THE POLYPORACEAE OP WISCONSIN. 147 



The pure white color, the viscid pileus, and the astringent excretion 

 are good distinguishing marks. 



Boletus Olintonianus Peck (Plate XVI, fig. 59; PI. XVII, fig. 59). 



Pileus convex, very viscid or glutinous, glabrous, soft, shining, golden 

 yellow, reddish-yellow or chestnut color, the margin thin, flesh pale- 

 yellow, becoming less bright or dingy on exposure to the air; tubes 

 nearly plane, adnate or subdecurrent, small, angular or subrotund, pale 

 yellow, becoming dingy-ochraceous with age, changing to brown or pur- 

 plish brown where bruised ; stem equal or slightly thickened toward the 

 base, straight or flexuous, yellow at the top, reddish or reddish-brown 

 below the annulus, sometimes varied with yellow stains, the annulus 

 white or yellow, persistent, forming a thick band about the stem ; spores 

 brownish-ochraceous, 10 to 11.4 microns long, 4 to 5 microns broad. 

 Pileus 5 to 10 cm. broad ; stem 5 to 12.5 cm. long, 8 to 19 mm. thick. 



Mossy or grassy ground in woods or open places, especially under 

 tamarack trees. 



This elegant Boletus has been collected at Madison, Beloit, Algoma 

 and Crandon, usually near or under tamarack trees. The largest speci- 

 men found at Crandon was 15 cm. in diameter, the stipe 12 cm. long 

 and 2 cm. thick. The pileus was first convex then concave above, yel- 

 low to chestnut, shining viscid; the margin thin becoming recurved. 

 Pores adnate, equal, angular, medium, yellow. Annulus whitish, thick 

 persistent. The stipe was yellow above, brownish beneath, brown- 

 spotted, but not always. The flesh yellowish, hyaline near the tubes; 

 the flesh as well as the pores changing to brown when bruised; how- 

 ever, the flesh changed only slightly. 



This species appears to be so much like B. elegans Schum., that it 

 might be called a variety. The chief difference is in the persistent an- 

 nulus. 



Boletus sphaerosporus Peck (Plate XVIII, fig. 62.) 



Pileus at first hemispherical then convex, glabrous, viscid, creamy- 

 yellow, becoming reddish-brown or chestnut color with age, flesh pale 

 yellowish-brown; tubes adnate or slightly decurrent, large, angular, 

 pale-yellow, becoming brown sometimes tinged with green; stem stout, 

 equal, even or slightly reticulated at the top, the membranous annulus 

 persists, sometimes partly adhering to the margin of the pileus ; spores 

 globose or broadly elliptical 7.6 to 8.9 microns long. 



