72 AVES. 



less depressed ; the tip rounded and obtuse, fur- 

 nished with a nail: wings moderate: legs placed 

 in or near the equilibrium : feet four-toed., pal- 

 mated ; hind toe free, placed high on the tarsus. 



* (ANSERINE.) 



87- ANSER Bill as long as, or shorter than the 



head, higher than broad at the base, subconic; the upper 

 mandible deflected at the tip ; the lower one flat and 

 straight, narrower : nostrils a little behind the middle : neck 

 of moderate length ; wings tuberculated, or spurred : legs 

 in the equilibrium : tarsi slightly elongated. 



(1. ANSER.) Bill as long as the head; the tips of the lamellae 

 exserted, appearing like sharp teeth. 



(2. BERNICLA.) Bill shorter than the head, somewhat slender; the 

 edges of the mandihles concealing the tips of the lamellae. 



(3. PLECTROPTERUS.) Bill moderate; furnished with a fleshy 

 tubercle at its base: wings armed with spurs. 



88. CYGNUS Bill moderate, of nearly equal breadth 



throughout, furnished at its base with a knob or fleshy 

 tumour, convex above; the upper mandible deflected at 

 the tip ; the lower one flat : nostrils medial : neck very 

 long : legs a little beyond the equilibrium : tarsi short. 



** (ANATINvE.) Hind toe simple: tarsi somewhat 



round. 



89. TADORNA Bill shorter than the head, with an 



elevated tubercle at the base, depressed or concave in the 

 middle, of nearly equal breadth throughout ; the upper 

 mandible laterally grooved near the tip, which is slightly 

 recurved : face and lore feathered : nostrils large, oval, 

 a little before the base: tail even. 



* 90. CAIRINA. Bill furnished with an elevated tubercle at the 

 base ; the edges of the mandibles sinuated : face and lore covered with a 

 naked warty skin : nostrils round, basal : wings tuberculated. 



91. ANAS Bill as long as, or rather longer than the 



head, simple at the base, broad and depressed generally 

 throughout its whole length, sometimes widening ante- 



