CROSS-BREEDING. 205 



characters that constituted their distinguishing char- 

 acteristics. 



The greater the contrast presented in the two 

 breeds, and the greater the specialization of their quali- 

 ties through the development of artificial characters, 

 the stronger the tendency to obscure the best charac- 

 ters of each, and restore the original type from which 

 they had been developed. 



In such cases the offspring would in all probability 

 prove to be inferior in quality, from the inheritance 

 of the defects of both parents, without retaining the 

 most desirable characters of either. 



All the best authorities on cross-breeding agree 

 that it should not be practised without a definite ob- 

 ject, on account of this tendency to the development 

 of undesirable variations. 



Mr. Dickson says : " I object to promiscuous cross- 

 ing as much as any man. It is to this injudicious sys- 

 tem that may be traced the existence of so many mis- 

 erable breeds of cattle in the country." 1 



""We may start, then," says Mr. Spooner, "with 

 this principle, that to cross for crossing sake is decided- 

 ly wrong / that, unless some specific purpose is sought 

 for by crossing, it is far better to cultivate a pure 

 breed." a 



Prof. Tanner remarks that, " in the case of pure- 

 bred animals, there should be no opposing influence 

 to weaken the hereditary tendencies of the offspring, 

 but on the other hand a concurrent and sympathetic 

 nature, so that the hereditary character may be con- 



1 Quarterly Journal of Agriculture, vol. vii., p. 508. 



2 Journal of the Royal Agricultural Society, vol. xx., p. 298. 



