PHYLUM ARTHROPODA 



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

 pharynx (Fig. 237, g), a pair of mandibles (w), two maxilla? (w.v), 

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

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

 projects the fleshy c pi- 

 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 mentum, 

 beyond which is the ligula. 



FIG. 237. Head of worker honey-bee. 

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

 m. mandible; mx, maxilla; mxp, maxillary 

 palpus; /, hypopharynx; Ip, labial palpus. 

 (From Packard, after Cheshire.) 



or tongue (I), with one 



labial palpus (Ip) on each 



side. The ligula may be 



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 maxillae (Fig. 237, 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. 



