e detection; and, which is
still more curious, a covey of Partridges will evoke response if they
approach the pool too closely.

Here is a curious instance of apparent waste of energy. A pair of
Magpies built their nest in an ilex tree. Early one morning there was a
commotion in the tree, much flapping of wings and a medley of sounds
which told of large birds engaged in a struggle--the Magpies were
attacking a pair of Wood-Pigeons. There was no question as to the
genuineness of the struggle, nor any doubt as to the proximate end for
which the Magpies were striving, for their efforts continued so long as
the Wood-Pigeons remained in the tree, and only ceased when they had
succeeded in driving them away.

Turning next to species which are less distantly related, we find that
instances of intolerance are more numerous and that a wider range of
species is involved. The hostility that the Lapwing displays towards the
Snipe calls for special remark. It often happens that the marshes or
water meadows, that are such favourite haunts of the Lapwing, are also
resorted to by Snipe for the purpose of securing food, or it may be even
for the purpose of reproduction. In such places both species are often
abundant; the meadow is divided up into Lapwings' territories, and early
in the season the Snipe wander over it in small parties, singly, or in
pairs. Now, if it were only on isolated occasions that the Lapwing paid
heed to the Snipe, one would not perhaps attach any peculiar
significance to the fact; but the pugnacious instinct of the bird
responds to the presence of this intruder almost as freely as it does to
that of another Lapwing. Again and again, day after day, the Snipe are
attacked and driven off in a manner which would be fittingly described
as persistent persecution, for the Snipe has neither the physical
capacity nor apparently any instinctive tendency to retaliate. Thus a
Lapwing may come suddenly upon a small party of Snipe hidden from view
in a dyke where they are probing the ground for food; the Snipe
immediately rise and fly away and there is momentary confusion as the
Lapwing darts first at this one, then at that; or, espying a Snipe at
rest at the opposite end of its territory, it will first of all run
rapidly towards it, and then fly after it, as, with twisting flight, it
darts hither and thither a few feet above the ground; or again, it will
attack and rapidly pursue solitary individuals as they skim across its