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 the antennae 
represent the ears, and that although they may not 
directly convey the vibrations of sound to 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 which 
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. 
