Section 8 

 Nannandrous — Idioandrosporous — Operculate 



Oedogonium Ackleyae Tiffany 1937, p. 70 

 Nannandrous; idioandrosporous (?). Vegetative cells cylindric, 

 9-lllx in diameter, 27-60jii long. Oogonia 1-3; globose or subglobose; 

 operculate; division superior; 32-35ju, in diameter, 30-35ju, long. 

 Oospores globose; not filling the oogonia; median wall scrobicuiate; 

 31-33ju in diameter, 31-32/x long. Antheridia 8-9/x in diameter, 

 6-10/x long. 



Oedogonium brasiliense Borge 1899, p. 4 

 PL 41, Figs. 3, 4 



Nannandrous; idioandrosporous. Vegetative cells distinctly capi- 

 tellate, (16)-20.3-22/x in diameter, (35)-55-74-(95)/a long. Oogonia 

 1_4_(9); depressed-globose; operculate; division wide, median or 

 supramedian; 51. 8-55.5- ( 63 )/i in diameter, 46.2-52- ( 59 )/li long. 

 Oospores globose or depressed-globose; not filling the oogonia; wall 

 smooth; (44.5)-48-53/x in diameter, 33-35- ( 45 )/x long. Dwarf male 

 plants unicellular; on the oogonia; llju in diameter, 12-13-(19)/x long. 



Our specimens differ from the original description of Oe. brasilien- 

 se in having the operculum sometimes supramedian and in having 

 the oogonia in longer series. 



In a small pond on grass. Wis. 



Oedogonium Kozminskii Prescott 1944, p. 355 

 PI. 42, Figs. 4-6 



Nannandrous; idioandrosporous. Vegetative cells cylindric to 

 shghtly capitellate, 14-15.6/x in diameter, 50-60/x long. Oogonia 

 solitary; globose; operculate; division supramedian; (46)-50.7-52/i, 

 in diameter, 46-53.7/a long. Oospores globose or depressed-globose; 

 wall smooth; 43.9-45|la in diameter, 39-42/^ long. Suffultory cell not 

 enlarged or scarcely so. Dwarf male plants unicellular; on the 

 oogonia; 11.7-13fi in diameter, 13-14.5/x long. 



The distinguishing characteristics of this species are the capitellate 

 vegetative cells and the supramedian opening of the oogonium. It 

 should be compared with Oe. mirandrium Skuja, in which the 

 suffultory cell is enlarged and the oogonium smaller. 



Attached to grass in a Sphagnum bog. Wis. 



Oedogonium longatum Kuetzing 1853, Tab. Phyc. 3, p. 11 

 Nannandrous; idioandrosporous (?). Vegetative cells cylindric, 

 4r-7fi in diameter, 10-35/^ long. Oogonia 1-3; ovate or ellipsoid; 

 operculate; division superior; 16-18(a in diameter, 21-25/a long. 



[201] 



