The Descent of Man

ock's keepers. (5. On magpies, Jenner, in 'Philosophical
Transactions,' 1824, p. 21. Macgillivray,
'Hist. British Birds,' vol. i. p. 570. Thompson,
in 'Annals and Magazine of Natural History,'
vol. viii. 1842, p. 494.) The first and most
obvious conjecture is that male magpies must
be much more numerous than females; and that
in the above cases, as well as in many others
which could be given, the males alone had been
killed. This apparently holds good in some instances,
for the gamekeepers in Delamere Forest
assured Mr. Fox that the magpies and carrioncrows
which they formerly killed in succession
in large numbers near their nests, were all males;
and they accounted for this fact by the males
being easily killed whilst bringing food to
the sitting females. Macgillivray, however, gives,
on the authority of an excellent observer,
an instance of three magpies successively killed
on the same nest, which were all females; and
another case of six magpies successively killed
whilst sitting on the same eggs, which renders