THE GREEN ALGAE OF NORTH AMERICA 167 



10. SCHIZOCHLAMYS A. Braun in Kiitzing, 1849, p. 891. 



Cells spherical or ellipsoid, irregularly distributed through the 

 colorless gelatine, free floating or attached to water plants ; 

 chromatophore filling the cell, without pyrenoid ; cell dividing 

 into two daughter cells, the mother cell wall remaining in 2 or 4 

 pieces, about the new cells. Only one species. 



S. GELATINOSA A. Braun in Kiitzing, 1849, p. 891 ; 1856, 

 PI. LJI ; P. B.-A., No. 369. Forming an irregular mass, up to 

 10 cm. long, pale or yellowish green ; cells globose or ellipsoid, 

 11-14 P- wide, sometimes arranged by 2 or 4. Fig. 50. Me., 

 Mass., Alaska, Cal. Europe. 



Much like a Tctraspora, but not membranaceous, and distin- 

 guished by the persistent pieces of the mother cell wall, several 

 generations of which may be found enclosed within the oldest. 



ii. ELAKATOTHRIX Wille, 1898, p. 302. 



Cells ovoid or fusiform, with parietal chromatophore covering 

 all the wall except at the ends, with a large pyrenoid ; in a gen- 

 eral gelatinous sheath ; cell dividing by a cross wall, the daugh- 

 ter cells maintaining a longitudinal arrangement for a longer or 

 shorter time. 



E. AMERICANA Wille, 1899, p. 150; P. B.-A., No. 607; 

 Pusola viridis Snow, 1903, p. 389, PI. II, fig. VI. Cells ovoid 

 or fusiform, 12-25X6-15 /u,, dividing across the middle, the 

 daughter cells growing out obliquely, effacing the original lon- 

 gitudinal order ; the gelatinous sheath in the form of a laciniate, 

 anastomosing thallus, attached to various plants and reaching a 

 length of several cm.; later forming floating masses of indefi- 

 nite form. Fig. 51. Conn., L,ake Erie. 



12. HORMOTILA Borzi, 1883, p. 99. 



Cells spherical, ovoid or ellipsoid, with one pyrenoid ; either 

 arranged 2-4-8-16 together in a wide, more or less firm, often 

 concentrically lamellate gelatinous mass, which may form a con- 

 siderably extended stratum ; or distributed at intervals along 

 colorless, branching, cylindrical, gelatinous bands. Asexual 

 reproduction by zoospores, formed in ovoid sporangia, much 

 larger than the vegetative cells ; zoospores 8 or more in a spor- 

 angium, ovoid or ovoid-oblong, with red stigma, and prolonged 

 to a point with two cilia ; escaping through a lateral opening. 

 Only one species. 



H. MUCIGENA Borzi, 1883, p. 99, Pis. VIII and IX; P. 

 B.-A., No. 1218. Cells 4-12 ju, diatn., sporangia to 3o / u,diam., 

 zoospores 3-5X1-2.5 ^ ; mass reddish or bluish. On woodwork, 

 etc., in standing fresh water. Fig. 52. Cal. Europe. 



