Smith—Monograph of Scenedesmus. 
473 
“Var. cum apiculo ad fmem liberum utraeque cellulae. 
Long. cell. (Cum apice) 7.5-9.5 g; lat, cell. 5-5.5 g.” 
This variety has been found in England (West and West, 
1894, 1897B) and Ireland (West and West, 1902B). 
26. S. quadricauda (Turp.) de Breb. (PI. XXVII: Fig. 
39; PI. XXXI: Figs. 172-175; PI. XXXII: Fig. 176.) 
de Brebisson, 1835, p. 66. Meneghini, 1840, p. 206. Balfs, 
1848, p. 190; PI. XXXI, Figs. 12A-12F. Bailey, 1851, p. 29. 
Griffith and Henfrey, 1856, p. 565; PI. X, Fig. 50. Archer, 1857, 
p. 40. Babenhorst, 1868, p. 65; Figs. 34G-34H. Hohenbiihel- 
Heufler, 1871, p. 318. Olney, 1872, p. 135. Wittrock, 1872, p. 
31. Archer, 1874, p. 329. Nordstedt, 1877, p. 15. Wille, 1879, 
p. 30. Vorce, 1881, p. 59; PI. VII, Fig. 136. Cooke, 1882, p. 34; 
PI. XIII, Fig. 8. Nordstedt, 1882, p. 46. Spencer, 1882, p. 296; 
PI. XXIII, Fig. 11. Acheson, 1883, p. 418. Griffith and Henfrey, 
1883, p. 679, PI. XIV, Fig. 50. Martel, 1884, p. 188. Schaar- 
schmidt, 1884, p. 249. Wille, 1884, pp. 30, 45. Boldt, 1885, p. 
97. Cooke, 1885. Paque, 1885, p. 52. de Wildemann, 1885, p. 
123. Bennett, 1886, p. 3. Campbell, 1886, p. 93. Hansgirg, 
1886, p. 115; Fig. 62. Parfitt, 1886, p. 392. de Toni et Levi, 
1886, p. 67. Beck, 1887, p. 274. Bennett, 1887, p. 9. Jones, 
1887, p. 115. Lagerheim, 1887, p. 194. Martel, 1887A, p. 340. 
Martel, 1887B, p. 11. de Toni et Levi, 1887, p. 1584. Balsamo, 
1888, p. 40. Konig, 1888, p. 89. Nordstedt, 1888, p. 19. Hans¬ 
girg, 1889, p. 132. de Toni, 1889B, p. 565. W. West, 1889A, p. 
290. de Wildemann, 1889, p. 8. Andersson, 1890, p. 5. Hansgirg, 
1890A, p. 112. Boy, 1890, p. 338. W. West, 1890, p. 298. de 
Wildemann, 1890A, p. 137. de Wildemann, 1890B, p. 155. Borge, 
1891, p. 6. Hansgirg, 1891, p. 317. lanouchkievitch, 1891, p. 
290. de Toni, 1891, p. 272. W. West, 1891A, p. 248. W. West, 
1891B, p. 421. Hansgirg, 1892B, p. 119. Mobius, 1892, p. 435. 
de Toni, 1892, p. 108. Turner, 1892, p. 161. W. West, 1892A, 
p. 193. W. West, 1892B, p. 738. Lagerheim, 1893, p. 158. 
Schmidle, 1893A, p. 13. Borge, 1894, p. 9. Schmidle, 1894, p. 43; 
Tilden, 1894, p. 27. Borge, 1895, p. 7. West and West, 1895, 
p. 83; PI. V, Figs. 4-5. Boergesen, 1896, p. 36. Borge, 1896, p. 7. 
Lemmermann, 1896, p. 108. West and West, 1896, p. 381. 
Zacharias, 1896, p. 75. Chodat, 1897, p. 291. Farlow in Trelease, 
1897, p. 196. Gutwinski, 1897A, p. 3. Pitard, 1897, p. 516. 
Schmula, 1897, p. 35. Schroder, 1897A, p. 372. Schroder, 1897B, 
p. 487. Schroder, 1897C, p. 45. West and West, 1897B, p. 500. 
Chodat, 1898, pp. 166, 175. Forti, 1898, p. 118. Lemmermann, 
1898C, p.249. Mez, 1898, p. 149; PI. IV, Fig. 167. Nitardy, 1898, 
p. 104. Schorler, 1898, p. 38. Zacharias, 1898, p. 93. Boergesen, 
1899A, p. 135. Boergesen, 1899B, p. 333. Borge, 1899, p. 8. 
Forti, 1899, p. 89. Garbini, 1899A, p. 15. Garbini, 1899B, p. 
275. Iwanoff, 1899, p. 379. Lemmermann, 1899, p. 113. Le- 
