74 COLLINS AND HERVEY. 



ROSENVINGIA Borgesen. 



R. INTRICATA (J. Ag.) Borgesen, 1914, p. 182; P. B.-A., No. 2173; 

 Asperococcus intricatus J. G. Agardh, 1847, p. 7; Striaria intricata 

 Tickers, 1905, p. 59; 1908, p. 41, PI. XXIV. Harris Bay, Feb., 

 Hervey, with plurilocular sporangia. 



FAMILY MYRIOTRICHIACEAE. 

 MYRIOTRICHIA Harvey. 



M. REPENS Hauck, 1879, p. 22; Kuckuck, 1899, p. 21, PI. Ill (of 

 reprint); P. B.-A., No. 2025; Dichosporangium repens Hauck, 1885, 

 p. 339, fig. 141. In fronds of Castagnea Zoster ae, Cooper's Island, 

 April, Collins. The creeping filaments bear abundant unilocular 

 sporangia; the erect filaments bear each a terminal cluster of pluri- 

 locular sporangia; no unilocular sporangia were seen on the erect 

 filaments. Streblonema sphaericum, with both kinds of sporangia, 

 accompanies the Myriotrichia. As pointed out by Kuckuck, it is 

 practically impossible to distinguish the two species when both bear 

 only unilocular sporangia, as is often the case; the presence of erect 

 filaments in Myriotrichia and their absence in Streblonema is the only 

 distinguishing character. 



FAMILY MESOGLOIACEAE. 

 CASTAGNEA Derbes & Solier. 



C. ZOSTERAE (Mohr) Thuret, fide Borgesen, 1914, p. 184, figs. 

 144-145; Castagnea mediterranea P. B.-A., No. 1879. Kemp, as 

 Mesogloia vermicularis, M. Griffithsiana and M. Chordariae; Castle 

 Harbor, Bailey's Bay, March, Wadsworth; Shelly Bay, Jan., Castle 

 Harbor, Feb., Hervey; Cooper's Island, April, Collins. As this 

 plant seems to be the same as that from the Danish West Indies, we 

 provisionally give the same name used by Borgesen. It was distrib- 

 uted by us as C. mediterranea (Kiitz.) Bornet, but is not Cladosiphon 

 mcditerraneus Kiitzing, as shown by comparison with an authentic 

 specimen of the latter, for which we are indebted to the kindness of 



