BREEDING 



115 



the chances of the appearance of the mongrel character- 

 istics in the fifth generation, as shown at "K," would be 3| out 

 of 100, and the chances in the following generation not indi- 

 cated in the chart would be ly^^^ out of 100. In the early 

 history of many of the pure breeds of live stock the sixth and 

 seventh cross, as here shown, were admitted for registry. 



The actual improvement with regard to uniformity runs 

 rather in advance of the percentages shown in the chart 



Fia. 52 



A hen carrying seven-eighths Single Comb White Leghorn blood whose 

 egg record is 303 in twelve months and 505 for twenty-four months. 

 (Courtesy of Oregon Experimemt Station.) 



after the first cross, since the bodily resemblances between 

 the offspring are nearly always closer than the likenesses in 

 hereditary makeup. Furthermore, standard-bred males 

 are prepotent over mongrel females in most characteristics. 

 Prepotency is the breeders term for the superior power 

 which one parent has over the other in determining the char- 

 acter of the offspring. It increases with (1) standard breed- 

 ing, (2) line breeding, and (3) long breeding, because each 



