UNIVERSITY OF CALIFORNIA PUBLICATIONS 



BULLETIN OF THE DEPARTMENT OF 



GEOLOGICAL SCIENCES 



Vol. 13, No. 8, pp. 31 1-317, 5 figures in text May 1 1, 1922 



A MARSUPIAL FROM THE JOHN DAY 

 OLIGOCENE OF LOGAN BUTTE, 

 EASTERN OREGON 



BY 



CHESTEE STOCK and EUSTACE L. FURLONG 



CONTENTS 



PAGE 



Introduction 311 



Occurrence 312 



Peratherium merriami, n. sp 312 



Type specimen 312 



Specific characters 312 



Description 313 



Summary _ 317 



INTRODUCTION 



During the summer of 1920 a field party from the Department of 

 Palaeontology, University of California, visited the region of Logan 

 Butte, south of the Crooked River in eastern Oregon, and collected in 

 the John Day Oligocene deposits. Among the specimens obtained is a 

 small, fragmentary skull apparently belonging to the genus Pera- 

 therium. An important member is thus added to the large and varied 

 mammalian assemblage known from the John Day beds. The presence 

 of Peratherium at Logan Butte records for the first time a marsupial 

 in Tertiary deposits of the Great Basin Province and presumably rep- 

 resents the latest occurrence of the genus in North America. 



The writers desire to express their appreciation to Mr. Gerrit S. 

 Miller for helpful suggestions in the study of the John Day species 

 and for the arrangement of a loan of mammal skulls from the U. S. 

 National Museum. Drawings of the John Day material were submitted 

 to Dr. W. K. Gregory of the American Museum of Natural History 

 and to Mr. J. W. Gidley of the U. S. National Museum. Dr. Gregory 

 and Mr. Walter Granger made comparisons with specimens in the 

 American Museum and directed attention to the resemblance between 



