16 NEW YORK STATE MUSEUM 
ulum; teeth scattered, minute, .1-.25 mm long, .05-.1 mm broad, 
obtuse. often forked, colored like the subiculum but paler or white 
at the subciliate tips. Growing chiefly on the hymenial surface 
of Stereum frustulosum but often spreading over the 
substratum of decayed wood. Mt McGregor, Saratoga co. July. 
The growth is most vigorous on the surface of the Stereum, 
where the subiculum becomes thickest and the teeth most numer- 
ous. On the woody substratum the growth is poor, the subiculum is 
thin and often the mycelium spreads naked over the surface of the 
wood. This has suggested the specific name. The thinning out of 
the subiculum indicates that the fungus finds its proper nourish- 
ment in the tissues of the Stereum and it is doubtful if it will be 
found dissociated from that plant. It appears to be related to 
H. sulphurellum Pk. but differs from it in color, in the 
indeterminate margin and in the ciliate teeth. 
Inocybe castanea n. sp. 
PLATE 0, FIG. 1-8 
Pileus conic or convex, umbonate, rimose fibrillose, the margin 
incurved, dark chestnut brown; lamellae thin, narrow, close, 
adnate, whitish or pallid when young, ferruginous brown when 
mature; stem equal, hollow, glabrous, slightly pruinose or mealy 
at the top; paler than the pileus; often whitened at the base by 
mycelioid tomentum; spores angular, nearly or quite as broad 
as long, .00025-.0003 of an inch long and broad; cystidia subfusi- 
form, .002-.0024 of an inch long. 
Pileus 5-8 lines broad; stem 10-18 lines long, about 1 line thick. 
Mossy ground under spruce and balsam fir trees. Lake Pleasant. 
August. 
This species is very closely related to I. umboninota from 
which it may be separated by its smaller size, the chestnut tint of 
the cap, its hollow stem and smaller merely angular spores. 
Cystidia are more abundant. The species belongs to section 
Rimosi. 
Inocybe excoriata n. sp. 
PLATE O, FIG. 14-19 
Pileus fleshy, broadly conic, soon broadly convex, umbonate, 
fibrillose or fibrillose squamulose, somewhat silky or tomentose 
