ANATOMY OF INSECTS INTERNAL 



Touch. The sense of touch is very highly developed in many 

 insects, sensory tactile hairs commonly occurring over the whole 

 body, and the antennae, palpi, and 

 cerci being specially developed as 

 tactile organs. 



Taste. Both observation and 

 experiment have shown that in- 

 sects have a well-developed sense 

 of taste, though it is often quite 

 different from that of man, as 

 they detect some substances but 

 fail to perceive others, and often 

 seem to relish substances wholly 

 repugnant to us. The sense of 

 taste is located in sensory hairs or microscopic pegs borne upon 

 the tongue (see Fig. 47), or hypopharynx, on the epipharynx (a 



FIG. 47. Tip of tongue of honey-bee 



Showing labellum (Ldt), guard hairs (ffr), 



and ventral groove (), from above and 



below. (After Snodgrass, United States 



Department of Agriculture) 



FlG. 48. Nerve endings in tip of maxillary palpus of (a) Locusta viridisstma, 

 and in labial palpus of (b) Machilis polypoda. (Greatly magnified) 



s/i, sense hairs ; sc, sense cells ; be, blood cells. (After Vom Rath, from Kellogg) 



sensory portion of the roof of the pharynx similar to the palate of 

 higher animals), and on the maxillary and labial palpi. Probably the 

 sense of smell is used more than the sense of taste in choosing food. 



