Fl 



ora ot Illinois 



Introduction 



The followmg synopsis of the flora of Ilhnois is based on field and 

 herbarium studies carried on during the past five years. The principal objec- 

 tives in its preparation have been to furnish a concise account of the vascular 

 plants of Illinois, and to provide a convenient means of identifying them. No 

 comprehensive treatment of the botany of this state has hitherto been pub- 

 lished, and it is hoped that the present study may serve to stimulate further 

 interest in the local flora. 



This study is based mainly upon material contained in the Herbarium of 

 the University of Illinois, which consists of nearly 300,000 specimens from 

 various parts of the earth, of which approximately one-fourth were collected 

 in Illinois. These comprise all or part of the collections of many Illinois 

 botanists, including M. S. Bebb, F. Brendel, Agnes Chase, V. H. Chase, H. 

 A. Gkason, E Hall, E. J. Hill, F. E. McDonald, W. S. Moffat, H. N. 

 Patterson, R. Ridgway, J. Schneck, and others. The writer's collections of the 

 vascular plants of Illinois consist of approximately 15.0C0 shirts. In addi- 

 tion, the herbaria of the Field Museum of Natural History, and the Missouri 

 Botanical Garden, have been consulted. Mr. V. H. Chase of Peoria has gener- 

 ously placed at the writer's disposal his rich personal collection and that of 

 the Peoria Academy of Science. Dr. G. D. Fuller, Professor of Botany, Emer- 

 itus, at the University of Chicago, and Curator of the Herbarium of the 

 State Museum at Springfield, has contributed a number of specimens and has 

 given valued help in other ways. Other specimens have been donated by 

 several former students, including Mr. Robert Evers of Quincy, and Mr. 

 Richard Schneider of Kankakee. 



During the preparation of these keys numerous sources of information 

 have been drawn upon. The standard botanical manuals,* and monographs, 

 have been of course a constant guide. Special mention should be made of 

 Deam's excellent Flora of Indiana (1940). Parts of the keys to the families 



* Including: Robinson & Fernald, Cray's New Manual of BolanXi (ed. 7) 1908; 

 Britten, Manual of the Flora of the Northern States and Canada (ed. 3) 1907; Britten 

 & Brewn. Illustrated Flora of the Northern States (ed. 2) 1913; Rydberg, Flora of 

 the Prairies and Plains, 1932; Bailey. Manual of Cultivated Plants, 1924; Small, 

 Manual of the Southeastern Flora, 1933; Hitchcock, Manual of the Grasses of the 

 United States, 1935; Rehder, Manual of Cultivated Trees and Shrubs (ed. 2) 1940. 

 The following publications of the Illinois Natural History Survey are useful: Illinois 

 Wild Flowers, by W. B. McDougall; Trees of Illinois, by R. B. Mille. & L. R. 

 Tehon ; and Shrubs of Illinois, by L. R. Tehon. Other works containing data of value 

 te the student of the flora of Illinois are: Pepoon, H. S., Annotated Flora of the 

 Chicago Area; Palmer, E. J., & Steyermark, J. A., Annotated Catalogue of the 

 Flowering Plants of Missouri, and Steyermark, J. A., Spring Flora of Missouri; Fassett, 

 N. C, Spring Flora of IVisconsin ; and Peattie, D. C, Flora of the Indiana Dunes. 



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