THE CONSCIOUS ASPECT 105 
thither in short quick spurts, and so forth. No doubt in such 
cases external stimuli are present, and contribute in some 
degree to the effects produced; but they do not seem to be 
particularized so that one can say that just this or that well- 
defined stimulus is necessary to give rise to the observed 
behaviour. In the case of migration, too, an internal factor— 
the nature of which we do not know—is probably as strong 
as if not stronger than any influence from without. While, 
therefore, we may say that some external factors are frequently, 
not improbably always, contributory, we must add that observa- 
tion does not enable us in all cases to define them with any 
approach to accuracy; and, further, that promptings from 
within seem in some instinctive acts to be the most important 
elements in the conscious situation. 
It now only remains to draw attention to the fact that the 
effects of the behaviour, as the animal becomes conscious of 
the performance of the acts concerned, serve to complete and 
render definite the conscious situation. Consciousness, how- 
ever, probably receives information of the net results of the 
progress of behaviour, and not of the minute and separate 
details of muscular contraction. These net results, having 
thus entered presentatively into the situation, are subsequently 
susceptible of re-presentative recall, when the recurrence of 
certain salient elements serve to reproduce the essential features 
of the situation of which experience has been gained on a 
former occasion. Hence, as has already been noted, it is only 
the first performance of an instinctive action which can be 
described as prior to experience. The second time the deed is 
done it is done by an animal which has had opportunity of 
gaining experience on the foregoing occasion. And then it 
may be done with a difference, with some acquired modification 
of performance. By the repetition of the slightly modified be- 
haviour the effects of habit are introduced, and thus acquired 
peculiarities of action are established as individual traits. We 
must not forget that, in a large number of cases, so-called 
instinctive behaviour, as presented to observation, has lost 
through modified repetition its original purity of type. The 
