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which is an organ analogous to the trunk, and endued 

 with the same essential functions. 



Several species have two of those instruments united 

 in them ; sometimes the teeth and the trunk, and some- 

 times the trunk and the sting. Many species of insects 

 are deprived of the use of sight. With them the feeling, 

 or some other sense, supplies the defect of eyes. 



The eyes of insects are of two kinds : the smooth 



ones are always few in number ; the rough commonly 

 amount to several thousands, and are fixed on the sides 

 of the head, in the form of two semicircular masses. 

 In both of them they are utterly immoveable ; and their 

 number compensates, in some measure, the want of mo- 

 bility : it is, therefore, less a mark of perfection than of 

 imperfection. Many species have, at the same time, 

 two smooth eyes, and two rough ones. 



. Hearing seems to be denied to insects : at least, the 

 existence of this sense in them, is very doubtful. 



The case is not the same with respect to smelling. 

 Divers insects have it in an exquisite manner ; but the 

 seat of it is not known. May it not be situate in those 

 two moveable horns called the antennae, whose use we 

 are yet unacquainted with ? 



The legs of insects are scaly and membranous. Those 

 are moved by the assistance of divers articulations; 

 while these, which are more pliable, are turned every 

 way without difficulty. These two sorts of legs are 

 often united in the same worm. Some of them have 

 several hundred legs ; but do not, on that account, walk 

 faster than such as have only six. 



The wings, which are two or four in number, are 

 sometimes formed of a simple, and more or less trans- 

 parent, gauze, and sometimes covered with little scales, 

 differently figured ; in some they are composed of fea- 

 E 3 



