68 TUFTS COLLEGE STUDIES, VOL. IV, No. 7 



84. OB. PRATICOLUM Transeau, 1914, p. 298, PI. XXIX. 

 figs. 1-5. Dioecious, (?) nannandrous, id ioandros porous ; oogo- 

 niutn single, more rarely 2-7, ellipsoid to globose-ellipsoid, 

 often terminal, sometimes scattered, wall sometimes rather 

 thick, operculate, division superior, near summit, lid very 

 small, deciduous; oospore ellipsoid to globose-ellipsoid, quite 

 filling the oogonium ; membrane smooth ; androsporangial fila- 

 ments a little smaller than female filaments ; androsporangium 

 i-zo-celled; vegetative cells slightly capitellate, basal cell usu- 

 ally elongate ; terminal cell apiculate or extended into a long 

 hyaline seta. 



Charleston, 111., Transeau. 



Related to Of. obtrnncatum Wittr., but somewhat larger, 

 idioandrosporous, and with different form of terminal cell. 



85. OE. PKOPiNyuuM Wittrock ex Him, 1900, p. 236, PI. 

 XL, fig. 243. Dioecious, nannandrous ; oogonium single or 2, 

 oboviform-globose, operculate, division superior ; oospore glo- 

 bose, nearly filling the oogonium, membrane smooth; dwarf 

 males near or on oogonium, stipe curved ; antheridium exterior, 

 i-2-celled. 



veg. cell, 10-13 M diam., 3-5 diam. long. 



oog., 20-36 M " 35-45 M long. 



00., 24-31 M " 24-31 M " 



nan. ttipe, II-IJM " 20-23 M " 



antb. cell, 7-8 M " 6-8 M " 



Charleston, III., Transeau. Europe. 



Near Oe. macrandrium , Wittr., but the latter has larger 

 dimensions, and the oogonia are more generally seriate. 



86. OB. TBNTORIALB Nordstedt & Him in Him, 1900, p. 

 248, PI. XLII, fig. 260. Dioecious, nannandrous; oogonium 

 single, terminal, short-ellipsoid or oboviform-glolx>se, opercu- 

 late. division superior, lid very small, deciduous ; inner surface 

 of membrane with longitudinal ribs, sometimes anastomosing ; 

 oospore completely filling oogonium, its membrane uniting with 

 that of the oogonium ; epispore longitudinally ribbed, with fine 

 striations between the ribs, about 40-45 ribs at the middle of the 

 oospore, ribs minutely crenulate ; endospore smooth ; suffultory 



