566 
Journal of Agricultural Research 
Vo!. XXni, No. 7 
WILD BY BERKSHIRE CROSS 
All the 17 Fj pigs which composed this cross were fairly uniform and 
striped, and, except in two particulars, closely resembled the wild X Tam- 
worth F, pigs. They had much less of a reddish tinge throughout and 
showed a number of large black spots along the underline and on the 
face, ears, and legs. The lack of the reddish tinge made the dark stripes 
appear a blacker brown and the light stripes and underline a very light 
g*?y- Th e black spotting was different in appearance from that in the 
wildXTamworth F 2 and back-cross pigs in two particulars; first, the 
spots were larger, usually being from i to inches in diameter on the 
new-born pigs, while those on the pigs of the Tamworth cross were 
rarely more than inch in diameter; secondly the spots on the latter 
tended to be restricted to the rear half of the animal, being especially 
frequent on the thighs and on the underline behind the umbilicus, while 
the larger spots on the pigs of the Berkshire cross appeared with almost 
equal frequence on all parts of the underline and lower sides, although 
perhaps a little oftener on the lower law, the side of the face, and the 
lower half of the ears. 
From these data it seems that the Berkshire lacks the factors deter¬ 
mining the deeper red color which the Tamworth possesses and has 
either a different fundamental factor or quite different modifying factors 
for black spotting because this spotting shows up at once in the F t 
generation of the wild X Berkshire cross and because it is different in 
appearance. 
Ufa BERKSHIRE by TAMWORTH CROSS 
P The io F t pigs composing the only litter of this cross consisted of 8 
which were red with one or more small black spots and 2 which were 
self-red. The red varied in intensity from a reddish gray to a dark 
reddish brown. Four of the 8 had many small black spots, 3 had only 
a few, and 1 had but a single black spot on the side of her nose. There¬ 
fore, it seems possible that there was no genetic difference between the 
2 self-red pigs and the 8 with black spots in regard to the fundamental 
factor for black spotting, the variation being due to differences in devel¬ 
opment or differences in modifying factors for restriction of black. 
These pigs had, on the average, fewer and smaller spots and were of a 
deeper red body color than the F x pigs from the Berkshire by Duroc- 
Jersey cross to be discussed next. 
BERKSHIRE BY DUROC-JERSEY CROSS 
The Duroc-Jersey, as a breed, shows considerable variation in the 
shade of red, but the sows of the parental generation of this cross were 
of medium color, neither very light nor very dark. The one whose son 
and daughters were used to produce the F 2 generation and that was her¬ 
self the dam of all the back-crossed litters was the desired cherry red. 
She was a good specimen of Duroc-Jersey brood sow and typical of the 
breed in every way except, perhaps, that she was chuffier than the 
breeder desires and her face was a little more dished than the average 
of the breed. 
The 29 pigs composing the F, generation all possessed small black 
spots scattered irregularly over a yellowish red (in most cases, sandy) 
body color. The black spots appeared a little more numerous on the 
