I obtained this new and highly interesting species while encamped on the low grassy hills under the Liverpool range; from the manner of its ascending the trees and keeping almost entirely to the small upright stems of the _Casuarinæ_, I believed it to be the White-throated Tree-Creeper (_Climacteris picumnus_); but having made it a rule to shoot an example of every species I observed in each newly-visited locality, I was in this instance rewarded with the acquisition of a new bird, which I afterwards found was numerous in this part of the country. But whether it is generally distributed over the colony, or merely confined to such districts as have a similar character to those in which I found it, I had no opportunity of ascertaining. So far as I could observe, its habits and manners bore a striking resemblance to those of the _Climacteris picumnus_. One singular feature connected with this species, is the circumstance of the female alone being adorned with the beautiful radiated rufous markings on the throat, the male having this part quite plain; this I ascertained beyond a doubt by the dissection of numerous specimens of both sexes; it is true that a faint trace of this character is observable both in _Climacteris scandens_ and _C. rufa_, but the present is the only species of the genus in which this reversion of a general law of nature is so strikingly apparent. The male has the crown of the head blackish brown, each feather margined with greyish brown; lores and a circle surrounding the eye reddish chestnut; back brown; sides of the neck, lower part of the back, and upper tail-coverts grey; primaries blackish brown at the base and light brown at the tip, all but the first crossed in the centre by a broad band of buff, to which succeeds another broad band of blackish brown; two centre tail-feathers grey, the remainder blackish brown, largely tipped with light grey; chin dull white, passing into greyish brown on the chest; the remainder of the under surface greyish brown, each feather having a broad stripe of dull white, bounded on either side with black running down the centre, the lines becoming blended, indistinct, and tinged with buff on the centre of the abdomen; under tail-coverts buffy white, crossed by irregular bars of black; irides brown; bill and feet black. The female differs in having the chestnut marking round the eye much richer, and in having, in place of the greyish brown on the breast, a series of feathers of a rusty red colour, with a broad stripe of dull white down their middles, the stripes appearing to radiate from a common centre: in all other particulars her plumage resembles that of the male. The figures are those of a male and a female of the natural size. [Illustration: CLIMACTERIS MELANOTUS: _Gould_. _J. Gould and H. C. Richter del et lith._ _Hullmandel & Walton Imp._ ] CLIMACTERIS MELANOTUS, _Gould_. Black-backed Tree-creeper.