$228a. 
+#229, 
$229a. 
141 
Halizétus albicilla groenlandicus Brehm, 
Handb. Naturg. Vég. Deutschl., p. 16 
(1831). [Greenland.] 
Greenland White-tailed Eagle. 
Larger ; wing ¢ 615, 9 ad. 720 mm. (juv. 
685-710 mm.) (cf. Hartert, Végel d. 
palaarkt Fauna, p. 1178). 
Halizétus  leucocephalus _leucocephalus 
(Linn.), S.N., ed. xii., 1., p. 124 (1766). [ex 
Catesby—Carolina.] 
Bald Eagle. 
Wing ad. 585-625 mm.; head and neck 
all round, rump, upper tail-coverts and tail 
pure white. Immature: head and neck 
black and tail mingled white and black at 
first. 
Halizétus leucocephalus alascanus C. H. 
Townsend, Proc. Biol. Soc. Wash., xi., p. 
145 (1897). [Unalaska, type in U.S. Nat. 
Mus. ] 
Alaskan Bald Eagle. 
Rather larger; wing g 625-635, 92 600- 
642 mm. 
Greenland. 
Canada and 
United States, 
S. to Lower 
California and 
N. Mexico. 
N.W. Alaska, 
Bering I[., 
N.W. Mackenzie 
and N. Ungava 
S: to “Brit: 
Columbia and 
Great Lakes. 
Gen. LXIV. THALASSOAETUS Kaup (1844). 
Type by monotypy Aguila pelagica Pall. 
Tail strongly graduated, with 14 feathers, instead 
of 12; 
bill larger and more powerful, height 
greater but variable. ~ 
