The Descent of Man

lue, indented centre, surrounded by a rich
green zone, this by a broad coppery-brown
zone, and this by five other narrow zones of
slightly different iridescent shades. A trifling
character in the disc deserves notice; the barbs,
for a space along one of the concentric zones
are more or less destitute of their barbules, so
that a part of the disc is surrounded by an almost
transparent zone, which gives it a highly
finished aspect. But I have elsewhere described
(50. 'Variation of Animals and Plants under
Domestication,' vol. i. p. 254.) an exactly analogous
variation in the hackles of a sub-variety of
the game- cock, in which the tips, having a metallic
lustre, "are separated from the lower part
of the feather by a symmetrically shaped transparent
zone, composed of the naked portions of
the barbs." The lower margin or base of the
dark-blue centre of the ocellus is deeply indented
on the line of the shaft. The surrounding
zones likewise shew traces, as may be seen in
the drawing (Fig. 54), of indentations, or rather