436 Universitii of California Puhlications in Botany [Vol. 8 



28. Ectocarpns ellipticus Saunders 



Fronds minute, about 1 mm. high, tufted, attached by numerous, 

 colorless, branched rhizoidal filaments ; erect filaments sparingly 

 dichotomous at the base, unbranched or with few unicellular branches 

 above, gradually attenuated upward, pilif erous ; cells 9-1 2/x diam. 

 and 1-2 times as long as the diameter at the base of the filaments, 3 

 times as long above ; ' * chromatophores thin branched bands, oval, ' ' 

 numerous ; zoosporangia sessile, ovate or ellipsoidal, 30-40/a long, 

 12-18/A broad ; gametangia cylindrical to blunt-conical, 75-100;U, (up 

 to 180/x.) long, 18-25ju, diam., borne laterally at or near the base of the 

 erect filaments, or occasionally arising directly from the creeping 

 filaments, sessile or on short pedicels below ; loculi one to few seriate. 



Growing in the conceptacles and cryptostomata of Fucus sp. 

 Pacific Grove, California. 



Saunders, Phyc. Mem., 1898, p. 149, pi. 14, figs. 6-9; Collins, 

 Holden and Setchell, Phyc. Bor.-Amer. (Exsicc), no. 527. 



Ectocarpus ellipticus is a curiously localized species growing upon 

 the inner margins of the openings of the cryptostomata and con- 

 ceptacles of Fucus at Pacific Grove, California. Transverse sections 

 of the fronds of the Fucus show that this Ectocarpus simply forms a 

 ring of growth just within the outer opening of the cryptostomata and 

 conceptacles just outside the hair-forming tissues. The rhizoidal fila- 

 ments of the Ectocarpus penetrate into the apparently looser tissues of 

 the ostiole of the ca^aties it inliabits. The gametangia are all basal or 

 borne near the bases of the erect filaments. It seems to be a very 

 distinct species. 



29. Ectocarpus chitonicola Saunders 



Fronds small, 1-2 mm. high, tufted, creeping filaments numerous, 

 irregular, branched ; cells of the creeping filaments ll-15|ii diam., 1-2 

 times as long as the diameter; erect filaments mostly simple, 14/x diam. 

 at the base, somewhat narrower above, with cells 0.5-2 times as long 

 as the diameter below, 2-3 times as long above, not constricted at the 

 partitions ; chromatophores small oval disks, numerous ; zoosporangia 

 unknown ; gametangia subcylindrical to narrowly ovoid, obtuse at the 

 apices, 90-175/x (up to 250/^,) long, 25-35|U, diam., borne laterally on 

 the erect filaments, or occasionally on the creeping filaments, the 

 lower gametangia on pedicels, the upper sessile. 



