8 



C. B. DAVENPORT 



and '11) has studied sex-limited barring in Barred Rock X Buff 

 Rock and Barred Rock X Brown Leghorn crosses. In general 

 the results of these matings, on the new hypothesis, are as indi- 

 cated in table 4, where B stands for the barring factor and h for 

 its absence. 



5. That the black and red markings of the Brown Leghorn 

 and the gray of the White Wyandotte are also sex-limited is 

 maintained by Sturtevant ('11) in a brief notice. When the 

 Brown Leghorn was used as the father the eight daughters were 

 all brown ; but in the reciprocal cross they (all three) were gray; 

 the male offspring were gray in both crosses. 



TABLE 4 

 Inheritance of barring in barred X non-barred matings 



Fi (barred cf X non-barred 9 ) X Fi (barred cf X non-barred 9 ) 



Gametes 



B 

 b 



BB 

 Bb 



All d'c^ barred; fe- 

 males, 50 per cent 

 barred; 50 per cent 

 non-barred 



4 Fi (non-barred cf X barred 9 ) X Fi (non-barred cf X barred 9 ) 

 _ fB b 



Gametes 



50 per cent of cfcf 

 and 50 i^er cent of 

 9 9 non-barred; the 

 others barred 



