514 GELIDIACEAE. 



penicillata. N. corymhosa was originally described from Key West, but it has 

 recently been found in Bermuda by Hervey (Buildings Bay, Phyc. Bor.-Am. 

 £036) and by Collins (St. George's). 



Gelidium crinale (Turn.) J. Ag., like other species of Gelidium, has none 

 of the exceedingly delicate, almost microscopic filaments that characterize the 

 two preceding genera. It forms dark red or blackish mats 1 to 3 inches high, 

 the lower parts terete or slightly flattened, scarcely coarser than a bristle, the 

 numerous mostly flattened branches and branehlets irregularly two-ranked, 

 the ultimate often spatulate, becoming J-^ of a line broad. It occurs on 

 stones and rocks near low-water mark, as at Walsingham and at Dingle Bay. 

 (Phyc. Bor.-Am. 2089.) 



Gelidium caemlescens Klitz. (?). The type of this species came from 

 New Caledonia in the South Pacific, but a more or less similar plant occurs 

 in Bermuda and the West Indies. Its branches are broader (J— § line) than 

 those of the preceding and are rather more regularly disposed, and the color 

 of the plant is more red-purple and often iridescent. 



Gelidium pusillum conchicola Piccone, creeps on shells of mussels, etc., its 

 linear or spatulate ascending branches being usually only i of an inch high or 

 less, and ^-J of a line broad. (Phyc. Bor.-Am. 2183.) 



Gelidium rigidum (Vahl) Grev. [Gelidiopsis rigida (Vahl) Web. -v. Bosse] 

 is a rather coarse rigid cartilaginous plant with a repent base and regularly 

 or often very irregularly pinnate or bipinnate erect branches 1-3 inches high. 

 It has been placed by most recent writers in the genus Gelidiopsis of the 

 family Sphaerococcaeeae, though in absence of known cystocarps its generic 

 position is not wholly clear. In the character of its apical cell and of its 

 usually indistinct central axis it does not seem very different from Gelidi/um 

 cartilagineiim, which is allowed to remain in this genus, but it diverges from 

 typical species of Gelidium in having a thallus that is essentially terete 

 throughout and in the often irregularly disposed, not always two-ranked 

 branches. The tetrasporangia occur on somewhat enlarged conic or conic- 

 terete apices of some of the ultimate branehlets, easily recognizable under a 

 hand-lens. It has been found in tide-pools and on stones in shallow water, 

 as at Harris Bay, in the Walsingham region, etc. (Alg. Exs. Am. Bor. 142, 

 and Phyc. Bor.-Am. 2090.) 



Family GIGARTINACEAE. 



Gigartina acicularis (Wulf.) Lamour. forms tangled tufts IJ-S inches 

 high. It has a dark red, subterete or slightly flattened, freely and irregularly 

 branched thallus, mostly i—k line broad, with awl-shaped or taper-pointed, 

 often recurved, ultimate branehlets. This widely distributed species has been 

 found by Colling on flat rocks overhung by a cliff at Tucker's Town. (Phyc. 

 Bor.-Am. 1884.) 



Family RHODOPHYLLIDACEAE. 



Catenella Opuntia pinnata Harv. is a small red-purple plant, mostly i-l 

 inch long, dichotomous, trichotomous, or subpinnate, more or less narrowed or 



