THE ALGAE OF BERMUDA. 133 



latere interiore rami evoluto, loco rami vegetativi, ovoideo-cylindrico, 

 125-130 X 50-60 /i; cystocarpio cellula brevi clavata suffulto, loco 

 rami vegetativi evoluta. 



Prostrate filaments about 65 ^ diam., cells 8-5 diam. long, attached 

 by rhizoids with a large terminal disk; erect filaments 5-8 mm. long, 

 about 50 m diam. at base, gradually diminishing to about 30 jii in 

 ultimate divisions, cells 5-20 diam. long, cylindrical or somewhat 

 clavate, branch-bearing cells strongly clavate; branching usually 

 distant, apparently dichotomous, the axis and branch nearly equal in 

 size and diverging very slightly; tetrasporangia produced on a short 

 branch arising like a vegetative branch, or on two short branches 

 opposite on the axis; tetrasporic branches rarely simple, usually di- or 

 trichotomously divided, the divisions each of a short, clavate cell; 

 tetraspores borne on the ultimate divisions, tripartite, 50-55 /i diam., 

 globose or slightly elongate, with wide pellucid wall; antheridium on 

 the inner side of a branch, occupying the place of a vegetative branch, 

 ovoid-cylindrical, 125-150 X 50-60 yn; cystocarp borne on a short, 

 clavate cell, taking the place of a vegetative branch. Type in Collins 

 herbarium, Smith's Bay, Jan. 18, 1913, Hervey. Also at the same 

 place, Feb., March, Nov., Dec, Hervey. 



The extremely long cells in this species, 20 diameters long being not 

 uncommon, distinguish it from other species of the genus. The erect 

 filaments are usually very sparingly branched, though in the upper 

 half there may sometimes be a branch from every cell; in other cases 

 the erect filament branches only two or three times in its whole length; 

 the branch is hardly distinguishable from the axis, either by size or 

 direction. The tetrasporangium may be terminal on a relatively 

 short cell, 2-3 diam. long, arising from the axis; or this cell may divide 

 one to several times, in the latter case twenty to thirty tetrasporangia 

 being borne at the apices of the divisions, forming a dense, corymb- 

 like cluster. The antheridia appear sessile, as they take the place of 

 normal branches on the inner side of a secondary axis, the unmodified 

 cells of which are shorter than the normal, though not as short as in 

 the tetrasporic clusters; occasionally both branches of a forking are 

 transformed into antheridia. Cystocarps are formed in the same 

 position as antheridia, but the lower cell of the transformed branch 

 remains unchanged. Antheridia were plentiful in material collected 

 in January, tetraspores at all seasons; cystocarps were found in Jan- 

 uary material only, scarce and somewhat immature. The prostrate 

 filaments are affixed by numerous short, stout rhizoids with much 

 expanded terminal disks; occasionally a more slender rhizoid is pro- 



