Mr. Bartlett draws the following distinction as to the colouring of the two supposed species :—“Ap. Australis: Colour pale greyish brown, darkest on the back. Ap. Mantelli: Colour dark rufous brown, darkest on the back.” The above descriptions are applicable, the former to the female and the latter to the male of the common species. Mr. Bartlett, in giving his measurements of the two birds, properly observes that the entire length, being taken from skins, is of very little value; but the difference in the general proportions (amounting to two inches in the length of the bill) is also characteristic of the two sexes, the female being considerably larger than the male. The condition of wing, ascribed by Mr. Bartlett to Ap. australis, “with soft slender quills” (as figured in the Proc. Zool. Soc.), is that of the young bird. The length of the “straggling hairs on the face” varies in almost every individual, and is certainly of no value as a specific character. Mr. Bartlett's strongest point is that one species has the tarsus scutellated in front, while in the other it is reticulated. The descriptive and comparative notes which I have collected on this point are too lengthy to be given here, but they will appear in my forthcoming work on the Birds of New Zealand. To summarize, I may state that I have found so great a diversity of character in the size and arrangement of the tarsal scales in different examples, that I do not attach very much importance to those peculiarities of structure in this respect, which Mr. Bartlett deems of specific value. I have observed a gradation from a regular series of quadrangular scutes, protecting the whole anterior portion of the tarsus, to a reticulated surface of large irregular scales, those towards the distal end being broadest. The latter condition appears to be characteristic of the immature bird, the scales being detached from each other and not imbricated, or with overlapping edges, as in the adult. Figures 1 and 2 (.Plate XII.b.) represent the wing and foot in an ordinary adult female of the common species, the so-called Ap. Mantelli. 18. Ardea Sacra, Gmelin. It is satisfactory to find that our Blue Heron (Ardea matook) has been finally identified with Ardea sacra of Gmelin; and that we are thus enabled to purge our list of so gross a corruption of the Maori, as “matook” for “matuku.” 19. Rallus Pectoralis, Lesson. I think we are perfectly justified in considering our Rallus assimilis identical with R. pectoralis, the more so as Drs. Finsch and Hartlaub have been compelled to reduce their Rallus Forsteri to a synonyme of that species. In a paper communicated to the Zoological Society of London (November 26, 1869), they observe:—“It is certainly disagreeable to kill one's own