This species, the largest of the genus yet discovered, is a native of Van Diemen’s Land, where it inhabits forests and thick scrubby situations, and is very generally dispersed over the island from north to south; I observed it also on Flinders’ Island in Bass’s Straits, but no instance has come under my notice of its occurrence on the continent of Australia. It is rather recluse in its habits, and were it not for its oft-repeated, loud, sharp, liquid, whistling note, its presence would not often be detected. I usually met with it in the thickest parts of the forests, where it appeared to resort to the ground rather than to the branches, and to frequent gulleys and low swampy situations beneath the branches of the dwarf _Eucalypti_ and other trees, with which its olive colouring so closely assimilated, that it was very difficult to perceive it. Although I felt assured that the bird was breeding in many parts of the country, and made repeated attempts to discover its nest, I could never succeed in so doing; the eggs are therefore among the desiderata of my cabinet. But little outward difference is observable in the sexes; the male is rather the largest and has the head of a sooty greyish brown, while the head of the female is olive-brown. The young resemble the female, and assume the adult colouring at an early age. The stomachs of several specimens dissected were very muscular, and contained the remains of coleoptera and hemiptera mingled in some instances with small stones and seeds. Crown of the head and ear-coverts dark brown; back, wings and tail chestnut-olive, the chestnut predominating on the back; throat greyish white, each feather tipped with brown; chest, abdomen and under tail-coverts reddish brown; bill black; irides reddish brown; feet mealy reddish brown. The Plate represents a male and a female of the natural size. [Illustration: COLLURICINCLA HARMONICA. _J. Gould and H. C. Richter del et lith._ _Hullmandel & Walton Imp._ ] COLLURICINCLA HARMONICA. Harmonious Colluricincla. _Turdus harmonicus_, Lath. Ind. Orn. Supp. p. xli. _Harmonic Thrush_, Lath. Gen. Syn. Supp., vol. ii. p. 182.—Shaw, Gen. Zool., vol. x. p. 217.—Lath. Gen. Hist., vol. v. p. 120. _Grey-headed Thrush_, Lath. Gen. Hist., vol. v. p. 118. _Collurincla cinerea_, Vig. and Horsf. in Linn. Trans., vol. xv. p. 214.—Jard. and Selb. Ill. Orn., vol. ii. pi. 71.—Less. Traité d’Orn., p. 374.—Ib. Man. d’Orn., tom. i. p. 131.—Swains. Class, of Birds, vol. ii. p. 221.—G. R. Gray, List of Gen. of Birds, 2nd Edit., p. 49. _Lanius Saturninus_, Nordm. _Turdus dilutus_, Lath. Ind. Orn. Supp., p. xl?—Bonn, et Vieill. Ency. Méth. Orn., part ii. p. 660? _Dilute Thrush_, Lath. Gen. Syn. Supp., vol. ii. p. 182?—Shaw, Gen. Zool., vol. x. p. 208?—Lath. Gen. Hist., vol. v. p. 120?