152 COLLIXS AXD HEKVET. 



Island, Feb., Farlow, washed ashore; Castle Harbor, Gravelly Bay, 

 April, Collins; Gravelly Bay, Dec., Hervey. Two large plants Avere 

 collected in a narrow "chasm" in the rocky shore between Tucker's 

 Town and Walsingham House, growing in company with Halymcnia 

 bermudensis, but while the latter grew plentifully at low water mark, 

 the Platoma began about 5 dm. below, and seemed to extend down. 

 Farlow's plants and ours from the cave at Gravelly Bay are smaller 

 and of firmer substance; the Castle Harbor plants larger and looser, 

 probably on account of being more developed. 



Genus incertae sedis. 

 PoRPHYRiDiUM Nagcli. 



P. CRUENTTJM (Eng. Bot.) Nageli, 1849, pp. 71 & 139, PI. IV. H; 

 Tremella cnienta Eng., Bot., 1807, PI. 1800. Roadside, Jan., Farlow. 

 Forms a bright red film on the ground; is widely distributed and in 

 northern countries is common in hothouses. It has been placed by 

 different authors among green, blue-green and red algae respectively, 

 but the latest investigations incline to the last. See Brand, 1908, 

 p. 413. 



