46 CIRCULAR 143, U. S. DEPARTMENT OF AGRICULTURE 
the annulus; the annulus is variable, sometimes persisting as a narrow ring 
and again appearing as a broad collar. 
The cap is 3 to 4 inches broad; the stem is 2% to 8 inches high. 
This is an excellent edible species of wide geographic distribution, occurring 
commonly in pine woods. 
A very similar species is Boletus subluteus, which is ornamented with dots 
both above and below the annulus. This fungus also is considered edible. 
BOLETUS GRANULATUS 
The cap is convex or nearly plane, color variable, when moist viscid and 
reddish brown, paler and yellowish when dry; viscid or glutinous; the flesh 
is pale yellow; the tubes are short, adnate, yellowish, mouths granulated; 
the stem is pale yellowish, dotted above. 
A nearly related species, Boletus brevipes, is distinguished from B. granu- 
latus by a shorter stem and the absence or indistinctness of granulations 
on the mouths of the tubes and stem. 
Ficgurp 41.—Boletus felleus (form with nonreticulate stem) 
BOLETUS FELLEUS. BITTER BOLETUS 
(Fig. 41) 
The cap is convex or nearly plane, firm, becoming soft, color variable, pale 
yellowish, grayish brown, reddish brown, or chestnut; the flesh is white, 
often changing to flesh color when wounded, and of bitter taste; the tubes 
are adnate, long, depressed around the stem, mouths angular, white, beccm- 
ing tinged with flesh color; the stem is similar in color to the cap, but paler, 
variable, long or short, equal or tapering upward, sometimes bulbous, 
reticulated above. 
The cap is 8 to 4 inches broad; the stem is 2 to 8 inches long. 
This is a common and widely distributed species. It is exceedingly con- 
spicuous on account of its color, size, and solidity; though not poisonous, it is 
very bitter. 
A variety, Boletus felleus obesus, attains a size of about a foot in diameter 
and has coarse reticulations on the stem. 
