224 THE AGARICACEAE OF MICHIGAN 



dung be placed in a damp chamber, troops of this fungus will ap- 

 pear within 10-14 days. Larger specimens appear at first; succes- 

 sive plants appear smaller and smaller until they are often only 

 one or two millimeters in diameter and one or two centimeters high. 

 Just as there is much variation in the size of the fungus there is 

 wide variation in the size of the spores. Occasionally the speci- 

 mens are found with small spores 7-10x5-8 micr., as given by Sac- 

 cardo (Sylloge, Vol. 5, p. 1101). Usually, however, they average as 

 large as given in our description. Specimens of this plant have 

 been distributed in exsiccati under the name of G. ephemeras and 

 G. plicatilis. The plant figured by Buller as G. plicatiloides (Re- 

 searches in Fungi) is evidently G. radiatus. 



Section X. Hcmerohii. Pileus always glabrous or slightly prui- 

 nose with minute hairs. No universal veil. A few scurfy particles 

 may be found by the breaking of the cuticle or trama when the 

 pileus becomes plicate. 



212. Coprinus ephemerus Fr. 



Fries, Epicr., p. 252. 



Illustrations: Cooke, 111., PI. 685 f. 



Plates XLII and XLIII of this Report. 



PILEUS 1-2 cm. across, ovate, then campanulate, finally ex- 

 panded, often splitting and revolute, margin sometimes uneven, 

 striate, plicate when expanded, very thin, disk even or slightly ele- 

 vated. Yellowish brown to reddish bay at the disk, at first slightly 

 pruinose with minute hairs. GILLS linear, slightly adnexed or 

 barely reaching the stem, usually white at margin. STEM 3-6 cm. 

 high, 1-2 mm. thick, equal or slightly tapering upward, hollow, 

 white. SPORES 15-17 x 7-8 micr., black in mass. 



Common upon dung or freshly manured ground. 



In an examination of different exsiccati, we have found abundant 

 evidence of the truth of Saccardo's statement that many different 

 species have been confused under the name of G. ephemerus. 



We have found well-marked specimens of G. radiatus, G. plicatilis, 

 and G. spraguei all under the name of G. ephemerus. Even as we 

 have limited this species, there are many distinct forms which may 

 be readily distinguished. We have grown several of these varieties 

 from spores and have found them to be constant and, even in young 

 stages, the differences are often apparent to the naked eye. One 



