feet are webbed to the extremities, and the young are for some time dusky on the under parts. The reason for laying stress on these particulars will be shown in treating of the next species.
Sterna anæstheta (originally printed S. anæthetus), Scopoli, Deliciæ Flora et Faunæ Insubricæ, i. p. 92, No. 72 (1786), ex Sonnerat's Voyages, p. 125, pl. 84, where the species is described as the Hirondelle de Mer de Panay (Phillipine Islands), whence it is sometimes called the Panay Tern, S. panayensis, Gm. (1788), &c. The range of this species is almost the same as that of its congener, whose example, as we have seen, it has followed in straggling as far as our coast, but the information we possess tends to show that it is rather less oceanic in its habits, and more inclined to hug the shore. In distribution of colour it resembles S.fuliginosa, but it is somewhat smaller in size; the mantle and wings are decidedly less sooty, the white from the frontal band extends both above and beyond the eye, and the web between the middle and inner toes only extends to the last joint of the latter, and does not come down to the claw; the young also are light on the under parts on emerging from the downy stage. A woodcut of the above differences in the formation of the feet of the two species will be found in my paper on the Sterninæ (Proc. Zool. Soc, 1876, p. 605).
The third species of the group is Sterna lunata, Peale, U.S. Expl. Exped.—Birds, p. 277 (1848). It is intermediate in size between the other two, has a more distinctly slate-gray mantle, and is altogether washed with a grayish tint; the webs of the feet are similarly incised with those of S. anæstheta, to which it is more closely related than to S. fuliginosa. Its range, so far as we know it at present, only extends from the Moluccas to the Phenix and Paumatu groups of the Polynesian Islands. I do not know of any specimens in collections in this country, but the Leyden Museum, which is far in advance of our national collection in Laridæ, possesses several examples.
The Sooty Terns have been separated generically from the true Terns by Wagler, and as one or other of his generic names have been pretty freely adopted, it may be edifying to consider them for a moment, for they supply an excellent sample of the way in which our scientific nomenclature is encumbered by useless and
