116 NORTH AMERICAN OOLOGY. PART I. 



opposite shores of Asia, and the Japan Islands. Of its habits little is positively 

 known, and the notices by Pallas, the Russian naturalist, are the only reliable ones 

 that have been published. The account of the eggs quoted above is quite indefinite, 

 and probably not exactly correct. The eggs of Swans, for the most part, are not 

 Avhite, and of a more elliptical shape than those of the Raptorial fomily. 



Hali^tus leucocephalus. — In a recent paper by Mr. Cassin, published in the 

 "United States Magazine," New York, while speaking of the doubts existing among 

 naturalists as to the reality of the Bird of Washington [Halicetiis washingtonii), he 

 mentions that, in his opinion, " there are two species of White-headed Eagles inhabit- 

 ing the States on the Atlantic sea-board. They appear to be constantly different in 

 size, and we are not without suspicion that one is the Northern and the other a 

 Southern bird. The larger has the bill much shorter, and very much as represented 

 in Mr. Audubon's plate of the Washington Eagle ; and, in fact, is in all respects 

 that bird, except that it has not the large scales in front of the tarsus continued 

 without interruption to the toes, as represented in the plate to which we allude." 

 If Mr. Cassin's conjectures should prove to be well founded, the egg represented in 

 the plate may belong to the more southern species. I am informed by Dr. Heer- 

 mann that it was obtained in Maryland, and not in California, as stated (page 52). 

 It is marked on the shell, February, 1856. 



HalitEtus grcenlandicus. — In the jireceding pages, the Haliatus albidlla, or 

 Sea-Eagle of Europe, is given as a bird of Greenland, and therefore entitled to a 

 place among North American species. Its claims to be so regarded Avould seem to 

 be somewhat problematical, inasmuch as it is now stated by Mr. Cassin that there 

 is a Sea-Eagle in Greenland not identical with the European variety. It is also 

 distinct from the White-headed Eagle, which it closely resembles. It therefore 

 remains to be ascertained whether the H. aJhidUa is entitled to a place in the North 

 American Fauna, or whether the Greenland bird, H. gra'tilandims, is the sole occu- 

 pant of that region. 



