lia
campanella_. It occurs throughout the summer and autumn on dead or
rotten logs, stumps, branches, etc., in woods. It is often clustered,
large numbers covering a considerable surface of the decaying log. It is
1--3 cm. high, the cap 8--20 mm. broad, and the stem very slender.

The =pileus= is convex, umbilicate, faintly striate, dull reddish
yellow, in damp weather with a watery appearance. The =gills= are
narrow, yellow, connected by veins, strongly curved because of the form
of the pileus, and then being decurrent on the stem. The =stem= is
slender, often ascending, brownish hairy toward the base, and paler
above.

[Illustration: FIGURE 104.--Omphalia epichysium. Entire plant smoky or
dull gray in color (natural size). Copyright.]

=Omphalia epichysium= Pers.--This plant occurs during the autumn in
woods, growing usually on much decayed wood, or sometimes apparently on
the ground. The smoky, or dull gray color of the entire plant, the
depressed or funnel-shaped pileus, and short, slender stem serve to
distinguish it. The cap is 2--4 cm. broad, the plant is 3--5 cm. high,
and the stem 2--4 mm. in thickness.

The =pileus= is convex, becoming expanded, umbilicate or depressed at
the center or nearly funnel-shaped, smooth, smoky or gray with a
saturated watery appearance, light gray or nearly white when dry. The
=gills= are narrow, crowded, or a little decurrent. The slender =stem=
is smooth, hollow, equal. Figure 104 is from plants (No. 3373, C. U.
herbarium) collected in woods near Ithaca, N. Y., in the autumn of 1899.

PLEUROTUS Fr.

[Illustration: FIGURE 105.--Pleurotus ulmarius. Cap white, or with
shades of yellow or brown near the center (natural size). Copyright.]

The genus _Pleurotus_ is usually recognized without difficulty among the
fleshy, white-spored agarics, because of the eccentric (not quite in the
center of the pileus) or lateral stem, or by the pileus being attached
at one side in a more or less shelving position, or in some species
where the upper side of the pileus lies directly against the wood on
which the plant is growing, and is then said to be _resupinate_. The
gills are either decurrent (extending downward) on the stem, or in some
species they are rounded or notched at the junction with the stem. There
is no annulus, though sometimes a veil, and the genus resembles both
_Tricholoma_ and _Clitocybe_, except for the position of the stem on the
pileus. In _Tricholoma_ and _Clitocybe_