bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence that cryptomonad chloroplasts evolved from photosynthetic eukaryotic endosymbionts
Authors: Mcfadden Geoffrey Ian
Published: April 2021

Unicellular algae of the division Cryptophyta possess an unusual subcellular compartment of unknown derivation. This compartment, which is partitioned off from the main cytoplasm by two membranes, contains a chloroplast and a small nucleus-like organelle surrounded by ribosomelike particles. Electron-microscopic in situ hybridization has been used to show that the ribosomes in this subcellular compartment are eukaryotic. In addition, eukaryotic rRNA has been localised within the nucleus-like organelle, suggesting that the rRNAs may be transcribed from genes in this nucleus. This identification of a second, nucleuscontaining eukaryotic compartment within these cells supports the hypothesis that cryptomonads contain a reduced photosynthetic eukaryotic endosymbiont.
Cellulose synthesizing complexes in some giant marine algae
Authors: Itoh Takao
Published: April 2021

The structure of putative cellulose synthesizing complexes (TCs) has been studied in giant marine algae and is discussed in relation to the assembly of cellulose microfibrils. Including previous work, 14 species belonging to nine genera in the Siphonocladales and two species in the Cladophorales are known to have linear TCs on both E- and P-fracture faces of the plasma membrane. Species studied in the present paper included Boodlea composita, Dictyosphaeria cavernosa, Ernodesmis verticillata, Siphonocladus tropicus, Struvea elegans, Valoniopsis pachynema and Chaetomorpha aerea. Contrary to their fairly consistent width (30–36 nm), TCs have a wide distribution of length among indIvidual species and at various stages of development in the same species. Most of the TCs have a random arrangement of subunits, but sometimes they are arranged in three rows. The mean TC length is greater during secondary wall synthesis than in primary wall synthesis in all of the following species: Boodlea composita, Dictyosphaeria cavernosa, Siphonocladus tropicus, Valonia macrophysa, Valonia ventricosa and Chaetomorpha aerea. These results support previous results suggesting that the linear TCs increase their length during cell wall development. The size of TC subunits, ranging from 7.3 to 8.9 nm, was smaller than the structural membrane particles on the plasma membrane in all of the species examined. It is suggested that the spacing between individual glucan chains will be reduced to half after crystallization of cellulose microfibrils, on the basis of evidence that the width of microfibrils is as wide as that of TC. The width of microfibrils ranged from 11.2 to 23.6 nm, while most of the species had microfibrils with a width in the range 14 to 16 nm. The width of microfibrils in Boergesenia was the largest among the giant marine algae. The formation of TCs from subunits, which are transmembrane particles, is characteristic of Siphonocladales in spite of their varying cell morphology.
Cells of the cellular immune and hemopoietic system of the mouse lack lamins A/C: distinction Versus other somatic cells
Authors: Rober Ruth-Ariane , Sauter Auhelmut , Weber Klaus , Osborn Mary
Published: April 2021

Almost all somatic cells in adult murine tissues express all three nuclear lamins (A, B, C). Here we demonstrate that cells of the hemopoietic system of the adult mouse are an exception in that they express only lamin B. Thus T and B lymphocytes as well as granulocytes and monocytic cells directly isolated from spleen, thymus, blood or bone marrow do not express lamin A/C but only lamin B. In agreement with this observation the murine hemopoietic cell lines EL4, BW5147, HK22, 70Z/3, SP2/0 and PAI express only lamin B. In immunoblotting experiments used to confirm the immunofluorescence data no lamin A/C expression was detected.

However, we noticed that murine lamin B occurs in two isoforms, which can be distinguished immunologically. These results reinforce the idea that a functional nuclear lamina can be formed from lamin B alone. They also pose the question of whether cells lacking lamin A/C are more plastic in their developmental programs than those that express all three lamins.
Molecular traffic through plasma membrane disruptions of cells in vivo
Authors: McNeil Paul L. , Ito Susumu
Published: April 2021

We have recently shown that mechanical forces, experimentally imposed or physiologically generated, transiently disrupt or wound the plasma membranes of epithelial cells of the gut and that cultured endothelial cells similarly wounded mechanically at their plasma membranes release a potent basic fibroblast growth factor-like molecule. Here we show that mechanical forces generated by experimental manipulation (tape stripping and needle puncture), or by animal locomotion, transiently wound the plasma membranes of various cells of skin, allowing otherwise impermeant tracer molecules to enter and become trapped within cell cytoplasm. We estimate that the epidermis of digits from actively locomoting animals is composed of 10.5% (±4.9% S.D.) wounded cells, and that from quiescent animals has 3.7% (±2.5%) wounded cells. Wounded fibroblast, glandular and endothelial cells were also identified in mechanically stressed skin. Cells retaining fluorescein dextran, used as a label for wounding, were observed 24 h after the imposition of mechanical force, and wounded cells were generally of normal ultrastructure, indicating that cells in skin can survive membrane wounding. We propose that plasma membrane disruptions are an overlooked but probably common occurrence in cells residing in tissues such as gut and skin that are normally exposed to mechanical stress in vivo, and that such disruptions provide the physical basis in vivo for a previously unrecognized and diffusion-mediated route for molecular traffic directly across the plasma membrane into and out of living cell cytoplasm.
Effects of agents that modulate intracellular signal transduction, macromolecule synthesis and cytoskeleton assembly
Authors: Rosen Eliot M. , Meromsky Leonid , Goldberg Itzhak , Bhargava Madhu , Setter Eva
Published: April 2021

Scatter factor (SF) is a cytokine that causes cohesive epithelial colonies to ‘scatter’ into isolated cells and stimulates epithelial cell migration. To investigate SF’s mechanism(s), we screened agents that modulate various intracellular processes for effects on scattering of Madin-Darby canine kidney (MDCK) cells. Selected agents were studied in quantitative migration assays using microcarrier beads. Agents that activate the adenylate cyclase (AC) pathway caused mild to moderate inhibition of scattering and migration, while modulators of Ca2+/calmodulin pathways had little effect on scattering. In contrast, phorbol esters (PMA, PDD) and protein kinase C (PKC) inhibitors (staurosporine, H-7, 7,8-dihydroxy-chlorpromazine) markedly enhanced and accelerated scattering; PMA and staurosporine also stimulated migration. Diacylglycerol analogues (e.g. diC8), naphthalenesulfonamide PKC activators (SC-9, SC-10) and inactive phorbol esters (e.g. 4a-PDD) did not potentiate scattering, while PKC depletion by 48 h pre-incubation with PMA markedly stimulated scattering. Thus, PMA-enhanced scattering may be related to down-modulation of PKC. Scattering was blocked by inhibitors of protein and RNA but not DNA synthesis; SF- and agent-stimulated migration were ablated by cycloheximide. Scattering and migration were inhibited by an anti-microfilament (cytochalasin B) but not anti-microtubule (e.g. colce-mid) agents. These findings suggest that SF-induced epithelial mobility may be mediated, in part, by protein synthesis, alterations in protein phosphorylation (?inhibition of PKC), and actin filament reorganization. They indicate directions for further studies.
Chemotaxis to cyclic AMP and folic acid is mediated by different G proteins in Dictyostelium discoideum
Authors: Kesbeke Fanja , Van Haastert Peter J. M. , De Wit René J. W. , Snaar-Jagalska B. Ewa
Published: April 2021

Mutant Frigid A (fgdA) of Dictyostelium discoideum is defective in a functional Ga2 subunit of a G protein and is characterized by a complete blockade of the cyclic AMP-mediated sensory transduction steps, including cyclic AMP relay, chemotaxis and the cyclic GMP response. Folic acid-mediated transmembrane signal transduction was investigated in this mutant; the results show that: (1) cell surface folic acid receptors are present in fgdA mutants. (2) Folic acid induces intracellular responses, including activation of guanylate cyclase and chemotaxis. (3) The inhibitory effect of GTP on folic acid binding to membranes is present. (4) GTPγS binding and high-affinity GTPase are stimulated by folic acid. These data strongly suggest that folic acid receptors are coupled to guanylate cyclase and chemotaxis via a Ga protein that is different from Ga2. The results imply that surface receptors for cyclic AMP and folic acid are coupled to different G proteins.
Taxol influences control of protofilament number at microtubule-nucleating sites in Drosophila
Authors: Mogensen Mette M. , Tucker John B.
Published: April 2021

Control of protofilament number has been investigated using Drosophila wings at a stage when 15-protofilament microtubules assemble under normal conditions. Microtubule nucleation still progressed at the usual microtubule-nucleating sites in the presence of taxol. However, provided taxol was introduced before microtubule nucleation began, few microtubules with 15 protofilaments assembled. Most microtubules were composed of 12 protofilaments (a previously undetected value for Drosophila) or 13 protofilaments (which is the value for micro tubules in most eukaryotic cells). Unexpectedly, a comparatively mild challenge to control of nucleation (in vitro wing culture) also promoted assembly of 13-protofilament microtubules. Hence, the microtubule-nucleating sites may possess a relatively labile control specifying 15 protofilaments superimposed upon that for maintaining 13-proto-filament fidelity.
An endogenous carbohydrate-binding protein of baby hamster kidney (BHK21 C13) cells : Temporal changes in cellular expression in the developing kidney
Authors: Foddy Louise , Stamatoglou Stamatis C. , Hughes R. Colin
Published: April 2021

Asialofetuin (ASF) coupled to Sepharose has been used to isolate a Af r30000 protein from Triton X-100 extracts of the baby hamster kidney cell line BHK21 C13. Binding to ASF-Sepharose was specific for terminal β-galactosyl residues. The lectin requires detergent for optimal solubilization and binding is independent of Ca 2+ or reducing reagents. The lectin was labelled in a lactoperoxidase-catalysed iodination of intact BHK21 C13 cells, suggesting that it is associated with the cell surface. Antibodies to the lectin identify in Western blotting cross-reactive components in established cell lines of kidney (MDCK, NRK) and non-kidney (L, CHO, 3T3) origin. In young adult hamsters, the lectin is expressed in colon and duodenum and in lesser amounts in ileum, stomach, lung, liver and testes but is absent in kidney. The lectin is expressed in late embryonic and newborn hamster kidney but expression declines during 14 days after birth. Immunofluorescent staining of cryostat sections of newborn hamster kidney and intestine show that the lectin is expressed at apical epithelial surfaces. The presence of the lectin at the luminal surface of kidney tubules suggests a tubular origin for the BHK21 C13 cell line. Possible functions of the Mr30000 lectin in kidney development are discussed.
Desmoplakin II expression is not restricted to stratified epithelia
Authors: Angst Bright D. , Nilles Laura A. , Green Kathleen J.
Published: April 2021

Desmosomes are major intercellular junctions found in association with intermediate filaments in epithelial, cardiac and arachnoidal tissue. Desmoplakins I and II (DPI and II) are highly related proteins localized in the innermost part of the desmosomal plaque and are candidates for linking intermediate filaments (IF) to the desmosomal complex. While investigators agree that DPI is present in all epithelia, they disagree on the distribution of DPII. Some have reported DPII to be restricted to stratified tissue and have furthermore suggested that the expression of DPII may be linked to stratification.

We have compared the expression of DPI and II at the mRNA and protein levels in cell lines derived from simple, transitional and stratified epithelia. Northern blot analysis revealed DPI and II mRNA to be present in all cell lines as well as simple and stratified epithelial tissues. However, DPII mRNA could not be detected in cardiac muscle tissue. Immunoblotting and immunoprecipitation demonstrated the presence of DPI and II in all cell lines at the whole-cell protein level as well as in association with cytoskeletal fractions. Immunofluorescence staining was used to correlate the biochemical findings with the localization of DPI and II. While most cell lines exhibited typical intercellular and in many cases cytoplasmic DP staining, T24 cells exhibited predominantly diffuse and dotty cytoplasmic staining. In addition, we investigated whether changes in DPI and II expression occurred following calcium-induced cell contact formation and stratification in the human pharyngeal cell line, FaDu. No significant changes in mRNA or whole-cell protein levels were observed during a period of 5 days following the calcium switch. However, immunoblotting revealed a significant increase in DPI and II levels in the insoluble protein pool during desmosome formation. These observations indicated a possible recruitment of soluble DPI/H into an insoluble pool after induction of desmosome assembly by the calcium switch, consistent with earlier reports for MDCK cells.

In summary, our results suggest that the expression of DPII is not strictly linked to stratification or differentiation; however, the apparent absence of DPII mRNA from cardiac muscle suggests it may not be a constituent of all desmosomes.
The influenza resistance murine Mx1 gene is constitutively expressed in the epithelia of the gastrointestinal, respiratory and uterine tracts
Authors: Chang Kin-Chow , Gerlach Gerald , Fernandes Kenneth , Lida Joshua , Goldspink Geoffrey
Published: April 2021

The murine Mxl gene confers specific resistance against influenza in the inbred A2G mice and in vitro have been shown to be inducible with type I but not type II interferons. Contrary to expectation, we found by in situ hybridisation widespread Mxl expression along the epithelia of the gastrointestinal, uterine and respiratory tracts in uninduced A2G mice. Several lines of evidence, including further enhancement of Mxl expression during organ culture and gnotobiotic mice analyses, indicated that this apparent constitutive epithelial Mxl expression was a locally induced response to stimuli present in the respective lumina. This phenomenon may be a feature found in other interferon-inducible and interferon genes.
The importance of mitotic control for establishment of developmental competence in Acanthamoeba castellanii
Authors: Jantzen Helga , Schulze Ingrid , Stöhr Michael
Published: April 2021

Acanthamoeba castellanii cells become growth arrested at different positions of the G2 phase of the cell cycle. Cells arresting at the competence position of G2 either develop into cysts in response to starvation or enter the mitotic division cycle in response to fresh nutrient medium. In cells arresting elsewhere in G2 growth can be initiated. The cell cycle position at which cells become growth arrested is dependent on the mode of cell cycle progression which, in turn, is strongly dependent on physical parameters of the cultivation conditions. Cells arresting at the competence position progress through cell cycles in which developmental competence and the so-called ‘growth-associated’ or ‘M phase-specific’ histone Hl kinase activity oscillate in levels. Hl kinase activity increases rapidly at the onset of mitosis and decreases to its basal level immediately after the completion of mitosis. In this case, peak levels of developmental competence slightly precede peak levels of Hl kinase activity. In contrast, cells arresting elsewhere in G2 are advanced through their cell cycle, i.e. undergo mitosis at reduced G2 phase length and smaller cell size compared with normal. The premature mitosis correlates in time with a rapid increase of Hl kinase activity. However, the extent of its activation is increased and its inactivation is slower so that Hl kinase activity does not decrease to its basal level during the shortened G2 phase. Ln this case a cell cycle period in which establishment of developmental competence takes place is lacking. In response to cycloheximide or vanadate, which delay the onset of premature mitosis, the competence period can be restored. Hl kinase activity is likely to represent p34cdc2 protein kinase activity, which has been shown in a wide variety of eukaryotic cell types to play a key role in regulating mitosis. Therefore, the results indicate that the mechanisms regulating development are coupled to controls acting over mitosis. In vitro translation patterns suggest that the length of G2 and/or a low basal level of Hl kinase activity is (are) important for regulating the cellular content of competence- and development-specific RNA species.
In vitro study of placental trophoblast calcium uptake using JEG-3 human choriocarcinoma cells
Authors: Tuan Rocky S. , Moore Claire J. , Brittingham Jacqueline W. , Kirwin James J. , Akins Robert E. , Wong Mayme
Published: April 2021

During human fetal development, placental syncytiotrophoblaste actively transport calcium from the maternal to the fetal circulation. Two functional components, a cytosolic Ca2+-binding protein (CaBP) and a Ca2+-ATPase have been identified in the syncytiotrophoblaste of the chorionic villi. We report here the calcium uptake properties of a human choriocarcinoma cell line, JEG-3, which was used as an in vitro model cell system for the syncytiotrophoblaste. In culture, JEG-3 proliferated as large syncytial aggregates expressing typical syncytio-trophoblast markers. 48Ca uptake by JEG-3 was a substrate- and temperature-dependent, membrane-mediated active process that exhibited linear kinetics for up to 7min. Both the CaBP and the Ca2+-ATPase were expressed by JEG-3, on the basis of biochemical, histochemical, immunochemical and/or mRNA asssays. Immunohistochemistry and in situ hybridization revealed that JEG-3 cells were heterogeneous with respect to the expression of the CaBP. The Ca2+-ATPase activity of JEG-3 was similar to the placental enzyme in terms of sensitivity to specific inhibitors, and was detected histochemically along the cell membrane. Fura-2 Ca2+ imaging revealed that calcium uptake by JEG-3 was not accompanied by a concomitant increase in cytosolic [Ca2+], suggesting a specific Ca2+ sequestration mechanism. The involvement of calciotropic hormonal regulation was evaluated by studying the response of JEG-3 to 1,25-dihydroxy vitamin D3. Calcium uptake was significantly stimulated in a dose-dependent manner by a 24-h treatment of the cells with 1,25-dihydroxy vitamin D3 (optimal dose ∼0.5 nM); the CaBP level doubled whereas steady-state CaBP mRNA did not, suggesting that CaBP expression was regulated by 1,25-dihydroxy vitamin D3. These observations strongly suggest that the JEG-3 human choriocarcinoma cells should serve as a convenient in vitro model system for studying the cellular mechanism and regulation of transplacental calcium transport.
Responses of growth cones to changes in osmolality of the surrounding medium
Authors: Bray Dennis , Money Nicholas P. , Harold Franklin M. , Bamburg James R.
Published: April 2021

The possible involvement of osmotically generated hydrostatic pressure in driving actin-rich extensions of the cell surface was examined using cultures of chick neurons. Estimation of the excess internal osmotic pressure of chick neural tissue by vapor pressure deficit osmometry, and of the excess internal hydrostatic pressure in cultured chick neurons using a calibrated pressure pipette, gave upper limits of 10mosM and 0.1 atmosphere (1 atmosphere= 101325 Pa), respectively. Increases in the osmolality of the medium surrounding cultured neurons by addition of sucrose, mannitol or polyethylene glycol by amounts that should eliminate any internal pressure not only failed to arrest the growth of filopodia but caused them to increase in length up to twofold in 3-5 min. Lamellipodia remained unchanged following hyperosmotic shifts of 20 mosM, but higher levels caused a small decrease in area. Reduction of osmolality by the addition of water to the culture fluid down to 50% of its normal value failed to show any detectable change in either filopodial length or lamellipodial area. These observations argue against an osmotic mechanism for growth cone extension and show that the growth of filopodia, in particular, is unlikely to be driven by osmotically generated hydrostatic pressure.

In contrast to the short-term effects on growth cone morphology, the slower elongation of the neuritic cylinder showed a consistent osmotic response. Growth rates were reduced following addition of osmolytes and increased in rate (as much as sixfold) following addition of water to the culture medium. Although the interpretation of the effects on growth is not straightforward, they raise the possibility that osmotically derived internal pressure may contribute to the elongation of the microtubule-rich axonal cylinder.
The existence of mammifers anterior to the deposition of the lias, demonstrated from, the microscopic structure of a bow from the river-bed deposit, lyme regis
Authors: Dennis J. B. P.
Published: April 2021

Through the kindness of the President of the Geological Society, a Paper of mine was read before the Society on the 19th of March last, in which I brought under their notice certain facts which seemed to me strongly to indicate the existence of Mammifers at a period when the Lias had not been deposited, and in a deposit well known by the name of the Bristol bone-bed. Since then, through the kindness of Professor Owen, Dr. J. E. Gray, and Professor Huxley, I have had great opportunities of carrying on my investigations, and I trust that, though errors may be found in my inductions, the result of my inquiries will be found to have added some fresh truth to the treasures of science.
Notes on some new species and varieties of british marine diatomaceæ
Authors: Roper F. C. S.
Published: April 2021

The greater part of the British fresh-water species of Diatomaceæ, from the facility with which they are obtained, and the frequent opportunities for collecting them offered to every observer with a microscope, have probably been already described; but that this is not the case with the marine species, is shown by the great additions lately made to this class by the researches of Dr. Gregory, Mr. Brightwell, and others; and, as they appear to have been hitherto somewhat neglected on our Southern coasts, I hope to draw more particular attention to this abundant field of original observation by pointing out the best means of obtaining the marine species, and at the same time propose to describe a few of the more peculiar forms that have occurred to myself within the last two years.
Beiträge zur normalen und pathologischen histologie der cornea. Contributions to the normal and morbid histology of the cornea
Authors: His Wilhelm , His W.
Published: April 2021

If the results arrived at by Dr. His in this unassuming little work are confirmed by future observers (and the whole style and manner of working of the author lead us to entertain a strong expectation that they will be), it will prove to be one of the most valuable ‘Contributions’ which has been made for a long time, not only to normal and morbid histology, but to physiology. For one of the most important problems presented to the physiologist at the present moment is, what is the influence of conditions upon nutrition ? or, in other words, how far and in what manner can the vital activities of the elementary histological components of tissues be checked, excited, or otherwise modified by influences from without ? It is from their bearing on this great question that Dr. His’s inquiries appear to us to derive their preponderant interest, though there are many other points of view in which they are eminently worthy of attention.
Introduction to Cryptogamic Botany
Authors: Berkeley M. J.
Published: April 2021

There is no department of natural history that has been more indebted for its progress to the employment of the microscope than that of the structure of Cryptogamic Plants. So little was the nature and structure of these plants known, that Linnæus applied to them the term Cryptogamia, on the supposition that no process of reproduction existed in them analogous to that which occurred in the stamens and pistils of higher plants. The history of the discovery of the reproduction of these plants, by the agency of sperm-cells and germ-cells, is one of the most brilliant pages in the records of microscopic research. Although their structure has been well described and illustrated in the works and papers of Lindley, the Hookers, Henfrey, Berkeley, Broome, Thwaites, Ralfs, and the late William Smith; till the publication of the present work by the Rev. M. J. Berkeley, we had no book in our language especially devoted to the consideration of their structure and affinities. Few persons could bring to this task more qualifications than Mr. Berkeley. He has devoted unusual powers of observation and careful research to the study of the Fungi, and is known for his work on the British forms of this family, wherever the science of botany is cultivated. In this work he has devoted the same qualities of mind to the revision and criticism of all that has been done by other observers in the remaining families of the Cryptogamia, and has produced a volume that will be valued by all who are engaged in the study of this most interesting and important branch of scientific investigation. Not only does Mr. Berkeley’s work give a very complete account of the various families of Cryptogamic plants, but it contains a large amount of philosophical reflection and sound advice, which cannot but be useful to the young student. In his introductory chapter he especially draws attention to the value of researches on the lower plants; and points out the errors those are likely to fall into, who, whilst skilful in the use of the microscope, have neglected the first principles of scientific inquiry. We give the following extract as an example.
On plagiogramma, a new genus of Diatomaceæ
Authors: Greville R. K.
Published: April 2021

The only known species of the new genus of Diatomaceæ, which 1 propose to establish in this communication, was published by my late friend, Professor Gregory, in 1857, in his paper “On the Marine Diatomaceæ of the Clyde” (‘Trans. Roy. Soc. Ed./ vol. xxi), under the name of Denticula staurophora. Soon afterwards, two or three other evidently nearly allied diatoms were observed by Professor Walker-Arnott and myself in Californian guano; and my attention having been thus attracted to these remarkable forms, I lost no subsequent opportunity of searching for them, both in guano preparations and recent gatherings. Some I have detected in a gathering obtained by washing small algæ picked up on the coast of Jamaica; and several very interesting species occurred in the scrapings of conch shells from Nassau, New Providence, kindly sent to me by Mr. Norman, of Hull. The Caribbean Sea appears to be particularly rich in Diatomacece; and there can be no doubt that this curious little group will be further enlarged when observers shall have been supplied with additional materials from its shores.*
The Mycetozoa.—A Contribution Towards the Knowledge of the Lowest Animals
Authors: De Bary Dr. Anton
Published: April 2021

Dr. De Bary’s object in the above paper, is to prove that the tribe of organisms, heretofore brought together under the general name of Myxogastric fungi, are not fungi; that they are, in fact, not vegetables, but animals. The author does not undertake, at present, to fix exactly their systematic position, but he assigns them a place provisionally, between (the Rhizo pods and the Gregarinæ. Should his views be ultimately established, the Zoologists will (as M. Tulasne has remarked), thereby receive compensation in respect of the Corallines, which the botanists have appropriated; but we cannot help thinking, that a great deal more evidence will be required; and much more discussion will have to be gone through, before botanists will be content to assent to the transfer of the Myxogastric fungi to the animal kingdom.
A Manual of the Sub-kingdom Protozoa
Authors: Greene Joseph Reay
Published: April 2021

We learn from the preface to this little volume, that it “is the first of a series of similar treatises on the several departments of the animal kingdom;” and from the cover of the hook we find that it is intended to herald a series of scientific manuals. A manual of systematic botany is in preparation by the distinguished professor of botany in the University of Dublin. Professor Greene’s work is a capital commencement of the series. In beginning with the Protozoa, the author had a subject of some difficulty with which to commence, but just such a one as an ardent and industrious student would be glad to deal.
Some further Experiments and Observations on the Mode of Formation and Coalescence of Carbonate Of Lime Globules, and the Development of Shell-Tissues
Authors: Rainey G.
Published: April 2021

As I believe it is generally admitted, especially by those who have examined my specimens of carbonate of lime, as it occurs in shell-tissues, and compared them with the analogous artificial forms, that both are formed in the same manner; and as in this case the experimental investigation of the artificial process will furnish the best clue to a precise and certain knowledge of the natural one, by showing more clearly how much is due to physical agency, I have been anxious to extend and improve my former process for obtaining the globular form of carbonate of lime by making the conditions more like the natural ones, and by so performing the experiments that the changes, which the carbonate undergoes in its passage from an apparently amorphous state to large globules, may, as they are taking place, allow of being examined by the microscope.
The Honey-Bee, its natural history, habits, anatomy, and microscopical beauty
Authors: Samuelson James , Hicks J. Braxton
Published: April 2021

The author of this little work, and his able assistant, Dr. Hicks, are well known for a former attempt at making known the structure of some of the more frequent forms of the lower animals around us. We spoke very highly of The Earthworm and the Housefly‘when they appeared; and we feel called on to give the same meed of praise to ‘The Honey-bee’. Although Mr. Samuelson has gone over much ground that was previously well trodden, in his account of the structure and history of the habits of the bee, he has succeeded in making the subject his own, and treating it in a way that demands our praise in a literary point of view. The general structure of the bee is highly interesting, and we do not know of any descriptions of the minuter points of the anatomy of these insects which can claim to be more minute and accurate than those contained in this little volume. As much of the matter contained in this department of the volume has not appeared before in a popular form, we take the liberty of making rather a long extract from the chapter descriptive of the eyes of the bee. The author expresses himself as indebted for this part of his work to the labours of Dr. Hicks, who is well known to the cultivators of microscopical science for the extent and accuracy of his observations.
Notes on the presence of Animal Life at vast depths in the Sea, with Observations on the Nature of the Seabed as bearing on Submarine Telegraphs.
Authors: Wallich G. C.
Published: April 2021

Dr. Wallich has just returned from an arduous undertaking. At a very short notice, animated by the ardent zeal by which he is distinguished, he started as naturalist on board the Bulldog, commanded by Sir L. M’Clintock, and employed in the survey of a proposed telegraphic route to North America. The first-fruits of this expedition, in anticipation, doubtless, of a further and more detailed account of his observations, have been printed by Dr. Wallich, under the above title; and a very interesting communication it is. It is scarcely too much to say, that Dr. Walii ch’s observations, on this voyage, will have the result of considerably modifying the views of naturalists, as to the necessary limits placed by depth in the ocean to the existence of animal life. The results of former observations of the soundings obtained in the survey of the route for the Great Atlantic Telegraph showed the strong probability, if not the absolute certainty, that animal life could be maintained at the enormous depth of between four and five miles; in fact, that the bed of the ocean, throughout a vast tract, was composed of a soft bed, formed of the shells of defunct and living Foraminifera, for the most part Globigerina;—a fact perfectly in accordance with what might have been concluded from our knowledge of the composition of Chalk, and other similar formations of a more recent date; as for instance, that which occurs near Oran, in Algeria. But Dr. Wallich’s late dredgings, if the term can be used, have shown, that not only can the lowly organized Rhizopod exist far “removed from light of day,” and under a pressure of many tons on the square inch, but that creatures of the high type of organization presented in the Echinodermata are also capable of existing at a depth of 1260 fathoms, or in water condensed under a pressure of about 4000 lbs. on the square inch and what is more marvellous still, that animals of that complex structure can bear to be suddenly brought to the surface, without apparent injury. Besides this, “on two occasions, living specimens of Serpula, one from 680 fathoms, and in conjunction with a living Spirorbis, other free Annelids and two Amphipod Crustaceans were also taken alive at 445 fathoms.”
New Experiments Relating to What is Termed Spontaneous Generation
Authors: Pasteur M. L.
Published: April 2021

Since the author’s last communication to the Academy on the subject of the origin of “ferments,” and on what is termed “spontaneous generation,” his attention has been directed to several points of particular interest in the question, and which are still attended with great difficulties, although their explanation is comprised in his previous labours.
Catalogue of Transparent Injected Preparations
Authors: Smith  , Beck
Published: April 2021

Messrs Smith and Beck having sent us up a selection from the transparent injected preparations which they now have on sale, we feel we shall be doing a service to our readers by calling their attention to them. We believe these preparations are not made in this country; but from whatever part of the world they are obtained, they claim the merit of being the most successfully mounted microscopic preparations that have yet been, offered to the public for sale. In the catalogue the preparations are arranged under distinct heads, according to the part or organ of the animal system from which they are obtained; and, perhaps, we cannot give our readers a better idea of the nature and variety of these preparations, than by referring to them under the various subdivisions adopted in the catalogue.
Micboscopical Society, January 9th, 1861
Authors: Fabbants R. J. , Mackrell John , Dumas A. J. , Aubert Alfred
Published: April 2021

Mr. H. Deane made some observations in reference to some new diatom discs exhibited in the meeting, which had been forwarded from an old member of the Society, Mr. John Coates, now resident and in medical practice at South Yarra, near Melbourne, where the siliceous shells had been found.
On The Circulation in the Wings of Blatta Orientalis and Other Insects, and on a New Method of Tnjecting the Vessels of Insects
Authors: Moseley H. N.
Published: April 2021

Whilst working in the laboratory of Prof. Ludwig, at Leipzig, this spring, I obtained a number of specimens of JB. orientalis, to look for nerve-endings in their salivary glands. I happened to examine their wings under the microscope, and finding a remarkably perfect circulation in them, was led to examine the wings of other insects, and study the subject somewhat closely. Several observers who have written on the circulation of insects have given lists of the insects in which they have observed the phenomenon.
On the Endothelium of the Body-Cavity and Blood-Vessels of the Common Earthworm, as Demonstrated by Silver-Staining
Authors: Power D’arcy
Published: April 2021

The application to invertebrata of the methods of histological research devised by students of the organization of vertebrate animals, is likely to yield interesting results. At the suggestion of Prof. Lankester, I have examined the structure of the lining membranes of the body-cavity and blood-vessels of the Earthworm, by aid of the well-known method of silver-impregnation, which has yielded such valuable results in connection with the serous membranes and vascular structures of Vertebrata in the hands of von Recklinghausen and of Klein.
On the Development of the Conceptacle in the Fucaceæ
Authors: Bower F.O.
Published: April 2021

The first careful notice of the conceptacle which I have met with is that in the ‘Phycologia Generalis’ of Kützing (1843).
The Bacillus of Leprosy
Authors: Hansen G. Armaner
Published: April 2021

It was not my intention to make any of my investigations on this subject public at present, but as not only Dr. Edlund, to whom in the preceding year I showed preparations, and mentioned that I considered leprosy a parasitic disease, in his little work on ‘Leprosy’ speaks of its precise origin as something that he has discovered in the form of “micrococci,” but also Dr. Neisser, of Breslau, who passed some portion of this summer in Bergen has just published the result of his investigations of those preparations that he made while here, and as these results also point out that in general, the preparations are filled with “bacilli” which he supposes to be peculiar to leprosy, and as its “contagium”—I feel myself called upon to announce what I have attained to, up to the present time, in my researches after the same “contagium,” and, this, partly to assert my priority with reference to this discovery, and partly in order to advance those details in research which I omitted to announce on account of the still uncertain result in my report to the Medical Society in Christiania, 1874, concerning my investigations into the etiology of leprosy. In this report I have briefly stated that I often, indeed generally, found, when seeking for them in the leprous tubercles, small rod-shaped bodies in the cells of the swelling,1 whilst, on the contrary, I never found such “bodies” in blood newly taken from leprous patients, in which, however, Dr. Edlund declares he has seen the “microccoci” described by him. This observation of Dr. Edlund I must, however, after having examined several times, quite lately, blood taken from a leper, consider as unreliable. I found very often, on the contrary, after preserving the blood-preparations in a damp room, that in the course of a few days there appeared articulated threads, which, I believe, must be considered as a fungous growth, and which never appeared in blood-preparations taken from either healthy or syphilitic people. After having employed myself for a lengthened period in these investigations of the blood, I proceeded to those of the tubercle, and shall communicate, as follows, a few of the memoranda I made during that time.
“Ueber den Bau und das Wachsthum der Zellhaüte.”
Authors: Strasburger von E. , Ward H. Marshall
Published: April 2021

A Further communication on the subject of the vegetable cell, by the author of the well-known book, ‘Zellbildung und Zelltheilung,’ cannot fail to interest all who are busied with morphological investigations. In the present work, from the active pen of Professor Strasburger, we are introduced to a large number of new facts, supplemented by a brilliant series of hypothetical considerations. However opinions may differ as to the value of the latter, there can be little doubt about the importance of the former, and no better plea for special work in biology could be demanded than such a book and its natural connection with previous investigations by the same author.
Carnoy’s Cell Researches
Authors: Lee Arthur Bolles
Published: April 2021

In the year 1883 there was circulated in the book-trade a prospectus of a forthcoming work on comparative cytology, by J. B. Carnoy. This prospectus contained some very remarkable drawings of cell-structures. It was followed in 1884 by the first instalment of the work it announced, 1 La Biologie Cellulaire.’ This work contains a not inconsiderable quantity of new views, or modifications of old views, which, if true, are certainly highly important. In 1885 Carnoy launched a new journal, ‘La Cellule,’ intended to be devoted to the discussion of the entire biology of the animal and vegetal cell. The first volume of this collection contains a splendid monograph on the spermatogenesis of the Arthropoda, by G. Gilson, and an equally elaborate and searching investigation of the processes of cell division in the same sub-kingdom, by Carnoy.1 All this painstaking work has hitherto been flatly ignored, in some cases for reasons that are manifestly deficient in vis logic a, as, for example, that the author quotes the Talmud. I suspect that much of the neglect of Carnoy’s work is due to reasons of this order; and, believing that many of his results are very valuable, I venture to ask to be allowed to give some account of them here.
On Dinophilus Gigas
Authors: Weldon W. F. R.
Published: April 2021

In the spring of last year Mr. Shipley brought to Cambridge a few specimens of a Dinophilus, which he had found in Mount’s Bay, near Penzance. These he was kind enough to place at my disposal; and in April last I was able myself to procure a larger number of specimens from the same locality.
Illustrations of the Structure and Life-History of Phytophthora infestans, the Fungus causing the Potato Disease
Authors: Marshall Ward H.
Published: April 2021

Some time ago I was commissioned to prepare for the Science and Art Department, South Kensington, a series of drawings illustrating the structure and life-histories of certain parasitic fungi; the intention being that these drawings should eventually be enlarged to form wall-diagrams suitable for museum and teaching purposes. I soon found that if the drawings were to be what I should wish them to be—i. e. to form a properly connected series, and to be taken from original preparations—the task promised to develope into one of greater magnitude than had been anticipated. In fact it became necessary to go over the entire field.
On the Nuclei of the Striated Muscle-Fibre in Necturus (Menobranchus) lateralis
Authors: Macallum A. B.
Published: April 2021

While examining, several months ago, some preparations made for the purpose of demonstrating the mode of nerve termination in the striated muscle-fibre of Necturus, I found many of the isolated nuclei to possess on their surface furrows and striations hitherto undescribed, and which, I now believe, are of importance in determining the structure of the contractile element of muscle-substance. A careful study of these nuclei has further revealed other peculiarities which point to a conclusion as to the origin of the contractile element, the muscle reticulum. In view of this, I give a detailed description of the appearances presented by the nuclei, and refer them to their supposed causes.
On Sagitta
Authors: Keferstein
Published: April 2021

Professor Keferstein, of Göttingen, in his recently published ’Investigations on the Lower Marine Animals,’† has a short communication entitled “Some Remarks on Sagitta,” of which the following is a translation.
Some Remarks upon Light. A Paper read before the Microscopical Society of Newcastle-upon-Tyne
Authors: Proctor B. S.
Published: April 2021

It can scarcely fail to have struck every microscopist that the white materials of everyday life, when submitted to the keen gaze of microscopical examination, display bright reflecting surfaces and clear transmitting substance ; that black substances are also shining, though in a less degree and having less transparency ; and that the most opaque materials transmit more or less light when in thin section.
On Peculiar Appearances exhibited by Blood-Corpuscles under the influence of Solutions of Magenta and Tannin
Authors: Roberts William
Published: April 2021

The object of the following paper is to give an account of certain observations which seem to indicate that the cell-wall of the vertebrate blood-disc does not possess the simplicity of structure usually attributed to it.
On the Nerve-Cells of the Spinal Cord in the ox
Authors: Hendry W.
Published: April 2021

The careful and patient manipulation required in order to display and mount the nerve-cells of the cord has undoubtedly tended to retard any general knowledge of these most singular and interesting bodies, whose structure and relations have hitherto remained in comparative obscurity. They are numerous and well-defined corpuscles, exceedingly variable in size and form, and furnished with conspicuous circular nuclei and nucleoli, of a yellowish colour, and usually presenting towards one or other extremity a pigmentary matter of a peculiar kind. They are also furnished with one or more processes, and hence have been designated, unipolar, bipolar, or multipolar cells. The processes in question are described as anastomosing filaments, or as branches connecting one cell with another, or as continuous with the peripheral nerve-fibres. In some cases, again, they appear to have free terminations in the surrounding tissues. But these are questions upon which all observers are not satisfactorily agreed; nor is this a matter of surprise when we consider the extremely minute portions subjected to microscopical examination, the necessary preliminary preparation required, and the unavoidable disturbance of parts, all tending to interfere with if not wholly to destroy the normal arrangement of such delicate structures. Nevertheless, keen research, multiplied observations, and careful description of what is seen, may eventually lead to a more perfect knowledge of the distribution of those parts wherein at present some ambiguity may exist.
Spermatogenesis in Myxine glutinosa
Authors: Cunningham J.T.
Published: April 2021

In a paper published in this Journal in 1886 (2) I described the generative organs and the peculiar protandrous hermaphroditism of Myxine. That description included a brief and incomplete account of the spermatogenesis, of which I had not been able, for want of leisure and material, to make a more deliberate investigation. In 1888, Dr. Fridtjof Nansen, then Zoological Curator at the Bergen Museum, published in the ‘Aarsberetning/ or Annual Report of that Institution, the results of a study of the reproductive organs of the animal in question (3). Dr. Nansen’s researches were, as he himself states, suggested to him by my paper, and in a great many important matters he fully confirms my results. But with regard to the development of the spermatozoa he contradicts and rejects with perhaps unnecessary emphasis all my statements, and comes to the conclusion that I never saw the normal spermatozoa at all.
Notes on Two Acanthodriloid Earthworms from New Zealand
Authors: Benham W. Blaxland
Published: April 2021

In the summer of last year (1890) I received, through the kindness of Professor Jeffrey Bell, of the British Museum, some earthworms for identification. They were collected by Mr. Vaughan Jennings in New Zealand, at Manngatua, south of Dunedin, who generously allowed me to retain them for further examination. I regret that so much delay has occurred in preparing my report for publication, for I almost completed my observations on them during last summer vacation, but continuous work since September last prevented me putting certain finishing touches to the descriptions and figures till August of the present year (1891).