436 HABITATIONS OF INSECTS. 



built by the parent insect, not for its own use, but for the 

 convenience of its future young ; and those which are 

 formed by the insect that inhabits them for its own accom- 

 modation. To the first I shall now call your attention. 



The solitary insects which construct habitations for 

 their future young without any view to their own accom- 

 modation, chiefly belong to the order Hymenoptwa, and 

 are principally different species of wild bees. Of these 

 the most simple are built by M. succincta, fodiens, and 

 other species of the first family of the genus Melitta, 

 Kirby (Colletes, Latr.). The situation which the parent 

 bee chooses, is either the dry earth of a bank, or the 

 vacuities of stone walls cemented with earth instead of 

 mortar. Having excavated a cylinder about two inches 

 in depth, running usually in a horizontal direction, the 

 bee occupies it with three or four cells about half an inch 

 long, and one-sixth broad, shaped like a thimble, the end 

 of one fitting into the mouth of another. The substance 

 of which these cells are formed is two or three layers of 

 a silky membrane, composed of a kind of glue secreted 

 by the animal, resembling gold-beater's leaf, but much 

 finer, and so thin and transparent that the colour of an 

 included object may be seen through them. As soon as 

 one cell is completed, the bee deposits an egg within, and 

 nearly fills it with a paste composed of pollen and honey; 

 which having done, she proceeds to form another cell, 

 storing it in like manner until the whole is finished, when 

 she carefully stops up the mouth of the orifice with earth. 

 Our countryman Grew seems to have found a series of 

 these nests in a singular situation — the middle of the 



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