SO INTERNAL ANATOMY OF INSECTS. 
doubt the possibility of satisfactorily explaining the va- 
riety of instincts exercised by a bee a , or the extraordi- 
nary development of new ones in particular circum- 
stances only b , on any merely mechanical grounds. 
And after all, even suppose it could be demonstratively 
shown that every instinct is as clearly dependent on se- 
condary causes, as I have formerly admitted that some 
doubtless seem to be, yet what would this teach us as 
to the essential nature of instinct ? We have advanced 
indeed a step; but still, as I have before observed in re- 
ferring to the theories of Brown and Tucker, we have 
only placed the world upon the tortoise, and instinct, as 
to its essence, which is what we want to detect, is as my- 
sterious as ever : just as, though we can clearly prove 
that the mind is acted upon by the senses, yet this throws 
no light upon the essential nature of the mind, which we 
are forced to admit is inscrutable, as if to teach us hu- 
mility, and prevent our vainly fancying, that though 
allowed to discover some of the arcana of nature, we 
shall ever be able to penetrate into her inmost sanctu- 
aries. 
That Dr. Virey should regard instinct in insects as 
purely mechanical was the natural consequence of his 
denying them any portion of intellect ; but his opinion 
cannot I think be consistently assented to, if it be the 
fact, as I have just shown c , that they are not wholly de- 
void of the intellectual principle. Whatever is merely 
mechanical, must, under similar circumstances, always 
act precisely in the same way. An automaton once con- 
structed, whilst its machinery remains in order, will in- 
variably perform the same actions; and Des Cartes, when 
■ Vol. II. p. 40.3. b Ibid. p. . r >(W. c See above, p. 21. 
