68 Dynamic Evolution 



trotting work some of these road mares did 

 before being bred is quite surprising. Being 

 driven from twenty to thirty miles per day 

 was not unusual, and there are cases known 

 of such mares being required to travel more 

 than one hundred miles in one day. A mare 

 which does this kind of work for ten or 

 twelve years may be considered as well 

 developed from the dynamic standpoint. 



What ones of these breeding operations do 

 we find frequently in the grandparents and 

 earlier progenitors of our 2 : 10 trotters, and 

 what ones do we never find there? They 

 represent all kinds of breeding experiments, 

 from the extreme of activity to the extreme 

 of idleness, and extending across a continent 

 and over a century of time. From twenty to 

 fifty years after the breeding of these diverse 

 and intermingled experiments, the descend- 

 ants are submitted to breeders who form 

 their judgments from what is occurring at 

 the time on the race track and who give no 

 consideration to the experiments themselves. 

 The breeders discard what they consider as 



