— 203 — 



by Falkenberg in "Rhodomelaceen des Golfes von Neapel", p. 

 229, tab. 22, fig. 3. 



On the other hand they come very near to those of Acantho- 

 p/iora orientalis J. Ag. as figured by Okamura in "Icones of Ja- 

 panese . Algae", vol. 1, pi. VIII, fig. 6 — 7. When the stichidial bodies 

 are short the tetraspores are developed near the base, when longer 

 they are nearer to the tip. Sometimes the tetraspores are also de- 

 veloped in the tip of the shoots which bear the tetrasporic ramuli. 



Only very seldom have I found stichidia in form like those of 

 Acanthophora Delilei Lamx. but it was always only a single one 

 and the other stichidial branches were all with spines. (Fig. 18 C.) 



So far as I know the antheridia of the genus Acanthophora 

 have only been found in Acanthophora orientalis. Askenasy has 

 in "Forschungsreise S. M. S. Gazelle" IV Theil, Botanik (Algen) p. 

 48, tab. IX, fig. 11 and 12, described and figured it. In my material 

 of Acanthophora spicifera male plants were rather richly present 

 and the antheridial stands seem to be in good accordance with 

 those of A. orientalis. (Fig. 18 A). And they also remind one 

 of the well-known antheridial stands of the genus Chondria, so 

 splendidly figured by T buret and Bornet in "Etudes phyco- 

 logiques", pag. 88, pi. 45 et 46. 



The antheridial stands are seemingly developed on the first side- 

 branch upon the trichoblasts, the name Rosen vinge^) has given the 

 hair-like shoots of the Rhodomelaceas (Fig. 19 ^,), but are most probably 

 terminal, in accordance with what is the case in Polysiphonia. These 

 trichoblasts are apparently dichotomously ramified but as well known 

 (Gfr. Rosenvinge, I.e. p. 441), they are in reality monopodially 

 ramified. The trichoblast itself is commonly very perishable and the 

 fully developed, ripe antheridial stands are therefore placed terminally 

 upon the shorter or longer lower cell of the trichoblast. The antheri- 

 dial stand itself is a flat disc-formed body most often with a rather 

 irregularly formed circumference. The margin is composed of large, 

 oblong, thick-walled clear cells; inside these both the surfaces are 

 densely covered by the spermatia-forming cells, through which in the 

 middle of the antheridial stand we see a system of filaments ramified 

 subdichotomously in the same plane. (Fig, 18 A.) These filaments 

 Falkenberg (1. c. p. 201) who has followed the development of 



^) Rosenvinge, L. K older up, Sur les organes pilifbrmes des Rhodome- 

 lacees (Oversigt over det kgl. danske Videnskabernes Selskabs Forhandlinger 

 1903, Nr. 4.) 



