102 A CATALOG OF ILLINOIS ALGAE 



(June). McHenry, Algonquin — Fox River ("summer"); Green- 

 wood— Nippersink Creek and Wonder Lake, Jul}^ 6, 1939, #365, 

 366, 368; Johnsburg— Fox River, July 25, 1939, #590; McHenry 

 — swamps and small stream at N.E. side of McCullom Lake, 

 July 6, 1939, #376, 377, 380, small pond about 3 miles N.W., 

 July 6, 1939, #390; Richmond — Twin Lakes (Lake Elizabeth), 

 Aug. 2, 1939, #729; Woodstock— swamp about 2 miles S.E., 

 July 7, 1939, #403. Menard, Petersburg — Sangamon River (June, 

 July, Sept.). Mercer, New Boston — Mississippi River (July- 

 Sept.), Edwards River (July). Monroe — Mississippi River 

 (June). Montgomery, Coffeen^ — ponds (May). Moultrie, Sullivan 

 ■ — artificial pond (Aug.). Ogle, Byron— slough (June-Aug.); 

 Grand Detour— slough (June-Aug.). Piatt, Monticello — Sanga- 

 mon River (June, Aug., Nov.). Pike — Mississippi River (June). 

 Pulaski — Mississippi and Ohio Rivers (June). Randolph — 

 Mississippi River (June). Rock Island — Mississippi River (July- 

 Sept.). Sangamon, Illiopolis, Riverton, Springfield — Sangamon 

 River (June, July, Sept.). St. Clair^ — Mississippi River (June). 

 Union — Mississippi River (June) ; Larue — Wolf Lake (June- 

 Aug.). Wabash, Mt. Carmel — Wabash River. Whiteside — 

 Mississippi River (June); Erie — Rock River Slough, Hatwood 

 Slough (June-Aug.). Will, Lockport^ — DesPlaines River (June- 

 Aug.). 



P. DUPLEX var. CLATHRATUM (A. Br.) Lag. Smith, Bull. Wis. Geol. & 



Nat. Hist. Surv. 57(1): 171. pi. 47. f. 1-3 (1920). 



Transeau 1913B, p. 81 : Coles, Charleston — ponds (May).Britton 

 Cook, Argonne Forest Preserve — Maple Lake, Sept. 8, 1939, #991. 

 Lake, Fox Lake — Fox Lake, south of Indian Point, Aug. 25, 

 1939, #950; Fox Lake— Grass Lake channel, Aug. 25, 1939, #948; 

 Libertyville— DesPlaines River at Route 59A, July 29, 1938, 

 #181. McHenry, McHenry— Nippersink Creek below Wonder 

 Lake dam, July 6, 1939, #365, 366. Transeau: Montgomery, 

 Coffeen — ponds (May). Moultrie, Sullivan^artificial pond 

 (Aug.). 



P. DUPLEX var. ROTUNDATUM Lucks. Tiffany, Contrib. Franz T. Stone 



Lab. 6: 50. pi. 8. f. 143 (1934). 



Britton: Cook, Northbrook — small pond in Somme Forest Pre- 

 serve, June 27, 1938, #112; Sag Bridge— pond, Sept. 8, 1939, 

 #1000. Lake, Fox Lak^Petite Lake, Aug. 25, 1939, #958, Lake 

 Marie, Sept. 14, 1939, #1030; Wauconda— Slocum Lake, Aug. 

 24, 1939, #926. 



P. INTEGRUM Naeg. Tiffany, loc. cit., p. 49. f. 145 (1934). 



Britton: Cook, Palos Park— swamp, July 14, 1939, #556. 



P. SIMPLEX Meyen. Tiffany, loc. cit., p. 50. f. 135-136 (1934). 



Galtsoff 1924, pp. 399, 402, 404: Carroll— Mississippi River 



