Swan. NATATORES. CYGNUS. 285 
YARRELL in a paper published in the sixteenth volume of 
the Linnean Transactions; and also in another, contained in 
the first volume of the Transactions of the Natural History 
Society of Northumberland, Durham, and Newcastle, to 
which I beg to refer my readers. In external appearance 
the present bird bears avery close resemblance to the Whis- 
tling Swan, and might, upon a cursory view, be easily mis- 
taken for a small variety of it, as must have frequently hap- 
pened previous to the observations made by Mr Wrneare ; 
for the detection of several specimens that have remained for 
many years in private collections, under the above designa- 
tion, shew that the species is not a new arrival, but may 
have been in the habit of visiting this country, in connexion 
with the former, for an indefinite period, although not in 
such numbers as its companion. The peculiarity of the in- 
ternal structure had previously attracted some notice ; for 
Monrtacu, in the Supplement to his Ornithological Diction- 
ary, under the article Whistling Swan, gives an accurate de- 
scription of the trachea and sternum of a bird of this new 
species ; and which, from having been observed in a male 
specimen, he, without extending his examination, or noticing 
its other peculiar features, supposed indicative of, and con- 
fined to, the male of the species then under his consideration. 
The external characters distinctive of the new species, are, in 
the first place, being about one-third less than the usual size 
of the preceding (the average length of Cyg. Bewickit being 
three feet ten inches, and the breadth six feet ; whilst that of 
C. ferus is five feet, and the breadth upwards of eight) ; se- 
condly, in the colour and form of the bill, which differs at its 
base from that of the Whistling Swan, and, in old birds, has 
at the junction of the upper mandible with the cranium a 
considerable tubercle or knob; and, thirdly, in the number 
of the tail-feathers, the present species having only eighteen 
and the other twenty. The wings are also shorter, and do 
not cover so large a portion of the tail; the legs are of a 
deeper black, and the neck, besides being comparatively 
