2 76 
differences may be developed in connection with the sub 
division of labour which occurs in connection with neuter 
insects. And inasmuch as different food and treatment 
result in the different issues of female and neuter insects, 
so it is not unreasonable to suppose that it may be with 
different kinds of neuters. The marvel of the whole 
theory is not lessened by such explanations, but they 
serve to establish an analogy between these and the more 
familiar phenomena of insect life. 
For the reasons which have just been assigned, I do 
not believe that instincts can have arisen or been modified 
by the action of Natural Selection in the case of those 
animals which are endowed with intelligence. Let us 
once more note what Mr. Romanes says upon this subject, 
quoting him a little more fully than heretofore. 
“ If we accept the theory of Natural Selection as of any validity at 
all in explaining the evolution of structures, it becomes simply 
impossible to dispute that it must also be of some validity in explain 
ing the evolution of instincts. For instincts, no less than structures, 
are of use to the animals possessing them ; like structures, they vary 
and are inherited ; like structures, therefore, and no less than 
structures, they are amenable to all those influences which are 
comprised in the term, ‘ survival of the fittest.’ And when, in 
addition to this, we find abundant proof of the intelligence of 
animals guiding the course of variation—so that, unlike the case 
of structures, instincts do not recpjire to wait for Natural Selection to 
seize upon fortuitous variations, but themselves supply variations 
which in relation to any change of environment are from the first 
adaptive—when we find this, we cannot fail to perceive that in no 
department of organic nature is Natural Selection operating at so 
much advantage. Lastly, when over and above all this we find 
abundant evidence of the principle of ‘lapsing intelligence’ co 
operating with that of Natural Selection, we must upon the whole 
conclude that, if the theory of evolution is of any validity in any 
case as a scientific interpretation of natural phenomena, nowhere is 
it more successful in this respect than it is in the domain of instinct.” 
—(.Fortnightly Review, vol. xxxviii., fip. 9J-4-) 
It should be observed that Mr. Romanes starts with 
the assertion that the influence of Natural Selection in