FOSSIL VERTEBRATES— MAMMALIA 1 87 



Asia during the Pliocene, only left their more northern homes to 

 find a permanent abiding place in Africa at a very late epoch in 



the earth's history." 



E. C. Case. 



References. — Other than the books already referred to, the student will 

 find the most helpful literature in the files and current numbers of The Ameri- 

 can Journal of Science, The American Naturalist, which contains a number 

 of separate articles upon the different groups, by the late Professor Cope, 

 the Proceeding's of the Philadelphia Academy of Science, the Proceedi7igs of 

 the American Philosophical Society, The American Geologist, and. The Kansas 

 University Quarterly. 



