ATKINSON: THE GENUS ENDOGONE 3 
Formation of the ‘resting spore’’ and simple zygocarp.—The “‘resting 
spore”’ in Endogone lactiflua is not formed in the immediate zygote 
resulting from the fusion of the two gametangia nor in the oogone, 
but in an outgrowth from the latter. During and immediately after 
fusion of the two gametangia their walls become thickened and firm, 
so that they can not yield to the pressure from the young growing 
zygote. Asa result there arises a sack-like outgrowth from the end 
of the oogone into which the cytoplasm from the two gametangia flows 
accompanied by the two gamete nuclei, the antheridial nucleus fol- 
lowing the oogonial nucleus. The sac-like outgrowth enlarges into 
an oval or broadly elliptical resting zygote. A thick, stratified, 
hyaline, cartilaginous wall is formed next to the primary zygote 
membrane, which entirely encloses the cytoplasm and other contents, 
thus separating them from the empty oogone. The two gamete 
nuclei lie side by side in the center of the zygote but do not fuse until 
after the resting period, except in a small variety from Germany in 
which the gamete nuclei fuse at once according to Bucholtz. During 
the growth and ripening of the zygote it becomes enveloped by slender 
branches which coil in a more or less spiral manner around it forming 
a thick cover of small cells, 2-3 cell layers deep, the walls of these 
cells become greatly thickened and fuse next the zygote, grading out 
to the thin walls of the surface. Each resting spore, or zygote, with 
its individual cellular envelope forms a simple fruit or simple zygocarp 
(zygosporocarp, as Bucholtz terms it). The fruit body of Endogone 
lactiflua is filled with these simple zygocarps intermingled with the 
mycelium, and is therefore a compound zygocarp. Germination of 
the ‘“‘resting spores’? has not been observed. Endogone lactiflua is 
the only species of the genus in which such simple zygocarps are known, 
1. €.,a fruit body with a single zygote enclosed in its individual envelope. 
ENDOGONE SPHAGNOPHILA 
In July, 1916, a day or two before the close of a fungus foray 
organized by Mr. F. C. Stewart at his camp on Seventh Lake, in the 
Adirondacks, Mr. W. H. Sawyer, Jr., a member of the party, brought 
in some sphagnum on which were rounded, pulvinate, orange-yellow 
bodies resembling the plasmodiocarps of certain slime molds. A pre- 
liminary examination of the internal structure revealed the fact that 
it was not a slime mold, but apparently a phycomycete with large 
resting spores having a thick, hyaline, stratified, cartilaginous wall, 
and orange-yellow content. A pair of stalks, or suspensors, attached 
to one end of the resting spores in different stages of development, 
indicated that they had their origin in an interesting type of conjuga- 
tion. In the afternoon of the same day (July 31, 1916) Mr. Sawyer 
