136 ANSERIFORMES CHAP. 
and black beak, except in C. olor, where it is plumbeous. In 
habits Swans are much alike, though the notes differ somewhat, 
and the Mute Swan merely hisses or croaks in captivity; the 
latter and the Black Swan are noted for the graceful curve of 
the neck and their greenish eggs; while the wing-feathers and 
scapulars are habitually puffed out when on the water. Swans 
were “ Royal Birds” in mediaeval England, and a licence was 
necessary to keep them, but for this subject and that of the “ Swan- 
marks” on the bill, as well as for accounts of decoys, hybrids, and 
Fic. 86. Bewick’s Swan. Cygnus bewicki. x +4 
domestic races in the Family, the reader must be referred to the 
works of Professor Newton,’ Count Salvadori,” and other authors. » 
Fossil remains of this group are found throughout the Miocene 
of France, Switzerland, Germany, and Italy, referred to Anser and 
Anas, with Chenornis graculoides ; the Pliocene of Oregon has 
furnished Branta, Cygnus, and Anser, that of Italy Anas and 
Fuligula ; the Plistocene of Malta Cygnus and Palaeocyenus, that 
of Brazil Chenalopex. The superficial deposits of New Zealand con- 
tain Cnemiornis, mentioned above, as well as Chenopis and Biziura ; 
the Queensland drifts the last-named, and, it is said, Anas, 
Dendrocycna, and Nyroca; the Mare aux Songes of Mauritius 
Anas and Sarcidiornis. Centrornis majori is a remarkable form 
1 Cf. Dict. Birds, artt. Duck, Goose, Swan, and the references there given. 
2 Cat. Birds Brit. Mus. xxvii. 1895. 
