308 MTBRID8 AND MONGRELS COMPARED. 



one variety is crossed with another variety. For instance, 

 I think those authors are right who maintain that the ass 

 has a prepotent power over the horse, so that both the 

 mule and the hinny resemble more closely the ass than the 

 horse; but that the prepotency runs more strongly in the 

 male than in the female ass, so that the mule, which is an 

 offspring of the male ass and mare, is more like an ass than 

 is the hinny, which is the offspring of the female ass and 

 stallion. 



Much stress has been laid by some authors on the sup- 

 posed fact, that it is only with mongrels that the offspring 

 are not intermediate in character, but closely resemble one 

 of their parents; but this does sometimes occur with 

 hybrids, yet I grant much less frequently than with mon- 

 grels. Looking to the cases which I have collected of 

 cross-bred animals closely resembling one parent, the re- 

 semblances seem chiefly confined to characters almost mon- 

 strous in their nature, and which have suddenly appeared 

 — such as albinism, melanism, deficiency of tail or horns, 

 or additional fingers and toes; and do not relate to char- 

 acters which have been slowly acquired through selection. 

 A tendency to sudden reversions to the perfect character 

 of either parent would, also, be much more likely to occur 

 with mongrels, which are descended from varieties often 

 suddenly produced and semi-monstrous in character, than 

 with hybrids, which are descended from species slowly and 

 naturally produced. On the whole, I entirely agree with 

 Dr. Prosper Lucas, who, after arranging an enormous 

 body of facts with respect to animals, comes to the con- 

 clusion that the laws of resemblance of the child to its 

 parents are the same, whether the two parents differ little 

 or much from each other, namely, in the union of individ- 

 uals of the same variety, or of different varieties, or of 

 distinct species. 



Independently of the question of fertility and sterility, 

 in all other respects there seems to be a general and close 

 similarity in the offspring of crossed species, and of crossed 

 varieties. If we look at species as having been specially 

 created, and at varieties as having been produced by sec- 

 ondary laws, this similarity would be an astonishing fact. 

 But it harmonizes perfectly with the view that there is no 

 essential distinction between species and varieties. 



