62 



Combs of Fowls 



[CH. 



lateral ridge. These two lateral ridges together with the 

 median one constitute the three ridges commonly spoken of 

 as the essential feature of the pea comb. The size and 

 details of development of these combs differ a good deal 

 with individuals and with strains. Pea comb is especially 

 characteristic of Indian Game, Aseel, and the Brahma 

 breeds. 



The FI from pea x single is pea, that character mani- 

 festing a definite dominance. The heterozygous pea combs 

 are generally higher than the pure pea and may usually, 

 though not always, be distinguished from them. Sometimes 

 the heterozygous pea comb is so large and has the ridges 

 so ill-defined that it approaches the single type, but combs 

 which cannot at once be referred to one class or the other 

 are extremely rare. The distinction is especially sharp in 

 the case of the newly hatched chicks, becoming somewhat 

 less marked with later development. F % from this cross is 

 of the usual form, 3 pea : i single. 



Fig. 13. The combs as they appear in newly hatched chickens. 



In the top row from left to right : Walnut comb in a light- 

 coloured bird, showing the peculiar band of hairs ; ditto in a dark- 

 coloured bird ; Rose comb. 



In lower row from left to right : Pea comb ; ditto ; Single comb ; 

 ditto. 



