AMERICAN SWAN. 687 



in every respect, with the exception of its having more buffy 

 or rufous feathers ; and the bills of the two showed not the 

 slightest difference in form, measurements, or lamellae. In 

 fact, so perfect an agreement could not take place in two 

 different species. The wings also agreed as to the number 

 and form of the quills — which, however, were smaller — with 

 those of an adult Cygnus Americanus, and the tail was pre- 

 cisely similar to that of a young bird in my collection, only 

 that the one had eighteen the other twenty feathers. The 

 tarsi and toes were exactly similar ; the scutella the same in 

 number and form ; but the claws of my young bird were 

 shorter and paler than those of the adult. As to the tail- 

 feathers, M. Temminck, Mr. Blythe, and others, have found 

 them to vary as to number in Swans generally, and Mr. 

 Thompson and others have shown that even of Cygnus 

 Bewickii, the normal number is not eighteen but twenty. 

 If it, then, should frequently have eighteen, there is no 

 reason to suppose that Cygnus Americanus may not also 

 sometimes have two less than usual. 



On the whole, then, the result of my examination is, 

 that the individual in question is shewn by the structure 

 and curve of its trachea to be similar to Cygnus Americanus 

 and Cygnus Bewickii ; that, although a young bird, it 

 greatly exceeds the adult of the latter species in all its 

 dimensions, and especially in those of its digestive and respi- 

 ratory organs ; and that it agrees in all essential respects 

 with the former species, its identity being especially estab- 

 lished by the perfect agreement of the bill and head with 

 those of a young bird of that species ; finally, that if not 

 Cygnus Americanus, it is a species not hitherto described, 

 differing from it only in having eighteen instead of twenty 

 tail-feathers. But as the variation of the tail-feathers in 

 Swans is notorious, this circumstance appears to be of no 

 importance whatever. 



The proventriculus of this individual contained some 

 fleshy roots and rhizomata, with quartz sand. In the ante- 

 rior half of the intestine was a great number, forty or fifty, 

 slender tape-worms. Probably the examination of these 

 animals might be of importance, as each species of Swan 



