been impossible to obtain the means of publication until the 

 Carnegie Institution offered to provide the funds for printing the 

 volume of which the first part is now ready. 



The Index, it should be borne in mind, does not purport to be 

 a summary of all references to North American fungi, but is 

 limited to those which concern the systematic mycologist, and does 

 not include- references to papers on fungicides and other tech- 

 nical and agricultural subjects as such, but cites them only when they 

 also contain notes of interest to the systematist. The literature of 

 these branches of applied mycology is already sufficiently fully given 

 in different government publications and technical journals. Nor 

 have we included, in general, references to works treating specially of 

 the physiology of fungi, for the reason that physiological questions 

 are from their nature general and not local. The physiology of 

 North American fungi is not different from that of fungi of other 

 parts of the world, whereas the study of our species from a system- 

 atic point of view has a definite local as well as a general impor- 

 tance. What is true of physiological writings is to a great extent 

 true of cytological writings, but we have introduced references to 

 important cytological works published in this country based on 

 material collected here since they have a bearing on morphology 

 and classification. Bacteria and Saccharomycetes are excluded, 

 as those groups at the present day are studied by specialists and not 

 by those interested in what are commonly known as fungi proper. 



With these exceptions the Index includes all the references to 

 species of North American fungi known to us, but it should be 

 remarked that in the case of a few species, as Agaricus campestris, 

 which are very common and which from their popular interest have 

 appeared over and over again in journals of every description, we 

 have omitted many references and given only those which are of 

 importance as showing their range or as furnishing good illustrations. 

 As it is, we may perhaps be considered to have been over liberal. 

 It should also be remarked that we have cited only references to 

 North American species as they occur in North America and have 

 not given references to North American species as they occur in 

 Europe. A few perplexing cases have arisen in which new species 

 have been described in Europe parasitic on plants recently im- 

 ported from America. The supposition is in such cases that the 

 fungi themselves were imported from America and we have accord- 



