Olfactory Organs of Insects 87 



excites those previously established in its 

 nervous substance. 



In order to substantiate the fact that the 

 organs of smell are located on the antennae of 

 flies and other insects, we may refer to one 

 among the numerous experiments which Mon- 

 sieur Forel has made. He placed the body of 

 a decomposing mole under a hemispherical 

 wire gauze cover. A fly soon arrived and tried 

 to gain access to the dead animal. Forel caught 

 the fly, and after destroying its eyes let it go. 

 The insect flew about the room knocking itself 

 against the ceiling and walls, and finished by 

 falling on the floor in a helpless state. Forel 

 then removed one of the fly's wings, and after- 

 wards placed it near the mole, which he un- 

 covered ; the fly immediately set to work to feed 

 on the dead animal. He then removed the 

 insect's antennae ; from that moment, despite 

 oft-repeated trials, the fly paid no more atten- 

 tion to the mole than to a piece of stone or a 

 bit of wood. 



Taste. Insects as a rule possess the power 

 of distinguishing between the quality of certain 

 non-volatile substances before swallowing them. 



