PLEUROTUS 441 



D . Pileus confluent with the excentric, or lateral stem, 

 dimidiate, sessile, or resupinate. 



Spores white, gill edge entire. 



Pleurotus FT. 

 (TrXevpov, side; ovs, ear.) 



Pileus fleshy, or submembranaceous, excentric, dimidiate, or re- 

 supinate. Stem excentric, lateral, or wanting; with or without a 

 ring. Gills sinuate, adnate, decurrent, or radiating from a central 

 point. Spores white, rarely pink, yellowish, lilac, or dingy; elliptical, 

 globose, subglobose, pip-shaped, oblong elliptical, cylindrical, or 

 reniform, smooth, granular, verrucose, or echinulate; continuous. 

 Cystidia present, or absent. Growing on wood, more rarely on the 

 ground, or on dung. 



I. P. entire, laterally extended, excentric, not 

 truly lateral. Lignicolous. 



A. Veil forming a ring. 



1433. P. corticatus Fr. (= Pkurotus dryinus (Pers.) Fr. sec. Quel.) 

 Boud. Icon. t. 76. Corticatus, possessed of a bark. 



P. 520 cm., whitish grey, sometimes becoming yellowish, covered with 

 dense grey down which separates into fioccose scales, very compact, 

 convex, then flattened, somewhat disc-shaped, horizontal, always 

 entire although excentric, rarely infundibulif orm ; margin involute, 

 often denticulate with the remains of the ring. St. 2-59 x 2-53 cm., 

 whitish, hard, rooted, more or less excentric, curved-ascending, squamu- 

 loso-fibrillose. Ring white, silky- floccose, moderately thick, ruptured 

 in a torn manner, adhering to the st. and the margin of the p., at 

 length vanishing. Gills white, becoming yellow when old, deeply de- 

 current, dichotomosely branched, anastomosing at the base, subdistant. 

 Flesh white, hard. Spores white, oblong, cylindrical, often slightly 

 curved and apiculate at the base, 13-15 x 4-5/x, or 9-10 x 3-4/x, 

 often with a large central gutta. Smell and taste pleasant, rather 

 strong. Edible. Caespitose. On trunks of ash, elm, lime, and apple* 

 Sept. Oct. Not uncommon, (v.v.) 



var. Albertinii (Fr.) Quel. (= Pleurotus corticatus Fr. var. tephro- 

 trichus Fr. sec. Quel.) Bres. Fung. Trid. t. 80, as Pleurotus 

 corticatus Fr. var. tephrotrichus Fr. 



J. Albertini, an early mycologist. 



Differs from the type only in its smaller size, p. 7-10 cm., in the 

 densely villose p., soon covered with subfuscous squamules, the hairy 

 stem, and villose edge of the gills. Solitary. At the base of fir trunks, 

 and on oak piles. July Sept. Uncommon. 



