36 BREEDING 



character behaves as a simple dominant when it 

 meets the dwarf character, in a cross. 



But the case exhibited by the Andalusian fowl 

 is different. The so-called blue colour of this bird 

 may, or may not, be described as an intermediate 

 between the black and white of the fowls which 

 produce it when they are crossed ; but, at any rate, 

 it is different from either of them, and the important 

 point to note is that the hybrid, whether of the first 

 or second or third hybrid generation, is distinguished 

 from both of the parents of the cross, not only by 

 its breeding properties, but by easily observable 

 external characteristics. 



The reader will probably admit the reasonableness 

 of referring to the black fowl as the dominant, and the 

 white as the recessive, although the black is not 

 absolutely dominant over the white in the result of 

 the cross. It is expedient to use these terms in this 

 case, because it is convenient to have a general term 

 to apply to the characters of the two forms crossed. 

 It is also legitimate to use them because the diSerence 

 between the result of crossing the black and the 

 white fowl and the result of crossing the tall and 

 dwarf pea is only one of degree. In the case of the 

 pea, tallness is completely dominant over dwarf ; in 

 the case of the fowl blackness may be said to be only 

 partially dominant over whiteness. Moreover, it may 

 be that the appearance of complete dominance is 

 merely due to the fact that we are as yet unable to 

 detect the difierence between the hybrid and the 

 dominant in the case of stature in peas. This is no 



