LARI— LARID.E 297 



/;;-^,V.9. —Coasts of Gulf of Mexico and S. Atlantic Islands. 

 Of casual occurrence in European waters, recorded France and 

 r>ritain. 



Xema. 



Tail forked; said to resemble Black-headed Gull in 

 habits ; eggs in a depression in moss, dull l)ro\vnish olive 

 blotched, chiefly at larger end, with distinct dull brown. 



Xema sabinii (Sabine). Sabine's Gull. 



(5 ? Head, nape and upper throat dark slate separated by 

 a narrow black collar from white lower throat and hind neck ; 

 upper parts pale slate ; outer wing coverts, inner primaries, upper 

 tail coverts, tail and underparts white ; outer primaries black 

 with white tips. Bill black, tipped yellow. Inside of mouth and 

 eye-rim vermilion. Legs and feet blackish grey. In winter, head 

 and neck white streaked grey. Wing 270-290. Tarsus 30-36. 

 Bill 24-28. $ generally the smaller. Young : forehead, throat 

 and underparts white ; above grey brown buff tipped ; outer wing 

 coverts and inner primaries white, tip of tail brown. 



Breeds. — As far as is known, Spitzbergen, N.E. Siberia 

 (Kolyma district) and Arctic N. America. Circumpolar in 

 distribution, has been met with Franz Joseph Land, Greenland ; 

 occurs in winter occasionally in Europe, on Atlantic and North 

 Sea Coasts. 



Rhodostethia. 

 Tail wedge-shaped; bill small, shorter than head. 



Rhodostethia rosea (Macgillivray). Ross's Gull. 



^ '^ summer. Above pale grey, tail white ; head and under- 

 parts white with bright rosy tinge, collar and outer web ist 

 primary black. Bill black. Eye-rim vermilion. Legs and feet 

 red. In winter, there is no black collar, and top of head is 

 greyish. Wing 260-266. Tarsus 30-32. Bill 18-19 (H.). Young: 

 white ; spot behind ear, shoulders, inner wing coverts, tips of 

 primaries .and end of tail brown ; legs and feet brown. 



Breeds. — Only known locality so far is in N. Siberia (Kolyma 

 Delta). Has occurred all over Arctic regions ; is a rare winter 

 visitor to Europe, recorded Faroes, Heligoland, \'orkshire, France 

 and Sardinia. 



