bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sanguinicola From The Sudan
Authors: Woodland W. N. F. 
Published: April 2021

ABSTRACT
In 19081 the description by Dr. Marianne Plehn of Sanguinicola as the only known example of a Cestode (Cestodarian) infesting the blood aroused considerable interest, and though the subsequent conclusion by Odhner in 19112 that Sanguinicola was rather to be regarded as an extreme form of suckerless haematobic Trematode somewhat detracted from the significance of the discovery, yet on account of its plesio-Turbellarian structure and possible Turbellarian affinities, Sanguinicola still remains a zoological type of importance.
On Centropygus joseensis, a Leech from Brazil
Authors: Badham Charles 
Published: April 2021

ABSTRACT
During the Percy Sladen Expedition to Brazil in 1913 Professor J. P. Hill collected six specimens of land leeches, and while I was on leave from the Australian Imperial Force in France, and acting as Demonstrator in his department, he requested me to describe them. I was glad of this opportunity, for these leeches, themselves earthworm-like in appearance, were easy to determine as close relatives of Lumbrico-b d e 11 a, that interesting leech from Brazil, which has so closely copied the form and habit of an earthworm.
The Relation of the form of a Sponge to its Currents
Authors: Bidder G. P. 
Published: April 2021

ABSTRACT
All zoologists know that from the large holes, which we call oscula, on a sponge, an outgoing current may be detected in life. During several months in Naples I investigated this current, using litmus and carmine solutions, and carmine and indigo in suspension. I worked with two calcareous species of sponges, having oscula at the end of tubular prolongations, which reach the size and shape of a child’s thumb in the case of Leucaltis, and of a child’s finger in the case of Leucandra aspera (Text-fig. 1). The solutions were either placed on the surface of the sponge, to be sucked in by its currents (Text-fig. 2), or dropped by a pipette through an incision into the cloaca—the cavity of the tubular prolongation. In the latter case the time taken for the colour to be thrown out at the osculum, though liable to many corrections, afforded on the whole the most trustworthy determinations of oscular velocity: the cloaca being wider than the osculum, the observed cloacal velocity would be multiplied by 4, 5, or 6, as the case might be, to obtain the oscular velocity. A pretty method was arrived at accidentally (Text-fig. 3), when I found the coloured jet marked by dark beads or nodes, caused by my pulse shaking the pipette; the length between any two nodes, divided by three-quarters of a second, gives the core-velocity at that part of the jet.
The Golgi Bodies of a Coccidian
Authors: King Shana D. , Gatenby J. Brontë 
Published: April 2021

ABSTRACT
For many months we have been collecting material of the protozoan fauna of the gut of Lithobius forficatus. Our object was to study the Golgi apparatus, if such were present, and to examine also the behaviour of the mitochondria. We chose the form Adelea because we believed that its lifehistory was well known, and that there would be no special difficulty in identifying the stages. In this we have been disappointed—we found that Siedlecki and other workers have left the matter in a confused state : we have been obliged to spend many months trying to piece together the various parts of the life-history : at present we are not sure of any of the stages except those described in this paper.
Some Observations upon Spirostomum ambiguum (Ehrenberg)
Authors: Bishop Ann 
Published: April 2021

ABSTRACT
The genus Spirostomum was first mentioned by Ehrenberg, but no definition nor description was given. Its systematic position and the question of the number and identity of the species contained in it was a subject for discussion for many years. Later, Dujardin (7) gave a very satisfactory description of the genus in the following words :
Head Length Dimorphism of Mammalian Spermatozoa
Authors: Parkes A. S. 
Published: April 2021

ABSTRACT
Chromosome dimorphism of the spermatozoa has been shown for a variety of mammals, and in some cases this has been shown to be correlated with dimorphism in the head lengths of the spermatozoa. In the present paper this correlation has been extended to the spermatozoa of man, the mouse, and the rat, in which chromosome dimorphism of the spermatozoa had previously been shown, and in which head length dimorphism seems to exist. The interest of these results lies in the probability that the histological difference in the X- and Y-spermatozoa may account for the inequality of the sexes at conception in mammals.
On Brinkmann’s System of the Nemertea Enopla and Siboganemertes Weberi, n.g.n.sp.
Authors: Stiasny-Wijnhoff Dr. Gerarda , Leiden  
Published: April 2021

ABSTRACT
All text-books of zoology give the Nemertean system as Bürger published it several times in his monographs on this subject (6, 7, 8). The old systems of Schultze, McIntosh, Hubrecht have been forsaken, and our textbooks do not divide the Nemertini any more in Anopla and Enopla, or Palaeonemertea, Hoplonemertea, and Schizonemertea. The armature of the proboscis and the arrangement of the cephalic slits are believed to be of secondary importance, and Bürger divided the Nemertini into four orders, three of which, his Protonemertini, Mesonemertini, and Metanemertini are supposed to be closely related by having a body-wall that consists of an epithelium, a basement membrane, and two muscular layers. Benham, in Ray Lankester’s ‘Treatise on Zoology ‘, unites them as Dimyaria, and his Trimyaria consist of one order only, the Heteronemertini Burger. The Protonemertini are McIntosh’s family Carinellidae, Mesonemertini are his family Cephalotricidae and the genus Carino ma (Hubrecht) ; Metanemertini is a new name for Hoplonemertini (Hubrecht) or Enopla (Max Schultze), and Heteronemertini are Hubrecht’s Schizonemertini and his families Eupoliaidae and Valenciniaidae. Everybody agrees that the last two families are more nearly related to Lineids and Cerebratulids than to the Protonemerteans, and their enclosure in the order Heteronemertini seems to be well founded. The following schema gives the synonyms in the different systems.
Notes on Sporozoa parasitic in Tubifex: 1. The Life-history of Triactinomyxon Štoic
Authors: Mackinnon Doris L. , Adam D. Ines 
Published: April 2021

ABSTRACT
The Thames mud below Waterloo Bridge is full of reddish masses of small interlaced worms ; these are the oligochaetes Tubifex tubifex (Müll.) (= T. rivulorum Lmk.) and Limnodrilus hoffmeisteri Clap. While examining their gut-contents we found in Tubifex three species of that rare and little-studied organism Triactinomyxon Štolc, and having such large quantities of the host at our very doors we continued our search in the hope of elucidating some parts of the life-history.
Though we dissected 1,250 Tubifex we found the actinomyxidian only five times. This is approximately in agreement with Štolc’s statement that only one worm in 300 is infected. In three worms the infection was heavy, and in the other two it was comparatively light.1
On a new Prorhynchid Turbellarian from Tasmania
Authors: Hickman V. V. 
Published: April 2021

ABSTRACT
1. Prorhynehus tasmaniensis sp. nov. is found under alpine conditions in Tasmania.
2. It is allied to Prorhynehus putealis Haswell, but exhibits the following differences: (a) Larger size, (b) Posterior excretory canal does not bifurcate, (c) Female genital pore almost in line with excretory pores and below pharynx, (d) Female genital pore only one-eighth of body-length from anterior end. (Difference from all other members of the genus.) (e) Germo-vitellarium in middle line ventral to intestine. (f) Testis follicular, extending from the right side over the intestine on to the left side. (Difference from all other members of the genus.)
Note on the Amoeboid Elements in the Blood of Helix aspersa
Authors: Haughton Isabel 
Published: April 2021

ABSTRACT
Recently a considerable amount of work has been carried out in this laboratory by Gatenby, Duthie, Hill, and Macdougald on invertebrate tissue culture (4, 5, 6, 7, 8). Bohuslav also figured growths from various organs of Helix (1), notably the atrium (2). As the work quoted above has been done with species of Helix only, it is desirable at this point to notice and compare the behaviour of the leucocytes in the blood of Helix aspersa. Kollmann (12), by his comparative studies, demonstrated the homology of the leucocytes in all groups ; there is, therefore, no reason to suppose that the cell elements found in the blood are other than leucocytes.
Epiphysial Growth in the Branchial Skeleton of Fishes
Authors: Wheeler Haines R. 
Published: April 2021

ABSTRACT
The branchial bones of several bony fishes were studied in longitudinal section, and in one case a reconstruction model was made. A massive cartilaginous epiphysis lies partly enclosed within the shaft of the bone and partly beyond it. In the cartilage there can be distinguished a zone of undifferentiated cells lying beyond the bony shaft, a proliferative zone of flattened cells at the level of the end of the shaft, and a zone of hypertrophied cells no longer undergoing division enclosed within the shaft. In some cases there is a secondary centre of calcification in the zone of undifferentiated cells.
The mechanism of growth of the epiphysis and the formation of endochondral bone are similar to those found in the long bones of tetrapods, but in their details they are more simple in the fish.
Some remarks on North Atlantic Non-Pelagic Polystylifera
Authors: Stiasny-Wijnhoff Gerarda 
Published: April 2021

ABSTRACT
This publication contains the description of three previously but insufficiently known representatives of the former genus Drepanophorus, that live in the northern Atlantic Ocean. They are, together with the two species of Uniporus described by Brinkmann (1913), the only Beptantia that are known from the Atlantic. One of them, Punnettia splendida, lives in the English Channel, and was described by Keferstein and McIntosh as a distinct species, different from Hubrecht’s Drepanophorus rubrostriatus. Bürger included all these species in the Mediterranean D. spectabilis, and so did Riches and the author. After my publication on Mediter- ranean Polystilifera (1926), in which the Atlantic species as being separate was not mentioned, the late Professor McIntosh asked why I had been silent on this question. The present article gives my answer. The material has partly been collected by me in Plymouth, and partly consists in a series of sections from Professor Brinkmann.
The Germ-Cell Cycle in Phytophaga destructor Say
Authors: Metcalfe Margot E. 
Published: April 2021

ABSTRACT
The somatic cells in both sexes of Phytophaga destructor Say contain four pairs of V-shaped chromosomes, the sex-group being indistinguishable in size or form. The germ-cells in both sexes contain eight pairs of chromosomes. The maturation of the egg follows the normal course of development, eight bivalents being formed. After polar body formation the female pronucleus has eight chromosomes. The polar bodies are never extruded from the egg. Spermatogenesis is a complicated process, the details of which have not been satisfactorily determined. The growth stage appears to take place before the last spermatogonial division. No pairing of chromosome has been observed, and apparently no metaphase plate is formed at meiosis. Reduction is effected by the expulsion of two buds each containing four chromosomes. Thus only one sperm is produced from each spermatocyte. One or more sperms may enter the egg at fertilization. The germ-line is differentiated from the soma at the eightcell stage. At the fifth cleavage the somatic nuclei eliminate half their number of chromosomes, and are left with eight chromosomes. Migration of the germ nuclei takes place at the sixteencell stage. The relation of the chromosome numbers in the somatic and germ lines is discussed.
On the Formation of the Ground Substance of Loose Connective Tissue
Authors: lasswoin G. 
Published: April 2021

ABSTRACT
The formation of the ground substance of connective tissue has for long been one of the most controversial problems of histology. In spite of the diversity of the material studied, and of the methods of investigation used, there exists on this problem as yet no generally accepted view. Thus, we have at present several theories treating differently of the process of the formation of the ground substance and of its fibres.
The Spermatogenesis of Stenophylax stellatus, Curt. (Trichoptera)
Authors: Gresson R. A. R. 
Published: April 2021

ABSTRACT
The structure of the nuclei of the spermatogonia, spermatocytes, and the nuclear changes during the division of the spermatocytes are described. The nucleolus of the spermatocytes of Stenophylax does not contribute directly to the formation of the chromosomes as claimed by Lutman (8) for Platyphylax designatus. The diploid chromosome number of Stenophylax stellatus is sixty. The Golgi material of the spermatogonia and of the early primary spermatocytes is in the form of a dense mass; in the primary spermatocytes this mass separates to form two masses. The Golgi material of the spermatogonia and spermatocytes breaks up to form Golgi bodies which move towards the poles of the spindle, and are thus distributed with approximate equality to the resulting cells. Granular mitochondria are present in the spermatogonia; during the metaphase they are distributed throughout the cytoplasm. During the division of the spermatocytes the mitochondria come together to form two masses at the side of the spindle; in the telophase these masses are separated into two approximately equal parts. The acrosome is formed under the influence of some of the Golgi material; after its formation the Golgi material breaks up into smaller bodies which become distributed through the tail region. The mitochondria, in the form of a tangled mass of filaments, become arranged around the axial filament; later they form a compact sheath. A vesicle makes its appearance in the nucleus of the young spermatid and increases in size, but later becomes smaller and finally disappears. A structure which is probably a post-nuclear body was observed in the young spermatid.
The Embryonic Development of the Stick- Insect, Carausius morosus
Authors: Thomas A. J. 
Published: April 2021

ABSTRACT
The maturation of the egg takes place in the ovarian tube, and is immediately followed by the formation of the cleavagenucleus and its division into many nuclei. The entire products of the cleavage-nucleus migrate to the surface to form the blastoderm. Cleavage of the yolk was not observed even in late stages. Yolk-cells are absent when the blastoderm is being formed. Primitive endodermal cells are proliferated from the middle of the germ-band, and form a membrane between the germ-band and the yolk. The membrane is present only in embryonic stages ; some of the cells proliferated wander into the yolk and act as vitellophags. Mesoderm is formed by proliferation of cells from the ventral plate. It is preceded by the formation of a shallow gas- trular furrow, and from the bottom of this furrow proliferation takes place. The mesoderm becomes arranged in segmental masses. Two masses of cells proliferated at the anterior and posterior ends of the germ-band are shown to be the endodermal rudiments from which the mid-gut epithelium is formed. The invaginations of the stomodaeum and proctodaeum grow against these masses and carry parts of the proliferating areas near their blind ends. It is shown that the various methods of mid-gut formation which have been described could be reconciled with the process described in Carausius. The hinder end of the mid-gut is flanked by two plates of ectoderm which are forward extensions of the proctodaeum. Into these extensions the Malpighian tubules open, and, as their histology is identical with that of these extensions and widely different from that of the mid-gut, these tubules must be ectodermal in nature. The formation of the amnion and serosa are described.
On the Nature of the Free Cell-Border of certain Mid-Gut Epithelia
Authors: Newell G. E. , Baxter E. W. 
Published: April 2021

ABSTRACT
The terms cilia, rod-border, brush-border, and other terms used in this paper are defined. The epithelium lining the mid-gut of Melinna is described with special reference to the cell-border. Variation between different regions of the gut are noted. There are two main types of epithelia: (i) ciliated, (ii) rod-bordered. The presence of a peritrophic membrane in the middle region of the stomach is noted. A description of the mid-gutepithelium of Locust a and Chironomus is given, and the essential similarity between the brush-borders of the two is stressed. The ciliated effect described by Vignon in Chironomus is shown to be due to the presence of motile bacteria. From a thorough survey of the literature and from our own observations, it is concluded that there are two main types of cell-borders: A. Motile, i.e. ciliated; with which basal corpuscles, derived from division of the centrosomes, are always associated.B. Non-motile.—It is held that these are of two distinct types: (i) Rod-border, where the elements are probably homologous with the basal segments of cilia. This type occurs in Melinna, Lumbricus, and probably in other animals, and it is possible that the striated free border found in the epithelium of the vertebrate intestine is of a somewhat similar nature.(ii) Brush-border, where the elements are simple filaments and bear no relation to cilia. This type is found typically in insects and in a slightly modified condition in the uriniferous tubules of vertebrates. Both motile and non-motile elements lie above the free surface of the cell which is marked by the limiting membrane. Mention is made of the brush-border epithelium of the Malpighian tubules of insects.
The Effect of Ultra-Centrifuging Vertebrate Neurones
Authors: Brown R. H. J. 
Published: April 2021

ABSTRACT
The Golgi apparatus may appear as a network or incomplete reticulum; it is lighter than the other cytoplasmic inclusions but its form makes its displacement difficult. Its parts never approach the periphery of the cell. The neutral-red bodies have no part in its composition. There exists a separate canalicular system which is connected with the surface of the cell, and otherwise is of similar dimensions to the Golgi apparatus. It is thought to represent the trophospongium of Holmgren. It is unaffected by the centrifuge. The vacuome appears in the form of isolated granules which can be osmicated after staining in neutral red. They are lighter than the cytoplasm and are separate from the Golgi apparatus, though on account of their similar density they are thought to have some spatial connexion with it. The mitochondria are in the form of rods and granules which are very slightly denser than the cytoplasm, and show no evidence of having any connexion with the Golgi apparatus. The Nissl substance occurs as large irregular bodies in the fixed material. It is thought to be in a diffuse form in the living cell. It is much denser than the cytoplasm.
Two Polymastigote Flagellates of the Genera Pseudodevescovina and Caduceia
Authors: Kirby Harold 
Published: April 2021

ABSTRACT
The previously published description of Pseudodevescovina uniflagellata from Kalotermes (Neotermes) insularis is incorrect in practically all points. The flagellate is a devescovinid which, like other members of the subfamily, has three anterior and one trailing flagellum. The trailing flagellum is relatively small and slender. The most unusual characteristic is the parabasal apparatus, which consists of a C-shaped or L-shaped main limb adjacent to the nucleus and seven to nineteen cords attached to the transverse portion of this. A sinuous movement of the cresta has been observed in living material. The flagellate moves forward steadily with considerable vigour as compared to Devescovina lemniscata and even Stephanonympha with its hundreds of flagella. Yet the small trailing flagellum seems to be the main cause of this movement, as the anterior whip often is turned back against the body and trailed. This suggests that increase in size of the trailing flagellum, which is a broad ribbon in Devescovina lemniscata, or increase in number as in Stephanonympha, does not necessarily enhance the locomotor efficiency of the flagellate. The body is completely covered with a dense investment of relatively short spirochaetes, the ends of which appear actually to be embedded in the cytoplasm and, taking an iron-haematoxylin stain, simulate basal granules. There are eight chromosomes, which can be recognized most clearly when they are granules or short, stout rods in the early telophase. At the beginning of binary fission, the main limb of the parabasal apparatus breaks. A portion of length about equal to that of the nucleus is left attached to the centriole at one pole of the spindle; at the other pole a parabasal develops d e novo, doubtless in connexion with the centriole. This is at first a filament, which reaches a size equal to the part of the old parabasal that remains attached, then both grow equally. After division of the body, new cords grow out from this main limb. The detached part of the old parabasal apparatus breaks up into successively smaller vesicular bodies, which are noteworthy for a deeply staining cap sharply distinguished from the chromophobe substance, appearing like diagrams of dictyosomes. These fragments are resorbed before plasmotomy. Grassi’s Devescovina nova has been found in the species of termite from which he described it, Kalotermes (Neotermes) erythraeus from Eritrea. Its characters indicate that it must be removed from Devescovina, and it has been placed in the genus Caduceia. The parabasal apparatus consists of a main limb, which in this case is loosely spiralled around the trunk of the axostyle, and from one to six attached cords directed more or less parallel to it.
On the Ciliary Mechanisms and Interrelationships of Lamellibranchs: PART IV: Cuticular Fusion, with special reference to the Fourth Aperture in certain Lamellibranchs
Authors: Atkins Daphne 
Published: April 2021

ABSTRACT
A form of fusion involving only the cuticle has been found in certain Lamellibranchs between the outer demibranchs and the mantle or the visceral mass; between the two inner demibranchs; and, in forms possessing a fourth aperture, between the mantle lobes in the mid-ventral line between this and the pedal aperture. The histological structure of the junction is described, and is especially considered in relation to the condition of the fourth aperture in the Solenidae.
Microscopic Illumination
Authors: Smith Edwin 
Published: April 2021

ABSTRACT
It is often difficult to obtain an equally illuminated field for both eyes when a half-inch object-glass is employed with the binocular. The prism causes the field to be darkened on opposite sides for the two tubes of the body. This defect becomes more apparent when the lenses of the object-glass are further separated from the prism by the additional thickness of the nose-piece. Diffusing the light with ground glass partly remedies the defect, but not entirely; moreover, diffused light is not suitable for many objects, where definite shadows are desired for the purpose of displaying structure. I find, however, that an achromatic combination with wide aperture as condenser, and a half-inch mounted in short cells, completely satisfy the conditions of the problem, and I am now able to employ the half-inch binocularly with perfect ease, by night or day.