Studies on Inheritance in Poultry. 
453 
for the White Plymouth Rock $ $ (c 2 BbFfi 2 or BbFfi 2 X 2 Y 2 ) furnishes 
the better interpretation for the experimental results now to be 
reported. 
Experimental Results* 
In the breeding season of 1912 White Leghorn 1A, was mated 
with White Plymouth Rock $$, 270A and 288A. From this 
mating 63 chicks were hatched and the majority of them raised to 
the age of five or six months. Of the 63 Fi birds, five showed imper¬ 
fect barring in one or more feathers; many possessed feathers slightly 
flecked with black, indicating that the inhibitor I was not able, when 
in heterozygous condition, to hold in check all black pigmentation. 
In the breeding season of 1913, an Fief, 466C, was mated with 
four of his sisters, 466E, J, M and P. The male was a nearly pure 
white bird. Of the females, 466E, J and P were pure white, although 
as a chick 466J showed patches of black down feathers; 466M put 
up one barred feather among the right secondary coverts. 
This mating gave rise to 103 chicks. The majority were reared to 
the age of five or six months, and some to maturity. Among the 103 
birds were 21 which were either dark colored or possessed the barred 
pattern; in the majority of these the barring was of poor grade, but 
in a few it was fair. 
In the breeding season of 1914, a brother of the male employed 
in 1913 (466A) was mated with the three females that remained, 
466J, M and P. From this mating, 64 birds were hatched and 
described. Observations showed that 52 were white and 12 barred 
or dark colored. 
Discussion of Results. 
If the W. L. cT has the zygotic constitution C 2 B 2 f 2 I 2 as indicated on 
a previous page, it forms gametes 
CBfl . CBfl 
while the W. P. R. $, c 2 BbFfi 2 , forms gametes 
cBfi . cbFi. 
