INSTINCT OF INSECTS. 



381 



no massacre of the drones takes place ? Lastly, to omit here 

 a hundred other instances, as many of them will be sub- 

 sequently adverted to, if we may with some show of reason 

 suppose that it is the sensation of heat which causes bees to 

 swarm ; yet what possible conception can we form of its being 

 bodily sensations that lead bees to send out scouts in search 

 of a hive suitable for the new colony several days before 

 swarming ? 



After these observations on the nature of instinct, gener- 

 ally, I pass on to contrast in several particulars the instincts 

 of insects with those of other animals; and thus to bring 

 together some remarkable instances of the former which have 

 not hitherto been laid before you, as well as to deduce from 

 some of those already related inferences to which it did not 

 fall in with my design before to direct your attention. This 

 contrast may be conveniently made under the three heads 

 of the exquisiteness of their instincts, their number, and their 

 extraordinary development. 



The instincts of by far the majority of the superior animals 

 are of a very simple kind, only directing them to select suit- 

 able food ; to propagate their species ; to defend themselves 

 and their young from harm ; to express their sensations by 

 various vocal modulations ; and to a few other actions which 

 need not be particularised. Others of the larger animals, in 

 addition to these simpler instinctive propensities, are gifted 

 with more extensive powers ; storing up food for their winter 

 consumption, and building nests or habitations for their young, 

 which they carefully feed and tend. 



All these instincts are common to insects, a great propor- 

 tion of which are in like manner confined to these. But a 

 very considerable number of this class are endowed with in- 

 stincts of an exquisiteness to which the higher animals can lay 

 no claim. What bird or fish, for example, catches its prey 

 by means of nets as artfully woven and as admirably adapted 

 to their purposes as any that ever fisherman or fowler fabri- 

 cated ? Yet such nets are constructed by the race of spiders. 

 What beast of prey thinks of digging a pitfall in the track of 

 the animals which serve it for food, and at the bottom of 

 which it conceals itself, patiently waiting until some unhappy 



