THE GREEN ALGAE OF NORTH AMERICA 247 



A widely distributed species, but the occurrence with us of 

 the typical form is recorded only by Wolle, who does not men- 

 tion var. Nordstedtiii which certainly does occur here ; possibly 

 his plants belong rather to the variety. 



Var. NORDSTEDTII Wittrock in Wittr. and Nordst., Alg. 

 Exsicc., Nos. 8 and 205; Him, 1900, p. 171, PI. XXVII, fig. 

 156. Smaller, oogonia single, rarely 2, oboviform-globose, 

 oospore not quite filling the oogouiuui. 



veg. cell, female, 10-16 /u diam., 2-4^ diatn. long. 



veg. cell, male, 9-15 M " 2-4% " " 



oog., 28-39 /x " 3 6 -45 Mcmg. 



oos., 26-34 n " 27-34 M " 



anth. cell, 9-12 /u " ,8-9 /u " 



Greenland, Minnesota, Cal. Europe, Asia. 



MACRANDRIA, OPERCULATA, ELLIPSOSPORA. 



39. OE. AHLSTRANDII Wittrock in Wittr. and Nordst., Alg. 

 Exsicc., No. 401 ; Him, 1900, p. 183, PI. XXIX, fig. 179. 

 Monoecious; oogonia ellipsoid, single, operculate, division su- 

 perior ; oospore ellipsoid, filling the oogonium, membrane 

 smooth ; antheridium i-2-celled, hypogynous ; spermatozoids 

 binate, division horizontal ; terminal cell obtuse. 



veg. cell, 10-18 M diatn., 3-10 diam. long, 



oog., 34-42 M " 57- 6 9 /* long, 



oos., 34-41 M " 53-62 n " 



anth. cell, 13-17 M " 9' 12 M " 



N. Y. Sweden. 



40. OE. GRACIIXIMUM Wittrock and Lund in Wittrock, 

 1874, p. 15 ; Wolle, 1887, p. 74, PI. LXXV, fig. 2 ; Hirn, 1900, 

 p. 184, PI. XXIX, fig. 1 80. Monoecious; oogonia single, 

 oblong, operculate, division superior ; oospore oblong-ellipsoid, 

 not filling the oogonium, membrane smooth ; antheridia subepi- 

 gynous, hypogynous or subhypogynous, unicellular ; spermato- 

 zoids binate, division horizontal. 



veg. cell, 3^-7 Mdiam., 4/^-6 diam. long. 



' oog., 14-19 M " 34-40 M long, 



oos., 13-17 M " 24-32 M 



anth. cell, 3'5 * " 47 M 



p a Europe. 



41. OE. NODULOSUM Wittrock, 1872, p. 22, PI. I, figs. 8-10; 

 Him, 1900, p. 187, PI. XXIX, fig. 184. Monoecious; oogonia 

 single or 2, oboviform-globose, more rarely oboviform-ellipsoid, 

 operculate, division superior; oospore globose or subglobose, 

 more rarely globose-ellipsoid, almost filling the oogonium, mem- 



