bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Molluscs of the Great African Lakes. IV. Nassopsis and Bythoceras
Authors: Moore J. E. S. 
Published: April 2021

ABSTRACT
Among the numerous forms of molluscs that appear to be peculiar to Lake Tanganyika at the present time, there are three very marked genera—Paramelania, Nassopsis, and Bythoceras, which, owing to the substantial similarity existing between their shells, might, and have hitherto been regarded as closely associated forms. The first of these to be discovered, Nassopsis, was originally classed by S. P. Woodward1 among the Melanias, and as a member of the sub-genus Melanella, his determination being made from some emptyshells which had been brought from Tanganyika by Captain Speke, during Burton’s celebrated journey to that lake. The second genus, Paramelania, was formed by Smith,2 in 1881, to include a Somewhat similar form of empty shell which had been brought from the same locality by the missionaries; and to distinguish the members of this genus from the original Melanella nassa of Woodward, Smith3 placed the latterform in the new genus of Nassopsis.
Remarks on some Recent Work on the Protochorda, with a Condensed Account of some Fresh Observations on the Enteropneusta
Authors: Willey Arthur 
Published: April 2021

ABSTRACT
The eighth volume of the well-known ‘Traité de Zoologie Concrète,’ by Professor Yves Delage and M. Edgard Hérouard, published in 1898, is devoted to what the authors style the Procordés or Prochordata, a group which is made to include three classes, namely, Hemichordia, Cephalochordia, and Urochordia. It is a pleasure to turn to a text-book in which the Enteropneusta are treated on equal terms with the Cephalochorda and the Urochorda, especially when, as in this case, the distinguished authors have aimed at impartiality—a quality which in one or two places has led them beyond the bounds of discrimination. It goes without saying that the work is an excellent one, and admirably calculated, on the whole, to give a just idea of these animals ; but on the present occasion I am neither concerned with its many excellences nor with its few blemishes, but merely with the subject matter.
Note on Intra-uterine Eggs of Heterodontus (Cestracion) Phillipi
Authors: Haswell W. A. 
Published: April 2021

ABSTRACT
In 1901 Bashford Dean published in the ‘Aunotationes Zoologicæ Japonenses’ a paper, entitled “Reminiscence of Holoblastic Cleavage in the Egg of the Shark, Heterodontus (Cestracion) japonicus Macleay,” in which he described on the surface of the egg of that fish a system of lines (furrows) supposed by him to be indications or “reminiscences” of complete segmentation. In a postscript, he adds :
The Pecten of Gallus domesticus
Authors: Mann Ida C. 
Published: April 2021

ABSTRACT
That curiously puzzling and beautiful structure, the pecten of the bird’s eye, has long been a subject of investigation from various points of view. Some observers have been fascinated by its histological appearance, others have by experiment, analogy, and hypothesis endeavoured to assign it a suitable function, while others have found in its development a solution of its mysteries. It has been studied at intervals since about 1870, and it still presents problems which are obscure.
The Development of the Skull in the Sole and the Plaice
Authors: Berrill N. J. 
Published: April 2021

ABSTRACT
Various stages of Solea variegata were obtained and the development of the chondrocranium was determined. A less complete series of Pleuronectes platessa formed a sufficient basis for comparison. The material had been tixed in formalin, and sections were stained in thionin blue, victoria blue, haematoxylin and eosin, and Mallory’s triple stain, the last being the most satisfactory for cartilage, while haematoxylin was better for general structure.
The Chromosomes of Four Species of Marsupials
Authors: Altmann Stella C. A. , Ellery Mavis E. W. 
Published: April 2021

ABSTRACT
This is a joint paper only in so far as the results of the two authors are combined. The first author is solely responsible for the first three species dealt with, and the second author for Potorous tridactylus. This work was carried out in the Zoological Laboratory of the University of Melbourne, the former author working under the terms of the Fred Knight Research Scholarship, and the latter under the Howitt Scholarship.
Variations in the Form of the Golgi bodies during the Development of Neurones
Authors: Rau A. Subba , Ludford R. J. 
Published: April 2021

ABSTRACTIn the spinal ganglia of the chick of four days the Golgi apparatus or body is in the form of a cluster of granules or rodlets, grouped around the centrosphere, at one side of the nucleus (fig. 1, Pl. 39). In a seven-day chick the Golgi body has increased in size and has begun to spread farther around the nucleus (fig. 3, Pl. 39). All ganglion cells examined, both those of the spinal cord and of ganglia, have the Golgi apparatus in this compacted form during their early stage. At a certain period which varies in the different cells the apparatus spreads out in the cytoplasm (fig. 4, Pl. 39), so that in the adult ganglia the apparatus is more or less scattered throughout the cell (figs. 5, 6, and 7, Pl. 39). It is uncertain to what extent variations in the form of the apparatus, whether reticulate or in the form of individual rodlets, are due to differences in the degree of impregnation with the silver. The plane of the section is also an important factor in determining the appearance presented by the apparatus. The medullary cells of the suprarenal body, which are derived from the central nervous system, have the apparatus in the form of a coiled network or cluster of granules at one pole of the nucleus, similar to the cells of the spinal ganglia at the early stage of development. It is suggested that the scattered form of the Golgi apparatus in adult ganglion cells is an expression of the high degree of metabolism existing in these cells.
The Early Development of Astropecten irregularis, with Remarks on Duplicity in Echinoderm Larvae
Authors: Newth H. G. 
Published: April 2021

ABSTRACTI. (1) The normal development of Astropecten irregularis is described up to the twenty-fifth day.(2) About a third of the larvae possessed two pore-canals, and larval twinning was observed in two cases.II. There is insufficient evidence for believing that normal Echinoderm larvae possess a ‘latent’ bilateral symmetry.III. The following provisional conclusions are reached regarding duplicity in Echinoderm larvae:(1) The various kinds of duplicity form a series.(2) They are of the same nature as those found in vertebrate embryos, and are probably due to similar causes.(3) They may be determined by(a) Alteration of the polarity of the egg;(5) Interference with processes of early development affecting gastrulation;(c) Physiological inhibition or mechanical deformation of the tip of the archenteron.(4) Their ultimate facies, in the case of (c), is determined largely by excess or defect of nutrition.
Xenopleura vivipara, g. et sp.n. (Enteropneusta)
Authors: Gilchrist J. D. F. 
Published: April 2021

ABSTRACT
Some four years ago, while examining a rocky part of the coast of False Bay at very low tide, I found a small Banaglossus different from the species (Ptychodera capensis), which is not uncommon near the locality. The difference was most obvious in the absence of the conspicuous genital pleurae, and the presence of a small number of rounded branchial apertures.
On the Origin of the Connective-tissue Ground-substance in the Chick Embryo
Authors: Baitsell George A. 
Published: April 2021

ABSTRACT
Szily (26) demonstrated in the early development of. the chick embryo, as well as in certain other species, a cell-free, fibrous, connective-tissue ground-substance which was quite generally present, filling the various cavities of the embryonic body. This investigator was of the opinion that this material was intracellular in its origin, arising, as he believed, by a transformation of cell processes from any of the surrounding cells, without regard to the particular germ-layer to which they belonged, but previous to the advent of the mesenchyme cells.
Histoire Naturelle des Annelés marins et d’eau douce. Annélides et Gephyriens
Authors: Quatrefages Armand De 
Published: April 2021

ABSTRACT
The worms of our seas and fresh waters—variously classified and arranged by those who have studied them—have commanded till quite recently but a very poor share of the attention of the working naturalist. The probable reasons of this circumstance are to be found in the retiring nature of these animals, and the comparative obscurity of the characters which separate them specifically and generically, as well as the difficulty of tracing their life-histories and anatomical development. We believe that we are not exaggerating the true state of the case when we say that there is not a single work extant, such as is available for other groups of animals, by which species of Annelida may be satisfactorily identified—even those occurring in such limited areas,as our own and neighbouring seas. The few systematic works which are to be had, of which the British Museum Catalogue published in 1865 may be taken as a specimen, are simply useless for the purposes of the present day, owing to insufficiency in details in both descriptions and figures. On the other hand, the work of M. Malmgren on the Annelids of the North Sea, and such descriptions of species and ample drawings as those of Kinberg* and Ehlers, † - are examples of the manner in which the Annelida should be treated ; and until we get such works from many different localities the synonymy must remain in its present shocking condition, very many species which bear the same name in France, England, Germany, and Scandinavia, being quite distinct, and those bearing different names being often identical.
On some New and Rare Diatomaceæ from the West Coast of Ireland
Authors: O’meara Rev. Eugene 
Published: April 2021

ABSTRACT
The matter supplied to me, of which only a small portion has as yet been searched, was raised in August last, as Dr. E. Perceval Wright informed me, from depths varying from ten to thirty fathoms, off the Islands of Arran, in Galway Bay. Taking into account the number and rarity of the species found in it, this gathering may be regarded as one of the most interesting ever made, certainly the most interesting ever made in Ireland.
Another Interpretation of Dr. Moxon’s Discvoery
Authors: Gedge J. 
Published: April 2021

ABSTRACT
In the number of this Journal for October, 1866, Dr. Moxon brought forward a valuable paper on the distribution of the antennal nerve in a Culex larva. The value of this paper, to my mind, however, consisted in the accurate account and delineation he gave us of what he saw. With Dr. Moxon’s observations I find no fault; but with his conclusions I cannot agree. On these latter I had hoped that some more able and better-known observer than myself would have come forward and given his opinion; but as the last number of the Journal was silent, I feel bound to show that consent to his views is not universal—that his observation may bear another interpretation.
On the Protophyta of Iceland
Authors: Lindsay W. Lauder 
Published: April 2021

ABSTRACT
When we consider the geographical position of Iceland, the extent of its traffic with Britain and Scandinavia, the abundance of the localities which it contains affording suitable habitats for such forms of vegetation, it is not a little remark-to find its Flora extremely defective in soupe of its departments, and notably so in that of the Protophyta and the lower or Chlorospermous Algœ.
The laws of the movements in microscopical plants and animals whilst under the influence of light
Authors: Cohn F. 
Published: April 2021

ABSTRACT
BY microscopical animals Professor Cohn means only the Infusoria, and especially those mouthless genera of Infusoria which are provided with cilia. Those which are provided with mouths (Stomatoda of Siebold) bear in their definite motions, which are correlated with their taking up solid nourishment, a marked differentiating character. By microscopical plants only those genera are understood which are possessed of an independent power of migration, or of a developmental condition in which this is the case. Both classes taken together are to he termed merely “microscopical organisms.”
On the Origin, Growth, and arrangement of Sponge-spicules: A study in Symbiosis
Authors: Dendy Arthur 
Published: April 2021

ABSTRACT
There are perhaps no structures met with in the animal kingdom of which the origin and significance are more difficult to explain than the spicules that form the skeleton of calcareous and siliceous sponges. The larger and usually less complex forms, technically known as megascleres, we are apt to accept as necessary constituents of the skeleton specially adapted to their position in the sponge, without stopping to reflect that there are many sponges which manage to get on very well without any spicules at all, sometimes, indeed, without skeleton of any kind. The smaller ones, or microscleres, met with amongst the siliceous sponges, are much more enigmatical, for they usually occur scattered promiscuously throughout the soft tissues, while they exhibit the most surprising variety of exquisitely symmetrical forms, the meaning of which it is impossible to interpret in terms of the physiological requirements of the sponge. At the same time these forms, as well as those of the megascleres, while exhibiting a remarkable degree of specific constancy, can be arranged in beautifully graduated series that leave little doubt in the mind of the trained observer that they owe their existence to some evolutionary process.
Studies on the Golgi Apparatus in Gland-Cells. IV. A Critique of the Topography, Structure, and Function of the Golgi Apparatus in Glandular Tissue
Authors: Bowen Robert H. 
Published: April 2021

ABSTRACT
In the first of this series of ‘Studies‘ I suggested that the conclusive demonstration of the secretory theory of the Golgi apparatus must depend upon further and more critical evidence bearing on three principal points. These are: (1) a demonstration that the general topographical relationship of Golgi apparatus and secretory granules is always such as to allow a possibility of causal connexion between them ; (2) a more intimate knowledge of the finer structural features of the Golgi apparatus in general ; and (3) a critical demonstration of the relation of an individual secretory granule to the material of the Golgi complex. In the preceding papers of this series (Bowen, 1926 a, b, and c) I have described the objective results of an extended examination of glandular tissue, particularly in their bearing on the three points just mentioned. In this paper I propose to analyse my results with the hope of arriving at some evaluation of the theory which Dr. Nassonov (1923 and 1924 a) first definitely suggested, and which I have recently (1924) tried to extend into a more general conception of the secretory function of the Golgi apparatus. My observations have been focused particularly upon the Golgi apparatus, and little or no attention has been paid to other components of the cell. This was done deliberately, in the belief that these other components had been examined with sufficient thoroughness to indicate their probable value to a general theory of secretion. In another place I shall deal more critically with these matters, but here I purposely omit everything but the briefest reference to the secretory possibilities of cellular constituents other than the Golgi apparatus. In my opinion the older theories of secretory synthesis have broken down, and the field is now clear for a thorough examination of the Golgi apparatus as a synthetic intermediary in the process of secretion. 1
The Chromosome Complex of Gammarus Chevreuxi, Sexton.: I. Spermatogenesis.
Authors: Palmer Richard 
Published: April 2021

ABSTRACT
The chromosomes of Gammarus chevreuxi are small, ovoid, and minutely heteromorphic, and have a diploid number in the male of 26, this number being arrived at by a study of spermatogonia, spermatocytes, and synapsis stages. This chromosome number includes in the male an X- and a Y-chromosome, the former being larger and the latter smaller than any of the autosomes. The spermatogonia fall into two distinct classes as regards chromosome size, the large plates being probably merely the later stages of the spermatogonial series. While Gammarus does not provide favourable material for the detailed study of synapsis, the chromosomes appear to spin out in the typical way in the early synaptic stages. Huxley’s conclusions regarding cross-over values and chromosome configuration in Gammarus are discussed in the light of these facts.
On the Tracheal System of Collembola, with special reference to that of Sminthurus viridis, Lubb
Authors: Davies W. Maldwyn 
Published: April 2021

ABSTRACT
No extensive study of the tracheal system of Collembola has previously been made. The general plan of the tracheae has been worked out on Sminthurus viridis; two independent systems exist. The presence of only a single pair of spiracles constitutes a unique condition among adult insects. The position of these is in the anterior region of the prothorax, and not in the head or cervicum as previously believed. The structure of the spiracles is extremely primitive and they possess no closing apparatus. The tracheae branch dichotomously, but no anastomosis exists between the systems of the two sides of the body. Taenidia are present, but no ‘transition cells ‘have been observed and the fine tracheae terminate in unbranched tracheoles. The initial entrance of air into the tracheae is through the spiracles ; the displacement of fluid is very slow and the. whole system is not completely filled with air until about fourteen days after emergence from the egg. Tracheae are found to be a constant feature in all members of the Sminthurinae examined. Various methods of technique adopted are given.
Observations on the Development of the Pronephros of the Sturgeon, Acipenser rubicundus
Authors: Fraser Elizabeth A. 
Published: April 2021

ABSTRACT
The following observations were made from a series of embryos and young larvae of Acipenser rubicundus, which were kindly sent by Mr. W. J. K. Harkness of the Canadian Fisheries to Professor D. M. 8. Watson at this college. I am much indebted to Professor Watson for the loan of this valuable material.
The Origin of Dust-Cells in the Lung
Authors: Carleton H. M. 
Published: April 2021

ABSTRACT
The vital injection experiments of Permar have been repeated. The transformation of endothelial cells of the lung capillaries into dust-cells, as claimed by this author, could not be established on a scale at all sufficient to account for the immense number of dust-cells. The evidence of tissue culture is discussed and is claimed to favour the idea that dust-cells are derived from the cells lining the alveoli, and that these are largely cubical epithelial cells (Binet and Champy; Carleton) and not histiocytes (Lang). That dust-cells are formed from the cubical epithelial cells is urged from the study of sections of dust-laden lungs. That the heart-failure cell has a similar derivation to the dust-cell is also urged. Stages in the formation of dust- and heart-failure cells are described and figured. The changes caused in the pulmonary alveoli by (i) poison gas, (ii) the disease 1 Jagziekte ‘, and (iii) collapse of the lung are discussed. The conclusion is formed that these changes favour the view that the cells lining the alveoli are epithelial rather than histiocytic. Some of the recent work of the Aschoff school (papers of Westhues and Seeman) is described and discussed. Policard’s theory that the final alveolar lining is histiocytic (i. e. mesodermal) is described.
Difficulties for accepting this view are given.
The Development of the Nucleus of Amoeba Proteus. Pallas (Leidy) [= Chaos Diffluens (Schaeffer)]
Authors: Taylor Monica 
Published: April 2021

ABSTRACT
A very thorough knowledge of the nuclear phenomena in an organism so largely employed as is Amoeba proteus by investigators in many branches of science, no less than by teachers of biology, is greatly to be desired. That there are, at present, gaps in this knowledge is quite evident from an inspection of the literature. One such gap was responsible for a question asked of me by Professor Grégoire while I was working in the Carnoy Institute, Louvain, in 1924. This question emphasized the fact that, in my paper on ‘Nuclear Divisions in A. proteus’, I had, as had Doflein (8) before me, left it open whether or no the portions of the karyosome which stain more deeply than the rest consist of chromatin. When reading over the manuscript of my paper Professor Graham Kerr had said that he saw no reason for their not being chromatin, while fully sympathizing with my reluctance to decide the question from observation made on the nucleus of the adult. Griiber (11) had no hesitation in describing these portions of the karyosome as ‘chromatin-containing’? While I was working out the phenomena connected with the formation of encysted young, the karyosome of the fully mature individual had appeared to me to be nothing more than a portion of the nuclear reticulum where the meshes were not quite so large as in the surrounding areas. In contradistinction to this condition was that which obtained in those young A. proteus which I had been able to examine before the publication of my paper (25, p. 137, Text-fig. 10) and of which a preliminary account was given. In these the karyosome appeared much more solid and less reticulate, being quite the most conspicuous structure in the nucleus.
A Contribution to the Embryology of Pieris rapae
Authors: Eastham L. 
Published: April 2021

ABSTRACT
Maturation of the ovum of Pieris rapae takes place immediately after oviposition. Cleavage begins within the first hour, and of the resultant nuclei those destined to form blastoderm move outwards to the cortical layer ; the remainder are left in the yolk as vitellophags. The movement outwards of the nuclei is partly attributed to a streaming of cytoplasm which drags the nuclei to the periphery. The formation of the embryonic rudiment is described, as also are its changes in form, which consist chiefly of an increase in length and decrease in width. These are accompanied by anterior and posterior flexures of the embryo into the yolk. Gastrulation is effected by a process of overgrowth of the middle plate by two lateral plates. This is preceded by differentiation of the middle plate by loss of cells from its whole length to the yolk, and by a shallow invagination developing along the median line of the ventral plate. Endoderm is formed in anterior and posterior rudiments, which develop as proliferations in the positions of future mouth and anus. Yolk-cleavage and amnion and serosa formation are described. All the processes examined in development take place from before backwards.
The Passage of the Spermatozoa into the Cocoon in the Brandling Worm (Eisenia foetida, Sav.)
Authors: Grove A. J. 
Published: April 2021

ABSTRACT
Sections through the albumen of a cocoon fixed some short time after deposition show spermatozoa in varying positions indicative of a condition of inactivity following upon failure to enter an egg. In the albumen of cocoons dissected from off the clitellum of the worm just prior to deposition, no spermatozoa could be detected. In freshly deposited cocoons spermatozoa are to be found surrounding the eggs, but not actually penetrating the vitelline membrane. The outline of the spermatozoa is sinuous, indicating that they were actively swimming at the time of killing.
It is evident, therefore, that although the eggs are passed back into the cocoon whilst the latter is still surrounding the clitellum, the spermatozoa enter during the passage of the cocoon over the apertures of the spermathecae.