TIIK GREEN ALGAE OF NORTH AMERICA 117 



chromatophore single, slender and loose, with large pyreuoids, 

 making 3/2-6 turns in the cell ; fertile cells not swollen, or only 

 enough to contain the spores, which are ovoid, 1)^-2 diam. 

 long, diam. 26-30^. Mass., N. Y., N. J., Pa. Jturope. 



From ^. Grei'Ulcana, which this species considerably re- 

 sembles, it is distinguished by never having more than one 

 spiral, and by cells little if at all swollen. 



33. S. GREVILLEANA (Hass.) Kiitzing, 1849, p. 438; Petit, 

 1880, p. 10, PI. II, figs. 1-5 ; Wolle, 1887, p. 209, PI. CXXXII, 

 figs. 12-13; P. B.-A., No. 362. Filaments 28-33 f 1 diam., cells 

 3-10 diam. long ; chromatophore broad, usually single but 

 occasionally two in scattered cells, making 4-5, sometimes 6-9 

 turns in the cell ; fertile cells much swollen ; spores ovoid with 

 rounded ends, yellowish at maturity, 2-2^ diam. long, diam. 

 30-36 /A. Mass., N. J., Iowa. Europe. 



Often forming extensive masses, of a bright green color and 

 lubricous. To be distinguished carefully from 5". Weberi, as 

 noted under that species. 



34. S. GROENLANDICA Rosenviiige, 1883, p. 37, PI. VII. 

 Filaments 18-23 /u, diam., cells 18-28 diam. long; chromato- 

 phore single, making 3-8 turns in the cell ; fertile cells swollen 

 in the middle, the swollen part cylindrical or sub-cylindrical, 

 one-third to one-fourth the total cell length ; spores ellipsoid, 

 34-38X100-130 p., dark brown; conjugation lateral; partheno- 

 spores occurring in unswollen cells, the spores elongate, but of 

 more or less irregular form, nearly as large in diam. as the cell. 

 Greenland, Mass. 



Resembling somewhat 6*. quadrata and .5". Spreeiana ; from the 

 former it differs by the much longer cells, the swelling occupy- 

 ing only a small part of the whole length ; from the latter by the 

 swelling being sharply marked off from the unswollen part of the 

 cell, and also by the color of the spore, dark brown at maturity 

 instead of yellow. 



35. S. HASSALLII (Jenner) Petit, 1880, p. 12, PI. II, figs. 

 6-8; Wolle, 1887, p. 210, PI. CXXXIII, figs. 5-7; Phyk. 

 Univ., No. 732. Filaments 30-35 /* diam., cells 4-8 diam. long ; 

 chromatophores 2, quite broad and loose, making 1^-2 turns in 

 the cell; fertile cells slightly swollen; spores ellipsoid, 1^-3 

 diam. long, diam. 42-48 p., yellow at maturity. Mass., low^a. 



Europe. 



36. S. INSIGNIS (Hass.) Kiitzing, 1849, p. 438; Petit, 1880, 

 p. 13, PI. Ill, figs i & 2; Wolle, 1887, p. 210, PI. CXXXIII, 



