Fig. 151.—Gastrophilus Equi (Mag.)
Section 2, namely Acalypteræ, contains eight sub-families.
The species of Scalophaginæ are usually called "Dung-flies." The commonest species, the Yellow Dung Fly (Scatophaga stercoraria), feeds largely on manure and other refuse.
The Ortalinæ are flies of small or moderate size, which are met with principally in woods and fields. The Trypetinæ feed chiefly on fruit. One species, Ceratitis hispanica, is very destructive to oranges in the south of Europe, etc. Of the Piophilinæ, Piophila casei may be taken as the typical example. The larvæ which abound in cheese and bacon are popularly called "Cheese Hoppers," or "Jumpers," in allusion to their habit of springing. The Diopsinæ are principally met with in the tropical parts of the world. They are generally insects of moderate size. Most of the species of Chloropinæ are of small size. Their larvæ generally live in the stems of corn and various kinds of grasses. The Drosophilinæ are small, dull-coloured flies, the larvæ of which feed on fungi, rotten fruit, and similar substances.
Fig. 152.—Hypoderma Bovis (Mag.)
The last sub-family, namely, the Agromyzinæ, is very extensive. One of the commonest species is Phytomyza ilicis, the larva of which forms large brown blotches on the leaves of the holly.
Fig. 153.—Diopsis Subfasciata (Mag.)
Family 35, Phoridæ.—The insects belonging to this family are generally of small or moderate size. They are very active, and may be observed on plants, and also sometimes sunning themselves on windows.