. Text-book of botany, morphological and physiological. Botany. OOSPORES. 28l The Confervacese, like the QEdogonieae, consist of rows of cells or segmented fila- ments, which either remain unbranched, as in Cbmtomorpba, or become branched, as in Cladophora, Rhi%oclonium> Stigeoclonium (Fig. 3), Draparnaldia^ Ghxtophora1. With re- ference to their reproduction, it is only known that macro- and micro-zoogonidia are formed in the cells of the filaments (Chsetomorpha, Cladophora), the sexual significance of which is still unknown2; and that in the other above-mentioned plants resting-spores are
. Text-book of botany, morphological and physiological. Botany. OOSPORES. 28l The Confervacese, like the QEdogonieae, consist of rows of cells or segmented fila- ments, which either remain unbranched, as in Cbmtomorpba, or become branched, as in Cladophora, Rhi%oclonium> Stigeoclonium (Fig. 3), Draparnaldia^ Ghxtophora1. With re- ference to their reproduction, it is only known that macro- and micro-zoogonidia are formed in the cells of the filaments (Chsetomorpha, Cladophora), the sexual significance of which is still unknown2; and that in the other above-mentioned plants resting-spores are formed in certain cells of the filaments. Pringsheim suggests that they are probably equivalent to oospores, but that they are produced parthenogenetically. E. Fucoide^. The Fucacese comprise, in the narrow limitation proposed by Thuret3, a few genera of large marine Algae, the thallomes of which, often many feet long, have a. Fig. 184.—Fucusplatycarpus (after Thuret); A end of one of the larger branches (natural size) \ yyfertile branchlets ; B transverse section of a conceptacle; d the surrounding epidermal tissue ; a the hairs projecting from the mouth; b hairs in the interior; c oogonia, e antheridia (cf. Fig. 2, p. 3). greenish-brown colour and a cartilaginous consistency. They are fixed to stones or other bodies by a branched attachment-disc. The thallomes branch dichotomously, and the further development is also frequently forked, but in other cases sympodial, as in Fig. 184. The ramifications, irrespectively of later displacements, all lie in one, plane. 1 [The Ulvacese are probably allied to the Confervaceae. In them the cells are arranged so as to form a delicate membrane.] 2 [According to Areschoug (Nov. Act. reg. soc. sci. Upsal. ser. 3. vol. IX) the microzoogonidia of Cladopkora conjugate in pairs.] 3 G. Thuret, Ann. des Sci. Nat. II. 1854. p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for rea
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