HEREDITY AS A FORCE. 17 



take the instance of the range-bred polo pony as 

 proving the converse of this proposition. Com- 

 mon range mares are mated witli Thoroughbred 

 stallions and the foals are suitably environed. 

 In this way we breed the best polo ponies on 

 earth. Allowed to run on the range with their 

 mothers these foals, not subject to the environ- 

 ment which makes polo ponies, develop into 

 common rangers. 



Approaching the problem of what heredity 

 will do for us, parents will transmit a measure 

 of their joint individuality to their offspring. 

 Thus if we mate a stallion and a mare both pro- 

 nouncedly droojDing in the rump, the foal will 

 almost to a surety exhibit that faulty conforma- 

 tion. Hence it follows that when either parent 

 has some undesirable characteristic great care 

 should be exercised to select the other very 

 strong in that particular point. These undesir- 

 able factors in conformation seem to be trans- 

 mitted with greater force and certainty than 

 those which we most desire. If we use stallions 

 and mares of low grade we are merely inviting 

 the production of doubly inferior progeny. 

 Heredity is not altogether impartial in this mat- 

 ter. The best stallion will only beget a certain 

 proportion of his offspring good. The inferior 

 stallion will beget progeny, a large majority of 

 which will be bad — this of cours2 presupposing 

 that the mares will average with the horse. If 



