1 6 INHERITAXCK IN POULTRY. 



First hybrid crossed with Minorca. All records give : 



Expectation, assuming complete dominance of black, is lOO per cent of 

 black individuals. Result shows incomplete dominance. Of the black-and- 

 white headed individuals, one is a female ; the other died too early for the 

 sex to be determined. Here, again, dominance is less perfect in the female. 



6. Correlation of Characters. — In the Single-comb Black Minorca 

 and in the White- crested Black Polish there is an assemblage of characters 

 that are nearly always associated in those races. The first hybrids have 

 another constant association unlike either of the parents, viz., split comb, 

 black crest (in the male) without cerebral hernia, and low to medium nos- 

 trils (fig. 6). In the second generation of hybrids, on the other hand, occur 

 combinations of characters both of the parental species and also of the first 

 generation of hybrids. These combinations are of the most varied sort, so 

 that characteristics always found associated in one parent species may here 

 be found dissociated. When hybrids are bred i>iter se the following com- 

 binations are obtained : 



Crest. 



Present . 

 Absent 

 Present . 

 Absent . 

 Pre.'eut. 

 Absent . 

 Present 

 Absent . 

 Present . 

 Absent . 

 Present . 

 Absent . 



Hernia. 



Nostril. 



Absent . 

 Absent . 

 Present 

 Present. 

 Absent . 

 Absent . 

 Present . 

 Present. 

 Absent . 

 Absent . 

 Present. 

 ; Present. 



■{ 



Narrow. 



High... 



Narrow . 

 \ High... 

 f : Narrow. 

 I High... 

 f ! Narrow, 

 t High... 

 f Narrow. 

 \ ! High . . . 

 / Narrow . 



High . 



Narrow . 



High... 



Narrow . 



High... 



Narrow . 



High . . 



Narrow . 



High 



Narrow 



High... 



Narrow . 



High... 



Number of cases. 



Actual. 



17 

 o 



8 

 o 

 I 

 o 



3 

 o 



8 



o 



12 

 O 

 2 

 O 

 O 



o 

 I 

 8 

 o 

 I 

 4 



5 

 o 

 o 



Calcu- 

 lated. 



15 

 5 

 5 

 1.6 



5 



1.6 



1.6 



0.5 



7-3 



2.5 



2.5 



0.8 



2.5 

 0.8 

 0.8 

 0-3 

 7.3 

 2.8 



2.5 

 0.8 



2.5 

 0.8 

 0.8 

 0.0 



