326 



ZOOLOGY. 



sound, heard and appreciated by individuals of the other 

 sex. Any insect which produces a sound must be supposed to 



have ears to hear the sound pro. 

 duced by others of its species. 

 In the antennas, palpi, and 

 abdominal appendages of dif- 

 ferent insects are seated mi- 

 nute olfactory organs consisting 



Fi?. 285 A, b, sense-organ on the ab- j> -A i /-nv cmr\ 



dominal appendages of a Ay(Chrygopila)- OI PltS alone (X Ig. ^85), Or ot 



omna appenages o a yrygopa): . , 



c, sent-e-organ on the terminal joint of V.,,4, -. i J.T. j ^ 



palpus of Arte. Author d,t. hairs perforated at the end, and 



pegs associated with the pits. 



The ears (or auditory sacs) of the locust are situated, one 

 on each side, on the basal joint of the abdomen, just be- 



si 



from the 



. After Graber. 



hind the first abdominal spiracle (Fig. 274). The ap- 

 paratus consists of a tense membrane, the tympanum, sur 

 rounded by a horny ring (Fig 286). " On the internal sur- 



