Appendix 203 



two periods in the life of Mambrino Chief has 

 been ascribed to the "climatic out-cross." His 

 earlier life was spent in the north where Ham- 

 bletonian was, and his later life was spent in the 

 south. In other similar cases the "climatic out- 

 cross" worked in the opposite direction, — early 

 failure in the south and later success in the 

 north. 



Of the horses born before 1850, none ap- 

 proaches Mambrino Chief in importance as the 

 head of female branches. Either directly through 

 his daughters, or mediately through his sons' 

 daughters, he appears one or more times in nearly 

 all of the 2 : 10 pedigrees. Next in importance 

 stand Pilot Jr. and American Star. All other 

 horses are of minor importance in comparison 

 with these. The ages of the sires and dams of 

 these horses are as follows : 



Born Age of Sire Age of Dam 



Hambletonian 1 849 26 16 



Mambrino Chief, . . . 1 844 23 17 



Pilot Jr 1844 18 12 



American Star 1837 15 (?) 



As these horses appear frequently in the 

 second, third, and fourth generations back from 

 our 2 : 10 trotters, it is not difficult to see what 

 it is that causes the high average age of the 

 third, fourth, and fifth generations. As the breed- 

 ers have been selecting continuously those 



