Mutations among Birds 
The Golden Pheasant (Chrysolophus pictus) 
produces, in domestication, the dark-throated 
form (C. odscurus), in which the cock has the 
throat sooty-black instead of buff, and the 
scapulars or shoulder feathers black instead of 
red. Moreover, the two middle-tail-feathers are 
barred with black and brown like the lateral 
ones, while in the ordinary form they are spotted 
with brown on a black ground. The hens have 
a chocolate-brown ground-colour instead of 
yellow-ochre as in the normal type. The 
chicks are likewise darker. 
The common duck, in domestication, when 
coloured like the wild mallard, sometimes pro- 
duces a form in which the chocolate breast and 
white collar of the drake are absent, the pencilled 
grey of the abdomen reaching up to the green 
neck. In this mutation the duck has the head 
uniformly speckled black and brown, and lacks 
the light eye-brow and cheek-stripes found in 
the normal duck. Both sexes have the bar on 
the wing dull black instead of metallic blue. 
The ducklings which ultimately bear this 
plumage are sooty-black throughout, not black 
and yellow like normal ones. 
The phenomenon of mutation is not confined 
to animals in a state of domestication. The 
common Little Owl of Europe (Athene noctua) 
has produced the mutation 4. chiaradie in the 
wild state. In this the irides are dark, instead of 
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