INSECTA. 275 



(318.) Whether taste exists in insects as a distinct sense may 

 admit of dispute ; the tongue, already described, seems but little 

 adapted to appreciate savours, and, seeing this, it is obvious that 

 all opinions assigning the function of tasting to other parts are 

 purely conjectural. 



(319.) Many insects are certainly capable of perceiving odours ; 

 of this we have continual proof in the flesh-fly and other species, 

 that are evidently guided to their food, or select the position in which 

 to deposit their eggs, by smell ; but where the olfactory apparatus 

 is lodged is still a matter of doubt. The antenna and the palpi 

 have each had the power of smelling assigned to them, but without 

 much plausibility. The respiratory stigmata have been pointed 

 out as performing the office of examining the air admitted for the 

 purpose of breathing ; yet other authors, with equal probability, 

 look upon the ultimate ramifications of the trachese as forming one 

 extensive nose. The interior of the mouth has been indicated by 

 Treviranus ; * while Kirby and Spence find in the Necrophori, and 

 other insects remarkable for acuteness of smell, an organ in close 

 connection with the mouth, to which they attribute the perception 

 of odoriferous particles : this is a cavity situated in the upper lip, 

 containing a pair of circular pulpy cushions covered by a membrane 

 transversely striated or gathered into delicate folds. 



(320.) We are scarcely better informed concerning the organs of 

 hearing, but that insects are capable of perceiving sounds is proved 

 by the fact of many tribes being capable of producing audible noises 

 by which they communicate. There seems, indeed, to be little 

 doubt that the auditory apparatus is in some way or other con- 

 nected with the antennae. Some have supposed that these slender 

 and jointed organs, supplied, as they are, with large nerves, are 

 themselves capable of appreciating sonorous vibrations. Bur- 

 meister j- thinks that, as in crabs and lobsters, it is at the base 

 of the antenna that the ear is situated, and observes that if we 

 examine the insertion of these appendages we shall detect there 

 a soft articulating membrane which lies exposed, and is rendered 

 tense by the movements of the antenna, this he looks upon 

 as representing the drum of the ear, and conceives that it is so 

 placed as to receive impressions of sound, increased by the vibratory 

 movements communicated to the antennas by the sonorous undula- 

 tions of the atmosphere. 



* Vermischte Schriften, vol. ii. t Op. cit. p. 296. 



T 2 



