PRINCIPAL GROUPS OF PLANTS. 61 



pileus varies from whitish to a drab color, but the color of the 

 gills is at first pinkish and then of a brownish-purple, which is 

 an important character, the color being due to the spores. The 

 stipe is cylindrical and solid, and a little more than half way up 

 is furnished with a membranous band known as the ring. There 

 are no appendages at the base of the stipe, which appears to rise 



FIG. 36. Edible Boletus (Boletus edulis), an excellent edible mushroom found in woods 

 and openings in summer and autumn. The cap is 8 to 15 cm. wide, grayish-, yellowish-, or 

 brownish-red, sometimes paler toward the edge, smooth, and more or less convex; flesh 

 whitish or yellowish, or somewhat reddish just beneath the skin; stem white, stout, and 

 often bulbous. After Atkinson, "Studies of American Fungi." 



directly out of the ground. Before the pileus is fully expanded a 

 veil extends from its border to the stipe, which when ruptured 

 leaves a portion attached to the stipe, and it is this which consti- 

 tutes the ring. The ring shrinks more or less in older specimens, 

 but usually leaves a mark indicating where it has been formed. 



Poisonous Fungi. There are two of the poisonous group 

 of Fungi which are very common and which have some resem- 



