Smith—Monograph of Scenedesmus. 
447 
Var. minor (Hansg.) nov. comb. 
S. bijugatus var. minor. Hansgirg, 1886, p. 115. de Toni, 
1889B, p. 564. Blumentritt, 1902, p. 86. Hansgirg, 1905, p. 
457. Migula, 1907, p. 658. 
£. bijugatus forma minor. Pascher, 1903, p. 175. 
S. obtusus var. minor. Yolk, 1903, p. 103. 
Coenobiis 8-cellularum, 40-45x 18 p; cellulis ellipticis 
vel ovoidis, 10-12 x 6-9 p; ceterum lit in var alternanti. 
The cultural work of Chodat has shown that varieties 
may be distinguished in S. bijuga on the basis of cell size. 
GEOGRAPHICAL DISTRIBUTION 
Austria-Hungary (Hansgirg, 1886, 1905; Migula, 1907; Pascher, 
1903). Germany (Yolk, 1903). Switzerland (Blumentritt, 1902). 
Var. obtusiusculus (Chodat) nov. comb. 
S. obtusiusculus Chodat, 1913, p. 47; Figs. 24-34. 
Dimens. cell. 7-5 p, 6-3 g. 
Var. alternans (Reinsch) Borge. (PI. XXV: Figs. 14-15.) 
Borge, 1907A, p. 57. Collins, 1909, p. 168. Borge, 1913, p. 60. 
S. alternans. Reinsch, 1866, p. 135; PI. XX, Fig. D5. Reinsch, 
1867, p. 81; PI. VI, Fig. 3. Lagerheim, 1883, p. 65. Lagerheim, 
1883B, p. 70. Lagerheim, 1887, p. 194. W. West, 1892A, p. 193. 
W. West, 1892B, p. 738. West and West, 1897B, p. 500. G. S. 
West, 1899, p. 221. Balsamo, 1900, p. 266. West and West, 
1902B, p. 63. Snow, 1903, p. 391. W. West, 1903, p. 100. Adams, 
1908, p. 35. 
S. bijugatus var. alternans. Hansgirg, 1886, p. 114. de Toni, 
1889B, p. 6. Lemmermann, 1893, p. 523. Schmidle, 1894, p. 43. 
Borge, 1895, p. 6. Bohlin, 1897, p. 22. Lemmermann, 1899, p. 112. 
Dalla Torre und von Sarnthein, 1901, p. 35. Chodat, 1902, p. 212. 
Bohlin, 1902, p. 43. Schmidle, 1903, p. 80. Lemmermann, 1904A, 
p. 39. Schmidle, 1904, pp. 4, 30, 32. Schmidle, 1904B, p. 7. 
Hansgirg, 1905, p. 457. Huber, 1905, p. 57. Volk, 1905, p. 64. 
Migula, 1907, p. 658; PI. XXXV (K), Fig. 8. Huber, 1908, p. 313. 
Marsson, 1911, p. 263. Brunnthaler, 1913, pp. 169, 172; Fig. 25. 
Selenastrum alternans. Weiss, 1892, p. 37. 
S. bijugatus forma alternans. Pascher, 1903, p. 175. 
S. obtusus var. alternans. Volk, 1903, p. 103. Reinhardt, 1905, 
p. 26. 
“Cellulae omnes aequales late ellipticae usque ovato- 
ellipticae, cellularum poli rotundati, cellularum diameter 
8 
