SEX INHERITANCE 107 
characters are not sex-linked since they are not 
associated with a particular sex-chromosome, yet 
they may be said to be ‘“‘sex-limited.”’ 
The first case is that of hen-feathering, shown 
by certain breeds of poultry. In Sebright bantams 
the males (Fig. 36, a) are hen-feathered. If either 
a male or a female Sebright is crossed to a race 
with normal cock-feathering the male offspring are 
hen-feathered. In the F, generation there are both 
or b 
Fig. 36.—a, Normal Sebright hen-feathered cock. 6, castrated 
Sebright cock. 
cock-feathered and hen-feathered males. This shows 
that the dominant factors for hen-feathering are 
not in the sex-chromosomes, for, if they were, the 
F, generation from one cross would give only hen- 
feathered males, and from the reciprocal cross both 
kinds of males. 
If a hen-feathered male is castrated the new 
feathers that come in—immediately if old feathers 
are plucked, otherwise at the next molt—are cock- 
feathered (Fig. 36, b). It is obvious that something 
