1925] Setchell-Gardner: MeJanophyceae 411 



ovoid or curved, often ending in a longer or shorter hair, 500-600|U, 

 long- and 12-25/,i broad, seldom sessile, usually short pedicelled. 



Growing in quiet pools attached to other algae. San Francisco 

 Bay, California. 



Lyngbye, Hydrophyt. Dan., 181!), p. 131 (in part, as to pi. 43, 

 fig. C); Kjellman, Handb., I, 1890, p. 78; Kuckuck, Beitr. Kennt. 

 Ectocarp. Art., 1891, p. 65; Collins, Holden and Setchell, Phyc. Bor.- 

 Amer. (Exsicc), no. 2294. Conferva silicidosa Dillwyn, Brit. Conf., 

 1809, p. 69, pi. E (excl. synonym). 



We have followed Kjellman and Kuckuck in keeping Ectocarpus 

 siliculosus distinct from E. confervoides and in laying emphasis upon 

 the presence of elongated slender gametangia, some of which are 

 piliferous, as its chief characteristic. We know full well from our 

 own experience that it is difficult to draw a satisfactory line of 

 demarcation between the two species, but feel that the best we can 

 do is to keep tlieni distinct and draw the line somewhat arbitrarily. 

 The existence of such forms as Ectocarpus confervoides f. parvus 

 (Saunders) S. and G. indicates that there are perplexing forms whose 

 relationships and origins are perhaps impossible to formulate, but 

 otherwise, so far as the plants of our coast thus far discovered are 

 concerned, there seems little doubt that they conform to the original 

 idea of E. siliculosus. 



The plants distributed in the Phycotheca Boreali-Americana 

 (Joe. cit.) are the only characteristic plants of the species known on 

 our coast. These were taken from a quiet pool in a salt marsh on 

 Bay Farm Island, Alameda, California. 



Ectocarpus siliculosus f. subulatus (Kuetz.) S. and G. 



Fronds 5-25 cm. high, light yellow, fleecy, much branched, not 

 constricted at the joints; branches long, attenuated above, many end- 

 ing in a long hair ; cells of the main filaments 30-36ja broad, 1-1.25 

 times as long as broad ; zoosporangia unknown ; gametangia elongated 

 subulate-ovoid, some stouter, some more slender, 200-600/^ long, 12-48/x 

 broad, the upper (and as a rule more slender) usually terminating 

 in a hair, on a 2-10 (or 12) celled pedicel. 



In brackish pools, on sticks or grasses. Central California (San 

 Francisco Bay). 



Setchell and Gardner, Phyc. Cont. VI, 1922, p. 416. Ectocarpus 

 confervoides f. suhulatm Collins, Holden and Setchell, Phyc. Bor.- 

 Amer. (Exsicc), no. 1231. Ectocarpus subulatus Kuetzing, Actien, 



