. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen : Rhodophyceæ of the Danish W. Indies. 305 As far as I know the tetrasporangia are up to this date the only known organs of fructification of this plant. The discovering of a small piece of a male plant and of a female one, was there- fore of much interest. Neither the antheridia nor the cystocarps show any more essential peculiarities; both kinds of fructiferous organs are very hke those, e. g. found in Polysiphonia. As, in the case of the stichidia, the antheridial stands (Fig. 308) are found in the tricho- blasts and originate f
. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen : Rhodophyceæ of the Danish W. Indies. 305 As far as I know the tetrasporangia are up to this date the only known organs of fructification of this plant. The discovering of a small piece of a male plant and of a female one, was there- fore of much interest. Neither the antheridia nor the cystocarps show any more essential peculiarities; both kinds of fructiferous organs are very hke those, e. g. found in Polysiphonia. As, in the case of the stichidia, the antheridial stands (Fig. 308) are found in the tricho- blasts and originate from the first side-branch of while the whole side-branch is employed in the development of the stichidium, this nor- mally having no branch- lets, this side-branch in the male plant has one to three branchlets be- sides the terminally pla- ced antheridial stand. The antheridial stands are cylindrical to spindle-shaped, with an obtuse apex. At their base they have a stalk composed mostly of three short cells and, at their summit, two small sterile cells. The development of the antheridial stands takes place in the follow- ing manner: the branch at first is divided by transverse walls in a number of short cells above each other (Fig. 309 a) where- upon these again are divided: firstly by longitudinal walls (Fig. o09 6), later by walls in various directions into a great number of small roundish-polygonal cells at the pheriphery. From these the antheridia are formed. The procarps originate from the second segment of the tricho- blast (Fig. 310). This becomes polysiphonous, consisting of the central cell and the five pericentral ones as always in the case of Dansk Botanisk Arkiv. Bd. 3. Nr. 1 (1919). 20. Fig. 308. Lophocladia Irichoclados (Mert., C. Ag.). Schmitz. Part of a filament with triclioblasts, two of which bearing antheridial stands. (About 100 : 1).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for r
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