440 University of California Puhlications in Botany [Vol. 8 



34. Ectocarpus Bryantii S. and G. 



Fronds intertwined, forming a more or less continuous stratum, 

 1-2.5 mm. high, attached by relatively short, penetrating, rhizoidal 

 filaments ; erect filaments forked more or less at the surface of the 

 host, with very few short ramuli above, nearly cylindrical, tapering 

 slightly above, uncorticated ; terminal cell blunt, 28-32/x diam., cells 

 1-2 times as long as broad ; chromatophores small disks ; zoosporangia 

 unknown ; gametangia narrowly to broadly fusiform, sessile or on 

 1-celled pedicels, 70-lOOjU, (up to 140ja) long, 25-35/x. broad, scattered 

 promiscuously along the whole length of the erect fronds. 



Growing on Codium Brandegeei. La Paz, Lower California. 



Setchell and Gardner, Mar. Alg. Gulf of Calif., 1924, p. 720, pi. 17, 

 fig. 45. 



Ectocarpus Brya.ntii and E. gonodioides are evidently closely 

 related to each other and both have near affinities in the pusillus group 

 of Sauvageau (1895). They both differ from all of the forms pro- 

 posed in the method of branching and in having no hairs terminating 

 the erect filaments. 



5. Streblonema Derb. and Sol. 



Fronds composed of more or less branched, monosiphonous or in 

 part polysiphonous filaments, wholly or largely endophytic ; prostrate 

 primary filaments wholly endophytic, creeping among the cells of the 

 host, erect secondary filaments wholly or in large part endophytic, 

 simple or branched, hairs present or absent ; zoosporangia and g-ame- 

 tangia both present, terminal or lateral on the erect or on the prostrate 

 filaments, sessile or, more rarely, short-stalked. 



Derbes and Solier, in Castagne, Supplem. Catal. Marseille, 1851, 

 p. 100. 



The type species is >S^. sphaericum. 



Key to the Species 



1. Fronds causing noticeable distortions of the host 2 



1. Fronds not causing noticeable distortions 3 



2. Distortions in the form of pustules 13. S. scabiosum (p. 4.50) 



2. Distortions in the form of extended rugose areas ...12. S. rugosum (p. 449) 



3. Fronds producing noticeable patches or discolorations 4 



3. Fronds inconspicuous 11 



4. Patches large or extended 5 



4. Patches small, usually orbicular (0.5 cm. or less diam.) 6 



5. Patches orbicular 11. S. evagatum (p. 449) 



