SLIME SLUGS, MYRIAPODS AND INSECTS 129 



hairy rod is forced up the tube by the pressing together of the 



parts composing its walls. 

 Antennae and Senses. The two feelers, or antennae, of the 



bee are slender, elbowed processes, each composed of thirteen 



small segments, which can be moved freely, and extend out in 



front of the face so as to be in advance of the head when the 



bee is flying or walking. They are general 



organs of touch and smell and probably 



also of hearing. Each of these senses 



has its own particular specific organs on 



the antennae, those of feeling being fine 



tactile hairs and papillae, those of smell 



being variously shaped very minute pits 



or cones, each with a fine nerve ending 



in it, while those of hearing are more 



problematical. But it has been proved 



that many insects have special auditory 



organs in the antennae consisting usually 



of fine hairs which can be set into vib- 



ration by the sound waves, and an elabo- 



rate receiving arrangement, in the second F _ M , 



segment, of chitin rods, delicate nerve parts of a honey-bee 



fibers, special ganglion cells and an audi- with maxilla and man- 



tory nerve running to the brain. The .*& - 



male mosquito has a very highly deve- ble-mx., maxilla; mx.p., 



loped auditory apparatus of this type. maxillary palpus; mx.L, 

 Af . , ,, i maxillary lobe; st., 



A few insects, such as the grasshopper, stipes of max jn a; 



katydids, crickets and others have a 



cardo of 



very different kind of "ear," not situated ! abium ; 

 ' turn of 



maxilla; II., 

 w., submen- 

 labium; m., 

 mentum of labium; pg., 



,,,., 



on the head, but on the abdomen (in 



the grasshoppers), front legs (in katydids paraglossa. gl., glossa; 

 and crickets), or elsewhere on the body. Kp '' labia palpus ' 

 This kind of ear is composed of a small, thin vibratory drum 

 or tympanum, with an air-space underneath it, and a tiny 

 ganglion and special nerve in connection with it. 



The sense of smell is very highly developed in most insects. 

 Indeed it is probable that most of an insect's sensation of out- 

 side things comes through its organs of smell. And the 



