404 Insects. 



per part being damp, there was always a small round hole in the lid, 

 about the size of a pin's head. This I imagined was left by the in- 

 sect, that it might insert additional food previous to the final closing 

 of the lid ; they already had some food in them. 



The food deposited in the cells for the larvae, consists, as in most 

 of the Apidse, of honey, with but a small admixture of pollen. The 

 honey must have been chiefly collected from Lotus corniculatus, that 

 being almost the only plant on which I observed the bee to settle. 



I have reared from the nests of this species of Osmia, several spe- 

 cimens of females, and two males. The insect has usually undergone 

 its transformation by the latter end of September, and always before 

 the winter commences. This I have found to be the case with very 

 many species of bees, and believe it will prove a general rule. Pro- 

 bably the perfect insect is better able to bear the effects of the winter 

 frosts than the pupa. A great portion of the Coleopterous insects, 

 especially the ground species, have undergone their transformations 

 before the winter. At what time Osmia atricapilla first makes its ap- 

 pearance, I am not able to say. I have found a male in the middle 

 of March ; it must be observed however that it was an unusually warm 

 day, and I suspect he had mistaken the month. He was crawling 

 slowly on the grass, could not fly, and apparently did not know what 

 to do with himself. I have said the females were abundant in the be- 

 ginning of June, at which time there were no males to be found ; and 

 taking matters as they stand, it seems immensely probable that, as 

 usual, the males come out first, and that about the end of April or 

 beginning of May. 



The male Osmia atricapilla is considerably less than the female — 

 length 5 J lines ; it has the fore part of the head covered with white 

 hair, and the vertex with reddish brown, like other parts of the body, 

 if we except the under surface of the thorax and its sides, where the 

 hairs are greyish white. 



In the female (which is usually about 6j lines in length), the head 

 is entirely covered with black hairs, the thorax, and two basal seg- 

 ments of the abdomen with hair of a bright brownish-red colour, and 

 on the apical portion of the abdomen, and the whole of the under 

 side of the body, the hair is black. 



I will hereafter send some observations on the mode in which the 

 cell is constructed. 1 do not do so now, because I wish to say, in 

 connexion with that subject, a word or two about the cells of some 

 other insects, and these I cannot at this moment lay my hand upon. 



Geo. R. Waterhouse. 



