10 BULLETIN 126, UNITED STATES NATIONAL MUSEUM. 



face for a considerable distance; when flying off an island it often 

 does the same thing unless it gets a good start from some high place, 

 so that it can swooj) downward. In swift water it has to rise down- 

 stream, as it can make no headway against the current; but it gen- 

 erally prefers to fly upstream if it can. Mr. Aretas A. Saunders writes 

 to me, in regard to the flight of mated pairs, noted in Montana, 

 "that they flew oft', with the male in the lead in each case," also 

 "that they left the water flying in a long, low slant upstream, not 

 rising high enough to see them above the willows that lined the stream 

 until they had flown a considerable distance." When well under 

 way the flight of this species is strong, swift, and direct; on its breed- 

 ing grounds it usually flies low, along the courses of rivers or about 

 the shores of lakes, seldom rising above the tree tops; but on its 

 migrations it flies in small flocks, high in the air with great velocity. 

 The drake may be easily recognized in flight by its large size, loon- 

 like shape, its black and white appearance above, dark green head 

 and white underparts; its flight is said to resemble that of the mallard. 

 The female closely resembles the female red-breasted merganser, but 

 it is a more heavily built bird, has a more continuous white patch in 

 the wings, the white tips of the greater coverts overlapping the black 

 bases of the secondaries, giving the appearance of a large v/hite spec- 

 ulum, whereas in the red-breasted merganser the black bases of the 

 secondaries show below the greater coverts, forming a black stripe 

 through the middle of the white speculum. When flying to its nest 

 cavity in a tree or cliff it rises in a long upward curve and enters the 

 hole with speed and precision. Mr. Harry S. Swarth (1911) refers to— 



a peculiar habit which made this species quite conspicuous throughout the summer, 

 was that of individuals rising high in the air and circling about for hours at a time, 

 uttering at frequent and regular intervals a most uumelodious squawk. Both sexes 

 were observed doing this, and the habit was kept up until about the end of August. 



This sheldrake is probably the most expert diver of its tribe, being 

 built somewhat like a loon and approaching it in aquatic ability. It 

 can sink quietly down into the water like a grebe or dive quickly 

 with a forward curving plunge, clearing the water for a foot or more, 

 as it does so. It swims swiftly on the surface, but can attain even 

 higher speed below it, where few fish can escape it. Dr. Charles W. 

 Townsend (1909) infers from its method of diving, that the wings are 

 not used when swimming under water and he quotes a statement 

 from Selous to the same effect; he says: 



The American and the red-breasted merganser both dive like the cormorant. They 

 often leap clear of the water, in graceful curves, with their wings cleaving closely to 

 the sides. At other times the leap is much curtailed, or they sink beneath the surface 

 without apparent effort. I should infer, therefore, that the wings were not used 

 under water. 



