ense of the term, and is gifted with considerable
powers of flight. Upon arrival the male flies briskly from field to
field, showing but little signs of weariness; yet we have only to follow
its movements for a few days in succession to assure ourselves that the
bird is no longer a wanderer; for just as the Warbler or the Chat moves
only within a definitely delimited area, so the male Cuckoo, strange as
it may seem, restricts itself to a particular tract of land. The area
over which it wanders is often considerable and consequently it is not
possible to keep the bird always in view, but inasmuch as the variation
in the voices of different individuals is quite appreciable,
identification is really a simple matter. If we cannot keep the bird in
sight, we can trace its movements by sound and mark the extent of its
wanderings, which by repetition become more and more defined, until a
belt of trees here, or an orchard there, mark a rough and rarely passed
boundary line.

Let us take another example from the larger migrants--the Black-tailed
Godwit, a bird common enough in the Dutch marshes but no longer breeding
in this country. On suitable stretches of marsh land, numbers will be
found in proximity one to another after the manner of the Lapwing, each
male occupying a definite space of ground wherein it passes the time
preening, searching for food, or in sleep--though at the same time
keeping a strict watch over its territory. Now the preference shown for
a particular piece of ground, and the determination with which it is
resorted to, is the more remarkable when we take into consideration the
specific emotional behaviour arising from the seasonal sexual condition.
This behaviour is expressed in a peculiar flight. The bird rises high in
the air, circles round with slowly beating wings above the marsh, and
utters a call which, as far as my experience goes, is characteristic of
the performance. The air is often full of individuals circling thus
even beyond the confines of the marsh, for a male does not limit its
flight to a space immediately above its territory; but nevertheless
careful observation will show how unerringly each one returns to its own
position on the breeding ground, no matter how extensive the aerial
excursion may have been. And so, when the males of the smaller migrants
confine their movements to an acre of ground at the completion of their
long journey, they are acting no more under the influence of fatigue