FOREWORD 



IN 1936 the first number of the Manual series of the Natural His- 

 tory Survey Division appeared. It was titled the Firldbook of 

 Illinois Wild Flowers. This was followed in 1939 by the Fieldhook 

 of Illinois Land Snails, and in 1942 by the Fieldhook of Native 

 Illinois Shrubs. These were developed under the charge in the 

 Illinois statute which directs the Board of Natural Resources and 

 Conservation, under which this Survey operates, "To publish, from 

 time to time, reports covering the entire held of zoology and botany 

 of the State." 



That these manuals have served a useful purpose is obvious in 

 the constant demand for them. The Fieldhook of Illinois Wild 

 Flowers has long been out of print, and a revised edition is now in 

 preparation. 



Now appears the fourth in this popular and useful series, the 

 Fieldhook of Illinois Mammals. This work was inaugurated by 

 Dr. Carl O. Mohr of the Natural History Survey staff over a decade 

 ago. Upon his leaving the service of the state it was possible to 

 persuade Dr. Donald F. Hoffmeister, Curator of the Natural His- 

 tory Museum of the University of Illinois and an eminent mammal- 

 ogist, to continue this project. Dr. Mohr has recently returned to 

 Illinois and has collaborated in the final stages of the project. 



It is difficult for one or even two people to develop to completion 

 a project such as this. We are greatly indebted to Mrs. Leonora 

 K. Gloyd and Dr. Philip W. Smith of the Natural History Survey 

 staff for the great amount of painstaking work which they expended 

 on various duties related to the development of the manuscript. It 

 would have been most difficult to complete the project without their 

 unselfish assistance. 



Further appreciation should be given to the Survey's Technical 

 Editor, James S. Avars, who has carried on his responsibilities with 

 characteristic vigor and sensibility, to Dr. H. H. Ross, Head of 

 the Section of Faunistic Surveys and Insect Identification of this 

 Survey, who directed the many activities prior to the editing of the 

 manuscript and who was responsible for continued activity over 

 the past decade, and to Mrs. Blanche P. Young, Assistant Technical 

 Editor, for assistance with many editorial problems. 



It is hoped that this manual will be found as helpful in educa- 

 tional circles and among interested laymen as the three volumes 

 which preceded it. 



H milow B. Mn is, Chief 

 i'rhana, Illinois 

 February S, 1957 



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