242 PRINCIPLES OF POULTRY BREEDING 



There is also a relation between the color of the comb and 

 wattles and the health and vigor of the bird, the latter being asso- 

 ciated with a bright red comb, and disease or lack of vigor with 

 a dull color or lack of color. 



In different breeds there is a definite relation between the size 

 and weight of the body and the development of wings. In the 

 lighter breeds this results in powers of flight which are lacking in 

 the heavier breeds. 



Many false notions as to correlation are often advanced. For 

 instance, there is a belief that the color of the skin indicates the 

 quality and flavor of the flesh; that the color of eggs hells influences 

 the quality of the contents; that white birds are often of weaker 

 constitution than pigmented birds, all of these are without sub- 

 stantial proof. 



Body Character and Functional Activity. Poultry breeders and 

 experimenters have for a number of years persistently endeavored 

 to find some correlation between egg production and some readily 

 detected external characteristics, but with little success. As was 

 previously stated, egg production seems to be an inherited func- 

 tion based on the gametic constitution of the individual, and has 

 not been consistently indicated by any other factor. A bright red 

 comb, full bright eyes, erect carriage, compact and solid body are 

 all signs of the vigor and vitality which are necessary for heavy 

 egg production, but none can be said to be always associated 

 with it. 



The author has noted a consistent relation between shape of 

 barrel or body and the power of reproduction. Heavy egg pro- 

 duction was found to be associated with great depth and breadth 

 of body in proportion to its length. There is need for much 

 statistical work to test such a relationship, and accurate results 

 cannot be claimed until a great number of individuals have been 

 studied. Wherever it is possible to associate certain external 

 features with functional activity or vitality or constitution, it is 

 a simple matter to put into practice a rigid selection, using only 

 birds which show this external character. 



Prepotency. By prepotency is meant the increased power 

 which one parent has over the other of imparting its characteristics 

 to the offspring. It is really the power which an individual has 

 to transmit its own characteristics. This question of prepotency 

 is of the utmost value to the breeder, because of the direct influence 

 which it is bound to have upon the improvement of his flock, 



