PLEUROTUS. 377 



On branches. 



Stem reduced to a white downy tubercle ; flesh of pileus 

 thin, pileus exactly lateral, semicircular, horizontal, plane,, 

 even, downy, grey, 4-5 lines broad ; flesh very thin, rather 

 gelatinous, diaphanous. (Fries.) 



Pleurotus lauro-cerasi. B. and Br. 



Pileus up to 1J in. across, flesh thin, equal, sessile, hori- 

 zontal and attached by a narrow base, more or less circular 

 in outline, or shell-shaped, silicate, brownish; gills very 

 broad at the middle, narrowed to both ends, rather thin, 

 connected by veins, whitish, margin wavy ; spores elliptical, 

 apiculate, 8 X 5 /z. 



Agaricus (Pleurotus) lauro-cerasi, B. and Br., Ann. Nat. 

 Hist., no. 1854; Cke., Hdbk., p. 108; Cke., Illustr., pi. 242A. 



On stems of cherry laurel. 



Pileus rather more than 1 in. across; the cuticle is ex- 

 tremely thin, and gives way at the furrows, so as to expose 

 the substance of the pileus. (B. & Br.) 



Pleurotus tremulus. Fr. 



Pileus about | in. across, flesh thin, dimidiate, somewhat 

 horizontal, reniform, plane, depressed and often villous 

 behind, the remainder glabrous, even, greyish-brown becom- 

 ing pale, hygrophanous ; gills adnate, appearing decurrent 

 from the depression of the pileus, determinate, narrow, 

 rather distant, very unequal, grey; stem distinct, exactly 

 lateral, vertical or slightly ascending, round, about ^ in. 

 long, about two lines thick, sometimes very short, dilated 

 upwards, attached by the fibrillose base to mosses. 



Agaricus (Pleurotus) tremulus, Fries, Epicr., p. 135; Cke., 

 Hdbk., p. 108 ; Cke., Illustr., pi. 242u. 



On musses and on the ground. 



More variable than neighbouring species. Entire fungus 

 grey. (Fries.) 



Distinguished from P. tremulus by the presence of a 

 distinct stem. 



Pleurotus acerosus. Fr. 



Pileus up to 1 in. across, almost membranaceous, reniform 

 or almost orbicular, plane, somewhat lobed, striate, hygro- 

 phanous, greyish, when dry with a white silkiness ; stem 



