This new species may be distinguished from all its congeners by the uniform colouring of its plumage; it is in fact a most remarkable bird, inasmuch as I scarcely recollect one similarly coloured in any genus that has come under my notice. I regret that, as regards the history of this Honey-eater, its range over the Australian continent, its habits and economy, all is a perfect blank; a single specimen is all I have at present seen; this was procured by one of the officers of Her Majesty’s Ship the Beagle, while employed on the north coast. The names of Captain Stokes, Lieutenant Emery and Mr. Bynoe have been repeatedly mentioned in this work, with feelings of personal gratification that their labours have been useful to science. It now only remains for me to describe the colours of this bird; having I trust thrown out a sufficient hint to those who may visit its native country, and may have opportunities of observing it, that any contributions to its history will be very desirable. Head and all the under surface delicate citron-yellow, the yellow prevailing over the head; immediately under the ear-coverts is a spot of blackish brown, posterior to which is a patch of bright yellow, the remainder of the plumage olive-grey. The Plate represents the bird in two positions of the natural size. [Illustration: PTILOTIS PENICILLATUS: _Gould_. _J. Gould and H. C. Richter del et lith._ _Hullmandel & Walton Imp._ ] PTILOTIS PENICILLATUS, _Gould_. White-plumed Honey-eater. _Meliphaga penicillata_, Gould in Proc. of Zool. Soc., Part IV. p. 143; and in Syn. Birds of Australia, Part I. This species, which is rarely met with in New South Wales, is very abundant in South Australia; I met with it even in the streets and gardens of Adelaide, where it strongly reminded me of the Sparrow of our own island; and it doubtless enjoys a wide range over the interior of the country. From what I observed of its habits, it appears to differ from the generality of Honey-eaters in the partiality it evinces for the ground; for although most of its time is spent among the leafy branches of the gums and wattles, where its movements are characterized by ease and grace, it is often to be seen hopping about under the trees in search of insects and seeds, which with the pollen of the flowers of the _Eucalypti_ and _Acaciæ_ constitute its food. Its silvery white neck-plumes present a character by which it is at once distinguished from all other known species. The smaller size of the female is the only external difference between the sexes, for when fully adult their markings are precisely alike. Some of the specimens killed had the bill entirely black, while others had the base of that organ of a yellowish white, which is doubtless indicative of immaturity.