NATURAL HISTORY SURVEY 47 



Lamellae distant, arcuate, strongly decurrent, white. 



Stem slender, commonly long in proportion to the breadth of 

 the pileus, colored like or a little paler than the pileus. 

 K Pileus 4 to 10 mm. broad; stem 2.5 to 5 cm. long, scarcely a 

 millimeter thick. Spores narrowly ellipsoid, 4 x 2 /A. 



Mossy borders of swamps, Millers; damp mossy places in ra- 

 vines, Glencoe. August. 



Omphalia scyphoides Fr. 



Pileus submembranous, plane and umbilicate or funnel-form, 

 often irregular or somewhat eccentric, even, silky, white. 



Lamellae narrow, close, decurrent, white. 



Stem short, stuffed, subvillose, white. 



Spores ellipsoid, 6 x 4 to 5 /A. Pileus 4 to 8 mm. broad; stem 

 8 to 16 mm. long. 



Among dead leaves and twigs in woods, Glen Ellyn. July. 

 Pileus fragile; stem solid or stuffed, sparsely (at the base closely; 

 villous. 



PLEUROTUS. 



Stem eccentric, lateral or none; epiphytal (very rarely growing 

 on the ground), irregular, fleshy or membranaceous. Spores 

 white (violet-tinted in P. sapidus). 



Stem eccentric 1 



Stem obsolete, or nearly so 5 



1. Lamellae adnexed, pileus dry P. ulmarius. 



1. Lamellae adnate, pileus viscid when young. .P. serotinus. 



1. Lamellae decurrent 2 



2. Lamellae distinct at the base 3 



2. Lamellae anastomosing at the base 4 



3. Pileus white or buff P. dryinus. 



3. Pileus fuliginous-cinereous P. salignus. 



4. Spores white P. ostreatus. 



4. Spores lilac'. P. sapidus. 



5. Pileus squamose, 2.5 to 10 cm. broad P. mastrucatus. 



5. Pileus villous, 2.5 to 5 cm. broad P. atrocaeruleus 



5. Pileus pruinose, 4 to 6 mm. broad P. applicatus. 



Pleurotus ulmarius Bull. (Plate V.) 



Pileus fleshy, compact, convex or nearly plane, glabrous, 

 moist, sometimes tinged with reddish, yellowish or brownish hues 

 and marked with livid spots, becoming darker and shining when 

 old; flesh pure white. 



Lamellae broad, emarginate or rounded behind, adnexed, 

 moderately close, white or whitish. 



Stem stout, solid, straight or curved, glabrous or partly or 

 wholly tomentose, whitish. 



Spores globose, 5 to 6 ft. Pileus 7.5 to 15 cm. broad; stem 2.5 

 to 7.5 cm. long, 12 to 20 mm. thick. 



