384: PRINCIPLES OF STOCK-BREEDING. 



ter may obscure the relations existing between it and 

 the organs with which it is correlated. 



A single illustration will be sufficient to explain 

 the apparent exceptions to the law of correlated struct- 

 ure and function that are frequently observed. A 

 trotting horse, for example, with an extraordinary 

 development of vital power, may be remarkable for 

 its speed, notwithstanding a disproportion in its or- 

 gans of locomotion, the defect in its structure being 

 overcome by an excess of power. If, on the other 

 hand, its limbs have the best possible proportions for 

 rapid trotting, and its vital or nervous energy is defi- 

 cient, it may fail in its performance, notwithstanding 

 the perfection of its external conformation. 



It does not follow from cases like these that the 

 proportions of the limbs are a matter of indifference 

 in the development of a high rate of speed, as better 

 results would undoubtedly have been obtained in both 

 cases if the defect had not been present. 



