AMERICAN SWAN. 145 



Science and Arts, Vol. XXII., first distinguished this species from the 

 others with which it had been confounded, having obtained good dis- 

 tinctive characters from the peculiar curve of the trachea, and other 

 internal and external circumstances. A mature individual which he de- 

 scribes weighed 21 lb. Its principal dimensions were : — Length to end 

 of tail 54 inches ; extent of wings 86 ; wing from carpus 23 ; middle 

 toe 6 ; intestine 127. The tail-feathers were 20. He then continues : 

 " The youngest and smallest specimen I have met with, had a very 

 soft, reddish-white bill, with a brown point, and measured three inches 

 from the point of the beak to the forehead ; six inches and one-eighth 

 to the occiput, and the usual position of the coloured spot was covered 

 to one inch and three-eighths in front of the eye, with small orange- 

 yellow feathers, which extended down to the gape. The plumage, to 

 the end of the tail and primaries, was of a deep leaden tint, and the legs 

 were of a light grey colour. This specimen measured six feet and 

 eight inches between the points of the extended wings ; four feet two 

 inches from the point of the beak to the tail, and weighed eleven 

 pounds. In the specimen above, the yellow spot on the bill was five- 

 eighths of an inch in length, starting at the front corner of the eye, and 

 running towards the nostrils, and one-fourth of an inch in breadth. In 

 twenty specimens I have now examined of the American Swan, I have 

 never seen this spot more than one inch in length, and half an inch in 

 breadth, and in many of them an oblong mark of the size and shape of 

 a little finger nail was alone found. In one specimen, which weighed 

 sixteen pounds, this spot was but one-fomlh of an inch square, and did 

 not quite reach the eye. As the colour and extent of this spot are as- 

 smned by Mr Yareell as one of the principal external specific diffe- 

 rences between his two English Swans, I have taken particular care to 

 ascertain, beyond a doubt, the tint in the American bird, and I find 

 that it ranges from a pure gamboge-yellow to a bright red orange, and 

 without any regard to sex or age, except in the yearling, as above men- 

 tioned, when it is covered by small feathers. This mark is always in 

 the same position. The feathers continue, except at the anterior fourth 

 where the yellow spot reaches them, to the very edge of the eyelids 

 which are yellow. In every case, the bill has been one-eighth of an 

 inch narrower at the middle than near the point, and in all young birds 

 where the plumage had become white, a dirty-yellow tinge around the 

 head and back of the neck, marked its immaturity. 



VOL. V. V 



