PREFACE. 



The present book is a corrected and extended edition of 

 The Syllabus of Lectures on Geology and Paleontology ; 

 Part III, Paleontology of the Vertebrata, published July 

 8, 1891. It was originally designed for use in the Exten- 

 sion Lectures of the University of Pennsylvania, and I 

 have used it as a text-book for the undergraduate classes in 

 the School of Biology of the University. The system 

 adopted is, with some minor exceptions, that which was 

 first presented by the author in the American Naturalist of 

 October, 1889. This was based upon original research on 

 the recent and extinct forms, with the exception of the 

 part relating to the Aves. This M'as taken, with little 

 modification, from Stejneger. 



E. D. COPE. 

 University of Pennsylvania, 

 Philadelphia, 1897. 



