144 
the department of Yonne, France, has recently furnished some details of the habits 
of the Osmya Bicolor and the Osmya Helicicolci. These insects are nearly allied 
to the Bee, but form their nests in the deserted shells of the Snail; he has divided 
them into two species, the first is only found nidified in the Helix nemoralis, and 
the second most frequently in the Helix pomatia. The O. bicolor , lays two eggs 
in each shell, the female egg being always placed uppermost; above these are con¬ 
structed three or four cells of sand, separated from each other by a membranous 
partition. The Osmya helicicola deposits ten or twelve eggs separated from each 
other by distinct partitions, each being provided with a magazine of honey ; but 
they do not wall in the different strata, either with sand or any other earthy 
matter placed above the domicile of their progeny. They sometimes form their 
nest in the Helix nemoralis , in which they lay several eggs, closing the entrance 
with a thick division formed of minute fragments of leaves, triturated with the 
salivated excretion of the insect, and arranged in successive layers. 
Mr. Desvoidy has also found in the nymphae of those two species of Osmya 
a parasitical insect, which he, in the first instance, considered an Ichneumon, but 
has since determined it to be a pupivorous hymenoptera, of the genus Eulophus , 
hitherto undescribed ; he has, therefore, named them Eulophus osmiarum. These 
larvae change into nymphae without spinning a coccoon, or quitting the place of 
their birth. 
Another insect is found inhabiting the vacant shells of Snails ; it is the Sopy- 
ga punctata : which passes its two stages of metamorphose in the cells of the 
Osmya, and are themselves sometimes tormented by the Ichneumon. 
The same entomologist observes that the Asylus diadema —a species of insect 
hitherto only found in France, near Marseilles—is also met with at St. Sauveur, 
and may be classed with the enemies of the domestic Bee, which they seize with 
their feet, and bury in holes Excavated for that purpose. This appears to be the 
only instance of dipterous insects being grave-diggers, which renders Mr. Des¬ 
voidy’s discovery highly interesting. Of several examples of the Asylus diadema 
which this naturalist took in the act of carrying off their prey, all proved, on exa¬ 
mination, to be females, and the Bees were doubtless buried to serve as a future 
provision for the larvae of its ravisher. 
Another interesting fact is mentioned of a species of dipterous insect, the 
Conops auripes, which torments the Bomhus hortorum, as Mr. Desvoidy ima¬ 
gines, for the purpose of depositing its eggs on the surface, or between the annular 
segments, of that insect’s body. The genus Conops are, at present, the only insects 
described as living even in the bodies of other insects which have attained an adult 
perfect state; other analagous species only living on the larvae, and still more 
generally on the nymphae. Mr. Desvoidy adds that the apodous larva found in 
the body of a Bombus, and described by Messrs. Audouin and Lachat, most 
probably is a species of the genus Conops. 
