e of
which is occupied by a male who passes the whole of his time therein.
Take whatever species we will--Whitethroat, Whinchat, Willow-Warbler,
Red-backed Shrike, it matters not which, for there is no essential
difference in the general course of procedure--this condition will be
found to prevail. Generally speaking, the behaviour in relation to the
territory can be studied more conveniently where a number of individuals
of the same species have established themselves in proximity to one
another. Such species as the Chiffchaff, Willow-Warbler, or Wood-Warbler
are often sufficiently common to allow of three or more of their
respective males being kept in view at the same time; and the
disposition to occupy a definite position can be readily observed. The
Reed-Warbler is a suitable subject for an investigation of this kind;
for since it is restricted by its habits to localities wherein the
common reed (_Arundo phragmites_) grows in abundance, and since such
localities are none too plentiful and often limited in extent, the area
occupied by each individual is necessarily small--if it were not so the
species would become extinct. Hence it is a simple matter to study the
routine of the different individuals and to mark the extent of their
wanderings.

In this way the males of all the Warblers that breed commonly in Great
Britain establish themselves, each one in its respective station at the
respective breeding ground; so, too, do those of many other
migrants--for example, the Whinchat, Wheatear, Tree-Pipit, and Red-backed
Shrike. All of these, it is true, are common species--numbers of
individuals can often be found in close proximity--and therefore it may
be argued that they keep to one position more from pressure of
population than from any inherited disposition working towards that end.
But the rarer species behave similarly. Districts frequented by the
Marsh-Warbler and offering plenty of situations of the type required by
the bird are often inhabited by a few members only, and yet the
disposition to remain in a definite position is just as marked.

You will say, however, that these smaller migrants have no exceptional
powers of flight; that they have besides just completed a long and
arduous journey; and you will ask why they should be expected to wander,
whether it is not more reasonable to expect that, in order to overcome
their fatigue, they should remain where they settle. The Cuckoo is a
wanderer in the wider s