. Text-book of botany, morphological and physiological. Botany. FIG. 200.—Development of the antheridia of NiteUaJiexiiis. In B, C, and D the protoplasm has been contracted by glycerine. (C, I), the lower of which remains short, while the upper grows into a flask-shaped cell (Fig. 200, D,f, and Fig. ). The globular mother-cell of the antheridium (Fig. 200, A, a) first of all divides into two hemispheres by a vertical wall passing through the axis of the leaf; each of these is divided into two segments by a vertical wall at right angles to the first; in each of the four quadrants a third d
. Text-book of botany, morphological and physiological. Botany. FIG. 200.—Development of the antheridia of NiteUaJiexiiis. In B, C, and D the protoplasm has been contracted by glycerine. (C, I), the lower of which remains short, while the upper grows into a flask-shaped cell (Fig. 200, D,f, and Fig. ). The globular mother-cell of the antheridium (Fig. 200, A, a) first of all divides into two hemispheres by a vertical wall passing through the axis of the leaf; each of these is divided into two segments by a vertical wall at right angles to the first; in each of the four quadrants a third division takes place hori- zontally and at right angles to the two last walls; and the antheridium now consists of four lower and four upper octants of a sphere. Contrac- tion by glycerine clearly shows that each of these divisions of the protoplasmic body is com- pletely effected before the appearance of the cellulose-wall (Fig. 200, B); the second division even takes place before the wall has arisen between the two first-formed halves; and the four quadrants may be made to contract without any wall being visible between them. In Fig. 200, B, the third division has also taken place, the second vertical wall is already formed, and the two quadrants there visible are already divided; but no horizontal wall has yet appeared. In Fig. 200, A, a, are shown the eight octants in perspective together with their nuclei. Each octant now breaks up first of all into an outer and an inner cell (Fig. 200, C); the latter is again divided in all the eight octants (D), so that each octant now consists of an inner, a middle, and an outer cell (D, /', m, e). Up to this time the globe remains solid, and all the cells lie close to one another; but now commences an unequal growth, and with this the formation of intercellular spaces (Fig. 201). The eight outer cells (e) are the young shields, the side-walls of which show even at an earlier period the radial infolding already mentioned; they grow mor
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1882
