Page:Journal of botany, British and foreign, Volume 34 (1896).djvu/310

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284 NOTES ON SABCOMENIA MINIATA AG. from which the pollinoids arose. The walls of this little hori- zontally stretched cell were indistinct, but distinct strands of proto- plasm were clinging to it. I could not see what became of them. The contents of the upper big cell had entirely vanished, but on each side articulated dichotomous filaments had developed. They rose a little above the surface of the unchanged middle nerve of the antheridium ; this facilitated of course the distribution of the pollinoids, and strengthened my opinion as to the function of the pedicel-cell. The apex of the articulated filaments was in some cases very small, in others larger (from 2, 7 to 8, 1 /x, fig. 8). I saw no pollinoids issuing from the top cells, and do not know whether each is the mother-cell of a single pollinoid or whether they undergo still further changes. The beautiful researches on antheridia by the late lamented Mr. Buffham* show that this is not altogether impossible. The cystocarps arise about the middle of the branch, generally nearer to its base. I was not fortunate enough to find trichogynes, nor could I distinguish the carpogonium. The youngest stages I saw consisted of three big cells full of protoplasm lying in the centre of the branch at the place of the central tube. These big cells were already surrounded by a low elliptic wall, the future pericarp. The pericentral tubes on one side of the branch had divided by horizontal walls, and the cells resulting from this partition had grown out at right angles on their former longitudinal axis. They had yielded in the middle for the future ostiole, and each cell surrounding this ostiole was an initial cell of the wall of the pericarp. These initial cells were divided by horizontal walls, and each segment was partitioned as in the case of the lateral tubes in the stem by two oblique walls, cutting off two cortical cells. These last ones remain short, but become very broad, and constitute the beautiful symmetric outer wall of the pericarp. The tubes that have given off the cortical cell layer stand apart from one another at the inner side of the pericarp ; they remain thin, and each of their cells is twice as long as a cortical cell. Very young pericarps of Sarcomenia delesserioides have the same mode of growth, but sub- sequent divisions make the pericarp of this plant more differentiated. By the subsequent growth of the procarp tufts of branching filaments arise, the top cells of which produce each a pear-shaped spore, set free by a slit in the membrane. Several spores were lying in the ostiole of the pericarp. When the cystocarp is fully developed it looks as if it were borne on a little stalk, and had been developed at the top of a branch, for the upper part of the branch bearing the cystocarp is pushed aside by the growth of the base of the cystocarp, and looks as if it were an appendage of the cystocarp. This is, however, not the case, all young cystocarps rising from the middle and near the base of the fruit-bearing branch. Prof. Farlow+ has described under the name of Tanioma Cleve- . * Buff ham, T. H,, '"'iiiotes on some FloridecB, Journ. of the Quekett Micr, Cluh, vol. ii. ser. 2, pp. 183-190. 1896. t Farlow, Proc. Avier. Acad. Arts d; Sciences, vol. xii. p. 236.