46 
BRITISH BEES. 
small tubercle, or boss, separated from the surround¬ 
ing integument by a suture, the colouring of which fre¬ 
quently yields a specific character, but its uses are not 
known. 
The metathorax carries the posterior legs laterally 
beneath, and in the centre, behind, the abdomen. The 
posterior legs are the chief organs 
used by the majority of bees for the 
conveyance of pollen to store in 
their cells, or, as in the case of 
humble-bees or the hive bee, the 
bee bread for the food for the young, 
or the requisite materials, in the ma¬ 
jority of other bees, for nidification. 
To this end they are either densely 
clothed with hair throughout their 
whole extent, — usually externally 
only,—or this is limited to the ex¬ 
ternal surface of the posterior shank. 
In the social bees this shank is edged 
externally with stiff bristles. In 
these, as in most of the bees, this 
limb greatly and gradually expands 
towards its articulation with the 
planta , or first joint of the tarsus; and this surface, 
which is perfectly smooth, serves to the social bee as 
a sort of basket to hold and convey the collected 
materials. The first joint of the tarsus, or planta, of 
this leg is also used in the domestic economy of the in¬ 
sect to assist in the same object. In the domestic bee the 
under side of the posterior plantse have a very peculiar 
structure, consisting of a series of ten transverse broad 
parallel lines of minute dense but short brushes, which 
Fisr.13.—Posterior legs: 
1, of abnormal bee (An- 
drena) ; 2, scopuliped 
normal bee ( Eucera ); 3, 
parasitic bee ( Nomada ). 
a, coxa ; b, trochanter, 
with flocculus; c, femur; 
d, tibia; e, planta ; f, spi- 
nulae; g, tarsus, with its 
claws. 
