No. 527] 



NOTES AND LITERATURE 



101 



we have no intermediate stages. Hut the discovery of less pro- 

 gressive and specialized descendants of Paleocene Holarctic ani- 

 mals in the African Oligocene would lend support to this con- 

 jecture. Unfortunately. MrtnUhhotrs is referable to a group of 

 disputed affinities in which the dentition is a treacherous and un- 

 certain guide, the reviewer feels obliged to accept the reference 

 with reserve; but it is well to point out its significance if con- 

 firmed. 



The rodent genera described by Osborn are regarded by 

 Schlosser as obviously related to Theridomys and Trechomys 

 of the European Eocene and Oligocene, the relationship being 

 confirmed by the discovery of an upper jaw. (Osborn compared 

 the originals with specimens of these and other European genera, 

 mostly identified by Dr. Schlosser. expecting to find the affinities 

 close; but the most that the evidence warrants is that they prob- 

 ably belong to the same family. There are genera of several 

 other families of rodents which approach the Theridomyid pat- 

 tern and dentition as closely as do Phiomys and Metaphiomys of 

 the Fayum.) 



The foregoing review may appear perhaps unduly critical, 

 uncritical acceptance of the views and conclusions set forth in 



the permanence of scientific theory. And from Dr. S 

 who is justly regarded as one of the greatest living an 

 upon Tertiary mammals, we may fairly demand an ext 

 degree of conservatism. W. D. Mat 



Ameeican Museum of Natural History. 



