PRINCIPLES OF POULTRY BREEDING 79 



the males and females of that cross are bred together, some 

 of the second generation will resemble the other parent, and 

 when these are bred together they will breed true, the off- 

 spring will all resemble their parents. This was shown at 

 the Oregon Station in breeding Barred Plymouth Rock and 

 White Leghorn fowls. The first generation were all white, or 

 practically so, taking after one parent. When these crosses 

 were bred together there was reversion to the Barred parent, 

 some of them being barred, and in mating these barred 

 crosses together they bred true and produced only barred 

 offspring. Again, in crossing a White Wyandotte with a 



BARRED ROCK AND WHITE LEGHORN, FIRST CROSS 



Flock showing dominant color white. 



Single Comb White Leghorn, the offspring had practically 

 all rose combs. Breeding the crosses together, tha off- 

 spring reverted to the Leghorn, some of them showing single 

 combs. Breeding this single-comb offspring together, they 

 bred true to the character single comb. Rose comb is a 

 dominant characteristic, single recessive, and recessives 

 breed true, while the dominants do not. Thte is Mendelism. 

 A knowledge of these facts will often prove useful to the 

 poultry breeder. 



Disadvantages of Crossing. In the foregoing the ad- 

 vantages of crossing have been enumerated. If the dis- 

 cussion were to stop here it might be inferred that the poul- 



