122 INTELLIGENT BEHAVIOUR 
one, though, when disclosed, it almost immediately sets to 
work to make funnels on the complex and perfect system” 
characteristic of the species. This is but one example of 
instinctive precision out of the many which could be cited. 
We may say, then, that though, when an act is otherwise 
shown to be intelligent, the precision is a criterion of the 
level attained by the intelligence, still it cannot be said to 
be a criterion which serves to distinguish intelligent from 
instinctive behaviour. 
Nor can we regard apparent prevision (which is sometimes 
advanced as a criterion of intelligence) as specially distinctive 
of intelligent acts regarded objectively in the study of animal 
behaviour. For, as we have had occasion to show, there are 
many instincts which display an astonishing amount of what 
may be termed “blind prevision”—instance the instinctive 
regard for the welfare of unborn offspring which the mother 
will never see, and the instinctive preparation for an unknown 
future existence in the case of insect larve. 
Nor, again, is the complexity of the adjustment distinctive 
of intelligence as contrasted with instinct. We have cited 
examples which afford evidence of much complexity in in- 
stinctive behaviour. The construction and storage of the 
nest among solitary wasps, and their methods of capturing 
and conveying the insects or spiders on which they prey, are 
sufficiently complex. So, too, is the behaviour of the Sitaris 
larva which attaches itself to the male hee, passes to the 
female, and then slips on to the eggs she lays; and so, again, 
is that of the Yucca moth, which collects pollen from the 
anthers, conveys it to the stigma, and then lays her eggs 
among the ovules. These cases show, too, that the circum- 
stances may be dealt with in such a way as to extract from 
them the maximum of benefit. It would be difficult intelli- 
gently to improve upon the manner of dealing with the.circum- 
stances displayed in many familiar modes of instinctive procedure. 
There remain the novelty of the adjustment and the in- 
dividuality displayed. And here we seem to have valid 
criteria of intelligent behaviour. The ability to perform 
