rusting its bill deep in the earth in search of its daily food. This,
on the face of it, looks like a reasonable explanation, but it should be
borne in mind that not only do some individual rooks retain through
life the feathers normally missing, but that several of the rook's
cousins dip into Nature's larder in the same fashion without suffering
any such loss. However, the featherless patch on the rook's cheeks
suffices, whatever its cause, as a mark by which to recognise the bird
living or dead.

Unlike its cousin the jackdaw, which commonly nests in the cliffs, the
rook is not, perhaps, commonly associated with the immediate
neighbourhood of the sea, but a colony close to my own home in
Devonshire displays sufficiently interesting adaptation to estuarine
conditions to be worth passing mention. Just in the same way that gulls
make free of the wireworms on windswept ploughlands, so in early summer
do the old rooks come sweeping down from the elms on the hill that
overlooks my fishing ground and take their share of cockles and other
muddy fare in the bank uncovered by the falling tide. Here, in company
with gulls, turnstones, and other fowl of the foreshore, the rooks strut
importantly up and down, digging their powerful bills deep in the ooze
and occasionally bullying weaker neighbours out of their hard-earned
spoils. The rook is a villain, yet there is something irresistible in
the effrontery with which one will hop sidelong on a gorging gull, which
beats a hasty retreat before its sable rival, leaving some half-prized
shellfish to be swallowed at sight or carried to the greedy little beaks
in the tree-tops. While rooks are far more sociable than crows, the two
are often seen in company, not always on the best of terms, but usually
in a condition suggestive of armed neutrality. An occasional crow visits
my estuary at low tide, but, though the bird would be a match for any
single rook, I never saw any fighting between them. Possibly the crow
feels its loneliness and realises that in case of trouble none of its
brothers are there to see fair play. Yet carrion crows, like herons, are
among the rook's most determined enemies, and cases of rookeries being
destroyed by both birds are on record. On the other hand, though the
heron is the far more powerful bird of the two, heronries have likewise
been scattered, and their trees appropriated, by rooks, probably in
overwhelming numbers. Of the two the heron is, particularly in t