426 EXTERNAL ANATOMY OF INSECTS. 



restrained, at least in some, to two directions, towards 

 and from the mouth. They were called palpi or feelers, 

 because the insect has been supposed to use them in ex- 

 ploring substances. There seem to be no organs in the 

 vertebrate animals directly analogous to thepalpi of in- 

 sects and Crustacea, unless, perhaps, the cirri that emerge 

 from the lips of some fishes, as the cod, red mullet, &c. 

 which Linne defines as used in exploring (prcetentantes). 

 Whether the vibrissas, miscalled smellers, of some quadru- 

 peds and birds have any reference to them, I will not 

 venture to affirm ; but the feline tribe evidently use their 

 bristles as explorers, and they are planted chiefly in the 

 vicinity of the mouth. 



Having made these general remarks, I shall now con- 

 fine myself to the labial palpi. I call them labial palpi, 

 because that term is in general use, and because in many 

 cases they really do emerge from what I consider as the 

 labium, as in most of the chafers; but they might with 

 equal propriety be denominated lingual palpi, since they 

 sometimes appear to emerge from the tongue (as in the 

 stag-beetle {Lucaniis Cervus). In some instances, as in 

 the Predaceous beetles, they seem to be common to both 

 labium and tongue, being attached at their base on the 

 upper side to the former, and on the under side to the 

 latter. As to their situation : they emerge from the base 

 of the labium in the locusts [Locusta Leach) a ; from its 

 middle in Hister maximus h \ from its summit in Amblyte- 

 rus MacLeay c ; and from its lateral margin in Di/nas- 

 tes MacLeay, &c. They consist of from one to Jour 



a Plate VI. Fig. 6. b". b Hor. Entomolog, 1. 1. \.f. l.g. 



c Ibid.t.ilf. 18. g. 



