4 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 480 



Importance of the Illinois Basin to Paleobotany 



Studies of Pennsylvanian plants of the Illinois Basin have had a major im- 

 pact on American paleobotany. Twenty- five compression- impression floras, 14 

 coal-ball horizons, and at least 75 coals have been identified in the basin. The 

 numerous publications on the Mazon Creek flora from northeastern Illinois have 

 made it one of the best known Pennsylvanian floras in the world. 



The early biologically oriented studies of fossil plants in the Illinois Ba- 

 sin — the investigation of plant evolution and ontogeny from coal balls — have pro- 

 vided much complementary data on the anatomy of coal swamp plants in the mid- 

 dle and upper parts of the Pennsylvanian, have stimulated similar studies in Iowa 

 and Kansas, and have provided training for many paleobotanists. Some of the 

 earliest studies in palynology in the United States were carried out in the Illinois 

 Basin, and important contributions to the taxonomy of fossil spores and the paly- 

 nological correlations of coals have been based on Illinois Basin floras. 



General Reports on the Paleobotany of the Illinois Basin 



The history of paleobotany in the Illinois Basin is a regional story, but it 

 is intricately related to the widespread growth of American paleobotany. Contem- 

 porary botanists who first established paleobotany programs in a number of univer- 

 sities have prepared accounts of the several facets of paleobotany in the Illinois 

 Basin. The History of Paleobotany in Indiana by Canright (1958) deals largely 

 with the development of studies of compression-impression floras in Indiana, while 

 Darrah's (1969) A Critical Review of the Upper Pennsylvanian Floras of Eastern 

 United States with Notes on the Mazon Creek Flora of Illinois gives considerable 

 background on the collection and study of that famous flora. 



Broad treatments of coal-ball studies are to be found in Andrews (1951) and 

 Darrah (1941b). Summaries and citations of palynological studies in the Illinois 

 Basin were given by Kosanke's (1950) Pennsylvanian Spores and Their Use in Cor- 

 relation and Winslow's (1959) Upper Mississippian and Pennsylvanian Megaspores 

 and Other Plant Miorofossils from Illinois, 



A summary of the early geological studies in Illinois up to 1930 and the 

 founding and history of the present Illinois State Geological Survey were presented 

 by Rolfe (1931) and former directors of the Survey (Bain, 1931; DeWolf, 1931; Leigh- 

 ton, 1931) at that organization's Quarter Centennial Celebration in 1930. 



The most complete bibliographies on the Illinois Basin, including many 

 paleobotanical studies of the area, are the Bibliography and Index of Illinois 

 Geology Through 1965, prepared by Willman et al. (1968), and the Annotated Bibli- 

 ography of Indiana Geology Through 1955, compiled by Never s and Walker (19 62). 



Our purposes in preparing this account of the development of paleobotany 

 in the Illinois Basin are to introduce geologists, botanists, and others to all the 

 branches of paleobotany, to illuminate the personal side of past research and the 

 cooperation that has existed among researchers, to suggest some areas for future 

 research, and to provide a guide for teachers and students of paleobotany. 



SCHOOLCRAFT TO FOERSTE— A CENTURY 



H. R. Schoolcraft 



Probably the first reports on a fossil plant in Illinois were made by H. R. 

 Schoolcraft (1822a, 1825). On one of his expeditions into the newly opened 



