37 
pursue their agile prey with an astonishing 
swiftness underwater; although bad run- 
ners, they walk better than the Mergansers, 
but more upright ; their long tail furnished 
with strong elastic feathers, serves them 
for a support in walking. Their food con- 
sists of fish, particularly eels ; they often 
swim with their head only above water ; 
their flight is swift and continued. 
They more frequently perch upon trees 
than the Pelicans: their nests, which 
they place according to circumstances on 
the earth, in the holes of rocks, or upon 
trees, are composed of rushes, grass, or 
sea-weed rudely put together. 
There is partly a double moulting in all 
the known species ; that of the spring pro- 
duces long white feathers on the neck 
and thighs* which, as well as their crest 
feathers, drop off before the autumnal 
moulting; the young of the first year dif- 
fer much from the adults ; but there is no 
difference between the sexes ; the plumage 
of the young has always been taken for 
that of the female. 
