RELATIONSHIP OF SPECIES. 453 



differs from the Lion of the Cape, but it is equally interesting, 

 if not more so, to know whether the Tiger is more closely 

 connected to the Lion or to the Leopard, and if anyone can give 

 me any definite information on this point I shall feel very 

 grateful to him. 



If, however, those writers are correct who hold that the 

 results of hybridization are only governed by chance, most of 

 the above remarks will be evidently of no value. In spite of the 

 very curious results arrived at in the cross-breeding of plants, 

 and which, I believe, give rise to this theory of chance re- 

 semblance, I have always felt far from convinced that this view 

 is the correct one. 



It will be observed above that I have spoken about the 

 various results of hybridization (as to whether the young is 

 fertile or not) as being "what we might expect." These expecta- 

 tions I have based not on the text-book classification, but (when- 

 ever possible) on observations of certain characteristic actions of 

 the animals, and as to whether they were congeneric or aberrant. 



I have rarely seen in any of the general results of hybridiza- 

 tion (in animals at least) anything that appeared particularly 

 extraordinary in these results ; allowing that these may seem 

 extraordinary to the systematist, they appear, if one bases 

 classification on a comparison of habits, to be eminently in 

 agreement with these latter. It is rarely we get any informa- 

 tion on these points. In an article that I read on this subject 

 some years ago, entitled " Can Mules Breed ? " * I noticed 

 that the writer (F. Finn), amongst other things, stated : 

 "Amongst beasts the American Bison produces a hybrid with 

 the common Cow, and this hybrid is fertile ; no one will pretend 

 that these two creatures are not as distinct as the Horse and 



Ass, if not much more so In the Zoo can be seen at 



present a hybrid between a Polar Bear and a Brown Bear, and 

 a three-quarters bred animal from this beast mated to a pure 

 Polar Bear. These Bear mules have also bred between them- 

 selves, and the two parent species again are more different than 

 Horses and Asses are." 



I believe the view above expressed is the one very generally 



* ' The Feathered World.' 



