PREFACE TO THE FIRST EDITION ix 



A few specimens are cited; the following abbreviations denote the 

 location of the material : 



B.M. British Museum (N.H.), London 



F. Farlow Herbarium, Harvard University 



L. Herbarium of D. H. Linder, Harvard University 



S. Sparrow collection. 



It is probable that no book of this nature ever appears without the 

 friendly support and active cooperation of various persons and insti- 

 tutions. Particularly is this true of the present work in all its phases. 



The preparation of the manuscript was immeasurably facilitated by 

 grants from the Faculty Research Fund and the Horace H. Rackham 

 Fund. Its publication was made possible by appropriations by the 

 Board of Regents of the University of Michigan. 



The laborious task of preparing reproductions of illustrations from 

 other authors has for the most part been done by Richard Higgins 

 and Frances Gracey. Permission to use these illustrations has been 

 generously given wherever the authors could be reached; the sources 

 have been acknowledged in each instance. Professor H. Munro Fox, 

 editor of Biological Reviews, has kindly allowed the reproduction of 

 Figure 1, 1 which is taken from that journal. James McCranie has 

 generously contributed certain figures on the cytology of Allomyces, 

 and V. M. Cutter, Jr., that of Rozella allomyeis. If no acknowledgment 

 is made, the illustration is an original one prepared for this book. 

 I am indebted to Professor Sarah Bach-Wiig, of Smith College, for 

 the portrait of Dangeard, to the botany department of Michigan State 

 College for that of Zopf, and to Doctor O. Gram, of Copenhagen, 

 for that of Petersen. 2 



To Miss Grace Potter, assistant editor of scholarly publications of 

 the University of Michigan, I should like to express my very great 

 appreciation for her painstaking editing and careful supervision of 

 the manuscript while in the process of publication. To Nan Gabler 

 Sparrow, I am greatly indebted for help in reading proof and for her 

 ready and able assistance in the preparing of this and other manuscripts 

 for publication. 



1 Figure 3 in this edition. 2 Omitted in this edition. 



