ANATOMY AND PHYSIOLOGY 



99 



tine, acetic acid and other pungent fluids, no longer re- 

 spond to the same stimuli after their antennae have been 

 amputated or else covered with paraffine to exclude the 

 air.' His experiments were conducted under conditions 

 such that the results could not be ascribed to the shock 



FIG. 130. 



sc 



Taste cup from maxilla 

 of Bombus. sc, sensory 

 cell; n, nerve. After WILL. 



nv 



Section of antennal olfac- 

 tory organ of grasshopper, 

 Caloptenus. c, cuticula; m, 

 membrane; n, nucleus of 

 sensory cell; nv, nerve; p, 

 pit with olfactory peg; pg, 

 pigment. After HAUSER. 



of the operation or to effects upon the gustatory or res- 

 piratory systems; except for having lost the sense of smell, 

 the insects experimented upon behaved in a normal manner. It 

 should be said, however, that Carabus, Melolontha and Silpha 

 still reacted to some extent toward strong vapors even after the 

 extirpation of the antennae ; while in Hemiptera the loss of the 

 antennae did not lessen the response to the odors used. These 

 facts indicate that the sense of smell is not always confined to 

 the antennae; indeed the maxillary palpi are frequently olfac- 

 tory, as in Silpha and Hydaticus; also the cerci, as in the cock- 

 roach and other Orthoptera. Experiments indicate that an 



