Only one species, the _C. atratus_, is, I believe, found south of the line; for the Black-necked Swan of Chili will doubtless prove to be generically distinct.
This “rara avis in terris” is not only strictly confined to Australia, but is so exclusively an inhabitant of the southern districts, that no notice has been recorded of its having been seen in Torres’ Straits, or on any part of the north coast.
This ornamental section of the _Anatidæ_ is not very numerous in species.
545. Casarca Tadornoïdes Vol. VII. Pl. 7.
A beautiful representative of the _C. rutila_ of Europe.
An equally beautiful representative of the _T. Vulpanser_.
Of true Ducks three species are found in Australia.
547. Anas superciliosa, _Gmel._ Vol. VII. Pl. 9.
This bird assimilates very closely in its structure and in its economy to the _Anas Boschas_ of Europe, but in its plumage it is very different.
548. Anas nævosa, _Gould_ Vol. VII. Pl. 10.
A very singular Duck, perhaps more nearly allied to _Chaulelasmus_ than to _Anas_. It is a very rare bird, and has only yet been seen on the western and southern coasts of Australia; its true habitat is probably the distant interior.
549. Anas punctata, _Cuv._ Vol. VII. Pl. 11.
This species has much the appearance of the Teal (genus _Querquedula_), but in its structure is nearly allied to the true ducks (genus _Anas_), with which I have provisionally placed it.
The great continents of America, Africa, Asia and Australia, are each inhabited by one or more species of this restricted genus.
550. Spatula Rhynchotis Vol. VII. Pl. 12.
This bird is, I believe, restricted to Australia.
A very delicate form, of which the single species, confined to Australia, is the only one known.
551. Malacorhynchus membranaceus Vol. VII. Pl. 13.
This form is found in India, Africa, America and Australia: the bird I have separated into a distinct genus, under the appellation of _Leptotarsis_, should be included in this genus, the difference which it presents being too slight to warrant their separation.
552. Dendrocygna arcuata Vol. VII. Pl. 14. 553. Dendrocygna Eytoni. Leptotarsis Eytoni, _Gould_ Vol. VII. Pl. 15.
“Many of the reaches,” says Captain Stokes, when speaking of the river Adelaide of the north-western part of Australia, “swarmed with wild fowl, consisting almost wholly of ducks, which, from a habit of perching on the trees, have received the name of Wood Ducks. Their singularly long legs, with the web very much arched near the toes, gives great pliability to the foot and a power of grasping, which enables them to perch on trees. When on the wing they make a peculiar pleasing, whistling sound, that can be heard at a great distance, and which changes as they alight into a sort of chatter. Their perching on trees is performed in a very clumsy manner, swinging and pitching to and fro. We subsequently often found them on the rivers of the north coast, but not within some miles of their mouths or near their upper waters, from which it would appear that they inhabit certain reaches of the rivers only; we never found them in swamps. The farthest south they were met with was on the Albert River, in the Gulf of Carpentaria, in lat. 18° S., which gives them a range of six and a half degrees of latitude over the northern part of the continent. These ducks are the _Leptotarsis Eytoni_ of Mr. Gould.”