216 SECTIOS HYGROCYBE 



forming the viscid pellicle. H. purus has much the stature of H. calyp- 

 traeformis, but its white pileus and glutinous stipe at once distin- 

 guishes it. Peck (1907) says that H. cahjptraeformis var. niveus Cke. 

 scarcely differs from H. purus, but we found no cystidia on Peck's type. 



125 



Hygrophorus singeri Sm. & Hes. var. singeri 



Svdowia 8: 331. 1954 



Hygrocybe singeri (Sm. & Hes.) Singer, Svdowia 11: 355. 1957. 



Pileus 1-3 cm broad, conic, becoming broadly conic, color reddish 

 orange to yellow, translucent-striate to disc, blackening in age, gla- 

 brous, slimy-viscid. Context very soft, greenish yellow, blackening 

 when cut or bruised; odor and taste not distinctive. 



Lamellae ascending and attached at very apex of stipe, pale 

 orange when young and finally greenish yellow, blackening where 

 bruised, close, broad, 2 tiers of lamellulae. 



Stipe 4-6 cm long, 3-5 mm thick, equal, pale orange-yellow be- 

 coming greenish yellow, blackening where bruised, slimy-viscid over 

 entire length (as in H. laetus). 



Spores 9-12 X 5-6 /x, elliptic in face view, in side view slightly 

 bean-shaped, smooth, yellowish in Melzer's solution. Basidia 36-42 x 

 9-11, 4-spored. Pleurocystidia and cheilocystidia none. Gill trama 

 parallel. Cuticle a gelatinous zone of narrow, repent hyphae (an 

 ixocutis). No hypodermium differentiated. Pileus trama of radial 

 hyphae. Clamp connections present. Stipe with narrow hyphae 

 (3-5 /x), gelatinous in KOH and present as an outer layer. Clamp 

 connections present. 



Habit, Habitat, and Distbibution — Scattered on a wet bank 

 under herbaceous plants, Oregon, Washington, Michigan, Mexico, and 

 Argentina. 



Matebial Studied — Michigan: Smith 43520, 43618, 49825. obe- 

 gon: Smith 19162 (type, from East Fork, Salmon River, Mt. Hood, 

 about 4300 ft.), 19606. Washington: Stuntz, Mt. Rainier National 

 Park, Oct. 2, 1952. Mexico: Singer M 1538a. abgentina: Singer M15. 



Obsebvations — This species is obviously in the H. conicus series, 

 but the character of the viscid stipe is so unusual and striking that it 

 cannot be regarded as other than a major character. One frequently 

 finds specimens of H. conicus in which the stipe is soft to the touch 

 and hence subviscid (or even doubtfully viscid in wet weather). 

 These forms, however, are not to be confused with H. singeri. The 

 latter often fruits during dry weather and yet the stipe is as viscid as 



