THE APPENDAGES OF THE HEAD. 



with the soft membrane of the mouth. In the Bees, it is enor- 

 mously developed and covered with soft hairs. It is often 

 confounded with the palpiger. In Hydrous it is divided into 

 two lobes. In most of the Carabidce and Bees it is divided 

 into three lobes, the two outer ones forming the pciraglosfOi- 

 (Fig. 41m), and acting as feelers, while the middle, usually 

 much longer, forms the lingua, oc tongue, being the continuation 

 of the ligula. In the bees, where 

 the ligula is greatly developed, 

 it performs the part of the tongue 

 in Vertebrates, and aids the max- 

 illae in collecting nectar and 

 pollen. 



The roof of the mouth is 

 formed by the labrum and the 

 epipharynx (Fig. 42 c), a small 

 fleshy tubercle concealed beneath 

 the labrum. It is seen in the 

 bees on turning up the labrum. 

 It probably corresponds to the 

 "labellum" of Schiodte. The 

 labrum (Fig. 41 e) is usually 

 transverse and situated in front 

 of the clypeus (Fig. 41&). The 

 shield-like clypeus is the broad, 

 visor-like, square piece forming usually the front of the head. 

 Behind it is the clypeus posterior, or supra-dypeus, a subdivision 

 of the clypeus, and especially observable in the Ilyrnenoptera. 

 The epicranium forms a large part of the head ; it is bounded 

 posteriorly by the occiput, on the sides by the eyes, and in 

 front by the clypeus, and though usually described as a 

 single piece, is really composed of several. The ocelli often 

 appear to be situated upon it, though in reality they are placed 

 upon a distinct piece or pieces. The "epicranial suture" is the 

 line of junction of the two " procephalic lobes" (Huxley). 



FIG. 41. Front view of the head of a bee, Anthcphora. a, compound eyes; c, 

 three simple eyes, situated upon the epicranium; b, clypeus; c, labrum; d, an- 

 tenna;/, mandibles; i, maxilhc; h, maxillary palpi; I, palpifer; j, labial palpi; m, 

 paraglossae; k, ligula. From Newport. 



3* 



