ACANTHIZA PYRRHOPYGIA, Goud. Red-rumped Acanthiza. Acanthiza pyrrhopygia, Gould in Proc. of Zool. Soc., 1847. Tis species differs from the Acanthize Diemenensis, pusilla, Ewingti, and apicalis, in having a shorter and more robust bill, and in the greater depth of the red colouring on the rump and upper tail-coverts ; it also differs from the three former in having the tail tipped with white, in which respect it assimilates to the A. apicalis and A. uropygialis, to the former of which it is most nearly allied. I discovered this species in the Belts of the Murray, where it inhabits the small shrubby trees ; upon first seeing it, I at once perceived that it was a distinct species by the red colouring of the rump, which showed very conspicuously at the distance of several yards, and also by the peculiarity of its note. In its actions it very closely assimilates to the other members of the genus, being an alert and quick little bird, carrying its tail above the level of the back, and showing the red colouring of the coverts to the greatest advantage. I succeeded in killing both sexes, and found that they exhibit no outward difference, and are only to be distinguished with certainty by dissection. All the upper surface and wings olive-brown, the feathers of the forehead margined with buff; wings brown with pale edges; throat white, each feather margined with black ; abdomen whitish ; flanks pale buff; upper tail-coverts rufous ; tail olive, crossed by a broad band of black, and tipped on the outer webs with pale olive, on the inner webs with white ;_ bill blackish brown, under mandible somewhat lighter ; feet brown ; irides reddish brown. The figures are of the natural size.