114 A CATALOG OF ILLINOIS ALGAE 



gan; Sag Bridge — swamp, Sept. 8, 1939, #984. Britton: Lake, 

 Antioch — channel between Grass Lake and Lake Marie, Sept. 

 14, 1939, #1029. Eddy 1931B, p. 461: Pulaski, Wetaug— sink- 

 hole ponds (July, Sept.). 



S. ARCUATUs var. platydisca G, M. Smith. Smith, loc. cit., p. 451. pi. 



25. f. 11 (1916). 



Scenedesmus platydisca (Smith) Chod. 



Ahlstrom 1936, p. 293, as S. platydisca; Britton: Cook, Evanston 

 — Lake Michigan; Palos Park — small shallow ponds, July 13, 

 Sept. 8, 1939, #535, 536, 978; Sag Bridge — stone-quarry pond, 

 Sept. 8, 1939, #1007; small pond and extensive swamp, Sept. 8, 

 1939, #1021. Britton: Lake, Fox Lake— in Fox Lake, Aug. 25, 

 1939, #951. 



S. ARMATUS (Chod.) G. M. Smith. Smith, loc. cit., p. 460. pi. 28-30. f. 



53, 90-93, 109, 110 (1916). 



Britton 1940, p. 71: Cook, Evanston — small pond in Calvary 

 Cemetery, June 23, 1938, #74; small greenhouse reservoir E. of 

 the North Shore Channel at Howard St., June 23, 1938, #75; 

 Morton Grove — small greenhouse reservoir and small pond 

 about 1 mile N.W., May 10, 1938, #42, 43. Lake, Highwood— 

 small pond, May 15, 1938, #73; Wauconda — Bangs Lake, Aug. 

 24, 1939, #925. 



S. BijUGA (Turp.) Lag. Smith, loc. cit., p. 441. pi. 25. f. 2 (1916). 

 Scenedesmus bijugatus (Turp.) Kuetz. 



Transeau 1913B, p. 80; 1916, p. 125: Coles, Charleston — ponds 

 (Apr., July). Kofoid 1908, p. 31, as 5. bijugatus: Mason, Havana 

 —Illinois River (May-Sept.). Eddy 1931B, p. 461: Pulaski, 

 Wetaug- — sink-hole pond (Sept., Dec). 



S. BIJUGA var. ALTERNANS (Reinsch) Borge. Smith, loc. cit., p. 447. f. 



14, 15 (1916). 



Transeau 1913B, p. 80; Coles, Charleston — ponds (Apr.-July). 



S. BRAsiLiENSis Bohlin. Smith, loc. cit., p. 458. pi. 26. f. 30, 31 (1916). 

 Britton: Cook, Palos Park — small shallow ponds, July 13, 1939, 

 #533, 534; Sag Bridge — small ponds and swamps, Sept. 8, 1939, 

 #988, 996, 1005, 1016, 1018; Schnells Corner— small ponds in 

 Elk Grove Forest Preserve, Aug. 8, 1939, #780, 785. Lake, Lake 

 Zurich— in Lake Zurich, Aug. 24, 1939, #917. McHenry, Mc- 

 Henry— swamp E. of McCullom Lake, July 6, 1939, #374, 376. 



S. CARINATUS (Lemm.) Chod. Smith, loc. cit., p. 462. pi. 26. f. 25 



(1916). 



Britton: McHenry, Ridgefield — pond about 1 mile N.W., July 7, 

 1939, #417, 418. 



S. DENTicuLATUs Lag. Smith, loc. cit., p. 452. pi. 26. f. 23 (1916). 

 Kofoid 1908, p. 31: Mason, Havana — Illinois River ("late sum- 

 mer — early autumn"). 



