142 PROCEEDINGS OF THE PALEOXTOLOGICAL SOCIETY 



interpretation of the enlarged rodent-like teeth of Cheiromys (Dauhentonia). 

 The author replied that the lower pair were regarded as canines, the upper 

 pair as incisors: 



RESTORATIOXS OF THE WORLD SERIES OF ELEPHAXTS AXD AIASTODOXS 



BY H. F. OSBOEN 



The author exhibited photographs of a series of models of living and extinct 

 Proboscideans recently executed by Mr. Charles Knight under his direction, 

 and explained the basis of certain new features in the restorations of extinct 

 types. 



The meeting then adjonmed. 



The afternoon session was called to order by Professor Lull at 2.30 

 p. m., and the program of papers continued as follows : 



FAUXA OF THE CUMBERLAXD PLEISTOCEXE CAVE DEPOSIT 

 BY J. W. GIDLEY 



The author described the discovery and situation of this cave and the nature 

 and probable origin of the deposit, and gave a brief resume of the principal 

 types identified in the material secured by his explorations for the National 

 Museum. 



Discussion 



Doctor Matthew commented on the interest of certain African types in this 

 fauna and their possible interpretation as relics of a former Holarctic distri- 

 bution. The author regarded this as the most plausible explanation of their 

 occurrence. Professor Osborn also spoke of the importance of Mr. Gidley's 

 discoveries, and especially of the positive identification of the eland. 



RECTIGRADATIOXS AXD ALL0IMETR0X8 IX RELATIOX TO THE COXCEPTIOX 

 OF THE "MUTATIOXS" OF WAAGEX 



BY H. F. OSBORN 



The author explained the nature of these mutations which are the progres- 

 sive changes in a phylum in passing from one species to another, having the 

 same relation to geologic time that regional varieties have to geographic space. 

 The mutative changes are of two kinds, either the progressive development of 

 new and disappearance of old characters along certain predetermined lines of 

 evolution (rectigradations) or changes in proportion of different parts (alloi- 

 metrons). 



MIOCENE DOLPHIX FROM CALIFORXIA 

 BY BICHABD S. LULL 



The authors exhibited photographs of the fossil skeleton of an extinct ceta- 

 cean recently presented to the Yale Museum. It appeared to be nearly allied to 

 the modern Dolphin, but more primitive in certain features. 



