a ( Leper * \retue wterna { ( ARCTIC TERN. Sterna Arctica, Temm. L’Hirondelle de Mer arctique. Ir is to M. Temminck that we owe the knowledge of the present bird as constituting that of the Common Tern (Sterna Hirundo, Linn.), to which it bears so close a resemblance as almost to require actual comparative examination of the two species, to determine the characters which form the tion :—the accurate representation, however, which we have given of both species a different species from line of distine- , with the minute indications pointed out in the letter-press, will, we trust, clear up every difficulty attached to these two species, so nearly allied, and so often confounded. We have ourselves had abundant proofs that the present bird is a constant inhabitant, in considerable numbers, of many parts of our coast, but more especially its northern portion, and the adjacent Islands the Orkneys and Shetland, where it is known to breed regularly ; and it is not a little singular, according to the most credible information, that these Terns, although bearing so close an affinity to each other, do not associate together at the same breeding-places, but that each retains its peculiar locality although both breed in the immediate neighbourhood of each other. Thus one species will occupy an island, or a portion of it, to the entire exclusion of the other, and vice versa. M.Temminck informs us, that it is especially common in the Arctic circle, which he considers to be its true habitat, and where it occupies the place of the Sterna Hirundo of more southern latitudes. We have had opportunities of examining this species in all its stages, and we find that they strictly correspond with those of its allied congeners. The young offer also but little difference from those of our Common Tern. There is, however, one infallible rule by which not only the adult but the young in any stage may be at once discriminated, viz. by a comparison of the length of the beak and tarsus, characters on which the greatest reliance may always be placed. The Arctic Tern is altogether smaller and more slender, with a longer and more elegant tail, the beak wholly red and much less robust, as well as a quarter of an inch shorter, measuring from the gape to the tip; the tarsi are also proportionately smaller, measuring in length only seven lines ; to which may be added that its colour is much more uniform, nearly the whole of its body, both above and below, being covered by a blueish ash colour; the head and back of the neck black. 3 It breeds among the shingles on the sea shore, the female laying two or three eggs very similar in colour and markings to those of the Common Tern, but smaller. We have figured a male in its summer plumage. ~ ¥ / 0 “ Dy AS an oJ D235, xe. euE ) Ww ) oy “ VEILS <0 ™. DO os oO) a el he > i > a 2 OY Fe S f) JEON):