FAM. LX. TERNS AND GULLS 



329 



E. Primaries peari-gray, tipped with white but having distinct gray 



spaces on the outer webs 17. Kumlien's Gull. 



E. Primaries with white tips and dusky or bhvck spaces near tips (in 

 young sometimes all dark). (F. ) 

 F. Shafts of tlie primaries white tlirough the dark spaces in adult ; wing, 



17-20 long ; back dark slaty -black 18. Great Black-backed Gull. 



F. Shafts dark like the spaces. (G. ) 



G. Wing, 15| or more long 19. Herring Gull. 



G. Wing le.ss than 15f long 20. Ring-billed Gull. 



H. Wing over 16 J long ; culmen over 2 1-3. Glaucous Gull. 



H. Wing under 16^ long ; culmen under 2 10. Iceland Gull. 



13. Ivory Gull (39. 

 pure white gull with 

 black feet and yel- 

 low bill. The yoiuifj 

 has some gray patches 

 on different parts of 

 the body, but espe- 

 cially at the tips of 

 the tail feathers and 

 primaries; sometimes 

 the wing coverts have 

 black spots at their 

 tips. 



Length, 15-20 ; wing, 

 lHi;tan, 5 



Gcii'ia diba). — A large, rare, northern, 



tarsus, IJ ; culmen, If. Arctic regions ; sinUh in the Atlan- 

 tic to about the border of the United States. 



34. Kittiwake (40. 7^/.^^ triddctf/Ia). — A three- 

 toed, white gidl, with pearl-gray mantle, black 

 tips to the outer primaries, yellowish bill, 

 and black feet. The hind toe is rep- 

 resented by a little knob. The 

 third to the fifth primary 

 have white tips be- 

 yond the black. In 

 Avinter the top of the 

 head and the back of 



Kittiwake 



the neck are tinged 



