NO. 2 



HONEY BEE SNODGRASS 



29 



hypopharynx, but the structure as developed in the bee (B) is char- 

 acteristic of the Hymenoptera. 



In the honey bee the food glands that furnish the so-called royal 

 jelly open by pores on the distal angles of the oral plate (fig. 10 B, 0). 

 It may be noted incidentally, therefore, that these glands are hypo- 

 pharyngeal glands and not "pharyngeal" glands as they are generally 



LbPl 



Gls 



Fig. 9. — The preoral food channel and the mouth region in Apis and Vespula. 



A, base of protracted proboscis of worker bee, anterior view, exposing the 

 epipharynx, mouth, bib, and food channel between lacinial lobes of maxillae. 

 B, same, base of proboscis retracted, food channel closed by lacinial lobes pressed 

 against epipharynx. C, cross section through distal part of proboscis. D, 

 mouth region of Vespula macidata (L.), anterior wall of sucking pump removed, 

 showing oral plate (opl), suboral bib (bib), and closed entrance to infrabuccal 

 sac (IbS). E, same in natural condition, ventral view, mouth closed to a 

 narrow slit (Mth) above closed entrance to infrabuccal sac (IbS), overhung 

 by labrum (Lm). 



c, anterior articulation of mandible; s, suspensorial rod of hypopharynx; 

 x, mandibular branch of s; y, pharyngeal arm of oral plate. 



termed. Their secretion discharged upon the hypopharyngeal bib 

 evidently accumulates in the food channel on the base of the proboscis, 

 where it becomes accessible to other adult bees. The open food 

 channel thus serves as a feeding trough for the queen and the drones 

 when the latter are being fed by the workers. The muscles attached 

 on the pharyngeal arms of the oral plate would appear to give move- 

 ments to the oral plate and the bib that might facilitate the expulsion 

 of the royal jelly into the feeding trough, but the plate with its arms 



