. Botany for high schools and colleges. Botany. â ^*m VOL vox AND ITS ALLIES. 245 bury themselves in the hyaline envelope, and finally pene- trate and become fused into the oosphere {h, Fig. 164). A thick wall now forms⢠upon the fertilized oosphere, and it becomes transformed into an oospore. Thus we have in these plants the transformation of an individual of the colony into an oogo- nium and oos^^here, and the subse- quent fertilization of the latter by spermatozoids^ which are themselves fractional parts of other members of the colony. 326.âThe relationship of the low- er Oophytes with the
. Botany for high schools and colleges. Botany. â ^*m VOL vox AND ITS ALLIES. 245 bury themselves in the hyaline envelope, and finally pene- trate and become fused into the oosphere {h, Fig. 164). A thick wall now forms⢠upon the fertilized oosphere, and it becomes transformed into an oospore. Thus we have in these plants the transformation of an individual of the colony into an oogo- nium and oos^^here, and the subse- quent fertilization of the latter by spermatozoids^ which are themselves fractional parts of other members of the colony. 326.âThe relationship of the low- er Oophytes with the lower Zygo- phytes, as indicated by Volvox and Pandorina, is further shown by the position of SpJiceroplea, an undoubted relative of the Confervacece {Clado- pliora, etc.). Sphceroplea is a free, unbranched, filamentous alga, com- posed of long cells joined end to end (AJ Eig. 165), It produces oospheres in some of its filaments, each cell producing several {B, Fig. 165). While these are forming in one set of filaments, in another the protoplasm becomes broken up into a multitude of elongated, bi-ciliate spermatozoids {G and G, Fig. 165); these escape through lateral openings in the cells, which are formed by the absorption of a part of the wall, and then swim- ming through the water they find their way to corresponding openings in the walls of the. Fig. Wi.âSphcm'opUa annvn Una. A, ordinary filament; r. chlorophyll masses. B, fila- ment consisting of oogonia, the contents breaking up into oospheres ; o, o, openings for entrance of spermatozoids ; s, s, spermatozoids entering the oogonia ; m and k, oospheres at the instant of fertilizat'on ; n, fertilized oosphi^res, now enclosed in a thin cell-wall. C, filament consisting of auther- idia ; s, s, the escaping sper- matozoids, issuing through the openings o o. D, an oospore with its thick coats of cellu- lose. E, zoospore (vegotniive zoogonidium). F, oosphere in the act of being fertilized by a spermatozoid, s. G. spcrmato
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