Oedogonium fragile Wittiock 1871, p. 120 

 PL 32, Fig. 13 



Macrandrous; monoecious. Vegetative cells cylindiic, (12)-15- 

 18.5/x in diameter, 51.8-120/t long. Oogonia solitary; globose; opening 

 by a superior pore; (42)-44-50/x in diameter, 44-50- ( 55 )/* long. 

 Oospores globose; nearly filling the oogonia; wall smooth; 39-40- 

 (46) IX in diameter, (38)-39-40-(46)/. long. Antheridia 15-18/^ in 

 diameter, 4-9. 6/x long. 



This species should be compared with Oe. fennicum, from which 

 it differs but slightly. In the latter the vegetative cells are a little 

 larger and the oogonia smaller than in Oe. fragile. No specimens 

 of Oe. fragile were found with epigynous and hypogynous anther- 

 idia, a condition common in Oe. fennicum. 



Common in shallow water of several lakes and ponds. Mich., Wis. 



Oedogonium globosum Nordstedt 1878, p. 20 



PI. 31, Figs. 1-3 



Macrandrous; monoecious. Vegetative cells cylindric, 10.8-14ju, in 



diameter, (40)-75-(95)/i, long. Oogonia solitary; globose; opening 



by a superior pore; (32)-40/i, in diameter, (32)-40-46/x long. Oospores 



globose; wall thick, smooth; nearly filling the oogonia; (30)-38;a in 



diameter. Antheridial cells (9)-10-12|U in diameter, (4)-6-8/x long. 



Growing on submerged grass. Mich., Wis. 



Oedogonium Hirnii Gutwinsld 1896, p. 34 

 PI. 31, Fig. 4 

 Macrandrous; monoecious. Vegetative cells cylindric or slightly 

 capitellate, 8-ll-(13)(a in diameter, (28)-61-72-(80)/x long. Oogonia 

 solitary; subglobose or subovate; opening by a superior pore; 32-37/i, 

 in diameter, 32-39/t long. Oospores globose; wall thick, smooth; 

 (27)-28-(31)/x in diameter. Antheridial cells . (8)-10.8-( 11) /^ in 

 diameter, 5-7.2/x long. 



On submerged sticks and leaves. Wis. 



Oedogonium intermedium Wittrock in Wittrock & Nordstedt 1886, 



Algae Exsic. No. 708 

 PL 31, Figs. 5, 6 

 Macrandrous; monoecious; Vegetative cells cylindric, (15)-16.6- 

 17-(18)/x in diameter, (45)-59-66-(80)/x long. Oogonia solitary; 

 obovoid or obovoid-globose; opening by a superior pore; (31)-37-38/x 

 in diameter, (34)-40-42-(45)/x long. Oospores globose; nearly filling 

 the oogonia; wall smooth; (30)-33-36/x in diameter, 33-36-(41)/x 

 long; antheridia 14.8-16/x in diameter, 4-10/x long. 

 Pool in a gravel pit; in a roadside fosse. Wis. 



[178] 



