Insects. 103 



Notes on the Habits of Osmia atricapilla. By George li. 

 Waterhouse, Ksq. 



I met with Osmia atricapilla for the first time at Darenth wood, 

 about two or three years back, and then only with one specimen, 

 which was a female. In the beginning of June, 1835, however, 1 

 found it in tolerable abundance, flying about a high bank by the river- 

 side, near Liverpool : at this time none but females were to be seen, 

 though I hunted diligently for the other sex. Having secured speci- 

 mens for my cabinet, I then endeavoured to trace others to their nests 

 in order both to ascertain their habits, and to discover the male, that 

 sex being unknown to me. 



It was not long before I observed a female dart into a tuft of dry 

 grass near me ; and upon separating this tuft very carefully, to my 

 great delight, I discovered her in the act of constructing a cell. On 

 being thus exposed she discontinued her work, but soon resumed it 

 again upon my keeping myself perfectly quiet. 



The situation in which this cell was placed, as well as several other 

 cells which I afterwards found, was in a projecting part of the nearly 

 perpendicular bank, where the soil was of a light nature. Most of 

 the cells were deposited at the roots of dry grass, the lower part of 

 each cell being generally inserted in the soil, and the upper part ex- 

 posed. In a perfect nest the cells were never detached, but always 

 two or three, and sometimes five or six, were joined side by side. In 

 some instances I have found the cells about an inch under ground, in 

 a little chamber, which had apparently been excavated for their re- 

 ception ; the entrance to this chamber was only sufficiently large to 

 allow free access to the bee. 



The cells are constructed of mud ; the outer surface is irregular, 

 the inner perfectly smooth, reminding one of a swallow's nest. Each 

 cell is about five lines in length, and nearly egg-shaped ; there is, 

 however, a slight approach to the cylindrical form towards the upper 

 end, which is truncated, and is closed by a lid, the upper surface of 

 which is concave. 



I frequently observed the female Osmia laden with little pellets of 

 mud used in the construction of the cells ; but as these pellets were 

 always dropped upon my capturing the insect, I could not ascertain 

 how they were carried ; they appeared however to be held under the 

 thorax by means of the two anterior pairs of legs. 



In the newly-formed cells, which could be distinguished by the up- 



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