Note:  Do not rely on this information. It is very old.

Muscidae

Muscidae, the largest family of Diptera, including most of the common species, and nearly half the known species, of the order. They are mostly small. The largest European species (Echinomyia grossa, Linn.) being only inch long. As a rule, their hues are dark, and not highly coloured; but some species, such as the Australian Rutilia, are of a brilliant metallic green. The familiar small house-fly (Musca domestiea, Linn.) lays its eggs in dunghills; the adult often carries about one of the small parasitic chelifers, and it is also infested by the mould Empusa mnscaru.m. Those attacked by the latter can often be found attached to windows by the fungus. The larvae of most flies are parasitic on other insects - thus, e.g. that of Echinomyia grossa on butterflies, moths - but they attack other animals; thus, the Sarcophagce are parasitic on worms, and the Sarcophila on mammals, including man. These lay their eggs in the ears or nose, and the larvse eat their way into the flesh. The Muscidce are divided into two main groups: the M. calypterce, in which the wings have a pair of lobe-like appendages (the alulae) well developed; in the second division, the M. acalypterce, these structures are rudimentary or absent.