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Show 1874.] MR. H. SAUNDERS ON THE GREY-CAPPED GULLS. 293 hood, but much lighter than the under wing-coverts, which are of a deep smoke-grey; underparts and tail pure white. But it will be observed that there is a considerable difference both in the size and in the coloration of the soft parts of the two species ; and this is much more noticeable on handling the different specimens than can be gathered from any mere description. It must be admitted that Swainson in his original description states that the bill and feet of the African bird are "deep crimson ;" but, with every allowance for fading, I cannot imagine the colour in those I have examined to have ever been more than "orange-red," very different from the livid red or brilliant lake-colour of the American specimens. Of course I am now alluding to adults only; but, as regards size, a glance at the coarser and stronger feet even in the immature American birds would enable me to distinguish them from the African form. Without, however, insisting too strongly upon the value of these differences, I consider that the two forms are at least as much entitled to specific distinction as L. glaucus and L. leuco-pterus, or L. marinus and L. fuscus, to say nothing of the species which surround L. argentatus. This conclusion is in no way influenced by the fact of the two species being found in different continents; for I am at the present moment unable to separate the Saddle-backed Gulls which, under the titles of L. dominicanus, vetula, and anlipodum, with other synonyms, inhabit both the Atlantic and Pacific coasts of South America, the south coast of Africa, New Zealand, and many of the intervening islands. It would seem that these Grey-capped Gulls are representative species on either side of the South Atlantic, in the same way that L. heermanni on the west coast of America replaces L. crassirostris, Vieill. (L. melanurus, Temm.), in the Japan and China seas-not to quote other instances which are not quite so evident. But the question of the distinctness of these two forms is a mere trifle to the maze of confusion in which both these and two totally different species have been involved, and which I will do m y best to unravel. To do this it will be better to take them separately. L. phaocephalus is identified by Bruch (J. f. 0. 1855, p. 290) with L. ridibundus ; but he could never have seen a true specimen. Finsch and Hartlaub (Vog. Ost.-Afr. p. 825) describe the real bird from Bissao with a grey head, but are probably wrong as regards the specimen with a white head from the Cape of Good Hope, received through Verreaux. Blasius again (J. f. O. 1865, p. 376) may possibly have had a specimen of the Grey-capped Gull in immature plumage before him; but he goes on to confound it with L. hart-laubi, Bruch, a species which that author places in his genus Gavia, close to Gelastes. This latter species has a certain superficial resemblance to the former, and it also has the under wing-coverts of a smoke-grey ; but it is altogether a smaller bird than L. phaocephalus, the wing being only 11 inches and the tarsus 1*7 in length ; besides which, it never has a hood. It is a coast resident, and breeds near the Cape of Good Hope ; it is, in fact, a member of the same group as L. scopidinus, Forst., of New Zealand, L. nova hollandia, L. |