io6 BREEDING 



are will be indicated shortly. For the present, let us 

 observe the result of their union. It will be at once 

 noted that we cannot, as in the case of the peas, 

 observe the co-existence of the two characters 

 *' rose " and " pea " in the hybrid. But this should 

 give no cause for surprise. In the case of the peas, 

 one pair of characters relates to colour and the other 

 to shape ; so, not only is it natural to expect to 

 see them separately in the hybrid, it is impossible 

 to imagine how they could become merged. But in 

 the case of the fowls' combs, both the characters 

 relate to shape, and it is therefore hard to conceive 

 how, when they both exist in the same comb, they 

 can escape blending, or at any rate producing a 

 shape which is different from either, and in which 

 neither can be recognised separately. 



The " walnut " character is, therefore, due to the 

 co-existence in the same comb of the " pea " and 

 " rose " types. The " single " comb, which makes 

 up one-sixteenth of the second hybrid generation 

 we are considering, is the result of the absence of 

 the two characters " pea " and " rose." The case is 

 entirely analogous to that of the peas : the yellow 

 rounds have two dominant characters ; so has the 

 " walnut," namely, " pea " and " rose " ; the yellow 

 wrinkled has one dominant character and one reces- 

 sive ; so has the " pea," namely presence of the 

 " pea " character, and absence of the " rose " — if 

 the " rose " were present the comb would be 

 " walnut." The green round also has one dominant 

 character and one recessive ; so has the " rose," 



