ical or spheroidal, purplish-gray or brown, smooth,
shining; the peridium thick, simple but in microscopic section showing
two or three successive layers; capillitium of abundantly branching,
irregular, transparent tubules, marked by numberless warts and
transverse rings or wrinkles, spores in mass yellowish gray, by
transmitted light, colorless, smooth or only faintly reticulate or
roughened, 5-6 mu.

This, one of the largest and most striking of the slime-moulds, is by
students generally mistaken for a puff-ball. It occurs on stumps and
rotten logs of various sorts in the Mississippi valley, more often
affecting stumps of _Acer saccharinum_ L. The fructification, when
solitary, about the size of a walnut, though sometimes larger; when
clustered, the individuals are smaller. The form depends largely upon
the place in which the fruit is formed. The plasmodic mass is so large
that its form is determined by gravity. Thus on the lower surface of a
log raised a little distance from the earth the aethalium is often
pyriform. This fact did not escape Micheli. See _Nov. Plant. Gen._, Tab.
95. The plasmodium is pale pink, soon becomes buff when exposed in
fruiting, finally pallid or somewhat livid, and is outwardly changed
into the stout, tough peridium. This consists of an intricate network of
irregular gelatinous tubules enclosing within the meshes protoplasmic
masses of pretty uniform size, 60-100 mu. Outwardly the protoplasmic
vesicles predominate; inwardly the gelatinous tubules, which are, in
some instances at least, continued toward the centre of fructification
to form the capillitium. The protoplasmic masses referred to respond to
ordinary stains, are often broken into numberless small cells
corresponding in size and appearance to ordinary spores.

Not common. New England, Ohio, Iowa. Perhaps more abundant in the
Mississippi valley; Canada.

3. LYCOGALA EXIGUUM _Morg._

1893. _Lycogala exiguum_ Morg., _Jour. Cin. Soc._, p. 8.

Aethalia small, 2-5 mm. in diameter, gregarious, globose, dark brown or
black, sessile, minutely scaly, irregularly dehiscent; the peridium
thin, the vesicles comparatively few, in irregular patches which are
more or less confluent; capillitium as in preceding species, the tubules
slender and branching; spore-mass pale, ochraceous, spores by
transmitted light colorless, almost smooth, 5-6 mu.

Found in the same situations as No. 1, and at the same season.
Recognizable by its _gregari