74 Dynamic Evolution 



his progeny was less than one-eighth of that 

 of his grandsire. Similar cases might be mul- 

 tiplied indefinitely. These cases are given 

 simply for the purpose of illustrating the 

 extreme instability of the "blood" of any 

 particular trotting family as compared to 

 the stability of the blood of other kinds of 

 stock. With Holstein-Friesian cattle, the 

 blood of one cow has been predominant since 

 the first importation many years ago. 



A horse cannot be in two places at the same 

 time. A stallion on the race track is not in 

 the breeding establishment, and a stallion in 

 a breeding establishment is not on the race 

 track. It is rare that a stallion gets foals in 

 the same year as that in which he is raced. 



During the period involved in our investi- 

 gation, only a small portion of the stallions 

 used for breeding purposes were ever cam- 

 paigned on the race track. The great major- 

 ity were neither raced nor trained to race. 

 Perhaps half of them never wore harness. 

 Of those broken to harness, a large propor- 

 tion were never driven more than enough to 



