es and trees surrounding the field, rest there
and preen their feathers. But even though a male may be surrounded by
other males, even though it may occupy a position where it is
conspicuous to all around, even though, that is to say, it is
apparently in contact with just those stimulating circumstances which
will evoke a response when it returns to its territory, yet it makes no
attempt to sing.

Lapwings, when they resort to the neutral ground, run this way and that
in full enjoyment of one another's companionship, behaving as they do
when they flock in autumn and winter. Specific emotional manifestation
is, however, absent, and their actions seem to be in nowise affected by
the powerful impulse which only a few minutes previously determined
their conduct, for of the characteristic flight with its accompanying
cry there is no sign.

Early in the season Turtle Doves often collect from the surrounding
country at certain spots where their favourite food is abundant. The
croak of this Dove--its true song--is a familiar sound during the
summer, but in addition the bird has a sexual note characteristic of the
race. I watched a flock of upwards of one hundred on some derelict
ground approximately eight acres in extent. Here, in May, the birds were
attracted by the seeds of _Stellaria media_ which was growing in
profusion. After 5 A.M. there was continuous traffic between this piece
of ground and the surrounding neighbourhood, a constant arrival and
departure of single individuals or pairs; and, as they fed, the sexual
note could be heard in all directions. Now some of the males occupied
territories close at hand, and one could watch their passage to and
fro; yet in no single instance did I hear the true song uttered on the
feeding ground, although the moment a male returned to its territory its
monotonous croak could be heard, uttered moreover with that persistence
which is so marked a feature of all song or of the sounds that
correspond to it.

Thus it will be seen that, even after the internal organic changes have
taken place, the instinct of song is not susceptible to stimulation at
all times and under all circumstances, but only at certain specified
times and under special circumstances which can be observed to
correspond with the occupation of the territory.

In many species each male singles out within its territory some
prominent position to which it resorts with growing frequency. This
position is an important f