32 CONTACTS WITH DARWINISM II [ch. iii 



a larger area than the genus, the genus than the species, the 

 family must be the oldest, or (where, as is often the case, one 

 genus covers the family area) as old as its oldest genus. This turns 

 the Darwinian theory upside dowTi, for upon it the family is a 

 later appearance. There is, however, no evidence for this. How- 

 ever far back we go in the geological record, we always find 

 families that are identical with some of those of the present day. 

 They are also usually widely separated, so that even at that early 

 period it is clear that if evolution followed the Darwinian plan, it 

 must already have travelled far, though we find no evidence 

 whatever of any intermediate stages upon the way. 



