642 



SABINE S GULL. 



it is merely a visitor to Jan Mayen. In the Atlantic it has not been 

 met with further south than the Bermudas ; but in the Pacific it 

 not only crosses the equator, but goes as far as 12° S., two nearly 

 a'dult specimens in winter-plumage having been presented to me by 

 Capt. A. H. Markham, R.N., from Callao Bay, where Staff-Commr. 

 MacFarlane afterwards found it in swarms during the month 

 of February. It thereby overlaps the habitat of the far larger 

 X. furcata, another fork-tailed species, only three examples of 

 which are known. 



The eggs, 2 in number, are laid on the bare ground, or on 

 dry tussocks in marshes near the sea — frequently in proximity to 

 those of the Arctic Tern, with which species this Gull often asso- 

 ciates ; their colour is dull brownish-olive with somewhat darker 

 blotches near the larger end, much like those of the Arctic Skua 

 in miniature: average measurements 17 by i"3 in. The nestlings, 

 which are hatched towards tlie end of July, are at first mottled with 

 brown and dull yellow. The food consists of small fish, crusta- 

 ceans, worms, insects and their larva; ; the note is harsh and 

 clicking. 



The illustration of the adult in summer-plumage renders a detailed 

 description unnecessary : the head and neck are lead-grey, encircled 

 by a black collar, and the mantle is slate-colour. Length 14 in. ; 

 wing 1075 in. In winter the crown and forehead are white, but 

 there is more or less black on the nape. The young bird in the 

 l)lumage of the first autumn (figured below) is ash-coloured on the 

 upper parts, barred with brown and dull white ; and, when still 

 younger, has a dark gorget. 



