498 TJniversiiy of California PiiblicaUons in Botany [Vol. 8 



Growing on rocks, shells, etc., in the middle and lower littoral 

 belts. Reported from various localities from the Bay of Unalaska, 

 Alaska, to Monterey Bay, California. 



J. Agardh, Sp. Alg., vol. 1, 1848, p. 62 ; Reinke, Atlas Meeresalg., 

 1889, pis. 5, 6, Algenflora, 1889a;, p. 48 ; Setchell and Gardner, Alg. 

 N.W. Amer., 1903, p. 253 ; Collins, Holden and Setchell, Phyc. Bor.- 

 Amer. (Exsicc), no. LV (?). Cruoria verrucosa Aresehoug, in 

 Linnaea, 1843, p. 264, pi. 9, figs. 5, 6. 



The measurements given for this species by different authors are 

 quite variable. The dimensions of the zoosporangia given in our 

 diagnosis above are taken from Kuckuck (1894, p. 244) and our speci- 

 mens agree ; these were taken as representing the average typical size. 

 Farlow (1881, p. 87) gives the measurements of the zoosporangia as 

 38/x long and 19/. wide. De-Toni (1895, p. 312) gives 65-80-lOOfi 

 long, and 15-30,/j, wide. The material quoted from Unalaska is all 

 sterile. Careful comparison with mature material from the eastern 

 and European coasts may show that our California specimens are of 

 a distinct species. 



The material distributed from southern California under B. ver- 

 rucosa in Collins, Holden and Setchell, Phycotheca Boreali-Americana, 

 no. LV, is very young and the rows of cells are mostly perpendicular 

 to the substratum instead of being curved as is the case with the 

 typical U. verrucosa. It seems quite possible that this plant belongs 

 to some other species, or possibly to another genus. 



4. Ralfsia hesperia S. and G. 



Thallus flattened, coriaceous, circular in outline, adhering firmly 

 to the substratum by the whole lower surface, at times developing 

 rhizoids, 3-4 cm. diam., 1-1.5 mm. thick, with concentric zonation ; 

 color light yellowish brown, dark on drying; paraphyses 290-360/. 

 long, very slightly clavate, 9-12 cells long, 8-11/. broad at the apices, 

 densely crowded with chromatophores above, but few below ; cells of 

 paraphyses 7-9 times as long as broad below, 2-3 times above ; sori 

 extensive, often confluent ; zoosporangia broadly clavate, 120-140/i 

 (up to 180/.) long, 28-34/1 broad; gametangia unknown. 



Growing on rocks in the upper littoral belt. Central California. 



Setchell and Gardner, Phyc. Cont., VII, 1924, p. 2. 



Ralfsia hesperia is very closely related to R. verrucosa in morpho- 

 logical characters. The plants are, as a rule, smaller in diameter and 



