CROSSING PRODUCTION AND EXHIBITION BIRDS 11 



Table 5. -Classification of Exhibition Stock and of Hybrid Offspring 

 According to Surface Color and Smut 



from exhibition males showed smut. Smutty birds were confined almost ex- 

 clusively to the group with medium or darker surface color. 



In the F2 generation there was something of a tendency for smut to segregate 

 with light surface color, but the majority of males and females carrying smut 

 were classed as having medium or darker surface color. In this second genera- 

 tion 42 per cent of the males and 39 per cent of the females showed smut. Thus 

 the proportion of smutty birds in the second generation was about midway be- 

 tween that of the two classes of Fi progeny. 



The data for class 4 progeny are very limited but they suggest that smut is 

 more likely to occur in birds with the darker shades of surface color. 



When production males were mated to Fi females (class 5), there was a tend- 

 ency for smut to occur with the dominant lighter shades of surface color, espec- 

 ially in female progeny. 



The same general situation with respect to smut and surface color was noted 

 in the class 6 progeny from exhibition males and Fi females; namely, that when 

 smut occurred in birds with light surface color it appeared first in females. 



The limited data presented for class 7 also give evidence that smut is more 

 likely to appear with light surface color in females than in males. 



The data for class 8 indicate greater freedom from smut in females than in 



