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Show 1877.] MR. H. SAUNDERS ON THE LARIDSE. 795 assumed, and the bill and feet are still reddish black ; in the black head only is wanting to complete the nuptial dress; but the third is in full breeding-plumage, as is also a specimen in spirits. The specimen from Betsey Cove is a young bird just fledged, many particles of down still adhering; general colour sooty grey mottled with brown, and barred with black on the upper parts ; under wing-coverts white. This somewhat specialized form has hitherto been only found at Kerguelen Island, and appears to be more closely allied to the New- Zealand species S. antarctica, Wagler, than to the less restricted form S. vittata, which also includes in its range portions of the same island. The principal specific distinctions of the two species are given in my paper on the Sterninae above referred to. 3. STERNA VITTATA, Gm. Sterna vittata, Gm. Syst. Nat. i. p. 609* (1788); Saunders, P.Z.S. 1876, p. 647. [1 specimen. Inaccessible Island, Tristan d'Acunha, October 18th, 1873. 1 specimen. Royal Sound, Kerguelen Island, January 1874.] Both these specimens are adults in breeding-plumage ; but the latter is not a very old bird, the outer webs of the long tail-feathers being still slightly tinted with grey, whereas in really mature examples they are long and white. In pointing out its specific characters (l.s. ci), I gave its then known range as from Kerguelen Island up to St. Paul's and Amsterdam Islands, about 700 miles to the north, apparently its bead quarters, and as that of a straggler over the sea between St. Helena and Ascension ; but the fact of its having been obtained close to Tristan d'Acunha is an interesting extension of these limits. When treating of the few examples then available from the above-mentioned localities, I remarked that the affinities of this species were decidedly with S. hirundinacea, Less. (S. cassini, Scl.), of the extra-tropical coasts of South America and of the Falkland Islands ; and this view has subsequently been confirmed by the examination of a larger series brought home by the French naturalists from the Transit-of-Venus Expedition, at the same time that the two species are always perfectly distinguishable. But in the case of this individual from Tristan d'Acunha (its nearest known approach to South America), it is interesting to observe that, although the example is undoubtedly referable to S. vittata and not to S. hirundinacea, it comes nearer to the latter species than any other specimen yet examined. However, its relatively smaller size, grey colour, and the characteristic shortness of the foot and claws show distinctly that the bird in question is S. vittata ; and although it has a rather unusually long bill, yet there is an absence of the long curve characteristic of the American bird. It may be remarked that the bill in individuals of the present species seems to be peculiarly brittle and friable, which will account for the worn and blunted appearance often to be observed in the anterior portions of the mandibles. There are the remains of an egg, labelled as taken at Heard Island, |