NO. 10 DAWSON : MARINE ALGAE, GULF OF CALIFORNIA 233 



Gulf of California. At least three different entities are present, and, fol- 

 lowing the practice of Setchell and Gardner (loc. cit.), they are here iden- 

 tified as forms. In the case of plants known as C. sinuosa f. deformans this 

 treatment would seem hardly justifiable if based only on specimens of the 

 Gulf of California, since the forma deformans as found in the Gulf is 

 strikingly distinct from the other forms. Indeed, f . deformans is so sharply 

 defined and so different in shape and texture that the author was at first 

 inclined to place it in the genus Scytosiphon. However, it does have a 

 small, bullate, colpomenioid basal portion from which tiny, hollow pro- 

 jections arise, pushing outward and expanding into the long, hollow sacs 

 of the mature frond. Sections at the narrowest point of the stipelike por- 

 tion indicate a hollow structure throughout, unlike Scytosiphon. These 

 specimens are, to the author's knowledge, the most extreme of any re- 

 ferred to C. sinuosa f. deformans. 



Within the Gulf there are relatively few specimens which can be sat- 

 isfactorily identified with C. sinuosa f. typica. Some examples are perfectly 

 smooth, but the greater number are slightly to very strongly tuberculate, 

 all gradations being present in young as well as in old plants. 



Golpomenia sinuosa f. tuberculata (Saunders) S. & G. 



Saunders, 1898, p. 164, pi. 32; Setch. & Gard., 1924, p. 725. 



On almost every rock-shingle beach or in stony places bordering bays 

 and lagoons, these plants are to be found growing in abundant colonies at- 

 tached to the stones. Plants 10-14 cm. in diameter are frequent in some 

 localities. 



Colpomenia sinuosa f. expansissima is undoubtedly a form of C. sinu- 

 osa f. tuberculata, which has achieved very extensive development in a de- 

 tached, floating condition in warm water. This form was described by 

 Setchell and Gardner in 1924 from specimens collected by Johnston, 

 floating on San Francisquito Bay, Lower California. 



D. 422, Pond Island, Feb. ; D. 307, Gonzaga, Jan. ; D. 220, Puerto 

 Refugio, Jan.; D. 351, dredged in 6-20 meters, Punta Peiiasco, Feb.; 

 D. 384, Tepoca Bay, Feb.; D. 636, Feb. (young); D. 90, Turner's 

 Island, Jan.; J. 26, San Francisquito Bay, June; J. 117, Los Angeles Bay, 

 May; M., Brand., La Paz, May. 



Rosenvingea intricata (J. Ag.) B0rg. 

 Plate 52, Fig. 1 



B0rgesen, 1914, pp. 181-183. Encoelium intricatum, Kiitzing, Tab. Phyc. 

 IX, tab. 5. 



