. Plant studies; an elementary botany. Botany. THE CiREAT (iROUPS OF ALd/E 259 and reddish-brown) making tliem very attractive. They show the greatest variety of forms, branching fihiments, ribbons, and fihiiy phites prevailing, sometimes branching very profusely and delicately, and resembling of fine texture (Figs. 222, 223, 224, 225, 32G). The diiferen- tiatioii of the thallus into root and stem and leaf-like struc- tures is also common, as in the Brown Algfe. 174. Eeproduction.—Eed Algaj are very peculiar in both their asexual and sexual reproduction. A sjjorangiuni pro- duces just
. Plant studies; an elementary botany. Botany. THE CiREAT (iROUPS OF ALd/E 259 and reddish-brown) making tliem very attractive. They show the greatest variety of forms, branching fihiments, ribbons, and fihiiy phites prevailing, sometimes branching very profusely and delicately, and resembling of fine texture (Figs. 222, 223, 224, 225, 32G). The diiferen- tiatioii of the thallus into root and stem and leaf-like struc- tures is also common, as in the Brown Algfe. 174. Eeproduction.—Eed Algaj are very peculiar in both their asexual and sexual reproduction. A sjjorangiuni pro- duces just four asexual spores, but they have no cilia and no power of motion. They can not be called zoospores, ^Qi" therefore, and as each spo- a. Fig. 2"27. A red alga (Cfd/tf/wnunn/i), show- ing sporangium (A), and tlio tctraspoi-fs discliarged (5).—After Thuret. Fill. 828. A rod alga (Nemri!kw); A, sfKtial braiiolics, showing antheri- dia (a), oogoninm (o) with its trich- ogyne ((}, to which arc attached two spcrniatia (,s'}; B, beginning ot a cystocarp (o), the trichogyne (0 f^till showing ; 0. an almost mature cys- tocarp (o), with the disorganizing trichogyne (/I.—After Knt. rangium always produces just four, they have been called (Fig. 227). Ked Algffi are also heterog- amous, but the sexual process has been so much and so variously modified that it is very poorly understood. The antheridia (Fig. 228, A, ti) develop sperms which, like the tetraspores, have no cilia and no power of motion. To dis-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Coulter, John Merle, 1851-1928. New York, D. Appleton and Company
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1900
