4s THE CHICAGO ACADEMY OF SCIENCES 



On trunk of Aar Negundo, Wheaton. October, 1S96. Pileus 

 elliptical. 27 x 20 cm. in the largest specimen. On living trunks 

 of Limn*. River Forest and Bowmanville. Often 7 to 20 meters 

 from the ground. 



Pleurotus serotinus Fr. 



Pileus fleshy, compact, convex or nearly plane, viscid when 

 young and moist, dimidiate, reniform or sub-orbicular, solitary or 

 cespitose and imbricated, variously colored, dingy-yellow, red- 

 dish-brown, greenish-brown or olivaceous, the margin at first 

 involute. 



Lamellae close, determinate, whitish or yellowish. 



Stem very short, lateral, thick, yellowish beneath and minutely 

 tomentose or squamulose with blackish points. 



Spores elliptical, 5 x 2.5 /x. Pileus 2.5 to 7.5 cm. broad. 



Reported from woods at Bowmanville by Bertolet, Harper 

 and Pepoon. Autumn. 



Pleurotus dryinus Fr. 



Pileus white or buff, convex or expanded, more or less depressed 

 in the center, margin floccose. becoming floccose-sealy. 



Lamellae white becoming tinged with yellow in age, decurrent 

 in fines clown the stem, not crowded. 



Stem varying from nearly central to definitely lateral, smooth, 

 white, tough, fibrous: veil floccose. 



Pileus 5 to 10 cm. broad; stem 2 to 12 cm. long, 1 to 2 cm. 

 thick. 



Knot-hole in a log, River Forest. October. 1003. 



The upper portion of the stem is pruinose between the decur- 

 rent striae of the lamellae. Lamellae shining-white, nut anastom- 

 osing behind. I find no record of the size of the spores of this 

 species. Cooke's figure. Illust. PI. 220. shows them to be narrowly 

 oblong. In our plant they are oblong, 11x4 u. The pileus 

 5 to 8 cm. broad; the stem 5 cm. long. 1 to 2 cm. thick. 



Pleurotus salignus Schw. 



Pileus fleshy, compact, sp .at dimidiate, horizon- 



tal, at first pulvina* :i, afterwards the disk depressed, some- 



what strigose, fuliginous-cinereous, sometimes ochraceous. 



Lamellae decurrent. some of them branched, eroded, distinct 

 at the base, subconcolorous with the pil< 

 in short, tomentose. 



On decaying wood of Ulmus an , W :,• aton. October. 



Pileus 7.5 to 12.5 cm. broad, both it and the lamellae tougher 

 than those of P. ost Lamellae pallid. a1 b ochraceous, 



decurrent, not anastomosing behind. -lowly, 



lasting three or four weeks. Spores abundant, pure white, 9 to 

 13 x 5 to 6 ft. 



