52 COLLINS AND HERVEY. 



Ernodesmis Borgesen. 



E. VERTiciLLATA (Kiitz.) Borgesen, 1912, p. 259, figs. 10-12; 1913, 

 p. 66, figs. 51-54. P. B.-A., No. 1907; Valo?iia verticillata Kiitzing, 

 1849, p. 508; Collins, 1909, p. 373. Kemp, April, St. George's, 

 unnamed specimen in herb.; Castle Harbor, Farlow; Harrington 

 Sound, 3-10 dm., June, Howe; cave by Gravelly Bay, April, tidal 

 stream, Hungry Bay, July, Collins. Generally grows in dense masses 

 of crisp fronds, but easily separable. 



SiPHONOCLADUS Sclimitz. 



1. Primary cell long, erect; substance soft. 1. S. tropicus. 



1. Primary cell short; substance firm. 2. S. rigidus. 



1. S. TROPICUS (Crouan) J. G. Agardh, 1886, p. 105; Borgesen, 

 1913, p. 61, figs. 44-51; Collins, 1909, p. 374; Vickers, 1908, p. 

 20, PI. XVni; Apjohnia troinca Crouan in Maze & Schramm, 1870- 

 77, p. 105. Harris Bay, in pools, a few individuals only, Feb., 

 Hervey. 



2. S. RIGIDUS Howe, 1905, p. 244, PI. XH, fig. 1; PI. XIV; Col- 

 lins, 1909, p. 374, fig. 139; P. B.-A., No. 2169. On flat rock at low 

 water mark, Agar's Island, Dec, Collins. 



Petrosiphon Howe. 



P. ADHAERENS Howe, 1905, p. 248, PI. XV; Collins, 1909, p. 375; 

 P. B.-A., No. 2073. Forming a closely attached crust in pools at 

 Harris Bay, March, Hervey. 



Struvea Sonder. 



S. RAMOSA Dickie, 1874a, p. 316; Murray & Boodle, 1888, p. 280, 

 PI. XVI, fig. 3; Collins, 1909, p. 377. This species was described 

 from specimens collected by Moseley with the Challenger Expedition; 

 there is no record of it since, either here or elsewhere. 



