Oedogonieæ Americanae, hucusque coguitæ. 
139 
ferences in Oe. mexicanum are almost only that the sup¬ 
porting cells have the same shape as the other vegetative 
cells and that the exosporium is smooth. I have not had 
an opportunity to see perfectly ripe spores of Oe. mexi¬ 
canum , and it is not quite; impossible that the exosporium 
in those may be in some way sculptured. 
13. Oe. punctato- striatum De Bar. — Wittr. Prodr. 
Monog. Oedog. pag. 34. 
Hab. in Groenlandia ad Claushavn, ubi legit Prof. 
Th. M. Fries. 
14. Oe. crenulato-costatum nov. spec. 
Oe. dioicum, macrandrium; oogoniis singulis vel ra¬ 
rius binis, oboviformibus, poro foecundationis in parte su¬ 
periore oogonii sito; oosporis oogonia fere explentibus, 
endosporio longitudinaliter crenulato-costato ; cellulis suf- 
fultoriis eadem forma ac cellulis vegetativis ceteris; filis 
masculis paullo gracilioribus quam femineis; spermogoniis 
in parte superiore fili cum cellulis vegetativis alternis, 2—6- 
cellularibus; spermatozoidiis binis, divisione horizontali 
ortis; cellula terminali (quæ interdum est oogonium) obtusa; 
crass, cell. veg. plant, femin. 12—18 /u, alt. 2 3 / 2 -4plo majore; 
,, ,, ,, ,, mascul. 9 13 ,, ,, 3 / 2 d / 2 plo ,, 
„ oogon. 32—33,, „ 48—58 q; 
„ oospor. 29—30 „ „ 42—47 „ 
„ cell, spermog. 9-12 „ „ 9—14 „. 
Hab. in Pennsylvania ad Bethlehem, ubi rev. F. Wolle 
legit. D:r L. Rabenhorst hanc speciem mihi benevole com¬ 
municavit. 
The nearest relative of this species is Oe. Boscii (Le 
Cl.) Wittr. Oe. crenulato-costatum differs through the pe¬ 
culiar sculpture of the endosporium, through having nar¬ 
rower and shorter vegetative cells, (especially the male 
specimens), an obtuse top-cell and the oospore almost filling 
the oogonium. 
15. Oe. Boscii (Le Cl.) Wittr. Prodr. Monog. Oedog. 
pag. 34. 
