304 NORTH AMERICAN FLORA [VoLumE 9 
29. CREPIDOPUS (Nees) S. F. Gray, Nat. Arr. Brit. Pl. 1: 616. 
1821. 
Agaricus § Crepidopus Nees, Syst. Pilze Schw. 195. 1817. 
Pileus fleshy, putrescent, usually flabelliform in general outline: lamellae conspicuously 
decurrent: spores hyaline or becoming lilac-tinted: stipe eccentric or lateral, solid, sometimes 
much reduced: veil none. 
Type species, Agaricus ostreatus Jacq. 
Species occurring in temperate North America, 
Pileus minute, 2-4 mm. broad. 1. C. minutus. 
Pileus much larger, 2.5-12 cm. broad. : 
Pileus dingy-yellow to olivaceous; spores 5 X 2.5 yw. 2. C. serotinus. 
Pileus usually white or whitish, or with brownish hues; spores 7-11 X 
bb 
Stipe typically short and conspicuously hairy. 3. C. ostreatus. 
Stipe typically longer and glabrous, but varying toward that of the . 
above species. 4. C. cornucopiae. 
Species occurring in tropical North America. : 
Pileus becoming reddish on drying; lamellae very distant and interveined; 
stipe very short, lateral. 
Pileus white or whitish, often becoming yellowish on drying. 
Pileus 2-4 cm. broad; stipe 4-8 mm. long. 
Pileus 4-6 cm. broad; stipe 1-5 cm. long. 
Lamellae narrow, crowded; stipe 4-5 em. long. 
Lamellae rather broad, subdistant. 
Stipe glabrous, 1-2 cm. long. 
Stipe tomentose, 2.5-5 em. long. 
. hemiphlebius. 
. Lugeniae. 
. caveatus. 
. commiscibilis. 
. connatus. 
oR ND wr 
AQ ANA 
1. Crepidopus minutus (Peck) Murrill. 
Pleurotus minutus Peck, Ann. Rep. N. Y. State Mus. 55: 949. 1902. 
Pileus resupinate or reflexed with age, reniform or suborbicular, the center often de- 
pressed, 2-4 mm. broad; surface white, flocculose-pruinose, margin involute: lamellae unequal, 
decurrent, distant, very narrow, white or whitish: stipe short, eccentric, curved, pruinose, 
whitish, whitish-mycelioid at the base, 2 mm. long. 
TypE LocaLity: Loon Lake, New York. 
Hasitat: On rotten birch wood. 
DISTRIBUTION: New York. 
2. Crepidopus serotinus (Schrad.) Murrill, Mycologia 4: 216. 
1912. 
Agaricus serotinus Schrad. Spic. Fl. Germ. 130. 1794. 
Agaricus serotinoides Peck, Ann. Rep. N. Y. State Cab. 23: 86. 1872. 
Pleurotus serotinus Quél. Ench. Fung. 149. 1886. 
Pileus fleshy, compact, convex or nearly plane, dimidiate-reniform or suborbicular, 
solitary or cespitose and imbricate, 2.5-7.5 cm. broad; surface viscid when young and moist, 
variously colored, dingy-yellow, reddish-brown, greenish-brown, or olivaceous, margin at 
first involute: lamellae close, determinate, whitish or yellowish: cystidia 11-13 uw thick, with 
yellowish-brown sap; spores minute, ellipsoid, 5 X 2.5 4: stipe very short, lateral, thick, 
yellowish beneath and minutely tomentose or squamulose with blackish points. 
TYPE LOCALITY: Germany. 
Hasirat: Dead trunks of birch, beech, and other deciduous trees. 
DISTRIBUTION: Greenland to North Carolina and west to British Columbia and Washington; 
also in Europe. : 
ILLUSTRATION: Cooke, Brit. Fungi pl. 258 (284) B. 
Exsiccati: Ellis & Ev. N. Am. Fungi 3504; Underw. & Cook, Ilust. Fungi 2. 
3. Crepidopus ostreatus (Jacq.) S. F. Gray, Nat. Arr. Brit. Pl. 1: 
616. 1821. 
Agaricus ostreatus Jacq. Fl. Austr. 2: 3. 1774. 
Pleurotus ostreatus Quél. Champ. Jura Vosg. 77. 1872. 
Crepidopus subsapidus Murrill, Mycologia 4: 216. 1912. 
; Pileus fleshy, soft, convex or slightly depressed behind, subdimidiate, often cespitose- 
imbricate, 5-15 cm. broad; surface moist, silky to glabrous, white, whitish-cinereous, or brown- 
ish: context white, mild, edible; lamellae broad, decurrent, stbdistant, anastomosing at the 
