OP THE BEITISH ISLANDS. 303 



Family ANATID/E. The Swans, Geese, Ducks, 

 and Mergansers. 



The birds comprising this by far the largest division of the order may be 

 distinguished by their peculiar laminated bill, short legs, and webbed feet. They 

 are characterised by having the basipterygoid processes placed as far forward as 

 possible and by the metatarsus being about equal in length to the fermur, 

 reticulated behind and generally in front. Their sternum contains one notch 

 only on each side of the posterior margin. The tongue is large and fleshy, the 

 edges serrated. The bill is generally broad and flat, and has a nail at the tip of 

 the upper mandible. Count Salvadori (whose arrangement as elaborated in the 

 Catalogue of Birds in the National Collection we propose chiefly to follow) divides 

 the present family into eleven fairly well-defined subfamilies, five of which are 

 represented in our area. 



Subfamily CYQN1N/E, or Swans. 



The birds included in the present subfamily are distinguished from their allies 

 by having the lores (space between the eye and the bill) bare of feathers. Their 

 reticulated metatarsus further distinguishes them from the Ducks, whilst the 

 shortness of that member (not so long as the middle toe) is a point of distinction 

 from the Geese. The hind toe is not lobed ; the neck is extremely long. The 

 sexes are nearly alike in colour. One moult in autumn. 



This subfamily is composed of seven species, referable to three genera. 



