ANATIDAE 1 1 I 



politan Family Anatidae, with the Swans, Geese, and Ducks : 

 where, in spite of many attempts at sul)division, the lines of 

 demarcation cannot yet be finally determined. Count Sahaduri, 

 however, having lately propounded a carefully-elaborated arrange- 

 ment,^ I have adopted his Sub-families in the present volume, 

 viz. (1) Merginae, (2) Merganettinae, (3) Erismaturinae, (4) 

 Fuligulinae, (5) Anatinae, (6) Chenonettinae, (7) Anserlnae, (8) 

 CereoiJsinae, (9) Flectropterinae, (10) Anser anatinae, and (11) 

 Cygninae. 



The skull is short and robust ; while the neck is abnormally 

 developed, with extra vertebrae, in the Swans, and is usually 

 long, though less so in the Sea-Ducks ; in the Merginae and 

 some Fuligulinae the customary posterior notches in the sternum 

 are converted into two complete fenestrae or apertures. The 

 l)ill is almost entirely covered witli a soft sensitive membrane, 

 ending in a borny process termed the nail, the skin being warty 

 in Anse I'd lias and Clien rossi ; Cereo2)sis has a large tumid cere; 

 both sexes of Cygnus melanocory^^hus and C. olor have a knob 

 at the base of the culnien, as have the males of Plectro'pterus, 

 Tadorna cornuta, and the domesticated form of Cycnopsis 

 cycno'ides ; the same sex oi Soniateria spectahilis has the posterior 

 portion of the maxilla spread into a disk ; Oedcniia, has it con- 

 siderably swollen even in the female ; Cairina and Flectropterus 

 have caruncles on the forehead ; Save id ior wis has a Heshy comb 

 at the proximal extremity of the beak in the male ; while Biziura 

 has a dependent flap on the chin, and a small suljgidar pouch. 

 The bill is usually broad and depressed, and may be sulj-conical, 

 as in many (reese ; spatulate, as in Spatula and MalacorliyncJius; 

 or somewhat less dilated, as in Chaulelasmus, and so forth. There 

 is a distinct hook at the tip in Mergus, Dendrocycna, and Acx ; 

 the culnien is concave in 3Iarniaronetta and Stictonetta ; the nail 

 is l)eut inwards in the latter and Frismatura, while the maxilla 

 may overlap the mandible, or the covering membrane may even 

 hang over the latter, as in JIalarorhy)ichus, Hyvienolaemus, and to 

 a less extent in F/asm<inetta and Nesonetta. The length is very vari- 

 able, but the thin elongated " sawbill " of Mergus, with its serrated 

 edges, is especially remarkable. j\Iost characteristic of the Family 

 is the presence of highly-developed lamellae or transverse tooth-like 

 processes on both maxilla and mandible, which are visible when 

 1 Cat. Birds Brit. Mu^. xxvii. 189.'^, yy. 23, 24. 



