The only known species of this form is confined to the interior of the southern and eastern parts of Australia, where it inhabits stony ridges, and is mostly observed on the _Callitris_. 268. Struthidea cinerea, _Gould_ Vol. IV. Pl 17. In my account of this species, I have stated that its actions are very similar to those of the _Corcorax leucopterus_, and the following extract from Mr. Gilbert’s Journal of his overland journey to Port Essington shows that the two birds assimilate still more closely in their nidification:— “Oct. 19.—Strolled about in search of novelties, and was amply repaid by finding the eggs of _Struthidea cinerea_. I disturbed the bird several times from a rosewood-tree growing in a small patch of scrub, and felt assured it had a nest, but could only find one, which I considered to be that of a _Grallina_; determined, if possible, to solve the difficulty, I lay down at a short distance within full view of the tree, and was not a little surprised at seeing the bird take possession of, as I believed, the _Grallina’s_ nest; I immediately climbed the tree and found four eggs, the medium length of which was one inch and a quarter by seven-eighths of an inch in breadth; their colour was white, with blotches, principally at the larger end, of reddish brown, purplish grey and greenish grey; some of the blotches appearing as if they had been laid on with a soft brush. From the appearance of the nest I should say it was an old one of a _Grallina_, but it contained a much greater quantity of grass for a lining than I ever observed in the nest of that bird; if this be not the case, then the nests of the two birds are precisely similar, being like a great basin made of mud, and placed on a horizontal branch. “Oct. 21.—In the evening I again met with the _Struthidea_, which I disturbed from a nest like the one above described, and from the new appearance of the structure I am inclined to believe it to be constructed by the bird itself, although it does so closely resemble that of _Grallina_, especially as in this case the nest was placed in a situation far from water, and there were no _Grallinæ_ in the neighbourhood. This nest, like the last, had a very thick lining of fine grass, and appeared as if just finished for the reception of the eggs.” There is no doubt that the nests above described by Mr. Gilbert were those of _Struthidea_; those of _Corcorax_ and _Grallina_ are precisely similar; and it is somewhat singular that three birds differing so much in structure should build the same kind of mud nests. Family CORVIDÆ, _Leach_. Genus CORVUS, _Linn._