180 ANATOMY AND PHYSIOLOGY 



Swammerdam and Cuvier the recurrent nerve. The 

 double nervous web preponderates in the Orthoptera, 

 and especially in Locusta and Gryllus. 



The remarkable and characteristic attribute of this 

 system is, that it is in no degree influenced by the 

 changes which the ventral system undergoes in the 

 different stages of metamorphosis. It is quite as 

 fully developed in the young larva as in the perfect 

 insect and vice versa. It may be thence naturally 

 inferred that its functional uses are required at the 

 earliest stage of life ; and this in reality is the case, 

 for it is destined to preside over the functions of 

 what has been called vegetative life, which reach 

 their highest pitch of activity in larvsB. 



As the nerves constitute the fundamental organs 

 of all sensation, this is the proper place to speak of 

 the senses, the avenues through which the properties 

 of external objects are conveyed to them. Judging 

 partly from their structure, and partly from the 

 actions that follow certain impressions received from 

 without, we are inevitably led to infer, that insects 

 possess at least all the senses which exist in the higher 

 animals, some of them even in a greater state of per- 

 fection. Nay, it is by no means improbable that 

 additional ones have been assigned them, to which 

 we have nothing analogous in our own system, anc 

 of which, therefore, we cannot form any accurate 

 conception. It is even a matter of doubt what 

 organs are to be regarded as the seat of certain senses 

 the existence of which we are scarcely authorised to 

 call in question. 



