158 THE BREEDING OF ANIMALS 



resulting from use and disuse and the effects of environ- 

 ment were transmitted by heredity. 1 



Among those who have failed to find satisfactory 

 evidence of the inheritance of modifications must be 

 mentioned Kant, Blumenbach, and later Gal ton, Weis- 

 mann, Ray Lankester and practically all the leading 

 biologists of modern times. 



148. Practical breeders believe in transmission of 

 acquired characters. There is a widespread belief 

 among the breeders of domestic animals that acquired 

 characters are inherited. To the practical breeder of 

 dogs who has observed the sensitive reaction of the fox 

 hound to the scent of the fox, or the alertness of the setter 

 or pointer in the presence of a fresh bird track, it is diffi- 

 cult to find a satisfactory explanation for existing facts 

 without assuming that the results of the training of a 

 dog to some extent must be transmitted. Extreme speed 

 in running and trotting horses is the result of training 

 and exercise. The offspring of parents who have acquired 

 extreme speed through training and exercise are more apt 

 to possess the ability to acquire similar extreme speed 

 than the offspring of parents who have not been trained. 

 The practical breeder concludes, therefore, that the ac- 

 quired speed must be transmitted. 



There are many breeders of beef cattle who firmly 

 believe that by maintaining the breeding animals in high 

 condition, the calves will have a more pronounced devel- 

 opment of those characters which are recognized as 

 belonging to the beef type than will the calves of parents 

 which are maintained on a low plane of nutrition. 



The breeder is an accurate observer, and there can be 

 no question that his facts are generally correct in this 

 1 Thomson, " Heredity," p. 170. 



