THE GREEN ALGAE OF NORTH AMERICA 69 



cell usually swollen ; basal cell usually elongate, terminal 



obtuse ; dwarf males nearly erect, on suffultory cell ; anthe- 

 ridium exterior, i-2-celled. 



veg. cell, 20-33 M diam., 3-7 diam. long, 



suff. cell, 25-37 /i " 3-5 " " 



oog., 66-82 M " 73-88 M long, 



nan. stipe, 10-14 u " 37-48 M " 



anth. cell, 9-12 /i " 7 n " 



Charleston, 111., Transeau. Brazil. 



In many of its characters like Oe. acrosporum De Bary, but 

 larger throughout, with oogonia of more variable shape, usually 

 thicker in proportion to the length. 



87. OE. DEPRESSUM Pringsheim ex Him, 1900, p. 249, PI. 

 XLJI, fig. 261. Dioecious, nannandrous, gynandrosporous ; 

 oogonium single, depressed-globose, pore median ; oospore 

 depressed-globose, not filling the oogonium ; androsporangium 

 2-celled ; dwarf males oblong-oboviform, on the oogonium ; 

 antheridium interior. 



veg. cell, 8-9 /j. diam., 3-6 diam. long, 



oog., 28 n " 26 n long, 



oos., 23 /A " 17.5 M " 



nan. cell, 4-5 M " 14-16 M " 



Greenland, P. Richter. Germany. 



88. OE. CRASSUM Wittrock ex Him, 1900, p. 139, PI. 

 XVIII, fig. 99. Dioecious, macrandrous ; oogonium single, 

 rarely 2, oboviform-ellipsoid, pore superior ; oospore ellipsoid 

 or globose-ellipsoid, not filling the oogonium, membrane 

 smooth ; male plants somewhat more slender than female ; 

 antheridium up to 2o-celled ; spermatozoids binate, division 

 vertical. 



veg. cell, 40-49 /* diam., 2-4 diam. long, 



oog., 68-75 fj. " 93-125 M long, 



oos., 63-69 /* " . 75-i 10 /t " 



Hanover, Ohio; New Buffalo, Mich., Transeau. Europe. 



89. OE. REINSCHII Roy ex Hirn, 1900, p. 319, PI. L, fig. 

 326. Cells generally hexagonal in vertical section (widest at 

 the middle) occasionally subellipsoid or subcylindrical ; basal 

 cell not elongate, subhemispherical ; terminal cell obtuse. 



veg. cell, 6-9 M ( -u) diam., 1.25-2.5 diam. long, 



basal cell, 8-9 /* 5-6 M long. 



Fla., Borge. Europe, South America. 



