296 PERIPATVS, MYRIOPODS, AND INSECTS. 



The second and third thoracic segments bear each a pair of wings. 

 These are largest in the drones and relatively smallest in the queen, 

 who flies but seldom. At the base of each wing there is a respiratory 

 spiracle. 



In the adult queen and worker, the abdomen is divided into six 

 segments ; in the drone, into seven. There are no abdominal appen- 

 dages. On the ventral surface in the worker, but not in the queen or 



drone, there are four pairs of 

 wax pockets or glands, which 

 secrete the wax, which, after 

 mastication with saliva, is em- 

 ployed in building the combs. 

 The abdomen also bears in 

 queen and worker five pairs of 

 spiracles, but in the drone, on 

 account of the additional seg- 

 ment, there are six pairs. The 

 total number of spiracles is thus 

 fourteen for queen and worker, 

 and sixteen for the drone. The 

 posterior region of the abdomen 

 bears the complicated sting. In 

 the worker this consists of a 

 hard incomplete sheath, which 

 envelops two barbed darts. The 

 poison flows down a channel 

 lying between the darts and the 

 sheath. Ramifying through the 

 abdomen are found the two 

 slender coiled tubes which con- 

 stitute the poison gland. At the 

 posterior end of the body these 

 unite and open into a large poison 

 sac. When a bee uses its sting, 

 the chitinous sheath first pierces 

 the skin, and then the wound 

 is deepened by the barbed and 

 pointed darts, while at the same 

 time poison is steadily pumped 

 down the channel mentioned 

 above, and pours out by minute 

 openings at the bases of the darts. 

 The poison contains formic acid, 

 and is fatal to the bee if directly introduced into its blood. Associated 

 with the sting there are a pair of delicate tactile palps. In the queen the 

 sting is curved and more powerful, but it is apparently only used in 

 combat with a rival. In the worker the sting, and with it a portion of 

 the gut, is usually lost after use, and, in consequence, death ensues ; the 

 queen, on the other hand, can withdraw her sting from the wound with 

 considerable ease. The sting is really an ovipositor adapted to a new 

 function. Naturally, therefore, there is no trace of it in the drones. 



Fig. 130. — Head and mouth-parts of 

 bee. — After Cheshire. 



a., Antenna; ;«., mandible ; £-., labrumor 

 epipharynx ; inx.p., rudiment of maxil- 

 lary palp ; mx., lamina of maxilla ; /p., 

 labial palp; /., ligula ; b., bouton at 

 end. The paraglossee lie concealed 

 between the basal portions of the labial 

 palps and the ligula. 



