THE ABDOMEN, WAX GLANDS, AND STING. 



69 



worker, but the drone's claws (C) are large and very strikingly 

 different in shape from those of either the worker or the queen. 



The empodium (fig. 30 A, B, and C,_£m£) consists of a terminal 

 lobe bent upward between the^cla^S- (C) and deeply cleft on its 

 dorsal surface (A) , and of a thick basal stalk 

 whose walls contain a number of chitinous 

 plates. One pi these plates is dorsal (A and 

 C, hh) and bears five very long, thick, curved 

 hairs projecting posteriorly over the terminal 

 lobe, while a ventral plate (B and C, ii) is 

 provided with numerous short thick spines. 

 A third plate (A, B, and C, ffg) almost 

 encircles the front of the terminal lobe, its 

 upper ends reaching to the lips of the cleft. 



When the bee walks on any ordinary sur- 

 face it uses only its claws for maintaining a 

 foothold, but when it finds itself on a smooth, 

 slippery surface like glass the claws are of no 

 avail and the empodia are provided for such 

 emergencies as this. The terminal lobe is 

 pressed down against the smooth surface and 

 its lateral halves are flattened out and adhere 

 by a sticky liquid excreted upon them by 

 glands said to be situated in front of them, 

 the muscle that flattens the empodial lobes the latter spring back 

 into their original position by the elasticity :of the chitinous band 

 (gg) in their walls. 



C ' 



Pig. 31. — A, outer view of 

 hind claw of worker ; B. 

 same of queen ; C, same 

 of drone. 



On the relaxation of 



V. THE ABDOMEN, WAX GLANDS, A^D STING. 



The abdomen of the worker and queen appears to consist of six seg- 

 ments (figs. 1, 32, 33, II-VII), but it must be remembered that, as 

 has already been explained, the thoracic division of the body in the 

 Hymenoptera includes one segment, the propodeum or median seg- 

 ment, which really belongs to the abdomen and is its true first seg- 

 ment according to the arrangement in all other insects. Hence, 

 counting the propodeum (figs. 21 and 32, IT) as the first, we find 

 seven exposed abdominal segments in the worker and queen and 

 nine in the drone. Each one except the first consists of a tergum 

 (T) and a sternum (S), the former reaching far down on the side 

 of the segment, where it carries the spiracle (Sp) and overlaps the 

 edge of the sternum. The two plates of the last or seventh segment 

 in the worker and queen are separated by a cleft on each side, and 

 if they are spread . apart it is seen that the tip of the abdomen 



