Page:The Zoologist, 4th series, vol 5 (1901).djvu/386

358 Snipe, Long-eared Owl, and Green Woodpecker. Stenopteryx hirundinis, Linn., another member of the same group of flies, found only in the nests and upon the young of the House-Martin, is very similar in general appearance, but has lancet-shaped wings; while Oxypterum pallidum, Leach, has somewhat broader wings, and is confined to the Swift. The so-called "Sheep-tick" (Melophagus ovinus, Linn.), which is entirely destitute of wings, also belongs to this group.

The mode of reproduction of these flies is highly remarkable. The female is viviparous, and produces but a single larva at a time, which grows to a large size within the body of the mother before being extruded, being actually nourished by means of a sort of placental connection with the wall of the oviduct. As soon as it is deposited the larva turns into a dark brown shining pupa, whence the group of parasitic flies, to which Ornithomyia belongs, has been termed the Pupipara. Recently, however, a similar mode of reproduction has been stated to occur in the case of the Tsetse Fly (Glossina), which is a true Muscid, and a near relation of our common English Stomoxys; so that, if this is confirmed, the name Pupipara must be abandoned.— (Brit. Mus. South Kensington).