bluuebunny/crossref_metadata_2025 huggingface dataset:
Maturation of the Ovum in Echinus esculentus
Authors: Bryce Thomas H.
Published: April 2021

The subject of the maturation of the sexual cells is a thorny terrain. It can be attacked only by the highest powers of the microscope, and the facts can only be reached by a process of patient mental reconstruction of the various phases. Historically the subject has been overlaid by some brilliant but premature hypotheses, which, however much they may have stimulated research, have also tended to foster prepossessions. The necessary stimulus for research has been supplied by the hypothesis that the chromatin of the nucleus is the hereditary substance, or, at least, the bearer from one generation to another of hereditary qualities. But apart from the interest connected with problems of heredity, and the meaning of fertilisation, the study of the intricate details of the process of maturation goes to the bottom of all our knowledge of cellular morphology. The study of the maturation phenomena in Echinus was, in the first place, taken up merely with the motive of seeing some of the actual phases in the most readily obtainable material. But it was soon discovered that although the outward phases had been frequently studied, most of the finer details of the process, as seen in Echinus, were undescribed, and therefore it was considered worth while to make a study of the whole process.
On the Morphology of the Cheilostomata
Authors: Harmer Sidney F.
Published: April 2021

The observations on which the present paper is based were commenced with the examination of a Flustra-like Cheilostome, found at Port Jackson by Mr. T. Whitelegge, who sent it to me for description, believing it to belong to a new genus. Although exhibiting several remarkable features, I think it may be placed in Euthyris, Hincks, and I propose for it the name E. clathrata, in allusion to the bars which support its “frontal wall?’ The species possesses a large “compensation-sac/’ a name which is due to Jullien (1888, 1), although the structure had to some extent been described by Busk and Waters. Jullien’s results have usually been discredited by later writers. The study of a number of Cheilostomatous genera has, however, not only led me to confirm the accuracy of Jullien’s statements, but has resulted in various conclusions which I believe to be of importance for the proper understanding of the Cheilostomata. A summary of my principal results has been communicated to the Cambridge Philosophical Society (1901).
The Genera and Species of the Order Symphyla
Authors: Hansen H. J.
Published: April 2021

In 1884 Dr. R. Latzel published the second half of his fine and highly valuable work ‘Die Myriopoden der ôster-reichisch-ungarischen Monarchie’ii, 1884. His treatment of the order Symphyla (pp. 1—18 and Taf. i) is a very important contribution : it contains a rather detailed description of the external structure, abstracts of earlier papers on some of the internal organs, notes on some larval stages, the best descriptions hitherto published of three European species, a sketch of the history of the systematic position of the group, etc. In reality it gives both a considerable addition to our knowledge, and abstracts of or reference to nearly all earlier scientific papers until 1882 touching the subject. I will therefore refer the student to Latzel’s book, and confine myself to a very short extract and a few remarks.
The Bionomics of Convoluta roscoffensis, with Special Reference to its Green Cells
Authors: Gamble F. W. , Keeble Frederick
Published: April 2021

Convoluta roscoffensis is a green Turbellarian peculiar to Brittany, along whose coasts it is distributed intermittently. It is a slender, elongated, ciliated worm of sedentary, gregarious habit.
Notes on Rhabdopleura Normani, Allman
Authors: Fowler G. Herbert
Published: April 2021

These notes, written mainly some years ago, did not seem worthy of publication by themselves. But my friend Mr. Harmer lately called my attention to some remarkable statements made by Messrs. Conte and Vaney1 which seem to justify the publication of the present paper, despite the small quantity and imperfect preservation of my materials.
On a New Species of the Genus Haplotaxis ; with some Remarks on the Genital Ducts in the Oligochæta
Authors: Benham W. Blaxland
Published: April 2021

Amongst the material collected by Mr. Keith Lucas during his biological survey of the New Zealand lakes I find two small worms belonging to the genus Haplotaxis, of Hoffmeister (= Phreoryctes, auctorum), which differ from the two species already known—H. gordioides, from Europe and America, and H. smithi, from New Zealand—in being provided with only a single pair of ovaries and oviducts. For this new species, therefore, I propose the name Haplotaxis heterogyne. Justification for placing the worms in this genus, hitherto characterised by the possession of two pairs of female organs, will be found below.
Two New Forms of Choniostomatidæ: Copepoda Parasitic on Crustacea Malacostraca and Ostrocoda
Authors: Hansen H. J.
Published: April 2021

During a stay—in August, 1902—in the house of my friend, the Rev. Canon A. M. Norman, I had the good luck to discover, in his splendid collection, a new parasitic Copepod on a couple of specimens of a rare Norwegian Amphipod. He asked me to work out the parasite, which I promised, and the result is given here.
The Epithelial Islets of the Pancreas in Teleostei
Authors: Rennie John
Published: April 2021

The question of the anatomical and functional nature of the islet-like groups of cells occurring within the pancreas of vertebrate animals has been studied by a large number of investigators since attention was first directed to them by Langerhans in 1869. These inquiries have for the most part been confined to the higher vertebrates, and summaries of their results have already been given by other writers (Laguesse, 1894; Oppel, 1900). Notwithstanding the somewhat extensive literature of the subject, there is so much disagreement as to the real nature of these bodies that further inquiry was desirable. Oppel (13) wrote in 1900, “Was die Bedeutung der intertubularen Zellhaufen anlangt, so ist dieselbe, so viel auch daruber geschrieben wurde and so viele Ansichten auch daruber bestehen, noch nicht ganz erklart.”
Observations on the Maturation and Fertilisation of the Egg of the Axolotl
Authors: Jenkinson J. W.
Published: April 2021

Eleven years have elapsed since the appearance of Rudolf Fick’s memoir on the fertilization of the axolotl; yet, in spite of the host of authors who have since dealt with this, the earliest moment of development, his paper still stands out as one of the completest studies of the behaviour of the spermatozoon in the egg.
On the Behaviour of the Nucleolus in the Spermatogenesis of Periplaneta Americana
Authors: Moore J. E. S. , Robinson L. E.
Published: April 2021

The present communication has arisen as a by-product of the work upon the reduction processes in animals and plants, upon which the authors have for some time past been engaged.
On Some Movements and Reactions of Hydra
Authors: Wagner George
Published: April 2021

This study of the movements and reactions of Hydra was undertaken at the suggestion of Professor H. S. Jennings, whose own researches (‘97—’02) on the reactions of protozoans have added new interest to this line of work.
On the Early Stages in the Development of Flustrella hispida (Fabricius), and on the Existence of a “Yolk Nucleus” in the Egg of this Form
Authors: Pace R. M.
Published: April 2021

In the following paper an attempt has been made to trace out the earlier stages in the development of Flustrella hispida. The larva of this familiar Bryozoan has previously been studied by Hincks (13), Redfern (22), Joliet (14), Barrois (2), and Prouho (20), but the first four authors studied only the living larva, of which Barrois has given an excellent account with numerous figures, while Prouho, who has described the later stages of the larval history in detail, has paid but little attention to its earlier stages.
On the Structure of the Nephridia of Dinophilus
Authors: Shearer Cresswell
Published: April 2021

Schmidt (22) was the first to draw attention to the nephridia of Dinophilus in 1848, which he simply mentions in D. vorticoides as two longitudinal vessels. They seem to have escaped further attention till Korschelt (11) in 1882 again mentioned their presence in D. apatris. It is to Harmer (8), however, that we owe the most complete description of the nephridia. In 1889 he described five pairs in D. tæniatus, a species found abundantly in the tidal pools of Plymouth Bay. Since then they have been studied by Schimkewitsch (23) in D. vorticoides from the White Sea. This last author investigated them by means of the intra vitam method of staining with methylene blue, but was able to add little to Harmer’s account of their structure.
The Structure, Development, and Bionomics of the House-fly, Musca domestica, Linn
Authors: Hewitt Gordon
Published: April 2021

In the present paper, which is the second of the series of three, the breeding habits and development of M. domestica and the anatomy of the mature larva will be described. Its publication has been delayed owing to the fact that I wished . to make the observations on the breeding habits and life history as complete as possible. With the recent appearance of two short papers by Newstead (1907) and Griffith (1908), many of whose observations, to which I shall refer later, are confirmatory of my own results, we now have a more complete account of the breeding habits of this insect.
Early Ontogenetic Phenomena in Mammals and their Bearing on our Interpretation of the Phylogeny of the Vertebrates
Authors: Hubrecht A. A. W.
Published: April 2021

In the present paper I have attempted to bring together the results of new investigations and recent reflexions with such as had already been published on earlier occasions, but which, having appeared in very different periodicals and publications (’89,’90,’94,’95,’96,’99,’02,’05,’07), could not be easily brought into the necessary connection with each other by the reader.
On the Occurrence of Nuclear Dimorphism in a Halteridium parasitic in the Chaffinch, and the probable connection of this parasite with a Trypanosome
Authors: Woodcock H. M.
Published: April 2021

In the course of an investigation on the Hæmatozoa of birds, undertaken as Mackinnon Student, I have recently observed certain forms which are of great importance in reference to Schandinn’s view of the ontogenetic relationship between a Trypanosome anda Halteridium of the “Little Owl.”
Some Observations on Acinetaria
Authors: Martin C. H.
Published: April 2021

Part I.—The “Tinctin-korper” of Acinetaria and the Conjugation of Acineta papillifera.
Physiological Degeneration and Death in Entamæba ranarum
Authors: Dobell C. Clifford
Published: April 2021

In the following pages, I wish to call attention to some remarkable events which I have observed in the life-history of Entamœba ranarum Grussi, an organism which I have been studying for some time, and whose life-cycle—so far as I had succeeded in following it—I have already described in a previous paper (2). I will divide my remarks into two sections —I, a description of the phenomena actually observed, and II, a discussion of their significance.
The Structure of Trypanosoma lewisi in Relation to Microscopical Technique
Authors: Minchin E. A.
Published: April 2021

Much has been written of late years about the minute structure of trypanosomes, and also about the merits or demerits of the various methods in vogue for preparing them for examination with the microscope, that is to say, the technique of fixing, staining, and preserving these tiny creatures. Since our knowledge of the structure of trypanosomes is based almost entirely on the results of a number of complicated chemical and physical processes practised on a very delicate protoplasmic body, it is clear that a knowledge of the effects produced by these processes on the organisms are most important in interpreting the microscopic image finally obtained, in order to estimate, in any given case, how far the trypanosome may have undergone deformation or change as the result of the treatment it has gone through. In a perfect state of scientific knowledge it would, no doubt, be possible to deduce exactly such results from the known action of the reagents employed upon the protoplasmic body, but in the present condition of our knowledge it is only possible to arrive empirically at an approximate estimate of the effects of technique by comparing carefully the results yielded by it.
Intra-cellular and General Digestive Processes in Planariæ
Authors: Arnold G.
Published: April 2021

In 1878 Metschnikoff drew attention to the phenomena of intra-cellular digestion occurring in Turbellarian worms. Since that time but little has been published dealing with this very interesting subject.
The Structure, Development, and Bionomics of the House-fly, Musca domestica, Linn.: Part III.—The Bionomics, Allies, Parasites, and the Relations of M. domestica to Human Disease
Authors: Hewitt C. Gordon
Published: April 2021

The present paper concludes this study of the structure, development, and bionomics of Musca domestica (the previous parts were published in 1907 and 1908). In it I have described the bionomics, certain of its allies which may occur in houses, its parasites, and its relation to man, especially as the carrier of the bacilli of certain infectious diseases.
Studies in the Experimental Analysis of Sex
Authors: Smith Geoffrey
Published: April 2021

During my occupation of the British Association Table at Naples this winter I took the opportunity of re-examining certain points connected, with the effect of Sacculina neglecta on the spider-crab Inachus mauretanicus, with the especial purpose of trying to settle the exact way in which the gonad of infected individuals degenerates and is absorbed. The mid-winter months being the most favourable season-at Naples for finding numerous individuals of Inachus very profoundly modified by the presence of the parasite, I was able to re-invéstigate many crucial stages in the modification of the external and internal sexual organs, with the result that, while certain new facts of interest have come to light, I see no reason whatever for departing in any respect from the statement of facts made in my earlier work, or from the deductions drawn from them (‘Naples Monograph,’ No. 29, Chap. V). In this paper, besides giving the results arrived at in respect to the degeneration of the gonad, I propose to describe certain new instances of infected Inachus which afford incontestable proof that male crabs with differentiated though reduced male internal organs can assume all the adult female secondary sexual characters. It will also be shown both for the male and female sex that the effect of parasitic castration can on no account bé interpreted as a return to a juvenile undifferentiated condition.
On the Anatomy of Histriobdella Homari.’
Authors: Shearer Cresswell
Published: April 2021

Our knowledge of the anatomy of Histriobdella is based on the papers of Van Beneden (1858), Foettinger (1884), and Haswell (1900). Of these, Foettinger’s account is the most extensive, while Haswell’s paper is perhaps the most valuable. Both accounts contain a more or less detailed description of the internal structure and organisation of the adult. Several years ago I described the presence of solenocytes in connection with the nephridia of Dinophilus. This discovery rendered it probable that these peculiar structures would also be found in Histriobdella, with which Dinophilus shows many relationships. Moreover, the different description of the nephridial system given by Haswell in Stratiodrilus from that of Foettinger for Histriobdella called for a re-investigation of these organs. For these reasons the present work was begun. I was soon led to undertake a detailed examination of the animal. It is some twenty-five years since the publication of Foettinger’s paper, and during this interval the European species of Histriobdella has received no further attention. In the following account I have endeavoured to clear up Foettinger’s description of several of the organs. I have had the advantage of having made use of the methyl-blue method of intra vitam impregnation, which has proved most valuable. With its use I have experienced no difficulty in determining the number of the nephridia and their relationship to the segments, and to make out new details in their structure quite impossible from ordinary sections of fixed material.
Studies on Avian Hæmoprotozoa. I. On certain Parasites of the Chaffinch (Friagilla cœiebs) and the Redpoll (Linota rufescens).I
Authors: Woodcock H. M.
Published: April 2021

My reason for taking up the study of Avian Hæmoprotozoa has been the desire to obtain, if possible, some definite enlightenment on the important question of their life-cycle. The far-reaching conclusions bearing upon this subject, to which the celebrated protozoologist, the late Fritz Schaudinn, was led as the result of his well-known researches (27) on certain parasites of thelittleowl (Athene noctua), have been largely discredited by many subsequent workers in this field. This is chiefly due to the suggestion, first put forward by the American workers, Novy and McNeal, that there is nothing in Schaudinn’s description to show that the author took sufficient precaution against the liability of confusing the lifehistories of what were really separate and independent parasites. Novy and McNeal, in their endeavour to confirm Schaudinn’s views, investigated the trypanosomes of various birds (14), and also made a study of the flagellates occurring naturally in mosquitoes (15). As a result of their work they have maintained that Schaudinn was entirely wrong in regard to all his main conclusions. They consider, on the contrary, that the trypanosomes of birds are quite distinct from intra-cellular parasites (such as Halteridium), and further, that they do not undergo any part of their life-cycle in an insectan host, the flagellates occurring in the latter having no connection with the trypanosomes.
Studies on Ceylon Hæmatozoa. No. II.—Notes on the Life-Cycle of Hæmogregarina nicoriæ, Cast, and Willey
Authors: Robertson Muriel
Published: April 2021

In 1904 Drs. Castellani and Willey (3) described a hæmogregarine from the blood of the common lake-tortoise of Ceylon, Nicoria trijuga. They named the parasite Hæmogregarina nicoriæ after its host. Shortly afterwards these authors gave a somewhat fuller account of their observations in the’ Quarterly Journal of Microscopical Science’ (4).
On the Origin and Migration of the Stinging-Cells in Craspedote Medusæ
Authors: Boulenger Charles L.
Published: April 2021

Lewis Murbach (1), in 1894, definitely established the fact that the stinging-cells of the Hydromedπsæ have the power of active movement in the tissues by the formation of pseudo-podial processes from the cnidoblasts.
On the Morphology of the Cranial Muscles in Some Vertebrates
Authors: Edgeworth F. H.
Published: April 2021

In the following paper I have described and compared the development of some of the cranial muscles in Scyl-lium canicula, Squalus acanthias, Acipenser sturio, LepidoSteus osseus, Amia calva, Salmo fario, Cera-todus Forsteri, Triton cristatus, Rana temporaria, Alytes ohstetricans, Bufo lentiginosus, Pelobates fuscus, Chrysemys marginata, Lacerta agilis, chick, rabbit, and pig.
A Monograph of the Tape-worms of the Subfamily Avitellininæ, being a Revision of the Genus Stilesia, and an Account of the Histology of Avitellina centripunctata (Riv.)
Authors: Henry Gough Lewis
Published: April 2021

The following paper was commenced at Leeds; it was originally intended only to give an account of the anatomy of Stilesia hepática, Wolffhügel, which has been very imperfectly known until now, as much of the original description is not only incorrect but actually misleading. That section of this paper treating of Stilesia hepática, Wolffhiigel, was prepared at Leeds. I am much indebted to Prof. Garstang for his hospitality in placing his laboratory at my disposal and for the encouragement I received from him, and desire to express my thanks to him for it here.
Brief Notes on the Structure and Development of Spirochæta anodontæ Keysselitz
Authors: Bosanquet W. Cecil
Published: April 2021

Much uncertainty still prevails as to the structure and biological relationships of the spirochætes. Earlier observers —not altogether influenced perhaps by a desire to prove their affinities with the hæmoflagellates—equipped them with an undulating membrane and a complicated nuclear apparatus, the existence of which is very problematical; and much controversy has existed as to their mode of division, longitudinal or transverse. The very claim of the organisms found in Mollusca, as well as that of the smaller spirochætes, to be called by this name, depending as it must on their relationship to Sp. plicatilis Ehrenberg, the type-species, is not very firmly established, since the structure of the latter—a system of large waves, each broken by smaller undulations superposed on them, with a central axial rod and a series of dots, regarded as nuclei—is markedly different from that of the later additions to the genus. It is desirable, therefore, to record any observations which may tend to throw light on the morphology and life-history of these organisms.
Note on the Mechanism of Discharge of the Cuvierian Organs of Holothuria nigra
Authors: Mines George Kalpli
Published: April 2021

It is well known that when Holothuria nigra (the large sea-cucumber common at Plymouth) is irritated, it responds by emitting a number of white conical bodies. These, the Cuvierian organs, rapidly elongate, shooting through the water while remaining attached at their bases to the animal, to form long, intensely sticky tubes. The phenomenon has been described by Minchin (1), Barthels (2), Herouard (3) and others, but there appears to be much divergence of opinion as to the mechanism by which the elongation of the tubes is brought about. Herouard ascribes it to the forcible injection of the tubes with water, while Minchin denies that water-pressure plays any part in the discharge, and attributes the whole affair to the intrinsic activity of the organs themselves. The latter view is adopted by Sedgwick (4).
On the Histological Structure of the Retina of the Lateral Eyes of Sphenodon punctatus, with Special Reference to the Sense-cells
Authors: Rage Freda
Published: April 2021

The following work on the structure of the retina in the lateral eyes of Sphenodon punctatus has been done in the Zoological Department at King’s College (University of London), at the suggestion and with the help of Professor Dendy. I have to thank him both for his help and advice throughout, and for the use of his valuable collection of Sphenodon material. I have not only had a considerable number of eyes at my disposal, but I found them in an excellent state of preservation for histological work. I should like here to thank, also, Mr. R. W. H. Row, B.Sc., for his kindness in taking photographs. The investigations are based entirely on microscopical preparations made from this already preserved material. No fresh material has been available, and for this reason I have found it advisable to confine the detailed work for the most part to the structure of the visual cells, dealing, as regards the remainder of the retina, only with those parts which are visible without special treatment for nerve-fibres.
The Structure and Development of Reissner’s Fibre and the Sub-commissural Organ.
Authors: Nicholls George E.
Published: April 2021

In October, 1907, when working in the Zoological Laboratory of the Imperial College of Science and Technology, I undertook, upon the suggestion of Professor Dendy, an investigation into the structure known as Reissner’s fibre. Since January, 1908, the work has been carried on in the Zoological Department at King’s College (University of London).
Transverse Segmentation and Internal Differentiation of Chromosomes
Authors: Agar W. E.
Published: April 2021

The material for this paper was partly the same as was used for my former paper on the spermatogenesis of Lepidosiren, partly Lepidosiren larvæ obtained during the same expedition, and partly larvæ collected by Prof. Graham Kerr on his previous expedition to the Paraguayan Chaco.
The Life-Cycle of Moina rectirostris
Authors: Grosvenor G. H. , Smith Geoffrey
Published: April 2021

In the summer of 1904 the late Mr. G. H. Grosvenor began some experimental observations on the life-cycle of Moina, with the object of testing Weismann’s hypothesis (1) that the succession of parthenogenetic and sexual individuals is controlled by an internal rhythm independently of external circumstances. The species of the genus Moina, as pointed out by Weis man n, belong to the polycyclic group of Cladocera which inhabit small ponds and which produce sexual individuals with great frequency, and this fact, together with the ease with which they can be cultivated, renders them convenient for experimental purposes.
Changes in Chondriosomes Occurring in Pathological Conditions
Authors: Wakelin Barratt J.O.
Published: April 2021

The structural characters of chondriosomes were first investigated in detail by Benda1 in a number of different cell types (renal cells, spermatids, marrow cells, leucocytes, striated muscle).
The Development of Symbranchus marmoratus
Authors: Taylor Monica
Published: April 2021

The Symbranchii are a, small group of eel-like fishes which are generally placed near the Apodes in recent systems of classification, though lack of sufficient anatomical description and embryological material has made it difficult to determine exactly their affinities. Tate Regan, in his “Anatomy and Classification of the Symbranchoid Eels” (9), derives them from the Acanthopterons physoclists. The embryology of a Symbranchid has, up till now, not been investigated.
Studies on Parasitic Protozoa. II (a) The Encystment of Rhizomastix gracilis Alexeieff; (b) Tetratrichomastix parisii n. sub-gen., n. sp
Authors: Miickimion Doris L.
Published: April 2021

The intestine of that common grub, the larval Tipula, contains a rich bacterial flora, at the expense of which there flourish a surprising number of protozoa.’ Among these are at least eight flagellates and two amoebte.1
The Gregarines of Glycera siphonostoma
Authors: Pixell-Goodrich Helen L. M.
Published: April 2021

The large Polychaet, Glycera siphonostoma D. Ch. (sometimes placed in a separate genus Rhynchobolus), is at times infested with numerous gregarines, both intestinal and coelomic. On this account it is somewhat difficult to differentiate the stages in the life-history of anyone of them. Out of fifty-two specimens examined at Naples in March and April, 1914, twelve (I to IX, XII, XIV, and XXVI) were infected with a species of Gonospora which presented some interesting points. The affinities of this form with previously established species will be discussed later. It does not agree in detail with the published account of any, notwithstanding the fact that Léger (11) has already recorded Gonospora sparsa as occurring in some undetermined species of Glycera at Belle Isle.
On the Development and Morphology of the Pharyngeal, Laryngeal, and Hypobranchial Muscles of Mammals
Authors: Edgeworth F. H.
Published: April 2021

This paper is a continuation of one published in this Journal (1914, vol. 59) on “The Development and Morphology of the Mandibular and Hyoid Muscles of Mammals.” It deals with the structure of the pharyngeal, laryngeal, and hypo-branchial muscles of Ornithorhynchus and Echidna, with the development of these muscles in Dasyurus viverrinus and some other Marsupials, in the pig and rabbit. The last few pages contain a summary of the similarities and differences between the cranial muscles of Monotremes, Marsupials; and Eutheria.
The Early Development of the Spleen of Lepidosiren and Protopterus
Authors: Purser G. L.
Published: April 2021

My first words must be those of thanks to Professor Graham Kerr for providing me with every facility for carrying out the research, the results of which are embodied in this short paper. He invited me to work in his laboratory, provided me with material already stained and mounted, and was especially helpful in suggestion and criticism.
A Note concerning the Collar Cavities of the Larval Amphioxus
Authors: Smith K. M. , Newth H. G.
Published: April 2021

Notwithstanding the great volume of literature dealing with the development of Amphioxus, there are many points still outstanding on which the light of further investigation must he thrown. The present short communication attempts to dispose of one of these.

It is well known that in Amphioxus the cavities of the typical somites give rise, on the one hand, to all the myocœls except the first pair, and, on the other hand—by the fusion of their ventral moieties on each side—to longitudinal spaces which are the splanchnocœls. But the fate of the so-called “collar cavities” has not hitherto been satisfactorily established. It was known that from the walls of their dorsal parts were formed the first pair of myotomes; but there has been difference of opinion about the behaviour of their ventral parts.
The Cytoplasmic Inclusions of the Germ-Cells: PART I. LEPIDOPTERA
Authors: Brouté Gatenby J.
Published: April 2021

(1) In Smerinthus populi, Pieris brassica), and a number of other species of moths and butterflies the cytoplasmic bodies have been followed out.

(2) The micromitosome has been followed from the spermatocyte back into the secondary spermatogonium. It is very probably present in the primordial germ-cell.

(3) The micromitosome has been definitely found in the female.

(4) The micromitosome seems to divide in all divisions, and I consider that it is a constant factor in the spermatids of Smerinthus.

(5) The probable nature and function of the micromitosome is discussed.

(6) The mitochondria have been carefully’ examined in the male and female germ-cell in all stages except in the maturation division of the female and in fertilisation.

(7) It has been shown that in early stages the cytoplasmic bodies of the female resemble those of the male.

(8) There is a definite period, judged to be about the beginning of growth stage, when the subsequent fate of the mitochondria in the male becomes different from that of tlm female.

(9) The remarkable formation of chromophobe and chromophile zones in the male mitochondrial body and the use of these zones are described.

(10) The formation of the macromitosome from the mitochondria is described.

(11) The changes undergone by the macromitosome in sperm formation are followed out.

(12) The presence of the acroblasts in the fairly early growth period of the spermatocyte is described.

(13) The complicated evolutions of these bodies in division of the cells, their subsequent fate and’ their probable nature are discussed.

(14) The staining and fixing reactions of the cytoplasmic bodies are fully described.

(15) A number of abnormalities have been described.

(16) The centrosome has been shown to divide in the young spermatid, and one centrosome is probably lost, but definite evidence is not forthcoming.
On Oxnerella maritima, nov. gen., nov. spec., a New Heliozoon, and Its Method of Division; with Some Remarks on the Centroplast of the Heliozoa
Authors: Dobell Clifford
Published: April 2021

In 1913 I found a minute and pretty heliozoon in some small tanks of sea-water in which I had been cultivating Foraminifera, Trichosphaerium, and other marine Protozoa. For some weeks the organisms multiplied rapidly and became very abundant. I studied them alive as carefully as possible, and made a number of fixed and stained preparations in order to study their method of division in detail. I also made a number of notes and drawings at the time, but was too much occupied with other work to set them in order for publication. As the organisms seem not to have been described hitherto, and as their division presents certain features of interest, I now take the opportunity of putting my observations on record.
Note on an Amœba-like Parasite from Clavellina
Authors: Huxley Julian S.
Published: April 2021

In the summer of 1910 at Naples I noticed that the stomach of small (and therefore semi-transparent) individuals of the social Ascidian, Clavellina lepadif ormis, sometimes contained a number of solid objects. When this was so it was obvious, because the ciliary action in the stomach kept these objects in constant and rapid motion.
On the Occurrence of Protohydra in England
Authors: Hickson Sydney J.
Published: April 2021

The Protohydra leuckartii is a minute, solitary hydro-zoon (about 3 mm. in length when fully extended), entirely devoid of tentacles and known to increase rapidly in numbers by simple transverse fission.
On the anatomy and affinities of Paludestrina ventrosa, Montague
Authors: Robson Guy C.
Published: April 2021

Paludestrina ventrosa possesses the general Taenioglossate organization. It represents a genus of Paludestrinidae equivalent to Bythinella and Vitrella. It is peculiar within the family as possessing: Folded gills; A slit connecting the style sac through nearly all its length with the intestine ; A typhlosole; A non-ciliated roof to the median part of the pharynx. It represents an intermediate stage in the acquirement of the fresh-water mode of life, being essentially a brackish-water form with a fairly well-marked euryhaline tendency. Several structures not fully described by previous authors are discussed in this paper (e.g. the accessory female and circulatory organs), and it is not certain in what form these structures occur in other Taonioglossa. Within the Order Taenioglossa, Paludestrina is referable to the group which possesses : a brevicommissurate visceral commissure ; a single otolith ; an osphradium with basal ganglion ; a renal-portal system and blood-gland ; an ‘oviducal’ gland immediately adjacent to the receptaculum seminis.
A further Account of the Spermatogenesis of Lice
Authors: Cannon H. Graham
Published: April 2021

In 1919 the late Professor Doncaster and the present author investigated the gametogenesis of the lice Pe die ulus corporis and Pedieulus capitis. An account of this work was published during the following year (3). The cytology of the spermatogenesis was found to be so peculiar and in some respects unique, that it was decided to extend the work to other lice. At the time of his death Professor Doncaster was working on the gametogenesis of the horse-louse and the doglouse. The material collected by him together with his notes was handed over to me by Professor J. Stanley Gardiner.
Observations upon the Behaviour and Structure of Hydra.
Authors: Marshall Sheina
Published: April 2021

The Hydras upon which the following observations were made were obtained from various sources, chiefly through the kindness of Dr. Monica Taylor, from the Convent of Notre-Dame. They were kept in covered, half-pint glass tumblers, in water from a large tank in which there was a fair quantity of weed and a variety of animal life (Isopods, Cladocerans, Planarians, &c.). This was used because the Hydra would not live for more than one or two days in tap-water. The water was-changed and the tumblers cleaned when necessary. This was about once a week in summer, as food-remains became foul very quickly then, but less frequently in winter. The water was never aerated artificially. The Hydras were fed on a culture of Daphnia twice a week, and the remains and excreta removed, as far as possible, the following day. Under these conditions the Hydras lived and remained healthy for months. Occasionally one or two, for no apparent reason, would decrease in size and finally degenerate and die, but in only one case was a whole tumbler attacked by a ‘depression period Even here a fair proportion remained healthy throughout. When well fed the Hydras budded actively. None of my specimens carried more than four or five buds at a time and the number was usually less.
Contributions to the Study of the Development of the Head in Heterodontus
Authors: Beer G. R. de
Published: April 2021

The development of the skull of Heterodontus is described. There is no trace of an otic process. The tectum synoticum forms after the more anterior roofing. The efferent pseudobranchial artery is from the first dorsal to the trabecula. The afferent pseudobranchial artery is not the mandibular artery. Longitudinal bands of cartilage exist along the notochord but are probably not primary. The dorsal and ventral roots have moved forwards so as to be enclosed in cartilages. The olfactory nerve is subdivided into two, which subdivisions do not correspond with the subdivisions of the olfactory sac. The neural crest contributes to the terminalis, which shows one ganglion.
On the Development of the Male Genitalia and the Efferent Genital Ducts in Lepidoptera
Authors: Raj Mehta Dev
Published: April 2021

A general account of the internal reproductive organs and the external genitalia and their development is given.

The ‘penis lobes’ develop earlier than the ‘valvae lobes ‘, and independently of them.

The tegumen is the modified ninth tergite. The tenth segment is visibly distinguished into a tergal and sternal part in the pupal stages, and the anal tube passes between the two sclerites. The uncus and the gnathos are dorsal and ventral processes respectively of the tenth segment. The anellus lobes develop as lateral processes of the ninth sternite on either side of the penis.

The vasa deferentia during larval life do not extend beyond the eighth abdominal segment and lie in a latero-ventral position. They meet the extensions from the ectodermal ‘ductus ejaculatorius duplex’ during the last larval stadium.

From the earliest caterpillar stage there exists a pair of ectodermal ducts formed by the differentiation of the epidermis on the ninth sternite. Towards the end of larval life they divide by constriction to form the accessory glands and the ‘ductus ejaculatory duplex’. At this stage they extend on either side to meet the vasa deferentia.

The vesiculae seminales develop by distension from the region of junction between the vasa deferentia and the proximal portion of the ejaculatory duct.

The ‘ductus ejaculatorius simplex’ arises as an ectodermal invagination between the pair of ‘penis lobes ‘during the final larval instar.

It is established that, with the exception of the vasa deferentia, all the remaining elements in the efferent genital system are derived from the ectoderm.
Notes on the Structure and Development of the Female Genital System in Dasyneura leguminicola Lint. (Cecidomyidae-Diptera)
Authors: Metcalfe Margot E.
Published: April 2021

Genitalia of an appendicular nature are absent in D. leguminicola, the terminal abdominal segments being modified to form a tubular retractile ovipositor. Apart from the ovaries and a portion of the paired oviducts, the efferent system is unpaired and ectodermal in origin. The gonopore is posterior to the ninth sternite, and is derived from the primitive spermathecal invagination as in the Coleoptera. The uterine rudiment is present during the early stages of development, but later becomes closed over, discharging its contents into the duct derived from the spermathecal rudiment.
The Formation of Melaniridosomes in healing wounds of Haemulidae
Authors: Smith George Milton
Published: April 2021

The earlier studies of the pigment cells of fishes by v. Siebold (1863), Pouchet (1876), Leydig (1895), were followed by a long series of important investigations by Ballowitz (1893-1924) upon which a large part of our present knowledge of the complicated morphology of the teleost skin rests. More recently, information on this subject has been extended by the work of Kurz (1920), Becher (1924), Schnackenbeck (1925), Kann (1926), Jost (1926), Panu (1929), Graupner and Fischer (1933).
Note on the Behaviour of certain Cell Inclusions during Mitosis in Tenthredinidae.
Authors: Peacock Professor A. D. , Greenshields F.
Published: April 2021

Four conspicuous rounded bodies, lying symmetrically disposed, one on the surface of each quadrant of the spindle, have been found during the metaphase of blastoderm cells developed from the partheno-produced (male) eggs of Thri-nax mixta, a parthenogenetically arrhenotokous species of Tenthredinidae. During the process of cell division they ultimately form a single mass in a position formerly occupied by the centre of the spindle, and the material composing this mass streams out towards either pole and appears to be more or less equally shared between the two daughter cells. The movements of the inclusions appear to be due to changes in the form of the spindle. Their fate is unknown, as is their function. Such bodies and their behaviour do not appear to have been recorded before, but in certain respects they behave like aggregations of thread-like cell inclusions in Stenobothrus lineatus which Bělařcalls mitochondria; that they are mitochondrial is suggested from the technique which revealed them. It is suggested that such bodies might easily be mistaken for sex chromosomes.
Cleavage of Blastomeres in the Absence of Nuclei
Authors: Gross F.
Published: April 2021

In the following pages a brief account is given of observations which touch upon two much discussed problems: (1) are eggs or blastomeres capable of division if deprived of the nucleus? (2) are divisions of blastomeres in the absence of chromosomes and spindles to be regarded as cleavage, and the product resulting from the divisions as corresponding to stages of normal development, in this case, to a blastula?
On the Occurrence of Living Forms in the Hot Waters of California
Authors: Edwards Arthur Mead
Published: April 2021

In the May (1866) number of the ‘American Journal of Science’ were some notes by Prof. Brewer on the occurrence of living forms in the hot and saline waters of California, in which a slight error appeared, tending to mislead naturalists more particularly with regard to certain observations of mine. In the subsequent number for November Prof. Brewer inserted a note making a correction in this matter, but, as the subject is one of importance, I have taken the liberty of putting together a few notes relating thereto, and beg of you to insert them at your convenience.
Notes on some Algæ from a Californian Hot Spring
Authors: Wood H. C.
Published: April 2021

Some time since Professor Leidy handed me for examination a number of dried Algæ, which he had received from Professor Seidensticker, by whose sister, Mrs. Partz, they had been gathered in the Benton Spring, which is situated in the extreme northern point of Owen’s Valley, California, sixty miles south-west from the town of Aurora. Afterwards a number of similar specimens came to me directly from Mrs. Partz by mail. The subject of life in thermal springs is one of so much general interest, especially in connection with that of spontaneous generation, as to induce me to make a very careful examination of the material and offer the results to the readers of this journal. In this connection the following extract from a letter of Mrs. Partz to her brother is very relevant:
A Quantitative Study of the Changes in the Cyto-some of Eggs of the Echinodermata during Early Cleavage
Authors: Pelluet D.
Published: April 2021

An estimate of the changes in volume, fat, and mitochondria occurring in the early cleavage stages of Arbacia has been made. The volume fluctuates with each successive cleavage, but it is probable that there is no significant change until after the gastrula stage has been reached.

The number of fat-granules decreases steadily from the unfertilized to the four-cell stage, with a slight increase in the blastula.

The mitochondria show a slight decrease between the unfertilized and fertilized condition and a marked decrease at the four-cell stage, followed by a sharp increase in the blastula.

A preliminary investigation of another Echinoderm, Asterias forbesi, suggests that it differs considerably from that of Arbacia.

It is a pleasure to acknowledge the assistance of Dr. F. R. Hayes in several ways, and especially for checking many of the calculations.
The Direct Development of a New Zealand Ophiuroid
Authors: Fell H. Barraclough
Published: April 2021

The first cleavage may be either equal, or markedly unequal; when it is equal the next segmentation affects both blastomeres ; when it is unequal the larger blastomere is believed to give rise to three cells, and the smaller remains undivided till the next cleavage. At the eight-cell stage there are two quartets of blastomeres. The upper quartet, micromeres, occupy the animal pole. The lower quartet, macromeres, occupy the vegetal pole. The blastula comprises micromeres and macromeres, and the blastocoel is small and becomes eccentric. No cilia are developed. The gastrula is formed by the shallow invagination of the macromeres, accompanied by an extensive process of epiboly affecting the micromeres. More marked epiboly of cells on two sides of the blastomere produces in the early stages two crests which later disappear. These may indicate a trace of bilateral symmetry. Epiblast comes to lie on solid mes-hypoblast. The archenteron is transient, and gives rise to no structures. The blastopore occupies the position of the definitive mouth. No larva ever forms, nor is there any vestige of a larval stage. The solid gastrula is converted into the adult by assuming a radial symmetry directly, with no intermediate bilaterally symmetrical form, unless the two epibolic crests are regarded as vestiges of larval symmetry. The podia appear as solid outgrowths, in which the hydrocoelic cavity develops by splitting. The definitive enteron appears as a split extending upward from the ventral surface through the solid hypoblast. The young ophiuroid leaves the egg before the appearance of the general body cavity, and moves about, but does not at first take food. The general coelomic body cavity and the perihaemal cavity develop by splitting in a mass of mesenchyme derived from the outer layers of mes-hypoblast. The formation of the skeletal system is delayed till the stage of between two and three arm-segments. The development of the skeleton follows closely that described for Amphiura squamata. The tooth is shown to originate independently of the torus angularis; its rudiments comprise nine symmetrically disposed spicules. The terminal plate arises later than the radials, and has a distinctive ‘primitive structure’. The spine is shown to have a different development to that of the tooth, and therefore would seem to have no connexion with the latter in phylogeny or ontogeny. It is suggested that the aberrant early stages are to be correlated with the retarding effect of the yolk mass present in the egg during ontogeny. The aberrant features may have had a different origin in phylogeny. It is suggested that the simultaneous appearance in ontogeny of homologous organs situated at equal radial distances from the centre is to be explained in terms of hormonie activity. It is concluded that evolution has considerably affected the early ontogeny without leaving its mark on phylogeny. The adult thus conforms to its class, the young form does not.
The ‘Dorsal Organ’ of the Embryo of Campodea
Authors: Tiegs O. W.
Published: April 2021

In his well-known work on the embryology of apterygote insects, written over forty years ago, Uzel recorded the presence of a ‘dorsal organ’ in the embryo of Campodea staphylinus. It was described as a circular thickening of the provisional body-wall, located in a median dorsal position immediately behind the developing head, but devoid of any very distinctive structural features. Like the problematical ‘dorsal organ’ (pre-cephalic organ) of collembolan embryos it was found to be a purely embryonic structure, and disappeared without a vestige before the larva left the egg. Its function was unknown.