138 
Y. B. Wittrock. 
leato; nannandribus bicellularibus ; crassitudine cellularum 
vegetativarum 8—12 altitudine 6—14plo majore; cras¬ 
situdine oogoniorum c:a 35 diametro oosporarum (sine 
aculeis) c:a 25 /a. 
Hab. in America boreali in stagnis montium Alleg¬ 
hany; sec. Prof. H. C. Wood. 
The same may be said of this diagnose as of that of 
Oe. multisporum Wood, and Oe. Huntii Wood. — The 
species is most nearly related to Oe. Aster Wittr., but 
differs from it in the following respects: the pore of fe¬ 
cundation is placed in the upper part of the oogonium; 
the exosporium has thicker spines; and the vegetative 
cells, are somewhat thicker and longer. — The seat and 
more special nature of the dwarf male-plants is not de¬ 
scribed by Wood. 
C. Species dioicæ macrandriæ. 
12. Oe. mexicanum nov. spec. 
Oe. dioicum, macrandrium, oogoniis singulis, paullum 
tumidis, cylindrico-oboviformibus, poro foecundationis in 
parte superiore oogonii sito ; oosporis oogonia fere explen¬ 
tibus, exosporio lævi (?) ; cellulis suffultoriis eadem forma 
ac cellulis vegetativis ceteris; filis masculis eadem fere 
crassitudine ac filis femineis; spermogoniis 4—8cellulari- 
bus, spermatozoidiis binis, divisione verticali ortis; 
crassit. cell, veget. 34—40 /u, altit. 1 3 / 4 —3 V 2 pio majore; 
,, oogon. 54—62,, „ 77—110 
„ oospor. 52—60 „ „ 63—80 „ 
„ cell, spermog. 33—35 ,, „ 7—15 „. 
Hab. in Mexico ad Orizaba, ubi cel. F. Müller legit 
18 2 53; see. specimina in museo botanico universitatis Ar- 
gentoratensis asservata. 
This species seems to have a near relative in Oe. gi- 
ganteum Kütz. But it is not possible to decide upon this 
with perfect certainty, the male-plants of Oe. giganteum 
not being known. But the resemblances between the fe¬ 
male plants of the two species are very great. The dif- 
