150 THE OfbDOGONDACE AE 
181. Oe. hoersholmiense Hallas. 
(Pl. LVII, fig. 559.) 
1905, p. 400, fig. 5; Hirn 1906, p. 15, Pl. IV, fig. 21. 
Dioecious, nannandrous, gynandrosporous; oogonium 1 (rarely 2), 
ellipsoid, operculate, division superior; oospore ellipsoid or globose, 
not filling oogonium, spore wall smooth; androsporangium 1-5, often 
hypogynous or scattered; basal cell elongate; terminal cell obtuse; 
dwarf male curved, on oogonium, antheridium exterior, 1-2; vegetative 
cell 7-12 44-160u; oogonium 30-36 X 56-68; oospore 26-32 X 32-45y; 
androsporangium 7—-12X16-2lu; dwarf male stipe 9-12*30-35y; 
antheridium 7—8 X 10—l1yu; basal cell 3-14 x 16-50p. 
Denmark. 
This species is perhaps near Oe. ciliatum (No. 185) from 
which it differs in its smaller size, longer vegetative cell, and 
obtuse terminal cell. The figure of Hallas would seem to 
indicate an operculum in a supreme position, although the 
description records ‘‘superior.’’ I have included it in both 
positions in the key. 
182. Oe. laetevirens Wittrock. 
(Pl. LVI, fig. 558.) 
In Zeller 1876, p. 427; Hirn 1900, p. 239, Pl. XL, fig. 247. 
Dioecious, nannandrous; oogonium | (rarely 2), subobovoid-globose, 
operculate, division superior; oospore globose or subdepressed-globose, 
filling oogonium or enlarging it, spore wall smooth; dwarf male on 
oogonium, stipe a little curved, antheridium exterior, 1—?; vegetative 
cell 12-13 X 18-32u; oogonium 30-34 X 32-36; oospore 28-32 XK 27-29; 
dwarf male stipe 7-8 x 20-21y; antheridium 6X 5-7y. 
Brazil. 
Cf. Oe. macrandrium (No. 184). 
183. Oe. pluviale Nordstedt. 
(Pl. XL, figs. 392 and 393.) 
In Rabenh. Alg. Eur. No. 2257, 1871; Wittr. 1872, p. 7; Oe. intermedium Kuetz. 
in Rabenh. Alg. Sachs. No. 828, 1859; Oe. montagnei Fior.-Mazz. var. submarinum 
Wittr. im Wictr. and Nordst. Alg. Exs. No. 905, 1889; Oe. fonticola Al. Br. in Wolle 
1887, p. 93, Pl. 75, figs. 4-6; (?) Vesiculifera dissiliens Hass. 1845, p. 202, Pl. 50, 
fig. 7; Oe. diplandrium Juranyi 1873, p. 27, Pl. 1-3; (?) Oe. fonticola Al. Br. var. 
flavescens Hansg. 1891, p. 305; Oe. montagnei Fior.-Mazz. var. saxicolum Wittr. 1876, 
p. 50, Pl. 18, figs. 29-31; Hirn 1900, p. 280, Pl. XLVIII, fig. 311; P. B. A. No. 1190. 
Dioecious, nannandrous, idioandrosporous; oogonium 1 (very rarely 
2-3), obovoid-globose or subglobose, operculate, division superior; 
oospore subglobose or subellipsoid-globose, almost filling oogonium, 
spore wall smooth; vegetative cell varying much in the same plant; 
basal cell elongate; terminal cell obtuse; androsporangium to 10-seriate; 
dwarf male broadly obovoid, unicellular, on oogonium; vegetative 
cell 22-29 20-55u; androsporangial vegetative cell 18-27X18-27y; 
oogonium 34-4534-50u; oospore 32-4031-43yu; androsporangium 
17-25 X 6-13; dwarf male 10X 14—15p. 
