OTHER SWANS 
black swan, in any case, is a precise contrast to swans in 
general. All the European forms, and those of North 
America, about seven species in all, are white. On the 
other hand, Cygnus atratus of Australia is approached, 
through longo intervallo, by the black-necked swan of 
South America (Cygnus nigricollis), which is white with 
the exception of its black neck. The real black swan is 
not altogether black. Animals that are either white or 
black are seldom perfectly so. Few are so black as 
popular works and general opinion paint them, even 
inhabitants of more torrid climes than Australia. About 
the wings are a few white feathers ; and the rich crimson 
skin about the beak and face is well known. It is note- 
worthy that this redness of visage accompanies the 
darkening of the general hues. The white swans of the 
Old World have for the most part yellow patches of naked 
skin about the face. With the blackening of the feathers 
is a concomitant darkening of this yellow into red. That 
there is nothing really remarkable about the black swan 
of Australia except its blackness, is shown by the fact 
that its cygnets are exactly of the usual ugly duckling 
coloration, a dingy grey. This bird is also in every 
other respect a true swan. A swan isa little difficult to 
define. The swans, ducks, and geese form a highly 
natural assemblage of birds which hardly need charac- 
terization, so plainly can they be identified as such by 
the veriest tyro. Furthermore, every one knows for all 
practical purposes which are swans and which are ducks, ~ 
though to tell geese, not from swans, indeed, but from 
ducks, is not so easy a task. But when we come to 
write down in cold and logical black and white the dis- 
tinctions between a swan and a duck, there is really 
little besides length of neck which can be used. If it 
were not so grave an anachronism, one might suppose 
that the poetical remembrance of the song of the dying 
swan might have come from this Australian bird, which 
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