The leaping power of the muscular tail is lost, and powerful claws have been acquired to assist in climbing, but in other respects the animal seems better adapted to walls on terra firma.

This imperfect adaptation may be due to the fact of there being no carnivore in New Guinea, and no enemies of any kind from which these animals have to escape by rapid climbing.

Four species of Cuscus, and the small flying opossum, also inhabit New Guinea; and there are five other smaller marsupials, one of which is the size of a rat, and takes its place by entering houses and devouring provisions.
The birds of New Guinea offer the greatest possible contrast to the Mammalia, since they are more numerous, more beautiful, and afford more new, curious, and elegant forms than those of any other island on the globe.

Besides the Birds of Paradise, which we have already sufficiently considered, it possesses a number of other curious birds, which in the eyes of the ornithologist almost serves to distinguish it as one of the primary divisions of the earth.

Among its thirty species of parrots are the Great Pluck Cockatoo, and the little rigid-tailed Nasiterna, the giant and the dwarf of the whole tribe.