1914] 



BURT — THELEPHORACEiE OF NORTH AMERICA. I 187 



substratum. If the description fails to give the color as exactly 

 as if it had been noted by comparison with such a standard 

 work as Ridgway's 'Color Standards' or Saccardo's 'Chromo- 

 taxia/ then it is inferior to the specimen; if the description con- 

 tains no information as to whether the basidia are simple or 

 cruciate, making up the whole hymenium or arranged side by 

 side with other organs of characteristic form, standing directly 

 on the substratum or separated from it by densely or loosely 

 interwoven hyphse or other form of subhy menial layer; — if it 

 does not contain all this information in exact terms and as much 

 in addition as the specimen itself could afford, then it is an im- 

 perfect description of the species. It may be so imperfect that 

 a dozen different species of fungi could be assembled, to any 

 one of which it would apply as well as to any other, as is the 

 case with the supposedly common and cosmopohtan Corticium 

 lacteum and C. calceum. Pubhshed exsiccati probably contain 

 the full dozen under each of these names. 



In the case of resupinate Hymenomycetes, types and authentic 

 specimens of the species are of the highest importance to supple- 

 ment the prevailingly imperfect descriptions with full and 

 exact data. Hence, the types of fungi on which the descriptions 

 are based and the authentic specimens from the authors of the 

 species are of importance in proportion to the degree in which 

 these plants may yield data not afforded by the descriptions and 

 existing illustrations of the species. In the case of the resupi- 

 nate Hymenomycetes, the early descriptions are of slight prac- 

 tical value except as they are backed up by types and specimens 

 from their authors. For this reason, if there had been no 

 other, the International Botanical Congress, at Brussels, acted 

 for the best interests of mycology in fixing the beginning of the 

 naming of Hymenomycetes with the pubhcation of Fries' 'Sys- 

 tema Mycologicum,' — the time when the preservation of types 

 and authentic specimens of such fungi in herbaria became so 

 prevalent that it was possible for later mycologists to distin- 

 guish the resupinate species by taking the trouble to study the 

 types, if authentic specimens could not be obtained. 



My method of becoming acquainted with our described 

 species of Thelephoracece has been to study and arrange by 

 species in my herbarium the specimens as they have accumu- 



