318 SECTION HYGROPHORUS 



Spores 7-9 X 4.5-5 /x, ellipsoid to somewhat ventricose-ovate, 

 hyaline, pale yellowish in Melzer's solution; as revived in Melzer's they 

 are seen to have a slightly thickened wall. Basidia 46-55 X 8-9 /x, 

 4-spored, clavate, and with long often flexuous pedicels. Pleurocystidia 

 and cheilocvstidia not differentiated. Gill trama with a subparallel 

 central strand of narrow hyaline hyphae which on either side diverge 

 toward the subhymenium. Cuticle an undifferentiated cutis, hyphae 

 repent, similar to those of the pileus, non-gelatinous. No hypodermium 

 differentiated. Pileus trama intricately interwoven, neither strikingly 

 radial nor periclinal. Clamp connections present on the surface hyphae 

 of the pileus. 



Habit, Habitat, and Distribution — Gregarious under Populus 

 trichocarpa, Thuja plicatilis, Tsuga heterophylla, and Pseudotsuga 

 taxifolia; Nisqually River, Mt. Rainier National Park, Wash., August; 

 also Europe. 



Material Studied — Washington: Smith 30480. 



Observations — The slight stickiness of the pileus is similar to that 

 of wet specimens of Inocybe geophylla and is not caused by gelatinous 

 hyphae. Hence the statement of Kiihner and Romagnesi (1953, p. 58) 

 applies to our collection. H. saxatilis and H. karstenii f. minor are 

 closely related but distinct. The former has a truly gelatinous pellicle 

 as well as differently colored gills. H. karstenii f. karstenii is a much 



Fig. 99. H. karstenii f. minor 



