MEMOIRS OF THE PEABODY MUSEUM OF YALE UNIVERSITY 



VOLUME III • PART I 



AMERICAN 

 MESOZOIC MAMMALIA 



BY 

 GEORGE GAYLORD SIMPSON 



ASSOCIATE CURATOR OF VERTEBRATE PALEONTOLOGY IN 

 THE AMERICAN MUSEUM OF NATURAL HISTORY 



NEW HAVEN • YALE UNIVERSITY PRESS 



LONDON • HUMPHREY MILFORD • OXFORD UNIVERSITY PRESS 



1929 



