174 
ANAS HYPERBOREA. 
255 . ANAS HYPERBOREA . — YOUNG OF THE SNOW GOOSE. 
WILSON, PLATE LXIX. FIG. V. 
The full plumaged perfect male bird of tliis species 
has already been described in the preceding article, 
and I now hazard a conjecture, founded on the best 
examination I could make of the young bird, comparing 
it with the descriptions of the different accounts, that 
the whole of them have been taken from the various 
individuals of the present, in a greater or lesser degree 
of approach to its true and perfect colours, &c. 
These birds pass along our coasts, and settle in our 
rivers, every autumn ; among thirty or forty, there are 
seldom more than six or eight pure white, or old birds. 
The rest vary so much, that no two are exactly alike ; 
yet all bear the most evident marks, in the particular 
structure of their bills, &c. of being the same identical 
species. A gradual change so great, as from a bird of 
this colour to one of pure white, must necessarily 
produce a number of varieties, or differences in the 
appearance of the plumage, but the form of the bill and 
legs remains the same, and any peculiarity in either is 
the surest mean we have to detect a species under all 
its various appearances. It is therefore to be regretted, 
that authors have paid so little attention to the singular 
conformation of the bill ; for neither that nor the internal 
peculiarities are at all mentioned. 
The length of the bird was twenty-eight inches; 
extent, four feet eight inches ; bill, gibbous at the sides 
both above and below, exposing the teeth of the upper 
and lower mandibles, and furnished with a nail at the 
tip on both ; the whole being of a light reddish purple, 
or pale lake, except the gibbosity, which is black, and 
the two nails, which are of a pale light blue ; nostril, 
pervious, an oblong slit, placed nearly in the middle 
of the upper mandible ; irides, dark brown ; whole 
head, and half of the neck, white ; rest of the neck 
