164 SECTION HYGROCYBE 



brown" ( blackish brown ) on disc and "buffy brown" ( olive brown ) on 

 margin, fading to dingy gray-brown, moist and hygrophanous, squamu- 

 lose (especially along the margin), when moist opaque to translucent 

 striate, margin often crenate. Context brittle, soft, watery; odor and 

 taste mild. 



Lamellae arcuate to subdecurrent, in age at times with decurrent 

 lines, near "drab gray" when young but margins pallid, subdistant, 

 broad or medium broad, often intervenose to subporoid, edges even. 



Fig. 47. 



H. atro-olivaceus 



Stipe 3-5 cm long, 5-12 mm diameter at apex, evenly colored and 

 a paler gray-brown than the pileus, usually compressed, naked and 

 moist. 



Spores 5-6 X 3.5-4.5 /*, ellipsoid to subglobose, smooth, hyaline in 

 KOH and Melzer's reagent. Basidia 28-34 X 6-7 fx, flexuous at base, 

 4-spored. Pleurocystidia and cheilocystidia none. Gill trama parallel, 

 hyaline in KOH, in Melzer's reagent dark amber brown from granules 

 within the cells which stain dark. Pileus trama similar to gill trama in 

 color in KOH and Melzer's reagent, cuticle a trichodermium (the ele- 

 ments grouped to form fascicles which are the squamules). Pileus 

 trama of interwoven hyphae, more or less radially disposed. Clamp 

 connections none. 



Habit, Habitat, and Distbibution — Caespitose in woods, Michi- 

 gan and Washington, July-September. 



Matebial Studied— Michigan: Smith 26159, 37561, 39418 (type, 

 from Pellston, Mich., Aug. 10, 1952), 42092. Washington: Smith 31052, 

 31744, 40145. 



Obsebvations — The lack of clamp connections, the faded, squamu- 

 lose pileus, dark gray-brown colors, and reaction of the contents of the 

 hyphae to Melzer's reagent, along with the small spores, are distinctive. 



