446 University of California Publications in Botany [Vol. 8 



6. Streblonema penetrale S. and G. 



Fronds forming a continuous pulvinate stratum of indefinite shape 

 and size on the stipe of the host ; penetrating portion composed of 

 sparingly branched filaments extending relatively deep into the host 

 and mostly perpendicular to its surface; erect filaments fasciculately 

 branched at the surface of the host, 70-125/x long, tapering slightly 

 upwards, not piliferous; cells of the penetrating filaments cylindrical 

 to irregular, 6.5-8ju diam., 3-5 times as long; cells of the erect filaments 

 cylindrical to slightly doliif orm ; 6.5-8ju, diam., 1.5-2.5 times as long ; 

 chromatophores band-shaped ; zoosporangia unknown ; gametangia 

 cylindrical to blunt-fusiform, more or less irregular, 30-40;a long, 

 8-1 1/i broad ; loculi uniseriate. 



Growing on the stipes of H esperophycus Harveyanus. Pacific 

 Grove, California. 



Setchell and Gardner, Phyc. Cont. V, 1922, p. 388, pi. 44, figs. 3, 4. 



Streblonema penetrale, like S. myrionematoides below, is a difficult 

 species to classify. In its method of development and general struc- 

 ture it approximates S. myrionematoides closely. The penetrating 

 portion is much more highly developed than in that species, extending 

 into the host among the cells to a depth of four or five times as great 

 as the part which extends beyond the surface. The size of all the 

 parts is, in general, greater than in S. myrionematoides. No horizontal 

 filaments are present. The penetrating filaments are mostly per- 

 pendicular to the surface. 



7. Streblonema transfixum S. and G. 



Fronds forming patches 5-8 mm. diam. ; creeping filaments pene- 

 trating deeply among the cells of the host, distorted, irregularly 

 branched, 4—ojx diam., giving rise to scattered, short, erect, unbranched 

 filaments protruding from the surface and mostly terminated by game- 

 tangia; cells of the erect filaments cylindrical, 7-9/a diam., 0.75-1.5 

 times as long ; chromatophores band-shaped, nearly covering the cell 

 wall ; zoosporangia unknown ; gametangia cylindrico-conical, blunt, 

 40-60ju, long, 8-12/A broad ; loculi 1-2 seriate. 



Growing on Desmarestia herbacea. San Pedro, California. 



Setchell and Gardner, Phyc. Cont. V, 1922, p. 391. 



Streblonema transfixum forms definite, discolored areas on the 

 surface of the host, readily detectable. The species was described from 



