THE POLYPOBACEAE OF WIS^CONSIN. 123 



Boletus cyanescens Bull. 



Pileus convex or nearly plane, opaque, floceose-squamose or covered 

 with an appressed tomentum, pale-buff, grayisli-yellow, alutaceous or 

 somewhat brown, flesh rigid, white, quickly changing to blue where 

 wounded; tubes free, white, becoming yellowish, the mouths minute, 

 round, changing color like the flesh, stem ventricose, villose-pruinose, 

 stuffed, becoming cavernous, contracted and even at the top, colored 

 like the pileus ; spores subelliptical 10 to 12.5 microns long, 6 to 7.5 

 microns broad. Woods and open places. 



Localities : Hazelhurst, Crandon, Star Lake, Shanagolden, and Blue 

 Mounds. The largest measured about 9 cm. in diameter ; the stipe was 

 8 cm. long, and 2 cm. thick. The color was grayish-yellow throughout, 

 flesh whitish. The flesh, tubes and stipe change color immediately on 

 being touched. At first the injured spot becomes pale violet, then red- 

 dish violet, then of a deep prussian blue. This blue finally fades to a 

 pale greenish-yellow and sometimes disappears entirely. 



This species is easily recognized by the color changes and the cavern- 

 ous stuffed stipe. 



B. Hyporhodii. Tubes adnate, wMtish, becoming flesh-colored from 



the spores. 



Boletus felleus Bull. (Plate XXIV, fig. 83; Plate XXV, fig. 83.) 



Pileus convex or nearly plane, firm, becoming soft, glabrous, even, 

 variable in color, pale-yellowish, grayish-brown, yellowish-brown, red- 

 dish-brown or chestnut, flesh white, often changing to flesh-color where 

 wounded, taste bitter ; tubes adnate, long, convex, depressed around the 

 stem, their mouths angular, white becoming tinged with flesh-color; 

 .stem variable, equal or tapering upward, short or long, sometimes bul- 

 bous or enlarged at the base, subglabrous, generally reticulated above, 

 colored like or a little paler than the pileus; spores oblong-fusiform, 

 flesh-colored, 12.6 to 17.6 microns long, 4 to 5 microns broad. 



Quite common in summer; the largest and most abundant species 

 about Madison, usually in openings in the woods. Peck (21, 2, 8, p. 

 154) says it is easily recognized by its bitter taste. Many of our speci- 

 mens have a mild taste, while others are quite bitter, but they all agree 

 well with the description otherwise. When dry, the grayish-brown cut- 

 icle becomes brittle. The flesh remains whitish and is soft and cottony 

 when dry. The tubes change to a rust color when wounded; the flesh 

 is unchangeable. 



