ovoid; filling the oogonia; wall smooth; 51-60;a in diameter, 63-80/a 

 long. Antheridia 28-35/a in diameter, 7-17/a long. 

 Mich. 



Oedogonium moniliforme Wittrock 1875, p. 40 



Macrandrous; dioecious. Vegetative cells cylindric, 9-13ju in 

 diameter, 30-72/i, long. Oogonia 1-5; pyriform or somev^^hat ovoid- 

 globose; opening by a supramedian to nearly superior pore; 23-33/i. 

 in diameter, 28-42/a long. Oospores globose or depressed-globose; 

 not filling the oogonia; outer wall smooth, median wall scrobiculate; 

 22-32/x in diameter, 22-32|a long. Antheridia 10-12/x in diameter, 

 8-13;u, long. 



Oedogonium orientale Jao 1934, p. 85 

 PI. 41, Figs. 8,9 



Macrandrous; dioecious. Vegetative cells cylindric, 12-15)m in 

 diameter, 55-66/;, long. Oogonia solitary; oblong-ellipsoid; opening 

 by a superior pore; S8-42ti in diameter, 79-82/t long. Oospores 

 ellipsoid to oblong; filling the oogonia laterally but not longitudin- 

 ally; outer spore wall smooth, middle wall layer with about 18 

 longitudinal ribs which are entire and continuous; 32-34/» in 

 diameter, 54-56/a long. Antheridia (not observed in our collections) 

 11-14/x in diameter, 8-17/1, long. 



Our specimens lack the terminal, hyahne seta described for Oe. 

 orientale. They are tentatively assigned to this species, however, 

 on the basis of oospore characters and size. The discovery of the 

 male filaments might make it necessary to describe our specimens 

 as a new species. 



Attached to submerged grass. Wis. 



Oedogonium plagiostomum Wittrock 1875, p. 41 

 PI 32, Figs. 3, 4 

 Macrandrous; dioecious. Vegetative cells cylindric, rather stout, 

 (18.5) -22-25- (27) /A in diameter. Oogonia solitary; ovate-globose; 

 opening by a superior pore; (38)-42-49/x in diameter, (44.4)-60-65/x 

 long. Oospores globose; wall thick, smooth; (35)-41-47/i in diameter. 

 Antheridia 20-24/x in diameter, 8-12/x long. 



Attached to overhanging grass in small lake. Wis. 



Oedogonium princeps ( Hass. ) Wittrock 1875, p. 42 



PI. 43, Figs. 16, 17 



Macrandrous; dioecious. Vegetative cells cylindric, 33-43/x in 



diameter, 40-155/x long. Oogonia solitary; subobovoid; Httle wider 



than the vegetative cells; opening by a sup'^rior pore; 57-63/t in 



[ 173 1 



