The Descent of Man

As far, then, as gradation throws light on the
steps by which the magnificent train of the peacock
has been acquired, hardly anything more
is needed. If we picture to ourselves a progenitor
of the peacock in an almost exactly intermediate
condition between the existing peacock,
with his enormously elongated tail-coverts,
ornamented with single ocelli, and an ordinary
gallinaceous bird with short tail-coverts, merely
spotted with some colour, we shall see a bird
allied to Polyplectron—that is, with tail-coverts,
capable of erection and expansion, ornamented
with two partially confluent ocelli, and long
enough almost to conceal the tail- feathers, the
latter having already partially lost their ocelli.
The indentation of the central disc and of the
surrounding zones of the ocellus, in both species
of peacock, speaks plainly in favour of this
view, and is otherwise inexplicable. The males
of Polyplectron are no doubt beautiful birds,
but their beauty, when viewed from a little distance,
cannot be compared with that of the pea-