334 WHITE-HEADED EAGLE. 



twelfths long, while the other measures 1 inch 10 twelfths. The heart 

 is conical 1^ inch in length, 1^ inch in its greatest breadth. 



The trachea, j kl,is7 inches long, flattened, 4i twelfths in breadth 

 at the upper part, enlarging to 5 twelfths, but towards the end only 3^ 

 twelfths and round. The number of its rings is 106 ; they are firm and 

 well ossified ; the last half ring, /, broad, being 5 twelfths in extent, as is 

 the first half ring of the bronchi, with a large membrane interposed. 

 The lateral or contractor muscles k, are strong ; the sterno-tracheal, m, 

 very large ; and there is a pair of inferior laryngeal muscles inserted 

 upon the bronchial membranes o. 



WHITE-HEADED EAGLE. 



Falco leucocephalus, Linn. 



PLATE XXXI. Vol. I. p. 160. Adult. 

 PLATE CXXVI. Vol. II. p. 160. Young. 



From what I have already said of this species it will be understood 

 that it is to be met with more abundantly than elsewhere, in the space 

 bounded by the Mississippi and the Atlantic coast of our Middle States, 

 it being more numerous, however, in the Southern States. It appears 

 from what is said of it in the Fauna Boreali- Americana, that it has not 

 been met with farther north than Great Bear Lake, or latitude 62° N.; 

 but Dr TowNSEND met with it on the Columbia River and in California. 

 M. Temminck must be mistaken, I should think, in assigning to it the 

 regions within the Arctic Circle, as its habitual residence. I have not 

 been able to see a single specimen that could be proved to have been 

 procured in Europe. 



Adult Male. 



Bill about a third shorter than the head, very deep, compressed. 

 Upper mandible with the dorsal outline nearly straight as far as the 

 edge of the cere, then decurved in the third of a circle^ the ridge broad 

 and a little convex on the cere, then narrowed, but again enlarging, 

 and towards the end narrowed, but in its whole length convex, the 

 sides sloping and flat at the base, sloping and considerably convex to- 



