HEREDITY AS A FORCE. 15 



the characteristics of some ancestor is uncon- 

 querable and this atavism, as it is called, must 

 be reckoned with always as well as variation. 

 These tendencies must of necessity be met with 

 more frequently in improved breeds of recent 

 and composite origin and varying environment 

 than they are in wild animals which have bred 

 without alien blood and without change of sur- 

 roundings for an indefinite period of time. 

 Hence improved animals bred and selected for 

 many years with one fixed object in view must 

 more strongly transmit their characteristics to 

 their offspring than those which have resulted 

 from hap-hazard matings. 



Natural selection is governed by the inexora- 

 ble law of the survival of the fittest. Matings 

 of improved stock are often ordered at random, 

 without due regard to true fitness, and be it 

 said for the great mass of breeders compara- 

 tively seldom with a definite ideal in view. Even 

 the greatest breeders have never collectively 

 directed their efforts along exactly the same 

 line. Therefore we have types and types within 

 the same breed. An inexorable law, always 

 without change, has ordered the selection of 

 parents in the wild races. Crossed this way 

 and that within itself, an improved breed pre- 

 sents sometimes as many types as there are 

 great breeders and the great luajority of the 

 animals within the breed can not be called typ- 

 ical at all — they lack the touch of the master 



