bluuebunny/crossref_metadata_2025 huggingface dataset:
Derangement of microtubule arrays in interphase and mitotic PtK2 cells treated with deuterium oxide (heavy water)
Authors: Lamprecht Jan , Schroeter Dieter , Paweletz Neidhard
Published: April 2021

The extent and pattern of the rearrangements of microtubule arrays in interphase and mitotic PtK2 cells treated with deuterium oxide (2H2O) were evaluated using light, immunofluorescence and electron microscopy.

Combined labelling with anti-tubulin antibodies and staining with a DNA-specific fluorochrome revealed that 2H2O influences the reassembly of the cytoplasmic microtubule complex (CMTC) of interphase cells after depolymerization of microtubules (MTs) with nocodazole. In cells entering mitosis in the presence of 75% 2H2O the conversion of the CMTC into the mitotic spindle was affected, resulting in a retardation of the prophase/prometaphase transition. (Pro)metaphase cells did not assemble a regular mitotic spindle and the metaphase/anaphase transition was blocked. Immunofluorescence and ultrastructural studies suggest that separation of centrosomes, nucleation of MTs around centrosomes, organization of MTs into the mitotic spindle, as well as the ultrastructure and positioning of the mitotic poles, are affected in deuterated PtK2 cells. In comparison with control cells, a significantly higher proportion of multipolar divisions was found after stimulation of proliferation in the presence of 25-50% 2H2O or during recovery after a long-term exposure to 75% 2H2O.

On the basis of these results we discuss the mechanism of the antimitotic action of deuterium oxide and suggest that, apart from perturbation of MT polymerization, it could also encompass disturbances in MT reorganization, most probably by impairment of the microtubule-organizing centres (MTOC).
Factors influencing perpendicular elongation of embryonic frog muscle cells in a small applied electric field
Authors: McCaig C. D. , Dover P. J.
Published: April 2021

The mechanism controlling the perpendicular elongation of embryonic muscle cells exposed to a small applied electric field has been studied using a pharmacological approach. Inhibition of the inositol phosphate second messenger system, of calcium entry and of microfilament polymerisation all prevented perpendicular elongation. A model involving strengthened adhesion asymmetrically along the cathodal-facing side of round myoblasts and incorporating the above requirements is proposed to explain electric field-induced perpendicular differentiation.

Some asymmetry of organelles is described also, with ribosomes, yolk granules and actin filaments all predominantly found on the anodal side of myoblasts.
Neural crest cell locomotion induced by antibodies to β1 integrins A tool for studying the roles of substratum molecular avidity and density in migration
Authors: Duband Jean-Loup , Dufour Sylvie , Yamada Susan S. , Yamada Kenneth M. , Thiery Jean Paul
Published: April 2021

Migration of neural crest cells depends on direct, transient interactions between fibronectin molecules and their corresponding Arg-Gly-Asp integrin receptors. We have previously suggested that the moderate-avidity interaction between integrin receptors and fibronectin may be critical for the transient association of the cells with their substratum. In order to test this hypothesis, we have examined the in vitro locomotory behavior of neural crest cells on substrata of differing apparent avidities for integrin receptors. As substrata, we used a variety of monoclonal and polyclonal antibodies to the integrin β subunit that were characterized for their respective relative apparent avidities for the receptor. Neural crest cells were able to migrate on these antibodies and exhibited an organization of substratumadhesion sites and of cytoskeletal elements virtually identical to that observed on fibronectin, indicating that they can at least partially mimic the migrationpromoting activity of fibronectin. However, the number of migrating cells as well as their morphology and their speed of locomotion varied significantly with both the concentration of the antibody substratum and its relative avidity for the receptor. Thus, on high-avidity monoclonal antibodies and on polyclonal divalent antibodies at high concentrations only a limited number of cells escaped from the neural tube, and the rate of their migration was reduced compared to that on fibronectin (23±5/μh−1versus 65±10/μh−1). In addition, cells were unusually flattened and cohesive. Time-lapse videomicroscopy revealed that, on high-avidity substrata, neural crest cells were able to extend cell processes that adhered to the substratum, but showed a dramatically reduced capability of breaking pre-existing substratum contacts. In contrast, the same antibodies at low concentrations produced neural crest cell migration at rates very similar to those on fibronectin at the same concentrations. Low-avidity monoclonal antibodies and polyclonal monovalent antibodies at all concentrations tested permitted extensive migration of neural crest cells, which exhibited the same morphology and locomotory behavior as on fibronectin. These results indicate that both the avidity of receptors for the substratum and the number of receptors bound to the substratum are critical in regulating the locomotory behavior of neural crest cells in vitro, and therefore might help to regulate the directionality of migration and final localization pattern of neural crest cells in vivo.
Localization of soluble and insoluble fractions of hydroxyproline-rich glycoproteins during maize kernel development
Authors: Fritz Sue E. , Hood Kendall R. , Hood Elizabeth E.
Published: April 2021

Monoclonal antibodies have been developed against PC-1 protein, the major hydroxyproline-rich glycoprotein (HRGP) from maize pericarp, and have been used as probes in an indirect alkaline phosphatase antibody assay to localize this protein in tissue of three maize varieties. Kernels were sampled several days after pollination (d.a.p.). HRGPs were assayed by reacting antibodies with tissue prints of kernels and embedded tissue samples. Tissue prints show that soluble HRGPs are present in small quantities even at early stages of kernel development The greatest accumulation of PC-1 in the pericarp is at the top of the kernel. As the kernels mature, HRGPs begin to accumulate in the developing embryo. Total HRGPs in embedded tissue begin to accumulate at 10 d.a.p. and increase quite dramatically at 20-30 d.a.p. Popcorn kernels lose antigenic reactivity at 40 d.a.p., while sweet corn kernels continue to show strong reactivity.
A new direct-viewing chemotaxis chamber
Authors: Zicha Daniel , Dunn Graham A. , Brown Alastair F.
Published: April 2021

A new form of chamber for studying chemotaxis, similar in principle to the Zigmond chamber, allows the behaviour of the cells in a linear concentration gradient to be observed directly. The chamber was developed mainly for studying chemotaxis in fibroblasts using interferometric microscopy and the main design criteria were that it should have better optical characteristics, a higher dimensional precision and better long-term stability than the Zigmond chamber. It is made entirely from glass by grinding a blind circular well centrally in the counting platform of a Helber bacteria counting chamber. This procedure leaves an annular ‘bridge’, approximately 1 mm wide, between the new inner circular well and the original outer annular well. This bridge fulfils the same function as the linear bridge of the Zigmond chamber but the preciseconstruction of the counting chamber ensures that a gap of 20/nn between bridge and coverslip can be accurately and repeatedly achieved when the chamber is assembled. It is envisaged that the improved optical clarity, dimensional accuracy and long-term stability of the new chamber will be advantageous in other applications, particularly in studies requiring critical microscopy or a precise knowledge of the gradient and in studies of cells, such as fibroblasts, that move much more slowly than neutrophils.
Isolation and ultrastructural analysis of microfibrillar structures from foetal bovine elastic tissues: Relative abundance and supramolecular architecture of type VI collagen assemblies and fibrillin
Authors: Kielty Cay M. , Cummings Christine , Whittaker Stephen P. , Worth C. Adrian Shuttle , Grant Michael E.
Published: April 2021

Extensive intact assemblies of matrix macromolecules have been solubilized from foetal calf skin, nuchal ligament and aorta by a new procedure that includes bacterial collagenase digestion under nonreducing, non-denaturing conditions and gel filtration chromatography. Type VI collagen was identified as the major microfibrillar element of these tissues by SDS-PAGE analysis and Western blotting. Rotary shadowing electron microscopy of these preparations revealed by far the most abundant and extensive arrays of intact collagen VI microfibrils isolated to date. The distinct microfibrillar species, fibrillin, which was identified on the basis of its periodicity and morphology, was also solubilized in abundance by this protocol. Analysis of these complex polymers has generated new information on their supramolecular architecture and relative abundance in these tissues. The protocol also demonstrates that the release of intact collagen VI microfibrils from these tissues is largely dependent on the removal of the major collagen fibrils.
On Unicellular Plants and Animals
Authors: Siebold C. Th. v.
Published: April 2021

Respecting the motions, which have been frequently noticed in unicellular Algæ, Nägeli observes very truly (p. 19), that they present nothing of a spontaneous or animal character, since they arise, not in the contraction or expansion of the membrane, excited by an external or internal irritant, but proceed singly from the vegetative processes of absorption and excretion of fluid, and the formation and solution of solid matters. Of the four categories of these plant-motions distinguished by Nägeli, we are here interested only in the third and fourth, since it is precisely those which have been confounded with animal movements.
Die Pelanzenzelle, Der Innere Bau Und Das Leben Der Gewachse, &c.
Authors: Schacht Hermann
Published: April 2021

This work, for which the author has recently received a decoration from the King of Prussia, was briefly alluded to in a former part, and we here take occasion to lay a somewhat extended account of it before our readers. Dr. Schacht’s book is one that has attracted great notice, and will have considerable influence on the progress of the microscopic examination of vegetable structure, but this will not be so much the result of originality of the matter contained in it as of the method pursued in the investigations and in the exposition of them. In fact there are few new points, and the merits of the work rest chiefly upon the industry and directness with which the author has worked over the whole field of vegetable anatomy under the point of view laid down in his title, that of comparison of the tissues in the various classes, not merely by simple inspection, but by parallel series of observations on development, assisted by the systematic application of reagents for the determination of the chemical characters. The mode of operation pursued is thus described in the Introduction (p. 7).
Translations
Authors: Braun Alex
Published: April 2021

Algarum Unicellularium Genera nova et minus cognita, præmissis Observationibus de Algis Unicellularibus in genere.
Modes of determining, by the use of the microscope, the refractive index of fluids.
Authors: Robertson William
Published: April 2021

A knowledge of the laws which the rays of light observe in their course through refracting media enables us, with the help of the microscope, to determine the index of refraction of certain substances, to which, on account either of their small quantity or of their insufficient transparency except when in layers of extreme thinness, the ordinary methods are inapplicable.
On Stephanosphæra Pluvialis
Authors: Currey Frederick
Published: April 2021

Stephanosphæra pluvialis was first observed by Cohn, in 1850, near Hirschberg, and described in Siebold and Kölliker’s ‘Zeitschrift’* vol. iv, part 1. It consists of a hyaline globe, containing eight green primordial cells, arranged in a circle in its equator. The globe rotates upon an axis perpendicular to the plane in which the primordial cells are arranged, and moves actively in space by the aid of cilia, two of which proceed from each of the primordial cells, and pierce the hyaline envelope.
Further Observations on the Genera Triceratium and Chætoceros
Authors: Brightwell T.
Published: April 2021

My former papers on these Genera have been chiefly confined to the description of species, and are necessarily imperfect, and to that extent unsatisfactory, in consequence of the difficulty of obtaining specimens in a living state. The species being all marine, very few opportunities occur of seeing them alive, and it is doubtful whether any one of them has been seen in a state of conjugation. If, as one of our highest authorities (the late lamented author of the ‘Synopsis of the British Diatomaceæ’) says, “neither size nor outline can be wholly relied on, and striation is the best guide for specifie character and, when this fails, the arrangement of the endochrome, or the habitat of the living frustule,” it is obvious how few of the described species can have been sufficiently known to warrant us in deeming them finally established, and how important is every step towards attaining a knowledge of the living diatom, and especially of its modes of increase.
On some peculiarities in the Microscopical Structure of Crystals, applicable to the determination of the Aqueous or Igneous Origin of Minerals and Rocks
Authors: Sorby H. C.
Published: April 2021

In this paper the author showed that when artificial crystals are examined with the microscope, it is seen that they have often caught up and inclosed within their solid substance portions of the material surrounding them at the time when they were being formed. Thus, if they are produced by sublimation, small portions of air or vapour are caught up, so as to form apparently empty cavities; or, if they are deposited from solution in water, small quantities of water are inclosed, So as to form fluid-cavities. In a similar manner, if crystals are formed from a state of igneous fusion, crystallizing out from a fused-stone solvent, portions of this fused stone become entangled, which, on cooling, remain in a glassy condition, or become stony, so as to produce what may be called glass- or stone-cavities. All these kinds of cavities can readily be seen with suitable magnifying powers, and distinguished from each other by various definite peculiarities.
On Apparatus for Dredging at Moderate Depths in the Deep Sea, and for Capturing Floating Objects from Shipboard
Authors: Wallich G. C.
Published: April 2021

During a recent voyage from India, the success attending the use of certain appliances contrived by me for capturing such marine objects as came in our way, induces me to offer the subjoined account of them to the public. I may mention that, although familiar with the ordinary form of towing net and sounding apparatus, it struck me that much more might be done by resorting to some simple form of casting net, than is possible where the chapter of accidents is relied on for bringing within the jaws of the towing net the objects required, and by constructing some more portable sounding apparatus, which would at the same time prove effective at moderate depths, and bring up a much larger quantity of material than is attainable under the ordinary sounding lead, or the more complicated and cumbrous contrivance of Lieutenant Maury and others. I would further premise that whoever desires to make a collection of marine floating molluscs, tunicaries, ascidians, and the like, and also the minuter organisms which exist in all latitudes in the open ocean, to a greater or lesser extent, will be grievously disappointed if he imagines that the trailing net used astern of a ship will suffice for the purpose. For, to be at all successful, constant and unremitting watchfulness is, in the first place, essential ; and what is equally important, a fitting place of observation at the stern of the vessel, with ten or twelve feet of the water bend. In my own case, the quarter gallery of a 1500-ton merchantman afforded the best of all look-out ports ; and from it I was enabled to use the casting net about to be described with ease and certainty. In the clear blue water of the open sea it is astonishing how rapidly the eye accustoms itself to detect creatures of the minutest size ; and how readily it learns to distinguish, even in the small patches of calm water between each wave when a considerable sea is running, any object that may chance to be swimming near the surface. Nor is this confined to the portion of sea immediately below the observer, but it can be done at a distance of several yards. In order to embrace this distance the following casting net was constructed, and in the course of a short practice it became easy to pitch this net, quoit fashion, over any object within such range.
On the Recent Foraminifera of Great Britain
Authors: Williamson William Crauford
Published: April 2021

The publication of Professor Williamson’s work is a triumph for the microscope that we must not pass over without notice. This beautiful volume, which has been published by the Ray Society presents for the first time, to the British naturalist a full account of the living Foraminifera found on our coasts. It embraces a very accurate description of each species, with a delineation by Tuffen West. The only complaint we could possibly make about the book is that the Ray Society has chosen to publish it in a quarto form, when it would have been so much more convenient as an octavo, or even duodecimo. In these days of locomotion, when we pack our microscopes into the smallest possible space, we also want our books small, if they are to travel with us. It was all very well for our forefathers to publish quartos and folios, for they had leisure to admire the grandeur of their tomes; but we have the greatest difficulty in keeping up with our day, and everything that spares time must be accepted as a boon.
Descriptions of diatomaceæ Observed in californian guano
Authors: Greville R. K.
Published: April 2021

It is well known that in studying Diatomaceæ as they occur in guano and in deposits, the observer labours under great disadvantages. The materials he has to work upon are often scanty, and forms which attract his attention are sometimes so scarce that he is obliged to review with the utmost care a multitude of preparations before he can arrive at a satisfactory conclusion regarding them. The conditions so well laid down by Professor Smith, as requisite for the determination of species, are in such cases, to a considerable extent, beyond his reach. It has consequently been a question whether any Diatom ought to be described except from recent, and, in some genera, actually living individuals. Undoubtedly it would be always desirable to conform to such a rule when practicable; but so many justifiable exceptions present themselves, that it can never be enforced as a positive law. The best writers on this most interesting order, even Professor Smith himself, occasionally deviate from it. Witness his description of Himantidium (?) William- sonii, made from specimens insufficient to determine even the genus; for he had only the front view of the frustules- before him. Professor Gregory supplied the deficiency by figuring the side view, and still the genus is not settled. Nevertheless, it was unquestionably desirable that we should possess good representations of so very curious a production. Were we rigidly to confine ourselves to those species only, whose history as living vegetables we have the means of tracing, many of the most curious and beautiful forms on record—even entire genera—would have to be expunged from our books; such, for example as Heliopelta, Asteromphalus, Asterolampra, &c. The truth is, that while many frustules occurring in deposits require to be described—if described at all—with extreme caution, numerous others, especially of disciform genera, exhibit at least sufficiently marked distinctive characters. All that can be said, I apprehend, against the description; of such diatoms is that from the very nature of the case we are unacquainted with their history. Something, nevertheless, it must be admitted, is gained by the publication of accurate figures; for even if they fail in some cases to establish species, they will at least assist to indicate the range of variation, a point in itself of no small importance.
On the Measurement of the Vertical Thickness of Microscopic Objects; and on the Determination of the Chemical properties from their Refractive Power
Authors: Welcker H.
Published: April 2021

In the ‘Zeitschrift f. Rat. Medicin,’ N. F., vi, p. 172, and viii, p. 241, the author endeavoured to show, that when by a methodical raising or depression of the tube of the microscope the relief of microscopic objects has been ascertained,—the question, especially as respects the more difficult class of objects, may be decided, as to whether they are hollow or solid, depressed or convex. If a microscopic object be of such a size as to allow of its near and distant surfaces being each distinctly and separately brought into view by the proper adjustment of the tube of the instrument, the determination of this question is usually unattended with any difficulty; the proceeding, in fact, being one commonly practised. The author, however, has endeavoured to show, that in the smaller or even in the most minute microscopic formations—so small even that they appear only as simple dark points—a bright flash or gleam ensues upon the elevation of the tube, in those cases that is to say in which the bodies in question are convex; and a similar flash on the depression of the tube, when they are concave. “I have shown,” he says, “that in the former case the convex corpuscles act like minute convex lenses, and in the latter like concave lenses. Oil-drops contained in water or air, albuminous and many other sorts of particles,—in short, all such as in regard to their optical property are referable to the perfectly spheroidal form, show the brilliant appearance on the elevation of the tube; whilst minute air-bubbles, the cavities in bone, teeth, &c., containing air or fluid, &c., present the same phenomenon when the tube is lowered.
Microscopical society, March 30th, 1859
Authors: Lankester Dr.
Published: April 2021

F. E. Webb, Esq., J. O. Dix, Esq., and Joseph Beck, Esq., were balloted for, and duly elected members of the Society.
On the Markings of Diatomaceæ
Authors: Rylands Thos. G.
Published: April 2021

It is not easy to over-estimate the importance of the department “Notes and Correspondence” in your Journal. Not only does it afford a means of recording facts which might otherwise remain unpublished; but the various hints and memoranda contained in it possess a value to the country student which those only who are similarly situated can appreciate. The note by Dr. Greville, “On a Structure observed in Surirella,’ vol. vii, p. 116, recalled my attention to the subject of the present article, and reminded me that on two occasions I had observed something similar in naviculoid frustules. The first was in Pleurosigma balticum, where the internal marking was hexagonal; and the second in a frustule of Amphipleura pellucida, where there were transverse lines, but much more distant than the 130 to 001” observed in that species by the Hull microscopists. Ill neither of these instances were the slides my own, and they were not seen under circumstances which enabled me to do more than record the fact of their occurrence. In neither case was the idea of a septum entertained; the internal markings had distinctly the curve of the side of the frustule, and the impression conveyed was simply that both surfaces of the silica were marked. I had the less hesitation in coming to this conclusion, from having frequently seen something similar, but apparently constant, in certain disciform species. The fact that certain species of Actinocyclus, &c., have two very evident sets of markings is generally known. It is hardly less probable that the same thing has been seen in Coscinodiscus centralis, and that the fine secondary markings of Triceratium favus (indicated by Dr. Wallich in what he calls T. fimbriatum) have been observed by those who have directed their attention to that species.*
Some Observations on the Structure of Nerve-fibres
Authors: Lister Joseph , Turner William
Published: April 2021

Having recently had the opportunity, through the kindness of Mr. Lockhart Clarke, of inspecting some of his beautiful preparations of the spinal cord, we were struck -with an appearance which had not yet received a satisfactory interpretation ; and, having been induced to investigate the point, we have met with some facts which seem of sufficient interest for publication.
Supplementary Observations
Authors: Lister Mr.
Published: April 2021

The fibroid arrangement of the white substance of Schwann in nerves hardened by chromic acid has been minutely described by Stilling, in his elaborate treatise on the ‘Nervefibre and Nerve-cell,’ * a work which we had not seen when the foregoing communication was written, but a copy of which was kindly lent me by Professor Goodsir, soon after Mr. Turner had left Edinburgh for the vacation. According to Stilling, the medullary sheath is, even in perfectly fresh nerves, composed of a network of fibres, which are continuous with others in the axial cylinder and in the proper investing membrane; so that, in his opinion, these three constituents of the nerve-fibre differ from each other only in the manner in which their elements are disposed * This view is not only quite novel anatomically, but is opposed to the generally received physiological opinion, that the axial cylinder is the essential part of the nerve-fibre, and the medullary sheath an insulating investment. Considering the high estimation in which the writings of Stilling on the anatomy of the nervous centres are deservedly held, and the influence which therefore attaches to his opinions, it seems fortunate that we have been able to present so clear a demonstration that the axial cylinder is chemically as well as morphologically totally distinct from the medullary sheath.
On American Diatomaceæ
Authors: Edwards Arthur M.
Published: April 2021

A taper of mine, on American Diatomaceæ, was read before the London Microscopical Society, March 30th, 1859, and published iu their Transactions, in which an omission occurred which I herein wish to rectify. A mistake occurred in re-writing, so that the description of the species found at Charleston harbour, S. C., was left out. A paper on this subject, by the present writer, was read before the New York Lyceum of Natural History, February 21st, 1859, a copy of which is annexed:—
Memoir on the Spermogones and Pycnides of Filamentous, Fruticulose, and Foliaceous Lichens
Authors: Lindsay W. Lauder
Published: April 2021

This very able and laborious memoir was published in the ‘Transactions’ of the Royal Society of Edinburgh, and we call the attention of our readers to it, as affording by far the most exhaustive account yet published of the minute structure of the lichens. Dr. Lindsay, in his papers in this Journal, on the genus Abrothallus, and on the structure of Lecidea lugubris (vol. v), commenced that line of investigation, which he has carried out in this memoir to a large section of the whole family of lichens. In his introduction, the author draws attention to some of the difficulties which impede the progress of the inquirer in the path he has chosen for investigation.
On Some Freshwater Rhizopoda, New or Little-Known
Authors: Archer William
Published: April 2021

Having endeavoured in the foregoing to give some account of the remarkable form, Diaphoropodon mobile, I pass on to the three others, which in the present series seem next related thereto, figured on Pl. XX, figs. 1, 2, 3 (vol. ix), and which I would (provisionally at least) identify as above. I regret, however, that I have it in my power, at present at least, to do but very little more than refer to the figures and the accompanying explanation of the plate.
On the Embryonic Form of Nematobothrium Filarina, Van Ben
Authors: Van Beneden Edouard
Published: April 2021

In his memoir on the Intestinal Worms, M. P. J. Van Beneden made known an extremely remarkable animal which he described under the name of Nematobothrium filarina.1 It lives parasitically in Sciæna aquila, a fish which is found sometimes on our coasts and which is met with from time to time in the Channel and on the coasts of the Atlantic. But as it is always a relatively rare fish, one has not at all times the opportunity of studying the singular parasites which this animal harbours.
On the Minute Anatomy of some of the Parts concerned in the Functions of Accommodation to Distance, with Physiological Notes
Authors: Macdonald John Denis
Published: April 2021

No organ in the body exhibits more beauty of construction to unravel, or more interesting physiological problems to solve, than the eye; and it is no wonder, notwithstanding the great advances of modern science, that much room should still remain for the improvement of our knowledge of its minute anatomy, and the function subserved by every part in the economy of vision. It would be quite impossible within the limits of a few pages to deal with a twentieth part of the facts and views that have been advanced from time to time in relation to the subject of the present paper. Nor would that be the writer’s intention, though it were possible, being merely desirous of making known some few anatomical particulars which do not appear to have been hitherto noticed, and of associating these with the function of accommodation to distance.
On the Best Methods of Studying Transparent Vascular Tissues in Living Animals
Authors: Caton Richard
Published: April 2021

During the last three years, the researches of Professor Cohnheim and other German observers have rendered the study of the relation between vessels and parenchyma particularly interesting to physiologists.
On an Aplanatic Searcher, and its Effects in Improving High-Power Definition in the Microscope
Authors: Royston-Pigott G. W.
Published: April 2021

The Aplanatic Searcher is intended to improve the penetration, amplify magnifying power, intensify* definition, and raise the objective somewhat further from its dangerous proximity to the delicate covering-glass indispensable to the observation of objects under very high powers.
Researches on the Composition and the Significance of the Egg, based on the Study of its Mode of Formation, and of the first Embryonic Phenomena—(Mammifers, Birds, Crustacea, Worms)
Authors: van Beneden Edouard
Published: April 2021

The very valuable Memoir of Dr. Van Beneden is at length published, consisting of nearly 280 pages quarto, and twelve excellent plates. It is impossible for us here to give an adequate sketch of so extensive and valuable a work. The numerous details and observations which it contains are, however, all directed to establish certain conclusions concerning the signification of the egg, and the various parts which compose it, which we shall state, referring the reader with great confidence to the clear, logical, and interesting details of observation given in the Memoir. It was not,” remarks Dr. Van Beneden, “until after the appearance of the memorable works of Von Baer, Purkinje, R. Wagner, Coste, Prevost, Dumas, and Rusconi on the Vertebrata, of Rathke, Hérold, von Siebold, and P. J. Van Beneden on the lower animals, that the bases of comparative ovology and embryogeny were definitely established. The constitution of the egg of the superior animals, and of a certain number of inferior animals, was known, and it was perceived that throughout the egg consists of the same essential parts: of a membrane, of a vitellus, and of a germinal vesicle, holding in suspension one or several refringent corpuscles. On the other hand, the breaking up or cleavage which Prevost and Dumas had established in the Batrachia came to be discovered in Fishes by Rusconi and Von Baer; Von Siebold pointed it out in certain Nematods; Dumortier, Van Beneden, and Windischman in some Gasteropods.
On some New Species of the Genus Amphiprora
Authors: O’Meara Eugene
Published: April 2021

Some of the Diatoms which are the subject of this paper have been brought under notice from time to time at our club meetings. And now I desire to present them in regular form, adding such species as have come under my observation in the interval. The material which furnished them was collected by our respected club member, Dr. E. Perceval Wright, during his sojourn in the Seychelles. This very active member of our circle has contributed largely to the interest of our meetings, and to the value of our ‘Proceedings,’ by various communications in his own speciality, arising out of his researches in that hitherto unexplored district, and has placed me under a debt of gratitude for the material with which he has supplied me, containing in abundance diatomaceous forms of the greatest beauty and rarity.
Microscopic Objects, Figured and Described
Authors: Martin John H.
Published: April 2021

This work contains 194 tolerably executed figures of what are sometimes called “natural history objects,” among which we find, for instance, the “pollen of the evening primrose/’ “a skin parasite from the human nose,” and “marble from the Temple of Diana, at Ephesus;” represented under various degrees of magnifying power, and some without any enlargement at all. The figures are accompanied by short descriptions and a few hints as to preparation. When we say that the specimens selected are almost unclassified, and that the author does not claim to establish, by his delineations, any facts unknown before, or to contribute anything to the settlement of disputed points, the character of his book will, we think, be evident. It does not fall specially under the head of any one of the sciences which the microscope is used to illustrate, but rather appeals to those who are on the look-out for objects to use their microscope upon. It is obviously the work of a zealous and experienced field naturalist, who has brought together his materials from very various sources, and takes genuine delight in the beauty and strangeness of the forms which display themselves before him.
Notes And Memoranda
Authors: Kühne Wilhelm
Published: April 2021

Professor of Physiology at Amsterdam, well known for his researches in histology as well as in physiological chemistry, has been appointed Professor of Physiology in the University of Heidelberg, as the successor of Professor Helmholtz, who has been called to a similar post at Berlin
On The Production of Spores in the Radiolaria
Authors: Cienkowski L.
Published: April 2021

Almost all that we know of the developmental history of the Radiolarians renders it extremely probable that the Capsule takes an important part in the reproduction of these organisms. Besides the oft observed multiplication of the Capsule by division, science possesses some other evidence which seems to be of great importance. Joh. Müller1 saw in the interior of an Acanthometra a swarming of small monad-like vesicles, which moved about for a time, and then changed themselves into Actinophrys-like structures. Since the subsequent history of these monad-like bodies was not made out, the suspicion of the intrusion of some parasitic organism could not in this case be set aside.
Notes on the Genus Doliolum
Authors: Moss Edward L.
Published: April 2021

There can be but little doubt that the distribution of ocean surface life is considerably influenced by the great systems of oceanic circulation which recent researches have disclosed. Such circulation probably tends to assimilate the inhabitants of adjacent ocean basins, and helps to explain the remarkable similarity in the faunas of even widely separated seas. But unless surface animals can live with equal facility at considerable depths, a sort of retentive selection will be exerted on those that drift in through narrow straits into seas like the Mediterranean, where the surface waters have an average inward flow, and where the denser outward current is in depths removed from the direct influence of light and air.
On “Molecular Coalescence,” and on the Influence Exercised by Colloids Upon the Forms of Inorganic Matter
Authors: Ord W. M.
Published: April 2021

Those who are acquainted with Mr. Rainey’s researches will not find a great deal of new matter in the preliminary communication by Professor Harting, of Utrecht, on the “Artificial Production of some of the Principal Organic Calcareous Formations,” which appeared in last quarter’s number of this Journal.
The Luminous Organs and the Light of the Pholades
Authors: Pancert Paul
Published: April 2021

In continuation of the studies already made on luminous animals, I now present to the academy a work on pholades, concerning particularly the most ordinary species of our seas, namely, the Pholas dactylus L. The phosphorescent properties of these molluscs has been for some time known, and the luminous clouds which they spread in water when touched or moved. Pliny describes this phenomena in a special paragraph of his ninth book.1 His observations were afterwards confirmed by many authors, and Reaumur also wrote on this matter,2 expressing the belief that the outer surface of the pholad creates this luminous matter, illuminating the object it touches, and the water in which one washes one’s hands. According to Reaumur this same matter if dried shines again when wet. Monti, Beccari, and Galeati, as also their contemporary, Reaumur, were much occupied on the subject, and made observations which scarcely differ one from another. They maintain that pholades shine most when in milk. The authors whom I cite in my memoir confine themselves to describing the phenomenon without indicating its precise situation.
On the Protozoon Ophryodendron Abietinum, Claparède and Lachmann
Authors: Hincks Thomas
Published: April 2021

The very curious and interesting Protozoon which is the subject of the present paper was first characterised by Claparède and Lachmann in 1855, and placed by them amongst the suctorial Infusoria, in the group of the Acinetina.1 It was subsequently obtained by Dr. Strethill Wright in Scotland, and described by him under the name of Corethria Sertulariæ. 2 At a later date he published a further account of it, and gave some interesting particulars respecting its reproduction.3 I am not aware that any other naturalist has made it the subject of special investigation.
The Luminous Organs and Light of Pyrosoma
Authors: Panceri Paul
Published: April 2021

The memoir presented by me to the Academy1 is intended to make known the results of the researches which I undertook during last winter, and which I continued in December and January of this year on Pyrosoma giganteum, in continuation of those which I have already made on animal light. In the historical sketch which forms the introduction to my memoir I have quoted, first, the observations made by Peron in the Atlantic between 19° and 20° W. long, (from Paris) and 3° and 4° N. lat., when, in December of the year 1800, on his way to Australia, he met a bank of Pyrosoma, which, during a dark night, strongly illuminated the waves tossed by the storm.
On Cell Theories
Authors: Cleland John
Published: April 2021

Stricker’s article on “The General Characters of Cells,” in his ‘Human and Comparative Histology.’ Published 1868 ; translated by Power 1870.
On the lymphatics and parenchyma of the thyroid gland of the dog.
Authors: Baber E. Cresswell
Published: April 2021

THE following is a concise account of a research carried out under the direction of Dr. Klein, and described at length in a paper read before the Royal Society in January, 1876.2
Contributions to the minute anatomy of the omentum.
Authors: Klein E.
Published: April 2021

I PROPOSE to describe in this short memoir (1) certain bud-like structures occurring on the fenestrated portion of the omentum of rat and dog; (2) the way in which the fenestræ are produced in the omentum of rodents and carnivorous animals ; and (3) some points referring to the new formation of blood-vessels in the omentum of guinea-pig.
On the protrusion of protoplasmic filaments from the glandular hairs on the leaves of the common teasel (Dipsacus sjlvestris).
Authors: Darwin Francis
Published: April 2021

The connate leaves of the common teasel (Dipsacus sylvestris) form, as is well known, cup-like receptacles surrounding the stem of the plant. In the rain-water accumulating in these cups numerous insects are drowned, and their dead bodies convert the water in which they lie into a strongly animalised fluid.
Notes on the structure of several forms of land planarians, with a description of two new genera and several new species, and a list of all species at present known.
Authors: Moseley H. N.
Published: April 2021

Having made a special study of the structure of the Land Planarians of Ceylon, the results of which were published in the ‘Phil. Trans. R. Soc.’ of 1874,1 I was naturally led to extend my observations of the group during the voyage of H.M.S. ‘ Challenger. ’ I collected specimens wherever the opportunity offered, and made such observations on them as my other work permitted. The present paper contains the results of these observations, which are very far from complete, since I have not yet been able to make an extended investigation of all the specimens which I preserved for that purpose.
Motility of the Spermatozoids of Limulus
Authors: Lankester E. Ray
Published: April 2021

Through the kindness of Mr. Carrington E.L.S. of the Westminster Aquarium, I received some months since a specimen of the American King crab in the living condition. My principal object was to study the colouring matter of the blood. Concerning it I will here only remark, that the blood when first shed is almost colourless having but a faint opalescence of a blueish tint. This however, rapidly gives way to a blue colour which increases in intensity for three hours after the blood has been shed, and finally attains a deep indigo tint. The colour is due either to the chemical change, or to the solution of, a substance contained in the corpuscles. The specimen from which I collected the blood was fortunately a male, and was in the full vigour of the breeding season. A quantity of white cream-like sperm was discharged by the animal from the orifices of the seminal ducts, placed on the protected surface of the opercular plate. I was thus able to examine some of the spermatozoa in the mature and living condition. The simple fact which I wish now to record and which I believe has not been previously recorded is, that the spermatozoa of Limulus are actively motile. They are, like the other histological elements of that animal, of very large size. Each presents a lemon-shaped head provided with a delicate tail of great length. At the moment of writing I am unable to lay my hand on the measurements. The vibratile character of the tail is, however, the important matter. Thousands of the spermatozoids were seen swarming together on the field of the microscope, whilst the travelling of isolated individuals over considerable distances was watched.
On the Brain of the Cockroach, Blatta Orientalis
Authors: Newton E. T.
Published: April 2021

The common cockroach, Blatta orientalis, has been found a very convenient insect to take as a type of its order, both on account of its generalised structure, and the readiness with which it may be obtained, in any numbers, at all seasons of the year ; consequently it has been dissected largely in our biological schools.
On the Development Of Synapta Inhær(sp.)
Authors: Thomson Wyville
Published: April 2021

I have had an opportunity during the past summer, through the kindness of my friend Captain Wethered, of observing with care some of the earlier stages in the development of Holothuria inhœrens of O. F. Miiller, so well known to microscopists from the remarkable character of its calcareous armature. This singular Holothurid is abundant, buried in mud banks, at, and a little above, low water mark on the shores of Belfast and Strangford Loughs. I had long been most anxious to trace its mode of reproduction, but every attempt, whether by sifting the surface of the water with a towing net for a swimming larva, or by examining the plants growing on the banks for an early creeping stage, signally failed. In the mean time, Captain Wethered contrived thoroughly to domesticate three or four mature Synaptæ in a small tank; and after they had been upwards of a year in confinement, he was rewarded for his care and patience by a brood of young. He was absent from home for some days in the beginning of June of the year 1861, and, on his return, he detected several extremely minute transparent bodies moving on the surface of the glass of the Synapta tank. On examining these with the microscope he found that they were young Echinoderms, and, even at this early stage, their mode of using their rudimentary tentacles was so characteristic as to leave but little doubt of their parentage. Captain Wethered kindly placed these embryos at my disposal, and I examined them carefully from time to time. There still, unfortunately, remains a doubt, whether there may not be a still earlier condition of swimming larva. The embryo, however, when first observed, was extremely minute (‘8 mm. in length); its structure was very rudimentary, and even in the simplest and most minute embryos there was not the slightest trace of larval appendages. I am, therefore, inclined to believe, that no independently organised pseudembryo is produced, but that the Echinoderm is developed at once from a simple ciliated germ. I shall not, however, consider my task completed, till this point be fairly cleared up; and, in the mean time, I merely offer the present communication as a contribution to the history of a limited period in the development of the young.
Experiments on the Migrations of Entozoa
Authors: Pouchet MM. A. , Verrier
Published: April 2021

In a work published by one of us in 1859, a close comparative examination was made of the doctrines of those observers, who in Germany and Belgium had occupied themselves with the subject of the metamorphoses of the Entozoa and their peregrination through the living organism. The obvious result of this examination was to excite very weighty doubts in every thoughtful mind. M. Davaine, in his remarkable ‘Traité des Entozoaires,’ also says that the conclusion in his mind, from the agreement in the facts and the divergence in the opinions of the experimenters, was “that the question still demands sound criticism and fresh researches.”
On the Structure of the Nephridia of the Medicinal Leech
Authors: Bourne A. G.
Published: April 2021

The Leech’s nephridium consists of gland and vesicle connected by the vesicle duct. The gland is a curved, horse-shoe shaped loop, presenting the following lobes :—1, main lobe; 2, apical lobe; 3, testis lobe; 4, recurrent lobe. The cells which constitute the gland are all penetrated by ductules, which pass through them, sometimes forming several passages; the ductules differ in the different lobes of the gland. The axis of all the lobes is occupied by a large duct separated from the nephridial cells by a thick cuticle ; it opens into the vesicle duct, but is not shown to have any connection with the ductules. Vessels of the hæmal system (with red fluid) form a complete plexus in the gland, each cell being surrounded by a loop of the plexus. There is no internal opening of the system of ducts or ductules. There are no cilia in any part of the gland excepting the vesicle, which is lined by a ciliated epithelium. The wall of the vesicle is muscular; that of the gland is not, but consists of a fibrous, pigmented investment.