108 ILLINOIS STATE ACADEMY OF SCIENCE 



LITERATURE CITED 



1. Savage, T. E. 



The Devonian Formations of Illinois. 

 Amer. Jour. Sci. 49:169-182. 1920. 



2. Worthen, A. H. 



The Geology of Alexander County, 

 m. Gaol. Surv. 3:20-32. 1868. 



3. Savage, T. E. 



The Faunal Succession and the Correlations of the Pre-Devonian For- 

 mations of Southern Illinois. 



111. State Geol. Surv. Bull. 16:302-341. 1910. 



4. Hall, R. C. and Ingall, 0. D. 



Forest Conditions in Illinois. 



Bull. 111. State Lab. Nat. Hist. 9:175-253, pis. 21-36. 1911. 



