bluuebunny/crossref_metadata_2025 huggingface dataset:
Notes on Hanstein’s Researches on the Development of the Embryo in Monocotyledons and Dicotyledons (Die Entwicklung des Keimes der Monokotylen und Dikotylen, von Dr. Johannes Hanstein, ‘Botanische Abhandlungen, Heft 1)
Authors: McNAB W. R.
Published: April 2021

In Cryptogams the tissues at the growing-point of a stem or root always form by division from a single apical cell. Hanstein, in his researches on the development of the tissues at the growing-point of the stem of Phanerogams, found that the tissues were developed, not from a single apical cell, as in Cryptogams, but from a tissue of similar cells. In only two cases did he trace back the development to the embryo in the seed. The question, therefore, still remained to be answered as to when the separation of the different meristem layers took place in the embryo, and whether the cells formed from a tissue or a single apical cell.
On the Disappearance of the Primitive Groove in the Embryo Chick
Authors: Balfour F. M.
Published: April 2021

The investigations of Dursy (‘Der Primitivstreif des Hühnchens,’ von Dr. E. Dursy. Lahr, 1866) on the primitive groove, showing that it is a temporary structure, and not connected with the development of the neural canal, have in this country either been ignored or rejected. They are, nevertheless, perfectly accurate ; and had Dursy made use of sections to support his statements I dó not think they would so long have been denied. In Germany, it is true, Waldeyer has accepted them with a few modifications, but I have never seen them even alluded to in any English work. The observations which I have made corroborating Dr. Dursy may, perhaps, under these circumstances be worth recording.
On the Crystals in the Testa of the Elm (Ulmus suberosa, Ehrh.), and the Character of the Epidermis of the Tway-Blade
Authors: Gulliver George
Published: April 2021

During the month of May the fruit of the elm is shed and scattered in profusion on the ground, often so as to make patches in OUT paths. Each fruit is a capsule, of a pale green colour, somewhat oval or rounded, very fiat, and about as big as the thumb-nail. The seed is contained near the centre of this compressed and winged capsule or samara, and the outer coat of the seed is the seat of the crystals. Every cell of this part contains a short, brilliant crystal, in form cubical, lozenge-shaped, or prismatic ; sometimes flattened parallelograms, rarely either single or double octahedrons, or twins like certain crystals of gypsum. Their mean diameter is about th of an inch. They are so firmly imbedded in the tissue as to be separable from it with difficulty ; this may be overcome by macerating the capsule in water until the tissue becomes pulpy from putridity, when the crystals may be isolated, and made to rollover in the microscopic field of vision.
On Diatomaceæ from Spitzbergen
Authors: O’meara E.
Published: April 2021

The collections which are the subject of the present paper were made by Rev. A. E. Eaton, who went out to the Arctic Sea in Mr. Leigh-Smith’s yacht. They consisted, 1st, of some stones coated with mucor, in which no diatoms were found; 2nd, of several bottles of various size. Of these a large number had unhappily been broken in the conveyance and the contents lost except the material that remained attached to the surface of the glass. This material was carefully examined, but not a single diatomaceous frustule appeared to requite the labour, so that it may be inferred that no loss was sustained by the casualty. Of the bottles which came uninjured one was rich in forms, the others contributed only a few to the general result. 3rd, of a large package of a very miscellaneous nature, made up of broken shells, pieces of seaweed, sand, and such like; its general appearance was not encouraging, nevertheless it yielded forms of sufficient number, variety, and interest, amply to requite the labour of preparation.
Description of an Apparatus for Maintaining a Constant Temperature under the Microscope
Authors: Schäfer E. A.
Published: April 2021

The necessity of having the means of conveniently, but at the same time accurately, maintaining objects, especially the living tissues, under observation at a uniform temperature (generally that of the body) becomes more obvious every day. The existing methods of effecting this are, as a rule, not sufficiently accurate for exact investigations; and, on the other hand, the more accurate modes are frequently in-convenient of application. For example, the apparatus described by Stricker and Burdon-Sanderson in this Journal for 1870,—although it is possible by its aid to maintain a constant temperature under the microscope for a considerable time,—yet requires that there should be a vessel of water constantly boiling near the observer, and that the water in this vessel should be maintained at a uniform level, necessitating a supply tube from a cistern, and an overflow tube to a waste pipe. Moreover, since the temperature of the stage is regulated by the rate at which the heated water is allowed to flow through it, and this again is made to depend upon the difference of level between the orifice of the exit tube which leads from the stage and the height of the boiling water in the reservoir, and since this requires a rather complicated screw mechanism accurately to adjust the level for different temperatures (not to mention the numerous india-rubber tubes requisite for connecting the various parts of the apparatus), it is evident that, although the apparatus in question may be well enough adapted for a laboratory, it is less applicable to individual and private work. The apparatus to be here described, the main principles of which are a constant circulation of water and the introduction of a gas regulator, will, it is believed, be found simple and convenient in application, and capable of maintaining with almost absolute constancy any desired temperature for an indefinite time.
On the Chronispores, or Chronizoospores of Hydrodictyon, and on some Analogous Reproductive Bodies
Authors: Pringsheim M. N.
Published: April 2021

It must be remarked that there are two sorts of zoospores formed in the polyhedrons—large and small, (figs. 18 and 19) —differing in size as much as those zoospores do that are produced in the cells of the retiform Hydrodictyon, some of which unite into a network, while the smaller ones always remain separate. On the contrary, in the polyhedrons all the zoospores are united in a retiform manner; the meshes of those formed from the smaller ones being more numerous and narrower.
On the Embryo-sac and Development of Gymnadenia Conopsea
Authors: Ward H. Marshall
Published: April 2021

The hitherto received account of the origin, mode of formation, and homologies of the embryo-sac in Angiosperms was based on the researches of Hofmeister,1 for the most part, and may be summed up to the following effect :—A single cell situated in the apical part of the nucleus, and usually the foremost of an axial row, enlarges, its nucleus disappears, and a variable small number of free nuclei appear in the protoplasm by free cell formation. Of these, two are close to the apex of the enlarged cell, and are known as “germinal” or “embryonic” vesicles, while a very inconstant number of “antipodal” cells often, but not always, forms in the lower end of the protoplasm. The enlarged cell is the embryo-sac, and receives the pollen tube at its apex, where one, or at times two, of the germinal vesicles become fertilised by the contents of the tube. Schacht 2 showed that one of the germinal vesicles acted as a conductor between the tube and the fertile vesicle, or that two acted as such towards a third germinal vesicle, and were often marked by peculiar longitudinal striæ.
On Certain Effects of Starvation on Vegetable and Animal Tissues.1
Authors: Cunningham D. D.
Published: April 2021

That insufficient supply of nutritive material is closely connected with fatty degeneration of tissue is a well-ascertained pathological phenomenon. Rindfleisch, in his work on ‘Pathological Histology,’ expresses himself as follows in regard to this subject:—“This (the exclusively pathological category of fatty metamorphosis) includes all cases of disproportion between the means of nutrition and the parenchyma to be nourished. Such a disproportion may be caused either by a diminution of the nutriens, or by an increase of the nutriendum. If a minute vessel in the brain is plugged, the circulation in the area which it supplies is not wholly suspended, owing to the manifold anastomoses with neighbouring vessels ; nevertheless, a very considerable retardation of the current takes place, which may even give rise to temporary stasis and to haemorrhage, and this suffices to disturb nutrition, and so to cause fatty metamorphosis.”3
On the Histology of Hydra Fusca1
Authors: Parker T. Jeffery
Published: April 2021

The few observations I have to offer on this much-discussed subject are partly confirmatory of, partly supplementary to, those of Kleinenberg 2 they present a certain agreement with those of F. E. Schulze 3 while they are, in great measure, distinctly contradictory of the later researches of Korotneff.4
The Orthonectida, a New Class of the Phylum of the Worms1
Authors: Giard Alfred
Published: April 2021

In 1868, in an interesting memoir2 on the marine Planarians of St. Malo, Keferstein figures an animal which he designates by the name “problematic parasite.” The explanation of the plate (plate ii, fig. 8) indicates that this parasite has been found several times, and often in great quantity, in the digestive tube of the Tremellaria (Leptoplana tremellaris). The text gives us no information as to this curious organism, and it is chiefly by means of the rather rough figure of the second plate of Kerferstein’s work that we are led to refer it to the group which we are about to study.
Hubrecht’s Researches on the Nervous System of Nemertines1
Authors: Hubrecht H. W.
Published: April 2021

The above cited paper, which has just been published by the Amsterdam Academy of Sciences, and from which we have copied figures 1 to 12 on Plate XXIII, gives a detailed account of the situation and the structure of the central nervous system in the Nemerteans. After all that has been said on this subject in the works and treatises of McIntosh, Quatrefages, Keferstein, and in a former paper of the same author, it would seem superfluous once more to go over the same ground. Only it should be here remembered that the histological structure was not, or very insufficiently, considered by those authors, whereas, in the present paper, due space is allowed to the description of the histological details. The minute structure of the so-called “ sideorgans” (McIntosh’s cephalic sacs) is here also for the first time minutely entered into.
The Eye of Pecten
Authors: Hickson Sydney J.
Published: April 2021

The general absence of organs of vision amongst the members of the class Lamellibranchiata meets with a curious and interesting exception in the genera Pecten and Spon- dylus.
Terminology of Reproductive Organs and Classification of Thallophytes
Authors: Bennet Alfred W. , Murray George
Published: April 2021

Our readers are requested to substitute the following table for the one given on pp. 419, 420 of the last number of the “Journal.”
Notes on Echinoderm Morphology, No. V. On the Homologies of the Apical System, with some Remarks upon the Blood-Vessels
Authors: Carpenter P. Herbert
Published: April 2021

During the last two years the morphology of the Echinoderms has engaged the attention of several continental naturalists. Some of their observations tend to support views which I have advanced in the pages of this Journal, while others are directly opposed to them. Under the latter head come the researches of the French school into the anatomical relations of the vascular system; and it is curious that the conclusions to which Messrs. Jourdain, Koehler, Apostolides, Perrier, and Poirier have been led differ in toto from those of the German school as represented by Greeff, Hoffmann, Lange, Simroth, Teuscher, and especially by Ludwig. These last have been sufficiently described in a previous number of this Journal (vol. xxi). It is hardly time as yet to give a résumé of the observations of the French school, but one or two of their principal conclusions may be briefly alluded to.
On Plasmolysis and its bearing upon the Relations between Cell Wall and Protoplasm
Authors: Bower F. O.
Published: April 2021

It is not surprising that, after devoting their efforts for so long to the study of the nucleus, botanists should again turn their attention to the cell wall and its relation to the protoplasm. It was only to be expected that by the application of those accurate methods of study, elaborated during investigations of the nucleus, to the formation and origin of the cell wall, new results would be obtained. Such expectation has been amply justified by the works of Dippel, Schmitz, and Strasburger. The mode of increase of substance of cell walls by apposition, and more especially the mode of formation of walls in the first instance in cell division by the lateral coalescence of “microsomata,” leads naturally to the supposition that if there be such a genetic connection between the cell wall and the protoplasmic body, it would also be possible to demonstrate that the physical connection between them is very close. Further, the idea that cells may be connected with one another by delicate threads of protoplasm, which keep up a protoplasmic continuity through their cell walls, also presents itself as a natural corollary on these observations.2 Such continuity has actually been observed by Tangl1 in the endosperm of certain seeds, and by Gardiner2 in the pitted cells of the pulvinus of Mimosa, Robinia, and Amicia. Again, Fromman3 states that he has been able to observe, in various cases, a continuous network extending from the protoplasm into the cell wall.
On the Ancestral Form of the Chordata
Authors: Hubrecht A. A. W.
Published: April 2021

An all important question was raised in biology when the Law of Development came to be recognised as the only true explanation of the facts as they lie before us. This was the question: “From what invertebrate stock are the Vertebrata evolved, and which amongst the Invertebrates at present living approaches most closely in its organisation to this primitive parent stock.”In 1868 the solution appeared to have been found when Kowalevsky’s splendid researches concerning the development both of Amphioxus and of the Ascidians could be compared side by side. The Tunicate larva was for the time being proclaimed to be the missing link, to be of all Invertebrates the closest approach to the much-looked-for parent form.
The Development of the Mole (Talpa Europea. The Formation of the Germinal Layers, and Early Development of the Medullary Groove and Notochord
Authors: Heape Walter
Published: April 2021

In the following paper I propose to commence with a description of the fully-segmented ovum, leaving the details of the segmentation for a future communication; thence to trace the growth of the blastodermic vesicle and the ultimate formation of the hypoblast, epiblast, and mesoblast of the embryo; to follow the early stages of the development of the medullary canal and notochord; and finally to touch upon the phenomenon of the inversion of the layers in certain mammals, and to endeavour to show that in the mole there exists in development an intermediate condition between the inverted type, of which the guinea-pig is an example, and the normal type as exemplified by the rabbit.
The Termination of Nerves in the Liver
Authors: Macallum A. B.
Published: April 2021

After the completion of my studies on the termination of nerves in the cutaneous epithelium of the tadpole, I began investigations on the distribution and arrangement of nerves in other organs, and have now arrived at what I consider important results, more especially in the case of liver. That of man was first employed at the outset of the investigation, but I soon perceived that on account of the small size of the cells here I would have to resort to some other Vertebrate for control purposes j not that the liver of man does not yield definite results, but that these might always be open to doubt if taken alone. Fortunately at that time there were a number of Necturi in the Laboratory Aquarium, and to these I resorted, on the advice of Professor Wright, obtaining from them my most valuable preparations of the liver. The hepatic cells in these are from two to four times in diameter those in man. It is obvious, therefore, that for ascertaining the relations of nerves to the hepatic cells the liver of Necturus (=Menobranchus) is the most favorable that can be at the disposal of any histologist.
Experiments on the Formation of Infusoria in Boiled Solutions of Organic Matter, enclosed in hermetically sealed vessels, and supplied with pure air
Authors: Wyman Jeffries
Published: April 2021

Pasteur in his admirable researches on fermentation has brought forward experimental evidence to show that this process depends upon the presence of minute organisms in the fermenting fluid, and that the source of all such organisms is the atmosphere. In support of this opinion he asserts, that when a fluid containing organic matter in solution is put into a flask and “boiled two or three minutes,” and supplied only with air which has been filtered by passing through a tube heated to redness, and the flask is then hermetically sealed, no fermentation takes place, no organisms are formed, and that the contents remain indefinitely without change. But if the same solution is exposed to the air in its ordinary condition it becomes filled with various living forms. Out of a large number of experiments prepared in the manner above described, he has not known one to give a different result from that mentioned.* He further states that if the neck of the flask is drawn out into a very slender curved tube of several inches in length, the contents boiled, and then allowed to cool without the end of the tube being closed, so that the air enters at the ordinary temperature, and has free access to the interior of the flask, even then no fermentation takes place, and no organisms appear. His explanation of this is, that the air which enters first, meets with the hot steam, and the spores or organisms contained in it are killed, while those which enter the tube later move more slowly, and are deposited on the moist walls of it, without entering the body of the flask. †
On the Origin of Vertebrates from Arachnids.
Authors: Patten William
Published: April 2021

“In the growth of each science, not only is correct observation needful for the formation of true theory, but true theory is needful as a preliminary to correct observation.”—H. SPENCER.
The Development of Lepidosiren paradoxa
Authors: Kerr J. Graham
Published: April 2021

In the following pages I give an account of the chief results obtained from my investigation of the development of Lepidosiren, in so far as they relate to the skin and certain organs associated with it. Some structures which ought logically to be described now have been deliberately omitted: such are the external gills, which I propose to consider at the same time as the branchial clefts. I also make no attempt to describe the various organs with an equal degree of fulness. In regard to some, which I have found specially interesting, I give a fairly detailed account; in regard to others I am content to outline the main features.
Some Observations on the Anatomy and Affinities of the Trochidæ
Authors: Randles W. B.
Published: April 2021

The results embodied in this paper are the outcome of a series of observations on the anatomy of various species of Trochos. It was my original intention, acting on the suggestion of the late Martin F. Woodward, to confine my attention mainly to one species, viz. Trochus magus, and study that as a type form. I was unaware at that time of the existence of a memoir on Trochus, published in the ‘Zoologie Descriptive’ (38), in which a very adequate account of the anatomy of Trochus turbinatus (Born) is given by A. Robert. As this article gives a sufficiently detailed account of the anatomy of a fairly typical form, it will be unnecessary for me to give more than a general résumé of the main points of the anatomy, but rather to amplify any features that have not been fully described, and to point out any differences that may exist in the organisation of the various species which I have been able to examine, noting whether these differences are sufficient to justify the existence of the numerous sub-genera into which the genus Trochus has been divided upon conchological grounds.
Notes on the Segmentation and Phylogeny of the Arthropoda, with an Account of the Maxillæ in Polyxenus lagurus
Authors: Carpenter George H.
Published: April 2021

In the introductory note appended to his article on “The Structure and Classification of the Arthropoda” (19), Prof. E. Ray Lankester mentions “two authors who, while recently writing general essays” on the same subject, unfortunately overlooked his article, with its companion article on the Arachnida (20), as originally published in the ‘Encyclopaedia Britannica.’ These authors are the late Professor A. S. Packard, whose paper (24) was read before the American Philosophical Society in April, 1903, and the present writer, whose essay (3) was communicated to the Royal Irish Academy in the succeeding month. It is a pleasure to respond to Prof. Lankester’s courteous invitation to discuss further in this JOURNAL the questions raised, in the light of his latest invaluable contributions which, as he hopes, will now surely “not fail to come under the notice of zoologists.”
Researches on the Origin and Development of the Epiblastic Trabeculæ and the Pial Sheath of the Optic Nerve of the Frog, with illustrations of Variations met with in other Vertebrates, and some Observations on the Lymphatics of the Optic Nerve
Authors: Oration J. T.
Published: April 2021

Just over a year ago I began to feel dissatisfied with Assheton’s (1) conclusion that the cells of the optic stalk do nothing more than serve as a conductor, for the fibres of the optic nerve.
Parorchis acanthus, the Type of a new Genus of Trematodes
Authors: Nicoll William
Published: April 2021

The form with which I am about to deal is one possessing several distinctive features of importance, and for that reason I have thought it worthy of special consideration. The following account is by no means exhaustive, but it is sufficient to place the species beyond any doubt of recognition, and to establish its claim to be regarded as the type of the genus to which it belongs.
The Chætognatha, or Primitive Mollusca
Authors: T. Günther R.
Published: April 2021

It is the purpose of the present paper to demonstrate that, so far as our present knowledge of the Chætognatha goes, more numerous and more cogent reasons can be given for allying them with the Mollusca than with any other group. We shall endeavour to show that no organ of importance has been described in Chætognath anatomy which is not closely paralleled by similar and, we believe, homologous organs among the Mollusca. Indeed, we believe we can go further and demonstrate that the divergences of structure between the Chætognatha and the Mollusca are slighter than those known to exist between different orders belonging to the latter phylum. The theory of the Molluscan and Chætognath affinity explains in a simple manner many facts in the anatomy and developmental history of both groups, while there are no well-established facts which are inconsistent with it.
Materials for a Monograph of the Ascons. II.—The Formation of Spicules in the Genus Leucosolenia, with some Notes on the Histology of the Sponges
Authors: Minchin E. A.
Published: April 2021

In former memoirs (1896, 1898, 1905 [1]) I have proposed to divide the Ascons, or Calcarea Homocœla, into two families, Clathrinid æ and Leucosoleniidæ, differing from one another in all those characters which, in my opinion, are of fundamental importance for the classification of Cal. careous Sponges. I believe that the two families in question represent the most deeply-rooted phylogenetic divergence in the Calcarea Homoccela, and are two natural systematic groups, one of which—namely, the Leucosoleniidæ — approaches far nearer to the ordinary Heterocœla, such as Sycon, Grantia, Leucandra, etc., than does the other. The genus Leucosolenia, Bowerbank, in the sense in which the name is employed by me (1905 [2]), constitutes the principal, if not the only, genus in the family Leuco-soleniidæ, while the genus Clatlirina occupies a similar position in the Clathrinidæ.
A few Observations on the Encystation of Actinosphærium eichhorni under different conditions of Temperature
Authors: Mackinnon Doris L.
Published: April 2021

Previous to Richard Hertwig’s exact study “Uber Kernteilung, Richtungs-Körperbildung und Befruchtung von Actinosphaerium eichhorni” (1898), our knowledge of the life-cycle in this heliozoon Was still very incomplete, Hertwig’s work laid clear for the first time the complicated series of changes that take place within the Actinosphaerium cyst, and his subsequent work, Über Physiologiche Degeneration Bei Actinosphaerium eichhorni” (1904), threw further light on the conditions affecting the life-processes in this organism, both free-swimming and encysted.
The Yellow-Brown Cells of Convoluta paradoxa
Authors: Keeblc Frederick
Published: April 2021

Convoluta paradoxa (= C. convoluta, Auct.) is a small brown acoelous Turbellarian which lives among the seaweeds of the shore. The characteristic colour of the animal is due partly to orauge-red glands occurring in the superficial tissues, but chiefly to numerous yellow-brown cells, which are distributed fairly regularly in the sub-epidermal and deeper tissues of the body.
On the Diplochorda
Authors: Masterinan A. T.
Published: April 2021

During the summer of 1905 I paid a visit to the Biological Station at Heligoland with the object of obtaining materials for a renewed study of the development of Phoronis. I was at the same time enabled to examine living larvae of Echinoderms and a few Tornaria.
Observations on the Amœbæ in the Intestines of Persons Suffering from Goitre in Gilgit
Authors: McCarrison Robert
Published: April 2021

My researches on the ætiology of endemic goitre have led me to the conclusion that in all probability the organism which is responsible for the production of this disease is to be found in the intestinal tract. It is necessary, therefore, to give some account of the Protozoa which are so frequently present in this situation. This paper deals only with the organisms of the Amœba group, and simply gives a brief description and figures of the amœbæ found. It does not claim to be a complete account of their life-histories. While no definite statement can be made as to the pathogenicity of these amœbæ, their possible importance is obvious when it is remembered that goitre is due to an organism carried by water.
The Development of the Parasite of Oriental Sore in Cultures
Authors: Row R.
Published: April 2021

[The following memoir is made up from two communications, dated respectively December, 1908, and January, 1909, which I received from Dr. Row. Each letter was accompanied by sketches and stained preparations; from the latter the figures on Pl. 20 have been drawn by my assistant, Miss Rhodes, at the Lister Institute. The account given here is, for the most part, in Dr. Row’s own words; any remarks of mine are in square brackets.
The Development of the Temnocephaleæ
Authors: Haswell Professor W. A.
Published: April 2021

Though several additions of importance 1 have been made to the literature concerned with Temnocephala and its allies since 1893, when I published an account of the group under the title “A Monograph of the Temnocephaleæ” (8), no attempt has been made hitherto to deal with the embryology of any of its members. In view of the interest which attaches to them on account of their isolated character and problematical relationships with other sections of Platodes, it is very desirable that something should be done towards filling this hiatus in our knowledge.
On the Bionomics and Post-Embryonic Development of certain Cynipid Hyperparasites of Aphides.
Authors: D. Haviland Maud
Published: April 2021

Bothryoxysta curvata, Kieff., Charips victrix, Hartig, and Alloxysta erythrothorax, Westw., are hyperparasites of aphides through Aphidius (Braconidae). Reproduction may be either sexual or parthenogenetic. The egg is laid in the haemocoele of the host larva before the death of the aphid, and post-embryonic development is internal. A trophic membrane of hypertrophied cells is formed round the embryo. The larva is, at first, hypermetamorphic ; and exhibits greater development of the chitinous cuticle than is usual in endoparasites ; but in the succeeding stages it approximates more closely to the general hymenopterous type. G. The development of the Aphidius is arrested at a certain point, and metamorphosis does not take place. The Cynipid, when ready to pupate, makes its way out of the Aphidius, whose remains it devours, and undergoes metamorphosis within the cocoon previously woven by the latter in the skin of the aphid. These forms differ in certain particulars from the ento-mophagous Cynipidae previously described, and the chief differences are discussed. Comparison is also made of the larvae of other Hymenoptera Parasitica, particularly of Perilampus. Certain problems of metabolism are pointed out, and it is suggested that respiration may be partly rectal. These Cynipidae are economically injurious as they check the Aphidius in its destruction of plant-lice; but there is high mortality among the larvae owing to secondary parasitization of the Braconid by other hyperparasitos.
Notes on the Larval Skeleton of Spatangus purpureus.
Authors: Ohshima Hiroshi
Published: April 2021

Although ‘one of the very first Echinoderms of which artificial fertilization and rearing of the larvae were undertaken’ (Mortensen, 6, p. 14), the development and especially the structure of the larval skeleton of Spatangus purpureus have been rather imperfectly known. Krohn’s descriptions and figures (2, 3) are not quite satisfactory with regard to the skeletal structure, and, moreover, the larvae described in his second paper are doubtful as to their specific identification (Mortensen, 6, p. 15). Through Mortens on’s renewed observations on the artificially-reared larvae of this species (6, pp. 14-17) the external features of the larval development are now made clearer. As to the larval skeleton, however, he was only able to give some brief information owing to the unfortunately bad state of preservation of his specimens. Among other Spatangoids, Echino - cardium cordatum and Brissopsis lyrifera were carefully studied by Maebride (4) and Mortensen (7, pp. 144-8), and the larvae of these three species have been shown to have such a striking resemblance to each other in early stages that it is desirable to ascertain some more minute diagnostic characters for each species. In such circumstances it seems not unnecessary to put on record detailed descriptions of the skeletal structure of the larva of Spatangas purpureus.
The Behaviour of the Golgi bodies during nuclear division, with special reference to Amitosis in Dytiscus marginalis.
Authors: Ludford Reginald James
Published: April 2021

Dictyokinesis, or division of the Golgi bodies during cell division, has recently been worked out by Professor J. Bronte Gatenby and the present writer in the male germ-cells of several animals (5). It was found that the distribution of the Golgi elements, or dictyosomes, to both halves of a dividing cell was a very haphazard process and was unaccompanied by any splitting of the dictyosomes such as occurs in the case of the chromosomes. In the cricket Stenobothrus, the dictyosomes become scattered in the cytoplasm of the spermatogonium before cell division takes place, and they remain in this condition during meiosis, so that approximately a half become contained within each of the newly-formed cells. A different process, however, occurs in the Mammals, Mus and Cavia, and in the Molluscs, Helix and Limnaea. The Golgi bodies in the spermatogonia of these types consist of a number of dictyosomes arranged around the archoplasm, inside which is the centrosome. As this latter organ divides, preparatory to the formation of the spindle, its two constituent parts separate and carry with them to both ends of the cell, approximately half of the archoplasm, still with the dictyosomes attached. During late prophase, the dictyosomes become temporarily detached from the archoplasm and scattered throughout the cell, and then at the late telophase they collect together again around the archoplasm.
Further observations on Chromosomes and Sexdetermination in Abraxas grossulariata
Authors: Doncaster L.
Published: April 2021

The following paper was left by the late Professor Doncaster in an incompleted condition, and, as I was one of his assistants during his last year ‘s work, it has been entrusted to me to prepare for publication.
Histology of the Soft Parts of Astraeid Corals.
Authors: Matthai G.
Published: April 2021

The following account of the histology of the soft parts of the Astraeidae is supplementary to the description given in the Introduction to my paper on ‘A Revision of the Recent Colonial Astraeidae possessing Distinct Corallites’ (25, pp. 1-32). It is based on the study of a large number of polyps belonging to various Astraeid species of the Indo-Pacific and Atlantic regions, particularly of Fa via fa vus (Forsk.), Fa via hululensis (Gard.), Coeloria daedalea (Ell. and Sol.), Leptoria gracilis (Dana), Eus mili a as per a (Dana). During a short stay at the Carnegie Marine Biological Station at Tortugas (July 16-August 2, 1915), living colonies of all coral species of that locality were kept under observation, but at that time larvae were extruded only from colonies of F avia f r a g u m (Esp.). These were fixed at different intervals during the free-swimming stage—from eight hours to about ten days—in Flemming’s fluid, corrosive acetic solution, and Bouin’s fluid, and were subsequently sectioned serially to thicknesses of 4 μ, 6 μ, 8 μ, and 10 μ in order to compare their histology with that of adult colonies. No larvae of any species were obtained during a subsequent visit to the Bermudas (Aug. 20 - Sept. 14). Solid embryos lying in the coelenteric cavities of polyps from a colony of F a via fragum, which Dr. Vaughan forwarded to Professor Gardiner from South Bight, Bahamas, and which have been sectioned, were also studied.
The Yolk-Sac and Allantoic Placenta in Perameles.1
Authors: Flynn T. Thomson
Published: April 2021

It is proposed in the present communication to initiate the publication of a series of papers dealing with marsupial embryology. The facts and interpretations embodied will be based on result of an investigation into an amount of marsupial material now collected in the Biological Laboratory of the University of Tasmania and fairly representative of the Tasmanian fauna.
Nuclear Divisions in Amoeba proteus.
Authors: Taylor Monica
Published: April 2021

No definite answer, so far as I have been able to ascertain, has yet been given to the question that is inevitably provoked by the spectacular rapidity with which amoebae increase in number in laboratory cultures, viz. ‘How does the nucleus divide ?’ In attempting to answer this question it is important to remember, a fact which five years’ experience in cultivating amoebae on a large scale has taught, that the most luxuriant cultures are subject to periods of depression. Unless the necessary precautions be taken (5) they die down and remain dormant for a varying period of time, then gradually recover.
The Transition of Peritoneal Epithelial Cells into Germ-Cells in Gallus Bankiva
Authors: Gatenby J. Brontë
Published: April 2021

In a fowl (Gallus bankiva) which possessed some male characters (comb, wattles, and male pugnacity) the ovary contained an adenoma and was atrophic. Within this effete ovary the peritoneal epithelium had begun to elaborate new testicular tissue. Certain regions outside the gonad contained metamorphosing peritoneal epithelial cells. The transition of avian peritoneal cells into germ-cells takes place in a manner similar to what has already been described in Amphibia (Gatenby). The basophil peritoneal epithelial cell, at first clear, becomes granular. Its nucleus becomes spherical and a pure nucleolus appears: the cytoplasmic granules pass from basophility to oxyphility. At this period the cells divide and the oxyphil granules gradually dissolve into a smooth oxyphil ground cytoplasm. The cells, after division, are found to be arranged in columnar manner as spermatic tubules. In each tubule a lumen appears at a later period. Attention has been drawn to the work of Dr. Crew and Miss Fell, who have already described the metamorphosis of peritoneal cells into germ-cells.
On the Occurrence of the ‘Enteronephric’ Type of Nephridial System in Earthworms of the Genus Lampito
Authors: Bahl Karm Narayan
Published: April 2021

The ‘enteronephric’ type of nephridial system previously discovered by the author in the genus Pheretima has now been shown to be present in the genus Lampito also. The present investigation extends the distribution of this new type of excretory system and makes it probable that it occurs in other genera as well. In essential the nephridial system of Lampito agrees with that of Pheretima previously described; but while in Pheretima the ‘enteronephric’ nephridia are minute and multiple and have been described as micronephridia, these nephridia in Lampito are large and paired in each segment and are described as meganephridia. There are three distinct kinds of nephridia in Lampito, namely the septal, the pharyngeal, and the integumentary; of these, the septal ones communicate with the lumen of the gut through an elaborate system of ducts, the pharyngeal tufts of nephridia open into the pharyngeal cavity through bundles of ductules, while the integumentarios open on the skin individually through separate nephridiopores. The septal nephridia of Lampito resembles those of Lumbricus in their shape and disposition, but in their place of opening they agree with the enteronephridia of Pheretima. Therefore both micronephridia (Pheretima) and meganephridia (Lampito) can be ‘enteronephric’. Since there is no anatomical difference between micro- and meganephridia but only a difference in size, this classification of nephridia should be abolished. A better system is to classify them according to their place of opening and recognize ‘exonephric’ and ‘enteronephric’ types of nephridia, and amongst each of these types to distinguish between those that have an open internal funnel and those in which the internal end is closed. The septal nephridia of Lampito are characterized by the presence of multiple funnels to a single nephridium, and since in some species all the funnels are functional and in others one is functional and the others vestigial, it is suggested that the branching of funnels is a stage leading later to the multiple nephridia of Pheretima. Close similarity in their nephridial and other systems suggests a genetic relationship between the two genera Lampito and Pheretima, and the suggestion is supported by facts of geographical distribution of the two genera. Lampito provides a connecting link between Megascolex and Pheretima.
The Cytological changes observable in irradiated Bean Root Tips
Authors: Patten Ruth E. P. , Wigoder Sylvia B.
Published: April 2021

The effect of X-rays is divisible into two periods, one showing the immediate effect, the second period being one of recovery. The immediate effect includes gradual cessation of mitosis, and the production of abnormalities in those cells which were in the process of division or were about to divide at the time of irradiation. The length of time during which no cells enter into mitosis depends on the size of the dose. During the recovery period some cells again enter into mitosis but their division is usually of an abnormal type. Irradiation acts on cells in the interphase by interfering with some physiological process. These cells are then unable to enter into mitosis until the effect of irradiation has passed off.
On a new Hermaphrodite Syllid
Authors: Goodrich E. S.
Published: April 2021

The worm described in this paper was found by me in material collected by the fishermen of the Zoological Station at Naples from the sandy bottom near the western shore of the bay of Naples. Although small it is fairly conspicuous, being milky white in colour and active in its movements. It belongs to the genus Pionosyllis, and like most of its near relatives bears its young attached in pairs on the segments of the middle region of its body, as admirably described and figured by Pierantoni (5). The breeding season begins in May, and the specimens I collected during my visit to Naples last April were not fully mature. To Mr. J. Z. Young, however, I am indebted for mature and embryo-bearing specimens collected in June.
On the skeleton of the hyoid arch in Rays and Skates
Authors: Beer G. R. de
Published: April 2021

The relations to the afferent pseudobranchial artery of the lower ray-bearing part of the hyoid arch skeleton in Rays show that the latter is not the ceratohyal, but a pseudohyoid. Investigation of the development of Torpedo shows that the pseudohyoid arises distinct from the hyoid bar, and that the ceratohyal is much reduced. The ceratohyal in Rhynchobatus is not so much reduced as in Torpedo, Pristis, or Raja, and it still bears a small number of hyal rays. The pseudohyoid is formed as the result of fusion of hyal rays, and pseudohyoid bars are present more or less well developed in a large number of Sharks. The enlargement of the pseudohyoid and reduction of the ceratohyal in Rays is associated with the increased distance between the mouth and the first gill-slit, and the necessity for providing a support for the hyal rays and the anterior wall of the first gill-slit. Similar factors have been operative in the Dipnoi and have led to analogous results.
The Nephridia of Asymmetron and Branchiostoma Compared
Authors: Goodrich Edwin S.
Published: April 2021

The excretory organs of Branchiostoma (= Amphioxus) are so peculiar, in that they resemble the protonephridia of many invertebrates and differ radically from the excretory tubules of other vertebrates (Goodrich, 1902 and 1909), that it is a matter of some importance to ascertain whether organs of similar structure occur in the allied genus Asymmetron. Andrews, so far as I am aware the only author who has dealt with this genus in detail, failed to find them in the Asymmetron lucayanum he described (Andrews, 1893, p. 229). During a recent visit to Bermuda I obtained specimens of this species,1 and give here the results of the study of fresh and preserved material carried out in the Bermuda Biological Station during last July and August and since in Oxford. A comparison is also made with the excretory organs of Amphioxus.
The Male Meiotic Phase in Five Species of Marsupials
Authors: Drummond F.H.
Published: April 2021

This paper deals with the spermatogenesis of five species of marsupials including representatives of three families. The two species of Bettongia of the family Macropodidae have been studied in most detail. In the other forms little more has been done than to establish the number of chromosomes and the type of sex chromosomes.
On the Teeth of the Larval Belone vulgaris, and the Attachment of Teeth in Fishes
Authors: Moy-Thomas J. A.
Published: April 2021

The upper jaw teeth of the larval Belone pierce the epidermis as solid structures, unattached to the bone and afterwards become attached by the growth of their bases directly to the premaxilla. These teeth are very similar in structure to those of the larval Eel. A curious feature is shown in their development, the original dentine cone becoming clear apparently to form enamel-like substance. The lower jaw and pharyngeal teeth of the larval Belone develop as hollow cones of dentine, and become attached to the bone either directly or by means of separate ‘intermediate ‘pediments of bone. All the teeth of Salmo, Amia, Acipenser, and Polypterus are attached to the bone directly or to upgrowths more or less continuous with the bones. The bony ‘intermediate’ plates of the Dipnoi fuse to form the adult tooth-plate, the actual denticles disappearing. The supporting pediments are shown to be only bony supports developed precociously in connexion with the teeth, and may be formed directly from the bone or separately as ‘intermediate’ pediments, and are in no way different from the remainder of the bone. The embryology of teeth and bone in fishes suggests that they are distinct structures, and that their close association in ontogeny and phylogeny is due to the necessity of acquiring a firm base, and not because they are parts of the same structure.
On the Significance of the Enteronephric Nephridial System found in Indian Earthworms: I. Evidence from their Habits and Castings
Authors: Bahl Karm Narayan
Published: April 2021

In 1919 (1) I described in the pages of this journal a new type of nephridial system found in Indian earthworms of the genus Pheretima. The nephridia in this system are remarkable in that they discharge their excretion into the intestine instead of on to the surface of the body. The excretion is conveyed through a system of ducts, of which the most important are a pair of longitudinal excretory ducts lying above the intestine, one on each side of the mid-dorsal line; these ducts open into the intestine all along its length through segmentally arranged apertures. I gave the name ‘enteronephric’ to this new type of nephridial system to distinguish it from the ‘exonephric’ type found in Lumbricus, and put forward the suggestion, originally made to me by Dr. W. N. F. Woodland, that ‘the discharge of excretory fluid into the intestine may be a special adaptation for the conservation of moisture in a dry climate’. It was assumed that the water-content of the excretory fluid discharged into the gut was reabsorbed by the intestinal epithelium for the needs of the organism, while the solid excretory matters passed out of the body through the anus. Later, in 1924 (2), I found a similar ‘enteronephric’ system in another genus of Indian earthworms, Lampito (Megascolex), in which the nephridia are large and paired—meganephridia—like those of Lumbricus as contrasted with the numerous small micronephridia of Pheretima; but in the manner of their opening into the intestine through a pair of longitudinal excretory ducts and segmentally arranged apertures, these nephridia of Lampito agree with those of Pheretima. Still later in 1926 (3), I found that a third genus of earthworms called Woodwardiella also possessed an ‘enteronephric’ system very similar to what I had previously described in Pheretima and Lampito. I concluded, therefore, that this enteronephric type of nephridial system was widely prevalent amongst earthworms—particularly in the family Megascolecinae to which all the three genera possessing this type of nephridial system belong.
The Formation of the Hen’s Egg V. Histochemistry of Yolk-Formation Proteins1
Authors: Marza V. D.
Published: April 2021

The best known protein in the yolk of the hen’s egg is vitellin. Next to that one finds livetin, Gross’s protein,1 and the nucleoproteins. According to Hugounencq and Morel there is 1μ40 gr. of vitellin in the hen’s egg. Livetin is in lesser quantity. The quantity of nucleoproteins does not go beyond 2 mgr.