bluuebunny/crossref_metadata_2025_split huggingface dataset:
Yolk-Absorption in Loligo and the function of the embryonic liver and pancreas
Authors: Portmann Ad. , Bidder Anna M. 
Published: April 2021

ABSTRACT
Although many details of Cephalopod development have long been known to biologists, the physiology of the developing animal was, for many years, practically unstudied. The method by which the yolk is absorbed was, in particular, completely unknown. Faussek, in his paper of 1901, summarized the knowledge then existing, and so few have been the additions of later years that, in the brief abstract now given, we follow him almost verbatim.
The Cytoplasmic Inclusions of Certain Plant Cells
Authors: Patten Ruth , Scott Margaret , Gatenby J. Brontë 
Published: April 2021

ABSTRACT
The plant cell has the following cytoplasmic inclusions : (a) Mitochondria (chondriome). (b) Plastids (plastidome), probably derived from mito chondria. (c) Golgi elements (osmiophilic platelets of Bowen). Plant cells often contain vacuolar spaces filled with a watery fluid. These spaces are sometimes canalicular in arrangement, as shown by Bensley eighteen years ago. There is no evidence that these vacuoles are : (a) Formed from self-perpetuating primordia. (b) Possessed of a lipoid membrane. (c) Associated with the Golgi elements (platelets). There is no reliable evidence that the plant-cell cytoplasm contains any type of protoplasmic inclusion not also found in animal cells, for the plasts are probably enlarged mitochondria, as has been suggested by Mottier, Guilliermond, and others. The so-called ‘vacuome ‘drawn by Bowen (this paper, p. 391) is found almost always in Weigl (Mann-Kopsch) preparations. Such ‘vacuoles ‘and primordia are possibly corro-sive-osmic artefacts caused by the non-ability of water to wash out the corrosive sublimate of the Mann’s fluid, previous to osmication. The osmiophilic platelets are demonstrable by the Kolat-chev and Mann-Kopsch methods, but we have not so far succeeded in showing them with Benda, Flemming-without-acetic, haematoxylin, Champy-haematoxylin, or the silver-nitrate Golgi methods. They resemble closely the dictyosomes of Hemipterous germ cells.
Arcella: A Study in Cell Physiology
Authors: Bles Edward J. 
Published: April 2021

ABSTRACT
The experimental work described in the following paper was carried out, and, in the main, completed during the years 1910—13. But an earnest endeavour to interpret the facts aright, leading gradually to the personal views expressed in the later chapters of the paper, occupied the author’s mind almost up to the day of his untimely death in 1926. His work and thought suffered, however, frequent and long interruptions due to serious illness. Had not his activities been grievously inhibited by that failure of health, further experiments suggested from time to time by his maturing thought about his problem would certainly have been made ; while the results of his work and the conclusions arrived at would have been published long ago.
On the Development of the Skull of Leptodeira hotamboia
Authors: Brock Gwendolen T. 
Published: April 2021

ABSTRACT
Accounts of the development of the Ophidian skull are not numerous. Rathke as early as 1839 described the development in Coluber natrix from a macroscopic point of view. Parker (1878) gave a full description, excellently illustrated, of Tropidonotus natrix, but his work is out of date and it is evident that he was misled in several points, especially over the condition of the orbito-temporal region. He does not appreciate the reduced state of the side-wall in this region, and claims to have identified both an orbito-sphenoid and an alisphenoid. Gaupp makes many valuable contributions to the understanding of the snake skull, but, as he had only a single specimen of a Tropidonotus natrix embryo, he was unable to settle definitely the doubtful points in Parker’s work. Peyer in 1912, with the intention of bringing Parker’s work up to date, gave an excellent account of the stages of development in Vipera aspis, but he failed to settle the problem of the orbito-temporal region satisfactorily. De Beer (1926), in his work on the orbito-temporal region, discussed the problem of the ophidian alisphenoid in the light of the present-day understanding of that bone, but had only one specimen of Tropidonotus and one of Pseudechis at his disposal. He suggested that I should undertake a full investigation of the developmental stages. The work was begun primarily in the hope of reaching a solution to the vexed problem of the ‘alisphenoid ‘. In the course of the investigations several interesting points have come up: the NO. 290 uposterior attachment of the nasal capsule, the probable absence of an extracolumella and the nature of the columella attachment to the quadrate; the homology of the fenestra cochleae.
The Oogenesis of Lumbricus: a Restatement
Authors: Harvey L. A. 
Published: April 2021

ABSTRACT
My former results (1925) have been revised, and the following are now recorded:
The mitochondria are filamentous and granular. They are present in the oogonia as a cap over one pole of the nucleus.
This cap enlarges as the oocyte grows, and finally breaks up and spreads as loose clouds over the entire cytoplasm. Under darkground illumination the mitochondria appear as areas showing a milky scintillation, owing to Brownian movement.
The Golgi bodies are in the form of curved rodlets tapering towards each end and having a patch of sphere material on the concave side. The rodlet only is visible in living cells. Darkground illumination fails to differentiate the Golgi elements from the ground cytoplasm. It is uncertain whether they are derived from one only or more than one Golgi body in the oogonium.
Droplets containing weak fat are present in all older oocytes, and in some ovaries in the younger cells, even being present in oogonia. They arise de novo in the cytoplasm.
The vacuome in this material is a function of the cell’s reactions to neutral red, and is not present in the unstained egg. It arises in close relation to the Golgi apparatus, but in later phases of staining wanders away from it.
Nath’s observations on earthworm eggs, and his theory of the vacuolar nature of the Golgi body, are discussed in detail.
On the Autonomic Nervous System of the Teleostean Fish Uranos copus scaber
Authors: Young John Z. 
Published: April 2021

ABSTRACTThe sympathetic ganglia of Uranoscopus resemble those of mammals in that they are connected with the spinal nerves by white rami consisting of medullated (pre-ganglionic) fibres, and grey rami of non-medullated (post-ganglionic) fibres. The sympathetic ganglia are connected together by a chain in which the medullated fibres may run forwards or backwards and may also cross in transverse commissures to the opposite chain. No sympathetic nerves to the heart were found. The cardiac nerves spring from the vagus and consist of medullated fibres. The gonads and the mesonephros and its derivatives (kidneys, urinary bladder) receive nerves only from the sympathetic system, with the exception of the sphincters round the external openings of the gonads and bladder which are innervated by branches of the spinal nerves. There is, on each side, only a single anterior splanchnic nerve from the sympathetic system to the gut; there is therefore nothing corresponding to the pelvic nerves (sacral parasympathetic outflow) of Tetrapods. The sympathetic chain extends into the head and bears sympathetic ganglia in connexion with the vagus, glossopharyngeus, facialis, and trigeminus nerves. The rami communicantes between these sympathetic ganglia and the cranial nerves consist almost entirely of non-medullated (post-ganglionic) fibres; the pre-ganglionic fibres for these ganglia run out in the white rami of the third and fourth spinal nerves and thence forwards in the sympathetic chain. The ciliary ganglion resembles that of mammals, receiving fibres from the trigeminal sympathetic ganglion (radix sympathica), profundus ganglion (radix sensoria) and oculomotor (radix brevis). The sympathetic fibres in the long and short ciliary nerves (though post-ganglionic) are medullated. There is a bundle of fibres running from the trigeminal sympathetic ganglion via the radix longa and radix brevis to the oculomotor nerve. There is a separate profundus ganglion in Uranoscopus from which a small nerve passes to join the trigeminus (portio ophthalmica profundi?) while larger branches run to the long and short ciliary nerves.
On the Function of the so-called ‘Rectal Glands’ of Insects
Authors: Wigglesworth V. B. 
Published: April 2021

ABSTRACT
It is a characteristic of those animals, such as birds and reptiles, which eliminate their nitrogen in the form of uric acid, that they show an active reabsorption of water from the excrement in the cloaca; so that there is a continuous circulation through the excretory system, enabling the animal to accomplish its excretion with a minimal supply of fluid. In the large bowel of mammals, also, the water secreted in the digestive juices is reabsorbed, and the faeces rendered more or less dry before they leave the body.
The Histochemical Recognition of Certain Guanidine Derivatives
Authors: Baker John R. 
Published: April 2021

ABSTRACT
1. A review of known facts indicates that Sakaguchi’s test gives a positive reaction with all substances having this formula (and with no others):
where α is H or CH3 and β is also H or CH3.

2. Arginine, being a constituent of most proteins, is by far the commonest positively-reacting substance that occurs in the tissues of plants and animals. Galegine and agmatine, which also react positively, are of very restricted occurrence.
3. Details are given of a method whereby Sakaguchi’s test may be applied to paraffin sections.
Ester Wax: A New Embedding Medium
Authors: Steedman H. F. 
Published: April 2021

ABSTRACT
Ester wax is a new ribboning embedding medium. It consists of five substances which may be varied in proportion so that media of different characteristics may be produced. A mixture which will meet most requirements is as follows:

The following facts relate to this mixture:
Melting-point. 46-8° C.
Section range. 2-20 μ at a room temperature of 64° F.
Ribbon range. 2-15 μ at a room temperature of 64° F.
Final compression loss. 7·6 per cent, at 10μ (after flattening).
Solvents. Alcohols, ethers, esters, ketones, hydrocarbons, aldehydes, chlorinated hydrocarbons, natural oils, &c.
Cutting. This must be done more slowly than with paraffin wax.
Flattening. Sections may be flattened on tap-water or aqueous staining solutions. Flattening must be completed in a drying oven at 40-5° C. with sufficient water under the sections to float them.
Staining. Two methods: (1) In the ribbon; (2) As for paraffin wax sections.
Pre-mounting fluid. Xylene, benzene, ligroin, &c.
Mounting fluid. ‘Sira’, or Kirkpatrick and Lendrum’s polystyrene mounting medium.
Conclusion. It is believed that ester wax may open up new methods in histology and cytology. Its greater water tolerance and its property of ribbon staining followed by drying constitute an advantage found in no other embedding medium. Greater use of the wide range of solvents as stain carriers is indicated.
A Quantitative Study of the Osmium Impregnation of the Contractile Vacuole of Chilomonas paramecium (Cryptomonadina)
Authors: Smyth J. D. 
Published: April 2021

ABSTRACT
1. Examination of the contractile vacuole of Chilomonas paramecium during progressive impregnation by the Weigl osmic technique revealed that the so-called ‘osmiophil cortex’ appeared first as a number of perivacuolar osmiophilic granules. Prolonged impregnation caused these to fuse to form a closed ring which, after very prolonged incubation, became a solid osmiophilic mass.
2. Cultures fixed together and osmicated in separate tubes gave more consistent impregnations, in any one series, than those both fixed and osmicated separately.
3. With the two samples of osmium tetroxide used, after normal fixation, A consistently gave impregnations of 62-85 per cent., and C impregnations of 25-36 per cent.
4. Constant mixing during fixation and osmication was not advantageous, and gave more irregular results than normal methods.
5. Time of fixation, between the limits of 5’ to 90 minutes, had no effect on the impregnation.
6. It was suggested that the irregularities of impregnation with a given sample of osmium tetroxide were due to the presence of a trace of some retarding agent, possibly introduced at the time of fixation.
7. It was shown that the osmiophily of the perivacuolar region in Chilomonas did not vary with the vacuolar phase.
On the Structure, Division, and Systematic Position of Trichomonas vaginalis Donné, with a Note on its Methods of Feeding
Authors: Hawes BY R. S. 
Published: April 2021

ABSTRACT
1. Trichomonas vaginalis has been cultivated on various media and a simple method of maintaining cultures on Boeck and Drbohlav’s egg-Ringer-albumen medium is described.
2. The feeding methods of the flagellates in culture have been studied and some evidence of extracellular digestion is recorded.
3. When cultivated on media deficient in carbohydrate, T. vaginalis is reduced to the dimensions of T. hominis, but when adequately fed it maintains its distinctively larger size. Out of forty-eight strains of T. vaginalis, only two developed in culture the long undulating membrane and free posterior flagellum typical of T. hominis in nature.
4. The structure of T. vaginalis has been reinvestigated, (i) It differs constantly and significantly from the intestinal trichomonads of man in size, nuclear organization, and the form of the axostyle and basal fibre, (ii) It also differs from T. hominis in the characters of its parabasal apparatus and cytoplasmic inclusions, and, in nature, in the length of its undulating membrane and in lacking a free posterior flagellum, but for reasons discussed in the text these points are at present considered less reliable in diagnosis than those given under-4 (i).
5. It is concluded that T. vaginalis is a species distinct from all other human trichomonads.
6. The method of division has been described. In general, it follows the same course as T. hominis, but separation of the old, and growth of the new, cytoplasmic structures occurs somewhat later in T. vaginalis, and the old axostyle is retained throughout division. There are five chromosomes, formed during prophase from aggregations of extra-karyosomatic granules.
The Cytology of the Neurones of Helix aspersa
Authors: Thomas Owen Lewis 
Published: April 2021

ABSTRACT
Within recent years the important investigations of Parat (1928), Hirsch (1939), Worley (1943), and Baker (1944) have extended our knowledge of the form, function, and cyclical activity of the intracellular organoids, more especially with regard to the so-called Golgi apparatus.
Further Remarks on the Histochemical Recognition of Lipine
Authors: Baker John R. 
Published: April 2021

ABSTRACT
In an earlier paper (Baker, 1946), a technique was described for the histochemical recognition of lipine. This technique was called the acid-haematein test. It was shown that lipines, after appropriate fixation and subsequent mordanting with potassium dichromate, display a special affinity for hae?atein, with which they react to give a blue, blue-black, or grey colour. If certain precautions are taken, lipines can thus be distinguished from other substances occurring in the tissues of plants and animals. It was found, however, that the crude galactolipine used in the investigation reacted much less strongly than lecithin, cephalin, and sphingomyelin. It will be recollected that galactolipine differs from these other lipines in containing no phosphoric acid radicle. The suggestion was made that if the galactolipine used in the test had been completely free from contamination with sphingomyelin, it might have proved negative to the test. If so, the acid-haematein test would be a test not for lipines in general, but for lipines other than galactolipines; that is to say, it would be a test for phospholipines. It is the purpose of the present paper to report the reaction of purified galactolipine.
The Structure and Deposition of the Cuticle in the Adult Mealworm, Tenebrio molitor L. (Coleoptera)
Authors: Wigglesworth V. B. 
Published: April 2021

ABSTRACT
In three earlier papers (Wigglesworth, 1933, 1945, 1947a) the structure and deposition of the cuticle of Rhodnius prolixus have been described. The main conclusions reached were as follows. The epicuticle is a composite structure made up of four layers: (i) a ‘cuticulin’ layer composed of a condensed lipoprotein subsequently tanned by quinones; (ii) a layer of material rich in dihydroxyphenols; (iii) a thin layer of crystalline, orientated wax molecules responsible for the waterproofing of the cuticle (cf. Beament, 1945); and (iv) an outermost ‘cement’ layer protecting the wax.
Studies on Lagenophrys tattersalli (Ciliata Peritricha, Vorticellinae) Part II. Observations on Bionomics, Conjugation, and Apparent Endomixis
Authors: Willis A. G. 
Published: April 2021

ABSTRACT
A study of the bionomics of L. tattersalli shows that the initial infection of the host is by the passage of swarmers from the gill-plates of the female host to those of the embryo in the brood-pouch. The transmission of the infection from instar to instar is about 50—70 per cent, effective. It is brought about by (i) the mobilization of the entire colony at ecdysis by an obligatory type of division (second-type division), and (ii) by the penetration of the swarmers to the surface of the new instar through splits which appear in the old cuticle as it is shed. The term ‘protoconjugant’ is applied to the organism from which the two microconjugants are formed by binary fission. The protoconjugant is formed by the unequal fission of the parent, and not by budding as in L. platei (Ubisch, 1913). The divisions which produce the proto- and micro-conjugants are compared with the normal asexual reproductive process (first-type division, Willis, 1942). The conjugation process is described. In view of the early fusion of both conjugants, the term ‘synconjugant’ is proposed for the macroconjugant after its fusion with the microconjugant. There are no visible nuclear preparations for conjugation in either conjugant before their attachment. The evidence for a state of ‘Conjugationserwartung’ (Ubisch, 1913) is criticized and shown to be based, in all probability, on specimens produced by the distributive divisions of the synconjugant. The term ‘necrochromidium’ is proposed for the mass of vesicles formed by the degeneration of the macronucleus in conjugation and endomixis. Before the formation of the necrochromidium the macronucleus of the macro-conjugant becomes elaborately branched. The distributive divisions of the synconjugant are described for the first time. Resemblance to other vorticellinids is shown during the intermoult period of the host. At ecdysis, the distribution of the nuclear Anlagen is adapted to the obligatory second-type divisions which are undergone by L. tattersalli at this period. In some cases one of the divisions of the synkaryon is cytoclastic. A process of apparent endomixis is described. In this process unequal fission produces a small organism, resembling a protoconjugant which fails to separate, and a larger organism. The micronucleus of the smaller organism remains undivided and soon degenerates. The micronucleus of the larger organism undergoes two successive divisions to form four nuclear Anlagen. An anomalous process of micronuclear division and reduction is described. One of the micronuclei produced by the division passes into a small bud of protoplasm. Later the latter falls off and degenerates.
The Golgi Material and Mitochondria in the Salivary Glands of the Larva of Drosophila melanogaster
Authors: Hsu W. Siang 
Published: April 2021

ABSTRACT
The salivary glands in the larvae of Drosophila show evidence of serving two functions: (1) production of digestive secretion, (2) accumulation of reserve food for the period of pupation. The two functions proceed simul- taneously within the same cell during certain stages of its development. A single droplet of digestive material has been seen to originate and grow within each Golgi body in the gland-cells. When a certain size is reached the droplet is released into the cytoplasm and by the fusion of two or more of them bigger vacuoles are formed. The secretory material is discharged into the lumen by means of a merocrine mechanism. Neither mitochondria nor nucleus has been observed to take any visible part in the elaboration of secretion droplets. The storage granules found in older and larger cells have been observed to be direct transformations of chondriomites, and neither the Golgi material nor the nucleus shows any sign of participation in the formation of these granules. From the standpoint of morphology and behaviour, the Golgi bodies found in the salivary gland cells are the same as found in the cells of the glandular portion of the proventriculus and the epithelium of the anterior portion of the midgut of the larva. My observations do not lend themselves convincingly to a two-compo- nent conception of the structure of Golgi bodies.
A Simple Method for Orientating Small Objects for Sectioning, with Special Regard to Nematodes
Authors: Overgaard C. 
Published: April 2021

ABSTRACT
For solving certain anatomical problems in free-living nematodes serial sections are necessary. Various methods of orientation proved unsatisfactory for these small objects (in this case 700μ. in length and 30μ in width). The following method was worked out and found excellent:
The Mechanism of Insemination and the Mode of Action of the Spermatophore in Gryllus domesticus
Authors: Khalifa A. 
Published: April 2021

ABSTRACT
The house cricket spermatophore is largely protein and does not contain any chitin. It is composed of an ampulla, a handle, and a long capillary tube terminating in a pointed closure.
The wall of the ampulla comprises four different layers: an outer thin layer, an evacuating fluid, a thick strong inner layer, and a transparent inner membrane. In between the inner layer and the inner membrane, at the top of the cavity, there is the pressure body, a protein mass, divided into two halves. Each half is surrounded by a thin membrane.
The process of emptying a spermatophore is due to osmosis. It has been shown experimentally that the strong inner layer of the ampulla acts as a semi-permeable membrane separating two fluids of different osmotic pressure —the evacuating fluid and the pressure body. When the closure at the tip of the tube is removed, the pressure body swells, exerting a pressure on the sperm as the evacuating fluid passes inwards.