1 8 CHECK-LIST OF NORTH AMERICAN BIRDS. 



47. Larus marinus Linn. 



Great Black-backed GiuU. 



Larus marinus Linn. S. N. ed. lo, L 1758, 136. 



[B 660, C 546, R 663, C 77 I.J 



Geog. Dist. — Coasts of the North Atlantic ; south in winter to 

 Long Island and Italy. 



48. Larus schistisagus Stejn. 



Slaty-backed GuU. 



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 GuU. 



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



[B 662, C 5473, R 664, C 774.] 



, Geog. Dist. — Pacific coast of North America, breeding from 

 Lower California northward to British Columbia. 



[50.] Larus afEinis Reinh. 



Siberian Gull. 



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



[B— , C— R66s, C776.] 



Geog. Dist. — Northern Asia and Europe, southward in winter to 

 northern Africa. Accidental in Greenland. 



51. Larus argentatus Brunm. 



Herring GuU. 



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



[B— , C 547, R 666, C 772.] 



Geog. Dist. — Old World, south to the Azores; Cumberland 

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



