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the department of Yonne, France, has recently furnished some details of the habits 

 of the Osmya Bicolor and the Osmya Helicicola. 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 

 larva? 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 Bombus 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. 



