334 PHYLUM ARTHROPODA. 



in which the nectar is superficial. The hive-bees and humble-bees, on 

 the other hand, are specially modified to enable them to extract nectar 

 from tubular flowers. When not in use, the elongated mouth-parts are 

 folded back upon themselves, not coiled as in butterflies and moths, 

 where there is even greater elongation. 



In the queen and in the drone the mouth-parts are shorter, and are 

 not used in honey-gathering. 



The thoracic appendages consist as usual of three pairs of legs, which 

 have the usual parts. On the first leg, at the junction of the tibia and 

 the first tarsal joint, there is a complicated mechanism which is em- 

 ployed in cleaning the antennae ; this is present in all three forms, and 

 varies with the size of the antennae. In the workers the third leg is 

 remarkably modified for pollen-gathering purposes. The first tarsal 

 joint bears regular rows of stiff straight hairs on which the pollen grains 

 are collected ; they are borne to the hive in the pollen basket, placed 

 at the back of the tibia, and furnished with numerous hairs. In queen 

 and drone these special arrangements of hairs are absent. 



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 employed 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 segment, 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. Ramify- 

 ing through the abdomen are found the two slender coiled tubes which 

 constitute 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. 



Nervous system. In the adult this exhibits considerable 



