Appendix C. 171 



He also informs me that pure white beasts of either sex 

 are so well known by experienced breeders to be comparatively 

 infertile together, that they are never used for breeding 

 purposes, so that "in some parts of the country, where a 

 tendency to sterility had become so confirmed in the white 

 race that they utterly died out," only the coloured breeds are 

 now to be found. He goes on to say that if " a lot of white 

 heifers were put to a lot of white bulls, I think you would 

 probably get a fertile breed of pure white cattle. ... I think, 

 in short, that domestication has produced just what your 

 theory suggests, a new variety inclined to prove sterile with 

 its parent stock." 



Commenting on the origin of domesticated catde. Professor 

 Oscar Schmidt remarks {Doctrine of Descent, p. 139) — 



" Riitimeyer's minute researches on domestic cattle have shown 

 that, in Europe at least, three well-defined species of the diluvial 

 period have contributed to their formation — Bos primigenius^ 

 longifrons, and frontosus. These species once lived geogra- 

 phically separate, but contemporaneously ; and they and their 

 specific peculiarites have perished, to rise again in our domestic 

 races. These races breed together with unqualified fertility. 

 In the form of skull and horns they recall one or other of the 

 extinct species ; but collectively they constitute a newmain species. 

 That from their various breeds, the three or any one of the 

 aboriginal species would ever emerge in a state of pristine 

 purity, would be an utterly ludicrous assertion." 



Now, seeing that these " aboriginal species," although living 

 "contemporaneously," were "geographically separate," we 

 can well understand that their divergence of type from a 

 common ancestor did not require, as a condition to their 

 divergence, that any cross-sterility should have arisen between 

 them. The geographical isolation was enough to secure 

 immunity from mutual intercrossing, and therefore, as our 

 present theory would have expected as probable, morpho- 

 logical divergence occurred without any corresponding physio- 



