. The microscope and its revelations. (3) Two cells lyingside by side cast off their old valves, and each grows into anauxospore, without any previous fusion, or any visible interchangeof contents ; this is the commonest type of all. (4) A true conjuga-tion takes place ; the protoplasmic contents of the two cells fuse. FIG. 447.—Self-conjugation (?) of Melosira italica (Aulacosira creiiulataThwaites): 1, simple filament; 2, filament developing auxospores ; a, b, c, succes-sive stages in the formation of auxospores ; auxospore-frustules in successive stages,ci, b, c, of multiplication. together
. The microscope and its revelations. (3) Two cells lyingside by side cast off their old valves, and each grows into anauxospore, without any previous fusion, or any visible interchangeof contents ; this is the commonest type of all. (4) A true conjuga-tion takes place ; the protoplasmic contents of the two cells fuse. FIG. 447.—Self-conjugation (?) of Melosira italica (Aulacosira creiiulataThwaites): 1, simple filament; 2, filament developing auxospores ; a, b, c, succes-sive stages in the formation of auxospores ; auxospore-frustules in successive stages,ci, b, c, of multiplication. together into one, and this mass grows into an auxospore. (5) Beforeconjugation, the protoplasm of each of the two cells divides before-hand into two daughter-cells, and two auxospores are formed bythe fusion of a daughter-cell from each mother-cell with thedaughter-cell of the other one lying opposite to it; this is the mostcomplicated process (Amphora ovalis, Epithemia l!li/>«-lodia yibbn, A:c.). The most curious phenomenon presented by diatoms is un-doubtedly their power of movement, which induced Ehrenberg andthe other early observers of these organisms to place them erro-neously in the animal kingdom. :dthough it affords no evidence ofconsciousness. This power of movement, if not common to a
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectmicrosc, bookyear1901
