There is a family of wild bees which carry on the trade of masons, building their solid houses solely of artificial stone. The first step of the mother bee, Apis mururia, Oliv. (Anthophara, F. Me-gachile, Latr.) is to fix upon a proper situation for the future mansion of her offspring. For this she usually selects an angle, sheltered by any projection, on the south side of a stone wall. Her next care is to provide materials for the structure. The chief of these is sand, which she carefully selects, grain by grain, from such as contain some mixture of earth; these grains she glues together with her viscid saliva into masses the size of small shot,* and transports by means of her jaws to the site of her castle. With a number of these masses, which are the artificial stone of which her building is to be composed, united by a cement preferable to ours, she first forms the basis or foundation of the whole. Next she raises the walls of a cell, which is an inch long and half an inch broad, and, before its orifice is closed, in form resembles a thimble. This, after depositing an egg, and a supply of honey ana pollen, she covers in, and then proceeds to the erection of a second, which she finishes in the same manner, until the whole number, which varies from four to eight, is completed. The vacuities between the cells, which are not placed in any regular order, some being parallel to the wall, others being perpendicular to it, and others inclined to it at different angles, this laborious architect fills up with the same material of which the cells are composed, and then bestows upon the whole group a common covering of coarser grains of sand. The form of the whole nest, which, when finished, is a solid mass of stone, so hard as not to be easily penetrated with the blade of a knife, is an irregular oblong, of the same colour as the sand, and, to a casual observer, more resembling a splash of mud than an artificial structure. These bees sometimes are more economical of their labour, and repair old nests, for the possession of which they have very desperate combats. One would have supposed that the inhabitants of a castle so fortified might defy the attack of an insect marauder. Yet an ichneumon, and a beetle (Clerius apiarius, F.) both contrive to introduce their eggs into the cells, and the larvae proceeding from them devour their inhabitants. - Reaum. vi. 57, 58 Mon. Ap. Angl. i. 179.

* Reaumur plausibly supposes, that it has been from observing this bee thus loaded, that the talc mentioned by Aristotle and Pliny, of the hive-bee's ballasting itself with a bit of stone, previous to flying home in a high wind, has arisen.

Other bees of the same family use different materials in the construction of their nests. Some employ fine earth made into a kind of mortar made with gluten. Another, (A. caerulescens, L.) as we learn from De Geer, forms its nest of argillaceous earth, mixed with chalk, upon stone walls, and sometimes probably builds in chalk-pits. Apis bicornis, L. selects the hollows of large stones for the site of its dwelling; whilst others prefer the holes in wood.