. Text-book of botany, morphological and physiological. Botany. CARPOSPOREM. 3*3 slender branches now shoot out at opposite points, and grow upwards on the outside of the helix; one of these developes more quickly, reaches the uppermost coil, and becomes closely attached to it by its apex (B, p). This branch is the pollinodium. Conjugation takes place between its apex and that of the carpogonium, the cell-walls being absorbed at the point of contact, and the protoplasmic contents of the two cells commingle. Soon afterwards new filaments sprout out from the lower part of the pollinodium and of
. Text-book of botany, morphological and physiological. Botany. CARPOSPOREM. 3*3 slender branches now shoot out at opposite points, and grow upwards on the outside of the helix; one of these developes more quickly, reaches the uppermost coil, and becomes closely attached to it by its apex (B, p). This branch is the pollinodium. Conjugation takes place between its apex and that of the carpogonium, the cell-walls being absorbed at the point of contact, and the protoplasmic contents of the two cells commingle. Soon afterwards new filaments sprout out from the lower part of the pollinodium and of the carpogonium, which increase in number, cling closely to the spiral (C), and finally entirely envelope it. From these filaments a layer of polygonal cells (D) is formed by numerous transverse divisions, which envelopes the carpogonium. The cells of the enveloping layer grow inwards as papillae which become septate (E), While the enveloping layer is increasing in size, the cavity of the perithecium, which is thus enlarged, is filled up by the papillae, and they finally insert themselves between the coils. FIG. 208.—Development of Ettrotium repens (after De Bary). A small portion of a mycelium, with the conidia-bearing hyphce c and young ascogonium (or carpogonium) as: B the spiral ascogonium as with the pollinodium P; C the same, beginning to be surrounded by the threads out of which the wall of the perithecium is formed; D a perithecium; E, F. section of young perithecia, w parietal cells,/"pseudo-parenchyma, as ascogonium; G an ascus; i/an ascospore. of the carpogonium which have now become looser. These papillae become divided by septa into numerous cells of similar diameter, so that at last the space between the enveloping layer and the coils of the carpogonium is filled by a pseudo-parenchyma (F). During these processes a large number of septa arise in the carpogonium, and soon there shoot from its cells numerous commencements of branches, which penetrate on all s
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1882
