1874.] MR. H. SAUNDERS ON THE GREY-CAPPED GULLS. 293 



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 my best to 

 unravel. To do this it will be better to take them separately. 



L. pheeocephalus is identified by Bruch (J. f. O. 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 pos- 

 sibly 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 re- 

 semblance to the former, and it also has the under wing-coverts of a 

 smoke-grey ; but it is altogether a smaller bird than L. pheeocephalus, 

 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. scopulinus, Forst., of New Zealand, L. novce kollandice, L. 

 jamesoni, and perhaps L. pomare, into whose specific distinctness 

 it is not my present intention to enter. Another point which di- 

 stinguishes it from L. pheeocephalus exists in the seventh primary, 

 which has a broad dusky bar right across it and is altogether darker 

 in the grey-capped bird, whilst in L. hartlaubi it is uniform grey, 

 just fringed with smoke-colour on the inner web ; the colour of the 

 legs and bill is also deep lake-red. Blasius says (loc. cit.) that, as 

 a rule, L. pheeocephalus, Sw., figures as L. hartlaubi in collections ; 

 but according to my experience the reverse is the case ; and, with one 

 solitary exception in the British Museum, all the specimens which 

 I have examined marked " L. pheeocephalus" are really L. hart- 

 laubi. Layard (B. S. A. p. 368) has also confounded these two 

 species, having obtained both. 



When we turn to L. cirrhocephalus of South America we find a 

 different element of confusion, owing to the presence there of a 

 species which certainly has a hood, although in this case it is a 



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