256 TUFTS COLLEGE STUDIES, VOL. II, No. 3 



veg. cell, 15-23 M diam., 3-6 diam. long. 



suf. cell, 31-38 /u " i^-2>^ " " 



oog., 40-50 M " 55-9 /"long. 



oos., 35-46 fj. " 48-60 n " 



andr. cell, 16-19 M " 15-23 M " 



nan. stipe, 12-15 M " 35'47 M " 



anth. cell, 7-10 M " 11-15 ^ " 



Mass., Pa., Cal. Europe, Australia, So. America. 



A common species, distinguished from Oe. crassinsculum by 

 the much swollen cell below the oogonium ; the cells are rela- 

 tively slender just above the oogonium, and increase rapidly 

 and uniformly to and including the oogonium ; above this the 

 cell is slender again ; from the two following species, Oe. Wolle- 

 anum and Oe. concatenation, it is distinguished by the oospore 

 being smooth, not striate. 



57. OE. WOLLEANUM Wittrock, i878a, p. 137 ; Wolle, 1887, 

 p. 82, PI. L,XXX, figs. 4 and 5; Him, 1900, p. 220, PI. 

 XXXVII, fig. 226; Wittr. and Nordst., Alg. Exsicc., No. 107. 

 Dioecious, nannandrous, gynandrosporous or idioandrosporous ; 

 oogonia single or 2, more rarely 3-4, suboboviform or quadran- 

 gular-ellipsoid, pore superior, membrane with raised longitud- 

 inal lines on the inner surface ; oospore same form as the oogo- 

 nium, quite filling it, membrane double ; external membrane 

 with 25-35 longitudinal raised lines, rarely anastomosing ; inner 

 membrane smooth ; suffultory cell swollen ; androsporangia 1-3- 

 celled, often subepfgynous, or scattered in the upper part of the 

 filament ; basal cell elongate ; terminal cell, which is some- 

 times an oogonium, short acute or acuminate ; dwarf males on 

 suffultory cell, stipe slightly curved ; antheridium exterior, 1-3- 

 celled. 



veg. cell, 21-30 fj. diam., 3-8 diam. long. 



suf. cell, 45-56 M " 1^-2 " 



oog., 58-68 fj. " 69-89 M long. 



oos., 56-66 M " 65-83/11 " 



andr. cell, 21-30/1* " 18-25/11 " 



nan. stipe, 15-24 /" " 54-6o /* " 



anth. cell, 9-14 /u " 7-11 M " 



Greenland, Mass., Conn., N. J., Pa., Minn., Fla. 



Europe, Asia, So. America. 



A cosmopolitan species, and generally quite uniform in its 

 characters ; it is distinguished from Oe. Botisianum and Oe. con- 

 catenatum by the lines on the oogonium and the oospore, the 

 two fitting closely, the elevations on one into the furrows in 



