American Permian Vertebrates 



By SAMUEL W. WILLISTON 



Late Professor of Paleontology in the University of Chicago 



HIS work comprises a series of monographic studies, with briefer 

 notes and descriptions of new or little-known amphibians and 

 reptiles from the Permian deposits of Texas and New Mexico. 

 The material upon which these studies are based was for the 

 most part collected during recent years by field parties from the University 

 of Chicago. The book is offered as a contribution to knowledge on the 

 subject of ancient reptiles and amphibians, with such summaries and 

 definitions based chiefly on American forms as our present knowledge per- 

 mits. The work is illustrated by the author. 



vi-\-i46 pages and j8 plates, Svo, doth; $2.jo, postpaid $2.62 



THE UNIVERSITY OF CHICAGO PRESS 



CHICAGO ..... ILLINOIS 



The Geography of Illinois 



By DOUGLAS C. RIDGLEY 



The author's aim is to provide an authoritative study of the state, presenting in 

 compact form the wide range of physical influences which make up the geographic 

 environment in which men live. 



The natural features and natural resources of the state are treated in some detail. 

 The great occupations of mankind — agriculture, mining, manufacturing, trans- 

 portation, and trade — are discussed with sufficient fulness to give an adequate 

 idea of their development and present importance within the state. The popula- 

 tion census of 1920 for Illinois is treated in a final chapter. The book is designed 

 to be of interest to the busy citizen who wishes to know his state as a unit in its 

 present-day activities; to teachers and pupils who would know Illinois well enough 

 to interpret other regions in comparison with the home state; to all who wish to 

 learn the reasons for the high rank of Illinois in many lines of human endeavor. 



Abounds with drawings, maps, iUustratiofts, and colored insert maps 

 385 pages, clolh, $2.50, postpaid $2.60 



THE UNIVERSITY OF CHICAGO PRESS 



CHICAGO ILLINOIS 



