No. 523] SHORTER ARTICLES AND CORRESPONDENCE^ 



is used in contrast with conditions in average horses and the 

 actual figures for the ages of progenitors of average horses are 

 not given to us. hut assumed to he much lower. This assumption 



It would he very interesting to have the average ages of 

 grandsires. givat-grandsires. etc.. of the first thousand horses 

 named in the "Index Digest" and used by Mr. Redfield to 

 represent average horses. 



I have considered it fairer, however, to use a group, though 

 smaller, more nearly contemporaneous with the 242 horses of 

 2.10 records used in my previous study. It would be desirable 

 to have a figure based upon the study of the 2.10 list as it stood 

 at the end of 1 !><>!). hut a comparison of the two groups here used 

 is, I think, a fair one. The group used to represent average 

 horses and as having been bred at about the same time as the 

 242 1 horses with 2.10 records consists of the first 242 horses 

 registered in Volume 15 of the "Register." 



The following tabulation will show that the two groups were 

 contemporaneous : 



I am still of the opinion that an impartial study of the figures 

 does not show that age is, of itself, any factor in the inheritance 



