have never seen the latter bird away from the swamps of the South-West, but Circus assimilis is a common bird in the Gascoyne and more northern areas, and I certainly saw it on Dirk Hartog Island.
Field-Wrens (Calamanthus hartogi and C. peroni). In respect to these sub-species, Mr. Whitlock says: "It requires a fine discrimination to detect differences in plumage in local clans of a species separated from one another by a strait only about twenty miles wide." I shall deal with this point later on in this paper, but may say that when one lays out any series of skins like those of Calamanthi collected between the N.W. Cape and Lake Austin (Day Dawn), as I did at the Perth (Western Australian) Museum, with the kind assistance of Messrs. Alexander and Glauert, it is best to ignore the localities at first, and class the birds according to their respective resemblances or differences (as we did) in order to avoid any prejudice, and then. compare the labels. C. hartogi very much resembled the birds from Dorre Island, but the Peron specimens were quite distinct from the Dirk Hartog birds. As stated by me in the Ibis, 1917, p. 587, the Peron birds came nearest to C. rubiginosus and C. wayensis, but have differences, which I gave in my paper. On my return to England, a comparison between my specimens of skins from the North West Cape regions and the Peron confirmed these differences. However, we shall probably soon have Mr. A. J. Campbell's opinion about them. As I was not on Dirk Hartog during the breeding season, as Mr. Whitlock was, I did not see the C. hartogi in full breeding plumage, which may be a point in his favor.
Mr. Whitlock states that "no Acanthiza (Tit- Warbler) appears to inhabit Dirk Hartog," which coincides with my own experience. In the Ibis, October, 1917, p. 588, I stated that no Acanthiza was observed by me on the island, but in my diary I have an entry made by me on May 1, 1916, when at Cape Inscription Lighthouse, that I there saw a few birds that looked like the Yellow-tailed Tit-Warbler (Acanthiza chrysorrhoa), but no specimens were obtained (I think I had not my gun with me at the time); so being doubtful of their identity they were not recorded. It was the same date and place as the Tricoloured Bush-Chat (Ephthianura tricolor) were seen. A heavy N.E. gale was blowing at the time, which might account for stragglers of both the above species occurring temporarily on the island.
White-winged Wren- arbler (Malurus leuconotus). Referring to Mr. Whitlock's criticism of the coloured plate of this bird that appeared in The Ibis, October, 1917, it was certainly drawn and coloured by the artist from a skin, and not from a specimen in the flesh. The skin was selected by myself from a series then in mv collection (mostly collected from the Gas-
