PHYLUM ARTHROPOD A 



The mouth parts consist of a labrum, or upper lip, the epi- 

 pharynx (Fig. 237, g), a pair of mandibles (m), two maxillae (mx), 

 and a labium, or under lip (/, lp.). The labrum is joined to the 

 clypeus, which lies just above it. From beneath the labrum 



projects the fleshy epi- > . 



pharynx (g); this is prob- : '^, 



ably an organ of taste. 

 The mandibles, or jaws (m), 

 are situated one on either 

 side of the labrum; they 

 are notched in the queen 

 and drone, but smooth in 

 the worker. The latter 

 makes use of them in 

 building honeycomb. The 

 labium is a complicated 

 median structure extend- 

 ing downward from be- 

 neath the labrum. It is 

 joined to the back of the 

 head by a triangular piece, 

 the' submentum. Next to 

 this is a chitinous, muscle- 

 filled piece, the menhim, 

 beyond which is the ligula, 

 or tongue (7), with one 

 labial palpus (lp) on each 



FIG. 237. Head of worker honey-bee. 



a, antenna ; b, bouton ; g, epipharynx ; 

 m, mandible; mx, maxilla; mxp, maxillary 

 palpus; /, hypopharynx; lp, labial palpus. 

 Side. The ligula may be (From Packard, after Cheshire.) 



drawn in or extended. It 



is long and flexible, with a spoon or bouton (b) at the end. Hairs 

 of various kinds are arranged upon it in regular rows; these are 

 used for gathering nectar, and as organs of touch and taste. 

 The maxillce (Fig. 2T,'j,mx), or lower jaws, fit over the mentum 

 on either side. Along their front edges are rows of stiff hairs. 

 Maxillary palpi (mxp) are also present. 



