. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 219 main stem ; below, the side-branches grow out to long filaments like the main stem; higher up they are shorter ; in the uppermost part the ramification is subdichotomous. The plant is not corti- cated and hairs do not occur. The tetrasporangia are generally tetrahedrally divided, though cruciately divided ones occur too (Fig. 206 A). They are sessile, oblique-obovate or nearly roundish when ripe and 35—40 fx broad. The cystocarps are, when fully developed, irregularly lobed, binate. I have
. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 219 main stem ; below, the side-branches grow out to long filaments like the main stem; higher up they are shorter ; in the uppermost part the ramification is subdichotomous. The plant is not corti- cated and hairs do not occur. The tetrasporangia are generally tetrahedrally divided, though cruciately divided ones occur too (Fig. 206 A). They are sessile, oblique-obovate or nearly roundish when ripe and 35—40 fx broad. The cystocarps are, when fully developed, irregularly lobed, binate. I have only found a few procarps; from these it seems evident that the carpo- gonial branch is four-celled ; the carpogonium has a rather long trichogyne (Fig. 206 C). Antheridial plants had not been seen when I previously examined the plant; these have now been found by renewed examination (Fig. 207). The antheridial stands occur in the same places as the tetraspor- angia, lining the upper (inner) side of the filaments. Often they are found only at the summit of the cells, sometimes they occupy nearly the whole upper side of these. They con- sist of a system of short branch- lets in which the uppermost cells are the antheridia. The antheridial stands in the West Indian plant differ rather much from those figured by Buffham^). In his specimens these have a single short axis while in the West Indian plant, as mentioned above, the antheridial stand is composed of several short branchlets. The tetrasporangia, cystocarps and antheridia occur in sepa- rate plants. The chromatophores are parietal and consist of shorter or 1) BuFFHAM, T. H., Notes on the Florideæ and on some newly-found Antheridia (Journ. of the Queckett Microsc. Club, vol. I, Ser. II, 1884, p. 341, pi. X, figs. 4, 5).. Fig. 205. Callithamnion hyssoides Arn. Part of a tetrasporic plant. (About 60 : 1).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readabi
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