154 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



primary branches ; unilocular sporangia ovate or elliptical, usually sessile, 

 35-55,a X 20-27/^, sometimes on the same filament with the plurilocular 

 sporangia. 



Forming a yellow fleece on sand-colored rocks. San 

 Pedro, California, 1895. Collected by W. A. Setchell 

 (1213). 



The Pacific plant differs from the type and from the 

 form hiemalis in the smaller size of the vegetative parts and 

 the plurilocular sporangia; from the form arctus (Kuetz.) 

 Kuck. in the much narrower vegetative filaments and larger 

 plurilocular sporangia. 



18. Ectocarpus confervoides {Roth) Le Jol. 



EctocarpHs confervoides (Roth) Le Jol., List. Alg. Mar. Cherb., 75, 1880. 



Plants 2 cm. to 3 or 4 dcm. long, attached to the substratum by horizontal 

 creeping filaments, often entangled at the base ; branches alternate, gradu- 

 ally tapering, often corticated, cells of the larger branches 35-50// broad, as 

 long to one-half as long as the diameter; plurilocular sporangia narrowly 

 lanceolate and subulate to ovate and acute, sessile to short or long stalked ; 

 unilocular sporangia ovate, globose, or elliptical. 



Of this variable, cosmopolitan species two forms have 

 been collected on the Pacific coast. 



19. Ectocarpus confervoides pygmaeus {Aresch.) Kjellm. 



Plate XV, Figs. 5-9. 



Ectocarpus confervoides pygmceus (Aresch.) Kjellm., Handbk. I, 1890, 76. 



Erect filaments arising from a compact substratum of short creeping fila- 

 ments, unbranched or bearing above a few divergent, long branches, in fig- 

 ures i2-25,a in diameter, not at all narrowed above ; cells at base 2-3 times 

 as long as the diameter, above once to one-half as long ; chromatophores 

 large, irregular, band-form, few in each cell ; plurilocular sporangia lateral 

 and terminal, sessile or short stalked, lanceolate or conical, rather obtuse at 

 the apex, 6o-ioo,a x 20-30/^ ; unilocular sporangia lateral, abundant, ovate or 

 globose, 25-40/ji broad, often two to many seriate. 



Forming an olive-brown, velvety covering on Desniarestta 

 ligidata and Dictyoneuron Calif or niciim. Pacific Grove, 

 California. 



