2.4 L, 2> ItibrarD of % ®useum OF COMPARATIVE ZOOLOGY, AT HARVARD COLLEGE, CAMBRIDGE, MASS. Journal OF THE Royal Microscopical Society; CONTAINING ITS TRANSACTIONS AND PROCEEDINGS, AND A SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY Ps. 1ST ID BOTANY (principally Invertebrata and Cryptogamia), MICROSCOPY, <3cc_ Edited by F. JEFFREY BELL, M.A., One of the Secretaries of the Society and Professor of Comparative Anatomy and Zoology in King's College ; WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND A. W. BENNETT, M.A., B.Sc., F.L.S., | J. ARTHUR THOMSON, M.A., Lecturer on Botany at S t. Thomas's Hospital, | Lecturer on Zoology in the School of Medicine, R. G. HEBB, M.A., M.D. ( Cantab.f and Edinburgh, FELLOWS OF THE SOCIETY. FOR THE YEAR 1893. Part 2. A LONDON : TO BE OBTAINED AT THE SOCIETY’S ROOMS, 20 HANOVER SQUARE, W. ; of Messrs. WILLIAMS & NORGATE ; and of Messrs. DULAU & CO. The Journal is issued on the third Wednesday in February, April, June, August, October, and December. 4> 1893. Part 4. AUGUST. [To Non-Fellows, Price 6s. \ Journal OF THE Royal Microscopical Society; CONTAINING ITS TRANSACTIONS AND PROCEEDINGS, i AND A SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY BOTANY (principally Invertebrata and Cryptogamia), MICROSCOPY, <3cc- Edited by F. JEFFREY BELL, M.A., One of the Secretaries of the Society and Professor of Comparative Anatomy and Zoology in Kings College ; WITH THE ASSISTANCE OF THE PUBLICATION COMMITTEE AND J. ARTHUR THOMSON, M.A., Lecturer on Zoology in the School of Medicine , Edinburgh, A. W. BENNETT, M.A., B.Sc., F.L.S., Lecturer on Botany at St. Thomas’s H ospital, R. G. HEBB, M.A., M.D. ( Cantab .), and FELLOWS OF THE SOCIETY. ' LONDON: TO BE OBTAINED AT THE SOCIETY’S ROOMS, 20 HANOVER SQUARE, W.; of Messrs. WILLIAMS & NORGATE; and of Messrs. DULAU & CO. PRINTED BY WM. CLOWES AND SONS, LIMITED] [STAMFORD STREET AND CHARING CROSS. CONTENTS. Transactions of the Society — PAGB VIII. — Notes on some of the Digestive Processes in Arachnids. By Henry M. Bernard, M.A. Cantab., &c. (Plate VI.) .. 427 IX. — On Floscularia pelagioa sp. n., and Notes on several other Rotifers. By Charles F. Bousselet, F.R.M.S. (Plate VII.) 444 X. — List of New Rotifers since 1889. By Charles F. Rous- selet, F.R.M.S. 450 SUMMARY OF CURRENT RESEARCHES. ZOOLOGY. A. VERTEBRATA : — Embryology, Histology, and General. a. Embryology. Henneguy, L. F. — Parthenogenetic Segmentation of Ova of Mammals 459 Perenyi, J. — Origin of Mesoderm 459 Schottlaender, J. — Origin and History of the Graafian Follicle 460 Fleischmann, A. — Placenta of Rodents 460 Willey, A. — A Duck with Drake’s Plumage 461 Scheel, C. — Development of the Teleostean Vertebral Column 461 Goeppert, E. — Development of the Pancreas 461 j8. Histology. Van der Stricht, O. — Attractive Sphere 462 Bizzozero, G. — Nuclear Division in Cut Nerve-fibres 462 Kallius, E. — Neuroglia-cells in Peripheral Nerves 462 Frenzel, J. — Cell-multiplication and Replacement *. .. 462 y. General. Lilienfeld, L., & A. Monti — Phosphorus in the Tissues 463 B. INVERTEBRATA. Mollusca. y. Gastropoda. Griffiths, A. B. — Olfactory Organs of Helix 463 Bergh, R. — Opisthobranchs of the 1 Hirondelle ’ 463 Wackwitz, J. — Histology of Muscle in Heteropods and Pteropods 463 Hedley, E. — Range of Placostylus 464 5. Lamellibranchiata. Chatin, J. — Ocular Nerves of Spondylus gcederopus 464 Lotsy, J. P. — Food of Oysters , Clams , and Mussels 464 Boehm, G. — Pedal Impression of Pachyerisma .. .. 464 „ „ Lithiotis problematica Giimbel 464 Molluscoida. a. Tunicata. Salensky, W. — Origin of Metagenesis in Tunicata 464 Jourdain, S. — Deglutition in Synascidise 465 Salensky, W. — Nervous System in Embryos of Distaplia 465 Brooks, W. K. — Origin of Organs of Salpa 466 „ „ Nutrition of Embryo of Salpa 467 Metcalf, M. M. — New Species of Octacnemus 467 B. Bryozoa. Gregory, J. W. — Classification of Cheilostoma 467 y. Brachiopoda. Blochmann, F. — Structure of Brachiopoda 468 Arthropoda. a. Insecta. Buckler, W., & others — Larvae of British Butterflies and Moths 468 Watson, E. Y. — Classification of Hesperiidse 468 3 PAGE Swinhoe, C. — Mimetic Forms of Hypolimnas 469 Forel, A. — Ants' Nests 469 „ „ Notes on Ants 469 Bos, J. Ritzema— The Pharaoh-Ant 469 „ „ Change of Diet in a Beetle 470 Rath, O. vom — Reducing Division in Spermatogenesis of Gryllotalpa 470 Schaff, E. — A Diluvial Cockroach 470 Dahl, F. — Halobatidse of Plankton Expedition 470 /3. Myriopoda. Adensamer, T. — Eye of Scutigera coleoptrata 470 Verhoeff, C. — A new Stage in the Development of Male Iulidse 471 5. Araclmida. Hessler, R. — Extreme Case of Parasitism 471 Cal sard, M. — Circulatory Apparatus of Mygale csementaria 471 e. Crustacea. Herrick, F. H. — Cement Glands of Lobster 471 Haecker, V. — Protective Adaptations in Crabs 472 Royal Academy of Amsterdam— Limnoria lignorum 472 Brauer, A. — Parthenogenetic Ova of Artemia salina . . 472 Herrick, F. H. — Podopsis .. .. 473 Vermes, o. Annelida. Buchanan, F. — Peculiarities in Segmentation of Pohjchsete s 473 Apstein, C. — A leiopidee of Berlin Museum 474 Bonnier, J. — Maxillary Apparatus of Euniceidee 474 Goodrich, E. S. — New Organ in the Lycoridea 474 Ehlers, E. — Arenicola marina 474 Wawrzik, E. — Supporting Tissue of the Nervous System 475 Benham, W. B. — New Species of Nais 475 Beddard, F. E. — Anatomy of Sutroa 475 Benham, W. B. — New Moniligaster 476 Blanchard, R. — Notes on Hirudinea . . . . 476 j8. Nemathelminthes, Wasielewski, von — Germinal Zone of Ascaris megalocephala . . .. 477 Linstow, von — Oxyuris Paronai and Cheiracanthus hispidus » . 477 y. Platyhelminthes. Haswell, W. A. — Turbellarian in Underground Waters .. .. .. .» .. », 477 „ „ New Genus of Temnocephalese 477 Verrill, A. E. — Marine Planar ians of New England 477 „ „ Dinophilidse of New England 478 „ „ Marine Nemerteans of New England and adjacent Waters . . . . 478 Plessis, G. du — Nemertea of Lake Geneva 478 Dendy, A. — Reproduction of Geonemertes australiensis 478 Gamble, F. W. — British Marine Turbellaria 479 Lang, A. — Cercaria of Amphistomum subclavatum 479 Will, H. — Anatomy of Caryophyllseus mutabilis 479 Stossich, M. — Helminthological Notes 480 5. Incertae Sedis. Glascott, L. S. — Irish Rotifers 480 Bergendal, D.— Rotatoria of Greenland 481 Daday, E. v.—Rotifera of the Gulf of Naples 481 Wierzejski, A., & O. Zacharias — New Freshwater Rotifers 481 Bryce, D. — Adinetidx 482 Western, G. — Notes on Rotifers 482 Haswell, W. A. — Phoronis from Port Jackson 482 Bohmig, L. — Minute Anatomy of Rhodope Veranii 482 Wagner, F. v. — Gastrotricha 483 Echinoderma. MacBride, E. W. — Development in Asterina gibbosa 483 Loeb, J. — Cleavage of Eggs of Arbacia .. 484 4 PAG ft Bell, F. Jeffrey — Crinoids from Sahul Bank 484 Ludwig, H. — Holothurians from the Eastern Pacific . 484 Ccelentera. Beecher, C. E. — Development of a Palaeozoic Poriferous Coral 486 „ „ Symmetrical Cell-development in Favositidae 486 Brook, G. — Affinities of Madrepora 487 Appellof, A. — Edwardsiae 487 Greig, J. A. — Norwegian Pennatulida 488 Chapeaux, M. — Organs of Relation of Hydromedusae 488 Sigerfors, C. P. — Formation of Blastostyle Buds in Epenthesis McCradyi .. .. 488 Bigelow, R. P. — Polydonia frondosa 489 Murbach, L. — Development of Stinging Organs in Hydroids 489 Claus, C. — Development of the Scyphostoma 490 Antipa, Gr. — A new Stauromedusa 490 Hartlaub, C. — Classification of Anthomedusae 491 Zoja, R. — A new Hydroid 491 Porifera. Dendy, A. — Australian Calcar ea Heteroccela 491 Topsent, E. — Sponges of the Hirondelle 491 Weltner, W. — Gemmules of Spongillidae 492 Protozoa. Franze, R. — Stigmata of Mastigophora 492 Balbiani, E. G. — Merotomy of Ciliated Infusoria 492 Lister, J. J. — Reproduction of Orbitolites 493 Rhumbler, L. — Depositions within Foraminifera 494 Gruber, A. — Nuclear Division and Spore-formation in Rhizopods 494 Labbe, A. — Dimorphism in Development of Haematosporidia 494 BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-structure and Protoplasm. Kienitz-Gerloff, F. — Streaming of Protoplasm and Transport of Nutritive Sub- stances 495 Overton, E. — Reduction of the Chromosomes in Nuclei 495 Mangin, L. — Pectic Substances in Tissues 495 (2) Other Cell-contents (including Secretions). Zopf, W. — Pigments of the lower Cryptogams .. 496 „ „ New Lichen-add 497 Green, J. R. — Vegetable Ferments 497 (3) Structure of Tissues. Dreyer, A. — Function of the Protecting -sheath 498 Chodat, R. — Sieve-tubes in the Xylem 498 Kruch, O. — Structure of Phytolacca 498 (4) ^Structure of Organs. Baroni, E. — Pollen-grains of Papaveraceae 498 Guignard, L., & others — Development of the Integument of the Seed 498 Lalaune, G. — Anatomical Characters of Persistent Leaves 499 Groom, P. — Influence of External Conditions on the Form of Leaves . . . . . . 499 Balicka-Iwanowska, & H. Ross — Leaves of Irideae 500 Heinricher, E. — Structure of Lathraea 500 Berwick, T. — Cotyledonary Glands of Rubiaceae 501 Chodat, R., & R. Zollikofer — Capitate Hairs with Vibratile Filaments .. .. 501 Groom, P. — Velamen of Orchids 501 Maxwell, F. B. — Roots of Ranuncidaceae 501 5 /?. Physiology. (1) Reproduction and Embryology. Macfarlane, J. M. — Structure of Hybrids Newell, J. H., & others— Cross and Self-pollination Roze, E. — Pollination of Naias and Ceratophyllum Munson, W. M. — Secondary Effects of Pollination Willis, J. C. — Gynodicecism in the Labiatse PAGB 501 502 503 503 503 (2) Nutrition and Growth (including Germination, and Movements of Eluids). Chodat, R. — Effect of the Electric Light on Vegetation Loew, E. — Adaptations for Epiphytism Mulleb-Thurgau, A. — Influence of the Seed on the Development of the Fruit (3) Irritability. Sachs, J. — Latent Irritability Bonnier, G. — Changes of Pressure in Mimosa 504 504 504 504 505 (4) Chemical Changes (including Respiration and Fermentation). Aubert, E. — Physiology of Succulent Plants Detmer, W. — Influence of Light on Respiration . . Belzung, E. — Formation of Sulphates and Nitrates .. 505 .. 506 .. 506 B. CRYPTOGAMIA. Algse. Sauvageau, C. — Parasitic Phseosporese 506 Buffham, T. H. — Reproductive Organs of Prasiola 506 Batters, E. A. — Giffordiat a new Genus of Ectocarpacese 507 Schmidle, W. — Chlamydomonas Kleinii sp. 507 Lagerheim, G. v. — Rhodochytrium, a transitional form between the Protococcacese and the Chytridiacese 507 Mcebius, M. — Tetrasporidium , a new Genus of Algse 508 Fungi. Busgen, M. — Germination of Parasitic Fungi 508 Tubeuf, C., & others — New Parasitic Fungi 508 Costantin, J. — Chanci, a Disease of Mushrooms 509 Baroni, E. — Relationship of Calcicolous Lichens to their Substratum 509 Hieronymus, G. — Structure of Yeast-cells 509 Raum, J. — Granules and Vacuoles of Yeast-cells 510 Hansen, E. C. — Saccharomyces 510 Wortmann, J. — Fermentation Differences of Wine Yeasts 510 Fentzling, K. — Influence of Parasitic Uredinese on the Host-plant 511 Klebahn, H. — Hetercecious Uredinese 511 Richards, H. M. — Development of the Spermogone of Cseoma 512 Halsted, B. D. — Anthracnoses of the Solanacese 512 Humphrey, J. E. — Monilia fructigena 512 Morgan, A. P., & R. Thaxter — Phyllogaster , a new Genus of Phalloidese .. .. 513 Arcangeli, G. — Luminosity of Pleurotus olearius 513 Myxomycetes. Zopf, W. — Labyrinthulese 513 Protophyta. a. Schizophycese. Gomont, M .—Lyngbyese 514 Sauvageau, C. — New Genera of Schizophycese 514 Miquel, P. — Biology of Diatoms 514 /9. Schizomycetes. Forster & Bonhoff — Effect of High Temperatures on Tubercle Bacilli 515 Hankin, E. H. — Origin and Presence of Alexins in the Organism 515 Ritsert, E. — Mucoid Change in Infusions 516 Heider, A. — Efficiency of Disinfectants at High Temperatures 516 Sherrington, C. S. — Escape of Bacteria with the Secretions 517 6 Bastin, A. — Bactericidal Power of the Blood 517 Simmonds, N. — Flies and the Transmission of Cholera 518 Zopf, W. — Sphxrotilus roseus, a new red aquatic Schizomycete 518 Laer, H. van — Saccharobacillus Pastorianus 518 Tizzoni, G., & E. Centanni — Hereditary Transmission of Immunity to Rabies .. 519 Massart, J. — Chemotaxis of Leucocytes and Immunity 519 Frenzel, J . — Structure and Spore- formation of Green Tadpole Bacilli 520 Finkelnburg — Variability of Cholera Bacilli 520 Bang, B. — Bacteriology of Swine-plague 520 Wurtz, R., & R. Leudet — Pathogenic Action of Bacillus lactis 521 Rake, B. — Tuberculosis and Leprosy 522 Fischel, F. — Morphology and Biology of the Tubercle Bacillus 522 Letzerich, L. — Bacillus of Influenza 522 Reblaud, Th. — Bacterium pyogenes and B. coli commune 522 Lewascheff, S. W. — Parasites of Typhus Fever 523 D’Espine & de Marignac — Streptococcus isolated from Scarlatina-blood . . . . 523 MICROSCOPY. Cross & Cole’s HandbooJc of Microscopy 524 a. Instruments, Accessories, &e. Cl) Stands. Reichert’s Travelling Microscope (Fig. 60) 524 „ Preparation Microscope (Fig. 61) 526 „ Movable Stage (Fig. 62) 527 Broavn, G. W., jun. — A Sliding Carriage and Stage for the Microscope (Figs. 63 and 64) 527 The Society of Arts Microscope 529 (3) Illuminating* and other Apparatus. Griffiths, E. H. — Three new Accessories for the Microscope (Figs. 65-68) . . . . 530 Rogers, W. A. — Filar Micrometers 531 Reichert’s New Heating Apparatus (Fig. 69) 531 „ New Cover-glass Measurer (Fig. 70) 532 Sir David Salomons* Electric Lantern (Figs. 71 and 72) 532 (4) Photomicrography. Deck, Lyman S. — New Heliostat (Fig. 73) 534 Sternberg, G. M. — Photomicrographs by Gas-light (Fig. 74) 535 Reichert’s New Photomicrographic Apparatus (Figs. 75-77) 536 (5) Microscopical Optics and Manipulation. Czapski, S. — Theory of Optical Instruments 538 Delage, Yves — On the Subjective Magnitude of the Monocular and Binocular Images in the Hand-lens (Figs. 78 and 79) 539 Ewell, M. D. — Numerical Aperture (Figs. 80 and 81) 542 (6) Miscellaneous. Cole, A. H. — Solution of the Dust Problem in Microscopy (Fig. 82) 546 Visit to Bausch & Lomb’s Factory 548 /?. Technique. (1) Collecting Objects, including Culture Processes. Miqtjel, P. — Culture of Diatoms 550 Elion, H. — Cultivating Ascospores on Clay Cubes 550 Sander — Growing Tubercle Bacilli on Vegetable Nutrient Media 550 Pannwitz — Impervious Self-acting Self -regulating Stopper for Sterilizing Purposes 551 Esmarch, von — Improvising Bacteriological Apparatus 551 Schill — Rapid Demonstration of Cholera Bacilli in Water and Faeces 551 K.OCH, R. — Present Position of the Bacteriological Diagnosis of Cholera 552 „ „ Bacteriological Examination of Water for Cholera Bacilli 553 7 PAGE Ducrey, A. — Cultivation of Leprosy Bacillus 553 Gebiiard, C. — Cultivating Gonococcus 553 Freudenreicii, E. de — Permeability of the Cliamberland Filter to Bacteria . . . . 554 Drossbach, P., & K. Holten — Plate Method for cultivating Micro-organisms in Fluid Media 554 Ciiamberland, Ch., & E. Fernbach — Action of Disinfectants on dry and wet germs 555 Ivamen, L. — Method of using Thor Stenbeck’s Centifuge for detecting Tubercle Bacilli 556 Giltay, E., & J. II. Aberson — Method for Testing Filtering Apparatus (Fig. 83) . . 556 (2) Preparing Objects. Longhi, P. — Eserin in Protistological Technique 558 Heinricher, E. — Preserving Achlorophyllous Phanerogamous Parasites and Sapro- phytes 558 Bieliajew, W. — Preparation of Vegetable Objects 558 Klercker, J. af — Isolation of Living Protoplasts 558 Chapeaux, M. — Histological Observations on Hydromedusse 559 Schottlaender, J. — Graafian Follicle 559 Gage, S. H. — Methods of Decalcification 559 (3) Cutting, including Imbedding and Microtomes. Reichert’s Microtomes with Oblique Planes (Figs. 84 and 85) 560 (4) Staining and Injecting. Rhumbler, L. — Double- Staining for Distinguishing Living and Dead Substances after their Preservation 562 Klercker, J. af — Staining of Protoplasts and Cell-wall 562 Ssudakewitsch, J. — Metachromatism of Parasitic Sporozoa and Carcinoma Cells . . 563 Torok, L. — Protozooid Appearances in Carcinoma and Paget's Disease 563 Ohlmacher, A. P. — Safranin Nuclear Reaction and its Relation to Carcinoma Coccidia 564 Thanhoffer, L. v. — Nerve-endings in Muscle 564 Bristol, C. L. — Restoration of Osmic Acid Solutions 564 Gage, S. H. — Trustworthy Solution of Hsematoxylin 564 Mangin, L. — Ruthenium-red as a Staining Reagent 565 Nicolle, M., & J. Cantazucene — Staining Properties of Oxychloride of Ammonia- cal Ruthenium 565 Kultschitzky, N. — A new Staining Method for Neuroglia 565 Solles — Negative Staining Method for Finding Tubercle Bacilli 566 (5) Mounting, including Slides, Preservative Fluids, &c. Julien, A. A. — Mounting Medium for Algse and Fungi 566 „ ,, Spiral Springs for Manipulating Cover-glass Preparations .. .. 566 Schenck, H. — Mounting large Sections of Vegetable Preparations 567 Julien, A. A. — Balsam-paraffin for Cells .. 567 Moore, Veranus A. — Apparatus for Holding Cover-glasses (Fig. 86-88) .. .. 567 (6) Miscellaneous. Noll, F. — Demonstration of Heliotropism 569 „ „ Demonstrating the Pigment of the Floridese 569 Molisch, H. — Detection of “ Masked Iron ” in Plants 570 Proceedings of the Society: — Meeting, 21st June, 1893 571 8 Becks Microscopes, FIRST CLASS OBJECT GLASSES. MICROTOMES. LAMPS. OBJECTS. CABINETS. APPARATUS. WITH PERFECT FINE ADJUSTMENT, EVERY LATEST IMPROVEMENT, AND EACH SUPPLIED WITH AN IRIS DIAPHRAGM. FULL ILLUSTRATED DESCRIPTIVE CATALOGUE FREE ON APPLICATION. No. 25. New Form CONTINENTAL MODEL MICROSCOPE. R. & J. BECK, 68 Cornhill, London, E.C. FACTORY: LISTER WORKS, KENTISH TOWN, 9 THE CAMBRIDGE SCIENTIFIC INSTRUMENT COMPANY, ST. TIBB’S ROW, CAMBRIDGE. Full Particulars of this and other Section Cutting Appliances will be found given in Section 20— H I STOLOG Y, pp. 66-71, of our ILLUSTRATED DESCRIPTIVE LIST, which will be sent to any Address in the Postal Union on receipt of Is. 6d. ADDRESS ALL COMMUNICATIONS- INSTRUMENT COMPANY, CAMBRIDGE. ORIENTATING APPARATUS, Or ADJUSTABLE OBJECT HOLDER (Patent applied for) can now be obtained with the Rocking Microtome. ~D Y means of this Holder the object can be placed in the exact position for cutting sections in the desired plane. It is extremely rigid, and can be adjusted by screw motions so that the object is rotated indepen- dently about a vertical and horizontal axis. The Holder can be adapted to any existing Rocking Microtome ; the rocking arm should be returned for this purpose. The cost will be about 18s. All Rocking Microtomes have now a new and improved method of clamping the Holder to the rocking arm (Patent applied for). It clamps very firmly with a very small movement of the screw, and gives a con- venient rough adjustment of the object towards the razor. It can be adapted to existing Microtomes at a small cost, the rocking arm only being required for adaptation. ROCKING MICROTOME. Price J25 5s. With Orientating Apparatus, Price £6. 10 Or. Henri van Heurcks Microscope FOR HIGH-POWER WORK AND PHOTOMICROGRAPHY, AS MADE BY W. WATSON & SONS TO THE SPECIFICATION OF Dr. VAN HEURCK OF ANTWERP. Pitted with Fine Adjustments of utmost sensitiveness and precision, not liable to derangement by wear. Has Hackwork Draw -tube to adjust Objec- tives to the thickness of Cover Glass. Can be used with either Contir tal or English Objectives. Pine adjustment to Substage. The Stand specially designed to give tho utmost convenience for manipulation. As Figured (but without Center- ing Screws or Divisions to Stage), with 1 Eye-piece .. £18 10s. Also made with Continental form of loot £18 Without Hackwork to Draw-tube £19 Full description of the above instrument, and Illustrated Catalogue of Microscopes and Apr ratus, also classify list of 40,000 Mir-o* scopic Objects warded post free on application to W. Watson & Sons, 313 High Holborn, LONDON, W.C. AND AT 78 Swanston Street, Melbourne, Australia. Awarded 28 GOLD and other Medals at the principal International Exhibitions of the World. JOURNAL OF THE ROYAL MICROSCOPICAL SOCIETY. AUGUST 1893. TRANSACTIONS OF THE SOCIETY. VIII. — Notes on some of the Digestive Processes in Arachnids. By Henry M. Bernard, M.A. Cantab., F.Z.S., from the Huxley Research Laboratory. ( Read 19 th April , 1893.) Plate VI. Observations on the digestive processes of the Arachnids have hitherto, as far as I am aware, been mainly confined to the Araneids. A comparative treatment of the subject suggested itself to me during my researches on the comparative anatomy and morphology of the EXPLANATION OF PLATE VI. Fig. 1. — Two digestive cells of a Chernetid (one only in outline). Beneath, i. e. outside the basement membrane, are seen the vacuolated peritoneal cells. The faecal “ crystals” are seen streaming out into the lumen of the gut between the cells. Fig. 2. — The different stages, as seen under the Microscope, in the reduction of the homogeneous food-globules into the faecal “ crystals.” Fig. 3. — Three digestive cells of Scorpio. The food-globules are being assimi- lated within large vacuoles, there being one vacuole in each cell, The distal end of the cell is a dense cushion of granular staining protoplasm, through which the faecal “ crystals ” pass. The peritoneal cells are filled with food-globules apparently tem- porarily stored up. Here and there these globules are being digested and reduced to “ crystals,” which escape into the blood and are found in the blood-corpuscles. Fig. 4. — A group of digestive cells of Scorpio crowded out of the epithelium, and floating free in the lumen of the gut. The nuclei are completely obscured. Fig. 5. — Part of section of the abdomen of an emaciated house-spider ; small parts of four digesting diverticula are seen ; the faecal crystals are massed close to the basement membrane. Two fragments of Malpighian tubules are seen running through the highly vacuolated peritoneal cells; these tubules are crowded with faecal “ crystals.” Fig. 6. — Portion of a longitudinal section of an abdominal diverticulum of a Galeodes grsecus; the epithelium is completely disorganized. A small mass of stained coagulum (containing moth’s scales) riot yet converted into food-globules in the middle. The faecal “crystals” have sunk to the ventral side of the tube. They are seen in a bright yellow fluid, which is the assimilable product of the food- globules. This is also seen dorsally on the outside of the tube, having passed through the basement membrane, to mix with the blood. No trace of a peritoneal layer is visible. Fig. 7. — A group of digesting cells of Galeodes araneoides (?) showing mulberry- like food-masses breaking down into faecal “crystals.” These food-masses have 1893. ' 2 ii 428 Transactions of the Society . Galeodidse. As might he expected in such an unworked field, many points have come to light not only new in themselves, but affording new interpretations of facts well known but incompletely understood. For the sake of clearness, I shall keep the observations on each group distinct. The Chernetid^. I take these first because, as will be seen from what follows, they are in many respects the least specialized. The specimens examined were Obisium museorum and 0. cancroides, kindly given me by Dr. Gunther, F.B.S. The digesting cell of Obisium is a large lobate body, so filled with food-globules that the nucleus is quite obscured (fig. 1). I have not been able to follow the conversion of the food, which in the sections looks like a granulated coagulum lying in the lumen of the gut, into the clear, homogeneous food-globules within the cells. The importance of commencing with the Chernetidae lies in the fact that the homogeneous spherules in the mid-gut cells of these animals are at once recognizable as food-globules, and not as the secretions of gland-cells. In the Araneids, on the other hand, this point is not so evident. The long, thin tubules branching from the gut in these latter animals are more like glands than digesting diverticula, and they have almost universally been considered as such. There was, therefore, every excuse for those who examined these gland-like diverticula when they imagined that the contents of the cells were secretions which were to be poured into the gut for the digestion of the food. It is true that Bertkau found that food sucked in found its way to the tips of these diverticula, but that fact alone was hardly sufficient to lead him to recognize the refrac- tive globules in the cells as ingested food. Had he begun with any of the Chernetidae, as I was fortunate enough to do, he would at once have recognized this fact, because in these Arachnids it is quite impossible to mistake the mid-gut diverticula for glands of any kind ; they are simple distensions, often very shallow, of the digestive tube. While, therefore, the observations of Plateau * and Bertkau t dropped out of some of the vacuoles in the process of section-cutting. The protoplasm of the cell is much vacuolated. A tracheal tube runs through the peritoneal cells. Fig. 8. — A group of vacuolated digesting cells of Ehax, there being no food- globules in the vacuoles. The whole digestive system is empty, excepting that here and there groups of faecal “crystals” occur, the remains of a previous meal, which have failed to tind their way out into the central canal. * “ Eecherches sur la structure de l’appareil digestif et sur les phenomenes de la digestion chez les Araneides dipneumones.’ In three parts. Bull. Ac. R. Bruxelles, xliv. (1877). f “Uber den Bau u. die Function der sog. Leber bei den Spinnen,” Arch. f. Mikr. Anat., xxiii. (1884). Digestive Processes in Arachnids . By II. M. Bernard. 429 retain their value as records of facts, they require re-stating from this new point of view, viz. the contents of the so-called liver-cells are not products of secretion, but food in various stages of digestion. It is worth noting that these food-globules are quite indistinguish- able from those found in Amoebae, which have the appearance of oil-drops. In neither case, however, do they consist of pure fat. The food-globules in the digesting cells of Araneids, according to Bertkau, do not darken under the action of osmic acid more deeply than the other parts of the cells. They do not dissolve in ether, and are easily dissolvable in glycerin and water. In the process of assimilation, these homogeneous globules become first finely and then coarsely granular, and are gradually transformed into groups of small refractive bodies which look black by transmitted, but white by reflected light (fig. 2). If the food-globule is small, one single crystal-like body is all that is left. * These so-called “ crystals ” are either rhomboidal, or rod -like, or they may have no definite form. This breaking-down of the food-globules is clearly indicated in Bertkau’s drawings. Following these crystal-like residual bodies further, we find that they are gradually excreted at the sides of the cells (fig. 1), and that here they slowly collect, to be discharged in a stream into the lumen of the gut, where they mix with the raw food not yet taken up by the digesting cells and converted into the fat-like food-globules. From end to end of the digesting portion of the canal, these small faecal bodies are to be found mixed with the sucked-in food. The separation is effected at the point where the canal suddenly narrows to form the hind-gut. Whether this long coiled tube is morpholo- gically the true hind-gut, I cannot say, but functionally it must be considered as such. At this point the epithelium suddenly changes, and a thick stream of the crystalline bodies is seen leaving the coagulated food in the mid-gut and forming into faecal masses, which are to be found at intervals along the hind-gut as far as the ster- coral pocket. In this pocket a great number of the faecal masses accumulate, being held back for some reason before being finally ejected. A close examination of the contents of the stercoral pocket shows that it consists almost entirely of countless numbers of these minute crystal-like bodies which in the aggregate also look black by trans- mitted light, but are chalky white by reflected light. The only other substance I could find was an occasional food-globule, whose presence is to be accounted for as follows. The digesting cells (as shown in fig. 1) are often distended to such an extent by ingested food that they break down. Here and there, fragments of cells and escaped * Cf. Mr. Moore’s paper on the Amoeba (in Ann. and Mag. Nat. Hist., Feb. 1893), in which he considers the so-called “ crystals ” in these animals to be the irreducible remains of the food-globules. 2 a 2 430 Transactions of the Society. food-spherules are to be met with in the lumen of the tube. Any of these which fail to find their way back again into the digesting cells would be carried on into the hind-gut and so into the stercoral pocket. Comparatively few, however, so escape, as some selective process evidently goes on at the aperture of the hind-gut, otherwise it would be impossible to account for the separation of the faecal “ crystals ” from the coagulum. The epithelium of the hind-gut apparently has no power of dissolving down the food-globules into assimilable fluids. Before escaping into the blood, the assimilable fluids resulting from the dissolution of the food-globules have to pass through a layer of cells which clothes the whole alimentary canal externally. These cells seem to be characteristic of the Arachnids, but are differently developed in different genera. Bertkau has called them the “fat- body ” cells, and suggests that the functions of this “ fat-body ” are probably supplementary to those of the alimentary canal. My own observations tend fully to confirm this latter proposition, viz. that these mesodermal cells, clothing the alimentary canal externally, play a definite, and in some cases a very important role in alimen- tation. But I prefer to use the more indefinite description of these cells as the peritoneal covering of the alimentary canal. In the Ohernetidae, these peritoneal cells are often so vacuolated as almost to appear like a layer of connective tissue with large nuclei suspended on the threads (fig. 1). As far as one can judge by appearances alone, one would say that this is in order to allow the nourishing fluids to flow freely through the wall of the alimentary canal into the blood. In one specimen examined, the animal was infected with bacteria, and it is perhaps significant of the nourishing character of the fluids contained in or passing through these peritoneal cells that the great round nests of bacteria show a decided tendency to form within these cells. To sum up, then, we find that the juices sucked in are turned by the digesting cells of the Ohernetidae into homogeneous globules, in- distinguishable from the so-called fat-globules of Amoebae ; that these are slowly dissolved, leaving small crystalline bodies also indis- tinguishable from the so-called crystals of Amoebae; that these bodies are excreted and eventually found as the chief constituent of the faeces in the stercoral pocket. ScORPIONIDiE. The usual claim that Scorpio has salivary glands is incorrect. The whole of the internal space of the cephalothorax in these animals is so compressed longitudinally that the single pair of cephalothoracic diverticula comes so far forward that it has been mistaken for a salivary gland, whereas serial sections show that it does not differ Digestive Processes in Arachnids. By II. M. Bernard. 431 from the other diverticula. As far as my own researches with the Chernetidae, Scorpionidae, Araneidae, and Galeodidae extend, none of the diverticula of the alimentary canal are specialized into glands ; they are all simple digesting diverticula.* The cells lining the alimentary diverticula of Euscorpio differ from those of the Chernetidae in being somewhat more specialized. They are smaller, and each contains one enormous food-vacuole. Between the food- vacuole and the lumen of the gut, there is a thick layer of staining protoplasm (fig. 3). These cells are sometimes found long and narrow, the food-vacuoles bulging out the individual cells in such a way that in section there is a confused mass of cells out of which it is difficult to make any order. In other places the digesting cells are short and square, and appear to have plenty of room (fig. 3). Within the food- vacuoles, the typical food-globules are found in all stages of disintegration, ending as in the Chernetidae in the same minute crystal-like bodies which, however, tend rather to be long and rod-shaped than rhomboidal. These are excreted, passing lengthwise through the thick cushion of protoplasm at the distal boundary of the cell. Cases can be found in which the cushion has “ crystal ” bodies standing out all over it like the bristles of a hedgehog. This fact led me to see if I could find any case of the discharge of these faecal bodies by the bursting of the vacuoles. I am inclined to think that this does not take place. The “ crystal ” bodies in Amoebae pass directly through the ectosarc, round the outer edge of which they are often found adhering in considerable numbers, and further in the Chernetidae they must pass out directly through the protoplasm of the digestive cells. As in the Chernetidae, these faecal crystals in Scorpio are the chief constituent of the contents of the hind-gut, which, owing to its length, has no need of a stercoral pocket. At the anterior end of the hind-gut, however, one is aware of the presence of large clear bodies mingled with the faeces which give the latter, when viewed by transmitted light, a mottled appearance. On close examination, these are found to be cells, which, owing to the crowding of the digestive cells when their vacuoles are full, had broken away and travelled down the gut. Such detached cells are found in enormous numbers, generally in groups (fig. 4), in all the wider lumina of the alimentary diverticula, and many of them at least, if not all of them, ultimately arrive with the faeces in the hind-gut. During this passage, the gradual digestion of the contents of their vacuoles goes on, and the excretion of the crystalline remains can be seen to take place as in the stationary cells (fig. 4). But what * As such digesting diverticula would naturally give all the reactions of the different secretions necessary to the digestive process, the attempt to show that these diverticula are pancreatic glands by means of chemical reagents cannot be couclusive. Cf. Griffith aud Johnstone, Proc. Roy. Soc. Edinburgh, xv. 432 Transactions of the Society. becomes of these cells ? Advancing further down the hind-gut, they apparently get fewer and fewer, and the faecal masses less and less mottled. It seemed to me unlikely that these living cells should be lost to the body, and I searched diligently to see if I could find any cells passing through the wall of the hind-gut. I found none actually passing through, but what I did find was almost more interesting in its suggestiveness. Between the fecal masses and the wall of the canal, round cells of granular protoplasm with a rather indistinct nucleus were found. These cells appeared in all the sections, some apparently just leaving the fecal masses. There can, I think, be little doubt that these cells belong to the places in the sections where they are found, and have not been swept-in in the processes of cutting and mounting. If so, there can also be little doubt that they are the representatives of the digesting cells which through overcrowding had broken loose and had been carried down into the hind-gut. These round cells within the hind-gut are quite indis- tinguishable from the blood-corpuscles in the blood-plasma outside the gut. W ithout making any positive affirmation, I think that it is highly probable that these digestive cells, instead of being lost to the animal by passing out with the feces, pass through the wall of the gut and function as blood-corpuscles. There seems no reason why this should not take place, although the actual fact would pro- bably be difficult to establish. This is, however, not the only interesting point in the digestion of Euscorpio. The peritoneal cells clothing the whole alimentary canal externally are found to be so full of globules, exactly re- sembling the typical food-globules, that both the nuclei and the cell divisions are entirely obscured. Bertkau found bodies somewhat similar to food-globules in the peritoneal cells of an Araneid ( Atypus ), but said that they differed from the latter in being built up of regular concentric layers, and further in their chemical reactions. While the typical food-globules, according to Bertkau (who, however, did not recognize them as such), are dissolvable in glycerin and water, but indissoluble in ether and alcohol, the bodies in the peritoneal cells resist the action not only of alcohol and ether, but also of water and glycerin. With osmium they are quickly and intensely blackened, and iodine makes them red-brown. Bertkau also found traces of these bodies occurring in the peritoneal layer of Eresus ; indeed there is reason for believing that they are very commonly present in the peritoneal cells of spiders (cf. next section). The homogeneous globules found in the peritoneal cells of Euscorpio show no traces whatever of lamination viewed under the highest power. They are in every respect indistinguishable micro- scopically from the food-globules within the digestive cells. So great is the similarity that it is difficult to believe that bodies so alike, and separated from one another only by the fine basement membrane of the digestive cells can be really different ; indeed, from what follows Digestive Processes in Arachnids. By H. M. Bernard. 433 it will be seen that they are essentially similar. The presence of these food-globules in the peritoneal cells is probably to be attributed to the inability of the digesting cells to hold all the food taken m, which is therefore passed temporarily into the cells outside the alimentary canal as into a kind of storehouse for undigested food. Metschnikoff * has already shown in the Ctenophora that endoderm cells pass on solid particles such as carmine grains to adjacent meso- derm cells. The question, then, naturally arises, if these are food-globules why are they not digested in these cells as they would be in Amoebae ? Examining them carefully to ascertain this point, I was speedily con- vinced that a slight digestive process does go on. Here and there globules are seen no more clear and homogeneous but finely granular ; others are even broken down completely into the typical crystal -like bodies which are apparently the invariable remains of such food- globules when their assimilable elements have been extracted. Com- pared, however, with the immense number of food-globules stored up in these cells, only a very small percentage were being assimilated. When such extra-enteric digestion does take place, the crystalline residue does not pass back into the alimentary canal, but is carried away by the blood-corpuscles (fig. 3). What the ultimate fate of these blood- corpuscles is I have been unable to ascertain. If this description of the phenomena is correct, the life-history of these blood-corpuscles is curious. Originating as digesting cells within the alimentary canal, they break loose and pass down the gut, assimilating the contents of their food-vacuoles during the passage, and finally pass out through the wall of the hind-gut and become free blood-cells. When in the blood, among other functions, we find them carrying away faecal masses from the peritoneal cells which have somewhat irregularly digested the food-globules temporarily stored up in them. I am indebted to my friend Prof. Howes for calling my attention to the somewhat similar observations recorded by Kiikenthal in an Oligochaetan Annelid ( Tubifex ).f Kiikenthal found the lymph cells carrying about brown granules which they obtained from the walls of the dorsal blood-vessel and its branches, which latter surround the alimentary canal in a close network. When full of these brown granules the lymph cells are distinguished by the name of chlora- gogen cells, which seen mussed on the above named blood-vessels form the brown body thought at one time to be the liver. The brown granules undergo a change within the lymph cells ; they are dissolved down into minute dark bodies. These dark bodies are finally got rid of by means of the nephridia, the tubules of which Kiikenthal describes * “ Uber die intracellulare Verdauung bei Codenteraten, Zu l. Anzeig., 1880, p. 261. t “ Uber die lymphoiden Zellen der Anneliden,” Jenaische Zeitschr., xviii. (1885). 434 Transactions of the Society. as being full of them. In the next section, we shall find that in the Araneids the Malpighian tubules are completely filled with faecal “crystals.” We reserve further discussion of this striking parallel until we have described the process in the Araneids. ARANEIDiE. The Araneids are almost the only Arachnids whose digestive processes have been investigated, chiefly by Plateau and Bertkau. The interpretations of the facts described by these writers require, however, to be considerably modified by what we have learnt from Obisium and Scorpio. The contents of the so-called liver cells are not secretions, but food-globules and their crystal-like remains. How near Bertkau came to the recognition of this fact may be gathered from his discovery that the cells lining the caeca took in the carmine granules which he mixed with water and gave the animals to drink. Why then, he asks, should they not also take in “ assimilated nutri- ment ” ? — or, we naturally add, the raw food as food-globules ? The digesting cells do not all appear to have specialized vacuoles as in Euscorpio. Schimkevitch * describes and figures two kinds of cells in Epeira, one kind resembling those of Obisium (fig. 1), and the other resembling the vacuolated cells of Scorpio (fig. 3). It would be interesting to find out in what portions of the gut this specialization of the digesting cells takes place. The food-globules break down into the typical crystals, the latter appearing in two forms, as rather large glassy looking bodies, often rod-shaped, and as very minute bodies, which are found massed in the bases of the cells, giving this part of the cells a brownish appearance. This faecal matter appears to be discharged in two different ways. One portion of it is excreted from the cells into the lumen of the gut, to find its way down the long narrow tubules into the central canal. Another portion appears to pass through the wall of the canal into the peritoneal cells , and from these into the Malpighian tubules, by means of which it finds its way into the stercoral pocket (fig. 5). The evidence for this somewhat remarkable conclusion will be found in what follows. On opening the body of many spiders, e. g. the common garden spider, Epeira diadema, the whole abdominal portion of the alimentary canal, with its ramifying tubules, has a very striking chalky look. In Epeira , the chalk-white shines through those parts of the skin which are free from pigment and gives rise to the white cross and spots which characterize it. Many observers have noticed that this chalky appearance in spiders is due to a layer of fine particles often showing a metallic glitter. There have been many conjectures as to what these particles are. The last conclusion arrived at (by Bertkau) is that the bodies strongly resemble certain constituents of the faeces * “Etudes sur rAnatomie de l’Epeire,” Ann. Sci. Nat., xvii. (1884). Digestive Processes in Arachnids. Bg II. M. Bernard. 435 found in the stercoral pocket, and they give the same chemical reactions ; that they are, in fact, guanin. How does this faecal matter come to be in the peritoneal cells outside the alimentary canal? Two answers to this question are suggested by our observations on Obisium and Scorpio above described. We find in Obisium the digesting cells of the gut crowded from end to end with food-globules (fig. 1), the peritoneal cells adjoining having apparently nothing else to do than to pass on the assimilated fluids. In Scorpio , we have the digesting cells more specialized, each containing a large vacuole capable of reducing only a limited number of these food-globules. A large number of them, therefore, pass out of the endodermal digesting cells into the adjoining meso- dermal cells, probably returning again to be assimilated in the digesting vacuoles. While, however, they are thus stored up, the peritoneal cells occasionally commence to assimilate them for them- selves, reducing them, when they do so, into minute crystal-like bodies, essentially similar to those within the gut. The round globules found by Bertkau in the peritoneal cells of Atypus can, I think, be nothing else than food-globules which have passed through the wall of the gut, probably as into a temporary storehouse. Unfortunately, as none of my preparations of Araneids show any food-globules in the peritoneal cells, I have been unable to ascertain whether they are there subjected to any digestive process. But this is what may take place in the Araneids. Food-globules pass out of the digesting cells into the adjoining mesodermal cells, and may there be, normally or abnormally, digested, the fsecal remains being carried away by the Malpighian tubules. A second method of accounting for these faecal “ crystals ” in the peritoneal cells and the Malpighian tubules is by supposing that the digesting diverticula are so branched and their lumina are so narrow that the faecal masses resulting from digestion within the more distal portions of these tubules fail to find their way into the central canal, and have to he got rid of by passing through the wall of the gut and into the Malpighian tubules. The difficulty of getting rid of faeces from the digestive tubules has indeed already been suggested as an objection to the supposition that the so-called “ liver” diverticula might he digesting, and not secreting, organs. It is obvious that this difficulty could be got over if the faecal “crystals,” or at least a portion of them, could pass out of the gut and be discharged through the Malpighian tubules. Fig. 5 represents part of a section of the abdomen of an emaciated house-spider caught in mid-winter. It represents parts of four digesting diverticula, between which are seen the peritoneal cells, which in this case were highly vacuolated, the nuclei being suspended on threads, and portions of two Malpighian tubules. The digesting cells contain round granules which I take to be food-globules, though 436 Transactions of the Society. they are deeply stained. The faecal crystals are seen here and there travelling up into the lumen of the gut from between the cells. But by far the greater number of the crystals were massed along the bases of the cells, just inside the basement membrane, giving a brown appearance to the basal half of the digesting epithelium.* No food- globules could be found anywhere among the peritoneal cells. The Malpighian tubules, however, were full of faecal “ crystals.” Where did they come from ? Close examination showed them suspended here and there on the protoplasmic strands of the peritoneal cells, apparently on their way from the digesting diverticula to the Malpighian tubules. We have here, then, a case of a fasting spider with no surplus food-globules stored up in the peritoneal cells, and yet an immense number of faecal “ crystals ” in the Malpighian tubules. I can only suggest that these faecal “ crystals” came from the basal ends of the digesting cells, this being no more difficult to believe than that food- globules or carmine-grains pass out from the endodermal into the mesodermal cells. With regard to these two explanations of the presence of this guanin in the peritoneal cells, I do not see why both of them should not be correct. We know that bodies strongly resembling food-glo- bules are found in the peritoneal cells of the Spiders, and we know from Euscorpio that such bodies may undergo a process of digestion in these cells. But unless the digestion of food-globules in the peri- toneal cells is more frequent in the spiders than it apparently is in Euscorpio, it would hardly account for the enormous number of faecal “ crystals ” found in their peritoneal cells and Malpighian tubules. I therefore think that we must look for the main supply of these bodies to the digesting tubules themselves in the manner above described. I am inclined to think that a certain number of the faecal “ crystals ” in the digesting cells are broken down into smaller bodies, able to pass easily through the wall of the gut, or else that the smaller bodies are selected for this purpose, while the larger, or those not broken down, are excreted into the lumen of the gut. The bodies which find their way into the Malpighian tubules seem to be ground down to form the minute round bodies found in the stercoral pocket, wdiich differ from those forming the faecal masses, and which Plateau has traced to the Malpighian tubules. In putting forward this explanation of the phenomenon, I do not lose sight of the fact that these crystal-like bodies in the peritoneal cells and the Malpighian tubules of Araneids may be some form of normal waste product, some compound of urea, presenting a close resemblance to the faecal “ crystals ” which result from the digestion of the food-globules within the gut. So far, however, we have no * Cf. Bertkau’s figures (tom. cit., p. 428), where he shows the crystalline contents of the cells collected chiefly at their bases. Digestive Processes in Arachnids. By H. M. Bernard. 437 evidence of sucli an interpretation, while on the other hand there is a certain amount of evidence in favour of the view put forward in this paper. We have, further, some indirect evidence against the supposi- tion that this peritoneal faecal matter results from normal waste. Garrod’s * researches tend to show, in Vertebrates at least, that urates in the blood and tissues are derived either directly from the food, if it happens to contain urea, or by absorption from the kidneys where it is normally formed. Assuming that the same law applies to the Arachnida, it is hardly likely that these crystal-like masses in the peritoneal cells of spiders are due to the presence of uric acid in their food, as we find no trace of such substance in the peritoneal cells of the Chernetidas and Galeodidae, whose food very much resembles that of the Spiders.! Further, I think it highly improbable that this substance is formed in the cells of the Malpighian tubules partly to be discharged into the stercoral pocket, and partly to be absorbed by the surrounding tissues. The Malpighian tubules, of no other Arach- nids, produce such bodies. Plateau distinctly calls attention to the fact that there is “ no guanin in the products of the Malpighian tubules of Phalangids, so characteristic of the urinary secretions of Araneids.” | The Malpighian tubules of Euscorjpio and of Galeodes are searched in vain for any such substance, while Obisium has no Malpighian tubules. Again, the arrangement of the Malpighian tubules in the Araneids seems to be unique among the Arachnids. Instead of being bathed by the body fluid, they form, with the peritoneal cells and the digesting tubules, a compact mass. In fig. 5, and again even more clearly in Bertkau’s figure, § the Malpighian tubules are seen to be completely embedded in the peritoneal cells. This seems to imply a close physiological connection between these tubules and the peritoneal cells, which latter we have seen are in close physiological connection with the alimentary canal. Indeed, it seems to me not altogether improbable that in the Araneids, which are the only Arachnids whose spinning glands are always functional, and presumably always carrying away waste products, the Malpighian tubules may have become specialized for the purpose here described, viz. of removing faecal matter from the peritoneal cells. Further, a point of some significance deserves mention. The greater part of the chalky matter, in the peritoneal cells, is found at the periphery of the com- pact mass formed by the digesting tubules. This is where we should naturally expect to find it, because it is most difficult to get rid of the faeces from the blind ends of the tubules. The essential similarity between this chalky-looking matter in the peritoneal cells and the * “ On the Place of Origin of Uric Acid in the Animal Body,” Proc. Roy. Soc., xl. (1886) p. 484. f It deserves mentioning, however, that the food of spiders may be mixed with the secretions of their own poison-glands. X Tom. eit., p. 441 (p. 75o). § Tom. cit., p. 428 (plate xii. fig. 4). 438 Transactions of the Society. matter within the blind ends of the tubules was clearly recognized by Plateau,* who, however, thought that it was some fatty substance. The fact that the granular contents of the Malpighian tubules looks white by reflected light, and black by transmitted light, has been further recorded by Bertkau. Taking, then, further into consideration this very close resem- blance between the chalky substance in the peritoneal cells and Malpighian tubules of Araneids and the undoubted faecal crystals within the gut and stercoral pockets of the Arachnids, I think there is a considerable weight of evidence in favour of the interpretation of the phenomena here suggested. The above-mentioned cases of extra-enteric digestion make it not impossible that the processes described by Ktikenthal, and above referred to (p. 433), may admit of a similar interpretation. It is to be specially noted that the brown bodies taken up by the lymph cells appear on the dorsal vessel and its branches, which are directly related to the mid-gut. As the contents of these vessels would be largely derived from the products of enteric digestion, it seems more probable that these brown bodies are food-products than waste products. We have, further, the fact that these brown bodies undergo a change within the lymph cells very much resembling the change undergone by the food-globules when assimilated. 1 have examined the chloragogen cells of Lumlricus with an apochromatic oil- immersion lens (Zeiss), and though I could not find any of the brown globules being dissolved down into black bodies as Ktikenthal describes, yet microscopically the brown bodies themselves were quite indistinguish- able from the typical food-globules so often alluded to above. The suggestion that the function of the chloragogen cells is digestive is not new. I think, however, that the observations here described justify me in repeating the suggestion. There is nothing new in principle in these cases of digestion by mesodermal cells. Although the undoubted rule among the Metazoa is that the endoderm cells, even from the first digestion of yolk in the embryo, undertake the processes of digestion, we have records of digestion both by ectoderm and by mesoderm cells. There is no claim here put forward of mesoderm cells becoming specialized for digestion, at least in the Arachnids, but only that mesoderm cells occasionally digest food stored up in them, therein simply reviving the power once possessed by their Protozoan ancestors, and still possessed by their free phagocyte brethren. For the purposes of this paper some young spiders, just hatched and clinging helplessly to the nest, were examined. These, when seen entire, cleared in cedar or clove oil, show the digesting diverticula * Tom. cit., p. 428 (p. 344 : “ Chez tous les Epeires la glande est granitee de blanc ou de blanchatre a la surface, fait du a la presence vers le sommet des ccecums supcrficiels d’une accumulation de graisse incoloree finement divisee. II arrive parfois que cette (jraisse remplit entierement les ccecums de la surfacc,>). Digestive Processes in Arachnids. By II. M. Bernard. 439 very marked and regular in the cephalothorax, but as a confused mass in the abdomen ; in both cases they were black or mottled. Sections show that this black colour is due to accumulations of the minute crystal-like bodies with which we are now familiar, but which must, in this case, he due to the reduction of yolk, as the animals had certainly not taken in any extraneous food. This is very suggestive when taken in connection with the great resemblance under the Microscope between the food-globules and yolk-granules. The fact that the digestion of the yolk-granules in these Arachnids leaves as a residue the typical faecal “ crystals ” of ordinary enteric (intracellular) digestion of food-globules, may throw some light upon the nature of the yolk. May it not be possible that the yolk is in this case un- assimilated food, such as in Euscorpio passes out of the digesting cells to form the stored up food-globules in the peritoneal cells, and in Tubifex probably forms the brown bodies on the walls of the dorsal blood-vessels, which bodies are taken up, and apparently assimilated, by the chloragogen cells ? It would be interesting to know whether these faecal “ crystals ” always result from the assimilation of yolk. Galeodim. The Galeodidae agree with the Araneids in having no long hind- gut such as we find in the Chernetidae and the Scorpionidae. The diverticula open into a central canal, which again opens into a hind- gut specialized into a stercoral pocket. As in Scorpio, the digesting cells are of all shapes, according to the space they have for their development. That there is no specialization of the epithelium lining the diverticula in Galeodes has lately been pointed out by Birula,* who shows that the cells throughout the whole intestinal canal are of essentially the same character. They are sometimes long, and almost thread-like, preserving, however, their character throughout. The peritoneal cells are very unevenly developed, sometimes quite undemonstrable. One specimen examined ( Galeodes grsecus , kindly sent me by Prof. Mobius) had been killed immediately after a good meal; its abdomen was so swelled up that I had taken it for a pregnant female. The abdominal diverticula and even the central canal were surcharged with coagulum, and a wonderful confusion reigned. The epithelium was completely disorganized, and the tubes were distended by an amorphous mass of coagulum, food- globules, faecal “crystals,” and here and there moth’s scales, or feathers (fig. 6). I was quite prepared for the breaking off of the distal ends of the digesting cells when overloaded with food-globules, but the complete disintegration of the whole epithelium I did not expect, and could hardly believe, in spite of my inability, after prolonged searching, * “ Der Mitteldarm der Galeodiden,” Biol. Centralbl., xi. p. 295. 440 Transactions of the Society. to find any trace of cell-divisions. I was eventually quite convinced that the cells were mixed in a confused mass with the contents of the tubes, to form what is practically nothing else than a living digesting fluid, by finding that most of the tubes were lined along their inner ventral sides by a thick layer of faecal “ crystals ” (fig. 6). The most likely explanation for this fact seems to be that the “ crystals ” are formed by the cells floating in this fluid, and then sink under the action of gravity. The epithelium lining the central canal had also completely dis- appeared into the mass of coagulum which distended it. In the diverticula the lumen is comparatively small, but in the central canal the lumen is in some parts large, and the epithelium, compared with the size of the lumen, very insignificant. The entire absence of the epithelium, in specimens otherwise not badly preserved, can only be accounted for by its complete disintegration, the cells wandering into the mass of food. Whether the cells thus mixed up like free amoebae in the coagulum in the gut find their way back again to the basement membrane to re-form the epithelium, I cannot say. It is unlikely that these living cells should be lost to the animal. Their nuclei may pass out through the walls of the stercoral pocket to function as blood-corpuscles, as I believe to take place in Scorpio. If so, the regeneration of the epithelium from the stripped basement membrane would form a most interesting object for research. On dissecting another specimen of Galeodes grsecus , I found many of the liver diverticula soft and blackish brown ; they would hardly stand the touch of the needle without breaking down into a brown powdery substance ; others, again, in the same animal were firm and white like the other healthy tissues of the body. This difference may perhaps he explained by assuming that in the latter cases the epithelia were in the normal condition, while in the former they were disin- tegrated. In the sections above described I found for the first time the assimilable products of the decomposition of the food-globules. It is seen as a highly refractive yellow coagulum within the tubules and in thick layers on their outer surfaces. In fig. 6 there is a mass of it within the tube immediately above the collection of faecal “ crystals,” and further, an accumulation of it outside the gut on its dorsal surface. As above-mentioned, the short hind-gut is enlarged into a great stercoral pocket. The area of the extremely thin wall of this recep- tacle for the faeces is further enlarged by being folded. Under a low power the wall looks thick, which appearance is due to a close pleating of the membrane. Between the pleats on the inner side of the membrane, are found strands of faecal matter, out of which the still serviceable fluids are being extracted. Between the same pleats, but on the outside, are strands of the same yellow substance which has Digestive Processes in Arachnids. By II. M. Bernard. 441 just been mentioned as the final product of the digestion of the food- globules. In another specimen of Galeodes (probably G. Araneoides ) the food-globules were found to be no longer homogeneous globules like fat-drops, but mulberry-like, i. e. composed of a compact round or oval mass of granules, which, unlike the typical food-globules, were stainable with hmmatoxylin (fig. 7). I can only account for this by assuming that there was some change in the diet. It looked almost as if the blood coagulum might have been taken into the cells as it was, without being converted into the typical form. These staining food masses were slowly disintegrated, passing through a stage which resembled the typical food-globule, but was slightly greenish yellow ; these were slowly broken down till nothing but the typical crystal- like bodies remained. These, as usual, were excreted either at the tips or at the sides of the cells, according to the position of the mass of food in the cell. In this case, there was a distinct tendency of the cells to form vacuoles in which these mulberry -like bodies were dissolved. The protoplasm between these mulberry masses was so vacuolated as to have a frothy look (fig. 7). I am inclined to think that these mulberry masses are rather unusual, and that this reticu- lated frothy appearance represents the normal structure of the cells, and indicates the usual size of the food-globules. In this specimen I found clear traces of the re-ingulfing by the cells of the central canal of the food-masses which had broken away from other digesting cells. How easily these mulberry-like masses break loose can be judged from fig. 7, which shows one such held in by a very thin layer of protoplasm. Both the central canal and the stercoral pocket were tilled with these detached food-masses. The last case which requires description is that of a species of Rhax. The digesting cells show no trace of food at all. They are, however, not shrunk together, but maintain very nearly the same shape they would have if filled with food-globules. This, of course, is only possible by the persistence of the vacuoles in which the food had been digested. We therefore find the cells composed of a reticulum of protoplasmic strands in the meshes of which the food globules are usually dissolved. They stand up from the basement membrane like sponges, fig. 8. I am inclined to think that this may explain the reticular structure of the internal protoplasm of many infusoria, which, without such an arrangement, would have to vary in size according to the amount of food ingulfed, whereas we know that the external layers are often far too specialized to allow of any such variations. Phalangiid^. The digestive processes of this group have been worked out by Plateau,* but naturally from the old point of view, that the digesting * “Notes sur les phenomenes de la digestion chez les Phalangides,” Bull. Acad. Belg., xlii. (1870) pp. 710-54. 442 Transactions of the Society. diverticula are hepatic or pancreatic glands, and the contents of their epithelial cells secretions. One of the more interesting facts recorded by Plateau relates to the detachment of a great number of the epithelial cells which float off into the lumen of the gut ; their contents, according to Plateau’s figures, are similar to those of detached or stationary digesting cells of other Arachnids, viz. round homo- geneous globules, which can hardly fail to be food-globules, and minute black points, which are doubtless the faecal “ crystals ” so often men- tioned above. It would be interesting to investigate the fate of these detached cells in the Phalangiidae, to see whether they offer any sup- port to my suggestion that in Scorpio they become blood-corpuscles. It should not, however, be forgotten that the Phalangiidae have a rich system of tracheal respiratory tubes, and that consequently the circu- latory blood system is not so highly developed as in Scorpio with its respiration localized in the lung-books. In both these Arachnids, Scorpio and Phalangium, I attribute the detaching of the cells to the fact that they are digesting cells, a certain number of which, when they are all distended with food- globules, are crowded out. The storing up of the food-globules in the peritoneal layer observed in Scorpio and the Araneids, may be but a further attempt to obtain relief from this excessive crowding of the distended cells. Plateau’s drawings of the peritoneal cells of Phalan- gium (his “ fat-body ”) seem to indicate that they are full of round granules which may perhaps represent stored-up food-globules. Acarid^i. I have only examined sections of Tetranychus tiliarum, which undoubtedly feeds on vegetable juices. Its hind-gut was full of the typical “ crystals ” which seem invariably to result from the assimila- tion of protoplasmic compounds. I could make nothing of the digestive cells themselves. I learn, however, from Mr. Michael, that it is not uncommon to find great accumulations of white chalky matter either being slowly got rid of, or else permanently located in the body-cavities of certain mites. That this chalky matter is similar to the chalky matter in the peritoneal cells of Araneids and also to a small extent in the peritoneal cells and blood-corpuscles of Scorpio seems to me very probable. Some further light is perhaps thrown on this phenomenon by the fact, for which I am also indebted to Mr. Michael, that the digesting cells in Acarines are often found detached from the epithelium. This suggests the overcrowding of the cells with food, and might also imply the storing up of food-globules in mesodermal cells, the diges- tion of which would account for the chalky matter. We can only hope that Mr. Michael will shortly publish an account of his extremely interesting observations on this subject. Digestive Processes in Arachnids. By II. M. Bernard. 443 We have, then, in the foregoing pages, examined some of the digestive processes, as revealed under the Microscope, in the Chernetidae, the Scorpionidae, the Araneidae, and the Galeodidae, and, very cur- sorily, of the Phalangiidae and the Acaridae, and found that in all cases the process is essentially the same. We find that the so-called “liver” is no true liver, but merely a tubular enlargement of the digestive surface. We have further found in Scorpio, traces of extra- enteric digestion in the mesodermal cells surrounding the alimentary canal, and that this process probably occurs in the Araneids also, where the Malpighian tubules are utilized to remove the faecal remains, which however are found in such quantities in the peritoneal cells that we are driven to the conclusion that the greater portion of them are derived directly from the digestive tubules. While, lastly, in some Acarines, chalky matter is found in the body-cavity, which the animals are unable to get rid of at all. This physiological resemblance between the Acarines and the Araneids is interesting in connection with the morphological evidence of their affinities.* The only important Arachnids which we have not examined are the Phrynidae and the Tely phonic! ae, which are so clearly related to the Scorpionidae that we are perhaps justified for the present in assuming that their digestive processes would not differ in essentials from what we have described. These animals would, however, probably repay examination, as nothing can be more instructive than the study of slight variations in details. It is only by this comparative method of research that we can gain any true insight into the vital processes of animal life. * ‘ Some Observations on the Relation of the Acaridae to the Arachnida,” Linn. Soc. Journ. Zool., xxiv. 444 Transactions of the Society. IX. — On Floscularia pelagica sp. n., and Notes on several other Rotifers. By Charles F. Bousselet, F.R.M.S. {Read June 21 st, 1893.) Plate VII. When Dr. Hudson established the Botatorian order of Rhizota (tlie rooted, fixed when adult) it seemed to be such a well-defined group, with all its members permanently fixed to plants or submerged objects, except Conochilus Volvox , in which the animals of the colony are attached to each other in a common gelatinous envelope, and excepting also the very aberrant genus Trochosphsera. But before having completed his great work, Dr. Hudson had to describe a Conochilus ( C . dossuaris) not fixed, nor aggregated together in colonies, but swimming about solitarily in his tube, and a free-swimming Floscule (F. mutabilis) which he called at the time “ a horror to every classifier.” Since then, Mr. Western has found a free-swimming Lacinularia, and Surgeon Gunson Thorpe, R.N., has just described a free-swimming Megalotrocha and another free Lacinularia , so that both families of the Rhizota furnish us at present with examples of animals that are not rooted or fixed when adult. To these I have now to add another Floscule having a corona of vibratile cilia in addition to five tufts of stiff setae, and living in the open waters of lakes, which is as much a free swimmer as the Asplanchnae, Anuraeae, and Polyarthrae, amongst which it sails steadily and deliberately, carrying its narrow gelatinous tube with it. Floscularia pelagica sp. n. PI. VII. fig. 1. Specific characters : Corona circular without any lobes, furnished with a wreath of vibratile cilia ; within this five fleshy prominences with short, stiff, radiating setae ; free- swimming ; eyes absent in adult ; gelatinous case hyaline, very narrow and elongated. EXPLANATION OF PLATE VII. Fig. 1 a.— Floscularia 'pelagica, in tube, ventral view. „ lb. „ corona. „ 1 c. „ dorso-ventral optical section through anterior part of body, a, dorsal antenna. „ 1 d. „ male. „ 2 a. — Colurus cristatus, dorsal view. „ 2 b. „ side view. ,, 3 a. — Notops pygmeeus, side view. „ 3 b. „ dorsal view. „ 3 c. „ jaws, front view. „ 3 d. „ jaws, side view. „ 4 a. — CEcistes brevis , ventral view. „ 4 b. „ anterior part of body, side view. 445 Floscnlaria pelagica, &c. By C. F. Bousselet. I found this remarkable little animal in the small lake on Keston Common, which derives its clear water from Caesar’s Well, a few hun- dred yards further on, in company with A. yriodonta and other free- swimming Rotifers. I collected only from one spot, near the surface of the water, taking no weeds at all from the lake, which is fairly deep, and found about twenty specimens in the single bottle I filled. This, then, is a thoroughly free-swimming Floscule, quite at home in the open water, propelling itself slowly by means of a wreath of vibratile cilia, just like the Ploima, but instead of being driven for- ward, it invariably swims backwards, and looks then like a long, narrow, sternwheel boat, except that the wheel is at the head. The whole body and the gelatinous case are white, of glassy transparency, which is an additional character of pelagic animals. Its nearest ally is Floscularia mutabilis of Hudson, from which it differs in many particulars, as will be seen by the specific characters, and from the description. The animal as a whole is greatly elongated and very narrow, measuring 1/85 in. to 1/65 in. from head to end of foot, and not more than 1 /450 in. at the widest part of the body. The foot when extended is generally one and a half to twice as long as the body, but of course it can contract, and is then more or less reduced in length. The corona, fig. 1 b, is circular without any lobes, and fringed all round with a wreath of fairly long lashing cilia, by means of which the animal swims slowly through the water. The characteristic stiff setae of Floscules are not apparent at first ; they are seated on five fleshy prominences, one of which is dorsal, within the ciliary wreath, and in a direction at right angles to, and across the coronal cup. The animal has the habit of sometimes contracting the lower part of the cup, by which action the rim of the cup becomes slightly everted, and the setae stand out, slanting upwards, and are then visible above the corona. The setae are short, only reaching three-quarters across the corona ; the dorsal prominence and setae are slightly larger than the others. Two small white globules near the rim of the dorsal side of the corona I at first thought might represent the eyes, but 1 found a number of very similar globules on various parts of the corona. A very small dorsal antenna is situated on a pimple about midway on the dorsal side of the coronal cup, as shown in fig. 1 c, a. The lateral canals and vibratile tags are present, but 1 could not find the contractile vesicle. In other respects the anatomy of the animal is exactly like that of other Floscules ; at the bottom of the coronal cup is the usual semi- circular band of very fine vibratile cilia, bounded at each end by a knob bearing a bundle of larger flagella ; then comes the diaphragm, with the buccal orifice, and the undulating elastic tube hanging down into the crop ; the jaws have two teeth as usual. Eight narrow muscular bands run from the rim of the corona to the tip of the foot. The foot is smooth when extended, hut transversely wrinkled 2 i 2 446 Transactions of the Society. when contracted, and has an opening at the tip, from which, I think, the secretion forming the tube is extruded. The animal can contract wholly within its tube, but expands again very readily. The eggs, one to five in number, are carried in a cluster, round the middle of the foot ; in mature ova, two pale red eyes can be seen. The male eggs are only slightly smaller than the female eggs. I saw a young male born ; it is of usual shape, with two red eyes, fig. 1 d. The sheath, as will be seen in the figure, is very narrow, extending some distance beyond the foot, and ending in a cone, and so trans- parent that it is absolutely invisible by transmitted light, but becomes evident by dark ground illumination. Length of animal 1/85 to 1/65 in.; width 1/450 in. Habitat: clear lake on Keston Common. Colurus cristatus sp. n. PI. VII. fig. 2. This very peculiar Rotifer has been found in America by Mrs. Pell, who sent me the sketch and short description from which this account is taken. The lorica, seen dorsally, is ovate, low in front, and very high and arched at the back ; ventrally it is slightly concave. From the middle line of the anterior dorsal edge of the lorica proceeds a long, stiff, pointed, hyaline crest, slightly milled at the edge, which gives a very peculiar appearance to the animal. The head is square, and has the usual frontal plate, appearing like a hook from side view. Two colourless eyes are situated wide apart on the anterior margin of the head. The foot is long, three-jointed, the third joint being the longest, ending in two long, pointed, slightly recurved toes. The internal organs appeared to be normal, but the lorica was so stippled that it was not possible to see much through it. Length 1/50 in. ; width 1/60 in. ; length of crest 1/60 in. Habitat: Highland Falls, New York. Notops pygmseus Caiman. PI. VII. fig. 3. This minute but handsomely coloured rotifer* was found, in the summer of 1891, in the domestic water supply of Dundee, by Mr. John Hood, who sent it at the time to his numerous corre- spondents. It first appeared very sparingly, but from May to October of 1892 it was very abundant, as it is again at the present moment. Mr. Hood had named it Nctops ruber , but delayed too long publishing his discovery, and so when a paper of his to the R.M.S. was * In order to give an idea of the appearance in life of this rotifer, students are advised to colour fig. 3 a either with water colours or crayons as follows: — First colour the large oil-globules orange ; then the larger central division of the stomach marked b blue; then the three smaller divisions g g yellowish green; and the whole remaining parts, except the brain, a light red ; and, finally, the eye crimson with red ink. 447 Floscularia pelagica, &c. By C. F. Bousselet. announced at the November meeting, it was found that an account of it had just been published by Mr. W. T. Caiman,* giving it the above name. A second account has since been published by Dr. 0. Zacharias,t who found this same rotifer in 1892 as a pelagic inhabitant of the large freshwater lake of Plon, in Holstein. Dr. Zacharias has named it Eudsonella pida , but it is so very closely allied to some other Eotifers of the genus Notops , that it cannot very well be separated without at the same time removing several other species of this genus. No doubt the genus Notops needs revision. Notops Brachionus and davulatus are illoricate animals and have one type of jaws, and Notops hyptopus, minor and pygmseus have quite another type of jaws and are loricate. But in order to avoid multiplying synonyms, I will in this paper describe the animal under the name it has first received. The two published accounts and figures hardly do justice to the peculiarities of this remarkable rotifer, and are incorrect in some particulars. I have had a good opportunity of studying it, and so hope to be able to give a fairly complete description, although, owing to its minute size, it has proved an unusually difficult object. Notops pygmseus most nearly resembles Notops minor in shape and in having a decided chitinous lorica ; the foot protrudes from a circular opening in the lorica high up on the ventral side. Its greatest peculiarity are the rich and vivid hues with which the various parts of the body are coloured : the stomach is deep blue and green, interspersed with orange-coloured oil-globules, while the whole of the hypodermis or protoplasmic layer lining the shell, and the other organs except the brain, are of a rich rose red. The shell itself is colourless (contrary to the statements of Caiman and Zacharias), very thin and hyaline, as can be seen by squeezing out the animal. In form the lorica is broadly oval with a wide neck, the edge of which is broadly scalloped ; it is greatly compressed laterally, and in addition pinched in along the dorsal side. The foot is long, cylindrical, without a joint, and wholly retractile within the lorica, in which position it is usually carried ; it terminates in a very small toe. Some friends think they have seen two toes, but with the best optical means I have only been able to make out one ; if there are two, they are very rarely separated. The corona is broadly truncate and bears long vibratile cilia in tufts, by means of which the animal swims in a wobbling manner, revolving at the same time on its longer axis. The whole of the head and corona can be retracted within the lorica by means of two pairs of narrow, transversely striated muscles, attached to the sides of the shell. The mastax is of unusual form and presents some unique * W. T. Caiman, “ On Certain New and Eare Eotifers from Forfarshire,” Ann. of Scott. Nat. Hist., 1892, pp. 240-5. f Forscliungsberichte aus der Biologischen Station zu Plon, i. (1893) pp. 25-6. 448 Transactions of the Society. peculiarities. Its position is upside down, as it were, with the biting parts of the trophi directed downwards and inwards ; a long thin- walled, chitinous tube connects the mouth opening on the ciliary wreath with the lower part of the mastax, and small particles of food were seen gliding down this tube to the jaws. This arrangement is quite unknown in any other rotifer. The trophi are shown in fig. 3, c and d ; they consist of a rod-shaped fulcrum, two rami, and two unci ; the outer points of the latter are connected by a very thin stirrup-shaped piece ; the manubria are absent. The tube is fixed at the point where the rami and unci meet and remains attached to the trophi when dissolved out with potash. The stomach, which begins at once behind the mastax, is very large, saccate, and interspersed with numerous large orange and white oil-globules ; it is partly coloured blue and partly green. The blue colour resides in the cells of the stomach, but the green appears to be due to food particles, and is sometimes absent. A small, conspicuously ciliated intestine is situated at the posterior end near the root of the foot ; it terminates in a cloaca in the usual way. Dr. Zacharias states that there is no anal opening, but this is incorrect, as I have observed the discharge of faeces. Gastric glands and lateral canals, if present, could not be distinguished owing to the nature of the stomach. A rounded ovary and a contractile vesicle, both situated near the foot, and four vibratile tags on each side are present. Animals have been observed to deposit their eggs on the glass slip, and they do not carry the eggs with them ; a prickly winter egg was seen in one animal. The brain is a large rounded and cellular sac with a neck reaching forward to the corona, and white in colour. A large red eye, often surrounded by white opaque granules, is situated on the under side of the brain mass. The dorsal antenna, consisting of a bundle of setae, protrudes out of a tubule situated above the brain and a little to the right of the median line ; lateral antennae of similar form are also present and asymmetrically placed ; the right lateral antenna protrudes low down on the side, near the posterior edge of the lorica, and the left is placed higher up nearer to the centre of the side, as shown in the figures. The antennae and their position are best seen when the animal slowly revolves on its longer axis, they then come into view one after the other. The male is not known. Size 1/250 to 1/150 in. Habitat: reservoir, Dundee (Hood, Caiman) ; large lake of Plon, Holstein (Zacharias). ( Ecistes brevis sp. n. Hood. PI. VII. fig. 4. Corona slightly oblong, body and foot stout and short, ventral antennae stout and of moderate length ; oral aperture prominent ; tube soft, gelatinous, roughly made. Eyes absent in adult, but present in the young. 449 Floscularia pelagica , &c. By G. F. Bousselet. This, the smallest of the known species of (Ecistes, was found by Mr. John Hood in 1889 in various lakes in Scotland ; it appears to be widely distributed but not very abundant. The corona is oval and quite as large in diameter as that of (Ecistes muscicola or socialis, but the dorsal gap appears to be absent. The tube is built singly on stems and leaves of Kanunculus and Myriophyllum and is like that of (E . crystallinus in appearance. The internal organs are normal, but the characters enumerated above distinguish it sufficiently from all other species of (Ecistes. Size 1/120 to 1/105 in. Habitat: lakes in Scotland and Ireland. Asplanchna priodonta Gosse. This, abundant and widely distributed species has been so often studied that it seems difficult to find anything new in its organization. Yet by the application of staining agents I have discovered that the body-cavity of [this rotifer is divided into two distinct compartments by a very thin membranous septum, running from the head to the posterior part of the body, in a plane at right angles with a dorso- ventral one, and in such a way that the body -cavity becomes divided into a larger ventral and smaller dorsal compartment. In the living animal, towards the dorsal side of the body, four threads are easily seen, running from side to side, across the body-cavity, markedly parallel to each other, like ruled lines. The septum appears stretched on these threads, but is so thin and so hyaline that it cannot be seen by ordinary means, and appears so far to have been overlooked. The dorsal compartment contains no organs except the nervous threads of the dorsal antennae, which pass through it, and two other, either nervous or muscular, threads, fastened to the integument a little below the antennae. The ventral compartment contains the stomach and all the other organs. The staining in toto of well-preserved rotifers by selective stains promises to produce very important results, and certainly will greatly facilitate the study of these animals, as ( by this means obscure and unsuspected details may often he made very prominent. 450 Transactions of the Society. X. — List of New Rotifers since 1889. By Charles F. Rousselet, F.R.M.S, ( Read June 21 st, 1893.) The Supplement to Messrs. Hudson and Gosse’s great -work on the Rotifera was published early in 1889, and, together with the two previous volumes, contains an account of all species that were known to the authors to the end of 1888. The publication of this book has had an immense stimulating effect upon students of this well-defined and interesting group of animals, with the result that no less than 186 new species have been described since that date. Almost all parts of the world have contributed to the number — from Greenland to Australia, and from China to America. Some of these so-called new species are, however, not new, and can be recognized as old friends, and some have been named twice over, while a number of others have been described and figured in so unsatisfactory a manner, that it will be quite impossible to recognize them again. It will be a difficult task to arrange all these species in the system and separate .the good species from those insufficiently known. A word of advice may not be out of place here to all workers in this field ; it is, Avoid as much as possible making new species. It must be borne in mind that a great many forms are imperfectly known, and have been described years ago, when the optical means at the disposal of observers were much inferior to those now available ; again, the animals have not always been observed under the most favourable conditions, and there can be no doubt that Rotifers, like most other animals, vary a little in different localities. It is therefore very natural that new details can sometimes now be seen which were over- looked or invisible before, and that other details are not exactly as originally described. Such corrections and variations should be recorded, but it is not necessary to make new species, especially in the more difficult and obscure genera, when animals are found which do not agree in every minute particular with the type. As a general rule a closely allied animal should only be described as new when the type itself is known to the observer. Descriptions of insufficiently observed animals should not be published ; it is better in such cases to make a note and await another opportunity. I am afraid Mr. Gosse has set a bad example in this respect, in naming a new species (Distemnia lahiatum) from a single observation, when the animal swam across the field of view and was then lost. But when a really new species has been found it should be figured and described in such a manner that the animal may readily be recog- nized when found again by a different observer, and a good figure is often worth more than a good description. A figure of the jaws should always be added. The true character of the jaws cannot List of New Rotifers since 1889. By G. F. Rousselet. 451 always, and even rarely, be made out in the living animal, but they are readily dissolved out with a drop of potash solution. Badly described and ill-figured species are worse than useless : they increase the difficulties and waste the time of observers, swell the literature, and are then dropped. I trust this list, with Bibliography attached, compiled with much care and labour from the widely scattered literature, and containing all new forms known to me to the end of June, will be useful to all workers on the Botifera, and that it will prevent the same species being described several times under different names. Ehrenberg’s j Euchlanis lynceus has been renamed three times within the last two years, and some of the animals associated with it in the three new genera are probably also identical. The numbers refer to the Bibliography at the end.* Rhizota. Floscularia torquilobata Thorpe (41). „ quadrilobata Hood (18). „ Gossei Hood (18). „ annulata Hood (17). „ diadema Petr. (36). „ Evansonii Anderson (2). „ spinata Hood (19). „ tenuilobata Anderson (1) (= F. Goronetta). „ pelagica Rousselet (40). „ unilobata Wierzejski (51). Limnias myriophylli Western (48). ( Ecistes Stephanion Anderson (1). ,, Wilsonii Anderson and Shephard (2). „ brevis Hood (40). Lacinularia natans Western (47). „ megalotrocha Thorpe (42). „ racemovata Thorpe (42). „ reticulata Anderson and Shephard (2). Cephalosiphon furcillatus Kellicott (27) ( = (Ecistes ptygura Ehr.). Megalotrocha procera Thorpe (42). „ spinosa Thorpe (42). Gonochilus unicornis Rousselet (39). Trocliosphsera solstitialis Thorpe (42). New Genera. Odotrocha speciosa Thorpe (42). Atrochus tentaculatus Wierzejski (52). * In view of the difficulty and delay in knowing of all the papers on Rotifera that are published in various parts of the world, and for the purpose of extending this list at a future date, I shall be greatly obliged if authors will be good enough to send me a copy of their memoirs addressed to the care of the Society. 452 Transactions of the Society. Bdelloida. Philodina hirsuta (Ehrenberg) Anderson (1, 26). „ commensalis Western (49). „ hexodonta Bergendal (12, 26). Rotifer mento Anderson (1, 26). „ ( Macrotrachela ) Roeperi Milne (32, 26). „ phaleratus Glascott (16). Actinurus ovatus Anderson (1, 26). Callidina magna Plate (34, 26). „ magna-calcarata Parsons (33, 26). „ ( Macrotrachela ) reclusa Milne (32, 26). „ „ multispinosa Thompson (43, 26). „ „ papillosa Thompson (43, 26). „ russeola Zelinka (55, 26). „ lutea Zelinka (55, 26). „ Muller i Zelinka (55, 26). „ Holzingeri Zelinka (55, 26). „ Lejeunise Zelinka (55, 26). „ plicata Bryce (8, 26). „ lata Bryce (8, 26). „ spinosa Bryce (8, 26). „ aspera Bryce (8, 26). „ cornigera Bryce (10). „ pusilla Bryce (10). „ sordida Western (49) (= G. longisrostris Janson). „ Isevis Bergendal (12, 26). „ tentaculata Bergendal (12, 26). ,, longirostris Janson (26). „ vorax Janson (26). Elirenbergii Janson (26). Adineta clauda Bryce (9). ,, barbata Janson (26). „ tuberculosa Janson (26). „ gracilis (Janson (26). Ploima. I. 11-loricata. Microcodon robustus Glascott (16). Asplanchna syringoides Plate (34). Ascomorpha ( Sacculus ) agilis Zacharias (54). „ ( „ ) amygdalum Zacharias (51). Synchseta monopus Plate (34). „ apus Plate (34). „ tavina Hood (20). „ grandis Zacharias (54). „ stylata Wierzejski (51). List of New Rotifers since 18S9. By C. F. Rousselet. 453 Triarthra longiseta var. limnetica Zacharias (54). Rhinops orbiculodiscus Thorpe (41). (Is not a Rhinops) Notops minor Rousselet (38). ,, pyqmeeus Caiman (14, 40, 54). „ lotos Thorpe (42). „ quadrangular is Glascott (16). „ forcipata Glascott (16). Taphrocampa Levinseni Bergendal (12). Pleurotrocha grandis Western (48, 49) (re-named Diglena ferox Western). aurita Bergendal (12). marina Bergendal (12). Notommata cuneata Thorpe (41). tarda Bergendal (12). gronlandica Bergendal (12). celer Bergendal (12). distinda Bergendal (12). longipes Bergendal (12). lucens Glascott (16). gigantea Glascott (16). volitans Glascott (16). cylindriformis Glascott (16). larviformis Glascott (16). rubra Glascott (16). Copeus Americanus Pell (35). Proales daphnicola Thompson (54). „ injlata Glascott (16). Furcularia tenuiseta Burn (4). neapolitana Daday (56). tubiformis King (28). semisetifera Glascott (16). megalocephala Glascott (16). rigida Glascott (16). Eosphora striata Glascott (16). Diglena ferox Western (49). „ elongata Glascott (16). „ rugosa Glascott (16), „ natans Bergendal (12). „ Hudsoni Glascott (16). „ dromius Glascott (16). „ injlata Glascott (16). „ revolvens Glascott (16). Distemma dubia Bergendal (12). Polyarthra platyptera var. euryptera (50, 51). latiremis Imhof (24). aptera Hood (19). (Same species). 454 Transactions of the Society. New Genera. Microcodides dubius Bergendal (12) (= Bhinops orbiculodiscus m Thorpe). Dinops longipes Western (47, 37) (= Asplanchnopus eupoda Gosse). Hudsonella picta Zacharias (54, 40) (= Notops pygmseus Caiman). Ilypopus Bitenbenki Bergendal (12). Notostemma macrocephala Bergendal (12). „ affinis Bergendal (12). „ bicarinata Bergendal (12). Diops marina Bergendal (12). Arthroglena Lutkeni Bergendal (12). Ploima. II. Loricata. Mastigocerca bicuspes Pell (35). „ cijlindrica Imhof (23). „ capucina Wierzejski and Zacharias (53, 51, 54). „ brachydactyla Glascott (16). Battulus antilopseus Petr. (36). „ bicornis Western (49). Coelopus similis Wierzejski (51). Dinocharis serica Thorpe (42). „ intermedia Bergendal (12). Stephanops intermedins Burn (3). „ dichtliaspis Anderson (1). „ gronlandicus Bergendal (12). Salpina cortina Thorpe (41). Euchlanis subversa Bryce (5) ( = Diplois propatula Grosse). „ parva Bousselet (39). „ elegans Wierzejski (51). Cathypna Stokesii Pell (35). Distyla clepressa Bryce (6). „ muscicola Bryce (6). „ Hudsonii Lord (29). „ Gossei Lord (29),. „ clara Bryce (7). „ agilis Bryce (7). „ inermis Bryce (7). „ ichthyoura Shephard (2). Monostyla arcuata Bryce (6). „ bifurca Bryce (7). „ galeata Bryce (7). „ Quennerstedti Bergendal (12). Colurus cristatus Bousselet (40). „ pachypodus Glascott (16). „ tessellatus Glascott (16). List of New Rotifers since 1889. By C. F. Bousselet. 455 Colurus rotundatus Daday (56). „ truncatus Daday (56). Metopedia rhomboidula Bryce (5). „ parvula Bryce (11). „ torquata Anderson (1). „ angulata Anderson (1) (= Notogonia EJirenbergii Perty). „ ovalis Shephard (2). „ a finis Bergen dal (12). Pterodina coeca Parsons (33). „ intermedia Anderson (1). „ trilobata Shephard (2). „ emarginata Wierzejski (51). Brachionus furculatus Thorpe (41). „ longipes Anderson (1). „ bidentata Anderson (1). „ forficula Wierzejski (50). „ dorcas var. spinosus Wierzejski (50). „ amphifureatus Imhof (21, 15) (= Schizocerca diversi- cornis Daday). „ tridens Hood (19). Schizocerca diversicornis var. homoceros Wierzejski (50). Anursea procurva Thorpe (41). „ scutata Thorpe (41). „ cruciformis Thompson (45). Notholca Hoodii Western (49). „ ambigua Bergendal (12). New Genera. Elosa Worrallii Lord (30). Anapus ovalis Bergendal (13). ( Gastroschiza lynceus Bergendal) (1 3) ( = Euchlanis lynceus Ehr.). „ triacantha Bergendal (13). „ foveolata Jagerskjold (25). „ flexilis Jagerskjold (25). ( Gastropus EJirenbergii Imhof) (22) ( = Euchlanis lynceus Ehr.). „ stylifer Imhof (22). „ Hudsonii Imhof (22). ( Bipalpus lynceus Wierzejski and Zacharias) (53) ( = Euchlanis lynceus Ehr.). „ vesiculosus Wierzejski and Zacharias (53, 51, 54). Scirtopoda. Pedalion fennicum Levander (31). 456 Transactions of the Society. Synonyms of rejected Genera not mentioned in the ‘ Rotifera,’ Hudson and Gosse. Theora uncinata Eyf. and Tessin (46) = Pleurotrocha uncinata Ehrbg. „ leptura Eyf. and Tessin (46) = Pleurotrocha leptura Ehrbg. Plagiognatha gracilis Tessin (46) Notommata lacinulata Ehrbg. Monommata longiseta Bartch and Bergendal (12, 46) = Furcu- laria longiseta Ehrbg. „ grandis Tessin (46) = Furcularia longiseta Ehrbg. Acanthodactylus tigris Tessin (46) = Coelopus porcellus Gosse. ,, rattulus Tessin (46) = Coelopus brachiurus Gosse. „ gracilis Tessin (46) = Coelopus tenuior Gosse „ rattus Tessin (46) = Mastigocerca rattus Ehrbg. „ carinatus Tessin (46) = Mastigocerca carinata Ehrbg. „ bicornis Tessin (46) = Mastigocerca bicornis Ehrbg. BIBLIOGRAPHY. N.B. — This Bibliography only refers to the New Rotifers in preceding list, and is not a complete bibliography of all the papers on Rotifera since 1889. 1. Anderson, H. H. — Notes on Indian Rotifers. Journ. Asiatic Society of Bengal, 1891, 3 pis. 2. Anderson, H. H., and J. Shephard — Notes on Victorian Rotifers. Proc. Royal Soc. of Victoria, IV. (1892) pp. 69-80, 2 pis. 3. Burn, Dr. W. Barnett — New and little-known Rotifers. Science Gossip, 1889, pp. 179-81, 2 figs. 4. New and little-known Rotifers. Science Gossip, 1890, pp. 34-36, 2 figs. 5. Bryce, David — Two new Species of Rotifers. Science Gossip, 1890, pp. 76-79, 5 figs. 6. Genus Distyla and three new Rotifers. Science Gossip, 1891, pp. 204-7, 8 figs. 7. Moss-dwelling Cathypnadae. Science Gossip, 1892, pp. 271-5, 5 figs. 8. On Macrotrachelous Callidinae. Journ. Quekett Micr. Club, V. (1892) pp. 15-23, 1 pi. 9. On the Adinetadse. Journ. Quekett Micr. Club, V. (1893) pp. 146-51, 1 pi. 10. Two new Species of Macrotrachelous Callidime. Journ. Quekett Micr. Club, V. (1893) pp. 196-201, 1 pi. 11. Metopedia parvula. Journ. Quekett Micr. Club, V. (1893) (to be published in October). List of New Rotifers since 1889. By C. F. Rousselet. 457 12. Bergendal, D. — Zur Rotatorienfauna Gronlands. Kongl. Fysiogra- fiska Salskapets Handlingar. Ny Foljd, 1891-2, III. Sep. ed. Lund, 1892, 6 pis. 13. Ehrenbergs Euchlanis lynceus wiedergefunden. Lunds Univ. Arsskrift, 1892 14. Calman, W. T. — On certain new or rare Kotifers from Forfarshire. Annals of Scott. Nat. Hist., Oct. 1892, 1 pi. 15. Daday, Dr. Eug. yon — Schizocerca diver sicornis Daday, oder Brachionus amphifurcatus, Imkof. Zool. Anz., 1891, p|3. 266-8. 16. Glascott, Miss L. S. — A List of some of the Rotifera of Ireland. Proc. Royal Dublin Society, VIII. (1893) pp. 29-86,5 pis. 17. Hood, John — Floscularia annulata. Science Gossip, 1888, pp. 8-10, 2 figs. 18. Floscularia quadrilobata and Floscularia Gossei. Inter. Journ. of Microscopy and Nat. Science, January and April, 1892, 4 pis. 19. Three new Rotifers. Journ. Quekett Micr. Club, V. (1893) (to be published in October) 1 pi. 20. Synchseta tavina. Inter. Journ. of Microscopy and Nat. Science, 1893 (to be published in October) 1 pi. 21. Imhof, Dr. 0. E. — Notizen iib. die pelag. Fauna der Siisswasser- becken. Zool. Anz., 1887, pp. 457-60. 22. Fauna der Siisswasserbecken. Zool. Anz., 1888, pp. 166-72. 23. Ueber die pelag. Fauna einiger Seen d. Schwarzwaldes. Zool. Anz., 1891, pp. 33-8. 24. Brachionus amphifurcatus and Polyarthra latiremis. Zool. Anz., 1891, pp. 125, 446-7. 25. Jagerskiold, L. A. — Zwei der Fuchlanis lynceus verwandte neuo Rotatorien. Zool. Anz., 1892, pp. 447-9, 2 figs. 26. Janson, Dr. Otto — Die Rotatorien-familie der Philodinceen. Abhandl. des Natw. Ver. Bremen, XII. (1893) ; also sep. ed. Marburg, 1893, 5 pis. 27. Kellicott, Dr. D. S. — Cephalosiphon furcillatus. Proc. of Amer. Soc. of Micr., XI. (1889) p. 32, 1 fig. 28. King, Hy. W. — Pond Life from the West Indies. Journ. Quekett Micr. Club, V. (1893) pp. 137-45, 2 pis. 29. Lord, J. E. — The Genus Bistyla. Science Gossip, 1890, pp. 201-2, 5 figs. 30. A new Rotifer, Elosa Worrallii. Inter. Journ. of Micr. and Nat. Science, 1891, 1 pi. 31. Lkvander, K. M. — Eine neue Pedalion-Art. Zool. Anz., 1892, pp. 402-4, and 1893, pp. 26-7. 32. Milne, E. — Rotifer as a Parasite or Tube-dweller. Proc. Phil. Soc. Glasgow, 1888-9, XX. pp. 48-50, 2 figs. 33. Parsons, F. A. — Note on two Rotifers found at Epping Forest. Journ. Quekett Micr. Club, IV. (1892) pp. 378-80, 1 pi. 458 Transactions of the Society. 34. Plate, Dr. L. — Rotatorienfauna des bottnischen Meerbusens. Zeitscbr. f. Wiss. Zool., XLIX. (1889) pp. 1-42. 35. Pell, Alfred — Three new Rotifers. The Microscope, X. (1890) pp. 143-5, 3 figs. 36. Petr, F. — Bohmische Rotatorien. SitzB. K. Bohm. Ges. Wiss., 1890, pp. 215-05, 2 figs. 37. Rousselet, C. F. — Note on Dinops longipes. Journ. Quekett Micr. Club, IV. (1890) p. 263. 38. On Notops minor. A new Rotifer. Journ. Quekett Micr. Club, IV. (1892) pp. 359-60, 1 pi. 39. On Conochilus unicornis and Euchlanis parva. Journ. Quekett Micr. Club, IV. (1892) pp. 367-70, 1 pi. 40. On Floscularia pelagica, &c. Journ. Royal Micr. Soc., 1893, pp. 444-9, 1 pi. 41. Thorpe, Surgeon V. Gunson— New and Foreign Rotifera. Journ. Royal Micr. Soc., 1891, pp. 301-6, 2 pis. 42. The Rotifera of China. Journ. Royal Micr. Soc., 1893, pp. 145-52, 2 pis. 43. Thompson, Percy G. — Moss-haunting Rotifers. Science Gossip, 1892, pp. 56-9, 8 figs. 44. Parasitic Tendency of Rotifers. Science Gossip, 1892, pp. 219-21, 1 fig. 45. Thompson, I. C. — Anursea cruciformis. Trans. Liverpool Biol. Soc., 1892, pp. 77-81. 46. Tessin-Butzow, Dr. G. — Rotatorien der Umgegend von Rostock. Archiv 43 d. Freunde d. Naturg. i. Mecklbg., pp. 133-74, 2 pis. 1886? 47. Western, Geo. — Notes on Rotifers. Journ. Quekett Micr. Club, IV. (1891) pp. 254-8, 1 pi. 48. Notes on Rotifers. Journ. Quekett Micr. Club, IV. (1891) pp. 320-322, 1 pi. 49. Notes on Rotifers. Journ. Quekett Micr. Club, V. (1893) pp. 155-60, 1 pi. 50. Wierzejski, Prof. Dr. A. — Liste des Rotiferes observes en Galicie. Bull. Soc. Zool. de France, XVI. (1891) p. 49. 51. Rotatoria (Wrotki) Galicyi. Akademie d. Wiss. in Krakau, 1892, pp. 160-265, 3 pis. (also reprint Krakau, 1893, Polish). 52. Atrochus tentaculatus. Ein Raderthier ohne Raderorgan. Zeitschr. f. Wiss. Zool., LV. (1893) pp. 696-712, 1 pi. 53. und Dr. O. Zacharias — Neue Rotatorien des Siisswassers. Zeitschr. f. Wiss. Zool., LVI. (1893) pp. 236-43, 1 pi. 54. Zacharias, Dr. O. — Forschungsberichte aus der Biol. Station zu Plon. 1893, I. Theil, 1 pi. 55. Zelinka, Dr. Carl — Studien fiber Raderthiere, III. Zeitschr. f. Wiss. Zool., LIJI. (1891) pp. 323-428, 6 pis. 56. Daday, Dr. Eug. Von — Rotatorien des Golfes von Neapel. Math. Termes. Ertes. (Math. Nat. Anz. d. Akad.) VIII. pp. 4-8. Math. Nat. Ber. aus Ungarn, VIII. (1891) pp. 349-53. 459 SUMMARY OP CURRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY {'principally Invertebrata and Crypto gamia), MICROSCOPY, Ac., INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS. ZOOLOGY. A. VERTEBRATA: — Embryology, Histology, and General. a. Embryology. f Parthenogenetic Segmentation of Ova of Mammals .{ — M. L. F. Henneguy’s observations on the degeneration of the ova of Mammals confirm and extend those of Flemming and Schottlander. They show that the ovule in follicles that are undergoing atresia may present not only a precocious maturity, as evidenced by the appearance of a directive spindle and a polar globule, but also a commencing, irregular, partheno- genetic segmentation. They further show that the chromatic substance of the nucleus, when dispersed in the cytoplasm, continues to exercise an action on it. In the absence of centrosomes the chromosomes become centres of attraction and orientation for the achromatic filaments. Origin of Mesoderm.§ — Dr. J. Perenyi gives the following account of the origin of the mesoderm in the frog. In the blastula the dark pole consists of three layers of cells. These curve inwards at the equatorial margin at one side, and a unilateral epibole results. This epibole begins in the form of an angle with a right and a left margin, i. e. the duplica- tion takes place in two portions. Subsequently, in the position defined by the two margins, there arises the primitive streak, the basis of the medul- lary groove. The original orientation of the egg changes ; the dorsal part of the embryo appears at one side of the white pole, the ventral part on the dark pole. The originally outermost layer of ingrowing cells extends first vertically and forms the notochord, then horizontally, to right 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. t This section includes not only papers relating to Embryology properly so called, but also those dealing with Evolution, Development, and Reproduction, and allied subjects. J Comptes Rendus, cxvi. (1893) pp. 1157-9. § Math. Nat. Ber. Ungarn, viii. (1891) pp. 272-8 (2 pis.); Math. Termes. Ertes. (Math. Nat. Anzeig. Akad.), viii. pp. 11-9. 1893. 2 K 460 SUMMARY OF CURRENT RESEARCHES RELATING TO left, and forms the endoderm. But the two rows of cells beneath the original covering cells curve to right and left, and form the mesoderm. The notochord is constricted off, first from the covering cells, then from the endoderm. Where the duplication of rows of cells begins, is not the blastopore, but the beginning of the notochord. The blastopore lies where the duplication of cell-rows ends, i.e. at the end of the notochord. Keeping pace with the development of the germinal layers, the notochord comes to lie along the embryo between the two mesoderm plates. Origin and History of the Graafian Follicle.* — Dr. J. Schottlaender has investigated the ovaries of the cat, rabbit, pig, &c., and has com- pared them with the human ovary. In the human ovary, ova and follicular epithelium arise directly from the germinal epithelium. Waldeyer’s Eiballen are first formed. From these, with increased growth of connective tissue, there arise (a) the Pfliiger-Valentin tubules, ( b ) the typical primordial follicles, (c) atypical primordial follicles, with two or three ova (which secondarily become primordial), ( d ) Eibal- lenfollikel , which arise by connective delimitation of larger or smaller portions of the Eiballen and modification of these into follicles, and (e) tubular follicles which arise by connective delimitation of larger or smaller parts of (a). It seems likely that most, if not all, of the larger follicles in the ovary of a child are Eiballen- or tubule-follicles ; these are rapidly formed, and that they may represent an organic economy the author explains. He gives a decided negative answer to the question whether new Graafian follicles arise in the adult human ovary. The unchanged Graafian follicle is described in detail, as regards ovum, follicular epithelium, and theca folliculi. The degeneration of an unburst follicle (follicular atresia) is a physiological process, whose chief criterion is to be found in the state of the follicular ovum. The state of the follicular epithelium is less important, for the epithelium always degenerates in the formation of the liquor. In the ovum and in epithelial cells, the nucleus undergoes (a) chromatolysis or (6) atrophy, the cell-substance exhibits degeneration either fatty (a) or otherwise (/ 3 ) (perhaps albuminous ?). There are various combinations of (a) and (b) with (a) and (/ 3 ). The effect of (a) and (j8) is to liquefy the cell-substance which seems to lead to hyaline coagulation of the ovum. Even the primitive ova may exhibit degenera- tion. The corpus luteum arises without the participation of epithelial or wandering cells by the proliferation of the epithelioid cells of the theca interna of a follicle which is ready to burst. Placenta of Rodents.f — Dr. A. Fleischmann has succeeded in demonstrating the uniformity of placentation in the Rodentia. He has previously shown that the so-called “ inversion ” in mouse and guinea- pig can be harmonized with what occurs in rabbit and porcupine. He has now succeeded in harmonizing the varied relations of the blasto- dermic vesicle to the lumen of the uterus. A study of Spermophilus citillus has enabled him to connect the state of affairs in Lepus and Sciurus with that in Mus, Cricetus , Arvicola , and Cavia. In all cases, what may be called the prodiscoidal type is demonstrable. The techni- * Arch. f. Mikr. Anat., xli. (1893) pp. 219-94 (2 pis.). f SB. K. Preuss. Akad. d. Wiss., 1892, pp. 445-57 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 461 calities make a summary of an already condensed narrative exceedingly difficult; we therefore restrict our report to noticing the important result gained — that there is a morphological unity in the placentation of Rodentia. A Duck with Drake’s Plumage.* — Mr. A. Willey has examined a female of Anas boschas var. dom. L., whose plumage closely resembled that of a male. The oviduct was normal in length and form, except that the wall of the lower part was thickened and the lumen divided into two. There was no mesovarium. The ovary was much reduced ; no follicular epithelium was recognizable ; all the ova were invaded by wandering cells, and were being absorbed. For two years the bird had been kept in the Zoological Institute at Freiburg, and had laid no eggs ; but its original owner stated that it had laid for several years, and that it had exhibited male plumage from its youth. Is this then a case of a female organism inheriting some of the secondary sexual characters of the male ; or was the male plumage correlated with a degeneration of the essential female organs ? Mr. Willey points out that a sure answer cannot be given without knowing more definitely about the bird’s life- history. Development of the Teleostean Vertebral Column. | — Dr. C.Scheel has studied this in embryos of Bhodeus amarus, trout, salmon, &c., and comes to the following conclusions : — In Teleostei there is a regular, single-layered, chorda-epithelium. The notochord is surrounded by a non-cellular sheath, and outside this by a non-cellular elastic membrane. In Bhodeus the superior arch and the parapophysis of each side have a common origin in an aggregation of cartilage cells lateral to the notochord. In the trout there is apparent discontinuity between superior arch and parapophysis, but the inter- vening perichondrium unites them. In Bhodeus the superior arches unite in a median process, as is the case also posteriorly in trouts. Medianly and anteriorly, however, the arches in the trout run parallel, and small transverse pieces form a (primitive) bridge between them. Cartilaginous fin-rays extend along the whole dorsal surface far beyond the definite fin-regions — a fact which proves the primitive dorsal extension of the fin. In Bhodeus there is, especially in the anterior region, a very great development of cartilage around the notochord — forming a thick ring — the common basis of superior arches and parapophyses. In trouts this mass is much reduced. The inferior caudal arches are ventrally directed parapophyses, but not true haemapophyses. Indeed, these are not developed in Teleosteans, except perhaps in the anterior trunk of Bhodeus. The ribs are abjointed from the parapophyses, and those of Teleosteans must be regarded as homologous with those of Amphibians. Development of the Pancreas.J— Dr. E. Goeppert has studied this in embryos of the salmon-trout. The organ makes its first distinct appearance in embryos twenty-one days old. A dorsal rudiment — a direct outgrowth of the gut — is first seen, but by the thirtieth day there are two other outgrowths on the ventral surface. These arise from the * Ber. Nat. Gesell. Freiburg i. B., vi. (1891) pp. 57-61 (1 pi. and 2 figs.). t Morphol. Jahrb., xx. (1893) pp. 1-47 (3 pis.). j Tom. cit , pp. 90-111 (6 figs.). 2 k 2 462 SUMMARY OF CURRENT RESEARCHES RELATING TO primitive duct of the liver. Subsequently there is a union of the three parts. The duct of the dorsal portion degenerates ; the ducts of the two ventral parts unite in a common terminal region (ductus Wirsungia- nus), which opens first into the ductus choledochus, but ultimately into the gut. In the sturgeon there are four rudiments of the pancreas, as v. Kupf- fer has shown ; in Amphibians there are three ; in the chick (according to Felix) there are three ; in at least some mammals there is a dorsal and a ventral rudiment. It is probable that the fourfold origin, as seen in the sturgeon, is the primitive condition, and that the most posterior portion has in most cases been dispensed with. £. Histology. Attractive Sphere.* — Dr. 0. Van der Stricht, after a short historical introduction, gives an account of his observations on the attractive sphere in the eggs of Triton , and in cartilage cells. In the former some differences were observed from the phenomena described for the Trout and for Siredon ; in the eggs of Triton the division of the attractive sphere is, ordinarily, effected during the quiescent stage of the nucleus, rarely in the anaphase of the mother-nucleus, and exceptionally in the metaphase. The author’s account of what he observed in cartilage-cells cannot unfortunately be lucidly reproduced without copies of the figures to which he frequently refers. Nuclear Division in Cut Nerve-fibre s.f — Dr. G. Bizzozero points out, in correction of a paper by 0. von Biingner, that the late Dr. A. A. Torre discovered in 1884 the mitotic multiplication of the nuclei of Schwann’s sheath. This multiplication is exhibited along the whole course of the peripheral stump of a cut nerve, and the resulting cells are able to absorb the myelin drops which result from the degeneration of the fibres. Dr. Torre also showed that in normal medullated nerve- fibres the multiplication of nuclei in Schwann’s sheath is mitotic. Neuroglia-cells in Peripheral Nerves.J — Dr. E. Kallius finds numerous neuroglia cells uniformly distributed throughout the optic nerve. Their processes form a very fine-meshed network in the inter- stices of which the fibres lie. They were demonstrated in man, horse, ox, dog, rabbit, and mouse. Their occurrence corroborates the embryo- logical conclusion that the optic nerve is a modified portion of the brain. They were also found in the Trigeminal, Auditory, and Vagus, but were abundant only at the roots of these nerves. Cell-multiplication and Replacements — Prof. J. Frenzel has an essay on this subject, the gist of which seems to be expressed in the following sentence : — Under the term cell-division we include two essentially different phenomena : On the one hand there is cell-multipli- cation which by mitosis results in the growth of an organ or of part of an organ, and there is cell-replacement which proceeds by amitotic division with the result of replacing lost cells. That this contrast, * Arch, de Biol., xii. (1892) pp. 741-63 (1 pi.). t Arch. f. Mikr, Anat., xli. (1893) p. 338. J Nachr. K. Gesell. Wiss. Gotting., 1892, pp. 513-5. § Biol. Centralbl., xiii. (1893) pp. 238-43. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 463 demonstrable for Invertebrates, is likely to be to some extent demon- strable for Vertebrates as well, is one of the author’s contentions. y. General. Phosphorus in the Tissues.* — Drs. L. Lilienfeld and A. Monti have made a series of microchemical investigations bearing upon the localiza- tion of phosphorus in the tissues both of plants and of animals. Their general result is that young cells capable of reproduction are always rich in phosphorus, while much differentiated cells, in which the power of reproduction tends to be lost, have nuclei poor in phosphorus. B. INVERTEBRATA. Mollusca. y. Gastropoda. Olfactory Organs of Helix.f — Dr. A. B. Griffiths contends that Sochaczewer’s experiments, by which he showed that the tentacula of Helix poraatia are not olfactory organs, were untrustworthy from his use of turpentine, which gives off a vapour that is irritating to the sensitive tissues generally. If snails are placed on flat slabs, the edges of which are smeared with eau de Cologne, methyl, ether, or ethyl acetate, liquids the vapours of which are not irritants, such as have the tentacula removed gradually approach the edges of the slabs, while those whose tentacles are uninjured turn away from the edges. He concludes, therefore, that the tentacula are the seat of the olfactory organs in Helix. Opisthobranchs of the ‘ Hirondelle.’ t— Dr. R. Bergh describes the Opisthobranchs collected by the Prince of Monaco on the ‘ Hirondelle.’ The work is chiefly descriptive of the structure of a few species, some of which are new. Pleurobranchillus is a new genus, resembling Pleuro- brancJms in some points. Histology of Muscle in Heteropods and Pteropods.§ — Herr J. Wackwitz has investigated species of Carinaria, Pterotrachea, Atlanta , Hyalea, Cleodora, Creseis, &c., and has compared their muscle with that of other molluscs. Within the relatively narrow range of the two groups above mentioned, there is great histological diversity as regards muscle. There are smooth fibres and striped fibres and grada- tions between them ; and both kinds of fibres occur in two forms, either poor in contractile substance and rich in medullary substance, or the reverse. In those molluscs which creep — a mode of locomotion more laborious than swimming — the contractile substance predominates. And since the medullary substance, through which compensation for waste is obtained, is relatively less, the muscle is adapted for powerful but slow activity. In Heteropods and Pteropods the reverse holds good. In regard to the occurrence of smooth and striped muscle, the author corroborates the conclusion that striped muscle is adapted for more energetic and rapid activity than smooth muscle. * Atti R. Accad. Lincei — Rend., cclxxxix. (1892) pp. 354-8. f Proc. Roy. Soc. Edin., xix. (1892) pp. 198 and 9. X ‘ Resultats Scientifiques,’ &c., iv. (1893) 35 pp., 4 pis. § Zool. Beitr., iii. (1892) pp. 129-60 (3 pis.). 464 SUMMARY OF CURRENT RESEARCHES RELATING TO Range of Placost.ylus.* — Mr. E. Hedley makes the geographical range of this snail a text for a study in ancient geography. He thinks that the area which it occupies should rank as a zoological province to be called Melanesia ; it would embrace the archipelagoes of Solomon, Fiji, New Hebrides, Loyalty, New Caledonia, Norfolk I. (?), Lord Howe I., and New Zealand. This area was never connected with nor populated from Australia, and its fauna was probably derived from Papua via New Britain. The presence of genera common to Australia and New Zealand is explicable by the supposition that they derive, in either case, from New Guinea as a common source. 5. Lamellibranchiata. Ocular Nerves of Spondylus gcederopus.j — M. J. Chatin reminds the student that he has already demonstrated the existence, in the eyes of Pectens, of an optic nerve which supplies the retina, and of ophthalmic nerves which innervate the peripheral parts. These two kinds of nerves are found in Spondylus goederopus , where they arise separately from the circumpallial nerve. With osmic acid the optic nerve is stained black, while the ophthalmic nerves are hardly tinted at all. The staining is due to the presence of myelin, a very rare occurrence among Inverte- brates. Food of Oysters, Clams, and Mussels.! — Mr. J. P. Lotsy, on sucking out by a pipette the contents of the stomach, found an abundance of diatoms, but a total absence of Copepods, although these were very abundant in the surrounding water. Cultures of diatoms were taken by the animals, but hashes of Copepods were either refused at once, or, if accepted, were instantly rejected and that forcibly, being driven to a distance of six or seven inches. Pedal Impression of Pachyerisma.§ — Prof. G. Boehm points out that Pachyerisma bears a distinct impression of a pedal muscle on the under surface of the anterior lateral tooth, therefore P achy meg alodon cannot be separated from Pachyerisma , as Neumayr thought necessary. Lithiotis problematica Giimbel.||— Prof. G. Boehm finds that the fossils so named are oysters. Often only the ligament region remains. The frequent grooves in this region are due to weathering, and are also seen in Tertiary oysters. He finds further that Trichites Loppianus Tausch is an Ostrea , and near the so-called Lithiotis. The very numerous white bands and streaks in the grey limestone are not wholly sections of the above-mentioned oysters, but also due to Perna. Molluscoida. a. Tunicata. Origin of Metagenesis in Tunicata.lf — Prof. W. Salensky sums up the results of an interesting essay on this subject in the following terms : — * Proc. Linn. Soc. N.S.W., vii. (1893) pp. 335-9. f Comptes Rendus, cxvi. (1893) pp. 1156 and 7. X John Hopkins Univ. Circ., xii. (1893) pp. 104 and 5. § Ber. Nat. Gesell. Freiburg i. B., vi. (1892) pp. 119-20. || Tom. cit., pp. 65-80 (3 pis.). Biol. Centralbl., xiii. (1893) pp. 126-46. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 465 (1) The primitive form of metagenesis of the Tunicata is to be found in those species of Synascidians which are capable of multiplying asexually in the larval stage. (2) Distaplia alone of the Synascidians exhibits an alternation of generation, while the development of the Didemniidae has no relation to that process. (3) The primordial bud of the Distaplia-laYva, is to be regarded as an intermediate stage between the simple bud and the stolo prolifer of the metagene tic Tunicata. (4) The stolo prolifer is derived from the bud which began to divide before separation from the mother-body. (5) In the oldest metagenetic forms the cc nurse ” died after the production of the sexual generation; in the course of metagenesis the length of the “ nurse’s ” life increased. In this connection Doliolum represents an intermediate stage between the Synascidiac and the Salpidae. Deglutition in Synascidiae.* — M. S. Jourdain, from observations on living specimens of Clavelina and PeropJiora , comes to the conclusion that one of the functions of the vibratile pit is the secretion of mucus ; by the aid of this the food particles are agglutinated into a cord, which is conveyed by the ciliated branchial band into the stomach. Nervous System in Embryos of Distaplia.j — Prof. W. Salensky has investigated the nature and development of the nervous system in embryos and larvae of Distaplia magnilarva. The larval nervous system consists of a somewhat complex cerebral vesicle, a trunk portion, and a tail portion. The cerebral vesicle is a vesicular tube, opening an- teriorly into the oral cavity, continued posteriorly into the trunk region, and expanded medianly into a sensory vesicle. This sensory vesicle lies between what may be called the Trichterblase and the Ganglionblase. In young embryos the anterior end of the funnel-vesicle is blind ; it is at first in a line with the rest of the brain, but is subsequently shunted to the left side. In connection with the sensory vesicle, the author describes the eye and the auditory organ. All the parts of the sensory vesicle, viz. retina, lens, pigment layer, and otolith cell, arise from the differentiation of one and the same epithelial layer of the primitive cerebral vesicle. The ganglion-vesicle lies between the choroid fold and the trunk region. Its lower wall is anatomically and genetically connected with the posterior part of the cerebral ganglion ; indeed the latter arises from a thickening of the inferior wall of the ganglion vesicle. The trunk region ( Bumpfmarlc ) connects the brain and the cord, and consists of an epithelial canal (part of the original neural canal) and of a well-developed layer of nerve-cells ( Bumpf-ganglion ) which has its origin from the cells of the posterior wall of the sensory vesicle. This Bumpf-ganglion is perhaps to be regarded as a great reflex centre for the larva, which through the cerebral ganglion conveys the results of sensory stimuli to the muscles. The degeneration of the cord during embryonic life is briefly referred to. After comparing in detail the nervous system of this larval Ascidian with that of other * Bull. Soc. Philomath., iv. (1892) pp. 35 and 6. See Ann. and Mag. Nat. Hist., x. (1892) pp. 482 and 3. f Morphol. Jahrb., xs. (1893) pp. 48-74 (2 pis.). 466 SUMMARY OF CURRENT RESEARCHES RELATING TO Chordata, Salensky comes to the important conclusions that the sensory vesicle is homologous with the epiphysis and the Ascidian eye with the parietal eye. Origin of Organs of Salpa.* — Prof. W. K. Brooks has published an abstract of one of the chapters of his forthcoming memoir on the genus Salpa. He remarks that “ stated in a word the most remarkable peculi- arity of the $aZpa-embryo is this: it is blocked out in follicle cells which form layers and undergo other changes, which result in an outline or model of all the general features in the organization of the embryo. While this process is going on the development of the blastomeres is retarded, so that they are carried into their final positions in the embryo while still in a very rudimentary condition. Finally, when they have reached the places which they are to occupy, they undergo rapid multi- plication and growth, and build up the tissues of the body directly, while the scaffolding of follicle cells is torn down and used up as food for the true embryonic cells.” With regard to the aggregated Salpse , which during development undergo complicated changes of position, Salensky and Seeliger are said to have totally failed to understand the changes. The author now amplifies and expands the statement made by him some years ago, that the Salpa- chain is, morphologically, a single row of Salpse , all in the same position, with their dorsal surfaces proximal and their right sides on the right of the stolon. With regard to the ectoderm of the embryo, Salensky would again appear to have misunderstood the facts ; Prof. Brooks finds that it is derived from the extra-follicular blastomeres, and that the epithelial capsule is a transitory structure which is lost as the ectoderm re- places it. The caudal nervous system is represented by scattered blastomeres, which soon degenerate and disappear. The ganglion is formed as an invaginated fold of the somatic layer of the follicle, and the ganglionic blastomeres pass with it from the ectodermal ridge, and become com- pletely folded in among the follicle cells. The nerve- tube of the stolon is formed from the ectoderm in the middle line of the upper surface of the stolon. In the aggregated Salpse the nerve-tube arises as a solid rod, but it soon acquires a lumen ; as the ectodermal folds grow inwards and mark out the bodies of the Salpse , they cut the tube up into a series of ganglionic vesicles, one for each Salpa. The apparent migration of the ganglion is the result of secondary changes in the position of the bodies of the Salpse , and is not due to any change in the relation of the ganglion to other organs of the body. The history of the perithoracic tubes and of the atrium cannot be described intelligibly without figures ; the author finds that they are formed before the cavity of the pharynx is hollowed out in the mass of visceral follicle cells, and he shows that Salensky mistook them for the primitive digestive cavity.” In the aggregated forms the rudiment of each contains two perithoracic vesicles, derived from the right and left perithoracic tubes of the stolon ; their vesicles give rise to the peritho- racic system, and to nothing else. Throughout its whole history this * John Hopkins Univ. Circ., xii. (1893) pp. 93-7. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 467 system is bilaterally symmetrical, although the symmetry is hidden by the changes which take place in the position of the plane of symmetry during growth. The author cannot accept the account given by Seeliger, who met with difficulties in Salpa democratica that are not to be found in S. pinnala, where the stolon is straight. The cavity of the pharynx arises by the degeneration of the visceral follicle cells ; its endodermal epithelium is derived from the blastomeres, and the gut is formed as a diverticulum of the pharynx. In the concluding paragraphs the author describes the endodermal tube of the stolon, and the digestive tract of the aggregated Saljpa ; here again he compares his results with the results of Seeliger and Salensky. Nutrition of Embryo of Salpa.* — Prof. W. K. Brooks points out that the generally accepted idea that the nourishment and aeration of the embryo of Salpa is on the same lines as that of the Mammalian foetus is quite incorrect. As the Salpa-e mbryo is bathed by the water which is constantly flowing past it, there does not seem to be either any need for or adaptation of structure for a respiratory placenta. Nourish- ment, moreover, is effected in a way quite unlike anything which has been described in the Mammalia. The remarkable and rapid growth of the young Salpa is only partly due to cell-multiplication, for there is a growth of the individual cells, which, instead of growing smaller with repeated divisions, actually increase in size in all parts of the body. The placenta of Salpa is an organ for the nourishment of the cells of the placenta by the blood of the chain -Salpa ; and the subsequent degeneration of these cells, after they have migrated into the body of the embryo, supplies the material for the growth of the embryo. It would seem that those investigators who have described the placenta as divided into a foetal chamber and a maternal one have been misled by an erroneous notion as to its function. The placenta is not the only nutritive organ, as the follicle also supplies material which is available for the rapid construction of the body of the embryo. The cells of this follicle become detached and degenerate, and though it is not possible to trace the history of every cell from first to last there is sufficient evidence that the function of the follicle of Salpa is exclusively nutritive; the organ is transitory and embryonic. New Species of Octacnemus.j — Mr. M. M. Metcalf describes a deep-sea Tunicate from Patagonia, which shows many resemblances to 0. bithyus of Moseley, but differs from it in being colonial and not solitary. It may, of course, be the chain-form and Moseley’s the solitary form of one and the same species. Meantime it is called 0. patagoni- ensis. £. Bryozoa. Classification of Cheilostoma.j: — In an essay on British Palaeogene Bryozoa, Mr. J. W. Gregory proposes the following classification of the order Cheilostoma: — * t John Hopkins Uuiv. Circ., xii. (1893) pp. 97 and 8. Tom. cit., pp. 98-100 (6 figs.). 468 SUMMARY OF CURRENT RESEARCHES RELATING TO I. Suborder. Stolonata. Forms with simple tubular zooecia, and terminal or subterminal apertures. Families : iEteidae, Eucra- tiidae, and Chlidoniidae. II. Suborder. Cellulariina. A group of forms with simple zooecia and tufted pliytoid zoaria, and probably including representa- tives of the three following suborders. Families : Cellu- lariidae, Bicellariidae, Epistomiidae, Catenicellidae, and Bifaxa- riidae. III. Suborder. Athyriata. Cheilostoma with the front wall uncal- cified or incompletely calcified. Families : Farciminariidae, Flustridae, Membraniporidae, Cribilinidae, Microporidae, Stega- noporellidae, and Cellariidae. IY. Suborder. Schizothyriata. Cheilostoma which are schizosto- matous or trypiate. Families : Schizoporellidae, Adeonellidae, and Microporellidae. Y. Suborder. Holothyriata. Holostomatous Cheilostoma which have the front wall wholly calcified. Families: Lepralliidae, Celleporidae, and Smittiidae. y. Brachiopoda. Structure of Brachiopoda.* — Prof. F. Blochmann devotes the first part of his work to the anatomy of Crania , of which he gives a detailed descriptive account of the kind which it is not possible to abstract. The student will, however, doubtless find the text, with the illustrations, an important aid in the study of this difficult group. Arthropoda. a. Insecta. Larvae of British Butterflies and Moths.f — The fifth volume of this work of the late William Buckler was only in part edited by Mr. H. T. Stainton, who, unfortunately, died before it left his hands. His task was completed by Mr. W. D. Roebuck, under the supervision of Mr. G. T. Porritt. In the present volume the Noctuee, which will be completed in the next, are continued ; it is only necessary to call the attention of the entomologist to the appearance of another part of this work. Classification of Hesperiidse.* — Mr. E. Y. Watson proposes a classi- fication of the Hesperiidae, and revises the genera. The characters which have been found of the greatest value in dividing the family into groups are, firstly, the position of vein 5 of the fore-wing, taken in conjunction with the length of the cell ; the position assumed by the species when in a state of complete repose is a character of great importance, and a third useful point is to be found in the secondary male characters found on the upper side of the fore- wing. As subfamilies he recognizes (1) the New World Pyrrhopyginae, (2) the Hesperiinae, in which the antennae nearly always end in a fine point, and (3) the Pamphilinae. The author fully diagnoses the genera, many of which are new. * ‘ Untersuchungen liber den Bau der Brackiopoden,’ 4to, Jena, 3892, 66 pp., Atlas of 7 pis. f London. For the Ray Society. 1893, 8vo, 90 pp., pis. lxx. to lxxxvi. I Proc. Zool. Soc., 1893, pp. 3-132 (3 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 469 Mimetic Forms of Hypolimnas.* * * § — Col. C. Swinhoc’s investigations, an abstract of which has been published, had for their subject the changes undergone by the species of a small group of Butterflies as they are traced from one locality to another, and to ascertain the bearing of the facts on the theory of mimicry. Representations of the Indian Hypolimnas bolina are found in Malaya, Polynesia, and Africa ; though the local represen- tatives differ from one another and from the Indian form, they agree in possessing in one or both sexes a more or less superficial resemblance to some conspicuous species belonging to a specially defended group inha- biting the same locality. The author would appear to have devoted himself to such questions as (1) the special liability of the female to become mimetic; (2) the ancestral form from which the various mimetic varieties have been de- rived; (3) the^ mimetic resemblance to different species in the same locality ; (4) the divergent conditions under which mimicry appears in closely related species: and (5) the relation between selection and variation in the production of mimetic resemblance. Ants’ Nests. t — Dr. A. Forel gives a most interesting account of the nests of ants, nests temporary and permanent, nests natural and artificial, nests of earth and of wood and of other materials, nests tenanted by one kind of ant or by several, and so on. It is a fortunate thing when a master of the subject gives us in so pleasant a manner the results of his long experience. Notes on Ants.f — M. A. Forel has some notes on Acanthognathus ocellatus Mayr. Three long stylets end in a recurved trident, and each bears near its base a long strong tooth, curved downwards and inwards and ending in two denticles. The specimen was sent to Forel by Dr. Muller of Blumenau (S. Brazil) who gives a short description of the habits of this ant. With the bidentate end of the lower teeth the ants seize and carry their eggs and particles of earth. In the allied Strumigenys there are no lower teeth. F. W. Urich from Trinidad observes that Camponotus alriceps is nocturnal ; Cryptocerus atratus raises its abdomen in a threatening manner on to its head but does not sting ; Odontomachus hsematodes and Anochetus ( Stenomyrmex ) emar- ginatus , which sting virulently, are called “ Tack-Tack ” by the natives on account of the noise which they make by sharply shutting their man- dibles ; Azteca instabilis and Dolichoderus bispinosus have an aromatic odour ; the nests of the last-named are formed from the vegetable debris and particles of earth glued together by a resinous secretion, and not merely from the capsules of Bombax ceiba as has been believed. The Pharaoh- Ant.§ — Dr. J. Ritzema Bos gives an interesting report on Monomorium Pharaonis — a happily rare import to North Europe. The ants invaded the postal buildings, &c., in Leeuwarden (Friesland). They are so small that they cannot do much harm in the way of destroy- ing the eatables over which they swarm, for a million do not weigh * Proc. Rov. Soc. Lond., liii. (1893) p. 47. t Neujahrsblatt Nat. Ges. Zurich, xcv. (1892) p. 37 (1 pi.), t Bull. Soc. Yaud. Sci. Nat., xxix. (1893) pp. 51-3. § Biol. Centrulbl., xiii. (1893) pp. 244-55. 470 SUMMARY OF CURRENT RESEARCHES RELATING TO 60 grammes. In fact the author cannot blame them for any direct damage, but, none the less, they make a house uninhabitable and life a burden. The author has much that is interesting to relate in regard to these pests, why they are called after Pharaoh, that they eat everything edible except butter, that they do not (as often reported) destroy furni- ture, and many other items of information, but he refrains from noting how they may be got rid of, which to many would be the first and last question. Change of Diet in a Beetle.* — Dr. J. Ritzema Bos notes a case in which Harpalus ruficornis F., habitually an insectivorous insect, had taken to a diet of ripe strawberries. On another occasion they visited in the evenings the beds of the country folk and bit the sleepers virulently. Reducing Division in Spermatogenesis of Gryllotalpa.j — Dr. O. vom Rath finds that up to the last spermatogenetic division but one the number of chromosomata is twelve, and that the mitoses are like those of the body-cells. But before the last division but one twenty-four chromosomata are seen in the mother-sperm-cell arranged in six groups of four. These are reduced by the second last division to the typical number (12), and by the last division to six. Four spermatozoa are formed from the mother-sperm-cell, and each contains a chromosoma from each of the six groups. A Diluvial Cockroach.f — Dr. E. Schaff describes as Perijplaneta fossilis the remains of a cockroach found by Dr. 0. Weber in an inter- glacial peat-bed in Schleswig-Holstein. The remains are exceedingly like parts of a female Asiatic cockroach. Now, if Dr. Weber be right in asserting that the insect could not have penetrated at a recent date into the peat-bed, two possible interpretations of its occurrence remain. Either the records which state that P. orientalis came to Europe about 200 years ago are wrong, or the insect lived in Europe in diluvial times, and afterwards died out. Halobatidae of Plankton Expedition^ — Dr. F. Dahl, after a short account of the typical structure of a Halobatid, has a few notes on the apparent small number of specimens and species collected in the Atlantic in 1889 during the now well-known “ Plankton Expedition.” Questions that remain to be answered regarding them are, among others, On what do they live ? do pelagic fish live on them ? how do the limbs act ? B. Myriopoda. Eye of Scutigera coleoptrata.|| — Dr. T. Adensamer shows that though the eye of this Millipede has the external appearance of a true facetted eye, it presents essential differences from the typical form. The cornea is the product of two cells ; the refractive body which lies below it, though it has the same functions as the crystalline cone of facetted eyes, has, as Grenacher has shown, a different structure ; it is made up * Biol. Centralbl., xiii. (1893) pp. 255-6. f Ber. Nat. Gesell. Freiburg i. B., vi. (1891) pp. 62-4, % Zool. Anzeig., xvi. (1893) pp. 17-9. § Ergebnisse der . . . Plankton-Exp. in 1889, Bd. ii. G. a. (1893) 9 pp. (8 figs.). || SB. Zool. Bot. Ges. Wien, xliii. (1893) pp. 8 and 9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 471 not of four, but of six cells; nuclei, which are generally persistent throughout life, are only found on these cells in quite young examples of S. coleoptrata. The crystalline body, as the structure may be called, does not, like the cone of true facetted eyes, lie in front of the nervous portion of the eye, but is largely enveloped by it. The retinal portion consists of two layers of cells, in the upper of which there are twelve, and in the lower four retinular cells, whereas the ordinary number is seven. A new Stage in the Development of Male Iulidae.* * * § — Herr C. Verhoeff found in an autumn collection of Hemipodoiulus Karachi that all the adult males had the first pair of legs hook-shaped, and were thus different from those collected in May and June, whose first limbs were leg-like. The two sets agree in form, sculpturing, colour, size, and in the characters of the anal segment, foramina, ocelli, antennae, and head ; they differ as to “ cheeks,” first pair of legs, and copulatory organs, the autumn males representing an adult stage, the spring males an inter- mediate stage (status medius or Schaltstadium). The embryological and taxonomic importance of this discovery is emphasized. 5. Arachnida. Extreme Case of Parasitism-! — Dr. R. Hessler relates a case of a partly paralysed man whose body was covered with thick scales, which literally covered him like a fish. These were found to be due to itch- mites, of which it is calculated that there were on his body two millions, while of egg-cases and eggs there were seven millions. As in an ordi- nary case of itch the number of mites does not exceed one hundred, it is clear that this may well be called an “ extreme case.” Circulatory Apparatus of Mygale csementaria.!— M. M. Causard states that the heart of this tetrapneumonous Spider resembles in many points that of other Araneidas. There are four pairs of ostia, whereas dipneumonous Araneids have three pairs, or, in rare cases, less. The heart of Mygale Blondii is stated by Blanchard to be divided into chambers ; but this is not the case in M. csementaria , where there is but a single chamber with four enlargements. There are only two pairs of pulmonary veins ; the blood is brought back to the heart by a pair of large lateral arteries, and two which are much smaller. Between the origin of these last there is a large trunk which takes a vertical course, and soon gives off backwards a branch which the author considers as corresponding to the caudal artery of other Araneids ; later on it divides into two branches which branch right and left of the digestive tube, and ramify in the posterior region of the abdomen. e. Crustacea. Cement-glands of Lobster. § — Mr. F. H. Herrick has a note on the cement-glands and origin of egg-membranes in the Lobster (Homarus americanus ). The gland appears to be limited to the five anterior pairs * Zool. Anzeig., xvi. (1893) pp. 20-6. f Amer. Natural., xxvii. (1893) pp. 316-52. t Comptes Rendus, cxvi. (1893) pp. 828-30. § John Hopkins Univ. Circ., xii. (1893) p. 103. 472 SUMMARY OF CURRENT RESEARCHES RELATING TO of pleopods, and these, for some time before oviposition, are filled with a milky-white substance. On the removal of the cuticle from a pleopod the tissue is seen to be studded with very minute round bodies, which are the cement-glands. In section the gland is composed of a very delicate sheath of connective tissue, and a simple epithelium formed of tall, pyramidal cells. The apices of the cells meet near the centre of the gland, the opening of which to the exterior it is impossible to detect. Shortly after oviposition the glands may be seen to have undergone a remarkable change in structure. They are enlarged and the epithelial cells appear to be degenerated, while the cell-outlines are very dim. Protective Adaptations in Crabs.* — Dr. V. Haecker discusses, in an interesting essay, “ the specific variation of Arthropods,” with especial reference to the protective adaptations exhibited by crabs. He begins by noticing that certain lines of variation are characteristic of certain orders and families ; thus sexual dimorphism is marvellously varied among Lamellicorns, but restricted among Caraboidea, these being notable for their protective coloration. So the Copepods are manifold in their sexual dimorphism, while the Decapoda are restricted as to this, but are notable for their protective adaptation. Rapid movement, burrowing, and masking illustrate their protective instincts. Some cases of masking have been recently studied with much care by Aurivil- lius. That the masking of Hyas, Dromia , &c., is an active process is beyond doubt. It has been repeatedly observed. On Dromia , the author found peculiar hooked hairs (noted by Aurivillius on Hyas), which make the fixing of foreign objects easier. But these are restricted in Dromia to the anterior end of the carapace and to the upper surface of the anterior limbs, for the posterior limbs in the Dromia- type have been modified so as to hold large objects on the crab’s back. It is suggested that in the history of the Dromia-type, two modes of masking — by means of hooked setae and by means of backward- turned appendages — have predominated at different epochs. Limnoria lignorum.j — The commission appointed by the Royal Academy of Amsterdam to investigate the life and work of Limnoria lignorum has given in an elaborate report. The animal’s geographical distribution, structure, and habits are discussed at length, but due attention has been given to its occurrence on the Dutch coast, the damage which it does, and the possibilities of lessening the evil. Parthenogenetic Ova of Artemia salina.J — Dr. A. Brauer finds that the directive spindle in these ova consists not of 24-26 bipartite chromo- somata, but of 84 tetrapartite elements, which are arranged not in one ring nor in two, but in a round plate. This runs counter to the results of Weismann and Yom Rath. The maturation occurs in two ways. Only one polar body may be extruded, the remainder becoming the final ovum-nucleus. Or, a second division may occur, but without extrusion, the retained half uniting its chromosomata with those of the ovum-nucleus in the first segmentation- spindle, behaving, in fact, as if it were a sperm-nucleus. In the first * Ber. Nat. Gesell. Freiburg i. B., vi. (1891) pp. 90-100. + Verh. K. Akad. Wet. Amstel., 1893, vi., 103, and xcvi. pp., 7 pis. X Zool. Anzeig., xvi. (1893) pp. 138-40. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 473 case, the ovum-nucleus contains 84 bipartite chromosomata ; in the second case it contains 84 single chromosomata. In the first case, the equatorial plate of the first segmentation spindle has 84 chromosomata, in the second case 168 ; but the second case is rarer. The larger number is the normal. It is interesting to find that the occurrence of two divisions is compensated for by the subsequent union of the second directive-nucleus with the too much reduced ovum-nucleus. Brauer’s results are in harmony with those of Boveri and 0. Hertwig in regard to parthenogenesis. Podopsis.* * * § — Mr. F. H. Herrick brings forward evidence to show that the remarkable Schizopod genus described, in 1829, by J. Vaughan Thompson as “ Podopsis,” or the Hammer-headed Shrimp, is a larva of Stenopus. No other allusion to the genus has been found by the author. Mr. Herrick points out that the form figured by Thompson is strikingly like the Stenopus- larva figured on plate xii. of his account of the Life- history of Stenopus ,j* In the enormous eye-stalks, the antennae, the huge size of the third pair of maxillipeds, the configuration of the body and of the tail-fin, there is a very close agreement between “Podopsis” and the Mastigopus-larval-stages of Stenopus hispidus. Vermes, a. Annelida. Peculiarities in Segmentation of Polychsetes.J — Miss F. Buchanan, referring to Cori’s recent paper § on abnormalities in the segmentation of Annelids, points out that there is at least one family of Polychaeta in which cases of intercalation and spiral segmentation are so common that they may be regarded rather as normal individual variations than as abnormalities. This family is that of the Amphinomidae. In fourteen specimens of the subgenus Eurythoe from Torres Straits six have each a half-segment completely or incompletely intercalated ; in Linopherus one of two specimens has two and a half of its segments arranged as a right-handed spiral. In seventeen specimens of Eurythoe from the Gulf of Manaar two have intercalated half-segments, and six have spirals of varying lengths. Of fifty specimens of Amphinome in the British Museum, twenty-seven present variations in symmetry of one kind or another ; of thirty-three examples in the same collection of the subgenera Eurythoe and Hermodice, a dozen appear to present irregu- larities in segmentation ; of these the most remarkable is the specimen in which one spiral of two coils begins in the middle of and intertwines with another of seven. Other examples are cited, including the very distant Pentasiomum , and reference is made to Cori’s observation of intercalations of half- segments in Cestodes. It is as yet too early to assign a cause to these variations, but some objections to regeneration are offered, and it is pointed out that the spiral arrangement may still require explanation. * John Hopkins Univ. Circ., xii. (1893) p. 104. f Mem. Nat. Acad. Sci., v. (1892). t Quart. Journ. Micr. Sci., xxxiv. (1893) pp. 529-44 (1 pi.). § See ante, p. 38. 474 SUMMARY OF CURRENT RESEARCHES RELATING TO Alciopidae of Berlin Museum.* * * § — Dr. C. Apstein reports that the collection of Alciopidae at Berlin consists of forty-seven specimens, be- longing to thirteen species ; of these species, Vanadis violacea , V. Studeri, Callizona Moebii , and Corynocephalus Gazellse are new. There are more or less detailed notices of the species already described. Maxillary Apparatus of Euniceidae.f — M. J. Bonnier, referring to the criticisms made by Claparede and Grube on the classification of the Euniceidae proposed by Ehlers, which is chiefly based on the structure of the upper jaw, shows that in one and the same species the two typical forms described by Ehlers may be seen at different stages of growth. The author gives an account of his observations on Ophryotrocha puerilis, where there occur successive modifications which have not till now been described. To complete our knowledge of the genus the male form must be discovered. New Organ in the Lycoridea4 — Mr. E. S. Goodrich finds that Nereis diversicolor has in every segment, except the first and last few, a pair of large, highly differentiated, ciliated patches of coelomic epithe- lium— the dorsal ciliated organs. These organs seem to occur through- out the Lycoridea, as they have been found in all the genera examined. The nephridium of N. diversicolor consists of a compact mass, per- forated by a convoluted canal, which communicates with the exterior by a short duct which leads to a nephridiopore on the ventral surface. A. long canal springs from the main body of the nephridium, and ends in front by a nephrostome which opens into the next segment ; this nephrostome is provided with long ciliated processes. The author is of opinion that the dorsal ciliated organs may be considered as a not fully developed genital duct, and he points out that the Capitellidse, which are the only other Polychaetes that are known to possess a nephridium like that of Nereis , have in many segments a large ciliated patch of coelomic epithelium, which becomes funnel-shaped, and functions as a genital duct. He thinks that recent researches point to the conclusion that in most Polychaetes the nephridium is a compound organ formed from the fusion of a tube with an outpushing of the coelomic epithelium (Meyer) ; in the Capitellidse this funnel is partly nipped off as the genital duct, while in Oligochaeta, and perhaps also the Lycoridea, this coelomic funnel has either never joined the nephri- dium at all, or is afterwards mostly or entirely separated off as a genital duct. It has been suggested by Prof. Lankester to Mr. Goodrich that primitively the coelom of Chaetopods may have been ciliated all over — as, for instance, in Bhynchobolus. If it were so the ciliated organs might have been formed by the restriction of the cilia to a definite area, and the consequent specialization of the epithelium. Arenicola marina.§ — Prof. E. Ehlers communicates some interesting information in regard to the lobworm. In a recent memoir on the “ auditory ” organs, he expressed a doubt whether the gelatinous balls * Arch. f. Naturg., lix. (1893) pp. 141-50 (1 pi.), t Comptes Bendus, cxvi. (1893) pp. 524-6. t Quart. Journ. Micr. Sci., xxxiv. (1893) pp. 387-402 (2 pis.). § Nachr. K. Gesell. Wiss. Gotting., 1892, pp. 413-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 475 described by Max Scbultze as the spawn of the lobworm were really so. This doubt had been previously expressed by Messrs J. T. Cunningham and G. A. Ramage, who reared the ova from these balls, and found that the larvae had not the characters of Arenicola , but perhaps of Scoloplos armiger. Dr. Cl. Hartlaub, in Heligoland, reared the larvae to a slightly more advanced stage, and Ehlers abandons any idea of their belonging to Arenicola. Mr. E. A. Andrews has recently described a free-swimming young Arenicola (A. antillensis ?) from the American coast. Dr. Hartlaub has also discovered this pelagic stage off Heligoland, and a brief description is given. The fishermen say that the lobworm sometimes swims freely, and Dr. Ehrenbaum has recently corroborated this statement. It seems then as if the adults led an active life for some part of the year. That the young are pelagic has been placed beyond doubt. Prof. Ehlers points out the importance of following up the quest. Supporting Tissue of the Nervous System.* — Herr E. Wawrzik finds four distinct modes in which the nerve-chord, or, more strictly, its supporting tissue, is related to the subcuticula. (1) In Sigalion , Sthenclais, Polynoe , &c , the connection persists along the entire length of the body. (2) In Holla , Cirrhatulus, Ac., the connection is reduced to a longitudinal strand. (3) In Arenicola , Eunice , &c., the connection is by means of relatively thin strands, which occur at intervals. (4) In Hermione, Aphrodite , and the Oligochasta the subcuticular fibrous tissue has formed a cuticular membrane surrounding the nerve-cord and separating it from the subcuticula, except at the tail end. At different parts of the body different modes may obtain. The supporting tissue is a modification of the subcuticula ; it not only ensheaths the nervous elements, but penetrates them, passing into their spongioplasma. New Species of Nais.f — Dr. W. B. Benham has a note on a new species of this genus, found in a ditch near Oxford ; N. Jieterochseta, as it is called, has, as a rule, only two chaetae in each dorsal bundle ; and these are of different shape and size ; one is capilliform and about *165 mm. long, and the other is furcate and measures *045 mm. The nephridia present a peculiarity which, though already described, has hardly been sufficiently insisted on ; the fact, that is, that there is usually only one nephridium per somite. This is always the case in N. heterochseta, where the nephridium is very long, so that one often occupies two somites, and communicates with a third by a funnel. In such cases there is one nephridium in the place of four. Michaelsen, it will be remembered, has described in Kynotus the presence of nephridia in alternate somites. Anatomy of Sutroa.J— Mr. F. E. Beddard has some notes on this freshwater Oligochaste, supplementary to the description of Dr. Eisen, who alone has before this worked at the genus. The author has chiefly directed his attention to the generative organs which he has investigated * Zool. Beitr., iii. (1892) pp. 107-27. t Quart. Journ. Micr. Sci., xxxiv. (1893) pp. 383-6 (1 pi.). X Trans. Roy. Soc. Edin., xxxvii. (1893) pp. 195-202 (1 pi.). 2 L 1893. 47 G SUMMARY OF CURRENT RESEARCHES RELATING TO by means of the section method. The efferent apparatus, while con- structed on the Lumbriculid plan, has prostates which suggest those of the Tubificidse more than those of other Lumbriculid ee. The anterior pair of funnels and the vasa deferentia are so reduced as to suggest a commencing disappearance; were they absent, the structure of the reproductive organs would be those of the Tubificidae. Mr. Beddard suggests that Dr. Eisen has overlooked the testes, and has mistaken for them peculiar bodies that may be compared with the “ septal sacs ” of many Perichaetidae and of Acanthodrilus. A number of segments have no nephridia. New Moniligaster.* — Dr. W. B. Benham describes a new species of Monilig aster (M. indicus ) from the Nilgiris, which agrees with none of Prof. Bourne’s species in the few characters given by him. The author takes the opportunity of remarking that the position of the various genital pores in Moniligaster were wrongly given by him in his “ Attempt to classify Earthworms.” As various recent writers have pointed out, this octochaetous meganephric genus has the male pores between somites x. and xi., a single pair of spermathecal pores between somites vii. and viii., a pair of oviducal pores between somites xi. andxii., and the nephri- diopores in line with the dorsal couple of chastae. He also points out the distinctive internal characters of the genus, and, after indicating briefly seven diagnostic points in M. indicus , gives a detailed account of its anatomy. Notes on Hirudinea.f — Dr. R. Blanchard has a notice of Theromyzon pallens described by Philippi in 1867, which he suggests is merely Glossijplionia bipunctata. The Hirudo Nais of Grube is shown J to be the representative of a new genus which may be called Mesobdella , as it unites the characters of the Glossiphoniidae with those of the Hirudinidae. Some notes are given § on variations in the constitution of the somite of Leeches ; in some cases there is a tendency to the multiplication of rings, which appears to be most extreme in the case of Lumbricobdella scliaejferi Kennel which has 262 rings. In his tenth note || Dr. Blanchard makes some observations on the Hirudinea of northern Europe ; this group is very rare in boreal regions, and he enumerates only five : — Esemopis sanguisuga , Glossiphonia biocu- lata , G. sexoculata, Placobdella Eaboti, and P. Guernei ; the last two are new species, and belong to a new genus, which, with a close resemblance to Esementaria , is distinguished by the absence of a deep transverse groove from the ventral surface of all the rings. The new genus has also some affinities with Glossiplionia, which it brings into closer alliance with Esementaria. In this same new genus ^ Dr. Blanchard places the Glossiphonia catenig era of Moquin-Tandon, and the Clepsine carinata** of Diesing, of both of which he gives full descriptions. * Quart. Journ. Micr. Sci., xxxiv. (1893) pp. 361-82 (1 pi.), f Bull. Soc. Zool. France, xviii. (1893) pp. 14-6. j Tom. cit., pp. 26-9 (4 tigs.). § Tom. cit., pp. 30-5 (4 figs.). || Tom. cit., pp. 92-8 (5 figs.). Tom. cit., pp. 98-104 (5 figs.). ** Tom. cit., pp. 104-8 (2 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 477 j3. Nemathelminthes. Germinal Zone of Ascaris megalocephala.* — Dr. von Wasielewski lias traced the genital tubes to their ends where they form a very fine coil. A simple membrane encloses a single row of large germ-cells. Lower down the membrane shows a plasmic layer and nuclei. Between the germ-cells and the membrane a distinct cellular layer is formed and the central germinal cells cease to be in a single row. In the centre the rhachis appears as a plasmic pillar. Even in the large cells of the single row the equatorial plate stage of karyokinesis was detected. The chromatin threads fall into cubical elements with each of which a spindle thread is associated. Sometimes these cubes divide and what looks like a double row of pearls is seen along the equator. The genital tubule includes, at some distance from its origin, a number of large cells of unknown origin and import. There are also residual bodies, which Lameere regards as due to extrusions of nuclear substance from the differentiating sex-cells. But they are least abun- dant where cell-multiplication is most active. The author regards them as the results of the degeneration of germ-cells in consequence of pressure and imperfect nutrition, and compares them with degenerations in the testicular canals of man in cases of local tuberculosis. Oxyuris Paronai and Cheiracanthus hispidus.j — Dr. von Linstow describes a new species of Oxyuris found on Branco, one of the Cape Verde Group, in Macroscincus Coctei , and he enters at length into an account of Fedtschenko’s species Cheiracanthus hispidus, sixteen specimens of which were found in the stomach of a Hungarian Pig. y. Platyhelminthes. Turbellarian in Underground Waters.^ — Prof. W. A. Has well reports an alloiocoele Turbellarian as inhabiting the underground waters of Canterbury, New Zealand. With two exceptions, one of which is very doubtful, all the members of this group are sea-dwellers. All the specimens examined by the author are devoid of eyes and completely destitute of pigment ; the largest are nearly an inch and a half long. Further details are promised. New Genus of Temnocephaleae.§ — Prof. W. A. Has well has a preliminary note on Actinodactylus , a new genus allied, at first sight, to Temnocephala , but having twelve tentacles and no eyes ; it was found in the branchial cavities of the burrowing land-Crayfish of Gippsland ( Engseus fossor). In living examples the difference between it and Temnocephala is much more marked than in alcoholic specimens. Marine Planarians of New England |] — Prof. A. E. Verrill has brought together the scattered notes, descriptions, and sketches of the marine planarians of New England, made during more than twenty seasons of work at marine Invertebrates. He does not expect his paper to serve more than as an introduction to the study of a group, which has been much neglected by American naturalists. The author points out * Arch. f. Mikr. Anat., xli. (1893) pp. 324-37 (1 pi.). t Arch. f. Naturg., lix. (1893) pp. 201-8 (1 pi.). t Proc. Linn. Soc. N.S.W., vii. (1893) pp. 341 and 2. § Tom. cit., p. 342. [| Trans. Connect. Acad., viii. (1892) pp. 459-520 (5 pis.). 2 l 2 478 SUMMARY OF CURRENT RESEARCHES RELATING TO the extreme difficulty of determining alcoholic specimens, and urges that species should be studied as fully as possible while living, and preserved as microscopic preparations to show their anatomy. Eustylochus (for Planocera elliptica Girard) is a new genus which, externally, agrees with Stylochus, but differs in the structure of its repro- ductive organs ; Planoceropsis is a new subgenus of Planocera with marginal ocelli. The number of new species is hardly as large as one might have expected. Dinophilidae of New England.* * * § — Prof. A. E. Yerrill describes two species which appear to be the only known representatives of this group on the New England coast. He calls them DinopMlus pygmseus and D. simplex , though they differ considerably in structure ; the latter may not be a true Dinophilus. Marine Nemerteans of New England and adjacent Water s.t — Prof. A. E. Verrill offers an article which is intended as a descriptive catalogue of all the Nemerteans of the north-eastern coast of North America that have been observed with enough care to permit him to give a description presumably sufficient to enable ordinary observers to identify the species when seen living. He particularly notes any of the few cases in which descriptions have not been made from living speci- mens. As a rule, undetermined alcoholic specimens of Nemerteans, unaccompanied by notes on their forms and colours while living, cannot be identified with certainty, unless they belong to genera which contain very few and widely differing species. The author has had to do with collections which include several thousands of specimens, and which represent very fully the Nemertean fauna of the coast from Cape Hatteras to Labrador, and from high-water mark to 2000 fathoms. These worms are much more abundant from 1 to 60 fathoms than at greater depths. The only two remarkable new forms described are examples of pelagic Nemerteans, taken in the region of the Gulf Stream. In form they resemble Sagitta, but they are much larger and stouter, and the general organization is not very different from that of the typical Enopla. The author forms, however, a new family for them, which he calls that of the Nectonemertidae. With some affinity to Pelagonemertes they differ by their form, distinct head, caudal fin, and absence of much subdivided intestinal diverticula. The two new genera are called Nectonemertes (for N. mirabilis sp. n.) and Hyalonemertes (for H. atlantica sp. n.). Nemertea of Lake Geneva. J — Dr. G. du Plessis points out that Mr. L. Vaillant is wrong in asserting that the Nemerteans discovered by du Plessis in Lake Geneva belong to the genus Geonemertes. For the forms in question are wholly aquatic, are provided with cephalic slits and lateral organs, have separate sexes, and so on; they are certainly not related to Geonemertes. They are of much interest as forming part of a “ Fauna relicta.” Reproduction of Geonemertes australiensis.§ — Dr. A. Dendy reports that the eggs of this worm are about 0 • 6 mm. in diameter, and * Trans. Connect. Acad., viii. (1893) pp. 457 and 8 (2 figs.). t Tom. cit., pp. 382-456 (7 pis.). X Zool. Anzeig., xvi. (1893) pp. 19-20. § Proc. Koy. Soc. Victoria, 1892, pp. 127-30 (from separate copy). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 479 of a white or nearly white colour. Some thirty are enclosed together in a sausage-shaped mass of colourless transparent jelly ; this jelly appears to be common to all the eggs and does not, as in the case of frog-spawn, form a special envelope round each. The eggs probably leave the body separately by the narrow duct which serves also for the admission of the spermatozoa. The author thinks the jelly is a secretion from the surface of the body. British Marine Turbellaria.* — Mr. F. W. Gamble finds that at present there are known as members of the British fauna fourteen Poly- clads, two Triclads, and fifty-five Bhabdocoels ; these he describes, giving the distinctive structural and bionomical points. It is, however, to be noted that these numbers represent the examination of a limited extent of the English coast, the Channel Islands, and the Isle of Man during three months of summer (July to September). The author has increased the number of British species by twenty-eight, of which Provortex rubro - bacillus , Plagiostoma pseudomaculatum , P. elongatum , and Automolus Jiorridus are new species. The faunistic relations of our Turbellaria cannot yet be certainly determined, but it is clear that a large proportion of Scandinavian forms occur, and 33 per cent, are common to Naples, Plymouth, and Trieste. In the investigation of the British Turbellaria there is obviously ample work for the students of minute forms. Cercaria of Amphistomum subclavatum.f — Dr. A. Lang has dis- covered that this well-known Trematode ( Diplodiscus subclavatus Dies.), not unfrequently found in the rectum of Amphibians, has Planorbis contortus (L.) Mull, for its intermediate host. No sporocysts were found, which suggests that the rediae (in summer at least) arise directly from the embryos. The Cercariae leave the snail by the rectum, swim about, attach themselves to the skin of amphibians and become encapsuled. It is likely that they are swallowed along with portions of cast skin. Experiment showed the efficiency of this mode of infection. The author also gives an account of the structure of the Cercaria, especially of the excretory system, which has not hitherto been described in detail. Anatomy of Caryophyllseus mutabilis-t — Kerr H. Will has made an investigation into the structure of this interesting Cestode. The absence of proglottids and the simplicity of the sexual apparatus are sufficient to show that it occupies an important position as a primitive form. But even here there are intermediate stages. Although it is true that the Ligulidae, when sexually mature, exhibit a formation of proglottids with a repetition of the parts of the sexual apparatus, yet it is doubtful whether isolation is carried as far as in the Bothrio- cephalidae, while the proglottis of the latter by no means attains the stage of individuality seen in Taeniae. In the nervous system, the two primary trunks which traverse the whole length of the animal, and are connected with one another a short way behind the head by a dorsal and a ventral transverse commissure, are common to it and other Cestodes. In addition there are dorsal and * Quart. Journ. Micr. Sci., xxxiv. (1893) pp. 433-528 (3 pis ). t Ber. Nat Gesell. Freiburg i. B., vi. (1892) pp. 81-9 (1 tig.), t Zeitsohr. f. wiss. Zool., lvi. (1893) pp. 1-39 (2 pis.). 480 SUMMARY OF CURRENT RESEARCHES RELATING TO ventral paired secondary nerves, which, by the whole of their structure, show a primitive similarity to the primary trunks. The nervous system consists, therefore, of six longitudinal nerves, which stand at pretty regular distances, and are connected with one another by circular com- missures ; this arrangement agrees completely with the Trematode type. In other Cestodes the secondary nerves have more or less disappeared, though remnants of the same are generally found in the head and neck. By Trisenophorus nodulosus the excretory system of Caryophylleeus is linked on to that of other Cestodes. A point of structure apparently quite peculiar to our worm is the presence in the median layer of three or four longitudinal cords formed of fibrous cells. These are not found in other Cestodes, unless, indeed, they are represented by the layer of spindle- cells described by Leuckart in Tsenia saginata. With regard to its generative apparatus C. mutabilis appears to represent a primitive stage, and to be nearest to the Bofchriocephalidae. The male and female apparatus lie behind one another, while the yolk- glands are in the median layer. In the Botliriocephalidse the male and female generative apparatus lie one above the other, and the yolk-glands are in the cortical layer ; this appears, however, to be a secondary con- dition due to the necessities of space and packing. Further, in C. muta- bilis, the uterus opens together with the vagina, and this appears to be a unique arrangement amongst Cestodes ; it may, nevertheless, be con- sidered to be a starting point, for if the uterus separate from the vagina and open separately we have the type of the Bothriocephalidae, while in the Taeniidse the terminal portion of the uterus is degenerated, and the true uterus ends blindly. We may conclude, then, that in three points — its unsegmented body, its nervous system, and the structure of its generative apparatus — Caryojphylleeus occupies a primitive position. Helminthological Notes.* — Dr. M. Stossich has notes on species of Ascaris and Heterakis, Dispharagus laticeps, species of Filar ia, Spiropterina dacnodes, Agamonema Ranzanise Stossich, Physaloptera clausa , Oxysoma brevicaudatum , species of Echinorhynchus , species of Tsenia, Phyllobothrium laciuca , Bothriocephalus Wageneri, Holostomum variabile , and Distomum italicum Stossich. Stossich also gives f a revision of the genus Angiostomum Dujardin, recognizing five species which live in the lungs of birds, reptiles, and amphibians. 5. Incertse Sedis. Irish Rotifers.:}: — Miss L. S. Glascott gives a list of some of the Rotifera of Ireland. As the research extended over only six months and a number of rare and new species were obtained, it seems j>robable that this group is well represented in that island. In describing her captures Miss Glascott very properly follows the order of Dr. Hudson and Mr. Gosse’s book. The following list gives the names of the new species: — Rotifer phaleratus (“probably only a variety of R. vulgaris”). Microcodon (?) robustus, Notops (?) quadrangularis , Notommata volitans , * Boll. Soc, Adriat. Sci. Nat., xiv. (1893) pp. 83-9. f Tom. cit , pp. 90 G. X Sci. Proc. Royal Dublin Soc., viii. (18'j3) pp. 29-86 (7 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 481 N. cylindriformis, N. larviformis, N. rubra , Furcularia semisetifera, F. megaloccphala , F. rigida , Eosphora striata (large and conspicuous), Diglena inflata, D. revolvens, D. elongata , D. rugosa, Mastigocerca brachy - dactyla, Colurus pacliypodus , and C. tessellatus. As “ later additions ” we have Notops forcipata , Notommata lucens, N. gigantea, Diglena Hudsoni , and D. dromius ; the last, which is said to be very slender and graceful, has manners which “ amusingly resemble those of some of the predatory beetles.” Rotatoria of Greenland.* — Dr. D. Bergendal gives an account of the rotifers collected during a visit to Greenland in 1890 ; he enumerates altogether eighty-two species, of which a number are new. Of the three new genera Microcodides ( M . dubius sp. n.) wants the foot which is so characteristic of Microcodon , but in all other respects there is a great resemblance between the two genera. Hypopus ( H . Bitenbenki sp. n ) is a new genus of Notommatidse, which the author for some time thought to be the same as Hudson’s Notops hyptopus ; Hudson’s species is to be referred to the new genus, the affinities of which are rather with Notom- mata than Hydatina. The third new genus Diops is established for D. marina sp. n., which some may think to be a Furcularia or a Diglena ; there is a double frontal eye and the mastax has no fulcrum. The author describes his forms in ample detail. From his concluding remarks it is clear that he does not think he has exhausted the points of interest in the Rotiferous fauna of Greenland. Rotifera of the Gulf of Naples.! — Dr. E. v. Daday studied at Naples twelve species of Rotifers, including Furcularia neapolitana sp. n., Colurus rotundatus sp. n., and C. truncatus sp. n. Six of the twelve were already known from other seas. In all cases saccular salivary glands were found between gullet and gizzard, or beneath the gizzard. Some forms have ovary and yolk-gland, while others have also a uterus. No fertilized thick-shelled ova were found, and no males. Perhaps the conditions of marine life are normally such that neither are necessary to the continuance of the species. From the Baltic 50 species are known, from the North Sea 3, from the Mediterranean 13, from the Adriatic 2, from the Indian Ocean 2, and from the Pacific 1. Of marine forms, 20 are free-living and 8 parasitic ; 5 species occur in the seas, in fresh water, and in inland seas ; 32 species occur both in fresh and salt water. The Rotifer fauna of inland salt water and of brackish water is to be regarded as transitional between freshwater and the sea. The author believes that Rotifers as we know them are secondarily marine and primarily freshwater organisms, though it is likely enough that their ancestors were originally marine. New Freshwater Rotifers.f — Profs. A. Wierzejski and 0. Zacharias describe three species — Bipalpus vesiculosus W. and Z., Bipalpus lynceus Ekrbg. (? Euchlanis lynceus Ehrbg.), and Mastigocerca capucina W. and Z. Of the first only the female form was studied, but the male was seen. The female has a sack-shaped body, rounded posteriorly, truncate in * Acta Univ. Lundensis, xxviii. (1892) IV. 180 pp. (6 pis.). f Math. Nat. Ber. Ungarn, viii. (1891) pp. 319-53; Math. Termes. Ertes. (Math. Nat. Anz. d. Akad.), viii. pp. 4-8. X Zeitachr. f. wiss. Zool., lvi. (1893) pp. 23G-44 (1 pi ). 482 SUMMARY OF CURRENT RESEARCHES RELATING TO front ; the crown has a simple wreath of cilia and two lateral ear-lobes, each with a finger-shaped palp with a hint of segmentation ; on the middle field of the crown are eight bluntly conical prominences with sensory hairs ; the foot is borne ventrally at the beginning of the posterior third of the body ; the eye is simple and occipital ; the mouth- parts have weak jaws, the hypodermis is vacuolar ; there is a Y-shaped thickened shield on the back. Of the third species, only the female is known. It has an almost cylindrical body, a distinctly defined head, a characteristic cap-like head-shield, a crown with five finger-like palps and two sensory tufts, and lateral antennae on the posterior third of the body. Adinetidae.* * * § — Mr. D. Bryce has some general notes on this group of Rotifers ; in moss-washings no species is of such general occurrence as Adineta vaga , on which his observations have been chiefly based. He describes A. clauda sp. n. from a single specimen obtained at Gareloch- head, N.B., where it lives in moss. By its sucker-like foot it is allied to Discopus, and perhaps it is the type of a new genus. Notes on Rotifers.} — Mr. G. Western finds that his Pleurotrocha grandis is synonymous with Diglena ferox. Philodina commensalis sp. n. was found on Asellus vulgaris from Putney, Wandsworth, and Epping Forest. Mr. Hood has sent the author examples of the male of Stephanoceros Eichhorni , ’which has never yet been recorded. Notholca Hoodi sp. n. was taken in sea water at Westport, Ireland ; Pattulus bicornis sp. n. was found at Roehampton, and is common in Scotland and Ireland ; Callidina sordida sp. n. is a large form, which was found in moss that came from Epping Forest. Phoronis from Port Jackson.} — Prof. W. A. Haswell reports that, in addition to the large Phoronis australis which he described eleven years ago, he has lately found a smaller species of the same rare genus, in which he can find hardly any point of importance to separate it from P. psammophila from Messina; the most important distinctions are the greater number of tentacles (about 100), and the absence of sand-grains from the tubes. Minute Anatomy of Rhodope Veranii.§— Dr. L. Bohmig treats in detail of the minute anatomy of this much discussed organism. In his opinion the facts of its development are opposed to its being one of the Mollusca, while those of its structure support the view. On the other hand, if we compare it with the Turbellaria we find it has a digestive apparatus which consists of three portions and opens by an anus which is placed on the right ; the central nervous system is broken up into a pair of cerebrovisceral ganglia, a pair of pedal and a pair of buccal ganglia ; three commissures surround the fore-gut. The excretory system is without the ciliated infundibula which are characteristic of the Piatyhelminthes, and, in position and structure, is much more like that of the Nudibranchiata ; the chief part of the genital organs is repre- * Journ. Quek. Micr. Club, v. (1893) pp. 146-51 (1/2 pi.). t Tom. cit., pp. 155-60 (1/2 pi.). } Proc. Linn. Soc. N.S.W., vii. (1893) pp. 340 and 1. § Zeitschr, f. wiss. Zool., lvi. (1893) pp. 40-116 (4 pis.). ZOOLOGY AND 130TANY, MICROSCOPY, ETC. 483 sented by a hermaphrodite gland, and in its general structure the generative apparatus has a striking resemblance to that of certain embryonic Gastropods. It cannot, however, be denied that, in many essential points, Rhodope does not exhibit a Molluscan organization. The blood-vascular system, the heart, the foot, the shell, are as much wanting in the embryo as in the adult ; and there is no velum. It is more doubtful what stress is to be laid on the absence of a radula. On the whole, then, we may say that Rhodope is anatomically most allied to the nudibranchiate Gastropods, while in its developmental history it is connected with the Turbellaria. At present it would seem to be impossible to assign a precise systematic position to this creature, and it would be well if a close study could be made of its embryology. The only thing we can say with certainty is that Rhodope is not a Turbellarian. Gastrotricha.* — Dr. F. v. Wagner gives an account of what is known (through Zelinka and others) in regard to these small organisms. They are small worm-like animals, without a retractile rotatory apparatus at the anterior end ; with two ciliated bands along the whole ventral surface ; with two coiled water-vascular canals, each with a long rod- like ciliated lobe and a separate aperture in the middle of the ventral surface; with a simple cerebral ganglion in part still in the ectoderm, simple muscle-cells, paired ovaries, a muscular, nematode-like, fore-gut without jaws, a straight mid-gut without glands, a pear-shaped hind-gut, a rectum, and a dorsal anus ; and with a primary bo ly-cavity. The sub- order Euichthydina (with a forked tail) includes Ichtkydidae (without spines), viz. Ichthydium and Lepidoderma, and Chaetonotidse (with spines), viz. Chsetonotus and Chsetura. The suborder Apodina (without a forked tail) includes Dasydytes and Gossea. After weighing opinions, the author concludes that the Gastrotricha cannot be united with Rotatoria, but that they belong to a common stock and are nearly related. Echinoderma. Development in Asterina gibbosa.f — Mr. E. W. MacBride has a preliminary notice of his observations on the development of the dorsal organ, genital raehis and genital organs in this Starfish. His studies have confirmed the accuracy of his earlier observations on Amphiura squamata. The axial sinus of the starfish into which the stone-canal opens is obviously homologous with the relatively less developed ampulla of the Ophiurid ; in both animals the peculiar cells of the dorsal organ are derived from the peritoneal epithelium, but subsequently by a process of invagination become shut off from it ; hence the so-called axial sinus of Amphiura corresponds to the canal in the dorsal portion of the “heart” of Asterina. The aboral sinus is homologous, and its undulating course in Amphiura is evidently due to the way in which the abactinal surface has grown in between the actinal radii in Ophiurids ; this mode of growth forces the madreporite and the stone-canal round to the ventral side, while the aboral sinus is pulled out into five inter- radial ventral loops. * Biol. Centralbl., xiii. (1893) pp. 223-38. f Zool. Anzeig., xvi. (1893) pp. 169-73 (4 figs.). 481 SUMMARY OF CURRENT RESEARCHES RELATING TO The author traces the genital cells back to the epithelium lining the canal which represents the most aboral portion of the dorsal organ, while this last has a cavity which, at an early stage, communicates with the coelom ; its epithelium, therefore, is peritoneal epithelium. From this it follows that in both Amphiura and Asterina the genital cells are, ultimately, derived from the peritoneum, or, in other words, they have the same origin as the sexual cells of all Coelomata. Cleavage of Eggs of Arbacia.* — Dr. J. Loeb has experimented on the dividing eggs of Arbacia by exposing them to water containing more or less than the normal amount of sodium chloride. If the irritability of the protoplasm of the egg be reduced by reducing the amount of water contained in it, the nucleus can segment without segmentation of the nucleus. If we now increase the quantity of water the protoplasm at once divides into about as many cleavage cells as there are preformed nuclei. The effect of salt is not to destroy but to suspend the cleavage phenomena ; the longer eggs are kept in concentrated water the more numerous are the cleavage cells formed all at once when the egg is returned to normal water. It would appear that the nuclei increase in numbers in salted sea-water, though no cleavage furrows are visible on the outside of the egg, but this increase is not always accompanied by a normal separation. The normal source of the stimulus which the abstraction of water is supposed to render no longer efficient to produce cleavage is supposed to be the nucleus, but the nature of this stimulus is unknown ; there are some reasons for believing it to be of a chemical nature. On the other hand, the protoplasm has some influence on the nucleus ; and it is suggested that the intracellular pressure which determines the form of the cells also fixes the direction of the nucleus. Crinoids from Sahul Bank.t — Prof. F. Jeffrey Bell has a note on a small collection of Crinoids from the Sahul Bank, North Australia. The only stalked form in the collection is Metacrinus interrupts P.H.C., taken from a telegraph wire from about as many degrees south of the equator as the type was north of the line. Evidence is afforded as to the very considerable range of variation in the length of the cirri of Antedon longicirra P.H.C. ; A. Wood-Masoni is a new species of Car- penter’s Spinifera- group ; A. patula P.H.C. was also in the collection, and it is hinted that it, A. flexilis and A. robusta, which were all taken at the same station by the * Challenger,’ may not be as distinct as is at present supposed. Holothurians from the Eastern Pacific.^ — Prof. H. Ludwig has a preliminary notice of the Holothurians collected by the ‘ Albatross ’ deep-sea expedition to the Eastern Pacific. Forty-six species belonging to twenty-eight genera were collected ; the most interesting forms are the representatives of a group intermediate between the Aspidochirotas and the Elasipoda and a rare Holothurian adapted to a pelagic life. Several examples were obtained of Theel’s Pseudostichopus mollis ; the investigation has resulted in an alteration of the generic diagnosis. * Journ. Morphol., vii. (1892). See Amer. Natural., xxvii. (1893) pp. 398 and 9. t Journ. Linn. Soc. London, xxiv. (1893) pp. 339-11 (2 pis.). j Zool. Anzeig., xvi. (1893) pp. 177-86. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 485 More than seventy examples of the same author’s Pselopatides confundens were taken, and Benthodytes gelatinosa of Walsh is found to belong to the same genus, if the diagnosis be amended to contain forms with fifteen tentacles. The two genera just mentioned have no tentacular ampullae, and in this point three new genera of Aspidochirotae — Synal- lactes, Mesites , and Meseres — agree with them ; the first may be grouped together in the sub-family Synallactinae, while the remaining Aspido- chirotae form the Holothuri[i]nae. As the former sub-family exhibits points of affinity to the Elasipoda the author notes with satisfaction the confirmation of the view already expressed by him that the Elasipoda are descendants of the Aspidochirotae. Of the six Elasipod Psychropotinae, Benthodytes incerta, Psychropotes raripes , P. dubiosa, Euphronides tanneri, and E. verrucosa are new. Of the eight Deimatinae six are new, and for some of them new genera are formed — Scotodeima ( S . setigerum ) stands between Oneirophanta and Orphnurgus , Lsetmophasma (L fec.undum) is perhaps nearest to Pannychia, Capheira (O. sulcata') is placed with some doubt among the Deimatinae. Of the sub-family Elpidiinae one is a variety of Peniagone vitrea P. intermedia sp. n. is allied to Scotoanassa , and Scotoanassa gracilis is a new species. But of all the most interesting is the pelagic creature which forms the type of the new family Pelagothuriidae. It is distinguished by the development of a special swimming apparatus, which consists of a disc drawn out at the margin into long rays ; this is arranged round the circlet of tentacles, and calls to mind somewhat the base of the arms of a Cephalopod. There are no podia or ambulacral papillae ; the mouth and anus are terminal ; the body is circular. The tentacular canals arise from the well-developed radial canals, and each sends off a canal into the disc ; these disc-canals pass in a radial direction to the periphery of the disc, and extend to the tip of each ray. The longitudinal muscles of the body-wall are simple, and there are no retractors to the pharynx. There are no respiratory trees, ciliated organs, or organ of Cuvier. In the genus Pelagotlmria , which has thirteen to sixteen tentacles, there is no sign of any calcareous deposits. There is a single stone-canal, which opens directly to the exterior. The species P. natatrix is violet or purple in colour, 47 mm. long, while the length of the disc-rays is 50 mm. In the want of podia the Pelagothuriidae agree with the Synaptidae and Molpadiidae, from each of which they differ by some of the points already noted. Prof. Ludwig regards this new group as derived from the Elasipoda and as having become adapted to a pelagic mode of life. Of the nine species of Dendrochirotae seven are new, and for one a new genus, Sphserothuria, has to be formed. S. bitentaculata has an almost spherical form, and is covered with large plates, from each of which a strong freely projecting spine proceeds. The pair of tentacles which, in decaehirote forms, is generally smaller than the other four has completely disappeared, and of the remaining eight six are much shorter than the one right and one left one that are alone well developed. The podia are uncommonly small. Sphserothuria would appear to be derived from the Echinocucumis group of Cucumaria. Four of the six Molpadiidae are new, and belong respectively to the genera Caudinn , Trochostoma and Anlcyroderma. The family Synaptidm 486 SUMMARY OF CURRENT RESEARCHES RELATING TO is represented by fragments of Theel’s species Synapta abyssicola , but there is enough of them to show that they should be marked as a variety, which may be called pacifica. Ccelentera. Development of a Palaeozoic Poriferous Coral.* — Mr. C. E. Beecher gives an account of Pleurodictyum lenticulare, a species which represents one of the simpler types of poriferous corals. The nepionic stage is well marked, and comprises the growth of the corallum to the comple- tion of a simple initial cell. In this stage there are no mural pores, and there is an epitheca over the entire exterior of the cup. The septal lines become developed towards the end of this stage. These features are in harmony with the young of many palaeozoic corals, and indicate a primitive, simple, and imperforate ancestry for the Perforata. The first nealogic stage, represented by the primitive co^allite with one bud, is the first transition towards both a compound and a perforate coral. At this stage we are reminded of Aulopora. The basal epitheca limits the fleshy portion of the organisms, and represents an area unfavourable to the acquisition of food, or for the natural development of calices. This would prevent both the maintenance of mural pores and the growth of basal buds. The author thinks that we may conclude that the mural pores in such genera as Favosites , Striatopora , Pleurodictyum , Michelinia , and others are ineffectual attempts at budding, resulting only in the perfora- tion of the cell-walls. As Yerrill has shown that the presence or absence of tabulae is of little or no importance in a natural classification, the non-tabulate nature of P. lenticulare is of no special consequence in a discussion of the relations of this species with Favosites or other tabulate poriferous genera. If Mr. Beecher’s views are correct a simple conical imperforate protocorallum may be assumed for the Madreporaria Perforata. The next stage has the structure and growth of Aulopora , and consists of the parent cell with one or more buds. Aulopora may, then, be con- sidered as representing a primitive type of a poriferous coral, in which the number of pores in each corallite corresponds with the number of buds plus one connecting it with the parent cell. It seems that, pr imarily, the development of mural pores is identical or homologous with the pro- cess of gemmation. Symmetrical Cell-development in Favositidae.f — Mr. C. E. Beecher is of opinion that the growth of intermural buds compensates for the natural divergence of the corallites. New cells are introduced wherever the old corallites have reached their maximum size, and when their divergence approaches a separation of the cell-tubes. The buds have at first the form of a triangular pyramid or prism, which is due to the mechanical conditions of growth. As they increase they touch or trun- cate one another, and change from triangular to five- and six-sided prisms. Completely symmetrical normal development produces a corallum with equal hexagonal calices. The process of intermural * Trans. Connect. Acad., viii. (1893) pp. 207-14 (5 pis.), t Tom. cit., pp. 215-9 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 487 gemmation changes the sides of the parent cells to angles, and the older corallites, originally in juxtaposition, become separated from one another by new series of interstitial calices. Affinities of Madrepora.* — Mr. G. Brook points out that this genus, with its axial corallites and radial bud-corallites, stands alone ; so far as he is aware no other genus approaches it in its mode of colony-formation, taking into account the indirect means by which it is attained, and the consequent absence of true coenenchyma. It is to be noted, however, that the characteristic mode of colony-formation is confined to the formation of independent branches, and that at first in all colonies, and always so long as incrustation continues, the mode of budding is not characteristic. It appears, therefore, reasonable to suppose that the species of Madrepora form a specialized group which indicate their affinities in the incrusting stage. For the present the author adopts the course suggested by Ridley, and divides the Madreporidae into two sub-families — the Madreporinae, with the genus Madrepora , and the Montiporinae with the genera Ana- cropora and Montipora. For a final decision we must wait till we know much more than we do now with regard to the structure of the polyps and their relation to the skeleton which they produce. Edwardsiae .f — Dr. A. Appellof, after remarking that the external division of the body into three parts, the absence of a pedal disc, the structure, position, and number of the septa are peculiarities of the Edwardsiae that have already been sufficiently noticed by preceding writers, calls attention to some other points of importance. He lays stress on the presence of an ectodermal nervous system on the capitulum ; this offers an intermediate stage between the Hexac- tiniae on the one hand and the Cerianthidae and some other forms on the other. The remaining part of the body of an Edwardsia — with the exception of the hinder end — has a thick investment, so that it is not adapted for the reception of external influences. It is not clear whether or no a nervous system is developed in the physa. On the other hand the ectodermal musculature which is developed on all other forms that have a nervous system on the body- wall is wanting in the Edwardsiae. Some attention is given to the tubercles set in rows on the surface which are peculiar to some, and perhaps to most Edwardsiae. Another point worth notice is the absence, in the Edwardsiae, of some arrange- ments which are frequently found in other Actinians. The pharyngeal grooves are either absent or are very feebly developed. Boveri has, on embryological grounds, regarded Edwardsia-like animals as the stem- forms of all other Actiniae. The want of a slightness of differentiation in the oesophageal tube appears to agree well with this conception, as it may be supposed that the tube of the stem-form was a simple invagina- tion without specially developed parts. The absence of septal stomata is, perhaps, common to all Edwardsiae, and the point is of importance since, so far as we know, internal septal stomata at least are found in all Hexactiniae-Zoanthinae. In this as in other points the tribe Protantheae, lately established by Carlgren, shows * Journ. Linn. Soc.. xxiv. (1893) pp. 353-60. t Bergens Mus. Aarsberet. for 1891, No. 4 (1892) 32 pp. (3 pis.). 488 SUMMARY OF CURRENT RESEARCHES RELATING TO a relation to the Edwardsise. In both there are only eight complete septa; both have, in the body an ectodermal nervous and muscular layer and both want acontia. On the other hand there is a difference between the two groups in the development of the ciliated bands of the mesenterial filaments ; for in Edwardsia earned they are very well developed, while in Protanthea they are wanting. Enquiry must still be made as to the conditions that obtain in other species of Edwardsia. The development of a parietobasilar muscle in the Protanthese agrees with their sedentary mode of life ; it is wanting in E. earned. Norwegian Pennatulida.* — Mr. J. A. Greig gives a list, with his- torical and bibliographical prefaces, of the Pennatulida of Norway ; twenty-nine species are recognized in it, and synonymical and other notes are generally given. Organs of Relation of Hydromedusse.f — Dr. M. Chapeaux has made an attempt to reconcile the very divergent views of authors with regard to these organs. From his experiments on the fresh- water Hydra he comes to the conclusion that sensibility is distributed all over the body, that the peristomial region near the gastrovascular orifice functions as a co-ordinating centre for movement, that the extremities of the tentacles are particularly sensitive, and that the cnidocil is a sensory element. He next describes his histological observations on Hydra , Laomedea , Podocoryne , Myriothela , and Tubularia, which have resulted in the discovery of facts which show that Hydra is not, as has been supposed, an isolated member of the animal series, but has a number of characters which are not only common to it and other polyps of the Hydromedusse, but also to the Anthozoa, and probably to all the Cnidaria. It may be shown to possess ganglionic cells and muscular cells with a refractive fibril ; the structure of its nematocysts is analogous to that of other polyps ; the cnidoblast is in relation with the nervous elements as in Lucernaria and the Actiniae ; and the peristomial region can be shown morphologically, as well as physiologically, to be the seat of the central nervous system. The author is, as may be supposed, led to reject the neuromuscular theory of Kleinenberg, though he cannot admit all the arguments which Korotneff advances against it. Formation of Blastostyle Buds in Epenthesis McCradyi.f — Mr. C. P. Sigerfors has investigated the mode of reproduction in this Medusa to which Dr. W. K. Brooks was the first to call attention. He finds that the reproductive organs may develope in one of two ways. They may form the normal organs with male or female cells, or they may give rise to blastostyles. In the latter case the young reproductive organ gets its ectoderm much thicker and many-layered, owing to the multipli- cation of its cells. Meantime the cells of the endoderm enlarge and become vacuolated, though still remaining a single layer. Before the organ becomes mature the outer layer of ectoderm cells is separated off from the rest by the appearance of a supporting lamella beneath it. When maturity is near, the endoderm pushes out evaginations into the * Bergens Mus. Aarsberet. for 1891 (1892) 24 pp. (1 pi). t Arch, de Biol., xii. (1892) pp. 647-82 (2 pis.). x John Hopkins Univ. Cire , xii. (1893) p. 106. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 489 intermediate ectodermal layer, and these increase in size till they come to lie next the supporting lamella. The cells of the endodermal evagi- nations undergo marked changes, lose their connection with the rest of the endoderm, and lie in the middle mass in the form of closed cylindri- cal tubes. The outer ectoderm layer now sends inpushings between the tubes, and eventually grows completely around them. The rudiment of the bud thus formed consists of an endodermal tube which lies in the middle mass of cells, surrounded by a supporting lamella and overlaid by ectoderm. The buds, which are formed from both ectoderm and endoderm, are found as evaginations, in the usual mode of budding in Ccelentera. After the bud begins to form the reproductive organ generally enlarges to several times its usual size ; the radial canals enlarge, and quantities of food may pass into the cavity of the reproductive organ for digestion. Polydonia frondosa.* — Mr. E. P. Bigelow has made some observa- vations on this Medusa, the most interesting of which refer to its sexual dimorphism, the female presenting a special adaptation for the protec- tion of the eggs. In immature forms of both sexes aud in males, the appendages of the oral disc have the same structural arrangement as those of the oral arms. In the adult female the oral funnels disappear from the disc, while the oral vesicles increase in number till they com- pletely cover it. The eggs are discharged from the ovaries into the stomach, where cleavage commences ; they then pass out on to the oral disc, where they are cemented in small reticulated clusters at the bases of the vesicles; and they remain there till they become free ciliated planulse. The vesicles on the arms have the function of capturing food. If a vesicle be rubbed gently with a glass rod, there is an immediate con- traction of the muscles on the side stimulated, so that the vesicle, which usually stands upright, is suddenly bent down, and closes the mouth of the nearest funnel. A copopod | striking one of these vesicles is im- mediately stung by the nettle-cells, and, before it can escape from them, it finds itself within an oral funnel, tightly shut in by the overlying vesicle. The slime that surrounds the disc may serve also to entrap micro- scopic food, but, from the experiments which the author has made, he concludes that the usual food of these jelly-fish is not, as is often supposed, microscopic material, but copopods captured in the way described. Development of Stinging Organs in Hydroids.J — Herr L. Murbach, in a preliminary notice, states that he finds that the fission of the so- called interstitial cells, which leads to the formation of the stinging cells, is always amitotic. In the cell that forms the stinging capsule part of the nuclear mass is localized at the periphery of the nucleus to form a highly refractive, often curved, rodlet which is especially remarkable for its power of taking stains. The presence of a rodlet of this kind is characteristic of the developing stinging cell. The rodlet soon migrates from the nucleus into the cell-body, where it forms around * John Hopkins Univ. Circ., xii. (1893) p. 106. f So spelt, apparently correctly, by Mr. Higelow. % Zool. Anzeig., xii. (1893) pp. 174 and 5. 490 SUMMARY OF CURRENT RESEARCHES RELATING TO itself an area of non-staining substance. The rodlet gradually grows, and as it does so takes on one of the varied forms characteristic of the cell. At the proximal end of the young capsule the tube is now formed in very regular spiral turns around the nucleus of the cell. When fully formed, or sometimes even earlier, the tube passes into the capsule ; the cnidocil, which has the form of a pointed process of the muscular investment of the capsules, appears before the formative cell reaches the surface of the body. The author points out that the muscular stalks of the small stinging capsules of PJiysalia utriculus are not, as has been hitherto supposed, transversely striated, but have the appearance of fine filaments set in a close spiral. The fibres on the short stalks of the large capsules appear to be of a similar character. Development of the Scyphostoma.* — Prof. C. Claus discusses the development of the Scyphostoma of Cotylorhiza, Aurelia , and Chrysaora, aud the general question of the systematic relations of the Scyphome- dusse. He first describes the monodisc strobilation of Cotylorhiza, and points out that the middle stratum in Coelentera has not always the same morphological value. Is the proboscis of the Scyphostoma clothed with endodermic epithelium or is it an ectodermic gullet ? To this old question Prof. Claus returns with vigour, and many arguments against the naturalness of the group Scyphozoa are marshalled. At the margin of the widely open mouth lies the boundary between the two cell-layers. The inner lining of the proboscis (in which a quadrangular basal tube with four interradial tseniolae-pads and a flatly expanded or collar-like proboscis region are distinguished) is endodermic. The processes of strobilation in Aurelia and Chrysaora , the formation of the mouth in the Ephyra, the so-called septal-funnels of the Ephyrse, and the relationships of the Scyphomedusa? are discussed with the author’s wonted force. There is much hard-hitting in the course of the argu- ment— sometimes indeed the continuity seems interrupted — and a precise summary is not easy. But the general conclusion is one for which those who know the author’s works are prepared, that the Cnidaria are divided into Anthozoa and Polypomedusae, and the latter into Hydromedusse and Scyphomedusse. A new Stauromedusa.j — Dr. Gr. Antipa describes Copria Sturdzei g. et sp. n., a Stauromedusa found near Capri. It has eight adradial marginal lobes modified into true arms, without secondary tentacles, but with a fringe round the arms divided into (16-20) small serrations. There are (5-8) peculiarly large batteries of stinging-cells on the sub- umbrellar wall. There are not even principal tentacles. The circular muscles of the umbrellar margin are annular, and are not divisible into eight isolated marginal muscles. Longitudinal muscles are distributed in a uniform funnel- like manner over the whole surface of the sub- umbrella. The four septal ridges of the radial pockets extend almost as far as the margin of the umbrella, where they are penetrated by an annular canal. There is a long oral stalk. There are eight adradial * Arbeit. Zool. Inst. Univ. Wien (Claus), x. (1892) pp 1-70 (3 pis.). f MT. Zool. Stat. Neapel, x. (1893) pp. 618-32 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 491 gonads. An umbrella-stalk serves for attachment. The genus does not seem referable either to the Tesseridse or to the Lucernariidae ; and for its reception the author proposes a new family Capriidse. Classification of Anthomedusae.* * * § — Dr. C. Hartlaub has some criti- cisms on E. Vanhoffen’s division of the Anthomedusae into two families (Codonidae and Oceanidae) according to the form of the gonads. Thus, the genus Cladonema cannot be ranked, as Vanhoffen places it, with the Oceanidae. It should have been ranked with the Codonidae. Van- hoffen’s union of the genera Pandaea and Tiara is not justifiable. The author has some notes on the genus Turris, and describes a new species T. caeca , which closely resembles T. digitalis Forbes. A new Hydroid.f — Dr. E. Zoja describes a new genus of Hydroids under the name of Umbrellaria , with the single species U. Aloysii. The trophosome, which alone is known, has a rudimentary hydrocaul, en- sheathed in a rudimentary perisarc. The hydranths have a single wreath of (10-15) filiform tentacles and a conical hypostome. There is a filiform, branched, prostrate hydrorhiza, and there are two forms of nematocysts. Porifera. Australian Calcarea Heteroccela.J — Dr. A. Dendy has prepared a synopsis of the Australian members of this group of Calcareous Sponges, in which he proposes a classification, and describes some new genera and species. The author’s first family is that of the Leucascidse, established for a new genus Leucascus ; in it the long and narrow flagellated cham- bers are copiously branched ; they communicate at their proximal ends with exhalant canals which converge towards the oscula, and their blind distal ends are covered by a perforated dermal membrane. Their skeleton consists principally of small radiates irregularly scattered. Two species of the new genus have been found near Port Phillip Heads, and one of them has also been found at Port Jackson. The second family contains Sycetta , Sycon, and Sycantha, and is called that of tho Sycettidas. The third family, Granti[i]dae, contains Grantia (with a new sub-genus Grantiopsis ), Ute, Utella g. n., Anamixilla, Sycyssa, Leucandra , Lelapia , and Leucyssa. The fourth family is that of the Heteropidae, the first genus in which, Grantessa of von Lendenfeld, has, like some others, its characters emended ; the other genera are dieter opia and Vosmaeropsis g. n. The last family Amphoriscidae contains three of Haeckel’s genera — Amphoriscus , Syculmis , and Leucilla , with Polejaeff’s genus Heteropegma ; the characters of all these four are emended. Seventy-eight species are catalogued, sixteen of which are new. Sponges of the ‘ Hirondelle.’§— M. E. Topsent devotes his present memoir to the Sponges of the North Atlantic. Of the 167 species col- lected in the three campaigns of the yacht, 58 are new to science, and some of them offer characters which are of value for classification, and others present new forms of spicules. Esperiopsis polymorpha is cited as an admirable example of polymorphism. * Nachr. K. Gesell. Wiss. Gotting., 1892, pp. 17-22 (3 figs.), t MT. Zool. Stat. Neapel, x. (1893) pp. 519-26 (1 pi.), j Proc. Roy. Soc. Victoria, 1892, pp. 69-116 (from separate copy). § Resultats Scientifiques, &c., ii. (1892) 165 pp., 11 pis. 1893. 2 M 492 SUMMARY OF CURRENT RESEARCHES RELATING TO Gemmules of Spongillidae.* — Dr. W. Weltner, after some account of the structure and history of the gemmules of fresh-water Sponges, points out that our knowledge of their developmental history is still incomplete ; there are two primary questions which still need to be answered — the origin and nature of the cells which form the foundations of the gemmule, and the fate of these cells. It is possible that the gemmule is formed from a single cell which has the value of an ovum, in which case the gemmule would have to be regarded as a mass of segmenting cells. But the internal mass of the gemmule may arise from several equal cells of the mesoderm, or from several unequal cells, or, finally, the gemmule may be formed by cells of two or three germinal layers, in which case the gemmule would be a bud. Protozoa. Stigmata of Mastigophora.f — Herr E. Franze has made a study of the stigmata or eye-spots of Flagellate Infusoria. He finds them to be the simplest optic organs, and to consist of a plasmatic finely marked ground substance ; in this there are deposited numerous oily red granules, and one or a few or many highly refractive granules ; these latter, in the Euglenoidea, consist of paramylum, and in other Masti- gophora of amylum ; the granules are generally regularly arranged, but are sometimes irregular, and they exhibit a differentiation into larger, central, or excentric crystalline bodies, and smaller, always more numerous, lens-bodies. The larger granules are generally imbedded in the pigment, while the smaller bodies lie on it. Besides these stigmata there are others which consist of one layer of grains of amylum, and a layer of pigment which completely surrounds it. Stigmata of this kind are, as a rule, found in Chlamydomonads, Volvocinea, Dinobryinea, and a few others. The stigmata serve as organs for the perception of light ; the crystal- line body concentrates the light, the lens-bodies serve to concentrate the perception of light, and the pigment-layer is not only light- absorbing, but also light-perceiving. They are also capable of perceiv- ing heat, and the influence of light produces thermotactic movements, which are either thermophilous or thermophobic. The eyes of Turbellarians and Eotifers are not homologues of the stigmata ; the external resemblance between the two kinds of differentia- tions are due to similarity of function. The so-called oral-ridge ( Mundleiste ) of various Monads is probably composed of highly re- fractive granules ; what their true function is is still uncertain, but it is certain that they are not specific light-perceiving organs. Merotomy of Ciliated Infusoria.^ — Prof. E. G. Balbiani finds that in the Ciliated Infusoria, which may be considered as one of the most favourable types for the physiological study of cells, certain functions are fulfilled by the protoplasm alone, and others by it and the nucleus. The former are the different modes of movement, and the power of directing the body during progression. The latter are the various * Biol. Centralbl., xiii. (1893) pp. 119-26. f Zeitschr. f wiss. Zool., lvi. (1893) pp. 138-64 (1 pi.). % Ann. de Micrograpliie, v. (1893) pp. 1-25, 49-84, 113-37 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 493 cellular secretions — secretion of the cuticle, of the acid fluid in the food- vacuoles, and, perhaps, other digestive fluids; the regeneration or reconstitution of organs and of the general form of the body, and the ultimate stages of division. There is no antagonism between the proto- plasm and the nucleus, but rather there are reciprocal relations whence results a harmonious action, which maintains their vitality and assures the integrity of their functions. Stentor polymorphis and St. igneus were found to be, with regard to merotomy, exactly like St. cseruleus ; * that is to say, fragments which contained a nucleus were alone capable of regeneration, while fragments which had no nucleus were destroyed after a few days. In JDileptus anser , where the nuclear substance is dispersed in the form of small granulations in all parts of the plasma, all the fragments have some power of regeneration, and it is very rapid. This rapid regeneration contracts with the slowness of Loxodes rostrum , a species with multiple nuclei, the fragments of which require no less than four or five days for the reconstitution of complete individuals. In the course of the regenera- tion of the fragments of Loxodes , a small secondary merozoite is some- times formed spontaneously at the expense of a portion of the principal merozoite which contains one or several nuclei ; this portion becomes free after being more or less completely organized into a small Loxodes. Paramsecium aurelia forms a remarkable exception to the general property possessed by Protozoa of regenerating the parts which they have lost under the influence of the nucleus. Mutilated individuals may live for a month or more without presenting any signs of regeneration. The contractile vacuoles are the only parts which are regenerated, but this is not an organic new formation. It is only when the loss of substance is slight, as when a small part of one of the extremities of the body is cut, that it is able to effect repair. Fragments which contain no nuclear portion disappear in the cultivations much more rapidly than non-regenerated nucleated fragments. Experiments with colouring matters show that it is probable that the nucleus has an influence on the secretion of acid in the vacuoles, and probably also on that of the other digestive juices. It sometimes happens that in multiplication by division the products do not become free, but remain united and form a kind of colony. During such a multiplication the nuclei may remain connected together, and form a large mammillated mass. There is in this case a suppression of the later stages of division, due probably to a lesion of the nucleus of the merotomized individual ; it is never seen except in Paramsecia which have suffered a mutilation of their anterior portion. Sometimes lesion is followed by a prolongation of substance in the region of the wound. Reproduction of Orbitolites.j' — Mr. J. J. Lister, from the examina- tion of spirit material, has been able to find that large brood-chambers are formed at the margin of the disc during the later stages of growth. These are at first lined with a thin layer of protoplasm. At a later stage the central region of the disc is found to be empty, and the whole of the protoplasm is massed in the brood-chambers in the form of spores. * See this Journal, 1892, p. 803. f Proc. Cambridge Philosoph. Soc., viii. (1893) pp. 11 and 12. 2 m 2 494 SUMMARY OF CURRENT RESEARCHES RELATING TO These spores have the structure of the “primitive disc” which, during the early stages of growth of Orbitolites occupies the centre of the shells. When they are liberated each becomes the centre of a new disc. In Orbitolites , therefore, there is reproduction by spore formation. Depositions within Foraminifera.* — Dr. L. Rhumbler has studied these bodies, some of which Max Schultze, Carter, and others regarded as reproductive. (1) Within Truncatulina lobatula and others there is often a diatom allied to Cocconeis. (2) In Saccammina spliserica , Truncatulina lobatula , Hyperammina friabilis there are peculiar cor- puscles with a hyaline membrane. They may be faecal or possibly the results of decomposition. (3) A third kind of body is common in Foraminifera from muddy bottoms or from among rotting detritus, and also occurs in fallen-off spines of Ecbinocardium , &c. They are deposi- tions of silicate of iron and are the result of decomposition. Nuclear Division and Spore-formation in Rhizopods.f — Prof. A. Gruber has been able to detect karyokinetic division in Arcella. The stage observed was that showing two daughter asters. Noteworthy was the very large number of spindle-fibres. The number of chromatin loops was also great. Gruber has observed Arcellse with nineteen, and even thirty-two nuclei, thus confirming the occurrence of spore-formation. He also observed a specimen of Lecytliium hyalinum with eight nuclei. As a caution he notes how he discovered numerous small amoeboid organisms within Arcella ; they suggested spores ; but they were only parasites, for the two nuclei of the host were in some cases quite distinct. Dimorphism in Development of Hsematosporidia.j; — M. A. Labbe finds that Drepanidium ranarum and D. Danilevslcii have two modes of reproduction, as is shown by the essential differences in the spores, which may be called macrospores and microspores. Cytocysts with macrospores are of very variable size, and often develope in the leuco- cytes ; they are the only ones yet known, and agree with those already described by Pfeiffer. The cytocysts with microspores are found in the liver and spleen ; there may be here as many as fifty or sixty very small sporozoites, 3 to 5 /x long, elongated like bacteria, but provided with a nuclear spot. The cytocysts with macrospores are found both in spring and autumn, but it is only at the beginning of the summer that those with microspores are met with. * Nachr. K. Gesell. Wiss. Gotting., 1892, pp. 419-28. t Ber. Nat. Gesell. Freiburg i. B., vi. (1892) pp. 114-8 (1 pi.). X Comptes Bendus, cxvi. (1893) pp. 1209 and 10. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 495 BOTANY. A. GENERAL, including- the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-structure and Protoplasm. Streaming of Protoplasm and Transport of Nutritive Substances.* Commenting on the observations of Hauptfleisch on this subject,'!' Herr F. Kienitz-Gerloff brings forward additional arguments in favour of his previous view — as opposed to that of Pfeffer — that the streaming of protoplasm is a general phenomenon in all living cells, and that the protoplasmic connections from cell to cell assist in the transport of food- materials. External irritation may produce a double effect on the streaming of protoplasm, first retarding and then accelerating it. Reduction of the Chromosomes in Nuclei. J — Mr. E. Overton refers to the researches of Guignard, Strasburger, and others, which show that a reduction in the number of chromosomes or chromatin-segments takes place in connection with the development of the reproductive cells of Angiosperms. He has followed out a similar line of investigation in Gymnosperms ( Ceratozamia , Tsuga, Larix , Ephedra ), and finds that a similar reduction takes place in the mother-cells of the pollen, and persists through the whole male gametophyte. In the endosperm this reduction occurs in the earliest stages of its development, whereas the nuclei of the cells of the nucellus and of the integument have the full number of chromosomes. The reduction is, therefore, probably effected duriug the formation of the embryo-sac, and persists throughout the whole female gametophyte or endosperm, includicg the oosphere. As far, therefore, as investigation has at present been carried, the sexual and the non-sexual generations in Gymnosperms differ in the nuclei of the latter containing twice as many chromosomes as do those of the former. In Pteridophyta and Muscinese it seems probable — although the investigation is attended with considerable difficulties — that the reduction takes, place in the spore-mother-cells, and also persists throughout the gametophyte. Pectic Substances in Tissues. § — Pursuing his researches on the properties and distribution of pectic substances in plants, M. L. Mangin has, by the process already described, || demonstrated their presence in plants belonging to all the chief divisions of the vegetable kingdom,— Phanerogams, Vascular Cryptogams, Muscinete, and Thallophytes, and in all the tissues the membrane of which is not hardened by lignin or suberin. The chief exceptions to the presence of these substances are furnished by some classes of Fungi — Peronosporete, Saprolegnieas, Peri- sporiaceae, Uredinese, and Ustilaginete — and by certain hairs, as those of cotton. The membrane of soft tissues — parenchyme, collenchyme, bast, * Bot. Ztg., li. (1893) lte Abtheil., pp. 36-42. f Cf. this Journal, ante , p. 344. t Ann. Bot., vii. (1893) pp. 139-43. § Journ. de Bot. (Morot), vi. (1892) pp. 363-8; vii. (1893) pp. 37-47, 121-31 (2 pis.). Cf. this Journal, 1892, p. 809. || Cf. this Journal, ante, p. 417. 496 SUMMARY OF CURRENT RESEARCHES RELATING TO and meristem— always contains pectic substances associated with cellulose; the most widely distributed forms being pectic acid and pectose. Pectic acid is usually found combined with inorganic bases, most commonly lime. The ill-defined substance known as pectose is asso- ciated with calcium pectate in all the soft tissues, sometimes replacing it, especially in young tissues. The calcium pectate is found exclusively in the middle layer which separates the cells, cementing them together, and constituting the “ intercellular substance ” of Mohl. The detection of these substances is described in detail in a number of species of Equisetum and in a variety of flowering plants. It is insoluble pectates, chiefly of lime, that constitute the sculpturings — frequently in the form of rods or knobs, which so often mark the cell- walls which bound intercellular spaces. The substance which clothes the walls of intercellular spaces is also of this nature, and not proto- plasmic, as has been asserted by some authors. In some cases a portion of these deposits is capable of swelling up in water and becoming partially gelatinized. (2) Other Cell-contents (including- Secretions). Pigments of the lower Cryptogams.*— Prof. W. Zopf has studied the nature of the pigments in various Algae, Fungi, Lichens, Myxomy- cetes, and Schizomycetes. The properties are given of the haematochrome obtained from Trente - poblia Iolithus ; the author determined it to belong to the class of carotins (lipochromes). A table is given of the spectra of the various carotins. The colouring matter of various yellow lichens was investigated. From Cetraria Pinastri and G. juniperina , especially from the medulla, was obtained a resinous acid (“ pinastric acid”); Sticta aurata does not contain this acid, but a crystallizable pigment insoluble in mineral acids and alkalies (“ stictaurin ”). The red colour of the medulla of Physcia endococcinea is due to the presence of two crystallizable pigments of an acid character, “ rhodophyscin ” and “ endococcin.” Callopisma vitellinum yields two pigments, calycin and a new lemon-yellow “callopismic acid.” Calycin was also obtained from Acolium tigillare. A new yellow acid, “ placodic acid,” was obtained from Placodium fulgens and Calycium chlorinum. The orange-red pigment of Pilobolus Kleinii , oedipus, and crystallinus , insoluble in water, but easily soluble in alcohol, chloroform, and carbon bisulphide, is a lipochrome similar to that of Chroolepus and of Bacterium egregium. This yellow pigment was found to be taken up also by two parasites of the Pilobolus , Pleotrachelus fulgens and Endobiella destruens. Carotin was found also in certain insects belonging to the Chryso- melidem and Coccinellese, Lina Populi and Tremulse , and Coccinella sep- tempunctata and quinquepunctata. The fructification of Bulgaria inquinans was found to contain six distinct pigments, a red crystallizable pigment (“ bulgarin ”), a blue pigment (“ bulgarcoerulein ”), a yellow resin (“ bulgaric acid ”), a yellow * Beitr. z. Phjs. u. Morph, niederer Organismen, Leipzig, 1892, Heft 1, pp. 30-56 ; and Heft 2 (1892) pp. 3-32 (2 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 497 amorphous pigment soluble in water, a red amorphous pigment soluble in water (“ bulgarerythrin ”), and a yellow fat. From Arcyria punicea (Mycetozoa) four pigments can be extracted by alcohol, viz. a yellow resinous acid, scarlet when solid, soluble in benzol (“ arcyric acid ”), a brownish-yellow resinous acid insoluble in benzol, a yellow fatty acid, and a yellow acid soluble in alcohol, in- soluble in ether and water. The scarlet colour of the organism appears to be due to the first of these. New Lichen-acid.* — Prof. W. Zopf has extracted from an alpine lichen Tliamnolia vermicularis , distinguished by its chalky or greyish white colour, a crystallizable acid which he regards as new, and to which he gives the name thamnolic acid. It occurs in the cortex of the lichen, and its properties are described in detail. Vegetable Ferments. j — Prof. J. R. Green gives a detailed account of what is known respecting the various kinds of ferment occurring in the vegetable kingdom. He classifies them under four groups, viz. : — (1) Carbohydrate enzymes, including the various kinds of diastase, inu- lase, invertase, the cytohydrolysts which attack cellulose, and the ferment which forms vegetable jelly from pectic substances; (2) Glu- coside enzymes, including emulsin or synaptase, myrosin, erythrozyme, and rhamnase ; (3) Proteo-hydrolytic enzymes, including vegetable pepsin, trypsin, and vegetable rennet ; (4) Glyceride enzymes, which decompose oils. Of diastase there appear to be two kinds, one concerned in transloca- tion, the other in secretion, of which the latter is the more active ; the former dissolves starch-grains without, the latter with corrosion. The action of diastase is always one of hydrolysis. Inulase is found where inulin replaces starch in various Composite. Invertase has the power of inverting cane-sugar, or of hydrolysing it into dextrose and levulose. Cytohydrolysts have been discovered in the germinating barley-grain and in certain fungi. Emulsion has been found in certain species of Amygdalus and Cerasus or Prunus, and is active in the formation of prussic acid ; myrosin is the characteristic enzyme of the Cruciferae ; rhamnase occurs in Bhamnus infectorius ; erythrozyme in madder-root. The ferments of Brosera, Dionsea , Pinguiculci, and other insectivorous plants are pepsins ; the best-known trypsins are the ferment of Carica Papaya, and that of the fig ; a rennet occurs in the latex, the bast, the leaves, the flowers, and the seeds of various plants. Glyceride enzymes have been found in various oily seeds. Besides the above-mentioned groups, the author describes the enzymes of fungi ( Fusarum , Botrytis, Torula Urese, &c.), and those of bacteria, and also states what is known respecting zymogens or enzyme- generators. The action of the enzymes is stated to be, in all cases except that of myrosin, one of hydration. It is in no way different from an ordinary chemical reaction. Some of them act only intracellularly, and do not, during their activity, leave the cells in which they are secreted ; while others are secreted in particular cells, and are excreted by them to work upon substances contained elsewhere. * Hedwigia, xxxii. (1893) pp. 66-9. t Ann. Bot., vii. (1893) pp. 83-137. 498 SUMMARY OF CURRENT RESEARCHES RELATING TO (3) Structure of Tissues. Function of the Protecting-sheath.* * * § — From experiments made with different species of snails, Herr A. Dreyer concludes that the tannin contained in the protecting sheath is an efficient protection against con- sumption by these animals. The odoriferous oil in the root-stock of the onion answers the same purpose ; and the same is the case with the alkaloids of Aconitum Napellus, Veratrum album , Colchicum autumnale, and Cicuta virosa. The function of the protecting-sheath is not, there- fore, a purely mechanical one ; it serves also a conducting purpose. It does not, however, appear to afford any protection against the attacks of parasitic fungi or bacteria. Sieve-tubes in the Xylem.j — Pursuing his researches on this subject, Prof. E. Chodat records the occurrence, in a large number of natural orders, of islands of sieve-tubes produced from a cambium which acts in a centrifugal direction, forming sometimes xylem, sometimes a soft tissue with sieve-tubes. In other orders an adventitious xylem is formed from a supernumerary generative layer produced at the expense of the peri- cycle. Structure of Phytolacca.ij: — Dr. 0. Krueh describes several details in the anatomical and histological structure of Phytolacca dioica. The chief structural specialities are the presence of vascular bundles in the pith, and the increase in thickness of the branches by the formation of supernumerary rings. On the principal axis each leaf has, as a rule, two buds in its axil, of which the one nearest the axis usually developes into a branch, while the other remains undeveloped. On the flowering branches, on the other hand, the axil of each leaf bears only a single bud. C4) Structure of Organs. Pollen-grains of Papaveraceae.§ — Dr. E. Baroni describes the pollen-grains of the following species of Papaveracese : — Papaver orientale , setigerum, and somniferum , Chelidonium majus, and Eschscholtzia crocea. The measurements are given of the dry grains, and the changes are described which are produced by immersion in water, solution of sugar, and glycerin. Development of the Integument of the Seed. — M. L. Guignard || describes the development of the integument of the mature seed in the Cruciferse and in some other orders, his conclusions differing in several points from those of Brandza.1I In the Cruciferee the observations were made on a large number of species belonging to all the more important tribes. In all cases he finds that the internal proteinaceous layer of the testa is derived from the outermost layer of the endosperm, the aleurone layer of authors, and * ‘ Beitr. z. Kermtniss d. Function d. Schutzscheide,’ St. Gallen, 1892, 57 pp. See Bot. Centralbl., liii. (1893) p. 383. t Arch. Sci. Phys. et Nat., xxviii. (1892) pp. 481-2. Cf. this Journal, 1892, p. 500. t Atti R. Accad. Lincei, ii. (1893) pp. 52-5. § Nnov. Giorn. Bot. Ital., xxv. (1893) pp. 130-5. || Journ. de Bot. (Morot), vii. (1893) pp. 1-14, 21-34, 57-66, 97-106, 141-53 (80 figs.); and Bull. Soc. Bot. France, xxxix. (1893) pp. 392-4; xl. (1893) pp. 56-9. «f Cf. this Journal, 1891, p. 491. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 499 not from the epiderm of the ovule. The whole of the endosperm, with the exception of this outermost layer, disappears during the maturing of the seed. The structure of the integument of the ovule at the period of impregnation differs considerably in the different genera and species of the order, and even sometimes in the same species. The external coat may consist of 2, 3, or 4 layers ; the internal coat is usually made up of 3 or 4, though in some cases the number is much greater, even up to 15. The modifications which take place in the course of ripening of the seed are also numerous, especially in the outer coat ; the outermost layer almost always becomes mucilaginous. The layers of the inner coat usually become more or less consolidated. The pro- teinaceous layer derived from the outermost layer of the endosperm is always persistent. The other orders examined were the Capparidese, Resedaceae, Balsami- neae, Hypericaceae, Linaceae, and Malvaceae. In all cases the ovule is provided with 2 integuments. In the first-named four orders the remains of the endosperm in the mature seed are reduced to a single layer, as in the Cruciferae; in the Linaceae and Malvaceae it is more completely retained. Prof. R. Chodat and Mile. A. Rodrigue* have studied the development of the integument of the seed in the Polygalaceae. In the section Orthopolygala of Polygala the ovule has two coats, each of which is composed of 2 layers of cells ; the testa of the ripe seed being derived from the primine only. A very small portion of the nucellus remains in the ripe seed as a band separating the integument from the endo- sperm. The aril is formed entirely at the expense of the primine. In Polygala Chamsebuxus the primine of the ovule is composed of three layers. Anatomical Characters of Persistent Leaves.! — M. G. Lalaune summarizes the characters, drawn from a great number of examples, in which persistent or evergreen differ from deciduous leaves. The epiderm is of normal structure during the first year, but towards the end of the period of vegetation the cuticle begins to thicken and the cell-cavities to decrease in size. In the second year this change continues, and there may even be a lignification of the cell-walls, as in Rhododendron ferrugineum. There is a tendency for the opening of the stomates to diminish, and for the walls of the guard-cells to thicken, while their cavities almost disappear. The hypodermal collenchyme is more strongly developed, and its walls become thicker and sometimes somewhat lignified. The number of vascular bundles varies within the same species, as is strikingly the case in the ivy ; the sclerome is usually strongly developed ; sclerenchyma- tous cells frequently occur in the fundamental parenchyme. The pali- sade-tissue consists of only a single layer in evergreen, of several layers in deciduous leaves. Influence of External Conditions on the Form of Leaves.t — Mr. P. Groom records the fact that in one and the same plant (an epiphytic * Arch. Sci. Phys. et Nat., xxix. (1893) pp. 319-21. f Actes Soc. Linn. Bordeaux, xliv. (7 pis.). See Bot. Centralbl., liv. (1893) p. 113. X Ann. Bot., vii. (1893) pp. 152-3. 500 SUMMARY OF CURRENT RESEARCHES RELATING TO orchid of Singapore) growing partly in the sun and partly in the shade, strong sunlight and drought combined have the effect of causing a distinct elongation of all the cells in the exposed leaves in a direction at right-angles to the surface ; the cuticle is better developed, and the leaf as a whole is thicker and smaller. Leaves of Iridese. — Mdme. Balicka-Iwanowska * has studied in detail the anatomical structure of the leaves of Iris and allied genera from a systematic point of view. She states that characters derived from this organ must be treated in connection with others dependent on the morphology of the flowers. In some cases, however, histological characters may be used in defining genera or groups of genera. Thus Patersonia is characterized by marginal emergencies and by a lignified pith ; Crocus and Bomulea by the section of their leaves ; Gladiolus by a completely lignified fibrovascular bundle in direct contact with the epiderm ; Iris and allied genera by their marginal hypodermal fibres. The genus Iris may be divided into three sections according as the leaves are tetragonal, equitant, or isolateral. The Ixieee and GladiolesB have isolateral leaves with a prominent mid-rib which is wanting in the IridinesB and Aristess. The Cipurinem and Tigridieae have folded leaves. Tritonia and allied genera have marginal epidermal fibres, and opposite or even coalescent bundles. With the exception of Iris , Morsea, Galaxia , and Crocus , all the Iridese have isolateral leaves. Dr. H. Ross f gives a detailed account of the comparative anatomy of the leaves of Iridese, derived from a study of 53 out of the 57 genera, and 300 out of the total number of about 700 known species. After a description of the general conformation of the leaves, special attention is directed to the epiderm and trichomes, the fibrovascular bundles, and the mesophyll. The specialities of the genera Iris , Hermodactylus, and Morsea are then referred to. Structure of Lathrsea.J — Herr E. Heinricher has paid special atten- tion to the structure of the underground organs and the mode of parasitism of Lathrsea squamaria and L. clandestina. The former was found parasitic only on Alnus incana. The haustoria occur, as a rule, not on the primary, but only on the lateral roots ; they are not placed, as has been described, exclusively at the extremity of the root-branches ; they are found along the whole length, and frequently give them a moniliform appearance. The author finds no confirmation of the state- ment of Kerner that the haustoria disappear completely in the autumn, and that the parasite connects itself again with its host in the spring by fresh haustoria. L. clandestina differs from L. squamaria chiefly in the abundant formation of roots on the rhizome. The succulent capsule of Lathrsea is forced open, when ripe, by the excessive development of the placenta. L. squamaria forms a large number of underground cleistogamous flowers which pass by insensible gradations into the ordinary open flowers. * Arch. Sci. Phys. et Nat., xxviii. (1892) pp. 413-35 ; xxix. (1893) pp. 185-200, 225-41 (3 pis. and 15 figs.). Cf. this Journal, 1892, p. 818. f Malpighia, vi. (1892) pp. 90-116, 179-205 (4 pis.). X Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 1-18. Cf. this Journal, ante , p. 63. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 501 Cotyledonary Glands of Rubiaceae.* * * § — Mr. T. Berwick records the occurrence of a pair of glands in the axis of the cotyledons in a large number of Rubiaceae before germination ; their position and form vary according to the species. The process of germination is described in the case of a large number of species belong to the order. Capitate Hairs with Vibratile Filaments. f — Prof. R. Chodat and M. R. Zollikofer record the occurrence of hairs of this description, not only in the fluid contained in the cups formed by the coalescence of the bases of the leaves in Dipsacus , but also completely exposed to the air on plants belonging to the orders Dipsacaceae, Scrophulariacese, and Solanacese. Their study is especially easy on the corolla of Antirrhinum majus. In the Solanaceae the vibrating filaments form dense cushions covering the greater part of the trichome. Velamen of Orchids.J — Mr. P. Groom calls attention to the fact that the velamen of the roots of orchids does not in all cases perform the same function. In some cases it is essentially an absorbent organ ; and it is then not confined to epiphytic orchids, but may be present, and even assume a higher development, when the root is subterranean ; while in other species it is mainly protective, preventing loss of water by transpiration, the absorptive function being carried on by the root- hairs on the ventral surface of the root. Roots of Ranunculaceae.§ — Mr. F. B. Maxwell describes the minute peculiarities in the roots of a number of American plants belonging to this order. His general conclusion is that, in the Ranunculaceae, it is impossible to distinguish the species, and in many cases even the genus, by the structure of the root. Environment influences the structure much more than specific relations. Plants of different species growing in similar conditions present much more resemblance in the structure of their roots than those of the same species grown in different conditions. The author classifies the species examined under three types as regards the changes effected by secondary growth, and under two as regards the structure of the meristem of the growing point. £. Physiology. Cl) Reproduction and Embryology. Structure of Hybrids. || — From the examination of a very large number of examples, Dr. J. M. Macfarlane arrives at the general result that hybrids hold, in their anatomical properties, an intermediate position between the two parents. This is displayed in the size, number, and position of the trichomes ; in the form and size of the nectaries ; in the structure of the cuticle and in the distribution of the stomates ; in other anatomical details such as the thickness of the cell- walls ; in the form and colour of the chromatophores and the form and size of the * Trans. Bot. Soc. Edinburgh, six. pp. 159-65. See Bot. Centralbl., liv. (1893) p. 176. f Arch. Sci. Phys. et Nat., xxviii. (1892) pp. 494-5. Cf. this Journal, 1892, p. 819. t Ann. Bot., vii. (1893) pp. 143-51. § Bot. Gazette, xviii. (1893) pp. 8-16, 41-7, 97-102 (3 pis.). (| Trans. R. Soc. Edinburgh, xxxvii. (1892) pp. 203-86 (8 pis.). 502 SUMMARY OF CURRENT RESEARCHES RELATING TO starch-grains ; in the quality of the odour of the flower ; in the time of flowering ; and in the capacity for resisting cold. A very striking illustration of this intermediate structure is afforded by the vascular bundle-sheath of the hybrid Philageria VeitcMi , which consists of eight or nine layers of cells ; while that of one of the parents, Lapageria rosea , consists of five, and that of the other parent, Philesia buxifolia , of eleven or twelve layers. The graft-hybrid Cytisus Adami does not present characters inter- mediate between those of the parents, but some characters of one, some of the other parent. The author distinguishes as “ unisexual heredity ” the property of transmitting a character possessed by one of the parents only. Thus, while Lajoageria rosea has nectaries on the sepals, and Philesia buxifolia has none, Philageria Veitchii has nectaries about half the size of those of Lapageria. In “ bisexual heredity ” properties belonging to each of the parents are transmitted. Thus Bibes Culverwellii has both the simple hairs of B. Grossularia and the oil-secreting hairs of B. nigrum. The author regards the nucleole as the essential carrier of hereditary properties ; from the nucleole radiate the chromatic filaments, and these pass into the cytoplasm, and probably form a reticulate connection between the separate cells. The plant may be regarded as a group of connected hermaphrodite cells, descended from a fertilized egg-cell, and bound together by a fine chromatic ramification, the centre of which in each cell is the nucleole. Cross and Self-pollination. — According to Miss Jane H. Newell* the stamens of the horse-chestnut, which are usually seven in number, open in succession ; the first flowers in an inflorescence are staminate, the later ones perfect and proterogynous. The change in colour of the nectar-guides, from yellow to bright crimson, appears to be for the purpose of indicating to the visiting insects that the flowers no longer contain nectar. The authoress believes, however, the flowers to be self- fertile. Dr. A. Magocsy-Dietz f states that (Enothera biennis is not only pollinated by night-flying insects, but is also self-pollinated. All the species of Forsythia grown in Hungary — F. suspensa , viridissima, and Fortunei , are heterostylous, but none of them produce seeds in that country, being but little visited by insects. M. Bruel * asserts that in F. suspensa and viridissima the structure favours self-pollination. Herr K. F. Jordan § describes the structure of the nectary in Fchium vidgare , and the mode in which its position aids in pollination by insects. According to Dr. Ida A. Keller, || pollination takes place within the unopened bud in Monarda fistulosa (Labiatae). Notwithstanding this, the flowers subsequently fully expand, and the stamens, and finally the style, are protruded. * Bot. Gazette, xviii. (1893) pp. 107-9. f Mathem. u. Naturwiss. Ber. aus Ungarn, ix. (1892) pp. 399-401 and 414. X Actes Soc. Linn. Bordeaux, xiv. p. 347 (1 pi.). See Bot Centralbl., liv. (1893) p. 114. S Ber. Deutsch. Bot. Gesell., x. (1893) pp 583-6 (5 figs.). ji Proc. Acad. Nat. Sci. Philadelphia, 1893, pp. 452-4 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 503 Dr. E. Cobelli * records his observations on the following flowers : — Melandrium rubrum, Philadelphus coronarius , Pulmonaria officinalis , and Primula officinalis, in all of which he finds arrangements for cross- pollination, and gives a list of the visiting insects observed. In the last instalment of his paper on Flowers and Insects, Mr. C. Eobertson j describes the structure of the flower and the mode of pollination, with the insect visitors, in a number of American plants, mostly belonging to the Orchideae, In all belonging to this order there appear to be adaptations for entomophily. Pollination of Naias and Ceratophyllum.J — M. E. Eoze has investi- gated the mode of pollination in Naias major and Ceratophyllum demersum, in both of which the whole plant, including the male and female flowers, is completely submerged. It is doubtful whether Naias major is monoecious or dioecious. The female flowers present a similar structure to those of Zannichellia j pains tr is. The ovary is surmounted by a very short style ending in three sepaloid expansions, which are not true stigmas. They form a kind of funnel into which the pollen-grains fall, and thus reach the stylar canal. In Ceratophyllum demersum the male flowers are seated on the same branch as the female flower, but below it. The ovary is surmounted by a long style entirely destitute of any stigmatic apex. In the upper part of the style is a canal, which appears to serve as a receiving organ for the pollen-grains, when they put out their pollen-tubes to reach the ovary. When the anthers are ripe they become detached from their filaments, and, buoyed up by the air-vessels which they contain, rise to the surface of the water, where they burst. At the same time the branches rise to near tjie surface, and bring the pistils into such a position, that the anthers floating on the surface can drop their pollen into the terminal canals of the styles. Fertilization, however, appears to take place but rarely. Secondary Effects of Pollination.§ — Mr. W. M. Munson gives a list of a number of plants in which the pollen appears to exercise an immediate influence on the mother-plant, and of others in which it does not. With several species of gourd and with Solanum Melongena seedless fruits were obtained when the access of pollen was prevented. The quantity of pollen has often a distinct effect on the form and size of the fruits, a large quantity promoting the full and symmetrical development of the fruit. Gynodicecism in the Iabiat3e.|| — Mr. J. C. Willis finds that, in the hermaphrodite plants of Origanum vulgare, there are frequently flowers in which one or more of the stamens are abortive ; and in the female plants there are occasionally flowers with one or more perfect stamens. Similar variations occur in the hermaphrodite flowers of other Labiatse. The author regards proterandry as the usual cause of gynodioecism. * Nuov. Giorn. Bot. Ital., xxv. (1893) pp. 5-15. t Bot. Gazette, xviii. (1893) pp. 47-53. Cf. this Journal, 1892, p. 820. X Bull. Soc. Bot. France, xxxix. (1893) pp. 361-4. § Ann. Rep. Maine State Coll., 1892, pt. 2, pp. 29-58 (1 pi.). See Bot. Centralbl., liv. (1893) p. 165. 11 Proc. Cambridge Phil. Soc., vii. (1892) pp. 349-52; viii. (1893) pp. 17-20. 504 SUMMARY OP CURRENT RESEARCHES RELATING TO (2) Nutrition and Growth (including- Germination, and Movements of Fluids). Effect of the Electric Light on Vegetation.* — As the result of a series of experiments Prof. E. Chodat states that the electric light promotes the germination of seeds, and the lengthening of leaves and stems ; the leaves, however, are not so well developed as those of plants not exposed to the electric light. Its effect, therefore, is analogous to that of prolonged darkness. On the movement of the leaves of Oxalis the electric light had no influence. Adaptations for Epiphytism.j — Herr E. Loew enumerates a number of plants, natives of northern Germany, which appear to be on the way to becoming epiphytic. He finds them to be specially characterized in two different ways : — In a large number there is a special adaptation for the dissemination of the seeds, either by the fruit being edible, and the seeds therefore passing into the excrements of birds or other animals, or by the fruit or seeds being furnished with a floating apparatus. In other cases the plant is especially adapted for the absorption of food- material from decaying vegetable substances by the possession of an abundant mycorhiza. Influence of the Seed on the Development of the Fruit.f — According to Herr A. Miiller-Thurgau, the reduction of the number of seeds in the grape from the normal number of four to three, two, or one, or their total suppression, is not due to the failure of pollination ; this causes the falling of the flower. It is the result of imperfect impregnation, the pollen-tubes either not reaching the oosphere, or not finding it in a condition for impregnation, the ovules having probably been imperfectly nourished. The growth of the berry stands in direct relation with the development of the seeds, the development of the flesh being dependent on the irritation caused either by the entrance of the pollen-tube or by the growth of the seed. When there is only one seed the flesh developes more strongly on the side on which the seed lies. The presence of seeds also lengthens the period of ripening. Similar results were obtained also with currants, apples, oranges, apricots, and peaches. (3) Irritability. Latent Irritability.§ — Prof. J. Sachs states that the well-known sensitive motions of the roots of epiphytes can be incited also in aerial roots by placing them in a condition where these movements can be brought into play. The irritability must therefore remain latent in all roots. He has proved experimentally that, while the primary root of a seedling possesses true positive geotropism by which it directs itself vertically downwards, the secondary roots have each a modified geo- tropism of their own, in consequence of which they assume a definite angle with the primary root. The tertiary roots again do not display geotropism of any kind, but spring from the secondary roots in all direc- tions. These facts were demonstrated by observations made on potatoes * Arch. Sci. Phys. et Nat., xxviii. (1893) pp. 478-81. Of. this Journal, ante, p. 66. t Abhandl. Bot.cVer. Prov. Brandenburg, 1892, pp. 63-71. X J B. Deutsch-schweiz. Versuchsstat., 1892. See Bot. Centralbl., liv. (1893) p. 26. § Flora, lxxvii. (1893) pp. 1-15. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 505 grown under conditions where the mode of growth of the roots could bo clearly followed out, showing the closest resemblance to that of the roots of epiphytes. Changes of Pressure in Mimosa.* — M. G. Bonnier has studied, by means of a manometer, the changes of pressure which take place in the motor cushion of the leaf of the sensitive plant when the leaflets are displaying their sensitive movements. He finds that, when the leaves are irritated, the pressure at the base of the lower surface of the motor cushion diminishes, and that it again increases as the leaves assume their normal position. If the leaves are maintained in this position by the action of chloroform, the pressure in the motor cushion remains unchanged. A decrease of pressure in the surrounding air causes a movement in the reverse direction to the sleep position, but does not communicate itself to the tissues of the plant. The variations in the movements of the leaflets are always connected with variations in the internal pressure of the motor cushion. (4) Chemical Changes (including Respiration and Fermentation). Physiology of Succulent Plants.f — M. E. Aubert has undertaken an exhaustive series of observations on various points connected with succulent plants. Those examined belonged chiefly to the Cactaceae, Mesembryanthemaceae, and Crassulacese ; but the degree of succulence in the various species of these orders varies greatly. With regard to their assimilation and respiration, he finds that the atmosphere contained within the tissues of these plants differs from the surrounding air in the proportion of the gases of which it is com- CO posed. The value of the fraction — -2 varies in direct proportion to the succulence of the species. The Crassulaceae and Mesembryanthemaceae with a thin cuticle manifest a greater exchange of gases with the sur- rounding atmosphere than most of the Cactaceae, while the succulent Euphorbiaceae are intermediate between the two. The two processes of assimilation and respiration proceed simultaneously in succulent plants, and the value of the fraction — is in direct proportion to their succulence. With regard to the organic acid contained in the sap, which has so great an influence on the turgor of the cells, M. Aubert finds that in the Crassulaceae it is malic (isomalic) acid, free or combined, with traces of tartaric ; in the Mesembryanthemaceae it is oxalic acid ; in the Cactaceae it is malic acid associated with a large quantity of gums. The amount of malic acid in the leaves of the Crassulaceae increases from the terminal bud to a point in the stem where the leaves have almost attained their maximum development; from this point it decreases in the adult leaves, but never completely disappears. The amount of malic acid also varies in different parts of the same leaf; it is least in those * Rev. Gen. de Bot. (Bonnier), iv. (1893) pp. 513-28 (2 pis.) ; and Bull. Soc. Bot. France, xxxix. (1893) pp. 365-8. f Ann. Sci. Nat., xvi. (1892) pp. 1-90 (9 figs.); and Rev. Gen. de Bot. (Bonnier), iv. (1892) pp. 203-19, 273-82, 320-31, 337-53, 373-21, 421-41, 497-502, 558-68 (1 pi. and 5 figs.). 506 SUMMARY OF CURRENT RESEARCHES RELATING TO parts which are most fully illuminated. In the Crassulacese he deter- mined that the formation of organic acids during the night is dependent on the assimilation of carbon previously effected in the day-time. The distribution of water in the different parts of plants belonging to the Crassulaceae corresponds to that of malic acid ; in Opuntia and the Cras- sulaceae it is the most parenchymatous region that contains the largest quantity of water. The presence of organic acids in the tissues is dis- tinctly unfavourable to transpiration. Influence of Light on Respiration.* — Herr W. Detmer gives the results of a series of experiments which appear to determine that light has no direct influence on the respiration of plants destitute of chlorophyll ; while in the green parts of plants both assimilation and respiration are retarded by the exclusion of light for a considerable period. No daily periodicity could be established in the intensity of the respiration. In germinating potato-tubers the respiration is decidedly more intense in the light than in the dark, light having apparently the power of disso- ciating the living molecules of protoplasmic albumen. Formation of Sulphates and Nitrates.f — Pursuing his investigations on the chemical changes which take place in plants during germination, M. E. Belzung finds that sulphates may be formed at the moment of germination by oxidation of the sulphur in the albuminoid reserve- materials ; while nitrates are never formed by the oxidation of the nitrogen of the albuminoid substances, but are always transported directly into the seedling from the nutrient material. A process of nitrification unconnected with bacteria is unknown in the vegetable kingdom. B. CRYPTOGAMIA. Algae. Parasitic Phaeosporese.f — M. C. Sauvageau enumerates the following parasitic species of Phaeosporeae : — Elachista stellulata on Dicfyota dicho- toma, not a facultative, but a true parasite ; E. Areschougii on Himanthalia lorea ; E. clandestina on Fucus ceranoides ; E. scutulata in the concep- tacles of Himanthalia lorea ; E. pulvinata in those of Cystosira ericoides and discors ; Ectocarpus investiens on Gracilaria compressa and multi- partita ; E. velutinus on Himanthalia lorea ; E. Valiantei on Cystosira ericoides; E. brevis sp. n., forming yellow-brown tufts on Ascophyllum nodosum ; E. minimus on H. lorea ; E. luteolus sp. n., forming a light- yellow down on Fucus serratus and vesiculosus ; E. parasiticus sp. n., forming small brownish spots on Cystoclonium purpurascens , Gracilaria confervoides , and Ceramium ruhrum ; E. solitarius sp. n., on Dictyota dichotoma ; Streblonemopsis irritans on Cystosira opuntioides ; Ectocarpus fasciculatus on Laminaria flexicaulis. Reproductive Organs of Prasiola.§ — Mr. T. H. Buffham describes structures in Prasiola stipitata which he regards as antherids and “ spores ” (fertilized oosperms). The former were seen to be discharging * Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 139-48, 149-53. f Journ. de Bot. (Morot), vii. (1893) pp. 87-91. Cf. this Journal, 1892, p. 825. % ‘ Sur quelques Algues Pheosporees parasites,’ 48 pp. and 35 tigs. ISee Bot. Centralbl., liv. (1893) p. 75. § Grevillea, xxi. (1893) pp. 90-2 (6 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 507 pollinoids. The male and female organs occur on different plants. He regards this discovery as a confirmation of the view that Prasiola is nearly related to Porphyra. Giffordia, a new Genus of Ectocarpacese.* — Mr. E. A. Batters separates Ectocarpus secundus from that genus as the type of a new genus Giffordia, in which the male cells and the sporanges in which they are produced differ in several important particulars from the female cells and their sporanges, while the true Ectocarpi are isogamous. The antherozoids of Giffordia are much smaller than the zoospheres, and are destitute of chromatophores. In the same genus must be placed E. fenestratus , E. Lebelii , and a new species G. Padinse described by Mr. T. H. Buff ham. f Chlamydomonas Kleinii sp. n.$— Herr W. Schmidle describes a new species of this genus found in ditches and pools in the Black Forest, which differs in several respects from the species hitherto described. It occurs in both a swarming and a palmelloid condition. In the former state each individual is an oval or cylindrical body, 32-28 p long and 12-8 p broad, with two very slender flagels. In the anterior portion is a linear reddish-brown “ stigma” or eye-spot, in which are always two well- developed pyrenoids, and there are two small contractile vacuoles which pulsate alternately. It has a striated appearance, owing to the arrange- ment of the chlorophyll-bodies in bands. The individuals swarm only for a short time, and then pass rapidly into the resting condition, and the cell-wall gelatinizes, the mucilage being distinctly laminated ; the flagels often remain for a considerable time, retaining a slow movement. The attachment of the individuals to one another in the palmelloid condition is but slight. In this condition both microspores and mega- spores are formed ; the first cell-division is always transverse, differing in this respect from that of all other species known. The usual number of megaspores and microspores derived from each cell is 4 and 32 or 64 respectively. No conjugation was actually observed; but there were indications of this taking place between an active microspore and one which had already come to rest. Rhodochytrium, a transitional form between the Protococcacese and the Chytridiace8e.§ — Prof. G. v. Lagerheim describes a parasitic alga found on a species of Spilanthes (Composite), which he makes the type of a new genus with the name Bhodochytrium SpilantJiidis. It appears on the stem and leaves of the host in the form of blood-red spots which are the sporanges of the parasite. They are always in contact with a vascular bundle, and produce only one kind of zoospore, which is biciliate and may germinate either with or without conjugation. When a zoospore settles on the epiderm of the host, it does not penetrate through a stomate, but puts out a germinating tube which makes its way between two epidermal cells. The rhizoids which are put out from the germinating tube form a complete weft round the vascular bundle. Nearly the whole organism is coloured by a red pigment; both the sporanges and the spores themselves contain abundance of starch ; but * Grovillea, xxi. (1893) pp. 85-6. f Tom. cit., pp. 88-9 (3 figs.). % Flora, lxxvii. (1893) pp. 16-26 (1 pi.). § Bot. Ztg., li. (1893) lte Ahtheil., pp. 43-52 (1 pi.), 1893. 2 n 508 SUMMARY OF CURRENT RESEARCHES RELATING TO the presence of chlorophyll is very doubtful. A second kind of organ of propagation, resting sporanges, was also observed. BJiodocJiytrium is most nearly allied to Phyllobium, but differs in the presence of two kinds of sporange, in the mode of germination, and in the absence of chlorophyll ; in the last two characters it presents an approach to the Chytridiaceae. Tetrasporidium, a new Genus of Algae. * * * § — In a collection of Algae from Java, Prof. M. Moebius finds a freshwater species which he makes the type of a new genus allied to Tetraspora , and names Tetrasporidium javanicum. The following is the diagnosis of the genus : — Thallus spongiosus, irregulariter perforatus, structuram et multiplicationem cellularum eandem quam Tetraspora praebet ; reproductio fit sporis (zoosporis aut gametis ?) in cellula incrassata divisione succedanea senis denis evolutis, periplasmate multo in sporangio remanente ; diam. cellul. veg. 6-7 /x, sporangiorum 20-25 /x. The following new species are also described : — Cladophora Jiuviatilis , G. Beneckei , C. clavata , C. elegans , Siphonocladus exiguus. Fungi. Germination of Parasitic Fungi. | — M. M. Biisgen has studied the mode in which the germinating filament penetrates into the tissue of the host-plant in the cases of Botrytis cinerea , Fusicladium pyrinum , and several species of Peronosporeae, Erysipheae, and Uredineae. There is always the closest contact between the germinating parasite and the host, either by the apex only of the former, as in the Peronosporeae, or along its whole length, as in the Uredineae. The hyphae of the parasite which are in contact with the host put out swellings or “ appressoria,” by means of which this intimate contact is maintained, as well as by haustoria, or branches of the hyphae which penetrate into the tissue of the host-plant. These haustoria or “ infection-filaments ” are not the result of contact-irritation. The appressoria have the double function of causing intimate contact between the parasite and the host, and of indicating the direction in which the infection-filaments shall be put out. In the Peronosporeae and Uredineae this intimate contact is assisted by spontaneous nutations ; the movement of the zoospores of Cystopus towards the stomates appears to be partly the result of chemotropism. Botrytis cinerea also displays chemotropism as well as contact-irritation. New Parasitic Fungi. — The late Dr. C. Tubeuf J found Alnus viridis attacked by Valsa oxystoma, infesting the wood, and causing the leaves to fall. This fungus had previously been known only as a sapro- phyte. Prof. R. Hartig § finds a hitherto undescribed parasitic fungus, pro- bably a Nectria, attacking the seedlings of a number of trees, especially conifers, destroying them in the same way as Phytoplithora omnivora. It produces sickle-shaped usually six-celled conids ; and rudiments of peritheces or pycnids were observed. * Ber. Deutsch. Bot. Geselb, xi. (1893) pp. 118-39 (2 pis.). t Bot. Ztg., li. (1893) lte Abtheil., pp. 53-72 (1 pi.). % Forst-naturw. Zeitschr., i. (1892) pp. 387-90 (1 pi.). See Bot. Centralbl., liii. (1893) p. 329. § Tom. cit., pp. 432-6 (4 figs.). See Bot. Centralbl., liii. (1893) p. 328. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 509 Tlio same author * * * § observed Septoglceum Hartigianum, hitherto unknown as a parasite, parasitic on the maple. The only mode of propagation observed was by light-brown conids. Herr Behrens f describes a disease of the tobacco-plant caused by the attacks of Alternaria tenuis, which occurs also in a conidial form, probably belonging to a Hormodendron. Herr 0. KirchnerJ describes young plants of Cytisus capitatus destroyed by an undescribed parasitic fungus belonging to the Hypho- mycetes, which he names Ceralophorum setosum. Sig. F. Cavara §' finds, on the fruit of Citrus vulgaris , a parasitic fungus which he makes the type of a new genus Trichoseptoria, with the following diagnosis : — Perithecia carpophila, innato erumpentia, macu- licola, trichomatibus undique fulta, membranacea ; basidia nulla ; sporulae bacillares, septatse, hyalinae. Chanci, a Disease of Mushrooms.|| — M. J. Costantin, who had previously described this disease, and pointed out the existence of the mycele, has now succeeded in obtaining, by means of pure cultivations, the fructification, and has thus been able to identify the parasite as a Clitocybe (a species closely allied to, if not identical with C. candicans). The appearance of dung affected by this disease is little different from that which contains the mushroom mycele. The two, however, may be distinguished by the smell. The odour from the mushroom is delicate and agreeable, but when Chanci is present it is strong, pene- trating, and disagreeable. Relationship of Calcicolons Lichens to their Substratum.^ — Sig. E. Baroni describes the structure of the thallus of the calcicolous lichens Aspicilia calcar ea, Lecidea fusco-atra , and Verrucaria rupestris, especially in relation to the formation of the gonidial zone and of the apotheces beneath the surface of the rock on which they grow. He considers it probable that the hyphse penetrate the rock through the agency of an acid which they secrete. Structure of Yeast-cells.** — Herr G. Hieronymus has undertaken a series of observations on a form of Saccharomyces , with the view of determining the question of the presence or absence of a nucleus in the cells. He finds the contents of the cells to present a similar fibrillar structure to that in the Phycochromacese. The angular granules (pro- bably nuclein) which lie in the protoplasm are always arranged in rows intertwined into a more or less regular spiral or ball, which the author calls the central thread. He regards the protoplasm as originally structureless, the definite structure being developed only as the result of the penetration of fluids into the cell from without. * Tom. cit., pp. 289-91 (1 pi.). See Bot. Centralbl., liii. (1893) p. 181. t Zeitschr. f. Pflanzenkrankheiten, ii. (1892) p. 327. X Tom. cit., pp. 324-7. § Atti R. 1st. Bot. Univ. Pavia, 8 pp. and 1 pi. See Bot. Centralbl., liv. (1893) p. 26. || Bull. Soc. My col. France, viii. (1892) pp. 153-60 (1 pi.). See Centralbl. f. Baktcriol. u. Parasitenk., xii. (1892) pp. 765-6. Cf. this Journal, ante, p. 74. Bull. Soc. Bot. I tal., 1893, pp. 136-40. ** Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 176-86 (1 pi.). Cf. this Journal, ante, p. 366. 2 n 2 510 SUMMARY OF CURRENT RESEARCHES RELATING TO Granules and Vacuoles of Yeast-cells.* — Herr J. Raum examined ten different kinds of yeasts for cell-nuclei. The yeasts used were in pure cultivations, and they were stained and fixed in different ways. He came to the conclusion that true nuclei were not present, although he found in all the species examined those peculiar bodies known as sporogenic granules. These, when stained with methylen and Bismarck- brown, become black or dark brown, and when treated with eosin or rose-Bengale and methylen-blue became dark violet. These granules are by no means invariably present, being found only when the con- ditions of nutrition are favourable, and are absent in badly nourished and senile forms. With regard to number, shape, and arrangement within the cell, the granules exhibit great variation, though these remain very much the same for each species. No membrane or any definite structure could be observed ; hence they are probably of fluid consistence. Though their chemical composition is not yet ascertained, their digesti- bility by means of pepsin suggests that they are of the nature of nuclein. The author also found that vacuoles are of frequent occurrence in yeast-cells, but are not always present ; e. g. they are absent altogether in kephir yeast, and their size is in inverse ratio to that of the granules. From observations on cells while budding the author finds that neither the vacuoles nor granules are connected with this process. Nor is there any direct connection between the granules, the vacuoles, and spore-formation. Animals, when infected with pure cultivations of yeast, suffered from fever and dyspnoea ; and it was noticed that yeast-cells from internal organs behaved differently towards stains to what they did when culti- vated in fluid nutrient media. Saccharomyces.f — Prof. E. C. Hansen defends the independence of the genus Saccharomyces against the attacks of H. Moeller, who advo- cates the extension of the term. The latter declines to believe that certain forms seen within yeast cells are true spores, inasmuch as they do not possess a spore-membrane, nor have they been observed to mature into germs ; and, as there is for him no morphological difference between Ustilago sporids and the yeasts examined by him, the genus Saccharomyces should be enlarged. According to the author, not only are these forms enclosed in a membrane, but every step in their after development can be observed under the Microscope. Hence, they are really endospores ; and he goes on to say that among the Blastomycetes or yeast-fungi there exists a group embracing numerous species, which differ from the rest of the Blastomycetes in the internal development of spores. This particular group has been introduced into the system under the generic appellation of Saccharomyces. He holds that it is better to adhere to the old name until the conjectural original form is discovered. Then will be time enough to extend the definition of genus Saccharomyces. Fermentation Differences of Wine Yeasts.| — The experiments of Herr J. Wortmann on wine yeasts from various wine districts were * Zeitschr. f. Hygiene, x. (1891) pp. 1-50. t Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 16-9. Cf. this Journal, ante , p. 220. X Landwirthschaftliche Jakrbiicher, xxi. (1892) pp. 901-36. See Bot. Centralbl., liii. (1893) pp. 318-9. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 511 principally intended to discover if there were any notable differences in their ferment action, and if so, whether any practical outcome were likely. Pure cultivations were made from ferments derived from various parts, and artificial must was inoculated with equal quantities at similar stages of development. The must was composed of extract of raisins to which had been added a definite quantity of tartaric acid and sugar. Erlenmayer’s flasks were used as cultivating vessels, and these were exposed to the same temperature conditions throughout. Every twelve hours the quantity of carbonic acid was estimated from the loss of weight, and at the end of fermentation the total quantity of alcohol and glycerin was determined. When the results were tabulated it was seen that the duration of fermentation varied according to the particular yeast from 17-32 days. The differences in the amount of carbonic acid formed were very slight, the maximum formation being attained in from two to three days. With regard to the quantity of alcohol produced by various yeasts, similar differences were observed, while those yeasts which had the shortest fermentation period produced the smallest amount of alcohol, and vice versa. Differences in the amount of glycerin formed conclusively indicate the specific differences of the yeasts used. Control experiments with natural must were made, the rest] of the experimental conditions being the same, and quite analogous results were obtained. The author concludes from his experiments that the number of races or kinds of Saccharomyces ellipsoideus is so great as not to be computable. Influence of Parasitic TJredineae on the Host-plant.* — Herr K. Fentzling describes the changes effected in a number of host-plants by parasites belonging to the genera Uromyces, Puccinia, Gymnosporangium, &c. The extent of the deformations are, in general, in proportion to the early period in life at which the host-plant is attacked. In external habit the effects are seen in the diminished height and branching, the smaller amount and size, but greater thickness of the leaves, the feebler development of wood, and the shorter life. In the leaves the epidermal cells are usually longer, intercellular spaces appear in the palisade- parenchyme, the spongy parenchyme increases in size, the cells becoming larger and more numerous, with intercellular spaces between them. In the stem the epidermal cells become longer, those of the cortical paren- chyme increase in number and size, there is a feebler development of wood, while the number of cells in the pith is larger. Hetercecious Uredinese. — Herr H. Klebahn j records the following observations on the life-history of various Uredinese. Gymnosporangium confusum occurs on Juniperus Sabina , and is gene- tically connected with an ascidio-form on Crataegus oxyacantha. Two species of Gymnosporangium are therefore parasitic on J. Sabina. Two new species of Peridermium are described, P. Stahlii and P. Plowrightii . From the former uredoforms were obtained on Alectoro- * ‘Morph, u. anatom. Unters. d. Veranderungen welcke bei einigen Pflanzen durch Rostpilze hervorgerufen werden,’ Freiburg-i.-B., 1892, 52 pp. See Bot. Centralbl., 1893, Beih., p. 83. Cf. this Journal, ante, p. 361. t Zeitscbr. f. Pflauzcnkrankkeiten, ii. (1892) pp. 91-5, 258-75, 332-43. 512 SUMMARY OF CURRENT RESEARCHES RELATING TO lophus and on Melampyrum pratense , and it appears to be connected genetically with Coleosporium Euplirasise. The latter is connected in the same way with Coleosporium Tussilaginis. It has been long known that, while the aBcidiospores of Peridermium Strobi and Cronartium ribicola germinate freely on almost all species of Bibes, B. Grossularia is exempt from their attacks. The author states that this immunity ceases if the gooseberry is grafted on Bibes aureum. The secidium of Euphorbia Esula belongs, like that of E. Cyparissias, to a uredo- and teleuto-spore form parasitic on Pisum sativum. Puccinia sylvatica , connected with JEcidium Taraxaci, was found on Car ex arenaria. P. Phragmitis is connected with an ascidium on Bumex crispus , and P. Magnusiana with one on Banunculus repens. Puccinia coronata , on Lolium perenne, is connected, not with 2Ecidium Grossularise , but with 2E. Bliamni. Under the name P. coronata two species appear to be confounded, both growing on various species of grass. The aecidiospores of JEcidium Convallarise give rise, on Phalaris arundinacea} to the uredo- and teleuto-spore forms of Puccinia Digraphidis. Herr P. Magnus * * * § gives further particulars respecting the occurrence and parasitism of the four European species of Gymnosporangium , viz. G . fuscum, juniperinum , clav arise for me , and confusum. In another communication f Herr Magnus contributes additional information on the species of Uromyces and JEcidium found on Euphor- bia, on the genetic relationship between the various species of Cseoma and Melampsora, and on Peronospora Cytisi. Development of the Spermogone of Cseoma.f — Mr. H. M. Richards describes in detail the structure and development of the spermogone of Cseoma nitens on Bubus villosus. It originates, in the first place, as an outgrowth between and not within the epidermal cells of the host-plant, but soon breaks through and absorbs the confining walls, and makes its way into the cavities of the surrounding cells. It is more superficial than the spermogone of most other Uredine®. Anthracnoses of the Solanacese.§ — Prof. B. D. Halsted states that on each of the three cultivated species of Solanacese, the tomato, the pepper ( Capsicum ), and the egg-plant, there is found a species of Gloeo- sporium and a species of Coleotrichum , to which different specific names have been given. By culture experiments he has determined that the three species of Gloeosporium have no structural differences, and that they are all identical with the bitter-rot of the apple Gloeosporium fructi - genum. It is also probable that all the three species of Coleotrichum are forms of C. Lindemuthi. Monilia fructigena.|| — Prof. J. E. Humphrey has investigated the life-history of this fungus, which causes mummifying of the fruits of Drupacese and Pomese, and states that the chains of so-called spores are not true conids, but chlamydospores or oi'diospores of the most primitive type. There are, however, true conids produced on sporophores. It is * Verkandl. Bot. Ver. Prov. Brandenburg, 1893, pp. xiv.-xvi. + Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 43-53 and 212 (1 pi.). X Proe. Amer. Acad. Arts and Sciences, 1893, pp. 31-6 (1 pi.). § Bull. Torrey Bot. Club, xx. (1893) pp. 109-12. jl Bot. Gazette, xviii. (1893) pp. 85-93 (1 pi). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 513 probable that the fungus is the persistent chlamydosporic and micro- conidial stages of a Sclerotinia allied to S. Vaccinii , the perfect stage of which has been partially or entirely suppressed. Phyllogaster, a new Genus of Phalloideae. — Under the name Phyllogaster saccatus , Mr. A. P. Morgan * * * § describes the type of a now genus of Phalloideae, with the following diagnosis : — Mycele fibrous, much branched ; peridium obovoid, consisting of two concrete layers, an inner and an outer one, rupturing irregularly; glebe composed of numerous roundish irregular masses or lobes of a green colour, attached to the inner surface of the upper part of the peridium ; spores minute, oblong, hyaline. The genus constitutes a bond of connection between the Phalloideae and the Lycoperdaceae. Mr. It. Thaxter f gives a detailed description of the same species ; and, from the absence of any volva or receptacle differentiated as such in the mature condition, suggests the establishment of a third subdivision of the Phalloideae, to be termed Phyllogastrejs. He proposes some modifica- tions in the generic diagnosis, especially from the fact that the peridium consists only of a single layer covered by an evanescent cortex, and coarsely reticulated through the presence of numerous irregular thin areas, which become perforate at maturity. Its nearest affinities are with the Clathreae. Luminosity of* Pleurotus olearius.J — A fresh series of observations by Prof. G. Arcangeli confirms him in his previous statement that the phosphorescence of this fungus, though most strongly displayed in the laminae, is not confined to the receptacle. It is accompanied by an elevation of temperature amounting to from 0* 7-1*1°, and is the result of respiration. Its function is probably to assist in the dissemination of the spores by attracting nocturnal animals. Myxomycetes. Labyrinthule8e.§— Prof. W. Zopf has studied the structure of this little-known group of Mycetozoa, and adds one species, Labyrinthula Cienkowskii , to the two previously described by Cienkowski. The species described carries on a partly saprophytic, partly parasitic existence on freshwater Vaucherise. The vegetative structure is com- posed of amoebiform bodies coalescing with one another by means of pseudopodes, which are continually extruded and retracted. These pseudopodes pierce the wall of the alga-filament, and the amoebiform structures form a network within it. They consist of granular colour- less protoplasm, and contain a nucleus and a vacuole. The formation of the fructification is preceded by a contraction of the pseudopodes, and occurs both outside the alga and in its vegetative and fertile branches. The amoebiform structures become quiescent, round themselves off, invest themselves with a membrane, and pass into the spore-condition. The germination of the spores was not observed. * Journ. Cincinnati Soc. Nat. Hist., xv. (1893) pp. 171-2 (1 pi.), t Bot. Gazette, xviii. (1893) pp 117-21 (1 pi.). X Atti It. Accad. Lincei, vi. (1890) pp. 197-214. Cf. this Journal, 1889, p. § Beitr. z. Phys. u. Morph, uiederer Organismen (Zopf), Pleft 2, pp. c (2 pis.) 1892. ' ,lk 426. 36-48 514 SUMMARY OF CURRENT RESEARCHES RELATING TO With regard to the systematic position of the Labyrinthulese, Zopf divides the highest order of the Mycetozoa, the SorophoresB, into two sub-orders, the Acrasiese and the LabyrinthuleaB. The former are characterized by having pseudoplasmodes, and by the sori being capitate, naked, and either stalked or sessile ; they live on dead parts of plants, dung, fungi, &c., and are divided into two families, the Guttulinese and the Dictyostelieae. The Labyrinthuleae have filiform plasmodes ; the sori are naked or imbedded in solid hyaloplasm, and sessile. They are partly saprophytic, inhabiting dung or salt or fresh water, partly parasitic, and comprise only the two genera Ldbyrintliula and Diplophrys. Protophyta. a. Schizophyceae. Lyngbyese.* — M. M. Gomont now gives a monograph of the second tribe of the Oscillatoriacese, the Lyngbyeae, distinguished by the sheath, when present, enclosing only a single trichome. They are divided into two sections, according as the trichome is septated or not. The first sec- tion is again divided into two sub-tribes, — Lyngbyoideas in which the filament is simple or pseudo-ramose, the sheath firm, sometimes dusky yellow, the trichome always straight at the apex [Plectonema 8 species, Symploca 11 species, and Lyngbya 21 species, including Leibleinia) ; and Oscillarioideae, in which the filament is simple, the sheath thin, always hyaline, mucous, more or less diffluent, apparently wanting in some species, the trichome often curved at the apex (Phormidium 29 species, Trichodesmium 3 species, Borzia 1 species, Oscillatoria 38 species, and Arthrospira 3 species). The second section consists of the sub- tribe Spirulinoideae, characterized by the trichome being twisted into a regular spiral, and of the single genus Spirulina 9 species. The follow- ing new species are described : — Plectonema purpureum , Symploca atlantica , S. Isete-viridis , Lyngbya Bivulariarum , Phormidium Crouani , P. Setchellianum , Oscillatoria Aghardiii 0. simplicissima , 0. acuminata , 0. numidica , Spirulina Nordstedtii. New Genera of Schizophycese.f — Among a number of Freshwater Algse obtained from Algeria, M. C. Sauvageau describes several new species, and the following new genera of Schizophyceae : — Synechocystis , nearly allied to Synechococcus , but with perfectly globular cells ; Tapi - nothrix, with the following diagnosis, — Filaments without heterocysts, very slender, simple, attenuated from a slightly thickened base, not pro- duced at the apex into an articulated hair ; sheath slender, very narrow, continuous, usually open above from the escape of hormogones; near Schizothrix and Amphithrix. Biology of Diatoms.f — Dr. P. Miquel discusses in detail the various modes in which diatoms multiply. The diminution in the size of diatoms is not in exact proportion to the number of bipartitions, which is retarded by the constant decrease in the thickness of the connectives. * Arm. Sci. Nat. (Bot.), xvi. (1892) pp. 91-256 (7 pis.). Cf. this Journal, 1892, p. 838. t Bull. Soc. Bot. France, xxxix. (1892) Sess. Extraord., pp. civ.-cxxviii. (1 pi.). t Ann. de Micrographie, iv. (1892) pp. 529-58 (9 figs.). Cf. this Journal, 1892, p. 655. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 515 Moller’s law with regard to the multiplication of the frustules, which prevails in Melosira, is certainly not true of all diatoms. In artificial cultures the propagation by means of auxospores can readily be followed out in many species of diatom, both filamentous and solitary. The restoration of form takes place habitually without the production of spores or sporanges. The protoplasm of the microfrustules escapes from the valves, and, at first enclosed in a membrane of cellulose, assumes first of all an irregular form, which gradually approaches that of the normal megafrustules. These primordial megafrustules acquire their regularity by bipartitions which immediately begin to take place in them. Whether the microfrustules are fertilized before germination must re- main at present undecided. j8. Schizomycetes. Effect of High Temperatures on Tubercle Bacilli.* — Drs. Forster and Bonlioff, though working quite independently, have examined the effect of temperatures below boiling point on tubercle bacilli. In Forster’s experiments the temperatures ranged between 40° and 95°, and Bonhoff ’s from 50° to 80°. The object of the former was to ascertain if the pasteurization of milk effectively destroyed tubercle bacilli contained therein. Both authors inoculated guinea-pigs in the peritoneal sac to demon- strate presence of living tubercle bacilli. Forster employed tuberculosis milk of cows, crushed tubercle and tuberculous sputum, while Bonhoff used pure cultivation of tubercle bacilli in calf’s lung broth with 4 per cent, of glycerin. On this medium the growth was extremely luxuriant in 10-14 days. Forster heated the tuberculous fluids enclosed in capillary tubes on a water-bath ; Bonhoff simply heated the pure cultiva- tions in a water-bath. The results of both authors are pretty well in accord. According to Forster, tubercle bacilli are killed when heated from 45-60 minutes at 60°, according to Bonhoff it only takes 20 minutes. At 70° they die in 6-10 minutes, while at 50° this result is not attained in 12 hours. Bonhoff noticed that the inguinal glands of animals which had been injected with cultures heated for 20 minutes at 60° underwent a slight enlargement. Origin and Presence of Alexins in the Organism.!— In an inter- esting and speculative paper Mr. E. H. Hankin suggests that the source of alexins, those substances which are the cause of the bactericidal power of the blood-plasma, is to be found in the eosinophilous granules in certain leucocytes. The hypothesis assumes a germicidal property existing in white corpuscles and blood-plasma, and the presence of special proteid substances, and endeavours to reconcile the opposing theories of Phagocytosis and Humoralism by showing that alexins are secretions from and by leucocytes. What are those bright highly refracting granules with greenish reflex and a love for eosin? They are the source from which the defen- * Hygien. Rundschau, ii. (1892) pp. 869 and 1009. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 293-4. t Centralbl. f. Bakteriol. u. Parasitenk., xii. (1892) pp. 777-83, 809-24 (6 fi^g.). 516 SUMMARY OF CURRENT RESEARCHES RELATING TO give proteids are drawn. They are the mother substances, in fact, of the alexins. Experiments to show the diminution in the number of these granules in the leucocytes following on an increase in the bac- tericidal power of the blood, and others to demonstrate that this germi- cidal action was greater before than after the excretion, would be required by the necessities of the case. Two series of such experi- ments are given in copious detail, and the conclusions arrived at are stated by the author to be simple but not altogether new. The cells of the body are able to resist the entrance of micro-organisms into the body in virtue of their phagocytic property, but there are other cells, “ alexocysts,” distinguished by the presence of eosinophilous granules, which secrete germicidal substances. Hence the eosinophilous leuco- cyte is a sort of wandering gland, and is comparable to the cells in the gastric mucosa, which secrete and excrete pepsin, so that the eosino- philous granules have their analogue in the zymogenic granules. Mucoid Change in Infusions.* — It is well known that many infusions are prone to become viscid, to throw down a deposit, or to evince some other form of deterioration. According to Herr E. Eitsert, the mucoid change is not associated with a degeneration of the leaves employed, but is set up by micro-organisms present in the air or in the water used to make the infusions. Microscopical examination showed the presence of moulds, yeasts, and bacteria ; from all of these cultivations were made in Digitalis infusion, and in the course of a few days it was found that bacilli had induced a viscosity, while other organisms were merely responsible for cloudiness, decoloration, or acidity. This observation was confirmed by obtaining pure cultivations through gelatin plates and inoculating infusions. From the behaviour of the organism on various cultivation media whereon it was found to exhibit marked polymorphism, e. g. long fila- ments, rods like anthrax, typical streptococci and other coccus arrange- ments, the author calls it Bacterium gummosum. The rod-like shape appeared in agar cultivations, and if these were kept at 20°-25°, endogenous oval spores were formed. By Gram’s method the bacilli were unstained, but the spores retained the colour. When transferred to potato the cultivations at first resembled those of anthrax, but after a few days diplococci became predominant. The streptococcus form appeared in cultivations made in cane-sugar diluted with 1 per cent, acetate of potash. B. gummosum is strongly aerobic, and its growth and form seem to depend largely on the composition and reaction of the nutrient medium. Thus alkaline gelatin is liquefied, and liquefaction is promoted if the plates do not contain too much gelatin, while an acid reaction and a high percentage of gelatin retard or prevent the liquefaction. Efficiency of Disinfectants at High Temperatures.^ — Dr. A. Heider finds that the disinfecting power of most disinfectants materially increases when they are used at a high temperature, and therefore all disinfectants * Ber. Pharmaceut. Gesell., 1. (1891) pp. 389-99. See Bot. Centralbl., 1892, Beih., p. 540. f Arch. f. Hygiene, xv. pp. 341-86. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 292-3. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 517 should bo used hot. Certainly where it is a question of destroying spores, cold fluids should be replaced by hot, and indeed by boiling hot ones. Hot solutions are not only safer and shorter in their action, but are more economical, as so much of the disinfectant is not required. For the disinfection of clothes the author states that the best pro- cedure is to place the linen, &c., for six hours in a 1 per cent, of lysol, then boil for half an hour, and afterwards wash in the ordinary way. Lysol was found to be the best and safest disinfectant. Escape of Bacteria with the Secretions.* — The experiments made by Prof. C. S. Sherrington as to the method of escape of bacteria from the circulation were made on mice, rabbits, and guinea-pigs which were inoculated with pure cultivations of various micro-organisms, e. g. B. antliracis , B. mallei , B. tuberculosis , B. cuniculicida, Sp. cholerse asiaticse , St. pyogenes aureus , and others, injected intravenously or subcutaneously. The urine, bile, and sometimes aqueous humour were afterwards examined. Taken in the aggregate the experiment showed that bacteria were some- times present in the secretions and sometimes absent ; that the presence in the secretions was to be associated with a more or less damaged condition of the secreting membranes, for these when healthy appear to be impassable to bacteria. These results seem to hold true more especially for pathogenic organisms, as these invariably appear in the secretion after a time, and their appearance is usually, though not invariably, accompanied by an escape of blood. Even if no actual blood can be detected these secreta may contain proteid when bacteria are present. The fact that animal membranes are permeable to the non-motile as well as to motile bacteria rather suggests that their outward passage is a passive transference than an active migration. Bactericidal Power of the Blood.j — The contribution of Dr. A. Bastin to the knowledge of the bactericidal power of the blood is essentially on the lines previously traversed by Nissen, who examined the bactericidal influence from intravenous injections of microbic emul- sions. Iu all his experiments the author used St. pyogenes aureus , and dogs were the animals experimented with. Though the method of the first part was the method of Nissen the results were diametrically opposite. The author found that after the intravenous injection of con- siderable quantities of microbic emulsion, the bactericidal influence was abolished or at any rate considerably diminished, and that this effect was due to the action of the toxins. The difference between the results of the two observers is possibly due to the fact that Nissen supposed the toxin to be alkaloid in nature and therefore soluble in water, whereas the author assumes the toxin to be albuminous. The natural inference that there is some relation between the dose injected and the diminution in the bactericidal power was corroborated by the experiments, and these also showed that the abolition and restoration of the functions were alike very rapid. When the bactericidal action was abolished for one microbe it was abolished for all others. After this the author enters upon the second * Journ. Pathol, and Bacterid. , iii. (1893) pp. 258-78. + La Cellule, viii. (1892) pp. 383-417. Cf. this Journal, ante , p. 372. 518 SUMMARY OF CURRENT RESEARCHES RELATING TO part of his task. In this the idea was to ascertain the bactericidal condition of the blood at different stages of infection, and especially at the moment when from being local the infection was becoming general. For this purpose local injections, e. g. into the pleural sac and into sub- cutaneous tissue, were made with bacillus of malignant oedema, Bacillus aerogenes , and St. pyogenes aureus. It was found that from being local the infection soon became general, and that under these circumstances the bactericidal influence was either abolished or much diminished. Secondly, that the degree of the diminution was in direct proportion to the intensity of the infection ; and thirdly, that the appearance of living organisms in the blood appears to coincide with a diminution in the bactericidal influence. Flies and the Transmission of Cholera.*— During the epidemic at Hamburg, Dr. N. Simmonds examined flies captured in the post-mortem room at the time the bodies were open. In these numerous comma- bacilli could be demonstrated. When the autopsies were over and the room washed up, the cholera bacilli were not found. In order to ascer- tain how long the cholera germ could be retained in flying insects, further experiments were carried on. It was found that they disappear in an hour and a half, a time sufficiently long to render their transmission to a considerable distance possible. Sphaerotilus roseus, a new red aquatic Schizomycete.f — Prof. W. Zopf found in the outfall of a sugar-refinery a new red Schizomycete belonging to the CladotrichesB, to which he has given the name Sphserotilus roseus, constantly associated with two other fungi. It forms long delicate filaments which coalesce into mucous strings, and these run into longer or smaller flakes which he found clinging to dead vegetable and animal matter. The filaments branch and exhibit a delicate sheath. They are composed of elongated cells of small diameter (0*7-1 /x), which ap- parently possess the power of swarming, and like other species of Clado - thrix may eventually split up into small segments. The red pigment is located in the cell contents. It can be extracted with alcohol, but strips of paper soaked with the red solution lose their colour on exposure to the daylight. The red constituent is soluble in ether, chloroform, petroleum-ether, benzol, &c., and the author thinks that he has isolated it by saponifying the alcoholic solution and treating it with petroleum- ether (a yellow non-crystallizing material). With sulphuric acid the colour becomes blue, and the spectrum of the solution exhibits two bands. Saccharobacillus Pastorianus4 — Herr H. van Laer has studied the micro-organism, first described by Pasteur in his £ Etudes sur la Biere,’ called Saccharobacillus Pastorianus. Its specific action is the turning of beer, which becomes mothery and acquires a disagreeable odour and taste. The organism did not get on well when cultivated on meat-water- gelatin, and very poorly on wort-gelatin, though if a little alcohol were added after liquefaction at 30° it did better, and similar results were * Deutsch. Med. Wochenschr., 1892, No. 41. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 237-8. Cf. this Journal, ante, p. 376. t Beitr. z. Morph, u. Phys. niederer Organismen (Zopf), Heft ii. (1892) pp. 32-5. j Zeitschr. f. gesammte Brauwesen, xv. (1892) pp. 340 et seq. See Bot. Centralbl., lii. (1892) pp. 330-1. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 519 obtained from pasteurized beer-gelatin. Yet on neither of these media did this organism thrive like yeast or other beer bacteria, the growth being only slow and the colonies of small size. Inoculations on fish-water-gelatin, milk-gelatin, wort-agar, and potato, failed to take. In mineral nutritive solutions the growth was very poor. Infection experiments showed distinctly that Saccharo- bacillus Pastorianus is the actual and efficient cause of the souring of beer; on unhopped beer the schizomycete grows better than on beer. The microbe is an acid-former, it decomposes carbohydrates, ferments cane-sugar, without previous inversion, into lactic acid, acetic acid, and alcohol. It also forms small quantities of formic acid and its homo- logues and homologues of ethyl-alcohol. The relative quantity of the fixed and volatile acids appears to depend on the composition of the nutrient medium. Saccharobacillus Pastorianus lives in the presence and absence of air. Ten minutes’ exposure to a temperature of 55°-60° C. suffices to sterilize a slightly acid beer wort which has not been hopped and has been infected with the bacillus. Hereditary Transmission of Immunity to Rabies.* — Prof. G. Tiz- zoni and Dr. Eug. Centanni record experiments made on three different litters with virus of rabies. Only the fathers were immunized, two to fixed virus, the third to street virus. The mothers were unprotected, although all three were vaccinated to tetanus. The authors conclude from these experiments, (1) that the father can transmit through the semen immunity to rabies ; (2) the transmission does not require any special properties in the mother ; (3) it is trans- mitted to all children alike ; (4) it is less than that possessed by the father ; (5) the immunity transmitted through the semen is more lasting than that acquired through the blood or milk. The authors go on to say that these experiments of theirs are in agreement with our present embryological knowledge, according to which the head of the spermatozoon, as male pronucleus, becomes fused with the female pronucleus of the ovule at the time of fertilization. Consequently, each new element which arises from the fission of the fertilized ovum must always possess a share, both of the maternal and paternal plasma, and of the properties inherent in them. With regard to the practical importance of these experiments, it is suggested that by carefully selecting dogs which have acquired immunity to rabies, this disease might eventually be extirpated. Chemotaxis of Leucocytes and Immunity.! — M. J. Massart found that when virulent cultivations were enclosed in capillary glass tubes, and inserted in the abdominal cavity, the less virulent possessed a stronger chemotactic action than the more virulent of the same species. Fowl-cholera, V. MetscJinikovi, hog-cholera, Bac. pyocyaneus, diphtheria, were used for these experiments, and the cultivations were both fresh and sterilized. The same results were obtained when virulent cultivations were diluted. No conclusion could be drawn as to the virulence of a cultivation from the strength of its harmful influence on leucocytes, and * Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 81-7. f Ann. Inst. Pasteur, 1892, p. 321. 520 SUMMARY OF CURRENT RESEARCHES RELATING TO the most important deduction is that the chemotactic substances in cultivations are not identical with the toxines. Structure and Spore-formation of Green Tadpole Bacilli.* — Dr. J. Frenzel reports on a bacillus which he observed in the end-gut of larvoe of Anura, especially if these were in bad condition ; he then describes their morphological characters, and discusses the central body which in this large bacterium offers favourable opportunity for satisfactory study. The view maintained by Butschli that the central body is to be regarded as the nucleus is confirmed. Spore-formation, which shows many peculiarities, is thoroughly described. The spores arise endo- genously, as nucleoid forms in the central body ; amitotic division is the usual course ; but it is not unfrequent to find two spores without observing a division into two cells. The finer structural relations of the plasma and of the membrane are also discussed, and a peculiar fila- mentous body is described ; this is found in bacilli containing spores, but at the opposite extremity ; its signification is quite unknown. Variability of Cholera Bacilli-t — Prof. Finkelnburg compared cholera vibrios obtained from different sources, — Paris and Hamburg epidemics and laboratory cultivations which originally were derived from India and from the outbreak at Genoa in 1884, for the pur- pose of ascertaining if there were any differences in the rapidity of their growth on gelatin plates: at what time liquefaction occurred in puncture cultivations ; what influence low temperatures had on their growth and viability ; whether lactose were fermented, milk coagulated, and cholera red formed ; how far they were dependent on the free access of oxygen; their action on red corpuscles, and the slight differences of shape. Only slight differences were found between the Parisian and Hamburg bacilli as regards rapidity of growth, while both were more resistant to lower temperatures and to the absence of oxygen than laboratory vibrios. They possessed, besides, greater power of inducing acid fermentation of lactose ; they were more poisonous to red corpuscles, and showed a greater tendency to form spirilla than the older species, which were also thinner and less prone to central bulgings. Bacteriology of Swine-plague- { — The bacteriological researches of Dr. B. Bang on swine-plague in Denmark date back to 1887, when the author isolated a bacterium pathogenic to mice and rabbits and fatal to a sucking pig in four days. This micro-organism grew very well on the usual substrata, and the cultures showed their identity with the American hog-cholera. The disease was at first very virulent, no less than 600 to 700 dying in a few weeks in one district. Later the disease became chronic and less virulent, so that only a comparatively small number of pigs died, though profound and extensive diphtheritic processes were found in the intestine. Often too a characteristic pneumonia was met with, the hepatized portions being firm and white, a yellowish demarcation line showing that the inflammation had ended in necrosis. No definite result was at first obtained from the examina- * Zeitschr. f. Hygiene, xi. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) p. 239. t Centralbl. f. Bakteriol. u. Parasitenk, xiii. (1893) pp. 113-7. j Maanedskrift for Dyrlaeger, iv. (1892-3) p. 194. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 203-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 521 tion of this chronic form, but afterwards the author was able to confirm the results of Salmon and Smith. Inoculations from the organs, especially the diseased intestines and mesenteric glands, disclosed a bacterium resembling that of 1887, but which was not pathogenic to mice or rabbits. It became evident from feeding pigs that it was a less virulent variety of swine-plague. The pigs sickened, and if killed after nine days croupous inflammation of intestines was found ; if killed later, small wounds and scars, close to the croupous membranes. When mice and rabbits were inoculated from pigs which were sick or dead of swine- plague, they usually died, but the swine plague bacterium was not found ; but in the exudation from serous membranes, in the blood and in the spleen, a bacterium, called by the author “ Vakuolebacillus,” was present. In the blood these bacilli showed as oval corpuscles, the poles only staining. In the exudation from serous membranes they were seen as plump little bodies, at one end of which was a vesicle. Experiments with the vacuole bacillus showed that its pathogenic action set up a fatal pleuro-pneumonia, but there was no affection of the intestinal tract. The vacuole bacillus is therefore undoubtedly identical with the swine-plague bacillus of Salmon and Smith, and certain forms of swine-plague are to be regarded as cases of mixed infection ; that is to say, hog-cholera and swine-plague may be simultaneously present in the same animal. Besides the specific organism of swine-plague another micro-organism, the necrosis bacillus, is very constant in the chronic form of this disease. It would appear that this exists in the intestine of healthy swine, but after the intestinal wall is weakened by the croupous inflammation it invades the deeper lying parts, producing there profound necrotic processes. The author main- tains that, (1) swine-plague is caused by a specific micro-organism ; (2) the pneumonias occurring in the chronic form of this disease are set up by another bacterium which apparently inhabits the nasal secretion of healthy pigs ; (3) the profound necrotic changes in the intestinal canal, as well as the necrotic foci in the pneumonic lungs, are due to the invasion of the necrosis bacillus. Pathogenic Action of Bacillus lactis.* — MM. R. Wurtz and R. Leudet, during some experiments relative to the pathogenic action of Bacillus lactis, established the fact that the characteristic claimed by Escherich as being distinctive of B. lactis aerogenes — fermentation in absence of air — was shared by Bacillus lactis. The two bacilli were therefore possibly identical. Guinea-pigs and rabbits inoculated with this bacillus died in a short time from severe diarrhoea with emaciation. On post mortem examination, well-marked ulcerative gastro- enteritis was discovered. The same, though less severe, changes were produced by the injection of sterilized cultivations. The toxic action appears to be dependent on the presence of proteids in the nutrient media, as bacilli cultivated on non-albuminous media exerted a much less pathogenic action, and this action is much diminished by heating. The toxin was not isolated. Cultivations in peptonized bouillon or alkaline pepton- solutions always became strongly alkaline, ammonia and other foetid substances being formed. The indol reaction was negative. * Arch. Med. Exp. et d’Anat. Pathol., iii. No. 4. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 275-6. 522 SUMMARY OF CURRENT RESEARCHES RELATING TO Tuberculosis and Leprosy.* — Dr. B. Rake records some experiments which seem to settle the long disputed question whether certain patho- logical lesions and morbid products found in cases of leprosy are tuber- culous or leprous. Guinea-pigs were inoculated with pulmonary tubercles from three cases of mixed leprosy. The usual appearances of guinea-pig tuberculosis were found. Cover-glass preparations showed bacilli indis- tinguishable from tubercle bacilli. Cultivations in glycerin-agar failed. As attempts to inoculate guinea-pigs with leprosy have always failed, it seems justifiable to conclude that the guinea-pigs became tuberculous from the infection derived from the pulmonary tubercles of the lepers. The author points out that the present position as to the relation of leprosy to tuberculosis is as follows : — Inoculation experiments have shown that the visceral nodules in lepers are tuberculous and not leprous. It is quite possible that leprosy and tuberculosis may be caused by the same bacillus, but this has not yet been proved. Morphology and Biology of the Tubercle Bacillus. | — According to Dr. F. Fischel the exciting cause of tuberculosis is a pleomorphous and variable micro-organism. The author bases his proposition partly on the observations of Metschnikoff and Mafucci, and partly on his own. He succeeded in demonstrating in the marginal zones of tubercle cultivations on agar and serum at 40°, long filaments, which were usually vertical, though occasionally short branches going off at an acute angle were observed. Occasionally forked and felt-like appearances were observed. In some cultivations of fowl-tubercle the author found drumstick-like forms, the pyriform expansions of which contained small, bright, round or oval forms, somewhat resembling anthrax spores, and these possibly are the representatives of gonidia. The form of the bacillus was found to be considerably influenced by the composition of the cultivation medium, e. g. blood-serum, agar, &c., containing different amounts of pepton, and charged with boric acid and thymol. Bacillus of Influenza.^ — Dr. L. Letzerich has constantly found in the blood of influenza patients very small free bacilli, which stained with hot methyl-violet, showing a tendency to red with darkly stained ends. Only potato cultivations succeeded. The author convinced himself that these bacilli were identical with those described by Pfeiffer and Canon. The number of bacilli found in the blood at the beginning of the disease is very great, but they gradually diminish as the disease passes away, and at the same time always stain more faintly. Bacterium pyogenes and B. coli commune.§ — Dr. Th. Reblaud, in the course of examinations of a case of cystitis, was struck with the resemblance exhibited by the micro-organisms so frequently found in infected urine, and so carefully studied by Clado, Halle, and Albarran, * Lancet, i. (1893) pp. 719-20. f Fortschr. d. Med., x. No. 22. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 124-5. X Zeitschr. f. Klin. Med., xx. No. 3. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 284-5. § Bull. Med., 1891, p. 1180. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) p. 285. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 523 to B. coli. Comparative researches confirmed the identity of the micro- organisms. Cultivation differences were referred to the influence of the natural nutrient medium. Parasites of Typhus Fever.* — Prof. S. W. Lewascheff availed him- self of the presence of an epidemic of typhus fever at Kasan to examine blood from the finger and from the spleen. Under a magnification of 2000-2500 small highly refracting cocci in active movement can be seen mixed up with the red discs. The motion is imparted by a long, thin, slightly curved flagellum or tail. The illustrations show red discs, tailed and tailless cocci. The former resemble spermatozoa in appear- ance, and their length is about the diameter of a red disc. Cultivations in serum hominis with 1 per cent, agar at 36°-37° were successful, but not under other conditions. The cocci developed only at the lower part of the puncture, and were therefore anaerobes. Under the Microscope the cocci thus bred were for the most part without a tail, with a green reflex, usually single, but occasionally in pairs, or even in chains. In young cultures the flagellated cocci, if transferred to bouillon in phy- siological NaCl solution, are extremely mobile. They are stained by Loeffler’s method, and with phenol-fuchsin. The quantity of these microbes ( Micrococcus exantJiematicus ) circu- lating in the blood appears to increase with the progress of the disease. Before the crisis involution forms appear. M. exantJiematicus is very dif- cult to stain, as the reagents seem to destroy it. Preparations treated with 2-3 per cent, osmic acid succeeded best. Streptococcus isolated from Scarlatina-blood, j — MM. D’Espine and de Marignac isolated a microbe from the blood of a patient who was attacked with “surgical scarlet fever” after an operation on the leg. The disease ran its usual course, followed by typical desquamation, and the wound healed quickly. The authors compare this streptococcus with ten others isolated from cases of erysipelas, abscess, diphtheria, pleuritis, broncho-pneumonia, angina catarrhalis, and healthy saliva. The three last belong to the group Streptococcus brevis ; the rest are long streptococci. The authors are, however, disinclined to draw a sharp line of demarcation between the two groups, though they suc- ceeded in differentiating the scarlatina cocci from other cocci. They took no account of the degree of virulence, but laid most stress on cul- tural characters, which on the whole accord with those of the scarlet fever coccus described by Klein. On blood-serum chain-formation is less marked, the cocci are smaller, 0 * 7 /x, and never bisected as in Str. longus. On bouillon the scarlatina Streptococcus behaves like Str. longus; "yet even in this case the individual joints are small, round, and the chains greatly contorted. On potato it forms long, twisted chains, without there being any naked-eye evidence of growth. Involution forms are common. Milk is coagulated in 2-3 days with acid-formation. On gelatin the growth has no special characters. The authors do not suggest any special connection with scarlet fever. * Wratsch, 1892, Nos. 11 aud 17. See Centralbl. f. Bakteriol. u. Parasitenk., xii. (1892) pp. 728-9 (1 fig.). t Arch, de Med. Exp., 1892, No. 4. See Centralbl. f. Bakteriol. u. Parasitenk., xii. (1892) pp. 762-3. 524 SUMMARY OF CURRENT RESEARCHES RELATING TO MICROSCOPY. Handbook of Microscopy.* — It would be almost impossible to put into a smaller compass the instructions needed by beginners in Micro- scopy than we find them to be presented in the pages of this book. But efficiency has not been sacrificed to brevity. The field covered is greatly narrowed by the wise omission from so purely elementary a treatise of the history and evolution of the Microscope, and of all attempts to epitomize the optical principles on which the instrument is built. The book introduces the amateur to his Microscope in a simple form, and explains competently, but in few words, the nature and use of apparatus. The plain and at the same time very practical and modern instructions given (pp. 50-6) on centering and illuminating with substage condenser will be welcome to many a tyro, and will prevent much needless waste of time. If the portion of this small volume devoted to the nature and use of the instrument be read with care by any one of ordinary intelligence, the initial work involved in the use of the Microscope will be done with far less trouble and disappointment than is usually the case. Nor is the feature of absolute utility a whit less lost sight of by Mr. Cole in the second part of the volume. Every line has its value, and he will have but little ingenuity and perseverance who will work honestly with this book before him and not succeed in making fair microscopic preparations and mounts in a short time. We cannot unconditionally subscribe to all that is laid down in this book ; but the divergencies have no great moment in anything apper- taining to the work of the beginner ; and even when we differ, and our differences are carried over to higher power work, we feel assured that the judgment of the authors is a judgment and not a mere opinion, and is therefore deserving of respect. This book will have the success it deserves. a. Instruments, Accessories, &c.f (1) Stands. Reichert’s Travelling Microscope.^ — In this Microscope, shown in fig. 60, the coarse-adjustment is by sliding in a socket, and the fine by a micrometer screw. It is very solidly built, can be put together very easily and occupies a very small space. It is provided with diaphragm and mirror, plane and concave, * 4 Modern Microscopy. A handbook for beginners, in two parts. 1. The Microscope, with instructions for its use by M. I. Cross. 2. Microscopical Objects: bow prepared and mounted, by Martin J. Cole.’ Balliere, Tindall, & Cox, London, 1893. f 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. % Reichert’s Catalogue No. 18 (!ow2). ZOOLOGY AND BOTANY MICROSCOPY, ETC. 525 9 9 0 Fig. 61. 526 SUMMARY OF CURRENT RESEARCHES RELATING TO Reichert’s Preparation Microscope.* — This instrument, fig. 61, is provided with an adjustment by rack and pinion, large brass stage, plane mirror adjustable on both sides, two leather covered hand-rests, and a doublet which magnifies 10 times. Reichert’s Catalogue No. 18 (1892). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 527 Reichert’s Movable Stage.* — In this stage, represented in fig. 62, the object can be displaced in two rectangular directions by means of the two screw-beads b arid c. It can be readily attached to and removed Fig. 02. from the ordinary stage. This stage is intended for the Reichert model No. II., but it can also be fitted by means of the screw i to any larger stage of the Continental type. A Sliding Carriage and Stage for the Microscope f — Mr. G. W. Brown, jun., says, “The following description and drawing of plan and section of an improved sliding carriage and stage for the Microscope may be of interest. If put into actual use it will, I hope, bring as much comfort and satisfaction as it has brought to me. After considering the qualities useful in a good stage, Dr. Dallinger concludes J that an efficient substitute may be found for a mechanical stage in what he terms a 4 super-stage/ so arranged that the bearings shall be glass, and friction reduced to a minimum. He says that 4 against its employment is the fact, first, that the slide is clipped into a rigid position ; and, second, that the aperture is too small to admit of the employment of the finger in moving the slide to assist in rapid focusing.’ He adds, 4 But these are defects which might certainly be overcome.’ The improved 4 super-stage ’ now described is believed to obviate these objections, and is not only 4 an efficient substitute ’ for a * Reichert’s Catalogue No. 18 (1892). ' t Amer. Mon. Micr. Journ, xiv. pp. 100-3. % Carpenter, 7th ed., p. 109. 528 SUMMARY OF CURRENT RESEARCHES RELATING TO mechanical stage, but a most desirable substitute for usual work with the Microscope ; permitting, as it does, absolute freedom of movements about a field for full two inches horizontally and one inch vertically, thus allowing ample room for even serial sections ; and possessing, as it does, exquisitely smooth sliding movements, over the stage proper of the Microscope, of almost absolute precision. My carriage and stage, made for me a year ago by Zentmayer of Philadelphia, after my own specifica- tions, is of such excellent workmanship as to give perfectly level and precise movements under a power of 2250 diameters (Zeiss 1/12 homo, immers., 18 compens. ocular). The drawing shows in fig. 63 a plan of the sliding carriage, and in fig. 64 a cross-section on a vertical central line. The stage should have Fig. 63. Fig. 64. two flat rails, one on each side of its aperture, slightly raised above the surrounding surface, on which the carriage slides ; and the stage may be square or round in shape, as preferred. The outlines of the carriage are shown by the full lines of the figures. Affixed to the bottom of the carriage are glass rails, A and B, of which the outlines and positions are indicated by dotted lines. These glass rails of the carriage slide on and over the metal rails of the stage. The circles a a and b show respectively knobs for holdfasts and a centering stop for object slide C, indicated by the broken lines of the figures. A spring clip c is provided, which can be swung against the upper side of the slide, as indicated by the dotted lines in fig. 63, to hold it securely in place when the stage is perpen- dicular or while it is rotated, or swung aside out of the way as shown by full lines. The slide rests with sufficient security against the ledge of the carriage when the stage is level or inclined, free from being clipped in a rigid position, justly criticized as objectionable by Dr. Dallinger. The carriage is kept in contact on the rails of the stage by the spring and ivory-pointed thumb-screw D, and the pressure thereby regulated. It will be observed that there is ample room in the opening of the sliding carriage, above the object-slides, to insert the end of the forefinger in quick focusing as recommended by Dr. Dallinger and practised by many microscopists ; and also that the object-slide is not slipped in a rigid position, but can be when desired. This opening also permits the use of wide angle, short focus or immersion substage con- EOOLOGY AND BOTANY, MICROSCOPY, ETC. 529 densers. By placing the forefinger on the holdfast a, the middle finger on the post of the spring clip c, and the thumb against the lowest corner of the sliding carriage, an object can be moved around and about the whole field of view, with the greatest facility and precision, and perfect control, while the other hand is constantly used at the same time in adjusting the focus as desired. Personally, I think such a carriage should be as light as possible, consistent with sufficient rigidity in con- struction. My own weighs only a little over one ounce ; the brass part, supporting the object slides C, being 1/25 in. thick, and that holding the broad glass rail A, double that thickness. The ledge against which the object slides lie, should, I think, be lower than their average thick- ness, to permit passing under high-power objectives so as to allow examination, even to the extreme edges. The ledge of my own carriage is 1/25 in. high, and I find this ample to securely support ordinary object-slides, and low enough to pass under the highest power ob- jectives. ’ The Society of Arts Microscope.* — The following is an account of the discussion on this subject which took place before a meeting of the American Microscopical Society last year. “ Prof. Claypole then read a paper on * The Society of Arts Micro- scope as a cheap Microscope.’ This instrument was designed and made forty years ago, and is still sold in England for about fifteen dollars. Mr. G. S. Woolman: What does Prof. Claypole consider cheap? Prof. Claypole: Twenty to twenty-five dollars. Mr. C. L. Griffith : What wages are paid by these Microscope- makers ? Prof. Claypole : I do not know ; we have no instrument made on the same plan. Mr. G. S. Woolman : I sold this instrument for many years at 22*50 dollars. It is a miserable instrument. The American makers make much better ones for 30 dollars. Dr. Blackham : When I first commenced to use a Microscope I used one of these instruments. It is a little better than the Craig Microscope, or a drop of balsam in a pinhole. The lenses are not as good as a 1 *50 dollar pocket magnifier — it is beneath contempt. The value of a stand is to hold the tube steady, and I would rather have a Jackson model and sliding-tube than that. The curious system of leverage it possesses magnifies every error of workmanship. The large model known as the Boss, which is similar to it, has been abandoned. The instrument I worked with was so badly made as to be worthless. Such traps are more likely to disgust a student with microscopy than to lead him on. Prof. Kogers : We have here two opinions — one that of an instructor who has successfully used the instrument in the class-room ; the other that of a dealer who formerly sold the instrument. It is only fair that both opinions should have their due weight. In regard to the choice between an instrument simple in form but of good mechanical construc- tion, as compared with a high-priced stand, I prefer the former. I use for most purposes a Bausch and Lomb stand costing about 12 dollars. It is well to keep in mind that nearly all the valuable work — e. g. in * Proc. Amer. Micr. Soo., xiv. (1892) pp. 32-3. 530 SUMMARY OF CURRENT RESEARCHES RELATING TO astronomy — has been done with instruments of comparatively small size. We may go further and say that a large part of the discoveries made in this science have been made with telescopes of moderate power. Dawes made his famous discoveries of double stars with a telescope having an aperture of only inches. The most of Herschel’s discoveries were made with a telescope of small aperture. It often occurs that solidity in mechanical construction more than compensates for increased magni- fying power. Mr. G. S. Wool man : The American makers furnish a better low-priced stand than the European. President Ewell : All Microscopes are good, but some are better than others. 1 would not select the Society of Arts instrument, but let us be tolerant. Some English authorities favour that stand. I would buy a model such as Brother Blackham has, but let us encourage every one to get a Microscope of some sort. Mr. Turner : I look at this matter from the standpoint of the manu- facturer. Men will accept, use, and pay for European work of a worse character than they will take from American manufacturers, and then criticize the latter. President Ewell : I want to say that the best work in the world is made in the United States. Professor Claypole : I agree with the President, but this instrument was made forty years ago ; Dr. Carpenter was the leading man in getting it made, and advocated it. I maintain that it is better the student should get such an instrument as this, and keep up to his work, than to drop it.” C3) Illuminating- and other Apparatus. Three new Accessories for the Microscope.* — Mr. E. H. Griffiths describes three accessories that are easily made by additions to the Griffith focus-indicator, which has already been described to the American Society of Microscopists. Fig. 65 is a rough sketch of the focus-indicator as now in use. Fig. 66 represents the same device attached direct to the nose-piece of the Microscope or to an adapter, and figs. 65 and 66 are introduced here simply to show that the indicator is a portion of the new accessories to be described. Fig. 67 is an object-holder to be used as an excellent substitute for stage-forceps, and for many objects it is much more convenient than the forceps. Near the bottom of the spindle-dropper of the indicator a small hole is drilled for the introduction of a pin, as illustrated in the sketch. The insect or other object for examination may be placed in focus by raising or lowering the dropper, and it may be turned over or placed in any position desired. This device may be used as a mechanical finger for arranging diatoms, &c. The pin in fig. 67 must be removed, and a cat’s whisker or other finger put in its place. It may be thrown into focus and out of focus by means of the Microscope adjustments. Fig. 68 represents a revolving diaphragm with as many apertures as * Proc. Amer. Soc. Micr., xiii. (1891) pp. 47-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 531 may be desired. It is made of thin metal, and may bo quickly attached to the bottom of the indicator-dropper and quickly placed in any position where desired. Other accessories made by additions to the focus-indicator will be described later. Fig. Go. Filar Micrometers.* — Prof. W. A. Rogers considers that there are two requirements in the construction of a good filar micrometer to which manufacturers have given too little attention, viz. equality in the diameters of the fixed and movable threads, and ease and uniformity in the movement of the measuring screw. The author considers that as regards uniformity in diameter, quartz fibres are far superior to spider lines. They appear to be truly circular and any required diameter can be easily obtained. The second difficulty may be met by the use of a long spring instead of the usual short stiff one for keeping the slide in contact with the end of the screw. For this purpose nearly the whole length of the frame can be utilized by the use of guide-pulley? at one end. thus allowing the spring to lie parallel with the sliding plate. Micrometers made for the author on this plan by Bausch and Lomb have given very satisfactory results. Reichert’s New Heating Apparatus. | —This apparatus, fig. 69, is used for the stage described on p. 383. It was designed by Dr. Spietschka in order to obtain a uniform heating of the hot stage during the course of prolonged investigations. A is a large vessel containing 15 Proc. Amer. Soc. Micr., xiv. (1893) p. 132. f Reichert’s Catalogue No. 18 (1892). 532 SUMMARY OF CURRENT RESEARCHES RELATING TO water which passes into the spiral B, where it is heated to a given tem- perature by a Bunsen burner provided with an automatic regulation of the Fig. 69. A gas supply. By means of the stop-cock H the rate of passage of the hot water to the hot stage, and consequently the temperature of the latter, can be conveniently regulated. Reichert’s new Cover-glass Measurer.* — With this instrument, represented of half its natural size in fig. 70, the most exact measure- Fig. 70. ments of O' 01 to 8 mm. can be quickly and conveniently made. The clamp b, in which the cover-glass to be measured is fixed, is opened by a slight pressure upon the lever a. Sir David Salomons’ Electric Lantern. — The following figures f represent this lantern as shown by Sir David Salomons at the May Meeting of this Society (see ante, pp. 383-4, 424-6). Fig. 71 shows the instrument with the polariscope on the right and the Microscope on the left. Fig. 72 gives another view with the Microscope on the right, and also showing the third front. * Reichert’s Catalogue No. 18 (1892). t We are indebted to the Camera Club for the use of the cliches. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 533 The lantern with its apparatus can be rapidly erected. All parts are interchangeable, and only attached with one screw. No support is Fig. 71. required for an y apparatus outside the lantern. Support is obtained by straining-rods from portions which project far beyond the lantern case Fig. 72. to pillars attached at the top of the lantern. In other words, the same principle is employed which is now so much in vogue with bridges, i. e. the cantilever principle. SUMMARY OF CURRENT RESEARCHES RELATING TO 534 (4) Photomicrography. New Heliostat.* — Dr. Lyman S. Deck writes as follows: — “This simple and inexpensive form of heliostat, some idea of which can be gained from the accompanying illustration, is designed more especially Fig. 73. A, Triangular frame on levelling screws B. D, Plate of clock movement. C, Brace for inclining movement at proper angle. E, Posts on which clock-plate turns. F, Mirror frame on joint Gr. H, Hour spindle carrying wheel with 10 cogs. I, Wheel for reversing the motion of the mirror. J, Wheel having 40 cogs on spindle carrying the mirror. K, Brass case to protect the clockwork from dust. for use in photomicrography and with projection apparatus. It is con- structed on a principle similar to the equatorial telescope, and consists essentially of a mirror revolving on an axis parallel to the axis of the Proc. Amer. Soo. Mier., xiii. (1892) pp. 49 and 50. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 535 earth and in an opposite direction to the earth and with one-half its velocity, or making a complete revolution once in 48 hours. It may- be made from the works of a common clock, having a balance, in the following manner : — First remove the striking parts of the clock and procure three cog- wheels,* one having 10 cogs, one 40 cogs, and the third wheel any con- venient number. Now fasten the one having 10 cogs to the spindle of the hour-hand and in its place. Next, to carry the mirror, make a spindle about three inches in length and fasten the wheel of 40 cogs to it at such a place that when it is in its place in the framework of the clock it will be on a level with the wheel of 10 cogs, and then drill holes to receive it in the framework of the clock, taking great care to have it sit perpendicular to the frame when in place. Now attach the third wheel to the framework so that its cogs will match with the other two wheels and cause the spindle carrying the mirror to revolve in the same direction as the hands of the clock. A plane mirror may be attached to the spindle by a ball-and-socket joint or any convenient means. Now make a flat tripod base of iron with three levelling screws, and attach the clockwork to it by means of a hinge so that it can be ele- vated to correspond to the latitude of the place. To use the instrument, set it up with great care exactly north and south and elevate the axis carrying the mirror by means of a protractor and plumb to correspond to the co-latitude of the place, so that the axis points directly to the north star, and then adjust the mirror so as to reflect the light to the desired place. This simple apparatus, if well made, will answer every purpose of the more expensive heliostats and will practically keep a beam of sun- light in a constant direction for hours at a time. As reflection from a glass mirror is not perfect, it is better in practice to not reflect the light at an angle too acute to the surface of the mirror.” Photomicrographs by Gas-light-t — Dr. G. M. Sternberg advocates the use of gas-light as a satisfactory artificial light for photomicrographic work. The objections to the use of the oxy-hydrogen lime-light are the considerable expense attending it and the inconvenience resulting from the necessity of frequently renewing the gas-supply when much work has to be done. The electric light is also very expensive unless an electric plant is at hand, and even then it may not be available during the day. Admirable results have been obtained by the use of an oil- lamp ; but to photograph bacteria, &c., which have been stained, coloured screens must be used, and then, owing to the loss of light, the time of exposure must be considerably increased. Under these circumstances the author was induced in 1889, when preparing a report of the investigations which he had made on yellow fever in Cuba, to experiment with gas-light, and obtained very satis- factory results. The objective used was the 3 mm. oil-immersion apochromatic of * “ Grooved band- wheels. may also be used.” t Proc. Amer. Micr. Sue., xiv. (1893) pp. 85-90. •536 SUMMARY OF CURRENT RESEARCHES, ETC. Zeiss, and the eye-piece his projection No. 3. An amplification of 1000 times was employed. Most of the photographs were made from preparations stained with a simple aqueous solution of fuchsin. A yellow screen, prepared by coating a plate ol glass with a film of negative varnish in whicli tropaeolin had been dissolved, was placed at the back of the achromatic condenser. Orthochromatic plates manufactured by Carbutt of Phila- delphia wrere used. The arrangement of the apparatus is seen in fig. 74. A is the camera, with pyramidal bellows front supported by the heavy wooden Fig. 74. block B, whicli can bo pushed back so as to enable the observer to place his eye at the eye-piece of the Microscope ; G is the large Powell and Lealand stand, and D the Abbe condenser supported upon the substage ; E is a thick asbestos ^screen for protecting the Microscope from the heat of the gas-battery F. $ The gas-burners are arranged in a series with the flat portion of the flame facing the aperture in the asbestos screen. The light is reflected in the right direction by the concave mirror G. The focusing is effected by means of the rod I, which carries at one extremity a grooved wheel H, connected by a cord with the fine-adjustment screw of the Microscope. The focusing-wheel J may be slipped along the rod I and retained in any required position by a set-screw. To avoid oscillations, soft rubber cushions were placed under the whole apparatus. 'Reichert’s New Photomicrographic Apparatus.* — This apparatus can be used with the highest magnifications either in the vertical (figs. 75 and 76) or horizontal (fig. 77) position. For use in the horizontal position with very high magnification, the object is first adjusted in the Microscope as in fig. 76, and then the apparatus is reversed as seen in fig. 77. The light-proof connection between Microscope and camera is effected by the socket Y and the adjustable connecting piece F. The final correction of the fine-adjustment is effected by means of the string, * Keicherts Catalogue No. 18 (1892). I Fig. 76. I Fig 538 SUMMARY OF CURRENT RESEARCHES RELATING TO seen in fig. 77, wbicli acts upon the lever a fitted to the micrometer screw. On the glass plate of the camera four squares are etched, so that it can be simultaneously used as a transparent and as a ground glass plate. The total length of extension of the camera from Microscope stage to glass plate amounts to about 85 cm. 7 (5) Microscopical Optics and Manipulation. Theory of Optical Instruments."' — The appearance of this hook by Dr. S. Czapski will be welcomed by all microscopists who possess the mathematical knowledge necessary for the due appreciation of Prof. Abbe’s theories on the formation of the microscopic image. The book is really an abstract of the articles which the author contri- buted to Prof. Winkelm aim’s ‘ Hand- buch der Physik.’ It is not, however, a text-book of optics, as only those points are dealt with at length which, in the author’s opinion, are not to be found adequately treated elsewhere. The main object of the book is to demonstrate the advance s which have been made in our understanding of the behaviour of optical instruments owing to the observations and theories of Abbe. The phenomena of diffrac- tion and the famous diffraction theory (ihe “ Abbe theory ” proper), however, are not discussed in this book, but are reserved for a subsequent work. After a preliminary chapter deal- ing with the general principles of geometrical optics, there follows a full discussion of the Abbe theory of the formation of images. This is succeeded by a chapter treating of the theory of spher’cal aberration and the conditions necessary for its compen- sation (achromatism). Prisms and * ‘ Tlieorie der Optisehen Instrumente nacli Abbe,’ Breslau, 1893, 8vo, 292 pp., 91 figs. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 539 systems of prisms are next considered. Then under the head of limi- tation of the rays and the properties of optical instruments dependent upon it, the questions of perspective, magnification, penetrating power, brightness of images, the aperture and limits to the resolving power of optical instruments are passed in review. These general theories form the foundation for the special theory of optical instruments, the most important of which, viz. the eye, projecting systems, lens, Microscope and telescope, are then discussed in detail ; for each of them the dioptric effect and the factors on which it depends are determined, and, in the case of the artificial instruments, a critical and historical review is given of the most important types of con- struction. The concluding chapter of the book is devoted to a description of the methods employed in the determination of the constants of optical instruments. At the end of each chapter is a list of the literature bearing upon the subject which has been discussed. On the Subjective Magnitude of the Monocular and Binocular Images in the Hand-lens.* — Dr. Yves Delage gives an explanation of the increased magnification which results when both eyes instead of one only are used in examining an object through a hand-lens of large diameter. This increase in magnification must evidently be a subjective phe- nomenon, since the retinal image of the second eye is equal to that of the first. In such a question of magnification, then, there are two things to be distinguished : the real magnitude of the retinal image and the subjective sensation of the magnification. As regards the first point. According to the text-books the lens should be placed so that the image is formed at the minimum distance of distinct vision. This may be an advantage, but is not a necessity, for between eye and object there is a considerable range of distance in which the lens will furnish sharp images ; and this is also the case if the eye is displaced with respect to the lens. Similarly for each fixed distance of lens from the eye, there is a series of positions of the object giving sharp images and different magnifications ; and finally there is a series of positions of the head giving distinct images. The real magnification, then, depends on the relative positions of three factors : object, lens, and eye. Now for a given position of the lens L L' (fig. 78) with its foci F F and of the object 0 O', the image 1 1' has a position and magnitude fixed and independent of the eye which perceives it. This image can be considered as a real object seen by the eye with- out the lens. It is such that any ray I C passing from any one of its points to the eye and meeting the lens in K is real in its part K C which represents the refracted ray corresponding to the incident ray 0 K. This image 1 1' can be seen by the normal eye from an infinite distance up to the punctum proximum. As the distance of the eye increases, the angle beneath which it sees * Arch. d. Zool. Exp., i. (1893) pp. vi.-xiii. 2 p 1893. 540 SUMMARY OF CURRENT RESEARCHES RELATING TO I 1', i. o. the retinal image, diminishes. Thus in order to obtain images as large as possible, the eye must be placed as close as possible to the lens. Now let the distance of the lens from the object be varied. The more the lens is separated from the object, the nearer is the latter to the Fig. 78. f ocus and the greater is the image. But the retinal image diminishes as 1 1' recedes, and in fact 1 1' recedes more rapidly than it increases, Ip'. p' for the formula — = - put in the form 1 = 0— shows that, 0 being Op p constant, in order that I may vary uniformly with p\ p must be constant. This is not the case, however ; p varies much less rapidly than p\ but in the same direction as it. In order to obtain the largest retinal image, then, the lens must be approached to the object. But in this direction there is a limit, for as p diminishes, so docs pr, until it becomes equal to A, the minimum distance of distinct vision. To put this in a more mathematical form, let A be the distance C Q of the lens to the nodal point of the eye, and consider only the half of the figure situated above or below the optic axis M m. The retinal image is measured by the tangent of the angle a of the extreme rays. But tan a = — — - . The retinal image will therefore be so much p + A greater as A is smaller ; which shows that the eye must be placed as near as possible to the lens. On the other hand, from the similar triangles F' Q H, in which HQ = 0 and Q F' = /, and F'MI: we have .*. tan a = 0 / i p'+f O f X = constant x £&£ p + A p' + A Now by varying p\ the fraction £±f p’ 4- A will vary in the same direction or in the opposite, according as it is less or greater than unity. Thus tan a will be a maximum when p' is a minimum, so long as A is less than ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 541 /, and this will be the case unless the lens is very thick. It follows from this that the myope can see with the lens more details than the emmetrope, since he is able to make p' less. On the other hand, however, the magnification defined by g is less for him than for the emmetrope, for - = - O i which shows that — is a maximum when p' is. _ p' O' + /) p' + f p'f f ’ This is only an apparent contradiction, for the service rendered to the emmetrope by the instru- ment can be greater than that rendered to the myope, without the latter ceasing to keep the advantage over the former. Now to consider the second point, viz. the subjective sensation of the magnification of images. Besides the magnitude of the retinal image we have as another element the distance. All objects seen under the same visual angle ought to appear equal, but we feel them more or less great because we refer them more or less far in the angle. Thus a doll of 15 cm. seen at 1 metre appears smaller than a woman of 1 m. 50 seen at 10 metres, although they furnish equal retinal images. So inversely a man appears as large at 5 metres as at 10. To what distance then are the images furnished by the lens referred ? In monocular vision the images furnish no direct indication as to their situation on the visual ray. Indirectly we are guided by com- parison with other objects in the field of view and also by the effect of accommodation, but this element of judgment is not very precise. In the case of the lens, if it alone influenced us, we should refer the image to its true distance, but other effects intervene which cause us to modify our impression. According to the author’s experience we refer the image nearly to the position occupied by the object which furnishes it. Thus in examining with a lens an object on a table, the field of the lens does not appear to be sunk into the table as would be the case if the retinal image was referred to the distance of the virtual image. The feeling of the continuity of the parts seen in the lens with their pro- longation beyond the field dominates the less intense impression of the effect of accommodation. The resultant sensation is doubtless a com- promise between the organic sensation and the corrected sensation, but much nearer the latter than the former, at least with persons who frequently make use of the lens. Thus the image seen with the single eye is always estimated below its true dimensions. When, however, both eyes are opened, the con- vergence of the optic axes furnishes instantly a precise and intense indica- tion which dominates all the preceding vague approximations ; the image is referred to its true distance and consequently appears greater. Thus in fig. 79 the rays starting from the point N which, without the lens, would make an angle Cx N C2, form after refraction the smaller angle Cj M C2. The eyes have the same direction as if 0 O' were at 1 1'. With a single eye C the image is referred in the angle a to the distance C P, and Ix P measures its apparent magnitude ; while with two eyes Cx and C2 it is seen beneath the same angle at a distance C M, and its apparent magnitude is represented by I M. 2 p 2 542 SUMMARY OF CURRENT RESEARCHES RELATING TO From fig. 79 we have from C N. IM m3 A- + fQr q p ^oeg nQj. gengibly A. +i? Replacing p by its value drawn from the equation - — i = & V + / V V f IM X+i/ , *>'2 _t , 1 + ap' + a/+p'/ + a / x/' “V+/ p'2 Fig. 79. This shows that the binocular image 1 1' appears so much greater with respect to the monocular image Ix 1/ as A and f will be smaller and jp' greater. To see the phenomenon under the most favourable conditions therefore, it would be necessary to take a lens of short focus, separate the object as far as possible from the lens, and place the eye close to the lens. II' For the normal eye, since p' is without limit - - — can become equal -*-i m to -j- oc ; but actually the binocular image never appears more than double the monocular, for when the virtual image is very far from the eye, the sentiment of the reality of things is opposed to the idea that the subjective image which represents it is very far from it. Numerical Aperture. — Dr. M. D. Ewell writes as follows on this subject : * — “ It is not proposed in this paper to enter upon any theoretical dis- cussion, but to give the results of actual measurements of the aperture of such objectives of different makers as I have been able to procure for that purpose. The measurements were made with an Abbe apertometer, which will be found figured and described on p. 24 of Zeiss’s English Catalogue, 1891, as ‘No. 2.’ | I intended to repeat the measurements on another apertometer of * Proc. Amer. Micr. Soc., xiv. (1892) pp. 44-7 (2 figs.), t See also Journ. Roy. Mier. Soc., Jan. 1878, p. 19; 1880, p. 20. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 543 my own construction, and to include the results of this paper, but the pressure of professional duties has prevented the completion of this work in time for this meeting. A description of this piece of apparatus may, however, not be inappropriate. See fig. 80. Fig. 80. Fig. 81. A represents an iron plate, 20 in. square and 1/2 in. in thickness, planed as flat as possible on its upper surface; B represents a brass circle 13 in. in diameter, graduated to one-half degrees, and turning around its centre C; D represent two opposite verniers, reading to single minutes of arc. In practice, however, these are entirely unnecessary, as the unavoid- able errors of measurement must exceed the least count of the verniers. The centre is read, therefore, simply to one-half degrees or, if desired, by estimation to three minutes of arc. In fig. 81, A represents a brass slide with a small hemispherical lens B, burnished into an opening in its centre. The centre of this lens is indi- cated by a very small circle marked on its plane surface with a diamond while in the chuck on which it was turned up. This portion of the apparatus was made for me by Spencer and Smith, of Buffalo, New York. Table describing Objectives. 544 SUMMARY OF CURRENT RESEARCHES RELATING TO o 6 o o bO 03 © j- j. CZ »>? O Si pO i-i T3 03 6 6 gg *?o stated by Prof. W. A. Rogers, who purchased it for me. t Collar at 1°, best point of adjustment. X Approximately. describing Objectives — continued. ZOOLOGY AND BOTANY. MICROSCOPY, ETC. 545 o . - o 2 £ cfo Q^r !q W3 X c3 ?0 S 03 #o O CD to O *c3 GfJ c3 .2 oT s © -4-3 O to 03 3 a ci O .2 s R_r O 0 'a! cc w K d 0 -tJ r aa Q5 w 5P £ fl Sh P CO CO CO ^ CO CO coco fc 8 (2 oj gj 3 3 ^ o J 05 CD (N 7 18.- —Nodosaria ( Gl .) humilis Roemer. x 50. 77 19, 20. „ 77 mutabilis Reuss. x 50. 77 21. 77 77 cylindracea Reuss. X 50. 77 22. 77 radicula Linne, var. Jonesi Reuss var. X 50. 77 23. oligostegia Reuss. x 50. 77 24. 77 (Z>.) expansa Reuss. x 60. 77 25. 77 77 farcimen Soldani sp. x 60. 26. 77 77 soluta Reuss. x 50. 77 27. 77 77 „ var. discrepans Reuss var. X 50. 77 28. 77 77 „ var. pulchella var. nov. X 60. 77 29. 77 77 gracilis d’Orbigny. X 60. 77 30. 77 77 Lorneiana d Orb. (curved var.). X 60. 31. 77 77 „ „ (straight var.). X 50. 77 32. 77 77 pauperata d’Orb. x 60. 77 33. 77 77 consobrina d’Orb. X 60. 34. 77 77 cylindroides Reuss. x 60. 77 35. 77 77 hamulifera Reuss. x 60. 77 36. 77 77 xiphioides Reuss. x 60. 77 37. 77 77 legumen Reuss. x 50. >7 38. 77 7» Boemeri Neugeboren. x 60. Plate IX. „ 97 17 97 79 77 77 77 77 77 77 77 77. 77 77 77 77 1. — Nodosaria (ZA) communis d’Orbigny. x 60. 2. 77 „ mucronata Neugeboren. x 65. 3. S9 „ costellata Reuss. X 60. 4. 79 „ raristriata sp. n. x 60. 5. 77 hispida d’Orbigny. X 50. 6. 77 perpusilla sp. n. x 75. 7. 99 bambusa sp. n. x 50. 8. 77 (ZA) intercellularis Brady, x 75. 9. 77 sceptrum Reuss. X 60. 10. 97 internotata sp. n. x 60. 11. 79 (ZA) tubifera Reuss. x 60. 12. „ Zippei Reuss. X 60. 13, 14. 77 „ paupercula Reuss. x 60. 15. 99 „ Fontannesi Berthelin. x 60. 16. 99 „ obscura Reuss. x 60. 17, 18. 77 inflata Reuss. X 60. 19, 20. (ZA) tenuicosta Reuss. X 60. 21 prismatica Reuss. x 60. 22, 23. „ orthopleura Reuss. X 60. 24. 77 tetragona Reuss. x 60. * Common in thin slices of Wenlock limestone, Dudley (F. C.) ; and in the Woolhope Shales, Malvern (Brady). Foraminifera of the Gault of Folkestone. By F. Chapman. 581 Lagena apiculata Reuss, plate VIII. figs. 2 a, b, and 3 a, b. Oolina apiculata Reuss, 1850, Haidinger’s Naturw. Abhandl., vol. iv. p. 22, pi. i. fig. 1 . Lagena apiculata , var. elliptica Renss, 1862, Sitznngsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 35, pi. ii. fig. 2. L. apiculata Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 319, plate i. figs. 4-8, 10, 11. L. apiculata Brady, 1884, Chall. Rep., vol. ix. p. 453, figs. 4, 15-18. L. apiculata Burrows, Sherborn and Bailey, 1890, Journ. Roy. Micr. Soc., p. 555, plate IX. figs. 6, 7, 9-11. This somewhat variable form is widely distributed through the Gault, and is perhaps the commonest of all the Lagense from that formation. The two specimens figured give an idea of the variation in the shape of the test ; the pyriform variety, with a circular aperture, is much more common than the globose form with bordered fissure. It has been found in beds as old as the Lias ; and in recent deposits it affects shallow and deep water alike. In the Cretaceous rocks it has been found in the North-German Gault* and the Belemnitella mucronata bed of Galicia (Reuss) ; in the Red Chalk of Speeton, &c. (Burrows, Sherborn and Bailey) ; and in the Chalk of the North of Ireland (Wright). It is found in the Gault of Folkestone in zone i. specimen b, very rare ; zone ii., specimen a, very rare ; zone iv., very rare ; zone v., very rare ; zone vii., very rare ; zone x., very rare ; zone xi., 55 ft. from the top, rare ; 50 ft., frequent ; 45 ft., very common ; 40 ft., very rare ; 35 ft., rare ; 30 ft., frequent ; 25 ft., frequent ; 12 ft., rare ; 6 ft., very rare. Lagena apiculata , var. emaciata Reuss, plate VIII. figs. 4, 7. Lagena apiculata , var. emaciata Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 319, pi. 1, fig. 9. L. apiculata , var. emaciata Burrows, Sherborn and Bailey, 1890, Journ. Roy. Micr. Soc., p. 555, plate ix. figs. 8, 12, 13. This variety has been found in the Septa ria-clay of Pietzpuhl (Reuss.) ; and in the Red Chalk of Speeton (Burrows, Sherborn and Bailey). It occurs in the Gault at one horizon only ; zone xi., 45 ft, from the top, rare. Lagena Isevis Montagu sp., plate VIII. fig. 5, Vermiculum Iseve Montagu, 1803, Test. Brit., p. 524. Lagena Isevis Brady, 1884, Chall. Rep., vol. ix. p. 455, pi. lvi. figs. 7-14, 30. L. Isevis Burrows, Sherborn and Bailey, 1890, Journ. Roy. Micr. Soc., p. 555, plate IX. fig. 3. The specimens of this Foraminifer which occur in the Gault are somewhat variable in size, and are occasionally smaller than the one * N.B. The Gault of Germany is equivalent to the Gault and Lower Greensand of England. 2 s 2 582 Transactions of the Society . figured. Some of the specimens have the lip of the neck everted, similar to those found in the Red Chalk. This species is one of the oldest fossil forms of Lagena , occurring in strata from the Silurian* and upwards. It is found in zone iv., very rare ; zone v., very rare ; zone xi., 35 ft. from the top, very rare ; 30 ft. rare. Lagena gracillima Seguenza sp., plate VIII. fig. 6. Amphorina gracillima Seguenza, 1862, Foram. Monotal. Mess., p. 51, plate i. fig. 37. Lagena gracillima Jones, Parker and Brady, 1866, Monogr. Foram. Crag, p. 45, plate i. figs. 36, 37. L. gracil- lima Brady, 1881, Chall. Rep., vol. ix. p. 456, plate lvi. figs. 19-28. Hitherto this species has not been found in beds older than the Miocene. The specimens found in the Gault are very small and were obtained by very careful examination of the finest washings. It occurs in the Grault in zone xi., 50 ft. from the top, very rare. Lagena aspera Eeuss, plate VIII. fig. 8. Lagena aspera Beuss, 1861, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xliv. p. 305, plate i. fig. 5. L. aspera Brady, 1884, Chall. Bep., vol. ix. p. 457, plate lvii. figs. 7-10. This species is rather uncommon in the Gault. It does not vary greatly in contour from the specimen figured, but the apiculate portion is usually absent. Lagena aspera , though new to the Gault, is known as a fossil from Middle-Liassic beds, the Oolite, Upper Chalk, Tertiary beds, and also from recent deposits. In the Gault it occurs in zone iii., very rare; zone xi., 45 ft. from the top, frequent; 12 ft., rare. Lagena hispida Beuss, plate VIII. figs. 9 a , h, 10 a , h. Lagena hispida Reuss, 1858, Zeitsclir. d. deutsch. geol. Gesellsch., vol. x. p. 434. L. hispida Beuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 335, plate vi. figs. 77-79. L. hispida Brady, 1884, Chall. Bep., vol. ix. p. 459, pi. lvii. figs. 1-4 and plate lix. figs. 2, 5. A well distributed and tolerably common form in the Gault, though here recorded for the first time. It has also been found in the Middle Lias of France and in most Tertiary deposits. In recent soundings it occurs in shallow water and at depths varying from 129- 1900 fathoms. The Gault specimens vary somewhat in shape, and are represented on the accompanying plate by drawings from the two principal types, viz. the elongated or flask-shaped form, and the globose form. This species is found in the Gault in zone ii., specimen a, very rare ; zone iii., common ; zone iv., very common ; zone v., From the Woolhope Beds (Brady). Foraminifera of the Gault of Folkestone. By F. Chapman. 583 very common ; zone vi., rare ; zone vii., very common ; zone xi., 50 ft. from the top, frequent ; 45 ft., very rare ; 40 ft., very rare ; 35 ft., rare ; 30 ft., very rare; 25 ft., rare ; 12 ft., rare. Lagena sulcata Walker and Jacob, plate VIII. fig. 11. Serpula ( Lagena ) sulcata Walker and Jacob, 1798, Adams’s Essays, Kanmacher’s ed., p. 634, plate xiv. fig. 5. Lagena sulcata Parker and Jones, 1865, Phil. Trans., vol. civ. p. 351, plate xiii. figs. 24. 28-32, and plate xvi. figs. 6, 7. L. sulcata Brady, 1884, Chalk Bep., vol. ix. p. 462, plate lvii. figs. 23, 26, 33, 34. This well-marked species is here recorded for the first time from the Gault. It also occurs fossil in shales of Upper Silurian age; in the Lias of Yorkshire (Blake) ; in the Maestricht Chalk (Parker and Jones) ; and in various Tertiary beds ranging up to the present time. In recent deposits it is found in all latitudes, and in shallow- water to depths as great as 2750 fathoms. In the Gault it is found in zone ii., specimen c, very rare ; zone iv., very rare. Lagena acuticosta Beuss, plate VIII. fig. 12 a, h. Lagena acuticosta Beuss, 1861, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xliv. p. 305, plate i. fig. 4. L. acuticosta Beuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 331, pi. v. fig. 63. The solitary specimen found in the Gault agrees with the form described by Beuss, with the exception that the Gault specimen has thinner costse. It is very closely allied to L. sulcata. Previously recorded from the Maestricht Chalk (Beuss) ; and the Septaria-clay of Pietzpuhl (Schlicht). Found in the Gault in zone v., very rare. Lagena gracilis Williamson, plate VIII. fig. 13. Lagena gracilis Williamson, 1818, Ann. and Mag. Nat. Hist., ser. 2, vol. i. p. 13, pi. i. figs. 3, 4. L. gracilis Brady, 1884, Chalk Bep., vol. ix. p. 464, plate lviii. figs. 2, 3, 7-10, 19, 22-24. This elegant and somewhat variable form is found in the Gault series for the first time. Its variation consists in the relative length of the neck, and in the degree of development and thinness of the costse. In one example, at least, the test possesses the typical mucro- nate or apiculate aboral end ; whilst the others have that end den- ticulate. This species has also been found in the Chalk of Biigen (Marsson) ; in the Septaria-clay of Pitzpuhl (Beuss and Schlicht) ; and in various Pliocene and Post-pliocene beds. As a recent form it is well distributed and is found to as great a depth as 2775 fathoms. In the Gault it occurs in zone ii., specimen a , very rare ; zone iii., very rare ; zone xi., 20 ft. from the top, very rare. 584 Transactions of the Society. Lagena alifera Reuss, plate VIII. fig. 14. Lagena alifera Reuss, 1870, Sitzungsb. d. k. Ak. Wiss. Wien, vol. lxii. p. 467, No. 11 ; Schlicht, 1870, Foram. Pietzpubl, plate iii. figs. 15, 16, 21, 22. One specimen was found which resembles Reuss’s L. alifera in having wing-like costee ; the shape of the shell is however somewhat different, since, instead of being flask-shaped, as in Reuss’s figure, it is elliptical, with pointed extremities. It does not appear necessary, however, to make any distinction on account of this variation in form from the type. The specimen was found in zone ix. Lagena striatopunctata Parker and Jones, plate VIII. fig. 15. Lagena sulcata , var. striatopunctata Parker and Jones, 1865, Phil. Trans., vol. civ. p. 350, plate xiii. figs. 25-27.' L. seriato- granulosa Reuss, 1870, Sitzungsb. d. k. Ak. Wiss. Wien, vol. lxii. p. 468, No. 16; Scblicht, 1870, Foram. Pietzpuhl, plate xxxviii. fig. 20. L. striatopunctata Brady, 1878, Ann. and Mag. Nat. Hist., ser. 5, vol. i. p. 434, plate xx. fig. 3. L. striatopunctata Brady, 1884, Chall. Rep., vol. ix. p. 468, plates lviii. figs. 37, 40. The specimens from the Gault are very typical. The aperture is entosolenian and the perforate costae vary in number from 11-15. This species has also been found in the Phosphatic Chalk of Taplow (Chapman) ; in the Septaria-clay of North Germany (Schlicht) ; in the Post-tertiary deposits of the West of Scotland (Robertson), and of the North-east of Ireland (Wright). As a recent form its bathy- metrical range is not restricted, and it is also a widely distributed species. It is found in the Gault in zone iv., very rare; zone xi., 55 ft. from the top, very rare ; 30 ft., very rare. Lagena marginata Walker and Boys, plate VIII. fig. 16 a, b. li Ser pula ( Lagena ) marginata ” Walker and Boys, 1784, Test. Min., p. 2, pi. i. fig. 7. Lagena marginata Brady, 1884, Chall. Rep., vol. ix. p. 476, pi. lix. figs. 21-23. The specimen of Lagena marginata from the Gault is almost precisely similar to the first of the figures given by Dr. Brady in his Report on the c Challenger ’ Foraminifera, save that its keel-like margin is denticulate at the aboral end. This species has been before re- corded from the Phosphate beds of Cambridge, the Upper Chalk of Riigen, and from many other fossiliferous deposits of Eocene, Miocene, Pliocene, and Post-pliocene ages. It occurs in the Gault in zone xi., 12 ft. from the top, very rare. Lagena quinguelatera Brady, var. inflata , plate VIII. fig. 17 a, b. Test elongate, five-sided ; the oval end broad, tapering somewhat gradually below the middle to the inferior end ; the angles formed by Foraminiferci of the Gault of Folkestone. By F. Chapman. 585 5 rounded costae ; aperture ectosolenian, and the aboral extremity minutely denticulate. Length 1/100 in. This variety differs from the species described by Dr. Brady * in having rounded angles to the shell and slightly inflated sides. One specimen only, from zone ii., specimen a. Sub-family N0D0SAB1IN2E. Nodosaria Lamarck [1816]. Sub-genera Glandulina; Dentalina 1 d’Orbigny [1826]. Nodosaria (Gl.) humilis Boemer, plate VIII. fig. 18. Nodosaria humilis Roemer, 1841, Verst, norddeutsch. Kreide, p. 95, pi. xv. fig. 6. Glandulina mutabilis, pars, Beuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. pp. 58, 91, pi. v. figs. 9,11.. This is a somewhat uncommon but very distinct form in the Gault series. Dr. Reuss has grouped the longer forms with Roemer’s species under the name of Gl. mutabilis; but since Gl. humilis exhibits very slight variation from the typical peg-top-shaped form, it seems justifiable to retain the earlier name for the species possessing an ovoid outline. It has been recorded, with the species next to be described, from the Upper Hils-clay, the Speeton Clay, and Gault of North Germany (Roemer, Beuss) ; from the Gault of Folkestone (Reuss, Rupert Jones); from the Gault of France (Berthelin) ; and from the Chalk-detritus of Charing (Rupert Jones in Morris’s Cat.). It is found in the Folkestone Gault in zone v., very rare ; zone x., very rare ; zone xi., 40 ft. from the top, very rare. Nodosaria (Gl.) mutabilis Reuss, plate VIII. figs. 19, 20. Glandulina mutabilis , pars, Reuss, 1862, vol. xlvi. pp. 58, 91, plate v. fig. 7, 8, 10. The forms which are here placed under Reuss’s name of Gl. mutabilis are the very variable, lengthened, and irregular ones of which the two specimens figured are examples. The references to previous occurrences given for Gl. humilis apply also to this form. It is found in the Gault of Folkestone in zone iii., very rare ; zone vi., very rare ; zone xi., 35 feet from the top, very rare ; 20 ft., rare ; 6 ft., very rare. Nodosaria (Gl.) cylindracea Reuss, plate VIII. fig. 21. Nodosaria (Gl.) cylindracea Beuss, 1845, Verstein. d. bohm. Kreideform., pt. i. p. 25, plate xiii. figs. 1, 2. Glandulina cylin- * Lagena quinquelatera Brady, 188], Quart. Journ. Micr. Sci., vol. xxi. N. S. p. 60. Id., 1884, Chall. Rep., vol. ix. p. 454, pi. lxi. figs. 15, 16. 586 Transactions of the Society. dracea Reuss, 1860, Sitzungsb. d. k. Ak. Wiss. Wien, yol. xl. p. 190, plate iv. fig. 1. Nodosaria {Gil.) cylindracea Burrows, Sherborn and Bailey, 1890, Journ. R. Micr. Soc., p. 556, plate ix. fig. 17. N. cylindracea is peculiarly a shorter form in the Gault than from the other localities. It usually has from 2-3 chambers, whilst Reuss’s specimens had from 3-6. This species has also been found in the Red Chalk of Speeton (Burrows, Sherborn and Bailey) ; and in various strata of Cretaceous age in Bohemia, and North Germany (Reuss). It is found in the Folkestone Gault in zone xi., 50 ft. from the top, rare ; 45 ft., rare ; 30 ft., very rare ; 12 ft., frequent. Nodosaria radicula Linne sp., var. Jonesi Reuss, plate VIII. fig. 22. Nodosaria Jonesi Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 89, plate xii. fig. 6. This variety is distinguished by the regular increase in the size of the chambers, and by the first one commencing with a sharp point. The surface of the shell is always extremely polished. It was first described by Reuss from the Folkestone Gault, and this is apparently the only locality where it occurs. It is found in zone ix., very rare ; zone xi., 55 ft. from the top, very rare ; 50 ft., very rare ; 45 ft., common ; 30 ft., very rare ; 12 ft., very rare. Nodosaria oligostegia Reuss, plate VIII. fig. 23. Nodosaria oligostegia Reuss, 1845, Verstein. d. bohm. Kreideform., pt. i. p. 27, plate xiii. figs. 19, 20. N. simplex Silvestri, 1872, Nodos. Foss, e Viv. d’ltal., p. 95, plate xi. figs. 268-272. N. oligo- stegia Burrows, Sherborn and Bailey, 1888, Journ. R. Micr. Soc., p. 384. N. simplex Burrows, Sherborn and Bailey, 1890, Journ. R. Micr. Soc., p. 556, plate ix. fig. 19. This species has been recorded from the Speeton Chalk (Burrows, Sherborn and Bailey) ; the Planermergel of Bohemia (Reuss) ; the Chalk-detritus, Charing (Rupert Jones); the Pliocene of Italy (Silvestri) ; and as a recent form from 129 and 275 fathoms (Brady). It occurs in the Gault in zone vii., very rare ; zone xi., 55 ft. from the top, very rare ; 45 ft., very rare, Nodosaria {ID.) expansa Reuss, plate VIII. fig. 24. Dentalina expansa Reuss, 1860, Sitzungsb. d.k. Ak. Wiss. Wien, vol. xl. p. 188, plate iii. fig. 4. This form is represented by fragments only ; and it was in this condition that Reuss found it, in the Senonian of Westphalia. It occurs in the Gault in zone ii., specimen b, very rare ; zone iii., very rare ; zone xi., 45 ft. from the top, very rare ; 35 ft., very rare. Foraminifera of the Gault of Folkestone. By F. Chapman. 587 Nodosaria ( D .) farcimen Soldani sp., plate VIII. fig. 25. “ Orthoeeras Farcimen ” Soldani, 1791, Testaceographia, vol. i. pt. 2, p. 98, plate cv. fig. O. Nodosaria (D.) laxa Reuss, 1865, Denkschr. d. k. Ak. Wiss. Wien, vol. xxv. p. 132, plate ii. fig. 2, 3. N. (B.) farcimen Brady, 1884, Chall. Rep., vol. ix. p. 499, fig. 13 (woodcut c ). This form, the Gault variety of which is perhaps more nearly represented by Reuss’s figure of B. laxa, is met with in rocks as old as the Permian. Reuss’s specimen was found in the Septaria-clay of Pietzpuhl. It is found in the Gault in fragments only in zone viii., rare ; zone x., frequent ; zone xi., 45 ft. from the top, very rare ; 6 ft., very rare. Nodosaria (B.) soluta Reuss, plate VIII. fig. 26. Bentalina soluta Reuss, 1851, Zeitschr. d. deutsch. geol. Gesellsch., vol. iii. p. 60, plate iii. fig. 4 a, b. B. catenula Reuss, 1860, Sitz- ungsb. d. k. Ak. Wiss. Wien, vol. xl. p. 185, plate iii. fig. 6. B. so- luta Hantken, 1875, Mitth. Jahrb. d. k. ung. geol. Anstalt, vol. iv. p. 29, plate ii. figs. 2, 14. N. (B.) soluta Brady, 1884, Ohall. Rep., vol. ix. p. 503, plate lxii. figs. 13-16. This very distinct form is met with in the Gault in zone i., specimen b, frequent ; zone ii., specimen b, very rare ; zone x., very rare ; zone xi., 50 ft. from the top, common ; 30 ft., very rare ; 25 ft. frequent ; 12 ft., very rare. Nodosaria ( B .) soluta Reuss, var. discrepans Reuss var., plate VIII. fig. 27. Bentalina discrepans Reuss, 1860, Sitzungsb. d. k. Ak. Wis3. Wien, vol. xl. p. 184, plate iii. fig. 7. This variety is distinguished from the type form (V. soluta) by having less constricted sutures and elliptical-shaped chambers. It was described by Reuss from specimens found in the Senonian of Westphalia. One example only from the Folkestone Gault was found in zone viii. Nodosaria (D.) soluta Reuss, var. pulchella, plate VIII. fig. 28. This variety differs from the typical B. soluta in having a more slender and tapering shell ; the commencing segments are spherical and closely conjoined, and in subsequent growth approach the type form in being separated by the sutural constrictions. Length 1 /34 in. It is found in the Gault in zone ix., rare ; zone xi., 40 ft. from the top, very rare. Nodosaria (D.) gracilis d’Orbigny, plate VIII. fig. 29. Bentalina gracilis d’Orbigny, 1840, Mem. Soc. geol. France, vol. iv. p. 14, plate i. fig. 5. 588 Transactions of the Society. The Gault specimens generally possess fewer chambers ; otherwise they correspond with the figure given by d’Orbigny, of the specimens from the White Chalk of France. This form has been previously recorded from the Gault of Folkestone and the Chalk-detritus of Charing, &c. (Rupert Jones) ; and also from the Bohemian Chalk (Iieuss). In the Gault it is found in zone ii., specimen a , very rare ; zone iii., very rare ; zone iv., rare ; zone vi., rare ; zone ix., very rare ; zone x., very rare ; zone xi., 50 ft. from the top, very rare ; 45 ft. rare ; 6 ft., very rare. Nodosaria (D.) Lorneiana d’Orbigny, plate VIII. figs. 30, 31. Dentalina Lorneiana d’Orbigny, 1840, Mem. Soc. geol. France, vol. iv. p. 14, plate i. figs. 8, 9. Nodosaria Lorneiana Reuss, 1845, Verstein. bohm. Kreideform., vol. i. p. 27, plate viii. fig. 5. This variety has long and somewhat elliptical chambers, with the sutural lines strongly marked. Two specimens from the Gault are figured, one of which (imperfect) is quite straight, and the other curved ; the two specimens may serve to illustrate the fact that both the Nodosarine and the Dentaline modes of growth may be seen in what are evidently the same species. It has also been recorded from the Chalk of Kent, and the Lower Chalk of Dover (Rupert Jones) ; and from the Bohemian Chalk (Reuss). Found in zone iii., very rare ; zone xi., 50 ft. from the top, very rare ; 45 ft., very rare ; 25 ft., very rare. Nodosaria (D.) pauperata d’Orbigny, plate VIII. fig. 32. Dentalina pauperata d’Orbigny, 1846, For. Foss. Vien., p. 46, plate i. figs. 57, 58. D. pauperata Bornemann, 1855, Zeitschr. d. deutsch. geol. Gesellsch., vol. vii. p. 324, plate xiii. fig. 7. D. paupe- rata Brady, 1884, Chall. Rep., vol. ix. p. 500, woodcuts fig. 14 a, b , c. D. pauperata Sherborn and Chapman, 1886, Journ. R. Micr. Soc., p. 750, pi. xv. fig. 9. This species is present in most microzoic strata from the Lias to Recent. In the Folkestone Gault it is found in zone iii., rare ; zone iv., very rare ; zone vii., rare ; zone xi., 55 ft. from the top, very rare ; 45 ft., frequent ; 25 ft., rare ; 12 ft., very rare. Nodosaria (D.) consobrina d’Orbigny, plate VIII. fig. 33. Dentalina consobrina d’Orbigny, 1846, For. Foss. Vien., p. 46, pi. ii. fig. 1-3. N. ( D .) consobrina Brady, 1884, Chall. Rep., vol. ix. p. 501, pi. lxii. figs. 23, 24. This cosmopolitan species is well distributed in the Gault. It is found in zone iii., very rare; zone v., very rare; zone viii., rare; zone xi., 50 ft. from the top, frequent ; 40 ft., very rare ; 35 ft., rare ; 30 ft., very rare ; 25 ft., frequent ; 12 ft., very rare. Foraminifera of the Gault of Folkestone. By F. Chapman. 589 Nodosaria ( D .) cylindroides Keuss, plate VIII. fig. 34. Bentalina cylindroides Reuss, 1860, Sitzungsb. d. k. Ak. Wiss. Wien, yoI. xl. p. 185, pi. i. fig. 8. B. cylindroides Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 41, pi. ii. fig. 16. This form has been recorded from the Gault and Chalk of North Germany (Reuss) ; and from the French Gault (Berthelin). In the Gault of Folkstone it is found in zone v., very rare ; zone x., very rare ; zone xi., 45 ft. from the top, rare ; 20 ft., very rare. Nodosaria (B.) hamulifera Reuss, plate VIII. fig. 35. N. (D.) hamulifera Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 42, pi. ii. fig. 17. The figure given by Reuss under the above name agrees exactly with the specimen found in the Gault, except that the latter has three chambers instead of four. Its distinguishing character, how- ever, of a commencing hooked process is of value most probably only in separating local varieties of the N. communis type. Previously recorded from the Upper Hils-clay of Germany (Reuss). In the Gault it is found in zone xi., 25 ft. from the top, one specimen. N. (D.) xiphioides Reuss, plate VIII. fig. 36. N. (D.) xiphioides Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 43, pi. iii. fig. 1. The specimen originally figured by Reuss possessed seven to eight chambers, whilst the Gault specimen has only four. There is no doubt, however, that this is the same species, as it possesses the distinct characters of a spike at the commencement placed eccen- trically, and has the chambers separated by deeply marked sutural lines. Previously found in the Mimimus-cl&j of North Germany (Reuss) ; and in the French Gault (Berthelin). In the Folkestone Gault it is found in zone v., very rare. Nodosaria (D.) legumen Reuss, plate VIII. fig. 37. Nodosaria (B.) legumen Reuss, 1845, Verstein. bohm. Kreide- form., pt. i. p. 28, plate xiii. figs. 23, 24. N. legumen Reuss, 1860, Sitzungsb. d. k. Ak. Wiss. Wien, p. 187, plate iii. fig 5. This is a well-defined and widely distributed form in the Gault. It has been found in various strata of the Chalk series in Bohemia, Galicia, and Hanover ; in the Gault of the Rhine (Reuss) ; in the Gault of Folkestone (Rupert Jones) ; and in the Gault of Montcley (Berthelin). In the Folkestone Gault it is found in zone vii., very rare ; zone xi., 50 ft. from the top, frequent ; 40 ft., rare ; 35 ft., rare. Nodosaria (D.) Roemeri Neugeboren, plate VIII. fig. 38. Bentalina Roemeri Neugeboren, 1856, Denkschr. d. k. Ak. Wiss. Wien, vol. xii. p. 82, plate ii. figs. 13-17. D. nana Reuss, 1862, 590 Transactions of the Society. Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 39, plate ii. figs. 10, 18. B. nana Bertbelin, 1880, Mem. Soc. geol. France, ser. 3, vol. i. mem. 5, p. 43. This species has been found in the North-German Gault (Reuss) ; the Gault of Montcley, France (Berthelin) ; the Septaria-clay of Germany (Keuss, Schlicht) ; and the Miocene of Transylvania (Neuge- boren). As a recent form it affects depths down to 400 fathoms (Brady). It is found in the Gault of Folkestone in zone i., specimen h, very rare ; zone iv., very rare ; zone vii., very rare ; zone x., frequent ; zone xi., 55 ft. from the top, frequent ; 45 ft., very rare ; 35 ft., frequent ; 30 ft., frequent ; 25 ft., frequent ; 20 ft., very rare ; 12 ft., frequent ; 6 ft., very rare. Nodosaria (B.) communis d’Orbigny, plate IX. fig. 1. Nodosaria (B.) communis d’Orbigny, 1826, Ann. Sci. Nat., vol. vii. p. 254, No. 35. B. communis d’Orbigny, 1840, Mem. Soc. geol. France, vol. iv. p. 13, plate i. fig. 4. N. ( B .) communis Reuss, 1845, Yerstein. bohm. Kreideform., pt. 1, p. 28, plate xii. fig. 21. The typical B. communis is found in various Cretaceous deposits newer than the Gault, such as the Planermergel of Bohemia (Reuss) ; besides all important deposits above and below the Cretaceous series. In the Folkestone Gault it occurs in zone iii., very rare ; zone v., rare ; zone vii. frequent ; zone ix., frequent ; zone xi., 55 feet from the top, common; 50 ft. common; 45 ft., rare; 40 ft., frequent; 35 ft., common; 30 ft., frequent; 25 ft., very common; 12 ft., frequent. Nodosaria (D.) mucronata Neugeboren, plate IX. fig. 2. Bentalina mucronata Neugeboren, 1856, Denkschr. d. k. Ak. Wiss. Wien, vol. xii. p. 83, plate iii. figs. 8-11. N. ( B .) mucronata Brady, 1884, Chall. Rep., vol. ix. p. 506, plate Ixii. figs. 27-29. N. (B.) mucronata Burrows, Sherborn and Bailey, 1890, Journ. R. Micr. Soc., p. 557, plate ix. fig. 31. This species has been found in the Speeton Chalk (Burrows, Sherborn and Bailey) ; and in various beds of Tertiary age. As a recent form it is unrestricted as to depth. In the Gault it is found in zone v., very rare ; zone x., very rare ; zone xi., 30 ft. from the top, very rare ; 25 ft., very rare ; 12 ft., very rare. Nodosaria (D.) costellata Reuss, plate IX. fig. 3. Nodosaria costellata Reuss, 1845, Yerstein. bohm. Kreideform., pt. 1, p. 27, plate xiii. fig. 18. This form was found by Reuss in the Planermergel of Bohemia. The lower part of Reuss’ shell was ornamented with striae extending half-way across the chambers, whilst the upper part was wholly striate. A fragment only was found in zone xi., 45 ft. from the top. Foraminifera of the Gault of Folkestone. By F. Chapman. 591 Nodosaria (D.) raristriata, plate IX, fig. 4. Shell filiform, consisting of ten or more segments, tapering to the commencement with a sharp point. The surface of the test decorated on each aspect with three or four somewhat interrupted and fine costae. Length 1/26 in. This elegant but rare form is found (usually frag- mentary) in zone xi., 55 ft. from the top, rare ; 45 ft., rare ; 40 ft. very rare ; 30 ft., very rare ; 6 ft., very rare. Nodosaria hispida d’Orbigny, plate IX. fig. 5. Nodosaria hispida d’Orbigny, 1846, For. Fos. Vien., p. 35, plate i. figs. 24, 25. N. hispida Brady, 1884, Chall. Rep., vol. ix. p. 507, plate lxiii. figs. 12-16. The specimens found in the Gault are in a fragmentary condition, and with the superficial processes evidently worn down close to the surface of the shell. This species has been recorded from the Lias of England (Brady, Walford) ; the Chalk of Ireland (Wright) ; the Phosphatic Chalk of Taplow (Chapman) ; and from numerous beds in the Tertiary and Post- tertiary formations. It occurs in zone i., specimen b , frequent ; zone iv., common ; zone v., frequent ; zone vii., frequent ; zone xi., 45 ft. from the top, frequent. Nodosaria perpusilla, plate IX. fig. 6. Shell slightly tapering to the commencement, cylindrical, and consisting of a straight series of about seven chambers, the breadth of each chamber nearly equal to the length ; the sutures distinctly marked ; the aboral end mucronate. Surface of the shell ornamented with from six to seven delicate longitudinal costae. Length 1/70 in. This form is the smallest of the Gault Nodosariae. It is found in zone iii., rare ; zone v., very rare ; zone xi., 50 ft. from the top, very rare. Nodosaria bambusa, plate IX. fig. 7. Shell consisting of subcylindrical, or slightly inflated, segments, four times longer than their breadth ; the divisions between the chambers seen only as translucent sub-surface markings. The surface of the test decorated with fine and numerous longitudinal costae, which are slightly diverted or twisted towards one side. Found in fragments only. Average length of chambers 1/33 in. This elegant species occurs in the Gault in zone v., rare; zone xi., 55 ft. from the top, very rare. Nodosaria (D.) inter cellular is Brady, plate IX. fig. 8. Nodosaria intercellularis Brady, 1881, Quart. Journ. Micr. Sci., vol. xxi. N.S., p. 63. N. (D.) intercellularis Brady, 1884, Chall. Rep., vol. ix. p. 515, plate lxv. figs. 1-4. 592 Transactions of the Society. The Gault specimens agree very closely with the figures given by Dr. Brady. Regarding the peculiar shell-structure shown in Dr. Brady’s Report, p. 516, fig. 15 a, b, it has been impossible to give sufficient material for a drawing, from the Gault specimens, owing to their rarity ; from a shell mounted in Canada balsam, however, some evidence has been obtained, which supports the idea of the existence of the same structure as is seen in the recent specimens. Dr. Brady’s specimens were obtained from one locality only, off Bermuda, at a depth of 435 fathoms. It is found in the Gault in zone iii., very rare ; zone xi., 25 ft. from the top, rare. Nodosaria sceptrum Reuss, plate IX. fig. 9. Nodosaria sceptrum Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 37, plate ii. fig. 3. This species was figured by Reuss from specimens obtained from the Upper Hils formation of North Germany. This form has appeared in one instance only in the Folkestone Gault, near the base of the beds ; and it is interesting to note that, while Reuss’s specimens are large and fully developed, and have come from beds older than the Gault, the specimen from the latter formation is small and ill- developed. It occurs in the Gault in zone i., specimen b, one specimen.* Nodosaria internotata , plate IX. fig. 10. Shell consisting of five more or less inflated chambers, the last much larger than the others. The surface ornamented with delicate costae, between which are secondary costulae consisting of much inter- rupted lines and dots. Length 1 /48 to 1 /30 in. Found in zone i., specimen b, very rare ; zone iii., very rare ; zone v., very rare ; zone xi., 50 ft. from the top, very rare ; 45 ft., rare ; 35 ft., very rare ; 30 ft., very rare. Nodosaria ( D .) tubifera Reuss, plate IX. fig. 11. Nodosaria tubifera Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 37, plate ii. fig. 4. This form was figured by Reuss from specimens obtained from the Hils formation of North Germany. The Folkestone specimens are sometimes slightly curved in the line of growth ; and the specimen figured shows a larger number of costae than is usually seen, though the form of the shell is very typical. It is found in zone i., specimen b, frequent ; zone iii., frequent ; zone iv., very rare ; zone v., very rare; zone vi., rare; zone viii., very rare; zone xi., 55 ft. from the top, rare ; 50 ft., very rare ; 45 ft., frequent ; 40 ft., frequent ; 35 ft., frequent ; 20 ft., very rare. * This specimen was unfortunately destroyed after the drawing was made. Foraminifera of the Gault of Folkestone . By F. Chapman . 593 Nodosaria (D.) Zippei Reuss, plate IX. fig. 12. Nodosaria Zippei Reuss, 1845, Verstein. bdhm. Kreideform., pt. i. p. 25, plate viii. figs. 1-3. N. Zippei Rupert Jones, 1854, Lecture on the Geological History of Newbury, pi. ii. fig. 1. This characteristic Cretaceous form has been recorded from various horizons in the Chalk of Bohemia (Reuss) ; and from the Chalk of England (Rupert Jones), and of the North of Ireland (Wright). Many of the Gault specimens are distinctly curved in the line of growth. It is found in zone v., very rare ; zone vii., very rare ; zone ix., very rare ; zone x., very rare ; zone xi., 55 ft. from the top, common; 50 ft., rare; 45 ft., rare; 35 ft., frequent; 30 ft. very rare; 25 ft., very rare; 20 ft., very rare ; 12 ft., very rare; 6 ft., very rare. Nodosaria ( D .) paupereula Reuss, plate IX. figs. 13, 14. Nodosaria paupercula Reuss, 1845, Yerstein. bohm. Kreideform., pt. i. p. 26, pi. xii. fig. 12. JDentalina paupereula Berthelin, 1880, Mem. Soc. geol. France, ser. 3,vol. i., No. 5, p. 43, pi. ii. fig. 17 a , b . This somewhat variable species is well distributed in the Gault. It is also found in the Chalk of Bohemia (Reuss) ; and the Gault of France (Berthelin). At Folkestone it is found in zone i., specimen b, very rare ; zone ii., specimen b , very rare ; zone iii., rare ; zone iv., common ; zone v., common ; zone vii., frequent ; zone ix., frequent ; zone xi., 12 ft., from the top, frequent ; 6 ft., very rare. Nodosaria (Z>.) Fontannesi Berthelin, plate IX. fig. 15. Dentalina Fontannesi Berthelin, 1880, Mem. Soc. geol. France, ser. 3, vol. i. No. 5, p. 42, plate ii. fig. 14. This form, which has been described from the French Gault, is found at Folkestone in zone ii., specimen a, rare ; zone iii., frequent ; zone iv., rare ; zone v., very rare ; zone vi., rare ; zone ix., very common ; zone x., very common ; zone xi., 55 ft. from the top, very rare; 50ft., frequent ; 35 ft., frequent; 12 ft., frequent. Nodosaria ( D .) obscura Reuss, plate IX. fig. 16. Nodosaria obscura Reuss, 1845, Yerstein. bohm. Kreideform., pt. i. p. 26, plate xiii., figs. 7, 8, 9. N. obscura Burrows, Sherborn and Bailey, 1890, Journ. Roy. Micr. Soc., p. 557, plate ix. fig. 24. The above name can be conveniently applied to those strongly costate forms of Nodosaria, in which the septation is imperfectly defined on the surface of the shell. This species has been previously recorded from the Gault of Folkestone and the Upper Greensand of Warminster (Rupert Jones) ; the French Gault (Berthelin) ; the Red Chalk of Speeton (Burrows, Sherborn and Bailey) ; from the Greensand of the Gault of the Rhine, and in various Cretaceous strata 594 Transactions of the Society. from the Lower to the Upper Chalk in England and Bohemia (Reuss). It is found in the Folkestone Gault in zone i., specimen b, frequent ; zone ii., specimen b, very rare; zone iii., rare; zone vi., very rare; zone vii., very rare ; zone viii., frequent; zone ix., very rare; zone x., very common ; zone xi., 55 ft. from the top, common ; 50 ft., rare ; 45 ft., rare ; 40 ft., rare ; 35 ft., very rare ; 30 ft., frequent ; 25 ft., frequent ; 20 ft., rare. Nodosaria inflata Reuss, plate IX. figs. 17, 18. Nodosaria inflata Reuss, 1845, Yerstein. bohm. Kreideform., pt. i. p. 25, plate xiii. figs. 3, 4. The name of N. inflata may he applied to those somewhat aberrant forms which have the commencement of the test with or without constrictions, but with the later growth more or less inflated. Reuss described this species from the Planermergel of Luschitz, Bohemia. It is found in the Gault in zone v., very rare ; zone ix., rare ; zone xi., 55 ft. from the top, very rare ; 25 ft., rare ; 12 ft., very rare. Nodosaria tenuicosta Reuss, plate IX. figs. 19, 20. Nodosaria tenuicosta Reuss, 1845, Yerstein. bohm. Kreideform., pt. i. p. 25, plate xiii. figs. 5, 6. N. lamellosocostata Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi., p. 38, plate ii. fig. 16. N. tenuicosta Berthelin, 1880, Mem. Soc. geol. France, ser. 3, vol. i. No. 5, p. 32, plate i. fig. 18 a , b. This form was originally described from specimens out of the Planermergel of Bohemia (Reuss ; also found in the Gault of Montcley (Berthelin). The smaller specimen here figured closely approaches the form described by Reuss under the name of N. lameb losocostata, but which I have included with N. tenuicosta , as there is enough evidence in a large series of specimens to show that it is quite unnecessary to separate them. N. lamellosocostata has been found in the Upper Hils formation, the Speeton Clay, and the Minimus- thon of North Germany (Reuss) ; and the Gault of Folkestone (Reuss, Rupert Jones). In the Gault of Folkestone it is found in zone i., specimen b, frequent; zone iii., rare; zone vi., frequent; zone vii., rare ; zone viii., frequent ; zone ix., frequent ; zone x., common ; zone xi., 50 ft. from the top, frequent ; 45 ft., frequent ; 40 ft., very rare ; 35 ft., rare ; 30 ft., rare ; 25 ft., very rare ; 20 ft., very rare ; 12 ft., common. Nodosaria prismatica Reuss, plate IX. fig. 21. Nodosaria prismatica Reuss, 1860, Sitzungsb. d. k. Ak. Wis\ Wien, vol. xl., p. 180, plate ii. fig. 2. N. prismatica Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 36, plate ii. fig. 7. Foraminifera of the Gault of Folkestone . By F. Chapman. 595 N. prismatica Burrows, Sherborn and Bailey, 1890, Journ. Roy. Micr. Soc., p. 557, plate ix. fig. 25 a, h. This fossil has been recorded from various beds in the Gault and the Speeton Clay of North Germany (Reuss) ; from the French Gault (Berthelin) ; and from the Red Chalk of Speeton (Burrows, Sherborn and Bailey). In the Folkestone Gault it is found in zone i., speci- men b, rare ; zone ii., specimen b, rare ; zone ii., specimen c, very rare ; zone iii., common ; zone iv., rare ; zone v., common ; zone vi., very rare ; zone vii., very rare ; zone x., frequent ; zone xi., 55 ft. from the top, frequent ; 45 ft., rare ; 35 ft., very rare ; 20 ft., very rare ; 12 ft., frequent ; 6 ft., very rare. Nodosaria orthopleura Reuss, plate IX. figs. 22, 23. Nodosaria orthopleura Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 89, plate xii. fig. 5. This is a very typical species from the Gault. It was originally described by Reuss from Folkestone, and appears to be restricted to that locality. It can be easily distinguished from N. prismatica by its thinner costae, and perfectly straight edges. The number of the costae is generally five, but sometimes six. It occurs in zone ii., specimen b, very rare ; zone iii., very rare ; zone iv., very rare ; zone v., common ; zone vi., very rare ; zone vii., frequent ; zone viii., common ; zone ix., frequent ; zone x., very common ; zone xi., 55 ft. from the top, frequent ; 50 ft., common ; 45 ft., frequent ; 40 ft., frequent ; 35 ft., common ; 30 ft., common ; 25 ft., common ; 20 ft., frequent ; 12 ft., rare ; 6 ft., common. Nodosaria tetragona Reuss, plate IX. fig. 24. Nodosaria tetragona Reuss, 1860, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xl. p. 181, plate ii. fig. 1. The specimen originally described was obtained by Reuss from the greensand in the Gault of the Rhine. It is perhaps only a four- ribbed variety of the more constant form N. orthopleura , as examples are sometimes seen having a tendency to become five-ribbed like the latter species. It occurs in zone iv., very rare ; zone vii., very rare ; zone x., rare ; zone xi., 35 feet from the top, very rare ; 12 ft., very rare ; 6 ft., rare. Frratum. — In Part III. of this paper, 1892, p. 750, line 12 from the bottom, for annectens read complanata. 1893. 2 T 596 Transactions of the Society. XII. On the Development of the Continental Form of Microscope Stand. By J. B. Nias, M.D. {Read 21 st June , 1893.) In spite of unfavourable criticism from many quarters, the Conti- nental pattern of stand is coming into general use in this country, as the proportion of professional workers with the Microscope increases ; and it is worth while to inquire into the grounds of such a preference, because there must exist a good reason for it ; and moreover, in pro- portion as we recede from the date of an invention, details about its origin come to possess a historic interest, and are worth putting on record. I find that this particular chapter in the history of the Microscope has been very briefly treated by every writer, and yet there should be many better able than myself to add to our knowledge on the subject, and only in their absence do I venture on the task. Even if I should not entirely succeed in it, I may render the service of directing atten- tion to sources of information out of the ordinary path. The first point of interest to note about the Continental stand is that it has maintained its form without substantial alteration for nearly fifty years — a proof, in general, that a design has been at the outset the creation of a practical man ; and yet this stand presents several features which are open to criticism, and are in fact un- favourably criticized if taken as representing an optician’s idea of what is suitable for a Microscope; so that it became necessary to investigate the reasons for the steady preference shown for this stand on the Continent, in spite of such defects; and it soon appeared to me that they could only be explained as limitations introduced into the design at the bidding of some particular worker, such restrictions being submitted to by the optician, so that the stand may be regarded as one in which certain features desirable from the purely optical point of view have been deliberately suppressed in order that other advantages may be gained. And as the partisans of this stand are chiefly found among the ranks of anatomists, it seemed reasonable to look for the original designer among them also, the result being that I have arrived at conclusions that appear novel and interesting, and worth communicating to others. The Parisian optician Oberhaeuser is generally named as the inventor of this stand, but, as I have said, it is not easy to understand how an optician by himself could have arrived at a model so defective from the optician’s point of view, and differing so widely from the other types of Microscope in use at the time. Let us, however, suppose him to have worked under directions, and the matter becomes easy of explanation. Accordingly, upon investigation I meet with Development of the Continental Stand . By Dr. J. B. Nias. 597 repeated assertions, never effectively denied, on the part of a certain anatomist, that it was he who designed the original model of the Continental stand for his own particular use, and that it was made for him by the firm to which Oberhaeuser belonged, and finally, that with his sanction it was patented by them, so as to give them for a certain period a monopoly of the manufacture — a fact which well explains its association with their names. 1 also find that this firm were permitted by the anatomist Dujardin to do the same thing with an achromatic condenser which he had invented, and, indeed, that they were actually the first opticians in France who conceived the idea of patenting inventions in connection with the Microscope ; but to substantiate this position requires the enumeration of a considerable number of details. The anatomist to whom I have referred, Strauss-Durckheim by name, pupil of Cuvier, first addressed the scientific public with a work on the anatomy of the Coleoptera, in which the common cockchafer served as a type, which work being beautifully illustrated from his own dissections, aroused some curiosity, as he tells us subsequently, on the part of naturalists as to the methods of investigation employed. To gratify this he undertook a second treatise on the methods of com- parative anatomy, in which, among other instruments, are figured two Microscopes which appear to me to present the earliest type, regard being had to dates, of the Continental stand. The work of dissecting small animals requiring the alternate use of the simple and the compound Microscope with as little disturbance as possible of the preparation, together with its arrangement in a convenient form for manipulation, we find this point particularly studied in the design of these two stands : firstly, by the introduction of a rotating stage ; secondly, by a limited height and a vertical position of the model. A precise account of his claims to this invention is to be found in a letter written by Strauss-Durckheim in 1850 to the optician Chevalier, which is printed in the life of the latter by his son ; from it I quote the following paragraphs : — “ Having formerly had to occupy myself a good deal with anatomical researches on very small animals with a Microscope, which by a kind of chance, was of small dimensions, I did as other microscopists do, I tried to make the best of it by perfecting the mechanical part by several means which necessity suggested to me, and reflecting on all the inconveniences which I had encountered in my microscopical re- searches during my long experience, I finished by designing one of these instruments in which all difficulties were removed, and this was the Microscope of which I published the description in my work on the art of dissecting which I mentioned above ” (the Treatise on Comparative Anatomy published in 1842, this being written in 1850). He continues, “ The first requisite of the Microscope is to have in all about 3 dm. (=12 inches) in height, so that the observer, comfortably seated at the table at which he is working, and on which the Micro- 2 t 2 598 Transactions of the Society. scope is placed, may have his hands on the stage of the latter where the object is which he is examining, whilst he looks into the eye- piece to see what he is doing while dissecting this object; which amounts to saying that the proportions which have appeared to me most suitable are those where the stage is raised about a decimetre (4 in.) above the table, and the entire tube of the Microscope is only about 2 dm. (8 in.) long or a little more. The difficulty of arranging and suitably fixing the object which one examines being equally one of the greatest inconveniences in this kind of research, especially in the case of very small objects which a displacement of 1/10 mm. will cause to travel out of the field of the Microscope, and which one ordinarily thus loses without being able to find them again, this inconvenience requires that such objects should be capable of being turned on themselves in every direction without displacing them from their situation in order to attack them from all sides. This advantage I have obtained by simply making the stage of the Microscope movable on its centre. By this means, without touching the object itself, whether it be fixed or not, one can place it in all desired positions, and that without its receiving the slightest shock which might displace it. The observer requiring to have his hands firmly resting on this same stage while dissecting the object which he is studying, I have also found that the most suitable width for such a stage is that where it has about 1 dm. (4 in.) in breadth.” He goes on to state the requirements of such a Microscope in a similar way at some length, but enough has been quoted to suggest that we meet here for the first time with a precise definition of what have become the standard dimensions of the Continental Microscope stand. Up to 1835, which appears to have been about the date of the introduction of this model, there was no uniformity in the design of Microscope stands, and it appears to me that this pattern succeeded in ousting all others by conforming in some degree, as described above, to the proportions of the human body, much as a spectacle frame is adapted to the face. One may be sure that for continuous and laborious use, such as falls to the lot of a professional worker, such an instrument as is least productive of muscular fatigue will be most fruitful in results. For it is evident that a man sitting at a table in the attitude of work will have his eyes naturally situated about 14 in. above the table, and about 6 in. from its edge, so that his arms, as they rest on the table before him, will bring his hands close together in front, the direction of his eyes falling upon them without con- straint, at an angle of about 15° from the vertical. A stand which falls into place within these dimensions will save fatigue — an advan- tage for which much may be sacrificed in many kinds of work. With a weighted foot, if produced slightly backwards, sufficient stability may be gained for such a small degree of inclination, or the vertical position will not be found extremely irksome, at least to the pro- Development of the Continental Stand. By Dr. J. B. Nias. 599 fessional worker. The breadth of the hand regulates the height of the stage and its breadth ; and the remainder of the space between the eyes and the table is all that is available for the length of the tube. Whatever opticians may say, those who have to economize labour will be found generally to prefer such a type of instrument ; and the question arises whether it is more probable that such a design should have originated in the mind of an optician, or in that of a user of the Microscope. I incline to the latter opinion, and may interpose the query whether any other reason can be given for fixing the tube- length for which Continental objectives are corrected at 150 mm. or thereabouts.* In fig. 89 the first of the two instruments described by Strauss- Durckheim is represented in outline. It is merely a dissecting Microscope of common type with the important addition that the stage, which is carried by a movable bracket, is made to rotate, and is provided at its edge with several sockets, of which three are shown, for what we now term stage forceps, by which the various parts of the object under dissection are drawn asunder and fixed, while by rotation of the stage the preparation is turned into convenient positions for dissection. 1 do not find the right of Strauss-Durckheim to be regarded as the inventor of this rotating type of stage anywhere disputed, and in the letter to Chevalier quote! the writer makes the explicit statement that the first Microscope of the kind was constructed for him by the optician Cauchoix before 1824, four years before the publication of his work on the Coleoptera.t In fig. 90, the compound Microscope is represented, and as being much more novel in form, it deserves a detailed examination. The foot is round and weighted with lead, and carries a cylinder or drum of brass with an aperture at one side for the admission of light to the mirror, which, swung between pivots of which the ends project through the sides of the drum, is focused vertically by a rack and pinion of which the milled head is seen behind. At the top of the drum is a slit which gives passage to the edge of a circular diaphragm, and the stage, like that of the simple Microscope, is round and fitted in the * The following are the authorities for the foregoing statements : — (a) H. Strauss- Durckheim, ‘Traite d’anatomie comparative,’ Paris, 1842, pp. iii. and 74-90. ( b ) A. Chevalier, ‘ Vie de Charles Chevalier,’ Paris, 1862, pp. 120 et seq. (c) ‘ Comptes rendus de l’Academie des Sciences,’ xx. pp. 574, 892. (d) Dujardin, art. Microscope in ‘ Dictionnaire de l’industrie manufacturiere par A. Baudrimont,’ Paris, 1838. (e) Charles Chevalier, ‘ Notes rectificatives pour servir a l’histoire des Microscopes,’ Paris, 1835, pp. 10, 19, for a sight of which rare pamphlet I am indebted to the courtesy of Mr. Frank Crisp, F.R.M.S. (/) Patents to be seen in our Patent Office Library, Trecuurt and Oberhaeuser, French Patents, series i. vol. xlviii., No. 5469, Aug. 17, 1837 ; G. Oberhaeuser, series ii. vol. xvii. p. 81, July 16, 1849. t See a statement to this effect in Ch. Robin’s ‘ Traite du Microscope,’ where the rotating stage is expressly attributed to Strauss-Durckheim. 2nd ed., Paris, 1877,. p. 54. Fig. 89. 600 Transactions of the Society. same way for numerous stage forceps ; but, inasmuch as its rotation with these in place would bring their projecting ends against the pillar of the Microscope, the direct connection of the latter with the foot is severed, and it is inserted instead on a projecting lip of the stage upon which it is centered by being fitted loosely in a hole, where it is clamped in concentricity with the diaphragm by the clamping screw seen underneath. It is expressly admitted by Strauss-Durck- heim that the working out of this feature was effected by M. Trecourt, Oberhaeuser’s senior partner ; and here we may ask for the original source of such a model. The inventor having stated that he originally worked “ with a Microscope which, by a kind of chance, was of small dimensions,” there was only one pattern extant at the time, which corresponds to this description and could have served as a basis for the design. This is the so-called drum Microscope, shown in fig. 91, which is now only used for toys, but was Fig. 90. Fig. 91. a(j0pted by the optician Fraunhofer, of Munich, as a regular pattern about 1815, and was certainly manufactured in Paris by Chevalier, Lerehours, Trecourt, and per- haps others from 1830 onwards; and it is not difficult to see how the combination of this stand with a rotating stage would result in the design of fig. 90.* Returning to this instrument it will be noticed that the pillar which carries the body is enveloped in two outer tubes or sleeves, the inner of which, by means of a micrometer screw and spring, slides up and down to afford the now familiar form of fine-adjustment, whose milled head is seen below the clamping screw which its stem perforates ; while the outer is intended to allow the body to be swung to one side through an angle of 90°, when a simple lens mounted on another stand is to be brought over the dissection — a necessity only likely to be foreseen by an anatomist. The tube of the Microscope itself is so evidently adapted from fig. 91 as to need no observation, and the only novelty is that it is double within, so as to permit of the use of a second objective above the first, as an erector, an original feature for which Strauss-Durckheim can also claim priority.! * An exact apportionment of the credit between the joint inventors is difficult to make after this lapse of time, and beyond the main purpose of this paper. Chevalier in the pamphlet quoted (‘ Notes Eectificatives, &c.’), tells us that Trecourt and Oberhaeuser on beginning the manufacture of Microscopes about 1830, employed this stand of Fraunhofer's exclusively, which had the advantage over all others in cheapness. The remainder of this pamphlet is occupied with a controversy about priority in the matter of achromatizing objectives, with which we have nothing to do, on the present occasion. t On this point, and Trecourt and Oberhaeuser’s subsequent introduction of such a feature in a Microscope of their own, see Strauss-Durckheim’s ‘TraiteV fpagg. cit. also Comptes Rendus, ix. p. 322, sitting of the Academie des Sciences, Sept. 2, 1839. Development of the Continental Stand. By Dr. J. B. Nias. 601 In fig. 92 is represented the stand as patented by Trecourt and Oberbaeuser, after a cut in Dujardin’s article (loc. cit.) and the drawings of the patent ; specimens of the manufacture, however, which I have seen correspond more closely to the design of fig. 90. Certain features which suggest themselves more particularly to the anatomist as indis- pensable, have been suppressed, such as the outer tube for swinging the body to one side, and the numerous sockets for stage forceps ; and the rotating diaphragm has been replaced by a tube moving vertically through the opening in the stage, hv the aid of a lever at the side, so as to take from above the achromatic condenser of Dujardin patented at the same time, or a set of cylindrical diaphragms, a feature to which Strauss- Durckheim expressly objected as necessitating the disturbance of the preparation on the stage. A rack-and-pinion coarse-adjustment has been added, and the milled head of the fine-adjustment removed to the top of the pillar. This instrument came into great favour, much i ^ aided by its cheapness, and the goodness of the objectives ; and was exhibited at the sitting of the Academie des Sciences on February 13, 1837.* On the occasion of Nachet exhibiting to the Academie des Sciences an apparatus for oblique illumination by means of a prism on June 14, 1847, ten years later, Oberhaeuser, now in business by himself, announces to that body that he has modified his stand so as to admit of the use of the mirror for that purpose, the idea having been sug- gested to him from England by a Mr. Abraham, of Liverpool, and a patent was taken out for this improvement also, though not till two years later.t Fig. 93 represents this second stand, which has now arrived at its modern form. The sides of the drum have been cut away so as to leave a flat pillar, and the round foot has been modified, to correspond, into a horseshoe form. The mirror, borne by a swinging arm, is adjustable vertically by means of a clamping screw. The stage rotates, as before, with the body, but is now made square, and the diaphragms and condenser are carried by a sliding substage. A hinge for inclining is the only subsequent addition to this model ; and the smaller stands with which we are more familiar in this country in the hands of students, are derived from, and posterior to the invention of this larger one, which continues to be made by every Continental optician at a price of 10 1. or 1 51. In fig. 94 I have added, for contrast, the type of Microscope current * Comptus Rendus, iv. p. 250. f French Patents (in our Patent Office Library), series ii., vol. xvii. p. 81, dated July 16, 1849, for a term of 15 years. See Comptes Rendus, xxiv. p. 1052. 602 Transactions of the Society. at the time of the introduction of the Oherhaeuser stand ; it is that made by Chevalier for Dujardin, and with which he worked, the drawing being taken from the article already cited. Like others of the period, it is fixed for use by screwing into the lid of its cabinet, and the focusing is effected by movement of the stage. In the present specimen the compound body can be lifted off the pillar, to be replaced by the arm carrying a simple lens shown in the margin, and by means of a hinge and the interposition of a right-angled prism above the objective, it can be used in the horizontal position. It is, in fact, a simplified form of the “ Microscope Universel” of Chevalier. Stands of similar form were made by Plossl and others at the time, and were equally superseded by the new pattern. Fig. 93. Fig. 94. TT33 [In the original paper, as read, some comparisons followed between the Continental and English forms of stand, which unfortunately were taken as representing me as the advocate of the former exclusively. This was not my intention, and with the approval of Professor Bell, I omit these remarks. With the various observations of the speakers in the discussion I entirely agreed. This matter suggested itself to me originally in the form of two questions to which I found no answer ready : First, why is the tube- length of the Continental stand 150-160 mm. ; why should objec- tives be corrected for this length and no other; and who first decided upon it ? Secondly, why is the Continental Microscope-stand in its complete form provided with a rotating stage of peculiar pattern, the significance of which is not at once apparent ? I investigated the matter historically, with the result presented in the text.] 603 SUMMARY OF CURRENT RESEARCHES RELATING TO ZOOLOGY AND BOTANY (principally Invertebrata and Cryptogamia ), MICROSCOPY, &c., INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS ANI) OTHERS* * * § ZOOLOGY. A. VERTEBRATA: — Embryology, Histology, and General. a. Embryology, f Vitelline Body of Balbiani in Egg of Vertebrates.:}: — M. L. F. Henneguy finds that the vitelline nucleus or so-called vitelline body of Balbiani is a constituent of the egg which may be observed in animals belonging to every class ; its existence in a given species is nearly constant. Although presenting numerous variations, it may be said to consist of a central body surrounded by a more or less modified zone of protoplasm, which gives it the appearance of a cellular element. It does not appear till the primordial ovum has ceased to multiply and begun to grow. It arises from the germinal vesicle, and appears to be formed by the nucleolar substance, which it resembles in its relations to staining fluids. It generally disappears very early in Vertebrates, while the egg is still but little developed, but in certain Invertebrates it may persist in the ripe egg, and be found even in the embryo. The author regards it as an ancestral organ which, with the nucleolar elements of the germinal vesicle, corresponds to the macronucleus of Infusoria ; the micronucleus is represented by the chromatic net- work, which alone takes part in the phenomena of fecundation. Centrosome and Yolk-nucleus. § — Though M. E. G. Balbiani has investigated these bodies in Spiders, where he finds the yolk-nucleus * 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. t 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 Journ. de l’Anat. et de la Physiol., xxix. (1893) pp. 1-39 (1 pi.). § Tom cit., pp. 145-79 (2 pis.). 604 SUMMARY OF CURRENT RESEARCHES RELATING TO to be the homologue of the centrosome (or Nebenkern) of seminal cells and of the centrosome of somatic cells, his remarks are of general interest. It arises from the nucleus of the young egg, from which it becomes separated as a small bud, at the moment when the egg leaves the epithelial or germinal layer of the ovary to continue its development in the ovarian follicle. The vitelline nucleus exercises on the protoplasm of the egg an influence analogous to that which the centrosome exercises on the protoplasm of ordinary cells ; it con- denses on its surface the surrounding vitellus, in the form of a more or less thick layer, the appearance and arrangement of which vary with the age of the egg and the species of the animal. This peripheral layer of the vitelline nucleus is comparable to the plasmic mass which is called attractive sphere in other cells. Another analogy which the vitelline nucleus presents to the centro- some is its occasional existence in a double form. The size of this nucleus generally increases with that of the egg, so that it equals or may be larger than the germinal vesicle. This growth is a true hypertrophic degeneration due to the superabundant nutrition of an element which has passed into a state of physiological inactivity. The vitelline nucleus does not appear to be formed in certain Araneids, or, if it is, it disappears early, or is so fine that it cannot be perceived with the means as our disposal. In other Araneids it can be easily observed at all periods of development of the egg and embryo. The theory of Boveri regarding the physiological decadence of the female centrosome is confirmed by the author’s observations on Spiders ; their vitelline nucleus may, in fact, be considered as the female centro- some which has become degenerate, and lost its physiological signifi- cance in the life of the cell. The formation of a vitelline nucleus deprived of its normal properties is a phenomenon which has something more than a mere atavistic signification ; it is a “ phylogenetic reminiscence.” As there is a homology between the vitelline nucleus and the centro- some it is probable that these two elements have an identical origin. The nuclear origin of the centrosome explains the important part which this element plays in the reproduction of the cell. Development of Liver and Pancreas.* — Herr W. Felix has studied the development of the liver and pancreas in the Chick and in Man. In the former the first sign of the liver is to be found in the depressions of the pharynx; the walls of the intestine form two grooves which extend from the head towards the tail of the embryo, and become gradually constricted to form two distinct canals. The more anterior (cephalic) canal is situated on the dorsal side of the large veins which go to the heart, while the posterior (caudal) canal lies on the ventral side of the same veins. The caudal canal (which corresponds to the right hepatic duct of the adult) gives off two wing-like prolongations which bud into the mesenchymatous tissue. The median parts of these prolongations are hollow, while the peripheral or terminal buds are solid ; as they meet the buds anastomose, and form the hepatic plexus. * Arch. f. Anat. u. Physiol., 1892. See Journ. de l’Anat. et de la Physiol., xxix. (1893) pp. 143 and 4. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 605 The cephalic duct forms hut a small part of the hepatic tissue. The buds of the two ducts unite in such a way that the liver gradually takes on the form of a single organ which surrounds the venous sinus. The gall-bladder is developed from a diverticulum of the caudal canal. Once formed the liver loses most of its connections with the caudal canal, and there is then formed the plexus of excretory ducts which brings the hepatic mass into relation with the cephalic canal, which contributes so little to the development of the organ. The caudal canal persists as the cystic-enteric duct. The author has been able to study three human embryos ; he finds that the mode of development of the liver is analogous to that which he has observed in the Chick ; but the constriction which separates the canals from the duodenum begins early, and so causes the length of the ducts. Like Goette, Felix finds that the pancreas of the Chick arises from three foundations, one dorsal and two ventral ; all three are diverticula of the anterior part of the intestine. The same seems to be true of Man, save that the ventral diverticula fuse. Development of Mustela ferox.* — Dr. A. Robinson has some notes on the early stages of development in the Ferret. He was able to see two primitive germinal layers, and he points out that if it is right to call the inner one hypoblast the remainder of the cellular wall with which it is continuous is also hypoblast ; in this case the blastocyst is essentially a large yolk-sac which bears upon one pole a small area of epiblast. If this be so, the ovum of the Ferret, as well as those of the Rat and Mouse, bear testimony to the descent of the Mammalia from a large-yolked protamniote ancestor, for it shows during its early stages the typical features of all comparatively large-yolked vertebrate ova. No trace could be seen of any difference in thickness of the margin of the germinal area such as would indicate the existence of a widely open true blastopore, nor was there any trace of such an aperture within the area itself. Development of Mammalian Dentition.f — Dr. W. Leche begins an important essay with some criticisms and cautions in reference to some of the numerous recent publications on the dentition of Mammals. Some of these seem to him to be unduly rash. He indicates what is the safe method of investigation. By means of continuous serial sections the author has for many years been accumulating facts in regard to the development of the teeth and the relations of the two dentitions. He begins with the hedgehog. The formula of its normally persistent dentition is — i. 1, i. 2, d i. 3 ; C ; d. p. m. 2, p. m. 3, p. m. 4, m. 1-3 i. 2, d. i. 3 ; d. C; d. p. m. 3, p. m. 4, m. 1-3* The functional replacing teeth are — i. 1, i. 2, C, p. m. 3, p. m. 4 # i. 2, p. m. 4 ’ * Anat. Anzeig., viii. (1893) pp. 116-20 (2 figs.), f Morphol. Jahrb., xix. (1892) pp. 502-47 (21 figs.). 606 SUMMARY OF CURRENT RESEARCHES RELATING TO the corresponding teeth which these have replaced would in ordinary terminology be called milk-teeth. But what is to be said of those teeth which persist without replacement, viz. — d. i. 3, d. jp. m. 2, m. 1-3 9 d. i. 3, d. C., d. jp. m. 3, m. 1-3 ’ Morphologically these belong to the same series as the so-called milk- teeth. On at least some of them replacing teeth are represented by distinct bud-like enamel-germs with corresponding mesodermic thicken- ings. The so-called molars develope from the enamel ridge in precisely the same manner as the preceding milk-teeth. The hedgehog has a complete milk-dentition, but the replacement is less perfect than in most Placentalia, thus what persists is partly due to the first set, partly to the second. But in connection with the third upper incisor (d.i. 3) and some others, there are hints or residues of a still earlier generation of teeth, so that what we call the first and second set should be called second and third. Nor is the possibility of development exhausted in forming what is called the second set, for there are hints of yet another. The dentition of certain fossil Erinaceidse agrees with the first set rather than with the second. Omitting what the author says in regard to shrew and cat, we shall notice his interpretation of the marsupial dentition. He confirms some of Kukenthal’s work. The second set of teeth is represented by bud- like enamel-germs, partially surrounded by thickened connective-tissue, which at a certain stage are associated with all the teeth in front of the third molar. But of these germs only one, the third premolar, developes into a functional tooth. All the persistent teeth of marsupials, except the third premolar, correspond to those of the first set in Placentals. Reasons are given for believing that a complete second set never existed in Marsupials. In connection with Edentata, it is noted that in embryos of Tatusia peba there are rudiments of more teeth than do subsequently become calcified. The dentition of Dasypodidae is not strictly homodont ; only the first and eighth tooth are simple cones, those intervening (in the first set) have a median tubercle and a lower lateral one. In regard to Cetacea, the author states that the persistent dentition of toothed whales (all ?) corresponds to the first set in other Placentals. The teeth of the second set (replacing teeth) are not descendants of those of the first set (milk teeth), but develope lingual- wards to these direct from the enamel ridge. Reasons are given showing that the first set may be regarded as ontogenetically and phylogenetically the older. Four stages of dentition may be established : — (1) The persisting dentition consists wholly of the first set (Odontoceti). (2) The persisting dentition consists of the first set excepting the third premolar (Marsupials). (3) The persisting dentition consists of molars of the first set, w hile incisors, canines, and premolars are partly of the first and partly of the second set (Hedgehog). (4) The persisting dentition consists, excepting the molars, only of the elements of the second set (higher Mammals). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 607 There are two kinds of “ monophyodontism ” in Mammals. In the lower forms it is due to a non-appearance of the second set ; in the higher forms it is due to a suppression of the first set. In higher Mammals the monophyodont state is always the result of regression, but this is not the case in Marsupials at least. It seems likely that the second set has been gradually acquired by the Mammals. Prof. Leche closes with a discussion of the differentiation of the various types of dentition. His detailed memoir will be looked for with expectation. Development of Urino-genital System in Birds.* — Prof. C. K. Hoffmann has investigated this in various Grallatores and Natatores ( Totanus , Vanellus, Larus , Sterna , Tringa , Fulica , &c.), whose embryos are preferable to those of the fowl. All the embryos were taken from the nest, the abnormalities of artificial incubation being thereby avoided. In the present memoir the author deals with the development of the gonads, the supra-renal capsules, and the oviducts. As to the kidneys, he has not yet obtained satisfactory results. As is well known, the gonads, at first in a sexually indifferent state, develope from a patch of germinal epithelium on the wall of the abdo- minal cavity. At the expense of the lateral germinal epithelium, the Mullerian duct developes ; the median part forms the gonads with its large “ primitive ovules.” These are present in very early stages, e. g. in embryos with thirty-two somites, among the peritoneal cells. In fact, it seems impossible to state when they originate. They are not “privileged ” peritoneal cells at all events. The origin of the “ cordons genitaux ” from the Malpighian corpuscles , and their subsequent relation to the genital epithelium are described. In Grallatores and Natatores the right gonad developes for a con- siderable time as strongly as does the left. The Mullerian duct is at first equally developed in both sexes. Thus it is very difficult to distinguish at an early state embryo males from embryo females ; subsequently it becomes easier by the reduction of the genital “ cordons ” in the female. The history of these “ cordons ” in both sexes is described in detail. That each individual is originally hermaphrodite is more clear than ever. The author then describes the origin of the supra-renal capsules from nerve-strands of the sympathetic and renal strands from the Malpighian corpuscles of the Wolffian body. The Mullerian duct is formed quite independently of the Wolffian duct ; it begins as an invagination of peritoneal cells, but grows on its own account. Gastrulation in Chelonia.t — Prof. K. Mitsukuri has studied the process of gastrulation in Chelone caouana, and publishes a preliminary notice of his results. Over the great part of the blastoderm there is a separation into a superficial epiblast of columnar cells, and a lower com- posed of irregular stellate cells, and probably not forming a complete membrane. At the posterior end there is a small area in which this separation does not take place, and there is then a thick knob consisting of a reticulated mass of cells in the formation of which the subjacent yolk takes part ; this is the primitive plate or primitive knob. In the middle of this knob an invagination appears, which is the archenteron, * Verh. K. Akad. Wet. Ainstel., 1892, 54 pp. (7 pis.). t_Anat. Anzeig., viii. (1893) pp. 427-31 (8 figs.). 608 8UMMARY OF CURRENT RESEARCHES RELATING TO and its dorsal opening is the blastopore. This cavity extends gradually forwards as the primitive knob enlarges anteriorly. The roof of the archenteron, which becomes continuous with the epiblast at the dorsal lip of the blastopore, becomes columnar ; and from the median part of the roof the notochord and gastric mesoblast are formed. On the floor of the archenteron becoming divided into two parts the larger and posterior portion gives rise to the peristomial mesoblast, while the rest is finally absorbed, together with that part of the primitive knob which lies beneath it ; the archenteron is thus put into communication with the large subgerminal cavity in the yolk. The primitive knob continues to spread till the whole of the ventral surface of the embryonic shield has been covered. At some distance back from the anterior end of the embryonic shield the head-fold is developed. As the primitive knob marks the posterior end of the embryo, and the lateral folds arise within the embryonic shield, it would appear that the future embryo- body is developed entirely within the area covered ventrally by the part derived from the primitive knob. In other words, the epiblast of the embryonic shield gives rise to the epiblast and its derivates ; in the region of the primitive plate and its anterior enlargement there are produced the archenteron, the yolk-plug, the notochord, the mesoblast, the definite hypoblast and its derivates. The only contribution to the body of the embryo made by the primitive lower layer is to be found in some of its cells which are mixed up with the cells of the primitive knob. Looking at the matter generally, the author is led to the view that the enclosure of the yolk of the. Chelonian egg is a simple growth of the edge of the blastoderm, and is cenogenetic in nature, while in Elasmo- branchs it is a part of the process of invagination, and is palingenetic. He rejects, therefore, Balfour’s theory of a yolk-blastopore in Sauropsida. Life-history of Rhodens amarus.* — Dr. Ad. Olt describes the peculiar metamorphosis of the embryos of this Cyprinoid Fish during their stay in the gills of mussels, the remarkable structure of the sexually mature female, and the system of currents within the bivalve. The Bitterling is widely distributed in Central Europe. It spawns from the middle of May to the middle of July, laying its eggs within species of TJnio and Anodonta. An ovipositor is inserted at the exhalant aperture, and the ova pass into the interlamellar spaces of the gills. The nature of the ova and the mode of their transmission are described in detail. Milt is shed by the males near the respiratory siphon. While the ova enter against the stream, as above noted, the spermatozoa follow the currents. After a few notes on the segmentation of the ovum, Dr. Olt describes the embryos. Very remarkable is the manner in which the yolk serves as an attaching and protective organ. The precise relations of the embryos to the gills are noted. The females are remarkable in having an ovipositor and an accessory gland. The ovary is single, but was originally paired. In the posterior part of the body-cavity, covered by peritoneum, lies the paired accessory gland with a common duct, which may be regarded as the beginning of * Zeitschr. f. wiss. Zool., Iv. (1893) pp. 543-75 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 609 the ovipositor tube. The latter is really a modification of the skin, which is retracted by a muscle and stretched by the entrance of an ovum and associated mucus. On the mature male there are well-known warts, which the author regards as integumentary modifications of the nature of tubular glands. The bitterness of the fish is due to the bile which is always abundant in the very large gall-bladder. Elimination of Nuclear Elements in Ovarian Ova of Scorpaena scrofa.* — Prof. Ch. Van Beneden has observed this in ovarian ova of the second phase — the phase of growth. The elimination affects the chromosomes only, the nucleoli take no part. After giving an account of analogous eliminations observed by other investigators, the author discusses possible interpretations. He does not think that there is any essential difference between the eliminating process and nuclear gemma- tion ; he is sure that the process is not artificial nor pathological ; it is a reduction of chromosomes. The eliminated elements are usually disposed in the vitellus at an equal distance from the germinal vesicle and from the periphery, but their fate is unknown. Experimental Embryology. — Prof. 0. Hertwig f has made a number of experiments with the developing ova of the frog, modifying their segmentation by gentle compression between two slides or by confining them within glass tubes. The deviations corroborate a conclusion which Hertwig stated, in 1884, that the two poles of the nuclear spindle, by which the direction of the segmentation-plane is defined, come to lie in the direction of the largest protoplasmic masses. Thus, in ova forced to assume a barrel-like form within a glass tube, the poles of the first segmentation always lie in the longitudinal axis of the tube. According to Hertwig, the results of his experiments, of which we have given only a general indication, go to show that it is not the segmentation which separates the ovum into qualitatively diverse parts such that each part has but limited developmental possibilities ; the predisposition is already in the unfertilized ovum. Herr D. Barfurth J criticizes recent work in regard to the terato- logical development of Ascidians. He opposes the conclusion of Chabry that the embryo obtained after the destruction of one of the two first blastomeres was a complete embryo of half size, and supports Roux in maintaining that a typical half-morula, half-gastrula, and a right or left half-larva is produced. He points out that Chabry describes the normal Ascidian larva as asymmetrical, the left eye and left otolith being undeveloped. In describing his teratological larvae, however, he describes them as complete, except that organs of “ slight importance,” such as the otolith or a fixing papilla, are wanting. By a detailed con- sideration of the larvae described by Chabry, Herr Barfurth endeavours to prove that these are in reality half-larvae, the complete appearance being produced by the fundamental want of symmetry or by the post- generation of Roux. By this means the divergent results of the two investigators are harmonized. Herr Barfurth also notes that in an investigation of his own as to * Bull. Acad. Belg., xxv. (1893) pp. 323-64 (2 pis.' t SB. K. Preuss. Akad. Berlin, 1893, pp. 385-92. i Anat. Anzeig., viii. (1893) pp. 493-7. 610 SUMMARY OF CURRENT RESEARCHES RELATING TO the effect produced by the destruction of one of the first blastomeres in Siredon pisciformis, in the only case in which he obtained any result, a half-embryo of the right side was produced. Herr H. Driesch* finds that it is easy to shake the fertilized ova of sea-urchins so as to liberate the membranes. Membraneless ova placed under the pressure of a cover-glass, as in a former experiment by the same investigator, divide into 8-celled stages, in which the blastula consists of an annular zone of “ animal ” cells and two separated zones of “ vegetative ” cells. It is as if the “ animal ” cells formed the tropical zone, and the separated “ vegetative ” cells the polar-temperate zones. Yet from these there develope normal Plutei. “ It is there- fore proved that from a blastomere something may result quite different from that which would have resulted in normal development.” While the material of the normally “ vegetative ” half is separated into two distinct zones, the resultant gastrula has but one gut; therefore at least some of the cells which would normally have formed “ endoderm ” do in reality form “ ectoderm.” Dr. F. Braem t points out a fallacy in one of Driesch’s arguments. Driesch exposed developing ova of Echinus microtuberculatus to the pressure of a cover-glass with the result that a two-layered plate of eight cells on each layer represented the blastula-stage. “ What should have formed one pole formed the two sides, and what should have formed the other pole formed both poles.” Yet normal Plutei developed, whence Driesch concluded that the segmentation-spheres were uniform and might be arranged in any way without affecting the result. There- fore the doctrine of specific germinal areas must be corrected. But Braem notes the unproved assumption that the eight cells formed under the influence of pressure are the equivalents of the cells in the normal eight-cell stage. That this assumption is likely to be incorrect is shown in detail. Driesch’s experiment showed only that the normal form of seg- mentation may be greatly altered without affecting the ultimate develop- ment. Nor is the doctrine of His affected by the fact that one of the first two segmentation cells may form a complete gastrula, for this is simply a striking instance of regeneration, and the power of regeneration is natu- rally energetic in the immediate cell-descendants of a fertilized ovum. Heredity and the Theory of Descent. :f — Prof. C. Emery discusses the recent developments of Darwinism at some length. At the outset he explains his own position to be that of a Darwinist in the narrower sense ; he considers natural selection to be a highly important, but not the only, perhaps not even the most important factor in evolution. The first point taken up is that of secondary sexual characters. The possibility of sexual selection is granted in the case of certain birds ; in polygamous birds it is however a fact of observation that the females belong to the conqueror, and some of these birds are brightly adorned. The suggestion that the bright colours, &c., of the male serve as an indication of his strength is noticed ; it can, however, hardly account for the beautiful patterns and combinations of colour. With regard to many of these characters, as, for example, peacocks’ feathers, the pregnant * Anat. Anzeig., viii. (1S93) pp. 348-57 (16 figs.). t Biol. Centralbl., xiii. (1893) pp. 146-51. % Tom. cit., pp. 397-420. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 611 comment is made that while the morphological side of their phytogeny can be constructed with some success, their physiological origin is quite unknown. In endeavouring to throw light upon the origin of sexual dimorphism and on the wider problem of the origin of species, the author emphasizes the importance of the blood, as bringing into connec- tion the organs of the body, and thus enabling one organ to influence another which is at a distance from it. Of the importance of the con- stituents of the blood many illustrations can be given ; the evil effects often following transfusion of blood, many facts of bacteriological inves- tigation, the influence of the extirpation of the thyroid or of the supra- renal bodies, and so on. The last of these examples especially shows what an important effect the products of the metabolism of one organ may have on the whole organism. The author therefore concludes that secondary sexual characters are directly due to the varying reactions of the organs of the body to the chemical stimuli which pass out from the sexual organs. With regard to the theory of the germ-plasm, the importance of self-induced variations of its elements is especially dwelt on. If the germ-plasm, as the undying substratum in perishable organisms, begins to vary, it is conceivable that during successive generations it will continue to vary in the same direction unless new influences alter this direction. Free crossing would of course prevent this, but if the neces- sary conditions of isolation are preserved we might have a new form produced without either natural selection or the influence of environment having had any direct effect. These considerations lead the author to the conclusion that there are three types of variation: (1) The primary variations “ wdiich are the result of intimate changes in the germ-plasm, and which result in the formation of new kinds of ids, or in the alteration of the existing kinds. These variations are inherited, are apparently from their nature progressive, and may lead to the formation of new species.” (2) Secondary variations ; these arise from different combina- tions of ids which are already present in the germ-plasm, and are produced by the conjugation of cells. They are inherited and lead to individual variation ; they may however be fixed by isolation and so lead to the formation of species. (3) Tertiary variations, the result of the action of environment on the organism, are not usually inherited. With regard to the inheritance of acquired characters, variations of the third type, the author has a new hypothesis to put forward. He believes in the inheritance of certain acquired characters, such as the epilepsy of the Brown-Sequard experiments. He considers that in such cases the modified activity of certain of the organs results in the formation of certain products, probably ferments, which are taken up by the reproductive cells, and, without forming an integral part of the germ-plasm, are handed on to the developing organism, and during the development and future life exercise their proper influence upon function. This accessory part of the germ-cell he calls the zymoplasm. The paper concludes with a careful consideration of the part played by Natural Selection, in which the author emphasizes the definiteness of variation, and the fact that natural selection tends to eliminate the bad rather than to preserve the good, so that its action must be negative rather than positive as is artificial selection. On this point 1893. 2 U 612 SUMMARY OF CURRENT RESEARCHES RELATING TO Mr. Lloyd Morgan’s paper on “Natural Elimination” may be re- ferred to. Transmission of Acquired Characters.* — Herr K. Knauthe notes the following three cases which suggest to him that acquired characters may be transmitted : (1) A cow twisted one of its horns so that the point, formerly directed upwards, was turned downwards. One of its calves (a female) had the same peculiarity. (2) An ugly way of holding the tail was traced from a mare through two generations. (3) Two bull- dogs were taught to “ carry.” One of the offspring of this pair was sent away when quite young ; without any training it exhibited the habit of carrying sticks and other objects from its youth up. Inheritance of Acquired Characters.! — Prof. M. Wilckens opposes Weismann’s view on this subject on account of his own observations on artificial selection in domestic animals. He points out the undeniable fact that the characters of an English racehorse, for example, tend to be transmitted to its offspring, and by applying the term “ acquired ” to these characters he arrives at the conclusion that Weismann’s “ theory is false and cannot be reconciled with the facts.” With regard to the inheritance of mutilations he points out that all the experience of the practical breeder is against the possibility. With regard to the inheritance of characters acquired through climatic influences he asserts that measurements made in his own labo- ratory prove that, not only do cattle of the same breed vary with regard to the thickness of the hide and the length of the horns according to the climate, but that these variations are inherited. Dr. Wilckens also considers that the facts of physiology are opposed to the idea that the germ-plasma can remain uninfluenced by the nutrition and meta- bolism of the organism. In all this, however, there seems to be lacking a precise appreciation of Weismann’s position as now stated. Ontogeny and Regeneration 4 — Dr. F. von Wagner has investigated the processes of regeneration of organs, with a view to testing the validity of the common assumption that these processes run parallel to embryonic development ; that tissues and organs are reformed by cells of the same embryonic layer as that from which they first took origin. With regeneration are also included ordinary processes of asexual budding. In the budding of Hydra and some polypes, Lang § has already shown that the ectoderm and endoderm of the bud alike arise from the ectoderm of the parent. Lang endeavours to harmonize this with embryonic conditions by asserting that the ectoderm of the parent, over the budding area, is homologous with the blastoderm of the embryo. This is, however, an untenable position, and cannot conceal the fact that budding is not a repetition of embryonic development in the case of these bydropolypes. In his own experiments, especially on Microstoma , Dr. Wagner found that the pharynx was regenerated by the parenchyma of the body — that is by a mesoblastic tissue, while in ontogeny it arose from the ectoderm. The parenchyma also reformed the nerve-ring when this was destroyed. * Zool. Anzeig., xvi. (1893) p. 174. t Biol. Centralbl., xiii. (1893) pp. 420-7. X Tom. cit., pp. 287-96. § Zeitschr. f. wiss. Zool., liv. pp. 366 et seq. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 613 Although the necessary embryological data are here wanting, it is not likely that the nerve-ring was originally mesoblastic. Similar regenera- tive experiments on Lumbriculus led to similar results. The author’s conclusion is that the conception of the parallelism of ontogeny and regeneration must undergo fundamental modification, and points out the danger of filling up gaps in embryological observations with inferences drawn from processes of regeneration. The Origin of Species.* — M. Lavocat in a lengthy paper opposes the current doctrine of evolution, which he terms “ the theory of trans- formations.” He asserts that no transition form between two species has been found, either fossil or living, and that variability is so limited as to be only able to produce varieties or races and not species. The author’s own theory is that “ every species has had a special and distinct origin ; that in every case forms primitively imperfect have gradually developed; and that every species has proceeded not from a single centre, but from every region where circumstances were favourable for its formation and development.”! The question of the first origin of these primitive species is said to be unanswerable. #. Histology. Recent Views on Protoplasm. j — Enquiries are often made for some useful critical summary of recent speculations on protoplasm. This appears to have been given by Prof. W. A. Has well, who took “ recent views on the structure of protoplasm and the significance of the various parts of the cell ” as part of the subject of his presidential address to the Linnean Society of New South Wales. He thinks that some definite progress has undoubtedly been made of late in our knowledge of the relative importance of the different parts of the cell. A serious assault has been made on the predominance of the nucleus. The centrosomes or attraction spheres, first discovered by E. van Beneden, appear to be independent centres of activity, and they, with the spindle-fibres that proceed from them, appear to be of importance in cell-division ; indeed, according to Rabl and others, they form the actual vital parts of the cell. We commend the address to the enquirers to whom we have referred. The Cell.t — Prof. O. Hertwig’s admirable book should have found earlier notice in our pages. It contains in compact form an account of the more important facts in regard to the cell, stated with the author’s wonted clearness and is well illustrated. A short historical chapter is followed by a discussion of the structure, functions, and chemistry of the cell. The animal and the vegetable cell receive parallel treatment, and throughout the book the relation of the established facts to general biological conclusions is kept in the foreground. As the author admits in the preface, his own views are emphasized. This emphasis is natural, for Prof. 0. Hertwig’s contributions to cellular biology have been numerous and of great importance, but we are inclined to think that a little more space might have been found for the conclusions of other workers. The second volume will treat of tissues. * Mem. Acad. Sci. Nat. Toulouse, iv. (1892) pp. 44-65. f Proc. Linn. Soc. N.S.W., vii. (1893) pp. 673-85. X O. Hertwig, ‘ Die Zelle und die Gewebe. Grundziige der allgemeinen Anatomie und Pliysiologie,’ Theil i., 8vo, Jena, 1892, 296 pp., 168 figs. 2 u 2 614 SUMMARY OF CURRENT RESEARCHES RELATING TO Origin of the Centrosoma.* — Dr. A. Brauer records some observa- tions made on the spermatocyte of Ascaris megalocephala var. univalens , which he regards as conclusive. In the nucleus of the spermatocyte at the stage when a four-partite chromosome was present, he saw, apart from the nucleolus, a relatively large rounded body. During the formation of the first spindle, threads radiate out from this body, in all directions, to the chromosome ; it then lengthens and divides. The halves then separate, while the threads communicating with the chromosome remain unbroken ; as they separate, the nucleus becomes lengthened in the same direction. At last, at two opposite points the two bodies pass through gaps in the nuclear membrane into the cell-protoplasm. Here a radiating arrangement of cell-protoplasm becomes obvious round each. The two structures thus formed from the original spherical body are undoubtedly the centrosomes. In some cases before its division the centrosome leaves the nucleus and appears on the outside of its membrane. In this observed case it is clear that the centrosome belongs to the nucleus and not to the cell-protoplasm. The strongly accentuated distinction between nucleus and centrosome thus breaks down, and increased proba- bility is given to the view which regards the chromatin elements as the bearers of hereditary tendencies, the centrosome as simply an organ of division. The author’s observations also lead him to conclude that the whole of the spindle is nuclear in origin. Muscle-spmdles.f — Dr. L. Kerschner gives a useful summary of investigations (since 1888) on muscle-spindles. He dismisses various interpretations, e. g. that they are pathological growths, or that they are merely transitional structures. Most striking is the well-developed terminal nerve-apparatus. This cannot be motor, for on each of Weismann’s fibres there is at least one motor terminal plate, and there is no connection between the terminal apparatus and the motor tracts. Kerschner’s own interpretation is that the apparatus is sensory. In support of this he marshals various arguments, and promises a fuller statement. Intercellular Bridges between Smooth Muscle Cells and Epithelial Cells.t — Dr. M. Heidenhain finds that in the poison-glands of Triton the ensheathing muscle-cells are connected by plasmic bridges with the ectodermic epithelial cells at the neck. He regards this connection as of primary significance, and as a proof that these muscle-cells of the skin-glands belong genetically to the ectoderm. In the case of the pelvic and cloacal glands he believes that the muscle-cells are in the same way demonstrably endodermic. y. General. Nerve-cord and Notochord in Amphioxus.§ — Herr B. Lwoff dis- cusses the import of the supporting fibres associated with the nerve-cord of Amphioxus. Those which lie ventrally are the strongest. The ependyme cells, homologous with similar elements in other Vertebrates, form the original supporting tissue, and remain much more distinct and * Biol. Centralbl., xiii. (1893) pp. 285-7. t Anat. Anzeig., viii. (1893) pp. 449-58. J Tom. cit., pp. 404-10 (1 fig.). § Zeitschr. f. wiBS. Zool., Ivi. (i893) pp. 298-309 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 615 primitive than in higher forms. The vesicular epithelial tissue of Sigalion and other Annelids — a tissue which serves for the fixing of the supporting elements of the nervous system, and also for the insertion of the musculature — corresponds to the notochord of Amphioxus. It may be remembered that according to Lwoff the notochord of Amjphioxus arises from the ectoderm, differentiating from a rudiment from which nervous system and lateral musculature also develope. The above- mentioned supporting tissue of Annelids is also ectodermic. It has a developmental, histological, and functional correspondence with the notochord of Amjphioxus. B. INVERTEBRATA. Mollusca. Land and Fresh- water Mollusca of New Zealand.4" — Messrs. C. Hedley and H. Suter have published a reference list of these Molluscs which should be useful to students and residents. They remark that as the New Zealand fauna becomes better known, its insularity stands out more prominently. One by one foreign genera that have been falsely imposed on the fauna by the negligence of collectors or the mistakes of authors, have been eliminated. All the species are now known to be strictly endemic, and the relation to North Australia has been shown to be based on fictitious evidence. One hundred and eighty- four species are catalogued. a. Cephalopoda. Coloration of Integument of Cephalopoda.f — Dr. L. Joubin finds that the development of the chromatophore commences with the invagi- nation of an ectodermic cell into the mesodermic connective tissue; it gradually sinks in, and ends by forming the base of an ectodermic depression from which it, finally, becomes detached. It then becomes connected with some mesodermal connective cells which are applied to its surface ; it grows, dilates, and disposes its contents in two zones, the inner of which is the denser. The nucleus, which is at first distinctly visible, becomes less and less well marked as the chromatophore becomes complete. Meantime, the mesodermal cells increase rapidly in number, and form a corona of cells for the ectodermic cell, which is now lenticular in shape. The peripheral cells become contractile and soon fibrillated, when they serve to fix the principal cell to the surrounding tissues and maintain it perfectly distended, so as to allow of the play of the coloured protoplasmic contents. This double transformation of the peripheral cells into muscular, and thence into connective fibres, explains the two opposing views that have been held as to the constitution of the chro- matophore. It is, at the same time, clear that the fibres, even during their muscular phase, have no action on the coloured protoplasm, which is animated only by amoeboid movements of expansion. In studying the coloration of living animals, the author applies a process of staining which has, as yet, been only used for Fishes and 616 SUMMARY OF CURRENT RESEARCHES RELATING TO Batrachians. This consists either in injecting a highly concentrated solution of metliylen-blue into the veins of an adult, or of making a very dilute solution in the sea-water in which the embryos of Cephalo- pods are living. The latter gradually accumulate the colouring matter in their integument without any apparent injury to the animal. The injection of a concentrated solution into an adult very rapidly shows up the cutaneous nervous network which is peculiar to the chromatophores. The terminal fibres of the nerves may be seen ending in a swelling in each of these organs. The immersion of embryos in coloured sea-water rapidly leads to the appearance of the sinuous lines of the special cells ; the network of nerves soon becomes evident, and their termina- tions are seen even better than in the adult. If the staining be deeper the nerve-centres which preside over the movements of the chromatophore become very sharply coloured. These centres are the pallial ganglia, which are united by a transverse commissure which has never yet been described. The author has investigated the cutaneous glands of Eledone moscliata ; he finds that the skin of this Cephalopod contains very large mucous epithelial cells in which there is a large droplet of fatty matter, which is the “ musk.” The contents of these cells are probably a mixture of fatty and volatile matters which are soluble in ether ; the residue obtained dry in small quantities only is of a yellowish colour and strongly odorous. Finally, the author discusses the cutaneous ink-secreting organs of Nautilus. As a Nautilus grows it comes in contact by its back with a part of the shell which has been for a more or less long time exposed to shocks from without, and has become rugous. It covers this part with a black varnish secreted by the edge of the mantle. This varnish is itself, some time later, covered by the nacre which is also secreted by the mantle. The part of the mantle which is charged with the deposit of varnish is the superficial cutaneous epithelium, modified in a special region for this secretion. The cells of this region are caliciform and curved ; they secrete very fine black granulations which accumulate in the cuplike part, and are deposited in the successive zones of the shell with which they come into direct contact by their large orifice. y. Gastropoda. New Classification of Helices.* — Mr. H. A. Pilsbry invites considera- tion of a classification of the Helicoid snails which is, he says, essentially modern and essentially original. In dissecting the male generative organs of snails, note should be made of (1) the shape of the penis, (2) the presence or absence of internal papilla and external appendix, (3) presence or absence of flagellum or epiphallus, and (4) the point of insertion of the retractor muscle and of the vas deferens. In the female system the presence or absence and the form of dart-sacs, darts, mucous glands, should be noticed, as well as the length of the spermathecal duct, the form and position of the caeca of the ovotestis, and, finally, whether the right eye-peduncle is retracted between the branches of the genitalia or to the left side. With regard to the value of the jaw as a basis for classification there * Proc. Acad. Philadelphia, 1802, pp. 387-404 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 617 are still a number of unsettled questions, but on some points there is more certainty. It may be confidently asserted that the strongly ribbed type of jaw (odontognath) intergrades by imperceptible stages with the entirely smooth, Zonites-like type (oxygnath). “ Odontognathy ” and “ oxygnathy ” are therefore “ controvertible terms,” as far as classifica- tion is concerned, and consequently cannot be used for the separation of genera or even sub-genera. The primary groups recognized by the author are : — I. Eggs or young very large at birth. (1) Macroon. II. Eggs or young smaller or minute at birth. a. Female system with dart-sac and mucous gland. (2) Belogona. aa. Female system without accessories ; male with flagellum and appendix on penis ; no epiphallus. (3) Teleophalla. aaa. Female ditto, male with epiphallus, but no appendix. (4) Epiphallophora. aaaa. Genital system lacking all accessory organs. b. Jaw soldered into one piece. (5) Haplogona. bb. Jaw composed of 16-24 separate plates. (6) POLYPLACOGNATHA. Mr. Pilsbry defines his groups and gives short notices of the consti- tuent genera of each. Integument of Zonites cellarius.* — M. E. Andre notes certain pecu- liarities in the integument of this Mollusc, which have not yet been described. These peculiarities, which obtain in no other Pulmonate Gastropod, consist of crypt-like organs solely formed on the right side of the body, where they extend from the genital orifice to the mouth, and from the upper boundary of the foot to the middle of the dorsal surface of the body. These crypts are formed by invaginations of the external epithelium, and are 1/4 to 1/3 mm. deep. They vary in form, being sometimes simple, sometimes more or less branched, and are sometimes provided with swellings. The epithelium of these organs differs from that of the surface in that the cells and their nuclei are more elongated ; they have no vibratile cilia. The dorsal surface of the body is peculiar in the presence of very large mucous cells, so closely packed as to form an almost uninterrupted layer. It is not at present possible to suggest what is the function of the crypts. Development of Umbrella mediterranea.f — Dr. R. Heymons makes an important contribution to our scanty knowledge of the development of Opisthobranchs. The formation of three generations of micromeres, their further multiplication to the 24-cell stage, the subsequent division of a macromere, and the associated origin of the mesoderm are facts in the development of Umbrella, which are in essential harmony with what is known to occur in Planorbis, Neritina , and Crepidula, but they have not been previously observed for Opisthobranchs. After a careful comparative study, the author goes on to discuss the excretory organ. His most important result is a demonstration of the entirely ectodermic * Zool. Anzeig., xvi. (1893) pp. 39 and 40 (1 fig.), f Zeitschr. f. wiss. Zool., lvi. (1893) pp. 245-98 (3 pis.). 618 SUMMARY OF CURRENT RESEARCHES RELATING TO nature of this structure. The mesoderm takes no part in its formation. It may be compared with the so-called external primitive kidney cells of Prosobranch embryos, but the suggestion of a complete homology would be premature. Homalogyra.* * * § — M. A. Vayssiere has a preliminary notice of his investigation of this genus, formed in 1867 by the late Dr. Gwyn Jeffreys. He finds that it has two dorsal tentacles of some length, and that the radula has not been correctly delineated either by Sars or Jeffreys. He gives amended diagnoses of the family and generic characters. The species studied appears to be H. atomus , which was found for him off Marseilles. Structure and Habits of Jorunna Johnstoni.f — Mr. W. Garstang, in a short note on this Nudibranch, states that it lives on the same stones as the small Halichondrise which it so closely resembles. The form and general colour of the Mollusc and the Sponge are very similar, and there are even the same slight variations in tint. The only external difference is presented by the two dorsal tentacles of the Nudi- branch, but the presence of conspicuous spots on the back of the animal, coloured doubly like the tentacles, and arranged so that the tentacles are included in the same series, effectually deceives the eye and conceals almost entirely the projecting tentacles. It is to be remembered that the author has shown that sponges are shunned by predatory fishes under both natural and artificial conditions. Branchial Sensory Organs of Patellidge.j: — Dr. J. Thiele describes an organ in Patina pellucida which forms a knob-like projection of the epithelium, at the sides of the body between the foot and the mantle. It is supplied by a delicate nerve from Spengel’s olfactory ganglion, which is somewhat difficult to detect between the fibres of the retractor muscle. The epithelial band presents the characters of sensory epithelium. Neomeniid3e.§ — Dr. H. Simroth begins his study of these interesting types with a compact summary of what is known in regard to their structure. Passing over this we find the following genera suggested for the twenty-six known species : — Genus I. Neomenia Tullberg ; II. Pro- neomenia Hubrecht ; III. Solenojpus Sars ; IY. Phopalomenia g. n. ; Y. Macellomenia g. n. ; YI. Dondersia Hubrecht; VII. Nematomenia g. n. ; VIII. Myzomenia g. n. ; IX. Paramenia Pruvot ; X. Ismenia Pruvot ; XI. Lepidomenia Kowalewsky et Marion ; XII. Echinomenia g. n. Simroth attaches much importance to the fact that the Neo- meniidge are distributed between the littoral and the abyssal fauna. They avoid the surface region, keeping out of the reach of waves, whereas the Chitonidge are surf-animals with dorsal armature and broad suctorial soles. Pruvot’s discovery that Myzomenia banyidensis bears in its youth the dorsal plates of a Chiton shows that the Chiton-type is the more primitive. The passage of the Neomeniidee from the zone of rapidly moving water to quieter regions is supposed by Simroth to have been associated with the loss of protective shells, the narrowing and * Comptes Rendus, cxvii. (1893) pp. 59 and 60. t Conchologist, ii. 3 (1892) 4 pp. (sep. copy). X Zool. Anzeig., xvi. (1893) pp. 49 and 50. § Zeitschr. f. wiss. Zool., lvi. (1893) pp. 310-27. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 619 degeneration of the sole, the approximation of the genital pores, a change to carnivorous diet, with the consequent shortening of the gut, and other characteristic features. S. Lamellibranchiata. Gills of Lamellibranchs.* — Dr. F. Janssens appears to find himself in greater agreement as to the morphology of the gills of Lamellibranchs with the late Mr. Peck than with any other of the numerous observers of these organs. The author commences his account of his own observations by describing the general anatomy of the gill in various forms. In con- sidering the histological constitution of the gill he deals separately with the parts formed from the mesoblast and from the hypoblast, but his method of description, in which he constantly refers to figures, and the complete absence of any general deductions, make the paper one which can only be properly studied with the illustrations at hand. Molluscoida. a. Tunicata. Perivisceral Cavity of Ciona. f — Mr. A. H. L. Newstead finds that the primary condition of the epicardium is undoubtedly that found in Clavel- lina , where it has the function of a budding organ. In Ciona there is considerable modification and loss of the original function. The view of Herdman that the stolons of Ciona are modified budding organs appears to be correct. The view of Koule that the perivisceral cavity of Ciona is a primitive condition is not supported by Mr. Newstead’s observations, which point rather to the cavity being a specially modified epicardium which has become greatly enlarged. The space in question is certainly not homologous with the general blastocoel space of Appendicularia ; and there are no reasons for supposing that the other simple Ascidians pass through a stage in which the epicardium is enlarged as in Ciona ; in fact, so far as the perivisceral cavity is concerned, Ciona is the most modified of the simple Ascidians. Development of Tunicates.J — Herr J. Hjort finds that the only kind of budding in Botryllidse is that described by Metschnikoff and Della Yalle as pallial, and that the stolons are purely ectodermic in origin. He describes the early stage of the bud in which there is a median vesicle, from the dorsal part of which the blind dorsal tube grows forwards, while the two peribranchial vesicles appear laterally. In the posterior third of the bud these structures are all connected, and from this region the coiled gut grows backwards. The dorsal tube differen- tiates into hypophysis and permanent ganglion. In regard to the heart, Hjort observes that it arises from an unpaired compact mass of cells on the right side. As to the gonads, the results of Della Yalle are confirmed. From a study of the larva of Distaplia magnilarva , the author comes * La Cellule, ix. (1893) pp. 71-91 (4 pis.). t Quart. Journ. Micr. Sci., xxxv. (1893) pp. 119-28 (1 pi.). J MT. Z. Stat. Neapel, x. (1893) pp. 584-617 (3 pis.). 620 SUMMARY OF CURRENT RESEARCHES RELATING TO to the following conclusions: — (1) The larval and the persisting nervous system arise from the same rudiment as the hypophysis, viz. the original ectodermic invagination which forms the cerebral vesicle ; (2) the larval cerebral vesicle is, during the later larval period, in communication with the gut through the future hypophysis ; (3) the anterior part of the hypophysis arises directly from the anterior region of the elongated cerebral vesicle, the posterior part from the left epithelial wall of the same ; (4) the lumen of the hypophysis is, in the adult, the only per- sisting residue of the larval cerebral cavity ; (5) the persistent brain of the adult arises from the thickening of the left wall of the cerebral cavity from which the hypophysis grows out. y. Brachiopoda. New Classifications of Brachiopoda.* — Miss Agnes Crane has a critical notice of some recent modifications in the taxonomy of Brachio- pods. Mr. C. Schuckert has published in the * American Geologist ’ (xi. 3) a classification “based on the history of the class (chronogenesis) and the ontogeny of the individual.” Beecher’s suborders of Atremata, Neotremata, Protremata, and Telotremata are adopted as orders; the Protremata are divided into the Trullacea and the Thecacea ; in all nine new families are added. Mr. C. E. Beecher published, in March last, a “ revision of the families of loop-bearing Brachiopods ” ; he divides the Terebratellidse into the three well-defined families of Dallininae, Magellaniinas, and Megathyrinm. Both branches of the Terebratellidae appear to have originally sprung from some minute form allied to the existing Gwynia, which, doubtless, lived before the Jurassic period, and to which palaeontologists should turn their attention. Miss Crane con- siders that the advances in our knowledge of the genealogy of the recent Brachiopods are such as to have brought us to a turning-point in the history of the race. Arthropoda. Classification of Tracheate Arthropoda.t— Mr. R. I. Pocock urges that the Tracheata may be considered to consist exclusively of the Myriopoda and Hexapoda, and inquires whether the group, as thus limited, is a natural one. After pointing out the well-known characters which the two classes have in common he remarks that the division into Myriopoda and Hexapoda is based principally upon the external form. On further examination, however, it is clear that the so-called group of Myriopoda is sharply divisible into two sections upon a character which admits of no exception. This character is the position of the generative organs. In the Pauropoda and Diplopoda the genital orifices are situated near the anterior end of the body, while in the Chilopoda and Symphyla ( Scolopendrella ) they are placed at the posterior end, quite close to the anus ; this latter position is that which is seen also in the Hexapoda. Now various writers have pointed out that Scolopendrella is closely related to the Thysanura, and the author remarks, no one who compares a Scolopendrella with a Chilopod on the one hand and with a Thysanurous Hexapod, on the other can avoid being struck by the fact that the differential characters between the Insects and the Centipedes * Geol. Mag., x. (1893) pp. 818-23. f Zool. Anzeig., xvi. (1893) pp. 271-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 621 are to a large extent bridged over, and that Scolopendrella must conse- quently be regarded as the living form that comes nearest to the hypo- thetical ancestor of the two great divisions of Tracheates. Mr. Pocock proposes to divide the group into two sections, one to contain the Pauropoda and Diplopoda, the other the Chilopoda, Symphyla, and Hexapoda ; the former may be called Progoneata, the latter Opisthogoneata. If the affinities between the Symphyla and Chilopoda are greater than those between the Symphyla and the Hexapoda, a group Homopoda may be formed to contain those two orders of Myriopoda. Phylogenetically the classification is represented thus : — • Diplopoda Pauropoda v / K. Progoneata Chilopoda Hexapoda Symphyla / s -/ Opisthogoneata Tracheata a. Insecta. Life-history of Cochliopodidse.* — Prof. A. S. Packard gives accounts of the life-histories of some members of this family of Moths. He finds that the young, like the fully formed, larvae have no traces of abdominal legs. The shape of some of the young is such as to suggest that either the Cochliopodidae have originated from the Saturniidae or forms allied to them, or that both these families have descended from a common stem-form, which was, perhaps, Notodontian. The tuberculated larvaa of Euclea, Adoneta, and Empretia are those that are most like the larvae of other Bombyces. Some of them, probably from adaptation to a series of causes unlike those which affect any other caterpillars, might easily be mistaken for a fold or bend in a leaf. Others, such as the larvae of Heterogenea, are wonderfully similar to the red dipterous or aphidid galls on oak and other leaves. It is now of importance to determine how late in embryonic life the abdominal legs disappear. The forms of which the author gives more or less full life-histories are Empretia stimulea, Euclea querceti , Parasa chloris, Adoneta spinuloides, Phobethron sp., Limacodes scapha, Pachardia elegans , Lithacodia fasciola , and Heterogenea spp. Nutritive Relations of Lepidoptera.f — Dr. Ad. Seitz discusses thirty-three points of interest concerning the nutritive relations of Lepidoptera. The arc of possible oscillation is often very wide, much wider than in most other insects; abnormal diet, scarcity, periodic * Proc. Amer. Phil. Soc., xxxi. (1893) pp. 83-108 (4 pis.), t Zool. Jahrb. (Abtli. Syst., &c.), vii. (1893) pp. 131-86. 622 SUMMARY OP CURRENT RESEARCHES RELATING TO absence of food, &c., can be survived. The various effects of diminished nutrition on the individual, on pupation, on the number of offspring, are spoken of. It is recognized that fasting may be associated with pro- gress. The choice of food-plants and its motives, the causes of change of diet, cannibalism, the influence of nutrition on reproduction, the rate of growth and its limit, moulting, and water-drinking are among the subjects discussed in this essay, which is full of interest to the student of biology and bionomics. Evolution of Papilionidae.* — Prof. G. H. Th. Eimer answers a criticism brought against him by Herr A. Spuler. f By his study of Lepidoptera Eimer endeavoured to show how species arise “ by definite modifications in a few directions,” one species differing from its nearest neighbours in the relative predominance of certain characters — in short, that species form definite morphological series. The specific distinctions are not only not indefinite, they are not explicable on a utilitarian theory. Eimer supported this view in a large work and atlas ; Spuler disputed the accuracy of certain facts and the legitimacy of the conclu- sions ; Eimer answers that Spuler fails to make good his criticism, and that he has not read the book with sufficient care. Respiratory Phenomena in Chrysalids of Silk Moth.f — Prof. L. Luciani and Dr. D. Lo Monaco have made daily and nightly quantitative estimates of the amount of C02 given off during twenty-two days. The oscillations demonstrate that the life of the chrysalis may be divided into four periods: — (1) Along lethargy of four days, (2) a long activity of seven days, (3) a short lethargy of two days, and (4) a short activity before emergence. The authors, of course, regard the fluctuations in the amount of C02 liberated as indices and, to some extent, measures of the intensity of the vital processes occurring within the chrysalid. Remarkable Behaviour of the Spermatozoa of Dytiscus margi- nalise— Prof. L. Auerbach has observed the spermatozoa in their passage through the convoluted seminal vesicles. All those arising from one testicular follicle are united in a bundle. Each has a very complex structure, bilateral but unsymmetrical. The right side of the head is concave, the left convex ; the whole head is longitudinally curved to the right or left ; and on the posterior half of the right side there is a pro- jecting ridge bearing a hook-shaped “ anchor.” Of the entire structure a careful description is given. At the free end of the cyanophilous anchor an erythrophilous spherule appears. But the most remarkable fact is that the spermatozoa unite in pairs in a perfectly definite fashion, opposed and crossed in a manner somewhat suggestive of a pair of scissors, with the right sides of the heads in contact. During this conjugation, or “ dejugation ” as Auerbach calls it, the anchors change in form, and the little spherules are lost. Hundreds of these double spermatozoa are found together in little balls. The conjugation is a temporary one, but it may permit a molecular exchange of substance, perhaps with the result of mixing the hereditary qualities and limiting variability. * Zool. Jahrb. (Abth. Syst., &c.), vii. (1893) pp. 186-205 (8 figs.). f See this Journal, 1892, p. 469 ; 1893, p. 174. t Bull. Soc. Entomol. Ital., xxv. (1893) pp. 12-24. § SB. K. Preuss. Akad., 1893, pp. 185-203 (2 figs.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 623 Chirping* * * § and Jumping Ants.* — Prof. C. Emery notes that two large American Poneridae do really chirp. In species of Paraponera and Pacliycondyla the surface of the second (or more strictly the third) abdominal segment is transversely striated and produces a chirping sound when rubbed against the margin of the segment in front. This sound Emery was able to produce artificially, and Herr A. Schulz has heard it from living specimens of Pacliycondyla flavicornis. The same observer noted that the Brazilian Gigantiops destructor Fab. springs from twig to twig, as does also Odontomachus lisematodes in similar localities. Nests of Formica rufa.f — Sig. P. Bargagli describes the heaps of pine leaves and twigs which form the superficial parts of the nests of this ant as these occur on the Tyrol mountains. What seems to be new in his description is the fact that considerable quantities of resin are accumulated by the ants in little grains and larger balls. The author has also an interesting note to make on the favourable influence which the heaps made by the ants exert on the associated vegetation. Hylotoma pagana.J — Hr. G. Del Guercio gives an account of this Hymenopterous Insect, which is known to gardeners as the yellow rose- fly. He describes the ova, the larvae, the nymph, and the perfect insect. The eggs are laid in the young branches, the larvae browse on the leaves, the chrysalids are buried in the soil at the base of the stem, the adults flit rapidly from hush to bush. Copulation, oviposition, and other events of the insect’s life are described. The eggs are readily destroyed by insecticide fluids or with a knife. Autumnal Generation of Diaspis pentagonal — Prof. F. Franceschini has discovered a third generation of this injurious insect, and points out the practical importance of his discovery. Pogonius bifasciatus F.||— Herr C. Verhoeff gives a short account of the development and life-history of this species. He found a cocoon containing a larva towards the end of August in a deserted nest of Ghalicodoma muraria. As a general rule Pogonius passes its larval stages in rock crevices. The larva took about eight months to complete its development, the imago being produced at the end of the March of the year following its capture. The nymph possesses a stinging apparatus similar to that already described for Agenia , and corresponds with the latter in several other respects. Biology of Chalcididse.f — Mr. L. O. Howard gives an account of the general economy of these parasitic Hymenoptera. Dealing first with the Insects and stages of Insects infested by them, he points out that repre- sentatives of all of the original Linnaean orders suffer from them in one or other of their stages : the orders which suffer most are the Lepidoptera, Hymenoptera, Hemiptera, and Homoptera. Information with regard to the mode of life of the Chalcidid larva is so slight and so contradictory * Biol. Centralbl., xiii. (1893) pp. 189-90. f Bull. Soc. Entomol. Ital., xxv. (1893) pp. 42-5. t Op. cit., xxiv. (1893) pp. 331-45 (5 figs.). § Atti Soc. Nat. Sci., xxxiv. (1893) pp. 285-93. II Zool. Anzeig., xvi. (1893) pp. 258-60. 1 Proc. U.S. Nat. Mus., xiv. (1892) pp. 567-88. 624 SUMMARY OF CURRENT RESEARCHES RELATING TO that it is very difficult to make general statements, and their method of respiration is quite a puzzle. There is evidently considerable variation in the rapidity of development, and, consequently, of the number of annual generations ; this variation is partly due to the particular para- site and partly to the habits of the particular host ; in some cases growth appears to be very slow. As a rule, Chalcidid larvae which are internal feeders transform internally into naked, more or less coarctate pupae. Some cause a marked inflation in the host-larva by the formation of oval cells around the parasite. From one to three thousand parasites may develope in a single host. The study of agamic reproduction will probably prove of the highest interest and importance. According to the author’s estimate, the number of species of Chalcididas will prove to be immense. British Phytophagous Hymenoptera.* * * § — Mr. P. Cameron has pub- lished the fourth and concluding volume of his monograph. In all 382 species of Tenthredinidae, 9 of Cephidae, 5 of Siricidae, 1 of Phys- cidaa, and 179 of Cynipidae have been described. The present volume contains an appendix which brings up our information to date. Copulatory Organs of Cockchafer.f — Dr. J. E. V. Boas gives a detailed and apparently complete account of the copulatory apparatus of the Cockchafer. After a general account of the parts and of their function he enters into greater detail as to special organs ; there is in the cloaca a chitinous band fused to the cloacal stylet ; the latter is of importance as a point of origin of muscles ; of these there are a number which take part in the movements of the penis. Eggs of Acridium peregrinum.J — M. R. Dubois has a note on the oil found in the eggs of this grasshopper. In colour and consistency the oil is like that of the hen’s egg ; in a short time it becomes rancid, and has the smell of cod-liver oil. It contains as much as 1*92 per cent, of its weight of phosphorus, but no sulphur. The author hopes the oil may be proved to be of use in therapeutics or commerce, when a prize would be offered for “ the destruction of the plague of our colonial agriculture.” j3. Myriopoda. Functions of Nervous System of Myriopoda.§ — Mr. C. M. Child has made some observations on the central nervous system of Lithobius , from which he draws the following general conclusions. The nervous system consists of, firstly, a series of centres which are capable, unaided, of responding to sensory stimulation by appropriate co-ordinated motions ; or, in other words, a series of complex reflex centres lie in the ventral cord. Secondly, there is situated in the head a single ganglion to which all the reflex centres are subordinated, and which contains also the centres for the eye and the antennse, and is the seat of whatever intelligence may be possessed. Steiner defines a true brain as a centre possessing a general motor centre together with the centres of at least one of the higher senses. According to this definition the supra-oeso- * London, printed for the Eay Society, 1893, 248 pp., 19 pis. f Overs. K. Danske Vid. Selsk., 1892, No. 3, pp. 239-61 (1 pi.). I Comptes Rendus, cxvi. (1893) pp. 1393-4. § Amer. Natural., xxvi. (1892) pp. 1051-5. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 625 phageal ganglion of Lithobius is a brain. The ventral cord is analogous in function to the spinal cord of some of the lower Vertebrates. Production of Light in Orya barbarica.* — M. R. Dubois has studied the mechanism of the production of light in this Myriopod. He finds that it is secreted by special organs, and can be collected in a pure state. It is found in unicellular hypodermic glands, which are pyriform in shape, 8-10 mm. long and 5-6 mm. wide. Sections one-hundredth of a millimetre in thickness, stained with methylen-blue or haematoxylin, reveal the presence of numerous rounded or ovoid drops in the granular glandular protoplasm. These drops blacken with osmic acid, and exhibit the histo-chemical characters of protoplasm or of condensed albuminoid bodies. Soon after contact with free air a highly refractive point appears at their centre, and this point becomes the centre of a crystal or rather of a group of crystals. The encrusted protoplasmic matter passes, under the eyes of the observer, from the colloid to the crystalloid state, while light is produced. While contact with air is necessary and excites the luminosity, contact with water is no less so. The author considers that we have here to do with two successive stages of the photogenous material, and for them the name luciferin may be retained until the atomic structure has been determined. 5. Arachnida. Habits of Living Scorpions. j — Mr. R. I. Pocock has some interest- ing notes on the habits of living Scorpions, two species of which — Parabuthus capensis and Euscorpius carpathicus — he has kept in captivity for some months. With regard to the latter he is able to confirm many of the observations of Prof. Ray Lankester. Though sluggish during the day they could always be roused by the application of a little arti- ficial warmth, but more than very little heat was sufficient to throw them into a state of the greatest consternation. Parabuthus , like Prio- nurus, digs shallow pits or holes in the sand, but Euscorpius was never observed to do so. All scorpions appear to be carnivorous ; they are very adroit in seizing anything that comes within reach ; they never seem to need anything to drink, unlike Spiders, which are very thirsty. The only one of the higher senses that appears to be well developed is that of touch ; and Mr. Pocock cannot substantiate the statement of M. Becker that sight and hearing are excessively developed. At a distance of more than three or four inches they cannot see a moving body. The accusation of infanticide appears to be groundless, and as to the charge of being suicidal, the author is as sceptical as Prof. Morgan, who some years ago made some observations on South African Scorpions, and various other authors. Parasitism of Pseudoscorpions.J — Prof. F. Leydig expresses his opinion that the presence of Pseudoscorpions on the bodies of other Arthropods is a case of real though temporary parasitism. In the case of a Brazilian beetle with a dense chitinous carapace the Pseudoscorpion was found below the membranous wings and the abdomen ; that is to say, at a point where the beetle was vulnerable. * Comptes Rendus, cxvii. (1893) pp. 184-6. f Nature, xlviii. (1893) pp. 105-7. X Zool. Auzeig., xvi. (1893) pp. 36 and 7. 626 SUMMARY OF CURRENT RESEARCHES RELATING TO Parthenogenesis in Spiders.* — Herr N. Damin records what he believes to be the first known case of parthenogenesis in Spiders. In the spring of 1891 he placed two living specimens of Filistata testacea in two separate tubes ; of these, one moulted twice in 1891 and once in 1892 ; on the 8th July, 1892, it spun a cocoon and laid eggs, as unfer- tilized Spiders often do ; on the 27th July the author opened the cocoon, and, contrary to all his expectation, found sixty-seven young. The young were alive on the 1st March of this year, and had already moulted once. Few, if any, observers have found the male of F. testacea on the continent of Europe, but it still remains to be decided whether the parthenogenesis of the females is an occasional, or a regularly recurrent, phenomenon. And, of course, the observations open up the other question, Is parthenogenetic development found in any other Spider ? . Hew British Acarus.f — Mr. A. H. Michael gives an account of a new genus of Tyroglyphidse from Cornwall ; it was first observed in the water-weed Cladophora fracta, and it is proposed to call it Lentungula algivorans. The great peculiarity and interest of the form are to be found in the tarsi and claws ; the tarsi of the two front pairs of legs are very powerful, and form efficient climbing organs ; the claws of the same pairs of legs are mounted on long flexible peduncles which spring from the sides of the tarsi and are capable of being flexed at the will of their possessor. Most nearly allied to Hericia , the new genus is distinguished not only by the characters already mentioned, but by the terminal position of the anus, and the absence of sexual dimorphism. Brain and Sense-Organs of Limulus.J — Hr. W. Patten deals at considerable length with the morphology and physiology of these parts of the nervous system of Limulus. Healing first with the sense-organs, he urges that we can reduce the whole system of them either to isolated sense-cells or sense-buds, or aggregations of the same. In the young, sense-buds are found in all parts of the body and are everywhere alike ; afterwards they degenerate, or they become olfactory, gustatory, or tem- perature organs; the resemblance of these buds to ommatidia is so striking that both must be included in the same category. The author next deals with the morphology of the Arthropod brain, and asserts “ that after we have torn off the deceptive Arthropod mask that disguises Limulus we discover that the nervous system, with all its complex and intricate modifications, shows, as a whole, a profound structural similarity to that of Vertebrates.” Compared with the light thrown by the King-Crab on the phylogeny of Vertebrates, Ascidians, Balanoglossus , Nemerteans, Annelids explain nothing. Dr. Patten truly says that, if the Arachnid theory of the origin of Vertebrates be true, many current views on phylogeny, ontogeny, and important problems in Comparative Anatomy are based on false conceptions and must be revised. * Abh. Zool.-Bot. Ges. Wien, xliii. (1893) pp. 204-6. f Proc. Zool. Soc. Lond., 1893, pp. 262-7 (1 pi.), t Quart. Journ. Micr. Sci., xxxv. (1893) pp. 1-96 (5 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 627 e. Crustacea. Indian Carcinology.* — Prof. J. R. Henderson’s memoir, which deals only with Decapod and Stomatopod Crustacea, contains identifications of 289 species, thirty-three of which are new ; two are regarded as the types of new genera. Several species are shown to be synonymous with others. The author gives an interesting account of the nature of the ground from which he himself has collected specimens. Large numbers were obtained by divers, who brought to the surface blocks of coral, in the crevices of which, or on the branches of which, many Crustacea are to be found. The Indian Crustacean fauna is that of the Indo-Pacifie area generally, and it is doubtful whether there is a single genus con- fined to or characteristic of India. Nearly two-thirds of the total number of species described in the present memoir are known from the seas of the Malay Archipelago ; about one-third occur near Mauritius, and about the same proportion is known from North Australia. Physiology of the Crayfish, f — M. L. Cuenot has fed Crayfishes with food stained with different anilin colours ; these show that the “ liver ” has the function of absorbing soluble bodies such as peptone and sugar, while the short mid-gut is charged with the duty of absorbing fats. The dorsal pyloric valve is found not to be a means, as Huxley and others have supposed, for preventing flow from the intestine back to the stomach ; an injection per anum is sufficient to show that the passage is free. Its function is to convey non-digested solid matters directly to the terminal intestine, which is lined by chitin, and to save from their rude contact the delicate wall of the mid-gut. So far it is comparable to the funnel found by Schneider in the intestine of many Insects. In Astacus and Maia the author has found a circular mass of spherical glands at the point where the mid- and hind-gut join ; and from these glands fine ducts open at this point. The “ liver ” of Decapod Crustacea, in addition to secreting digestive ferments and accumulating reserve-products such as glycogen and fat, plays an important part not only as a place for the absorption of the soluble products of digestion, but as a regulator of the amount of water which is contained in the blood. Embryology and Morphology of 0xyrhynchi4 — Dr. G. Cano con- tributes a welcome study of these forms, describing the segmentation, the origin of the organs, and the larval stages. We cannot do more than state a few of his general results. The Inachidse and Maiadae are hatched in a stage between zoea and metazoea — the deutozoea stage — in which the internal branch of the second antenna is well developed, and there are eight pairs of thoracic appendages. The zoea is a polymorphic coenogenetic form from which few phylo- genetic conclusions can be deduced. Purely larval modifications are such as the following ; — The diverse forms of zoea in Macrura and Brachyura, the variable reduction of the thorax associated with the loss of one or more appendages, the conformation of the second pair of * Trans. Linn. Soc. Lond., v. (1893) pp. 325-458 (5 pis.), t Comptes Rendus, cxvi. (1893) pp. 1257-60. X MT. Zool. Stat. Neapel, x. (1893) pp. 527-83 (3 pis.). 2 x 1893. 628 SUMMARY OF CURRENT RESEARCHES RELATING TO antennm in Pinnotheres and Leucosiidge, the variable development of the lateral laminae of the telson, the disappearance and subsequent re- appearance of some appendages (first maxillipede in Scyllarus ). As phylogenetic characters of the zoea may be noted the presence of the unpaired nauplius eye, the persistence of the exopodite in two or more thoracic appendages, the presence of the ganglionic chain in the abdomen of Brachyura, the distinctly bilobed mandibles in Brachyura, the presence of the mobile spine on the second antennae, and the charac- teristic form of the anal segment. The systematic relations of the Oxyrhynchi may be thus expressed : — Maiadae Partlienopidae Inachidas Latreillia Development of Maia Squinado.* — Herr F. Urbanowitz gives a preliminary account of the development of this Crab. From the ventral blastoderm small cells migrate into the vitellus, forming a transitory endoderm; a few which remain near the blastoderm form the first rudiment of midgut. Almost all the mesoderm of the nauplius is like- wise transitory, and its degeneration is briefly described. In connection with the origin of the nervous system the author notes the appearance of a pair of ganglia, to which no appendages correspond, and which may be regarded as homologous with the “ primary brain ” of Copepods. Embryology and Histogeny of the Isopoda.t — Herr Jozef Nusbaum has investigated this subject chiefly on Ligia oceanica and Oniscus murarius. With regard to the origin of the germ-layers in Ligia , the endoderm arises from an unpaired posterior median solid rudiment, the mesoderm chiefly from two paired lateral regions of the primitive three-cornered embryonic disc. The mesoderm then forms rows of cells arranged very regularly. The posterior and most important of the cell-rows are formed from the paired lateral regions, but the central rows seem to be largely formed from the endoderm. The ectoderm shows a somewhat similar arrangement in rows. The liver outgrowths and the rudimentary mesenteron are formed in a very complicated manner by the endoderm rudiment, which flattens out, becomes paired, and surrounds the yolk. The body-cavity is formed by the fusion of spaces arising between the mesoderm cells. * Biol. Centralbl., xiii. (1893) pp. 348-54. + Abh. Krakauer Akad., xxv. (1893) (6 pis.) (Polish); Biol. Centralbl., xiii. (1893) pp. 429-35. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 629 In the nervous system the ganglia become differentiated from before backwards. A notable point of difference between the thoracic and the abdominal ganglia is that, while the former arise from an originally paired rudiment, the latter are primarily unpaired. The brain is formed by the fusion of three pairs of ganglia, the suboesophageal ganglion by that of four pairs. In the abdomen there is a trace of a seventh pair of ganglia, which is of great interest in the light of the fact that a reduced seventh pair of appendages exists. From his observations on the development of the brain, the author is of opinion that the segment bearing the antennules is pre-oral ; the antennae of the insect, which are post-oral, cannot therefore be homo- logized with the antennules of the Crustaceans, but only with the first post-oral appendages, the antennae. The eyes develope towards the sides of the optic ganglia, which spread out and grow below their peripheral part. The eye-lobes at first consist of a single layer of cells which subsequently becomes several- layered. Behind this solid thickened region a deep inpitting is formed which is open above. There is, however, no optic invagination. The elements of the eye are differentiated from the layers of the thickened region. The heart arises from two sets of cardioblasts which at first lie in the yolk. The two sets are at first widely separated, but later take up a position on either side of the proctodaeum at its hinder end. They become hollowed out towards the proctodaeum, and, moving towards each other above it, they fuse to form a hollow tube. The wall then becomes divided into muscular and endothelial layers. The result of his investigations leads the author to the conclusion that the affinities of the Schizopoda to the Isopoda, and so to the Arthrostraca, are much greater than their affinities to the rest of the Thoracostraca. In both the Isopoda and the Schizopoda there is no invagination of the gastrula, and the endoderm grows round the food- yolk from without; there is no wandering of endoderm cells as in Palaemon. The embryos of the Isopoda are provided with two-forked thoracic feet, consisting of a two-jointed protopodite, a five-jointed endopodite, and an unjointed rudimentary exopodite, as well as an additional division perhaps homologous with the epipodite in Nebalia. The embryo also exhibits a rudiment of a seventh abdominal foot and ganglion, as is the case in Schizopoda. Formation of Gonads of Amphipoda.* — Miss M. Rossykaia-Kojev- nikova, finding that numerous embryologists have thrown doubt on her account of the development of the gonads of certain Amphipoda, f has examined the development of Gammarus pulex. She finds that she has been in error, and that the elements of the gonads are not detached from the hepatic sacs. Amphipoda of Saint Vaast-la-Hougue.J — MM. E. Chevreux and E. L. Bouvier give a list of sixty species from this locality ; two are new to the French fauna, six to the Channel, and four to the French side of the Channel. The new genus Perrierella is established for the * Zool. Anzeig., xvi. (1893) pp. 33-5. f See this Journal, 1889, p. 510. X Ann. Sci. Nat., xv. (1893) pp. 109-44 (1 pi.). 2x2 630 SUMMARY OF CURRENT RESEARCHES RELATING TO species which has been called erroneously Aristias tumidus and Lysianax andouinianus by different authors. Antennae of Cyclopidae.* — Prof. C. Claus shows how the prehensile 17-jointed antennae of male Cyclopidae are derived from the 10-jointed appendages of the young, and that they are referable to the type seen in the females and in Calanidae. The distal portion of the prehensile antennae of Cyclopidae has the same number cf joints as the corresponding part in Calanidae, the geniculation occurs at a similar place, there are freshwater Calanidae approximating to the Cyclopidae, the youngest Cyclopid stage of Cyclops has rudiments of the antennary exopodite and 2-jointed mandibular palps ; these and other facts corroborate a con- clusion based on a wider series of observations, that the Cyclopidae are simplified and retrogressive Copepods of the Calanid type, and that the Calanidae and Pontellidae are nearest the Protocopepoda. Herr Al. Mrazek j* has, independently, reached conclusions which are in the main similar to those of Prof. Claus, e. g. regarding the relations between Cyclopidae and Calanidae. Freshwater Harpacticidae.f — Herr Al. Mrazek gives an account of the forms which he has found in Bohemia. His investigations reveal an unsuspected abundance of species. Indeed, the family appears to have been somewhat neglected by systematists. In his general notes the author speaks of the resemblance to Harpacticidas exhibited by some species of Cyclops , e. g. C. fimbriatus, C. affinis , and C. phaleratus. This resemblance is the result of “ convergence,” i. e. of adaptation to similar conditions of life. Herr Mrazek’s systematic list is as follows : — Subfam. Longipediinae Boeck. Phyllognathopus paludosus g. et sp. n. „ Canthocamptinae Brady. Marsenobiotus vejdovskyi g. et sp. n. Epactophanes richardi g. et sp. n. Ophiocamptus g. n., two new species and 0. brevipes. Canthocamptus autt., four new species. Vermes, a. Annelida* Post-Larval Stage of Arenicola marina. § — Dr. W. B. Benham understands by “post-larval stage” that stage in the developmental history of Arenicola in which the full adult number of somites has appeared, and the body is divisible into an anterior chaetigerous region and a posterior achaetous region or tail, but in which the gills are not completely formed or have not made their appearance. The larvae, as obtained by Mr. Garstang, were found to be each inhabiting a per- fectly colourless and transparent gelatinous tube, obviously secreted by itself. This tube seemed to invest the body closely, and was cer- tainly no impediment to the animal. Each segment of the tail was found to be surrounded by a band of gland-cells, and these cells were in a * Zool. Anzeig., xvi. (1893) pp. 277-85. t Tom. cit., pp. 285-9. X Zool. Jahrb. (Abth. Syst., &c.), vii. (1893) pp. 89-130 (4 pis.). § Journ. Mar. Biol. Ass., iii. (1893) pp. 48-53 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 631 double row in the anterior somites. The presence of a closely investing gelatinous tube, taken in connection with certain internal characters, seems to point to an affinity between Arenicola and the Chlorhaemidae. Wiren has described in adult specimens a continuous perienteric sinus ; this is not to be found at the larval stage. In this fact the author finds a support for the view he has already propounded that it is improbable that the perienteric sinus of certain earthworms is, as some have held, a primitive feature. In Arenicola , at any rate, the sinus of the adult is preceded by a network. In the body-wall the sub- epidermic tissue described by Wiren has not yet made its appearance. In place of the great wide nephridial sac of the adult there is, in the post-larval stage, quite a simple narrow tube ; this runs nearly in a straight line from the nephridiopore to the nephrostome ; this last seems to be perfectly simple, and as it has no lips we cannot speak of a funnel in the usual sense of the word. The alimentary tract has the same regions as in the adult. Polychaeta of North Carolina.* — Dr. E. A. Andrews gives a list of 57 Polychaetes from Beaufort, N.C., but he is convinced that this gives no real idea of the richness of the fauna. Harmothoe aculeata is a new species, but is a common form. Accetes lupina Stimpson forms peculiar tubes which call to mind those of Cerianthus. Procersea tardigrada Webster seems to be a Syllid in which there is a strong tendency to the acquirement of a regular metameric marking ; this does not, however, coincide with the metamerism of the somites, but tends to follow a special law. Eunice ornata sp. n. is found not uncommonly in Sponges. Dio- patra cuprea A. & E. is obviously in the habit of reproducing its anterior or posterior end, and this appears to be almost a necessity from the worm’s custom of protruding itself from its tube. D. magna sp. n., is one of the largest Annelids on the East American coast. Ophelina agilis sp. n. is common; Polydora commensalis sp. n. was found in 50 per cent, of all the Ilyanassa- shells inhabited by the small Hermit Crab, Eupagurus longicarpus , and overgrown by colonies of Hy dr actinia. Axiothea mucosa sp. n. is one of the most abundant Annelids found at Beaufort; it forms a Y-shaped tube, one arm of which is closed at its end by the egg-mass, while the other gives the Annelid access to the water. Though placed in Quatrefages’ genus Petaloproctus, P. socialis sp. n. would probably better find a place in a new genus ; it is a common form which constructs thick coarse tubes of sand, often cemented together in groups and convoluted a few inches below the surface of the sand. Ammochares sedijicator sp. n. is not uncommon in areas where they are scarcely uncovered by the tide ; the excrement is dis- charged in the form of cylindrical masses, half the length of the body, and composed of excessively fine sand held together by mucus. Loimia turgida sp. n. is found under stones along the shore. Four of the other species enumerated are new to America. Various larval forms were also observed. Polychaeta from Deep Water off Ireland.! — Miss F. Buchanan has a note on the deep-water Polychaetes collected during the Royal Dublin * Proc. U S. Nat. Mus., xiv. (1892) pp. 277-302 (7 pis.). t Sci. Proc. Roy. Dublin Soc., viii. (1893) pp. 167-79 (1 pi.). 632 SUMMARY OF CURRENT RESEARCHES RELATING TO Society’s survey off the west coast of Ireland. Only seven species were obtained, one of which, Eunice philocorallia , is new, and one, Lsetmonice produda Grube, has only hitherto been recorded from Kerguelen. This last, however, is represented in the collection of the British Museum by a specimen from Japan. The Irish specimens are from the greatest depth, and, perhaps therefore, are distinguished by the absence of eyes. Notes are given to clear up the confusion which exists between Lsetmonice filicomis Kbg. and L. Kinbergi Baird. Eunice philocorallia presents a good many individual variations ; it occurred abundantly in parchment- like tubes in colonies of Lopliohelia proligera ; it appears to be most nearly allied to E. floridana of Ehlers. Micronereis variegata.*— M. E. G. Racovitza has discovered the male of this Annelid, which has not been detected by previous observers ; it is much smaller than the female, and has a smaller number of feet ; on the third pair of feet it has also special hooks which are not found in the female, and there are differences in the form of the jaws which are fully explained. The hooks have a copulatory function, and by them the male attaches himself to the female, and may remain in position for three days. The female becomes quite altered in appearance after oviposition, and the modifications which occur are explained by the con- tinual movement of the animal through the very thick glairy mass which surrounds the eggs. Variations in Genitalia of British Earthworms. f — Mr. M. F. Woodward, continuing his researches on this subject, finds that the presence of additional pairs of gonads is by no means of rare occurrence ; fifty worms belonging to five species, and taken at hazard, were found, in fourteen cases, to have additional gonads. In one case, a true hermaphro- dite gland was, for the first time, observed in Chaetopods. The author is of opinion that some of the facts he has noted “ accentuate the belief in the inherent power of the entire coelomic epithelium and their derivatives to produce sex-cells.” It seems probable that the varying distribution of the gonads in the OligochaBta is the outcome of irregular abbreviation of some diffuse and possibly hermaphroditic condition under perfected segmentation, rather than of a condition in which the gonads were already restricted to definitely metamerically arranged centres as in the Planarians. Anatomy of Ocnerodrilus.J — Mr. G. Eisen gives an anatomical account of new species of this genus, eight being here diagnosed. He gives reasons for disagreeing with Mr. Beddard in regarding Gordiodrilus as one of the Ocnerodrilidae, and proposes to form for it a new family Gordiodrilidae ; concise definitions are given of both families, and it is urged that they connect the limicolid Oligochaeta with the higher terrestrial forms. Anatomy of Kerria.§ — Mr. G. Eisen’ describes two new species of this genus, somewhat lately established by Mr. Beddard ; the author cannot accept the view of its affinity to Acanthodrilus , owing to the * Comptes Rendus, cxvi. (1893) pp. 1390-2. t Proc. Zool. Soc. Lond., 1893, pp. 319-24 (1 pi.). X Proc. Calif. Acad. Sci., iii. (1893) pp. 228-99 (6 pis.). § Tom. cit., pp. 291-318 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 633 presence in the latter of blood-vessels on the nephridia. He thinks Kerria , Ocnerodrilus , Gordiodrilus , and Pygmseodrilus form one large group, though they should not all be placed in one family. Earthworms of the Neighbourhood of Berlin.* — Herr A. Collin reports that, of the eighteen species of Lumbricids known from North Germany, thirteen have been found in Berlin ; one, Criodrilus , has no other known German locality than Breslau. Anatomy of Sipunculus.j' — Mr. A. E. Shipley, in some notes on the anatomy of this Gephyrean, describes, inter alia, the projections in the brain. They are solid, and consist of a number of connective-tissue cells. They are rather richly supplied with nerve-fibres. Beyond this last fact there is nothing in their structure to suggest that they are sensory organs, and the author is quite unable to surmise what their function may be. Mr. Shipley had been wont to consider that the rectal diverti- cula of Sipunculus were homologous with the anal caeca of Bonellia. Close study, however, reveals a number of differences ; they do not open into the coelom ; they have no ciliated funnels at their free ends ; nor do they open into the lumen of the intestine, but into a well-developed system of lacunar spaces in the wall of the rectum. It is possible that these glands have somewhat the same functions as the lymphatics and the numerous glands which in all classes of animals exercise some influence on the constituents of the circulating medium. B- Nemathelminthes. Bradynema rigidum.f— Dr. 0. zur Strassen has made a detailed study of this Nematode, which is parasitic in the body-cavity of Aphodius fimetarius, one of the Scarabaeidte. Yon Siebold, who discovered it, called it Filaria rigida, and Moniez erroneously referred it to the nearly related genus Allantonema. It requires, however, a new genus Brady- nema. The parasite lives freely within its host ; from two or three to twenty may occur together; they apparently do little injury. The adult female is at once recognizable as a Nematode ; the body measures 3-5^ mm. in length by • 15- *27 mm. in breadth ; there is no mouth nor anus nor excretory pore, but a conical elevation bearing the vulva marks the posterior end. In its movements Bradynema is exceedingly sluggish, and the musculature is extremely reduced. Most of the interior is occupied by the broad tubular uterus, parallel to which lie the ovary and the oviduct. There is a clear receptaculum seminis where the oviduct enters the uterus. The body- wall has a meshed structure which encroaches at both ends on the body-cavity. In the development, which is described at great length, the follow- ing points may be noted. The prostoma persists and is always recog- nizable at least internally. In the same region a porus excretorius is formed. The ectoderm is a simple, never thickened sheath. A mouth- cavity is represented by a shallow depression at the anterior end. The mesoderm forms two lateral and one ventral longitudinal band, which unite anteriorly and posteriorly. Stomodaeum and proctodaeum are formed from mesodermic tissue. The rudiment of the gonad consists of * SB. Ges. Naturf. Freunde Berlin, 1892, pp. 115 and 6. t Proc. Zool. Soc. Lond., 1893, pp. 326-33 (3 pis). X Zeitschr. f. wiss. Zool., liv. (1892) pp. 655-747 (5 pis.). 634 SUMMARY OF CURRENT RESEARCHES RELATING TO one germ-cell and two terminal cells. Some of the author’s results distinctly corroborate the theory of Hallez that the Nematode larva is referable to the Trochophore type, but he is inclined to suspect that the late mesodermic formation of the Nematode anus points to derivation from Hatschek’s Protrochula. As to the sexual relations of Bradynema , the author comes to the interesting conclusion that the male larvae are protandric hermaphro- dites, which subsequently become the adult female parasites, and that the female larvae have really not to do with the continuance of the species. Development of Pseudalius inflexns.* — Herr Th. List finds that, in this form, the first segmentation-plane of the ovum is not in the middle line, so that the blastomeres are of unequal size. The smaller forms the ectoderm, the larger the endoderm. In the twelve-cell stage the cell-plate is distinctly two-layered, consisting of an eight-celled dorsal ectoderm and a four-celled ventral endoderm. As cell-division goes on, an amphiblastula is formed with a distinct blastula cavity. The ecto- derm cells continue to increase very rapidly, so that the amphiblastula becomes a flat two-layered plate which forms a gastrula by epibole. The prostoma, which is at first a longitudinal slit, closes from behind forwards, leaving for some time a rounded opening at the anterior end. Two primitive mesoblasts appear at the sixteen-cell stage, having originated from the ectoderm. They give rise to long rows of meso- blastic cells which, in cross section, form a ring round the intestine, the ventral rows being the latest formed. Later, by the close connection of mesoderm and ectoderm cells, a homocoele is formed, which secondarily becomes schizocoelic. The nervous system arises, towards the end of gastrulation, from the upper thickened region of the ectoderm. The mouth and anus are formed as secondary invaginations after the closure of the prostoma. Trichinosis.f — The occurrence of what appears to be the first case of an epidemic of trichinosis in Belgium led Dr. P. Cerfontaine to a research on this subject. He finds that, during the first two periods the cysts are destroyed in the stomach, in which the larval Trichinae either live for some time, or they pass at once into the small intestine. In the intestine they grow, and fecundation is effected on and after the second day of infection ; the males, after a stay of varying length in the intes- tine, are expelled with the faeces. In the female the development of the larvae commences immediately after fertilization. The embryos begin to be set free about the sixth day of infection. A certain number of the females penetrate into the wall of the intestine, and even into the mesentery ; these have more chance of infesting the organism than those which remain in the intestinal canal, since their embryos cannot be expelled with the faeces. It is probably by means of the lymphatic systems that the parasites first make their way into the tissues of their host. The fact that adult Trichinae penetrate the tissues gives an explanation of the violence of the gastro-intestinal troubles which often characterize the beginning of the malady. * Biol. Centralbl., xiii. (1893) pp. 312-3 (1 fig.). t Bull. Acad. Koy. Belg., lxiii. (1893) pp. 461-88 (1 pi.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 635 New Heterakis.* — Dr. Magalhaes describes a new species of Hete- rdkis from the domestic fowl, which he calls H. brasiliensis, and he points out the differences between it and the four species of the same genus which are already known to live in Gallus gallinaceus . y. Platyhelminthes. Nemertines of Plymouth Sound.* — Mr. T. H. Riches enumerates thirty-three species of these worms from Pymouth Sound. Of these, four are new, viz. Tetrastemma nigrum , T. immutabile , T. ambiguum, and Amphiporus dissimulans ; Nemertes Candida is new to Great Britain; Carinella polymorpha and Micrura aurantiaca have not been previously recorded north of the island of Herm, and DrepanopJiorus rubrostriatus has not till now been recorded north of Guernsey. Although the Nemertines exhibit brilliant colours, and although many are conspicuously marked, the author has not been able to find any very definite relation to the surroundings. Varieties have been obtained which in many respects connect such well-marked species as Tetrastemma candidum, T. vermiculatum , and T. melanocephalum. The author adopts Burger’s classification into the orders Protonemertini, Mesonemertini, Metanemertini, and Heteronemertini. With regard to the spawning periods it may be stated generally that, during the whole year some one or more species are breeding, and a large number of species were found with ripe generative products from late summer to the middle of December, when the author left Plymouth. CephalotJirix bioculata has been successfully bred in captivity, and it is hoped that an account of its development will shortly be published. A very interesting description is given of the variations of Tetrastemma candidum , of which we may particularly note one that only differed from the reddish variety of the species with regard to the anterior pair of eyes ; these, instead of being compact and round, were broken up into two little masses of minute specks, invisible except under the Micro- scope. A case in which a relation could be detected between the colour of the animal and that of its surroundings was afforded by T. melano- cephalum, a specimen of which, found among red weeds, was coloured by minute red-brown pigment-granules. Turbellaria of Plymouth Sound.}; — Mr. F. W. Gamble, who has lately published a memoir on British Marine Turbellaria, § now gives a list of the species found in the neighbourhood of Plymouth. He had here to do with a practically unworked field. About 18 per cent, of the species found are known to occur in the Mediterranean. Of the fifty-six species but few are new, and several are known to occur in Scandinavian waters. Specimens were obtained by collecting sea- weeds and placing them in vessels of sea-water ; thence the Rhabdocoeles emerged in great numbers, especially towards night, and could be picked out with a pipette ; another way is to use a hand-net, in the mouth of which a sieve is placed to prevent the entrance of bulky weeds; the dredge also brought up a large number of interesting forms, and examination of the dredge- * Bull. Soc. Zool. France, xvii. (1892) pp. 219-21 (1 fig.). t Journ. Mar. Biol. Ass., iii. (1893) pp. 1-29. J Tom. cit., pp. 30-47. § See this Journal, ante , p. 479. 636 SUMMARY OF CURRENT RESEARCHES RELATING TO material at night gives a vivid idea of the activity and voracity of this group of worms. The classification of zones adopted by the author is regarded as purely tentative, and we still require much information as to the vertical distribution of Turbellaria. Mechanism of Stinging Cells in Turbellaria.* * * § — M. E. Penard has studied this subject in the Turbellarian Stenostomum. After point- ing out the insufficiency of current explanations of the mechanism by which the thread is discharged, he gives an account of his own observations and inferences. The stinging cells are ovoid, surrounded by a firm membrane, which at the anterior pole thins suddenly, so as to form a delicate pellicle closing the cell. The cell contains a nucleus imbedded in protoplasm, and also an inner capsule attached to the anterior end of the cell, and containing the spirally coiled thread. Also within the capsule are three processes radiating from the closing mem- brane, and surrounding the coil thread. When discharge is about to take place, the plasma of the cell becomes turgescent, and so exerts pressure on the internal capsule. The three rigid processes form a pyramidal cage around the thread, and so keep it in position until the pressure becomes too great for the closing membrane. This yields, the apposed points of the processes divaricate suddenly and widely, while their other ends remain attached to the evaginated capsule. By this means the thread is launched forth explosively, and is at the same time uncoiled through all its length. Eew European Land Planarian.j — Under the name of Bhyncho- demus pyrenaicus Prof. L. Graff gives an account of a new species of Land Planarian taken near St. Jean de Luz. The single specimen measured 53 mm., so that it was of considerable size. The integument is of a honey-yellow colour, except on the ventral side ; this last has a reddish-violet median part with the sides yellowish-grey. The species is declared by Dr. Simroth, who has described two Land Planarians from Portugal, to be unknown to him. Swedish Tricladidse.J — Herr D. Bergendal describes Gunda Ulvse , Uteriporus vulgaris, Dendrocoelum lacteum , Z). punctatum, Planaria torva , Pl. lugubris, PL polychroa, and the genus Polycelis. He has some notes on classification, and recognizes two families — Uteriporid® and Plana- riidse, the latter with Planari®, Polycelid®, and Gundid® as sub- families. Structure of Trematodes.§— Herr E. Walter has studied Monostomum trigonoceplialum Rud., M. reticulare van Ben., M. proteus Brandes, para- sites of Chelone viridis. After describing these species separately, he discusses some moot points in regard to the minute structure of Trematodes. To three of these we shall briefly refer. First, in regard to the parenchyma, Herr Walter distinguishes four types : — (1) In the most primitive state the parenchyma consists of a homo- geneous or finely granular substance in which nuclei are imbedded without distinct cell-boundaries, e. g. Distomum reticulatum. * Arch. Sci. Phys. et Nat., xxix. (1893) pp. 487-94 (5 figs.), f Bull. Soc. Zool. France, xviii. (1893) pp. 122 and 3. j Ofversigt K. Vetensk.-Akad. Forhandl., xlix. (1892) pp. 539-57. § Zeitschr. f. wiss. Zool., lvi. (1893) pp. 189-235 (3 pis., 1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 637 (2) Within the cell-plasma, between the nuclei, intracellular vacuoles of different sizes appear, and cell-boundaries are indistinct, e. g. Mono- stomum trigonocepJialum. (3) The vacuoles are so large that the protoplasm forms only a sheath of the cell, and the elements form a connected meshwork in which each mesh represents a cell, e. g. Mon. reticulare. (4) The vacuoles may fuse, and the cortical sheath is burst and torn at intervals, e. g. Mon. proteus. The most important modifying factor is the formation of vacuoles, and it must be noticed that different types may occur in tbe same species at different ages and times, or at different parts of the body. The accumulation of water in the vacuoles probably brings about turgescence of cells and tension of the skin, and thus facilitates loco- motion. Secondly, as to the cuticle, which serves for the insertion of the parenchyma muscles, Herr Walter regards it as a product of the subjacent subcuticula, and that again as a product of the chromato- philous subcuticula cells. Thirdly, as to the so-called “ large cells ” of Trematodes, often regarded as ganglionic, they are also derived from the chromatophilous cells, and are merely stages in transition towards parenchyma. Body-parenchyma of Trematodes.* * * § — Herr A. Looss finds that this tissue, apart from what may be deposited within it, is originally formed of entirely homogeneous cells. In the adult state the firm and thick membranes of these cells persist, closely appressed, cemented by inter- cellular substance, forming a meshwork with colourless plasmic fluid in the meshes. The subcutaneous stratum of indifferent cells corresponds anatomically and physiologically to the cambium in plants. As to the skin, the -author regards it as a secreted product, and is inclined to derive it for the most part from the body-parenchyma. Trematodes of Reptiles and Amphibians.t — Dr. P. Sonsino gives a list, with some descriptions, of these parasites. Thus, in Emys lutraria there is Polystomum ocellatum , in Chelone caretta four species of Distomum , e. g. D. cymbiforme , in the chamaeleon three doubtful species of Distomum , in the edible frog Amphistomum subclavatum , Distomum vitellilobum , D. ovocaudatum , D. clavigerum, D. cygnoides, D. endolobum , D. variegatum , CodonocepJialus mutabilis , and so forth. The predominant Taenia of Rome.J — Dr. G. Alessandrini asks what species of Taenia predominates in Rome and the surrounding province, and answers that it is T. mediocanellata or saginata. But none seems very abundant. Brazilian Helminthology.§— Dr. P. S. de Magalhaes, in his first note, gives a description of Linstow’s species Taenia cuneata , from the duodenum of the Fowl. There are certain differences, however, in the two descriptions, but these the author ascribes to variations in the length * Ber. K. Sachs. Ges. Leipzig, 1893, pp. 10-34. t Atti Soc. Tosc. Sci. Nat., viii. (1893) pp. 183-90. x Boll. Soc. Bom. Stud. Zool., ii. (1893) pp. 83-6. § Bull. Soc. Zool. France, xvii. (1892) pp. 145 and 6. 638 SUMMARY OF CURRENT RESEARCHES RELATING TO of the hooks and the form of the suckers, which are frequent in the Taeniidse. The intermediate host is also different, for Grassi and Rovelli have shown that, in Sicily, Tsenia cuneata has as such Alolobo- phora fcetida, which is not found in Brazil. Notes on Cestodes.* — Dr. C. W. Stiles has a short note on Tsenia giardi, a species which has been the subject of some discussion as to its genital pores. The author states that they are generally alternate, as Rivolta and Neumann assert ; at the same time, it is not rare to find segments with double genital pores, as described by Blanchard and Moniez. It often happens that quite a series of female organs are found developed on one side of a segment, while on the opposite side there are rudimentary female organs. As Tsenia {M.oniezia') expansa is at present so diagnosed as to include two, if not three, distinct species found in Sheep and Oxen, Dr. Stiles has made an examination of some of the segments of the original example of Rudolphi. In them there are to be found near the posterior edge rounded organs, much larger than testes (with which, perhaps, they had been confounded) ; these are small caeca which arise from the boundary between two successive rings, and project into the parenchyma of the anterior ring. The sac is hounded by an invagination of the cuticle of the worm, which is surrounded by a, possibly, glandular tissue, which stains very deeply. The author gives a short notice of an allied species, which he proposes to call Moniezia ( Tsenia ) planissima. 5. Incertse Sedis. Philodinidae.t — Dr. 0. Janson gives a very useful and valuable summary of our present knowledge of this difficult family, including the result of his own researches. The essay consists of three parts : — Part i. deals with the anatomy, part ii. with the biology or habits, and part iii. with the classification of the Philodinidee, giving at the same time a complete diagnosis of every recognized species, fifty -two in all. Some previously described species are excluded as not sufficiently known, and the following six species are described as new : — Callidina longirostris , C. vorax , C. EJirenbergii , Adineta tuberculosa , A. barbata , and A. gracilis . In the anatomical part Dr. Janson maintains Dr. Plate’s view that the Philodinidse have no separate contractile vesicle, but that the two lateral canals coalesce and form a short single tube which then enters the posterior part of the intestine or cloaca, which itself is contractile and contracts regularly. With regard to the function of the contractile vesicle in Rotifers the author agrees with Cosmovici,| who has stated his belief that the character of the contractile vesicle has hitherto been misunderstood, and that anatomically it is nothing but a cloaca having the function of driving out the water which has passed through the digestive tube, and not of expelling excretions from the perivisceral fluid. It must be stated, however, that while plausible enough in the case of the Pliilodinidae, this view utterly breaks down when other * Bull. Soc. Zool. France, xvii. ("1892) pp. 157-9. f “ Versuch einer Uebersicht iiber die Rotatorien-Familie der Philodinaeen,” von Dr. Otto Janson, Abhandl. des Naturw. Yer. Bremen, xii. (1893). Also printed separately, Marburg, 1893, 85 pp., 5 pis. % This Journal, 1888, p. 955. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 639 Rotifers are taken into consideration, such as the Asplanchnidae, where the large contractile vesicle has obviously no connection whatever with the blind digestive tract. Dr. Janson has been so fortunate as to discover for the first time some winter eggs in several species of Callidina, and as these so-called winter eggs in other rotifers have been proved to be the result of fecundation, it becomes probable that a male exists, although no male Philodina has yet been found. The question of how the mature young and eggs leave the parent in the apparent absence of a uterus and oviduct is left much as it stood before. The young of viviparous Philodinidse lie freely in the body- cavity of the parent, and break forcibly either through the wall of the cloaca or through the body-wall, generally at a point near the cloaca — an operation which generally causes the death of the mother. Three such acts have been seen by the author. The extrusion of an egg has not yet been witnessed by any observer, and it is still a mystery how it leaves the body-cavity of the parent, in which it appears to lie freely. Here is an interesting point left for future observers. Euchlanis bicarinata Perty.— Mr. F. R. Dixon-Nuttall contributes the following note: — “ I found this rotifer on 7th April, 1893, in some water sent to me by Mr. J. Hood, of Dundee. This rotifer is described as a Euchlanis , in Hudson and Gosse’s ‘ Sup- plement to the Rotifera,’ p. 40, pi. xxxiii. fig. 31, but it is undoubtedly a Salpina, as the lorica is a true form of that species ; that is, all of one piece, and split on the dorsal surface. The lorica viewed from the posterior, fig. 89,A may be called four- cornered ; there is a keel-like ridge on the ventral surface. It has the power, like most Salpinse, to cause the dorsal split to gape or almost close up, though the normal size of the cavity is as shown in fig. 89A One of the most striking points of this animal is the length of the lower joint of the foot, which is of itself about one-third the length of the lorica. The descrip- tion given, as above mentioned, speaks of a short joint at the base of the two toes. There is no such joint, the toes come direct from the base of the “long joint.’’ There is what might be called a “ cup-and-ball ” joint, where this long portion of the foot joins that part nearest the body. The toes are blade-shaped, and a little longer than half the length of the long joint of foot. The eye is elongated, and rests on the under part of the brain close to the mastax. There is a dorsal antenna, as seen in fig. 90* Though this little animal is exceedingly restless, gliding quickly over anything it comes to, bounding first to one side and then to another, it is a very slow free swimmer. The length of the lorica is 1/100 to 1/95 in. ' Fig. 89.a 610 SUMMARY OF CURRENT RESEARCHES RELATING TO Whenever this rotifer is placed in its genus it will have to be re- named, as there already is Salpina bicarinata — see Sup. Hudson and Gosse, p. 38, pi. xxxiii. fig. 30.” Fig. 90.a Rotifer without “Rotating Organ.” *— Prof. A. Wierzejski has discovered near Krakau a remarkable rotifer, which he names Atrochus tentaculatus g. et sp. n. The body is soft-skinned, without true segments ; its anterior end is a broad funnel, with a wide central mouth, which is surrounded by a five-lobed wreath of hollow, conical tentacles. A ciliated apparatus is entirely absent, as is the foot, the latter being repre- sented by a cupola-like, retractile, terminal joint, on which the cloaca opens. The body is covered by a layer of mud. On the gut there is a crop, and behind this a gizzard, with strong masticating organs. The gonads consist of ovary and uterus ; the young are born viviparously ; the male is unknown. The maximum length of the animal is 1*415 mm. The food consists of unicellular algae. This new type seems to come nearest to Acyclus inquietus Leidy and Apsilus lentiformis Metschnikoff, aberrant Flosculariidae. New Floscularia.f — Prof. A. Wierzejski has a preliminary notice of Floscularia atrochoides, a Rotifer which unites the essential characters of a true Floscularia with those of the author’s lately described Atrochus tentaculatus. In habits it calls to mind F. uniloba , but it has no gelatinous investment ; in the contracted stage it is so like Atrochus that it might easily be mistaken for it. From all the known species of its genus it is distinguished by its free mode of life. The structure of the internal organs agrees almost exactly with that of Atrochus , but the masticatory organs have the unci broad and bidentate. A diverticulum corresponding to the contractile vesicle of other Rotifers * Zeitschr. f. wiss. Zool., Iv. (1893) pp. 696-712 (1 pi.), t Zool. Anzeig., xvi. (1893) pp. 312-4 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 641 was, in all specimens examined, found to be full of Bacteria. The young are fully formed before they leave the mother. The chief food of this new species appears to be Algae. When fully extended it measures 1*4 mm. in length, the corona is 0*2 broad, and the body about 0*18 mm. The species, which appears to be rare, was found near Cracow. Construction of Lorica of Brachionus.* — Mr. V. Gunson Thorpo concludes that the so-called dorsal surface of the lorica really consists of two plates — a “ dorsal ” and “ basal ” — and not of one antero-posteriorly curved plate, as is generally said. He directs attention to various cases, of which we may cite that of Brachionus from Colombo, in which the dorsal plate was distinctly prolonged, though to the very slightest extent, while the basal plate was well defined. The author thinks that the dorsal plate could not be so prolonged unless it and the basal were separately developed. Echinoderma. Excretory Organ of Sea-TJr chins. t — Herr F. Leipoldt describes the much- discussed “ dorsal organ,” which extends between the lantern and the madreporic plate of sea-urchins, and which many credit with an excretory function. The author’s researches refer to Sphserechinus granu- lans and Dorocidaris papillata , especially to the former. “ One thing may be stated with certainty, that the organ is no ‘ gland/ above all. no ‘ kidney/ as P. and F. Sarasin maintain.” For there is no glandular epithelium, and no connection between the cavity of the organ and the body-cavity. Moreover, the author agrees with Leydig, that in stone- canal and madreporite the current is wholly inwards. The pigment masses, regarded by Hamann as evidences of an excretory function, seem to result from unusable or injurious substances which the wandering cells carry, and they occur in many other parts of the body. Nor are Kowalevsky’s experimental results accepted in proof of an excretory function. With Prouho, the author regards the dorsal organ as an area for the production of the amoeboid cells of the perivisceral fluid. Echinoderm Sperniatogenesis.f — Hr. G. W. Field gives a preliminary account of his comparative study of spermatogenesis in this group. He finds throughout a very general similarity, but considerable variation in minor details. The spermatogonia divide by mitosis to produce two spermatocytes, each of these again divides by mitosis to form two spermatids which, without further division, are directly changed into spermatozoa. In the nucleus alike of spermatogonium and spermatocyte, besides chromatin and karyoplasma, minute granules are found which seem to form the mitotic spindle. In the spermatid, on the other hand, similar granules are found not in the nucleus but in the cytoplasm. During the conversion of the spermatid into the spermatozoon the cell- membrane of the former becomes tightly drawn over the head of the spermatozoon, and as a mechanical consequence, according to the author, the granules fuse together to form a single large body, the Nebenkern. * Journ. Quek. Micr. Club, v. (1893) pp. 229-31 (6 figs.). f Zeitschr. f. wiss. Zool., lv. (1893) pp. 585-623 (2 pis.). X Anat. Anzeig., viii. (1893) pp. 487-93. 642 SUMMARY OF CURRENT RESEARCHES RELATING TO In the spermatozoon a centrosome is present which can be traced from the mitosis of the spermatocyte, and ultimately becomes the sperm- centrosome of the fertilized egg. It is directly derived from the original centrosome of the spermatogonium, and as it takes part in ihe mitotic processes is probably one-fourth of this centrosome. In the mature spermatozoon the nucleus, centrosome, and Nebenkern are enclosed in a delicate cell-membrane, which is apparently the per- sistent cell- membrane of the spermatid. Synonymy of Starfishes.* — Sig. P. Marchisio maintains that Ludwig is in error in placing Echinaster Dorise and Ech. tribulus as synonymous with Asterias tenuispina. Of the two first forms he gives a careful descrip- tion ; neither has anything to do with A. tenuispina ; but whether they are distinct enough from one another to be regarded as separate species is left an open question. De-Filippi has distinguished Astropecten aster as a new species separable from Ast. squamatus Muller and Troschel ; Ludwig has declared the two to be identical, and Marchisio, after a careful study of De-Filippi’s type specimens, comes to the same conclusion. Odontaster and Allied Genera, f — Prof. F. Jeffrey Bell gives reasons for uniting with Yerrill’s genus Odontaster , the Gnathaster of Mr. Sladen and the Asterodon of Prof. Perrier. The last-named authority places the genus with the Archasteridae, Mr. Sladen with the Pentagon asteridae ; Prof. Bell agrees with Prof. Perrier. A list of the species of Odontaster with synonymy and a few critical notes are added. CidarisI cnrvatispinis.j: — Under this name Prof. F. Jeffrey Bell gives a description of a remarkable new species of Cidaris from Mauritius. As the name implies, many of the spines are curved, instead of being straight, and a number are of great length. So far as can be judged from a single specimen, the new species belongs to the Dorocidaris- divi- sion of the genus. Ccelentera. Catalogue of Madreporarian Corals.§ — The part before us is entitled volume i., but it has the melancholy interest of being the only part which will be issued by the same author. Three preliminary papers by its author, Mr. George Brook, will have prepared the student for the publication of this handsome quarto volume, the photographs in which were, at considerable pains, taken by the author himself. An intro- ductory essay deals with the history of the genus Madrepora , its mor- phology, and the principles of classification. Up to the time of its publication about 170 species had been more or less completely described; of these a complete revision has been made, the chief museums of Europe having been visited for the purpose of consulting original specimens. These species have been reduced to 130, but to these there have been added 91, of two-thirds of which preliminary diagnoses have already appeared. * Boll. Mus. Zool. Univ. Torino, viii. (1893) No. 149, pp. 1-6 (1 fig.). t Proc. Zool. Soc. Lond., xiii. (1893) pp. 303 and 4 (1 pi.). J Trans. Zool. Soc. Lond., xiii. (1893) pp. 303 and 4 (1 pi.). § ‘ Catalogue of the Madreporarian Corals in the British Museum. I. The Genus Madrepora.’ 4to, London, 1893, xi. and 212 pp., 35 photo, plates. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 643 Septal Musculature and the (Esophageal Grooves in Anthozoa.*— Herr O. Carlgren finds that Cerianthus Lloydii, G. membranaccus, and C solitarius bear longitudinal muscles on the side of the septa turned away from the directive pair, and transverse muscles on the side turned towards the directive pair. It seems that the Ceriantheae possess an anterior or dorsal (not ventral) oesophageal groove, while that of the Alcyonaria and Zoanthese is posterior or ventral. Of the two grooves in Edwardske and in most Hexactinia, the dorsal corresponds to an anterior and the ventral to a posterior. Brood-chambers in Actinise.t — Herr 0. Carlgren finds two types of brood-chamber. In one type the brood-chamber is formed from the gastrovascular chambers, or from the gastrovascular space itself (in an unnamed Paractid and Bunodid). In the other type there are in the lower part of the body-wall special cavities — -invaginations of the ectoderm — in which the embryos complete their post - embryonic development. Comparative Embryology of Scyphomedusse.J — Hr. A. Goette finds that Aurelia , Cotylorhiza , and Pelagia differ in their development only in degree. All three exhibit in their youngest larvss the essential struc- ture of Scyphomedusse, differing only in the degree of completeness with which the typical features are retained. The author begins with a description of the larvae of Cotylorhiza tuberculata. These exhibit an ectodermic oesophagus, four gastric pouches, and, indeed, all the essential characters of AwreZm-larvae. The oesophageal ectoderm extends to a portion of the gastric pouches, and over the four gastric folds. In Cotylorhiza there are four true septal funnels before the proboscis is developed. In Pelagia the mouth of the larva is to be found at the invagination- opening of the ectodermic gullet, and the prostoma at the base of the closed gullet, where the communication with the central stomach is formed. The ectodermic gullet forms the principal median portion of the gut ; the central stomach and the gastric pouches are alone endodermic. The tetrad segmentation defined by the first four gastric pouches is in entire agreement with the symmetry of Cotylo- rhiza. We cannot follow Goette through his account of the develop- ment, but his conclusion is that the larvae of Pelagia possess before the beginning of Ephyra-formation the most essential features of a scyphostoma. Early Stage of Distichopora violacea.§ — Dr. S. J. Hickson gives an account of the early stages in the development of Distichopora violacea . The result is the generalization that in the Stylasteridae there is no seg- mentation, no process of invagination to form the endoderm, and no process that can be compared with ordinary primary delamination. The author next discusses the formation of the germinal layers in the Coelentera generally, and gives the following plan : — * Ofversigt K. Vet. Akad. Forhandl. Stockholm, 1893, pp. 239-47 (2 figs.). t Tom. cit., pp. 231-8 (5 figs.). j Zeitschr. f. wiss. Zool., lv. (1893) pp. 645-95 (4 pis.). § Quart. Journ. Micr. Sci., xxxv. (1893) pp. 129-58 (1 pi.). 1893. 2 Y 644 SUMMARY OF CURRENT RESEARCHES RELATING TO A. Gastrula formed by invagination of large segmentation cavity : e. g. Cotylorhiza, Pelagia noctiluca , and Nausithoe. a. Intermediate form between types A and B are found in Aurelia flavidula , in which the clump of cells that are invaginated is at first solid, and in Cyaneea capillata , in which this clump re- mains solid longer than in A. flavidula. B. A solid planula (sterrula) formed by hypotropous immigration of cells into a large segmentation cavity : e. g. Clytia , Tiara , Obelia , Cyansea arctica , &c. Intermediate forms in which the migration takes place mainly at the hind end occur in Mitrocoma. C. Sterrula formed by polypolar immigration of cells into a large segmentation cavity : AEginopsis. D. Planula formed by primary delamination ; a large segmentation cavity : e. g. Geryonia. d. There are numerous intermediate forms in which the segmenta- tion cavity is small. E. Sterrula formed by precocious delamination ; no segmentation- cavity : e. g. Aglaura , Eudendrium, &c. e. Intermediate forms have the segmentation at first incomplete : e. g. Benilla and Gorgonia. F. A multinucleated plasmodium ; no segmentation, and no segmen- tation cavity : Millepora, Stylasteridae. Dr. Hickson suggests that there is now much evidence to support the view that considerable phylogenetic significance is to be ascribed to the plasmodium stage ; he urges that too much weight has been given to the presence or absence of yolk, and that we should not expect that, when an ovum segments, it is simply repeating an ancestral phase, and that when it does not segment it is prevented from doing so by the physical ob- struction of yolk. In conclusion the author discusses the fragmentation of the oosperm nucleus ; the general results at which he arrives are : — (1) Fragmenta- tion of the nucleus is a normal method of nuclear division, and is not always a sign of pathological change. (2) In many cases in which the nucleus is supposed to disappear there is, as a matter of fact, minute fragmentation. (3) Fragmentation only occurs where there is no cell division. (4) Karyokinetic division of the nuclei is caused by the forces in the cell protoplasm, which bring about the division of the cyto- plasm. There is a series of phenomena in the division of the nuclei, with typical karvokinesis at one end, and direct fragmentation at the other. In Dr. Hickson’s opinion, the occurrence of any one kind or the other is determined by the forces which act simultaneously upon nucleus and cell-plasm ; and this view seems to be supported by the observations of Flemming and of Burger. Protozoa. Intranuclear Bodies.* — Dr. L. Rhumbler discusses the little bodies which occur in very variable number, size, and form within the nuclei of many Protozoa, and also within the germinal vesicles of Metazoa. * Zeitschr. f. wiss. Zool., lvi. (1893) pp. 328-64 (1 pi.). See this Journal, ante, p. 494. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 645 An observation made by Aime Schneider on the condensation of a cloud of fine granulations within the nucleus of Gregarines ( Actinocephalus , &c.) suggested to the author that the intranuclear bodies of Foraminifera and other Protozoa arise from the coalescence of substances at first fluid, then viscid, and finally firm. He works out this idea in detail, considering the various physical conditions in the process of coalescence. The bodies in question are not organized structures, certainly not cell-organs, but most likely aggregations of reserve material. Destruction of Bacteria by Infusoria.* — Mr. D. Harvey Attfield brings forward some evidence that the so-called self-purification of impure water may be due to Infusoria. Into two sterilized flasks there were introduced 500 ccm. of well-water which was estimated to contain 10,000 bacteria per ccm. To one flask there was added 10 ccm. of river Isar water, which swarmed with Infusoria (chiefly Paramsecium aurelia and P. caudatum). It was found, by plate cultivations, that in water swarming with Infusoria the bacteria had decreased to less than one-fifth their original number in six days, while in water con- taining few or no Infusoria the decrease of bacteria in six days was only one-half of the original number. Other experiments led to similar results. Coccidia of Birds. ] — M. A. Labbe finds that the Coccidia found in the intestine and caeca of Birds belong to two groups. Some belong to the genus Coccidium and are very near the C. perforans of the Babbit. In Passerines one frequently finds a spherical Coccidium with two equal sporoblasts, each enclosing four sporozoites ; for this form the author has made the genus Diplospora, which is intermediate between Cyclospora and Isospora. In addition to a chronic infection of Coccidia, Birds may suffer from an acute attack which may be fatal. The author’s observations suggest to him the question whether there may not be a dimorphism in development and an endogenous proliferation of sporozoites. Organization of Choanoflagellata.J — Herr B. H. Franze calls attention to some points in the organization of the Choanoflagellata. He finds that Biitschli’s account of the ingestion of food in Codosiga botrytis is hardly correct. The collar is connected with one of the contractile vacuoles by a fine curved line. This line corresponds to the boundary of a delieate plasmatic membrane, which, at times, leads to the vacuole, and it is by this membrane that the food-bodies pass to the digestive vacuole. It was the middle part of this membrane that Biitschli took for the mouth vacuole. The collar is not a circular ap- pendage closed on all sides, but a cornet-shaped membrane which takes part in the ingestion of food. The contractions of the vacuole are not pulsations but swallowing movements. The other, true, contractile vacuole pulsates at pretty regular inter- vals of about thirty seconds. It is remade by the appearance of one, then two, then three, very small vacuoles which suddenly unite ; at the same time there become apparent two fine longitudinal canals which * Brit. Med. Journal, 1893, i. pp. 1262 and 3. t Comptes Rendus, cxvi. (1893) pp. 1300-3. X Zool. Anzeig., xvi. (1893) pp. 44-G (2 figs ). 2 y 2 646 SUMMARY OF CURRENT RESEARCHES RELATING TO convey fluid to it. The vacuole enlarges and then becomes emptied through a small efferent canal. The body of Codosiga passes gradually backwards into the stalk, which must not be regarded as a secretion, but as a chemically altered, hardened part of the protoplasm. Fuller details are promised. iEtiology of Texas Fever.* — Texas fever is an infectious disorder of cattle, and according to Dr. Th. Smith, is endemic between the Gulf of Mexico, and 37°-8° N. ; it is marked by high temperature, profound and rapidly occurring anaemia and very frequently haemoglobinuria. The chief pathological appearances found post mortem are seen in the spleen, which is much enlarged and soft almost to diffluence ; in the liver, which not only is in a condition of parenchymatous degeneration but often of a necrosis starting from the central veins of the lobules ; and in the kidneys, where a haemorrhagic oedema is conspicuous. On examining the fresh blood during the febrile stage many of the red corpuscles will be found to contain a pale mass of mobile pro- toplasm. Various forms of the parasite Pyrosoma bigeminum sp. n. are depicted by the author. Most of them are in pairs, and in the youngest stage are oval, more or less, while later they are distinctly pyriform. The pyriform bodies may lie side by side or be attached by a narrow bridge of protoplasm connecting their thin ends. Some of the bodies show corpuscles in their interior. The parasite was stained by heating blood-films on cover-glasses for 1-1J hours at 110°-20° and staining for some minutes in alkaline methylen-blue. The preparations may be contrast-stained with eosin or decolorized with 1/3 per cent, acetic acid, but neither procedure is found to possess any particular advantage. In the circulation the number of corpuscles affected is rarely higher than 1 to 2 per cent., but in certain parts, as ascertained post mortem, much greater. Thus in the kidney 80 per cent, of the corpuscles are found to be infected ; in the liver, 30 per cent. ; in the spleen, 10 per cent. ; and in the heart muscle, 50 per cent. After death the intra- globular parasite is almost invariably round and rarely pyriform, and in its earliest stage, as well as in the mild or chronic form of the disease, the parasite is coccoid in shape. That it is intimately connected with the disease is obvious from the fact that healthy cattle are easily in- fected by subcutaneous or intravenous injection of blood from a diseased animal, and it is interesting to note that blood of healthy cattle from districts where the disease is endemic is capable of imparting the dis- order. The transference of the disease has been traced to ticks, Ixodes bovis vel Boophilus bovis by Kilborne who found that if the ticks were carefully removed from cattle so that the ground was not contaminated the disease did not break out, and further that meadows could be infected by scattering ripe ticks over them, even when diseased cattle were not present. The author concludes with some remarks on natural and acquired immunity and on cattle-diseases resembling Texas fever. iEtiology of Malaria.f — In describing the aetiology of malaria Prof. Laveran first alluded to the fact that he began to study the * Centralbl. f. JBakteriol. u, Parasitenk., xiii. (1893) pp. 511-27 (10 figs.), f Trans. Seventh Internat. Congress Hygiene, ii. (1892) pp. 10-8. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 647 question in 1878, while in Algeria, and then proceeded to describe the various forms of the parasite of malaria he had met with in human blood. (1) Spherical bodies with a diameter of 1-10 /z. These are endowed with amoeboid movements and in their later stages enclose pig- ment-granules. These are usually free in the plasma but may adhere to the red corpuscles. (2) Flagella : these are mobile filaments found adhering at first to the spherical bodies but afterwards becoming free. (3) Crescentiform bodies 8-9 /z long. These usually contain pigment- granules massed towards the centre and the horns of the crescent are frequently united by a fine filament. (4) Segmented bodies : these are represented as rings or circles of spherical bodies having in their centre a small collection of pigment-granules. (5) Leucocytes containing pig- ment-granules. These leucocytes are supposed to have seized on and devoured pigment-bearing parasites. The author considers that the malaria parasite is a polymorphic organism belonging to the class Sporozoa, and then goes on to point out that intravenous injection of mala- ria blood almost invariably succeeds in reproducing the disease and this parasite as well. The first symptoms are developed in 5-10 days after injection and this time suggests the incubation period. The author then passes on to review the relation between the blood- parasites found in animals and the haematozoa of malaria. In the red corpuscles of certain Vertebrates, especially of birds, are found forms strictly analogous to, and, indeed, resembling in almost every respect the parasites found in human malaria. But attempts to transfer this disease from one of these animals to another failed, although the parasite could be easily transferred from one individual to another of the same species. Thus Celli and Sanfelice have infected one lark from another, but failed in attempting to inoculate a pigeon with lark’s blood. Parasites of Red Blood-corpuscles.* — Prof. A. Celli thus compares the Italian doctrine of malaria with the views of Prof. Laveran. Both theories agree as to most of the facts, that is, there are forms free in the blood ; spherical bodies with or without flagella ; free flagella ; semi- lunar bodies ; forms adhering to or included in red corpuscles ; sporulat- ing bodies. The Italian observers, however, have described several other forms indicative of segmentation and dissemination : — (1) According to Laveran the free flagellum is the perfect parasite, the spherical bodies being merely cysts or sacs enclosing the parasite. According to the Italians the flagellated bodies are sterile, degenerative forms, and their movements, so to speak, expressive of their death struggle. (2) Accord- ing to Laveran the parasite is always free except, perhaps, in its early stage where it is found adhering to the surface of the red corpuscle, while the Italian writers consider it to be essentially endoglobular ; it is born and developed within the corpuscle, and if it leave before spore-formation it is sterile. (3) Both French and Italian schools accept the view that the crescentiform or semilunar bodies are degenerative conditions of the red corpuscles, directly due to the action of the parasites, though the latter observers maintain that this is only one of the degeneration forms of the parasite. (4) The segmentation bodies are the keystone or pivot of the Italian theory; this stage represents, according to them, the sporu- * Trans. Seventh Internat. Congress Hygiene, ii. (1892) pp. 20-28. 648 SUMMARY OF CURRENT RESEARCHES RELATING TO lation of the parasite within the red corpuscle, while, according to Laveran, these forms are almost accidental. (5) Reproduction is entirely endoglobular, according to the Italian theory, while Laveran describes a sort of budding as well as segmentation. (6) The author points out that the Italian theory has the following consistent cycle : — (1) Amceboid endoglobular corpuscles at first non-pigmented. (2) These afterwards become pigmented and increase in bulk. (3) There are now two different paths open to them, they may either sporulate, the spores becoming free in the plasma, or they may remain sterile. Under these circumstances they may get larger and larger, sometimes becoming free in the plasma (spherical flagellated form), sometimes remaining within the red corpuscles (crescent-shaped bodies). Parasitic Protozoa in Cancerous Tumours.* — Messrs. M. Armand Ruffer and H. G. Plimmer find that in carcinomatous tumours of the female mamma some of the Protozoa found therein inhabit the nucleus as well as the protoplasm of the' cancer-cell. The Protozoon often ap- pears as a small body in the nucleus, and then developes gradually until it exhibits the characteristics of the full-grown Protozoon. It then consists essentially of (1) a central round, oval or slightly irregular nucleus, sometimes connected by fine delicate rays with the periphery ; (2) a variable amount of surrounding protoplasm almost filling up the capsule ; and (3) a double contoured capsule which surrounds the whole. If the nucleus of a cancer-cell ever gets rid of the parasites, it appears to heal up in a wonderful manner, the details of which have yet to be studied. Intracellular Parasitism of Cancerous Neoplasms.t — According to Dr. J. Soudakewitseh, the cell-inclusions described by him are for the most part surrounded by a double contour. Within is found the parasite under the most diverse appearances, usually, however, enclosed by a homogeneous viscid material. The cell-inclusions appear at times in the form of granules irregularly disseminated, having a filamentous arrangement. Their staining reactions show the greatest differ- ences, for sometimes they are deeply stained with logwood, at other times not at all. Very good pictures are produced by safranin staining after fixation with Flemming’s fluid. The cell-inclusions are single or in accumulations, and scattered throughout the cancerous tissue, but especially on the superficial layers. The author thinks that these forms cannot be mistaken for cell-nuclei, as they differ therefrom not only in their staining relations, but also in their morphological attributes. Most of the cell-inclusions were found in cells, only a few were free, and usually these cells exhibited karyokinetic nuclei, or were hypertrophic, though occasionally their appearance was observed in necrotic cells. When the cancer cell is destroyed the enclosed parasite is set free, and then evacuates its contents, spores ; these find their way into neighbouring cells, or, if into the blood or lymphatic vessels, are carried away to colonize new territory, to which process the term metastasis should be applied. * Journ. of Pathol, and Bacteriol., i. (1893) pp. 395-403 (1 pi.). t Ann. Inst. Pasteur, vi. (1892) No. 8. See Centralbl. f. Bakteriol. u. Para- sitenk., xiii. (1893) pp. 399-400. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 649 New Cancer Parasite.* — Under the name JEtJiopalocepJialus carcino- matosus g. et sp. n. Kor., Prof. A. Korotneff describes a new parasite which he has found chiefly in Carcinoma labii, but also in cases of Carcinoma mammae, maxillae, &c. The adult form which receives its name from its somewhat club- shaped appearance, is an elongated ribbon-like body, with thickened head in which is a nucleus of variable contour. The outline of the animal’s body is well defined ; there are no pseudopodal extensions of the plasma, which is finely granular. In its more youthful state the parasite is found to inhabit the central portions of epithelial nests, and is less elongated and more rounded, and, according to the illustrations, exhibits from one to four nuclei. The developmental cycle is fully described. Starting with a cocci- dioid form, larvae or “ zooids ” are found within the interior. The zooids are elongated ovals in shape. Besides the zooids other off- spring, sporozooids, are developed ; these are crescentiform bodies, consisting of a hyaline investing membrane and protoplasmic contents. The subsequent career of the zooids is either to penetrate a cancer cell and there assume the Gregarine adult form, or become an encapsuled coccidium. The sporozooid phase, however, seems to remain free at first, and is observable between cells as a granular nucleated body chiefly distinguished by its pseudopodial extensions. After a time, not only may zooids but sporozooids be observed in its interior. The zooid always is metamorphosed into a coccidium, the sporozooid into an amoeba. The organism described forms a bond of connection between the Coccidia and Gregarinida, the free amoeboid and encapsuled forms point- ing to the Coccidia, the adult condition possessing characters more akin to the Gregarinida. According to the author the true reason why the amoeboid form has not hitherto been easily discovered is the method of preparation. If the specimens be treated with sublimate and cut by hand, the appearances described by him are easily observed. * Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 373-80 (15 figs.). 650 SUMMARY OF CURRENT RESEARCHES RELATING TO BOTANY. A. GENERAL, including the Anatomy and Physiology of the Phanerogamia. a. Anatomy. (1) Cell-structure and Protoplasm. Oligodynamic Phenomena of Living Cells.* — Under this name the late Prof. C. v. Nageli describes some very remarkable properties of living cells in their behaviour towards excessively small quantities of metallic substances in solution. The observations were made chiefly on Spirogyra nitida and dubia. If in water which is previously “ neutral ” i. e. not pathogenic to Spirogyra — a gold coin containing 10 per cent, of copper is placed, the water acquires the oligodynamic property of killing the Spirogyra in a very few minutes. The poison acts very much more energetically in the presence of only one or two filaments than if a larger quantity of the alga is present in the water. In this way 1 part of copper in 1000 million parts of water may be pathogenic. Glass vessels in which a piece of the poisonous metal had previously been placed acted in the same manner. In this way distilled water is often poisonous to Spirogyra. On the other hand, the presence in the water of certain insoluble solid substances, such as sulphur, carbon, wood, linen, cotton, gum, &c., and a large quantity of the alga itself, diminish its poisonous properties. Oligodynamic poisoning manifests itself in the living cell in a dif- ferent way from chemical poisoning. In the former case the protoplasm remains adherent to the wall of the cell, while the spiral band of chloro- phyll detaches itself, and becomes looped into a solid mass surrounding the cell-nucleus; the substance of the band swells up, and presents, on transverse section, a cylindrical or oval form. The oligodynamic poisoning may begin to manifest itself in a period as short as from three to six minutes. Prof. C. Cramer f has repeated the experiments of Prof. Nageli, and has confirmed the more important results obtained by him. Cell-nucleus of Spirogyra.J — Using Flemming’s chromo-aceto-osmic fluid as a fixing reagent, M. C. Decagny states that in Spirogyra seti- formis the nucleole produces a substance which it expels, sometimes through openings, sometimes by a complete rupture, the result being to bring into contact with the nuclear fluid a substance which immediately coagulates and takes a definite form. The nucleolar substances are, in Spirogyra , differentiated in the form of a large central body which, instead of disappearing, as in other nuclei, at the moment of division, persists after division has taken place. These substances bring about the reconstitution of the two halves of the nucleus by the assistance of a directing force located within the primitive nucleus. * Denkschr. Schweiz. Naturf. Gesell., xxxiii. (1893) 43 pp, f Tom. cit., 8 pp. X Comptes Kendus, cxvi. (1893) pp. 269-72, 535-7. Cf. this Journal, 1891, p. 360. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 651 Division of the Nucleus in the Asci of Peziza.* * * § — Herr S. Gjurasin finds, in the formation of the ascospores of Peziza vesiculosa , a mode of indirect division of the nucleus differing somewhat from that in the Exoasceae, the only group of fungi in which karyokinesis has at present been definitely detected. The method of staining employed was that of Flemming and Herrmann. The chief point in which the process differs from that in Endomyces is that the nucleole remains in existence until the division of the nucleus is complete. There is also less divergence of the elements of the spindle from one another, and the chromatic elements are less strongly differentiated. Wall of Vacuoles. t — By the use of a 1 p. m. solution of coffein, which causes slow contraction of the membrane, Dr. T. Bokorny has obtained further evidence of the invariable presence of a membrane or tonoplast surrounding the vacuoles in living cells. It is a portion of the protoplasmic contents of the cell, and is comparable in its properties to the parietal utricle. The best objects for observations are epidermal cells of the petals of Primula sinensis, Cyclamen europseum, and Tulipa, especially the red cells. (2) Other Cell-contents (including- Secretions}. Distribution of Mannite and Dulcite.J — According to Herr A. N. Monteverde, the presence of these substances is especially characteristic of the order Scrophulariaceae. Of 797 species belonging to 109 genera of this order, mannite was found in 272 species and 36 genera, dulcite in 26 species and 4 genera. They never occur together in the same species, and only in two instances in the same genus. Mannite was also found in a few Orobanchaceas, in Jasminiese, and in two species of Umbelli ferae ; dulcite in several Celastraceae. In RMnanthus, Euphrasia, and Melampyrum they are distinctly plastic substances, resulting from the transformation of sugar. Distribution of Calcium oxalate. — Prof. J. Borodin § distinguishes between two modes of deposition of calcium oxalate, differentiated and diffused ; the former where it takes place in special cells, the latter where it is distributed in all the cells of a tissue. In leaves diffused calcium oxalate occurs especially in the epiderm ; when present in the mesophyll, it is usually confined to palisade-parenchyme. It may occur in the form of separate crystals, clusters, or sphaGritic structures. Out of 913 (Russian) species of Angiosperms examined, 318 contained dif- ferentiated, and 40 diffused calcium oxalate, while in 548 this salt was entirely wanting in the leaves. The greater number in which the dif- fused form was present belonged to the Gamopetalse. Prof. R. Chodat and M. G. Hochrentiner |] record the occurrence of crystals of calcium oxalate in cells of the stem of Comesperma scandens, the internal coating of which is completely cutinized. * Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 113-7 (1 pi.). f Biol. Centralbl., xiii. (1893) pp. 271-5. X ‘ Ueb. d. Yerbreitung d. Mannits u. Dulcits,’ 37 pp. See Bot. Centralbl., 1893, Beih., p. 199. § Arb. St. Petersb. Naturf. Gesell., 1892, 56 pp. and 1 pi. See Bot. Centralbl., liv. (1893) p. 210. || Arch. Sci. Phys. et Nat., xxviii. (1892) pp. 495-6. 652 SUMMARY OF CURRENT RESEARCHES RELATING TO Perfume of the Orchidese.* — M. E. Mesnard finds that the substance which gives the perfume to the flowers of Orchideae is generally localized in the epidermal cells of the inner surface of the petals or of the sepals, sometimes also in the cells of the outer surface. (3) Structure of Tissues. Secondary Tissues of Monocotyledons.! — t)r. D. H. Scott and Mr. G. Brebner have carried on a series of investigations, chiefly on the following points : — The development of the secondary tracheids in Yucca and Dracaena ; the secondary growth in thickness of the roots of Dracaena ; and the secondary growth in thickness of Aristea corymbosa (Irideas). Under the first head the point which the authors set themselves to determine was the nature of the water-conducting elements in the secondary wood ; whether, according to the older view, they are tracheids, i.e. single cells grown to an enormous length, or whether, according to the statement of some recent writers, they are true vessels resulting from cell-fusion. The observations of the authors, made on both Yucca and Dracaena , and both by microtome-sections and by maceration, completely established the older view. The elements in question are tracheids, formed by sliding growth, each arising from a single cell, which may grow to from 30 to 40 times its original length, but remains uni- nucleate throughout its whole development. In the adventitious roots of Dracaena the secondary growth in thick- ness starts from a number of distinct points, the chief formation of secondary tissue beginning at the base of rootlets. At the base of the rootlet the thickening takes place entirely by means of a pericyclic cambium. The connection between the vascular tissues inside and out- side the endoderm is maintained by special bundles which traverse the endoderm at various points. Aristea corymbosa forms an indefinite amount of secondary tissue by means of cambium which continues active during the whole life of the plant. The xylem of the secondary bundles consists chiefly of tra- cheids arising from the enormous elongation of a single cell. The cambium arises in the pericycle, and is a new formation. Curvature of the Cell-wall of the Endoderm of Roots.! — Herr A. Rimpach discusses the cause of the frequent curvature of the radial walls of the endoderm of roots, which he thinks cannot in all cases be assigned to the causes to which it has hitherto been attributed, viz. tensions which take place only in the preparation of the object, and decrease of volume accompanying suberization. His own observations and measurements lead the author to the conclusion that the phenomenon is due to a shrinking of the cell- walls caused by contraction of the root. This contraction is most marked in the basal portion of the root, diminishing towards the apex, and is much feebler in the secondary roots. It is frequently also altogether wanting in the primary root, especially in certain orders of Monocotyledons. * Comptes Rendus, cxvi. (1893) pp. 526-9. Cf. this Journal, ante, p. 214. t Ann. Bot., vii. (1893) pp. 21-62 (3 pis.). % Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 94-113. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 653 Anatomy of the Begoniacese.* — M. C. Fellerer describes in detail tbe anatomical structure of the Begoniaceae, particularly in reference to the light it throws on their systematic position. Especial stress is laid on the structure of the cystolith-like structures, the nature of which differs in different species. The structure and distribution of these bodies favours the theory of the relationship of the Begoniaceae to the Cucurbitaceae. Anatomy of Phaseolese.j — From an examination of 44 out of the 47 genera of this tribe of Papilionaceae, and of nearly 300 species, Herr R. Debold states that they are distinguished by several anatomical characteristics from the rest of the order. The whole tribe is charac- terized by three-celled hairs and spherical or club-shaped glandular hairs. The stomates are always surrounded by two border-cells parallel to the fissure. The vascular bundles are always accompanied by crystals of calcium oxalate ; clusters of crystals are wanting, and raphides have not been observed in the Leguminosse. (4) Structure of Organs. Passage of Organs into one another.f — M. D. Clos insists that there is no sharp line of demarcation between organs in the vegetable kingdom ; even the distinction between stem and leaf is not an absolute one. The author classifies the various organs into elementary, filiform, and compound. Of intermediate organs he enumerates as many as twenty-three kinds. Seeds of Orchidese.§ — Mr. C. C. Curtiss describes the appearance and structure of the seeds of a number of American Orchideae. The more important differences noted are not correlated with those at present used in defining the genera, or even the tribes. The embryo possesses neither cotyledon nor radicle, resembling in this respect that of many saprophytes, such as Monotropa. On germination, the cells of the nucellus divide, and eventually form tuber-like buds, which ultimately give rise to the new plant. Two extreme types are described, one characterized by an elongated tapering testa and the elongated cells of the nucellus (e. g. Tipularia ), the other by an obovoid or inflated testa, and shorter, often equilateral cells (e. g. Corallorhiza , Hexalectris ). Testa of the Seed of Lythrarieae.|| — Herr W. Griitter describes the structure of the seed of a number of species of Lythrarieae belonging especially to the genera Cuphea , Lythrum , Heimia , Nessea , Peplis, and Ammannia. The seeds of the first two genera are especially character- ized by the presence of mucilaginous hairs in the epidermal cells, often coiled up and of great length, which swell up greatly and emerge from the cell on absorption of water. These hairs were shown by their chemical reactions to be composed of pure cellulose. In the forina- * * Beitr. z. Anat. u. Syst. d. Begoniaceen,’ Miinchen, 1892, xii. and 239 pp., 3 pis. See Bot. Centralbl., liv. (1893) p. 215. f ‘ Beitr. z. Anatom. Charakt. d. Pkaseoleen,’ Offenburg, 1892, 77 pp., 1 pi. See Bot. Centralbl., liv. (1893) p. 302. X Mem. Acad. Sci. Toulouse, iv. (1892) 23 pp. and 1 pi. See Bot. Centralbl., liv. (1893) p. 239. § Bull. Torrey Bot. Club, xx. (1893) pp. 183-92 (3 pis.). || Bot. Ztg., li. (1893) lt€ Abth., pp. 1-26 (1 pi.). 654 SUMMARY OF CURRENT RESEARCHES RELATING TO tion of the testa of the seed the nucleus of the anatropous ovule takes part, as well as the two integuments. The mucilaginous layer is the epiderm, the power of swelling residing chiefly in the elongated hairs or sacs which spring from the inner side of the cuticle. These hairs have often a very delicate flagel attached to their apex, and they escape from the cells in which they are formed by the raising up in the form of a lid of the portion of the cell-wTall to which they are attached. Their function is to fix the germinating seed firmly in the soil. Achenes and Seedlings of Composite.* — Mr. W. W. Rowlee de- scribes the peculiarities of the achene and seed, and of the mode of ger- mination, in the case of a large number of American Composite. The proportion of the apparently good seeds which germinate varies greatly in the different species ; it is often very small, largest in the most abundant species. Biology of the Pericarp.f — Referring to the fact of the necessity of a free access of air to seeds during the period which intervenes between their maturity and their germination in order to maintain them in an active condition, Prof. A. Borzi describes the mode in which this is effected in the structure of the pericarp of a number of fruits, especially those of Leguminosse. A very good example is furnished by the legumes of Phaseolus Caracalla , the seeds of which maintain their power of germination for as long a period as five years. The aeration of the seeds is here effected by two minute apertures in the ventral suture. Similar contrivances are presented by many other Papilionacese. In the ripe drupe of the cherry and plum, access of air to the kernel is pro- vided by the disappearance of the vascular bundle wdffch before maturity connects the ovule with its placenta ; its place is supplied by a sub- stance which absorbs water with great avidity. Structure of Runners and Stolons. :J — Herr A. 0. Noelle describes in detail the peculiarities of structure of runners and stolons, both underground and aerial. In underground stolons the formation of hairs and of stomates disaj>pears altogether, and the epiderm is more or less replaced by a layer of cork. The hypoderm becomes collenchymatous ; the cortical parenchyme is more strongly developed ; the vascular- bundle-system occupies a more central position than in aerial stems, tending towards the formation of a closed cylinder. The development of pith is, on the other hand, greatly reduced. Cotyledons of Tropseolum.§ — Herr A. Winkler points out that the pair of leaves which first emerge above the soil in the germination of Tropseolum majus are not, as has usually been described, the cotyledons. These remain buried in the earth. The first pair of leaves are opposite to one another and alternate with the cotyledons. In several other plants it is also the case that the first pair of leaves are opposite, while the subsequent ones are arranged spirally. The mode of germination is similar in T. minus , peregrinum , tricolor , and brachyceras , and probably in all other species of Tropseolum. * Journ. Torrey Bot. Club, xx. (1893) pp. 1-17 (5 pis.). f Malpighia, vii. (1893) pp. 3-14. X ‘ Beitr. z. vergleichend anat. I nters, d. Auslaufer,’ Freiburg-i.-B., 1892, 72 pp. See Bot. Centralbl., 1893, Beih., p. 94. § Abhandl. Bot. Ver. Prov. Brandenburg, 1892, pp. GO-2. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 655 Wool-climbers.* * * § — Herr E. Hutb enumerates a large number of plants, belonging to many natural orders, in which a facility for dissemination is afforded by the seeds or fruits being provided with stiff hairs or bristles, by which they become attached to the fur or wool of mammals, or to the plumage of birds. Prickles of Rosa sericea.f— M. P. Duchartre describes a remarkable form of prickle in this rare rose from India. In addition to the ordinary prickles, which resemble those of other species, and originate in quite the same way, there are found beneath each leaf a pair which broaden out into a remarkable laminated structure, not resembling anything known elsewhere in the vegetable kingdom. The author does not regard them as of a stipular character. Glandular Hairs of Brasenia.j — The thick coating of jelly which covers the surface, especially of the younger leaves, in Brasenia peltata (Nymphaeaceae), has been examined by Miss Ida A. Keller, and found to proceed from glandular hairs of the nature of colleters. They are either branched or unbranched, and proceed from the under surface only of the leaf. Root-tubercles of Elseagnus angustifolius.§— Herren F. Nobbe, E. Schmid, L. Hiltner, and E. Hotter have obtained root-tubercles on cultivated plants of Elseagnus by inoculation, and state that they are not produced by Bacterium radicicola , but by a totally different organism, of which pure cultivations were obtained, and of which a more complete description is promised later on. £. Physiology. Cl) Reproduction and Embryology. Process of Impregnation. || — An investigation of the processes in Taxus baccata leads Prof'. E. Strasburger to the same conclusions as BelajieffH with regard to the mode of impregnation in the Coniferae, but the number and period of the cell-divisions seem to vary even with nearly allied species. The large cells, which are first divided off from the pollen- cell, appear often to be subsequently resorbed. In the case of Welwitschia he confirms the statements of Juranyi ** on Ephedra. He asserts that in Gymnosperms the cell which is last of all divided off from the large cell of the pollen-grain is the true generative cell. In Biota and Juniper us, as well as in Taxus , the passage of this cell into the pollen-tube, and its final bipartition, were clearly followed out. In the Abietinese this division takes place within the pollen-grain. In Larix and Binus the number of chromosomes amounts to twelve. The author believes that the erythrophilous or cyanophilous character of the different nuclei depends on the conditions of nutrition. When * Abhandl. a. d. Gesammtgebiete d. Naturwissenschaften, iv. (1892) 24 pp. and 63 figs. See Bot. Centralbl., 1893, Beih. p. 100. Cf. this Journal, 1888, p. 253. f Rev. Gen. de Bot. (Bonnier), v. (1893) pp. 5-11 (3 figs.). I Proc. Acad. Nat. Sci. Philadelphia, 1893, pp. 188-93 (1 pi.). § Mittheil. Pflanzenphys. Versuchsst. Tharand. Die Landvv. Versuchsstation, xli, (1892) p. 138. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 195-6. || Histologische Beitrage, iv. (1892) pp 1-158. See Bot. Centralbl., liv. (1893) p. 78. ^ Cf. this Journal, 1892, p. 231. ** Tom. cit., 1885, p. 484. 656 SUMMARY OF CURRENT RESEARCHES RELATING TO well-nourished they are erythrophilous, while a stoppage of the absorption of nutriment from the cytoplasm renders them cyanophilous. The sexual cells of Gymnosperms are erythrophilous in proportion to the mass of cytoplasm by which they are surrounded. The nuclei enclosed in the small prothallium-cells are mainly cyanophilous, while the nucleus of the pollen-grain is erythrophilous, where the protoplasm, with the generative cell, makes up only a small portion of the pollen-grain ; in Ephedra, where it occupies three-quarters of the pollen-grain, it is cyanophilous. For the attractive spheres the author proposes the term astrosphere , and for the astrosphere, together with the surrounding centrosome, centrosphere. Astrospheres were detected in Sphacelaria , but they differed from those of higher plants in not doubling in number during karyo- kinesis. The term kinoplasm is applied to the hyaline constituents of protoplasm, which take part in active movements, but under the in- fluence of kinetic centres. In (Edogonium it is especially the kinoplasm which collects at the mouth of the archegone. The bladder, which encloses the swarmspore as it escapes, is the modified parietal utricle of the sporange. In other Algas also, and in some Fungi, the kinoplasm and astrospheres play an important part. In the formation of the antherozoids of Chara, the author agrees with the statement of Belajieff,* the cytoplasm taking part in their forma- tion, especially in the production of the cilia. In ferns also the two anterior coils of the antherozoids are of cytoplasmic origin, and the same is true of the cilia in the Muscinete. Neither in Characeae nor in Muscineae can he detect the spiral structure described by Schottlander.f As a general conclusion, the author states that three constituents of the protoplasm take part in the process of impregnation, viz. the nucleus, the centrospheres, and the kinoplasm. Embryogeny of the Birch.f — According to M. S. Nawaschin, the mode of impregnation of the birch differs in several points from that of typical Angiosperms, approaching the mode seen in the Chalazogams.§ The nucleus is differentiated into an outer tissue composed of short, and an inner one of elongated cells ; one cell of the latter becomes the embryo-sac. The pollen-tube never enters the cavity of the ovary, but grows into the tissue of the upper part of the suspensor, forces itself through the chalaza, and finally reaches the tissue of the nucleus at the apex of the embryo-sac. In the formation of short lateral branches, and in the constrictions, the pollen-tube of Betula also resembles that of Casuarina. Dr. 0. Fritsch || argues from this discovery the inadequacy of the mode of impregnation as a character for separating off the Casuarineee as a distinct class of Angiosperms. Distribution of Sexual Organs in Plants. — Herr F. Hildebrand % records examples of the replacement of male by female flowers in * Cf. this Journal, 1892, p. 237. t Cf. this Journal, ante, p. 203. % Bull. Acad. Imp. Sci. St. Petersbourg, xiii. pp. 345-8. See Bot. Centralbl., liv. (1893) p. 237. § Cf. this Journal, 1892, p. 230. II SB. K. K. Zool.-Bot. Gesell. Wien, xliii. (1893) pp. 15-6. i Bot. Zt,g., li. (1893) l,e Abtheil., pp. 27-35 (1 fig.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 657 monoecious plants in the following species : — Ecbalium elaterium, Bryonia alba , Quercus ilicifolia, Sagittaria sagittsefolia ; also of the occurrence of both male and female flowers in Urtica dioica , and in Juniperus , which are normally dioecious. From these abnormal instances he seeks to establish the following laws : — That the sex is determined before impreg- nation ; that external conditions at the time of impregnation have a powerful influence on the sex of the offspring ; that up to a certain period the descendants may be influenced by external conditions as to the sex of the flowers which they will produce ; and that these influences may be brought to bear on every single flower on the plant. M. L. Trabut * * * § gives an instance of a male date-palm producing a large number of dates which reached an advanced stage of maturity, but were entirely destitute of ovules. Fertilization of the Date-palm.f — M. C. Naudin calls attention to the fact that the female date-trees grown in Provence until recently produced, in warm summers, half-ripe fruits which contained no seed and which had not been impregnated ; while during the last few years dates have been produced obviously containing an impregnated ovule. This he believes to be due to intercrossing by the pollen, carried by bees and other insects, of a different species, Phoenix canariensis, which has been recently introduced into the district. Sexuality of Ceratonia Siliqua.J — According to M. E. Heckel the usual statement that the carob is polygamous-dioecious (i. e. has on one plant hermaphrodite, on another male and female flowers) is inaccurate. On a large number of specimens examined he was unable to find any true female flowers, those which have this appearance being really hermaphrodite and brachystemonous, i.e. they have sessile anthers concealed at the base of the calyx, and like it, of a dark red colour. The pollen-grains of these stamens are slightly smaller, but otherwise neither the anther nor the pollen-grains differ in structure from those of the male or of the dolichostemonous hermaphrodite flowers. These brachystemonous flowers are frequently abundantly fertile. They appear to be on the road to become female, but have not yet reached that stage, The author states that the apparent parthenogenesis of Coelebogyne paradoxa is explicable in the same way. Hermaphrodite Flowers in the Larch.§ — Dr. F. Noll describes hermaphrodite flowers found on Larix europsea. At the base of the female inflorescence the tuft of leaves was completely transformed into normal stamens containing pollen. Pollination by Insects. || — From observations, made on flowering plants in the Netherlands, Herr H. W. Heinsius comes to the following general conclusions with regard to the part played by different classes of insects in their pollination. Allotropous diptera have a strong preference for flowers with exposed or half-concealed honey ; hemi- * Bull. Soc. Bot. France, xxxix. (1892) Sess. Extraord., p. xxxviii. (1 pi.). f Rev. Gen. de Bot. (Bonnier), v. (1893) pp. 97-9. X Bull. Soc. Bot. France, xxxix. (1893) pp. 354-9 (4 figs.). § Yerhandl. Naturh. Ver. Preuss. Rheinlande, xlix. (1892) p. 57. || Bot. Jaarb. (Gent), iv. (1892) pp. 54-144 (11 pis.). See Bot. Centralbl., 1893, Beih. p. 203. 658 SUMMARY OF CURRENT RESEARCHES RELATING TO tropous diptera for flowers with half-concealed honey ; hemitropous hy- menoptera for flowers with half-concealed honey, and especially for clustered flowers ; eutropous hymenoptera for bee-flowers, and less decidedly for clustered flowers ; lepidoptera for flowers with concealed honey, and for clustered flowers, less decidedly for bee-flowers. Anemophilous and Entomophilous Plants.* — Herr O. Kirchner claims to have observed that several plants usually described as ane- mophilous are occasionally entomophilous. The vine, though generally self-pollinated, is sometimes abundantly visited by insects, and may accidentally be wind-pollinated. The flowers of the mistletoe are visited by insects. The male flowers of the sweet-chestnut are abundantly visited by honey-bees, diptera, and coleoptera. Chenopodium Vulvar ia and album sometimes secrete nectar, and are visited by insects, as also are Blitum virgatum and capitatum. Perforation of Flowers by Insects, j — Prof. L. H. Pammel gives an account of the species of plants, wild or cultivated in America, the flowers of which are perforated, either by insects or humming-birds, for the purpose of obtaining the honey. The most frequent perforators of flowers are species of Bombus , both females and workers ; but the honey- bee also occasionally obtains honey in this way. In southern latitudes, the carpenter-bees belonging to the genus Xylocopa also do considerable injury to flowers, as also do wasps ; but these latter more often visit flowers already perforated by species of Bombus. The humming-bird Trochilus colubris obtains honey in this way from several flowers. Occasionally the perforation assists rather than hinders pollination. The author also describes the contrivances for cross-pollination in Phlomis tuberosa and P. Busselliana. (2) Nutrition and Growth (including: Germination, and Movements of Fluids). Energetics of Plant-life. J — By the term “energetics” Prof. W. Pfeffer expresses the transformation of energy or force on which depends the power of an organism to perform its functions. He discusses in detail the mode in which energy can be rendered useful to the plant in carrying on its various vital processes. The manifestations of this energy are taken up in succession, as displayed in the processes of growth and movement, in the movements of water, and in the local transport of nutritive substances. When the movements concern imponderable molecules, the pheno- menon takes the form of chemical energy. Chemical energy becomes directly transformed into mechanical when a chemical reaction causes a change in volume or the elimination of some substance, as, for example, when crystals of calcium oxalate are formed in the cell-wall, and, by their growth, force apart the particles of which the wall is composed. Chemical energy is the source of electricity in plants, and also of the * Jahrhft. Yer. Yaterl. Naturk. Wiirttemberg, 1893, pp. 96-111. See Bot. Centralbl., liv. (1893) p. 367. t Trans. St. Louis Acad. Sci., v. (1892) pp. 241-77 (2 pis.). X Abhandl. Math.-Phys. KlasseK. Sachs. Gesell. Wiss., xviii. (1892) pp. 151-276. See Biol. Centralbl., xiii. (1893) p. 98. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 659 phenomenon of luminosity, dependent on respiration. When growth is simply the result of swelling, the resulting increase in size can be only limited ; active growth must be the result also of intussusception or the intercalation of particles of a solid substance. Neither imbibition nor capillarity nor air-pressure is sufficient to account for the raising of water to any considerable height in the vascular bundles ; it can only be explained by the action of forces which are constantly acting afresh at distinct points in the path of conduction of the water. Germination of the Cocoa-nut.* — M. L. Trabut describes the mode of germination of the seed of Cocos nucifera, which agrees in essential points with that of palms. When the embryo begins to germinate the cotyledon directs itself towards the cavity in the albumen, where it grows to an enormous size, and entirely fills it up, consuming the whole of the milky fluid which it previously contained. The whole of the endosperm is then also absorbed, commencing from within outwards. Relationship between Specific Size and Organization.! — Prof. J. Sachs discusses the questions of the limits of variation in size in any one species of plant, independently of variations in the supply of nutriment, and the correlation between the average size and the degree of complexity of the organizations. He lays it down as a general law that homologous organs of the same or of different species consist of cells of nearly uniform size, even when the organs themselves are of very different dimensions ; that there is no proportion between the size of an organ and that of the cells of which it is composed, the relative size of homologous organs being dependent on the number, and not on the size, of the cells. Nutrition of Insectivorous Plants.J — According to M. N. Tischutkin, in the secretion of insectivorous plants — Drosera rotundifolia and longi- folia , Dionsea muscipula, Pinguicula vulgaris , and N&penthes Mastersi — the process of digestion is entirely dependent on the presence of bacteria in the secretion, the part performed by the plant being only the fur- nishing of a substratum in which the micro-organisms can live. Increase in Girth of Stems.§ — From observations made on trees in the Botanic Garden at Edinburgh, Mr. D. Christison states that in favourable years the growth in girth extends over six months, from April to September, though usually the growing period is considerably shorter than this, both with Conifers and with Exogens. The months of greatest growth are almost invariably June and July, but with the tulip- tree August. The period of greatest development of the foliage does not always correspond with that of the greatest development of stem. Growth of the Leaf-stalk of Nymph8eaceae.|| — Prof. G. Arcangeli has determined that, in several species of Nymphaeaceee— Nuphar lutea , Euryale ferox — the leaf-stalks of the leaves which are still entirely sub- merged grow faster than those of the floating leaves. This he attributes * Bull. Soc. Bot. France, xxxix. (1892) Sess. Extraord., pp. xxxvi.-vii. (1 t Flora, lxxvii. (1893) pp. 49-81. j Acta Horti Petropolitani, xii. pp. 1-19. See Bot. Gazette, xviii. (1893) p. 105. § Trans. Bot. Sci. Edinburgh, xix. (1892) pp. 101-20, 261-333. See But. Centralbl., 1893, Beih., p. 196. II Bull. Soc. Bot. Ital., 1893, pp. 191-4. Cf. this Journal, 1890, p. 630. 1893. 2 Z 660 SOMHARY OF CURRENT RESEARCHES RELATING TO to the vertical pressure of the water on the upper surface of the sub- merged leaves due to the lower specific gravity of the leaf. Transport of Search in the Potato.* * * § — M. A. Girard confirms the statement of Prunet that the starch which is originally formed in the primitive cells of the tuber of the potato is dissolved as the shoots develope, and is transported towards the cells of these shoots, filling them up and becoming fixed in the normal form. Graft-hybrid.f — Mr. H. L. Jones records an instance of a graft- hybrid between two varieties of geranium, a pure white and a pure red one. Some of the flowers had two red and three white petals ; in others, some or all of the petals were red mottled with white. (3) Irritability. Irritability of the Tendrils of Passiflora.i — Mr. D. T. McDougal thus sums up his observations on the movements of the tendrils of Passiflora ccerulea and Pfordti. The tendrils and terminal internodes show circumnutation. The tendrils are extremely sensitive to contact with solids and with liquids at a temperature of 40° C., but are not sensitive to liquids at ordinary and low temperatures, unless they are so applied as to induce direct osmotic action, nor to slight electrical stimuli. Coiling round an object takes place on contact, while the formation of spirals takes place on maturity. The formation of the spirals exerts a tension of 3-20 grm., shortening the tendril one-third of its length; a mature tendril can withstand a strain of 350-750 grm. Contrary to the experience of Darwin with Bryonia and Echinocystis , the tendrils of Passijiora are sensitive to contact with one another. (4) Chemical Changes (including Respiration and Fermentation). Physiology of Leaves.§ — Mr. H. T. Brown and Dr. G. H. Morris give a historical resume of researches on the occurrence and formation of starch in plants, and then the result of experiments of their own, chiefly on Tropseolum and Eelianthus. They believe that starch is not a necessary link between the sugars of assimilation and the sugars of translocation, a large portion of the assimilated products not passing through this con- dition at all. The occurrence of diastase was found to be universal in quantity sufficient to transform the whole of the starch present in the leaf. It is to the presence of diastase, and not to the action of living protoplasm, that the disappearance of starch is due. The only sugars found in the leaves of Tropaeolum were cane-sugar, levulose, dextrose, and maltose, and of these maltose and dextrose appear to be the sugars which contribute most to the respiratory requirements of the leaf-cell. It is probably in the form of maltose that most of the starch passes from cell to cell. Function of Salts of Calcium and Magnesium. || — According to Herr C. Wehmer, the relative amount of salts of calcium and magnesium * Comptes Rendus, cxvi. (1893) pp. 1148-51. Cf. this Journal, ante, p. 355. f Bot. Gazette, xviii. (1893) p. 111. % Tom. cit., pp. 123-30. Cf. this Journal, 1892, p. 817. § Journ. Chem. Soc., 1893, pp. 604-77. Landwirthsch. Jahrb., 1892, pp. 573-70. See Biol. Centralbl., xiii. (1893) p. 257. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 6G1 in the ash varies greatly in different organs of the same plant, the pro- portion of magnesium being generally much the largest in the seed. Both elements are indispensable to the healthy growth of the plant ; but if no calcium is present, a very small proportion of magnesium is poisonous. Free oxalic acid in the tissues prevents the formation of diastase, and hence the conversion of starch into glucose and the trans- port of reserve materials ; the principal object of the calcium appears to be the removal of this injurious oxalic acid. To fungi, in which there is no formation of glucose from starch, oxalic acid is not poisonous. Calcium salts hence play an important part in the formation of chloro- phyll-bodies and of the nucleus. Production of Albumin in Plants.* — Herr A. Mayer maintains that the formation of albumin in plants is not due so much to the action of phosphorus as to the supply of highly nitrogenous food-material. The production of proteids is very rapid, and intermediate products, such as amides, do not exist for any length of time. B. CRYPTOGAMIA. Cryptogamia Vascularia. Axis of Vascular Cryptogams.! — According to M. J. Velenovsky. the branching of the axis of vascular cryptogams presents a greater resemblance to that of cellular cryptogams than to that of phanerogams. In the latter, with a few exceptional cases, there is no true dichotomy ; the branching is always monopodial. Among vascular cryptogams this is the case only in Equisetum ; in all others the axis can develope new branches at any spot, and there can be no regular acropetal succession. When the two branches into which the axis divides are alike, we have a dichotomy ; when they are dissimilar, the appearance of a monopode. The axis of vascular cryptogams is not segmented by the leaves like that of phanerogams, but is a unit which can divide at any spot without reference to the leaves. The Equisetace® may be compared to the Charace®, the Lycopodiaceae to the Hepatic®. Cellular cryptogams differ from vascular in never producing true leaves ; those of mosses are only emergences of the thallus ; the homologue of the true leaf in mosses is the sporange. There are no transitional forms known between the existing vascular cryptogams and the gymnosperms. Calcium oxalate in Vascular Cryptogams.!— M. G. Poirault disputes the statement made by several authorities that calcium oxalate is com- paratively rare in Vascular Cryptogams. Out of upwards of 500 species of Ferns examined, he finds this salt present in by far the larger number belonging to a great variety of different genera. It occurs also in the Hydropteride®, but has not yet been detected in Equisetum , Selaginella , or Psilotum. * Landwirthsch. Vers.-Stat., xli. pp. 433-41. See Journ. Chem. Soc., 1893, Abstr., p. 224. t Kozpravy ceske Acad., ii. (1892) 22 pp. and 2 pis. See Bot. Centralbl., Jiv. (1893) p. 299. 1 Journ. de Bot. (Morot), vii. (1893) pp. 72-5. 2z2 662 SUMMARY OF CURRENT RESEARCHES RELATING TO Sporocarp of Pilularia.* * * § — Prof. D. H. Campbell has followed out the development of the sporocarp of Pilularia americana, the structure of which presents a very close resemblance to that of P. globulifera , even in the number of loculi, which is four, and not three, as often stated. The resemblance to Marsilea is also very strong. The author regards the sporocarp as simply a modified portion of a leaf, and compares it to the fertile portion of the frond of Opiiioglossum, Osmunda, or Onoclea. The main difference between the sporocarp of Pilularia and the spore- bearing leaf-segments of Onoclea sensibilis is that in the former the sporanges are formed on the upper, in the latter on the under side of the leaf. Development of the Sporange in Polypodiacese.f — Herr C. Muller describes in detail the succession of cell-divisions in the formation of the sporange of several ferns ; his conclusions differ in some points from those of Reess and Kiindig. Cambial Development in Equisetaceae.J — Mr. B. G. Cormack has investigated the development of the cambium in recent Equisetacese ( Equisetum maximum ), especially in connection with the systematic position of the extinct Calamity. He finds a cambial activity in the nodes of the recent Equisetacese, and a corresponding secondary thicken- ing in all the Calamitae. The types of Calamitae whose structure is known form a closely connected series constituting a united group. In the Calamitae the cambial activity begins in the nodes and extends to the internodes ; while in living species of Equisetum it does not reach the internodes. The author considers that the evidence is strongly in favour of regarding the Calamitae as nearly allied to the Equisetaceae ; rather than of placing them among the Gymnosperms. Fossil Vascular Cryptogams.§ — The late carboniferous fossils of the basin of the Gard have been carefully studied by M. C. Grand’Eury. He divides the Calamariae into three sections, of which one comprises Annularia, while the two others include the Calamites and the Astero- phyllites. Stigmariopsis is distinct from the true Stigmarise , and consists, not of the rhizomes or stolons, but of the true roots of the Sigillarieae. The ferns of the Gard belong almost entirely to the Marattiacese, and to the genera Aster otheca, Scolecopteris, Pity cocarpus, Danseites , &c. Mega- phyton and Caulopteris are the arborescent stems of these ferns, of which the internal and subcortical portions have been termed Psaronius and Ptychopteris. Characeae. Anther ozoids of Characeae. || — Herr W. Belajieff has examined the structure and development of the antherozoids of several species of Chara and of Nitella flexilis, with the view of settling some points on which * Bull. Torrey Bot. Club, xx. (1893) pp. 141-8 (1 pi.). Cf. this Journal, 1892, p. 825. | Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 54-71 (1 pi. and 3 figs.). t Ann. Bot., vii. (1893) pp. 63-82 (1 pi.). § ‘ Sur la nature, la ve'getation et le port des Asterophyllites, Calamites et Arthropitus.’ See Bonnier’s Rev. Gen. de Bot., v. (1893) p. 230. |j ‘ Ueb. Bau u. Entwickelung d. Antherozoiden. I. Characeen Warschau, 1892, 49 pp., 1 pi. Seo Bot. Centralbl., liv. (1893) p. 200. Cf. this Journal, 1885, p. 484. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 663 previous observers differ. The material was fixed with osmic acid and alcohol, or with Flemming’s mixture, and double-stained with fuchsin and iodine-green. The author distinguishes three portions of the antlierozoid — a slender anterior, a central, and a thicker posterior portion, the first and last each including about half a coil, or rather more. The anterior part is stained red by the mixture ; the cilia which it bears are also stained red ; these are not placed, as is usually stated, at the apex of the antherozoid, but near the base of the anterior portion. The central portion is stained blue-green, but has an extremely delicate rose-coloured envelope. The posterior portion is stained red, but less intensely than the anterior part. From these reactions the author concludes that only the central portion of the antherozoid is formed from the nucleus of the mother-cell. The mode of development and the structure of the mother-cells of the antherozoids are described in detail, and direct observation supports the conclusion derived from the staining reactions, that the protoplasm, independently of the nucleus, plays an important part in the formation of the antherozoid. The cilia are from the first entirely free from the body of the antherozoid. Algae. Reinke’s Atlas of German Seaweeds. — Three more parts (iii.-v.) of the second volume of this valuable work are now published, and include 15 plates. The genera treated of are — Stilophora , HalorJiiza , Chordaria , Bhodocorton, Ectocarpus, Pogotrichum , Sphacelciria , and Stypocaulon. Plurilocular Sporanges of Chorda filum.*— Mr. T. H. Buffham describes the plurilocular sporanges in this genus of seaweeds. The axis of the plants on which they occur was always found to be twisted spirally. Variability of Desmidiese.f — From the examination of a large number of individuals of a species of Cosmarium Herr W. Schmidle comes to the following conclusions with regard to the limits of specific variability, which are probably true of all desmids, viz. : — The structure of the chlorophyll is constant in the same species ; the form of the cell varies within narrow limits ; the apical appearance is constant; the granulation is very variable. Apiocystis.J — Under special conditions of growth, Herr C. Correns finds, in Apiocystis Brauniana , besides megazoospores, microzoospores formed by repeated division of the vegetative cells ; no conjugation between them was observed. He describes also the occurrence, on the fixed colonies, of “ pseudo-cilia,” motionless cilium-like bodies, proceed- ing in pairs from each cell. These have no connection with the true cilia of the zoospores, and take no part in their formation; they are more akin to the hair-like structures of other algse. They are formed after the zoospore has come to rest, and each consists of a gelatinous sheath and a central thread of protoplasmic nature. When a cell divides, * Grevillea, xxi. (1893) pp. 86-8 (4 figs.). t Hedwigia, xxxii. (1893) pp. 109-15 (11 figs.). % Beitr. z. Morph, u. Phys. d. Pflanzenzelle (Zimmermann), Heft iii. pp. 241-59 (2 figs.). See Bot. Centralbl., liv. (1893) p. 146. 664 SUMMARY OF CURRENT RESEARCHES RELATING TO one pseudocilium goes to each daughter-cell, and a second is subse- quently formed. Similar pseudocilia were observed also in Tetraspora. According to the author, the enormous growth of the vesicle of Apiocystis (increasing 1715 times in volume) takes place neither by apposition nor by simple swelling, but by the intercalation of fresh substance from the side of the envelope. Fossil Algae. — Dr. A. Schenk * * * § gives an account of the fossil organ- isms at present known which undoubtedly belong to the Algae, from which he excludes Oldhamia , Eophyton , the Chondritese, and a portion of the Sphaerococciteae, the Fucoideae, the Spongiophyceae, the Dictyo- phyceae, and many others. Diatoms make their appearance for the first time in the upper Cretaceous strata ; the Bactryllia of the Trias may possibly be their ancestors. The cretaceous genera are identical with ours ; but the number of species appears to have increased enormously. The verti- cillate Siphonece do not appear to have existed before the Tertiary epoch, while the Corallineae may date from the Jurassic period. M. 0. Borge f has found in the glacial clays of the Isle of Gothland a number of fossil Desmids apparently belonging to existing Arctic types. Receptaculites and Bornetella.J — Dr. Rauff describes in detail the known species of the genus of fossil calcareous algae Bornetella, and compares with them the structure of Beceptaculites. He concludes in favour of the inclusion of this latter genus in the Siphoneae. Fungi. Effect of Parasitic Fungi on the Flower.§ — Herr P. Magnus de- scribes the effect of a number of parasitic fungi on the parts of the flower of the host-plant. Cystopus candidus on Sinapis and Brassica causes swelling of all the parts of the flower attacked ; while Peronospora violacea on Knautia arvensis , and P. Lin arise on Linaria minor produce no such result. Taphrina Pruni not only induces the familiar bladder- like swelling of the ovary, but also sometimes causes the filaments to swell up into a pear-like form. TJstilago antherarum incites the rudi- mentary stamens in the male flowers of Lychnis dioica to perfect development. AEcidium leucospermum produces no alteration in the flowers of Anemone nemorosa ; while AE. punctatum on A. ranunculoides causes more or less abortion in the different parts of the flower. AE. Magelhsenicum appears to exercise but little injurious influence on the development of the flowers of Berheris vulgaris. Effect of Poisons on the Spores of Fungi.|] — According to experi- ments made by Herr Wiitherlich, the spores of different fungi exhibit a very different power of resistance to the poisonous effects of the solutions of mineral salts or of acids. 124 parts by weight of cupric sulphide * ‘ Handb. d. Palaeontologie,’ 2te Abth., Munich, 1890, 69 pp. See Bonnier’g Rev. Gen. de Bot., v. (1893) p. 186. f Bot. Notiser, 1892, pp. 55-8. See tom. cit., p. 188. t Verb and 1. Naturh. Yer. Preuss. Rheinlande, xlix. (1892) pp. 74-90 (7 figs.). § Verbandl. Bot. Yer. Prov. Brandenburg, 1892, pp. vi.-viii. || ‘ Ueb. d. Einwirkung v. Metallsalzen u. Sauren a. d. Keimfabigkeit d. Sporen einiger parasitischer Pilze.’ See Biol. Centralbl., xiii. (1893) p. 265. ZOOLOG Y AND BOTANY, MICROSCOPY, ETC. 665 in 10,000,000 of water will prevent the germination or the formation of the spores of Peronospora viticola. In most cases the toxic property of the salt is its power of withdrawing water from the organism. Pythium and Saprolegnia.* * * §— Mr. T. W. Galloway finds that the fungus which causes the disease known as “damping off” in cultivated plants is Pythium Be Baryanum. It invariably attacks the roots first of all. It produces “ monosporous ” oogones, antherids, and zoosporanges within the tissue of the root and stem, and the hyphse sometimes extend to the leaves. In Saprolegnia monoica the author was unable to confirm the state- ment of Hartogf that the nuclei unite in pairs to form the so-called vacuoles. The mode of formation of the resting zoosporanges is de- scribed. Kryptosporium leptostromiforme.J — This name was given by Ktihn to an ascomycetous fungus found on lupins which had formed the food of sheep attacked by lupinose. Dr. M. Fischer has now traced out the life-history of this fungus on Lupinus luteus and angustifolius var. leuco- spermus. The only reproductive organs found were pycnids and pycno- spores, the fructification differing somewhat in size and other particulars, according as the fungus carried on a parasitic or saprophytic existence on the lupin stem. No formation of asci was observed ; this appears to take place very rarely, and possibly on a different host-plant. Structure and Biology of Lichens.§ — Dr. A. Minx propounds a modification of Schwendener’s view of the dual nature of lichens. The relation of the endophytic structures (gonids) to the lichen-tissue in which they are imbedded is not one of parasitism, but of what he terms syntrophism. The relationship of the former to the latter is rather that of a lodger ( Miether ) ; they do not live at the expense of the host, but rather dwell there for their own convenience, paying a tax to the host. The matrix is the true lichen, and many lichens have no such lodgers. A list of 133 lichens is given which are true “ syntrophs,” .arranged under the five tribes: — Parmeliacei, Calyciacei, Gyalectacei, Graphi- dacei, and Yerrucariacei, by far the greater number belonging to the Calyciacei. That the lichen does not consist necessarily of two distinct organisms is confirmed by the fact that the gonids are frequently found not only in the thallus but also in the apotheces. Another fact which supports the same view is that the same host will frequently entertain two lodgers belonging to different species. According as lichens carry on their existence with or without these lodgers, the author places them respec- tively under the head of “ autotrophic ” or “ heterotrophic ” lichens. The degree of influence of the lodger on the life of the host varies greatly, and often increases as time goes on ; that the cortical layer can be completely thrown off is strong evidence against the theory of parasitism. There are cases, on the other hand, in which the syntrophy appears to be entirely without effect on the host. * Trans. Massachusetts Hort. Soc., 1891, 10 pp. and 2 pis. t Cf. this Journal, 1887, p. 444. j Bot. Centralbl., liv. (1893) pp. 289-92. § Abhandl. Zool.-bot. Gesell. Wien, xlii. (1893) pp. 377-505. 666 SUMMARY OF CURRENT RESEARCHES RELATING TO Saccharomyces membransefaciens.* — Dr. J. Koehler isolated from dirty well water a yeast which he identified as Saccharomyces membranse- faciens Hansen. The fact is interesting, inasmuch as hitherto this organism had been lighted on only once before, and that by its dis- coverer. Flasks of sterile beer-wort inoculated by Hansen’s method with a drop of the water were incubated at 25°, and after two days a delicate whitish-grey scum formed on the surface. This scum was composed of much-branched hyphae, amongst which were imbedded yeast-like cells, mostly elliptical, often elongated, and but rarely round ; these were aggregated partly into irregular heaps, partly arranged in long chains. The majority of the yeast-cells contained small strongly refracting aseospores. The observation previously made by Hansen that there was consider- able difference between the superficial and the deep-lying colonies when cultivated on wort-gelatin or pepton-gelatin plates was confirmed. In the former the gelatin becomes slightly liquefied, the colony sinking down and assuming a reddish-yellow hue. On pepton-gelatin this Saccharomycete grows badly, and its development in liquid media is only pronounced when they contain carbohydrates. This is interesting, in- asmuch as the organism is unable to ferment dextrose, lactose, maltose, or saccharose, or to invert saccharose. This was confirmed by fermen- tation experiments, for which purpose sterile solutions containing known quantities of dextrose or saccharose were infected with the fungus and incubated at 25°. After seven days the solutions, which were covered with a thick scum of S. membransefaciens , were found to contain the same quantity of sugar as had been added (polarization). No alcohol was detected by the iodoform test. The scum developes best on beer wort, next on sugar or starch solution, but not at all on media devoid of carbohydrates. In the rapidity with which the scum forms on wort, S. membransefaciens is only exceeded by Mycoderma cerevisise. The author determined by Hansen’s method that at 25° spores were formed in forty- one hours, at 9° in ten days. Red Barley, f — Herr K. Klein has investigated the fungus which causes red spots or streaks in barley, — a species of Fusarium . The red pigment is contained in the cells themselves. The conids are sickle- shaped and may be either uni- or multicellular. Free oxygen is indis- pensable for the formation of the conids, but not for their germination. Gemmae are formed, especially when the conids do not develope fully ; and the middle cell of a multicellular conid may develope into a resting- spore. The author did not find these reproductive forms to be capable of causing fermentation. Histology of the Uredineae.J — MM. P. A. Dangeard and Sapin- Trouffy contest the statement that the mycele of the Uredineae is com- posed of typical uninucleated cells. The number of nuclei in each cell is seldom less than two, and it very commonly exceeds that number. A * Mittlieil. Oesterr. Versuchs-Station f. Brauerei u. Malzerei in Wien, v. (1892). See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 131-2. t Mittheil. Oesterr. Vers.-Stat. f. Brauerei u. Malzerei in Wien, v. (1892). See Bot. Centralbl., liii. (1893) p. 42. t Comptes Rendus, cxvi. (1893) pp. 211-3, 267-9, 1304-6, and Le Botaniste (Dangeard), iii. (1893), pp. 119-25. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 667 nucleolo is never present. The nucleus is composed of a hyaloplasm enclosing minute granulations of chromatin. Haustoria are present, and are as well developed as in the Peronosporese ; they have from two to six nuclei. In the pseudoperidium each cell has two nuclei, and the same is the case with the basids, the secidiospores, the uredospores, and the teleutospores ; four were observed in the uredospores of Uromyces Betse. In a number of species belonging to various genera, the same authors observed a coalescence of the two nuclei of the cells of the teleutospores, which they regard as a kind of pseudo-impregnation, a conjugation of rudimentary male and female elements similar to what takes place in Spirogyra. A similar fusion of nuclei takes place in the aecidiospores. This process of pseudo-impregnation is described more in detail in the case of Gymnosporangium Sabinse. It consists essentially in the fusion of the two nucleoles, which are, in these nuclei, large and sharply defined. Triphragmium.* * * § — Mr. G. Massee gives a monograph of the known species of this genus of Uredinese, and remarks that three forms of spore belonging to the teleutospore stage are to be met with in every species, viz. a radiately three-celled spore, which is by far the most abundant in nearly every species ; a spore composed of two superposed cells, each cell having a lateral germ-pore ; and a one-celled spore with lateral germ-pore. Parasitic Fungi. — In his report for 1892, Prof. J. E. Humphrey j describes the fungi which cause the following diseases in cultivated plants : — The sclerote disease of cucumbers, by Sclerotinia Libertiana> which probably possesses a conidial form of the Botrytis type ; powdery mildew by Erysiplne Cichoracearum ; downy mildew by Plasmopora cubensis ; damping off by Pythium Be Baryanum ; leaf-blight by Clado- sporium cucumerinum ; leaf-glaze by Acremonium sp. ; a violet disease by Phyllosticta Violae; black-knot of the plum, by PlowrigJitia morbosa ; powdery mildew of the strawberry by Sphserotheca Castagnei ; powdery mildew of the gooseberry by S. moro-uvse ; cluster-cup of the gooseberry by AEcidium Grossularise ; a disease of the hazel, by Cryptosporella anomala. Herr D. IwanowskyJ finds the tobacco-plant in cultivation to be subject to two diseases, one due to the attacks of Oidiurn Tabaci , the other to bacteria. M. E. Prillieux § describes a disease which attacks the endive, caused by the sclerotes of a fungus nearly allied to Sclerotinia Libertiana. According to Prof. J. C. Arthur and Miss K. E. Golden, || the sugar- beet-root is liable to two parasitic diseases, one due to a bacterium, the other to a fungus, Oospora scabies , identical with that which produces scab in the potato. * Grevillea, xxi. (1893) pp. 100-19 (7 figs.). f Rep. Massachusetts State Agric. Exp.-Stat., 1892, 39 pp. and 5 pis. Cf. this Journal, 1892, p. 831. t Land. u. Forstwirthsch., 1892. See Bot. Centralbl., 1893, Beih., p. 266. § Comptes Kendus, cxvi. (1893) pp. 532-4. || Bull. Purdue Univ. Agric. Exp. Stat., id. (1892) pp. 54-62 (1 pi.). 668 SUMMARY OF CURRENT RESEARCHES RELATING TO Fungus-parasite of Spirogyra.* — Herr Y. Chmielewskij attributes the formation of the “ stellate bodies ” in cells of Spirogyra to a fungus which he names Micromyces Spirogyrse. They are a resting-stage, and were made to germinate in hanging drops. The contents escape, and form a spherical body, surrounded by a very delicate membrane ; this divides into a number of wedge-shaped cells, which are no doubt zoosporanges, though the formation of zoospores was not actually ob- served. The infected filaments soon die ; the zoospores attack other filaments ; the germinating fungus puts out pseudopodes, and the whole organism then becomes encysted, and passes into the resting stellate condition. Classification of the Basidiomycetes. — M. P. Van Tieghem-f pro- poses the following classification of the Basidiomycetes ; — I. Acrospores : — Acrospore^j. A. Undivided (holobasids). a. Direct (euthybasids). a. Internal (angiospores). p. External (gymnospores). b. With probasids. B. Septated (phragmobasids). II. Pleurospores : — Pleurospores. A. Undivided (holobasids) B. Septated (phragmobasids). a. Direct (euthybasids). a. Internal (angiospores). /?. External (gymnospores). b. With probasids. a. Spores determinate. p. Spores indeterminate. Ly coper dacese. Agaricacese. Tilletiese. Tremellese. Tylostomese. Ecchynese. Auriculariese. Puccinacese. Ustilagese. The Basidiomycetes include all those fungi which have a thallus septated into immotile cells provided with a membrane of cellulose, and which produce their spores, usually in a definite number, on mother-cells specially called basids. The spores may be termed acrospores if formed at the summit, pleurospores if formed at the side of the basid. Dividing the Basidiomycetes into the two primary divisions of Acrospores and Pleurospores, each of these may again be subdivided into Holobasidese and Phragmobasidese , depending on the absence or presence of septa. The next character is derived from the circumstance whether the basids spring directly from the filaments of the sporiferous apparatus, euthy- basids, or whether through the intervention of a probasid on a kind of cyst, as in the Uredinese. In the ordinary literature of mycology such spores are erroneously called sporids, and the probasids, sporidia ; the basids being also incorrectly denominated a promycele. The Lycoperdacese comprise the Gasteromycetes, with the exception of the Tylostomese and the Ecchynese (the Pilacrese of Brefeld), which are erected into distinct families. The Agaricacese include the Hymeno- mycetes and the Dacryomycetes. The Ustilaginese and the Tilletiese * ‘ Ueb. d. Sternkorper in Spirogyra-7ie\\eTx’ 6 pp., 1892. See Bot. CentraJbl., liv. (1893) p. 262. t Journ. de Bot. (Morot), vii. (1893) pp. 77-87. ZOOLOGY AND BOTANY, MIOROSCOPY, ETO. 669 make up the Ilemibasidii of Brefeld. The Pucciniaceae correspond to the Uredineae of authors, and are removed from the Ascomycetes. M. P. Vuillemin,* while accepting Yan Tieghem’s classification in some important points, criticizes it in others. He dissents from the inclusion of the Ustilagineae in the Basidiomycetes, because they possess neither true protobasids nor basids. He also defends the separation of the Uredinem, and the use of the term teleutospore, that of probasid resting on an illusory homology. Pilose Tubercles of Agaricinese. j — M. Boudier has investigated the nature of the pilose tubercles frequently found on the pileus of Pleurotus ostreatus and some other Agaricinese, inaccurately called glands by some writers. He states that they are always caused by humidity, but not simply by the humidity of the air. The inciting cause appears to be invariably the egg of some dipterous insect deposited upon the pileus. Several species which have been founded on this accidental character must be abolished. Trichophyton megalosporon pyogenes.^ — M. R. Sabouraud main- tains that the tinea tonsurans of children, known under the name of kerion celsi, the tinea affecting the beard or sycosis circine, and the disease termed “ perifolliculite agminee ” (Herpes circinatus), are the same disease, the localization alone being different. The disorder is of fungoid origin, due to a special trichophyton, and in man is usually derived from contact with animals, more particularly the horse. In the horse the parasite causes a lesion closely resembling that in the human subject — a circinate folliculitis. In about 80 per cent, of human ringworm the hairy scalp is affected, the remaining 20 per cent, are cases affecting the smooth surface. About 2-3 per cent, are cases of sycosis menti. Microscopical examination reveals two kinds of parasites, one having spores 8-9 p, in diameter, and obviously contained within a mycelium, the other having spores 2-3 p. only in diameter, and without any distinct mycelium. The latter parasite, Trichophyton microsporon, causes the tinea tonsurans of children, the former, T. megalosporon , affects the hair of the scalp and beard and the smooth skin of all ages. That T. megalosporon affects the horse is proved from the case of a stableman attending horses suffering with a malady of similar appearance, and found to contain the same fungus. In all cases the presence of suppuration is a marked phenomenon, so that this class of parasite is termed pyogenic ; in the pus, however, the quantity of parasitic elements is small. Microscopical examination of the hair is best made by immersing it in a 40 per cent, solution of caustic potash, and inspecting the prepara- tion under a magnification of 300 with powerful illumination. Not only are the hairs invaded by the parasite, but the hair-sheaths also, and another point of diagnostic importance will be found in the presence of giant spores — spores having a diameter of 15-18 p,. The fungus was cultivated on gelose-beer-wort, pure or diluted to 1/5 or 1/10, and on potato. The optimum temperature was 18°. The * Tom. cit., pp. 161-74. t Kev. Gen. de Bot. (Bonnier), v. (1893) pp. 29-35 X Ann. Inst. Pasteur., vii. (1893) pp. 497-528 (2 pis. and 3 figs.). 670 SUMMARY OF CURRENT RESEARCHES RELATING TO growth has a white, powdery look, and attains its majority in about two weeks. Inoculation experiments made on man and animals were attended with positive results. Observation of cultures from a single spore stowed that this first produced a mycelium, in which spores might be observed. The mycele network goes on increasing, and about the sixth day masses of spores arranged like bunches of grapes are observable. The peculiarities common to Trichophyta in general are the spirals, the result of a mycele filament turning on itself, like a spiral spring on a vine tendril. The spindle, the third characteristic, is about 1/20 mm. long, and about 15 /x broad, and is divided up into compartments by transverse septa. Two Red Mycodermata.* — Herr A. Lasche found on hop-leaves two interesting yeast fungi, which belong to the Mycodermata, because they very quickly form a mouldy scum, and they are not able to produce spores in their interior. He lays it down therefore that My coderma is a kind of yeast which can form a scum, but no membrane, a definition hitherto unknown. (1) Mycoderma humuli. Cells oval, sausage-shaped, often very irregular. The cells sprout in the following way. From the side of the cell the development of a my cel-filament begins. When this has attained a certain length sprouts begin to form. The sprouts may appear either at the side or the ends of the filament, and from one cell several mycel- filaments may develope. On wort-gelatin the colonies of M. humuli showed short processes from the margins. Gelatin is liquefied in proportions of 10, 15, 20, and 40 per cent., and the degree of concentration exerted no influence on tbe rapidity of development. Saccharose, maltose, and dextrose were not fermented. In fermented beer this species will not develope, but will in beer-wort. It therefore differs from M. cerevisise and M. vini to which beer and wort are equally acceptable. No examination was made to ascertain if JIT. humuli possessed pathogenic properties. (2) Mycoderma rubrum. This species occurred as an accidental im- purity on gelatin plates, and therefore came from the air. Formation of a promycelium was rare. Its behaviour on gelatin was similar to that of M. humuli : neither dextrose, saccharose, nor maltose was fermented. The principal differences are that M. humuli frequently forms a pro- mycelium. Its cells have a diameter of 1*0 — 2*5 /x. M. rubrum rarely forms a promycelium and its cells measure from 1 * 5-3 /x . Both forms are stained red. The nine known Species of Favus.j — Drs. Neehe and Nuna define the genus Achorion to be colourless hypliomycetes consisting of septate liyphae which produce colourless fruit without the aid of fruit-hyphaB. On their natural medium, cuticle, hair, nail, the fruit-hyphae are trans- formed into spore-chains from which develope roundish or angular unicellular spores. On artificial media unicellular spores are developed under similar circumstances, and also aerial spores, after the formation * Der Braumeister, 1892, p. 278. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 485-7. t Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 1-13. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 671 of a free aerial mycele. Here and there bladders also are formed, and from these yellow masses are produced. The species of Achorion are parasitic on the horny layers of man and animals, whereon they form after a period the characteristic cups or scutulae. The nine species enumerated are: A. eutbythrix (F. griseus) ; A. atacton (F. sulfureus celerior); A. radians (F. sardiniensis) ; A. dicliroon (F. sulfureus tardus) ; A. alcromegalicum (F. scoticus) ; A. demergens (F . Batavus) ; A. cysticum (F. Hamburgensis) ; A. moniliforme (F. Bohemicus) ; A. larsiferon (F. Polonicus). The general differences of these species are then given in tabular form, after which are discussed their growth relations, and the classifi- cation founded thereon. The authors conclude their remarks by relating their cultivation and preparation methods, the results of which are massed together in tabular form. In most of their cultivation experiments the medium used was composed of 2 to 4 per cent, agar, 1/2 per cent common salt, 1 per cent, pepton, and 5 per cent, levulose. Mycetozoa. Hymenobolus, a new Genus of Myxomycetes.* — Under the name Hymenobolus parasiticus , Herr H. Zukal describes the type of a new genus of Myxomycetes belonging to the Perichsenacese, with the follow- ing diagnosis : — Sporangium singulare, regulariter circumlineatum, non pediculatum, fuligineum, minutum ; peridium simplex, sine incrustatione calcis ; capillitium in toto exigue formatum v. desideratum, lmvigatum, hyalinum ; sporidia majuscula, globosa, cum amplificato exosporio ab uno latere ; plasmodia miniata v. incarnata, in thallo lichenorum aliquorum parasitice sedentia, saepius in sclerotia, rarius in macrocystas v. micro- cystas mutantur. The sclerotes were first observed as bright red spots on lichens growing on a willow-tree. The young plasmodes creep along the bark of the tree till they reach the lichen, to which they attach themselves by the action of trophotropism, and on which they carry on a true parasitic existence, boring holes in the thallus often as far as the lower cortical layer. The plasmodes then become converted either into sclerotes or into megacysts and microcysts ; the ripe plasmodes expel their ingesta, and either become transformed into sporanges or move their position and then fructify. The parasitic habit, although it is only a facultative parasitism, distinguishes Hymenobolus from all the higher Myxomycetes. The pigment appears to be a lipochrome. Protophyta. a. Schizophycese. Scenedesmus. — Herr B. Franze f describes the structure of the membrane, chromatophores, and nucleus of Scenedesmus, especially of S. obiusus and acutus. The membrane has a very delicate rhomboidal areolation. Beneath this is a delicate layer of protoplasm, the granu- lations of which appear to form a continuous spiral ; and beneath this two * Oesterr. Bot. Zeitschr., xliii. (1893) pp. 73-7, 133-7 (1 pi.), f Beitr. z. Morph, d .Scenedesmus, 1892, 1 pi. See Bot. Centralbl., 1893, Beih.,p. 1G1. 672 SUMMARY OF CURRENT RESEARCHES RELATING TO other layers, the arrangement of the granules in which recalls the claters of the Hepaticse. The cliromatophore is also spiral, having sometimes the form of a figure of 8, while it is sometimes twisted like the chloro- phyll-bands of Spirogyra. Each chromatophore contains a pyrenoid. The nucleus is fusiform, and is surrounded by an envelope composed of intercrossing threads, and contains a nucleole. The protoplasm is therefore composed of distinct spirosparts. Prof. R. Chodat and M. O. Malinesco * * * § regard Scenedesmus and Dadylococcus as belonging to one and the same polymorphic genus, which may also occur in Pleurococcus, Gloeocystis , and Baphidium forms. From the absence of ciliated zoospores, the authors prefer to place Scenedesmus among the Pleurococcaceae rather than among the Hydro- dictyacese. Genera of Diatoms, f — M. J. Tempere gives a complete list of all generic names of diatoms employed since 1786, distinguishing those which he regards as well established. The name of one new genus, Leudugeria , is included. Atlas der Diatomaceen-Kunde. — Heft 46 of this magnificent work by Dr. A. Schmidt contains four beautiful folio plates (181-4). The species depicted belong mostly to the genus Melosira ; but there are some also belonging to Podosira, Butilaria, Actinodiscus , Adinoptychus , Craspedodiscus , Coscinodiscus, and Lepidodiscus. 0. Schizomycetes. Bacteria in Vegetable Tissues.^ — Mr. H. L. Russell asserts that vegetable, like animal, tissues are normally free from micro-organisms, but that many species of bacteria may live in healthy tissues for a con- siderable time. A series of injection experiments showed that species which are pathogenic for the animal body — such as Bacillus anthracis , B. diphtherise , B. cholerse-g allinarum, Micrococcus tetragenus, M. cereus Jlavus, Staphylococcus epidermis albus, and S. pyogenes aureus — are killed in a few days by living vegetable tissues, with the exception of S. pyo- cyaneus, which may live for many days, and even increase. With regard to saprophytic species, — while some, like B. megaterium and B. lactis aerogenes, do not increase ; others were found after from 20 to 50 days in large numbers, and extending to some distance from the point of inocu- lation ; among these were B. prodigiosus, B. butyricus , B. luteus , B. coli communis , and B. Jluorescens. Diseases caused by Bacteria.§ — Herr W. Migula enumerates five diseases of plants caused by bacteria, viz. : — the pear-blight and apple- blight of the United States, caused by Micrococcus amylivorus ; the Sor- ghum-blight of America, due to Bacillus Sorghi ; the disease which attacks young maize-plants in America, due to an undetermined bacterium ; the disease of hyacinths ; and the damp rot of potatoes, caused by an aerobic bacterium, formerly confounded with Bacillus amylobacter. * Bull, de 1’Herbier Bossier, i. p. 184. See Morot’s Journ. de Bot., vii. (1893) Bull. Bibl., p. lvii. f Le Diatomiste, ii. (1893) pp. 17-20. t Bot. Gazette, xviii. (1893) pp. 93-6. § Med. Proefstat. Midden-Java, 1892, 18 pp. See Morot’s Journ. de Bot., vii. (1893) Bull. Bibl., p. vi. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 673 Behaviour of Bacteria in small Intestine of Man.* * * § — Dr. A. Mac- fad yen gives an account of an investigation carried out in conjunction with Prof. Nencki and Dr. Sieber, on the contents of the human small intestine. The contents were obtained from an artificial anus, after excision of the ileum where it opens into the csecum. The object of the investigation was partly chemical, but specially to isolate the bacteria present in the normal small intestine and to study their action on proteids and carbohydrates. Three series of experi- ments were made, (1) during a meat diet, (2) during a mainly vegetable diet, (3) again during a meat diet. Numerous bacteria were isolated, and besides Schizomycetes, the intestinal contents were always crowded with fungi and yeasts. Most of the bacteria appear to have been aerobic, and of the anaerobic all were facultative. No putrefactive bacteria were isolated, and the reason for this is probably to be found in the acid reaction of the contents of the small intestine. The chief decomposition was found to be that of the carbohydrates, and not of the proteids, and the principal products were C02, H, acetic, succinic, and lactic acids, and alcohol. By comparing the results of the action of pure cultivations of seven bacteria isolated from the intestinal juice with the products obtained from the juice itself it was concluded that the fermentation of the carbohydrates is the result of bacterial action. The constant presence of alcohol in the small intestine and in the pure cultivations of the bacteria seems very interesting from a physiological point of view. The characteristic of the bacteria of the colon is the decomposition of proteids. Herein the reaction is alkaline and hence favourable to their action. Resistance of the Spores of Bacillus megaterium to dryness.f — From experiments he has made Mr. A. P. Swan, has come to the conclusion that spores of Bacillus megaterium will not retain their vitality when dried up for more than 4 \ years, a period far below that of B. subtilis or anthracis. Action of Light on Bacillus anthracis. :J — By a series of experiments on anthrax spores, Prof. H. M. Ward has determined that the action of sunlight not only has an inhibitory influence on the multiplication of bacilli ; but that the direct rays of the sun actually kill the spores ; and that this action is quite independent of temperature ; the effect is chiefly, if not entirely, due to the rays of higher relrangibility in the blue-violet of the spectrum. The electric light has the same effect. Other bacteria and some fungi are affected in the same way. White Corpuscles as Protectors of the Blood.§— Dr. Werigo ob- served that in rabbits almost all the leucocytes disappeared from the blood a few minutes after they had been injected with a cultivation of B. prodigiosus in a vein of the ear. * Trans. 7th Internat. Congress Hygiene, ii. (1892) pp. 60-4. f Ann. Bot., vii. (1893) pp. 153-4. t Proc. Roy. Soc., lii. (1893) pp. 393-400 (2 figs.); liii. (1893) pp. 23-44. § Ann. Inst. Pasteur, 1892, p. 478. See Centralbl. f. Bakteriol. u. Parasitenk xiii. (1893) pp. 241-3. 674 SUMMARY OF CURRENT RESEARCHES RELATING TO Systematic experiments with B.prodigiosus, B.pyocyaneus , hog cholera, fowl tubercle, and anthrax, usually showed that immediately after injec- tion of living or dead bacteria into the circulation there was an imme- diate and often considerable diminution of the leucocytes. The decrease was most manifest in the large multinucleated cells, the lymphocytes being less affected. If the animals survived, at not earlier than 15 hours after injection, the number of leucocytes increased until there were 3-4 times as many as at first. If the cultivations of B. pyocyaneus were filtered before injection, then leucocytosis occurred without previous diminution. Injection of carmine into the circulation also had the effect of causing a considerable diminution in the number of leucocytes for some hours. In order to explain the sudden and extraordinary diminution of the blood leucocytes after intravenous injections, the author suggests that the leucocytes immediately consume those elements and transport them to (internal) viscera; for examination of the liver of rabbits, killed directly after carmine injection, showed that in this case leucocytes laden with carmine were met with mostly in the liver capillaries and in ex- tremely intimate relation with the endothelial cells. According to the author’s description, the leucocytes are at once eaten up by the hepatic endothelial cells, so that giant cell forms arise. Quite similar appear- ances are presented after injection with anthrax, and the author surmises that it is of general occurrence for bacteria when injected into the cir- culation to be eaten up by leucocytes and carried off into the viscera. Attention is called to the fact that these results are opposed to the theory of Metschnikoff, according to which leucocytes possess a kind of selective power, and, on account of the negative chemotactic action of the tissues, should be incapable of consuming virulent bacteria. The author strives to minimise the force of this objection to phagocytosis by remark- ing that Metschnikoff may have made his observations either on infec- tions having a fatal termination or at the height of the process, while here we have to deal with appearances at the very beginning, or when as yet the tissues have not had time to make their influence felt on the organism. Nevertheless, it is quite clear that the author’s statements are opposed to the theory of phagocytosis, for if all the bacteria which may get into the blood are at once eaten up, then phagocytosis can- not be said to possess any decisive action on the course of the infective process. New Bacillus pathogenic to Animals.* — Dr. H. Laser describes a new micro-organism isolated from calves which died at a certain farm two or three days after birth. On agar plates inoculated from liver and lung of the diseased animals, large white colonies grew up in 24 hours. The bacteria when examined in hanging drops were seen to be short mobile bacilli. In intensity their movements were very variable. The bacilli stained easily with the usual anilin dyes. Cultivated on gelatin the organism grew along the inoculation track either continuously or in separate colonies. There was no liquefaction of the medium. On agar the surface was covered with a greasy slimy overlay. In puncture cultivations on agar and grape-sugar gelatin the growth was luxuriant, * Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 217-23. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 675 but tho remarkable feature was the copious evolution of gas, which was so great that it would push the agar up 2 cm. In bouillon the bacteria sink and no scum forms. The bacillus was found to grow equally well in the presence or absence of oxygen. Injection experiments showed that the micro-organism was pathogenic to rabbits, guinea-pigs, mice, and pigeons. The most constant post- mortem phenomenon was enlargement of the spleen, from which pure cultivations were mado. In those animals which survived for a week, suppurative peritonitis occurred, and if they lasted still longer, large masses of fat were found in the abdominal organs. Presence of Micro-organisms in the organs of those dead of Cholera.* — Dr. L. de Rekowski has made a number of experiments on cholera corpses to ascertain if the cholera bacillus be present in the tissues or organs. The author’s results are conclusive. In a very large number of trials cholera bacilli were found in parts of the body other than the intestinal canal. The method adopted was to cut out with the necessary precautions a piece about the size of a nut, and cul- tivate it in a liquid medium for 20-30 hours. The cultivation medium was Buchner’s fluid and a 2 per cent, solution of peptone. The latter formed about one-tenth of the bulk in each test-tube. Buchner’s fluid is composed of one part of bouillon in which cholera bacilli have been cultivated for two or three weeks. This is sterilized and then mixed with 10 parts of a half percent, solution of sea-salt. After mixing, the solu- tion is sterilized anew for half an hour at 120°. After the lapse of 20-30 hours the test-tubes were examined to see if they contained bacteria. If they did, four plates were inoculated and the colonies which grew up were re-implanted in gelatin, potato, and bouillon. Examination of brain, spinal subarachnoid fluid, heart, clot in heart, liver, bile, spleen, kidney, and voluntary muscle showed the presence of cholera bacilli, together with other bacteria in a large percentage of cases. From this the author concludes that the prevalent opinion about the cholera bacilli being restricted to the gastro-intestinal tract is unfounded. Pathogenesis of Anthrax in Guinea-pigs and Rabbits, t— It has been held by many that in its pathogenesis anthrax in man and cattle is a local disorder with slight extension into the circulation and the rest of the body, while in other animals it has a more hsematogenous character. Drs. G. Frank and O. Lubarsch have made experiments with the view of finding out how soon post infectionem anthrax can be demonstrated by cultivation methods in the blood and internal organs. In guinea-pigs the micro-organisms were never found before seventeen hours, and were never absent after twenty-two hours. Within this period, therefore, the bacilli pass into the circulation first of all, and in greatest numbers into spleen, lungs, and liver. Rabbits evinced considerable individual differences in the resistance to infection, and the number of micro- organisms present in tho internal organs was subject to great variations, but they were hardly ever absent. * Arch. Sci. Biol. Inst. Imp. de Med. Exp. a St. Petersbourg. i. (1892) pp. 517-31. t Zeitsclir. f. Hygiene, xi. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 283-4. 1893. 3 A 676 SUMMARY OF CURRENT RESEARCHES RELATING TO The authors came to the conclusion that anthrax in small animals — mice, guinea-pigs, rabbits — is at first a local disorder, and if, owing to diffusion of their toxic products from the bacilli at the inoculation site, the bactericidal influence of the blood be overcome, then a free dis- semination in the blood may ensue. Pleomorphism of Tubercle Bacillus.* — In connection with a commu- nication of Fischel, who states that his investigations into the morpho- logy and biology of the tubercle bacillus lead him to the conclusion that what is now known as tubercle bacillus is the parasitic form of a micro-organism originally saprophytic, forming branched filaments, and also club-shaped elements having resemblance to Actinomyces , Dr. E. Klein claims that, in 1890, he pointed out that in some cultivations in glycerin-agar and bouillon, the tubercle bacilli were found with branched mycele-like filaments and bulbous end-expansions. Between these filaments and the typical tubercle bacilli all kinds of intermediate forms were found. All these forms assumed the typical tubercle stain, and about the purity of the cultivations there was no doubt. The author then stated, “ The tubercle bacillus as met with in the human and (other) animal bodies, in serum cultures, and in the first months in glycerin-agar and bouillon cultures, is but a phase in the life-cycle of a micro-organism morphologically allied to mycele-fungi.” Hog-Cholera and Phagocytosis.f — Prof. E. Metschnikoff pursues his studies on immunity, and from experiments made with the bacteria of hog-cholera, finds that protection against this disease is due to the active interference of phagocytes. His conclusions are that : — (1) The serum of rabbits vaccinated against hog-cholera does not possess bactericidal or antitoxic properties. (2) The same serum does not possess the power of attenuating the virulence of the microbe of hog- cholera. (3) Despite the absence of the foregoing properties, the serum of vaccinated rabbits preserved fresh unvaccinated rabbits against fatal infection from the bacteria of hog-cholera. (4) This property is not found in the liquid oedema set up by stoppage of the circulation. (5) The bactericidal property of the organism of vaccinated rabbits resides in the phagocytes. (6) The pus of vaccinated rabbits retains for a long time virulent microbes. (7) The organism of vaccinated rabbits is very sensitive to the toxines of hog-cholera, and is not pos- sessed of any antitoxic property. (8) Phagocytes play a very import- ant part in the resistance of vaccinated rabbits. (9) Phagocytes also play a very important part in the resistance of rabbits unvaccinated, but treated with the preservative serum. Under these circumstances it is probable that this liquid exerts a stimulating influence on the phago- cytes. Clasmatocytes and their Relation to Suppuration.^ — Prof. L. Eanvier detected the existence of clasmatocytes by treating the femoral aponeurosis of the frog successively with osmic acid and methyl-violet 5 B. Side by side with the fixed cells were other cells stained deep violet, and having all the morphological characters of the migratory * Centralbl. f. Bakteriol. u. Parasitenk., xii. (1892) pp. 905-6. f Ann. Inst. Pasteur, 1892, p. 269. X Comptes Rendus, cxvi. (1893) pp. 295-7. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 677 cells of the cornea prepared with gold chloride. Similar cells were found in other parts of the frog, when the tissues were examined after the same method. Analogous cells were observed in the mesentery of the crested Triton, and when examined in their own plasma were found to be devoid of movement and incapable of amoeboid prolongation. If a non-microbic peritonitis be induced, as by the injection of a dilute solution of silver nitrate into the sac, the clasmatocytes become changed, in situ, into lymphatic cells, they reassume their embryonic form, and multiply rapidly by direct division. Hence they are the principal source of suppuration. The clasmatocytes are neither fixed connective tissue- corpuscles, nor are they leucocytes. Toxic Principle of Bacillus lactis aerogenes.* — Prof. J. Denys and M. E. Brion record experiments made with B . lactis aerogenes ( B . pyogenes d’Albarran and Halle), an organism first found almost in a state of purity in the stools of suckling infants by Escherich. Recently, A. Morelle has shown that this organism plays an important part in urinary affections, and though much of importance as to its morphology and biology are known, its toxic principles have been little studied. Tho organism was grown on potato, whereon it forms a thickish layer, which is easily scraped off and can be weighed and mixed with fluids. As a cultivation medium potato has the further advantage of being free from pepton, sugar, and other substances entering into the composition of bouillon and gelatin. The pale yellow-brown growth was weighed and mixed up to 10 per cent, with distilled water or physiological solution, and then ether or chloroform added to kill the microbe. The effect of large doses on the rabbit was an energetic action on the central nervous system. After an extremely short stage of excite- ment, general paralysis set in, and this might be accompanied by tetanus. In smaller doses the most striking phenomenon was emaciation. The poison was obtained by passing the aqueous emulsion through a Chamberland or Nordtmeyer filter, and using the filtrate or simply the clear supernatant fluid; and in course of these observations it was determined that the poison was extremely diffusible in water, and that 2-3 cubic centimetres of the fluid obtained either by filtration or deposit are about equivalent to one cubic centimetre of the emulsion. The poison showed a remarkable resistance to high temperatures, there being no apparent diminution of its virulence after exposure to 100° for 15-20 minutes. After 45 minutes to 3 hours at the same temperature, there is manifest diminution, and after an exposure of 6 hours the dose requires to be four times as large. The nature of the poison was examined by Brieger’s method, but no ptomaines from potato cultivations were obtained. Gautier’s method and attempts to extract an alkaloid by solvents such as chloroform, ether, and alcohol, either simply or after acidification with acetic or hydro- chloric acid, were equally unsuccessful. The poison hitherto suspected of being a toxin was afterwards determined to be a toxalbumin. It is soluble in water ; it is precipitated from this solution by alcohol ; it is of a colloid nature and non-dialysable ; it becomes incorporated with precipitates such as calcic phosphate. The authors further find that neither the gastric nor the pancreatic * La Cellule, viii. (1892) pp. 305-32. 3 A 2 678 SUMMARY OF CURRENT RESEARCHES RELATING TO juice has any action on the toxalbumin, that it is not destroyed hy oxygen nor affected by the action of light. Though the alkaloidal nature of the toxin is negatived, the authors do not definitely class it among the toxalbumins, to which it is allied by its insolubility in alcohol, and its colloidal nature on account of its resistance to heat and the digestive juices. Bacillus pluviatilis.* — Dr. A. B. Griffiths describes under this name a microbe discovered in rain water which had been stored in an open barrel during a mild winter. When cultivated on gelatin plates it forms yellow colonies 2-10 mm. in diameter. It liquefies gelatin, and developes rapidly, when grown on a piece of potato, colouring it orange, and transforming the starch into glucose. It is a true bacillus, and is not formed from spores ; it is 2-4 fx long, 0 • 6-0 * 8 /x broad, and is stained by anil in colours. It can live only in water containing organic matter ; the cultures may be dried, but are killed by heating to 100° C. for 15 minutes. It does not appear to be pathogenic. Bacillus typhosus and Bacillus coli communis.— MM. A. Rodet and G. Roux j* were the first to point out that the bacillus of enteric fever may, under certain circumstances, produce suppuration, and that Bacterium, eoli plays a part in affections of the bile ducts. They further showed that, while Bacillus typhosus is found in the splenic blood of enteric fever cases, B. coli exists in the intestine of these patients, almost in pure cultivation. From examinations of water suspected of typhoid, micro-organisms which could be positively identified with B. entericus were never found, while B. coli was often present. The position of the authors is that the typhoid bacillus is merely a variety of Bact. coli , and they now give the result of their experiments on animals. In the anatomical lesions found in rabbits and guinea-pigs there was a striking resemblance, although those produced by Bact. coli were perhaps more intense. The temperature changes resulting from intra-peritoneal and intravenous injection of both organisms point to the conclusion that these organisms cannot be easily distinguished from the standpoint of experimental infection. MM. Chantemesse and Widal f find that the typhoid fever bacillus cannot set up an alcoholic or a lactic acid fermentation in nutritive media. Coagulation of milk does not occur even if a typhoid milk cultivation be kept longer than two months. The observations are a direct contradiction of the statements of Dubief, who found that the fermentative action of typhoid bacillus and of the common bacterium of the large intestine was equally great, that the quantitative difference between the formed products of fermentation was very slight, and that Bacillus typhosus was able to coagulate milk even after a long period. The objections raised by Rodet and Roux are also controverted. The authors left B. coli for two months in an incubator until it was almost dried up, yet the colon bacterium had lost none of its characteris- * Bull. Soc. Cliim., vii. pp. 332-4. See Journ. Chem. Soc., 1893, Abstr. p. 83. f Arch. Med. Exp. et d’Anat. Pathol., iv. No. 3. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 139-40. Cf. this Journal, ante , p. 86. X La Semaine Med., 1891, No. 45, p. 451. See Centralbl. f, Bakteriol. u. Parasitenk., xii. (1892) pp. 730-1. ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 679 tic properties or of its coagulative power. Bad. coli cultivated in media to which 1/800 phenylic acid or 1/400 tartaric acid had been added and kept for six weeks at 37°, showed many microbes, which corresponded morphologically and biologically with B. coli. The authors have further determined that B. coli is killed in a few seconds by the action of a temperature of 80°. liodet and lioux regard the typhoid bacillus as a variety of B. coli produced in the organism of the typhoid patient. Yet when B. coli is pathogenic to man, and has been the cause of a local or general infection, its peculiar characters are retained, and do not resemble those of typhoid bacillus. In typhoid fever secondary infections set up by B. coli are not uncommon, and these are manifested by certain symptoms. In such cases B. coli is demonstrable with all its characters. When passed through the body of sensitive animals, such as rabbits and guinea-pigs, the typical characters of B. coli remain unaltered. Dr. A. Pere * cultivated the Escherich bacillus in various albuminous media, and found that its growth in bouillon mixed with syntonin pepton- gluco ;e or dextrin was extraordinarily rapid, but slower if cane or milk sugar were added. The growth of Eberth’s bacillus was strikingly inhibited in the presence of the sugars. In albuminous media the reaction of the media for both bacteria was at first acid, afterwards becoming alkaline. In fresh meat-bouillon the growth of B. coli only excites an acid reaction, while in typhoid bacillus this reaction changes after five days to alkaline. The indol reaction was obtained in all those cases where B. coli was cultivated in presence of pepton or of albumen associated with peptonizing ferments. B. coli can decompose glucose and saccharose in peptonized media if access of air be unimpeded, while Eberth’s bacillus never gives the indol reaction under the above-mentioned conditions, nor is it able to decompose the sugars, except cane and milk sugar. Virulence of Streptococci. | — Dr. H. de Marbaix, after a historical critique of the unicist and dualist views of pathogenic streptococci, avows himself a unicist, on the ground that the separatists had not taken into account two facts which the author considers are established by his experiments. First, the virulence of a given streptococcus varies con- siderably, according to its origin. Secondly, the primitive virulence is subject to considerable oscillations, sometimes more, sometimes less. The monograph is too long to quote more than the general features and conclusions. The author is chiefly concerned in controverting the position of Von Lingelsheim and Kurth, who divided streptococci into three chief classes — pyogenic, erysipelatous, and scarlatinal. These observers attached considerable importance to the differences in the appearances of the cultures, and more especially of the deposits, but no part of their diagnosis was based on the results of injecting animals with the cultivations. On this deficiency the author lays much stress, and thinks his objec- tions are fatal to the dualist view. The conclusions arrived at are: — (1) The virulence of streptococci varies considerably, according to the disease from which it comes. * Ann. Inst. Pasteur, vi. 1892, No. 7. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) p. 285. f La Cellule, viii. (1892) pp. 257-301. 680 SUMMARY OF CURRENT RESEARCHES RELATING TO (2) In a general sense, the more severe the disease, the more virulent is the streptococcus. (3) The virulence is easily measured ( a ) by inocu- lation on a rabbit’s ear ; ( b ) by inoculation on a serous membrane. (4) The virulence of one and the same streptococcus is liable to variation. It is increased by being passed through the rabbit ; it is diminished or lost if not resown. (5) Any particular streptococcus will acquire a high degree of virulence so much the more quickly according as it is already possessed of a greater degree of virulence. (6) Non-virulent strepto- cocci acquire pathogenic properties if they bo associated with irritant liquids such as the bile. (7) Streptococci from the mouth are habi- tually less virulent, but their virulence may be increased by passage through animals. (8) Virulence is not associated with any special kind of development in bouillon. (9) The works of Von Lingelsheim and of Kurth on the classification of streptococci are fundamentally defective, inasmuch as they did not take into account the variation of virulence. Bacillus mucosus ozsenae.* — Dr. R. Abel describes a bacillus which he isolated from cases of Rhinitis atrophicans foetida or Ozsena vera, a catarrhal inflammation of the nasal mucosa leading to atrophy, in which the secretion soon dries and exhales a very unpleasant odour. The bacilli are short and plump, frequently arranged in pairs or in chains, and have much resemblance to Friedlander’s pneumobacillus. Not unfrequently they are surrounded by a capsule which may be twice as broad as the rodlet. The organism was cultivated with facility on all the usual media, and succeeded best at incubation tem- peratures and with free access of air, although its growth was not materially interfered with at room temperature and in the absence of oxy- gen. On all media a peculiar smell likened to the odour from ferment- ing malt was perceptible. The development of the bacilli was but little interfered with by differences in the reaction of the medium. The bacilli were easily stained with all the usual anilin dyes, and on heating cover-glass preparations with alkaline methylen-blue or phenol fuchsin, the capsules were so deeply stained that the bacilli were hidden. Gram’s method failed. The microbe is pathogenic to white mice, the greatest change being found in the spleen, which is much enlarged and congested. The blood reeks with ozaena bacilli. Rats and mice were refractory to subcutaneous injection, but suc- cumbed to injections into abdominal cavity and into lungs. The author then points out, at considerable length, the characters which distinguish B. mucosus ozsense from other bacteria of somewhat similar appearance. Micro-organisms of the Mouth. | — Dr. E. W. Roughton has brought together, in an interesting and useful form, an account of the micro- organisms of the mouth, and their effects on the mouth and other parts of the body. Many of the troubles to which the mouth is subject are undoubtedly due to them, and they are found in great numbers and considerable variety. * Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 161-73. f Trans. Odontol. Soc. Great Britain, xxv. (1893) pp. 71-88 (6 pis.). ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 681 Growth of the Comma Bacillus on Potato.* — Dr. H. Krannhals records the results of numerous cultivations on potato of the comma bacillus made during the last epidemic at Riga. The varieties used were the “ Oschlapping,” a “ red ” and a