wall smooth; 31.4-41/* in diameter, 30-32-(41)/a long. Antheiidia 

 10-11-(15) jjL in diameter, 5-6-(7)/i, long. 

 In small ponrls. Mich., Wis. 



Oedogonium Vaucherii (Le CI.) A. Braun 1855, p. 40 



PI. 43, Fig. 20 

 Macrandrous; monoecious. Vegetative cells cylindric, 20-30/a in 

 diameter, 32-1 18/i long, Oogonia solitary; ovoid; opening by a 

 superior pore; 40-58/a in diameter, 45-65/i, long. Oospores globose 

 or subglobose; not filling the oogonia; wall thick and smooth; 35-45/x 

 in diameter, 35-55/i, long. Antheridia 17-30/x, in diameter, 6-15/j. long. 

 Mich. 



Oedogonium vulgare (Wittr. ) Tiffany 1934, p. 324 



Macrandrous; monoecious. Vegetative cells cylindric, 5-8fx in 

 diameter, 15-48/x long. Oogonia 1-5; subdepressed-ovoid-globose or 

 subdepressed-globose; opening by a median pore; 18-25/i. in diame- 

 ter, 18-26/x long. Oospores subdepressed-globose; filling the oogonia; 

 wall smooth; 16-23/t in diameter, 15-19/a long. Antheridia 5-7 /x in 

 diameter, 9-12/a long. 



Mich. „ _ 



Section 3 



Macrandrous — Dioecious — Operculate 



Oedogonium abbreviatum (Hirn) Tiffany 1934, p. 325 

 PL 36, Figs. 15, 16 



Macrandrous; dioecious. Vegetative cells short-cylindric, forming 

 rather stout plants; (10)-18-22/x in diameter, (15)-37-50/a long. 

 Oogonia solitary, sometimes 2 together; ovoid-globose or subglobose; 

 operculate; division superior; ( 28 ) -37-40/x. in diameter, (30)-38-48/i 

 long. Oospores subglobose; wall smooth; (26)-27-33-(34)/x in 

 diameter, (26) -27-34— (37) /a long. Antheridia (not observed in our 

 collections) 9-16//, in diameter, 5-10/* long. 



In backwash pools on beach; attached to moss in shallow water. 

 Wis. 



Oedogonium calvum Wittrock 1875, p. 37 

 PI. 37, Figs. 15, 16 



Macrandrous; dioecious. Vegetative cells capitellate; 7.4-8.5/x in 

 diameter, 26-28- (40)/* long; basal cell much elongated. Oogonia 

 solitary or as many as 4 in a series; globose or depressed-globose; 

 operculate; division median; (25.9) -27- (30)/* in diameter, (22.2)- 

 25-30-(40)/* long. Oospores globose or depressed-globose; filling 

 the oogonia or nearly so; wall smooth; 22.2/* in diameter, 19-22/* 

 long. Antheridia not observed. 



[182] 



