48 
BRITISH BEES. 
bees, as in Dasypoda, Panuryus, Eucera,Anthophora, etc. 
etc., it is conveyed upon the posterior legs, we do not 
know; we can only surmise that it is either to save the 
insect, in the former case, the labour of constructing a 
larger cylinder for nidification, so to prevent the possi¬ 
bility of its being rubbed off from the external surface 
of the legs, did these carry it, in entering the burrow, 
it being protected from this abrasion by being placed 
beneath the venter. In such insects the abdomen is 
usually truncated at its origin, or even hollowed within 
its base, thus to meet the projection of the metathorax, 
enabling it to draw itself closely up together, making 
the abdomen and metathorax, as it were, cohere. A 
different form of abdomen occurs in those bees which 
carry the pollen on their posterior legs. It is then more 
or less elliptical or lanceolate, which form permits the 
legs to be drawn up towards the metathorax within the 
space that kind of form furnishes, which, by this diffe¬ 
rent but equivalent arrangement, meets the same object. 
The similarity of the adjustment of the abdomen to the 
metathorax to that of Megachile, etc. in Apis and Bom- 
bus, by which insects the provision is also carried on the 
posterior legs, results from the totally different economy 
and habitation of the social bees, to which this structure 
is necessary for many purposes. 
If we observe this same peculiarity of structure in the 
cuckoo, or parasitical bees, it is because we find resem¬ 
blances where there are alliances. Thus, the male 
artisan bees, although not assisting in the labour of 
constructing the apartments, have similarly dilated man¬ 
dibles to those of their females. So also, in the form 
of the abdomen, the Nomadce are like the Andreyice 
and Halicti, upon which they are chiefly parasitical. 
