108 THE OEDOGONIACEAE 
95b. Var. nordstedtii Wittrock, 
(Pl. XXXV, figs. 327-330. ) 
In Wittr. and Nordst. Alg. Exs. No. 8, 1877; Oe. ciliare De Notaris 1868, p. 120; 
Oe. franklinianum Wittr. in Tilden Amer. Alg. No. 2, 1894; Oe. nordstedtii Wittr. 
1872, p. 6, Pl. 1, figs. 7 and 8; Oe. pringsheimii var. varians Nordst. 1888, p. 11, Pl. 1, 
fig. 9; Oe. pachydermatosporum Nordst. in Lewin 1888, p. 18, Pl. 3, fig. 56; Hirn 
1900, p. 171, Pl. XXVII, figs. 156-158; Oe. pringsheimit Cram.; Wittr. var. nord- 
stedtur Wittr. f. euganeorum (Wittr.) Hirn 1900, p. 172, Pl. X XVII, fig. 159; Oe. 
euganeorum Wittr. 1874, p. 39; Tiffany 1926, p. 98, Pl. V, fig. 47. 
Smaller than the type, oogonium 1-2; oospore not filling oogonium; 
female vegetative cell 10-1620-76yu, male 9-15X18-68y; oogonium 
28-39 X 36—45u; oospore 26-34 x 27-34u; antheridium 9-12 8-9u. 
United States: Minnesota, California, Iowa, Illinois, Ohio, 
Michigan; Austria, England, Finland, Latvia, Germany, Italy, 
Switzerland, Spain; India; Patagonia; Greenland; Samoa. 
Oe. pringsheimit is characterized by its subovoid-globose 
oogonia and superior position of the operculum, among the 
dioecious species. Its oogonia are smaller than either Oe. 
towense (No. 93) or Oe. welwitschit (No. 92). The variety 
abbreviatum has shorter vegetative cells and var. nordstedti 
is more slender than the type. 
96. Oe. nodulosum Wittrock. 
(Pl. XXXIX, figs. 374 and 375.) 
1872a, p. 22, Pl. 1, figs. 8-10; 1874, p. 13, Pl. 1, figs. 2 and 3; Borge 1899, p. 6, 
Pl. 1, fig. 3; Hirn 1900, p. 187, Pl. X XIX, fig. 184. 
Monoecious; oogonium 1-2, obovoid-globose or more rarely obovoid- 
ellipsoid, operculate, division superior; oospore globose or subglobose or 
more rarely globose-ellipsoid, nearly filling oogonium, spore wall smooth, 
often thick; antheridium 1-3, subepigynous or hypogynous; sperms 2, ~ 
division horizontal; basal cell elongate, not constricted; terminal cell 
obtuse or apiculate; vegetative cell, with two undulate constrictions, 
20-29 < 30-140u; oogonium 48-57 X56-73u; oospore 46-53 49-56u; 
antheridium 18-25 7-9u. 
Australia; China; Patagonia; England, Sweden. 
96a. Var. commune Hirn. 
(Pl. XXXIX, fig. 376.) 
1900, p. 187, Pl. XXX, fig. 185; Oe. nodulosum Wittr. in P. B. A. No. 74, 1895, 
and im Hirn 1895, p. 138; Collins 1909, p. 248. 
Oogonium subobovoid-ellipsoid to ellipsoid or more rarely globose- 
ellipsoid; vegetative cell 22-2935-140u; oogonium 64-74 70-90y; 
oospore 56-70 X67-80u; antheridium 18-26 X7-10uy. 
United States: Massachusetts; Finland, Sweden. 
The nodulose character of the vegetative cells is very 
distinctive. Oc. sphaerandrium (No. 105) sometimes has nodu- 
lose cells, but it is much smaller. Var. commune has larger 
