the more pugnacious, and will
attack any other Warbler that approaches too closely; Whitethroats are
often pursued and driven away, and less frequently, Garden-Warblers. In
one case, a male occupied the same ground as a Sedge-Warbler, and there
was a constant feud between them; a willow-tree formed its headquarters,
and this same tree seemed to be the headquarters of the Sedge-Warbler,
so that they often met and whenever they did so they quarrelled. As a
rule the Marsh-Warbler was the aggressor and had the mastery over its
opponent, and when it attacked, it uttered a peculiar harsh scolding
note, raised the feathers on its back, spread out its wings, and
betrayed the usual symptoms of emotional excitement.

On the other hand, the Sedge-Warbler is most aggressive towards other
kindred species, and when a male happens to occupy the same ground as a
Reed-Warbler, there are frequent battles between them and incessant
commotion; they fly at one another and meet in the air with an audible
clicking of bills, or pursue one another amongst the reeds, each one
uttering its characteristic scolding note.

The Tits, as a family, are notoriously pugnacious. I have seen a pair of
Blue Tits attack a single Long-tailed Tit with great determination, and
not only did they pursue it, but, flying at it, struck it with
considerable force.

In giving an account of the domestic economy of the Carrion-Crow, Mr.
Edmund Selous refers to the hostility between this bird and the Magpie.
"About a week ago," he says,[6] "I saw a Crow busily engaged in chasing
away several Magpies, not only from three or four tall slender trees
close together, in one of which it had its nest, but also from various
other trees, not far off, round about. In this the Crow had a good deal
of trouble, as the Magpies were always returning. After a time it was
joined by another crow, which however did not take so active a part in
the drama, nor did I see either of the two actually go to the nest,
though I could only explain their action by supposing it was their own.
This morning I saw the same thing reversed, for a pair of Magpies, with
an undoubted nest, kept attacking a Crow that insisted on settling in
one of a row of trees--also tall and slender--in which it was placed.
Both were equally persevering--the Crow, though often chased away,
always returning, and settling generally in the last tree of the row,
where he would be left alone sometimes for a minute or two, but b