PRINCIPLES OF POULTRY BREEDING 63 



same size when hatched, but from, that time on the influence 

 of heredity will be shown in the larger growth of the chick 

 that has an ancestry showing large size. When a pure-bred 

 Leghorn is mated to a pure-bred Leghorn it is almost a cer- 

 tainty that the offspring will be fowls of small size. 



When the male offspring begins to crow, it does so be- 

 cause of this same law ; its male ancestors for thousands of 

 years have crowed. Sometimes the breeder, and often the 

 nearby neighbor in the early hours of the morning would 

 prefer that this law was more flexible and that it were pos- 

 sible to breed chickens without a crow, but the breeder 

 knows by experience that there are certain characteristics 

 that have become fixed and that if he attempted to change 

 them he would get nothing for his pains. So is egg-laying 

 a fixed characteristic. It is a law of nature or heredity that 

 the hen lays eggs. The law is that like begets like. The 

 practical breeder is guided by this law first and foremost. 



But while the law of heredity is persistent and inflexible, 

 while like begets like, there is the strange contradiction in 

 nature that no two individuals are alike. The male chickens 

 all crow; they are alike in that respect, but there are dif- 

 ferences in the crow which are easily discernible. So the 

 females are alike in regard to laying eggs ; they all lay eggs, 

 but there are differences in the layers; some will lay five 

 eggs a week, others one ; some 200 a year, others 20. Another 

 law is seen here. 



Variation. It is the law of variation. This law of varia- 

 tion has already been referred to. Some fowls of the same 

 ancestry or breed vary in number of points in the comb, in 

 size of comb, in length of wattles, in color of eye, in length 

 of limb, in color of plumage, in amount of meat, in size or 

 weight of bone, in number of eggs laid, in size and color of 

 egg, etc. This is variation. Variation is the opportunity 

 for the breeder. The problem that confronts him at the out- 



