458 Wisconsin Academy of Sciences , Arts , and Letters. 
1907, p. 657; PL XXXV (L), Fig. 2. Selk, 1907, pp. 5, 76. Gut- 
winski, 1909, p. 435. Brunnthaler, 1913, pp. 168, 171; Fig. 12. 
Chodat, 1913, p. 23. 
S. costatus forma typicus. Schroder, 1898, p. 24. 
“Cellulae adultae ellipticae vel semiovato-ellipticae et 
margine interiori leviter convexae, exteriori fere semicir- 
culares, utroque polo ad apices liberos tuberculo ornatae, 
plerumque quaternae (raro octonae) in coenobium solide 
concretae, membrana crassa longitudinaliter costata, qua 
de cause cellulae e vertice visae rotundae margine exteriori 
4-6-ies evidentur undulatae sunt. 
“Cellulae (adultae) 8-12 y latae. 20-22 y longae cum 
tuberculis coenobium (quadricellulare) 35-24 aut 33-35 y” 
GEOGRAPHICAL DISTRIBUTION 
EUROPE. Austria-Hungary (Gutwinski, 1909). England (G. 
S. West, 1904B; West and West, 1901B). Germany (Lemmer- 
mann, 1902; Schmidle, 1900A; Schroder, 1898; Selk, 1907). 
Sweden (Borge, 1907A). Switzerland (Chodat, 1902; Dalla Torre 
und von Sarnthein, 1901; Schmidle, 1895). 
AFRICA. Azores (Bohlin, 1902). 
Var. sudeticus Lemm. 
Lemmermann, 1896, p. 108. Lemmermann, 1898G, p. 249. 
Schroder, 1898, p. 24. Schmidle, 1900A, p. (111). Migula, 1907, 
p. 657. Brunnthaler, 1913, pp. 168, 171. 
S. denticulatus forma Wildemanii . Schroder, 1898, p. 24. 
“Cellulae 7-8 y latae, 13-15 y longae; coenobia plerumque 
quadricellularia circa 21 y lata, 26 y longa.” 
GEOGRAPHICAL DISTRIBUTION 
Germany (Lemmermann, 1896, 1898C; Migula, 1907; Schmidle, 
1900A; Schroder, 1898). 
16. S. brasiliensis Bohlin. (PI. XXVI: Figs. 30—31.) 
Bohlin, 1897, p. 22; PI. I, Figs. 36-37. Lemmermann, 1899, p. 
113. Marsson, 1899, p. 172. Lemmermann, 1900A, p. 98. 
Schmidle, 1900, p. (111). Lemmermann, 1901B, p. 80. Bohlin, 
1902, p. 44. Lemmermann, 1902, p. (251). Snow, 1903, p. 391. 
Volk, 1903, p. 103. Lemmermann, 1907A, p. 267. Lemmermann, 
1907B, p. 412. Schorler, 1907, p. 356. Lemmermann, 1908C, p. 
