while others of the flock attach themselves one to the other, in such numbers that they have been observed © 99 nearly of the size of a bushel measure. It was very numerous in the town of Perth until abo sed : ae end of May, when I saw it in countless numbers flying in company with did I observe it again until near the y> the Common Swallows and Martens over a lake about ten miles north of the town; so numerous, in fact, were they, that they darkened the water as they flew over it. Its voice greatly resembles that of the Common Swallow in character, but 1s much more harsh. The stomach is muscular and capacious, and the food consists of insects generally. The season of incubation is from September to December. ‘The situation of the nest is much varied | have seen one placed in a thickly foliaged bough near the ground, while others were in a naked fork, on the side of the bole of a tree, in a niche formed by a portion of the bark having been separated from the trunk, &ec. The nest is rather shallow, of a rounded form, about five inches in diameter, and composed of fine twigs neatly lined with fibrous roots. I observed that the nests found in Van Diemen’s Land were larger, more compact and more neatly formed than those on the continent of Australia ; and one which was shown me by Mr. Justice Montague on his picturesque estate at Kangaroo Point, near Hobart Town, was placed at the extremity of a small leafy branch, as represented in the Plate. The eggs are generally four in number ; they differ much in the disposition of their markings ; their ground-colour is dull white, spotted and dashed with dark umber-brown ; in some a second series of greyish spots appear as if beneath the surface of the shell; their medium length is eleven lines, and breadth eight ut the middle of April, when I missed it suddenly, nor lines. Head, neck, and the whole of the body fuliginous grey; wings dark bluish black, the external edges of the second, third and fourth primaries white ; tail bluish black, all the feathers except the two middle ones largely tipped with white ; irides dark brown ; bill blue with a black tip; feet mealy lead-colour. The sexes are alike in the colouring of their plumage, and are only to be distinguished by the female being somewhat smaller in size. The young have an irregular stripe of dirty white down the centre of each feather of the upper surface, and are mottled with the same on the under surface. The Plate represents a male and female of the natural size.