V. CERAMIACE^. 231 



current stem and pyramidal outline ; branches lateral, directed to every side, simple 

 or alternately decompound, densely clothed with short, pinnato-multifid, fastigiate 

 plumules ; ramuli divaricate, subulate ; articulations of the stem and larger branches 

 veiny, once or twice as long as broad, of the ramuli about twice as long as broad, 

 cylindrical or contracted at the nodes ; tetraspores very minute, tripartite, near tlie 

 tips of the ramuli. J. Ag. Sp. Alg. 2, p. 53. Harv. Phyc. Brit. 1. 136. Phkbothaui- 

 nion tetragommi, Kiitz. Sp. Alg. p. 654. CaUithaimiioii brachiatum, Harv. Phyc. Brit, 

 t. 137. Conferva tetragona, D'dhv. Conf. t. 65. E. Bot. t. 1690. 



Hab. Newport, Rhode Island, Mr. Olney., Dr. Durkee. Narragansett Pier, Mr. 

 Hunt. Seaconnot, Mr. C. Congdon. Green port. Prof. Bailey, (v. v.) 



Fronds three to four inches high. Colour., a fine lake or red brown. Substance 

 gelatinoso-cartilaginous. 



The American specimens here described are not quite so robust as the European 

 plant, but some of them are in other respects very similar. Others, again, show a 

 tendency to pass into C. Baileyi, and almost shake my opinion of the validity of 

 that species ; and yet its extreme forms are so different from the nearest form of 

 C. tetragonunu, that I dare not, as species are at present understood, unite them. 



3. Callithamnion Baileyi, Harv. ; frond setaceous, shrub-like, with a percurrent 

 stem ; branches lateral, directed to every side, simple or alternately decompound, 

 densely ramulose ; lesser branchlets spirally inserted, somewhat plumulate, or 

 fasciculato-multifid, zig-zag ; ramuli alternate, subulate, incurved, acute ; articula- 

 tions of the lower stem veiny, twice or thrice as long as broad, of the branches 

 swollen at the nodes, thick -walled, without veins, three or four times as long as 

 broad ; of the ramuli cylindrical, about thrice as long as broad ; tetraspores solitary, 

 elliptical, on the inner faces of the ramuli ; favellai binate. Harv. in Bail, list of 

 Alga;. Sill. Journ. vol. 4, 2d. Ser., p. 38. (Tab. XXXV. B.) Var. /3 boreale; stem 

 pellucidly articulate, its medial articulations four or five tim.es as long as broad, 

 those of the branches cylindrical, and of the ramuli longer than in var. a. Var. y 

 Rochei ; more slender than usual and very plumose ; the ramuli elongate, patent, 

 crowded at the ends of the branches. Var. S squarrosum; plumules short and little 

 divided ; ramuli short, squarrose. 



Hab. New Brighton, Prof. Bailey. Abundant in New York Bay, Prof. Bailey. 

 Messrs. Hooper, Pike, ^c, W. H. H. ^, Boston Bay in various places, Mrs. Mudge^ 

 Dr. Durkee, Miss Brewer, ^x. 7, New Bedford, Dr. Roche. ^, Red Hook, J/r. Hoo- 

 per, (v. V.) 



Fronds tufted or solitary, shrub-like. Stems as thick as hog's bristle, two to three 

 inches long, generally undivided and closely beset on all sides with similar, un- 

 divided, long lateral branches, the lowest of which are longest, the rest successively 

 shorter, so that the outline of the frond is pyramidal. In luxuriant specimens 



