CONTRIBUTIONS FROM WALKER MUSEUM. I. 



THE VERTEBRATES FROM THE PERMIAN BONE BED 

 OF VERMILION COUNTY, ILLINOIS. 



The material described and figured in the present contribu- 

 tion comprises a portion of the vertebrate material of the Gurley 

 Collection of Fossils in the Walker Museum, at the University of 

 Chicago. The material is of extreme interest from both an 

 historical and a scientific standpoint, its discovery being the first 

 evidence of the occurrence of Permian reptiles in North America. 

 A few isolated bones were submitted to Professor Cope, and 

 with his usual keen insight he recognized their character and 

 their value, and by his interest he stimulated the work of their 

 careful collection and preservation. To Mr. Gurley is due the 

 credit for a careful and exhaustive exploration of the "bone 

 bed," and the preservation of the material. 



Many of the forms were described by Cope in the files of the 

 Proceedings of the Philadelphia Academy of Natural Science, 

 and the American Philosophical Society, but only a few illustra- 

 tions of the intercentra of Cricotus have ever been published. 

 It was his intention to publish full descriptions of the forms, 

 with illustrations, and for this purpose plates had been prepared 

 for an article in one of the government publications, which was 

 never issued. Much of the material is fragmentary, and nearly 

 all the bones were found isolated, so that it is especially diffi- 

 cult to identify the species from the descriptions alone. Espe- 

 cially is this true when the specimens to be compared come 

 from another locality. 



In the present paper the original descriptions have been 

 reproduced, wherever they would serve the purpose, along with 

 some additional notes, and the specimens figured. In many 

 instances the figures have been copied from those prepared by 

 Cope for his unpublished work. A few of the specimens 



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