ANATIDiE, SWANS. GEN. 247. 



281 



247. Genua CYGNUS Linnseus. 



*^.* Adult plumage entirely white ; younger, the head and neck washed with 

 rusty brown ; still younger, gray or ashy. Bill and feet black. Length 4-5 feet. 

 UyC Trumpeter Swan. Tail (normally) of 24 feathers. No yellow spot on 

 bill, which is rather longer than the head, the nostrils fairly in its basal half. 

 Mississippi Valley, westward and northward; Canada (O. passmorei 

 HiNCKs). Sw. and Eioh., Fn. Bor.-Am. ii, 464; Nutt., ii, 370; Aud., 

 vi, 219, pis. 382, 383; Bd., 758 buccinator. 



Fig. 182. Auicricau Swau. 



/y' 7 7 Whistling Swan. Tail (normally) of 20 feathers. A yellow spot on bill, 

 which is not longer than the head ; nostrils median. N. Am. G. hewichii 

 Sw., Fn. Bor.-Am., 465; C./erus Nutt., ii, 366; O. beivickii Nutt., ii, 

 372; C amencawMS Aud., vi, 226, pi. 384; Bd., 758. . . americanus. 



Suhfamily ANSEBINyU. Geese. 



Lores completely feathered ; tarsi entirely reticulate. Neck in length between 

 that of swans and of ducks ; cervical vertebrae about 16 ; body elevated and not so 

 much flattened as in the ducks ; legs relatively longer ; tarsus generally exceeding, 

 or at least not shorter than, the middle toe ; bill generally rather short, high and 

 compressed at base, and tapering to tip, which is less widened and flattened than is 

 usual among ducks, and almost wholly occupied by the broad nail. The species 

 as a rule are more terrestrial, and walk better, than ducks ; they are generally 

 herbivorous, although several maritime species (gen. 249, and an allied South 

 American group) are animal-feeders, and their flesh is rank. Both sexes attend to 

 the young. A notable trait, shared by the swans, is their mode of resenting 

 intrusion by hissing with outstretched neck, and striking with the wings. With 

 some exceptions the plumage is not so bright and variegated as that of ducks, and 

 the speculum is wanting ; there is only an annual moult, and no seasonal change of 

 plumage ; the sexes are generally alike. Most of the geese fall in or very near 

 gen. 248 and 250, and are modelled in the likeness of the domestic breeds. The 

 more notable exotic forms are : — the Australian Anseranas melanoleuca and 

 Cereopsis novai-hollandice, the former having the feet little more than semipalmate, 

 the latter scarcely aquatic, with very long legs, much bare above the suffrago, and the 

 bill small, very membranous ; the African Plectropterus gambensis, a purplish-black 



KEY TO N. A. BIRDS. 36 



