THE HEAD OF THE BEE AND ITS APPENDAGES. 



27 



are rounded and capped by the large compound eyes {E). In the 

 opposite direction the head is very much flattened, the greatest diame- 

 ter being crosswise through the middle of the eyes. The face is con- 

 vex, while the posterior surface is somewhat hollowed out and fits 

 snugly upon the anterior end of the thorax. 



The large lateral eyes (fig. 9 A, E) are called the compound eyes, 

 because each is composed of a large number of separate eye elements 

 forming the little hexagonal facets visible on the surface. All of 

 these facets together constitute the cornea^ or the transparent outer 

 surface of the eye, which in the bee is densely clothed with long hairs. 

 The dark color of the eye is located in the deeper parts, but these w^ill 

 be described in the section dealing with the nervous system. On the 



Vx Q 



Vx ten 



PrbFs 



Gls'l^ Pgl 



Fig. 9. — A, front view of head of worker bee with mouth parts (Prl)) cut off a short 

 distance from their bases ; B, corresponding view of posterior surface of head. 



top of the head between the compound eyes are the three simple eyes, 

 or ocelli {0), arranged in a triangle with the median ocellus in front. 



Between the lower halves of the large eyes and near the center of the 

 face arise the antennae {Ant)^ each of wdiich is inserted into a small, 

 circular, membranous socket of the head wall, and consists of a long, 

 basal, 1-segmented stalk carrying a terminal 11-jointed arm movably 

 articulated to the stalk and generally hanging downward from it. 

 (In the drone the terminal arm consists of 12 joints.) 



The mouth parts are attached at the lower part of the head, and 

 consist of the mandibles (Md) laterally and the maxilhe (Mx) 

 and lahium (Lb) mesially. The latter two include the set of elongate 

 bladelike organs surrounding the protrusible " tongue," which to- 

 gether constitute what is connnonly known as the proboscis {Prb). 



