VARIATION 205 



after the experiment closed. Had it not been for these 

 two hindrances Rose would doubtless have made even a 

 better record than she did. 



" While there is a vast difference in the profit derived 

 from the two cows in this experiment, the difference is 

 by no means phenomenal, as greater differences than 

 here cited may frequently be found among cows in the 

 same herd, for the cow Nora, the poorer of the two, was 

 in reality an exceptionally good cow, producing 348 Ib. 

 of butter in a year which is nearly three times the average 

 yield (130 Ib.) of cows in the United States and almost 

 one-half more than the average yield (250 Ib.) of profitable 

 cows in Illinois. Had Rose been compared with a really 

 poor cow, such as may be found in nearly all dairy herds, 

 there would have been a much greater difference in profit 

 in favor of Rose ; for she gave nearly five times as much 

 as a profitable cow for Illinois." 



In the cases of variation mentioned, the individuals 

 compared have belonged to different breeds or have been 

 unrelated. It is also true that animals which are from 

 parents of the same blood lines may show wide variations. 

 In the dairy herd belonging to the University of Missouri, 

 there were at one time nineteen daughters of the Jersey 

 bull Minette's Pedro. Many of the mothers of these 

 cows were from another bull and all were of similar breed- 

 ing. The conditions surrounding these cows were alike ; 

 their dams, grand dams, and great grand dams were all 

 similarly bred and every cow of the nineteen was sired 

 by Minette's Pedro. These cows should have exhibited 

 some uniformity in the development of dairy qualities. 

 The table records the annual production of milk and 

 butter, and shows rather wide variations in the productive 

 capacity of the different cows : 



