OEDOGONIUM 77 
Iwanoff and Silfvenius (/oc. cit.) both found material of 
this species which proved it to be monoecious and not dioecious 
(Hirn 1900, 1906). It is characterized by the relatively short 
oospore within a much longer oogonium. The diameter of the 
oospore is such that the lower part of the oogonium is really 
inflated. It bears some resemblance to Oe. paludosum (No. 53) 
and Oe. boscit (No. 55). From both it is distinguished by its 
smooth oospores. It is unlike Oe. bosci in its monoecious habit. 
28. Oe. sodiroanum Lagerheim. 
(Pl. XVI, figs. 153 and 154.) 
1890, p. 81; Hirn 1900, p. 118. 
Monoecious; oogonium 1, ellipsoid-obovoid, pore superior; oospore 
ellipsoid, not filling oogonium at upper end, spore wall smooth; 
antheridium subhypogynous or subepigynous or scattered, 1-9; sperms 2, 
division vertical; vegetative cell 20-2444-84y; oogonium 40-45 
70-90u; oospore 38-42 x 56-64; antheridium 20-22 6-8u. 
United States: Michigan; Ecuador. 
This species originally described incompletely from Ecuador 
by Lagerheim was collected nearly forty years later in Michigan 
by Miss Alma B. Ackley. The above description is based on 
the Michigan material. There can be no question of the validity 
of the species. It resembles in general appearance Oe. oviforme 
(No. 30), Oe. upsaliense (No. 29), and Oe. richtertianum (No. 26). 
It is readily distinguished from these (Cf. No. 29) in dimensions 
and habit. The antheridia occur in series and when present 
at the end of the filament give the plant a curved appearance, 
not unlike that of the androsporangial filaments of Oe. spectabile 
(No. 186). 
29. Oe. upsaliense Wittrock. 
(Pl. XVI, fig. 157.) 
1870, p. 125; 1872a, p. 22; 1874, p. 14, Pl. I, fig. 4; Oe. tumidulum (Roth) in 
Areschoug Alg. Exs. No. 236, 1864; Hirn 1900, p. 115, Pl. XII, fig. 60; Wittr. and 
Nordst. Alg. Exsicc. No. 18; P. B. A. No. 1576: 
Monoecious; oogonium 1, obovoid or suboblong-ellipsoid, pore 
superior; oospore same form as oogonium (which it fills), spore wall 
smooth; antheridium 1-3, subhypogynous; antheridium, oogonium, 
and vegetative cell alternating; sperms 2, division vertical; vegetative 
cell varying much in same filament; suffultory cell up to 27u in diameter; 
basal cell elongate; terminal cell obtuse; vegetative cell 13-20 * 55-160y; 
oogonium 45-50 x 66—-100u; oospore 42-47 x 60-75u; antheridium 15-18 
x 7-10n. 
United States: Michigan, New Hampshire, Ohio, Illinois; 
Greenland; France, Germany, Sweden, Latvia. 
