15. LARU8. 199 



Larus cirrhocephalus, Milne- Edwards &f Grandidier, H. N. Madag., 

 Ois. p. 043 (1882 : inland Lakes to centre of Madaofascar). 



Larus poliocephalus, Ilolub ^ Pelz. Beitr. Orn. Sudafr. p. 332 (1882). 



? Larus hartlaubi, Rochehrune, Faun. Seneg., Ois. p. 334 (1884 : 

 Gambia). 



Adult male in hreedinri-plumage. Head, napo, and throat lavender- 

 grey, palest on the forehead and gradually darkening until the tint 

 becomes plumbeous at the junction with the pure white neck ; 

 eyelids white ; mantle pearl-grey, wing-coverts and secondaries 

 darker ; the two outer primaries black, with white subtermiual 

 mirrors : 3rd quill black, with a smaller white mirror and some 

 white high up on the outer web ; 4th and 5th with a considerable 

 increase of white down the outer webs, the shafts, and the adjacent 

 portions of the inner webs ; 6th quill grey — passing into white on 

 the outer web to within 1 in. of the black subterminal bar, the 

 extreme tip white ; 7fh lead-grey, with a black subterminal bar and 

 edge to the inner web, and a whitish tip ; remaining inner quills 

 plumbeous, with indications of a darker subterminal bar ; tail and 

 under surface white ; under wing and axillarios lead-grey : bill, 

 tarsi, and toes crimson or lake-red ; iris yellowish white (in recent 

 examples). Total length 16 inches, culmen 1'8, wing 12'5, tail 5-25, 

 tarsus 2-1, middle toe with claw 1-9 to 2. In less mature birds 

 (the majority) there is no mirror on the 3rd and less white on any 

 of the quills. The dimensions of iha female arc a trifle less. 



Adidt in ivinter. Like the above, except that the head is white 

 for a short time. 



Young. Head white, with dark auricular patches ; mantle grey, 

 faintly mottled with brownish ; feathers of the upper wing- 

 coverts and the long inner secondaries with clove-brown centres ; 

 the remaining secondaries chiefly ash-brown ; the primaries much 

 as in the adult, except that there are no white mirrors on the two 

 outermost ; tail white, with a narrow umber-brown subterminal 

 band ; under surface white : bill yellowish, blackish at the tip ; 

 tarsi and toes deep brown. 



Immature. Similar, but with less brown on the upper surface, 

 and a commencement of the white mirror on the shaft of the outer- 

 most primai'y. By September (which corresponds to our March) 

 the full grey head has been assumed, and there is a red tingo on the 

 bill and feet. 



Hah. Brazil, from a little north of Rio de Janeiro, southwards 

 to the La Plata and the Province of Buenos Ayres, but hardly 

 below Bahia Blanca ; up the Parana valley to Matto Grosso, 

 probably crossing by that way to the coast of Pei-u, where the 

 bird is found occasionally. In Africa, from Sencgambia down to 

 Walvisch Bay on the West side ; inland on Lakes Ngami, Victoria 

 Nyanza, Tanganyika, and Shirwa ; on the East coast, at Durban. 



At one time I thought that the American and the African 

 forms might be distinguished, but the examination of a larger 

 series of specimens has altered that o])inion. The distance between 

 West Africa and Brazil is inconsiderable, and there are reasons 

 (which need not bo given here) for believing that the species crossed 



