EVOLUTION OF INSTINCTIVE. BEHAVIOUR 115 
There is, however, a way in which, when natural selection 
is operative, intelligence may serve to foster congenital varia- 
tions of the required nature and direction. We must re- 
member that acquired habits on the one hand, and congenital 
variations of instinctive behaviour on the other hand, are both 
working, in their different spheres, towards the same end, that 
of adjustment to the conditions of life. If, then, acquired 
accommodation and congenital adaptation reach this end by 
different methods, survival may be best secured by their co- 
operation. And the more thorough-going the co-operation 
the better the chance of survival. There would be a dis- 
tinct advantage in the struggle for existence when inherited 
tendencies of independent origin coincided in direction with 
acquired modifications of behaviour ; a distinct disadvantage 
when such inherited tendencies were of such a character as to 
thwart or divert the action of intelligence. Thus any here- 
ditary variations which coincide in direction with modifications 
of behaviour due to acquired habit would be favoured and 
fostered ; while such variations as occurred on other and 
divergent lines would tend to be weeded out. Professor Mark 
Baldwin,* who has independently suggested such relation 
between modification and variation, has applied to the process 
the term “Organic Selection ;” but it may also be described 
as the natural selection of coincident variations. 
It may be urged, therefore, that if natural selection be 
accepted as a potent factor in organic evolution, and unless good 
cases can be adduced in which natural selection can play no 
part and yet habit has become instinctive, we may adopt some 
such view as the foregoing. While still believing that there is 
some connection between habit and instinct, we may regard the 
connection as indirect and permissive rather than direct and 
transmissive. We may look upon some habits as the acquired 
modifications which foster those variations which are coincident 
in direction, and which go to the making of instinct. 
The net result of a study of instinctive behaviour is to lead 
* Professor Henry Osborn has also indicated the relationship re- 
ferred to. ca 
