Flying Fhalanger, a name for several small marsupials of the genus Petaurus, and allied genera or sub-genera, from New Guinea and Australia, differing little from the true phalangers, except in that they have a patagium (q.v.). The largest is about the size of a cat, and the smallest no bigger than a mouse. They are nocturnal in habit, and feed on fruit and insects. It is said that they have been seen to modify their course when in motion through the air. P. australis is the Yellow-bellied, and P. scinreus the Squirrel Flying Phalanger, and P. pygmceus is the Opossum, or Flying Mouse.