NATURAL HISTORY SURVEY 65 



On dead leaves, twigs, etc., in woods, Glen Ellyn. July, 

 August. 



The plants so referred have the pileus plicate-striate only 

 toward the margin, while the coating of the stem is of the character 

 of matted tomentum rather than "velvety." This coating is 

 thinner and paler toward the apex. The pileus is 12 to 25 mm. 

 broad; stem 5 to 7.5 cm. long, about 2 mm. thick; spores pip- 

 shaped, 6 to 7 x 4 fj.. 



Marasmius calopus Pers. 



Pileus a little fleshy, tough, convex-plane or depressed, even, 

 at length rugose. 



Lamellae emarginate-attached, thin, white. 



Stem hollow, equal, glabrous, shining, reddish-brown. 



Spores ellipsoid, 7 x 4 /t*. Pileus 2 to 3.5 cm. broad; stem 

 5 to 7.5 cm. long. 



On dead leaves and sticks in woods. July and August. Com- 

 mon. Pileus watery-white when wet ; campanulate then flattened, 

 stem whitish above in young plants; odor none. Spores ellipsoid, 

 somewhat apiculate at one end, 6 to 7 x 3 to 4 /x,. 



Marasmius siccus Schw. 



Pileus membranaceous, convex or campanulate, dry, glabrous, 

 plicate-sulcate, ochraceous-red, the disk a little darker. 



Lamellae attenuate-attached or nearly free, distant, whitish. 



Stem hollow, horny, glabrous, shining, blackish-brown. 



Pileus 1.3 to 1.8 cm. broad; stem 5 to 7.5 cm. long. 



Among dead leaves in woods. July and August. Frequent. 

 After protracted rains the plants are very large, up to 3 cm. in 

 diameter. M. campanulatus Peck, is a synonym. A minute 

 form with the pileus only 2 to 6 mm. broad was found at River 

 Forest in June, 1902, growing on dead ligules of living culms of 

 Poa pratensis. No spores were found. 



Marasmius rotula Fr. 



Pileus hemispherical, umbilicate and minutely umbonate, 

 plicate, smooth, margin crenate, white or pale-buff with a dark 

 umbilicus. 



Lamellae broad, distant, attached to a free collar behind, 

 pallid-white. 



Stem slender, horny, slightly flexuous, white above, then 

 tawny, deep shining brown at the base, striate, fistulose. 



Pileus 2 to 6 mm. broad. 



On twigs, leaves, etc., June to September. Our most common 

 species. During dry weather the plants shrivel and dry up so 

 that they are scarcely noticed, even in localities where they are 

 abundant. After a heavy rain they may be seen in countless 

 numbers. Pileus 4 to 8 mm. broad; stems 2.5 to 5 cm. long, very 

 slender. Specimens collected in Schoolcraft County, Michigan, 

 growing upon dead prostrate trunks were 2.5 cm. in diameter. 

 With us the dimensions given above are rarely exceeded. 



