158 Beekeeping 



The muscles for moving the legs are located inside the 

 joints and are inserted on the chitinous walls. 



The last tarsal joint on each leg carries a pair of bilobed 

 claws (Fig. 82, Cla), which differ among the three types of 

 bees. Those of the drone are bent more nearly at right, 

 angles than those in the workers and queens and those of 

 the queen are larger than the claws of the workers. Between 

 the claws is a lobe (empodium, Emp) used when the bee 

 walks on a smooth surface. On such a surface the claws 

 are useless and the sticky empodium is lowered and flat- 

 tened, providing a good foothold. 



The motion of the legs in walking is typical of all insects. 

 The legs move in two sets ; the fore and hind legs on one 

 side move in the same direction as the middle leg on the 

 opposite side, thus giving a triangle for support at all times. 

 In flight the legs hang freely and are forced somewhat 

 backward, except when they are being used as in the manipu- 

 lation of pollen (p. 123). 



PROTECTIVE APPARATUS 



Worker bees defend the colony by means of the sting, 

 situated usually in a cavity at the tip of the abdomen (Fig. 



76) but capable of marvelously rapid action when it is 

 protruded. As was stated earlier (p. 140), this sting cavity 

 is formed by the infolding of the eighth, ninth and tenth 

 segments of the abdomen. The sting is homologous with 

 the ovipositor of other insects (see Snodgrass, I.e. pp. 76- 



77) and is made up of parts considered by some embry- 

 ologists as comparable with the legs and mouth parts of 

 the more anterior segments of the bee. The sting of the 

 worker bee is straight while that of the queen is longer, 

 curved and less strongly barbed. 



The sting (Fig. 83) and its accessory apparatus form a 

 rather complex structure. The shaft consists of three parts, 

 a dorsal sheath (ShS) along which move two barbed lancets 

 (Let). The sheath is enlarged at the anterior end into a 



