bluuebunny/crossref_metadata_2025_split huggingface dataset:
Note on the Reproductive Organs of the Cheilostome Polyzoa
Authors: Huxley T. H. 
Published: April 2021

ABSTRACT
Obvious as are the ovicells and partially-developed ova of the cheilostome Polyzoa, the precise position of their ovaria and testis has not yet been determined ; the general idea that the ova are developed within the ovicells being wholly an assumption. The investigation of the question is not without difficulty, on account of the delicacy of the ova in their young condition, the greater or less opacity of the ectocyst, and the obstruction offered by the other viscera if the cells be viewed in any of the positions which they ordinarily assume, lying, that is, on their front or back faces. By tearing up a polyzoarium, with needles, into single series of cells, and causing one of these series to lie upon its side, I found the process of examination much facilitated.
On an Easy Method of viewing certain of the Diatomaceæ
Authors: Hall John Charles 
Published: April 2021

ABSTRACT
We shall most certainly add not a little to the chances of increasing our knowledge of the intimate structure of the infusorial tribes, if any means can be suggested by which the number of observers may be increased. Possessed of a good microscope by one of our principal makers, a student may imagine that he is in a condition at once to ascertain the exact form and nature of certain shells of Bacillaria, certainly amongst the most difficult of test objects ; a very few trials will, however, convince him that even the best-constructed eighth will not fully display their peculiar markings without some accessory instrument. For this purpose the achromatic condenser of Mr. Gillet, as made by Mr. Ross, or the achromatic condenser of Powell and Lealand, or of Smith and Beck, is usually employed. The purse, unfortunately, of the most enthusiastic labourers is not always the heaviest ; a microscope is bought and added to from time to time, and the condenser, so much coveted, must often be waited for some years.
Further observations on the genus triceratium, with descriptions and figures of new species
Authors: Brightwell T. 
Published: April 2021

ABSTRACT
In June, 1853, I communicated to this Journal a paper on the genus Triceratium, with descriptions and figures of 22 species. Since that time, I have used my best endeavours to add to my knowledge of these singular forms, and have nearly doubled my list. Those not before described I purpose to describe in this paper, adding figures of each species, and shortly to notice such as other labourers in the same field have made known. I take this opportunity, also, to correct some errors in my former paper.
On Some Points in the Structure and Physiology of certain Fungi, with notices of the occurrence of some species new to this country
Authors: Currey Frederick 
Published: April 2021

ABSTRACT
The object of the present communication is sufficiently described in the title given above. Being the result of a number of observations made at various times, the paper may appear to some extent discursive and unconnected, but I venture to hope that the facts recorded will be considered of some scientific value. Such of the subjects as required illustrations to render the discussion of them intelligible, are figured in the accompanying plate from drawings made (with the exception of figs. 42, 43) with the Camera lucida.
Empusa Muscæ, and the disease of the Common House-fly. A contribution towards the knowledge of Epidemics characterised by the presence of parasitic Fungi
Authors: Cohn Breslau Dr. F. 
Published: April 2021

ABSTRACT
The subject of this paper is the well-known, curious disease which prevails among common house-flies, at the period when the departing warmth of autumn induces them to seek shelter within doors.
Ueber die Entwickelung und den Bau des Säugethierzahns
Authors: Hannover Von Dr. Adolph 
Published: April 2021

ABSTRACT
In this beautifully illustrated memoir, Dr. Hannover contributes much interesting information with regard to the histology of the dental tissues in the Mammalia generally; but we suspect that both by the author, and by the scientific public, the pith of the essay will be considered to lie in the views respecting the development of the teeth, whose exposition occupies so large a portion of it. It is to these, therefore, that we shall chiefly direct the reader’s attention in the course of the following critical analysis. Dr. Hannover commences his work thus:
An Adjustable Index Point for the Scale to be used as a Marker
Authors: Bridgman W. K. 
Published: April 2021

ABSTRACT
In carrying out the principles laid down by the committee appointed by the council of the Microscopical Society, I have succeeded in producing an arrangement capable of doing double duty—serving as a “marker,” and, at the same time, being an index to the scale as a “finder ”—so that either or both may be used upon the same object at any time without requiring a separate carrier, or interfering with any of the arrangements either of the slide or the object-glass.
On a True Parthenogenesis in Moths and Bees, a contribution to the history of Reproduction in Animals
Authors: Von Siebold Carl Theodor Ernst , Dallas William S. 
Published: April 2021

ABSTRACT
The whole theory of reproduction, as it occurs in plants and animals, has undergone curious and interesting changes, according as new observations have been made from time to time. Amongst the earlier naturalists sex was only recognised amongst the higher animals, and the lower animals and plants were supposed to be produced by a process of budding. Gradually, however, it became evident that amongst the lower animals sexes existed, and at length the discovery was made of the true relations of the pollen of plants to the ovules contained in the pistil. Then followed the sexual system of Linnæus. But Linnæus was not aware how far the antagonistic cells existed amongst the lower plants, and it has been the discovery of microscopists of recent times that sperm-cells and germ-cells exist in the Linnean Cryptogamia. So far have these discoveries been extended in both the animal and vegetable kingdom, that it would appear to be a general law that no true species of animal or plant is renewed without the union of sperm-cells and germ-cells. But whilst these observations were going on, many curious instances of anomalous production of individuals were observed. Steenstrup drew attention to the fact that many animals, whilst passing from their youngest to their adult forms, produced new individuals without any union of germ-cells and sperm-cells. Such animal forms he called “nurses.” Professor Owen observed the phenomenon of “nursing” with great care in the well-known plantlouse (Aphis). In these creatures, the young, generated by the union of the sperm-cell and the germ-cell, produce young, resembling themselves, for eight or nine generations without any union of the two opposite cells. This Professor Owen calls Parthenogenesis.
On the crystals contained in the malpighian vessels of caterpillars
Authors: Schlossberger J. 
Published: April 2021

ABSTRACT
In the Malpighian vessels of a caterpillar (Eichenspinneraupe) the microscope showed the contents to consist of numerous, brilliant, and colourless crystalline corpuscles, of very various sizes, although the largest were scarcely equal to the quadratoctahedra of oxalate of lime which occur in human urine. Most of these minute crystals were isolated; but here and there might also be remarked crystalline masses, in which the individual crystals were united by an amorphous or membranous connective material. The isolated corpuscles never presented more than one surface to view, which was for the most part quadratic, though in some cases having an oblong form. No octahedra could be observed.
How to work with the microscope
Authors: Beale Lionel S. 
Published: April 2021

ABSTRACT
Few men have worked more diligently and successfully with the microscope than Dr. Beale, and none have more claims to be heard on its uses and the methods of its application. Although we have had many works devoted to the microscope, to explanations of its structure, and the objects it investigates, we think with Dr. Beale that a book with a more thoroughly practical aim was really a desideratum. It is this hiatus in our literature which Dr. Beale has attempted in the present work to fill up. The instruction conveyed is in the form of lectures, which were, in fact, delivered by the author during the winter session of 1856-7. He offers the following apology for his little book :
On the Detection of Strychnia by the formation of Iodostrycknia
Authors: Herapath W. Bird 
Published: April 2021

ABSTRACT
My Dear Sir,—Will you do me the favour to announce to the Royal Society, that I have been engaged during some time past in the application of my discovery of the optical properties of iodo-strychnia to the detection of this alkaloid in medico-legal inquiries? I find it perfectly possible to recognize the 10,000th part of a grain of strychnia in pure solutions by this method, even when experimenting on very minute quantities. In one experiment I took 5th of a grain only, and having produced ten crystals of nearly equal size, of course each one, possessing distinct and decided optical properties, could not represent more than the Tu th part of a grain; in fact, it really represents much less, inasmuch as one portion of the strychnia is converted by substitution into a soluble hydriodate, and of course remains dissolved in the liquid.
On the Aquarium
Authors: Warington Robert 
Published: April 2021

ABSTRACT
The speaker opened the evening’s demonstration, by stating that he had immediately responded to the invitation of the managers of the Royal Institution to deliver this discourse, on what they had been pleased to call his “own subject,” from the feeling, that as the originator of the aquarium, he was in duty bound to afford, to all those who had taken up this “new pleasure,” every assistance, from the result of his own experience, that lay in his power, in order to render the undertaking more easy and pleasurable ; and for this purpose he proposed to lay before his audience, as far as was practicable, a demonstration of the principles on which it was founded, particularly as very erroneous ideas had been promulgated on the subject, and instructions given in several most engaging publications, which might tend materially to mislead and disappoint those inclined to recreate themselves with this interesting subject.
Phenomena of Internal Movements in Diatomaceæ of the North Sea, belonging to the Genera Coscinodiscus, Denticella, and Rhizosolenia
Authors: Schultze Max 
Published: April 2021

ABSTRACT
The sea around Heligoland is rich in large Diatoms, which are frequently brought up in considerable numbers by the fine net. Several of the species very abundant there have been found by Ehrenberg at Cuxhaven, as Coscinodiscus, Zygoceros, Eucampia, Triceratium (‘Abhandl. d. Akad. d. Wiss. z. Berlin’1839). Others are still not known out of that region, as Chætoceros (Brightwell, ‘Quart. Journ. of Micr. Science’ 1856, p. 105, tab. vii), Denticella, Rhizosolenia.
On the Development of Sagitta
Authors: Gegenbaur C. 
Published: April 2021

ABSTRACT
Having in a former volume of this journal given an account of what is known respecting the structure and relations of Sagitta bipunctata, we have thought that an abstract of Dr. Gegenbaur’s observations on the subject of reproduction in that genus would not be unacceptable; and the more so, as this part of the history of Sagitta has hitherto been involved in much obscurity.
On some new and interesting Forms of British Zoophytes
Authors: Hincks T. 
Published: April 2021

ABSTRACT
A New species of Plumularia was characterised under the name of P. similis, closely allied to the P. echinulata of Peach. Two new species of Polyzoa were also described, one as Avenella dilatata, the other, which exhibits a new generic type, as Arachnidia hippothöoides, a delicate ctenostomatous Polyzoon, curiously resembling in general appearance the well-known Hippothoa. Mr. Hincks also drew attention to the remarkable difference in the form of the male and female capsule in Halecinum Beanii and H. halecinum.
On the Reproduction of Nassula Elegans (Ehr.)
Authors: Cohn Ferdinand 
Published: April 2021

ABSTRACT
Although the reproduction of the Infusoria by a motile internal progeny (schwarmsprosslinge) is well established in the case of several species, the number of forms in which the production of endogenous embryos has been observed is so limited, that we are not at present justified in expressing a decided opinion as to the universality of this mode of reproduction, and it remains therefore a matter of interest still to collect new facts respecting it. In the çourse of the last summer I had an opportunity of ascertaining the existence, besides some incompletely observed instances, of a decided, though peculiarly modified case of embryoformation, in the interesting Infusorium described by Ehrenberg as Nassula elegans.
What are Marine Diatoms?
Authors: Walker-Arnott G. A. 
Published: April 2021

ABSTRACT
In the Preface to the late Professor Smith’s second volume of ‘British Diatomaceæ,’ at p. 25, we find—”I feel persuaded that a marine species will not flourish under fluviatile influences, nor a fresh-water form long survive when transferred to a marine habitat. Still further, I believe that certain species are far more special in their tastes, some selecting mountain-torrents, and others fixing their habitation in boggy pools or alpine lakes; some being exclusively littoral, and others found only in the deeper parts of the sea.” As a mere speculation, this statement is of little consequence, but Smith applies it to the determination of species, when other means fail; thereby employing it, not as a theory, but as an ascertained fact.
On the Measurement of the Stride of Diatoms
Authors: Sollitt J. D. 
Published: April 2021

ABSTRACT
A Paper having appeared in the ‘American Journal of Science’ for March, 1859, by W. S. Sullivant and T. G. Wormley, on the “Measurement of the Striæ of Diatoms,” I think it necessary to make a few remarks on their observations, in order to endeavour to prevént the spread of far greater errors on this interesting point than those which, they consider they have corrected. As the subject now stands, it is very similar to the men with the chameleon; and had Messrs. Sullivant and Wormley, béfore publishing their paper, made themselves better acquainted with all the variations in the markings on the Diatomacese, they would have come to a different conclusion to what they have done. To show that this is the fact, I will first call attention to the Pleurosigma fasciola. Of this diatom the kind we find near Hull are very small, and consequently the markings extremely fine, the finest being, as I have Before stated, 90 in the of an inch; but the Fasciola we get from Boston, in Lincolnshire, are many of them so large that there are not more than 50 strise in the 1/1000 th of an inch. I have frequently seen the longitudinal and cross strise at the same, time on the largest-sized Fasciola, from Boston, with the half-inch objective, either of Ross or of Powell and Lealand but the finest we find at Hull will defy even Powell’s one-sixteenth, with 175° of angle of aperture, to show the same, use what illumination you may. The length of the finest Hull Fasciola is under of an inch, whilst some of the Boston Fasciola measure more than of an inch in length. Again, in the P. strigosum, I may observe that those from the coast of Sussex have their markings very strong, even stronger than set down by Messrs. Sullivant and Wormley; but those we find at Hull, and which were first named Strigosum by Mr. Harrison, in 1846, have exceedingly fine markings on them, varying from 72 in the of an inch up to nearly 80. With regard to the strise on the Nitzschia sigmoidea, we have another very striking instance of how little we know respecting the markings on the Diatomacese. I have one slide of this diatom, on some of which the markings are very strong and easily seen, whilst others, in the same slide, set at defiance every method of illumination to bring them out, and I have little hesitation in stating that the striæ on this diatom vary from 65 in the 1/1000 th of an inch up to a degree of fineness which no lenses that we now have will show. I have always found the various kinds of Nitzschia to be the most irregular in the number of their striæ in the inch, of any Diatomaceæ that I have studied.
On the Common Nervous System (Kolonialnervensystem) of the Bryozoa (Polyzoa), exemplified in Serialaria Coutinhii, n. sp
Authors: Muller Fritz 
Published: April 2021

ABSTRACT
In animals living associated in a common colony or stock, movements of the entire growth or of individual animals may often be observed—movements which, though spontaneous, do not appear to depend upon the will of the individual, but to be carried out by them in obedience, as it were, to a command from a higher quarter. This is the case with the Polyzoa. In a species of Pedicellina, in which the cell is supported upon a rigid peduncle, mm. long, affixed by a thicker moveable socket, the motion of the peduncle continues unchanged for a whole day after the removal of the animal itself. In a far smaller species of the same genus, which frequently occurs as a parasite upon other Polyzoa and Hydroida, the peduncles, which are moveable throughout their entire length, begin to move in the most active manner at a time when the animal at the summit is scarcely distinguishable in the form of a bud. I also remember noticing in Mimosella gracilis, Hincks, common and simultaneous movements of the distichously arranged cells. Now, since in these animals, as in other Polyzoa, the existence of nerves has been demonstrated, it may reasonably be supposed that a nervous system exists not only in each Polypide, as the agent of its individual spontaneity, but that a similar system also exists for the performance of the common or associated movements of the polyzoary The demonstration of this nervous system, it is true, will be; excessively difficult in the majority of the Polyzoa; the difficulty of course being increased in proportion with the diminutive size, greater amount of calcareous matter, and consequent want of transparency in the test, and diminished under the opposite conditions. In this respect there cannot perhaps be a more favorable subject than a species of Serialaria, by no means rare in the sea of Santa Catharina, whose polyzoary consists throughout of thin-walled, almost perfectly transparent joints or internodes, an inch or more in length. In this species, in fact, a general or common nervous system is more plainly manifest than I remember elsewhere to have met with, except in the case of the Salpæ.
Note on Dr. Hinrich Nitsche'S Paper on “ Some Interesting Points concerning the Mode of Reproduction of the Bryozoa”
Authors: Hincks Thomas 
Published: April 2021

ABSTRACT
In the following brief communication I propose to offer one or two remarks on the important paper by Nitsche published in the last number of this Journal; in which he criticises some of the views of the eminent Swedish naturalist Smitt respecting _the reproduction of the Polyzoa. I shall confine myself at present to a single point, the theory of the “germ-capsule” (“groddkapsel”) of Smitt. This term has been employed to designate the dark-coloured, more or less circular bodies, which are commonly present in the older cells of the Polyzoan colony, and were long regarded as ova. Smitt claims to have established the very interesting fact that they are in reality produced by the decomposition of the polypides previously in possession of the cells, and that they originate fresh zooids to fill the places of those which have thus disappeared. He describes the “germ-capsule,” as it occurs in several species, and also the evolution from it by budding of a new polypide.
On the Embryology of Limulus Polyphemus
Authors: Packard A. S. 
Published: April 2021

ABSTRACT
The eggs on which the following observations were made were kindly sent me from New Jersey, by Rev. Samuel Lockwood, who has given an account of the mode of spawning, and other habits, in the ‘American Naturalist.’ They were laid on the 16th of May, but it was not until June 3rd that I was able to study them. The eggs measure ‘07 of an inch in diameter, and are green. In the ovary they are of various hues of pink and green just previous to being laid, the smaller ones being, as usual, white. The yolk is dense, homogeneous, and the yolk granules, or cells, are very small, and only in certain specimens, owing to the thickness and opacity of the egg-shell, could they be detected.
The Nature of Connective Tissue
Authors: Krause W. 
Published: April 2021

ABSTRACT
It is usual to distinguish as the fundamental types of connective tissue two modifications, the ordinary fibrous or homogeneous and the reticulated. The former is usually regarded as consisting of a distinctly or indistinctly fibrillated intercellular substance, and variously formed cells, the connective-tissue corpuscles, imbedded therein; and these are described sometimes as stellate, sometimes as spindle-shaped or roundish, sometimes angular and flat. Reticular or areolar connective tissue is composed of anastomosing stellate cells (connective-tissue corpuscles), in the interstices of which is contained fluid with suspended lymph corpuscles.
Review: On the so-called Chorda of the Ascidian larvœ, and the alleged affinity of the invertebrate and vertebrate animals
Authors: Donitz W. 
Published: April 2021

ABSTRACT
Dr. DONITZ has availed himself of a stay in Naples to study the development from the egg of Clavellina lepadiformis. The Berlin zoologist, as a result, comes to the conclusion that Kowalewsky and Kupffer have unfortunately made a very great mistake in pronouncing the development of Ascidians as broadly and generally identical with the development of the vertebrates. He, on the contrary, has been taught by his researches that the development of the Ascidians speaks in a very distinct manner precisely against the affinity of the invertebrates and the vertebrates. One would think that men like Kowalewsky and Kupffer understand something of the developmental history of animals, and especially of the vertebrates. Dr. Donitz, nevertheless, admonishes the former especially, that he makes use of such expressions as keimblatter, chorda, nervous system, &c., in such a way as though a signification, long since firmly established in science, had not been attached thereto. Now, since others are included in this crushing condemnation of Kowalewsky and his work, who have given their adhesion to his researches; and since to these last, such men as Gegenbauer and Haeckel belong, not to mention so many others, we are naturally in a state of anxiety to know what kind of argumentation it is which Dr. Donitz brings into the field.
On the Colouring Matter Of some Aphides
Authors: Sorby H. C. 
Published: April 2021

ABSTRACT
Those who have orchards are no doubt often only too familiar with the red Aphides found in downy patches on the bark of the apple tree. These are coloured by a substance possessing somewhat remarkable properties, connecting it on the one hand with cochineal, and on the other with the hæmoglobin of the blood of vertebrate animals. It rapidly changes into a series of new products, which have remarkable optical characters, and are in some respects analogous to the colouring matters of oils and fats.