ATKINSON: THE GENUS ENDOGONE 5 
No cross walls have been observed, except in the progametes after copu- 
lation. The nuclei are minute, very numerous and lie in the peri- 
pheral granular cytoplasm. There is a nuclear membrane and a 
large nucleolus (? karyosome). The fruit bodies are quite firmly 
attached to the living sphagnunt leaves, but the mycelium does not 
appear to be parasitic, although short haustoria have been seen pene- 
trating the cell. The hold-fast is a rather compact lattice-like layer 
of mycelium forming a kind of “‘sole,’’ very closely applied to the 
surface of the leaves, from which here and there the short haustoria 
arise. The fungus is probably nourished by organic and mineral 
solutions carried by the sphagnum from the water of the humus 
substrate in the capillary stream so well provided for in the peat 
mosses. 
Conjugation of the progametes.—While there is a great resemblance 
in the process of conjugation and in the formation of the resting zygote 
of Endogone sphagnophila to the situation in E. lactiflua, the details 
of the process are quite different in the two species. The progamete 
branches lie nearly or quite parallel. In a few cases where they have 
been observed just prior to conjugation they do not appear to be 
differentiated from ordinary stout vegetative branches, except that 
the cytoplasm is more dense and abundant. They do not appear to 
be enlarged or clavate. In fact many of the vegetative branches are 
clavate and sometimes they are in pairs lying closely side by side, 
but in no case have I been able to determine with certainty that such 
branches are progametes. The progametes also appear to be un- 
differentiated before conjugation. They conjugate by lateral contact 
of their walls at the tip. Immediately after contact the progametes 
begin to swell into a clavate or fusoid form, and the wall at the point 
of contact is resorbed for some distance, thus forming a broad com- 
municating area where the cytoplasm of the two merges. During the 
enlargement one of the gametes frequently becomes larger than the 
other. The cytoplasm is very dense and fills the distal portion of the 
progametes, while in the proximal direction the cytoplasm is less 
abundant and lies chiefly in a peripheral zone next the wall. <A cross 
wall is now laid down in each progamete a short distance behind the 
broad communicating pore, separating the gametangia from the stalks 
or suspensors. 
Formation of the resting spore or resting zygote-—At the time of 
conjugation and resorption of the contact wall the conjugating game- 
tangia resembles the same stage of conjugation in Eremascus fertilis. 
The zygote is not formed by the enlargement of the copulating game- 
tangia as in the majority of the Mucorales, but the young zygote 
begins to grow at once in an apical direction. Sometimes the origin 
