1 8 CHECK-LIST OF NORTH AMERICAN BIRDS. 



47. Lams marinus LINN. 



Great Black-backed Gull. 



Larus marinus LINN. S. N. ed. 10, I. 1758, 136. 

 [B 660, C 546, R66 3 , C 771.] 



GEOG. DIST. Coasts of the North Atlantic ; south in winter to 

 Long Island and Italy. 



48. Larus schistisagus STEJN. 



Slaty-backed Gull. 



Larus schistisagus STEJN. Auk, I. July, 1884, 231. 

 [B , C R , C .] 



GEOG. DIST. North Pacific, chiefly on the Asiatic side ; Herald 

 Island, Arctic Ocean, and Alaskan coast of Bering Sea. 



49. Larus occidentalis AUD. 



Western Gull. 



Larus occidentalis AUD. Orn. Biog. V. 1839, 320. 



[B 662, C 547^, R 664, C 774.] 



GEOG. DIST. Pacific coast of North America, breeding from 

 Lower California northward to British Columbia. 



[50.] Larus affinis REINH. 



Siberian Gull. 



Larus affinis REINH. Vid. Med. 1853, 78. 



[B C , R 665, C 776.] 



GEOG. DIST. Northern Asia and Europe, southward in winter to 

 northern Africa. Accidental in Greenland. 



51. Larus argentatus BRUNN. 



Herring Gull. 



Larus argentatus BRUNN. Orn. Bor. 1764, 44. 

 [B- C 54 7, R666, C772-] 



GEOG. DIST. Old World, south to the Azores ; Cumberland 

 Sound ; occasional on the eastern coast of the United States. 



