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 antennz ; this is present in all three forms, and 
varies with the size of the antenne. 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 
