Insects. 739 



been obligingly furnished with some ; they are the shells of Helix 

 aspersa. 



In the collection of the Rev. F. W. Hope, are a number of speci- 

 mens of a species of Osmia, smaller, but very closely resembling our 

 O. tunensis, which were bred from snail-shells collected in Egypt, on 

 the banks of the Nile. 



It is very probable that other species of this genus occasionally 

 construct their cells in the tubes of shells. Osmia caerulescens and 

 O. leucomelana have both been captured on the same slope where the 

 shells containing the nests of the other species were found ; the latter 

 in great abundance. Previous to the year 1836, O. leucomelana was 

 considered a rare species ; at that time I captured both sexes, enter- 

 ing bramble-sticks : this was in Hampshire, in July, as recorded in 

 the ' Magazine of Natural History,' 1837, p. 490, thus establishing 

 the supposed sexes of the species. Last summer, I found in the same 

 locality, some bramble-sticks containing the nests of this bee ; the 

 following are the observations made on its operations. The bee does 

 not clear the pith entirely out, but forms a somewhat serpentine tube, 

 between three and four inches in length ; here would be the top of 

 the first cell. Each cell is four lines in length, the bee therefore al- 

 ternately widens and contracts the diameter of the tube every two 

 lines, and thus forms somewhat barrel-shaped receptacles for the pro- 

 vision about to be stored up. Having formed four or five of these 

 spaces, she fills the farthest cell with pollen and honey, and deposits 

 an egg on the mass : the egg is white, and of the shape of a caraway 

 seed, but rather less pointed at the extremities. In about six or eight 

 days the young grub appears, and commences feeding on the provi- 

 sion, which consists almost entirely of honey at the end where the 

 young larva is hatched, but is afterwards of a more firm consistency. 

 In ten or twelve days the food is all devoured, after which the larva 

 remains inactive for a day or two, when it spins a thin silken cocoon, 

 in which it remains in a lethargic state until spring, when it assumes 

 the pupa state, and after again remaining inactive for some weeks, it 

 throws off a thin pellicle, and begins gradually to change colour, and 

 by slow degrees acquires its perfect state in June. The cells have 

 merely a thin partition, formed of some vegetable matter, as abraded 

 leaves &c, easily soluble in water. The parent bee does not line the 

 cells in any way : their number is usually four. Mr. Thwiates, of 

 Bristol, has also, I am told, bred the same species from bramble-sticks. 



Osmia spinulosa I have observed entering its burrows in hard sand- 



