Smith—Monograph of Scenedesmus. 
465 
in seribus tribus longitudinaliter ordinatis. Long. cell. 20-21 
p; lat. cell. 6-6.5 /z.” 
Known only from England. 
23. S. serratus (Corda) Bohlin. (PI. XXVIII: Figs. 
55, 57.) 
Bohlin, 1902, p. 44; PL I, Fig. 2. Brunnthaler, 1913, pp. 166, 
171; Fig. 10. Ghodat, 1913, p. 25. 
Arthrodesmus serratus. Corda, 1839, p. 244; PI. VI, Fig. 35. 
Coenobia 4-cellularum. Cellulis oblongi-ovatis; mem- 
branae cellularum terminalum cum singula serie aculeorum 
parvorum ex polo ad polum; cellulis interioribus cum duabus 
seribus aculeorum; polis omnorum cellularum cum 3-4 denti- 
bus. Long. cell. 15-20 p; lat. cell. 4.5-7 p. 
Two colonies of this species have been found in material 
collected from the Yahara River above Lake Kegonsa (Wis¬ 
consin). The arrangement of the rows of spines on the sides 
of the cells (Fig. 57) and the teeth on the ends of the cells 
is the same as described by Bohlin, but the cells I have 
found are somewhat smaller being 10-12 by 3-3.5 p. 
The species has been found only in Austria (Corda), the 
Azores (Bohlin), and Wisconsin. 
24. S, abundans (Kirchner) Chodat. (PI. XXX: Figs. 
133-136; PI. XXXI: Figs. 137-140.) 
Ghodat, 1913, p. 77. 
S. caudatus forma abundans. Kirchner, 1878, p. 98. 
S. quadricaudatus var. (3. Ralfs, 1845, p. 402; PI. XII, Fig. 4B. 
Hassall, 1845, p. 392. Ralfs, 1846, p. 159; PI. XV, Fig. 4B. 
S. quadricauda var. (3. Ralfs, 1848, p. 190; PI. XXXI, Fig. 
12G. Balsamo, 1900, p. 266. 
Scenodesmus caudatus var. minor. Kiitzing, 1849, p. 186. 
Scenodesmus quadricauda var. (3 . Archer, 1861, p. 753; PI. I, 
Fig. 42. 
S. quadricauda forma abundans. Lagerheim, 1883, p. 64; PL II, 
Fig. 20. Marsson, 1901A, pp. 96, 106. Ghodat, 1902, p. 214. 
Pascher, 1903, p. 175. Collins, 1909, p. 169. 
S. quadricauda var. abundans. Hansgirg, 1886, p. 115. deToni, 
1889B, p. 566. Gutwinski, 1891, p. 302. W. West, 1892A, p. 194. 
West and West, 1895, p. 83. West and West, 1897B, p. 500. G. S. 
West, 1899, p. 221. Lagerheim, 1900, p. 10. West and West, 
1901A, p. 197. West and West, 1901B, p. 120. West and West, 
1902B, p. 64. Volk, 1903, p. 104. West and West, 1904, p. 531. 
Fink, 1905, p. 25. Hansgirg, 1905, p. 458. Huber, 1905, p. 57. 
