46 



KEY TO THE BIRDS OF EASTERN NORTH AMERICA. 



FAMILY DIOMEDEID^E. 



Albatrosses. 



Very large wing, over 19 inches long; upper mandible, curved near 

 tip, forming a hook, the end (unguis) enlarged ; nostrils, separate and 

 tubular; hind toe, rudimentary, often apparently wanting. 



* Group 1. Wing, 17 to 21 inches long 



Bill, dark; the top (culmen), yellow. A very large 

 sea bird. 



Thalassoyeron ciihninatits. Yellow = nosed Albatross. 



See No. 56. 



FAMILY PROCELLARIID^E. 

 Shearwaters, Petrels, and Fulmars. 



Nostrils, tubular, united in one double=barrelled tube; front toes, pal-= 

 mate (full webbed) ; hind toe, very small, and in some cases entirely 

 absent; upper mandible, curved near tip; wing, less than 19 inches long. 



* Group 1. Wing, less than 5.50 inches long. 



General plumage, sooty black, the underparts with faint 

 brownish tinge ; upper tail coverts, white, some of them tipped 

 with black. Procellaria pelagica. Stormy Petrel. 



See Xo. 67. 



67 



* Group 2. Wing, 5.50 to 6.50 inches long. 



Tail, nearly square; upper tail coverts, white, not tipped with black; underparts, dull 

 black; tarsus, over 1.05. Oceanites oceanicus. Wilson's Petrel. 



See No. 69. 



Tail, decidedly forked; upper tail coverts, white, not tipped with black; underparts, 

 brownish black or sooty brown; tarsus, less than 1.05. 



Oceanodroma leucorhoa. Leach's Petrel. 



See No. 68. 



Underparts, white. Pelagodroma marina. White=faced Petrel. 



See No. 71. 



* For directions for measurement, see page 9. 



