. A handbook of cryptogamic botany. Cryptogams. FLORIDE^ .(Lnix.), and a few other genera, the 'frond' becomes densely incrusted by a deposit of calcium carbonate, giving to the so-called 'corallines' .the external form and appearance of miniature corals. J The ordinary non-sexual propagative organs of the Floridese are bright red motionless spores, commonly formed in fours in the mother- jCell, and hence known as tetraspores (the sphaerospores of Agardh), arid the cell in which they are produced as The four spores â ,are sometimes arranged in a row, when they are called
. A handbook of cryptogamic botany. Cryptogams. FLORIDE^ .(Lnix.), and a few other genera, the 'frond' becomes densely incrusted by a deposit of calcium carbonate, giving to the so-called 'corallines' .the external form and appearance of miniature corals. J The ordinary non-sexual propagative organs of the Floridese are bright red motionless spores, commonly formed in fours in the mother- jCell, and hence known as tetraspores (the sphaerospores of Agardh), arid the cell in which they are produced as The four spores â ,are sometimes arranged in a row, when they are called zonate,; more often as quadrants of a sphere, when they are cruciate : rarely there are only one or two, or occasionally eight. In-'thesUlvacese, Lemaneacese,. Fig. iji.âCmuama. attenuaia Ag. a, branch (x 40) ; i, apex of branch (x 100) ; c, lower ; portion of branch with tetrasporanges(x 100). (After Kiitzing.) and in some Nemalieas they are altogether wanting. The tetraspores (see' fig. 231) may be formed in the six following ways :â(i) The whole contents of the sporange become a single spore ; (2) the contents divide into two equal parts by a transverse wall; (3) they divide into four quadrants by two successive bipartitions ; (4) they divide into four tetrahedra by simultaneous quadripartition ; (5) they divide into four by three parallel transverse walls ; (6) the contents divide into more than four spores. On germination the tetraspores may give birth either to sexual or to non-sexual individuals. In the monosiphonous Florideae the tetrasporanges are usually formed at the expense of the ultimate branchlets. In other forms they are most commonly found scattered. 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 Bennett, Alfred W. (Alfred William), 1833-1902; Murray, George Robert Milne, 1858-. London,
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