THE GREEN AL.GAE OF NORTH AMERICA 325 



more slender than the upper part ; when producing spores the 

 fertile cells are much inflated and nearly globular. Fig. 115. 



In upper literal, especially in rock pools, from Me. to W. I. 

 and in Cal. In habit like C. melagonium^ but of .somewhat 

 smaller diameter, lighter color and softer texture ; not firm 

 enough to stand erect when taken from the water. 



Forma Linum (Fl. Dan.) nov. comb. ; Conferva Linnni Har- 

 vey, 1846-51, PI. CL. A ; Chaetomorpha Li mi in Farlow, 1881, 

 p. 47; P. B.-A., No. 22; C. siitoria Harvey, 1858, p. 87; C. 

 Oliicvi Harvey, 1858, p. 86, PI. XLVI.D; C. longiarticitlata 

 Harvey, 1858, p. 86, PI. XIvVI.E. Filaments unattached, 

 prostrate, light green, rather stiff, diam. 200-250 /u., cells about 

 as long as broad. Apparently bearing the same relation to 

 t3 r pical C. aerea as the loose form of C. indagonium does to the 

 attached form. It occurs in great masses of curled and crisped 

 filaments in warm shallow bays, at least from N. S. to W. I. 



5. C. BRACHYGONA Harvey, 1858, p. 87, PI. XIvVI.A; P. 

 B.-A., No. 622. Filaments free, rigid, curved and twisted, 

 forming strata of some extent on rocks or among other algae ; 

 cells 125-175 /j. diam., quite uniformly as long as broad, except 

 just after dividing. Fla., W. I., Mexico. 



Usually found in entangled masses among other algae, in the 

 same way as the more northern Rhizoclonium tortuosum , which 

 has, however, more slender filaments and proportionally longer 

 cells. Rhizocldnium capillare Vickers, 1905, p. 55, appears to 

 belong here. 



6. C. CANNABINA (Aresch.) Kjellman, 1889, p. 55 ; P. B.-A., 

 No. 916. Filaments unattached, soft and rather delicate, 75-100 

 /u, diam., narrow and wide together in the same tuft, or even a 

 single filament tapering from largest to smallest measurement ; 

 cells pretty uniformly 500 to 600 /j. long, being from 3-8 diam.; 

 color light green. Me., Alaska, Washington. 



Northern Europe. 



Usually occurring in tangled masses, distinguished from the 

 other species of northern range by the combination of softer 

 texture, longer cells, and light color. 



7. C. CALIFORNICA Collins, P. B.-A., No. 664 ; 1906, p. 106. 

 Filaments attached by a small disk, about 20 cm. long, straight 

 or flexuous, of uniform diameter throughout, not contracted at 

 the nodes, 20-40 /x diam., cells 1-2 times as long as the diam., 

 rarely 3-4 times. In shallow sandy pools near high water mark, 

 Southern California. 



