198 HOMES WITHOUT HANDS. 



Several species select localities even more remarkable, and 

 make their nests in the empty shells of snails. The common 

 banded snail is a favorite with these bees, and in the British Mu- 

 seum may be seen a whole series of such nests. The number 

 of cells necessarily varies with the size of the snail-shell and the 

 number of its whorls, but on the average four or five cells are 

 found in each snail-shell. The process of forming the cells is 

 very simple. First, the bee deposits a quantity of pollen and 

 honey, then she places an egg upon the pollen, and then she 

 makes a partition with vegetable fibres torn by her teeth and 

 kneaded firmly together. Lastly, the whole opening of the cell 

 is closed by a wall formed of clay, tiny bits of stick, and small 

 stones, and then the bee goes off in search of another shell. 

 These shells may often be found under hedges, in moss, hidden 

 by grass, and on examination the nests of bees will frequently 

 be seen in them. 



In the Museum there is a beautiful example of ingenuity on 

 the part of the builder. Instead of choosing the cell of the band- 

 ed snail, she has taken that of the great garden snail, and filled it 

 with her cells. Thus it is evident that the shell is too large for 

 the formation of a single cell, and the little architect has, with 

 the greatest ingenuity, evaded the difficulty by placing two cells 

 side by side. When, however, the smaller whorls of the shell 

 were filled, and the bee approached the opening of the shell, the 

 space was too great even for the two cells placed side by side. 

 This difiElculty was, however, overcome as readily as the former, 

 and instead of placing the cells perpendicularly, the bee laid them 

 horizontally, and thus filled up the space. 



When the Osmia burrows into wood, she sets to work in a 

 very deliberate manner. " A bee," writes Mr. F. Smith, " is ob- 

 served to alight on an. upright post, or other wood suitable for its 

 purposes. She commences the formation of her tunnel, not by ex- 

 cavating downward, as she would be incommoded with the dust 

 and rubbish which she removes; no, she works upward, and 

 so airoids such an inconvenience. When she has proceeded to 

 the length required, she proceeds in a horizontal direction to the 

 outside of the post, and then her operations are continued down- 

 ward. She excavates a cell near the bottom of the tube, a second 

 and a third, and so on to the required number. The larvae when 

 full fed have their heads turned upward. The bees which arrive 

 at their perfect condition, or rather those which are first anxious 



