MICROSCOPIC (II Mi V I I RS . 1 



Fig. 3. Gill trama — divergent type, as found in //. fuUginetu. 



ment but instead appear parallel in the sections. We have encountered 

 this situation to some extent in the trama of the type of //. eburneifor- 

 mis, except that here some indications of divergence were' observed, 

 and the central strand was more interwoven than parallel. Cons, 

 quently, it is important to section fresh material of Hygrophorus to be 

 sure that one's interpretation of the hvphal arrangement of the gill 

 trama is correct. 



2. In section Camarophyllopsis (Fig. 4) typically the hyphae of 

 the hymenophore are compactly as well as intricately interwoven and 

 are narrow — usually .5-10 /x in diameter but range from about 2 to 14 ^ 

 depending on the species. In several species, however, there is a Layer 

 of subparallel hyphae next to the subhymenium (sec //. colemannianus). 

 We believe this tendency has some significance as Ear as the evolution 

 of tramal types in Hygrophorus is concerned. Hosier has observed a 

 peculiar situation in //. bakeri and //. umbrinus in which there is, in 

 revived sections, a central strand of parallel hyphae flanked on either 

 side by interwoven elements. This is the opposite" of the //. colcnuin- 

 nianus type. In //. microsporias the gill hyphae are only somewhat 

 interwoven as viewed in mounts of revived material but definitely 

 interwoven as seen on sections of fresh specimens 



