Oospores ellipsoid, nearly filling the oogonia; wall smooth; 15-17|U, 

 in diameter, 17-20)U, long. Antheridia 4-5/x in diameter, 5-6/a long. 

 Mich. 



Oedogonium macrandrium Wittrock 1871, p. 130 



Nannandrous; gynandrosporous; operculate. Described in the fol- 

 lowing section. 



Oedogonium megaporum Wittrock 1872, p. 3 



Nannandrous; idioandrosporous. Vegetative cells cylindric, 13-17/i, 

 in diameter, 40-100/* long. Oogonia 1-6; pyriform, with 12-16 

 longitudinal ribs; operculate; division supramedian; 37-42/x in 

 diameter, 40-45/i. long. Oospores subdepressed-globose; not filling 

 the oogonia; wall smooth; 31-35- ( 38 )/x in diameter, 27-30/x long. 

 Dwarf male plants unicellular, 8-12yu, in diameter, 13-16/* long. 



Mich, 



Oedogonium polyandrium Prescott 1944, p. 355 

 PI. 42, Figs. 7-9 



Nannandrous; idioandrosporous (?). Vegetative cells slightly 

 capitellate, 4.5-5.4/* in diameter, 14-30/i long. Oogonia solitary; 

 ovate or broadly ellipsoid; operculate; opening superior; 17-19/* in 

 diameter, 27-28/i long. Oospores ovate; nearly filling the oogonia; 

 outer spore wall with coarse sparsely arranged scrobiculations or 

 shallow pits; middle and inner layers of the spore wall smooth; 

 15-17/* in diameter, 22-25/t long. Dwarf male plants 2-celled, 

 numerous; on the oogonia; stipe 4.5/i in diameter, 14-16/* long. 

 Antheridia exterior ( ? ) , 



This species has a combination of characteristics which make it 

 quite unlike any other. It should be compared, however, with Oe. 

 longatum, which is similar in size, but in which the outer layer of 

 the oospore wall is smooth. Also in Oe. longatum the dwarf male 

 plants are distinctly curved or reflexed. Skuja ( 1932, p. 59 ) describes 

 the oospore wall as having the middle layer pitted. 



Attached to grass in a bog. Wis. 



Oedogonium pseudoplenum TiflFany 1934, p. 326 

 PI. 40, Fig. 9 

 Nannandrous; idioandrosporous. Vegetative cells capitellate, (12)- 

 15.6-16.5- (17)/* in diameter, (36)-54.6-120/t long. Oogonia 1-8; 

 globose; operculate; division median and wide; 36-40-(42)/* in 

 diameter, (36) -39-41- (53)/* long. Oospores depressed-globose; not 

 filling the oogonia; wall smooth; (30) -31.2-33/* in diameter, (27)- 

 30-31/* long. Dwarf male plants unicellular; on the oogonia; 8/* in 

 diameter, (12) -14-15/1 long. 

 In a Sphagnum bog. Wis. 



[202 1 



