540 University of California Publications in Botany [you 8 



Derbes and Solier, Mem. phys. alg., 1856, p. 11, pi. 22, figs. 18-20 ; 

 Saunders, Phyc. Mem., 1898, p. 164, pi. 32, figs. 7, 8, Alg. Harriman 

 Exp., 1901, p. 421; Setehell and Gardner, Alg. N.W. Amer., 1903, 

 p. 242; Collins, Holden and Setehell, Phyc. Bor.-Amer. (Exsicc), 

 no. 278; Tilden, Amer. Alg. (Exsicc), no. 522. Ulva sinuosa Roth, 

 Cat. Bot., vol. 3, 1806, p. 327, pi. 12. 



The type of the species was collected at Cadiz by Mertens and 

 from the figures and what we know of the plants of that region is 

 evidently of the more regularly globular or lobed, thin-walled, more 

 or less smooth form of the species, although the description of Roth 

 might seem to apply to the more thick-walled and rugose form. The 

 typical form is less common on our coast but is found in certain 

 localities. As stated above, it seems best, after a study of all of our 

 west coast material, to consider all of our forms under one species 

 and we have arranged them according to the following key : 



1. Fronds thin, membranaceous, surface nearly smooth 2 



1. Fronds thick, chartaceous, surface buUose or strongly lobed 3 



2. Fronds approximately globose, very thin and smooth..!, f. t3rpica (p. 540) 



2. Fronds elongated or irregular, somewhat thicker and less smooth 



2. f. expansa (p. 540) 



2. Fronds expanded to several decimeters, thin but with short, spine-like 



tubercles 3. f. expansissima (p. 541) 



3. Fronds sinuose, strongly buUose and tuberculate, but never lobed 



4. var. tuberculata (p. 541) 



3. Fronds extending into one to several long, finger-like lobes 



5. var. deformans (p. 542) 



1. Colpomenia sinuosa f. typica nom. no v. 



The typical form is thin, about 25-30/x thick, fairly regular in 

 form, usually attached at one place to a filamentous alga, and growing, 

 most commonly, in fairly quiet waters. The clusters of hairs are not 

 sunk in the tissue of the frond and the layers of colorless cells are 

 few (usually 2 to 3). 



2, Colpomenia sinuosa f. expansa Saunders 



Fronds aggregated forming expansions of indefinite size and shape, 

 0.35-0.45 mm. thick, inner layers of cells composed of 5-7 rows of cells. 



Near Avalon Bay, Santa Catalina Island, California. 



Saunders, Phyc. Mem., 1898, p. 164, pi. 32, figs. 4-6; Collins, 

 Holden and Setehell, Phyc. Bor.-Amer. (Exsicc), no. 825. 



