108 University of California. [Vdi.. 2. 



gradual process of evolution within the limits of the middle Tertiary. 

 Immigration and emigration must have been important factors in 

 the change. Granting even that the greater part of the change was 

 due to migration rather than evolution, the faunal changes, together 

 with the climatic or topographic changes which they must neces- 

 sarily have accompanied, are such as usually mark the boundaries 

 between geological periods. 



The evidence at our command indicates that the Sooke beds 

 are of middle Neocene age, and that the time of their deposition 

 was considerably later than that of the Carmanah Point beds. 



University of California, Dec. /, rScj6. 



