S14 THE AGARICACEAE OF MICHIGAN 



Key to the Species 



(a) Plant wholly white, 

 (b) Gills broad. 



(c) Stem tubular; plant snow-white. 879. 0. gracillima Fr. 

 (cc) Stem solid; plant soon dingy-white. 878. 0. albidula Pk. 

 (bb) Gills rather narrow. 



(c) Gills crowded; plant pure white. 869. 0. scyphoides Fr. 

 (cc) Gills moderately close; plant dull white. 870. 0. scyphi- 

 formis Fr. 

 (aa) Plant not wholly white, 

 (b) Pileus viscid, 

 (c) Gills lilac; pileus greenish-yellowish. 872. 0. lilacifolia Pk. 

 (cc) Gills whitish; pileus pale grayish-brown. (See 834. Mycena 

 vulgaris Fr.) 

 (bb) Pileus not viscid. 



(c) Pileus yellowish, orange or reddish. 



(d) Stem date-brown, horny; on coniferous wood; gills very 



veiny. 883. 0. campanella Fr. 

 (dd) Stem not date-brown and horny. 



(e) Gills white or cream-colored; on mosses. 



(f) Pileus 10-20 mm. broad; convex. 882. 0. ftbuloides Pk. 

 (ff) Pileus 3-8 mm. broad, cucullate. 880. O. fibula Fr. 

 (ee) Gills not white. 



(f) Pileus brick-red to reddish-brown. 873. O. pyxidata Fr. 

 (ff) Pileus olivaceous-yellowish; stem dusky yellowish. 871. 

 O. olivaria Pk. 

 (cc) Pileus with grayish, fuscous or brown shades. 



(d) Pileus 3-7 mm. broad, whitish except the fuscous-brown 



center. 881. O. schwartzii Fr. 

 (dd) Pileus usually larger. 



(e) Gills broad, crowded; pileus and stem 'dark, umber-fuscous 



to blackish. 884. O. umbratilis Fr. 

 (ee) Gills rather narrow, 

 (f) Pileus dotted with scurfy-blackish points; on sphagnum. 



877. O. gerardiana Pk. 

 (ff) Not with blackish points, 

 (g) On decaying wood, logs, stumps, etc. 

 (h) Pileus rugose, brown; flesh emitting watery juice 



when cut. 874. O. rugosodisca Pk. 

 (hh) Pileus even, ashy to smoky, non-hygrophanous. 

 875. O. epichysium Fr. 

 (gg) On the ground, pileus hygrophanous, substriate; gills 

 subdistant. 876. O. onisca Fr. 



Section I. Collybiariae. Margin of pileus at first incurved. 



* Gills narrow; crowded, close or subdistant. 



869. Omphalia scyphoides Fr. 

 Syst Myc, 1821. 



Illustrations: Fries, Icones, PI. 75, Fig. 2. 

 Patouillarcl, Tab. Analyt, Xo. 419. 



"PILEUS 4-S mm. broad, umbilicate then infundibuliform, often 



