PREFACE 



In the over fifteen years that have elapsed since the pubhcation of the 

 author's "A Text-book of Mycology,"^ the subject has experienced many 

 changes. The subject of Medical Mycology has gained greatly in interest 

 and there has arisen a great realization of the importance of those fungi 

 whose antibiotic products have become indispensable in the treatment 

 of many maladies of Man and other animals. It has therefore become 

 apparent that an entirely new work is necessary, not merely as a textbook 

 for students but also to assist the many persons now undertaking research 

 in the various fields of study in which the knowledge of fungi is funda- 

 mental to their work. Although in some features the present work follows 

 the framework of the older Text-book it has been entirely rewritten and 

 greatly enlarged. 



Aside from the above-mentioned special fields of study, investigations 

 of the microscopic soil and water fungi, both parasitic and saprophytic, 

 which comprise the simplest forms, in structure at least, have revealed 

 hundreds of species and many new genera, families, and even orders. Thus 

 great numbers of fungi are now known where but few were recognized less 

 than two decades ago. This has compelled radical revisions in the classi- 

 fication of the lower fungi. 



In the higher fungi, especially the Basidiomyceteae, many new species 

 and genera have been described. Above all, studies in the anatomy and 

 chemical reactions of these new as well as of the old, long known species 

 have shown the artificiality of the old Friesian system of classification. 

 This has led to radical revisions which beyond doubt indicate far more 

 correctly the true relationships and phylogeny of the members of this 

 class. Yet here, there still remains so much to be done that mycologists 

 are not at all in agreement as to the ultimate system of classification to 

 be used. 



With so many points still in disagreement, it is impossible for a book 

 of this type to settle these matters beyond dispute. The author, therefore, 

 while taking a middle ground in many disputed areas, has attempted to 

 show those using this book the various points of conflict and opposing 



1 Bessey, Ernst Athearn: A Text-book of Mycology, xv -f- 495 pp., 139 tigs., 

 Philadelphia, Blakiston, 1935. 



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