PRINCIPLES OF POULTRY BREEDING 69 



laying qualities to her offspring, even though her offspring 

 come in various colors, sizes and shapes. 



A noted exponent of Mendelism says that purity of type 

 "has nothing to do with a prolonged course of selection, 

 natural or artificial. ' ' Again he says : ' ' An organism may 

 be pure-bred in respect of a given character though its 

 parents were cross-bred in the same respect. Purity depends 

 on the meeting of the two gametes bearing similar factors, 

 and when two similarly constituted gametes do thus meet in 



BREED IMPROVERS 



Pedigreed cockerels, all from stock, with records of over 200 eggs in a year. 

 They were sent to breeders in various sections of the United States and to 

 several foreign countries to breed better layers. Bred at the Oregon Station. 



fertilization the product of their union is pure. The belief, 

 so long prevalent, that purity of type depends essentially 

 on continued selection is thus shown to have no physiological 

 foundation. Similarly, it is evident that an individual may 

 be pure in respect to one character and cross-bred or impure 

 in respect of others." (Bateson) Again, "An animal may 

 have one thirty-secondth of the blood of some progenitor, 

 and yet be pure in one or more of its traits. ' ' 



A fowl may be mongrel in one respect and pure in another. 



