30 



BRITISH BEES. 



the gullet and assists deglutition ; the labium, or lower 

 lip, and the true tongue. These parts are all single ; 

 the parts in pairs are the mandibles, the maxillae, the 

 maxillary palpi, the labial palpi, and the paraglossce. 

 The labrum, or upper lip, is attached by joint to the 



apex of the cly- 

 peus; it has a ver- 

 tical motion, and 

 falls over the or- 

 1.7 gans beneath it, 

 in repose, when it 

 is itself covered 

 bv the mandibles. 



* 



It is usually trans- 

 verse in form, but 



Fig. 7. Troplii and their unfolding, a, labrum ; . 



6, epipharynx ; c, pharynx ; d, hypopharynx ; e, man- IS Sometimes 

 dible;/, maxillae; g, maxillary palpi ; A, mandible; j- nil i nr 



i, cardium; k, labium ; I, labial palpi ; m, paraglossse ; P e lr > 



n, tongue. cially in the ar- 



tisan bees. It takes many forms, sometimes semilunar 

 or linear, emarginate or entire, convex, concave, or flat, 

 and is occasionally armed with one or two processes, 

 like minute teeth projecting from its surface, but of what 

 use these may be we do not know. In the female of 

 Halictus, it has a slightly longitudinal appendage in the 

 centre. It is usually horny, but is sometimes coriaceous 

 or leathery. This labrum often yields good specific cha- 

 racters. 



The pharynx, or gullet, is a cavity immediately be- 

 neath the epipharynx, which articulates directly under 

 the base of the labrum, and which closes the pharynx 

 from above, and immediately beneath this cavity is 

 another small appendage, almost triangular, which re- 

 ceives the food or honey from the canal conveying it 



