796 THE AGARICACEAE OP MICHIGAN 



848. Mycena immaculata Pk. 

 N. Y. State Mus. Kep. 38, 1885. 



PILEUS 4-8 mm. broad, conical or subhemispherical, glabrous, 

 slightly striate on the margin, pure white. FLESH membrana- 

 ceous. GILLS adnate or uncinate-deeurrent, moderately broad, 

 distant, white. STEM 1.5-3.5 cm. long, scarcely .5 mm. thick, 

 slender, pellucid-white, glabrous, generally villose-strigose at the 

 base, slightly thickened at apex. SPORES oblong or cylindrical, 

 7.5-9 x 3 micr. 



On mosses and fallen leaves on the ground. Bay View. August. 



This seems to differ sufficiently from M. lacteus Fr. which has 

 crowded narrow gills; the latter grows caespitosely on wood ac- 

 cording to Stevenson (British Fungi), while Fries (Epicrisis) says 

 it is generally found ou the ground. M. minutula Pk. and M. crys- 

 tallina Pk. should be compared with it. 



Section VII. Rigipedes. Stem firm, rigid, somewhat tough, juice- 

 less, somewhat strigose and rooted at the base. Gills becoming 

 tinged with gray, flesh color, fuscous, etc. Pileus not hygrophanous. 



Tough, persistent, inodorous, normally growing on wood and 

 caespltose. 



Fries originally (Syst. Myc, Vol. I, p. 13) included some of 

 the following species under M. palericulata. In Epicrisis he divided 

 the latter into a number of species. As Fries did not consider 

 any microscopic characters, some of these species have been much 

 misunderstood, and even today no clear account can be given by 

 which they can, with entire certainty, be separated. I have at- 

 tempted below, by using such critical studies as others have made 

 with the microscope, and adding my own, to separate those which 

 have been found in my collecting by using the characteristics of 

 the spores and cystidia. As Fries pointed out (Epicrisis, p. 104), 

 the color, especially of the stem, is very deceptive in many of these 

 species, and cannot be relied on to any great extent for their 

 separation. 



