CHAPTER REV: 
Mergansers. 
The three species which compose this sub-family are 
at once to be distinguished, as above stated, by the form 
of the beak, which in all is markedly narrow, shallow, 
and tapering, being more than twice as broad at the 
root as at the tip. Its edges are armed with teeth, of 
which the upper row are plainly visible even when the 
bill is closed, and the large nail takes up the whole of 
the tip and forms a hook. The nostrils are nearer the 
root than the tip, as in ordinary Ducks. 
It is practically only the peculiar bill which marks 
these birds off at all from the true Ducks (A natine), and 
perhaps they hardly deserve sub-family rank, since, 
except for the form of the beak, they present no note- 
worthy distinction from the Golden-eye, which every- 
body would call a Duck. Still they have nearly always 
been given a separate position, and may retain it in this 
series. 
Mergansers are about the size of or smaller than a 
tame Duck, and in general form, present a fair-sized 
head, a rather short neck, and a somewhat flat body. 
The wings are pointed, and if anything rather short, 
the tail rather long and rounded, and the feet are set far 
astern, with short shanks ; these being much exceeded 
in length by the middle toe, to which the outer toe is 
about equal, giving a large foot. The hind toe is 
furnished on its lower edge with a flap or lobe of skin. 
The plumage of the Mergansers is pied, and very 
different in the two sexes, the males being black*and 
white and the females grey, brown and white. The 
