PAPERS ON BIOLOGY AND AGRICULTURE 193 



Weaver, J. E. and Theil, A. F. 



Ecological Studies in the Tension Zone Between Prairie and 

 Woodland. 



Univ. Neb. Bot. Surv., 1:1-60, 1917. 



ACKNOWLEDGiMENTS 



Thanks are especially due to Mrs. R. H. Kauffman of Oregon. Ogle 

 County, for her public-spirited kindness in furnishing a great deal of data in 

 addition to that in her history of the county, and to Mr. Charles D. Etnyre, 

 also of Oregon, for his assistance in furnishing information for the writer in 

 the field, and to Mr. F. G. Taylor, of Oregon, the Superintendent of Schools, for 

 his kind assistance in the field. 



Mr. C. J. Root. Chief of the State Weather Bureau, U. S. Department of 

 Agriculture, at Springfield, Illinois, has kindly supplied data and information 

 relating to the northern part of the state. 



The State Soil Survey, Urbana. Illinois, has also kindly supplied infor- 

 mation relating to the unpublished soil survey of Ogle County. 



Thanks are due to Dr. Henry C. Cowles and Dr. George D. Fuller of the 

 University of Chicago, Department of Botany, for their assistance and advice. 



