1917] Gardner: New Pacific Coast Marine Algae I 389 



Stipe arisiii<r from an irregular coiiieal-shaped, somewhat fibrous 

 holdfast, flexible, rather sparingly forked, 5-15 cm. long, 4-6 mm. 

 diam., triangular in cross-section, giving rise to flattened branches 

 alternately arranged just below the termiiuil growing point ; flattened 

 branches coriaceous, flexible, becoming rigid and brittle wlien dry, 

 dying back after fruiting, leaving a permanent angular scar on the 

 stipe, when young divided into rounded alternate lobes by a deep 

 sinus rounded at the base ; the lobes of the lower and middle portion 

 of the branches become 2-3 times pinnatified, and the upper lobes 

 become repeatedly divided into cylindrical branches terminating in 

 numerous receptables; air vesicles develop in the flliform branches, 

 solitary or a few in a series but separated 1-3 mm. from each other, 

 spherical, smooth, 2-3 mm. diam. ; whole plant 4-7 dm. long ; color 

 of living plant light brown, turning black when dry ; perennial ; 

 dioecious. 



Growing in the upper sublittoral belt at Avalon, Santa Catalina 

 Island, California. 



Type numbers are 188975 and 188976, herbarium of the Univer- 

 sity of California. 



From time to time within the past few years, fragments of the 

 upper part of a plant resembling Cystoseira Osmundacea, especially 

 resembling the upper part of forma expansa of that species, have 

 been collected along the coast of southern California. Until recently 

 the plants had not been seen growing in position, the fragments found 

 always having been cast ashore. On this account it was presumed 

 that the species was a deep-sea form, as nobody had seen it growing 

 in position. In a previous paper (1913, p. 336) I suggested that these 

 fragments would probably be found to belong to an undescribed 

 species as soon as the whole plant could be discovered. While visiting 

 Santa Catalina Island, about twenty-five miles off the coast from 

 San Pedro, California, I had the good fortune to discover the same 

 species growing in position in the locality from which the fragments 

 cast ashore on the mainland had probably come. Many fragments 

 were seen floating in the vicinity. The plants grew in abundance in 

 the harbor at Avalon, mostl}- in the u]iper sublittoral zone. The 

 discovery was made in March, 1913. 



On account of profuse branching in the upper parts of the fronds, 

 when the water is quiet the plants present the appearance of clumps 

 of densely branching shrubs about two feet high. 



It is not a simple task to decide what to do with a new plant 

 belonging to the cyst-bearing group of the Fucaceae. Since the estab- 

 lishment of the genera Cystoseira Ag. ('21), Blossevillea Dec'sne 

 ('40), Cystophora J. Ag. ('41), and Cystophyllum J. Ag. ('48), so 



