34 GENERAL CONSIDERATIONS 



Usually species of Hygrophorus grow in the leaf mold which cov- 

 ers the soil. It is, then, as Ramsbottom (1953) says, more logical to 

 relate their occurrence and distribution to the nature of the humus 

 rather than of the soil itself, and, of course, the kind of humus in turn 

 is dependent on the vegetation which produced it. Thus it is useful to 

 speak of vegetation types as habitats — deciduous woods, coniferous 

 woods, mixed woods, or grasslands (lawns, meadows, pastures) — 

 rather than soil-types. 



Although animal dung provides a substratum for certain agarics, 

 we know of no record of such habitation for any species of Hygropho- 

 rus. 



GEOGRAPHIC CONSIDERATIONS 



Any effort to present a comprehensive and precise picture of 

 geographic distribution of agarics is beset with problems arising out of 

 their erratic appearance. The occurrence of mushroom crops in any 

 given area is so sporadic, unpredictable, and often brief that conclu- 

 sions from reports are hazardous. There is also the problem of agree- 

 ment as to species identity. Based on the records at hand, however, 

 some tentative generalizations are offered. 



Field studies undertaken in the tropics by Murrill (see 1916) and 

 by Dennis ( 1953 ) have yielded collections of some species of Hygro- 

 phorus which, to date, have not been found in temperate North Amer- 

 ica. For example, H. subpratensis, found in Cuba and St. Johns, has not 

 yet been reported for Canada or the continental United States. Den- 

 nis (1953) has reported Hygrophorus species from Trinidad, including 

 H. bakeri, buccinulus, cr emeus, umhrinus, cinerascens, erinensis, fir- 

 mus (and its varieties militaris, Occident alls, purpureus, trinitensis) , 

 luteistipes, papillatus, and troyanus. None of these has as yet been 

 reported for temperate North America. These, so far as we now know, 

 are tropical species. It is quite within the realm of possibility that at 

 least some of these so-called tropical species may yet be discovered in 

 Canada or the United States. In this connection, it is interesting to 

 observe that H. cantharellus occurs in eastern temperate North 

 America, and also in Jamaica, Trinidad, and Venezuela. Murrill's H. 

 flavoluteus, originally described from Jamaica, was subsequently col- 

 lected in Mexico. The type of H. hondurensis was found in British 

 Honduras, and is now known also from Florida, Michigan, Washington, 

 and from Trinidad. H. subaustralis, the type from North Carolina, has 

 been collected by Dennis in Trinidad. Hygrophorus subflavidus, the 



