420 University of California Publications in Botany [Vol. 8 



main filaments cylindrical, 30-40/* diam., 1-3 times as long as the 

 diameter below, 0.3-0.6 as long above; ehromatophores numerous, 

 small, discoid ; zoosporangia unknown ; gametangia numerous, broadly 

 ovoid, short-acuminate, sessile, 50-100/* (up to 155/*) long, 20-30/* 

 broad. 



Growing on other algae and on Zostera. Vancouver Island (Bay- 

 ard's Point) to southern California (San Pedro). 



Saunders, Phyc. Mem., 1898, p. 152, pi. 19. Ectocarpus granulosus 

 Tilden, Amer. Alg. (Exsicc), no. 359& (not 359a,) • 



Ectocarpus mucronatus seems to be a species of frequent occur- 

 rence in southern California. We have referred a very similar plant 

 from the Puget Sound region (no. 359& of Tilden) here also. It is to 

 be distinguished from other larger feathery species of this genus 

 particularly by its broadly ovoid, abruptly and shortly mucronate 

 gametangia. 



8. Ectocarpus Taoniae S. and G. 



Plate 51, fig. 15 



Fronds diffuse, 0.5-1.5 mm. high, attached by profusely branched, 

 superficial, creeping filaments ; erect filaments simple, narrowed slightly 

 at the base, gradually attenuated above, pilif erous ; cells of the creep- 

 ing filaments cylindrical, 4-6/x diam., those of the erect filaments 8-10/* 

 diam., quadrate below, 4-6 times as long as the diameter at the apices ; 

 ehromatophores short, relatively thick, irregular bands; zoosporangia 

 unknown; gametangia narrowly ellipsoidal, at times slightly curved, 

 mostly sessile on the creeping and on the erect filaments, 20-28/* 

 (up to 40/*) long, 15-20/* broad. 



Growing on Taonia Lcnneb acker ae. San Pedro, California. 



Setchell and Gardner, Phyc. Cont, VI, 1922, p. 413, pi. 46, fig. 15. 



This species forms rather diffuse and even layers, mostly along the 

 margins of Taonia, over whose surface the creeping filaments spread 

 and give rise to gametangia or to erect filaments not over 1.5 mm. 

 high. In many ways it seems like a miniature Ectocarpus Padinae 

 (Buffh.) Sauvageau (1896c-1897tt, p. 30 et seq.). Our species, how- 

 ever, is only about one-half as tall, the cells of the erect filaments about 

 one-half as broad, and the gametangia less than half as large as those of 

 E. Padinae. We have found gametangia only of the "antheridium" 

 type. Ectocarpus Padinae has its creeping filaments entirely endo- 

 phytic while E. Taoniae has them entirely epiphytic. 



