OEDOGONIUM 105 
87. Oe. quadratum Hallas. 
(Pl. XXXIV, figs. 306-308. ) 
1905, p. 405, fig. 12; Hirn 1906, p. 19, Pl. III, fig. 10. 
Monoecious; oogonium 1-4, angular-globose, operculate, division 
median; oospore angular-globose, filling oogonium, spore wall smooth; 
antheridium 1, alternating with vegetative cell; vegetative cell capitel- 
late; basal cell subhemispherical; vegetative cell 5-12 25-140y; 
oogonium 22-28 X 28-33"; oospore 20-26X26u; antheridium 10-12 
12—14u; basal cell 7-12 X 6-9un. 
Denmark. - 
Cf. Oe. capitellatum above. 
88. Oe. bohemicum Hirn. 
(Pl. XXXVI, fig. 344.) 
1900, p. 169, Pl. XXVII, fig. 154; Heering 1914, p. 216, fig. 327; Tiffany 1926, 
pelOle Plz PTI. fig. 30. 
Monoecious; oogonium 1, globose, operculate, division superior; 
oospore globose, filling oogonium, spore walls smooth; antheridium 
1-4, subepigynous; sperms 2, division horizontal; vegetative cell cap- 
itellate, 10-16X21-66u; oogonium 42-4546-49u; oospore 40-43 x 
40-43; antheridium 9-10 5-7. 
United States: Iowa; Austria. 
This is the largest of the monoecious species combining the 
median location of the operculum and the capitellate vegetative 
cell. The dimensions above, from the Iowan material, also 
include those of the Austrian specimens. 
89. Oe. mitratum Hirn. 
(Pl. XXXVI, figs. 334 and 335.) 
1895, p: 22, Pl. 1, fig. 7; 1900; p. 302, Pl. XXIV, fie. 132. 
Dioecious, macrandrous; oogonium 1-4, globose or subglobose, 
operculate, division supramedian or superior, narrow but distinct; 
oospore globose (rarely subglobose), filling oogonium, spore wall smooth; 
antheridium 1—5, subepigynous, sperms 2, division horizontal; vegetative 
cell often broadly capitellate; vegetative cell 5-10 18-80u; oogonium 
18—24 X 20—-28u; oospore 17—23 X 17—22u; antheridium 6-9 X6-8uy. 
United States: Illinois; Austria, Finland, Sweden. 
Hirn (1900) records this species as doubtfully monoecious, 
but material from Illinois (Transeau) shows it to be definitely 
dioecious, macrandrous. The emended description was sup- 
plied from the Illinois material. Cf. Oe. petri below. 
90. Oc. petri Wittrock. 
(Pl. XXXVI, fig. 332.) 
1874, p. 6; Hirn 1900, p. 154, Pl. XXIV, fig. 127. 
Monoecious; oogonium 1 (rarely 2), pyriform or pyriform-globose, 
operculate, division a little above median; oospore subdepressed or 
