20 CIRCULAR 143, U. S. DEPARTMENT OF AGRICULTURE 
CLITOCYBE DEALBATA. (SUSPECTED ) 
In this species the cap is convex, then plane, finally revolute and undulate, 
dry, even, smooth, somewhat shining; the flesh is thin, dry, white; the gills 
are adnate, crowded, scarcely decurrent, white; the stem is equal, erect, or 
ascending, stuffed, wholly fibrous, apex subpruinose. ~ 
While this species has been considered edible, it may easily be mistaken for 
Clitocybe sudorifica, a very dangerous fungus known as the “ sweat-producing 
Clitocybe. 
CLITOCYBE ILLUDENS. JACK-O’-LANTERN. (POISONOUS) 
(Fig. 19) 
In Clitocybe illudens the cap is fleshy, convex or expanded, then depressed, 
sometimes with a small umbo, saffron yellow, in age becoming sordid or 
brownish; the gills are broad, distant, and unequally decurrent; the stem is 
FIGURE 19.—Clitocybe illudens. (Poisonous.) (From M. A. Williams) 
solid, firm, smooth, and tapering toward the base, ascending, curved, rarely 
erect, color Same as Gap. 
The cap is 4 to 6 inches broad; the stem is 5 to 8 inches long. 
This is a very striking fungus on account of both its color and the large 
clumps it forms about stumps or decaying trees. It is often irregular in form, 
from the crowded habit of growth. On account of the phosphorescence which 
renders it conspicuous at night, it is commonly known as the jack-o’-lantern. 
While not considered a dangerous poisonous species, it produces illness and is 
to be carefully avoided. It may be found from August to October. 
OMPHALIA 
In the genus Omphalia the cap is generally thin, at first umbilicate, 
but later funnel shaped, with the margin either incurved or straight. 
The stem is cartilaginous, its flesh being continuous with that of the 
pileus but differing in character. Species of Omphaha are common 
on rotten wood on hilly slopes and are especially abundant in damp 
weather. Some species are extremely small. 
This genus is closely related to Mycena and Collybia, but it is dis- 
tinguished from them because of its decurrent gills. 
