SEX-LINKED INHERITANCE 439 
in domestic fowls, pigeons, ducks, and canaries. As an example we 
may take the inheritance of the color pattern, barring, in crosses of 
barred Plymouth Rock fowls. In reciprocal crosses between pure- 
bred barred Plymouth Rocks and black Langshans (or another 
unbarred breed), the results are not identical. If the barred parent is 
the male (Fig. 91 and Table III), all F, offspring are barred and in F, 
all males are barred, but half the females are black and half are barred. 
If, however, the barred parent is the female (Fig. 92 and Table IIT), 
TABLE III 
RecrprocaL Crosses OF BARRED AND BLACK BREEDS OF FowLs 
Male Female Male Female 
P Barred X _ Black Black x Barred 
F, Barred Barred Barred Black 
F, Barred 1 Barred: 1 Black 1 Barred: 1 Black 1 Barred: 1 Black 
(See Fig. gr) (See Fig. 92) 
Fic. 92.—Reciprocal cross to that shown in Figure 91. P, parents, unbarred 
male, barred female; F,, barred males, unbarred females (crisscross inheritance); 
F,, barred and unbarred birds equally numerous in both sexes. (From Castle.) 
