which are attached a shelf to hold the Microscope, and a sliding piece with a pair of brackets to carry the camera. A heavy cloth funnel connects the Microscope and camera. (6) Miscellaneous. Diamond for Cutting Glass Discs.§ — Dr. C. J. Cori describes a simple and cheap apparatus for cutting glass discs of various sizes, which are always of use in laboratories. It is constructed on the principle of the beam-compasses. The fixed centre consists of a wooden cylinder of 2 cm. diameter, held to the glass by wax ; about this rotates the hori- zontal prismatic beam, which carries a block holding the diamond. Annuli of glass may be cut with the apparatus. B. Technique.|| (1) Collecting Objects, including Culture Processes. Closing Fishing Net.1T — Dr. C. J. Cori describes a form of net which may be opened at any depth, and, after being trawled for any required time, closed again, thus enabling the organisms from any depth to be * Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 157-74 (9 figs.). t The Microscope (Washington), v. (1897) pp. 109-11 (1 fig.). j Tom. cit., pp. 103-4. § Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 175-7 (1 fig.). || This subdivision contains (1) Collecting Objects, including Culture Pro- cesses; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; (4) Staining and Injecting; (5) Mounting, including slides, preservative fluids, &c. ; (6) 'Miscellaneous. ^ Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 178-84 (3 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 583 collected. Fig. 49 a shows the mouth of the net closed. By letting fall the weight Gf, the lever H' releases the bolt R', which in turn releases the ring r', and so opens the mouth of the net as shown in fig. b. The mouth of the net, which has a width of 30 cm., is made of hinged metal bars V Jcl, contained in the sliding frame Vs. To close the net again, the larger weight G" is let fall ; this, through the lever R" and bolt R", releases the ring r", when the portion Ys of the sliding Fig. 49. frame falls down. The weights G' and G" are made in two parts, so that they can be put on the cable and then bound together by wire round the grooves shown in the figure. The author has used this net in the Traun Lake in Upper Austria, and finds that the plankton is not evenly distributed in depth, but shows a distinct zoning, the depth of which varies with the time of year and day. The apparatus could be slightly modified for deep sea purposes. 1897 r2 S 584 SUMMARY OF CURRENT RESEARCHES RELATING TO Mud Collector.* — Dr. C. J. Cori describes an apparatus for collect- ing tbe fauna from the surface of mud at the bottom of ponds. The glass rod R (fig. 50) is fixed to a bamboo rod, and is provided with a tightly fitting cork K, and an indiarubber ball B. On pulling the cork out by the string S, the escape of air causes the water to rush into the tube ; on further pulling the string, the mouth of the tube is closed by Fig. 50. the ball B. A form with a metal, in place of a glass, tube is figured. A further modification, suggested by Prof. Hatschek, for use with a cable in deep water, is described. A greater lowering of the line than shown in fig. 51 a, causes the projection Z on the tube to become dis- engaged from the weighted hook H, as seen in fig. b. When the line is pulled, the cork is withdrawn from the tube, and a further pull causes the tube to be closed again by the india-rubber ball, as in fig. c. Cultivation of Amoeba. f — According to Prof. P. Frosch, living bacteria are necessary for the proper growth and sustenance of Amoebae, though certain media are more suitable than others. The one preferred is composed of 0*5 grm. agar, 90 grm. tap water, and 10 grm. alkaline bouillon. Upon this, luxuriant cultures of an Amoeba derived from garden earth were constantly obtained. In these bacteria were always demonstrable, and the author’s view is that successful cultivation of Amoeba depends almost entirely on the bacteria supplied. Silk-Glue as a Medium for tlie Cultivation of Bacteria.J— In raw silk there exists a peculiar adhesive substance which imparts to the * Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 184-9 (3 figs.). t Centralbl. Bakt. u. Par., lte Abt., xxi. (1897) pp. 926-32. X Op. cit., xxii. (1897) pp. 122-4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 585 silk filament its firm hard character and grey colour. This “ lime ” is soluble in boiling water, and when cold sets to a greyish jelly, forming, according to Herr G. Marpmann, a good cultivation medium for many bacteria. Not only do air and water bacteria grow well on the silk glue, but mould fungi, and the peptonising organisms also, though the medium is but little liquefied by the latter. Owing to the fact that silk glue contains sulphur, it forms a suitable medium for the cultiva- tion of thiophilous bacteria. The addition of salt, sugar, or pepton to the medium is not necessary. Growth of Diphtheria Bacilli on different Media.* — Dr. G. Michel records the results of an elaborate series of experiments made for the purpose of comparing the growth of diphtheria bacilli on the following media : — Glycerin-agar. Loeffler’s bullock-serum, normal bullock-serum, Loeffler’s horse-serum, and normal horse-serum. Of these, Loeffler’s t Centralbl. Bakt. u. Par., lte Abt., xxii. (1897) pp. 259-73 (5 figs.). 2 s 2 586 SUMMARY OF CURRENT RESEARCHES RELATING TO horse-serum proved to be the best, the second place being taken by glycerin-agar ; for out of 200 cases examined, the former gave positive results in 137 instances, the latter in 122. The aspect of the growth in the five media inoculated from the same case is well shown in photo- graphs. From these it would seem that the glycerin-agar was the best medium, though the Loeffier horse-serum runs it close. The Loeffler’s serum consists of 3 parts serum and 1 part bouillon, with 1 per cent, pepton, 0 • 5 per cent, salt, and 1 per cent, grape-sugar. Egg-yolk Agar for Cultivating Gonococcus.* — Herr Steinschneider makes a nutrient medium for cultivating Gonococcus in the following way. An egg yolk is beaten up with thrice its bulk of sterile water. Twenty grm. of this are mixed with 10 grm. of 20 per cent, solution of biphosphate of soda and 90 grm. of 2 * 5-3 per cent, agar, and the mixture, having been poured into tubes, is allowed to set. On this the coccus can be cultivated directly from the purulent secretion. (2) Preparing: Objects. Method of Preparing Anatomical Specimens.! — Dr. N. Melnikoff- Easwedenkoff places the specimens directly they are removed from the body in a solution composed of 10 formol in 100 water for 24-18 hours. Then are added 5 to 10 parts (per 100 of fluid) of sulphuretted hydro- gen, or 0*5-1 part of peroxide of hydrogen. The preparation is after- wards immersed for 3 or 4 days in 60-80 per cent, of alcohol, and finally in a mixture of 20 parts glycerin, 15 acetate of potash, and 100 parts of water. To the first fixative fluid the author adds various substances, which exert some influence on the fixation of certain tissues, such as hydroxylamin, hydrochinon, pyrocatechin, and certain acetates, e.g. those of aluminium, copper, calcium, barium, and magnesium. Preparation and Use of Klein’s Fluid for Separating Minerals and Diatoms.J — Of the solutions of high specific gravity, Klein’s fluid is to be preferred, says Herr Marpmann, as its sp. gr. is 3’6, and it is not poisonous, while Thoulet’s fluid and Eossbach’s solution are extremely poisonous and of less specific gravity. Klein’s fluid consists of boro- tungstate of cadmium, and is prepared by dissolving 1 part of tungstate of soda in 5 parts of water, adding 1 • 5 parts of boracic acid, and boiling until crystals of borax precipitate. The lye is inspissated until glass fragments will lie on the surface, and then 0 * 3 parts of a solution of barium chloride added, after which it is acidified with hydrochloric acid. In this way boro-tungstate of barium is formed, the salt separating out in tetragonal crystals, which are purified by repeated re-crystallisation. By mixing boiling solutions of the barium salt and of cadmium sulphate, cadmium boro-tungstate is obtained. This is soluble in 0 • 1 per cent, of water, the fluid having a specific gravity of 3*28 at 15° C. By evapo- ration and re-crystallisation the specific gravity is raised to 3*6 at 75°, and the salt can only be used when warm. The vessels suitable for separation of the various constituents are, a glass funnel, capable of holding 100 ccm., and having a stopcock at the lower end of the stem, * Berlin. Klin. Wochenschr., 1897, No. 18. See Centralbl. Bakt. u. Par., ltB Abt., xxii. (1897) pp. 104-5. f Comptes Rendus, exxiv. (1897) p. 238. See Zeitschr. f. angew. Mikr., iii. (1897) p. 115. % Zeitschr. f. angew. Mikr., iii. (1897) pp. 150-2. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 587 or a flask of similar capacity, with a long narrow neck, which is marked off in divisions of 0 * 1 ccm. The powdered material and the hot solu- tion are placed together in one of these vessels and then water added drop by drop, the vessel being carefully shaken after each drop. In this way the fluid is very slowly diluted, and the specific gravity lowered so gradually that it is possible to separate substances from one another the specific weight of which differs by 0*01 p.c., or less. As soon as the density corresponding to that of the mineral or of the organisms is reached, the particles sink slowly to the bottom of the neck of the funnel. When the supernatant fluid is perfectly clear, the tap is turned, and the sediment allowed to flow very slowly into watch- glasses. This takes from 12-24 hours, and as the fluid has cooled, more water must be added, and fresh sediments removed as they form. As diatoms consist of the same chemical substance, silicic acid, with but slight admixture of other chemical compounds, as soon as the density of silicic acid is reached, all siliceous bodies are deposited, and it might be supposed that all the diatoms will come down together. This, however, is only theoretically the case ; for, as a matter of fact, the larger diatoms are deposited sooner than the smaller sorts ; so that an expert manipu- lator has it in his power to collect the different kinds by themselves, aud unmixed with other varieties. The material collected is washed with water, and further purified by sedimentation. The Klein’s fluid which has been used is separated by the addition of some cadmium and by eva- poration, and may be used over and over again. Modification of Golgi’s Method.* — The energetic action of aldehyds on silver salts suggested to Dr. F. Kopsch a favourable modification of Golgi’s method. The fixative employed is a mixture of 40 ccm. of a 3*5 per cent, solution of potassium bichromate and 10 ccm. of formalin. After 24 hours’ immersion in this fluid, the objects are removed to pure bichromate solution, and in 2-3 days transferred to 0*75 per cent, nitrate of silver solution for 3 to 6 days. Nervous tissue stains well without suffering from precipitates. Schaper’s Reconstruction Method.f — The main difference between Dr. A. Schaper’s method and that of Born is that the base line of the sec- tions is not at a distance from the section of the object, but is on the edge of the section itself. The embryo is first saturated with paraffin to prevent its drying and shrinking afterwards. It is then taken from the bath and fixed to a piece of Bristol board, after which it is sketched or photo- graphed. It is then transferred to the bath, and a line drawn on the sketch or photo just touching the head, thus including the figure in a right angle. A similar angle is drawn on a piece of cardboard that fits into the imbedding-box. The latter is filled with melted paraffin and the embryo oriented so as to correspond with the position of the figure in the sketch. After hardening, the mass is sectioned. In sectioning, the plane of the section must be perpendicular to the median plane of the embryo. The sections should be 20 //, thick. Sketches of the mag- nified sections are made on paper and transferred to wax sheets ; but before doing so a pencil-point is made on the dorsal side of the sketch * Anat. Anzeig., xi. (1896) pp. 727-9. f Zeitschr. f. wiss. Mikr., xiii. (1896) pp. 446-59 (10 figs.). See also Amer. Natural., xxxi. (1897) pp. 746-8 (2 figs.). 588 SUMMARY OF CURRENT RESEARCHES RELATING TO in the median plane, and sometimes also one in the same plane on the outline of the surface of some central organ. The photo or sketch is then enlarged on a sheet of Bristol board, to correspond with the magnification of the sections and the enlarged figure. If only an enlarged model of the entire embryo is desired, it is merely necessary to arrange the wax sections within the Bristol board outline, and then smooth off the outer surface with a warm modelling tool. If, however, it be desired to reconstruct an internal organ, the process is more complicated, for then the second guiding-point (that on the surface of some central organ) is necessary. “ In cutting out of the wax plates the outlines of the sections of the organ to be reconstructed, this point, along with that on the dorsal surface, is cut out so as each to form a point of the piece of wax that remains connected with the sections of the organs by bridges of wax.” When the series of wax sections has been cut out, they are arranged in their proper places on the Bristol board, care being taken that the two guide-points fall within the plane of the Bristol board, and that the line passing through them is perpendicular to the dorsal line. When all are in place, all that remains is to smooth off the outer surface of the model. Method of preparing Rotifers.* — M. N. de Zograf has used a modi- fication of Rousselet’s earlier method for narcotising Rotifers with cocain, and staining with osmic acid. The animals are first treated with an aqueous solution of hydrochlorate of cocain, which is added drop by drop to the specimen fluid. The methyl-alcohol used by Eousselet is con- tinued. As soon as the animals begin to draw in their antennae, a few cubic centimetres of dilute osmic acid are added, and in from 2-4 minutes mixed with 10 per cent, wood-vinegar (pyroligneous acid). The fluids are slowly poured off and replaced by alcohol. The animals do not lose bulk, and may be preserved in glycerin or mounted in balsam. Demonstrating presence of Flagella of the Plague Bacillus.^ — Mr. M. Gordon, working under the direction of Dr. E. Klein, began with a gelatin culture of the plague bacillus. From this a bouillon culture was made and incubated at 37°, and small doses thereof were injected subcutaneously into a guinea-pig. The animal died in two days, and characteristic organisms were found in the lymphatic glands and spleen. Plate cultivations were made from the heart-blood, and typical colonies reinoculated on oblique agar. After 20 hours5 incubation at 37°, cover- glass preparations were stained by van Ermengem’s method. In suc- cessful preparations rodlets are found which possess at one end a spiral flagellum about double the length of the organism. Occasionally a second spiral flagellum at the same end, but attached laterally, is present. The flagella are only stained with difficulty, apparently owing to the presence of some viscid substance by which the organisms are invested. Slight movements are visible in hanging drop preparations of agar cultures. Decalcifying and Desilicating Sponges.J — Dr. E. Rousseau de- calcifies sponges which contain much lime salt, such as Leuconia, Leu- candra , Leucosolenia , Sycon, &e., by first hardening pieces the sides of which are not longer than 2 cm., and then imbedding in celloidin. * Comptes Rendus, cxxiv. (1897) p. 285. See Zeitschr. f. angew. Mikr., iii. (1897) p. 116. f Centralbl. Bakt. u. Par., lte Abt., xxii. (1897) p. 170. J Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 205-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 589 The imbedded pieces are then immersed for 12-24 hours in a mixture of spirit and nitric acid (15-40 parts HN03 sp. gr. 1*4 and 100 parts of alcohol 85 per cent.). Each piece requires at least 20 ccm. of the fluid. The pieces are next transferred to 85 per cent, alcohol which contains some precipitated carbonate of lime, until every trace of acid is removed. They are then placed in 85 per cent, spirit, and sections made. For desilication, sponges are treated with fluoric acid, after pieces have been imbedded in celloidin as in the previous method. Of course, all the vessels and instruments used must be made of, or covered with caoutchouc or paraffin. A piece of sponge imbedded in celloidin is placed in a caoutchouc capsule, having a lid, and containing at least 50 ccm. of alcohol. To this commercial hydrofluoric acid is added drop by drop up to 20 or 30 drops, according to the amount of silica in the sponge. The desilication takes from one to two days. The pieces are then placed in 85 per cent, alcohol containing some lithium carbonate. If there be any precipitate in the tissue, it may be subsequently removed with hydrochloric acid alcohol. By this procedure very good sections of TetJiyx, Suberites, Thenia , Geodia, Beniera , &c. can he obtained. (3) Cutting, including Imbedding and Microtomes. Improved Cathcart Microtome.* — Herr C. Elbe describes slight improvements in the Cathcart microtome (fig. 52). To prevent slipping * Zeitschr. f. angew. Mikr., iii. (1897) pp. 147-9 (1 fig.). 590 SUMMARY OF CURRENT RESEARCHES RELATING TO of the knife on the strips of glass, ra small metal flange projects upwards for the knife to rest against. The glass slips may he easily turned or replaced when worn. The micrometer screw gives a movement of 10 [x. The object-holder is strengthened, and a larger ether flask is provided. Weigert’s Microtome.* — Herr C. Erbe gives detailed instructions on the method of using Weigert’s sliding microtome. An improvement of this instrument is introduced by making the slides double. Fig. 53. Microtome with Metzner’s Double Support Guidance. — Herr C. Erbe, of Tubingen, has produced a microtome (fig. 53) with a double support, for which he claims increased firmness both for the object and for the knife. (4) Staining- and! Injecting-. Notes on Fixation, Alcohol Method, Stains/ &c.f — Herr G. Eisen highly commends the following mixture for fixing: — Platinum chloride 0*5 percent., 50 parts; iridium chloride O’ 5 percent., 50 parts; glacial acetic acid 1 part ; but has found that the iridium chloride alone is supe- rior. The solutions are iridium chloride 0’5 per cent., 100t; glacial acetic acid, 1; and iridium chloride 0*2 per cent., 100; glacial acetic acid, 1. Small objects should he kept immersed for six hours or so. A prolonged stay in the fixative is stated to be harmless. After removal from the fixative, the objects are placed for a few hours in dis- tilled water. According to the author the alcohol method for fixing sections to the slide is successful enough if performed in the following way. The slide is flooded with 80 per cent, alcohol. The paraffin sections are placed thereon, and removed to the shelf top or side bench of the bath, the water in which is kept at 55°. The sections at once stretch out, and then the slide must be removed to the work-table, when the alcohol is poured off, and the sections [arranged. Two strips of thick blotting paper, the same size as the slide, are placed on the sections, the strip next the sections being moistened with 80 per cent, alcohol, the upper one kept dry. A roller, used with considerable force, is then passed [ * Zeitschr. f. angew. Mikr., iii. (1897) pp. 1G9-73 (l*fig.). t Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 195-202. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 591 over the blotting paper, and thus the sections are firmly fixed to the slide. The sections are then brushed over with a soft large camel’s hair brush, and returned to the shelf of the water-bath, on which are placed several layers of black cardboard. The sections dry in from ten minutes to an hour, and may then be manipulated with impunity, or stored away for future use. Brasilin , says the author, is a very good stain, in many respects being superior to haematoxylin. It should be mixed in the same way as Bohmer’s haematoxylin. After a few weeks the stain ripens into a deep red, with copious precipitate of blue flakes insoluble in water. The flakes are collected in a filter, and dissolved in 95 per cent, alcohol, and 15 per cent, of glycerin added. This solution is superior to the original solution, and stains nuclei a deep red. Iron lisematoxylin. The sections are immersed for 12 hours or more in liq. ferri sulf. oxidati diluted at least five times. Before being placed in the haematoxylin bath the sections should be washed for at least one minute in water. The saturated aqueous solution, which should contain 10 per cent, of alchol, is diluted for use with from ten to twenty times the amount of distilled water, and the sections immersed therein for 12 hours or more. Differentiation is then made with the same liq. ferri greatly diluted, or with 25 per cent, (or less) formic, acetic, or other acid, or with mixtures of acids and liq. ferri. In using this method it is important to remove all traces of alcohol from the sections before they are placed in the liq. ferri. Tliionin-ruthenium-red. This combination will produce opposite re- sults according to the length of time occupied by the thionin-staining, or the age of the ruthenium mixture. (1) Stain first for 5 minutes with aqueous 1 per cent, solution of thionin with 10 per cent, of alcohol. Binse in distilled water, and then put on the section a few drops of ruthenium-red (made by dissolving in 80 per cent, distilled and filtered water, 10 per cent, absolute alcohol, and 10 per cent, glycerin). When the cells in mitosis exhibit a red cyto- plasm and dark blue chromosomes, as observed under the Microscope, the differentiation is checked. Dehydrate with absolute alcohol, clear with pure fresh bergamot oil, and follow at once with xylol. (2) Stain for 12-24 hours in a very weak solution of thionin (a couple of drops of 1 per cent, solution in a Naples jar of water). Binse in distilled water, and differentiate as before with ruthenium-red. De- hydrate and clear as before. By the first procedure the chromosomes are stained blue, by the latter red, or reddish-brown, and so on. Gum-thus. This substance is a gum from a Binus indigenous to the Eastern United States ; it is dissolved in xylol ; it dries quicker, and gives clearer and better definition, than Canada balsam. It has the additional merit of being much cheaper than balsam. Combined Method of Fixing and Staining Microscopic Prepara- tions.*— Herr M. B. Wermel has combined the fixation and staining of blood and muscle by the use of the following solution : — 1 methylen- formalin (saturated alkaline methylen-blue, 30 ccm. ; 2*5 per cent, aque- * Mcdizinskoje Obosrenje, May 1897. See Centralbl. Bakt. u. Par., 1‘® Abt., xxii. (1897) p. 419. 592 SUMMARY OF CURRENT RESEARCHES RELATING TO ous solution of formalin, 100 ccm.) ; (2) eosin-formalin (eosin 1 percent, in 60 per cent, alcoliol, 100 ccm. ; formalin 10 per cent, aqueous solution, 20 ccm.) ; (3) metliylen-blue formalin (saturated aqueous solution of methylen-blue, formalin 4 per cent, aqueous solution). Blood preparations are first dried in the air, then stained for two minutes in solution 2, tlie excess of stain removed, and next stained for 2 minutes with solution No. 3, after which they are washed in water and examined. For Gram’s method, gentian- violet-formalin was used, i.e. 10 ccm. of 10 per cent, alcoholic solution of gentian-violet, and 100 ccm. of 2*5 per cent, aqueous solution of formalin. For staining gonococci the film need not be fixed in the flame, but merely treated at once with eosin-formalin for 2 minutes, and afterwards with a satu- rated aqueous solution of metliylen-blue. Double-Staining Vegetable Tissue.* — Herr H. Pfeiffer recommends a mixture of hsemalum and naplithylamin yellow for staining vegetable tissue, as it differentiates the lignified from the non-lignified tissue. The sections fixed in alcohol are placed in a mixture of equal parts of satu- rated aqueous solution of haemalum and naphthylamin yellow, for 30 to 50 minutes. On removal they are washed in water for one or two minutes, placed on a slide, dehydrated, and mounted in the usual way. The ligneous tissue is stained yellow, the non-ligneous parenchymatous tissue violet. Triple Stain for Animal Tissues.! — Herr J. L. Graberg uses the following solution for staining sections of animal tissue : — 1 per cent, aqueous solution of Bordeaux red, 400 ccm. ; 0 • 5 per cent, aqueous solu- tion of thionin, 200 ccm. ; 1 per cent, aqueous solution of methyl-green with 25 per cent, alcohol, 300 ccm. The solution is filtered, and the sections immersed therein for 24 hours, after which they are thoroughly washed in 93 per cent, alcohol to which a few drops of acetic acid have been added, until they assume a reddish hue. The sections stain best when the material has been fixed in saturated solution of sublimate in 0 • 7 per cent, salt solution. Method of Staining Nervous Tissue for Microscopic Purposes-! — Dr. Vastarini-Cresi stains the central nervous system for microscopic purposes by immersion in formalin (13 per thousand), for 2 weeks, the meninges being removed on the second or third day. Sections from 3-5 cm. thick are placed in water, or better in 40 per cent, alcohol, for 12— 24 hours, and then removed to 0*75 solution of silver nitrate, wherein they may remain for an indefinite period. The preparations are after- wards treated with water and 70 per cent, alcohol. Tissue thus prepared shows well the relations between the white and grey substances. C6) Miscellaneous. Demonstrating the Electric Organs of the Ray.§ — Herr E. Ballo- witz examined the electrical organs of the common ray, Raja clavata L., and found that not only the nerve-endings, but other structural elements * Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 202-5. t Op. cit., xiii. (1896) pp. 460-1. X Rif. Meet., Feb. 14, 1896. See Brit. Med. Journ., 1896, i. Epit., 303. § Zeitschr. f. wiss. Mikr., xiii. (1896) pp. 462-7. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 593 of the electrical organs, usually only seen with great difficulty, were ren- dered perfectly clear by Golgi’s method. The preparations were stained in chrom-osmic acid (4 : 1), and, after 3—4 days, were washed in dilute silver nitrate solution, and then immersed for 1-3 days in 0*75 silver nitrate. Concentration of Therapeutic Sera by Freezing.* — Prof. 0. Bujwid has been able to obtain strongly concentrated diphtheria and tetanus sera by means of freezing. The ice is devoid of antitoxins ; these, to- gether with other constituents of the sera, remaining in solution. On freezing a bottle containing serum, the latter separates into ice crystals and a small quantity of brownish fluid. After thawing at room tempera- ture, the contents of the bottle are found to have separated into two layers; the upper, which is quite colourless, contains only a small quantity of solid matter, and is practically water. Its antitoxic action is almost nil. The lower layer is of a yellow colour, perfectly clear, and contains all the antitoxins. After freezing two or three times, a serum is obtained which is 2J to 3 times more concentrated than the original, so that 1-2 ccm. contain 1000 antitoxin units. Pastes and Cements for General Purposes.! — (1) Gum arabic, 4 parts ; starch, 3 parts ; sugar, 1 part. Dissolve the gum in water sufficient to take up the starch, add the sugar, and heat the whole on a water-bath until the starch is completely dissolved. (2) Collodine is a paste made by treating starch with water rendered strongly alkaline. (3) Triticine is a paste made by dissolving equal parts of dextrine and starch in water and then heating. A little glycerin is added to make the paste pliable and elastic when dry, and a little boric acid or thymol to prevent fermentation. (4) Gum arabic, 70 parts; water, 200 parts; aluminium sulphate, 2 parts. Dissolve the aluminium sulphate in some of the water, the gum in the rest, and mix the two. (5) Gelatin, or best glue, 2 parts; water, 6 parts. Soak the gelatin in the water until it is soft throughout, then melt in a water-bath. Add 1-2 parts of chloral hydrate, and continue to heat gently for some time. (6) Cover 100 parts of gelatin with water, and let stand until the gelatin is saturated. Then melt in water-bath and add 150 parts alcohol, 500 parts water, 50 parts glycerin, and 20 parts carbolic acid. This makes a very powerful cement. Bronzing of Copper .} — For bronzing copper, Herr Mondil gives the following procedure : — After the surface has been thoroughly cleaned, it is brushed over with a mixture composed of 20 parts by weight of castor oil, 80 parts alcohol, 40 parts soft soap, and 40 parts water. The mor- dant is left on the metal until it is sufficiently stained. The surface is then dried with hot saw-dust, and afterwards covered with a thin layer of varnish. * Centralbl. Bakt. u. Par., lte Abt., xxii. (1897) pp. 287-8. t Amer. Mon. Micr. Journ., xviii. (1897) pp. 296-8. + Centralztg. f. Opt.u. Mech., 1897, p. 4. See Zeitschr. f. angew. Mikr., iii. (1897) p. 118. 94 SUMMARY OF CURRENT RESEARCHES. Browning Iron or Steel.* — A correspondent gives the following method for browning iron or steel to protect them from rust : — 2 parts of crystallised iron chloride, 2 parts of chloride of antimony, and 1 part of gallic acid are dissolved in 4 parts of water. The object is then smeared with the solution applied with a rag or sponge, and is al- lowed to dry in the air. The procedure is repeated several times until the colour is sufficiently dark. The object is then washed with water, dried, and the surface rubbed with boiled linseed oil. The antimony chloride should be quite neutral. * Centralztg. f. Opt. u. Mech., 1897, p. 4. See Zeitschr.f. angew. Mikr., iii. (1897) p. 118. 595 PROCEEDINGS OF THE SOCIETY. MEETING Held on the 20th of October, 1897, at 20 Hanover Square, W., The President (E. M. Nelson, Esq.) in the Chair. Pursuant to notice given at the preceding meeting, June 16th, the President declared the meeting to be made special for the consideration of the following addition to the Bye-laws, to be called Bye-law No. 65 : — “ The Council shall, at the Annual Meeting, propose a Fellow of the Society to act as Curator of the instruments, tools, and such other objects as may from time to time be confided to his care ; he shall be elected by the Society, and shall make an annual report of the condition of the objects under his charge.” As this was a new bye-law, its insertion would involve the re-numbering of those which followed. The President having moved the adoption of this proposed new bye- law from the chair, it was seconded by Mr. J. J. Yezey, and being put to the meeting, was declared to be carried unanimously, and was ordered to be added to the list of Bye-laws accordingly. The business of the ordinary meeting was then proceeded with, and, in the absence of both the Hon. Secretaries, the minutes of the meeting of June 16th last were read by Mr. Yezey, and having been duly con- firmed, were signed by the President. The following Donation was announced : — From Den Norske Nordkavs Expedition 1876-78. \ The Editorial Committee of the Nor- XXIV. Botanik, Protophyta, by H. H. [ wegian North- Atlantic Expedition , on Grau. 36 pp. and 4 pis. (4to, Chris- j behalf of His Norwegian Majesty’s tiania, 1897.) j Government. Mr. Yezey remarked that this was a valuable donation, and on the motion of the President a special vote of thanks to the donors was unanimously carried. The President said he had great pleasure in bringing to the notice of the Fellows of the Society the most excellent and valuable work which their Treasurer, Mr. Suffolk, had been doing, namely, the compilation of a complete catalogue of about 4000 slides in the Society’s cabinet. Mr. Suffolk had been for years working at these slides, putting right where possible those which were going bad from age or imperfect mounting, and having thoroughly overhauled them, he had produced the very valuable catalogue which he now had the pleasure of laying upon the table. He felt sure that when they knew what an amount of care and trouble had been expended upon the production of this catalogue, they would join with him in a very hearty vote of thanks to Mr. Suffolk for this very excellent piece of work. Carried by acclamation. 596 PROCEEDINGS OF THE SOCIETY. Messrs. R. and J. Beck sent for exhibition two new Microscopes and a new form of Centrifuge, which were described by Mr. Hill. The Microscopes were in most respects similar to their well-known “National” pattern, but in place of the circular stage they were fitted with a large square stage ; one had a stand of the usual form, the other was made to fold and pack away in a case of the smallest possible size to contain the instrument and its accessories, for convenience and porta- bility. The centrifuge was a very well made instrument for separating and depositing rapidly matter held in suspension by various fluids ; it had been found efficient in the separation of the red corpuscles in blood, rendering it easy in this way to determine their relative pro- portion in a given quantity. The separation of cream from milk in two small glass tubes was shown in the room, the proportionate quantity in a cubic centimetre being read off at once on a scale. Mr. Hill also exhibited two Hand-Magnifiers, which had been constructed on a new formula, and were said to be perfectly aplanatic. Thinks were voted to Messrs. Beck for their exhibits. The President said there was an exhibition on the table consisting of part of a collection of Insects’ Eggs presented to the Society’s cabinet some years ago by Mr. J. T. Norman. The Society were greatly in- debted to Messrs. Swift and Son, who had lent the necessary Microscopes to display this exhibition, and he was sure the Fellows would join him in expressing thanks to Messrs. Swift. The President said that the Council had felt it their duty, in common with all the other learned Societies, to forward a message of congratula- tion to Her Majesty the Queen on the completion of the sixtieth year of her reign. An address had therefore been prepared and forwarded, and a reply had been received thereto. The text of both address and reply were read to the meeting as follows : — “ To the Queen’s Most Excellent Majesty. May it please your Majesty, — We, your Majesty’s loyal and obedient subjects, the Fellows of the Royal Microscopical Society of London, most humbly beg to be allowed to offer to your Majesty the assurance of our sincere congratulations upon the completion by your Majesty of the sixtieth year of your Majesty’s reign, and of our earnest share in that great outburst of affec- tionate loyalty which has sprung so unmistakably from all peoples and all lands included within the limits of your Majesty’s vast Empire. It is to the Fellows of the Eoyal Microscopical Society matter of gratification and pride that the origin of the Society closely corresponds in point of time with the beginning of your Majesty’s reign, that the usefulness of the Society was recognised and its prestige enhanced by being incorporated by Royal Charter in the year 1866, that His Royal Highness the Prince of Wales has for years held the office of Patron, and that the labours of the Society may accordingly claim to have shared, however humbly, in that marvellous progress in Science, in Arts, and general PROCEEDINGS OF THE SOCIETY. 597 knowledge, which has attended and adorned the successive years of your Majesty’s reign. We fervently trust and pray that the same conditions may long endure, and that long-continued health and strength may he granted to your Majesty. Signed on behalf of the Fellows of the Eoyal Microscopical Society, Edward Milles Nelson. 20 Hanover Square, London, W.” “ Whitehall, 20th September, 1897. I have had the honour to lay before The Queen the loyal and dutiful Address of the Fellows of the Eoyal Microscopical Society of London on the occasion of Her Majesty attaining the sixtieth year of her reign, and I have to inform you that Her Majesty was pleased to receive the same most graciously. I have the honour to be, Your obedient Servant, (Signed) M. W. Eidley. The Secretary of the Eoyal Microscopical Society of London. 20 Hanover Square, W.” Mr. A. W. Bennett said that a valuable paper had been contributed to the Society by Mr. William West and Mr. George S. West, who were known to he such diligent and careful workers that anything from them was sure to be of the highest interest. The paper itself was not, however, one which could be read in detail to the meeting, but it would be a most valuable addition to the literature of the subject, being a list of the Fresh- water Algae of the South of England below a line drawn across the country from Essex to Cornwall, containing a description of many new species and two new genera, and illustrated by two very beautifully drawn plates. He had asked permission to add to this some notes of his own on the freshwater Algae found in the neighbourhood of London, including some rare species met with in the Gardens at Kew. Even in such unpromising localities as the Eegent’s Canal he had found some interesting freshwater Algae. The thanks of the meeting were unanimously voted to Mr. Bennett for his communication. Mr. T. Comber read a paper c On the Limits of Species in the Diatomaceee.’ Mr. George Murray, being called upon by the President for some remarks upon the subject, said it had been a great pleasure to listen to Mr. Comber as one who had such a practical acquaintance with the sub- ject and was also a man of such wide reading. He had hoped, therefore, to get some very welcome ideas upon the matter, for he confessed that he came to the meeting with a great deal of confusion in his mind, and he was afraid he was going away still more confused, for it was with dia- 598 PROCEEDINGS OF THE SOCIETY. toms as with some other groups of plants and with animals, an extremely difficult matter to decide what to regard as a species. For some few years past he had been working at marine diatoms, and had experienced this same difficulty in determining what was really the limit of any particular species, and he had applied to Mr. Comber and to others with only very conflicting results, and he came to the conclusion that there was hardly anything in Nature equal to what existed among diatoms as to confusion of species ; they seemed to run one into the other in such numerous ways, and in lines which branched out in all directions. Numbers of them were found in fossil conditions as far back as the Cretaceous rocks, where some of the same forms were met with which were existing at the present day, and it would therefore be most natural to think that things of such determinate character would at least have well-marked forms ; but they found it was not so. It was to be hoped, however, that light would some day be thrown upon it, and that by working with a strong determination they might perhaps get a little better order infused. The President said their hearty thanks were due to Mr. Comber for his very excellent paper, which he hoped would be a means of reducing the enormous number of species, or at least of checking their increase. He had been doing a little work himself amongst diatoms, but certainly not in naming them ; and it had always appeared to him that the species- namers had troubled themselves too much with outside form rather than giving their attention to the way in which the structure was built up. The thanks of the meeting were unanimously voted to Mr. Comber for his paper. Mr. Vezey said they had received another paper, but this was one which they would agree it would be better should be taken as read, as apart from the illustrations it would scarcely be intelligible. This was by Mr. Chapman, and was Part 10 and conclusion of his series of papers on the Foraminifera of the Gault of Folkestone, with Appendix and Summary. The paper would of course be printed in a future number of the Journal. The thanks of the Society were given to Mr. Chapman for his com- munication. The following Instruments, Objects, &c., were exhibited:— The Society : — The following slides of Eggs of Insects from the Society’s Cabinet : — Moths : Abraxas grossulariata , Magpie ; Acidalia aversata, Ribband Wave ; Biston hirtarias, Brindled Beauty ; Bombyx Mori, Silkworm ; Centra Vinula , Puss ; Crocallis flinguaria, August Oak ; Bylopbila or Balias prasinana, Silver Lines ; Bemerophilia abruptaria, Waved Umbre ; Odonestis potatoria, Drinker ; Orygia anliqua, Yapourer ; Noctua triangulum ; Selenia illustraria , Purple Thorn ; Tortrix sp. ; and Willow Beauty. Butterflies: Cabbage White; Chrysophanus Phlseas , Copper ; Bipparchia Janira, Meadow Brown ; Pontia Brassicse, Large White ; Vanessa Urticse, Tortoise-shell ; Anthomyia (?); Sialis surturalis, Sedge-Fly ; Cimex lectularius. Messrs. R. and J. Beck: — Two new Microscopes; a new form of Centrifuge; and two Hand-Magnifiers. PROCEEDINGS OF THE SOCIETY. 599 MEETING Held on the 17th of November, 1897, at 20 Hanover Square, W. E. M. Nelson, Esq., President, in the Chair. The Minutes of the special and ordinary meetings of 20th October last were read and confirmed, and were signed by the President. The Secretary said that the only donation to the Society (exclusive of exchanges) which he had to report was volume iv. of Dr. de Toni’s 1 Sylloge Algarum.’ The thanks of the Society were voted to Dr. de Toni for this dona- tion. The Secretary said that a vacancy having occurred in their list of Honorary Fellows, it was proposed to elect Mr. Arthur Belles Lee, of Nyon, to fill this vacancy; a nomination paper was accordingly read, and ordered to be suspended until the next ordinary meeting. Mr. J. W. Measures exhibited and described a new binocular dis- secting Microscope, in which a direct image was obtained by means of Porro’s prisms, a further peculiarity being that the image in each eye- piece was formed by a separate objective, the two objectives being fitted together at an angle which, at the focal distance, admitted of the axis of each passing through the same point. There was an arrangement by which the distance apart of the eye-pieces could be regulated to suit the eyes of the observer, and provision was made for both dark and light ground illumination. The image seen was ortho-stereoscopic, and hand- rests were fixed on either side of the stage, as was usual in the case of dissecting Microscopes. The Microscope was made by Zeiss. Mr. A. D. Michael inquired up to what power this arrangement was available, and whether there was not a loss of light consequent upon the use of these prisms. He fancied that the use of an instrument of this kind would be confined to dissection with low power, and he feared that the loss of light would prove a difficulty if higher powers were at- tempted. For large objects and under low magnifying powers it would probably be a very handy instrument, but for very delicate dissections under high powers, he doubted if it would be successful. Mr. Measures said this Microscope was only intended for use in dis- secting with low powers. He did not know how far it would be possible to work it with objectives of higher pow'er than those on the Micro- scope. Mr. Beck asked at what angle the two objectives were inclined towards the object. After inspection, he thought the angle was about equal to that of the eyes placed about 6 in. apart, and that it would consequently give undue stereoscopic effect. The President said that some years ago he felt very much interested in this kind of thing, and in the course of his experiments he made a 1897 2 T 600 PROCEEDINGS OF THE SOCIETY. binocular Microscope on the Cherubin d’Orleans model, in wbicb lie used two Seibert’s objectives. He wanted to see wliat difference there would be between the stereoscopic effect produced in this way and that obtained by Mr. Wenham’s arrangement. The result was exceedingly- pleasing ; he never saw anything so nearly approaching the natural beauty of the object as the effect which he obtained by viewing it through two objectives in this manner. When the Porro prisms came out, he thought that they could be used for the purpose to which they were applied in this Microscope. It was, as Mr. Michael had surmised, only available for low powers, but extremely beautiful effects could be got out of it. During the vacation he had stumbled across a delightful old book, which was partly devoted to optics, and partly to magic and philosophy. He had thought the Porro prism was a new thing, but to his surprise, he found it was described in this old book, dated 1702. He had also been under the impression that Jordan’s sunshine recorder was some- thing which belonged to the 19 th century, but on looking through this book, there it was, with a number of ingenious modifications. Telescope sights for guns he also thought to be a new invention, but these were there too, and not only fitted to guns, but also to cannons. Pere Cherubin d’Orleans had in 1671 anticipated the drawing panto- graph which Dr. Isaac Roberts described in the ‘ Monthly Microscopical Journal,’ vol. viii, page 1, July 1872. Cherubin d’Orleans (whose real name was Francois Lassere) was the inventor of binocular Microscopes and telescopes, and consequently of the opera and field-glasses of the present day. He was a man who was greatly in advance of the time in which he lived. In his optical book he describes the apparatus, and methods of grinding and polishing lenses. The President made some remarks on an interesting old Microscope which had belonged to Sir David Brewster, and which Mr. C. L. Curties had brought down for exhibition. It was provided with six powers, amongst which was the original Garnet lens. Mr. J. E. Barnard read a paper ‘ On the Application of the Electric Arc to Photomicrography,’ in which he described the successful arrange- ments devised by himself and Mr. Carver. In illustration of the subject, an image of the carbon points with the arc between them was projected upon a screen, and the most effective position and distance thereby demonstrated. The difference between the action of the continuous and the alternating current was also shown in the same manner. Photographs of the lamp and its accessories, and photomicrographs taken in the manner described, were also shown upon the screen. Mr. Yezey said he understood that Mr. Barnard did not claim a hand-fed arc lamp as a novelty, because such lamps had been in use for some time in lantern work, where it was essential for the source of light to be kept central to the condenser. He referred to Mr. Davenport’s patent electric lamp and others which had been designed for this pur- pose. Mr. Barnard said he was quite aware that there were many forms of PROCEEDINGS OF THE SOCIETY. 601 hand-fed arc lamps in use, but the point to which he had endeavoured to direct attention was that hitherto no means of accurately observing the crater and measuring the length of the arc had been available, but with a pin-hole camera such as he had described this was efficiently provided. The President inquired what light was focused upon the object in using the Microscope, also what was about the actual size of the spot of light upon the positive carbon. Mr. Barnard said the direct light from the carbon point was used ; what came through the pin-hole was merely used to indicate the position of the light. The diameter of the brightest part of the crater was about 1 mm. Mr. C. L. Curties said that in the lamp used at Dr. Symes Woodhead’s laboratory on the Thames Embankment, they had crossed lines instead of a hole, and the crater was kept central to these. Mr. T. A. B. Carver had recently seen a large arc lamp at the Royal College of Surgeons, but was surprised to find that, although it was equipped with a lens casting an image of the arc upon a coloured screen, no reference marks were provided by which the true position and con- dition of the arc could be observed. Mr. C. L. Curties said that it was originally provided with crossed wires and screen. The President said that he had not used the electric arc for photo- micrography, but only the lime light. This was, however, not the ordinary lime light, but, as he had often described, was arranged so as to produce a small bright steady source of light. He- got this by using only about 1-inch pressure of gas and very hard lime, and in this way he obtained a comparatively steady light, although some of his negatives had been spoilt through some little irregularities in the lime or the pressure. One thing he liked the lime light for was with respect to the length of the exposure, as it was so much more easy to regulate a 5- or 10-second exposure than a 1/2-second one; but of course the electric arc had its advantages and was extremely clean. For this pur- pose he did not use the gas direct from the cylinders, because it was simply impossible to regulate it properly, but he worked with gas- holders which were filled from the cylinders. Mr. Beck asked what optical appliance, if any, was used between the light and the substage condenser. Mr. Barnard said he had used it both with and without a supple- mentary lens ; an ordinary plano-convex lens answered every purpose. The slide of typhoid bacilli had been taken with the lamp, using a current of 6 amperes, giving a light of from 700 to 800 candle-power. A screen of a saturated solution of bichromate of potash was used. The image was projected 7 ft. without an ocular, and the exposure was 6 seconds. The exposure could be varied by changing the pressure, and thus varying the size of the source of light. The President thought it was highly detrimental to the accuracy of a photomicrograph to work without the eye-piece. The greatest distance at which he had worked with an eye-piece was 6 ft. 6 in., and he thought it was hardly possible to exceed this with advantage. The President said he was sure that the Fellows who were present 2 t 2 602 PROCEEDINGS OF THE SOCIETY. had been greatly interested by the subject, and in the manner in which it had been brought before them. He had much pleasure in moving that a very hearty vote of thanks be given to Messrs. Barnard and Carver for their paper and exhibition. Carried unanimously. The President said that Mr. Yezey had kindly brought a number of slides for exhibition upon the screen. Mr. Yezey said that the series of slides (about 70) which were now to be shown on the screen, had been in his possession for some time, and had been painted by Mr. Underhill some years ago. It had been suggested that Fellows would like to see them, and so he had brought them up. The slides had been prepared principally to illustrate £ Pond Life.’ The description would be found on each slide, but in case any further information were required he had asked Mr. Rousselet to furnish it, as the subject had been his special study, The slides were then exhibited upon the screen. The President proposed the thanks of the Society to Mr. Yezey for bringing down this large number of beautiful slides for them to see, and to Mr. Kousselet for his explanatory remarks. The vote of thanks having been put to the meeting, was unanimously carried. _____ The following Instruments, Objects, &c., were exhibited : — Mr. Measures : — New Binocular Dissecting Microscope by Carl Zeiss. The President : — A Microscope which belonged to Sir David Brewster, lent for exhibition by Mrs. Brewster Fergusson. Mr. Geo. Hind : — Spider’s Web and Fly. Messrs. Barnard and Carver : — Lantern Slides illustrating their paper. Mr. Yezey : — 70 Hand-painted Lantern Slides of Pond Life. New Fellows. — The following were elected Ordinary Fellows : — Mr. G. H. Barker, Sr. Domingo de Orueta y Duarte, Mr. J. W. Flower, Mr. C. D. Soar, and Mr. W. T. Webster. 603 INDEX OF NEW BIOLOGICAL TERMS, OR OLD TERMS WITH NEW MEANINGS, RECORDED IN THIS VOLUME. a. ZOOLOGY. Accommodation, Baldwin, 193 Adelofcacta zoologica, Monticelli, 2 G Alloplasmatic, von Kolliker, 519 Arcki-holoblastic, Mitsukuri, 111 Archiplanoidea, Willey, 128 Archosome, Eisen, 271 Astrocoel, McMurrich, 117 Bipolarity (iu distribution), Ortmann, 21 Car oblast, Marchesini, 197 Centrodeutoplasm, Erlanger, 192 Centroplasm, Erlanger, 192 Critical stage, Beard, 109 Epigamy, Malaquin, 36 Ergastic, von Kolliker, 5 1 9 Germinal selection, Weismann, 107 Halmatogenesis, Eimer, 109 Hypotypic, Giard, 515 Kyeamechanie, Eimer, 109 Marennine, Carazzi, 28 Mechanomorphoses, Hertwig, 269 Meso-holoblastic, Mitsukuri, 111 Meta-holoblastic, Mitsukuri, 111 Meta-mesoblastic, Mitsukuri, 111 Metatrochophore, Hsecker, 206 Microsphere, Kostanecki and Siedlecki, 21 Myrmecoidie, Wasmann, 375 I Nectochseta, Hrecker, 206 ! Nucleochyme, Greenwood, 11 I Organic selection, Baldwin, 193 j Orthogenesis, Eimer, 108 I Orthoplasy, Baldwin, 193 Palseoneural canal, Todaro, 111 Palrcostome, Todaro, 111 Personal selection, Weismann, 107 Plasmocyte, Eisen, 271 Proto-holoblastic, Mitsukuri, 111 Protomacrosome, Greenwood, 11 Proto-mesoblastic, Mitsukuri, 111 Protromicrosome, Greenwood, 11 Protrochophore, Hsecker, 206 Reproductive selection, Pearson, 273 Schizogamy, Malaquin, 36 Syntrophy, Wasmann, 283 £. BOTANY. Ampliicarpogenous, Pampaloni, 518 Astigmatse, Yan Tieghem, 311 Ataxinomic (sens, nov.), de Candolle, 308 Bitegminatse, Van Tieghem, 313 Caroubinase, Effront, 101 Chloroplastin, Tswett, 131 Conid (sens, nov.), Dangeard, 561 Embryogenic bodies, Leger, 118 Embry ogenic spheres, Leger, 118 Embryonic spheres, Leger, 418 Geophilous, Rimbach, 215 Heterotype, Sargant, 213 Homotype, Sargant, 213 Hypocarpogenous, Pampaloni, 548 Individualism, Schneider, 411 Innucellatse, Van Tieghem, 216 Inovulatse, Van Tieghem, 216 Inseminate, Yan Tieghem, 313 Integminatse, Yan Tieghem, 216 Loliophyll, Etard, 401 Metaxin, Tswett, 134 Mutualism, Schneider, 411 Myxobotrysacee, Zukal, 154 Nutricism, Schneider, 411 Oidium (sens, nov.), Dangeard, 564 Ombrophoby, Hansgirg, 412 Parasymbiosis, Zopf, 228 Perovulatse, Yan Tieghem, 313 Plasmosynagy, Tswett, 131 Polioplasm, Tswett, 131 Primary sporocyte, Calkins, 302 Resinocyst, Schoennett, 402 Secondary sporocyte, Calkins, 302 Seminatse, Yan Tieghem, 313 Stigmatse, Van Tieghem, 314 Taxinomic (sens, nov.), de Candolle, 308 Tonotaxis, Beijerinck, 236 Transovulatre, Yan Tieghem, 312 Unitegminatse, Van Tieghem, 313 Zymase, Buchner, 559 INDEX. A. Abel, R., Plague Bacillus, 326 — Staining Coccidium oviforme, 175 Abnormalities in Echinoid Ova after Fer- tilisation, 539 Absorption and Emission of Water by Seeds, 54 Acanthobdella, Species of, 207 Accessory Parts, so-called, of the Skeleton, 364 Acetylene Gas in Photomicrography, 33S Achard, Ch., Presence of the Agglutinative Property in Blood-Plasma and other Body-juices, 329 Acid-loving Fungi, 149 Acquired Characters, Experiments on Supposed Inheritance of, 194 Inheritance of, in Camels, 523 Acrasiea;, Sappinia, new Genus of, 62 Actiniaria of Ternate, 298 Actinomycetic Form of Tubercle Bacillus, 329 Actinomycosis, 153 Actinotrocha, Structure of, 42, 537 Address to Her Majesty the Queen, 596 Reply to the, 597 Ade’otacta zoolog tea, 26 Adensamer, Th., New Dipterous Parasite, 530 Aderhold, R., Fusicladium, 152 — Sclerotinia, 420 — Yenturia and Fusicladium, 321 Adhesive Discs of Ercilla, 550 Adolphi, H , Variations in Spinal Nerves of Hyla, 522 JEcidia, Development, 60 jEcidiella, 320 JEcidium magellanicum, Mycele of, 321 Aeration of the Stem of Mikania, 657 Aerotropism of Roots, 221 iEtiology of Texas Fever, 46 Agar, Demonstrating Presence of, 177 — as Medium for Bacteriological Exami- nation of Water, 446 — Practical Method of Preparing, for Cul- tivation Purposes, 171 Agardh, A. G., ‘Analecta Algologica,’ 148 Agaricus ( Pleurotus ) ostreatus, Structure of, 322 Agassiz, A., Variations in Eucope, 132 Agglutination of Bacillus typhosus by Chemical Substances, 428 — Phenomenon and the Cholera Vibrio, 242 in Glanders, 242 of Typhoid Serum, 347 Agglutinative Action of Typhoid-Serum, 67 — Property, Presence of, in Blood-plasma and other Body-juices, 329 Ahlfvengren, F. E., Stem of Compositse, 401 Aida, T., Chaetognatha of Misaki, 386 — Growth of Ovum in Sagitta, 535 Aievole, E., Method for Demonstrating Blastomycetes in Neoplasms, 81 Air and Life, 274 — Method for Excluding, from Liquid Media for Anaerobic Cultures, 78 Airol, a new Antiseptic, 80 Albumen, Yolk and Shell, Proportions of, 110 Alcock, A., Natural Repellent Effect of “ Warning Colours,” 282 — New Species of Branchipus, 286 Alcohol, Action of, on Germination of Spores of Fungi, 418 Alcyonaria, New, 298, 540 Alexandrini, G., Unusual Case of Myiasis, 201 Algae. See Contents, xxiv — and Amoebae, Culture Medium, 343 — and Bacteria, Fixation of Atmospheric Nitrogen by, 54 — New Marine, 562 Aliciidse, 393 Alkaloids, Localisation of, in Cinchona, 544 Allescheriella, 565 Allium ursinum, Growth of, 410 Alpine Lakes, Fauna, 200 Alternation of Generations, 314 Ambergris, Bacteriology of, 428 Amhlycerseus luteus, 294 Amitotic Nuclear Division in Egg of Hedgehog, 17 Ammatoidea, 506 Amoeba, Cultivation of, 584 — Cultures, 312 606 INDEX. Amphibians, Monograph of European, 524 Amphioxus, Gastrula of, 357 — Maturation and Fertilisation in, 353 — New, 275 Ampliipoda, Notes on Distribution, 204 Amphipods of the Caspian, 285 Amphistomidse, Anatomy and Histology of, 38 Ampola, G., Bacillus denitrijicans agilis and Denitrification, 575 Ampullae in Millepora, 299 Amylomyces Bouxii and other Starch- Fer- ments, 232 Amylotrogus, a New Genus of Myxomy- cetes, 154 ‘Analecta Algologica,’ 148 Anatomical Specimens, Method of Prepar- ing, 586 Anatomy of Phanerogams. See Contents, xviii Anchors, Use of, in Synapta, 296 Andeer, J. J., Peritoneal Ostioles, 197 Anderson, A. P., Abnormal Formation of Resin-ducts, 403 Andrews, E. A., Plasmic Processes emitted from Serpula Eggs, 535 — G. F., Pseudopodia in Echinoderm Ova | and Embiyonic Cells, 211 — R. R., Development of Dental Enamel, 355 Augle, Proper, of Microtome Knife, 447 Annulata. See Contents, xiv — Marine, of the ‘ Caudan * Expedition, , 125 Antennaria, Fructification, 59 Antennophorus and Lasius, Relations of, | 376 Anther, Homology of, 305 Antherids of Taonia, 316 Antherozoids of Dictyota and Taonia, 563 j — - of Zamia, 554 Anthrax Cells in Blood, Staining, 84 Antidromy, 143 Antipatharia, Classification of, 297 Antiseptic, New, Airol, 80 Antitoxin, Diphtheria, New Method of obtaining, 248 Antitoxins, Function of, 559 Antivenomous and Antitoxic Qualities of ] the Bile of Serpents, and of other ani- mals, 570 Ants and Mites, 283, 377 — Natural History, 374 — Notes on, 375 — Remarkable Use of, 30 Apathy, S., New Knife-holder for Micro- tomes, 582 Apera Burnupi, Structure of, 370 Apertures of Objectives, 162 Aplococcus, 63 Apogamous Reproduction in Ferns, 223 Apparatus for Bacteriological Sampling of Well-waters, 579 I Appendages, Abdominal, 119 — of Arthropods, 279 Appendicular Organs, Symmetry, 306 Apterygota, Development, 281 Aquatic Insects of Illinois River, 279 — Plants, Morphology of, 405 Araclinida. See Contents, xiii Arboreal Algse, 562 Arcangeli, G., Leaves of Arum italicum , 217 — Spotted Leaves, 550 Arcliegone of Muscinese, 315 Armand, L., Changes produced by Myco- rbiza in the Cells of the Host-Plant, 546 Ariola, V., New Species of Bilharzia, 39 Arnold, J., New Method for Examination of Blood, 81 Arnold, W., Female Pro thallium of the Heterosporous Lycopodiacem, 55 Arnone, L., Simondsia paradoxa in Stomachs of Wild Boars, 127 Aroidese, Active Principles of, 400 Aromatic Principles in Leaves, 400 Arrow-Poisons, 135 Ar tlirop ada. See Contents, xix Arthropods, Tegumentary Innervation in. 118 Ascariasis, 536 Ascaris Germs, 126 Ascaris lumbricoides, Life-History, 126 — megalocepliala as a Cause of Death, 126 Ascomycetes, Behaviour of Nucleus in Development of Fructification of, 58 Asconematidse and Rossellidse, Revision of, 541 Asconidse, Natural Classification of, 43 Asellus, Development of, 35 Aspidogaster concliicola , 39 Assheton, R., Experiments on Growth of Blastoderm of Chick, 110 Assimilating Energy of Blue and Violet Rays of the Spectrum, 310 — Organs of jLeguminosse, 549 Assimilation of Ammoniacal Nitrogen and Nitric Nitrogen, 219 Assimilatory Inhibition, 311 Asteroidea of the North Atlantic, 296 Asteroids, Mediterranean, 540 Asthenosoma, New Species, 391 Astigmatse, 314 Astronomical Photography with Photo- micrographic Apparatus, 338 Atliroocystis, 317 Attachment, Organs of, in Botrytis, 151 . Attraction-Spheres in Spermatogenesis, 192 Aubertin, G., Manipulation of Celloidin Sections, 174 Auclair, J., Human Tuberculosis in the Pigeon, 573 Auditory Vesicle in Vertebrates, Develop- ment, 191 Auranthicese, Spines, 50 INDEX, 607 Auricular la auriculx-Judx , G1 Automatic Gas-Stop for Extinguishing the Burner of Incubators, 337 Autotomy and Regeneration in Earth- worms, 287 — in Phasmidsa, 528 Auxospores of Diatoms, 62, 233 Axenfeld, Tli., Bacteria of Conjunctivitis, 328 Axis, Elongation of, 139 — Symmetry of, 50 Azores, Freshwater Fauna, 26 B. Bab£s, V., Actinomycetic Form of Tuber- cle Bacillus, 329 — AEtiology of Foot and Mouth Disease, 575 Bacillus of Friedlaender in Tonsillitis and Pharyngitis, 243 — of Seborrhoea, Cultivating the, 248 Bacillus capsulalus aerogenes, 328 — denitrificans agilis . and Denitrification, 575 — Oleze and Cheetophoma oleacina, 323 — pyocyaneus , Pigmentary Functions, 67 — radicicola , Adaptability of, to Foreign Nutritive Media, 158 — tuberculosis , Biological Status of, 242 Bacteria and Algae, Fixation of Atmo- spheric Nitrogen by, 54 — of Root-Tubercles, 53 — Pathogenic, in Buried Bodies, 66 Bacterial Disease of Cotton, 425 of Plants, 237 of the Squash-Bug, 237 Bactericidal Action of Tannin, 239 Bacteriosis of Celery, 237 — of Hemp, 157 Bacterium coli anindolicum and Bacterium coli anatrogenes , 243 Bag-Shelter of Larvae of Australian Moths, 28 Bailbaclie, G., Influence of the Stock on the Graft, 219 Bailey, L. H., Flower of Canna, 49 Baker, C., 348 — F. C., Pulsations of the Heart in Molluscs, 276 Balanophoracese, Embryology, 51 Balazs, J., Structure of Pollen-Grains, 404 Baldness, Microbial Origin, 210 Baldrati, J., Scales of Bulbs of Allium, 307 Baldwin, J. Mark, Organic Selection, 193 Balicka-Iwanowska, G., Morphology of Thelygonum Cynocrambe, 407 Ballowitz, E., Demonstrating the Electric Organs of the Ray, 592 Bambeke, Ch. van, Cell-Boundaries, 270 — Membranaceous Mycele, 58 Bambeke, Ch. van, Oogenesis in Pholcus, 283 Bange, R., Diagnosis of Smegma and Tubercle Bacilli, 347 Barbagailo, P., Amoeba Cultures, 342 Barbone Disease of Cattle and Pigs, 574 Barnard, J. E., On the Application of the Electric Arc to Photomicrograph v, 600, 601 Barnes, C. R., Genera and Species of Mosses, 224 Barth, F., Structure of Trigoniaceae and Chailletiacese, 49 Bataillon, — ., New Type of Tuberculosis, 571 — Saprophytic Form of Human and Avian Tuberculosis, 572 Baur, R. W., Proportions of Yolk, Albu- men, and Shell, 110 Bauscli and Lomb, Reversible Mailing Cases, 253 Bavay, A., Remarkable Pseudhelminth, 41 Bdella, Resume of Anatomy of, 97 Beard, J., Problems of Vertebrate Em- bryology, 109 Beauregard, H., Bacteriology of Ambergris, 428 Beck, Conrad, 599, 601 [ — R. and J., 318 j — Hand Magnifiers, 596 i — New form of Centrifuge, 596 l — New Microscopes, 596 Beddard, F. E., Oligochaeta of North America, 125 Bedriaga, J. von, Monograph of European Amphibians, 524 I Bee, Brain of, 29, 80 Beecher, C. E., Classification of Trilobites, : 205 Bees Intoxicated with Honey, 120 | Beet Parasites, 151 , Beetles, Metamorphoses, 29 ; — Parasitic, 31 j Behrens, J., Regeneration of Selaginella, 560 Beijerinck, W., Gynips calicis, 119 — Emulsion and Sediment Figures pro- duced by Motile Bacteria, 236 — Peculiarity of Soluble Starch, 135 I Bell, A. S., Influence of a Previous Sire, 514 — F. J., 179, 181 Belli, S., Endoderm and Pericycle iu Trifolium, 136 Beneden, E. van. Historical Note as to Polar Bodies, 516 Benham, W. B., Earthworms from Celebes, 37 j — New Species of Perichaeta, 386 Bennett, A. W., A Contribution to the Freshwater Algae of the South of Eng- ! land, 467, 511, 597 608 INDEX. Bensaude, R., Presence of the Agglutina- tive Property in the Blood-Plasma and other Body-Juices, 329 Bensley, R. R., Two Forms of Distomum cygnoides, 293 Berg, A. Hijmans van den, Staining Go- nococcus by Gram’s Method, 84 Bergh, R., The Genus Doriopsilla, 117 Beri-Beri, iEtiology of, 576 Berlese, A., Italian Coccidae of Fruit Trees, 121 Bernard, Felix, Embryonic Shell of Bi- valves, 259 — Hinge-Teeth in Lamellibranchs, 370 — Lamellibranch with an Internal Shell, 528 — H. M., Galeodida?, 380 — Interrelationships of Madreporidae, 541 Berthold, G., Conjugation of Swarm-spores, 418 Bescherelle, E., Ochrobryum, 315 Bessey, C. E., Compound Ovaries, 50 — Divergence of Monocotyledons and Di- cotyledons, 55 Bethe, A., Methylen-Blue Methods, 82 Bettendorf, H., Musculature and Sensory Cells of Trematodes, 390 Betulaceae, Anatomy, 137 Bey, Zia, Pigmentary Functions of Bacil- lus pyocyaneus, 67 Bichromates and the Nucleus, 452 Biffen, R. H., Latex and its Function, 401 Biflagellata, 394 Bilharzia, New Species, 39 Billings, J. S., Influence of certain Yeasts in Destroying the Vitality of Typhoid and Colon Bacilli, 243 Binaghi, R., Streptococcus capsulatus, 577 Biology, Problems of, 198 Bionomics of Australian Animals, 198 Bipolarity in Distribution of Marine Animals, 24 Bisogni, C., Lingual Glands of Vipers, 363 Bitegminatae, 313 Bitter, G., Leaves of Ranunculaceae and Umbelliferae, 217 Black-Rot of Vine, 230 Blackman, V. H., Coccosphere3 and Rliab- dospheres, 318 Blanchard, R., Dermatobia noxialis, 33 Blandford, W. F. H., Castes in Termites, 370 Blastoderm, Margin in Salmonidae, 21 — of Chick, Experiments on Growth, 110 Blastomycetes in Hypertrophied Tonsils, 568 — in Neoplasms, Method for Demon- strating, 81 — Morphology of, 422 — Pathogenic Action of, 233 — Protection of the Organism against, 154 Blastopore of Chclonia, 110 Blaxall, F. R., Action of Glycerin on Growth of Bacteria, 64 — Cultivation Medium for Ringworm Fungi, 79 — Ringworm Fungi, 61 Blood-Corpuscles, Red, 197 Films, Rapid Method of Fixing and Staining, 175 — -formation in Lamprey, 355 — New Method for Examination, 81 — of Lamprey, 1 1 2 Vascular System and Excretory Organs of Tetrastemma grxcense , 127 Vessels in Epithelium, 360 Blowpipe, Method of Extemporising, for making Sedimentation Tubes, 251 Body-Cavities and Connective-Tissues of Nemerteans, 209 and Mesoderm, 270 Bogheads, Bacteriaceae of, 326 Bohmig, L., Excretory Organs and Blood- Vascular System of Tetrastemma grx- cense, 127 Bohn, Georges, Respiration of the Crab, 533 Boirivaut, — ., Replacement of the Primary Root by a Secondary Root, 407 Bokorny, Th., Food-Material of Algae and Fungi, 562 — Organic Nourishment of Green Plants, 218 Bolley, H. L., Apparatus for Bacterio- logical Sampling of Well-Waters, 579 Bolsius, H., Unpaired Gland of Haemen- taria, 125 Bombyces, Larvae of the Higher, 119 Bonnet, R., Prochorion of the Dog, 190 Bonnier, J., Crustacea of the ‘ Caudan * Expedition, 124 Bonniere, K., Tunicata of Norwegian North-Atlantic Expedition, 115 Book- Worm, Californian, 376 Bordage, Edmond, Autotomy in Phasmidae, 528 — Tetrameric Regeneration of the Tarsus in Phasmidao, 374 Bordas, L., Classification of Insects, 281 — Nervous System of Mecopodinae, 33 — Sympathetic System of Orthoptera, 378 Borgert, A., Distribution of Doliolum, 25 Borneo and Moluccas, Explorations in, 113 Borzi, A., Cross-Fertilisation nnd Self- Fertilisation, 141 — Mechanism of the Phenomena of Sen- sitiveness, 220 Bose, — ., Mechanism of Immunity im- parted by Anti-coagulating Substances, 239 Bosse, A. Weber van, Pseudocodium, a new Genu3 of Siphoneae, 57 — Sarcomenia, 56 Bossebceuf Petiole of Quercus, 51 INDEX. 609 Botezat, E., Nerve-Endings in Tactile Hairs of Mammals, 362 Bott, A., Budding Cysticercus from Mole, 536 Bottle for Immersion Oil and Canada Balsam, 580 Botulism, Epidemic of, 327 Boubier, A. M., Anatomy of Betulaceso, 137 Bouilhac, R, Fixation of Atmospheric Nitrogen by Algse and Bacteria, 54 Boulanger, E., Development of Volutella, 567 — E., New Conidial Form of Gheeto- mium, 321 Bouvier, E. L., Structure and Affinities of Pleurotomaria, 277 — The Genus Sympagurus, 383 Boveri, Th., Conditions of Cell Division, 519 Boyce, R.. Green Leucocytosis in Oysters, 527 Brachet, A., Liver and Pancreas in Ammo- ccetes, 517 Brachionus Balceri and its Varieties, 288 Brady, G. S., New Ostracods, 384 Brain and Optic Ganglion of Leptodora hyalina , 205 — of Bee, 29, 80 Optic Lobes, 280 — of Fishes, Investigation of, 174 Braithwaite’s British Moss-Flora, 224 Branchipus, New Species, 286 Brandes, G., Alleged Modification of Bird’s Stomach, 194 — Life-History of Ascaris lumbricoides, 126 — Parasitic Beetles, 31 Brandis, D., Structure of Dipterocarpacese, 137 Brandt, A., Hypertrichosis, 195 — Viragines, 195 — K., Fauna of Kaiser Wilhelm Cana!, 116 Branner, J. C., Bacteria and the Decompo- sition of Rocks, 325 Brannon, M. A., Structure and Develop- ment of Grinnellia, 225 Brasilin, 591 Brauer, A., Development of Gymnophiona, 357 Brauns, R., Covered Rectangular Motions for Stages, 439 Braus, S., Preparation and Horizontal Bino- cular Microscope, 431 Bray, T. J , Photomicrography, 338 Breitfuss, L., Calcareous Sponges from Ternate, 44 — New Calcareous Sponge, 44 Bremer, L., Staining Reaction of Diabetic Blood, 458 Bressadola, J., New Genera of Fungi, 58 Brewster, E. T., Measure of Variability, 522 Brewster, Sir David, Microscope, 600 Briquet, J., Cross-Fertilisation and Self- Fertilisation, 141 — Secreting Pockets of Myoporacese, 48 Brizi, Ugo, Bacteriosis of Celery, 237 — Preparing and Staining Celery for De- monstrating Bacteria, 249 — Rhynchostegium, 146 Brolemann, H. W., Algerian Iulkhe, 531 — A Mysterious Myriopod, 379 Bromeliacem, Structure of, 407 Bronzing of Copper, 593 Brood-Care in Holothurians, 391 Brook’s Collection from West Coast of Scotland, 116 Brown, A., Fragmentation in Lineus yes- serensis, 208 — A. J., Fermentative Power, 222 Browne, E. T., Tulmlaria crocea in Ply- mouth Sound, 540 Brownian Movement, 454 Browning Iron or Steel, 594 Bruhn-Fahrseus, E. G. M., Number of White Corpuscles, 524 Brundin, A. Z., New Alcyonaria, 540 Bryhn, N., Distribution of Spores in the- Splachnacese, 224 Bryozoa. See Contents, xi Buchner, E., Advances in the Chemistry of Fermentation, 559 — Alcoholic Fermentation without Yeast,. 222, 414 Bucholtz, F., Development of Tuberaccfo, 419 — Meliola, 567 Budding in Ecteinascidia, 366 Buds, Metamorphosed, of Lilium bulbi- ferum , 406 Bujwid, O., Concentration of Therapeutic- Sera by Freezing, 593 Bulbils of Characese, 147 Bullard, C., Correlated Variation, 359 Bullot, G., Growth and Curvature of Pliy- comyces, 312 Bumpus, H. C., Study in Variation, 193 Bunker, F. S., Sensory Organs of the Late- ral line, 196 Burchardt, E., Bichromates and the Nu- cleus, 452 Burgerstein, A., Transpiration of Tropical Plants, 312 — Wood of Pomem and Amygdalcje, 546 Burnap, C. E., Calostoma, 322 Burnett, K. C., Influence of Light on Dorsi- ventral Organs, 311 Burrage, J. H., Adhesive Discs of Ercilla, 550 Burri, R., Adaptability of Bacillus radt- cicola to Foreign Nutritive Media, 158 — Denitrifying Bacteria and the Loss of Nitrogen caused by them, 236 Burrill, J. H., Fertilisation of Spring Flowers, 309 610 INDEX. Burt, E. A., Lengthening of the Recep- tacle of the Phalloidese, 568 — Receptacle of Glathrus, 123 Buscalioni, L., Encapsuling of Starch- grains, 135 — Formation of the Endosperm in Leu- cojum, 213 — New Method of Staining Tubercle Bacilli, 175 — Sacchciromyces gultulatus Rob., 60 Butler, A. G., Seasonal Dimorphism in African Butterflies, 280 Butscliinsky, P., Protozoa of Salt Lakes, 300 — Segmentation of Nebalia Ovum, 381 Biitschli, O., Artificial Starch, 48 Butyric Acid, Bacillus forming, from Glycerol, 241 Bye-Law, New, 350 Bye-Laws, Alteration of, 181, 254 C. Oajal, S. Ramon y, Phagocytosis by Blood- plates, 23 — Protoplasm of Nerve-Cells, 22 Calandruccio, S., Development of Eels, 356 — Further Researches on Metamorphosis of Mursenoids, 356 Calcareous Algae, 317 — Deposits in Stichopus, Changes in, 391 Calcium Oxalate, Function of, 219 Calculating Machine, New, 1, 88 Calkins, G. N., Chromatin-Reduction and Tetrad-Formation in Pteridophyta, 302 Call, R. Ellsworth, New Discoveries in the Mammoth Cave, 276 Calmette, A., Non-Microbic Toxins, 159 Calostoma, 322 Camerano, L., New Classification of Gor- diidae, 387 Campbell, D. H., Development of Geo- thallus, 146 — Jas., Wasps, 29 Campeuhausen, B. v., Hydroids of Ternate, 298 Campoden, Development, 373 Camptothrix, 423 Cancer Cells, Evolution of Mucus in, 326 Candolle, A. de, Structure of Piperacese, 402 Candolle, C. de, Latent Life of Seeds, 220 — Vegetable Teratology, 308 Canna, Flower of, 49 Cantacuzene, J., Phagocytic Organs in Marine Annelids, 385 Canu, E., Crustacea of the ‘ Caudan ’ Expe- dition, 124 Capaldi, A., Egg-Yolk as an Adjunct to Nutritive Media, 78 Car, L., Movements of Freshwater Gas- teropods, 525 [ Carazzi, D., Green Oysters, 27 Carbonic Acid, Influence of, on the Growth of, and Toxin-Formation by Diphtheria Bacilli, 241 Carcinus Mxnas , Changes in the Carapace, 34 Carlton, E. P., Brain and Optic Ganglion of Leptodora liyalina, 205 Carnoy, J. B., Germinal Vesicle and Polar Bodies in Batrachia, 353 Caroubinase, A New Hydrolytic Enzyme, 401 | Carpiaux, E., Assimilation of Ammoniacal Nitrogen and Nitric Nitrogen, 219 i Carpotropic and Gamotropic Movements, 412 Cartilage, Structure and Development of 1 in Cyclostomes, 362 Carver, T. A. B., On the Application of the Electric Arc to Photomicrography, 600, 601 Casagrandi, O., Amoeba Cultures, 312 I — • Morphology of Blastomycetes, 422 | Castes in Termites, 370 ! Castracane, F., Rhizosolenia, 323 I — Sporulation of Diatoms, 63 j Catalogue of Slides, 595 I Catasetum, Irritability of, 144 J Cathcart Microtome, Improved, 589 ; Catois, — ., Investigation of Brain of Fishes, 174 Cattaneo, G., Inheritance of Acquired Characters in Camels, 523 Catterina, G., Bacteria in Ice, 326 | Cattle Malaria, 330 ; Caullerv, M., Asymmetry of Spirorbis, 206 j — Compound Larva of a Synascidian, 367 j — Crustacea of the ‘ Caudan ’ Expedition, 134 — New Epicarid Parasite, 204 — Pycnogonida of the ‘ Caudan ’ Expedi- tion, 123 — Tunicata of the ‘ Caudan * Expedition, 115 Cave Isopod, New, 285 Celakovsky, L. J., Development of the Flower, 403 Cell-Boundaries, 270 — -Bridges in Unstriped Muscles, 361 I Division, Conditions of, 519 Influence of Light on, 213 Hypertrophies produced by Galls, 302 — in Development and Inheritance/ 1 The, ! 111 ] Membrane, 399 j of Lichens, 231 j — Structure and Physiology, 134, 299 -of Phanerogams. See Contents, xviii ! — Text-Book on the, 196 Wall, Influence of the Nucleus on tho Formation of, 544 I Celli, A., Cattle Malaria, 330 INDEX. 611 Celloidin, Decoloration of, in Orcein Pre- parations, 176 — Sections, Manipulation, 171 — Serial Sections, Technique of, 447 Cells and Energids, 519 Celtidia, 320 Cement for Porcelain, 85 Cements and Pastes for General Purposes, 593 Centrifuge, New form of, 596 Centrosome and Yolk-Lobe of Fulgur, 117 — Artifact in Nerve-Cells, 196 Centrosomes and Attraction-Spheres in Leucocytes of Newt, 112 — in Ganglion and Cartilage Cells, 519 — in Spermatocytes of Lepidoptera, 530 — Relation of to Cytoplasm, 21 — Staining, 176 Cephaleuros, New, 57 Cephalodiscus, Structure of, 538 Cephalopod, Gigantic, 116 Cephalopoda. See Contents, xi — Indian, 369 Ceratostoma and Teichospora, Develop- ment, 151 Cerebral Cortex, Structure of, and Func- tion of Nerve-Cell Processes, 196 — Neurones, Plasticity of, 272 Cerium and Zirconium Groups, Influence of, on Growth of Bacteria, 157 Cestracion, Early Development of, 516 Chretognatha of Misaki, 386 Chretomium, New Conidial Form, 321 Chxtophoma oleacina and Bacillus Olex, Association of, 323 Chailletiacese and Trigoniacese, Structure of, 49 Chalazogamy, Significance of, 52 Chamberlain, C. J., Embryogeny and Fer- tilisation of Lilium, 552 — Embrogeny of Salix, 309 Chances of Death, 272 Chapman, F., Foraminifera of the Gault at Folkestone, 598 Characeae. See Contents, xxiv Charrin, A., Plurality of Morbific Products from a Single Pathogenic Microbe, 325 Chatin, A., Symmetry of Appendicular Organs, 306 — of the Axis, 50 — J., Alleged Nematode Parasites of Truffles, 289 — Epidermic Nuclei of Anguillulidae, 387 — Clasmatocytes in Lamellibranchs, 278 Chauliaguet, J., Active Principles of the Aroideae, 400 Cheddar Cheese, Rise and Fall of Bacteria in, 571 Cheese-Ripening, Microbic Agents of, 325 Cheirostrobus, a new Type of Fossil Cone, 314 Chelonia, Blastopore, 110 Chemical and Physical Agents, Effect of certain, on Staining Sporous and Aspor- ous Bacteria, 250 — Changes in Phanerogams. ^See Con- tents, xxiii — Reagents and Light, Influence on Ger- mination, 310 Behaviour of Bacteria to, 324 Chemistry! of Fermentation, Advances in, 559 Chicken-Cholera in Australia, 240 Chlorogonium, 317 Chlorophyll Function, and the Relation of the Growth of Foliage-Leaves, 52 — Spectrum, 48 — Temporary Suspension of the Action of, 220 Chmilewskij, W., Structure and Multi- plication of Pyrenoids in Algae, 316 Chodat, R., Effect of Low Temperatures on Mucor Muceclo, 228 — Encrusting and Perforating Algae, 417 — Evolution of Green Algae, 226 — Oscillatoria rubescens, 156 — Pelagic Flora of the Swiss Lakes, 568 — Snow-Flora of Mont Blanc, 149 Chorisis and Cohesion of Foliar Leaves, 547 Christmas, J. de, Cultivating Gonococcus, 443 — Gonotoxin, 575 Chromatin-reduction and Tetrad-formation in Pteridophyta, 302 Chromatin-reduction in Oogenesis of As- caris, 536 Chromogenic Microbes from the Mouth, 427 Chrysobalaneae, Anatomy of, 304 Chytridium simulant, 58 Cissus gongylodes, Anatomy, 305 Cladocera and Copepoda, Freshwater, of Portugal, 36 — of Manitoba, 286 — Revision of, 124 Cladotlirix odorifera, 238 Clarkson, Arthur, ‘Text-Book of Histo- logy,’ 69 Clasmatocytes in Lamellibranchs, 278 Classification, Importance of Anatomical Characters in, 49 — New, of Flowering Plants, 313 Clathrus, Receptacle of, 153 Claudius, Simple Method for Contrast- Staining Micro-Organisms, 344 Clavogaster, 58 Cleavage- Centrosomes, Origin of, 515 Cleistogamy in Umbelliferae, 408 Clements, F., Origin of Lichens, 322 Clifford, J. B., Rheotropism and Thermo- tropism in a Plasmode, 413 Clonothrix, 63 Clos, D., Homology of the Anther, 305 Closing Fishing Net, 582 INDEX. -Coagulation, Spontaneous, of Milk, 242 Cobb, N. A., Method of Using the Micro- scope, 433 •Coccidse, Check- List of, 281 — Italian, of Fruit Trees, 121 Coccidia, Experimental Study of, 395 — Life-Cycle of, 301 — Life-History of, 397 — Monograph on, 212 — of Myriopods, 300 Coccidium oviforme. Staining, 175 Coccospheres and Rhabdospheres, 318 Cochon, J., Life History of Dendroctonus micans, 120 Cockerell, T. D. A., Check-List of Coc- oidae, 281 Ccelentera. See Contents, xvii — of the ‘ Caudan’ Expedition, 131 •Coggi, A., Viviparity of an Ephemcrid, 374 Cohesion and Chorisis of Foliar Leaves, 547 Colchicum autumnale, Growth of, 410 Coleosporium Pini , 152 Coli Bacteria, Bacteriological Examina- tion of Water for, 66 Collcutt, M. C., Structure of Hydractinia, 392 Collecting Objects. See Contents, xxxi Collett, O,, Nematode Parasite from Mantis, 388 Collin, Anton, Rotatoria from East Africa, 208 Gollinge, W. E., Structure of, Apera Bur- nupi, 370 Collodine, 593 Coloration, Nocturnal Protective, 113, 274 — of Scales in Beetles, 120 Colour and Sex of Flowers, Influence of Nutrition on, 142 — of Flowers, Influence of Soil on, 305 Screens and Light-Filters, 438 Use of, for Photomicrography, 70 — - Variation in Vanessae, 28 Coloured Illumination, 336 Colouring-Matter of the Aril of Celastrus, 48 of the Tomato, 214 •Colours of Lepidoptera, 282 Colucei, V., Simondsia parctdoxa in Sto- machs of Wild Boars, 127 Comber, Thomas, The Limits of Species in the Diatomacese, 455, 597 Combs, R., Micrococcus cyanogenus, 161 Comparative Anatomy of Vertebrates, 364 Compound Larva of a Synascidian, 367 •Compressorium, 581 — Heating Arrangement for, 581 Condensing Lens, Cheap, 582 Conjugation of Swarmspore3, 41S — of two Zygotes, 317 Conjunctivitis, Bacteria of, 328 Conn, H. W., ‘ Story of Germ Life,’ 577 Connections, Protoplasmic, between Blas- tomeres, 270 Connective Tissues and Body-Cavities of Nemerteans, 209 Continuity of Protoplasm, Methods for Demonstrating, 343 Contractile Roots, 551 — — of Arum, 307 Contrast Staining in Bacteriological Work, M:cro-Organisms, Simple Method for, 344 Contribution to the Freshwater Algae of the South of England, 467 Copeland, E. P., Influence of Light and Temperature on Turgor, 54 Copeman, S. M., Action of Glycerin on ! Growth of Bacteria, 64 Copepoda and Cladocera, Freshwater, of Portugal, 36 Copepods, Free Swimming, from West | Coast of Ireland, 205 I — Freshwater, of Germany, 534 — of Moscow, 533 — Systematic Notes on, 383 i Copulation, Pseudo- Larval, of some Sar- coptidae, 123 j Coral Reef at Funafuti', 131 ( Corallinaceae, 225 Cori, C. J., Closing Fishing Net, 582 j — Diamond for Cutting Glass Discs, 582 — Mud Collector, 584 Cork-Growths, 304 Cormack, B. G., Polystelic Roots of Palms, 546 Cornu, M., Fruit of Argania Sideroxylon, 548 — Stem of Cuscuta, 401 ! Correlated Variation, 359 ! Correns, C., Movements of Oscillatoriaceae, 324 ! — Parasitic Fungus, 230 , Cossus ligniperda , Mandibular Glands, 119 Cotton, F. J., Excretion of Bacteria by the Animal Body, 426 ■ Coulter, J. M., Embryogeuy and Fertili- sation in Lilium, 552 — Embryogeny of Conifers, 309 j — Significance of Chalazogamy, 52 I Council, Report of, for 1896, 90 I Counting Plate Colonies, Rapid Method ! for, 346 : Coupin, H., Absorption and Emission of Water by Seeds, 5 4 , — Micropyle of the Seed in Leguminosae, 404 — Mucilage excreted by Seeds, 558 | Couvreur, E., Reserve-Stores of Seeds, 135 Crabs, Notes on, 203 i Craig, C. F., Staining Diphtheria Bacilli, 345 I Craspedota, 258 ' Crest of Seeds, 405 INDEX. 613 Cribraria and Physarum, G2 Critical Period in Development of Horse, 515 Cross-Fertilisation and Self-Fertilisation, 141 Pollination and Self-Pollination, 403 Crustacea. See Contents, xiv — of the “ Caudan ” Expedition, 124 — Limnetic, of Green Lake, 534 Crystal Formation in Culture Media, 343 Crystalline Lens, Isolation of Elements, 173 Cryptogamia. See Contents, xxiv Cryptophallus, 320 Ctenoplana, 128, 295 Cuenot, L., Double Use of the Name Diplocystis, 396 — Gregarines of the Cricket, 396 — Means of Defence in Insects, 200 — Nuclear Degeneration and Renewal, 363 Culicidse, European, Revision of, 529 Cullen, T. S., Rapid Method of making Permanent Specimens from Frozen Sec- tions by Use of Formalin, 344 Cultivating Gonococcus, Egg-yolk Agar for, 586 Cultivation of Amoeba, 584 — of Bacteria, Silk-Glue as a Medium for, 584 — Medium for Ringworm Fungi, 79 Culture Media, Preparation of, and their Sterilisation, 341 Culture Processes. See Contents, xxxi Cummins, H. A., Function of Antitoxins, 559 Cunningham, J. T., Ovary and Ovarian Ova in Marine Fishes, 353 — Recapitulation, 351 — K. M., Brownian Movement, 454 Currents of High Frequency, Action of, on the Virulence of Streptococci, 328 — of Pigments and Saline Solutions in Dicotyledons, 556 Curties, C. L., 600, 601 — New Microtome, 86 ., Nose-piece, 180 •Curtius, T., Volatile Reducing Substance in Green Cells, 303 • Curvature of Roots, 413 Cutting Glass Discs, Diamond for, 582 — and Mounting Sections of Cereal Grains, 250 Cutting Objects. See Contents, xxxii Cyanopliycem and Bacteria, Structure of, 156, 423 — New Genera, 63, 423 — Structure, 235 Cycas, Fertilisation of, 140 •Cyclamen, Evolution, 307 Cyclops, North American Species, 533 Cyclostoma, Notes on, 118 -Cyclostomella, 320 Cynips Cctlicis, 119 | Cypridina II il gender fi, Phosphorescence of, 384 j Cysticerci of Bothriocephalus latus, 40 Cysticercoids of Freshwater Crustacea, 536 Cysticercus, Budding, from Mole, 536 ! — of Taenia liopliallus, 3S9 ! — venusta , 389 Cytidium, A new Genus of Myxomycetes, j 155 j Cytology, Vegetable, 47 Cytoplasm, Relation of Centrosomes to, 21 Cytoryctes vaccinse , Fixation and Staining, 447 Czapek, F., Leptnme of Angiosperms, 303 Czenvinski, K., Notes on Termites, 282 D. Daday, E. von, Freshwater Nematodes of Hungary, 290 Dahlgren, W., Centrosome Artifact in Nerve-Cells. 196 — Giant Ganglion-Cells in Spinal Cord of Flat-Fishes, 196 D’Ailly, Adolf, Terrestrial and Freshwater Molluscs of Kameroon, 526 Dallinger, W. H., Biflagellata, 394 Dangeard, P. A., Changes produced by My- corhiza in the Cells of the Host-Plant, 547 — Chytridium simulans, 58 — Classification of the Spores of Funo-i. 564 — Parasitic Fungi, 60 — Red Pigment in Mucor, 566 — Reproduction of Sphaerotheca Castagnei, 59 j — Sappinia, A new Genus of Acrasieae, 62 — Sexual Reproduction in the Ascomy- cetes, 566 Daniel, L., New Mode of Grafting, 556 — Reciprocal Influence of Stock and Graft on one another, 310 Darbi shire", O. V., Pertusarieae, 322 — Roccellese, 231 | ‘ Darwin, and after Darwin,’ 512 — F., Ascent of Water in Trees, 143 Darwinism, Present Position of, 358 Dassonville, C., Effect of Mineral Salts on Development, 411 Davenport, C. B., Correlated Variation, 359 — Experimental Morphology, 198 — Role of Water in Growth, 556 1 David, E., Anatomy of Lycopodium, 415 I — T. W. E., Diatomaceous Earth, 155 Davis, B. M., Procarp and Cystocarp of Ptilota, 148 — J. J., Parasitic Fungi, 150 Day, D. F., Parthenogenesis in Thalictrum, i 52 ! — R. N., Position of Dorsiveutral Organs, i 403 614 INDEX. Day, R. N., Position of Leaves, 50 — T. C., Germination of Barley, 219 Dead Bacteria, Employment of, in Serum Diagnosis of Typhoid and Malta Fever, 250 Dead-Black Surface for Brass, 253 Dean, Bashford, Larval Development of Amia calva , 20 Debski, B., Division of Nucleus in Ohara. 416 Decalcifying and Desilicating Sponges, 588 Decapod Crustacea, Functions of certain Diagnostic characters, 123 Decapods and Stomatopods, Malayan, 204 — Eyes of, 33 Decomposition of Rocks, Bacteria and, 325 Defence, Means of, in Insects, 200 Defendorf, A. R., Relation of Yeasts to Malignant Tumours, 321 Degagny, C., Respiratory Function of the Nucleus, 47 Degradation and Transformation of Sexual Organs, 141 De Guerne, J., Freshwater Copepoda and Cladocera of Portugal, 36 Deherain, P. P., Reduction of Nitrates, 414 Delacroix, — Parasitic Fungi, 420 Delarde, A., Non-Microbic Toxins, 159 Delepine, A. S., Technique of Serum Diagnosis, 218 Delepine, S., Agglutinative Action of Ty- phoid-Serum, 67 Delezenne, — Mechanism of Immunity imparted by Anti-coagulating Sub- stances, 239 Demoor, J., Plasticity of Cerebral Neu- rones, 272 Dendromena, 562 Dendy, A., New Zealand Hoiothurians, 297 — Non-Calcareous Sponges of Victoria, 541 — Non - Calcareous Sponges from Port Phillip Heads, 132 Denitrification, and Bacillus denitrificans agilis, 575 Denitrifying Bacteria, and the Loss of Nitrogen caused by them, 236 Dental Enamel, Development and Struc- ture, 183, 261, 355 Dentition of Manatee, 18 Dendroctonus micans, Life History, 120 Dermatobia noxialis, 33 Desilicating and Decalcifying Sponges, 588 Desmids, Index of, 227 Devell, D. V., Sensitiveness of Frogs to Infection with Plague, 570 Development and Structure of Dental ' Enamel, 261 Deviations in the Flower of Polygonum, 215 Diabetic Blood, Staining Reaction of, 451 Diamare, V., Entozoic Tuberculous New Formations, 293 — Gonads of Amabilia, 389 Diamond for Cutting Glass Discs, 582 Diapensacese, Structure, 305 Diastase, Action of Light on, 222 on Reserve-Cellulose in Germina- tion, 414 | — Formation of, 312 Diatomaceae, The Limits of Species in the, 455 : Diatomaceous Earth, 155 | Diatoms, Auxospores of, 62, 233 — Growth of, 62 — Marine, Reproduction of, 155 — Movements of, 569 — Structure, Division, and Movements, 234 Dicotyledons and Monocotyledons, Diverg- ence of, 55 | Dictyographa, 232 Didymochlamys, 565 Dietel, P., Characters of Ustilaginem, 229 Differential Staining of Tubercle and Smegma Bacilli, 450 Differentiating Bacillus typhosus from Bac- terium coli commune , Medium for, 442 ’ Digestive Organs of Hemiptera, Bacteria | normal to, 327 Dimorphic Branches of Castilloa, 307 Dimorphism and Variation, Sexual, 23 — Seasonal, in African Butterflies, 280 Dineur, — ., Epidemic of Botulism, 327 Diphtheria Bacilli, Cultivation on Non- Albuminous Media, 171 : Growth of, on Different Media, 585 - — Differentiation of, from Pseudo-Diph- theria Bacilli, 240 — or Diptheroid Bacilli in Empyema Pus, 68 j Diplocystis, Double Use of the Name, 396 ! Diplopoda, Bohemian, 531 | — Investigations on, 202 ; — Morphology and Classification of, 379 — New Indo- and Austro-M'alayan, 531 — Ovum, 202 — Rheno-Prussian, 530 J Diploposthe hevis, 38S Dipterocarpaceae, Structure, 137 j Disinfection of Books, 178 | Dissecting Microscope, New Binocular, 599 i Dissemination of the Spores in Sphagnum, I 225 Distoma Opisthobrias, 39 Distomum cygnoides, Two Forms of, 293 — felinum, 39 Distribution of Marine Organisms, 276 — of Spores in Splaehnaceae, 224 — of Terrestrial and Freshwater Verte- brates in Victoria, 524 Ditella, 564 Dobrzyniecki, A. R. v., Leptothrix placoides, 238 INDEX. 615 Dobrzyniecki, A. R. v., Two Chromogenic Microbes from the Mouth, 427 Doderlein, L., Lithonina, 299 Doliolum, Distribution of, 25 Dollfus, Adrien, New Subterranean Iso- pods, 381 Dollken, A., Imbedding Tissues without Hardening in Alcohol, 448 Domatia, 405 Doriopsilla, Genus, 117 D’Orleans, Pere Oherubin, 600 Dorsal Cells of Spinal Medulla, 520 Dorset, — Products of Tuberculosis Ba- cillus, 572 — Marion, Crystal Formation in Culture Media, 343 Dorsiventral Organs, Position of, 403 Dots, Pellucid, in Hypericum, 406 Double Pollination, 408 Staining Vegetable Tissue, 592 Doubling of the Fundamental Band of Chlorophyll, 401 Dreissenia polymorpha, 117 Drew, G. A., Anatomy of Sphxrium so- leatum, 117 Drosera, Changes in the Tentacles, pro- duced by Feeding, 220 Drossbach, G. P., Influence of Cerium and Zirconium Groups on the Growth of Bac- teria, 157 Drude, O., Structure of Umbelliferse, 137 Driiner, L., Preparation and Horizontal Binocular Microscope, 431 Dubard, — New Type of Tuberculosis, 571 Dubois, L., Action of Currents of High Frequency on the Virulence of Strepto- cocci, 328 — R., Poisoning Freshwater Animals by Hypochlorite of Lime, 25 Duerden, J. E., Aliciidte, 393 Duggar, B. M., Bacterial Disease of the Squash-Bug, 237 Dunham, E. K., Bacillus capsulatus aero- genes, 328 Dunlop, M. F., Metopidia pterygoida, 289 Durham, H. E., Agglutinative Action of Typhoid-Serum, 68 Duval, Mathias, ‘ Precis d’Histologie,’ 69 Dyar, Harrison G., Larvae of Higher Bombyces, 119 — Variation of Bacteria from Age, 327 Dysentery, iEtiology of, 239 E. Earle, F. S., Parasitic Fungi, 150 Earthworm, New Species, 386 Earthworms from Celebes, 37 Echinocystis and Palseodiscus, 129 Echinoderma. See Contents, xvii Echinoderms, New Zealand, 391 Echinothurid, New, 539 Echinothuridse, Affinities, 130 Ectopavasitic Triclad, New, 210 Edriophthalma from Irish Sea, New, 383 Edwards, A. M., Growing Cell, 79 Eel, Life History, 192 * — Reproduction and Development, 111 Eels, Development of, 356 Effront, J., Caroubinase, A New Hydro- lytic Enzyme, 401 Egg-laying in Rana fusca, 189 I Yolk Agar for Cultivating Gonococcus, 586 Egg- yelk as an Adjunct to Nutritive Media, 78 Elders, E., East African Polychmta, 534 Ehring, C., Colouring-Matter of the To- mato, 214 Eimer, G. H. Th., Evolution on Definite Lines, 108 Eisen, G., Notes on Fixation, Alcohol Method, Stains, &c., 590 — Plasmocytes, 271 Eismond, J., Photomicrography, 170 Elasipoda of the ‘ Travailleur ’ and ‘ Talis- man,’ 43 Electric Arc, Application of, to Photo- micrography, 600 — Organs of the Ray, Demonstrating the, 592 Electricity, Effect of, on Vegetation, 412 — Influence of, on Germination, 142 — — on Growth of Plants, 142 Ellis, J. D., JEcidiella, 320 — W. G. P., Fungus Parasitic on Pellia, 567 Embiidse, 372 Embryo-Sac of Succulent Plants, 51 Embry ogeny and Fertilisation in Lilium, 552 — and Fertilisation of Triticum, 553 — of Conifers, 309 — of Sagittaria, 408 — of Salix, 309 — of Veronica, 308 Embryologjq Experimental, 269 — of Balanophoraeese, 51 I — of Nautilus, 116 — of Starfish, 129 — Phanerogams. See Contents, xxi — Vertebrates. See Contents, vii — Vertebrate, Problems of, 109 Embryonic Shell of Bivalves, 279 — Variations of Growth, 17 Emery, C., Lines of Variation and Ger- minal Selection, 193 Emmerling, O., Bacillus forming Butyuc Acid from Glycerol, 241 — Butylalcohol Fermentation, 559 — Fermentation produced by Mould, 313 Emulsion and Sediment-Figures produced by Motile Bacteria, 236 Enamel, Tubular, 521 2 U 1897 616 INDEX. Encapsuling of Starch-Grains, 135, 544 Encrusting and Perforating Algse, 417 Endoderm and Pericylein Trifolium, 136 Endophytic Mvcorliiza, 318 Endosperm, Formation of, in Leucojum, 213 Energids and Cells, 519 Enlarged Photomicrographs, 348 Enoch, F., Male of Prestwichia aquaticci, 529 — Mymaridse, 255 Enteritis, Streptococcus of, 577 Entomogenous Fungi, 419 Entomostraca of Lake Mezzola, 124 — South African, 205 Entozoic Tuberculous New Formations, 293 Epidemic among Pigeons caused by Ba- cillus coli communis , 67 Epiderm and Periderm, Formation, 304 Epidermis Folds on Palms and Soles of Primates, 195 Epigamy and Schizogamy, 36 Epiphyllous Algae, 227 Epithelium of Triclads, 390 Epitrichium of the Chick, 270 Erbe, C., Improved Cathcart Microtome, 589 — Microtome with Metzner’s Double Sup- port Guidance, 590 — Weigert’s Microtome, 590 * Eriksson, J., Latent Life iii the Urodinese, 232 — Puccinia graminis, 61 — Rusts of Corn, 321 Erlanger, R. von, Attraction-Spheres in Spermatogenesis, 192 Ernst, P., Gram’s Method, 84 Erythroblasts and Leucoblasts, Distinction between, 271 Eschar a lapidescens , van Baster, 118 Escherich, R., Function-Change in Moult- ing Hairs of Insects, 378 Eschle, — Iodine in Algae, 417 Escombe, F., Cell-Membrane of Lichens, , 231 Etard, A., Doubling of the Fundamental Band of Chlorophyll, 401 — Spectrum of Chlorophyll, 48 Eucope, Variations, 132 Euglena sanguinea, 542 Eurotiopsis Gayoni , 152 Evolution, Anticipation of Modern Views on, 364 — Influence cf the Gradual Cooling of the Globe on, 275 — on Definite Lines, 108 Ewart, A. J., Aerotropism of Roots, 221 — Assimilatory Inhibition, 311 — Evolution of Oxygen from Coloured Bacteria, 569 — Vitality of Seeds, 219 — J. Cossar, Critical Period in Develop- ment of Horse, 515 [ Ewell, E. E., Apparatus for Preparation of Roll Cultures of Anaerobic Organisms, j 339 Examining for Bacteria in Cover-Glass Preparations, 444 I Excretion of Bacteria by the Animal Bodv, 426 j — of Drops of Water from Leaves, 557 Excretory Cells of Ascaridse, 535 i — Organs and Blood- Vascular System of Tetrastemma grxeense , 127 | Development of, in Bdellostoma, 356 of Ascarids, 388 i — System of Nematodes, 289 j Exobasidium Vitis, 567 | Exormotheca, 316 Eye of Corycasus, 382 Eye-pieces. See Contents, xxx Eyes of Hirudinea, 288 — of Turbellaria and other Flat Worms, 293 F. Facciola, L., Micrococci of Malaria, 426 Familler, J., Degradation and Transforma- tion of Sexual Organs, 141 — Non-Sexual Propagation of Campylopus | jlexuosus, 561 j Fangs of Adder, 192 | Farmer, J. B., Vegetable Cytology, 47 Fattiness of Lepra and Tubercle Bacilli, 573 Fauna of Baikal Lake, 524 Fere, Ch., Removal of Shell from Develop- ing Ova, 269 Fermentation, Chemistry of, 559 — Alcoholic, without Yeast, 222, 414 — Butylalcoliol, 559 — Flasks, New Stopper, 80 — of Phanerogams. See Contents, xxiii — produced by Moulds, 313 ! Fermentative Power, 222 l Ferraud, — ., Notes on the Agglutination , Phenomenon of Typhoid Serum, 347 | Ferrophilous Bacteria, 570 I Fertilisation and Embryogeuy in Lilium, 552 [ — and Embryogeuy of Triticum, 553 — and Maturation in Amphioxus, 353 in Gastropod Ova, 369 | in Prosthecerieus vittatus , 210 — Artificial, of Rabbit’s Ova, 188 — Cross-, and Self-Fertilisation, 141 — of Bromeliaceae, 21S — of Cycas, 140 of Salisburia, 140 — of Spring Flowers, 309 Fever, Texas, ^Etiology of, 46 Ficalbi, E., Revision of European Culi- cidse, 529 Filaments, Twisting of, 139 I Filaria nocturna, 37 INDEX, 617 Filaroides in Frontal Sinuses of Skunks, 208 Fink, B., Cross-Fertilisation and Self- Fertilisation, 141 Fischel, A., Embryonic Variations of Growth, 17 — Pigment-Cells, 22 • — Structure of Cyanophycese and Schizo- mycetes, 423 Fischer, E., Tuberaceoe, 59 — Tuberacese and Gasteromycetes, 153 — H , Structure and Affinities of Pleuro- tomaria, 277 Fishes, British, Life-Histories, 111 Fishing Net, Closing, 582 Fixation, Alcohol Method, Stains, &c., 590 — of Celloidin Sections, 451 Fixing and Staining, Microscopical Pre- parations, Combined Method of, 591 Flagella of Plague Bacillus, Demonstrating Presence of, 588 — - Staining, 251 Flagellata, New, 299 Flask for Bacteria and High Tension, 580 Flat-Fish, Passage of the Eye in a, 517 Flatters, A., Simple Microtome for Biolo- gical Work, 344 Flavour-producing Micrococcus of Butter, 430 Flemming, W., Influence of Heat and Light on Pigmentation of Salamander Larvae, 19, 195 Flexner, S., Pseudo-Tuberculosis Hominis Streptotricha, 430 Floderus, Matts, Amitotic Nuclear Division in Egg of Hedgehog, 17 Floral Leaves without Vascular Bundles, 138 Flower and “ Nipples ” of Salisburia, 215 — Development of the, 403 Flowers, How they attract Insects, 121 — - of Salix, Variation in, 138 Follicle-Cells in Salpa, 367 Food-Material of Algae and Fungi, 562 — Reserve, 48 Foot and Mouth Disease, iEtiology of, 575 Report of German Commission, 574 Foot, K., Origin of the Cleavage Centro- somes, 515 Foraminifera of the Adriatic, 132 — of the Gault of Folkestone, 598 Forbes, E. B., North American Species of Cyclops, 533 — S. A., Bacteria Normal to Digestive Organs of Hemiptera, 327 Form and Metabolism of the Cell, Relation between the, 270 Formaldehyd, Demonstration of Small Quantities, 178 Formalin Vapour, Penetrating Power of, 453 Foslie, M., Melobesiaceae, 417 Fossil Algae, 562 — Bacteria, 157 — Fungi, 323 — Plants of the Coal-Measures, 55 Foulerton, A. G. R., Agglutination Phe- nomenon in Glanders, 242 Fowler, G. H., Plankton of the Faeroe Channel, 199 Fox, T. C., Cultivation Medium for Ring- worm Fungi, 79 — Ringworm Fungi, 61 Fragmentation in Lineus gesserensis, 208 Francaviglia, M. C., Helminthological Notes, 536 France, R. H., Chlorogonium, 317 Franz, K., Development of Hypochorda and Ligamentum longitudinale ventrale in Teleostei, 356 Fraser, — ., Antivenomous and Antitoxic Qualities of the Bile of Serpents and of other Animals, 570 Freezing of Formol, To Prevent, 346 — of Plants, 560 Frenzel, J., Dreissenia polymorphci , 1 17 — Plankton-Methods, 442 — The Plankton Pump, 199 Freshwater Algae, New African Genera, 316 of the South of England, 467 — Crustacea of South Africa, 285 — Fauna of South Africa, 275 — — of the Azores, 26 — Nematodes of Hungary, 290 — Ostracods of North America, 286 Freudenreich, E. von, Bacteriological Examination of Water for Coli Bacteria, 66 — Kefir, 232 — Microbic Agents of Cheese-Ripening, 325 Friedenthal, H., Influence of Induced Current on Bacteria, 65 Froggatt, \V. W., Bag-Shelter of Larvae of Australian Moths, 28 Frogs, Sensitiveness to Infection with. Plague, 570 Fron, G., Root of Suaeda and Salsola, 552. Frosch, — ., Report of the German Com- mission on Foot and Mouth Disease, 574 — P., Cultivation of Amoeba, 584 Fruit and Seed of Viscum, 548 — in Ranunculaceae, Structure, 404 ' — of Argania Sideroxylon , 548 — of Phoenix melanocarpa, 50 bearing, Influence of, on Development of Mechanical Tissue, 135 Fry, Sir E., Alternation of Generations,. 314 Fucaceae, 57 Fuess, R., New Stand, with Polariser and Large Illuminator, 578 Fuhrmann, Olto, Fauna of Alpine Lakes. 200 2 U 2 618 INDEX. Fujii, K., Flower and “Nipples” of Salis- buria, 215 Fulgur, Yolk-Lobe and Centrosome of, 117 Function-Change in Moulting Hairs of Insects, 378 Fungi. See Contents, xxv — inhabiting Excrement, 565 — New Genera of, 58, 564 — Parasitic on Lichens, 565 Fungus Parasitic on Pellia, 567 Funiculina and Kophobelemnon, 132 Fusicladium, 152 — and Venturia, 321 Futterer, W., Anatomy of Zingiberacese, 137 G. Galeodidm, 380 Galeotti, G., Preparing Plague-Serum, 248 Gallionella, 569 Galloway, B. T., Coleosporium Pint, 152 Galls, Danish, 280 Galton, Francis, Law of Heredity, 514 Gamasidse, Structure of, 122 Gamotropic and Carpotropic Movements, 412 of Flowers of Grasses, 144 Ganglion-Cells, Giant, in Spinal Cord of Flat-Fishes, 196 Ganoid Scales, Minute Structure, 112 Garbasso, A., Coloration of Scales in Beetles, 120 Garino, E., Bacillus denitrificans agilis, and Denitrification, 575 Garstang, W., Functions of certain Dia- gnostic Characters of Decapod Crusta- cea, 123 — Notes on Crabs, 203 Gases produced by Bacteria, 65 Gasperini, G., Actinomycosis, 153 Gasteromycetes and Tuberacem, 153 Gastropod, New, in an Antarctic*Holothu- rian, 369 Gastropoda. See Contents, xi Gastrula, Double, in Lizard, 518 — of Amphioxus, 357 Gaucher, L., Ovary of Pomegranate, 306 Gayot, L. A., Archegono of Muscinem, 315 Gebhardt, W., A Simple Apparatus for taking Slightly Enlarged Stereoscopic Photographs, 170 — Isolation of the Elements of the Crystal- line Lens, 173 — Straighteniug Paraffin Sections, 449 Gehuchten, A. van, Dorsal Cells of Spinal Medulla, 520 Geisse, — Life-History of Trichina, 20S Gelatin Method for Imbedding Objects for Exhibition, 82 Gemma? of Aulacomnium, 417 Gemmill, J. F., Hermaphroditism of Lim- pet, 27 Gemmill, J. F., Oogenesis in Anura, 189 Genital Ducts of Teleosteans, 20 Genthe, K. W., Mouth-Parts of Microlepi- doptera, 529 ! Geoglossese, 419 j Geophilous Plants, 215 i Geothallus, Development, 146 Gerassimoff, J. J., Method of Staining Non-Nucleated Cells, 175 — Non-Nucleated Cells, 134 ! Gerber, C., Tannins in Fruits, 303 ; — G., Influence of Temperature and Nu- triment on the Respiration of Fungi, 313 ‘ Germ Life, Story of,’ 577 Germanos, N. K., Gorgonacea of Ternate, 298 ! Germinal Selection, 107 and Lines of Variation, 193 — Vesicle and Polar Bodies in Batrachia, 353 Germination of Almond, 312 — of Barley, 142, 219 — of Cryptocoryne, 411 — of Phanerogams. See Contexts, xxii Ghadially, — ., Micrococcus Ghadiallii, 428 Giard, A., Historical Note as to Polar Bodies, 516 — Hypotypic Regeneration, 515 Gibson, R. J. Harvey, Leaves of Selagi- nella, 223 Giesbrecht, W., Development of Monstril- lidse, 204 - — Systematic Notes on Copepods, 383 i Giesenhagen, K., Bulbils of Characese, 147 — Shoot Nodes of Characese, 416 Giglio-Tos, E., Blood of Lamprey, 112, 355 — Red Blood-Corpuscles, 197 Gilchrist, J. D. F., Mode of Life of Lima hians , 26 — J., Nervous System of Molluscs, 369 — T. C., Presence of an Oidium in Pseudo- lupus vulgaris, 322 Giles, G. M., A Simple Method of Photo- micrography by an Inexpensive Appa- ratus, 164, ISO Gill, Th., Some Questions of Nomenclature, 274 Gills, Larval, of Odonata, 30 Gilson, G., Larval Gills of Odonata, 30 — Septal Values of Owenia, 386 — Thoracic Glands in Larva? of Tricho- i ptera, 30 Giltay, E., Transpiration in the Tropics, 556 1 Ginger-Beer Plant, 425 Girard, A., Fruit of Phoenix melanocarpa , 50 Gizzards of Odonata, 31 Gjokic, G., Fruit and Seed of Viscum, 548 i Gland, Thyroid, Development of, in Man, 189 — Unpaired, of Hsementaria, 125 INDEX. 619 Glands, Buccal, of Larval Trichoptera, 121 — Lymphatic, of Nereids, 37 — Mandibular, of Cossus ligniperda, 119 — of T PRINTED BY WM. CLOWES AND SONS, LIMITED] [STAMFORD STREET AND CHARING CROSS. WILLIAMS & NORGATE, BOOKSELLERS AND PUBLISHERS, Some Recent Important Purchases and Importations. ELLIOTS. The New and Heretofore Un- tigurec! Species of die Birds of North America. 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London, 1880-81. £3. MILNE EDWARDS (H.). Le§ons sur la Physiologie et l’Anatomie Comparee de Phomme et des animaux. 14 vols. 8vo, neatly bound in half calf. Paris, 1857-81. (250 frs.). £5 5s. HASSEL (A. H.). A History of the British Freshwater Algae, including Descriptions of the Desmideae and Diatomaceae. With upwards of 100 plates illustrating the various species. 2 vols. 8vo, original cloth. Very scarce. London, 1845. £3. WILLIAMS & NORGATE, 14 HENRIETTA STREET, COVENT GARDEN, LONDON ; 20 SOUTH FREDERICK STREET, EDINBURGH i and 7 BROAD STREET, OXFORD. CONTENTS TRANSACTIONS OF THE SOCIETY. PAGE VI. — On the Development and Structure op Dental Enamel. By J. Leon Williams, D.D.S., L.D.S., F.R.M.S. (Plates II.-V.) 261 SUMMARY OF CURRENT RESEARCHES. ZOOLOGY. VERTEBRATA. a. Embryology. PAGE Hertwig, O. — Experimental Embryology 269 Fere, Ch. — Removal of Shell from Developing Ova 269 Hammar, J. A. — Protoplasmic Connections between Blastomeres 270 Montgomery, T. H., Jun. — Mesoderm and Body-Cavities 270 Bosenstadt, B. — Epitrichium of the Chick 270 b. Histology. Verworn, M. — Relation between the Form and the Metabolism of the Cell .. .. 270 Bambeke, Ch. van — Cell-boundaries 270 Eisen, Gustav — Plasmocytes 271 Trambusti, A. — Distinction between Leucoblasts and Erythr oblasts 271 Juschtschenco, A. J. — Sympathetic Ganglion-Cells 271 Demoor, J. — Plasticity of Cerebral Neurones 272 c. General. Jaeger, G. — Problems of Nature 272 Pearson, K. — Chances of Death 272 Hyatt, A. — Ontogeny and Phytogeny .. .. 273 Verrill, A. E. — Nocturnal Protective Coloration 274 Varigny, H. De — Air and Life 274 Gill, Th. — Some Questions of Nomenclature 274 Quinton, K. — Influence of the Gradual Cooling of the Globe on Evolution . . . . 275 Zachartas, H. C. E. — Evolution of Head-Scales in Boidx 275 Stahr, H. — Function of the Lateral Organs 275 Weber, M. — Freshwater Fauna of South Africa 275 Willey, A. — New Amphioxus 275 mVERTEBRATA. Gratacap, L. P. — Hard Parts of Invertebrata 276 Call, R. E. — New Discoveries in the Mammoth Cave 276 Ortmann, A. E. — Distribution of Marine Organisms 276 Mollusca. Baker, E. C. — Pulsations of the Heart in Molluscs 276 a. Cephalopoda. Willey, A. — Notes on Nautilus 277 Verrill, A. E. — The Florida Sea-Monster 277 y. Gastropoda. Bouyier, E. L., & H. Fischer — Structure and Affinities of Pleurotomana .. .. 277 Hecht, E. — Multiple Reno-Pericirdial Canals in Elysia viridis 277 A 2 PAGE 5. Lamellibrancliiata. Chatin, J. — Clasmatocytes in Lamellibranchs 278 Rice, E. L. — Classification of Lamellibranchs based on the Gills 278 Bernard, F. — Embryonic Shell of Bivalves 279- Arthropoda. Jaworowski, A. — Appendages of Arthropods 279' a. Insecta. Hart, C. A. — Aquatic Insects of the Illinois Biver 279 Lallier, P. — Myasis of Alimentary Canal in Man 279 Heymons, R. — Viviparity in Ephemerids 279 Muraoka, H. — Luminosity of Glowivorms 280 Butler, A. G. — Seasonal Dimorphism in African Butterflies 289 Labouleene — Zeuzera JEsculi 280 Keny’ON, F. C. — Optic Lobes of Bee’s Brain 280 Rostrup, S. — Danish Galls 280' Kellicott, D. S. — Odonate Nymph from a Hot Spring 280 Smith, J. B. — Mouth-Parts of Insects 280 Bordas, L. — Classification of Orthoptera 281 Heymons, R. — Development of Apterygota 281 Cockerell, T. D. A. — Check-List of Coccidx 281 Morse, E. S. — Mosquito-Bite 281 Alcock, A. — Natural Repellent Effect of “ Warning Colours ” 282: Izquierdo, V. — Ejection of Offensive Liquids by Insects 282 Mayer, A. G. — Colours of Lepidopter a , . . .. 282 Czertvinski, K. — Notes on Termites 282 Johnson, W. G. — New Scale-Insects 288- 5. Arachnida. Bambeke, Ch. van — Oogenesis in Pholcus 283 Wasmann, E. — Mites and Ants 283 €. Crustacea. Newbigin, M. I. — Pigments of Lobster 283 Parker, G. H. — Photomechanical Changes in Retinal Pigment-Cells of Palxmonetes 284 Ortmann, A. E. — Trapeziidx 285 Henderson, J. R. — New Paguridx 280 Weber, M. — Freshwater Crustacea of South Africa 285 Saks, G. O. — Mysidx of the Caspian 285 N£mec, B. — New Cave lsopod 285 Sars, G. O. — Amphipods of the Caspian 285 Alcock, A. — Neio Species of Branchipus 289 Sharpe, R. W. — North American Freshwater Ostracods 286- Scourfield, D. J. — Olfactory Setx of Cladocera 286 Ross, L. S. — Some Manitoba Cladocera 286 Topsent, E. — Pycnogonids 289 Annulata. Mead, A. D. — Ovum Centrosome in Chxtopterus 289 Hescheler, K. — Regeneration and Autotomy in Earthworms 287 Smith, F. — New North American Oligochxta 287 Michaelsen, W. — New Oligochxta 287 Nusbaum, J., & Jan Rakowski — Heart-Body of Enchytrxidx 287 Hesse, R. — Eyes of Hirudinea 288 Rotatoria. Stokes, A. C. — Some new Forms of American Rotifera 288 Shephard, T. — Lacinularia elongata, a new Rotifer . . . . 288 Rousselet, C. F. — Brachionus bakeri and its Varieties 288 Dunlop, M. F. — Metopidia pterygoida , a new Rotifer 289 Nem atohelminthe s . Linstow, v. — Classification of Nematoda 289 Nassonow, N. — Excretory System of Nematodes 289 Chatin, J. — Alleged Nematode-Parasites of Truffles 289 Linstow, v. — Molin' s GenUs Globocephalus 289 Romer, F. — Classification of Gordiidx 290 Lataste, F. — Gordius and Mantis .. .. 290 Daday, E. v. — Freshwater Nematodes of Hungary 290 3 PAGE Platyhelminth.es. Lebedinski, J. — Development of Nemerteans 290 Montgomery, T. H., Jun. — New Metanemerteans 291 „ „ Nephridia of Stichostemma 292 Villot, A. — Species of Ophryocotyle 292 Hatjsmann, L. — Trematodes of Freshwater Fishes 292 Diamare, V. — Entozoic Tuberculous New Formations 293 Bensley, R. R. — Two Forms of Distomum cygnoides 293 Hesse, R. — Eyes of Turbellaria and other Flat Worms 293 Willey, A. — Remarkable new Planarian .. .. 293 Plehn, M. — Three new Polyclads 294 Incertae Sedis. Willey, A. — Ptychodera 294 „ „ Ctenoplana 295 Echinoderma. Perrier, E. — Asteroidea of the North Atlantic 296 Kohler, R. — Deep-Water Ophiuridse from Indian Ocean 296 jOstergren, Hj. — Use of the Anchors in Synapta 296 Dendy, A. — New Zealand Holothurians 297 Coelentera. Schultze, L. S. — Classification of Antipatliaria 297 Schenk, A., & Kekenthal — Neiv Alcyonaria 298 Germanos, N. K. — Gorgonacea of Ternate 298 Ivwietniewski, C. R. — Actiniaria of Ternate 298 Ostrooumoff, A. — Craspedota 298 Campenhausen, B. v. — Eydroids of Ternate 298 Hickson, S. J. — Ampullx in Millepora 299 Porifera. Doderlein, L. — Lithonina 299 Protozoa. 'Verworn, M. — Physiology of the Cell 299 Meyer, Hs. — New Flagellata 299 Butschinsky, P. — Protozoa of Salt Lakes 300 Karawaiew, W. — New Radiolcirian 300 Rimsky-Korsakow, M. — New Holotrichous Infusorian 300 Wallengren, Hs. — Species of Trichodina 300 Labbe, A., & E. G. Racovitza — New Gregavine 300 Leger, L. — Coccidia of Myriopods 300 ,, ,, Life-Cycle of Coccidia 301 BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. Cl) Cell-structure and Protoplasm. Pfeffer, W. — Influence of the Nucleus on the Formation of the Cell-Wall .. .. 302 Calkins, G. N. — Chromatin-reduction and Tetrad-formation in Pteridophyta .. 302 Molliard, M. — Cdl-hypertrophies produced by Galls 302 C2) Other Cell-contents (including: Secretions). Ryvtosch, S. — Oil in Leaves 303 Ourtius, T., & J. Reinke — Volatile Reducing Substance in Green Cells 303 Gerber, C. — Tannins in Fruits 303 Lijtz, L. — Production of Hydrocyanic Acid in the Pomex 303 (3) Structure of Tissues. "Czapek, F. — Leptome of Angiosperms 303 Tittmann, H. — Formation of Periderm and Epiderm 304 Matteucci, E. — Cork-Growths 304 Paratore, E. — Supernumerary Vascular Bundle in a Root 304 Kuster, E. — Anatomy of Chrysobalanex 304 Grevel, W. — Structure of Diapensacex 305 Jumelle, H. — Anatomy of Cissus gongylodes 305 4 (4) Structure of Organs. page Molisch, H. — Influence of the Soil on ilie Colour of Flowers 305 Clos, D. — Homology of the Anther 305 Gaucher, L. — Ovary of the Pomegranate 306 Worsdell, W. C. — Ovule of Christisonia 306 Macchiati, L. — Seeds of Papilionaceae 306 Chatin, A. — Symmetry of the Appendicular Organs 306 Mattej, G. — Bed Spots on Leaves 306 Went, F. A. F. O. — Dimorphic Branches of Castilloa 307 Baldrati, I. — Scales of the Bulbs of Allium 307 Keller, I. A. — Underground Bunners 307 Rimbach, A. — Contractile Boots of Arum 307 Thiselton-Dyer, W. T. — Evolution of the Cyclamen 307 Tieghem, P. van — Structure and Affinities of the Grubbiaceae 308 Candolle, C. de — Vegetable Teratology 306 £?. Physiology. (1) Reproduction and Embryology. Meunier, A. — Embryogeny of Veronica 308 Chamberlain, C. J. — Embryogeny of Salix 300 Coulter, J M. — Embryogeny of Conifers .. 300 Hart, J. H. — Pollination by Bats 309 Burrill, J. H. —Fertilisation of Spring Flowers 309 Hansgirg, A. — Germination of Pollen- Grains 316 (2) Nutrition and Growth (including Germination and Movements of Fluids). Kohl, F. G. — Assimilating Energy of the Blue and Violet Bays of the Spectrum .. 316 Daniel, L. — Beciprocal Influence of Stock and Graft on one another 316 Vandervelde, A. J. J. — Influence of Chemical Beagents and of Light on Germina- tion 316 Burnett, K. C. — Influence of Light on Dorsiventral Organs 311 Ewart, A. J. — Assimilatory Inhibition 311 Reiche, K. — Biology of Woody Plants 311 Lopriore, G. — Begeneration of Split Boots 311 Buhgerstein, A. — Transpiration of Tropical Plants 312 (3) Irritability. Jost, L. — Periodic Movements of the Leaves of Mimosa in the Dark 312 Bullot, G. — Growth and Curvature of Phycomyces 312 (4) Chemical Changes (including Respiration and Fermentation). Pfeffer, W. — Formation of Diastase 312 Sablon, Leclerc du — Germination of the Almond 312 Emmerling, O. — Fermentation produced by Moulds 316 Gerber, G. — Influence of Temperature and Nutriment on the Bespiration of Fungi 316