DOMINICAN GULL 211 
the mud-banks at the head of the harbour, in the 
same manner as on the grassy plains near the Parana ; 
and every evening they took flight direct to seaward. 
From these facts I suspect that the Rhynchops 
generally fishes by night, at which time many of the 
lower animals come most abundantly to the surface. 
M. Lesson states that he has seen these birds open 
the shells of the Mactre, buried in the sand-banks 
on the coast of Chili; from their weak bills, with 
the lower mandible so much produced, their short 
legs and long wings, it is very improbable that this 
can be a general habit.” 
DOMINICAN GULL 
Larus dominicanus 
Mantle brownish-black; primaries black, with white tips, and a 
subapical patch in old birds; rest of plumage white; bill yellow, 
orange at angle of lower mandible; legs and feet olive; length 22, 
wing 18 inches. 
THE Dominican Gull, which belongs to the same 
section of the group as the well-known Black-backed 
Gulls of Europe and closely resembles our Great 
Black-backed Gull, is common throughout the Plata 
district in winter, from April to August. During the 
summer months it confines itself to the Atlantic 
coast, and breeds in large numbers in the neigh- 
bourhood of Bahia Blanca, on the extensive sand- 
banks and mud-flats there; and in other suitable 
localities further south. Durnford found it nesting at 
Tombo Point, sixty miles south of the Chupat river. 
