litis 



THE AGARICACEAE OF MICHIGAN 



Section If. Dimidiati. Pileus lateral, not marginate behind, 

 not at lirst resupinate, sessile or continuous with the stem-like base. 



706. Pleurotus serotinus Fr. (Edible) 



S.vst. Myc, 1821. 



Illustrations: Hard, Mushrooms, Fig. 24, p. 161, 1908 (as P. 

 serotinoides Pk.). 

 Cooke, 111., PI. 258. (Without the olive tints, etc.) 

 Patouillard, Tab. Analyt., No. 629. 



PILEUS 3-8 cm. broad, campact, convex or nearly plane, lateral. 

 orbicular, dimidiate or reniform, with <i gelatinous pellicle which 

 becomes viscid when moist, olivaceous-umber but varying to yellow- 

 ish greenish or brown, surface often covered with a short, dense 

 tomentum. FLESH white, thick, firm. GILLS abruptly subde- 

 current, thin, broad, narrow in front, close, whitish or tinged ochra- 

 ceous or tan. STEM very short, lateral, continued above with the 

 pileus, stout, 5-20 mm. long, 8-10 mm. thick, yellowish beneath, sub- 

 tomentose or dotted with brown or blackish scales, solid. SPORES 

 minute, linear-oblong, slightly curved, 4-6x1-1.5 micr., smooth, 

 white in mass. CYSTIDIA fusiform, yellowish, about 25 micr. 

 long. BASIDIA 4-spored. ODOR and TASTE none. 



(Dried: Colors similar to those of fresh condition, i 



Caespitose, imbricated, often laterally connate, sometimes soli- 

 tary. On fallen elm trunks, or dead branches of various frondose 

 trees. Southern Michigan; probably throughout the State. August- 

 November. Frequent locally. 



The mode of growth is similar to that of Claudopus nidulans, but 

 lacks the odor of the latter and is usually more compact and the 

 colors are dingy. The spores usually found deposited on the lower 

 pilei from those above are white. The tomentum on the pileus 

 oil en breaks up into punctate scales. The short stem, seen only 

 below, has a yellow-tomentose covering. It may appear in consider- 

 able quantity on a single tree trunk. 



