bluuebunny/crossref_metadata_2025_split huggingface dataset:
Description of an Apparatus for Maintaining a Constant Temperature under the Microscope
Authors: Schäfer E. A. 
Published: April 2021

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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.
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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. †
The Development of Lepidosiren paradoxa
Authors: Kerr J. Graham 
Published: April 2021

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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

ABSTRACT
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.
Observations on the Amœbæ in the Intestines of Persons Suffering from Goitre in Gilgit
Authors: McCarrison Robert 
Published: April 2021

ABSTRACT
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

ABSTRACT
[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

ABSTRACT
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.