96 INSTINCTIVE BEHAVIOUR 
accurately related to movements in the visual field, the whole 
performed without any opportunity for learning or practice, 
and less than half an hour after the bird was taken from the 
drawer of the incubator and first saw daylight. Psychologists 
sometimes puzzle their heads over the question how and by what 
steps the field of vision and the field of movement are brought 
into relation with each other; but in such a case as this, the 
problem ceases to be primarily psychological. The relation is 
purely organic ; the conscious data are grouped from the outset. 
With young jays there was no such co-ordination at first ; and 
when they began after a few days (about twelve or fourteen) to 
follow an object with the head and eye, the movements were at 
first jerky. But a week later, when I swept the food through a 
circle a foot in diameter in front of their cage, it was followed 
smoothly and evenly. Here a certain amount of learning and 
practice, absent in the case of the pheasant, was required. 
And it is difficult to say what proportion of the final result 
was acquired, what proportion hereditary ; but probably the 
behaviour is in the main instinctive, though somewhat 
deferred. 
One more example, perhaps even more trivial in the eyes 
of some people, may be given. A duckling a few hours old 
will scratch the side of his head. It is true he may topple 
over in the process, through insufficient powers of balance, for 
the simultaneous performance of poising on one leg and having 
a good scratch with the other is no easy matter. But let not 
either our familiarity with such behaviour, nor some observed 
and laughable failure on the part of the duckling, blind us to 
the fact that this is a congenital activity, and one of no little 
complexity, indicating a definite organic nexus. A local irri- 
tation sets agoing movements of the hind limb of that side 
through which just that particular spot is scratched in the 
absence of any previous practice, any learning to localize the 
spot. There can be no question that such inherited co-ordi- 
nations, whether perfect from the first, or with deferred per- 
fection and some aid from acquisition, afford ready-made data 
to consciousness, which are of the utmost service in the 
