278 HYBKIDISM. Chap. VIII. 



cation by the selection of mere external differences, and 

 not of differences in the reproductive system. In all 

 other respects, excluding fertility, there is a close gene- 

 ral resemblance between hybrids and mongrels. Finally, 

 then, the facts briefly given in this chapter do not seem 

 to me opposed to, but even rather to support the view, 

 that there is no fundamental distinction between species 

 and varieties. 



