GILL FUNGI 



33 



Key to the Species 



1. Gills beneath the cap or lateral 



a. Stem distinct, excentric ; gills adnexed or sinuate P. uhnarhts 



b. Stem lateral or disappearing ; gills decurrent 



( 1 ) Cap horizontal or shelf-like 



(a) Spores white P. 



(b) Spores lilac-tinged against a white background P. 



(2) Cap more or less erect and spatula-like P. petaloides 



2. Gills on the upper side, i. e., the cap reversed P. applicatus 



ostreatus 

 sapidus 



Figure 20. Pleurotus ostreatus 



Pleurotus ulmarius Elm Cap 



Cap large, 8-15 cm. wide, white, whitish or tan, often brownish toward the 

 center, smooth, often cracked, usually convex, sometimes plane ; stem long and 

 stout often nearly central, 5-12 cm. by 2-3 cm., white or tan, smooth or hairy 

 toward the base, solid, elastic, often curved ; gills adnexed or sinuate, whitish, 

 broad close ; spores globose, 5-6/x. The name refers to its fondness for the elm. 



