B. CRYPTOGAMIA. Cryptogamia Vascularia. Classification of Ophioglossaceae.-K. Prantl gives the following characters of the primary subdivisions of the genera belonging to this family: I. Botrychium. Sectio 1. Eubotrychium. Folia semper glaberrima, stomata in utraque pagina obvia; lamina oblonga vel deltoidea, ad summum bipinnata; petioli fasciculi bini præter binos in pedunculum exeuntes; xylema rhizomatis indistincte seriatum. 5 sp. Sectio 2. Phyllotrichum. Folia juvenilia sæpe et adulta pilosa, stomata infera; lamina deltoidea, bi- ad quinquepinnata; xylema rhizomatis distincte seriatum. 10 sp. II. Helminthostachys. 1 sp. (H. zeylanicum). III. Ophioglossum. Sectio 1. Euophioglossum. Rhizoma hypogæum, præter invo- Structure of Helminthostachys.t-From an examination of Helminthostachys zeylanica from Borneo, K. Prantl discusses the relationship between this and the two remaining genera of Ophioglossaceæ. It is distinguished from both Ophioglossum and Botrychium by its dorsiventral horizontal rhizome, bearing two rows of leaves on its dorsal and several rows of roots on the lateral and ventral sides. Only a single leaf unfolds each year. The course of the fibrovascular bundles resembles that in Botrychium rather than in Ophioglossum ; there is no median bundle; but, on the contrary, there are four placed diagonally to the base of the leaf-stalk. In the absence of any sclerenchyma in the collateral structure of the bundles in the stem and leaf, in the absence of palisade-parenchyma, and in other points, Helminthostachys presents a complete agreement with the other two genera. * Ber. Deutsch. Bot. Gesell., i. (1883) pp. 348-53. Ibid., pp. 155-61. The most striking peculiarity of Helminthostachys is the fertile portion of the leaf, which is densely covered with sporangia, between which are still green portions of the mesophyll. Each of these green portions is the sterile apex of a branchlet. Muscineæ. Structure and Development of certain Spores.*-H. Leitgeb describes a number of examples of departure from the ordinary structure of the spores of cryptogams, viz. where the membrane is composed of two distinctly differentiated coats like the cell-wall of pollen-grains, mostly in the case of Hepatice. With Strasburger he retains the same terminology for the two coats, as for those of pollengrains, viz. extine and intine; but restricts the latter term to an inner layer consisting of pure cellulose. In Osmunda, Ceratopteris, and Gleichenia, for example, there is no true intine or endospore, the inner layer of the spore-membrane being completely cuticularized, and showing none of the reactions of cellulose. Again, in many thinwalled spores which germinate immediately after maturity without any period of rest, as in those of many Jungermanniaceæ, Jungermannia, Lophocolea, Lepidozia, Blasia, &c., there is only one membrane with cuticularized outer layer, the whole of which is used up in the formation of the germinating filament. This is exactly comparable to certain pollen-grains, as those of Naias and Orchis, and in a certain sense also those of Allium fistulosum, where there is only one membrane, the whole of which goes to the formation of the pollen-tube. In other cases again, an inner layer of cellulose employed, in the formation of the germinating filaments, is formed only immediately before the period of germination. In many thick-walled spores of Hepatica, the wall always consists of more than two distinctly differentiated layers; the exospore, extine, or sporoderm being composed of two separable layers, similar to the well-known case of Equisetum. One type of this structure is furnished by Preissia, Duvallia, Reboulia, Fimbriaria, and Plagiochasma. The intine, which turns blue and swells strongly with chloriodide of zinc, is inclosed in a cuticularized layer, which is entirely structureless, and may be termed the extine. This is again inclosed in a third layer with folded protuberances, and elevated like a bladder on one side. But slightly different are the spores of Grimmaldia and Boschia. Corsinia resembles these genera in the structure of the intine and extine, but that of the outermost layer is very different. It is of uniform thickness (as much as 20 μ), and is composed on the dorsal side of polygonal (usually hexagonal) plates, while on the ventral side it is a continuous perfectly smooth shell. Where the dorsal and ventral sides meet, is a projecting seam. In Sphærocarpus, the spores remain united into tetrahedra; but this is not, as in Lycopodium, the result of a simple attachment of the adjacent walls; they are inclosed in a common membrane which is * Ber. Deutsch. Bot. Gesell., i. (1883) pp. 246-56. spores. closely connected with the walls which separate the spores from one another, and consists in fact of layers of the mother-cells of the This membrane is beautifully sculptured on the outside by projecting reticulate bands; and the outer surface of the extine is also similarly sculptured. The history of development of these spores and of the sculpture is gone into in detail; and the author shows that in Corsinia also, and probably also in the other thick-walled spores, the outermost layer is developed, as in Sphærocarpus, from the membrane of the mother-cell, and from its innermost layers, the special mothercell; its formation beginning only after the formation of the true extine, and before the peripheral layers disappear. Fungi. Alkaloids and other Substances extracted from Fungi.*-C. J. Stewart considers that the chemistry of fungi is by no means in a satisfactory state. Many of the existing statements are rendered doubtful by a bad identification of the species. It is also difficult to obtain a sufficient amount of raw material, and its perishable nature interposes another obstacle. Beyond this, the research itself is so difficult and expensive, and the question of profitable result is so remote to ordinary minds, that few qualified chemists have even ventured upon the task. He has accordingly endeavoured to collect together such facts as were scattered in chemical literature, and to explain them as untechnically as was possible with due regard to exactness and truth. The paper is not capable of being usefully abstracted, but it deals with the sugars found in fungi, oils and fats, vegetable acids, resins, colouring matters, trimethylamine, betaine, muscarine, and amanitine (C, H15 NO2). This is identical with the animal bases choline and neurine, and is another link between fungi and the animal kingdom. The production of these bodies artificially, which has been accomplished, is of great interest, as very few natural alkaloids have yet been artificially made; and the success leads us to hope that we may some day produce such medicinal alkaloids as quinine and morphia by chemical means at a cheaper rate. 15 Development of Ascomycetes.t-E. Eidam describes a new genus of fungi, Eremascus, which he regards as, with the exception of Saccharomyces, the simplest type of the Ascomycetes, the entire fructification being reduced to a single naked ascus. It occurs as a white pellicle on the surface of extract of malt. On the muchbranched mycelium there appear, directly on the septa, and on both sides, two precisely similar protuberances, which grow into hypha, and coil spirally round one another even in their youngest stages. The spiral consists of several coils; the apices of the two hyphæ touch one another, and the septum becomes absorbed and their contents completely coalesce. The point of coalescence, which is at first small, increases into a spherical body, which becomes at length separated by septa from the rest of the spiral hyphae. The remainder *Grevillea, xii. (1883) pp. 44–9. † JB. Schles. Gesell. vaterl. Cult., 1883, pp. 175–7. of these hyphae perform the function of conducting cells, and the spherical body becomes an ascus, in which eight ascospores with double cell-walls are formed. The ascus is either quite solitary, or as many as four, with their conducting cells, stand at the same height on the mycelial filaments. The author classes Eremascus among the Gymnoascaceæ. A new species of Gymnoascus is described, G. setosus, found in quantities on a wasp's nest. The author next gives a full description of the history of development of a species of Sterigmatocystis, which forms both conidiophores and asci in a very peculiar way. The perithecia are buried in a large hollow envelope formed of branched filaments, the ends of which swell up into colourless or slightly yellow thick-walled vesicles. Within this cushion are produced the asci. Two very fine hyphæ swell up at their apices, coil, one forming the "nucleus," the other branching and forming the wall of the perithecium. The young fructification has the remarkable property of its colourless contents turning a beautiful blue on addition of ammonia or potash, which changes to red when an acid is added. This colouring substance occurs only in the wall of the perithecium, which, when ripe, is nearly black, and in the ascospores, which are purple. These latter ripen very slowly, and, on germination, produce again the conidiophores of Sterigmatocystis. In Chatomium (C. Kunzeanum Zopf) the origin of the fructification is a single thickish hypha which developes into a distinctly segmented spiral. In the further development Eidam agrees with Van Tieghem rather than with Zopf. A pseudo-parenchymatous ball is formed by the branching of a single spiral filament which is clearly distinguishable from the rest of the mycelium. Conidia of Peronospora.*-M. Cornu gives a more exact description than any previous observer of the mode of abstriction of the conidia of Peronospora. In the middle of the septum which separates the conidium from its hypha is formed a soluble gelatinous layer. This accounts for the rapid development of Peronospora after rainy weather. Cornu disputes the possibility of the oospore directly producing zoospores on germination like the conidia, or rather the sporangium, as de Bary has described in the case of Cystopus. Each oospore, on the contrary, developes into a mycelial filament bearing a sporangium. Their germination depends greatly on moisture and temperature, as also on the depth at which they are buried in the soil. When at a considerable depth they may retain their power of germination for from two to five years. Pleospora herbarum.t-Great confusion has resulted from authors having described under this name different organisms which have no genetic connection with one another. F. G. Kohl has carefully investigated its life-history, having sown the ascospores obtained from * Cornu, M., Etudes sur les Peronosporées. II. Le Peronospora des vignes.' 91 pp., 5 pls., Paris, 1882. See Bot. Centralbl., xv. (1883) p. 274. Bot. Centralbl., xvi. (1883) pp. 26–31. perithecia growing on the stems of Levisticum officinale. On the same host was found also the conidial form known as Alternaria tenuis Nees et Cord. The ascospores of the first form agreed precisely with those of Pleospora Sarcinula Gib. et Griff. Their cultivation gave rise to an abundant mycelium producing Sarcinula-conidia and subsequently perithecia, which again produced ascospores. The second form also gave rise to a mycelium indistinguishable from that of the first, producing immense quantities of green Alternaria-conidia, but no perithecia. The stylospores from pycnidia found on the same host gave rise to a mycelium which produced both pycnidia and Alternaria-conidia; but no proof was obtained of any genetic connection between the Sarcinula-conidia and perithecia on the one hand, and the Alternaria-conidia and pycnidia on the other hand. Cladosporium herbarum, though frequently accompanying all these forms in nature, does not belong to the same cycle of development. It has two conidial forms; firstly, an elongated ellipse, unseptated, which are abstricted in clusters, and have a punctated membrane; secondly, also elliptical but shorter, divided into from one to three chambers, with smooth membrane, not constricted, or very slightly so, at the septa, and abstricted singly from the mycelial branches aggregated in tufts. Epicoccum herbarum has also no genetic connection with Pleospora. Chytridiaceae.-J. Schaarschmidt describes a new species of Chytridiacea, Phlyctidium Haynaldii, and proposes a fresh classification of the species living in water, according to the development of the mycelium. The mycelium appears to be wanting in Olpidiopsis and its allies; the naked plasmodium passes over immediately (Olpidiopsis) or indirectly (Woronina, Rozella, and perhaps Achlyogeton) into several zoosporangia. In Chytridium and Phlyctidium the mycelium is a simple filiform structure; it attains greater development in the genera Rhizidium, Polyphagus, Cladochytrium, Obelidium, Zygochytrium, and Tetrachytrium; it is septated and multicellular in Catenaria, Polyrrhina, and Saccopodium. The author found Chytridium globosum and oblongum parasitic on Ulothrix zonata. Phoma Gentianæ, a new Parasitic Fungus.f-J. Kühn describes a newly discovered fungus, having its habitat on the stems, leaves, and buds of Gentiana ciliata, and takes the opportunity of denying that plants grown in mountainous districts are freer from such parasites than those of the lowlands. Chrysomyxa albida.‡-Under this name J. Kühn describes a new species of parasitic fungus observed on the bramble (Rubus fruticosus) in the Black Forest. It forms small roundish white or yellowish white patches on the under side of the leaves, from 0.25 to 0.5 mm. in diameter. From these project threads which are the unbranched * Magyar Növen. Lapok, vii. (1883) pp. 58-63 (1 pl.) (Magyar and Latin). See Bot. Centralbl., xv. (1883) p. 370. + Landw. Versuchs.-Stat., xxviii. (1883) pp. 455-6. Cf. Journ. Chem. Soc. Abstr., xliv. (1883) p. 1025. Bot. Centralbl., xvi. (1883) pp. 154–7. |