PREFACE. 



The present book is an outgrowth of a translation of the keys in the origi- 

 nal eight volumes of Saccardo's "Sylloge Fungorum." This translation was 

 mimeographed and bound for the use of classes in mycology. It immediately 

 proved so convenient and usable that the preparation of a complete guide to 

 the fungi was begun the same year. Many things have occurred during the past 

 two years to delay the completion of the guide until this time. In its present 

 form, the book is based upon Saccardo's great work, though in certain groups 

 other authors have been followed, and in some cases, the discomycetes and 

 lichens, the treatment amounts almost to a revision. The arrangement of the 

 orders and families is different in a large measure, and in the distribution of 

 the lichens is original. No attempt has been made to revise the genera, except 

 v'here the treatment had lagged behind current practice, as is particularly true 

 of the lichens. In some cases, genera have been included in others, but this is 

 done only for the sake of the beginner, when the descriptions reveal no differences, 

 and is by no means intended as a revision. 



Questions of nomenclature have necessarily been left largely to one side, 

 but no hesitation has been felt in making certain corrections. These have dealt 

 mostly with mistaken or neglected transliteration, and with faulty composition. 

 A considerable number of sesquipedalian words have been shortened, and the 

 greater number of hybrid names have been corrected. These corrections have 

 been made in such a way as to retain as much of the original name as possible. 

 Corrections are indicated by the sign t with the original form in parenthesis 

 below. New genera are designated by an asterisk, and are listed with their 

 types on a later page. 



The genera described in volumes 9-18 of the "Sylloge" have been included 

 in the proper family keys. Genera placed under "incertae sedis" are excluded 

 as a rule, since it is impossible to locate them definitely. A few genera occur 

 more than once when they show the characters of two families, or when super- 

 ficial and developmental features indicate different positions. An endeavor has 

 been made to make the keys as consistent as possible, and as simple as is profit- 

 able. The mycologist must have a fair equipment of technical terms, as well 

 as a Latin vocabulary, and the sooner these are acquired the better. In many 

 cases, definiteness will seem to be lost by the use of such terms as "typically," 

 "usually," etc., but the beginner must quickly learn that the line between families 

 is rarely clear-cut, but often on the contrary most devious. The tyro must con- 

 stantly be warned that some species belong as naturally in one family as in an- 

 other, and must consequently be sought in more than one place. The color of a 

 spore, the position of a perithecium, or the texture of a cup does not always 



