ORGANS OF THE SENSES. 



35 



the thorax, immediately above the insertion of the 

 third pair of legs. They consist of a solid ring, within 

 which is stretched a fine membrane, forming a regular 

 drum. This is visible externally ; on its inner surface 

 the membrane bears certain horny processes, of which 

 one exhibits numerous honeycomb-like cells. The 

 acoustic nerve is given off from the third ganglion of 

 the thorax; it terminates in an oval knob, which is 

 applied against the honeycombed process, and gives 

 off from its extremity numerous minute filaments 

 which lodge in the horny cells. 



It is probable that most insects possess a sense of 

 taste in a greater or less degree, but in many of them 

 the so-called tongue is horny in its texture; the 

 sense of smell would also appear to belong to them, 

 but no olfactory organ has yet been indicated in 

 them. The last sense, the universal sense of touch, 

 is of course possessed by them in common with all 

 other animals, and the palpi are certainly to be re- 

 garded as special organs of touch. 



I have thus as succinctly as possible brought to- 

 gether the leading particulars of the organization of 

 the Insect world, not only to show the principal points 

 of structure in which the majority of these creatures 

 agree, but also to give the reader an idea of some 

 of the many wonderful facts revealed to us by their 

 anatomy. I have done my best to render these 

 details interesting ; how far I have succeeded I must 

 leave the reader to judge; and if he cannot regard 

 this chapter in any other light than as a veritable 

 slough of despond, the best thing we can do is to 

 be thankful we have got safely through it. 



