COLEOPTEROUS INSECTS. 105 



a function analogous to that of touch, being em- 

 ployed in exploring the depth of crevices, and in 

 ascertaining by contact the nature of any opposing 

 object. But as their extreme shortness in two- 

 winged flies (Diptera), and some other insects, does 

 not accord with that usage, they are likewise sup- 

 posed to be the seat of a particular sense. Proceed- 

 ing on the assumption that all the organs of sensa- 

 tion found in the higher animals have their analogues 

 in insects, some observers maintain that d-e antennae 

 represent the ears, and that although tlit?y may not 

 directly convey the vibrations of sound tt> the sen- 

 sorium, their primary function is something related 

 to hearing. Others again suppose that they are the 

 media through which the sense of smell is effected, 

 but this explanation of their use is disproved by 

 Huber's observations on Bees, which show that the 

 sense of smell, at least in these hymenopterous spe- 

 cies, is placed within the cavity of the mouth. 



The appendages of the head and mouth wJVeh 

 have just been described, are represented in their 

 natural position by the following figures, which we 

 have taken the liberty to copy from Griffith's edition 

 of Cuvier's Animal Kingdom: a (fig. 1) is the la- 

 brum or upper lip ; b the mandibles ; c the exter- 

 nal maxillary palpi ; d the labial palpi ; e the an- 

 tennae ; f (fig. 2) the labium or under lip ; g the 

 mentum, with a triangular tooth in the centre of its 

 notch ; h the internal maxillary palpi ; i the max- 

 illae, produced into an acute arcuate lobe. 



