28 THE HOME OF THE BEES. 



separately. The female bee, having deposited a small pellet of 

 mud in a sheltered spot between some tufts of grass, immedi- 

 ately begins to excavate a small cavity in its upper surface, 

 scraping the mud away from the centre towards the margin by 

 means of her jaws. A small, shallow mud-cup is thus produced. 

 It is rough and uneven on the outer surface, but beautifully 

 smooth on the inner. On witnessing thus much of the work 

 performed, I was struck with thi-ee points : first, the rapidity 

 with which the insect worked; secondly, the tenacity with 

 which she kept her original position whilst excavating; and 

 thirdly, her constantly going over woi'k Avliich had apparently 

 been completed. . . . The lid is excavated and rendered concave 

 on its outer or upper surface, and is convex and rough on its 

 inner surfsice ; and, in fact, is a simple repetition of the first- 

 formed portion of the cell, a part of a hollow sphere." 



The largest species of Osmia known to us is a very dark-blue 

 species (O. lignivora). We are indebted to a lady for speci- 

 mens of the bees with their cells, which had been excavated in 

 the interior of a maple tree several inches from the bark. The 

 bee had industriously tunnelled out this elaborate burrow (Fig. 

 26), and, in this respect, resembled the habits of the Carpenter 

 bee more closely than any other species of its genus. 



The tunnel was over three inches long, and about three-tenths 

 of an inch wide. It contracted a little in w^idth between the 

 cell, showing that the bee worked intelligently, and wasted no 

 more of her energies than was absolutely necessary. The bur- 

 row contained five cells, each half an inch long, being rather 

 short and broad, with the hinder end rounded, while the oppo- 

 site end, next to the one adjoining, is cut oft" squarely. The cell 

 is somewhat jug-shaped, owing to a slight constriction just 

 behind the mouth. The material of which the cell is composed 

 is stout, silken, parchment-like, and very smooth within. The 

 interstices between the cells are filled in with rather coarse 

 chippings made by the bee, 



' The bee cut its way out of the cells in March, and lived for a 

 month afterwards on a diet of honey and water. It eagerly 

 lapped up the drops of water supplied by its keeper, to whom it 

 soon grew accustomed, and seemed to recognize. 



Our smallest and most abundant species is the little green 

 Osmia simillima. It builds its little oval, somewhat urn-shaped 

 cells against the roof of the large deserted galls of the oak-gall 



