The Descent of Man

teris and night-jar (Eurostopodus), see Gould's
'Handbook to the Birds of Australia,' vol. i. pp.
602 and 97. The New Zealand shieldrake (Tadorna
variegata) offers a quite anomalous case;
the head of the female is pure white, and her
back is redder than that of the male; the head of
the male is of a rich dark bronzed colour, and
his back is clothed with finely pencilled slatecoloured
feathers, so that altogether he may be
considered as the more beautiful of the two. He
is larger and more pugnacious than the female,
and does not sit on the eggs. So that in all these
respects this species comes under our first class
of cases; but Mr. Sclater ('Proceedings of the
Zoological Society,' 1866, p. 150) was much
surprised to observe that the young of both
sexes, when about three months old, resembled
in their dark heads and necks the adult males,
instead of the adult females; so that it would
appear in this case that the females have been
modified, whilst the males and the young have
retained a former state of plumage.)