Page:Jardine Naturalist's library Bees.djvu/41

 of air-vessels, pervading every part of the body, and serving the purpose of lungs. The rushing of the air through them against the wings, while in motion, is supposed to be the cause of the humming sound made by the Bees.

To the lower part of the trunk are attached three pair of. The anterior pair, which are most efficient instruments, serving to the insect the same purpose as the arms and hands to man, are the shortest, and the posterior pair the longest. In each of these limbs there are several articulations or joints, of which three are larger than the others, serving to connect the thigh, the leg or pallet, and the foot or tarsus; the others are situated chiefly in the tarsus. (Plate II. Fig. 2., a. the haunch, b. the thigh, c. the tibia or pallet, containing on the opposite side, as represented at Fig. 4 a., the basket or cavity; d, e. the foot.) In each of the hinder limbs, one of which is represented in Plate II. Fig. 2, there is an admirable provision made for enabling the Bee to carry to its hive an important part of its stores, and which neither the queen nor the male possess, being exempted from that labour, viz. a small triangular cavity of a spoon-like shape, the exterior of which is smooth and glossy, while its inner surface is lined with strong close-set hairs. This cavity forms a kind of basket, destined to receive the pollen of flowers, one of the ingredients composing the food of the young. It receives also the propolis, a viscous substance, by which the combs are attached to the roof and walls of the hive, and by which any openings are stopped that might admit vermin or the cold.