. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 121 All the larger filaments are covered with a cortical layer (comp. Fig. 132) formed by the rhizoids growing out from the base of the branchlets; in the young parts of the branches this cortical layer is not yet developed. The tetrasporangia (Fig. 131) of wdiich Derbes et Solier, 1. c, pi. 18, flg. 7, give a figure are placed terminally upon the short ramuli. The cells from w^hich the tetrasporangia originate give rise also to some short filaments which are more or less curved round the tetra


. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 121 All the larger filaments are covered with a cortical layer (comp. Fig. 132) formed by the rhizoids growing out from the base of the branchlets; in the young parts of the branches this cortical layer is not yet developed. The tetrasporangia (Fig. 131) of wdiich Derbes et Solier, 1. c, pi. 18, flg. 7, give a figure are placed terminally upon the short ramuli. The cells from w^hich the tetrasporangia originate give rise also to some short filaments which are more or less curved round the tetra- sporangia forming in this way a kind of involucre. The tetrasporangia are spherical, tetrahedrally divided; their diameter reaches a length of about 75^. The branch which carries the tetrasporan- gia-bearing branchlets are, as pointed out by Zerlang, mostly with- out a cortical layer. The antheridial stands (Fig. 132) are spherical bodies termin- ally placed upon the ramuli and, in a similar way as the tetraspor- angia, surrounded by curved cells growing out from the cell which carry the antheridial stand. This consists of numerous short filaments radiating out from the middle of the stand and at the end of which the spermatia are formed. The diameter of the antheridial stand reaches a length of about 60,«. Duby has 1. c, pi. II, fig. 4 given a figure of a branch with antheridial stands. In the branches which carry the ramuli wdth antheridial stands I have mostly found the cortical layer very well developed. The cystocarps are spherical and terminally placed upon short branches. Regarding their shape and development upon the whole Bornet et Thuret, Schmitz and especially Zerlang have given detailed descriptions and the first mentioned have further given very fine illustrations, I. c, pi. 48. To these descriptions. Fig. 132. Wrangelia penicillata C. Ag. Part of a male plant with antheridial stand. (About 200:1).. Please note that these images are extracted from scanned page


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